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Merge tag 'mm-hotfixes-stable-2025-07-11-16-16' of git://git.kernel.org/pub/scm/linux...
[linux-2.6-block.git] / drivers / block / rbd.c
... / ...
CommitLineData
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_QUIESCING,
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 quiescing_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(const struct bus_type *bus, const char *buf, size_t count);
495static ssize_t remove_store(const struct bus_type *bus, const char *buf,
496 size_t count);
497static ssize_t add_single_major_store(const struct bus_type *bus, const char *buf,
498 size_t count);
499static ssize_t remove_single_major_store(const 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_QUIESCING;
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(const 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 const 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,
636 struct rbd_image_header *header);
637static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
638 u64 snap_id);
639static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
640 u8 *order, u64 *snap_size);
641static int rbd_dev_v2_get_flags(struct rbd_device *rbd_dev);
642
643static void rbd_obj_handle_request(struct rbd_obj_request *obj_req, int result);
644static void rbd_img_handle_request(struct rbd_img_request *img_req, int result);
645
646/*
647 * Return true if nothing else is pending.
648 */
649static bool pending_result_dec(struct pending_result *pending, int *result)
650{
651 rbd_assert(pending->num_pending > 0);
652
653 if (*result && !pending->result)
654 pending->result = *result;
655 if (--pending->num_pending)
656 return false;
657
658 *result = pending->result;
659 return true;
660}
661
662static int rbd_open(struct gendisk *disk, blk_mode_t mode)
663{
664 struct rbd_device *rbd_dev = disk->private_data;
665 bool removing = false;
666
667 spin_lock_irq(&rbd_dev->lock);
668 if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags))
669 removing = true;
670 else
671 rbd_dev->open_count++;
672 spin_unlock_irq(&rbd_dev->lock);
673 if (removing)
674 return -ENOENT;
675
676 (void) get_device(&rbd_dev->dev);
677
678 return 0;
679}
680
681static void rbd_release(struct gendisk *disk)
682{
683 struct rbd_device *rbd_dev = disk->private_data;
684 unsigned long open_count_before;
685
686 spin_lock_irq(&rbd_dev->lock);
687 open_count_before = rbd_dev->open_count--;
688 spin_unlock_irq(&rbd_dev->lock);
689 rbd_assert(open_count_before > 0);
690
691 put_device(&rbd_dev->dev);
692}
693
694static const struct block_device_operations rbd_bd_ops = {
695 .owner = THIS_MODULE,
696 .open = rbd_open,
697 .release = rbd_release,
698};
699
700/*
701 * Initialize an rbd client instance. Success or not, this function
702 * consumes ceph_opts. Caller holds client_mutex.
703 */
704static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
705{
706 struct rbd_client *rbdc;
707 int ret = -ENOMEM;
708
709 dout("%s:\n", __func__);
710 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
711 if (!rbdc)
712 goto out_opt;
713
714 kref_init(&rbdc->kref);
715 INIT_LIST_HEAD(&rbdc->node);
716
717 rbdc->client = ceph_create_client(ceph_opts, rbdc);
718 if (IS_ERR(rbdc->client))
719 goto out_rbdc;
720 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
721
722 ret = ceph_open_session(rbdc->client);
723 if (ret < 0)
724 goto out_client;
725
726 spin_lock(&rbd_client_list_lock);
727 list_add_tail(&rbdc->node, &rbd_client_list);
728 spin_unlock(&rbd_client_list_lock);
729
730 dout("%s: rbdc %p\n", __func__, rbdc);
731
732 return rbdc;
733out_client:
734 ceph_destroy_client(rbdc->client);
735out_rbdc:
736 kfree(rbdc);
737out_opt:
738 if (ceph_opts)
739 ceph_destroy_options(ceph_opts);
740 dout("%s: error %d\n", __func__, ret);
741
742 return ERR_PTR(ret);
743}
744
745static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
746{
747 kref_get(&rbdc->kref);
748
749 return rbdc;
750}
751
752/*
753 * Find a ceph client with specific addr and configuration. If
754 * found, bump its reference count.
755 */
756static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
757{
758 struct rbd_client *rbdc = NULL, *iter;
759
760 if (ceph_opts->flags & CEPH_OPT_NOSHARE)
761 return NULL;
762
763 spin_lock(&rbd_client_list_lock);
764 list_for_each_entry(iter, &rbd_client_list, node) {
765 if (!ceph_compare_options(ceph_opts, iter->client)) {
766 __rbd_get_client(iter);
767
768 rbdc = iter;
769 break;
770 }
771 }
772 spin_unlock(&rbd_client_list_lock);
773
774 return rbdc;
775}
776
777/*
778 * (Per device) rbd map options
779 */
780enum {
781 Opt_queue_depth,
782 Opt_alloc_size,
783 Opt_lock_timeout,
784 /* int args above */
785 Opt_pool_ns,
786 Opt_compression_hint,
787 /* string args above */
788 Opt_read_only,
789 Opt_read_write,
790 Opt_lock_on_read,
791 Opt_exclusive,
792 Opt_notrim,
793};
794
795enum {
796 Opt_compression_hint_none,
797 Opt_compression_hint_compressible,
798 Opt_compression_hint_incompressible,
799};
800
801static const struct constant_table rbd_param_compression_hint[] = {
802 {"none", Opt_compression_hint_none},
803 {"compressible", Opt_compression_hint_compressible},
804 {"incompressible", Opt_compression_hint_incompressible},
805 {}
806};
807
808static const struct fs_parameter_spec rbd_parameters[] = {
809 fsparam_u32 ("alloc_size", Opt_alloc_size),
810 fsparam_enum ("compression_hint", Opt_compression_hint,
811 rbd_param_compression_hint),
812 fsparam_flag ("exclusive", Opt_exclusive),
813 fsparam_flag ("lock_on_read", Opt_lock_on_read),
814 fsparam_u32 ("lock_timeout", Opt_lock_timeout),
815 fsparam_flag ("notrim", Opt_notrim),
816 fsparam_string ("_pool_ns", Opt_pool_ns),
817 fsparam_u32 ("queue_depth", Opt_queue_depth),
818 fsparam_flag ("read_only", Opt_read_only),
819 fsparam_flag ("read_write", Opt_read_write),
820 fsparam_flag ("ro", Opt_read_only),
821 fsparam_flag ("rw", Opt_read_write),
822 {}
823};
824
825struct rbd_options {
826 int queue_depth;
827 int alloc_size;
828 unsigned long lock_timeout;
829 bool read_only;
830 bool lock_on_read;
831 bool exclusive;
832 bool trim;
833
834 u32 alloc_hint_flags; /* CEPH_OSD_OP_ALLOC_HINT_FLAG_* */
835};
836
837#define RBD_QUEUE_DEPTH_DEFAULT BLKDEV_DEFAULT_RQ
838#define RBD_ALLOC_SIZE_DEFAULT (64 * 1024)
839#define RBD_LOCK_TIMEOUT_DEFAULT 0 /* no timeout */
840#define RBD_READ_ONLY_DEFAULT false
841#define RBD_LOCK_ON_READ_DEFAULT false
842#define RBD_EXCLUSIVE_DEFAULT false
843#define RBD_TRIM_DEFAULT true
844
845struct rbd_parse_opts_ctx {
846 struct rbd_spec *spec;
847 struct ceph_options *copts;
848 struct rbd_options *opts;
849};
850
851static char* obj_op_name(enum obj_operation_type op_type)
852{
853 switch (op_type) {
854 case OBJ_OP_READ:
855 return "read";
856 case OBJ_OP_WRITE:
857 return "write";
858 case OBJ_OP_DISCARD:
859 return "discard";
860 case OBJ_OP_ZEROOUT:
861 return "zeroout";
862 default:
863 return "???";
864 }
865}
866
867/*
868 * Destroy ceph client
869 *
870 * Caller must hold rbd_client_list_lock.
871 */
872static void rbd_client_release(struct kref *kref)
873{
874 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
875
876 dout("%s: rbdc %p\n", __func__, rbdc);
877 spin_lock(&rbd_client_list_lock);
878 list_del(&rbdc->node);
879 spin_unlock(&rbd_client_list_lock);
880
881 ceph_destroy_client(rbdc->client);
882 kfree(rbdc);
883}
884
885/*
886 * Drop reference to ceph client node. If it's not referenced anymore, release
887 * it.
888 */
889static void rbd_put_client(struct rbd_client *rbdc)
890{
891 if (rbdc)
892 kref_put(&rbdc->kref, rbd_client_release);
893}
894
895/*
896 * Get a ceph client with specific addr and configuration, if one does
897 * not exist create it. Either way, ceph_opts is consumed by this
898 * function.
899 */
900static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
901{
902 struct rbd_client *rbdc;
903 int ret;
904
905 mutex_lock(&client_mutex);
906 rbdc = rbd_client_find(ceph_opts);
907 if (rbdc) {
908 ceph_destroy_options(ceph_opts);
909
910 /*
911 * Using an existing client. Make sure ->pg_pools is up to
912 * date before we look up the pool id in do_rbd_add().
913 */
914 ret = ceph_wait_for_latest_osdmap(rbdc->client,
915 rbdc->client->options->mount_timeout);
916 if (ret) {
917 rbd_warn(NULL, "failed to get latest osdmap: %d", ret);
918 rbd_put_client(rbdc);
919 rbdc = ERR_PTR(ret);
920 }
921 } else {
922 rbdc = rbd_client_create(ceph_opts);
923 }
924 mutex_unlock(&client_mutex);
925
926 return rbdc;
927}
928
929static bool rbd_image_format_valid(u32 image_format)
930{
931 return image_format == 1 || image_format == 2;
932}
933
934static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
935{
936 size_t size;
937 u32 snap_count;
938
939 /* The header has to start with the magic rbd header text */
940 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
941 return false;
942
943 /* The bio layer requires at least sector-sized I/O */
944
945 if (ondisk->options.order < SECTOR_SHIFT)
946 return false;
947
948 /* If we use u64 in a few spots we may be able to loosen this */
949
950 if (ondisk->options.order > 8 * sizeof (int) - 1)
951 return false;
952
953 /*
954 * The size of a snapshot header has to fit in a size_t, and
955 * that limits the number of snapshots.
956 */
957 snap_count = le32_to_cpu(ondisk->snap_count);
958 size = SIZE_MAX - sizeof (struct ceph_snap_context);
959 if (snap_count > size / sizeof (__le64))
960 return false;
961
962 /*
963 * Not only that, but the size of the entire the snapshot
964 * header must also be representable in a size_t.
965 */
966 size -= snap_count * sizeof (__le64);
967 if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
968 return false;
969
970 return true;
971}
972
973/*
974 * returns the size of an object in the image
975 */
976static u32 rbd_obj_bytes(struct rbd_image_header *header)
977{
978 return 1U << header->obj_order;
979}
980
981static void rbd_init_layout(struct rbd_device *rbd_dev)
982{
983 if (rbd_dev->header.stripe_unit == 0 ||
984 rbd_dev->header.stripe_count == 0) {
985 rbd_dev->header.stripe_unit = rbd_obj_bytes(&rbd_dev->header);
986 rbd_dev->header.stripe_count = 1;
987 }
988
989 rbd_dev->layout.stripe_unit = rbd_dev->header.stripe_unit;
990 rbd_dev->layout.stripe_count = rbd_dev->header.stripe_count;
991 rbd_dev->layout.object_size = rbd_obj_bytes(&rbd_dev->header);
992 rbd_dev->layout.pool_id = rbd_dev->header.data_pool_id == CEPH_NOPOOL ?
993 rbd_dev->spec->pool_id : rbd_dev->header.data_pool_id;
994 RCU_INIT_POINTER(rbd_dev->layout.pool_ns, NULL);
995}
996
997static void rbd_image_header_cleanup(struct rbd_image_header *header)
998{
999 kfree(header->object_prefix);
1000 ceph_put_snap_context(header->snapc);
1001 kfree(header->snap_sizes);
1002 kfree(header->snap_names);
1003
1004 memset(header, 0, sizeof(*header));
1005}
1006
1007/*
1008 * Fill an rbd image header with information from the given format 1
1009 * on-disk header.
1010 */
1011static int rbd_header_from_disk(struct rbd_image_header *header,
1012 struct rbd_image_header_ondisk *ondisk,
1013 bool first_time)
1014{
1015 struct ceph_snap_context *snapc;
1016 char *object_prefix = NULL;
1017 char *snap_names = NULL;
1018 u64 *snap_sizes = NULL;
1019 u32 snap_count;
1020 int ret = -ENOMEM;
1021 u32 i;
1022
1023 /* Allocate this now to avoid having to handle failure below */
1024
1025 if (first_time) {
1026 object_prefix = kstrndup(ondisk->object_prefix,
1027 sizeof(ondisk->object_prefix),
1028 GFP_KERNEL);
1029 if (!object_prefix)
1030 return -ENOMEM;
1031 }
1032
1033 /* Allocate the snapshot context and fill it in */
1034
1035 snap_count = le32_to_cpu(ondisk->snap_count);
1036 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
1037 if (!snapc)
1038 goto out_err;
1039 snapc->seq = le64_to_cpu(ondisk->snap_seq);
1040 if (snap_count) {
1041 struct rbd_image_snap_ondisk *snaps;
1042 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);
1043
1044 /* We'll keep a copy of the snapshot names... */
1045
1046 if (snap_names_len > (u64)SIZE_MAX)
1047 goto out_2big;
1048 snap_names = kmalloc(snap_names_len, GFP_KERNEL);
1049 if (!snap_names)
1050 goto out_err;
1051
1052 /* ...as well as the array of their sizes. */
1053 snap_sizes = kmalloc_array(snap_count,
1054 sizeof(*header->snap_sizes),
1055 GFP_KERNEL);
1056 if (!snap_sizes)
1057 goto out_err;
1058
1059 /*
1060 * Copy the names, and fill in each snapshot's id
1061 * and size.
1062 *
1063 * Note that rbd_dev_v1_header_info() guarantees the
1064 * ondisk buffer we're working with has
1065 * snap_names_len bytes beyond the end of the
1066 * snapshot id array, this memcpy() is safe.
1067 */
1068 memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len);
1069 snaps = ondisk->snaps;
1070 for (i = 0; i < snap_count; i++) {
1071 snapc->snaps[i] = le64_to_cpu(snaps[i].id);
1072 snap_sizes[i] = le64_to_cpu(snaps[i].image_size);
1073 }
1074 }
1075
1076 /* We won't fail any more, fill in the header */
1077
1078 if (first_time) {
1079 header->object_prefix = object_prefix;
1080 header->obj_order = ondisk->options.order;
1081 }
1082
1083 /* The remaining fields always get updated (when we refresh) */
1084
1085 header->image_size = le64_to_cpu(ondisk->image_size);
1086 header->snapc = snapc;
1087 header->snap_names = snap_names;
1088 header->snap_sizes = snap_sizes;
1089
1090 return 0;
1091out_2big:
1092 ret = -EIO;
1093out_err:
1094 kfree(snap_sizes);
1095 kfree(snap_names);
1096 ceph_put_snap_context(snapc);
1097 kfree(object_prefix);
1098
1099 return ret;
1100}
1101
1102static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
1103{
1104 const char *snap_name;
1105
1106 rbd_assert(which < rbd_dev->header.snapc->num_snaps);
1107
1108 /* Skip over names until we find the one we are looking for */
1109
1110 snap_name = rbd_dev->header.snap_names;
1111 while (which--)
1112 snap_name += strlen(snap_name) + 1;
1113
1114 return kstrdup(snap_name, GFP_KERNEL);
1115}
1116
1117/*
1118 * Snapshot id comparison function for use with qsort()/bsearch().
1119 * Note that result is for snapshots in *descending* order.
1120 */
1121static int snapid_compare_reverse(const void *s1, const void *s2)
1122{
1123 u64 snap_id1 = *(u64 *)s1;
1124 u64 snap_id2 = *(u64 *)s2;
1125
1126 if (snap_id1 < snap_id2)
1127 return 1;
1128 return snap_id1 == snap_id2 ? 0 : -1;
1129}
1130
1131/*
1132 * Search a snapshot context to see if the given snapshot id is
1133 * present.
1134 *
1135 * Returns the position of the snapshot id in the array if it's found,
1136 * or BAD_SNAP_INDEX otherwise.
1137 *
1138 * Note: The snapshot array is in kept sorted (by the osd) in
1139 * reverse order, highest snapshot id first.
1140 */
1141static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id)
1142{
1143 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
1144 u64 *found;
1145
1146 found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps,
1147 sizeof (snap_id), snapid_compare_reverse);
1148
1149 return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX;
1150}
1151
1152static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
1153 u64 snap_id)
1154{
1155 u32 which;
1156 const char *snap_name;
1157
1158 which = rbd_dev_snap_index(rbd_dev, snap_id);
1159 if (which == BAD_SNAP_INDEX)
1160 return ERR_PTR(-ENOENT);
1161
1162 snap_name = _rbd_dev_v1_snap_name(rbd_dev, which);
1163 return snap_name ? snap_name : ERR_PTR(-ENOMEM);
1164}
1165
1166static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
1167{
1168 if (snap_id == CEPH_NOSNAP)
1169 return RBD_SNAP_HEAD_NAME;
1170
1171 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1172 if (rbd_dev->image_format == 1)
1173 return rbd_dev_v1_snap_name(rbd_dev, snap_id);
1174
1175 return rbd_dev_v2_snap_name(rbd_dev, snap_id);
1176}
1177
1178static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
1179 u64 *snap_size)
1180{
1181 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1182 if (snap_id == CEPH_NOSNAP) {
1183 *snap_size = rbd_dev->header.image_size;
1184 } else if (rbd_dev->image_format == 1) {
1185 u32 which;
1186
1187 which = rbd_dev_snap_index(rbd_dev, snap_id);
1188 if (which == BAD_SNAP_INDEX)
1189 return -ENOENT;
1190
1191 *snap_size = rbd_dev->header.snap_sizes[which];
1192 } else {
1193 u64 size = 0;
1194 int ret;
1195
1196 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
1197 if (ret)
1198 return ret;
1199
1200 *snap_size = size;
1201 }
1202 return 0;
1203}
1204
1205static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
1206{
1207 u64 snap_id = rbd_dev->spec->snap_id;
1208 u64 size = 0;
1209 int ret;
1210
1211 ret = rbd_snap_size(rbd_dev, snap_id, &size);
1212 if (ret)
1213 return ret;
1214
1215 rbd_dev->mapping.size = size;
1216 return 0;
1217}
1218
1219static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
1220{
1221 rbd_dev->mapping.size = 0;
1222}
1223
1224static void zero_bios(struct ceph_bio_iter *bio_pos, u32 off, u32 bytes)
1225{
1226 struct ceph_bio_iter it = *bio_pos;
1227
1228 ceph_bio_iter_advance(&it, off);
1229 ceph_bio_iter_advance_step(&it, bytes, ({
1230 memzero_bvec(&bv);
1231 }));
1232}
1233
1234static void zero_bvecs(struct ceph_bvec_iter *bvec_pos, u32 off, u32 bytes)
1235{
1236 struct ceph_bvec_iter it = *bvec_pos;
1237
1238 ceph_bvec_iter_advance(&it, off);
1239 ceph_bvec_iter_advance_step(&it, bytes, ({
1240 memzero_bvec(&bv);
1241 }));
1242}
1243
1244/*
1245 * Zero a range in @obj_req data buffer defined by a bio (list) or
1246 * (private) bio_vec array.
1247 *
1248 * @off is relative to the start of the data buffer.
1249 */
1250static void rbd_obj_zero_range(struct rbd_obj_request *obj_req, u32 off,
1251 u32 bytes)
1252{
1253 dout("%s %p data buf %u~%u\n", __func__, obj_req, off, bytes);
1254
1255 switch (obj_req->img_request->data_type) {
1256 case OBJ_REQUEST_BIO:
1257 zero_bios(&obj_req->bio_pos, off, bytes);
1258 break;
1259 case OBJ_REQUEST_BVECS:
1260 case OBJ_REQUEST_OWN_BVECS:
1261 zero_bvecs(&obj_req->bvec_pos, off, bytes);
1262 break;
1263 default:
1264 BUG();
1265 }
1266}
1267
1268static void rbd_obj_request_destroy(struct kref *kref);
1269static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
1270{
1271 rbd_assert(obj_request != NULL);
1272 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1273 kref_read(&obj_request->kref));
1274 kref_put(&obj_request->kref, rbd_obj_request_destroy);
1275}
1276
1277static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
1278 struct rbd_obj_request *obj_request)
1279{
1280 rbd_assert(obj_request->img_request == NULL);
1281
1282 /* Image request now owns object's original reference */
1283 obj_request->img_request = img_request;
1284 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
1285}
1286
1287static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
1288 struct rbd_obj_request *obj_request)
1289{
1290 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
1291 list_del(&obj_request->ex.oe_item);
1292 rbd_assert(obj_request->img_request == img_request);
1293 rbd_obj_request_put(obj_request);
1294}
1295
1296static void rbd_osd_submit(struct ceph_osd_request *osd_req)
1297{
1298 struct rbd_obj_request *obj_req = osd_req->r_priv;
1299
1300 dout("%s osd_req %p for obj_req %p objno %llu %llu~%llu\n",
1301 __func__, osd_req, obj_req, obj_req->ex.oe_objno,
1302 obj_req->ex.oe_off, obj_req->ex.oe_len);
1303 ceph_osdc_start_request(osd_req->r_osdc, osd_req);
1304}
1305
1306/*
1307 * The default/initial value for all image request flags is 0. Each
1308 * is conditionally set to 1 at image request initialization time
1309 * and currently never change thereafter.
1310 */
1311static void img_request_layered_set(struct rbd_img_request *img_request)
1312{
1313 set_bit(IMG_REQ_LAYERED, &img_request->flags);
1314}
1315
1316static bool img_request_layered_test(struct rbd_img_request *img_request)
1317{
1318 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
1319}
1320
1321static bool rbd_obj_is_entire(struct rbd_obj_request *obj_req)
1322{
1323 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1324
1325 return !obj_req->ex.oe_off &&
1326 obj_req->ex.oe_len == rbd_dev->layout.object_size;
1327}
1328
1329static bool rbd_obj_is_tail(struct rbd_obj_request *obj_req)
1330{
1331 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1332
1333 return obj_req->ex.oe_off + obj_req->ex.oe_len ==
1334 rbd_dev->layout.object_size;
1335}
1336
1337/*
1338 * Must be called after rbd_obj_calc_img_extents().
1339 */
1340static void rbd_obj_set_copyup_enabled(struct rbd_obj_request *obj_req)
1341{
1342 rbd_assert(obj_req->img_request->snapc);
1343
1344 if (obj_req->img_request->op_type == OBJ_OP_DISCARD) {
1345 dout("%s %p objno %llu discard\n", __func__, obj_req,
1346 obj_req->ex.oe_objno);
1347 return;
1348 }
1349
1350 if (!obj_req->num_img_extents) {
1351 dout("%s %p objno %llu not overlapping\n", __func__, obj_req,
1352 obj_req->ex.oe_objno);
1353 return;
1354 }
1355
1356 if (rbd_obj_is_entire(obj_req) &&
1357 !obj_req->img_request->snapc->num_snaps) {
1358 dout("%s %p objno %llu entire\n", __func__, obj_req,
1359 obj_req->ex.oe_objno);
1360 return;
1361 }
1362
1363 obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ENABLED;
1364}
1365
1366static u64 rbd_obj_img_extents_bytes(struct rbd_obj_request *obj_req)
1367{
1368 return ceph_file_extents_bytes(obj_req->img_extents,
1369 obj_req->num_img_extents);
1370}
1371
1372static bool rbd_img_is_write(struct rbd_img_request *img_req)
1373{
1374 switch (img_req->op_type) {
1375 case OBJ_OP_READ:
1376 return false;
1377 case OBJ_OP_WRITE:
1378 case OBJ_OP_DISCARD:
1379 case OBJ_OP_ZEROOUT:
1380 return true;
1381 default:
1382 BUG();
1383 }
1384}
1385
1386static void rbd_osd_req_callback(struct ceph_osd_request *osd_req)
1387{
1388 struct rbd_obj_request *obj_req = osd_req->r_priv;
1389 int result;
1390
1391 dout("%s osd_req %p result %d for obj_req %p\n", __func__, osd_req,
1392 osd_req->r_result, obj_req);
1393
1394 /*
1395 * Writes aren't allowed to return a data payload. In some
1396 * guarded write cases (e.g. stat + zero on an empty object)
1397 * a stat response makes it through, but we don't care.
1398 */
1399 if (osd_req->r_result > 0 && rbd_img_is_write(obj_req->img_request))
1400 result = 0;
1401 else
1402 result = osd_req->r_result;
1403
1404 rbd_obj_handle_request(obj_req, result);
1405}
1406
1407static void rbd_osd_format_read(struct ceph_osd_request *osd_req)
1408{
1409 struct rbd_obj_request *obj_request = osd_req->r_priv;
1410 struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev;
1411 struct ceph_options *opt = rbd_dev->rbd_client->client->options;
1412
1413 osd_req->r_flags = CEPH_OSD_FLAG_READ | opt->read_from_replica;
1414 osd_req->r_snapid = obj_request->img_request->snap_id;
1415}
1416
1417static void rbd_osd_format_write(struct ceph_osd_request *osd_req)
1418{
1419 struct rbd_obj_request *obj_request = osd_req->r_priv;
1420
1421 osd_req->r_flags = CEPH_OSD_FLAG_WRITE;
1422 ktime_get_real_ts64(&osd_req->r_mtime);
1423 osd_req->r_data_offset = obj_request->ex.oe_off;
1424}
1425
1426static struct ceph_osd_request *
1427__rbd_obj_add_osd_request(struct rbd_obj_request *obj_req,
1428 struct ceph_snap_context *snapc, int num_ops)
1429{
1430 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1431 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1432 struct ceph_osd_request *req;
1433 const char *name_format = rbd_dev->image_format == 1 ?
1434 RBD_V1_DATA_FORMAT : RBD_V2_DATA_FORMAT;
1435 int ret;
1436
1437 req = ceph_osdc_alloc_request(osdc, snapc, num_ops, false, GFP_NOIO);
1438 if (!req)
1439 return ERR_PTR(-ENOMEM);
1440
1441 list_add_tail(&req->r_private_item, &obj_req->osd_reqs);
1442 req->r_callback = rbd_osd_req_callback;
1443 req->r_priv = obj_req;
1444
1445 /*
1446 * Data objects may be stored in a separate pool, but always in
1447 * the same namespace in that pool as the header in its pool.
1448 */
1449 ceph_oloc_copy(&req->r_base_oloc, &rbd_dev->header_oloc);
1450 req->r_base_oloc.pool = rbd_dev->layout.pool_id;
1451
1452 ret = ceph_oid_aprintf(&req->r_base_oid, GFP_NOIO, name_format,
1453 rbd_dev->header.object_prefix,
1454 obj_req->ex.oe_objno);
1455 if (ret)
1456 return ERR_PTR(ret);
1457
1458 return req;
1459}
1460
1461static struct ceph_osd_request *
1462rbd_obj_add_osd_request(struct rbd_obj_request *obj_req, int num_ops)
1463{
1464 rbd_assert(obj_req->img_request->snapc);
1465 return __rbd_obj_add_osd_request(obj_req, obj_req->img_request->snapc,
1466 num_ops);
1467}
1468
1469static struct rbd_obj_request *rbd_obj_request_create(void)
1470{
1471 struct rbd_obj_request *obj_request;
1472
1473 obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_NOIO);
1474 if (!obj_request)
1475 return NULL;
1476
1477 ceph_object_extent_init(&obj_request->ex);
1478 INIT_LIST_HEAD(&obj_request->osd_reqs);
1479 mutex_init(&obj_request->state_mutex);
1480 kref_init(&obj_request->kref);
1481
1482 dout("%s %p\n", __func__, obj_request);
1483 return obj_request;
1484}
1485
1486static void rbd_obj_request_destroy(struct kref *kref)
1487{
1488 struct rbd_obj_request *obj_request;
1489 struct ceph_osd_request *osd_req;
1490 u32 i;
1491
1492 obj_request = container_of(kref, struct rbd_obj_request, kref);
1493
1494 dout("%s: obj %p\n", __func__, obj_request);
1495
1496 while (!list_empty(&obj_request->osd_reqs)) {
1497 osd_req = list_first_entry(&obj_request->osd_reqs,
1498 struct ceph_osd_request, r_private_item);
1499 list_del_init(&osd_req->r_private_item);
1500 ceph_osdc_put_request(osd_req);
1501 }
1502
1503 switch (obj_request->img_request->data_type) {
1504 case OBJ_REQUEST_NODATA:
1505 case OBJ_REQUEST_BIO:
1506 case OBJ_REQUEST_BVECS:
1507 break; /* Nothing to do */
1508 case OBJ_REQUEST_OWN_BVECS:
1509 kfree(obj_request->bvec_pos.bvecs);
1510 break;
1511 default:
1512 BUG();
1513 }
1514
1515 kfree(obj_request->img_extents);
1516 if (obj_request->copyup_bvecs) {
1517 for (i = 0; i < obj_request->copyup_bvec_count; i++) {
1518 if (obj_request->copyup_bvecs[i].bv_page)
1519 __free_page(obj_request->copyup_bvecs[i].bv_page);
1520 }
1521 kfree(obj_request->copyup_bvecs);
1522 }
1523
1524 kmem_cache_free(rbd_obj_request_cache, obj_request);
1525}
1526
1527/* It's OK to call this for a device with no parent */
1528
1529static void rbd_spec_put(struct rbd_spec *spec);
1530static void rbd_dev_unparent(struct rbd_device *rbd_dev)
1531{
1532 rbd_dev_remove_parent(rbd_dev);
1533 rbd_spec_put(rbd_dev->parent_spec);
1534 rbd_dev->parent_spec = NULL;
1535 rbd_dev->parent_overlap = 0;
1536}
1537
1538/*
1539 * Parent image reference counting is used to determine when an
1540 * image's parent fields can be safely torn down--after there are no
1541 * more in-flight requests to the parent image. When the last
1542 * reference is dropped, cleaning them up is safe.
1543 */
1544static void rbd_dev_parent_put(struct rbd_device *rbd_dev)
1545{
1546 int counter;
1547
1548 if (!rbd_dev->parent_spec)
1549 return;
1550
1551 counter = atomic_dec_return_safe(&rbd_dev->parent_ref);
1552 if (counter > 0)
1553 return;
1554
1555 /* Last reference; clean up parent data structures */
1556
1557 if (!counter)
1558 rbd_dev_unparent(rbd_dev);
1559 else
1560 rbd_warn(rbd_dev, "parent reference underflow");
1561}
1562
1563/*
1564 * If an image has a non-zero parent overlap, get a reference to its
1565 * parent.
1566 *
1567 * Returns true if the rbd device has a parent with a non-zero
1568 * overlap and a reference for it was successfully taken, or
1569 * false otherwise.
1570 */
1571static bool rbd_dev_parent_get(struct rbd_device *rbd_dev)
1572{
1573 int counter = 0;
1574
1575 if (!rbd_dev->parent_spec)
1576 return false;
1577
1578 if (rbd_dev->parent_overlap)
1579 counter = atomic_inc_return_safe(&rbd_dev->parent_ref);
1580
1581 if (counter < 0)
1582 rbd_warn(rbd_dev, "parent reference overflow");
1583
1584 return counter > 0;
1585}
1586
1587static void rbd_img_request_init(struct rbd_img_request *img_request,
1588 struct rbd_device *rbd_dev,
1589 enum obj_operation_type op_type)
1590{
1591 memset(img_request, 0, sizeof(*img_request));
1592
1593 img_request->rbd_dev = rbd_dev;
1594 img_request->op_type = op_type;
1595
1596 INIT_LIST_HEAD(&img_request->lock_item);
1597 INIT_LIST_HEAD(&img_request->object_extents);
1598 mutex_init(&img_request->state_mutex);
1599}
1600
1601/*
1602 * Only snap_id is captured here, for reads. For writes, snapshot
1603 * context is captured in rbd_img_object_requests() after exclusive
1604 * lock is ensured to be held.
1605 */
1606static void rbd_img_capture_header(struct rbd_img_request *img_req)
1607{
1608 struct rbd_device *rbd_dev = img_req->rbd_dev;
1609
1610 lockdep_assert_held(&rbd_dev->header_rwsem);
1611
1612 if (!rbd_img_is_write(img_req))
1613 img_req->snap_id = rbd_dev->spec->snap_id;
1614
1615 if (rbd_dev_parent_get(rbd_dev))
1616 img_request_layered_set(img_req);
1617}
1618
1619static void rbd_img_request_destroy(struct rbd_img_request *img_request)
1620{
1621 struct rbd_obj_request *obj_request;
1622 struct rbd_obj_request *next_obj_request;
1623
1624 dout("%s: img %p\n", __func__, img_request);
1625
1626 WARN_ON(!list_empty(&img_request->lock_item));
1627 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
1628 rbd_img_obj_request_del(img_request, obj_request);
1629
1630 if (img_request_layered_test(img_request))
1631 rbd_dev_parent_put(img_request->rbd_dev);
1632
1633 if (rbd_img_is_write(img_request))
1634 ceph_put_snap_context(img_request->snapc);
1635
1636 if (test_bit(IMG_REQ_CHILD, &img_request->flags))
1637 kmem_cache_free(rbd_img_request_cache, img_request);
1638}
1639
1640#define BITS_PER_OBJ 2
1641#define OBJS_PER_BYTE (BITS_PER_BYTE / BITS_PER_OBJ)
1642#define OBJ_MASK ((1 << BITS_PER_OBJ) - 1)
1643
1644static void __rbd_object_map_index(struct rbd_device *rbd_dev, u64 objno,
1645 u64 *index, u8 *shift)
1646{
1647 u32 off;
1648
1649 rbd_assert(objno < rbd_dev->object_map_size);
1650 *index = div_u64_rem(objno, OBJS_PER_BYTE, &off);
1651 *shift = (OBJS_PER_BYTE - off - 1) * BITS_PER_OBJ;
1652}
1653
1654static u8 __rbd_object_map_get(struct rbd_device *rbd_dev, u64 objno)
1655{
1656 u64 index;
1657 u8 shift;
1658
1659 lockdep_assert_held(&rbd_dev->object_map_lock);
1660 __rbd_object_map_index(rbd_dev, objno, &index, &shift);
1661 return (rbd_dev->object_map[index] >> shift) & OBJ_MASK;
1662}
1663
1664static void __rbd_object_map_set(struct rbd_device *rbd_dev, u64 objno, u8 val)
1665{
1666 u64 index;
1667 u8 shift;
1668 u8 *p;
1669
1670 lockdep_assert_held(&rbd_dev->object_map_lock);
1671 rbd_assert(!(val & ~OBJ_MASK));
1672
1673 __rbd_object_map_index(rbd_dev, objno, &index, &shift);
1674 p = &rbd_dev->object_map[index];
1675 *p = (*p & ~(OBJ_MASK << shift)) | (val << shift);
1676}
1677
1678static u8 rbd_object_map_get(struct rbd_device *rbd_dev, u64 objno)
1679{
1680 u8 state;
1681
1682 spin_lock(&rbd_dev->object_map_lock);
1683 state = __rbd_object_map_get(rbd_dev, objno);
1684 spin_unlock(&rbd_dev->object_map_lock);
1685 return state;
1686}
1687
1688static bool use_object_map(struct rbd_device *rbd_dev)
1689{
1690 /*
1691 * An image mapped read-only can't use the object map -- it isn't
1692 * loaded because the header lock isn't acquired. Someone else can
1693 * write to the image and update the object map behind our back.
1694 *
1695 * A snapshot can't be written to, so using the object map is always
1696 * safe.
1697 */
1698 if (!rbd_is_snap(rbd_dev) && rbd_is_ro(rbd_dev))
1699 return false;
1700
1701 return ((rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP) &&
1702 !(rbd_dev->object_map_flags & RBD_FLAG_OBJECT_MAP_INVALID));
1703}
1704
1705static bool rbd_object_map_may_exist(struct rbd_device *rbd_dev, u64 objno)
1706{
1707 u8 state;
1708
1709 /* fall back to default logic if object map is disabled or invalid */
1710 if (!use_object_map(rbd_dev))
1711 return true;
1712
1713 state = rbd_object_map_get(rbd_dev, objno);
1714 return state != OBJECT_NONEXISTENT;
1715}
1716
1717static void rbd_object_map_name(struct rbd_device *rbd_dev, u64 snap_id,
1718 struct ceph_object_id *oid)
1719{
1720 if (snap_id == CEPH_NOSNAP)
1721 ceph_oid_printf(oid, "%s%s", RBD_OBJECT_MAP_PREFIX,
1722 rbd_dev->spec->image_id);
1723 else
1724 ceph_oid_printf(oid, "%s%s.%016llx", RBD_OBJECT_MAP_PREFIX,
1725 rbd_dev->spec->image_id, snap_id);
1726}
1727
1728static int rbd_object_map_lock(struct rbd_device *rbd_dev)
1729{
1730 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1731 CEPH_DEFINE_OID_ONSTACK(oid);
1732 u8 lock_type;
1733 char *lock_tag;
1734 struct ceph_locker *lockers;
1735 u32 num_lockers;
1736 bool broke_lock = false;
1737 int ret;
1738
1739 rbd_object_map_name(rbd_dev, CEPH_NOSNAP, &oid);
1740
1741again:
1742 ret = ceph_cls_lock(osdc, &oid, &rbd_dev->header_oloc, RBD_LOCK_NAME,
1743 CEPH_CLS_LOCK_EXCLUSIVE, "", "", "", 0);
1744 if (ret != -EBUSY || broke_lock) {
1745 if (ret == -EEXIST)
1746 ret = 0; /* already locked by myself */
1747 if (ret)
1748 rbd_warn(rbd_dev, "failed to lock object map: %d", ret);
1749 return ret;
1750 }
1751
1752 ret = ceph_cls_lock_info(osdc, &oid, &rbd_dev->header_oloc,
1753 RBD_LOCK_NAME, &lock_type, &lock_tag,
1754 &lockers, &num_lockers);
1755 if (ret) {
1756 if (ret == -ENOENT)
1757 goto again;
1758
1759 rbd_warn(rbd_dev, "failed to get object map lockers: %d", ret);
1760 return ret;
1761 }
1762
1763 kfree(lock_tag);
1764 if (num_lockers == 0)
1765 goto again;
1766
1767 rbd_warn(rbd_dev, "breaking object map lock owned by %s%llu",
1768 ENTITY_NAME(lockers[0].id.name));
1769
1770 ret = ceph_cls_break_lock(osdc, &oid, &rbd_dev->header_oloc,
1771 RBD_LOCK_NAME, lockers[0].id.cookie,
1772 &lockers[0].id.name);
1773 ceph_free_lockers(lockers, num_lockers);
1774 if (ret) {
1775 if (ret == -ENOENT)
1776 goto again;
1777
1778 rbd_warn(rbd_dev, "failed to break object map lock: %d", ret);
1779 return ret;
1780 }
1781
1782 broke_lock = true;
1783 goto again;
1784}
1785
1786static void rbd_object_map_unlock(struct rbd_device *rbd_dev)
1787{
1788 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1789 CEPH_DEFINE_OID_ONSTACK(oid);
1790 int ret;
1791
1792 rbd_object_map_name(rbd_dev, CEPH_NOSNAP, &oid);
1793
1794 ret = ceph_cls_unlock(osdc, &oid, &rbd_dev->header_oloc, RBD_LOCK_NAME,
1795 "");
1796 if (ret && ret != -ENOENT)
1797 rbd_warn(rbd_dev, "failed to unlock object map: %d", ret);
1798}
1799
1800static int decode_object_map_header(void **p, void *end, u64 *object_map_size)
1801{
1802 u8 struct_v;
1803 u32 struct_len;
1804 u32 header_len;
1805 void *header_end;
1806 int ret;
1807
1808 ceph_decode_32_safe(p, end, header_len, e_inval);
1809 header_end = *p + header_len;
1810
1811 ret = ceph_start_decoding(p, end, 1, "BitVector header", &struct_v,
1812 &struct_len);
1813 if (ret)
1814 return ret;
1815
1816 ceph_decode_64_safe(p, end, *object_map_size, e_inval);
1817
1818 *p = header_end;
1819 return 0;
1820
1821e_inval:
1822 return -EINVAL;
1823}
1824
1825static int __rbd_object_map_load(struct rbd_device *rbd_dev)
1826{
1827 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1828 CEPH_DEFINE_OID_ONSTACK(oid);
1829 struct page **pages;
1830 void *p, *end;
1831 size_t reply_len;
1832 u64 num_objects;
1833 u64 object_map_bytes;
1834 u64 object_map_size;
1835 int num_pages;
1836 int ret;
1837
1838 rbd_assert(!rbd_dev->object_map && !rbd_dev->object_map_size);
1839
1840 num_objects = ceph_get_num_objects(&rbd_dev->layout,
1841 rbd_dev->mapping.size);
1842 object_map_bytes = DIV_ROUND_UP_ULL(num_objects * BITS_PER_OBJ,
1843 BITS_PER_BYTE);
1844 num_pages = calc_pages_for(0, object_map_bytes) + 1;
1845 pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
1846 if (IS_ERR(pages))
1847 return PTR_ERR(pages);
1848
1849 reply_len = num_pages * PAGE_SIZE;
1850 rbd_object_map_name(rbd_dev, rbd_dev->spec->snap_id, &oid);
1851 ret = ceph_osdc_call(osdc, &oid, &rbd_dev->header_oloc,
1852 "rbd", "object_map_load", CEPH_OSD_FLAG_READ,
1853 NULL, 0, pages, &reply_len);
1854 if (ret)
1855 goto out;
1856
1857 p = page_address(pages[0]);
1858 end = p + min(reply_len, (size_t)PAGE_SIZE);
1859 ret = decode_object_map_header(&p, end, &object_map_size);
1860 if (ret)
1861 goto out;
1862
1863 if (object_map_size != num_objects) {
1864 rbd_warn(rbd_dev, "object map size mismatch: %llu vs %llu",
1865 object_map_size, num_objects);
1866 ret = -EINVAL;
1867 goto out;
1868 }
1869
1870 if (offset_in_page(p) + object_map_bytes > reply_len) {
1871 ret = -EINVAL;
1872 goto out;
1873 }
1874
1875 rbd_dev->object_map = kvmalloc(object_map_bytes, GFP_KERNEL);
1876 if (!rbd_dev->object_map) {
1877 ret = -ENOMEM;
1878 goto out;
1879 }
1880
1881 rbd_dev->object_map_size = object_map_size;
1882 ceph_copy_from_page_vector(pages, rbd_dev->object_map,
1883 offset_in_page(p), object_map_bytes);
1884
1885out:
1886 ceph_release_page_vector(pages, num_pages);
1887 return ret;
1888}
1889
1890static void rbd_object_map_free(struct rbd_device *rbd_dev)
1891{
1892 kvfree(rbd_dev->object_map);
1893 rbd_dev->object_map = NULL;
1894 rbd_dev->object_map_size = 0;
1895}
1896
1897static int rbd_object_map_load(struct rbd_device *rbd_dev)
1898{
1899 int ret;
1900
1901 ret = __rbd_object_map_load(rbd_dev);
1902 if (ret)
1903 return ret;
1904
1905 ret = rbd_dev_v2_get_flags(rbd_dev);
1906 if (ret) {
1907 rbd_object_map_free(rbd_dev);
1908 return ret;
1909 }
1910
1911 if (rbd_dev->object_map_flags & RBD_FLAG_OBJECT_MAP_INVALID)
1912 rbd_warn(rbd_dev, "object map is invalid");
1913
1914 return 0;
1915}
1916
1917static int rbd_object_map_open(struct rbd_device *rbd_dev)
1918{
1919 int ret;
1920
1921 ret = rbd_object_map_lock(rbd_dev);
1922 if (ret)
1923 return ret;
1924
1925 ret = rbd_object_map_load(rbd_dev);
1926 if (ret) {
1927 rbd_object_map_unlock(rbd_dev);
1928 return ret;
1929 }
1930
1931 return 0;
1932}
1933
1934static void rbd_object_map_close(struct rbd_device *rbd_dev)
1935{
1936 rbd_object_map_free(rbd_dev);
1937 rbd_object_map_unlock(rbd_dev);
1938}
1939
1940/*
1941 * This function needs snap_id (or more precisely just something to
1942 * distinguish between HEAD and snapshot object maps), new_state and
1943 * current_state that were passed to rbd_object_map_update().
1944 *
1945 * To avoid allocating and stashing a context we piggyback on the OSD
1946 * request. A HEAD update has two ops (assert_locked). For new_state
1947 * and current_state we decode our own object_map_update op, encoded in
1948 * rbd_cls_object_map_update().
1949 */
1950static int rbd_object_map_update_finish(struct rbd_obj_request *obj_req,
1951 struct ceph_osd_request *osd_req)
1952{
1953 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
1954 struct ceph_osd_data *osd_data;
1955 u64 objno;
1956 u8 state, new_state, current_state;
1957 bool has_current_state;
1958 void *p;
1959
1960 if (osd_req->r_result)
1961 return osd_req->r_result;
1962
1963 /*
1964 * Nothing to do for a snapshot object map.
1965 */
1966 if (osd_req->r_num_ops == 1)
1967 return 0;
1968
1969 /*
1970 * Update in-memory HEAD object map.
1971 */
1972 rbd_assert(osd_req->r_num_ops == 2);
1973 osd_data = osd_req_op_data(osd_req, 1, cls, request_data);
1974 rbd_assert(osd_data->type == CEPH_OSD_DATA_TYPE_PAGES);
1975
1976 p = page_address(osd_data->pages[0]);
1977 objno = ceph_decode_64(&p);
1978 rbd_assert(objno == obj_req->ex.oe_objno);
1979 rbd_assert(ceph_decode_64(&p) == objno + 1);
1980 new_state = ceph_decode_8(&p);
1981 has_current_state = ceph_decode_8(&p);
1982 if (has_current_state)
1983 current_state = ceph_decode_8(&p);
1984
1985 spin_lock(&rbd_dev->object_map_lock);
1986 state = __rbd_object_map_get(rbd_dev, objno);
1987 if (!has_current_state || current_state == state ||
1988 (current_state == OBJECT_EXISTS && state == OBJECT_EXISTS_CLEAN))
1989 __rbd_object_map_set(rbd_dev, objno, new_state);
1990 spin_unlock(&rbd_dev->object_map_lock);
1991
1992 return 0;
1993}
1994
1995static void rbd_object_map_callback(struct ceph_osd_request *osd_req)
1996{
1997 struct rbd_obj_request *obj_req = osd_req->r_priv;
1998 int result;
1999
2000 dout("%s osd_req %p result %d for obj_req %p\n", __func__, osd_req,
2001 osd_req->r_result, obj_req);
2002
2003 result = rbd_object_map_update_finish(obj_req, osd_req);
2004 rbd_obj_handle_request(obj_req, result);
2005}
2006
2007static bool update_needed(struct rbd_device *rbd_dev, u64 objno, u8 new_state)
2008{
2009 u8 state = rbd_object_map_get(rbd_dev, objno);
2010
2011 if (state == new_state ||
2012 (new_state == OBJECT_PENDING && state == OBJECT_NONEXISTENT) ||
2013 (new_state == OBJECT_NONEXISTENT && state != OBJECT_PENDING))
2014 return false;
2015
2016 return true;
2017}
2018
2019static int rbd_cls_object_map_update(struct ceph_osd_request *req,
2020 int which, u64 objno, u8 new_state,
2021 const u8 *current_state)
2022{
2023 struct page **pages;
2024 void *p, *start;
2025 int ret;
2026
2027 ret = osd_req_op_cls_init(req, which, "rbd", "object_map_update");
2028 if (ret)
2029 return ret;
2030
2031 pages = ceph_alloc_page_vector(1, GFP_NOIO);
2032 if (IS_ERR(pages))
2033 return PTR_ERR(pages);
2034
2035 p = start = page_address(pages[0]);
2036 ceph_encode_64(&p, objno);
2037 ceph_encode_64(&p, objno + 1);
2038 ceph_encode_8(&p, new_state);
2039 if (current_state) {
2040 ceph_encode_8(&p, 1);
2041 ceph_encode_8(&p, *current_state);
2042 } else {
2043 ceph_encode_8(&p, 0);
2044 }
2045
2046 osd_req_op_cls_request_data_pages(req, which, pages, p - start, 0,
2047 false, true);
2048 return 0;
2049}
2050
2051/*
2052 * Return:
2053 * 0 - object map update sent
2054 * 1 - object map update isn't needed
2055 * <0 - error
2056 */
2057static int rbd_object_map_update(struct rbd_obj_request *obj_req, u64 snap_id,
2058 u8 new_state, const u8 *current_state)
2059{
2060 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2061 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2062 struct ceph_osd_request *req;
2063 int num_ops = 1;
2064 int which = 0;
2065 int ret;
2066
2067 if (snap_id == CEPH_NOSNAP) {
2068 if (!update_needed(rbd_dev, obj_req->ex.oe_objno, new_state))
2069 return 1;
2070
2071 num_ops++; /* assert_locked */
2072 }
2073
2074 req = ceph_osdc_alloc_request(osdc, NULL, num_ops, false, GFP_NOIO);
2075 if (!req)
2076 return -ENOMEM;
2077
2078 list_add_tail(&req->r_private_item, &obj_req->osd_reqs);
2079 req->r_callback = rbd_object_map_callback;
2080 req->r_priv = obj_req;
2081
2082 rbd_object_map_name(rbd_dev, snap_id, &req->r_base_oid);
2083 ceph_oloc_copy(&req->r_base_oloc, &rbd_dev->header_oloc);
2084 req->r_flags = CEPH_OSD_FLAG_WRITE;
2085 ktime_get_real_ts64(&req->r_mtime);
2086
2087 if (snap_id == CEPH_NOSNAP) {
2088 /*
2089 * Protect against possible race conditions during lock
2090 * ownership transitions.
2091 */
2092 ret = ceph_cls_assert_locked(req, which++, RBD_LOCK_NAME,
2093 CEPH_CLS_LOCK_EXCLUSIVE, "", "");
2094 if (ret)
2095 return ret;
2096 }
2097
2098 ret = rbd_cls_object_map_update(req, which, obj_req->ex.oe_objno,
2099 new_state, current_state);
2100 if (ret)
2101 return ret;
2102
2103 ret = ceph_osdc_alloc_messages(req, GFP_NOIO);
2104 if (ret)
2105 return ret;
2106
2107 ceph_osdc_start_request(osdc, req);
2108 return 0;
2109}
2110
2111static void prune_extents(struct ceph_file_extent *img_extents,
2112 u32 *num_img_extents, u64 overlap)
2113{
2114 u32 cnt = *num_img_extents;
2115
2116 /* drop extents completely beyond the overlap */
2117 while (cnt && img_extents[cnt - 1].fe_off >= overlap)
2118 cnt--;
2119
2120 if (cnt) {
2121 struct ceph_file_extent *ex = &img_extents[cnt - 1];
2122
2123 /* trim final overlapping extent */
2124 if (ex->fe_off + ex->fe_len > overlap)
2125 ex->fe_len = overlap - ex->fe_off;
2126 }
2127
2128 *num_img_extents = cnt;
2129}
2130
2131/*
2132 * Determine the byte range(s) covered by either just the object extent
2133 * or the entire object in the parent image.
2134 */
2135static int rbd_obj_calc_img_extents(struct rbd_obj_request *obj_req,
2136 bool entire)
2137{
2138 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2139 int ret;
2140
2141 if (!rbd_dev->parent_overlap)
2142 return 0;
2143
2144 ret = ceph_extent_to_file(&rbd_dev->layout, obj_req->ex.oe_objno,
2145 entire ? 0 : obj_req->ex.oe_off,
2146 entire ? rbd_dev->layout.object_size :
2147 obj_req->ex.oe_len,
2148 &obj_req->img_extents,
2149 &obj_req->num_img_extents);
2150 if (ret)
2151 return ret;
2152
2153 prune_extents(obj_req->img_extents, &obj_req->num_img_extents,
2154 rbd_dev->parent_overlap);
2155 return 0;
2156}
2157
2158static void rbd_osd_setup_data(struct ceph_osd_request *osd_req, int which)
2159{
2160 struct rbd_obj_request *obj_req = osd_req->r_priv;
2161
2162 switch (obj_req->img_request->data_type) {
2163 case OBJ_REQUEST_BIO:
2164 osd_req_op_extent_osd_data_bio(osd_req, which,
2165 &obj_req->bio_pos,
2166 obj_req->ex.oe_len);
2167 break;
2168 case OBJ_REQUEST_BVECS:
2169 case OBJ_REQUEST_OWN_BVECS:
2170 rbd_assert(obj_req->bvec_pos.iter.bi_size ==
2171 obj_req->ex.oe_len);
2172 rbd_assert(obj_req->bvec_idx == obj_req->bvec_count);
2173 osd_req_op_extent_osd_data_bvec_pos(osd_req, which,
2174 &obj_req->bvec_pos);
2175 break;
2176 default:
2177 BUG();
2178 }
2179}
2180
2181static int rbd_osd_setup_stat(struct ceph_osd_request *osd_req, int which)
2182{
2183 struct page **pages;
2184
2185 /*
2186 * The response data for a STAT call consists of:
2187 * le64 length;
2188 * struct {
2189 * le32 tv_sec;
2190 * le32 tv_nsec;
2191 * } mtime;
2192 */
2193 pages = ceph_alloc_page_vector(1, GFP_NOIO);
2194 if (IS_ERR(pages))
2195 return PTR_ERR(pages);
2196
2197 osd_req_op_init(osd_req, which, CEPH_OSD_OP_STAT, 0);
2198 osd_req_op_raw_data_in_pages(osd_req, which, pages,
2199 8 + sizeof(struct ceph_timespec),
2200 0, false, true);
2201 return 0;
2202}
2203
2204static int rbd_osd_setup_copyup(struct ceph_osd_request *osd_req, int which,
2205 u32 bytes)
2206{
2207 struct rbd_obj_request *obj_req = osd_req->r_priv;
2208 int ret;
2209
2210 ret = osd_req_op_cls_init(osd_req, which, "rbd", "copyup");
2211 if (ret)
2212 return ret;
2213
2214 osd_req_op_cls_request_data_bvecs(osd_req, which, obj_req->copyup_bvecs,
2215 obj_req->copyup_bvec_count, bytes);
2216 return 0;
2217}
2218
2219static int rbd_obj_init_read(struct rbd_obj_request *obj_req)
2220{
2221 obj_req->read_state = RBD_OBJ_READ_START;
2222 return 0;
2223}
2224
2225static void __rbd_osd_setup_write_ops(struct ceph_osd_request *osd_req,
2226 int which)
2227{
2228 struct rbd_obj_request *obj_req = osd_req->r_priv;
2229 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2230 u16 opcode;
2231
2232 if (!use_object_map(rbd_dev) ||
2233 !(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST)) {
2234 osd_req_op_alloc_hint_init(osd_req, which++,
2235 rbd_dev->layout.object_size,
2236 rbd_dev->layout.object_size,
2237 rbd_dev->opts->alloc_hint_flags);
2238 }
2239
2240 if (rbd_obj_is_entire(obj_req))
2241 opcode = CEPH_OSD_OP_WRITEFULL;
2242 else
2243 opcode = CEPH_OSD_OP_WRITE;
2244
2245 osd_req_op_extent_init(osd_req, which, opcode,
2246 obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0);
2247 rbd_osd_setup_data(osd_req, which);
2248}
2249
2250static int rbd_obj_init_write(struct rbd_obj_request *obj_req)
2251{
2252 int ret;
2253
2254 /* reverse map the entire object onto the parent */
2255 ret = rbd_obj_calc_img_extents(obj_req, true);
2256 if (ret)
2257 return ret;
2258
2259 obj_req->write_state = RBD_OBJ_WRITE_START;
2260 return 0;
2261}
2262
2263static u16 truncate_or_zero_opcode(struct rbd_obj_request *obj_req)
2264{
2265 return rbd_obj_is_tail(obj_req) ? CEPH_OSD_OP_TRUNCATE :
2266 CEPH_OSD_OP_ZERO;
2267}
2268
2269static void __rbd_osd_setup_discard_ops(struct ceph_osd_request *osd_req,
2270 int which)
2271{
2272 struct rbd_obj_request *obj_req = osd_req->r_priv;
2273
2274 if (rbd_obj_is_entire(obj_req) && !obj_req->num_img_extents) {
2275 rbd_assert(obj_req->flags & RBD_OBJ_FLAG_DELETION);
2276 osd_req_op_init(osd_req, which, CEPH_OSD_OP_DELETE, 0);
2277 } else {
2278 osd_req_op_extent_init(osd_req, which,
2279 truncate_or_zero_opcode(obj_req),
2280 obj_req->ex.oe_off, obj_req->ex.oe_len,
2281 0, 0);
2282 }
2283}
2284
2285static int rbd_obj_init_discard(struct rbd_obj_request *obj_req)
2286{
2287 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2288 u64 off, next_off;
2289 int ret;
2290
2291 /*
2292 * Align the range to alloc_size boundary and punt on discards
2293 * that are too small to free up any space.
2294 *
2295 * alloc_size == object_size && is_tail() is a special case for
2296 * filestore with filestore_punch_hole = false, needed to allow
2297 * truncate (in addition to delete).
2298 */
2299 if (rbd_dev->opts->alloc_size != rbd_dev->layout.object_size ||
2300 !rbd_obj_is_tail(obj_req)) {
2301 off = round_up(obj_req->ex.oe_off, rbd_dev->opts->alloc_size);
2302 next_off = round_down(obj_req->ex.oe_off + obj_req->ex.oe_len,
2303 rbd_dev->opts->alloc_size);
2304 if (off >= next_off)
2305 return 1;
2306
2307 dout("%s %p %llu~%llu -> %llu~%llu\n", __func__,
2308 obj_req, obj_req->ex.oe_off, obj_req->ex.oe_len,
2309 off, next_off - off);
2310 obj_req->ex.oe_off = off;
2311 obj_req->ex.oe_len = next_off - off;
2312 }
2313
2314 /* reverse map the entire object onto the parent */
2315 ret = rbd_obj_calc_img_extents(obj_req, true);
2316 if (ret)
2317 return ret;
2318
2319 obj_req->flags |= RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT;
2320 if (rbd_obj_is_entire(obj_req) && !obj_req->num_img_extents)
2321 obj_req->flags |= RBD_OBJ_FLAG_DELETION;
2322
2323 obj_req->write_state = RBD_OBJ_WRITE_START;
2324 return 0;
2325}
2326
2327static void __rbd_osd_setup_zeroout_ops(struct ceph_osd_request *osd_req,
2328 int which)
2329{
2330 struct rbd_obj_request *obj_req = osd_req->r_priv;
2331 u16 opcode;
2332
2333 if (rbd_obj_is_entire(obj_req)) {
2334 if (obj_req->num_img_extents) {
2335 if (!(obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED))
2336 osd_req_op_init(osd_req, which++,
2337 CEPH_OSD_OP_CREATE, 0);
2338 opcode = CEPH_OSD_OP_TRUNCATE;
2339 } else {
2340 rbd_assert(obj_req->flags & RBD_OBJ_FLAG_DELETION);
2341 osd_req_op_init(osd_req, which++,
2342 CEPH_OSD_OP_DELETE, 0);
2343 opcode = 0;
2344 }
2345 } else {
2346 opcode = truncate_or_zero_opcode(obj_req);
2347 }
2348
2349 if (opcode)
2350 osd_req_op_extent_init(osd_req, which, opcode,
2351 obj_req->ex.oe_off, obj_req->ex.oe_len,
2352 0, 0);
2353}
2354
2355static int rbd_obj_init_zeroout(struct rbd_obj_request *obj_req)
2356{
2357 int ret;
2358
2359 /* reverse map the entire object onto the parent */
2360 ret = rbd_obj_calc_img_extents(obj_req, true);
2361 if (ret)
2362 return ret;
2363
2364 if (!obj_req->num_img_extents) {
2365 obj_req->flags |= RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT;
2366 if (rbd_obj_is_entire(obj_req))
2367 obj_req->flags |= RBD_OBJ_FLAG_DELETION;
2368 }
2369
2370 obj_req->write_state = RBD_OBJ_WRITE_START;
2371 return 0;
2372}
2373
2374static int count_write_ops(struct rbd_obj_request *obj_req)
2375{
2376 struct rbd_img_request *img_req = obj_req->img_request;
2377
2378 switch (img_req->op_type) {
2379 case OBJ_OP_WRITE:
2380 if (!use_object_map(img_req->rbd_dev) ||
2381 !(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST))
2382 return 2; /* setallochint + write/writefull */
2383
2384 return 1; /* write/writefull */
2385 case OBJ_OP_DISCARD:
2386 return 1; /* delete/truncate/zero */
2387 case OBJ_OP_ZEROOUT:
2388 if (rbd_obj_is_entire(obj_req) && obj_req->num_img_extents &&
2389 !(obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED))
2390 return 2; /* create + truncate */
2391
2392 return 1; /* delete/truncate/zero */
2393 default:
2394 BUG();
2395 }
2396}
2397
2398static void rbd_osd_setup_write_ops(struct ceph_osd_request *osd_req,
2399 int which)
2400{
2401 struct rbd_obj_request *obj_req = osd_req->r_priv;
2402
2403 switch (obj_req->img_request->op_type) {
2404 case OBJ_OP_WRITE:
2405 __rbd_osd_setup_write_ops(osd_req, which);
2406 break;
2407 case OBJ_OP_DISCARD:
2408 __rbd_osd_setup_discard_ops(osd_req, which);
2409 break;
2410 case OBJ_OP_ZEROOUT:
2411 __rbd_osd_setup_zeroout_ops(osd_req, which);
2412 break;
2413 default:
2414 BUG();
2415 }
2416}
2417
2418/*
2419 * Prune the list of object requests (adjust offset and/or length, drop
2420 * redundant requests). Prepare object request state machines and image
2421 * request state machine for execution.
2422 */
2423static int __rbd_img_fill_request(struct rbd_img_request *img_req)
2424{
2425 struct rbd_obj_request *obj_req, *next_obj_req;
2426 int ret;
2427
2428 for_each_obj_request_safe(img_req, obj_req, next_obj_req) {
2429 switch (img_req->op_type) {
2430 case OBJ_OP_READ:
2431 ret = rbd_obj_init_read(obj_req);
2432 break;
2433 case OBJ_OP_WRITE:
2434 ret = rbd_obj_init_write(obj_req);
2435 break;
2436 case OBJ_OP_DISCARD:
2437 ret = rbd_obj_init_discard(obj_req);
2438 break;
2439 case OBJ_OP_ZEROOUT:
2440 ret = rbd_obj_init_zeroout(obj_req);
2441 break;
2442 default:
2443 BUG();
2444 }
2445 if (ret < 0)
2446 return ret;
2447 if (ret > 0) {
2448 rbd_img_obj_request_del(img_req, obj_req);
2449 continue;
2450 }
2451 }
2452
2453 img_req->state = RBD_IMG_START;
2454 return 0;
2455}
2456
2457union rbd_img_fill_iter {
2458 struct ceph_bio_iter bio_iter;
2459 struct ceph_bvec_iter bvec_iter;
2460};
2461
2462struct rbd_img_fill_ctx {
2463 enum obj_request_type pos_type;
2464 union rbd_img_fill_iter *pos;
2465 union rbd_img_fill_iter iter;
2466 ceph_object_extent_fn_t set_pos_fn;
2467 ceph_object_extent_fn_t count_fn;
2468 ceph_object_extent_fn_t copy_fn;
2469};
2470
2471static struct ceph_object_extent *alloc_object_extent(void *arg)
2472{
2473 struct rbd_img_request *img_req = arg;
2474 struct rbd_obj_request *obj_req;
2475
2476 obj_req = rbd_obj_request_create();
2477 if (!obj_req)
2478 return NULL;
2479
2480 rbd_img_obj_request_add(img_req, obj_req);
2481 return &obj_req->ex;
2482}
2483
2484/*
2485 * While su != os && sc == 1 is technically not fancy (it's the same
2486 * layout as su == os && sc == 1), we can't use the nocopy path for it
2487 * because ->set_pos_fn() should be called only once per object.
2488 * ceph_file_to_extents() invokes action_fn once per stripe unit, so
2489 * treat su != os && sc == 1 as fancy.
2490 */
2491static bool rbd_layout_is_fancy(struct ceph_file_layout *l)
2492{
2493 return l->stripe_unit != l->object_size;
2494}
2495
2496static int rbd_img_fill_request_nocopy(struct rbd_img_request *img_req,
2497 struct ceph_file_extent *img_extents,
2498 u32 num_img_extents,
2499 struct rbd_img_fill_ctx *fctx)
2500{
2501 u32 i;
2502 int ret;
2503
2504 img_req->data_type = fctx->pos_type;
2505
2506 /*
2507 * Create object requests and set each object request's starting
2508 * position in the provided bio (list) or bio_vec array.
2509 */
2510 fctx->iter = *fctx->pos;
2511 for (i = 0; i < num_img_extents; i++) {
2512 ret = ceph_file_to_extents(&img_req->rbd_dev->layout,
2513 img_extents[i].fe_off,
2514 img_extents[i].fe_len,
2515 &img_req->object_extents,
2516 alloc_object_extent, img_req,
2517 fctx->set_pos_fn, &fctx->iter);
2518 if (ret)
2519 return ret;
2520 }
2521
2522 return __rbd_img_fill_request(img_req);
2523}
2524
2525/*
2526 * Map a list of image extents to a list of object extents, create the
2527 * corresponding object requests (normally each to a different object,
2528 * but not always) and add them to @img_req. For each object request,
2529 * set up its data descriptor to point to the corresponding chunk(s) of
2530 * @fctx->pos data buffer.
2531 *
2532 * Because ceph_file_to_extents() will merge adjacent object extents
2533 * together, each object request's data descriptor may point to multiple
2534 * different chunks of @fctx->pos data buffer.
2535 *
2536 * @fctx->pos data buffer is assumed to be large enough.
2537 */
2538static int rbd_img_fill_request(struct rbd_img_request *img_req,
2539 struct ceph_file_extent *img_extents,
2540 u32 num_img_extents,
2541 struct rbd_img_fill_ctx *fctx)
2542{
2543 struct rbd_device *rbd_dev = img_req->rbd_dev;
2544 struct rbd_obj_request *obj_req;
2545 u32 i;
2546 int ret;
2547
2548 if (fctx->pos_type == OBJ_REQUEST_NODATA ||
2549 !rbd_layout_is_fancy(&rbd_dev->layout))
2550 return rbd_img_fill_request_nocopy(img_req, img_extents,
2551 num_img_extents, fctx);
2552
2553 img_req->data_type = OBJ_REQUEST_OWN_BVECS;
2554
2555 /*
2556 * Create object requests and determine ->bvec_count for each object
2557 * request. Note that ->bvec_count sum over all object requests may
2558 * be greater than the number of bio_vecs in the provided bio (list)
2559 * or bio_vec array because when mapped, those bio_vecs can straddle
2560 * stripe unit boundaries.
2561 */
2562 fctx->iter = *fctx->pos;
2563 for (i = 0; i < num_img_extents; i++) {
2564 ret = ceph_file_to_extents(&rbd_dev->layout,
2565 img_extents[i].fe_off,
2566 img_extents[i].fe_len,
2567 &img_req->object_extents,
2568 alloc_object_extent, img_req,
2569 fctx->count_fn, &fctx->iter);
2570 if (ret)
2571 return ret;
2572 }
2573
2574 for_each_obj_request(img_req, obj_req) {
2575 obj_req->bvec_pos.bvecs = kmalloc_array(obj_req->bvec_count,
2576 sizeof(*obj_req->bvec_pos.bvecs),
2577 GFP_NOIO);
2578 if (!obj_req->bvec_pos.bvecs)
2579 return -ENOMEM;
2580 }
2581
2582 /*
2583 * Fill in each object request's private bio_vec array, splitting and
2584 * rearranging the provided bio_vecs in stripe unit chunks as needed.
2585 */
2586 fctx->iter = *fctx->pos;
2587 for (i = 0; i < num_img_extents; i++) {
2588 ret = ceph_iterate_extents(&rbd_dev->layout,
2589 img_extents[i].fe_off,
2590 img_extents[i].fe_len,
2591 &img_req->object_extents,
2592 fctx->copy_fn, &fctx->iter);
2593 if (ret)
2594 return ret;
2595 }
2596
2597 return __rbd_img_fill_request(img_req);
2598}
2599
2600static int rbd_img_fill_nodata(struct rbd_img_request *img_req,
2601 u64 off, u64 len)
2602{
2603 struct ceph_file_extent ex = { off, len };
2604 union rbd_img_fill_iter dummy = {};
2605 struct rbd_img_fill_ctx fctx = {
2606 .pos_type = OBJ_REQUEST_NODATA,
2607 .pos = &dummy,
2608 };
2609
2610 return rbd_img_fill_request(img_req, &ex, 1, &fctx);
2611}
2612
2613static void set_bio_pos(struct ceph_object_extent *ex, u32 bytes, void *arg)
2614{
2615 struct rbd_obj_request *obj_req =
2616 container_of(ex, struct rbd_obj_request, ex);
2617 struct ceph_bio_iter *it = arg;
2618
2619 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
2620 obj_req->bio_pos = *it;
2621 ceph_bio_iter_advance(it, bytes);
2622}
2623
2624static void count_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2625{
2626 struct rbd_obj_request *obj_req =
2627 container_of(ex, struct rbd_obj_request, ex);
2628 struct ceph_bio_iter *it = arg;
2629
2630 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
2631 ceph_bio_iter_advance_step(it, bytes, ({
2632 obj_req->bvec_count++;
2633 }));
2634
2635}
2636
2637static void copy_bio_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2638{
2639 struct rbd_obj_request *obj_req =
2640 container_of(ex, struct rbd_obj_request, ex);
2641 struct ceph_bio_iter *it = arg;
2642
2643 dout("%s objno %llu bytes %u\n", __func__, ex->oe_objno, bytes);
2644 ceph_bio_iter_advance_step(it, bytes, ({
2645 obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv;
2646 obj_req->bvec_pos.iter.bi_size += bv.bv_len;
2647 }));
2648}
2649
2650static int __rbd_img_fill_from_bio(struct rbd_img_request *img_req,
2651 struct ceph_file_extent *img_extents,
2652 u32 num_img_extents,
2653 struct ceph_bio_iter *bio_pos)
2654{
2655 struct rbd_img_fill_ctx fctx = {
2656 .pos_type = OBJ_REQUEST_BIO,
2657 .pos = (union rbd_img_fill_iter *)bio_pos,
2658 .set_pos_fn = set_bio_pos,
2659 .count_fn = count_bio_bvecs,
2660 .copy_fn = copy_bio_bvecs,
2661 };
2662
2663 return rbd_img_fill_request(img_req, img_extents, num_img_extents,
2664 &fctx);
2665}
2666
2667static int rbd_img_fill_from_bio(struct rbd_img_request *img_req,
2668 u64 off, u64 len, struct bio *bio)
2669{
2670 struct ceph_file_extent ex = { off, len };
2671 struct ceph_bio_iter it = { .bio = bio, .iter = bio->bi_iter };
2672
2673 return __rbd_img_fill_from_bio(img_req, &ex, 1, &it);
2674}
2675
2676static void set_bvec_pos(struct ceph_object_extent *ex, u32 bytes, void *arg)
2677{
2678 struct rbd_obj_request *obj_req =
2679 container_of(ex, struct rbd_obj_request, ex);
2680 struct ceph_bvec_iter *it = arg;
2681
2682 obj_req->bvec_pos = *it;
2683 ceph_bvec_iter_shorten(&obj_req->bvec_pos, bytes);
2684 ceph_bvec_iter_advance(it, bytes);
2685}
2686
2687static void count_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2688{
2689 struct rbd_obj_request *obj_req =
2690 container_of(ex, struct rbd_obj_request, ex);
2691 struct ceph_bvec_iter *it = arg;
2692
2693 ceph_bvec_iter_advance_step(it, bytes, ({
2694 obj_req->bvec_count++;
2695 }));
2696}
2697
2698static void copy_bvecs(struct ceph_object_extent *ex, u32 bytes, void *arg)
2699{
2700 struct rbd_obj_request *obj_req =
2701 container_of(ex, struct rbd_obj_request, ex);
2702 struct ceph_bvec_iter *it = arg;
2703
2704 ceph_bvec_iter_advance_step(it, bytes, ({
2705 obj_req->bvec_pos.bvecs[obj_req->bvec_idx++] = bv;
2706 obj_req->bvec_pos.iter.bi_size += bv.bv_len;
2707 }));
2708}
2709
2710static int __rbd_img_fill_from_bvecs(struct rbd_img_request *img_req,
2711 struct ceph_file_extent *img_extents,
2712 u32 num_img_extents,
2713 struct ceph_bvec_iter *bvec_pos)
2714{
2715 struct rbd_img_fill_ctx fctx = {
2716 .pos_type = OBJ_REQUEST_BVECS,
2717 .pos = (union rbd_img_fill_iter *)bvec_pos,
2718 .set_pos_fn = set_bvec_pos,
2719 .count_fn = count_bvecs,
2720 .copy_fn = copy_bvecs,
2721 };
2722
2723 return rbd_img_fill_request(img_req, img_extents, num_img_extents,
2724 &fctx);
2725}
2726
2727static int rbd_img_fill_from_bvecs(struct rbd_img_request *img_req,
2728 struct ceph_file_extent *img_extents,
2729 u32 num_img_extents,
2730 struct bio_vec *bvecs)
2731{
2732 struct ceph_bvec_iter it = {
2733 .bvecs = bvecs,
2734 .iter = { .bi_size = ceph_file_extents_bytes(img_extents,
2735 num_img_extents) },
2736 };
2737
2738 return __rbd_img_fill_from_bvecs(img_req, img_extents, num_img_extents,
2739 &it);
2740}
2741
2742static void rbd_img_handle_request_work(struct work_struct *work)
2743{
2744 struct rbd_img_request *img_req =
2745 container_of(work, struct rbd_img_request, work);
2746
2747 rbd_img_handle_request(img_req, img_req->work_result);
2748}
2749
2750static void rbd_img_schedule(struct rbd_img_request *img_req, int result)
2751{
2752 INIT_WORK(&img_req->work, rbd_img_handle_request_work);
2753 img_req->work_result = result;
2754 queue_work(rbd_wq, &img_req->work);
2755}
2756
2757static bool rbd_obj_may_exist(struct rbd_obj_request *obj_req)
2758{
2759 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2760
2761 if (rbd_object_map_may_exist(rbd_dev, obj_req->ex.oe_objno)) {
2762 obj_req->flags |= RBD_OBJ_FLAG_MAY_EXIST;
2763 return true;
2764 }
2765
2766 dout("%s %p objno %llu assuming dne\n", __func__, obj_req,
2767 obj_req->ex.oe_objno);
2768 return false;
2769}
2770
2771static int rbd_obj_read_object(struct rbd_obj_request *obj_req)
2772{
2773 struct ceph_osd_request *osd_req;
2774 int ret;
2775
2776 osd_req = __rbd_obj_add_osd_request(obj_req, NULL, 1);
2777 if (IS_ERR(osd_req))
2778 return PTR_ERR(osd_req);
2779
2780 osd_req_op_extent_init(osd_req, 0, CEPH_OSD_OP_READ,
2781 obj_req->ex.oe_off, obj_req->ex.oe_len, 0, 0);
2782 rbd_osd_setup_data(osd_req, 0);
2783 rbd_osd_format_read(osd_req);
2784
2785 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
2786 if (ret)
2787 return ret;
2788
2789 rbd_osd_submit(osd_req);
2790 return 0;
2791}
2792
2793static int rbd_obj_read_from_parent(struct rbd_obj_request *obj_req)
2794{
2795 struct rbd_img_request *img_req = obj_req->img_request;
2796 struct rbd_device *parent = img_req->rbd_dev->parent;
2797 struct rbd_img_request *child_img_req;
2798 int ret;
2799
2800 child_img_req = kmem_cache_alloc(rbd_img_request_cache, GFP_NOIO);
2801 if (!child_img_req)
2802 return -ENOMEM;
2803
2804 rbd_img_request_init(child_img_req, parent, OBJ_OP_READ);
2805 __set_bit(IMG_REQ_CHILD, &child_img_req->flags);
2806 child_img_req->obj_request = obj_req;
2807
2808 down_read(&parent->header_rwsem);
2809 rbd_img_capture_header(child_img_req);
2810 up_read(&parent->header_rwsem);
2811
2812 dout("%s child_img_req %p for obj_req %p\n", __func__, child_img_req,
2813 obj_req);
2814
2815 if (!rbd_img_is_write(img_req)) {
2816 switch (img_req->data_type) {
2817 case OBJ_REQUEST_BIO:
2818 ret = __rbd_img_fill_from_bio(child_img_req,
2819 obj_req->img_extents,
2820 obj_req->num_img_extents,
2821 &obj_req->bio_pos);
2822 break;
2823 case OBJ_REQUEST_BVECS:
2824 case OBJ_REQUEST_OWN_BVECS:
2825 ret = __rbd_img_fill_from_bvecs(child_img_req,
2826 obj_req->img_extents,
2827 obj_req->num_img_extents,
2828 &obj_req->bvec_pos);
2829 break;
2830 default:
2831 BUG();
2832 }
2833 } else {
2834 ret = rbd_img_fill_from_bvecs(child_img_req,
2835 obj_req->img_extents,
2836 obj_req->num_img_extents,
2837 obj_req->copyup_bvecs);
2838 }
2839 if (ret) {
2840 rbd_img_request_destroy(child_img_req);
2841 return ret;
2842 }
2843
2844 /* avoid parent chain recursion */
2845 rbd_img_schedule(child_img_req, 0);
2846 return 0;
2847}
2848
2849static bool rbd_obj_advance_read(struct rbd_obj_request *obj_req, int *result)
2850{
2851 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2852 int ret;
2853
2854again:
2855 switch (obj_req->read_state) {
2856 case RBD_OBJ_READ_START:
2857 rbd_assert(!*result);
2858
2859 if (!rbd_obj_may_exist(obj_req)) {
2860 *result = -ENOENT;
2861 obj_req->read_state = RBD_OBJ_READ_OBJECT;
2862 goto again;
2863 }
2864
2865 ret = rbd_obj_read_object(obj_req);
2866 if (ret) {
2867 *result = ret;
2868 return true;
2869 }
2870 obj_req->read_state = RBD_OBJ_READ_OBJECT;
2871 return false;
2872 case RBD_OBJ_READ_OBJECT:
2873 if (*result == -ENOENT && rbd_dev->parent_overlap) {
2874 /* reverse map this object extent onto the parent */
2875 ret = rbd_obj_calc_img_extents(obj_req, false);
2876 if (ret) {
2877 *result = ret;
2878 return true;
2879 }
2880 if (obj_req->num_img_extents) {
2881 ret = rbd_obj_read_from_parent(obj_req);
2882 if (ret) {
2883 *result = ret;
2884 return true;
2885 }
2886 obj_req->read_state = RBD_OBJ_READ_PARENT;
2887 return false;
2888 }
2889 }
2890
2891 /*
2892 * -ENOENT means a hole in the image -- zero-fill the entire
2893 * length of the request. A short read also implies zero-fill
2894 * to the end of the request.
2895 */
2896 if (*result == -ENOENT) {
2897 rbd_obj_zero_range(obj_req, 0, obj_req->ex.oe_len);
2898 *result = 0;
2899 } else if (*result >= 0) {
2900 if (*result < obj_req->ex.oe_len)
2901 rbd_obj_zero_range(obj_req, *result,
2902 obj_req->ex.oe_len - *result);
2903 else
2904 rbd_assert(*result == obj_req->ex.oe_len);
2905 *result = 0;
2906 }
2907 return true;
2908 case RBD_OBJ_READ_PARENT:
2909 /*
2910 * The parent image is read only up to the overlap -- zero-fill
2911 * from the overlap to the end of the request.
2912 */
2913 if (!*result) {
2914 u32 obj_overlap = rbd_obj_img_extents_bytes(obj_req);
2915
2916 if (obj_overlap < obj_req->ex.oe_len)
2917 rbd_obj_zero_range(obj_req, obj_overlap,
2918 obj_req->ex.oe_len - obj_overlap);
2919 }
2920 return true;
2921 default:
2922 BUG();
2923 }
2924}
2925
2926static bool rbd_obj_write_is_noop(struct rbd_obj_request *obj_req)
2927{
2928 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2929
2930 if (rbd_object_map_may_exist(rbd_dev, obj_req->ex.oe_objno))
2931 obj_req->flags |= RBD_OBJ_FLAG_MAY_EXIST;
2932
2933 if (!(obj_req->flags & RBD_OBJ_FLAG_MAY_EXIST) &&
2934 (obj_req->flags & RBD_OBJ_FLAG_NOOP_FOR_NONEXISTENT)) {
2935 dout("%s %p noop for nonexistent\n", __func__, obj_req);
2936 return true;
2937 }
2938
2939 return false;
2940}
2941
2942/*
2943 * Return:
2944 * 0 - object map update sent
2945 * 1 - object map update isn't needed
2946 * <0 - error
2947 */
2948static int rbd_obj_write_pre_object_map(struct rbd_obj_request *obj_req)
2949{
2950 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
2951 u8 new_state;
2952
2953 if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
2954 return 1;
2955
2956 if (obj_req->flags & RBD_OBJ_FLAG_DELETION)
2957 new_state = OBJECT_PENDING;
2958 else
2959 new_state = OBJECT_EXISTS;
2960
2961 return rbd_object_map_update(obj_req, CEPH_NOSNAP, new_state, NULL);
2962}
2963
2964static int rbd_obj_write_object(struct rbd_obj_request *obj_req)
2965{
2966 struct ceph_osd_request *osd_req;
2967 int num_ops = count_write_ops(obj_req);
2968 int which = 0;
2969 int ret;
2970
2971 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED)
2972 num_ops++; /* stat */
2973
2974 osd_req = rbd_obj_add_osd_request(obj_req, num_ops);
2975 if (IS_ERR(osd_req))
2976 return PTR_ERR(osd_req);
2977
2978 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) {
2979 ret = rbd_osd_setup_stat(osd_req, which++);
2980 if (ret)
2981 return ret;
2982 }
2983
2984 rbd_osd_setup_write_ops(osd_req, which);
2985 rbd_osd_format_write(osd_req);
2986
2987 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
2988 if (ret)
2989 return ret;
2990
2991 rbd_osd_submit(osd_req);
2992 return 0;
2993}
2994
2995/*
2996 * copyup_bvecs pages are never highmem pages
2997 */
2998static bool is_zero_bvecs(struct bio_vec *bvecs, u32 bytes)
2999{
3000 struct ceph_bvec_iter it = {
3001 .bvecs = bvecs,
3002 .iter = { .bi_size = bytes },
3003 };
3004
3005 ceph_bvec_iter_advance_step(&it, bytes, ({
3006 if (memchr_inv(bvec_virt(&bv), 0, bv.bv_len))
3007 return false;
3008 }));
3009 return true;
3010}
3011
3012#define MODS_ONLY U32_MAX
3013
3014static int rbd_obj_copyup_empty_snapc(struct rbd_obj_request *obj_req,
3015 u32 bytes)
3016{
3017 struct ceph_osd_request *osd_req;
3018 int ret;
3019
3020 dout("%s obj_req %p bytes %u\n", __func__, obj_req, bytes);
3021 rbd_assert(bytes > 0 && bytes != MODS_ONLY);
3022
3023 osd_req = __rbd_obj_add_osd_request(obj_req, &rbd_empty_snapc, 1);
3024 if (IS_ERR(osd_req))
3025 return PTR_ERR(osd_req);
3026
3027 ret = rbd_osd_setup_copyup(osd_req, 0, bytes);
3028 if (ret)
3029 return ret;
3030
3031 rbd_osd_format_write(osd_req);
3032
3033 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
3034 if (ret)
3035 return ret;
3036
3037 rbd_osd_submit(osd_req);
3038 return 0;
3039}
3040
3041static int rbd_obj_copyup_current_snapc(struct rbd_obj_request *obj_req,
3042 u32 bytes)
3043{
3044 struct ceph_osd_request *osd_req;
3045 int num_ops = count_write_ops(obj_req);
3046 int which = 0;
3047 int ret;
3048
3049 dout("%s obj_req %p bytes %u\n", __func__, obj_req, bytes);
3050
3051 if (bytes != MODS_ONLY)
3052 num_ops++; /* copyup */
3053
3054 osd_req = rbd_obj_add_osd_request(obj_req, num_ops);
3055 if (IS_ERR(osd_req))
3056 return PTR_ERR(osd_req);
3057
3058 if (bytes != MODS_ONLY) {
3059 ret = rbd_osd_setup_copyup(osd_req, which++, bytes);
3060 if (ret)
3061 return ret;
3062 }
3063
3064 rbd_osd_setup_write_ops(osd_req, which);
3065 rbd_osd_format_write(osd_req);
3066
3067 ret = ceph_osdc_alloc_messages(osd_req, GFP_NOIO);
3068 if (ret)
3069 return ret;
3070
3071 rbd_osd_submit(osd_req);
3072 return 0;
3073}
3074
3075static int setup_copyup_bvecs(struct rbd_obj_request *obj_req, u64 obj_overlap)
3076{
3077 u32 i;
3078
3079 rbd_assert(!obj_req->copyup_bvecs);
3080 obj_req->copyup_bvec_count = calc_pages_for(0, obj_overlap);
3081 obj_req->copyup_bvecs = kcalloc(obj_req->copyup_bvec_count,
3082 sizeof(*obj_req->copyup_bvecs),
3083 GFP_NOIO);
3084 if (!obj_req->copyup_bvecs)
3085 return -ENOMEM;
3086
3087 for (i = 0; i < obj_req->copyup_bvec_count; i++) {
3088 unsigned int len = min(obj_overlap, (u64)PAGE_SIZE);
3089 struct page *page = alloc_page(GFP_NOIO);
3090
3091 if (!page)
3092 return -ENOMEM;
3093
3094 bvec_set_page(&obj_req->copyup_bvecs[i], page, len, 0);
3095 obj_overlap -= len;
3096 }
3097
3098 rbd_assert(!obj_overlap);
3099 return 0;
3100}
3101
3102/*
3103 * The target object doesn't exist. Read the data for the entire
3104 * target object up to the overlap point (if any) from the parent,
3105 * so we can use it for a copyup.
3106 */
3107static int rbd_obj_copyup_read_parent(struct rbd_obj_request *obj_req)
3108{
3109 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3110 int ret;
3111
3112 rbd_assert(obj_req->num_img_extents);
3113 prune_extents(obj_req->img_extents, &obj_req->num_img_extents,
3114 rbd_dev->parent_overlap);
3115 if (!obj_req->num_img_extents) {
3116 /*
3117 * The overlap has become 0 (most likely because the
3118 * image has been flattened). Re-submit the original write
3119 * request -- pass MODS_ONLY since the copyup isn't needed
3120 * anymore.
3121 */
3122 return rbd_obj_copyup_current_snapc(obj_req, MODS_ONLY);
3123 }
3124
3125 ret = setup_copyup_bvecs(obj_req, rbd_obj_img_extents_bytes(obj_req));
3126 if (ret)
3127 return ret;
3128
3129 return rbd_obj_read_from_parent(obj_req);
3130}
3131
3132static void rbd_obj_copyup_object_maps(struct rbd_obj_request *obj_req)
3133{
3134 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3135 struct ceph_snap_context *snapc = obj_req->img_request->snapc;
3136 u8 new_state;
3137 u32 i;
3138 int ret;
3139
3140 rbd_assert(!obj_req->pending.result && !obj_req->pending.num_pending);
3141
3142 if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
3143 return;
3144
3145 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ZEROS)
3146 return;
3147
3148 for (i = 0; i < snapc->num_snaps; i++) {
3149 if ((rbd_dev->header.features & RBD_FEATURE_FAST_DIFF) &&
3150 i + 1 < snapc->num_snaps)
3151 new_state = OBJECT_EXISTS_CLEAN;
3152 else
3153 new_state = OBJECT_EXISTS;
3154
3155 ret = rbd_object_map_update(obj_req, snapc->snaps[i],
3156 new_state, NULL);
3157 if (ret < 0) {
3158 obj_req->pending.result = ret;
3159 return;
3160 }
3161
3162 rbd_assert(!ret);
3163 obj_req->pending.num_pending++;
3164 }
3165}
3166
3167static void rbd_obj_copyup_write_object(struct rbd_obj_request *obj_req)
3168{
3169 u32 bytes = rbd_obj_img_extents_bytes(obj_req);
3170 int ret;
3171
3172 rbd_assert(!obj_req->pending.result && !obj_req->pending.num_pending);
3173
3174 /*
3175 * Only send non-zero copyup data to save some I/O and network
3176 * bandwidth -- zero copyup data is equivalent to the object not
3177 * existing.
3178 */
3179 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ZEROS)
3180 bytes = 0;
3181
3182 if (obj_req->img_request->snapc->num_snaps && bytes > 0) {
3183 /*
3184 * Send a copyup request with an empty snapshot context to
3185 * deep-copyup the object through all existing snapshots.
3186 * A second request with the current snapshot context will be
3187 * sent for the actual modification.
3188 */
3189 ret = rbd_obj_copyup_empty_snapc(obj_req, bytes);
3190 if (ret) {
3191 obj_req->pending.result = ret;
3192 return;
3193 }
3194
3195 obj_req->pending.num_pending++;
3196 bytes = MODS_ONLY;
3197 }
3198
3199 ret = rbd_obj_copyup_current_snapc(obj_req, bytes);
3200 if (ret) {
3201 obj_req->pending.result = ret;
3202 return;
3203 }
3204
3205 obj_req->pending.num_pending++;
3206}
3207
3208static bool rbd_obj_advance_copyup(struct rbd_obj_request *obj_req, int *result)
3209{
3210 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3211 int ret;
3212
3213again:
3214 switch (obj_req->copyup_state) {
3215 case RBD_OBJ_COPYUP_START:
3216 rbd_assert(!*result);
3217
3218 ret = rbd_obj_copyup_read_parent(obj_req);
3219 if (ret) {
3220 *result = ret;
3221 return true;
3222 }
3223 if (obj_req->num_img_extents)
3224 obj_req->copyup_state = RBD_OBJ_COPYUP_READ_PARENT;
3225 else
3226 obj_req->copyup_state = RBD_OBJ_COPYUP_WRITE_OBJECT;
3227 return false;
3228 case RBD_OBJ_COPYUP_READ_PARENT:
3229 if (*result)
3230 return true;
3231
3232 if (is_zero_bvecs(obj_req->copyup_bvecs,
3233 rbd_obj_img_extents_bytes(obj_req))) {
3234 dout("%s %p detected zeros\n", __func__, obj_req);
3235 obj_req->flags |= RBD_OBJ_FLAG_COPYUP_ZEROS;
3236 }
3237
3238 rbd_obj_copyup_object_maps(obj_req);
3239 if (!obj_req->pending.num_pending) {
3240 *result = obj_req->pending.result;
3241 obj_req->copyup_state = RBD_OBJ_COPYUP_OBJECT_MAPS;
3242 goto again;
3243 }
3244 obj_req->copyup_state = __RBD_OBJ_COPYUP_OBJECT_MAPS;
3245 return false;
3246 case __RBD_OBJ_COPYUP_OBJECT_MAPS:
3247 if (!pending_result_dec(&obj_req->pending, result))
3248 return false;
3249 fallthrough;
3250 case RBD_OBJ_COPYUP_OBJECT_MAPS:
3251 if (*result) {
3252 rbd_warn(rbd_dev, "snap object map update failed: %d",
3253 *result);
3254 return true;
3255 }
3256
3257 rbd_obj_copyup_write_object(obj_req);
3258 if (!obj_req->pending.num_pending) {
3259 *result = obj_req->pending.result;
3260 obj_req->copyup_state = RBD_OBJ_COPYUP_WRITE_OBJECT;
3261 goto again;
3262 }
3263 obj_req->copyup_state = __RBD_OBJ_COPYUP_WRITE_OBJECT;
3264 return false;
3265 case __RBD_OBJ_COPYUP_WRITE_OBJECT:
3266 if (!pending_result_dec(&obj_req->pending, result))
3267 return false;
3268 fallthrough;
3269 case RBD_OBJ_COPYUP_WRITE_OBJECT:
3270 return true;
3271 default:
3272 BUG();
3273 }
3274}
3275
3276/*
3277 * Return:
3278 * 0 - object map update sent
3279 * 1 - object map update isn't needed
3280 * <0 - error
3281 */
3282static int rbd_obj_write_post_object_map(struct rbd_obj_request *obj_req)
3283{
3284 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3285 u8 current_state = OBJECT_PENDING;
3286
3287 if (!(rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
3288 return 1;
3289
3290 if (!(obj_req->flags & RBD_OBJ_FLAG_DELETION))
3291 return 1;
3292
3293 return rbd_object_map_update(obj_req, CEPH_NOSNAP, OBJECT_NONEXISTENT,
3294 &current_state);
3295}
3296
3297static bool rbd_obj_advance_write(struct rbd_obj_request *obj_req, int *result)
3298{
3299 struct rbd_device *rbd_dev = obj_req->img_request->rbd_dev;
3300 int ret;
3301
3302again:
3303 switch (obj_req->write_state) {
3304 case RBD_OBJ_WRITE_START:
3305 rbd_assert(!*result);
3306
3307 rbd_obj_set_copyup_enabled(obj_req);
3308 if (rbd_obj_write_is_noop(obj_req))
3309 return true;
3310
3311 ret = rbd_obj_write_pre_object_map(obj_req);
3312 if (ret < 0) {
3313 *result = ret;
3314 return true;
3315 }
3316 obj_req->write_state = RBD_OBJ_WRITE_PRE_OBJECT_MAP;
3317 if (ret > 0)
3318 goto again;
3319 return false;
3320 case RBD_OBJ_WRITE_PRE_OBJECT_MAP:
3321 if (*result) {
3322 rbd_warn(rbd_dev, "pre object map update failed: %d",
3323 *result);
3324 return true;
3325 }
3326 ret = rbd_obj_write_object(obj_req);
3327 if (ret) {
3328 *result = ret;
3329 return true;
3330 }
3331 obj_req->write_state = RBD_OBJ_WRITE_OBJECT;
3332 return false;
3333 case RBD_OBJ_WRITE_OBJECT:
3334 if (*result == -ENOENT) {
3335 if (obj_req->flags & RBD_OBJ_FLAG_COPYUP_ENABLED) {
3336 *result = 0;
3337 obj_req->copyup_state = RBD_OBJ_COPYUP_START;
3338 obj_req->write_state = __RBD_OBJ_WRITE_COPYUP;
3339 goto again;
3340 }
3341 /*
3342 * On a non-existent object:
3343 * delete - -ENOENT, truncate/zero - 0
3344 */
3345 if (obj_req->flags & RBD_OBJ_FLAG_DELETION)
3346 *result = 0;
3347 }
3348 if (*result)
3349 return true;
3350
3351 obj_req->write_state = RBD_OBJ_WRITE_COPYUP;
3352 goto again;
3353 case __RBD_OBJ_WRITE_COPYUP:
3354 if (!rbd_obj_advance_copyup(obj_req, result))
3355 return false;
3356 fallthrough;
3357 case RBD_OBJ_WRITE_COPYUP:
3358 if (*result) {
3359 rbd_warn(rbd_dev, "copyup failed: %d", *result);
3360 return true;
3361 }
3362 ret = rbd_obj_write_post_object_map(obj_req);
3363 if (ret < 0) {
3364 *result = ret;
3365 return true;
3366 }
3367 obj_req->write_state = RBD_OBJ_WRITE_POST_OBJECT_MAP;
3368 if (ret > 0)
3369 goto again;
3370 return false;
3371 case RBD_OBJ_WRITE_POST_OBJECT_MAP:
3372 if (*result)
3373 rbd_warn(rbd_dev, "post object map update failed: %d",
3374 *result);
3375 return true;
3376 default:
3377 BUG();
3378 }
3379}
3380
3381/*
3382 * Return true if @obj_req is completed.
3383 */
3384static bool __rbd_obj_handle_request(struct rbd_obj_request *obj_req,
3385 int *result)
3386{
3387 struct rbd_img_request *img_req = obj_req->img_request;
3388 struct rbd_device *rbd_dev = img_req->rbd_dev;
3389 bool done;
3390
3391 mutex_lock(&obj_req->state_mutex);
3392 if (!rbd_img_is_write(img_req))
3393 done = rbd_obj_advance_read(obj_req, result);
3394 else
3395 done = rbd_obj_advance_write(obj_req, result);
3396 mutex_unlock(&obj_req->state_mutex);
3397
3398 if (done && *result) {
3399 rbd_assert(*result < 0);
3400 rbd_warn(rbd_dev, "%s at objno %llu %llu~%llu result %d",
3401 obj_op_name(img_req->op_type), obj_req->ex.oe_objno,
3402 obj_req->ex.oe_off, obj_req->ex.oe_len, *result);
3403 }
3404 return done;
3405}
3406
3407/*
3408 * This is open-coded in rbd_img_handle_request() to avoid parent chain
3409 * recursion.
3410 */
3411static void rbd_obj_handle_request(struct rbd_obj_request *obj_req, int result)
3412{
3413 if (__rbd_obj_handle_request(obj_req, &result))
3414 rbd_img_handle_request(obj_req->img_request, result);
3415}
3416
3417static bool need_exclusive_lock(struct rbd_img_request *img_req)
3418{
3419 struct rbd_device *rbd_dev = img_req->rbd_dev;
3420
3421 if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK))
3422 return false;
3423
3424 if (rbd_is_ro(rbd_dev))
3425 return false;
3426
3427 rbd_assert(!test_bit(IMG_REQ_CHILD, &img_req->flags));
3428 if (rbd_dev->opts->lock_on_read ||
3429 (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP))
3430 return true;
3431
3432 return rbd_img_is_write(img_req);
3433}
3434
3435static bool rbd_lock_add_request(struct rbd_img_request *img_req)
3436{
3437 struct rbd_device *rbd_dev = img_req->rbd_dev;
3438 bool locked;
3439
3440 lockdep_assert_held(&rbd_dev->lock_rwsem);
3441 locked = rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED;
3442 spin_lock(&rbd_dev->lock_lists_lock);
3443 rbd_assert(list_empty(&img_req->lock_item));
3444 if (!locked)
3445 list_add_tail(&img_req->lock_item, &rbd_dev->acquiring_list);
3446 else
3447 list_add_tail(&img_req->lock_item, &rbd_dev->running_list);
3448 spin_unlock(&rbd_dev->lock_lists_lock);
3449 return locked;
3450}
3451
3452static void rbd_lock_del_request(struct rbd_img_request *img_req)
3453{
3454 struct rbd_device *rbd_dev = img_req->rbd_dev;
3455 bool need_wakeup = false;
3456
3457 lockdep_assert_held(&rbd_dev->lock_rwsem);
3458 spin_lock(&rbd_dev->lock_lists_lock);
3459 if (!list_empty(&img_req->lock_item)) {
3460 rbd_assert(!list_empty(&rbd_dev->running_list));
3461 list_del_init(&img_req->lock_item);
3462 need_wakeup = (rbd_dev->lock_state == RBD_LOCK_STATE_QUIESCING &&
3463 list_empty(&rbd_dev->running_list));
3464 }
3465 spin_unlock(&rbd_dev->lock_lists_lock);
3466 if (need_wakeup)
3467 complete(&rbd_dev->quiescing_wait);
3468}
3469
3470static int rbd_img_exclusive_lock(struct rbd_img_request *img_req)
3471{
3472 struct rbd_device *rbd_dev = img_req->rbd_dev;
3473
3474 if (!need_exclusive_lock(img_req))
3475 return 1;
3476
3477 if (rbd_lock_add_request(img_req))
3478 return 1;
3479
3480 /*
3481 * Note the use of mod_delayed_work() in rbd_acquire_lock()
3482 * and cancel_delayed_work() in wake_lock_waiters().
3483 */
3484 dout("%s rbd_dev %p queueing lock_dwork\n", __func__, rbd_dev);
3485 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
3486 return 0;
3487}
3488
3489static void rbd_img_object_requests(struct rbd_img_request *img_req)
3490{
3491 struct rbd_device *rbd_dev = img_req->rbd_dev;
3492 struct rbd_obj_request *obj_req;
3493
3494 rbd_assert(!img_req->pending.result && !img_req->pending.num_pending);
3495 rbd_assert(!need_exclusive_lock(img_req) ||
3496 __rbd_is_lock_owner(rbd_dev));
3497
3498 if (rbd_img_is_write(img_req)) {
3499 rbd_assert(!img_req->snapc);
3500 down_read(&rbd_dev->header_rwsem);
3501 img_req->snapc = ceph_get_snap_context(rbd_dev->header.snapc);
3502 up_read(&rbd_dev->header_rwsem);
3503 }
3504
3505 for_each_obj_request(img_req, obj_req) {
3506 int result = 0;
3507
3508 if (__rbd_obj_handle_request(obj_req, &result)) {
3509 if (result) {
3510 img_req->pending.result = result;
3511 return;
3512 }
3513 } else {
3514 img_req->pending.num_pending++;
3515 }
3516 }
3517}
3518
3519static bool rbd_img_advance(struct rbd_img_request *img_req, int *result)
3520{
3521 int ret;
3522
3523again:
3524 switch (img_req->state) {
3525 case RBD_IMG_START:
3526 rbd_assert(!*result);
3527
3528 ret = rbd_img_exclusive_lock(img_req);
3529 if (ret < 0) {
3530 *result = ret;
3531 return true;
3532 }
3533 img_req->state = RBD_IMG_EXCLUSIVE_LOCK;
3534 if (ret > 0)
3535 goto again;
3536 return false;
3537 case RBD_IMG_EXCLUSIVE_LOCK:
3538 if (*result)
3539 return true;
3540
3541 rbd_img_object_requests(img_req);
3542 if (!img_req->pending.num_pending) {
3543 *result = img_req->pending.result;
3544 img_req->state = RBD_IMG_OBJECT_REQUESTS;
3545 goto again;
3546 }
3547 img_req->state = __RBD_IMG_OBJECT_REQUESTS;
3548 return false;
3549 case __RBD_IMG_OBJECT_REQUESTS:
3550 if (!pending_result_dec(&img_req->pending, result))
3551 return false;
3552 fallthrough;
3553 case RBD_IMG_OBJECT_REQUESTS:
3554 return true;
3555 default:
3556 BUG();
3557 }
3558}
3559
3560/*
3561 * Return true if @img_req is completed.
3562 */
3563static bool __rbd_img_handle_request(struct rbd_img_request *img_req,
3564 int *result)
3565{
3566 struct rbd_device *rbd_dev = img_req->rbd_dev;
3567 bool done;
3568
3569 if (need_exclusive_lock(img_req)) {
3570 down_read(&rbd_dev->lock_rwsem);
3571 mutex_lock(&img_req->state_mutex);
3572 done = rbd_img_advance(img_req, result);
3573 if (done)
3574 rbd_lock_del_request(img_req);
3575 mutex_unlock(&img_req->state_mutex);
3576 up_read(&rbd_dev->lock_rwsem);
3577 } else {
3578 mutex_lock(&img_req->state_mutex);
3579 done = rbd_img_advance(img_req, result);
3580 mutex_unlock(&img_req->state_mutex);
3581 }
3582
3583 if (done && *result) {
3584 rbd_assert(*result < 0);
3585 rbd_warn(rbd_dev, "%s%s result %d",
3586 test_bit(IMG_REQ_CHILD, &img_req->flags) ? "child " : "",
3587 obj_op_name(img_req->op_type), *result);
3588 }
3589 return done;
3590}
3591
3592static void rbd_img_handle_request(struct rbd_img_request *img_req, int result)
3593{
3594again:
3595 if (!__rbd_img_handle_request(img_req, &result))
3596 return;
3597
3598 if (test_bit(IMG_REQ_CHILD, &img_req->flags)) {
3599 struct rbd_obj_request *obj_req = img_req->obj_request;
3600
3601 rbd_img_request_destroy(img_req);
3602 if (__rbd_obj_handle_request(obj_req, &result)) {
3603 img_req = obj_req->img_request;
3604 goto again;
3605 }
3606 } else {
3607 struct request *rq = blk_mq_rq_from_pdu(img_req);
3608
3609 rbd_img_request_destroy(img_req);
3610 blk_mq_end_request(rq, errno_to_blk_status(result));
3611 }
3612}
3613
3614static const struct rbd_client_id rbd_empty_cid;
3615
3616static bool rbd_cid_equal(const struct rbd_client_id *lhs,
3617 const struct rbd_client_id *rhs)
3618{
3619 return lhs->gid == rhs->gid && lhs->handle == rhs->handle;
3620}
3621
3622static struct rbd_client_id rbd_get_cid(struct rbd_device *rbd_dev)
3623{
3624 struct rbd_client_id cid;
3625
3626 mutex_lock(&rbd_dev->watch_mutex);
3627 cid.gid = ceph_client_gid(rbd_dev->rbd_client->client);
3628 cid.handle = rbd_dev->watch_cookie;
3629 mutex_unlock(&rbd_dev->watch_mutex);
3630 return cid;
3631}
3632
3633/*
3634 * lock_rwsem must be held for write
3635 */
3636static void rbd_set_owner_cid(struct rbd_device *rbd_dev,
3637 const struct rbd_client_id *cid)
3638{
3639 dout("%s rbd_dev %p %llu-%llu -> %llu-%llu\n", __func__, rbd_dev,
3640 rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle,
3641 cid->gid, cid->handle);
3642 rbd_dev->owner_cid = *cid; /* struct */
3643}
3644
3645static void format_lock_cookie(struct rbd_device *rbd_dev, char *buf)
3646{
3647 mutex_lock(&rbd_dev->watch_mutex);
3648 sprintf(buf, "%s %llu", RBD_LOCK_COOKIE_PREFIX, rbd_dev->watch_cookie);
3649 mutex_unlock(&rbd_dev->watch_mutex);
3650}
3651
3652static void __rbd_lock(struct rbd_device *rbd_dev, const char *cookie)
3653{
3654 struct rbd_client_id cid = rbd_get_cid(rbd_dev);
3655
3656 rbd_dev->lock_state = RBD_LOCK_STATE_LOCKED;
3657 strcpy(rbd_dev->lock_cookie, cookie);
3658 rbd_set_owner_cid(rbd_dev, &cid);
3659 queue_work(rbd_dev->task_wq, &rbd_dev->acquired_lock_work);
3660}
3661
3662/*
3663 * lock_rwsem must be held for write
3664 */
3665static int rbd_lock(struct rbd_device *rbd_dev)
3666{
3667 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3668 char cookie[32];
3669 int ret;
3670
3671 WARN_ON(__rbd_is_lock_owner(rbd_dev) ||
3672 rbd_dev->lock_cookie[0] != '\0');
3673
3674 format_lock_cookie(rbd_dev, cookie);
3675 ret = ceph_cls_lock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
3676 RBD_LOCK_NAME, CEPH_CLS_LOCK_EXCLUSIVE, cookie,
3677 RBD_LOCK_TAG, "", 0);
3678 if (ret && ret != -EEXIST)
3679 return ret;
3680
3681 __rbd_lock(rbd_dev, cookie);
3682 return 0;
3683}
3684
3685/*
3686 * lock_rwsem must be held for write
3687 */
3688static void rbd_unlock(struct rbd_device *rbd_dev)
3689{
3690 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3691 int ret;
3692
3693 WARN_ON(!__rbd_is_lock_owner(rbd_dev) ||
3694 rbd_dev->lock_cookie[0] == '\0');
3695
3696 ret = ceph_cls_unlock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
3697 RBD_LOCK_NAME, rbd_dev->lock_cookie);
3698 if (ret && ret != -ENOENT)
3699 rbd_warn(rbd_dev, "failed to unlock header: %d", ret);
3700
3701 /* treat errors as the image is unlocked */
3702 rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED;
3703 rbd_dev->lock_cookie[0] = '\0';
3704 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
3705 queue_work(rbd_dev->task_wq, &rbd_dev->released_lock_work);
3706}
3707
3708static int __rbd_notify_op_lock(struct rbd_device *rbd_dev,
3709 enum rbd_notify_op notify_op,
3710 struct page ***preply_pages,
3711 size_t *preply_len)
3712{
3713 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3714 struct rbd_client_id cid = rbd_get_cid(rbd_dev);
3715 char buf[4 + 8 + 8 + CEPH_ENCODING_START_BLK_LEN];
3716 int buf_size = sizeof(buf);
3717 void *p = buf;
3718
3719 dout("%s rbd_dev %p notify_op %d\n", __func__, rbd_dev, notify_op);
3720
3721 /* encode *LockPayload NotifyMessage (op + ClientId) */
3722 ceph_start_encoding(&p, 2, 1, buf_size - CEPH_ENCODING_START_BLK_LEN);
3723 ceph_encode_32(&p, notify_op);
3724 ceph_encode_64(&p, cid.gid);
3725 ceph_encode_64(&p, cid.handle);
3726
3727 return ceph_osdc_notify(osdc, &rbd_dev->header_oid,
3728 &rbd_dev->header_oloc, buf, buf_size,
3729 RBD_NOTIFY_TIMEOUT, preply_pages, preply_len);
3730}
3731
3732static void rbd_notify_op_lock(struct rbd_device *rbd_dev,
3733 enum rbd_notify_op notify_op)
3734{
3735 __rbd_notify_op_lock(rbd_dev, notify_op, NULL, NULL);
3736}
3737
3738static void rbd_notify_acquired_lock(struct work_struct *work)
3739{
3740 struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
3741 acquired_lock_work);
3742
3743 rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_ACQUIRED_LOCK);
3744}
3745
3746static void rbd_notify_released_lock(struct work_struct *work)
3747{
3748 struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
3749 released_lock_work);
3750
3751 rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_RELEASED_LOCK);
3752}
3753
3754static int rbd_request_lock(struct rbd_device *rbd_dev)
3755{
3756 struct page **reply_pages;
3757 size_t reply_len;
3758 bool lock_owner_responded = false;
3759 int ret;
3760
3761 dout("%s rbd_dev %p\n", __func__, rbd_dev);
3762
3763 ret = __rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_REQUEST_LOCK,
3764 &reply_pages, &reply_len);
3765 if (ret && ret != -ETIMEDOUT) {
3766 rbd_warn(rbd_dev, "failed to request lock: %d", ret);
3767 goto out;
3768 }
3769
3770 if (reply_len > 0 && reply_len <= PAGE_SIZE) {
3771 void *p = page_address(reply_pages[0]);
3772 void *const end = p + reply_len;
3773 u32 n;
3774
3775 ceph_decode_32_safe(&p, end, n, e_inval); /* num_acks */
3776 while (n--) {
3777 u8 struct_v;
3778 u32 len;
3779
3780 ceph_decode_need(&p, end, 8 + 8, e_inval);
3781 p += 8 + 8; /* skip gid and cookie */
3782
3783 ceph_decode_32_safe(&p, end, len, e_inval);
3784 if (!len)
3785 continue;
3786
3787 if (lock_owner_responded) {
3788 rbd_warn(rbd_dev,
3789 "duplicate lock owners detected");
3790 ret = -EIO;
3791 goto out;
3792 }
3793
3794 lock_owner_responded = true;
3795 ret = ceph_start_decoding(&p, end, 1, "ResponseMessage",
3796 &struct_v, &len);
3797 if (ret) {
3798 rbd_warn(rbd_dev,
3799 "failed to decode ResponseMessage: %d",
3800 ret);
3801 goto e_inval;
3802 }
3803
3804 ret = ceph_decode_32(&p);
3805 }
3806 }
3807
3808 if (!lock_owner_responded) {
3809 rbd_warn(rbd_dev, "no lock owners detected");
3810 ret = -ETIMEDOUT;
3811 }
3812
3813out:
3814 ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len));
3815 return ret;
3816
3817e_inval:
3818 ret = -EINVAL;
3819 goto out;
3820}
3821
3822/*
3823 * Either image request state machine(s) or rbd_add_acquire_lock()
3824 * (i.e. "rbd map").
3825 */
3826static void wake_lock_waiters(struct rbd_device *rbd_dev, int result)
3827{
3828 struct rbd_img_request *img_req;
3829
3830 dout("%s rbd_dev %p result %d\n", __func__, rbd_dev, result);
3831 lockdep_assert_held_write(&rbd_dev->lock_rwsem);
3832
3833 cancel_delayed_work(&rbd_dev->lock_dwork);
3834 if (!completion_done(&rbd_dev->acquire_wait)) {
3835 rbd_assert(list_empty(&rbd_dev->acquiring_list) &&
3836 list_empty(&rbd_dev->running_list));
3837 rbd_dev->acquire_err = result;
3838 complete_all(&rbd_dev->acquire_wait);
3839 return;
3840 }
3841
3842 while (!list_empty(&rbd_dev->acquiring_list)) {
3843 img_req = list_first_entry(&rbd_dev->acquiring_list,
3844 struct rbd_img_request, lock_item);
3845 mutex_lock(&img_req->state_mutex);
3846 rbd_assert(img_req->state == RBD_IMG_EXCLUSIVE_LOCK);
3847 if (!result)
3848 list_move_tail(&img_req->lock_item,
3849 &rbd_dev->running_list);
3850 else
3851 list_del_init(&img_req->lock_item);
3852 rbd_img_schedule(img_req, result);
3853 mutex_unlock(&img_req->state_mutex);
3854 }
3855}
3856
3857static bool locker_equal(const struct ceph_locker *lhs,
3858 const struct ceph_locker *rhs)
3859{
3860 return lhs->id.name.type == rhs->id.name.type &&
3861 lhs->id.name.num == rhs->id.name.num &&
3862 !strcmp(lhs->id.cookie, rhs->id.cookie) &&
3863 ceph_addr_equal_no_type(&lhs->info.addr, &rhs->info.addr);
3864}
3865
3866static void free_locker(struct ceph_locker *locker)
3867{
3868 if (locker)
3869 ceph_free_lockers(locker, 1);
3870}
3871
3872static struct ceph_locker *get_lock_owner_info(struct rbd_device *rbd_dev)
3873{
3874 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3875 struct ceph_locker *lockers;
3876 u32 num_lockers;
3877 u8 lock_type;
3878 char *lock_tag;
3879 u64 handle;
3880 int ret;
3881
3882 ret = ceph_cls_lock_info(osdc, &rbd_dev->header_oid,
3883 &rbd_dev->header_oloc, RBD_LOCK_NAME,
3884 &lock_type, &lock_tag, &lockers, &num_lockers);
3885 if (ret) {
3886 rbd_warn(rbd_dev, "failed to get header lockers: %d", ret);
3887 return ERR_PTR(ret);
3888 }
3889
3890 if (num_lockers == 0) {
3891 dout("%s rbd_dev %p no lockers detected\n", __func__, rbd_dev);
3892 lockers = NULL;
3893 goto out;
3894 }
3895
3896 if (strcmp(lock_tag, RBD_LOCK_TAG)) {
3897 rbd_warn(rbd_dev, "locked by external mechanism, tag %s",
3898 lock_tag);
3899 goto err_busy;
3900 }
3901
3902 if (lock_type != CEPH_CLS_LOCK_EXCLUSIVE) {
3903 rbd_warn(rbd_dev, "incompatible lock type detected");
3904 goto err_busy;
3905 }
3906
3907 WARN_ON(num_lockers != 1);
3908 ret = sscanf(lockers[0].id.cookie, RBD_LOCK_COOKIE_PREFIX " %llu",
3909 &handle);
3910 if (ret != 1) {
3911 rbd_warn(rbd_dev, "locked by external mechanism, cookie %s",
3912 lockers[0].id.cookie);
3913 goto err_busy;
3914 }
3915 if (ceph_addr_is_blank(&lockers[0].info.addr)) {
3916 rbd_warn(rbd_dev, "locker has a blank address");
3917 goto err_busy;
3918 }
3919
3920 dout("%s rbd_dev %p got locker %s%llu@%pISpc/%u handle %llu\n",
3921 __func__, rbd_dev, ENTITY_NAME(lockers[0].id.name),
3922 &lockers[0].info.addr.in_addr,
3923 le32_to_cpu(lockers[0].info.addr.nonce), handle);
3924
3925out:
3926 kfree(lock_tag);
3927 return lockers;
3928
3929err_busy:
3930 kfree(lock_tag);
3931 ceph_free_lockers(lockers, num_lockers);
3932 return ERR_PTR(-EBUSY);
3933}
3934
3935static int find_watcher(struct rbd_device *rbd_dev,
3936 const struct ceph_locker *locker)
3937{
3938 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3939 struct ceph_watch_item *watchers;
3940 u32 num_watchers;
3941 u64 cookie;
3942 int i;
3943 int ret;
3944
3945 ret = ceph_osdc_list_watchers(osdc, &rbd_dev->header_oid,
3946 &rbd_dev->header_oloc, &watchers,
3947 &num_watchers);
3948 if (ret) {
3949 rbd_warn(rbd_dev, "failed to get watchers: %d", ret);
3950 return ret;
3951 }
3952
3953 sscanf(locker->id.cookie, RBD_LOCK_COOKIE_PREFIX " %llu", &cookie);
3954 for (i = 0; i < num_watchers; i++) {
3955 /*
3956 * Ignore addr->type while comparing. This mimics
3957 * entity_addr_t::get_legacy_str() + strcmp().
3958 */
3959 if (ceph_addr_equal_no_type(&watchers[i].addr,
3960 &locker->info.addr) &&
3961 watchers[i].cookie == cookie) {
3962 struct rbd_client_id cid = {
3963 .gid = le64_to_cpu(watchers[i].name.num),
3964 .handle = cookie,
3965 };
3966
3967 dout("%s rbd_dev %p found cid %llu-%llu\n", __func__,
3968 rbd_dev, cid.gid, cid.handle);
3969 rbd_set_owner_cid(rbd_dev, &cid);
3970 ret = 1;
3971 goto out;
3972 }
3973 }
3974
3975 dout("%s rbd_dev %p no watchers\n", __func__, rbd_dev);
3976 ret = 0;
3977out:
3978 kfree(watchers);
3979 return ret;
3980}
3981
3982/*
3983 * lock_rwsem must be held for write
3984 */
3985static int rbd_try_lock(struct rbd_device *rbd_dev)
3986{
3987 struct ceph_client *client = rbd_dev->rbd_client->client;
3988 struct ceph_locker *locker, *refreshed_locker;
3989 int ret;
3990
3991 for (;;) {
3992 locker = refreshed_locker = NULL;
3993
3994 ret = rbd_lock(rbd_dev);
3995 if (!ret)
3996 goto out;
3997 if (ret != -EBUSY) {
3998 rbd_warn(rbd_dev, "failed to lock header: %d", ret);
3999 goto out;
4000 }
4001
4002 /* determine if the current lock holder is still alive */
4003 locker = get_lock_owner_info(rbd_dev);
4004 if (IS_ERR(locker)) {
4005 ret = PTR_ERR(locker);
4006 locker = NULL;
4007 goto out;
4008 }
4009 if (!locker)
4010 goto again;
4011
4012 ret = find_watcher(rbd_dev, locker);
4013 if (ret)
4014 goto out; /* request lock or error */
4015
4016 refreshed_locker = get_lock_owner_info(rbd_dev);
4017 if (IS_ERR(refreshed_locker)) {
4018 ret = PTR_ERR(refreshed_locker);
4019 refreshed_locker = NULL;
4020 goto out;
4021 }
4022 if (!refreshed_locker ||
4023 !locker_equal(locker, refreshed_locker))
4024 goto again;
4025
4026 rbd_warn(rbd_dev, "breaking header lock owned by %s%llu",
4027 ENTITY_NAME(locker->id.name));
4028
4029 ret = ceph_monc_blocklist_add(&client->monc,
4030 &locker->info.addr);
4031 if (ret) {
4032 rbd_warn(rbd_dev, "failed to blocklist %s%llu: %d",
4033 ENTITY_NAME(locker->id.name), ret);
4034 goto out;
4035 }
4036
4037 ret = ceph_cls_break_lock(&client->osdc, &rbd_dev->header_oid,
4038 &rbd_dev->header_oloc, RBD_LOCK_NAME,
4039 locker->id.cookie, &locker->id.name);
4040 if (ret && ret != -ENOENT) {
4041 rbd_warn(rbd_dev, "failed to break header lock: %d",
4042 ret);
4043 goto out;
4044 }
4045
4046again:
4047 free_locker(refreshed_locker);
4048 free_locker(locker);
4049 }
4050
4051out:
4052 free_locker(refreshed_locker);
4053 free_locker(locker);
4054 return ret;
4055}
4056
4057static int rbd_post_acquire_action(struct rbd_device *rbd_dev)
4058{
4059 int ret;
4060
4061 ret = rbd_dev_refresh(rbd_dev);
4062 if (ret)
4063 return ret;
4064
4065 if (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP) {
4066 ret = rbd_object_map_open(rbd_dev);
4067 if (ret)
4068 return ret;
4069 }
4070
4071 return 0;
4072}
4073
4074/*
4075 * Return:
4076 * 0 - lock acquired
4077 * 1 - caller should call rbd_request_lock()
4078 * <0 - error
4079 */
4080static int rbd_try_acquire_lock(struct rbd_device *rbd_dev)
4081{
4082 int ret;
4083
4084 down_read(&rbd_dev->lock_rwsem);
4085 dout("%s rbd_dev %p read lock_state %d\n", __func__, rbd_dev,
4086 rbd_dev->lock_state);
4087 if (__rbd_is_lock_owner(rbd_dev)) {
4088 up_read(&rbd_dev->lock_rwsem);
4089 return 0;
4090 }
4091
4092 up_read(&rbd_dev->lock_rwsem);
4093 down_write(&rbd_dev->lock_rwsem);
4094 dout("%s rbd_dev %p write lock_state %d\n", __func__, rbd_dev,
4095 rbd_dev->lock_state);
4096 if (__rbd_is_lock_owner(rbd_dev)) {
4097 up_write(&rbd_dev->lock_rwsem);
4098 return 0;
4099 }
4100
4101 ret = rbd_try_lock(rbd_dev);
4102 if (ret < 0) {
4103 rbd_warn(rbd_dev, "failed to acquire lock: %d", ret);
4104 goto out;
4105 }
4106 if (ret > 0) {
4107 up_write(&rbd_dev->lock_rwsem);
4108 return ret;
4109 }
4110
4111 rbd_assert(rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED);
4112 rbd_assert(list_empty(&rbd_dev->running_list));
4113
4114 ret = rbd_post_acquire_action(rbd_dev);
4115 if (ret) {
4116 rbd_warn(rbd_dev, "post-acquire action failed: %d", ret);
4117 /*
4118 * Can't stay in RBD_LOCK_STATE_LOCKED because
4119 * rbd_lock_add_request() would let the request through,
4120 * assuming that e.g. object map is locked and loaded.
4121 */
4122 rbd_unlock(rbd_dev);
4123 }
4124
4125out:
4126 wake_lock_waiters(rbd_dev, ret);
4127 up_write(&rbd_dev->lock_rwsem);
4128 return ret;
4129}
4130
4131static void rbd_acquire_lock(struct work_struct *work)
4132{
4133 struct rbd_device *rbd_dev = container_of(to_delayed_work(work),
4134 struct rbd_device, lock_dwork);
4135 int ret;
4136
4137 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4138again:
4139 ret = rbd_try_acquire_lock(rbd_dev);
4140 if (ret <= 0) {
4141 dout("%s rbd_dev %p ret %d - done\n", __func__, rbd_dev, ret);
4142 return;
4143 }
4144
4145 ret = rbd_request_lock(rbd_dev);
4146 if (ret == -ETIMEDOUT) {
4147 goto again; /* treat this as a dead client */
4148 } else if (ret == -EROFS) {
4149 rbd_warn(rbd_dev, "peer will not release lock");
4150 down_write(&rbd_dev->lock_rwsem);
4151 wake_lock_waiters(rbd_dev, ret);
4152 up_write(&rbd_dev->lock_rwsem);
4153 } else if (ret < 0) {
4154 rbd_warn(rbd_dev, "error requesting lock: %d", ret);
4155 mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
4156 RBD_RETRY_DELAY);
4157 } else {
4158 /*
4159 * lock owner acked, but resend if we don't see them
4160 * release the lock
4161 */
4162 dout("%s rbd_dev %p requeuing lock_dwork\n", __func__,
4163 rbd_dev);
4164 mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
4165 msecs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT * MSEC_PER_SEC));
4166 }
4167}
4168
4169static bool rbd_quiesce_lock(struct rbd_device *rbd_dev)
4170{
4171 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4172 lockdep_assert_held_write(&rbd_dev->lock_rwsem);
4173
4174 if (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED)
4175 return false;
4176
4177 /*
4178 * Ensure that all in-flight IO is flushed.
4179 */
4180 rbd_dev->lock_state = RBD_LOCK_STATE_QUIESCING;
4181 rbd_assert(!completion_done(&rbd_dev->quiescing_wait));
4182 if (list_empty(&rbd_dev->running_list))
4183 return true;
4184
4185 up_write(&rbd_dev->lock_rwsem);
4186 wait_for_completion(&rbd_dev->quiescing_wait);
4187
4188 down_write(&rbd_dev->lock_rwsem);
4189 if (rbd_dev->lock_state != RBD_LOCK_STATE_QUIESCING)
4190 return false;
4191
4192 rbd_assert(list_empty(&rbd_dev->running_list));
4193 return true;
4194}
4195
4196static void rbd_pre_release_action(struct rbd_device *rbd_dev)
4197{
4198 if (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP)
4199 rbd_object_map_close(rbd_dev);
4200}
4201
4202static void __rbd_release_lock(struct rbd_device *rbd_dev)
4203{
4204 rbd_assert(list_empty(&rbd_dev->running_list));
4205
4206 rbd_pre_release_action(rbd_dev);
4207 rbd_unlock(rbd_dev);
4208}
4209
4210/*
4211 * lock_rwsem must be held for write
4212 */
4213static void rbd_release_lock(struct rbd_device *rbd_dev)
4214{
4215 if (!rbd_quiesce_lock(rbd_dev))
4216 return;
4217
4218 __rbd_release_lock(rbd_dev);
4219
4220 /*
4221 * Give others a chance to grab the lock - we would re-acquire
4222 * almost immediately if we got new IO while draining the running
4223 * list otherwise. We need to ack our own notifications, so this
4224 * lock_dwork will be requeued from rbd_handle_released_lock() by
4225 * way of maybe_kick_acquire().
4226 */
4227 cancel_delayed_work(&rbd_dev->lock_dwork);
4228}
4229
4230static void rbd_release_lock_work(struct work_struct *work)
4231{
4232 struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
4233 unlock_work);
4234
4235 down_write(&rbd_dev->lock_rwsem);
4236 rbd_release_lock(rbd_dev);
4237 up_write(&rbd_dev->lock_rwsem);
4238}
4239
4240static void maybe_kick_acquire(struct rbd_device *rbd_dev)
4241{
4242 bool have_requests;
4243
4244 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4245 if (__rbd_is_lock_owner(rbd_dev))
4246 return;
4247
4248 spin_lock(&rbd_dev->lock_lists_lock);
4249 have_requests = !list_empty(&rbd_dev->acquiring_list);
4250 spin_unlock(&rbd_dev->lock_lists_lock);
4251 if (have_requests || delayed_work_pending(&rbd_dev->lock_dwork)) {
4252 dout("%s rbd_dev %p kicking lock_dwork\n", __func__, rbd_dev);
4253 mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
4254 }
4255}
4256
4257static void rbd_handle_acquired_lock(struct rbd_device *rbd_dev, u8 struct_v,
4258 void **p)
4259{
4260 struct rbd_client_id cid = { 0 };
4261
4262 if (struct_v >= 2) {
4263 cid.gid = ceph_decode_64(p);
4264 cid.handle = ceph_decode_64(p);
4265 }
4266
4267 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
4268 cid.handle);
4269 if (!rbd_cid_equal(&cid, &rbd_empty_cid)) {
4270 down_write(&rbd_dev->lock_rwsem);
4271 if (rbd_cid_equal(&cid, &rbd_dev->owner_cid)) {
4272 dout("%s rbd_dev %p cid %llu-%llu == owner_cid\n",
4273 __func__, rbd_dev, cid.gid, cid.handle);
4274 } else {
4275 rbd_set_owner_cid(rbd_dev, &cid);
4276 }
4277 downgrade_write(&rbd_dev->lock_rwsem);
4278 } else {
4279 down_read(&rbd_dev->lock_rwsem);
4280 }
4281
4282 maybe_kick_acquire(rbd_dev);
4283 up_read(&rbd_dev->lock_rwsem);
4284}
4285
4286static void rbd_handle_released_lock(struct rbd_device *rbd_dev, u8 struct_v,
4287 void **p)
4288{
4289 struct rbd_client_id cid = { 0 };
4290
4291 if (struct_v >= 2) {
4292 cid.gid = ceph_decode_64(p);
4293 cid.handle = ceph_decode_64(p);
4294 }
4295
4296 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
4297 cid.handle);
4298 if (!rbd_cid_equal(&cid, &rbd_empty_cid)) {
4299 down_write(&rbd_dev->lock_rwsem);
4300 if (!rbd_cid_equal(&cid, &rbd_dev->owner_cid)) {
4301 dout("%s rbd_dev %p cid %llu-%llu != owner_cid %llu-%llu\n",
4302 __func__, rbd_dev, cid.gid, cid.handle,
4303 rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle);
4304 } else {
4305 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
4306 }
4307 downgrade_write(&rbd_dev->lock_rwsem);
4308 } else {
4309 down_read(&rbd_dev->lock_rwsem);
4310 }
4311
4312 maybe_kick_acquire(rbd_dev);
4313 up_read(&rbd_dev->lock_rwsem);
4314}
4315
4316/*
4317 * Returns result for ResponseMessage to be encoded (<= 0), or 1 if no
4318 * ResponseMessage is needed.
4319 */
4320static int rbd_handle_request_lock(struct rbd_device *rbd_dev, u8 struct_v,
4321 void **p)
4322{
4323 struct rbd_client_id my_cid = rbd_get_cid(rbd_dev);
4324 struct rbd_client_id cid = { 0 };
4325 int result = 1;
4326
4327 if (struct_v >= 2) {
4328 cid.gid = ceph_decode_64(p);
4329 cid.handle = ceph_decode_64(p);
4330 }
4331
4332 dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
4333 cid.handle);
4334 if (rbd_cid_equal(&cid, &my_cid))
4335 return result;
4336
4337 down_read(&rbd_dev->lock_rwsem);
4338 if (__rbd_is_lock_owner(rbd_dev)) {
4339 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED &&
4340 rbd_cid_equal(&rbd_dev->owner_cid, &rbd_empty_cid))
4341 goto out_unlock;
4342
4343 /*
4344 * encode ResponseMessage(0) so the peer can detect
4345 * a missing owner
4346 */
4347 result = 0;
4348
4349 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED) {
4350 if (!rbd_dev->opts->exclusive) {
4351 dout("%s rbd_dev %p queueing unlock_work\n",
4352 __func__, rbd_dev);
4353 queue_work(rbd_dev->task_wq,
4354 &rbd_dev->unlock_work);
4355 } else {
4356 /* refuse to release the lock */
4357 result = -EROFS;
4358 }
4359 }
4360 }
4361
4362out_unlock:
4363 up_read(&rbd_dev->lock_rwsem);
4364 return result;
4365}
4366
4367static void __rbd_acknowledge_notify(struct rbd_device *rbd_dev,
4368 u64 notify_id, u64 cookie, s32 *result)
4369{
4370 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4371 char buf[4 + CEPH_ENCODING_START_BLK_LEN];
4372 int buf_size = sizeof(buf);
4373 int ret;
4374
4375 if (result) {
4376 void *p = buf;
4377
4378 /* encode ResponseMessage */
4379 ceph_start_encoding(&p, 1, 1,
4380 buf_size - CEPH_ENCODING_START_BLK_LEN);
4381 ceph_encode_32(&p, *result);
4382 } else {
4383 buf_size = 0;
4384 }
4385
4386 ret = ceph_osdc_notify_ack(osdc, &rbd_dev->header_oid,
4387 &rbd_dev->header_oloc, notify_id, cookie,
4388 buf, buf_size);
4389 if (ret)
4390 rbd_warn(rbd_dev, "acknowledge_notify failed: %d", ret);
4391}
4392
4393static void rbd_acknowledge_notify(struct rbd_device *rbd_dev, u64 notify_id,
4394 u64 cookie)
4395{
4396 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4397 __rbd_acknowledge_notify(rbd_dev, notify_id, cookie, NULL);
4398}
4399
4400static void rbd_acknowledge_notify_result(struct rbd_device *rbd_dev,
4401 u64 notify_id, u64 cookie, s32 result)
4402{
4403 dout("%s rbd_dev %p result %d\n", __func__, rbd_dev, result);
4404 __rbd_acknowledge_notify(rbd_dev, notify_id, cookie, &result);
4405}
4406
4407static void rbd_watch_cb(void *arg, u64 notify_id, u64 cookie,
4408 u64 notifier_id, void *data, size_t data_len)
4409{
4410 struct rbd_device *rbd_dev = arg;
4411 void *p = data;
4412 void *const end = p + data_len;
4413 u8 struct_v = 0;
4414 u32 len;
4415 u32 notify_op;
4416 int ret;
4417
4418 dout("%s rbd_dev %p cookie %llu notify_id %llu data_len %zu\n",
4419 __func__, rbd_dev, cookie, notify_id, data_len);
4420 if (data_len) {
4421 ret = ceph_start_decoding(&p, end, 1, "NotifyMessage",
4422 &struct_v, &len);
4423 if (ret) {
4424 rbd_warn(rbd_dev, "failed to decode NotifyMessage: %d",
4425 ret);
4426 return;
4427 }
4428
4429 notify_op = ceph_decode_32(&p);
4430 } else {
4431 /* legacy notification for header updates */
4432 notify_op = RBD_NOTIFY_OP_HEADER_UPDATE;
4433 len = 0;
4434 }
4435
4436 dout("%s rbd_dev %p notify_op %u\n", __func__, rbd_dev, notify_op);
4437 switch (notify_op) {
4438 case RBD_NOTIFY_OP_ACQUIRED_LOCK:
4439 rbd_handle_acquired_lock(rbd_dev, struct_v, &p);
4440 rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4441 break;
4442 case RBD_NOTIFY_OP_RELEASED_LOCK:
4443 rbd_handle_released_lock(rbd_dev, struct_v, &p);
4444 rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4445 break;
4446 case RBD_NOTIFY_OP_REQUEST_LOCK:
4447 ret = rbd_handle_request_lock(rbd_dev, struct_v, &p);
4448 if (ret <= 0)
4449 rbd_acknowledge_notify_result(rbd_dev, notify_id,
4450 cookie, ret);
4451 else
4452 rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4453 break;
4454 case RBD_NOTIFY_OP_HEADER_UPDATE:
4455 ret = rbd_dev_refresh(rbd_dev);
4456 if (ret)
4457 rbd_warn(rbd_dev, "refresh failed: %d", ret);
4458
4459 rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4460 break;
4461 default:
4462 if (rbd_is_lock_owner(rbd_dev))
4463 rbd_acknowledge_notify_result(rbd_dev, notify_id,
4464 cookie, -EOPNOTSUPP);
4465 else
4466 rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
4467 break;
4468 }
4469}
4470
4471static void __rbd_unregister_watch(struct rbd_device *rbd_dev);
4472
4473static void rbd_watch_errcb(void *arg, u64 cookie, int err)
4474{
4475 struct rbd_device *rbd_dev = arg;
4476
4477 rbd_warn(rbd_dev, "encountered watch error: %d", err);
4478
4479 down_write(&rbd_dev->lock_rwsem);
4480 rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
4481 up_write(&rbd_dev->lock_rwsem);
4482
4483 mutex_lock(&rbd_dev->watch_mutex);
4484 if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED) {
4485 __rbd_unregister_watch(rbd_dev);
4486 rbd_dev->watch_state = RBD_WATCH_STATE_ERROR;
4487
4488 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->watch_dwork, 0);
4489 }
4490 mutex_unlock(&rbd_dev->watch_mutex);
4491}
4492
4493/*
4494 * watch_mutex must be locked
4495 */
4496static int __rbd_register_watch(struct rbd_device *rbd_dev)
4497{
4498 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4499 struct ceph_osd_linger_request *handle;
4500
4501 rbd_assert(!rbd_dev->watch_handle);
4502 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4503
4504 handle = ceph_osdc_watch(osdc, &rbd_dev->header_oid,
4505 &rbd_dev->header_oloc, rbd_watch_cb,
4506 rbd_watch_errcb, rbd_dev);
4507 if (IS_ERR(handle))
4508 return PTR_ERR(handle);
4509
4510 rbd_dev->watch_handle = handle;
4511 return 0;
4512}
4513
4514/*
4515 * watch_mutex must be locked
4516 */
4517static void __rbd_unregister_watch(struct rbd_device *rbd_dev)
4518{
4519 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4520 int ret;
4521
4522 rbd_assert(rbd_dev->watch_handle);
4523 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4524
4525 ret = ceph_osdc_unwatch(osdc, rbd_dev->watch_handle);
4526 if (ret)
4527 rbd_warn(rbd_dev, "failed to unwatch: %d", ret);
4528
4529 rbd_dev->watch_handle = NULL;
4530}
4531
4532static int rbd_register_watch(struct rbd_device *rbd_dev)
4533{
4534 int ret;
4535
4536 mutex_lock(&rbd_dev->watch_mutex);
4537 rbd_assert(rbd_dev->watch_state == RBD_WATCH_STATE_UNREGISTERED);
4538 ret = __rbd_register_watch(rbd_dev);
4539 if (ret)
4540 goto out;
4541
4542 rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED;
4543 rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id;
4544
4545out:
4546 mutex_unlock(&rbd_dev->watch_mutex);
4547 return ret;
4548}
4549
4550static void cancel_tasks_sync(struct rbd_device *rbd_dev)
4551{
4552 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4553
4554 cancel_work_sync(&rbd_dev->acquired_lock_work);
4555 cancel_work_sync(&rbd_dev->released_lock_work);
4556 cancel_delayed_work_sync(&rbd_dev->lock_dwork);
4557 cancel_work_sync(&rbd_dev->unlock_work);
4558}
4559
4560/*
4561 * header_rwsem must not be held to avoid a deadlock with
4562 * rbd_dev_refresh() when flushing notifies.
4563 */
4564static void rbd_unregister_watch(struct rbd_device *rbd_dev)
4565{
4566 cancel_tasks_sync(rbd_dev);
4567
4568 mutex_lock(&rbd_dev->watch_mutex);
4569 if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED)
4570 __rbd_unregister_watch(rbd_dev);
4571 rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED;
4572 mutex_unlock(&rbd_dev->watch_mutex);
4573
4574 cancel_delayed_work_sync(&rbd_dev->watch_dwork);
4575 ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc);
4576}
4577
4578/*
4579 * lock_rwsem must be held for write
4580 */
4581static void rbd_reacquire_lock(struct rbd_device *rbd_dev)
4582{
4583 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4584 char cookie[32];
4585 int ret;
4586
4587 if (!rbd_quiesce_lock(rbd_dev))
4588 return;
4589
4590 format_lock_cookie(rbd_dev, cookie);
4591 ret = ceph_cls_set_cookie(osdc, &rbd_dev->header_oid,
4592 &rbd_dev->header_oloc, RBD_LOCK_NAME,
4593 CEPH_CLS_LOCK_EXCLUSIVE, rbd_dev->lock_cookie,
4594 RBD_LOCK_TAG, cookie);
4595 if (ret) {
4596 if (ret != -EOPNOTSUPP)
4597 rbd_warn(rbd_dev, "failed to update lock cookie: %d",
4598 ret);
4599
4600 if (rbd_dev->opts->exclusive)
4601 rbd_warn(rbd_dev,
4602 "temporarily releasing lock on exclusive mapping");
4603
4604 /*
4605 * Lock cookie cannot be updated on older OSDs, so do
4606 * a manual release and queue an acquire.
4607 */
4608 __rbd_release_lock(rbd_dev);
4609 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
4610 } else {
4611 __rbd_lock(rbd_dev, cookie);
4612 wake_lock_waiters(rbd_dev, 0);
4613 }
4614}
4615
4616static void rbd_reregister_watch(struct work_struct *work)
4617{
4618 struct rbd_device *rbd_dev = container_of(to_delayed_work(work),
4619 struct rbd_device, watch_dwork);
4620 int ret;
4621
4622 dout("%s rbd_dev %p\n", __func__, rbd_dev);
4623
4624 mutex_lock(&rbd_dev->watch_mutex);
4625 if (rbd_dev->watch_state != RBD_WATCH_STATE_ERROR) {
4626 mutex_unlock(&rbd_dev->watch_mutex);
4627 return;
4628 }
4629
4630 ret = __rbd_register_watch(rbd_dev);
4631 if (ret) {
4632 rbd_warn(rbd_dev, "failed to reregister watch: %d", ret);
4633 if (ret != -EBLOCKLISTED && ret != -ENOENT) {
4634 queue_delayed_work(rbd_dev->task_wq,
4635 &rbd_dev->watch_dwork,
4636 RBD_RETRY_DELAY);
4637 mutex_unlock(&rbd_dev->watch_mutex);
4638 return;
4639 }
4640
4641 mutex_unlock(&rbd_dev->watch_mutex);
4642 down_write(&rbd_dev->lock_rwsem);
4643 wake_lock_waiters(rbd_dev, ret);
4644 up_write(&rbd_dev->lock_rwsem);
4645 return;
4646 }
4647
4648 rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED;
4649 rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id;
4650 mutex_unlock(&rbd_dev->watch_mutex);
4651
4652 down_write(&rbd_dev->lock_rwsem);
4653 if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED)
4654 rbd_reacquire_lock(rbd_dev);
4655 up_write(&rbd_dev->lock_rwsem);
4656
4657 ret = rbd_dev_refresh(rbd_dev);
4658 if (ret)
4659 rbd_warn(rbd_dev, "reregistration refresh failed: %d", ret);
4660}
4661
4662/*
4663 * Synchronous osd object method call. Returns the number of bytes
4664 * returned in the outbound buffer, or a negative error code.
4665 */
4666static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
4667 struct ceph_object_id *oid,
4668 struct ceph_object_locator *oloc,
4669 const char *method_name,
4670 const void *outbound,
4671 size_t outbound_size,
4672 void *inbound,
4673 size_t inbound_size)
4674{
4675 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4676 struct page *req_page = NULL;
4677 struct page *reply_page;
4678 int ret;
4679
4680 /*
4681 * Method calls are ultimately read operations. The result
4682 * should placed into the inbound buffer provided. They
4683 * also supply outbound data--parameters for the object
4684 * method. Currently if this is present it will be a
4685 * snapshot id.
4686 */
4687 if (outbound) {
4688 if (outbound_size > PAGE_SIZE)
4689 return -E2BIG;
4690
4691 req_page = alloc_page(GFP_KERNEL);
4692 if (!req_page)
4693 return -ENOMEM;
4694
4695 memcpy(page_address(req_page), outbound, outbound_size);
4696 }
4697
4698 reply_page = alloc_page(GFP_KERNEL);
4699 if (!reply_page) {
4700 if (req_page)
4701 __free_page(req_page);
4702 return -ENOMEM;
4703 }
4704
4705 ret = ceph_osdc_call(osdc, oid, oloc, RBD_DRV_NAME, method_name,
4706 CEPH_OSD_FLAG_READ, req_page, outbound_size,
4707 &reply_page, &inbound_size);
4708 if (!ret) {
4709 memcpy(inbound, page_address(reply_page), inbound_size);
4710 ret = inbound_size;
4711 }
4712
4713 if (req_page)
4714 __free_page(req_page);
4715 __free_page(reply_page);
4716 return ret;
4717}
4718
4719static void rbd_queue_workfn(struct work_struct *work)
4720{
4721 struct rbd_img_request *img_request =
4722 container_of(work, struct rbd_img_request, work);
4723 struct rbd_device *rbd_dev = img_request->rbd_dev;
4724 enum obj_operation_type op_type = img_request->op_type;
4725 struct request *rq = blk_mq_rq_from_pdu(img_request);
4726 u64 offset = (u64)blk_rq_pos(rq) << SECTOR_SHIFT;
4727 u64 length = blk_rq_bytes(rq);
4728 u64 mapping_size;
4729 int result;
4730
4731 /* Ignore/skip any zero-length requests */
4732 if (!length) {
4733 dout("%s: zero-length request\n", __func__);
4734 result = 0;
4735 goto err_img_request;
4736 }
4737
4738 blk_mq_start_request(rq);
4739
4740 down_read(&rbd_dev->header_rwsem);
4741 mapping_size = rbd_dev->mapping.size;
4742 rbd_img_capture_header(img_request);
4743 up_read(&rbd_dev->header_rwsem);
4744
4745 if (offset + length > mapping_size) {
4746 rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)", offset,
4747 length, mapping_size);
4748 result = -EIO;
4749 goto err_img_request;
4750 }
4751
4752 dout("%s rbd_dev %p img_req %p %s %llu~%llu\n", __func__, rbd_dev,
4753 img_request, obj_op_name(op_type), offset, length);
4754
4755 if (op_type == OBJ_OP_DISCARD || op_type == OBJ_OP_ZEROOUT)
4756 result = rbd_img_fill_nodata(img_request, offset, length);
4757 else
4758 result = rbd_img_fill_from_bio(img_request, offset, length,
4759 rq->bio);
4760 if (result)
4761 goto err_img_request;
4762
4763 rbd_img_handle_request(img_request, 0);
4764 return;
4765
4766err_img_request:
4767 rbd_img_request_destroy(img_request);
4768 if (result)
4769 rbd_warn(rbd_dev, "%s %llx at %llx result %d",
4770 obj_op_name(op_type), length, offset, result);
4771 blk_mq_end_request(rq, errno_to_blk_status(result));
4772}
4773
4774static blk_status_t rbd_queue_rq(struct blk_mq_hw_ctx *hctx,
4775 const struct blk_mq_queue_data *bd)
4776{
4777 struct rbd_device *rbd_dev = hctx->queue->queuedata;
4778 struct rbd_img_request *img_req = blk_mq_rq_to_pdu(bd->rq);
4779 enum obj_operation_type op_type;
4780
4781 switch (req_op(bd->rq)) {
4782 case REQ_OP_DISCARD:
4783 op_type = OBJ_OP_DISCARD;
4784 break;
4785 case REQ_OP_WRITE_ZEROES:
4786 op_type = OBJ_OP_ZEROOUT;
4787 break;
4788 case REQ_OP_WRITE:
4789 op_type = OBJ_OP_WRITE;
4790 break;
4791 case REQ_OP_READ:
4792 op_type = OBJ_OP_READ;
4793 break;
4794 default:
4795 rbd_warn(rbd_dev, "unknown req_op %d", req_op(bd->rq));
4796 return BLK_STS_IOERR;
4797 }
4798
4799 rbd_img_request_init(img_req, rbd_dev, op_type);
4800
4801 if (rbd_img_is_write(img_req)) {
4802 if (rbd_is_ro(rbd_dev)) {
4803 rbd_warn(rbd_dev, "%s on read-only mapping",
4804 obj_op_name(img_req->op_type));
4805 return BLK_STS_IOERR;
4806 }
4807 rbd_assert(!rbd_is_snap(rbd_dev));
4808 }
4809
4810 INIT_WORK(&img_req->work, rbd_queue_workfn);
4811 queue_work(rbd_wq, &img_req->work);
4812 return BLK_STS_OK;
4813}
4814
4815static void rbd_free_disk(struct rbd_device *rbd_dev)
4816{
4817 put_disk(rbd_dev->disk);
4818 blk_mq_free_tag_set(&rbd_dev->tag_set);
4819 rbd_dev->disk = NULL;
4820}
4821
4822static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
4823 struct ceph_object_id *oid,
4824 struct ceph_object_locator *oloc,
4825 void *buf, int buf_len)
4826
4827{
4828 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4829 struct ceph_osd_request *req;
4830 struct page **pages;
4831 int num_pages = calc_pages_for(0, buf_len);
4832 int ret;
4833
4834 req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_KERNEL);
4835 if (!req)
4836 return -ENOMEM;
4837
4838 ceph_oid_copy(&req->r_base_oid, oid);
4839 ceph_oloc_copy(&req->r_base_oloc, oloc);
4840 req->r_flags = CEPH_OSD_FLAG_READ;
4841
4842 pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
4843 if (IS_ERR(pages)) {
4844 ret = PTR_ERR(pages);
4845 goto out_req;
4846 }
4847
4848 osd_req_op_extent_init(req, 0, CEPH_OSD_OP_READ, 0, buf_len, 0, 0);
4849 osd_req_op_extent_osd_data_pages(req, 0, pages, buf_len, 0, false,
4850 true);
4851
4852 ret = ceph_osdc_alloc_messages(req, GFP_KERNEL);
4853 if (ret)
4854 goto out_req;
4855
4856 ceph_osdc_start_request(osdc, req);
4857 ret = ceph_osdc_wait_request(osdc, req);
4858 if (ret >= 0)
4859 ceph_copy_from_page_vector(pages, buf, 0, ret);
4860
4861out_req:
4862 ceph_osdc_put_request(req);
4863 return ret;
4864}
4865
4866/*
4867 * Read the complete header for the given rbd device. On successful
4868 * return, the rbd_dev->header field will contain up-to-date
4869 * information about the image.
4870 */
4871static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev,
4872 struct rbd_image_header *header,
4873 bool first_time)
4874{
4875 struct rbd_image_header_ondisk *ondisk = NULL;
4876 u32 snap_count = 0;
4877 u64 names_size = 0;
4878 u32 want_count;
4879 int ret;
4880
4881 /*
4882 * The complete header will include an array of its 64-bit
4883 * snapshot ids, followed by the names of those snapshots as
4884 * a contiguous block of NUL-terminated strings. Note that
4885 * the number of snapshots could change by the time we read
4886 * it in, in which case we re-read it.
4887 */
4888 do {
4889 size_t size;
4890
4891 kfree(ondisk);
4892
4893 size = sizeof (*ondisk);
4894 size += snap_count * sizeof (struct rbd_image_snap_ondisk);
4895 size += names_size;
4896 ondisk = kmalloc(size, GFP_KERNEL);
4897 if (!ondisk)
4898 return -ENOMEM;
4899
4900 ret = rbd_obj_read_sync(rbd_dev, &rbd_dev->header_oid,
4901 &rbd_dev->header_oloc, ondisk, size);
4902 if (ret < 0)
4903 goto out;
4904 if ((size_t)ret < size) {
4905 ret = -ENXIO;
4906 rbd_warn(rbd_dev, "short header read (want %zd got %d)",
4907 size, ret);
4908 goto out;
4909 }
4910 if (!rbd_dev_ondisk_valid(ondisk)) {
4911 ret = -ENXIO;
4912 rbd_warn(rbd_dev, "invalid header");
4913 goto out;
4914 }
4915
4916 names_size = le64_to_cpu(ondisk->snap_names_len);
4917 want_count = snap_count;
4918 snap_count = le32_to_cpu(ondisk->snap_count);
4919 } while (snap_count != want_count);
4920
4921 ret = rbd_header_from_disk(header, ondisk, first_time);
4922out:
4923 kfree(ondisk);
4924
4925 return ret;
4926}
4927
4928static void rbd_dev_update_size(struct rbd_device *rbd_dev)
4929{
4930 sector_t size;
4931
4932 /*
4933 * If EXISTS is not set, rbd_dev->disk may be NULL, so don't
4934 * try to update its size. If REMOVING is set, updating size
4935 * is just useless work since the device can't be opened.
4936 */
4937 if (test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags) &&
4938 !test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) {
4939 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
4940 dout("setting size to %llu sectors", (unsigned long long)size);
4941 set_capacity_and_notify(rbd_dev->disk, size);
4942 }
4943}
4944
4945static const struct blk_mq_ops rbd_mq_ops = {
4946 .queue_rq = rbd_queue_rq,
4947};
4948
4949static int rbd_init_disk(struct rbd_device *rbd_dev)
4950{
4951 struct gendisk *disk;
4952 unsigned int objset_bytes =
4953 rbd_dev->layout.object_size * rbd_dev->layout.stripe_count;
4954 struct queue_limits lim = {
4955 .max_hw_sectors = objset_bytes >> SECTOR_SHIFT,
4956 .io_opt = objset_bytes,
4957 .io_min = rbd_dev->opts->alloc_size,
4958 .max_segments = USHRT_MAX,
4959 .max_segment_size = UINT_MAX,
4960 };
4961 int err;
4962
4963 memset(&rbd_dev->tag_set, 0, sizeof(rbd_dev->tag_set));
4964 rbd_dev->tag_set.ops = &rbd_mq_ops;
4965 rbd_dev->tag_set.queue_depth = rbd_dev->opts->queue_depth;
4966 rbd_dev->tag_set.numa_node = NUMA_NO_NODE;
4967 rbd_dev->tag_set.nr_hw_queues = num_present_cpus();
4968 rbd_dev->tag_set.cmd_size = sizeof(struct rbd_img_request);
4969
4970 err = blk_mq_alloc_tag_set(&rbd_dev->tag_set);
4971 if (err)
4972 return err;
4973
4974 if (rbd_dev->opts->trim) {
4975 lim.discard_granularity = rbd_dev->opts->alloc_size;
4976 lim.max_hw_discard_sectors = objset_bytes >> SECTOR_SHIFT;
4977 lim.max_write_zeroes_sectors = objset_bytes >> SECTOR_SHIFT;
4978 }
4979
4980 if (!ceph_test_opt(rbd_dev->rbd_client->client, NOCRC))
4981 lim.features |= BLK_FEAT_STABLE_WRITES;
4982
4983 disk = blk_mq_alloc_disk(&rbd_dev->tag_set, &lim, rbd_dev);
4984 if (IS_ERR(disk)) {
4985 err = PTR_ERR(disk);
4986 goto out_tag_set;
4987 }
4988
4989 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
4990 rbd_dev->dev_id);
4991 disk->major = rbd_dev->major;
4992 disk->first_minor = rbd_dev->minor;
4993 if (single_major)
4994 disk->minors = (1 << RBD_SINGLE_MAJOR_PART_SHIFT);
4995 else
4996 disk->minors = RBD_MINORS_PER_MAJOR;
4997 disk->fops = &rbd_bd_ops;
4998 disk->private_data = rbd_dev;
4999 rbd_dev->disk = disk;
5000
5001 return 0;
5002out_tag_set:
5003 blk_mq_free_tag_set(&rbd_dev->tag_set);
5004 return err;
5005}
5006
5007/*
5008 sysfs
5009*/
5010
5011static struct rbd_device *dev_to_rbd_dev(struct device *dev)
5012{
5013 return container_of(dev, struct rbd_device, dev);
5014}
5015
5016static ssize_t rbd_size_show(struct device *dev,
5017 struct device_attribute *attr, char *buf)
5018{
5019 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5020
5021 return sprintf(buf, "%llu\n",
5022 (unsigned long long)rbd_dev->mapping.size);
5023}
5024
5025static ssize_t rbd_features_show(struct device *dev,
5026 struct device_attribute *attr, char *buf)
5027{
5028 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5029
5030 return sprintf(buf, "0x%016llx\n", rbd_dev->header.features);
5031}
5032
5033static ssize_t rbd_major_show(struct device *dev,
5034 struct device_attribute *attr, char *buf)
5035{
5036 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5037
5038 if (rbd_dev->major)
5039 return sprintf(buf, "%d\n", rbd_dev->major);
5040
5041 return sprintf(buf, "(none)\n");
5042}
5043
5044static ssize_t rbd_minor_show(struct device *dev,
5045 struct device_attribute *attr, char *buf)
5046{
5047 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5048
5049 return sprintf(buf, "%d\n", rbd_dev->minor);
5050}
5051
5052static ssize_t rbd_client_addr_show(struct device *dev,
5053 struct device_attribute *attr, char *buf)
5054{
5055 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5056 struct ceph_entity_addr *client_addr =
5057 ceph_client_addr(rbd_dev->rbd_client->client);
5058
5059 return sprintf(buf, "%pISpc/%u\n", &client_addr->in_addr,
5060 le32_to_cpu(client_addr->nonce));
5061}
5062
5063static ssize_t rbd_client_id_show(struct device *dev,
5064 struct device_attribute *attr, char *buf)
5065{
5066 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5067
5068 return sprintf(buf, "client%lld\n",
5069 ceph_client_gid(rbd_dev->rbd_client->client));
5070}
5071
5072static ssize_t rbd_cluster_fsid_show(struct device *dev,
5073 struct device_attribute *attr, char *buf)
5074{
5075 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5076
5077 return sprintf(buf, "%pU\n", &rbd_dev->rbd_client->client->fsid);
5078}
5079
5080static ssize_t rbd_config_info_show(struct device *dev,
5081 struct device_attribute *attr, char *buf)
5082{
5083 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5084
5085 if (!capable(CAP_SYS_ADMIN))
5086 return -EPERM;
5087
5088 return sprintf(buf, "%s\n", rbd_dev->config_info);
5089}
5090
5091static ssize_t rbd_pool_show(struct device *dev,
5092 struct device_attribute *attr, char *buf)
5093{
5094 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5095
5096 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
5097}
5098
5099static ssize_t rbd_pool_id_show(struct device *dev,
5100 struct device_attribute *attr, char *buf)
5101{
5102 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5103
5104 return sprintf(buf, "%llu\n",
5105 (unsigned long long) rbd_dev->spec->pool_id);
5106}
5107
5108static ssize_t rbd_pool_ns_show(struct device *dev,
5109 struct device_attribute *attr, char *buf)
5110{
5111 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5112
5113 return sprintf(buf, "%s\n", rbd_dev->spec->pool_ns ?: "");
5114}
5115
5116static ssize_t rbd_name_show(struct device *dev,
5117 struct device_attribute *attr, char *buf)
5118{
5119 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5120
5121 if (rbd_dev->spec->image_name)
5122 return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
5123
5124 return sprintf(buf, "(unknown)\n");
5125}
5126
5127static ssize_t rbd_image_id_show(struct device *dev,
5128 struct device_attribute *attr, char *buf)
5129{
5130 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5131
5132 return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
5133}
5134
5135/*
5136 * Shows the name of the currently-mapped snapshot (or
5137 * RBD_SNAP_HEAD_NAME for the base image).
5138 */
5139static ssize_t rbd_snap_show(struct device *dev,
5140 struct device_attribute *attr,
5141 char *buf)
5142{
5143 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5144
5145 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
5146}
5147
5148static ssize_t rbd_snap_id_show(struct device *dev,
5149 struct device_attribute *attr, char *buf)
5150{
5151 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5152
5153 return sprintf(buf, "%llu\n", rbd_dev->spec->snap_id);
5154}
5155
5156/*
5157 * For a v2 image, shows the chain of parent images, separated by empty
5158 * lines. For v1 images or if there is no parent, shows "(no parent
5159 * image)".
5160 */
5161static ssize_t rbd_parent_show(struct device *dev,
5162 struct device_attribute *attr,
5163 char *buf)
5164{
5165 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5166 ssize_t count = 0;
5167
5168 if (!rbd_dev->parent)
5169 return sprintf(buf, "(no parent image)\n");
5170
5171 for ( ; rbd_dev->parent; rbd_dev = rbd_dev->parent) {
5172 struct rbd_spec *spec = rbd_dev->parent_spec;
5173
5174 count += sprintf(&buf[count], "%s"
5175 "pool_id %llu\npool_name %s\n"
5176 "pool_ns %s\n"
5177 "image_id %s\nimage_name %s\n"
5178 "snap_id %llu\nsnap_name %s\n"
5179 "overlap %llu\n",
5180 !count ? "" : "\n", /* first? */
5181 spec->pool_id, spec->pool_name,
5182 spec->pool_ns ?: "",
5183 spec->image_id, spec->image_name ?: "(unknown)",
5184 spec->snap_id, spec->snap_name,
5185 rbd_dev->parent_overlap);
5186 }
5187
5188 return count;
5189}
5190
5191static ssize_t rbd_image_refresh(struct device *dev,
5192 struct device_attribute *attr,
5193 const char *buf,
5194 size_t size)
5195{
5196 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5197 int ret;
5198
5199 if (!capable(CAP_SYS_ADMIN))
5200 return -EPERM;
5201
5202 ret = rbd_dev_refresh(rbd_dev);
5203 if (ret)
5204 return ret;
5205
5206 return size;
5207}
5208
5209static DEVICE_ATTR(size, 0444, rbd_size_show, NULL);
5210static DEVICE_ATTR(features, 0444, rbd_features_show, NULL);
5211static DEVICE_ATTR(major, 0444, rbd_major_show, NULL);
5212static DEVICE_ATTR(minor, 0444, rbd_minor_show, NULL);
5213static DEVICE_ATTR(client_addr, 0444, rbd_client_addr_show, NULL);
5214static DEVICE_ATTR(client_id, 0444, rbd_client_id_show, NULL);
5215static DEVICE_ATTR(cluster_fsid, 0444, rbd_cluster_fsid_show, NULL);
5216static DEVICE_ATTR(config_info, 0400, rbd_config_info_show, NULL);
5217static DEVICE_ATTR(pool, 0444, rbd_pool_show, NULL);
5218static DEVICE_ATTR(pool_id, 0444, rbd_pool_id_show, NULL);
5219static DEVICE_ATTR(pool_ns, 0444, rbd_pool_ns_show, NULL);
5220static DEVICE_ATTR(name, 0444, rbd_name_show, NULL);
5221static DEVICE_ATTR(image_id, 0444, rbd_image_id_show, NULL);
5222static DEVICE_ATTR(refresh, 0200, NULL, rbd_image_refresh);
5223static DEVICE_ATTR(current_snap, 0444, rbd_snap_show, NULL);
5224static DEVICE_ATTR(snap_id, 0444, rbd_snap_id_show, NULL);
5225static DEVICE_ATTR(parent, 0444, rbd_parent_show, NULL);
5226
5227static struct attribute *rbd_attrs[] = {
5228 &dev_attr_size.attr,
5229 &dev_attr_features.attr,
5230 &dev_attr_major.attr,
5231 &dev_attr_minor.attr,
5232 &dev_attr_client_addr.attr,
5233 &dev_attr_client_id.attr,
5234 &dev_attr_cluster_fsid.attr,
5235 &dev_attr_config_info.attr,
5236 &dev_attr_pool.attr,
5237 &dev_attr_pool_id.attr,
5238 &dev_attr_pool_ns.attr,
5239 &dev_attr_name.attr,
5240 &dev_attr_image_id.attr,
5241 &dev_attr_current_snap.attr,
5242 &dev_attr_snap_id.attr,
5243 &dev_attr_parent.attr,
5244 &dev_attr_refresh.attr,
5245 NULL
5246};
5247
5248static struct attribute_group rbd_attr_group = {
5249 .attrs = rbd_attrs,
5250};
5251
5252static const struct attribute_group *rbd_attr_groups[] = {
5253 &rbd_attr_group,
5254 NULL
5255};
5256
5257static void rbd_dev_release(struct device *dev);
5258
5259static const struct device_type rbd_device_type = {
5260 .name = "rbd",
5261 .groups = rbd_attr_groups,
5262 .release = rbd_dev_release,
5263};
5264
5265static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
5266{
5267 kref_get(&spec->kref);
5268
5269 return spec;
5270}
5271
5272static void rbd_spec_free(struct kref *kref);
5273static void rbd_spec_put(struct rbd_spec *spec)
5274{
5275 if (spec)
5276 kref_put(&spec->kref, rbd_spec_free);
5277}
5278
5279static struct rbd_spec *rbd_spec_alloc(void)
5280{
5281 struct rbd_spec *spec;
5282
5283 spec = kzalloc(sizeof (*spec), GFP_KERNEL);
5284 if (!spec)
5285 return NULL;
5286
5287 spec->pool_id = CEPH_NOPOOL;
5288 spec->snap_id = CEPH_NOSNAP;
5289 kref_init(&spec->kref);
5290
5291 return spec;
5292}
5293
5294static void rbd_spec_free(struct kref *kref)
5295{
5296 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
5297
5298 kfree(spec->pool_name);
5299 kfree(spec->pool_ns);
5300 kfree(spec->image_id);
5301 kfree(spec->image_name);
5302 kfree(spec->snap_name);
5303 kfree(spec);
5304}
5305
5306static void rbd_dev_free(struct rbd_device *rbd_dev)
5307{
5308 WARN_ON(rbd_dev->watch_state != RBD_WATCH_STATE_UNREGISTERED);
5309 WARN_ON(rbd_dev->lock_state != RBD_LOCK_STATE_UNLOCKED);
5310
5311 ceph_oid_destroy(&rbd_dev->header_oid);
5312 ceph_oloc_destroy(&rbd_dev->header_oloc);
5313 kfree(rbd_dev->config_info);
5314
5315 rbd_put_client(rbd_dev->rbd_client);
5316 rbd_spec_put(rbd_dev->spec);
5317 kfree(rbd_dev->opts);
5318 kfree(rbd_dev);
5319}
5320
5321static void rbd_dev_release(struct device *dev)
5322{
5323 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5324 bool need_put = !!rbd_dev->opts;
5325
5326 if (need_put) {
5327 destroy_workqueue(rbd_dev->task_wq);
5328 ida_free(&rbd_dev_id_ida, rbd_dev->dev_id);
5329 }
5330
5331 rbd_dev_free(rbd_dev);
5332
5333 /*
5334 * This is racy, but way better than putting module outside of
5335 * the release callback. The race window is pretty small, so
5336 * doing something similar to dm (dm-builtin.c) is overkill.
5337 */
5338 if (need_put)
5339 module_put(THIS_MODULE);
5340}
5341
5342static struct rbd_device *__rbd_dev_create(struct rbd_spec *spec)
5343{
5344 struct rbd_device *rbd_dev;
5345
5346 rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL);
5347 if (!rbd_dev)
5348 return NULL;
5349
5350 spin_lock_init(&rbd_dev->lock);
5351 INIT_LIST_HEAD(&rbd_dev->node);
5352 init_rwsem(&rbd_dev->header_rwsem);
5353
5354 rbd_dev->header.data_pool_id = CEPH_NOPOOL;
5355 ceph_oid_init(&rbd_dev->header_oid);
5356 rbd_dev->header_oloc.pool = spec->pool_id;
5357 if (spec->pool_ns) {
5358 WARN_ON(!*spec->pool_ns);
5359 rbd_dev->header_oloc.pool_ns =
5360 ceph_find_or_create_string(spec->pool_ns,
5361 strlen(spec->pool_ns));
5362 }
5363
5364 mutex_init(&rbd_dev->watch_mutex);
5365 rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED;
5366 INIT_DELAYED_WORK(&rbd_dev->watch_dwork, rbd_reregister_watch);
5367
5368 init_rwsem(&rbd_dev->lock_rwsem);
5369 rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED;
5370 INIT_WORK(&rbd_dev->acquired_lock_work, rbd_notify_acquired_lock);
5371 INIT_WORK(&rbd_dev->released_lock_work, rbd_notify_released_lock);
5372 INIT_DELAYED_WORK(&rbd_dev->lock_dwork, rbd_acquire_lock);
5373 INIT_WORK(&rbd_dev->unlock_work, rbd_release_lock_work);
5374 spin_lock_init(&rbd_dev->lock_lists_lock);
5375 INIT_LIST_HEAD(&rbd_dev->acquiring_list);
5376 INIT_LIST_HEAD(&rbd_dev->running_list);
5377 init_completion(&rbd_dev->acquire_wait);
5378 init_completion(&rbd_dev->quiescing_wait);
5379
5380 spin_lock_init(&rbd_dev->object_map_lock);
5381
5382 rbd_dev->dev.bus = &rbd_bus_type;
5383 rbd_dev->dev.type = &rbd_device_type;
5384 rbd_dev->dev.parent = &rbd_root_dev;
5385 device_initialize(&rbd_dev->dev);
5386
5387 return rbd_dev;
5388}
5389
5390/*
5391 * Create a mapping rbd_dev.
5392 */
5393static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
5394 struct rbd_spec *spec,
5395 struct rbd_options *opts)
5396{
5397 struct rbd_device *rbd_dev;
5398
5399 rbd_dev = __rbd_dev_create(spec);
5400 if (!rbd_dev)
5401 return NULL;
5402
5403 /* get an id and fill in device name */
5404 rbd_dev->dev_id = ida_alloc_max(&rbd_dev_id_ida,
5405 minor_to_rbd_dev_id(1 << MINORBITS) - 1,
5406 GFP_KERNEL);
5407 if (rbd_dev->dev_id < 0)
5408 goto fail_rbd_dev;
5409
5410 sprintf(rbd_dev->name, RBD_DRV_NAME "%d", rbd_dev->dev_id);
5411 rbd_dev->task_wq = alloc_ordered_workqueue("%s-tasks", WQ_MEM_RECLAIM,
5412 rbd_dev->name);
5413 if (!rbd_dev->task_wq)
5414 goto fail_dev_id;
5415
5416 /* we have a ref from do_rbd_add() */
5417 __module_get(THIS_MODULE);
5418
5419 rbd_dev->rbd_client = rbdc;
5420 rbd_dev->spec = spec;
5421 rbd_dev->opts = opts;
5422
5423 dout("%s rbd_dev %p dev_id %d\n", __func__, rbd_dev, rbd_dev->dev_id);
5424 return rbd_dev;
5425
5426fail_dev_id:
5427 ida_free(&rbd_dev_id_ida, rbd_dev->dev_id);
5428fail_rbd_dev:
5429 rbd_dev_free(rbd_dev);
5430 return NULL;
5431}
5432
5433static void rbd_dev_destroy(struct rbd_device *rbd_dev)
5434{
5435 if (rbd_dev)
5436 put_device(&rbd_dev->dev);
5437}
5438
5439/*
5440 * Get the size and object order for an image snapshot, or if
5441 * snap_id is CEPH_NOSNAP, gets this information for the base
5442 * image.
5443 */
5444static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
5445 u8 *order, u64 *snap_size)
5446{
5447 __le64 snapid = cpu_to_le64(snap_id);
5448 int ret;
5449 struct {
5450 u8 order;
5451 __le64 size;
5452 } __attribute__ ((packed)) size_buf = { 0 };
5453
5454 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5455 &rbd_dev->header_oloc, "get_size",
5456 &snapid, sizeof(snapid),
5457 &size_buf, sizeof(size_buf));
5458 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5459 if (ret < 0)
5460 return ret;
5461 if (ret < sizeof (size_buf))
5462 return -ERANGE;
5463
5464 if (order) {
5465 *order = size_buf.order;
5466 dout(" order %u", (unsigned int)*order);
5467 }
5468 *snap_size = le64_to_cpu(size_buf.size);
5469
5470 dout(" snap_id 0x%016llx snap_size = %llu\n",
5471 (unsigned long long)snap_id,
5472 (unsigned long long)*snap_size);
5473
5474 return 0;
5475}
5476
5477static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev,
5478 char **pobject_prefix)
5479{
5480 size_t size;
5481 void *reply_buf;
5482 char *object_prefix;
5483 int ret;
5484 void *p;
5485
5486 /* Response will be an encoded string, which includes a length */
5487 size = sizeof(__le32) + RBD_OBJ_PREFIX_LEN_MAX;
5488 reply_buf = kzalloc(size, GFP_KERNEL);
5489 if (!reply_buf)
5490 return -ENOMEM;
5491
5492 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5493 &rbd_dev->header_oloc, "get_object_prefix",
5494 NULL, 0, reply_buf, size);
5495 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5496 if (ret < 0)
5497 goto out;
5498
5499 p = reply_buf;
5500 object_prefix = ceph_extract_encoded_string(&p, p + ret, NULL,
5501 GFP_NOIO);
5502 if (IS_ERR(object_prefix)) {
5503 ret = PTR_ERR(object_prefix);
5504 goto out;
5505 }
5506 ret = 0;
5507
5508 *pobject_prefix = object_prefix;
5509 dout(" object_prefix = %s\n", object_prefix);
5510out:
5511 kfree(reply_buf);
5512
5513 return ret;
5514}
5515
5516static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
5517 bool read_only, u64 *snap_features)
5518{
5519 struct {
5520 __le64 snap_id;
5521 u8 read_only;
5522 } features_in;
5523 struct {
5524 __le64 features;
5525 __le64 incompat;
5526 } __attribute__ ((packed)) features_buf = { 0 };
5527 u64 unsup;
5528 int ret;
5529
5530 features_in.snap_id = cpu_to_le64(snap_id);
5531 features_in.read_only = read_only;
5532
5533 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5534 &rbd_dev->header_oloc, "get_features",
5535 &features_in, sizeof(features_in),
5536 &features_buf, sizeof(features_buf));
5537 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5538 if (ret < 0)
5539 return ret;
5540 if (ret < sizeof (features_buf))
5541 return -ERANGE;
5542
5543 unsup = le64_to_cpu(features_buf.incompat) & ~RBD_FEATURES_SUPPORTED;
5544 if (unsup) {
5545 rbd_warn(rbd_dev, "image uses unsupported features: 0x%llx",
5546 unsup);
5547 return -ENXIO;
5548 }
5549
5550 *snap_features = le64_to_cpu(features_buf.features);
5551
5552 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
5553 (unsigned long long)snap_id,
5554 (unsigned long long)*snap_features,
5555 (unsigned long long)le64_to_cpu(features_buf.incompat));
5556
5557 return 0;
5558}
5559
5560/*
5561 * These are generic image flags, but since they are used only for
5562 * object map, store them in rbd_dev->object_map_flags.
5563 *
5564 * For the same reason, this function is called only on object map
5565 * (re)load and not on header refresh.
5566 */
5567static int rbd_dev_v2_get_flags(struct rbd_device *rbd_dev)
5568{
5569 __le64 snapid = cpu_to_le64(rbd_dev->spec->snap_id);
5570 __le64 flags;
5571 int ret;
5572
5573 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5574 &rbd_dev->header_oloc, "get_flags",
5575 &snapid, sizeof(snapid),
5576 &flags, sizeof(flags));
5577 if (ret < 0)
5578 return ret;
5579 if (ret < sizeof(flags))
5580 return -EBADMSG;
5581
5582 rbd_dev->object_map_flags = le64_to_cpu(flags);
5583 return 0;
5584}
5585
5586struct parent_image_info {
5587 u64 pool_id;
5588 const char *pool_ns;
5589 const char *image_id;
5590 u64 snap_id;
5591
5592 bool has_overlap;
5593 u64 overlap;
5594};
5595
5596static void rbd_parent_info_cleanup(struct parent_image_info *pii)
5597{
5598 kfree(pii->pool_ns);
5599 kfree(pii->image_id);
5600
5601 memset(pii, 0, sizeof(*pii));
5602}
5603
5604/*
5605 * The caller is responsible for @pii.
5606 */
5607static int decode_parent_image_spec(void **p, void *end,
5608 struct parent_image_info *pii)
5609{
5610 u8 struct_v;
5611 u32 struct_len;
5612 int ret;
5613
5614 ret = ceph_start_decoding(p, end, 1, "ParentImageSpec",
5615 &struct_v, &struct_len);
5616 if (ret)
5617 return ret;
5618
5619 ceph_decode_64_safe(p, end, pii->pool_id, e_inval);
5620 pii->pool_ns = ceph_extract_encoded_string(p, end, NULL, GFP_KERNEL);
5621 if (IS_ERR(pii->pool_ns)) {
5622 ret = PTR_ERR(pii->pool_ns);
5623 pii->pool_ns = NULL;
5624 return ret;
5625 }
5626 pii->image_id = ceph_extract_encoded_string(p, end, NULL, GFP_KERNEL);
5627 if (IS_ERR(pii->image_id)) {
5628 ret = PTR_ERR(pii->image_id);
5629 pii->image_id = NULL;
5630 return ret;
5631 }
5632 ceph_decode_64_safe(p, end, pii->snap_id, e_inval);
5633 return 0;
5634
5635e_inval:
5636 return -EINVAL;
5637}
5638
5639static int __get_parent_info(struct rbd_device *rbd_dev,
5640 struct page *req_page,
5641 struct page *reply_page,
5642 struct parent_image_info *pii)
5643{
5644 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
5645 size_t reply_len = PAGE_SIZE;
5646 void *p, *end;
5647 int ret;
5648
5649 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
5650 "rbd", "parent_get", CEPH_OSD_FLAG_READ,
5651 req_page, sizeof(u64), &reply_page, &reply_len);
5652 if (ret)
5653 return ret == -EOPNOTSUPP ? 1 : ret;
5654
5655 p = page_address(reply_page);
5656 end = p + reply_len;
5657 ret = decode_parent_image_spec(&p, end, pii);
5658 if (ret)
5659 return ret;
5660
5661 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
5662 "rbd", "parent_overlap_get", CEPH_OSD_FLAG_READ,
5663 req_page, sizeof(u64), &reply_page, &reply_len);
5664 if (ret)
5665 return ret;
5666
5667 p = page_address(reply_page);
5668 end = p + reply_len;
5669 ceph_decode_8_safe(&p, end, pii->has_overlap, e_inval);
5670 if (pii->has_overlap)
5671 ceph_decode_64_safe(&p, end, pii->overlap, e_inval);
5672
5673 dout("%s pool_id %llu pool_ns %s image_id %s snap_id %llu has_overlap %d overlap %llu\n",
5674 __func__, pii->pool_id, pii->pool_ns, pii->image_id, pii->snap_id,
5675 pii->has_overlap, pii->overlap);
5676 return 0;
5677
5678e_inval:
5679 return -EINVAL;
5680}
5681
5682/*
5683 * The caller is responsible for @pii.
5684 */
5685static int __get_parent_info_legacy(struct rbd_device *rbd_dev,
5686 struct page *req_page,
5687 struct page *reply_page,
5688 struct parent_image_info *pii)
5689{
5690 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
5691 size_t reply_len = PAGE_SIZE;
5692 void *p, *end;
5693 int ret;
5694
5695 ret = ceph_osdc_call(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
5696 "rbd", "get_parent", CEPH_OSD_FLAG_READ,
5697 req_page, sizeof(u64), &reply_page, &reply_len);
5698 if (ret)
5699 return ret;
5700
5701 p = page_address(reply_page);
5702 end = p + reply_len;
5703 ceph_decode_64_safe(&p, end, pii->pool_id, e_inval);
5704 pii->image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
5705 if (IS_ERR(pii->image_id)) {
5706 ret = PTR_ERR(pii->image_id);
5707 pii->image_id = NULL;
5708 return ret;
5709 }
5710 ceph_decode_64_safe(&p, end, pii->snap_id, e_inval);
5711 pii->has_overlap = true;
5712 ceph_decode_64_safe(&p, end, pii->overlap, e_inval);
5713
5714 dout("%s pool_id %llu pool_ns %s image_id %s snap_id %llu has_overlap %d overlap %llu\n",
5715 __func__, pii->pool_id, pii->pool_ns, pii->image_id, pii->snap_id,
5716 pii->has_overlap, pii->overlap);
5717 return 0;
5718
5719e_inval:
5720 return -EINVAL;
5721}
5722
5723static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev,
5724 struct parent_image_info *pii)
5725{
5726 struct page *req_page, *reply_page;
5727 void *p;
5728 int ret;
5729
5730 req_page = alloc_page(GFP_KERNEL);
5731 if (!req_page)
5732 return -ENOMEM;
5733
5734 reply_page = alloc_page(GFP_KERNEL);
5735 if (!reply_page) {
5736 __free_page(req_page);
5737 return -ENOMEM;
5738 }
5739
5740 p = page_address(req_page);
5741 ceph_encode_64(&p, rbd_dev->spec->snap_id);
5742 ret = __get_parent_info(rbd_dev, req_page, reply_page, pii);
5743 if (ret > 0)
5744 ret = __get_parent_info_legacy(rbd_dev, req_page, reply_page,
5745 pii);
5746
5747 __free_page(req_page);
5748 __free_page(reply_page);
5749 return ret;
5750}
5751
5752static int rbd_dev_setup_parent(struct rbd_device *rbd_dev)
5753{
5754 struct rbd_spec *parent_spec;
5755 struct parent_image_info pii = { 0 };
5756 int ret;
5757
5758 parent_spec = rbd_spec_alloc();
5759 if (!parent_spec)
5760 return -ENOMEM;
5761
5762 ret = rbd_dev_v2_parent_info(rbd_dev, &pii);
5763 if (ret)
5764 goto out_err;
5765
5766 if (pii.pool_id == CEPH_NOPOOL || !pii.has_overlap)
5767 goto out; /* No parent? No problem. */
5768
5769 /* The ceph file layout needs to fit pool id in 32 bits */
5770
5771 ret = -EIO;
5772 if (pii.pool_id > (u64)U32_MAX) {
5773 rbd_warn(NULL, "parent pool id too large (%llu > %u)",
5774 (unsigned long long)pii.pool_id, U32_MAX);
5775 goto out_err;
5776 }
5777
5778 /*
5779 * The parent won't change except when the clone is flattened,
5780 * so we only need to record the parent image spec once.
5781 */
5782 parent_spec->pool_id = pii.pool_id;
5783 if (pii.pool_ns && *pii.pool_ns) {
5784 parent_spec->pool_ns = pii.pool_ns;
5785 pii.pool_ns = NULL;
5786 }
5787 parent_spec->image_id = pii.image_id;
5788 pii.image_id = NULL;
5789 parent_spec->snap_id = pii.snap_id;
5790
5791 rbd_assert(!rbd_dev->parent_spec);
5792 rbd_dev->parent_spec = parent_spec;
5793 parent_spec = NULL; /* rbd_dev now owns this */
5794
5795 /*
5796 * Record the parent overlap. If it's zero, issue a warning as
5797 * we will proceed as if there is no parent.
5798 */
5799 if (!pii.overlap)
5800 rbd_warn(rbd_dev, "clone is standalone (overlap 0)");
5801 rbd_dev->parent_overlap = pii.overlap;
5802
5803out:
5804 ret = 0;
5805out_err:
5806 rbd_parent_info_cleanup(&pii);
5807 rbd_spec_put(parent_spec);
5808 return ret;
5809}
5810
5811static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev,
5812 u64 *stripe_unit, u64 *stripe_count)
5813{
5814 struct {
5815 __le64 stripe_unit;
5816 __le64 stripe_count;
5817 } __attribute__ ((packed)) striping_info_buf = { 0 };
5818 size_t size = sizeof (striping_info_buf);
5819 int ret;
5820
5821 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5822 &rbd_dev->header_oloc, "get_stripe_unit_count",
5823 NULL, 0, &striping_info_buf, size);
5824 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5825 if (ret < 0)
5826 return ret;
5827 if (ret < size)
5828 return -ERANGE;
5829
5830 *stripe_unit = le64_to_cpu(striping_info_buf.stripe_unit);
5831 *stripe_count = le64_to_cpu(striping_info_buf.stripe_count);
5832 dout(" stripe_unit = %llu stripe_count = %llu\n", *stripe_unit,
5833 *stripe_count);
5834
5835 return 0;
5836}
5837
5838static int rbd_dev_v2_data_pool(struct rbd_device *rbd_dev, s64 *data_pool_id)
5839{
5840 __le64 data_pool_buf;
5841 int ret;
5842
5843 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
5844 &rbd_dev->header_oloc, "get_data_pool",
5845 NULL, 0, &data_pool_buf,
5846 sizeof(data_pool_buf));
5847 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5848 if (ret < 0)
5849 return ret;
5850 if (ret < sizeof(data_pool_buf))
5851 return -EBADMSG;
5852
5853 *data_pool_id = le64_to_cpu(data_pool_buf);
5854 dout(" data_pool_id = %lld\n", *data_pool_id);
5855 WARN_ON(*data_pool_id == CEPH_NOPOOL);
5856
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 struct ceph_snap_context **psnapc)
6050{
6051 size_t size;
6052 int ret;
6053 void *reply_buf;
6054 void *p;
6055 void *end;
6056 u64 seq;
6057 u32 snap_count;
6058 struct ceph_snap_context *snapc;
6059 u32 i;
6060
6061 /*
6062 * We'll need room for the seq value (maximum snapshot id),
6063 * snapshot count, and array of that many snapshot ids.
6064 * For now we have a fixed upper limit on the number we're
6065 * prepared to receive.
6066 */
6067 size = sizeof (__le64) + sizeof (__le32) +
6068 RBD_MAX_SNAP_COUNT * sizeof (__le64);
6069 reply_buf = kzalloc(size, GFP_KERNEL);
6070 if (!reply_buf)
6071 return -ENOMEM;
6072
6073 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
6074 &rbd_dev->header_oloc, "get_snapcontext",
6075 NULL, 0, reply_buf, size);
6076 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
6077 if (ret < 0)
6078 goto out;
6079
6080 p = reply_buf;
6081 end = reply_buf + ret;
6082 ret = -ERANGE;
6083 ceph_decode_64_safe(&p, end, seq, out);
6084 ceph_decode_32_safe(&p, end, snap_count, out);
6085
6086 /*
6087 * Make sure the reported number of snapshot ids wouldn't go
6088 * beyond the end of our buffer. But before checking that,
6089 * make sure the computed size of the snapshot context we
6090 * allocate is representable in a size_t.
6091 */
6092 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
6093 / sizeof (u64)) {
6094 ret = -EINVAL;
6095 goto out;
6096 }
6097 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
6098 goto out;
6099 ret = 0;
6100
6101 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
6102 if (!snapc) {
6103 ret = -ENOMEM;
6104 goto out;
6105 }
6106 snapc->seq = seq;
6107 for (i = 0; i < snap_count; i++)
6108 snapc->snaps[i] = ceph_decode_64(&p);
6109
6110 *psnapc = snapc;
6111 dout(" snap context seq = %llu, snap_count = %u\n",
6112 (unsigned long long)seq, (unsigned int)snap_count);
6113out:
6114 kfree(reply_buf);
6115
6116 return ret;
6117}
6118
6119static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
6120 u64 snap_id)
6121{
6122 size_t size;
6123 void *reply_buf;
6124 __le64 snapid;
6125 int ret;
6126 void *p;
6127 void *end;
6128 char *snap_name;
6129
6130 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
6131 reply_buf = kmalloc(size, GFP_KERNEL);
6132 if (!reply_buf)
6133 return ERR_PTR(-ENOMEM);
6134
6135 snapid = cpu_to_le64(snap_id);
6136 ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
6137 &rbd_dev->header_oloc, "get_snapshot_name",
6138 &snapid, sizeof(snapid), reply_buf, size);
6139 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
6140 if (ret < 0) {
6141 snap_name = ERR_PTR(ret);
6142 goto out;
6143 }
6144
6145 p = reply_buf;
6146 end = reply_buf + ret;
6147 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
6148 if (IS_ERR(snap_name))
6149 goto out;
6150
6151 dout(" snap_id 0x%016llx snap_name = %s\n",
6152 (unsigned long long)snap_id, snap_name);
6153out:
6154 kfree(reply_buf);
6155
6156 return snap_name;
6157}
6158
6159static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev,
6160 struct rbd_image_header *header,
6161 bool first_time)
6162{
6163 int ret;
6164
6165 ret = _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
6166 first_time ? &header->obj_order : NULL,
6167 &header->image_size);
6168 if (ret)
6169 return ret;
6170
6171 if (first_time) {
6172 ret = rbd_dev_v2_header_onetime(rbd_dev, header);
6173 if (ret)
6174 return ret;
6175 }
6176
6177 ret = rbd_dev_v2_snap_context(rbd_dev, &header->snapc);
6178 if (ret)
6179 return ret;
6180
6181 return 0;
6182}
6183
6184static int rbd_dev_header_info(struct rbd_device *rbd_dev,
6185 struct rbd_image_header *header,
6186 bool first_time)
6187{
6188 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
6189 rbd_assert(!header->object_prefix && !header->snapc);
6190
6191 if (rbd_dev->image_format == 1)
6192 return rbd_dev_v1_header_info(rbd_dev, header, first_time);
6193
6194 return rbd_dev_v2_header_info(rbd_dev, header, first_time);
6195}
6196
6197/*
6198 * Skips over white space at *buf, and updates *buf to point to the
6199 * first found non-space character (if any). Returns the length of
6200 * the token (string of non-white space characters) found. Note
6201 * that *buf must be terminated with '\0'.
6202 */
6203static inline size_t next_token(const char **buf)
6204{
6205 /*
6206 * These are the characters that produce nonzero for
6207 * isspace() in the "C" and "POSIX" locales.
6208 */
6209 static const char spaces[] = " \f\n\r\t\v";
6210
6211 *buf += strspn(*buf, spaces); /* Find start of token */
6212
6213 return strcspn(*buf, spaces); /* Return token length */
6214}
6215
6216/*
6217 * Finds the next token in *buf, dynamically allocates a buffer big
6218 * enough to hold a copy of it, and copies the token into the new
6219 * buffer. The copy is guaranteed to be terminated with '\0'. Note
6220 * that a duplicate buffer is created even for a zero-length token.
6221 *
6222 * Returns a pointer to the newly-allocated duplicate, or a null
6223 * pointer if memory for the duplicate was not available. If
6224 * the lenp argument is a non-null pointer, the length of the token
6225 * (not including the '\0') is returned in *lenp.
6226 *
6227 * If successful, the *buf pointer will be updated to point beyond
6228 * the end of the found token.
6229 *
6230 * Note: uses GFP_KERNEL for allocation.
6231 */
6232static inline char *dup_token(const char **buf, size_t *lenp)
6233{
6234 char *dup;
6235 size_t len;
6236
6237 len = next_token(buf);
6238 dup = kmemdup(*buf, len + 1, GFP_KERNEL);
6239 if (!dup)
6240 return NULL;
6241 *(dup + len) = '\0';
6242 *buf += len;
6243
6244 if (lenp)
6245 *lenp = len;
6246
6247 return dup;
6248}
6249
6250static int rbd_parse_param(struct fs_parameter *param,
6251 struct rbd_parse_opts_ctx *pctx)
6252{
6253 struct rbd_options *opt = pctx->opts;
6254 struct fs_parse_result result;
6255 struct p_log log = {.prefix = "rbd"};
6256 int token, ret;
6257
6258 ret = ceph_parse_param(param, pctx->copts, NULL);
6259 if (ret != -ENOPARAM)
6260 return ret;
6261
6262 token = __fs_parse(&log, rbd_parameters, param, &result);
6263 dout("%s fs_parse '%s' token %d\n", __func__, param->key, token);
6264 if (token < 0) {
6265 if (token == -ENOPARAM)
6266 return inval_plog(&log, "Unknown parameter '%s'",
6267 param->key);
6268 return token;
6269 }
6270
6271 switch (token) {
6272 case Opt_queue_depth:
6273 if (result.uint_32 < 1)
6274 goto out_of_range;
6275 opt->queue_depth = result.uint_32;
6276 break;
6277 case Opt_alloc_size:
6278 if (result.uint_32 < SECTOR_SIZE)
6279 goto out_of_range;
6280 if (!is_power_of_2(result.uint_32))
6281 return inval_plog(&log, "alloc_size must be a power of 2");
6282 opt->alloc_size = result.uint_32;
6283 break;
6284 case Opt_lock_timeout:
6285 /* 0 is "wait forever" (i.e. infinite timeout) */
6286 if (result.uint_32 > INT_MAX / 1000)
6287 goto out_of_range;
6288 opt->lock_timeout = msecs_to_jiffies(result.uint_32 * 1000);
6289 break;
6290 case Opt_pool_ns:
6291 kfree(pctx->spec->pool_ns);
6292 pctx->spec->pool_ns = param->string;
6293 param->string = NULL;
6294 break;
6295 case Opt_compression_hint:
6296 switch (result.uint_32) {
6297 case Opt_compression_hint_none:
6298 opt->alloc_hint_flags &=
6299 ~(CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE |
6300 CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE);
6301 break;
6302 case Opt_compression_hint_compressible:
6303 opt->alloc_hint_flags |=
6304 CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE;
6305 opt->alloc_hint_flags &=
6306 ~CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE;
6307 break;
6308 case Opt_compression_hint_incompressible:
6309 opt->alloc_hint_flags |=
6310 CEPH_OSD_ALLOC_HINT_FLAG_INCOMPRESSIBLE;
6311 opt->alloc_hint_flags &=
6312 ~CEPH_OSD_ALLOC_HINT_FLAG_COMPRESSIBLE;
6313 break;
6314 default:
6315 BUG();
6316 }
6317 break;
6318 case Opt_read_only:
6319 opt->read_only = true;
6320 break;
6321 case Opt_read_write:
6322 opt->read_only = false;
6323 break;
6324 case Opt_lock_on_read:
6325 opt->lock_on_read = true;
6326 break;
6327 case Opt_exclusive:
6328 opt->exclusive = true;
6329 break;
6330 case Opt_notrim:
6331 opt->trim = false;
6332 break;
6333 default:
6334 BUG();
6335 }
6336
6337 return 0;
6338
6339out_of_range:
6340 return inval_plog(&log, "%s out of range", param->key);
6341}
6342
6343/*
6344 * This duplicates most of generic_parse_monolithic(), untying it from
6345 * fs_context and skipping standard superblock and security options.
6346 */
6347static int rbd_parse_options(char *options, struct rbd_parse_opts_ctx *pctx)
6348{
6349 char *key;
6350 int ret = 0;
6351
6352 dout("%s '%s'\n", __func__, options);
6353 while ((key = strsep(&options, ",")) != NULL) {
6354 if (*key) {
6355 struct fs_parameter param = {
6356 .key = key,
6357 .type = fs_value_is_flag,
6358 };
6359 char *value = strchr(key, '=');
6360 size_t v_len = 0;
6361
6362 if (value) {
6363 if (value == key)
6364 continue;
6365 *value++ = 0;
6366 v_len = strlen(value);
6367 param.string = kmemdup_nul(value, v_len,
6368 GFP_KERNEL);
6369 if (!param.string)
6370 return -ENOMEM;
6371 param.type = fs_value_is_string;
6372 }
6373 param.size = v_len;
6374
6375 ret = rbd_parse_param(&param, pctx);
6376 kfree(param.string);
6377 if (ret)
6378 break;
6379 }
6380 }
6381
6382 return ret;
6383}
6384
6385/*
6386 * Parse the options provided for an "rbd add" (i.e., rbd image
6387 * mapping) request. These arrive via a write to /sys/bus/rbd/add,
6388 * and the data written is passed here via a NUL-terminated buffer.
6389 * Returns 0 if successful or an error code otherwise.
6390 *
6391 * The information extracted from these options is recorded in
6392 * the other parameters which return dynamically-allocated
6393 * structures:
6394 * ceph_opts
6395 * The address of a pointer that will refer to a ceph options
6396 * structure. Caller must release the returned pointer using
6397 * ceph_destroy_options() when it is no longer needed.
6398 * rbd_opts
6399 * Address of an rbd options pointer. Fully initialized by
6400 * this function; caller must release with kfree().
6401 * spec
6402 * Address of an rbd image specification pointer. Fully
6403 * initialized by this function based on parsed options.
6404 * Caller must release with rbd_spec_put().
6405 *
6406 * The options passed take this form:
6407 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
6408 * where:
6409 * <mon_addrs>
6410 * A comma-separated list of one or more monitor addresses.
6411 * A monitor address is an ip address, optionally followed
6412 * by a port number (separated by a colon).
6413 * I.e.: ip1[:port1][,ip2[:port2]...]
6414 * <options>
6415 * A comma-separated list of ceph and/or rbd options.
6416 * <pool_name>
6417 * The name of the rados pool containing the rbd image.
6418 * <image_name>
6419 * The name of the image in that pool to map.
6420 * <snap_id>
6421 * An optional snapshot id. If provided, the mapping will
6422 * present data from the image at the time that snapshot was
6423 * created. The image head is used if no snapshot id is
6424 * provided. Snapshot mappings are always read-only.
6425 */
6426static int rbd_add_parse_args(const char *buf,
6427 struct ceph_options **ceph_opts,
6428 struct rbd_options **opts,
6429 struct rbd_spec **rbd_spec)
6430{
6431 size_t len;
6432 char *options;
6433 const char *mon_addrs;
6434 char *snap_name;
6435 size_t mon_addrs_size;
6436 struct rbd_parse_opts_ctx pctx = { 0 };
6437 int ret;
6438
6439 /* The first four tokens are required */
6440
6441 len = next_token(&buf);
6442 if (!len) {
6443 rbd_warn(NULL, "no monitor address(es) provided");
6444 return -EINVAL;
6445 }
6446 mon_addrs = buf;
6447 mon_addrs_size = len;
6448 buf += len;
6449
6450 ret = -EINVAL;
6451 options = dup_token(&buf, NULL);
6452 if (!options)
6453 return -ENOMEM;
6454 if (!*options) {
6455 rbd_warn(NULL, "no options provided");
6456 goto out_err;
6457 }
6458
6459 pctx.spec = rbd_spec_alloc();
6460 if (!pctx.spec)
6461 goto out_mem;
6462
6463 pctx.spec->pool_name = dup_token(&buf, NULL);
6464 if (!pctx.spec->pool_name)
6465 goto out_mem;
6466 if (!*pctx.spec->pool_name) {
6467 rbd_warn(NULL, "no pool name provided");
6468 goto out_err;
6469 }
6470
6471 pctx.spec->image_name = dup_token(&buf, NULL);
6472 if (!pctx.spec->image_name)
6473 goto out_mem;
6474 if (!*pctx.spec->image_name) {
6475 rbd_warn(NULL, "no image name provided");
6476 goto out_err;
6477 }
6478
6479 /*
6480 * Snapshot name is optional; default is to use "-"
6481 * (indicating the head/no snapshot).
6482 */
6483 len = next_token(&buf);
6484 if (!len) {
6485 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
6486 len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
6487 } else if (len > RBD_MAX_SNAP_NAME_LEN) {
6488 ret = -ENAMETOOLONG;
6489 goto out_err;
6490 }
6491 snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
6492 if (!snap_name)
6493 goto out_mem;
6494 *(snap_name + len) = '\0';
6495 pctx.spec->snap_name = snap_name;
6496
6497 pctx.copts = ceph_alloc_options();
6498 if (!pctx.copts)
6499 goto out_mem;
6500
6501 /* Initialize all rbd options to the defaults */
6502
6503 pctx.opts = kzalloc(sizeof(*pctx.opts), GFP_KERNEL);
6504 if (!pctx.opts)
6505 goto out_mem;
6506
6507 pctx.opts->read_only = RBD_READ_ONLY_DEFAULT;
6508 pctx.opts->queue_depth = RBD_QUEUE_DEPTH_DEFAULT;
6509 pctx.opts->alloc_size = RBD_ALLOC_SIZE_DEFAULT;
6510 pctx.opts->lock_timeout = RBD_LOCK_TIMEOUT_DEFAULT;
6511 pctx.opts->lock_on_read = RBD_LOCK_ON_READ_DEFAULT;
6512 pctx.opts->exclusive = RBD_EXCLUSIVE_DEFAULT;
6513 pctx.opts->trim = RBD_TRIM_DEFAULT;
6514
6515 ret = ceph_parse_mon_ips(mon_addrs, mon_addrs_size, pctx.copts, NULL,
6516 ',');
6517 if (ret)
6518 goto out_err;
6519
6520 ret = rbd_parse_options(options, &pctx);
6521 if (ret)
6522 goto out_err;
6523
6524 *ceph_opts = pctx.copts;
6525 *opts = pctx.opts;
6526 *rbd_spec = pctx.spec;
6527 kfree(options);
6528 return 0;
6529
6530out_mem:
6531 ret = -ENOMEM;
6532out_err:
6533 kfree(pctx.opts);
6534 ceph_destroy_options(pctx.copts);
6535 rbd_spec_put(pctx.spec);
6536 kfree(options);
6537 return ret;
6538}
6539
6540static void rbd_dev_image_unlock(struct rbd_device *rbd_dev)
6541{
6542 down_write(&rbd_dev->lock_rwsem);
6543 if (__rbd_is_lock_owner(rbd_dev))
6544 __rbd_release_lock(rbd_dev);
6545 up_write(&rbd_dev->lock_rwsem);
6546}
6547
6548/*
6549 * If the wait is interrupted, an error is returned even if the lock
6550 * was successfully acquired. rbd_dev_image_unlock() will release it
6551 * if needed.
6552 */
6553static int rbd_add_acquire_lock(struct rbd_device *rbd_dev)
6554{
6555 long ret;
6556
6557 if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK)) {
6558 if (!rbd_dev->opts->exclusive && !rbd_dev->opts->lock_on_read)
6559 return 0;
6560
6561 rbd_warn(rbd_dev, "exclusive-lock feature is not enabled");
6562 return -EINVAL;
6563 }
6564
6565 if (rbd_is_ro(rbd_dev))
6566 return 0;
6567
6568 rbd_assert(!rbd_is_lock_owner(rbd_dev));
6569 queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
6570 ret = wait_for_completion_killable_timeout(&rbd_dev->acquire_wait,
6571 ceph_timeout_jiffies(rbd_dev->opts->lock_timeout));
6572 if (ret > 0) {
6573 ret = rbd_dev->acquire_err;
6574 } else {
6575 cancel_delayed_work_sync(&rbd_dev->lock_dwork);
6576 if (!ret)
6577 ret = -ETIMEDOUT;
6578
6579 rbd_warn(rbd_dev, "failed to acquire lock: %ld", ret);
6580 }
6581 if (ret)
6582 return ret;
6583
6584 return 0;
6585}
6586
6587/*
6588 * An rbd format 2 image has a unique identifier, distinct from the
6589 * name given to it by the user. Internally, that identifier is
6590 * what's used to specify the names of objects related to the image.
6591 *
6592 * A special "rbd id" object is used to map an rbd image name to its
6593 * id. If that object doesn't exist, then there is no v2 rbd image
6594 * with the supplied name.
6595 *
6596 * This function will record the given rbd_dev's image_id field if
6597 * it can be determined, and in that case will return 0. If any
6598 * errors occur a negative errno will be returned and the rbd_dev's
6599 * image_id field will be unchanged (and should be NULL).
6600 */
6601static int rbd_dev_image_id(struct rbd_device *rbd_dev)
6602{
6603 int ret;
6604 size_t size;
6605 CEPH_DEFINE_OID_ONSTACK(oid);
6606 void *response;
6607 char *image_id;
6608
6609 /*
6610 * When probing a parent image, the image id is already
6611 * known (and the image name likely is not). There's no
6612 * need to fetch the image id again in this case. We
6613 * do still need to set the image format though.
6614 */
6615 if (rbd_dev->spec->image_id) {
6616 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;
6617
6618 return 0;
6619 }
6620
6621 /*
6622 * First, see if the format 2 image id file exists, and if
6623 * so, get the image's persistent id from it.
6624 */
6625 ret = ceph_oid_aprintf(&oid, GFP_KERNEL, "%s%s", RBD_ID_PREFIX,
6626 rbd_dev->spec->image_name);
6627 if (ret)
6628 return ret;
6629
6630 dout("rbd id object name is %s\n", oid.name);
6631
6632 /* Response will be an encoded string, which includes a length */
6633 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
6634 response = kzalloc(size, GFP_NOIO);
6635 if (!response) {
6636 ret = -ENOMEM;
6637 goto out;
6638 }
6639
6640 /* If it doesn't exist we'll assume it's a format 1 image */
6641
6642 ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc,
6643 "get_id", NULL, 0,
6644 response, size);
6645 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
6646 if (ret == -ENOENT) {
6647 image_id = kstrdup("", GFP_KERNEL);
6648 ret = image_id ? 0 : -ENOMEM;
6649 if (!ret)
6650 rbd_dev->image_format = 1;
6651 } else if (ret >= 0) {
6652 void *p = response;
6653
6654 image_id = ceph_extract_encoded_string(&p, p + ret,
6655 NULL, GFP_NOIO);
6656 ret = PTR_ERR_OR_ZERO(image_id);
6657 if (!ret)
6658 rbd_dev->image_format = 2;
6659 }
6660
6661 if (!ret) {
6662 rbd_dev->spec->image_id = image_id;
6663 dout("image_id is %s\n", image_id);
6664 }
6665out:
6666 kfree(response);
6667 ceph_oid_destroy(&oid);
6668 return ret;
6669}
6670
6671/*
6672 * Undo whatever state changes are made by v1 or v2 header info
6673 * call.
6674 */
6675static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
6676{
6677 rbd_dev_parent_put(rbd_dev);
6678 rbd_object_map_free(rbd_dev);
6679 rbd_dev_mapping_clear(rbd_dev);
6680
6681 /* Free dynamic fields from the header, then zero it out */
6682
6683 rbd_image_header_cleanup(&rbd_dev->header);
6684}
6685
6686static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev,
6687 struct rbd_image_header *header)
6688{
6689 int ret;
6690
6691 ret = rbd_dev_v2_object_prefix(rbd_dev, &header->object_prefix);
6692 if (ret)
6693 return ret;
6694
6695 /*
6696 * Get the and check features for the image. Currently the
6697 * features are assumed to never change.
6698 */
6699 ret = _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
6700 rbd_is_ro(rbd_dev), &header->features);
6701 if (ret)
6702 return ret;
6703
6704 /* If the image supports fancy striping, get its parameters */
6705
6706 if (header->features & RBD_FEATURE_STRIPINGV2) {
6707 ret = rbd_dev_v2_striping_info(rbd_dev, &header->stripe_unit,
6708 &header->stripe_count);
6709 if (ret)
6710 return ret;
6711 }
6712
6713 if (header->features & RBD_FEATURE_DATA_POOL) {
6714 ret = rbd_dev_v2_data_pool(rbd_dev, &header->data_pool_id);
6715 if (ret)
6716 return ret;
6717 }
6718
6719 return 0;
6720}
6721
6722/*
6723 * @depth is rbd_dev_image_probe() -> rbd_dev_probe_parent() ->
6724 * rbd_dev_image_probe() recursion depth, which means it's also the
6725 * length of the already discovered part of the parent chain.
6726 */
6727static int rbd_dev_probe_parent(struct rbd_device *rbd_dev, int depth)
6728{
6729 struct rbd_device *parent = NULL;
6730 int ret;
6731
6732 if (!rbd_dev->parent_spec)
6733 return 0;
6734
6735 if (++depth > RBD_MAX_PARENT_CHAIN_LEN) {
6736 pr_info("parent chain is too long (%d)\n", depth);
6737 ret = -EINVAL;
6738 goto out_err;
6739 }
6740
6741 parent = __rbd_dev_create(rbd_dev->parent_spec);
6742 if (!parent) {
6743 ret = -ENOMEM;
6744 goto out_err;
6745 }
6746
6747 /*
6748 * Images related by parent/child relationships always share
6749 * rbd_client and spec/parent_spec, so bump their refcounts.
6750 */
6751 parent->rbd_client = __rbd_get_client(rbd_dev->rbd_client);
6752 parent->spec = rbd_spec_get(rbd_dev->parent_spec);
6753
6754 __set_bit(RBD_DEV_FLAG_READONLY, &parent->flags);
6755
6756 ret = rbd_dev_image_probe(parent, depth);
6757 if (ret < 0)
6758 goto out_err;
6759
6760 rbd_dev->parent = parent;
6761 atomic_set(&rbd_dev->parent_ref, 1);
6762 return 0;
6763
6764out_err:
6765 rbd_dev_unparent(rbd_dev);
6766 rbd_dev_destroy(parent);
6767 return ret;
6768}
6769
6770static void rbd_dev_device_release(struct rbd_device *rbd_dev)
6771{
6772 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
6773 rbd_free_disk(rbd_dev);
6774 if (!single_major)
6775 unregister_blkdev(rbd_dev->major, rbd_dev->name);
6776}
6777
6778/*
6779 * rbd_dev->header_rwsem must be locked for write and will be unlocked
6780 * upon return.
6781 */
6782static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
6783{
6784 int ret;
6785
6786 /* Record our major and minor device numbers. */
6787
6788 if (!single_major) {
6789 ret = register_blkdev(0, rbd_dev->name);
6790 if (ret < 0)
6791 goto err_out_unlock;
6792
6793 rbd_dev->major = ret;
6794 rbd_dev->minor = 0;
6795 } else {
6796 rbd_dev->major = rbd_major;
6797 rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id);
6798 }
6799
6800 /* Set up the blkdev mapping. */
6801
6802 ret = rbd_init_disk(rbd_dev);
6803 if (ret)
6804 goto err_out_blkdev;
6805
6806 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
6807 set_disk_ro(rbd_dev->disk, rbd_is_ro(rbd_dev));
6808
6809 ret = dev_set_name(&rbd_dev->dev, "%d", rbd_dev->dev_id);
6810 if (ret)
6811 goto err_out_disk;
6812
6813 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
6814 up_write(&rbd_dev->header_rwsem);
6815 return 0;
6816
6817err_out_disk:
6818 rbd_free_disk(rbd_dev);
6819err_out_blkdev:
6820 if (!single_major)
6821 unregister_blkdev(rbd_dev->major, rbd_dev->name);
6822err_out_unlock:
6823 up_write(&rbd_dev->header_rwsem);
6824 return ret;
6825}
6826
6827static int rbd_dev_header_name(struct rbd_device *rbd_dev)
6828{
6829 struct rbd_spec *spec = rbd_dev->spec;
6830 int ret;
6831
6832 /* Record the header object name for this rbd image. */
6833
6834 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
6835 if (rbd_dev->image_format == 1)
6836 ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s",
6837 spec->image_name, RBD_SUFFIX);
6838 else
6839 ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s",
6840 RBD_HEADER_PREFIX, spec->image_id);
6841
6842 return ret;
6843}
6844
6845static void rbd_print_dne(struct rbd_device *rbd_dev, bool is_snap)
6846{
6847 if (!is_snap) {
6848 pr_info("image %s/%s%s%s does not exist\n",
6849 rbd_dev->spec->pool_name,
6850 rbd_dev->spec->pool_ns ?: "",
6851 rbd_dev->spec->pool_ns ? "/" : "",
6852 rbd_dev->spec->image_name);
6853 } else {
6854 pr_info("snap %s/%s%s%s@%s does not exist\n",
6855 rbd_dev->spec->pool_name,
6856 rbd_dev->spec->pool_ns ?: "",
6857 rbd_dev->spec->pool_ns ? "/" : "",
6858 rbd_dev->spec->image_name,
6859 rbd_dev->spec->snap_name);
6860 }
6861}
6862
6863static void rbd_dev_image_release(struct rbd_device *rbd_dev)
6864{
6865 if (!rbd_is_ro(rbd_dev))
6866 rbd_unregister_watch(rbd_dev);
6867
6868 rbd_dev_unprobe(rbd_dev);
6869 rbd_dev->image_format = 0;
6870 kfree(rbd_dev->spec->image_id);
6871 rbd_dev->spec->image_id = NULL;
6872}
6873
6874/*
6875 * Probe for the existence of the header object for the given rbd
6876 * device. If this image is the one being mapped (i.e., not a
6877 * parent), initiate a watch on its header object before using that
6878 * object to get detailed information about the rbd image.
6879 *
6880 * On success, returns with header_rwsem held for write if called
6881 * with @depth == 0.
6882 */
6883static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth)
6884{
6885 bool need_watch = !rbd_is_ro(rbd_dev);
6886 int ret;
6887
6888 /*
6889 * Get the id from the image id object. Unless there's an
6890 * error, rbd_dev->spec->image_id will be filled in with
6891 * a dynamically-allocated string, and rbd_dev->image_format
6892 * will be set to either 1 or 2.
6893 */
6894 ret = rbd_dev_image_id(rbd_dev);
6895 if (ret)
6896 return ret;
6897
6898 ret = rbd_dev_header_name(rbd_dev);
6899 if (ret)
6900 goto err_out_format;
6901
6902 if (need_watch) {
6903 ret = rbd_register_watch(rbd_dev);
6904 if (ret) {
6905 if (ret == -ENOENT)
6906 rbd_print_dne(rbd_dev, false);
6907 goto err_out_format;
6908 }
6909 }
6910
6911 if (!depth)
6912 down_write(&rbd_dev->header_rwsem);
6913
6914 ret = rbd_dev_header_info(rbd_dev, &rbd_dev->header, true);
6915 if (ret) {
6916 if (ret == -ENOENT && !need_watch)
6917 rbd_print_dne(rbd_dev, false);
6918 goto err_out_probe;
6919 }
6920
6921 rbd_init_layout(rbd_dev);
6922
6923 /*
6924 * If this image is the one being mapped, we have pool name and
6925 * id, image name and id, and snap name - need to fill snap id.
6926 * Otherwise this is a parent image, identified by pool, image
6927 * and snap ids - need to fill in names for those ids.
6928 */
6929 if (!depth)
6930 ret = rbd_spec_fill_snap_id(rbd_dev);
6931 else
6932 ret = rbd_spec_fill_names(rbd_dev);
6933 if (ret) {
6934 if (ret == -ENOENT)
6935 rbd_print_dne(rbd_dev, true);
6936 goto err_out_probe;
6937 }
6938
6939 ret = rbd_dev_mapping_set(rbd_dev);
6940 if (ret)
6941 goto err_out_probe;
6942
6943 if (rbd_is_snap(rbd_dev) &&
6944 (rbd_dev->header.features & RBD_FEATURE_OBJECT_MAP)) {
6945 ret = rbd_object_map_load(rbd_dev);
6946 if (ret)
6947 goto err_out_probe;
6948 }
6949
6950 if (rbd_dev->header.features & RBD_FEATURE_LAYERING) {
6951 ret = rbd_dev_setup_parent(rbd_dev);
6952 if (ret)
6953 goto err_out_probe;
6954 }
6955
6956 ret = rbd_dev_probe_parent(rbd_dev, depth);
6957 if (ret)
6958 goto err_out_probe;
6959
6960 dout("discovered format %u image, header name is %s\n",
6961 rbd_dev->image_format, rbd_dev->header_oid.name);
6962 return 0;
6963
6964err_out_probe:
6965 if (!depth)
6966 up_write(&rbd_dev->header_rwsem);
6967 if (need_watch)
6968 rbd_unregister_watch(rbd_dev);
6969 rbd_dev_unprobe(rbd_dev);
6970err_out_format:
6971 rbd_dev->image_format = 0;
6972 kfree(rbd_dev->spec->image_id);
6973 rbd_dev->spec->image_id = NULL;
6974 return ret;
6975}
6976
6977static void rbd_dev_update_header(struct rbd_device *rbd_dev,
6978 struct rbd_image_header *header)
6979{
6980 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
6981 rbd_assert(rbd_dev->header.object_prefix); /* !first_time */
6982
6983 if (rbd_dev->header.image_size != header->image_size) {
6984 rbd_dev->header.image_size = header->image_size;
6985
6986 if (!rbd_is_snap(rbd_dev)) {
6987 rbd_dev->mapping.size = header->image_size;
6988 rbd_dev_update_size(rbd_dev);
6989 }
6990 }
6991
6992 ceph_put_snap_context(rbd_dev->header.snapc);
6993 rbd_dev->header.snapc = header->snapc;
6994 header->snapc = NULL;
6995
6996 if (rbd_dev->image_format == 1) {
6997 kfree(rbd_dev->header.snap_names);
6998 rbd_dev->header.snap_names = header->snap_names;
6999 header->snap_names = NULL;
7000
7001 kfree(rbd_dev->header.snap_sizes);
7002 rbd_dev->header.snap_sizes = header->snap_sizes;
7003 header->snap_sizes = NULL;
7004 }
7005}
7006
7007static void rbd_dev_update_parent(struct rbd_device *rbd_dev,
7008 struct parent_image_info *pii)
7009{
7010 if (pii->pool_id == CEPH_NOPOOL || !pii->has_overlap) {
7011 /*
7012 * Either the parent never existed, or we have
7013 * record of it but the image got flattened so it no
7014 * longer has a parent. When the parent of a
7015 * layered image disappears we immediately set the
7016 * overlap to 0. The effect of this is that all new
7017 * requests will be treated as if the image had no
7018 * parent.
7019 *
7020 * If !pii.has_overlap, the parent image spec is not
7021 * applicable. It's there to avoid duplication in each
7022 * snapshot record.
7023 */
7024 if (rbd_dev->parent_overlap) {
7025 rbd_dev->parent_overlap = 0;
7026 rbd_dev_parent_put(rbd_dev);
7027 pr_info("%s: clone has been flattened\n",
7028 rbd_dev->disk->disk_name);
7029 }
7030 } else {
7031 rbd_assert(rbd_dev->parent_spec);
7032
7033 /*
7034 * Update the parent overlap. If it became zero, issue
7035 * a warning as we will proceed as if there is no parent.
7036 */
7037 if (!pii->overlap && rbd_dev->parent_overlap)
7038 rbd_warn(rbd_dev,
7039 "clone has become standalone (overlap 0)");
7040 rbd_dev->parent_overlap = pii->overlap;
7041 }
7042}
7043
7044static int rbd_dev_refresh(struct rbd_device *rbd_dev)
7045{
7046 struct rbd_image_header header = { 0 };
7047 struct parent_image_info pii = { 0 };
7048 int ret;
7049
7050 dout("%s rbd_dev %p\n", __func__, rbd_dev);
7051
7052 ret = rbd_dev_header_info(rbd_dev, &header, false);
7053 if (ret)
7054 goto out;
7055
7056 /*
7057 * If there is a parent, see if it has disappeared due to the
7058 * mapped image getting flattened.
7059 */
7060 if (rbd_dev->parent) {
7061 ret = rbd_dev_v2_parent_info(rbd_dev, &pii);
7062 if (ret)
7063 goto out;
7064 }
7065
7066 down_write(&rbd_dev->header_rwsem);
7067 rbd_dev_update_header(rbd_dev, &header);
7068 if (rbd_dev->parent)
7069 rbd_dev_update_parent(rbd_dev, &pii);
7070 up_write(&rbd_dev->header_rwsem);
7071
7072out:
7073 rbd_parent_info_cleanup(&pii);
7074 rbd_image_header_cleanup(&header);
7075 return ret;
7076}
7077
7078static ssize_t do_rbd_add(const char *buf, size_t count)
7079{
7080 struct rbd_device *rbd_dev = NULL;
7081 struct ceph_options *ceph_opts = NULL;
7082 struct rbd_options *rbd_opts = NULL;
7083 struct rbd_spec *spec = NULL;
7084 struct rbd_client *rbdc;
7085 int rc;
7086
7087 if (!capable(CAP_SYS_ADMIN))
7088 return -EPERM;
7089
7090 if (!try_module_get(THIS_MODULE))
7091 return -ENODEV;
7092
7093 /* parse add command */
7094 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
7095 if (rc < 0)
7096 goto out;
7097
7098 rbdc = rbd_get_client(ceph_opts);
7099 if (IS_ERR(rbdc)) {
7100 rc = PTR_ERR(rbdc);
7101 goto err_out_args;
7102 }
7103
7104 /* pick the pool */
7105 rc = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, spec->pool_name);
7106 if (rc < 0) {
7107 if (rc == -ENOENT)
7108 pr_info("pool %s does not exist\n", spec->pool_name);
7109 goto err_out_client;
7110 }
7111 spec->pool_id = (u64)rc;
7112
7113 rbd_dev = rbd_dev_create(rbdc, spec, rbd_opts);
7114 if (!rbd_dev) {
7115 rc = -ENOMEM;
7116 goto err_out_client;
7117 }
7118 rbdc = NULL; /* rbd_dev now owns this */
7119 spec = NULL; /* rbd_dev now owns this */
7120 rbd_opts = NULL; /* rbd_dev now owns this */
7121
7122 /* if we are mapping a snapshot it will be a read-only mapping */
7123 if (rbd_dev->opts->read_only ||
7124 strcmp(rbd_dev->spec->snap_name, RBD_SNAP_HEAD_NAME))
7125 __set_bit(RBD_DEV_FLAG_READONLY, &rbd_dev->flags);
7126
7127 rbd_dev->config_info = kstrdup(buf, GFP_KERNEL);
7128 if (!rbd_dev->config_info) {
7129 rc = -ENOMEM;
7130 goto err_out_rbd_dev;
7131 }
7132
7133 rc = rbd_dev_image_probe(rbd_dev, 0);
7134 if (rc < 0)
7135 goto err_out_rbd_dev;
7136
7137 if (rbd_dev->opts->alloc_size > rbd_dev->layout.object_size) {
7138 rbd_warn(rbd_dev, "alloc_size adjusted to %u",
7139 rbd_dev->layout.object_size);
7140 rbd_dev->opts->alloc_size = rbd_dev->layout.object_size;
7141 }
7142
7143 rc = rbd_dev_device_setup(rbd_dev);
7144 if (rc)
7145 goto err_out_image_probe;
7146
7147 rc = rbd_add_acquire_lock(rbd_dev);
7148 if (rc)
7149 goto err_out_image_lock;
7150
7151 /* Everything's ready. Announce the disk to the world. */
7152
7153 rc = device_add(&rbd_dev->dev);
7154 if (rc)
7155 goto err_out_image_lock;
7156
7157 rc = device_add_disk(&rbd_dev->dev, rbd_dev->disk, NULL);
7158 if (rc)
7159 goto err_out_cleanup_disk;
7160
7161 spin_lock(&rbd_dev_list_lock);
7162 list_add_tail(&rbd_dev->node, &rbd_dev_list);
7163 spin_unlock(&rbd_dev_list_lock);
7164
7165 pr_info("%s: capacity %llu features 0x%llx\n", rbd_dev->disk->disk_name,
7166 (unsigned long long)get_capacity(rbd_dev->disk) << SECTOR_SHIFT,
7167 rbd_dev->header.features);
7168 rc = count;
7169out:
7170 module_put(THIS_MODULE);
7171 return rc;
7172
7173err_out_cleanup_disk:
7174 rbd_free_disk(rbd_dev);
7175err_out_image_lock:
7176 rbd_dev_image_unlock(rbd_dev);
7177 rbd_dev_device_release(rbd_dev);
7178err_out_image_probe:
7179 rbd_dev_image_release(rbd_dev);
7180err_out_rbd_dev:
7181 rbd_dev_destroy(rbd_dev);
7182err_out_client:
7183 rbd_put_client(rbdc);
7184err_out_args:
7185 rbd_spec_put(spec);
7186 kfree(rbd_opts);
7187 goto out;
7188}
7189
7190static ssize_t add_store(const struct bus_type *bus, const char *buf, size_t count)
7191{
7192 if (single_major)
7193 return -EINVAL;
7194
7195 return do_rbd_add(buf, count);
7196}
7197
7198static ssize_t add_single_major_store(const struct bus_type *bus, const char *buf,
7199 size_t count)
7200{
7201 return do_rbd_add(buf, count);
7202}
7203
7204static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
7205{
7206 while (rbd_dev->parent) {
7207 struct rbd_device *first = rbd_dev;
7208 struct rbd_device *second = first->parent;
7209 struct rbd_device *third;
7210
7211 /*
7212 * Follow to the parent with no grandparent and
7213 * remove it.
7214 */
7215 while (second && (third = second->parent)) {
7216 first = second;
7217 second = third;
7218 }
7219 rbd_assert(second);
7220 rbd_dev_image_release(second);
7221 rbd_dev_destroy(second);
7222 first->parent = NULL;
7223 first->parent_overlap = 0;
7224
7225 rbd_assert(first->parent_spec);
7226 rbd_spec_put(first->parent_spec);
7227 first->parent_spec = NULL;
7228 }
7229}
7230
7231static ssize_t do_rbd_remove(const char *buf, size_t count)
7232{
7233 struct rbd_device *rbd_dev = NULL;
7234 int dev_id;
7235 char opt_buf[6];
7236 bool force = false;
7237 int ret;
7238
7239 if (!capable(CAP_SYS_ADMIN))
7240 return -EPERM;
7241
7242 dev_id = -1;
7243 opt_buf[0] = '\0';
7244 sscanf(buf, "%d %5s", &dev_id, opt_buf);
7245 if (dev_id < 0) {
7246 pr_err("dev_id out of range\n");
7247 return -EINVAL;
7248 }
7249 if (opt_buf[0] != '\0') {
7250 if (!strcmp(opt_buf, "force")) {
7251 force = true;
7252 } else {
7253 pr_err("bad remove option at '%s'\n", opt_buf);
7254 return -EINVAL;
7255 }
7256 }
7257
7258 ret = -ENOENT;
7259 spin_lock(&rbd_dev_list_lock);
7260 list_for_each_entry(rbd_dev, &rbd_dev_list, node) {
7261 if (rbd_dev->dev_id == dev_id) {
7262 ret = 0;
7263 break;
7264 }
7265 }
7266 if (!ret) {
7267 spin_lock_irq(&rbd_dev->lock);
7268 if (rbd_dev->open_count && !force)
7269 ret = -EBUSY;
7270 else if (test_and_set_bit(RBD_DEV_FLAG_REMOVING,
7271 &rbd_dev->flags))
7272 ret = -EINPROGRESS;
7273 spin_unlock_irq(&rbd_dev->lock);
7274 }
7275 spin_unlock(&rbd_dev_list_lock);
7276 if (ret)
7277 return ret;
7278
7279 if (force) {
7280 /*
7281 * Prevent new IO from being queued and wait for existing
7282 * IO to complete/fail.
7283 */
7284 unsigned int memflags = blk_mq_freeze_queue(rbd_dev->disk->queue);
7285
7286 blk_mark_disk_dead(rbd_dev->disk);
7287 blk_mq_unfreeze_queue(rbd_dev->disk->queue, memflags);
7288 }
7289
7290 del_gendisk(rbd_dev->disk);
7291 spin_lock(&rbd_dev_list_lock);
7292 list_del_init(&rbd_dev->node);
7293 spin_unlock(&rbd_dev_list_lock);
7294 device_del(&rbd_dev->dev);
7295
7296 rbd_dev_image_unlock(rbd_dev);
7297 rbd_dev_device_release(rbd_dev);
7298 rbd_dev_image_release(rbd_dev);
7299 rbd_dev_destroy(rbd_dev);
7300 return count;
7301}
7302
7303static ssize_t remove_store(const struct bus_type *bus, const char *buf, size_t count)
7304{
7305 if (single_major)
7306 return -EINVAL;
7307
7308 return do_rbd_remove(buf, count);
7309}
7310
7311static ssize_t remove_single_major_store(const struct bus_type *bus, const char *buf,
7312 size_t count)
7313{
7314 return do_rbd_remove(buf, count);
7315}
7316
7317/*
7318 * create control files in sysfs
7319 * /sys/bus/rbd/...
7320 */
7321static int __init rbd_sysfs_init(void)
7322{
7323 int ret;
7324
7325 ret = device_register(&rbd_root_dev);
7326 if (ret < 0) {
7327 put_device(&rbd_root_dev);
7328 return ret;
7329 }
7330
7331 ret = bus_register(&rbd_bus_type);
7332 if (ret < 0)
7333 device_unregister(&rbd_root_dev);
7334
7335 return ret;
7336}
7337
7338static void __exit rbd_sysfs_cleanup(void)
7339{
7340 bus_unregister(&rbd_bus_type);
7341 device_unregister(&rbd_root_dev);
7342}
7343
7344static int __init rbd_slab_init(void)
7345{
7346 rbd_assert(!rbd_img_request_cache);
7347 rbd_img_request_cache = KMEM_CACHE(rbd_img_request, 0);
7348 if (!rbd_img_request_cache)
7349 return -ENOMEM;
7350
7351 rbd_assert(!rbd_obj_request_cache);
7352 rbd_obj_request_cache = KMEM_CACHE(rbd_obj_request, 0);
7353 if (!rbd_obj_request_cache)
7354 goto out_err;
7355
7356 return 0;
7357
7358out_err:
7359 kmem_cache_destroy(rbd_img_request_cache);
7360 rbd_img_request_cache = NULL;
7361 return -ENOMEM;
7362}
7363
7364static void rbd_slab_exit(void)
7365{
7366 rbd_assert(rbd_obj_request_cache);
7367 kmem_cache_destroy(rbd_obj_request_cache);
7368 rbd_obj_request_cache = NULL;
7369
7370 rbd_assert(rbd_img_request_cache);
7371 kmem_cache_destroy(rbd_img_request_cache);
7372 rbd_img_request_cache = NULL;
7373}
7374
7375static int __init rbd_init(void)
7376{
7377 int rc;
7378
7379 if (!libceph_compatible(NULL)) {
7380 rbd_warn(NULL, "libceph incompatibility (quitting)");
7381 return -EINVAL;
7382 }
7383
7384 rc = rbd_slab_init();
7385 if (rc)
7386 return rc;
7387
7388 /*
7389 * The number of active work items is limited by the number of
7390 * rbd devices * queue depth, so leave @max_active at default.
7391 */
7392 rbd_wq = alloc_workqueue(RBD_DRV_NAME, WQ_MEM_RECLAIM, 0);
7393 if (!rbd_wq) {
7394 rc = -ENOMEM;
7395 goto err_out_slab;
7396 }
7397
7398 if (single_major) {
7399 rbd_major = register_blkdev(0, RBD_DRV_NAME);
7400 if (rbd_major < 0) {
7401 rc = rbd_major;
7402 goto err_out_wq;
7403 }
7404 }
7405
7406 rc = rbd_sysfs_init();
7407 if (rc)
7408 goto err_out_blkdev;
7409
7410 if (single_major)
7411 pr_info("loaded (major %d)\n", rbd_major);
7412 else
7413 pr_info("loaded\n");
7414
7415 return 0;
7416
7417err_out_blkdev:
7418 if (single_major)
7419 unregister_blkdev(rbd_major, RBD_DRV_NAME);
7420err_out_wq:
7421 destroy_workqueue(rbd_wq);
7422err_out_slab:
7423 rbd_slab_exit();
7424 return rc;
7425}
7426
7427static void __exit rbd_exit(void)
7428{
7429 ida_destroy(&rbd_dev_id_ida);
7430 rbd_sysfs_cleanup();
7431 if (single_major)
7432 unregister_blkdev(rbd_major, RBD_DRV_NAME);
7433 destroy_workqueue(rbd_wq);
7434 rbd_slab_exit();
7435}
7436
7437module_init(rbd_init);
7438module_exit(rbd_exit);
7439
7440MODULE_AUTHOR("Alex Elder <elder@inktank.com>");
7441MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
7442MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
7443/* following authorship retained from original osdblk.c */
7444MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
7445
7446MODULE_DESCRIPTION("RADOS Block Device (RBD) driver");
7447MODULE_LICENSE("GPL");
Linux 6.x block layer and io_uring tree(s)