Commit graph

2050 commits

Author SHA1 Message Date
Paolo Bonzini 27ebc27beb
target-m68k: make cpu-qom.h not target specific
Make M68KCPU an opaque type within cpu-qom.h, and move all definitions of
private methods, as well as all type definitions that require knowledge
of the layout to cpu.h. This helps making files independent of NEED_CPU_H
if they only need to pass around CPU pointers.

Backports commit a836b8fa00fa1032ccd234a71b33943627d211ea from qemu
2018-02-24 00:56:58 -05:00
Paolo Bonzini 2f4ae94b5c
target-i386: make cpu-qom.h not target specific
Make X86CPU an opaque type within cpu-qom.h, and move all definitions of
private methods, as well as all type definitions that require knowledge
of the layout to cpu.h. This helps making files independent of NEED_CPU_H
if they only need to pass around CPU pointers.

Backports commit 4da6f8d954429c0cd1471d25cb9dbe909607374e from qemu
2018-02-24 00:55:22 -05:00
Lioncash 791413630e
target-arm: make cpu-qom.h not target specific
Make ARMCPU an opaque type within cpu-qom.h, and move all definitions of
private methods, as well as all type definitions that require knowledge
of the layout to cpu.h. This helps making files independent of NEED_CPU_H
if they only need to pass around CPU pointers.

Backports commit 74e755647c1598a6845df1ee4f8b96d01afd96e7 from qemu
2018-02-24 00:48:59 -05:00
Paolo Bonzini fee6dcb22a
include: move CPU-related definitions out of qemu-common.h
Backports commit 4b4629d9d26fd0e100d9be526367a96aa35b541d from qemu
2018-02-24 00:33:49 -05:00
Wei Jiangang 7cf135457a
accel: make configure_accelerator return void
Return the negated value of accel_initialised is meaningless,
and the caller vl doesn't check it.

Backports commit bdc3f61dec2f9c227235bb5f677a0272e1184c82 from qemu
2018-02-24 00:31:28 -05:00
Sergey Fedorov eab60b7c77
cpu-exec: Clean up 'interrupt_request' reloading in cpu_handle_interrupt()
Backports commit 8b1fe3f439eaa2f0a6ee7737942bb6c405725867 from qemu
2018-02-24 00:27:05 -05:00
Sergey Fedorov b4b7b88f69
cpu-exec: Remove unused 'x86_cpu' and 'env' from cpu_exec()
Backports commit ba048a4ae15ba0f70c6dcb12ee05db120408de78 from qemu
2018-02-24 00:16:40 -05:00
Sergey Fedorov aefb8935a9
cpu-exec: Move TB execution stuff out of cpu_exec()
Simplify cpu_exec() by extracting TB execution code outside of
cpu_exec() into a new static inline function cpu_loop_exec_tb().

Backports commit 928de9ee14b0b63ee9f9275732ed3e1c8b5f4790 from qemu
2018-02-24 00:15:24 -05:00
Sergey Fedorov d4ef96abf2
cpu-exec: Move interrupt handling out of cpu_exec()
Simplify cpu_exec() by extracting interrupt handling code outside of
cpu_exec() into a new static inline function cpu_handle_interrupt().

Backports commit c385e6e49763c6dd5dbbd90fadde95d986f8bd38 from qemu
2018-02-24 00:09:06 -05:00
Sergey Fedorov c1b52a4387
cpu-exec: Move exception handling out of cpu_exec()
Simplify cpu_exec() by extracting exception handling code out of
cpu_exec() into a new static inline function cpu_handle_exception().
Also make cpu_handle_debug_exception() inline as it is used only once.

Backports commit ea284766ec6b9f1712369249566b4c372f3cec8b from qemu
2018-02-24 00:03:37 -05:00
Sergey Fedorov fc3d135dac
cpu-exec: Move halt handling out of cpu_exec()
Simplify cpu_exec() by extracting CPU halt state handling code out of
cpu_exec() into a new static inline function cpu_handle_halt().

Backports commit 8b2d34e997371c9729a0f41e3cc624d4300bbe78 from qemu
2018-02-23 23:53:20 -05:00
Lioncash 88d00a75ca
cpu-exec: move cpu_exec to the bottom of the file
Remove forward declarations
2018-02-23 23:50:28 -05:00
Sergey Fedorov 0088ca994f
cpu-exec: Remove relic orphaned comment
This comment should have been deleted by commit 0ac087f1f3ae ("removed
unused code") but somehow it is still here. There's no point to keep it.

Backports commit c6f0d9f84c43ae973270df1a77482466558ee487 from qemu
2018-02-23 23:47:05 -05:00
Sergey Fedorov 1a768018c2
tcg: Remove needless CPUState::current_tb
This field was used for telling cpu_interrupt() to unlink a chain of TBs
being executed when it worked that way. Now, cpu_interrupt() don't do
this anymore. So we don't need this field anymore.

Backports commit 3213525f8ab48742db09dab18cb9ae6f36a6c921 from qemu
2018-02-23 23:45:42 -05:00
Sergey Fedorov 73c75b4cf7
cpu-exec: Move TB chaining into tb_find_fast()
Move tb_add_jump() call and surrounding code from cpu_exec() into
tb_find_fast(). That simplifies cpu_exec() a little by hiding the direct
chaining optimization details into tb_find_fast(). It also allows to
move tb_lock()/tb_unlock() pair into tb_find_fast(), putting it closer
to tb_find_slow() which also manipulates the lock.

Backports commit a0522c7a55cc8ac76d82884cf8e52f76daa664cc from qemu
2018-02-23 23:38:57 -05:00
Sergey Fedorov ba9a237586
tcg: Rework tb_invalidated_flag
'tb_invalidated_flag' was meant to catch two events:
* some TB has been invalidated by tb_phys_invalidate();
* the whole translation buffer has been flushed by tb_flush().

Then it was checked:
* in cpu_exec() to ensure that the last executed TB can be safely
linked to directly call the next one;
* in cpu_exec_nocache() to decide if the original TB should be provided
for further possible invalidation along with the temporarily
generated TB.

It is always safe to patch an invalidated TB since it is not going to be
used anyway. It is also safe to call tb_phys_invalidate() for an already
invalidated TB. Thus, setting this flag in tb_phys_invalidate() is
simply unnecessary. Moreover, it can prevent from pretty proper linking
of TBs, if any arbitrary TB has been invalidated. So just don't touch it
in tb_phys_invalidate().

If this flag is only used to catch whether tb_flush() has been called
then rename it to 'tb_flushed'. Declare it as 'bool' and stick to using
only 'true' and 'false' to set its value. Also, instead of setting it in
tb_gen_code(), just after tb_flush() has been called, do it right inside
of tb_flush().

In cpu_exec(), this flag is used to track if tb_flush() has been called
and have made 'next_tb' (a reference to the last executed TB) invalid
for linking it to directly call the next TB. tb_flush() can be called
during the CPU execution loop from tb_gen_code(), during TB execution or
by another thread while 'tb_lock' is released. Catch for translation
buffer flush reliably by resetting this flag once before first TB lookup
and each time we find it set before trying to add a direct jump. Don't
touch in in tb_find_physical().

Each vCPU has its own execution loop in multithreaded mode and thus
should have its own copy of the flag to be able to reset it with its own
'next_tb' and don't affect any other vCPU execution thread. So make this
flag per-vCPU and move it to CPUState.

In cpu_exec_nocache(), we only need to check if tb_flush() has been
called from tb_gen_code() called by cpu_exec_nocache() itself. To do
this reliably, preserve the old value of the flag, reset it before
calling tb_gen_code(), check afterwards, and combine the saved value
back to the flag.

This patch is based on the patch "tcg: move tb_invalidated_flag to
CPUState" from Paolo Bonzini <pbonzini@redhat.com>.

Backports commit 6f789be56d3f38e9214dafcfab3bf9be7191f370 from qemu
2018-02-23 23:34:51 -05:00
Sergey Fedorov c9700af2bd
tcg: Clean up from 'next_tb'
The value returned from tcg_qemu_tb_exec() is the value passed to the
corresponding tcg_gen_exit_tb() at translation time of the last TB
attempted to execute. It is a little confusing to store it in a variable
named 'next_tb'. In fact, it is a combination of 4-byte aligned pointer
and additional information in its two least significant bits. Break it
down right away into two variables named 'last_tb' and 'tb_exit' which
are a pointer to the last TB attempted to execute and the TB exit
reason, correspondingly. This simplifies the code and improves its
readability.

Correct a misleading documentation comment for tcg_qemu_tb_exec() and
fix logging in cpu_tb_exec(). Also rename a misleading 'next_tb' in
another couple of places.

Backports commit 819af24b9c1e95e6576f1cefd32f4d6bf56dfa56 from qemu
2018-02-23 23:29:04 -05:00
Paolo Bonzini 66faf3b5df
tcg: code_bitmap and code_write_count are not used by user-mode emulation
Backports commit 6fad459c91e8a1dedbb6681d3f57ede5222a225c from qemu
2018-02-23 23:17:37 -05:00
Sergey Fedorov ffdc9d6323
tcg: Allow goto_tb to any target PC in user mode
In user mode, there's only a static address translation, TBs are always
invalidated properly and direct jumps are reset when mapping change.
Thus the destination address is always valid for direct jumps and
there's no need to restrict it to the pages the TB resides in.

Backports commit 90aa39a1cc4837360889f0e033ca25cc82100308 from qemu
2018-02-23 23:12:14 -05:00
Sergey Fedorov 73c59faad5
tcg: Clean up direct block chaining safety checks
We don't take care of direct jumps when address mapping changes. Thus we
must be sure to generate direct jumps so that they always keep valid
even if address mapping changes. Luckily, we can only allow to execute a
TB if it was generated from the pages which match with current mapping.

Document tcg_gen_goto_tb() declaration and note the reason for
destination PC limitations.

Some targets with variable length instructions allow TB to straddle a
page boundary. However, we make sure that both of TB pages match the
current address mapping when looking up TBs. So it is safe to do direct
jumps into the both pages. Correct the checks for some of those targets.

Given that, we can safely patch a TB which spans two pages. Remove the
unnecessary check in cpu_exec() and allow such TBs to be patched.

Backports commit 5b053a4a28278bca606eeff7d1c0730df1b047e9 from qemu
2018-02-23 22:26:00 -05:00
Sergey Fedorov 39d262f0d2
tcg: Clean up tb_jmp_unlink()
Unify the code of this function with tb_jmp_remove_from_list(). Making
these functions similar improves their readability. Also this could be a
step towards making this function thread-safe.

Backports commit f9c5b66f487a04d3747dc6997b1503f9258df945 from qemu
2018-02-23 21:40:07 -05:00
Lioncash 68272af618
translate-all: Remove unused variable in size_code_gen_buffer
Also eliminates the unused parameter
2018-02-23 21:38:34 -05:00
Sergey Fedorov c530eb06a9
tcg: Extract removing of jumps to TB from tb_phys_invalidate()
Move the code for removing jumps to a TB out of tb_phys_invalidate() to
a separate static inline function tb_jmp_unlink(). This simplifies
tb_phys_invalidate() and improves code structure.

Backports commit 89bba496322d4cf996d42cdd4bb0912231656c3d from qemu
2018-02-23 21:36:29 -05:00
Sergey Fedorov 0d2e91518b
tcg: Rename tb_jmp_remove() to tb_remove_from_jmp_list()
tb_jmp_remove() was only used to remove the TB from a list of all TBs
jumping to the same TB which is n-th jump destination of the given TB.
Put a comment briefly describing the function behavior and rename it to
better reflect its purpose.

Backports commit 133626783aa5a1bf86332fa3e6f7b8efe005f924 from qemu
2018-02-23 21:34:01 -05:00
Sergey Fedorov d60af028c5
tcg: Clarify thread safety check in tb_add_jump()
The check is to make sure that another thread hasn't already done the
same while we were outside of tb_lock. Mention this in a comment.

Backports commit 9962c478b153a18fe88a6509fe58cd178aff8abc from qemu
2018-02-23 21:32:47 -05:00
Sergey Fedorov e93f68a755
tcg: Init TB's direct jumps before making it visible
Initialize TB's direct jump list data fields and reset the jumps before
tb_link_page() puts it into the physical hash table and the physical
page list. So TB is completely initialized before it becomes visible.

This is pure rearrangement of code to a more suitable place, though it
could be a preparation for relaxing the locking scheme in future.

Backports commit 901bc3deb43bf37c85e43955905d003be7ae5fa5 from qemu
2018-02-23 21:31:36 -05:00
Sergey Fedorov 87f2bb42d4
tcg: Rearrange tb_link_page() to avoid forward declaration
Backports commit e90d96b158665a684ab89b4f002838034b5fafc8 from qemu
2018-02-23 21:28:20 -05:00
Sergey Fedorov fbc0a1105f
tcg: Use uintptr_t type for jmp_list_{next|first} fields of TB
These fields do not contain pure pointers to a TranslationBlock
structure. So uintptr_t is the most appropriate type for them.
Also put some asserts to assure that the two least significant bits of
the pointer are always zero before assigning it to jmp_list_first.

Backports commit c37e6d7e3589ecb96914faa21025ad7ba6654aea from qemu
2018-02-23 21:28:19 -05:00
Sergey Fedorov e60c24cecf
tcg: Clean up direct block chaining data fields
Briefly describe in a comment how direct block chaining is done. It
should help in understanding of the following data fields.

Rename some fields in TranslationBlock and TCGContext structures to
better reflect their purpose (dropping excessive 'tb_' prefix in
TranslationBlock but keeping it in TCGContext):
tb_next_offset => jmp_reset_offset
tb_jmp_offset => jmp_insn_offset
tb_next => jmp_target_addr
jmp_next => jmp_list_next
jmp_first => jmp_list_first

Avoid using a magic constant as an invalid offset which is used to
indicate that there's no n-th jump generated.

Backports commit f309101c26b59641fc1aa8fb2a98a5441cdaea03 from qemu
2018-02-23 21:28:19 -05:00
Richard Henderson bb0b055a99
translate-all: Adjust 256mb testing for mips64
Make sure we preserve the high 32-bits when masking for mips64.

Backports commit 7ba6a512ae439c98c0c1f0f4348c079d90f9dd9d from qemu
2018-02-23 21:28:19 -05:00
Emilio G. Cota de17843702
translate-all: add missing munmap of the code_gen guard page for MIPS
Backports commit 8bdf4997823126a39bd4c99e4b2283b02cc7865f from qemu
2018-02-23 21:28:19 -05:00
Emilio G. Cota 9a2b02b241
translate-all: remove redundant setting of tcg_ctx.code_gen_buffer_size
The setting of tcg_ctx.code_gen_buffer_size is done by the only caller of
size_code_gen_buffer(), which is code_gen_alloc():

$ git grep size_code_gen_buffer
translate-all.c:static inline size_t size_code_gen_buffer(size_t tb_size)
translate-all.c: tcg_ctx.code_gen_buffer_size = size_code_gen_buffer(tb_size);

Backports commit 835154b6e2200460f04719d0028716a37c178368 from qemu
2018-02-23 21:28:19 -05:00
Sergey Fedorov c5b234ed1f
tcg: Note requirement on atomic direct jump patching
Backports commit 10b4f4855537dd421e193a7d0416513116370558 from qemu
2018-02-23 21:28:18 -05:00
Sergey Fedorov 87c3382dc8
tcg/mips: Make direct jump patching thread-safe
Ensure direct jump patching in MIPS is atomic by using
atomic_read()/atomic_set() for code patching.

Backports commit c82460a560176ef69c2f0662bd280612e274db96 from qemu
2018-02-23 21:28:18 -05:00
Sergey Fedorov 7538001da9
tcg/sparc: Make direct jump patching thread-safe
Ensure direct jump patching in SPARC is atomic by using
atomic_read()/atomic_set() for code patching.

Backports commit 84f79fb7c6e857edc807e4a251338243ce0cbac3 from qemu
2018-02-23 21:28:18 -05:00
Sergey Fedorov a45f8cb49d
tcg/aarch64: Make direct jump patching thread-safe
Ensure direct jump patching in AArch64 is atomic by using
atomic_read()/atomic_set() for code patching.

Backports commit 9e269112953be4d670cb0d25042bd6546fcf3e45 from qemu
2018-02-23 21:28:18 -05:00
Sergey Fedorov 52e2972300
tcg/arm: Make direct jump patching thread-safe
Ensure direct jump patching in ARM is atomic by using
atomic_read()/atomic_set() for code patching.

Backports commit 7d14e0e2d661479985197203589c38840e1066df from qemu
2018-02-23 21:28:18 -05:00
Sergey Fedorov 57359fbe6c
tcg/s390: Make direct jump patching thread-safe
Ensure direct jump patching in s390 is atomic by:
* naturally aligning a location of direct jump address;
* using atomic_read()/atomic_set() for code patching.

Backports commit ed3d51ecd7fe248d3959e469d53890ac9ffe0cd2 from qemu
2018-02-23 21:28:18 -05:00
Sergey Fedorov 5eb2d6618f
tcg/i386: Make direct jump patching thread-safe
Ensure direct jump patching in i386 is atomic by:
* naturally aligning a location of direct jump address;
* using atomic_read()/atomic_set() for code patching.

Backports commit 0d07abf05e98903c7faf204a9a90f7d45b7554dc from qemu
2018-02-23 21:28:17 -05:00
Lioncash fffa27d269
osdep: MSVC-compatible alignment macros 2018-02-23 21:28:17 -05:00
Sergey Fedorov 3456f0879e
include/qemu/osdep.h: Add macros for pointer alignment
These macros provide a convenient way to n-byte align pointers up and
down and check if a pointer is n-byte aligned.

Backports commit 6b587d3cda48e7ba26de8d30bf0d8a7063970715 from qemu
2018-02-23 21:28:17 -05:00
Sergey Fedorov 47eac70cb9
include/qemu/osdep.h: Add a macro to check for alignment
Backports commit 18a60a76147569ca9e11b0607e50ce4012fe1aaa from qemu
2018-02-23 21:28:17 -05:00
Emilio G. Cota 170f6e0b3b
tb: consistently use uint32_t for tb->flags
We are inconsistent with the type of tb->flags: usage varies loosely
between int and uint64_t. Settle to uint32_t everywhere, which is
superior to both: at least one target (aarch64) uses the most significant
bit in the u32, and uint64_t is wasteful.

Compile-tested for all targets.

Backports commit 89fee74a0f066dfd73830a7b5fa137e87888c870 from qemu
2018-02-23 21:28:11 -05:00
Peter Maydell fe2000aa32
target-arm: Avoid unnecessary TLB flush on TCR_EL2, TCR_EL3 writes
The TCR_EL2 and TCR_EL3 regdefs were incorrectly using the
vmsa_tcr_el1_write function for writes. Since these registers don't
have the A1 bit that TCR_EL1 does, we don't need to do a tlb_flush()
when they are written. Remove the unnecessary .writefn and also the
harmless but unneeded .raw_writefn and .resetfn definitions.

Backports commit 6459b94c26dd666badb3547fef1456992a08e60b from qemu
2018-02-23 20:09:12 -05:00
Edgar E. Iglesias eb79db28d5
target-arm/translate-a64.c: Unify some of the ldst_reg decoding
The various load/store variants under disas_ldst_reg can all reuse the
same decoding for opc, size, rt and is_vector.

This patch unifies the decoding in preparation for generating
instruction syndromes for data aborts.
This will allow us to reduce the number of places to hook in updates
to the load/store state needed to generate the insn syndromes.

No functional change.

Backports commit cd694521ca061a5d0436d5df4ec8c17c8f4dfcdb from qemu
2018-02-23 20:06:31 -05:00
Edgar E. Iglesias 602e9e34b9
target-arm/translate-a64.c: Use extract32 in disas_ldst_reg_imm9
Use extract32 instead of open coding the bit masking when decoding
is_signed and is_extended. This streamlines the decoding with some
of the other ldst variants.

No functional change.

Backports commit 026a19c3128678d4fe301fc36e8ffacdc9ecccb8 from qemu
2018-02-23 20:04:11 -05:00
Peter Maydell 56e9d7c09e
target-arm: Split data abort syndrome generator
Split the data abort syndrome generator into two versions:
One with a valid Instruction Specific Syndrome (ISS) and another without.

The following new flags are supported by the syndrome generator
with ISS:
* isv - Instruction syndrome valid
* sas - Syndrome access size
* sse - Syndrome sign extend
* srt - Syndrome register transfer
* sf - Sixty-Four bit register width
* ar - Acquire/Release

These flags are not yet used, so this patch has no functional change
except that we will now correctly set the IL bit in data abort
syndromes without ISS information.

Backports commit 094d028a7968236cd2b7f7b96394f7a3b8ad97c8 from qemu
2018-02-23 20:03:04 -05:00
Edgar E. Iglesias bfc74c4da2
gen-icount: Use tcg_set_insn_param
Use tcg_set_insn_param() instead of directly accessing internal
tcg data structures to update an insn param.

Backports commit 25caa94c4a26daaab1e65c6d887e2972aeb5749e from qemu
2018-02-23 20:01:17 -05:00
Edgar E. Iglesias a30a478538
tcg: Add tcg_set_insn_param
Add tcg_set_insn_param as a mechanism to modify an insn
parameter after emiting the insn. This is useful for icount
and also for embedding fault information for a specific insn.

Backports commit 1d41478fd428e01f057d3248292e4cdcdb048523 from qemu
2018-02-23 19:58:49 -05:00
Sergey Sorokin 98a6d44c54
target-arm: Fix descriptor address masking in ARM address translation
There is a bug in ARM address translation regime with a long-descriptor
format. On the descriptor reading its address is formed from an index
which is a part of the input address. And on the first iteration this index
is incorrectly masked with 'grainsize' mask. But it can be wider according
to pseudo-code.
On the other hand on the iterations other than first the descriptor address
is formed from the previous level descriptor by masking with 'descaddrmask'
value. It always clears just 12 lower bits, but it must clear 'grainsize'
lower bits instead according to pseudo-code.
The patch fixes both cases.

Backports commit dddb5223413c5425ae6eaeb3b967627efc9675f7 from qemu
2018-02-23 19:56:56 -05:00
Sergey Sorokin 00e751f18e
target-arm: Stage 2 permission fault was fixed in AArch32 state
As described in AArch32.CheckS2Permission an instruction fetch fails if
XN bit is set or there is no read permission for the address.

Backports commit dfda68377e20943f474505e75238cb96bc6874bf from qemu
2018-02-23 19:55:11 -05:00
Eric Blake 2f42c2c195
qapi: Change visit_type_FOO() to no longer return partial objects
Returning a partial object on error is an invitation for a careless
caller to leak memory. We already fixed things in an earlier
patch to guarantee NULL if visit_start fails ("qapi: Guarantee
NULL obj on input visitor callback error"), but that does not
help the case where visit_start succeeds but some other failure
happens before visit_end, such that we leak a partially constructed
object outside visit_type_FOO(). As no one outside the testsuite
was actually relying on these semantics, it is cleaner to just
document and guarantee that ALL pointer-based visit_type_FOO()
functions always leave a safe value in *obj during an input visitor
(either the new object on success, or NULL if an error is
encountered), so callers can now unconditionally use
qapi_free_FOO() to clean up regardless of whether an error occurred.

The decision is done by adding visit_is_input(), then updating the
generated code to check if additional cleanup is needed based on
the type of visitor in use.

Note that we still leave *obj unchanged after a scalar-based
visit_type_FOO(); I did not feel like auditing all uses of
visit_type_Enum() to see if the callers would tolerate a specific
sentinel value (not to mention having to decide whether it would
be better to use 0 or ENUM__MAX as that sentinel).

Backports commit 68ab47e4b4ecc1c4649362b8cc1e49794d1a6537 from qemu
2018-02-23 19:53:17 -05:00
Eric Blake 0d52542da2
qapi: Simplify semantics of visit_next_list()
The semantics of the list visit are somewhat baroque, with the
following pseudocode when FooList is used:

start()
for (prev = head; cur = next(prev); prev = &cur) {
visit(&cur->value)
}

Note that these semantics (advance before visit) requires that
the first call to next() return the list head, while all other
calls return the next element of the list; that is, every visitor
implementation is required to track extra state to decide whether
to return the input as-is, or to advance. It also requires an
argument of 'GenericList **' to next(), solely because the first
iteration might need to modify the caller's GenericList head, so
that all other calls have to do a layer of dereferencing.

Thankfully, we only have two uses of list visits in the entire
code base: one in spapr_drc (which completely avoids
visit_next_list(), feeding in integers from a different source
than uint8List), and one in qapi-visit.py. That is, all other
list visitors are generated in qapi-visit.c, and share the same
paradigm based on a qapi FooList type, so we can refactor how
lists are laid out with minimal churn among clients.

We can greatly simplify things by hoisting the special case
into the start() routine, and flipping the order in the loop
to visit before advance:

start(head)
for (tail = *head; tail; tail = next(tail)) {
visit(&tail->value)
}

With the simpler semantics, visitors have less state to track,
the argument to next() is reduced to 'GenericList *', and it
also becomes obvious whether an input visitor is allocating a
FooList during visit_start_list() (rather than the old way of
not knowing if an allocation happened until the first
visit_next_list()). As a minor drawback, we now allocate in
two functions instead of one, and have to pass the size to
both functions (unless we were to tweak the input visitors to
cache the size to start_list for reuse during next_list, but
that defeats the goal of less visitor state).

The signature of visit_start_list() is chosen to match
visit_start_struct(), with the new parameters after 'name'.

The spapr_drc case is a virtual visit, done by passing NULL for
list, similarly to how NULL is passed to visit_start_struct()
when a qapi type is not used in those visits. It was easy to
provide these semantics for qmp-output and dealloc visitors,
and a bit harder for qmp-input (several prerequisite patches
refactored things to make this patch straightforward). But it
turned out that the string and opts visitors munge enough other
state during visit_next_list() to make it easier to just
document and require a GenericList visit for now; an assertion
will remind us to adjust things if we need the semantics in the
future.

Several pre-requisite cleanup patches made the reshuffling of
the various visitors easier; particularly the qmp input visitor.

Backports commit d9f62dde1303286b24ac8ce88be27e2b9b9c5f46 from qemu
2018-02-23 19:50:26 -05:00
Lioncash ed72ba0f8b
qapi: Fix string input visitor handling of invalid list
As shown in the previous commit, the string input visitor was
treating bogus input as an empty list rather than an error.
Fix parse_str() to set errp, then the callers to exit early if
an error was reported.

Meanwhile, fix the testsuite to use the generated
qapi_free_int16List() instead of rolling our own, and to
validate the fixed behavior, while at the same time documenting
one more change that we'd like to make in a later patch (a
failed visit_start_list should guarantee a NULL pointer,
regardless of what things were on input).

Backports commit 74f24cb6306d065045d0e2215a7d10533fa59c57 from qemu
2018-02-23 19:25:26 -05:00
Eric Blake 6084be1882
qapi: Split visit_end_struct() into pieces
As mentioned in previous patches, we want to call visit_end_struct()
functions unconditionally, so that visitors can release resources
tied up since the matching visit_start_struct() without also having
to worry about error priority if more than one error occurs.

Even though error_propagate() can be safely used to ignore a second
error during cleanup caused by a first error, it is simpler if the
cleanup cannot set an error. So, split out the error checking
portion (basically, input visitors checking for unvisited keys) into
a new function visit_check_struct(), which can be safely skipped if
any earlier errors are encountered, and leave the cleanup portion
(which never fails, but must be called unconditionally if
visit_start_struct() succeeded) in visit_end_struct().

Generated code in qapi-visit.c has diffs resembling:

|@@ -59,10 +59,12 @@ void visit_type_ACPIOSTInfo(Visitor *v,
| goto out_obj;
| }
| visit_type_ACPIOSTInfo_members(v, obj, &err);
|- error_propagate(errp, err);
|- err = NULL;
|+ if (err) {
|+ goto out_obj;
|+ }
|+ visit_check_struct(v, &err);
| out_obj:
|- visit_end_struct(v, &err);
|+ visit_end_struct(v);
| out:

and in qapi-event.c:

@@ -47,7 +47,10 @@ void qapi_event_send_acpi_device_ost(ACP
| goto out;
| }
| visit_type_q_obj_ACPI_DEVICE_OST_arg_members(v, &param, &err);
|- visit_end_struct(v, err ? NULL : &err);
|+ if (!err) {
|+ visit_check_struct(v, &err);
|+ }
|+ visit_end_struct(v);
| if (err) {
| goto out;

Backports commit 15c2f669e3fb2bc97f7b42d1871f595c0ac24af8 from qemu
2018-02-23 19:13:47 -05:00
Eric Blake ae8d475ae0
qmp: Tighten output visitor rules
Tighten assertions in the QMP output visitor, so that:

- qmp_output_get_qobject() can only be called after pairing a
visit_end_* for every visit_start_* (rather than allowing it on
a partially built object)

- qmp_output_get_qobject() cannot be called unless at least one
visit_type_* or visit_start/visit_end pair has occurred since
creation/reset (the accidental return of NULL fixed by commit
ab8bf1d7 would have been much easier to diagnose)

- ensure that we are encountering the expected object or list
type, to provide protection against mismatched push(struct)/
pop(list) or push(list)/pop(struct), similar to the qmp-input
protection added in commit bdd8e6b5.

- ensure that except for the root, 'name' is non-null inside a
dict, and NULL inside a list (this may need changing later if
we add "name.0" support for better error messages for a list,
but for now it makes sure all users are at least consistent)

Backports commit 56a6f02b8ce1fe41a2a9077593e46eca7d98267d from qemu
2018-02-23 19:04:41 -05:00
Eric Blake e5b2cff2bd
qmp: Support explicit null during visits
Implement the new type_null() callback for the qmp input and
output visitors. While we don't yet have a use for this in QAPI
input (the generator will need some tweaks first), some
potential usages have already been discussed on the list.
Meanwhile, the output visitor could already output explicit null
via type_any, but this gives us finer control.

At any rate, it's easy to test that we can round-trip an explicit
null through manual use of visit_type_null() wrapped by a virtual
visit_start_struct() walk, even if we can't do the visit in a
QAPI type. Repurpose the test_visitor_out_empty test,
particularly since a future patch will tighten semantics to
forbid use of qmp_output_get_qobject() without at least one
intervening visit_type_*.

Backports commit 3df016f185521f8dfa5bd89168722887156405c7 from qemu
2018-02-23 19:02:18 -05:00
Eric Blake ef6b7b50f6
qapi: Add visit_type_null() visitor
Right now, qmp-output-visitor happens to produce a QNull result
if nothing is actually visited between the creation of the visitor
and the request for the resulting QObject. A stronger protocol
would require that a QMP output visit MUST visit something. But
to still be able to produce a JSON 'null' output, we need a new
visitor function that states our intentions. Yes, we could say
that such a visit must go through visit_type_any(), but that
feels clunky.

So this patch introduces the new visit_type_null() interface and
its no-op interface in the dealloc visitor, and stubs in the
qmp visitors (the next patch will finish the implementation).
For the visitors that will not implement the callback, document
the situation. The code in qapi-visit-core unconditionally
dereferences the callback pointer, so that a segfault will inform
a developer if they need to implement the callback for their
choice of visitor.

Note that JSON has a primitive null type, with the single value
null; likewise with the QNull type for QObject; but for QAPI,
we just have the 'null' value without a null type. We may
eventually want to add more support in QAPI for null (most likely,
we'd use it via an alternate type that permits 'null' or an
object); but we'll create that usage when we need it.

Backports commit 3bc97fd5924561d92f32758c67eaffd2e4e25038 from qemu
2018-02-23 15:48:57 -05:00
Eric Blake fafb3e354b
qapi: Document visitor interfaces, add assertions
The visitor interface for mapping between QObject/QemuOpts/string
and QAPI is scandalously under-documented, making changes to visitor
core, individual visitors, and users of visitors difficult to
coordinate. Among other questions: when is it safe to pass NULL,
vs. when a string must be provided; which visitors implement which
callbacks; the difference between concrete and virtual visits.

Correct this by retrofitting proper contracts, and document where some
of the interface warts remain (for example, we may want to modify
visit_end_* to require the same 'obj' as the visit_start counterpart,
so the dealloc visitor can be simplified). Later patches in this
series will tackle some, but not all, of these warts.

Add assertions to (partially) enforce the contract. Some of these
were only made possible by recent cleanup commits.

Backports commit adfb264c9ed04bfc694921b72173be8e29e90024 from qemu
2018-02-23 15:45:31 -05:00
Eric Blake 9e999acc83
qapi: Change visit_start_implicit_struct to visit_start_alternate
After recent changes, the only remaining use of
visit_start_implicit_struct() is for allocating the space needed
when visiting an alternate. Since the term 'implicit struct' is
hard to explain, rename the function to its current usage. While
at it, we can merge the functionality of visit_get_next_type()
into the same function, making it more like visit_start_struct().

Generated code is now slightly smaller:

| {
| Error *err = NULL;
|
|- visit_start_implicit_struct(v, (void**) obj, sizeof(BlockdevRef), &err);
|+ visit_start_alternate(v, name, (GenericAlternate **)obj, sizeof(**obj),
|+ true, &err);
| if (err) {
| goto out;
| }
|- visit_get_next_type(v, name, &(*obj)->type, true, &err);
|- if (err) {
|- goto out_obj;
|- }
| switch ((*obj)->type) {
| case QTYPE_QDICT:
| visit_start_struct(v, name, NULL, 0, &err);
...
| }
|-out_obj:
|- visit_end_implicit_struct(v);
|+ visit_end_alternate(v);
| out:
| error_propagate(errp, err);
| }

Backports commit dbf11922622685934bfb41e7cf2be9bd4a0405c0 from qemu
2018-02-23 15:33:25 -05:00
Eric Blake 5389c1cd5f
qmp-input: Refactor when list is advanced
In the QMP input visitor, visiting a list traverses two objects:
the QAPI GenericList of the caller (which gets advanced in
visit_next_list() regardless of this patch), and the QList input
that we are converting to QAPI. For consistency with QDict
visits, we want to consume elements from the input QList during
the visit_type_FOO() for the list element; that is, we want ALL
the code for consuming an input to live in qmp_input_get_object(),
rather than having it split according to whether we are visiting
a dict or a list. Making qmp_input_get_object() the common point
of consumption will make it easier for a later patch to refactor
visit_start_list() to cover the GenericList * head of a QAPI list,
and in turn will get rid of the 'first' flag (which lived in
qmp_input_next_list() pre-patch, and is hoisted to StackObject
by this patch).

This patch is therefore altering the post-condition use of 'entry',
while keeping what gets visited unchanged, from:

start_list next_list type_ELT ... next_list type_ELT next_list end_list
visits 1st elt last elt
entry NULL 1st elt 1st elt last elt last elt NULL gone

where type_ELT() returns (entry ? entry : 1st elt) and next_list() steps
entry

to this usage:

start_list next_list type_ELT ... next_list type_ELT next_list end_list
visits 1st elt last elt
entry 1st elt 1nd elt 2nd elt last elt NULL NULL gone

where type_ELT() steps entry and returns the old entry, and next_list()
leaves entry alone.

Backports commit fcf3cb21783b2dae3358fdbe7001cb2f74e0cedf from qemu
2018-02-23 15:19:40 -05:00
Eric Blake 68cf25fafa
qmp-input: Require struct push to visit members of top dict
Don't embed the root of the visit into the stack of current
containers being visited. That way, we no longer get confused
on whether the first visit of a dictionary is to the dictionary
itself or to one of the members of the dictionary, based on
whether the caller passed name=NULL; and makes the QMP Input
visitor like other visitors where the value of 'name' is now
ignored on the root visit. (We may someday want to revisit
the rules on what 'name' should be on a top-level visit,
rather than just ignoring it; but that would be the topic of
another patch).

An audit of all qmp_input_visitor_new() call sites shows that
there were only two places where callers had previously been
visiting to a QDict with a non-NULL name to bypass a call to
visit_start_struct(), and those were fixed in prior patches.

Backports commit ce140b176920b5b65184020735a3c65ed3e9aeda from qemu
2018-02-23 15:16:43 -05:00
Eric Blake 1bb4e4c787
qmp-input: Don't consume input when checking has_member
Commit e8316d7 mistakenly passed consume=true within
qmp_input_optional() when checking if an optional member was
present, but the mistake was silently ignored since the code
happily let us extract a member more than once. Fix
qmp_input_optional() to not consume anything, then tighten up
the input visitor to ensure that a member is consumed exactly
once (all generated code follows this pattern; and the new
assert will catch any hand-written code that tries to visit
the same key more than once).

Backports commit e5826a2fd727f0be54a81083f31fe02a275465cd from qemu
2018-02-23 15:12:58 -05:00
Eric Blake cae9c2bd2d
qapi: Use strict QMP input visitor in more places
The following uses of a QMP input visitor should be strict
(that is, excess keys in QDict input should be flagged if not
converted to QAPI):

- Testsuite code unrelated to explicitly testing non-strict
mode (test-qmp-commands, test-visitor-serialization); since
we want more code to be strict by default, having more tests
of strict mode doesn't hurt

- Code used for cloning QAPI objects (replay-input.c,
qemu-sockets.c); we are reparsing a QObject just barely
produced by the qmp output visitor and which therefore should
not have any garbage, so while it is extra work to be strict,
it validates that our clone is correct [note that a later patch
series will simplify these two uses by creating an actual
clone visitor that is much more efficient than a
generate/reparse cycle]

- qmp_object_add(), which calls into user_creatable_add_type().
Since command line parsing for '-object' uses the same
user_creatable_add_type() through the OptsVisitor, and that is
always strict, we want to ensure that any nested dictionaries
would be treated the same in QMP and from the command line (I
don't actually know if such nested dictionaries exist). Note
that on this code change, strictness only matters for nested
dictionaries (if even possible), since we already flag excess
input at the top level during an earlier object_property_set()
on an unknown key, whether from QemuOpts:

$ ./x86_64-softmmu/qemu-system-x86_64 -nographic -nodefaults -qmp stdio -object secret,id=sec0,data=letmein,format=raw,foo=bar
qemu-system-x86_64: -object secret,id=sec0,data=letmein,format=raw,foo=bar: Property '.foo' not found

or from QMP:

$ ./x86_64-softmmu/qemu-system-x86_64 -nographic -nodefaults -qmp stdio
{"QMP": {"version": {"qemu": {"micro": 93, "minor": 5, "major": 2}, "package": ""}, "capabilities": []}}
{"execute":"qmp_capabilities"}
{"return": {}}
{"execute":"object-add","arguments":{"qom-type":"secret","id":"sec0","props":{"format":"raw","data":"letmein","foo":"bar"}}}
{"error": {"class": "GenericError", "desc": "Property '.foo' not found"}}

The only remaining uses of non-strict input visits are:

- QMP 'qom-set' (which eventually executes
object_property_set_qobject()) - mark it as something to revisit
in the future (I didn't want to spend any more time on this patch
auditing if we have any QOM dictionary properties that might be
impacted, and couldn't easily prove whether this code path is
shared with anything else).

- test-qmp-input-visitor: explicit tests of non-strict mode. If
we later get rid of users that don't need strictness, then this
test should be merged with test-qmp-input-strict

Backports relevant parts of commit 240f64b6dc3346d044d7beb7cc3a53668ce47384 from qemu
2018-02-23 15:11:35 -05:00
Eric Blake 559304aed9
qapi: Consolidate QMP input visitor creation
Rather than having two separate ways to create a QMP input
visitor, where the safer approach has the more verbose name,
it is better to consolidate things into a single function
where the caller must explicitly choose whether to be strict
or to ignore excess input. This patch is the strictly
mechanical conversion; the next patch will then audit which
uses can be made stricter.

Backports commit fc471c18d5d2ec713d5a019f9530398675494bc8 from qemu
2018-02-23 15:09:57 -05:00
Eric Blake b1c4558849
qmp-input: Clean up stack handling
Management of the top of stack was a bit verbose; creating a
temporary variable and adding some comments makes the existing
code more legible before the next few patches improve things.
No semantic changes other than asserting that we are always
visiting a QObject, and not a NULL value. In particular, the
check for 'name && qobject_type(qobj) == QTYPE_QDICT)' is a
bit overkill (a dict visit should always have a name); a later
patch revisits that, while this patch is only changing one
layer of indentation due to dropping 'if (qobj)'.

Backports commit b471d012e5d7bec1d2272738141e121b5581fcdf from qemu
2018-02-23 15:08:14 -05:00
Eric Blake 0ec9a5adaf
qapi: Guarantee NULL obj on input visitor callback error
Our existing input visitors were not very consistent on errors in a
function taking 'TYPE **obj'. These are start_struct(),
start_alternate(), type_str(), and type_any(). next_list() is
similar, but can't fail (see commit 08f9541). While all of them set
'*obj' to allocated storage on success, it was not obvious whether
'*obj' was guaranteed safe on failure, or whether it was left
uninitialized. But a future patch wants to guarantee that
visit_type_FOO() does not leak a partially-constructed obj back to
the caller; it is easier to implement this if we can reliably state
that input visitors assign '*obj' regardless of success or failure,
and that on failure *obj is NULL. Add assertions to enforce
consistency in the final setting of err vs. *obj.

The opts-visitor start_struct() doesn't set an error, but it
also was doing a weird check for 0 size; all callers pass in
non-zero size if obj is non-NULL.

The testsuite has at least one spot where we no longer need
to pre-initialize a variable prior to a visit; valgrind confirms
that the test is still fine with the cleanup.

A later patch will document the design constraint implemented
here.

Backports commit e58d695e6c3a5cfa0aa2fc91b87ade017ef28b05 from qemu
2018-02-23 14:53:23 -05:00
Eric Blake 3cf7b6dd3b
qapi: Adjust layout of FooList types
By sticking the next pointer first, we don't need a union with
64-bit padding for smaller types.  On 32-bit platforms, this
can reduce the size of uint8List from 16 bytes (or 12, depending
on whether 64-bit ints can tolerate 4-byte alignment) down to 8.
It has no effect on 64-bit platforms (where alignment still
dictates a 16-byte struct); but fewer anonymous unions is still
a win in my book.

It requires visit_next_list() to gain a size parameter, to know
what size element to allocate; comparable to the size parameter
of visit_start_struct().

I debated about going one step further, to allow for fewer casts,
by doing:
    typedef GenericList GenericList;
    struct GenericList {
        GenericList *next;
    };
    struct FooList {
        GenericList base;
        Foo *value;
    };
so that you convert to 'GenericList *' by '&foolist->base', and
back by 'container_of(generic, GenericList, base)' (as opposed to
the existing '(GenericList *)foolist' and '(FooList *)generic').
But doing that would require hoisting the declaration of
GenericList prior to inclusion of qapi-types.h, rather than its
current spot in visitor.h; it also makes iteration a bit more
verbose through 'foolist->base.next' instead of 'foolist->next'.

Note that for lists of objects, the 'value' payload is still
hidden behind a boxed pointer.  Someday, it would be nice to do:

struct FooList {
    FooList *next;
    Foo value;
};

for one less level of malloc for each list element.  This patch
is a step in that direction (now that 'next' is no longer at a
fixed non-zero offset within the struct, we can store more than
just a pointer's-worth of data as the value payload), but the
actual conversion would be a task for another series, as it will
touch a lot of code.

Backports commit e65d89bf1a4484e0db0f3dc820a8b209f2fb1e8b from qemu
2018-02-23 14:49:06 -05:00
Eric Blake eef0932471
qapi-visit: Add visitor.type classification
We have three classes of QAPI visitors: input, output, and dealloc.
Currently, all implementations of these visitors have one thing in
common based on their visitor type: the implementation used for the
visit_type_enum() callback. But since we plan to add more such
common behavior, in relation to documenting and further refining
the semantics, it makes more sense to have the visitor
implementations advertise which class they belong to, so the common
qapi-visit-core code can use that information in multiple places.

A later patch will better document the types of visitors directly
in visitor.h.

For this patch, knowing the class of a visitor implementation lets
us make input_type_enum() and output_type_enum() become static
functions, by replacing the callback function Visitor.type_enum()
with the simpler enum member Visitor.type. Share a common
assertion in qapi-visit-core as part of the refactoring.

Move comments in opts-visitor.c to match the refactored layout.

Backports commit 983f52d4b3f86fb9dc9f8b142132feb5a8723016 from qemu
2018-02-23 14:25:41 -05:00
Dave Hansen f50acc467f
target-i386: fix typo in xsetbv implementation
QEMU 2.6 added support for the XSAVE family of instructions, which
includes the XSETBV instruction which allows setting the XCR0
register.

But, when booting Linux kernels with XSAVE support enabled, I was
getting very early crashes where the instruction pointer was set
to 0x3. I tracked it down to a jump instruction generated by this:

gen_jmp_im(s->pc - pc_start);

where s->pc is pointing to the instruction after XSETBV and pc_start
is pointing _at_ XSETBV. Subtract the two and you get 0x3. Whoops.

The fix is to replace this typo with the pattern found everywhere
else in the file when folks want to end the translation buffer.

Richard Henderson confirmed that this is a bug and that this is the
correct fix.

Backports commit 502c8e86ea07294067578292c6d402601c196019 from qemu
2018-02-23 14:15:35 -05:00
Fam Zheng 5c739f14f5
util: Fix MIN_NON_ZERO
MIN_NON_ZERO(1, 0) is evaluated to 0. Rewrite the macro to fix it.

Backports commit b6ece2c6f37926a994bc564a9e55ef3be6016d8f from qemu
2018-02-23 14:09:44 -05:00
Artyom Tarasenko 1781d5cfa6
target-sparc: fix register corruption in ldstub if there is no write permission
Backports commit 9566ceeef41ccb5241d340b34776a33450e8f9e5 from qemu
2018-02-23 14:06:38 -05:00
Paolo Bonzini 44c4dd02c9
target-i386: key sfence availability on CPUID_SSE, not CPUID_SSE2
sfence was introduced before lfence and mfence. This fixes Linux
2.4's measurement of checksumming speeds for the pIII_sse
algorithm:

md: linear personality registered as nr 1
md: raid0 personality registered as nr 2
md: raid1 personality registered as nr 3
md: raid5 personality registered as nr 4
raid5: measuring checksumming speed
8regs : 384.400 MB/sec
32regs : 259.200 MB/sec
invalid operand: 0000
CPU: 0
EIP: 0010:[<c0240b2a>] Not tainted
EFLAGS: 00000246
eax: c15d8000 ebx: 00000000 ecx: 00000000 edx: c15d5000
esi: 8005003b edi: 00000004 ebp: 00000000 esp: c15bdf50
ds: 0018 es: 0018 ss: 0018
Process swapper (pid: 1, stackpage=c15bd000)
Stack: 00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000
00000000 00000000 00000000 00000000 00000000 00000000 00000000
00000000
00000000 00000206 c0241c6c 00001000 c15d4000 c15d7000 c15d4000
c15d4000
Call Trace: [<c0241c6c>] [<c0105000>] [<c0241db4>] [<c010503b>]
[<c0105000>]
[<c0107416>] [<c0105030>]

Code: 0f ae f8 0f 10 04 24 0f 10 4c 24 10 0f 10 54 24 20 0f 10 5c
<0>Kernel panic: Attempted to kill init!

Backports commit bd5d278668f33aa08755a982986cd1159746c037 from qemu
2018-02-23 14:03:19 -05:00
Aurelien Jarno 0c4bebb9bc
target-mips: fix call to memset in soft reset code
Recent versions of GCC report the following error when compiling
target-mips/helper.c:

qemu/target-mips/helper.c:542:9: warning: ‘memset’ used with length
equal to number of elements without multiplication by element size
[-Wmemset-elt-size]

Backports commit a525decfaa3449f1458ea2d7a06320cf46aebf3f from qemu
2018-02-23 14:01:50 -05:00
James Hogan e4903fc5f2
target-mips: Fix RDHWR exception host PC
Commit b00c72180c36 ("target-mips: add PC, XNP reg numbers to RDHWR")
changed the rdhwr helpers to use check_hwrena() to check the register
being accessed is enabled in CP0_HWREna when used from user mode. If
that check fails an EXCP_RI exception is raised at the host PC
calculated with GETPC().

However check_hwrena() may not be fully inlined as the
do_raise_exception() part of it is common regardless of the arguments.
This causes GETPC() to calculate the address in the call in the helper
instead of the generated code calling the helper. No TB will be found
and the EPC reported with the resulting guest RI exception points to the
beginning of the TB instead of the RDHWR instruction.

We can't reliably force check_hwrena() to be inlined, and converting it
to a macro would be ugly, so instead pass the host PC in as an argument,
with each rdhwr helper passing GETPC(). This should avoid any dependence
on compiler behaviour, and in practice seems to ensure the full inlining
of check_hwrena() on x86_64.

This issue causes failures when running a MIPS KVM (trap & emulate)
guest in a MIPS QEMU TCG guest, as the inner guest kernel will do a
RDHWR of counter, which is disabled in the outer guest's CP0_HWREna by
KVM so it can emulate the inner guest's counter. The emulation fails and
the RI exception is passed to the inner guest.

Backports commit d96391c1ffeb30a0afa695c86579517c69d9a889 from qemu
2018-02-23 13:59:37 -05:00
Christoffer Dall 6180cbd477
util: align memory allocations to 2M on AArch64
For KVM to use Transparent Huge Pages (THP) we have to ensure that the
alignment of the userspace address of the KVM memory slot and the IPA
that the guest sees for a memory region have the same offset from the 2M
huge page size boundary.

One way to achieve this is to always align the IPA region at a 2M
boundary and ensure that the mmap alignment is also at 2M.

Unfortunately, we were only doing this for __arm__, not for __aarch64__,
so add this simple condition.

This fixes a performance regression using KVM/ARM on AArch64 platforms
that showed a performance penalty of more than 50%, introduced by the
following commit:

9fac18f (oslib: allocate PROT_NONE pages on top of RAM, 2015-09-10)

We were only lucky before the above commit, because we were allocating
large regions and naturally getting a 2M alignment on those allocations
then.

Backports commit ee1e0f8e5d3682c561edcdceccff72b9d9b16d8b from qemu
2018-02-23 13:56:59 -05:00
Aurelien Jarno 6060ab6596
tcg: check for CONFIG_DEBUG_TCG instead of NDEBUG
Check for CONFIG_DEBUG_TCG instead of NDEBUG, drop now useless code.

Backports commit 8d8fdbae010aa75a23f0307172e81034125aba6e from qemu
2018-02-23 13:55:21 -05:00
Aurelien Jarno 355ed7cd08
tcg: use tcg_debug_assert instead of assert (fix performance regression)
The TCG code is quite performance sensitive, but at the same time can
also be quite tricky. That is why asserts that can be enabled with the
--enable-debug-tcg configure option.

This used to work the following way:

| #include "config.h"
|
| ...
|
| #if !defined(CONFIG_DEBUG_TCG) && !defined(NDEBUG)
| /* define it to suppress various consistency checks (faster) */
| #define NDEBUG
| #endif
|
| ...
|
| #include <assert.h>

Since commit 757e725b (tcg: Clean up includes) "config.h" as been
replaced by "qemu/osdep.h" which itself includes <assert.h>. As a
consequence the assertions are always enabled, even when using
--disable-debug-tcg, causing a performance regression, especially on
targets with many registers. For instance on qemu-system-ppc the
speed difference is about 15%.

tcg_debug_assert is controlled directly by CONFIG_DEBUG_TCG and already
uses in some places. This patch replaces all the calls to assert into
calss to tcg_debug_assert.

Backports commit eabb7b91b36b202b4dac2df2d59d698e3aff197a from qemu
2018-02-23 13:52:13 -05:00
Artyom Tarasenko af0e282ab1
target-sparc: fix Trap Based Address Register behavior for sparc64
Accoding the chapter 7.6 Trap Processing of the SPARC Architecture Manual v9,
the Trap Based Address Register is not modified as a trap is taken.

This fix allows booting FreeBSD-10.3-RELEASE-sparc64.

Backports commit de5f1077446ca455342db149737bdc395a7b9882 from qemu
2018-02-23 13:39:59 -05:00
Artyom Tarasenko 34472bd6fd
target-sparc: fix Nucleus quad LDD 128 bit access for windowed registers
Fix register offset calculation when regwptr is used.

Backports commit 01a780d51a3a0851729e1747f3787a0db4d96722 from qemu
2018-02-23 13:39:34 -05:00
Mark Cave-Ayland 7dcdae9807
target-sparc: fix ldstub sign-extension bug
ldstub [addr], reg incorrectly reads a signed byte from memory which causes
problems in the 32-bit Solaris mutex code. Here the byte value being read is
0xff which is incorrectly sign-extended to 0xffffffff before being written back
to the target register causing lock detection to behave incorrectly.

This fixes the intermittent hangs and MUTEX_HELD warnings issued to the
console when running 32-bit Solaris images under qemu-system-sparc.

With thanks to Joseph Dery for providing a condensed test image to consistently
reproduce the problem on demand, and Martin Husemann for allowing me access to
real hardware for comparison.

Backports commit 4553e10360a0713e31647220ed396942f9a6fca0 from qemu
2018-02-23 13:37:36 -05:00
Emilio G. Cota 4cacbf212f
translate-all: add missing fold of tb_ctx into tcg_ctx
Since 5e5f07e08 "TCG: Move translation block variables
to new context inside tcg_ctx: tb_ctx" on Feb 1 2013, compilation
of usermode + TB_DEBUG_CHECK has been broken. Fix it.

Backports commit 7e6bd36d61129feb7f667cb09ffec1b7b54b971c from qemu
2018-02-23 13:35:42 -05:00
Paolo Bonzini bdcea2bcb0
target-i386: check for PKU even for non-writable pages
Xiao Guangrong ran kvm-unit-tests on an actual machine with PKU and
found that it fails:

test pte.p pte.user pde.p pde.user pde.a pde.pse pkru.wd pkey=1 user write efer.nx cr4.pke: FAIL: error code 27 expected 7
Dump mapping: address: 0x123400000000
------L4: 2ebe007
------L3: 2ebf007
------L2: 8000000020000a5

(All failures are combinations of "pde.user pde.p pkru.wd pkey=1",
plus either "pde.pse" or "pte.p pte.user", plus one of "user cr0.wp",
"cr0.wp" or "user", plus unimportant bits such as accessed/dirty or
efer.nx).

So PFEC.PKEY is set even if the ordinary check failed (which it did
because pde.w is zero). Adjust QEMU to match behavior of silicon.

Backports commit 44d066a2f770ee9d61fd1c2a609bdf2a994dfdf7 from qemu
2018-02-23 13:23:37 -05:00
James Hogan 41c6079823
tcg/mips: Fix type of tcg_target_reg_alloc_order[]
The MIPS TCG backend is the only one to have
tcg_target_reg_alloc_order[] elements of type TCGReg rather than int.
This resulted in commit 91478cefaaf2 ("tcg: Allocate indirect_base
temporaries in a different order") breaking the build on MIPS since the
type differed from indirect_reg_alloc_order[]:

tcg/tcg.c:1725:44: error: pointer type mismatch in conditional expression [-Werror]
order = rev ? indirect_reg_alloc_order : tcg_target_reg_alloc_order;
^

Make it an array of ints to fix the build and match other architectures.

Backports commit 2dc7553d0c0a3915c649e1a91b0f0be70b4674b3 from qemu
2018-02-23 13:21:44 -05:00
Lioncash 88af0b0153
target-arm: Get rid of unused variable warnings 2018-02-23 12:43:09 -05:00
Lioncash 87130fc884
exec-all: Remove externs
These are unused
2018-02-23 12:43:03 -05:00
Chen Fan d0621f1852
cpu: Introduce X86CPUTopoInfo structure for argument simplification
In order to simplify arguments of function, introduce a new struct
named X86CPUTopoInfo.

Backports commit ed256144cd6f0ca2ff59fc3fc8dca547506f433b from qemu
2018-02-23 10:58:43 -05:00
Peter Crosthwaite 576f1752a6
include/exec: Move cputlb exec.c defs out
Move the architecture agnostic function prototypes for exec.c out of
cputlb.h to exec-all.h. This allows hiding of the arch specific
cputlb.h from exec.c which should be getting close to having no
architecture specifics. Prepares support for multi-arch, which will have
a minimal cpu.h that services exec.c but not cputlb.h.

Backports commit dfccc7602374c9fd3b083208b552d62daa244811 from qemu
2018-02-23 10:52:25 -05:00
Peter Crosthwaite 97c9423ee8
cputlb: move CPU_LOOP() for tlb_reset() to exec.c
To prepare for multi-arch, cputlb.c should only have awareness of one
single architecture. This means it should not have access to the full
CPU lists which may be heterogeneous. Instead, push the CPU_LOOP() up
to the one and only caller in exec.c.

Backports commit 9a13565d52bfd321934fb44ee004bbaf5f5913a8 from qemu
2018-02-23 10:46:31 -05:00
Paolo Bonzini 9479199c6b
memory: fix usage of find_next_bit and find_next_zero_bit
The last two arguments to these functions are the last and first bit to
check relative to the base. The code was using incorrectly the first
bit and the number of bits. Fix this in cpu_physical_memory_get_dirty
and cpu_physical_memory_all_dirty. This requires a few changes in the
iteration; change the code in cpu_physical_memory_set_dirty_range to
match.

Backports commit 88c73d16ad1b6c22a2ab082064d0d521f756296a from qemu
2018-02-22 19:51:43 -05:00
Alex Bennée 171d267209
include/qemu/atomic.h: default to __atomic functions
The __atomic primitives have been available since GCC 4.7 and provide
a richer interface for describing memory ordering requirements. As a
bonus by using the primitives instead of hand-rolled functions we can
use tools such as the ThreadSanitizer which need the use of well
defined APIs for its analysis.

If we have __ATOMIC defines we exclusively use the __atomic primitives
for all our atomic access. Otherwise we fall back to the mixture of
__sync and hand-rolled barrier cases.

Backports commit a0aa44b488b3601415d55041e4619aef5f3a4ba8 from qemu
2018-02-22 16:12:59 -05:00
Paolo Bonzini 4e7259a49b
atomics: add explicit compiler fence in __atomic memory barriers
__atomic_thread_fence does not include a compiler barrier; in the
C++11 memory model, fences take effect in combination with other
atomic operations.  GCC implements this by making __atomic_load and
__atomic_store access memory as if the pointer was volatile, and
leaves no trace whatsoever of acquire and release fences in the
compiler's intermediate representation.

In QEMU, we want memory barriers to act on all memory, but at the same
time we would like to use __atomic_thread_fence for portability reasons.
Add compiler barriers manually around the __atomic_thread_fence.

Backports commit 3bbf572345c65813f86a8fc434ea1b23beb08e16 from qemu
2018-02-22 15:56:37 -05:00
Paolo Bonzini 02e3eeff40
atomic: fix position of volatile qualifier
What needs to be volatile is not the pointer, but the pointed-to
value!

Backports commit 2cbcfb281afa041a41f6e4c4da0f5c9314084604 from qemu
2018-02-22 15:52:48 -05:00
Stefan Hajnoczi e79e0881cd
memory: RCU ram_list.dirty_memory[] for safe RAM hotplug
Although accesses to ram_list.dirty_memory[] use atomics so multiple
threads can safely dirty the bitmap, the data structure is not fully
thread-safe yet.

This patch handles the RAM hotplug case where ram_list.dirty_memory[] is
grown.  ram_list.dirty_memory[] is change from a regular bitmap to an
RCU array of pointers to fixed-size bitmap blocks.  Threads can continue
accessing bitmap blocks while the array is being extended.  See the
comments in the code for an in-depth explanation of struct
DirtyMemoryBlocks.

I have tested that live migration with virtio-blk dataplane works.

Backports commit 5b82b703b69acc67b78b98a5efc897a3912719eb from qemu
2018-02-22 15:38:03 -05:00
Peter Maydell a632d1b96d
target-arm: Make the 64-bit version of VTCR do the migration
Move the ALIAS tag from VTCR_EL2 to VTCR so that we migrate the
64-bit version, as is usual. (This has no particular effect now
unless the guest wrote to the high RES0 bits of VTCR_EL2.)
Add a comment about why it's OK that we don't have the various
accessor functions that the EL1 TCR regdefs do.

Backports commit bf06c1123a427fefc2cf9cf8019578eafc19eb6f from qemu
2018-02-22 11:53:19 -05:00
Peter Maydell a93e873441
target-arm: Remove incorrect ALIAS tags from ESR_EL2 and ESR_EL3
The regdefs for the ESR_EL2 and ESR_EL3 system registers should not
be marked as ARM_CP_ALIAS, because these are the master copies; the
DFSR regdef in vmsa_pmsa_cp_reginfo[] is marked as an alias.
Remove the ALIAS tags so that these registers are correctly migrated.

Backports commit 094a7d0b9d10812d06be2c5c19288cee4603c693 from qemu
2018-02-22 11:40:20 -05:00
Peter Maydell f1b5b5cea9
target-arm: Correctly reset SCTLR_EL3 for 64-bit CPUs
The regdef for SCTRL_EL3 was incorrectly marked as being an
ARM_CP_ALIAS, with the remark that this was because the 32-bit
definition would take care of reset and migration. However the
intention for banked registers as documented in the comment in
add_cpreg_to_hashtable() is:

* 2) If ARMv8 is enabled then we can count on a 64-bit version
* taking care of the secure bank. This requires that separate
* 32 and 64-bit definitions are provided.

and so it marks the 32-bit secure banked version as an alias.
This results in the sctlr_s/sctlr_el[3] field never being reset
or migrated for a 64-bit CPU with EL3 enabled.

Fix this by removing the ARM_CP_ALIAS annotation from SCTLR_EL3.
Since this means it now needs a real reset value, move the regdef
into the same place that we define the 32-bit SCTLR.

Backports commit e24fdd238a159d830a9a65dd9b08f80fba9b9e06 from qemu
2018-02-22 11:38:16 -05:00
Leon Alrae 224cbb008a
target-mips: indicate presence of IEEE 754-2008 FPU in R6/R5+MSA CPUs
MIPS Release 6 and MIPS SIMD Architecture make it mandatory to have IEEE
754-2008 FPU which is indicated by CP1 FIR.HAS2008, FCSR.ABS2008 and
FCSR.NAN2008 bits set to 1.

In QEMU we still keep these bits cleared as there is no 2008-NaN support.
However, this now causes problems preventing from running R6 Linux with
the v4.5 kernel. Kernel refuses to execute 2008-NaN ELFs on a CPU
whose FPU does not support 2008-NaN encoding:

(...)
VFS: Mounted root (ext4 filesystem) readonly on device 8:0.
devtmpfs: mounted
Freeing unused kernel memory: 256K (ffffffff806f0000 - ffffffff80730000)
request_module: runaway loop modprobe binfmt-464c
Starting init: /sbin/init exists but couldn't execute it (error -8)
request_module: runaway loop modprobe binfmt-464c
Starting init: /bin/sh exists but couldn't execute it (error -8)
Kernel panic - not syncing: No working init found. Try passing init= option to kernel. See Linux Documentation/init.txt for guidance.

Therefore always indicate presence of 2008-NaN support in R6 as well as in
R5+MSA CPUs, even though this feature is not yet supported by MIPS in QEMU.

Backports commit ba5c79f26221c0fd7139c883a34a4e75d993f732 from qemu
2018-02-22 11:30:08 -05:00
Denis V. Lunev eb29ff04ca
log: move qemu_log_close/qemu_log_flush from header to log.c
There is no particular reason to keep these functions in the header.
Suggested by Paolo.

Backports commit 99affd1d5bd4e396ecda50e53dfbc5147fa1313d from qemu
2018-02-22 11:13:17 -05:00
Yongbok Kim 6602163087
target-mips: add MAAR, MAARI register
The MAAR register is a read/write register included in Release 5
of the architecture that defines the accessibility attributes of
physical address regions. In particular, MAAR defines whether an
instruction fetch or data load can speculatively access a memory
region within the physical address bounds specified by MAAR.

As QEMU doesn't do speculative access, hence this patch only
provides ability to access the registers.

Backports commit f6d4dd810983fdf3d1c9fb81838167efef63d1c8 from qemu
2018-02-22 11:00:17 -05:00
Yongbok Kim 15e0109162
target-mips: use CP0_CHECK for gen_m{f|t}hc0
Reuse CP0_CHECK macro for gen_m{f|t}hc0.

Backports commit c98d3d79ee387ea6e8fb091299f8562b20022f10 from qemu
2018-02-22 10:49:55 -05:00
Leon Alrae 0c5ebbd096
target-mips: check CP0 enabled for CACHE instruction also in R6
Backports commit 40d48212f934d4deab40ffe84a0f9c4c553d4742 from qemu
2018-02-22 10:47:54 -05:00
Leon Alrae 70306ec586
target-mips: enable CM GCR in MIPS64R6-generic CPU
Indicate that in the MIPS64R6-generic CPU the memory-mapped
Global Configuration Register Space is implemented.

Backports commit a9a95061715ca09abff56a3f239f704c410912c2 from qemu
2018-02-22 10:46:40 -05:00
Yongbok Kim d65583df80
target-mips: add CMGCRBase register
Physical base address for the memory-mapped Coherency Manager Global
Configuration Register space.
The MIPS default location for the GCR_BASE address is 0x1FBF_8.
This register only exists if Config3 CMGCR is set to one.

Backports commit c870e3f52cac0c8a4a1377398327c4ff20d49d41 from qemu
2018-02-22 10:43:26 -05:00
Paolo Bonzini 1435732c0d
target-i386: implement PKE for TCG
Backports commit 0f70ed4759a29ca932af1e9525729f4f455642f8 from qemu
2018-02-22 10:18:55 -05:00
Dr. David Alan Gilbert 58fcb2b57b
config.status: Pass extra parameters
This allows you to do:
./config.status --the-option-you-forgot

Backports commit cf7cc9291bf7f2f6470815db876ed28eb474ea52 from qemu
2018-02-22 10:12:54 -05:00
Alex Bennée d01c318b3e
cputlb: modernise the debug support
To avoid cluttering the code with #ifdef legs we wrap up the print
statements into a tlb_debug() macro. As access to the virtual TLB can
get quite heavy defining DEBUG_TLB_LOG will ensure all the logs go to
the qemu_log target of CPU_LOG_MMU instead of stderr. This remains
compile time optional as these debug statements haven't been considered
for usefulness for user visible logging.

I've also removed DEBUG_TLB_CHECK which wasn't used.

Backports commit 8526e1f4e418443a4d6ed0714487e47d45ef9c98 from qemu
2018-02-22 10:10:45 -05:00
Alex Bennée 3da7d9d9ae
qemu-log: dfilter-ise exec, out_asm, op and opt_op
qemu-log: dfilter-ise exec, out_asm, op and opt_op

This ensures the code generation debug code will honour -dfilter if set.
For the "exec" tracing I've added a new inline macro for efficiency's
sake.

Backports commit d977e1c2dbc9e63454b2000f91954d02543bf43b from qemu
2018-02-22 10:06:19 -05:00
Alex Bennée 2d401b6f23
qemu-log: new option -dfilter to limit output
When debugging big programs or system emulation sometimes you want both
the verbosity of cpu,exec et all but don't want to generate lots of logs
for unneeded stuff. This patch adds a new option -dfilter which allows
you to specify interesting address ranges in the form:

-dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,...

Then logging code can use the new qemu_log_in_addr_range() function to
decide if it will output logging information for the given range.

Backports commit 3514552e04388d8e7686bcf89efd022e892acb5b from qemu
2018-02-22 10:02:26 -05:00
Lioncash b895ae38a9
fpu: silence warnings 2018-02-22 09:52:28 -05:00
Peter Maydell 3f5e36e15f
qemu-log: Improve the exec TB execution logging
Improve the TB execution logging so that it is easier to identify
what is happening from trace logs:
* move the "Trace" logging of executed TBs into cpu_tb_exec()
so that it is emitted if and only if we actually execute a TB,
and for consistency for the CPU state logging
* log when we link two TBs together via tb_add_jump()
* log when cpu_tb_exec() returns early from a chain of TBs

The new style logging looks like this:

Trace 0x7fb7cc822ca0 [ffffffc0000dce00]
Linking TBs 0x7fb7cc822ca0 [ffffffc0000dce00] index 0 -> 0x7fb7cc823110 [ffffffc0000dce10]
Trace 0x7fb7cc823110 [ffffffc0000dce10]
Trace 0x7fb7cc823420 [ffffffc000302688]
Trace 0x7fb7cc8234a0 [ffffffc000302698]
Trace 0x7fb7cc823520 [ffffffc0003026a4]
Trace 0x7fb7cc823560 [ffffffc0000dce44]
Linking TBs 0x7fb7cc823560 [ffffffc0000dce44] index 1 -> 0x7fb7cc8235d0 [ffffffc0000dce70]
Trace 0x7fb7cc8235d0 [ffffffc0000dce70]
Stopped execution of TB chain before 0x7fb7cc8235d0 [ffffffc0000dce70]
Trace 0x7fb7cc8235d0 [ffffffc0000dce70]
Trace 0x7fb7cc822fd0 [ffffffc0000dd52c]

Backports commit 1a830635229e14c403600167823ea6b3b79d3097 from qemu
2018-02-22 09:40:11 -05:00
Peter Maydell 66e1bacd64
qemu-log: Avoid function call for disabled qemu_log_mask logging
Make qemu_log_mask() a macro which only calls the function to
do the actual work if the logging is enabled. This avoids making
a function call in possible fast paths where logging is disabled.

Backports commit 7ee606230e6b7645d92365d9b39179368e83ac54 from qemu
2018-02-22 09:32:48 -05:00
Alex Bennée bc5d7c5e1d
tcg: pass down TranslationBlock to tcg_code_gen
My later debugging patches need access to the origin PC which is held in
the TranslationBlock structure. Pass down the whole structure as it also
holds the information about the code start point.

Backports commit 5bd2ec3d7b47b2252745882795d79aef36380fb7 from qemu
2018-02-22 09:28:06 -05:00
Veronia Bahaa bafc81b1d3
util: move declarations out of qemu-common.h
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)

Backports commit f348b6d1a53e5271cf1c9f9acc4646b4b98c1771 from qemu
2018-02-22 09:25:48 -05:00
Marc-André Lureau fff79ed49b
utils: rename strtosz to use qemu prefix
Not only it makes sense, but it gets rid of checkpatch warning:
WARNING: consider using qemu_strtosz in preference to strtosz

Also remove get rid of tabs to please checkpatch.

Backports commit 4677bb40f809394bef5fa07329dea855c0371697 from qemu
2018-02-22 00:17:52 -05:00
Rutuja Shah d9fdc180d7
Replaced get_tick_per_sec() by NANOSECONDS_PER_SECOND
This patch replaces get_ticks_per_sec() calls with the macro
NANOSECONDS_PER_SECOND. Also, as there are no callers, get_ticks_per_sec()
is then removed. This replacement improves the readability and
understandability of code.

For example,

timer_mod(fdctrl->result_timer,
qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + (get_ticks_per_sec() / 50));

NANOSECONDS_PER_SECOND makes it obvious that qemu_clock_get_ns
matches the unit of the expression on the right side of the plus.

Backports commit 73bcb24d932912f8e75e1d88da0fc0ac6d4bce78 from qemu
2018-02-21 23:21:36 -05:00
Paolo Bonzini c024ca9f49
hw: explicitly include qemu-common.h and cpu.h 2018-02-21 23:15:09 -05:00
Markus Armbruster 6730bd3131
Move QEMU_ALIGN_*() from qemu-common.h to qemu/osdep.h
qemu-common.h should only be included by .c files. Its file comment
explains why: "No header file should depend on qemu-common.h, as this
would easily lead to circular header dependencies."

One of the reasons for headers to include it is QEMU_ALIGN_UP() and
QEMU_ALIGN_DOWN(). Move them next to ROUND_UP() in qemu/osdep.h, to
facilitate removing these ill-advised includes later on.

Backports commit e07e540aaa08718c9ff8213067a3dcef31b3e313 from qemu
2018-02-21 23:12:24 -05:00
Markus Armbruster 6b1ebd16e6
Move HOST_LONG_BITS from qemu-common.h to qemu/osdep.h
qemu-common.h should only be included by .c files. Its file comment
explains why: "No header file should depend on qemu-common.h, as this
would easily lead to circular header dependencies."

One of the reasons for headers to include it is HOST_LONG_BITS. Move
that to its more natural home qemu/osdep.h, to facilitate removing
these ill-advised includes later on.

This also lets us use HOST_LONG_BITS in bswap.h instead of duplicating
its definition there to avoid cyclic inclusion.

Backports commit a8139632161d7546218b696cada0a4f64cc78fb7 from qemu
2018-02-21 23:10:43 -05:00
Markus Armbruster 06668850e3
include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef. Since then, we've moved to include qemu/osdep.h
everywhere. Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h. That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h. Include qapi/error.h in .c files that need it and don't
get it now. Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly. Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h. Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third. Unfortunately, the number depending on
qapi-types.h shrinks only a little. More work is needed for that one.

Backports commit da34e65cb4025728566d6504a99916f6e7e1dd6a from qemu
2018-02-21 23:08:18 -05:00
Stefan Weil baa477d324
Remove unneeded include statements for setjmp.h
As soon as setjmp.h is included from qemu/osdep.h, those old include
statements are no longer needed.

Add also setjmp.h to the list in scripts/clean-includes.

Backports commit 8ff98f1ed2f50cd05c3c5027c7efdf69859ec664 from qemu
2018-02-21 22:57:32 -05:00
Stefan Weil 904b3c467e
Include setjmp.h in qemu/osdep.h (bug fix for w64)
setjmp must be declared before sysemu/os-win32.h
because it is redefined there for 64 bit Windows.

Backports commit e89fdafb58038038e3ccb860c5e1068ba063bac8 from qemu
2018-02-21 22:56:46 -05:00
Eric Blake 2f30651c40
qapi: Use anonymous bases in QMP flat unions
Now that the generator supports it, we might as well use an
anonymous base rather than breaking out a single-use Base
structure, for all three of our current QMP flat unions.

Oddly enough, this change does not affect the resulting
introspection output (because we already inline the members of
a base type into an object, and had no independent use of the
base type reachable from a command).

The case_whitelist now has to list the name of an implicit
type; which is not too bad (consider it a feature if it makes
it harder for developers to make the whitelist grow :)

Backports commit 3666a97f78704b941c360dc917acb14c8774eca7 from qemu
2018-02-21 22:55:12 -05:00
Eric Blake e16b731799
qapi: Allow anonymous base for flat union
Rather than requiring all flat unions to explicitly create
a separate base struct, we can allow the qapi schema to specify
the common members via an inline dictionary. This is similar to
how commands can specify an inline anonymous type for its 'data'.
We already have several struct types that only exist to serve as
a single flat union's base; the next commit will clean them up.
In particular, this patch's change to the BlockdevOptions example
in qapi-code-gen.txt will actually be done in the real QAPI schema.

Now that anonymous bases are legal, we need to rework the
flat-union-bad-base negative test (as previously written, it
forms what is now valid QAPI; tweak it to now provide coverage
of a new error message path), and add a positive test in
qapi-schema-test to use an anonymous base (making the integer
argument optional, for even more coverage).

Note that this patch only allows anonymous bases for flat unions;
simple unions are already enough syntactic sugar that we do not
want to burden them further. Meanwhile, while it would be easy
to also allow an anonymous base for structs, that would be quite
redundant, as the members can be put right into the struct
instead.

Backports commit ac4338f8eb783fd421aae492ca262a586918471e from qemu
2018-02-21 22:54:17 -05:00
Eric Blake 8f4a64398a
qapi: Don't special-case simple union wrappers
Simple unions were carrying a special case that hid their 'data'
QMP member from the resulting C struct, via the hack method
QAPISchemaObjectTypeVariant.simple_union_type(). But by using
the work we started by unboxing flat union and alternate
branches, coupled with the ability to visit the members of an
implicit type, we can now expose the simple union's implicit
type in qapi-types.h:

| struct q_obj_ImageInfoSpecificQCow2_wrapper {
| ImageInfoSpecificQCow2 *data;
| };
|
| struct q_obj_ImageInfoSpecificVmdk_wrapper {
| ImageInfoSpecificVmdk *data;
| };
...
| struct ImageInfoSpecific {
| ImageInfoSpecificKind type;
| union { /* union tag is @type */
| void *data;
|- ImageInfoSpecificQCow2 *qcow2;
|- ImageInfoSpecificVmdk *vmdk;
|+ q_obj_ImageInfoSpecificQCow2_wrapper qcow2;
|+ q_obj_ImageInfoSpecificVmdk_wrapper vmdk;
| } u;
| };

Doing this removes asymmetry between QAPI's QMP side and its
C side (both sides now expose 'data'), and means that the
treatment of a simple union as sugar for a flat union is now
equivalent in both languages (previously the two approaches used
a different layer of dereferencing, where the simple union could
be converted to a flat union with equivalent C layout but
different {} on the wire, or to an equivalent QMP wire form
but with different C representation). Using the implicit type
also lets us get rid of the simple_union_type() hack.

Of course, now all clients of simple unions have to adjust from
using su->u.member to using su->u.member.data; while this touches
a number of files in the tree, some earlier cleanup patches
helped minimize the change to the initialization of a temporary
variable rather than every single member access. The generated
qapi-visit.c code is also affected by the layout change:

|@@ -7393,10 +7393,10 @@ void visit_type_ImageInfoSpecific_member
| }
| switch (obj->type) {
| case IMAGE_INFO_SPECIFIC_KIND_QCOW2:
|- visit_type_ImageInfoSpecificQCow2(v, "data", &obj->u.qcow2, &err);
|+ visit_type_q_obj_ImageInfoSpecificQCow2_wrapper_members(v, &obj->u.qcow2, &err);
| break;
| case IMAGE_INFO_SPECIFIC_KIND_VMDK:
|- visit_type_ImageInfoSpecificVmdk(v, "data", &obj->u.vmdk, &err);
|+ visit_type_q_obj_ImageInfoSpecificVmdk_wrapper_members(v, &obj->u.vmdk, &err);
| break;
| default:
| abort();

Backports commit 32bafa8fdd098d52fbf1102d5a5e48d29398c0aa from qemu
2018-02-21 22:51:33 -05:00
Eric Blake 534e37585d
qapi: Drop unused c_null()
Now that we are always bulk-initializing a QAPI C struct to 0
(whether by g_malloc0() or by 'Type arg = {0};'), we no longer
have any clients of c_null() in the generator for per-element
initialization. This patch is easy enough to revert if we find
a use in the future, but in the present, get rid of the dead code.

Backports commit 861877a0dd0a8e1bdbcc9743530f4dc9745a736a from qemu
2018-02-21 22:49:33 -05:00
Eric Blake cd19e75fc2
qapi: Inline gen_visit_members() into lone caller
Commit 82ca8e46 noticed that we had multiple implementations of
visiting every member of a struct, and consolidated it into
gen_visit_fields() (now gen_visit_members()) with enough
parameters to cater to slight differences between the clients.
But recent exposure of implicit types has meant that we are now
down to a single use of that method, so we can clean up the
unused conditionals and just inline it into the remaining
caller: gen_visit_object_members().

Likewise, gen_err_check() no longer needs optional parameters,
as the lone use of non-defaults was via gen_visit_members().

No change to generated code.

Backports commit 12f254fd5f98717d17f079c73500123303b232da from qemu
2018-02-21 22:47:50 -05:00
Eric Blake a86b89f166
qapi-event: Utilize implicit struct visits
Rather than generate inline per-member visits, take advantage
of the 'visit_type_FOO_members()' function for emitting events.
This is possible now that implicit structs can be visited like
any other. Generated code shrinks accordingly; by initializing
a struct based on parameters, through a new gen_param_var()
helper, like:

|@@ -338,6 +250,9 @@ void qapi_event_send_block_job_error(con
| QMPEventFuncEmit emit = qmp_event_get_func_emit();
| QmpOutputVisitor *qov;
| Visitor *v;
|+ q_obj_BLOCK_JOB_ERROR_arg param = {
|+ (char *)device, operation, action
|+ };
|
| if (!emit) {
| return;
@@ -351,19 +266,7 @@ void qapi_event_send_block_job_error(con
| if (err) {
| goto out;
| }
|- visit_type_str(v, "device", (char **)&device, &err);
|- if (err) {
|- goto out_obj;
|- }
|- visit_type_IoOperationType(v, "operation", &operation, &err);
|- if (err) {
|- goto out_obj;
|- }
|- visit_type_BlockErrorAction(v, "action", &action, &err);
|- if (err) {
|- goto out_obj;
|- }
|-out_obj:
|+ visit_type_q_obj_BLOCK_JOB_ERROR_arg_members(v, &param, &err);
| visit_end_struct(v, err ? NULL : &err);

Notice that the initialization of 'param' has to cast away const
(just as the old gen_visit_members() had to do): we can't change
the signature of the user function (which uses 'const char *'), but
have to assign it to a non-const QAPI object (which requires
'char *').

While touching this, document with a FIXME comment that there is
still a potential collision between QMP members and our choice of
local variable names within qapi_event_send_FOO().

This patch also paves the way for some followup simplifications
in the generator, in subsequent patches.

Backports commit 0949e95b48e30715e157cabbc59dcb0ed912d3ff from qemu
2018-02-21 22:45:28 -05:00
Eric Blake eb4b02705a
qapi-event: Drop qmp_output_get_qobject() null check
qmp_output_get_qobject() was changed never to return null some time
ago (in commit 6c2f9a15), but the qapi_event_send_FOO() functions
still check. Clean that up:

|@@ -28,7 +28,6 @@ void qapi_event_send_acpi_device_ost(ACP
| QMPEventFuncEmit emit;
| QmpOutputVisitor *qov;
| Visitor *v;
|- QObject *obj;
|
| emit = qmp_event_get_func_emit();
| if (!emit) {
|@@ -54,10 +53,7 @@ out_obj:
| goto out;
| }
|
|- obj = qmp_output_get_qobject(qov);
|- g_assert(obj);
|-
|- qdict_put_obj(qmp, "data", obj);
|+ qdict_put_obj(qmp, "data", qmp_output_get_qobject(qov));
| emit(QAPI_EVENT_ACPI_DEVICE_OST, qmp, &err);
|
| out:

Backports commit 8df59565d2c27dec8c96a2090f0eb73303efce14 from qemu
2018-02-21 22:43:00 -05:00
Eric Blake 9aa8356bce
qapi: Adjust names of implicit types
The original choice of ':obj-' as the prefix for implicit types
made it obvious that we weren't going to clash with any user-defined
names, which cannot contain ':'. But now we want to create structs
for implicit types, to get rid of special cases in the generators,
and our use of ':' in implicit names needs a tweak to produce valid
C code.

We could transliterate ':' to '_', except that C99 mandates that
"identifiers that begin with an underscore are always reserved for
use as identifiers with file scope in both the ordinary and tag name
spaces". So it's time to change our naming convention: we can
instead use the 'q_' prefix that we reserved for ourselves back in
commit 9fb081e0. Technically, since we aren't planning on exposing
the empty type in generated code, we could keep the name ':empty',
but renaming it to 'q_empty' makes the check for startswith('q_')
cover all implicit types, whether or not code is generated for them.

As long as we don't declare 'empty' or 'obj' ticklish, it shouldn't
clash with c_name() prepending 'q_' to the user's ticklish names.

Backports commit 7599697c66d22ff4c859ba6ccea30e6a9aae6b9b from qemu
2018-02-21 22:41:38 -05:00
Eric Blake d777876e6b
qapi: Emit implicit structs in generated C
We already have several places that want to visit all the members
of an implicit object within a larger context (simple union variant,
event with anonymous data, command with anonymous arguments struct);
and will be adding another one soon (the ability to declare an
anonymous base for a flat union). Having a C struct declared for
these implicit types, along with a visit_type_FOO_members() helper
function, will make for fewer special cases in our generator.

We do not, however, need qapi_free_FOO() or visit_type_FOO()
functions for implicit types, because they should not be used
directly outside of the generated code. This is done by adding a
conditional in visit_object_type() for both qapi-types.py and
qapi-visit.py based on the object name. The comparison of
"name.startswith('q_')" is a bit hacky (it's basically duplicating
what .is_implicit() already uses), but beats changing the signature
of the visit_object_type() callback to pass a new 'implicit' flag.
The hack should be temporary: we are considering adding a future
patch that consolidates the narrow visit_object_type(..., base,
local_members, variants) and visit_object_type_flat(...,
all_members, variants) [where different sets of information are
already broken out, and the QAPISchemaObjectType is no longer
available] into a broader visit_object_type(obj_type) [where the
visitor can query the needed fields from obj_type directly].

Also, now that we WANT to output C code for implicits, we no longer
need the visit_needed() filter, leaving 'q_empty' as the only object
still needing a special case. Remember, 'q_empty' is the only
built-in generated object, which means that without a special case
it would be emitted in multiple files (the main qapi-types.h and in
qga-qapi-types.h) causing compilation failure due to redefinition.
But since it has no members, it's easier to just avoid an attempt to
visit that particular type; since gen_object() is called recursively,
we also prime the objects_seen set to cover any recursion into the
empty type.

The patch relies on the changed naming of implicit types in the
previous patch. It is a bit unfortunate that the generated struct
names and visit_type_FOO_members() don't match normal naming
conventions, but it's not too bad, since they will only be used in
generated code.

The generated code grows substantially in size: the implicit
'-wrapper' types must be emitted in qapi-types.h before any union
can include an unboxed member of that type. Arguably, the '-args'
types could be emitted in a private header for just qapi-visit.c
and qmp-marshal.c, rather than polluting qapi-types.h; but adding
complexity to the generator to split the output location according
to role doesn't seem worth the maintenance costs.

Backports commit 7ce106a96feee4d46bfcdb47127b0935804c9357 from qemu
2018-02-21 22:31:15 -05:00
Eric Blake f1a8fcd7a7
qapi: Drop useless 'data' member of unions
We started moving away from the use of the 'void *data' member
in the C union corresponding to a QAPI union back in commit
544a373; recent commits have gotten rid of other uses. Now
that it is completely unused, we can remove the member itself
as well as the FIXME comment. Update the testsuite to drop the
negative test union-clash-data.

Backports commit 48eb62a74fc2d6b0ae9e5f414304a85cfbf33066 from qemu
2018-02-21 22:27:26 -05:00
Lioncash 8728fea067
qapi-visit: Expose visit_type_FOO_members()
Dan Berrange reported a case where he needs to work with a
QCryptoBlockOptions union type using the OptsVisitor, but only
visit one of the branches of that type (the discriminator is not
visited directly, but learned externally). When things were
boxed, it was easy: just visit the variant directly, which took
care of both allocating the variant and visiting its members, then
store that pointer in the union type. But now that things are
unboxed, we need a way to visit the members without allocation,
done by exposing visit_type_FOO_members() to the user.

Before the patch, we had quite a bit of code associated with
object_members_seen to make sure that a declaration of the helper
was in scope before any use of the function. But now that the
helper is public and declared in the header, the .c file no
longer needs to worry about topological sorting (the helper is
always in scope), which leads to some nice cleanups.

Backports commit 4d91e9115cc6700113e772b19d1f39bbcf345977 from qemu
2018-02-21 22:26:38 -05:00
Eric Blake d28c6244c0
qapi: Rename 'fields' to 'members' in generated C code
C types and JSON objects don't have fields, but members. We
shouldn't gratuitously invent terminology. This patch is a
strict renaming of static genarated functions, plus the naming
of the dummy filler member for empty structs, before the next
patch exposes some of that naming to the rest of the code base.

Backports commit c81200b01422783cd29796ef4ccc275d05f9ce67 from qemu
2018-02-21 22:23:07 -05:00
Eric Blake 825fb4835b
qapi: Rename 'fields' to 'members' in generator
C types and JSON objects don't have fields, but members. We
shouldn't gratuitously invent terminology. This patch is a
strict renaming of generator code internals (including testsuite
comments), before later patches rename C interfaces.

No change to generated code with this patch.

Backports commit 14f00c6c492488381a513c3816b15794446231a0 from qemu
2018-02-21 22:20:02 -05:00
Eric Blake b239241e99
qapi: Make c_type() more OO-like
QAPISchemaType.c_type() is a bit awkward: it takes two optional
boolean flags is_param and is_unboxed, and they should never both
be True.

Add a new method for each of the flags, and drop the flags from
c_type().

Most callers pass no flags; they remain unchanged.

One caller passes is_param=True; call the new .c_param_type()
instead.

One caller passes is_unboxed=True, except for simple union types.
This is actually an ugly special case that will go away soon, so
until then, we now have to call either .c_type() or the new
.c_unboxed_type(). Tolerable in the interim.

It requires slightly more Python, but is arguably easier to read.

Backports commit 4040d995e49c5b818be79e50a18c1bf8d2354d12 from qemu
2018-02-21 22:01:09 -05:00
Eric Blake a7713451d9
qapi: Assert in places where variants are not handled
We are getting closer to the point where we could use one union
as the base or variant type within another union type (as long
as there are no collisions between any possible combination of
member names allowed across all discriminator choices). But
until we get to that point, it is worth asserting that variants
are not present in places where we are not prepared to handle
them: when exploding a type into a parameter list, we do not
expect variants. The qapi.py code is already checking this,
via the older check_type() method; but someday we hope to get
rid of that and move checking into QAPISchema*.check(). The
two asserts added here make sure any refactoring still catches
problems, and makes it locally obvious why we can iterate over
only type.members without worrying about type.variants.

Backports commit 29f6bd15eb8a55ed37b2a443f7275b3d134eb2b2 from qemu
2018-02-21 21:58:29 -05:00
Max Reitz 1cfdf802a9
qapi: Drop QERR_UNKNOWN_BLOCK_FORMAT_FEATURE
Just specifying a custom string is simpler in basically all places that
used it, and in addition, specifying the BB or node name is something we
generally do not do in other error messages when opening a BDS, so we
should not do it here.

This changes the output for iotest 036 (to the better, in my opinion),
so the reference output needs to be changed accordingly.

Backports commit a55448b3681a880b77eaefe8b2c42912000cb481 from qemu
2018-02-21 21:55:15 -05:00
Sergey Sorokin da6a9f331b
target-arm: Fix translation level on early translation faults
Qemu reports translation fault on 1st level instead of 0th level in case of
AArch64 address translation if the translation table walk is disabled or
the address is in the gap between the two regions.

Backports commit 1b4093ea6678ff79d3006db3d3abbf6990b4a59b from qemu
2018-02-21 21:53:15 -05:00
Peter Maydell 8309945dcc
target-arm: Implement MRS (banked) and MSR (banked) instructions
Starting with the ARMv7 Virtualization Extensions, the A32 and T32
instruction sets provide instructions "MSR (banked)" and "MRS
(banked)" which can be used to access registers for a mode other
than the current one:
* R<m>_<mode>
* ELR_hyp
* SPSR_<mode>

Implement the missing instructions.

Backports commit 8bfd0550be821cf27d71444e2af350de3c3d2ee3 from qemu
2018-02-21 21:50:42 -05:00
Daniel P. Berrange d561d28827
error: ensure errno detail is printed with error_abort
When &error_abort is passed in, the error reporting code
will print the current error message and then abort() the
process. Unfortunately at the time it aborts, we've not
yet appended the errno detail. This makes debugging certain
problems significantly harder as the log is incomplete.

Backports commit 20e2dec14954568848ad74e73aee9b3aeedd6584 from qemu
2018-02-21 21:40:24 -05:00
Paolo Bonzini 9cf056404a
exec: fix early return from ram_block_add
After reporting an error, ram_block_add was going on with the registration
of the RAMBlock. The visible effect is that it unlocked the ramlist
mutex twice.

Backports commit 39c350ee12e733070e63d64a21bd42607366ea99 from qemu
2018-02-21 21:37:58 -05:00
Richard Henderson 7775b05fb8
target-i386: Dump unknown opcodes with -d unimp
We discriminate here between opcodes that are illegal in the current
cpu mode or with illegal arguments (such as modrm.mod == 3) and
encodings that are unknown (such as an unimplemented isa extension).

Backports commit b9f9c5b41aab06479cb1695990b7cca98ef84fc7 from qemu
2018-02-21 21:37:16 -05:00
Richard Henderson 1c096b8fa2
target-i386: Fix inhibit irq mask handling
The patch in 7f0b714 was too simplistic, in that we wound up setting
the flag and then resetting it immediately in gen_eob.

Fixes the reported boot problem with Windows XP.

Backports commit f083d92c03e7a0741d2a9eba774a60d5a3ca772f from qemu
2018-02-21 21:24:50 -05:00
Richard Henderson c7d5d85979
target-i386: Use gen_nop_modrm for prefetch instructions
Backports commit 26317698ef3be5942c5ee5630997dbc98431c5f6 from qemu
2018-02-21 21:22:52 -05:00
Paolo Bonzini 55c2a21fe8
target-i386: Fix addr16 prefix
While ADDSEG will only be false in 16-bit mode for LEA, it can be
false even in other cases when 16-bit addresses are obtained via
the 67h prefix in 32-bit mode. In this case, gen_lea_v_seg forgets
to add a nonzero FS or GS base if CS/DS/ES/SS are all zero. This
case is pretty rare but happens when booting Windows 95/98, and
this patch fixes it.

The bug is visible since commit d6a291498, but it was introduced
together with gen_lea_v_seg and it probably could be reproduced
with a "addr16 gs movsb" instruction as early as in commit
ca2f29f555805d07fb0b9ebfbbfc4e3656530977.

Backports commit e2e02a820741ec4d96b8f313b06a2a7ed5e94fbd from qemu
2018-02-21 21:21:26 -05:00
Richard Henderson 085a3c9aab
target-i386: Fix SMSW for 64-bit mode
In non-64-bit modes, the instruction always stores 16 bits.
But in 64-bit mode, when the destination is a register, the
instruction can write 32 or 64 bits.

Backports commit a657f79e32422634415c09f3f15c73d610297af5 from qemu
2018-02-21 21:19:33 -05:00
Paolo Bonzini a233d7b13e
target-i386: Fix SMSW and LMSW from/to register
SMSW and LMSW accept register operands, but commit 1906b2a ("target-i386:
Rearrange processing of 0F 01", 2016-02-13) did not account for that.

Backports commit 880f8486503b32a29b653a3c0b3cfc5432012f38 from qemu
2018-02-21 21:17:45 -05:00
Paolo Bonzini bdf1189046
target-i386: Avoid repeated calls to the bnd_jmp helper
Two flags were tested the wrong way.

Backports commit 8b33e82b863d1c6fce7e69a41f6c96a8e15b73fb from qemu
2018-02-21 21:13:37 -05:00
Fam Zheng f7bff04b7b
exec: Introduce AddressSpaceDispatch.mru_section
Under heavy workloads the lookup will likely end up with the same
MemoryRegionSection from last time. Using a pointer to cache the result,
like ram_list.mru_block, significantly reduces cost of
address_space_translate.

During address space topology update, as->dispatch will be reallocated
so the pointer is invalidated automatically.

Perf reports a visible drop on the cpu usage, because phys_page_find is
not called. Before:

2.35% qemu-system-x86_64 [.] phys_page_find
0.97% qemu-system-x86_64 [.] address_space_translate_internal
0.95% qemu-system-x86_64 [.] address_space_translate
0.55% qemu-system-x86_64 [.] address_space_lookup_region

After:

0.97% qemu-system-x86_64 [.] address_space_translate_internal
0.97% qemu-system-x86_64 [.] address_space_lookup_region
0.84% qemu-system-x86_64 [.] address_space_translate

Backports commit 729633c2bc30496073431584eb6e304776b4ebd4 from qemu
2018-02-21 21:10:16 -05:00
Fam Zheng f642465dc4
exec: Factor out section_covers_addr
This will be shared by the next patch.

Also add a comment explaining the unobvious condition on "size.hi".

Backports commit 29cb533d8cbff1330717619780c2f1dfe764e003 from qemu
2018-02-21 21:08:08 -05:00
Daniel P. Berrange eddfb13c2c
qom: Change object property iterator API contract
Currently the ObjectProperty iterator API works as follows:

ObjectPropertyIterator *iter;

iter = object_property_iter_init(obj);
while ((prop = object_property_iter_next(iter))) {
...
}
object_property_iter_free(iter);

This has the benefit that the ObjectPropertyIterator struct
can be opaque, but has the downside that callers need to
explicitly call a free function. It is also not in keeping
with iterator style used elsewhere in QEMU/GLib2.

This patch changes the API to use stack allocation instead:

ObjectPropertyIterator iter;

object_property_iter_init(&iter, obj);
while ((prop = object_property_iter_next(&iter))) {
...
}

Backports commit 7746abd8e9ee9db20c0b0fdb19504f163ba3cbea from qemu
2018-02-21 21:03:58 -05:00
Daniel P. Berrange b97ab59f08
qom: Allow properties to be registered against classes
When there are many instances of a given class, registering
properties against the instance is wasteful of resources. The
majority of objects have a statically defined list of possible
properties, so most of the properties are easily registerable
against the class. Only those properties which are conditionally
registered at runtime need be recorded against the klass.

Registering properties against classes also makes it possible
to provide static introspection of QOM - currently introspection
is only possible after creating an instance of a class, which
severely limits its usefulness.

This impl only supports simple scalar properties. It does not
attempt to allow child object / link object properties against
the class. There are ways to support those too, but it would
make this patch more complicated, so it is left as an exercise
for the future.

There is no equivalent to object_property_del() provided, since
classes must be immutable once they are defined.

Backports commit 16bf7f522a2ff68993f80631ed86254c71eaf5d4 from qemu
2018-02-21 21:00:56 -05:00
Pavel Fedin 825bc2fb04
qom: Replace object property list with GHashTable
ARM GICv3 systems with large number of CPUs create lots of IRQ pins. Since
every pin is represented as a property, number of these properties becomes
very large. Every property add first makes sure there's no duplicates.
Traversing the list becomes very slow, therefore QEMU initialization takes
significant time (several seconds for e. g. 16 CPUs).

This patch replaces list with GHashTable, making lookup very fast. The only
drawback is that object_child_foreach() and object_child_foreach_recursive()
cannot add or remove properties during traversal, since GHashTableIter does
not have modify-safe version. However, the code seems not to modify objects
via these functions.

Backports commit b604a854e843505007c59d68112c654556102a20 from qemu
2018-02-21 13:35:10 -05:00
Lioncash 4b79ff71b4
glib_compat: backport hashtable iterator interfaces 2018-02-21 13:18:44 -05:00
Markus Armbruster 9bc51db79d
memory: Fix bad error handling in memory_region_init_ram_ptr()
Commit ef701d7 screwed up handling of out-of-memory conditions.
Before the commit, we report the error and exit(1), in one place.  The
commit lifts the error handling up the call chain some, to three
places.  Fine.  Except it uses &error_abort in these places, changing
the behavior from exit(1) to abort(), and thus undoing the work of
commit 3922825 "exec: Don't abort when we can't allocate guest
memory".

The previous two commits fixed one of the three places, another one
was fixed in commit 33e0eb5.  This commit fixes the third one.

Backports commit 0bdaa3a429c6d07cd437b442a1f15f70be1addaa from qemu
2018-02-21 11:24:38 -05:00
Pavel Fedin 0201c71145
Merge memory_region_init_reservation() into memory_region_init_io()
Just specifying ops = NULL in some cases can be more convenient than having
two functions.

Backports commit 6d6d2abf2c2e52c0f404d0a31a963e945b0cc7ad from qemu
2018-02-21 11:23:00 -05:00
Paolo Bonzini 7a1ce36785
memory: fix refcount leak in memory_region_present
memory_region_present() leaks a reference to a MemoryRegion in the
case "mr == container".  While fixing it, avoid reference counting
altogether for memory_region_present(), by using RCU only.

The return value could in principle be already invalid immediately
after memory_region_present returns, but presumably the caller knows
that and it's using memory_region_present to probe for devices that
are unpluggable, or something like that.  The RCU critical section
is needed anyway, because it protects as->current_map.

Backports commit c6742b14fe7352059cd4954a356a8105757af31b from qemu
2018-02-21 11:17:19 -05:00
Paolo Bonzini f9315cde1c
memory: do not add a reference to the owner of aliased regions
Very often the owner of the aliased region is the same as the owner of the alias
region itself.  When this happens, the reference count can never go back to 0 and
the owner is leaked.  This is for example breaking hot-unplug of virtio-pci
devices (the device cannot be plugged back again with the same id).

Another common use for alias is to transform the system I/O address space
into an MMIO regions; in this case the aliased region never dies, so there
is no problem.  Otherwise the owner is always the same for aliasing
and aliased region.

I checked all calls to memory_region_init_alias introduced after commit
dfde4e6 (memory: add ref/unref calls, 2013-05-06) and they do not need the
reference in order to keep the owner of the aliased region alive.

Backports commit 52c91dac6bd891656f297dab76da51fc8bc61309 from qemu
2018-02-21 11:10:49 -05:00
Lioncash 10bf76861b
exec: Remove unnecessary return in qemu_ram_remap 2018-02-21 09:51:23 -05:00
Fam Zheng fa7d3e6cdb
memory: Drop MemoryRegion.ram_addr
All references to mr->ram_addr are replaced by
memory_region_get_ram_addr(mr) (except for a few assertions that are
replaced with mr->ram_block).

Backports commit 8e41fb63c5bf29ecabe0cee1239bf6230f19978a from qemu
2018-02-21 08:53:08 -05:00
Fam Zheng 2c1a72635d
memory: Implement memory_region_get_ram_addr with mr->ram_block
Backports commit 7ebb2745acbb8d910eab07dc5f0aa01a4457703c from qemu
2018-02-21 08:53:08 -05:00
Fam Zheng 4b8c428494
memory: Move assignment to ram_block to memory_region_init_*
We don't force "const" qualifiers with pointers in QEMU, but it's still
good to keep a clean function interface. Assigning to mr->ram_block is
in this sense ugly - one initializer mutating its owning object's state.

Move it to memory_region_init_*, where mr->ram_addr is assigned.

Backports commit 0a75601853c00f3729fa62c49ec0d4bb1e3d9bc1 from qemu
2018-02-21 08:53:08 -05:00
Gonglei aa80edbef0
exec: Return RAMBlock pointer from allocating functions
Previously we return RAMBlock.offset; now return the pointer to the
whole structure.

ram_block_add returns void now, error is completely passed with errp.

Backports commit 528f46af6ecd1e300db18684969104d4067b867b from qemu
2018-02-21 08:52:57 -05:00
Ralf-Philipp Weinmann 893b9f7f96
target-arm: Only trap SRS from S-EL1 if specified mode is MON
Commit cbc0326b6fb9 caused SRS instructions executed from Secure
EL1 to trap to EL3 even if the specified mode was not monitor mode.

According to the ARMv8 Architecture reference manual [F6.1.203], ALL
of the following conditions need to be met for SRS to trap to EL3:
* It is executed at Secure PL1.
* The specified mode is monitor mode.
* EL3 is using AArch64.

Correct the condition governing the trap to EL3 to check the
specified mode.

Backports commit ba63cf47a93041137a94e86b7d0cd87fc896949b from qemu
2018-02-21 02:49:28 -05:00
Paolo Bonzini 7f23f7004d
target-arm: implement BE32 mode in system emulation
System emulation only has a little-endian target; BE32 mode
is implemented by adjusting the low bits of the address
for every byte and halfword load and store. 64-bit accesses
flip the low and high words.

Backports commit e334bd3190f6c4ca12f1d40d316dc471c70009ab from qemu
2018-02-21 02:47:22 -05:00
Paolo Bonzini aa5be4d6ca
target-arm: implement setend
Since this is not a high-performance path, just use a helper to
flip the E bit and force a lookup in the hash table since the
flags have changed.

Backports commit 9886ecdf31165de2d4b8bccc1a220bd6ac8bc192 from qemu
2018-02-21 02:39:13 -05:00
Peter Crosthwaite 902170741a
target-arm: introduce tbflag for endianness
Introduce a tbflags for endianness, set based upon the CPUs current
endianness. This in turn propagates through to the disas endianness
flag.

Backports commit 91cca2cda9823b1e7a049cb308a05104b5076cba from qemu
2018-02-21 02:35:34 -05:00
Peter Crosthwaite 50a3c7f2ee
target-arm: a64: Add endianness support
Set the dc->mo_endianness flag for AA64 and use it in all ldst ops.

Backports commit aa6489da4e297fb3ffcbc09b50afd700395b6386 from qemu
2018-02-21 02:31:50 -05:00
Paolo Bonzini 9ab3d105fd
target-arm: introduce disas flag for endianness
Introduce a disas flag for setting the CPU data endianness. This allows
control of the endianness from the CPU state rather than hard-coding it
to TARGET_WORDS_BIGENDIAN.

Backports commit dacf0a2ff7d39ab12bd90f2f5496a3889facd54a from qemu
2018-02-21 02:20:50 -05:00
Peter Crosthwaite e5cfcc3221
target-arm: implement SCTLR.EE
Implement SCTLR.EE bit which controls data endianess for exceptions
and page table translations. SCTLR.EE is mirrored to the CPSR.E bit
on exception entry.

Backports commit 73462dddf670c32c45c8ea359658092b0365b2d4 from qemu
2018-02-21 02:14:56 -05:00
Peter Crosthwaite 38f4a833a4
arm: cpu: handle BE32 user-mode as BE
endian with address manipulations on subword accesses (to give the
illusion of BE). But user-mode cannot tell the difference and is
already implemented as straight BE. So handle the difference in the
endianess query, where USER mode is BE and system is not.

Backports commit b2e62d9a7b9a2eb10e451a57813bad168376e122 from qemu
2018-02-21 02:12:39 -05:00
Peter Crosthwaite 1457b73a13
target-arm: cpu: Move cpu_is_big_endian to header
There is a CPU data endianness test that is used to drive the
virtio_big_endian test.

Move this up to the header so it can be more generally used for endian
tests. The KVM specific cpu_syncronize_state call is left behind in the
virtio specific function.

Rename it arm_cpu-data_is_big_endian() to more accurately capture that
this is for data accesses only.

Backports commit ed50ff7875d61a75517c92deb0444d73fbbca878 from qemu
2018-02-21 02:10:48 -05:00
Paolo Bonzini ec15ee10d0
target-arm: implement SCTLR.B, drop bswap_code
bswap_code is a CPU property of sorts ("is the iside endianness the
opposite way round to TARGET_WORDS_BIGENDIAN?") but it is not the
actual CPU state involved here which is SCTLR.B (set for BE32
binaries, clear for BE8).

Replace bswap_code with SCTLR.B, and pass that to arm_ld*_code.
The next patches will make data fetches honor both SCTLR.B and
CPSR.E appropriately.

Backports commit f9fd40ebe4f55e0048e002925b8d65e66d56e7a7 from qemu
2018-02-21 02:08:05 -05:00
Peter Maydell 64a9bec68a
target-arm: Correct handling of writes to CPSR mode bits from gdb in usermode
In helper.c the expression
(env->uncached_cpsr & CPSR_M) != CPSR_USER
is always true; the right hand side was supposed to be ARM_CPU_MODE_USR
(an error in commit cb01d391).

Since the incorrect expression was always true, this just meant that
commit cb01d391 had no effect.

However simply changing the RHS here would reveal a logic error: if
the mode is USR we wish to completely ignore the attempt to set the
mode bits, which means that we must clear the CPSR_M bits from mask
to avoid the uncached_cpsr bits being updated at the end of the
function.

Move the condition into the correct place in the code, fix its RHS
constant, and add a comment about the fact that we must be doing a
gdbstub write if we're in user mode.

Backports commit 8c4f0eb94cc65ee32a12feba88d0b32e3665d5ea from qemu
2018-02-21 01:57:34 -05:00
Lluís Vilanova d111e2df2d
typedefs: Add CPUState
Backports commit b23197f9cf2f221a6cc6272d36852f4f70cf9c1b from qemu
2018-02-21 01:55:22 -05:00
Lioncash 1c04024688
tcg: Make cpu_regs_sparc a TCGv array 2018-02-21 01:50:28 -05:00
Lioncash db114261e3
target-sparc: Cleanup casts and unnessecary alloc/dealloc 2018-02-21 01:44:51 -05:00
Lioncash c0210ac8a6
tcg: Make cpu_wim a TCGv 2018-02-21 01:41:53 -05:00
Lioncash 58c5a28893
tcg: Make cpu_ver a TCGv 2018-02-21 01:40:30 -05:00
Lioncash 2beea0db0d
tcg: Make cpu_ssr a TCGv 2018-02-21 01:39:15 -05:00
Lioncash b09a8626f0
tcg: Make cpu_hver a TCGv 2018-02-21 01:38:07 -05:00
Lioncash e161e9dcb4
tcg: Make cpu_htba a TCGv 2018-02-21 01:35:40 -05:00
Lioncash 577386b246
tcg: Make cpu_hintp a TCGv 2018-02-21 01:34:13 -05:00
Lioncash 2df9744bdb
tcg: Make cpu_stick_cmpr and cpu_hstick_cmpr TCGv 2018-02-21 01:32:59 -05:00
Lioncash 2d9d8c5e01
tcg: Make cpu_tick_cmpr a TCGv 2018-02-21 01:30:00 -05:00
Lioncash e5401deb09
tcg: Make cpu_npc a TCGv 2018-02-21 01:25:40 -05:00
Lioncash 6ccd4479d7
tcg: Make sparc_cpu_pc a TCGv 2018-02-21 01:23:58 -05:00
Lioncash e5a776b495
tcg: Make cpu_fsr a TCGv 2018-02-21 01:22:16 -05:00
Lioncash b51f920404
tcg: Make cpu_gsr a TCGv
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4
allows making the type concrete. Also fixes a leak with sparc
2018-02-21 01:17:01 -05:00
Lioncash 4da2fd6407
tcg: Make cpu_cond a TCGv
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4
allows making the type concrete
2018-02-21 01:12:15 -05:00
Lioncash 2f785b11d2
tcg: Make cpu_tbr a TCGv
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4
allows making the type concrete
2018-02-21 01:12:11 -05:00
Lioncash bbc8517cd2
tcg: Make cpu_y a TCGv
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4
allows making the type concrete
2018-02-21 01:06:36 -05:00
Lioncash a913b3e468
tcg: Make cpu_gpr a TCGv array
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4
allows making the type concrete
2018-02-21 01:02:46 -05:00
Lioncash 1defc70341
tcg: Make cpu_PC a TCGv
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4
allows making the type concrete
2018-02-21 00:47:13 -05:00
Lioncash 372e3307c5
tcg: Make bcond, btarget and cpu_dspctrl TCGv
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4
allows making the type concrete
2018-02-21 00:45:59 -05:00
Lioncash baf25644dd
tcg: Make cpu_HI and cpu_LO a TCGv array
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4
allows making the type concrete
2018-02-21 00:34:49 -05:00
Lioncash 50b871f523
tcg: Make store_dummy a TCGv
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4
allows making the type concrete
2018-02-21 00:24:40 -05:00
Lioncash 53f66f4762
tcg: Make QREG member variables TCGv instances
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4
allows making the type concrete
2018-02-21 00:23:22 -05:00
Lioncash 04b743a26c
tcg: Make cpu_dreg and cpu_areg TCGv arrays
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4
allows making the type concrete.
2018-02-21 00:23:17 -05:00
Lioncash 6b19f43925
tcg: Make cpu_tmp1 and cpu_tmp4 a TCGv
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4 allows
making the type concrete.
2018-02-21 00:07:23 -05:00
Lioncash 7caca36070
tcg: Make cpu_cc_dst, cpu_cc_src, cpu_cc_src2, and cpu_cc_srcT a TCGv
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4 allows us to make the types concrete
2018-02-21 00:00:08 -05:00
Lioncash 4062dcc9bc
tcg: Make cpu_T0 and cpu_T1 TCGv
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4 allows us
to make the type concrete
2018-02-20 23:51:44 -05:00
Lioncash 72170ae5c0
tcg: Make cpu_A0 a TCGv
Commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4 allows us to make the type concrete.
2018-02-20 23:43:58 -05:00
Lioncash ccbf1ed6ed
tcg: Make cpu_regs a TCGv array
Commit eae07f4767 allows us
to make the type concrete as opposed to using void* and malloc
2018-02-20 23:41:21 -05:00
Lioncash 02b2d3c873
tcg: Make cpu_seg_base a TCGv array
Commit eae07f4767 allows us to
use the type directly instead of casting to void and using malloc
(yay).
2018-02-20 23:34:38 -05:00
Lluís Vilanova eae07f4767
tcg: Move definition of type TCGv
The target-dependant type TCGv must be defined in "tcg/tcg.h" before
including the tracing helper wrappers in "tcg/tcg-op.h".

It also makes more sense to define it here, where other TCG types are
defined too.

Backports commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4 from qemu
2018-02-20 23:09:12 -05:00
Lluís Vilanova 7db1bffdee
tcg: Add type for vCPU pointers
Adds the 'TCGv_env' type for pointers to 'CPUArchState' objects. The
tracing infrastructure later needs to differentiate between regular
pointers and pointers to vCPUs.

Also changes all targets to use the new 'TCGv_env' type instead of the
generic 'TCGv_ptr'. As of now, the change is merely cosmetic ('TCGv_env'
translates into 'TCGv_ptr'), but that could change in the future to
enforce the difference.

Note that a 'TCGv_env' type (for 'CPUState') is not added, since all
helpers currently receive the architecture-specific
pointer ('CPUArchState').

Backports commit 1bcea73e13b2b059d0cb3301aeaca43e5656ef57 from qemu
2018-02-20 22:53:58 -05:00
Peter Maydell 20712bcb9a
target-arm: Make reserved ranges in ID_AA64* spaces RAZ, not UNDEF
The v8 ARM ARM defines that unused spaces in the ID_AA64* system
register ranges are Reserved and must RAZ, rather than being UNDEF.
Implement this.

In particular, ARM v8.2 adds a new feature register ID_AA64MMFR2,
and newer versions of the Linux kernel will attempt to read this,
which causes them not to boot up on versions of QEMU missing this fix.

Since the encoding .opc0 = 3, .opc1 = 0, .crn = 0, .crm = 2, .opc2 = 6
is actually defined in ARMv8 (as ID_MMFR4), we give it an entry in
the ARMCPU struct so CPUs can override it, though since none do
this too will just RAZ.

Backports commit e20d84c1407d43d5a2e2ac95dbb46db3b0af8f9f from qemu
2018-02-20 22:49:43 -05:00
Edgar E. Iglesias 66c4bd02eb
target-arm: Mark CNTHP_TVAL_EL2 as ARM_CP_NO_RAW
Mark CNTHP_TVAL_EL2 as ARM_CP_NO_RAW due to the register not
having any underlying state. This fixes an issue with booting
KVM enabled kernels when EL2 is on.

Backports commit d44ec156300a149b386a14d3ab349d3b83b66b8c from qemu
2018-02-20 22:30:44 -05:00
Peter Maydell eb02f0e818
target-arm: Implement MDCR_EL3.TPM and MDCR_EL2.TPM traps
Implement the performance monitor register traps controlled
by MDCR_EL3.TPM and MDCR_EL2.TPM. Most of the performance
registers already have an access function to deal with the
user-enable bit, and the TPM checks can be added there. We
also need a new access function which only implements the
TPM checks for use by the few not-EL0-accessible registers
and by PMUSERENR_EL0 (which is always EL0-readable).

Backports commit 1fce1ba985d9c5c96e5b9709e1356d1814b8fa9e from qemu
2018-02-20 22:29:26 -05:00
Peter Maydell ece364e7cc
target-arm: Fix handling of SDCR for 32-bit code
Fix two issues with our implementation of the SDCR:
* it is only present from ARMv8 onwards
* it does not contain several of the trap bits present in its 64-bit
counterpart the MDCR_EL3

Put the register description in the right place so that it does not
get enabled for ARMv7 and earlier, and give it a write function so that
we can mask out the bits which should not be allowed to have an effect
if EL3 is 32-bit.

Backports commit a8d64e735182cbbb5dcc98f41656b118c45e57cc from qemu
2018-02-20 22:26:58 -05:00
Peter Maydell 8477ed6389
target-arm: Make Monitor->NS PL1 mode changes illegal if HCR.TGE is 1
If HCR.TGE is 1 then mode changes via CPS and MSR from Monitor to
NonSecure PL1 modes are illegal mode changes. Implement this check
in bad_mode_switch().

(We don't currently implement HCR.TGE, but this is the only missing
check from the v8 ARM ARM G1.9.3 and so it's worth adding now; the
rest of the HCR.TGE checks can be added later as necessary.)

Backports commit 10eacda787ac9990dc22d4437b289200c819712c from qemu
2018-02-20 22:24:19 -05:00
Peter Maydell 8bfdc63424
target-arm: Make mode switches from Hyp via CPS and MRS illegal
Mode switches from Hyp to any other mode via the CPS and MRS
instructions are illegal mode switches (though obviously switching
via exception return is valid). Add this check to bad_mode_switch().

Backports commit af393ffc6da116b9dd4c70901bad1f4cafb1773d from qemu
2018-02-20 22:23:23 -05:00
Peter Maydell 00d06bf20e
target-arm: In v8, make illegal AArch32 mode changes set PSTATE.IL
In v8, the illegal mode changes which are UNPREDICTABLE in v7 are
given architected behaviour:
* the mode field is unchanged
* PSTATE.IL is set (so any subsequent instructions will UNDEF)
* any other CPSR fields are written to as normal

This is pretty much the same behaviour we picked for our
UNPREDICTABLE handling, with the exception that for v8 we
need to set the IL bit.

Backports commit 81907a582901671c15be36a63b5063f88f3487e2 from qemu
2018-02-20 22:22:01 -05:00
Peter Maydell 2296fb5915
target-arm: Forbid mode switch to Mon from Secure EL1
In v8 trying to switch mode to Mon from Secure EL1 is an
illegal mode switch. (In v7 this is impossible as all secure
modes except User are at EL3.) We can handle this case by
making a switch to Mon valid only if the current EL is 3,
which then gives the correct answer whether EL3 is AArch32
or AArch64.

Backports commit 58ae2d1f037fae1d90eed4522053a85d79edfbec from qemu
2018-02-20 22:21:10 -05:00
Peter Maydell 4919c7287c
target-arm: Add Hyp mode checks to bad_mode_switch()
We don't actually support Hyp mode yet, but add the correct
checks for it to the bad_mode_switch() function for completeness.

Backports commit e6c8fc07b4fce0729bb747770756835f4b0ca7f4 from qemu
2018-02-20 22:20:19 -05:00
Peter Maydell 339e3e340e
target-arm: Add comment about not implementing NSACR.RFR
QEMU doesn't implement the NSACR.RFR bit, which is a permitted
IMPDEF in choice in ARMv7 and the only permitted choice in ARMv8.
Add a comment to bad_mode_switch() to note that this is why
FIQ is always a valid mode regardless of the CPU's Secure state.

Backports commit 52ff951b4f63a29593650a15efdf82f63d6d962d from qemu
2018-02-20 22:19:38 -05:00
Peter Maydell a468baff61
target-arm: In cpsr_write() ignore mode switches from User mode
The only case where we can attempt a cpsr_write() mode switch from
User is from the gdbstub; all other cases are handled in the
calling code (notably translate.c). Architecturally attempts to
alter the mode bits from user mode are simply ignored (and not
treated as a bad mode switch, which in v8 sets CPSR.IL). Make
mode switches from User ignored in cpsr_write() as well, for
consistency.

Backports commit cb01d3912c8b000ed26d5fe95f6c194b3e3ba7a6 from qemu
2018-02-20 22:18:48 -05:00
Peter Maydell 553e230088
target-arm: Raw CPSR writes should skip checks and bank switching
Raw CPSR writes should skip the architectural checks for whether
we're allowed to set the A or F bits and should also not do
the switching of register banks if the mode changes. Handle
this inside cpsr_write(), which allows us to drop the "manually
set the mode bits to avoid the bank switch" code from all the
callsites which are using CPSRWriteRaw.

This fixes a bug in 32-bit KVM handling where we had forgotten
the "manually set the mode bits" part and could thus potentially
trash the register state if the mode from the last exit to userspace
differed from the mode on this exit.

Backports commit f8c88bbcda76d5674e4bb125471371b41d330df8 from qemu
2018-02-20 22:17:48 -05:00
Peter Maydell 611d4dad4b
target-arm: Add write_type argument to cpsr_write()
Add an argument to cpsr_write() to indicate what kind of CPSR
write is being requested, since the exact behaviour should
differ for the different cases.

Backports commit 50866ba5a2cfe922aaf3edb79f6eac5b0653477a from qemu
2018-02-20 22:15:53 -05:00
Peter Maydell 6ae2357be6
target-arm: Give CPSR setting on 32-bit exception return its own helper
The rules for setting the CPSR on a 32-bit exception return are
subtly different from those for setting the CPSR via an instruction
like MSR or CPS. (In particular, in Hyp mode changing the mode bits
is not valid via MSR or CPS.) Split the exception-return case into
its own helper for setting CPSR, so we can eventually handle them
differently in the helper function.

Backports commit 235ea1f5c89abf30e452539b973b0dbe43d3fe2b from qemu
2018-02-20 22:08:35 -05:00
Yongbok Kim 46284f1a41
target-mips: implement R6 multi-threading
MIPS Release 6 provides multi-threading features which replace
pre-R6 MT Module. CP0.Config3.MT is always 0 in R6, instead there is new
CP0.Config5.VP (Virtual Processor) bit which indicates presence of
multi-threading support which includes CP0.GlobalNumber register and
DVP/EVP instructions.

Backports commit 01bc435b44b8802cc4697faa07d908684afbce4e from qemu
2018-02-20 22:02:40 -05:00
Paolo Bonzini abb0408274
target-i386: fix confusion in xcr0 bit position vs. mask
The xsave and xrstor helpers are accessing the x86_ext_save_areas array
using a bit mask instead of a bit position. Provide two sets of XSTATE_*
definitions and use XSTATE_*_BIT when a bit position is requested.

Backports commit cfc3b074de4b4ccee2540edbf8cfdb026dc19943 from qemu
2018-02-20 21:00:41 -05:00
Gonglei 26951bf754
memory: Remove unreachable return statement
Backports commit d61524486c6e503e502241a2ea834f930f98a6a1 from qemu
2018-02-20 20:54:24 -05:00
Gonglei d25285bc78
memory: optimize qemu_get_ram_ptr and qemu_ram_ptr_length
these two functions consume too much cpu overhead to
find the RAMBlock by ram address.

After this patch, we can pass the RAMBlock pointer
to them so that they don't need to find the RAMBlock
anymore most of the time. We can get better performance
in address translation processing.

Backports commit 3655cb9c7375a595a8051ec677c515b24d5c1fe6 from qemu
2018-02-20 20:53:31 -05:00
Gonglei 39e4d63e68
exec: store RAMBlock pointer into memory region
Each RAM memory region has a unique corresponding RAMBlock.
In the current realization, the memory region only stored
the ram_addr which means the offset of RAM address space,
We need to qurey the global ram.list to find the ram block
by ram_addr if we want to get the ram block, which is very
expensive.

Now, we store the RAMBlock pointer into memory region
structure. So, if we know the mr, we can easily get the
RAMBlock.

Backports commit 58eaa2174e99d9a05172d03fd2799ab8fd9e6f60 from qemu
2018-02-20 20:43:32 -05:00
Peter Maydell 764c2d09e5
tcg: Remove unnecessary osdep.h includes from tcg-target.inc.c
Commit 757e725b58c57d added a number of #include "qemu/osdep.h"
files to the tcg-target.c files (as they were named at the time).
These are unnecessary because these files are not standalone C
files, and the tcg/tcg.c file which includes them will have
already included osdep.h on their behalf. Remove the unneeded
include directives.

Backports commit c3b7f66800fbf9f47fddbcf2e2cd30ea932e0aae from qemu
2018-02-20 20:41:00 -05:00
Peter Maydell 7784a25470
tcg: Rename tcg-target.c to tcg-target.inc.c
Rename the per-architecture tcg-target.c files to tcg-target.inc.c.
This makes it clearer that they are not intended to be standalone
C files, but are instead #included into another source file.

Backports commit ce151109813e2770fd3cee2f37bfa2cdd01a12b9 from qemu
2018-02-20 20:39:57 -05:00
Richard Henderson d609ab30c2
target-sparc: Use global registers for the register window
Via indirection off cpu_regwptr.

Backports commit d2dc4069e046deeccc4dca0f73c3077ac22ba43f from qemu
2018-02-20 20:34:42 -05:00
Richard Henderson 3653771265
tcg: Allocate indirect_base temporaries in a different order
Since we've not got liveness analysis for indirect bases,
placing them at the end of the call-saved registers makes
it more likely that it'll stay live.

Backports commit 91478cefaaf2fa678e56df8635b34957f4d5d565 from qemu
2018-02-20 19:46:59 -05:00
Richard Henderson bf385eba3c
tcg: Implement indirect memory registers
That is, global_mem registers whose base is another global_mem
register, rather than a fixed register.

Backports commit b3915dbbdcdb2e04753f3d34a1b0865eea005069 from qemu
2018-02-20 19:20:01 -05:00
Richard Henderson 9299329349
tcg: Work around clang bug wrt enum ranges, part 2
A previous patch patch changed the type of REG from int
to enum TCGReg, which provokes the following bug in clang:

https://llvm.org/bugs/show_bug.cgi?id=16154

Backports commit 869938ae2a284fe730cb6f807ea0f9e324e0f87c from qemu
2018-02-20 19:12:49 -05:00
Peter Maydell 547fabd58e
osdep.h: Include config-target.h if NEED_CPU_H is defined
NEED_CPU_H is the define we use to distinguish per-target object
compilation from common object compilation. For the former, we must
also include config-target.h so that the .c files see the necessary
CONFIG_ constants.

Backports commit b1e34d1c3a9059e87719634bfc4db53174d63e14 from qemu
2018-02-20 19:11:07 -05:00
Peter Maydell c41bb9a772
osdep.h: Define macros for the benefit of C++ before C++11
For C++ before C++11, <stdint.h> requires definition of the macros
__STDC_CONSTANT_MACROS, __STDC_LIMIT_MACROS and __STDC_FORMAT_MACROS
in order to enable definition of various macros by the header file.
Define these in osdep.h, so that we get the right header file
definitions whether osdep.h is being used by plain C, C++11 or
older C++.

In particular libvixl's header files depend on this and won't
compile if osdep.h is included before them otherwise.

Backports commit 79f56d82f805b170fa2be8c04b682117be56483f from qemu
2018-02-20 19:09:58 -05:00
Lioncash 6094a0373c
softfloat: Remove lingering fast casts 2018-02-20 19:04:22 -05:00
Lioncash c17fa2cad3
osdep.h: Remove int_fast*_t Solaris compatibility code
We now do not use the int_fast*_t types anywhere in QEMU, so we can
remove the compatibility definitions we were providing for the
benefit of ancient Solaris versions.

Backports commit 50fe4df8ee6aba63ae51457bad40ba26e3c9746f from qemu
2018-02-20 18:58:53 -05:00
Peter Maydell 36551f59bb
fpu: Use plain 'int' rather than 'int_fast16_t' for exponents
Use the plain 'int' type rather than 'int_fast16_t' for handling
exponents. Exponents don't need to be exactly 16 bits, so using int16_t
for them would confuse more than it clarified.

This should be a safe change because int_fast16_t semantics
permit use of 'int' (and on 32-bit glibc that is what you get).

Backports commit 0c48262d4772d40677364199372fb6ffcf487558 from qemu
2018-02-20 18:57:32 -05:00
Peter Maydell 9d0463feed
fpu: Use plain 'int' rather than 'int_fast16_t' for shift counts
Use the plain 'int' type rather than 'int_fast16_t' for shift counts
in the various shift related functions, since we don't actually care
about the size of the integer at all here, and using int16_t would
be confusing.

This should be a safe change because int_fast16_t semantics
permit use of 'int' (and on 32-bit glibc that is what you get).

Backports commit 07d792d2b08669bf6a97cbf590496078c4621068 from qemu
2018-02-20 17:01:17 -05:00
Peter Maydell 68cbe1b2ce
fpu: Remove use of int_fast16_t in conversions to int16
Make the functions which convert floating point to 16 bit integer
return int16_t rather than int_fast16_t, and correspondingly use
int_fast16_t in their internal implementations where appropriate.

(These functions are used only by the ARM target.)

Backports commit 0bb721d7217ed4a1abb44f521c5c7ec185062d58 from qemu
2018-02-20 16:54:04 -05:00
Peter Maydell 69d31fbbab
target-mips: Stop using uint_fast*_t types in r4k_tlb_t struct
The r4k_tlb_t structure uses the uint_fast*_t types. Most of these
uses are in bitfields and are thus pointless, because the bitfield
itself specifies the width of the type; just use 'unsigned int'
instead. (On glibc uint_fast16_t is defined as either 32 or 64 bits,
so we know the code is not reliant on it being exactly 16 bits.)
There is also one use of uint_fast8_t, which we replace with uint8_t,
because both are exactly 8 bits on glibc and this is the only
place outside the softfloat code which uses an int_fast*_t type.

Backports commit d783f78933b212537ece77c7ec66866cc2bc0f4d from qemu
2018-02-20 16:48:03 -05:00
Eric Blake e096e62127
qapi: Don't box branches of flat unions
There's no reason to do two malloc's for a flat union; let's just
inline the branch struct directly into the C union branch of the
flat union.

Surprisingly, fewer clients were actually using explicit references
to the branch types in comparison to the number of flat unions
thus modified.

This lets us reduce the hack in qapi-types:gen_variants() added in
the previous patch; we no longer need to distinguish between
alternates and flat unions.

The change to unboxed structs means that u.data (added in commit
cee2dedb) is now coincident with random fields of each branch of
the flat union, whereas beforehand it was only coincident with
pointers (since all branches of a flat union have to be objects).
Note that this was already the case for simple unions - but there
we got lucky. Remember, visit_start_union() blindly returns true
for all visitors except for the dealloc visitor, where it returns
the value !!obj->u.data, and that this result then controls
whether to proceed with the visit to the variant. Pre-patch,
this meant that flat unions were testing whether the boxed pointer
was still NULL, and thereby skipping visit_end_implicit_struct()
and avoiding a NULL dereference if the pointer had not been
allocated. The same was true for simple unions where the current
branch had pointer type, except there we bypassed visit_type_FOO().
But for simple unions where the current branch had scalar type, the
contents of that scalar meant that the decision to call
visit_type_FOO() was data-dependent - the reason we got lucky there
is that visit_type_FOO() for all scalar types in the dealloc visitor
is a no-op (only the pointer variants had anything to free), so it
did not matter whether the dealloc visit was skipped. But with this
patch, we would risk leaking memory if we could skip a call to
visit_type_FOO_fields() based solely on a data-dependent decision.

But notice: in the dealloc visitor, visit_type_FOO() already handles
a NULL obj - it was only the visit_type_implicit_FOO() that was
failing to check for NULL. And now that we have refactored things to
have the branch be part of the parent struct, we no longer have a
separate pointer that can be NULL in the first place. So we can just
delete the call to visit_start_union() altogether, and blindly visit
the branch type; there is no change in behavior except to the dealloc
visitor, where we now unconditionally visit the branch, but where that
visit is now always safe (for a flat union, we can no longer
dereference NULL, and for a simple union, visit_type_FOO() was already
safely handling NULL on pointer types).

Unfortunately, simple unions are not as easy to switch to unboxed
layout; because we are special-casing the hidden implicit type with
a single 'data' member, we really DO need to keep calling another
layer of visit_start_struct(), with a second malloc; although there
are some cleanups planned for simple unions in later patches.

visit_start_union() and gen_visit_implicit_struct() are now unused.
Drop them.

Note that after this patch, the only remaining use of
visit_start_implicit_struct() is for alternate types; the next patch
will do further cleanup based on that fact.

Backports commit 544a3731591f5d53e15f22de00ce5ac758d490b3 from qemu
2018-02-20 16:44:55 -05:00
Eric Blake 12dabf0640
qapi: Don't box struct branch of alternate
There's no reason to do two malloc's for an alternate type visiting
a QAPI struct; let's just inline the struct directly as the C union
branch of the struct.

Surprisingly, no clients were actually using the struct member prior
to this patch outside of the testsuite; an earlier patch in the series
added some testsuite coverage to make the effect of this patch more
obvious.

In qapi.py, c_type() gains a new is_unboxed flag to control when we
are emitting a C struct unboxed within the context of an outer
struct (different from our other two modes of usage with no flags
for normal local variable declarations, and with is_param for adding
'const' in a parameter list). I don't know if there is any more
pythonic way of collapsing the two flags into a single parameter,
as we never have a caller setting both flags at once.

Ultimately, we want to also unbox branches for QAPI unions, but as
that touches a lot more client code, it is better as separate
patches. But since unions and alternates share gen_variants(), I
had to hack in a way to test if we are visiting an alternate type
for setting the is_unboxed flag: look for a non-object branch.
This works because alternates have at least two branches, with at
most one object branch, while unions have only object branches.
The hack will go away in a later patch.

The generated code difference to qapi-types.h is relatively small:

| struct BlockdevRef {
| QType type;
| union { /* union tag is @type */
| void *data;
|- BlockdevOptions *definition;
|+ BlockdevOptions definition;
| char *reference;
| } u;
| };

The corresponding spot in qapi-visit.c calls visit_type_FOO(), which
first calls visit_start_struct() to allocate or deallocate the member
and handle a layer of {} from the JSON stream, then visits the
members. To peel off the indirection and the memory management that
comes with it, we inline this call, then suppress allocation /
deallocation by passing NULL to visit_start_struct(), and adjust the
member visit:

| switch ((*obj)->type) {
| case QTYPE_QDICT:
|- visit_type_BlockdevOptions(v, name, &(*obj)->u.definition, &err);
|+ visit_start_struct(v, name, NULL, 0, &err);
|+ if (err) {
|+ break;
|+ }
|+ visit_type_BlockdevOptions_fields(v, &(*obj)->u.definition, &err);
|+ error_propagate(errp, err);
|+ err = NULL;
|+ visit_end_struct(v, &err);
| break;
| case QTYPE_QSTRING:
| visit_type_str(v, name, &(*obj)->u.reference, &err);

The visit of non-object fields is unchanged.

Backports commit becceedc4d9bc1435099c90a0514945a89844d3a from qemu
2018-02-20 16:32:11 -05:00
Eric Blake dc706426c9
qapi-visit: Use common idiom in gen_visit_fields_decl()
We have several instances of methods that do an early exit if
output is not needed, then log that output is being generated,
and finally produce the output; see qapi-types.py:gen_object()
and qapi-visit.py:gen_visit_implicit_struct(). The odd man
out was gen_visit_fields_decl(); rearrange it to be more like
the others. No semantic change or difference to generated code.

Backports commit 2208d64998c5f867ccee7eeee298971685bf822d from qemu
2018-02-20 16:03:46 -05:00
Eric Blake b513481b9a
qapi: Emit structs used as variants in topological order
Right now, we emit the branches of union types as a boxed pointer,
and it suffices to have a forward declaration of the type. However,
a future patch will swap things to directly use the branch type,
instead of hiding it behind a pointer. For this to work, the
compiler needs the full definition of the type, not just a forward
declaration, prior to the union that is including the branch type.
This patch just adds topological sorting to hoist all types
mentioned in a branch of a union to be fully declared before the
union itself. The sort is always possible, because we do not
allow circular union types that include themselves as a direct
branch (it is, however, still possible to include a branch type
that itself has a pointer to the union, for a type that can
indirectly recursively nest itself - that remains safe, because
that the member of the branch type will remain a pointer, and the
QMP representation of such a type adds another {} for each recurring
layer of the union type).

Backports commit 1de5d4ca0752138034305f3d4e8fe17ef6503569 from qemu
2018-02-20 16:02:29 -05:00
Eric Blake f5c93aa7ab
qapi-visit: Less indirection in visit_type_Foo_fields()
We were passing 'Foo **obj' to the internal helper function, but
all uses within the helper were via reads of '*obj'. Refactor
things to pass one less level of indirection, by having the
callers dereference before calling.

For an example of the generated code change:

|-static void visit_type_BalloonInfo_fields(Visitor *v, BalloonInfo **obj, Error **errp)
|+static void visit_type_BalloonInfo_fields(Visitor *v, BalloonInfo *obj, Error **errp)
| {
| Error *err = NULL;
|
|- visit_type_int(v, "actual", &(*obj)->actual, &err);
|+ visit_type_int(v, "actual", &obj->actual, &err);
| error_propagate(errp, err);
| }
|
|@@ -261,7 +261,7 @@ void visit_type_BalloonInfo(Visitor *v,
| if (!*obj) {
| goto out_obj;
| }
|- visit_type_BalloonInfo_fields(v, obj, &err);
|+ visit_type_BalloonInfo_fields(v, *obj, &err);
| out_obj:

The refactoring will also make it easier to reuse the helpers in
a future patch when implicit structs are stored directly in the
parent struct rather than boxed through a pointer.

Backports commit 655519030b5d20967ae3afa1fe91ef5ad4406065 from qemu
2018-02-20 16:00:37 -05:00
Markus Armbruster 553e946627
qapi-visit: Unify struct and union visit
gen_visit_union() is now just like gen_visit_struct(). Rename
it to gen_visit_object(), use it for structs, and drop
gen_visit_struct(). Output is unchanged.

Backports commit 59d9e84cc94b8268f13ec184acfb997e8f352593 from qemu
2018-02-20 15:55:06 -05:00
Eric Blake 155c507ed4
qapi: Visit variants in visit_type_FOO_fields()
We initially created the static visit_type_FOO_fields() helper
function for reuse of code - we have cases where the initial
setup for a visit has different allocation (depending on whether
the fields represent a stand-alone type or are embedded as part
of a larger type), but where the actual field visits are
identical once a pointer is available.

Up until the previous patch, visit_type_FOO_fields() was only
used for structs (no variants), so it was covering every field
for each type where it was emitted.

Meanwhile, the code for visiting unions looks like:

static visit_type_U_fields() {
visit base;
visit local_members;
}
visit_type_U() {
visit_start_struct();
visit_type_U_fields();
visit variants;
visit_end_struct();
}

which splits the fields of the union visit across two functions.
Move the code to visit variants to live inside visit_type_U_fields(),
while making it conditional on having variants so that all other
instances of the helper function remain unchanged. This is also
a step closer towards unifying struct and union visits, and towards
allowing one union type to be the branch of another flat union.

The resulting diff to the generated code is a bit hard to read,
but it can be verified that it touches only union types, and that
the end result is the following general structure:

static visit_type_U_fields() {
visit base;
visit local_members;
visit variants;
}
visit_type_U() {
visit_start_struct();
visit_type_U_fields();
visit_end_struct();
}

Backports commit 9a5cd424d5f06fb5293eb264456d89343c557558 from qemu
2018-02-20 15:53:30 -05:00
Markus Armbruster 428eadd9e0
qapi-visit: Simplify how we visit common union members
For a simple union SU, gen_visit_union() generates a visit of its
single tag member, like this:

visit_type_SUKind(v, "type", &(*obj)->type, &err);

For a flat union FU with base B, it generates a visit of its base
fields:

visit_type_B_fields(v, (B **)obj, &err);

Instead, we can simply visit the common members using the same fields
visit function we use for structs, generated with
gen_visit_struct_fields(). This function visits the base if any, then
the local members.

For a simple union SU, visit_type_SU_fields() contains exactly the old
tag member visit, because there is no base, and the tag member is the
only member. For instance, the code generated for qapi-schema.json's
KeyValue changes like this:

+static void visit_type_KeyValue_fields(Visitor *v, KeyValue **obj, Error **errp)
+{
+ Error *err = NULL;
+
+ visit_type_KeyValueKind(v, "type", &(*obj)->type, &err);
+ if (err) {
+ goto out;
+ }
+
+out:
+ error_propagate(errp, err);
+}
+
void visit_type_KeyValue(Visitor *v, const char *name, KeyValue **obj, Error **errp)
{
Error *err = NULL;
@@ -4863,7 +4911,7 @@ void visit_type_KeyValue(Visitor *v, con
if (!*obj) {
goto out_obj;
}
- visit_type_KeyValueKind(v, "type", &(*obj)->type, &err);
+ visit_type_KeyValue_fields(v, obj, &err);
if (err) {
goto out_obj;
}

For a flat union FU, visit_type_FU_fields() contains exactly the old
base fields visit, because there is a base, but no members. For
instance, the code generated for qapi-schema.json's CpuInfo changes
like this:

static void visit_type_CpuInfoBase_fields(Visitor *v, CpuInfoBase **obj, Error **errp);

+static void visit_type_CpuInfo_fields(Visitor *v, CpuInfo **obj, Error **errp)
+{
+ Error *err = NULL;
+
+ visit_type_CpuInfoBase_fields(v, (CpuInfoBase **)obj, &err);
+ if (err) {
+ goto out;
+ }
+
+out:
+ error_propagate(errp, err);
+}
+
static void visit_type_CpuInfoX86_fields(Visitor *v, CpuInfoX86 **obj, Error **errp)
...
@@ -3485,7 +3509,7 @@ void visit_type_CpuInfo(Visitor *v, cons
if (!*obj) {
goto out_obj;
}
- visit_type_CpuInfoBase_fields(v, (CpuInfoBase **)obj, &err);
+ visit_type_CpuInfo_fields(v, obj, &err);
if (err) {
goto out_obj;
}

As you see, the generated code grows a bit, but in practice, it's lost
in the noise: qapi-schema.json's qapi-visit.c gains roughly 1%.

This simplification became possible with commit 441cbac "qapi-visit:
Convert to QAPISchemaVisitor, fixing bugs". It's a step towards
unifying gen_struct() and gen_union().

Backports commit d7445b57f4342d50c25b5bc1746048fa3720511b from qemu
2018-02-20 15:48:54 -05:00
Eric Blake 74da8f0eea
qapi: Forbid 'any' inside an alternate
The whole point of an alternate is to allow some type-safety while
still accepting more than one JSON type. Meanwhile, the 'any'
type exists to bypass type-safety altogether. The two are
incompatible: you can't accept every type, and still tell which
branch of the alternate to use for the parse; fix this to give a
sane error instead of a Python stack trace.

Note that other types that can't be alternate members are caught
earlier, by check_type().

Backports commit 46534309e667fd860720f983c2c9aefe0354340d from qemu
2018-02-20 15:47:16 -05:00
Eric Blake 907771516e
qapi: Forbid empty unions and useless alternates
Empty unions serve no purpose, and while we compile with gcc
which permits them, strict C99 forbids them. We happen to inject
a dummy 'void *data' member into the C unions that represent QAPI
unions and alternates, but we want to get rid of that member (it
pollutes the namespace for no good reason), which would leave us
with an empty union if the user didn't provide any branches. While
empty structs make sense in QAPI, empty unions don't add any
expressiveness to the QMP language. So prohibit them at parse
time. Update the documentation and testsuite to match.

Note that the documentation already mentioned that alternates
should have "two or more JSON data types"; so this also fixes
the code to enforce that. However, we have existing uses of a
union type with only one branch, so the 2-or-more strictness
is intentionally limited to alternates.

Backports commit 02a57ae32b08e8981b59979b80e682c9a153e94d from qemu
2018-02-20 15:46:08 -05:00
Eric Blake fa6af0733a
qapi-visit: Honor prefix of discriminator enum
When we added support for a user-specified prefix for an enum
type (commit 351d36e), we forgot to teach the qapi-visit code
to honor that prefix in the case of using a prefixed enum as
the discriminator for a flat union. While there is still some
on-list debate on whether we want to keep prefixes, we should
at least make it work as long as it is still part of the code
base.

Backports commit 9d3524b39e1fe5f3bb7a990ad7841e469e954a3b from qemu
2018-02-20 15:38:44 -05:00
Alistair Francis a8807cd3b9
target-arm: Add PMUSERENR_EL0 register
The Linux kernel accesses this register early in its setup.

Backports commit 8a83ffc2dafad3499b87a736b17ab1b203fdb00b from qemu
2018-02-20 15:36:31 -05:00
Lioncash b29e024f56
target-arm: Correct bad VBAR patch merge 2018-02-20 15:34:32 -05:00
Alistair Francis 2945893f40
target-arm: Add the pmovsclr_el0 and pmintenclr_el1 registers
Backports commit 978364f12adebb4b8d90fdeb71242cb3c1405740 from qemu
2018-02-20 15:27:50 -05:00
Alistair Francis c31856e34e
target-arm: Add the pmceid0 and pmceid1 registers
Backports commit 4054bfa9e7986c9b7d2bf70f9e10af9647e376fc from qemu
2018-02-20 15:22:41 -05:00
Peter Maydell 57a9474cc7
target-arm: UNDEF in the UNPREDICTABLE SRS-from-System case
Make get_r13_banked() raise an exception at runtime for the
corner case of SRS from System mode, so that we can UNDEF it;
this brings us in to line with the ARM ARM's set of permitted
CONSTRAINED UNPREDICTABLE choices.

Backports commit f01377f591fe15c652f947646c4a69a7d4a71ad9 from qemu
2018-02-20 15:12:25 -05:00
Peter Maydell 88d21504e4
target-arm: Combine user-only and softmmu get/set_r13_banked()
The user-mode versions of get/set_r13_banked() exist just to assert
if they're ever called -- the translate time code should never
emit calls to them because SRS from user mode always UNDEF.
There's no code in the softmmu versions that can't compile in
CONFIG_USER_ONLY, and the assertion is not particularly useful,
so combine the two functions rather than having completely split
versions under ifdefs.

Backports commit d86d57d4fe683c99823f625f941eff26c07c72c3 from qemu
2018-02-20 15:09:58 -05:00
Peter Maydell 3d4f8b2d8f
target-arm: Move get/set_r13_banked() to op_helper.c
Move get/set_r13_banked() from helper.c to op_helper.c. This will
let us add exception-raising code to them, and also puts them
in the same file as get/set_user_reg(), which makes some conceptual
sense.

(The original reason for the helper.c/op_helper.c split was that
only op_helper.c had access to the CPU env pointer; this distinction
has not been true for a long time, though, and so the split is
now rather arbitrary.)

Backports commit 72309cee482868d6c4711931c3f7e02ab9dec229 from qemu

target-arm: Move bank_number() into internals.h

Move bank_number()'s implementation into internals.h, so
it's available in the user-mode-only compile as well.

Backports commit c766568d3604082c6fd45cbabe42c48e4861a13f from qemu
2018-02-20 15:09:07 -05:00
Peter Maydell a6aac0dbb4
target-arm: Clean up trap/undef handling of SRS
The SRS instruction is:
* UNDEFINED in Hyp mode
* UNPREDICTABLE in User or System mode
* UNPREDICTABLE if the specified mode isn't accessible
* trapped to EL3 if EL3 is AArch64 and we are at Secure EL1

Clean up the code to handle all these cases cleanly, including
picking UNDEF as our choice of UNPREDICTABLE behaviour rather
blindly trusting the mode field passed in the instruction.
As part of this, move the check for IS_USER into gen_srs()
itself rather than having it done by the caller.

The exception is that we don't UNDEF for calls from System
mode, which need a runtime check. This will be dealt with in
the following commits.

Backports commit cbc0326b6fb905f80b7cef85b24571f7ebb62077 from qemu
2018-02-20 15:02:45 -05:00
Peter Maydell 56a88557db
target-arm: Report correct syndrome for FPEXC32_EL2 traps
If access to FPEXC32_EL2 is trapped by CPTR_EL2.TFP or CPTR_EL3.TFP,
this should be reported with a syndrome register indicating an
FP access trap, not one indicating a system register access trap.

Backports commit f2cae6092767aaf418778eada15be444c23883be from qemu
2018-02-20 15:00:32 -05:00
Peter Maydell 425db8c149
target-arm: Implement MDCR_EL3.TDA and MDCR_EL2.TDA traps
Implement the debug register traps controlled by MDCR_EL2.TDA
and MDCR_EL3.TDA.

Backports commit d6c8cf815171e35e0b1ef4e0cff602ab3d575747 from qemu
2018-02-20 14:58:52 -05:00
Peter Maydell 7295676caf
target-arm: Implement MDCR_EL2.TDRA traps
Implement trapping of the "debug ROM" registers, which are controlled
by MDCR_EL2.TDRA for EL2 but by the more general MDCR_EL3.TDA for EL3.

Backports commit 91b0a23865558e2ce9c2e7042d404e8bf2e4b817 from qemu
2018-02-20 14:54:53 -05:00
Peter Maydell 537ff96e34
target-arm: Implement MDCR_EL3.TDOSA and MDCR_EL2.TDOSA traps
Implement the traps to EL2 and EL3 controlled by the bits
MDCR_EL2.TDOSA MDCR_EL3.TDOSA. These can configurably trap
accesses to the "powerdown debug" registers.

Backports commit 187f678d5c28251dba2b44127e59966b14518ef7 from qemu
2018-02-20 14:52:47 -05:00
Peter Maydell 871dee4908
target-arm: Fix handling of SCR.SMD
We weren't quite implementing the handling of SCR.SMD correctly.
The condition governing whether the SMD bit should apply only
for NS state is "is EL3 is AArch32", not "is the current EL AArch32".
Fix the condition, and clarify the comment both to reflect this and
to expand slightly on what's going on for the v7-no-Virtualization case.

Backports commit f096e92b6385fd87e8ea948ad3af70faf752c13a from qemu
2018-02-20 14:50:33 -05:00
Peter Maydell 7b503db3c6
target-arm: correct CNTFRQ access rights
Correct some corner cases we were getting wrong for
CNTFRQ access rights:
* should UNDEF from 32-bit Secure EL1
* only writable from the highest implemented exception level,
which might not be EL1 now

To clarify the code, provide a new utility function
arm_highest_el() which returns the highest implemented
exception level.

Backports commit 755026728abb19fba70e6b4396a27fa2e7550d74 from qemu
2018-02-20 14:49:28 -05:00
Richard Henderson 22d4f95912
target-i386: Implement FSGSBASE
Backports commit 07929f2ab2ab9c9e01d4ae79f48f2b2476b715c8 from qemu
2018-02-20 14:45:58 -05:00
Richard Henderson 6ca787fb48
target-i386: Enable CR4/XCR0 features for user-mode
Backports commit a114d25d5b42600871d75929604c0b9fcc448ec0 from qemu
2018-02-20 14:37:33 -05:00
Richard Henderson 86cc5862a1
target-i386: Clear bndregs during legacy near jumps
Backports commit 7d117ce81ef6258cdcc0d24c774d045fa4b5fd26 from qemu
2018-02-20 14:36:11 -05:00
Richard Henderson 8ca89461b5
target-i386: Implement BNDLDX, BNDSTX
Backports commit bdd87b3b591add6e4d7c6b6125fcf0d706cc8bc4 from qemu
2018-02-20 14:32:48 -05:00
Richard Henderson f30c3efd0e
target-i386: Implement BNDLDX, BNDSTX
Backports commit bdd87b3b591add6e4d7c6b6125fcf0d706cc8bc4 from qemu
2018-02-20 14:26:18 -05:00
Richard Henderson a02626afe7
target-i386: Update BNDSTATUS for exceptions raised by BOUND
Backports commit 75d14edcf5fd9d5bb614554539799abaaeab3166 from qemu
2018-02-20 14:24:07 -05:00
Richard Henderson 554c41f05f
target-i386: Implement BNDCL, BNDCU, BNDCN
Backports commit 523e28d7614571680d21641bd0bd9b9e84570cee from qemu
2018-02-20 14:22:46 -05:00
Richard Henderson c2f92123f4
target-i386: Implement BNDMOV
Backports commit 62b58ba58bfebdb8a1c447beaa1285cc21249d15 from qemu
2018-02-20 14:14:39 -05:00
Richard Henderson 8bc3037864
target-i386: Implement BNDMK
Backports commit 149b427b32de358c3bd5bc064c50acca6e9ff78f from qemu
2018-02-20 14:02:31 -05:00
Richard Henderson e11a7bcede
target-i386: Split up gen_lea_modrm
This is immediately usable by lea and multi-byte nop,
and will be required to implement parts of the mpx spec.

Backports commit a074ce42a3186bd9f96ef541bb2e01419181dae3 from qemu
2018-02-20 13:49:05 -05:00
Richard Henderson 159e837a6c
target-i386: Perform set/reset_inhibit_irq inline
With helpers that can be reused for other things.

Backports commit 7f0b7141b4c7deab51efd8ee1e83eab2d9b7a9ea from qemu
2018-02-20 13:34:47 -05:00
Richard Henderson cacb60b57b
target-i386: Enable control registers for MPX
Enable and disable at CPL changes, MSR changes, and XRSTOR changes.

Backports commit f4f1110e4b34797ddfa87bb28f9518b9256778be from qemu
2018-02-20 13:27:46 -05:00
Richard Henderson 7a7a72f49b
target-i386: Implement XSAVEOPT
Backports commit c9cfe8f9fb21f086e24b3a8f7ccd9c06e4d8d9d6 from qemu
2018-02-20 12:52:10 -05:00
Richard Henderson 6c5b6a0e7f
target-i386: Add XSAVE extension
This includes XSAVE, XRSTOR, XGETBV, XSETBV, which are all related,
as well as the associate cpuid bits.

Backports commit 19dc85dba23c0db1ca932c62e453c37e00761628 from qemu
2018-02-20 12:47:52 -05:00
Richard Henderson 6657c0c54a
target-i386: Rearrange processing of 0F AE
Rather than nesting tests of OP, MOD, and RM, decode them all at once
with a switch. Also, add some missing #UD checks for e.g. incorrect
LOCK prefix.

Backports commit 121f3157887f92268a3d6169e2d4601f9292020b from qemu
2018-02-20 12:36:54 -05:00
Richard Henderson cb536601cb
target-i386: Rearrange processing of 0F 01
Rather than nesting tests of OP, MOD, and RM, decode them
all at once with a switch. Fixes incorrect decoding of
AMD Pacifica extensions (aka vmrun et al) via op==2 path.

Backports commit 1906b2af7c2345037d9b2fdf484b457b5acd09d1 from qemu
2018-02-20 12:32:45 -05:00
Richard Henderson b490486028
target-i386: Split fxsave/fxrstor implementation
We will be able to reuse these pieces for XSAVE/XRSTOR.

Backports commit 64dbaff09bb768dbbb13142862554f18ab642866 from qemu
2018-02-20 11:58:00 -05:00
Alistair Francis a4bf026460
qom: Correct object_property_get_int() description
The description of object_property_get_int() stated that on an error
it returns NULL. This is not the case and the function will return -1
if an error occurs. Update the commented documentation accordingly.

Backports commit b29b47e9b35017428904e0e934700877dfaabe73 from qemu
2018-02-20 11:52:16 -05:00
Sergey Fedorov dfb78118ff
target-arm: Implement checking of fired watchpoint
ARM stops before access to a location covered by watchpoint. Also, QEMU
watchpoint fire is not necessarily an architectural watchpoint match.
Unfortunately, that is hardly possible to ignore a fired watchpoint in
debug exception handler. So move watchpoint check from debug exception
handler to the dedicated watchpoint checking callback.

Backports commit 3826121d9298cde1d29ead05910e1f40125ee9b0 from qemu
2018-02-20 11:50:29 -05:00
Sergey Fedorov 6a3038db7c
cpu: Add callback to check architectural watchpoint match
When QEMU watchpoint matches, that is not definitely an architectural
watchpoint match yet. If it is a stop-before-access watchpoint then that
is hardly possible to ignore it after throwing a TCG exception.

A special callback is introduced to check for architectural watchpoint
match before raising a TCG exception.

Backports commit 568496c0c0f1863a4bc18539962cd8d81baa4e30 from qemu
2018-02-20 11:43:56 -05:00
Peter Maydell 3d5b54cf4b
target-arm: Fix IL bit reported for Thumb VFP and Neon traps
All Thumb Neon and VFP instructions are 32 bits, so the IL
bit in the syndrome register should be set. Pass false to the
syn_* function's is_16bit argument rather than s->thumb
so we report the correct IL bit.

Backports commit 7d197d2db5e99e4c8b20f6771ddc7303acaa1c89 from qemu
2018-02-20 11:39:39 -05:00
Peter Maydell 5b8ad0e2fc
target-arm: Fix IL bit reported for Thumb coprocessor traps
All Thumb coprocessor instructions are 32 bits, so the IL
bit in the syndrome register should be set. Pass false to the
syn_* function's is_16bit argument rather than s->thumb
so we report the correct IL bit.

Backports commit 4df322593037d2700f72dfdfb967300b7ad2e696 from qemu
2018-02-20 11:38:27 -05:00
Peter Maydell 814bffc1ee
target-arm: Correct misleading 'is_thumb' syn_* parameter names
In syndrome register values, the IL bit indicates the instruction
length, and is 1 for 4-byte instructions and 0 for 2-byte
instructions. All A64 and A32 instructions are 4-byte, but
Thumb instructions may be either 2 or 4 bytes long. Unfortunately
we named the parameter to the syn_* functions for constructing
syndromes "is_thumb", which falsely implies that it should be
set for all Thumb instructions, rather than only the 16-bit ones.
Fix the functions to name the parameter 'is_16bit' instead.

Backports commit fc05f4a62c568b607ec3fe428a419bb38205b570 from qemu
2018-02-20 11:36:55 -05:00
Peter Maydell a3ff1c4a65
target-arm: Enable EL3 for Cortex-A53 and Cortex-A57
Enable EL3 support for our Cortex-A53 and Cortex-A57 CPU models.
We have enough implemented now to be able to run real world code
at least to some extent (I can boot ARM Trusted Firmware to the
point where it pulls in OP-TEE and then falls over because it
doesn't have a UEFI image it can chain to).

Backports commit 3ad901bc2b98f5539af9a7d4aef140a6d8fa6442 from qemu
2018-02-20 11:31:44 -05:00
Peter Maydell aecf7b05dc
target-arm: Implement NSACR trapping behaviour
Implement some corner cases of the behaviour of the NSACR
register on ARMv8:
* if EL3 is AArch64 then accessing the NSACR from Secure EL1
with AArch32 should trap to EL3
* if EL3 is not present or is AArch64 then reads from NS EL1 and
NS EL2 return constant 0xc00

It would in theory be possible to implement all these with
a single reginfo definition, but for clarity we use three
separate definitions for the three cases and install the
right one based on the CPU feature flags.

Backports commit 2f027fc52d4b444a47cb05a9c96697372a6b57d2 from qemu
2018-02-20 11:29:29 -05:00
Peter Maydell 6dbc781ce3
target-arm: Add isread parameter to CPAccessFns
System registers might have access requirements which need to
be described via a CPAccessFn and which differ for reads and
writes. For this to be possible we need to pass the access
function a parameter to tell it whether the access being checked
is a read or a write.

Backports commit 3f208fd76bcc91a8506681bb8472f2398fe6f487 from qemu
2018-02-20 11:24:17 -05:00
Peter Maydell 4838c1dfe9
target-arm: Update arm_generate_debug_exceptions() to handle EL2/EL3
The arm_generate_debug_exceptions() function as originally implemented
assumes no EL2 or EL3. Since we now have much more of an implementation
of those now, fix this assumption.

Backports commit 533e93f1cf12c570aab45f14663dab6fb8ea3ffc from qemu
2018-02-20 11:12:36 -05:00
Peter Maydell 4552444928
target-arm: Use access_trap_aa32s_el1() for SCR and MVBAR
The registers MVBAR and SCR should have the behaviour of trapping to
EL3 if accessed from Secure EL1, but we were incorrectly implementing
them to UNDEF (which would trap to EL1). Fix this by using the new
access_trap_aa32s_el1() access function.

Backports commit efe4a274083f61484a8f1478d93f229d43aa8095 from qemu
2018-02-20 11:10:38 -05:00
Peter Maydell c0411e5422
target-arm: Implement MDCR_EL3 and SDCR
Implement the MDCR_EL3 register (which is SDCR for AArch32).
For the moment we implement it as reads-as-written.

Backports commit 5513c3abed8e5fabe116830c63f0d3fe1f94bd21 from qemu
2018-02-20 11:08:15 -05:00
Peter Maydell a2fd906e8b
target-arm: Fix typo in comment in arm_is_secure_below_el3()
Fix a typo where "EL2" was written but "EL3" intended.

Backports commit 6b7f0b61f080b886c9b4bba8240379ce90e20b12 from qemu
2018-02-20 11:05:14 -05:00
Paolo Bonzini 98452daad6
target-i386: fix PSE36 mode
(pde & 0x1fe000) is a 32-bit integer; when shifting it
into bits 39-32 the result is zero. Fix it by making the
mask (and thus the result of the AND) a 64-bit integer.

Reported by Coverity.

Backports commit 388ee48a88e684e719660a2cae9c21897b94fa37 from qemu
2018-02-20 11:03:49 -05:00
Richard Henderson 65a78ebb26
target-i386: Deconstruct the cpu_T array
All references to cpu_T are done with a constant index. It aids
readability to decompose the array into two scalar variables.

Backports commit 1d1cc4d0f481b2939c7e9f6606e571b2fc81971a from qemu
2018-02-20 11:02:34 -05:00
Richard Henderson 5d45260df7
target-i386: Tidy gen_add_A0_im
Merge gen_op_addl_A0_im and gen_op_addq_A0_im into gen_add_A0_im
and clean up the ifdef.

Replace the one remaining user of gen_op_addl_A0_im with gen_add_A0_im.

Backports commit 4e85057b92d214decf10045d3d4faa2faf33d100 from qemu
2018-02-20 10:20:04 -05:00
Richard Henderson 0004dfcba3
target-i386: Rewrite leave
Unify the code across stack pointer widths. Fix the note about
not updating ESP before the potential exception.

Backports commit 2045f04c3ae030bda650f84035f114bbd84909a9 from qemu
2018-02-20 10:16:56 -05:00
Richard Henderson 7dd4fcc621
target-i386: Rewrite gen_enter inline
Use gen_lea_v_seg for centralized segment base knowledge. Unify
code across 32- and 64-bit. Fix note about "must save state"
before using the out-of-line helpers.

Backports commit 743e398e2fbf2f7183bf7a53c9d011fabcaa1770 from qemu
2018-02-20 10:13:43 -05:00
Richard Henderson 302752df8b
target-i386: Use gen_lea_v_seg in pusha/popa
More centralization of handling of segment bases.
Also fixes the note about 16-bit wrap around not fully handled.

Backports commit d37ea0c04723f3e15fde55fe97cff6278159929b from qemu
2018-02-20 10:07:46 -05:00
Richard Henderson 092c7bea97
target-i386: Access segs via TCG registers
Having segs[].base as a register significantly improves code
generation for real and protected modes, particularly for TBs
that have multiple memory references where the segment base
can be held in a hard register through the TB.

Backports commit 3558f8055f37a34762b7a2a0f02687e6eeab893d from qemu
2018-02-20 10:02:37 -05:00
Richard Henderson 969f8ab407
target-i386: Use gen_lea_v_seg in stack subroutines
I.e. gen_push_v, gen_pop_T0, gen_stack_A0.
More centralization of handling of segment bases.

Backports commit 77ebcad04f3659fa7eb799928fdd68280fac720d from qemu
2018-02-20 09:28:40 -05:00
Richard Henderson 0d1766a9f0
target-i386: Use gen_lea_v_seg in gen_lea_modrm
Centralize handling of segment bases.

Backports commit d6a2914984c89fa0a3125b9842e0cbf68de79a3d from qemu
2018-02-20 09:23:49 -05:00
Richard Henderson f3220dbb8c
target-i386: Introduce mo_stacksize
Centralize computation of a MO_SIZE for the stack pointer.

Backports commit 64ae256c2450262e27f07657c5734d3197458d95 from qemu
2018-02-20 09:18:48 -05:00
Richard Henderson 63c4e79870
target-i386: Create gen_lea_v_seg
Add forgotten zero-extension in the TARGET_X86_64, !CODE64, ss32 case;
use this new function to implement gen_string_movl_A0_EDI,
gen_string_movl_A0_ESI, gen_add_A0_ds_seg.

Backports commit ca2f29f555805d07fb0b9ebfbbfc4e3656530977 from qemu
2018-02-20 09:17:13 -05:00
Lioncash c658126845
include: Move RAMList to ramlist.h
Moves the struct back into qemu's headers
2018-02-20 08:47:51 -05:00
Lioncash cdd4003ce9
Move RAMBlock to ram_addr.h
Moves it back into qemu's includes.
2018-02-20 08:35:44 -05:00
Paolo Bonzini cbc56b3ceb
memory: add early bail out from cpu_physical_memory_set_dirty_range
This condition is true in the common case, so we can cut out the body of
the function. In addition, this makes it easier for the compiler to do
at least partial inlining, even if it decides that fully inlining the
function is unreasonable.

Backports commit 8bafcb21643a39a5b29109f8bd5ee5a6f0f6850b from qemu
2018-02-20 08:32:10 -05:00
Lioncash a268815478
include: Add stubbed xen function
Will allow us to not comment out code all the time for xen checks (ideally)
2018-02-20 08:29:58 -05:00
Markus Armbruster 91b4e76fef
error: New error_fatal
Similar to error_abort, but doesn't report where the error was
created, and terminates the process with exit(1) rather than abort().

Backports commit a29a37b994ca3c5a1d39fa0e8934f7e0f2cf57ef from qemu
2018-02-20 08:22:27 -05:00
Markus Armbruster c4a06e2d12
error: Improve documentation some more
Don't claim error_report_err() always reports to stderr. It actually
reports to the current monitor when we have one.

Clarify intended use of error_abort and error_fatal.

Backports commit 10303f04b98efa76e638b9ae4632688f56f088fc from qemu
2018-02-20 08:13:39 -05:00
Eric Blake 0c04f85d31
qapi: Fix compilation failure on MIPS and SPARC
Commit 86f4b687 broke compilation on MIPS and SPARC, which have a
preprocessor pollution of '#define mips 1' and '#define sparc 1',
respectively. Treat it the same way as we do for the pollution with
'unix', so that QMP remains backwards compatible and only the C code
needs to use the alternative 'q_mips', 'q_sparc' spelling.

Backports commit 86ae191163d48ff4ff9d9996868e6cfe92a82449 from qemu
2018-02-20 08:11:01 -05:00
Eric Blake 49b8891872
qmp: Don't abuse stack to track qmp-output root
The previous commit documented an inconsistency in how we are
using the stack of qmp-output-visitor. Normally, pushing a
single top-level object puts the object on the stack twice:
once as the root, and once as the current container being
appended to; but popping that struct only pops once. However,
qmp_ouput_add() was trying to either set up the added object
as the new root (works if you parse two top-level scalars in a
row: the second replaces the first as the root) or as a member
of the current container (works as long as you have an open
container on the stack; but if you have popped the first
top-level container, it then resolves to the root and still
tries to add into that existing container).

Fix the stupidity by not tracking two separate things in the
stack. Drop the now-useless qmp_output_first() and
qmp_output_last() while at it.

Saved for a later patch: we still are rather sloppy in that
qmp_output_get_object() can be called in the middle of a parse,
rather than requiring that a visit is complete.

Backports commit 455ba08afde784466420449d01c6458f88349d55 from qemu
2018-02-20 08:09:56 -05:00
Eric Blake 25dad6e8d5
qmp: Fix reference-counting of qnull on empty output visit
Commit 6c2f9a15 ensured that we would not return NULL when the
caller used an output visitor but had nothing to visit. But
in doing so, it added a FIXME about a reference count leak
that could abort qemu in the (unlikely) case of SIZE_MAX such
visits (more plausible on 32-bit). (Although that commit
suggested we might fix it in time for 2.5, we ran out of time;
fortunately, it is unlikely enough to bite that it was not
worth worrying about during the 2.5 release.)

This fixes things by documenting the internal contracts, and
explaining why the internal function can return NULL and only
the public facing interface needs to worry about qnull(),
thus avoiding over-referencing the qnull_ global object.

It does not, however, fix the stupidity of the stack mixing
up two separate pieces of information; add a FIXME to explain
that issue, which will be fixed shortly in a future patch.

Backports commit a86156401559cb4401cf9ecc704faeab6fc8bb19 from qemu
2018-02-20 08:07:31 -05:00
Eric Blake a2fc66a005
qapi: Tighten qmp_input_end_list()
The only way that qmp_input_pop() will set errp is if a dictionary
was the most recent thing pushed. Since we don't have any
push(struct)/pop(list) or push(list)/pop(struct) mismatches (such
a mismatch is a programming bug), we therefore cannot set errp
inside qmp_input_end_list(). Make this obvious by
using &error_abort. A later patch will then remove the errp
parameter of qmp_input_pop(), but that will first require the
larger task of splitting visit_end_struct().

Backports commit bdd8e6b5d8a9def83d491a3f41c10424fc366258 from qemu
2018-02-19 23:44:45 -05:00
Eric Blake 1f54314cbb
qapi: Drop unused 'kind' for struct/enum visit
visit_start_struct() and visit_type_enum() had a 'kind' argument
that was usually set to either the stringized version of the
corresponding qapi type name, or to NULL (although some clients
didn't even get that right). But nothing ever used the argument.
It's even hard to argue that it would be useful in a debugger,
as a stack backtrace also tells which type is being visited.

Therefore, drop the 'kind' argument as dead.

Backports commit 337283dffbb5ad5860ed00408a5fd0665c21be07 from qemu
2018-02-19 23:43:54 -05:00
Eric Blake 844c136945
qapi: Swap 'name' in visit_* callbacks to match public API
As explained in the previous patches, matching argument order of
'name, &value' to JSON's "name":value makes sense. However,
while the last two patches were easy with Coccinelle, I ended up
doing this one all by hand. Now all the visitor callbacks match
the main interface.

The compiler is able to enforce that all clients match the changed
interface in visitor-impl.h, even where two pointers are being
swapped, because only one of the two pointers is const (if that
were not the case, then C's looseness on treating 'char *' like
'void *' would have made review a bit harder).

Backports commit 0b2a0d6bb2446060944061e53e87d0c7addede79 from qemu
2018-02-19 23:36:52 -05:00
Eric Blake 4100f3b78a
qapi: Consolidate visitor small integer callbacks
Commit 4e27e819 introduced optional visitor callbacks for all
sorts of int types, but no visitor has supplied any of the
callbacks for sizes less than 64 bits. In other words, the
generic implementation based on using type_[u]int64() followed
by bounds-checking works just fine. In the interest of
simplicity, it's easier to make the visitor callback interface
not have to worry about the other sizes.

Adding some helper functions minimizes the boilerplate required
to correct FIXMEs added earlier with regards to questionable
reuse of errp, particularly now that we can guarantee from a
single file audit that value is unchanged if an error is set.

Backports commit 04e070d217b4414f1f91aa8ad25fc0ae7ca0be93 from qemu
2018-02-19 23:21:56 -05:00
Eric Blake 9ec25b4673
qom: Swap 'name' next to visitor in ObjectPropertyAccessor
Similar to the previous patch, it's nice to have all functions
in the tree that involve a visitor and a name for conversion to
or from QAPI to consistently stick the 'name' parameter next
to the Visitor parameter.

Done by manually changing include/qom/object.h and qom/object.c,
then running this Coccinelle script and touching up the fallout
(Coccinelle insisted on adding some trailing whitespace).

@ rule1 @
identifier fn;
typedef Object, Visitor, Error;
identifier obj, v, opaque, name, errp;
@@
void fn
- (Object *obj, Visitor *v, void *opaque, const char *name,
+ (Object *obj, Visitor *v, const char *name, void *opaque,
Error **errp) { ... }

@@
identifier rule1.fn;
expression obj, v, opaque, name, errp;
@@
fn(obj, v,
- opaque, name,
+ name, opaque,
errp)

Backports commit d7bce9999df85c56c8cb1fcffd944d51bff8ff48 from qemu
2018-02-19 23:14:37 -05:00
Eric Blake 5dd5646a9a
qapi: Swap visit_* arguments for consistent 'name' placement
JSON uses "name":value, but many of our visitor interfaces were
called with visit_type_FOO(v, &value, name, errp). This can be
a bit confusing to have to mentally swap the parameter order to
match JSON order. It's particularly bad for visit_start_struct(),
where the 'name' parameter is smack in the middle of the
otherwise-related group of 'obj, kind, size' parameters! It's
time to do a global swap of the parameter ordering, so that the
'name' parameter is always immediately after the Visitor argument.

Additional reason in favor of the swap: the existing include/qjson.h
prefers listing 'name' first in json_prop_*(), and I have plans to
unify that file with the qapi visitors; listing 'name' first in
qapi will minimize churn to the (admittedly few) qjson.h clients.

Later patches will then fix docs, object.h, visitor-impl.h, and
those clients to match.

Done by first patching scripts/qapi*.py by hand to make generated
files do what I want, then by running the following Coccinelle
script to affect the rest of the code base:
$ spatch --sp-file script `git grep -l '\bvisit_' -- '**/*.[ch]'`
I then had to apply some touchups (Coccinelle insisted on TAB
indentation in visitor.h, and botched the signature of
visit_type_enum() by rewriting 'const char *const strings[]' to
the syntactically invalid 'const char*const[] strings'). The
movement of parameters is sufficient to provoke compiler errors
if any callers were missed.

// Part 1: Swap declaration order
@@
type TV, TErr, TObj, T1, T2;
identifier OBJ, ARG1, ARG2;
@@
void visit_start_struct
-(TV v, TObj OBJ, T1 ARG1, const char *name, T2 ARG2, TErr errp)
+(TV v, const char *name, TObj OBJ, T1 ARG1, T2 ARG2, TErr errp)
{ ... }

@@
type bool, TV, T1;
identifier ARG1;
@@
bool visit_optional
-(TV v, T1 ARG1, const char *name)
+(TV v, const char *name, T1 ARG1)
{ ... }

@@
type TV, TErr, TObj, T1;
identifier OBJ, ARG1;
@@
void visit_get_next_type
-(TV v, TObj OBJ, T1 ARG1, const char *name, TErr errp)
+(TV v, const char *name, TObj OBJ, T1 ARG1, TErr errp)
{ ... }

@@
type TV, TErr, TObj, T1, T2;
identifier OBJ, ARG1, ARG2;
@@
void visit_type_enum
-(TV v, TObj OBJ, T1 ARG1, T2 ARG2, const char *name, TErr errp)
+(TV v, const char *name, TObj OBJ, T1 ARG1, T2 ARG2, TErr errp)
{ ... }

@@
type TV, TErr, TObj;
identifier OBJ;
identifier VISIT_TYPE =~ "^visit_type_";
@@
void VISIT_TYPE
-(TV v, TObj OBJ, const char *name, TErr errp)
+(TV v, const char *name, TObj OBJ, TErr errp)
{ ... }

// Part 2: swap caller order
@@
expression V, NAME, OBJ, ARG1, ARG2, ERR;
identifier VISIT_TYPE =~ "^visit_type_";
@@
(
-visit_start_struct(V, OBJ, ARG1, NAME, ARG2, ERR)
+visit_start_struct(V, NAME, OBJ, ARG1, ARG2, ERR)
|
-visit_optional(V, ARG1, NAME)
+visit_optional(V, NAME, ARG1)
|
-visit_get_next_type(V, OBJ, ARG1, NAME, ERR)
+visit_get_next_type(V, NAME, OBJ, ARG1, ERR)
|
-visit_type_enum(V, OBJ, ARG1, ARG2, NAME, ERR)
+visit_type_enum(V, NAME, OBJ, ARG1, ARG2, ERR)
|
-VISIT_TYPE(V, OBJ, NAME, ERR)
+VISIT_TYPE(V, NAME, OBJ, ERR)
)

Backports commit 51e72bc1dd6ace6e91d675f41a1f09bd00ab8043 from qemu
2018-02-19 22:45:07 -05:00
Eric Blake 5b6f0cbdb7
qom: Use typedef for Visitor
No need to repeat 'struct Visitor' when we already have it in
typedefs.h. Omitting the redundant 'struct' also makes a later
patch easier to search for all object property callbacks that
are associated with a Visitor.

Backports commit 4fa45492c3387c0fa51e8e81160ac9a7814f44a2 from qemu
2018-02-19 22:26:47 -05:00
Eric Blake b978871f20
qapi: Don't cast Enum* to int*
C compilers are allowed to represent enums as a smaller type
than int, if all enum values fit in the smaller type. There
are even compiler flags that force the use of this smaller
representation, although using them changes the ABI of a
binary. Therefore, our generated code for visit_type_ENUM()
(for all qapi enums) was wrong for casting Enum* to int* when
calling visit_type_enum().

It appears that no one has been using compiler ABI switches
for qemu, because if they had, we are potentially dereferencing
beyond bounds or even risking a SIGBUS on platforms where
unaligned pointer dereferencing is fatal. But it is still
better to avoid the practice entirely, and just use the correct
types.

This matches the fix for alternate qapi types, done earlier in
commit 0426d53 "qapi: Simplify visiting of alternate types",
with generated code changing as:

| void visit_type_QType(Visitor *v, QType *obj, const char *name, Error **errp)
| {
|- visit_type_enum(v, (int *)obj, QType_lookup, "QType", name, errp);
|+ int value = *obj;
|+ visit_type_enum(v, &value, QType_lookup, "QType", name, errp);
|+ *obj = value;
| }

Backports commit 395a233f7c089f23e3c0d43ce34c709dc5acd7de from qemu
2018-02-19 22:24:19 -05:00
Eric Blake 7e83274012
qapi-visit: Kill unused visit_end_union()
The generated code can call visit_end_union() without having called
visit_start_union(). Example:

if (!*obj) {
goto out_obj;
}
visit_type_CpuInfoBase_fields(v, (CpuInfoBase **)obj, &err);
if (err) {
goto out_obj; // if we go from here...
}
if (!visit_start_union(v, !!(*obj)->u.data, &err) || err) {
goto out_obj;
}
switch ((*obj)->arch) {
[...]
}
out_obj:
// ... then *obj is true, and ...
error_propagate(errp, err);
err = NULL;
if (*obj) {
// we end up here
visit_end_union(v, !!(*obj)->u.data, &err);
}
error_propagate(errp, err);

Harmless only because no visitor implements end_union(). Clean it up
anyway, by deleting the function as useless.

Messed up since we have visit_end_union (commit cee2ded).

Backports commit 7c91aabd8964cfdf637f302c579c95401f21ce92 from qemu
2018-02-19 22:22:24 -05:00
Eric Blake 264748ad06
qapi: Track all failures between visit_start/stop
Inside the generated code between visit_start_struct() and
visit_end_struct(), we were blindly setting the error into
the caller's errp parameter. But a future patch to split
visit_end_struct() will require that we take action based
on whether an error has occurred, which requires us to track
all actions through a local err. Rewrite the visits to be
more in line with the other generated calls.

Generated code changes look like:

| visit_start_struct(v, (void **)obj, "Abort", name, sizeof(Abort), &err);
|- if (!err) {
|- if (*obj) {
|- visit_type_Abort_fields(v, obj, errp);
|- }
|- visit_end_struct(v, &err);
|+ if (err) {
|+ goto out;
| }
|+ if (!*obj) {
|+ goto out_obj;
|+ }
|+ visit_type_Abort_fields(v, obj, &err);
|+ error_propagate(errp, err);
|+ err = NULL;
|+out_obj:
|+ visit_end_struct(v, &err);
|+out:
| error_propagate(errp, err);
| }

Backports commit 92b09babc11b60458c28cfe37eaa314de50e6241 from qemu
2018-02-19 22:19:40 -05:00
Eric Blake 4f513b2070
qapi: Improve generated event use of qapi visitor
All other successful clients of visit_start_struct() were paired
with an unconditional visit_end_struct(); but the generated
code for events was relying on qmp_output_visitor_cleanup() to
work on an incomplete visit. Alter the code to guarantee that
the struct is completed, which will make a future patch to
split visit_end_struct() easier to reason about. While at it,
drop some assertions and comments that are not present in other
uses of the qmp output visitor, and pass NULL rather than "" as
the 'kind' parameter (matching most other uses where obj is NULL).

The changes to the generated code look like:

| qmp = qmp_event_build_dict("DEVICE_TRAY_MOVED");
|
| qov = qmp_output_visitor_new();
|- g_assert(qov);
|-
| v = qmp_output_get_visitor(qov);
|- g_assert(v);
|
|- /* Fake visit, as if all members are under a structure */
|- visit_start_struct(v, NULL, "", "DEVICE_TRAY_MOVED", 0, &err);
|+ visit_start_struct(v, NULL, NULL, "DEVICE_TRAY_MOVED", 0, &err);
| if (err) {
| goto out;
| }
| visit_type_str(v, (char **)&device, "device", &err);
| if (err) {
|- goto out;
|+ goto out_obj;
| }
| visit_type_bool(v, &tray_open, "tray-open", &err);
| if (err) {
|- goto out;
|+ goto out_obj;
| }
|- visit_end_struct(v, &err);
|+out_obj:
|+ visit_end_struct(v, err ? NULL : &err);
| if (err) {
| goto out;
| }
|
| obj = qmp_output_get_qobject(qov);
|- g_assert(obj != NULL);
|+ g_assert(obj);
|
| qdict_put_obj(qmp, "data", obj);
| emit(QAPI_EVENT_DEVICE_TRAY_MOVED, qmp, &err);

Note that the 'goto out_obj' with no intervening code before the
label, as well as the construct of 'err ? NULL : &err', are both
a bit unusual but also temporary; they get fixed in a later patch
that splits visit_end_struct() to drop its errp parameter by moving
some checking before the label. But until that time, this was the
simplest way to avoid the appearance of passing a possibly-set
error to visit_end_struct(), even though actual code inspection
shows that visit_end_struct() for a QMP output visitor will never
set an error.

Backports commit a16e3e5c5825c90887a863513916f93eeec16c55 from qemu
2018-02-19 22:18:31 -05:00
Eric Blake b847298d08
qapi: Drop dead parameter in gen_params()
Commit 5cdc8831 reworked gen_params() to be simpler, but forgot
to clean up a now-unused errp named argument.

No change to generated code.

Backports commit e408311546b633b232312450d9017f4db21df0dc from qemu
2018-02-19 22:16:16 -05:00
Markus Armbruster b2c9386111
qapi: Use Python 2.6 "except E as ..." syntax
PEP 8 calls for it, because it's forward compatible with Python 3.
Supported since Python 2.6, which we require (commit fec2103).

Backports commit 291928a80f39670929fcce222acd5e21d1434692 from qemu
2018-02-19 22:14:39 -05:00
Eric Blake f7d5b1c833
qapi: Detect base class loops
It should be fairly obvious that qapi base classes need to
form an acyclic graph, since QMP cannot specify the same
key more than once, while base classes are included as flat
members alongside other members added by the child. But the
old check_member_clash() parser function was not prepared to
check for this, and entered an infinite recursion (at least
until Python gives up, complaining about nesting too deep).

Now that check_member_clash() has been recently removed,
attempts at self-inheritance trigger an assertion failure
introduced by commit ac88219a. The obvious fix is to turn
the assertion into a conditional.

This patch includes both the tests (base-cycle-direct and
base-cycle-indirect) and the fix, since the .err file output
for the unfixed case is not useful (particularly when it was
warning about unbounded recursion, as that limit may be
platform-specific).

We don't need to worry about cycles in flat unions (neither
the base type nor the type of a variant can be a union) nor
in alternates (alternate branches cannot themselves be an
alternate). But if we later allow a union type as a variant,
we will still be okay, as QAPISchemaObjectTypeVariants.check()
triggers the same QAPISchemaObjectType.check() that will
detect any loops.

Likewise, we need not worry about the case of diamond
inheritance where the same class is used for a flat union base
class and one of its variants; either both uses will introduce
a collision in trying to insert the same member name twice, or
the shared type is empty and changes nothing.

Backports commit bac5429ccb4f41d421ec641b11f1852c8420fdb7 from qemu
2018-02-19 22:12:19 -05:00
Eric Blake 63f288263a
qapi: Move duplicate collision checks to schema check()
With the recent commit 'qapi: Detect collisions in C member
names', we have two different locations for detecting clashes -
one at parse time, and another at QAPISchema*.check() time.
Remove all of the ad hoc parser checks, and delete associated
code (for example, the global check_member_clash() method is
no longer needed).

Testing this showed that the test union-bad-branch wasn't adding
much: union-clash-branches also exposes the error message when
branches collide, and we've recently fixed things to avoid an
implicit collision with max. Likewise, the error for
enum-clash-member changes to report our new detection of
upper case in a value name, unless we modify the test to use
all lower case.

The wording of several error messages has changed, but the
change is generally an improvement rather than a regression.

No change to generated code.

Backports commit 01cfbaa4c36ecd9f1c7bcbad50c92758e1d147c4 from qemu
2018-02-19 22:11:28 -05:00
Eric Blake 514226002a
qapi: Enforce (or whitelist) case conventions on qapi members
We document that members of enums and objects should be
'lower-case', although we were not enforcing it. We have to
whitelist a few pre-existing entities that violate the norms.
Add three new tests to expose the new error message, each of
which first uses the whitelisted name 'UuidInfo' to prove the
whitelist works, then triggers the failure (this is the same
pattern used in the existing returns-whitelist.json test).

Note that by adding this check, we have effectively forbidden
an entity with a case-insensitive clash of member names, for
any entity that is not on the whitelist (although there is
still the possibility to clash via '-' vs. '_').

Not done here: a future patch should also add naming convention
support and whitelist exceptions for command, event, and type
names.

The additions to QAPISchemaMember.check_clash() check whether
info['name'] is in the whitelist (the top-most entity name at
the point 'info' tracks), rather than self.owner (the type,
possibly implicit, that directly owns the member), because it
is easier to maintain the whitelist by the names actually in
the user's .json file, rather than worrying about the names
of implicit types.

Backports commit 893e1f2c5170d54316f1dcf3fefae679175622fc from qemu
2018-02-19 22:09:45 -05:00
Eric Blake 2e1e2c4d51
qapi: Track enum values by QAPISchemaMember, not string
Rather than using just an array of strings, make enum.values be
an array of the new QAPISchemaMember type, and add a helper
member_names() method to get back at the original list of names.
Likewise, creating an enum requires wrapping strings, via a new
QAPISchema._make_enum_members() method. The benefit of wrapping
enum members in a QAPISchemaMember Python object is that we now
share the existing code for C name clash detection (although the
code is not yet active until a later commit removes the earlier
ad hoc parser checks).

In a related change, the QAPISchemaMember._pretty_owner() method
needs to learn about one more implicit type name: the generated
enum associated with a simple union.

In the interest of keeping the changes of this patch local to one
file, the visitor interface still passes just a list of names
rather than the full list of QAPISchemaMember instances. We may
want to revisit this in the future, if the consistency with
visit_object_type() is worth it.

Backports commit 93bda4dd461358b4fc05dfd8e2d6419cdd574789 from qemu
2018-02-19 22:07:17 -05:00
Eric Blake ff43b7446a
qapi: Prepare new QAPISchemaMember base class
We want to share some clash detection code between enum values
and object type members. To assist with that, split off part
of QAPISchemaObjectTypeMember into a new base class
QAPISchemaMember that tracks name, owner, and common clash
detection code; while the former keeps the additional fields
for type and optional flag.

Backports commit d44f9ac80c43e34b1522cde8829f0ab371f086ca from qemu
2018-02-19 22:04:41 -05:00
Eric Blake 994490d197
qapi: Shorter visits of optional fields
For less code, reflect the determined boolean value of an optional
visit back to the caller instead of making the caller read the
boolean after the fact.

The resulting generated code has the following diff:

|- visit_optional(v, &has_fdset_id, "fdset-id");
|- if (has_fdset_id) {
|+ if (visit_optional(v, &has_fdset_id, "fdset-id")) {
| visit_type_int(v, &fdset_id, "fdset-id", &err);
| if (err) {
| goto out;
| }
| }

Backports commit 29637a6ee913df8fcdf371426ee48956b945b618 from qemu
2018-02-19 22:03:23 -05:00
Eric Blake f3d2380f6d
qapi: Simplify visits of optional fields
None of the visitor callbacks would set an error when testing
if an optional field was present; make this part of the interface
contract by eliminating the errp argument.

The resulting generated code has a nice diff:

|- visit_optional(v, &has_fdset_id, "fdset-id", &err);
|- if (err) {
|- goto out;
|- }
|+ visit_optional(v, &has_fdset_id, "fdset-id");
| if (has_fdset_id) {
| visit_type_int(v, &fdset_id, "fdset-id", &err);
| if (err) {
| goto out;
| }
| }

Backports commit 5cdc8831a795fb8452d7e34f644202fd724e122a from qemu
2018-02-19 22:01:27 -05:00
Eric Blake 65d58b543e
qapi: Fix alternates that accept 'number' but not 'int'
The QMP input visitor allows integral values to be assigned by
promotion to a QTYPE_QFLOAT. However, when parsing an alternate,
we did not take this into account, such that an alternate that
accepts 'number' and some other type, but not 'int', would reject
integral values.

With this patch, we now have the following desirable table:

alternate has case selected for
'int' 'number' QTYPE_QINT QTYPE_QFLOAT
no no error error
no yes 'number' 'number'
yes no 'int' error
yes yes 'int' 'number'

While it is unlikely that we will ever use 'number' in an
alternate other than in the testsuite, it never hurts to be
more precise in what we allow.

Backports commit d00341af384665d259af475b14c96bb8414df415 from qemu
2018-02-19 21:58:10 -05:00
Lioncash a6b494dcae
qapi: Inline _make_implicit_tag()
Now that alternates no longer use an implicit tag, we can
inline _make_implicit_tag() into its one caller,
_def_union_type().

No change to generated code.

Backports commit 9d3f3494c5b941774e2c3e7639332d53bbe6f8be from qemu
2018-02-19 21:54:43 -05:00
Eric Blake ff1c8774ff
qapi-types: Drop unnedeed ._fwdefn
Previously, the generated code in qapi-types.c initialized all
enum lookup tables first, prior to any other definitions. But
there are no topological sorting requirements that mandate this
layout, so we can drop the QAPISchemaGenTypeVisitor._fwdefn
field and just generate all definitions in visitation order.

The generated code shows some churn due to reordering, but it
is still fairly straightforward to follow (all the deletions
occur in one hunk, and all the deleted lines are re-inserted
in the same order later in the same files, just spread across
multiple insertion points).

Backports commit 0b2e84ba774651656771ed697dee8825759dffa9 from qemu
2018-02-19 21:53:45 -05:00
Eric Blake 2ee6c960ee
qapi: Simplify visiting of alternate types
Previously, working with alternates required two lookup arrays
and some indirection: for type Foo, we created Foo_qtypes[]
which maps each qtype to a value of the generated FooKind enum,
then look up that value in FooKind_lookup[] like we do for other
union types.

This has a couple of subtle bugs. First, the generator was
creating a call with a parameter '(int *) &(*obj)->type' where
type is an enum type; this is unsafe if the compiler chooses
to store the enum type in a different size than int, where
assigning through the wrong size pointer can corrupt data or
cause a SIGBUS.

Related bug, not not fixed in this patch: qapi-visit.py's
gen_visit_enum() generates a cast of its enum * argument to
int *. Marked FIXME.

Second, since the values of the FooKind enum start at zero, all
entries of the Foo_qtypes[] array that were not explicitly
initialized will map to the same branch of the union as the
first member of the alternate, rather than triggering a desired
failure in visit_get_next_type(). Fortunately, the bug seldom
bites; the very next thing the input visitor does is try to
parse the incoming JSON with the wrong parser, which normally
fails; the output visitor is not used with a C struct in that
state, and the dealloc visitor has nothing to clean up (so
there is no leak).

However, the second bug IS observable in one case: parsing an
integer causes unusual behavior in an alternate that contains
at least a 'number' member but no 'int' member, because the
'number' parser accepts QTYPE_QINT in addition to the expected
QTYPE_QFLOAT (that is, since 'int' is not a member, the type
QTYPE_QINT accidentally maps to FooKind 0; if this enum value
is the 'number' branch the integer parses successfully, but if
the 'number' branch is not first, some other branch tries to
parse the integer and rejects it). A later patch will worry
about fixing alternates to always parse all inputs that a
non-alternate 'number' would accept, for now this is still
marked FIXME in the updated test-qmp-input-visitor.c, to
merely point out that new undesired behavior of 'ans' matches
the existing undesired behavior of 'asn'.

This patch fixes the default-initialization bug by deleting the
indirection, and modifying get_next_type() to directly assign a
QTypeCode parameter. This in turn fixes the type-casting bug,
as we are no longer casting a pointer to enum to a questionable
size. There is no longer a need to generate an implicit FooKind
enum associated with the alternate type (since the QMP wire
format never uses the stringized counterparts of the C union
member names). Since the updated visit_get_next_type() does not
know which qtypes are expected, the generated visitor is
modified to generate an error statement if an unexpected type is
encountered.

Callers now have to know the QTYPE_* mapping when looking at the
discriminator; but so far, only the testsuite was even using the
C struct of an alternate types. I considered the possibility of
keeping the internal enum FooKind, but initialized differently
than most generated arrays, as in:
typedef enum FooKind {
FOO_KIND_A = QTYPE_QDICT,
FOO_KIND_B = QTYPE_QINT,
} FooKind;
to create nicer aliases for knowing when to use foo->a or foo->b
when inspecting foo->type; but it turned out to add too much
complexity, especially without a client.

There is a user-visible side effect to this change, but I
consider it to be an improvement. Previously,
the invalid QMP command:
{"execute":"blockdev-add", "arguments":{"options":
{"driver":"raw", "id":"a", "file":true}}}
failed with:
{"error": {"class": "GenericError",
"desc": "Invalid parameter type for 'file', expected: QDict"}}
(visit_get_next_type() succeeded, and the error comes from the
visit_type_BlockdevOptions() expecting {}; there is no mention of
the fact that a string would also work). Now it fails with:
{"error": {"class": "GenericError",
"desc": "Invalid parameter type for 'file', expected: BlockdevRef"}}
(the error when the next type doesn't match any expected types for
the overall alternate).

Backports commit 0426d53c6530606bf7641b83f2b755fe61c280ee from qemu
2018-02-19 21:52:39 -05:00
Eric Blake e9666e4455
qapi: Convert QType into QAPI built-in enum type
What's more meta than using qapi to define qapi? :)

Convert QType into a full-fledged[*] builtin qapi enum type, so
that a subsequent patch can then use it as the discriminator
type of qapi alternate types. Fortunately, the judicious use of
'prefix' in the qapi definition avoids churn to the spelling of
the enum constants.

To avoid circular definitions, we have to flip the order of
inclusion between "qobject.h" vs. "qapi-types.h". Back in commit
28770e0, we had the latter include the former, so that we could
use 'QObject *' for our implementation of 'any'. But that usage
also works with only a forward declaration, whereas the
definition of QObject requires QType to be a complete type.

[*] The type has to be builtin, rather than declared in
qapi/common.json, because we want to use it for alternates even
when common.json is not included. But since it is the first
builtin enum type, we have to add special cases to qapi-types
and qapi-visit to only emit definitions once, even when two
qapi files are being compiled into the same binary (the way we
already handled builtin list types like 'intList'). We may
need to revisit how multiple qapi files share common types,
but that's a project for another day.

Backports commit 7264f5c50cc1be0f1406e3ebb45aedcca02f603a from qemu
2018-02-19 21:47:05 -05:00
Eric Blake 805c803298
qobject: Rename qtype_code to QType
The name QType matches our CODING_STYLE conventions for type names
in CamelCase. It also matches the fact that we are already naming
all the enum members with a prefix of QTYPE, not QTYPE_CODE. And
doing the rename will also make it easier for the next patch to use
QAPI for providing the enum, which also wants CamelCase type names.

Backports commit 1310a3d3bd9301ff5a825287638cfab24c2c6689 from qemu
2018-02-19 21:41:52 -05:00
Eric Blake cc1d62568e
qobject: Simplify QObject
The QObject hierarchy is small enough, and unlikely to grow further
(since we only use it to map to JSON and already cover all JSON
types), that we can simplify things by not tracking a separate
vtable, but just inline the code element of the vtable QType
directly into QObject (renamed to type), and track a separate array
of destroy functions. We can drop qnull_destroy_obj() in the
process.

The remaining QObject subclasses must export their destructor.

This also has the nice benefit of moving the typename 'QType'
out of the way, so that the next patch can repurpose it for a
nicer name for 'qtype_code'.

The various objects are still the same size (so no change in cache
line pressure), but now have less indirection (although I didn't
bother benchmarking to see if there is a noticeable speedup, as
we don't have hard evidence that this was in a performance hotspot
in the first place).

A future patch could drop the refcnt size to 32 bits for a smaller
struct on 64-bit architectures, if desired (we have limits on the
largest JSON that we are willing to parse, and will probably never
need to take full advantage of a 64-bit refcnt).

Backports commit 55e1819c509b3d9c10a54678b9c585bbda13889e from qemu
2018-02-19 21:37:48 -05:00
Markus Armbruster 105a6be9b0
qobject: Add a special null QObject
I'm going to fix the JSON parser to recognize null. The obvious
representation of JSON null as (QObject *)NULL doesn't work, because
the parser already uses it as an error value. Perhaps we should
change it to free NULL for null, but that's more than I can do right
now. Create a special null QObject instead.

The existing QDict, QList, and QString all represent something that
is a pointer in C and could therefore be associated with NULL. But
right now, all three of these sub-types are always non-null once
created, so the new null sentinel object is intentionally unrelated
to them.

Backports commit 481b002cc81ed7fc7b06e32e9d4d495d81739d14 from qemu
2018-02-19 21:25:58 -05:00
Eric Blake 0ae71ac202
qapi: Change munging of CamelCase enum values
When munging enum values, the fact that we were passing the entire
prefix + value through camel_to_upper() meant that enum values
spelled with CamelCase could be turned into CAMEL_CASE. However,
this provides a potential collision (both OneTwo and One-Two would
munge into ONE_TWO) for enum types, when the same two names are
valid side-by-side as QAPI member names. By changing the generation
of enum constants to always be prefix + '_' + c_name(value,
False).upper(), and ensuring that there are no case collisions (in
the next patches), we no longer have to worry about names that
would be distinct as QAPI members but collide as variant tag names,
without having to think about what munging the heuristics in
camel_to_upper() will actually perform on an enum value.

Making the change will affect enums that did not follow coding
conventions, using 'CamelCase' rather than desired 'lower-case'.

Thankfully, there are only two culprits: InputButton and ErrorClass.
We already tweaked ErrorClass to make it an alias of QapiErrorClass,
where only the alias needs changing rather than the whole tree. So
the bulk of this change is modifying INPUT_BUTTON_WHEEL_UP to the
new INPUT_BUTTON_WHEELUP (and likewise for WHEELDOWN). That part
of this commit may later need reverting if we rename the enum
constants from 'WheelUp' to 'wheel-up' as part of moving
x-input-send-event to a stable interface; but at least we have
documentation bread crumbs in place to remind us (commit 513e7cd),
and it matches the fact that SDL constants are also spelled
SDL_BUTTON_WHEELUP.

Backports commit d20a580bc0eac9d489884f6d2ed28105880532b6 from qemu
2018-02-19 20:40:15 -05:00
Eric Blake 1bda2b186b
qapi: Add alias for ErrorClass
The qapi enum ErrorClass is unusual that it uses 'CamelCase' names,
contrary to our documented convention of preferring 'lower-case'.
However, this enum is entrenched in the API; we cannot change
what strings QMP outputs. Meanwhile, we want to simplify how
c_enum_const() is used to generate enum constants, by moving away
from the heuristics of camel_to_upper() to a more straightforward
c_name(N).upper() - but doing so will rename all of the ErrorClass
constants and cause churn to all client files, where the new names
are aesthetically less pleasing (ERROR_CLASS_DEVICENOTFOUND looks
like we can't make up our minds on whether to break between words).

So as always in computer science, solve the problem by some more
indirection: rename the qapi type to QapiErrorClass, and add a
new enum ErrorClass in error.h whose members are aliases of the
qapi type, but with the spelling expected elsewhere in the tree.
Then, when c_enum_const() changes the munging, we only have to
adjust the one alias spot.

Backports commit f22a28b898322c01b0463a8b7ec551d72bc61a5b from qemu
2018-02-19 20:38:51 -05:00
Eric Blake 9a2b48ebc3
qapi: Remove obsolete tests for MAX collision
Now that we no longer collide with an implicit _MAX enum member,
we no longer need to reject it in the ad hoc parser, and can
remove several tests that are no longer needed.

Backports commit 04e0639d4e77b6d55491d396c8aa13929ee8ed9a from qemu
2018-02-19 20:36:35 -05:00
Eric Blake 9ca55f4ba5
qapi: Don't let implicit enum MAX member collide
Now that we guarantee the user doesn't have any enum values
beginning with a single underscore, we can use that for our
own purposes. Renaming ENUM_MAX to ENUM__MAX makes it obvious
that the sentinel is generated.

This patch was mostly generated by applying a temporary patch:

|diff --git a/scripts/qapi.py b/scripts/qapi.py
|index e6d014b..b862ec9 100644
|--- a/scripts/qapi.py
|+++ b/scripts/qapi.py
|@@ -1570,6 +1570,7 @@ const char *const %(c_name)s_lookup[] = {
| max_index = c_enum_const(name, 'MAX', prefix)
| ret += mcgen('''
| [%(max_index)s] = NULL,
|+// %(max_index)s
| };
| ''',
| max_index=max_index)

then running:

$ cat qapi-{types,event}.c tests/test-qapi-types.c |
sed -n 's,^// \(.*\)MAX,s|\1MAX|\1_MAX|g,p' > list
$ git grep -l _MAX | xargs sed -i -f list

The only things not generated are the changes in scripts/qapi.py.

Rejecting enum members named 'MAX' is now useless, and will be dropped
in the next patch.

Backports commit 7fb1cf1606c78c9d5b538f29176fd5a101726a9d from qemu
2018-02-19 20:34:53 -05:00
Eric Blake 00e596aad2
qapi: Tighten the regex on valid names
We already documented that qapi names should match specific
patterns (such as starting with a letter unless it was an enum
value or a downstream extension). Tighten that from a suggestion
into a hard requirement, which frees up names beginning with a
single underscore for qapi internal usage.

The tighter regex doesn't forbid everything insane that a user
could provide (for example, a user could name a type 'Foo-lookup'
to collide with the generated 'Foo_lookup[]' for an enum 'Foo'),
but does a good job at protecting the most obvious uses, and
also happens to reserve single leading underscore for later use.

The handling of enum values starting with a digit is tricky:
commit 9fb081e introduced a subtle bug by using c_name() on
a munged value, which would allow an enum to include the
member 'q-int' in spite of our reservation. Furthermore,
munging with a leading '_' would fail our tighter regex. So
fix it by only munging for leading digits (which are never
ticklish in c_name()) and by using a different prefix (I
picked 'D', although any letter should do).

Add new tests, reserved-member-underscore and reserved-enum-q,
to demonstrate the tighter checking.

Backports commit 59a92feedc6927e0e1ff87fdaccfb4dd42ad4c84 from qemu
2018-02-19 20:33:18 -05:00
Eric Blake a5cbe099d7
qapi: Remove dead visitor code
Commit cbc95538 removed unused start_handle() and end_handle(),
but forgot to remove their declarations.

Backports commit 7549457200ec3871ee827765f4d3bbc8d903b2ec from qemu
2018-02-19 20:32:00 -05:00
Eric Blake bacaf613b1
qapi: Fix c_name() munging
The method c_name() is supposed to do two different actions: munge
'-' into '_', and add a 'q_' prefix to ticklish names. But it did
these steps out of order, making it possible to submit input that
is not ticklish until after munging, where the output then lacked
the desired prefix.

The failure is exposed easily if you have a compiler that recognizes
C11 keywords, and try to name a member '_Thread-local', as it would
result in trying to compile the declaration 'uint64_t _Thread_local;'
which is not valid. However, this name violates our conventions
(ultimately, want to enforce that no qapi names start with single
underscore), so the test is slightly weaker by instead testing
'wchar-t'; the declaration 'uint64_t wchar_t;' is valid in C (where
wchar_t is only a typedef) but would fail with a C++ compiler (where
it is a keyword).

Fix things by reversing the order of actions within c_name().

Backports commit c43567c12042cf401b039bfc94a5f85e1cc1e796 from qemu
2018-02-19 20:31:08 -05:00
Eric Blake bc1e31663e
qapi: Detect collisions in C member names
Detect attempts to declare two object members that would result
in the same C member name, by keying the 'seen' dictionary off
of the C name rather than the qapi name. It also requires passing
info through the check_clash() methods.

This addresses a TODO and fixes the previously-broken
args-name-clash test. The resulting error message demonstrates
the utility of the .describe() method added previously. No change
to generated code.

Backports commit 27b60ab93bd1d5d8c85f009aac7a97ffd2c53c86 from qemu
2018-02-19 20:30:20 -05:00
Eric Blake e9647be986
qapi: Track owner of each object member
Future commits will migrate semantic checking away from parsing
and over to the various QAPISchema*.check() methods. But to
report an error message about an incorrect semantic use of a
member of an object type, it helps to know which type, command,
or event owns the member. In particular, when a member is
inherited from a base type, it is desirable to associate the
member name with the base type (and not the type calling
member.check()).

Rather than packing additional information into the seen array
passed to each member.check() (as in seen[m.name] = {'member':m,
'owner':type}), it is easier to have each member track the name
of the owner type in the first place (keeping things simpler
with the existing seen[m.name] = m). The new member.owner field
is set via a new set_owner() method, called when registering
the members and variants arrays with an object or variant type.
Track only a name, and not the actual type object, to avoid
creating a circular python reference chain.

Note that Variants.set_owner() method does not set the owner
for the tag_member field; this field is set earlier either as
part of an object's non-variant members, or explicitly by
alternates.

The source information is intended for human consumption in
error messages, and a new describe() method is added to access
the resulting information. For example, given the qapi:
{ 'command': 'foo', 'data': { 'string': 'str' } }
an implementation of visit_command() that calls
arg_type.members[0].describe()
will see "'string' (parameter of foo)".

To make the human-readable name of implicit types work without
duplicating efforts, the describe() method has to reverse the
name of implicit types, via the helper _pretty_owner().

No change to generated code.

Backports commit 88d4ef8b5cbf9d3336564b1d3ac7a91cbe4aee0e from qemu
2018-02-19 20:28:25 -05:00
Eric Blake 2f45c9ff99
qapi: Hoist tag collision check to Variants.check()
Checking that a given QAPISchemaObjectTypeVariant.name is a
member of the corresponding QAPISchemaEnumType of the owning
QAPISchemaObjectTypeVariants.tag_member ensures that there are
no collisions in the generated C union for those tag values
(since the enum itself should have no collisions).

However, ever since its introduction in f51d8c3d, this was the
only additional action of of Variant.check(), beyond calling
the superclass Member.check(). This forces a difference in
.check() signatures, just to pass the enum type down.

Simplify things by instead doing the tag name check as part of
Variants.check(), at which point we can rely on inheritance
instead of overriding Variant.check().

Backports commit 10565ca92a8d3f8a34559329acfbdb25a791b594 from qemu
2018-02-19 20:25:34 -05:00
Eric Blake 51b4313b34
qapi: Factor out QAPISchemaObjectType.check_clash()
Consolidate two common sequences of clash detection into a
new QAPISchemaObjectType.check_clash() helper method.

No change to generated code.

Backports commit c2183d2e62b6d9d66f80bc0bcf4fc7ec3c5d76d4 from qemu
2018-02-19 20:23:36 -05:00
Eric Blake e1f3c46a16
qapi: Check for QAPI collisions involving variant members
Right now, our ad hoc parser ensures that we cannot have a
flat union that introduces any members that would clash with
non-variant members inherited from the union's base type (see
flat-union-clash-member.json). We want QAPISchemaObjectType.check()
to make the same check, so we can later reduce some of the ad
hoc checks.

We already have a map 'seen' of all non-variant members. We
still need to check for collisions between each variant type's
members and the non-variant ones.

To know the variant type's members, we need to call
variant.type.check(). This also detects when a type contains
itself in a variant, exactly like the existing base.check()
detects when a type contains itself as a base. (Except that
we currently forbid anything but a struct as the type of a
variant, so we can't actually trigger this type of loop yet.)

Slight complication: an alternate's variant can have arbitrary
type, but only an object type's check() may be called outside
QAPISchema.check(). We could either skip the call for variants
of alternates, or skip it for non-object types. For now, do
the latter, because it's easier.

Then we call each variant member's check_clash() with the
appropriate 'seen' map. Since members of different variants
can't clash, we have to clone a fresh seen for each variant.
Wrap this in a new helper method
QAPISchemaObjectTypeVariants.check_clash().

Note that cloning 'seen' inside .check_clash() resembles
the one we just removed from .check() in 'qapi: Drop
obsolete tag value collision assertions'; the difference here is
that we are now checking for clashes among the qapi members of
the variant type, rather than for a single clash with the variant
tag name itself.

Note that, by construction, collisions can't actually happen for
simple unions: each variant's type is a wrapper with a single
member 'data', which will never collide with the only non-variant
member 'type'.

For alternates, there's nothing for a variant object type's
members to clash with, and therefore no need to call the new
variants.check_clash().

No change to generated code.

Backports commit b807a1e1e3796adaf3ece2f7b69ea5ee28468ff4 from qemu
2018-02-19 20:20:08 -05:00
Markus Armbruster fda436e0b2
qapi: Simplify QAPISchemaObjectTypeVariants.check()
Reduce the ugly flat union / simple union conditional by doing just
the essential work here, namely setting self.tag_member.
Move the rest to callers.

Backports commit 14ff84619c6bb9b729dbf8b127c1e4c56ed8c500 from qemu
2018-02-19 20:18:59 -05:00
Markus Armbruster 62f41569be
qapi: Factor out QAPISchemaObjectTypeMember.check_clash()
While there, stick in a TODO change key of seen from QAPI name to C
name. Can't do it right away, because it would fail the assertion for
tests/qapi-schema/args-has-clash.json.

Backports commit 577de12d22aba55f31fd68c5724411eb8592a4ca from qemu
2018-02-19 20:17:39 -05:00
Markus Armbruster 8b6a605685
qapi: Eliminate QAPISchemaObjectType.check() variable members
We can use seen.values() instead if we make it an OrderedDict.

Backports commit 23a4b2c6f19297cd067455c852b4874879594c13 from qemu
2018-02-19 20:15:45 -05:00
Markus Armbruster a0d6b16297
qapi: Fix up commit 7618b91's clash sanity checking change
This hunk

@@ -964,6 +965,7 @@ class QAPISchemaObjectType(QAPISchemaType):
members = []
seen = {}
for m in members:
+ assert c_name(m.name) not in seen
seen[m.name] = m
for m in self.local_members:
m.check(schema, members, seen)

is plainly broken.

Asserting the members inherited from base don't clash is somewhat
redundant, because self.base.check() just checked that. But it
doesn't hurt.

The idea to use c_name(m.name) instead of m.name for collision
checking is sound, because we need to catch clashes between the m.name
and between the c_name(m.name), and when two m.name clash, then their
c_name() also clash.

However, using c_name(m.name) instead of m.name in one of several
places doesn't work. See the very next line.

Keep the assertion, but drop the c_name() for now. A future commit
will bring it back.

Backports commit 08683353fc46b5d462199c9e8cff6f6c67f20f65 from qemu
2018-02-19 20:14:22 -05:00
Markus Armbruster f311d9c2d8
qapi: Clean up after previous commit
QAPISchemaObjectTypeVariants.check() parameter members and
QAPISchemaObjectTypeVariant.check() parameter seen are no longer used,
drop them.

Backports commit cdc5fa37eda2896d2b08f9215c963256eb859d3b from qemu
2018-02-19 20:13:58 -05:00
Markus Armbruster f246800df6
qapi: Simplify QAPISchemaObjectTypeMember.check()
QAPISchemaObjectTypeMember.check() currently does four things:

1. Compute self.type

2. Accumulate members in all_members

Only one caller cares: QAPISchemaObjectType.check() uses it to
compute self.members. The other callers pass a throw-away
accumulator.

3. Accumulate a map from names to members in seen

Only one caller cares: QAPISchemaObjectType.check() uses it to
compute its local variable seen, for self.variants.check(), which
uses it to compute self.variants.tag_member from
self.variants.tag_name. The other callers pass a throw-away
accumulator.

4. Check for collisions

This piggybacks on 3: before adding a new entry, we assert it's new.

Only one caller cares: QAPISchemaObjectType.check() uses it to
assert non-variant members don't clash.

Simplify QAPISchemaObjectType.check(): move 2.-4. to
QAPISchemaObjectType.check(), and drop parameters all_members and
seen.

Backports commit e564e2dd5963a75f32bbb90ac8181ba9dca2f1aa from qemu
2018-02-19 20:11:49 -05:00
Markus Armbruster 85ef080183
qapi: Drop obsolete tag value collision assertions
Union tag values can't clash with member names in generated C anymore
since commit e4ba22b, but QAPISchemaObjectTypeVariants.check() still
asserts they don't. Drop it.

Backports commit fff5f231d5f96e8521761efcd35a12479594059a from qemu
2018-02-19 20:07:52 -05:00
Eric Blake 5899d98959
qapi-types: Simplify gen_struct_field[s]
Simplify gen_struct_fields() back to a single iteration over a
list of fields (like it was prior to commit f87ab7f9), by moving
the generated comments to gen_object(). Then, inline
gen_struct_field() into its only caller.

Backports commit 7d9586f900a9043025866f84c096b1842b0bbbf6 from qemu
2018-02-19 20:06:38 -05:00
Eric Blake f637efea10
qapi-types: Consolidate gen_struct() and gen_union()
These two methods are now close enough that we can finally merge
them, relying on the fact that simple unions now provide a
reasonable local_members. Change gen_struct() to gen_object()
that handles all forms of QAPISchemaObjectType, and rename and
shrink gen_union() to gen_variants() to handle the portion of
gen_object() needed when variants are present.

gen_struct_fields() now has a single caller, so it no longer
needs an optional parameter; however, I did not choose to inline
it into the caller.

No difference to generated code.

Backports commit 570cd8d1194cf68f7c9948971e52e47f20855a77 from qemu
2018-02-19 20:04:26 -05:00
Eric Blake b7886e2d59
qapi: Track simple union tag in object.local_members
We were previously creating all unions with an empty list for
local_members. However, it will make it easier to unify struct
and union generation if we include the generated tag member in
local_members. That way, we can have a common code pattern:
visit the base (if any), visit the local members (if any), visit
the variants (if any). The local_members of a flat union
remains empty (because the discriminator is already visited as
part of the base). Then, by visiting tag_member.check() during
AlternateType.check(), we no longer need to call it during
Variants.check().

The various front end entities now exist as follows:
struct: optional base, optional local_members, no variants
simple union: no base, one-element local_members, variants with tag_member
from local_members
flat union: base, no local_members, variants with tag_member from base
alternate: no base, no local_members, variants

With the new local members, we require a bit of finesse to
avoid assertions in the clients.

No change to generated code.

Backports commit da34a9bd999d1be13954c699bbae0295cdaa3200 from qemu
2018-02-19 20:02:03 -05:00
Eric Blake ccb16c42a3
qapi: Test failure in middle of array parse
Our generated list visitors have the same problem as has been
mentioned elsewhere (see commit 2f52e20): they allocate data
even on failure. An upcoming patch will correct things to
provide saner guarantees, but first we need to expose the
behavior in the testsuite to ensure we aren't introducing any
memory usage bugs.

There are more test cases throughout the test-qmp-input-* tests
that already deal with partial allocation; a later commit will
clean up all visit_type_FOO(), without marking all of the tests
with FIXME at this time.

Backports commit dd5ee2c2d3e3a17647ddd9bfa97935b8cb5dfa40 from qemu
2018-02-19 19:31:50 -05:00
Eric Blake 0cb457056d
qapi: Simplify gen_struct_field()
Rather than having all callers pass a name, type, and optional
flag, have them instead pass a QAPISchemaObjectTypeMember which
already has all that information.

No change to generated code.

Backports commit 32bc6879beea0b0cac6196cb15a71d206401e96d from qemu
2018-02-19 19:30:26 -05:00
Eric Blake 61ad7b3824
qapi: Reserve 'u' member name
Now that we have separated union tag values from colliding with
non-variant C names, by naming the union 'u', we should reserve
this name for our use. Note that we want to forbid 'u' even in
a struct with no variants, because it is possible for a future
qemu release to extend QMP in a backwards-compatible manner while
converting from a struct to a flat union. Fortunately, no
existing clients were using this member name. If we ever find
the need for QMP to have a member 'u', we could at that time
relax things, perhaps by having c_name() munge the QMP member to
'q_u'.

Note that we cannot forbid 'u' everywhere (by adding the
rejection code to check_name()), because the existing QKeyCode
enum already uses it; therefore we only reserve it as a struct
type member name.

Backports commit 5e59baf90a72cd25d38a3134edc029f4f022da74 from qemu
2018-02-19 19:28:47 -05:00
Eric Blake a75c85afa0
qapi: Finish converting to new qapi union layout
We have two issues with our qapi union layout:
1) Even though the QMP wire format spells the tag 'type', the
C code spells it 'kind', requiring some hacks in the generator.
2) The C struct uses an anonymous union, which places all tag
values in the same namespace as all non-variant members. This
leads to spurious collisions if a tag value matches a non-variant
member's name.

This patch is the back end for a series that converts to a
saner qapi union layout. Now that all clients have been
converted to use 'type' and 'obj->u.value', we can drop the
temporary parallel support for 'kind' and 'obj->value'.

Given a simple union qapi type:

{ 'union':'Foo', 'data': { 'a':'int', 'b':'bool' } }

this is the overall effect, when compared to the state before
this series of patches:

| struct Foo {
|- FooKind kind;
|- union { /* union tag is @kind */
|+ FooKind type;
|+ union { /* union tag is @type */
| void *data;
| int64_t a;
| bool b;
|- };
|+ } u;
| };

The testsuite still contains some examples of artificial restrictions
(see flat-union-clash-type.json, for example) that are no longer
technically necessary, now that there is no longer a collision between
enum tag values and non-variant member names; but fixing this will be
done in later patches, in part because some further changes are required
to keep QAPISchema*.check() from asserting. Also, a later patch will
add a reservation for the member name 'u' to avoid a collision between a
user's non-variant names and our internal choice of C union name.

Note, however, that we do not rename the generated enum, which
is still 'FooKind'. A further patch could generate implicit
enums as 'FooType', but while the generator already reserved
the '*Kind' namespace (commit 4dc2e69), there are already QMP
constructs with '*Type' naming, which means changing our
reservation namespace would have lots of churn to C code to
deal with a forced name change.

Backports commit e4ba22b31943ab02373359555bd7bcd66442632f from qemu
2018-02-19 19:27:54 -05:00
Eric Blake a75ad0555f
qapi-visit: Convert to new qapi union layout
We have two issues with our qapi union layout:
1) Even though the QMP wire format spells the tag 'type', the
C code spells it 'kind', requiring some hacks in the generator.
2) The C struct uses an anonymous union, which places all tag
values in the same namespace as all non-variant members. This
leads to spurious collisions if a tag value matches a non-variant
member's name.

Make the conversion to the new layout for qapi-visit.py.

Generated code changes look like:

|@@ -4912,16 +4912,16 @@ void visit_type_MemoryDeviceInfo(Visitor
| if (!*obj) {
| goto out_obj;
| }
|- visit_type_MemoryDeviceInfoKind(v, &(*obj)->kind, "type", &err);
|+ visit_type_MemoryDeviceInfoKind(v, &(*obj)->type, "type", &err);
| if (err) {
| goto out_obj;
| }
|- if (!visit_start_union(v, !!(*obj)->data, &err) || err) {
|+ if (!visit_start_union(v, !!(*obj)->u.data, &err) || err) {
| goto out_obj;
| }
|- switch ((*obj)->kind) {
|+ switch ((*obj)->type) {
| case MEMORY_DEVICE_INFO_KIND_DIMM:
|- visit_type_PCDIMMDeviceInfo(v, &(*obj)->dimm, "data", &err);
|+ visit_type_PCDIMMDeviceInfo(v, &(*obj)->u.dimm, "data", &err);
| break;
| default:
| abort();
|@@ -4930,7 +4930,7 @@ out_obj:
| error_propagate(errp, err);
| err = NULL;
| if (*obj) {
|- visit_end_union(v, !!(*obj)->data, &err);
|+ visit_end_union(v, !!(*obj)->u.data, &err);
| }
| error_propagate(errp, err);
| err = NULL;

Backports commit 150d0564a4c626642897c748f7906260a13c14e1 from qemu
2018-02-19 19:25:20 -05:00
Eric Blake 75f1b8632e
qapi: Start converting to new qapi union layout
We have two issues with our qapi union layout:
1) Even though the QMP wire format spells the tag 'type', the
C code spells it 'kind', requiring some hacks in the generator.
2) The C struct uses an anonymous union, which places all tag
values in the same namespace as all non-variant members. This
leads to spurious collisions if a tag value matches a non-variant
member's name.

This patch is the front end for a series that converts to a
saner qapi union layout. By the end of the series, we will no
longer have the type/kind mismatch, and all tag values will be
under a named union, which requires clients to access
'obj->u.value' instead of 'obj->value'. But since the
conversion touches a number of files, it is easiest if we
temporarily support BOTH layouts simultaneously.

Given a simple union qapi type:

{ 'union':'Foo', 'data': { 'a':'int', 'b':'bool' } }

make the following changes in generated qapi-types.h:

| struct Foo {
|- FooKind kind;
|- union { /* union tag is @kind */
|+ union {
|+ FooKind kind;
|+ FooKind type;
|+ };
|+ union { /* union tag is @type */
| void *data;
| int64_t a;
| bool b;
|+ union { /* union tag is @type */
|+ void *data;
|+ int64_t a;
|+ bool b;
|+ } u;
| };
| };

Flat unions do not need the anonymous union for the tag member,
as we already fixed that to use the member name instead of 'kind'
back in commit 0f61af3e.

One additional change is needed in qapi.py: check_union() now
needs to check for collisions with 'type' in addition to those
with 'kind'.

Later, when the conversions are complete, we will remove the
duplication hacks, and also drop the check_union() restrictions.

Note, however, that we do not rename the generated enum, which
is still 'FooKind'. A further patch could generate implicit
enums as 'FooType', but while the generator already reserved
the '*Kind' namespace (commit 4dc2e69), there are already QMP
constructs with '*Type' naming, which means changing our
reservation namespace would have lots of churn to C code to
deal with a forced name change.

Backports commit f51d8fab44b231aa299d8de24cfdf9ba41ef4a21 from qemu
2018-02-19 19:21:41 -05:00
Eric Blake 7be2bc687d
qapi-visit: Remove redundant functions for flat union base
The code for visiting the base class of a child struct created
visit_type_Base_fields() which covers all fields of Base; while
the code for visiting the base class of a flat union created
visit_type_Union_fields() covering all fields of the base
except the discriminator. But since the base class includes
the discriminator of a flat union, we can just visit the entire
base, without needing a separate visit of the discriminator.
Not only is consistently visiting all fields easier to
understand, it lets us share code.

The generated code in qapi-visit.c loses several now-unused
visit_type_UNION_fields(), along with changes like:

|@@ -1654,11 +1557,7 @@ void visit_type_BlockdevOptions(Visitor
| if (!*obj) {
| goto out_obj;
| }
|- visit_type_BlockdevOptions_fields(v, obj, &err);
|- if (err) {
|- goto out_obj;
|- }
|- visit_type_BlockdevDriver(v, &(*obj)->driver, "driver", &err);
|+ visit_type_BlockdevOptionsBase_fields(v, (BlockdevOptionsBase **)obj, &err);
| if (err) {
| goto out_obj;
| }

and forward declarations where needed. Note that the cast of obj
to BASE ** is necessary to call visit_type_BASE_fields() (and we
can't use our upcast wrappers, because those work on pointers while
we have a pointer-to-pointer).

Backports commit 5c5e51a05b567fd48fb155d94ca6f7679dd0d478 from qemu
2018-02-19 19:18:53 -05:00
Eric Blake 6a9cbbeaed
qapi: Unbox base members
Rather than storing a base class as a pointer to a box, just
store the fields of that base class in the same order, so that
a child struct can be directly cast to its parent. This gives
less malloc overhead, less pointer dereferencing, and even less
generated code. Compare to the earlier commit 1e6c1616a "qapi:
Generate a nicer struct for flat unions" (although that patch
had fewer places to change, as less of qemu was directly using
qapi structs for flat unions). It also allows us to turn on
automatic type-safe wrappers for upcasting to the base class
of a struct.

Changes to the generated code look like this in qapi-types.h:

| struct SpiceChannel {
|- SpiceBasicInfo *base;
|+ /* Members inherited from SpiceBasicInfo: */
|+ char *host;
|+ char *port;
|+ NetworkAddressFamily family;
|+ /* Own members: */
| int64_t connection_id;

as well as additional upcast functions like qapi_SpiceChannel_base().
Meanwhile, changes to qapi-visit.c look like:

| static void visit_type_SpiceChannel_fields(Visitor *v, SpiceChannel **obj, Error **errp)
| {
| Error *err = NULL;
|
|- visit_type_implicit_SpiceBasicInfo(v, &(*obj)->base, &err);
|+ visit_type_SpiceBasicInfo_fields(v, (SpiceBasicInfo **)obj, &err);
| if (err) {

(the cast is necessary, since our upcast wrappers only deal with a
single pointer, not pointer-to-pointer); plus the wholesale
elimination of some now-unused visit_type_implicit_FOO() functions.

Without boxing, the corner case of one empty struct having
another empty struct as its base type now requires inserting a
dummy member (previously, the 'Base *base' member sufficed).

And now that we no longer consume a 'base' member in the generated
C struct, we can delete the former negative struct-base-clash-base
test.

Backports commit ddf21908961073199f3d186204da4810f2ea150b from qemu
2018-02-19 19:17:02 -05:00
Eric Blake 97c801d6a1
qapi: Prefer typesafe upcasts to qapi base classes
A previous patch (commit 1e6c1616) made it possible to
directly cast from a qapi flat union type to its base type.
However, it requires the use of a C cast, which turns off
compiler type-safety checks. Fortunately, no such casts
exist, just yet.

Regardless, add inline type-safe wrappers named
qapi_FOO_base() for any union type FOO that has a base,
which can be used for a safer upcast, and enhance the
testsuite to cover the new functionality.

A future patch will extend the upcast support to structs,
where such conversions do exist already.

Note that C makes const-correct upcasts annoying because
it lacks overloads; these functions cast away const so that
they can accept user pointers whether const or not, and the
result in turn can be assigned to normal or const pointers.
Alternatively, this could have been done with macros, but
type-safe macros are hairy, and not worthwhile here.

This patch just adds upcasts. None of our code needed to
downcast from a base qapi class to a child. Also, in the
case of grandchildren (such as BlockdevOptionsQcow2), the
caller will need to call two functions to get to the inner
base (although it wouldn't be too hard to generate a
qapi_FOO_base_base() if desired). If a user changes qapi
to alter the base class hierarchy, such as going from
'A -> C' to 'A -> B -> C', it will change the type of
'qapi_C_base()', and the compiler will point out the places
that are affected by the new base.

One alternative was proposed, but was deemed too ugly to use
in practice: the generators could output redundant
information using anonymous types:
| struct Child {
| union {
| struct {
| Type1 parent_member1;
| Type2 parent_member2;
| };
| Parent base;
| };
| };
With that ugly proposal, for a given qapi type, obj->member
and obj->base.member would refer to the same storage; allowing
convenience in working with members without needing 'base.'
allowing typesafe upcast without needing a C cast by accessing
'&obj->base', and allowing downcasts from the parent back to
the child possible through container_of(obj, Child, base).

Backports commit 30594fe1cd4355626e73b80645428105d0df3cf6 from qemu
2018-02-19 19:14:03 -05:00
Eric Blake ac0ee0286c
qapi-types: Refactor base fields output
Move code from gen_union() into gen_struct_fields() in order for
a later patch to share code when enumerating inherited fields
for struct types.

No change to generated code.

Backports commit f87ab7f9bd956250c48b5c6e9b607b537fd21543 from qemu
2018-02-19 19:13:01 -05:00
Eric Blake 61e59c4c62
qapi-visit: Split off visit_type_FOO_fields forward decl
We generate a static visit_type_FOO_fields() for every type
FOO. However, sometimes we need a forward declaration. Split
the code to generate the forward declaration out of
gen_visit_implicit_struct() into a new gen_visit_fields_decl(),
and also prepare for a forward declaration to be emitted
during gen_visit_struct(), so that a future patch can switch
from using visit_type_FOO_implicit() to the simpler
visit_type_FOO_fields() as part of unboxing the base class
of a struct.

No change to generated code.

Backports commit d02cf37766ba3cf918d7085aa7848c9dc05fd11a from qemu
2018-02-19 19:11:33 -05:00
Eric Blake 1f11f92a80
qapi: Reserve 'q_*' and 'has_*' member names
c_name() produces names starting with 'q_' when protecting a
dictionary member name that would fail to directly compile, but
in doing so can cause clashes with any member name already
beginning with 'q-' or 'q_'. Likewise, we create a C name 'has_'
for any optional member that can clash with any member name
beginning with 'has-' or 'has_'.

Technically, rather than blindly reserving the namespace,
we could try to complain about user names only when an actual
collision occurs, or even teach c_name() how to munge names
to avoid collisions. But it is not trivial, especially when
collisions can occur across multiple types (such as via
inheritance or flat unions). Besides, no existing .json
files are trying to use these names. So it's easier to just
outright forbid the potential for collision. We can always
relax things in the future if a real need arises for QMP to
express member names that have been forbidden here.

'has_' only has to be reserved for struct/union member names,
while 'q_' is reserved everywhere (matching the fact that
only members can be optional, while we use c_name() for munging
both members and entities). Note that we could relax 'q_'
restrictions on entities independently from member names; for
example, c_name('qmp_' + 'unix') would result in a different
function name than our current 'qmp_' + c_name('unix').

Update and add tests to cover the new error messages.

Backports commit 9fb081e0b98409556d023c7193eeb68947cd1211 from qemu
2018-02-19 19:09:17 -05:00
Eric Blake b9f93dd0e8
qapi: Reserve '*List' type names for list types
Type names ending in 'List' can clash with qapi list types in
generated C. We don't currently use such names. It is easier to
outlaw them now than to worry about how to resolve such a clash
in the future. For precedence, see commit 4dc2e69, which did the
same for names ending in 'Kind' versus implicit enum types for
qapi unions.

Update the testsuite to match.

Backports commit 255960dd374d4497d6ea537305f1b0d8a3433789 from qemu
2018-02-19 19:08:12 -05:00
Eric Blake 017baefb66
qapi: More robust conditions for when labels are needed
We were using regular expressions to see if ret included
any earlier text that emitted a 'goto out;' line, to decide
whether we needed to output an 'out:' label. But this is
fragile, if the ret text can possibly combine more than one
generated function body, where the first function used a
goto but the second does not. Change the code to just check
for the known conditions which cause an error check to be
needed. Besides, it's slightly more efficient to use plain
checks than regular expression searching.

No change to generated code.

Backports commit f9e6102b48f21e464a847a858a456c521e7a83e5 from qemu
2018-02-19 19:07:03 -05:00
Eric Blake 7a4feccf64
qapi: More idiomatic string operations
Rather than slicing the end of a string, we can use python's
endswith(). And rather than creating a set of characters,
we can search for a character within a string.

Backports commit 8712fa5333ad348da20034b717dd814219d1ec11 from qemu
2018-02-19 19:06:20 -05:00
Eric Blake 5e62ed79f9
qapi: Track location that created an implicit type
A future patch will move some error checking from the parser
to the various QAPISchema*.check() methods, which run only
after parsing completes. It will thus be possible to create
a python instance representing an implicit QAPI type that
parses fine but will fail validation during check(). Since
all errors have to have an associated 'info' location, we
need a location to be associated with those implicit types.
The intuitive info to use is the location of the enclosing
entity that caused the creation of the implicit type.

Note that we do not anticipate builtin types being used in
an error message (as they are not part of the user's QAPI
input, the user can't cause a semantic error in their
behavior), so we exempt those types from requiring info, by
setting a flag to track the completion of _def_predefineds(),
and tracking that flag in _def_entity().

No change to the generated code.

Backports commit 99df5289d8c7ebf373c3570d8fba3f3a73360281 from qemu
2018-02-19 19:04:41 -05:00
Eric Blake 738fd1e5ad
qapi: Create simple union type member earlier
For simple unions, we were creating the implicit 'type' tag
member during the QAPISchemaObjectTypeVariants constructor.
This is different from every other implicit QAPISchemaEntity
object, which get created by QAPISchema methods. Hoist the
creation to the caller (renaming _make_tag_enum() to
_make_implicit_tag()), and pass the entity rather than the
string name, so that we have the nice property that no
entities are created as a side effect within a different
entity. A later patch will then have an easier time of
associating location info with each entity creation.

No change to generated code.

Backports commit 46292ba75c515baf733df18644052b2ce9492728 from qemu
2018-02-19 18:57:56 -05:00
Eric Blake b9b76f9b4b
qapi: Lazy creation of array types
Commit ac88219a had several TODO markers about whether we needed
to automatically create the corresponding array type alongside
any other type. It turns out that most of the time, we don't!

There are a few exceptions: 1) We have a few situations where we
use an array type in internal code but do not expose that type
through QMP; fix it by declaring a dummy type that forces the
generator to see that we want to use the array type.

2) The builtin arrays (such as intList for QAPI ['int']) must
always be generated, because of the way our QAPI_TYPES_BUILTIN
compile guard works: we have situations (at the very least
tests/test-qmp-output-visitor.c) that include both top-level
"qapi-types.h" (via "error.h") and a secondary
"test-qapi-types.h". If we were to only emit the builtin types
when used locally, then the first .h file would not include all
types, but the second .h does not declare anything at all because
the first .h set QAPI_TYPES_BUILTIN, and we would end up with
compilation error due to things like unknown type 'int8List'.

Actually, we may need to revisit how we do type guards, and
change from a single QAPI_TYPES_BUILTIN over to a different
usage pattern that does one #ifdef per qapi type - right now,
the only types that are declared multiple times between two qapi
.json files for inclusion by a single .c file happen to be the
builtin arrays. But now that we have QAPI 'include' statements,
it is logical to assume that we will soon reach a point where
we want to reuse non-builtin types (yes, I'm thinking about what
it will take to add introspection to QGA, where we will want to
reuse the SchemaInfo type and friends). One #ifdef per type
will help ensure that generating the same qapi type into more
than one qapi-types.h won't cause collisions when both are
included in the same .c file; but we also have to solve how to
avoid creating duplicate qapi-types.c entry points. So that
is a problem left for another day.

Generated code for qapi-types and qapi-visit is drastically
reduced; less than a third of the arrays that were blindly
created were actually needed (a quick grep shows we dropped
from 219 to 69 *List types), and the .o files lost more than
30% of their bulk. [For best results, diff the generated
files with 'git diff --patience --no-index pre post'.]

Interestingly, the introspection output is unchanged - this is
because we already cull all types that are not indirectly
reachable from a command or event, so introspection was already
using only a subset of array types. The subset of types
introspected is now a much larger percentage of the overall set
of array types emitted in qapi-types.h (since the larger set
shrunk), but still not 100% (evidence that the array types
emitted for our new Dummy structs, and the new struct itself,
don't affect QMP).

Backports commit 9f08c8ec73878122ad4b061ed334f0437afaaa32 from qemu
2018-02-19 18:55:35 -05:00
Eric Blake dc65960e1f
qapi: Don't use info as witness of implicit object type
A future patch will enable error reporting from the various
QAPISchema*.check() methods. But to report an error related
to an implicit type, we'll need to associate a location with
the type (the same location as the top-level entity that is
causing the creation of the implicit type), and once we do
that, keying off of whether foo.info exists is no longer a
viable way to determine if foo is an implicit type.

Instead, add an is_implicit() method to QAPISchemaEntity, and use it.
It can be overridden later for ObjectType and EnumType, when implicit
instances of those classes gain info.

Backports commit 49823c4b4304a3e4aa5d67e089946b12d6a52d64 from qemu
2018-02-19 18:53:06 -05:00
Eric Blake 3d11f7173d
qapi: Prepare for errors during check()
The next few patches will start migrating error checking from
ad hoc parse methods into the QAPISchema*.check() methods. But
for an error message to display, we first have to fix the
overall 'try' to catch those errors. We also want to enable a
few more assertions, such as making sure every attempt to
raise a semantic error is passed a valid location info, or that
various preconditions hold.

The general approach for moving error checking will then be to
relax an assertion into an if that raises an exception if the
condition does not hold, and removing the counterpart ad hoc
check done during the parse phase.

Backports commit 7618b91ff80ec42b84b29be24d8ef53ddb377110 from qemu
2018-02-19 18:50:23 -05:00
Eric Blake 9d0c5746ff
qapi: Use predicate callback to determine visit filtering
Previously, qapi-types and qapi-visit filtered out implicit
objects during visit_object_type() by using 'info' (works since
implicit objects do not [yet] have associated info); meanwhile
qapi-introspect filtered out all schema types on the first pass
by returning a python type from visit_begin(), which was then
used at a distance in QAPISchema.visit() to do the filtering.

Rather than keeping these ad hoc approaches, add a new visitor
callback visit_needed() which returns False to skip a given
entity, and which defaults to True unless overridden. Use the
new mechanism to simplify all three filtering visitors.

No change to the generated code.

Backports commit 25a0d9c977c2f5db914b0a1619759fd77d97b016 from qemu
2018-02-19 18:49:08 -05:00
Eric Blake f371fa9105
qapi: Simplify gen_visit_fields() error handling
Since we have consolidated all generated code to use 'err' as
the name of the local variable for error detection, we can
simplify the decision on whether to skip error detection (useful
for deallocation paths) to be a boolean.

Backports commit 18bdbc3ac8b477e160d56aa6ecd6942495ce44d0 from qemu
2018-02-19 18:45:05 -05:00
Eric Blake 4ca10929a7
qapi: Share gen_visit_fields()
Consolidate the code between visit, command marshalling, and
event generation that iterates over the members of a struct.
It reduces code duplication in the generator, so that a future
patch can reduce the size of generated code while touching only
one instead of three locations.

There are no changes to the generated marshal code.

The visitor code becomes slightly more verbose, but remains
semantically equivalent, and is actually easier to read as
it follows a more common idiom:

| visit_optional(v, &(*obj)->has_device, "device", &err);
|- if (!err && (*obj)->has_device) {
|- visit_type_str(v, &(*obj)->device, "device", &err);
|- }
| if (err) {
| goto out;
| }
|+ if ((*obj)->has_device) {
|+ visit_type_str(v, &(*obj)->device, "device", &err);
|+ if (err) {
|+ goto out;
|+ }
|+ }

The event code becomes slightly more verbose, but this is
arguably a bug fix: although the visitors are not well
documented, use of an optional member should not be attempted
unless guarded by a prior call to visit_optional(). Works only
because the output qmp visitor has a no-op visit_optional():

|+ visit_optional(v, &has_offset, "offset", &err);
|+ if (err) {
|+ goto out;
|+ }
| if (has_offset) {
| visit_type_int(v, &offset, "offset", &err);

Backports commit 82ca8e469666b169ccf818a0e36136aee97d7db0 from qemu
2018-02-19 18:41:41 -05:00
Eric Blake 13b3a6c92f
qapi: Consistent generated code: minimize push_indent() usage
We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.
This is one patch of a series to clean up these differences.

This patch reduces the number of push_indent()/pop_indent() pairs
so that generated code is typically already at its natural output
indentation in the python files. It is easier to reason about
generated code if the reader does not have to track how much
spacing will be inserted alongside the code, and moreso when all
of the generators use the same patterns (qapi-type and qapi-event
were already using in-place indentation).

Arguably, the resulting python may be a bit harder to read with C
code at the same indentation as python; on the other hand, not
having to think about push_indent() is a win, and most decent
editors provide syntax highlighting that makes it easier to
visually distinguish python code from string literals that will
become C code.

There is no change to the generated output.

Backports commit 05372f708a8cb3556e4d67458de79417dadf241f from qemu
2018-02-19 18:38:48 -05:00
Eric Blake ec89e19b30
qapi: Consistent generated code: prefer common indentation
We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.
This is one patch of a series to clean up these differences.

This patch adjusts gen_visit_union() to use the same indentation
as other functions, namely, by jumping early to the error label
if the object was not set rather than placing the rest of the
body inside an if for when it is set.

No change in semantics to the generated code.

Backports commit e36c714e6aad7c9266132350833e2f263f6d8874 from qemu
2018-02-19 18:26:14 -05:00
Eric Blake 53c2c709af
qapi: Consistent generated code: prefer common labels
We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.
This is one patch of a series to clean up these differences.

This patch names the goto labels 'out' (not 'clean') and 'out_obj'
(not 'out_end'). Additionally, the generator was inconsistent on
whether labels had a leading space [our HACKING is silent; while
emacs 'gnu' style adds the space to avoid littering column 1].
For minimal churn, prefer no leading space; this also matches
the style that is more prevalent in current qemu.git.

No change in semantics to the generated code.

Backports commit f782399cb4fa3fc4182cb046817f65a6db92ab07 from qemu
2018-02-19 18:23:15 -05:00
Eric Blake 4e9c5e4d52
qapi: Consistent generated code: prefer visitor 'v'
We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.
This is one patch of a series to clean up these differences.

This patch names the local visitor variable 'v' rather than 'm'.
Related objects, such as 'QapiDeallocVisitor', are also named by
their initials instead of an unrelated leading m.

No change in semantics to the generated code.

Backports commit f8b7f1a8eafa9f565ebecfe409e8741d38cd786b from qemu
2018-02-19 18:21:53 -05:00
Eric Blake bc8a7ae5f9
qapi: Consistent generated code: prefer error 'err'
We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.
This is one patch of a series to clean up these differences.

This patch consistently names the local error variable 'err' rather
than 'local_err'.

No change in semantics to the generated code.

Backports commit 2a0f50e8d973b01eda4c63bac4a5c79ea0f584ef from qemu
2018-02-19 18:15:10 -05:00
Eric Blake 4294815ee3
qapi: Reuse code for flat union base validation
Rather than open-code the check for a valid base type, we
should reuse the common functionality. This allows for
consistent error messages, and also makes it easier for a
later patch to turn on support for inline anonymous base
structures.

Test flat-union-inline is updated to test only one feature
(anonymous branch dictionaries), which can be implemented
independently (test flat-union-bad-base already covers the
idea of an anonymous base dictionary).

Backports commit 376863ef4895ae709aadb6f26365a5973310ef09 from qemu
2018-02-19 18:14:53 -05:00
Eric Blake c09db972fe
qapi: Avoid assertion failure on union 'type' collision
The previous commit added two tests that triggered an assertion
failure. It's fairly straightforward to avoid the failure by
just outright forbidding the collision between a union's tag
values and its discriminator name (including the implicit name
'kind' supplied for simple unions [*]). Ultimately, we'd like
to move the collision detection into QAPISchema*.check(), but
for now it is easier just to enhance the existing checks.

[*] Of course, down the road, we have plans to rename the simple
union tag name to 'type' to match the QMP wire name, but the
idea of the collision will still be present even then.

Technically, we could avoid the collision by naming the C union
members representing each enum value as '_case_value' rather
than 'value'; but until we have an actual qapi client (and not
just our testsuite) that has a legitimate reason to match a
case label to the name of a QMP key and needs the name munging
to satisfy the compiler, it's easier to just reject the qapi
as invalid.

Backports commit 7b2a5c2f9a52c4a08630fa741052f03fe5d3cc8a from qemu
2018-02-19 18:09:13 -05:00
Eric Blake 8fce54a867
qapi: Clean up qapi.py per pep8
Silence pep8, and make pylint a bit happier. Just style cleanups,
plus killing a useless comment in camel_to_upper(); no semantic
changes.

Backports commit 437db2549be383e52acad6cd4bf2862e98fdfc93 from qemu
2018-02-19 18:07:55 -05:00
Eric Blake 07f0fa3ee9
qapi: Invoke exception superclass initializer
pylint recommends that every exception class should explicitly
invoke the superclass __init__, even though things seem to work
fine without it.

Backports commit 59b00542659c8947f9d4e8c28d2d528ab3ab61a5 from qemu
2018-02-19 17:57:21 -05:00
Eric Blake de2b67e528
qapi: Improve 'include' error message
Use of '"...%s" % include' to print non-strings can lead to
ugly messages, such as this (if the .json change is applied
without the qapi.py change):
 Expected a file name (string), got: OrderedDict()

Better is to just omit the actual non-string value in the
message.

Backports commit 7408fb67c0f9403f6e40aecf97cf798fc14e2cd8 from qemu
2018-02-19 17:56:17 -05:00
Markus Armbruster 02e411f666
qapi: New QMP command query-qmp-schema for QMP introspection
qapi/introspect.json defines the introspection schema. It's designed
for QMP introspection, but should do for similar uses, such as QGA.

The introspection schema does not reflect all the rules and
restrictions that apply to QAPI schemata. A valid QAPI schema has an
introspection value conforming to the introspection schema, but the
converse is not true.

Introspection lowers away a number of schema details, and makes
implicit things explicit:

* The built-in types are declared with their JSON type.

All integer types are mapped to 'int', because how many bits we use
internally is an implementation detail. It could be pressed into
external interface service as very approximate range information,
but that's a bad idea. If we need range information, we better do
it properly.

* Implicit type definitions are made explicit, and given
auto-generated names:

- Array types, named by appending "List" to the name of their
element type, like in generated C.

- The enumeration types implicitly defined by simple union types,
named by appending "Kind" to the name of their simple union type,
like in generated C.

- Types that don't occur in generated C. Their names start with ':'
so they don't clash with the user's names.

* All type references are by name.

* The struct and union types are generalized into an object type.

* Base types are flattened.

* Commands take a single argument and return a single result.

Dictionary argument or list result is an implicit type definition.

The empty object type is used when a command takes no arguments or
produces no results.

The argument is always of object type, but the introspection schema
doesn't reflect that.

The 'gen': false directive is omitted as implementation detail.

The 'success-response' directive is omitted as well for now, even
though it's not an implementation detail, because it's not used by
QMP.

* Events carry a single data value.

Implicit type definition and empty object type use, just like for
commands.

The value is of object type, but the introspection schema doesn't
reflect that.

* Types not used by commands or events are omitted.

Indirect use counts as use.

* Optional members have a default, which can only be null right now

Instead of a mandatory "optional" flag, we have an optional default.
No default means mandatory, default null means optional without
default value. Non-null is available for optional with default
(possible future extension).

* Clients should *not* look up types by name, because type names are
not ABI. Look up the command or event you're interested in, then
follow the references.

TODO Should we hide the type names to eliminate the temptation?

New generator scripts/qapi-introspect.py computes an introspection
value for its input, and generates a C variable holding it.

It can generate awfully long lines. Marked TODO.

A new test-qmp-input-visitor test case feeds its result for both
tests/qapi-schema/qapi-schema-test.json and qapi-schema.json to a
QmpInputVisitor to verify it actually conforms to the schema.

New QMP command query-qmp-schema takes its return value from that
variable. Its reply is some 85KiBytes for me right now.

If this turns out to be too much, we have a couple of options:

* We can use shorter names in the JSON. Not the QMP style.

* Optionally return the sub-schema for commands and events given as
arguments.

Right now qmp_query_schema() sends the string literal computed by
qmp-introspect.py. To compute sub-schema at run time, we'd have to
duplicate parts of qapi-introspect.py in C. Unattractive.

* Let clients cache the output of query-qmp-schema.

It changes only on QEMU upgrades, i.e. rarely. Provide a command
query-qmp-schema-hash. Clients can have a cache indexed by hash,
and re-query the schema only when they don't have it cached. Even
simpler: put the hash in the QMP greeting.

Backports commit 39a181581650f4d50f4445bc6276d9716cece050 from qemu
2018-02-19 17:54:03 -05:00