vmxnet3: Use common MAC address tracing macros
[qemu.git] / block / nfs.c
1 /*
2 * QEMU Block driver for native access to files on NFS shares
3 *
4 * Copyright (c) 2014 Peter Lieven <pl@kamp.de>
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24
25 #include "qemu/osdep.h"
26
27 #include <poll.h>
28 #include "qemu-common.h"
29 #include "qemu/config-file.h"
30 #include "qemu/error-report.h"
31 #include "qapi/error.h"
32 #include "block/block_int.h"
33 #include "trace.h"
34 #include "qemu/iov.h"
35 #include "qemu/uri.h"
36 #include "qemu/cutils.h"
37 #include "sysemu/sysemu.h"
38 #include <nfsc/libnfs.h>
39
40 #define QEMU_NFS_MAX_READAHEAD_SIZE 1048576
41 #define QEMU_NFS_MAX_DEBUG_LEVEL 2
42
43 typedef struct NFSClient {
44 struct nfs_context *context;
45 struct nfsfh *fh;
46 int events;
47 bool has_zero_init;
48 AioContext *aio_context;
49 blkcnt_t st_blocks;
50 } NFSClient;
51
52 typedef struct NFSRPC {
53 int ret;
54 int complete;
55 QEMUIOVector *iov;
56 struct stat *st;
57 Coroutine *co;
58 QEMUBH *bh;
59 NFSClient *client;
60 } NFSRPC;
61
62 static void nfs_process_read(void *arg);
63 static void nfs_process_write(void *arg);
64
65 static void nfs_set_events(NFSClient *client)
66 {
67 int ev = nfs_which_events(client->context);
68 if (ev != client->events) {
69 aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
70 false,
71 (ev & POLLIN) ? nfs_process_read : NULL,
72 (ev & POLLOUT) ? nfs_process_write : NULL, client);
73
74 }
75 client->events = ev;
76 }
77
78 static void nfs_process_read(void *arg)
79 {
80 NFSClient *client = arg;
81 nfs_service(client->context, POLLIN);
82 nfs_set_events(client);
83 }
84
85 static void nfs_process_write(void *arg)
86 {
87 NFSClient *client = arg;
88 nfs_service(client->context, POLLOUT);
89 nfs_set_events(client);
90 }
91
92 static void nfs_co_init_task(NFSClient *client, NFSRPC *task)
93 {
94 *task = (NFSRPC) {
95 .co = qemu_coroutine_self(),
96 .client = client,
97 };
98 }
99
100 static void nfs_co_generic_bh_cb(void *opaque)
101 {
102 NFSRPC *task = opaque;
103 task->complete = 1;
104 qemu_bh_delete(task->bh);
105 qemu_coroutine_enter(task->co, NULL);
106 }
107
108 static void
109 nfs_co_generic_cb(int ret, struct nfs_context *nfs, void *data,
110 void *private_data)
111 {
112 NFSRPC *task = private_data;
113 task->ret = ret;
114 if (task->ret > 0 && task->iov) {
115 if (task->ret <= task->iov->size) {
116 qemu_iovec_from_buf(task->iov, 0, data, task->ret);
117 } else {
118 task->ret = -EIO;
119 }
120 }
121 if (task->ret == 0 && task->st) {
122 memcpy(task->st, data, sizeof(struct stat));
123 }
124 if (task->ret < 0) {
125 error_report("NFS Error: %s", nfs_get_error(nfs));
126 }
127 if (task->co) {
128 task->bh = aio_bh_new(task->client->aio_context,
129 nfs_co_generic_bh_cb, task);
130 qemu_bh_schedule(task->bh);
131 } else {
132 task->complete = 1;
133 }
134 }
135
136 static int coroutine_fn nfs_co_readv(BlockDriverState *bs,
137 int64_t sector_num, int nb_sectors,
138 QEMUIOVector *iov)
139 {
140 NFSClient *client = bs->opaque;
141 NFSRPC task;
142
143 nfs_co_init_task(client, &task);
144 task.iov = iov;
145
146 if (nfs_pread_async(client->context, client->fh,
147 sector_num * BDRV_SECTOR_SIZE,
148 nb_sectors * BDRV_SECTOR_SIZE,
149 nfs_co_generic_cb, &task) != 0) {
150 return -ENOMEM;
151 }
152
153 while (!task.complete) {
154 nfs_set_events(client);
155 qemu_coroutine_yield();
156 }
157
158 if (task.ret < 0) {
159 return task.ret;
160 }
161
162 /* zero pad short reads */
163 if (task.ret < iov->size) {
164 qemu_iovec_memset(iov, task.ret, 0, iov->size - task.ret);
165 }
166
167 return 0;
168 }
169
170 static int coroutine_fn nfs_co_writev(BlockDriverState *bs,
171 int64_t sector_num, int nb_sectors,
172 QEMUIOVector *iov)
173 {
174 NFSClient *client = bs->opaque;
175 NFSRPC task;
176 char *buf = NULL;
177
178 nfs_co_init_task(client, &task);
179
180 buf = g_try_malloc(nb_sectors * BDRV_SECTOR_SIZE);
181 if (nb_sectors && buf == NULL) {
182 return -ENOMEM;
183 }
184
185 qemu_iovec_to_buf(iov, 0, buf, nb_sectors * BDRV_SECTOR_SIZE);
186
187 if (nfs_pwrite_async(client->context, client->fh,
188 sector_num * BDRV_SECTOR_SIZE,
189 nb_sectors * BDRV_SECTOR_SIZE,
190 buf, nfs_co_generic_cb, &task) != 0) {
191 g_free(buf);
192 return -ENOMEM;
193 }
194
195 while (!task.complete) {
196 nfs_set_events(client);
197 qemu_coroutine_yield();
198 }
199
200 g_free(buf);
201
202 if (task.ret != nb_sectors * BDRV_SECTOR_SIZE) {
203 return task.ret < 0 ? task.ret : -EIO;
204 }
205
206 return 0;
207 }
208
209 static int coroutine_fn nfs_co_flush(BlockDriverState *bs)
210 {
211 NFSClient *client = bs->opaque;
212 NFSRPC task;
213
214 nfs_co_init_task(client, &task);
215
216 if (nfs_fsync_async(client->context, client->fh, nfs_co_generic_cb,
217 &task) != 0) {
218 return -ENOMEM;
219 }
220
221 while (!task.complete) {
222 nfs_set_events(client);
223 qemu_coroutine_yield();
224 }
225
226 return task.ret;
227 }
228
229 /* TODO Convert to fine grained options */
230 static QemuOptsList runtime_opts = {
231 .name = "nfs",
232 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
233 .desc = {
234 {
235 .name = "filename",
236 .type = QEMU_OPT_STRING,
237 .help = "URL to the NFS file",
238 },
239 { /* end of list */ }
240 },
241 };
242
243 static void nfs_detach_aio_context(BlockDriverState *bs)
244 {
245 NFSClient *client = bs->opaque;
246
247 aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
248 false, NULL, NULL, NULL);
249 client->events = 0;
250 }
251
252 static void nfs_attach_aio_context(BlockDriverState *bs,
253 AioContext *new_context)
254 {
255 NFSClient *client = bs->opaque;
256
257 client->aio_context = new_context;
258 nfs_set_events(client);
259 }
260
261 static void nfs_client_close(NFSClient *client)
262 {
263 if (client->context) {
264 if (client->fh) {
265 nfs_close(client->context, client->fh);
266 }
267 aio_set_fd_handler(client->aio_context, nfs_get_fd(client->context),
268 false, NULL, NULL, NULL);
269 nfs_destroy_context(client->context);
270 }
271 memset(client, 0, sizeof(NFSClient));
272 }
273
274 static void nfs_file_close(BlockDriverState *bs)
275 {
276 NFSClient *client = bs->opaque;
277 nfs_client_close(client);
278 }
279
280 static int64_t nfs_client_open(NFSClient *client, const char *filename,
281 int flags, Error **errp)
282 {
283 int ret = -EINVAL, i;
284 struct stat st;
285 URI *uri;
286 QueryParams *qp = NULL;
287 char *file = NULL, *strp = NULL;
288
289 uri = uri_parse(filename);
290 if (!uri) {
291 error_setg(errp, "Invalid URL specified");
292 goto fail;
293 }
294 if (!uri->server) {
295 error_setg(errp, "Invalid URL specified");
296 goto fail;
297 }
298 strp = strrchr(uri->path, '/');
299 if (strp == NULL) {
300 error_setg(errp, "Invalid URL specified");
301 goto fail;
302 }
303 file = g_strdup(strp);
304 *strp = 0;
305
306 client->context = nfs_init_context();
307 if (client->context == NULL) {
308 error_setg(errp, "Failed to init NFS context");
309 goto fail;
310 }
311
312 qp = query_params_parse(uri->query);
313 for (i = 0; i < qp->n; i++) {
314 unsigned long long val;
315 if (!qp->p[i].value) {
316 error_setg(errp, "Value for NFS parameter expected: %s",
317 qp->p[i].name);
318 goto fail;
319 }
320 if (parse_uint_full(qp->p[i].value, &val, 0)) {
321 error_setg(errp, "Illegal value for NFS parameter: %s",
322 qp->p[i].name);
323 goto fail;
324 }
325 if (!strcmp(qp->p[i].name, "uid")) {
326 nfs_set_uid(client->context, val);
327 } else if (!strcmp(qp->p[i].name, "gid")) {
328 nfs_set_gid(client->context, val);
329 } else if (!strcmp(qp->p[i].name, "tcp-syncnt")) {
330 nfs_set_tcp_syncnt(client->context, val);
331 #ifdef LIBNFS_FEATURE_READAHEAD
332 } else if (!strcmp(qp->p[i].name, "readahead")) {
333 if (val > QEMU_NFS_MAX_READAHEAD_SIZE) {
334 error_report("NFS Warning: Truncating NFS readahead"
335 " size to %d", QEMU_NFS_MAX_READAHEAD_SIZE);
336 val = QEMU_NFS_MAX_READAHEAD_SIZE;
337 }
338 nfs_set_readahead(client->context, val);
339 #endif
340 #ifdef LIBNFS_FEATURE_DEBUG
341 } else if (!strcmp(qp->p[i].name, "debug")) {
342 /* limit the maximum debug level to avoid potential flooding
343 * of our log files. */
344 if (val > QEMU_NFS_MAX_DEBUG_LEVEL) {
345 error_report("NFS Warning: Limiting NFS debug level"
346 " to %d", QEMU_NFS_MAX_DEBUG_LEVEL);
347 val = QEMU_NFS_MAX_DEBUG_LEVEL;
348 }
349 nfs_set_debug(client->context, val);
350 #endif
351 } else {
352 error_setg(errp, "Unknown NFS parameter name: %s",
353 qp->p[i].name);
354 goto fail;
355 }
356 }
357
358 ret = nfs_mount(client->context, uri->server, uri->path);
359 if (ret < 0) {
360 error_setg(errp, "Failed to mount nfs share: %s",
361 nfs_get_error(client->context));
362 goto fail;
363 }
364
365 if (flags & O_CREAT) {
366 ret = nfs_creat(client->context, file, 0600, &client->fh);
367 if (ret < 0) {
368 error_setg(errp, "Failed to create file: %s",
369 nfs_get_error(client->context));
370 goto fail;
371 }
372 } else {
373 ret = nfs_open(client->context, file, flags, &client->fh);
374 if (ret < 0) {
375 error_setg(errp, "Failed to open file : %s",
376 nfs_get_error(client->context));
377 goto fail;
378 }
379 }
380
381 ret = nfs_fstat(client->context, client->fh, &st);
382 if (ret < 0) {
383 error_setg(errp, "Failed to fstat file: %s",
384 nfs_get_error(client->context));
385 goto fail;
386 }
387
388 ret = DIV_ROUND_UP(st.st_size, BDRV_SECTOR_SIZE);
389 client->st_blocks = st.st_blocks;
390 client->has_zero_init = S_ISREG(st.st_mode);
391 goto out;
392 fail:
393 nfs_client_close(client);
394 out:
395 if (qp) {
396 query_params_free(qp);
397 }
398 uri_free(uri);
399 g_free(file);
400 return ret;
401 }
402
403 static int nfs_file_open(BlockDriverState *bs, QDict *options, int flags,
404 Error **errp) {
405 NFSClient *client = bs->opaque;
406 int64_t ret;
407 QemuOpts *opts;
408 Error *local_err = NULL;
409
410 client->aio_context = bdrv_get_aio_context(bs);
411
412 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
413 qemu_opts_absorb_qdict(opts, options, &local_err);
414 if (local_err) {
415 error_propagate(errp, local_err);
416 ret = -EINVAL;
417 goto out;
418 }
419 ret = nfs_client_open(client, qemu_opt_get(opts, "filename"),
420 (flags & BDRV_O_RDWR) ? O_RDWR : O_RDONLY,
421 errp);
422 if (ret < 0) {
423 goto out;
424 }
425 bs->total_sectors = ret;
426 ret = 0;
427 out:
428 qemu_opts_del(opts);
429 return ret;
430 }
431
432 static QemuOptsList nfs_create_opts = {
433 .name = "nfs-create-opts",
434 .head = QTAILQ_HEAD_INITIALIZER(nfs_create_opts.head),
435 .desc = {
436 {
437 .name = BLOCK_OPT_SIZE,
438 .type = QEMU_OPT_SIZE,
439 .help = "Virtual disk size"
440 },
441 { /* end of list */ }
442 }
443 };
444
445 static int nfs_file_create(const char *url, QemuOpts *opts, Error **errp)
446 {
447 int ret = 0;
448 int64_t total_size = 0;
449 NFSClient *client = g_new0(NFSClient, 1);
450
451 client->aio_context = qemu_get_aio_context();
452
453 /* Read out options */
454 total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
455 BDRV_SECTOR_SIZE);
456
457 ret = nfs_client_open(client, url, O_CREAT, errp);
458 if (ret < 0) {
459 goto out;
460 }
461 ret = nfs_ftruncate(client->context, client->fh, total_size);
462 nfs_client_close(client);
463 out:
464 g_free(client);
465 return ret;
466 }
467
468 static int nfs_has_zero_init(BlockDriverState *bs)
469 {
470 NFSClient *client = bs->opaque;
471 return client->has_zero_init;
472 }
473
474 static int64_t nfs_get_allocated_file_size(BlockDriverState *bs)
475 {
476 NFSClient *client = bs->opaque;
477 NFSRPC task = {0};
478 struct stat st;
479
480 if (bdrv_is_read_only(bs) &&
481 !(bs->open_flags & BDRV_O_NOCACHE)) {
482 return client->st_blocks * 512;
483 }
484
485 task.st = &st;
486 if (nfs_fstat_async(client->context, client->fh, nfs_co_generic_cb,
487 &task) != 0) {
488 return -ENOMEM;
489 }
490
491 while (!task.complete) {
492 nfs_set_events(client);
493 aio_poll(client->aio_context, true);
494 }
495
496 return (task.ret < 0 ? task.ret : st.st_blocks * 512);
497 }
498
499 static int nfs_file_truncate(BlockDriverState *bs, int64_t offset)
500 {
501 NFSClient *client = bs->opaque;
502 return nfs_ftruncate(client->context, client->fh, offset);
503 }
504
505 /* Note that this will not re-establish a connection with the NFS server
506 * - it is effectively a NOP. */
507 static int nfs_reopen_prepare(BDRVReopenState *state,
508 BlockReopenQueue *queue, Error **errp)
509 {
510 NFSClient *client = state->bs->opaque;
511 struct stat st;
512 int ret = 0;
513
514 if (state->flags & BDRV_O_RDWR && bdrv_is_read_only(state->bs)) {
515 error_setg(errp, "Cannot open a read-only mount as read-write");
516 return -EACCES;
517 }
518
519 /* Update cache for read-only reopens */
520 if (!(state->flags & BDRV_O_RDWR)) {
521 ret = nfs_fstat(client->context, client->fh, &st);
522 if (ret < 0) {
523 error_setg(errp, "Failed to fstat file: %s",
524 nfs_get_error(client->context));
525 return ret;
526 }
527 client->st_blocks = st.st_blocks;
528 }
529
530 return 0;
531 }
532
533 static BlockDriver bdrv_nfs = {
534 .format_name = "nfs",
535 .protocol_name = "nfs",
536
537 .instance_size = sizeof(NFSClient),
538 .bdrv_needs_filename = true,
539 .create_opts = &nfs_create_opts,
540
541 .bdrv_has_zero_init = nfs_has_zero_init,
542 .bdrv_get_allocated_file_size = nfs_get_allocated_file_size,
543 .bdrv_truncate = nfs_file_truncate,
544
545 .bdrv_file_open = nfs_file_open,
546 .bdrv_close = nfs_file_close,
547 .bdrv_create = nfs_file_create,
548 .bdrv_reopen_prepare = nfs_reopen_prepare,
549
550 .bdrv_co_readv = nfs_co_readv,
551 .bdrv_co_writev = nfs_co_writev,
552 .bdrv_co_flush_to_disk = nfs_co_flush,
553
554 .bdrv_detach_aio_context = nfs_detach_aio_context,
555 .bdrv_attach_aio_context = nfs_attach_aio_context,
556 };
557
558 static void nfs_block_init(void)
559 {
560 bdrv_register(&bdrv_nfs);
561 }
562
563 block_init(nfs_block_init);