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,
940 const char *snap_name;
942 which = rbd_dev_snap_index(rbd_dev, snap_id);
943 if (which == BAD_SNAP_INDEX)
944 return ERR_PTR(-ENOENT);
946 snap_name = _rbd_dev_v1_snap_name(rbd_dev, which);
947 return snap_name ? snap_name : ERR_PTR(-ENOMEM);
950 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
952 if (snap_id == CEPH_NOSNAP)
953 return RBD_SNAP_HEAD_NAME;
955 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
956 if (rbd_dev->image_format == 1)
957 return rbd_dev_v1_snap_name(rbd_dev, snap_id);
959 return rbd_dev_v2_snap_name(rbd_dev, snap_id);
962 static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
965 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
966 if (snap_id == CEPH_NOSNAP) {
967 *snap_size = rbd_dev->header.image_size;
968 } else if (rbd_dev->image_format == 1) {
971 which = rbd_dev_snap_index(rbd_dev, snap_id);
972 if (which == BAD_SNAP_INDEX)
975 *snap_size = rbd_dev->header.snap_sizes[which];
980 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
989 static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
992 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
993 if (snap_id == CEPH_NOSNAP) {
994 *snap_features = rbd_dev->header.features;
995 } else if (rbd_dev->image_format == 1) {
996 *snap_features = 0; /* No features for format 1 */
1001 ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features);
1005 *snap_features = features;
1010 static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
1012 u64 snap_id = rbd_dev->spec->snap_id;
1017 ret = rbd_snap_size(rbd_dev, snap_id, &size);
1020 ret = rbd_snap_features(rbd_dev, snap_id, &features);
1024 rbd_dev->mapping.size = size;
1025 rbd_dev->mapping.features = features;
1030 static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
1032 rbd_dev->mapping.size = 0;
1033 rbd_dev->mapping.features = 0;
1036 static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset)
1043 name = kmem_cache_alloc(rbd_segment_name_cache, GFP_NOIO);
1046 segment = offset >> rbd_dev->header.obj_order;
1047 name_format = "%s.%012llx";
1048 if (rbd_dev->image_format == 2)
1049 name_format = "%s.%016llx";
1050 ret = snprintf(name, MAX_OBJ_NAME_SIZE + 1, name_format,
1051 rbd_dev->header.object_prefix, segment);
1052 if (ret < 0 || ret > MAX_OBJ_NAME_SIZE) {
1053 pr_err("error formatting segment name for #%llu (%d)\n",
1062 static void rbd_segment_name_free(const char *name)
1064 /* The explicit cast here is needed to drop the const qualifier */
1066 kmem_cache_free(rbd_segment_name_cache, (void *)name);
1069 static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset)
1071 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1073 return offset & (segment_size - 1);
1076 static u64 rbd_segment_length(struct rbd_device *rbd_dev,
1077 u64 offset, u64 length)
1079 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1081 offset &= segment_size - 1;
1083 rbd_assert(length <= U64_MAX - offset);
1084 if (offset + length > segment_size)
1085 length = segment_size - offset;
1091 * returns the size of an object in the image
1093 static u64 rbd_obj_bytes(struct rbd_image_header *header)
1095 return 1 << header->obj_order;
1102 static void bio_chain_put(struct bio *chain)
1108 chain = chain->bi_next;
1114 * zeros a bio chain, starting at specific offset
1116 static void zero_bio_chain(struct bio *chain, int start_ofs)
1119 unsigned long flags;
1125 bio_for_each_segment(bv, chain, i) {
1126 if (pos + bv->bv_len > start_ofs) {
1127 int remainder = max(start_ofs - pos, 0);
1128 buf = bvec_kmap_irq(bv, &flags);
1129 memset(buf + remainder, 0,
1130 bv->bv_len - remainder);
1131 flush_dcache_page(bv->bv_page);
1132 bvec_kunmap_irq(buf, &flags);
1137 chain = chain->bi_next;
1142 * similar to zero_bio_chain(), zeros data defined by a page array,
1143 * starting at the given byte offset from the start of the array and
1144 * continuing up to the given end offset. The pages array is
1145 * assumed to be big enough to hold all bytes up to the end.
1147 static void zero_pages(struct page **pages, u64 offset, u64 end)
1149 struct page **page = &pages[offset >> PAGE_SHIFT];
1151 rbd_assert(end > offset);
1152 rbd_assert(end - offset <= (u64)SIZE_MAX);
1153 while (offset < end) {
1156 unsigned long flags;
1159 page_offset = (size_t)(offset & ~PAGE_MASK);
1160 length = min(PAGE_SIZE - page_offset, (size_t)(end - offset));
1161 local_irq_save(flags);
1162 kaddr = kmap_atomic(*page);
1163 memset(kaddr + page_offset, 0, length);
1164 flush_dcache_page(*page);
1165 kunmap_atomic(kaddr);
1166 local_irq_restore(flags);
1174 * Clone a portion of a bio, starting at the given byte offset
1175 * and continuing for the number of bytes indicated.
1177 static struct bio *bio_clone_range(struct bio *bio_src,
1178 unsigned int offset,
1186 unsigned short end_idx;
1187 unsigned short vcnt;
1190 /* Handle the easy case for the caller */
1192 if (!offset && len == bio_src->bi_size)
1193 return bio_clone(bio_src, gfpmask);
1195 if (WARN_ON_ONCE(!len))
1197 if (WARN_ON_ONCE(len > bio_src->bi_size))
1199 if (WARN_ON_ONCE(offset > bio_src->bi_size - len))
1202 /* Find first affected segment... */
1205 bio_for_each_segment(bv, bio_src, idx) {
1206 if (resid < bv->bv_len)
1208 resid -= bv->bv_len;
1212 /* ...and the last affected segment */
1215 __bio_for_each_segment(bv, bio_src, end_idx, idx) {
1216 if (resid <= bv->bv_len)
1218 resid -= bv->bv_len;
1220 vcnt = end_idx - idx + 1;
1222 /* Build the clone */
1224 bio = bio_alloc(gfpmask, (unsigned int) vcnt);
1226 return NULL; /* ENOMEM */
1228 bio->bi_bdev = bio_src->bi_bdev;
1229 bio->bi_sector = bio_src->bi_sector + (offset >> SECTOR_SHIFT);
1230 bio->bi_rw = bio_src->bi_rw;
1231 bio->bi_flags |= 1 << BIO_CLONED;
1234 * Copy over our part of the bio_vec, then update the first
1235 * and last (or only) entries.
1237 memcpy(&bio->bi_io_vec[0], &bio_src->bi_io_vec[idx],
1238 vcnt * sizeof (struct bio_vec));
1239 bio->bi_io_vec[0].bv_offset += voff;
1241 bio->bi_io_vec[0].bv_len -= voff;
1242 bio->bi_io_vec[vcnt - 1].bv_len = resid;
1244 bio->bi_io_vec[0].bv_len = len;
1247 bio->bi_vcnt = vcnt;
1255 * Clone a portion of a bio chain, starting at the given byte offset
1256 * into the first bio in the source chain and continuing for the
1257 * number of bytes indicated. The result is another bio chain of
1258 * exactly the given length, or a null pointer on error.
1260 * The bio_src and offset parameters are both in-out. On entry they
1261 * refer to the first source bio and the offset into that bio where
1262 * the start of data to be cloned is located.
1264 * On return, bio_src is updated to refer to the bio in the source
1265 * chain that contains first un-cloned byte, and *offset will
1266 * contain the offset of that byte within that bio.
1268 static struct bio *bio_chain_clone_range(struct bio **bio_src,
1269 unsigned int *offset,
1273 struct bio *bi = *bio_src;
1274 unsigned int off = *offset;
1275 struct bio *chain = NULL;
1278 /* Build up a chain of clone bios up to the limit */
1280 if (!bi || off >= bi->bi_size || !len)
1281 return NULL; /* Nothing to clone */
1285 unsigned int bi_size;
1289 rbd_warn(NULL, "bio_chain exhausted with %u left", len);
1290 goto out_err; /* EINVAL; ran out of bio's */
1292 bi_size = min_t(unsigned int, bi->bi_size - off, len);
1293 bio = bio_clone_range(bi, off, bi_size, gfpmask);
1295 goto out_err; /* ENOMEM */
1298 end = &bio->bi_next;
1301 if (off == bi->bi_size) {
1312 bio_chain_put(chain);
1318 * The default/initial value for all object request flags is 0. For
1319 * each flag, once its value is set to 1 it is never reset to 0
1322 static void obj_request_img_data_set(struct rbd_obj_request *obj_request)
1324 if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) {
1325 struct rbd_device *rbd_dev;
1327 rbd_dev = obj_request->img_request->rbd_dev;
1328 rbd_warn(rbd_dev, "obj_request %p already marked img_data\n",
1333 static bool obj_request_img_data_test(struct rbd_obj_request *obj_request)
1336 return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0;
1339 static void obj_request_done_set(struct rbd_obj_request *obj_request)
1341 if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) {
1342 struct rbd_device *rbd_dev = NULL;
1344 if (obj_request_img_data_test(obj_request))
1345 rbd_dev = obj_request->img_request->rbd_dev;
1346 rbd_warn(rbd_dev, "obj_request %p already marked done\n",
1351 static bool obj_request_done_test(struct rbd_obj_request *obj_request)
1354 return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0;
1358 * This sets the KNOWN flag after (possibly) setting the EXISTS
1359 * flag. The latter is set based on the "exists" value provided.
1361 * Note that for our purposes once an object exists it never goes
1362 * away again. It's possible that the response from two existence
1363 * checks are separated by the creation of the target object, and
1364 * the first ("doesn't exist") response arrives *after* the second
1365 * ("does exist"). In that case we ignore the second one.
1367 static void obj_request_existence_set(struct rbd_obj_request *obj_request,
1371 set_bit(OBJ_REQ_EXISTS, &obj_request->flags);
1372 set_bit(OBJ_REQ_KNOWN, &obj_request->flags);
1376 static bool obj_request_known_test(struct rbd_obj_request *obj_request)
1379 return test_bit(OBJ_REQ_KNOWN, &obj_request->flags) != 0;
1382 static bool obj_request_exists_test(struct rbd_obj_request *obj_request)
1385 return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0;
1388 static bool obj_request_overlaps_parent(struct rbd_obj_request *obj_request)
1390 struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev;
1392 return obj_request->img_offset <
1393 round_up(rbd_dev->parent_overlap, rbd_obj_bytes(&rbd_dev->header));
1396 static void rbd_obj_request_get(struct rbd_obj_request *obj_request)
1398 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1399 atomic_read(&obj_request->kref.refcount));
1400 kref_get(&obj_request->kref);
1403 static void rbd_obj_request_destroy(struct kref *kref);
1404 static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
1406 rbd_assert(obj_request != NULL);
1407 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1408 atomic_read(&obj_request->kref.refcount));
1409 kref_put(&obj_request->kref, rbd_obj_request_destroy);
1412 static void rbd_img_request_get(struct rbd_img_request *img_request)
1414 dout("%s: img %p (was %d)\n", __func__, img_request,
1415 atomic_read(&img_request->kref.refcount));
1416 kref_get(&img_request->kref);
1419 static bool img_request_child_test(struct rbd_img_request *img_request);
1420 static void rbd_parent_request_destroy(struct kref *kref);
1421 static void rbd_img_request_destroy(struct kref *kref);
1422 static void rbd_img_request_put(struct rbd_img_request *img_request)
1424 rbd_assert(img_request != NULL);
1425 dout("%s: img %p (was %d)\n", __func__, img_request,
1426 atomic_read(&img_request->kref.refcount));
1427 if (img_request_child_test(img_request))
1428 kref_put(&img_request->kref, rbd_parent_request_destroy);
1430 kref_put(&img_request->kref, rbd_img_request_destroy);
1433 static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
1434 struct rbd_obj_request *obj_request)
1436 rbd_assert(obj_request->img_request == NULL);
1438 /* Image request now owns object's original reference */
1439 obj_request->img_request = img_request;
1440 obj_request->which = img_request->obj_request_count;
1441 rbd_assert(!obj_request_img_data_test(obj_request));
1442 obj_request_img_data_set(obj_request);
1443 rbd_assert(obj_request->which != BAD_WHICH);
1444 img_request->obj_request_count++;
1445 list_add_tail(&obj_request->links, &img_request->obj_requests);
1446 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1447 obj_request->which);
1450 static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
1451 struct rbd_obj_request *obj_request)
1453 rbd_assert(obj_request->which != BAD_WHICH);
1455 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1456 obj_request->which);
1457 list_del(&obj_request->links);
1458 rbd_assert(img_request->obj_request_count > 0);
1459 img_request->obj_request_count--;
1460 rbd_assert(obj_request->which == img_request->obj_request_count);
1461 obj_request->which = BAD_WHICH;
1462 rbd_assert(obj_request_img_data_test(obj_request));
1463 rbd_assert(obj_request->img_request == img_request);
1464 obj_request->img_request = NULL;
1465 obj_request->callback = NULL;
1466 rbd_obj_request_put(obj_request);
1469 static bool obj_request_type_valid(enum obj_request_type type)
1472 case OBJ_REQUEST_NODATA:
1473 case OBJ_REQUEST_BIO:
1474 case OBJ_REQUEST_PAGES:
1481 static int rbd_obj_request_submit(struct ceph_osd_client *osdc,
1482 struct rbd_obj_request *obj_request)
1484 dout("%s: osdc %p obj %p\n", __func__, osdc, obj_request);
1486 return ceph_osdc_start_request(osdc, obj_request->osd_req, false);
1489 static void rbd_img_request_complete(struct rbd_img_request *img_request)
1492 dout("%s: img %p\n", __func__, img_request);
1495 * If no error occurred, compute the aggregate transfer
1496 * count for the image request. We could instead use
1497 * atomic64_cmpxchg() to update it as each object request
1498 * completes; not clear which way is better off hand.
1500 if (!img_request->result) {
1501 struct rbd_obj_request *obj_request;
1504 for_each_obj_request(img_request, obj_request)
1505 xferred += obj_request->xferred;
1506 img_request->xferred = xferred;
1509 if (img_request->callback)
1510 img_request->callback(img_request);
1512 rbd_img_request_put(img_request);
1515 /* Caller is responsible for rbd_obj_request_destroy(obj_request) */
1517 static int rbd_obj_request_wait(struct rbd_obj_request *obj_request)
1519 dout("%s: obj %p\n", __func__, obj_request);
1521 return wait_for_completion_interruptible(&obj_request->completion);
1525 * The default/initial value for all image request flags is 0. Each
1526 * is conditionally set to 1 at image request initialization time
1527 * and currently never change thereafter.
1529 static void img_request_write_set(struct rbd_img_request *img_request)
1531 set_bit(IMG_REQ_WRITE, &img_request->flags);
1535 static bool img_request_write_test(struct rbd_img_request *img_request)
1538 return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0;
1541 static void img_request_child_set(struct rbd_img_request *img_request)
1543 set_bit(IMG_REQ_CHILD, &img_request->flags);
1547 static void img_request_child_clear(struct rbd_img_request *img_request)
1549 clear_bit(IMG_REQ_CHILD, &img_request->flags);
1553 static bool img_request_child_test(struct rbd_img_request *img_request)
1556 return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0;
1559 static void img_request_layered_set(struct rbd_img_request *img_request)
1561 set_bit(IMG_REQ_LAYERED, &img_request->flags);
1565 static void img_request_layered_clear(struct rbd_img_request *img_request)
1567 clear_bit(IMG_REQ_LAYERED, &img_request->flags);
1571 static bool img_request_layered_test(struct rbd_img_request *img_request)
1574 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
1578 rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
1580 u64 xferred = obj_request->xferred;
1581 u64 length = obj_request->length;
1583 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1584 obj_request, obj_request->img_request, obj_request->result,
1587 * ENOENT means a hole in the image. We zero-fill the entire
1588 * length of the request. A short read also implies zero-fill
1589 * to the end of the request. An error requires the whole
1590 * length of the request to be reported finished with an error
1591 * to the block layer. In each case we update the xferred
1592 * count to indicate the whole request was satisfied.
1594 rbd_assert(obj_request->type != OBJ_REQUEST_NODATA);
1595 if (obj_request->result == -ENOENT) {
1596 if (obj_request->type == OBJ_REQUEST_BIO)
1597 zero_bio_chain(obj_request->bio_list, 0);
1599 zero_pages(obj_request->pages, 0, length);
1600 obj_request->result = 0;
1601 } else if (xferred < length && !obj_request->result) {
1602 if (obj_request->type == OBJ_REQUEST_BIO)
1603 zero_bio_chain(obj_request->bio_list, xferred);
1605 zero_pages(obj_request->pages, xferred, length);
1607 obj_request->xferred = length;
1608 obj_request_done_set(obj_request);
1611 static void rbd_obj_request_complete(struct rbd_obj_request *obj_request)
1613 dout("%s: obj %p cb %p\n", __func__, obj_request,
1614 obj_request->callback);
1615 if (obj_request->callback)
1616 obj_request->callback(obj_request);
1618 complete_all(&obj_request->completion);
1621 static void rbd_osd_trivial_callback(struct rbd_obj_request *obj_request)
1623 dout("%s: obj %p\n", __func__, obj_request);
1624 obj_request_done_set(obj_request);
1627 static void rbd_osd_read_callback(struct rbd_obj_request *obj_request)
1629 struct rbd_img_request *img_request = NULL;
1630 struct rbd_device *rbd_dev = NULL;
1631 bool layered = false;
1633 if (obj_request_img_data_test(obj_request)) {
1634 img_request = obj_request->img_request;
1635 layered = img_request && img_request_layered_test(img_request);
1636 rbd_dev = img_request->rbd_dev;
1639 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1640 obj_request, img_request, obj_request->result,
1641 obj_request->xferred, obj_request->length);
1642 if (layered && obj_request->result == -ENOENT &&
1643 obj_request->img_offset < rbd_dev->parent_overlap)
1644 rbd_img_parent_read(obj_request);
1645 else if (img_request)
1646 rbd_img_obj_request_read_callback(obj_request);
1648 obj_request_done_set(obj_request);
1651 static void rbd_osd_write_callback(struct rbd_obj_request *obj_request)
1653 dout("%s: obj %p result %d %llu\n", __func__, obj_request,
1654 obj_request->result, obj_request->length);
1656 * There is no such thing as a successful short write. Set
1657 * it to our originally-requested length.
1659 obj_request->xferred = obj_request->length;
1660 obj_request_done_set(obj_request);
1664 * For a simple stat call there's nothing to do. We'll do more if
1665 * this is part of a write sequence for a layered image.
1667 static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request)
1669 dout("%s: obj %p\n", __func__, obj_request);
1670 obj_request_done_set(obj_request);
1673 static void rbd_osd_req_callback(struct ceph_osd_request *osd_req,
1674 struct ceph_msg *msg)
1676 struct rbd_obj_request *obj_request = osd_req->r_priv;
1679 dout("%s: osd_req %p msg %p\n", __func__, osd_req, msg);
1680 rbd_assert(osd_req == obj_request->osd_req);
1681 if (obj_request_img_data_test(obj_request)) {
1682 rbd_assert(obj_request->img_request);
1683 rbd_assert(obj_request->which != BAD_WHICH);
1685 rbd_assert(obj_request->which == BAD_WHICH);
1688 if (osd_req->r_result < 0)
1689 obj_request->result = osd_req->r_result;
1691 BUG_ON(osd_req->r_num_ops > 2);
1694 * We support a 64-bit length, but ultimately it has to be
1695 * passed to blk_end_request(), which takes an unsigned int.
1697 obj_request->xferred = osd_req->r_reply_op_len[0];
1698 rbd_assert(obj_request->xferred < (u64)UINT_MAX);
1699 opcode = osd_req->r_ops[0].op;
1701 case CEPH_OSD_OP_READ:
1702 rbd_osd_read_callback(obj_request);
1704 case CEPH_OSD_OP_WRITE:
1705 rbd_osd_write_callback(obj_request);
1707 case CEPH_OSD_OP_STAT:
1708 rbd_osd_stat_callback(obj_request);
1710 case CEPH_OSD_OP_CALL:
1711 case CEPH_OSD_OP_NOTIFY_ACK:
1712 case CEPH_OSD_OP_WATCH:
1713 rbd_osd_trivial_callback(obj_request);
1716 rbd_warn(NULL, "%s: unsupported op %hu\n",
1717 obj_request->object_name, (unsigned short) opcode);
1721 if (obj_request_done_test(obj_request))
1722 rbd_obj_request_complete(obj_request);
1725 static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request)
1727 struct rbd_img_request *img_request = obj_request->img_request;
1728 struct ceph_osd_request *osd_req = obj_request->osd_req;
1731 rbd_assert(osd_req != NULL);
1733 snap_id = img_request ? img_request->snap_id : CEPH_NOSNAP;
1734 ceph_osdc_build_request(osd_req, obj_request->offset,
1735 NULL, snap_id, NULL);
1738 static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request)
1740 struct rbd_img_request *img_request = obj_request->img_request;
1741 struct ceph_osd_request *osd_req = obj_request->osd_req;
1742 struct ceph_snap_context *snapc;
1743 struct timespec mtime = CURRENT_TIME;
1745 rbd_assert(osd_req != NULL);
1747 snapc = img_request ? img_request->snapc : NULL;
1748 ceph_osdc_build_request(osd_req, obj_request->offset,
1749 snapc, CEPH_NOSNAP, &mtime);
1752 static struct ceph_osd_request *rbd_osd_req_create(
1753 struct rbd_device *rbd_dev,
1755 struct rbd_obj_request *obj_request)
1757 struct ceph_snap_context *snapc = NULL;
1758 struct ceph_osd_client *osdc;
1759 struct ceph_osd_request *osd_req;
1761 if (obj_request_img_data_test(obj_request)) {
1762 struct rbd_img_request *img_request = obj_request->img_request;
1764 rbd_assert(write_request ==
1765 img_request_write_test(img_request));
1767 snapc = img_request->snapc;
1770 /* Allocate and initialize the request, for the single op */
1772 osdc = &rbd_dev->rbd_client->client->osdc;
1773 osd_req = ceph_osdc_alloc_request(osdc, snapc, 1, false, GFP_ATOMIC);
1775 return NULL; /* ENOMEM */
1778 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1780 osd_req->r_flags = CEPH_OSD_FLAG_READ;
1782 osd_req->r_callback = rbd_osd_req_callback;
1783 osd_req->r_priv = obj_request;
1785 osd_req->r_oid_len = strlen(obj_request->object_name);
1786 rbd_assert(osd_req->r_oid_len < sizeof (osd_req->r_oid));
1787 memcpy(osd_req->r_oid, obj_request->object_name, osd_req->r_oid_len);
1789 osd_req->r_file_layout = rbd_dev->layout; /* struct */
1795 * Create a copyup osd request based on the information in the
1796 * object request supplied. A copyup request has two osd ops,
1797 * a copyup method call, and a "normal" write request.
1799 static struct ceph_osd_request *
1800 rbd_osd_req_create_copyup(struct rbd_obj_request *obj_request)
1802 struct rbd_img_request *img_request;
1803 struct ceph_snap_context *snapc;
1804 struct rbd_device *rbd_dev;
1805 struct ceph_osd_client *osdc;
1806 struct ceph_osd_request *osd_req;
1808 rbd_assert(obj_request_img_data_test(obj_request));
1809 img_request = obj_request->img_request;
1810 rbd_assert(img_request);
1811 rbd_assert(img_request_write_test(img_request));
1813 /* Allocate and initialize the request, for the two ops */
1815 snapc = img_request->snapc;
1816 rbd_dev = img_request->rbd_dev;
1817 osdc = &rbd_dev->rbd_client->client->osdc;
1818 osd_req = ceph_osdc_alloc_request(osdc, snapc, 2, false, GFP_ATOMIC);
1820 return NULL; /* ENOMEM */
1822 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1823 osd_req->r_callback = rbd_osd_req_callback;
1824 osd_req->r_priv = obj_request;
1826 osd_req->r_oid_len = strlen(obj_request->object_name);
1827 rbd_assert(osd_req->r_oid_len < sizeof (osd_req->r_oid));
1828 memcpy(osd_req->r_oid, obj_request->object_name, osd_req->r_oid_len);
1830 osd_req->r_file_layout = rbd_dev->layout; /* struct */
1836 static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req)
1838 ceph_osdc_put_request(osd_req);
1841 /* object_name is assumed to be a non-null pointer and NUL-terminated */
1843 static struct rbd_obj_request *rbd_obj_request_create(const char *object_name,
1844 u64 offset, u64 length,
1845 enum obj_request_type type)
1847 struct rbd_obj_request *obj_request;
1851 rbd_assert(obj_request_type_valid(type));
1853 size = strlen(object_name) + 1;
1854 name = kmalloc(size, GFP_KERNEL);
1858 obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_KERNEL);
1864 obj_request->object_name = memcpy(name, object_name, size);
1865 obj_request->offset = offset;
1866 obj_request->length = length;
1867 obj_request->flags = 0;
1868 obj_request->which = BAD_WHICH;
1869 obj_request->type = type;
1870 INIT_LIST_HEAD(&obj_request->links);
1871 init_completion(&obj_request->completion);
1872 kref_init(&obj_request->kref);
1874 dout("%s: \"%s\" %llu/%llu %d -> obj %p\n", __func__, object_name,
1875 offset, length, (int)type, obj_request);
1880 static void rbd_obj_request_destroy(struct kref *kref)
1882 struct rbd_obj_request *obj_request;
1884 obj_request = container_of(kref, struct rbd_obj_request, kref);
1886 dout("%s: obj %p\n", __func__, obj_request);
1888 rbd_assert(obj_request->img_request == NULL);
1889 rbd_assert(obj_request->which == BAD_WHICH);
1891 if (obj_request->osd_req)
1892 rbd_osd_req_destroy(obj_request->osd_req);
1894 rbd_assert(obj_request_type_valid(obj_request->type));
1895 switch (obj_request->type) {
1896 case OBJ_REQUEST_NODATA:
1897 break; /* Nothing to do */
1898 case OBJ_REQUEST_BIO:
1899 if (obj_request->bio_list)
1900 bio_chain_put(obj_request->bio_list);
1902 case OBJ_REQUEST_PAGES:
1903 if (obj_request->pages)
1904 ceph_release_page_vector(obj_request->pages,
1905 obj_request->page_count);
1909 kfree(obj_request->object_name);
1910 obj_request->object_name = NULL;
1911 kmem_cache_free(rbd_obj_request_cache, obj_request);
1914 /* It's OK to call this for a device with no parent */
1916 static void rbd_spec_put(struct rbd_spec *spec);
1917 static void rbd_dev_unparent(struct rbd_device *rbd_dev)
1919 rbd_dev_remove_parent(rbd_dev);
1920 rbd_spec_put(rbd_dev->parent_spec);
1921 rbd_dev->parent_spec = NULL;
1922 rbd_dev->parent_overlap = 0;
1926 * Parent image reference counting is used to determine when an
1927 * image's parent fields can be safely torn down--after there are no
1928 * more in-flight requests to the parent image. When the last
1929 * reference is dropped, cleaning them up is safe.
1931 static void rbd_dev_parent_put(struct rbd_device *rbd_dev)
1935 if (!rbd_dev->parent_spec)
1938 counter = atomic_dec_return_safe(&rbd_dev->parent_ref);
1942 /* Last reference; clean up parent data structures */
1945 rbd_dev_unparent(rbd_dev);
1947 rbd_warn(rbd_dev, "parent reference underflow\n");
1951 * If an image has a non-zero parent overlap, get a reference to its
1954 * We must get the reference before checking for the overlap to
1955 * coordinate properly with zeroing the parent overlap in
1956 * rbd_dev_v2_parent_info() when an image gets flattened. We
1957 * drop it again if there is no overlap.
1959 * Returns true if the rbd device has a parent with a non-zero
1960 * overlap and a reference for it was successfully taken, or
1963 static bool rbd_dev_parent_get(struct rbd_device *rbd_dev)
1967 if (!rbd_dev->parent_spec)
1970 counter = atomic_inc_return_safe(&rbd_dev->parent_ref);
1971 if (counter > 0 && rbd_dev->parent_overlap)
1974 /* Image was flattened, but parent is not yet torn down */
1977 rbd_warn(rbd_dev, "parent reference overflow\n");
1983 * Caller is responsible for filling in the list of object requests
1984 * that comprises the image request, and the Linux request pointer
1985 * (if there is one).
1987 static struct rbd_img_request *rbd_img_request_create(
1988 struct rbd_device *rbd_dev,
1989 u64 offset, u64 length,
1992 struct rbd_img_request *img_request;
1994 img_request = kmem_cache_alloc(rbd_img_request_cache, GFP_ATOMIC);
1998 if (write_request) {
1999 down_read(&rbd_dev->header_rwsem);
2000 ceph_get_snap_context(rbd_dev->header.snapc);
2001 up_read(&rbd_dev->header_rwsem);
2004 img_request->rq = NULL;
2005 img_request->rbd_dev = rbd_dev;
2006 img_request->offset = offset;
2007 img_request->length = length;
2008 img_request->flags = 0;
2009 if (write_request) {
2010 img_request_write_set(img_request);
2011 img_request->snapc = rbd_dev->header.snapc;
2013 img_request->snap_id = rbd_dev->spec->snap_id;
2015 if (rbd_dev_parent_get(rbd_dev))
2016 img_request_layered_set(img_request);
2017 spin_lock_init(&img_request->completion_lock);
2018 img_request->next_completion = 0;
2019 img_request->callback = NULL;
2020 img_request->result = 0;
2021 img_request->obj_request_count = 0;
2022 INIT_LIST_HEAD(&img_request->obj_requests);
2023 kref_init(&img_request->kref);
2025 dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev,
2026 write_request ? "write" : "read", offset, length,
2032 static void rbd_img_request_destroy(struct kref *kref)
2034 struct rbd_img_request *img_request;
2035 struct rbd_obj_request *obj_request;
2036 struct rbd_obj_request *next_obj_request;
2038 img_request = container_of(kref, struct rbd_img_request, kref);
2040 dout("%s: img %p\n", __func__, img_request);
2042 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2043 rbd_img_obj_request_del(img_request, obj_request);
2044 rbd_assert(img_request->obj_request_count == 0);
2046 if (img_request_layered_test(img_request)) {
2047 img_request_layered_clear(img_request);
2048 rbd_dev_parent_put(img_request->rbd_dev);
2051 if (img_request_write_test(img_request))
2052 ceph_put_snap_context(img_request->snapc);
2054 kmem_cache_free(rbd_img_request_cache, img_request);
2057 static struct rbd_img_request *rbd_parent_request_create(
2058 struct rbd_obj_request *obj_request,
2059 u64 img_offset, u64 length)
2061 struct rbd_img_request *parent_request;
2062 struct rbd_device *rbd_dev;
2064 rbd_assert(obj_request->img_request);
2065 rbd_dev = obj_request->img_request->rbd_dev;
2067 parent_request = rbd_img_request_create(rbd_dev->parent,
2068 img_offset, length, false);
2069 if (!parent_request)
2072 img_request_child_set(parent_request);
2073 rbd_obj_request_get(obj_request);
2074 parent_request->obj_request = obj_request;
2076 return parent_request;
2079 static void rbd_parent_request_destroy(struct kref *kref)
2081 struct rbd_img_request *parent_request;
2082 struct rbd_obj_request *orig_request;
2084 parent_request = container_of(kref, struct rbd_img_request, kref);
2085 orig_request = parent_request->obj_request;
2087 parent_request->obj_request = NULL;
2088 rbd_obj_request_put(orig_request);
2089 img_request_child_clear(parent_request);
2091 rbd_img_request_destroy(kref);
2094 static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request)
2096 struct rbd_img_request *img_request;
2097 unsigned int xferred;
2101 rbd_assert(obj_request_img_data_test(obj_request));
2102 img_request = obj_request->img_request;
2104 rbd_assert(obj_request->xferred <= (u64)UINT_MAX);
2105 xferred = (unsigned int)obj_request->xferred;
2106 result = obj_request->result;
2108 struct rbd_device *rbd_dev = img_request->rbd_dev;
2110 rbd_warn(rbd_dev, "%s %llx at %llx (%llx)\n",
2111 img_request_write_test(img_request) ? "write" : "read",
2112 obj_request->length, obj_request->img_offset,
2113 obj_request->offset);
2114 rbd_warn(rbd_dev, " result %d xferred %x\n",
2116 if (!img_request->result)
2117 img_request->result = result;
2120 /* Image object requests don't own their page array */
2122 if (obj_request->type == OBJ_REQUEST_PAGES) {
2123 obj_request->pages = NULL;
2124 obj_request->page_count = 0;
2127 if (img_request_child_test(img_request)) {
2128 rbd_assert(img_request->obj_request != NULL);
2129 more = obj_request->which < img_request->obj_request_count - 1;
2131 rbd_assert(img_request->rq != NULL);
2132 more = blk_end_request(img_request->rq, result, xferred);
2138 static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
2140 struct rbd_img_request *img_request;
2141 u32 which = obj_request->which;
2144 rbd_assert(obj_request_img_data_test(obj_request));
2145 img_request = obj_request->img_request;
2147 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
2148 rbd_assert(img_request != NULL);
2149 rbd_assert(img_request->obj_request_count > 0);
2150 rbd_assert(which != BAD_WHICH);
2151 rbd_assert(which < img_request->obj_request_count);
2153 spin_lock_irq(&img_request->completion_lock);
2154 if (which != img_request->next_completion)
2157 for_each_obj_request_from(img_request, obj_request) {
2159 rbd_assert(which < img_request->obj_request_count);
2161 if (!obj_request_done_test(obj_request))
2163 more = rbd_img_obj_end_request(obj_request);
2167 rbd_assert(more ^ (which == img_request->obj_request_count));
2168 img_request->next_completion = which;
2170 spin_unlock_irq(&img_request->completion_lock);
2171 rbd_img_request_put(img_request);
2174 rbd_img_request_complete(img_request);
2178 * Split up an image request into one or more object requests, each
2179 * to a different object. The "type" parameter indicates whether
2180 * "data_desc" is the pointer to the head of a list of bio
2181 * structures, or the base of a page array. In either case this
2182 * function assumes data_desc describes memory sufficient to hold
2183 * all data described by the image request.
2185 static int rbd_img_request_fill(struct rbd_img_request *img_request,
2186 enum obj_request_type type,
2189 struct rbd_device *rbd_dev = img_request->rbd_dev;
2190 struct rbd_obj_request *obj_request = NULL;
2191 struct rbd_obj_request *next_obj_request;
2192 bool write_request = img_request_write_test(img_request);
2193 struct bio *bio_list = 0;
2194 unsigned int bio_offset = 0;
2195 struct page **pages = 0;
2200 dout("%s: img %p type %d data_desc %p\n", __func__, img_request,
2201 (int)type, data_desc);
2203 opcode = write_request ? CEPH_OSD_OP_WRITE : CEPH_OSD_OP_READ;
2204 img_offset = img_request->offset;
2205 resid = img_request->length;
2206 rbd_assert(resid > 0);
2208 if (type == OBJ_REQUEST_BIO) {
2209 bio_list = data_desc;
2210 rbd_assert(img_offset == bio_list->bi_sector << SECTOR_SHIFT);
2212 rbd_assert(type == OBJ_REQUEST_PAGES);
2217 struct ceph_osd_request *osd_req;
2218 const char *object_name;
2222 object_name = rbd_segment_name(rbd_dev, img_offset);
2225 offset = rbd_segment_offset(rbd_dev, img_offset);
2226 length = rbd_segment_length(rbd_dev, img_offset, resid);
2227 obj_request = rbd_obj_request_create(object_name,
2228 offset, length, type);
2229 /* object request has its own copy of the object name */
2230 rbd_segment_name_free(object_name);
2234 * set obj_request->img_request before creating the
2235 * osd_request so that it gets the right snapc
2237 rbd_img_obj_request_add(img_request, obj_request);
2239 if (type == OBJ_REQUEST_BIO) {
2240 unsigned int clone_size;
2242 rbd_assert(length <= (u64)UINT_MAX);
2243 clone_size = (unsigned int)length;
2244 obj_request->bio_list =
2245 bio_chain_clone_range(&bio_list,
2249 if (!obj_request->bio_list)
2252 unsigned int page_count;
2254 obj_request->pages = pages;
2255 page_count = (u32)calc_pages_for(offset, length);
2256 obj_request->page_count = page_count;
2257 if ((offset + length) & ~PAGE_MASK)
2258 page_count--; /* more on last page */
2259 pages += page_count;
2262 osd_req = rbd_osd_req_create(rbd_dev, write_request,
2266 obj_request->osd_req = osd_req;
2267 obj_request->callback = rbd_img_obj_callback;
2268 rbd_img_request_get(img_request);
2270 osd_req_op_extent_init(osd_req, 0, opcode, offset, length,
2272 if (type == OBJ_REQUEST_BIO)
2273 osd_req_op_extent_osd_data_bio(osd_req, 0,
2274 obj_request->bio_list, length);
2276 osd_req_op_extent_osd_data_pages(osd_req, 0,
2277 obj_request->pages, length,
2278 offset & ~PAGE_MASK, false, false);
2281 rbd_osd_req_format_write(obj_request);
2283 rbd_osd_req_format_read(obj_request);
2285 obj_request->img_offset = img_offset;
2287 img_offset += length;
2294 rbd_obj_request_put(obj_request);
2296 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2297 rbd_img_obj_request_del(img_request, obj_request);
2303 rbd_img_obj_copyup_callback(struct rbd_obj_request *obj_request)
2305 struct rbd_img_request *img_request;
2306 struct rbd_device *rbd_dev;
2307 struct page **pages;
2310 rbd_assert(obj_request->type == OBJ_REQUEST_BIO);
2311 rbd_assert(obj_request_img_data_test(obj_request));
2312 img_request = obj_request->img_request;
2313 rbd_assert(img_request);
2315 rbd_dev = img_request->rbd_dev;
2316 rbd_assert(rbd_dev);
2318 pages = obj_request->copyup_pages;
2319 rbd_assert(pages != NULL);
2320 obj_request->copyup_pages = NULL;
2321 page_count = obj_request->copyup_page_count;
2322 rbd_assert(page_count);
2323 obj_request->copyup_page_count = 0;
2324 ceph_release_page_vector(pages, page_count);
2327 * We want the transfer count to reflect the size of the
2328 * original write request. There is no such thing as a
2329 * successful short write, so if the request was successful
2330 * we can just set it to the originally-requested length.
2332 if (!obj_request->result)
2333 obj_request->xferred = obj_request->length;
2335 /* Finish up with the normal image object callback */
2337 rbd_img_obj_callback(obj_request);
2341 rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request)
2343 struct rbd_obj_request *orig_request;
2344 struct ceph_osd_request *osd_req;
2345 struct ceph_osd_client *osdc;
2346 struct rbd_device *rbd_dev;
2347 struct page **pages;
2354 rbd_assert(img_request_child_test(img_request));
2356 /* First get what we need from the image request */
2358 pages = img_request->copyup_pages;
2359 rbd_assert(pages != NULL);
2360 img_request->copyup_pages = NULL;
2361 page_count = img_request->copyup_page_count;
2362 rbd_assert(page_count);
2363 img_request->copyup_page_count = 0;
2365 orig_request = img_request->obj_request;
2366 rbd_assert(orig_request != NULL);
2367 rbd_assert(obj_request_type_valid(orig_request->type));
2368 img_result = img_request->result;
2369 parent_length = img_request->length;
2370 rbd_assert(parent_length == img_request->xferred);
2371 rbd_img_request_put(img_request);
2373 rbd_assert(orig_request->img_request);
2374 rbd_dev = orig_request->img_request->rbd_dev;
2375 rbd_assert(rbd_dev);
2378 * If the overlap has become 0 (most likely because the
2379 * image has been flattened) we need to free the pages
2380 * and re-submit the original write request.
2382 if (!rbd_dev->parent_overlap) {
2383 struct ceph_osd_client *osdc;
2385 ceph_release_page_vector(pages, page_count);
2386 osdc = &rbd_dev->rbd_client->client->osdc;
2387 img_result = rbd_obj_request_submit(osdc, orig_request);
2396 * The original osd request is of no use to use any more.
2397 * We need a new one that can hold the two ops in a copyup
2398 * request. Allocate the new copyup osd request for the
2399 * original request, and release the old one.
2401 img_result = -ENOMEM;
2402 osd_req = rbd_osd_req_create_copyup(orig_request);
2405 rbd_osd_req_destroy(orig_request->osd_req);
2406 orig_request->osd_req = osd_req;
2407 orig_request->copyup_pages = pages;
2408 orig_request->copyup_page_count = page_count;
2410 /* Initialize the copyup op */
2412 osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup");
2413 osd_req_op_cls_request_data_pages(osd_req, 0, pages, parent_length, 0,
2416 /* Then the original write request op */
2418 offset = orig_request->offset;
2419 length = orig_request->length;
2420 osd_req_op_extent_init(osd_req, 1, CEPH_OSD_OP_WRITE,
2421 offset, length, 0, 0);
2422 if (orig_request->type == OBJ_REQUEST_BIO)
2423 osd_req_op_extent_osd_data_bio(osd_req, 1,
2424 orig_request->bio_list, length);
2426 osd_req_op_extent_osd_data_pages(osd_req, 1,
2427 orig_request->pages, length,
2428 offset & ~PAGE_MASK, false, false);
2430 rbd_osd_req_format_write(orig_request);
2432 /* All set, send it off. */
2434 orig_request->callback = rbd_img_obj_copyup_callback;
2435 osdc = &rbd_dev->rbd_client->client->osdc;
2436 img_result = rbd_obj_request_submit(osdc, orig_request);
2440 /* Record the error code and complete the request */
2442 orig_request->result = img_result;
2443 orig_request->xferred = 0;
2444 obj_request_done_set(orig_request);
2445 rbd_obj_request_complete(orig_request);
2449 * Read from the parent image the range of data that covers the
2450 * entire target of the given object request. This is used for
2451 * satisfying a layered image write request when the target of an
2452 * object request from the image request does not exist.
2454 * A page array big enough to hold the returned data is allocated
2455 * and supplied to rbd_img_request_fill() as the "data descriptor."
2456 * When the read completes, this page array will be transferred to
2457 * the original object request for the copyup operation.
2459 * If an error occurs, record it as the result of the original
2460 * object request and mark it done so it gets completed.
2462 static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request)
2464 struct rbd_img_request *img_request = NULL;
2465 struct rbd_img_request *parent_request = NULL;
2466 struct rbd_device *rbd_dev;
2469 struct page **pages = NULL;
2473 rbd_assert(obj_request_img_data_test(obj_request));
2474 rbd_assert(obj_request_type_valid(obj_request->type));
2476 img_request = obj_request->img_request;
2477 rbd_assert(img_request != NULL);
2478 rbd_dev = img_request->rbd_dev;
2479 rbd_assert(rbd_dev->parent != NULL);
2482 * Determine the byte range covered by the object in the
2483 * child image to which the original request was to be sent.
2485 img_offset = obj_request->img_offset - obj_request->offset;
2486 length = (u64)1 << rbd_dev->header.obj_order;
2489 * There is no defined parent data beyond the parent
2490 * overlap, so limit what we read at that boundary if
2493 if (img_offset + length > rbd_dev->parent_overlap) {
2494 rbd_assert(img_offset < rbd_dev->parent_overlap);
2495 length = rbd_dev->parent_overlap - img_offset;
2499 * Allocate a page array big enough to receive the data read
2502 page_count = (u32)calc_pages_for(0, length);
2503 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2504 if (IS_ERR(pages)) {
2505 result = PTR_ERR(pages);
2511 parent_request = rbd_parent_request_create(obj_request,
2512 img_offset, length);
2513 if (!parent_request)
2516 result = rbd_img_request_fill(parent_request, OBJ_REQUEST_PAGES, pages);
2519 parent_request->copyup_pages = pages;
2520 parent_request->copyup_page_count = page_count;
2522 parent_request->callback = rbd_img_obj_parent_read_full_callback;
2523 result = rbd_img_request_submit(parent_request);
2527 parent_request->copyup_pages = NULL;
2528 parent_request->copyup_page_count = 0;
2529 parent_request->obj_request = NULL;
2530 rbd_obj_request_put(obj_request);
2533 ceph_release_page_vector(pages, page_count);
2535 rbd_img_request_put(parent_request);
2536 obj_request->result = result;
2537 obj_request->xferred = 0;
2538 obj_request_done_set(obj_request);
2543 static void rbd_img_obj_exists_callback(struct rbd_obj_request *obj_request)
2545 struct rbd_obj_request *orig_request;
2546 struct rbd_device *rbd_dev;
2549 rbd_assert(!obj_request_img_data_test(obj_request));
2552 * All we need from the object request is the original
2553 * request and the result of the STAT op. Grab those, then
2554 * we're done with the request.
2556 orig_request = obj_request->obj_request;
2557 obj_request->obj_request = NULL;
2558 rbd_assert(orig_request);
2559 rbd_assert(orig_request->img_request);
2561 result = obj_request->result;
2562 obj_request->result = 0;
2564 dout("%s: obj %p for obj %p result %d %llu/%llu\n", __func__,
2565 obj_request, orig_request, result,
2566 obj_request->xferred, obj_request->length);
2567 rbd_obj_request_put(obj_request);
2570 * If the overlap has become 0 (most likely because the
2571 * image has been flattened) we need to free the pages
2572 * and re-submit the original write request.
2574 rbd_dev = orig_request->img_request->rbd_dev;
2575 if (!rbd_dev->parent_overlap) {
2576 struct ceph_osd_client *osdc;
2578 rbd_obj_request_put(orig_request);
2579 osdc = &rbd_dev->rbd_client->client->osdc;
2580 result = rbd_obj_request_submit(osdc, orig_request);
2586 * Our only purpose here is to determine whether the object
2587 * exists, and we don't want to treat the non-existence as
2588 * an error. If something else comes back, transfer the
2589 * error to the original request and complete it now.
2592 obj_request_existence_set(orig_request, true);
2593 } else if (result == -ENOENT) {
2594 obj_request_existence_set(orig_request, false);
2595 } else if (result) {
2596 orig_request->result = result;
2601 * Resubmit the original request now that we have recorded
2602 * whether the target object exists.
2604 orig_request->result = rbd_img_obj_request_submit(orig_request);
2606 if (orig_request->result)
2607 rbd_obj_request_complete(orig_request);
2608 rbd_obj_request_put(orig_request);
2611 static int rbd_img_obj_exists_submit(struct rbd_obj_request *obj_request)
2613 struct rbd_obj_request *stat_request;
2614 struct rbd_device *rbd_dev;
2615 struct ceph_osd_client *osdc;
2616 struct page **pages = NULL;
2622 * The response data for a STAT call consists of:
2629 size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32);
2630 page_count = (u32)calc_pages_for(0, size);
2631 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2633 return PTR_ERR(pages);
2636 stat_request = rbd_obj_request_create(obj_request->object_name, 0, 0,
2641 rbd_obj_request_get(obj_request);
2642 stat_request->obj_request = obj_request;
2643 stat_request->pages = pages;
2644 stat_request->page_count = page_count;
2646 rbd_assert(obj_request->img_request);
2647 rbd_dev = obj_request->img_request->rbd_dev;
2648 stat_request->osd_req = rbd_osd_req_create(rbd_dev, false,
2650 if (!stat_request->osd_req)
2652 stat_request->callback = rbd_img_obj_exists_callback;
2654 osd_req_op_init(stat_request->osd_req, 0, CEPH_OSD_OP_STAT);
2655 osd_req_op_raw_data_in_pages(stat_request->osd_req, 0, pages, size, 0,
2657 rbd_osd_req_format_read(stat_request);
2659 osdc = &rbd_dev->rbd_client->client->osdc;
2660 ret = rbd_obj_request_submit(osdc, stat_request);
2663 rbd_obj_request_put(obj_request);
2668 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request)
2670 struct rbd_img_request *img_request;
2671 struct rbd_device *rbd_dev;
2674 rbd_assert(obj_request_img_data_test(obj_request));
2676 img_request = obj_request->img_request;
2677 rbd_assert(img_request);
2678 rbd_dev = img_request->rbd_dev;
2681 * Only writes to layered images need special handling.
2682 * Reads and non-layered writes are simple object requests.
2683 * Layered writes that start beyond the end of the overlap
2684 * with the parent have no parent data, so they too are
2685 * simple object requests. Finally, if the target object is
2686 * known to already exist, its parent data has already been
2687 * copied, so a write to the object can also be handled as a
2688 * simple object request.
2690 if (!img_request_write_test(img_request) ||
2691 !img_request_layered_test(img_request) ||
2692 !obj_request_overlaps_parent(obj_request) ||
2693 ((known = obj_request_known_test(obj_request)) &&
2694 obj_request_exists_test(obj_request))) {
2696 struct rbd_device *rbd_dev;
2697 struct ceph_osd_client *osdc;
2699 rbd_dev = obj_request->img_request->rbd_dev;
2700 osdc = &rbd_dev->rbd_client->client->osdc;
2702 return rbd_obj_request_submit(osdc, obj_request);
2706 * It's a layered write. The target object might exist but
2707 * we may not know that yet. If we know it doesn't exist,
2708 * start by reading the data for the full target object from
2709 * the parent so we can use it for a copyup to the target.
2712 return rbd_img_obj_parent_read_full(obj_request);
2714 /* We don't know whether the target exists. Go find out. */
2716 return rbd_img_obj_exists_submit(obj_request);
2719 static int rbd_img_request_submit(struct rbd_img_request *img_request)
2721 struct rbd_obj_request *obj_request;
2722 struct rbd_obj_request *next_obj_request;
2724 dout("%s: img %p\n", __func__, img_request);
2725 for_each_obj_request_safe(img_request, obj_request, next_obj_request) {
2728 ret = rbd_img_obj_request_submit(obj_request);
2736 static void rbd_img_parent_read_callback(struct rbd_img_request *img_request)
2738 struct rbd_obj_request *obj_request;
2739 struct rbd_device *rbd_dev;
2744 rbd_assert(img_request_child_test(img_request));
2746 /* First get what we need from the image request and release it */
2748 obj_request = img_request->obj_request;
2749 img_xferred = img_request->xferred;
2750 img_result = img_request->result;
2751 rbd_img_request_put(img_request);
2754 * If the overlap has become 0 (most likely because the
2755 * image has been flattened) we need to re-submit the
2758 rbd_assert(obj_request);
2759 rbd_assert(obj_request->img_request);
2760 rbd_dev = obj_request->img_request->rbd_dev;
2761 if (!rbd_dev->parent_overlap) {
2762 struct ceph_osd_client *osdc;
2764 osdc = &rbd_dev->rbd_client->client->osdc;
2765 img_result = rbd_obj_request_submit(osdc, obj_request);
2770 obj_request->result = img_result;
2771 if (obj_request->result)
2775 * We need to zero anything beyond the parent overlap
2776 * boundary. Since rbd_img_obj_request_read_callback()
2777 * will zero anything beyond the end of a short read, an
2778 * easy way to do this is to pretend the data from the
2779 * parent came up short--ending at the overlap boundary.
2781 rbd_assert(obj_request->img_offset < U64_MAX - obj_request->length);
2782 obj_end = obj_request->img_offset + obj_request->length;
2783 if (obj_end > rbd_dev->parent_overlap) {
2786 if (obj_request->img_offset < rbd_dev->parent_overlap)
2787 xferred = rbd_dev->parent_overlap -
2788 obj_request->img_offset;
2790 obj_request->xferred = min(img_xferred, xferred);
2792 obj_request->xferred = img_xferred;
2795 rbd_img_obj_request_read_callback(obj_request);
2796 rbd_obj_request_complete(obj_request);
2799 static void rbd_img_parent_read(struct rbd_obj_request *obj_request)
2801 struct rbd_img_request *img_request;
2804 rbd_assert(obj_request_img_data_test(obj_request));
2805 rbd_assert(obj_request->img_request != NULL);
2806 rbd_assert(obj_request->result == (s32) -ENOENT);
2807 rbd_assert(obj_request_type_valid(obj_request->type));
2809 /* rbd_read_finish(obj_request, obj_request->length); */
2810 img_request = rbd_parent_request_create(obj_request,
2811 obj_request->img_offset,
2812 obj_request->length);
2817 if (obj_request->type == OBJ_REQUEST_BIO)
2818 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
2819 obj_request->bio_list);
2821 result = rbd_img_request_fill(img_request, OBJ_REQUEST_PAGES,
2822 obj_request->pages);
2826 img_request->callback = rbd_img_parent_read_callback;
2827 result = rbd_img_request_submit(img_request);
2834 rbd_img_request_put(img_request);
2835 obj_request->result = result;
2836 obj_request->xferred = 0;
2837 obj_request_done_set(obj_request);
2840 static int rbd_obj_notify_ack_sync(struct rbd_device *rbd_dev, u64 notify_id)
2842 struct rbd_obj_request *obj_request;
2843 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2846 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
2847 OBJ_REQUEST_NODATA);
2852 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
2853 if (!obj_request->osd_req)
2856 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK,
2858 rbd_osd_req_format_read(obj_request);
2860 ret = rbd_obj_request_submit(osdc, obj_request);
2863 ret = rbd_obj_request_wait(obj_request);
2865 rbd_obj_request_put(obj_request);
2870 static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
2872 struct rbd_device *rbd_dev = (struct rbd_device *)data;
2878 dout("%s: \"%s\" notify_id %llu opcode %u\n", __func__,
2879 rbd_dev->header_name, (unsigned long long)notify_id,
2880 (unsigned int)opcode);
2881 ret = rbd_dev_refresh(rbd_dev);
2883 rbd_warn(rbd_dev, ": header refresh error (%d)\n", ret);
2885 rbd_obj_notify_ack_sync(rbd_dev, notify_id);
2889 * Request sync osd watch/unwatch. The value of "start" determines
2890 * whether a watch request is being initiated or torn down.
2892 static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, bool start)
2894 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2895 struct rbd_obj_request *obj_request;
2898 rbd_assert(start ^ !!rbd_dev->watch_event);
2899 rbd_assert(start ^ !!rbd_dev->watch_request);
2902 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
2903 &rbd_dev->watch_event);
2906 rbd_assert(rbd_dev->watch_event != NULL);
2910 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
2911 OBJ_REQUEST_NODATA);
2915 obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, obj_request);
2916 if (!obj_request->osd_req)
2920 ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
2922 ceph_osdc_unregister_linger_request(osdc,
2923 rbd_dev->watch_request->osd_req);
2925 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
2926 rbd_dev->watch_event->cookie, 0, start ? 1 : 0);
2927 rbd_osd_req_format_write(obj_request);
2929 ret = rbd_obj_request_submit(osdc, obj_request);
2932 ret = rbd_obj_request_wait(obj_request);
2935 ret = obj_request->result;
2940 * A watch request is set to linger, so the underlying osd
2941 * request won't go away until we unregister it. We retain
2942 * a pointer to the object request during that time (in
2943 * rbd_dev->watch_request), so we'll keep a reference to
2944 * it. We'll drop that reference (below) after we've
2948 rbd_dev->watch_request = obj_request;
2953 /* We have successfully torn down the watch request */
2955 rbd_obj_request_put(rbd_dev->watch_request);
2956 rbd_dev->watch_request = NULL;
2958 /* Cancel the event if we're tearing down, or on error */
2959 ceph_osdc_cancel_event(rbd_dev->watch_event);
2960 rbd_dev->watch_event = NULL;
2962 rbd_obj_request_put(obj_request);
2968 * Synchronous osd object method call. Returns the number of bytes
2969 * returned in the outbound buffer, or a negative error code.
2971 static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
2972 const char *object_name,
2973 const char *class_name,
2974 const char *method_name,
2975 const void *outbound,
2976 size_t outbound_size,
2978 size_t inbound_size)
2980 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2981 struct rbd_obj_request *obj_request;
2982 struct page **pages;
2987 * Method calls are ultimately read operations. The result
2988 * should placed into the inbound buffer provided. They
2989 * also supply outbound data--parameters for the object
2990 * method. Currently if this is present it will be a
2993 page_count = (u32)calc_pages_for(0, inbound_size);
2994 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2996 return PTR_ERR(pages);
2999 obj_request = rbd_obj_request_create(object_name, 0, inbound_size,
3004 obj_request->pages = pages;
3005 obj_request->page_count = page_count;
3007 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
3008 if (!obj_request->osd_req)
3011 osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL,
3012 class_name, method_name);
3013 if (outbound_size) {
3014 struct ceph_pagelist *pagelist;
3016 pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS);
3020 ceph_pagelist_init(pagelist);
3021 ceph_pagelist_append(pagelist, outbound, outbound_size);
3022 osd_req_op_cls_request_data_pagelist(obj_request->osd_req, 0,
3025 osd_req_op_cls_response_data_pages(obj_request->osd_req, 0,
3026 obj_request->pages, inbound_size,
3028 rbd_osd_req_format_read(obj_request);
3030 ret = rbd_obj_request_submit(osdc, obj_request);
3033 ret = rbd_obj_request_wait(obj_request);
3037 ret = obj_request->result;
3041 rbd_assert(obj_request->xferred < (u64)INT_MAX);
3042 ret = (int)obj_request->xferred;
3043 ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred);
3046 rbd_obj_request_put(obj_request);
3048 ceph_release_page_vector(pages, page_count);
3053 static void rbd_request_fn(struct request_queue *q)
3054 __releases(q->queue_lock) __acquires(q->queue_lock)
3056 struct rbd_device *rbd_dev = q->queuedata;
3057 bool read_only = rbd_dev->mapping.read_only;
3061 while ((rq = blk_fetch_request(q))) {
3062 bool write_request = rq_data_dir(rq) == WRITE;
3063 struct rbd_img_request *img_request;
3067 /* Ignore any non-FS requests that filter through. */
3069 if (rq->cmd_type != REQ_TYPE_FS) {
3070 dout("%s: non-fs request type %d\n", __func__,
3071 (int) rq->cmd_type);
3072 __blk_end_request_all(rq, 0);
3076 /* Ignore/skip any zero-length requests */
3078 offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT;
3079 length = (u64) blk_rq_bytes(rq);
3082 dout("%s: zero-length request\n", __func__);
3083 __blk_end_request_all(rq, 0);
3087 spin_unlock_irq(q->queue_lock);
3089 /* Disallow writes to a read-only device */
3091 if (write_request) {
3095 rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP);
3099 * Quit early if the mapped snapshot no longer
3100 * exists. It's still possible the snapshot will
3101 * have disappeared by the time our request arrives
3102 * at the osd, but there's no sense in sending it if
3105 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) {
3106 dout("request for non-existent snapshot");
3107 rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP);
3113 if (offset && length > U64_MAX - offset + 1) {
3114 rbd_warn(rbd_dev, "bad request range (%llu~%llu)\n",
3116 goto end_request; /* Shouldn't happen */
3120 if (offset + length > rbd_dev->mapping.size) {
3121 rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)\n",
3122 offset, length, rbd_dev->mapping.size);
3127 img_request = rbd_img_request_create(rbd_dev, offset, length,
3132 img_request->rq = rq;
3134 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
3137 result = rbd_img_request_submit(img_request);
3139 rbd_img_request_put(img_request);
3141 spin_lock_irq(q->queue_lock);
3143 rbd_warn(rbd_dev, "%s %llx at %llx result %d\n",
3144 write_request ? "write" : "read",
3145 length, offset, result);
3147 __blk_end_request_all(rq, result);
3153 * a queue callback. Makes sure that we don't create a bio that spans across
3154 * multiple osd objects. One exception would be with a single page bios,
3155 * which we handle later at bio_chain_clone_range()
3157 static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
3158 struct bio_vec *bvec)
3160 struct rbd_device *rbd_dev = q->queuedata;
3161 sector_t sector_offset;
3162 sector_t sectors_per_obj;
3163 sector_t obj_sector_offset;
3167 * Find how far into its rbd object the partition-relative
3168 * bio start sector is to offset relative to the enclosing
3171 sector_offset = get_start_sect(bmd->bi_bdev) + bmd->bi_sector;
3172 sectors_per_obj = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT);
3173 obj_sector_offset = sector_offset & (sectors_per_obj - 1);
3176 * Compute the number of bytes from that offset to the end
3177 * of the object. Account for what's already used by the bio.
3179 ret = (int) (sectors_per_obj - obj_sector_offset) << SECTOR_SHIFT;
3180 if (ret > bmd->bi_size)
3181 ret -= bmd->bi_size;
3186 * Don't send back more than was asked for. And if the bio
3187 * was empty, let the whole thing through because: "Note
3188 * that a block device *must* allow a single page to be
3189 * added to an empty bio."
3191 rbd_assert(bvec->bv_len <= PAGE_SIZE);
3192 if (ret > (int) bvec->bv_len || !bmd->bi_size)
3193 ret = (int) bvec->bv_len;
3198 static void rbd_free_disk(struct rbd_device *rbd_dev)
3200 struct gendisk *disk = rbd_dev->disk;
3205 rbd_dev->disk = NULL;
3206 if (disk->flags & GENHD_FL_UP) {
3209 blk_cleanup_queue(disk->queue);
3214 static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
3215 const char *object_name,
3216 u64 offset, u64 length, void *buf)
3219 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3220 struct rbd_obj_request *obj_request;
3221 struct page **pages = NULL;
3226 page_count = (u32) calc_pages_for(offset, length);
3227 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
3229 return PTR_ERR(pages);
3232 obj_request = rbd_obj_request_create(object_name, offset, length,
3237 obj_request->pages = pages;
3238 obj_request->page_count = page_count;
3240 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
3241 if (!obj_request->osd_req)
3244 osd_req_op_extent_init(obj_request->osd_req, 0, CEPH_OSD_OP_READ,
3245 offset, length, 0, 0);
3246 osd_req_op_extent_osd_data_pages(obj_request->osd_req, 0,
3248 obj_request->length,
3249 obj_request->offset & ~PAGE_MASK,
3251 rbd_osd_req_format_read(obj_request);
3253 ret = rbd_obj_request_submit(osdc, obj_request);
3256 ret = rbd_obj_request_wait(obj_request);
3260 ret = obj_request->result;
3264 rbd_assert(obj_request->xferred <= (u64) SIZE_MAX);
3265 size = (size_t) obj_request->xferred;
3266 ceph_copy_from_page_vector(pages, buf, 0, size);
3267 rbd_assert(size <= (size_t)INT_MAX);
3271 rbd_obj_request_put(obj_request);
3273 ceph_release_page_vector(pages, page_count);
3279 * Read the complete header for the given rbd device. On successful
3280 * return, the rbd_dev->header field will contain up-to-date
3281 * information about the image.
3283 static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
3285 struct rbd_image_header_ondisk *ondisk = NULL;
3292 * The complete header will include an array of its 64-bit
3293 * snapshot ids, followed by the names of those snapshots as
3294 * a contiguous block of NUL-terminated strings. Note that
3295 * the number of snapshots could change by the time we read
3296 * it in, in which case we re-read it.
3303 size = sizeof (*ondisk);
3304 size += snap_count * sizeof (struct rbd_image_snap_ondisk);
3306 ondisk = kmalloc(size, GFP_KERNEL);
3310 ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name,
3314 if ((size_t)ret < size) {
3316 rbd_warn(rbd_dev, "short header read (want %zd got %d)",
3320 if (!rbd_dev_ondisk_valid(ondisk)) {
3322 rbd_warn(rbd_dev, "invalid header");
3326 names_size = le64_to_cpu(ondisk->snap_names_len);
3327 want_count = snap_count;
3328 snap_count = le32_to_cpu(ondisk->snap_count);
3329 } while (snap_count != want_count);
3331 ret = rbd_header_from_disk(rbd_dev, ondisk);
3339 * Clear the rbd device's EXISTS flag if the snapshot it's mapped to
3340 * has disappeared from the (just updated) snapshot context.
3342 static void rbd_exists_validate(struct rbd_device *rbd_dev)
3346 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags))
3349 snap_id = rbd_dev->spec->snap_id;
3350 if (snap_id == CEPH_NOSNAP)
3353 if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX)
3354 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
3357 static void rbd_dev_update_size(struct rbd_device *rbd_dev)
3363 * Don't hold the lock while doing disk operations,
3364 * or lock ordering will conflict with the bdev mutex via:
3365 * rbd_add() -> blkdev_get() -> rbd_open()
3367 spin_lock_irq(&rbd_dev->lock);
3368 removing = test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags);
3369 spin_unlock_irq(&rbd_dev->lock);
3371 * If the device is being removed, rbd_dev->disk has
3372 * been destroyed, so don't try to update its size
3375 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
3376 dout("setting size to %llu sectors", (unsigned long long)size);
3377 set_capacity(rbd_dev->disk, size);
3378 revalidate_disk(rbd_dev->disk);
3382 static int rbd_dev_refresh(struct rbd_device *rbd_dev)
3387 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
3388 mapping_size = rbd_dev->mapping.size;
3389 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
3390 if (rbd_dev->image_format == 1)
3391 ret = rbd_dev_v1_header_info(rbd_dev);
3393 ret = rbd_dev_v2_header_info(rbd_dev);
3395 /* If it's a mapped snapshot, validate its EXISTS flag */
3397 rbd_exists_validate(rbd_dev);
3398 mutex_unlock(&ctl_mutex);
3399 if (mapping_size != rbd_dev->mapping.size) {
3400 rbd_dev_update_size(rbd_dev);
3406 static int rbd_init_disk(struct rbd_device *rbd_dev)
3408 struct gendisk *disk;
3409 struct request_queue *q;
3412 /* create gendisk info */
3413 disk = alloc_disk(RBD_MINORS_PER_MAJOR);
3417 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
3419 disk->major = rbd_dev->major;
3420 disk->first_minor = 0;
3421 disk->fops = &rbd_bd_ops;
3422 disk->private_data = rbd_dev;
3424 q = blk_init_queue(rbd_request_fn, &rbd_dev->lock);
3428 /* We use the default size, but let's be explicit about it. */
3429 blk_queue_physical_block_size(q, SECTOR_SIZE);
3431 /* set io sizes to object size */
3432 segment_size = rbd_obj_bytes(&rbd_dev->header);
3433 blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
3434 blk_queue_max_segment_size(q, segment_size);
3435 blk_queue_io_min(q, segment_size);
3436 blk_queue_io_opt(q, segment_size);
3438 blk_queue_merge_bvec(q, rbd_merge_bvec);
3441 q->queuedata = rbd_dev;
3443 rbd_dev->disk = disk;
3456 static struct rbd_device *dev_to_rbd_dev(struct device *dev)
3458 return container_of(dev, struct rbd_device, dev);
3461 static ssize_t rbd_size_show(struct device *dev,
3462 struct device_attribute *attr, char *buf)
3464 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3466 return sprintf(buf, "%llu\n",
3467 (unsigned long long)rbd_dev->mapping.size);
3471 * Note this shows the features for whatever's mapped, which is not
3472 * necessarily the base image.
3474 static ssize_t rbd_features_show(struct device *dev,
3475 struct device_attribute *attr, char *buf)
3477 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3479 return sprintf(buf, "0x%016llx\n",
3480 (unsigned long long)rbd_dev->mapping.features);
3483 static ssize_t rbd_major_show(struct device *dev,
3484 struct device_attribute *attr, char *buf)
3486 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3489 return sprintf(buf, "%d\n", rbd_dev->major);
3491 return sprintf(buf, "(none)\n");
3495 static ssize_t rbd_client_id_show(struct device *dev,
3496 struct device_attribute *attr, char *buf)
3498 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3500 return sprintf(buf, "client%lld\n",
3501 ceph_client_id(rbd_dev->rbd_client->client));
3504 static ssize_t rbd_pool_show(struct device *dev,
3505 struct device_attribute *attr, char *buf)
3507 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3509 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
3512 static ssize_t rbd_pool_id_show(struct device *dev,
3513 struct device_attribute *attr, char *buf)
3515 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3517 return sprintf(buf, "%llu\n",
3518 (unsigned long long) rbd_dev->spec->pool_id);
3521 static ssize_t rbd_name_show(struct device *dev,
3522 struct device_attribute *attr, char *buf)
3524 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3526 if (rbd_dev->spec->image_name)
3527 return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
3529 return sprintf(buf, "(unknown)\n");
3532 static ssize_t rbd_image_id_show(struct device *dev,
3533 struct device_attribute *attr, char *buf)
3535 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3537 return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
3541 * Shows the name of the currently-mapped snapshot (or
3542 * RBD_SNAP_HEAD_NAME for the base image).
3544 static ssize_t rbd_snap_show(struct device *dev,
3545 struct device_attribute *attr,
3548 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3550 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
3554 * For an rbd v2 image, shows the pool id, image id, and snapshot id
3555 * for the parent image. If there is no parent, simply shows
3556 * "(no parent image)".
3558 static ssize_t rbd_parent_show(struct device *dev,
3559 struct device_attribute *attr,
3562 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3563 struct rbd_spec *spec = rbd_dev->parent_spec;
3568 return sprintf(buf, "(no parent image)\n");
3570 count = sprintf(bufp, "pool_id %llu\npool_name %s\n",
3571 (unsigned long long) spec->pool_id, spec->pool_name);
3576 count = sprintf(bufp, "image_id %s\nimage_name %s\n", spec->image_id,
3577 spec->image_name ? spec->image_name : "(unknown)");
3582 count = sprintf(bufp, "snap_id %llu\nsnap_name %s\n",
3583 (unsigned long long) spec->snap_id, spec->snap_name);
3588 count = sprintf(bufp, "overlap %llu\n", rbd_dev->parent_overlap);
3593 return (ssize_t) (bufp - buf);
3596 static ssize_t rbd_image_refresh(struct device *dev,
3597 struct device_attribute *attr,
3601 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3604 ret = rbd_dev_refresh(rbd_dev);
3606 rbd_warn(rbd_dev, ": manual header refresh error (%d)\n", ret);
3608 return ret < 0 ? ret : size;
3611 static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
3612 static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL);
3613 static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
3614 static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
3615 static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
3616 static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL);
3617 static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
3618 static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL);
3619 static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
3620 static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
3621 static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL);
3623 static struct attribute *rbd_attrs[] = {
3624 &dev_attr_size.attr,
3625 &dev_attr_features.attr,
3626 &dev_attr_major.attr,
3627 &dev_attr_client_id.attr,
3628 &dev_attr_pool.attr,
3629 &dev_attr_pool_id.attr,
3630 &dev_attr_name.attr,
3631 &dev_attr_image_id.attr,
3632 &dev_attr_current_snap.attr,
3633 &dev_attr_parent.attr,
3634 &dev_attr_refresh.attr,
3638 static struct attribute_group rbd_attr_group = {
3642 static const struct attribute_group *rbd_attr_groups[] = {
3647 static void rbd_sysfs_dev_release(struct device *dev)
3651 static struct device_type rbd_device_type = {
3653 .groups = rbd_attr_groups,
3654 .release = rbd_sysfs_dev_release,
3657 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
3659 kref_get(&spec->kref);
3664 static void rbd_spec_free(struct kref *kref);
3665 static void rbd_spec_put(struct rbd_spec *spec)
3668 kref_put(&spec->kref, rbd_spec_free);
3671 static struct rbd_spec *rbd_spec_alloc(void)
3673 struct rbd_spec *spec;
3675 spec = kzalloc(sizeof (*spec), GFP_KERNEL);
3678 kref_init(&spec->kref);
3683 static void rbd_spec_free(struct kref *kref)
3685 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
3687 kfree(spec->pool_name);
3688 kfree(spec->image_id);
3689 kfree(spec->image_name);
3690 kfree(spec->snap_name);
3694 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
3695 struct rbd_spec *spec)
3697 struct rbd_device *rbd_dev;
3699 rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL);
3703 spin_lock_init(&rbd_dev->lock);
3705 atomic_set(&rbd_dev->parent_ref, 0);
3706 INIT_LIST_HEAD(&rbd_dev->node);
3707 init_rwsem(&rbd_dev->header_rwsem);
3709 rbd_dev->spec = spec;
3710 rbd_dev->rbd_client = rbdc;
3712 /* Initialize the layout used for all rbd requests */
3714 rbd_dev->layout.fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3715 rbd_dev->layout.fl_stripe_count = cpu_to_le32(1);
3716 rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3717 rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id);
3722 static void rbd_dev_destroy(struct rbd_device *rbd_dev)
3724 rbd_put_client(rbd_dev->rbd_client);
3725 rbd_spec_put(rbd_dev->spec);
3730 * Get the size and object order for an image snapshot, or if
3731 * snap_id is CEPH_NOSNAP, gets this information for the base
3734 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
3735 u8 *order, u64 *snap_size)
3737 __le64 snapid = cpu_to_le64(snap_id);
3742 } __attribute__ ((packed)) size_buf = { 0 };
3744 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3746 &snapid, sizeof (snapid),
3747 &size_buf, sizeof (size_buf));
3748 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3751 if (ret < sizeof (size_buf))
3755 *order = size_buf.order;
3756 dout(" order %u", (unsigned int)*order);
3758 *snap_size = le64_to_cpu(size_buf.size);
3760 dout(" snap_id 0x%016llx snap_size = %llu\n",
3761 (unsigned long long)snap_id,
3762 (unsigned long long)*snap_size);
3767 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
3769 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
3770 &rbd_dev->header.obj_order,
3771 &rbd_dev->header.image_size);
3774 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
3780 reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL);
3784 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3785 "rbd", "get_object_prefix", NULL, 0,
3786 reply_buf, RBD_OBJ_PREFIX_LEN_MAX);
3787 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3792 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
3793 p + ret, NULL, GFP_NOIO);
3796 if (IS_ERR(rbd_dev->header.object_prefix)) {
3797 ret = PTR_ERR(rbd_dev->header.object_prefix);
3798 rbd_dev->header.object_prefix = NULL;
3800 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix);
3808 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
3811 __le64 snapid = cpu_to_le64(snap_id);
3815 } __attribute__ ((packed)) features_buf = { 0 };
3819 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3820 "rbd", "get_features",
3821 &snapid, sizeof (snapid),
3822 &features_buf, sizeof (features_buf));
3823 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3826 if (ret < sizeof (features_buf))
3829 incompat = le64_to_cpu(features_buf.incompat);
3830 if (incompat & ~RBD_FEATURES_SUPPORTED)
3833 *snap_features = le64_to_cpu(features_buf.features);
3835 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
3836 (unsigned long long)snap_id,
3837 (unsigned long long)*snap_features,
3838 (unsigned long long)le64_to_cpu(features_buf.incompat));
3843 static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
3845 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
3846 &rbd_dev->header.features);
3849 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
3851 struct rbd_spec *parent_spec;
3853 void *reply_buf = NULL;
3862 parent_spec = rbd_spec_alloc();
3866 size = sizeof (__le64) + /* pool_id */
3867 sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */
3868 sizeof (__le64) + /* snap_id */
3869 sizeof (__le64); /* overlap */
3870 reply_buf = kmalloc(size, GFP_KERNEL);
3876 snapid = cpu_to_le64(CEPH_NOSNAP);
3877 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3878 "rbd", "get_parent",
3879 &snapid, sizeof (snapid),
3881 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3886 end = reply_buf + ret;
3888 ceph_decode_64_safe(&p, end, pool_id, out_err);
3889 if (pool_id == CEPH_NOPOOL) {
3891 * Either the parent never existed, or we have
3892 * record of it but the image got flattened so it no
3893 * longer has a parent. When the parent of a
3894 * layered image disappears we immediately set the
3895 * overlap to 0. The effect of this is that all new
3896 * requests will be treated as if the image had no
3899 if (rbd_dev->parent_overlap) {
3900 rbd_dev->parent_overlap = 0;
3902 rbd_dev_parent_put(rbd_dev);
3903 pr_info("%s: clone image has been flattened\n",
3904 rbd_dev->disk->disk_name);
3907 goto out; /* No parent? No problem. */
3910 /* The ceph file layout needs to fit pool id in 32 bits */
3913 if (pool_id > (u64)U32_MAX) {
3914 rbd_warn(NULL, "parent pool id too large (%llu > %u)\n",
3915 (unsigned long long)pool_id, U32_MAX);
3918 parent_spec->pool_id = pool_id;
3920 image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
3921 if (IS_ERR(image_id)) {
3922 ret = PTR_ERR(image_id);
3925 parent_spec->image_id = image_id;
3926 ceph_decode_64_safe(&p, end, parent_spec->snap_id, out_err);
3927 ceph_decode_64_safe(&p, end, overlap, out_err);
3930 rbd_spec_put(rbd_dev->parent_spec);
3931 rbd_dev->parent_spec = parent_spec;
3932 parent_spec = NULL; /* rbd_dev now owns this */
3933 rbd_dev->parent_overlap = overlap;
3935 rbd_warn(rbd_dev, "ignoring parent of clone with overlap 0\n");
3941 rbd_spec_put(parent_spec);
3946 static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
3950 __le64 stripe_count;
3951 } __attribute__ ((packed)) striping_info_buf = { 0 };
3952 size_t size = sizeof (striping_info_buf);
3959 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3960 "rbd", "get_stripe_unit_count", NULL, 0,
3961 (char *)&striping_info_buf, size);
3962 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3969 * We don't actually support the "fancy striping" feature
3970 * (STRIPINGV2) yet, but if the striping sizes are the
3971 * defaults the behavior is the same as before. So find
3972 * out, and only fail if the image has non-default values.
3975 obj_size = (u64)1 << rbd_dev->header.obj_order;
3976 p = &striping_info_buf;
3977 stripe_unit = ceph_decode_64(&p);
3978 if (stripe_unit != obj_size) {
3979 rbd_warn(rbd_dev, "unsupported stripe unit "
3980 "(got %llu want %llu)",
3981 stripe_unit, obj_size);
3984 stripe_count = ceph_decode_64(&p);
3985 if (stripe_count != 1) {
3986 rbd_warn(rbd_dev, "unsupported stripe count "
3987 "(got %llu want 1)", stripe_count);
3990 rbd_dev->header.stripe_unit = stripe_unit;
3991 rbd_dev->header.stripe_count = stripe_count;
3996 static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
3998 size_t image_id_size;
4003 void *reply_buf = NULL;
4005 char *image_name = NULL;
4008 rbd_assert(!rbd_dev->spec->image_name);
4010 len = strlen(rbd_dev->spec->image_id);
4011 image_id_size = sizeof (__le32) + len;
4012 image_id = kmalloc(image_id_size, GFP_KERNEL);
4017 end = image_id + image_id_size;
4018 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
4020 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
4021 reply_buf = kmalloc(size, GFP_KERNEL);
4025 ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY,
4026 "rbd", "dir_get_name",
4027 image_id, image_id_size,
4032 end = reply_buf + ret;
4034 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
4035 if (IS_ERR(image_name))
4038 dout("%s: name is %s len is %zd\n", __func__, image_name, len);
4046 static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4048 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
4049 const char *snap_name;
4052 /* Skip over names until we find the one we are looking for */
4054 snap_name = rbd_dev->header.snap_names;
4055 while (which < snapc->num_snaps) {
4056 if (!strcmp(name, snap_name))
4057 return snapc->snaps[which];
4058 snap_name += strlen(snap_name) + 1;
4064 static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4066 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
4071 for (which = 0; !found && which < snapc->num_snaps; which++) {
4072 const char *snap_name;
4074 snap_id = snapc->snaps[which];
4075 snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
4076 if (IS_ERR(snap_name)) {
4077 /* ignore no-longer existing snapshots */
4078 if (PTR_ERR(snap_name) == -ENOENT)
4083 found = !strcmp(name, snap_name);
4086 return found ? snap_id : CEPH_NOSNAP;
4090 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
4091 * no snapshot by that name is found, or if an error occurs.
4093 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4095 if (rbd_dev->image_format == 1)
4096 return rbd_v1_snap_id_by_name(rbd_dev, name);
4098 return rbd_v2_snap_id_by_name(rbd_dev, name);
4102 * When an rbd image has a parent image, it is identified by the
4103 * pool, image, and snapshot ids (not names). This function fills
4104 * in the names for those ids. (It's OK if we can't figure out the
4105 * name for an image id, but the pool and snapshot ids should always
4106 * exist and have names.) All names in an rbd spec are dynamically
4109 * When an image being mapped (not a parent) is probed, we have the
4110 * pool name and pool id, image name and image id, and the snapshot
4111 * name. The only thing we're missing is the snapshot id.
4113 static int rbd_dev_spec_update(struct rbd_device *rbd_dev)
4115 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4116 struct rbd_spec *spec = rbd_dev->spec;
4117 const char *pool_name;
4118 const char *image_name;
4119 const char *snap_name;
4123 * An image being mapped will have the pool name (etc.), but
4124 * we need to look up the snapshot id.
4126 if (spec->pool_name) {
4127 if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
4130 snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
4131 if (snap_id == CEPH_NOSNAP)
4133 spec->snap_id = snap_id;
4135 spec->snap_id = CEPH_NOSNAP;
4141 /* Get the pool name; we have to make our own copy of this */
4143 pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
4145 rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
4148 pool_name = kstrdup(pool_name, GFP_KERNEL);
4152 /* Fetch the image name; tolerate failure here */
4154 image_name = rbd_dev_image_name(rbd_dev);
4156 rbd_warn(rbd_dev, "unable to get image name");
4158 /* Look up the snapshot name, and make a copy */
4160 snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
4161 if (IS_ERR(snap_name)) {
4162 ret = PTR_ERR(snap_name);
4166 spec->pool_name = pool_name;
4167 spec->image_name = image_name;
4168 spec->snap_name = snap_name;
4178 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
4187 struct ceph_snap_context *snapc;
4191 * We'll need room for the seq value (maximum snapshot id),
4192 * snapshot count, and array of that many snapshot ids.
4193 * For now we have a fixed upper limit on the number we're
4194 * prepared to receive.
4196 size = sizeof (__le64) + sizeof (__le32) +
4197 RBD_MAX_SNAP_COUNT * sizeof (__le64);
4198 reply_buf = kzalloc(size, GFP_KERNEL);
4202 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4203 "rbd", "get_snapcontext", NULL, 0,
4205 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4210 end = reply_buf + ret;
4212 ceph_decode_64_safe(&p, end, seq, out);
4213 ceph_decode_32_safe(&p, end, snap_count, out);
4216 * Make sure the reported number of snapshot ids wouldn't go
4217 * beyond the end of our buffer. But before checking that,
4218 * make sure the computed size of the snapshot context we
4219 * allocate is representable in a size_t.
4221 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
4226 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
4230 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
4236 for (i = 0; i < snap_count; i++)
4237 snapc->snaps[i] = ceph_decode_64(&p);
4239 ceph_put_snap_context(rbd_dev->header.snapc);
4240 rbd_dev->header.snapc = snapc;
4242 dout(" snap context seq = %llu, snap_count = %u\n",
4243 (unsigned long long)seq, (unsigned int)snap_count);
4250 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
4261 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
4262 reply_buf = kmalloc(size, GFP_KERNEL);
4264 return ERR_PTR(-ENOMEM);
4266 snapid = cpu_to_le64(snap_id);
4267 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4268 "rbd", "get_snapshot_name",
4269 &snapid, sizeof (snapid),
4271 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4273 snap_name = ERR_PTR(ret);
4278 end = reply_buf + ret;
4279 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
4280 if (IS_ERR(snap_name))
4283 dout(" snap_id 0x%016llx snap_name = %s\n",
4284 (unsigned long long)snap_id, snap_name);
4291 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
4293 bool first_time = rbd_dev->header.object_prefix == NULL;
4296 down_write(&rbd_dev->header_rwsem);
4298 ret = rbd_dev_v2_image_size(rbd_dev);
4303 ret = rbd_dev_v2_header_onetime(rbd_dev);
4309 * If the image supports layering, get the parent info. We
4310 * need to probe the first time regardless. Thereafter we
4311 * only need to if there's a parent, to see if it has
4312 * disappeared due to the mapped image getting flattened.
4314 if (rbd_dev->header.features & RBD_FEATURE_LAYERING &&
4315 (first_time || rbd_dev->parent_spec)) {
4318 ret = rbd_dev_v2_parent_info(rbd_dev);
4323 * Print a warning if this is the initial probe and
4324 * the image has a parent. Don't print it if the
4325 * image now being probed is itself a parent. We
4326 * can tell at this point because we won't know its
4327 * pool name yet (just its pool id).
4329 warn = rbd_dev->parent_spec && rbd_dev->spec->pool_name;
4330 if (first_time && warn)
4331 rbd_warn(rbd_dev, "WARNING: kernel layering "
4332 "is EXPERIMENTAL!");
4335 if (rbd_dev->spec->snap_id == CEPH_NOSNAP)
4336 if (rbd_dev->mapping.size != rbd_dev->header.image_size)
4337 rbd_dev->mapping.size = rbd_dev->header.image_size;
4339 ret = rbd_dev_v2_snap_context(rbd_dev);
4340 dout("rbd_dev_v2_snap_context returned %d\n", ret);
4342 up_write(&rbd_dev->header_rwsem);
4347 static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
4352 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
4354 dev = &rbd_dev->dev;
4355 dev->bus = &rbd_bus_type;
4356 dev->type = &rbd_device_type;
4357 dev->parent = &rbd_root_dev;
4358 dev->release = rbd_dev_device_release;
4359 dev_set_name(dev, "%d", rbd_dev->dev_id);
4360 ret = device_register(dev);
4362 mutex_unlock(&ctl_mutex);
4367 static void rbd_bus_del_dev(struct rbd_device *rbd_dev)
4369 device_unregister(&rbd_dev->dev);
4372 static atomic64_t rbd_dev_id_max = ATOMIC64_INIT(0);
4375 * Get a unique rbd identifier for the given new rbd_dev, and add
4376 * the rbd_dev to the global list. The minimum rbd id is 1.
4378 static void rbd_dev_id_get(struct rbd_device *rbd_dev)
4380 rbd_dev->dev_id = atomic64_inc_return(&rbd_dev_id_max);
4382 spin_lock(&rbd_dev_list_lock);
4383 list_add_tail(&rbd_dev->node, &rbd_dev_list);
4384 spin_unlock(&rbd_dev_list_lock);
4385 dout("rbd_dev %p given dev id %llu\n", rbd_dev,
4386 (unsigned long long) rbd_dev->dev_id);
4390 * Remove an rbd_dev from the global list, and record that its
4391 * identifier is no longer in use.
4393 static void rbd_dev_id_put(struct rbd_device *rbd_dev)
4395 struct list_head *tmp;
4396 int rbd_id = rbd_dev->dev_id;
4399 rbd_assert(rbd_id > 0);
4401 dout("rbd_dev %p released dev id %llu\n", rbd_dev,
4402 (unsigned long long) rbd_dev->dev_id);
4403 spin_lock(&rbd_dev_list_lock);
4404 list_del_init(&rbd_dev->node);
4407 * If the id being "put" is not the current maximum, there
4408 * is nothing special we need to do.
4410 if (rbd_id != atomic64_read(&rbd_dev_id_max)) {
4411 spin_unlock(&rbd_dev_list_lock);
4416 * We need to update the current maximum id. Search the
4417 * list to find out what it is. We're more likely to find
4418 * the maximum at the end, so search the list backward.
4421 list_for_each_prev(tmp, &rbd_dev_list) {
4422 struct rbd_device *rbd_dev;
4424 rbd_dev = list_entry(tmp, struct rbd_device, node);
4425 if (rbd_dev->dev_id > max_id)
4426 max_id = rbd_dev->dev_id;
4428 spin_unlock(&rbd_dev_list_lock);
4431 * The max id could have been updated by rbd_dev_id_get(), in
4432 * which case it now accurately reflects the new maximum.
4433 * Be careful not to overwrite the maximum value in that
4436 atomic64_cmpxchg(&rbd_dev_id_max, rbd_id, max_id);
4437 dout(" max dev id has been reset\n");
4441 * Skips over white space at *buf, and updates *buf to point to the
4442 * first found non-space character (if any). Returns the length of
4443 * the token (string of non-white space characters) found. Note
4444 * that *buf must be terminated with '\0'.
4446 static inline size_t next_token(const char **buf)
4449 * These are the characters that produce nonzero for
4450 * isspace() in the "C" and "POSIX" locales.
4452 const char *spaces = " \f\n\r\t\v";
4454 *buf += strspn(*buf, spaces); /* Find start of token */
4456 return strcspn(*buf, spaces); /* Return token length */
4460 * Finds the next token in *buf, and if the provided token buffer is
4461 * big enough, copies the found token into it. The result, if
4462 * copied, is guaranteed to be terminated with '\0'. Note that *buf
4463 * must be terminated with '\0' on entry.
4465 * Returns the length of the token found (not including the '\0').
4466 * Return value will be 0 if no token is found, and it will be >=
4467 * token_size if the token would not fit.
4469 * The *buf pointer will be updated to point beyond the end of the
4470 * found token. Note that this occurs even if the token buffer is
4471 * too small to hold it.
4473 static inline size_t copy_token(const char **buf,
4479 len = next_token(buf);
4480 if (len < token_size) {
4481 memcpy(token, *buf, len);
4482 *(token + len) = '\0';
4490 * Finds the next token in *buf, dynamically allocates a buffer big
4491 * enough to hold a copy of it, and copies the token into the new
4492 * buffer. The copy is guaranteed to be terminated with '\0'. Note
4493 * that a duplicate buffer is created even for a zero-length token.
4495 * Returns a pointer to the newly-allocated duplicate, or a null
4496 * pointer if memory for the duplicate was not available. If
4497 * the lenp argument is a non-null pointer, the length of the token
4498 * (not including the '\0') is returned in *lenp.
4500 * If successful, the *buf pointer will be updated to point beyond
4501 * the end of the found token.
4503 * Note: uses GFP_KERNEL for allocation.
4505 static inline char *dup_token(const char **buf, size_t *lenp)
4510 len = next_token(buf);
4511 dup = kmemdup(*buf, len + 1, GFP_KERNEL);
4514 *(dup + len) = '\0';
4524 * Parse the options provided for an "rbd add" (i.e., rbd image
4525 * mapping) request. These arrive via a write to /sys/bus/rbd/add,
4526 * and the data written is passed here via a NUL-terminated buffer.
4527 * Returns 0 if successful or an error code otherwise.
4529 * The information extracted from these options is recorded in
4530 * the other parameters which return dynamically-allocated
4533 * The address of a pointer that will refer to a ceph options
4534 * structure. Caller must release the returned pointer using
4535 * ceph_destroy_options() when it is no longer needed.
4537 * Address of an rbd options pointer. Fully initialized by
4538 * this function; caller must release with kfree().
4540 * Address of an rbd image specification pointer. Fully
4541 * initialized by this function based on parsed options.
4542 * Caller must release with rbd_spec_put().
4544 * The options passed take this form:
4545 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
4548 * A comma-separated list of one or more monitor addresses.
4549 * A monitor address is an ip address, optionally followed
4550 * by a port number (separated by a colon).
4551 * I.e.: ip1[:port1][,ip2[:port2]...]
4553 * A comma-separated list of ceph and/or rbd options.
4555 * The name of the rados pool containing the rbd image.
4557 * The name of the image in that pool to map.
4559 * An optional snapshot id. If provided, the mapping will
4560 * present data from the image at the time that snapshot was
4561 * created. The image head is used if no snapshot id is
4562 * provided. Snapshot mappings are always read-only.
4564 static int rbd_add_parse_args(const char *buf,
4565 struct ceph_options **ceph_opts,
4566 struct rbd_options **opts,
4567 struct rbd_spec **rbd_spec)
4571 const char *mon_addrs;
4573 size_t mon_addrs_size;
4574 struct rbd_spec *spec = NULL;
4575 struct rbd_options *rbd_opts = NULL;
4576 struct ceph_options *copts;
4579 /* The first four tokens are required */
4581 len = next_token(&buf);
4583 rbd_warn(NULL, "no monitor address(es) provided");
4587 mon_addrs_size = len + 1;
4591 options = dup_token(&buf, NULL);
4595 rbd_warn(NULL, "no options provided");
4599 spec = rbd_spec_alloc();
4603 spec->pool_name = dup_token(&buf, NULL);
4604 if (!spec->pool_name)
4606 if (!*spec->pool_name) {
4607 rbd_warn(NULL, "no pool name provided");
4611 spec->image_name = dup_token(&buf, NULL);
4612 if (!spec->image_name)
4614 if (!*spec->image_name) {
4615 rbd_warn(NULL, "no image name provided");
4620 * Snapshot name is optional; default is to use "-"
4621 * (indicating the head/no snapshot).
4623 len = next_token(&buf);
4625 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
4626 len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
4627 } else if (len > RBD_MAX_SNAP_NAME_LEN) {
4628 ret = -ENAMETOOLONG;
4631 snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
4634 *(snap_name + len) = '\0';
4635 spec->snap_name = snap_name;
4637 /* Initialize all rbd options to the defaults */
4639 rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL);
4643 rbd_opts->read_only = RBD_READ_ONLY_DEFAULT;
4645 copts = ceph_parse_options(options, mon_addrs,
4646 mon_addrs + mon_addrs_size - 1,
4647 parse_rbd_opts_token, rbd_opts);
4648 if (IS_ERR(copts)) {
4649 ret = PTR_ERR(copts);
4670 * An rbd format 2 image has a unique identifier, distinct from the
4671 * name given to it by the user. Internally, that identifier is
4672 * what's used to specify the names of objects related to the image.
4674 * A special "rbd id" object is used to map an rbd image name to its
4675 * id. If that object doesn't exist, then there is no v2 rbd image
4676 * with the supplied name.
4678 * This function will record the given rbd_dev's image_id field if
4679 * it can be determined, and in that case will return 0. If any
4680 * errors occur a negative errno will be returned and the rbd_dev's
4681 * image_id field will be unchanged (and should be NULL).
4683 static int rbd_dev_image_id(struct rbd_device *rbd_dev)
4692 * When probing a parent image, the image id is already
4693 * known (and the image name likely is not). There's no
4694 * need to fetch the image id again in this case. We
4695 * do still need to set the image format though.
4697 if (rbd_dev->spec->image_id) {
4698 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;
4704 * First, see if the format 2 image id file exists, and if
4705 * so, get the image's persistent id from it.
4707 size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name);
4708 object_name = kmalloc(size, GFP_NOIO);
4711 sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name);
4712 dout("rbd id object name is %s\n", object_name);
4714 /* Response will be an encoded string, which includes a length */
4716 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
4717 response = kzalloc(size, GFP_NOIO);
4723 /* If it doesn't exist we'll assume it's a format 1 image */
4725 ret = rbd_obj_method_sync(rbd_dev, object_name,
4726 "rbd", "get_id", NULL, 0,
4727 response, RBD_IMAGE_ID_LEN_MAX);
4728 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4729 if (ret == -ENOENT) {
4730 image_id = kstrdup("", GFP_KERNEL);
4731 ret = image_id ? 0 : -ENOMEM;
4733 rbd_dev->image_format = 1;
4734 } else if (ret > sizeof (__le32)) {
4737 image_id = ceph_extract_encoded_string(&p, p + ret,
4739 ret = IS_ERR(image_id) ? PTR_ERR(image_id) : 0;
4741 rbd_dev->image_format = 2;
4747 rbd_dev->spec->image_id = image_id;
4748 dout("image_id is %s\n", image_id);
4758 * Undo whatever state changes are made by v1 or v2 header info
4761 static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
4763 struct rbd_image_header *header;
4765 /* Drop parent reference unless it's already been done (or none) */
4767 if (rbd_dev->parent_overlap)
4768 rbd_dev_parent_put(rbd_dev);
4770 /* Free dynamic fields from the header, then zero it out */
4772 header = &rbd_dev->header;
4773 ceph_put_snap_context(header->snapc);
4774 kfree(header->snap_sizes);
4775 kfree(header->snap_names);
4776 kfree(header->object_prefix);
4777 memset(header, 0, sizeof (*header));
4780 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev)
4784 ret = rbd_dev_v2_object_prefix(rbd_dev);
4789 * Get the and check features for the image. Currently the
4790 * features are assumed to never change.
4792 ret = rbd_dev_v2_features(rbd_dev);
4796 /* If the image supports fancy striping, get its parameters */
4798 if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
4799 ret = rbd_dev_v2_striping_info(rbd_dev);
4803 /* No support for crypto and compression type format 2 images */
4807 rbd_dev->header.features = 0;
4808 kfree(rbd_dev->header.object_prefix);
4809 rbd_dev->header.object_prefix = NULL;
4814 static int rbd_dev_probe_parent(struct rbd_device *rbd_dev)
4816 struct rbd_device *parent = NULL;
4817 struct rbd_spec *parent_spec;
4818 struct rbd_client *rbdc;
4821 if (!rbd_dev->parent_spec)
4824 * We need to pass a reference to the client and the parent
4825 * spec when creating the parent rbd_dev. Images related by
4826 * parent/child relationships always share both.
4828 parent_spec = rbd_spec_get(rbd_dev->parent_spec);
4829 rbdc = __rbd_get_client(rbd_dev->rbd_client);
4832 parent = rbd_dev_create(rbdc, parent_spec);
4836 ret = rbd_dev_image_probe(parent, false);
4839 rbd_dev->parent = parent;
4840 atomic_set(&rbd_dev->parent_ref, 1);
4845 rbd_dev_unparent(rbd_dev);
4846 kfree(rbd_dev->header_name);
4847 rbd_dev_destroy(parent);
4849 rbd_put_client(rbdc);
4850 rbd_spec_put(parent_spec);
4856 static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
4860 /* generate unique id: find highest unique id, add one */
4861 rbd_dev_id_get(rbd_dev);
4863 /* Fill in the device name, now that we have its id. */
4864 BUILD_BUG_ON(DEV_NAME_LEN
4865 < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
4866 sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id);
4868 /* Get our block major device number. */
4870 ret = register_blkdev(0, rbd_dev->name);
4873 rbd_dev->major = ret;
4875 /* Set up the blkdev mapping. */
4877 ret = rbd_init_disk(rbd_dev);
4879 goto err_out_blkdev;
4881 ret = rbd_dev_mapping_set(rbd_dev);
4884 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
4886 ret = rbd_bus_add_dev(rbd_dev);
4888 goto err_out_mapping;
4890 /* Everything's ready. Announce the disk to the world. */
4892 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
4893 add_disk(rbd_dev->disk);
4895 pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name,
4896 (unsigned long long) rbd_dev->mapping.size);
4901 rbd_dev_mapping_clear(rbd_dev);
4903 rbd_free_disk(rbd_dev);
4905 unregister_blkdev(rbd_dev->major, rbd_dev->name);
4907 rbd_dev_id_put(rbd_dev);
4908 rbd_dev_mapping_clear(rbd_dev);
4913 static int rbd_dev_header_name(struct rbd_device *rbd_dev)
4915 struct rbd_spec *spec = rbd_dev->spec;
4918 /* Record the header object name for this rbd image. */
4920 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
4922 if (rbd_dev->image_format == 1)
4923 size = strlen(spec->image_name) + sizeof (RBD_SUFFIX);
4925 size = sizeof (RBD_HEADER_PREFIX) + strlen(spec->image_id);
4927 rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
4928 if (!rbd_dev->header_name)
4931 if (rbd_dev->image_format == 1)
4932 sprintf(rbd_dev->header_name, "%s%s",
4933 spec->image_name, RBD_SUFFIX);
4935 sprintf(rbd_dev->header_name, "%s%s",
4936 RBD_HEADER_PREFIX, spec->image_id);
4940 static void rbd_dev_image_release(struct rbd_device *rbd_dev)
4942 rbd_dev_unprobe(rbd_dev);
4943 kfree(rbd_dev->header_name);
4944 rbd_dev->header_name = NULL;
4945 rbd_dev->image_format = 0;
4946 kfree(rbd_dev->spec->image_id);
4947 rbd_dev->spec->image_id = NULL;
4949 rbd_dev_destroy(rbd_dev);
4953 * Probe for the existence of the header object for the given rbd
4954 * device. If this image is the one being mapped (i.e., not a
4955 * parent), initiate a watch on its header object before using that
4956 * object to get detailed information about the rbd image.
4958 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping)
4964 * Get the id from the image id object. Unless there's an
4965 * error, rbd_dev->spec->image_id will be filled in with
4966 * a dynamically-allocated string, and rbd_dev->image_format
4967 * will be set to either 1 or 2.
4969 ret = rbd_dev_image_id(rbd_dev);
4972 rbd_assert(rbd_dev->spec->image_id);
4973 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
4975 ret = rbd_dev_header_name(rbd_dev);
4977 goto err_out_format;
4980 ret = rbd_dev_header_watch_sync(rbd_dev, true);
4982 goto out_header_name;
4985 if (rbd_dev->image_format == 1)
4986 ret = rbd_dev_v1_header_info(rbd_dev);
4988 ret = rbd_dev_v2_header_info(rbd_dev);
4992 ret = rbd_dev_spec_update(rbd_dev);
4996 ret = rbd_dev_probe_parent(rbd_dev);
5000 dout("discovered format %u image, header name is %s\n",
5001 rbd_dev->image_format, rbd_dev->header_name);
5005 rbd_dev_unprobe(rbd_dev);
5008 tmp = rbd_dev_header_watch_sync(rbd_dev, false);
5010 rbd_warn(rbd_dev, "unable to tear down "
5011 "watch request (%d)\n", tmp);
5014 kfree(rbd_dev->header_name);
5015 rbd_dev->header_name = NULL;
5017 rbd_dev->image_format = 0;
5018 kfree(rbd_dev->spec->image_id);
5019 rbd_dev->spec->image_id = NULL;
5021 dout("probe failed, returning %d\n", ret);
5026 static ssize_t rbd_add(struct bus_type *bus,
5030 struct rbd_device *rbd_dev = NULL;
5031 struct ceph_options *ceph_opts = NULL;
5032 struct rbd_options *rbd_opts = NULL;
5033 struct rbd_spec *spec = NULL;
5034 struct rbd_client *rbdc;
5035 struct ceph_osd_client *osdc;
5039 if (!try_module_get(THIS_MODULE))
5042 /* parse add command */
5043 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
5045 goto err_out_module;
5046 read_only = rbd_opts->read_only;
5048 rbd_opts = NULL; /* done with this */
5050 rbdc = rbd_get_client(ceph_opts);
5057 osdc = &rbdc->client->osdc;
5058 rc = ceph_pg_poolid_by_name(osdc->osdmap, spec->pool_name);
5060 goto err_out_client;
5061 spec->pool_id = (u64)rc;
5063 /* The ceph file layout needs to fit pool id in 32 bits */
5065 if (spec->pool_id > (u64)U32_MAX) {
5066 rbd_warn(NULL, "pool id too large (%llu > %u)\n",
5067 (unsigned long long)spec->pool_id, U32_MAX);
5069 goto err_out_client;
5072 rbd_dev = rbd_dev_create(rbdc, spec);
5074 goto err_out_client;
5075 rbdc = NULL; /* rbd_dev now owns this */
5076 spec = NULL; /* rbd_dev now owns this */
5078 rc = rbd_dev_image_probe(rbd_dev, true);
5080 goto err_out_rbd_dev;
5082 /* If we are mapping a snapshot it must be marked read-only */
5084 if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
5086 rbd_dev->mapping.read_only = read_only;
5088 rc = rbd_dev_device_setup(rbd_dev);
5090 rbd_dev_image_release(rbd_dev);
5091 goto err_out_module;
5097 rbd_dev_destroy(rbd_dev);
5099 rbd_put_client(rbdc);
5103 module_put(THIS_MODULE);
5105 dout("Error adding device %s\n", buf);
5110 static void rbd_dev_device_release(struct device *dev)
5112 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5114 rbd_free_disk(rbd_dev);
5115 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
5116 rbd_dev_mapping_clear(rbd_dev);
5117 unregister_blkdev(rbd_dev->major, rbd_dev->name);
5119 rbd_dev_id_put(rbd_dev);
5120 rbd_dev_mapping_clear(rbd_dev);
5123 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
5125 while (rbd_dev->parent) {
5126 struct rbd_device *first = rbd_dev;
5127 struct rbd_device *second = first->parent;
5128 struct rbd_device *third;
5131 * Follow to the parent with no grandparent and
5134 while (second && (third = second->parent)) {
5139 rbd_dev_image_release(second);
5140 first->parent = NULL;
5141 first->parent_overlap = 0;
5143 rbd_assert(first->parent_spec);
5144 rbd_spec_put(first->parent_spec);
5145 first->parent_spec = NULL;
5149 static ssize_t rbd_remove(struct bus_type *bus,
5153 struct rbd_device *rbd_dev = NULL;
5154 struct list_head *tmp;
5157 bool already = false;
5160 ret = strict_strtoul(buf, 10, &ul);
5164 /* convert to int; abort if we lost anything in the conversion */
5169 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
5172 spin_lock(&rbd_dev_list_lock);
5173 list_for_each(tmp, &rbd_dev_list) {
5174 rbd_dev = list_entry(tmp, struct rbd_device, node);
5175 if (rbd_dev->dev_id == dev_id) {
5181 spin_lock_irq(&rbd_dev->lock);
5182 if (rbd_dev->open_count)
5185 already = test_and_set_bit(RBD_DEV_FLAG_REMOVING,
5187 spin_unlock_irq(&rbd_dev->lock);
5189 spin_unlock(&rbd_dev_list_lock);
5190 if (ret < 0 || already)
5193 ret = rbd_dev_header_watch_sync(rbd_dev, false);
5195 rbd_warn(rbd_dev, "failed to cancel watch event (%d)\n", ret);
5198 * flush remaining watch callbacks - these must be complete
5199 * before the osd_client is shutdown
5201 dout("%s: flushing notifies", __func__);
5202 ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc);
5204 * Don't free anything from rbd_dev->disk until after all
5205 * notifies are completely processed. Otherwise
5206 * rbd_bus_del_dev() will race with rbd_watch_cb(), resulting
5207 * in a potential use after free of rbd_dev->disk or rbd_dev.
5209 rbd_bus_del_dev(rbd_dev);
5210 rbd_dev_image_release(rbd_dev);
5211 module_put(THIS_MODULE);
5214 mutex_unlock(&ctl_mutex);
5220 * create control files in sysfs
5223 static int rbd_sysfs_init(void)
5227 ret = device_register(&rbd_root_dev);
5231 ret = bus_register(&rbd_bus_type);
5233 device_unregister(&rbd_root_dev);
5238 static void rbd_sysfs_cleanup(void)
5240 bus_unregister(&rbd_bus_type);
5241 device_unregister(&rbd_root_dev);
5244 static int rbd_slab_init(void)
5246 rbd_assert(!rbd_img_request_cache);
5247 rbd_img_request_cache = kmem_cache_create("rbd_img_request",
5248 sizeof (struct rbd_img_request),
5249 __alignof__(struct rbd_img_request),
5251 if (!rbd_img_request_cache)
5254 rbd_assert(!rbd_obj_request_cache);
5255 rbd_obj_request_cache = kmem_cache_create("rbd_obj_request",
5256 sizeof (struct rbd_obj_request),
5257 __alignof__(struct rbd_obj_request),
5259 if (!rbd_obj_request_cache)
5262 rbd_assert(!rbd_segment_name_cache);
5263 rbd_segment_name_cache = kmem_cache_create("rbd_segment_name",
5264 MAX_OBJ_NAME_SIZE + 1, 1, 0, NULL);
5265 if (rbd_segment_name_cache)
5268 if (rbd_obj_request_cache) {
5269 kmem_cache_destroy(rbd_obj_request_cache);
5270 rbd_obj_request_cache = NULL;
5273 kmem_cache_destroy(rbd_img_request_cache);
5274 rbd_img_request_cache = NULL;
5279 static void rbd_slab_exit(void)
5281 rbd_assert(rbd_segment_name_cache);
5282 kmem_cache_destroy(rbd_segment_name_cache);
5283 rbd_segment_name_cache = NULL;
5285 rbd_assert(rbd_obj_request_cache);
5286 kmem_cache_destroy(rbd_obj_request_cache);
5287 rbd_obj_request_cache = NULL;
5289 rbd_assert(rbd_img_request_cache);
5290 kmem_cache_destroy(rbd_img_request_cache);
5291 rbd_img_request_cache = NULL;
5294 static int __init rbd_init(void)
5298 if (!libceph_compatible(NULL)) {
5299 rbd_warn(NULL, "libceph incompatibility (quitting)");
5303 rc = rbd_slab_init();
5306 rc = rbd_sysfs_init();
5310 pr_info("loaded " RBD_DRV_NAME_LONG "\n");
5315 static void __exit rbd_exit(void)
5317 rbd_sysfs_cleanup();
5321 module_init(rbd_init);
5322 module_exit(rbd_exit);
5324 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
5325 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
5326 MODULE_DESCRIPTION("rados block device");
5328 /* following authorship retained from original osdblk.c */
5329 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
5331 MODULE_LICENSE("GPL");