Both qemu_vfio_find_fixed_iova() and qemu_vfio_find_temp_iova()
return an errno which is unused (or overwritten). Have them propagate
eventual errors to callers, returning a boolean (which is what the
Error API recommends, see commit e3fe3988d7 "error: Document Error
API usage rules" for rationale).
Suggested-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20210902070025.197072-9-philmd@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Extract qemu_vfio_water_mark_reached() for readability,
and have it provide an error hint it its Error* handle.
Suggested-by: Klaus Jensen <k.jensen@samsung.com>
Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20210902070025.197072-8-philmd@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Currently qemu_vfio_dma_map() displays errors on stderr.
When using management interface, this information is simply
lost. Pass qemu_vfio_dma_map() an Error** handle so it can
propagate the error to callers.
Reviewed-by: Fam Zheng <fam@euphon.net>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20210902070025.197072-7-philmd@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
qemu_vfio_add_mapping() returns a pointer to an indexed entry
in pre-allocated QEMUVFIOState::mappings[], thus can not be NULL.
Remove the pointless check.
Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20210902070025.197072-5-philmd@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Simplify qemu_vfio_dma_[un]map() handlers by replacing a pair of
qemu_mutex_lock/qemu_mutex_unlock calls by the WITH_QEMU_LOCK_GUARD
macro.
Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20210902070025.197072-4-philmd@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Instead of displaying the error on stderr, use error_report()
which also report to the monitor.
Reviewed-by: Fam Zheng <fam@euphon.net>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20210902070025.197072-3-philmd@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Commit 776b97d360 "qemu-sockets: add abstract UNIX domain socket
support" neglected to update socket_sockaddr_to_address_unix() and
copied the whole sun_path without taking "salen" into account.
Later, commit 3b14b4ec49 "sockets: Fix socket_sockaddr_to_address_unix()
for abstract sockets" handled the abstract UNIX path, by stripping the
leading \0 character and fixing address details, but didn't use salen
either.
Not taking "salen" into account may result in incorrect "path" being
returned in monitors commands, as we read past the address which is not
necessarily \0-terminated.
Fixes: 776b97d360
Fixes: 3b14b4ec49
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: xiaoqiang zhao <zxq_yx_007@163.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
From clang-13:
util/selfmap.c:26:21: error: variable 'errors' set but not used \
[-Werror,-Wunused-but-set-variable]
Quite right of course, but there's no reason not to check errors.
First, incrementing errors is incorrect, because qemu_strtoul
returns an errno not a count -- just or them together so that
we have a non-zero value at the end.
Second, if we have an error, do not add the struct to the list,
but free it instead.
Cc: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Commit d8fb7d0969 ("vl: switch -M parsing
to keyval") stopped adding the "machine" QemuOptsList. This causes
"machine" options to not show up in QMP query-command-line-options
output. For example, libvirt cannot detect that kernel_irqchip support
is available.
Adjust the "machine" opts enumeration in
qmp_query_command_line_options() so that options are properly reported.
Fixes: d8fb7d0969 ("vl: switch -M parsing to keyval")
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20210721151055.424580-1-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use it to avoid some clang-12 -Watomic-alignment errors,
forcing some structures to be aligned and as a pointer when
we have ensured that the address is aligned.
Tested-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The `aio-max-batch` parameter will be propagated to AIO engines
and it will be used to control the maximum number of queued requests.
When there are in queue a number of requests equal to `aio-max-batch`,
the engine invokes the system call to forward the requests to the kernel.
This parameter allows us to control the maximum batch size to reduce
the latency that requests might accumulate while queued in the AIO
engine queue.
If `aio-max-batch` is equal to 0 (default value), the AIO engine will
use its default maximum batch size value.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20210721094211.69853-3-sgarzare@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The leak is basically impossible to reach, since the only common way
to get ferror(fp) is by passing a directory to -readconfig. In that
case, the error occurs before qdict is set to anything non-NULL.
However, it's theoretically possible to get there after an EIO.
Cc: armbru@redhat.com
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Fixes: f7544edcd3 ("qemu-config: add error propagation to qemu_config_parse", 2021-03-06)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Ensure that the callback to qemu_config_foreach is never called upon
an error, by moving the invocation before the "out" label.
Cc: armbru@redhat.com
Fixes: 3770141139 ("qemu-config: parse configuration files to a QDict", 2021-06-04)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- Make blockdev-reopen stable
- Remove deprecated qemu-img backing file without format
- rbd: Convert to coroutines and add write zeroes support
- rbd: Updated MAINTAINERS
- export/fuse: Allow other users access to the export
- vhost-user: Fix backends without multiqueue support
- Fix drive-backup transaction endless drained section
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block layer patches
- Make blockdev-reopen stable
- Remove deprecated qemu-img backing file without format
- rbd: Convert to coroutines and add write zeroes support
- rbd: Updated MAINTAINERS
- export/fuse: Allow other users access to the export
- vhost-user: Fix backends without multiqueue support
- Fix drive-backup transaction endless drained section
# gpg: Signature made Fri 09 Jul 2021 13:49:22 BST
# gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg: issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6
* remotes/kevin/tags/for-upstream: (28 commits)
block: Make blockdev-reopen stable API
iotests: Test reopening multiple devices at the same time
block: Support multiple reopening with x-blockdev-reopen
block: Acquire AioContexts during bdrv_reopen_multiple()
block: Add bdrv_reopen_queue_free()
qcow2: Fix dangling pointer after reopen for 'file'
qemu-img: Improve error for rebase without backing format
qemu-img: Require -F with -b backing image
qcow2: Prohibit backing file changes in 'qemu-img amend'
blockdev: fix drive-backup transaction endless drained section
vhost-user: Fix backends without multiqueue support
MAINTAINERS: add block/rbd.c reviewer
block/rbd: fix type of task->complete
iotests/fuse-allow-other: Test allow-other
iotests/308: Test +w on read-only FUSE exports
export/fuse: Let permissions be adjustable
export/fuse: Give SET_ATTR_SIZE its own branch
export/fuse: Add allow-other option
export/fuse: Pass default_permissions for mount
util/uri: do not check argument of uri_free()
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
We know that in the body of this if statement i is less than len, so
we really should be copying len - i bytes not i - len bytes.
Fix this typo.
Fixes: 8d8404f156 ("util: Add qemu_guest_getrandom and associated routines")
Signed-off-by: Mark Nelson <mdnelson8@gmail.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210709120600.11080-1-mdnelson8@gmail.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
With target-specific modules we can have multiple modules implementing
the same object. Therefore we have to check the target arch on lookup
to find the correct module.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-20-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add module_allow_arch() to set the target architecture.
In case a module is limited to some arch verify arches
match and ignore the module if not.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-19-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
One for module load and one for qom type lookup.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-18-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use module database to figure which module adds given QemuOpts group.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-17-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use module database to figure which module implements a given QOM type.
Drop hard-coded object list.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-16-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use module database for module dependencies.
Drop hard-coded dependency list.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-15-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add script to generate C source with a small
database containing the module meta-data.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jose R. Ziviani <jziviani@suse.de>
Message-Id: <20210624103836.2382472-4-kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
While most libraries do not need a CONFIG_* symbol because the
"when:" clauses are enough, some do. Add them back or stop
using them if possible.
In the case of libpmem, the statement to add the CONFIG_* symbol
was still in configure, but could not be triggered because it
checked for "no" instead of "disabled" (and it would be wrong anyway
since the test for the library has not been done yet).
Reported-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Fixes: 587d59d6cc ("configure, meson: convert virgl detection to meson", 2021-07-06)
Fixes: 83ef16821a ("configure, meson: convert libdaxctl detection to meson", 2021-07-06)
Fixes: e36e8c70f6 ("configure, meson: convert libpmem detection to meson", 2021-07-06)
Fixes: 53c22b68e3 ("configure, meson: convert liburing detection to meson", 2021-07-06)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
uri_free() checks if its argument is NULL in uri_clean() and g_free().
There is no need to check the argument before the call.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Message-Id: <20210629063602.4239-1-xypron.glpk@gmx.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
It is not safe to pretend that emulated NVDIMM supports
persistence while backend actually failed to enable it
and used non-persistent mapping as fall back.
Instead of falling-back, QEMU should be more strict and
error out with clear message that it's not supported.
So if user asks for persistence (pmem=on), they should
store backing file on NVDIMM.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210111203332.740815-1-imammedo@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
-M was the sole user of qemu_opts_set and qemu_opts_set_defaults,
remove them and the arguments that they used.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Allow parsing multiple keyval sequences into the same dictionary.
This will be used to simplify the parsing of the -M command line
option, which is currently a .merge_lists = true QemuOpts group.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch introduces a function that merges two keyval-produced
(or keyval-like) QDicts. It can be used to emulate the behavior of
.merge_lists = true QemuOpts groups, merging -readconfig sections and
command-line options in a single QDict, and also to implement -set.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
BHs must be deleted before the AioContext is finalized. If not, it's a
bug and probably indicates that some part of the program still expects
the BH to run in the future. That can lead to memory leaks, inconsistent
state, or just hangs.
Unfortunately the assert(flags & BH_DELETED) call in aio_ctx_finalize()
is difficult to debug because the assertion failure contains no
information about the BH!
Use the QEMUBH name field added in the previous patch to show a useful
error when a leaked BH is detected.
Suggested-by: Eric Ernst <eric.g.ernst@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20210414200247.917496-3-stefanha@redhat.com>
It can be difficult to debug issues with BHs in production environments.
Although BHs can usually be identified by looking up their ->cb()
function pointer, this requires debug information for the program. It is
also not possible to print human-readable diagnostics about BHs because
they have no identifier.
This patch adds a name to each BH. The name is not unique per instance
but differentiates between cb() functions, which is usually enough. It's
done by changing aio_bh_new() and friends to macros that stringify cb.
The next patch will use the name field when reporting leaked BHs.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210414200247.917496-2-stefanha@redhat.com>
co-shared-resource is currently not thread-safe, as also reported
in co-shared-resource.h. Add a QemuMutex because co_try_get_from_shres
can also be invoked from non-coroutine context.
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20210614081130.22134-6-eesposit@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
The function is called with alignment == 0 which caused an assertion.
Use the code from oslib-posix.c to fix that regression.
Fixes: ed6f53f9ca
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210611105846.347954-1-sw@weilnetz.de>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Add function that transforms named fd inside SocketAddress structure
into number representation. This way it may be then used in a context
where current monitor is not available.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20210610100802.5888-6-vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[eblake: comment tweak]
Signed-off-by: Eric Blake <eblake@redhat.com>
If we want to wake up a coroutine from a worker thread, aio_co_wake()
currently does not work. In that scenario, aio_co_wake() calls
aio_co_enter(), but there is no current AioContext and therefore
qemu_get_current_aio_context() returns the main thread. aio_co_wake()
then attempts to call aio_context_acquire() instead of going through
aio_co_schedule().
The default case of qemu_get_current_aio_context() was added to cover
synchronous I/O started from the vCPU thread, but the main and vCPU
threads are quite different. The main thread is an I/O thread itself,
only running a more complicated event loop; the vCPU thread instead
is essentially a worker thread that occasionally calls
qemu_mutex_lock_iothread(). It is only in those critical sections
that it acts as if it were the home thread of the main AioContext.
Therefore, this patch detaches qemu_get_current_aio_context() from
iothreads, which is a useless complication. The AioContext pointer
is stored directly in the thread-local variable, including for the
main loop. Worker threads (including vCPU threads) optionally behave
as temporary home threads if they have taken the big QEMU lock,
but if that is not the case they will always schedule coroutines
on remote threads via aio_co_schedule().
With this change, the stub qemu_mutex_iothread_locked() must be changed
from true to false. The previous value of true was needed because the
main thread did not have an AioContext in the thread-local variable,
but now it does have one.
Reported-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20210609122234.544153-1-pbonzini@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Tested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[eblake: tweak commit message per Vladimir's review]
Signed-off-by: Eric Blake <eblake@redhat.com>
We will shortly convert lockable.h to _Generic, and we cannot
have two compatible types in the same expansion. Wrap QemuMutex
in a struct, and unwrap in qemu-thread-posix.c.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210614233143.1221879-6-richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Create macros for file+line expansion in qemu_rec_mutex_unlock
like we have for qemu_mutex_unlock.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210614233143.1221879-5-richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the declarations from thread-win32.h into thread.h
and remove the macro redirection from thread-posix.h.
This will be required by following cleanups.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210614233143.1221879-4-richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Let's support RAM_NORESERVE via MAP_NORESERVE on Linux. The flag has no
effect on most shared mappings - except for hugetlbfs and anonymous memory.
Linux man page:
"MAP_NORESERVE: Do not reserve swap space for this mapping. When swap
space is reserved, one has the guarantee that it is possible to modify
the mapping. When swap space is not reserved one might get SIGSEGV
upon a write if no physical memory is available. See also the discussion
of the file /proc/sys/vm/overcommit_memory in proc(5). In kernels before
2.6, this flag had effect only for private writable mappings."
Note that the "guarantee" part is wrong with memory overcommit in Linux.
Also, in Linux hugetlbfs is treated differently - we configure reservation
of huge pages from the pool, not reservation of swap space (huge pages
cannot be swapped).
The rough behavior is [1]:
a) !Hugetlbfs:
1) Without MAP_NORESERVE *or* with memory overcommit under Linux
disabled ("/proc/sys/vm/overcommit_memory == 2"), the following
accounting/reservation happens:
For a file backed map
SHARED or READ-only - 0 cost (the file is the map not swap)
PRIVATE WRITABLE - size of mapping per instance
For an anonymous or /dev/zero map
SHARED - size of mapping
PRIVATE READ-only - 0 cost (but of little use)
PRIVATE WRITABLE - size of mapping per instance
2) With MAP_NORESERVE, no accounting/reservation happens.
b) Hugetlbfs:
1) Without MAP_NORESERVE, huge pages are reserved.
2) With MAP_NORESERVE, no huge pages are reserved.
Note: With "/proc/sys/vm/overcommit_memory == 0", we were already able
to configure it for !hugetlbfs globally; this toggle now allows
configuring it more fine-grained, not for the whole system.
The target use case is virtio-mem, which dynamically exposes memory
inside a large, sparse memory area to the VM.
[1] https://www.kernel.org/doc/Documentation/vm/overcommit-accounting
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com> for memory backend and machine core
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210510114328.21835-10-david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Let's introduce RAM_NORESERVE, allowing mmap'ing with MAP_NORESERVE. The
new flag has the following semantics:
"
RAM is mmap-ed with MAP_NORESERVE. When set, reserving swap space (or huge
pages if applicable) is skipped: will bail out if not supported. When not
set, the OS will do the reservation, if supported for the memory type.
"
Allow passing it into:
- memory_region_init_ram_nomigrate()
- memory_region_init_resizeable_ram()
- memory_region_init_ram_from_file()
... and teach qemu_ram_mmap() and qemu_anon_ram_alloc() about the flag.
Bail out if the flag is not supported, which is the case right now for
both, POSIX and win32. We will add Linux support next and allow specifying
RAM_NORESERVE via memory backends.
The target use case is virtio-mem, which dynamically exposes memory
inside a large, sparse memory area to the VM.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com> for memory backend and machine core
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210510114328.21835-9-david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Let's pass flags instead of bools to prepare for passing other flags and
update the documentation of qemu_ram_mmap(). Introduce new QEMU_MAP_
flags that abstract the mmap() PROT_ and MAP_ flag handling and simplify
it.
We expose only flags that are currently supported by qemu_ram_mmap().
Maybe, we'll see qemu_mmap() in the future as well that can implement these
flags.
Note: We don't use MAP_ flags as some flags (e.g., MAP_SYNC) are only
defined for some systems and we want to always be able to identify
these flags reliably inside qemu_ram_mmap() -- for example, to properly
warn when some future flags are not available or effective on a system.
Also, this way we can simplify PROT_ handling as well.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Eduardo Habkost <ehabkost@redhat.com> for memory backend and machine core
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210510114328.21835-8-david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
