2 rbd.c -- Export ceph rados objects as a Linux block device
5 based on drivers/block/osdblk.c:
7 Copyright 2009 Red Hat, Inc.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; see the file COPYING. If not, write to
20 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
24 For usage instructions, please refer to:
26 Documentation/ABI/testing/sysfs-bus-rbd
30 #include <linux/ceph/libceph.h>
31 #include <linux/ceph/osd_client.h>
32 #include <linux/ceph/mon_client.h>
33 #include <linux/ceph/decode.h>
34 #include <linux/parser.h>
36 #include <linux/kernel.h>
37 #include <linux/device.h>
38 #include <linux/module.h>
40 #include <linux/blkdev.h>
42 #include "rbd_types.h"
44 #define RBD_DEBUG /* Activate rbd_assert() calls */
47 * The basic unit of block I/O is a sector. It is interpreted in a
48 * number of contexts in Linux (blk, bio, genhd), but the default is
49 * universally 512 bytes. These symbols are just slightly more
50 * meaningful than the bare numbers they represent.
52 #define SECTOR_SHIFT 9
53 #define SECTOR_SIZE (1ULL << SECTOR_SHIFT)
55 #define RBD_DRV_NAME "rbd"
56 #define RBD_DRV_NAME_LONG "rbd (rados block device)"
58 #define RBD_MINORS_PER_MAJOR 256 /* max minors per blkdev */
60 #define RBD_SNAP_DEV_NAME_PREFIX "snap_"
61 #define RBD_MAX_SNAP_NAME_LEN \
62 (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1))
64 #define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */
66 #define RBD_SNAP_HEAD_NAME "-"
68 /* This allows a single page to hold an image name sent by OSD */
69 #define RBD_IMAGE_NAME_LEN_MAX (PAGE_SIZE - sizeof (__le32) - 1)
70 #define RBD_IMAGE_ID_LEN_MAX 64
72 #define RBD_OBJ_PREFIX_LEN_MAX 64
76 #define RBD_FEATURE_LAYERING (1<<0)
77 #define RBD_FEATURE_STRIPINGV2 (1<<1)
78 #define RBD_FEATURES_ALL \
79 (RBD_FEATURE_LAYERING | RBD_FEATURE_STRIPINGV2)
81 /* Features supported by this (client software) implementation. */
83 #define RBD_FEATURES_SUPPORTED (0)
86 * An RBD device name will be "rbd#", where the "rbd" comes from
87 * RBD_DRV_NAME above, and # is a unique integer identifier.
88 * MAX_INT_FORMAT_WIDTH is used in ensuring DEV_NAME_LEN is big
89 * enough to hold all possible device names.
91 #define DEV_NAME_LEN 32
92 #define MAX_INT_FORMAT_WIDTH ((5 * sizeof (int)) / 2 + 1)
95 * block device image metadata (in-memory version)
97 struct rbd_image_header {
98 /* These four fields never change for a given rbd image */
105 /* The remaining fields need to be updated occasionally */
107 struct ceph_snap_context *snapc;
115 * An rbd image specification.
117 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely
118 * identify an image. Each rbd_dev structure includes a pointer to
119 * an rbd_spec structure that encapsulates this identity.
121 * Each of the id's in an rbd_spec has an associated name. For a
122 * user-mapped image, the names are supplied and the id's associated
123 * with them are looked up. For a layered image, a parent image is
124 * defined by the tuple, and the names are looked up.
126 * An rbd_dev structure contains a parent_spec pointer which is
127 * non-null if the image it represents is a child in a layered
128 * image. This pointer will refer to the rbd_spec structure used
129 * by the parent rbd_dev for its own identity (i.e., the structure
130 * is shared between the parent and child).
132 * Since these structures are populated once, during the discovery
133 * phase of image construction, they are effectively immutable so
134 * we make no effort to synchronize access to them.
136 * Note that code herein does not assume the image name is known (it
137 * could be a null pointer).
153 * an instance of the client. multiple devices may share an rbd client.
156 struct ceph_client *client;
158 struct list_head node;
161 struct rbd_img_request;
162 typedef void (*rbd_img_callback_t)(struct rbd_img_request *);
164 #define BAD_WHICH U32_MAX /* Good which or bad which, which? */
166 struct rbd_obj_request;
167 typedef void (*rbd_obj_callback_t)(struct rbd_obj_request *);
169 enum obj_request_type {
170 OBJ_REQUEST_NODATA, OBJ_REQUEST_BIO, OBJ_REQUEST_PAGES
174 OBJ_REQ_DONE, /* completion flag: not done = 0, done = 1 */
175 OBJ_REQ_IMG_DATA, /* object usage: standalone = 0, image = 1 */
178 struct rbd_obj_request {
179 const char *object_name;
180 u64 offset; /* object start byte */
181 u64 length; /* bytes from offset */
184 struct rbd_img_request *img_request;
185 u64 img_offset; /* image relative offset */
186 struct list_head links; /* img_request->obj_requests */
187 u32 which; /* posn image request list */
189 enum obj_request_type type;
191 struct bio *bio_list;
198 struct ceph_osd_request *osd_req;
200 u64 xferred; /* bytes transferred */
204 rbd_obj_callback_t callback;
205 struct completion completion;
211 IMG_REQ_WRITE, /* I/O direction: read = 0, write = 1 */
212 IMG_REQ_CHILD, /* initiator: block = 0, child image = 1 */
213 IMG_REQ_LAYERED, /* ENOENT handling: normal = 0, layered = 1 */
216 struct rbd_img_request {
217 struct rbd_device *rbd_dev;
218 u64 offset; /* starting image byte offset */
219 u64 length; /* byte count from offset */
222 u64 snap_id; /* for reads */
223 struct ceph_snap_context *snapc; /* for writes */
226 struct request *rq; /* block request */
227 struct rbd_obj_request *obj_request; /* obj req initiator */
229 spinlock_t completion_lock;/* protects next_completion */
231 rbd_img_callback_t callback;
232 u64 xferred;/* aggregate bytes transferred */
233 int result; /* first nonzero obj_request result */
235 u32 obj_request_count;
236 struct list_head obj_requests; /* rbd_obj_request structs */
241 #define for_each_obj_request(ireq, oreq) \
242 list_for_each_entry(oreq, &(ireq)->obj_requests, links)
243 #define for_each_obj_request_from(ireq, oreq) \
244 list_for_each_entry_from(oreq, &(ireq)->obj_requests, links)
245 #define for_each_obj_request_safe(ireq, oreq, n) \
246 list_for_each_entry_safe_reverse(oreq, n, &(ireq)->obj_requests, links)
252 struct list_head node;
267 int dev_id; /* blkdev unique id */
269 int major; /* blkdev assigned major */
270 struct gendisk *disk; /* blkdev's gendisk and rq */
272 u32 image_format; /* Either 1 or 2 */
273 struct rbd_client *rbd_client;
275 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */
277 spinlock_t lock; /* queue, flags, open_count */
279 struct rbd_image_header header;
280 unsigned long flags; /* possibly lock protected */
281 struct rbd_spec *spec;
285 struct ceph_file_layout layout;
287 struct ceph_osd_event *watch_event;
288 struct rbd_obj_request *watch_request;
290 struct rbd_spec *parent_spec;
292 struct rbd_device *parent;
294 /* protects updating the header */
295 struct rw_semaphore header_rwsem;
297 struct rbd_mapping mapping;
299 struct list_head node;
301 /* list of snapshots */
302 struct list_head snaps;
306 unsigned long open_count; /* protected by lock */
310 * Flag bits for rbd_dev->flags. If atomicity is required,
311 * rbd_dev->lock is used to protect access.
313 * Currently, only the "removing" flag (which is coupled with the
314 * "open_count" field) requires atomic access.
317 RBD_DEV_FLAG_EXISTS, /* mapped snapshot has not been deleted */
318 RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */
321 static DEFINE_MUTEX(ctl_mutex); /* Serialize open/close/setup/teardown */
323 static LIST_HEAD(rbd_dev_list); /* devices */
324 static DEFINE_SPINLOCK(rbd_dev_list_lock);
326 static LIST_HEAD(rbd_client_list); /* clients */
327 static DEFINE_SPINLOCK(rbd_client_list_lock);
329 static int rbd_dev_snaps_update(struct rbd_device *rbd_dev);
330 static int rbd_dev_snaps_register(struct rbd_device *rbd_dev);
332 static void rbd_dev_release(struct device *dev);
333 static void rbd_remove_snap_dev(struct rbd_snap *snap);
335 static ssize_t rbd_add(struct bus_type *bus, const char *buf,
337 static ssize_t rbd_remove(struct bus_type *bus, const char *buf,
339 static int rbd_dev_probe(struct rbd_device *rbd_dev);
341 static struct bus_attribute rbd_bus_attrs[] = {
342 __ATTR(add, S_IWUSR, NULL, rbd_add),
343 __ATTR(remove, S_IWUSR, NULL, rbd_remove),
347 static struct bus_type rbd_bus_type = {
349 .bus_attrs = rbd_bus_attrs,
352 static void rbd_root_dev_release(struct device *dev)
356 static struct device rbd_root_dev = {
358 .release = rbd_root_dev_release,
361 static __printf(2, 3)
362 void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...)
364 struct va_format vaf;
372 printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf);
373 else if (rbd_dev->disk)
374 printk(KERN_WARNING "%s: %s: %pV\n",
375 RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf);
376 else if (rbd_dev->spec && rbd_dev->spec->image_name)
377 printk(KERN_WARNING "%s: image %s: %pV\n",
378 RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf);
379 else if (rbd_dev->spec && rbd_dev->spec->image_id)
380 printk(KERN_WARNING "%s: id %s: %pV\n",
381 RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf);
383 printk(KERN_WARNING "%s: rbd_dev %p: %pV\n",
384 RBD_DRV_NAME, rbd_dev, &vaf);
389 #define rbd_assert(expr) \
390 if (unlikely(!(expr))) { \
391 printk(KERN_ERR "\nAssertion failure in %s() " \
393 "\trbd_assert(%s);\n\n", \
394 __func__, __LINE__, #expr); \
397 #else /* !RBD_DEBUG */
398 # define rbd_assert(expr) ((void) 0)
399 #endif /* !RBD_DEBUG */
401 static void rbd_img_parent_read(struct rbd_obj_request *obj_request);
403 static int rbd_dev_refresh(struct rbd_device *rbd_dev, u64 *hver);
404 static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev, u64 *hver);
406 static int rbd_open(struct block_device *bdev, fmode_t mode)
408 struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
409 bool removing = false;
411 if ((mode & FMODE_WRITE) && rbd_dev->mapping.read_only)
414 spin_lock_irq(&rbd_dev->lock);
415 if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags))
418 rbd_dev->open_count++;
419 spin_unlock_irq(&rbd_dev->lock);
423 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
424 (void) get_device(&rbd_dev->dev);
425 set_device_ro(bdev, rbd_dev->mapping.read_only);
426 mutex_unlock(&ctl_mutex);
431 static int rbd_release(struct gendisk *disk, fmode_t mode)
433 struct rbd_device *rbd_dev = disk->private_data;
434 unsigned long open_count_before;
436 spin_lock_irq(&rbd_dev->lock);
437 open_count_before = rbd_dev->open_count--;
438 spin_unlock_irq(&rbd_dev->lock);
439 rbd_assert(open_count_before > 0);
441 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
442 put_device(&rbd_dev->dev);
443 mutex_unlock(&ctl_mutex);
448 static const struct block_device_operations rbd_bd_ops = {
449 .owner = THIS_MODULE,
451 .release = rbd_release,
455 * Initialize an rbd client instance.
458 static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
460 struct rbd_client *rbdc;
463 dout("%s:\n", __func__);
464 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
468 kref_init(&rbdc->kref);
469 INIT_LIST_HEAD(&rbdc->node);
471 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
473 rbdc->client = ceph_create_client(ceph_opts, rbdc, 0, 0);
474 if (IS_ERR(rbdc->client))
476 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
478 ret = ceph_open_session(rbdc->client);
482 spin_lock(&rbd_client_list_lock);
483 list_add_tail(&rbdc->node, &rbd_client_list);
484 spin_unlock(&rbd_client_list_lock);
486 mutex_unlock(&ctl_mutex);
487 dout("%s: rbdc %p\n", __func__, rbdc);
492 ceph_destroy_client(rbdc->client);
494 mutex_unlock(&ctl_mutex);
498 ceph_destroy_options(ceph_opts);
499 dout("%s: error %d\n", __func__, ret);
504 static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
506 kref_get(&rbdc->kref);
512 * Find a ceph client with specific addr and configuration. If
513 * found, bump its reference count.
515 static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
517 struct rbd_client *client_node;
520 if (ceph_opts->flags & CEPH_OPT_NOSHARE)
523 spin_lock(&rbd_client_list_lock);
524 list_for_each_entry(client_node, &rbd_client_list, node) {
525 if (!ceph_compare_options(ceph_opts, client_node->client)) {
526 __rbd_get_client(client_node);
532 spin_unlock(&rbd_client_list_lock);
534 return found ? client_node : NULL;
544 /* string args above */
547 /* Boolean args above */
551 static match_table_t rbd_opts_tokens = {
553 /* string args above */
554 {Opt_read_only, "read_only"},
555 {Opt_read_only, "ro"}, /* Alternate spelling */
556 {Opt_read_write, "read_write"},
557 {Opt_read_write, "rw"}, /* Alternate spelling */
558 /* Boolean args above */
566 #define RBD_READ_ONLY_DEFAULT false
568 static int parse_rbd_opts_token(char *c, void *private)
570 struct rbd_options *rbd_opts = private;
571 substring_t argstr[MAX_OPT_ARGS];
572 int token, intval, ret;
574 token = match_token(c, rbd_opts_tokens, argstr);
578 if (token < Opt_last_int) {
579 ret = match_int(&argstr[0], &intval);
581 pr_err("bad mount option arg (not int) "
585 dout("got int token %d val %d\n", token, intval);
586 } else if (token > Opt_last_int && token < Opt_last_string) {
587 dout("got string token %d val %s\n", token,
589 } else if (token > Opt_last_string && token < Opt_last_bool) {
590 dout("got Boolean token %d\n", token);
592 dout("got token %d\n", token);
597 rbd_opts->read_only = true;
600 rbd_opts->read_only = false;
610 * Get a ceph client with specific addr and configuration, if one does
611 * not exist create it.
613 static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
615 struct rbd_client *rbdc;
617 rbdc = rbd_client_find(ceph_opts);
618 if (rbdc) /* using an existing client */
619 ceph_destroy_options(ceph_opts);
621 rbdc = rbd_client_create(ceph_opts);
627 * Destroy ceph client
629 * Caller must hold rbd_client_list_lock.
631 static void rbd_client_release(struct kref *kref)
633 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
635 dout("%s: rbdc %p\n", __func__, rbdc);
636 spin_lock(&rbd_client_list_lock);
637 list_del(&rbdc->node);
638 spin_unlock(&rbd_client_list_lock);
640 ceph_destroy_client(rbdc->client);
645 * Drop reference to ceph client node. If it's not referenced anymore, release
648 static void rbd_put_client(struct rbd_client *rbdc)
651 kref_put(&rbdc->kref, rbd_client_release);
654 static bool rbd_image_format_valid(u32 image_format)
656 return image_format == 1 || image_format == 2;
659 static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
664 /* The header has to start with the magic rbd header text */
665 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
668 /* The bio layer requires at least sector-sized I/O */
670 if (ondisk->options.order < SECTOR_SHIFT)
673 /* If we use u64 in a few spots we may be able to loosen this */
675 if (ondisk->options.order > 8 * sizeof (int) - 1)
679 * The size of a snapshot header has to fit in a size_t, and
680 * that limits the number of snapshots.
682 snap_count = le32_to_cpu(ondisk->snap_count);
683 size = SIZE_MAX - sizeof (struct ceph_snap_context);
684 if (snap_count > size / sizeof (__le64))
688 * Not only that, but the size of the entire the snapshot
689 * header must also be representable in a size_t.
691 size -= snap_count * sizeof (__le64);
692 if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
699 * Create a new header structure, translate header format from the on-disk
702 static int rbd_header_from_disk(struct rbd_image_header *header,
703 struct rbd_image_header_ondisk *ondisk)
710 memset(header, 0, sizeof (*header));
712 snap_count = le32_to_cpu(ondisk->snap_count);
714 len = strnlen(ondisk->object_prefix, sizeof (ondisk->object_prefix));
715 header->object_prefix = kmalloc(len + 1, GFP_KERNEL);
716 if (!header->object_prefix)
718 memcpy(header->object_prefix, ondisk->object_prefix, len);
719 header->object_prefix[len] = '\0';
722 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);
724 /* Save a copy of the snapshot names */
726 if (snap_names_len > (u64) SIZE_MAX)
728 header->snap_names = kmalloc(snap_names_len, GFP_KERNEL);
729 if (!header->snap_names)
732 * Note that rbd_dev_v1_header_read() guarantees
733 * the ondisk buffer we're working with has
734 * snap_names_len bytes beyond the end of the
735 * snapshot id array, this memcpy() is safe.
737 memcpy(header->snap_names, &ondisk->snaps[snap_count],
740 /* Record each snapshot's size */
742 size = snap_count * sizeof (*header->snap_sizes);
743 header->snap_sizes = kmalloc(size, GFP_KERNEL);
744 if (!header->snap_sizes)
746 for (i = 0; i < snap_count; i++)
747 header->snap_sizes[i] =
748 le64_to_cpu(ondisk->snaps[i].image_size);
750 WARN_ON(ondisk->snap_names_len);
751 header->snap_names = NULL;
752 header->snap_sizes = NULL;
755 header->features = 0; /* No features support in v1 images */
756 header->obj_order = ondisk->options.order;
757 header->crypt_type = ondisk->options.crypt_type;
758 header->comp_type = ondisk->options.comp_type;
760 /* Allocate and fill in the snapshot context */
762 header->image_size = le64_to_cpu(ondisk->image_size);
763 size = sizeof (struct ceph_snap_context);
764 size += snap_count * sizeof (header->snapc->snaps[0]);
765 header->snapc = kzalloc(size, GFP_KERNEL);
769 atomic_set(&header->snapc->nref, 1);
770 header->snapc->seq = le64_to_cpu(ondisk->snap_seq);
771 header->snapc->num_snaps = snap_count;
772 for (i = 0; i < snap_count; i++)
773 header->snapc->snaps[i] =
774 le64_to_cpu(ondisk->snaps[i].id);
779 kfree(header->snap_sizes);
780 header->snap_sizes = NULL;
781 kfree(header->snap_names);
782 header->snap_names = NULL;
783 kfree(header->object_prefix);
784 header->object_prefix = NULL;
789 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
791 struct rbd_snap *snap;
793 if (snap_id == CEPH_NOSNAP)
794 return RBD_SNAP_HEAD_NAME;
796 list_for_each_entry(snap, &rbd_dev->snaps, node)
797 if (snap_id == snap->id)
803 static int snap_by_name(struct rbd_device *rbd_dev, const char *snap_name)
806 struct rbd_snap *snap;
808 list_for_each_entry(snap, &rbd_dev->snaps, node) {
809 if (!strcmp(snap_name, snap->name)) {
810 rbd_dev->spec->snap_id = snap->id;
811 rbd_dev->mapping.size = snap->size;
812 rbd_dev->mapping.features = snap->features;
821 static int rbd_dev_set_mapping(struct rbd_device *rbd_dev)
825 if (!memcmp(rbd_dev->spec->snap_name, RBD_SNAP_HEAD_NAME,
826 sizeof (RBD_SNAP_HEAD_NAME))) {
827 rbd_dev->spec->snap_id = CEPH_NOSNAP;
828 rbd_dev->mapping.size = rbd_dev->header.image_size;
829 rbd_dev->mapping.features = rbd_dev->header.features;
832 ret = snap_by_name(rbd_dev, rbd_dev->spec->snap_name);
835 rbd_dev->mapping.read_only = true;
837 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
843 static void rbd_header_free(struct rbd_image_header *header)
845 kfree(header->object_prefix);
846 header->object_prefix = NULL;
847 kfree(header->snap_sizes);
848 header->snap_sizes = NULL;
849 kfree(header->snap_names);
850 header->snap_names = NULL;
851 ceph_put_snap_context(header->snapc);
852 header->snapc = NULL;
855 static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset)
861 name = kmalloc(MAX_OBJ_NAME_SIZE + 1, GFP_NOIO);
864 segment = offset >> rbd_dev->header.obj_order;
865 ret = snprintf(name, MAX_OBJ_NAME_SIZE + 1, "%s.%012llx",
866 rbd_dev->header.object_prefix, segment);
867 if (ret < 0 || ret > MAX_OBJ_NAME_SIZE) {
868 pr_err("error formatting segment name for #%llu (%d)\n",
877 static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset)
879 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
881 return offset & (segment_size - 1);
884 static u64 rbd_segment_length(struct rbd_device *rbd_dev,
885 u64 offset, u64 length)
887 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
889 offset &= segment_size - 1;
891 rbd_assert(length <= U64_MAX - offset);
892 if (offset + length > segment_size)
893 length = segment_size - offset;
899 * returns the size of an object in the image
901 static u64 rbd_obj_bytes(struct rbd_image_header *header)
903 return 1 << header->obj_order;
910 static void bio_chain_put(struct bio *chain)
916 chain = chain->bi_next;
922 * zeros a bio chain, starting at specific offset
924 static void zero_bio_chain(struct bio *chain, int start_ofs)
933 bio_for_each_segment(bv, chain, i) {
934 if (pos + bv->bv_len > start_ofs) {
935 int remainder = max(start_ofs - pos, 0);
936 buf = bvec_kmap_irq(bv, &flags);
937 memset(buf + remainder, 0,
938 bv->bv_len - remainder);
939 bvec_kunmap_irq(buf, &flags);
944 chain = chain->bi_next;
949 * Clone a portion of a bio, starting at the given byte offset
950 * and continuing for the number of bytes indicated.
952 static struct bio *bio_clone_range(struct bio *bio_src,
961 unsigned short end_idx;
965 /* Handle the easy case for the caller */
967 if (!offset && len == bio_src->bi_size)
968 return bio_clone(bio_src, gfpmask);
970 if (WARN_ON_ONCE(!len))
972 if (WARN_ON_ONCE(len > bio_src->bi_size))
974 if (WARN_ON_ONCE(offset > bio_src->bi_size - len))
977 /* Find first affected segment... */
980 __bio_for_each_segment(bv, bio_src, idx, 0) {
981 if (resid < bv->bv_len)
987 /* ...and the last affected segment */
990 __bio_for_each_segment(bv, bio_src, end_idx, idx) {
991 if (resid <= bv->bv_len)
995 vcnt = end_idx - idx + 1;
997 /* Build the clone */
999 bio = bio_alloc(gfpmask, (unsigned int) vcnt);
1001 return NULL; /* ENOMEM */
1003 bio->bi_bdev = bio_src->bi_bdev;
1004 bio->bi_sector = bio_src->bi_sector + (offset >> SECTOR_SHIFT);
1005 bio->bi_rw = bio_src->bi_rw;
1006 bio->bi_flags |= 1 << BIO_CLONED;
1009 * Copy over our part of the bio_vec, then update the first
1010 * and last (or only) entries.
1012 memcpy(&bio->bi_io_vec[0], &bio_src->bi_io_vec[idx],
1013 vcnt * sizeof (struct bio_vec));
1014 bio->bi_io_vec[0].bv_offset += voff;
1016 bio->bi_io_vec[0].bv_len -= voff;
1017 bio->bi_io_vec[vcnt - 1].bv_len = resid;
1019 bio->bi_io_vec[0].bv_len = len;
1022 bio->bi_vcnt = vcnt;
1030 * Clone a portion of a bio chain, starting at the given byte offset
1031 * into the first bio in the source chain and continuing for the
1032 * number of bytes indicated. The result is another bio chain of
1033 * exactly the given length, or a null pointer on error.
1035 * The bio_src and offset parameters are both in-out. On entry they
1036 * refer to the first source bio and the offset into that bio where
1037 * the start of data to be cloned is located.
1039 * On return, bio_src is updated to refer to the bio in the source
1040 * chain that contains first un-cloned byte, and *offset will
1041 * contain the offset of that byte within that bio.
1043 static struct bio *bio_chain_clone_range(struct bio **bio_src,
1044 unsigned int *offset,
1048 struct bio *bi = *bio_src;
1049 unsigned int off = *offset;
1050 struct bio *chain = NULL;
1053 /* Build up a chain of clone bios up to the limit */
1055 if (!bi || off >= bi->bi_size || !len)
1056 return NULL; /* Nothing to clone */
1060 unsigned int bi_size;
1064 rbd_warn(NULL, "bio_chain exhausted with %u left", len);
1065 goto out_err; /* EINVAL; ran out of bio's */
1067 bi_size = min_t(unsigned int, bi->bi_size - off, len);
1068 bio = bio_clone_range(bi, off, bi_size, gfpmask);
1070 goto out_err; /* ENOMEM */
1073 end = &bio->bi_next;
1076 if (off == bi->bi_size) {
1087 bio_chain_put(chain);
1093 * The default/initial value for all object request flags is 0. For
1094 * each flag, once its value is set to 1 it is never reset to 0
1097 static void obj_request_img_data_set(struct rbd_obj_request *obj_request)
1099 if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) {
1100 struct rbd_device *rbd_dev;
1102 rbd_dev = obj_request->img_request->rbd_dev;
1103 rbd_warn(rbd_dev, "obj_request %p already marked img_data\n",
1108 static bool obj_request_img_data_test(struct rbd_obj_request *obj_request)
1111 return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0;
1114 static void obj_request_done_set(struct rbd_obj_request *obj_request)
1116 if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) {
1117 struct rbd_device *rbd_dev = NULL;
1119 if (obj_request_img_data_test(obj_request))
1120 rbd_dev = obj_request->img_request->rbd_dev;
1121 rbd_warn(rbd_dev, "obj_request %p already marked done\n",
1126 static bool obj_request_done_test(struct rbd_obj_request *obj_request)
1129 return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0;
1132 static void rbd_obj_request_get(struct rbd_obj_request *obj_request)
1134 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1135 atomic_read(&obj_request->kref.refcount));
1136 kref_get(&obj_request->kref);
1139 static void rbd_obj_request_destroy(struct kref *kref);
1140 static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
1142 rbd_assert(obj_request != NULL);
1143 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1144 atomic_read(&obj_request->kref.refcount));
1145 kref_put(&obj_request->kref, rbd_obj_request_destroy);
1148 static void rbd_img_request_get(struct rbd_img_request *img_request)
1150 dout("%s: img %p (was %d)\n", __func__, img_request,
1151 atomic_read(&img_request->kref.refcount));
1152 kref_get(&img_request->kref);
1155 static void rbd_img_request_destroy(struct kref *kref);
1156 static void rbd_img_request_put(struct rbd_img_request *img_request)
1158 rbd_assert(img_request != NULL);
1159 dout("%s: img %p (was %d)\n", __func__, img_request,
1160 atomic_read(&img_request->kref.refcount));
1161 kref_put(&img_request->kref, rbd_img_request_destroy);
1164 static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
1165 struct rbd_obj_request *obj_request)
1167 rbd_assert(obj_request->img_request == NULL);
1169 /* Image request now owns object's original reference */
1170 obj_request->img_request = img_request;
1171 obj_request->which = img_request->obj_request_count;
1172 rbd_assert(!obj_request_img_data_test(obj_request));
1173 obj_request_img_data_set(obj_request);
1174 rbd_assert(obj_request->which != BAD_WHICH);
1175 img_request->obj_request_count++;
1176 list_add_tail(&obj_request->links, &img_request->obj_requests);
1177 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1178 obj_request->which);
1181 static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
1182 struct rbd_obj_request *obj_request)
1184 rbd_assert(obj_request->which != BAD_WHICH);
1186 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1187 obj_request->which);
1188 list_del(&obj_request->links);
1189 rbd_assert(img_request->obj_request_count > 0);
1190 img_request->obj_request_count--;
1191 rbd_assert(obj_request->which == img_request->obj_request_count);
1192 obj_request->which = BAD_WHICH;
1193 rbd_assert(obj_request_img_data_test(obj_request));
1194 rbd_assert(obj_request->img_request == img_request);
1195 obj_request->img_request = NULL;
1196 obj_request->callback = NULL;
1197 rbd_obj_request_put(obj_request);
1200 static bool obj_request_type_valid(enum obj_request_type type)
1203 case OBJ_REQUEST_NODATA:
1204 case OBJ_REQUEST_BIO:
1205 case OBJ_REQUEST_PAGES:
1212 static int rbd_obj_request_submit(struct ceph_osd_client *osdc,
1213 struct rbd_obj_request *obj_request)
1215 dout("%s: osdc %p obj %p\n", __func__, osdc, obj_request);
1217 return ceph_osdc_start_request(osdc, obj_request->osd_req, false);
1220 static void rbd_img_request_complete(struct rbd_img_request *img_request)
1223 dout("%s: img %p\n", __func__, img_request);
1226 * If no error occurred, compute the aggregate transfer
1227 * count for the image request. We could instead use
1228 * atomic64_cmpxchg() to update it as each object request
1229 * completes; not clear which way is better off hand.
1231 if (!img_request->result) {
1232 struct rbd_obj_request *obj_request;
1235 for_each_obj_request(img_request, obj_request)
1236 xferred += obj_request->xferred;
1237 img_request->xferred = xferred;
1240 if (img_request->callback)
1241 img_request->callback(img_request);
1243 rbd_img_request_put(img_request);
1246 /* Caller is responsible for rbd_obj_request_destroy(obj_request) */
1248 static int rbd_obj_request_wait(struct rbd_obj_request *obj_request)
1250 dout("%s: obj %p\n", __func__, obj_request);
1252 return wait_for_completion_interruptible(&obj_request->completion);
1256 * The default/initial value for all image request flags is 0. Each
1257 * is conditionally set to 1 at image request initialization time
1258 * and currently never change thereafter.
1260 static void img_request_write_set(struct rbd_img_request *img_request)
1262 set_bit(IMG_REQ_WRITE, &img_request->flags);
1266 static bool img_request_write_test(struct rbd_img_request *img_request)
1269 return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0;
1272 static void img_request_child_set(struct rbd_img_request *img_request)
1274 set_bit(IMG_REQ_CHILD, &img_request->flags);
1278 static bool img_request_child_test(struct rbd_img_request *img_request)
1281 return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0;
1284 static void img_request_layered_set(struct rbd_img_request *img_request)
1286 set_bit(IMG_REQ_LAYERED, &img_request->flags);
1290 static bool img_request_layered_test(struct rbd_img_request *img_request)
1293 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
1297 rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
1299 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1300 obj_request, obj_request->img_request, obj_request->result,
1301 obj_request->xferred, obj_request->length);
1303 * ENOENT means a hole in the image. We zero-fill the
1304 * entire length of the request. A short read also implies
1305 * zero-fill to the end of the request. Either way we
1306 * update the xferred count to indicate the whole request
1309 BUG_ON(obj_request->type != OBJ_REQUEST_BIO);
1310 if (obj_request->result == -ENOENT) {
1311 zero_bio_chain(obj_request->bio_list, 0);
1312 obj_request->result = 0;
1313 obj_request->xferred = obj_request->length;
1314 } else if (obj_request->xferred < obj_request->length &&
1315 !obj_request->result) {
1316 zero_bio_chain(obj_request->bio_list, obj_request->xferred);
1317 obj_request->xferred = obj_request->length;
1319 obj_request_done_set(obj_request);
1322 static void rbd_obj_request_complete(struct rbd_obj_request *obj_request)
1324 dout("%s: obj %p cb %p\n", __func__, obj_request,
1325 obj_request->callback);
1326 if (obj_request->callback)
1327 obj_request->callback(obj_request);
1329 complete_all(&obj_request->completion);
1332 static void rbd_osd_trivial_callback(struct rbd_obj_request *obj_request)
1334 dout("%s: obj %p\n", __func__, obj_request);
1335 obj_request_done_set(obj_request);
1338 static void rbd_osd_read_callback(struct rbd_obj_request *obj_request)
1340 struct rbd_img_request *img_request = NULL;
1341 bool layered = false;
1343 if (obj_request_img_data_test(obj_request)) {
1344 img_request = obj_request->img_request;
1345 layered = img_request && img_request_layered_test(img_request);
1351 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1352 obj_request, img_request, obj_request->result,
1353 obj_request->xferred, obj_request->length);
1354 if (layered && obj_request->result == -ENOENT)
1355 rbd_img_parent_read(obj_request);
1356 else if (img_request)
1357 rbd_img_obj_request_read_callback(obj_request);
1359 obj_request_done_set(obj_request);
1362 static void rbd_osd_write_callback(struct rbd_obj_request *obj_request)
1364 dout("%s: obj %p result %d %llu\n", __func__, obj_request,
1365 obj_request->result, obj_request->length);
1367 * There is no such thing as a successful short write. Set
1368 * it to our originally-requested length.
1370 obj_request->xferred = obj_request->length;
1371 obj_request_done_set(obj_request);
1375 * For a simple stat call there's nothing to do. We'll do more if
1376 * this is part of a write sequence for a layered image.
1378 static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request)
1380 dout("%s: obj %p\n", __func__, obj_request);
1381 obj_request_done_set(obj_request);
1384 static void rbd_osd_req_callback(struct ceph_osd_request *osd_req,
1385 struct ceph_msg *msg)
1387 struct rbd_obj_request *obj_request = osd_req->r_priv;
1390 dout("%s: osd_req %p msg %p\n", __func__, osd_req, msg);
1391 rbd_assert(osd_req == obj_request->osd_req);
1392 if (obj_request_img_data_test(obj_request)) {
1393 rbd_assert(obj_request->img_request);
1394 rbd_assert(obj_request->which != BAD_WHICH);
1396 rbd_assert(obj_request->which == BAD_WHICH);
1399 if (osd_req->r_result < 0)
1400 obj_request->result = osd_req->r_result;
1401 obj_request->version = le64_to_cpu(osd_req->r_reassert_version.version);
1403 WARN_ON(osd_req->r_num_ops != 1); /* For now */
1406 * We support a 64-bit length, but ultimately it has to be
1407 * passed to blk_end_request(), which takes an unsigned int.
1409 obj_request->xferred = osd_req->r_reply_op_len[0];
1410 rbd_assert(obj_request->xferred < (u64)UINT_MAX);
1411 opcode = osd_req->r_ops[0].op;
1413 case CEPH_OSD_OP_READ:
1414 rbd_osd_read_callback(obj_request);
1416 case CEPH_OSD_OP_WRITE:
1417 rbd_osd_write_callback(obj_request);
1419 case CEPH_OSD_OP_STAT:
1420 rbd_osd_stat_callback(obj_request);
1422 case CEPH_OSD_OP_CALL:
1423 case CEPH_OSD_OP_NOTIFY_ACK:
1424 case CEPH_OSD_OP_WATCH:
1425 rbd_osd_trivial_callback(obj_request);
1428 rbd_warn(NULL, "%s: unsupported op %hu\n",
1429 obj_request->object_name, (unsigned short) opcode);
1433 if (obj_request_done_test(obj_request))
1434 rbd_obj_request_complete(obj_request);
1437 static void rbd_osd_req_format(struct rbd_obj_request *obj_request,
1440 struct rbd_img_request *img_request = obj_request->img_request;
1441 struct ceph_osd_request *osd_req = obj_request->osd_req;
1442 struct ceph_snap_context *snapc = NULL;
1443 u64 snap_id = CEPH_NOSNAP;
1444 struct timespec *mtime = NULL;
1445 struct timespec now;
1447 rbd_assert(osd_req != NULL);
1449 if (write_request) {
1453 snapc = img_request->snapc;
1454 } else if (img_request) {
1455 snap_id = img_request->snap_id;
1457 ceph_osdc_build_request(osd_req, obj_request->offset,
1458 snapc, snap_id, mtime);
1461 static struct ceph_osd_request *rbd_osd_req_create(
1462 struct rbd_device *rbd_dev,
1464 struct rbd_obj_request *obj_request)
1466 struct ceph_snap_context *snapc = NULL;
1467 struct ceph_osd_client *osdc;
1468 struct ceph_osd_request *osd_req;
1470 if (obj_request_img_data_test(obj_request)) {
1471 struct rbd_img_request *img_request = obj_request->img_request;
1473 rbd_assert(write_request ==
1474 img_request_write_test(img_request));
1476 snapc = img_request->snapc;
1479 /* Allocate and initialize the request, for the single op */
1481 osdc = &rbd_dev->rbd_client->client->osdc;
1482 osd_req = ceph_osdc_alloc_request(osdc, snapc, 1, false, GFP_ATOMIC);
1484 return NULL; /* ENOMEM */
1487 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1489 osd_req->r_flags = CEPH_OSD_FLAG_READ;
1491 osd_req->r_callback = rbd_osd_req_callback;
1492 osd_req->r_priv = obj_request;
1494 osd_req->r_oid_len = strlen(obj_request->object_name);
1495 rbd_assert(osd_req->r_oid_len < sizeof (osd_req->r_oid));
1496 memcpy(osd_req->r_oid, obj_request->object_name, osd_req->r_oid_len);
1498 osd_req->r_file_layout = rbd_dev->layout; /* struct */
1503 static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req)
1505 ceph_osdc_put_request(osd_req);
1508 /* object_name is assumed to be a non-null pointer and NUL-terminated */
1510 static struct rbd_obj_request *rbd_obj_request_create(const char *object_name,
1511 u64 offset, u64 length,
1512 enum obj_request_type type)
1514 struct rbd_obj_request *obj_request;
1518 rbd_assert(obj_request_type_valid(type));
1520 size = strlen(object_name) + 1;
1521 obj_request = kzalloc(sizeof (*obj_request) + size, GFP_KERNEL);
1525 name = (char *)(obj_request + 1);
1526 obj_request->object_name = memcpy(name, object_name, size);
1527 obj_request->offset = offset;
1528 obj_request->length = length;
1529 obj_request->flags = 0;
1530 obj_request->which = BAD_WHICH;
1531 obj_request->type = type;
1532 INIT_LIST_HEAD(&obj_request->links);
1533 init_completion(&obj_request->completion);
1534 kref_init(&obj_request->kref);
1536 dout("%s: \"%s\" %llu/%llu %d -> obj %p\n", __func__, object_name,
1537 offset, length, (int)type, obj_request);
1542 static void rbd_obj_request_destroy(struct kref *kref)
1544 struct rbd_obj_request *obj_request;
1546 obj_request = container_of(kref, struct rbd_obj_request, kref);
1548 dout("%s: obj %p\n", __func__, obj_request);
1550 rbd_assert(obj_request->img_request == NULL);
1551 rbd_assert(obj_request->which == BAD_WHICH);
1553 if (obj_request->osd_req)
1554 rbd_osd_req_destroy(obj_request->osd_req);
1556 rbd_assert(obj_request_type_valid(obj_request->type));
1557 switch (obj_request->type) {
1558 case OBJ_REQUEST_NODATA:
1559 break; /* Nothing to do */
1560 case OBJ_REQUEST_BIO:
1561 if (obj_request->bio_list)
1562 bio_chain_put(obj_request->bio_list);
1564 case OBJ_REQUEST_PAGES:
1565 if (obj_request->pages)
1566 ceph_release_page_vector(obj_request->pages,
1567 obj_request->page_count);
1575 * Caller is responsible for filling in the list of object requests
1576 * that comprises the image request, and the Linux request pointer
1577 * (if there is one).
1579 static struct rbd_img_request *rbd_img_request_create(
1580 struct rbd_device *rbd_dev,
1581 u64 offset, u64 length,
1585 struct rbd_img_request *img_request;
1586 struct ceph_snap_context *snapc = NULL;
1588 img_request = kmalloc(sizeof (*img_request), GFP_ATOMIC);
1592 if (write_request) {
1593 down_read(&rbd_dev->header_rwsem);
1594 snapc = ceph_get_snap_context(rbd_dev->header.snapc);
1595 up_read(&rbd_dev->header_rwsem);
1596 if (WARN_ON(!snapc)) {
1598 return NULL; /* Shouldn't happen */
1603 img_request->rq = NULL;
1604 img_request->rbd_dev = rbd_dev;
1605 img_request->offset = offset;
1606 img_request->length = length;
1607 img_request->flags = 0;
1608 if (write_request) {
1609 img_request_write_set(img_request);
1610 img_request->snapc = snapc;
1612 img_request->snap_id = rbd_dev->spec->snap_id;
1615 img_request_child_set(img_request);
1616 if (rbd_dev->parent_spec)
1617 img_request_layered_set(img_request);
1618 spin_lock_init(&img_request->completion_lock);
1619 img_request->next_completion = 0;
1620 img_request->callback = NULL;
1621 img_request->result = 0;
1622 img_request->obj_request_count = 0;
1623 INIT_LIST_HEAD(&img_request->obj_requests);
1624 kref_init(&img_request->kref);
1626 rbd_img_request_get(img_request); /* Avoid a warning */
1627 rbd_img_request_put(img_request); /* TEMPORARY */
1629 dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev,
1630 write_request ? "write" : "read", offset, length,
1636 static void rbd_img_request_destroy(struct kref *kref)
1638 struct rbd_img_request *img_request;
1639 struct rbd_obj_request *obj_request;
1640 struct rbd_obj_request *next_obj_request;
1642 img_request = container_of(kref, struct rbd_img_request, kref);
1644 dout("%s: img %p\n", __func__, img_request);
1646 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
1647 rbd_img_obj_request_del(img_request, obj_request);
1648 rbd_assert(img_request->obj_request_count == 0);
1650 if (img_request_write_test(img_request))
1651 ceph_put_snap_context(img_request->snapc);
1653 if (img_request_child_test(img_request))
1654 rbd_obj_request_put(img_request->obj_request);
1659 static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request)
1661 struct rbd_img_request *img_request;
1662 unsigned int xferred;
1666 rbd_assert(obj_request_img_data_test(obj_request));
1667 img_request = obj_request->img_request;
1669 rbd_assert(obj_request->xferred <= (u64)UINT_MAX);
1670 xferred = (unsigned int)obj_request->xferred;
1671 result = obj_request->result;
1673 struct rbd_device *rbd_dev = img_request->rbd_dev;
1675 rbd_warn(rbd_dev, "%s %llx at %llx (%llx)\n",
1676 img_request_write_test(img_request) ? "write" : "read",
1677 obj_request->length, obj_request->img_offset,
1678 obj_request->offset);
1679 rbd_warn(rbd_dev, " result %d xferred %x\n",
1681 if (!img_request->result)
1682 img_request->result = result;
1685 if (img_request_child_test(img_request)) {
1686 rbd_assert(img_request->obj_request != NULL);
1687 more = obj_request->which < img_request->obj_request_count - 1;
1689 rbd_assert(img_request->rq != NULL);
1690 more = blk_end_request(img_request->rq, result, xferred);
1696 static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
1698 struct rbd_img_request *img_request;
1699 u32 which = obj_request->which;
1702 rbd_assert(obj_request_img_data_test(obj_request));
1703 img_request = obj_request->img_request;
1705 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
1706 rbd_assert(img_request != NULL);
1707 rbd_assert(img_request->obj_request_count > 0);
1708 rbd_assert(which != BAD_WHICH);
1709 rbd_assert(which < img_request->obj_request_count);
1710 rbd_assert(which >= img_request->next_completion);
1712 spin_lock_irq(&img_request->completion_lock);
1713 if (which != img_request->next_completion)
1716 for_each_obj_request_from(img_request, obj_request) {
1718 rbd_assert(which < img_request->obj_request_count);
1720 if (!obj_request_done_test(obj_request))
1722 more = rbd_img_obj_end_request(obj_request);
1726 rbd_assert(more ^ (which == img_request->obj_request_count));
1727 img_request->next_completion = which;
1729 spin_unlock_irq(&img_request->completion_lock);
1732 rbd_img_request_complete(img_request);
1735 static int rbd_img_request_fill_bio(struct rbd_img_request *img_request,
1736 struct bio *bio_list)
1738 struct rbd_device *rbd_dev = img_request->rbd_dev;
1739 struct rbd_obj_request *obj_request = NULL;
1740 struct rbd_obj_request *next_obj_request;
1741 bool write_request = img_request_write_test(img_request);
1742 unsigned int bio_offset;
1747 dout("%s: img %p bio %p\n", __func__, img_request, bio_list);
1749 opcode = write_request ? CEPH_OSD_OP_WRITE : CEPH_OSD_OP_READ;
1751 img_offset = img_request->offset;
1752 rbd_assert(img_offset == bio_list->bi_sector << SECTOR_SHIFT);
1753 resid = img_request->length;
1754 rbd_assert(resid > 0);
1756 struct ceph_osd_request *osd_req;
1757 const char *object_name;
1758 unsigned int clone_size;
1762 object_name = rbd_segment_name(rbd_dev, img_offset);
1765 offset = rbd_segment_offset(rbd_dev, img_offset);
1766 length = rbd_segment_length(rbd_dev, img_offset, resid);
1767 obj_request = rbd_obj_request_create(object_name,
1770 kfree(object_name); /* object request has its own copy */
1774 rbd_assert(length <= (u64) UINT_MAX);
1775 clone_size = (unsigned int) length;
1776 obj_request->bio_list = bio_chain_clone_range(&bio_list,
1777 &bio_offset, clone_size,
1779 if (!obj_request->bio_list)
1782 osd_req = rbd_osd_req_create(rbd_dev, write_request,
1786 obj_request->osd_req = osd_req;
1787 obj_request->callback = rbd_img_obj_callback;
1789 osd_req_op_extent_init(osd_req, 0, opcode, offset, length,
1791 osd_req_op_extent_osd_data_bio(osd_req, 0,
1792 obj_request->bio_list, obj_request->length);
1793 rbd_osd_req_format(obj_request, write_request);
1795 obj_request->img_offset = img_offset;
1796 rbd_img_obj_request_add(img_request, obj_request);
1798 img_offset += length;
1805 rbd_obj_request_put(obj_request);
1807 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
1808 rbd_obj_request_put(obj_request);
1813 static int rbd_img_request_submit(struct rbd_img_request *img_request)
1815 struct rbd_device *rbd_dev = img_request->rbd_dev;
1816 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1817 struct rbd_obj_request *obj_request;
1818 struct rbd_obj_request *next_obj_request;
1820 dout("%s: img %p\n", __func__, img_request);
1821 for_each_obj_request_safe(img_request, obj_request, next_obj_request) {
1824 ret = rbd_obj_request_submit(osdc, obj_request);
1832 static void rbd_img_parent_read_callback(struct rbd_img_request *img_request)
1834 struct rbd_obj_request *obj_request;
1836 rbd_assert(img_request_child_test(img_request));
1838 obj_request = img_request->obj_request;
1839 rbd_assert(obj_request != NULL);
1840 obj_request->result = img_request->result;
1841 obj_request->xferred = img_request->xferred;
1843 rbd_img_obj_request_read_callback(obj_request);
1844 rbd_obj_request_complete(obj_request);
1847 static void rbd_img_parent_read(struct rbd_obj_request *obj_request)
1849 struct rbd_device *rbd_dev;
1850 struct rbd_img_request *img_request;
1853 rbd_assert(obj_request_img_data_test(obj_request));
1854 rbd_assert(obj_request->img_request != NULL);
1855 rbd_assert(obj_request->result == (s32) -ENOENT);
1856 rbd_assert(obj_request->type == OBJ_REQUEST_BIO);
1858 rbd_dev = obj_request->img_request->rbd_dev;
1859 rbd_assert(rbd_dev->parent != NULL);
1860 /* rbd_read_finish(obj_request, obj_request->length); */
1861 img_request = rbd_img_request_create(rbd_dev->parent,
1862 obj_request->img_offset,
1863 obj_request->length,
1869 rbd_obj_request_get(obj_request);
1870 img_request->obj_request = obj_request;
1872 result = rbd_img_request_fill_bio(img_request, obj_request->bio_list);
1876 img_request->callback = rbd_img_parent_read_callback;
1877 result = rbd_img_request_submit(img_request);
1884 rbd_img_request_put(img_request);
1885 obj_request->result = result;
1886 obj_request->xferred = 0;
1887 obj_request_done_set(obj_request);
1890 static int rbd_obj_notify_ack(struct rbd_device *rbd_dev,
1891 u64 ver, u64 notify_id)
1893 struct rbd_obj_request *obj_request;
1894 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1897 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
1898 OBJ_REQUEST_NODATA);
1903 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
1904 if (!obj_request->osd_req)
1906 obj_request->callback = rbd_obj_request_put;
1908 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK,
1910 rbd_osd_req_format(obj_request, false);
1912 ret = rbd_obj_request_submit(osdc, obj_request);
1915 rbd_obj_request_put(obj_request);
1920 static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
1922 struct rbd_device *rbd_dev = (struct rbd_device *)data;
1929 dout("%s: \"%s\" notify_id %llu opcode %u\n", __func__,
1930 rbd_dev->header_name, (unsigned long long) notify_id,
1931 (unsigned int) opcode);
1932 rc = rbd_dev_refresh(rbd_dev, &hver);
1934 rbd_warn(rbd_dev, "got notification but failed to "
1935 " update snaps: %d\n", rc);
1937 rbd_obj_notify_ack(rbd_dev, hver, notify_id);
1941 * Request sync osd watch/unwatch. The value of "start" determines
1942 * whether a watch request is being initiated or torn down.
1944 static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, int start)
1946 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1947 struct rbd_obj_request *obj_request;
1950 rbd_assert(start ^ !!rbd_dev->watch_event);
1951 rbd_assert(start ^ !!rbd_dev->watch_request);
1954 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
1955 &rbd_dev->watch_event);
1958 rbd_assert(rbd_dev->watch_event != NULL);
1962 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
1963 OBJ_REQUEST_NODATA);
1967 obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, obj_request);
1968 if (!obj_request->osd_req)
1972 ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
1974 ceph_osdc_unregister_linger_request(osdc,
1975 rbd_dev->watch_request->osd_req);
1977 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
1978 rbd_dev->watch_event->cookie,
1979 rbd_dev->header.obj_version, start);
1980 rbd_osd_req_format(obj_request, true);
1982 ret = rbd_obj_request_submit(osdc, obj_request);
1985 ret = rbd_obj_request_wait(obj_request);
1988 ret = obj_request->result;
1993 * A watch request is set to linger, so the underlying osd
1994 * request won't go away until we unregister it. We retain
1995 * a pointer to the object request during that time (in
1996 * rbd_dev->watch_request), so we'll keep a reference to
1997 * it. We'll drop that reference (below) after we've
2001 rbd_dev->watch_request = obj_request;
2006 /* We have successfully torn down the watch request */
2008 rbd_obj_request_put(rbd_dev->watch_request);
2009 rbd_dev->watch_request = NULL;
2011 /* Cancel the event if we're tearing down, or on error */
2012 ceph_osdc_cancel_event(rbd_dev->watch_event);
2013 rbd_dev->watch_event = NULL;
2015 rbd_obj_request_put(obj_request);
2021 * Synchronous osd object method call
2023 static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
2024 const char *object_name,
2025 const char *class_name,
2026 const char *method_name,
2027 const char *outbound,
2028 size_t outbound_size,
2030 size_t inbound_size,
2033 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2034 struct rbd_obj_request *obj_request;
2035 struct page **pages;
2040 * Method calls are ultimately read operations. The result
2041 * should placed into the inbound buffer provided. They
2042 * also supply outbound data--parameters for the object
2043 * method. Currently if this is present it will be a
2046 page_count = (u32) calc_pages_for(0, inbound_size);
2047 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2049 return PTR_ERR(pages);
2052 obj_request = rbd_obj_request_create(object_name, 0, inbound_size,
2057 obj_request->pages = pages;
2058 obj_request->page_count = page_count;
2060 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
2061 if (!obj_request->osd_req)
2064 osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL,
2065 class_name, method_name);
2066 if (outbound_size) {
2067 struct ceph_pagelist *pagelist;
2069 pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS);
2073 ceph_pagelist_init(pagelist);
2074 ceph_pagelist_append(pagelist, outbound, outbound_size);
2075 osd_req_op_cls_request_data_pagelist(obj_request->osd_req, 0,
2078 osd_req_op_cls_response_data_pages(obj_request->osd_req, 0,
2079 obj_request->pages, inbound_size,
2081 rbd_osd_req_format(obj_request, false);
2083 ret = rbd_obj_request_submit(osdc, obj_request);
2086 ret = rbd_obj_request_wait(obj_request);
2090 ret = obj_request->result;
2094 ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred);
2096 *version = obj_request->version;
2099 rbd_obj_request_put(obj_request);
2101 ceph_release_page_vector(pages, page_count);
2106 static void rbd_request_fn(struct request_queue *q)
2107 __releases(q->queue_lock) __acquires(q->queue_lock)
2109 struct rbd_device *rbd_dev = q->queuedata;
2110 bool read_only = rbd_dev->mapping.read_only;
2114 while ((rq = blk_fetch_request(q))) {
2115 bool write_request = rq_data_dir(rq) == WRITE;
2116 struct rbd_img_request *img_request;
2120 /* Ignore any non-FS requests that filter through. */
2122 if (rq->cmd_type != REQ_TYPE_FS) {
2123 dout("%s: non-fs request type %d\n", __func__,
2124 (int) rq->cmd_type);
2125 __blk_end_request_all(rq, 0);
2129 /* Ignore/skip any zero-length requests */
2131 offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT;
2132 length = (u64) blk_rq_bytes(rq);
2135 dout("%s: zero-length request\n", __func__);
2136 __blk_end_request_all(rq, 0);
2140 spin_unlock_irq(q->queue_lock);
2142 /* Disallow writes to a read-only device */
2144 if (write_request) {
2148 rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP);
2152 * Quit early if the mapped snapshot no longer
2153 * exists. It's still possible the snapshot will
2154 * have disappeared by the time our request arrives
2155 * at the osd, but there's no sense in sending it if
2158 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) {
2159 dout("request for non-existent snapshot");
2160 rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP);
2166 if (WARN_ON(offset && length > U64_MAX - offset + 1))
2167 goto end_request; /* Shouldn't happen */
2170 img_request = rbd_img_request_create(rbd_dev, offset, length,
2171 write_request, false);
2175 img_request->rq = rq;
2177 result = rbd_img_request_fill_bio(img_request, rq->bio);
2179 result = rbd_img_request_submit(img_request);
2181 rbd_img_request_put(img_request);
2183 spin_lock_irq(q->queue_lock);
2185 rbd_warn(rbd_dev, "%s %llx at %llx result %d\n",
2186 write_request ? "write" : "read",
2187 length, offset, result);
2189 __blk_end_request_all(rq, result);
2195 * a queue callback. Makes sure that we don't create a bio that spans across
2196 * multiple osd objects. One exception would be with a single page bios,
2197 * which we handle later at bio_chain_clone_range()
2199 static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2200 struct bio_vec *bvec)
2202 struct rbd_device *rbd_dev = q->queuedata;
2203 sector_t sector_offset;
2204 sector_t sectors_per_obj;
2205 sector_t obj_sector_offset;
2209 * Find how far into its rbd object the partition-relative
2210 * bio start sector is to offset relative to the enclosing
2213 sector_offset = get_start_sect(bmd->bi_bdev) + bmd->bi_sector;
2214 sectors_per_obj = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT);
2215 obj_sector_offset = sector_offset & (sectors_per_obj - 1);
2218 * Compute the number of bytes from that offset to the end
2219 * of the object. Account for what's already used by the bio.
2221 ret = (int) (sectors_per_obj - obj_sector_offset) << SECTOR_SHIFT;
2222 if (ret > bmd->bi_size)
2223 ret -= bmd->bi_size;
2228 * Don't send back more than was asked for. And if the bio
2229 * was empty, let the whole thing through because: "Note
2230 * that a block device *must* allow a single page to be
2231 * added to an empty bio."
2233 rbd_assert(bvec->bv_len <= PAGE_SIZE);
2234 if (ret > (int) bvec->bv_len || !bmd->bi_size)
2235 ret = (int) bvec->bv_len;
2240 static void rbd_free_disk(struct rbd_device *rbd_dev)
2242 struct gendisk *disk = rbd_dev->disk;
2247 if (disk->flags & GENHD_FL_UP)
2250 blk_cleanup_queue(disk->queue);
2254 static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
2255 const char *object_name,
2256 u64 offset, u64 length,
2257 char *buf, u64 *version)
2260 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2261 struct rbd_obj_request *obj_request;
2262 struct page **pages = NULL;
2267 page_count = (u32) calc_pages_for(offset, length);
2268 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2270 ret = PTR_ERR(pages);
2273 obj_request = rbd_obj_request_create(object_name, offset, length,
2278 obj_request->pages = pages;
2279 obj_request->page_count = page_count;
2281 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
2282 if (!obj_request->osd_req)
2285 osd_req_op_extent_init(obj_request->osd_req, 0, CEPH_OSD_OP_READ,
2286 offset, length, 0, 0);
2287 osd_req_op_extent_osd_data_pages(obj_request->osd_req, 0,
2289 obj_request->length,
2290 obj_request->offset & ~PAGE_MASK,
2292 rbd_osd_req_format(obj_request, false);
2294 ret = rbd_obj_request_submit(osdc, obj_request);
2297 ret = rbd_obj_request_wait(obj_request);
2301 ret = obj_request->result;
2305 rbd_assert(obj_request->xferred <= (u64) SIZE_MAX);
2306 size = (size_t) obj_request->xferred;
2307 ceph_copy_from_page_vector(pages, buf, 0, size);
2308 rbd_assert(size <= (size_t) INT_MAX);
2311 *version = obj_request->version;
2314 rbd_obj_request_put(obj_request);
2316 ceph_release_page_vector(pages, page_count);
2322 * Read the complete header for the given rbd device.
2324 * Returns a pointer to a dynamically-allocated buffer containing
2325 * the complete and validated header. Caller can pass the address
2326 * of a variable that will be filled in with the version of the
2327 * header object at the time it was read.
2329 * Returns a pointer-coded errno if a failure occurs.
2331 static struct rbd_image_header_ondisk *
2332 rbd_dev_v1_header_read(struct rbd_device *rbd_dev, u64 *version)
2334 struct rbd_image_header_ondisk *ondisk = NULL;
2341 * The complete header will include an array of its 64-bit
2342 * snapshot ids, followed by the names of those snapshots as
2343 * a contiguous block of NUL-terminated strings. Note that
2344 * the number of snapshots could change by the time we read
2345 * it in, in which case we re-read it.
2352 size = sizeof (*ondisk);
2353 size += snap_count * sizeof (struct rbd_image_snap_ondisk);
2355 ondisk = kmalloc(size, GFP_KERNEL);
2357 return ERR_PTR(-ENOMEM);
2359 ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name,
2361 (char *) ondisk, version);
2364 if (WARN_ON((size_t) ret < size)) {
2366 rbd_warn(rbd_dev, "short header read (want %zd got %d)",
2370 if (!rbd_dev_ondisk_valid(ondisk)) {
2372 rbd_warn(rbd_dev, "invalid header");
2376 names_size = le64_to_cpu(ondisk->snap_names_len);
2377 want_count = snap_count;
2378 snap_count = le32_to_cpu(ondisk->snap_count);
2379 } while (snap_count != want_count);
2386 return ERR_PTR(ret);
2390 * reload the ondisk the header
2392 static int rbd_read_header(struct rbd_device *rbd_dev,
2393 struct rbd_image_header *header)
2395 struct rbd_image_header_ondisk *ondisk;
2399 ondisk = rbd_dev_v1_header_read(rbd_dev, &ver);
2401 return PTR_ERR(ondisk);
2402 ret = rbd_header_from_disk(header, ondisk);
2404 header->obj_version = ver;
2410 static void rbd_remove_all_snaps(struct rbd_device *rbd_dev)
2412 struct rbd_snap *snap;
2413 struct rbd_snap *next;
2415 list_for_each_entry_safe(snap, next, &rbd_dev->snaps, node)
2416 rbd_remove_snap_dev(snap);
2419 static void rbd_update_mapping_size(struct rbd_device *rbd_dev)
2423 if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
2426 size = (sector_t) rbd_dev->header.image_size / SECTOR_SIZE;
2427 dout("setting size to %llu sectors", (unsigned long long) size);
2428 rbd_dev->mapping.size = (u64) size;
2429 set_capacity(rbd_dev->disk, size);
2433 * only read the first part of the ondisk header, without the snaps info
2435 static int rbd_dev_v1_refresh(struct rbd_device *rbd_dev, u64 *hver)
2438 struct rbd_image_header h;
2440 ret = rbd_read_header(rbd_dev, &h);
2444 down_write(&rbd_dev->header_rwsem);
2446 /* Update image size, and check for resize of mapped image */
2447 rbd_dev->header.image_size = h.image_size;
2448 rbd_update_mapping_size(rbd_dev);
2450 /* rbd_dev->header.object_prefix shouldn't change */
2451 kfree(rbd_dev->header.snap_sizes);
2452 kfree(rbd_dev->header.snap_names);
2453 /* osd requests may still refer to snapc */
2454 ceph_put_snap_context(rbd_dev->header.snapc);
2457 *hver = h.obj_version;
2458 rbd_dev->header.obj_version = h.obj_version;
2459 rbd_dev->header.image_size = h.image_size;
2460 rbd_dev->header.snapc = h.snapc;
2461 rbd_dev->header.snap_names = h.snap_names;
2462 rbd_dev->header.snap_sizes = h.snap_sizes;
2463 /* Free the extra copy of the object prefix */
2464 WARN_ON(strcmp(rbd_dev->header.object_prefix, h.object_prefix));
2465 kfree(h.object_prefix);
2467 ret = rbd_dev_snaps_update(rbd_dev);
2469 ret = rbd_dev_snaps_register(rbd_dev);
2471 up_write(&rbd_dev->header_rwsem);
2476 static int rbd_dev_refresh(struct rbd_device *rbd_dev, u64 *hver)
2480 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
2481 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2482 if (rbd_dev->image_format == 1)
2483 ret = rbd_dev_v1_refresh(rbd_dev, hver);
2485 ret = rbd_dev_v2_refresh(rbd_dev, hver);
2486 mutex_unlock(&ctl_mutex);
2491 static int rbd_init_disk(struct rbd_device *rbd_dev)
2493 struct gendisk *disk;
2494 struct request_queue *q;
2497 /* create gendisk info */
2498 disk = alloc_disk(RBD_MINORS_PER_MAJOR);
2502 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
2504 disk->major = rbd_dev->major;
2505 disk->first_minor = 0;
2506 disk->fops = &rbd_bd_ops;
2507 disk->private_data = rbd_dev;
2509 q = blk_init_queue(rbd_request_fn, &rbd_dev->lock);
2513 /* We use the default size, but let's be explicit about it. */
2514 blk_queue_physical_block_size(q, SECTOR_SIZE);
2516 /* set io sizes to object size */
2517 segment_size = rbd_obj_bytes(&rbd_dev->header);
2518 blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
2519 blk_queue_max_segment_size(q, segment_size);
2520 blk_queue_io_min(q, segment_size);
2521 blk_queue_io_opt(q, segment_size);
2523 blk_queue_merge_bvec(q, rbd_merge_bvec);
2526 q->queuedata = rbd_dev;
2528 rbd_dev->disk = disk;
2530 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
2543 static struct rbd_device *dev_to_rbd_dev(struct device *dev)
2545 return container_of(dev, struct rbd_device, dev);
2548 static ssize_t rbd_size_show(struct device *dev,
2549 struct device_attribute *attr, char *buf)
2551 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2554 down_read(&rbd_dev->header_rwsem);
2555 size = get_capacity(rbd_dev->disk);
2556 up_read(&rbd_dev->header_rwsem);
2558 return sprintf(buf, "%llu\n", (unsigned long long) size * SECTOR_SIZE);
2562 * Note this shows the features for whatever's mapped, which is not
2563 * necessarily the base image.
2565 static ssize_t rbd_features_show(struct device *dev,
2566 struct device_attribute *attr, char *buf)
2568 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2570 return sprintf(buf, "0x%016llx\n",
2571 (unsigned long long) rbd_dev->mapping.features);
2574 static ssize_t rbd_major_show(struct device *dev,
2575 struct device_attribute *attr, char *buf)
2577 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2579 return sprintf(buf, "%d\n", rbd_dev->major);
2582 static ssize_t rbd_client_id_show(struct device *dev,
2583 struct device_attribute *attr, char *buf)
2585 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2587 return sprintf(buf, "client%lld\n",
2588 ceph_client_id(rbd_dev->rbd_client->client));
2591 static ssize_t rbd_pool_show(struct device *dev,
2592 struct device_attribute *attr, char *buf)
2594 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2596 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
2599 static ssize_t rbd_pool_id_show(struct device *dev,
2600 struct device_attribute *attr, char *buf)
2602 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2604 return sprintf(buf, "%llu\n",
2605 (unsigned long long) rbd_dev->spec->pool_id);
2608 static ssize_t rbd_name_show(struct device *dev,
2609 struct device_attribute *attr, char *buf)
2611 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2613 if (rbd_dev->spec->image_name)
2614 return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
2616 return sprintf(buf, "(unknown)\n");
2619 static ssize_t rbd_image_id_show(struct device *dev,
2620 struct device_attribute *attr, char *buf)
2622 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2624 return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
2628 * Shows the name of the currently-mapped snapshot (or
2629 * RBD_SNAP_HEAD_NAME for the base image).
2631 static ssize_t rbd_snap_show(struct device *dev,
2632 struct device_attribute *attr,
2635 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2637 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
2641 * For an rbd v2 image, shows the pool id, image id, and snapshot id
2642 * for the parent image. If there is no parent, simply shows
2643 * "(no parent image)".
2645 static ssize_t rbd_parent_show(struct device *dev,
2646 struct device_attribute *attr,
2649 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2650 struct rbd_spec *spec = rbd_dev->parent_spec;
2655 return sprintf(buf, "(no parent image)\n");
2657 count = sprintf(bufp, "pool_id %llu\npool_name %s\n",
2658 (unsigned long long) spec->pool_id, spec->pool_name);
2663 count = sprintf(bufp, "image_id %s\nimage_name %s\n", spec->image_id,
2664 spec->image_name ? spec->image_name : "(unknown)");
2669 count = sprintf(bufp, "snap_id %llu\nsnap_name %s\n",
2670 (unsigned long long) spec->snap_id, spec->snap_name);
2675 count = sprintf(bufp, "overlap %llu\n", rbd_dev->parent_overlap);
2680 return (ssize_t) (bufp - buf);
2683 static ssize_t rbd_image_refresh(struct device *dev,
2684 struct device_attribute *attr,
2688 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2691 ret = rbd_dev_refresh(rbd_dev, NULL);
2693 return ret < 0 ? ret : size;
2696 static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
2697 static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL);
2698 static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
2699 static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
2700 static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
2701 static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL);
2702 static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
2703 static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL);
2704 static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
2705 static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
2706 static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL);
2708 static struct attribute *rbd_attrs[] = {
2709 &dev_attr_size.attr,
2710 &dev_attr_features.attr,
2711 &dev_attr_major.attr,
2712 &dev_attr_client_id.attr,
2713 &dev_attr_pool.attr,
2714 &dev_attr_pool_id.attr,
2715 &dev_attr_name.attr,
2716 &dev_attr_image_id.attr,
2717 &dev_attr_current_snap.attr,
2718 &dev_attr_parent.attr,
2719 &dev_attr_refresh.attr,
2723 static struct attribute_group rbd_attr_group = {
2727 static const struct attribute_group *rbd_attr_groups[] = {
2732 static void rbd_sysfs_dev_release(struct device *dev)
2736 static struct device_type rbd_device_type = {
2738 .groups = rbd_attr_groups,
2739 .release = rbd_sysfs_dev_release,
2747 static ssize_t rbd_snap_size_show(struct device *dev,
2748 struct device_attribute *attr,
2751 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
2753 return sprintf(buf, "%llu\n", (unsigned long long)snap->size);
2756 static ssize_t rbd_snap_id_show(struct device *dev,
2757 struct device_attribute *attr,
2760 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
2762 return sprintf(buf, "%llu\n", (unsigned long long)snap->id);
2765 static ssize_t rbd_snap_features_show(struct device *dev,
2766 struct device_attribute *attr,
2769 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
2771 return sprintf(buf, "0x%016llx\n",
2772 (unsigned long long) snap->features);
2775 static DEVICE_ATTR(snap_size, S_IRUGO, rbd_snap_size_show, NULL);
2776 static DEVICE_ATTR(snap_id, S_IRUGO, rbd_snap_id_show, NULL);
2777 static DEVICE_ATTR(snap_features, S_IRUGO, rbd_snap_features_show, NULL);
2779 static struct attribute *rbd_snap_attrs[] = {
2780 &dev_attr_snap_size.attr,
2781 &dev_attr_snap_id.attr,
2782 &dev_attr_snap_features.attr,
2786 static struct attribute_group rbd_snap_attr_group = {
2787 .attrs = rbd_snap_attrs,
2790 static void rbd_snap_dev_release(struct device *dev)
2792 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
2797 static const struct attribute_group *rbd_snap_attr_groups[] = {
2798 &rbd_snap_attr_group,
2802 static struct device_type rbd_snap_device_type = {
2803 .groups = rbd_snap_attr_groups,
2804 .release = rbd_snap_dev_release,
2807 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
2809 kref_get(&spec->kref);
2814 static void rbd_spec_free(struct kref *kref);
2815 static void rbd_spec_put(struct rbd_spec *spec)
2818 kref_put(&spec->kref, rbd_spec_free);
2821 static struct rbd_spec *rbd_spec_alloc(void)
2823 struct rbd_spec *spec;
2825 spec = kzalloc(sizeof (*spec), GFP_KERNEL);
2828 kref_init(&spec->kref);
2833 static void rbd_spec_free(struct kref *kref)
2835 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
2837 kfree(spec->pool_name);
2838 kfree(spec->image_id);
2839 kfree(spec->image_name);
2840 kfree(spec->snap_name);
2844 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
2845 struct rbd_spec *spec)
2847 struct rbd_device *rbd_dev;
2849 rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL);
2853 spin_lock_init(&rbd_dev->lock);
2855 INIT_LIST_HEAD(&rbd_dev->node);
2856 INIT_LIST_HEAD(&rbd_dev->snaps);
2857 init_rwsem(&rbd_dev->header_rwsem);
2859 rbd_dev->spec = spec;
2860 rbd_dev->rbd_client = rbdc;
2862 /* Initialize the layout used for all rbd requests */
2864 rbd_dev->layout.fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
2865 rbd_dev->layout.fl_stripe_count = cpu_to_le32(1);
2866 rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
2867 rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id);
2872 static void rbd_dev_destroy(struct rbd_device *rbd_dev)
2874 rbd_spec_put(rbd_dev->parent_spec);
2875 kfree(rbd_dev->header_name);
2876 rbd_put_client(rbd_dev->rbd_client);
2877 rbd_spec_put(rbd_dev->spec);
2881 static bool rbd_snap_registered(struct rbd_snap *snap)
2883 bool ret = snap->dev.type == &rbd_snap_device_type;
2884 bool reg = device_is_registered(&snap->dev);
2886 rbd_assert(!ret ^ reg);
2891 static void rbd_remove_snap_dev(struct rbd_snap *snap)
2893 list_del(&snap->node);
2894 if (device_is_registered(&snap->dev))
2895 device_unregister(&snap->dev);
2898 static int rbd_register_snap_dev(struct rbd_snap *snap,
2899 struct device *parent)
2901 struct device *dev = &snap->dev;
2904 dev->type = &rbd_snap_device_type;
2905 dev->parent = parent;
2906 dev->release = rbd_snap_dev_release;
2907 dev_set_name(dev, "%s%s", RBD_SNAP_DEV_NAME_PREFIX, snap->name);
2908 dout("%s: registering device for snapshot %s\n", __func__, snap->name);
2910 ret = device_register(dev);
2915 static struct rbd_snap *__rbd_add_snap_dev(struct rbd_device *rbd_dev,
2916 const char *snap_name,
2917 u64 snap_id, u64 snap_size,
2920 struct rbd_snap *snap;
2923 snap = kzalloc(sizeof (*snap), GFP_KERNEL);
2925 return ERR_PTR(-ENOMEM);
2928 snap->name = kstrdup(snap_name, GFP_KERNEL);
2933 snap->size = snap_size;
2934 snap->features = snap_features;
2942 return ERR_PTR(ret);
2945 static char *rbd_dev_v1_snap_info(struct rbd_device *rbd_dev, u32 which,
2946 u64 *snap_size, u64 *snap_features)
2950 rbd_assert(which < rbd_dev->header.snapc->num_snaps);
2952 *snap_size = rbd_dev->header.snap_sizes[which];
2953 *snap_features = 0; /* No features for v1 */
2955 /* Skip over names until we find the one we are looking for */
2957 snap_name = rbd_dev->header.snap_names;
2959 snap_name += strlen(snap_name) + 1;
2965 * Get the size and object order for an image snapshot, or if
2966 * snap_id is CEPH_NOSNAP, gets this information for the base
2969 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
2970 u8 *order, u64 *snap_size)
2972 __le64 snapid = cpu_to_le64(snap_id);
2977 } __attribute__ ((packed)) size_buf = { 0 };
2979 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
2981 (char *) &snapid, sizeof (snapid),
2982 (char *) &size_buf, sizeof (size_buf), NULL);
2983 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
2987 *order = size_buf.order;
2988 *snap_size = le64_to_cpu(size_buf.size);
2990 dout(" snap_id 0x%016llx order = %u, snap_size = %llu\n",
2991 (unsigned long long) snap_id, (unsigned int) *order,
2992 (unsigned long long) *snap_size);
2997 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
2999 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
3000 &rbd_dev->header.obj_order,
3001 &rbd_dev->header.image_size);
3004 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
3010 reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL);
3014 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3015 "rbd", "get_object_prefix",
3017 reply_buf, RBD_OBJ_PREFIX_LEN_MAX, NULL);
3018 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3023 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
3024 p + RBD_OBJ_PREFIX_LEN_MAX,
3027 if (IS_ERR(rbd_dev->header.object_prefix)) {
3028 ret = PTR_ERR(rbd_dev->header.object_prefix);
3029 rbd_dev->header.object_prefix = NULL;
3031 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix);
3040 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
3043 __le64 snapid = cpu_to_le64(snap_id);
3047 } features_buf = { 0 };
3051 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3052 "rbd", "get_features",
3053 (char *) &snapid, sizeof (snapid),
3054 (char *) &features_buf, sizeof (features_buf),
3056 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3060 incompat = le64_to_cpu(features_buf.incompat);
3061 if (incompat & ~RBD_FEATURES_SUPPORTED)
3064 *snap_features = le64_to_cpu(features_buf.features);
3066 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
3067 (unsigned long long) snap_id,
3068 (unsigned long long) *snap_features,
3069 (unsigned long long) le64_to_cpu(features_buf.incompat));
3074 static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
3076 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
3077 &rbd_dev->header.features);
3080 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
3082 struct rbd_spec *parent_spec;
3084 void *reply_buf = NULL;
3092 parent_spec = rbd_spec_alloc();
3096 size = sizeof (__le64) + /* pool_id */
3097 sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */
3098 sizeof (__le64) + /* snap_id */
3099 sizeof (__le64); /* overlap */
3100 reply_buf = kmalloc(size, GFP_KERNEL);
3106 snapid = cpu_to_le64(CEPH_NOSNAP);
3107 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3108 "rbd", "get_parent",
3109 (char *) &snapid, sizeof (snapid),
3110 (char *) reply_buf, size, NULL);
3111 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3117 end = (char *) reply_buf + size;
3118 ceph_decode_64_safe(&p, end, parent_spec->pool_id, out_err);
3119 if (parent_spec->pool_id == CEPH_NOPOOL)
3120 goto out; /* No parent? No problem. */
3122 /* The ceph file layout needs to fit pool id in 32 bits */
3125 if (WARN_ON(parent_spec->pool_id > (u64) U32_MAX))
3128 image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
3129 if (IS_ERR(image_id)) {
3130 ret = PTR_ERR(image_id);
3133 parent_spec->image_id = image_id;
3134 ceph_decode_64_safe(&p, end, parent_spec->snap_id, out_err);
3135 ceph_decode_64_safe(&p, end, overlap, out_err);
3137 rbd_dev->parent_overlap = overlap;
3138 rbd_dev->parent_spec = parent_spec;
3139 parent_spec = NULL; /* rbd_dev now owns this */
3144 rbd_spec_put(parent_spec);
3149 static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
3151 size_t image_id_size;
3156 void *reply_buf = NULL;
3158 char *image_name = NULL;
3161 rbd_assert(!rbd_dev->spec->image_name);
3163 len = strlen(rbd_dev->spec->image_id);
3164 image_id_size = sizeof (__le32) + len;
3165 image_id = kmalloc(image_id_size, GFP_KERNEL);
3170 end = (char *) image_id + image_id_size;
3171 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32) len);
3173 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
3174 reply_buf = kmalloc(size, GFP_KERNEL);
3178 ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY,
3179 "rbd", "dir_get_name",
3180 image_id, image_id_size,
3181 (char *) reply_buf, size, NULL);
3185 end = (char *) reply_buf + size;
3186 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
3187 if (IS_ERR(image_name))
3190 dout("%s: name is %s len is %zd\n", __func__, image_name, len);
3199 * When a parent image gets probed, we only have the pool, image,
3200 * and snapshot ids but not the names of any of them. This call
3201 * is made later to fill in those names. It has to be done after
3202 * rbd_dev_snaps_update() has completed because some of the
3203 * information (in particular, snapshot name) is not available
3206 static int rbd_dev_probe_update_spec(struct rbd_device *rbd_dev)
3208 struct ceph_osd_client *osdc;
3210 void *reply_buf = NULL;
3213 if (rbd_dev->spec->pool_name)
3214 return 0; /* Already have the names */
3216 /* Look up the pool name */
3218 osdc = &rbd_dev->rbd_client->client->osdc;
3219 name = ceph_pg_pool_name_by_id(osdc->osdmap, rbd_dev->spec->pool_id);
3221 rbd_warn(rbd_dev, "there is no pool with id %llu",
3222 rbd_dev->spec->pool_id); /* Really a BUG() */
3226 rbd_dev->spec->pool_name = kstrdup(name, GFP_KERNEL);
3227 if (!rbd_dev->spec->pool_name)
3230 /* Fetch the image name; tolerate failure here */
3232 name = rbd_dev_image_name(rbd_dev);
3234 rbd_dev->spec->image_name = (char *) name;
3236 rbd_warn(rbd_dev, "unable to get image name");
3238 /* Look up the snapshot name. */
3240 name = rbd_snap_name(rbd_dev, rbd_dev->spec->snap_id);
3242 rbd_warn(rbd_dev, "no snapshot with id %llu",
3243 rbd_dev->spec->snap_id); /* Really a BUG() */
3247 rbd_dev->spec->snap_name = kstrdup(name, GFP_KERNEL);
3248 if(!rbd_dev->spec->snap_name)
3254 kfree(rbd_dev->spec->pool_name);
3255 rbd_dev->spec->pool_name = NULL;
3260 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev, u64 *ver)
3269 struct ceph_snap_context *snapc;
3273 * We'll need room for the seq value (maximum snapshot id),
3274 * snapshot count, and array of that many snapshot ids.
3275 * For now we have a fixed upper limit on the number we're
3276 * prepared to receive.
3278 size = sizeof (__le64) + sizeof (__le32) +
3279 RBD_MAX_SNAP_COUNT * sizeof (__le64);
3280 reply_buf = kzalloc(size, GFP_KERNEL);
3284 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3285 "rbd", "get_snapcontext",
3287 reply_buf, size, ver);
3288 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3294 end = (char *) reply_buf + size;
3295 ceph_decode_64_safe(&p, end, seq, out);
3296 ceph_decode_32_safe(&p, end, snap_count, out);
3299 * Make sure the reported number of snapshot ids wouldn't go
3300 * beyond the end of our buffer. But before checking that,
3301 * make sure the computed size of the snapshot context we
3302 * allocate is representable in a size_t.
3304 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
3309 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
3312 size = sizeof (struct ceph_snap_context) +
3313 snap_count * sizeof (snapc->snaps[0]);
3314 snapc = kmalloc(size, GFP_KERNEL);
3320 atomic_set(&snapc->nref, 1);
3322 snapc->num_snaps = snap_count;
3323 for (i = 0; i < snap_count; i++)
3324 snapc->snaps[i] = ceph_decode_64(&p);
3326 rbd_dev->header.snapc = snapc;
3328 dout(" snap context seq = %llu, snap_count = %u\n",
3329 (unsigned long long) seq, (unsigned int) snap_count);
3337 static char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, u32 which)
3347 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
3348 reply_buf = kmalloc(size, GFP_KERNEL);
3350 return ERR_PTR(-ENOMEM);
3352 snap_id = cpu_to_le64(rbd_dev->header.snapc->snaps[which]);
3353 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3354 "rbd", "get_snapshot_name",
3355 (char *) &snap_id, sizeof (snap_id),
3356 reply_buf, size, NULL);
3357 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3362 end = (char *) reply_buf + size;
3363 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
3364 if (IS_ERR(snap_name)) {
3365 ret = PTR_ERR(snap_name);
3368 dout(" snap_id 0x%016llx snap_name = %s\n",
3369 (unsigned long long) le64_to_cpu(snap_id), snap_name);
3377 return ERR_PTR(ret);
3380 static char *rbd_dev_v2_snap_info(struct rbd_device *rbd_dev, u32 which,
3381 u64 *snap_size, u64 *snap_features)
3387 snap_id = rbd_dev->header.snapc->snaps[which];
3388 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, &order, snap_size);
3390 return ERR_PTR(ret);
3391 ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, snap_features);
3393 return ERR_PTR(ret);
3395 return rbd_dev_v2_snap_name(rbd_dev, which);
3398 static char *rbd_dev_snap_info(struct rbd_device *rbd_dev, u32 which,
3399 u64 *snap_size, u64 *snap_features)
3401 if (rbd_dev->image_format == 1)
3402 return rbd_dev_v1_snap_info(rbd_dev, which,
3403 snap_size, snap_features);
3404 if (rbd_dev->image_format == 2)
3405 return rbd_dev_v2_snap_info(rbd_dev, which,
3406 snap_size, snap_features);
3407 return ERR_PTR(-EINVAL);
3410 static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev, u64 *hver)
3415 down_write(&rbd_dev->header_rwsem);
3417 /* Grab old order first, to see if it changes */
3419 obj_order = rbd_dev->header.obj_order,
3420 ret = rbd_dev_v2_image_size(rbd_dev);
3423 if (rbd_dev->header.obj_order != obj_order) {
3427 rbd_update_mapping_size(rbd_dev);
3429 ret = rbd_dev_v2_snap_context(rbd_dev, hver);
3430 dout("rbd_dev_v2_snap_context returned %d\n", ret);
3433 ret = rbd_dev_snaps_update(rbd_dev);
3434 dout("rbd_dev_snaps_update returned %d\n", ret);
3437 ret = rbd_dev_snaps_register(rbd_dev);
3438 dout("rbd_dev_snaps_register returned %d\n", ret);
3440 up_write(&rbd_dev->header_rwsem);
3446 * Scan the rbd device's current snapshot list and compare it to the
3447 * newly-received snapshot context. Remove any existing snapshots
3448 * not present in the new snapshot context. Add a new snapshot for
3449 * any snaphots in the snapshot context not in the current list.
3450 * And verify there are no changes to snapshots we already know
3453 * Assumes the snapshots in the snapshot context are sorted by
3454 * snapshot id, highest id first. (Snapshots in the rbd_dev's list
3455 * are also maintained in that order.)
3457 static int rbd_dev_snaps_update(struct rbd_device *rbd_dev)
3459 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
3460 const u32 snap_count = snapc->num_snaps;
3461 struct list_head *head = &rbd_dev->snaps;
3462 struct list_head *links = head->next;
3465 dout("%s: snap count is %u\n", __func__, (unsigned int) snap_count);
3466 while (index < snap_count || links != head) {
3468 struct rbd_snap *snap;
3471 u64 snap_features = 0;
3473 snap_id = index < snap_count ? snapc->snaps[index]
3475 snap = links != head ? list_entry(links, struct rbd_snap, node)
3477 rbd_assert(!snap || snap->id != CEPH_NOSNAP);
3479 if (snap_id == CEPH_NOSNAP || (snap && snap->id > snap_id)) {
3480 struct list_head *next = links->next;
3483 * A previously-existing snapshot is not in
3484 * the new snap context.
3486 * If the now missing snapshot is the one the
3487 * image is mapped to, clear its exists flag
3488 * so we can avoid sending any more requests
3491 if (rbd_dev->spec->snap_id == snap->id)
3492 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
3493 rbd_remove_snap_dev(snap);
3494 dout("%ssnap id %llu has been removed\n",
3495 rbd_dev->spec->snap_id == snap->id ?
3497 (unsigned long long) snap->id);
3499 /* Done with this list entry; advance */
3505 snap_name = rbd_dev_snap_info(rbd_dev, index,
3506 &snap_size, &snap_features);
3507 if (IS_ERR(snap_name))
3508 return PTR_ERR(snap_name);
3510 dout("entry %u: snap_id = %llu\n", (unsigned int) snap_count,
3511 (unsigned long long) snap_id);
3512 if (!snap || (snap_id != CEPH_NOSNAP && snap->id < snap_id)) {
3513 struct rbd_snap *new_snap;
3515 /* We haven't seen this snapshot before */
3517 new_snap = __rbd_add_snap_dev(rbd_dev, snap_name,
3518 snap_id, snap_size, snap_features);
3519 if (IS_ERR(new_snap)) {
3520 int err = PTR_ERR(new_snap);
3522 dout(" failed to add dev, error %d\n", err);
3527 /* New goes before existing, or at end of list */
3529 dout(" added dev%s\n", snap ? "" : " at end\n");
3531 list_add_tail(&new_snap->node, &snap->node);
3533 list_add_tail(&new_snap->node, head);
3535 /* Already have this one */
3537 dout(" already present\n");
3539 rbd_assert(snap->size == snap_size);
3540 rbd_assert(!strcmp(snap->name, snap_name));
3541 rbd_assert(snap->features == snap_features);
3543 /* Done with this list entry; advance */
3545 links = links->next;
3548 /* Advance to the next entry in the snapshot context */
3552 dout("%s: done\n", __func__);
3558 * Scan the list of snapshots and register the devices for any that
3559 * have not already been registered.
3561 static int rbd_dev_snaps_register(struct rbd_device *rbd_dev)
3563 struct rbd_snap *snap;
3566 dout("%s:\n", __func__);
3567 if (WARN_ON(!device_is_registered(&rbd_dev->dev)))
3570 list_for_each_entry(snap, &rbd_dev->snaps, node) {
3571 if (!rbd_snap_registered(snap)) {
3572 ret = rbd_register_snap_dev(snap, &rbd_dev->dev);
3577 dout("%s: returning %d\n", __func__, ret);
3582 static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
3587 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
3589 dev = &rbd_dev->dev;
3590 dev->bus = &rbd_bus_type;
3591 dev->type = &rbd_device_type;
3592 dev->parent = &rbd_root_dev;
3593 dev->release = rbd_dev_release;
3594 dev_set_name(dev, "%d", rbd_dev->dev_id);
3595 ret = device_register(dev);
3597 mutex_unlock(&ctl_mutex);
3602 static void rbd_bus_del_dev(struct rbd_device *rbd_dev)
3604 device_unregister(&rbd_dev->dev);
3607 static atomic64_t rbd_dev_id_max = ATOMIC64_INIT(0);
3610 * Get a unique rbd identifier for the given new rbd_dev, and add
3611 * the rbd_dev to the global list. The minimum rbd id is 1.
3613 static void rbd_dev_id_get(struct rbd_device *rbd_dev)
3615 rbd_dev->dev_id = atomic64_inc_return(&rbd_dev_id_max);
3617 spin_lock(&rbd_dev_list_lock);
3618 list_add_tail(&rbd_dev->node, &rbd_dev_list);
3619 spin_unlock(&rbd_dev_list_lock);
3620 dout("rbd_dev %p given dev id %llu\n", rbd_dev,
3621 (unsigned long long) rbd_dev->dev_id);
3625 * Remove an rbd_dev from the global list, and record that its
3626 * identifier is no longer in use.
3628 static void rbd_dev_id_put(struct rbd_device *rbd_dev)
3630 struct list_head *tmp;
3631 int rbd_id = rbd_dev->dev_id;
3634 rbd_assert(rbd_id > 0);
3636 dout("rbd_dev %p released dev id %llu\n", rbd_dev,
3637 (unsigned long long) rbd_dev->dev_id);
3638 spin_lock(&rbd_dev_list_lock);
3639 list_del_init(&rbd_dev->node);
3642 * If the id being "put" is not the current maximum, there
3643 * is nothing special we need to do.
3645 if (rbd_id != atomic64_read(&rbd_dev_id_max)) {
3646 spin_unlock(&rbd_dev_list_lock);
3651 * We need to update the current maximum id. Search the
3652 * list to find out what it is. We're more likely to find
3653 * the maximum at the end, so search the list backward.
3656 list_for_each_prev(tmp, &rbd_dev_list) {
3657 struct rbd_device *rbd_dev;
3659 rbd_dev = list_entry(tmp, struct rbd_device, node);
3660 if (rbd_dev->dev_id > max_id)
3661 max_id = rbd_dev->dev_id;
3663 spin_unlock(&rbd_dev_list_lock);
3666 * The max id could have been updated by rbd_dev_id_get(), in
3667 * which case it now accurately reflects the new maximum.
3668 * Be careful not to overwrite the maximum value in that
3671 atomic64_cmpxchg(&rbd_dev_id_max, rbd_id, max_id);
3672 dout(" max dev id has been reset\n");
3676 * Skips over white space at *buf, and updates *buf to point to the
3677 * first found non-space character (if any). Returns the length of
3678 * the token (string of non-white space characters) found. Note
3679 * that *buf must be terminated with '\0'.
3681 static inline size_t next_token(const char **buf)
3684 * These are the characters that produce nonzero for
3685 * isspace() in the "C" and "POSIX" locales.
3687 const char *spaces = " \f\n\r\t\v";
3689 *buf += strspn(*buf, spaces); /* Find start of token */
3691 return strcspn(*buf, spaces); /* Return token length */
3695 * Finds the next token in *buf, and if the provided token buffer is
3696 * big enough, copies the found token into it. The result, if
3697 * copied, is guaranteed to be terminated with '\0'. Note that *buf
3698 * must be terminated with '\0' on entry.
3700 * Returns the length of the token found (not including the '\0').
3701 * Return value will be 0 if no token is found, and it will be >=
3702 * token_size if the token would not fit.
3704 * The *buf pointer will be updated to point beyond the end of the
3705 * found token. Note that this occurs even if the token buffer is
3706 * too small to hold it.
3708 static inline size_t copy_token(const char **buf,
3714 len = next_token(buf);
3715 if (len < token_size) {
3716 memcpy(token, *buf, len);
3717 *(token + len) = '\0';
3725 * Finds the next token in *buf, dynamically allocates a buffer big
3726 * enough to hold a copy of it, and copies the token into the new
3727 * buffer. The copy is guaranteed to be terminated with '\0'. Note
3728 * that a duplicate buffer is created even for a zero-length token.
3730 * Returns a pointer to the newly-allocated duplicate, or a null
3731 * pointer if memory for the duplicate was not available. If
3732 * the lenp argument is a non-null pointer, the length of the token
3733 * (not including the '\0') is returned in *lenp.
3735 * If successful, the *buf pointer will be updated to point beyond
3736 * the end of the found token.
3738 * Note: uses GFP_KERNEL for allocation.
3740 static inline char *dup_token(const char **buf, size_t *lenp)
3745 len = next_token(buf);
3746 dup = kmemdup(*buf, len + 1, GFP_KERNEL);
3749 *(dup + len) = '\0';
3759 * Parse the options provided for an "rbd add" (i.e., rbd image
3760 * mapping) request. These arrive via a write to /sys/bus/rbd/add,
3761 * and the data written is passed here via a NUL-terminated buffer.
3762 * Returns 0 if successful or an error code otherwise.
3764 * The information extracted from these options is recorded in
3765 * the other parameters which return dynamically-allocated
3768 * The address of a pointer that will refer to a ceph options
3769 * structure. Caller must release the returned pointer using
3770 * ceph_destroy_options() when it is no longer needed.
3772 * Address of an rbd options pointer. Fully initialized by
3773 * this function; caller must release with kfree().
3775 * Address of an rbd image specification pointer. Fully
3776 * initialized by this function based on parsed options.
3777 * Caller must release with rbd_spec_put().
3779 * The options passed take this form:
3780 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
3783 * A comma-separated list of one or more monitor addresses.
3784 * A monitor address is an ip address, optionally followed
3785 * by a port number (separated by a colon).
3786 * I.e.: ip1[:port1][,ip2[:port2]...]
3788 * A comma-separated list of ceph and/or rbd options.
3790 * The name of the rados pool containing the rbd image.
3792 * The name of the image in that pool to map.
3794 * An optional snapshot id. If provided, the mapping will
3795 * present data from the image at the time that snapshot was
3796 * created. The image head is used if no snapshot id is
3797 * provided. Snapshot mappings are always read-only.
3799 static int rbd_add_parse_args(const char *buf,
3800 struct ceph_options **ceph_opts,
3801 struct rbd_options **opts,
3802 struct rbd_spec **rbd_spec)
3806 const char *mon_addrs;
3807 size_t mon_addrs_size;
3808 struct rbd_spec *spec = NULL;
3809 struct rbd_options *rbd_opts = NULL;
3810 struct ceph_options *copts;
3813 /* The first four tokens are required */
3815 len = next_token(&buf);
3817 rbd_warn(NULL, "no monitor address(es) provided");
3821 mon_addrs_size = len + 1;
3825 options = dup_token(&buf, NULL);
3829 rbd_warn(NULL, "no options provided");
3833 spec = rbd_spec_alloc();
3837 spec->pool_name = dup_token(&buf, NULL);
3838 if (!spec->pool_name)
3840 if (!*spec->pool_name) {
3841 rbd_warn(NULL, "no pool name provided");
3845 spec->image_name = dup_token(&buf, NULL);
3846 if (!spec->image_name)
3848 if (!*spec->image_name) {
3849 rbd_warn(NULL, "no image name provided");
3854 * Snapshot name is optional; default is to use "-"
3855 * (indicating the head/no snapshot).
3857 len = next_token(&buf);
3859 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
3860 len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
3861 } else if (len > RBD_MAX_SNAP_NAME_LEN) {
3862 ret = -ENAMETOOLONG;
3865 spec->snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
3866 if (!spec->snap_name)
3868 *(spec->snap_name + len) = '\0';
3870 /* Initialize all rbd options to the defaults */
3872 rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL);
3876 rbd_opts->read_only = RBD_READ_ONLY_DEFAULT;
3878 copts = ceph_parse_options(options, mon_addrs,
3879 mon_addrs + mon_addrs_size - 1,
3880 parse_rbd_opts_token, rbd_opts);
3881 if (IS_ERR(copts)) {
3882 ret = PTR_ERR(copts);
3903 * An rbd format 2 image has a unique identifier, distinct from the
3904 * name given to it by the user. Internally, that identifier is
3905 * what's used to specify the names of objects related to the image.
3907 * A special "rbd id" object is used to map an rbd image name to its
3908 * id. If that object doesn't exist, then there is no v2 rbd image
3909 * with the supplied name.
3911 * This function will record the given rbd_dev's image_id field if
3912 * it can be determined, and in that case will return 0. If any
3913 * errors occur a negative errno will be returned and the rbd_dev's
3914 * image_id field will be unchanged (and should be NULL).
3916 static int rbd_dev_image_id(struct rbd_device *rbd_dev)
3924 /* If we already have it we don't need to look it up */
3926 if (rbd_dev->spec->image_id)
3930 * When probing a parent image, the image id is already
3931 * known (and the image name likely is not). There's no
3932 * need to fetch the image id again in this case.
3934 if (rbd_dev->spec->image_id)
3938 * First, see if the format 2 image id file exists, and if
3939 * so, get the image's persistent id from it.
3941 size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name);
3942 object_name = kmalloc(size, GFP_NOIO);
3945 sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name);
3946 dout("rbd id object name is %s\n", object_name);
3948 /* Response will be an encoded string, which includes a length */
3950 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
3951 response = kzalloc(size, GFP_NOIO);
3957 ret = rbd_obj_method_sync(rbd_dev, object_name,
3960 response, RBD_IMAGE_ID_LEN_MAX, NULL);
3961 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3966 rbd_dev->spec->image_id = ceph_extract_encoded_string(&p,
3967 p + RBD_IMAGE_ID_LEN_MAX,
3969 if (IS_ERR(rbd_dev->spec->image_id)) {
3970 ret = PTR_ERR(rbd_dev->spec->image_id);
3971 rbd_dev->spec->image_id = NULL;
3973 dout("image_id is %s\n", rbd_dev->spec->image_id);
3982 static int rbd_dev_v1_probe(struct rbd_device *rbd_dev)
3987 /* Version 1 images have no id; empty string is used */
3989 rbd_dev->spec->image_id = kstrdup("", GFP_KERNEL);
3990 if (!rbd_dev->spec->image_id)
3993 /* Record the header object name for this rbd image. */
3995 size = strlen(rbd_dev->spec->image_name) + sizeof (RBD_SUFFIX);
3996 rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
3997 if (!rbd_dev->header_name) {
4001 sprintf(rbd_dev->header_name, "%s%s",
4002 rbd_dev->spec->image_name, RBD_SUFFIX);
4004 /* Populate rbd image metadata */
4006 ret = rbd_read_header(rbd_dev, &rbd_dev->header);
4010 /* Version 1 images have no parent (no layering) */
4012 rbd_dev->parent_spec = NULL;
4013 rbd_dev->parent_overlap = 0;
4015 rbd_dev->image_format = 1;
4017 dout("discovered version 1 image, header name is %s\n",
4018 rbd_dev->header_name);
4023 kfree(rbd_dev->header_name);
4024 rbd_dev->header_name = NULL;
4025 kfree(rbd_dev->spec->image_id);
4026 rbd_dev->spec->image_id = NULL;
4031 static int rbd_dev_v2_probe(struct rbd_device *rbd_dev)
4038 * Image id was filled in by the caller. Record the header
4039 * object name for this rbd image.
4041 size = sizeof (RBD_HEADER_PREFIX) + strlen(rbd_dev->spec->image_id);
4042 rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
4043 if (!rbd_dev->header_name)
4045 sprintf(rbd_dev->header_name, "%s%s",
4046 RBD_HEADER_PREFIX, rbd_dev->spec->image_id);
4048 /* Get the size and object order for the image */
4050 ret = rbd_dev_v2_image_size(rbd_dev);
4054 /* Get the object prefix (a.k.a. block_name) for the image */
4056 ret = rbd_dev_v2_object_prefix(rbd_dev);
4060 /* Get the and check features for the image */
4062 ret = rbd_dev_v2_features(rbd_dev);
4066 /* If the image supports layering, get the parent info */
4068 if (rbd_dev->header.features & RBD_FEATURE_LAYERING) {
4069 ret = rbd_dev_v2_parent_info(rbd_dev);
4074 /* crypto and compression type aren't (yet) supported for v2 images */
4076 rbd_dev->header.crypt_type = 0;
4077 rbd_dev->header.comp_type = 0;
4079 /* Get the snapshot context, plus the header version */
4081 ret = rbd_dev_v2_snap_context(rbd_dev, &ver);
4084 rbd_dev->header.obj_version = ver;
4086 rbd_dev->image_format = 2;
4088 dout("discovered version 2 image, header name is %s\n",
4089 rbd_dev->header_name);
4093 rbd_dev->parent_overlap = 0;
4094 rbd_spec_put(rbd_dev->parent_spec);
4095 rbd_dev->parent_spec = NULL;
4096 kfree(rbd_dev->header_name);
4097 rbd_dev->header_name = NULL;
4098 kfree(rbd_dev->header.object_prefix);
4099 rbd_dev->header.object_prefix = NULL;
4104 static int rbd_dev_probe_finish(struct rbd_device *rbd_dev)
4106 struct rbd_device *parent = NULL;
4107 struct rbd_spec *parent_spec = NULL;
4108 struct rbd_client *rbdc = NULL;
4111 /* no need to lock here, as rbd_dev is not registered yet */
4112 ret = rbd_dev_snaps_update(rbd_dev);
4116 ret = rbd_dev_probe_update_spec(rbd_dev);
4120 ret = rbd_dev_set_mapping(rbd_dev);
4124 /* generate unique id: find highest unique id, add one */
4125 rbd_dev_id_get(rbd_dev);
4127 /* Fill in the device name, now that we have its id. */
4128 BUILD_BUG_ON(DEV_NAME_LEN
4129 < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
4130 sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id);
4132 /* Get our block major device number. */
4134 ret = register_blkdev(0, rbd_dev->name);
4137 rbd_dev->major = ret;
4139 /* Set up the blkdev mapping. */
4141 ret = rbd_init_disk(rbd_dev);
4143 goto err_out_blkdev;
4145 ret = rbd_bus_add_dev(rbd_dev);
4150 * At this point cleanup in the event of an error is the job
4151 * of the sysfs code (initiated by rbd_bus_del_dev()).
4153 /* Probe the parent if there is one */
4155 if (rbd_dev->parent_spec) {
4157 * We need to pass a reference to the client and the
4158 * parent spec when creating the parent rbd_dev.
4159 * Images related by parent/child relationships
4160 * always share both.
4162 parent_spec = rbd_spec_get(rbd_dev->parent_spec);
4163 rbdc = __rbd_get_client(rbd_dev->rbd_client);
4165 parent = rbd_dev_create(rbdc, parent_spec);
4170 rbdc = NULL; /* parent now owns reference */
4171 parent_spec = NULL; /* parent now owns reference */
4172 ret = rbd_dev_probe(parent);
4174 goto err_out_parent;
4175 rbd_dev->parent = parent;
4178 down_write(&rbd_dev->header_rwsem);
4179 ret = rbd_dev_snaps_register(rbd_dev);
4180 up_write(&rbd_dev->header_rwsem);
4184 ret = rbd_dev_header_watch_sync(rbd_dev, 1);
4188 /* Everything's ready. Announce the disk to the world. */
4190 add_disk(rbd_dev->disk);
4192 pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name,
4193 (unsigned long long) rbd_dev->mapping.size);
4198 rbd_dev_destroy(parent);
4200 rbd_spec_put(parent_spec);
4201 rbd_put_client(rbdc);
4203 /* this will also clean up rest of rbd_dev stuff */
4205 rbd_bus_del_dev(rbd_dev);
4209 rbd_free_disk(rbd_dev);
4211 unregister_blkdev(rbd_dev->major, rbd_dev->name);
4213 rbd_dev_id_put(rbd_dev);
4215 rbd_remove_all_snaps(rbd_dev);
4221 * Probe for the existence of the header object for the given rbd
4222 * device. For format 2 images this includes determining the image
4225 static int rbd_dev_probe(struct rbd_device *rbd_dev)
4230 * Get the id from the image id object. If it's not a
4231 * format 2 image, we'll get ENOENT back, and we'll assume
4232 * it's a format 1 image.
4234 ret = rbd_dev_image_id(rbd_dev);
4236 ret = rbd_dev_v1_probe(rbd_dev);
4238 ret = rbd_dev_v2_probe(rbd_dev);
4240 dout("probe failed, returning %d\n", ret);
4245 ret = rbd_dev_probe_finish(rbd_dev);
4247 rbd_header_free(&rbd_dev->header);
4252 static ssize_t rbd_add(struct bus_type *bus,
4256 struct rbd_device *rbd_dev = NULL;
4257 struct ceph_options *ceph_opts = NULL;
4258 struct rbd_options *rbd_opts = NULL;
4259 struct rbd_spec *spec = NULL;
4260 struct rbd_client *rbdc;
4261 struct ceph_osd_client *osdc;
4264 if (!try_module_get(THIS_MODULE))
4267 /* parse add command */
4268 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
4270 goto err_out_module;
4272 rbdc = rbd_get_client(ceph_opts);
4277 ceph_opts = NULL; /* rbd_dev client now owns this */
4280 osdc = &rbdc->client->osdc;
4281 rc = ceph_pg_poolid_by_name(osdc->osdmap, spec->pool_name);
4283 goto err_out_client;
4284 spec->pool_id = (u64) rc;
4286 /* The ceph file layout needs to fit pool id in 32 bits */
4288 if (WARN_ON(spec->pool_id > (u64) U32_MAX)) {
4290 goto err_out_client;
4293 rbd_dev = rbd_dev_create(rbdc, spec);
4295 goto err_out_client;
4296 rbdc = NULL; /* rbd_dev now owns this */
4297 spec = NULL; /* rbd_dev now owns this */
4299 rbd_dev->mapping.read_only = rbd_opts->read_only;
4301 rbd_opts = NULL; /* done with this */
4303 rc = rbd_dev_probe(rbd_dev);
4305 goto err_out_rbd_dev;
4309 rbd_dev_destroy(rbd_dev);
4311 rbd_put_client(rbdc);
4314 ceph_destroy_options(ceph_opts);
4318 module_put(THIS_MODULE);
4320 dout("Error adding device %s\n", buf);
4322 return (ssize_t) rc;
4325 static struct rbd_device *__rbd_get_dev(unsigned long dev_id)
4327 struct list_head *tmp;
4328 struct rbd_device *rbd_dev;
4330 spin_lock(&rbd_dev_list_lock);
4331 list_for_each(tmp, &rbd_dev_list) {
4332 rbd_dev = list_entry(tmp, struct rbd_device, node);
4333 if (rbd_dev->dev_id == dev_id) {
4334 spin_unlock(&rbd_dev_list_lock);
4338 spin_unlock(&rbd_dev_list_lock);
4342 static void rbd_dev_release(struct device *dev)
4344 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4346 if (rbd_dev->watch_event)
4347 rbd_dev_header_watch_sync(rbd_dev, 0);
4349 /* clean up and free blkdev */
4350 rbd_free_disk(rbd_dev);
4351 unregister_blkdev(rbd_dev->major, rbd_dev->name);
4353 /* release allocated disk header fields */
4354 rbd_header_free(&rbd_dev->header);
4356 /* done with the id, and with the rbd_dev */
4357 rbd_dev_id_put(rbd_dev);
4358 rbd_assert(rbd_dev->rbd_client != NULL);
4359 rbd_dev_destroy(rbd_dev);
4361 /* release module ref */
4362 module_put(THIS_MODULE);
4365 static void __rbd_remove(struct rbd_device *rbd_dev)
4367 rbd_remove_all_snaps(rbd_dev);
4368 rbd_bus_del_dev(rbd_dev);
4371 static ssize_t rbd_remove(struct bus_type *bus,
4375 struct rbd_device *rbd_dev = NULL;
4380 rc = strict_strtoul(buf, 10, &ul);
4384 /* convert to int; abort if we lost anything in the conversion */
4385 target_id = (int) ul;
4386 if (target_id != ul)
4389 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
4391 rbd_dev = __rbd_get_dev(target_id);
4397 spin_lock_irq(&rbd_dev->lock);
4398 if (rbd_dev->open_count)
4401 set_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags);
4402 spin_unlock_irq(&rbd_dev->lock);
4406 while (rbd_dev->parent_spec) {
4407 struct rbd_device *first = rbd_dev;
4408 struct rbd_device *second = first->parent;
4409 struct rbd_device *third;
4412 * Follow to the parent with no grandparent and
4415 while (second && (third = second->parent)) {
4419 __rbd_remove(second);
4420 rbd_spec_put(first->parent_spec);
4421 first->parent_spec = NULL;
4422 first->parent_overlap = 0;
4423 first->parent = NULL;
4425 __rbd_remove(rbd_dev);
4428 mutex_unlock(&ctl_mutex);
4434 * create control files in sysfs
4437 static int rbd_sysfs_init(void)
4441 ret = device_register(&rbd_root_dev);
4445 ret = bus_register(&rbd_bus_type);
4447 device_unregister(&rbd_root_dev);
4452 static void rbd_sysfs_cleanup(void)
4454 bus_unregister(&rbd_bus_type);
4455 device_unregister(&rbd_root_dev);
4458 static int __init rbd_init(void)
4462 if (!libceph_compatible(NULL)) {
4463 rbd_warn(NULL, "libceph incompatibility (quitting)");
4467 rc = rbd_sysfs_init();
4470 pr_info("loaded " RBD_DRV_NAME_LONG "\n");
4474 static void __exit rbd_exit(void)
4476 rbd_sysfs_cleanup();
4479 module_init(rbd_init);
4480 module_exit(rbd_exit);
4482 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
4483 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
4484 MODULE_DESCRIPTION("rados block device");
4486 /* following authorship retained from original osdblk.c */
4487 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
4489 MODULE_LICENSE("GPL");