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1/*
2 rbd.c -- Export ceph rados objects as a Linux block device
3
4
5 based on drivers/block/osdblk.c:
6
7 Copyright 2009 Red Hat, Inc.
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; see the file COPYING. If not, write to
20 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
21
22
23
24 For usage instructions, please refer to:
25
26 Documentation/ABI/testing/sysfs-bus-rbd
27
28 */
29
30#include <linux/ceph/libceph.h>
31#include <linux/ceph/osd_client.h>
32#include <linux/ceph/mon_client.h>
33#include <linux/ceph/decode.h>
34#include <linux/parser.h>
35
36#include <linux/kernel.h>
37#include <linux/device.h>
38#include <linux/module.h>
39#include <linux/fs.h>
40#include <linux/blkdev.h>
41
42#include "rbd_types.h"
43
44#define DRV_NAME "rbd"
45#define DRV_NAME_LONG "rbd (rados block device)"
46
47#define RBD_MINORS_PER_MAJOR 256 /* max minors per blkdev */
48
49#define RBD_MAX_MD_NAME_LEN (96 + sizeof(RBD_SUFFIX))
50#define RBD_MAX_POOL_NAME_LEN 64
51#define RBD_MAX_SNAP_NAME_LEN 32
52#define RBD_MAX_OPT_LEN 1024
53
54#define RBD_SNAP_HEAD_NAME "-"
55
56#define DEV_NAME_LEN 32
57
58#define RBD_NOTIFY_TIMEOUT_DEFAULT 10
59
60/*
61 * block device image metadata (in-memory version)
62 */
63struct rbd_image_header {
64 u64 image_size;
65 char block_name[32];
66 __u8 obj_order;
67 __u8 crypt_type;
68 __u8 comp_type;
69 struct rw_semaphore snap_rwsem;
70 struct ceph_snap_context *snapc;
71 size_t snap_names_len;
72 u64 snap_seq;
73 u32 total_snaps;
74
75 char *snap_names;
76 u64 *snap_sizes;
77
78 u64 obj_version;
79};
80
81struct rbd_options {
82 int notify_timeout;
83};
84
85/*
86 * an instance of the client. multiple devices may share a client.
87 */
88struct rbd_client {
89 struct ceph_client *client;
90 struct rbd_options *rbd_opts;
91 struct kref kref;
92 struct list_head node;
93};
94
95struct rbd_req_coll;
96
97/*
98 * a single io request
99 */
100struct rbd_request {
101 struct request *rq; /* blk layer request */
102 struct bio *bio; /* cloned bio */
103 struct page **pages; /* list of used pages */
104 u64 len;
105 int coll_index;
106 struct rbd_req_coll *coll;
107};
108
109struct rbd_req_status {
110 int done;
111 int rc;
112 u64 bytes;
113};
114
115/*
116 * a collection of requests
117 */
118struct rbd_req_coll {
119 int total;
120 int num_done;
121 struct kref kref;
122 struct rbd_req_status status[0];
123};
124
125struct rbd_snap {
126 struct device dev;
127 const char *name;
128 size_t size;
129 struct list_head node;
130 u64 id;
131};
132
133/*
134 * a single device
135 */
136struct rbd_device {
137 int id; /* blkdev unique id */
138
139 int major; /* blkdev assigned major */
140 struct gendisk *disk; /* blkdev's gendisk and rq */
141 struct request_queue *q;
142
143 struct ceph_client *client;
144 struct rbd_client *rbd_client;
145
146 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */
147
148 spinlock_t lock; /* queue lock */
149
150 struct rbd_image_header header;
151 char obj[RBD_MAX_OBJ_NAME_LEN]; /* rbd image name */
152 int obj_len;
153 char obj_md_name[RBD_MAX_MD_NAME_LEN]; /* hdr nm. */
154 char pool_name[RBD_MAX_POOL_NAME_LEN];
155 int poolid;
156
157 struct ceph_osd_event *watch_event;
158 struct ceph_osd_request *watch_request;
159
160 char snap_name[RBD_MAX_SNAP_NAME_LEN];
161 u32 cur_snap; /* index+1 of current snapshot within snap context
162 0 - for the head */
163 int read_only;
164
165 struct list_head node;
166
167 /* list of snapshots */
168 struct list_head snaps;
169
170 /* sysfs related */
171 struct device dev;
172};
173
174static struct bus_type rbd_bus_type = {
175 .name = "rbd",
176};
177
178static spinlock_t node_lock; /* protects client get/put */
179
180static DEFINE_MUTEX(ctl_mutex); /* Serialize open/close/setup/teardown */
181static LIST_HEAD(rbd_dev_list); /* devices */
182static LIST_HEAD(rbd_client_list); /* clients */
183
184static int __rbd_init_snaps_header(struct rbd_device *rbd_dev);
185static void rbd_dev_release(struct device *dev);
186static ssize_t rbd_snap_rollback(struct device *dev,
187 struct device_attribute *attr,
188 const char *buf,
189 size_t size);
190static ssize_t rbd_snap_add(struct device *dev,
191 struct device_attribute *attr,
192 const char *buf,
193 size_t count);
194static void __rbd_remove_snap_dev(struct rbd_device *rbd_dev,
195 struct rbd_snap *snap);;
196
197
198static struct rbd_device *dev_to_rbd(struct device *dev)
199{
200 return container_of(dev, struct rbd_device, dev);
201}
202
203static struct device *rbd_get_dev(struct rbd_device *rbd_dev)
204{
205 return get_device(&rbd_dev->dev);
206}
207
208static void rbd_put_dev(struct rbd_device *rbd_dev)
209{
210 put_device(&rbd_dev->dev);
211}
212
213static int __rbd_update_snaps(struct rbd_device *rbd_dev);
214
215static int rbd_open(struct block_device *bdev, fmode_t mode)
216{
217 struct gendisk *disk = bdev->bd_disk;
218 struct rbd_device *rbd_dev = disk->private_data;
219
220 rbd_get_dev(rbd_dev);
221
222 set_device_ro(bdev, rbd_dev->read_only);
223
224 if ((mode & FMODE_WRITE) && rbd_dev->read_only)
225 return -EROFS;
226
227 return 0;
228}
229
230static int rbd_release(struct gendisk *disk, fmode_t mode)
231{
232 struct rbd_device *rbd_dev = disk->private_data;
233
234 rbd_put_dev(rbd_dev);
235
236 return 0;
237}
238
239static const struct block_device_operations rbd_bd_ops = {
240 .owner = THIS_MODULE,
241 .open = rbd_open,
242 .release = rbd_release,
243};
244
245/*
246 * Initialize an rbd client instance.
247 * We own *opt.
248 */
249static struct rbd_client *rbd_client_create(struct ceph_options *opt,
250 struct rbd_options *rbd_opts)
251{
252 struct rbd_client *rbdc;
253 int ret = -ENOMEM;
254
255 dout("rbd_client_create\n");
256 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
257 if (!rbdc)
258 goto out_opt;
259
260 kref_init(&rbdc->kref);
261 INIT_LIST_HEAD(&rbdc->node);
262
263 rbdc->client = ceph_create_client(opt, rbdc);
264 if (IS_ERR(rbdc->client))
265 goto out_rbdc;
266 opt = NULL; /* Now rbdc->client is responsible for opt */
267
268 ret = ceph_open_session(rbdc->client);
269 if (ret < 0)
270 goto out_err;
271
272 rbdc->rbd_opts = rbd_opts;
273
274 spin_lock(&node_lock);
275 list_add_tail(&rbdc->node, &rbd_client_list);
276 spin_unlock(&node_lock);
277
278 dout("rbd_client_create created %p\n", rbdc);
279 return rbdc;
280
281out_err:
282 ceph_destroy_client(rbdc->client);
283out_rbdc:
284 kfree(rbdc);
285out_opt:
286 if (opt)
287 ceph_destroy_options(opt);
288 return ERR_PTR(ret);
289}
290
291/*
292 * Find a ceph client with specific addr and configuration.
293 */
294static struct rbd_client *__rbd_client_find(struct ceph_options *opt)
295{
296 struct rbd_client *client_node;
297
298 if (opt->flags & CEPH_OPT_NOSHARE)
299 return NULL;
300
301 list_for_each_entry(client_node, &rbd_client_list, node)
302 if (ceph_compare_options(opt, client_node->client) == 0)
303 return client_node;
304 return NULL;
305}
306
307/*
308 * mount options
309 */
310enum {
311 Opt_notify_timeout,
312 Opt_last_int,
313 /* int args above */
314 Opt_last_string,
315 /* string args above */
316};
317
318static match_table_t rbdopt_tokens = {
319 {Opt_notify_timeout, "notify_timeout=%d"},
320 /* int args above */
321 /* string args above */
322 {-1, NULL}
323};
324
325static int parse_rbd_opts_token(char *c, void *private)
326{
327 struct rbd_options *rbdopt = private;
328 substring_t argstr[MAX_OPT_ARGS];
329 int token, intval, ret;
330
331 token = match_token((char *)c, rbdopt_tokens, argstr);
332 if (token < 0)
333 return -EINVAL;
334
335 if (token < Opt_last_int) {
336 ret = match_int(&argstr[0], &intval);
337 if (ret < 0) {
338 pr_err("bad mount option arg (not int) "
339 "at '%s'\n", c);
340 return ret;
341 }
342 dout("got int token %d val %d\n", token, intval);
343 } else if (token > Opt_last_int && token < Opt_last_string) {
344 dout("got string token %d val %s\n", token,
345 argstr[0].from);
346 } else {
347 dout("got token %d\n", token);
348 }
349
350 switch (token) {
351 case Opt_notify_timeout:
352 rbdopt->notify_timeout = intval;
353 break;
354 default:
355 BUG_ON(token);
356 }
357 return 0;
358}
359
360/*
361 * Get a ceph client with specific addr and configuration, if one does
362 * not exist create it.
363 */
364static int rbd_get_client(struct rbd_device *rbd_dev, const char *mon_addr,
365 char *options)
366{
367 struct rbd_client *rbdc;
368 struct ceph_options *opt;
369 int ret;
370 struct rbd_options *rbd_opts;
371
372 rbd_opts = kzalloc(sizeof(*rbd_opts), GFP_KERNEL);
373 if (!rbd_opts)
374 return -ENOMEM;
375
376 rbd_opts->notify_timeout = RBD_NOTIFY_TIMEOUT_DEFAULT;
377
378 ret = ceph_parse_options(&opt, options, mon_addr,
379 mon_addr + strlen(mon_addr), parse_rbd_opts_token, rbd_opts);
380 if (ret < 0)
381 goto done_err;
382
383 spin_lock(&node_lock);
384 rbdc = __rbd_client_find(opt);
385 if (rbdc) {
386 ceph_destroy_options(opt);
387
388 /* using an existing client */
389 kref_get(&rbdc->kref);
390 rbd_dev->rbd_client = rbdc;
391 rbd_dev->client = rbdc->client;
392 spin_unlock(&node_lock);
393 return 0;
394 }
395 spin_unlock(&node_lock);
396
397 rbdc = rbd_client_create(opt, rbd_opts);
398 if (IS_ERR(rbdc)) {
399 ret = PTR_ERR(rbdc);
400 goto done_err;
401 }
402
403 rbd_dev->rbd_client = rbdc;
404 rbd_dev->client = rbdc->client;
405 return 0;
406done_err:
407 kfree(rbd_opts);
408 return ret;
409}
410
411/*
412 * Destroy ceph client
413 */
414static void rbd_client_release(struct kref *kref)
415{
416 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
417
418 dout("rbd_release_client %p\n", rbdc);
419 spin_lock(&node_lock);
420 list_del(&rbdc->node);
421 spin_unlock(&node_lock);
422
423 ceph_destroy_client(rbdc->client);
424 kfree(rbdc->rbd_opts);
425 kfree(rbdc);
426}
427
428/*
429 * Drop reference to ceph client node. If it's not referenced anymore, release
430 * it.
431 */
432static void rbd_put_client(struct rbd_device *rbd_dev)
433{
434 kref_put(&rbd_dev->rbd_client->kref, rbd_client_release);
435 rbd_dev->rbd_client = NULL;
436 rbd_dev->client = NULL;
437}
438
439/*
440 * Destroy requests collection
441 */
442static void rbd_coll_release(struct kref *kref)
443{
444 struct rbd_req_coll *coll =
445 container_of(kref, struct rbd_req_coll, kref);
446
447 dout("rbd_coll_release %p\n", coll);
448 kfree(coll);
449}
450
451/*
452 * Create a new header structure, translate header format from the on-disk
453 * header.
454 */
455static int rbd_header_from_disk(struct rbd_image_header *header,
456 struct rbd_image_header_ondisk *ondisk,
457 int allocated_snaps,
458 gfp_t gfp_flags)
459{
460 int i;
461 u32 snap_count = le32_to_cpu(ondisk->snap_count);
462 int ret = -ENOMEM;
463
464 init_rwsem(&header->snap_rwsem);
465 header->snap_names_len = le64_to_cpu(ondisk->snap_names_len);
466 header->snapc = kmalloc(sizeof(struct ceph_snap_context) +
467 snap_count *
468 sizeof(struct rbd_image_snap_ondisk),
469 gfp_flags);
470 if (!header->snapc)
471 return -ENOMEM;
472 if (snap_count) {
473 header->snap_names = kmalloc(header->snap_names_len,
474 GFP_KERNEL);
475 if (!header->snap_names)
476 goto err_snapc;
477 header->snap_sizes = kmalloc(snap_count * sizeof(u64),
478 GFP_KERNEL);
479 if (!header->snap_sizes)
480 goto err_names;
481 } else {
482 header->snap_names = NULL;
483 header->snap_sizes = NULL;
484 }
485 memcpy(header->block_name, ondisk->block_name,
486 sizeof(ondisk->block_name));
487
488 header->image_size = le64_to_cpu(ondisk->image_size);
489 header->obj_order = ondisk->options.order;
490 header->crypt_type = ondisk->options.crypt_type;
491 header->comp_type = ondisk->options.comp_type;
492
493 atomic_set(&header->snapc->nref, 1);
494 header->snap_seq = le64_to_cpu(ondisk->snap_seq);
495 header->snapc->num_snaps = snap_count;
496 header->total_snaps = snap_count;
497
498 if (snap_count &&
499 allocated_snaps == snap_count) {
500 for (i = 0; i < snap_count; i++) {
501 header->snapc->snaps[i] =
502 le64_to_cpu(ondisk->snaps[i].id);
503 header->snap_sizes[i] =
504 le64_to_cpu(ondisk->snaps[i].image_size);
505 }
506
507 /* copy snapshot names */
508 memcpy(header->snap_names, &ondisk->snaps[i],
509 header->snap_names_len);
510 }
511
512 return 0;
513
514err_names:
515 kfree(header->snap_names);
516err_snapc:
517 kfree(header->snapc);
518 return ret;
519}
520
521static int snap_index(struct rbd_image_header *header, int snap_num)
522{
523 return header->total_snaps - snap_num;
524}
525
526static u64 cur_snap_id(struct rbd_device *rbd_dev)
527{
528 struct rbd_image_header *header = &rbd_dev->header;
529
530 if (!rbd_dev->cur_snap)
531 return 0;
532
533 return header->snapc->snaps[snap_index(header, rbd_dev->cur_snap)];
534}
535
536static int snap_by_name(struct rbd_image_header *header, const char *snap_name,
537 u64 *seq, u64 *size)
538{
539 int i;
540 char *p = header->snap_names;
541
542 for (i = 0; i < header->total_snaps; i++, p += strlen(p) + 1) {
543 if (strcmp(snap_name, p) == 0)
544 break;
545 }
546 if (i == header->total_snaps)
547 return -ENOENT;
548 if (seq)
549 *seq = header->snapc->snaps[i];
550
551 if (size)
552 *size = header->snap_sizes[i];
553
554 return i;
555}
556
557static int rbd_header_set_snap(struct rbd_device *dev,
558 const char *snap_name,
559 u64 *size)
560{
561 struct rbd_image_header *header = &dev->header;
562 struct ceph_snap_context *snapc = header->snapc;
563 int ret = -ENOENT;
564
565 down_write(&header->snap_rwsem);
566
567 if (!snap_name ||
568 !*snap_name ||
569 strcmp(snap_name, "-") == 0 ||
570 strcmp(snap_name, RBD_SNAP_HEAD_NAME) == 0) {
571 if (header->total_snaps)
572 snapc->seq = header->snap_seq;
573 else
574 snapc->seq = 0;
575 dev->cur_snap = 0;
576 dev->read_only = 0;
577 if (size)
578 *size = header->image_size;
579 } else {
580 ret = snap_by_name(header, snap_name, &snapc->seq, size);
581 if (ret < 0)
582 goto done;
583
584 dev->cur_snap = header->total_snaps - ret;
585 dev->read_only = 1;
586 }
587
588 ret = 0;
589done:
590 up_write(&header->snap_rwsem);
591 return ret;
592}
593
594static void rbd_header_free(struct rbd_image_header *header)
595{
596 kfree(header->snapc);
597 kfree(header->snap_names);
598 kfree(header->snap_sizes);
599}
600
601/*
602 * get the actual striped segment name, offset and length
603 */
604static u64 rbd_get_segment(struct rbd_image_header *header,
605 const char *block_name,
606 u64 ofs, u64 len,
607 char *seg_name, u64 *segofs)
608{
609 u64 seg = ofs >> header->obj_order;
610
611 if (seg_name)
612 snprintf(seg_name, RBD_MAX_SEG_NAME_LEN,
613 "%s.%012llx", block_name, seg);
614
615 ofs = ofs & ((1 << header->obj_order) - 1);
616 len = min_t(u64, len, (1 << header->obj_order) - ofs);
617
618 if (segofs)
619 *segofs = ofs;
620
621 return len;
622}
623
624static int rbd_get_num_segments(struct rbd_image_header *header,
625 u64 ofs, u64 len)
626{
627 u64 start_seg = ofs >> header->obj_order;
628 u64 end_seg = (ofs + len - 1) >> header->obj_order;
629 return end_seg - start_seg + 1;
630}
631
632/*
633 * returns the size of an object in the image
634 */
635static u64 rbd_obj_bytes(struct rbd_image_header *header)
636{
637 return 1 << header->obj_order;
638}
639
640/*
641 * bio helpers
642 */
643
644static void bio_chain_put(struct bio *chain)
645{
646 struct bio *tmp;
647
648 while (chain) {
649 tmp = chain;
650 chain = chain->bi_next;
651 bio_put(tmp);
652 }
653}
654
655/*
656 * zeros a bio chain, starting at specific offset
657 */
658static void zero_bio_chain(struct bio *chain, int start_ofs)
659{
660 struct bio_vec *bv;
661 unsigned long flags;
662 void *buf;
663 int i;
664 int pos = 0;
665
666 while (chain) {
667 bio_for_each_segment(bv, chain, i) {
668 if (pos + bv->bv_len > start_ofs) {
669 int remainder = max(start_ofs - pos, 0);
670 buf = bvec_kmap_irq(bv, &flags);
671 memset(buf + remainder, 0,
672 bv->bv_len - remainder);
673 bvec_kunmap_irq(buf, &flags);
674 }
675 pos += bv->bv_len;
676 }
677
678 chain = chain->bi_next;
679 }
680}
681
682/*
683 * bio_chain_clone - clone a chain of bios up to a certain length.
684 * might return a bio_pair that will need to be released.
685 */
686static struct bio *bio_chain_clone(struct bio **old, struct bio **next,
687 struct bio_pair **bp,
688 int len, gfp_t gfpmask)
689{
690 struct bio *tmp, *old_chain = *old, *new_chain = NULL, *tail = NULL;
691 int total = 0;
692
693 if (*bp) {
694 bio_pair_release(*bp);
695 *bp = NULL;
696 }
697
698 while (old_chain && (total < len)) {
699 tmp = bio_kmalloc(gfpmask, old_chain->bi_max_vecs);
700 if (!tmp)
701 goto err_out;
702
703 if (total + old_chain->bi_size > len) {
704 struct bio_pair *bp;
705
706 /*
707 * this split can only happen with a single paged bio,
708 * split_bio will BUG_ON if this is not the case
709 */
710 dout("bio_chain_clone split! total=%d remaining=%d"
711 "bi_size=%d\n",
712 (int)total, (int)len-total,
713 (int)old_chain->bi_size);
714
715 /* split the bio. We'll release it either in the next
716 call, or it will have to be released outside */
717 bp = bio_split(old_chain, (len - total) / 512ULL);
718 if (!bp)
719 goto err_out;
720
721 __bio_clone(tmp, &bp->bio1);
722
723 *next = &bp->bio2;
724 } else {
725 __bio_clone(tmp, old_chain);
726 *next = old_chain->bi_next;
727 }
728
729 tmp->bi_bdev = NULL;
730 gfpmask &= ~__GFP_WAIT;
731 tmp->bi_next = NULL;
732
733 if (!new_chain) {
734 new_chain = tail = tmp;
735 } else {
736 tail->bi_next = tmp;
737 tail = tmp;
738 }
739 old_chain = old_chain->bi_next;
740
741 total += tmp->bi_size;
742 }
743
744 BUG_ON(total < len);
745
746 if (tail)
747 tail->bi_next = NULL;
748
749 *old = old_chain;
750
751 return new_chain;
752
753err_out:
754 dout("bio_chain_clone with err\n");
755 bio_chain_put(new_chain);
756 return NULL;
757}
758
759/*
760 * helpers for osd request op vectors.
761 */
762static int rbd_create_rw_ops(struct ceph_osd_req_op **ops,
763 int num_ops,
764 int opcode,
765 u32 payload_len)
766{
767 *ops = kzalloc(sizeof(struct ceph_osd_req_op) * (num_ops + 1),
768 GFP_NOIO);
769 if (!*ops)
770 return -ENOMEM;
771 (*ops)[0].op = opcode;
772 /*
773 * op extent offset and length will be set later on
774 * in calc_raw_layout()
775 */
776 (*ops)[0].payload_len = payload_len;
777 return 0;
778}
779
780static void rbd_destroy_ops(struct ceph_osd_req_op *ops)
781{
782 kfree(ops);
783}
784
785static void rbd_coll_end_req_index(struct request *rq,
786 struct rbd_req_coll *coll,
787 int index,
788 int ret, u64 len)
789{
790 struct request_queue *q;
791 int min, max, i;
792
793 dout("rbd_coll_end_req_index %p index %d ret %d len %lld\n",
794 coll, index, ret, len);
795
796 if (!rq)
797 return;
798
799 if (!coll) {
800 blk_end_request(rq, ret, len);
801 return;
802 }
803
804 q = rq->q;
805
806 spin_lock_irq(q->queue_lock);
807 coll->status[index].done = 1;
808 coll->status[index].rc = ret;
809 coll->status[index].bytes = len;
810 max = min = coll->num_done;
811 while (max < coll->total && coll->status[max].done)
812 max++;
813
814 for (i = min; i<max; i++) {
815 __blk_end_request(rq, coll->status[i].rc,
816 coll->status[i].bytes);
817 coll->num_done++;
818 kref_put(&coll->kref, rbd_coll_release);
819 }
820 spin_unlock_irq(q->queue_lock);
821}
822
823static void rbd_coll_end_req(struct rbd_request *req,
824 int ret, u64 len)
825{
826 rbd_coll_end_req_index(req->rq, req->coll, req->coll_index, ret, len);
827}
828
829/*
830 * Send ceph osd request
831 */
832static int rbd_do_request(struct request *rq,
833 struct rbd_device *dev,
834 struct ceph_snap_context *snapc,
835 u64 snapid,
836 const char *obj, u64 ofs, u64 len,
837 struct bio *bio,
838 struct page **pages,
839 int num_pages,
840 int flags,
841 struct ceph_osd_req_op *ops,
842 int num_reply,
843 struct rbd_req_coll *coll,
844 int coll_index,
845 void (*rbd_cb)(struct ceph_osd_request *req,
846 struct ceph_msg *msg),
847 struct ceph_osd_request **linger_req,
848 u64 *ver)
849{
850 struct ceph_osd_request *req;
851 struct ceph_file_layout *layout;
852 int ret;
853 u64 bno;
854 struct timespec mtime = CURRENT_TIME;
855 struct rbd_request *req_data;
856 struct ceph_osd_request_head *reqhead;
857 struct rbd_image_header *header = &dev->header;
858
859 req_data = kzalloc(sizeof(*req_data), GFP_NOIO);
860 if (!req_data) {
861 if (coll)
862 rbd_coll_end_req_index(rq, coll, coll_index,
863 -ENOMEM, len);
864 return -ENOMEM;
865 }
866
867 if (coll) {
868 req_data->coll = coll;
869 req_data->coll_index = coll_index;
870 }
871
872 dout("rbd_do_request obj=%s ofs=%lld len=%lld\n", obj, len, ofs);
873
874 down_read(&header->snap_rwsem);
875
876 req = ceph_osdc_alloc_request(&dev->client->osdc, flags,
877 snapc,
878 ops,
879 false,
880 GFP_NOIO, pages, bio);
881 if (!req) {
882 up_read(&header->snap_rwsem);
883 ret = -ENOMEM;
884 goto done_pages;
885 }
886
887 req->r_callback = rbd_cb;
888
889 req_data->rq = rq;
890 req_data->bio = bio;
891 req_data->pages = pages;
892 req_data->len = len;
893
894 req->r_priv = req_data;
895
896 reqhead = req->r_request->front.iov_base;
897 reqhead->snapid = cpu_to_le64(CEPH_NOSNAP);
898
899 strncpy(req->r_oid, obj, sizeof(req->r_oid));
900 req->r_oid_len = strlen(req->r_oid);
901
902 layout = &req->r_file_layout;
903 memset(layout, 0, sizeof(*layout));
904 layout->fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
905 layout->fl_stripe_count = cpu_to_le32(1);
906 layout->fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
907 layout->fl_pg_preferred = cpu_to_le32(-1);
908 layout->fl_pg_pool = cpu_to_le32(dev->poolid);
909 ceph_calc_raw_layout(&dev->client->osdc, layout, snapid,
910 ofs, &len, &bno, req, ops);
911
912 ceph_osdc_build_request(req, ofs, &len,
913 ops,
914 snapc,
915 &mtime,
916 req->r_oid, req->r_oid_len);
917 up_read(&header->snap_rwsem);
918
919 if (linger_req) {
920 ceph_osdc_set_request_linger(&dev->client->osdc, req);
921 *linger_req = req;
922 }
923
924 ret = ceph_osdc_start_request(&dev->client->osdc, req, false);
925 if (ret < 0)
926 goto done_err;
927
928 if (!rbd_cb) {
929 ret = ceph_osdc_wait_request(&dev->client->osdc, req);
930 if (ver)
931 *ver = le64_to_cpu(req->r_reassert_version.version);
932 dout("reassert_ver=%lld\n",
933 le64_to_cpu(req->r_reassert_version.version));
934 ceph_osdc_put_request(req);
935 }
936 return ret;
937
938done_err:
939 bio_chain_put(req_data->bio);
940 ceph_osdc_put_request(req);
941done_pages:
942 rbd_coll_end_req(req_data, ret, len);
943 kfree(req_data);
944 return ret;
945}
946
947/*
948 * Ceph osd op callback
949 */
950static void rbd_req_cb(struct ceph_osd_request *req, struct ceph_msg *msg)
951{
952 struct rbd_request *req_data = req->r_priv;
953 struct ceph_osd_reply_head *replyhead;
954 struct ceph_osd_op *op;
955 __s32 rc;
956 u64 bytes;
957 int read_op;
958
959 /* parse reply */
960 replyhead = msg->front.iov_base;
961 WARN_ON(le32_to_cpu(replyhead->num_ops) == 0);
962 op = (void *)(replyhead + 1);
963 rc = le32_to_cpu(replyhead->result);
964 bytes = le64_to_cpu(op->extent.length);
965 read_op = (le32_to_cpu(op->op) == CEPH_OSD_OP_READ);
966
967 dout("rbd_req_cb bytes=%lld readop=%d rc=%d\n", bytes, read_op, rc);
968
969 if (rc == -ENOENT && read_op) {
970 zero_bio_chain(req_data->bio, 0);
971 rc = 0;
972 } else if (rc == 0 && read_op && bytes < req_data->len) {
973 zero_bio_chain(req_data->bio, bytes);
974 bytes = req_data->len;
975 }
976
977 rbd_coll_end_req(req_data, rc, bytes);
978
979 if (req_data->bio)
980 bio_chain_put(req_data->bio);
981
982 ceph_osdc_put_request(req);
983 kfree(req_data);
984}
985
986static void rbd_simple_req_cb(struct ceph_osd_request *req, struct ceph_msg *msg)
987{
988 ceph_osdc_put_request(req);
989}
990
991/*
992 * Do a synchronous ceph osd operation
993 */
994static int rbd_req_sync_op(struct rbd_device *dev,
995 struct ceph_snap_context *snapc,
996 u64 snapid,
997 int opcode,
998 int flags,
999 struct ceph_osd_req_op *orig_ops,
1000 int num_reply,
1001 const char *obj,
1002 u64 ofs, u64 len,
1003 char *buf,
1004 struct ceph_osd_request **linger_req,
1005 u64 *ver)
1006{
1007 int ret;
1008 struct page **pages;
1009 int num_pages;
1010 struct ceph_osd_req_op *ops = orig_ops;
1011 u32 payload_len;
1012
1013 num_pages = calc_pages_for(ofs , len);
1014 pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
1015 if (IS_ERR(pages))
1016 return PTR_ERR(pages);
1017
1018 if (!orig_ops) {
1019 payload_len = (flags & CEPH_OSD_FLAG_WRITE ? len : 0);
1020 ret = rbd_create_rw_ops(&ops, 1, opcode, payload_len);
1021 if (ret < 0)
1022 goto done;
1023
1024 if ((flags & CEPH_OSD_FLAG_WRITE) && buf) {
1025 ret = ceph_copy_to_page_vector(pages, buf, ofs, len);
1026 if (ret < 0)
1027 goto done_ops;
1028 }
1029 }
1030
1031 ret = rbd_do_request(NULL, dev, snapc, snapid,
1032 obj, ofs, len, NULL,
1033 pages, num_pages,
1034 flags,
1035 ops,
1036 2,
1037 NULL, 0,
1038 NULL,
1039 linger_req, ver);
1040 if (ret < 0)
1041 goto done_ops;
1042
1043 if ((flags & CEPH_OSD_FLAG_READ) && buf)
1044 ret = ceph_copy_from_page_vector(pages, buf, ofs, ret);
1045
1046done_ops:
1047 if (!orig_ops)
1048 rbd_destroy_ops(ops);
1049done:
1050 ceph_release_page_vector(pages, num_pages);
1051 return ret;
1052}
1053
1054/*
1055 * Do an asynchronous ceph osd operation
1056 */
1057static int rbd_do_op(struct request *rq,
1058 struct rbd_device *rbd_dev ,
1059 struct ceph_snap_context *snapc,
1060 u64 snapid,
1061 int opcode, int flags, int num_reply,
1062 u64 ofs, u64 len,
1063 struct bio *bio,
1064 struct rbd_req_coll *coll,
1065 int coll_index)
1066{
1067 char *seg_name;
1068 u64 seg_ofs;
1069 u64 seg_len;
1070 int ret;
1071 struct ceph_osd_req_op *ops;
1072 u32 payload_len;
1073
1074 seg_name = kmalloc(RBD_MAX_SEG_NAME_LEN + 1, GFP_NOIO);
1075 if (!seg_name)
1076 return -ENOMEM;
1077
1078 seg_len = rbd_get_segment(&rbd_dev->header,
1079 rbd_dev->header.block_name,
1080 ofs, len,
1081 seg_name, &seg_ofs);
1082
1083 payload_len = (flags & CEPH_OSD_FLAG_WRITE ? seg_len : 0);
1084
1085 ret = rbd_create_rw_ops(&ops, 1, opcode, payload_len);
1086 if (ret < 0)
1087 goto done;
1088
1089 /* we've taken care of segment sizes earlier when we
1090 cloned the bios. We should never have a segment
1091 truncated at this point */
1092 BUG_ON(seg_len < len);
1093
1094 ret = rbd_do_request(rq, rbd_dev, snapc, snapid,
1095 seg_name, seg_ofs, seg_len,
1096 bio,
1097 NULL, 0,
1098 flags,
1099 ops,
1100 num_reply,
1101 coll, coll_index,
1102 rbd_req_cb, 0, NULL);
1103
1104 rbd_destroy_ops(ops);
1105done:
1106 kfree(seg_name);
1107 return ret;
1108}
1109
1110/*
1111 * Request async osd write
1112 */
1113static int rbd_req_write(struct request *rq,
1114 struct rbd_device *rbd_dev,
1115 struct ceph_snap_context *snapc,
1116 u64 ofs, u64 len,
1117 struct bio *bio,
1118 struct rbd_req_coll *coll,
1119 int coll_index)
1120{
1121 return rbd_do_op(rq, rbd_dev, snapc, CEPH_NOSNAP,
1122 CEPH_OSD_OP_WRITE,
1123 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1124 2,
1125 ofs, len, bio, coll, coll_index);
1126}
1127
1128/*
1129 * Request async osd read
1130 */
1131static int rbd_req_read(struct request *rq,
1132 struct rbd_device *rbd_dev,
1133 u64 snapid,
1134 u64 ofs, u64 len,
1135 struct bio *bio,
1136 struct rbd_req_coll *coll,
1137 int coll_index)
1138{
1139 return rbd_do_op(rq, rbd_dev, NULL,
1140 (snapid ? snapid : CEPH_NOSNAP),
1141 CEPH_OSD_OP_READ,
1142 CEPH_OSD_FLAG_READ,
1143 2,
1144 ofs, len, bio, coll, coll_index);
1145}
1146
1147/*
1148 * Request sync osd read
1149 */
1150static int rbd_req_sync_read(struct rbd_device *dev,
1151 struct ceph_snap_context *snapc,
1152 u64 snapid,
1153 const char *obj,
1154 u64 ofs, u64 len,
1155 char *buf,
1156 u64 *ver)
1157{
1158 return rbd_req_sync_op(dev, NULL,
1159 (snapid ? snapid : CEPH_NOSNAP),
1160 CEPH_OSD_OP_READ,
1161 CEPH_OSD_FLAG_READ,
1162 NULL,
1163 1, obj, ofs, len, buf, NULL, ver);
1164}
1165
1166/*
1167 * Request sync osd watch
1168 */
1169static int rbd_req_sync_notify_ack(struct rbd_device *dev,
1170 u64 ver,
1171 u64 notify_id,
1172 const char *obj)
1173{
1174 struct ceph_osd_req_op *ops;
1175 struct page **pages = NULL;
1176 int ret;
1177
1178 ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_NOTIFY_ACK, 0);
1179 if (ret < 0)
1180 return ret;
1181
1182 ops[0].watch.ver = cpu_to_le64(dev->header.obj_version);
1183 ops[0].watch.cookie = notify_id;
1184 ops[0].watch.flag = 0;
1185
1186 ret = rbd_do_request(NULL, dev, NULL, CEPH_NOSNAP,
1187 obj, 0, 0, NULL,
1188 pages, 0,
1189 CEPH_OSD_FLAG_READ,
1190 ops,
1191 1,
1192 NULL, 0,
1193 rbd_simple_req_cb, 0, NULL);
1194
1195 rbd_destroy_ops(ops);
1196 return ret;
1197}
1198
1199static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
1200{
1201 struct rbd_device *dev = (struct rbd_device *)data;
1202 int rc;
1203
1204 if (!dev)
1205 return;
1206
1207 dout("rbd_watch_cb %s notify_id=%lld opcode=%d\n", dev->obj_md_name,
1208 notify_id, (int)opcode);
1209 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
1210 rc = __rbd_update_snaps(dev);
1211 mutex_unlock(&ctl_mutex);
1212 if (rc)
1213 pr_warning(DRV_NAME "%d got notification but failed to update"
1214 " snaps: %d\n", dev->major, rc);
1215
1216 rbd_req_sync_notify_ack(dev, ver, notify_id, dev->obj_md_name);
1217}
1218
1219/*
1220 * Request sync osd watch
1221 */
1222static int rbd_req_sync_watch(struct rbd_device *dev,
1223 const char *obj,
1224 u64 ver)
1225{
1226 struct ceph_osd_req_op *ops;
1227 struct ceph_osd_client *osdc = &dev->client->osdc;
1228
1229 int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_WATCH, 0);
1230 if (ret < 0)
1231 return ret;
1232
1233 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, 0,
1234 (void *)dev, &dev->watch_event);
1235 if (ret < 0)
1236 goto fail;
1237
1238 ops[0].watch.ver = cpu_to_le64(ver);
1239 ops[0].watch.cookie = cpu_to_le64(dev->watch_event->cookie);
1240 ops[0].watch.flag = 1;
1241
1242 ret = rbd_req_sync_op(dev, NULL,
1243 CEPH_NOSNAP,
1244 0,
1245 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1246 ops,
1247 1, obj, 0, 0, NULL,
1248 &dev->watch_request, NULL);
1249
1250 if (ret < 0)
1251 goto fail_event;
1252
1253 rbd_destroy_ops(ops);
1254 return 0;
1255
1256fail_event:
1257 ceph_osdc_cancel_event(dev->watch_event);
1258 dev->watch_event = NULL;
1259fail:
1260 rbd_destroy_ops(ops);
1261 return ret;
1262}
1263
1264/*
1265 * Request sync osd unwatch
1266 */
1267static int rbd_req_sync_unwatch(struct rbd_device *dev,
1268 const char *obj)
1269{
1270 struct ceph_osd_req_op *ops;
1271
1272 int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_WATCH, 0);
1273 if (ret < 0)
1274 return ret;
1275
1276 ops[0].watch.ver = 0;
1277 ops[0].watch.cookie = cpu_to_le64(dev->watch_event->cookie);
1278 ops[0].watch.flag = 0;
1279
1280 ret = rbd_req_sync_op(dev, NULL,
1281 CEPH_NOSNAP,
1282 0,
1283 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1284 ops,
1285 1, obj, 0, 0, NULL, NULL, NULL);
1286
1287 rbd_destroy_ops(ops);
1288 ceph_osdc_cancel_event(dev->watch_event);
1289 dev->watch_event = NULL;
1290 return ret;
1291}
1292
1293struct rbd_notify_info {
1294 struct rbd_device *dev;
1295};
1296
1297static void rbd_notify_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
1298{
1299 struct rbd_device *dev = (struct rbd_device *)data;
1300 if (!dev)
1301 return;
1302
1303 dout("rbd_notify_cb %s notify_id=%lld opcode=%d\n", dev->obj_md_name,
1304 notify_id, (int)opcode);
1305}
1306
1307/*
1308 * Request sync osd notify
1309 */
1310static int rbd_req_sync_notify(struct rbd_device *dev,
1311 const char *obj)
1312{
1313 struct ceph_osd_req_op *ops;
1314 struct ceph_osd_client *osdc = &dev->client->osdc;
1315 struct ceph_osd_event *event;
1316 struct rbd_notify_info info;
1317 int payload_len = sizeof(u32) + sizeof(u32);
1318 int ret;
1319
1320 ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_NOTIFY, payload_len);
1321 if (ret < 0)
1322 return ret;
1323
1324 info.dev = dev;
1325
1326 ret = ceph_osdc_create_event(osdc, rbd_notify_cb, 1,
1327 (void *)&info, &event);
1328 if (ret < 0)
1329 goto fail;
1330
1331 ops[0].watch.ver = 1;
1332 ops[0].watch.flag = 1;
1333 ops[0].watch.cookie = event->cookie;
1334 ops[0].watch.prot_ver = RADOS_NOTIFY_VER;
1335 ops[0].watch.timeout = 12;
1336
1337 ret = rbd_req_sync_op(dev, NULL,
1338 CEPH_NOSNAP,
1339 0,
1340 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1341 ops,
1342 1, obj, 0, 0, NULL, NULL, NULL);
1343 if (ret < 0)
1344 goto fail_event;
1345
1346 ret = ceph_osdc_wait_event(event, CEPH_OSD_TIMEOUT_DEFAULT);
1347 dout("ceph_osdc_wait_event returned %d\n", ret);
1348 rbd_destroy_ops(ops);
1349 return 0;
1350
1351fail_event:
1352 ceph_osdc_cancel_event(event);
1353fail:
1354 rbd_destroy_ops(ops);
1355 return ret;
1356}
1357
1358/*
1359 * Request sync osd rollback
1360 */
1361static int rbd_req_sync_rollback_obj(struct rbd_device *dev,
1362 u64 snapid,
1363 const char *obj)
1364{
1365 struct ceph_osd_req_op *ops;
1366 int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_ROLLBACK, 0);
1367 if (ret < 0)
1368 return ret;
1369
1370 ops[0].snap.snapid = snapid;
1371
1372 ret = rbd_req_sync_op(dev, NULL,
1373 CEPH_NOSNAP,
1374 0,
1375 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1376 ops,
1377 1, obj, 0, 0, NULL, NULL, NULL);
1378
1379 rbd_destroy_ops(ops);
1380
1381 return ret;
1382}
1383
1384/*
1385 * Request sync osd read
1386 */
1387static int rbd_req_sync_exec(struct rbd_device *dev,
1388 const char *obj,
1389 const char *cls,
1390 const char *method,
1391 const char *data,
1392 int len,
1393 u64 *ver)
1394{
1395 struct ceph_osd_req_op *ops;
1396 int cls_len = strlen(cls);
1397 int method_len = strlen(method);
1398 int ret = rbd_create_rw_ops(&ops, 1, CEPH_OSD_OP_CALL,
1399 cls_len + method_len + len);
1400 if (ret < 0)
1401 return ret;
1402
1403 ops[0].cls.class_name = cls;
1404 ops[0].cls.class_len = (__u8)cls_len;
1405 ops[0].cls.method_name = method;
1406 ops[0].cls.method_len = (__u8)method_len;
1407 ops[0].cls.argc = 0;
1408 ops[0].cls.indata = data;
1409 ops[0].cls.indata_len = len;
1410
1411 ret = rbd_req_sync_op(dev, NULL,
1412 CEPH_NOSNAP,
1413 0,
1414 CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
1415 ops,
1416 1, obj, 0, 0, NULL, NULL, ver);
1417
1418 rbd_destroy_ops(ops);
1419
1420 dout("cls_exec returned %d\n", ret);
1421 return ret;
1422}
1423
1424static struct rbd_req_coll *rbd_alloc_coll(int num_reqs)
1425{
1426 struct rbd_req_coll *coll =
1427 kzalloc(sizeof(struct rbd_req_coll) +
1428 sizeof(struct rbd_req_status) * num_reqs,
1429 GFP_ATOMIC);
1430
1431 if (!coll)
1432 return NULL;
1433 coll->total = num_reqs;
1434 kref_init(&coll->kref);
1435 return coll;
1436}
1437
1438/*
1439 * block device queue callback
1440 */
1441static void rbd_rq_fn(struct request_queue *q)
1442{
1443 struct rbd_device *rbd_dev = q->queuedata;
1444 struct request *rq;
1445 struct bio_pair *bp = NULL;
1446
1447 rq = blk_fetch_request(q);
1448
1449 while (1) {
1450 struct bio *bio;
1451 struct bio *rq_bio, *next_bio = NULL;
1452 bool do_write;
1453 int size, op_size = 0;
1454 u64 ofs;
1455 int num_segs, cur_seg = 0;
1456 struct rbd_req_coll *coll;
1457
1458 /* peek at request from block layer */
1459 if (!rq)
1460 break;
1461
1462 dout("fetched request\n");
1463
1464 /* filter out block requests we don't understand */
1465 if ((rq->cmd_type != REQ_TYPE_FS)) {
1466 __blk_end_request_all(rq, 0);
1467 goto next;
1468 }
1469
1470 /* deduce our operation (read, write) */
1471 do_write = (rq_data_dir(rq) == WRITE);
1472
1473 size = blk_rq_bytes(rq);
1474 ofs = blk_rq_pos(rq) * 512ULL;
1475 rq_bio = rq->bio;
1476 if (do_write && rbd_dev->read_only) {
1477 __blk_end_request_all(rq, -EROFS);
1478 goto next;
1479 }
1480
1481 spin_unlock_irq(q->queue_lock);
1482
1483 dout("%s 0x%x bytes at 0x%llx\n",
1484 do_write ? "write" : "read",
1485 size, blk_rq_pos(rq) * 512ULL);
1486
1487 num_segs = rbd_get_num_segments(&rbd_dev->header, ofs, size);
1488 coll = rbd_alloc_coll(num_segs);
1489 if (!coll) {
1490 spin_lock_irq(q->queue_lock);
1491 __blk_end_request_all(rq, -ENOMEM);
1492 goto next;
1493 }
1494
1495 do {
1496 /* a bio clone to be passed down to OSD req */
1497 dout("rq->bio->bi_vcnt=%d\n", rq->bio->bi_vcnt);
1498 op_size = rbd_get_segment(&rbd_dev->header,
1499 rbd_dev->header.block_name,
1500 ofs, size,
1501 NULL, NULL);
1502 kref_get(&coll->kref);
1503 bio = bio_chain_clone(&rq_bio, &next_bio, &bp,
1504 op_size, GFP_ATOMIC);
1505 if (!bio) {
1506 rbd_coll_end_req_index(rq, coll, cur_seg,
1507 -ENOMEM, op_size);
1508 goto next_seg;
1509 }
1510
1511
1512 /* init OSD command: write or read */
1513 if (do_write)
1514 rbd_req_write(rq, rbd_dev,
1515 rbd_dev->header.snapc,
1516 ofs,
1517 op_size, bio,
1518 coll, cur_seg);
1519 else
1520 rbd_req_read(rq, rbd_dev,
1521 cur_snap_id(rbd_dev),
1522 ofs,
1523 op_size, bio,
1524 coll, cur_seg);
1525
1526next_seg:
1527 size -= op_size;
1528 ofs += op_size;
1529
1530 cur_seg++;
1531 rq_bio = next_bio;
1532 } while (size > 0);
1533 kref_put(&coll->kref, rbd_coll_release);
1534
1535 if (bp)
1536 bio_pair_release(bp);
1537 spin_lock_irq(q->queue_lock);
1538next:
1539 rq = blk_fetch_request(q);
1540 }
1541}
1542
1543/*
1544 * a queue callback. Makes sure that we don't create a bio that spans across
1545 * multiple osd objects. One exception would be with a single page bios,
1546 * which we handle later at bio_chain_clone
1547 */
1548static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
1549 struct bio_vec *bvec)
1550{
1551 struct rbd_device *rbd_dev = q->queuedata;
1552 unsigned int chunk_sectors = 1 << (rbd_dev->header.obj_order - 9);
1553 sector_t sector = bmd->bi_sector + get_start_sect(bmd->bi_bdev);
1554 unsigned int bio_sectors = bmd->bi_size >> 9;
1555 int max;
1556
1557 max = (chunk_sectors - ((sector & (chunk_sectors - 1))
1558 + bio_sectors)) << 9;
1559 if (max < 0)
1560 max = 0; /* bio_add cannot handle a negative return */
1561 if (max <= bvec->bv_len && bio_sectors == 0)
1562 return bvec->bv_len;
1563 return max;
1564}
1565
1566static void rbd_free_disk(struct rbd_device *rbd_dev)
1567{
1568 struct gendisk *disk = rbd_dev->disk;
1569
1570 if (!disk)
1571 return;
1572
1573 rbd_header_free(&rbd_dev->header);
1574
1575 if (disk->flags & GENHD_FL_UP)
1576 del_gendisk(disk);
1577 if (disk->queue)
1578 blk_cleanup_queue(disk->queue);
1579 put_disk(disk);
1580}
1581
1582/*
1583 * reload the ondisk the header
1584 */
1585static int rbd_read_header(struct rbd_device *rbd_dev,
1586 struct rbd_image_header *header)
1587{
1588 ssize_t rc;
1589 struct rbd_image_header_ondisk *dh;
1590 int snap_count = 0;
1591 u64 snap_names_len = 0;
1592 u64 ver;
1593
1594 while (1) {
1595 int len = sizeof(*dh) +
1596 snap_count * sizeof(struct rbd_image_snap_ondisk) +
1597 snap_names_len;
1598
1599 rc = -ENOMEM;
1600 dh = kmalloc(len, GFP_KERNEL);
1601 if (!dh)
1602 return -ENOMEM;
1603
1604 rc = rbd_req_sync_read(rbd_dev,
1605 NULL, CEPH_NOSNAP,
1606 rbd_dev->obj_md_name,
1607 0, len,
1608 (char *)dh, &ver);
1609 if (rc < 0)
1610 goto out_dh;
1611
1612 rc = rbd_header_from_disk(header, dh, snap_count, GFP_KERNEL);
1613 if (rc < 0)
1614 goto out_dh;
1615
1616 if (snap_count != header->total_snaps) {
1617 snap_count = header->total_snaps;
1618 snap_names_len = header->snap_names_len;
1619 rbd_header_free(header);
1620 kfree(dh);
1621 continue;
1622 }
1623 break;
1624 }
1625 header->obj_version = ver;
1626
1627out_dh:
1628 kfree(dh);
1629 return rc;
1630}
1631
1632/*
1633 * create a snapshot
1634 */
1635static int rbd_header_add_snap(struct rbd_device *dev,
1636 const char *snap_name,
1637 gfp_t gfp_flags)
1638{
1639 int name_len = strlen(snap_name);
1640 u64 new_snapid;
1641 int ret;
1642 void *data, *p, *e;
1643 u64 ver;
1644
1645 /* we should create a snapshot only if we're pointing at the head */
1646 if (dev->cur_snap)
1647 return -EINVAL;
1648
1649 ret = ceph_monc_create_snapid(&dev->client->monc, dev->poolid,
1650 &new_snapid);
1651 dout("created snapid=%lld\n", new_snapid);
1652 if (ret < 0)
1653 return ret;
1654
1655 data = kmalloc(name_len + 16, gfp_flags);
1656 if (!data)
1657 return -ENOMEM;
1658
1659 p = data;
1660 e = data + name_len + 16;
1661
1662 ceph_encode_string_safe(&p, e, snap_name, name_len, bad);
1663 ceph_encode_64_safe(&p, e, new_snapid, bad);
1664
1665 ret = rbd_req_sync_exec(dev, dev->obj_md_name, "rbd", "snap_add",
1666 data, p - data, &ver);
1667
1668 kfree(data);
1669
1670 if (ret < 0)
1671 return ret;
1672
1673 dev->header.snapc->seq = new_snapid;
1674
1675 return 0;
1676bad:
1677 return -ERANGE;
1678}
1679
1680static void __rbd_remove_all_snaps(struct rbd_device *rbd_dev)
1681{
1682 struct rbd_snap *snap;
1683
1684 while (!list_empty(&rbd_dev->snaps)) {
1685 snap = list_first_entry(&rbd_dev->snaps, struct rbd_snap, node);
1686 __rbd_remove_snap_dev(rbd_dev, snap);
1687 }
1688}
1689
1690/*
1691 * only read the first part of the ondisk header, without the snaps info
1692 */
1693static int __rbd_update_snaps(struct rbd_device *rbd_dev)
1694{
1695 int ret;
1696 struct rbd_image_header h;
1697 u64 snap_seq;
1698 int follow_seq = 0;
1699
1700 ret = rbd_read_header(rbd_dev, &h);
1701 if (ret < 0)
1702 return ret;
1703
1704 /* resized? */
1705 set_capacity(rbd_dev->disk, h.image_size / 512ULL);
1706
1707 down_write(&rbd_dev->header.snap_rwsem);
1708
1709 snap_seq = rbd_dev->header.snapc->seq;
1710 if (rbd_dev->header.total_snaps &&
1711 rbd_dev->header.snapc->snaps[0] == snap_seq)
1712 /* pointing at the head, will need to follow that
1713 if head moves */
1714 follow_seq = 1;
1715
1716 kfree(rbd_dev->header.snapc);
1717 kfree(rbd_dev->header.snap_names);
1718 kfree(rbd_dev->header.snap_sizes);
1719
1720 rbd_dev->header.total_snaps = h.total_snaps;
1721 rbd_dev->header.snapc = h.snapc;
1722 rbd_dev->header.snap_names = h.snap_names;
1723 rbd_dev->header.snap_names_len = h.snap_names_len;
1724 rbd_dev->header.snap_sizes = h.snap_sizes;
1725 if (follow_seq)
1726 rbd_dev->header.snapc->seq = rbd_dev->header.snapc->snaps[0];
1727 else
1728 rbd_dev->header.snapc->seq = snap_seq;
1729
1730 ret = __rbd_init_snaps_header(rbd_dev);
1731
1732 up_write(&rbd_dev->header.snap_rwsem);
1733
1734 return ret;
1735}
1736
1737static int rbd_init_disk(struct rbd_device *rbd_dev)
1738{
1739 struct gendisk *disk;
1740 struct request_queue *q;
1741 int rc;
1742 u64 total_size = 0;
1743
1744 /* contact OSD, request size info about the object being mapped */
1745 rc = rbd_read_header(rbd_dev, &rbd_dev->header);
1746 if (rc)
1747 return rc;
1748
1749 /* no need to lock here, as rbd_dev is not registered yet */
1750 rc = __rbd_init_snaps_header(rbd_dev);
1751 if (rc)
1752 return rc;
1753
1754 rc = rbd_header_set_snap(rbd_dev, rbd_dev->snap_name, &total_size);
1755 if (rc)
1756 return rc;
1757
1758 /* create gendisk info */
1759 rc = -ENOMEM;
1760 disk = alloc_disk(RBD_MINORS_PER_MAJOR);
1761 if (!disk)
1762 goto out;
1763
1764 snprintf(disk->disk_name, sizeof(disk->disk_name), DRV_NAME "%d",
1765 rbd_dev->id);
1766 disk->major = rbd_dev->major;
1767 disk->first_minor = 0;
1768 disk->fops = &rbd_bd_ops;
1769 disk->private_data = rbd_dev;
1770
1771 /* init rq */
1772 rc = -ENOMEM;
1773 q = blk_init_queue(rbd_rq_fn, &rbd_dev->lock);
1774 if (!q)
1775 goto out_disk;
1776
1777 /* set io sizes to object size */
1778 blk_queue_max_hw_sectors(q, rbd_obj_bytes(&rbd_dev->header) / 512ULL);
1779 blk_queue_max_segment_size(q, rbd_obj_bytes(&rbd_dev->header));
1780 blk_queue_io_min(q, rbd_obj_bytes(&rbd_dev->header));
1781 blk_queue_io_opt(q, rbd_obj_bytes(&rbd_dev->header));
1782
1783 blk_queue_merge_bvec(q, rbd_merge_bvec);
1784 disk->queue = q;
1785
1786 q->queuedata = rbd_dev;
1787
1788 rbd_dev->disk = disk;
1789 rbd_dev->q = q;
1790
1791 /* finally, announce the disk to the world */
1792 set_capacity(disk, total_size / 512ULL);
1793 add_disk(disk);
1794
1795 pr_info("%s: added with size 0x%llx\n",
1796 disk->disk_name, (unsigned long long)total_size);
1797 return 0;
1798
1799out_disk:
1800 put_disk(disk);
1801out:
1802 return rc;
1803}
1804
1805/*
1806 sysfs
1807*/
1808
1809static ssize_t rbd_size_show(struct device *dev,
1810 struct device_attribute *attr, char *buf)
1811{
1812 struct rbd_device *rbd_dev = dev_to_rbd(dev);
1813
1814 return sprintf(buf, "%llu\n", (unsigned long long)rbd_dev->header.image_size);
1815}
1816
1817static ssize_t rbd_major_show(struct device *dev,
1818 struct device_attribute *attr, char *buf)
1819{
1820 struct rbd_device *rbd_dev = dev_to_rbd(dev);
1821
1822 return sprintf(buf, "%d\n", rbd_dev->major);
1823}
1824
1825static ssize_t rbd_client_id_show(struct device *dev,
1826 struct device_attribute *attr, char *buf)
1827{
1828 struct rbd_device *rbd_dev = dev_to_rbd(dev);
1829
1830 return sprintf(buf, "client%lld\n", ceph_client_id(rbd_dev->client));
1831}
1832
1833static ssize_t rbd_pool_show(struct device *dev,
1834 struct device_attribute *attr, char *buf)
1835{
1836 struct rbd_device *rbd_dev = dev_to_rbd(dev);
1837
1838 return sprintf(buf, "%s\n", rbd_dev->pool_name);
1839}
1840
1841static ssize_t rbd_name_show(struct device *dev,
1842 struct device_attribute *attr, char *buf)
1843{
1844 struct rbd_device *rbd_dev = dev_to_rbd(dev);
1845
1846 return sprintf(buf, "%s\n", rbd_dev->obj);
1847}
1848
1849static ssize_t rbd_snap_show(struct device *dev,
1850 struct device_attribute *attr,
1851 char *buf)
1852{
1853 struct rbd_device *rbd_dev = dev_to_rbd(dev);
1854
1855 return sprintf(buf, "%s\n", rbd_dev->snap_name);
1856}
1857
1858static ssize_t rbd_image_refresh(struct device *dev,
1859 struct device_attribute *attr,
1860 const char *buf,
1861 size_t size)
1862{
1863 struct rbd_device *rbd_dev = dev_to_rbd(dev);
1864 int rc;
1865 int ret = size;
1866
1867 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
1868
1869 rc = __rbd_update_snaps(rbd_dev);
1870 if (rc < 0)
1871 ret = rc;
1872
1873 mutex_unlock(&ctl_mutex);
1874 return ret;
1875}
1876
1877static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
1878static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
1879static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
1880static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
1881static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
1882static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
1883static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
1884static DEVICE_ATTR(create_snap, S_IWUSR, NULL, rbd_snap_add);
1885static DEVICE_ATTR(rollback_snap, S_IWUSR, NULL, rbd_snap_rollback);
1886
1887static struct attribute *rbd_attrs[] = {
1888 &dev_attr_size.attr,
1889 &dev_attr_major.attr,
1890 &dev_attr_client_id.attr,
1891 &dev_attr_pool.attr,
1892 &dev_attr_name.attr,
1893 &dev_attr_current_snap.attr,
1894 &dev_attr_refresh.attr,
1895 &dev_attr_create_snap.attr,
1896 &dev_attr_rollback_snap.attr,
1897 NULL
1898};
1899
1900static struct attribute_group rbd_attr_group = {
1901 .attrs = rbd_attrs,
1902};
1903
1904static const struct attribute_group *rbd_attr_groups[] = {
1905 &rbd_attr_group,
1906 NULL
1907};
1908
1909static void rbd_sysfs_dev_release(struct device *dev)
1910{
1911}
1912
1913static struct device_type rbd_device_type = {
1914 .name = "rbd",
1915 .groups = rbd_attr_groups,
1916 .release = rbd_sysfs_dev_release,
1917};
1918
1919
1920/*
1921 sysfs - snapshots
1922*/
1923
1924static ssize_t rbd_snap_size_show(struct device *dev,
1925 struct device_attribute *attr,
1926 char *buf)
1927{
1928 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
1929
1930 return sprintf(buf, "%lld\n", (long long)snap->size);
1931}
1932
1933static ssize_t rbd_snap_id_show(struct device *dev,
1934 struct device_attribute *attr,
1935 char *buf)
1936{
1937 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
1938
1939 return sprintf(buf, "%lld\n", (long long)snap->id);
1940}
1941
1942static DEVICE_ATTR(snap_size, S_IRUGO, rbd_snap_size_show, NULL);
1943static DEVICE_ATTR(snap_id, S_IRUGO, rbd_snap_id_show, NULL);
1944
1945static struct attribute *rbd_snap_attrs[] = {
1946 &dev_attr_snap_size.attr,
1947 &dev_attr_snap_id.attr,
1948 NULL,
1949};
1950
1951static struct attribute_group rbd_snap_attr_group = {
1952 .attrs = rbd_snap_attrs,
1953};
1954
1955static void rbd_snap_dev_release(struct device *dev)
1956{
1957 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
1958 kfree(snap->name);
1959 kfree(snap);
1960}
1961
1962static const struct attribute_group *rbd_snap_attr_groups[] = {
1963 &rbd_snap_attr_group,
1964 NULL
1965};
1966
1967static struct device_type rbd_snap_device_type = {
1968 .groups = rbd_snap_attr_groups,
1969 .release = rbd_snap_dev_release,
1970};
1971
1972static void __rbd_remove_snap_dev(struct rbd_device *rbd_dev,
1973 struct rbd_snap *snap)
1974{
1975 list_del(&snap->node);
1976 device_unregister(&snap->dev);
1977}
1978
1979static int rbd_register_snap_dev(struct rbd_device *rbd_dev,
1980 struct rbd_snap *snap,
1981 struct device *parent)
1982{
1983 struct device *dev = &snap->dev;
1984 int ret;
1985
1986 dev->type = &rbd_snap_device_type;
1987 dev->parent = parent;
1988 dev->release = rbd_snap_dev_release;
1989 dev_set_name(dev, "snap_%s", snap->name);
1990 ret = device_register(dev);
1991
1992 return ret;
1993}
1994
1995static int __rbd_add_snap_dev(struct rbd_device *rbd_dev,
1996 int i, const char *name,
1997 struct rbd_snap **snapp)
1998{
1999 int ret;
2000 struct rbd_snap *snap = kzalloc(sizeof(*snap), GFP_KERNEL);
2001 if (!snap)
2002 return -ENOMEM;
2003 snap->name = kstrdup(name, GFP_KERNEL);
2004 snap->size = rbd_dev->header.snap_sizes[i];
2005 snap->id = rbd_dev->header.snapc->snaps[i];
2006 if (device_is_registered(&rbd_dev->dev)) {
2007 ret = rbd_register_snap_dev(rbd_dev, snap,
2008 &rbd_dev->dev);
2009 if (ret < 0)
2010 goto err;
2011 }
2012 *snapp = snap;
2013 return 0;
2014err:
2015 kfree(snap->name);
2016 kfree(snap);
2017 return ret;
2018}
2019
2020/*
2021 * search for the previous snap in a null delimited string list
2022 */
2023const char *rbd_prev_snap_name(const char *name, const char *start)
2024{
2025 if (name < start + 2)
2026 return NULL;
2027
2028 name -= 2;
2029 while (*name) {
2030 if (name == start)
2031 return start;
2032 name--;
2033 }
2034 return name + 1;
2035}
2036
2037/*
2038 * compare the old list of snapshots that we have to what's in the header
2039 * and update it accordingly. Note that the header holds the snapshots
2040 * in a reverse order (from newest to oldest) and we need to go from
2041 * older to new so that we don't get a duplicate snap name when
2042 * doing the process (e.g., removed snapshot and recreated a new
2043 * one with the same name.
2044 */
2045static int __rbd_init_snaps_header(struct rbd_device *rbd_dev)
2046{
2047 const char *name, *first_name;
2048 int i = rbd_dev->header.total_snaps;
2049 struct rbd_snap *snap, *old_snap = NULL;
2050 int ret;
2051 struct list_head *p, *n;
2052
2053 first_name = rbd_dev->header.snap_names;
2054 name = first_name + rbd_dev->header.snap_names_len;
2055
2056 list_for_each_prev_safe(p, n, &rbd_dev->snaps) {
2057 u64 cur_id;
2058
2059 old_snap = list_entry(p, struct rbd_snap, node);
2060
2061 if (i)
2062 cur_id = rbd_dev->header.snapc->snaps[i - 1];
2063
2064 if (!i || old_snap->id < cur_id) {
2065 /* old_snap->id was skipped, thus was removed */
2066 __rbd_remove_snap_dev(rbd_dev, old_snap);
2067 continue;
2068 }
2069 if (old_snap->id == cur_id) {
2070 /* we have this snapshot already */
2071 i--;
2072 name = rbd_prev_snap_name(name, first_name);
2073 continue;
2074 }
2075 for (; i > 0;
2076 i--, name = rbd_prev_snap_name(name, first_name)) {
2077 if (!name) {
2078 WARN_ON(1);
2079 return -EINVAL;
2080 }
2081 cur_id = rbd_dev->header.snapc->snaps[i];
2082 /* snapshot removal? handle it above */
2083 if (cur_id >= old_snap->id)
2084 break;
2085 /* a new snapshot */
2086 ret = __rbd_add_snap_dev(rbd_dev, i - 1, name, &snap);
2087 if (ret < 0)
2088 return ret;
2089
2090 /* note that we add it backward so using n and not p */
2091 list_add(&snap->node, n);
2092 p = &snap->node;
2093 }
2094 }
2095 /* we're done going over the old snap list, just add what's left */
2096 for (; i > 0; i--) {
2097 name = rbd_prev_snap_name(name, first_name);
2098 if (!name) {
2099 WARN_ON(1);
2100 return -EINVAL;
2101 }
2102 ret = __rbd_add_snap_dev(rbd_dev, i - 1, name, &snap);
2103 if (ret < 0)
2104 return ret;
2105 list_add(&snap->node, &rbd_dev->snaps);
2106 }
2107
2108 return 0;
2109}
2110
2111
2112static void rbd_root_dev_release(struct device *dev)
2113{
2114}
2115
2116static struct device rbd_root_dev = {
2117 .init_name = "rbd",
2118 .release = rbd_root_dev_release,
2119};
2120
2121static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
2122{
2123 int ret = -ENOMEM;
2124 struct device *dev;
2125 struct rbd_snap *snap;
2126
2127 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2128 dev = &rbd_dev->dev;
2129
2130 dev->bus = &rbd_bus_type;
2131 dev->type = &rbd_device_type;
2132 dev->parent = &rbd_root_dev;
2133 dev->release = rbd_dev_release;
2134 dev_set_name(dev, "%d", rbd_dev->id);
2135 ret = device_register(dev);
2136 if (ret < 0)
2137 goto done_free;
2138
2139 list_for_each_entry(snap, &rbd_dev->snaps, node) {
2140 ret = rbd_register_snap_dev(rbd_dev, snap,
2141 &rbd_dev->dev);
2142 if (ret < 0)
2143 break;
2144 }
2145
2146 mutex_unlock(&ctl_mutex);
2147 return 0;
2148done_free:
2149 mutex_unlock(&ctl_mutex);
2150 return ret;
2151}
2152
2153static void rbd_bus_del_dev(struct rbd_device *rbd_dev)
2154{
2155 device_unregister(&rbd_dev->dev);
2156}
2157
2158static int rbd_init_watch_dev(struct rbd_device *rbd_dev)
2159{
2160 int ret, rc;
2161
2162 do {
2163 ret = rbd_req_sync_watch(rbd_dev, rbd_dev->obj_md_name,
2164 rbd_dev->header.obj_version);
2165 if (ret == -ERANGE) {
2166 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2167 rc = __rbd_update_snaps(rbd_dev);
2168 mutex_unlock(&ctl_mutex);
2169 if (rc < 0)
2170 return rc;
2171 }
2172 } while (ret == -ERANGE);
2173
2174 return ret;
2175}
2176
2177static ssize_t rbd_add(struct bus_type *bus,
2178 const char *buf,
2179 size_t count)
2180{
2181 struct ceph_osd_client *osdc;
2182 struct rbd_device *rbd_dev;
2183 ssize_t rc = -ENOMEM;
2184 int irc, new_id = 0;
2185 struct list_head *tmp;
2186 char *mon_dev_name;
2187 char *options;
2188
2189 if (!try_module_get(THIS_MODULE))
2190 return -ENODEV;
2191
2192 mon_dev_name = kmalloc(RBD_MAX_OPT_LEN, GFP_KERNEL);
2193 if (!mon_dev_name)
2194 goto err_out_mod;
2195
2196 options = kmalloc(RBD_MAX_OPT_LEN, GFP_KERNEL);
2197 if (!options)
2198 goto err_mon_dev;
2199
2200 /* new rbd_device object */
2201 rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL);
2202 if (!rbd_dev)
2203 goto err_out_opt;
2204
2205 /* static rbd_device initialization */
2206 spin_lock_init(&rbd_dev->lock);
2207 INIT_LIST_HEAD(&rbd_dev->node);
2208 INIT_LIST_HEAD(&rbd_dev->snaps);
2209
2210 /* generate unique id: find highest unique id, add one */
2211 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2212
2213 list_for_each(tmp, &rbd_dev_list) {
2214 struct rbd_device *rbd_dev;
2215
2216 rbd_dev = list_entry(tmp, struct rbd_device, node);
2217 if (rbd_dev->id >= new_id)
2218 new_id = rbd_dev->id + 1;
2219 }
2220
2221 rbd_dev->id = new_id;
2222
2223 /* add to global list */
2224 list_add_tail(&rbd_dev->node, &rbd_dev_list);
2225
2226 /* parse add command */
2227 if (sscanf(buf, "%" __stringify(RBD_MAX_OPT_LEN) "s "
2228 "%" __stringify(RBD_MAX_OPT_LEN) "s "
2229 "%" __stringify(RBD_MAX_POOL_NAME_LEN) "s "
2230 "%" __stringify(RBD_MAX_OBJ_NAME_LEN) "s"
2231 "%" __stringify(RBD_MAX_SNAP_NAME_LEN) "s",
2232 mon_dev_name, options, rbd_dev->pool_name,
2233 rbd_dev->obj, rbd_dev->snap_name) < 4) {
2234 rc = -EINVAL;
2235 goto err_out_slot;
2236 }
2237
2238 if (rbd_dev->snap_name[0] == 0)
2239 rbd_dev->snap_name[0] = '-';
2240
2241 rbd_dev->obj_len = strlen(rbd_dev->obj);
2242 snprintf(rbd_dev->obj_md_name, sizeof(rbd_dev->obj_md_name), "%s%s",
2243 rbd_dev->obj, RBD_SUFFIX);
2244
2245 /* initialize rest of new object */
2246 snprintf(rbd_dev->name, DEV_NAME_LEN, DRV_NAME "%d", rbd_dev->id);
2247 rc = rbd_get_client(rbd_dev, mon_dev_name, options);
2248 if (rc < 0)
2249 goto err_out_slot;
2250
2251 mutex_unlock(&ctl_mutex);
2252
2253 /* pick the pool */
2254 osdc = &rbd_dev->client->osdc;
2255 rc = ceph_pg_poolid_by_name(osdc->osdmap, rbd_dev->pool_name);
2256 if (rc < 0)
2257 goto err_out_client;
2258 rbd_dev->poolid = rc;
2259
2260 /* register our block device */
2261 irc = register_blkdev(0, rbd_dev->name);
2262 if (irc < 0) {
2263 rc = irc;
2264 goto err_out_client;
2265 }
2266 rbd_dev->major = irc;
2267
2268 rc = rbd_bus_add_dev(rbd_dev);
2269 if (rc)
2270 goto err_out_blkdev;
2271
2272 /* set up and announce blkdev mapping */
2273 rc = rbd_init_disk(rbd_dev);
2274 if (rc)
2275 goto err_out_bus;
2276
2277 rc = rbd_init_watch_dev(rbd_dev);
2278 if (rc)
2279 goto err_out_bus;
2280
2281 return count;
2282
2283err_out_bus:
2284 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2285 list_del_init(&rbd_dev->node);
2286 mutex_unlock(&ctl_mutex);
2287
2288 /* this will also clean up rest of rbd_dev stuff */
2289
2290 rbd_bus_del_dev(rbd_dev);
2291 kfree(options);
2292 kfree(mon_dev_name);
2293 return rc;
2294
2295err_out_blkdev:
2296 unregister_blkdev(rbd_dev->major, rbd_dev->name);
2297err_out_client:
2298 rbd_put_client(rbd_dev);
2299 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2300err_out_slot:
2301 list_del_init(&rbd_dev->node);
2302 mutex_unlock(&ctl_mutex);
2303
2304 kfree(rbd_dev);
2305err_out_opt:
2306 kfree(options);
2307err_mon_dev:
2308 kfree(mon_dev_name);
2309err_out_mod:
2310 dout("Error adding device %s\n", buf);
2311 module_put(THIS_MODULE);
2312 return rc;
2313}
2314
2315static struct rbd_device *__rbd_get_dev(unsigned long id)
2316{
2317 struct list_head *tmp;
2318 struct rbd_device *rbd_dev;
2319
2320 list_for_each(tmp, &rbd_dev_list) {
2321 rbd_dev = list_entry(tmp, struct rbd_device, node);
2322 if (rbd_dev->id == id)
2323 return rbd_dev;
2324 }
2325 return NULL;
2326}
2327
2328static void rbd_dev_release(struct device *dev)
2329{
2330 struct rbd_device *rbd_dev =
2331 container_of(dev, struct rbd_device, dev);
2332
2333 if (rbd_dev->watch_request)
2334 ceph_osdc_unregister_linger_request(&rbd_dev->client->osdc,
2335 rbd_dev->watch_request);
2336 if (rbd_dev->watch_event)
2337 rbd_req_sync_unwatch(rbd_dev, rbd_dev->obj_md_name);
2338
2339 rbd_put_client(rbd_dev);
2340
2341 /* clean up and free blkdev */
2342 rbd_free_disk(rbd_dev);
2343 unregister_blkdev(rbd_dev->major, rbd_dev->name);
2344 kfree(rbd_dev);
2345
2346 /* release module ref */
2347 module_put(THIS_MODULE);
2348}
2349
2350static ssize_t rbd_remove(struct bus_type *bus,
2351 const char *buf,
2352 size_t count)
2353{
2354 struct rbd_device *rbd_dev = NULL;
2355 int target_id, rc;
2356 unsigned long ul;
2357 int ret = count;
2358
2359 rc = strict_strtoul(buf, 10, &ul);
2360 if (rc)
2361 return rc;
2362
2363 /* convert to int; abort if we lost anything in the conversion */
2364 target_id = (int) ul;
2365 if (target_id != ul)
2366 return -EINVAL;
2367
2368 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2369
2370 rbd_dev = __rbd_get_dev(target_id);
2371 if (!rbd_dev) {
2372 ret = -ENOENT;
2373 goto done;
2374 }
2375
2376 list_del_init(&rbd_dev->node);
2377
2378 __rbd_remove_all_snaps(rbd_dev);
2379 rbd_bus_del_dev(rbd_dev);
2380
2381done:
2382 mutex_unlock(&ctl_mutex);
2383 return ret;
2384}
2385
2386static ssize_t rbd_snap_add(struct device *dev,
2387 struct device_attribute *attr,
2388 const char *buf,
2389 size_t count)
2390{
2391 struct rbd_device *rbd_dev = dev_to_rbd(dev);
2392 int ret;
2393 char *name = kmalloc(count + 1, GFP_KERNEL);
2394 if (!name)
2395 return -ENOMEM;
2396
2397 snprintf(name, count, "%s", buf);
2398
2399 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2400
2401 ret = rbd_header_add_snap(rbd_dev,
2402 name, GFP_KERNEL);
2403 if (ret < 0)
2404 goto err_unlock;
2405
2406 ret = __rbd_update_snaps(rbd_dev);
2407 if (ret < 0)
2408 goto err_unlock;
2409
2410 /* shouldn't hold ctl_mutex when notifying.. notify might
2411 trigger a watch callback that would need to get that mutex */
2412 mutex_unlock(&ctl_mutex);
2413
2414 /* make a best effort, don't error if failed */
2415 rbd_req_sync_notify(rbd_dev, rbd_dev->obj_md_name);
2416
2417 ret = count;
2418 kfree(name);
2419 return ret;
2420
2421err_unlock:
2422 mutex_unlock(&ctl_mutex);
2423 kfree(name);
2424 return ret;
2425}
2426
2427static ssize_t rbd_snap_rollback(struct device *dev,
2428 struct device_attribute *attr,
2429 const char *buf,
2430 size_t count)
2431{
2432 struct rbd_device *rbd_dev = dev_to_rbd(dev);
2433 int ret;
2434 u64 snapid;
2435 u64 cur_ofs;
2436 char *seg_name = NULL;
2437 char *snap_name = kmalloc(count + 1, GFP_KERNEL);
2438 ret = -ENOMEM;
2439 if (!snap_name)
2440 return ret;
2441
2442 /* parse snaps add command */
2443 snprintf(snap_name, count, "%s", buf);
2444 seg_name = kmalloc(RBD_MAX_SEG_NAME_LEN + 1, GFP_NOIO);
2445 if (!seg_name)
2446 goto done;
2447
2448 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2449
2450 ret = snap_by_name(&rbd_dev->header, snap_name, &snapid, NULL);
2451 if (ret < 0)
2452 goto done_unlock;
2453
2454 dout("snapid=%lld\n", snapid);
2455
2456 cur_ofs = 0;
2457 while (cur_ofs < rbd_dev->header.image_size) {
2458 cur_ofs += rbd_get_segment(&rbd_dev->header,
2459 rbd_dev->obj,
2460 cur_ofs, (u64)-1,
2461 seg_name, NULL);
2462 dout("seg_name=%s\n", seg_name);
2463
2464 ret = rbd_req_sync_rollback_obj(rbd_dev, snapid, seg_name);
2465 if (ret < 0)
2466 pr_warning("could not roll back obj %s err=%d\n",
2467 seg_name, ret);
2468 }
2469
2470 ret = __rbd_update_snaps(rbd_dev);
2471 if (ret < 0)
2472 goto done_unlock;
2473
2474 ret = count;
2475
2476done_unlock:
2477 mutex_unlock(&ctl_mutex);
2478done:
2479 kfree(seg_name);
2480 kfree(snap_name);
2481
2482 return ret;
2483}
2484
2485static struct bus_attribute rbd_bus_attrs[] = {
2486 __ATTR(add, S_IWUSR, NULL, rbd_add),
2487 __ATTR(remove, S_IWUSR, NULL, rbd_remove),
2488 __ATTR_NULL
2489};
2490
2491/*
2492 * create control files in sysfs
2493 * /sys/bus/rbd/...
2494 */
2495static int rbd_sysfs_init(void)
2496{
2497 int ret;
2498
2499 rbd_bus_type.bus_attrs = rbd_bus_attrs;
2500
2501 ret = bus_register(&rbd_bus_type);
2502 if (ret < 0)
2503 return ret;
2504
2505 ret = device_register(&rbd_root_dev);
2506
2507 return ret;
2508}
2509
2510static void rbd_sysfs_cleanup(void)
2511{
2512 device_unregister(&rbd_root_dev);
2513 bus_unregister(&rbd_bus_type);
2514}
2515
2516int __init rbd_init(void)
2517{
2518 int rc;
2519
2520 rc = rbd_sysfs_init();
2521 if (rc)
2522 return rc;
2523 spin_lock_init(&node_lock);
2524 pr_info("loaded " DRV_NAME_LONG "\n");
2525 return 0;
2526}
2527
2528void __exit rbd_exit(void)
2529{
2530 rbd_sysfs_cleanup();
2531}
2532
2533module_init(rbd_init);
2534module_exit(rbd_exit);
2535
2536MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
2537MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
2538MODULE_DESCRIPTION("rados block device");
2539
2540/* following authorship retained from original osdblk.c */
2541MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
2542
2543MODULE_LICENSE("GPL");
1
2/*
3 rbd.c -- Export ceph rados objects as a Linux block device
4
5
6 based on drivers/block/osdblk.c:
7
8 Copyright 2009 Red Hat, Inc.
9
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program; see the file COPYING. If not, write to
21 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
22
23
24
25 For usage instructions, please refer to:
26
27 Documentation/ABI/testing/sysfs-bus-rbd
28
29 */
30
31#include <linux/ceph/libceph.h>
32#include <linux/ceph/osd_client.h>
33#include <linux/ceph/mon_client.h>
34#include <linux/ceph/cls_lock_client.h>
35#include <linux/ceph/striper.h>
36#include <linux/ceph/decode.h>
37#include <linux/fs_parser.h>
38#include <linux/bsearch.h>
39
40#include <linux/kernel.h>
41#include <linux/device.h>
42#include <linux/module.h>
43#include <linux/blk-mq.h>
44#include <linux/fs.h>
45#include <linux/blkdev.h>
46#include <linux/slab.h>
47#include <linux/idr.h>
48#include <linux/workqueue.h>
49
50#include "rbd_types.h"
51
52#define RBD_DEBUG /* Activate rbd_assert() calls */
53
54/*
55 * Increment the given counter and return its updated value.
56 * If the counter is already 0 it will not be incremented.
57 * If the counter is already at its maximum value returns
58 * -EINVAL without updating it.
59 */
60static int atomic_inc_return_safe(atomic_t *v)
61{
62 unsigned int counter;
63
64 counter = (unsigned int)atomic_fetch_add_unless(v, 1, 0);
65 if (counter <= (unsigned int)INT_MAX)
66 return (int)counter;
67
68 atomic_dec(v);
69
70 return -EINVAL;
71}
72
73/* Decrement the counter. Return the resulting value, or -EINVAL */
74static int atomic_dec_return_safe(atomic_t *v)
75{
76 int counter;
77
78 counter = atomic_dec_return(v);
79 if (counter >= 0)
80 return counter;
81
82 atomic_inc(v);
83
84 return -EINVAL;
85}
86
87#define RBD_DRV_NAME "rbd"
88
89#define RBD_MINORS_PER_MAJOR 256
90#define RBD_SINGLE_MAJOR_PART_SHIFT 4
91
92#define RBD_MAX_PARENT_CHAIN_LEN 16
93
94#define RBD_SNAP_DEV_NAME_PREFIX "snap_"
95#define RBD_MAX_SNAP_NAME_LEN \
96 (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1))
97
98#define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */
99
100#define RBD_SNAP_HEAD_NAME "-"
101
102#define BAD_SNAP_INDEX U32_MAX /* invalid index into snap array */
103
104/* This allows a single page to hold an image name sent by OSD */
105#define RBD_IMAGE_NAME_LEN_MAX (PAGE_SIZE - sizeof (__le32) - 1)
106#define RBD_IMAGE_ID_LEN_MAX 64
107
108#define RBD_OBJ_PREFIX_LEN_MAX 64
109
110#define RBD_NOTIFY_TIMEOUT 5 /* seconds */
111#define RBD_RETRY_DELAY msecs_to_jiffies(1000)
112
113/* Feature bits */
114
115#define RBD_FEATURE_LAYERING (1ULL<<0)
116#define RBD_FEATURE_STRIPINGV2 (1ULL<<1)
117#define RBD_FEATURE_EXCLUSIVE_LOCK (1ULL<<2)
118#define RBD_FEATURE_OBJECT_MAP (1ULL<<3)
119#define RBD_FEATURE_FAST_DIFF (1ULL<<4)
120#define RBD_FEATURE_DEEP_FLATTEN (1ULL<<5)
121#define RBD_FEATURE_DATA_POOL (1ULL<<7)
122#define RBD_FEATURE_OPERATIONS (1ULL<<8)
123
124#define RBD_FEATURES_ALL (RBD_FEATURE_LAYERING | \
125 RBD_FEATURE_STRIPINGV2 | \
126 RBD_FEATURE_EXCLUSIVE_LOCK | \
127 RBD_FEATURE_OBJECT_MAP | \
128 RBD_FEATURE_FAST_DIFF | \
129 RBD_FEATURE_DEEP_FLATTEN | \
130 RBD_FEATURE_DATA_POOL | \
131 RBD_FEATURE_OPERATIONS)
132
133/* Features supported by this (client software) implementation. */
134
135#define RBD_FEATURES_SUPPORTED (RBD_FEATURES_ALL)
136
137/*
138 * An RBD device name will be "rbd#", where the "rbd" comes from
139 * RBD_DRV_NAME above, and # is a unique integer identifier.
140 */
141#define DEV_NAME_LEN 32
142
143/*
144 * block device image metadata (in-memory version)
145 */
146struct rbd_image_header {
147 /* These six fields never change for a given rbd image */
148 char *object_prefix;
149 __u8 obj_order;
150 u64 stripe_unit;
151 u64 stripe_count;
152 s64 data_pool_id;
153 u64 features; /* Might be changeable someday? */
154
155 /* The remaining fields need to be updated occasionally */
156 u64 image_size;
157 struct ceph_snap_context *snapc;
158 char *snap_names; /* format 1 only */
159 u64 *snap_sizes; /* format 1 only */
160};
161
162/*
163 * An rbd image specification.
164 *
165 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely
166 * identify an image. Each rbd_dev structure includes a pointer to
167 * an rbd_spec structure that encapsulates this identity.
168 *
169 * Each of the id's in an rbd_spec has an associated name. For a
170 * user-mapped image, the names are supplied and the id's associated
171 * with them are looked up. For a layered image, a parent image is
172 * defined by the tuple, and the names are looked up.
173 *
174 * An rbd_dev structure contains a parent_spec pointer which is
175 * non-null if the image it represents is a child in a layered
176 * image. This pointer will refer to the rbd_spec structure used
177 * by the parent rbd_dev for its own identity (i.e., the structure
178 * is shared between the parent and child).
179 *
180 * Since these structures are populated once, during the discovery
181 * phase of image construction, they are effectively immutable so
182 * we make no effort to synchronize access to them.
183 *
184 * Note that code herein does not assume the image name is known (it
185 * could be a null pointer).
186 */
187struct rbd_spec {
188 u64 pool_id;
189 const char *pool_name;
190 const char *pool_ns; /* NULL if default, never "" */
191
192 const char *image_id;
193 const char *image_name;
194
195 u64 snap_id;
196 const char *snap_name;
197
198 struct kref kref;
199};
200
201/*
202 * an instance of the client. multiple devices may share an rbd client.
203 */
204struct rbd_client {
205 struct ceph_client *client;
206 struct kref kref;
207 struct list_head node;
208};
209
210struct pending_result {
211 int result; /* first nonzero result */
212 int num_pending;
213};
214
215struct rbd_img_request;
216
217enum obj_request_type {
218 OBJ_REQUEST_NODATA = 1,
219 OBJ_REQUEST_BIO, /* pointer into provided bio (list) */
220 OBJ_REQUEST_BVECS, /* pointer into provided bio_vec array */
221 OBJ_REQUEST_OWN_BVECS, /* private bio_vec array, doesn't own pages */
222};
223
224enum obj_operation_type {
225 OBJ_OP_READ = 1,
226 OBJ_OP_WRITE,
227 OBJ_OP_DISCARD,
228 OBJ_OP_ZEROOUT,
229};
230
231#define RBD_OBJ_FLAG_DELETION (1U << 0)
232#define RBD_OBJ_FLAG_COPYUP_ENABLED (1U << 1)
233#define RBD_OBJ_FLAG_COPYUP_ZEROS (1U << 2)
234#define RBD_OBJ_FLAG_MAY_EXIST (1U << 3)
235#define RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT (1U << 4)
236
237enum rbd_obj_read_state {
238 RBD_OBJ_READ_START = 1,
239 RBD_OBJ_READ_OBJECT,
240 RBD_OBJ_READ_PARENT,
241};
242
243/*
244 * Writes go through the following state machine to deal with
245 * layering:
246 *
247 * . . . . . RBD_OBJ_WRITE_GUARD. . . . . . . . . . . . . .
248 * . | .
249 * . v .
250 * . RBD_OBJ_WRITE_READ_FROM_PARENT. . . .
251 * . | . .
252 * . v v (deep-copyup .
253 * (image . RBD_OBJ_WRITE_COPYUP_EMPTY_SNAPC . not needed) .
254 * flattened) v | . .
255 * . v . .
256 * . . . .RBD_OBJ_WRITE_COPYUP_OPS. . . . . (copyup .
257 * | not needed) v
258 * v .
259 * done . . . . . . . . . . . . . . . . . .
260 * ^
261 * |
262 * RBD_OBJ_WRITE_FLAT
263 *
264 * Writes start in RBD_OBJ_WRITE_GUARD or _FLAT, depending on whether
265 * assert_exists guard is needed or not (in some cases it's not needed
266 * even if there is a parent).
267 */
268enum rbd_obj_write_state {
269 RBD_OBJ_WRITE_START = 1,
270 RBD_OBJ_WRITE_PRE_OBJECT_MAP,
271 RBD_OBJ_WRITE_OBJECT,
272 __RBD_OBJ_WRITE_COPYUP,
273 RBD_OBJ_WRITE_COPYUP,
274 RBD_OBJ_WRITE_POST_OBJECT_MAP,
275};
276
277enum rbd_obj_copyup_state {
278 RBD_OBJ_COPYUP_START = 1,
279 RBD_OBJ_COPYUP_READ_PARENT,
280 __RBD_OBJ_COPYUP_OBJECT_MAPS,
281 RBD_OBJ_COPYUP_OBJECT_MAPS,
282 __RBD_OBJ_COPYUP_WRITE_OBJECT,
283 RBD_OBJ_COPYUP_WRITE_OBJECT,
284};
285
286struct rbd_obj_request {
287 struct ceph_object_extent ex;
288 unsigned int flags; /* RBD_OBJ_FLAG_* */
289 union {
290 enum rbd_obj_read_state read_state; /* for reads */
291 enum rbd_obj_write_state write_state; /* for writes */
292 };
293
294 struct rbd_img_request *img_request;
295 struct ceph_file_extent *img_extents;
296 u32 num_img_extents;
297
298 union {
299 struct ceph_bio_iter bio_pos;
300 struct {
301 struct ceph_bvec_iter bvec_pos;
302 u32 bvec_count;
303 u32 bvec_idx;
304 };
305 };
306
307 enum rbd_obj_copyup_state copyup_state;
308 struct bio_vec *copyup_bvecs;
309 u32 copyup_bvec_count;
310
311 struct list_head osd_reqs; /* w/ r_private_item */
312
313 struct mutex state_mutex;
314 struct pending_result pending;
315 struct kref kref;
316};
317
318enum img_req_flags {
319 IMG_REQ_CHILD, /* initiator: block = 0, child image = 1 */
320 IMG_REQ_LAYERED, /* ENOENT handling: normal = 0, layered = 1 */
321};
322
323enum rbd_img_state {
324 RBD_IMG_START = 1,
325 RBD_IMG_EXCLUSIVE_LOCK,
326 __RBD_IMG_OBJECT_REQUESTS,
327 RBD_IMG_OBJECT_REQUESTS,
328};
329
330struct rbd_img_request {
331 struct rbd_device *rbd_dev;
332 enum obj_operation_type op_type;
333 enum obj_request_type data_type;
334 unsigned long flags;
335 enum rbd_img_state state;
336 union {
337 u64 snap_id; /* for reads */
338 struct ceph_snap_context *snapc; /* for writes */
339 };
340 struct rbd_obj_request *obj_request; /* obj req initiator */
341
342 struct list_head lock_item;
343 struct list_head object_extents; /* obj_req.ex structs */
344
345 struct mutex state_mutex;
346 struct pending_result pending;
347 struct work_struct work;
348 int work_result;
349};
350
351#define for_each_obj_request(ireq, oreq) \
352 list_for_each_entry(oreq, &(ireq)->object_extents, ex.oe_item)
353#define for_each_obj_request_safe(ireq, oreq, n) \
354 list_for_each_entry_safe(oreq, n, &(ireq)->object_extents, ex.oe_item)
355
356enum rbd_watch_state {
357 RBD_WATCH_STATE_UNREGISTERED,
358 RBD_WATCH_STATE_REGISTERED,
359 RBD_WATCH_STATE_ERROR,
360};
361
362enum rbd_lock_state {
363 RBD_LOCK_STATE_UNLOCKED,
364 RBD_LOCK_STATE_LOCKED,
365 RBD_LOCK_STATE_RELEASING,
366};
367
368/* WatchNotify::ClientId */
369struct rbd_client_id {
370 u64 gid;
371 u64 handle;
372};
373
374struct rbd_mapping {
375 u64 size;
376};
377
378/*
379 * a single device
380 */
381struct rbd_device {
382 int dev_id; /* blkdev unique id */
383
384 int major; /* blkdev assigned major */
385 int minor;
386 struct gendisk *disk; /* blkdev's gendisk and rq */
387
388 u32 image_format; /* Either 1 or 2 */
389 struct rbd_client *rbd_client;
390
391 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */
392
393 spinlock_t lock; /* queue, flags, open_count */
394
395 struct rbd_image_header header;
396 unsigned long flags; /* possibly lock protected */
397 struct rbd_spec *spec;
398 struct rbd_options *opts;
399 char *config_info; /* add{,_single_major} string */
400
401 struct ceph_object_id header_oid;
402 struct ceph_object_locator header_oloc;
403
404 struct ceph_file_layout layout; /* used for all rbd requests */
405
406 struct mutex watch_mutex;
407 enum rbd_watch_state watch_state;
408 struct ceph_osd_linger_request *watch_handle;
409 u64 watch_cookie;
410 struct delayed_work watch_dwork;
411
412 struct rw_semaphore lock_rwsem;
413 enum rbd_lock_state lock_state;
414 char lock_cookie[32];
415 struct rbd_client_id owner_cid;
416 struct work_struct acquired_lock_work;
417 struct work_struct released_lock_work;
418 struct delayed_work lock_dwork;
419 struct work_struct unlock_work;
420 spinlock_t lock_lists_lock;
421 struct list_head acquiring_list;
422 struct list_head running_list;
423 struct completion acquire_wait;
424 int acquire_err;
425 struct completion releasing_wait;
426
427 spinlock_t object_map_lock;
428 u8 *object_map;
429 u64 object_map_size; /* in objects */
430 u64 object_map_flags;
431
432 struct workqueue_struct *task_wq;
433
434 struct rbd_spec *parent_spec;
435 u64 parent_overlap;
436 atomic_t parent_ref;
437 struct rbd_device *parent;
438
439 /* Block layer tags. */
440 struct blk_mq_tag_set tag_set;
441
442 /* protects updating the header */
443 struct rw_semaphore header_rwsem;
444
445 struct rbd_mapping mapping;
446
447 struct list_head node;
448
449 /* sysfs related */
450 struct device dev;
451 unsigned long open_count; /* protected by lock */
452};
453
454/*
455 * Flag bits for rbd_dev->flags:
456 * - REMOVING (which is coupled with rbd_dev->open_count) is protected
457 * by rbd_dev->lock
458 */
459enum rbd_dev_flags {
460 RBD_DEV_FLAG_EXISTS, /* rbd_dev_device_setup() ran */
461 RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */
462 RBD_DEV_FLAG_READONLY, /* -o ro or snapshot */
463};
464
465static DEFINE_MUTEX(client_mutex); /* Serialize client creation */
466
467static LIST_HEAD(rbd_dev_list); /* devices */
468static DEFINE_SPINLOCK(rbd_dev_list_lock);
469
470static LIST_HEAD(rbd_client_list); /* clients */
471static DEFINE_SPINLOCK(rbd_client_list_lock);
472
473/* Slab caches for frequently-allocated structures */
474
475static struct kmem_cache *rbd_img_request_cache;
476static struct kmem_cache *rbd_obj_request_cache;
477
478static int rbd_major;
479static DEFINE_IDA(rbd_dev_id_ida);
480
481static struct workqueue_struct *rbd_wq;
482
483static struct ceph_snap_context rbd_empty_snapc = {
484 .nref = REFCOUNT_INIT(1),
485};
486
487/*
488 * single-major requires >= 0.75 version of userspace rbd utility.
489 */
490static bool single_major = true;
491module_param(single_major, bool, 0444);
492MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: true)");
493
494static ssize_t add_store(struct bus_type *bus, const char *buf, size_t count);
495static ssize_t remove_store(struct bus_type *bus, const char *buf,
496 size_t count);
497static ssize_t add_single_major_store(struct bus_type *bus, const char *buf,
498 size_t count);
499static ssize_t remove_single_major_store(struct bus_type *bus, const char *buf,
500 size_t count);
501static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth);
502
503static int rbd_dev_id_to_minor(int dev_id)
504{
505 return dev_id << RBD_SINGLE_MAJOR_PART_SHIFT;
506}
507
508static int minor_to_rbd_dev_id(int minor)
509{
510 return minor >> RBD_SINGLE_MAJOR_PART_SHIFT;
511}
512
513static bool rbd_is_ro(struct rbd_device *rbd_dev)
514{
515 return test_bit(RBD_DEV_FLAG_READONLY, &rbd_dev->flags);
516}
517
518static bool rbd_is_snap(struct rbd_device *rbd_dev)
519{
520 return rbd_dev->spec->snap_id != CEPH_NOSNAP;
521}
522
523static bool __rbd_is_lock_owner(struct rbd_device *rbd_dev)
524{
525 lockdep_assert_held(&rbd_dev->lock_rwsem);
526
527 return rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED ||
528 rbd_dev->lock_state == RBD_LOCK_STATE_RELEASING;
529}
530
531static bool rbd_is_lock_owner(struct rbd_device *rbd_dev)
532{
533 bool is_lock_owner;
534
535 down_read(&rbd_dev->lock_rwsem);
536 is_lock_owner = __rbd_is_lock_owner(rbd_dev);
537 up_read(&rbd_dev->lock_rwsem);
538 return is_lock_owner;
539}
540
541static ssize_t supported_features_show(struct bus_type *bus, char *buf)
542{
543 return sprintf(buf, "0x%llx\n", RBD_FEATURES_SUPPORTED);
544}
545
546static BUS_ATTR_WO(add);
547static BUS_ATTR_WO(remove);
548static BUS_ATTR_WO(add_single_major);
549static BUS_ATTR_WO(remove_single_major);
550static BUS_ATTR_RO(supported_features);
551
552static struct attribute *rbd_bus_attrs[] = {
553 &bus_attr_add.attr,
554 &bus_attr_remove.attr,
555 &bus_attr_add_single_major.attr,
556 &bus_attr_remove_single_major.attr,
557 &bus_attr_supported_features.attr,
558 NULL,
559};
560
561static umode_t rbd_bus_is_visible(struct kobject *kobj,
562 struct attribute *attr, int index)
563{
564 if (!single_major &&
565 (attr == &bus_attr_add_single_major.attr ||
566 attr == &bus_attr_remove_single_major.attr))
567 return 0;
568
569 return attr->mode;
570}
571
572static const struct attribute_group rbd_bus_group = {
573 .attrs = rbd_bus_attrs,
574 .is_visible = rbd_bus_is_visible,
575};
576__ATTRIBUTE_GROUPS(rbd_bus);
577
578static struct bus_type rbd_bus_type = {
579 .name = "rbd",
580 .bus_groups = rbd_bus_groups,
581};
582
583static void rbd_root_dev_release(struct device *dev)
584{
585}
586
587static struct device rbd_root_dev = {
588 .init_name = "rbd",
589 .release = rbd_root_dev_release,
590};
591
592static __printf(2, 3)
593void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...)
594{
595 struct va_format vaf;
596 va_list args;
597
598 va_start(args, fmt);
599 vaf.fmt = fmt;
600 vaf.va = &args;
601
602 if (!rbd_dev)
603 printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf);
604 else if (rbd_dev->disk)
605 printk(KERN_WARNING "%s: %s: %pV\n",
606 RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf);
607 else if (rbd_dev->spec && rbd_dev->spec->image_name)
608 printk(KERN_WARNING "%s: image %s: %pV\n",
609 RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf);
610 else if (rbd_dev->spec && rbd_dev->spec->image_id)
611 printk(KERN_WARNING "%s: id %s: %pV\n",
612 RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf);
613 else /* punt */
614 printk(KERN_WARNING "%s: rbd_dev %p: %pV\n",
615 RBD_DRV_NAME, rbd_dev, &vaf);
616 va_end(args);
617}
618
619#ifdef RBD_DEBUG
620#define rbd_assert(expr) \
621 if (unlikely(!(expr))) { \
622 printk(KERN_ERR "\nAssertion failure in %s() " \
623 "at line %d:\n\n" \
624 "\trbd_assert(%s);\n\n", \
625 __func__, __LINE__, #expr); \
626 BUG(); \
627 }
628#else /* !RBD_DEBUG */
629# define rbd_assert(expr) ((void) 0)
630#endif /* !RBD_DEBUG */
631
632static void rbd_dev_remove_parent(struct rbd_device *rbd_dev);
633
634static int rbd_dev_refresh(struct rbd_device *rbd_dev);
635static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev);
636static int rbd_dev_header_info(struct rbd_device *rbd_dev);
637static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev);
638static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
639 u64 snap_id);
640static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
641 u8 *order, u64 *snap_size);
642static int rbd_dev_v2_get_flags(struct rbd_device *rbd_dev);
643
644static void rbd_obj_handle_request(struct rbd_obj_request *obj_req, int result);
645static void rbd_img_handle_request(struct rbd_img_request *img_req, int result);
646
647/*
648 * Return true if nothing else is pending.
649 */
650static bool pending_result_dec(struct pending_result *pending, int *result)
651{
652 rbd_assert(pending->num_pending > 0);
653
654 if (*result && !pending->result)
655 pending->result = *result;
656 if (--pending->num_pending)
657 return false;
658
659 *result = pending->result;
660 return true;
661}
662
663static int rbd_open(struct block_device *bdev, fmode_t mode)
664{
665 struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
666 bool removing = false;
667
668 spin_lock_irq(&rbd_dev->lock);
669 if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags))
670 removing = true;
671 else
672 rbd_dev->open_count++;
673 spin_unlock_irq(&rbd_dev->lock);
674 if (removing)
675 return -ENOENT;
676
677 (void) get_device(&rbd_dev->dev);
678
679 return 0;
680}
681
682static void rbd_release(struct gendisk *disk, fmode_t mode)
683{
684 struct rbd_device *rbd_dev = disk->private_data;
685 unsigned long open_count_before;
686
687 spin_lock_irq(&rbd_dev->lock);
688 open_count_before = rbd_dev->open_count--;
689 spin_unlock_irq(&rbd_dev->lock);
690 rbd_assert(open_count_before > 0);
691
692 put_device(&rbd_dev->dev);
693}
694
695static const struct block_device_operations rbd_bd_ops = {
696 .owner = THIS_MODULE,
697 .open = rbd_open,
698 .release = rbd_release,
699};
700
701/*
702 * Initialize an rbd client instance. Success or not, this function
703 * consumes ceph_opts. Caller holds client_mutex.
704 */
705static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
706{
707 struct rbd_client *rbdc;
708 int ret = -ENOMEM;
709
710 dout("%s:\n", __func__);
711 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
712 if (!rbdc)
713 goto out_opt;
714
715 kref_init(&rbdc->kref);
716 INIT_LIST_HEAD(&rbdc->node);
717
718 rbdc->client = ceph_create_client(ceph_opts, rbdc);
719 if (IS_ERR(rbdc->client))
720 goto out_rbdc;
721 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
722
723 ret = ceph_open_session(rbdc->client);
724 if (ret < 0)
725 goto out_client;
726
727 spin_lock(&rbd_client_list_lock);
728 list_add_tail(&rbdc->node, &rbd_client_list);
729 spin_unlock(&rbd_client_list_lock);
730
731 dout("%s: rbdc %p\n", __func__, rbdc);
732
733 return rbdc;
734out_client:
735 ceph_destroy_client(rbdc->client);
736out_rbdc:
737 kfree(rbdc);
738out_opt:
739 if (ceph_opts)
740 ceph_destroy_options(ceph_opts);
741 dout("%s: error %d\n", __func__, ret);
742
743 return ERR_PTR(ret);
744}
745
746static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
747{
748 kref_get(&rbdc->kref);
749
750 return rbdc;
751}
752
753/*
754 * Find a ceph client with specific addr and configuration. If
755 * found, bump its reference count.
756 */
757static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
758{
759 struct rbd_client *client_node;
760 bool found = false;
761
762 if (ceph_opts->flags & CEPH_OPT_NOSHARE)
763 return NULL;
764
765 spin_lock(&rbd_client_list_lock);
766 list_for_each_entry(client_node, &rbd_client_list, node) {
767 if (!ceph_compare_options(ceph_opts, client_node->client)) {
768 __rbd_get_client(client_node);
769
770 found = true;
771 break;
772 }
773 }
774 spin_unlock(&rbd_client_list_lock);
775
776 return found ? client_node : NULL;
777}
778
779/*
780 * (Per device) rbd map options
781 */
782enum {
783 Opt_queue_depth,
784 Opt_alloc_size,
785 Opt_lock_timeout,
786 /* int args above */
787 Opt_pool_ns,
788 Opt_compression_hint,
789 /* string args above */
790 Opt_read_only,
791 Opt_read_write,
792 Opt_lock_on_read,
793 Opt_exclusive,
794 Opt_notrim,
795};
796
797enum {
798 Opt_compression_hint_none,
799 Opt_compression_hint_compressible,
800 Opt_compression_hint_incompressible,
801};
802
803static const struct constant_table rbd_param_compression_hint[] = {
804 {"none", Opt_compression_hint_none},
805 {"compressible", Opt_compression_hint_compressible},
806 {"incompressible", Opt_compression_hint_incompressible},
807 {}
808};
809
810static const struct fs_parameter_spec rbd_parameters[] = {
811 fsparam_u32 ("alloc_size", Opt_alloc_size),
812 fsparam_enum ("compression_hint", Opt_compression_hint,
813 rbd_param_compression_hint),
814 fsparam_flag ("exclusive", Opt_exclusive),
815 fsparam_flag ("lock_on_read", Opt_lock_on_read),
816 fsparam_u32 ("lock_timeout", Opt_lock_timeout),
817 fsparam_flag ("notrim", Opt_notrim),
818 fsparam_string ("_pool_ns", Opt_pool_ns),
819 fsparam_u32 ("queue_depth", Opt_queue_depth),
820 fsparam_flag ("read_only", Opt_read_only),
821 fsparam_flag ("read_write", Opt_read_write),
822 fsparam_flag ("ro", Opt_read_only),
823 fsparam_flag ("rw", Opt_read_write),
824 {}
825};
826
827struct rbd_options {
828 int queue_depth;
829 int alloc_size;
830 unsigned long lock_timeout;
831 bool read_only;
832 bool lock_on_read;
833 bool exclusive;
834 bool trim;
835
836 u32 alloc_hint_flags; /* CEPH_OSD_OP_ALLOC_HINT_FLAG_* */
837};
838
839#define RBD_QUEUE_DEPTH_DEFAULT BLKDEV_MAX_RQ
840#define RBD_ALLOC_SIZE_DEFAULT (64 * 1024)
841#define RBD_LOCK_TIMEOUT_DEFAULT 0 /* no timeout */
842#define RBD_READ_ONLY_DEFAULT false
843#define RBD_LOCK_ON_READ_DEFAULT false
844#define RBD_EXCLUSIVE_DEFAULT false
845#define RBD_TRIM_DEFAULT true
846
847struct rbd_parse_opts_ctx {
848 struct rbd_spec *spec;
849 struct ceph_options *copts;
850 struct rbd_options *opts;
851};
852
853static char* obj_op_name(enum obj_operation_type op_type)
854{
855 switch (op_type) {
856 case OBJ_OP_READ:
857 return "read";
858 case OBJ_OP_WRITE:
859 return "write";
860 case OBJ_OP_DISCARD:
861 return "discard";
862 case OBJ_OP_ZEROOUT:
863 return "zeroout";
864 default:
865 return "???";
866 }
867}
868
869/*
870 * Destroy ceph client
871 *
872 * Caller must hold rbd_client_list_lock.
873 */
874static void rbd_client_release(struct kref *kref)
875{
876 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
877
878 dout("%s: rbdc %p\n", __func__, rbdc);
879 spin_lock(&rbd_client_list_lock);
880 list_del(&rbdc->node);
881 spin_unlock(&rbd_client_list_lock);
882
883 ceph_destroy_client(rbdc->client);
884 kfree(rbdc);
885}
886
887/*
888 * Drop reference to ceph client node. If it's not referenced anymore, release
889 * it.
890 */
891static void rbd_put_client(struct rbd_client *rbdc)
892{
893 if (rbdc)
894 kref_put(&rbdc->kref, rbd_client_release);
895}
896
897/*
898 * Get a ceph client with specific addr and configuration, if one does
899 * not exist create it. Either way, ceph_opts is consumed by this
900 * function.
901 */
902static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
903{
904 struct rbd_client *rbdc;
905 int ret;
906
907 mutex_lock(&client_mutex);
908 rbdc = rbd_client_find(ceph_opts);
909 if (rbdc) {
910 ceph_destroy_options(ceph_opts);
911
912 /*
913 * Using an existing client. Make sure ->pg_pools is up to
914 * date before we look up the pool id in do_rbd_add().
915 */
916 ret = ceph_wait_for_latest_osdmap(rbdc->client,
917 rbdc->client->options->mount_timeout);
918 if (ret) {
919 rbd_warn(NULL, "failed to get latest osdmap: %d", ret);
920 rbd_put_client(rbdc);
921 rbdc = ERR_PTR(ret);
922 }
923 } else {
924 rbdc = rbd_client_create(ceph_opts);
925 }
926 mutex_unlock(&client_mutex);
927
928 return rbdc;
929}
930
931static bool rbd_image_format_valid(u32 image_format)
932{
933 return image_format == 1 || image_format == 2;
934}
935
936static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
937{
938 size_t size;
939 u32 snap_count;
940
941 /* The header has to start with the magic rbd header text */
942 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
943 return false;
944
945 /* The bio layer requires at least sector-sized I/O */
946
947 if (ondisk->options.order < SECTOR_SHIFT)
948 return false;
949
950 /* If we use u64 in a few spots we may be able to loosen this */
951
952 if (ondisk->options.order > 8 * sizeof (int) - 1)
953 return false;
954
955 /*
956 * The size of a snapshot header has to fit in a size_t, and
957 * that limits the number of snapshots.
958 */
959 snap_count = le32_to_cpu(ondisk->snap_count);
960 size = SIZE_MAX - sizeof (struct ceph_snap_context);
961 if (snap_count > size / sizeof (__le64))
962 return false;
963
964 /*
965 * Not only that, but the size of the entire the snapshot
966 * header must also be representable in a size_t.
967 */
968 size -= snap_count * sizeof (__le64);
969 if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
970 return false;
971
972 return true;
973}
974
975/*
976 * returns the size of an object in the image
977 */
978static u32 rbd_obj_bytes(struct rbd_image_header *header)
979{
980 return 1U << header->obj_order;
981}
982
983static void rbd_init_layout(struct rbd_device *rbd_dev)
984{
985 if (rbd_dev->header.stripe_unit == 0 ||
986 rbd_dev->header.stripe_count == 0) {
987 rbd_dev->header.stripe_unit = rbd_obj_bytes(&rbd_dev->header);
988 rbd_dev->header.stripe_count = 1;
989 }
990
991 rbd_dev->layout.stripe_unit = rbd_dev->header.stripe_unit;
992 rbd_dev->layout.stripe_count = rbd_dev->header.stripe_count;
993 rbd_dev->layout.object_size = rbd_obj_bytes(&rbd_dev->header);
994 rbd_dev->layout.pool_id = rbd_dev->header.data_pool_id == CEPH_NOPOOL ?
995 rbd_dev->spec->pool_id : rbd_dev->header.data_pool_id;
996 RCU_INIT_POINTER(rbd_dev->layout.pool_ns, NULL);
997}
998
999/*
1000 * Fill an rbd image header with information from the given format 1
1001 * on-disk header.
1002 */
1003static int rbd_header_from_disk(struct rbd_device *rbd_dev,
1004 struct rbd_image_header_ondisk *ondisk)
1005{
1006 struct rbd_image_header *header = &rbd_dev->header;
1007 bool first_time = header->object_prefix == NULL;
1008 struct ceph_snap_context *snapc;
1009 char *object_prefix = NULL;
1010 char *snap_names = NULL;
1011 u64 *snap_sizes = NULL;
1012 u32 snap_count;
1013 int ret = -ENOMEM;
1014 u32 i;
1015
1016 /* Allocate this now to avoid having to handle failure below */
1017
1018 if (first_time) {
1019 object_prefix = kstrndup(ondisk->object_prefix,
1020 sizeof(ondisk->object_prefix),
1021 GFP_KERNEL);
1022 if (!object_prefix)
1023 return -ENOMEM;
1024 }
1025
1026 /* Allocate the snapshot context and fill it in */
1027
1028 snap_count = le32_to_cpu(ondisk->snap_count);
1029 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
1030 if (!snapc)
1031 goto out_err;
1032 snapc->seq = le64_to_cpu(ondisk->snap_seq);
1033 if (snap_count) {
1034 struct rbd_image_snap_ondisk *snaps;
1035 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);
1036
1037 /* We'll keep a copy of the snapshot names... */
1038
1039 if (snap_names_len > (u64)SIZE_MAX)
1040 goto out_2big;
1041 snap_names = kmalloc(snap_names_len, GFP_KERNEL);
1042 if (!snap_names)
1043 goto out_err;
1044
1045 /* ...as well as the array of their sizes. */
1046 snap_sizes = kmalloc_array(snap_count,
1047 sizeof(*header->snap_sizes),
1048 GFP_KERNEL);
1049 if (!snap_sizes)
1050 goto out_err;
1051
1052 /*
1053 * Copy the names, and fill in each snapshot's id
1054 * and size.
1055 *
1056 * Note that rbd_dev_v1_header_info() guarantees the
1057 * ondisk buffer we're working with has
1058 * snap_names_len bytes beyond the end of the
1059 * snapshot id array, this memcpy() is safe.
1060 */
1061 memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len);
1062 snaps = ondisk->snaps;
1063 for (i = 0; i < snap_count; i++) {
1064 snapc->snaps[i] = le64_to_cpu(snaps[i].id);
1065 snap_sizes[i] = le64_to_cpu(snaps[i].image_size);
1066 }
1067 }
1068
1069 /* We won't fail any more, fill in the header */
1070
1071 if (first_time) {
1072 header->object_prefix = object_prefix;
1073 header->obj_order = ondisk->options.order;
1074 rbd_init_layout(rbd_dev);
1075 } else {
1076 ceph_put_snap_context(header->snapc);
1077 kfree(header->snap_names);
1078 kfree(header->snap_sizes);
1079 }
1080
1081 /* The remaining fields always get updated (when we refresh) */
1082
1083 header->image_size = le64_to_cpu(ondisk->image_size);
1084 header->snapc = snapc;
1085 header->snap_names = snap_names;
1086 header->snap_sizes = snap_sizes;
1087
1088 return 0;
1089out_2big:
1090 ret = -EIO;
1091out_err:
1092 kfree(snap_sizes);
1093 kfree(snap_names);
1094 ceph_put_snap_context(snapc);
1095 kfree(object_prefix);
1096
1097 return ret;
1098}
1099
1100static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
1101{
1102 const char *snap_name;
1103
1104 rbd_assert(which < rbd_dev->header.snapc->num_snaps);
1105
1106 /* Skip over names until we find the one we are looking for */
1107
1108 snap_name = rbd_dev->header.snap_names;
1109 while (which--)
1110 snap_name += strlen(snap_name) + 1;
1111
1112 return kstrdup(snap_name, GFP_KERNEL);
1113}
1114
1115/*
1116 * Snapshot id comparison function for use with qsort()/bsearch().
1117 * Note that result is for snapshots in *descending* order.
1118 */
1119static int snapid_compare_reverse(const void *s1, const void *s2)
1120{
1121 u64 snap_id1 = *(u64 *)s1;
1122 u64 snap_id2 = *(u64 *)s2;
1123
1124 if (snap_id1 < snap_id2)
1125 return 1;
1126 return snap_id1 == snap_id2 ? 0 : -1;
1127}
1128
1129/*
1130 * Search a snapshot context to see if the given snapshot id is
1131 * present.
1132 *
1133 * Returns the position of the snapshot id in the array if it's found,
1134 * or BAD_SNAP_INDEX otherwise.
1135 *
1136 * Note: The snapshot array is in kept sorted (by the osd) in
1137 * reverse order, highest snapshot id first.
1138 */
1139static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id)
1140{
1141 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
1142 u64 *found;
1143
1144 found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps,
1145 sizeof (snap_id), snapid_compare_reverse);
1146
1147 return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX;
1148}
1149
1150static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
1151 u64 snap_id)
1152{
1153 u32 which;
1154 const char *snap_name;
1155
1156 which = rbd_dev_snap_index(rbd_dev, snap_id);
1157 if (which == BAD_SNAP_INDEX)
1158 return ERR_PTR(-ENOENT);
1159
1160 snap_name = _rbd_dev_v1_snap_name(rbd_dev, which);
1161 return snap_name ? snap_name : ERR_PTR(-ENOMEM);
1162}
1163
1164static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
1165{
1166 if (snap_id == CEPH_NOSNAP)
1167 return RBD_SNAP_HEAD_NAME;
1168
1169 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1170 if (rbd_dev->image_format == 1)
1171 return rbd_dev_v1_snap_name(rbd_dev, snap_id);
1172
1173 return rbd_dev_v2_snap_name(rbd_dev, snap_id);
1174}
1175
1176static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
1177 u64 *snap_size)
1178{
1179 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1180 if (snap_id == CEPH_NOSNAP) {
1181 *snap_size = rbd_dev->header.image_size;
1182 } else if (rbd_dev->image_format == 1) {
1183 u32 which;
1184
1185 which = rbd_dev_snap_index(rbd_dev, snap_id);
1186 if (which == BAD_SNAP_INDEX)
1187 return -ENOENT;
1188
1189 *snap_size = rbd_dev->header.snap_sizes[which];
1190 } else {
1191 u64 size = 0;
1192 int ret;
1193
1194 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
1195 if (ret)
1196 return ret;
1197
1198 *snap_size = size;
1199 }
1200 return 0;
1201}
1202
1203static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
1204{
1205 u64 snap_id = rbd_dev->spec->snap_id;
1206 u64 size = 0;
1207 int ret;
1208
1209 ret = rbd_snap_size(rbd_dev, snap_id, &size);
1210 if (ret)
1211 return ret;
1212
1213 rbd_dev->mapping.size = size;
1214 return 0;
1215}
1216
1217static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
1218{
1219 rbd_dev->mapping.size = 0;
1220}
1221
1222static void zero_bvec(struct bio_vec *bv)
1223{
1224 void *buf;
1225 unsigned long flags;
1226
1227 buf = bvec_kmap_irq(bv, &flags);
1228 memset(buf, 0, bv->bv_len);
1229 flush_dcache_page(bv->bv_page);
1230 bvec_kunmap_irq(buf, &flags);
1231}
1232
1233static void zero_bios(struct ceph_bio_iter *bio_pos, u32 off, u32 bytes)
1234{
1235 struct ceph_bio_iter it = *bio_pos;
1236
1237 ceph_bio_iter_advance(&it, off);
1238 ceph_bio_iter_advance_step(&it, bytes, ({
1239 zero_bvec(&bv);
1240 }));
1241}
1242
1243static void zero_bvecs(struct ceph_bvec_iter *bvec_pos, u32 off, u32 bytes)
1244{
1245 struct ceph_bvec_iter it = *bvec_pos;
1246
1247 ceph_bvec_iter_advance(&it, off);
1248 ceph_bvec_iter_advance_step(&it, bytes, ({
1249 zero_bvec(&bv);
1250 }));
1251}
1252
1253/*
1254 * Zero a range in @obj_req data buffer defined by a bio (list) or
1255 * (private) bio_vec array.
1256 *
1257 * @off is relative to the start of the data buffer.
1258 */
1259static void rbd_obj_zero_range(struct rbd_obj_request *obj_req, u32 off,
1260 u32 bytes)
1261{
1262 dout("%s %p data buf %u~%u\n", __func__, obj_req, off, bytes);
1263
1264 switch (obj_req->img_request->data_type) {
1265 case OBJ_REQUEST_BIO:
1266 zero_bios(&obj_req->bio_pos, off, bytes);
1267 break;
1268 case OBJ_REQUEST_BVECS:
1269 case OBJ_REQUEST_OWN_BVECS:
1270 zero_bvecs(&obj_req->bvec_pos, off, bytes);
1271 break;
1272 default:
1273 BUG();
1274 }
1275}
1276
1277static void rbd_obj_request_destroy(struct kref *kref);
1278static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
1279{
1280 rbd_assert(obj_request != NULL);
1281 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1282 kref_read(&obj_request->kref));
1283 kref_put(&obj_request->kref, rbd_obj_request_destroy);
1284}
1285
1286static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
1287 struct rbd_obj_request *obj_request)
1288{
1289 rbd_assert(obj_request->img_request == NULL);
1290
1291 /* Image request now owns object's original reference */
1292 obj_request->img_request = img_request;
1293 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
1294}
1295
1296static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
1297 struct rbd_obj_request *obj_request)
1298{
1299 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
1300 list_del(&obj_request->ex.oe_item);
1301 rbd_assert(obj_request->img_request == img_request);
1302 rbd_obj_request_put(obj_request);
1303}
1304
1305static void rbd_osd_submit(struct ceph_osd_request *osd_req)
1306{
1307 struct rbd_obj_request *obj_req = osd_req->r_priv;
1308
1309 dout("%s osd_req %p for obj_req %p objno %llu %llu~%llu\n",
1310 __func__, osd_req, obj_req, obj_req->ex.oe_objno,
1311 obj_req->ex.oe_off, obj_req->ex.oe_len);
1312 ceph_osdc_start_request(osd_req->r_osdc, osd_req, false);
1313}
1314
1315/*
1316 * The default/initial value for all image request flags is 0. Each
1317 * is conditionally set to 1 at image request initialization time
1318 * and currently never change thereafter.
1319 */
1320static void img_request_layered_set(struct rbd_img_request *img_request)
1321{
1322 set_bit(IMG_REQ_LAYERED, &img_request->flags);
1323}
1324
1325static bool img_request_layered_test(struct rbd_img_request *img_request)
1326{
1327 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
1328}
1329
1330static bool rbd_obj_is_entire(struct rbd_obj_request *obj_req)
1331{
1332 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1333
1334 return !obj_req->ex.oe_off &&
1335 obj_req->ex.oe_len == rbd_dev->layout.object_size;
1336}
1337
1338static bool rbd_obj_is_tail(struct rbd_obj_request *obj_req)
1339{
1340 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1341
1342 return obj_req->ex.oe_off + obj_req->ex.oe_len ==
1343 rbd_dev->layout.object_size;
1344}
1345
1346/*
1347 * Must be called after rbd_obj_calc_img_extents().
1348 */
1349static bool rbd_obj_copyup_enabled(struct rbd_obj_request *obj_req)
1350{
1351 if (!obj_req->num_img_extents ||
1352 (rbd_obj_is_entire(obj_req) &&
1353 !obj_req->img_request->snapc->num_snaps))
1354 return false;
1355
1356 return true;
1357}
1358
1359static u64 rbd_obj_img_extents_bytes(struct rbd_obj_request *obj_req)
1360{
1361 return ceph_file_extents_bytes(obj_req->img_extents,
1362 obj_req->num_img_extents);
1363}
1364
1365static bool rbd_img_is_write(struct rbd_img_request *img_req)
1366{
1367 switch (img_req->op_type) {
1368 case OBJ_OP_READ:
1369 return false;
1370 case OBJ_OP_WRITE:
1371 case OBJ_OP_DISCARD:
1372 case OBJ_OP_ZEROOUT:
1373 return true;
1374 default:
1375 BUG();
1376 }
1377}
1378
1379static void rbd_osd_req_callback(struct ceph_osd_request *osd_req)
1380{
1381 struct rbd_obj_request *obj_req = osd_req->r_priv;
1382 int result;
1383
1384 dout("%s osd_req %p result %d for obj_req %p\n", __func__, osd_req,
1385 osd_req->r_result, obj_req);
1386
1387 /*
1388 * Writes aren't allowed to return a data payload. In some
1389 * guarded write cases (e.g. stat + zero on an empty object)
1390 * a stat response makes it through, but we don't care.
1391 */
1392 if (osd_req->r_result > 0 && rbd_img_is_write(obj_req->img_request))
1393 result = 0;
1394 else
1395 result = osd_req->r_result;
1396
1397 rbd_obj_handle_request(obj_req, result);
1398}
1399
1400static void rbd_osd_format_read(struct ceph_osd_request *osd_req)
1401{
1402 struct rbd_obj_request *obj_request = osd_req->r_priv;
1403 struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev;
1404 struct ceph_options *opt = rbd_dev->rbd_client->client->options;
1405
1406 osd_req->r_flags = CEPH_OSD_FLAG_READ | opt->read_from_replica;
1407 osd_req->r_snapid = obj_request->img_request->snap_id;
1408}
1409
1410static void rbd_osd_format_write(struct ceph_osd_request *osd_req)
1411{
1412 struct rbd_obj_request *obj_request = osd_req->r_priv;
1413
1414 osd_req->r_flags = CEPH_OSD_FLAG_WRITE;
1415 ktime_get_real_ts64(&osd_req->r_mtime);
1416 osd_req->r_data_offset = obj_request->ex.oe_off;
1417}
1418
1419static struct ceph_osd_request *
1420__rbd_obj_add_osd_request(struct rbd_obj_request *obj_req,
1421 struct ceph_snap_context *snapc, int num_ops)
1422{
1423 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1424 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1425 struct ceph_osd_request *req;
1426 const char *name_format = rbd_dev->image_format == 1 ?
1427 RBD_V1_DATA_FORMAT : RBD_V2_DATA_FORMAT;
1428 int ret;
1429
1430 req = ceph_osdc_alloc_request(osdc, snapc, num_ops, false, GFP_NOIO);
1431 if (!req)
1432 return ERR_PTR(-ENOMEM);
1433
1434 list_add_tail(&req->r_private_item, &obj_req->osd_reqs);
1435 req->r_callback = rbd_osd_req_callback;
1436 req->r_priv = obj_req;
1437
1438 /*
1439 * Data objects may be stored in a separate pool, but always in
1440 * the same namespace in that pool as the header in its pool.
1441 */
1442 ceph_oloc_copy(&req->r_base_oloc, &rbd_dev->header_oloc);
1443 req->r_base_oloc.pool = rbd_dev->layout.pool_id;
1444
1445 ret = ceph_oid_aprintf(&req->r_base_oid, GFP_NOIO, name_format,
1446 rbd_dev->header.object_prefix,
1447 obj_req->ex.oe_objno);
1448 if (ret)
1449 return ERR_PTR(ret);
1450
1451 return req;
1452}
1453
1454static struct ceph_osd_request *
1455rbd_obj_add_osd_request(struct rbd_obj_request *obj_req, int num_ops)
1456{
1457 return __rbd_obj_add_osd_request(obj_req, obj_req->img_request->snapc,
1458 num_ops);
1459}
1460
1461static struct rbd_obj_request *rbd_obj_request_create(void)
1462{
1463 struct rbd_obj_request *obj_request;
1464
1465 obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_NOIO);
1466 if (!obj_request)
1467 return NULL;
1468
1469 ceph_object_extent_init(&obj_request->ex);
1470 INIT_LIST_HEAD(&obj_request->osd_reqs);
1471 mutex_init(&obj_request->state_mutex);
1472 kref_init(&obj_request->kref);
1473
1474 dout("%s %p\n", __func__, obj_request);
1475 return obj_request;
1476}
1477
1478static void rbd_obj_request_destroy(struct kref *kref)
1479{
1480 struct rbd_obj_request *obj_request;
1481 struct ceph_osd_request *osd_req;
1482 u32 i;
1483
1484 obj_request = container_of(kref, struct rbd_obj_request, kref);
1485
1486 dout("%s: obj %p\n", __func__, obj_request);
1487
1488 while (!list_empty(&obj_request->osd_reqs)) {
1489 osd_req = list_first_entry(&obj_request->osd_reqs,
1490 struct ceph_osd_request, r_private_item);
1491 list_del_init(&osd_req->r_private_item);
1492 ceph_osdc_put_request(osd_req);
1493 }
1494
1495 switch (obj_request->img_request->data_type) {
1496 case OBJ_REQUEST_NODATA:
1497 case OBJ_REQUEST_BIO:
1498 case OBJ_REQUEST_BVECS:
1499 break; /* Nothing to do */
1500 case OBJ_REQUEST_OWN_BVECS:
1501 kfree(obj_request->bvec_pos.bvecs);
1502 break;
1503 default:
1504 BUG();
1505 }
1506
1507 kfree(obj_request->img_extents);
1508 if (obj_request->copyup_bvecs) {
1509 for (i = 0; i < obj_request->copyup_bvec_count; i++) {
1510 if (obj_request->copyup_bvecs[i].bv_page)
1511 __free_page(obj_request->copyup_bvecs[i].bv_page);
1512 }
1513 kfree(obj_request->copyup_bvecs);
1514 }
1515
1516 kmem_cache_free(rbd_obj_request_cache, obj_request);
1517}
1518
1519/* It's OK to call this for a device with no parent */
1520
1521static void rbd_spec_put(struct rbd_spec *spec);
1522static void rbd_dev_unparent(struct rbd_device *rbd_dev)
1523{
1524 rbd_dev_remove_parent(rbd_dev);
1525 rbd_spec_put(rbd_dev->parent_spec);
1526 rbd_dev->parent_spec = NULL;
1527 rbd_dev->parent_overlap = 0;
1528}
1529
1530/*
1531 * Parent image reference counting is used to determine when an
1532 * image's parent fields can be safely torn down--after there are no
1533 * more in-flight requests to the parent image. When the last
1534 * reference is dropped, cleaning them up is safe.
1535 */
1536static void rbd_dev_parent_put(struct rbd_device *rbd_dev)
1537{
1538 int counter;
1539
1540 if (!rbd_dev->parent_spec)
1541 return;
1542
1543 counter = atomic_dec_return_safe(&rbd_dev->parent_ref);
1544 if (counter > 0)
1545 return;
1546
1547 /* Last reference; clean up parent data structures */
1548
1549 if (!counter)
1550 rbd_dev_unparent(rbd_dev);
1551 else
1552 rbd_warn(rbd_dev, "parent reference underflow");
1553}
1554
1555/*
1556 * If an image has a non-zero parent overlap, get a reference to its
1557 * parent.
1558 *
1559 * Returns true if the rbd device has a parent with a non-zero
1560 * overlap and a reference for it was successfully taken, or
1561 * false otherwise.
1562 */
1563static bool rbd_dev_parent_get(struct rbd_device *rbd_dev)
1564{
1565 int counter = 0;
1566
1567 if (!rbd_dev->parent_spec)
1568 return false;
1569
1570 if (rbd_dev->parent_overlap)
1571 counter = atomic_inc_return_safe(&rbd_dev->parent_ref);
1572
1573 if (counter < 0)
1574 rbd_warn(rbd_dev, "parent reference overflow");
1575
1576 return counter > 0;
1577}
1578
1579static void rbd_img_request_init(struct rbd_img_request *img_request,
1580 struct rbd_device *rbd_dev,
1581 enum obj_operation_type op_type)
1582{
1583 memset(img_request, 0, sizeof(*img_request));
1584
1585 img_request->rbd_dev = rbd_dev;
1586 img_request->op_type = op_type;
1587
1588 INIT_LIST_HEAD(&img_request->lock_item);
1589 INIT_LIST_HEAD(&img_request->object_extents);
1590 mutex_init(&img_request->state_mutex);
1591}
1592
1593static void rbd_img_capture_header(struct rbd_img_request *img_req)
1594{
1595 struct rbd_device *rbd_dev = img_req->rbd_dev;
1596
1597 lockdep_assert_held(&rbd_dev->header_rwsem);
1598
1599 if (rbd_img_is_write(img_req))
1600 img_req->snapc = ceph_get_snap_context(rbd_dev->header.snapc);
1601 else
1602 img_req->snap_id = rbd_dev->spec->snap_id;
1603
1604 if (rbd_dev_parent_get(rbd_dev))
1605 img_request_layered_set(img_req);
1606}
1607
1608static void rbd_img_request_destroy(struct rbd_img_request *img_request)
1609{
1610 struct rbd_obj_request *obj_request;
1611 struct rbd_obj_request *next_obj_request;
1612
1613 dout("%s: img %p\n", __func__, img_request);
1614
1615 WARN_ON(!list_empty(&img_request->lock_item));
1616 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
1617 rbd_img_obj_request_del(img_request, obj_request);
1618
1619 if (img_request_layered_test(img_request))
1620 rbd_dev_parent_put(img_request->rbd_dev);
1621
1622 if (rbd_img_is_write(img_request))
1623 ceph_put_snap_context(img_request->snapc);
1624
1625 if (test_bit(IMG_REQ_CHILD, &img_request->flags))
1626 kmem_cache_free(rbd_img_request_cache, img_request);
1627}
1628
1629#define BITS_PER_OBJ 2
1630#define OBJS_PER_BYTE (BITS_PER_BYTE / BITS_PER_OBJ)
1631#define OBJ_MASK ((1 << BITS_PER_OBJ) - 1)
1632
1633static void __rbd_object_map_index(struct rbd_device *rbd_dev, u64 objno,
1634 u64 *index, u8 *shift)
1635{
1636 u32 off;
1637
1638 rbd_assert(objno < rbd_dev->object_map_size);
1639 *index = div_u64_rem(objno, OBJS_PER_BYTE, &off);
1640 *shift = (OBJS_PER_BYTE - off - 1) * BITS_PER_OBJ;
1641}
1642
1643static u8 __rbd_object_map_get(struct rbd_device *rbd_dev, u64 objno)
1644{
1645 u64 index;
1646 u8 shift;
1647
1648 lockdep_assert_held(&rbd_dev->object_map_lock);
1649 __rbd_object_map_index(rbd_dev, objno, &index, &shift);
1650 return (rbd_dev->object_map[index] >> shift) & OBJ_MASK;
1651}
1652
1653static void __rbd_object_map_set(struct rbd_device *rbd_dev, u64 objno, u8 val)
1654{
1655 u64 index;
1656 u8 shift;
1657 u8 *p;
1658
1659 lockdep_assert_held(&rbd_dev->object_map_lock);
1660 rbd_assert(!(val & ~OBJ_MASK));
1661
1662 __rbd_object_map_index(rbd_dev, objno, &index, &shift);
1663 p = &rbd_dev->object_map[index];
1664 *p = (*p & ~(OBJ_MASK << shift)) | (val << shift);
1665}
1666
1667static u8 rbd_object_map_get(struct rbd_device *rbd_dev, u64 objno)
1668{
1669 u8 state;
1670
1671 spin_lock(&rbd_dev->object_map_lock);
1672 state = __rbd_object_map_get(rbd_dev, objno);
1673 spin_unlock(&rbd_dev->object_map_lock);
1674 return state;
1675}
1676
1677static bool use_object_map(struct rbd_device *rbd_dev)
1678{
1679 /*
1680 * An image mapped read-only can't use the object map -- it isn't
1681 * loaded because the header lock isn't acquired. Someone else can
1682 * write to the image and update the object map behind our back.
1683 *
1684 * A snapshot can't be written to, so using the object map is always
1685 * safe.
1686 */
1687 if (!rbd_is_snap(rbd_dev) && rbd_is_ro(rbd_dev))
1688 return false;
1689
1690 return ((rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP) &&
1691 !(rbd_dev->object_map_flags & RBD_FLAG_OBJECT_MAP_INVALID));
1692}
1693
1694static bool rbd_object_map_may_exist(struct rbd_device *rbd_dev, u64 objno)
1695{
1696 u8 state;
1697
1698 /* fall back to default logic if object map is disabled or invalid */
1699 if (!use_object_map(rbd_dev))
1700 return true;
1701
1702 state = rbd_object_map_get(rbd_dev, objno);
1703 return state != OBJECT_NONEXISTENT;
1704}
1705
1706static void rbd_object_map_name(struct rbd_device *rbd_dev, u64 snap_id,
1707 struct ceph_object_id *oid)
1708{
1709 if (snap_id == CEPH_NOSNAP)
1710 ceph_oid_printf(oid, "%s%s", RBD_OBJECT_MAP_PREFIX,
1711 rbd_dev->spec->image_id);
1712 else
1713 ceph_oid_printf(oid, "%s%s.%016llx", RBD_OBJECT_MAP_PREFIX,
1714 rbd_dev->spec->image_id, snap_id);
1715}
1716
1717static int rbd_object_map_lock(struct rbd_device *rbd_dev)
1718{
1719 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1720 CEPH_DEFINE_OID_ONSTACK(oid);
1721 u8 lock_type;
1722 char *lock_tag;
1723 struct ceph_locker *lockers;
1724 u32 num_lockers;
1725 bool broke_lock = false;
1726 int ret;
1727
1728 rbd_object_map_name(rbd_dev, CEPH_NOSNAP, &oid);
1729
1730again:
1731 ret = ceph_cls_lock(osdc, &oid, &rbd_dev->header_oloc, RBD_LOCK_NAME,
1732 CEPH_CLS_LOCK_EXCLUSIVE, "", "", "", 0);
1733 if (ret != -EBUSY || broke_lock) {
1734 if (ret == -EEXIST)
1735 ret = 0; /* already locked by myself */
1736 if (ret)
1737 rbd_warn(rbd_dev, "failed to lock object map: %d", ret);
1738 return ret;
1739 }
1740
1741 ret = ceph_cls_lock_info(osdc, &oid, &rbd_dev->header_oloc,
1742 RBD_LOCK_NAME, &lock_type, &lock_tag,
1743 &lockers, &num_lockers);
1744 if (ret) {
1745 if (ret == -ENOENT)
1746 goto again;
1747
1748 rbd_warn(rbd_dev, "failed to get object map lockers: %d", ret);
1749 return ret;
1750 }
1751
1752 kfree(lock_tag);
1753 if (num_lockers == 0)
1754 goto again;
1755
1756 rbd_warn(rbd_dev, "breaking object map lock owned by %s%llu",
1757 ENTITY_NAME(lockers[0].id.name));
1758
1759 ret = ceph_cls_break_lock(osdc, &oid, &rbd_dev->header_oloc,
1760 RBD_LOCK_NAME, lockers[0].id.cookie,
1761 &lockers[0].id.name);
1762 ceph_free_lockers(lockers, num_lockers);
1763 if (ret) {
1764 if (ret == -ENOENT)
1765 goto again;
1766
1767 rbd_warn(rbd_dev, "failed to break object map lock: %d", ret);
1768 return ret;
1769 }
1770
1771 broke_lock = true;
1772 goto again;
1773}
1774
1775static void rbd_object_map_unlock(struct rbd_device *rbd_dev)
1776{
1777 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1778 CEPH_DEFINE_OID_ONSTACK(oid);
1779 int ret;
1780
1781 rbd_object_map_name(rbd_dev, CEPH_NOSNAP, &oid);
1782
1783 ret = ceph_cls_unlock(osdc, &oid, &rbd_dev->header_oloc, RBD_LOCK_NAME,
1784 "");
1785 if (ret && ret != -ENOENT)
1786 rbd_warn(rbd_dev, "failed to unlock object map: %d", ret);
1787}
1788
1789static int decode_object_map_header(void **p, void *end, u64 *object_map_size)
1790{
1791 u8 struct_v;
1792 u32 struct_len;
1793 u32 header_len;
1794 void *header_end;
1795 int ret;
1796
1797 ceph_decode_32_safe(p, end, header_len, e_inval);
1798 header_end = *p + header_len;
1799
1800 ret = ceph_start_decoding(p, end, 1, "BitVector header", &struct_v,
1801 &struct_len);
1802 if (ret)
1803 return ret;
1804
1805 ceph_decode_64_safe(p, end, *object_map_size, e_inval);
1806
1807 *p = header_end;
1808 return 0;
1809
1810e_inval:
1811 return -EINVAL;
1812}
1813
1814static int __rbd_object_map_load(struct rbd_device *rbd_dev)
1815{
1816 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1817 CEPH_DEFINE_OID_ONSTACK(oid);
1818 struct page **pages;
1819 void *p, *end;
1820 size_t reply_len;
1821 u64 num_objects;
1822 u64 object_map_bytes;
1823 u64 object_map_size;
1824 int num_pages;
1825 int ret;
1826
1827 rbd_assert(!rbd_dev->object_map && !rbd_dev->object_map_size);
1828
1829 num_objects = ceph_get_num_objects(&rbd_dev->layout,
1830 rbd_dev->mapping.size);
1831 object_map_bytes = DIV_ROUND_UP_ULL(num_objects * BITS_PER_OBJ,
1832 BITS_PER_BYTE);
1833 num_pages = calc_pages_for(0, object_map_bytes) + 1;
1834 pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
1835 if (IS_ERR(pages))
1836 return PTR_ERR(pages);
1837
1838 reply_len = num_pages * PAGE_SIZE;
1839 rbd_object_map_name(rbd_dev, rbd_dev->spec->snap_id, &oid);
1840 ret = ceph_osdc_call(osdc, &oid, &rbd_dev->header_oloc,
1841 "rbd", "object_map_load", CEPH_OSD_FLAG_READ,
1842 NULL, 0, pages, &reply_len);
1843 if (ret)
1844 goto out;
1845
1846 p = page_address(pages[0]);
1847 end = p + min(reply_len, (size_t)PAGE_SIZE);
1848 ret = decode_object_map_header(&p, end, &object_map_size);
1849 if (ret)
1850 goto out;
1851
1852 if (object_map_size != num_objects) {
1853 rbd_warn(rbd_dev, "object map size mismatch: %llu vs %llu",
1854 object_map_size, num_objects);
1855 ret = -EINVAL;
1856 goto out;
1857 }
1858
1859 if (offset_in_page(p) + object_map_bytes > reply_len) {
1860 ret = -EINVAL;
1861 goto out;
1862 }
1863
1864 rbd_dev->object_map = kvmalloc(object_map_bytes, GFP_KERNEL);
1865 if (!rbd_dev->object_map) {
1866 ret = -ENOMEM;
1867 goto out;
1868 }
1869
1870 rbd_dev->object_map_size = object_map_size;
1871 ceph_copy_from_page_vector(pages, rbd_dev->object_map,
1872 offset_in_page(p), object_map_bytes);
1873
1874out:
1875 ceph_release_page_vector(pages, num_pages);
1876 return ret;
1877}
1878
1879static void rbd_object_map_free(struct rbd_device *rbd_dev)
1880{
1881 kvfree(rbd_dev->object_map);
1882 rbd_dev->object_map = NULL;
1883 rbd_dev->object_map_size = 0;
1884}
1885
1886static int rbd_object_map_load(struct rbd_device *rbd_dev)
1887{
1888 int ret;
1889
1890 ret = __rbd_object_map_load(rbd_dev);
1891 if (ret)
1892 return ret;
1893
1894 ret = rbd_dev_v2_get_flags(rbd_dev);
1895 if (ret) {
1896 rbd_object_map_free(rbd_dev);
1897 return ret;
1898 }
1899
1900 if (rbd_dev->object_map_flags & RBD_FLAG_OBJECT_MAP_INVALID)
1901 rbd_warn(rbd_dev, "object map is invalid");
1902
1903 return 0;
1904}
1905
1906static int rbd_object_map_open(struct rbd_device *rbd_dev)
1907{
1908 int ret;
1909
1910 ret = rbd_object_map_lock(rbd_dev);
1911 if (ret)
1912 return ret;
1913
1914 ret = rbd_object_map_load(rbd_dev);
1915 if (ret) {
1916 rbd_object_map_unlock(rbd_dev);
1917 return ret;
1918 }
1919
1920 return 0;
1921}
1922
1923static void rbd_object_map_close(struct rbd_device *rbd_dev)
1924{
1925 rbd_object_map_free(rbd_dev);
1926 rbd_object_map_unlock(rbd_dev);
1927}
1928
1929/*
1930 * This function needs snap_id (or more precisely just something to
1931 * distinguish between HEAD and snapshot object maps), new_state and
1932 * current_state that were passed to rbd_object_map_update().
1933 *
1934 * To avoid allocating and stashing a context we piggyback on the OSD
1935 * request. A HEAD update has two ops (assert_locked). For new_state
1936 * and current_state we decode our own object_map_update op, encoded in
1937 * rbd_cls_object_map_update().
1938 */
1939static int rbd_object_map_update_finish(struct rbd_obj_request *obj_req,
1940 struct ceph_osd_request *osd_req)
1941{
1942 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1943 struct ceph_osd_data *osd_data;
1944 u64 objno;
1945 u8 state, new_state, current_state;
1946 bool has_current_state;
1947 void *p;
1948
1949 if (osd_req->r_result)
1950 return osd_req->r_result;
1951
1952 /*
1953 * Nothing to do for a snapshot object map.
1954 */
1955 if (osd_req->r_num_ops == 1)
1956 return 0;
1957
1958 /*
1959 * Update in-memory HEAD object map.
1960 */
1961 rbd_assert(osd_req->r_num_ops == 2);
1962 osd_data = osd_req_op_data(osd_req, 1, cls, request_data);
1963 rbd_assert(osd_data->type == CEPH_OSD_DATA_TYPE_PAGES);
1964
1965 p = page_address(osd_data->pages[0]);
1966 objno = ceph_decode_64(&p);
1967 rbd_assert(objno == obj_req->ex.oe_objno);
1968 rbd_assert(ceph_decode_64(&p) == objno + 1);
1969 new_state = ceph_decode_8(&p);
1970 has_current_state = ceph_decode_8(&p);
1971 if (has_current_state)
1972 current_state = ceph_decode_8(&p);
1973
1974 spin_lock(&rbd_dev->object_map_lock);
1975 state = __rbd_object_map_get(rbd_dev, objno);
1976 if (!has_current_state || current_state == state ||
1977 (current_state == OBJECT_EXISTS && state == OBJECT_EXISTS_CLEAN))
1978 __rbd_object_map_set(rbd_dev, objno, new_state);
1979 spin_unlock(&rbd_dev->object_map_lock);
1980
1981 return 0;
1982}
1983
1984static void rbd_object_map_callback(struct ceph_osd_request *osd_req)
1985{
1986 struct rbd_obj_request *obj_req = osd_req->r_priv;
1987 int result;
1988
1989 dout("%s osd_req %p result %d for obj_req %p\n", __func__, osd_req,
1990 osd_req->r_result, obj_req);
1991
1992 result = rbd_object_map_update_finish(obj_req, osd_req);
1993 rbd_obj_handle_request(obj_req, result);
1994}
1995
1996static bool update_needed(struct rbd_device *rbd_dev, u64 objno, u8 new_state)
1997{
1998 u8 state = rbd_object_map_get(rbd_dev, objno);
1999
2000 if (state == new_state ||
2001 (new_state == OBJECT_PENDING && state == OBJECT_NONEXISTENT) ||
2002 (new_state == OBJECT_NONEXISTENT && state != OBJECT_PENDING))
2003 return false;
2004
2005 return true;
2006}
2007
2008static int rbd_cls_object_map_update(struct ceph_osd_request *req,
2009 int which, u64 objno, u8 new_state,
2010 const u8 *current_state)
2011{
2012 struct page **pages;
2013 void *p, *start;
2014 int ret;
2015
2016 ret = osd_req_op_cls_init(req, which, "rbd", "object_map_update");
2017 if (ret)
2018 return ret;
2019
2020 pages = ceph_alloc_page_vector(1, GFP_NOIO);
2021 if (IS_ERR(pages))
2022 return PTR_ERR(pages);
2023
2024 p = start = page_address(pages[0]);
2025 ceph_encode_64(&p, objno);
2026 ceph_encode_64(&p, objno + 1);
2027 ceph_encode_8(&p, new_state);
2028 if (current_state) {
2029 ceph_encode_8(&p, 1);
2030 ceph_encode_8(&p, *current_state);
2031 } else {
2032 ceph_encode_8(&p, 0);
2033 }
2034
2035 osd_req_op_cls_request_data_pages(req, which, pages, p - start, 0,
2036 false, true);
2037 return 0;
2038}
2039
2040/*
2041 * Return:
2042 * 0 - object map update sent
2043 * 1 - object map update isn't needed
2044 * <0 - error
2045 */
2046static int rbd_object_map_update(struct rbd_obj_request *obj_req, u64 snap_id,
2047 u8 new_state, const u8 *current_state)
2048{
2049 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2050 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2051 struct ceph_osd_request *req;
2052 int num_ops = 1;
2053 int which = 0;
2054 int ret;
2055
2056 if (snap_id == CEPH_NOSNAP) {
2057 if (!update_needed(rbd_dev, obj_req->ex.oe_objno, new_state))
2058 return 1;
2059
2060 num_ops++; /* assert_locked */
2061 }
2062
2063 req = ceph_osdc_alloc_request(osdc, NULL, num_ops, false, GFP_NOIO);
2064 if (!req)
2065 return -ENOMEM;
2066
2067 list_add_tail(&req->r_private_item, &obj_req->osd_reqs);
2068 req->r_callback = rbd_object_map_callback;
2069 req->r_priv = obj_req;
2070
2071 rbd_object_map_name(rbd_dev, snap_id, &req->r_base_oid);
2072 ceph_oloc_copy(&req->r_base_oloc, &rbd_dev->header_oloc);
2073 req->r_flags = CEPH_OSD_FLAG_WRITE;
2074 ktime_get_real_ts64(&req->r_mtime);
2075
2076 if (snap_id == CEPH_NOSNAP) {
2077 /*
2078 * Protect against possible race conditions during lock
2079 * ownership transitions.
2080 */
2081 ret = ceph_cls_assert_locked(req, which++, RBD_LOCK_NAME,
2082 CEPH_CLS_LOCK_EXCLUSIVE, "", "");
2083 if (ret)
2084 return ret;
2085 }
2086
2087 ret = rbd_cls_object_map_update(req, which, obj_req->ex.oe_objno,
2088 new_state, current_state);
2089 if (ret)
2090 return ret;
2091
2092 ret = ceph_osdc_alloc_messages(req, GFP_NOIO);
2093 if (ret)
2094 return ret;
2095
2096 ceph_osdc_start_request(osdc, req, false);
2097 return 0;
2098}
2099
2100static void prune_extents(struct ceph_file_extent *img_extents,
2101 u32 *num_img_extents, u64 overlap)
2102{
2103 u32 cnt = *num_img_extents;
2104
2105 /* drop extents completely beyond the overlap */
2106 while (cnt && img_extents[cnt - 1].fe_off >= overlap)
2107 cnt--;
2108
2109 if (cnt) {
2110 struct ceph_file_extent *ex = &img_extents[cnt - 1];
2111
2112 /* trim final overlapping extent */
2113 if (ex->fe_off + ex->fe_len > overlap)
2114 ex->fe_len = overlap - ex->fe_off;
2115 }
2116
2117 *num_img_extents = cnt;
2118}
2119
2120/*
2121 * Determine the byte range(s) covered by either just the object extent
2122 * or the entire object in the parent image.
2123 */
2124static int rbd_obj_calc_img_extents(struct rbd_obj_request *obj_req,
2125 bool entire)
2126{
2127 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2128 int ret;
2129
2130 if (!rbd_dev->parent_overlap)
2131 return 0;
2132
2133 ret = ceph_extent_to_file(&rbd_dev->layout, obj_req->ex.oe_objno,
2134 entire ? 0 : obj_req->ex.oe_off,
2135 entire ? rbd_dev->layout.object_size :
2136 obj_req->ex.oe_len,
2137 &obj_req->img_extents,
2138 &obj_req->num_img_extents);
2139 if (ret)
2140 return ret;
2141
2142 prune_extents(obj_req->img_extents, &obj_req->num_img_extents,
2143 rbd_dev->parent_overlap);
2144 return 0;
2145}
2146
2147static void rbd_osd_setup_data(struct ceph_osd_request *osd_req, int which)
2148{
2149 struct rbd_obj_request *obj_req = osd_req->r_priv;
2150
2151 switch (obj_req->img_request->data_type) {
2152 case OBJ_REQUEST_BIO:
2153 osd_req_op_extent_osd_data_bio(osd_req, which,
2154 &obj_req->bio_pos,
2155 obj_req->ex.oe_len);
2156 break;
2157 case OBJ_REQUEST_BVECS:
2158 case OBJ_REQUEST_OWN_BVECS:
2159 rbd_assert(obj_req->bvec_pos.iter.bi_size ==
2160 obj_req->ex.oe_len);
2161 rbd_assert(obj_req->bvec_idx == obj_req->bvec_count);
2162 osd_req_op_extent_osd_data_bvec_pos(osd_req, which,
2163 &obj_req->bvec_pos);
2164 break;
2165 default:
2166 BUG();
2167 }
2168}
2169
2170static int rbd_osd_setup_stat(struct ceph_osd_request *osd_req, int which)
2171{
2172 struct page **pages;
2173
2174 /*
2175 * The response data for a STAT call consists of:
2176 * le64 length;
2177 * struct {
2178 * le32 tv_sec;
2179 * le32 tv_nsec;
2180 * } mtime;
2181 */
2182 pages = ceph_alloc_page_vector(1, GFP_NOIO);
2183 if (IS_ERR(pages))
2184 return PTR_ERR(pages);
2185
2186 osd_req_op_init(osd_req, which, CEPH_OSD_OP_STAT, 0);
2187 osd_req_op_raw_data_in_pages(osd_req, which, pages,
2188 8 + sizeof(struct ceph_timespec),
2189 0, false, true);
2190 return 0;
2191}
2192
2193static int rbd_osd_setup_copyup(struct ceph_osd_request *osd_req, int which,
2194 u32 bytes)
2195{
2196 struct rbd_obj_request *obj_req = osd_req->r_priv;
2197 int ret;
2198
2199 ret = osd_req_op_cls_init(osd_req, which, "rbd", "copyup");
2200 if (ret)
2201 return ret;
2202
2203 osd_req_op_cls_request_data_bvecs(osd_req, which, obj_req->copyup_bvecs,
2204 obj_req->copyup_bvec_count, bytes);
2205 return 0;
2206}
2207
2208static int rbd_obj_init_read(struct rbd_obj_request *obj_req)
2209{
2210 obj_req->read_state = RBD_OBJ_READ_START;
2211 return 0;
2212}
2213
2214static void __rbd_osd_setup_write_ops(struct ceph_osd_request *osd_req,
2215 int which)
2216{
2217 struct rbd_obj_request *obj_req = osd_req->r_priv;
2218 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2219 u16 opcode;
2220
2221 if (!use_object_map(rbd_dev) ||
2222 !(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST)) {
2223 osd_req_op_alloc_hint_init(osd_req, which++,
2224 rbd_dev->layout.object_size,
2225 rbd_dev->layout.object_size,
2226 rbd_dev->opts->alloc_hint_flags);
2227 }
2228
2229 if (rbd_obj_is_entire(obj_req))
2230 opcode = CEPH_OSD_OP_WRITEFULL;
2231 else
2232 opcode = CEPH_OSD_OP_WRITE;
2233
2234 osd_req_op_extent_init(osd_req, which, opcode,
2235 obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0);
2236 rbd_osd_setup_data(osd_req, which);
2237}
2238
2239static int rbd_obj_init_write(struct rbd_obj_request *obj_req)
2240{
2241 int ret;
2242
2243 /* reverse map the entire object onto the parent */
2244 ret = rbd_obj_calc_img_extents(obj_req, true);
2245 if (ret)
2246 return ret;
2247
2248 if (rbd_obj_copyup_enabled(obj_req))
2249 obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ENABLED;
2250
2251 obj_req->write_state = RBD_OBJ_WRITE_START;
2252 return 0;
2253}
2254
2255static u16 truncate_or_zero_opcode(struct rbd_obj_request *obj_req)
2256{
2257 return rbd_obj_is_tail(obj_req) ? CEPH_OSD_OP_TRUNCATE :
2258 CEPH_OSD_OP_ZERO;
2259}
2260
2261static void __rbd_osd_setup_discard_ops(struct ceph_osd_request *osd_req,
2262 int which)
2263{
2264 struct rbd_obj_request *obj_req = osd_req->r_priv;
2265
2266 if (rbd_obj_is_entire(obj_req) && !obj_req->num_img_extents) {
2267 rbd_assert(obj_req->flags & RBD_OBJ_FLAG_DELETION);
2268 osd_req_op_init(osd_req, which, CEPH_OSD_OP_DELETE, 0);
2269 } else {
2270 osd_req_op_extent_init(osd_req, which,
2271 truncate_or_zero_opcode(obj_req),
2272 obj_req->ex.oe_off, obj_req->ex.oe_len,
2273 0, 0);
2274 }
2275}
2276
2277static int rbd_obj_init_discard(struct rbd_obj_request *obj_req)
2278{
2279 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2280 u64 off, next_off;
2281 int ret;
2282
2283 /*
2284 * Align the range to alloc_size boundary and punt on discards
2285 * that are too small to free up any space.
2286 *
2287 * alloc_size == object_size && is_tail() is a special case for
2288 * filestore with filestore_punch_hole = false, needed to allow
2289 * truncate (in addition to delete).
2290 */
2291 if (rbd_dev->opts->alloc_size != rbd_dev->layout.object_size ||
2292 !rbd_obj_is_tail(obj_req)) {
2293 off = round_up(obj_req->ex.oe_off, rbd_dev->opts->alloc_size);
2294 next_off = round_down(obj_req->ex.oe_off + obj_req->ex.oe_len,
2295 rbd_dev->opts->alloc_size);
2296 if (off >= next_off)
2297 return 1;
2298
2299 dout("%s %p %llu~%llu -> %llu~%llu\n", __func__,
2300 obj_req, obj_req->ex.oe_off, obj_req->ex.oe_len,
2301 off, next_off - off);
2302 obj_req->ex.oe_off = off;
2303 obj_req->ex.oe_len = next_off - off;
2304 }
2305
2306 /* reverse map the entire object onto the parent */
2307 ret = rbd_obj_calc_img_extents(obj_req, true);
2308 if (ret)
2309 return ret;
2310
2311 obj_req->flags |= RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT;
2312 if (rbd_obj_is_entire(obj_req) && !obj_req->num_img_extents)
2313 obj_req->flags |= RBD_OBJ_FLAG_DELETION;
2314
2315 obj_req->write_state = RBD_OBJ_WRITE_START;
2316 return 0;
2317}
2318
2319static void __rbd_osd_setup_zeroout_ops(struct ceph_osd_request *osd_req,
2320 int which)
2321{
2322 struct rbd_obj_request *obj_req = osd_req->r_priv;
2323 u16 opcode;
2324
2325 if (rbd_obj_is_entire(obj_req)) {
2326 if (obj_req->num_img_extents) {
2327 if (!(obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED))
2328 osd_req_op_init(osd_req, which++,
2329 CEPH_OSD_OP_CREATE, 0);
2330 opcode = CEPH_OSD_OP_TRUNCATE;
2331 } else {
2332 rbd_assert(obj_req->flags & RBD_OBJ_FLAG_DELETION);
2333 osd_req_op_init(osd_req, which++,
2334 CEPH_OSD_OP_DELETE, 0);
2335 opcode = 0;
2336 }
2337 } else {
2338 opcode = truncate_or_zero_opcode(obj_req);
2339 }
2340
2341 if (opcode)
2342 osd_req_op_extent_init(osd_req, which, opcode,
2343 obj_req->ex.oe_off, obj_req->ex.oe_len,
2344 0, 0);
2345}
2346
2347static int rbd_obj_init_zeroout(struct rbd_obj_request *obj_req)
2348{
2349 int ret;
2350
2351 /* reverse map the entire object onto the parent */
2352 ret = rbd_obj_calc_img_extents(obj_req, true);
2353 if (ret)
2354 return ret;
2355
2356 if (rbd_obj_copyup_enabled(obj_req))
2357 obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ENABLED;
2358 if (!obj_req->num_img_extents) {
2359 obj_req->flags |= RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT;
2360 if (rbd_obj_is_entire(obj_req))
2361 obj_req->flags |= RBD_OBJ_FLAG_DELETION;
2362 }
2363
2364 obj_req->write_state = RBD_OBJ_WRITE_START;
2365 return 0;
2366}
2367
2368static int count_write_ops(struct rbd_obj_request *obj_req)
2369{
2370 struct rbd_img_request *img_req = obj_req->img_request;
2371
2372 switch (img_req->op_type) {
2373 case OBJ_OP_WRITE:
2374 if (!use_object_map(img_req->rbd_dev) ||
2375 !(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST))
2376 return 2; /* setallochint + write/writefull */
2377
2378 return 1; /* write/writefull */
2379 case OBJ_OP_DISCARD:
2380 return 1; /* delete/truncate/zero */
2381 case OBJ_OP_ZEROOUT:
2382 if (rbd_obj_is_entire(obj_req) && obj_req->num_img_extents &&
2383 !(obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED))
2384 return 2; /* create + truncate */
2385
2386 return 1; /* delete/truncate/zero */
2387 default:
2388 BUG();
2389 }
2390}
2391
2392static void rbd_osd_setup_write_ops(struct ceph_osd_request *osd_req,
2393 int which)
2394{
2395 struct rbd_obj_request *obj_req = osd_req->r_priv;
2396
2397 switch (obj_req->img_request->op_type) {
2398 case OBJ_OP_WRITE:
2399 __rbd_osd_setup_write_ops(osd_req, which);
2400 break;
2401 case OBJ_OP_DISCARD:
2402 __rbd_osd_setup_discard_ops(osd_req, which);
2403 break;
2404 case OBJ_OP_ZEROOUT:
2405 __rbd_osd_setup_zeroout_ops(osd_req, which);
2406 break;
2407 default:
2408 BUG();
2409 }
2410}
2411
2412/*
2413 * Prune the list of object requests (adjust offset and/or length, drop
2414 * redundant requests). Prepare object request state machines and image
2415 * request state machine for execution.
2416 */
2417static int __rbd_img_fill_request(struct rbd_img_request *img_req)
2418{
2419 struct rbd_obj_request *obj_req, *next_obj_req;
2420 int ret;
2421
2422 for_each_obj_request_safe(img_req, obj_req, next_obj_req) {
2423 switch (img_req->op_type) {
2424 case OBJ_OP_READ:
2425 ret = rbd_obj_init_read(obj_req);
2426 break;
2427 case OBJ_OP_WRITE:
2428 ret = rbd_obj_init_write(obj_req);
2429 break;
2430 case OBJ_OP_DISCARD:
2431 ret = rbd_obj_init_discard(obj_req);
2432 break;
2433 case OBJ_OP_ZEROOUT:
2434 ret = rbd_obj_init_zeroout(obj_req);
2435 break;
2436 default:
2437 BUG();
2438 }
2439 if (ret < 0)
2440 return ret;
2441 if (ret > 0) {
2442 rbd_img_obj_request_del(img_req, obj_req);
2443 continue;
2444 }
2445 }
2446
2447 img_req->state = RBD_IMG_START;
2448 return 0;
2449}
2450
2451union rbd_img_fill_iter {
2452 struct ceph_bio_iter bio_iter;
2453 struct ceph_bvec_iter bvec_iter;
2454};
2455
2456struct rbd_img_fill_ctx {
2457 enum obj_request_type pos_type;
2458 union rbd_img_fill_iter *pos;
2459 union rbd_img_fill_iter iter;
2460 ceph_object_extent_fn_t set_pos_fn;
2461 ceph_object_extent_fn_t count_fn;
2462 ceph_object_extent_fn_t copy_fn;
2463};
2464
2465static struct ceph_object_extent *alloc_object_extent(void *arg)
2466{
2467 struct rbd_img_request *img_req = arg;
2468 struct rbd_obj_request *obj_req;
2469
2470 obj_req = rbd_obj_request_create();
2471 if (!obj_req)
2472 return NULL;
2473
2474 rbd_img_obj_request_add(img_req, obj_req);
2475 return &obj_req->ex;
2476}
2477
2478/*
2479 * While su != os && sc == 1 is technically not fancy (it's the same
2480 * layout as su == os && sc == 1), we can't use the nocopy path for it
2481 * because ->set_pos_fn() should be called only once per object.
2482 * ceph_file_to_extents() invokes action_fn once per stripe unit, so
2483 * treat su != os && sc == 1 as fancy.
2484 */
2485static bool rbd_layout_is_fancy(struct ceph_file_layout *l)
2486{
2487 return l->stripe_unit != l->object_size;
2488}
2489
2490static int rbd_img_fill_request_nocopy(struct rbd_img_request *img_req,
2491 struct ceph_file_extent *img_extents,
2492 u32 num_img_extents,
2493 struct rbd_img_fill_ctx *fctx)
2494{
2495 u32 i;
2496 int ret;
2497
2498 img_req->data_type = fctx->pos_type;
2499
2500 /*
2501 * Create object requests and set each object request's starting
2502 * position in the provided bio (list) or bio_vec array.
2503 */
2504 fctx->iter = *fctx->pos;
2505 for (i = 0; i < num_img_extents; i++) {
2506 ret = ceph_file_to_extents(&img_req->rbd_dev->layout,
2507 img_extents[i].fe_off,
2508 img_extents[i].fe_len,
2509 &img_req->object_extents,
2510 alloc_object_extent, img_req,
2511 fctx->set_pos_fn, &fctx->iter);
2512 if (ret)
2513 return ret;
2514 }
2515
2516 return __rbd_img_fill_request(img_req);
2517}
2518
2519/*
2520 * Map a list of image extents to a list of object extents, create the
2521 * corresponding object requests (normally each to a different object,
2522 * but not always) and add them to @img_req. For each object request,
2523 * set up its data descriptor to point to the corresponding chunk(s) of
2524 * @fctx->pos data buffer.
2525 *
2526 * Because ceph_file_to_extents() will merge adjacent object extents
2527 * together, each object request's data descriptor may point to multiple
2528 * different chunks of @fctx->pos data buffer.
2529 *
2530 * @fctx->pos data buffer is assumed to be large enough.
2531 */
2532static int rbd_img_fill_request(struct rbd_img_request *img_req,
2533 struct ceph_file_extent *img_extents,
2534 u32 num_img_extents,
2535 struct rbd_img_fill_ctx *fctx)
2536{
2537 struct rbd_device *rbd_dev = img_req->rbd_dev;
2538 struct rbd_obj_request *obj_req;
2539 u32 i;
2540 int ret;
2541
2542 if (fctx->pos_type == OBJ_REQUEST_NODATA ||
2543 !rbd_layout_is_fancy(&rbd_dev->layout))
2544 return rbd_img_fill_request_nocopy(img_req, img_extents,
2545 num_img_extents, fctx);
2546
2547 img_req->data_type = OBJ_REQUEST_OWN_BVECS;
2548
2549 /*
2550 * Create object requests and determine ->bvec_count for each object
2551 * request. Note that ->bvec_count sum over all object requests may
2552 * be greater than the number of bio_vecs in the provided bio (list)
2553 * or bio_vec array because when mapped, those bio_vecs can straddle
2554 * stripe unit boundaries.
2555 */
2556 fctx->iter = *fctx->pos;
2557 for (i = 0; i < num_img_extents; i++) {
2558 ret = ceph_file_to_extents(&rbd_dev->layout,
2559 img_extents[i].fe_off,
2560 img_extents[i].fe_len,
2561 &img_req->object_extents,
2562 alloc_object_extent, img_req,
2563 fctx->count_fn, &fctx->iter);
2564 if (ret)
2565 return ret;
2566 }
2567
2568 for_each_obj_request(img_req, obj_req) {
2569 obj_req->bvec_pos.bvecs = kmalloc_array(obj_req->bvec_count,
2570 sizeof(*obj_req->bvec_pos.bvecs),
2571 GFP_NOIO);
2572 if (!obj_req->bvec_pos.bvecs)
2573 return -ENOMEM;
2574 }
2575
2576 /*
2577 * Fill in each object request's private bio_vec array, splitting and
2578 * rearranging the provided bio_vecs in stripe unit chunks as needed.
2579 */
2580 fctx->iter = *fctx->pos;
2581 for (i = 0; i < num_img_extents; i++) {
2582 ret = ceph_iterate_extents(&rbd_dev->layout,
2583 img_extents[i].fe_off,
2584 img_extents[i].fe_len,
2585 &img_req->object_extents,
2586 fctx->copy_fn, &fctx->iter);
2587 if (ret)
2588 return ret;
2589 }
2590
2591 return __rbd_img_fill_request(img_req);
2592}
2593
2594static int rbd_img_fill_nodata(struct rbd_img_request *img_req,
2595 u64 off, u64 len)
2596{
2597 struct ceph_file_extent ex = { off, len };
2598 union rbd_img_fill_iter dummy = {};
2599 struct rbd_img_fill_ctx fctx = {
2600 .pos_type = OBJ_REQUEST_NODATA,
2601 .pos = &dummy,
2602 };
2603
2604 return rbd_img_fill_request(img_req, &ex, 1, &fctx);
2605}
2606
2607static void set_bio_pos(struct ceph_object_extent *ex, u32 bytes, void *arg)
2608{
2609 struct rbd_obj_request *obj_req =
2610 container_of(ex, struct rbd_obj_request, ex);
2611 struct ceph_bio_iter *it = arg;
2612
2613 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
2614 obj_req->bio_pos = *it;
2615 ceph_bio_iter_advance(it, bytes);
2616}
2617
2618static void count_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2619{
2620 struct rbd_obj_request *obj_req =
2621 container_of(ex, struct rbd_obj_request, ex);
2622 struct ceph_bio_iter *it = arg;
2623
2624 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
2625 ceph_bio_iter_advance_step(it, bytes, ({
2626 obj_req->bvec_count++;
2627 }));
2628
2629}
2630
2631static void copy_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2632{
2633 struct rbd_obj_request *obj_req =
2634 container_of(ex, struct rbd_obj_request, ex);
2635 struct ceph_bio_iter *it = arg;
2636
2637 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
2638 ceph_bio_iter_advance_step(it, bytes, ({
2639 obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv;
2640 obj_req->bvec_pos.iter.bi_size += bv.bv_len;
2641 }));
2642}
2643
2644static int __rbd_img_fill_from_bio(struct rbd_img_request *img_req,
2645 struct ceph_file_extent *img_extents,
2646 u32 num_img_extents,
2647 struct ceph_bio_iter *bio_pos)
2648{
2649 struct rbd_img_fill_ctx fctx = {
2650 .pos_type = OBJ_REQUEST_BIO,
2651 .pos = (union rbd_img_fill_iter *)bio_pos,
2652 .set_pos_fn = set_bio_pos,
2653 .count_fn = count_bio_bvecs,
2654 .copy_fn = copy_bio_bvecs,
2655 };
2656
2657 return rbd_img_fill_request(img_req, img_extents, num_img_extents,
2658 &fctx);
2659}
2660
2661static int rbd_img_fill_from_bio(struct rbd_img_request *img_req,
2662 u64 off, u64 len, struct bio *bio)
2663{
2664 struct ceph_file_extent ex = { off, len };
2665 struct ceph_bio_iter it = { .bio = bio, .iter = bio->bi_iter };
2666
2667 return __rbd_img_fill_from_bio(img_req, &ex, 1, &it);
2668}
2669
2670static void set_bvec_pos(struct ceph_object_extent *ex, u32 bytes, void *arg)
2671{
2672 struct rbd_obj_request *obj_req =
2673 container_of(ex, struct rbd_obj_request, ex);
2674 struct ceph_bvec_iter *it = arg;
2675
2676 obj_req->bvec_pos = *it;
2677 ceph_bvec_iter_shorten(&obj_req->bvec_pos, bytes);
2678 ceph_bvec_iter_advance(it, bytes);
2679}
2680
2681static void count_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2682{
2683 struct rbd_obj_request *obj_req =
2684 container_of(ex, struct rbd_obj_request, ex);
2685 struct ceph_bvec_iter *it = arg;
2686
2687 ceph_bvec_iter_advance_step(it, bytes, ({
2688 obj_req->bvec_count++;
2689 }));
2690}
2691
2692static void copy_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2693{
2694 struct rbd_obj_request *obj_req =
2695 container_of(ex, struct rbd_obj_request, ex);
2696 struct ceph_bvec_iter *it = arg;
2697
2698 ceph_bvec_iter_advance_step(it, bytes, ({
2699 obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv;
2700 obj_req->bvec_pos.iter.bi_size += bv.bv_len;
2701 }));
2702}
2703
2704static int __rbd_img_fill_from_bvecs(struct rbd_img_request *img_req,
2705 struct ceph_file_extent *img_extents,
2706 u32 num_img_extents,
2707 struct ceph_bvec_iter *bvec_pos)
2708{
2709 struct rbd_img_fill_ctx fctx = {
2710 .pos_type = OBJ_REQUEST_BVECS,
2711 .pos = (union rbd_img_fill_iter *)bvec_pos,
2712 .set_pos_fn = set_bvec_pos,
2713 .count_fn = count_bvecs,
2714 .copy_fn = copy_bvecs,
2715 };
2716
2717 return rbd_img_fill_request(img_req, img_extents, num_img_extents,
2718 &fctx);
2719}
2720
2721static int rbd_img_fill_from_bvecs(struct rbd_img_request *img_req,
2722 struct ceph_file_extent *img_extents,
2723 u32 num_img_extents,
2724 struct bio_vec *bvecs)
2725{
2726 struct ceph_bvec_iter it = {
2727 .bvecs = bvecs,
2728 .iter = { .bi_size = ceph_file_extents_bytes(img_extents,
2729 num_img_extents) },
2730 };
2731
2732 return __rbd_img_fill_from_bvecs(img_req, img_extents, num_img_extents,
2733 &it);
2734}
2735
2736static void rbd_img_handle_request_work(struct work_struct *work)
2737{
2738 struct rbd_img_request *img_req =
2739 container_of(work, struct rbd_img_request, work);
2740
2741 rbd_img_handle_request(img_req, img_req->work_result);
2742}
2743
2744static void rbd_img_schedule(struct rbd_img_request *img_req, int result)
2745{
2746 INIT_WORK(&img_req->work, rbd_img_handle_request_work);
2747 img_req->work_result = result;
2748 queue_work(rbd_wq, &img_req->work);
2749}
2750
2751static bool rbd_obj_may_exist(struct rbd_obj_request *obj_req)
2752{
2753 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2754
2755 if (rbd_object_map_may_exist(rbd_dev, obj_req->ex.oe_objno)) {
2756 obj_req->flags |= RBD_OBJ_FLAG_MAY_EXIST;
2757 return true;
2758 }
2759
2760 dout("%s %p objno %llu assuming dne\n", __func__, obj_req,
2761 obj_req->ex.oe_objno);
2762 return false;
2763}
2764
2765static int rbd_obj_read_object(struct rbd_obj_request *obj_req)
2766{
2767 struct ceph_osd_request *osd_req;
2768 int ret;
2769
2770 osd_req = __rbd_obj_add_osd_request(obj_req, NULL, 1);
2771 if (IS_ERR(osd_req))
2772 return PTR_ERR(osd_req);
2773
2774 osd_req_op_extent_init(osd_req, 0, CEPH_OSD_OP_READ,
2775 obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0);
2776 rbd_osd_setup_data(osd_req, 0);
2777 rbd_osd_format_read(osd_req);
2778
2779 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
2780 if (ret)
2781 return ret;
2782
2783 rbd_osd_submit(osd_req);
2784 return 0;
2785}
2786
2787static int rbd_obj_read_from_parent(struct rbd_obj_request *obj_req)
2788{
2789 struct rbd_img_request *img_req = obj_req->img_request;
2790 struct rbd_device *parent = img_req->rbd_dev->parent;
2791 struct rbd_img_request *child_img_req;
2792 int ret;
2793
2794 child_img_req = kmem_cache_alloc(rbd_img_request_cache, GFP_NOIO);
2795 if (!child_img_req)
2796 return -ENOMEM;
2797
2798 rbd_img_request_init(child_img_req, parent, OBJ_OP_READ);
2799 __set_bit(IMG_REQ_CHILD, &child_img_req->flags);
2800 child_img_req->obj_request = obj_req;
2801
2802 down_read(&parent->header_rwsem);
2803 rbd_img_capture_header(child_img_req);
2804 up_read(&parent->header_rwsem);
2805
2806 dout("%s child_img_req %p for obj_req %p\n", __func__, child_img_req,
2807 obj_req);
2808
2809 if (!rbd_img_is_write(img_req)) {
2810 switch (img_req->data_type) {
2811 case OBJ_REQUEST_BIO:
2812 ret = __rbd_img_fill_from_bio(child_img_req,
2813 obj_req->img_extents,
2814 obj_req->num_img_extents,
2815 &obj_req->bio_pos);
2816 break;
2817 case OBJ_REQUEST_BVECS:
2818 case OBJ_REQUEST_OWN_BVECS:
2819 ret = __rbd_img_fill_from_bvecs(child_img_req,
2820 obj_req->img_extents,
2821 obj_req->num_img_extents,
2822 &obj_req->bvec_pos);
2823 break;
2824 default:
2825 BUG();
2826 }
2827 } else {
2828 ret = rbd_img_fill_from_bvecs(child_img_req,
2829 obj_req->img_extents,
2830 obj_req->num_img_extents,
2831 obj_req->copyup_bvecs);
2832 }
2833 if (ret) {
2834 rbd_img_request_destroy(child_img_req);
2835 return ret;
2836 }
2837
2838 /* avoid parent chain recursion */
2839 rbd_img_schedule(child_img_req, 0);
2840 return 0;
2841}
2842
2843static bool rbd_obj_advance_read(struct rbd_obj_request *obj_req, int *result)
2844{
2845 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2846 int ret;
2847
2848again:
2849 switch (obj_req->read_state) {
2850 case RBD_OBJ_READ_START:
2851 rbd_assert(!*result);
2852
2853 if (!rbd_obj_may_exist(obj_req)) {
2854 *result = -ENOENT;
2855 obj_req->read_state = RBD_OBJ_READ_OBJECT;
2856 goto again;
2857 }
2858
2859 ret = rbd_obj_read_object(obj_req);
2860 if (ret) {
2861 *result = ret;
2862 return true;
2863 }
2864 obj_req->read_state = RBD_OBJ_READ_OBJECT;
2865 return false;
2866 case RBD_OBJ_READ_OBJECT:
2867 if (*result == -ENOENT && rbd_dev->parent_overlap) {
2868 /* reverse map this object extent onto the parent */
2869 ret = rbd_obj_calc_img_extents(obj_req, false);
2870 if (ret) {
2871 *result = ret;
2872 return true;
2873 }
2874 if (obj_req->num_img_extents) {
2875 ret = rbd_obj_read_from_parent(obj_req);
2876 if (ret) {
2877 *result = ret;
2878 return true;
2879 }
2880 obj_req->read_state = RBD_OBJ_READ_PARENT;
2881 return false;
2882 }
2883 }
2884
2885 /*
2886 * -ENOENT means a hole in the image -- zero-fill the entire
2887 * length of the request. A short read also implies zero-fill
2888 * to the end of the request.
2889 */
2890 if (*result == -ENOENT) {
2891 rbd_obj_zero_range(obj_req, 0, obj_req->ex.oe_len);
2892 *result = 0;
2893 } else if (*result >= 0) {
2894 if (*result < obj_req->ex.oe_len)
2895 rbd_obj_zero_range(obj_req, *result,
2896 obj_req->ex.oe_len - *result);
2897 else
2898 rbd_assert(*result == obj_req->ex.oe_len);
2899 *result = 0;
2900 }
2901 return true;
2902 case RBD_OBJ_READ_PARENT:
2903 /*
2904 * The parent image is read only up to the overlap -- zero-fill
2905 * from the overlap to the end of the request.
2906 */
2907 if (!*result) {
2908 u32 obj_overlap = rbd_obj_img_extents_bytes(obj_req);
2909
2910 if (obj_overlap < obj_req->ex.oe_len)
2911 rbd_obj_zero_range(obj_req, obj_overlap,
2912 obj_req->ex.oe_len - obj_overlap);
2913 }
2914 return true;
2915 default:
2916 BUG();
2917 }
2918}
2919
2920static bool rbd_obj_write_is_noop(struct rbd_obj_request *obj_req)
2921{
2922 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2923
2924 if (rbd_object_map_may_exist(rbd_dev, obj_req->ex.oe_objno))
2925 obj_req->flags |= RBD_OBJ_FLAG_MAY_EXIST;
2926
2927 if (!(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST) &&
2928 (obj_req->flags & RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT)) {
2929 dout("%s %p noop for nonexistent\n", __func__, obj_req);
2930 return true;
2931 }
2932
2933 return false;
2934}
2935
2936/*
2937 * Return:
2938 * 0 - object map update sent
2939 * 1 - object map update isn't needed
2940 * <0 - error
2941 */
2942static int rbd_obj_write_pre_object_map(struct rbd_obj_request *obj_req)
2943{
2944 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2945 u8 new_state;
2946
2947 if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
2948 return 1;
2949
2950 if (obj_req->flags & RBD_OBJ_FLAG_DELETION)
2951 new_state = OBJECT_PENDING;
2952 else
2953 new_state = OBJECT_EXISTS;
2954
2955 return rbd_object_map_update(obj_req, CEPH_NOSNAP, new_state, NULL);
2956}
2957
2958static int rbd_obj_write_object(struct rbd_obj_request *obj_req)
2959{
2960 struct ceph_osd_request *osd_req;
2961 int num_ops = count_write_ops(obj_req);
2962 int which = 0;
2963 int ret;
2964
2965 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED)
2966 num_ops++; /* stat */
2967
2968 osd_req = rbd_obj_add_osd_request(obj_req, num_ops);
2969 if (IS_ERR(osd_req))
2970 return PTR_ERR(osd_req);
2971
2972 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) {
2973 ret = rbd_osd_setup_stat(osd_req, which++);
2974 if (ret)
2975 return ret;
2976 }
2977
2978 rbd_osd_setup_write_ops(osd_req, which);
2979 rbd_osd_format_write(osd_req);
2980
2981 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
2982 if (ret)
2983 return ret;
2984
2985 rbd_osd_submit(osd_req);
2986 return 0;
2987}
2988
2989/*
2990 * copyup_bvecs pages are never highmem pages
2991 */
2992static bool is_zero_bvecs(struct bio_vec *bvecs, u32 bytes)
2993{
2994 struct ceph_bvec_iter it = {
2995 .bvecs = bvecs,
2996 .iter = { .bi_size = bytes },
2997 };
2998
2999 ceph_bvec_iter_advance_step(&it, bytes, ({
3000 if (memchr_inv(page_address(bv.bv_page) + bv.bv_offset, 0,
3001 bv.bv_len))
3002 return false;
3003 }));
3004 return true;
3005}
3006
3007#define MODS_ONLY U32_MAX
3008
3009static int rbd_obj_copyup_empty_snapc(struct rbd_obj_request *obj_req,
3010 u32 bytes)
3011{
3012 struct ceph_osd_request *osd_req;
3013 int ret;
3014
3015 dout("%s obj_req %p bytes %u\n", __func__, obj_req, bytes);
3016 rbd_assert(bytes > 0 && bytes != MODS_ONLY);
3017
3018 osd_req = __rbd_obj_add_osd_request(obj_req, &rbd_empty_snapc, 1);
3019 if (IS_ERR(osd_req))
3020 return PTR_ERR(osd_req);
3021
3022 ret = rbd_osd_setup_copyup(osd_req, 0, bytes);
3023 if (ret)
3024 return ret;
3025
3026 rbd_osd_format_write(osd_req);
3027
3028 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
3029 if (ret)
3030 return ret;
3031
3032 rbd_osd_submit(osd_req);
3033 return 0;
3034}
3035
3036static int rbd_obj_copyup_current_snapc(struct rbd_obj_request *obj_req,
3037 u32 bytes)
3038{
3039 struct ceph_osd_request *osd_req;
3040 int num_ops = count_write_ops(obj_req);
3041 int which = 0;
3042 int ret;
3043
3044 dout("%s obj_req %p bytes %u\n", __func__, obj_req, bytes);
3045
3046 if (bytes != MODS_ONLY)
3047 num_ops++; /* copyup */
3048
3049 osd_req = rbd_obj_add_osd_request(obj_req, num_ops);
3050 if (IS_ERR(osd_req))
3051 return PTR_ERR(osd_req);
3052
3053 if (bytes != MODS_ONLY) {
3054 ret = rbd_osd_setup_copyup(osd_req, which++, bytes);
3055 if (ret)
3056 return ret;
3057 }
3058
3059 rbd_osd_setup_write_ops(osd_req, which);
3060 rbd_osd_format_write(osd_req);
3061
3062 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
3063 if (ret)
3064 return ret;
3065
3066 rbd_osd_submit(osd_req);
3067 return 0;
3068}
3069
3070static int setup_copyup_bvecs(struct rbd_obj_request *obj_req, u64 obj_overlap)
3071{
3072 u32 i;
3073
3074 rbd_assert(!obj_req->copyup_bvecs);
3075 obj_req->copyup_bvec_count = calc_pages_for(0, obj_overlap);
3076 obj_req->copyup_bvecs = kcalloc(obj_req->copyup_bvec_count,
3077 sizeof(*obj_req->copyup_bvecs),
3078 GFP_NOIO);
3079 if (!obj_req->copyup_bvecs)
3080 return -ENOMEM;
3081
3082 for (i = 0; i < obj_req->copyup_bvec_count; i++) {
3083 unsigned int len = min(obj_overlap, (u64)PAGE_SIZE);
3084
3085 obj_req->copyup_bvecs[i].bv_page = alloc_page(GFP_NOIO);
3086 if (!obj_req->copyup_bvecs[i].bv_page)
3087 return -ENOMEM;
3088
3089 obj_req->copyup_bvecs[i].bv_offset = 0;
3090 obj_req->copyup_bvecs[i].bv_len = len;
3091 obj_overlap -= len;
3092 }
3093
3094 rbd_assert(!obj_overlap);
3095 return 0;
3096}
3097
3098/*
3099 * The target object doesn't exist. Read the data for the entire
3100 * target object up to the overlap point (if any) from the parent,
3101 * so we can use it for a copyup.
3102 */
3103static int rbd_obj_copyup_read_parent(struct rbd_obj_request *obj_req)
3104{
3105 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3106 int ret;
3107
3108 rbd_assert(obj_req->num_img_extents);
3109 prune_extents(obj_req->img_extents, &obj_req->num_img_extents,
3110 rbd_dev->parent_overlap);
3111 if (!obj_req->num_img_extents) {
3112 /*
3113 * The overlap has become 0 (most likely because the
3114 * image has been flattened). Re-submit the original write
3115 * request -- pass MODS_ONLY since the copyup isn't needed
3116 * anymore.
3117 */
3118 return rbd_obj_copyup_current_snapc(obj_req, MODS_ONLY);
3119 }
3120
3121 ret = setup_copyup_bvecs(obj_req, rbd_obj_img_extents_bytes(obj_req));
3122 if (ret)
3123 return ret;
3124
3125 return rbd_obj_read_from_parent(obj_req);
3126}
3127
3128static void rbd_obj_copyup_object_maps(struct rbd_obj_request *obj_req)
3129{
3130 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3131 struct ceph_snap_context *snapc = obj_req->img_request->snapc;
3132 u8 new_state;
3133 u32 i;
3134 int ret;
3135
3136 rbd_assert(!obj_req->pending.result && !obj_req->pending.num_pending);
3137
3138 if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
3139 return;
3140
3141 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ZEROS)
3142 return;
3143
3144 for (i = 0; i < snapc->num_snaps; i++) {
3145 if ((rbd_dev->header.features & RBD_FEATURE_FAST_DIFF) &&
3146 i + 1 < snapc->num_snaps)
3147 new_state = OBJECT_EXISTS_CLEAN;
3148 else
3149 new_state = OBJECT_EXISTS;
3150
3151 ret = rbd_object_map_update(obj_req, snapc->snaps[i],
3152 new_state, NULL);
3153 if (ret < 0) {
3154 obj_req->pending.result = ret;
3155 return;
3156 }
3157
3158 rbd_assert(!ret);
3159 obj_req->pending.num_pending++;
3160 }
3161}
3162
3163static void rbd_obj_copyup_write_object(struct rbd_obj_request *obj_req)
3164{
3165 u32 bytes = rbd_obj_img_extents_bytes(obj_req);
3166 int ret;
3167
3168 rbd_assert(!obj_req->pending.result && !obj_req->pending.num_pending);
3169
3170 /*
3171 * Only send non-zero copyup data to save some I/O and network
3172 * bandwidth -- zero copyup data is equivalent to the object not
3173 * existing.
3174 */
3175 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ZEROS)
3176 bytes = 0;
3177
3178 if (obj_req->img_request->snapc->num_snaps && bytes > 0) {
3179 /*
3180 * Send a copyup request with an empty snapshot context to
3181 * deep-copyup the object through all existing snapshots.
3182 * A second request with the current snapshot context will be
3183 * sent for the actual modification.
3184 */
3185 ret = rbd_obj_copyup_empty_snapc(obj_req, bytes);
3186 if (ret) {
3187 obj_req->pending.result = ret;
3188 return;
3189 }
3190
3191 obj_req->pending.num_pending++;
3192 bytes = MODS_ONLY;
3193 }
3194
3195 ret = rbd_obj_copyup_current_snapc(obj_req, bytes);
3196 if (ret) {
3197 obj_req->pending.result = ret;
3198 return;
3199 }
3200
3201 obj_req->pending.num_pending++;
3202}
3203
3204static bool rbd_obj_advance_copyup(struct rbd_obj_request *obj_req, int *result)
3205{
3206 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3207 int ret;
3208
3209again:
3210 switch (obj_req->copyup_state) {
3211 case RBD_OBJ_COPYUP_START:
3212 rbd_assert(!*result);
3213
3214 ret = rbd_obj_copyup_read_parent(obj_req);
3215 if (ret) {
3216 *result = ret;
3217 return true;
3218 }
3219 if (obj_req->num_img_extents)
3220 obj_req->copyup_state = RBD_OBJ_COPYUP_READ_PARENT;
3221 else
3222 obj_req->copyup_state = RBD_OBJ_COPYUP_WRITE_OBJECT;
3223 return false;
3224 case RBD_OBJ_COPYUP_READ_PARENT:
3225 if (*result)
3226 return true;
3227
3228 if (is_zero_bvecs(obj_req->copyup_bvecs,
3229 rbd_obj_img_extents_bytes(obj_req))) {
3230 dout("%s %p detected zeros\n", __func__, obj_req);
3231 obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ZEROS;
3232 }
3233
3234 rbd_obj_copyup_object_maps(obj_req);
3235 if (!obj_req->pending.num_pending) {
3236 *result = obj_req->pending.result;
3237 obj_req->copyup_state = RBD_OBJ_COPYUP_OBJECT_MAPS;
3238 goto again;
3239 }
3240 obj_req->copyup_state = __RBD_OBJ_COPYUP_OBJECT_MAPS;
3241 return false;
3242 case __RBD_OBJ_COPYUP_OBJECT_MAPS:
3243 if (!pending_result_dec(&obj_req->pending, result))
3244 return false;
3245 fallthrough;
3246 case RBD_OBJ_COPYUP_OBJECT_MAPS:
3247 if (*result) {
3248 rbd_warn(rbd_dev, "snap object map update failed: %d",
3249 *result);
3250 return true;
3251 }
3252
3253 rbd_obj_copyup_write_object(obj_req);
3254 if (!obj_req->pending.num_pending) {
3255 *result = obj_req->pending.result;
3256 obj_req->copyup_state = RBD_OBJ_COPYUP_WRITE_OBJECT;
3257 goto again;
3258 }
3259 obj_req->copyup_state = __RBD_OBJ_COPYUP_WRITE_OBJECT;
3260 return false;
3261 case __RBD_OBJ_COPYUP_WRITE_OBJECT:
3262 if (!pending_result_dec(&obj_req->pending, result))
3263 return false;
3264 fallthrough;
3265 case RBD_OBJ_COPYUP_WRITE_OBJECT:
3266 return true;
3267 default:
3268 BUG();
3269 }
3270}
3271
3272/*
3273 * Return:
3274 * 0 - object map update sent
3275 * 1 - object map update isn't needed
3276 * <0 - error
3277 */
3278static int rbd_obj_write_post_object_map(struct rbd_obj_request *obj_req)
3279{
3280 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3281 u8 current_state = OBJECT_PENDING;
3282
3283 if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
3284 return 1;
3285
3286 if (!(obj_req->flags & RBD_OBJ_FLAG_DELETION))
3287 return 1;
3288
3289 return rbd_object_map_update(obj_req, CEPH_NOSNAP, OBJECT_NONEXISTENT,
3290 ¤t_state);
3291}
3292
3293static bool rbd_obj_advance_write(struct rbd_obj_request *obj_req, int *result)
3294{
3295 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3296 int ret;
3297
3298again:
3299 switch (obj_req->write_state) {
3300 case RBD_OBJ_WRITE_START:
3301 rbd_assert(!*result);
3302
3303 if (rbd_obj_write_is_noop(obj_req))
3304 return true;
3305
3306 ret = rbd_obj_write_pre_object_map(obj_req);
3307 if (ret < 0) {
3308 *result = ret;
3309 return true;
3310 }
3311 obj_req->write_state = RBD_OBJ_WRITE_PRE_OBJECT_MAP;
3312 if (ret > 0)
3313 goto again;
3314 return false;
3315 case RBD_OBJ_WRITE_PRE_OBJECT_MAP:
3316 if (*result) {
3317 rbd_warn(rbd_dev, "pre object map update failed: %d",
3318 *result);
3319 return true;
3320 }
3321 ret = rbd_obj_write_object(obj_req);
3322 if (ret) {
3323 *result = ret;
3324 return true;
3325 }
3326 obj_req->write_state = RBD_OBJ_WRITE_OBJECT;
3327 return false;
3328 case RBD_OBJ_WRITE_OBJECT:
3329 if (*result == -ENOENT) {
3330 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) {
3331 *result = 0;
3332 obj_req->copyup_state = RBD_OBJ_COPYUP_START;
3333 obj_req->write_state = __RBD_OBJ_WRITE_COPYUP;
3334 goto again;
3335 }
3336 /*
3337 * On a non-existent object:
3338 * delete - -ENOENT, truncate/zero - 0
3339 */
3340 if (obj_req->flags & RBD_OBJ_FLAG_DELETION)
3341 *result = 0;
3342 }
3343 if (*result)
3344 return true;
3345
3346 obj_req->write_state = RBD_OBJ_WRITE_COPYUP;
3347 goto again;
3348 case __RBD_OBJ_WRITE_COPYUP:
3349 if (!rbd_obj_advance_copyup(obj_req, result))
3350 return false;
3351 fallthrough;
3352 case RBD_OBJ_WRITE_COPYUP:
3353 if (*result) {
3354 rbd_warn(rbd_dev, "copyup failed: %d", *result);
3355 return true;
3356 }
3357 ret = rbd_obj_write_post_object_map(obj_req);
3358 if (ret < 0) {
3359 *result = ret;
3360 return true;
3361 }
3362 obj_req->write_state = RBD_OBJ_WRITE_POST_OBJECT_MAP;
3363 if (ret > 0)
3364 goto again;
3365 return false;
3366 case RBD_OBJ_WRITE_POST_OBJECT_MAP:
3367 if (*result)
3368 rbd_warn(rbd_dev, "post object map update failed: %d",
3369 *result);
3370 return true;
3371 default:
3372 BUG();
3373 }
3374}
3375
3376/*
3377 * Return true if @obj_req is completed.
3378 */
3379static bool __rbd_obj_handle_request(struct rbd_obj_request *obj_req,
3380 int *result)
3381{
3382 struct rbd_img_request *img_req = obj_req->img_request;
3383 struct rbd_device *rbd_dev = img_req->rbd_dev;
3384 bool done;
3385
3386 mutex_lock(&obj_req->state_mutex);
3387 if (!rbd_img_is_write(img_req))
3388 done = rbd_obj_advance_read(obj_req, result);
3389 else
3390 done = rbd_obj_advance_write(obj_req, result);
3391 mutex_unlock(&obj_req->state_mutex);
3392
3393 if (done && *result) {
3394 rbd_assert(*result < 0);
3395 rbd_warn(rbd_dev, "%s at objno %llu %llu~%llu result %d",
3396 obj_op_name(img_req->op_type), obj_req->ex.oe_objno,
3397 obj_req->ex.oe_off, obj_req->ex.oe_len, *result);
3398 }
3399 return done;
3400}
3401
3402/*
3403 * This is open-coded in rbd_img_handle_request() to avoid parent chain
3404 * recursion.
3405 */
3406static void rbd_obj_handle_request(struct rbd_obj_request *obj_req, int result)
3407{
3408 if (__rbd_obj_handle_request(obj_req, &result))
3409 rbd_img_handle_request(obj_req->img_request, result);
3410}
3411
3412static bool need_exclusive_lock(struct rbd_img_request *img_req)
3413{
3414 struct rbd_device *rbd_dev = img_req->rbd_dev;
3415
3416 if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK))
3417 return false;
3418
3419 if (rbd_is_ro(rbd_dev))
3420 return false;
3421
3422 rbd_assert(!test_bit(IMG_REQ_CHILD, &img_req->flags));
3423 if (rbd_dev->opts->lock_on_read ||
3424 (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
3425 return true;
3426
3427 return rbd_img_is_write(img_req);
3428}
3429
3430static bool rbd_lock_add_request(struct rbd_img_request *img_req)
3431{
3432 struct rbd_device *rbd_dev = img_req->rbd_dev;
3433 bool locked;
3434
3435 lockdep_assert_held(&rbd_dev->lock_rwsem);
3436 locked = rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED;
3437 spin_lock(&rbd_dev->lock_lists_lock);
3438 rbd_assert(list_empty(&img_req->lock_item));
3439 if (!locked)
3440 list_add_tail(&img_req->lock_item, &rbd_dev->acquiring_list);
3441 else
3442 list_add_tail(&img_req->lock_item, &rbd_dev->running_list);
3443 spin_unlock(&rbd_dev->lock_lists_lock);
3444 return locked;
3445}
3446
3447static void rbd_lock_del_request(struct rbd_img_request *img_req)
3448{
3449 struct rbd_device *rbd_dev = img_req->rbd_dev;
3450 bool need_wakeup;
3451
3452 lockdep_assert_held(&rbd_dev->lock_rwsem);
3453 spin_lock(&rbd_dev->lock_lists_lock);
3454 rbd_assert(!list_empty(&img_req->lock_item));
3455 list_del_init(&img_req->lock_item);
3456 need_wakeup = (rbd_dev->lock_state == RBD_LOCK_STATE_RELEASING &&
3457 list_empty(&rbd_dev->running_list));
3458 spin_unlock(&rbd_dev->lock_lists_lock);
3459 if (need_wakeup)
3460 complete(&rbd_dev->releasing_wait);
3461}
3462
3463static int rbd_img_exclusive_lock(struct rbd_img_request *img_req)
3464{
3465 struct rbd_device *rbd_dev = img_req->rbd_dev;
3466
3467 if (!need_exclusive_lock(img_req))
3468 return 1;
3469
3470 if (rbd_lock_add_request(img_req))
3471 return 1;
3472
3473 if (rbd_dev->opts->exclusive) {
3474 WARN_ON(1); /* lock got released? */
3475 return -EROFS;
3476 }
3477
3478 /*
3479 * Note the use of mod_delayed_work() in rbd_acquire_lock()
3480 * and cancel_delayed_work() in wake_lock_waiters().
3481 */
3482 dout("%s rbd_dev %p queueing lock_dwork\n", __func__, rbd_dev);
3483 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
3484 return 0;
3485}
3486
3487static void rbd_img_object_requests(struct rbd_img_request *img_req)
3488{
3489 struct rbd_obj_request *obj_req;
3490
3491 rbd_assert(!img_req->pending.result && !img_req->pending.num_pending);
3492
3493 for_each_obj_request(img_req, obj_req) {
3494 int result = 0;
3495
3496 if (__rbd_obj_handle_request(obj_req, &result)) {
3497 if (result) {
3498 img_req->pending.result = result;
3499 return;
3500 }
3501 } else {
3502 img_req->pending.num_pending++;
3503 }
3504 }
3505}
3506
3507static bool rbd_img_advance(struct rbd_img_request *img_req, int *result)
3508{
3509 struct rbd_device *rbd_dev = img_req->rbd_dev;
3510 int ret;
3511
3512again:
3513 switch (img_req->state) {
3514 case RBD_IMG_START:
3515 rbd_assert(!*result);
3516
3517 ret = rbd_img_exclusive_lock(img_req);
3518 if (ret < 0) {
3519 *result = ret;
3520 return true;
3521 }
3522 img_req->state = RBD_IMG_EXCLUSIVE_LOCK;
3523 if (ret > 0)
3524 goto again;
3525 return false;
3526 case RBD_IMG_EXCLUSIVE_LOCK:
3527 if (*result)
3528 return true;
3529
3530 rbd_assert(!need_exclusive_lock(img_req) ||
3531 __rbd_is_lock_owner(rbd_dev));
3532
3533 rbd_img_object_requests(img_req);
3534 if (!img_req->pending.num_pending) {
3535 *result = img_req->pending.result;
3536 img_req->state = RBD_IMG_OBJECT_REQUESTS;
3537 goto again;
3538 }
3539 img_req->state = __RBD_IMG_OBJECT_REQUESTS;
3540 return false;
3541 case __RBD_IMG_OBJECT_REQUESTS:
3542 if (!pending_result_dec(&img_req->pending, result))
3543 return false;
3544 fallthrough;
3545 case RBD_IMG_OBJECT_REQUESTS:
3546 return true;
3547 default:
3548 BUG();
3549 }
3550}
3551
3552/*
3553 * Return true if @img_req is completed.
3554 */
3555static bool __rbd_img_handle_request(struct rbd_img_request *img_req,
3556 int *result)
3557{
3558 struct rbd_device *rbd_dev = img_req->rbd_dev;
3559 bool done;
3560
3561 if (need_exclusive_lock(img_req)) {
3562 down_read(&rbd_dev->lock_rwsem);
3563 mutex_lock(&img_req->state_mutex);
3564 done = rbd_img_advance(img_req, result);
3565 if (done)
3566 rbd_lock_del_request(img_req);
3567 mutex_unlock(&img_req->state_mutex);
3568 up_read(&rbd_dev->lock_rwsem);
3569 } else {
3570 mutex_lock(&img_req->state_mutex);
3571 done = rbd_img_advance(img_req, result);
3572 mutex_unlock(&img_req->state_mutex);
3573 }
3574
3575 if (done && *result) {
3576 rbd_assert(*result < 0);
3577 rbd_warn(rbd_dev, "%s%s result %d",
3578 test_bit(IMG_REQ_CHILD, &img_req->flags) ? "child " : "",
3579 obj_op_name(img_req->op_type), *result);
3580 }
3581 return done;
3582}
3583
3584static void rbd_img_handle_request(struct rbd_img_request *img_req, int result)
3585{
3586again:
3587 if (!__rbd_img_handle_request(img_req, &result))
3588 return;
3589
3590 if (test_bit(IMG_REQ_CHILD, &img_req->flags)) {
3591 struct rbd_obj_request *obj_req = img_req->obj_request;
3592
3593 rbd_img_request_destroy(img_req);
3594 if (__rbd_obj_handle_request(obj_req, &result)) {
3595 img_req = obj_req->img_request;
3596 goto again;
3597 }
3598 } else {
3599 struct request *rq = blk_mq_rq_from_pdu(img_req);
3600
3601 rbd_img_request_destroy(img_req);
3602 blk_mq_end_request(rq, errno_to_blk_status(result));
3603 }
3604}
3605
3606static const struct rbd_client_id rbd_empty_cid;
3607
3608static bool rbd_cid_equal(const struct rbd_client_id *lhs,
3609 const struct rbd_client_id *rhs)
3610{
3611 return lhs->gid == rhs->gid && lhs->handle == rhs->handle;
3612}
3613
3614static struct rbd_client_id rbd_get_cid(struct rbd_device *rbd_dev)
3615{
3616 struct rbd_client_id cid;
3617
3618 mutex_lock(&rbd_dev->watch_mutex);
3619 cid.gid = ceph_client_gid(rbd_dev->rbd_client->client);
3620 cid.handle = rbd_dev->watch_cookie;
3621 mutex_unlock(&rbd_dev->watch_mutex);
3622 return cid;
3623}
3624
3625/*
3626 * lock_rwsem must be held for write
3627 */
3628static void rbd_set_owner_cid(struct rbd_device *rbd_dev,
3629 const struct rbd_client_id *cid)
3630{
3631 dout("%s rbd_dev %p %llu-%llu -> %llu-%llu\n", __func__, rbd_dev,
3632 rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle,
3633 cid->gid, cid->handle);
3634 rbd_dev->owner_cid = *cid; /* struct */
3635}
3636
3637static void format_lock_cookie(struct rbd_device *rbd_dev, char *buf)
3638{
3639 mutex_lock(&rbd_dev->watch_mutex);
3640 sprintf(buf, "%s %llu", RBD_LOCK_COOKIE_PREFIX, rbd_dev->watch_cookie);
3641 mutex_unlock(&rbd_dev->watch_mutex);
3642}
3643
3644static void __rbd_lock(struct rbd_device *rbd_dev, const char *cookie)
3645{
3646 struct rbd_client_id cid = rbd_get_cid(rbd_dev);
3647
3648 rbd_dev->lock_state = RBD_LOCK_STATE_LOCKED;
3649 strcpy(rbd_dev->lock_cookie, cookie);
3650 rbd_set_owner_cid(rbd_dev, &cid);
3651 queue_work(rbd_dev->task_wq, &rbd_dev->acquired_lock_work);
3652}
3653
3654/*
3655 * lock_rwsem must be held for write
3656 */
3657static int rbd_lock(struct rbd_device *rbd_dev)
3658{
3659 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3660 char cookie[32];
3661 int ret;
3662
3663 WARN_ON(__rbd_is_lock_owner(rbd_dev) ||
3664 rbd_dev->lock_cookie[0] != '\0');
3665
3666 format_lock_cookie(rbd_dev, cookie);
3667 ret = ceph_cls_lock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
3668 RBD_LOCK_NAME, CEPH_CLS_LOCK_EXCLUSIVE, cookie,
3669 RBD_LOCK_TAG, "", 0);
3670 if (ret)
3671 return ret;
3672
3673 __rbd_lock(rbd_dev, cookie);
3674 return 0;
3675}
3676
3677/*
3678 * lock_rwsem must be held for write
3679 */
3680static void rbd_unlock(struct rbd_device *rbd_dev)
3681{
3682 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3683 int ret;
3684
3685 WARN_ON(!__rbd_is_lock_owner(rbd_dev) ||
3686 rbd_dev->lock_cookie[0] == '\0');
3687
3688 ret = ceph_cls_unlock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
3689 RBD_LOCK_NAME, rbd_dev->lock_cookie);
3690 if (ret && ret != -ENOENT)
3691 rbd_warn(rbd_dev, "failed to unlock header: %d", ret);
3692
3693 /* treat errors as the image is unlocked */
3694 rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED;
3695 rbd_dev->lock_cookie[0] = '\0';
3696 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
3697 queue_work(rbd_dev->task_wq, &rbd_dev->released_lock_work);
3698}
3699
3700static int __rbd_notify_op_lock(struct rbd_device *rbd_dev,
3701 enum rbd_notify_op notify_op,
3702 struct page ***preply_pages,
3703 size_t *preply_len)
3704{
3705 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3706 struct rbd_client_id cid = rbd_get_cid(rbd_dev);
3707 char buf[4 + 8 + 8 + CEPH_ENCODING_START_BLK_LEN];
3708 int buf_size = sizeof(buf);
3709 void *p = buf;
3710
3711 dout("%s rbd_dev %p notify_op %d\n", __func__, rbd_dev, notify_op);
3712
3713 /* encode *LockPayload NotifyMessage (op + ClientId) */
3714 ceph_start_encoding(&p, 2, 1, buf_size - CEPH_ENCODING_START_BLK_LEN);
3715 ceph_encode_32(&p, notify_op);
3716 ceph_encode_64(&p, cid.gid);
3717 ceph_encode_64(&p, cid.handle);
3718
3719 return ceph_osdc_notify(osdc, &rbd_dev->header_oid,
3720 &rbd_dev->header_oloc, buf, buf_size,
3721 RBD_NOTIFY_TIMEOUT, preply_pages, preply_len);
3722}
3723
3724static void rbd_notify_op_lock(struct rbd_device *rbd_dev,
3725 enum rbd_notify_op notify_op)
3726{
3727 __rbd_notify_op_lock(rbd_dev, notify_op, NULL, NULL);
3728}
3729
3730static void rbd_notify_acquired_lock(struct work_struct *work)
3731{
3732 struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
3733 acquired_lock_work);
3734
3735 rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_ACQUIRED_LOCK);
3736}
3737
3738static void rbd_notify_released_lock(struct work_struct *work)
3739{
3740 struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
3741 released_lock_work);
3742
3743 rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_RELEASED_LOCK);
3744}
3745
3746static int rbd_request_lock(struct rbd_device *rbd_dev)
3747{
3748 struct page **reply_pages;
3749 size_t reply_len;
3750 bool lock_owner_responded = false;
3751 int ret;
3752
3753 dout("%s rbd_dev %p\n", __func__, rbd_dev);
3754
3755 ret = __rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_REQUEST_LOCK,
3756 &reply_pages, &reply_len);
3757 if (ret && ret != -ETIMEDOUT) {
3758 rbd_warn(rbd_dev, "failed to request lock: %d", ret);
3759 goto out;
3760 }
3761
3762 if (reply_len > 0 && reply_len <= PAGE_SIZE) {
3763 void *p = page_address(reply_pages[0]);
3764 void *const end = p + reply_len;
3765 u32 n;
3766
3767 ceph_decode_32_safe(&p, end, n, e_inval); /* num_acks */
3768 while (n--) {
3769 u8 struct_v;
3770 u32 len;
3771
3772 ceph_decode_need(&p, end, 8 + 8, e_inval);
3773 p += 8 + 8; /* skip gid and cookie */
3774
3775 ceph_decode_32_safe(&p, end, len, e_inval);
3776 if (!len)
3777 continue;
3778
3779 if (lock_owner_responded) {
3780 rbd_warn(rbd_dev,
3781 "duplicate lock owners detected");
3782 ret = -EIO;
3783 goto out;
3784 }
3785
3786 lock_owner_responded = true;
3787 ret = ceph_start_decoding(&p, end, 1, "ResponseMessage",
3788 &struct_v, &len);
3789 if (ret) {
3790 rbd_warn(rbd_dev,
3791 "failed to decode ResponseMessage: %d",
3792 ret);
3793 goto e_inval;
3794 }
3795
3796 ret = ceph_decode_32(&p);
3797 }
3798 }
3799
3800 if (!lock_owner_responded) {
3801 rbd_warn(rbd_dev, "no lock owners detected");
3802 ret = -ETIMEDOUT;
3803 }
3804
3805out:
3806 ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len));
3807 return ret;
3808
3809e_inval:
3810 ret = -EINVAL;
3811 goto out;
3812}
3813
3814/*
3815 * Either image request state machine(s) or rbd_add_acquire_lock()
3816 * (i.e. "rbd map").
3817 */
3818static void wake_lock_waiters(struct rbd_device *rbd_dev, int result)
3819{
3820 struct rbd_img_request *img_req;
3821
3822 dout("%s rbd_dev %p result %d\n", __func__, rbd_dev, result);
3823 lockdep_assert_held_write(&rbd_dev->lock_rwsem);
3824
3825 cancel_delayed_work(&rbd_dev->lock_dwork);
3826 if (!completion_done(&rbd_dev->acquire_wait)) {
3827 rbd_assert(list_empty(&rbd_dev->acquiring_list) &&
3828 list_empty(&rbd_dev->running_list));
3829 rbd_dev->acquire_err = result;
3830 complete_all(&rbd_dev->acquire_wait);
3831 return;
3832 }
3833
3834 list_for_each_entry(img_req, &rbd_dev->acquiring_list, lock_item) {
3835 mutex_lock(&img_req->state_mutex);
3836 rbd_assert(img_req->state == RBD_IMG_EXCLUSIVE_LOCK);
3837 rbd_img_schedule(img_req, result);
3838 mutex_unlock(&img_req->state_mutex);
3839 }
3840
3841 list_splice_tail_init(&rbd_dev->acquiring_list, &rbd_dev->running_list);
3842}
3843
3844static int get_lock_owner_info(struct rbd_device *rbd_dev,
3845 struct ceph_locker **lockers, u32 *num_lockers)
3846{
3847 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3848 u8 lock_type;
3849 char *lock_tag;
3850 int ret;
3851
3852 dout("%s rbd_dev %p\n", __func__, rbd_dev);
3853
3854 ret = ceph_cls_lock_info(osdc, &rbd_dev->header_oid,
3855 &rbd_dev->header_oloc, RBD_LOCK_NAME,
3856 &lock_type, &lock_tag, lockers, num_lockers);
3857 if (ret)
3858 return ret;
3859
3860 if (*num_lockers == 0) {
3861 dout("%s rbd_dev %p no lockers detected\n", __func__, rbd_dev);
3862 goto out;
3863 }
3864
3865 if (strcmp(lock_tag, RBD_LOCK_TAG)) {
3866 rbd_warn(rbd_dev, "locked by external mechanism, tag %s",
3867 lock_tag);
3868 ret = -EBUSY;
3869 goto out;
3870 }
3871
3872 if (lock_type == CEPH_CLS_LOCK_SHARED) {
3873 rbd_warn(rbd_dev, "shared lock type detected");
3874 ret = -EBUSY;
3875 goto out;
3876 }
3877
3878 if (strncmp((*lockers)[0].id.cookie, RBD_LOCK_COOKIE_PREFIX,
3879 strlen(RBD_LOCK_COOKIE_PREFIX))) {
3880 rbd_warn(rbd_dev, "locked by external mechanism, cookie %s",
3881 (*lockers)[0].id.cookie);
3882 ret = -EBUSY;
3883 goto out;
3884 }
3885
3886out:
3887 kfree(lock_tag);
3888 return ret;
3889}
3890
3891static int find_watcher(struct rbd_device *rbd_dev,
3892 const struct ceph_locker *locker)
3893{
3894 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3895 struct ceph_watch_item *watchers;
3896 u32 num_watchers;
3897 u64 cookie;
3898 int i;
3899 int ret;
3900
3901 ret = ceph_osdc_list_watchers(osdc, &rbd_dev->header_oid,
3902 &rbd_dev->header_oloc, &watchers,
3903 &num_watchers);
3904 if (ret)
3905 return ret;
3906
3907 sscanf(locker->id.cookie, RBD_LOCK_COOKIE_PREFIX " %llu", &cookie);
3908 for (i = 0; i < num_watchers; i++) {
3909 /*
3910 * Ignore addr->type while comparing. This mimics
3911 * entity_addr_t::get_legacy_str() + strcmp().
3912 */
3913 if (ceph_addr_equal_no_type(&watchers[i].addr,
3914 &locker->info.addr) &&
3915 watchers[i].cookie == cookie) {
3916 struct rbd_client_id cid = {
3917 .gid = le64_to_cpu(watchers[i].name.num),
3918 .handle = cookie,
3919 };
3920
3921 dout("%s rbd_dev %p found cid %llu-%llu\n", __func__,
3922 rbd_dev, cid.gid, cid.handle);
3923 rbd_set_owner_cid(rbd_dev, &cid);
3924 ret = 1;
3925 goto out;
3926 }
3927 }
3928
3929 dout("%s rbd_dev %p no watchers\n", __func__, rbd_dev);
3930 ret = 0;
3931out:
3932 kfree(watchers);
3933 return ret;
3934}
3935
3936/*
3937 * lock_rwsem must be held for write
3938 */
3939static int rbd_try_lock(struct rbd_device *rbd_dev)
3940{
3941 struct ceph_client *client = rbd_dev->rbd_client->client;
3942 struct ceph_locker *lockers;
3943 u32 num_lockers;
3944 int ret;
3945
3946 for (;;) {
3947 ret = rbd_lock(rbd_dev);
3948 if (ret != -EBUSY)
3949 return ret;
3950
3951 /* determine if the current lock holder is still alive */
3952 ret = get_lock_owner_info(rbd_dev, &lockers, &num_lockers);
3953 if (ret)
3954 return ret;
3955
3956 if (num_lockers == 0)
3957 goto again;
3958
3959 ret = find_watcher(rbd_dev, lockers);
3960 if (ret)
3961 goto out; /* request lock or error */
3962
3963 rbd_warn(rbd_dev, "breaking header lock owned by %s%llu",
3964 ENTITY_NAME(lockers[0].id.name));
3965
3966 ret = ceph_monc_blocklist_add(&client->monc,
3967 &lockers[0].info.addr);
3968 if (ret) {
3969 rbd_warn(rbd_dev, "blocklist of %s%llu failed: %d",
3970 ENTITY_NAME(lockers[0].id.name), ret);
3971 goto out;
3972 }
3973
3974 ret = ceph_cls_break_lock(&client->osdc, &rbd_dev->header_oid,
3975 &rbd_dev->header_oloc, RBD_LOCK_NAME,
3976 lockers[0].id.cookie,
3977 &lockers[0].id.name);
3978 if (ret && ret != -ENOENT)
3979 goto out;
3980
3981again:
3982 ceph_free_lockers(lockers, num_lockers);
3983 }
3984
3985out:
3986 ceph_free_lockers(lockers, num_lockers);
3987 return ret;
3988}
3989
3990static int rbd_post_acquire_action(struct rbd_device *rbd_dev)
3991{
3992 int ret;
3993
3994 if (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP) {
3995 ret = rbd_object_map_open(rbd_dev);
3996 if (ret)
3997 return ret;
3998 }
3999
4000 return 0;
4001}
4002
4003/*
4004 * Return:
4005 * 0 - lock acquired
4006 * 1 - caller should call rbd_request_lock()
4007 * <0 - error
4008 */
4009static int rbd_try_acquire_lock(struct rbd_device *rbd_dev)
4010{
4011 int ret;
4012
4013 down_read(&rbd_dev->lock_rwsem);
4014 dout("%s rbd_dev %p read lock_state %d\n", __func__, rbd_dev,
4015 rbd_dev->lock_state);
4016 if (__rbd_is_lock_owner(rbd_dev)) {
4017 up_read(&rbd_dev->lock_rwsem);
4018 return 0;
4019 }
4020
4021 up_read(&rbd_dev->lock_rwsem);
4022 down_write(&rbd_dev->lock_rwsem);
4023 dout("%s rbd_dev %p write lock_state %d\n", __func__, rbd_dev,
4024 rbd_dev->lock_state);
4025 if (__rbd_is_lock_owner(rbd_dev)) {
4026 up_write(&rbd_dev->lock_rwsem);
4027 return 0;
4028 }
4029
4030 ret = rbd_try_lock(rbd_dev);
4031 if (ret < 0) {
4032 rbd_warn(rbd_dev, "failed to lock header: %d", ret);
4033 if (ret == -EBLOCKLISTED)
4034 goto out;
4035
4036 ret = 1; /* request lock anyway */
4037 }
4038 if (ret > 0) {
4039 up_write(&rbd_dev->lock_rwsem);
4040 return ret;
4041 }
4042
4043 rbd_assert(rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED);
4044 rbd_assert(list_empty(&rbd_dev->running_list));
4045
4046 ret = rbd_post_acquire_action(rbd_dev);
4047 if (ret) {
4048 rbd_warn(rbd_dev, "post-acquire action failed: %d", ret);
4049 /*
4050 * Can't stay in RBD_LOCK_STATE_LOCKED because
4051 * rbd_lock_add_request() would let the request through,
4052 * assuming that e.g. object map is locked and loaded.
4053 */
4054 rbd_unlock(rbd_dev);
4055 }
4056
4057out:
4058 wake_lock_waiters(rbd_dev, ret);
4059 up_write(&rbd_dev->lock_rwsem);
4060 return ret;
4061}
4062
4063static void rbd_acquire_lock(struct work_struct *work)
4064{
4065 struct rbd_device *rbd_dev = container_of(to_delayed_work(work),
4066 struct rbd_device, lock_dwork);
4067 int ret;
4068
4069 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4070again:
4071 ret = rbd_try_acquire_lock(rbd_dev);
4072 if (ret <= 0) {
4073 dout("%s rbd_dev %p ret %d - done\n", __func__, rbd_dev, ret);
4074 return;
4075 }
4076
4077 ret = rbd_request_lock(rbd_dev);
4078 if (ret == -ETIMEDOUT) {
4079 goto again; /* treat this as a dead client */
4080 } else if (ret == -EROFS) {
4081 rbd_warn(rbd_dev, "peer will not release lock");
4082 down_write(&rbd_dev->lock_rwsem);
4083 wake_lock_waiters(rbd_dev, ret);
4084 up_write(&rbd_dev->lock_rwsem);
4085 } else if (ret < 0) {
4086 rbd_warn(rbd_dev, "error requesting lock: %d", ret);
4087 mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
4088 RBD_RETRY_DELAY);
4089 } else {
4090 /*
4091 * lock owner acked, but resend if we don't see them
4092 * release the lock
4093 */
4094 dout("%s rbd_dev %p requeuing lock_dwork\n", __func__,
4095 rbd_dev);
4096 mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
4097 msecs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT * MSEC_PER_SEC));
4098 }
4099}
4100
4101static bool rbd_quiesce_lock(struct rbd_device *rbd_dev)
4102{
4103 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4104 lockdep_assert_held_write(&rbd_dev->lock_rwsem);
4105
4106 if (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED)
4107 return false;
4108
4109 /*
4110 * Ensure that all in-flight IO is flushed.
4111 */
4112 rbd_dev->lock_state = RBD_LOCK_STATE_RELEASING;
4113 rbd_assert(!completion_done(&rbd_dev->releasing_wait));
4114 if (list_empty(&rbd_dev->running_list))
4115 return true;
4116
4117 up_write(&rbd_dev->lock_rwsem);
4118 wait_for_completion(&rbd_dev->releasing_wait);
4119
4120 down_write(&rbd_dev->lock_rwsem);
4121 if (rbd_dev->lock_state != RBD_LOCK_STATE_RELEASING)
4122 return false;
4123
4124 rbd_assert(list_empty(&rbd_dev->running_list));
4125 return true;
4126}
4127
4128static void rbd_pre_release_action(struct rbd_device *rbd_dev)
4129{
4130 if (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP)
4131 rbd_object_map_close(rbd_dev);
4132}
4133
4134static void __rbd_release_lock(struct rbd_device *rbd_dev)
4135{
4136 rbd_assert(list_empty(&rbd_dev->running_list));
4137
4138 rbd_pre_release_action(rbd_dev);
4139 rbd_unlock(rbd_dev);
4140}
4141
4142/*
4143 * lock_rwsem must be held for write
4144 */
4145static void rbd_release_lock(struct rbd_device *rbd_dev)
4146{
4147 if (!rbd_quiesce_lock(rbd_dev))
4148 return;
4149
4150 __rbd_release_lock(rbd_dev);
4151
4152 /*
4153 * Give others a chance to grab the lock - we would re-acquire
4154 * almost immediately if we got new IO while draining the running
4155 * list otherwise. We need to ack our own notifications, so this
4156 * lock_dwork will be requeued from rbd_handle_released_lock() by
4157 * way of maybe_kick_acquire().
4158 */
4159 cancel_delayed_work(&rbd_dev->lock_dwork);
4160}
4161
4162static void rbd_release_lock_work(struct work_struct *work)
4163{
4164 struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
4165 unlock_work);
4166
4167 down_write(&rbd_dev->lock_rwsem);
4168 rbd_release_lock(rbd_dev);
4169 up_write(&rbd_dev->lock_rwsem);
4170}
4171
4172static void maybe_kick_acquire(struct rbd_device *rbd_dev)
4173{
4174 bool have_requests;
4175
4176 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4177 if (__rbd_is_lock_owner(rbd_dev))
4178 return;
4179
4180 spin_lock(&rbd_dev->lock_lists_lock);
4181 have_requests = !list_empty(&rbd_dev->acquiring_list);
4182 spin_unlock(&rbd_dev->lock_lists_lock);
4183 if (have_requests || delayed_work_pending(&rbd_dev->lock_dwork)) {
4184 dout("%s rbd_dev %p kicking lock_dwork\n", __func__, rbd_dev);
4185 mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
4186 }
4187}
4188
4189static void rbd_handle_acquired_lock(struct rbd_device *rbd_dev, u8 struct_v,
4190 void **p)
4191{
4192 struct rbd_client_id cid = { 0 };
4193
4194 if (struct_v >= 2) {
4195 cid.gid = ceph_decode_64(p);
4196 cid.handle = ceph_decode_64(p);
4197 }
4198
4199 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
4200 cid.handle);
4201 if (!rbd_cid_equal(&cid, &rbd_empty_cid)) {
4202 down_write(&rbd_dev->lock_rwsem);
4203 if (rbd_cid_equal(&cid, &rbd_dev->owner_cid)) {
4204 dout("%s rbd_dev %p cid %llu-%llu == owner_cid\n",
4205 __func__, rbd_dev, cid.gid, cid.handle);
4206 } else {
4207 rbd_set_owner_cid(rbd_dev, &cid);
4208 }
4209 downgrade_write(&rbd_dev->lock_rwsem);
4210 } else {
4211 down_read(&rbd_dev->lock_rwsem);
4212 }
4213
4214 maybe_kick_acquire(rbd_dev);
4215 up_read(&rbd_dev->lock_rwsem);
4216}
4217
4218static void rbd_handle_released_lock(struct rbd_device *rbd_dev, u8 struct_v,
4219 void **p)
4220{
4221 struct rbd_client_id cid = { 0 };
4222
4223 if (struct_v >= 2) {
4224 cid.gid = ceph_decode_64(p);
4225 cid.handle = ceph_decode_64(p);
4226 }
4227
4228 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
4229 cid.handle);
4230 if (!rbd_cid_equal(&cid, &rbd_empty_cid)) {
4231 down_write(&rbd_dev->lock_rwsem);
4232 if (!rbd_cid_equal(&cid, &rbd_dev->owner_cid)) {
4233 dout("%s rbd_dev %p cid %llu-%llu != owner_cid %llu-%llu\n",
4234 __func__, rbd_dev, cid.gid, cid.handle,
4235 rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle);
4236 } else {
4237 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
4238 }
4239 downgrade_write(&rbd_dev->lock_rwsem);
4240 } else {
4241 down_read(&rbd_dev->lock_rwsem);
4242 }
4243
4244 maybe_kick_acquire(rbd_dev);
4245 up_read(&rbd_dev->lock_rwsem);
4246}
4247
4248/*
4249 * Returns result for ResponseMessage to be encoded (<= 0), or 1 if no
4250 * ResponseMessage is needed.
4251 */
4252static int rbd_handle_request_lock(struct rbd_device *rbd_dev, u8 struct_v,
4253 void **p)
4254{
4255 struct rbd_client_id my_cid = rbd_get_cid(rbd_dev);
4256 struct rbd_client_id cid = { 0 };
4257 int result = 1;
4258
4259 if (struct_v >= 2) {
4260 cid.gid = ceph_decode_64(p);
4261 cid.handle = ceph_decode_64(p);
4262 }
4263
4264 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
4265 cid.handle);
4266 if (rbd_cid_equal(&cid, &my_cid))
4267 return result;
4268
4269 down_read(&rbd_dev->lock_rwsem);
4270 if (__rbd_is_lock_owner(rbd_dev)) {
4271 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED &&
4272 rbd_cid_equal(&rbd_dev->owner_cid, &rbd_empty_cid))
4273 goto out_unlock;
4274
4275 /*
4276 * encode ResponseMessage(0) so the peer can detect
4277 * a missing owner
4278 */
4279 result = 0;
4280
4281 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED) {
4282 if (!rbd_dev->opts->exclusive) {
4283 dout("%s rbd_dev %p queueing unlock_work\n",
4284 __func__, rbd_dev);
4285 queue_work(rbd_dev->task_wq,
4286 &rbd_dev->unlock_work);
4287 } else {
4288 /* refuse to release the lock */
4289 result = -EROFS;
4290 }
4291 }
4292 }
4293
4294out_unlock:
4295 up_read(&rbd_dev->lock_rwsem);
4296 return result;
4297}
4298
4299static void __rbd_acknowledge_notify(struct rbd_device *rbd_dev,
4300 u64 notify_id, u64 cookie, s32 *result)
4301{
4302 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4303 char buf[4 + CEPH_ENCODING_START_BLK_LEN];
4304 int buf_size = sizeof(buf);
4305 int ret;
4306
4307 if (result) {
4308 void *p = buf;
4309
4310 /* encode ResponseMessage */
4311 ceph_start_encoding(&p, 1, 1,
4312 buf_size - CEPH_ENCODING_START_BLK_LEN);
4313 ceph_encode_32(&p, *result);
4314 } else {
4315 buf_size = 0;
4316 }
4317
4318 ret = ceph_osdc_notify_ack(osdc, &rbd_dev->header_oid,
4319 &rbd_dev->header_oloc, notify_id, cookie,
4320 buf, buf_size);
4321 if (ret)
4322 rbd_warn(rbd_dev, "acknowledge_notify failed: %d", ret);
4323}
4324
4325static void rbd_acknowledge_notify(struct rbd_device *rbd_dev, u64 notify_id,
4326 u64 cookie)
4327{
4328 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4329 __rbd_acknowledge_notify(rbd_dev, notify_id, cookie, NULL);
4330}
4331
4332static void rbd_acknowledge_notify_result(struct rbd_device *rbd_dev,
4333 u64 notify_id, u64 cookie, s32 result)
4334{
4335 dout("%s rbd_dev %p result %d\n", __func__, rbd_dev, result);
4336 __rbd_acknowledge_notify(rbd_dev, notify_id, cookie, &result);
4337}
4338
4339static void rbd_watch_cb(void *arg, u64 notify_id, u64 cookie,
4340 u64 notifier_id, void *data, size_t data_len)
4341{
4342 struct rbd_device *rbd_dev = arg;
4343 void *p = data;
4344 void *const end = p + data_len;
4345 u8 struct_v = 0;
4346 u32 len;
4347 u32 notify_op;
4348 int ret;
4349
4350 dout("%s rbd_dev %p cookie %llu notify_id %llu data_len %zu\n",
4351 __func__, rbd_dev, cookie, notify_id, data_len);
4352 if (data_len) {
4353 ret = ceph_start_decoding(&p, end, 1, "NotifyMessage",
4354 &struct_v, &len);
4355 if (ret) {
4356 rbd_warn(rbd_dev, "failed to decode NotifyMessage: %d",
4357 ret);
4358 return;
4359 }
4360
4361 notify_op = ceph_decode_32(&p);
4362 } else {
4363 /* legacy notification for header updates */
4364 notify_op = RBD_NOTIFY_OP_HEADER_UPDATE;
4365 len = 0;
4366 }
4367
4368 dout("%s rbd_dev %p notify_op %u\n", __func__, rbd_dev, notify_op);
4369 switch (notify_op) {
4370 case RBD_NOTIFY_OP_ACQUIRED_LOCK:
4371 rbd_handle_acquired_lock(rbd_dev, struct_v, &p);
4372 rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4373 break;
4374 case RBD_NOTIFY_OP_RELEASED_LOCK:
4375 rbd_handle_released_lock(rbd_dev, struct_v, &p);
4376 rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4377 break;
4378 case RBD_NOTIFY_OP_REQUEST_LOCK:
4379 ret = rbd_handle_request_lock(rbd_dev, struct_v, &p);
4380 if (ret <= 0)
4381 rbd_acknowledge_notify_result(rbd_dev, notify_id,
4382 cookie, ret);
4383 else
4384 rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4385 break;
4386 case RBD_NOTIFY_OP_HEADER_UPDATE:
4387 ret = rbd_dev_refresh(rbd_dev);
4388 if (ret)
4389 rbd_warn(rbd_dev, "refresh failed: %d", ret);
4390
4391 rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4392 break;
4393 default:
4394 if (rbd_is_lock_owner(rbd_dev))
4395 rbd_acknowledge_notify_result(rbd_dev, notify_id,
4396 cookie, -EOPNOTSUPP);
4397 else
4398 rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4399 break;
4400 }
4401}
4402
4403static void __rbd_unregister_watch(struct rbd_device *rbd_dev);
4404
4405static void rbd_watch_errcb(void *arg, u64 cookie, int err)
4406{
4407 struct rbd_device *rbd_dev = arg;
4408
4409 rbd_warn(rbd_dev, "encountered watch error: %d", err);
4410
4411 down_write(&rbd_dev->lock_rwsem);
4412 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
4413 up_write(&rbd_dev->lock_rwsem);
4414
4415 mutex_lock(&rbd_dev->watch_mutex);
4416 if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED) {
4417 __rbd_unregister_watch(rbd_dev);
4418 rbd_dev->watch_state = RBD_WATCH_STATE_ERROR;
4419
4420 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->watch_dwork, 0);
4421 }
4422 mutex_unlock(&rbd_dev->watch_mutex);
4423}
4424
4425/*
4426 * watch_mutex must be locked
4427 */
4428static int __rbd_register_watch(struct rbd_device *rbd_dev)
4429{
4430 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4431 struct ceph_osd_linger_request *handle;
4432
4433 rbd_assert(!rbd_dev->watch_handle);
4434 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4435
4436 handle = ceph_osdc_watch(osdc, &rbd_dev->header_oid,
4437 &rbd_dev->header_oloc, rbd_watch_cb,
4438 rbd_watch_errcb, rbd_dev);
4439 if (IS_ERR(handle))
4440 return PTR_ERR(handle);
4441
4442 rbd_dev->watch_handle = handle;
4443 return 0;
4444}
4445
4446/*
4447 * watch_mutex must be locked
4448 */
4449static void __rbd_unregister_watch(struct rbd_device *rbd_dev)
4450{
4451 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4452 int ret;
4453
4454 rbd_assert(rbd_dev->watch_handle);
4455 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4456
4457 ret = ceph_osdc_unwatch(osdc, rbd_dev->watch_handle);
4458 if (ret)
4459 rbd_warn(rbd_dev, "failed to unwatch: %d", ret);
4460
4461 rbd_dev->watch_handle = NULL;
4462}
4463
4464static int rbd_register_watch(struct rbd_device *rbd_dev)
4465{
4466 int ret;
4467
4468 mutex_lock(&rbd_dev->watch_mutex);
4469 rbd_assert(rbd_dev->watch_state == RBD_WATCH_STATE_UNREGISTERED);
4470 ret = __rbd_register_watch(rbd_dev);
4471 if (ret)
4472 goto out;
4473
4474 rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED;
4475 rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id;
4476
4477out:
4478 mutex_unlock(&rbd_dev->watch_mutex);
4479 return ret;
4480}
4481
4482static void cancel_tasks_sync(struct rbd_device *rbd_dev)
4483{
4484 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4485
4486 cancel_work_sync(&rbd_dev->acquired_lock_work);
4487 cancel_work_sync(&rbd_dev->released_lock_work);
4488 cancel_delayed_work_sync(&rbd_dev->lock_dwork);
4489 cancel_work_sync(&rbd_dev->unlock_work);
4490}
4491
4492/*
4493 * header_rwsem must not be held to avoid a deadlock with
4494 * rbd_dev_refresh() when flushing notifies.
4495 */
4496static void rbd_unregister_watch(struct rbd_device *rbd_dev)
4497{
4498 cancel_tasks_sync(rbd_dev);
4499
4500 mutex_lock(&rbd_dev->watch_mutex);
4501 if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED)
4502 __rbd_unregister_watch(rbd_dev);
4503 rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED;
4504 mutex_unlock(&rbd_dev->watch_mutex);
4505
4506 cancel_delayed_work_sync(&rbd_dev->watch_dwork);
4507 ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc);
4508}
4509
4510/*
4511 * lock_rwsem must be held for write
4512 */
4513static void rbd_reacquire_lock(struct rbd_device *rbd_dev)
4514{
4515 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4516 char cookie[32];
4517 int ret;
4518
4519 if (!rbd_quiesce_lock(rbd_dev))
4520 return;
4521
4522 format_lock_cookie(rbd_dev, cookie);
4523 ret = ceph_cls_set_cookie(osdc, &rbd_dev->header_oid,
4524 &rbd_dev->header_oloc, RBD_LOCK_NAME,
4525 CEPH_CLS_LOCK_EXCLUSIVE, rbd_dev->lock_cookie,
4526 RBD_LOCK_TAG, cookie);
4527 if (ret) {
4528 if (ret != -EOPNOTSUPP)
4529 rbd_warn(rbd_dev, "failed to update lock cookie: %d",
4530 ret);
4531
4532 /*
4533 * Lock cookie cannot be updated on older OSDs, so do
4534 * a manual release and queue an acquire.
4535 */
4536 __rbd_release_lock(rbd_dev);
4537 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
4538 } else {
4539 __rbd_lock(rbd_dev, cookie);
4540 wake_lock_waiters(rbd_dev, 0);
4541 }
4542}
4543
4544static void rbd_reregister_watch(struct work_struct *work)
4545{
4546 struct rbd_device *rbd_dev = container_of(to_delayed_work(work),
4547 struct rbd_device, watch_dwork);
4548 int ret;
4549
4550 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4551
4552 mutex_lock(&rbd_dev->watch_mutex);
4553 if (rbd_dev->watch_state != RBD_WATCH_STATE_ERROR) {
4554 mutex_unlock(&rbd_dev->watch_mutex);
4555 return;
4556 }
4557
4558 ret = __rbd_register_watch(rbd_dev);
4559 if (ret) {
4560 rbd_warn(rbd_dev, "failed to reregister watch: %d", ret);
4561 if (ret != -EBLOCKLISTED && ret != -ENOENT) {
4562 queue_delayed_work(rbd_dev->task_wq,
4563 &rbd_dev->watch_dwork,
4564 RBD_RETRY_DELAY);
4565 mutex_unlock(&rbd_dev->watch_mutex);
4566 return;
4567 }
4568
4569 mutex_unlock(&rbd_dev->watch_mutex);
4570 down_write(&rbd_dev->lock_rwsem);
4571 wake_lock_waiters(rbd_dev, ret);
4572 up_write(&rbd_dev->lock_rwsem);
4573 return;
4574 }
4575
4576 rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED;
4577 rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id;
4578 mutex_unlock(&rbd_dev->watch_mutex);
4579
4580 down_write(&rbd_dev->lock_rwsem);
4581 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED)
4582 rbd_reacquire_lock(rbd_dev);
4583 up_write(&rbd_dev->lock_rwsem);
4584
4585 ret = rbd_dev_refresh(rbd_dev);
4586 if (ret)
4587 rbd_warn(rbd_dev, "reregistration refresh failed: %d", ret);
4588}
4589
4590/*
4591 * Synchronous osd object method call. Returns the number of bytes
4592 * returned in the outbound buffer, or a negative error code.
4593 */
4594static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
4595 struct ceph_object_id *oid,
4596 struct ceph_object_locator *oloc,
4597 const char *method_name,
4598 const void *outbound,
4599 size_t outbound_size,
4600 void *inbound,
4601 size_t inbound_size)
4602{
4603 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4604 struct page *req_page = NULL;
4605 struct page *reply_page;
4606 int ret;
4607
4608 /*
4609 * Method calls are ultimately read operations. The result
4610 * should placed into the inbound buffer provided. They
4611 * also supply outbound data--parameters for the object
4612 * method. Currently if this is present it will be a
4613 * snapshot id.
4614 */
4615 if (outbound) {
4616 if (outbound_size > PAGE_SIZE)
4617 return -E2BIG;
4618
4619 req_page = alloc_page(GFP_KERNEL);
4620 if (!req_page)
4621 return -ENOMEM;
4622
4623 memcpy(page_address(req_page), outbound, outbound_size);
4624 }
4625
4626 reply_page = alloc_page(GFP_KERNEL);
4627 if (!reply_page) {
4628 if (req_page)
4629 __free_page(req_page);
4630 return -ENOMEM;
4631 }
4632
4633 ret = ceph_osdc_call(osdc, oid, oloc, RBD_DRV_NAME, method_name,
4634 CEPH_OSD_FLAG_READ, req_page, outbound_size,
4635 &reply_page, &inbound_size);
4636 if (!ret) {
4637 memcpy(inbound, page_address(reply_page), inbound_size);
4638 ret = inbound_size;
4639 }
4640
4641 if (req_page)
4642 __free_page(req_page);
4643 __free_page(reply_page);
4644 return ret;
4645}
4646
4647static void rbd_queue_workfn(struct work_struct *work)
4648{
4649 struct rbd_img_request *img_request =
4650 container_of(work, struct rbd_img_request, work);
4651 struct rbd_device *rbd_dev = img_request->rbd_dev;
4652 enum obj_operation_type op_type = img_request->op_type;
4653 struct request *rq = blk_mq_rq_from_pdu(img_request);
4654 u64 offset = (u64)blk_rq_pos(rq) << SECTOR_SHIFT;
4655 u64 length = blk_rq_bytes(rq);
4656 u64 mapping_size;
4657 int result;
4658
4659 /* Ignore/skip any zero-length requests */
4660 if (!length) {
4661 dout("%s: zero-length request\n", __func__);
4662 result = 0;
4663 goto err_img_request;
4664 }
4665
4666 blk_mq_start_request(rq);
4667
4668 down_read(&rbd_dev->header_rwsem);
4669 mapping_size = rbd_dev->mapping.size;
4670 rbd_img_capture_header(img_request);
4671 up_read(&rbd_dev->header_rwsem);
4672
4673 if (offset + length > mapping_size) {
4674 rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)", offset,
4675 length, mapping_size);
4676 result = -EIO;
4677 goto err_img_request;
4678 }
4679
4680 dout("%s rbd_dev %p img_req %p %s %llu~%llu\n", __func__, rbd_dev,
4681 img_request, obj_op_name(op_type), offset, length);
4682
4683 if (op_type == OBJ_OP_DISCARD || op_type == OBJ_OP_ZEROOUT)
4684 result = rbd_img_fill_nodata(img_request, offset, length);
4685 else
4686 result = rbd_img_fill_from_bio(img_request, offset, length,
4687 rq->bio);
4688 if (result)
4689 goto err_img_request;
4690
4691 rbd_img_handle_request(img_request, 0);
4692 return;
4693
4694err_img_request:
4695 rbd_img_request_destroy(img_request);
4696 if (result)
4697 rbd_warn(rbd_dev, "%s %llx at %llx result %d",
4698 obj_op_name(op_type), length, offset, result);
4699 blk_mq_end_request(rq, errno_to_blk_status(result));
4700}
4701
4702static blk_status_t rbd_queue_rq(struct blk_mq_hw_ctx *hctx,
4703 const struct blk_mq_queue_data *bd)
4704{
4705 struct rbd_device *rbd_dev = hctx->queue->queuedata;
4706 struct rbd_img_request *img_req = blk_mq_rq_to_pdu(bd->rq);
4707 enum obj_operation_type op_type;
4708
4709 switch (req_op(bd->rq)) {
4710 case REQ_OP_DISCARD:
4711 op_type = OBJ_OP_DISCARD;
4712 break;
4713 case REQ_OP_WRITE_ZEROES:
4714 op_type = OBJ_OP_ZEROOUT;
4715 break;
4716 case REQ_OP_WRITE:
4717 op_type = OBJ_OP_WRITE;
4718 break;
4719 case REQ_OP_READ:
4720 op_type = OBJ_OP_READ;
4721 break;
4722 default:
4723 rbd_warn(rbd_dev, "unknown req_op %d", req_op(bd->rq));
4724 return BLK_STS_IOERR;
4725 }
4726
4727 rbd_img_request_init(img_req, rbd_dev, op_type);
4728
4729 if (rbd_img_is_write(img_req)) {
4730 if (rbd_is_ro(rbd_dev)) {
4731 rbd_warn(rbd_dev, "%s on read-only mapping",
4732 obj_op_name(img_req->op_type));
4733 return BLK_STS_IOERR;
4734 }
4735 rbd_assert(!rbd_is_snap(rbd_dev));
4736 }
4737
4738 INIT_WORK(&img_req->work, rbd_queue_workfn);
4739 queue_work(rbd_wq, &img_req->work);
4740 return BLK_STS_OK;
4741}
4742
4743static void rbd_free_disk(struct rbd_device *rbd_dev)
4744{
4745 blk_cleanup_disk(rbd_dev->disk);
4746 blk_mq_free_tag_set(&rbd_dev->tag_set);
4747 rbd_dev->disk = NULL;
4748}
4749
4750static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
4751 struct ceph_object_id *oid,
4752 struct ceph_object_locator *oloc,
4753 void *buf, int buf_len)
4754
4755{
4756 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4757 struct ceph_osd_request *req;
4758 struct page **pages;
4759 int num_pages = calc_pages_for(0, buf_len);
4760 int ret;
4761
4762 req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_KERNEL);
4763 if (!req)
4764 return -ENOMEM;
4765
4766 ceph_oid_copy(&req->r_base_oid, oid);
4767 ceph_oloc_copy(&req->r_base_oloc, oloc);
4768 req->r_flags = CEPH_OSD_FLAG_READ;
4769
4770 pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
4771 if (IS_ERR(pages)) {
4772 ret = PTR_ERR(pages);
4773 goto out_req;
4774 }
4775
4776 osd_req_op_extent_init(req, 0, CEPH_OSD_OP_READ, 0, buf_len, 0, 0);
4777 osd_req_op_extent_osd_data_pages(req, 0, pages, buf_len, 0, false,
4778 true);
4779
4780 ret = ceph_osdc_alloc_messages(req, GFP_KERNEL);
4781 if (ret)
4782 goto out_req;
4783
4784 ceph_osdc_start_request(osdc, req, false);
4785 ret = ceph_osdc_wait_request(osdc, req);
4786 if (ret >= 0)
4787 ceph_copy_from_page_vector(pages, buf, 0, ret);
4788
4789out_req:
4790 ceph_osdc_put_request(req);
4791 return ret;
4792}
4793
4794/*
4795 * Read the complete header for the given rbd device. On successful
4796 * return, the rbd_dev->header field will contain up-to-date
4797 * information about the image.
4798 */
4799static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
4800{
4801 struct rbd_image_header_ondisk *ondisk = NULL;
4802 u32 snap_count = 0;
4803 u64 names_size = 0;
4804 u32 want_count;
4805 int ret;
4806
4807 /*
4808 * The complete header will include an array of its 64-bit
4809 * snapshot ids, followed by the names of those snapshots as
4810 * a contiguous block of NUL-terminated strings. Note that
4811 * the number of snapshots could change by the time we read
4812 * it in, in which case we re-read it.
4813 */
4814 do {
4815 size_t size;
4816
4817 kfree(ondisk);
4818
4819 size = sizeof (*ondisk);
4820 size += snap_count * sizeof (struct rbd_image_snap_ondisk);
4821 size += names_size;
4822 ondisk = kmalloc(size, GFP_KERNEL);
4823 if (!ondisk)
4824 return -ENOMEM;
4825
4826 ret = rbd_obj_read_sync(rbd_dev, &rbd_dev->header_oid,
4827 &rbd_dev->header_oloc, ondisk, size);
4828 if (ret < 0)
4829 goto out;
4830 if ((size_t)ret < size) {
4831 ret = -ENXIO;
4832 rbd_warn(rbd_dev, "short header read (want %zd got %d)",
4833 size, ret);
4834 goto out;
4835 }
4836 if (!rbd_dev_ondisk_valid(ondisk)) {
4837 ret = -ENXIO;
4838 rbd_warn(rbd_dev, "invalid header");
4839 goto out;
4840 }
4841
4842 names_size = le64_to_cpu(ondisk->snap_names_len);
4843 want_count = snap_count;
4844 snap_count = le32_to_cpu(ondisk->snap_count);
4845 } while (snap_count != want_count);
4846
4847 ret = rbd_header_from_disk(rbd_dev, ondisk);
4848out:
4849 kfree(ondisk);
4850
4851 return ret;
4852}
4853
4854static void rbd_dev_update_size(struct rbd_device *rbd_dev)
4855{
4856 sector_t size;
4857
4858 /*
4859 * If EXISTS is not set, rbd_dev->disk may be NULL, so don't
4860 * try to update its size. If REMOVING is set, updating size
4861 * is just useless work since the device can't be opened.
4862 */
4863 if (test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags) &&
4864 !test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) {
4865 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
4866 dout("setting size to %llu sectors", (unsigned long long)size);
4867 set_capacity_and_notify(rbd_dev->disk, size);
4868 }
4869}
4870
4871static int rbd_dev_refresh(struct rbd_device *rbd_dev)
4872{
4873 u64 mapping_size;
4874 int ret;
4875
4876 down_write(&rbd_dev->header_rwsem);
4877 mapping_size = rbd_dev->mapping.size;
4878
4879 ret = rbd_dev_header_info(rbd_dev);
4880 if (ret)
4881 goto out;
4882
4883 /*
4884 * If there is a parent, see if it has disappeared due to the
4885 * mapped image getting flattened.
4886 */
4887 if (rbd_dev->parent) {
4888 ret = rbd_dev_v2_parent_info(rbd_dev);
4889 if (ret)
4890 goto out;
4891 }
4892
4893 rbd_assert(!rbd_is_snap(rbd_dev));
4894 rbd_dev->mapping.size = rbd_dev->header.image_size;
4895
4896out:
4897 up_write(&rbd_dev->header_rwsem);
4898 if (!ret && mapping_size != rbd_dev->mapping.size)
4899 rbd_dev_update_size(rbd_dev);
4900
4901 return ret;
4902}
4903
4904static const struct blk_mq_ops rbd_mq_ops = {
4905 .queue_rq = rbd_queue_rq,
4906};
4907
4908static int rbd_init_disk(struct rbd_device *rbd_dev)
4909{
4910 struct gendisk *disk;
4911 struct request_queue *q;
4912 unsigned int objset_bytes =
4913 rbd_dev->layout.object_size * rbd_dev->layout.stripe_count;
4914 int err;
4915
4916 memset(&rbd_dev->tag_set, 0, sizeof(rbd_dev->tag_set));
4917 rbd_dev->tag_set.ops = &rbd_mq_ops;
4918 rbd_dev->tag_set.queue_depth = rbd_dev->opts->queue_depth;
4919 rbd_dev->tag_set.numa_node = NUMA_NO_NODE;
4920 rbd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
4921 rbd_dev->tag_set.nr_hw_queues = num_present_cpus();
4922 rbd_dev->tag_set.cmd_size = sizeof(struct rbd_img_request);
4923
4924 err = blk_mq_alloc_tag_set(&rbd_dev->tag_set);
4925 if (err)
4926 return err;
4927
4928 disk = blk_mq_alloc_disk(&rbd_dev->tag_set, rbd_dev);
4929 if (IS_ERR(disk)) {
4930 err = PTR_ERR(disk);
4931 goto out_tag_set;
4932 }
4933 q = disk->queue;
4934
4935 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
4936 rbd_dev->dev_id);
4937 disk->major = rbd_dev->major;
4938 disk->first_minor = rbd_dev->minor;
4939 if (single_major) {
4940 disk->minors = (1 << RBD_SINGLE_MAJOR_PART_SHIFT);
4941 disk->flags |= GENHD_FL_EXT_DEVT;
4942 } else {
4943 disk->minors = RBD_MINORS_PER_MAJOR;
4944 }
4945 disk->fops = &rbd_bd_ops;
4946 disk->private_data = rbd_dev;
4947
4948 blk_queue_flag_set(QUEUE_FLAG_NONROT, q);
4949 /* QUEUE_FLAG_ADD_RANDOM is off by default for blk-mq */
4950
4951 blk_queue_max_hw_sectors(q, objset_bytes >> SECTOR_SHIFT);
4952 q->limits.max_sectors = queue_max_hw_sectors(q);
4953 blk_queue_max_segments(q, USHRT_MAX);
4954 blk_queue_max_segment_size(q, UINT_MAX);
4955 blk_queue_io_min(q, rbd_dev->opts->alloc_size);
4956 blk_queue_io_opt(q, rbd_dev->opts->alloc_size);
4957
4958 if (rbd_dev->opts->trim) {
4959 blk_queue_flag_set(QUEUE_FLAG_DISCARD, q);
4960 q->limits.discard_granularity = rbd_dev->opts->alloc_size;
4961 blk_queue_max_discard_sectors(q, objset_bytes >> SECTOR_SHIFT);
4962 blk_queue_max_write_zeroes_sectors(q, objset_bytes >> SECTOR_SHIFT);
4963 }
4964
4965 if (!ceph_test_opt(rbd_dev->rbd_client->client, NOCRC))
4966 blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, q);
4967
4968 rbd_dev->disk = disk;
4969
4970 return 0;
4971out_tag_set:
4972 blk_mq_free_tag_set(&rbd_dev->tag_set);
4973 return err;
4974}
4975
4976/*
4977 sysfs
4978*/
4979
4980static struct rbd_device *dev_to_rbd_dev(struct device *dev)
4981{
4982 return container_of(dev, struct rbd_device, dev);
4983}
4984
4985static ssize_t rbd_size_show(struct device *dev,
4986 struct device_attribute *attr, char *buf)
4987{
4988 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4989
4990 return sprintf(buf, "%llu\n",
4991 (unsigned long long)rbd_dev->mapping.size);
4992}
4993
4994static ssize_t rbd_features_show(struct device *dev,
4995 struct device_attribute *attr, char *buf)
4996{
4997 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4998
4999 return sprintf(buf, "0x%016llx\n", rbd_dev->header.features);
5000}
5001
5002static ssize_t rbd_major_show(struct device *dev,
5003 struct device_attribute *attr, char *buf)
5004{
5005 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5006
5007 if (rbd_dev->major)
5008 return sprintf(buf, "%d\n", rbd_dev->major);
5009
5010 return sprintf(buf, "(none)\n");
5011}
5012
5013static ssize_t rbd_minor_show(struct device *dev,
5014 struct device_attribute *attr, char *buf)
5015{
5016 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5017
5018 return sprintf(buf, "%d\n", rbd_dev->minor);
5019}
5020
5021static ssize_t rbd_client_addr_show(struct device *dev,
5022 struct device_attribute *attr, char *buf)
5023{
5024 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5025 struct ceph_entity_addr *client_addr =
5026 ceph_client_addr(rbd_dev->rbd_client->client);
5027
5028 return sprintf(buf, "%pISpc/%u\n", &client_addr->in_addr,
5029 le32_to_cpu(client_addr->nonce));
5030}
5031
5032static ssize_t rbd_client_id_show(struct device *dev,
5033 struct device_attribute *attr, char *buf)
5034{
5035 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5036
5037 return sprintf(buf, "client%lld\n",
5038 ceph_client_gid(rbd_dev->rbd_client->client));
5039}
5040
5041static ssize_t rbd_cluster_fsid_show(struct device *dev,
5042 struct device_attribute *attr, char *buf)
5043{
5044 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5045
5046 return sprintf(buf, "%pU\n", &rbd_dev->rbd_client->client->fsid);
5047}
5048
5049static ssize_t rbd_config_info_show(struct device *dev,
5050 struct device_attribute *attr, char *buf)
5051{
5052 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5053
5054 if (!capable(CAP_SYS_ADMIN))
5055 return -EPERM;
5056
5057 return sprintf(buf, "%s\n", rbd_dev->config_info);
5058}
5059
5060static ssize_t rbd_pool_show(struct device *dev,
5061 struct device_attribute *attr, char *buf)
5062{
5063 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5064
5065 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
5066}
5067
5068static ssize_t rbd_pool_id_show(struct device *dev,
5069 struct device_attribute *attr, char *buf)
5070{
5071 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5072
5073 return sprintf(buf, "%llu\n",
5074 (unsigned long long) rbd_dev->spec->pool_id);
5075}
5076
5077static ssize_t rbd_pool_ns_show(struct device *dev,
5078 struct device_attribute *attr, char *buf)
5079{
5080 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5081
5082 return sprintf(buf, "%s\n", rbd_dev->spec->pool_ns ?: "");
5083}
5084
5085static ssize_t rbd_name_show(struct device *dev,
5086 struct device_attribute *attr, char *buf)
5087{
5088 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5089
5090 if (rbd_dev->spec->image_name)
5091 return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
5092
5093 return sprintf(buf, "(unknown)\n");
5094}
5095
5096static ssize_t rbd_image_id_show(struct device *dev,
5097 struct device_attribute *attr, char *buf)
5098{
5099 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5100
5101 return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
5102}
5103
5104/*
5105 * Shows the name of the currently-mapped snapshot (or
5106 * RBD_SNAP_HEAD_NAME for the base image).
5107 */
5108static ssize_t rbd_snap_show(struct device *dev,
5109 struct device_attribute *attr,
5110 char *buf)
5111{
5112 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5113
5114 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
5115}
5116
5117static ssize_t rbd_snap_id_show(struct device *dev,
5118 struct device_attribute *attr, char *buf)
5119{
5120 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5121
5122 return sprintf(buf, "%llu\n", rbd_dev->spec->snap_id);
5123}
5124
5125/*
5126 * For a v2 image, shows the chain of parent images, separated by empty
5127 * lines. For v1 images or if there is no parent, shows "(no parent
5128 * image)".
5129 */
5130static ssize_t rbd_parent_show(struct device *dev,
5131 struct device_attribute *attr,
5132 char *buf)
5133{
5134 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5135 ssize_t count = 0;
5136
5137 if (!rbd_dev->parent)
5138 return sprintf(buf, "(no parent image)\n");
5139
5140 for ( ; rbd_dev->parent; rbd_dev = rbd_dev->parent) {
5141 struct rbd_spec *spec = rbd_dev->parent_spec;
5142
5143 count += sprintf(&buf[count], "%s"
5144 "pool_id %llu\npool_name %s\n"
5145 "pool_ns %s\n"
5146 "image_id %s\nimage_name %s\n"
5147 "snap_id %llu\nsnap_name %s\n"
5148 "overlap %llu\n",
5149 !count ? "" : "\n", /* first? */
5150 spec->pool_id, spec->pool_name,
5151 spec->pool_ns ?: "",
5152 spec->image_id, spec->image_name ?: "(unknown)",
5153 spec->snap_id, spec->snap_name,
5154 rbd_dev->parent_overlap);
5155 }
5156
5157 return count;
5158}
5159
5160static ssize_t rbd_image_refresh(struct device *dev,
5161 struct device_attribute *attr,
5162 const char *buf,
5163 size_t size)
5164{
5165 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5166 int ret;
5167
5168 if (!capable(CAP_SYS_ADMIN))
5169 return -EPERM;
5170
5171 ret = rbd_dev_refresh(rbd_dev);
5172 if (ret)
5173 return ret;
5174
5175 return size;
5176}
5177
5178static DEVICE_ATTR(size, 0444, rbd_size_show, NULL);
5179static DEVICE_ATTR(features, 0444, rbd_features_show, NULL);
5180static DEVICE_ATTR(major, 0444, rbd_major_show, NULL);
5181static DEVICE_ATTR(minor, 0444, rbd_minor_show, NULL);
5182static DEVICE_ATTR(client_addr, 0444, rbd_client_addr_show, NULL);
5183static DEVICE_ATTR(client_id, 0444, rbd_client_id_show, NULL);
5184static DEVICE_ATTR(cluster_fsid, 0444, rbd_cluster_fsid_show, NULL);
5185static DEVICE_ATTR(config_info, 0400, rbd_config_info_show, NULL);
5186static DEVICE_ATTR(pool, 0444, rbd_pool_show, NULL);
5187static DEVICE_ATTR(pool_id, 0444, rbd_pool_id_show, NULL);
5188static DEVICE_ATTR(pool_ns, 0444, rbd_pool_ns_show, NULL);
5189static DEVICE_ATTR(name, 0444, rbd_name_show, NULL);
5190static DEVICE_ATTR(image_id, 0444, rbd_image_id_show, NULL);
5191static DEVICE_ATTR(refresh, 0200, NULL, rbd_image_refresh);
5192static DEVICE_ATTR(current_snap, 0444, rbd_snap_show, NULL);
5193static DEVICE_ATTR(snap_id, 0444, rbd_snap_id_show, NULL);
5194static DEVICE_ATTR(parent, 0444, rbd_parent_show, NULL);
5195
5196static struct attribute *rbd_attrs[] = {
5197 &dev_attr_size.attr,
5198 &dev_attr_features.attr,
5199 &dev_attr_major.attr,
5200 &dev_attr_minor.attr,
5201 &dev_attr_client_addr.attr,
5202 &dev_attr_client_id.attr,
5203 &dev_attr_cluster_fsid.attr,
5204 &dev_attr_config_info.attr,
5205 &dev_attr_pool.attr,
5206 &dev_attr_pool_id.attr,
5207 &dev_attr_pool_ns.attr,
5208 &dev_attr_name.attr,
5209 &dev_attr_image_id.attr,
5210 &dev_attr_current_snap.attr,
5211 &dev_attr_snap_id.attr,
5212 &dev_attr_parent.attr,
5213 &dev_attr_refresh.attr,
5214 NULL
5215};
5216
5217static struct attribute_group rbd_attr_group = {
5218 .attrs = rbd_attrs,
5219};
5220
5221static const struct attribute_group *rbd_attr_groups[] = {
5222 &rbd_attr_group,
5223 NULL
5224};
5225
5226static void rbd_dev_release(struct device *dev);
5227
5228static const struct device_type rbd_device_type = {
5229 .name = "rbd",
5230 .groups = rbd_attr_groups,
5231 .release = rbd_dev_release,
5232};
5233
5234static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
5235{
5236 kref_get(&spec->kref);
5237
5238 return spec;
5239}
5240
5241static void rbd_spec_free(struct kref *kref);
5242static void rbd_spec_put(struct rbd_spec *spec)
5243{
5244 if (spec)
5245 kref_put(&spec->kref, rbd_spec_free);
5246}
5247
5248static struct rbd_spec *rbd_spec_alloc(void)
5249{
5250 struct rbd_spec *spec;
5251
5252 spec = kzalloc(sizeof (*spec), GFP_KERNEL);
5253 if (!spec)
5254 return NULL;
5255
5256 spec->pool_id = CEPH_NOPOOL;
5257 spec->snap_id = CEPH_NOSNAP;
5258 kref_init(&spec->kref);
5259
5260 return spec;
5261}
5262
5263static void rbd_spec_free(struct kref *kref)
5264{
5265 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
5266
5267 kfree(spec->pool_name);
5268 kfree(spec->pool_ns);
5269 kfree(spec->image_id);
5270 kfree(spec->image_name);
5271 kfree(spec->snap_name);
5272 kfree(spec);
5273}
5274
5275static void rbd_dev_free(struct rbd_device *rbd_dev)
5276{
5277 WARN_ON(rbd_dev->watch_state != RBD_WATCH_STATE_UNREGISTERED);
5278 WARN_ON(rbd_dev->lock_state != RBD_LOCK_STATE_UNLOCKED);
5279
5280 ceph_oid_destroy(&rbd_dev->header_oid);
5281 ceph_oloc_destroy(&rbd_dev->header_oloc);
5282 kfree(rbd_dev->config_info);
5283
5284 rbd_put_client(rbd_dev->rbd_client);
5285 rbd_spec_put(rbd_dev->spec);
5286 kfree(rbd_dev->opts);
5287 kfree(rbd_dev);
5288}
5289
5290static void rbd_dev_release(struct device *dev)
5291{
5292 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5293 bool need_put = !!rbd_dev->opts;
5294
5295 if (need_put) {
5296 destroy_workqueue(rbd_dev->task_wq);
5297 ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id);
5298 }
5299
5300 rbd_dev_free(rbd_dev);
5301
5302 /*
5303 * This is racy, but way better than putting module outside of
5304 * the release callback. The race window is pretty small, so
5305 * doing something similar to dm (dm-builtin.c) is overkill.
5306 */
5307 if (need_put)
5308 module_put(THIS_MODULE);
5309}
5310
5311static struct rbd_device *__rbd_dev_create(struct rbd_client *rbdc,
5312 struct rbd_spec *spec)
5313{
5314 struct rbd_device *rbd_dev;
5315
5316 rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL);
5317 if (!rbd_dev)
5318 return NULL;
5319
5320 spin_lock_init(&rbd_dev->lock);
5321 INIT_LIST_HEAD(&rbd_dev->node);
5322 init_rwsem(&rbd_dev->header_rwsem);
5323
5324 rbd_dev->header.data_pool_id = CEPH_NOPOOL;
5325 ceph_oid_init(&rbd_dev->header_oid);
5326 rbd_dev->header_oloc.pool = spec->pool_id;
5327 if (spec->pool_ns) {
5328 WARN_ON(!*spec->pool_ns);
5329 rbd_dev->header_oloc.pool_ns =
5330 ceph_find_or_create_string(spec->pool_ns,
5331 strlen(spec->pool_ns));
5332 }
5333
5334 mutex_init(&rbd_dev->watch_mutex);
5335 rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED;
5336 INIT_DELAYED_WORK(&rbd_dev->watch_dwork, rbd_reregister_watch);
5337
5338 init_rwsem(&rbd_dev->lock_rwsem);
5339 rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED;
5340 INIT_WORK(&rbd_dev->acquired_lock_work, rbd_notify_acquired_lock);
5341 INIT_WORK(&rbd_dev->released_lock_work, rbd_notify_released_lock);
5342 INIT_DELAYED_WORK(&rbd_dev->lock_dwork, rbd_acquire_lock);
5343 INIT_WORK(&rbd_dev->unlock_work, rbd_release_lock_work);
5344 spin_lock_init(&rbd_dev->lock_lists_lock);
5345 INIT_LIST_HEAD(&rbd_dev->acquiring_list);
5346 INIT_LIST_HEAD(&rbd_dev->running_list);
5347 init_completion(&rbd_dev->acquire_wait);
5348 init_completion(&rbd_dev->releasing_wait);
5349
5350 spin_lock_init(&rbd_dev->object_map_lock);
5351
5352 rbd_dev->dev.bus = &rbd_bus_type;
5353 rbd_dev->dev.type = &rbd_device_type;
5354 rbd_dev->dev.parent = &rbd_root_dev;
5355 device_initialize(&rbd_dev->dev);
5356
5357 rbd_dev->rbd_client = rbdc;
5358 rbd_dev->spec = spec;
5359
5360 return rbd_dev;
5361}
5362
5363/*
5364 * Create a mapping rbd_dev.
5365 */
5366static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
5367 struct rbd_spec *spec,
5368 struct rbd_options *opts)
5369{
5370 struct rbd_device *rbd_dev;
5371
5372 rbd_dev = __rbd_dev_create(rbdc, spec);
5373 if (!rbd_dev)
5374 return NULL;
5375
5376 rbd_dev->opts = opts;
5377
5378 /* get an id and fill in device name */
5379 rbd_dev->dev_id = ida_simple_get(&rbd_dev_id_ida, 0,
5380 minor_to_rbd_dev_id(1 << MINORBITS),
5381 GFP_KERNEL);
5382 if (rbd_dev->dev_id < 0)
5383 goto fail_rbd_dev;
5384
5385 sprintf(rbd_dev->name, RBD_DRV_NAME "%d", rbd_dev->dev_id);
5386 rbd_dev->task_wq = alloc_ordered_workqueue("%s-tasks", WQ_MEM_RECLAIM,
5387 rbd_dev->name);
5388 if (!rbd_dev->task_wq)
5389 goto fail_dev_id;
5390
5391 /* we have a ref from do_rbd_add() */
5392 __module_get(THIS_MODULE);
5393
5394 dout("%s rbd_dev %p dev_id %d\n", __func__, rbd_dev, rbd_dev->dev_id);
5395 return rbd_dev;
5396
5397fail_dev_id:
5398 ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id);
5399fail_rbd_dev:
5400 rbd_dev_free(rbd_dev);
5401 return NULL;
5402}
5403
5404static void rbd_dev_destroy(struct rbd_device *rbd_dev)
5405{
5406 if (rbd_dev)
5407 put_device(&rbd_dev->dev);
5408}
5409
5410/*
5411 * Get the size and object order for an image snapshot, or if
5412 * snap_id is CEPH_NOSNAP, gets this information for the base
5413 * image.
5414 */
5415static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
5416 u8 *order, u64 *snap_size)
5417{
5418 __le64 snapid = cpu_to_le64(snap_id);
5419 int ret;
5420 struct {
5421 u8 order;
5422 __le64 size;
5423 } __attribute__ ((packed)) size_buf = { 0 };
5424
5425 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5426 &rbd_dev->header_oloc, "get_size",
5427 &snapid, sizeof(snapid),
5428 &size_buf, sizeof(size_buf));
5429 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5430 if (ret < 0)
5431 return ret;
5432 if (ret < sizeof (size_buf))
5433 return -ERANGE;
5434
5435 if (order) {
5436 *order = size_buf.order;
5437 dout(" order %u", (unsigned int)*order);
5438 }
5439 *snap_size = le64_to_cpu(size_buf.size);
5440
5441 dout(" snap_id 0x%016llx snap_size = %llu\n",
5442 (unsigned long long)snap_id,
5443 (unsigned long long)*snap_size);
5444
5445 return 0;
5446}
5447
5448static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
5449{
5450 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
5451 &rbd_dev->header.obj_order,
5452 &rbd_dev->header.image_size);
5453}
5454
5455static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
5456{
5457 size_t size;
5458 void *reply_buf;
5459 int ret;
5460 void *p;
5461
5462 /* Response will be an encoded string, which includes a length */
5463 size = sizeof(__le32) + RBD_OBJ_PREFIX_LEN_MAX;
5464 reply_buf = kzalloc(size, GFP_KERNEL);
5465 if (!reply_buf)
5466 return -ENOMEM;
5467
5468 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5469 &rbd_dev->header_oloc, "get_object_prefix",
5470 NULL, 0, reply_buf, size);
5471 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5472 if (ret < 0)
5473 goto out;
5474
5475 p = reply_buf;
5476 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
5477 p + ret, NULL, GFP_NOIO);
5478 ret = 0;
5479
5480 if (IS_ERR(rbd_dev->header.object_prefix)) {
5481 ret = PTR_ERR(rbd_dev->header.object_prefix);
5482 rbd_dev->header.object_prefix = NULL;
5483 } else {
5484 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix);
5485 }
5486out:
5487 kfree(reply_buf);
5488
5489 return ret;
5490}
5491
5492static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
5493 bool read_only, u64 *snap_features)
5494{
5495 struct {
5496 __le64 snap_id;
5497 u8 read_only;
5498 } features_in;
5499 struct {
5500 __le64 features;
5501 __le64 incompat;
5502 } __attribute__ ((packed)) features_buf = { 0 };
5503 u64 unsup;
5504 int ret;
5505
5506 features_in.snap_id = cpu_to_le64(snap_id);
5507 features_in.read_only = read_only;
5508
5509 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5510 &rbd_dev->header_oloc, "get_features",
5511 &features_in, sizeof(features_in),
5512 &features_buf, sizeof(features_buf));
5513 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5514 if (ret < 0)
5515 return ret;
5516 if (ret < sizeof (features_buf))
5517 return -ERANGE;
5518
5519 unsup = le64_to_cpu(features_buf.incompat) & ~RBD_FEATURES_SUPPORTED;
5520 if (unsup) {
5521 rbd_warn(rbd_dev, "image uses unsupported features: 0x%llx",
5522 unsup);
5523 return -ENXIO;
5524 }
5525
5526 *snap_features = le64_to_cpu(features_buf.features);
5527
5528 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
5529 (unsigned long long)snap_id,
5530 (unsigned long long)*snap_features,
5531 (unsigned long long)le64_to_cpu(features_buf.incompat));
5532
5533 return 0;
5534}
5535
5536static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
5537{
5538 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
5539 rbd_is_ro(rbd_dev),
5540 &rbd_dev->header.features);
5541}
5542
5543/*
5544 * These are generic image flags, but since they are used only for
5545 * object map, store them in rbd_dev->object_map_flags.
5546 *
5547 * For the same reason, this function is called only on object map
5548 * (re)load and not on header refresh.
5549 */
5550static int rbd_dev_v2_get_flags(struct rbd_device *rbd_dev)
5551{
5552 __le64 snapid = cpu_to_le64(rbd_dev->spec->snap_id);
5553 __le64 flags;
5554 int ret;
5555
5556 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5557 &rbd_dev->header_oloc, "get_flags",
5558 &snapid, sizeof(snapid),
5559 &flags, sizeof(flags));
5560 if (ret < 0)
5561 return ret;
5562 if (ret < sizeof(flags))
5563 return -EBADMSG;
5564
5565 rbd_dev->object_map_flags = le64_to_cpu(flags);
5566 return 0;
5567}
5568
5569struct parent_image_info {
5570 u64 pool_id;
5571 const char *pool_ns;
5572 const char *image_id;
5573 u64 snap_id;
5574
5575 bool has_overlap;
5576 u64 overlap;
5577};
5578
5579/*
5580 * The caller is responsible for @pii.
5581 */
5582static int decode_parent_image_spec(void **p, void *end,
5583 struct parent_image_info *pii)
5584{
5585 u8 struct_v;
5586 u32 struct_len;
5587 int ret;
5588
5589 ret = ceph_start_decoding(p, end, 1, "ParentImageSpec",
5590 &struct_v, &struct_len);
5591 if (ret)
5592 return ret;
5593
5594 ceph_decode_64_safe(p, end, pii->pool_id, e_inval);
5595 pii->pool_ns = ceph_extract_encoded_string(p, end, NULL, GFP_KERNEL);
5596 if (IS_ERR(pii->pool_ns)) {
5597 ret = PTR_ERR(pii->pool_ns);
5598 pii->pool_ns = NULL;
5599 return ret;
5600 }
5601 pii->image_id = ceph_extract_encoded_string(p, end, NULL, GFP_KERNEL);
5602 if (IS_ERR(pii->image_id)) {
5603 ret = PTR_ERR(pii->image_id);
5604 pii->image_id = NULL;
5605 return ret;
5606 }
5607 ceph_decode_64_safe(p, end, pii->snap_id, e_inval);
5608 return 0;
5609
5610e_inval:
5611 return -EINVAL;
5612}
5613
5614static int __get_parent_info(struct rbd_device *rbd_dev,
5615 struct page *req_page,
5616 struct page *reply_page,
5617 struct parent_image_info *pii)
5618{
5619 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
5620 size_t reply_len = PAGE_SIZE;
5621 void *p, *end;
5622 int ret;
5623
5624 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
5625 "rbd", "parent_get", CEPH_OSD_FLAG_READ,
5626 req_page, sizeof(u64), &reply_page, &reply_len);
5627 if (ret)
5628 return ret == -EOPNOTSUPP ? 1 : ret;
5629
5630 p = page_address(reply_page);
5631 end = p + reply_len;
5632 ret = decode_parent_image_spec(&p, end, pii);
5633 if (ret)
5634 return ret;
5635
5636 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
5637 "rbd", "parent_overlap_get", CEPH_OSD_FLAG_READ,
5638 req_page, sizeof(u64), &reply_page, &reply_len);
5639 if (ret)
5640 return ret;
5641
5642 p = page_address(reply_page);
5643 end = p + reply_len;
5644 ceph_decode_8_safe(&p, end, pii->has_overlap, e_inval);
5645 if (pii->has_overlap)
5646 ceph_decode_64_safe(&p, end, pii->overlap, e_inval);
5647
5648 return 0;
5649
5650e_inval:
5651 return -EINVAL;
5652}
5653
5654/*
5655 * The caller is responsible for @pii.
5656 */
5657static int __get_parent_info_legacy(struct rbd_device *rbd_dev,
5658 struct page *req_page,
5659 struct page *reply_page,
5660 struct parent_image_info *pii)
5661{
5662 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
5663 size_t reply_len = PAGE_SIZE;
5664 void *p, *end;
5665 int ret;
5666
5667 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
5668 "rbd", "get_parent", CEPH_OSD_FLAG_READ,
5669 req_page, sizeof(u64), &reply_page, &reply_len);
5670 if (ret)
5671 return ret;
5672
5673 p = page_address(reply_page);
5674 end = p + reply_len;
5675 ceph_decode_64_safe(&p, end, pii->pool_id, e_inval);
5676 pii->image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
5677 if (IS_ERR(pii->image_id)) {
5678 ret = PTR_ERR(pii->image_id);
5679 pii->image_id = NULL;
5680 return ret;
5681 }
5682 ceph_decode_64_safe(&p, end, pii->snap_id, e_inval);
5683 pii->has_overlap = true;
5684 ceph_decode_64_safe(&p, end, pii->overlap, e_inval);
5685
5686 return 0;
5687
5688e_inval:
5689 return -EINVAL;
5690}
5691
5692static int get_parent_info(struct rbd_device *rbd_dev,
5693 struct parent_image_info *pii)
5694{
5695 struct page *req_page, *reply_page;
5696 void *p;
5697 int ret;
5698
5699 req_page = alloc_page(GFP_KERNEL);
5700 if (!req_page)
5701 return -ENOMEM;
5702
5703 reply_page = alloc_page(GFP_KERNEL);
5704 if (!reply_page) {
5705 __free_page(req_page);
5706 return -ENOMEM;
5707 }
5708
5709 p = page_address(req_page);
5710 ceph_encode_64(&p, rbd_dev->spec->snap_id);
5711 ret = __get_parent_info(rbd_dev, req_page, reply_page, pii);
5712 if (ret > 0)
5713 ret = __get_parent_info_legacy(rbd_dev, req_page, reply_page,
5714 pii);
5715
5716 __free_page(req_page);
5717 __free_page(reply_page);
5718 return ret;
5719}
5720
5721static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
5722{
5723 struct rbd_spec *parent_spec;
5724 struct parent_image_info pii = { 0 };
5725 int ret;
5726
5727 parent_spec = rbd_spec_alloc();
5728 if (!parent_spec)
5729 return -ENOMEM;
5730
5731 ret = get_parent_info(rbd_dev, &pii);
5732 if (ret)
5733 goto out_err;
5734
5735 dout("%s pool_id %llu pool_ns %s image_id %s snap_id %llu has_overlap %d overlap %llu\n",
5736 __func__, pii.pool_id, pii.pool_ns, pii.image_id, pii.snap_id,
5737 pii.has_overlap, pii.overlap);
5738
5739 if (pii.pool_id == CEPH_NOPOOL || !pii.has_overlap) {
5740 /*
5741 * Either the parent never existed, or we have
5742 * record of it but the image got flattened so it no
5743 * longer has a parent. When the parent of a
5744 * layered image disappears we immediately set the
5745 * overlap to 0. The effect of this is that all new
5746 * requests will be treated as if the image had no
5747 * parent.
5748 *
5749 * If !pii.has_overlap, the parent image spec is not
5750 * applicable. It's there to avoid duplication in each
5751 * snapshot record.
5752 */
5753 if (rbd_dev->parent_overlap) {
5754 rbd_dev->parent_overlap = 0;
5755 rbd_dev_parent_put(rbd_dev);
5756 pr_info("%s: clone image has been flattened\n",
5757 rbd_dev->disk->disk_name);
5758 }
5759
5760 goto out; /* No parent? No problem. */
5761 }
5762
5763 /* The ceph file layout needs to fit pool id in 32 bits */
5764
5765 ret = -EIO;
5766 if (pii.pool_id > (u64)U32_MAX) {
5767 rbd_warn(NULL, "parent pool id too large (%llu > %u)",
5768 (unsigned long long)pii.pool_id, U32_MAX);
5769 goto out_err;
5770 }
5771
5772 /*
5773 * The parent won't change (except when the clone is
5774 * flattened, already handled that). So we only need to
5775 * record the parent spec we have not already done so.
5776 */
5777 if (!rbd_dev->parent_spec) {
5778 parent_spec->pool_id = pii.pool_id;
5779 if (pii.pool_ns && *pii.pool_ns) {
5780 parent_spec->pool_ns = pii.pool_ns;
5781 pii.pool_ns = NULL;
5782 }
5783 parent_spec->image_id = pii.image_id;
5784 pii.image_id = NULL;
5785 parent_spec->snap_id = pii.snap_id;
5786
5787 rbd_dev->parent_spec = parent_spec;
5788 parent_spec = NULL; /* rbd_dev now owns this */
5789 }
5790
5791 /*
5792 * We always update the parent overlap. If it's zero we issue
5793 * a warning, as we will proceed as if there was no parent.
5794 */
5795 if (!pii.overlap) {
5796 if (parent_spec) {
5797 /* refresh, careful to warn just once */
5798 if (rbd_dev->parent_overlap)
5799 rbd_warn(rbd_dev,
5800 "clone now standalone (overlap became 0)");
5801 } else {
5802 /* initial probe */
5803 rbd_warn(rbd_dev, "clone is standalone (overlap 0)");
5804 }
5805 }
5806 rbd_dev->parent_overlap = pii.overlap;
5807
5808out:
5809 ret = 0;
5810out_err:
5811 kfree(pii.pool_ns);
5812 kfree(pii.image_id);
5813 rbd_spec_put(parent_spec);
5814 return ret;
5815}
5816
5817static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
5818{
5819 struct {
5820 __le64 stripe_unit;
5821 __le64 stripe_count;
5822 } __attribute__ ((packed)) striping_info_buf = { 0 };
5823 size_t size = sizeof (striping_info_buf);
5824 void *p;
5825 int ret;
5826
5827 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5828 &rbd_dev->header_oloc, "get_stripe_unit_count",
5829 NULL, 0, &striping_info_buf, size);
5830 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5831 if (ret < 0)
5832 return ret;
5833 if (ret < size)
5834 return -ERANGE;
5835
5836 p = &striping_info_buf;
5837 rbd_dev->header.stripe_unit = ceph_decode_64(&p);
5838 rbd_dev->header.stripe_count = ceph_decode_64(&p);
5839 return 0;
5840}
5841
5842static int rbd_dev_v2_data_pool(struct rbd_device *rbd_dev)
5843{
5844 __le64 data_pool_id;
5845 int ret;
5846
5847 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5848 &rbd_dev->header_oloc, "get_data_pool",
5849 NULL, 0, &data_pool_id, sizeof(data_pool_id));
5850 if (ret < 0)
5851 return ret;
5852 if (ret < sizeof(data_pool_id))
5853 return -EBADMSG;
5854
5855 rbd_dev->header.data_pool_id = le64_to_cpu(data_pool_id);
5856 WARN_ON(rbd_dev->header.data_pool_id == CEPH_NOPOOL);
5857 return 0;
5858}
5859
5860static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
5861{
5862 CEPH_DEFINE_OID_ONSTACK(oid);
5863 size_t image_id_size;
5864 char *image_id;
5865 void *p;
5866 void *end;
5867 size_t size;
5868 void *reply_buf = NULL;
5869 size_t len = 0;
5870 char *image_name = NULL;
5871 int ret;
5872
5873 rbd_assert(!rbd_dev->spec->image_name);
5874
5875 len = strlen(rbd_dev->spec->image_id);
5876 image_id_size = sizeof (__le32) + len;
5877 image_id = kmalloc(image_id_size, GFP_KERNEL);
5878 if (!image_id)
5879 return NULL;
5880
5881 p = image_id;
5882 end = image_id + image_id_size;
5883 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
5884
5885 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
5886 reply_buf = kmalloc(size, GFP_KERNEL);
5887 if (!reply_buf)
5888 goto out;
5889
5890 ceph_oid_printf(&oid, "%s", RBD_DIRECTORY);
5891 ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc,
5892 "dir_get_name", image_id, image_id_size,
5893 reply_buf, size);
5894 if (ret < 0)
5895 goto out;
5896 p = reply_buf;
5897 end = reply_buf + ret;
5898
5899 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
5900 if (IS_ERR(image_name))
5901 image_name = NULL;
5902 else
5903 dout("%s: name is %s len is %zd\n", __func__, image_name, len);
5904out:
5905 kfree(reply_buf);
5906 kfree(image_id);
5907
5908 return image_name;
5909}
5910
5911static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
5912{
5913 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
5914 const char *snap_name;
5915 u32 which = 0;
5916
5917 /* Skip over names until we find the one we are looking for */
5918
5919 snap_name = rbd_dev->header.snap_names;
5920 while (which < snapc->num_snaps) {
5921 if (!strcmp(name, snap_name))
5922 return snapc->snaps[which];
5923 snap_name += strlen(snap_name) + 1;
5924 which++;
5925 }
5926 return CEPH_NOSNAP;
5927}
5928
5929static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
5930{
5931 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
5932 u32 which;
5933 bool found = false;
5934 u64 snap_id;
5935
5936 for (which = 0; !found && which < snapc->num_snaps; which++) {
5937 const char *snap_name;
5938
5939 snap_id = snapc->snaps[which];
5940 snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
5941 if (IS_ERR(snap_name)) {
5942 /* ignore no-longer existing snapshots */
5943 if (PTR_ERR(snap_name) == -ENOENT)
5944 continue;
5945 else
5946 break;
5947 }
5948 found = !strcmp(name, snap_name);
5949 kfree(snap_name);
5950 }
5951 return found ? snap_id : CEPH_NOSNAP;
5952}
5953
5954/*
5955 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
5956 * no snapshot by that name is found, or if an error occurs.
5957 */
5958static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
5959{
5960 if (rbd_dev->image_format == 1)
5961 return rbd_v1_snap_id_by_name(rbd_dev, name);
5962
5963 return rbd_v2_snap_id_by_name(rbd_dev, name);
5964}
5965
5966/*
5967 * An image being mapped will have everything but the snap id.
5968 */
5969static int rbd_spec_fill_snap_id(struct rbd_device *rbd_dev)
5970{
5971 struct rbd_spec *spec = rbd_dev->spec;
5972
5973 rbd_assert(spec->pool_id != CEPH_NOPOOL && spec->pool_name);
5974 rbd_assert(spec->image_id && spec->image_name);
5975 rbd_assert(spec->snap_name);
5976
5977 if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
5978 u64 snap_id;
5979
5980 snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
5981 if (snap_id == CEPH_NOSNAP)
5982 return -ENOENT;
5983
5984 spec->snap_id = snap_id;
5985 } else {
5986 spec->snap_id = CEPH_NOSNAP;
5987 }
5988
5989 return 0;
5990}
5991
5992/*
5993 * A parent image will have all ids but none of the names.
5994 *
5995 * All names in an rbd spec are dynamically allocated. It's OK if we
5996 * can't figure out the name for an image id.
5997 */
5998static int rbd_spec_fill_names(struct rbd_device *rbd_dev)
5999{
6000 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
6001 struct rbd_spec *spec = rbd_dev->spec;
6002 const char *pool_name;
6003 const char *image_name;
6004 const char *snap_name;
6005 int ret;
6006
6007 rbd_assert(spec->pool_id != CEPH_NOPOOL);
6008 rbd_assert(spec->image_id);
6009 rbd_assert(spec->snap_id != CEPH_NOSNAP);
6010
6011 /* Get the pool name; we have to make our own copy of this */
6012
6013 pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
6014 if (!pool_name) {
6015 rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
6016 return -EIO;
6017 }
6018 pool_name = kstrdup(pool_name, GFP_KERNEL);
6019 if (!pool_name)
6020 return -ENOMEM;
6021
6022 /* Fetch the image name; tolerate failure here */
6023
6024 image_name = rbd_dev_image_name(rbd_dev);
6025 if (!image_name)
6026 rbd_warn(rbd_dev, "unable to get image name");
6027
6028 /* Fetch the snapshot name */
6029
6030 snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
6031 if (IS_ERR(snap_name)) {
6032 ret = PTR_ERR(snap_name);
6033 goto out_err;
6034 }
6035
6036 spec->pool_name = pool_name;
6037 spec->image_name = image_name;
6038 spec->snap_name = snap_name;
6039
6040 return 0;
6041
6042out_err:
6043 kfree(image_name);
6044 kfree(pool_name);
6045 return ret;
6046}
6047
6048static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
6049{
6050 size_t size;
6051 int ret;
6052 void *reply_buf;
6053 void *p;
6054 void *end;
6055 u64 seq;
6056 u32 snap_count;
6057 struct ceph_snap_context *snapc;
6058 u32 i;
6059
6060 /*
6061 * We'll need room for the seq value (maximum snapshot id),
6062 * snapshot count, and array of that many snapshot ids.
6063 * For now we have a fixed upper limit on the number we're
6064 * prepared to receive.
6065 */
6066 size = sizeof (__le64) + sizeof (__le32) +
6067 RBD_MAX_SNAP_COUNT * sizeof (__le64);
6068 reply_buf = kzalloc(size, GFP_KERNEL);
6069 if (!reply_buf)
6070 return -ENOMEM;
6071
6072 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
6073 &rbd_dev->header_oloc, "get_snapcontext",
6074 NULL, 0, reply_buf, size);
6075 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
6076 if (ret < 0)
6077 goto out;
6078
6079 p = reply_buf;
6080 end = reply_buf + ret;
6081 ret = -ERANGE;
6082 ceph_decode_64_safe(&p, end, seq, out);
6083 ceph_decode_32_safe(&p, end, snap_count, out);
6084
6085 /*
6086 * Make sure the reported number of snapshot ids wouldn't go
6087 * beyond the end of our buffer. But before checking that,
6088 * make sure the computed size of the snapshot context we
6089 * allocate is representable in a size_t.
6090 */
6091 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
6092 / sizeof (u64)) {
6093 ret = -EINVAL;
6094 goto out;
6095 }
6096 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
6097 goto out;
6098 ret = 0;
6099
6100 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
6101 if (!snapc) {
6102 ret = -ENOMEM;
6103 goto out;
6104 }
6105 snapc->seq = seq;
6106 for (i = 0; i < snap_count; i++)
6107 snapc->snaps[i] = ceph_decode_64(&p);
6108
6109 ceph_put_snap_context(rbd_dev->header.snapc);
6110 rbd_dev->header.snapc = snapc;
6111
6112 dout(" snap context seq = %llu, snap_count = %u\n",
6113 (unsigned long long)seq, (unsigned int)snap_count);
6114out:
6115 kfree(reply_buf);
6116
6117 return ret;
6118}
6119
6120static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
6121 u64 snap_id)
6122{
6123 size_t size;
6124 void *reply_buf;
6125 __le64 snapid;
6126 int ret;
6127 void *p;
6128 void *end;
6129 char *snap_name;
6130
6131 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
6132 reply_buf = kmalloc(size, GFP_KERNEL);
6133 if (!reply_buf)
6134 return ERR_PTR(-ENOMEM);
6135
6136 snapid = cpu_to_le64(snap_id);
6137 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
6138 &rbd_dev->header_oloc, "get_snapshot_name",
6139 &snapid, sizeof(snapid), reply_buf, size);
6140 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
6141 if (ret < 0) {
6142 snap_name = ERR_PTR(ret);
6143 goto out;
6144 }
6145
6146 p = reply_buf;
6147 end = reply_buf + ret;
6148 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
6149 if (IS_ERR(snap_name))
6150 goto out;
6151
6152 dout(" snap_id 0x%016llx snap_name = %s\n",
6153 (unsigned long long)snap_id, snap_name);
6154out:
6155 kfree(reply_buf);
6156
6157 return snap_name;
6158}
6159
6160static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
6161{
6162 bool first_time = rbd_dev->header.object_prefix == NULL;
6163 int ret;
6164
6165 ret = rbd_dev_v2_image_size(rbd_dev);
6166 if (ret)
6167 return ret;
6168
6169 if (first_time) {
6170 ret = rbd_dev_v2_header_onetime(rbd_dev);
6171 if (ret)
6172 return ret;
6173 }
6174
6175 ret = rbd_dev_v2_snap_context(rbd_dev);
6176 if (ret && first_time) {
6177 kfree(rbd_dev->header.object_prefix);
6178 rbd_dev->header.object_prefix = NULL;
6179 }
6180
6181 return ret;
6182}
6183
6184static int rbd_dev_header_info(struct rbd_device *rbd_dev)
6185{
6186 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
6187
6188 if (rbd_dev->image_format == 1)
6189 return rbd_dev_v1_header_info(rbd_dev);
6190
6191 return rbd_dev_v2_header_info(rbd_dev);
6192}
6193
6194/*
6195 * Skips over white space at *buf, and updates *buf to point to the
6196 * first found non-space character (if any). Returns the length of
6197 * the token (string of non-white space characters) found. Note
6198 * that *buf must be terminated with '\0'.
6199 */
6200static inline size_t next_token(const char **buf)
6201{
6202 /*
6203 * These are the characters that produce nonzero for
6204 * isspace() in the "C" and "POSIX" locales.
6205 */
6206 const char *spaces = " \f\n\r\t\v";
6207
6208 *buf += strspn(*buf, spaces); /* Find start of token */
6209
6210 return strcspn(*buf, spaces); /* Return token length */
6211}
6212
6213/*
6214 * Finds the next token in *buf, dynamically allocates a buffer big
6215 * enough to hold a copy of it, and copies the token into the new
6216 * buffer. The copy is guaranteed to be terminated with '\0'. Note
6217 * that a duplicate buffer is created even for a zero-length token.
6218 *
6219 * Returns a pointer to the newly-allocated duplicate, or a null
6220 * pointer if memory for the duplicate was not available. If
6221 * the lenp argument is a non-null pointer, the length of the token
6222 * (not including the '\0') is returned in *lenp.
6223 *
6224 * If successful, the *buf pointer will be updated to point beyond
6225 * the end of the found token.
6226 *
6227 * Note: uses GFP_KERNEL for allocation.
6228 */
6229static inline char *dup_token(const char **buf, size_t *lenp)
6230{
6231 char *dup;
6232 size_t len;
6233
6234 len = next_token(buf);
6235 dup = kmemdup(*buf, len + 1, GFP_KERNEL);
6236 if (!dup)
6237 return NULL;
6238 *(dup + len) = '\0';
6239 *buf += len;
6240
6241 if (lenp)
6242 *lenp = len;
6243
6244 return dup;
6245}
6246
6247static int rbd_parse_param(struct fs_parameter *param,
6248 struct rbd_parse_opts_ctx *pctx)
6249{
6250 struct rbd_options *opt = pctx->opts;
6251 struct fs_parse_result result;
6252 struct p_log log = {.prefix = "rbd"};
6253 int token, ret;
6254
6255 ret = ceph_parse_param(param, pctx->copts, NULL);
6256 if (ret != -ENOPARAM)
6257 return ret;
6258
6259 token = __fs_parse(&log, rbd_parameters, param, &result);
6260 dout("%s fs_parse '%s' token %d\n", __func__, param->key, token);
6261 if (token < 0) {
6262 if (token == -ENOPARAM)
6263 return inval_plog(&log, "Unknown parameter '%s'",
6264 param->key);
6265 return token;
6266 }
6267
6268 switch (token) {
6269 case Opt_queue_depth:
6270 if (result.uint_32 < 1)
6271 goto out_of_range;
6272 opt->queue_depth = result.uint_32;
6273 break;
6274 case Opt_alloc_size:
6275 if (result.uint_32 < SECTOR_SIZE)
6276 goto out_of_range;
6277 if (!is_power_of_2(result.uint_32))
6278 return inval_plog(&log, "alloc_size must be a power of 2");
6279 opt->alloc_size = result.uint_32;
6280 break;
6281 case Opt_lock_timeout:
6282 /* 0 is "wait forever" (i.e. infinite timeout) */
6283 if (result.uint_32 > INT_MAX / 1000)
6284 goto out_of_range;
6285 opt->lock_timeout = msecs_to_jiffies(result.uint_32 * 1000);
6286 break;
6287 case Opt_pool_ns:
6288 kfree(pctx->spec->pool_ns);
6289 pctx->spec->pool_ns = param->string;
6290 param->string = NULL;
6291 break;
6292 case Opt_compression_hint:
6293 switch (result.uint_32) {
6294 case Opt_compression_hint_none:
6295 opt->alloc_hint_flags &=
6296 ~(CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE |
6297 CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE);
6298 break;
6299 case Opt_compression_hint_compressible:
6300 opt->alloc_hint_flags |=
6301 CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE;
6302 opt->alloc_hint_flags &=
6303 ~CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE;
6304 break;
6305 case Opt_compression_hint_incompressible:
6306 opt->alloc_hint_flags |=
6307 CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE;
6308 opt->alloc_hint_flags &=
6309 ~CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE;
6310 break;
6311 default:
6312 BUG();
6313 }
6314 break;
6315 case Opt_read_only:
6316 opt->read_only = true;
6317 break;
6318 case Opt_read_write:
6319 opt->read_only = false;
6320 break;
6321 case Opt_lock_on_read:
6322 opt->lock_on_read = true;
6323 break;
6324 case Opt_exclusive:
6325 opt->exclusive = true;
6326 break;
6327 case Opt_notrim:
6328 opt->trim = false;
6329 break;
6330 default:
6331 BUG();
6332 }
6333
6334 return 0;
6335
6336out_of_range:
6337 return inval_plog(&log, "%s out of range", param->key);
6338}
6339
6340/*
6341 * This duplicates most of generic_parse_monolithic(), untying it from
6342 * fs_context and skipping standard superblock and security options.
6343 */
6344static int rbd_parse_options(char *options, struct rbd_parse_opts_ctx *pctx)
6345{
6346 char *key;
6347 int ret = 0;
6348
6349 dout("%s '%s'\n", __func__, options);
6350 while ((key = strsep(&options, ",")) != NULL) {
6351 if (*key) {
6352 struct fs_parameter param = {
6353 .key = key,
6354 .type = fs_value_is_flag,
6355 };
6356 char *value = strchr(key, '=');
6357 size_t v_len = 0;
6358
6359 if (value) {
6360 if (value == key)
6361 continue;
6362 *value++ = 0;
6363 v_len = strlen(value);
6364 param.string = kmemdup_nul(value, v_len,
6365 GFP_KERNEL);
6366 if (!param.string)
6367 return -ENOMEM;
6368 param.type = fs_value_is_string;
6369 }
6370 param.size = v_len;
6371
6372 ret = rbd_parse_param(¶m, pctx);
6373 kfree(param.string);
6374 if (ret)
6375 break;
6376 }
6377 }
6378
6379 return ret;
6380}
6381
6382/*
6383 * Parse the options provided for an "rbd add" (i.e., rbd image
6384 * mapping) request. These arrive via a write to /sys/bus/rbd/add,
6385 * and the data written is passed here via a NUL-terminated buffer.
6386 * Returns 0 if successful or an error code otherwise.
6387 *
6388 * The information extracted from these options is recorded in
6389 * the other parameters which return dynamically-allocated
6390 * structures:
6391 * ceph_opts
6392 * The address of a pointer that will refer to a ceph options
6393 * structure. Caller must release the returned pointer using
6394 * ceph_destroy_options() when it is no longer needed.
6395 * rbd_opts
6396 * Address of an rbd options pointer. Fully initialized by
6397 * this function; caller must release with kfree().
6398 * spec
6399 * Address of an rbd image specification pointer. Fully
6400 * initialized by this function based on parsed options.
6401 * Caller must release with rbd_spec_put().
6402 *
6403 * The options passed take this form:
6404 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
6405 * where:
6406 * <mon_addrs>
6407 * A comma-separated list of one or more monitor addresses.
6408 * A monitor address is an ip address, optionally followed
6409 * by a port number (separated by a colon).
6410 * I.e.: ip1[:port1][,ip2[:port2]...]
6411 * <options>
6412 * A comma-separated list of ceph and/or rbd options.
6413 * <pool_name>
6414 * The name of the rados pool containing the rbd image.
6415 * <image_name>
6416 * The name of the image in that pool to map.
6417 * <snap_id>
6418 * An optional snapshot id. If provided, the mapping will
6419 * present data from the image at the time that snapshot was
6420 * created. The image head is used if no snapshot id is
6421 * provided. Snapshot mappings are always read-only.
6422 */
6423static int rbd_add_parse_args(const char *buf,
6424 struct ceph_options **ceph_opts,
6425 struct rbd_options **opts,
6426 struct rbd_spec **rbd_spec)
6427{
6428 size_t len;
6429 char *options;
6430 const char *mon_addrs;
6431 char *snap_name;
6432 size_t mon_addrs_size;
6433 struct rbd_parse_opts_ctx pctx = { 0 };
6434 int ret;
6435
6436 /* The first four tokens are required */
6437
6438 len = next_token(&buf);
6439 if (!len) {
6440 rbd_warn(NULL, "no monitor address(es) provided");
6441 return -EINVAL;
6442 }
6443 mon_addrs = buf;
6444 mon_addrs_size = len;
6445 buf += len;
6446
6447 ret = -EINVAL;
6448 options = dup_token(&buf, NULL);
6449 if (!options)
6450 return -ENOMEM;
6451 if (!*options) {
6452 rbd_warn(NULL, "no options provided");
6453 goto out_err;
6454 }
6455
6456 pctx.spec = rbd_spec_alloc();
6457 if (!pctx.spec)
6458 goto out_mem;
6459
6460 pctx.spec->pool_name = dup_token(&buf, NULL);
6461 if (!pctx.spec->pool_name)
6462 goto out_mem;
6463 if (!*pctx.spec->pool_name) {
6464 rbd_warn(NULL, "no pool name provided");
6465 goto out_err;
6466 }
6467
6468 pctx.spec->image_name = dup_token(&buf, NULL);
6469 if (!pctx.spec->image_name)
6470 goto out_mem;
6471 if (!*pctx.spec->image_name) {
6472 rbd_warn(NULL, "no image name provided");
6473 goto out_err;
6474 }
6475
6476 /*
6477 * Snapshot name is optional; default is to use "-"
6478 * (indicating the head/no snapshot).
6479 */
6480 len = next_token(&buf);
6481 if (!len) {
6482 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
6483 len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
6484 } else if (len > RBD_MAX_SNAP_NAME_LEN) {
6485 ret = -ENAMETOOLONG;
6486 goto out_err;
6487 }
6488 snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
6489 if (!snap_name)
6490 goto out_mem;
6491 *(snap_name + len) = '\0';
6492 pctx.spec->snap_name = snap_name;
6493
6494 pctx.copts = ceph_alloc_options();
6495 if (!pctx.copts)
6496 goto out_mem;
6497
6498 /* Initialize all rbd options to the defaults */
6499
6500 pctx.opts = kzalloc(sizeof(*pctx.opts), GFP_KERNEL);
6501 if (!pctx.opts)
6502 goto out_mem;
6503
6504 pctx.opts->read_only = RBD_READ_ONLY_DEFAULT;
6505 pctx.opts->queue_depth = RBD_QUEUE_DEPTH_DEFAULT;
6506 pctx.opts->alloc_size = RBD_ALLOC_SIZE_DEFAULT;
6507 pctx.opts->lock_timeout = RBD_LOCK_TIMEOUT_DEFAULT;
6508 pctx.opts->lock_on_read = RBD_LOCK_ON_READ_DEFAULT;
6509 pctx.opts->exclusive = RBD_EXCLUSIVE_DEFAULT;
6510 pctx.opts->trim = RBD_TRIM_DEFAULT;
6511
6512 ret = ceph_parse_mon_ips(mon_addrs, mon_addrs_size, pctx.copts, NULL);
6513 if (ret)
6514 goto out_err;
6515
6516 ret = rbd_parse_options(options, &pctx);
6517 if (ret)
6518 goto out_err;
6519
6520 *ceph_opts = pctx.copts;
6521 *opts = pctx.opts;
6522 *rbd_spec = pctx.spec;
6523 kfree(options);
6524 return 0;
6525
6526out_mem:
6527 ret = -ENOMEM;
6528out_err:
6529 kfree(pctx.opts);
6530 ceph_destroy_options(pctx.copts);
6531 rbd_spec_put(pctx.spec);
6532 kfree(options);
6533 return ret;
6534}
6535
6536static void rbd_dev_image_unlock(struct rbd_device *rbd_dev)
6537{
6538 down_write(&rbd_dev->lock_rwsem);
6539 if (__rbd_is_lock_owner(rbd_dev))
6540 __rbd_release_lock(rbd_dev);
6541 up_write(&rbd_dev->lock_rwsem);
6542}
6543
6544/*
6545 * If the wait is interrupted, an error is returned even if the lock
6546 * was successfully acquired. rbd_dev_image_unlock() will release it
6547 * if needed.
6548 */
6549static int rbd_add_acquire_lock(struct rbd_device *rbd_dev)
6550{
6551 long ret;
6552
6553 if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK)) {
6554 if (!rbd_dev->opts->exclusive && !rbd_dev->opts->lock_on_read)
6555 return 0;
6556
6557 rbd_warn(rbd_dev, "exclusive-lock feature is not enabled");
6558 return -EINVAL;
6559 }
6560
6561 if (rbd_is_ro(rbd_dev))
6562 return 0;
6563
6564 rbd_assert(!rbd_is_lock_owner(rbd_dev));
6565 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
6566 ret = wait_for_completion_killable_timeout(&rbd_dev->acquire_wait,
6567 ceph_timeout_jiffies(rbd_dev->opts->lock_timeout));
6568 if (ret > 0) {
6569 ret = rbd_dev->acquire_err;
6570 } else {
6571 cancel_delayed_work_sync(&rbd_dev->lock_dwork);
6572 if (!ret)
6573 ret = -ETIMEDOUT;
6574 }
6575
6576 if (ret) {
6577 rbd_warn(rbd_dev, "failed to acquire exclusive lock: %ld", ret);
6578 return ret;
6579 }
6580
6581 /*
6582 * The lock may have been released by now, unless automatic lock
6583 * transitions are disabled.
6584 */
6585 rbd_assert(!rbd_dev->opts->exclusive || rbd_is_lock_owner(rbd_dev));
6586 return 0;
6587}
6588
6589/*
6590 * An rbd format 2 image has a unique identifier, distinct from the
6591 * name given to it by the user. Internally, that identifier is
6592 * what's used to specify the names of objects related to the image.
6593 *
6594 * A special "rbd id" object is used to map an rbd image name to its
6595 * id. If that object doesn't exist, then there is no v2 rbd image
6596 * with the supplied name.
6597 *
6598 * This function will record the given rbd_dev's image_id field if
6599 * it can be determined, and in that case will return 0. If any
6600 * errors occur a negative errno will be returned and the rbd_dev's
6601 * image_id field will be unchanged (and should be NULL).
6602 */
6603static int rbd_dev_image_id(struct rbd_device *rbd_dev)
6604{
6605 int ret;
6606 size_t size;
6607 CEPH_DEFINE_OID_ONSTACK(oid);
6608 void *response;
6609 char *image_id;
6610
6611 /*
6612 * When probing a parent image, the image id is already
6613 * known (and the image name likely is not). There's no
6614 * need to fetch the image id again in this case. We
6615 * do still need to set the image format though.
6616 */
6617 if (rbd_dev->spec->image_id) {
6618 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;
6619
6620 return 0;
6621 }
6622
6623 /*
6624 * First, see if the format 2 image id file exists, and if
6625 * so, get the image's persistent id from it.
6626 */
6627 ret = ceph_oid_aprintf(&oid, GFP_KERNEL, "%s%s", RBD_ID_PREFIX,
6628 rbd_dev->spec->image_name);
6629 if (ret)
6630 return ret;
6631
6632 dout("rbd id object name is %s\n", oid.name);
6633
6634 /* Response will be an encoded string, which includes a length */
6635 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
6636 response = kzalloc(size, GFP_NOIO);
6637 if (!response) {
6638 ret = -ENOMEM;
6639 goto out;
6640 }
6641
6642 /* If it doesn't exist we'll assume it's a format 1 image */
6643
6644 ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc,
6645 "get_id", NULL, 0,
6646 response, size);
6647 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
6648 if (ret == -ENOENT) {
6649 image_id = kstrdup("", GFP_KERNEL);
6650 ret = image_id ? 0 : -ENOMEM;
6651 if (!ret)
6652 rbd_dev->image_format = 1;
6653 } else if (ret >= 0) {
6654 void *p = response;
6655
6656 image_id = ceph_extract_encoded_string(&p, p + ret,
6657 NULL, GFP_NOIO);
6658 ret = PTR_ERR_OR_ZERO(image_id);
6659 if (!ret)
6660 rbd_dev->image_format = 2;
6661 }
6662
6663 if (!ret) {
6664 rbd_dev->spec->image_id = image_id;
6665 dout("image_id is %s\n", image_id);
6666 }
6667out:
6668 kfree(response);
6669 ceph_oid_destroy(&oid);
6670 return ret;
6671}
6672
6673/*
6674 * Undo whatever state changes are made by v1 or v2 header info
6675 * call.
6676 */
6677static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
6678{
6679 struct rbd_image_header *header;
6680
6681 rbd_dev_parent_put(rbd_dev);
6682 rbd_object_map_free(rbd_dev);
6683 rbd_dev_mapping_clear(rbd_dev);
6684
6685 /* Free dynamic fields from the header, then zero it out */
6686
6687 header = &rbd_dev->header;
6688 ceph_put_snap_context(header->snapc);
6689 kfree(header->snap_sizes);
6690 kfree(header->snap_names);
6691 kfree(header->object_prefix);
6692 memset(header, 0, sizeof (*header));
6693}
6694
6695static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev)
6696{
6697 int ret;
6698
6699 ret = rbd_dev_v2_object_prefix(rbd_dev);
6700 if (ret)
6701 goto out_err;
6702
6703 /*
6704 * Get the and check features for the image. Currently the
6705 * features are assumed to never change.
6706 */
6707 ret = rbd_dev_v2_features(rbd_dev);
6708 if (ret)
6709 goto out_err;
6710
6711 /* If the image supports fancy striping, get its parameters */
6712
6713 if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
6714 ret = rbd_dev_v2_striping_info(rbd_dev);
6715 if (ret < 0)
6716 goto out_err;
6717 }
6718
6719 if (rbd_dev->header.features & RBD_FEATURE_DATA_POOL) {
6720 ret = rbd_dev_v2_data_pool(rbd_dev);
6721 if (ret)
6722 goto out_err;
6723 }
6724
6725 rbd_init_layout(rbd_dev);
6726 return 0;
6727
6728out_err:
6729 rbd_dev->header.features = 0;
6730 kfree(rbd_dev->header.object_prefix);
6731 rbd_dev->header.object_prefix = NULL;
6732 return ret;
6733}
6734
6735/*
6736 * @depth is rbd_dev_image_probe() -> rbd_dev_probe_parent() ->
6737 * rbd_dev_image_probe() recursion depth, which means it's also the
6738 * length of the already discovered part of the parent chain.
6739 */
6740static int rbd_dev_probe_parent(struct rbd_device *rbd_dev, int depth)
6741{
6742 struct rbd_device *parent = NULL;
6743 int ret;
6744
6745 if (!rbd_dev->parent_spec)
6746 return 0;
6747
6748 if (++depth > RBD_MAX_PARENT_CHAIN_LEN) {
6749 pr_info("parent chain is too long (%d)\n", depth);
6750 ret = -EINVAL;
6751 goto out_err;
6752 }
6753
6754 parent = __rbd_dev_create(rbd_dev->rbd_client, rbd_dev->parent_spec);
6755 if (!parent) {
6756 ret = -ENOMEM;
6757 goto out_err;
6758 }
6759
6760 /*
6761 * Images related by parent/child relationships always share
6762 * rbd_client and spec/parent_spec, so bump their refcounts.
6763 */
6764 __rbd_get_client(rbd_dev->rbd_client);
6765 rbd_spec_get(rbd_dev->parent_spec);
6766
6767 __set_bit(RBD_DEV_FLAG_READONLY, &parent->flags);
6768
6769 ret = rbd_dev_image_probe(parent, depth);
6770 if (ret < 0)
6771 goto out_err;
6772
6773 rbd_dev->parent = parent;
6774 atomic_set(&rbd_dev->parent_ref, 1);
6775 return 0;
6776
6777out_err:
6778 rbd_dev_unparent(rbd_dev);
6779 rbd_dev_destroy(parent);
6780 return ret;
6781}
6782
6783static void rbd_dev_device_release(struct rbd_device *rbd_dev)
6784{
6785 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
6786 rbd_free_disk(rbd_dev);
6787 if (!single_major)
6788 unregister_blkdev(rbd_dev->major, rbd_dev->name);
6789}
6790
6791/*
6792 * rbd_dev->header_rwsem must be locked for write and will be unlocked
6793 * upon return.
6794 */
6795static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
6796{
6797 int ret;
6798
6799 /* Record our major and minor device numbers. */
6800
6801 if (!single_major) {
6802 ret = register_blkdev(0, rbd_dev->name);
6803 if (ret < 0)
6804 goto err_out_unlock;
6805
6806 rbd_dev->major = ret;
6807 rbd_dev->minor = 0;
6808 } else {
6809 rbd_dev->major = rbd_major;
6810 rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id);
6811 }
6812
6813 /* Set up the blkdev mapping. */
6814
6815 ret = rbd_init_disk(rbd_dev);
6816 if (ret)
6817 goto err_out_blkdev;
6818
6819 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
6820 set_disk_ro(rbd_dev->disk, rbd_is_ro(rbd_dev));
6821
6822 ret = dev_set_name(&rbd_dev->dev, "%d", rbd_dev->dev_id);
6823 if (ret)
6824 goto err_out_disk;
6825
6826 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
6827 up_write(&rbd_dev->header_rwsem);
6828 return 0;
6829
6830err_out_disk:
6831 rbd_free_disk(rbd_dev);
6832err_out_blkdev:
6833 if (!single_major)
6834 unregister_blkdev(rbd_dev->major, rbd_dev->name);
6835err_out_unlock:
6836 up_write(&rbd_dev->header_rwsem);
6837 return ret;
6838}
6839
6840static int rbd_dev_header_name(struct rbd_device *rbd_dev)
6841{
6842 struct rbd_spec *spec = rbd_dev->spec;
6843 int ret;
6844
6845 /* Record the header object name for this rbd image. */
6846
6847 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
6848 if (rbd_dev->image_format == 1)
6849 ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s",
6850 spec->image_name, RBD_SUFFIX);
6851 else
6852 ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s",
6853 RBD_HEADER_PREFIX, spec->image_id);
6854
6855 return ret;
6856}
6857
6858static void rbd_print_dne(struct rbd_device *rbd_dev, bool is_snap)
6859{
6860 if (!is_snap) {
6861 pr_info("image %s/%s%s%s does not exist\n",
6862 rbd_dev->spec->pool_name,
6863 rbd_dev->spec->pool_ns ?: "",
6864 rbd_dev->spec->pool_ns ? "/" : "",
6865 rbd_dev->spec->image_name);
6866 } else {
6867 pr_info("snap %s/%s%s%s@%s does not exist\n",
6868 rbd_dev->spec->pool_name,
6869 rbd_dev->spec->pool_ns ?: "",
6870 rbd_dev->spec->pool_ns ? "/" : "",
6871 rbd_dev->spec->image_name,
6872 rbd_dev->spec->snap_name);
6873 }
6874}
6875
6876static void rbd_dev_image_release(struct rbd_device *rbd_dev)
6877{
6878 if (!rbd_is_ro(rbd_dev))
6879 rbd_unregister_watch(rbd_dev);
6880
6881 rbd_dev_unprobe(rbd_dev);
6882 rbd_dev->image_format = 0;
6883 kfree(rbd_dev->spec->image_id);
6884 rbd_dev->spec->image_id = NULL;
6885}
6886
6887/*
6888 * Probe for the existence of the header object for the given rbd
6889 * device. If this image is the one being mapped (i.e., not a
6890 * parent), initiate a watch on its header object before using that
6891 * object to get detailed information about the rbd image.
6892 *
6893 * On success, returns with header_rwsem held for write if called
6894 * with @depth == 0.
6895 */
6896static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth)
6897{
6898 bool need_watch = !rbd_is_ro(rbd_dev);
6899 int ret;
6900
6901 /*
6902 * Get the id from the image id object. Unless there's an
6903 * error, rbd_dev->spec->image_id will be filled in with
6904 * a dynamically-allocated string, and rbd_dev->image_format
6905 * will be set to either 1 or 2.
6906 */
6907 ret = rbd_dev_image_id(rbd_dev);
6908 if (ret)
6909 return ret;
6910
6911 ret = rbd_dev_header_name(rbd_dev);
6912 if (ret)
6913 goto err_out_format;
6914
6915 if (need_watch) {
6916 ret = rbd_register_watch(rbd_dev);
6917 if (ret) {
6918 if (ret == -ENOENT)
6919 rbd_print_dne(rbd_dev, false);
6920 goto err_out_format;
6921 }
6922 }
6923
6924 if (!depth)
6925 down_write(&rbd_dev->header_rwsem);
6926
6927 ret = rbd_dev_header_info(rbd_dev);
6928 if (ret) {
6929 if (ret == -ENOENT && !need_watch)
6930 rbd_print_dne(rbd_dev, false);
6931 goto err_out_probe;
6932 }
6933
6934 /*
6935 * If this image is the one being mapped, we have pool name and
6936 * id, image name and id, and snap name - need to fill snap id.
6937 * Otherwise this is a parent image, identified by pool, image
6938 * and snap ids - need to fill in names for those ids.
6939 */
6940 if (!depth)
6941 ret = rbd_spec_fill_snap_id(rbd_dev);
6942 else
6943 ret = rbd_spec_fill_names(rbd_dev);
6944 if (ret) {
6945 if (ret == -ENOENT)
6946 rbd_print_dne(rbd_dev, true);
6947 goto err_out_probe;
6948 }
6949
6950 ret = rbd_dev_mapping_set(rbd_dev);
6951 if (ret)
6952 goto err_out_probe;
6953
6954 if (rbd_is_snap(rbd_dev) &&
6955 (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP)) {
6956 ret = rbd_object_map_load(rbd_dev);
6957 if (ret)
6958 goto err_out_probe;
6959 }
6960
6961 if (rbd_dev->header.features & RBD_FEATURE_LAYERING) {
6962 ret = rbd_dev_v2_parent_info(rbd_dev);
6963 if (ret)
6964 goto err_out_probe;
6965 }
6966
6967 ret = rbd_dev_probe_parent(rbd_dev, depth);
6968 if (ret)
6969 goto err_out_probe;
6970
6971 dout("discovered format %u image, header name is %s\n",
6972 rbd_dev->image_format, rbd_dev->header_oid.name);
6973 return 0;
6974
6975err_out_probe:
6976 if (!depth)
6977 up_write(&rbd_dev->header_rwsem);
6978 if (need_watch)
6979 rbd_unregister_watch(rbd_dev);
6980 rbd_dev_unprobe(rbd_dev);
6981err_out_format:
6982 rbd_dev->image_format = 0;
6983 kfree(rbd_dev->spec->image_id);
6984 rbd_dev->spec->image_id = NULL;
6985 return ret;
6986}
6987
6988static ssize_t do_rbd_add(struct bus_type *bus,
6989 const char *buf,
6990 size_t count)
6991{
6992 struct rbd_device *rbd_dev = NULL;
6993 struct ceph_options *ceph_opts = NULL;
6994 struct rbd_options *rbd_opts = NULL;
6995 struct rbd_spec *spec = NULL;
6996 struct rbd_client *rbdc;
6997 int rc;
6998
6999 if (!capable(CAP_SYS_ADMIN))
7000 return -EPERM;
7001
7002 if (!try_module_get(THIS_MODULE))
7003 return -ENODEV;
7004
7005 /* parse add command */
7006 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
7007 if (rc < 0)
7008 goto out;
7009
7010 rbdc = rbd_get_client(ceph_opts);
7011 if (IS_ERR(rbdc)) {
7012 rc = PTR_ERR(rbdc);
7013 goto err_out_args;
7014 }
7015
7016 /* pick the pool */
7017 rc = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, spec->pool_name);
7018 if (rc < 0) {
7019 if (rc == -ENOENT)
7020 pr_info("pool %s does not exist\n", spec->pool_name);
7021 goto err_out_client;
7022 }
7023 spec->pool_id = (u64)rc;
7024
7025 rbd_dev = rbd_dev_create(rbdc, spec, rbd_opts);
7026 if (!rbd_dev) {
7027 rc = -ENOMEM;
7028 goto err_out_client;
7029 }
7030 rbdc = NULL; /* rbd_dev now owns this */
7031 spec = NULL; /* rbd_dev now owns this */
7032 rbd_opts = NULL; /* rbd_dev now owns this */
7033
7034 /* if we are mapping a snapshot it will be a read-only mapping */
7035 if (rbd_dev->opts->read_only ||
7036 strcmp(rbd_dev->spec->snap_name, RBD_SNAP_HEAD_NAME))
7037 __set_bit(RBD_DEV_FLAG_READONLY, &rbd_dev->flags);
7038
7039 rbd_dev->config_info = kstrdup(buf, GFP_KERNEL);
7040 if (!rbd_dev->config_info) {
7041 rc = -ENOMEM;
7042 goto err_out_rbd_dev;
7043 }
7044
7045 rc = rbd_dev_image_probe(rbd_dev, 0);
7046 if (rc < 0)
7047 goto err_out_rbd_dev;
7048
7049 if (rbd_dev->opts->alloc_size > rbd_dev->layout.object_size) {
7050 rbd_warn(rbd_dev, "alloc_size adjusted to %u",
7051 rbd_dev->layout.object_size);
7052 rbd_dev->opts->alloc_size = rbd_dev->layout.object_size;
7053 }
7054
7055 rc = rbd_dev_device_setup(rbd_dev);
7056 if (rc)
7057 goto err_out_image_probe;
7058
7059 rc = rbd_add_acquire_lock(rbd_dev);
7060 if (rc)
7061 goto err_out_image_lock;
7062
7063 /* Everything's ready. Announce the disk to the world. */
7064
7065 rc = device_add(&rbd_dev->dev);
7066 if (rc)
7067 goto err_out_image_lock;
7068
7069 device_add_disk(&rbd_dev->dev, rbd_dev->disk, NULL);
7070
7071 spin_lock(&rbd_dev_list_lock);
7072 list_add_tail(&rbd_dev->node, &rbd_dev_list);
7073 spin_unlock(&rbd_dev_list_lock);
7074
7075 pr_info("%s: capacity %llu features 0x%llx\n", rbd_dev->disk->disk_name,
7076 (unsigned long long)get_capacity(rbd_dev->disk) << SECTOR_SHIFT,
7077 rbd_dev->header.features);
7078 rc = count;
7079out:
7080 module_put(THIS_MODULE);
7081 return rc;
7082
7083err_out_image_lock:
7084 rbd_dev_image_unlock(rbd_dev);
7085 rbd_dev_device_release(rbd_dev);
7086err_out_image_probe:
7087 rbd_dev_image_release(rbd_dev);
7088err_out_rbd_dev:
7089 rbd_dev_destroy(rbd_dev);
7090err_out_client:
7091 rbd_put_client(rbdc);
7092err_out_args:
7093 rbd_spec_put(spec);
7094 kfree(rbd_opts);
7095 goto out;
7096}
7097
7098static ssize_t add_store(struct bus_type *bus, const char *buf, size_t count)
7099{
7100 if (single_major)
7101 return -EINVAL;
7102
7103 return do_rbd_add(bus, buf, count);
7104}
7105
7106static ssize_t add_single_major_store(struct bus_type *bus, const char *buf,
7107 size_t count)
7108{
7109 return do_rbd_add(bus, buf, count);
7110}
7111
7112static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
7113{
7114 while (rbd_dev->parent) {
7115 struct rbd_device *first = rbd_dev;
7116 struct rbd_device *second = first->parent;
7117 struct rbd_device *third;
7118
7119 /*
7120 * Follow to the parent with no grandparent and
7121 * remove it.
7122 */
7123 while (second && (third = second->parent)) {
7124 first = second;
7125 second = third;
7126 }
7127 rbd_assert(second);
7128 rbd_dev_image_release(second);
7129 rbd_dev_destroy(second);
7130 first->parent = NULL;
7131 first->parent_overlap = 0;
7132
7133 rbd_assert(first->parent_spec);
7134 rbd_spec_put(first->parent_spec);
7135 first->parent_spec = NULL;
7136 }
7137}
7138
7139static ssize_t do_rbd_remove(struct bus_type *bus,
7140 const char *buf,
7141 size_t count)
7142{
7143 struct rbd_device *rbd_dev = NULL;
7144 struct list_head *tmp;
7145 int dev_id;
7146 char opt_buf[6];
7147 bool force = false;
7148 int ret;
7149
7150 if (!capable(CAP_SYS_ADMIN))
7151 return -EPERM;
7152
7153 dev_id = -1;
7154 opt_buf[0] = '\0';
7155 sscanf(buf, "%d %5s", &dev_id, opt_buf);
7156 if (dev_id < 0) {
7157 pr_err("dev_id out of range\n");
7158 return -EINVAL;
7159 }
7160 if (opt_buf[0] != '\0') {
7161 if (!strcmp(opt_buf, "force")) {
7162 force = true;
7163 } else {
7164 pr_err("bad remove option at '%s'\n", opt_buf);
7165 return -EINVAL;
7166 }
7167 }
7168
7169 ret = -ENOENT;
7170 spin_lock(&rbd_dev_list_lock);
7171 list_for_each(tmp, &rbd_dev_list) {
7172 rbd_dev = list_entry(tmp, struct rbd_device, node);
7173 if (rbd_dev->dev_id == dev_id) {
7174 ret = 0;
7175 break;
7176 }
7177 }
7178 if (!ret) {
7179 spin_lock_irq(&rbd_dev->lock);
7180 if (rbd_dev->open_count && !force)
7181 ret = -EBUSY;
7182 else if (test_and_set_bit(RBD_DEV_FLAG_REMOVING,
7183 &rbd_dev->flags))
7184 ret = -EINPROGRESS;
7185 spin_unlock_irq(&rbd_dev->lock);
7186 }
7187 spin_unlock(&rbd_dev_list_lock);
7188 if (ret)
7189 return ret;
7190
7191 if (force) {
7192 /*
7193 * Prevent new IO from being queued and wait for existing
7194 * IO to complete/fail.
7195 */
7196 blk_mq_freeze_queue(rbd_dev->disk->queue);
7197 blk_set_queue_dying(rbd_dev->disk->queue);
7198 }
7199
7200 del_gendisk(rbd_dev->disk);
7201 spin_lock(&rbd_dev_list_lock);
7202 list_del_init(&rbd_dev->node);
7203 spin_unlock(&rbd_dev_list_lock);
7204 device_del(&rbd_dev->dev);
7205
7206 rbd_dev_image_unlock(rbd_dev);
7207 rbd_dev_device_release(rbd_dev);
7208 rbd_dev_image_release(rbd_dev);
7209 rbd_dev_destroy(rbd_dev);
7210 return count;
7211}
7212
7213static ssize_t remove_store(struct bus_type *bus, const char *buf, size_t count)
7214{
7215 if (single_major)
7216 return -EINVAL;
7217
7218 return do_rbd_remove(bus, buf, count);
7219}
7220
7221static ssize_t remove_single_major_store(struct bus_type *bus, const char *buf,
7222 size_t count)
7223{
7224 return do_rbd_remove(bus, buf, count);
7225}
7226
7227/*
7228 * create control files in sysfs
7229 * /sys/bus/rbd/...
7230 */
7231static int __init rbd_sysfs_init(void)
7232{
7233 int ret;
7234
7235 ret = device_register(&rbd_root_dev);
7236 if (ret < 0)
7237 return ret;
7238
7239 ret = bus_register(&rbd_bus_type);
7240 if (ret < 0)
7241 device_unregister(&rbd_root_dev);
7242
7243 return ret;
7244}
7245
7246static void __exit rbd_sysfs_cleanup(void)
7247{
7248 bus_unregister(&rbd_bus_type);
7249 device_unregister(&rbd_root_dev);
7250}
7251
7252static int __init rbd_slab_init(void)
7253{
7254 rbd_assert(!rbd_img_request_cache);
7255 rbd_img_request_cache = KMEM_CACHE(rbd_img_request, 0);
7256 if (!rbd_img_request_cache)
7257 return -ENOMEM;
7258
7259 rbd_assert(!rbd_obj_request_cache);
7260 rbd_obj_request_cache = KMEM_CACHE(rbd_obj_request, 0);
7261 if (!rbd_obj_request_cache)
7262 goto out_err;
7263
7264 return 0;
7265
7266out_err:
7267 kmem_cache_destroy(rbd_img_request_cache);
7268 rbd_img_request_cache = NULL;
7269 return -ENOMEM;
7270}
7271
7272static void rbd_slab_exit(void)
7273{
7274 rbd_assert(rbd_obj_request_cache);
7275 kmem_cache_destroy(rbd_obj_request_cache);
7276 rbd_obj_request_cache = NULL;
7277
7278 rbd_assert(rbd_img_request_cache);
7279 kmem_cache_destroy(rbd_img_request_cache);
7280 rbd_img_request_cache = NULL;
7281}
7282
7283static int __init rbd_init(void)
7284{
7285 int rc;
7286
7287 if (!libceph_compatible(NULL)) {
7288 rbd_warn(NULL, "libceph incompatibility (quitting)");
7289 return -EINVAL;
7290 }
7291
7292 rc = rbd_slab_init();
7293 if (rc)
7294 return rc;
7295
7296 /*
7297 * The number of active work items is limited by the number of
7298 * rbd devices * queue depth, so leave @max_active at default.
7299 */
7300 rbd_wq = alloc_workqueue(RBD_DRV_NAME, WQ_MEM_RECLAIM, 0);
7301 if (!rbd_wq) {
7302 rc = -ENOMEM;
7303 goto err_out_slab;
7304 }
7305
7306 if (single_major) {
7307 rbd_major = register_blkdev(0, RBD_DRV_NAME);
7308 if (rbd_major < 0) {
7309 rc = rbd_major;
7310 goto err_out_wq;
7311 }
7312 }
7313
7314 rc = rbd_sysfs_init();
7315 if (rc)
7316 goto err_out_blkdev;
7317
7318 if (single_major)
7319 pr_info("loaded (major %d)\n", rbd_major);
7320 else
7321 pr_info("loaded\n");
7322
7323 return 0;
7324
7325err_out_blkdev:
7326 if (single_major)
7327 unregister_blkdev(rbd_major, RBD_DRV_NAME);
7328err_out_wq:
7329 destroy_workqueue(rbd_wq);
7330err_out_slab:
7331 rbd_slab_exit();
7332 return rc;
7333}
7334
7335static void __exit rbd_exit(void)
7336{
7337 ida_destroy(&rbd_dev_id_ida);
7338 rbd_sysfs_cleanup();
7339 if (single_major)
7340 unregister_blkdev(rbd_major, RBD_DRV_NAME);
7341 destroy_workqueue(rbd_wq);
7342 rbd_slab_exit();
7343}
7344
7345module_init(rbd_init);
7346module_exit(rbd_exit);
7347
7348MODULE_AUTHOR("Alex Elder <elder@inktank.com>");
7349MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
7350MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
7351/* following authorship retained from original osdblk.c */
7352MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
7353
7354MODULE_DESCRIPTION("RADOS Block Device (RBD) driver");
7355MODULE_LICENSE("GPL");