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Commit | Line | Data |
---|---|---|
75818250 | 1 | /* |
7a5ca864 FB |
2 | * Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws> |
3 | * | |
4 | * Network Block Device | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; under version 2 of the License. | |
9 | * | |
10 | * This program is distributed in the hope that it will be useful, | |
11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | * GNU General Public License for more details. | |
14 | * | |
15 | * You should have received a copy of the GNU General Public License | |
8167ee88 | 16 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
75818250 | 17 | */ |
7a5ca864 FB |
18 | |
19 | #include "nbd.h" | |
ab359cd1 | 20 | #include "block.h" |
af49bbbe | 21 | #include "block_int.h" |
7a5ca864 | 22 | |
262db388 PB |
23 | #include "qemu-coroutine.h" |
24 | ||
7a5ca864 FB |
25 | #include <errno.h> |
26 | #include <string.h> | |
03ff3ca3 | 27 | #ifndef _WIN32 |
7a5ca864 | 28 | #include <sys/ioctl.h> |
03ff3ca3 | 29 | #endif |
5dc2eec9 | 30 | #if defined(__sun__) || defined(__HAIKU__) |
7e00eb9b AL |
31 | #include <sys/ioccom.h> |
32 | #endif | |
7a5ca864 FB |
33 | #include <ctype.h> |
34 | #include <inttypes.h> | |
75818250 | 35 | |
b90fb4b8 PB |
36 | #ifdef __linux__ |
37 | #include <linux/fs.h> | |
38 | #endif | |
39 | ||
03ff3ca3 | 40 | #include "qemu_socket.h" |
d9a73806 | 41 | #include "qemu-queue.h" |
03ff3ca3 AL |
42 | |
43 | //#define DEBUG_NBD | |
44 | ||
45 | #ifdef DEBUG_NBD | |
75818250 | 46 | #define TRACE(msg, ...) do { \ |
03ff3ca3 | 47 | LOG(msg, ## __VA_ARGS__); \ |
75818250 | 48 | } while(0) |
03ff3ca3 AL |
49 | #else |
50 | #define TRACE(msg, ...) \ | |
51 | do { } while (0) | |
52 | #endif | |
7a5ca864 FB |
53 | |
54 | #define LOG(msg, ...) do { \ | |
55 | fprintf(stderr, "%s:%s():L%d: " msg "\n", \ | |
56 | __FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \ | |
57 | } while(0) | |
58 | ||
7a5ca864 FB |
59 | /* This is all part of the "official" NBD API */ |
60 | ||
b2e3d87f | 61 | #define NBD_REPLY_SIZE (4 + 4 + 8) |
7a5ca864 FB |
62 | #define NBD_REQUEST_MAGIC 0x25609513 |
63 | #define NBD_REPLY_MAGIC 0x67446698 | |
64 | ||
65 | #define NBD_SET_SOCK _IO(0xab, 0) | |
66 | #define NBD_SET_BLKSIZE _IO(0xab, 1) | |
67 | #define NBD_SET_SIZE _IO(0xab, 2) | |
68 | #define NBD_DO_IT _IO(0xab, 3) | |
69 | #define NBD_CLEAR_SOCK _IO(0xab, 4) | |
70 | #define NBD_CLEAR_QUE _IO(0xab, 5) | |
b2e3d87f NT |
71 | #define NBD_PRINT_DEBUG _IO(0xab, 6) |
72 | #define NBD_SET_SIZE_BLOCKS _IO(0xab, 7) | |
7a5ca864 | 73 | #define NBD_DISCONNECT _IO(0xab, 8) |
bbb74edd PB |
74 | #define NBD_SET_TIMEOUT _IO(0xab, 9) |
75 | #define NBD_SET_FLAGS _IO(0xab, 10) | |
7a5ca864 | 76 | |
b2e3d87f | 77 | #define NBD_OPT_EXPORT_NAME (1 << 0) |
1d45f8b5 | 78 | |
7a5ca864 FB |
79 | /* That's all folks */ |
80 | ||
185b4338 | 81 | ssize_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read) |
7a5ca864 FB |
82 | { |
83 | size_t offset = 0; | |
185b4338 | 84 | int err; |
7a5ca864 | 85 | |
ae255e52 PB |
86 | if (qemu_in_coroutine()) { |
87 | if (do_read) { | |
88 | return qemu_co_recv(fd, buffer, size); | |
89 | } else { | |
90 | return qemu_co_send(fd, buffer, size); | |
91 | } | |
92 | } | |
93 | ||
7a5ca864 FB |
94 | while (offset < size) { |
95 | ssize_t len; | |
96 | ||
97 | if (do_read) { | |
00aa0040 | 98 | len = qemu_recv(fd, buffer + offset, size - offset, 0); |
7a5ca864 | 99 | } else { |
03ff3ca3 | 100 | len = send(fd, buffer + offset, size - offset, 0); |
7a5ca864 FB |
101 | } |
102 | ||
fc19f8a0 | 103 | if (len < 0) { |
185b4338 | 104 | err = socket_error(); |
03ff3ca3 | 105 | |
fc19f8a0 | 106 | /* recoverable error */ |
7fe7b68b | 107 | if (err == EINTR || (offset > 0 && err == EAGAIN)) { |
fc19f8a0 PB |
108 | continue; |
109 | } | |
110 | ||
111 | /* unrecoverable error */ | |
185b4338 | 112 | return -err; |
7a5ca864 FB |
113 | } |
114 | ||
115 | /* eof */ | |
116 | if (len == 0) { | |
117 | break; | |
118 | } | |
119 | ||
7a5ca864 FB |
120 | offset += len; |
121 | } | |
122 | ||
123 | return offset; | |
124 | } | |
125 | ||
7fe7b68b PB |
126 | static ssize_t read_sync(int fd, void *buffer, size_t size) |
127 | { | |
128 | /* Sockets are kept in blocking mode in the negotiation phase. After | |
129 | * that, a non-readable socket simply means that another thread stole | |
130 | * our request/reply. Synchronization is done with recv_coroutine, so | |
131 | * that this is coroutine-safe. | |
132 | */ | |
133 | return nbd_wr_sync(fd, buffer, size, true); | |
134 | } | |
135 | ||
136 | static ssize_t write_sync(int fd, void *buffer, size_t size) | |
137 | { | |
138 | int ret; | |
139 | do { | |
140 | /* For writes, we do expect the socket to be writable. */ | |
141 | ret = nbd_wr_sync(fd, buffer, size, false); | |
142 | } while (ret == -EAGAIN); | |
143 | return ret; | |
144 | } | |
145 | ||
c12504ce NT |
146 | static void combine_addr(char *buf, size_t len, const char* address, |
147 | uint16_t port) | |
7a5ca864 | 148 | { |
c12504ce NT |
149 | /* If the address-part contains a colon, it's an IPv6 IP so needs [] */ |
150 | if (strstr(address, ":")) { | |
151 | snprintf(buf, len, "[%s]:%u", address, port); | |
152 | } else { | |
153 | snprintf(buf, len, "%s:%u", address, port); | |
7a5ca864 | 154 | } |
7a5ca864 FB |
155 | } |
156 | ||
c12504ce | 157 | int tcp_socket_outgoing(const char *address, uint16_t port) |
7a5ca864 | 158 | { |
c12504ce NT |
159 | char address_and_port[128]; |
160 | combine_addr(address_and_port, 128, address, port); | |
161 | return tcp_socket_outgoing_spec(address_and_port); | |
7a5ca864 FB |
162 | } |
163 | ||
c12504ce | 164 | int tcp_socket_outgoing_spec(const char *address_and_port) |
cd831bd7 | 165 | { |
c12504ce | 166 | return inet_connect(address_and_port, SOCK_STREAM); |
cd831bd7 TS |
167 | } |
168 | ||
c12504ce | 169 | int tcp_socket_incoming(const char *address, uint16_t port) |
cd831bd7 | 170 | { |
c12504ce NT |
171 | char address_and_port[128]; |
172 | combine_addr(address_and_port, 128, address, port); | |
173 | return tcp_socket_incoming_spec(address_and_port); | |
174 | } | |
cd831bd7 | 175 | |
c12504ce NT |
176 | int tcp_socket_incoming_spec(const char *address_and_port) |
177 | { | |
178 | char *ostr = NULL; | |
179 | int olen = 0; | |
180 | return inet_listen(address_and_port, ostr, olen, SOCK_STREAM, 0); | |
03ff3ca3 | 181 | } |
c12504ce | 182 | |
03ff3ca3 AL |
183 | int unix_socket_incoming(const char *path) |
184 | { | |
c12504ce NT |
185 | char *ostr = NULL; |
186 | int olen = 0; | |
187 | ||
188 | return unix_listen(path, ostr, olen); | |
cd831bd7 TS |
189 | } |
190 | ||
03ff3ca3 AL |
191 | int unix_socket_outgoing(const char *path) |
192 | { | |
c12504ce | 193 | return unix_connect(path); |
03ff3ca3 | 194 | } |
cd831bd7 | 195 | |
7a5ca864 FB |
196 | /* Basic flow |
197 | ||
198 | Server Client | |
199 | ||
200 | Negotiate | |
201 | Request | |
202 | Response | |
203 | Request | |
204 | Response | |
205 | ... | |
206 | ... | |
207 | Request (type == 2) | |
208 | */ | |
209 | ||
af49bbbe | 210 | static int nbd_send_negotiate(int csock, off_t size, uint32_t flags) |
7a5ca864 | 211 | { |
b2e3d87f | 212 | char buf[8 + 8 + 8 + 128]; |
185b4338 | 213 | int rc; |
b2e3d87f NT |
214 | |
215 | /* Negotiate | |
216 | [ 0 .. 7] passwd ("NBDMAGIC") | |
217 | [ 8 .. 15] magic (0x00420281861253) | |
218 | [16 .. 23] size | |
b90fb4b8 PB |
219 | [24 .. 27] flags |
220 | [28 .. 151] reserved (0) | |
b2e3d87f NT |
221 | */ |
222 | ||
7fe7b68b | 223 | socket_set_block(csock); |
185b4338 PB |
224 | rc = -EINVAL; |
225 | ||
b2e3d87f NT |
226 | TRACE("Beginning negotiation."); |
227 | memcpy(buf, "NBDMAGIC", 8); | |
228 | cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL); | |
229 | cpu_to_be64w((uint64_t*)(buf + 16), size); | |
2c7989a9 | 230 | cpu_to_be32w((uint32_t*)(buf + 24), |
7a706633 PB |
231 | flags | NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_TRIM | |
232 | NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA); | |
b90fb4b8 | 233 | memset(buf + 28, 0, 124); |
b2e3d87f NT |
234 | |
235 | if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { | |
236 | LOG("write failed"); | |
185b4338 | 237 | goto fail; |
b2e3d87f NT |
238 | } |
239 | ||
07f35073 | 240 | TRACE("Negotiation succeeded."); |
185b4338 PB |
241 | rc = 0; |
242 | fail: | |
7fe7b68b | 243 | socket_set_nonblock(csock); |
185b4338 | 244 | return rc; |
7a5ca864 FB |
245 | } |
246 | ||
1d45f8b5 LV |
247 | int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, |
248 | off_t *size, size_t *blocksize) | |
7a5ca864 | 249 | { |
b2e3d87f NT |
250 | char buf[256]; |
251 | uint64_t magic, s; | |
252 | uint16_t tmp; | |
185b4338 | 253 | int rc; |
b2e3d87f | 254 | |
07f35073 | 255 | TRACE("Receiving negotiation."); |
b2e3d87f | 256 | |
7fe7b68b | 257 | socket_set_block(csock); |
185b4338 PB |
258 | rc = -EINVAL; |
259 | ||
b2e3d87f NT |
260 | if (read_sync(csock, buf, 8) != 8) { |
261 | LOG("read failed"); | |
185b4338 | 262 | goto fail; |
b2e3d87f NT |
263 | } |
264 | ||
265 | buf[8] = '\0'; | |
266 | if (strlen(buf) == 0) { | |
267 | LOG("server connection closed"); | |
185b4338 | 268 | goto fail; |
b2e3d87f NT |
269 | } |
270 | ||
271 | TRACE("Magic is %c%c%c%c%c%c%c%c", | |
272 | qemu_isprint(buf[0]) ? buf[0] : '.', | |
273 | qemu_isprint(buf[1]) ? buf[1] : '.', | |
274 | qemu_isprint(buf[2]) ? buf[2] : '.', | |
275 | qemu_isprint(buf[3]) ? buf[3] : '.', | |
276 | qemu_isprint(buf[4]) ? buf[4] : '.', | |
277 | qemu_isprint(buf[5]) ? buf[5] : '.', | |
278 | qemu_isprint(buf[6]) ? buf[6] : '.', | |
279 | qemu_isprint(buf[7]) ? buf[7] : '.'); | |
280 | ||
281 | if (memcmp(buf, "NBDMAGIC", 8) != 0) { | |
282 | LOG("Invalid magic received"); | |
185b4338 | 283 | goto fail; |
b2e3d87f NT |
284 | } |
285 | ||
286 | if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { | |
287 | LOG("read failed"); | |
185b4338 | 288 | goto fail; |
b2e3d87f NT |
289 | } |
290 | magic = be64_to_cpu(magic); | |
291 | TRACE("Magic is 0x%" PRIx64, magic); | |
292 | ||
293 | if (name) { | |
294 | uint32_t reserved = 0; | |
295 | uint32_t opt; | |
296 | uint32_t namesize; | |
297 | ||
298 | TRACE("Checking magic (opts_magic)"); | |
299 | if (magic != 0x49484156454F5054LL) { | |
300 | LOG("Bad magic received"); | |
185b4338 | 301 | goto fail; |
b2e3d87f NT |
302 | } |
303 | if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { | |
304 | LOG("flags read failed"); | |
185b4338 | 305 | goto fail; |
b2e3d87f NT |
306 | } |
307 | *flags = be16_to_cpu(tmp) << 16; | |
308 | /* reserved for future use */ | |
309 | if (write_sync(csock, &reserved, sizeof(reserved)) != | |
310 | sizeof(reserved)) { | |
311 | LOG("write failed (reserved)"); | |
185b4338 | 312 | goto fail; |
b2e3d87f NT |
313 | } |
314 | /* write the export name */ | |
315 | magic = cpu_to_be64(magic); | |
316 | if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { | |
317 | LOG("write failed (magic)"); | |
185b4338 | 318 | goto fail; |
b2e3d87f NT |
319 | } |
320 | opt = cpu_to_be32(NBD_OPT_EXPORT_NAME); | |
321 | if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { | |
322 | LOG("write failed (opt)"); | |
185b4338 | 323 | goto fail; |
b2e3d87f NT |
324 | } |
325 | namesize = cpu_to_be32(strlen(name)); | |
326 | if (write_sync(csock, &namesize, sizeof(namesize)) != | |
327 | sizeof(namesize)) { | |
328 | LOG("write failed (namesize)"); | |
185b4338 | 329 | goto fail; |
b2e3d87f NT |
330 | } |
331 | if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) { | |
332 | LOG("write failed (name)"); | |
185b4338 | 333 | goto fail; |
b2e3d87f NT |
334 | } |
335 | } else { | |
336 | TRACE("Checking magic (cli_magic)"); | |
337 | ||
338 | if (magic != 0x00420281861253LL) { | |
339 | LOG("Bad magic received"); | |
185b4338 | 340 | goto fail; |
b2e3d87f NT |
341 | } |
342 | } | |
343 | ||
344 | if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) { | |
345 | LOG("read failed"); | |
185b4338 | 346 | goto fail; |
b2e3d87f NT |
347 | } |
348 | *size = be64_to_cpu(s); | |
349 | *blocksize = 1024; | |
350 | TRACE("Size is %" PRIu64, *size); | |
351 | ||
352 | if (!name) { | |
353 | if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) { | |
354 | LOG("read failed (flags)"); | |
185b4338 | 355 | goto fail; |
b2e3d87f NT |
356 | } |
357 | *flags = be32_to_cpup(flags); | |
358 | } else { | |
359 | if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { | |
360 | LOG("read failed (tmp)"); | |
185b4338 | 361 | goto fail; |
b2e3d87f NT |
362 | } |
363 | *flags |= be32_to_cpu(tmp); | |
364 | } | |
365 | if (read_sync(csock, &buf, 124) != 124) { | |
366 | LOG("read failed (buf)"); | |
185b4338 | 367 | goto fail; |
b2e3d87f | 368 | } |
185b4338 PB |
369 | rc = 0; |
370 | ||
371 | fail: | |
7fe7b68b | 372 | socket_set_nonblock(csock); |
185b4338 | 373 | return rc; |
cd831bd7 | 374 | } |
7a5ca864 | 375 | |
b90fb4b8 PB |
376 | #ifdef __linux__ |
377 | int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize) | |
cd831bd7 | 378 | { |
3e05c785 CL |
379 | TRACE("Setting NBD socket"); |
380 | ||
fc19f8a0 | 381 | if (ioctl(fd, NBD_SET_SOCK, csock) < 0) { |
3e05c785 CL |
382 | int serrno = errno; |
383 | LOG("Failed to set NBD socket"); | |
185b4338 | 384 | return -serrno; |
3e05c785 CL |
385 | } |
386 | ||
b2e3d87f | 387 | TRACE("Setting block size to %lu", (unsigned long)blocksize); |
7a5ca864 | 388 | |
fc19f8a0 | 389 | if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) < 0) { |
b2e3d87f NT |
390 | int serrno = errno; |
391 | LOG("Failed setting NBD block size"); | |
185b4338 | 392 | return -serrno; |
b2e3d87f | 393 | } |
7a5ca864 | 394 | |
0bfcd599 | 395 | TRACE("Setting size to %zd block(s)", (size_t)(size / blocksize)); |
7a5ca864 | 396 | |
fc19f8a0 | 397 | if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) < 0) { |
b2e3d87f NT |
398 | int serrno = errno; |
399 | LOG("Failed setting size (in blocks)"); | |
185b4338 | 400 | return -serrno; |
b2e3d87f | 401 | } |
7a5ca864 | 402 | |
b90fb4b8 PB |
403 | if (flags & NBD_FLAG_READ_ONLY) { |
404 | int read_only = 1; | |
405 | TRACE("Setting readonly attribute"); | |
406 | ||
407 | if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) { | |
408 | int serrno = errno; | |
409 | LOG("Failed setting read-only attribute"); | |
185b4338 | 410 | return -serrno; |
b90fb4b8 PB |
411 | } |
412 | } | |
413 | ||
973b3d0a PB |
414 | if (ioctl(fd, NBD_SET_FLAGS, flags) < 0 |
415 | && errno != ENOTTY) { | |
416 | int serrno = errno; | |
417 | LOG("Failed setting flags"); | |
185b4338 | 418 | return -serrno; |
973b3d0a PB |
419 | } |
420 | ||
b2e3d87f | 421 | TRACE("Negotiation ended"); |
7a5ca864 | 422 | |
b2e3d87f | 423 | return 0; |
7a5ca864 FB |
424 | } |
425 | ||
426 | int nbd_disconnect(int fd) | |
427 | { | |
b2e3d87f NT |
428 | ioctl(fd, NBD_CLEAR_QUE); |
429 | ioctl(fd, NBD_DISCONNECT); | |
430 | ioctl(fd, NBD_CLEAR_SOCK); | |
431 | return 0; | |
7a5ca864 FB |
432 | } |
433 | ||
0a4eb864 | 434 | int nbd_client(int fd) |
7a5ca864 | 435 | { |
b2e3d87f NT |
436 | int ret; |
437 | int serrno; | |
7a5ca864 | 438 | |
b2e3d87f | 439 | TRACE("Doing NBD loop"); |
7a5ca864 | 440 | |
b2e3d87f | 441 | ret = ioctl(fd, NBD_DO_IT); |
fc19f8a0 | 442 | if (ret < 0 && errno == EPIPE) { |
74624688 PB |
443 | /* NBD_DO_IT normally returns EPIPE when someone has disconnected |
444 | * the socket via NBD_DISCONNECT. We do not want to return 1 in | |
445 | * that case. | |
446 | */ | |
447 | ret = 0; | |
448 | } | |
b2e3d87f | 449 | serrno = errno; |
7a5ca864 | 450 | |
b2e3d87f | 451 | TRACE("NBD loop returned %d: %s", ret, strerror(serrno)); |
7a5ca864 | 452 | |
b2e3d87f NT |
453 | TRACE("Clearing NBD queue"); |
454 | ioctl(fd, NBD_CLEAR_QUE); | |
7a5ca864 | 455 | |
b2e3d87f NT |
456 | TRACE("Clearing NBD socket"); |
457 | ioctl(fd, NBD_CLEAR_SOCK); | |
7a5ca864 | 458 | |
b2e3d87f NT |
459 | errno = serrno; |
460 | return ret; | |
7a5ca864 | 461 | } |
03ff3ca3 | 462 | #else |
8e72506e | 463 | int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize) |
03ff3ca3 | 464 | { |
185b4338 | 465 | return -ENOTSUP; |
03ff3ca3 AL |
466 | } |
467 | ||
468 | int nbd_disconnect(int fd) | |
469 | { | |
185b4338 | 470 | return -ENOTSUP; |
03ff3ca3 AL |
471 | } |
472 | ||
0a4eb864 | 473 | int nbd_client(int fd) |
03ff3ca3 | 474 | { |
185b4338 | 475 | return -ENOTSUP; |
03ff3ca3 AL |
476 | } |
477 | #endif | |
7a5ca864 | 478 | |
94e7340b | 479 | ssize_t nbd_send_request(int csock, struct nbd_request *request) |
7a5ca864 | 480 | { |
b2e3d87f | 481 | uint8_t buf[4 + 4 + 8 + 8 + 4]; |
185b4338 | 482 | ssize_t ret; |
b2e3d87f NT |
483 | |
484 | cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC); | |
485 | cpu_to_be32w((uint32_t*)(buf + 4), request->type); | |
486 | cpu_to_be64w((uint64_t*)(buf + 8), request->handle); | |
487 | cpu_to_be64w((uint64_t*)(buf + 16), request->from); | |
488 | cpu_to_be32w((uint32_t*)(buf + 24), request->len); | |
75818250 | 489 | |
b2e3d87f NT |
490 | TRACE("Sending request to client: " |
491 | "{ .from = %" PRIu64", .len = %u, .handle = %" PRIu64", .type=%i}", | |
492 | request->from, request->len, request->handle, request->type); | |
493 | ||
185b4338 PB |
494 | ret = write_sync(csock, buf, sizeof(buf)); |
495 | if (ret < 0) { | |
496 | return ret; | |
497 | } | |
498 | ||
499 | if (ret != sizeof(buf)) { | |
b2e3d87f | 500 | LOG("writing to socket failed"); |
185b4338 | 501 | return -EINVAL; |
b2e3d87f NT |
502 | } |
503 | return 0; | |
504 | } | |
75818250 | 505 | |
94e7340b | 506 | static ssize_t nbd_receive_request(int csock, struct nbd_request *request) |
75818250 | 507 | { |
b2e3d87f NT |
508 | uint8_t buf[4 + 4 + 8 + 8 + 4]; |
509 | uint32_t magic; | |
185b4338 | 510 | ssize_t ret; |
b2e3d87f | 511 | |
185b4338 PB |
512 | ret = read_sync(csock, buf, sizeof(buf)); |
513 | if (ret < 0) { | |
514 | return ret; | |
515 | } | |
516 | ||
517 | if (ret != sizeof(buf)) { | |
b2e3d87f | 518 | LOG("read failed"); |
185b4338 | 519 | return -EINVAL; |
b2e3d87f NT |
520 | } |
521 | ||
522 | /* Request | |
523 | [ 0 .. 3] magic (NBD_REQUEST_MAGIC) | |
524 | [ 4 .. 7] type (0 == READ, 1 == WRITE) | |
525 | [ 8 .. 15] handle | |
526 | [16 .. 23] from | |
527 | [24 .. 27] len | |
528 | */ | |
529 | ||
530 | magic = be32_to_cpup((uint32_t*)buf); | |
531 | request->type = be32_to_cpup((uint32_t*)(buf + 4)); | |
532 | request->handle = be64_to_cpup((uint64_t*)(buf + 8)); | |
533 | request->from = be64_to_cpup((uint64_t*)(buf + 16)); | |
534 | request->len = be32_to_cpup((uint32_t*)(buf + 24)); | |
535 | ||
536 | TRACE("Got request: " | |
537 | "{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }", | |
538 | magic, request->type, request->from, request->len); | |
539 | ||
540 | if (magic != NBD_REQUEST_MAGIC) { | |
541 | LOG("invalid magic (got 0x%x)", magic); | |
185b4338 | 542 | return -EINVAL; |
b2e3d87f NT |
543 | } |
544 | return 0; | |
75818250 TS |
545 | } |
546 | ||
94e7340b | 547 | ssize_t nbd_receive_reply(int csock, struct nbd_reply *reply) |
75818250 | 548 | { |
b2e3d87f NT |
549 | uint8_t buf[NBD_REPLY_SIZE]; |
550 | uint32_t magic; | |
185b4338 | 551 | ssize_t ret; |
b2e3d87f | 552 | |
185b4338 PB |
553 | ret = read_sync(csock, buf, sizeof(buf)); |
554 | if (ret < 0) { | |
555 | return ret; | |
556 | } | |
557 | ||
558 | if (ret != sizeof(buf)) { | |
b2e3d87f | 559 | LOG("read failed"); |
185b4338 | 560 | return -EINVAL; |
b2e3d87f NT |
561 | } |
562 | ||
563 | /* Reply | |
564 | [ 0 .. 3] magic (NBD_REPLY_MAGIC) | |
565 | [ 4 .. 7] error (0 == no error) | |
566 | [ 7 .. 15] handle | |
567 | */ | |
568 | ||
569 | magic = be32_to_cpup((uint32_t*)buf); | |
570 | reply->error = be32_to_cpup((uint32_t*)(buf + 4)); | |
571 | reply->handle = be64_to_cpup((uint64_t*)(buf + 8)); | |
572 | ||
573 | TRACE("Got reply: " | |
574 | "{ magic = 0x%x, .error = %d, handle = %" PRIu64" }", | |
575 | magic, reply->error, reply->handle); | |
576 | ||
577 | if (magic != NBD_REPLY_MAGIC) { | |
578 | LOG("invalid magic (got 0x%x)", magic); | |
185b4338 | 579 | return -EINVAL; |
b2e3d87f NT |
580 | } |
581 | return 0; | |
75818250 TS |
582 | } |
583 | ||
94e7340b | 584 | static ssize_t nbd_send_reply(int csock, struct nbd_reply *reply) |
75818250 | 585 | { |
b2e3d87f | 586 | uint8_t buf[4 + 4 + 8]; |
185b4338 | 587 | ssize_t ret; |
b2e3d87f NT |
588 | |
589 | /* Reply | |
590 | [ 0 .. 3] magic (NBD_REPLY_MAGIC) | |
591 | [ 4 .. 7] error (0 == no error) | |
592 | [ 7 .. 15] handle | |
593 | */ | |
594 | cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC); | |
595 | cpu_to_be32w((uint32_t*)(buf + 4), reply->error); | |
596 | cpu_to_be64w((uint64_t*)(buf + 8), reply->handle); | |
597 | ||
598 | TRACE("Sending response to client"); | |
599 | ||
185b4338 PB |
600 | ret = write_sync(csock, buf, sizeof(buf)); |
601 | if (ret < 0) { | |
602 | return ret; | |
603 | } | |
604 | ||
605 | if (ret != sizeof(buf)) { | |
b2e3d87f | 606 | LOG("writing to socket failed"); |
185b4338 | 607 | return -EINVAL; |
b2e3d87f NT |
608 | } |
609 | return 0; | |
75818250 | 610 | } |
7a5ca864 | 611 | |
41996e38 PB |
612 | #define MAX_NBD_REQUESTS 16 |
613 | ||
d9a73806 PB |
614 | typedef struct NBDRequest NBDRequest; |
615 | ||
616 | struct NBDRequest { | |
617 | QSIMPLEQ_ENTRY(NBDRequest) entry; | |
72deddc5 | 618 | NBDClient *client; |
d9a73806 PB |
619 | uint8_t *data; |
620 | }; | |
621 | ||
af49bbbe PB |
622 | struct NBDExport { |
623 | BlockDriverState *bs; | |
624 | off_t dev_offset; | |
625 | off_t size; | |
af49bbbe | 626 | uint32_t nbdflags; |
d9a73806 | 627 | QSIMPLEQ_HEAD(, NBDRequest) requests; |
af49bbbe PB |
628 | }; |
629 | ||
1743b515 PB |
630 | struct NBDClient { |
631 | int refcount; | |
632 | void (*close)(NBDClient *client); | |
633 | ||
634 | NBDExport *exp; | |
635 | int sock; | |
262db388 PB |
636 | |
637 | Coroutine *recv_coroutine; | |
638 | ||
639 | CoMutex send_lock; | |
640 | Coroutine *send_coroutine; | |
41996e38 PB |
641 | |
642 | int nb_requests; | |
1743b515 PB |
643 | }; |
644 | ||
645 | static void nbd_client_get(NBDClient *client) | |
646 | { | |
647 | client->refcount++; | |
648 | } | |
649 | ||
650 | static void nbd_client_put(NBDClient *client) | |
651 | { | |
652 | if (--client->refcount == 0) { | |
653 | g_free(client); | |
654 | } | |
655 | } | |
656 | ||
657 | static void nbd_client_close(NBDClient *client) | |
658 | { | |
659 | qemu_set_fd_handler2(client->sock, NULL, NULL, NULL, NULL); | |
660 | close(client->sock); | |
661 | client->sock = -1; | |
662 | if (client->close) { | |
663 | client->close(client); | |
664 | } | |
665 | nbd_client_put(client); | |
666 | } | |
667 | ||
72deddc5 | 668 | static NBDRequest *nbd_request_get(NBDClient *client) |
d9a73806 PB |
669 | { |
670 | NBDRequest *req; | |
72deddc5 PB |
671 | NBDExport *exp = client->exp; |
672 | ||
41996e38 PB |
673 | assert(client->nb_requests <= MAX_NBD_REQUESTS - 1); |
674 | client->nb_requests++; | |
675 | ||
d9a73806 PB |
676 | if (QSIMPLEQ_EMPTY(&exp->requests)) { |
677 | req = g_malloc0(sizeof(NBDRequest)); | |
678 | req->data = qemu_blockalign(exp->bs, NBD_BUFFER_SIZE); | |
679 | } else { | |
680 | req = QSIMPLEQ_FIRST(&exp->requests); | |
681 | QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry); | |
682 | } | |
72deddc5 PB |
683 | nbd_client_get(client); |
684 | req->client = client; | |
d9a73806 PB |
685 | return req; |
686 | } | |
687 | ||
72deddc5 | 688 | static void nbd_request_put(NBDRequest *req) |
d9a73806 | 689 | { |
72deddc5 PB |
690 | NBDClient *client = req->client; |
691 | QSIMPLEQ_INSERT_HEAD(&client->exp->requests, req, entry); | |
41996e38 PB |
692 | if (client->nb_requests-- == MAX_NBD_REQUESTS) { |
693 | qemu_notify_event(); | |
694 | } | |
72deddc5 | 695 | nbd_client_put(client); |
d9a73806 PB |
696 | } |
697 | ||
af49bbbe PB |
698 | NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, |
699 | off_t size, uint32_t nbdflags) | |
700 | { | |
701 | NBDExport *exp = g_malloc0(sizeof(NBDExport)); | |
d9a73806 | 702 | QSIMPLEQ_INIT(&exp->requests); |
af49bbbe PB |
703 | exp->bs = bs; |
704 | exp->dev_offset = dev_offset; | |
705 | exp->nbdflags = nbdflags; | |
706 | exp->size = size == -1 ? exp->bs->total_sectors * 512 : size; | |
af49bbbe PB |
707 | return exp; |
708 | } | |
709 | ||
710 | void nbd_export_close(NBDExport *exp) | |
711 | { | |
d9a73806 PB |
712 | while (!QSIMPLEQ_EMPTY(&exp->requests)) { |
713 | NBDRequest *first = QSIMPLEQ_FIRST(&exp->requests); | |
714 | QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry); | |
715 | qemu_vfree(first->data); | |
716 | g_free(first); | |
717 | } | |
718 | ||
af49bbbe PB |
719 | bdrv_close(exp->bs); |
720 | g_free(exp); | |
721 | } | |
722 | ||
41996e38 | 723 | static int nbd_can_read(void *opaque); |
262db388 PB |
724 | static void nbd_read(void *opaque); |
725 | static void nbd_restart_write(void *opaque); | |
726 | ||
94e7340b PB |
727 | static ssize_t nbd_co_send_reply(NBDRequest *req, struct nbd_reply *reply, |
728 | int len) | |
22045592 | 729 | { |
72deddc5 PB |
730 | NBDClient *client = req->client; |
731 | int csock = client->sock; | |
94e7340b | 732 | ssize_t rc, ret; |
22045592 | 733 | |
262db388 | 734 | qemu_co_mutex_lock(&client->send_lock); |
41996e38 PB |
735 | qemu_set_fd_handler2(csock, nbd_can_read, nbd_read, |
736 | nbd_restart_write, client); | |
262db388 PB |
737 | client->send_coroutine = qemu_coroutine_self(); |
738 | ||
22045592 PB |
739 | if (!len) { |
740 | rc = nbd_send_reply(csock, reply); | |
22045592 PB |
741 | } else { |
742 | socket_set_cork(csock, 1); | |
743 | rc = nbd_send_reply(csock, reply); | |
fc19f8a0 | 744 | if (rc >= 0) { |
262db388 | 745 | ret = qemu_co_send(csock, req->data, len); |
22045592 | 746 | if (ret != len) { |
185b4338 | 747 | rc = -EIO; |
22045592 PB |
748 | } |
749 | } | |
22045592 PB |
750 | socket_set_cork(csock, 0); |
751 | } | |
262db388 PB |
752 | |
753 | client->send_coroutine = NULL; | |
41996e38 | 754 | qemu_set_fd_handler2(csock, nbd_can_read, nbd_read, NULL, client); |
262db388 | 755 | qemu_co_mutex_unlock(&client->send_lock); |
22045592 PB |
756 | return rc; |
757 | } | |
758 | ||
94e7340b | 759 | static ssize_t nbd_co_receive_request(NBDRequest *req, struct nbd_request *request) |
a030b347 | 760 | { |
72deddc5 PB |
761 | NBDClient *client = req->client; |
762 | int csock = client->sock; | |
94e7340b | 763 | ssize_t rc; |
a030b347 | 764 | |
262db388 | 765 | client->recv_coroutine = qemu_coroutine_self(); |
7fe7b68b PB |
766 | rc = nbd_receive_request(csock, request); |
767 | if (rc < 0) { | |
768 | if (rc != -EAGAIN) { | |
769 | rc = -EIO; | |
770 | } | |
a030b347 PB |
771 | goto out; |
772 | } | |
773 | ||
774 | if (request->len > NBD_BUFFER_SIZE) { | |
775 | LOG("len (%u) is larger than max len (%u)", | |
776 | request->len, NBD_BUFFER_SIZE); | |
777 | rc = -EINVAL; | |
778 | goto out; | |
779 | } | |
780 | ||
781 | if ((request->from + request->len) < request->from) { | |
782 | LOG("integer overflow detected! " | |
783 | "you're probably being attacked"); | |
784 | rc = -EINVAL; | |
785 | goto out; | |
786 | } | |
787 | ||
788 | TRACE("Decoding type"); | |
789 | ||
790 | if ((request->type & NBD_CMD_MASK_COMMAND) == NBD_CMD_WRITE) { | |
791 | TRACE("Reading %u byte(s)", request->len); | |
792 | ||
262db388 | 793 | if (qemu_co_recv(csock, req->data, request->len) != request->len) { |
a030b347 PB |
794 | LOG("reading from socket failed"); |
795 | rc = -EIO; | |
796 | goto out; | |
797 | } | |
798 | } | |
799 | rc = 0; | |
800 | ||
801 | out: | |
262db388 | 802 | client->recv_coroutine = NULL; |
a030b347 PB |
803 | return rc; |
804 | } | |
805 | ||
262db388 | 806 | static void nbd_trip(void *opaque) |
75818250 | 807 | { |
262db388 | 808 | NBDClient *client = opaque; |
72deddc5 | 809 | NBDRequest *req = nbd_request_get(client); |
1743b515 | 810 | NBDExport *exp = client->exp; |
b2e3d87f NT |
811 | struct nbd_request request; |
812 | struct nbd_reply reply; | |
94e7340b | 813 | ssize_t ret; |
b2e3d87f NT |
814 | |
815 | TRACE("Reading request."); | |
816 | ||
262db388 | 817 | ret = nbd_co_receive_request(req, &request); |
7fe7b68b PB |
818 | if (ret == -EAGAIN) { |
819 | goto done; | |
820 | } | |
a030b347 | 821 | if (ret == -EIO) { |
d9a73806 | 822 | goto out; |
a030b347 | 823 | } |
b2e3d87f | 824 | |
fae69416 PB |
825 | reply.handle = request.handle; |
826 | reply.error = 0; | |
827 | ||
a030b347 PB |
828 | if (ret < 0) { |
829 | reply.error = -ret; | |
830 | goto error_reply; | |
b2e3d87f NT |
831 | } |
832 | ||
af49bbbe | 833 | if ((request.from + request.len) > exp->size) { |
b2e3d87f NT |
834 | LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64 |
835 | ", Offset: %" PRIu64 "\n", | |
af49bbbe | 836 | request.from, request.len, |
0fee8f34 | 837 | (uint64_t)exp->size, (uint64_t)exp->dev_offset); |
b2e3d87f | 838 | LOG("requested operation past EOF--bad client?"); |
fae69416 | 839 | goto invalid_request; |
b2e3d87f NT |
840 | } |
841 | ||
2c7989a9 | 842 | switch (request.type & NBD_CMD_MASK_COMMAND) { |
b2e3d87f NT |
843 | case NBD_CMD_READ: |
844 | TRACE("Request type is READ"); | |
845 | ||
af49bbbe | 846 | ret = bdrv_read(exp->bs, (request.from + exp->dev_offset) / 512, |
d9a73806 | 847 | req->data, request.len / 512); |
adcf6302 | 848 | if (ret < 0) { |
b2e3d87f | 849 | LOG("reading from file failed"); |
adcf6302 | 850 | reply.error = -ret; |
fae69416 | 851 | goto error_reply; |
b2e3d87f | 852 | } |
b2e3d87f NT |
853 | |
854 | TRACE("Read %u byte(s)", request.len); | |
262db388 | 855 | if (nbd_co_send_reply(req, &reply, request.len) < 0) |
d9a73806 | 856 | goto out; |
b2e3d87f NT |
857 | break; |
858 | case NBD_CMD_WRITE: | |
859 | TRACE("Request type is WRITE"); | |
860 | ||
af49bbbe | 861 | if (exp->nbdflags & NBD_FLAG_READ_ONLY) { |
b2e3d87f | 862 | TRACE("Server is read-only, return error"); |
fae69416 PB |
863 | reply.error = EROFS; |
864 | goto error_reply; | |
865 | } | |
866 | ||
867 | TRACE("Writing to device"); | |
868 | ||
af49bbbe | 869 | ret = bdrv_write(exp->bs, (request.from + exp->dev_offset) / 512, |
d9a73806 | 870 | req->data, request.len / 512); |
fae69416 PB |
871 | if (ret < 0) { |
872 | LOG("writing to file failed"); | |
873 | reply.error = -ret; | |
874 | goto error_reply; | |
875 | } | |
b2e3d87f | 876 | |
fae69416 | 877 | if (request.type & NBD_CMD_FLAG_FUA) { |
262db388 | 878 | ret = bdrv_co_flush(exp->bs); |
adcf6302 | 879 | if (ret < 0) { |
fae69416 | 880 | LOG("flush failed"); |
adcf6302 | 881 | reply.error = -ret; |
fae69416 | 882 | goto error_reply; |
2c7989a9 | 883 | } |
b2e3d87f NT |
884 | } |
885 | ||
fc19f8a0 | 886 | if (nbd_co_send_reply(req, &reply, 0) < 0) { |
d9a73806 | 887 | goto out; |
fc19f8a0 | 888 | } |
b2e3d87f NT |
889 | break; |
890 | case NBD_CMD_DISC: | |
891 | TRACE("Request type is DISCONNECT"); | |
892 | errno = 0; | |
262db388 | 893 | goto out; |
1486d04a PB |
894 | case NBD_CMD_FLUSH: |
895 | TRACE("Request type is FLUSH"); | |
896 | ||
262db388 | 897 | ret = bdrv_co_flush(exp->bs); |
1486d04a PB |
898 | if (ret < 0) { |
899 | LOG("flush failed"); | |
900 | reply.error = -ret; | |
901 | } | |
fc19f8a0 | 902 | if (nbd_co_send_reply(req, &reply, 0) < 0) { |
d9a73806 | 903 | goto out; |
fc19f8a0 | 904 | } |
7a706633 PB |
905 | break; |
906 | case NBD_CMD_TRIM: | |
907 | TRACE("Request type is TRIM"); | |
262db388 PB |
908 | ret = bdrv_co_discard(exp->bs, (request.from + exp->dev_offset) / 512, |
909 | request.len / 512); | |
7a706633 PB |
910 | if (ret < 0) { |
911 | LOG("discard failed"); | |
912 | reply.error = -ret; | |
913 | } | |
fc19f8a0 | 914 | if (nbd_co_send_reply(req, &reply, 0) < 0) { |
d9a73806 | 915 | goto out; |
fc19f8a0 | 916 | } |
1486d04a | 917 | break; |
b2e3d87f NT |
918 | default: |
919 | LOG("invalid request type (%u) received", request.type); | |
fae69416 PB |
920 | invalid_request: |
921 | reply.error = -EINVAL; | |
922 | error_reply: | |
fc19f8a0 | 923 | if (nbd_co_send_reply(req, &reply, 0) < 0) { |
d9a73806 | 924 | goto out; |
fc19f8a0 | 925 | } |
fae69416 | 926 | break; |
b2e3d87f NT |
927 | } |
928 | ||
929 | TRACE("Request/Reply complete"); | |
930 | ||
7fe7b68b | 931 | done: |
262db388 PB |
932 | nbd_request_put(req); |
933 | return; | |
934 | ||
d9a73806 | 935 | out: |
72deddc5 | 936 | nbd_request_put(req); |
262db388 | 937 | nbd_client_close(client); |
7a5ca864 | 938 | } |
af49bbbe | 939 | |
41996e38 PB |
940 | static int nbd_can_read(void *opaque) |
941 | { | |
942 | NBDClient *client = opaque; | |
943 | ||
944 | return client->recv_coroutine || client->nb_requests < MAX_NBD_REQUESTS; | |
945 | } | |
946 | ||
1743b515 PB |
947 | static void nbd_read(void *opaque) |
948 | { | |
949 | NBDClient *client = opaque; | |
950 | ||
262db388 PB |
951 | if (client->recv_coroutine) { |
952 | qemu_coroutine_enter(client->recv_coroutine, NULL); | |
953 | } else { | |
954 | qemu_coroutine_enter(qemu_coroutine_create(nbd_trip), client); | |
1743b515 | 955 | } |
1743b515 PB |
956 | } |
957 | ||
262db388 PB |
958 | static void nbd_restart_write(void *opaque) |
959 | { | |
960 | NBDClient *client = opaque; | |
961 | ||
962 | qemu_coroutine_enter(client->send_coroutine, NULL); | |
963 | } | |
964 | ||
1743b515 PB |
965 | NBDClient *nbd_client_new(NBDExport *exp, int csock, |
966 | void (*close)(NBDClient *)) | |
af49bbbe | 967 | { |
1743b515 | 968 | NBDClient *client; |
fc19f8a0 | 969 | if (nbd_send_negotiate(csock, exp->size, exp->nbdflags) < 0) { |
1743b515 PB |
970 | return NULL; |
971 | } | |
972 | client = g_malloc0(sizeof(NBDClient)); | |
973 | client->refcount = 1; | |
974 | client->exp = exp; | |
975 | client->sock = csock; | |
976 | client->close = close; | |
262db388 | 977 | qemu_co_mutex_init(&client->send_lock); |
41996e38 | 978 | qemu_set_fd_handler2(csock, nbd_can_read, nbd_read, NULL, client); |
1743b515 | 979 | return client; |
af49bbbe | 980 | } |