/* * 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", };