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
78 /* Features supported by this (client software) implementation. */
80 #define RBD_FEATURES_ALL (0)
83 * An RBD device name will be "rbd#", where the "rbd" comes from
84 * RBD_DRV_NAME above, and # is a unique integer identifier.
85 * MAX_INT_FORMAT_WIDTH is used in ensuring DEV_NAME_LEN is big
86 * enough to hold all possible device names.
88 #define DEV_NAME_LEN 32
89 #define MAX_INT_FORMAT_WIDTH ((5 * sizeof (int)) / 2 + 1)
92 * block device image metadata (in-memory version)
94 struct rbd_image_header {
95 /* These four fields never change for a given rbd image */
102 /* The remaining fields need to be updated occasionally */
104 struct ceph_snap_context *snapc;
112 * An rbd image specification.
114 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely
115 * identify an image. Each rbd_dev structure includes a pointer to
116 * an rbd_spec structure that encapsulates this identity.
118 * Each of the id's in an rbd_spec has an associated name. For a
119 * user-mapped image, the names are supplied and the id's associated
120 * with them are looked up. For a layered image, a parent image is
121 * defined by the tuple, and the names are looked up.
123 * An rbd_dev structure contains a parent_spec pointer which is
124 * non-null if the image it represents is a child in a layered
125 * image. This pointer will refer to the rbd_spec structure used
126 * by the parent rbd_dev for its own identity (i.e., the structure
127 * is shared between the parent and child).
129 * Since these structures are populated once, during the discovery
130 * phase of image construction, they are effectively immutable so
131 * we make no effort to synchronize access to them.
133 * Note that code herein does not assume the image name is known (it
134 * could be a null pointer).
150 * an instance of the client. multiple devices may share an rbd client.
153 struct ceph_client *client;
155 struct list_head node;
158 struct rbd_img_request;
159 typedef void (*rbd_img_callback_t)(struct rbd_img_request *);
161 #define BAD_WHICH U32_MAX /* Good which or bad which, which? */
163 struct rbd_obj_request;
164 typedef void (*rbd_obj_callback_t)(struct rbd_obj_request *);
166 enum obj_request_type {
167 OBJ_REQUEST_NODATA, OBJ_REQUEST_BIO, OBJ_REQUEST_PAGES
170 struct rbd_obj_request {
171 const char *object_name;
172 u64 offset; /* object start byte */
173 u64 length; /* bytes from offset */
175 struct rbd_img_request *img_request;
176 struct list_head links; /* img_request->obj_requests */
177 u32 which; /* posn image request list */
179 enum obj_request_type type;
181 struct bio *bio_list;
188 struct ceph_osd_request *osd_req;
190 u64 xferred; /* bytes transferred */
195 rbd_obj_callback_t callback;
196 struct completion completion;
201 struct rbd_img_request {
203 struct rbd_device *rbd_dev;
204 u64 offset; /* starting image byte offset */
205 u64 length; /* byte count from offset */
206 bool write_request; /* false for read */
208 struct ceph_snap_context *snapc; /* for writes */
209 u64 snap_id; /* for reads */
211 spinlock_t completion_lock;/* protects next_completion */
213 rbd_img_callback_t callback;
215 u32 obj_request_count;
216 struct list_head obj_requests; /* rbd_obj_request structs */
221 #define for_each_obj_request(ireq, oreq) \
222 list_for_each_entry(oreq, &(ireq)->obj_requests, links)
223 #define for_each_obj_request_from(ireq, oreq) \
224 list_for_each_entry_from(oreq, &(ireq)->obj_requests, links)
225 #define for_each_obj_request_safe(ireq, oreq, n) \
226 list_for_each_entry_safe_reverse(oreq, n, &(ireq)->obj_requests, links)
232 struct list_head node;
247 int dev_id; /* blkdev unique id */
249 int major; /* blkdev assigned major */
250 struct gendisk *disk; /* blkdev's gendisk and rq */
252 u32 image_format; /* Either 1 or 2 */
253 struct rbd_client *rbd_client;
255 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */
257 spinlock_t lock; /* queue, flags, open_count */
259 struct rbd_image_header header;
260 unsigned long flags; /* possibly lock protected */
261 struct rbd_spec *spec;
265 struct ceph_file_layout layout;
267 struct ceph_osd_event *watch_event;
268 struct rbd_obj_request *watch_request;
270 struct rbd_spec *parent_spec;
273 /* protects updating the header */
274 struct rw_semaphore header_rwsem;
276 struct rbd_mapping mapping;
278 struct list_head node;
280 /* list of snapshots */
281 struct list_head snaps;
285 unsigned long open_count; /* protected by lock */
289 * Flag bits for rbd_dev->flags. If atomicity is required,
290 * rbd_dev->lock is used to protect access.
292 * Currently, only the "removing" flag (which is coupled with the
293 * "open_count" field) requires atomic access.
296 RBD_DEV_FLAG_EXISTS, /* mapped snapshot has not been deleted */
297 RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */
300 static DEFINE_MUTEX(ctl_mutex); /* Serialize open/close/setup/teardown */
302 static LIST_HEAD(rbd_dev_list); /* devices */
303 static DEFINE_SPINLOCK(rbd_dev_list_lock);
305 static LIST_HEAD(rbd_client_list); /* clients */
306 static DEFINE_SPINLOCK(rbd_client_list_lock);
308 static int rbd_dev_snaps_update(struct rbd_device *rbd_dev);
309 static int rbd_dev_snaps_register(struct rbd_device *rbd_dev);
311 static void rbd_dev_release(struct device *dev);
312 static void rbd_remove_snap_dev(struct rbd_snap *snap);
314 static ssize_t rbd_add(struct bus_type *bus, const char *buf,
316 static ssize_t rbd_remove(struct bus_type *bus, const char *buf,
319 static struct bus_attribute rbd_bus_attrs[] = {
320 __ATTR(add, S_IWUSR, NULL, rbd_add),
321 __ATTR(remove, S_IWUSR, NULL, rbd_remove),
325 static struct bus_type rbd_bus_type = {
327 .bus_attrs = rbd_bus_attrs,
330 static void rbd_root_dev_release(struct device *dev)
334 static struct device rbd_root_dev = {
336 .release = rbd_root_dev_release,
339 static __printf(2, 3)
340 void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...)
342 struct va_format vaf;
350 printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf);
351 else if (rbd_dev->disk)
352 printk(KERN_WARNING "%s: %s: %pV\n",
353 RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf);
354 else if (rbd_dev->spec && rbd_dev->spec->image_name)
355 printk(KERN_WARNING "%s: image %s: %pV\n",
356 RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf);
357 else if (rbd_dev->spec && rbd_dev->spec->image_id)
358 printk(KERN_WARNING "%s: id %s: %pV\n",
359 RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf);
361 printk(KERN_WARNING "%s: rbd_dev %p: %pV\n",
362 RBD_DRV_NAME, rbd_dev, &vaf);
367 #define rbd_assert(expr) \
368 if (unlikely(!(expr))) { \
369 printk(KERN_ERR "\nAssertion failure in %s() " \
371 "\trbd_assert(%s);\n\n", \
372 __func__, __LINE__, #expr); \
375 #else /* !RBD_DEBUG */
376 # define rbd_assert(expr) ((void) 0)
377 #endif /* !RBD_DEBUG */
379 static int rbd_dev_refresh(struct rbd_device *rbd_dev, u64 *hver);
380 static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev, u64 *hver);
382 static int rbd_open(struct block_device *bdev, fmode_t mode)
384 struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
385 bool removing = false;
387 if ((mode & FMODE_WRITE) && rbd_dev->mapping.read_only)
390 spin_lock_irq(&rbd_dev->lock);
391 if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags))
394 rbd_dev->open_count++;
395 spin_unlock_irq(&rbd_dev->lock);
399 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
400 (void) get_device(&rbd_dev->dev);
401 set_device_ro(bdev, rbd_dev->mapping.read_only);
402 mutex_unlock(&ctl_mutex);
407 static int rbd_release(struct gendisk *disk, fmode_t mode)
409 struct rbd_device *rbd_dev = disk->private_data;
410 unsigned long open_count_before;
412 spin_lock_irq(&rbd_dev->lock);
413 open_count_before = rbd_dev->open_count--;
414 spin_unlock_irq(&rbd_dev->lock);
415 rbd_assert(open_count_before > 0);
417 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
418 put_device(&rbd_dev->dev);
419 mutex_unlock(&ctl_mutex);
424 static const struct block_device_operations rbd_bd_ops = {
425 .owner = THIS_MODULE,
427 .release = rbd_release,
431 * Initialize an rbd client instance.
434 static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
436 struct rbd_client *rbdc;
439 dout("%s:\n", __func__);
440 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
444 kref_init(&rbdc->kref);
445 INIT_LIST_HEAD(&rbdc->node);
447 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
449 rbdc->client = ceph_create_client(ceph_opts, rbdc, 0, 0);
450 if (IS_ERR(rbdc->client))
452 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
454 ret = ceph_open_session(rbdc->client);
458 spin_lock(&rbd_client_list_lock);
459 list_add_tail(&rbdc->node, &rbd_client_list);
460 spin_unlock(&rbd_client_list_lock);
462 mutex_unlock(&ctl_mutex);
463 dout("%s: rbdc %p\n", __func__, rbdc);
468 ceph_destroy_client(rbdc->client);
470 mutex_unlock(&ctl_mutex);
474 ceph_destroy_options(ceph_opts);
475 dout("%s: error %d\n", __func__, ret);
481 * Find a ceph client with specific addr and configuration. If
482 * found, bump its reference count.
484 static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
486 struct rbd_client *client_node;
489 if (ceph_opts->flags & CEPH_OPT_NOSHARE)
492 spin_lock(&rbd_client_list_lock);
493 list_for_each_entry(client_node, &rbd_client_list, node) {
494 if (!ceph_compare_options(ceph_opts, client_node->client)) {
495 kref_get(&client_node->kref);
500 spin_unlock(&rbd_client_list_lock);
502 return found ? client_node : NULL;
512 /* string args above */
515 /* Boolean args above */
519 static match_table_t rbd_opts_tokens = {
521 /* string args above */
522 {Opt_read_only, "read_only"},
523 {Opt_read_only, "ro"}, /* Alternate spelling */
524 {Opt_read_write, "read_write"},
525 {Opt_read_write, "rw"}, /* Alternate spelling */
526 /* Boolean args above */
534 #define RBD_READ_ONLY_DEFAULT false
536 static int parse_rbd_opts_token(char *c, void *private)
538 struct rbd_options *rbd_opts = private;
539 substring_t argstr[MAX_OPT_ARGS];
540 int token, intval, ret;
542 token = match_token(c, rbd_opts_tokens, argstr);
546 if (token < Opt_last_int) {
547 ret = match_int(&argstr[0], &intval);
549 pr_err("bad mount option arg (not int) "
553 dout("got int token %d val %d\n", token, intval);
554 } else if (token > Opt_last_int && token < Opt_last_string) {
555 dout("got string token %d val %s\n", token,
557 } else if (token > Opt_last_string && token < Opt_last_bool) {
558 dout("got Boolean token %d\n", token);
560 dout("got token %d\n", token);
565 rbd_opts->read_only = true;
568 rbd_opts->read_only = false;
578 * Get a ceph client with specific addr and configuration, if one does
579 * not exist create it.
581 static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
583 struct rbd_client *rbdc;
585 rbdc = rbd_client_find(ceph_opts);
586 if (rbdc) /* using an existing client */
587 ceph_destroy_options(ceph_opts);
589 rbdc = rbd_client_create(ceph_opts);
595 * Destroy ceph client
597 * Caller must hold rbd_client_list_lock.
599 static void rbd_client_release(struct kref *kref)
601 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
603 dout("%s: rbdc %p\n", __func__, rbdc);
604 spin_lock(&rbd_client_list_lock);
605 list_del(&rbdc->node);
606 spin_unlock(&rbd_client_list_lock);
608 ceph_destroy_client(rbdc->client);
613 * Drop reference to ceph client node. If it's not referenced anymore, release
616 static void rbd_put_client(struct rbd_client *rbdc)
619 kref_put(&rbdc->kref, rbd_client_release);
622 static bool rbd_image_format_valid(u32 image_format)
624 return image_format == 1 || image_format == 2;
627 static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
632 /* The header has to start with the magic rbd header text */
633 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
636 /* The bio layer requires at least sector-sized I/O */
638 if (ondisk->options.order < SECTOR_SHIFT)
641 /* If we use u64 in a few spots we may be able to loosen this */
643 if (ondisk->options.order > 8 * sizeof (int) - 1)
647 * The size of a snapshot header has to fit in a size_t, and
648 * that limits the number of snapshots.
650 snap_count = le32_to_cpu(ondisk->snap_count);
651 size = SIZE_MAX - sizeof (struct ceph_snap_context);
652 if (snap_count > size / sizeof (__le64))
656 * Not only that, but the size of the entire the snapshot
657 * header must also be representable in a size_t.
659 size -= snap_count * sizeof (__le64);
660 if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
667 * Create a new header structure, translate header format from the on-disk
670 static int rbd_header_from_disk(struct rbd_image_header *header,
671 struct rbd_image_header_ondisk *ondisk)
678 memset(header, 0, sizeof (*header));
680 snap_count = le32_to_cpu(ondisk->snap_count);
682 len = strnlen(ondisk->object_prefix, sizeof (ondisk->object_prefix));
683 header->object_prefix = kmalloc(len + 1, GFP_KERNEL);
684 if (!header->object_prefix)
686 memcpy(header->object_prefix, ondisk->object_prefix, len);
687 header->object_prefix[len] = '\0';
690 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);
692 /* Save a copy of the snapshot names */
694 if (snap_names_len > (u64) SIZE_MAX)
696 header->snap_names = kmalloc(snap_names_len, GFP_KERNEL);
697 if (!header->snap_names)
700 * Note that rbd_dev_v1_header_read() guarantees
701 * the ondisk buffer we're working with has
702 * snap_names_len bytes beyond the end of the
703 * snapshot id array, this memcpy() is safe.
705 memcpy(header->snap_names, &ondisk->snaps[snap_count],
708 /* Record each snapshot's size */
710 size = snap_count * sizeof (*header->snap_sizes);
711 header->snap_sizes = kmalloc(size, GFP_KERNEL);
712 if (!header->snap_sizes)
714 for (i = 0; i < snap_count; i++)
715 header->snap_sizes[i] =
716 le64_to_cpu(ondisk->snaps[i].image_size);
718 WARN_ON(ondisk->snap_names_len);
719 header->snap_names = NULL;
720 header->snap_sizes = NULL;
723 header->features = 0; /* No features support in v1 images */
724 header->obj_order = ondisk->options.order;
725 header->crypt_type = ondisk->options.crypt_type;
726 header->comp_type = ondisk->options.comp_type;
728 /* Allocate and fill in the snapshot context */
730 header->image_size = le64_to_cpu(ondisk->image_size);
731 size = sizeof (struct ceph_snap_context);
732 size += snap_count * sizeof (header->snapc->snaps[0]);
733 header->snapc = kzalloc(size, GFP_KERNEL);
737 atomic_set(&header->snapc->nref, 1);
738 header->snapc->seq = le64_to_cpu(ondisk->snap_seq);
739 header->snapc->num_snaps = snap_count;
740 for (i = 0; i < snap_count; i++)
741 header->snapc->snaps[i] =
742 le64_to_cpu(ondisk->snaps[i].id);
747 kfree(header->snap_sizes);
748 header->snap_sizes = NULL;
749 kfree(header->snap_names);
750 header->snap_names = NULL;
751 kfree(header->object_prefix);
752 header->object_prefix = NULL;
757 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
759 struct rbd_snap *snap;
761 if (snap_id == CEPH_NOSNAP)
762 return RBD_SNAP_HEAD_NAME;
764 list_for_each_entry(snap, &rbd_dev->snaps, node)
765 if (snap_id == snap->id)
771 static int snap_by_name(struct rbd_device *rbd_dev, const char *snap_name)
774 struct rbd_snap *snap;
776 list_for_each_entry(snap, &rbd_dev->snaps, node) {
777 if (!strcmp(snap_name, snap->name)) {
778 rbd_dev->spec->snap_id = snap->id;
779 rbd_dev->mapping.size = snap->size;
780 rbd_dev->mapping.features = snap->features;
789 static int rbd_dev_set_mapping(struct rbd_device *rbd_dev)
793 if (!memcmp(rbd_dev->spec->snap_name, RBD_SNAP_HEAD_NAME,
794 sizeof (RBD_SNAP_HEAD_NAME))) {
795 rbd_dev->spec->snap_id = CEPH_NOSNAP;
796 rbd_dev->mapping.size = rbd_dev->header.image_size;
797 rbd_dev->mapping.features = rbd_dev->header.features;
800 ret = snap_by_name(rbd_dev, rbd_dev->spec->snap_name);
803 rbd_dev->mapping.read_only = true;
805 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
811 static void rbd_header_free(struct rbd_image_header *header)
813 kfree(header->object_prefix);
814 header->object_prefix = NULL;
815 kfree(header->snap_sizes);
816 header->snap_sizes = NULL;
817 kfree(header->snap_names);
818 header->snap_names = NULL;
819 ceph_put_snap_context(header->snapc);
820 header->snapc = NULL;
823 static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset)
829 name = kmalloc(MAX_OBJ_NAME_SIZE + 1, GFP_NOIO);
832 segment = offset >> rbd_dev->header.obj_order;
833 ret = snprintf(name, MAX_OBJ_NAME_SIZE + 1, "%s.%012llx",
834 rbd_dev->header.object_prefix, segment);
835 if (ret < 0 || ret > MAX_OBJ_NAME_SIZE) {
836 pr_err("error formatting segment name for #%llu (%d)\n",
845 static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset)
847 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
849 return offset & (segment_size - 1);
852 static u64 rbd_segment_length(struct rbd_device *rbd_dev,
853 u64 offset, u64 length)
855 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
857 offset &= segment_size - 1;
859 rbd_assert(length <= U64_MAX - offset);
860 if (offset + length > segment_size)
861 length = segment_size - offset;
867 * returns the size of an object in the image
869 static u64 rbd_obj_bytes(struct rbd_image_header *header)
871 return 1 << header->obj_order;
878 static void bio_chain_put(struct bio *chain)
884 chain = chain->bi_next;
890 * zeros a bio chain, starting at specific offset
892 static void zero_bio_chain(struct bio *chain, int start_ofs)
901 bio_for_each_segment(bv, chain, i) {
902 if (pos + bv->bv_len > start_ofs) {
903 int remainder = max(start_ofs - pos, 0);
904 buf = bvec_kmap_irq(bv, &flags);
905 memset(buf + remainder, 0,
906 bv->bv_len - remainder);
907 bvec_kunmap_irq(buf, &flags);
912 chain = chain->bi_next;
917 * Clone a portion of a bio, starting at the given byte offset
918 * and continuing for the number of bytes indicated.
920 static struct bio *bio_clone_range(struct bio *bio_src,
929 unsigned short end_idx;
933 /* Handle the easy case for the caller */
935 if (!offset && len == bio_src->bi_size)
936 return bio_clone(bio_src, gfpmask);
938 if (WARN_ON_ONCE(!len))
940 if (WARN_ON_ONCE(len > bio_src->bi_size))
942 if (WARN_ON_ONCE(offset > bio_src->bi_size - len))
945 /* Find first affected segment... */
948 __bio_for_each_segment(bv, bio_src, idx, 0) {
949 if (resid < bv->bv_len)
955 /* ...and the last affected segment */
958 __bio_for_each_segment(bv, bio_src, end_idx, idx) {
959 if (resid <= bv->bv_len)
963 vcnt = end_idx - idx + 1;
965 /* Build the clone */
967 bio = bio_alloc(gfpmask, (unsigned int) vcnt);
969 return NULL; /* ENOMEM */
971 bio->bi_bdev = bio_src->bi_bdev;
972 bio->bi_sector = bio_src->bi_sector + (offset >> SECTOR_SHIFT);
973 bio->bi_rw = bio_src->bi_rw;
974 bio->bi_flags |= 1 << BIO_CLONED;
977 * Copy over our part of the bio_vec, then update the first
978 * and last (or only) entries.
980 memcpy(&bio->bi_io_vec[0], &bio_src->bi_io_vec[idx],
981 vcnt * sizeof (struct bio_vec));
982 bio->bi_io_vec[0].bv_offset += voff;
984 bio->bi_io_vec[0].bv_len -= voff;
985 bio->bi_io_vec[vcnt - 1].bv_len = resid;
987 bio->bi_io_vec[0].bv_len = len;
998 * Clone a portion of a bio chain, starting at the given byte offset
999 * into the first bio in the source chain and continuing for the
1000 * number of bytes indicated. The result is another bio chain of
1001 * exactly the given length, or a null pointer on error.
1003 * The bio_src and offset parameters are both in-out. On entry they
1004 * refer to the first source bio and the offset into that bio where
1005 * the start of data to be cloned is located.
1007 * On return, bio_src is updated to refer to the bio in the source
1008 * chain that contains first un-cloned byte, and *offset will
1009 * contain the offset of that byte within that bio.
1011 static struct bio *bio_chain_clone_range(struct bio **bio_src,
1012 unsigned int *offset,
1016 struct bio *bi = *bio_src;
1017 unsigned int off = *offset;
1018 struct bio *chain = NULL;
1021 /* Build up a chain of clone bios up to the limit */
1023 if (!bi || off >= bi->bi_size || !len)
1024 return NULL; /* Nothing to clone */
1028 unsigned int bi_size;
1032 rbd_warn(NULL, "bio_chain exhausted with %u left", len);
1033 goto out_err; /* EINVAL; ran out of bio's */
1035 bi_size = min_t(unsigned int, bi->bi_size - off, len);
1036 bio = bio_clone_range(bi, off, bi_size, gfpmask);
1038 goto out_err; /* ENOMEM */
1041 end = &bio->bi_next;
1044 if (off == bi->bi_size) {
1055 bio_chain_put(chain);
1060 static void rbd_obj_request_get(struct rbd_obj_request *obj_request)
1062 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1063 atomic_read(&obj_request->kref.refcount));
1064 kref_get(&obj_request->kref);
1067 static void rbd_obj_request_destroy(struct kref *kref);
1068 static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
1070 rbd_assert(obj_request != NULL);
1071 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1072 atomic_read(&obj_request->kref.refcount));
1073 kref_put(&obj_request->kref, rbd_obj_request_destroy);
1076 static void rbd_img_request_get(struct rbd_img_request *img_request)
1078 dout("%s: img %p (was %d)\n", __func__, img_request,
1079 atomic_read(&img_request->kref.refcount));
1080 kref_get(&img_request->kref);
1083 static void rbd_img_request_destroy(struct kref *kref);
1084 static void rbd_img_request_put(struct rbd_img_request *img_request)
1086 rbd_assert(img_request != NULL);
1087 dout("%s: img %p (was %d)\n", __func__, img_request,
1088 atomic_read(&img_request->kref.refcount));
1089 kref_put(&img_request->kref, rbd_img_request_destroy);
1092 static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
1093 struct rbd_obj_request *obj_request)
1095 rbd_assert(obj_request->img_request == NULL);
1097 rbd_obj_request_get(obj_request);
1098 obj_request->img_request = img_request;
1099 obj_request->which = img_request->obj_request_count;
1100 rbd_assert(obj_request->which != BAD_WHICH);
1101 img_request->obj_request_count++;
1102 list_add_tail(&obj_request->links, &img_request->obj_requests);
1103 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1104 obj_request->which);
1107 static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
1108 struct rbd_obj_request *obj_request)
1110 rbd_assert(obj_request->which != BAD_WHICH);
1112 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1113 obj_request->which);
1114 list_del(&obj_request->links);
1115 rbd_assert(img_request->obj_request_count > 0);
1116 img_request->obj_request_count--;
1117 rbd_assert(obj_request->which == img_request->obj_request_count);
1118 obj_request->which = BAD_WHICH;
1119 rbd_assert(obj_request->img_request == img_request);
1120 obj_request->img_request = NULL;
1121 obj_request->callback = NULL;
1122 rbd_obj_request_put(obj_request);
1125 static bool obj_request_type_valid(enum obj_request_type type)
1128 case OBJ_REQUEST_NODATA:
1129 case OBJ_REQUEST_BIO:
1130 case OBJ_REQUEST_PAGES:
1137 static int rbd_obj_request_submit(struct ceph_osd_client *osdc,
1138 struct rbd_obj_request *obj_request)
1140 dout("%s: osdc %p obj %p\n", __func__, osdc, obj_request);
1142 return ceph_osdc_start_request(osdc, obj_request->osd_req, false);
1145 static void rbd_img_request_complete(struct rbd_img_request *img_request)
1147 dout("%s: img %p\n", __func__, img_request);
1148 if (img_request->callback)
1149 img_request->callback(img_request);
1151 rbd_img_request_put(img_request);
1154 /* Caller is responsible for rbd_obj_request_destroy(obj_request) */
1156 static int rbd_obj_request_wait(struct rbd_obj_request *obj_request)
1158 dout("%s: obj %p\n", __func__, obj_request);
1160 return wait_for_completion_interruptible(&obj_request->completion);
1163 static void obj_request_done_init(struct rbd_obj_request *obj_request)
1165 atomic_set(&obj_request->done, 0);
1169 static void obj_request_done_set(struct rbd_obj_request *obj_request)
1173 done = atomic_inc_return(&obj_request->done);
1175 struct rbd_img_request *img_request = obj_request->img_request;
1176 struct rbd_device *rbd_dev;
1178 rbd_dev = img_request ? img_request->rbd_dev : NULL;
1179 rbd_warn(rbd_dev, "obj_request %p was already done\n",
1184 static bool obj_request_done_test(struct rbd_obj_request *obj_request)
1187 return atomic_read(&obj_request->done) != 0;
1191 rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
1193 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1194 obj_request, obj_request->img_request, obj_request->result,
1195 obj_request->xferred, obj_request->length);
1197 * ENOENT means a hole in the image. We zero-fill the
1198 * entire length of the request. A short read also implies
1199 * zero-fill to the end of the request. Either way we
1200 * update the xferred count to indicate the whole request
1203 BUG_ON(obj_request->type != OBJ_REQUEST_BIO);
1204 if (obj_request->result == -ENOENT) {
1205 zero_bio_chain(obj_request->bio_list, 0);
1206 obj_request->result = 0;
1207 obj_request->xferred = obj_request->length;
1208 } else if (obj_request->xferred < obj_request->length &&
1209 !obj_request->result) {
1210 zero_bio_chain(obj_request->bio_list, obj_request->xferred);
1211 obj_request->xferred = obj_request->length;
1213 obj_request_done_set(obj_request);
1216 static void rbd_obj_request_complete(struct rbd_obj_request *obj_request)
1218 dout("%s: obj %p cb %p\n", __func__, obj_request,
1219 obj_request->callback);
1220 if (obj_request->callback)
1221 obj_request->callback(obj_request);
1223 complete_all(&obj_request->completion);
1226 static void rbd_osd_trivial_callback(struct rbd_obj_request *obj_request)
1228 dout("%s: obj %p\n", __func__, obj_request);
1229 obj_request_done_set(obj_request);
1232 static void rbd_osd_read_callback(struct rbd_obj_request *obj_request)
1234 dout("%s: obj %p result %d %llu/%llu\n", __func__, obj_request,
1235 obj_request->result, obj_request->xferred, obj_request->length);
1236 if (obj_request->img_request)
1237 rbd_img_obj_request_read_callback(obj_request);
1239 obj_request_done_set(obj_request);
1242 static void rbd_osd_write_callback(struct rbd_obj_request *obj_request)
1244 dout("%s: obj %p result %d %llu\n", __func__, obj_request,
1245 obj_request->result, obj_request->length);
1247 * There is no such thing as a successful short write.
1248 * Our xferred value is the number of bytes transferred
1249 * back. Set it to our originally-requested length.
1251 obj_request->xferred = obj_request->length;
1252 obj_request_done_set(obj_request);
1256 * For a simple stat call there's nothing to do. We'll do more if
1257 * this is part of a write sequence for a layered image.
1259 static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request)
1261 dout("%s: obj %p\n", __func__, obj_request);
1262 obj_request_done_set(obj_request);
1265 static void rbd_osd_req_callback(struct ceph_osd_request *osd_req,
1266 struct ceph_msg *msg)
1268 struct rbd_obj_request *obj_request = osd_req->r_priv;
1271 dout("%s: osd_req %p msg %p\n", __func__, osd_req, msg);
1272 rbd_assert(osd_req == obj_request->osd_req);
1273 rbd_assert(!!obj_request->img_request ^
1274 (obj_request->which == BAD_WHICH));
1276 if (osd_req->r_result < 0)
1277 obj_request->result = osd_req->r_result;
1278 obj_request->version = le64_to_cpu(osd_req->r_reassert_version.version);
1280 WARN_ON(osd_req->r_num_ops != 1); /* For now */
1283 * We support a 64-bit length, but ultimately it has to be
1284 * passed to blk_end_request(), which takes an unsigned int.
1286 obj_request->xferred = osd_req->r_reply_op_len[0];
1287 rbd_assert(obj_request->xferred < (u64) UINT_MAX);
1288 opcode = osd_req->r_ops[0].op;
1290 case CEPH_OSD_OP_READ:
1291 rbd_osd_read_callback(obj_request);
1293 case CEPH_OSD_OP_WRITE:
1294 rbd_osd_write_callback(obj_request);
1296 case CEPH_OSD_OP_STAT:
1297 rbd_osd_stat_callback(obj_request);
1299 case CEPH_OSD_OP_CALL:
1300 case CEPH_OSD_OP_NOTIFY_ACK:
1301 case CEPH_OSD_OP_WATCH:
1302 rbd_osd_trivial_callback(obj_request);
1305 rbd_warn(NULL, "%s: unsupported op %hu\n",
1306 obj_request->object_name, (unsigned short) opcode);
1310 if (obj_request_done_test(obj_request))
1311 rbd_obj_request_complete(obj_request);
1314 static void rbd_osd_req_format_op(struct rbd_obj_request *obj_request,
1317 struct rbd_img_request *img_request = obj_request->img_request;
1318 struct ceph_osd_request *osd_req = obj_request->osd_req;
1319 struct ceph_osd_data *osd_data = NULL;
1320 struct ceph_snap_context *snapc = NULL;
1321 u64 snap_id = CEPH_NOSNAP;
1322 struct timespec *mtime = NULL;
1323 struct timespec now;
1325 rbd_assert(osd_req != NULL);
1327 if (write_request) {
1328 osd_data = &osd_req->r_data_out;
1332 snapc = img_request->snapc;
1334 osd_data = &osd_req->r_data_in;
1336 snap_id = img_request->snap_id;
1338 if (obj_request->type != OBJ_REQUEST_NODATA) {
1339 struct ceph_osd_req_op *op = &obj_request->osd_req->r_ops[0];
1342 * If it has data, it's either a object class method
1343 * call (cls) or it's an extent operation.
1345 if (op->op == CEPH_OSD_OP_CALL)
1346 osd_req_op_cls_response_data(op, osd_data);
1348 osd_req_op_extent_osd_data(op, osd_data);
1350 ceph_osdc_build_request(osd_req, obj_request->offset,
1351 snapc, snap_id, mtime);
1354 static struct ceph_osd_request *rbd_osd_req_create(
1355 struct rbd_device *rbd_dev,
1357 struct rbd_obj_request *obj_request)
1359 struct rbd_img_request *img_request = obj_request->img_request;
1360 struct ceph_snap_context *snapc = NULL;
1361 struct ceph_osd_client *osdc;
1362 struct ceph_osd_request *osd_req;
1363 struct ceph_osd_data *osd_data;
1364 u64 offset = obj_request->offset;
1367 rbd_assert(img_request->write_request == write_request);
1368 if (img_request->write_request)
1369 snapc = img_request->snapc;
1372 /* Allocate and initialize the request, for the single op */
1374 osdc = &rbd_dev->rbd_client->client->osdc;
1375 osd_req = ceph_osdc_alloc_request(osdc, snapc, 1, false, GFP_ATOMIC);
1377 return NULL; /* ENOMEM */
1378 osd_data = write_request ? &osd_req->r_data_out : &osd_req->r_data_in;
1380 rbd_assert(obj_request_type_valid(obj_request->type));
1381 switch (obj_request->type) {
1382 case OBJ_REQUEST_NODATA:
1383 break; /* Nothing to do */
1384 case OBJ_REQUEST_BIO:
1385 rbd_assert(obj_request->bio_list != NULL);
1386 ceph_osd_data_bio_init(osd_data, obj_request->bio_list,
1387 obj_request->length);
1389 case OBJ_REQUEST_PAGES:
1390 ceph_osd_data_pages_init(osd_data, obj_request->pages,
1391 obj_request->length, offset & ~PAGE_MASK,
1397 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1399 osd_req->r_flags = CEPH_OSD_FLAG_READ;
1401 osd_req->r_callback = rbd_osd_req_callback;
1402 osd_req->r_priv = obj_request;
1404 osd_req->r_oid_len = strlen(obj_request->object_name);
1405 rbd_assert(osd_req->r_oid_len < sizeof (osd_req->r_oid));
1406 memcpy(osd_req->r_oid, obj_request->object_name, osd_req->r_oid_len);
1408 osd_req->r_file_layout = rbd_dev->layout; /* struct */
1413 static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req)
1415 ceph_osdc_put_request(osd_req);
1418 /* object_name is assumed to be a non-null pointer and NUL-terminated */
1420 static struct rbd_obj_request *rbd_obj_request_create(const char *object_name,
1421 u64 offset, u64 length,
1422 enum obj_request_type type)
1424 struct rbd_obj_request *obj_request;
1428 rbd_assert(obj_request_type_valid(type));
1430 size = strlen(object_name) + 1;
1431 obj_request = kzalloc(sizeof (*obj_request) + size, GFP_KERNEL);
1435 name = (char *)(obj_request + 1);
1436 obj_request->object_name = memcpy(name, object_name, size);
1437 obj_request->offset = offset;
1438 obj_request->length = length;
1439 obj_request->which = BAD_WHICH;
1440 obj_request->type = type;
1441 INIT_LIST_HEAD(&obj_request->links);
1442 obj_request_done_init(obj_request);
1443 init_completion(&obj_request->completion);
1444 kref_init(&obj_request->kref);
1446 dout("%s: \"%s\" %llu/%llu %d -> obj %p\n", __func__, object_name,
1447 offset, length, (int)type, obj_request);
1452 static void rbd_obj_request_destroy(struct kref *kref)
1454 struct rbd_obj_request *obj_request;
1456 obj_request = container_of(kref, struct rbd_obj_request, kref);
1458 dout("%s: obj %p\n", __func__, obj_request);
1460 rbd_assert(obj_request->img_request == NULL);
1461 rbd_assert(obj_request->which == BAD_WHICH);
1463 if (obj_request->osd_req)
1464 rbd_osd_req_destroy(obj_request->osd_req);
1466 rbd_assert(obj_request_type_valid(obj_request->type));
1467 switch (obj_request->type) {
1468 case OBJ_REQUEST_NODATA:
1469 break; /* Nothing to do */
1470 case OBJ_REQUEST_BIO:
1471 if (obj_request->bio_list)
1472 bio_chain_put(obj_request->bio_list);
1474 case OBJ_REQUEST_PAGES:
1475 if (obj_request->pages)
1476 ceph_release_page_vector(obj_request->pages,
1477 obj_request->page_count);
1485 * Caller is responsible for filling in the list of object requests
1486 * that comprises the image request, and the Linux request pointer
1487 * (if there is one).
1489 static struct rbd_img_request *rbd_img_request_create(
1490 struct rbd_device *rbd_dev,
1491 u64 offset, u64 length,
1494 struct rbd_img_request *img_request;
1495 struct ceph_snap_context *snapc = NULL;
1497 img_request = kmalloc(sizeof (*img_request), GFP_ATOMIC);
1501 if (write_request) {
1502 down_read(&rbd_dev->header_rwsem);
1503 snapc = ceph_get_snap_context(rbd_dev->header.snapc);
1504 up_read(&rbd_dev->header_rwsem);
1505 if (WARN_ON(!snapc)) {
1507 return NULL; /* Shouldn't happen */
1511 img_request->rq = NULL;
1512 img_request->rbd_dev = rbd_dev;
1513 img_request->offset = offset;
1514 img_request->length = length;
1515 img_request->write_request = write_request;
1517 img_request->snapc = snapc;
1519 img_request->snap_id = rbd_dev->spec->snap_id;
1520 spin_lock_init(&img_request->completion_lock);
1521 img_request->next_completion = 0;
1522 img_request->callback = NULL;
1523 img_request->obj_request_count = 0;
1524 INIT_LIST_HEAD(&img_request->obj_requests);
1525 kref_init(&img_request->kref);
1527 rbd_img_request_get(img_request); /* Avoid a warning */
1528 rbd_img_request_put(img_request); /* TEMPORARY */
1530 dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev,
1531 write_request ? "write" : "read", offset, length,
1537 static void rbd_img_request_destroy(struct kref *kref)
1539 struct rbd_img_request *img_request;
1540 struct rbd_obj_request *obj_request;
1541 struct rbd_obj_request *next_obj_request;
1543 img_request = container_of(kref, struct rbd_img_request, kref);
1545 dout("%s: img %p\n", __func__, img_request);
1547 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
1548 rbd_img_obj_request_del(img_request, obj_request);
1549 rbd_assert(img_request->obj_request_count == 0);
1551 if (img_request->write_request)
1552 ceph_put_snap_context(img_request->snapc);
1557 static int rbd_img_request_fill_bio(struct rbd_img_request *img_request,
1558 struct bio *bio_list)
1560 struct rbd_device *rbd_dev = img_request->rbd_dev;
1561 struct rbd_obj_request *obj_request = NULL;
1562 struct rbd_obj_request *next_obj_request;
1563 bool write_request = img_request->write_request;
1564 unsigned int bio_offset;
1569 dout("%s: img %p bio %p\n", __func__, img_request, bio_list);
1571 opcode = write_request ? CEPH_OSD_OP_WRITE : CEPH_OSD_OP_READ;
1573 image_offset = img_request->offset;
1574 rbd_assert(image_offset == bio_list->bi_sector << SECTOR_SHIFT);
1575 resid = img_request->length;
1576 rbd_assert(resid > 0);
1578 const char *object_name;
1579 unsigned int clone_size;
1580 struct ceph_osd_req_op *op;
1584 object_name = rbd_segment_name(rbd_dev, image_offset);
1587 offset = rbd_segment_offset(rbd_dev, image_offset);
1588 length = rbd_segment_length(rbd_dev, image_offset, resid);
1589 obj_request = rbd_obj_request_create(object_name,
1592 kfree(object_name); /* object request has its own copy */
1596 rbd_assert(length <= (u64) UINT_MAX);
1597 clone_size = (unsigned int) length;
1598 obj_request->bio_list = bio_chain_clone_range(&bio_list,
1599 &bio_offset, clone_size,
1601 if (!obj_request->bio_list)
1604 obj_request->osd_req = rbd_osd_req_create(rbd_dev,
1605 write_request, obj_request);
1606 if (!obj_request->osd_req)
1609 op = &obj_request->osd_req->r_ops[0];
1610 osd_req_op_extent_init(op, opcode, offset, length, 0, 0);
1611 rbd_osd_req_format_op(obj_request, write_request);
1613 /* status and version are initially zero-filled */
1615 rbd_img_obj_request_add(img_request, obj_request);
1617 image_offset += length;
1624 rbd_obj_request_put(obj_request);
1626 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
1627 rbd_obj_request_put(obj_request);
1632 static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
1634 struct rbd_img_request *img_request;
1635 u32 which = obj_request->which;
1638 img_request = obj_request->img_request;
1640 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
1641 rbd_assert(img_request != NULL);
1642 rbd_assert(img_request->rq != NULL);
1643 rbd_assert(img_request->obj_request_count > 0);
1644 rbd_assert(which != BAD_WHICH);
1645 rbd_assert(which < img_request->obj_request_count);
1646 rbd_assert(which >= img_request->next_completion);
1648 spin_lock_irq(&img_request->completion_lock);
1649 if (which != img_request->next_completion)
1652 for_each_obj_request_from(img_request, obj_request) {
1653 unsigned int xferred;
1657 rbd_assert(which < img_request->obj_request_count);
1659 if (!obj_request_done_test(obj_request))
1662 rbd_assert(obj_request->xferred <= (u64) UINT_MAX);
1663 xferred = (unsigned int) obj_request->xferred;
1664 result = (int) obj_request->result;
1666 rbd_warn(NULL, "obj_request %s result %d xferred %u\n",
1667 img_request->write_request ? "write" : "read",
1670 more = blk_end_request(img_request->rq, result, xferred);
1674 rbd_assert(more ^ (which == img_request->obj_request_count));
1675 img_request->next_completion = which;
1677 spin_unlock_irq(&img_request->completion_lock);
1680 rbd_img_request_complete(img_request);
1683 static int rbd_img_request_submit(struct rbd_img_request *img_request)
1685 struct rbd_device *rbd_dev = img_request->rbd_dev;
1686 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1687 struct rbd_obj_request *obj_request;
1688 struct rbd_obj_request *next_obj_request;
1690 dout("%s: img %p\n", __func__, img_request);
1691 for_each_obj_request_safe(img_request, obj_request, next_obj_request) {
1694 obj_request->callback = rbd_img_obj_callback;
1695 ret = rbd_obj_request_submit(osdc, obj_request);
1699 * The image request has its own reference to each
1700 * of its object requests, so we can safely drop the
1703 rbd_obj_request_put(obj_request);
1709 static int rbd_obj_notify_ack(struct rbd_device *rbd_dev,
1710 u64 ver, u64 notify_id)
1712 struct rbd_obj_request *obj_request;
1713 struct ceph_osd_req_op *op;
1714 struct ceph_osd_client *osdc;
1717 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
1718 OBJ_REQUEST_NODATA);
1723 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
1724 if (!obj_request->osd_req)
1727 op = &obj_request->osd_req->r_ops[0];
1728 osd_req_op_watch_init(op, CEPH_OSD_OP_NOTIFY_ACK, notify_id, ver, 0);
1729 rbd_osd_req_format_op(obj_request, false);
1731 osdc = &rbd_dev->rbd_client->client->osdc;
1732 obj_request->callback = rbd_obj_request_put;
1733 ret = rbd_obj_request_submit(osdc, obj_request);
1736 rbd_obj_request_put(obj_request);
1741 static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
1743 struct rbd_device *rbd_dev = (struct rbd_device *)data;
1750 dout("%s: \"%s\" notify_id %llu opcode %u\n", __func__,
1751 rbd_dev->header_name, (unsigned long long) notify_id,
1752 (unsigned int) opcode);
1753 rc = rbd_dev_refresh(rbd_dev, &hver);
1755 rbd_warn(rbd_dev, "got notification but failed to "
1756 " update snaps: %d\n", rc);
1758 rbd_obj_notify_ack(rbd_dev, hver, notify_id);
1762 * Request sync osd watch/unwatch. The value of "start" determines
1763 * whether a watch request is being initiated or torn down.
1765 static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, int start)
1767 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
1768 struct rbd_obj_request *obj_request;
1769 struct ceph_osd_req_op *op;
1772 rbd_assert(start ^ !!rbd_dev->watch_event);
1773 rbd_assert(start ^ !!rbd_dev->watch_request);
1776 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
1777 &rbd_dev->watch_event);
1780 rbd_assert(rbd_dev->watch_event != NULL);
1784 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
1785 OBJ_REQUEST_NODATA);
1789 obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, obj_request);
1790 if (!obj_request->osd_req)
1793 op = &obj_request->osd_req->r_ops[0];
1794 osd_req_op_watch_init(op, CEPH_OSD_OP_WATCH,
1795 rbd_dev->watch_event->cookie,
1796 rbd_dev->header.obj_version, start);
1797 rbd_osd_req_format_op(obj_request, true);
1800 ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
1802 ceph_osdc_unregister_linger_request(osdc,
1803 rbd_dev->watch_request->osd_req);
1804 ret = rbd_obj_request_submit(osdc, obj_request);
1807 ret = rbd_obj_request_wait(obj_request);
1810 ret = obj_request->result;
1815 * A watch request is set to linger, so the underlying osd
1816 * request won't go away until we unregister it. We retain
1817 * a pointer to the object request during that time (in
1818 * rbd_dev->watch_request), so we'll keep a reference to
1819 * it. We'll drop that reference (below) after we've
1823 rbd_dev->watch_request = obj_request;
1828 /* We have successfully torn down the watch request */
1830 rbd_obj_request_put(rbd_dev->watch_request);
1831 rbd_dev->watch_request = NULL;
1833 /* Cancel the event if we're tearing down, or on error */
1834 ceph_osdc_cancel_event(rbd_dev->watch_event);
1835 rbd_dev->watch_event = NULL;
1837 rbd_obj_request_put(obj_request);
1843 * Synchronous osd object method call
1845 static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
1846 const char *object_name,
1847 const char *class_name,
1848 const char *method_name,
1849 const char *outbound,
1850 size_t outbound_size,
1852 size_t inbound_size,
1855 struct rbd_obj_request *obj_request;
1856 struct ceph_osd_client *osdc;
1857 struct ceph_osd_req_op *op;
1858 struct page **pages;
1863 * Method calls are ultimately read operations. The result
1864 * should placed into the inbound buffer provided. They
1865 * also supply outbound data--parameters for the object
1866 * method. Currently if this is present it will be a
1869 page_count = (u32) calc_pages_for(0, inbound_size);
1870 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
1872 return PTR_ERR(pages);
1875 obj_request = rbd_obj_request_create(object_name, 0, inbound_size,
1880 obj_request->pages = pages;
1881 obj_request->page_count = page_count;
1883 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
1884 if (!obj_request->osd_req)
1887 op = &obj_request->osd_req->r_ops[0];
1888 osd_req_op_cls_init(op, CEPH_OSD_OP_CALL, class_name, method_name,
1889 outbound, outbound_size);
1890 rbd_osd_req_format_op(obj_request, false);
1892 osdc = &rbd_dev->rbd_client->client->osdc;
1893 ret = rbd_obj_request_submit(osdc, obj_request);
1896 ret = rbd_obj_request_wait(obj_request);
1900 ret = obj_request->result;
1904 ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred);
1906 *version = obj_request->version;
1909 rbd_obj_request_put(obj_request);
1911 ceph_release_page_vector(pages, page_count);
1916 static void rbd_request_fn(struct request_queue *q)
1917 __releases(q->queue_lock) __acquires(q->queue_lock)
1919 struct rbd_device *rbd_dev = q->queuedata;
1920 bool read_only = rbd_dev->mapping.read_only;
1924 while ((rq = blk_fetch_request(q))) {
1925 bool write_request = rq_data_dir(rq) == WRITE;
1926 struct rbd_img_request *img_request;
1930 /* Ignore any non-FS requests that filter through. */
1932 if (rq->cmd_type != REQ_TYPE_FS) {
1933 dout("%s: non-fs request type %d\n", __func__,
1934 (int) rq->cmd_type);
1935 __blk_end_request_all(rq, 0);
1939 /* Ignore/skip any zero-length requests */
1941 offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT;
1942 length = (u64) blk_rq_bytes(rq);
1945 dout("%s: zero-length request\n", __func__);
1946 __blk_end_request_all(rq, 0);
1950 spin_unlock_irq(q->queue_lock);
1952 /* Disallow writes to a read-only device */
1954 if (write_request) {
1958 rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP);
1962 * Quit early if the mapped snapshot no longer
1963 * exists. It's still possible the snapshot will
1964 * have disappeared by the time our request arrives
1965 * at the osd, but there's no sense in sending it if
1968 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) {
1969 dout("request for non-existent snapshot");
1970 rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP);
1976 if (WARN_ON(offset && length > U64_MAX - offset + 1))
1977 goto end_request; /* Shouldn't happen */
1980 img_request = rbd_img_request_create(rbd_dev, offset, length,
1985 img_request->rq = rq;
1987 result = rbd_img_request_fill_bio(img_request, rq->bio);
1989 result = rbd_img_request_submit(img_request);
1991 rbd_img_request_put(img_request);
1993 spin_lock_irq(q->queue_lock);
1995 rbd_warn(rbd_dev, "obj_request %s result %d\n",
1996 write_request ? "write" : "read", result);
1997 __blk_end_request_all(rq, result);
2003 * a queue callback. Makes sure that we don't create a bio that spans across
2004 * multiple osd objects. One exception would be with a single page bios,
2005 * which we handle later at bio_chain_clone_range()
2007 static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2008 struct bio_vec *bvec)
2010 struct rbd_device *rbd_dev = q->queuedata;
2011 sector_t sector_offset;
2012 sector_t sectors_per_obj;
2013 sector_t obj_sector_offset;
2017 * Find how far into its rbd object the partition-relative
2018 * bio start sector is to offset relative to the enclosing
2021 sector_offset = get_start_sect(bmd->bi_bdev) + bmd->bi_sector;
2022 sectors_per_obj = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT);
2023 obj_sector_offset = sector_offset & (sectors_per_obj - 1);
2026 * Compute the number of bytes from that offset to the end
2027 * of the object. Account for what's already used by the bio.
2029 ret = (int) (sectors_per_obj - obj_sector_offset) << SECTOR_SHIFT;
2030 if (ret > bmd->bi_size)
2031 ret -= bmd->bi_size;
2036 * Don't send back more than was asked for. And if the bio
2037 * was empty, let the whole thing through because: "Note
2038 * that a block device *must* allow a single page to be
2039 * added to an empty bio."
2041 rbd_assert(bvec->bv_len <= PAGE_SIZE);
2042 if (ret > (int) bvec->bv_len || !bmd->bi_size)
2043 ret = (int) bvec->bv_len;
2048 static void rbd_free_disk(struct rbd_device *rbd_dev)
2050 struct gendisk *disk = rbd_dev->disk;
2055 if (disk->flags & GENHD_FL_UP)
2058 blk_cleanup_queue(disk->queue);
2062 static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
2063 const char *object_name,
2064 u64 offset, u64 length,
2065 char *buf, u64 *version)
2068 struct rbd_obj_request *obj_request;
2069 struct ceph_osd_req_op *op;
2070 struct ceph_osd_client *osdc;
2071 struct page **pages = NULL;
2076 page_count = (u32) calc_pages_for(offset, length);
2077 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2079 ret = PTR_ERR(pages);
2082 obj_request = rbd_obj_request_create(object_name, offset, length,
2087 obj_request->pages = pages;
2088 obj_request->page_count = page_count;
2090 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
2091 if (!obj_request->osd_req)
2094 op = &obj_request->osd_req->r_ops[0];
2095 osd_req_op_extent_init(op, CEPH_OSD_OP_READ, offset, length, 0, 0);
2096 rbd_osd_req_format_op(obj_request, false);
2098 osdc = &rbd_dev->rbd_client->client->osdc;
2099 ret = rbd_obj_request_submit(osdc, obj_request);
2102 ret = rbd_obj_request_wait(obj_request);
2106 ret = obj_request->result;
2110 rbd_assert(obj_request->xferred <= (u64) SIZE_MAX);
2111 size = (size_t) obj_request->xferred;
2112 ceph_copy_from_page_vector(pages, buf, 0, size);
2113 rbd_assert(size <= (size_t) INT_MAX);
2116 *version = obj_request->version;
2119 rbd_obj_request_put(obj_request);
2121 ceph_release_page_vector(pages, page_count);
2127 * Read the complete header for the given rbd device.
2129 * Returns a pointer to a dynamically-allocated buffer containing
2130 * the complete and validated header. Caller can pass the address
2131 * of a variable that will be filled in with the version of the
2132 * header object at the time it was read.
2134 * Returns a pointer-coded errno if a failure occurs.
2136 static struct rbd_image_header_ondisk *
2137 rbd_dev_v1_header_read(struct rbd_device *rbd_dev, u64 *version)
2139 struct rbd_image_header_ondisk *ondisk = NULL;
2146 * The complete header will include an array of its 64-bit
2147 * snapshot ids, followed by the names of those snapshots as
2148 * a contiguous block of NUL-terminated strings. Note that
2149 * the number of snapshots could change by the time we read
2150 * it in, in which case we re-read it.
2157 size = sizeof (*ondisk);
2158 size += snap_count * sizeof (struct rbd_image_snap_ondisk);
2160 ondisk = kmalloc(size, GFP_KERNEL);
2162 return ERR_PTR(-ENOMEM);
2164 ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name,
2166 (char *) ondisk, version);
2169 if (WARN_ON((size_t) ret < size)) {
2171 rbd_warn(rbd_dev, "short header read (want %zd got %d)",
2175 if (!rbd_dev_ondisk_valid(ondisk)) {
2177 rbd_warn(rbd_dev, "invalid header");
2181 names_size = le64_to_cpu(ondisk->snap_names_len);
2182 want_count = snap_count;
2183 snap_count = le32_to_cpu(ondisk->snap_count);
2184 } while (snap_count != want_count);
2191 return ERR_PTR(ret);
2195 * reload the ondisk the header
2197 static int rbd_read_header(struct rbd_device *rbd_dev,
2198 struct rbd_image_header *header)
2200 struct rbd_image_header_ondisk *ondisk;
2204 ondisk = rbd_dev_v1_header_read(rbd_dev, &ver);
2206 return PTR_ERR(ondisk);
2207 ret = rbd_header_from_disk(header, ondisk);
2209 header->obj_version = ver;
2215 static void rbd_remove_all_snaps(struct rbd_device *rbd_dev)
2217 struct rbd_snap *snap;
2218 struct rbd_snap *next;
2220 list_for_each_entry_safe(snap, next, &rbd_dev->snaps, node)
2221 rbd_remove_snap_dev(snap);
2224 static void rbd_update_mapping_size(struct rbd_device *rbd_dev)
2228 if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
2231 size = (sector_t) rbd_dev->header.image_size / SECTOR_SIZE;
2232 dout("setting size to %llu sectors", (unsigned long long) size);
2233 rbd_dev->mapping.size = (u64) size;
2234 set_capacity(rbd_dev->disk, size);
2238 * only read the first part of the ondisk header, without the snaps info
2240 static int rbd_dev_v1_refresh(struct rbd_device *rbd_dev, u64 *hver)
2243 struct rbd_image_header h;
2245 ret = rbd_read_header(rbd_dev, &h);
2249 down_write(&rbd_dev->header_rwsem);
2251 /* Update image size, and check for resize of mapped image */
2252 rbd_dev->header.image_size = h.image_size;
2253 rbd_update_mapping_size(rbd_dev);
2255 /* rbd_dev->header.object_prefix shouldn't change */
2256 kfree(rbd_dev->header.snap_sizes);
2257 kfree(rbd_dev->header.snap_names);
2258 /* osd requests may still refer to snapc */
2259 ceph_put_snap_context(rbd_dev->header.snapc);
2262 *hver = h.obj_version;
2263 rbd_dev->header.obj_version = h.obj_version;
2264 rbd_dev->header.image_size = h.image_size;
2265 rbd_dev->header.snapc = h.snapc;
2266 rbd_dev->header.snap_names = h.snap_names;
2267 rbd_dev->header.snap_sizes = h.snap_sizes;
2268 /* Free the extra copy of the object prefix */
2269 WARN_ON(strcmp(rbd_dev->header.object_prefix, h.object_prefix));
2270 kfree(h.object_prefix);
2272 ret = rbd_dev_snaps_update(rbd_dev);
2274 ret = rbd_dev_snaps_register(rbd_dev);
2276 up_write(&rbd_dev->header_rwsem);
2281 static int rbd_dev_refresh(struct rbd_device *rbd_dev, u64 *hver)
2285 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
2286 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2287 if (rbd_dev->image_format == 1)
2288 ret = rbd_dev_v1_refresh(rbd_dev, hver);
2290 ret = rbd_dev_v2_refresh(rbd_dev, hver);
2291 mutex_unlock(&ctl_mutex);
2296 static int rbd_init_disk(struct rbd_device *rbd_dev)
2298 struct gendisk *disk;
2299 struct request_queue *q;
2302 /* create gendisk info */
2303 disk = alloc_disk(RBD_MINORS_PER_MAJOR);
2307 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
2309 disk->major = rbd_dev->major;
2310 disk->first_minor = 0;
2311 disk->fops = &rbd_bd_ops;
2312 disk->private_data = rbd_dev;
2314 q = blk_init_queue(rbd_request_fn, &rbd_dev->lock);
2318 /* We use the default size, but let's be explicit about it. */
2319 blk_queue_physical_block_size(q, SECTOR_SIZE);
2321 /* set io sizes to object size */
2322 segment_size = rbd_obj_bytes(&rbd_dev->header);
2323 blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
2324 blk_queue_max_segment_size(q, segment_size);
2325 blk_queue_io_min(q, segment_size);
2326 blk_queue_io_opt(q, segment_size);
2328 blk_queue_merge_bvec(q, rbd_merge_bvec);
2331 q->queuedata = rbd_dev;
2333 rbd_dev->disk = disk;
2335 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
2348 static struct rbd_device *dev_to_rbd_dev(struct device *dev)
2350 return container_of(dev, struct rbd_device, dev);
2353 static ssize_t rbd_size_show(struct device *dev,
2354 struct device_attribute *attr, char *buf)
2356 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2359 down_read(&rbd_dev->header_rwsem);
2360 size = get_capacity(rbd_dev->disk);
2361 up_read(&rbd_dev->header_rwsem);
2363 return sprintf(buf, "%llu\n", (unsigned long long) size * SECTOR_SIZE);
2367 * Note this shows the features for whatever's mapped, which is not
2368 * necessarily the base image.
2370 static ssize_t rbd_features_show(struct device *dev,
2371 struct device_attribute *attr, char *buf)
2373 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2375 return sprintf(buf, "0x%016llx\n",
2376 (unsigned long long) rbd_dev->mapping.features);
2379 static ssize_t rbd_major_show(struct device *dev,
2380 struct device_attribute *attr, char *buf)
2382 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2384 return sprintf(buf, "%d\n", rbd_dev->major);
2387 static ssize_t rbd_client_id_show(struct device *dev,
2388 struct device_attribute *attr, char *buf)
2390 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2392 return sprintf(buf, "client%lld\n",
2393 ceph_client_id(rbd_dev->rbd_client->client));
2396 static ssize_t rbd_pool_show(struct device *dev,
2397 struct device_attribute *attr, char *buf)
2399 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2401 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
2404 static ssize_t rbd_pool_id_show(struct device *dev,
2405 struct device_attribute *attr, char *buf)
2407 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2409 return sprintf(buf, "%llu\n",
2410 (unsigned long long) rbd_dev->spec->pool_id);
2413 static ssize_t rbd_name_show(struct device *dev,
2414 struct device_attribute *attr, char *buf)
2416 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2418 if (rbd_dev->spec->image_name)
2419 return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
2421 return sprintf(buf, "(unknown)\n");
2424 static ssize_t rbd_image_id_show(struct device *dev,
2425 struct device_attribute *attr, char *buf)
2427 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2429 return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
2433 * Shows the name of the currently-mapped snapshot (or
2434 * RBD_SNAP_HEAD_NAME for the base image).
2436 static ssize_t rbd_snap_show(struct device *dev,
2437 struct device_attribute *attr,
2440 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2442 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
2446 * For an rbd v2 image, shows the pool id, image id, and snapshot id
2447 * for the parent image. If there is no parent, simply shows
2448 * "(no parent image)".
2450 static ssize_t rbd_parent_show(struct device *dev,
2451 struct device_attribute *attr,
2454 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2455 struct rbd_spec *spec = rbd_dev->parent_spec;
2460 return sprintf(buf, "(no parent image)\n");
2462 count = sprintf(bufp, "pool_id %llu\npool_name %s\n",
2463 (unsigned long long) spec->pool_id, spec->pool_name);
2468 count = sprintf(bufp, "image_id %s\nimage_name %s\n", spec->image_id,
2469 spec->image_name ? spec->image_name : "(unknown)");
2474 count = sprintf(bufp, "snap_id %llu\nsnap_name %s\n",
2475 (unsigned long long) spec->snap_id, spec->snap_name);
2480 count = sprintf(bufp, "overlap %llu\n", rbd_dev->parent_overlap);
2485 return (ssize_t) (bufp - buf);
2488 static ssize_t rbd_image_refresh(struct device *dev,
2489 struct device_attribute *attr,
2493 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
2496 ret = rbd_dev_refresh(rbd_dev, NULL);
2498 return ret < 0 ? ret : size;
2501 static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
2502 static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL);
2503 static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
2504 static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
2505 static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
2506 static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL);
2507 static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
2508 static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL);
2509 static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
2510 static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
2511 static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL);
2513 static struct attribute *rbd_attrs[] = {
2514 &dev_attr_size.attr,
2515 &dev_attr_features.attr,
2516 &dev_attr_major.attr,
2517 &dev_attr_client_id.attr,
2518 &dev_attr_pool.attr,
2519 &dev_attr_pool_id.attr,
2520 &dev_attr_name.attr,
2521 &dev_attr_image_id.attr,
2522 &dev_attr_current_snap.attr,
2523 &dev_attr_parent.attr,
2524 &dev_attr_refresh.attr,
2528 static struct attribute_group rbd_attr_group = {
2532 static const struct attribute_group *rbd_attr_groups[] = {
2537 static void rbd_sysfs_dev_release(struct device *dev)
2541 static struct device_type rbd_device_type = {
2543 .groups = rbd_attr_groups,
2544 .release = rbd_sysfs_dev_release,
2552 static ssize_t rbd_snap_size_show(struct device *dev,
2553 struct device_attribute *attr,
2556 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
2558 return sprintf(buf, "%llu\n", (unsigned long long)snap->size);
2561 static ssize_t rbd_snap_id_show(struct device *dev,
2562 struct device_attribute *attr,
2565 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
2567 return sprintf(buf, "%llu\n", (unsigned long long)snap->id);
2570 static ssize_t rbd_snap_features_show(struct device *dev,
2571 struct device_attribute *attr,
2574 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
2576 return sprintf(buf, "0x%016llx\n",
2577 (unsigned long long) snap->features);
2580 static DEVICE_ATTR(snap_size, S_IRUGO, rbd_snap_size_show, NULL);
2581 static DEVICE_ATTR(snap_id, S_IRUGO, rbd_snap_id_show, NULL);
2582 static DEVICE_ATTR(snap_features, S_IRUGO, rbd_snap_features_show, NULL);
2584 static struct attribute *rbd_snap_attrs[] = {
2585 &dev_attr_snap_size.attr,
2586 &dev_attr_snap_id.attr,
2587 &dev_attr_snap_features.attr,
2591 static struct attribute_group rbd_snap_attr_group = {
2592 .attrs = rbd_snap_attrs,
2595 static void rbd_snap_dev_release(struct device *dev)
2597 struct rbd_snap *snap = container_of(dev, struct rbd_snap, dev);
2602 static const struct attribute_group *rbd_snap_attr_groups[] = {
2603 &rbd_snap_attr_group,
2607 static struct device_type rbd_snap_device_type = {
2608 .groups = rbd_snap_attr_groups,
2609 .release = rbd_snap_dev_release,
2612 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
2614 kref_get(&spec->kref);
2619 static void rbd_spec_free(struct kref *kref);
2620 static void rbd_spec_put(struct rbd_spec *spec)
2623 kref_put(&spec->kref, rbd_spec_free);
2626 static struct rbd_spec *rbd_spec_alloc(void)
2628 struct rbd_spec *spec;
2630 spec = kzalloc(sizeof (*spec), GFP_KERNEL);
2633 kref_init(&spec->kref);
2635 rbd_spec_put(rbd_spec_get(spec)); /* TEMPORARY */
2640 static void rbd_spec_free(struct kref *kref)
2642 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
2644 kfree(spec->pool_name);
2645 kfree(spec->image_id);
2646 kfree(spec->image_name);
2647 kfree(spec->snap_name);
2651 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
2652 struct rbd_spec *spec)
2654 struct rbd_device *rbd_dev;
2656 rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL);
2660 spin_lock_init(&rbd_dev->lock);
2662 INIT_LIST_HEAD(&rbd_dev->node);
2663 INIT_LIST_HEAD(&rbd_dev->snaps);
2664 init_rwsem(&rbd_dev->header_rwsem);
2666 rbd_dev->spec = spec;
2667 rbd_dev->rbd_client = rbdc;
2669 /* Initialize the layout used for all rbd requests */
2671 rbd_dev->layout.fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
2672 rbd_dev->layout.fl_stripe_count = cpu_to_le32(1);
2673 rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
2674 rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id);
2679 static void rbd_dev_destroy(struct rbd_device *rbd_dev)
2681 rbd_spec_put(rbd_dev->parent_spec);
2682 kfree(rbd_dev->header_name);
2683 rbd_put_client(rbd_dev->rbd_client);
2684 rbd_spec_put(rbd_dev->spec);
2688 static bool rbd_snap_registered(struct rbd_snap *snap)
2690 bool ret = snap->dev.type == &rbd_snap_device_type;
2691 bool reg = device_is_registered(&snap->dev);
2693 rbd_assert(!ret ^ reg);
2698 static void rbd_remove_snap_dev(struct rbd_snap *snap)
2700 list_del(&snap->node);
2701 if (device_is_registered(&snap->dev))
2702 device_unregister(&snap->dev);
2705 static int rbd_register_snap_dev(struct rbd_snap *snap,
2706 struct device *parent)
2708 struct device *dev = &snap->dev;
2711 dev->type = &rbd_snap_device_type;
2712 dev->parent = parent;
2713 dev->release = rbd_snap_dev_release;
2714 dev_set_name(dev, "%s%s", RBD_SNAP_DEV_NAME_PREFIX, snap->name);
2715 dout("%s: registering device for snapshot %s\n", __func__, snap->name);
2717 ret = device_register(dev);
2722 static struct rbd_snap *__rbd_add_snap_dev(struct rbd_device *rbd_dev,
2723 const char *snap_name,
2724 u64 snap_id, u64 snap_size,
2727 struct rbd_snap *snap;
2730 snap = kzalloc(sizeof (*snap), GFP_KERNEL);
2732 return ERR_PTR(-ENOMEM);
2735 snap->name = kstrdup(snap_name, GFP_KERNEL);
2740 snap->size = snap_size;
2741 snap->features = snap_features;
2749 return ERR_PTR(ret);
2752 static char *rbd_dev_v1_snap_info(struct rbd_device *rbd_dev, u32 which,
2753 u64 *snap_size, u64 *snap_features)
2757 rbd_assert(which < rbd_dev->header.snapc->num_snaps);
2759 *snap_size = rbd_dev->header.snap_sizes[which];
2760 *snap_features = 0; /* No features for v1 */
2762 /* Skip over names until we find the one we are looking for */
2764 snap_name = rbd_dev->header.snap_names;
2766 snap_name += strlen(snap_name) + 1;
2772 * Get the size and object order for an image snapshot, or if
2773 * snap_id is CEPH_NOSNAP, gets this information for the base
2776 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
2777 u8 *order, u64 *snap_size)
2779 __le64 snapid = cpu_to_le64(snap_id);
2784 } __attribute__ ((packed)) size_buf = { 0 };
2786 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
2788 (char *) &snapid, sizeof (snapid),
2789 (char *) &size_buf, sizeof (size_buf), NULL);
2790 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
2794 *order = size_buf.order;
2795 *snap_size = le64_to_cpu(size_buf.size);
2797 dout(" snap_id 0x%016llx order = %u, snap_size = %llu\n",
2798 (unsigned long long) snap_id, (unsigned int) *order,
2799 (unsigned long long) *snap_size);
2804 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
2806 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
2807 &rbd_dev->header.obj_order,
2808 &rbd_dev->header.image_size);
2811 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
2817 reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL);
2821 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
2822 "rbd", "get_object_prefix",
2824 reply_buf, RBD_OBJ_PREFIX_LEN_MAX, NULL);
2825 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
2830 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
2831 p + RBD_OBJ_PREFIX_LEN_MAX,
2834 if (IS_ERR(rbd_dev->header.object_prefix)) {
2835 ret = PTR_ERR(rbd_dev->header.object_prefix);
2836 rbd_dev->header.object_prefix = NULL;
2838 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix);
2847 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
2850 __le64 snapid = cpu_to_le64(snap_id);
2854 } features_buf = { 0 };
2858 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
2859 "rbd", "get_features",
2860 (char *) &snapid, sizeof (snapid),
2861 (char *) &features_buf, sizeof (features_buf),
2863 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
2867 incompat = le64_to_cpu(features_buf.incompat);
2868 if (incompat & ~RBD_FEATURES_ALL)
2871 *snap_features = le64_to_cpu(features_buf.features);
2873 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
2874 (unsigned long long) snap_id,
2875 (unsigned long long) *snap_features,
2876 (unsigned long long) le64_to_cpu(features_buf.incompat));
2881 static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
2883 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
2884 &rbd_dev->header.features);
2887 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
2889 struct rbd_spec *parent_spec;
2891 void *reply_buf = NULL;
2899 parent_spec = rbd_spec_alloc();
2903 size = sizeof (__le64) + /* pool_id */
2904 sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */
2905 sizeof (__le64) + /* snap_id */
2906 sizeof (__le64); /* overlap */
2907 reply_buf = kmalloc(size, GFP_KERNEL);
2913 snapid = cpu_to_le64(CEPH_NOSNAP);
2914 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
2915 "rbd", "get_parent",
2916 (char *) &snapid, sizeof (snapid),
2917 (char *) reply_buf, size, NULL);
2918 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
2924 end = (char *) reply_buf + size;
2925 ceph_decode_64_safe(&p, end, parent_spec->pool_id, out_err);
2926 if (parent_spec->pool_id == CEPH_NOPOOL)
2927 goto out; /* No parent? No problem. */
2929 /* The ceph file layout needs to fit pool id in 32 bits */
2932 if (WARN_ON(parent_spec->pool_id > (u64) U32_MAX))
2935 image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
2936 if (IS_ERR(image_id)) {
2937 ret = PTR_ERR(image_id);
2940 parent_spec->image_id = image_id;
2941 ceph_decode_64_safe(&p, end, parent_spec->snap_id, out_err);
2942 ceph_decode_64_safe(&p, end, overlap, out_err);
2944 rbd_dev->parent_overlap = overlap;
2945 rbd_dev->parent_spec = parent_spec;
2946 parent_spec = NULL; /* rbd_dev now owns this */
2951 rbd_spec_put(parent_spec);
2956 static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
2958 size_t image_id_size;
2963 void *reply_buf = NULL;
2965 char *image_name = NULL;
2968 rbd_assert(!rbd_dev->spec->image_name);
2970 len = strlen(rbd_dev->spec->image_id);
2971 image_id_size = sizeof (__le32) + len;
2972 image_id = kmalloc(image_id_size, GFP_KERNEL);
2977 end = (char *) image_id + image_id_size;
2978 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32) len);
2980 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
2981 reply_buf = kmalloc(size, GFP_KERNEL);
2985 ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY,
2986 "rbd", "dir_get_name",
2987 image_id, image_id_size,
2988 (char *) reply_buf, size, NULL);
2992 end = (char *) reply_buf + size;
2993 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
2994 if (IS_ERR(image_name))
2997 dout("%s: name is %s len is %zd\n", __func__, image_name, len);
3006 * When a parent image gets probed, we only have the pool, image,
3007 * and snapshot ids but not the names of any of them. This call
3008 * is made later to fill in those names. It has to be done after
3009 * rbd_dev_snaps_update() has completed because some of the
3010 * information (in particular, snapshot name) is not available
3013 static int rbd_dev_probe_update_spec(struct rbd_device *rbd_dev)
3015 struct ceph_osd_client *osdc;
3017 void *reply_buf = NULL;
3020 if (rbd_dev->spec->pool_name)
3021 return 0; /* Already have the names */
3023 /* Look up the pool name */
3025 osdc = &rbd_dev->rbd_client->client->osdc;
3026 name = ceph_pg_pool_name_by_id(osdc->osdmap, rbd_dev->spec->pool_id);
3028 rbd_warn(rbd_dev, "there is no pool with id %llu",
3029 rbd_dev->spec->pool_id); /* Really a BUG() */
3033 rbd_dev->spec->pool_name = kstrdup(name, GFP_KERNEL);
3034 if (!rbd_dev->spec->pool_name)
3037 /* Fetch the image name; tolerate failure here */
3039 name = rbd_dev_image_name(rbd_dev);
3041 rbd_dev->spec->image_name = (char *) name;
3043 rbd_warn(rbd_dev, "unable to get image name");
3045 /* Look up the snapshot name. */
3047 name = rbd_snap_name(rbd_dev, rbd_dev->spec->snap_id);
3049 rbd_warn(rbd_dev, "no snapshot with id %llu",
3050 rbd_dev->spec->snap_id); /* Really a BUG() */
3054 rbd_dev->spec->snap_name = kstrdup(name, GFP_KERNEL);
3055 if(!rbd_dev->spec->snap_name)
3061 kfree(rbd_dev->spec->pool_name);
3062 rbd_dev->spec->pool_name = NULL;
3067 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev, u64 *ver)
3076 struct ceph_snap_context *snapc;
3080 * We'll need room for the seq value (maximum snapshot id),
3081 * snapshot count, and array of that many snapshot ids.
3082 * For now we have a fixed upper limit on the number we're
3083 * prepared to receive.
3085 size = sizeof (__le64) + sizeof (__le32) +
3086 RBD_MAX_SNAP_COUNT * sizeof (__le64);
3087 reply_buf = kzalloc(size, GFP_KERNEL);
3091 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3092 "rbd", "get_snapcontext",
3094 reply_buf, size, ver);
3095 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3101 end = (char *) reply_buf + size;
3102 ceph_decode_64_safe(&p, end, seq, out);
3103 ceph_decode_32_safe(&p, end, snap_count, out);
3106 * Make sure the reported number of snapshot ids wouldn't go
3107 * beyond the end of our buffer. But before checking that,
3108 * make sure the computed size of the snapshot context we
3109 * allocate is representable in a size_t.
3111 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
3116 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
3119 size = sizeof (struct ceph_snap_context) +
3120 snap_count * sizeof (snapc->snaps[0]);
3121 snapc = kmalloc(size, GFP_KERNEL);
3127 atomic_set(&snapc->nref, 1);
3129 snapc->num_snaps = snap_count;
3130 for (i = 0; i < snap_count; i++)
3131 snapc->snaps[i] = ceph_decode_64(&p);
3133 rbd_dev->header.snapc = snapc;
3135 dout(" snap context seq = %llu, snap_count = %u\n",
3136 (unsigned long long) seq, (unsigned int) snap_count);
3144 static char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, u32 which)
3154 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
3155 reply_buf = kmalloc(size, GFP_KERNEL);
3157 return ERR_PTR(-ENOMEM);
3159 snap_id = cpu_to_le64(rbd_dev->header.snapc->snaps[which]);
3160 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3161 "rbd", "get_snapshot_name",
3162 (char *) &snap_id, sizeof (snap_id),
3163 reply_buf, size, NULL);
3164 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3169 end = (char *) reply_buf + size;
3170 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
3171 if (IS_ERR(snap_name)) {
3172 ret = PTR_ERR(snap_name);
3175 dout(" snap_id 0x%016llx snap_name = %s\n",
3176 (unsigned long long) le64_to_cpu(snap_id), snap_name);
3184 return ERR_PTR(ret);
3187 static char *rbd_dev_v2_snap_info(struct rbd_device *rbd_dev, u32 which,
3188 u64 *snap_size, u64 *snap_features)
3194 snap_id = rbd_dev->header.snapc->snaps[which];
3195 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, &order, snap_size);
3197 return ERR_PTR(ret);
3198 ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, snap_features);
3200 return ERR_PTR(ret);
3202 return rbd_dev_v2_snap_name(rbd_dev, which);
3205 static char *rbd_dev_snap_info(struct rbd_device *rbd_dev, u32 which,
3206 u64 *snap_size, u64 *snap_features)
3208 if (rbd_dev->image_format == 1)
3209 return rbd_dev_v1_snap_info(rbd_dev, which,
3210 snap_size, snap_features);
3211 if (rbd_dev->image_format == 2)
3212 return rbd_dev_v2_snap_info(rbd_dev, which,
3213 snap_size, snap_features);
3214 return ERR_PTR(-EINVAL);
3217 static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev, u64 *hver)
3222 down_write(&rbd_dev->header_rwsem);
3224 /* Grab old order first, to see if it changes */
3226 obj_order = rbd_dev->header.obj_order,
3227 ret = rbd_dev_v2_image_size(rbd_dev);
3230 if (rbd_dev->header.obj_order != obj_order) {
3234 rbd_update_mapping_size(rbd_dev);
3236 ret = rbd_dev_v2_snap_context(rbd_dev, hver);
3237 dout("rbd_dev_v2_snap_context returned %d\n", ret);
3240 ret = rbd_dev_snaps_update(rbd_dev);
3241 dout("rbd_dev_snaps_update returned %d\n", ret);
3244 ret = rbd_dev_snaps_register(rbd_dev);
3245 dout("rbd_dev_snaps_register returned %d\n", ret);
3247 up_write(&rbd_dev->header_rwsem);
3253 * Scan the rbd device's current snapshot list and compare it to the
3254 * newly-received snapshot context. Remove any existing snapshots
3255 * not present in the new snapshot context. Add a new snapshot for
3256 * any snaphots in the snapshot context not in the current list.
3257 * And verify there are no changes to snapshots we already know
3260 * Assumes the snapshots in the snapshot context are sorted by
3261 * snapshot id, highest id first. (Snapshots in the rbd_dev's list
3262 * are also maintained in that order.)
3264 static int rbd_dev_snaps_update(struct rbd_device *rbd_dev)
3266 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
3267 const u32 snap_count = snapc->num_snaps;
3268 struct list_head *head = &rbd_dev->snaps;
3269 struct list_head *links = head->next;
3272 dout("%s: snap count is %u\n", __func__, (unsigned int) snap_count);
3273 while (index < snap_count || links != head) {
3275 struct rbd_snap *snap;
3278 u64 snap_features = 0;
3280 snap_id = index < snap_count ? snapc->snaps[index]
3282 snap = links != head ? list_entry(links, struct rbd_snap, node)
3284 rbd_assert(!snap || snap->id != CEPH_NOSNAP);
3286 if (snap_id == CEPH_NOSNAP || (snap && snap->id > snap_id)) {
3287 struct list_head *next = links->next;
3290 * A previously-existing snapshot is not in
3291 * the new snap context.
3293 * If the now missing snapshot is the one the
3294 * image is mapped to, clear its exists flag
3295 * so we can avoid sending any more requests
3298 if (rbd_dev->spec->snap_id == snap->id)
3299 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
3300 rbd_remove_snap_dev(snap);
3301 dout("%ssnap id %llu has been removed\n",
3302 rbd_dev->spec->snap_id == snap->id ?
3304 (unsigned long long) snap->id);
3306 /* Done with this list entry; advance */
3312 snap_name = rbd_dev_snap_info(rbd_dev, index,
3313 &snap_size, &snap_features);
3314 if (IS_ERR(snap_name))
3315 return PTR_ERR(snap_name);
3317 dout("entry %u: snap_id = %llu\n", (unsigned int) snap_count,
3318 (unsigned long long) snap_id);
3319 if (!snap || (snap_id != CEPH_NOSNAP && snap->id < snap_id)) {
3320 struct rbd_snap *new_snap;
3322 /* We haven't seen this snapshot before */
3324 new_snap = __rbd_add_snap_dev(rbd_dev, snap_name,
3325 snap_id, snap_size, snap_features);
3326 if (IS_ERR(new_snap)) {
3327 int err = PTR_ERR(new_snap);
3329 dout(" failed to add dev, error %d\n", err);
3334 /* New goes before existing, or at end of list */
3336 dout(" added dev%s\n", snap ? "" : " at end\n");
3338 list_add_tail(&new_snap->node, &snap->node);
3340 list_add_tail(&new_snap->node, head);
3342 /* Already have this one */
3344 dout(" already present\n");
3346 rbd_assert(snap->size == snap_size);
3347 rbd_assert(!strcmp(snap->name, snap_name));
3348 rbd_assert(snap->features == snap_features);
3350 /* Done with this list entry; advance */
3352 links = links->next;
3355 /* Advance to the next entry in the snapshot context */
3359 dout("%s: done\n", __func__);
3365 * Scan the list of snapshots and register the devices for any that
3366 * have not already been registered.
3368 static int rbd_dev_snaps_register(struct rbd_device *rbd_dev)
3370 struct rbd_snap *snap;
3373 dout("%s:\n", __func__);
3374 if (WARN_ON(!device_is_registered(&rbd_dev->dev)))
3377 list_for_each_entry(snap, &rbd_dev->snaps, node) {
3378 if (!rbd_snap_registered(snap)) {
3379 ret = rbd_register_snap_dev(snap, &rbd_dev->dev);
3384 dout("%s: returning %d\n", __func__, ret);
3389 static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
3394 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
3396 dev = &rbd_dev->dev;
3397 dev->bus = &rbd_bus_type;
3398 dev->type = &rbd_device_type;
3399 dev->parent = &rbd_root_dev;
3400 dev->release = rbd_dev_release;
3401 dev_set_name(dev, "%d", rbd_dev->dev_id);
3402 ret = device_register(dev);
3404 mutex_unlock(&ctl_mutex);
3409 static void rbd_bus_del_dev(struct rbd_device *rbd_dev)
3411 device_unregister(&rbd_dev->dev);
3414 static atomic64_t rbd_dev_id_max = ATOMIC64_INIT(0);
3417 * Get a unique rbd identifier for the given new rbd_dev, and add
3418 * the rbd_dev to the global list. The minimum rbd id is 1.
3420 static void rbd_dev_id_get(struct rbd_device *rbd_dev)
3422 rbd_dev->dev_id = atomic64_inc_return(&rbd_dev_id_max);
3424 spin_lock(&rbd_dev_list_lock);
3425 list_add_tail(&rbd_dev->node, &rbd_dev_list);
3426 spin_unlock(&rbd_dev_list_lock);
3427 dout("rbd_dev %p given dev id %llu\n", rbd_dev,
3428 (unsigned long long) rbd_dev->dev_id);
3432 * Remove an rbd_dev from the global list, and record that its
3433 * identifier is no longer in use.
3435 static void rbd_dev_id_put(struct rbd_device *rbd_dev)
3437 struct list_head *tmp;
3438 int rbd_id = rbd_dev->dev_id;
3441 rbd_assert(rbd_id > 0);
3443 dout("rbd_dev %p released dev id %llu\n", rbd_dev,
3444 (unsigned long long) rbd_dev->dev_id);
3445 spin_lock(&rbd_dev_list_lock);
3446 list_del_init(&rbd_dev->node);
3449 * If the id being "put" is not the current maximum, there
3450 * is nothing special we need to do.
3452 if (rbd_id != atomic64_read(&rbd_dev_id_max)) {
3453 spin_unlock(&rbd_dev_list_lock);
3458 * We need to update the current maximum id. Search the
3459 * list to find out what it is. We're more likely to find
3460 * the maximum at the end, so search the list backward.
3463 list_for_each_prev(tmp, &rbd_dev_list) {
3464 struct rbd_device *rbd_dev;
3466 rbd_dev = list_entry(tmp, struct rbd_device, node);
3467 if (rbd_dev->dev_id > max_id)
3468 max_id = rbd_dev->dev_id;
3470 spin_unlock(&rbd_dev_list_lock);
3473 * The max id could have been updated by rbd_dev_id_get(), in
3474 * which case it now accurately reflects the new maximum.
3475 * Be careful not to overwrite the maximum value in that
3478 atomic64_cmpxchg(&rbd_dev_id_max, rbd_id, max_id);
3479 dout(" max dev id has been reset\n");
3483 * Skips over white space at *buf, and updates *buf to point to the
3484 * first found non-space character (if any). Returns the length of
3485 * the token (string of non-white space characters) found. Note
3486 * that *buf must be terminated with '\0'.
3488 static inline size_t next_token(const char **buf)
3491 * These are the characters that produce nonzero for
3492 * isspace() in the "C" and "POSIX" locales.
3494 const char *spaces = " \f\n\r\t\v";
3496 *buf += strspn(*buf, spaces); /* Find start of token */
3498 return strcspn(*buf, spaces); /* Return token length */
3502 * Finds the next token in *buf, and if the provided token buffer is
3503 * big enough, copies the found token into it. The result, if
3504 * copied, is guaranteed to be terminated with '\0'. Note that *buf
3505 * must be terminated with '\0' on entry.
3507 * Returns the length of the token found (not including the '\0').
3508 * Return value will be 0 if no token is found, and it will be >=
3509 * token_size if the token would not fit.
3511 * The *buf pointer will be updated to point beyond the end of the
3512 * found token. Note that this occurs even if the token buffer is
3513 * too small to hold it.
3515 static inline size_t copy_token(const char **buf,
3521 len = next_token(buf);
3522 if (len < token_size) {
3523 memcpy(token, *buf, len);
3524 *(token + len) = '\0';
3532 * Finds the next token in *buf, dynamically allocates a buffer big
3533 * enough to hold a copy of it, and copies the token into the new
3534 * buffer. The copy is guaranteed to be terminated with '\0'. Note
3535 * that a duplicate buffer is created even for a zero-length token.
3537 * Returns a pointer to the newly-allocated duplicate, or a null
3538 * pointer if memory for the duplicate was not available. If
3539 * the lenp argument is a non-null pointer, the length of the token
3540 * (not including the '\0') is returned in *lenp.
3542 * If successful, the *buf pointer will be updated to point beyond
3543 * the end of the found token.
3545 * Note: uses GFP_KERNEL for allocation.
3547 static inline char *dup_token(const char **buf, size_t *lenp)
3552 len = next_token(buf);
3553 dup = kmemdup(*buf, len + 1, GFP_KERNEL);
3556 *(dup + len) = '\0';
3566 * Parse the options provided for an "rbd add" (i.e., rbd image
3567 * mapping) request. These arrive via a write to /sys/bus/rbd/add,
3568 * and the data written is passed here via a NUL-terminated buffer.
3569 * Returns 0 if successful or an error code otherwise.
3571 * The information extracted from these options is recorded in
3572 * the other parameters which return dynamically-allocated
3575 * The address of a pointer that will refer to a ceph options
3576 * structure. Caller must release the returned pointer using
3577 * ceph_destroy_options() when it is no longer needed.
3579 * Address of an rbd options pointer. Fully initialized by
3580 * this function; caller must release with kfree().
3582 * Address of an rbd image specification pointer. Fully
3583 * initialized by this function based on parsed options.
3584 * Caller must release with rbd_spec_put().
3586 * The options passed take this form:
3587 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
3590 * A comma-separated list of one or more monitor addresses.
3591 * A monitor address is an ip address, optionally followed
3592 * by a port number (separated by a colon).
3593 * I.e.: ip1[:port1][,ip2[:port2]...]
3595 * A comma-separated list of ceph and/or rbd options.
3597 * The name of the rados pool containing the rbd image.
3599 * The name of the image in that pool to map.
3601 * An optional snapshot id. If provided, the mapping will
3602 * present data from the image at the time that snapshot was
3603 * created. The image head is used if no snapshot id is
3604 * provided. Snapshot mappings are always read-only.
3606 static int rbd_add_parse_args(const char *buf,
3607 struct ceph_options **ceph_opts,
3608 struct rbd_options **opts,
3609 struct rbd_spec **rbd_spec)
3613 const char *mon_addrs;
3614 size_t mon_addrs_size;
3615 struct rbd_spec *spec = NULL;
3616 struct rbd_options *rbd_opts = NULL;
3617 struct ceph_options *copts;
3620 /* The first four tokens are required */
3622 len = next_token(&buf);
3624 rbd_warn(NULL, "no monitor address(es) provided");
3628 mon_addrs_size = len + 1;
3632 options = dup_token(&buf, NULL);
3636 rbd_warn(NULL, "no options provided");
3640 spec = rbd_spec_alloc();
3644 spec->pool_name = dup_token(&buf, NULL);
3645 if (!spec->pool_name)
3647 if (!*spec->pool_name) {
3648 rbd_warn(NULL, "no pool name provided");
3652 spec->image_name = dup_token(&buf, NULL);
3653 if (!spec->image_name)
3655 if (!*spec->image_name) {
3656 rbd_warn(NULL, "no image name provided");
3661 * Snapshot name is optional; default is to use "-"
3662 * (indicating the head/no snapshot).
3664 len = next_token(&buf);
3666 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
3667 len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
3668 } else if (len > RBD_MAX_SNAP_NAME_LEN) {
3669 ret = -ENAMETOOLONG;
3672 spec->snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
3673 if (!spec->snap_name)
3675 *(spec->snap_name + len) = '\0';
3677 /* Initialize all rbd options to the defaults */
3679 rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL);
3683 rbd_opts->read_only = RBD_READ_ONLY_DEFAULT;
3685 copts = ceph_parse_options(options, mon_addrs,
3686 mon_addrs + mon_addrs_size - 1,
3687 parse_rbd_opts_token, rbd_opts);
3688 if (IS_ERR(copts)) {
3689 ret = PTR_ERR(copts);
3710 * An rbd format 2 image has a unique identifier, distinct from the
3711 * name given to it by the user. Internally, that identifier is
3712 * what's used to specify the names of objects related to the image.
3714 * A special "rbd id" object is used to map an rbd image name to its
3715 * id. If that object doesn't exist, then there is no v2 rbd image
3716 * with the supplied name.
3718 * This function will record the given rbd_dev's image_id field if
3719 * it can be determined, and in that case will return 0. If any
3720 * errors occur a negative errno will be returned and the rbd_dev's
3721 * image_id field will be unchanged (and should be NULL).
3723 static int rbd_dev_image_id(struct rbd_device *rbd_dev)
3732 * When probing a parent image, the image id is already
3733 * known (and the image name likely is not). There's no
3734 * need to fetch the image id again in this case.
3736 if (rbd_dev->spec->image_id)
3740 * First, see if the format 2 image id file exists, and if
3741 * so, get the image's persistent id from it.
3743 size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name);
3744 object_name = kmalloc(size, GFP_NOIO);
3747 sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name);
3748 dout("rbd id object name is %s\n", object_name);
3750 /* Response will be an encoded string, which includes a length */
3752 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
3753 response = kzalloc(size, GFP_NOIO);
3759 ret = rbd_obj_method_sync(rbd_dev, object_name,
3762 response, RBD_IMAGE_ID_LEN_MAX, NULL);
3763 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3768 rbd_dev->spec->image_id = ceph_extract_encoded_string(&p,
3769 p + RBD_IMAGE_ID_LEN_MAX,
3771 if (IS_ERR(rbd_dev->spec->image_id)) {
3772 ret = PTR_ERR(rbd_dev->spec->image_id);
3773 rbd_dev->spec->image_id = NULL;
3775 dout("image_id is %s\n", rbd_dev->spec->image_id);
3784 static int rbd_dev_v1_probe(struct rbd_device *rbd_dev)
3789 /* Version 1 images have no id; empty string is used */
3791 rbd_dev->spec->image_id = kstrdup("", GFP_KERNEL);
3792 if (!rbd_dev->spec->image_id)
3795 /* Record the header object name for this rbd image. */
3797 size = strlen(rbd_dev->spec->image_name) + sizeof (RBD_SUFFIX);
3798 rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
3799 if (!rbd_dev->header_name) {
3803 sprintf(rbd_dev->header_name, "%s%s",
3804 rbd_dev->spec->image_name, RBD_SUFFIX);
3806 /* Populate rbd image metadata */
3808 ret = rbd_read_header(rbd_dev, &rbd_dev->header);
3812 /* Version 1 images have no parent (no layering) */
3814 rbd_dev->parent_spec = NULL;
3815 rbd_dev->parent_overlap = 0;
3817 rbd_dev->image_format = 1;
3819 dout("discovered version 1 image, header name is %s\n",
3820 rbd_dev->header_name);
3825 kfree(rbd_dev->header_name);
3826 rbd_dev->header_name = NULL;
3827 kfree(rbd_dev->spec->image_id);
3828 rbd_dev->spec->image_id = NULL;
3833 static int rbd_dev_v2_probe(struct rbd_device *rbd_dev)
3840 * Image id was filled in by the caller. Record the header
3841 * object name for this rbd image.
3843 size = sizeof (RBD_HEADER_PREFIX) + strlen(rbd_dev->spec->image_id);
3844 rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
3845 if (!rbd_dev->header_name)
3847 sprintf(rbd_dev->header_name, "%s%s",
3848 RBD_HEADER_PREFIX, rbd_dev->spec->image_id);
3850 /* Get the size and object order for the image */
3852 ret = rbd_dev_v2_image_size(rbd_dev);
3856 /* Get the object prefix (a.k.a. block_name) for the image */
3858 ret = rbd_dev_v2_object_prefix(rbd_dev);
3862 /* Get the and check features for the image */
3864 ret = rbd_dev_v2_features(rbd_dev);
3868 /* If the image supports layering, get the parent info */
3870 if (rbd_dev->header.features & RBD_FEATURE_LAYERING) {
3871 ret = rbd_dev_v2_parent_info(rbd_dev);
3876 /* crypto and compression type aren't (yet) supported for v2 images */
3878 rbd_dev->header.crypt_type = 0;
3879 rbd_dev->header.comp_type = 0;
3881 /* Get the snapshot context, plus the header version */
3883 ret = rbd_dev_v2_snap_context(rbd_dev, &ver);
3886 rbd_dev->header.obj_version = ver;
3888 rbd_dev->image_format = 2;
3890 dout("discovered version 2 image, header name is %s\n",
3891 rbd_dev->header_name);
3895 rbd_dev->parent_overlap = 0;
3896 rbd_spec_put(rbd_dev->parent_spec);
3897 rbd_dev->parent_spec = NULL;
3898 kfree(rbd_dev->header_name);
3899 rbd_dev->header_name = NULL;
3900 kfree(rbd_dev->header.object_prefix);
3901 rbd_dev->header.object_prefix = NULL;
3906 static int rbd_dev_probe_finish(struct rbd_device *rbd_dev)
3910 /* no need to lock here, as rbd_dev is not registered yet */
3911 ret = rbd_dev_snaps_update(rbd_dev);
3915 ret = rbd_dev_probe_update_spec(rbd_dev);
3919 ret = rbd_dev_set_mapping(rbd_dev);
3923 /* generate unique id: find highest unique id, add one */
3924 rbd_dev_id_get(rbd_dev);
3926 /* Fill in the device name, now that we have its id. */
3927 BUILD_BUG_ON(DEV_NAME_LEN
3928 < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
3929 sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id);
3931 /* Get our block major device number. */
3933 ret = register_blkdev(0, rbd_dev->name);
3936 rbd_dev->major = ret;
3938 /* Set up the blkdev mapping. */
3940 ret = rbd_init_disk(rbd_dev);
3942 goto err_out_blkdev;
3944 ret = rbd_bus_add_dev(rbd_dev);
3949 * At this point cleanup in the event of an error is the job
3950 * of the sysfs code (initiated by rbd_bus_del_dev()).
3952 down_write(&rbd_dev->header_rwsem);
3953 ret = rbd_dev_snaps_register(rbd_dev);
3954 up_write(&rbd_dev->header_rwsem);
3958 ret = rbd_dev_header_watch_sync(rbd_dev, 1);
3962 /* Everything's ready. Announce the disk to the world. */
3964 add_disk(rbd_dev->disk);
3966 pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name,
3967 (unsigned long long) rbd_dev->mapping.size);
3971 /* this will also clean up rest of rbd_dev stuff */
3973 rbd_bus_del_dev(rbd_dev);
3977 rbd_free_disk(rbd_dev);
3979 unregister_blkdev(rbd_dev->major, rbd_dev->name);
3981 rbd_dev_id_put(rbd_dev);
3983 rbd_remove_all_snaps(rbd_dev);
3989 * Probe for the existence of the header object for the given rbd
3990 * device. For format 2 images this includes determining the image
3993 static int rbd_dev_probe(struct rbd_device *rbd_dev)
3998 * Get the id from the image id object. If it's not a
3999 * format 2 image, we'll get ENOENT back, and we'll assume
4000 * it's a format 1 image.
4002 ret = rbd_dev_image_id(rbd_dev);
4004 ret = rbd_dev_v1_probe(rbd_dev);
4006 ret = rbd_dev_v2_probe(rbd_dev);
4008 dout("probe failed, returning %d\n", ret);
4013 ret = rbd_dev_probe_finish(rbd_dev);
4015 rbd_header_free(&rbd_dev->header);
4020 static ssize_t rbd_add(struct bus_type *bus,
4024 struct rbd_device *rbd_dev = NULL;
4025 struct ceph_options *ceph_opts = NULL;
4026 struct rbd_options *rbd_opts = NULL;
4027 struct rbd_spec *spec = NULL;
4028 struct rbd_client *rbdc;
4029 struct ceph_osd_client *osdc;
4032 if (!try_module_get(THIS_MODULE))
4035 /* parse add command */
4036 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
4038 goto err_out_module;
4040 rbdc = rbd_get_client(ceph_opts);
4045 ceph_opts = NULL; /* rbd_dev client now owns this */
4048 osdc = &rbdc->client->osdc;
4049 rc = ceph_pg_poolid_by_name(osdc->osdmap, spec->pool_name);
4051 goto err_out_client;
4052 spec->pool_id = (u64) rc;
4054 /* The ceph file layout needs to fit pool id in 32 bits */
4056 if (WARN_ON(spec->pool_id > (u64) U32_MAX)) {
4058 goto err_out_client;
4061 rbd_dev = rbd_dev_create(rbdc, spec);
4063 goto err_out_client;
4064 rbdc = NULL; /* rbd_dev now owns this */
4065 spec = NULL; /* rbd_dev now owns this */
4067 rbd_dev->mapping.read_only = rbd_opts->read_only;
4069 rbd_opts = NULL; /* done with this */
4071 rc = rbd_dev_probe(rbd_dev);
4073 goto err_out_rbd_dev;
4077 rbd_dev_destroy(rbd_dev);
4079 rbd_put_client(rbdc);
4082 ceph_destroy_options(ceph_opts);
4086 module_put(THIS_MODULE);
4088 dout("Error adding device %s\n", buf);
4090 return (ssize_t) rc;
4093 static struct rbd_device *__rbd_get_dev(unsigned long dev_id)
4095 struct list_head *tmp;
4096 struct rbd_device *rbd_dev;
4098 spin_lock(&rbd_dev_list_lock);
4099 list_for_each(tmp, &rbd_dev_list) {
4100 rbd_dev = list_entry(tmp, struct rbd_device, node);
4101 if (rbd_dev->dev_id == dev_id) {
4102 spin_unlock(&rbd_dev_list_lock);
4106 spin_unlock(&rbd_dev_list_lock);
4110 static void rbd_dev_release(struct device *dev)
4112 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4114 if (rbd_dev->watch_event)
4115 rbd_dev_header_watch_sync(rbd_dev, 0);
4117 /* clean up and free blkdev */
4118 rbd_free_disk(rbd_dev);
4119 unregister_blkdev(rbd_dev->major, rbd_dev->name);
4121 /* release allocated disk header fields */
4122 rbd_header_free(&rbd_dev->header);
4124 /* done with the id, and with the rbd_dev */
4125 rbd_dev_id_put(rbd_dev);
4126 rbd_assert(rbd_dev->rbd_client != NULL);
4127 rbd_dev_destroy(rbd_dev);
4129 /* release module ref */
4130 module_put(THIS_MODULE);
4133 static ssize_t rbd_remove(struct bus_type *bus,
4137 struct rbd_device *rbd_dev = NULL;
4142 rc = strict_strtoul(buf, 10, &ul);
4146 /* convert to int; abort if we lost anything in the conversion */
4147 target_id = (int) ul;
4148 if (target_id != ul)
4151 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
4153 rbd_dev = __rbd_get_dev(target_id);
4159 spin_lock_irq(&rbd_dev->lock);
4160 if (rbd_dev->open_count)
4163 set_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags);
4164 spin_unlock_irq(&rbd_dev->lock);
4168 rbd_remove_all_snaps(rbd_dev);
4169 rbd_bus_del_dev(rbd_dev);
4172 mutex_unlock(&ctl_mutex);
4178 * create control files in sysfs
4181 static int rbd_sysfs_init(void)
4185 ret = device_register(&rbd_root_dev);
4189 ret = bus_register(&rbd_bus_type);
4191 device_unregister(&rbd_root_dev);
4196 static void rbd_sysfs_cleanup(void)
4198 bus_unregister(&rbd_bus_type);
4199 device_unregister(&rbd_root_dev);
4202 static int __init rbd_init(void)
4206 if (!libceph_compatible(NULL)) {
4207 rbd_warn(NULL, "libceph incompatibility (quitting)");
4211 rc = rbd_sysfs_init();
4214 pr_info("loaded " RBD_DRV_NAME_LONG "\n");
4218 static void __exit rbd_exit(void)
4220 rbd_sysfs_cleanup();
4223 module_init(rbd_init);
4224 module_exit(rbd_exit);
4226 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
4227 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
4228 MODULE_DESCRIPTION("rados block device");
4230 /* following authorship retained from original osdblk.c */
4231 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
4233 MODULE_LICENSE("GPL");