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/*
* QEMU Block driver for NBD
*
* Copyright (C) 2008 Bull S.A.S.
* Author: Laurent Vivier <Laurent.Vivier@bull.net>
*
* Some parts:
* Copyright (C) 2007 Anthony Liguori <anthony@codemonkey.ws>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu-common.h"
#include "nbd.h"
#include <sys/types.h>
#include <unistd.h>
typedef struct BDRVNBDState {
int sock;
off_t size;
size_t blocksize;
} BDRVNBDState;
static int nbd_open(BlockDriverState *bs, const char* filename, int flags)
{
BDRVNBDState *s = bs->opaque;
const char *host;
const char *unixpath;
int sock;
off_t size;
size_t blocksize;
int ret;
if ((flags & BDRV_O_CREAT))
return -EINVAL;
if (!strstart(filename, "nbd:", &host))
return -EINVAL;
if (strstart(host, "unix:", &unixpath)) {
if (unixpath[0] != '/')
return -EINVAL;
sock = unix_socket_outgoing(unixpath);
} else {
uint16_t port;
char *p, *r;
char hostname[128];
pstrcpy(hostname, 128, host);
p = strchr(hostname, ':');
if (p == NULL)
return -EINVAL;
*p = '\0';
p++;
port = strtol(p, &r, 0);
if (r == p)
return -EINVAL;
sock = tcp_socket_outgoing(hostname, port);
}
if (sock == -1)
return -errno;
ret = nbd_receive_negotiate(sock, &size, &blocksize);
if (ret == -1)
return -errno;
s->sock = sock;
s->size = size;
s->blocksize = blocksize;
return 0;
}
static int nbd_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
{
BDRVNBDState *s = bs->opaque;
struct nbd_request request;
struct nbd_reply reply;
request.type = NBD_CMD_READ;
request.handle = (uint64_t)(intptr_t)bs;
request.from = sector_num * 512;;
request.len = nb_sectors * 512;
if (nbd_send_request(s->sock, &request) == -1)
return -errno;
if (nbd_receive_reply(s->sock, &reply) == -1)
return -errno;
if (reply.error !=0)
return -reply.error;
if (reply.handle != request.handle)
return -EIO;
if (nbd_wr_sync(s->sock, buf, request.len, 1) != request.len)
return -EIO;
return 0;
}
static int nbd_write(BlockDriverState *bs, int64_t sector_num,
const uint8_t *buf, int nb_sectors)
{
BDRVNBDState *s = bs->opaque;
struct nbd_request request;
struct nbd_reply reply;
request.type = NBD_CMD_WRITE;
request.handle = (uint64_t)(intptr_t)bs;
request.from = sector_num * 512;;
request.len = nb_sectors * 512;
if (nbd_send_request(s->sock, &request) == -1)
return -errno;
if (nbd_wr_sync(s->sock, (uint8_t*)buf, request.len, 0) != request.len)
return -EIO;
if (nbd_receive_reply(s->sock, &reply) == -1)
return -errno;
if (reply.error !=0)
return -reply.error;
if (reply.handle != request.handle)
return -EIO;
return 0;
}
static void nbd_close(BlockDriverState *bs)
{
BDRVNBDState *s = bs->opaque;
struct nbd_request request;
request.type = NBD_CMD_DISC;
request.handle = (uint64_t)(intptr_t)bs;
request.from = 0;
request.len = 0;
nbd_send_request(s->sock, &request);
close(s->sock);
}
static int64_t nbd_getlength(BlockDriverState *bs)
{
BDRVNBDState *s = bs->opaque;
return s->size;
}
BlockDriver bdrv_nbd = {
.format_name = "nbd",
.instance_size = sizeof(BDRVNBDState),
.bdrv_open = nbd_open,
.bdrv_read = nbd_read,
.bdrv_write = nbd_write,
.bdrv_close = nbd_close,
.bdrv_getlength = nbd_getlength,
.protocol_name = "nbd",
};
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