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
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
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
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
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
This will either create a new AS or return a pointer to an
already existing equivalent one, if we have already created
an AS for the specified root memory region.
The motivation is to reuse address spaces as much as possible.
It's going to be quite common that bus masters out in device land
have pointers to the same memory region for their mastering yet
each will need to create its own address space. Let the memory
API implement sharing for them.
Aside from the perf optimisations, this should reduce the amount
of redundant output on info mtree as well.
Thee returned value will be malloced, but the malloc will be
automatically freed when the AS runs out of refs.
Backports commit f0c02d15b57da6f5463e3768aa0cfeedccf4b8f4 from qemu
For the common case of DMA into non-hotplugged RAM, it is unnecessary
but expensive to do object_ref/unref. Add back an owner field to
MemoryRegion, so that these memory regions can skip the reference
counting.
Backports commit 612263cf33062f7441a5d0e3b37c65991fdc3210 from qemu
The function is equivalent to memory_region_destructor_ram(), so
it's not needed anymore.
Backports commit fc3e7665d7fe1b2f842441d250d7afec26b8a910 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
This makes ROM blocks resizeable. This infrastructure is required for other
functionality we have queued.
Backports commit aaf03019175949eda5087329448b8a0033b89479 from qemu
osdep.h has a few things which are really compiler specific;
move them to compiler.h, and include compiler.h from osdep.h.
Backports commit 4912086865083a008f4fb73173fd0ddf2206c4d9 from qemu
This is legal; the MemoryRegion will simply unreference all the
existing subregions and possibly bring them down with it as well.
However, it requires a bit of care to avoid an infinite loop.
Finalizing a memory region cannot trigger an address space update,
but memory_region_del_subregion errs on the side of caution and
might trigger a spurious update: avoid that by resetting mr->enabled
first.
Backports commit 91232d98da2bfe042d4c5744076b488880de3040 from qemu
This introduces the memory region property "global_locking". It is true
by default. By setting it to false, a device model can request BQL-free
dispatching of region accesses to its r/w handlers. The actual BQL
break-up will be provided in a separate patch.
Backports commit 196ea13104f802c508e57180b2a0d2b3418989a3 from qemu
mr->terminates alone doesn't guarantee that we are looking at a RAM region.
mr->ram_addr also has to be checked, in order to distinguish RAM and I/O
regions.
So, do the following:
1) add a new define RAM_ADDR_INVALID, and test it in the assertions
instead of mr->terminates
2) IOMMU regions were not setting mr->ram_addr to a bogus value, initialize
it in the instance_init function so that the new assertions would fire
for IOMMU regions as well.
Backports commit ec05ec26f940564b1e07bf88857035ec27e21dd8 from qemu
The cpu_physical_memory_reset_dirty() function is sometimes used
together with cpu_physical_memory_get_dirty(). This is not atomic since
two separate accesses to the dirty memory bitmap are made.
Turn cpu_physical_memory_reset_dirty() and
cpu_physical_memory_clear_dirty_range_type() into the atomic
cpu_physical_memory_test_and_clear_dirty().
Backports commit 03eebc9e3246b9b3f5925aa41f7dfd7c1e467875 from qemu
DIRTY_MEMORY_CODE is only needed for TCG. By adding it directly to
mr->dirty_log_mask, we avoid testing for TCG everywhere a region is
checked for the enabled/disabled state of dirty logging.
Backports commit 677e7805cf95f3b2bca8baf0888d1ebed7f0c606 from qemu
When the dirty log mask will also cover other bits than DIRTY_MEMORY_VGA,
some listeners may be interested in the overall zero/non-zero value of
the dirty log mask; others may be interested in the value of single bits.
For this reason, always call log_start/log_stop if bits have respectively
appeared or disappeared, and pass the old and new values of the dirty log
mask so that listeners can distinguish the kinds of change.
For example, KVM checks if dirty logging used to be completely disabled
(in log_start) or is now completely disabled (in log_stop). On the
other hand, Xen has to check manually if DIRTY_MEMORY_VGA changed,
since that is the only bit it cares about.
Backports commit b2dfd71c4843a762f2befe702adb249cf55baf66 from qemu
For now memory regions only track DIRTY_MEMORY_VGA individually, but
this will change soon. To support this, split memory_region_is_logging
in two functions: one that returns a given bit from dirty_log_mask,
and one that returns the entire mask. memory_region_is_logging gets an
extra parameter so that the compiler flags misuse.
While VGA-specific users (including the Xen listener!) will want to keep
checking that bit, KVM and vhost check for "any bit except migration"
(because migration is handled via the global start/stop listener
callbacks).
Backports commit 2d1a35bef0ed96b3f23535e459c552414ccdbafd from qemu
Rather than retaining io_mem_read/write as simple wrappers around
the memory_region_dispatch_read/write functions, make the latter
public and change all the callers to use them, since we need to
touch all the callsites anyway to add MemTxAttrs and MemTxResult
support. Delete io_mem_read and io_mem_write entirely.
(All the callers currently pass MEMTXATTRS_UNSPECIFIED
and convert the return value back to bool or ignore it.)
Backports commit 3b6434953934e6d4a776ed426d8c6d6badee176f from qemu
Define an API so that devices can register MemoryRegionOps whose read
and write callback functions are passed an arbitrary pointer to some
transaction attributes and can return a success-or-failure status code.
This will allow us to model devices which:
* behave differently for ARM Secure/NonSecure memory accesses
* behave differently for privileged/unprivileged accesses
* may return a transaction failure (causing a guest exception)
for erroneous accesses
This patch defines the new API and plumbs the attributes parameter through
to the memory.c public level functions io_mem_read() and io_mem_write(),
where it is currently dummied out.
The success/failure response indication is also propagated out to
io_mem_read() and io_mem_write(), which retain the old-style
boolean true-for-error return.
Backports commit cc05c43ad942165ecc6ffd39e41991bee43af044 from qemu
This commit fixes the following issues:
- Any unmapped/free'd memory regions (MemoryRegion instances) are not
removed from the object property linked list of its owner (which is
always qdev_get_machine(uc)). This issue makes adding new memory
mapping by calling mem_map() or mem_map_ptr() slower as more and more
memory pages are mapped and unmapped - yes, even if those memory pages
are unmapped, they still impact the speed of future memory page
mappings due to this issue.
- FlatView is not reconstructed after a memory region is freed during
unmapping, which leads to a use-after-free the next time a new memory
region is mapped in address_space_update_topology().
ARM and probably the rest of the arches have significant memory leaks as
they have no release interface.
Additionally, DrMemory does not have 64-bit support and thus I can't
test the 64-bit version under Windows. Under Linux valgrind supports
both 32-bit and 64-bit but there are different macros and code for Linux
and Windows.
It appears the problem is that we are not calling the memory region
destructor. After modifying memory_unmap to include the destructor call
for the memory region, the memory is freed.
Furthermore in uc_close we must explicitly free any blocks that were not
unmapped by the user to prevent leaks.
This should fix issue 305.
