qemu-e2k/hw/remote
Leonardo Bras b88651cb4d QIOChannel: Add flags on io_writev and introduce io_flush callback
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>
2022-05-16 13:56:24 +01:00
..
Kconfig
iohub.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
machine.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
memory.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
meson.build multi-process: create IOHUB object to handle irq 2021-02-10 09:23:28 +00:00
message.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
mpqemu-link.c QIOChannel: Add flags on io_writev and introduce io_flush callback 2022-05-16 13:56:24 +01:00
proxy-memory-listener.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
proxy.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
remote-obj.c Remove qemu-common.h include from most units 2022-04-06 14:31:55 +02:00
trace-events multi-process: define MPQemuMsg format and transmission functions 2021-02-10 09:23:28 +00:00
trace.h multi-process: define MPQemuMsg format and transmission functions 2021-02-10 09:23:28 +00:00