![[BACK]](/cvsweb/icons/back.gif){kind=icon}
Return to nbd.c CVS log ![[TXT]](/cvsweb/icons/text.gif){kind=icon}
![[DIR]](/cvsweb/icons/dir.gif){kind=icon}
Up to [Qemu by Fabrice Bellard] / qemu / block|
Return to nbd.c CVS log | Up to [Qemu by Fabrice Bellard] / qemu / block |
1.1 root 1: /*
2: * QEMU Block driver for NBD
3: *
4: * Copyright (C) 2008 Bull S.A.S.
5: * Author: Laurent Vivier <[email protected]>
6: *
7: * Some parts:
8: * Copyright (C) 2007 Anthony Liguori <[email protected]>
9: *
10: * Permission is hereby granted, free of charge, to any person obtaining a copy
11: * of this software and associated documentation files (the "Software"), to deal
12: * in the Software without restriction, including without limitation the rights
13: * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14: * copies of the Software, and to permit persons to whom the Software is
15: * furnished to do so, subject to the following conditions:
16: *
17: * The above copyright notice and this permission notice shall be included in
18: * all copies or substantial portions of the Software.
19: *
20: * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21: * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22: * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23: * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24: * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25: * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
26: * THE SOFTWARE.
27: */
28:
29: #include "qemu-common.h"
30: #include "nbd.h"
1.1.1.5 ! root 31: #include "block_int.h"
1.1 root 32: #include "module.h"
1.1.1.4 root 33: #include "qemu_socket.h"
1.1 root 34:
35: #include <sys/types.h>
36: #include <unistd.h>
37:
1.1.1.3 root 38: #define EN_OPTSTR ":exportname="
39:
1.1.1.4 root 40: /* #define DEBUG_NBD */
41:
42: #if defined(DEBUG_NBD)
43: #define logout(fmt, ...) \
44: fprintf(stderr, "nbd\t%-24s" fmt, __func__, ##__VA_ARGS__)
45: #else
46: #define logout(fmt, ...) ((void)0)
47: #endif
48:
1.1 root 49: typedef struct BDRVNBDState {
1.1.1.5 ! root 50: CoMutex lock;
1.1 root 51: int sock;
1.1.1.5 ! root 52: uint32_t nbdflags;
1.1 root 53: off_t size;
54: size_t blocksize;
1.1.1.4 root 55: char *export_name; /* An NBD server may export several devices */
56:
57: /* If it begins with '/', this is a UNIX domain socket. Otherwise,
58: * it's a string of the form <hostname|ip4|\[ip6\]>:port
59: */
60: char *host_spec;
1.1 root 61: } BDRVNBDState;
62:
1.1.1.4 root 63: static int nbd_config(BDRVNBDState *s, const char *filename, int flags)
1.1 root 64: {
1.1.1.3 root 65: char *file;
1.1.1.4 root 66: char *export_name;
67: const char *host_spec;
1.1 root 68: const char *unixpath;
1.1.1.3 root 69: int err = -EINVAL;
70:
1.1.1.5 ! root 71: file = g_strdup(filename);
1.1 root 72:
1.1.1.4 root 73: export_name = strstr(file, EN_OPTSTR);
74: if (export_name) {
75: if (export_name[strlen(EN_OPTSTR)] == 0) {
1.1.1.3 root 76: goto out;
77: }
1.1.1.4 root 78: export_name[0] = 0; /* truncate 'file' */
79: export_name += strlen(EN_OPTSTR);
1.1.1.5 ! root 80: s->export_name = g_strdup(export_name);
1.1.1.3 root 81: }
82:
1.1.1.4 root 83: /* extract the host_spec - fail if it's not nbd:... */
84: if (!strstart(file, "nbd:", &host_spec)) {
1.1.1.3 root 85: goto out;
86: }
1.1 root 87:
1.1.1.4 root 88: /* are we a UNIX or TCP socket? */
89: if (strstart(host_spec, "unix:", &unixpath)) {
90: if (unixpath[0] != '/') { /* We demand an absolute path*/
1.1.1.3 root 91: goto out;
92: }
1.1.1.5 ! root 93: s->host_spec = g_strdup(unixpath);
1.1.1.4 root 94: } else {
1.1.1.5 ! root 95: s->host_spec = g_strdup(host_spec);
1.1.1.4 root 96: }
1.1 root 97:
1.1.1.4 root 98: err = 0;
1.1 root 99:
1.1.1.4 root 100: out:
1.1.1.5 ! root 101: g_free(file);
1.1.1.4 root 102: if (err != 0) {
1.1.1.5 ! root 103: g_free(s->export_name);
! 104: g_free(s->host_spec);
1.1.1.4 root 105: }
106: return err;
107: }
1.1 root 108:
1.1.1.4 root 109: static int nbd_establish_connection(BlockDriverState *bs)
110: {
111: BDRVNBDState *s = bs->opaque;
112: int sock;
113: int ret;
114: off_t size;
115: size_t blocksize;
116:
117: if (s->host_spec[0] == '/') {
118: sock = unix_socket_outgoing(s->host_spec);
119: } else {
120: sock = tcp_socket_outgoing_spec(s->host_spec);
1.1 root 121: }
122:
1.1.1.4 root 123: /* Failed to establish connection */
1.1.1.3 root 124: if (sock == -1) {
1.1.1.4 root 125: logout("Failed to establish connection to NBD server\n");
126: return -errno;
1.1.1.3 root 127: }
1.1 root 128:
1.1.1.4 root 129: /* NBD handshake */
1.1.1.5 ! root 130: ret = nbd_receive_negotiate(sock, s->export_name, &s->nbdflags, &size,
1.1.1.4 root 131: &blocksize);
1.1.1.3 root 132: if (ret == -1) {
1.1.1.4 root 133: logout("Failed to negotiate with the NBD server\n");
134: closesocket(sock);
135: return -errno;
1.1.1.3 root 136: }
1.1 root 137:
1.1.1.4 root 138: /* Now that we're connected, set the socket to be non-blocking */
139: socket_set_nonblock(sock);
140:
1.1 root 141: s->sock = sock;
142: s->size = size;
143: s->blocksize = blocksize;
144:
1.1.1.4 root 145: logout("Established connection with NBD server\n");
146: return 0;
147: }
148:
149: static void nbd_teardown_connection(BlockDriverState *bs)
150: {
151: BDRVNBDState *s = bs->opaque;
152: struct nbd_request request;
153:
154: request.type = NBD_CMD_DISC;
155: request.handle = (uint64_t)(intptr_t)bs;
156: request.from = 0;
157: request.len = 0;
158: nbd_send_request(s->sock, &request);
159:
160: closesocket(s->sock);
161: }
162:
163: static int nbd_open(BlockDriverState *bs, const char* filename, int flags)
164: {
165: BDRVNBDState *s = bs->opaque;
166: int result;
167:
168: /* Pop the config into our state object. Exit if invalid. */
169: result = nbd_config(s, filename, flags);
170: if (result != 0) {
171: return result;
172: }
173:
174: /* establish TCP connection, return error if it fails
175: * TODO: Configurable retry-until-timeout behaviour.
176: */
177: result = nbd_establish_connection(bs);
178:
1.1.1.5 ! root 179: qemu_co_mutex_init(&s->lock);
1.1.1.4 root 180: return result;
1.1 root 181: }
182:
183: static int nbd_read(BlockDriverState *bs, int64_t sector_num,
184: uint8_t *buf, int nb_sectors)
185: {
186: BDRVNBDState *s = bs->opaque;
187: struct nbd_request request;
188: struct nbd_reply reply;
189:
190: request.type = NBD_CMD_READ;
191: request.handle = (uint64_t)(intptr_t)bs;
192: request.from = sector_num * 512;;
193: request.len = nb_sectors * 512;
194:
195: if (nbd_send_request(s->sock, &request) == -1)
196: return -errno;
197:
198: if (nbd_receive_reply(s->sock, &reply) == -1)
199: return -errno;
200:
201: if (reply.error !=0)
202: return -reply.error;
203:
204: if (reply.handle != request.handle)
205: return -EIO;
206:
207: if (nbd_wr_sync(s->sock, buf, request.len, 1) != request.len)
208: return -EIO;
209:
210: return 0;
211: }
212:
213: static int nbd_write(BlockDriverState *bs, int64_t sector_num,
214: const uint8_t *buf, int nb_sectors)
215: {
216: BDRVNBDState *s = bs->opaque;
217: struct nbd_request request;
218: struct nbd_reply reply;
219:
220: request.type = NBD_CMD_WRITE;
221: request.handle = (uint64_t)(intptr_t)bs;
222: request.from = sector_num * 512;;
223: request.len = nb_sectors * 512;
224:
225: if (nbd_send_request(s->sock, &request) == -1)
226: return -errno;
227:
228: if (nbd_wr_sync(s->sock, (uint8_t*)buf, request.len, 0) != request.len)
229: return -EIO;
230:
231: if (nbd_receive_reply(s->sock, &reply) == -1)
232: return -errno;
233:
234: if (reply.error !=0)
235: return -reply.error;
236:
237: if (reply.handle != request.handle)
238: return -EIO;
239:
240: return 0;
241: }
242:
1.1.1.5 ! root 243: static coroutine_fn int nbd_co_read(BlockDriverState *bs, int64_t sector_num,
! 244: uint8_t *buf, int nb_sectors)
! 245: {
! 246: int ret;
! 247: BDRVNBDState *s = bs->opaque;
! 248: qemu_co_mutex_lock(&s->lock);
! 249: ret = nbd_read(bs, sector_num, buf, nb_sectors);
! 250: qemu_co_mutex_unlock(&s->lock);
! 251: return ret;
! 252: }
! 253:
! 254: static coroutine_fn int nbd_co_write(BlockDriverState *bs, int64_t sector_num,
! 255: const uint8_t *buf, int nb_sectors)
! 256: {
! 257: int ret;
! 258: BDRVNBDState *s = bs->opaque;
! 259: qemu_co_mutex_lock(&s->lock);
! 260: ret = nbd_write(bs, sector_num, buf, nb_sectors);
! 261: qemu_co_mutex_unlock(&s->lock);
! 262: return ret;
! 263: }
! 264:
1.1 root 265: static void nbd_close(BlockDriverState *bs)
266: {
267: BDRVNBDState *s = bs->opaque;
1.1.1.5 ! root 268: g_free(s->export_name);
! 269: g_free(s->host_spec);
1.1 root 270:
1.1.1.4 root 271: nbd_teardown_connection(bs);
1.1 root 272: }
273:
274: static int64_t nbd_getlength(BlockDriverState *bs)
275: {
276: BDRVNBDState *s = bs->opaque;
277:
278: return s->size;
279: }
280:
281: static BlockDriver bdrv_nbd = {
282: .format_name = "nbd",
283: .instance_size = sizeof(BDRVNBDState),
1.1.1.2 root 284: .bdrv_file_open = nbd_open,
1.1.1.5 ! root 285: .bdrv_read = nbd_co_read,
! 286: .bdrv_write = nbd_co_write,
1.1 root 287: .bdrv_close = nbd_close,
288: .bdrv_getlength = nbd_getlength,
289: .protocol_name = "nbd",
290: };
291:
292: static void bdrv_nbd_init(void)
293: {
294: bdrv_register(&bdrv_nbd);
295: }
296:
297: block_init(bdrv_nbd_init);
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.