Merge remote-tracking branch 'remotes/kraxel/tags/pull-vga-20170103-1' into staging
[qemu.git] / block / rbd.c
1 /*
2 * QEMU Block driver for RADOS (Ceph)
3 *
4 * Copyright (C) 2010-2011 Christian Brunner <chb@muc.de>,
5 * Josh Durgin <josh.durgin@dreamhost.com>
6 *
7 * This work is licensed under the terms of the GNU GPL, version 2. See
8 * the COPYING file in the top-level directory.
9 *
10 * Contributions after 2012-01-13 are licensed under the terms of the
11 * GNU GPL, version 2 or (at your option) any later version.
12 */
13
14 #include "qemu/osdep.h"
15
16 #include "qapi/error.h"
17 #include "qemu/error-report.h"
18 #include "block/block_int.h"
19 #include "crypto/secret.h"
20 #include "qemu/cutils.h"
21
22 #include <rbd/librbd.h>
23
24 /*
25 * When specifying the image filename use:
26 *
27 * rbd:poolname/devicename[@snapshotname][:option1=value1[:option2=value2...]]
28 *
29 * poolname must be the name of an existing rados pool.
30 *
31 * devicename is the name of the rbd image.
32 *
33 * Each option given is used to configure rados, and may be any valid
34 * Ceph option, "id", or "conf".
35 *
36 * The "id" option indicates what user we should authenticate as to
37 * the Ceph cluster. If it is excluded we will use the Ceph default
38 * (normally 'admin').
39 *
40 * The "conf" option specifies a Ceph configuration file to read. If
41 * it is not specified, we will read from the default Ceph locations
42 * (e.g., /etc/ceph/ceph.conf). To avoid reading _any_ configuration
43 * file, specify conf=/dev/null.
44 *
45 * Configuration values containing :, @, or = can be escaped with a
46 * leading "\".
47 */
48
49 /* rbd_aio_discard added in 0.1.2 */
50 #if LIBRBD_VERSION_CODE >= LIBRBD_VERSION(0, 1, 2)
51 #define LIBRBD_SUPPORTS_DISCARD
52 #else
53 #undef LIBRBD_SUPPORTS_DISCARD
54 #endif
55
56 #define OBJ_MAX_SIZE (1UL << OBJ_DEFAULT_OBJ_ORDER)
57
58 #define RBD_MAX_CONF_NAME_SIZE 128
59 #define RBD_MAX_CONF_VAL_SIZE 512
60 #define RBD_MAX_CONF_SIZE 1024
61 #define RBD_MAX_POOL_NAME_SIZE 128
62 #define RBD_MAX_SNAP_NAME_SIZE 128
63 #define RBD_MAX_SNAPS 100
64
65 typedef enum {
66 RBD_AIO_READ,
67 RBD_AIO_WRITE,
68 RBD_AIO_DISCARD,
69 RBD_AIO_FLUSH
70 } RBDAIOCmd;
71
72 typedef struct RBDAIOCB {
73 BlockAIOCB common;
74 int64_t ret;
75 QEMUIOVector *qiov;
76 char *bounce;
77 RBDAIOCmd cmd;
78 int error;
79 struct BDRVRBDState *s;
80 } RBDAIOCB;
81
82 typedef struct RADOSCB {
83 RBDAIOCB *acb;
84 struct BDRVRBDState *s;
85 int64_t size;
86 char *buf;
87 int64_t ret;
88 } RADOSCB;
89
90 typedef struct BDRVRBDState {
91 rados_t cluster;
92 rados_ioctx_t io_ctx;
93 rbd_image_t image;
94 char name[RBD_MAX_IMAGE_NAME_SIZE];
95 char *snap;
96 } BDRVRBDState;
97
98 static int qemu_rbd_next_tok(char *dst, int dst_len,
99 char *src, char delim,
100 const char *name,
101 char **p, Error **errp)
102 {
103 int l;
104 char *end;
105
106 *p = NULL;
107
108 if (delim != '\0') {
109 for (end = src; *end; ++end) {
110 if (*end == delim) {
111 break;
112 }
113 if (*end == '\\' && end[1] != '\0') {
114 end++;
115 }
116 }
117 if (*end == delim) {
118 *p = end + 1;
119 *end = '\0';
120 }
121 }
122 l = strlen(src);
123 if (l >= dst_len) {
124 error_setg(errp, "%s too long", name);
125 return -EINVAL;
126 } else if (l == 0) {
127 error_setg(errp, "%s too short", name);
128 return -EINVAL;
129 }
130
131 pstrcpy(dst, dst_len, src);
132
133 return 0;
134 }
135
136 static void qemu_rbd_unescape(char *src)
137 {
138 char *p;
139
140 for (p = src; *src; ++src, ++p) {
141 if (*src == '\\' && src[1] != '\0') {
142 src++;
143 }
144 *p = *src;
145 }
146 *p = '\0';
147 }
148
149 static int qemu_rbd_parsename(const char *filename,
150 char *pool, int pool_len,
151 char *snap, int snap_len,
152 char *name, int name_len,
153 char *conf, int conf_len,
154 Error **errp)
155 {
156 const char *start;
157 char *p, *buf;
158 int ret;
159
160 if (!strstart(filename, "rbd:", &start)) {
161 error_setg(errp, "File name must start with 'rbd:'");
162 return -EINVAL;
163 }
164
165 buf = g_strdup(start);
166 p = buf;
167 *snap = '\0';
168 *conf = '\0';
169
170 ret = qemu_rbd_next_tok(pool, pool_len, p,
171 '/', "pool name", &p, errp);
172 if (ret < 0 || !p) {
173 ret = -EINVAL;
174 goto done;
175 }
176 qemu_rbd_unescape(pool);
177
178 if (strchr(p, '@')) {
179 ret = qemu_rbd_next_tok(name, name_len, p,
180 '@', "object name", &p, errp);
181 if (ret < 0) {
182 goto done;
183 }
184 ret = qemu_rbd_next_tok(snap, snap_len, p,
185 ':', "snap name", &p, errp);
186 qemu_rbd_unescape(snap);
187 } else {
188 ret = qemu_rbd_next_tok(name, name_len, p,
189 ':', "object name", &p, errp);
190 }
191 qemu_rbd_unescape(name);
192 if (ret < 0 || !p) {
193 goto done;
194 }
195
196 ret = qemu_rbd_next_tok(conf, conf_len, p,
197 '\0', "configuration", &p, errp);
198
199 done:
200 g_free(buf);
201 return ret;
202 }
203
204 static char *qemu_rbd_parse_clientname(const char *conf, char *clientname)
205 {
206 const char *p = conf;
207
208 while (*p) {
209 int len;
210 const char *end = strchr(p, ':');
211
212 if (end) {
213 len = end - p;
214 } else {
215 len = strlen(p);
216 }
217
218 if (strncmp(p, "id=", 3) == 0) {
219 len -= 3;
220 strncpy(clientname, p + 3, len);
221 clientname[len] = '\0';
222 return clientname;
223 }
224 if (end == NULL) {
225 break;
226 }
227 p = end + 1;
228 }
229 return NULL;
230 }
231
232
233 static int qemu_rbd_set_auth(rados_t cluster, const char *secretid,
234 Error **errp)
235 {
236 if (secretid == 0) {
237 return 0;
238 }
239
240 gchar *secret = qcrypto_secret_lookup_as_base64(secretid,
241 errp);
242 if (!secret) {
243 return -1;
244 }
245
246 rados_conf_set(cluster, "key", secret);
247 g_free(secret);
248
249 return 0;
250 }
251
252
253 static int qemu_rbd_set_conf(rados_t cluster, const char *conf,
254 bool only_read_conf_file,
255 Error **errp)
256 {
257 char *p, *buf;
258 char name[RBD_MAX_CONF_NAME_SIZE];
259 char value[RBD_MAX_CONF_VAL_SIZE];
260 int ret = 0;
261
262 buf = g_strdup(conf);
263 p = buf;
264
265 while (p) {
266 ret = qemu_rbd_next_tok(name, sizeof(name), p,
267 '=', "conf option name", &p, errp);
268 if (ret < 0) {
269 break;
270 }
271 qemu_rbd_unescape(name);
272
273 if (!p) {
274 error_setg(errp, "conf option %s has no value", name);
275 ret = -EINVAL;
276 break;
277 }
278
279 ret = qemu_rbd_next_tok(value, sizeof(value), p,
280 ':', "conf option value", &p, errp);
281 if (ret < 0) {
282 break;
283 }
284 qemu_rbd_unescape(value);
285
286 if (strcmp(name, "conf") == 0) {
287 /* read the conf file alone, so it doesn't override more
288 specific settings for a particular device */
289 if (only_read_conf_file) {
290 ret = rados_conf_read_file(cluster, value);
291 if (ret < 0) {
292 error_setg_errno(errp, -ret, "error reading conf file %s",
293 value);
294 break;
295 }
296 }
297 } else if (strcmp(name, "id") == 0) {
298 /* ignore, this is parsed by qemu_rbd_parse_clientname() */
299 } else if (!only_read_conf_file) {
300 ret = rados_conf_set(cluster, name, value);
301 if (ret < 0) {
302 error_setg_errno(errp, -ret, "invalid conf option %s", name);
303 ret = -EINVAL;
304 break;
305 }
306 }
307 }
308
309 g_free(buf);
310 return ret;
311 }
312
313 static int qemu_rbd_create(const char *filename, QemuOpts *opts, Error **errp)
314 {
315 Error *local_err = NULL;
316 int64_t bytes = 0;
317 int64_t objsize;
318 int obj_order = 0;
319 char pool[RBD_MAX_POOL_NAME_SIZE];
320 char name[RBD_MAX_IMAGE_NAME_SIZE];
321 char snap_buf[RBD_MAX_SNAP_NAME_SIZE];
322 char conf[RBD_MAX_CONF_SIZE];
323 char clientname_buf[RBD_MAX_CONF_SIZE];
324 char *clientname;
325 const char *secretid;
326 rados_t cluster;
327 rados_ioctx_t io_ctx;
328 int ret;
329
330 secretid = qemu_opt_get(opts, "password-secret");
331
332 if (qemu_rbd_parsename(filename, pool, sizeof(pool),
333 snap_buf, sizeof(snap_buf),
334 name, sizeof(name),
335 conf, sizeof(conf), &local_err) < 0) {
336 error_propagate(errp, local_err);
337 return -EINVAL;
338 }
339
340 /* Read out options */
341 bytes = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
342 BDRV_SECTOR_SIZE);
343 objsize = qemu_opt_get_size_del(opts, BLOCK_OPT_CLUSTER_SIZE, 0);
344 if (objsize) {
345 if ((objsize - 1) & objsize) { /* not a power of 2? */
346 error_setg(errp, "obj size needs to be power of 2");
347 return -EINVAL;
348 }
349 if (objsize < 4096) {
350 error_setg(errp, "obj size too small");
351 return -EINVAL;
352 }
353 obj_order = ctz32(objsize);
354 }
355
356 clientname = qemu_rbd_parse_clientname(conf, clientname_buf);
357 ret = rados_create(&cluster, clientname);
358 if (ret < 0) {
359 error_setg_errno(errp, -ret, "error initializing");
360 return ret;
361 }
362
363 if (strstr(conf, "conf=") == NULL) {
364 /* try default location, but ignore failure */
365 rados_conf_read_file(cluster, NULL);
366 } else if (conf[0] != '\0' &&
367 qemu_rbd_set_conf(cluster, conf, true, &local_err) < 0) {
368 error_propagate(errp, local_err);
369 ret = -EIO;
370 goto shutdown;
371 }
372
373 if (conf[0] != '\0' &&
374 qemu_rbd_set_conf(cluster, conf, false, &local_err) < 0) {
375 error_propagate(errp, local_err);
376 ret = -EIO;
377 goto shutdown;
378 }
379
380 if (qemu_rbd_set_auth(cluster, secretid, errp) < 0) {
381 ret = -EIO;
382 goto shutdown;
383 }
384
385 ret = rados_connect(cluster);
386 if (ret < 0) {
387 error_setg_errno(errp, -ret, "error connecting");
388 goto shutdown;
389 }
390
391 ret = rados_ioctx_create(cluster, pool, &io_ctx);
392 if (ret < 0) {
393 error_setg_errno(errp, -ret, "error opening pool %s", pool);
394 goto shutdown;
395 }
396
397 ret = rbd_create(io_ctx, name, bytes, &obj_order);
398 if (ret < 0) {
399 error_setg_errno(errp, -ret, "error rbd create");
400 }
401
402 rados_ioctx_destroy(io_ctx);
403
404 shutdown:
405 rados_shutdown(cluster);
406 return ret;
407 }
408
409 /*
410 * This aio completion is being called from rbd_finish_bh() and runs in qemu
411 * BH context.
412 */
413 static void qemu_rbd_complete_aio(RADOSCB *rcb)
414 {
415 RBDAIOCB *acb = rcb->acb;
416 int64_t r;
417
418 r = rcb->ret;
419
420 if (acb->cmd != RBD_AIO_READ) {
421 if (r < 0) {
422 acb->ret = r;
423 acb->error = 1;
424 } else if (!acb->error) {
425 acb->ret = rcb->size;
426 }
427 } else {
428 if (r < 0) {
429 memset(rcb->buf, 0, rcb->size);
430 acb->ret = r;
431 acb->error = 1;
432 } else if (r < rcb->size) {
433 memset(rcb->buf + r, 0, rcb->size - r);
434 if (!acb->error) {
435 acb->ret = rcb->size;
436 }
437 } else if (!acb->error) {
438 acb->ret = r;
439 }
440 }
441
442 g_free(rcb);
443
444 if (acb->cmd == RBD_AIO_READ) {
445 qemu_iovec_from_buf(acb->qiov, 0, acb->bounce, acb->qiov->size);
446 }
447 qemu_vfree(acb->bounce);
448 acb->common.cb(acb->common.opaque, (acb->ret > 0 ? 0 : acb->ret));
449
450 qemu_aio_unref(acb);
451 }
452
453 /* TODO Convert to fine grained options */
454 static QemuOptsList runtime_opts = {
455 .name = "rbd",
456 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
457 .desc = {
458 {
459 .name = "filename",
460 .type = QEMU_OPT_STRING,
461 .help = "Specification of the rbd image",
462 },
463 {
464 .name = "password-secret",
465 .type = QEMU_OPT_STRING,
466 .help = "ID of secret providing the password",
467 },
468 { /* end of list */ }
469 },
470 };
471
472 static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
473 Error **errp)
474 {
475 BDRVRBDState *s = bs->opaque;
476 char pool[RBD_MAX_POOL_NAME_SIZE];
477 char snap_buf[RBD_MAX_SNAP_NAME_SIZE];
478 char conf[RBD_MAX_CONF_SIZE];
479 char clientname_buf[RBD_MAX_CONF_SIZE];
480 char *clientname;
481 const char *secretid;
482 QemuOpts *opts;
483 Error *local_err = NULL;
484 const char *filename;
485 int r;
486
487 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
488 qemu_opts_absorb_qdict(opts, options, &local_err);
489 if (local_err) {
490 error_propagate(errp, local_err);
491 qemu_opts_del(opts);
492 return -EINVAL;
493 }
494
495 filename = qemu_opt_get(opts, "filename");
496 secretid = qemu_opt_get(opts, "password-secret");
497
498 if (qemu_rbd_parsename(filename, pool, sizeof(pool),
499 snap_buf, sizeof(snap_buf),
500 s->name, sizeof(s->name),
501 conf, sizeof(conf), errp) < 0) {
502 r = -EINVAL;
503 goto failed_opts;
504 }
505
506 clientname = qemu_rbd_parse_clientname(conf, clientname_buf);
507 r = rados_create(&s->cluster, clientname);
508 if (r < 0) {
509 error_setg_errno(errp, -r, "error initializing");
510 goto failed_opts;
511 }
512
513 s->snap = NULL;
514 if (snap_buf[0] != '\0') {
515 s->snap = g_strdup(snap_buf);
516 }
517
518 if (strstr(conf, "conf=") == NULL) {
519 /* try default location, but ignore failure */
520 rados_conf_read_file(s->cluster, NULL);
521 } else if (conf[0] != '\0') {
522 r = qemu_rbd_set_conf(s->cluster, conf, true, errp);
523 if (r < 0) {
524 goto failed_shutdown;
525 }
526 }
527
528 if (conf[0] != '\0') {
529 r = qemu_rbd_set_conf(s->cluster, conf, false, errp);
530 if (r < 0) {
531 goto failed_shutdown;
532 }
533 }
534
535 if (qemu_rbd_set_auth(s->cluster, secretid, errp) < 0) {
536 r = -EIO;
537 goto failed_shutdown;
538 }
539
540 /*
541 * Fallback to more conservative semantics if setting cache
542 * options fails. Ignore errors from setting rbd_cache because the
543 * only possible error is that the option does not exist, and
544 * librbd defaults to no caching. If write through caching cannot
545 * be set up, fall back to no caching.
546 */
547 if (flags & BDRV_O_NOCACHE) {
548 rados_conf_set(s->cluster, "rbd_cache", "false");
549 } else {
550 rados_conf_set(s->cluster, "rbd_cache", "true");
551 }
552
553 r = rados_connect(s->cluster);
554 if (r < 0) {
555 error_setg_errno(errp, -r, "error connecting");
556 goto failed_shutdown;
557 }
558
559 r = rados_ioctx_create(s->cluster, pool, &s->io_ctx);
560 if (r < 0) {
561 error_setg_errno(errp, -r, "error opening pool %s", pool);
562 goto failed_shutdown;
563 }
564
565 r = rbd_open(s->io_ctx, s->name, &s->image, s->snap);
566 if (r < 0) {
567 error_setg_errno(errp, -r, "error reading header from %s", s->name);
568 goto failed_open;
569 }
570
571 bs->read_only = (s->snap != NULL);
572
573 qemu_opts_del(opts);
574 return 0;
575
576 failed_open:
577 rados_ioctx_destroy(s->io_ctx);
578 failed_shutdown:
579 rados_shutdown(s->cluster);
580 g_free(s->snap);
581 failed_opts:
582 qemu_opts_del(opts);
583 return r;
584 }
585
586 static void qemu_rbd_close(BlockDriverState *bs)
587 {
588 BDRVRBDState *s = bs->opaque;
589
590 rbd_close(s->image);
591 rados_ioctx_destroy(s->io_ctx);
592 g_free(s->snap);
593 rados_shutdown(s->cluster);
594 }
595
596 static const AIOCBInfo rbd_aiocb_info = {
597 .aiocb_size = sizeof(RBDAIOCB),
598 };
599
600 static void rbd_finish_bh(void *opaque)
601 {
602 RADOSCB *rcb = opaque;
603 qemu_rbd_complete_aio(rcb);
604 }
605
606 /*
607 * This is the callback function for rbd_aio_read and _write
608 *
609 * Note: this function is being called from a non qemu thread so
610 * we need to be careful about what we do here. Generally we only
611 * schedule a BH, and do the rest of the io completion handling
612 * from rbd_finish_bh() which runs in a qemu context.
613 */
614 static void rbd_finish_aiocb(rbd_completion_t c, RADOSCB *rcb)
615 {
616 RBDAIOCB *acb = rcb->acb;
617
618 rcb->ret = rbd_aio_get_return_value(c);
619 rbd_aio_release(c);
620
621 aio_bh_schedule_oneshot(bdrv_get_aio_context(acb->common.bs),
622 rbd_finish_bh, rcb);
623 }
624
625 static int rbd_aio_discard_wrapper(rbd_image_t image,
626 uint64_t off,
627 uint64_t len,
628 rbd_completion_t comp)
629 {
630 #ifdef LIBRBD_SUPPORTS_DISCARD
631 return rbd_aio_discard(image, off, len, comp);
632 #else
633 return -ENOTSUP;
634 #endif
635 }
636
637 static int rbd_aio_flush_wrapper(rbd_image_t image,
638 rbd_completion_t comp)
639 {
640 #ifdef LIBRBD_SUPPORTS_AIO_FLUSH
641 return rbd_aio_flush(image, comp);
642 #else
643 return -ENOTSUP;
644 #endif
645 }
646
647 static BlockAIOCB *rbd_start_aio(BlockDriverState *bs,
648 int64_t off,
649 QEMUIOVector *qiov,
650 int64_t size,
651 BlockCompletionFunc *cb,
652 void *opaque,
653 RBDAIOCmd cmd)
654 {
655 RBDAIOCB *acb;
656 RADOSCB *rcb = NULL;
657 rbd_completion_t c;
658 char *buf;
659 int r;
660
661 BDRVRBDState *s = bs->opaque;
662
663 acb = qemu_aio_get(&rbd_aiocb_info, bs, cb, opaque);
664 acb->cmd = cmd;
665 acb->qiov = qiov;
666 assert(!qiov || qiov->size == size);
667 if (cmd == RBD_AIO_DISCARD || cmd == RBD_AIO_FLUSH) {
668 acb->bounce = NULL;
669 } else {
670 acb->bounce = qemu_try_blockalign(bs, qiov->size);
671 if (acb->bounce == NULL) {
672 goto failed;
673 }
674 }
675 acb->ret = 0;
676 acb->error = 0;
677 acb->s = s;
678
679 if (cmd == RBD_AIO_WRITE) {
680 qemu_iovec_to_buf(acb->qiov, 0, acb->bounce, qiov->size);
681 }
682
683 buf = acb->bounce;
684
685 rcb = g_new(RADOSCB, 1);
686 rcb->acb = acb;
687 rcb->buf = buf;
688 rcb->s = acb->s;
689 rcb->size = size;
690 r = rbd_aio_create_completion(rcb, (rbd_callback_t) rbd_finish_aiocb, &c);
691 if (r < 0) {
692 goto failed;
693 }
694
695 switch (cmd) {
696 case RBD_AIO_WRITE:
697 r = rbd_aio_write(s->image, off, size, buf, c);
698 break;
699 case RBD_AIO_READ:
700 r = rbd_aio_read(s->image, off, size, buf, c);
701 break;
702 case RBD_AIO_DISCARD:
703 r = rbd_aio_discard_wrapper(s->image, off, size, c);
704 break;
705 case RBD_AIO_FLUSH:
706 r = rbd_aio_flush_wrapper(s->image, c);
707 break;
708 default:
709 r = -EINVAL;
710 }
711
712 if (r < 0) {
713 goto failed_completion;
714 }
715
716 return &acb->common;
717
718 failed_completion:
719 rbd_aio_release(c);
720 failed:
721 g_free(rcb);
722 qemu_vfree(acb->bounce);
723 qemu_aio_unref(acb);
724 return NULL;
725 }
726
727 static BlockAIOCB *qemu_rbd_aio_readv(BlockDriverState *bs,
728 int64_t sector_num,
729 QEMUIOVector *qiov,
730 int nb_sectors,
731 BlockCompletionFunc *cb,
732 void *opaque)
733 {
734 return rbd_start_aio(bs, sector_num << BDRV_SECTOR_BITS, qiov,
735 (int64_t) nb_sectors << BDRV_SECTOR_BITS, cb, opaque,
736 RBD_AIO_READ);
737 }
738
739 static BlockAIOCB *qemu_rbd_aio_writev(BlockDriverState *bs,
740 int64_t sector_num,
741 QEMUIOVector *qiov,
742 int nb_sectors,
743 BlockCompletionFunc *cb,
744 void *opaque)
745 {
746 return rbd_start_aio(bs, sector_num << BDRV_SECTOR_BITS, qiov,
747 (int64_t) nb_sectors << BDRV_SECTOR_BITS, cb, opaque,
748 RBD_AIO_WRITE);
749 }
750
751 #ifdef LIBRBD_SUPPORTS_AIO_FLUSH
752 static BlockAIOCB *qemu_rbd_aio_flush(BlockDriverState *bs,
753 BlockCompletionFunc *cb,
754 void *opaque)
755 {
756 return rbd_start_aio(bs, 0, NULL, 0, cb, opaque, RBD_AIO_FLUSH);
757 }
758
759 #else
760
761 static int qemu_rbd_co_flush(BlockDriverState *bs)
762 {
763 #if LIBRBD_VERSION_CODE >= LIBRBD_VERSION(0, 1, 1)
764 /* rbd_flush added in 0.1.1 */
765 BDRVRBDState *s = bs->opaque;
766 return rbd_flush(s->image);
767 #else
768 return 0;
769 #endif
770 }
771 #endif
772
773 static int qemu_rbd_getinfo(BlockDriverState *bs, BlockDriverInfo *bdi)
774 {
775 BDRVRBDState *s = bs->opaque;
776 rbd_image_info_t info;
777 int r;
778
779 r = rbd_stat(s->image, &info, sizeof(info));
780 if (r < 0) {
781 return r;
782 }
783
784 bdi->cluster_size = info.obj_size;
785 return 0;
786 }
787
788 static int64_t qemu_rbd_getlength(BlockDriverState *bs)
789 {
790 BDRVRBDState *s = bs->opaque;
791 rbd_image_info_t info;
792 int r;
793
794 r = rbd_stat(s->image, &info, sizeof(info));
795 if (r < 0) {
796 return r;
797 }
798
799 return info.size;
800 }
801
802 static int qemu_rbd_truncate(BlockDriverState *bs, int64_t offset)
803 {
804 BDRVRBDState *s = bs->opaque;
805 int r;
806
807 r = rbd_resize(s->image, offset);
808 if (r < 0) {
809 return r;
810 }
811
812 return 0;
813 }
814
815 static int qemu_rbd_snap_create(BlockDriverState *bs,
816 QEMUSnapshotInfo *sn_info)
817 {
818 BDRVRBDState *s = bs->opaque;
819 int r;
820
821 if (sn_info->name[0] == '\0') {
822 return -EINVAL; /* we need a name for rbd snapshots */
823 }
824
825 /*
826 * rbd snapshots are using the name as the user controlled unique identifier
827 * we can't use the rbd snapid for that purpose, as it can't be set
828 */
829 if (sn_info->id_str[0] != '\0' &&
830 strcmp(sn_info->id_str, sn_info->name) != 0) {
831 return -EINVAL;
832 }
833
834 if (strlen(sn_info->name) >= sizeof(sn_info->id_str)) {
835 return -ERANGE;
836 }
837
838 r = rbd_snap_create(s->image, sn_info->name);
839 if (r < 0) {
840 error_report("failed to create snap: %s", strerror(-r));
841 return r;
842 }
843
844 return 0;
845 }
846
847 static int qemu_rbd_snap_remove(BlockDriverState *bs,
848 const char *snapshot_id,
849 const char *snapshot_name,
850 Error **errp)
851 {
852 BDRVRBDState *s = bs->opaque;
853 int r;
854
855 if (!snapshot_name) {
856 error_setg(errp, "rbd need a valid snapshot name");
857 return -EINVAL;
858 }
859
860 /* If snapshot_id is specified, it must be equal to name, see
861 qemu_rbd_snap_list() */
862 if (snapshot_id && strcmp(snapshot_id, snapshot_name)) {
863 error_setg(errp,
864 "rbd do not support snapshot id, it should be NULL or "
865 "equal to snapshot name");
866 return -EINVAL;
867 }
868
869 r = rbd_snap_remove(s->image, snapshot_name);
870 if (r < 0) {
871 error_setg_errno(errp, -r, "Failed to remove the snapshot");
872 }
873 return r;
874 }
875
876 static int qemu_rbd_snap_rollback(BlockDriverState *bs,
877 const char *snapshot_name)
878 {
879 BDRVRBDState *s = bs->opaque;
880
881 return rbd_snap_rollback(s->image, snapshot_name);
882 }
883
884 static int qemu_rbd_snap_list(BlockDriverState *bs,
885 QEMUSnapshotInfo **psn_tab)
886 {
887 BDRVRBDState *s = bs->opaque;
888 QEMUSnapshotInfo *sn_info, *sn_tab = NULL;
889 int i, snap_count;
890 rbd_snap_info_t *snaps;
891 int max_snaps = RBD_MAX_SNAPS;
892
893 do {
894 snaps = g_new(rbd_snap_info_t, max_snaps);
895 snap_count = rbd_snap_list(s->image, snaps, &max_snaps);
896 if (snap_count <= 0) {
897 g_free(snaps);
898 }
899 } while (snap_count == -ERANGE);
900
901 if (snap_count <= 0) {
902 goto done;
903 }
904
905 sn_tab = g_new0(QEMUSnapshotInfo, snap_count);
906
907 for (i = 0; i < snap_count; i++) {
908 const char *snap_name = snaps[i].name;
909
910 sn_info = sn_tab + i;
911 pstrcpy(sn_info->id_str, sizeof(sn_info->id_str), snap_name);
912 pstrcpy(sn_info->name, sizeof(sn_info->name), snap_name);
913
914 sn_info->vm_state_size = snaps[i].size;
915 sn_info->date_sec = 0;
916 sn_info->date_nsec = 0;
917 sn_info->vm_clock_nsec = 0;
918 }
919 rbd_snap_list_end(snaps);
920 g_free(snaps);
921
922 done:
923 *psn_tab = sn_tab;
924 return snap_count;
925 }
926
927 #ifdef LIBRBD_SUPPORTS_DISCARD
928 static BlockAIOCB *qemu_rbd_aio_pdiscard(BlockDriverState *bs,
929 int64_t offset,
930 int count,
931 BlockCompletionFunc *cb,
932 void *opaque)
933 {
934 return rbd_start_aio(bs, offset, NULL, count, cb, opaque,
935 RBD_AIO_DISCARD);
936 }
937 #endif
938
939 #ifdef LIBRBD_SUPPORTS_INVALIDATE
940 static void qemu_rbd_invalidate_cache(BlockDriverState *bs,
941 Error **errp)
942 {
943 BDRVRBDState *s = bs->opaque;
944 int r = rbd_invalidate_cache(s->image);
945 if (r < 0) {
946 error_setg_errno(errp, -r, "Failed to invalidate the cache");
947 }
948 }
949 #endif
950
951 static QemuOptsList qemu_rbd_create_opts = {
952 .name = "rbd-create-opts",
953 .head = QTAILQ_HEAD_INITIALIZER(qemu_rbd_create_opts.head),
954 .desc = {
955 {
956 .name = BLOCK_OPT_SIZE,
957 .type = QEMU_OPT_SIZE,
958 .help = "Virtual disk size"
959 },
960 {
961 .name = BLOCK_OPT_CLUSTER_SIZE,
962 .type = QEMU_OPT_SIZE,
963 .help = "RBD object size"
964 },
965 {
966 .name = "password-secret",
967 .type = QEMU_OPT_STRING,
968 .help = "ID of secret providing the password",
969 },
970 { /* end of list */ }
971 }
972 };
973
974 static BlockDriver bdrv_rbd = {
975 .format_name = "rbd",
976 .instance_size = sizeof(BDRVRBDState),
977 .bdrv_needs_filename = true,
978 .bdrv_file_open = qemu_rbd_open,
979 .bdrv_close = qemu_rbd_close,
980 .bdrv_create = qemu_rbd_create,
981 .bdrv_has_zero_init = bdrv_has_zero_init_1,
982 .bdrv_get_info = qemu_rbd_getinfo,
983 .create_opts = &qemu_rbd_create_opts,
984 .bdrv_getlength = qemu_rbd_getlength,
985 .bdrv_truncate = qemu_rbd_truncate,
986 .protocol_name = "rbd",
987
988 .bdrv_aio_readv = qemu_rbd_aio_readv,
989 .bdrv_aio_writev = qemu_rbd_aio_writev,
990
991 #ifdef LIBRBD_SUPPORTS_AIO_FLUSH
992 .bdrv_aio_flush = qemu_rbd_aio_flush,
993 #else
994 .bdrv_co_flush_to_disk = qemu_rbd_co_flush,
995 #endif
996
997 #ifdef LIBRBD_SUPPORTS_DISCARD
998 .bdrv_aio_pdiscard = qemu_rbd_aio_pdiscard,
999 #endif
1000
1001 .bdrv_snapshot_create = qemu_rbd_snap_create,
1002 .bdrv_snapshot_delete = qemu_rbd_snap_remove,
1003 .bdrv_snapshot_list = qemu_rbd_snap_list,
1004 .bdrv_snapshot_goto = qemu_rbd_snap_rollback,
1005 #ifdef LIBRBD_SUPPORTS_INVALIDATE
1006 .bdrv_invalidate_cache = qemu_rbd_invalidate_cache,
1007 #endif
1008 };
1009
1010 static void bdrv_rbd_init(void)
1011 {
1012 bdrv_register(&bdrv_rbd);
1013 }
1014
1015 block_init(bdrv_rbd_init);