On the one hand, we have already qemu_get_ram_block() whose function
is similar. On the other hand, we can directly use mr->ram_block but
searching RAMblock by ram_addr which is a kind of waste.
Backports commit fa53a0e53efdc7002497ea4a76aacf6cceb170ef from qemu
exec-all.h contains TCG-specific definitions. It is not needed outside
TCG-specific files such as translate.c, exec.c or *helper.c.
One generic function had snuck into include/exec/exec-all.h; move it to
include/qom/cpu.h.
Backports commit 63c915526d6a54a95919ebece83fa9ca631b2508 from qemu
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
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
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
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
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
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
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
This will be shared by the next patch.
Also add a comment explaining the unobvious condition on "size.hi".
Backports commit 29cb533d8cbff1330717619780c2f1dfe764e003 from qemu
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
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
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
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
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
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Backports commit 7b31bbc2e68605ab2f10dc609dd54cf4c7b5f49a from qemu
address_space_translate_internal will clamp the *plen length argument
based on the size of the memory region being queried. The iommu walker
logic in addresss_space_translate was ignoring this by discarding the
post fn call value of *plen. Fix by just always using *plen as the
length argument throughout the fn, removing the len local variable.
This fixes a bootloader bug when a single elf section spans multiple
QEMU memory regions.
Backports commit 23820dbfc79d1c9dce090b4c555994f2bb6a69b3 from qemu
Add a MemoryRegion property, which if set is used to construct
the CPU's initial (default) AddressSpace.
Backports commit 6731d864f80938e404dc3e5eb7f6b76b891e3e43 from qemu
When accessing the dispatch pointer in an AddressSpace within an RCU
critical section we should always use atomic_rcu_read(). Fix an
access within memory_region_section_get_iotlb() which was incorrectly
doing a direct pointer access.
Backports commit 0b8e2c1002afddc8ef3d52fa6fc29e4768429f98 from qemu
check the return value of the function it calls and error if it's non-0
Fixup qemu_rdma_init_one_block that is the only current caller,
and rdma_add_block the only function it calls using it.
Pass the name of the ramblock to the function; helps in debugging.
Backports commit e3807054e20fb3b94d18cb751c437ee2f43b6fac from qemu
It is not necessary to munmap an area before remapping it with MAP_FIXED;
if the memory region specified by addr and len overlaps pages of any
existing mapping, then the overlapped part of the existing mapping will
be discarded.
On the other hand, if QEMU does munmap the pages, there is a small
probability that another mmap sneaks in and catches the just-freed
portion of the address space. In effect, munmap followed by
mmap(MAP_FIXED) is a use-after-free error, and Coverity flags it
as such. Fix it.
Backports commit f18c69cfc554cf9776eb3c35b7510e17541afacb from qemu
This reverts commit c3c1bb9.
It causes problems with boards that declare memory regions shorter
than the registers they contain.
Backports commit 4025446f0ac6213335c22ec43f3c3d8362ce7286 from qemu
Block size must fundamentally be a multiple of target page size.
Aligning automatically removes need to worry about the alignment
from callers.
Note: the only caller of qemu_ram_resize (acpi) already happens to have
size padded to a power of 2, but we would like to drop the padding in
ACPI core, and don't want to expose target page size knowledge to ACPI
Backports commit 129ddaf31be583fb7c97812e07e028661005ce42 from qemu
Allow "unlocked" reads of the ram_list by using an RCU-enabled QLIST.
The ramlist mutex is kept. call_rcu callbacks are run with the iothread
lock taken, but that may change in the future. Writers still take the
ramlist mutex, but they no longer need to assume that the iothread lock
is taken.
Readers of the list, instead, no longer require either the iothread
or ramlist mutex, but they need to use rcu_read_lock() and
rcu_read_unlock().
One place in arch_init.c was downgrading from write side to read side
like this:
qemu_mutex_lock_iothread()
qemu_mutex_lock_ramlist()
...
qemu_mutex_unlock_iothread()
...
qemu_mutex_unlock_ramlist()
and the equivalent idiom is:
qemu_mutex_lock_ramlist()
rcu_read_lock()
...
qemu_mutex_unlock_ramlist()
...
rcu_read_unlock()
Backports the write barriers from commit 0dc3f44aca18b1be8b425f3f4feb4b3e8d68de2e in qemu
Coverity flags this as "dereference after null check". Not quite a
dereference, since it will just EFAULT, but still nice to fix.
Backports commit a904c91196a9c5dbd7b9abcd3d40b0824286fb1c from qemu
The TARGET_HAS_ICE #define is intended to indicate whether a target-*
guest CPU implementation supports the breakpoint handling. However,
all our guest CPUs have that support (the only two which do not
define TARGET_HAS_ICE are unicore32 and openrisc, and in both those
cases the bp support is present and the lack of the #define is just
a bug). So remove the #define entirely: all new guest CPU support
should include breakpoint handling as part of the basic implementation.
Backports commit ec53b45bcd1f74f7a4c31331fa6d50b402cd6d26 from qemu
host pointer accesses force pointer math, let's
add a wrapper to make them safer.
Backports relevant parts of commit 1240be24357ee292f8d05aa2abfdba75dd0ca25d from qemu
Otherwise fw_cfg accesses are split into 4-byte ones before they reach the
fw_cfg ops / handlers.
Backports commit ff6cff7554be06e95f8d712f66cd16bd6681c746 from qemu
Loading the BIOS in the mac99 machine is interesting, because there is a
PROM in the middle of the BIOS region (from 16K to 32K). Before memory
region accesses were clamped, when QEMU was asked to load a BIOS from
0xfff00000 to 0xffffffff it would put even those 16K from the BIOS file
into the region. This is weird because those 16K were not actually
visible between 0xfff04000 and 0xfff07fff. However, it worked.
After clamping was added, this also worked. In this case, the
cpu_physical_memory_write_rom_internal function split the write in
three parts: the first 16K were copied, the PROM area (second 16K) were
ignored, then the rest was copied.
Problems then started with commit 965eb2f (exec: do not clamp accesses
to MMIO regions, 2015-06-17). Clamping accesses is not done for MMIO
regions because they can overlap wildly, and MMIO registers can be
expected to perform full-width accesses based only on their address
(with no respect for adjacent registers that could decode to completely
different MemoryRegions). However, this lack of clamping also applied
to the PROM area! cpu_physical_memory_write_rom_internal thus failed
to copy the third range above, i.e. only copied the first 16K of the BIOS.
In effect, address_space_translate is expecting _something else_ to do
the clamping for MMIO regions if the incoming length is large. This
"something else" is memory_access_size in the case of address_space_rw,
so use the same logic in cpu_physical_memory_write_rom_internal.
Backports commit b242e0e0e2969c044a318e56f7988bbd84de1f63 from qemu
Because the clamping was done against the MemoryRegion,
address_space_rw was effectively broken if a write spanned
multiple sections that are not linear in underlying memory
(with the memory not being under an IOMMU).
This is visible with the MIPS rc4030 IOMMU, which is implemented
as a series of alias memory regions that point to the actual RAM.
Backports commit e4a511f8cc6f4a46d409fb5c9f72c38ba45f8d83 from qemu
It is common for MMIO registers to overlap, for example a 4 byte register
at 0xcf8 (totally random choice... :)) and a 1 byte register at 0xcf9.
If these registers are implemented via separate MemoryRegions, it is
wrong to clamp the accesses as the value written would be truncated.
Hence for these regions the effects of commit 23820db (exec: Respect
as_translate_internal length clamp, 2015-03-16, previously applied as
commit c3c1bb9) must be skipped.
Backports commit 965eb2fcdfe919ecced6c34803535ad32dc1249c from qemu
Use cpu_get_phys_page_attrs_debug() when doing virtual-to-physical
conversions in debug related code, so that we can obtain the right
address space index and thus select the correct AddressSpace,
rather than always using cpu->as.
Backports commit 5232e4c798ba7a46261d3157b73d08fc598e7dcb from qemu
Add a function to return the AddressSpace for a CPU based on
its numerical index. (Callers outside exec.c don't have access
to the CPUAddressSpace struct so can't just fish it out of the
CPUState struct directly.)
Backports commit 651a5bc03705102de519ebf079a40ecc1da991db from qemu
Pass the MemTxAttrs for the memory access to iotlb_to_region(); this
allows it to determine the correct AddressSpace to use for the lookup.
Backports commit a54c87b68a0410d0cf6f8b84e42074a5cf463732 from qemu
When looking up the MemoryRegionSection for the new TLB entry in
tlb_set_page_with_attrs(), use cpu_asidx_from_attrs() to determine
the correct address space index for the lookup, and pass it into
address_space_translate_for_iotlb().
Backports commit d7898cda81b6efa6b2d7a749882695cdcf280eaa from qemu
Allow multiple calls to cpu_address_space_init(); each
call adds an entry to the cpu->ases array at the specified
index. It is up to the target-specific CPU code to actually use
these extra address spaces.
Since this multiple AddressSpace support won't work with
KVM, add an assertion to avoid confusing failures.
Backports commit 12ebc9a76dd7702aef0a3618717a826c19c34ef4 from qemu
Rather than setting cpu->as unconditionally in cpu_exec_init
(and then having target-i386 override this later), don't set
it until the first call to cpu_address_space_init.
This requires us to initialise the address space for
both TCG and KVM (KVM doesn't need the AS listener but
it does require cpu->as to be set).
For target CPUs which don't set up any address spaces (currently
everything except i386), add the default address_space_memory
in qemu_init_vcpu().
Backports commit 56943e8cc14b7eeeab67d1942fa5d8bcafe3e53f from qemu
memcpy can take a large amount of time for small reads and writes.
Handle the common case of reading s/g descriptors from memory (there
is no corresponding "write" case that is as common, because writes
often use address_space_st* functions) by inlining the relevant
parts of address_space_read into the caller.
Backports commit 3cc8f884996584630734a90c9b3c535af81e3c92 from qemu
We want to inline the case where there is only one iteration, because
then the compiler can also inline the memcpy. As a start, extract
everything after the first address_space_translate call.
Backports commit a203ac702e0720135fac8b1f2061d119814c1798 from qemu
Rather than dispatching on is_write for every iteration, make
address_space_rw call one of the two functions. The amount of
duplicate logic is pretty small, and memory_access_is_direct can
be tweaked so that it inlines better in the callers.
Backports commit eb7eeb88628074207dd611472e712af775985e73 from qemu
Replace qemu_ram_free_from_ptr() with qemu_ram_free().
The only difference between qemu_ram_free_from_ptr() and
qemu_ram_free() is that g_free_rcu() is used instead of
call_rcu(reclaim_ramblock). We can safely replace it because:
* RAM blocks allocated by qemu_ram_alloc_from_ptr() always have
RAM_PREALLOC set;
* reclaim_ramblock(block) will do nothing except g_free(block)
if RAM_PREALLOC is set at block->flags.
Backports commit a29ac16632aec6065c72985b9f7eeb1ca6fbef4a from qemu
memory_region_unref(mr) can free memory.
For example I got:
Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7f43280d4700 (LWP 4462)]
0x00007f43323283c0 in phys_section_destroy (mr=0x7f43259468b0)
at /home/don/xen/tools/qemu-xen-dir/exec.c:1023
1023 if (mr->subpage) {
(gdb) bt
at /home/don/xen/tools/qemu-xen-dir/exec.c:1023
at /home/don/xen/tools/qemu-xen-dir/exec.c:1034
at /home/don/xen/tools/qemu-xen-dir/exec.c:2205
(gdb) p mr
$1 = (MemoryRegion *) 0x7f43259468b0
And this change prevents this.
Backports commit 55b4e80b047300e1512df02887b7448ba3786b62 from qemu
Add a function to find a RAMBlock by name; use it in two
of the places that already open code that loop; we've
got another use later in postcopy.
Backports commit e3dd74934f2d2c8c67083995928ff68e8c1d0030 from qemu
Postcopy sends RAMBlock names and offsets over the wire (since it can't
rely on the order of ramaddr being the same), and it starts out with
HVA fault addresses from the kernel.
qemu_ram_block_from_host translates a HVA into a RAMBlock, an offset
in the RAMBlock and the global ram_addr_t value.
Rewrite qemu_ram_addr_from_host to use qemu_ram_block_from_host.
Provide qemu_ram_get_idstr since its the actual name text sent on the
wire.
Backports commit 422148d3e56c3c9a07c0cf36c1e0a0b76f09c357 from qemu
