qemu/include/block/nbd.h
Daniel P. Berrange 1c778ef729 nbd: convert to using I/O channels for actual socket I/O
Now that all callers are converted to use I/O channels for
initial connection setup, it is possible to switch the core
NBD protocol handling core over to use QIOChannel APIs for
actual sockets I/O.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-7-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16 17:13:57 +01:00

114 lines
3.7 KiB
C

/*
* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
*
* Network Block Device
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; under version 2 of the License.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#ifndef NBD_H
#define NBD_H
#include <sys/types.h>
#include "qemu-common.h"
#include "qemu/option.h"
#include "io/channel-socket.h"
struct nbd_request {
uint32_t magic;
uint32_t type;
uint64_t handle;
uint64_t from;
uint32_t len;
} QEMU_PACKED;
struct nbd_reply {
uint32_t magic;
uint32_t error;
uint64_t handle;
} QEMU_PACKED;
#define NBD_FLAG_HAS_FLAGS (1 << 0) /* Flags are there */
#define NBD_FLAG_READ_ONLY (1 << 1) /* Device is read-only */
#define NBD_FLAG_SEND_FLUSH (1 << 2) /* Send FLUSH */
#define NBD_FLAG_SEND_FUA (1 << 3) /* Send FUA (Force Unit Access) */
#define NBD_FLAG_ROTATIONAL (1 << 4) /* Use elevator algorithm - rotational media */
#define NBD_FLAG_SEND_TRIM (1 << 5) /* Send TRIM (discard) */
/* New-style global flags. */
#define NBD_FLAG_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */
/* New-style client flags. */
#define NBD_FLAG_C_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */
/* Reply types. */
#define NBD_REP_ACK (1) /* Data sending finished. */
#define NBD_REP_SERVER (2) /* Export description. */
#define NBD_REP_ERR_UNSUP ((UINT32_C(1) << 31) | 1) /* Unknown option. */
#define NBD_REP_ERR_INVALID ((UINT32_C(1) << 31) | 3) /* Invalid length. */
#define NBD_CMD_MASK_COMMAND 0x0000ffff
#define NBD_CMD_FLAG_FUA (1 << 16)
enum {
NBD_CMD_READ = 0,
NBD_CMD_WRITE = 1,
NBD_CMD_DISC = 2,
NBD_CMD_FLUSH = 3,
NBD_CMD_TRIM = 4
};
#define NBD_DEFAULT_PORT 10809
/* Maximum size of a single READ/WRITE data buffer */
#define NBD_MAX_BUFFER_SIZE (32 * 1024 * 1024)
ssize_t nbd_wr_syncv(QIOChannel *ioc,
struct iovec *iov,
size_t niov,
size_t offset,
size_t length,
bool do_read);
int nbd_receive_negotiate(QIOChannel *ioc, const char *name, uint32_t *flags,
off_t *size, Error **errp);
int nbd_init(int fd, QIOChannelSocket *sioc, uint32_t flags, off_t size);
ssize_t nbd_send_request(QIOChannel *ioc, struct nbd_request *request);
ssize_t nbd_receive_reply(QIOChannel *ioc, struct nbd_reply *reply);
int nbd_client(int fd);
int nbd_disconnect(int fd);
typedef struct NBDExport NBDExport;
typedef struct NBDClient NBDClient;
NBDExport *nbd_export_new(BlockBackend *blk, off_t dev_offset, off_t size,
uint32_t nbdflags, void (*close)(NBDExport *),
Error **errp);
void nbd_export_close(NBDExport *exp);
void nbd_export_get(NBDExport *exp);
void nbd_export_put(NBDExport *exp);
BlockBackend *nbd_export_get_blockdev(NBDExport *exp);
NBDExport *nbd_export_find(const char *name);
void nbd_export_set_name(NBDExport *exp, const char *name);
void nbd_export_close_all(void);
void nbd_client_new(NBDExport *exp,
QIOChannelSocket *sioc,
void (*close)(NBDClient *));
void nbd_client_get(NBDClient *client);
void nbd_client_put(NBDClient *client);
#endif