Add flags to io_writev and introduce io_flush as optional callback to
QIOChannelClass, allowing the implementation of zero copy writes by
subclasses.
How to use them:
- Write data using qio_channel_writev*(...,QIO_CHANNEL_WRITE_FLAG_ZERO_COPY),
- Wait write completion with qio_channel_flush().
Notes:
As some zero copy write implementations work asynchronously, it's
recommended to keep the write buffer untouched until the return of
qio_channel_flush(), to avoid the risk of sending an updated buffer
instead of the buffer state during write.
As io_flush callback is optional, if a subclass does not implement it, then:
- io_flush will return 0 without changing anything.
Also, some functions like qio_channel_writev_full_all() were adapted to
receive a flag parameter. That allows shared code between zero copy and
non-zero copy writev, and also an easier implementation on new flags.
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20220513062836.965425-3-leobras@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Currently "qemu/error-report.h" is implicitly included, however
if headers in include/ get refactored, we get:
hw/remote/proxy-memory-listener.c: In function ‘proxy_memory_listener_commit’:
hw/remote/proxy-memory-listener.c:183:9: error: implicit declaration of function ‘error_report’; did you mean ‘error_report_err’? [-Werror=implicit-function-declaration]
183 | error_report("Number of fds is more than %d", REMOTE_MAX_FDS);
| ^~~~~~~~~~~~
| error_report_err
Add the missing "qemu/error-report.h" header to avoid that.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220207082756.82600-3-f4bug@amsat.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Macro ERRP_GUARD() is only needed when we want to dereference @errp or
pass it to error_prepend() or error_append_hint(). Delete superfluous
ones.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210720125408.387910-15-armbru@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
The Error ** argument must be NULL, &error_abort, &error_fatal, or a
pointer to a variable containing NULL. Passing an argument of the
latter kind twice without clearing it in between is wrong: if the
first call sets an error, it no longer points to NULL for the second
call.
pci_proxy_dev_realize() is wrong that way: it passes @errp to
qio_channel_new_fd() without checking for failure. If it runs into
another failure, it trips error_setv()'s assertion.
Fix it to check for failure properly.
Fixes: 9f8112073a
Cc: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Cc: Jagannathan Raman <jag.raman@oracle.com>
Cc: John G Johnson <john.g.johnson@oracle.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210720125408.387910-5-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Jagannathan Raman <jag.raman@oracle.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Quote docs/devel/style.rst (section "Automatic memory deallocation"):
* Variables declared with g_auto* MUST always be initialized,
otherwise the cleanup function will use uninitialized stack memory
Initialize @name properly to get rid of the compilation error (using
gcc-7.3.0 on CentOS):
../hw/remote/proxy.c: In function 'pci_proxy_dev_realize':
/usr/include/glib-2.0/glib/glib-autocleanups.h:28:3: error: 'name' may be used uninitialized in this function [-Werror=maybe-uninitialized]
g_free (*pp);
^~~~~~~~~~~~
../hw/remote/proxy.c:350:30: note: 'name' was declared here
g_autofree char *name;
^~~~
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Reviewed-by: Jagannathan Raman <jag.raman@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Miroslav Rezanina <mrezanin@redhat.com>
Message-id: 20210312112143.1369-1-yuzenghui@huawei.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Add ProxyMemoryListener object which is used to keep the view of the RAM
in sync between QEMU and remote process.
A MemoryListener is registered for system-memory AddressSpace. The
listener sends SYNC_SYSMEM message to the remote process when memory
listener commits the changes to memory, the remote process receives
the message and processes it in the handler for SYNC_SYSMEM message.
Signed-off-by: Jagannathan Raman <jag.raman@oracle.com>
Signed-off-by: John G Johnson <john.g.johnson@oracle.com>
Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 04fe4e6a9ca90d4f11ab6f59be7652f5b086a071.1611938319.git.jag.raman@oracle.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
