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 void 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);
515 static const struct block_device_operations rbd_bd_ops = {
516 .owner = THIS_MODULE,
518 .release = rbd_release,
522 * Initialize an rbd client instance. Success or not, this function
523 * consumes ceph_opts.
525 static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
527 struct rbd_client *rbdc;
530 dout("%s:\n", __func__);
531 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
535 kref_init(&rbdc->kref);
536 INIT_LIST_HEAD(&rbdc->node);
538 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
540 rbdc->client = ceph_create_client(ceph_opts, rbdc, 0, 0);
541 if (IS_ERR(rbdc->client))
543 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
545 ret = ceph_open_session(rbdc->client);
549 spin_lock(&rbd_client_list_lock);
550 list_add_tail(&rbdc->node, &rbd_client_list);
551 spin_unlock(&rbd_client_list_lock);
553 mutex_unlock(&ctl_mutex);
554 dout("%s: rbdc %p\n", __func__, rbdc);
559 ceph_destroy_client(rbdc->client);
561 mutex_unlock(&ctl_mutex);
565 ceph_destroy_options(ceph_opts);
566 dout("%s: error %d\n", __func__, ret);
571 static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
573 kref_get(&rbdc->kref);
579 * Find a ceph client with specific addr and configuration. If
580 * found, bump its reference count.
582 static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
584 struct rbd_client *client_node;
587 if (ceph_opts->flags & CEPH_OPT_NOSHARE)
590 spin_lock(&rbd_client_list_lock);
591 list_for_each_entry(client_node, &rbd_client_list, node) {
592 if (!ceph_compare_options(ceph_opts, client_node->client)) {
593 __rbd_get_client(client_node);
599 spin_unlock(&rbd_client_list_lock);
601 return found ? client_node : NULL;
611 /* string args above */
614 /* Boolean args above */
618 static match_table_t rbd_opts_tokens = {
620 /* string args above */
621 {Opt_read_only, "read_only"},
622 {Opt_read_only, "ro"}, /* Alternate spelling */
623 {Opt_read_write, "read_write"},
624 {Opt_read_write, "rw"}, /* Alternate spelling */
625 /* Boolean args above */
633 #define RBD_READ_ONLY_DEFAULT false
635 static int parse_rbd_opts_token(char *c, void *private)
637 struct rbd_options *rbd_opts = private;
638 substring_t argstr[MAX_OPT_ARGS];
639 int token, intval, ret;
641 token = match_token(c, rbd_opts_tokens, argstr);
645 if (token < Opt_last_int) {
646 ret = match_int(&argstr[0], &intval);
648 pr_err("bad mount option arg (not int) "
652 dout("got int token %d val %d\n", token, intval);
653 } else if (token > Opt_last_int && token < Opt_last_string) {
654 dout("got string token %d val %s\n", token,
656 } else if (token > Opt_last_string && token < Opt_last_bool) {
657 dout("got Boolean token %d\n", token);
659 dout("got token %d\n", token);
664 rbd_opts->read_only = true;
667 rbd_opts->read_only = false;
677 * Get a ceph client with specific addr and configuration, if one does
678 * not exist create it. Either way, ceph_opts is consumed by this
681 static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
683 struct rbd_client *rbdc;
685 rbdc = rbd_client_find(ceph_opts);
686 if (rbdc) /* using an existing client */
687 ceph_destroy_options(ceph_opts);
689 rbdc = rbd_client_create(ceph_opts);
695 * Destroy ceph client
697 * Caller must hold rbd_client_list_lock.
699 static void rbd_client_release(struct kref *kref)
701 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
703 dout("%s: rbdc %p\n", __func__, rbdc);
704 spin_lock(&rbd_client_list_lock);
705 list_del(&rbdc->node);
706 spin_unlock(&rbd_client_list_lock);
708 ceph_destroy_client(rbdc->client);
713 * Drop reference to ceph client node. If it's not referenced anymore, release
716 static void rbd_put_client(struct rbd_client *rbdc)
719 kref_put(&rbdc->kref, rbd_client_release);
722 static bool rbd_image_format_valid(u32 image_format)
724 return image_format == 1 || image_format == 2;
727 static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
732 /* The header has to start with the magic rbd header text */
733 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
736 /* The bio layer requires at least sector-sized I/O */
738 if (ondisk->options.order < SECTOR_SHIFT)
741 /* If we use u64 in a few spots we may be able to loosen this */
743 if (ondisk->options.order > 8 * sizeof (int) - 1)
747 * The size of a snapshot header has to fit in a size_t, and
748 * that limits the number of snapshots.
750 snap_count = le32_to_cpu(ondisk->snap_count);
751 size = SIZE_MAX - sizeof (struct ceph_snap_context);
752 if (snap_count > size / sizeof (__le64))
756 * Not only that, but the size of the entire the snapshot
757 * header must also be representable in a size_t.
759 size -= snap_count * sizeof (__le64);
760 if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
767 * Fill an rbd image header with information from the given format 1
770 static int rbd_header_from_disk(struct rbd_device *rbd_dev,
771 struct rbd_image_header_ondisk *ondisk)
773 struct rbd_image_header *header = &rbd_dev->header;
774 bool first_time = header->object_prefix == NULL;
775 struct ceph_snap_context *snapc;
776 char *object_prefix = NULL;
777 char *snap_names = NULL;
778 u64 *snap_sizes = NULL;
784 /* Allocate this now to avoid having to handle failure below */
789 len = strnlen(ondisk->object_prefix,
790 sizeof (ondisk->object_prefix));
791 object_prefix = kmalloc(len + 1, GFP_KERNEL);
794 memcpy(object_prefix, ondisk->object_prefix, len);
795 object_prefix[len] = '\0';
798 /* Allocate the snapshot context and fill it in */
800 snap_count = le32_to_cpu(ondisk->snap_count);
801 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
804 snapc->seq = le64_to_cpu(ondisk->snap_seq);
806 struct rbd_image_snap_ondisk *snaps;
807 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);
809 /* We'll keep a copy of the snapshot names... */
811 if (snap_names_len > (u64)SIZE_MAX)
813 snap_names = kmalloc(snap_names_len, GFP_KERNEL);
817 /* ...as well as the array of their sizes. */
819 size = snap_count * sizeof (*header->snap_sizes);
820 snap_sizes = kmalloc(size, GFP_KERNEL);
825 * Copy the names, and fill in each snapshot's id
828 * Note that rbd_dev_v1_header_info() guarantees the
829 * ondisk buffer we're working with has
830 * snap_names_len bytes beyond the end of the
831 * snapshot id array, this memcpy() is safe.
833 memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len);
834 snaps = ondisk->snaps;
835 for (i = 0; i < snap_count; i++) {
836 snapc->snaps[i] = le64_to_cpu(snaps[i].id);
837 snap_sizes[i] = le64_to_cpu(snaps[i].image_size);
841 /* We won't fail any more, fill in the header */
843 down_write(&rbd_dev->header_rwsem);
845 header->object_prefix = object_prefix;
846 header->obj_order = ondisk->options.order;
847 header->crypt_type = ondisk->options.crypt_type;
848 header->comp_type = ondisk->options.comp_type;
849 /* The rest aren't used for format 1 images */
850 header->stripe_unit = 0;
851 header->stripe_count = 0;
852 header->features = 0;
854 ceph_put_snap_context(header->snapc);
855 kfree(header->snap_names);
856 kfree(header->snap_sizes);
859 /* The remaining fields always get updated (when we refresh) */
861 header->image_size = le64_to_cpu(ondisk->image_size);
862 header->snapc = snapc;
863 header->snap_names = snap_names;
864 header->snap_sizes = snap_sizes;
866 /* Make sure mapping size is consistent with header info */
868 if (rbd_dev->spec->snap_id == CEPH_NOSNAP || first_time)
869 if (rbd_dev->mapping.size != header->image_size)
870 rbd_dev->mapping.size = header->image_size;
872 up_write(&rbd_dev->header_rwsem);
880 ceph_put_snap_context(snapc);
881 kfree(object_prefix);
886 static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
888 const char *snap_name;
890 rbd_assert(which < rbd_dev->header.snapc->num_snaps);
892 /* Skip over names until we find the one we are looking for */
894 snap_name = rbd_dev->header.snap_names;
896 snap_name += strlen(snap_name) + 1;
898 return kstrdup(snap_name, GFP_KERNEL);
902 * Snapshot id comparison function for use with qsort()/bsearch().
903 * Note that result is for snapshots in *descending* order.
905 static int snapid_compare_reverse(const void *s1, const void *s2)
907 u64 snap_id1 = *(u64 *)s1;
908 u64 snap_id2 = *(u64 *)s2;
910 if (snap_id1 < snap_id2)
912 return snap_id1 == snap_id2 ? 0 : -1;
916 * Search a snapshot context to see if the given snapshot id is
919 * Returns the position of the snapshot id in the array if it's found,
920 * or BAD_SNAP_INDEX otherwise.
922 * Note: The snapshot array is in kept sorted (by the osd) in
923 * reverse order, highest snapshot id first.
925 static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id)
927 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
930 found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps,
931 sizeof (snap_id), snapid_compare_reverse);
933 return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX;
936 static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
941 which = rbd_dev_snap_index(rbd_dev, snap_id);
942 if (which == BAD_SNAP_INDEX)
945 return _rbd_dev_v1_snap_name(rbd_dev, which);
948 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
950 if (snap_id == CEPH_NOSNAP)
951 return RBD_SNAP_HEAD_NAME;
953 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
954 if (rbd_dev->image_format == 1)
955 return rbd_dev_v1_snap_name(rbd_dev, snap_id);
957 return rbd_dev_v2_snap_name(rbd_dev, snap_id);
960 static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
963 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
964 if (snap_id == CEPH_NOSNAP) {
965 *snap_size = rbd_dev->header.image_size;
966 } else if (rbd_dev->image_format == 1) {
969 which = rbd_dev_snap_index(rbd_dev, snap_id);
970 if (which == BAD_SNAP_INDEX)
973 *snap_size = rbd_dev->header.snap_sizes[which];
978 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
987 static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
990 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
991 if (snap_id == CEPH_NOSNAP) {
992 *snap_features = rbd_dev->header.features;
993 } else if (rbd_dev->image_format == 1) {
994 *snap_features = 0; /* No features for format 1 */
999 ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features);
1003 *snap_features = features;
1008 static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
1010 u64 snap_id = rbd_dev->spec->snap_id;
1015 ret = rbd_snap_size(rbd_dev, snap_id, &size);
1018 ret = rbd_snap_features(rbd_dev, snap_id, &features);
1022 rbd_dev->mapping.size = size;
1023 rbd_dev->mapping.features = features;
1028 static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
1030 rbd_dev->mapping.size = 0;
1031 rbd_dev->mapping.features = 0;
1034 static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset)
1040 name = kmem_cache_alloc(rbd_segment_name_cache, GFP_NOIO);
1043 segment = offset >> rbd_dev->header.obj_order;
1044 ret = snprintf(name, MAX_OBJ_NAME_SIZE + 1, "%s.%012llx",
1045 rbd_dev->header.object_prefix, segment);
1046 if (ret < 0 || ret > MAX_OBJ_NAME_SIZE) {
1047 pr_err("error formatting segment name for #%llu (%d)\n",
1056 static void rbd_segment_name_free(const char *name)
1058 /* The explicit cast here is needed to drop the const qualifier */
1060 kmem_cache_free(rbd_segment_name_cache, (void *)name);
1063 static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset)
1065 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1067 return offset & (segment_size - 1);
1070 static u64 rbd_segment_length(struct rbd_device *rbd_dev,
1071 u64 offset, u64 length)
1073 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1075 offset &= segment_size - 1;
1077 rbd_assert(length <= U64_MAX - offset);
1078 if (offset + length > segment_size)
1079 length = segment_size - offset;
1085 * returns the size of an object in the image
1087 static u64 rbd_obj_bytes(struct rbd_image_header *header)
1089 return 1 << header->obj_order;
1096 static void bio_chain_put(struct bio *chain)
1102 chain = chain->bi_next;
1108 * zeros a bio chain, starting at specific offset
1110 static void zero_bio_chain(struct bio *chain, int start_ofs)
1113 unsigned long flags;
1119 bio_for_each_segment(bv, chain, i) {
1120 if (pos + bv->bv_len > start_ofs) {
1121 int remainder = max(start_ofs - pos, 0);
1122 buf = bvec_kmap_irq(bv, &flags);
1123 memset(buf + remainder, 0,
1124 bv->bv_len - remainder);
1125 bvec_kunmap_irq(buf, &flags);
1130 chain = chain->bi_next;
1135 * similar to zero_bio_chain(), zeros data defined by a page array,
1136 * starting at the given byte offset from the start of the array and
1137 * continuing up to the given end offset. The pages array is
1138 * assumed to be big enough to hold all bytes up to the end.
1140 static void zero_pages(struct page **pages, u64 offset, u64 end)
1142 struct page **page = &pages[offset >> PAGE_SHIFT];
1144 rbd_assert(end > offset);
1145 rbd_assert(end - offset <= (u64)SIZE_MAX);
1146 while (offset < end) {
1149 unsigned long flags;
1152 page_offset = (size_t)(offset & ~PAGE_MASK);
1153 length = min(PAGE_SIZE - page_offset, (size_t)(end - offset));
1154 local_irq_save(flags);
1155 kaddr = kmap_atomic(*page);
1156 memset(kaddr + page_offset, 0, length);
1157 kunmap_atomic(kaddr);
1158 local_irq_restore(flags);
1166 * Clone a portion of a bio, starting at the given byte offset
1167 * and continuing for the number of bytes indicated.
1169 static struct bio *bio_clone_range(struct bio *bio_src,
1170 unsigned int offset,
1178 unsigned short end_idx;
1179 unsigned short vcnt;
1182 /* Handle the easy case for the caller */
1184 if (!offset && len == bio_src->bi_size)
1185 return bio_clone(bio_src, gfpmask);
1187 if (WARN_ON_ONCE(!len))
1189 if (WARN_ON_ONCE(len > bio_src->bi_size))
1191 if (WARN_ON_ONCE(offset > bio_src->bi_size - len))
1194 /* Find first affected segment... */
1197 bio_for_each_segment(bv, bio_src, idx) {
1198 if (resid < bv->bv_len)
1200 resid -= bv->bv_len;
1204 /* ...and the last affected segment */
1207 __bio_for_each_segment(bv, bio_src, end_idx, idx) {
1208 if (resid <= bv->bv_len)
1210 resid -= bv->bv_len;
1212 vcnt = end_idx - idx + 1;
1214 /* Build the clone */
1216 bio = bio_alloc(gfpmask, (unsigned int) vcnt);
1218 return NULL; /* ENOMEM */
1220 bio->bi_bdev = bio_src->bi_bdev;
1221 bio->bi_sector = bio_src->bi_sector + (offset >> SECTOR_SHIFT);
1222 bio->bi_rw = bio_src->bi_rw;
1223 bio->bi_flags |= 1 << BIO_CLONED;
1226 * Copy over our part of the bio_vec, then update the first
1227 * and last (or only) entries.
1229 memcpy(&bio->bi_io_vec[0], &bio_src->bi_io_vec[idx],
1230 vcnt * sizeof (struct bio_vec));
1231 bio->bi_io_vec[0].bv_offset += voff;
1233 bio->bi_io_vec[0].bv_len -= voff;
1234 bio->bi_io_vec[vcnt - 1].bv_len = resid;
1236 bio->bi_io_vec[0].bv_len = len;
1239 bio->bi_vcnt = vcnt;
1247 * Clone a portion of a bio chain, starting at the given byte offset
1248 * into the first bio in the source chain and continuing for the
1249 * number of bytes indicated. The result is another bio chain of
1250 * exactly the given length, or a null pointer on error.
1252 * The bio_src and offset parameters are both in-out. On entry they
1253 * refer to the first source bio and the offset into that bio where
1254 * the start of data to be cloned is located.
1256 * On return, bio_src is updated to refer to the bio in the source
1257 * chain that contains first un-cloned byte, and *offset will
1258 * contain the offset of that byte within that bio.
1260 static struct bio *bio_chain_clone_range(struct bio **bio_src,
1261 unsigned int *offset,
1265 struct bio *bi = *bio_src;
1266 unsigned int off = *offset;
1267 struct bio *chain = NULL;
1270 /* Build up a chain of clone bios up to the limit */
1272 if (!bi || off >= bi->bi_size || !len)
1273 return NULL; /* Nothing to clone */
1277 unsigned int bi_size;
1281 rbd_warn(NULL, "bio_chain exhausted with %u left", len);
1282 goto out_err; /* EINVAL; ran out of bio's */
1284 bi_size = min_t(unsigned int, bi->bi_size - off, len);
1285 bio = bio_clone_range(bi, off, bi_size, gfpmask);
1287 goto out_err; /* ENOMEM */
1290 end = &bio->bi_next;
1293 if (off == bi->bi_size) {
1304 bio_chain_put(chain);
1310 * The default/initial value for all object request flags is 0. For
1311 * each flag, once its value is set to 1 it is never reset to 0
1314 static void obj_request_img_data_set(struct rbd_obj_request *obj_request)
1316 if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) {
1317 struct rbd_device *rbd_dev;
1319 rbd_dev = obj_request->img_request->rbd_dev;
1320 rbd_warn(rbd_dev, "obj_request %p already marked img_data\n",
1325 static bool obj_request_img_data_test(struct rbd_obj_request *obj_request)
1328 return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0;
1331 static void obj_request_done_set(struct rbd_obj_request *obj_request)
1333 if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) {
1334 struct rbd_device *rbd_dev = NULL;
1336 if (obj_request_img_data_test(obj_request))
1337 rbd_dev = obj_request->img_request->rbd_dev;
1338 rbd_warn(rbd_dev, "obj_request %p already marked done\n",
1343 static bool obj_request_done_test(struct rbd_obj_request *obj_request)
1346 return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0;
1350 * This sets the KNOWN flag after (possibly) setting the EXISTS
1351 * flag. The latter is set based on the "exists" value provided.
1353 * Note that for our purposes once an object exists it never goes
1354 * away again. It's possible that the response from two existence
1355 * checks are separated by the creation of the target object, and
1356 * the first ("doesn't exist") response arrives *after* the second
1357 * ("does exist"). In that case we ignore the second one.
1359 static void obj_request_existence_set(struct rbd_obj_request *obj_request,
1363 set_bit(OBJ_REQ_EXISTS, &obj_request->flags);
1364 set_bit(OBJ_REQ_KNOWN, &obj_request->flags);
1368 static bool obj_request_known_test(struct rbd_obj_request *obj_request)
1371 return test_bit(OBJ_REQ_KNOWN, &obj_request->flags) != 0;
1374 static bool obj_request_exists_test(struct rbd_obj_request *obj_request)
1377 return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0;
1380 static void rbd_obj_request_get(struct rbd_obj_request *obj_request)
1382 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1383 atomic_read(&obj_request->kref.refcount));
1384 kref_get(&obj_request->kref);
1387 static void rbd_obj_request_destroy(struct kref *kref);
1388 static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
1390 rbd_assert(obj_request != NULL);
1391 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1392 atomic_read(&obj_request->kref.refcount));
1393 kref_put(&obj_request->kref, rbd_obj_request_destroy);
1396 static bool img_request_child_test(struct rbd_img_request *img_request);
1397 static void rbd_parent_request_destroy(struct kref *kref);
1398 static void rbd_img_request_destroy(struct kref *kref);
1399 static void rbd_img_request_put(struct rbd_img_request *img_request)
1401 rbd_assert(img_request != NULL);
1402 dout("%s: img %p (was %d)\n", __func__, img_request,
1403 atomic_read(&img_request->kref.refcount));
1404 if (img_request_child_test(img_request))
1405 kref_put(&img_request->kref, rbd_parent_request_destroy);
1407 kref_put(&img_request->kref, rbd_img_request_destroy);
1410 static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
1411 struct rbd_obj_request *obj_request)
1413 rbd_assert(obj_request->img_request == NULL);
1415 /* Image request now owns object's original reference */
1416 obj_request->img_request = img_request;
1417 obj_request->which = img_request->obj_request_count;
1418 rbd_assert(!obj_request_img_data_test(obj_request));
1419 obj_request_img_data_set(obj_request);
1420 rbd_assert(obj_request->which != BAD_WHICH);
1421 img_request->obj_request_count++;
1422 list_add_tail(&obj_request->links, &img_request->obj_requests);
1423 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1424 obj_request->which);
1427 static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
1428 struct rbd_obj_request *obj_request)
1430 rbd_assert(obj_request->which != BAD_WHICH);
1432 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1433 obj_request->which);
1434 list_del(&obj_request->links);
1435 rbd_assert(img_request->obj_request_count > 0);
1436 img_request->obj_request_count--;
1437 rbd_assert(obj_request->which == img_request->obj_request_count);
1438 obj_request->which = BAD_WHICH;
1439 rbd_assert(obj_request_img_data_test(obj_request));
1440 rbd_assert(obj_request->img_request == img_request);
1441 obj_request->img_request = NULL;
1442 obj_request->callback = NULL;
1443 rbd_obj_request_put(obj_request);
1446 static bool obj_request_type_valid(enum obj_request_type type)
1449 case OBJ_REQUEST_NODATA:
1450 case OBJ_REQUEST_BIO:
1451 case OBJ_REQUEST_PAGES:
1458 static int rbd_obj_request_submit(struct ceph_osd_client *osdc,
1459 struct rbd_obj_request *obj_request)
1461 dout("%s: osdc %p obj %p\n", __func__, osdc, obj_request);
1463 return ceph_osdc_start_request(osdc, obj_request->osd_req, false);
1466 static void rbd_img_request_complete(struct rbd_img_request *img_request)
1469 dout("%s: img %p\n", __func__, img_request);
1472 * If no error occurred, compute the aggregate transfer
1473 * count for the image request. We could instead use
1474 * atomic64_cmpxchg() to update it as each object request
1475 * completes; not clear which way is better off hand.
1477 if (!img_request->result) {
1478 struct rbd_obj_request *obj_request;
1481 for_each_obj_request(img_request, obj_request)
1482 xferred += obj_request->xferred;
1483 img_request->xferred = xferred;
1486 if (img_request->callback)
1487 img_request->callback(img_request);
1489 rbd_img_request_put(img_request);
1492 /* Caller is responsible for rbd_obj_request_destroy(obj_request) */
1494 static int rbd_obj_request_wait(struct rbd_obj_request *obj_request)
1496 dout("%s: obj %p\n", __func__, obj_request);
1498 return wait_for_completion_interruptible(&obj_request->completion);
1502 * The default/initial value for all image request flags is 0. Each
1503 * is conditionally set to 1 at image request initialization time
1504 * and currently never change thereafter.
1506 static void img_request_write_set(struct rbd_img_request *img_request)
1508 set_bit(IMG_REQ_WRITE, &img_request->flags);
1512 static bool img_request_write_test(struct rbd_img_request *img_request)
1515 return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0;
1518 static void img_request_child_set(struct rbd_img_request *img_request)
1520 set_bit(IMG_REQ_CHILD, &img_request->flags);
1524 static void img_request_child_clear(struct rbd_img_request *img_request)
1526 clear_bit(IMG_REQ_CHILD, &img_request->flags);
1530 static bool img_request_child_test(struct rbd_img_request *img_request)
1533 return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0;
1536 static void img_request_layered_set(struct rbd_img_request *img_request)
1538 set_bit(IMG_REQ_LAYERED, &img_request->flags);
1542 static void img_request_layered_clear(struct rbd_img_request *img_request)
1544 clear_bit(IMG_REQ_LAYERED, &img_request->flags);
1548 static bool img_request_layered_test(struct rbd_img_request *img_request)
1551 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
1555 rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
1557 u64 xferred = obj_request->xferred;
1558 u64 length = obj_request->length;
1560 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1561 obj_request, obj_request->img_request, obj_request->result,
1564 * ENOENT means a hole in the image. We zero-fill the
1565 * entire length of the request. A short read also implies
1566 * zero-fill to the end of the request. Either way we
1567 * update the xferred count to indicate the whole request
1570 rbd_assert(obj_request->type != OBJ_REQUEST_NODATA);
1571 if (obj_request->result == -ENOENT) {
1572 if (obj_request->type == OBJ_REQUEST_BIO)
1573 zero_bio_chain(obj_request->bio_list, 0);
1575 zero_pages(obj_request->pages, 0, length);
1576 obj_request->result = 0;
1577 obj_request->xferred = length;
1578 } else if (xferred < length && !obj_request->result) {
1579 if (obj_request->type == OBJ_REQUEST_BIO)
1580 zero_bio_chain(obj_request->bio_list, xferred);
1582 zero_pages(obj_request->pages, xferred, length);
1583 obj_request->xferred = length;
1585 obj_request_done_set(obj_request);
1588 static void rbd_obj_request_complete(struct rbd_obj_request *obj_request)
1590 dout("%s: obj %p cb %p\n", __func__, obj_request,
1591 obj_request->callback);
1592 if (obj_request->callback)
1593 obj_request->callback(obj_request);
1595 complete_all(&obj_request->completion);
1598 static void rbd_osd_trivial_callback(struct rbd_obj_request *obj_request)
1600 dout("%s: obj %p\n", __func__, obj_request);
1601 obj_request_done_set(obj_request);
1604 static void rbd_osd_read_callback(struct rbd_obj_request *obj_request)
1606 struct rbd_img_request *img_request = NULL;
1607 struct rbd_device *rbd_dev = NULL;
1608 bool layered = false;
1610 if (obj_request_img_data_test(obj_request)) {
1611 img_request = obj_request->img_request;
1612 layered = img_request && img_request_layered_test(img_request);
1613 rbd_dev = img_request->rbd_dev;
1616 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1617 obj_request, img_request, obj_request->result,
1618 obj_request->xferred, obj_request->length);
1619 if (layered && obj_request->result == -ENOENT &&
1620 obj_request->img_offset < rbd_dev->parent_overlap)
1621 rbd_img_parent_read(obj_request);
1622 else if (img_request)
1623 rbd_img_obj_request_read_callback(obj_request);
1625 obj_request_done_set(obj_request);
1628 static void rbd_osd_write_callback(struct rbd_obj_request *obj_request)
1630 dout("%s: obj %p result %d %llu\n", __func__, obj_request,
1631 obj_request->result, obj_request->length);
1633 * There is no such thing as a successful short write. Set
1634 * it to our originally-requested length.
1636 obj_request->xferred = obj_request->length;
1637 obj_request_done_set(obj_request);
1641 * For a simple stat call there's nothing to do. We'll do more if
1642 * this is part of a write sequence for a layered image.
1644 static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request)
1646 dout("%s: obj %p\n", __func__, obj_request);
1647 obj_request_done_set(obj_request);
1650 static void rbd_osd_req_callback(struct ceph_osd_request *osd_req,
1651 struct ceph_msg *msg)
1653 struct rbd_obj_request *obj_request = osd_req->r_priv;
1656 dout("%s: osd_req %p msg %p\n", __func__, osd_req, msg);
1657 rbd_assert(osd_req == obj_request->osd_req);
1658 if (obj_request_img_data_test(obj_request)) {
1659 rbd_assert(obj_request->img_request);
1660 rbd_assert(obj_request->which != BAD_WHICH);
1662 rbd_assert(obj_request->which == BAD_WHICH);
1665 if (osd_req->r_result < 0)
1666 obj_request->result = osd_req->r_result;
1668 BUG_ON(osd_req->r_num_ops > 2);
1671 * We support a 64-bit length, but ultimately it has to be
1672 * passed to blk_end_request(), which takes an unsigned int.
1674 obj_request->xferred = osd_req->r_reply_op_len[0];
1675 rbd_assert(obj_request->xferred < (u64)UINT_MAX);
1676 opcode = osd_req->r_ops[0].op;
1678 case CEPH_OSD_OP_READ:
1679 rbd_osd_read_callback(obj_request);
1681 case CEPH_OSD_OP_WRITE:
1682 rbd_osd_write_callback(obj_request);
1684 case CEPH_OSD_OP_STAT:
1685 rbd_osd_stat_callback(obj_request);
1687 case CEPH_OSD_OP_CALL:
1688 case CEPH_OSD_OP_NOTIFY_ACK:
1689 case CEPH_OSD_OP_WATCH:
1690 rbd_osd_trivial_callback(obj_request);
1693 rbd_warn(NULL, "%s: unsupported op %hu\n",
1694 obj_request->object_name, (unsigned short) opcode);
1698 if (obj_request_done_test(obj_request))
1699 rbd_obj_request_complete(obj_request);
1702 static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request)
1704 struct rbd_img_request *img_request = obj_request->img_request;
1705 struct ceph_osd_request *osd_req = obj_request->osd_req;
1708 rbd_assert(osd_req != NULL);
1710 snap_id = img_request ? img_request->snap_id : CEPH_NOSNAP;
1711 ceph_osdc_build_request(osd_req, obj_request->offset,
1712 NULL, snap_id, NULL);
1715 static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request)
1717 struct rbd_img_request *img_request = obj_request->img_request;
1718 struct ceph_osd_request *osd_req = obj_request->osd_req;
1719 struct ceph_snap_context *snapc;
1720 struct timespec mtime = CURRENT_TIME;
1722 rbd_assert(osd_req != NULL);
1724 snapc = img_request ? img_request->snapc : NULL;
1725 ceph_osdc_build_request(osd_req, obj_request->offset,
1726 snapc, CEPH_NOSNAP, &mtime);
1729 static struct ceph_osd_request *rbd_osd_req_create(
1730 struct rbd_device *rbd_dev,
1732 struct rbd_obj_request *obj_request)
1734 struct ceph_snap_context *snapc = NULL;
1735 struct ceph_osd_client *osdc;
1736 struct ceph_osd_request *osd_req;
1738 if (obj_request_img_data_test(obj_request)) {
1739 struct rbd_img_request *img_request = obj_request->img_request;
1741 rbd_assert(write_request ==
1742 img_request_write_test(img_request));
1744 snapc = img_request->snapc;
1747 /* Allocate and initialize the request, for the single op */
1749 osdc = &rbd_dev->rbd_client->client->osdc;
1750 osd_req = ceph_osdc_alloc_request(osdc, snapc, 1, false, GFP_ATOMIC);
1752 return NULL; /* ENOMEM */
1755 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1757 osd_req->r_flags = CEPH_OSD_FLAG_READ;
1759 osd_req->r_callback = rbd_osd_req_callback;
1760 osd_req->r_priv = obj_request;
1762 osd_req->r_oid_len = strlen(obj_request->object_name);
1763 rbd_assert(osd_req->r_oid_len < sizeof (osd_req->r_oid));
1764 memcpy(osd_req->r_oid, obj_request->object_name, osd_req->r_oid_len);
1766 osd_req->r_file_layout = rbd_dev->layout; /* struct */
1772 * Create a copyup osd request based on the information in the
1773 * object request supplied. A copyup request has two osd ops,
1774 * a copyup method call, and a "normal" write request.
1776 static struct ceph_osd_request *
1777 rbd_osd_req_create_copyup(struct rbd_obj_request *obj_request)
1779 struct rbd_img_request *img_request;
1780 struct ceph_snap_context *snapc;
1781 struct rbd_device *rbd_dev;
1782 struct ceph_osd_client *osdc;
1783 struct ceph_osd_request *osd_req;
1785 rbd_assert(obj_request_img_data_test(obj_request));
1786 img_request = obj_request->img_request;
1787 rbd_assert(img_request);
1788 rbd_assert(img_request_write_test(img_request));
1790 /* Allocate and initialize the request, for the two ops */
1792 snapc = img_request->snapc;
1793 rbd_dev = img_request->rbd_dev;
1794 osdc = &rbd_dev->rbd_client->client->osdc;
1795 osd_req = ceph_osdc_alloc_request(osdc, snapc, 2, false, GFP_ATOMIC);
1797 return NULL; /* ENOMEM */
1799 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1800 osd_req->r_callback = rbd_osd_req_callback;
1801 osd_req->r_priv = obj_request;
1803 osd_req->r_oid_len = strlen(obj_request->object_name);
1804 rbd_assert(osd_req->r_oid_len < sizeof (osd_req->r_oid));
1805 memcpy(osd_req->r_oid, obj_request->object_name, osd_req->r_oid_len);
1807 osd_req->r_file_layout = rbd_dev->layout; /* struct */
1813 static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req)
1815 ceph_osdc_put_request(osd_req);
1818 /* object_name is assumed to be a non-null pointer and NUL-terminated */
1820 static struct rbd_obj_request *rbd_obj_request_create(const char *object_name,
1821 u64 offset, u64 length,
1822 enum obj_request_type type)
1824 struct rbd_obj_request *obj_request;
1828 rbd_assert(obj_request_type_valid(type));
1830 size = strlen(object_name) + 1;
1831 name = kmalloc(size, GFP_KERNEL);
1835 obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_KERNEL);
1841 obj_request->object_name = memcpy(name, object_name, size);
1842 obj_request->offset = offset;
1843 obj_request->length = length;
1844 obj_request->flags = 0;
1845 obj_request->which = BAD_WHICH;
1846 obj_request->type = type;
1847 INIT_LIST_HEAD(&obj_request->links);
1848 init_completion(&obj_request->completion);
1849 kref_init(&obj_request->kref);
1851 dout("%s: \"%s\" %llu/%llu %d -> obj %p\n", __func__, object_name,
1852 offset, length, (int)type, obj_request);
1857 static void rbd_obj_request_destroy(struct kref *kref)
1859 struct rbd_obj_request *obj_request;
1861 obj_request = container_of(kref, struct rbd_obj_request, kref);
1863 dout("%s: obj %p\n", __func__, obj_request);
1865 rbd_assert(obj_request->img_request == NULL);
1866 rbd_assert(obj_request->which == BAD_WHICH);
1868 if (obj_request->osd_req)
1869 rbd_osd_req_destroy(obj_request->osd_req);
1871 rbd_assert(obj_request_type_valid(obj_request->type));
1872 switch (obj_request->type) {
1873 case OBJ_REQUEST_NODATA:
1874 break; /* Nothing to do */
1875 case OBJ_REQUEST_BIO:
1876 if (obj_request->bio_list)
1877 bio_chain_put(obj_request->bio_list);
1879 case OBJ_REQUEST_PAGES:
1880 if (obj_request->pages)
1881 ceph_release_page_vector(obj_request->pages,
1882 obj_request->page_count);
1886 kfree(obj_request->object_name);
1887 obj_request->object_name = NULL;
1888 kmem_cache_free(rbd_obj_request_cache, obj_request);
1891 /* It's OK to call this for a device with no parent */
1893 static void rbd_spec_put(struct rbd_spec *spec);
1894 static void rbd_dev_unparent(struct rbd_device *rbd_dev)
1896 rbd_dev_remove_parent(rbd_dev);
1897 rbd_spec_put(rbd_dev->parent_spec);
1898 rbd_dev->parent_spec = NULL;
1899 rbd_dev->parent_overlap = 0;
1903 * Parent image reference counting is used to determine when an
1904 * image's parent fields can be safely torn down--after there are no
1905 * more in-flight requests to the parent image. When the last
1906 * reference is dropped, cleaning them up is safe.
1908 static void rbd_dev_parent_put(struct rbd_device *rbd_dev)
1912 if (!rbd_dev->parent_spec)
1915 counter = atomic_dec_return_safe(&rbd_dev->parent_ref);
1919 /* Last reference; clean up parent data structures */
1922 rbd_dev_unparent(rbd_dev);
1924 rbd_warn(rbd_dev, "parent reference underflow\n");
1928 * If an image has a non-zero parent overlap, get a reference to its
1931 * We must get the reference before checking for the overlap to
1932 * coordinate properly with zeroing the parent overlap in
1933 * rbd_dev_v2_parent_info() when an image gets flattened. We
1934 * drop it again if there is no overlap.
1936 * Returns true if the rbd device has a parent with a non-zero
1937 * overlap and a reference for it was successfully taken, or
1940 static bool rbd_dev_parent_get(struct rbd_device *rbd_dev)
1944 if (!rbd_dev->parent_spec)
1947 counter = atomic_inc_return_safe(&rbd_dev->parent_ref);
1948 if (counter > 0 && rbd_dev->parent_overlap)
1951 /* Image was flattened, but parent is not yet torn down */
1954 rbd_warn(rbd_dev, "parent reference overflow\n");
1960 * Caller is responsible for filling in the list of object requests
1961 * that comprises the image request, and the Linux request pointer
1962 * (if there is one).
1964 static struct rbd_img_request *rbd_img_request_create(
1965 struct rbd_device *rbd_dev,
1966 u64 offset, u64 length,
1969 struct rbd_img_request *img_request;
1971 img_request = kmem_cache_alloc(rbd_img_request_cache, GFP_ATOMIC);
1975 if (write_request) {
1976 down_read(&rbd_dev->header_rwsem);
1977 ceph_get_snap_context(rbd_dev->header.snapc);
1978 up_read(&rbd_dev->header_rwsem);
1981 img_request->rq = NULL;
1982 img_request->rbd_dev = rbd_dev;
1983 img_request->offset = offset;
1984 img_request->length = length;
1985 img_request->flags = 0;
1986 if (write_request) {
1987 img_request_write_set(img_request);
1988 img_request->snapc = rbd_dev->header.snapc;
1990 img_request->snap_id = rbd_dev->spec->snap_id;
1992 if (rbd_dev_parent_get(rbd_dev))
1993 img_request_layered_set(img_request);
1994 spin_lock_init(&img_request->completion_lock);
1995 img_request->next_completion = 0;
1996 img_request->callback = NULL;
1997 img_request->result = 0;
1998 img_request->obj_request_count = 0;
1999 INIT_LIST_HEAD(&img_request->obj_requests);
2000 kref_init(&img_request->kref);
2002 dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev,
2003 write_request ? "write" : "read", offset, length,
2009 static void rbd_img_request_destroy(struct kref *kref)
2011 struct rbd_img_request *img_request;
2012 struct rbd_obj_request *obj_request;
2013 struct rbd_obj_request *next_obj_request;
2015 img_request = container_of(kref, struct rbd_img_request, kref);
2017 dout("%s: img %p\n", __func__, img_request);
2019 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2020 rbd_img_obj_request_del(img_request, obj_request);
2021 rbd_assert(img_request->obj_request_count == 0);
2023 if (img_request_layered_test(img_request)) {
2024 img_request_layered_clear(img_request);
2025 rbd_dev_parent_put(img_request->rbd_dev);
2028 if (img_request_write_test(img_request))
2029 ceph_put_snap_context(img_request->snapc);
2031 kmem_cache_free(rbd_img_request_cache, img_request);
2034 static struct rbd_img_request *rbd_parent_request_create(
2035 struct rbd_obj_request *obj_request,
2036 u64 img_offset, u64 length)
2038 struct rbd_img_request *parent_request;
2039 struct rbd_device *rbd_dev;
2041 rbd_assert(obj_request->img_request);
2042 rbd_dev = obj_request->img_request->rbd_dev;
2044 parent_request = rbd_img_request_create(rbd_dev->parent,
2045 img_offset, length, false);
2046 if (!parent_request)
2049 img_request_child_set(parent_request);
2050 rbd_obj_request_get(obj_request);
2051 parent_request->obj_request = obj_request;
2053 return parent_request;
2056 static void rbd_parent_request_destroy(struct kref *kref)
2058 struct rbd_img_request *parent_request;
2059 struct rbd_obj_request *orig_request;
2061 parent_request = container_of(kref, struct rbd_img_request, kref);
2062 orig_request = parent_request->obj_request;
2064 parent_request->obj_request = NULL;
2065 rbd_obj_request_put(orig_request);
2066 img_request_child_clear(parent_request);
2068 rbd_img_request_destroy(kref);
2071 static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request)
2073 struct rbd_img_request *img_request;
2074 unsigned int xferred;
2078 rbd_assert(obj_request_img_data_test(obj_request));
2079 img_request = obj_request->img_request;
2081 rbd_assert(obj_request->xferred <= (u64)UINT_MAX);
2082 xferred = (unsigned int)obj_request->xferred;
2083 result = obj_request->result;
2085 struct rbd_device *rbd_dev = img_request->rbd_dev;
2087 rbd_warn(rbd_dev, "%s %llx at %llx (%llx)\n",
2088 img_request_write_test(img_request) ? "write" : "read",
2089 obj_request->length, obj_request->img_offset,
2090 obj_request->offset);
2091 rbd_warn(rbd_dev, " result %d xferred %x\n",
2093 if (!img_request->result)
2094 img_request->result = result;
2097 /* Image object requests don't own their page array */
2099 if (obj_request->type == OBJ_REQUEST_PAGES) {
2100 obj_request->pages = NULL;
2101 obj_request->page_count = 0;
2104 if (img_request_child_test(img_request)) {
2105 rbd_assert(img_request->obj_request != NULL);
2106 more = obj_request->which < img_request->obj_request_count - 1;
2108 rbd_assert(img_request->rq != NULL);
2109 more = blk_end_request(img_request->rq, result, xferred);
2115 static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
2117 struct rbd_img_request *img_request;
2118 u32 which = obj_request->which;
2121 rbd_assert(obj_request_img_data_test(obj_request));
2122 img_request = obj_request->img_request;
2124 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
2125 rbd_assert(img_request != NULL);
2126 rbd_assert(img_request->obj_request_count > 0);
2127 rbd_assert(which != BAD_WHICH);
2128 rbd_assert(which < img_request->obj_request_count);
2129 rbd_assert(which >= img_request->next_completion);
2131 spin_lock_irq(&img_request->completion_lock);
2132 if (which != img_request->next_completion)
2135 for_each_obj_request_from(img_request, obj_request) {
2137 rbd_assert(which < img_request->obj_request_count);
2139 if (!obj_request_done_test(obj_request))
2141 more = rbd_img_obj_end_request(obj_request);
2145 rbd_assert(more ^ (which == img_request->obj_request_count));
2146 img_request->next_completion = which;
2148 spin_unlock_irq(&img_request->completion_lock);
2151 rbd_img_request_complete(img_request);
2155 * Split up an image request into one or more object requests, each
2156 * to a different object. The "type" parameter indicates whether
2157 * "data_desc" is the pointer to the head of a list of bio
2158 * structures, or the base of a page array. In either case this
2159 * function assumes data_desc describes memory sufficient to hold
2160 * all data described by the image request.
2162 static int rbd_img_request_fill(struct rbd_img_request *img_request,
2163 enum obj_request_type type,
2166 struct rbd_device *rbd_dev = img_request->rbd_dev;
2167 struct rbd_obj_request *obj_request = NULL;
2168 struct rbd_obj_request *next_obj_request;
2169 bool write_request = img_request_write_test(img_request);
2170 struct bio *bio_list;
2171 unsigned int bio_offset = 0;
2172 struct page **pages;
2177 dout("%s: img %p type %d data_desc %p\n", __func__, img_request,
2178 (int)type, data_desc);
2180 opcode = write_request ? CEPH_OSD_OP_WRITE : CEPH_OSD_OP_READ;
2181 img_offset = img_request->offset;
2182 resid = img_request->length;
2183 rbd_assert(resid > 0);
2185 if (type == OBJ_REQUEST_BIO) {
2186 bio_list = data_desc;
2187 rbd_assert(img_offset == bio_list->bi_sector << SECTOR_SHIFT);
2189 rbd_assert(type == OBJ_REQUEST_PAGES);
2194 struct ceph_osd_request *osd_req;
2195 const char *object_name;
2199 object_name = rbd_segment_name(rbd_dev, img_offset);
2202 offset = rbd_segment_offset(rbd_dev, img_offset);
2203 length = rbd_segment_length(rbd_dev, img_offset, resid);
2204 obj_request = rbd_obj_request_create(object_name,
2205 offset, length, type);
2206 /* object request has its own copy of the object name */
2207 rbd_segment_name_free(object_name);
2211 if (type == OBJ_REQUEST_BIO) {
2212 unsigned int clone_size;
2214 rbd_assert(length <= (u64)UINT_MAX);
2215 clone_size = (unsigned int)length;
2216 obj_request->bio_list =
2217 bio_chain_clone_range(&bio_list,
2221 if (!obj_request->bio_list)
2224 unsigned int page_count;
2226 obj_request->pages = pages;
2227 page_count = (u32)calc_pages_for(offset, length);
2228 obj_request->page_count = page_count;
2229 if ((offset + length) & ~PAGE_MASK)
2230 page_count--; /* more on last page */
2231 pages += page_count;
2234 osd_req = rbd_osd_req_create(rbd_dev, write_request,
2238 obj_request->osd_req = osd_req;
2239 obj_request->callback = rbd_img_obj_callback;
2241 osd_req_op_extent_init(osd_req, 0, opcode, offset, length,
2243 if (type == OBJ_REQUEST_BIO)
2244 osd_req_op_extent_osd_data_bio(osd_req, 0,
2245 obj_request->bio_list, length);
2247 osd_req_op_extent_osd_data_pages(osd_req, 0,
2248 obj_request->pages, length,
2249 offset & ~PAGE_MASK, false, false);
2252 rbd_osd_req_format_write(obj_request);
2254 rbd_osd_req_format_read(obj_request);
2256 obj_request->img_offset = img_offset;
2257 rbd_img_obj_request_add(img_request, obj_request);
2259 img_offset += length;
2266 rbd_obj_request_put(obj_request);
2268 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2269 rbd_obj_request_put(obj_request);
2275 rbd_img_obj_copyup_callback(struct rbd_obj_request *obj_request)
2277 struct rbd_img_request *img_request;
2278 struct rbd_device *rbd_dev;
2279 struct page **pages;
2282 rbd_assert(obj_request->type == OBJ_REQUEST_BIO);
2283 rbd_assert(obj_request_img_data_test(obj_request));
2284 img_request = obj_request->img_request;
2285 rbd_assert(img_request);
2287 rbd_dev = img_request->rbd_dev;
2288 rbd_assert(rbd_dev);
2290 pages = obj_request->copyup_pages;
2291 rbd_assert(pages != NULL);
2292 obj_request->copyup_pages = NULL;
2293 page_count = obj_request->copyup_page_count;
2294 rbd_assert(page_count);
2295 obj_request->copyup_page_count = 0;
2296 ceph_release_page_vector(pages, page_count);
2299 * We want the transfer count to reflect the size of the
2300 * original write request. There is no such thing as a
2301 * successful short write, so if the request was successful
2302 * we can just set it to the originally-requested length.
2304 if (!obj_request->result)
2305 obj_request->xferred = obj_request->length;
2307 /* Finish up with the normal image object callback */
2309 rbd_img_obj_callback(obj_request);
2313 rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request)
2315 struct rbd_obj_request *orig_request;
2316 struct ceph_osd_request *osd_req;
2317 struct ceph_osd_client *osdc;
2318 struct rbd_device *rbd_dev;
2319 struct page **pages;
2326 rbd_assert(img_request_child_test(img_request));
2328 /* First get what we need from the image request */
2330 pages = img_request->copyup_pages;
2331 rbd_assert(pages != NULL);
2332 img_request->copyup_pages = NULL;
2333 page_count = img_request->copyup_page_count;
2334 rbd_assert(page_count);
2335 img_request->copyup_page_count = 0;
2337 orig_request = img_request->obj_request;
2338 rbd_assert(orig_request != NULL);
2339 rbd_assert(obj_request_type_valid(orig_request->type));
2340 img_result = img_request->result;
2341 parent_length = img_request->length;
2342 rbd_assert(parent_length == img_request->xferred);
2343 rbd_img_request_put(img_request);
2345 rbd_assert(orig_request->img_request);
2346 rbd_dev = orig_request->img_request->rbd_dev;
2347 rbd_assert(rbd_dev);
2350 * If the overlap has become 0 (most likely because the
2351 * image has been flattened) we need to free the pages
2352 * and re-submit the original write request.
2354 if (!rbd_dev->parent_overlap) {
2355 struct ceph_osd_client *osdc;
2357 ceph_release_page_vector(pages, page_count);
2358 osdc = &rbd_dev->rbd_client->client->osdc;
2359 img_result = rbd_obj_request_submit(osdc, orig_request);
2368 * The original osd request is of no use to use any more.
2369 * We need a new one that can hold the two ops in a copyup
2370 * request. Allocate the new copyup osd request for the
2371 * original request, and release the old one.
2373 img_result = -ENOMEM;
2374 osd_req = rbd_osd_req_create_copyup(orig_request);
2377 rbd_osd_req_destroy(orig_request->osd_req);
2378 orig_request->osd_req = osd_req;
2379 orig_request->copyup_pages = pages;
2380 orig_request->copyup_page_count = page_count;
2382 /* Initialize the copyup op */
2384 osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup");
2385 osd_req_op_cls_request_data_pages(osd_req, 0, pages, parent_length, 0,
2388 /* Then the original write request op */
2390 offset = orig_request->offset;
2391 length = orig_request->length;
2392 osd_req_op_extent_init(osd_req, 1, CEPH_OSD_OP_WRITE,
2393 offset, length, 0, 0);
2394 if (orig_request->type == OBJ_REQUEST_BIO)
2395 osd_req_op_extent_osd_data_bio(osd_req, 1,
2396 orig_request->bio_list, length);
2398 osd_req_op_extent_osd_data_pages(osd_req, 1,
2399 orig_request->pages, length,
2400 offset & ~PAGE_MASK, false, false);
2402 rbd_osd_req_format_write(orig_request);
2404 /* All set, send it off. */
2406 orig_request->callback = rbd_img_obj_copyup_callback;
2407 osdc = &rbd_dev->rbd_client->client->osdc;
2408 img_result = rbd_obj_request_submit(osdc, orig_request);
2412 /* Record the error code and complete the request */
2414 orig_request->result = img_result;
2415 orig_request->xferred = 0;
2416 obj_request_done_set(orig_request);
2417 rbd_obj_request_complete(orig_request);
2421 * Read from the parent image the range of data that covers the
2422 * entire target of the given object request. This is used for
2423 * satisfying a layered image write request when the target of an
2424 * object request from the image request does not exist.
2426 * A page array big enough to hold the returned data is allocated
2427 * and supplied to rbd_img_request_fill() as the "data descriptor."
2428 * When the read completes, this page array will be transferred to
2429 * the original object request for the copyup operation.
2431 * If an error occurs, record it as the result of the original
2432 * object request and mark it done so it gets completed.
2434 static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request)
2436 struct rbd_img_request *img_request = NULL;
2437 struct rbd_img_request *parent_request = NULL;
2438 struct rbd_device *rbd_dev;
2441 struct page **pages = NULL;
2445 rbd_assert(obj_request_img_data_test(obj_request));
2446 rbd_assert(obj_request_type_valid(obj_request->type));
2448 img_request = obj_request->img_request;
2449 rbd_assert(img_request != NULL);
2450 rbd_dev = img_request->rbd_dev;
2451 rbd_assert(rbd_dev->parent != NULL);
2454 * Determine the byte range covered by the object in the
2455 * child image to which the original request was to be sent.
2457 img_offset = obj_request->img_offset - obj_request->offset;
2458 length = (u64)1 << rbd_dev->header.obj_order;
2461 * There is no defined parent data beyond the parent
2462 * overlap, so limit what we read at that boundary if
2465 if (img_offset + length > rbd_dev->parent_overlap) {
2466 rbd_assert(img_offset < rbd_dev->parent_overlap);
2467 length = rbd_dev->parent_overlap - img_offset;
2471 * Allocate a page array big enough to receive the data read
2474 page_count = (u32)calc_pages_for(0, length);
2475 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2476 if (IS_ERR(pages)) {
2477 result = PTR_ERR(pages);
2483 parent_request = rbd_parent_request_create(obj_request,
2484 img_offset, length);
2485 if (!parent_request)
2488 result = rbd_img_request_fill(parent_request, OBJ_REQUEST_PAGES, pages);
2491 parent_request->copyup_pages = pages;
2492 parent_request->copyup_page_count = page_count;
2494 parent_request->callback = rbd_img_obj_parent_read_full_callback;
2495 result = rbd_img_request_submit(parent_request);
2499 parent_request->copyup_pages = NULL;
2500 parent_request->copyup_page_count = 0;
2501 parent_request->obj_request = NULL;
2502 rbd_obj_request_put(obj_request);
2505 ceph_release_page_vector(pages, page_count);
2507 rbd_img_request_put(parent_request);
2508 obj_request->result = result;
2509 obj_request->xferred = 0;
2510 obj_request_done_set(obj_request);
2515 static void rbd_img_obj_exists_callback(struct rbd_obj_request *obj_request)
2517 struct rbd_obj_request *orig_request;
2518 struct rbd_device *rbd_dev;
2521 rbd_assert(!obj_request_img_data_test(obj_request));
2524 * All we need from the object request is the original
2525 * request and the result of the STAT op. Grab those, then
2526 * we're done with the request.
2528 orig_request = obj_request->obj_request;
2529 obj_request->obj_request = NULL;
2530 rbd_assert(orig_request);
2531 rbd_assert(orig_request->img_request);
2533 result = obj_request->result;
2534 obj_request->result = 0;
2536 dout("%s: obj %p for obj %p result %d %llu/%llu\n", __func__,
2537 obj_request, orig_request, result,
2538 obj_request->xferred, obj_request->length);
2539 rbd_obj_request_put(obj_request);
2542 * If the overlap has become 0 (most likely because the
2543 * image has been flattened) we need to free the pages
2544 * and re-submit the original write request.
2546 rbd_dev = orig_request->img_request->rbd_dev;
2547 if (!rbd_dev->parent_overlap) {
2548 struct ceph_osd_client *osdc;
2550 rbd_obj_request_put(orig_request);
2551 osdc = &rbd_dev->rbd_client->client->osdc;
2552 result = rbd_obj_request_submit(osdc, orig_request);
2558 * Our only purpose here is to determine whether the object
2559 * exists, and we don't want to treat the non-existence as
2560 * an error. If something else comes back, transfer the
2561 * error to the original request and complete it now.
2564 obj_request_existence_set(orig_request, true);
2565 } else if (result == -ENOENT) {
2566 obj_request_existence_set(orig_request, false);
2567 } else if (result) {
2568 orig_request->result = result;
2573 * Resubmit the original request now that we have recorded
2574 * whether the target object exists.
2576 orig_request->result = rbd_img_obj_request_submit(orig_request);
2578 if (orig_request->result)
2579 rbd_obj_request_complete(orig_request);
2580 rbd_obj_request_put(orig_request);
2583 static int rbd_img_obj_exists_submit(struct rbd_obj_request *obj_request)
2585 struct rbd_obj_request *stat_request;
2586 struct rbd_device *rbd_dev;
2587 struct ceph_osd_client *osdc;
2588 struct page **pages = NULL;
2594 * The response data for a STAT call consists of:
2601 size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32);
2602 page_count = (u32)calc_pages_for(0, size);
2603 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2605 return PTR_ERR(pages);
2608 stat_request = rbd_obj_request_create(obj_request->object_name, 0, 0,
2613 rbd_obj_request_get(obj_request);
2614 stat_request->obj_request = obj_request;
2615 stat_request->pages = pages;
2616 stat_request->page_count = page_count;
2618 rbd_assert(obj_request->img_request);
2619 rbd_dev = obj_request->img_request->rbd_dev;
2620 stat_request->osd_req = rbd_osd_req_create(rbd_dev, false,
2622 if (!stat_request->osd_req)
2624 stat_request->callback = rbd_img_obj_exists_callback;
2626 osd_req_op_init(stat_request->osd_req, 0, CEPH_OSD_OP_STAT);
2627 osd_req_op_raw_data_in_pages(stat_request->osd_req, 0, pages, size, 0,
2629 rbd_osd_req_format_read(stat_request);
2631 osdc = &rbd_dev->rbd_client->client->osdc;
2632 ret = rbd_obj_request_submit(osdc, stat_request);
2635 rbd_obj_request_put(obj_request);
2640 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request)
2642 struct rbd_img_request *img_request;
2643 struct rbd_device *rbd_dev;
2646 rbd_assert(obj_request_img_data_test(obj_request));
2648 img_request = obj_request->img_request;
2649 rbd_assert(img_request);
2650 rbd_dev = img_request->rbd_dev;
2653 * Only writes to layered images need special handling.
2654 * Reads and non-layered writes are simple object requests.
2655 * Layered writes that start beyond the end of the overlap
2656 * with the parent have no parent data, so they too are
2657 * simple object requests. Finally, if the target object is
2658 * known to already exist, its parent data has already been
2659 * copied, so a write to the object can also be handled as a
2660 * simple object request.
2662 if (!img_request_write_test(img_request) ||
2663 !img_request_layered_test(img_request) ||
2664 rbd_dev->parent_overlap <= obj_request->img_offset ||
2665 ((known = obj_request_known_test(obj_request)) &&
2666 obj_request_exists_test(obj_request))) {
2668 struct rbd_device *rbd_dev;
2669 struct ceph_osd_client *osdc;
2671 rbd_dev = obj_request->img_request->rbd_dev;
2672 osdc = &rbd_dev->rbd_client->client->osdc;
2674 return rbd_obj_request_submit(osdc, obj_request);
2678 * It's a layered write. The target object might exist but
2679 * we may not know that yet. If we know it doesn't exist,
2680 * start by reading the data for the full target object from
2681 * the parent so we can use it for a copyup to the target.
2684 return rbd_img_obj_parent_read_full(obj_request);
2686 /* We don't know whether the target exists. Go find out. */
2688 return rbd_img_obj_exists_submit(obj_request);
2691 static int rbd_img_request_submit(struct rbd_img_request *img_request)
2693 struct rbd_obj_request *obj_request;
2694 struct rbd_obj_request *next_obj_request;
2696 dout("%s: img %p\n", __func__, img_request);
2697 for_each_obj_request_safe(img_request, obj_request, next_obj_request) {
2700 ret = rbd_img_obj_request_submit(obj_request);
2708 static void rbd_img_parent_read_callback(struct rbd_img_request *img_request)
2710 struct rbd_obj_request *obj_request;
2711 struct rbd_device *rbd_dev;
2716 rbd_assert(img_request_child_test(img_request));
2718 /* First get what we need from the image request and release it */
2720 obj_request = img_request->obj_request;
2721 img_xferred = img_request->xferred;
2722 img_result = img_request->result;
2723 rbd_img_request_put(img_request);
2726 * If the overlap has become 0 (most likely because the
2727 * image has been flattened) we need to re-submit the
2730 rbd_assert(obj_request);
2731 rbd_assert(obj_request->img_request);
2732 rbd_dev = obj_request->img_request->rbd_dev;
2733 if (!rbd_dev->parent_overlap) {
2734 struct ceph_osd_client *osdc;
2736 osdc = &rbd_dev->rbd_client->client->osdc;
2737 img_result = rbd_obj_request_submit(osdc, obj_request);
2742 obj_request->result = img_result;
2743 if (obj_request->result)
2747 * We need to zero anything beyond the parent overlap
2748 * boundary. Since rbd_img_obj_request_read_callback()
2749 * will zero anything beyond the end of a short read, an
2750 * easy way to do this is to pretend the data from the
2751 * parent came up short--ending at the overlap boundary.
2753 rbd_assert(obj_request->img_offset < U64_MAX - obj_request->length);
2754 obj_end = obj_request->img_offset + obj_request->length;
2755 if (obj_end > rbd_dev->parent_overlap) {
2758 if (obj_request->img_offset < rbd_dev->parent_overlap)
2759 xferred = rbd_dev->parent_overlap -
2760 obj_request->img_offset;
2762 obj_request->xferred = min(img_xferred, xferred);
2764 obj_request->xferred = img_xferred;
2767 rbd_img_obj_request_read_callback(obj_request);
2768 rbd_obj_request_complete(obj_request);
2771 static void rbd_img_parent_read(struct rbd_obj_request *obj_request)
2773 struct rbd_img_request *img_request;
2776 rbd_assert(obj_request_img_data_test(obj_request));
2777 rbd_assert(obj_request->img_request != NULL);
2778 rbd_assert(obj_request->result == (s32) -ENOENT);
2779 rbd_assert(obj_request_type_valid(obj_request->type));
2781 /* rbd_read_finish(obj_request, obj_request->length); */
2782 img_request = rbd_parent_request_create(obj_request,
2783 obj_request->img_offset,
2784 obj_request->length);
2789 if (obj_request->type == OBJ_REQUEST_BIO)
2790 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
2791 obj_request->bio_list);
2793 result = rbd_img_request_fill(img_request, OBJ_REQUEST_PAGES,
2794 obj_request->pages);
2798 img_request->callback = rbd_img_parent_read_callback;
2799 result = rbd_img_request_submit(img_request);
2806 rbd_img_request_put(img_request);
2807 obj_request->result = result;
2808 obj_request->xferred = 0;
2809 obj_request_done_set(obj_request);
2812 static int rbd_obj_notify_ack(struct rbd_device *rbd_dev, u64 notify_id)
2814 struct rbd_obj_request *obj_request;
2815 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2818 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
2819 OBJ_REQUEST_NODATA);
2824 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
2825 if (!obj_request->osd_req)
2827 obj_request->callback = rbd_obj_request_put;
2829 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK,
2831 rbd_osd_req_format_read(obj_request);
2833 ret = rbd_obj_request_submit(osdc, obj_request);
2836 rbd_obj_request_put(obj_request);
2841 static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
2843 struct rbd_device *rbd_dev = (struct rbd_device *)data;
2849 dout("%s: \"%s\" notify_id %llu opcode %u\n", __func__,
2850 rbd_dev->header_name, (unsigned long long)notify_id,
2851 (unsigned int)opcode);
2852 ret = rbd_dev_refresh(rbd_dev);
2854 rbd_warn(rbd_dev, ": header refresh error (%d)\n", ret);
2856 rbd_obj_notify_ack(rbd_dev, notify_id);
2860 * Request sync osd watch/unwatch. The value of "start" determines
2861 * whether a watch request is being initiated or torn down.
2863 static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, bool start)
2865 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2866 struct rbd_obj_request *obj_request;
2869 rbd_assert(start ^ !!rbd_dev->watch_event);
2870 rbd_assert(start ^ !!rbd_dev->watch_request);
2873 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
2874 &rbd_dev->watch_event);
2877 rbd_assert(rbd_dev->watch_event != NULL);
2881 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
2882 OBJ_REQUEST_NODATA);
2886 obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, obj_request);
2887 if (!obj_request->osd_req)
2891 ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
2893 ceph_osdc_unregister_linger_request(osdc,
2894 rbd_dev->watch_request->osd_req);
2896 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
2897 rbd_dev->watch_event->cookie, 0, start ? 1 : 0);
2898 rbd_osd_req_format_write(obj_request);
2900 ret = rbd_obj_request_submit(osdc, obj_request);
2903 ret = rbd_obj_request_wait(obj_request);
2906 ret = obj_request->result;
2911 * A watch request is set to linger, so the underlying osd
2912 * request won't go away until we unregister it. We retain
2913 * a pointer to the object request during that time (in
2914 * rbd_dev->watch_request), so we'll keep a reference to
2915 * it. We'll drop that reference (below) after we've
2919 rbd_dev->watch_request = obj_request;
2924 /* We have successfully torn down the watch request */
2926 rbd_obj_request_put(rbd_dev->watch_request);
2927 rbd_dev->watch_request = NULL;
2929 /* Cancel the event if we're tearing down, or on error */
2930 ceph_osdc_cancel_event(rbd_dev->watch_event);
2931 rbd_dev->watch_event = NULL;
2933 rbd_obj_request_put(obj_request);
2939 * Synchronous osd object method call. Returns the number of bytes
2940 * returned in the outbound buffer, or a negative error code.
2942 static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
2943 const char *object_name,
2944 const char *class_name,
2945 const char *method_name,
2946 const void *outbound,
2947 size_t outbound_size,
2949 size_t inbound_size)
2951 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2952 struct rbd_obj_request *obj_request;
2953 struct page **pages;
2958 * Method calls are ultimately read operations. The result
2959 * should placed into the inbound buffer provided. They
2960 * also supply outbound data--parameters for the object
2961 * method. Currently if this is present it will be a
2964 page_count = (u32)calc_pages_for(0, inbound_size);
2965 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2967 return PTR_ERR(pages);
2970 obj_request = rbd_obj_request_create(object_name, 0, inbound_size,
2975 obj_request->pages = pages;
2976 obj_request->page_count = page_count;
2978 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
2979 if (!obj_request->osd_req)
2982 osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL,
2983 class_name, method_name);
2984 if (outbound_size) {
2985 struct ceph_pagelist *pagelist;
2987 pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS);
2991 ceph_pagelist_init(pagelist);
2992 ceph_pagelist_append(pagelist, outbound, outbound_size);
2993 osd_req_op_cls_request_data_pagelist(obj_request->osd_req, 0,
2996 osd_req_op_cls_response_data_pages(obj_request->osd_req, 0,
2997 obj_request->pages, inbound_size,
2999 rbd_osd_req_format_read(obj_request);
3001 ret = rbd_obj_request_submit(osdc, obj_request);
3004 ret = rbd_obj_request_wait(obj_request);
3008 ret = obj_request->result;
3012 rbd_assert(obj_request->xferred < (u64)INT_MAX);
3013 ret = (int)obj_request->xferred;
3014 ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred);
3017 rbd_obj_request_put(obj_request);
3019 ceph_release_page_vector(pages, page_count);
3024 static void rbd_request_fn(struct request_queue *q)
3025 __releases(q->queue_lock) __acquires(q->queue_lock)
3027 struct rbd_device *rbd_dev = q->queuedata;
3028 bool read_only = rbd_dev->mapping.read_only;
3032 while ((rq = blk_fetch_request(q))) {
3033 bool write_request = rq_data_dir(rq) == WRITE;
3034 struct rbd_img_request *img_request;
3038 /* Ignore any non-FS requests that filter through. */
3040 if (rq->cmd_type != REQ_TYPE_FS) {
3041 dout("%s: non-fs request type %d\n", __func__,
3042 (int) rq->cmd_type);
3043 __blk_end_request_all(rq, 0);
3047 /* Ignore/skip any zero-length requests */
3049 offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT;
3050 length = (u64) blk_rq_bytes(rq);
3053 dout("%s: zero-length request\n", __func__);
3054 __blk_end_request_all(rq, 0);
3058 spin_unlock_irq(q->queue_lock);
3060 /* Disallow writes to a read-only device */
3062 if (write_request) {
3066 rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP);
3070 * Quit early if the mapped snapshot no longer
3071 * exists. It's still possible the snapshot will
3072 * have disappeared by the time our request arrives
3073 * at the osd, but there's no sense in sending it if
3076 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) {
3077 dout("request for non-existent snapshot");
3078 rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP);
3084 if (offset && length > U64_MAX - offset + 1) {
3085 rbd_warn(rbd_dev, "bad request range (%llu~%llu)\n",
3087 goto end_request; /* Shouldn't happen */
3091 if (offset + length > rbd_dev->mapping.size) {
3092 rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)\n",
3093 offset, length, rbd_dev->mapping.size);
3098 img_request = rbd_img_request_create(rbd_dev, offset, length,
3103 img_request->rq = rq;
3105 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
3108 result = rbd_img_request_submit(img_request);
3110 rbd_img_request_put(img_request);
3112 spin_lock_irq(q->queue_lock);
3114 rbd_warn(rbd_dev, "%s %llx at %llx result %d\n",
3115 write_request ? "write" : "read",
3116 length, offset, result);
3118 __blk_end_request_all(rq, result);
3124 * a queue callback. Makes sure that we don't create a bio that spans across
3125 * multiple osd objects. One exception would be with a single page bios,
3126 * which we handle later at bio_chain_clone_range()
3128 static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
3129 struct bio_vec *bvec)
3131 struct rbd_device *rbd_dev = q->queuedata;
3132 sector_t sector_offset;
3133 sector_t sectors_per_obj;
3134 sector_t obj_sector_offset;
3138 * Find how far into its rbd object the partition-relative
3139 * bio start sector is to offset relative to the enclosing
3142 sector_offset = get_start_sect(bmd->bi_bdev) + bmd->bi_sector;
3143 sectors_per_obj = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT);
3144 obj_sector_offset = sector_offset & (sectors_per_obj - 1);
3147 * Compute the number of bytes from that offset to the end
3148 * of the object. Account for what's already used by the bio.
3150 ret = (int) (sectors_per_obj - obj_sector_offset) << SECTOR_SHIFT;
3151 if (ret > bmd->bi_size)
3152 ret -= bmd->bi_size;
3157 * Don't send back more than was asked for. And if the bio
3158 * was empty, let the whole thing through because: "Note
3159 * that a block device *must* allow a single page to be
3160 * added to an empty bio."
3162 rbd_assert(bvec->bv_len <= PAGE_SIZE);
3163 if (ret > (int) bvec->bv_len || !bmd->bi_size)
3164 ret = (int) bvec->bv_len;
3169 static void rbd_free_disk(struct rbd_device *rbd_dev)
3171 struct gendisk *disk = rbd_dev->disk;
3176 rbd_dev->disk = NULL;
3177 if (disk->flags & GENHD_FL_UP) {
3180 blk_cleanup_queue(disk->queue);
3185 static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
3186 const char *object_name,
3187 u64 offset, u64 length, void *buf)
3190 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3191 struct rbd_obj_request *obj_request;
3192 struct page **pages = NULL;
3197 page_count = (u32) calc_pages_for(offset, length);
3198 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
3200 ret = PTR_ERR(pages);
3203 obj_request = rbd_obj_request_create(object_name, offset, length,
3208 obj_request->pages = pages;
3209 obj_request->page_count = page_count;
3211 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
3212 if (!obj_request->osd_req)
3215 osd_req_op_extent_init(obj_request->osd_req, 0, CEPH_OSD_OP_READ,
3216 offset, length, 0, 0);
3217 osd_req_op_extent_osd_data_pages(obj_request->osd_req, 0,
3219 obj_request->length,
3220 obj_request->offset & ~PAGE_MASK,
3222 rbd_osd_req_format_read(obj_request);
3224 ret = rbd_obj_request_submit(osdc, obj_request);
3227 ret = rbd_obj_request_wait(obj_request);
3231 ret = obj_request->result;
3235 rbd_assert(obj_request->xferred <= (u64) SIZE_MAX);
3236 size = (size_t) obj_request->xferred;
3237 ceph_copy_from_page_vector(pages, buf, 0, size);
3238 rbd_assert(size <= (size_t)INT_MAX);
3242 rbd_obj_request_put(obj_request);
3244 ceph_release_page_vector(pages, page_count);
3250 * Read the complete header for the given rbd device. On successful
3251 * return, the rbd_dev->header field will contain up-to-date
3252 * information about the image.
3254 static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
3256 struct rbd_image_header_ondisk *ondisk = NULL;
3263 * The complete header will include an array of its 64-bit
3264 * snapshot ids, followed by the names of those snapshots as
3265 * a contiguous block of NUL-terminated strings. Note that
3266 * the number of snapshots could change by the time we read
3267 * it in, in which case we re-read it.
3274 size = sizeof (*ondisk);
3275 size += snap_count * sizeof (struct rbd_image_snap_ondisk);
3277 ondisk = kmalloc(size, GFP_KERNEL);
3281 ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name,
3285 if ((size_t)ret < size) {
3287 rbd_warn(rbd_dev, "short header read (want %zd got %d)",
3291 if (!rbd_dev_ondisk_valid(ondisk)) {
3293 rbd_warn(rbd_dev, "invalid header");
3297 names_size = le64_to_cpu(ondisk->snap_names_len);
3298 want_count = snap_count;
3299 snap_count = le32_to_cpu(ondisk->snap_count);
3300 } while (snap_count != want_count);
3302 ret = rbd_header_from_disk(rbd_dev, ondisk);
3310 * Clear the rbd device's EXISTS flag if the snapshot it's mapped to
3311 * has disappeared from the (just updated) snapshot context.
3313 static void rbd_exists_validate(struct rbd_device *rbd_dev)
3317 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags))
3320 snap_id = rbd_dev->spec->snap_id;
3321 if (snap_id == CEPH_NOSNAP)
3324 if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX)
3325 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
3328 static int rbd_dev_refresh(struct rbd_device *rbd_dev)
3333 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
3334 mapping_size = rbd_dev->mapping.size;
3335 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
3336 if (rbd_dev->image_format == 1)
3337 ret = rbd_dev_v1_header_info(rbd_dev);
3339 ret = rbd_dev_v2_header_info(rbd_dev);
3341 /* If it's a mapped snapshot, validate its EXISTS flag */
3343 rbd_exists_validate(rbd_dev);
3344 mutex_unlock(&ctl_mutex);
3345 if (mapping_size != rbd_dev->mapping.size) {
3348 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
3349 dout("setting size to %llu sectors", (unsigned long long)size);
3350 set_capacity(rbd_dev->disk, size);
3351 revalidate_disk(rbd_dev->disk);
3357 static int rbd_init_disk(struct rbd_device *rbd_dev)
3359 struct gendisk *disk;
3360 struct request_queue *q;
3363 /* create gendisk info */
3364 disk = alloc_disk(RBD_MINORS_PER_MAJOR);
3368 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
3370 disk->major = rbd_dev->major;
3371 disk->first_minor = 0;
3372 disk->fops = &rbd_bd_ops;
3373 disk->private_data = rbd_dev;
3375 q = blk_init_queue(rbd_request_fn, &rbd_dev->lock);
3379 /* We use the default size, but let's be explicit about it. */
3380 blk_queue_physical_block_size(q, SECTOR_SIZE);
3382 /* set io sizes to object size */
3383 segment_size = rbd_obj_bytes(&rbd_dev->header);
3384 blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
3385 blk_queue_max_segment_size(q, segment_size);
3386 blk_queue_io_min(q, segment_size);
3387 blk_queue_io_opt(q, segment_size);
3389 blk_queue_merge_bvec(q, rbd_merge_bvec);
3392 q->queuedata = rbd_dev;
3394 rbd_dev->disk = disk;
3407 static struct rbd_device *dev_to_rbd_dev(struct device *dev)
3409 return container_of(dev, struct rbd_device, dev);
3412 static ssize_t rbd_size_show(struct device *dev,
3413 struct device_attribute *attr, char *buf)
3415 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3417 return sprintf(buf, "%llu\n",
3418 (unsigned long long)rbd_dev->mapping.size);
3422 * Note this shows the features for whatever's mapped, which is not
3423 * necessarily the base image.
3425 static ssize_t rbd_features_show(struct device *dev,
3426 struct device_attribute *attr, char *buf)
3428 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3430 return sprintf(buf, "0x%016llx\n",
3431 (unsigned long long)rbd_dev->mapping.features);
3434 static ssize_t rbd_major_show(struct device *dev,
3435 struct device_attribute *attr, char *buf)
3437 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3440 return sprintf(buf, "%d\n", rbd_dev->major);
3442 return sprintf(buf, "(none)\n");
3446 static ssize_t rbd_client_id_show(struct device *dev,
3447 struct device_attribute *attr, char *buf)
3449 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3451 return sprintf(buf, "client%lld\n",
3452 ceph_client_id(rbd_dev->rbd_client->client));
3455 static ssize_t rbd_pool_show(struct device *dev,
3456 struct device_attribute *attr, char *buf)
3458 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3460 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
3463 static ssize_t rbd_pool_id_show(struct device *dev,
3464 struct device_attribute *attr, char *buf)
3466 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3468 return sprintf(buf, "%llu\n",
3469 (unsigned long long) rbd_dev->spec->pool_id);
3472 static ssize_t rbd_name_show(struct device *dev,
3473 struct device_attribute *attr, char *buf)
3475 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3477 if (rbd_dev->spec->image_name)
3478 return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
3480 return sprintf(buf, "(unknown)\n");
3483 static ssize_t rbd_image_id_show(struct device *dev,
3484 struct device_attribute *attr, char *buf)
3486 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3488 return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
3492 * Shows the name of the currently-mapped snapshot (or
3493 * RBD_SNAP_HEAD_NAME for the base image).
3495 static ssize_t rbd_snap_show(struct device *dev,
3496 struct device_attribute *attr,
3499 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3501 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
3505 * For an rbd v2 image, shows the pool id, image id, and snapshot id
3506 * for the parent image. If there is no parent, simply shows
3507 * "(no parent image)".
3509 static ssize_t rbd_parent_show(struct device *dev,
3510 struct device_attribute *attr,
3513 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3514 struct rbd_spec *spec = rbd_dev->parent_spec;
3519 return sprintf(buf, "(no parent image)\n");
3521 count = sprintf(bufp, "pool_id %llu\npool_name %s\n",
3522 (unsigned long long) spec->pool_id, spec->pool_name);
3527 count = sprintf(bufp, "image_id %s\nimage_name %s\n", spec->image_id,
3528 spec->image_name ? spec->image_name : "(unknown)");
3533 count = sprintf(bufp, "snap_id %llu\nsnap_name %s\n",
3534 (unsigned long long) spec->snap_id, spec->snap_name);
3539 count = sprintf(bufp, "overlap %llu\n", rbd_dev->parent_overlap);
3544 return (ssize_t) (bufp - buf);
3547 static ssize_t rbd_image_refresh(struct device *dev,
3548 struct device_attribute *attr,
3552 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3555 ret = rbd_dev_refresh(rbd_dev);
3557 rbd_warn(rbd_dev, ": manual header refresh error (%d)\n", ret);
3559 return ret < 0 ? ret : size;
3562 static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
3563 static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL);
3564 static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
3565 static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
3566 static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
3567 static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL);
3568 static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
3569 static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL);
3570 static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
3571 static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
3572 static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL);
3574 static struct attribute *rbd_attrs[] = {
3575 &dev_attr_size.attr,
3576 &dev_attr_features.attr,
3577 &dev_attr_major.attr,
3578 &dev_attr_client_id.attr,
3579 &dev_attr_pool.attr,
3580 &dev_attr_pool_id.attr,
3581 &dev_attr_name.attr,
3582 &dev_attr_image_id.attr,
3583 &dev_attr_current_snap.attr,
3584 &dev_attr_parent.attr,
3585 &dev_attr_refresh.attr,
3589 static struct attribute_group rbd_attr_group = {
3593 static const struct attribute_group *rbd_attr_groups[] = {
3598 static void rbd_sysfs_dev_release(struct device *dev)
3602 static struct device_type rbd_device_type = {
3604 .groups = rbd_attr_groups,
3605 .release = rbd_sysfs_dev_release,
3608 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
3610 kref_get(&spec->kref);
3615 static void rbd_spec_free(struct kref *kref);
3616 static void rbd_spec_put(struct rbd_spec *spec)
3619 kref_put(&spec->kref, rbd_spec_free);
3622 static struct rbd_spec *rbd_spec_alloc(void)
3624 struct rbd_spec *spec;
3626 spec = kzalloc(sizeof (*spec), GFP_KERNEL);
3629 kref_init(&spec->kref);
3634 static void rbd_spec_free(struct kref *kref)
3636 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
3638 kfree(spec->pool_name);
3639 kfree(spec->image_id);
3640 kfree(spec->image_name);
3641 kfree(spec->snap_name);
3645 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
3646 struct rbd_spec *spec)
3648 struct rbd_device *rbd_dev;
3650 rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL);
3654 spin_lock_init(&rbd_dev->lock);
3656 atomic_set(&rbd_dev->parent_ref, 0);
3657 INIT_LIST_HEAD(&rbd_dev->node);
3658 init_rwsem(&rbd_dev->header_rwsem);
3660 rbd_dev->spec = spec;
3661 rbd_dev->rbd_client = rbdc;
3663 /* Initialize the layout used for all rbd requests */
3665 rbd_dev->layout.fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3666 rbd_dev->layout.fl_stripe_count = cpu_to_le32(1);
3667 rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3668 rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id);
3673 static void rbd_dev_destroy(struct rbd_device *rbd_dev)
3675 rbd_put_client(rbd_dev->rbd_client);
3676 rbd_spec_put(rbd_dev->spec);
3681 * Get the size and object order for an image snapshot, or if
3682 * snap_id is CEPH_NOSNAP, gets this information for the base
3685 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
3686 u8 *order, u64 *snap_size)
3688 __le64 snapid = cpu_to_le64(snap_id);
3693 } __attribute__ ((packed)) size_buf = { 0 };
3695 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3697 &snapid, sizeof (snapid),
3698 &size_buf, sizeof (size_buf));
3699 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3702 if (ret < sizeof (size_buf))
3706 *order = size_buf.order;
3707 *snap_size = le64_to_cpu(size_buf.size);
3709 dout(" snap_id 0x%016llx order = %u, snap_size = %llu\n",
3710 (unsigned long long)snap_id, (unsigned int)*order,
3711 (unsigned long long)*snap_size);
3716 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
3718 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
3719 &rbd_dev->header.obj_order,
3720 &rbd_dev->header.image_size);
3723 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
3729 reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL);
3733 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3734 "rbd", "get_object_prefix", NULL, 0,
3735 reply_buf, RBD_OBJ_PREFIX_LEN_MAX);
3736 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3741 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
3742 p + ret, NULL, GFP_NOIO);
3745 if (IS_ERR(rbd_dev->header.object_prefix)) {
3746 ret = PTR_ERR(rbd_dev->header.object_prefix);
3747 rbd_dev->header.object_prefix = NULL;
3749 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix);
3757 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
3760 __le64 snapid = cpu_to_le64(snap_id);
3764 } __attribute__ ((packed)) features_buf = { 0 };
3768 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3769 "rbd", "get_features",
3770 &snapid, sizeof (snapid),
3771 &features_buf, sizeof (features_buf));
3772 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3775 if (ret < sizeof (features_buf))
3778 incompat = le64_to_cpu(features_buf.incompat);
3779 if (incompat & ~RBD_FEATURES_SUPPORTED)
3782 *snap_features = le64_to_cpu(features_buf.features);
3784 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
3785 (unsigned long long)snap_id,
3786 (unsigned long long)*snap_features,
3787 (unsigned long long)le64_to_cpu(features_buf.incompat));
3792 static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
3794 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
3795 &rbd_dev->header.features);
3798 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
3800 struct rbd_spec *parent_spec;
3802 void *reply_buf = NULL;
3811 parent_spec = rbd_spec_alloc();
3815 size = sizeof (__le64) + /* pool_id */
3816 sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */
3817 sizeof (__le64) + /* snap_id */
3818 sizeof (__le64); /* overlap */
3819 reply_buf = kmalloc(size, GFP_KERNEL);
3825 snapid = cpu_to_le64(CEPH_NOSNAP);
3826 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3827 "rbd", "get_parent",
3828 &snapid, sizeof (snapid),
3830 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3835 end = reply_buf + ret;
3837 ceph_decode_64_safe(&p, end, pool_id, out_err);
3838 if (pool_id == CEPH_NOPOOL) {
3840 * Either the parent never existed, or we have
3841 * record of it but the image got flattened so it no
3842 * longer has a parent. When the parent of a
3843 * layered image disappears we immediately set the
3844 * overlap to 0. The effect of this is that all new
3845 * requests will be treated as if the image had no
3848 if (rbd_dev->parent_overlap) {
3849 rbd_dev->parent_overlap = 0;
3851 rbd_dev_parent_put(rbd_dev);
3852 pr_info("%s: clone image has been flattened\n",
3853 rbd_dev->disk->disk_name);
3856 goto out; /* No parent? No problem. */
3859 /* The ceph file layout needs to fit pool id in 32 bits */
3862 if (pool_id > (u64)U32_MAX) {
3863 rbd_warn(NULL, "parent pool id too large (%llu > %u)\n",
3864 (unsigned long long)pool_id, U32_MAX);
3867 parent_spec->pool_id = pool_id;
3869 image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
3870 if (IS_ERR(image_id)) {
3871 ret = PTR_ERR(image_id);
3874 parent_spec->image_id = image_id;
3875 ceph_decode_64_safe(&p, end, parent_spec->snap_id, out_err);
3876 ceph_decode_64_safe(&p, end, overlap, out_err);
3879 rbd_spec_put(rbd_dev->parent_spec);
3880 rbd_dev->parent_spec = parent_spec;
3881 parent_spec = NULL; /* rbd_dev now owns this */
3882 rbd_dev->parent_overlap = overlap;
3884 rbd_warn(rbd_dev, "ignoring parent of clone with overlap 0\n");
3890 rbd_spec_put(parent_spec);
3895 static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
3899 __le64 stripe_count;
3900 } __attribute__ ((packed)) striping_info_buf = { 0 };
3901 size_t size = sizeof (striping_info_buf);
3908 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3909 "rbd", "get_stripe_unit_count", NULL, 0,
3910 (char *)&striping_info_buf, size);
3911 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3918 * We don't actually support the "fancy striping" feature
3919 * (STRIPINGV2) yet, but if the striping sizes are the
3920 * defaults the behavior is the same as before. So find
3921 * out, and only fail if the image has non-default values.
3924 obj_size = (u64)1 << rbd_dev->header.obj_order;
3925 p = &striping_info_buf;
3926 stripe_unit = ceph_decode_64(&p);
3927 if (stripe_unit != obj_size) {
3928 rbd_warn(rbd_dev, "unsupported stripe unit "
3929 "(got %llu want %llu)",
3930 stripe_unit, obj_size);
3933 stripe_count = ceph_decode_64(&p);
3934 if (stripe_count != 1) {
3935 rbd_warn(rbd_dev, "unsupported stripe count "
3936 "(got %llu want 1)", stripe_count);
3939 rbd_dev->header.stripe_unit = stripe_unit;
3940 rbd_dev->header.stripe_count = stripe_count;
3945 static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
3947 size_t image_id_size;
3952 void *reply_buf = NULL;
3954 char *image_name = NULL;
3957 rbd_assert(!rbd_dev->spec->image_name);
3959 len = strlen(rbd_dev->spec->image_id);
3960 image_id_size = sizeof (__le32) + len;
3961 image_id = kmalloc(image_id_size, GFP_KERNEL);
3966 end = image_id + image_id_size;
3967 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
3969 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
3970 reply_buf = kmalloc(size, GFP_KERNEL);
3974 ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY,
3975 "rbd", "dir_get_name",
3976 image_id, image_id_size,
3981 end = reply_buf + ret;
3983 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
3984 if (IS_ERR(image_name))
3987 dout("%s: name is %s len is %zd\n", __func__, image_name, len);
3995 static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
3997 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
3998 const char *snap_name;
4001 /* Skip over names until we find the one we are looking for */
4003 snap_name = rbd_dev->header.snap_names;
4004 while (which < snapc->num_snaps) {
4005 if (!strcmp(name, snap_name))
4006 return snapc->snaps[which];
4007 snap_name += strlen(snap_name) + 1;
4013 static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4015 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
4020 for (which = 0; !found && which < snapc->num_snaps; which++) {
4021 const char *snap_name;
4023 snap_id = snapc->snaps[which];
4024 snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
4025 if (IS_ERR(snap_name))
4027 found = !strcmp(name, snap_name);
4030 return found ? snap_id : CEPH_NOSNAP;
4034 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
4035 * no snapshot by that name is found, or if an error occurs.
4037 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4039 if (rbd_dev->image_format == 1)
4040 return rbd_v1_snap_id_by_name(rbd_dev, name);
4042 return rbd_v2_snap_id_by_name(rbd_dev, name);
4046 * When an rbd image has a parent image, it is identified by the
4047 * pool, image, and snapshot ids (not names). This function fills
4048 * in the names for those ids. (It's OK if we can't figure out the
4049 * name for an image id, but the pool and snapshot ids should always
4050 * exist and have names.) All names in an rbd spec are dynamically
4053 * When an image being mapped (not a parent) is probed, we have the
4054 * pool name and pool id, image name and image id, and the snapshot
4055 * name. The only thing we're missing is the snapshot id.
4057 static int rbd_dev_spec_update(struct rbd_device *rbd_dev)
4059 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4060 struct rbd_spec *spec = rbd_dev->spec;
4061 const char *pool_name;
4062 const char *image_name;
4063 const char *snap_name;
4067 * An image being mapped will have the pool name (etc.), but
4068 * we need to look up the snapshot id.
4070 if (spec->pool_name) {
4071 if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
4074 snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
4075 if (snap_id == CEPH_NOSNAP)
4077 spec->snap_id = snap_id;
4079 spec->snap_id = CEPH_NOSNAP;
4085 /* Get the pool name; we have to make our own copy of this */
4087 pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
4089 rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
4092 pool_name = kstrdup(pool_name, GFP_KERNEL);
4096 /* Fetch the image name; tolerate failure here */
4098 image_name = rbd_dev_image_name(rbd_dev);
4100 rbd_warn(rbd_dev, "unable to get image name");
4102 /* Look up the snapshot name, and make a copy */
4104 snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
4110 spec->pool_name = pool_name;
4111 spec->image_name = image_name;
4112 spec->snap_name = snap_name;
4122 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
4131 struct ceph_snap_context *snapc;
4135 * We'll need room for the seq value (maximum snapshot id),
4136 * snapshot count, and array of that many snapshot ids.
4137 * For now we have a fixed upper limit on the number we're
4138 * prepared to receive.
4140 size = sizeof (__le64) + sizeof (__le32) +
4141 RBD_MAX_SNAP_COUNT * sizeof (__le64);
4142 reply_buf = kzalloc(size, GFP_KERNEL);
4146 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4147 "rbd", "get_snapcontext", NULL, 0,
4149 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4154 end = reply_buf + ret;
4156 ceph_decode_64_safe(&p, end, seq, out);
4157 ceph_decode_32_safe(&p, end, snap_count, out);
4160 * Make sure the reported number of snapshot ids wouldn't go
4161 * beyond the end of our buffer. But before checking that,
4162 * make sure the computed size of the snapshot context we
4163 * allocate is representable in a size_t.
4165 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
4170 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
4174 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
4180 for (i = 0; i < snap_count; i++)
4181 snapc->snaps[i] = ceph_decode_64(&p);
4183 ceph_put_snap_context(rbd_dev->header.snapc);
4184 rbd_dev->header.snapc = snapc;
4186 dout(" snap context seq = %llu, snap_count = %u\n",
4187 (unsigned long long)seq, (unsigned int)snap_count);
4194 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
4205 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
4206 reply_buf = kmalloc(size, GFP_KERNEL);
4208 return ERR_PTR(-ENOMEM);
4210 snapid = cpu_to_le64(snap_id);
4211 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4212 "rbd", "get_snapshot_name",
4213 &snapid, sizeof (snapid),
4215 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4217 snap_name = ERR_PTR(ret);
4222 end = reply_buf + ret;
4223 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
4224 if (IS_ERR(snap_name))
4227 dout(" snap_id 0x%016llx snap_name = %s\n",
4228 (unsigned long long)snap_id, snap_name);
4235 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
4237 bool first_time = rbd_dev->header.object_prefix == NULL;
4240 down_write(&rbd_dev->header_rwsem);
4243 ret = rbd_dev_v2_header_onetime(rbd_dev);
4249 * If the image supports layering, get the parent info. We
4250 * need to probe the first time regardless. Thereafter we
4251 * only need to if there's a parent, to see if it has
4252 * disappeared due to the mapped image getting flattened.
4254 if (rbd_dev->header.features & RBD_FEATURE_LAYERING &&
4255 (first_time || rbd_dev->parent_spec)) {
4258 ret = rbd_dev_v2_parent_info(rbd_dev);
4263 * Print a warning if this is the initial probe and
4264 * the image has a parent. Don't print it if the
4265 * image now being probed is itself a parent. We
4266 * can tell at this point because we won't know its
4267 * pool name yet (just its pool id).
4269 warn = rbd_dev->parent_spec && rbd_dev->spec->pool_name;
4270 if (first_time && warn)
4271 rbd_warn(rbd_dev, "WARNING: kernel layering "
4272 "is EXPERIMENTAL!");
4275 ret = rbd_dev_v2_image_size(rbd_dev);
4279 if (rbd_dev->spec->snap_id == CEPH_NOSNAP)
4280 if (rbd_dev->mapping.size != rbd_dev->header.image_size)
4281 rbd_dev->mapping.size = rbd_dev->header.image_size;
4283 ret = rbd_dev_v2_snap_context(rbd_dev);
4284 dout("rbd_dev_v2_snap_context returned %d\n", ret);
4286 up_write(&rbd_dev->header_rwsem);
4291 static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
4296 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
4298 dev = &rbd_dev->dev;
4299 dev->bus = &rbd_bus_type;
4300 dev->type = &rbd_device_type;
4301 dev->parent = &rbd_root_dev;
4302 dev->release = rbd_dev_device_release;
4303 dev_set_name(dev, "%d", rbd_dev->dev_id);
4304 ret = device_register(dev);
4306 mutex_unlock(&ctl_mutex);
4311 static void rbd_bus_del_dev(struct rbd_device *rbd_dev)
4313 device_unregister(&rbd_dev->dev);
4316 static atomic64_t rbd_dev_id_max = ATOMIC64_INIT(0);
4319 * Get a unique rbd identifier for the given new rbd_dev, and add
4320 * the rbd_dev to the global list. The minimum rbd id is 1.
4322 static void rbd_dev_id_get(struct rbd_device *rbd_dev)
4324 rbd_dev->dev_id = atomic64_inc_return(&rbd_dev_id_max);
4326 spin_lock(&rbd_dev_list_lock);
4327 list_add_tail(&rbd_dev->node, &rbd_dev_list);
4328 spin_unlock(&rbd_dev_list_lock);
4329 dout("rbd_dev %p given dev id %llu\n", rbd_dev,
4330 (unsigned long long) rbd_dev->dev_id);
4334 * Remove an rbd_dev from the global list, and record that its
4335 * identifier is no longer in use.
4337 static void rbd_dev_id_put(struct rbd_device *rbd_dev)
4339 struct list_head *tmp;
4340 int rbd_id = rbd_dev->dev_id;
4343 rbd_assert(rbd_id > 0);
4345 dout("rbd_dev %p released dev id %llu\n", rbd_dev,
4346 (unsigned long long) rbd_dev->dev_id);
4347 spin_lock(&rbd_dev_list_lock);
4348 list_del_init(&rbd_dev->node);
4351 * If the id being "put" is not the current maximum, there
4352 * is nothing special we need to do.
4354 if (rbd_id != atomic64_read(&rbd_dev_id_max)) {
4355 spin_unlock(&rbd_dev_list_lock);
4360 * We need to update the current maximum id. Search the
4361 * list to find out what it is. We're more likely to find
4362 * the maximum at the end, so search the list backward.
4365 list_for_each_prev(tmp, &rbd_dev_list) {
4366 struct rbd_device *rbd_dev;
4368 rbd_dev = list_entry(tmp, struct rbd_device, node);
4369 if (rbd_dev->dev_id > max_id)
4370 max_id = rbd_dev->dev_id;
4372 spin_unlock(&rbd_dev_list_lock);
4375 * The max id could have been updated by rbd_dev_id_get(), in
4376 * which case it now accurately reflects the new maximum.
4377 * Be careful not to overwrite the maximum value in that
4380 atomic64_cmpxchg(&rbd_dev_id_max, rbd_id, max_id);
4381 dout(" max dev id has been reset\n");
4385 * Skips over white space at *buf, and updates *buf to point to the
4386 * first found non-space character (if any). Returns the length of
4387 * the token (string of non-white space characters) found. Note
4388 * that *buf must be terminated with '\0'.
4390 static inline size_t next_token(const char **buf)
4393 * These are the characters that produce nonzero for
4394 * isspace() in the "C" and "POSIX" locales.
4396 const char *spaces = " \f\n\r\t\v";
4398 *buf += strspn(*buf, spaces); /* Find start of token */
4400 return strcspn(*buf, spaces); /* Return token length */
4404 * Finds the next token in *buf, and if the provided token buffer is
4405 * big enough, copies the found token into it. The result, if
4406 * copied, is guaranteed to be terminated with '\0'. Note that *buf
4407 * must be terminated with '\0' on entry.
4409 * Returns the length of the token found (not including the '\0').
4410 * Return value will be 0 if no token is found, and it will be >=
4411 * token_size if the token would not fit.
4413 * The *buf pointer will be updated to point beyond the end of the
4414 * found token. Note that this occurs even if the token buffer is
4415 * too small to hold it.
4417 static inline size_t copy_token(const char **buf,
4423 len = next_token(buf);
4424 if (len < token_size) {
4425 memcpy(token, *buf, len);
4426 *(token + len) = '\0';
4434 * Finds the next token in *buf, dynamically allocates a buffer big
4435 * enough to hold a copy of it, and copies the token into the new
4436 * buffer. The copy is guaranteed to be terminated with '\0'. Note
4437 * that a duplicate buffer is created even for a zero-length token.
4439 * Returns a pointer to the newly-allocated duplicate, or a null
4440 * pointer if memory for the duplicate was not available. If
4441 * the lenp argument is a non-null pointer, the length of the token
4442 * (not including the '\0') is returned in *lenp.
4444 * If successful, the *buf pointer will be updated to point beyond
4445 * the end of the found token.
4447 * Note: uses GFP_KERNEL for allocation.
4449 static inline char *dup_token(const char **buf, size_t *lenp)
4454 len = next_token(buf);
4455 dup = kmemdup(*buf, len + 1, GFP_KERNEL);
4458 *(dup + len) = '\0';
4468 * Parse the options provided for an "rbd add" (i.e., rbd image
4469 * mapping) request. These arrive via a write to /sys/bus/rbd/add,
4470 * and the data written is passed here via a NUL-terminated buffer.
4471 * Returns 0 if successful or an error code otherwise.
4473 * The information extracted from these options is recorded in
4474 * the other parameters which return dynamically-allocated
4477 * The address of a pointer that will refer to a ceph options
4478 * structure. Caller must release the returned pointer using
4479 * ceph_destroy_options() when it is no longer needed.
4481 * Address of an rbd options pointer. Fully initialized by
4482 * this function; caller must release with kfree().
4484 * Address of an rbd image specification pointer. Fully
4485 * initialized by this function based on parsed options.
4486 * Caller must release with rbd_spec_put().
4488 * The options passed take this form:
4489 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
4492 * A comma-separated list of one or more monitor addresses.
4493 * A monitor address is an ip address, optionally followed
4494 * by a port number (separated by a colon).
4495 * I.e.: ip1[:port1][,ip2[:port2]...]
4497 * A comma-separated list of ceph and/or rbd options.
4499 * The name of the rados pool containing the rbd image.
4501 * The name of the image in that pool to map.
4503 * An optional snapshot id. If provided, the mapping will
4504 * present data from the image at the time that snapshot was
4505 * created. The image head is used if no snapshot id is
4506 * provided. Snapshot mappings are always read-only.
4508 static int rbd_add_parse_args(const char *buf,
4509 struct ceph_options **ceph_opts,
4510 struct rbd_options **opts,
4511 struct rbd_spec **rbd_spec)
4515 const char *mon_addrs;
4517 size_t mon_addrs_size;
4518 struct rbd_spec *spec = NULL;
4519 struct rbd_options *rbd_opts = NULL;
4520 struct ceph_options *copts;
4523 /* The first four tokens are required */
4525 len = next_token(&buf);
4527 rbd_warn(NULL, "no monitor address(es) provided");
4531 mon_addrs_size = len + 1;
4535 options = dup_token(&buf, NULL);
4539 rbd_warn(NULL, "no options provided");
4543 spec = rbd_spec_alloc();
4547 spec->pool_name = dup_token(&buf, NULL);
4548 if (!spec->pool_name)
4550 if (!*spec->pool_name) {
4551 rbd_warn(NULL, "no pool name provided");
4555 spec->image_name = dup_token(&buf, NULL);
4556 if (!spec->image_name)
4558 if (!*spec->image_name) {
4559 rbd_warn(NULL, "no image name provided");
4564 * Snapshot name is optional; default is to use "-"
4565 * (indicating the head/no snapshot).
4567 len = next_token(&buf);
4569 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
4570 len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
4571 } else if (len > RBD_MAX_SNAP_NAME_LEN) {
4572 ret = -ENAMETOOLONG;
4575 snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
4578 *(snap_name + len) = '\0';
4579 spec->snap_name = snap_name;
4581 /* Initialize all rbd options to the defaults */
4583 rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL);
4587 rbd_opts->read_only = RBD_READ_ONLY_DEFAULT;
4589 copts = ceph_parse_options(options, mon_addrs,
4590 mon_addrs + mon_addrs_size - 1,
4591 parse_rbd_opts_token, rbd_opts);
4592 if (IS_ERR(copts)) {
4593 ret = PTR_ERR(copts);
4614 * An rbd format 2 image has a unique identifier, distinct from the
4615 * name given to it by the user. Internally, that identifier is
4616 * what's used to specify the names of objects related to the image.
4618 * A special "rbd id" object is used to map an rbd image name to its
4619 * id. If that object doesn't exist, then there is no v2 rbd image
4620 * with the supplied name.
4622 * This function will record the given rbd_dev's image_id field if
4623 * it can be determined, and in that case will return 0. If any
4624 * errors occur a negative errno will be returned and the rbd_dev's
4625 * image_id field will be unchanged (and should be NULL).
4627 static int rbd_dev_image_id(struct rbd_device *rbd_dev)
4636 * When probing a parent image, the image id is already
4637 * known (and the image name likely is not). There's no
4638 * need to fetch the image id again in this case. We
4639 * do still need to set the image format though.
4641 if (rbd_dev->spec->image_id) {
4642 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;
4648 * First, see if the format 2 image id file exists, and if
4649 * so, get the image's persistent id from it.
4651 size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name);
4652 object_name = kmalloc(size, GFP_NOIO);
4655 sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name);
4656 dout("rbd id object name is %s\n", object_name);
4658 /* Response will be an encoded string, which includes a length */
4660 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
4661 response = kzalloc(size, GFP_NOIO);
4667 /* If it doesn't exist we'll assume it's a format 1 image */
4669 ret = rbd_obj_method_sync(rbd_dev, object_name,
4670 "rbd", "get_id", NULL, 0,
4671 response, RBD_IMAGE_ID_LEN_MAX);
4672 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4673 if (ret == -ENOENT) {
4674 image_id = kstrdup("", GFP_KERNEL);
4675 ret = image_id ? 0 : -ENOMEM;
4677 rbd_dev->image_format = 1;
4678 } else if (ret > sizeof (__le32)) {
4681 image_id = ceph_extract_encoded_string(&p, p + ret,
4683 ret = IS_ERR(image_id) ? PTR_ERR(image_id) : 0;
4685 rbd_dev->image_format = 2;
4691 rbd_dev->spec->image_id = image_id;
4692 dout("image_id is %s\n", image_id);
4702 * Undo whatever state changes are made by v1 or v2 header info
4705 static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
4707 struct rbd_image_header *header;
4709 /* Drop parent reference unless it's already been done (or none) */
4711 if (rbd_dev->parent_overlap)
4712 rbd_dev_parent_put(rbd_dev);
4714 /* Free dynamic fields from the header, then zero it out */
4716 header = &rbd_dev->header;
4717 ceph_put_snap_context(header->snapc);
4718 kfree(header->snap_sizes);
4719 kfree(header->snap_names);
4720 kfree(header->object_prefix);
4721 memset(header, 0, sizeof (*header));
4724 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev)
4728 ret = rbd_dev_v2_object_prefix(rbd_dev);
4733 * Get the and check features for the image. Currently the
4734 * features are assumed to never change.
4736 ret = rbd_dev_v2_features(rbd_dev);
4740 /* If the image supports fancy striping, get its parameters */
4742 if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
4743 ret = rbd_dev_v2_striping_info(rbd_dev);
4747 /* No support for crypto and compression type format 2 images */
4751 rbd_dev->header.features = 0;
4752 kfree(rbd_dev->header.object_prefix);
4753 rbd_dev->header.object_prefix = NULL;
4758 static int rbd_dev_probe_parent(struct rbd_device *rbd_dev)
4760 struct rbd_device *parent = NULL;
4761 struct rbd_spec *parent_spec;
4762 struct rbd_client *rbdc;
4765 if (!rbd_dev->parent_spec)
4768 * We need to pass a reference to the client and the parent
4769 * spec when creating the parent rbd_dev. Images related by
4770 * parent/child relationships always share both.
4772 parent_spec = rbd_spec_get(rbd_dev->parent_spec);
4773 rbdc = __rbd_get_client(rbd_dev->rbd_client);
4776 parent = rbd_dev_create(rbdc, parent_spec);
4780 ret = rbd_dev_image_probe(parent, false);
4783 rbd_dev->parent = parent;
4784 atomic_set(&rbd_dev->parent_ref, 1);
4789 rbd_dev_unparent(rbd_dev);
4790 kfree(rbd_dev->header_name);
4791 rbd_dev_destroy(parent);
4793 rbd_put_client(rbdc);
4794 rbd_spec_put(parent_spec);
4800 static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
4804 /* generate unique id: find highest unique id, add one */
4805 rbd_dev_id_get(rbd_dev);
4807 /* Fill in the device name, now that we have its id. */
4808 BUILD_BUG_ON(DEV_NAME_LEN
4809 < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
4810 sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id);
4812 /* Get our block major device number. */
4814 ret = register_blkdev(0, rbd_dev->name);
4817 rbd_dev->major = ret;
4819 /* Set up the blkdev mapping. */
4821 ret = rbd_init_disk(rbd_dev);
4823 goto err_out_blkdev;
4825 ret = rbd_dev_mapping_set(rbd_dev);
4828 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
4830 ret = rbd_bus_add_dev(rbd_dev);
4832 goto err_out_mapping;
4834 /* Everything's ready. Announce the disk to the world. */
4836 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
4837 add_disk(rbd_dev->disk);
4839 pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name,
4840 (unsigned long long) rbd_dev->mapping.size);
4845 rbd_dev_mapping_clear(rbd_dev);
4847 rbd_free_disk(rbd_dev);
4849 unregister_blkdev(rbd_dev->major, rbd_dev->name);
4851 rbd_dev_id_put(rbd_dev);
4852 rbd_dev_mapping_clear(rbd_dev);
4857 static int rbd_dev_header_name(struct rbd_device *rbd_dev)
4859 struct rbd_spec *spec = rbd_dev->spec;
4862 /* Record the header object name for this rbd image. */
4864 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
4866 if (rbd_dev->image_format == 1)
4867 size = strlen(spec->image_name) + sizeof (RBD_SUFFIX);
4869 size = sizeof (RBD_HEADER_PREFIX) + strlen(spec->image_id);
4871 rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
4872 if (!rbd_dev->header_name)
4875 if (rbd_dev->image_format == 1)
4876 sprintf(rbd_dev->header_name, "%s%s",
4877 spec->image_name, RBD_SUFFIX);
4879 sprintf(rbd_dev->header_name, "%s%s",
4880 RBD_HEADER_PREFIX, spec->image_id);
4884 static void rbd_dev_image_release(struct rbd_device *rbd_dev)
4886 rbd_dev_unprobe(rbd_dev);
4887 kfree(rbd_dev->header_name);
4888 rbd_dev->header_name = NULL;
4889 rbd_dev->image_format = 0;
4890 kfree(rbd_dev->spec->image_id);
4891 rbd_dev->spec->image_id = NULL;
4893 rbd_dev_destroy(rbd_dev);
4897 * Probe for the existence of the header object for the given rbd
4898 * device. If this image is the one being mapped (i.e., not a
4899 * parent), initiate a watch on its header object before using that
4900 * object to get detailed information about the rbd image.
4902 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping)
4908 * Get the id from the image id object. Unless there's an
4909 * error, rbd_dev->spec->image_id will be filled in with
4910 * a dynamically-allocated string, and rbd_dev->image_format
4911 * will be set to either 1 or 2.
4913 ret = rbd_dev_image_id(rbd_dev);
4916 rbd_assert(rbd_dev->spec->image_id);
4917 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
4919 ret = rbd_dev_header_name(rbd_dev);
4921 goto err_out_format;
4924 ret = rbd_dev_header_watch_sync(rbd_dev, true);
4926 goto out_header_name;
4929 if (rbd_dev->image_format == 1)
4930 ret = rbd_dev_v1_header_info(rbd_dev);
4932 ret = rbd_dev_v2_header_info(rbd_dev);
4936 ret = rbd_dev_spec_update(rbd_dev);
4940 ret = rbd_dev_probe_parent(rbd_dev);
4944 dout("discovered format %u image, header name is %s\n",
4945 rbd_dev->image_format, rbd_dev->header_name);
4949 rbd_dev_unprobe(rbd_dev);
4952 tmp = rbd_dev_header_watch_sync(rbd_dev, false);
4954 rbd_warn(rbd_dev, "unable to tear down "
4955 "watch request (%d)\n", tmp);
4958 kfree(rbd_dev->header_name);
4959 rbd_dev->header_name = NULL;
4961 rbd_dev->image_format = 0;
4962 kfree(rbd_dev->spec->image_id);
4963 rbd_dev->spec->image_id = NULL;
4965 dout("probe failed, returning %d\n", ret);
4970 static ssize_t rbd_add(struct bus_type *bus,
4974 struct rbd_device *rbd_dev = NULL;
4975 struct ceph_options *ceph_opts = NULL;
4976 struct rbd_options *rbd_opts = NULL;
4977 struct rbd_spec *spec = NULL;
4978 struct rbd_client *rbdc;
4979 struct ceph_osd_client *osdc;
4983 if (!try_module_get(THIS_MODULE))
4986 /* parse add command */
4987 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
4989 goto err_out_module;
4990 read_only = rbd_opts->read_only;
4992 rbd_opts = NULL; /* done with this */
4994 rbdc = rbd_get_client(ceph_opts);
5001 osdc = &rbdc->client->osdc;
5002 rc = ceph_pg_poolid_by_name(osdc->osdmap, spec->pool_name);
5004 goto err_out_client;
5005 spec->pool_id = (u64)rc;
5007 /* The ceph file layout needs to fit pool id in 32 bits */
5009 if (spec->pool_id > (u64)U32_MAX) {
5010 rbd_warn(NULL, "pool id too large (%llu > %u)\n",
5011 (unsigned long long)spec->pool_id, U32_MAX);
5013 goto err_out_client;
5016 rbd_dev = rbd_dev_create(rbdc, spec);
5018 goto err_out_client;
5019 rbdc = NULL; /* rbd_dev now owns this */
5020 spec = NULL; /* rbd_dev now owns this */
5022 rc = rbd_dev_image_probe(rbd_dev, true);
5024 goto err_out_rbd_dev;
5026 /* If we are mapping a snapshot it must be marked read-only */
5028 if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
5030 rbd_dev->mapping.read_only = read_only;
5032 rc = rbd_dev_device_setup(rbd_dev);
5034 rbd_dev_image_release(rbd_dev);
5035 goto err_out_module;
5041 rbd_dev_destroy(rbd_dev);
5043 rbd_put_client(rbdc);
5047 module_put(THIS_MODULE);
5049 dout("Error adding device %s\n", buf);
5054 static struct rbd_device *__rbd_get_dev(unsigned long dev_id)
5056 struct list_head *tmp;
5057 struct rbd_device *rbd_dev;
5059 spin_lock(&rbd_dev_list_lock);
5060 list_for_each(tmp, &rbd_dev_list) {
5061 rbd_dev = list_entry(tmp, struct rbd_device, node);
5062 if (rbd_dev->dev_id == dev_id) {
5063 spin_unlock(&rbd_dev_list_lock);
5067 spin_unlock(&rbd_dev_list_lock);
5071 static void rbd_dev_device_release(struct device *dev)
5073 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5075 rbd_free_disk(rbd_dev);
5076 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
5077 rbd_dev_mapping_clear(rbd_dev);
5078 unregister_blkdev(rbd_dev->major, rbd_dev->name);
5080 rbd_dev_id_put(rbd_dev);
5081 rbd_dev_mapping_clear(rbd_dev);
5084 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
5086 while (rbd_dev->parent) {
5087 struct rbd_device *first = rbd_dev;
5088 struct rbd_device *second = first->parent;
5089 struct rbd_device *third;
5092 * Follow to the parent with no grandparent and
5095 while (second && (third = second->parent)) {
5100 rbd_dev_image_release(second);
5101 first->parent = NULL;
5102 first->parent_overlap = 0;
5104 rbd_assert(first->parent_spec);
5105 rbd_spec_put(first->parent_spec);
5106 first->parent_spec = NULL;
5110 static ssize_t rbd_remove(struct bus_type *bus,
5114 struct rbd_device *rbd_dev = NULL;
5119 ret = strict_strtoul(buf, 10, &ul);
5123 /* convert to int; abort if we lost anything in the conversion */
5124 target_id = (int) ul;
5125 if (target_id != ul)
5128 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
5130 rbd_dev = __rbd_get_dev(target_id);
5136 spin_lock_irq(&rbd_dev->lock);
5137 if (rbd_dev->open_count)
5140 set_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags);
5141 spin_unlock_irq(&rbd_dev->lock);
5144 rbd_bus_del_dev(rbd_dev);
5145 ret = rbd_dev_header_watch_sync(rbd_dev, false);
5147 rbd_warn(rbd_dev, "failed to cancel watch event (%d)\n", ret);
5148 rbd_dev_image_release(rbd_dev);
5149 module_put(THIS_MODULE);
5152 mutex_unlock(&ctl_mutex);
5158 * create control files in sysfs
5161 static int rbd_sysfs_init(void)
5165 ret = device_register(&rbd_root_dev);
5169 ret = bus_register(&rbd_bus_type);
5171 device_unregister(&rbd_root_dev);
5176 static void rbd_sysfs_cleanup(void)
5178 bus_unregister(&rbd_bus_type);
5179 device_unregister(&rbd_root_dev);
5182 static int rbd_slab_init(void)
5184 rbd_assert(!rbd_img_request_cache);
5185 rbd_img_request_cache = kmem_cache_create("rbd_img_request",
5186 sizeof (struct rbd_img_request),
5187 __alignof__(struct rbd_img_request),
5189 if (!rbd_img_request_cache)
5192 rbd_assert(!rbd_obj_request_cache);
5193 rbd_obj_request_cache = kmem_cache_create("rbd_obj_request",
5194 sizeof (struct rbd_obj_request),
5195 __alignof__(struct rbd_obj_request),
5197 if (!rbd_obj_request_cache)
5200 rbd_assert(!rbd_segment_name_cache);
5201 rbd_segment_name_cache = kmem_cache_create("rbd_segment_name",
5202 MAX_OBJ_NAME_SIZE + 1, 1, 0, NULL);
5203 if (rbd_segment_name_cache)
5206 if (rbd_obj_request_cache) {
5207 kmem_cache_destroy(rbd_obj_request_cache);
5208 rbd_obj_request_cache = NULL;
5211 kmem_cache_destroy(rbd_img_request_cache);
5212 rbd_img_request_cache = NULL;
5217 static void rbd_slab_exit(void)
5219 rbd_assert(rbd_segment_name_cache);
5220 kmem_cache_destroy(rbd_segment_name_cache);
5221 rbd_segment_name_cache = NULL;
5223 rbd_assert(rbd_obj_request_cache);
5224 kmem_cache_destroy(rbd_obj_request_cache);
5225 rbd_obj_request_cache = NULL;
5227 rbd_assert(rbd_img_request_cache);
5228 kmem_cache_destroy(rbd_img_request_cache);
5229 rbd_img_request_cache = NULL;
5232 static int __init rbd_init(void)
5236 if (!libceph_compatible(NULL)) {
5237 rbd_warn(NULL, "libceph incompatibility (quitting)");
5241 rc = rbd_slab_init();
5244 rc = rbd_sysfs_init();
5248 pr_info("loaded " RBD_DRV_NAME_LONG "\n");
5253 static void __exit rbd_exit(void)
5255 rbd_sysfs_cleanup();
5259 module_init(rbd_init);
5260 module_exit(rbd_exit);
5262 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
5263 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
5264 MODULE_DESCRIPTION("rados block device");
5266 /* following authorship retained from original osdblk.c */
5267 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
5269 MODULE_LICENSE("GPL");