mirror of
https://github.com/xemu-project/xemu.git
synced 2024-11-23 19:49:43 +00:00
2b556518c3
The NBD server already used to send a FUA flag when the writethrough mode was set. This code was a remnant from the times where protocol drivers actually had to implement writethrough modes. Since nowadays the block layer sends flushes in writethrough mode and non-root nodes are always writeback, this was mostly dead code - only mostly because if NBD was configured to be used without a format, we sent _both_ FUA and an explicit flush afterwards, which makes the code not technically dead, but useless overhead. This patch changes the code so that the block layer's FUA flag is recognised and translated into a NBD FUA flag. The additional flush is avoided now. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Max Reitz <mreitz@redhat.com>
60 lines
1.7 KiB
C
60 lines
1.7 KiB
C
#ifndef NBD_CLIENT_H
|
|
#define NBD_CLIENT_H
|
|
|
|
#include "qemu-common.h"
|
|
#include "block/nbd.h"
|
|
#include "block/block_int.h"
|
|
#include "io/channel-socket.h"
|
|
|
|
/* #define DEBUG_NBD */
|
|
|
|
#if defined(DEBUG_NBD)
|
|
#define logout(fmt, ...) \
|
|
fprintf(stderr, "nbd\t%-24s" fmt, __func__, ##__VA_ARGS__)
|
|
#else
|
|
#define logout(fmt, ...) ((void)0)
|
|
#endif
|
|
|
|
#define MAX_NBD_REQUESTS 16
|
|
|
|
typedef struct NbdClientSession {
|
|
QIOChannelSocket *sioc; /* The master data channel */
|
|
QIOChannel *ioc; /* The current I/O channel which may differ (eg TLS) */
|
|
uint32_t nbdflags;
|
|
off_t size;
|
|
|
|
CoMutex send_mutex;
|
|
CoMutex free_sema;
|
|
Coroutine *send_coroutine;
|
|
int in_flight;
|
|
|
|
Coroutine *recv_coroutine[MAX_NBD_REQUESTS];
|
|
struct nbd_reply reply;
|
|
|
|
bool is_unix;
|
|
} NbdClientSession;
|
|
|
|
NbdClientSession *nbd_get_client_session(BlockDriverState *bs);
|
|
|
|
int nbd_client_init(BlockDriverState *bs,
|
|
QIOChannelSocket *sock,
|
|
const char *export_name,
|
|
QCryptoTLSCreds *tlscreds,
|
|
const char *hostname,
|
|
Error **errp);
|
|
void nbd_client_close(BlockDriverState *bs);
|
|
|
|
int nbd_client_co_discard(BlockDriverState *bs, int64_t sector_num,
|
|
int nb_sectors);
|
|
int nbd_client_co_flush(BlockDriverState *bs);
|
|
int nbd_client_co_writev(BlockDriverState *bs, int64_t sector_num,
|
|
int nb_sectors, QEMUIOVector *qiov, int *flags);
|
|
int nbd_client_co_readv(BlockDriverState *bs, int64_t sector_num,
|
|
int nb_sectors, QEMUIOVector *qiov);
|
|
|
|
void nbd_client_detach_aio_context(BlockDriverState *bs);
|
|
void nbd_client_attach_aio_context(BlockDriverState *bs,
|
|
AioContext *new_context);
|
|
|
|
#endif /* NBD_CLIENT_H */
|