3 rbd.c -- Export ceph rados objects as a Linux block device
6 based on drivers/block/osdblk.c:
8 Copyright 2009 Red Hat, Inc.
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.
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.
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.
25 For usage instructions, please refer to:
27 Documentation/ABI/testing/sysfs-bus-rbd
31 #include <linux/ceph/libceph.h>
32 #include <linux/ceph/osd_client.h>
33 #include <linux/ceph/mon_client.h>
34 #include <linux/ceph/decode.h>
35 #include <linux/parser.h>
36 #include <linux/bsearch.h>
38 #include <linux/kernel.h>
39 #include <linux/device.h>
40 #include <linux/module.h>
42 #include <linux/blkdev.h>
43 #include <linux/slab.h>
45 #include "rbd_types.h"
47 #define RBD_DEBUG /* Activate rbd_assert() calls */
50 * The basic unit of block I/O is a sector. It is interpreted in a
51 * number of contexts in Linux (blk, bio, genhd), but the default is
52 * universally 512 bytes. These symbols are just slightly more
53 * meaningful than the bare numbers they represent.
55 #define SECTOR_SHIFT 9
56 #define SECTOR_SIZE (1ULL << SECTOR_SHIFT)
59 * Increment the given counter and return its updated value.
60 * If the counter is already 0 it will not be incremented.
61 * If the counter is already at its maximum value returns
62 * -EINVAL without updating it.
64 static int atomic_inc_return_safe(atomic_t *v)
68 counter = (unsigned int)__atomic_add_unless(v, 1, 0);
69 if (counter <= (unsigned int)INT_MAX)
77 /* Decrement the counter. Return the resulting value, or -EINVAL */
78 static int atomic_dec_return_safe(atomic_t *v)
82 counter = atomic_dec_return(v);
91 #define RBD_DRV_NAME "rbd"
92 #define RBD_DRV_NAME_LONG "rbd (rados block device)"
94 #define RBD_MINORS_PER_MAJOR 256 /* max minors per blkdev */
96 #define RBD_SNAP_DEV_NAME_PREFIX "snap_"
97 #define RBD_MAX_SNAP_NAME_LEN \
98 (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1))
100 #define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */
102 #define RBD_SNAP_HEAD_NAME "-"
104 #define BAD_SNAP_INDEX U32_MAX /* invalid index into snap array */
106 /* This allows a single page to hold an image name sent by OSD */
107 #define RBD_IMAGE_NAME_LEN_MAX (PAGE_SIZE - sizeof (__le32) - 1)
108 #define RBD_IMAGE_ID_LEN_MAX 64
110 #define RBD_OBJ_PREFIX_LEN_MAX 64
114 #define RBD_FEATURE_LAYERING (1<<0)
115 #define RBD_FEATURE_STRIPINGV2 (1<<1)
116 #define RBD_FEATURES_ALL \
117 (RBD_FEATURE_LAYERING | RBD_FEATURE_STRIPINGV2)
119 /* Features supported by this (client software) implementation. */
121 #define RBD_FEATURES_SUPPORTED (RBD_FEATURES_ALL)
124 * An RBD device name will be "rbd#", where the "rbd" comes from
125 * RBD_DRV_NAME above, and # is a unique integer identifier.
126 * MAX_INT_FORMAT_WIDTH is used in ensuring DEV_NAME_LEN is big
127 * enough to hold all possible device names.
129 #define DEV_NAME_LEN 32
130 #define MAX_INT_FORMAT_WIDTH ((5 * sizeof (int)) / 2 + 1)
133 * block device image metadata (in-memory version)
135 struct rbd_image_header {
136 /* These six fields never change for a given rbd image */
143 u64 features; /* Might be changeable someday? */
145 /* The remaining fields need to be updated occasionally */
147 struct ceph_snap_context *snapc;
148 char *snap_names; /* format 1 only */
149 u64 *snap_sizes; /* format 1 only */
153 * An rbd image specification.
155 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely
156 * identify an image. Each rbd_dev structure includes a pointer to
157 * an rbd_spec structure that encapsulates this identity.
159 * Each of the id's in an rbd_spec has an associated name. For a
160 * user-mapped image, the names are supplied and the id's associated
161 * with them are looked up. For a layered image, a parent image is
162 * defined by the tuple, and the names are looked up.
164 * An rbd_dev structure contains a parent_spec pointer which is
165 * non-null if the image it represents is a child in a layered
166 * image. This pointer will refer to the rbd_spec structure used
167 * by the parent rbd_dev for its own identity (i.e., the structure
168 * is shared between the parent and child).
170 * Since these structures are populated once, during the discovery
171 * phase of image construction, they are effectively immutable so
172 * we make no effort to synchronize access to them.
174 * Note that code herein does not assume the image name is known (it
175 * could be a null pointer).
179 const char *pool_name;
181 const char *image_id;
182 const char *image_name;
185 const char *snap_name;
191 * an instance of the client. multiple devices may share an rbd client.
194 struct ceph_client *client;
196 struct list_head node;
199 struct rbd_img_request;
200 typedef void (*rbd_img_callback_t)(struct rbd_img_request *);
202 #define BAD_WHICH U32_MAX /* Good which or bad which, which? */
204 struct rbd_obj_request;
205 typedef void (*rbd_obj_callback_t)(struct rbd_obj_request *);
207 enum obj_request_type {
208 OBJ_REQUEST_NODATA, OBJ_REQUEST_BIO, OBJ_REQUEST_PAGES
212 OBJ_REQ_DONE, /* completion flag: not done = 0, done = 1 */
213 OBJ_REQ_IMG_DATA, /* object usage: standalone = 0, image = 1 */
214 OBJ_REQ_KNOWN, /* EXISTS flag valid: no = 0, yes = 1 */
215 OBJ_REQ_EXISTS, /* target exists: no = 0, yes = 1 */
218 struct rbd_obj_request {
219 const char *object_name;
220 u64 offset; /* object start byte */
221 u64 length; /* bytes from offset */
225 * An object request associated with an image will have its
226 * img_data flag set; a standalone object request will not.
228 * A standalone object request will have which == BAD_WHICH
229 * and a null obj_request pointer.
231 * An object request initiated in support of a layered image
232 * object (to check for its existence before a write) will
233 * have which == BAD_WHICH and a non-null obj_request pointer.
235 * Finally, an object request for rbd image data will have
236 * which != BAD_WHICH, and will have a non-null img_request
237 * pointer. The value of which will be in the range
238 * 0..(img_request->obj_request_count-1).
241 struct rbd_obj_request *obj_request; /* STAT op */
243 struct rbd_img_request *img_request;
245 /* links for img_request->obj_requests list */
246 struct list_head links;
249 u32 which; /* posn image request list */
251 enum obj_request_type type;
253 struct bio *bio_list;
259 struct page **copyup_pages;
260 u32 copyup_page_count;
262 struct ceph_osd_request *osd_req;
264 u64 xferred; /* bytes transferred */
267 rbd_obj_callback_t callback;
268 struct completion completion;
274 IMG_REQ_WRITE, /* I/O direction: read = 0, write = 1 */
275 IMG_REQ_CHILD, /* initiator: block = 0, child image = 1 */
276 IMG_REQ_LAYERED, /* ENOENT handling: normal = 0, layered = 1 */
279 struct rbd_img_request {
280 struct rbd_device *rbd_dev;
281 u64 offset; /* starting image byte offset */
282 u64 length; /* byte count from offset */
285 u64 snap_id; /* for reads */
286 struct ceph_snap_context *snapc; /* for writes */
289 struct request *rq; /* block request */
290 struct rbd_obj_request *obj_request; /* obj req initiator */
292 struct page **copyup_pages;
293 u32 copyup_page_count;
294 spinlock_t completion_lock;/* protects next_completion */
296 rbd_img_callback_t callback;
297 u64 xferred;/* aggregate bytes transferred */
298 int result; /* first nonzero obj_request result */
300 u32 obj_request_count;
301 struct list_head obj_requests; /* rbd_obj_request structs */
306 #define for_each_obj_request(ireq, oreq) \
307 list_for_each_entry(oreq, &(ireq)->obj_requests, links)
308 #define for_each_obj_request_from(ireq, oreq) \
309 list_for_each_entry_from(oreq, &(ireq)->obj_requests, links)
310 #define for_each_obj_request_safe(ireq, oreq, n) \
311 list_for_each_entry_safe_reverse(oreq, n, &(ireq)->obj_requests, links)
323 int dev_id; /* blkdev unique id */
325 int major; /* blkdev assigned major */
326 struct gendisk *disk; /* blkdev's gendisk and rq */
328 u32 image_format; /* Either 1 or 2 */
329 struct rbd_client *rbd_client;
331 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */
333 spinlock_t lock; /* queue, flags, open_count */
335 struct rbd_image_header header;
336 unsigned long flags; /* possibly lock protected */
337 struct rbd_spec *spec;
341 struct ceph_file_layout layout;
343 struct ceph_osd_event *watch_event;
344 struct rbd_obj_request *watch_request;
346 struct rbd_spec *parent_spec;
349 struct rbd_device *parent;
351 /* protects updating the header */
352 struct rw_semaphore header_rwsem;
354 struct rbd_mapping mapping;
356 struct list_head node;
360 unsigned long open_count; /* protected by lock */
364 * Flag bits for rbd_dev->flags. If atomicity is required,
365 * rbd_dev->lock is used to protect access.
367 * Currently, only the "removing" flag (which is coupled with the
368 * "open_count" field) requires atomic access.
371 RBD_DEV_FLAG_EXISTS, /* mapped snapshot has not been deleted */
372 RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */
375 static DEFINE_MUTEX(ctl_mutex); /* Serialize open/close/setup/teardown */
377 static LIST_HEAD(rbd_dev_list); /* devices */
378 static DEFINE_SPINLOCK(rbd_dev_list_lock);
380 static LIST_HEAD(rbd_client_list); /* clients */
381 static DEFINE_SPINLOCK(rbd_client_list_lock);
383 /* Slab caches for frequently-allocated structures */
385 static struct kmem_cache *rbd_img_request_cache;
386 static struct kmem_cache *rbd_obj_request_cache;
387 static struct kmem_cache *rbd_segment_name_cache;
389 static int rbd_img_request_submit(struct rbd_img_request *img_request);
391 static void rbd_dev_device_release(struct device *dev);
393 static ssize_t rbd_add(struct bus_type *bus, const char *buf,
395 static ssize_t rbd_remove(struct bus_type *bus, const char *buf,
397 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping);
398 static void rbd_spec_put(struct rbd_spec *spec);
400 static struct bus_attribute rbd_bus_attrs[] = {
401 __ATTR(add, S_IWUSR, NULL, rbd_add),
402 __ATTR(remove, S_IWUSR, NULL, rbd_remove),
406 static struct bus_type rbd_bus_type = {
408 .bus_attrs = rbd_bus_attrs,
411 static void rbd_root_dev_release(struct device *dev)
415 static struct device rbd_root_dev = {
417 .release = rbd_root_dev_release,
420 static __printf(2, 3)
421 void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...)
423 struct va_format vaf;
431 printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf);
432 else if (rbd_dev->disk)
433 printk(KERN_WARNING "%s: %s: %pV\n",
434 RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf);
435 else if (rbd_dev->spec && rbd_dev->spec->image_name)
436 printk(KERN_WARNING "%s: image %s: %pV\n",
437 RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf);
438 else if (rbd_dev->spec && rbd_dev->spec->image_id)
439 printk(KERN_WARNING "%s: id %s: %pV\n",
440 RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf);
442 printk(KERN_WARNING "%s: rbd_dev %p: %pV\n",
443 RBD_DRV_NAME, rbd_dev, &vaf);
448 #define rbd_assert(expr) \
449 if (unlikely(!(expr))) { \
450 printk(KERN_ERR "\nAssertion failure in %s() " \
452 "\trbd_assert(%s);\n\n", \
453 __func__, __LINE__, #expr); \
456 #else /* !RBD_DEBUG */
457 # define rbd_assert(expr) ((void) 0)
458 #endif /* !RBD_DEBUG */
460 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request);
461 static void rbd_img_parent_read(struct rbd_obj_request *obj_request);
462 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev);
464 static int rbd_dev_refresh(struct rbd_device *rbd_dev);
465 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev);
466 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev);
467 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
469 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
470 u8 *order, u64 *snap_size);
471 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
473 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name);
475 static int rbd_open(struct block_device *bdev, fmode_t mode)
477 struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
478 bool removing = false;
480 if ((mode & FMODE_WRITE) && rbd_dev->mapping.read_only)
483 spin_lock_irq(&rbd_dev->lock);
484 if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags))
487 rbd_dev->open_count++;
488 spin_unlock_irq(&rbd_dev->lock);
492 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
493 (void) get_device(&rbd_dev->dev);
494 set_device_ro(bdev, rbd_dev->mapping.read_only);
495 mutex_unlock(&ctl_mutex);
500 static int rbd_release(struct gendisk *disk, fmode_t mode)
502 struct rbd_device *rbd_dev = disk->private_data;
503 unsigned long open_count_before;
505 spin_lock_irq(&rbd_dev->lock);
506 open_count_before = rbd_dev->open_count--;
507 spin_unlock_irq(&rbd_dev->lock);
508 rbd_assert(open_count_before > 0);
510 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
511 put_device(&rbd_dev->dev);
512 mutex_unlock(&ctl_mutex);
517 static const struct block_device_operations rbd_bd_ops = {
518 .owner = THIS_MODULE,
520 .release = rbd_release,
524 * Initialize an rbd client instance. Success or not, this function
525 * consumes ceph_opts.
527 static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
529 struct rbd_client *rbdc;
532 dout("%s:\n", __func__);
533 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
537 kref_init(&rbdc->kref);
538 INIT_LIST_HEAD(&rbdc->node);
540 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
542 rbdc->client = ceph_create_client(ceph_opts, rbdc, 0, 0);
543 if (IS_ERR(rbdc->client))
545 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
547 ret = ceph_open_session(rbdc->client);
551 spin_lock(&rbd_client_list_lock);
552 list_add_tail(&rbdc->node, &rbd_client_list);
553 spin_unlock(&rbd_client_list_lock);
555 mutex_unlock(&ctl_mutex);
556 dout("%s: rbdc %p\n", __func__, rbdc);
561 ceph_destroy_client(rbdc->client);
563 mutex_unlock(&ctl_mutex);
567 ceph_destroy_options(ceph_opts);
568 dout("%s: error %d\n", __func__, ret);
573 static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
575 kref_get(&rbdc->kref);
581 * Find a ceph client with specific addr and configuration. If
582 * found, bump its reference count.
584 static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
586 struct rbd_client *client_node;
589 if (ceph_opts->flags & CEPH_OPT_NOSHARE)
592 spin_lock(&rbd_client_list_lock);
593 list_for_each_entry(client_node, &rbd_client_list, node) {
594 if (!ceph_compare_options(ceph_opts, client_node->client)) {
595 __rbd_get_client(client_node);
601 spin_unlock(&rbd_client_list_lock);
603 return found ? client_node : NULL;
613 /* string args above */
616 /* Boolean args above */
620 static match_table_t rbd_opts_tokens = {
622 /* string args above */
623 {Opt_read_only, "read_only"},
624 {Opt_read_only, "ro"}, /* Alternate spelling */
625 {Opt_read_write, "read_write"},
626 {Opt_read_write, "rw"}, /* Alternate spelling */
627 /* Boolean args above */
635 #define RBD_READ_ONLY_DEFAULT false
637 static int parse_rbd_opts_token(char *c, void *private)
639 struct rbd_options *rbd_opts = private;
640 substring_t argstr[MAX_OPT_ARGS];
641 int token, intval, ret;
643 token = match_token(c, rbd_opts_tokens, argstr);
647 if (token < Opt_last_int) {
648 ret = match_int(&argstr[0], &intval);
650 pr_err("bad mount option arg (not int) "
654 dout("got int token %d val %d\n", token, intval);
655 } else if (token > Opt_last_int && token < Opt_last_string) {
656 dout("got string token %d val %s\n", token,
658 } else if (token > Opt_last_string && token < Opt_last_bool) {
659 dout("got Boolean token %d\n", token);
661 dout("got token %d\n", token);
666 rbd_opts->read_only = true;
669 rbd_opts->read_only = false;
679 * Get a ceph client with specific addr and configuration, if one does
680 * not exist create it. Either way, ceph_opts is consumed by this
683 static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
685 struct rbd_client *rbdc;
687 rbdc = rbd_client_find(ceph_opts);
688 if (rbdc) /* using an existing client */
689 ceph_destroy_options(ceph_opts);
691 rbdc = rbd_client_create(ceph_opts);
697 * Destroy ceph client
699 * Caller must hold rbd_client_list_lock.
701 static void rbd_client_release(struct kref *kref)
703 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
705 dout("%s: rbdc %p\n", __func__, rbdc);
706 spin_lock(&rbd_client_list_lock);
707 list_del(&rbdc->node);
708 spin_unlock(&rbd_client_list_lock);
710 ceph_destroy_client(rbdc->client);
715 * Drop reference to ceph client node. If it's not referenced anymore, release
718 static void rbd_put_client(struct rbd_client *rbdc)
721 kref_put(&rbdc->kref, rbd_client_release);
724 static bool rbd_image_format_valid(u32 image_format)
726 return image_format == 1 || image_format == 2;
729 static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
734 /* The header has to start with the magic rbd header text */
735 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
738 /* The bio layer requires at least sector-sized I/O */
740 if (ondisk->options.order < SECTOR_SHIFT)
743 /* If we use u64 in a few spots we may be able to loosen this */
745 if (ondisk->options.order > 8 * sizeof (int) - 1)
749 * The size of a snapshot header has to fit in a size_t, and
750 * that limits the number of snapshots.
752 snap_count = le32_to_cpu(ondisk->snap_count);
753 size = SIZE_MAX - sizeof (struct ceph_snap_context);
754 if (snap_count > size / sizeof (__le64))
758 * Not only that, but the size of the entire the snapshot
759 * header must also be representable in a size_t.
761 size -= snap_count * sizeof (__le64);
762 if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
769 * Fill an rbd image header with information from the given format 1
772 static int rbd_header_from_disk(struct rbd_device *rbd_dev,
773 struct rbd_image_header_ondisk *ondisk)
775 struct rbd_image_header *header = &rbd_dev->header;
776 bool first_time = header->object_prefix == NULL;
777 struct ceph_snap_context *snapc;
778 char *object_prefix = NULL;
779 char *snap_names = NULL;
780 u64 *snap_sizes = NULL;
786 /* Allocate this now to avoid having to handle failure below */
791 len = strnlen(ondisk->object_prefix,
792 sizeof (ondisk->object_prefix));
793 object_prefix = kmalloc(len + 1, GFP_KERNEL);
796 memcpy(object_prefix, ondisk->object_prefix, len);
797 object_prefix[len] = '\0';
800 /* Allocate the snapshot context and fill it in */
802 snap_count = le32_to_cpu(ondisk->snap_count);
803 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
806 snapc->seq = le64_to_cpu(ondisk->snap_seq);
808 struct rbd_image_snap_ondisk *snaps;
809 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);
811 /* We'll keep a copy of the snapshot names... */
813 if (snap_names_len > (u64)SIZE_MAX)
815 snap_names = kmalloc(snap_names_len, GFP_KERNEL);
819 /* ...as well as the array of their sizes. */
821 size = snap_count * sizeof (*header->snap_sizes);
822 snap_sizes = kmalloc(size, GFP_KERNEL);
827 * Copy the names, and fill in each snapshot's id
830 * Note that rbd_dev_v1_header_info() guarantees the
831 * ondisk buffer we're working with has
832 * snap_names_len bytes beyond the end of the
833 * snapshot id array, this memcpy() is safe.
835 memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len);
836 snaps = ondisk->snaps;
837 for (i = 0; i < snap_count; i++) {
838 snapc->snaps[i] = le64_to_cpu(snaps[i].id);
839 snap_sizes[i] = le64_to_cpu(snaps[i].image_size);
843 /* We won't fail any more, fill in the header */
845 down_write(&rbd_dev->header_rwsem);
847 header->object_prefix = object_prefix;
848 header->obj_order = ondisk->options.order;
849 header->crypt_type = ondisk->options.crypt_type;
850 header->comp_type = ondisk->options.comp_type;
851 /* The rest aren't used for format 1 images */
852 header->stripe_unit = 0;
853 header->stripe_count = 0;
854 header->features = 0;
856 ceph_put_snap_context(header->snapc);
857 kfree(header->snap_names);
858 kfree(header->snap_sizes);
861 /* The remaining fields always get updated (when we refresh) */
863 header->image_size = le64_to_cpu(ondisk->image_size);
864 header->snapc = snapc;
865 header->snap_names = snap_names;
866 header->snap_sizes = snap_sizes;
868 /* Make sure mapping size is consistent with header info */
870 if (rbd_dev->spec->snap_id == CEPH_NOSNAP || first_time)
871 if (rbd_dev->mapping.size != header->image_size)
872 rbd_dev->mapping.size = header->image_size;
874 up_write(&rbd_dev->header_rwsem);
882 ceph_put_snap_context(snapc);
883 kfree(object_prefix);
888 static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
890 const char *snap_name;
892 rbd_assert(which < rbd_dev->header.snapc->num_snaps);
894 /* Skip over names until we find the one we are looking for */
896 snap_name = rbd_dev->header.snap_names;
898 snap_name += strlen(snap_name) + 1;
900 return kstrdup(snap_name, GFP_KERNEL);
904 * Snapshot id comparison function for use with qsort()/bsearch().
905 * Note that result is for snapshots in *descending* order.
907 static int snapid_compare_reverse(const void *s1, const void *s2)
909 u64 snap_id1 = *(u64 *)s1;
910 u64 snap_id2 = *(u64 *)s2;
912 if (snap_id1 < snap_id2)
914 return snap_id1 == snap_id2 ? 0 : -1;
918 * Search a snapshot context to see if the given snapshot id is
921 * Returns the position of the snapshot id in the array if it's found,
922 * or BAD_SNAP_INDEX otherwise.
924 * Note: The snapshot array is in kept sorted (by the osd) in
925 * reverse order, highest snapshot id first.
927 static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id)
929 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
932 found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps,
933 sizeof (snap_id), snapid_compare_reverse);
935 return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX;
938 static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
943 which = rbd_dev_snap_index(rbd_dev, snap_id);
944 if (which == BAD_SNAP_INDEX)
947 return _rbd_dev_v1_snap_name(rbd_dev, which);
950 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
952 if (snap_id == CEPH_NOSNAP)
953 return RBD_SNAP_HEAD_NAME;
955 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
956 if (rbd_dev->image_format == 1)
957 return rbd_dev_v1_snap_name(rbd_dev, snap_id);
959 return rbd_dev_v2_snap_name(rbd_dev, snap_id);
962 static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
965 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
966 if (snap_id == CEPH_NOSNAP) {
967 *snap_size = rbd_dev->header.image_size;
968 } else if (rbd_dev->image_format == 1) {
971 which = rbd_dev_snap_index(rbd_dev, snap_id);
972 if (which == BAD_SNAP_INDEX)
975 *snap_size = rbd_dev->header.snap_sizes[which];
980 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
989 static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
992 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
993 if (snap_id == CEPH_NOSNAP) {
994 *snap_features = rbd_dev->header.features;
995 } else if (rbd_dev->image_format == 1) {
996 *snap_features = 0; /* No features for format 1 */
1001 ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features);
1005 *snap_features = features;
1010 static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
1012 u64 snap_id = rbd_dev->spec->snap_id;
1017 ret = rbd_snap_size(rbd_dev, snap_id, &size);
1020 ret = rbd_snap_features(rbd_dev, snap_id, &features);
1024 rbd_dev->mapping.size = size;
1025 rbd_dev->mapping.features = features;
1030 static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
1032 rbd_dev->mapping.size = 0;
1033 rbd_dev->mapping.features = 0;
1036 static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset)
1043 name = kmem_cache_alloc(rbd_segment_name_cache, GFP_NOIO);
1046 segment = offset >> rbd_dev->header.obj_order;
1047 name_format = "%s.%012llx";
1048 if (rbd_dev->image_format == 2)
1049 name_format = "%s.%016llx";
1050 ret = snprintf(name, MAX_OBJ_NAME_SIZE + 1, name_format,
1051 rbd_dev->header.object_prefix, segment);
1052 if (ret < 0 || ret > MAX_OBJ_NAME_SIZE) {
1053 pr_err("error formatting segment name for #%llu (%d)\n",
1062 static void rbd_segment_name_free(const char *name)
1064 /* The explicit cast here is needed to drop the const qualifier */
1066 kmem_cache_free(rbd_segment_name_cache, (void *)name);
1069 static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset)
1071 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1073 return offset & (segment_size - 1);
1076 static u64 rbd_segment_length(struct rbd_device *rbd_dev,
1077 u64 offset, u64 length)
1079 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1081 offset &= segment_size - 1;
1083 rbd_assert(length <= U64_MAX - offset);
1084 if (offset + length > segment_size)
1085 length = segment_size - offset;
1091 * returns the size of an object in the image
1093 static u64 rbd_obj_bytes(struct rbd_image_header *header)
1095 return 1 << header->obj_order;
1102 static void bio_chain_put(struct bio *chain)
1108 chain = chain->bi_next;
1114 * zeros a bio chain, starting at specific offset
1116 static void zero_bio_chain(struct bio *chain, int start_ofs)
1119 unsigned long flags;
1125 bio_for_each_segment(bv, chain, i) {
1126 if (pos + bv->bv_len > start_ofs) {
1127 int remainder = max(start_ofs - pos, 0);
1128 buf = bvec_kmap_irq(bv, &flags);
1129 memset(buf + remainder, 0,
1130 bv->bv_len - remainder);
1131 bvec_kunmap_irq(buf, &flags);
1136 chain = chain->bi_next;
1141 * similar to zero_bio_chain(), zeros data defined by a page array,
1142 * starting at the given byte offset from the start of the array and
1143 * continuing up to the given end offset. The pages array is
1144 * assumed to be big enough to hold all bytes up to the end.
1146 static void zero_pages(struct page **pages, u64 offset, u64 end)
1148 struct page **page = &pages[offset >> PAGE_SHIFT];
1150 rbd_assert(end > offset);
1151 rbd_assert(end - offset <= (u64)SIZE_MAX);
1152 while (offset < end) {
1155 unsigned long flags;
1158 page_offset = (size_t)(offset & ~PAGE_MASK);
1159 length = min(PAGE_SIZE - page_offset, (size_t)(end - offset));
1160 local_irq_save(flags);
1161 kaddr = kmap_atomic(*page);
1162 memset(kaddr + page_offset, 0, length);
1163 kunmap_atomic(kaddr);
1164 local_irq_restore(flags);
1172 * Clone a portion of a bio, starting at the given byte offset
1173 * and continuing for the number of bytes indicated.
1175 static struct bio *bio_clone_range(struct bio *bio_src,
1176 unsigned int offset,
1184 unsigned short end_idx;
1185 unsigned short vcnt;
1188 /* Handle the easy case for the caller */
1190 if (!offset && len == bio_src->bi_size)
1191 return bio_clone(bio_src, gfpmask);
1193 if (WARN_ON_ONCE(!len))
1195 if (WARN_ON_ONCE(len > bio_src->bi_size))
1197 if (WARN_ON_ONCE(offset > bio_src->bi_size - len))
1200 /* Find first affected segment... */
1203 __bio_for_each_segment(bv, bio_src, idx, 0) {
1204 if (resid < bv->bv_len)
1206 resid -= bv->bv_len;
1210 /* ...and the last affected segment */
1213 __bio_for_each_segment(bv, bio_src, end_idx, idx) {
1214 if (resid <= bv->bv_len)
1216 resid -= bv->bv_len;
1218 vcnt = end_idx - idx + 1;
1220 /* Build the clone */
1222 bio = bio_alloc(gfpmask, (unsigned int) vcnt);
1224 return NULL; /* ENOMEM */
1226 bio->bi_bdev = bio_src->bi_bdev;
1227 bio->bi_sector = bio_src->bi_sector + (offset >> SECTOR_SHIFT);
1228 bio->bi_rw = bio_src->bi_rw;
1229 bio->bi_flags |= 1 << BIO_CLONED;
1232 * Copy over our part of the bio_vec, then update the first
1233 * and last (or only) entries.
1235 memcpy(&bio->bi_io_vec[0], &bio_src->bi_io_vec[idx],
1236 vcnt * sizeof (struct bio_vec));
1237 bio->bi_io_vec[0].bv_offset += voff;
1239 bio->bi_io_vec[0].bv_len -= voff;
1240 bio->bi_io_vec[vcnt - 1].bv_len = resid;
1242 bio->bi_io_vec[0].bv_len = len;
1245 bio->bi_vcnt = vcnt;
1253 * Clone a portion of a bio chain, starting at the given byte offset
1254 * into the first bio in the source chain and continuing for the
1255 * number of bytes indicated. The result is another bio chain of
1256 * exactly the given length, or a null pointer on error.
1258 * The bio_src and offset parameters are both in-out. On entry they
1259 * refer to the first source bio and the offset into that bio where
1260 * the start of data to be cloned is located.
1262 * On return, bio_src is updated to refer to the bio in the source
1263 * chain that contains first un-cloned byte, and *offset will
1264 * contain the offset of that byte within that bio.
1266 static struct bio *bio_chain_clone_range(struct bio **bio_src,
1267 unsigned int *offset,
1271 struct bio *bi = *bio_src;
1272 unsigned int off = *offset;
1273 struct bio *chain = NULL;
1276 /* Build up a chain of clone bios up to the limit */
1278 if (!bi || off >= bi->bi_size || !len)
1279 return NULL; /* Nothing to clone */
1283 unsigned int bi_size;
1287 rbd_warn(NULL, "bio_chain exhausted with %u left", len);
1288 goto out_err; /* EINVAL; ran out of bio's */
1290 bi_size = min_t(unsigned int, bi->bi_size - off, len);
1291 bio = bio_clone_range(bi, off, bi_size, gfpmask);
1293 goto out_err; /* ENOMEM */
1296 end = &bio->bi_next;
1299 if (off == bi->bi_size) {
1310 bio_chain_put(chain);
1316 * The default/initial value for all object request flags is 0. For
1317 * each flag, once its value is set to 1 it is never reset to 0
1320 static void obj_request_img_data_set(struct rbd_obj_request *obj_request)
1322 if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) {
1323 struct rbd_device *rbd_dev;
1325 rbd_dev = obj_request->img_request->rbd_dev;
1326 rbd_warn(rbd_dev, "obj_request %p already marked img_data\n",
1331 static bool obj_request_img_data_test(struct rbd_obj_request *obj_request)
1334 return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0;
1337 static void obj_request_done_set(struct rbd_obj_request *obj_request)
1339 if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) {
1340 struct rbd_device *rbd_dev = NULL;
1342 if (obj_request_img_data_test(obj_request))
1343 rbd_dev = obj_request->img_request->rbd_dev;
1344 rbd_warn(rbd_dev, "obj_request %p already marked done\n",
1349 static bool obj_request_done_test(struct rbd_obj_request *obj_request)
1352 return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0;
1356 * This sets the KNOWN flag after (possibly) setting the EXISTS
1357 * flag. The latter is set based on the "exists" value provided.
1359 * Note that for our purposes once an object exists it never goes
1360 * away again. It's possible that the response from two existence
1361 * checks are separated by the creation of the target object, and
1362 * the first ("doesn't exist") response arrives *after* the second
1363 * ("does exist"). In that case we ignore the second one.
1365 static void obj_request_existence_set(struct rbd_obj_request *obj_request,
1369 set_bit(OBJ_REQ_EXISTS, &obj_request->flags);
1370 set_bit(OBJ_REQ_KNOWN, &obj_request->flags);
1374 static bool obj_request_known_test(struct rbd_obj_request *obj_request)
1377 return test_bit(OBJ_REQ_KNOWN, &obj_request->flags) != 0;
1380 static bool obj_request_exists_test(struct rbd_obj_request *obj_request)
1383 return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0;
1386 static void rbd_obj_request_get(struct rbd_obj_request *obj_request)
1388 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1389 atomic_read(&obj_request->kref.refcount));
1390 kref_get(&obj_request->kref);
1393 static void rbd_obj_request_destroy(struct kref *kref);
1394 static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
1396 rbd_assert(obj_request != NULL);
1397 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1398 atomic_read(&obj_request->kref.refcount));
1399 kref_put(&obj_request->kref, rbd_obj_request_destroy);
1402 static bool img_request_child_test(struct rbd_img_request *img_request);
1403 static void rbd_parent_request_destroy(struct kref *kref);
1404 static void rbd_img_request_destroy(struct kref *kref);
1405 static void rbd_img_request_put(struct rbd_img_request *img_request)
1407 rbd_assert(img_request != NULL);
1408 dout("%s: img %p (was %d)\n", __func__, img_request,
1409 atomic_read(&img_request->kref.refcount));
1410 if (img_request_child_test(img_request))
1411 kref_put(&img_request->kref, rbd_parent_request_destroy);
1413 kref_put(&img_request->kref, rbd_img_request_destroy);
1416 static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
1417 struct rbd_obj_request *obj_request)
1419 rbd_assert(obj_request->img_request == NULL);
1421 /* Image request now owns object's original reference */
1422 obj_request->img_request = img_request;
1423 obj_request->which = img_request->obj_request_count;
1424 rbd_assert(!obj_request_img_data_test(obj_request));
1425 obj_request_img_data_set(obj_request);
1426 rbd_assert(obj_request->which != BAD_WHICH);
1427 img_request->obj_request_count++;
1428 list_add_tail(&obj_request->links, &img_request->obj_requests);
1429 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1430 obj_request->which);
1433 static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
1434 struct rbd_obj_request *obj_request)
1436 rbd_assert(obj_request->which != BAD_WHICH);
1438 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1439 obj_request->which);
1440 list_del(&obj_request->links);
1441 rbd_assert(img_request->obj_request_count > 0);
1442 img_request->obj_request_count--;
1443 rbd_assert(obj_request->which == img_request->obj_request_count);
1444 obj_request->which = BAD_WHICH;
1445 rbd_assert(obj_request_img_data_test(obj_request));
1446 rbd_assert(obj_request->img_request == img_request);
1447 obj_request->img_request = NULL;
1448 obj_request->callback = NULL;
1449 rbd_obj_request_put(obj_request);
1452 static bool obj_request_type_valid(enum obj_request_type type)
1455 case OBJ_REQUEST_NODATA:
1456 case OBJ_REQUEST_BIO:
1457 case OBJ_REQUEST_PAGES:
1464 static int rbd_obj_request_submit(struct ceph_osd_client *osdc,
1465 struct rbd_obj_request *obj_request)
1467 dout("%s: osdc %p obj %p\n", __func__, osdc, obj_request);
1469 return ceph_osdc_start_request(osdc, obj_request->osd_req, false);
1472 static void rbd_img_request_complete(struct rbd_img_request *img_request)
1475 dout("%s: img %p\n", __func__, img_request);
1478 * If no error occurred, compute the aggregate transfer
1479 * count for the image request. We could instead use
1480 * atomic64_cmpxchg() to update it as each object request
1481 * completes; not clear which way is better off hand.
1483 if (!img_request->result) {
1484 struct rbd_obj_request *obj_request;
1487 for_each_obj_request(img_request, obj_request)
1488 xferred += obj_request->xferred;
1489 img_request->xferred = xferred;
1492 if (img_request->callback)
1493 img_request->callback(img_request);
1495 rbd_img_request_put(img_request);
1498 /* Caller is responsible for rbd_obj_request_destroy(obj_request) */
1500 static int rbd_obj_request_wait(struct rbd_obj_request *obj_request)
1502 dout("%s: obj %p\n", __func__, obj_request);
1504 return wait_for_completion_interruptible(&obj_request->completion);
1508 * The default/initial value for all image request flags is 0. Each
1509 * is conditionally set to 1 at image request initialization time
1510 * and currently never change thereafter.
1512 static void img_request_write_set(struct rbd_img_request *img_request)
1514 set_bit(IMG_REQ_WRITE, &img_request->flags);
1518 static bool img_request_write_test(struct rbd_img_request *img_request)
1521 return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0;
1524 static void img_request_child_set(struct rbd_img_request *img_request)
1526 set_bit(IMG_REQ_CHILD, &img_request->flags);
1530 static void img_request_child_clear(struct rbd_img_request *img_request)
1532 clear_bit(IMG_REQ_CHILD, &img_request->flags);
1536 static bool img_request_child_test(struct rbd_img_request *img_request)
1539 return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0;
1542 static void img_request_layered_set(struct rbd_img_request *img_request)
1544 set_bit(IMG_REQ_LAYERED, &img_request->flags);
1548 static void img_request_layered_clear(struct rbd_img_request *img_request)
1550 clear_bit(IMG_REQ_LAYERED, &img_request->flags);
1554 static bool img_request_layered_test(struct rbd_img_request *img_request)
1557 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
1561 rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
1563 u64 xferred = obj_request->xferred;
1564 u64 length = obj_request->length;
1566 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1567 obj_request, obj_request->img_request, obj_request->result,
1570 * ENOENT means a hole in the image. We zero-fill the
1571 * entire length of the request. A short read also implies
1572 * zero-fill to the end of the request. Either way we
1573 * update the xferred count to indicate the whole request
1576 rbd_assert(obj_request->type != OBJ_REQUEST_NODATA);
1577 if (obj_request->result == -ENOENT) {
1578 if (obj_request->type == OBJ_REQUEST_BIO)
1579 zero_bio_chain(obj_request->bio_list, 0);
1581 zero_pages(obj_request->pages, 0, length);
1582 obj_request->result = 0;
1583 obj_request->xferred = length;
1584 } else if (xferred < length && !obj_request->result) {
1585 if (obj_request->type == OBJ_REQUEST_BIO)
1586 zero_bio_chain(obj_request->bio_list, xferred);
1588 zero_pages(obj_request->pages, xferred, length);
1589 obj_request->xferred = length;
1591 obj_request_done_set(obj_request);
1594 static void rbd_obj_request_complete(struct rbd_obj_request *obj_request)
1596 dout("%s: obj %p cb %p\n", __func__, obj_request,
1597 obj_request->callback);
1598 if (obj_request->callback)
1599 obj_request->callback(obj_request);
1601 complete_all(&obj_request->completion);
1604 static void rbd_osd_trivial_callback(struct rbd_obj_request *obj_request)
1606 dout("%s: obj %p\n", __func__, obj_request);
1607 obj_request_done_set(obj_request);
1610 static void rbd_osd_read_callback(struct rbd_obj_request *obj_request)
1612 struct rbd_img_request *img_request = NULL;
1613 struct rbd_device *rbd_dev = NULL;
1614 bool layered = false;
1616 if (obj_request_img_data_test(obj_request)) {
1617 img_request = obj_request->img_request;
1618 layered = img_request && img_request_layered_test(img_request);
1619 rbd_dev = img_request->rbd_dev;
1622 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1623 obj_request, img_request, obj_request->result,
1624 obj_request->xferred, obj_request->length);
1625 if (layered && obj_request->result == -ENOENT &&
1626 obj_request->img_offset < rbd_dev->parent_overlap)
1627 rbd_img_parent_read(obj_request);
1628 else if (img_request)
1629 rbd_img_obj_request_read_callback(obj_request);
1631 obj_request_done_set(obj_request);
1634 static void rbd_osd_write_callback(struct rbd_obj_request *obj_request)
1636 dout("%s: obj %p result %d %llu\n", __func__, obj_request,
1637 obj_request->result, obj_request->length);
1639 * There is no such thing as a successful short write. Set
1640 * it to our originally-requested length.
1642 obj_request->xferred = obj_request->length;
1643 obj_request_done_set(obj_request);
1647 * For a simple stat call there's nothing to do. We'll do more if
1648 * this is part of a write sequence for a layered image.
1650 static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request)
1652 dout("%s: obj %p\n", __func__, obj_request);
1653 obj_request_done_set(obj_request);
1656 static void rbd_osd_req_callback(struct ceph_osd_request *osd_req,
1657 struct ceph_msg *msg)
1659 struct rbd_obj_request *obj_request = osd_req->r_priv;
1662 dout("%s: osd_req %p msg %p\n", __func__, osd_req, msg);
1663 rbd_assert(osd_req == obj_request->osd_req);
1664 if (obj_request_img_data_test(obj_request)) {
1665 rbd_assert(obj_request->img_request);
1666 rbd_assert(obj_request->which != BAD_WHICH);
1668 rbd_assert(obj_request->which == BAD_WHICH);
1671 if (osd_req->r_result < 0)
1672 obj_request->result = osd_req->r_result;
1674 BUG_ON(osd_req->r_num_ops > 2);
1677 * We support a 64-bit length, but ultimately it has to be
1678 * passed to blk_end_request(), which takes an unsigned int.
1680 obj_request->xferred = osd_req->r_reply_op_len[0];
1681 rbd_assert(obj_request->xferred < (u64)UINT_MAX);
1682 opcode = osd_req->r_ops[0].op;
1684 case CEPH_OSD_OP_READ:
1685 rbd_osd_read_callback(obj_request);
1687 case CEPH_OSD_OP_WRITE:
1688 rbd_osd_write_callback(obj_request);
1690 case CEPH_OSD_OP_STAT:
1691 rbd_osd_stat_callback(obj_request);
1693 case CEPH_OSD_OP_CALL:
1694 case CEPH_OSD_OP_NOTIFY_ACK:
1695 case CEPH_OSD_OP_WATCH:
1696 rbd_osd_trivial_callback(obj_request);
1699 rbd_warn(NULL, "%s: unsupported op %hu\n",
1700 obj_request->object_name, (unsigned short) opcode);
1704 if (obj_request_done_test(obj_request))
1705 rbd_obj_request_complete(obj_request);
1708 static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request)
1710 struct rbd_img_request *img_request = obj_request->img_request;
1711 struct ceph_osd_request *osd_req = obj_request->osd_req;
1714 rbd_assert(osd_req != NULL);
1716 snap_id = img_request ? img_request->snap_id : CEPH_NOSNAP;
1717 ceph_osdc_build_request(osd_req, obj_request->offset,
1718 NULL, snap_id, NULL);
1721 static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request)
1723 struct rbd_img_request *img_request = obj_request->img_request;
1724 struct ceph_osd_request *osd_req = obj_request->osd_req;
1725 struct ceph_snap_context *snapc;
1726 struct timespec mtime = CURRENT_TIME;
1728 rbd_assert(osd_req != NULL);
1730 snapc = img_request ? img_request->snapc : NULL;
1731 ceph_osdc_build_request(osd_req, obj_request->offset,
1732 snapc, CEPH_NOSNAP, &mtime);
1735 static struct ceph_osd_request *rbd_osd_req_create(
1736 struct rbd_device *rbd_dev,
1738 struct rbd_obj_request *obj_request)
1740 struct ceph_snap_context *snapc = NULL;
1741 struct ceph_osd_client *osdc;
1742 struct ceph_osd_request *osd_req;
1744 if (obj_request_img_data_test(obj_request)) {
1745 struct rbd_img_request *img_request = obj_request->img_request;
1747 rbd_assert(write_request ==
1748 img_request_write_test(img_request));
1750 snapc = img_request->snapc;
1753 /* Allocate and initialize the request, for the single op */
1755 osdc = &rbd_dev->rbd_client->client->osdc;
1756 osd_req = ceph_osdc_alloc_request(osdc, snapc, 1, false, GFP_ATOMIC);
1758 return NULL; /* ENOMEM */
1761 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1763 osd_req->r_flags = CEPH_OSD_FLAG_READ;
1765 osd_req->r_callback = rbd_osd_req_callback;
1766 osd_req->r_priv = obj_request;
1768 osd_req->r_oid_len = strlen(obj_request->object_name);
1769 rbd_assert(osd_req->r_oid_len < sizeof (osd_req->r_oid));
1770 memcpy(osd_req->r_oid, obj_request->object_name, osd_req->r_oid_len);
1772 osd_req->r_file_layout = rbd_dev->layout; /* struct */
1778 * Create a copyup osd request based on the information in the
1779 * object request supplied. A copyup request has two osd ops,
1780 * a copyup method call, and a "normal" write request.
1782 static struct ceph_osd_request *
1783 rbd_osd_req_create_copyup(struct rbd_obj_request *obj_request)
1785 struct rbd_img_request *img_request;
1786 struct ceph_snap_context *snapc;
1787 struct rbd_device *rbd_dev;
1788 struct ceph_osd_client *osdc;
1789 struct ceph_osd_request *osd_req;
1791 rbd_assert(obj_request_img_data_test(obj_request));
1792 img_request = obj_request->img_request;
1793 rbd_assert(img_request);
1794 rbd_assert(img_request_write_test(img_request));
1796 /* Allocate and initialize the request, for the two ops */
1798 snapc = img_request->snapc;
1799 rbd_dev = img_request->rbd_dev;
1800 osdc = &rbd_dev->rbd_client->client->osdc;
1801 osd_req = ceph_osdc_alloc_request(osdc, snapc, 2, false, GFP_ATOMIC);
1803 return NULL; /* ENOMEM */
1805 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1806 osd_req->r_callback = rbd_osd_req_callback;
1807 osd_req->r_priv = obj_request;
1809 osd_req->r_oid_len = strlen(obj_request->object_name);
1810 rbd_assert(osd_req->r_oid_len < sizeof (osd_req->r_oid));
1811 memcpy(osd_req->r_oid, obj_request->object_name, osd_req->r_oid_len);
1813 osd_req->r_file_layout = rbd_dev->layout; /* struct */
1819 static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req)
1821 ceph_osdc_put_request(osd_req);
1824 /* object_name is assumed to be a non-null pointer and NUL-terminated */
1826 static struct rbd_obj_request *rbd_obj_request_create(const char *object_name,
1827 u64 offset, u64 length,
1828 enum obj_request_type type)
1830 struct rbd_obj_request *obj_request;
1834 rbd_assert(obj_request_type_valid(type));
1836 size = strlen(object_name) + 1;
1837 name = kmalloc(size, GFP_KERNEL);
1841 obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_KERNEL);
1847 obj_request->object_name = memcpy(name, object_name, size);
1848 obj_request->offset = offset;
1849 obj_request->length = length;
1850 obj_request->flags = 0;
1851 obj_request->which = BAD_WHICH;
1852 obj_request->type = type;
1853 INIT_LIST_HEAD(&obj_request->links);
1854 init_completion(&obj_request->completion);
1855 kref_init(&obj_request->kref);
1857 dout("%s: \"%s\" %llu/%llu %d -> obj %p\n", __func__, object_name,
1858 offset, length, (int)type, obj_request);
1863 static void rbd_obj_request_destroy(struct kref *kref)
1865 struct rbd_obj_request *obj_request;
1867 obj_request = container_of(kref, struct rbd_obj_request, kref);
1869 dout("%s: obj %p\n", __func__, obj_request);
1871 rbd_assert(obj_request->img_request == NULL);
1872 rbd_assert(obj_request->which == BAD_WHICH);
1874 if (obj_request->osd_req)
1875 rbd_osd_req_destroy(obj_request->osd_req);
1877 rbd_assert(obj_request_type_valid(obj_request->type));
1878 switch (obj_request->type) {
1879 case OBJ_REQUEST_NODATA:
1880 break; /* Nothing to do */
1881 case OBJ_REQUEST_BIO:
1882 if (obj_request->bio_list)
1883 bio_chain_put(obj_request->bio_list);
1885 case OBJ_REQUEST_PAGES:
1886 if (obj_request->pages)
1887 ceph_release_page_vector(obj_request->pages,
1888 obj_request->page_count);
1892 kfree(obj_request->object_name);
1893 obj_request->object_name = NULL;
1894 kmem_cache_free(rbd_obj_request_cache, obj_request);
1897 /* It's OK to call this for a device with no parent */
1899 static void rbd_spec_put(struct rbd_spec *spec);
1900 static void rbd_dev_unparent(struct rbd_device *rbd_dev)
1902 rbd_dev_remove_parent(rbd_dev);
1903 rbd_spec_put(rbd_dev->parent_spec);
1904 rbd_dev->parent_spec = NULL;
1905 rbd_dev->parent_overlap = 0;
1909 * Parent image reference counting is used to determine when an
1910 * image's parent fields can be safely torn down--after there are no
1911 * more in-flight requests to the parent image. When the last
1912 * reference is dropped, cleaning them up is safe.
1914 static void rbd_dev_parent_put(struct rbd_device *rbd_dev)
1918 if (!rbd_dev->parent_spec)
1921 counter = atomic_dec_return_safe(&rbd_dev->parent_ref);
1925 /* Last reference; clean up parent data structures */
1928 rbd_dev_unparent(rbd_dev);
1930 rbd_warn(rbd_dev, "parent reference underflow\n");
1934 * If an image has a non-zero parent overlap, get a reference to its
1937 * We must get the reference before checking for the overlap to
1938 * coordinate properly with zeroing the parent overlap in
1939 * rbd_dev_v2_parent_info() when an image gets flattened. We
1940 * drop it again if there is no overlap.
1942 * Returns true if the rbd device has a parent with a non-zero
1943 * overlap and a reference for it was successfully taken, or
1946 static bool rbd_dev_parent_get(struct rbd_device *rbd_dev)
1950 if (!rbd_dev->parent_spec)
1953 counter = atomic_inc_return_safe(&rbd_dev->parent_ref);
1954 if (counter > 0 && rbd_dev->parent_overlap)
1957 /* Image was flattened, but parent is not yet torn down */
1960 rbd_warn(rbd_dev, "parent reference overflow\n");
1966 * Caller is responsible for filling in the list of object requests
1967 * that comprises the image request, and the Linux request pointer
1968 * (if there is one).
1970 static struct rbd_img_request *rbd_img_request_create(
1971 struct rbd_device *rbd_dev,
1972 u64 offset, u64 length,
1975 struct rbd_img_request *img_request;
1977 img_request = kmem_cache_alloc(rbd_img_request_cache, GFP_ATOMIC);
1981 if (write_request) {
1982 down_read(&rbd_dev->header_rwsem);
1983 ceph_get_snap_context(rbd_dev->header.snapc);
1984 up_read(&rbd_dev->header_rwsem);
1987 img_request->rq = NULL;
1988 img_request->rbd_dev = rbd_dev;
1989 img_request->offset = offset;
1990 img_request->length = length;
1991 img_request->flags = 0;
1992 if (write_request) {
1993 img_request_write_set(img_request);
1994 img_request->snapc = rbd_dev->header.snapc;
1996 img_request->snap_id = rbd_dev->spec->snap_id;
1998 if (rbd_dev_parent_get(rbd_dev))
1999 img_request_layered_set(img_request);
2000 spin_lock_init(&img_request->completion_lock);
2001 img_request->next_completion = 0;
2002 img_request->callback = NULL;
2003 img_request->result = 0;
2004 img_request->obj_request_count = 0;
2005 INIT_LIST_HEAD(&img_request->obj_requests);
2006 kref_init(&img_request->kref);
2008 dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev,
2009 write_request ? "write" : "read", offset, length,
2015 static void rbd_img_request_destroy(struct kref *kref)
2017 struct rbd_img_request *img_request;
2018 struct rbd_obj_request *obj_request;
2019 struct rbd_obj_request *next_obj_request;
2021 img_request = container_of(kref, struct rbd_img_request, kref);
2023 dout("%s: img %p\n", __func__, img_request);
2025 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2026 rbd_img_obj_request_del(img_request, obj_request);
2027 rbd_assert(img_request->obj_request_count == 0);
2029 if (img_request_layered_test(img_request)) {
2030 img_request_layered_clear(img_request);
2031 rbd_dev_parent_put(img_request->rbd_dev);
2034 if (img_request_write_test(img_request))
2035 ceph_put_snap_context(img_request->snapc);
2037 kmem_cache_free(rbd_img_request_cache, img_request);
2040 static struct rbd_img_request *rbd_parent_request_create(
2041 struct rbd_obj_request *obj_request,
2042 u64 img_offset, u64 length)
2044 struct rbd_img_request *parent_request;
2045 struct rbd_device *rbd_dev;
2047 rbd_assert(obj_request->img_request);
2048 rbd_dev = obj_request->img_request->rbd_dev;
2050 parent_request = rbd_img_request_create(rbd_dev->parent,
2051 img_offset, length, false);
2052 if (!parent_request)
2055 img_request_child_set(parent_request);
2056 rbd_obj_request_get(obj_request);
2057 parent_request->obj_request = obj_request;
2059 return parent_request;
2062 static void rbd_parent_request_destroy(struct kref *kref)
2064 struct rbd_img_request *parent_request;
2065 struct rbd_obj_request *orig_request;
2067 parent_request = container_of(kref, struct rbd_img_request, kref);
2068 orig_request = parent_request->obj_request;
2070 parent_request->obj_request = NULL;
2071 rbd_obj_request_put(orig_request);
2072 img_request_child_clear(parent_request);
2074 rbd_img_request_destroy(kref);
2077 static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request)
2079 struct rbd_img_request *img_request;
2080 unsigned int xferred;
2084 rbd_assert(obj_request_img_data_test(obj_request));
2085 img_request = obj_request->img_request;
2087 rbd_assert(obj_request->xferred <= (u64)UINT_MAX);
2088 xferred = (unsigned int)obj_request->xferred;
2089 result = obj_request->result;
2091 struct rbd_device *rbd_dev = img_request->rbd_dev;
2093 rbd_warn(rbd_dev, "%s %llx at %llx (%llx)\n",
2094 img_request_write_test(img_request) ? "write" : "read",
2095 obj_request->length, obj_request->img_offset,
2096 obj_request->offset);
2097 rbd_warn(rbd_dev, " result %d xferred %x\n",
2099 if (!img_request->result)
2100 img_request->result = result;
2103 /* Image object requests don't own their page array */
2105 if (obj_request->type == OBJ_REQUEST_PAGES) {
2106 obj_request->pages = NULL;
2107 obj_request->page_count = 0;
2110 if (img_request_child_test(img_request)) {
2111 rbd_assert(img_request->obj_request != NULL);
2112 more = obj_request->which < img_request->obj_request_count - 1;
2114 rbd_assert(img_request->rq != NULL);
2115 more = blk_end_request(img_request->rq, result, xferred);
2121 static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
2123 struct rbd_img_request *img_request;
2124 u32 which = obj_request->which;
2127 rbd_assert(obj_request_img_data_test(obj_request));
2128 img_request = obj_request->img_request;
2130 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
2131 rbd_assert(img_request != NULL);
2132 rbd_assert(img_request->obj_request_count > 0);
2133 rbd_assert(which != BAD_WHICH);
2134 rbd_assert(which < img_request->obj_request_count);
2135 rbd_assert(which >= img_request->next_completion);
2137 spin_lock_irq(&img_request->completion_lock);
2138 if (which != img_request->next_completion)
2141 for_each_obj_request_from(img_request, obj_request) {
2143 rbd_assert(which < img_request->obj_request_count);
2145 if (!obj_request_done_test(obj_request))
2147 more = rbd_img_obj_end_request(obj_request);
2151 rbd_assert(more ^ (which == img_request->obj_request_count));
2152 img_request->next_completion = which;
2154 spin_unlock_irq(&img_request->completion_lock);
2157 rbd_img_request_complete(img_request);
2161 * Split up an image request into one or more object requests, each
2162 * to a different object. The "type" parameter indicates whether
2163 * "data_desc" is the pointer to the head of a list of bio
2164 * structures, or the base of a page array. In either case this
2165 * function assumes data_desc describes memory sufficient to hold
2166 * all data described by the image request.
2168 static int rbd_img_request_fill(struct rbd_img_request *img_request,
2169 enum obj_request_type type,
2172 struct rbd_device *rbd_dev = img_request->rbd_dev;
2173 struct rbd_obj_request *obj_request = NULL;
2174 struct rbd_obj_request *next_obj_request;
2175 bool write_request = img_request_write_test(img_request);
2176 struct bio *bio_list;
2177 unsigned int bio_offset = 0;
2178 struct page **pages;
2183 dout("%s: img %p type %d data_desc %p\n", __func__, img_request,
2184 (int)type, data_desc);
2186 opcode = write_request ? CEPH_OSD_OP_WRITE : CEPH_OSD_OP_READ;
2187 img_offset = img_request->offset;
2188 resid = img_request->length;
2189 rbd_assert(resid > 0);
2191 if (type == OBJ_REQUEST_BIO) {
2192 bio_list = data_desc;
2193 rbd_assert(img_offset == bio_list->bi_sector << SECTOR_SHIFT);
2195 rbd_assert(type == OBJ_REQUEST_PAGES);
2200 struct ceph_osd_request *osd_req;
2201 const char *object_name;
2205 object_name = rbd_segment_name(rbd_dev, img_offset);
2208 offset = rbd_segment_offset(rbd_dev, img_offset);
2209 length = rbd_segment_length(rbd_dev, img_offset, resid);
2210 obj_request = rbd_obj_request_create(object_name,
2211 offset, length, type);
2212 /* object request has its own copy of the object name */
2213 rbd_segment_name_free(object_name);
2217 if (type == OBJ_REQUEST_BIO) {
2218 unsigned int clone_size;
2220 rbd_assert(length <= (u64)UINT_MAX);
2221 clone_size = (unsigned int)length;
2222 obj_request->bio_list =
2223 bio_chain_clone_range(&bio_list,
2227 if (!obj_request->bio_list)
2230 unsigned int page_count;
2232 obj_request->pages = pages;
2233 page_count = (u32)calc_pages_for(offset, length);
2234 obj_request->page_count = page_count;
2235 if ((offset + length) & ~PAGE_MASK)
2236 page_count--; /* more on last page */
2237 pages += page_count;
2240 osd_req = rbd_osd_req_create(rbd_dev, write_request,
2244 obj_request->osd_req = osd_req;
2245 obj_request->callback = rbd_img_obj_callback;
2247 osd_req_op_extent_init(osd_req, 0, opcode, offset, length,
2249 if (type == OBJ_REQUEST_BIO)
2250 osd_req_op_extent_osd_data_bio(osd_req, 0,
2251 obj_request->bio_list, length);
2253 osd_req_op_extent_osd_data_pages(osd_req, 0,
2254 obj_request->pages, length,
2255 offset & ~PAGE_MASK, false, false);
2258 rbd_osd_req_format_write(obj_request);
2260 rbd_osd_req_format_read(obj_request);
2262 obj_request->img_offset = img_offset;
2263 rbd_img_obj_request_add(img_request, obj_request);
2265 img_offset += length;
2272 rbd_obj_request_put(obj_request);
2274 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2275 rbd_obj_request_put(obj_request);
2281 rbd_img_obj_copyup_callback(struct rbd_obj_request *obj_request)
2283 struct rbd_img_request *img_request;
2284 struct rbd_device *rbd_dev;
2285 struct page **pages;
2288 rbd_assert(obj_request->type == OBJ_REQUEST_BIO);
2289 rbd_assert(obj_request_img_data_test(obj_request));
2290 img_request = obj_request->img_request;
2291 rbd_assert(img_request);
2293 rbd_dev = img_request->rbd_dev;
2294 rbd_assert(rbd_dev);
2296 pages = obj_request->copyup_pages;
2297 rbd_assert(pages != NULL);
2298 obj_request->copyup_pages = NULL;
2299 page_count = obj_request->copyup_page_count;
2300 rbd_assert(page_count);
2301 obj_request->copyup_page_count = 0;
2302 ceph_release_page_vector(pages, page_count);
2305 * We want the transfer count to reflect the size of the
2306 * original write request. There is no such thing as a
2307 * successful short write, so if the request was successful
2308 * we can just set it to the originally-requested length.
2310 if (!obj_request->result)
2311 obj_request->xferred = obj_request->length;
2313 /* Finish up with the normal image object callback */
2315 rbd_img_obj_callback(obj_request);
2319 rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request)
2321 struct rbd_obj_request *orig_request;
2322 struct ceph_osd_request *osd_req;
2323 struct ceph_osd_client *osdc;
2324 struct rbd_device *rbd_dev;
2325 struct page **pages;
2332 rbd_assert(img_request_child_test(img_request));
2334 /* First get what we need from the image request */
2336 pages = img_request->copyup_pages;
2337 rbd_assert(pages != NULL);
2338 img_request->copyup_pages = NULL;
2339 page_count = img_request->copyup_page_count;
2340 rbd_assert(page_count);
2341 img_request->copyup_page_count = 0;
2343 orig_request = img_request->obj_request;
2344 rbd_assert(orig_request != NULL);
2345 rbd_assert(obj_request_type_valid(orig_request->type));
2346 img_result = img_request->result;
2347 parent_length = img_request->length;
2348 rbd_assert(parent_length == img_request->xferred);
2349 rbd_img_request_put(img_request);
2351 rbd_assert(orig_request->img_request);
2352 rbd_dev = orig_request->img_request->rbd_dev;
2353 rbd_assert(rbd_dev);
2356 * If the overlap has become 0 (most likely because the
2357 * image has been flattened) we need to free the pages
2358 * and re-submit the original write request.
2360 if (!rbd_dev->parent_overlap) {
2361 struct ceph_osd_client *osdc;
2363 ceph_release_page_vector(pages, page_count);
2364 osdc = &rbd_dev->rbd_client->client->osdc;
2365 img_result = rbd_obj_request_submit(osdc, orig_request);
2374 * The original osd request is of no use to use any more.
2375 * We need a new one that can hold the two ops in a copyup
2376 * request. Allocate the new copyup osd request for the
2377 * original request, and release the old one.
2379 img_result = -ENOMEM;
2380 osd_req = rbd_osd_req_create_copyup(orig_request);
2383 rbd_osd_req_destroy(orig_request->osd_req);
2384 orig_request->osd_req = osd_req;
2385 orig_request->copyup_pages = pages;
2386 orig_request->copyup_page_count = page_count;
2388 /* Initialize the copyup op */
2390 osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup");
2391 osd_req_op_cls_request_data_pages(osd_req, 0, pages, parent_length, 0,
2394 /* Then the original write request op */
2396 offset = orig_request->offset;
2397 length = orig_request->length;
2398 osd_req_op_extent_init(osd_req, 1, CEPH_OSD_OP_WRITE,
2399 offset, length, 0, 0);
2400 if (orig_request->type == OBJ_REQUEST_BIO)
2401 osd_req_op_extent_osd_data_bio(osd_req, 1,
2402 orig_request->bio_list, length);
2404 osd_req_op_extent_osd_data_pages(osd_req, 1,
2405 orig_request->pages, length,
2406 offset & ~PAGE_MASK, false, false);
2408 rbd_osd_req_format_write(orig_request);
2410 /* All set, send it off. */
2412 orig_request->callback = rbd_img_obj_copyup_callback;
2413 osdc = &rbd_dev->rbd_client->client->osdc;
2414 img_result = rbd_obj_request_submit(osdc, orig_request);
2418 /* Record the error code and complete the request */
2420 orig_request->result = img_result;
2421 orig_request->xferred = 0;
2422 obj_request_done_set(orig_request);
2423 rbd_obj_request_complete(orig_request);
2427 * Read from the parent image the range of data that covers the
2428 * entire target of the given object request. This is used for
2429 * satisfying a layered image write request when the target of an
2430 * object request from the image request does not exist.
2432 * A page array big enough to hold the returned data is allocated
2433 * and supplied to rbd_img_request_fill() as the "data descriptor."
2434 * When the read completes, this page array will be transferred to
2435 * the original object request for the copyup operation.
2437 * If an error occurs, record it as the result of the original
2438 * object request and mark it done so it gets completed.
2440 static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request)
2442 struct rbd_img_request *img_request = NULL;
2443 struct rbd_img_request *parent_request = NULL;
2444 struct rbd_device *rbd_dev;
2447 struct page **pages = NULL;
2451 rbd_assert(obj_request_img_data_test(obj_request));
2452 rbd_assert(obj_request_type_valid(obj_request->type));
2454 img_request = obj_request->img_request;
2455 rbd_assert(img_request != NULL);
2456 rbd_dev = img_request->rbd_dev;
2457 rbd_assert(rbd_dev->parent != NULL);
2460 * Determine the byte range covered by the object in the
2461 * child image to which the original request was to be sent.
2463 img_offset = obj_request->img_offset - obj_request->offset;
2464 length = (u64)1 << rbd_dev->header.obj_order;
2467 * There is no defined parent data beyond the parent
2468 * overlap, so limit what we read at that boundary if
2471 if (img_offset + length > rbd_dev->parent_overlap) {
2472 rbd_assert(img_offset < rbd_dev->parent_overlap);
2473 length = rbd_dev->parent_overlap - img_offset;
2477 * Allocate a page array big enough to receive the data read
2480 page_count = (u32)calc_pages_for(0, length);
2481 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2482 if (IS_ERR(pages)) {
2483 result = PTR_ERR(pages);
2489 parent_request = rbd_parent_request_create(obj_request,
2490 img_offset, length);
2491 if (!parent_request)
2494 result = rbd_img_request_fill(parent_request, OBJ_REQUEST_PAGES, pages);
2497 parent_request->copyup_pages = pages;
2498 parent_request->copyup_page_count = page_count;
2500 parent_request->callback = rbd_img_obj_parent_read_full_callback;
2501 result = rbd_img_request_submit(parent_request);
2505 parent_request->copyup_pages = NULL;
2506 parent_request->copyup_page_count = 0;
2507 parent_request->obj_request = NULL;
2508 rbd_obj_request_put(obj_request);
2511 ceph_release_page_vector(pages, page_count);
2513 rbd_img_request_put(parent_request);
2514 obj_request->result = result;
2515 obj_request->xferred = 0;
2516 obj_request_done_set(obj_request);
2521 static void rbd_img_obj_exists_callback(struct rbd_obj_request *obj_request)
2523 struct rbd_obj_request *orig_request;
2524 struct rbd_device *rbd_dev;
2527 rbd_assert(!obj_request_img_data_test(obj_request));
2530 * All we need from the object request is the original
2531 * request and the result of the STAT op. Grab those, then
2532 * we're done with the request.
2534 orig_request = obj_request->obj_request;
2535 obj_request->obj_request = NULL;
2536 rbd_assert(orig_request);
2537 rbd_assert(orig_request->img_request);
2539 result = obj_request->result;
2540 obj_request->result = 0;
2542 dout("%s: obj %p for obj %p result %d %llu/%llu\n", __func__,
2543 obj_request, orig_request, result,
2544 obj_request->xferred, obj_request->length);
2545 rbd_obj_request_put(obj_request);
2548 * If the overlap has become 0 (most likely because the
2549 * image has been flattened) we need to free the pages
2550 * and re-submit the original write request.
2552 rbd_dev = orig_request->img_request->rbd_dev;
2553 if (!rbd_dev->parent_overlap) {
2554 struct ceph_osd_client *osdc;
2556 rbd_obj_request_put(orig_request);
2557 osdc = &rbd_dev->rbd_client->client->osdc;
2558 result = rbd_obj_request_submit(osdc, orig_request);
2564 * Our only purpose here is to determine whether the object
2565 * exists, and we don't want to treat the non-existence as
2566 * an error. If something else comes back, transfer the
2567 * error to the original request and complete it now.
2570 obj_request_existence_set(orig_request, true);
2571 } else if (result == -ENOENT) {
2572 obj_request_existence_set(orig_request, false);
2573 } else if (result) {
2574 orig_request->result = result;
2579 * Resubmit the original request now that we have recorded
2580 * whether the target object exists.
2582 orig_request->result = rbd_img_obj_request_submit(orig_request);
2584 if (orig_request->result)
2585 rbd_obj_request_complete(orig_request);
2586 rbd_obj_request_put(orig_request);
2589 static int rbd_img_obj_exists_submit(struct rbd_obj_request *obj_request)
2591 struct rbd_obj_request *stat_request;
2592 struct rbd_device *rbd_dev;
2593 struct ceph_osd_client *osdc;
2594 struct page **pages = NULL;
2600 * The response data for a STAT call consists of:
2607 size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32);
2608 page_count = (u32)calc_pages_for(0, size);
2609 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2611 return PTR_ERR(pages);
2614 stat_request = rbd_obj_request_create(obj_request->object_name, 0, 0,
2619 rbd_obj_request_get(obj_request);
2620 stat_request->obj_request = obj_request;
2621 stat_request->pages = pages;
2622 stat_request->page_count = page_count;
2624 rbd_assert(obj_request->img_request);
2625 rbd_dev = obj_request->img_request->rbd_dev;
2626 stat_request->osd_req = rbd_osd_req_create(rbd_dev, false,
2628 if (!stat_request->osd_req)
2630 stat_request->callback = rbd_img_obj_exists_callback;
2632 osd_req_op_init(stat_request->osd_req, 0, CEPH_OSD_OP_STAT);
2633 osd_req_op_raw_data_in_pages(stat_request->osd_req, 0, pages, size, 0,
2635 rbd_osd_req_format_read(stat_request);
2637 osdc = &rbd_dev->rbd_client->client->osdc;
2638 ret = rbd_obj_request_submit(osdc, stat_request);
2641 rbd_obj_request_put(obj_request);
2646 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request)
2648 struct rbd_img_request *img_request;
2649 struct rbd_device *rbd_dev;
2652 rbd_assert(obj_request_img_data_test(obj_request));
2654 img_request = obj_request->img_request;
2655 rbd_assert(img_request);
2656 rbd_dev = img_request->rbd_dev;
2659 * Only writes to layered images need special handling.
2660 * Reads and non-layered writes are simple object requests.
2661 * Layered writes that start beyond the end of the overlap
2662 * with the parent have no parent data, so they too are
2663 * simple object requests. Finally, if the target object is
2664 * known to already exist, its parent data has already been
2665 * copied, so a write to the object can also be handled as a
2666 * simple object request.
2668 if (!img_request_write_test(img_request) ||
2669 !img_request_layered_test(img_request) ||
2670 rbd_dev->parent_overlap <= obj_request->img_offset ||
2671 ((known = obj_request_known_test(obj_request)) &&
2672 obj_request_exists_test(obj_request))) {
2674 struct rbd_device *rbd_dev;
2675 struct ceph_osd_client *osdc;
2677 rbd_dev = obj_request->img_request->rbd_dev;
2678 osdc = &rbd_dev->rbd_client->client->osdc;
2680 return rbd_obj_request_submit(osdc, obj_request);
2684 * It's a layered write. The target object might exist but
2685 * we may not know that yet. If we know it doesn't exist,
2686 * start by reading the data for the full target object from
2687 * the parent so we can use it for a copyup to the target.
2690 return rbd_img_obj_parent_read_full(obj_request);
2692 /* We don't know whether the target exists. Go find out. */
2694 return rbd_img_obj_exists_submit(obj_request);
2697 static int rbd_img_request_submit(struct rbd_img_request *img_request)
2699 struct rbd_obj_request *obj_request;
2700 struct rbd_obj_request *next_obj_request;
2702 dout("%s: img %p\n", __func__, img_request);
2703 for_each_obj_request_safe(img_request, obj_request, next_obj_request) {
2706 ret = rbd_img_obj_request_submit(obj_request);
2714 static void rbd_img_parent_read_callback(struct rbd_img_request *img_request)
2716 struct rbd_obj_request *obj_request;
2717 struct rbd_device *rbd_dev;
2722 rbd_assert(img_request_child_test(img_request));
2724 /* First get what we need from the image request and release it */
2726 obj_request = img_request->obj_request;
2727 img_xferred = img_request->xferred;
2728 img_result = img_request->result;
2729 rbd_img_request_put(img_request);
2732 * If the overlap has become 0 (most likely because the
2733 * image has been flattened) we need to re-submit the
2736 rbd_assert(obj_request);
2737 rbd_assert(obj_request->img_request);
2738 rbd_dev = obj_request->img_request->rbd_dev;
2739 if (!rbd_dev->parent_overlap) {
2740 struct ceph_osd_client *osdc;
2742 osdc = &rbd_dev->rbd_client->client->osdc;
2743 img_result = rbd_obj_request_submit(osdc, obj_request);
2748 obj_request->result = img_result;
2749 if (obj_request->result)
2753 * We need to zero anything beyond the parent overlap
2754 * boundary. Since rbd_img_obj_request_read_callback()
2755 * will zero anything beyond the end of a short read, an
2756 * easy way to do this is to pretend the data from the
2757 * parent came up short--ending at the overlap boundary.
2759 rbd_assert(obj_request->img_offset < U64_MAX - obj_request->length);
2760 obj_end = obj_request->img_offset + obj_request->length;
2761 if (obj_end > rbd_dev->parent_overlap) {
2764 if (obj_request->img_offset < rbd_dev->parent_overlap)
2765 xferred = rbd_dev->parent_overlap -
2766 obj_request->img_offset;
2768 obj_request->xferred = min(img_xferred, xferred);
2770 obj_request->xferred = img_xferred;
2773 rbd_img_obj_request_read_callback(obj_request);
2774 rbd_obj_request_complete(obj_request);
2777 static void rbd_img_parent_read(struct rbd_obj_request *obj_request)
2779 struct rbd_img_request *img_request;
2782 rbd_assert(obj_request_img_data_test(obj_request));
2783 rbd_assert(obj_request->img_request != NULL);
2784 rbd_assert(obj_request->result == (s32) -ENOENT);
2785 rbd_assert(obj_request_type_valid(obj_request->type));
2787 /* rbd_read_finish(obj_request, obj_request->length); */
2788 img_request = rbd_parent_request_create(obj_request,
2789 obj_request->img_offset,
2790 obj_request->length);
2795 if (obj_request->type == OBJ_REQUEST_BIO)
2796 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
2797 obj_request->bio_list);
2799 result = rbd_img_request_fill(img_request, OBJ_REQUEST_PAGES,
2800 obj_request->pages);
2804 img_request->callback = rbd_img_parent_read_callback;
2805 result = rbd_img_request_submit(img_request);
2812 rbd_img_request_put(img_request);
2813 obj_request->result = result;
2814 obj_request->xferred = 0;
2815 obj_request_done_set(obj_request);
2818 static int rbd_obj_notify_ack(struct rbd_device *rbd_dev, u64 notify_id)
2820 struct rbd_obj_request *obj_request;
2821 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2824 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
2825 OBJ_REQUEST_NODATA);
2830 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
2831 if (!obj_request->osd_req)
2833 obj_request->callback = rbd_obj_request_put;
2835 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK,
2837 rbd_osd_req_format_read(obj_request);
2839 ret = rbd_obj_request_submit(osdc, obj_request);
2842 rbd_obj_request_put(obj_request);
2847 static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
2849 struct rbd_device *rbd_dev = (struct rbd_device *)data;
2855 dout("%s: \"%s\" notify_id %llu opcode %u\n", __func__,
2856 rbd_dev->header_name, (unsigned long long)notify_id,
2857 (unsigned int)opcode);
2858 ret = rbd_dev_refresh(rbd_dev);
2860 rbd_warn(rbd_dev, ": header refresh error (%d)\n", ret);
2862 rbd_obj_notify_ack(rbd_dev, notify_id);
2866 * Request sync osd watch/unwatch. The value of "start" determines
2867 * whether a watch request is being initiated or torn down.
2869 static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, bool start)
2871 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2872 struct rbd_obj_request *obj_request;
2875 rbd_assert(start ^ !!rbd_dev->watch_event);
2876 rbd_assert(start ^ !!rbd_dev->watch_request);
2879 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
2880 &rbd_dev->watch_event);
2883 rbd_assert(rbd_dev->watch_event != NULL);
2887 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
2888 OBJ_REQUEST_NODATA);
2892 obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, obj_request);
2893 if (!obj_request->osd_req)
2897 ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
2899 ceph_osdc_unregister_linger_request(osdc,
2900 rbd_dev->watch_request->osd_req);
2902 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
2903 rbd_dev->watch_event->cookie, 0, start ? 1 : 0);
2904 rbd_osd_req_format_write(obj_request);
2906 ret = rbd_obj_request_submit(osdc, obj_request);
2909 ret = rbd_obj_request_wait(obj_request);
2912 ret = obj_request->result;
2917 * A watch request is set to linger, so the underlying osd
2918 * request won't go away until we unregister it. We retain
2919 * a pointer to the object request during that time (in
2920 * rbd_dev->watch_request), so we'll keep a reference to
2921 * it. We'll drop that reference (below) after we've
2925 rbd_dev->watch_request = obj_request;
2930 /* We have successfully torn down the watch request */
2932 rbd_obj_request_put(rbd_dev->watch_request);
2933 rbd_dev->watch_request = NULL;
2935 /* Cancel the event if we're tearing down, or on error */
2936 ceph_osdc_cancel_event(rbd_dev->watch_event);
2937 rbd_dev->watch_event = NULL;
2939 rbd_obj_request_put(obj_request);
2945 * Synchronous osd object method call. Returns the number of bytes
2946 * returned in the outbound buffer, or a negative error code.
2948 static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
2949 const char *object_name,
2950 const char *class_name,
2951 const char *method_name,
2952 const void *outbound,
2953 size_t outbound_size,
2955 size_t inbound_size)
2957 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2958 struct rbd_obj_request *obj_request;
2959 struct page **pages;
2964 * Method calls are ultimately read operations. The result
2965 * should placed into the inbound buffer provided. They
2966 * also supply outbound data--parameters for the object
2967 * method. Currently if this is present it will be a
2970 page_count = (u32)calc_pages_for(0, inbound_size);
2971 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2973 return PTR_ERR(pages);
2976 obj_request = rbd_obj_request_create(object_name, 0, inbound_size,
2981 obj_request->pages = pages;
2982 obj_request->page_count = page_count;
2984 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
2985 if (!obj_request->osd_req)
2988 osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL,
2989 class_name, method_name);
2990 if (outbound_size) {
2991 struct ceph_pagelist *pagelist;
2993 pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS);
2997 ceph_pagelist_init(pagelist);
2998 ceph_pagelist_append(pagelist, outbound, outbound_size);
2999 osd_req_op_cls_request_data_pagelist(obj_request->osd_req, 0,
3002 osd_req_op_cls_response_data_pages(obj_request->osd_req, 0,
3003 obj_request->pages, inbound_size,
3005 rbd_osd_req_format_read(obj_request);
3007 ret = rbd_obj_request_submit(osdc, obj_request);
3010 ret = rbd_obj_request_wait(obj_request);
3014 ret = obj_request->result;
3018 rbd_assert(obj_request->xferred < (u64)INT_MAX);
3019 ret = (int)obj_request->xferred;
3020 ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred);
3023 rbd_obj_request_put(obj_request);
3025 ceph_release_page_vector(pages, page_count);
3030 static void rbd_request_fn(struct request_queue *q)
3031 __releases(q->queue_lock) __acquires(q->queue_lock)
3033 struct rbd_device *rbd_dev = q->queuedata;
3034 bool read_only = rbd_dev->mapping.read_only;
3038 while ((rq = blk_fetch_request(q))) {
3039 bool write_request = rq_data_dir(rq) == WRITE;
3040 struct rbd_img_request *img_request;
3044 /* Ignore any non-FS requests that filter through. */
3046 if (rq->cmd_type != REQ_TYPE_FS) {
3047 dout("%s: non-fs request type %d\n", __func__,
3048 (int) rq->cmd_type);
3049 __blk_end_request_all(rq, 0);
3053 /* Ignore/skip any zero-length requests */
3055 offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT;
3056 length = (u64) blk_rq_bytes(rq);
3059 dout("%s: zero-length request\n", __func__);
3060 __blk_end_request_all(rq, 0);
3064 spin_unlock_irq(q->queue_lock);
3066 /* Disallow writes to a read-only device */
3068 if (write_request) {
3072 rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP);
3076 * Quit early if the mapped snapshot no longer
3077 * exists. It's still possible the snapshot will
3078 * have disappeared by the time our request arrives
3079 * at the osd, but there's no sense in sending it if
3082 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) {
3083 dout("request for non-existent snapshot");
3084 rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP);
3090 if (offset && length > U64_MAX - offset + 1) {
3091 rbd_warn(rbd_dev, "bad request range (%llu~%llu)\n",
3093 goto end_request; /* Shouldn't happen */
3097 if (offset + length > rbd_dev->mapping.size) {
3098 rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)\n",
3099 offset, length, rbd_dev->mapping.size);
3104 img_request = rbd_img_request_create(rbd_dev, offset, length,
3109 img_request->rq = rq;
3111 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
3114 result = rbd_img_request_submit(img_request);
3116 rbd_img_request_put(img_request);
3118 spin_lock_irq(q->queue_lock);
3120 rbd_warn(rbd_dev, "%s %llx at %llx result %d\n",
3121 write_request ? "write" : "read",
3122 length, offset, result);
3124 __blk_end_request_all(rq, result);
3130 * a queue callback. Makes sure that we don't create a bio that spans across
3131 * multiple osd objects. One exception would be with a single page bios,
3132 * which we handle later at bio_chain_clone_range()
3134 static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
3135 struct bio_vec *bvec)
3137 struct rbd_device *rbd_dev = q->queuedata;
3138 sector_t sector_offset;
3139 sector_t sectors_per_obj;
3140 sector_t obj_sector_offset;
3144 * Find how far into its rbd object the partition-relative
3145 * bio start sector is to offset relative to the enclosing
3148 sector_offset = get_start_sect(bmd->bi_bdev) + bmd->bi_sector;
3149 sectors_per_obj = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT);
3150 obj_sector_offset = sector_offset & (sectors_per_obj - 1);
3153 * Compute the number of bytes from that offset to the end
3154 * of the object. Account for what's already used by the bio.
3156 ret = (int) (sectors_per_obj - obj_sector_offset) << SECTOR_SHIFT;
3157 if (ret > bmd->bi_size)
3158 ret -= bmd->bi_size;
3163 * Don't send back more than was asked for. And if the bio
3164 * was empty, let the whole thing through because: "Note
3165 * that a block device *must* allow a single page to be
3166 * added to an empty bio."
3168 rbd_assert(bvec->bv_len <= PAGE_SIZE);
3169 if (ret > (int) bvec->bv_len || !bmd->bi_size)
3170 ret = (int) bvec->bv_len;
3175 static void rbd_free_disk(struct rbd_device *rbd_dev)
3177 struct gendisk *disk = rbd_dev->disk;
3182 rbd_dev->disk = NULL;
3183 if (disk->flags & GENHD_FL_UP) {
3186 blk_cleanup_queue(disk->queue);
3191 static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
3192 const char *object_name,
3193 u64 offset, u64 length, void *buf)
3196 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3197 struct rbd_obj_request *obj_request;
3198 struct page **pages = NULL;
3203 page_count = (u32) calc_pages_for(offset, length);
3204 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
3206 ret = PTR_ERR(pages);
3209 obj_request = rbd_obj_request_create(object_name, offset, length,
3214 obj_request->pages = pages;
3215 obj_request->page_count = page_count;
3217 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
3218 if (!obj_request->osd_req)
3221 osd_req_op_extent_init(obj_request->osd_req, 0, CEPH_OSD_OP_READ,
3222 offset, length, 0, 0);
3223 osd_req_op_extent_osd_data_pages(obj_request->osd_req, 0,
3225 obj_request->length,
3226 obj_request->offset & ~PAGE_MASK,
3228 rbd_osd_req_format_read(obj_request);
3230 ret = rbd_obj_request_submit(osdc, obj_request);
3233 ret = rbd_obj_request_wait(obj_request);
3237 ret = obj_request->result;
3241 rbd_assert(obj_request->xferred <= (u64) SIZE_MAX);
3242 size = (size_t) obj_request->xferred;
3243 ceph_copy_from_page_vector(pages, buf, 0, size);
3244 rbd_assert(size <= (size_t)INT_MAX);
3248 rbd_obj_request_put(obj_request);
3250 ceph_release_page_vector(pages, page_count);
3256 * Read the complete header for the given rbd device. On successful
3257 * return, the rbd_dev->header field will contain up-to-date
3258 * information about the image.
3260 static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
3262 struct rbd_image_header_ondisk *ondisk = NULL;
3269 * The complete header will include an array of its 64-bit
3270 * snapshot ids, followed by the names of those snapshots as
3271 * a contiguous block of NUL-terminated strings. Note that
3272 * the number of snapshots could change by the time we read
3273 * it in, in which case we re-read it.
3280 size = sizeof (*ondisk);
3281 size += snap_count * sizeof (struct rbd_image_snap_ondisk);
3283 ondisk = kmalloc(size, GFP_KERNEL);
3287 ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name,
3291 if ((size_t)ret < size) {
3293 rbd_warn(rbd_dev, "short header read (want %zd got %d)",
3297 if (!rbd_dev_ondisk_valid(ondisk)) {
3299 rbd_warn(rbd_dev, "invalid header");
3303 names_size = le64_to_cpu(ondisk->snap_names_len);
3304 want_count = snap_count;
3305 snap_count = le32_to_cpu(ondisk->snap_count);
3306 } while (snap_count != want_count);
3308 ret = rbd_header_from_disk(rbd_dev, ondisk);
3316 * Clear the rbd device's EXISTS flag if the snapshot it's mapped to
3317 * has disappeared from the (just updated) snapshot context.
3319 static void rbd_exists_validate(struct rbd_device *rbd_dev)
3323 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags))
3326 snap_id = rbd_dev->spec->snap_id;
3327 if (snap_id == CEPH_NOSNAP)
3330 if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX)
3331 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
3334 static int rbd_dev_refresh(struct rbd_device *rbd_dev)
3339 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
3340 mapping_size = rbd_dev->mapping.size;
3341 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
3342 if (rbd_dev->image_format == 1)
3343 ret = rbd_dev_v1_header_info(rbd_dev);
3345 ret = rbd_dev_v2_header_info(rbd_dev);
3347 /* If it's a mapped snapshot, validate its EXISTS flag */
3349 rbd_exists_validate(rbd_dev);
3350 mutex_unlock(&ctl_mutex);
3351 if (mapping_size != rbd_dev->mapping.size) {
3354 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
3355 dout("setting size to %llu sectors", (unsigned long long)size);
3356 set_capacity(rbd_dev->disk, size);
3357 revalidate_disk(rbd_dev->disk);
3363 static int rbd_init_disk(struct rbd_device *rbd_dev)
3365 struct gendisk *disk;
3366 struct request_queue *q;
3369 /* create gendisk info */
3370 disk = alloc_disk(RBD_MINORS_PER_MAJOR);
3374 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
3376 disk->major = rbd_dev->major;
3377 disk->first_minor = 0;
3378 disk->fops = &rbd_bd_ops;
3379 disk->private_data = rbd_dev;
3381 q = blk_init_queue(rbd_request_fn, &rbd_dev->lock);
3385 /* We use the default size, but let's be explicit about it. */
3386 blk_queue_physical_block_size(q, SECTOR_SIZE);
3388 /* set io sizes to object size */
3389 segment_size = rbd_obj_bytes(&rbd_dev->header);
3390 blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
3391 blk_queue_max_segment_size(q, segment_size);
3392 blk_queue_io_min(q, segment_size);
3393 blk_queue_io_opt(q, segment_size);
3395 blk_queue_merge_bvec(q, rbd_merge_bvec);
3398 q->queuedata = rbd_dev;
3400 rbd_dev->disk = disk;
3413 static struct rbd_device *dev_to_rbd_dev(struct device *dev)
3415 return container_of(dev, struct rbd_device, dev);
3418 static ssize_t rbd_size_show(struct device *dev,
3419 struct device_attribute *attr, char *buf)
3421 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3423 return sprintf(buf, "%llu\n",
3424 (unsigned long long)rbd_dev->mapping.size);
3428 * Note this shows the features for whatever's mapped, which is not
3429 * necessarily the base image.
3431 static ssize_t rbd_features_show(struct device *dev,
3432 struct device_attribute *attr, char *buf)
3434 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3436 return sprintf(buf, "0x%016llx\n",
3437 (unsigned long long)rbd_dev->mapping.features);
3440 static ssize_t rbd_major_show(struct device *dev,
3441 struct device_attribute *attr, char *buf)
3443 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3446 return sprintf(buf, "%d\n", rbd_dev->major);
3448 return sprintf(buf, "(none)\n");
3452 static ssize_t rbd_client_id_show(struct device *dev,
3453 struct device_attribute *attr, char *buf)
3455 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3457 return sprintf(buf, "client%lld\n",
3458 ceph_client_id(rbd_dev->rbd_client->client));
3461 static ssize_t rbd_pool_show(struct device *dev,
3462 struct device_attribute *attr, char *buf)
3464 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3466 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
3469 static ssize_t rbd_pool_id_show(struct device *dev,
3470 struct device_attribute *attr, char *buf)
3472 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3474 return sprintf(buf, "%llu\n",
3475 (unsigned long long) rbd_dev->spec->pool_id);
3478 static ssize_t rbd_name_show(struct device *dev,
3479 struct device_attribute *attr, char *buf)
3481 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3483 if (rbd_dev->spec->image_name)
3484 return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
3486 return sprintf(buf, "(unknown)\n");
3489 static ssize_t rbd_image_id_show(struct device *dev,
3490 struct device_attribute *attr, char *buf)
3492 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3494 return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
3498 * Shows the name of the currently-mapped snapshot (or
3499 * RBD_SNAP_HEAD_NAME for the base image).
3501 static ssize_t rbd_snap_show(struct device *dev,
3502 struct device_attribute *attr,
3505 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3507 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
3511 * For an rbd v2 image, shows the pool id, image id, and snapshot id
3512 * for the parent image. If there is no parent, simply shows
3513 * "(no parent image)".
3515 static ssize_t rbd_parent_show(struct device *dev,
3516 struct device_attribute *attr,
3519 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3520 struct rbd_spec *spec = rbd_dev->parent_spec;
3525 return sprintf(buf, "(no parent image)\n");
3527 count = sprintf(bufp, "pool_id %llu\npool_name %s\n",
3528 (unsigned long long) spec->pool_id, spec->pool_name);
3533 count = sprintf(bufp, "image_id %s\nimage_name %s\n", spec->image_id,
3534 spec->image_name ? spec->image_name : "(unknown)");
3539 count = sprintf(bufp, "snap_id %llu\nsnap_name %s\n",
3540 (unsigned long long) spec->snap_id, spec->snap_name);
3545 count = sprintf(bufp, "overlap %llu\n", rbd_dev->parent_overlap);
3550 return (ssize_t) (bufp - buf);
3553 static ssize_t rbd_image_refresh(struct device *dev,
3554 struct device_attribute *attr,
3558 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3561 ret = rbd_dev_refresh(rbd_dev);
3563 rbd_warn(rbd_dev, ": manual header refresh error (%d)\n", ret);
3565 return ret < 0 ? ret : size;
3568 static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
3569 static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL);
3570 static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
3571 static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
3572 static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
3573 static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL);
3574 static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
3575 static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL);
3576 static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
3577 static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
3578 static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL);
3580 static struct attribute *rbd_attrs[] = {
3581 &dev_attr_size.attr,
3582 &dev_attr_features.attr,
3583 &dev_attr_major.attr,
3584 &dev_attr_client_id.attr,
3585 &dev_attr_pool.attr,
3586 &dev_attr_pool_id.attr,
3587 &dev_attr_name.attr,
3588 &dev_attr_image_id.attr,
3589 &dev_attr_current_snap.attr,
3590 &dev_attr_parent.attr,
3591 &dev_attr_refresh.attr,
3595 static struct attribute_group rbd_attr_group = {
3599 static const struct attribute_group *rbd_attr_groups[] = {
3604 static void rbd_sysfs_dev_release(struct device *dev)
3608 static struct device_type rbd_device_type = {
3610 .groups = rbd_attr_groups,
3611 .release = rbd_sysfs_dev_release,
3614 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
3616 kref_get(&spec->kref);
3621 static void rbd_spec_free(struct kref *kref);
3622 static void rbd_spec_put(struct rbd_spec *spec)
3625 kref_put(&spec->kref, rbd_spec_free);
3628 static struct rbd_spec *rbd_spec_alloc(void)
3630 struct rbd_spec *spec;
3632 spec = kzalloc(sizeof (*spec), GFP_KERNEL);
3635 kref_init(&spec->kref);
3640 static void rbd_spec_free(struct kref *kref)
3642 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
3644 kfree(spec->pool_name);
3645 kfree(spec->image_id);
3646 kfree(spec->image_name);
3647 kfree(spec->snap_name);
3651 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
3652 struct rbd_spec *spec)
3654 struct rbd_device *rbd_dev;
3656 rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL);
3660 spin_lock_init(&rbd_dev->lock);
3662 atomic_set(&rbd_dev->parent_ref, 0);
3663 INIT_LIST_HEAD(&rbd_dev->node);
3664 init_rwsem(&rbd_dev->header_rwsem);
3666 rbd_dev->spec = spec;
3667 rbd_dev->rbd_client = rbdc;
3669 /* Initialize the layout used for all rbd requests */
3671 rbd_dev->layout.fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3672 rbd_dev->layout.fl_stripe_count = cpu_to_le32(1);
3673 rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3674 rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id);
3679 static void rbd_dev_destroy(struct rbd_device *rbd_dev)
3681 rbd_put_client(rbd_dev->rbd_client);
3682 rbd_spec_put(rbd_dev->spec);
3687 * Get the size and object order for an image snapshot, or if
3688 * snap_id is CEPH_NOSNAP, gets this information for the base
3691 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
3692 u8 *order, u64 *snap_size)
3694 __le64 snapid = cpu_to_le64(snap_id);
3699 } __attribute__ ((packed)) size_buf = { 0 };
3701 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3703 &snapid, sizeof (snapid),
3704 &size_buf, sizeof (size_buf));
3705 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3708 if (ret < sizeof (size_buf))
3712 *order = size_buf.order;
3713 *snap_size = le64_to_cpu(size_buf.size);
3715 dout(" snap_id 0x%016llx order = %u, snap_size = %llu\n",
3716 (unsigned long long)snap_id, (unsigned int)*order,
3717 (unsigned long long)*snap_size);
3722 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
3724 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
3725 &rbd_dev->header.obj_order,
3726 &rbd_dev->header.image_size);
3729 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
3735 reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL);
3739 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3740 "rbd", "get_object_prefix", NULL, 0,
3741 reply_buf, RBD_OBJ_PREFIX_LEN_MAX);
3742 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3747 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
3748 p + ret, NULL, GFP_NOIO);
3751 if (IS_ERR(rbd_dev->header.object_prefix)) {
3752 ret = PTR_ERR(rbd_dev->header.object_prefix);
3753 rbd_dev->header.object_prefix = NULL;
3755 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix);
3763 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
3766 __le64 snapid = cpu_to_le64(snap_id);
3770 } __attribute__ ((packed)) features_buf = { 0 };
3774 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3775 "rbd", "get_features",
3776 &snapid, sizeof (snapid),
3777 &features_buf, sizeof (features_buf));
3778 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3781 if (ret < sizeof (features_buf))
3784 incompat = le64_to_cpu(features_buf.incompat);
3785 if (incompat & ~RBD_FEATURES_SUPPORTED)
3788 *snap_features = le64_to_cpu(features_buf.features);
3790 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
3791 (unsigned long long)snap_id,
3792 (unsigned long long)*snap_features,
3793 (unsigned long long)le64_to_cpu(features_buf.incompat));
3798 static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
3800 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
3801 &rbd_dev->header.features);
3804 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
3806 struct rbd_spec *parent_spec;
3808 void *reply_buf = NULL;
3817 parent_spec = rbd_spec_alloc();
3821 size = sizeof (__le64) + /* pool_id */
3822 sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */
3823 sizeof (__le64) + /* snap_id */
3824 sizeof (__le64); /* overlap */
3825 reply_buf = kmalloc(size, GFP_KERNEL);
3831 snapid = cpu_to_le64(CEPH_NOSNAP);
3832 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3833 "rbd", "get_parent",
3834 &snapid, sizeof (snapid),
3836 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3841 end = reply_buf + ret;
3843 ceph_decode_64_safe(&p, end, pool_id, out_err);
3844 if (pool_id == CEPH_NOPOOL) {
3846 * Either the parent never existed, or we have
3847 * record of it but the image got flattened so it no
3848 * longer has a parent. When the parent of a
3849 * layered image disappears we immediately set the
3850 * overlap to 0. The effect of this is that all new
3851 * requests will be treated as if the image had no
3854 if (rbd_dev->parent_overlap) {
3855 rbd_dev->parent_overlap = 0;
3857 rbd_dev_parent_put(rbd_dev);
3858 pr_info("%s: clone image has been flattened\n",
3859 rbd_dev->disk->disk_name);
3862 goto out; /* No parent? No problem. */
3865 /* The ceph file layout needs to fit pool id in 32 bits */
3868 if (pool_id > (u64)U32_MAX) {
3869 rbd_warn(NULL, "parent pool id too large (%llu > %u)\n",
3870 (unsigned long long)pool_id, U32_MAX);
3873 parent_spec->pool_id = pool_id;
3875 image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
3876 if (IS_ERR(image_id)) {
3877 ret = PTR_ERR(image_id);
3880 parent_spec->image_id = image_id;
3881 ceph_decode_64_safe(&p, end, parent_spec->snap_id, out_err);
3882 ceph_decode_64_safe(&p, end, overlap, out_err);
3885 rbd_spec_put(rbd_dev->parent_spec);
3886 rbd_dev->parent_spec = parent_spec;
3887 parent_spec = NULL; /* rbd_dev now owns this */
3888 rbd_dev->parent_overlap = overlap;
3890 rbd_warn(rbd_dev, "ignoring parent of clone with overlap 0\n");
3896 rbd_spec_put(parent_spec);
3901 static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
3905 __le64 stripe_count;
3906 } __attribute__ ((packed)) striping_info_buf = { 0 };
3907 size_t size = sizeof (striping_info_buf);
3914 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3915 "rbd", "get_stripe_unit_count", NULL, 0,
3916 (char *)&striping_info_buf, size);
3917 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3924 * We don't actually support the "fancy striping" feature
3925 * (STRIPINGV2) yet, but if the striping sizes are the
3926 * defaults the behavior is the same as before. So find
3927 * out, and only fail if the image has non-default values.
3930 obj_size = (u64)1 << rbd_dev->header.obj_order;
3931 p = &striping_info_buf;
3932 stripe_unit = ceph_decode_64(&p);
3933 if (stripe_unit != obj_size) {
3934 rbd_warn(rbd_dev, "unsupported stripe unit "
3935 "(got %llu want %llu)",
3936 stripe_unit, obj_size);
3939 stripe_count = ceph_decode_64(&p);
3940 if (stripe_count != 1) {
3941 rbd_warn(rbd_dev, "unsupported stripe count "
3942 "(got %llu want 1)", stripe_count);
3945 rbd_dev->header.stripe_unit = stripe_unit;
3946 rbd_dev->header.stripe_count = stripe_count;
3951 static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
3953 size_t image_id_size;
3958 void *reply_buf = NULL;
3960 char *image_name = NULL;
3963 rbd_assert(!rbd_dev->spec->image_name);
3965 len = strlen(rbd_dev->spec->image_id);
3966 image_id_size = sizeof (__le32) + len;
3967 image_id = kmalloc(image_id_size, GFP_KERNEL);
3972 end = image_id + image_id_size;
3973 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
3975 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
3976 reply_buf = kmalloc(size, GFP_KERNEL);
3980 ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY,
3981 "rbd", "dir_get_name",
3982 image_id, image_id_size,
3987 end = reply_buf + ret;
3989 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
3990 if (IS_ERR(image_name))
3993 dout("%s: name is %s len is %zd\n", __func__, image_name, len);
4001 static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4003 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
4004 const char *snap_name;
4007 /* Skip over names until we find the one we are looking for */
4009 snap_name = rbd_dev->header.snap_names;
4010 while (which < snapc->num_snaps) {
4011 if (!strcmp(name, snap_name))
4012 return snapc->snaps[which];
4013 snap_name += strlen(snap_name) + 1;
4019 static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4021 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
4026 for (which = 0; !found && which < snapc->num_snaps; which++) {
4027 const char *snap_name;
4029 snap_id = snapc->snaps[which];
4030 snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
4031 if (IS_ERR(snap_name))
4033 found = !strcmp(name, snap_name);
4036 return found ? snap_id : CEPH_NOSNAP;
4040 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
4041 * no snapshot by that name is found, or if an error occurs.
4043 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4045 if (rbd_dev->image_format == 1)
4046 return rbd_v1_snap_id_by_name(rbd_dev, name);
4048 return rbd_v2_snap_id_by_name(rbd_dev, name);
4052 * When an rbd image has a parent image, it is identified by the
4053 * pool, image, and snapshot ids (not names). This function fills
4054 * in the names for those ids. (It's OK if we can't figure out the
4055 * name for an image id, but the pool and snapshot ids should always
4056 * exist and have names.) All names in an rbd spec are dynamically
4059 * When an image being mapped (not a parent) is probed, we have the
4060 * pool name and pool id, image name and image id, and the snapshot
4061 * name. The only thing we're missing is the snapshot id.
4063 static int rbd_dev_spec_update(struct rbd_device *rbd_dev)
4065 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4066 struct rbd_spec *spec = rbd_dev->spec;
4067 const char *pool_name;
4068 const char *image_name;
4069 const char *snap_name;
4073 * An image being mapped will have the pool name (etc.), but
4074 * we need to look up the snapshot id.
4076 if (spec->pool_name) {
4077 if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
4080 snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
4081 if (snap_id == CEPH_NOSNAP)
4083 spec->snap_id = snap_id;
4085 spec->snap_id = CEPH_NOSNAP;
4091 /* Get the pool name; we have to make our own copy of this */
4093 pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
4095 rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
4098 pool_name = kstrdup(pool_name, GFP_KERNEL);
4102 /* Fetch the image name; tolerate failure here */
4104 image_name = rbd_dev_image_name(rbd_dev);
4106 rbd_warn(rbd_dev, "unable to get image name");
4108 /* Look up the snapshot name, and make a copy */
4110 snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
4116 spec->pool_name = pool_name;
4117 spec->image_name = image_name;
4118 spec->snap_name = snap_name;
4128 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
4137 struct ceph_snap_context *snapc;
4141 * We'll need room for the seq value (maximum snapshot id),
4142 * snapshot count, and array of that many snapshot ids.
4143 * For now we have a fixed upper limit on the number we're
4144 * prepared to receive.
4146 size = sizeof (__le64) + sizeof (__le32) +
4147 RBD_MAX_SNAP_COUNT * sizeof (__le64);
4148 reply_buf = kzalloc(size, GFP_KERNEL);
4152 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4153 "rbd", "get_snapcontext", NULL, 0,
4155 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4160 end = reply_buf + ret;
4162 ceph_decode_64_safe(&p, end, seq, out);
4163 ceph_decode_32_safe(&p, end, snap_count, out);
4166 * Make sure the reported number of snapshot ids wouldn't go
4167 * beyond the end of our buffer. But before checking that,
4168 * make sure the computed size of the snapshot context we
4169 * allocate is representable in a size_t.
4171 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
4176 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
4180 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
4186 for (i = 0; i < snap_count; i++)
4187 snapc->snaps[i] = ceph_decode_64(&p);
4189 ceph_put_snap_context(rbd_dev->header.snapc);
4190 rbd_dev->header.snapc = snapc;
4192 dout(" snap context seq = %llu, snap_count = %u\n",
4193 (unsigned long long)seq, (unsigned int)snap_count);
4200 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
4211 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
4212 reply_buf = kmalloc(size, GFP_KERNEL);
4214 return ERR_PTR(-ENOMEM);
4216 snapid = cpu_to_le64(snap_id);
4217 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4218 "rbd", "get_snapshot_name",
4219 &snapid, sizeof (snapid),
4221 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4223 snap_name = ERR_PTR(ret);
4228 end = reply_buf + ret;
4229 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
4230 if (IS_ERR(snap_name))
4233 dout(" snap_id 0x%016llx snap_name = %s\n",
4234 (unsigned long long)snap_id, snap_name);
4241 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
4243 bool first_time = rbd_dev->header.object_prefix == NULL;
4246 down_write(&rbd_dev->header_rwsem);
4248 ret = rbd_dev_v2_image_size(rbd_dev);
4253 ret = rbd_dev_v2_header_onetime(rbd_dev);
4259 * If the image supports layering, get the parent info. We
4260 * need to probe the first time regardless. Thereafter we
4261 * only need to if there's a parent, to see if it has
4262 * disappeared due to the mapped image getting flattened.
4264 if (rbd_dev->header.features & RBD_FEATURE_LAYERING &&
4265 (first_time || rbd_dev->parent_spec)) {
4268 ret = rbd_dev_v2_parent_info(rbd_dev);
4273 * Print a warning if this is the initial probe and
4274 * the image has a parent. Don't print it if the
4275 * image now being probed is itself a parent. We
4276 * can tell at this point because we won't know its
4277 * pool name yet (just its pool id).
4279 warn = rbd_dev->parent_spec && rbd_dev->spec->pool_name;
4280 if (first_time && warn)
4281 rbd_warn(rbd_dev, "WARNING: kernel layering "
4282 "is EXPERIMENTAL!");
4285 if (rbd_dev->spec->snap_id == CEPH_NOSNAP)
4286 if (rbd_dev->mapping.size != rbd_dev->header.image_size)
4287 rbd_dev->mapping.size = rbd_dev->header.image_size;
4289 ret = rbd_dev_v2_snap_context(rbd_dev);
4290 dout("rbd_dev_v2_snap_context returned %d\n", ret);
4292 up_write(&rbd_dev->header_rwsem);
4297 static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
4302 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
4304 dev = &rbd_dev->dev;
4305 dev->bus = &rbd_bus_type;
4306 dev->type = &rbd_device_type;
4307 dev->parent = &rbd_root_dev;
4308 dev->release = rbd_dev_device_release;
4309 dev_set_name(dev, "%d", rbd_dev->dev_id);
4310 ret = device_register(dev);
4312 mutex_unlock(&ctl_mutex);
4317 static void rbd_bus_del_dev(struct rbd_device *rbd_dev)
4319 device_unregister(&rbd_dev->dev);
4322 static atomic64_t rbd_dev_id_max = ATOMIC64_INIT(0);
4325 * Get a unique rbd identifier for the given new rbd_dev, and add
4326 * the rbd_dev to the global list. The minimum rbd id is 1.
4328 static void rbd_dev_id_get(struct rbd_device *rbd_dev)
4330 rbd_dev->dev_id = atomic64_inc_return(&rbd_dev_id_max);
4332 spin_lock(&rbd_dev_list_lock);
4333 list_add_tail(&rbd_dev->node, &rbd_dev_list);
4334 spin_unlock(&rbd_dev_list_lock);
4335 dout("rbd_dev %p given dev id %llu\n", rbd_dev,
4336 (unsigned long long) rbd_dev->dev_id);
4340 * Remove an rbd_dev from the global list, and record that its
4341 * identifier is no longer in use.
4343 static void rbd_dev_id_put(struct rbd_device *rbd_dev)
4345 struct list_head *tmp;
4346 int rbd_id = rbd_dev->dev_id;
4349 rbd_assert(rbd_id > 0);
4351 dout("rbd_dev %p released dev id %llu\n", rbd_dev,
4352 (unsigned long long) rbd_dev->dev_id);
4353 spin_lock(&rbd_dev_list_lock);
4354 list_del_init(&rbd_dev->node);
4357 * If the id being "put" is not the current maximum, there
4358 * is nothing special we need to do.
4360 if (rbd_id != atomic64_read(&rbd_dev_id_max)) {
4361 spin_unlock(&rbd_dev_list_lock);
4366 * We need to update the current maximum id. Search the
4367 * list to find out what it is. We're more likely to find
4368 * the maximum at the end, so search the list backward.
4371 list_for_each_prev(tmp, &rbd_dev_list) {
4372 struct rbd_device *rbd_dev;
4374 rbd_dev = list_entry(tmp, struct rbd_device, node);
4375 if (rbd_dev->dev_id > max_id)
4376 max_id = rbd_dev->dev_id;
4378 spin_unlock(&rbd_dev_list_lock);
4381 * The max id could have been updated by rbd_dev_id_get(), in
4382 * which case it now accurately reflects the new maximum.
4383 * Be careful not to overwrite the maximum value in that
4386 atomic64_cmpxchg(&rbd_dev_id_max, rbd_id, max_id);
4387 dout(" max dev id has been reset\n");
4391 * Skips over white space at *buf, and updates *buf to point to the
4392 * first found non-space character (if any). Returns the length of
4393 * the token (string of non-white space characters) found. Note
4394 * that *buf must be terminated with '\0'.
4396 static inline size_t next_token(const char **buf)
4399 * These are the characters that produce nonzero for
4400 * isspace() in the "C" and "POSIX" locales.
4402 const char *spaces = " \f\n\r\t\v";
4404 *buf += strspn(*buf, spaces); /* Find start of token */
4406 return strcspn(*buf, spaces); /* Return token length */
4410 * Finds the next token in *buf, and if the provided token buffer is
4411 * big enough, copies the found token into it. The result, if
4412 * copied, is guaranteed to be terminated with '\0'. Note that *buf
4413 * must be terminated with '\0' on entry.
4415 * Returns the length of the token found (not including the '\0').
4416 * Return value will be 0 if no token is found, and it will be >=
4417 * token_size if the token would not fit.
4419 * The *buf pointer will be updated to point beyond the end of the
4420 * found token. Note that this occurs even if the token buffer is
4421 * too small to hold it.
4423 static inline size_t copy_token(const char **buf,
4429 len = next_token(buf);
4430 if (len < token_size) {
4431 memcpy(token, *buf, len);
4432 *(token + len) = '\0';
4440 * Finds the next token in *buf, dynamically allocates a buffer big
4441 * enough to hold a copy of it, and copies the token into the new
4442 * buffer. The copy is guaranteed to be terminated with '\0'. Note
4443 * that a duplicate buffer is created even for a zero-length token.
4445 * Returns a pointer to the newly-allocated duplicate, or a null
4446 * pointer if memory for the duplicate was not available. If
4447 * the lenp argument is a non-null pointer, the length of the token
4448 * (not including the '\0') is returned in *lenp.
4450 * If successful, the *buf pointer will be updated to point beyond
4451 * the end of the found token.
4453 * Note: uses GFP_KERNEL for allocation.
4455 static inline char *dup_token(const char **buf, size_t *lenp)
4460 len = next_token(buf);
4461 dup = kmemdup(*buf, len + 1, GFP_KERNEL);
4464 *(dup + len) = '\0';
4474 * Parse the options provided for an "rbd add" (i.e., rbd image
4475 * mapping) request. These arrive via a write to /sys/bus/rbd/add,
4476 * and the data written is passed here via a NUL-terminated buffer.
4477 * Returns 0 if successful or an error code otherwise.
4479 * The information extracted from these options is recorded in
4480 * the other parameters which return dynamically-allocated
4483 * The address of a pointer that will refer to a ceph options
4484 * structure. Caller must release the returned pointer using
4485 * ceph_destroy_options() when it is no longer needed.
4487 * Address of an rbd options pointer. Fully initialized by
4488 * this function; caller must release with kfree().
4490 * Address of an rbd image specification pointer. Fully
4491 * initialized by this function based on parsed options.
4492 * Caller must release with rbd_spec_put().
4494 * The options passed take this form:
4495 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
4498 * A comma-separated list of one or more monitor addresses.
4499 * A monitor address is an ip address, optionally followed
4500 * by a port number (separated by a colon).
4501 * I.e.: ip1[:port1][,ip2[:port2]...]
4503 * A comma-separated list of ceph and/or rbd options.
4505 * The name of the rados pool containing the rbd image.
4507 * The name of the image in that pool to map.
4509 * An optional snapshot id. If provided, the mapping will
4510 * present data from the image at the time that snapshot was
4511 * created. The image head is used if no snapshot id is
4512 * provided. Snapshot mappings are always read-only.
4514 static int rbd_add_parse_args(const char *buf,
4515 struct ceph_options **ceph_opts,
4516 struct rbd_options **opts,
4517 struct rbd_spec **rbd_spec)
4521 const char *mon_addrs;
4523 size_t mon_addrs_size;
4524 struct rbd_spec *spec = NULL;
4525 struct rbd_options *rbd_opts = NULL;
4526 struct ceph_options *copts;
4529 /* The first four tokens are required */
4531 len = next_token(&buf);
4533 rbd_warn(NULL, "no monitor address(es) provided");
4537 mon_addrs_size = len + 1;
4541 options = dup_token(&buf, NULL);
4545 rbd_warn(NULL, "no options provided");
4549 spec = rbd_spec_alloc();
4553 spec->pool_name = dup_token(&buf, NULL);
4554 if (!spec->pool_name)
4556 if (!*spec->pool_name) {
4557 rbd_warn(NULL, "no pool name provided");
4561 spec->image_name = dup_token(&buf, NULL);
4562 if (!spec->image_name)
4564 if (!*spec->image_name) {
4565 rbd_warn(NULL, "no image name provided");
4570 * Snapshot name is optional; default is to use "-"
4571 * (indicating the head/no snapshot).
4573 len = next_token(&buf);
4575 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
4576 len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
4577 } else if (len > RBD_MAX_SNAP_NAME_LEN) {
4578 ret = -ENAMETOOLONG;
4581 snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
4584 *(snap_name + len) = '\0';
4585 spec->snap_name = snap_name;
4587 /* Initialize all rbd options to the defaults */
4589 rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL);
4593 rbd_opts->read_only = RBD_READ_ONLY_DEFAULT;
4595 copts = ceph_parse_options(options, mon_addrs,
4596 mon_addrs + mon_addrs_size - 1,
4597 parse_rbd_opts_token, rbd_opts);
4598 if (IS_ERR(copts)) {
4599 ret = PTR_ERR(copts);
4620 * An rbd format 2 image has a unique identifier, distinct from the
4621 * name given to it by the user. Internally, that identifier is
4622 * what's used to specify the names of objects related to the image.
4624 * A special "rbd id" object is used to map an rbd image name to its
4625 * id. If that object doesn't exist, then there is no v2 rbd image
4626 * with the supplied name.
4628 * This function will record the given rbd_dev's image_id field if
4629 * it can be determined, and in that case will return 0. If any
4630 * errors occur a negative errno will be returned and the rbd_dev's
4631 * image_id field will be unchanged (and should be NULL).
4633 static int rbd_dev_image_id(struct rbd_device *rbd_dev)
4642 * When probing a parent image, the image id is already
4643 * known (and the image name likely is not). There's no
4644 * need to fetch the image id again in this case. We
4645 * do still need to set the image format though.
4647 if (rbd_dev->spec->image_id) {
4648 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;
4654 * First, see if the format 2 image id file exists, and if
4655 * so, get the image's persistent id from it.
4657 size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name);
4658 object_name = kmalloc(size, GFP_NOIO);
4661 sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name);
4662 dout("rbd id object name is %s\n", object_name);
4664 /* Response will be an encoded string, which includes a length */
4666 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
4667 response = kzalloc(size, GFP_NOIO);
4673 /* If it doesn't exist we'll assume it's a format 1 image */
4675 ret = rbd_obj_method_sync(rbd_dev, object_name,
4676 "rbd", "get_id", NULL, 0,
4677 response, RBD_IMAGE_ID_LEN_MAX);
4678 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4679 if (ret == -ENOENT) {
4680 image_id = kstrdup("", GFP_KERNEL);
4681 ret = image_id ? 0 : -ENOMEM;
4683 rbd_dev->image_format = 1;
4684 } else if (ret > sizeof (__le32)) {
4687 image_id = ceph_extract_encoded_string(&p, p + ret,
4689 ret = IS_ERR(image_id) ? PTR_ERR(image_id) : 0;
4691 rbd_dev->image_format = 2;
4697 rbd_dev->spec->image_id = image_id;
4698 dout("image_id is %s\n", image_id);
4708 * Undo whatever state changes are made by v1 or v2 header info
4711 static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
4713 struct rbd_image_header *header;
4715 /* Drop parent reference unless it's already been done (or none) */
4717 if (rbd_dev->parent_overlap)
4718 rbd_dev_parent_put(rbd_dev);
4720 /* Free dynamic fields from the header, then zero it out */
4722 header = &rbd_dev->header;
4723 ceph_put_snap_context(header->snapc);
4724 kfree(header->snap_sizes);
4725 kfree(header->snap_names);
4726 kfree(header->object_prefix);
4727 memset(header, 0, sizeof (*header));
4730 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev)
4734 ret = rbd_dev_v2_object_prefix(rbd_dev);
4739 * Get the and check features for the image. Currently the
4740 * features are assumed to never change.
4742 ret = rbd_dev_v2_features(rbd_dev);
4746 /* If the image supports fancy striping, get its parameters */
4748 if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
4749 ret = rbd_dev_v2_striping_info(rbd_dev);
4753 /* No support for crypto and compression type format 2 images */
4757 rbd_dev->header.features = 0;
4758 kfree(rbd_dev->header.object_prefix);
4759 rbd_dev->header.object_prefix = NULL;
4764 static int rbd_dev_probe_parent(struct rbd_device *rbd_dev)
4766 struct rbd_device *parent = NULL;
4767 struct rbd_spec *parent_spec;
4768 struct rbd_client *rbdc;
4771 if (!rbd_dev->parent_spec)
4774 * We need to pass a reference to the client and the parent
4775 * spec when creating the parent rbd_dev. Images related by
4776 * parent/child relationships always share both.
4778 parent_spec = rbd_spec_get(rbd_dev->parent_spec);
4779 rbdc = __rbd_get_client(rbd_dev->rbd_client);
4782 parent = rbd_dev_create(rbdc, parent_spec);
4786 ret = rbd_dev_image_probe(parent, false);
4789 rbd_dev->parent = parent;
4790 atomic_set(&rbd_dev->parent_ref, 1);
4795 rbd_dev_unparent(rbd_dev);
4796 kfree(rbd_dev->header_name);
4797 rbd_dev_destroy(parent);
4799 rbd_put_client(rbdc);
4800 rbd_spec_put(parent_spec);
4806 static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
4810 /* generate unique id: find highest unique id, add one */
4811 rbd_dev_id_get(rbd_dev);
4813 /* Fill in the device name, now that we have its id. */
4814 BUILD_BUG_ON(DEV_NAME_LEN
4815 < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
4816 sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id);
4818 /* Get our block major device number. */
4820 ret = register_blkdev(0, rbd_dev->name);
4823 rbd_dev->major = ret;
4825 /* Set up the blkdev mapping. */
4827 ret = rbd_init_disk(rbd_dev);
4829 goto err_out_blkdev;
4831 ret = rbd_dev_mapping_set(rbd_dev);
4834 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
4836 ret = rbd_bus_add_dev(rbd_dev);
4838 goto err_out_mapping;
4840 /* Everything's ready. Announce the disk to the world. */
4842 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
4843 add_disk(rbd_dev->disk);
4845 pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name,
4846 (unsigned long long) rbd_dev->mapping.size);
4851 rbd_dev_mapping_clear(rbd_dev);
4853 rbd_free_disk(rbd_dev);
4855 unregister_blkdev(rbd_dev->major, rbd_dev->name);
4857 rbd_dev_id_put(rbd_dev);
4858 rbd_dev_mapping_clear(rbd_dev);
4863 static int rbd_dev_header_name(struct rbd_device *rbd_dev)
4865 struct rbd_spec *spec = rbd_dev->spec;
4868 /* Record the header object name for this rbd image. */
4870 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
4872 if (rbd_dev->image_format == 1)
4873 size = strlen(spec->image_name) + sizeof (RBD_SUFFIX);
4875 size = sizeof (RBD_HEADER_PREFIX) + strlen(spec->image_id);
4877 rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
4878 if (!rbd_dev->header_name)
4881 if (rbd_dev->image_format == 1)
4882 sprintf(rbd_dev->header_name, "%s%s",
4883 spec->image_name, RBD_SUFFIX);
4885 sprintf(rbd_dev->header_name, "%s%s",
4886 RBD_HEADER_PREFIX, spec->image_id);
4890 static void rbd_dev_image_release(struct rbd_device *rbd_dev)
4892 rbd_dev_unprobe(rbd_dev);
4893 kfree(rbd_dev->header_name);
4894 rbd_dev->header_name = NULL;
4895 rbd_dev->image_format = 0;
4896 kfree(rbd_dev->spec->image_id);
4897 rbd_dev->spec->image_id = NULL;
4899 rbd_dev_destroy(rbd_dev);
4903 * Probe for the existence of the header object for the given rbd
4904 * device. If this image is the one being mapped (i.e., not a
4905 * parent), initiate a watch on its header object before using that
4906 * object to get detailed information about the rbd image.
4908 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping)
4914 * Get the id from the image id object. Unless there's an
4915 * error, rbd_dev->spec->image_id will be filled in with
4916 * a dynamically-allocated string, and rbd_dev->image_format
4917 * will be set to either 1 or 2.
4919 ret = rbd_dev_image_id(rbd_dev);
4922 rbd_assert(rbd_dev->spec->image_id);
4923 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
4925 ret = rbd_dev_header_name(rbd_dev);
4927 goto err_out_format;
4930 ret = rbd_dev_header_watch_sync(rbd_dev, true);
4932 goto out_header_name;
4935 if (rbd_dev->image_format == 1)
4936 ret = rbd_dev_v1_header_info(rbd_dev);
4938 ret = rbd_dev_v2_header_info(rbd_dev);
4942 ret = rbd_dev_spec_update(rbd_dev);
4946 ret = rbd_dev_probe_parent(rbd_dev);
4950 dout("discovered format %u image, header name is %s\n",
4951 rbd_dev->image_format, rbd_dev->header_name);
4955 rbd_dev_unprobe(rbd_dev);
4958 tmp = rbd_dev_header_watch_sync(rbd_dev, false);
4960 rbd_warn(rbd_dev, "unable to tear down "
4961 "watch request (%d)\n", tmp);
4964 kfree(rbd_dev->header_name);
4965 rbd_dev->header_name = NULL;
4967 rbd_dev->image_format = 0;
4968 kfree(rbd_dev->spec->image_id);
4969 rbd_dev->spec->image_id = NULL;
4971 dout("probe failed, returning %d\n", ret);
4976 static ssize_t rbd_add(struct bus_type *bus,
4980 struct rbd_device *rbd_dev = NULL;
4981 struct ceph_options *ceph_opts = NULL;
4982 struct rbd_options *rbd_opts = NULL;
4983 struct rbd_spec *spec = NULL;
4984 struct rbd_client *rbdc;
4985 struct ceph_osd_client *osdc;
4989 if (!try_module_get(THIS_MODULE))
4992 /* parse add command */
4993 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
4995 goto err_out_module;
4996 read_only = rbd_opts->read_only;
4998 rbd_opts = NULL; /* done with this */
5000 rbdc = rbd_get_client(ceph_opts);
5007 osdc = &rbdc->client->osdc;
5008 rc = ceph_pg_poolid_by_name(osdc->osdmap, spec->pool_name);
5010 goto err_out_client;
5011 spec->pool_id = (u64)rc;
5013 /* The ceph file layout needs to fit pool id in 32 bits */
5015 if (spec->pool_id > (u64)U32_MAX) {
5016 rbd_warn(NULL, "pool id too large (%llu > %u)\n",
5017 (unsigned long long)spec->pool_id, U32_MAX);
5019 goto err_out_client;
5022 rbd_dev = rbd_dev_create(rbdc, spec);
5024 goto err_out_client;
5025 rbdc = NULL; /* rbd_dev now owns this */
5026 spec = NULL; /* rbd_dev now owns this */
5028 rc = rbd_dev_image_probe(rbd_dev, true);
5030 goto err_out_rbd_dev;
5032 /* If we are mapping a snapshot it must be marked read-only */
5034 if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
5036 rbd_dev->mapping.read_only = read_only;
5038 rc = rbd_dev_device_setup(rbd_dev);
5040 rbd_dev_image_release(rbd_dev);
5041 goto err_out_module;
5047 rbd_dev_destroy(rbd_dev);
5049 rbd_put_client(rbdc);
5053 module_put(THIS_MODULE);
5055 dout("Error adding device %s\n", buf);
5060 static struct rbd_device *__rbd_get_dev(unsigned long dev_id)
5062 struct list_head *tmp;
5063 struct rbd_device *rbd_dev;
5065 spin_lock(&rbd_dev_list_lock);
5066 list_for_each(tmp, &rbd_dev_list) {
5067 rbd_dev = list_entry(tmp, struct rbd_device, node);
5068 if (rbd_dev->dev_id == dev_id) {
5069 spin_unlock(&rbd_dev_list_lock);
5073 spin_unlock(&rbd_dev_list_lock);
5077 static void rbd_dev_device_release(struct device *dev)
5079 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5081 rbd_free_disk(rbd_dev);
5082 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
5083 rbd_dev_mapping_clear(rbd_dev);
5084 unregister_blkdev(rbd_dev->major, rbd_dev->name);
5086 rbd_dev_id_put(rbd_dev);
5087 rbd_dev_mapping_clear(rbd_dev);
5090 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
5092 while (rbd_dev->parent) {
5093 struct rbd_device *first = rbd_dev;
5094 struct rbd_device *second = first->parent;
5095 struct rbd_device *third;
5098 * Follow to the parent with no grandparent and
5101 while (second && (third = second->parent)) {
5106 rbd_dev_image_release(second);
5107 first->parent = NULL;
5108 first->parent_overlap = 0;
5110 rbd_assert(first->parent_spec);
5111 rbd_spec_put(first->parent_spec);
5112 first->parent_spec = NULL;
5116 static ssize_t rbd_remove(struct bus_type *bus,
5120 struct rbd_device *rbd_dev = NULL;
5125 ret = strict_strtoul(buf, 10, &ul);
5129 /* convert to int; abort if we lost anything in the conversion */
5130 target_id = (int) ul;
5131 if (target_id != ul)
5134 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
5136 rbd_dev = __rbd_get_dev(target_id);
5142 spin_lock_irq(&rbd_dev->lock);
5143 if (rbd_dev->open_count)
5146 set_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags);
5147 spin_unlock_irq(&rbd_dev->lock);
5150 rbd_bus_del_dev(rbd_dev);
5151 ret = rbd_dev_header_watch_sync(rbd_dev, false);
5153 rbd_warn(rbd_dev, "failed to cancel watch event (%d)\n", ret);
5154 rbd_dev_image_release(rbd_dev);
5155 module_put(THIS_MODULE);
5158 mutex_unlock(&ctl_mutex);
5164 * create control files in sysfs
5167 static int rbd_sysfs_init(void)
5171 ret = device_register(&rbd_root_dev);
5175 ret = bus_register(&rbd_bus_type);
5177 device_unregister(&rbd_root_dev);
5182 static void rbd_sysfs_cleanup(void)
5184 bus_unregister(&rbd_bus_type);
5185 device_unregister(&rbd_root_dev);
5188 static int rbd_slab_init(void)
5190 rbd_assert(!rbd_img_request_cache);
5191 rbd_img_request_cache = kmem_cache_create("rbd_img_request",
5192 sizeof (struct rbd_img_request),
5193 __alignof__(struct rbd_img_request),
5195 if (!rbd_img_request_cache)
5198 rbd_assert(!rbd_obj_request_cache);
5199 rbd_obj_request_cache = kmem_cache_create("rbd_obj_request",
5200 sizeof (struct rbd_obj_request),
5201 __alignof__(struct rbd_obj_request),
5203 if (!rbd_obj_request_cache)
5206 rbd_assert(!rbd_segment_name_cache);
5207 rbd_segment_name_cache = kmem_cache_create("rbd_segment_name",
5208 MAX_OBJ_NAME_SIZE + 1, 1, 0, NULL);
5209 if (rbd_segment_name_cache)
5212 if (rbd_obj_request_cache) {
5213 kmem_cache_destroy(rbd_obj_request_cache);
5214 rbd_obj_request_cache = NULL;
5217 kmem_cache_destroy(rbd_img_request_cache);
5218 rbd_img_request_cache = NULL;
5223 static void rbd_slab_exit(void)
5225 rbd_assert(rbd_segment_name_cache);
5226 kmem_cache_destroy(rbd_segment_name_cache);
5227 rbd_segment_name_cache = NULL;
5229 rbd_assert(rbd_obj_request_cache);
5230 kmem_cache_destroy(rbd_obj_request_cache);
5231 rbd_obj_request_cache = NULL;
5233 rbd_assert(rbd_img_request_cache);
5234 kmem_cache_destroy(rbd_img_request_cache);
5235 rbd_img_request_cache = NULL;
5238 static int __init rbd_init(void)
5242 if (!libceph_compatible(NULL)) {
5243 rbd_warn(NULL, "libceph incompatibility (quitting)");
5247 rc = rbd_slab_init();
5250 rc = rbd_sysfs_init();
5254 pr_info("loaded " RBD_DRV_NAME_LONG "\n");
5259 static void __exit rbd_exit(void)
5261 rbd_sysfs_cleanup();
5265 module_init(rbd_init);
5266 module_exit(rbd_exit);
5268 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
5269 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
5270 MODULE_DESCRIPTION("rados block device");
5272 /* following authorship retained from original osdblk.c */
5273 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
5275 MODULE_LICENSE("GPL");