diff options
Diffstat (limited to 'block/nbd.c')
| -rw-r--r-- | block/nbd.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/block/nbd.c b/block/nbd.c new file mode 100644 index 0000000..47d4778 --- /dev/null +++ b/block/nbd.c @@ -0,0 +1,196 @@ +/* + * 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 "module.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; +} + +static 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", +}; + +static void bdrv_nbd_init(void) +{ + bdrv_register(&bdrv_nbd); +} + +block_init(bdrv_nbd_init); |