We added @error_warn some two years ago in commit 3ffef1a55c (error:
add global &error_warn destination). It has multiple issues:
* error.h's big comment was not updated for it.
* Function contracts were not updated for it.
* ERRP_GUARD() is unaware of @error_warn, and fails to mask it from
error_prepend() and such. These crash on @error_warn, as pointed
out by Akihiko Odaki.
All fixable. However, after more than two years, we had just of 15
uses, of which the last few patches removed seven as unclean or
otherwise undesirable, adding back five elsewhere. I didn't look
closely enough at the remaining seven to decide whether they are
desirable or not.
I don't think this feature earns its keep. Drop it.
Thanks-to: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-ID: <20250923091000.3180122-14-armbru@redhat.com>
Reviewed-by: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
qemu_socket_select() and its wrapper qemu_socket_unselect() treat a
null @errp as &error_warn. This is wildly inappropriate. A caller
passing null @errp specifies that errors are to be ignored. If
warnings are wanted, the caller must pass &error_warn.
Change callers to do that, and drop the inappropriate treatment of
null @errp.
This assumes that warnings are wanted. I'm not familiar with the
calling code, so I can't say whether it will work when the socket is
invalid, or WSAEventSelect() fails. If it doesn't, then this should
be an error instead of a warning. Invalid socket might even be a
programming error.
These warnings were introduced in commit f5fd677ae7 (win32/socket:
introduce qemu_socket_select() helper). I considered reverting to
silence, but Daniel Berrangé asked for the warnings to be preserved.
Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20250923091000.3180122-9-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Akihiko Odaki <odaki@rsg.ci.i.u-tokyo.ac.jp>
Use common qemu_set_blocking() instead.
Note that pre-patch the behavior of Win32 and Linux realizations
are inconsistent: we ignore failure for Win32, and assert success
for Linux.
How do we convert the callers?
1. Most of callers call qemu_socket_set_nonblock() on a
freshly created socket fd, in conditions when we may simply
report an error. Seems correct switching to error handling
both for Windows (pre-patch error is ignored) and Linux
(pre-patch we assert success). Anyway, we normally don't
expect errors in these cases.
Still in tests let's use &error_abort for simplicity.
What are exclusions?
2. hw/virtio/vhost-user.c - we are inside #ifdef CONFIG_LINUX,
so no damage in switching to error handling from assertion.
3. io/channel-socket.c: here we convert both old calls to
qemu_socket_set_nonblock() and qemu_socket_set_block() to
one new call. Pre-patch we assert success for Linux in
qemu_socket_set_nonblock(), and ignore all other errors here.
So, for Windows switch is a bit dangerous: we may get
new errors or crashes(when error_abort is passed) in
cases where we have silently ignored the error before
(was it correct in all such cases, if they were?) Still,
there is no other way to stricter API than take
this risk.
4. util/vhost-user-server - compiled only for Linux (see
util/meson.build), so we are safe, switching from assertion to
&error_abort.
Note: In qga/channel-posix.c we use g_warning(), where g_printerr()
would actually be a better choice. Still let's for now follow
common style of qga, where g_warning() is commonly used to print
such messages, and no call to g_printerr(). Converting everything
to use g_printerr() should better be another series.
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In generic code we have qio_channel_set_blocking(), which takes
bool parameter, and qemu_file_set_blocking(), which as well takes
bool parameter.
At lower fd-layer we have a mess of functions:
- enough direct calls to Unix-specific g_unix_set_fd_nonblocking()
(of course, all calls are out of Windows-compatible code), which
is glib specific with GError, which we can't use, and have to
handle error-reporting by hand after the call.
and several platform-agnostic qemu_* helpers:
- qemu_socket_set_nonblock(), which asserts success for posix (still,
in most cases we can handle the error in better way) and ignores
error for win32 realization
- qemu_socket_try_set_nonblock(), providing and error, but not errp,
so we have to handle it after the call
- qemu_socket_set_block(), which simply ignores an error
Note, that *_socket_* word in original API, which we are going
to substitute was intended, because Windows support these operations
only for sockets. What leads to solution of dropping it again?
1. Having a QEMU-native wrapper with errp parameter
for g_unix_set_fd_nonblocking() for non-socket fds worth doing,
at least to unify error handling.
2. So, if try to keep _socket_ vs _file_ words, we'll have two
actually duplicated functions for Linux, which actually will
be executed successfully on any (good enough) fds, and nothing
prevent using them improperly except for the name. That doesn't
look good.
3. Naming helped us in the world where we crash on errors or
ignore them. Now, with errp parameter, callers are intended to
proper error checking. And for places where we really OK with
crash-on-error semantics (like tests), we have an explicit
&error_abort.
So, this commit starts a series, which will effectively revert
commit ff5927baa7 "util: rename qemu_*block() socket functions"
(which in turn was reverting f9e8cacc55
"oslib-posix: rename socket_set_nonblock() to qemu_set_nonblock()",
so that's a long story).
Now we don't simply rename, instead we provide the new API and
update all the callers.
This commit only introduces a new fd-layer wrapper. Next commits
will replace old API calls with it, and finally remove old API.
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
QEMU initializes preallocated backend memory as the objects are parsed from
the command line. This is not optimal in some cases (e.g. memory spanning
multiple NUMA nodes) because the memory objects are initialized in series.
Allow the initialization to occur in parallel (asynchronously). In order to
ensure optimal thread placement, asynchronous initialization requires prealloc
context threads to be in use.
Signed-off-by: Mark Kanda <mark.kanda@oracle.com>
Message-ID: <20240131165327.3154970-2-mark.kanda@oracle.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Clang complains:
../util/oslib-win32.c:483:56: error: omitting the parameter name in a
function definition is a C2x extension [-Werror,-Wc2x-extensions]
win32_close_exception_handler(struct _EXCEPTION_RECORD*,
^
Fix it by adding parameter names.
Message-Id: <20230728142748.305341-4-thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Introduce qemu_win32_map_alloc() and qemu_win32_map_free() to allocate
shared memory mapping. The handle can be used to share the mapping with
another process.
Teach qemu_create_displaysurface() to allocate shared memory. Following
patches will introduce other places for shared memory allocation.
Other patches for -display dbus will share the memory when possible with
the client, to avoid expensive memory copy between the processes.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20230606115658.677673-10-marcandre.lureau@redhat.com>
Since commit abe34282 ("win32: avoid mixing SOCKET and file descriptor
space"), we set HANDLE_FLAG_PROTECT_FROM_CLOSE on the socket FD, to
prevent closing the HANDLE with CloseHandle. This raises an exception
which under gdb is fatal, and qemu exits.
Let's catch the expected error instead.
Note: this appears to work, but the mingw64 macro is not well documented
or tested, and it's not obvious how it is meant to be used.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20230515132440.1025315-1-marcandre.lureau@redhat.com>
Manually implement a socketpair() function, using UNIX sockets and
simple peer credential checking.
QEMU doesn't make much use of socketpair, beside vhost-user which is not
available for win32 at this point. However, I intend to use it for
writing some new portable tests.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20230306122751.2355515-5-marcandre.lureau@redhat.com>
Until now, a win32 SOCKET handle is often cast to an int file
descriptor, as this is what other OS use for sockets. When necessary,
QEMU eventually queries whether it's a socket with the help of
fd_is_socket(). However, there is no guarantee of conflict between the
fd and SOCKET space. Such conflict would have surprising consequences,
we shouldn't mix them.
Also, it is often forgotten that SOCKET must be closed with
closesocket(), and not close().
Instead, let's make the win32 socket wrapper functions return and take a
file descriptor, and let util/ wrappers do the fd/SOCKET conversion as
necessary. A bit of adaptation is necessary in io/ as well.
Unfortunately, we can't drop closesocket() usage, despite
_open_osfhandle() documentation claiming transfer of ownership, testing
shows bad behaviour if you forget to call closesocket().
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Message-Id: <20230221124802.4103554-15-marcandre.lureau@redhat.com>
The comment about g_poll is not required here anymore since
the corresponding code has been removed a while ago already.
Fixes: b4c6036faa ("configure: bump min required glib version to 2.56")
Message-Id: <20221208133257.95673-1-thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
... and implement it under POSIX. When a ThreadContext is provided,
create new threads via the context such that these new threads obtain a
properly configured CPU affinity.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Message-Id: <20221014134720.168738-6-david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's
* give the function a "qemu_*" style name
* make sure the parameters in the implementation match the prototype
* rename smp_cpus to max_threads, which makes the semantics of that
parameter clearer
... and add a function documentation.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Message-Id: <20221014134720.168738-2-david@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
The qemu_*block() functions are meant to be be used with sockets (the
win32 implementation expects SOCKET)
Over time, those functions where used with Win32 SOCKET or
file-descriptors interchangeably. But for portability, they must only be
used with socket-like file-descriptors. FDs can use
g_unix_set_fd_nonblocking() instead.
Rename the functions with "socket" in the name to prevent bad usages.
This is effectively reverting commit f9e8cacc55 ("oslib-posix:
rename socket_set_nonblock() to qemu_set_nonblock()").
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Replace the global variables with inlined helper functions. getpagesize() is very
likely annotated with a "const" function attribute (at least with glibc), and thus
optimization should apply even better.
This avoids the need for a constructor initialization too.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20220323155743.1585078-12-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The qemu_try_memalign() functions for POSIX and Windows used to be
significantly different, but these days they are identical except for
the actual allocation function called, and the POSIX version already
has to have ifdeffery for different allocation functions.
Move to a single implementation in memalign.c, which uses the Windows
_aligned_malloc if we detect that function in meson.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220226180723.1706285-7-peter.maydell@linaro.org
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Currently qemu_try_memalign()'s behaviour if asked to allocate
0 bytes is rather variable:
* on Windows, we will assert
* on POSIX platforms, we get the underlying behaviour of
the posix_memalign() or equivalent function, which may be
either "return a valid non-NULL pointer" or "return NULL"
Explictly check for 0 byte allocations, so we get consistent
behaviour across platforms. We handle them by incrementing the size
so that we return a valid non-NULL pointer that can later be passed
to qemu_vfree(). This is permitted behaviour for the
posix_memalign() API and is the most usual way that underlying
malloc() etc implementations handle a zero-sized allocation request,
because it won't trip up calling code that assumes NULL means an
error. (This includes our own qemu_memalign(), which will abort on
NULL.)
This change is a preparation for sharing the qemu_try_memalign() code
between Windows and POSIX.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
We implement qemu_memalign() in both oslib-posix.c and oslib-win32.c,
but the two versions are essentially the same: they call
qemu_try_memalign(), and abort() after printing an error message if
it fails. The only difference is that the win32 version prints the
GetLastError() value whereas the POSIX version prints
strerror(errno). However, this is a bug in the win32 version: in
commit dfbd0b873a in 2020 we changed the implementation of
qemu_try_memalign() from using VirtualAlloc() (which sets the
GetLastError() value) to using _aligned_malloc() (which sets errno),
but didn't update the error message to match.
Replace the two separate functions with a single version in a
new memalign.c file, which drops the unnecessary extra qemu_oom_check()
function and instead prints a more useful message including the
requested size and alignment as well as the errno string.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220226180723.1706285-4-peter.maydell@linaro.org
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
* Introduces qemu_fopen, qemu_access wrappers, and modifies qemu_open to
support converting stored UTF-8 paths to UTF-16 to use Unicode
filesystem API on Windows platform.
* Migrates several native open, fopen, and access calls to their
qemu_* counterparts to resolve Unicode path handling issues on
Windows.
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>
The glib version was not previously constrained by RHEL-7 since it
rebases fairly often. Instead SLES 12 and Ubuntu 16.04 were the
constraints in 00f2cfbbec. Both of
these are old enough that they are outside our platform support
matrix now.
Per repology, current shipping versions are:
RHEL-8: 2.56.4
Debian Buster: 2.58.3
openSUSE Leap 15.2: 2.62.6
Ubuntu LTS 18.04: 2.56.4
Ubuntu LTS 20.04: 2.64.6
FreeBSD: 2.66.7
Fedora 33: 2.66.8
Fedora 34: 2.68.1
OpenBSD: 2.68.1
macOS HomeBrew: 2.68.1
Thus Ubuntu LTS 18.04 / RHEL-8 are the constraint for GLib version
at 2.56
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20210514120415.1368922-11-berrange@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
On Windows with glib <2.50, g_poll is redefined to use the variant
defined in util/oslib-win32.c. Use the same name in the declaration
and definition for ease of grepping.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Matt Borgerson