qemu/block/nbd-client.h
Daniel P. Berrange 064097d919 nbd: convert block client to use I/O channels for connection setup
This converts the NBD block driver client to use the QIOChannelSocket
class for initial connection setup. The NbdClientSession struct has
two pointers, one to the master QIOChannelSocket providing the raw
data channel, and one to a QIOChannel which is the current channel
used for I/O. Initially the two point to the same object, but when
TLS support is added, they will point to different objects.

The qemu-img & qemu-io tools now need to use MODULE_INIT_QOM to
ensure the QIOChannel object classes are registered. The qemu-nbd
tool already did this.

In this initial conversion though, all I/O is still actually done
using the raw POSIX sockets APIs.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-4-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16 17:13:22 +01:00

58 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,
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 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 */