3 rbd.c -- Export ceph rados objects as a Linux block device
6 based on drivers/block/osdblk.c:
8 Copyright 2009 Red Hat, Inc.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; see the file COPYING. If not, write to
21 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
25 For usage instructions, please refer to:
27 Documentation/ABI/testing/sysfs-bus-rbd
31 #include <linux/ceph/libceph.h>
32 #include <linux/ceph/osd_client.h>
33 #include <linux/ceph/mon_client.h>
34 #include <linux/ceph/decode.h>
35 #include <linux/parser.h>
36 #include <linux/bsearch.h>
38 #include <linux/kernel.h>
39 #include <linux/device.h>
40 #include <linux/module.h>
42 #include <linux/blkdev.h>
43 #include <linux/slab.h>
45 #include "rbd_types.h"
47 #define RBD_DEBUG /* Activate rbd_assert() calls */
50 * The basic unit of block I/O is a sector. It is interpreted in a
51 * number of contexts in Linux (blk, bio, genhd), but the default is
52 * universally 512 bytes. These symbols are just slightly more
53 * meaningful than the bare numbers they represent.
55 #define SECTOR_SHIFT 9
56 #define SECTOR_SIZE (1ULL << SECTOR_SHIFT)
58 #define RBD_DRV_NAME "rbd"
59 #define RBD_DRV_NAME_LONG "rbd (rados block device)"
61 #define RBD_MINORS_PER_MAJOR 256 /* max minors per blkdev */
63 #define RBD_SNAP_DEV_NAME_PREFIX "snap_"
64 #define RBD_MAX_SNAP_NAME_LEN \
65 (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1))
67 #define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */
69 #define RBD_SNAP_HEAD_NAME "-"
71 #define BAD_SNAP_INDEX U32_MAX /* invalid index into snap array */
73 /* This allows a single page to hold an image name sent by OSD */
74 #define RBD_IMAGE_NAME_LEN_MAX (PAGE_SIZE - sizeof (__le32) - 1)
75 #define RBD_IMAGE_ID_LEN_MAX 64
77 #define RBD_OBJ_PREFIX_LEN_MAX 64
81 #define RBD_FEATURE_LAYERING (1<<0)
82 #define RBD_FEATURE_STRIPINGV2 (1<<1)
83 #define RBD_FEATURES_ALL \
84 (RBD_FEATURE_LAYERING | RBD_FEATURE_STRIPINGV2)
86 /* Features supported by this (client software) implementation. */
88 #define RBD_FEATURES_SUPPORTED (RBD_FEATURES_ALL)
91 * An RBD device name will be "rbd#", where the "rbd" comes from
92 * RBD_DRV_NAME above, and # is a unique integer identifier.
93 * MAX_INT_FORMAT_WIDTH is used in ensuring DEV_NAME_LEN is big
94 * enough to hold all possible device names.
96 #define DEV_NAME_LEN 32
97 #define MAX_INT_FORMAT_WIDTH ((5 * sizeof (int)) / 2 + 1)
100 * block device image metadata (in-memory version)
102 struct rbd_image_header {
103 /* These four fields never change for a given rbd image */
110 /* The remaining fields need to be updated occasionally */
112 struct ceph_snap_context *snapc;
121 * An rbd image specification.
123 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely
124 * identify an image. Each rbd_dev structure includes a pointer to
125 * an rbd_spec structure that encapsulates this identity.
127 * Each of the id's in an rbd_spec has an associated name. For a
128 * user-mapped image, the names are supplied and the id's associated
129 * with them are looked up. For a layered image, a parent image is
130 * defined by the tuple, and the names are looked up.
132 * An rbd_dev structure contains a parent_spec pointer which is
133 * non-null if the image it represents is a child in a layered
134 * image. This pointer will refer to the rbd_spec structure used
135 * by the parent rbd_dev for its own identity (i.e., the structure
136 * is shared between the parent and child).
138 * Since these structures are populated once, during the discovery
139 * phase of image construction, they are effectively immutable so
140 * we make no effort to synchronize access to them.
142 * Note that code herein does not assume the image name is known (it
143 * could be a null pointer).
147 const char *pool_name;
149 const char *image_id;
150 const char *image_name;
153 const char *snap_name;
159 * an instance of the client. multiple devices may share an rbd client.
162 struct ceph_client *client;
164 struct list_head node;
167 struct rbd_img_request;
168 typedef void (*rbd_img_callback_t)(struct rbd_img_request *);
170 #define BAD_WHICH U32_MAX /* Good which or bad which, which? */
172 struct rbd_obj_request;
173 typedef void (*rbd_obj_callback_t)(struct rbd_obj_request *);
175 enum obj_request_type {
176 OBJ_REQUEST_NODATA, OBJ_REQUEST_BIO, OBJ_REQUEST_PAGES
180 OBJ_REQ_DONE, /* completion flag: not done = 0, done = 1 */
181 OBJ_REQ_IMG_DATA, /* object usage: standalone = 0, image = 1 */
182 OBJ_REQ_KNOWN, /* EXISTS flag valid: no = 0, yes = 1 */
183 OBJ_REQ_EXISTS, /* target exists: no = 0, yes = 1 */
186 struct rbd_obj_request {
187 const char *object_name;
188 u64 offset; /* object start byte */
189 u64 length; /* bytes from offset */
193 * An object request associated with an image will have its
194 * img_data flag set; a standalone object request will not.
196 * A standalone object request will have which == BAD_WHICH
197 * and a null obj_request pointer.
199 * An object request initiated in support of a layered image
200 * object (to check for its existence before a write) will
201 * have which == BAD_WHICH and a non-null obj_request pointer.
203 * Finally, an object request for rbd image data will have
204 * which != BAD_WHICH, and will have a non-null img_request
205 * pointer. The value of which will be in the range
206 * 0..(img_request->obj_request_count-1).
209 struct rbd_obj_request *obj_request; /* STAT op */
211 struct rbd_img_request *img_request;
213 /* links for img_request->obj_requests list */
214 struct list_head links;
217 u32 which; /* posn image request list */
219 enum obj_request_type type;
221 struct bio *bio_list;
227 struct page **copyup_pages;
229 struct ceph_osd_request *osd_req;
231 u64 xferred; /* bytes transferred */
234 rbd_obj_callback_t callback;
235 struct completion completion;
241 IMG_REQ_WRITE, /* I/O direction: read = 0, write = 1 */
242 IMG_REQ_CHILD, /* initiator: block = 0, child image = 1 */
243 IMG_REQ_LAYERED, /* ENOENT handling: normal = 0, layered = 1 */
246 struct rbd_img_request {
247 struct rbd_device *rbd_dev;
248 u64 offset; /* starting image byte offset */
249 u64 length; /* byte count from offset */
252 u64 snap_id; /* for reads */
253 struct ceph_snap_context *snapc; /* for writes */
256 struct request *rq; /* block request */
257 struct rbd_obj_request *obj_request; /* obj req initiator */
259 struct page **copyup_pages;
260 spinlock_t completion_lock;/* protects next_completion */
262 rbd_img_callback_t callback;
263 u64 xferred;/* aggregate bytes transferred */
264 int result; /* first nonzero obj_request result */
266 u32 obj_request_count;
267 struct list_head obj_requests; /* rbd_obj_request structs */
272 #define for_each_obj_request(ireq, oreq) \
273 list_for_each_entry(oreq, &(ireq)->obj_requests, links)
274 #define for_each_obj_request_from(ireq, oreq) \
275 list_for_each_entry_from(oreq, &(ireq)->obj_requests, links)
276 #define for_each_obj_request_safe(ireq, oreq, n) \
277 list_for_each_entry_safe_reverse(oreq, n, &(ireq)->obj_requests, links)
289 int dev_id; /* blkdev unique id */
291 int major; /* blkdev assigned major */
292 struct gendisk *disk; /* blkdev's gendisk and rq */
294 u32 image_format; /* Either 1 or 2 */
295 struct rbd_client *rbd_client;
297 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */
299 spinlock_t lock; /* queue, flags, open_count */
301 struct rbd_image_header header;
302 unsigned long flags; /* possibly lock protected */
303 struct rbd_spec *spec;
307 struct ceph_file_layout layout;
309 struct ceph_osd_event *watch_event;
310 struct rbd_obj_request *watch_request;
312 struct rbd_spec *parent_spec;
314 struct rbd_device *parent;
316 /* protects updating the header */
317 struct rw_semaphore header_rwsem;
319 struct rbd_mapping mapping;
321 struct list_head node;
325 unsigned long open_count; /* protected by lock */
329 * Flag bits for rbd_dev->flags. If atomicity is required,
330 * rbd_dev->lock is used to protect access.
332 * Currently, only the "removing" flag (which is coupled with the
333 * "open_count" field) requires atomic access.
336 RBD_DEV_FLAG_EXISTS, /* mapped snapshot has not been deleted */
337 RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */
340 static DEFINE_MUTEX(ctl_mutex); /* Serialize open/close/setup/teardown */
342 static LIST_HEAD(rbd_dev_list); /* devices */
343 static DEFINE_SPINLOCK(rbd_dev_list_lock);
345 static LIST_HEAD(rbd_client_list); /* clients */
346 static DEFINE_SPINLOCK(rbd_client_list_lock);
348 static struct kmem_cache *rbd_img_request_cache;
350 static int rbd_img_request_submit(struct rbd_img_request *img_request);
352 static void rbd_dev_device_release(struct device *dev);
354 static ssize_t rbd_add(struct bus_type *bus, const char *buf,
356 static ssize_t rbd_remove(struct bus_type *bus, const char *buf,
358 static int rbd_dev_image_probe(struct rbd_device *rbd_dev);
360 static struct bus_attribute rbd_bus_attrs[] = {
361 __ATTR(add, S_IWUSR, NULL, rbd_add),
362 __ATTR(remove, S_IWUSR, NULL, rbd_remove),
366 static struct bus_type rbd_bus_type = {
368 .bus_attrs = rbd_bus_attrs,
371 static void rbd_root_dev_release(struct device *dev)
375 static struct device rbd_root_dev = {
377 .release = rbd_root_dev_release,
380 static __printf(2, 3)
381 void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...)
383 struct va_format vaf;
391 printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf);
392 else if (rbd_dev->disk)
393 printk(KERN_WARNING "%s: %s: %pV\n",
394 RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf);
395 else if (rbd_dev->spec && rbd_dev->spec->image_name)
396 printk(KERN_WARNING "%s: image %s: %pV\n",
397 RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf);
398 else if (rbd_dev->spec && rbd_dev->spec->image_id)
399 printk(KERN_WARNING "%s: id %s: %pV\n",
400 RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf);
402 printk(KERN_WARNING "%s: rbd_dev %p: %pV\n",
403 RBD_DRV_NAME, rbd_dev, &vaf);
408 #define rbd_assert(expr) \
409 if (unlikely(!(expr))) { \
410 printk(KERN_ERR "\nAssertion failure in %s() " \
412 "\trbd_assert(%s);\n\n", \
413 __func__, __LINE__, #expr); \
416 #else /* !RBD_DEBUG */
417 # define rbd_assert(expr) ((void) 0)
418 #endif /* !RBD_DEBUG */
420 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request);
421 static void rbd_img_parent_read(struct rbd_obj_request *obj_request);
422 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev);
424 static int rbd_dev_refresh(struct rbd_device *rbd_dev);
425 static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev);
426 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
428 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
429 u8 *order, u64 *snap_size);
430 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
432 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name);
434 static int rbd_open(struct block_device *bdev, fmode_t mode)
436 struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
437 bool removing = false;
439 if ((mode & FMODE_WRITE) && rbd_dev->mapping.read_only)
442 spin_lock_irq(&rbd_dev->lock);
443 if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags))
446 rbd_dev->open_count++;
447 spin_unlock_irq(&rbd_dev->lock);
451 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
452 (void) get_device(&rbd_dev->dev);
453 set_device_ro(bdev, rbd_dev->mapping.read_only);
454 mutex_unlock(&ctl_mutex);
459 static int rbd_release(struct gendisk *disk, fmode_t mode)
461 struct rbd_device *rbd_dev = disk->private_data;
462 unsigned long open_count_before;
464 spin_lock_irq(&rbd_dev->lock);
465 open_count_before = rbd_dev->open_count--;
466 spin_unlock_irq(&rbd_dev->lock);
467 rbd_assert(open_count_before > 0);
469 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
470 put_device(&rbd_dev->dev);
471 mutex_unlock(&ctl_mutex);
476 static const struct block_device_operations rbd_bd_ops = {
477 .owner = THIS_MODULE,
479 .release = rbd_release,
483 * Initialize an rbd client instance.
486 static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
488 struct rbd_client *rbdc;
491 dout("%s:\n", __func__);
492 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
496 kref_init(&rbdc->kref);
497 INIT_LIST_HEAD(&rbdc->node);
499 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
501 rbdc->client = ceph_create_client(ceph_opts, rbdc, 0, 0);
502 if (IS_ERR(rbdc->client))
504 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
506 ret = ceph_open_session(rbdc->client);
510 spin_lock(&rbd_client_list_lock);
511 list_add_tail(&rbdc->node, &rbd_client_list);
512 spin_unlock(&rbd_client_list_lock);
514 mutex_unlock(&ctl_mutex);
515 dout("%s: rbdc %p\n", __func__, rbdc);
520 ceph_destroy_client(rbdc->client);
522 mutex_unlock(&ctl_mutex);
526 ceph_destroy_options(ceph_opts);
527 dout("%s: error %d\n", __func__, ret);
532 static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
534 kref_get(&rbdc->kref);
540 * Find a ceph client with specific addr and configuration. If
541 * found, bump its reference count.
543 static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
545 struct rbd_client *client_node;
548 if (ceph_opts->flags & CEPH_OPT_NOSHARE)
551 spin_lock(&rbd_client_list_lock);
552 list_for_each_entry(client_node, &rbd_client_list, node) {
553 if (!ceph_compare_options(ceph_opts, client_node->client)) {
554 __rbd_get_client(client_node);
560 spin_unlock(&rbd_client_list_lock);
562 return found ? client_node : NULL;
572 /* string args above */
575 /* Boolean args above */
579 static match_table_t rbd_opts_tokens = {
581 /* string args above */
582 {Opt_read_only, "read_only"},
583 {Opt_read_only, "ro"}, /* Alternate spelling */
584 {Opt_read_write, "read_write"},
585 {Opt_read_write, "rw"}, /* Alternate spelling */
586 /* Boolean args above */
594 #define RBD_READ_ONLY_DEFAULT false
596 static int parse_rbd_opts_token(char *c, void *private)
598 struct rbd_options *rbd_opts = private;
599 substring_t argstr[MAX_OPT_ARGS];
600 int token, intval, ret;
602 token = match_token(c, rbd_opts_tokens, argstr);
606 if (token < Opt_last_int) {
607 ret = match_int(&argstr[0], &intval);
609 pr_err("bad mount option arg (not int) "
613 dout("got int token %d val %d\n", token, intval);
614 } else if (token > Opt_last_int && token < Opt_last_string) {
615 dout("got string token %d val %s\n", token,
617 } else if (token > Opt_last_string && token < Opt_last_bool) {
618 dout("got Boolean token %d\n", token);
620 dout("got token %d\n", token);
625 rbd_opts->read_only = true;
628 rbd_opts->read_only = false;
638 * Get a ceph client with specific addr and configuration, if one does
639 * not exist create it.
641 static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
643 struct rbd_client *rbdc;
645 rbdc = rbd_client_find(ceph_opts);
646 if (rbdc) /* using an existing client */
647 ceph_destroy_options(ceph_opts);
649 rbdc = rbd_client_create(ceph_opts);
655 * Destroy ceph client
657 * Caller must hold rbd_client_list_lock.
659 static void rbd_client_release(struct kref *kref)
661 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
663 dout("%s: rbdc %p\n", __func__, rbdc);
664 spin_lock(&rbd_client_list_lock);
665 list_del(&rbdc->node);
666 spin_unlock(&rbd_client_list_lock);
668 ceph_destroy_client(rbdc->client);
673 * Drop reference to ceph client node. If it's not referenced anymore, release
676 static void rbd_put_client(struct rbd_client *rbdc)
679 kref_put(&rbdc->kref, rbd_client_release);
682 static bool rbd_image_format_valid(u32 image_format)
684 return image_format == 1 || image_format == 2;
687 static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
692 /* The header has to start with the magic rbd header text */
693 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
696 /* The bio layer requires at least sector-sized I/O */
698 if (ondisk->options.order < SECTOR_SHIFT)
701 /* If we use u64 in a few spots we may be able to loosen this */
703 if (ondisk->options.order > 8 * sizeof (int) - 1)
707 * The size of a snapshot header has to fit in a size_t, and
708 * that limits the number of snapshots.
710 snap_count = le32_to_cpu(ondisk->snap_count);
711 size = SIZE_MAX - sizeof (struct ceph_snap_context);
712 if (snap_count > size / sizeof (__le64))
716 * Not only that, but the size of the entire the snapshot
717 * header must also be representable in a size_t.
719 size -= snap_count * sizeof (__le64);
720 if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
727 * Create a new header structure, translate header format from the on-disk
730 static int rbd_header_from_disk(struct rbd_image_header *header,
731 struct rbd_image_header_ondisk *ondisk)
738 memset(header, 0, sizeof (*header));
740 snap_count = le32_to_cpu(ondisk->snap_count);
742 len = strnlen(ondisk->object_prefix, sizeof (ondisk->object_prefix));
743 header->object_prefix = kmalloc(len + 1, GFP_KERNEL);
744 if (!header->object_prefix)
746 memcpy(header->object_prefix, ondisk->object_prefix, len);
747 header->object_prefix[len] = '\0';
750 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);
752 /* Save a copy of the snapshot names */
754 if (snap_names_len > (u64) SIZE_MAX)
756 header->snap_names = kmalloc(snap_names_len, GFP_KERNEL);
757 if (!header->snap_names)
760 * Note that rbd_dev_v1_header_read() guarantees
761 * the ondisk buffer we're working with has
762 * snap_names_len bytes beyond the end of the
763 * snapshot id array, this memcpy() is safe.
765 memcpy(header->snap_names, &ondisk->snaps[snap_count],
768 /* Record each snapshot's size */
770 size = snap_count * sizeof (*header->snap_sizes);
771 header->snap_sizes = kmalloc(size, GFP_KERNEL);
772 if (!header->snap_sizes)
774 for (i = 0; i < snap_count; i++)
775 header->snap_sizes[i] =
776 le64_to_cpu(ondisk->snaps[i].image_size);
778 header->snap_names = NULL;
779 header->snap_sizes = NULL;
782 header->features = 0; /* No features support in v1 images */
783 header->obj_order = ondisk->options.order;
784 header->crypt_type = ondisk->options.crypt_type;
785 header->comp_type = ondisk->options.comp_type;
787 /* Allocate and fill in the snapshot context */
789 header->image_size = le64_to_cpu(ondisk->image_size);
791 header->snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
794 header->snapc->seq = le64_to_cpu(ondisk->snap_seq);
795 for (i = 0; i < snap_count; i++)
796 header->snapc->snaps[i] = le64_to_cpu(ondisk->snaps[i].id);
801 kfree(header->snap_sizes);
802 header->snap_sizes = NULL;
803 kfree(header->snap_names);
804 header->snap_names = NULL;
805 kfree(header->object_prefix);
806 header->object_prefix = NULL;
811 static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
813 const char *snap_name;
815 rbd_assert(which < rbd_dev->header.snapc->num_snaps);
817 /* Skip over names until we find the one we are looking for */
819 snap_name = rbd_dev->header.snap_names;
821 snap_name += strlen(snap_name) + 1;
823 return kstrdup(snap_name, GFP_KERNEL);
827 * Snapshot id comparison function for use with qsort()/bsearch().
828 * Note that result is for snapshots in *descending* order.
830 static int snapid_compare_reverse(const void *s1, const void *s2)
832 u64 snap_id1 = *(u64 *)s1;
833 u64 snap_id2 = *(u64 *)s2;
835 if (snap_id1 < snap_id2)
837 return snap_id1 == snap_id2 ? 0 : -1;
841 * Search a snapshot context to see if the given snapshot id is
844 * Returns the position of the snapshot id in the array if it's found,
845 * or BAD_SNAP_INDEX otherwise.
847 * Note: The snapshot array is in kept sorted (by the osd) in
848 * reverse order, highest snapshot id first.
850 static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id)
852 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
855 found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps,
856 sizeof (snap_id), snapid_compare_reverse);
858 return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX;
861 static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
866 which = rbd_dev_snap_index(rbd_dev, snap_id);
867 if (which == BAD_SNAP_INDEX)
870 return _rbd_dev_v1_snap_name(rbd_dev, which);
873 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
875 if (snap_id == CEPH_NOSNAP)
876 return RBD_SNAP_HEAD_NAME;
878 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
879 if (rbd_dev->image_format == 1)
880 return rbd_dev_v1_snap_name(rbd_dev, snap_id);
882 return rbd_dev_v2_snap_name(rbd_dev, snap_id);
885 static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
888 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
889 if (snap_id == CEPH_NOSNAP) {
890 *snap_size = rbd_dev->header.image_size;
891 } else if (rbd_dev->image_format == 1) {
894 which = rbd_dev_snap_index(rbd_dev, snap_id);
895 if (which == BAD_SNAP_INDEX)
898 *snap_size = rbd_dev->header.snap_sizes[which];
903 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
912 static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
915 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
916 if (snap_id == CEPH_NOSNAP) {
917 *snap_features = rbd_dev->header.features;
918 } else if (rbd_dev->image_format == 1) {
919 *snap_features = 0; /* No features for format 1 */
924 ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features);
928 *snap_features = features;
933 static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
935 const char *snap_name = rbd_dev->spec->snap_name;
941 if (strcmp(snap_name, RBD_SNAP_HEAD_NAME)) {
942 snap_id = rbd_snap_id_by_name(rbd_dev, snap_name);
943 if (snap_id == CEPH_NOSNAP)
946 snap_id = CEPH_NOSNAP;
949 ret = rbd_snap_size(rbd_dev, snap_id, &size);
952 ret = rbd_snap_features(rbd_dev, snap_id, &features);
956 rbd_dev->mapping.size = size;
957 rbd_dev->mapping.features = features;
959 /* If we are mapping a snapshot it must be marked read-only */
961 if (snap_id != CEPH_NOSNAP)
962 rbd_dev->mapping.read_only = true;
967 static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
969 rbd_dev->mapping.size = 0;
970 rbd_dev->mapping.features = 0;
971 rbd_dev->mapping.read_only = true;
974 static void rbd_dev_clear_mapping(struct rbd_device *rbd_dev)
976 rbd_dev->mapping.size = 0;
977 rbd_dev->mapping.features = 0;
978 rbd_dev->mapping.read_only = true;
981 static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset)
987 name = kmalloc(MAX_OBJ_NAME_SIZE + 1, GFP_NOIO);
990 segment = offset >> rbd_dev->header.obj_order;
991 ret = snprintf(name, MAX_OBJ_NAME_SIZE + 1, "%s.%012llx",
992 rbd_dev->header.object_prefix, segment);
993 if (ret < 0 || ret > MAX_OBJ_NAME_SIZE) {
994 pr_err("error formatting segment name for #%llu (%d)\n",
1003 static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset)
1005 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1007 return offset & (segment_size - 1);
1010 static u64 rbd_segment_length(struct rbd_device *rbd_dev,
1011 u64 offset, u64 length)
1013 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1015 offset &= segment_size - 1;
1017 rbd_assert(length <= U64_MAX - offset);
1018 if (offset + length > segment_size)
1019 length = segment_size - offset;
1025 * returns the size of an object in the image
1027 static u64 rbd_obj_bytes(struct rbd_image_header *header)
1029 return 1 << header->obj_order;
1036 static void bio_chain_put(struct bio *chain)
1042 chain = chain->bi_next;
1048 * zeros a bio chain, starting at specific offset
1050 static void zero_bio_chain(struct bio *chain, int start_ofs)
1053 unsigned long flags;
1059 bio_for_each_segment(bv, chain, i) {
1060 if (pos + bv->bv_len > start_ofs) {
1061 int remainder = max(start_ofs - pos, 0);
1062 buf = bvec_kmap_irq(bv, &flags);
1063 memset(buf + remainder, 0,
1064 bv->bv_len - remainder);
1065 bvec_kunmap_irq(buf, &flags);
1070 chain = chain->bi_next;
1075 * similar to zero_bio_chain(), zeros data defined by a page array,
1076 * starting at the given byte offset from the start of the array and
1077 * continuing up to the given end offset. The pages array is
1078 * assumed to be big enough to hold all bytes up to the end.
1080 static void zero_pages(struct page **pages, u64 offset, u64 end)
1082 struct page **page = &pages[offset >> PAGE_SHIFT];
1084 rbd_assert(end > offset);
1085 rbd_assert(end - offset <= (u64)SIZE_MAX);
1086 while (offset < end) {
1089 unsigned long flags;
1092 page_offset = (size_t)(offset & ~PAGE_MASK);
1093 length = min(PAGE_SIZE - page_offset, (size_t)(end - offset));
1094 local_irq_save(flags);
1095 kaddr = kmap_atomic(*page);
1096 memset(kaddr + page_offset, 0, length);
1097 kunmap_atomic(kaddr);
1098 local_irq_restore(flags);
1106 * Clone a portion of a bio, starting at the given byte offset
1107 * and continuing for the number of bytes indicated.
1109 static struct bio *bio_clone_range(struct bio *bio_src,
1110 unsigned int offset,
1118 unsigned short end_idx;
1119 unsigned short vcnt;
1122 /* Handle the easy case for the caller */
1124 if (!offset && len == bio_src->bi_size)
1125 return bio_clone(bio_src, gfpmask);
1127 if (WARN_ON_ONCE(!len))
1129 if (WARN_ON_ONCE(len > bio_src->bi_size))
1131 if (WARN_ON_ONCE(offset > bio_src->bi_size - len))
1134 /* Find first affected segment... */
1137 __bio_for_each_segment(bv, bio_src, idx, 0) {
1138 if (resid < bv->bv_len)
1140 resid -= bv->bv_len;
1144 /* ...and the last affected segment */
1147 __bio_for_each_segment(bv, bio_src, end_idx, idx) {
1148 if (resid <= bv->bv_len)
1150 resid -= bv->bv_len;
1152 vcnt = end_idx - idx + 1;
1154 /* Build the clone */
1156 bio = bio_alloc(gfpmask, (unsigned int) vcnt);
1158 return NULL; /* ENOMEM */
1160 bio->bi_bdev = bio_src->bi_bdev;
1161 bio->bi_sector = bio_src->bi_sector + (offset >> SECTOR_SHIFT);
1162 bio->bi_rw = bio_src->bi_rw;
1163 bio->bi_flags |= 1 << BIO_CLONED;
1166 * Copy over our part of the bio_vec, then update the first
1167 * and last (or only) entries.
1169 memcpy(&bio->bi_io_vec[0], &bio_src->bi_io_vec[idx],
1170 vcnt * sizeof (struct bio_vec));
1171 bio->bi_io_vec[0].bv_offset += voff;
1173 bio->bi_io_vec[0].bv_len -= voff;
1174 bio->bi_io_vec[vcnt - 1].bv_len = resid;
1176 bio->bi_io_vec[0].bv_len = len;
1179 bio->bi_vcnt = vcnt;
1187 * Clone a portion of a bio chain, starting at the given byte offset
1188 * into the first bio in the source chain and continuing for the
1189 * number of bytes indicated. The result is another bio chain of
1190 * exactly the given length, or a null pointer on error.
1192 * The bio_src and offset parameters are both in-out. On entry they
1193 * refer to the first source bio and the offset into that bio where
1194 * the start of data to be cloned is located.
1196 * On return, bio_src is updated to refer to the bio in the source
1197 * chain that contains first un-cloned byte, and *offset will
1198 * contain the offset of that byte within that bio.
1200 static struct bio *bio_chain_clone_range(struct bio **bio_src,
1201 unsigned int *offset,
1205 struct bio *bi = *bio_src;
1206 unsigned int off = *offset;
1207 struct bio *chain = NULL;
1210 /* Build up a chain of clone bios up to the limit */
1212 if (!bi || off >= bi->bi_size || !len)
1213 return NULL; /* Nothing to clone */
1217 unsigned int bi_size;
1221 rbd_warn(NULL, "bio_chain exhausted with %u left", len);
1222 goto out_err; /* EINVAL; ran out of bio's */
1224 bi_size = min_t(unsigned int, bi->bi_size - off, len);
1225 bio = bio_clone_range(bi, off, bi_size, gfpmask);
1227 goto out_err; /* ENOMEM */
1230 end = &bio->bi_next;
1233 if (off == bi->bi_size) {
1244 bio_chain_put(chain);
1250 * The default/initial value for all object request flags is 0. For
1251 * each flag, once its value is set to 1 it is never reset to 0
1254 static void obj_request_img_data_set(struct rbd_obj_request *obj_request)
1256 if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) {
1257 struct rbd_device *rbd_dev;
1259 rbd_dev = obj_request->img_request->rbd_dev;
1260 rbd_warn(rbd_dev, "obj_request %p already marked img_data\n",
1265 static bool obj_request_img_data_test(struct rbd_obj_request *obj_request)
1268 return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0;
1271 static void obj_request_done_set(struct rbd_obj_request *obj_request)
1273 if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) {
1274 struct rbd_device *rbd_dev = NULL;
1276 if (obj_request_img_data_test(obj_request))
1277 rbd_dev = obj_request->img_request->rbd_dev;
1278 rbd_warn(rbd_dev, "obj_request %p already marked done\n",
1283 static bool obj_request_done_test(struct rbd_obj_request *obj_request)
1286 return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0;
1290 * This sets the KNOWN flag after (possibly) setting the EXISTS
1291 * flag. The latter is set based on the "exists" value provided.
1293 * Note that for our purposes once an object exists it never goes
1294 * away again. It's possible that the response from two existence
1295 * checks are separated by the creation of the target object, and
1296 * the first ("doesn't exist") response arrives *after* the second
1297 * ("does exist"). In that case we ignore the second one.
1299 static void obj_request_existence_set(struct rbd_obj_request *obj_request,
1303 set_bit(OBJ_REQ_EXISTS, &obj_request->flags);
1304 set_bit(OBJ_REQ_KNOWN, &obj_request->flags);
1308 static bool obj_request_known_test(struct rbd_obj_request *obj_request)
1311 return test_bit(OBJ_REQ_KNOWN, &obj_request->flags) != 0;
1314 static bool obj_request_exists_test(struct rbd_obj_request *obj_request)
1317 return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0;
1320 static void rbd_obj_request_get(struct rbd_obj_request *obj_request)
1322 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1323 atomic_read(&obj_request->kref.refcount));
1324 kref_get(&obj_request->kref);
1327 static void rbd_obj_request_destroy(struct kref *kref);
1328 static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
1330 rbd_assert(obj_request != NULL);
1331 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1332 atomic_read(&obj_request->kref.refcount));
1333 kref_put(&obj_request->kref, rbd_obj_request_destroy);
1336 static void rbd_img_request_get(struct rbd_img_request *img_request)
1338 dout("%s: img %p (was %d)\n", __func__, img_request,
1339 atomic_read(&img_request->kref.refcount));
1340 kref_get(&img_request->kref);
1343 static void rbd_img_request_destroy(struct kref *kref);
1344 static void rbd_img_request_put(struct rbd_img_request *img_request)
1346 rbd_assert(img_request != NULL);
1347 dout("%s: img %p (was %d)\n", __func__, img_request,
1348 atomic_read(&img_request->kref.refcount));
1349 kref_put(&img_request->kref, rbd_img_request_destroy);
1352 static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
1353 struct rbd_obj_request *obj_request)
1355 rbd_assert(obj_request->img_request == NULL);
1357 /* Image request now owns object's original reference */
1358 obj_request->img_request = img_request;
1359 obj_request->which = img_request->obj_request_count;
1360 rbd_assert(!obj_request_img_data_test(obj_request));
1361 obj_request_img_data_set(obj_request);
1362 rbd_assert(obj_request->which != BAD_WHICH);
1363 img_request->obj_request_count++;
1364 list_add_tail(&obj_request->links, &img_request->obj_requests);
1365 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1366 obj_request->which);
1369 static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
1370 struct rbd_obj_request *obj_request)
1372 rbd_assert(obj_request->which != BAD_WHICH);
1374 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1375 obj_request->which);
1376 list_del(&obj_request->links);
1377 rbd_assert(img_request->obj_request_count > 0);
1378 img_request->obj_request_count--;
1379 rbd_assert(obj_request->which == img_request->obj_request_count);
1380 obj_request->which = BAD_WHICH;
1381 rbd_assert(obj_request_img_data_test(obj_request));
1382 rbd_assert(obj_request->img_request == img_request);
1383 obj_request->img_request = NULL;
1384 obj_request->callback = NULL;
1385 rbd_obj_request_put(obj_request);
1388 static bool obj_request_type_valid(enum obj_request_type type)
1391 case OBJ_REQUEST_NODATA:
1392 case OBJ_REQUEST_BIO:
1393 case OBJ_REQUEST_PAGES:
1400 static int rbd_obj_request_submit(struct ceph_osd_client *osdc,
1401 struct rbd_obj_request *obj_request)
1403 dout("%s: osdc %p obj %p\n", __func__, osdc, obj_request);
1405 return ceph_osdc_start_request(osdc, obj_request->osd_req, false);
1408 static void rbd_img_request_complete(struct rbd_img_request *img_request)
1411 dout("%s: img %p\n", __func__, img_request);
1414 * If no error occurred, compute the aggregate transfer
1415 * count for the image request. We could instead use
1416 * atomic64_cmpxchg() to update it as each object request
1417 * completes; not clear which way is better off hand.
1419 if (!img_request->result) {
1420 struct rbd_obj_request *obj_request;
1423 for_each_obj_request(img_request, obj_request)
1424 xferred += obj_request->xferred;
1425 img_request->xferred = xferred;
1428 if (img_request->callback)
1429 img_request->callback(img_request);
1431 rbd_img_request_put(img_request);
1434 /* Caller is responsible for rbd_obj_request_destroy(obj_request) */
1436 static int rbd_obj_request_wait(struct rbd_obj_request *obj_request)
1438 dout("%s: obj %p\n", __func__, obj_request);
1440 return wait_for_completion_interruptible(&obj_request->completion);
1444 * The default/initial value for all image request flags is 0. Each
1445 * is conditionally set to 1 at image request initialization time
1446 * and currently never change thereafter.
1448 static void img_request_write_set(struct rbd_img_request *img_request)
1450 set_bit(IMG_REQ_WRITE, &img_request->flags);
1454 static bool img_request_write_test(struct rbd_img_request *img_request)
1457 return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0;
1460 static void img_request_child_set(struct rbd_img_request *img_request)
1462 set_bit(IMG_REQ_CHILD, &img_request->flags);
1466 static bool img_request_child_test(struct rbd_img_request *img_request)
1469 return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0;
1472 static void img_request_layered_set(struct rbd_img_request *img_request)
1474 set_bit(IMG_REQ_LAYERED, &img_request->flags);
1478 static bool img_request_layered_test(struct rbd_img_request *img_request)
1481 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
1485 rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
1487 u64 xferred = obj_request->xferred;
1488 u64 length = obj_request->length;
1490 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1491 obj_request, obj_request->img_request, obj_request->result,
1494 * ENOENT means a hole in the image. We zero-fill the
1495 * entire length of the request. A short read also implies
1496 * zero-fill to the end of the request. Either way we
1497 * update the xferred count to indicate the whole request
1500 rbd_assert(obj_request->type != OBJ_REQUEST_NODATA);
1501 if (obj_request->result == -ENOENT) {
1502 if (obj_request->type == OBJ_REQUEST_BIO)
1503 zero_bio_chain(obj_request->bio_list, 0);
1505 zero_pages(obj_request->pages, 0, length);
1506 obj_request->result = 0;
1507 obj_request->xferred = length;
1508 } else if (xferred < length && !obj_request->result) {
1509 if (obj_request->type == OBJ_REQUEST_BIO)
1510 zero_bio_chain(obj_request->bio_list, xferred);
1512 zero_pages(obj_request->pages, xferred, length);
1513 obj_request->xferred = length;
1515 obj_request_done_set(obj_request);
1518 static void rbd_obj_request_complete(struct rbd_obj_request *obj_request)
1520 dout("%s: obj %p cb %p\n", __func__, obj_request,
1521 obj_request->callback);
1522 if (obj_request->callback)
1523 obj_request->callback(obj_request);
1525 complete_all(&obj_request->completion);
1528 static void rbd_osd_trivial_callback(struct rbd_obj_request *obj_request)
1530 dout("%s: obj %p\n", __func__, obj_request);
1531 obj_request_done_set(obj_request);
1534 static void rbd_osd_read_callback(struct rbd_obj_request *obj_request)
1536 struct rbd_img_request *img_request = NULL;
1537 struct rbd_device *rbd_dev = NULL;
1538 bool layered = false;
1540 if (obj_request_img_data_test(obj_request)) {
1541 img_request = obj_request->img_request;
1542 layered = img_request && img_request_layered_test(img_request);
1543 rbd_dev = img_request->rbd_dev;
1546 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1547 obj_request, img_request, obj_request->result,
1548 obj_request->xferred, obj_request->length);
1549 if (layered && obj_request->result == -ENOENT &&
1550 obj_request->img_offset < rbd_dev->parent_overlap)
1551 rbd_img_parent_read(obj_request);
1552 else if (img_request)
1553 rbd_img_obj_request_read_callback(obj_request);
1555 obj_request_done_set(obj_request);
1558 static void rbd_osd_write_callback(struct rbd_obj_request *obj_request)
1560 dout("%s: obj %p result %d %llu\n", __func__, obj_request,
1561 obj_request->result, obj_request->length);
1563 * There is no such thing as a successful short write. Set
1564 * it to our originally-requested length.
1566 obj_request->xferred = obj_request->length;
1567 obj_request_done_set(obj_request);
1571 * For a simple stat call there's nothing to do. We'll do more if
1572 * this is part of a write sequence for a layered image.
1574 static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request)
1576 dout("%s: obj %p\n", __func__, obj_request);
1577 obj_request_done_set(obj_request);
1580 static void rbd_osd_req_callback(struct ceph_osd_request *osd_req,
1581 struct ceph_msg *msg)
1583 struct rbd_obj_request *obj_request = osd_req->r_priv;
1586 dout("%s: osd_req %p msg %p\n", __func__, osd_req, msg);
1587 rbd_assert(osd_req == obj_request->osd_req);
1588 if (obj_request_img_data_test(obj_request)) {
1589 rbd_assert(obj_request->img_request);
1590 rbd_assert(obj_request->which != BAD_WHICH);
1592 rbd_assert(obj_request->which == BAD_WHICH);
1595 if (osd_req->r_result < 0)
1596 obj_request->result = osd_req->r_result;
1598 BUG_ON(osd_req->r_num_ops > 2);
1601 * We support a 64-bit length, but ultimately it has to be
1602 * passed to blk_end_request(), which takes an unsigned int.
1604 obj_request->xferred = osd_req->r_reply_op_len[0];
1605 rbd_assert(obj_request->xferred < (u64)UINT_MAX);
1606 opcode = osd_req->r_ops[0].op;
1608 case CEPH_OSD_OP_READ:
1609 rbd_osd_read_callback(obj_request);
1611 case CEPH_OSD_OP_WRITE:
1612 rbd_osd_write_callback(obj_request);
1614 case CEPH_OSD_OP_STAT:
1615 rbd_osd_stat_callback(obj_request);
1617 case CEPH_OSD_OP_CALL:
1618 case CEPH_OSD_OP_NOTIFY_ACK:
1619 case CEPH_OSD_OP_WATCH:
1620 rbd_osd_trivial_callback(obj_request);
1623 rbd_warn(NULL, "%s: unsupported op %hu\n",
1624 obj_request->object_name, (unsigned short) opcode);
1628 if (obj_request_done_test(obj_request))
1629 rbd_obj_request_complete(obj_request);
1632 static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request)
1634 struct rbd_img_request *img_request = obj_request->img_request;
1635 struct ceph_osd_request *osd_req = obj_request->osd_req;
1638 rbd_assert(osd_req != NULL);
1640 snap_id = img_request ? img_request->snap_id : CEPH_NOSNAP;
1641 ceph_osdc_build_request(osd_req, obj_request->offset,
1642 NULL, snap_id, NULL);
1645 static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request)
1647 struct rbd_img_request *img_request = obj_request->img_request;
1648 struct ceph_osd_request *osd_req = obj_request->osd_req;
1649 struct ceph_snap_context *snapc;
1650 struct timespec mtime = CURRENT_TIME;
1652 rbd_assert(osd_req != NULL);
1654 snapc = img_request ? img_request->snapc : NULL;
1655 ceph_osdc_build_request(osd_req, obj_request->offset,
1656 snapc, CEPH_NOSNAP, &mtime);
1659 static struct ceph_osd_request *rbd_osd_req_create(
1660 struct rbd_device *rbd_dev,
1662 struct rbd_obj_request *obj_request)
1664 struct ceph_snap_context *snapc = NULL;
1665 struct ceph_osd_client *osdc;
1666 struct ceph_osd_request *osd_req;
1668 if (obj_request_img_data_test(obj_request)) {
1669 struct rbd_img_request *img_request = obj_request->img_request;
1671 rbd_assert(write_request ==
1672 img_request_write_test(img_request));
1674 snapc = img_request->snapc;
1677 /* Allocate and initialize the request, for the single op */
1679 osdc = &rbd_dev->rbd_client->client->osdc;
1680 osd_req = ceph_osdc_alloc_request(osdc, snapc, 1, false, GFP_ATOMIC);
1682 return NULL; /* ENOMEM */
1685 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1687 osd_req->r_flags = CEPH_OSD_FLAG_READ;
1689 osd_req->r_callback = rbd_osd_req_callback;
1690 osd_req->r_priv = obj_request;
1692 osd_req->r_oid_len = strlen(obj_request->object_name);
1693 rbd_assert(osd_req->r_oid_len < sizeof (osd_req->r_oid));
1694 memcpy(osd_req->r_oid, obj_request->object_name, osd_req->r_oid_len);
1696 osd_req->r_file_layout = rbd_dev->layout; /* struct */
1702 * Create a copyup osd request based on the information in the
1703 * object request supplied. A copyup request has two osd ops,
1704 * a copyup method call, and a "normal" write request.
1706 static struct ceph_osd_request *
1707 rbd_osd_req_create_copyup(struct rbd_obj_request *obj_request)
1709 struct rbd_img_request *img_request;
1710 struct ceph_snap_context *snapc;
1711 struct rbd_device *rbd_dev;
1712 struct ceph_osd_client *osdc;
1713 struct ceph_osd_request *osd_req;
1715 rbd_assert(obj_request_img_data_test(obj_request));
1716 img_request = obj_request->img_request;
1717 rbd_assert(img_request);
1718 rbd_assert(img_request_write_test(img_request));
1720 /* Allocate and initialize the request, for the two ops */
1722 snapc = img_request->snapc;
1723 rbd_dev = img_request->rbd_dev;
1724 osdc = &rbd_dev->rbd_client->client->osdc;
1725 osd_req = ceph_osdc_alloc_request(osdc, snapc, 2, false, GFP_ATOMIC);
1727 return NULL; /* ENOMEM */
1729 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1730 osd_req->r_callback = rbd_osd_req_callback;
1731 osd_req->r_priv = obj_request;
1733 osd_req->r_oid_len = strlen(obj_request->object_name);
1734 rbd_assert(osd_req->r_oid_len < sizeof (osd_req->r_oid));
1735 memcpy(osd_req->r_oid, obj_request->object_name, osd_req->r_oid_len);
1737 osd_req->r_file_layout = rbd_dev->layout; /* struct */
1743 static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req)
1745 ceph_osdc_put_request(osd_req);
1748 /* object_name is assumed to be a non-null pointer and NUL-terminated */
1750 static struct rbd_obj_request *rbd_obj_request_create(const char *object_name,
1751 u64 offset, u64 length,
1752 enum obj_request_type type)
1754 struct rbd_obj_request *obj_request;
1758 rbd_assert(obj_request_type_valid(type));
1760 size = strlen(object_name) + 1;
1761 name = kmalloc(size, GFP_KERNEL);
1765 obj_request = kzalloc(sizeof (*obj_request), GFP_KERNEL);
1771 obj_request->object_name = memcpy(name, object_name, size);
1772 obj_request->offset = offset;
1773 obj_request->length = length;
1774 obj_request->flags = 0;
1775 obj_request->which = BAD_WHICH;
1776 obj_request->type = type;
1777 INIT_LIST_HEAD(&obj_request->links);
1778 init_completion(&obj_request->completion);
1779 kref_init(&obj_request->kref);
1781 dout("%s: \"%s\" %llu/%llu %d -> obj %p\n", __func__, object_name,
1782 offset, length, (int)type, obj_request);
1787 static void rbd_obj_request_destroy(struct kref *kref)
1789 struct rbd_obj_request *obj_request;
1791 obj_request = container_of(kref, struct rbd_obj_request, kref);
1793 dout("%s: obj %p\n", __func__, obj_request);
1795 rbd_assert(obj_request->img_request == NULL);
1796 rbd_assert(obj_request->which == BAD_WHICH);
1798 if (obj_request->osd_req)
1799 rbd_osd_req_destroy(obj_request->osd_req);
1801 rbd_assert(obj_request_type_valid(obj_request->type));
1802 switch (obj_request->type) {
1803 case OBJ_REQUEST_NODATA:
1804 break; /* Nothing to do */
1805 case OBJ_REQUEST_BIO:
1806 if (obj_request->bio_list)
1807 bio_chain_put(obj_request->bio_list);
1809 case OBJ_REQUEST_PAGES:
1810 if (obj_request->pages)
1811 ceph_release_page_vector(obj_request->pages,
1812 obj_request->page_count);
1816 kfree(obj_request->object_name);
1821 * Caller is responsible for filling in the list of object requests
1822 * that comprises the image request, and the Linux request pointer
1823 * (if there is one).
1825 static struct rbd_img_request *rbd_img_request_create(
1826 struct rbd_device *rbd_dev,
1827 u64 offset, u64 length,
1831 struct rbd_img_request *img_request;
1833 img_request = kmem_cache_alloc(rbd_img_request_cache, GFP_ATOMIC);
1837 if (write_request) {
1838 down_read(&rbd_dev->header_rwsem);
1839 ceph_get_snap_context(rbd_dev->header.snapc);
1840 up_read(&rbd_dev->header_rwsem);
1843 img_request->rq = NULL;
1844 img_request->rbd_dev = rbd_dev;
1845 img_request->offset = offset;
1846 img_request->length = length;
1847 img_request->flags = 0;
1848 if (write_request) {
1849 img_request_write_set(img_request);
1850 img_request->snapc = rbd_dev->header.snapc;
1852 img_request->snap_id = rbd_dev->spec->snap_id;
1855 img_request_child_set(img_request);
1856 if (rbd_dev->parent_spec)
1857 img_request_layered_set(img_request);
1858 spin_lock_init(&img_request->completion_lock);
1859 img_request->next_completion = 0;
1860 img_request->callback = NULL;
1861 img_request->result = 0;
1862 img_request->obj_request_count = 0;
1863 INIT_LIST_HEAD(&img_request->obj_requests);
1864 kref_init(&img_request->kref);
1866 rbd_img_request_get(img_request); /* Avoid a warning */
1867 rbd_img_request_put(img_request); /* TEMPORARY */
1869 dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev,
1870 write_request ? "write" : "read", offset, length,
1876 static void rbd_img_request_destroy(struct kref *kref)
1878 struct rbd_img_request *img_request;
1879 struct rbd_obj_request *obj_request;
1880 struct rbd_obj_request *next_obj_request;
1882 img_request = container_of(kref, struct rbd_img_request, kref);
1884 dout("%s: img %p\n", __func__, img_request);
1886 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
1887 rbd_img_obj_request_del(img_request, obj_request);
1888 rbd_assert(img_request->obj_request_count == 0);
1890 if (img_request_write_test(img_request))
1891 ceph_put_snap_context(img_request->snapc);
1893 if (img_request_child_test(img_request))
1894 rbd_obj_request_put(img_request->obj_request);
1896 kmem_cache_free(rbd_img_request_cache, img_request);
1899 static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request)
1901 struct rbd_img_request *img_request;
1902 unsigned int xferred;
1906 rbd_assert(obj_request_img_data_test(obj_request));
1907 img_request = obj_request->img_request;
1909 rbd_assert(obj_request->xferred <= (u64)UINT_MAX);
1910 xferred = (unsigned int)obj_request->xferred;
1911 result = obj_request->result;
1913 struct rbd_device *rbd_dev = img_request->rbd_dev;
1915 rbd_warn(rbd_dev, "%s %llx at %llx (%llx)\n",
1916 img_request_write_test(img_request) ? "write" : "read",
1917 obj_request->length, obj_request->img_offset,
1918 obj_request->offset);
1919 rbd_warn(rbd_dev, " result %d xferred %x\n",
1921 if (!img_request->result)
1922 img_request->result = result;
1925 /* Image object requests don't own their page array */
1927 if (obj_request->type == OBJ_REQUEST_PAGES) {
1928 obj_request->pages = NULL;
1929 obj_request->page_count = 0;
1932 if (img_request_child_test(img_request)) {
1933 rbd_assert(img_request->obj_request != NULL);
1934 more = obj_request->which < img_request->obj_request_count - 1;
1936 rbd_assert(img_request->rq != NULL);
1937 more = blk_end_request(img_request->rq, result, xferred);
1943 static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
1945 struct rbd_img_request *img_request;
1946 u32 which = obj_request->which;
1949 rbd_assert(obj_request_img_data_test(obj_request));
1950 img_request = obj_request->img_request;
1952 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
1953 rbd_assert(img_request != NULL);
1954 rbd_assert(img_request->obj_request_count > 0);
1955 rbd_assert(which != BAD_WHICH);
1956 rbd_assert(which < img_request->obj_request_count);
1957 rbd_assert(which >= img_request->next_completion);
1959 spin_lock_irq(&img_request->completion_lock);
1960 if (which != img_request->next_completion)
1963 for_each_obj_request_from(img_request, obj_request) {
1965 rbd_assert(which < img_request->obj_request_count);
1967 if (!obj_request_done_test(obj_request))
1969 more = rbd_img_obj_end_request(obj_request);
1973 rbd_assert(more ^ (which == img_request->obj_request_count));
1974 img_request->next_completion = which;
1976 spin_unlock_irq(&img_request->completion_lock);
1979 rbd_img_request_complete(img_request);
1983 * Split up an image request into one or more object requests, each
1984 * to a different object. The "type" parameter indicates whether
1985 * "data_desc" is the pointer to the head of a list of bio
1986 * structures, or the base of a page array. In either case this
1987 * function assumes data_desc describes memory sufficient to hold
1988 * all data described by the image request.
1990 static int rbd_img_request_fill(struct rbd_img_request *img_request,
1991 enum obj_request_type type,
1994 struct rbd_device *rbd_dev = img_request->rbd_dev;
1995 struct rbd_obj_request *obj_request = NULL;
1996 struct rbd_obj_request *next_obj_request;
1997 bool write_request = img_request_write_test(img_request);
1998 struct bio *bio_list;
1999 unsigned int bio_offset = 0;
2000 struct page **pages;
2005 dout("%s: img %p type %d data_desc %p\n", __func__, img_request,
2006 (int)type, data_desc);
2008 opcode = write_request ? CEPH_OSD_OP_WRITE : CEPH_OSD_OP_READ;
2009 img_offset = img_request->offset;
2010 resid = img_request->length;
2011 rbd_assert(resid > 0);
2013 if (type == OBJ_REQUEST_BIO) {
2014 bio_list = data_desc;
2015 rbd_assert(img_offset == bio_list->bi_sector << SECTOR_SHIFT);
2017 rbd_assert(type == OBJ_REQUEST_PAGES);
2022 struct ceph_osd_request *osd_req;
2023 const char *object_name;
2027 object_name = rbd_segment_name(rbd_dev, img_offset);
2030 offset = rbd_segment_offset(rbd_dev, img_offset);
2031 length = rbd_segment_length(rbd_dev, img_offset, resid);
2032 obj_request = rbd_obj_request_create(object_name,
2033 offset, length, type);
2034 kfree(object_name); /* object request has its own copy */
2038 if (type == OBJ_REQUEST_BIO) {
2039 unsigned int clone_size;
2041 rbd_assert(length <= (u64)UINT_MAX);
2042 clone_size = (unsigned int)length;
2043 obj_request->bio_list =
2044 bio_chain_clone_range(&bio_list,
2048 if (!obj_request->bio_list)
2051 unsigned int page_count;
2053 obj_request->pages = pages;
2054 page_count = (u32)calc_pages_for(offset, length);
2055 obj_request->page_count = page_count;
2056 if ((offset + length) & ~PAGE_MASK)
2057 page_count--; /* more on last page */
2058 pages += page_count;
2061 osd_req = rbd_osd_req_create(rbd_dev, write_request,
2065 obj_request->osd_req = osd_req;
2066 obj_request->callback = rbd_img_obj_callback;
2068 osd_req_op_extent_init(osd_req, 0, opcode, offset, length,
2070 if (type == OBJ_REQUEST_BIO)
2071 osd_req_op_extent_osd_data_bio(osd_req, 0,
2072 obj_request->bio_list, length);
2074 osd_req_op_extent_osd_data_pages(osd_req, 0,
2075 obj_request->pages, length,
2076 offset & ~PAGE_MASK, false, false);
2079 rbd_osd_req_format_write(obj_request);
2081 rbd_osd_req_format_read(obj_request);
2083 obj_request->img_offset = img_offset;
2084 rbd_img_obj_request_add(img_request, obj_request);
2086 img_offset += length;
2093 rbd_obj_request_put(obj_request);
2095 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2096 rbd_obj_request_put(obj_request);
2102 rbd_img_obj_copyup_callback(struct rbd_obj_request *obj_request)
2104 struct rbd_img_request *img_request;
2105 struct rbd_device *rbd_dev;
2109 rbd_assert(obj_request->type == OBJ_REQUEST_BIO);
2110 rbd_assert(obj_request_img_data_test(obj_request));
2111 img_request = obj_request->img_request;
2112 rbd_assert(img_request);
2114 rbd_dev = img_request->rbd_dev;
2115 rbd_assert(rbd_dev);
2116 length = (u64)1 << rbd_dev->header.obj_order;
2117 page_count = (u32)calc_pages_for(0, length);
2119 rbd_assert(obj_request->copyup_pages);
2120 ceph_release_page_vector(obj_request->copyup_pages, page_count);
2121 obj_request->copyup_pages = NULL;
2124 * We want the transfer count to reflect the size of the
2125 * original write request. There is no such thing as a
2126 * successful short write, so if the request was successful
2127 * we can just set it to the originally-requested length.
2129 if (!obj_request->result)
2130 obj_request->xferred = obj_request->length;
2132 /* Finish up with the normal image object callback */
2134 rbd_img_obj_callback(obj_request);
2138 rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request)
2140 struct rbd_obj_request *orig_request;
2141 struct ceph_osd_request *osd_req;
2142 struct ceph_osd_client *osdc;
2143 struct rbd_device *rbd_dev;
2144 struct page **pages;
2149 rbd_assert(img_request_child_test(img_request));
2151 /* First get what we need from the image request */
2153 pages = img_request->copyup_pages;
2154 rbd_assert(pages != NULL);
2155 img_request->copyup_pages = NULL;
2157 orig_request = img_request->obj_request;
2158 rbd_assert(orig_request != NULL);
2159 rbd_assert(orig_request->type == OBJ_REQUEST_BIO);
2160 result = img_request->result;
2161 obj_size = img_request->length;
2162 xferred = img_request->xferred;
2164 rbd_dev = img_request->rbd_dev;
2165 rbd_assert(rbd_dev);
2166 rbd_assert(obj_size == (u64)1 << rbd_dev->header.obj_order);
2168 rbd_img_request_put(img_request);
2173 /* Allocate the new copyup osd request for the original request */
2176 rbd_assert(!orig_request->osd_req);
2177 osd_req = rbd_osd_req_create_copyup(orig_request);
2180 orig_request->osd_req = osd_req;
2181 orig_request->copyup_pages = pages;
2183 /* Initialize the copyup op */
2185 osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup");
2186 osd_req_op_cls_request_data_pages(osd_req, 0, pages, obj_size, 0,
2189 /* Then the original write request op */
2191 osd_req_op_extent_init(osd_req, 1, CEPH_OSD_OP_WRITE,
2192 orig_request->offset,
2193 orig_request->length, 0, 0);
2194 osd_req_op_extent_osd_data_bio(osd_req, 1, orig_request->bio_list,
2195 orig_request->length);
2197 rbd_osd_req_format_write(orig_request);
2199 /* All set, send it off. */
2201 orig_request->callback = rbd_img_obj_copyup_callback;
2202 osdc = &rbd_dev->rbd_client->client->osdc;
2203 result = rbd_obj_request_submit(osdc, orig_request);
2207 /* Record the error code and complete the request */
2209 orig_request->result = result;
2210 orig_request->xferred = 0;
2211 obj_request_done_set(orig_request);
2212 rbd_obj_request_complete(orig_request);
2216 * Read from the parent image the range of data that covers the
2217 * entire target of the given object request. This is used for
2218 * satisfying a layered image write request when the target of an
2219 * object request from the image request does not exist.
2221 * A page array big enough to hold the returned data is allocated
2222 * and supplied to rbd_img_request_fill() as the "data descriptor."
2223 * When the read completes, this page array will be transferred to
2224 * the original object request for the copyup operation.
2226 * If an error occurs, record it as the result of the original
2227 * object request and mark it done so it gets completed.
2229 static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request)
2231 struct rbd_img_request *img_request = NULL;
2232 struct rbd_img_request *parent_request = NULL;
2233 struct rbd_device *rbd_dev;
2236 struct page **pages = NULL;
2240 rbd_assert(obj_request_img_data_test(obj_request));
2241 rbd_assert(obj_request->type == OBJ_REQUEST_BIO);
2243 img_request = obj_request->img_request;
2244 rbd_assert(img_request != NULL);
2245 rbd_dev = img_request->rbd_dev;
2246 rbd_assert(rbd_dev->parent != NULL);
2249 * First things first. The original osd request is of no
2250 * use to use any more, we'll need a new one that can hold
2251 * the two ops in a copyup request. We'll get that later,
2252 * but for now we can release the old one.
2254 rbd_osd_req_destroy(obj_request->osd_req);
2255 obj_request->osd_req = NULL;
2258 * Determine the byte range covered by the object in the
2259 * child image to which the original request was to be sent.
2261 img_offset = obj_request->img_offset - obj_request->offset;
2262 length = (u64)1 << rbd_dev->header.obj_order;
2265 * There is no defined parent data beyond the parent
2266 * overlap, so limit what we read at that boundary if
2269 if (img_offset + length > rbd_dev->parent_overlap) {
2270 rbd_assert(img_offset < rbd_dev->parent_overlap);
2271 length = rbd_dev->parent_overlap - img_offset;
2275 * Allocate a page array big enough to receive the data read
2278 page_count = (u32)calc_pages_for(0, length);
2279 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2280 if (IS_ERR(pages)) {
2281 result = PTR_ERR(pages);
2287 parent_request = rbd_img_request_create(rbd_dev->parent,
2290 if (!parent_request)
2292 rbd_obj_request_get(obj_request);
2293 parent_request->obj_request = obj_request;
2295 result = rbd_img_request_fill(parent_request, OBJ_REQUEST_PAGES, pages);
2298 parent_request->copyup_pages = pages;
2300 parent_request->callback = rbd_img_obj_parent_read_full_callback;
2301 result = rbd_img_request_submit(parent_request);
2305 parent_request->copyup_pages = NULL;
2306 parent_request->obj_request = NULL;
2307 rbd_obj_request_put(obj_request);
2310 ceph_release_page_vector(pages, page_count);
2312 rbd_img_request_put(parent_request);
2313 obj_request->result = result;
2314 obj_request->xferred = 0;
2315 obj_request_done_set(obj_request);
2320 static void rbd_img_obj_exists_callback(struct rbd_obj_request *obj_request)
2322 struct rbd_obj_request *orig_request;
2325 rbd_assert(!obj_request_img_data_test(obj_request));
2328 * All we need from the object request is the original
2329 * request and the result of the STAT op. Grab those, then
2330 * we're done with the request.
2332 orig_request = obj_request->obj_request;
2333 obj_request->obj_request = NULL;
2334 rbd_assert(orig_request);
2335 rbd_assert(orig_request->img_request);
2337 result = obj_request->result;
2338 obj_request->result = 0;
2340 dout("%s: obj %p for obj %p result %d %llu/%llu\n", __func__,
2341 obj_request, orig_request, result,
2342 obj_request->xferred, obj_request->length);
2343 rbd_obj_request_put(obj_request);
2345 rbd_assert(orig_request);
2346 rbd_assert(orig_request->img_request);
2349 * Our only purpose here is to determine whether the object
2350 * exists, and we don't want to treat the non-existence as
2351 * an error. If something else comes back, transfer the
2352 * error to the original request and complete it now.
2355 obj_request_existence_set(orig_request, true);
2356 } else if (result == -ENOENT) {
2357 obj_request_existence_set(orig_request, false);
2358 } else if (result) {
2359 orig_request->result = result;
2364 * Resubmit the original request now that we have recorded
2365 * whether the target object exists.
2367 orig_request->result = rbd_img_obj_request_submit(orig_request);
2369 if (orig_request->result)
2370 rbd_obj_request_complete(orig_request);
2371 rbd_obj_request_put(orig_request);
2374 static int rbd_img_obj_exists_submit(struct rbd_obj_request *obj_request)
2376 struct rbd_obj_request *stat_request;
2377 struct rbd_device *rbd_dev;
2378 struct ceph_osd_client *osdc;
2379 struct page **pages = NULL;
2385 * The response data for a STAT call consists of:
2392 size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32);
2393 page_count = (u32)calc_pages_for(0, size);
2394 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2396 return PTR_ERR(pages);
2399 stat_request = rbd_obj_request_create(obj_request->object_name, 0, 0,
2404 rbd_obj_request_get(obj_request);
2405 stat_request->obj_request = obj_request;
2406 stat_request->pages = pages;
2407 stat_request->page_count = page_count;
2409 rbd_assert(obj_request->img_request);
2410 rbd_dev = obj_request->img_request->rbd_dev;
2411 stat_request->osd_req = rbd_osd_req_create(rbd_dev, false,
2413 if (!stat_request->osd_req)
2415 stat_request->callback = rbd_img_obj_exists_callback;
2417 osd_req_op_init(stat_request->osd_req, 0, CEPH_OSD_OP_STAT);
2418 osd_req_op_raw_data_in_pages(stat_request->osd_req, 0, pages, size, 0,
2420 rbd_osd_req_format_read(stat_request);
2422 osdc = &rbd_dev->rbd_client->client->osdc;
2423 ret = rbd_obj_request_submit(osdc, stat_request);
2426 rbd_obj_request_put(obj_request);
2431 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request)
2433 struct rbd_img_request *img_request;
2434 struct rbd_device *rbd_dev;
2437 rbd_assert(obj_request_img_data_test(obj_request));
2439 img_request = obj_request->img_request;
2440 rbd_assert(img_request);
2441 rbd_dev = img_request->rbd_dev;
2444 * Only writes to layered images need special handling.
2445 * Reads and non-layered writes are simple object requests.
2446 * Layered writes that start beyond the end of the overlap
2447 * with the parent have no parent data, so they too are
2448 * simple object requests. Finally, if the target object is
2449 * known to already exist, its parent data has already been
2450 * copied, so a write to the object can also be handled as a
2451 * simple object request.
2453 if (!img_request_write_test(img_request) ||
2454 !img_request_layered_test(img_request) ||
2455 rbd_dev->parent_overlap <= obj_request->img_offset ||
2456 ((known = obj_request_known_test(obj_request)) &&
2457 obj_request_exists_test(obj_request))) {
2459 struct rbd_device *rbd_dev;
2460 struct ceph_osd_client *osdc;
2462 rbd_dev = obj_request->img_request->rbd_dev;
2463 osdc = &rbd_dev->rbd_client->client->osdc;
2465 return rbd_obj_request_submit(osdc, obj_request);
2469 * It's a layered write. The target object might exist but
2470 * we may not know that yet. If we know it doesn't exist,
2471 * start by reading the data for the full target object from
2472 * the parent so we can use it for a copyup to the target.
2475 return rbd_img_obj_parent_read_full(obj_request);
2477 /* We don't know whether the target exists. Go find out. */
2479 return rbd_img_obj_exists_submit(obj_request);
2482 static int rbd_img_request_submit(struct rbd_img_request *img_request)
2484 struct rbd_obj_request *obj_request;
2485 struct rbd_obj_request *next_obj_request;
2487 dout("%s: img %p\n", __func__, img_request);
2488 for_each_obj_request_safe(img_request, obj_request, next_obj_request) {
2491 ret = rbd_img_obj_request_submit(obj_request);
2499 static void rbd_img_parent_read_callback(struct rbd_img_request *img_request)
2501 struct rbd_obj_request *obj_request;
2502 struct rbd_device *rbd_dev;
2505 rbd_assert(img_request_child_test(img_request));
2507 obj_request = img_request->obj_request;
2508 rbd_assert(obj_request);
2509 rbd_assert(obj_request->img_request);
2511 obj_request->result = img_request->result;
2512 if (obj_request->result)
2516 * We need to zero anything beyond the parent overlap
2517 * boundary. Since rbd_img_obj_request_read_callback()
2518 * will zero anything beyond the end of a short read, an
2519 * easy way to do this is to pretend the data from the
2520 * parent came up short--ending at the overlap boundary.
2522 rbd_assert(obj_request->img_offset < U64_MAX - obj_request->length);
2523 obj_end = obj_request->img_offset + obj_request->length;
2524 rbd_dev = obj_request->img_request->rbd_dev;
2525 if (obj_end > rbd_dev->parent_overlap) {
2528 if (obj_request->img_offset < rbd_dev->parent_overlap)
2529 xferred = rbd_dev->parent_overlap -
2530 obj_request->img_offset;
2532 obj_request->xferred = min(img_request->xferred, xferred);
2534 obj_request->xferred = img_request->xferred;
2537 rbd_img_obj_request_read_callback(obj_request);
2538 rbd_obj_request_complete(obj_request);
2541 static void rbd_img_parent_read(struct rbd_obj_request *obj_request)
2543 struct rbd_device *rbd_dev;
2544 struct rbd_img_request *img_request;
2547 rbd_assert(obj_request_img_data_test(obj_request));
2548 rbd_assert(obj_request->img_request != NULL);
2549 rbd_assert(obj_request->result == (s32) -ENOENT);
2550 rbd_assert(obj_request->type == OBJ_REQUEST_BIO);
2552 rbd_dev = obj_request->img_request->rbd_dev;
2553 rbd_assert(rbd_dev->parent != NULL);
2554 /* rbd_read_finish(obj_request, obj_request->length); */
2555 img_request = rbd_img_request_create(rbd_dev->parent,
2556 obj_request->img_offset,
2557 obj_request->length,
2563 rbd_obj_request_get(obj_request);
2564 img_request->obj_request = obj_request;
2566 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
2567 obj_request->bio_list);
2571 img_request->callback = rbd_img_parent_read_callback;
2572 result = rbd_img_request_submit(img_request);
2579 rbd_img_request_put(img_request);
2580 obj_request->result = result;
2581 obj_request->xferred = 0;
2582 obj_request_done_set(obj_request);
2585 static int rbd_obj_notify_ack(struct rbd_device *rbd_dev, u64 notify_id)
2587 struct rbd_obj_request *obj_request;
2588 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2591 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
2592 OBJ_REQUEST_NODATA);
2597 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
2598 if (!obj_request->osd_req)
2600 obj_request->callback = rbd_obj_request_put;
2602 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK,
2604 rbd_osd_req_format_read(obj_request);
2606 ret = rbd_obj_request_submit(osdc, obj_request);
2609 rbd_obj_request_put(obj_request);
2614 static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
2616 struct rbd_device *rbd_dev = (struct rbd_device *)data;
2621 dout("%s: \"%s\" notify_id %llu opcode %u\n", __func__,
2622 rbd_dev->header_name, (unsigned long long)notify_id,
2623 (unsigned int)opcode);
2624 (void)rbd_dev_refresh(rbd_dev);
2626 rbd_obj_notify_ack(rbd_dev, notify_id);
2630 * Request sync osd watch/unwatch. The value of "start" determines
2631 * whether a watch request is being initiated or torn down.
2633 static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, int start)
2635 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2636 struct rbd_obj_request *obj_request;
2639 rbd_assert(start ^ !!rbd_dev->watch_event);
2640 rbd_assert(start ^ !!rbd_dev->watch_request);
2643 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
2644 &rbd_dev->watch_event);
2647 rbd_assert(rbd_dev->watch_event != NULL);
2651 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
2652 OBJ_REQUEST_NODATA);
2656 obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, obj_request);
2657 if (!obj_request->osd_req)
2661 ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
2663 ceph_osdc_unregister_linger_request(osdc,
2664 rbd_dev->watch_request->osd_req);
2666 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
2667 rbd_dev->watch_event->cookie, 0, start);
2668 rbd_osd_req_format_write(obj_request);
2670 ret = rbd_obj_request_submit(osdc, obj_request);
2673 ret = rbd_obj_request_wait(obj_request);
2676 ret = obj_request->result;
2681 * A watch request is set to linger, so the underlying osd
2682 * request won't go away until we unregister it. We retain
2683 * a pointer to the object request during that time (in
2684 * rbd_dev->watch_request), so we'll keep a reference to
2685 * it. We'll drop that reference (below) after we've
2689 rbd_dev->watch_request = obj_request;
2694 /* We have successfully torn down the watch request */
2696 rbd_obj_request_put(rbd_dev->watch_request);
2697 rbd_dev->watch_request = NULL;
2699 /* Cancel the event if we're tearing down, or on error */
2700 ceph_osdc_cancel_event(rbd_dev->watch_event);
2701 rbd_dev->watch_event = NULL;
2703 rbd_obj_request_put(obj_request);
2709 * Synchronous osd object method call. Returns the number of bytes
2710 * returned in the outbound buffer, or a negative error code.
2712 static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
2713 const char *object_name,
2714 const char *class_name,
2715 const char *method_name,
2716 const void *outbound,
2717 size_t outbound_size,
2719 size_t inbound_size)
2721 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2722 struct rbd_obj_request *obj_request;
2723 struct page **pages;
2728 * Method calls are ultimately read operations. The result
2729 * should placed into the inbound buffer provided. They
2730 * also supply outbound data--parameters for the object
2731 * method. Currently if this is present it will be a
2734 page_count = (u32)calc_pages_for(0, inbound_size);
2735 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2737 return PTR_ERR(pages);
2740 obj_request = rbd_obj_request_create(object_name, 0, inbound_size,
2745 obj_request->pages = pages;
2746 obj_request->page_count = page_count;
2748 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
2749 if (!obj_request->osd_req)
2752 osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL,
2753 class_name, method_name);
2754 if (outbound_size) {
2755 struct ceph_pagelist *pagelist;
2757 pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS);
2761 ceph_pagelist_init(pagelist);
2762 ceph_pagelist_append(pagelist, outbound, outbound_size);
2763 osd_req_op_cls_request_data_pagelist(obj_request->osd_req, 0,
2766 osd_req_op_cls_response_data_pages(obj_request->osd_req, 0,
2767 obj_request->pages, inbound_size,
2769 rbd_osd_req_format_read(obj_request);
2771 ret = rbd_obj_request_submit(osdc, obj_request);
2774 ret = rbd_obj_request_wait(obj_request);
2778 ret = obj_request->result;
2782 rbd_assert(obj_request->xferred < (u64)INT_MAX);
2783 ret = (int)obj_request->xferred;
2784 ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred);
2787 rbd_obj_request_put(obj_request);
2789 ceph_release_page_vector(pages, page_count);
2794 static void rbd_request_fn(struct request_queue *q)
2795 __releases(q->queue_lock) __acquires(q->queue_lock)
2797 struct rbd_device *rbd_dev = q->queuedata;
2798 bool read_only = rbd_dev->mapping.read_only;
2802 while ((rq = blk_fetch_request(q))) {
2803 bool write_request = rq_data_dir(rq) == WRITE;
2804 struct rbd_img_request *img_request;
2808 /* Ignore any non-FS requests that filter through. */
2810 if (rq->cmd_type != REQ_TYPE_FS) {
2811 dout("%s: non-fs request type %d\n", __func__,
2812 (int) rq->cmd_type);
2813 __blk_end_request_all(rq, 0);
2817 /* Ignore/skip any zero-length requests */
2819 offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT;
2820 length = (u64) blk_rq_bytes(rq);
2823 dout("%s: zero-length request\n", __func__);
2824 __blk_end_request_all(rq, 0);
2828 spin_unlock_irq(q->queue_lock);
2830 /* Disallow writes to a read-only device */
2832 if (write_request) {
2836 rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP);
2840 * Quit early if the mapped snapshot no longer
2841 * exists. It's still possible the snapshot will
2842 * have disappeared by the time our request arrives
2843 * at the osd, but there's no sense in sending it if
2846 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) {
2847 dout("request for non-existent snapshot");
2848 rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP);
2854 if (offset && length > U64_MAX - offset + 1) {
2855 rbd_warn(rbd_dev, "bad request range (%llu~%llu)\n",
2857 goto end_request; /* Shouldn't happen */
2861 img_request = rbd_img_request_create(rbd_dev, offset, length,
2862 write_request, false);
2866 img_request->rq = rq;
2868 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
2871 result = rbd_img_request_submit(img_request);
2873 rbd_img_request_put(img_request);
2875 spin_lock_irq(q->queue_lock);
2877 rbd_warn(rbd_dev, "%s %llx at %llx result %d\n",
2878 write_request ? "write" : "read",
2879 length, offset, result);
2881 __blk_end_request_all(rq, result);
2887 * a queue callback. Makes sure that we don't create a bio that spans across
2888 * multiple osd objects. One exception would be with a single page bios,
2889 * which we handle later at bio_chain_clone_range()
2891 static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2892 struct bio_vec *bvec)
2894 struct rbd_device *rbd_dev = q->queuedata;
2895 sector_t sector_offset;
2896 sector_t sectors_per_obj;
2897 sector_t obj_sector_offset;
2901 * Find how far into its rbd object the partition-relative
2902 * bio start sector is to offset relative to the enclosing
2905 sector_offset = get_start_sect(bmd->bi_bdev) + bmd->bi_sector;
2906 sectors_per_obj = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT);
2907 obj_sector_offset = sector_offset & (sectors_per_obj - 1);
2910 * Compute the number of bytes from that offset to the end
2911 * of the object. Account for what's already used by the bio.
2913 ret = (int) (sectors_per_obj - obj_sector_offset) << SECTOR_SHIFT;
2914 if (ret > bmd->bi_size)
2915 ret -= bmd->bi_size;
2920 * Don't send back more than was asked for. And if the bio
2921 * was empty, let the whole thing through because: "Note
2922 * that a block device *must* allow a single page to be
2923 * added to an empty bio."
2925 rbd_assert(bvec->bv_len <= PAGE_SIZE);
2926 if (ret > (int) bvec->bv_len || !bmd->bi_size)
2927 ret = (int) bvec->bv_len;
2932 static void rbd_free_disk(struct rbd_device *rbd_dev)
2934 struct gendisk *disk = rbd_dev->disk;
2939 rbd_dev->disk = NULL;
2940 if (disk->flags & GENHD_FL_UP) {
2943 blk_cleanup_queue(disk->queue);
2948 static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
2949 const char *object_name,
2950 u64 offset, u64 length, void *buf)
2953 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2954 struct rbd_obj_request *obj_request;
2955 struct page **pages = NULL;
2960 page_count = (u32) calc_pages_for(offset, length);
2961 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2963 ret = PTR_ERR(pages);
2966 obj_request = rbd_obj_request_create(object_name, offset, length,
2971 obj_request->pages = pages;
2972 obj_request->page_count = page_count;
2974 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, obj_request);
2975 if (!obj_request->osd_req)
2978 osd_req_op_extent_init(obj_request->osd_req, 0, CEPH_OSD_OP_READ,
2979 offset, length, 0, 0);
2980 osd_req_op_extent_osd_data_pages(obj_request->osd_req, 0,
2982 obj_request->length,
2983 obj_request->offset & ~PAGE_MASK,
2985 rbd_osd_req_format_read(obj_request);
2987 ret = rbd_obj_request_submit(osdc, obj_request);
2990 ret = rbd_obj_request_wait(obj_request);
2994 ret = obj_request->result;
2998 rbd_assert(obj_request->xferred <= (u64) SIZE_MAX);
2999 size = (size_t) obj_request->xferred;
3000 ceph_copy_from_page_vector(pages, buf, 0, size);
3001 rbd_assert(size <= (size_t)INT_MAX);
3005 rbd_obj_request_put(obj_request);
3007 ceph_release_page_vector(pages, page_count);
3013 * Read the complete header for the given rbd device.
3015 * Returns a pointer to a dynamically-allocated buffer containing
3016 * the complete and validated header. Caller can pass the address
3017 * of a variable that will be filled in with the version of the
3018 * header object at the time it was read.
3020 * Returns a pointer-coded errno if a failure occurs.
3022 static struct rbd_image_header_ondisk *
3023 rbd_dev_v1_header_read(struct rbd_device *rbd_dev)
3025 struct rbd_image_header_ondisk *ondisk = NULL;
3032 * The complete header will include an array of its 64-bit
3033 * snapshot ids, followed by the names of those snapshots as
3034 * a contiguous block of NUL-terminated strings. Note that
3035 * the number of snapshots could change by the time we read
3036 * it in, in which case we re-read it.
3043 size = sizeof (*ondisk);
3044 size += snap_count * sizeof (struct rbd_image_snap_ondisk);
3046 ondisk = kmalloc(size, GFP_KERNEL);
3048 return ERR_PTR(-ENOMEM);
3050 ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name,
3054 if ((size_t)ret < size) {
3056 rbd_warn(rbd_dev, "short header read (want %zd got %d)",
3060 if (!rbd_dev_ondisk_valid(ondisk)) {
3062 rbd_warn(rbd_dev, "invalid header");
3066 names_size = le64_to_cpu(ondisk->snap_names_len);
3067 want_count = snap_count;
3068 snap_count = le32_to_cpu(ondisk->snap_count);
3069 } while (snap_count != want_count);
3076 return ERR_PTR(ret);
3080 * reload the ondisk the header
3082 static int rbd_read_header(struct rbd_device *rbd_dev,
3083 struct rbd_image_header *header)
3085 struct rbd_image_header_ondisk *ondisk;
3088 ondisk = rbd_dev_v1_header_read(rbd_dev);
3090 return PTR_ERR(ondisk);
3091 ret = rbd_header_from_disk(header, ondisk);
3097 static void rbd_update_mapping_size(struct rbd_device *rbd_dev)
3099 if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
3102 if (rbd_dev->mapping.size != rbd_dev->header.image_size) {
3105 rbd_dev->mapping.size = rbd_dev->header.image_size;
3106 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
3107 dout("setting size to %llu sectors", (unsigned long long)size);
3108 set_capacity(rbd_dev->disk, size);
3113 * only read the first part of the ondisk header, without the snaps info
3115 static int rbd_dev_v1_refresh(struct rbd_device *rbd_dev)
3118 struct rbd_image_header h;
3120 ret = rbd_read_header(rbd_dev, &h);
3124 down_write(&rbd_dev->header_rwsem);
3126 /* Update image size, and check for resize of mapped image */
3127 rbd_dev->header.image_size = h.image_size;
3128 rbd_update_mapping_size(rbd_dev);
3130 /* rbd_dev->header.object_prefix shouldn't change */
3131 kfree(rbd_dev->header.snap_sizes);
3132 kfree(rbd_dev->header.snap_names);
3133 /* osd requests may still refer to snapc */
3134 ceph_put_snap_context(rbd_dev->header.snapc);
3136 rbd_dev->header.image_size = h.image_size;
3137 rbd_dev->header.snapc = h.snapc;
3138 rbd_dev->header.snap_names = h.snap_names;
3139 rbd_dev->header.snap_sizes = h.snap_sizes;
3140 /* Free the extra copy of the object prefix */
3141 if (strcmp(rbd_dev->header.object_prefix, h.object_prefix))
3142 rbd_warn(rbd_dev, "object prefix changed (ignoring)");
3143 kfree(h.object_prefix);
3145 up_write(&rbd_dev->header_rwsem);
3151 * Clear the rbd device's EXISTS flag if the snapshot it's mapped to
3152 * has disappeared from the (just updated) snapshot context.
3154 static void rbd_exists_validate(struct rbd_device *rbd_dev)
3158 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags))
3161 snap_id = rbd_dev->spec->snap_id;
3162 if (snap_id == CEPH_NOSNAP)
3165 if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX)
3166 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
3169 static int rbd_dev_refresh(struct rbd_device *rbd_dev)
3174 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
3175 image_size = rbd_dev->header.image_size;
3176 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
3177 if (rbd_dev->image_format == 1)
3178 ret = rbd_dev_v1_refresh(rbd_dev);
3180 ret = rbd_dev_v2_refresh(rbd_dev);
3182 /* If it's a mapped snapshot, validate its EXISTS flag */
3184 rbd_exists_validate(rbd_dev);
3185 mutex_unlock(&ctl_mutex);
3187 rbd_warn(rbd_dev, "got notification but failed to "
3188 " update snaps: %d\n", ret);
3189 if (image_size != rbd_dev->header.image_size)
3190 revalidate_disk(rbd_dev->disk);
3195 static int rbd_init_disk(struct rbd_device *rbd_dev)
3197 struct gendisk *disk;
3198 struct request_queue *q;
3201 /* create gendisk info */
3202 disk = alloc_disk(RBD_MINORS_PER_MAJOR);
3206 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
3208 disk->major = rbd_dev->major;
3209 disk->first_minor = 0;
3210 disk->fops = &rbd_bd_ops;
3211 disk->private_data = rbd_dev;
3213 q = blk_init_queue(rbd_request_fn, &rbd_dev->lock);
3217 /* We use the default size, but let's be explicit about it. */
3218 blk_queue_physical_block_size(q, SECTOR_SIZE);
3220 /* set io sizes to object size */
3221 segment_size = rbd_obj_bytes(&rbd_dev->header);
3222 blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
3223 blk_queue_max_segment_size(q, segment_size);
3224 blk_queue_io_min(q, segment_size);
3225 blk_queue_io_opt(q, segment_size);
3227 blk_queue_merge_bvec(q, rbd_merge_bvec);
3230 q->queuedata = rbd_dev;
3232 rbd_dev->disk = disk;
3245 static struct rbd_device *dev_to_rbd_dev(struct device *dev)
3247 return container_of(dev, struct rbd_device, dev);
3250 static ssize_t rbd_size_show(struct device *dev,
3251 struct device_attribute *attr, char *buf)
3253 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3255 return sprintf(buf, "%llu\n",
3256 (unsigned long long)rbd_dev->mapping.size);
3260 * Note this shows the features for whatever's mapped, which is not
3261 * necessarily the base image.
3263 static ssize_t rbd_features_show(struct device *dev,
3264 struct device_attribute *attr, char *buf)
3266 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3268 return sprintf(buf, "0x%016llx\n",
3269 (unsigned long long)rbd_dev->mapping.features);
3272 static ssize_t rbd_major_show(struct device *dev,
3273 struct device_attribute *attr, char *buf)
3275 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3278 return sprintf(buf, "%d\n", rbd_dev->major);
3280 return sprintf(buf, "(none)\n");
3284 static ssize_t rbd_client_id_show(struct device *dev,
3285 struct device_attribute *attr, char *buf)
3287 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3289 return sprintf(buf, "client%lld\n",
3290 ceph_client_id(rbd_dev->rbd_client->client));
3293 static ssize_t rbd_pool_show(struct device *dev,
3294 struct device_attribute *attr, char *buf)
3296 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3298 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
3301 static ssize_t rbd_pool_id_show(struct device *dev,
3302 struct device_attribute *attr, char *buf)
3304 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3306 return sprintf(buf, "%llu\n",
3307 (unsigned long long) rbd_dev->spec->pool_id);
3310 static ssize_t rbd_name_show(struct device *dev,
3311 struct device_attribute *attr, char *buf)
3313 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3315 if (rbd_dev->spec->image_name)
3316 return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
3318 return sprintf(buf, "(unknown)\n");
3321 static ssize_t rbd_image_id_show(struct device *dev,
3322 struct device_attribute *attr, char *buf)
3324 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3326 return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
3330 * Shows the name of the currently-mapped snapshot (or
3331 * RBD_SNAP_HEAD_NAME for the base image).
3333 static ssize_t rbd_snap_show(struct device *dev,
3334 struct device_attribute *attr,
3337 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3339 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
3343 * For an rbd v2 image, shows the pool id, image id, and snapshot id
3344 * for the parent image. If there is no parent, simply shows
3345 * "(no parent image)".
3347 static ssize_t rbd_parent_show(struct device *dev,
3348 struct device_attribute *attr,
3351 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3352 struct rbd_spec *spec = rbd_dev->parent_spec;
3357 return sprintf(buf, "(no parent image)\n");
3359 count = sprintf(bufp, "pool_id %llu\npool_name %s\n",
3360 (unsigned long long) spec->pool_id, spec->pool_name);
3365 count = sprintf(bufp, "image_id %s\nimage_name %s\n", spec->image_id,
3366 spec->image_name ? spec->image_name : "(unknown)");
3371 count = sprintf(bufp, "snap_id %llu\nsnap_name %s\n",
3372 (unsigned long long) spec->snap_id, spec->snap_name);
3377 count = sprintf(bufp, "overlap %llu\n", rbd_dev->parent_overlap);
3382 return (ssize_t) (bufp - buf);
3385 static ssize_t rbd_image_refresh(struct device *dev,
3386 struct device_attribute *attr,
3390 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3393 ret = rbd_dev_refresh(rbd_dev);
3395 return ret < 0 ? ret : size;
3398 static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
3399 static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL);
3400 static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
3401 static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
3402 static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
3403 static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL);
3404 static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
3405 static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL);
3406 static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
3407 static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
3408 static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL);
3410 static struct attribute *rbd_attrs[] = {
3411 &dev_attr_size.attr,
3412 &dev_attr_features.attr,
3413 &dev_attr_major.attr,
3414 &dev_attr_client_id.attr,
3415 &dev_attr_pool.attr,
3416 &dev_attr_pool_id.attr,
3417 &dev_attr_name.attr,
3418 &dev_attr_image_id.attr,
3419 &dev_attr_current_snap.attr,
3420 &dev_attr_parent.attr,
3421 &dev_attr_refresh.attr,
3425 static struct attribute_group rbd_attr_group = {
3429 static const struct attribute_group *rbd_attr_groups[] = {
3434 static void rbd_sysfs_dev_release(struct device *dev)
3438 static struct device_type rbd_device_type = {
3440 .groups = rbd_attr_groups,
3441 .release = rbd_sysfs_dev_release,
3444 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
3446 kref_get(&spec->kref);
3451 static void rbd_spec_free(struct kref *kref);
3452 static void rbd_spec_put(struct rbd_spec *spec)
3455 kref_put(&spec->kref, rbd_spec_free);
3458 static struct rbd_spec *rbd_spec_alloc(void)
3460 struct rbd_spec *spec;
3462 spec = kzalloc(sizeof (*spec), GFP_KERNEL);
3465 kref_init(&spec->kref);
3470 static void rbd_spec_free(struct kref *kref)
3472 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
3474 kfree(spec->pool_name);
3475 kfree(spec->image_id);
3476 kfree(spec->image_name);
3477 kfree(spec->snap_name);
3481 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
3482 struct rbd_spec *spec)
3484 struct rbd_device *rbd_dev;
3486 rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL);
3490 spin_lock_init(&rbd_dev->lock);
3492 INIT_LIST_HEAD(&rbd_dev->node);
3493 init_rwsem(&rbd_dev->header_rwsem);
3495 rbd_dev->spec = spec;
3496 rbd_dev->rbd_client = rbdc;
3498 /* Initialize the layout used for all rbd requests */
3500 rbd_dev->layout.fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3501 rbd_dev->layout.fl_stripe_count = cpu_to_le32(1);
3502 rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3503 rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id);
3508 static void rbd_dev_destroy(struct rbd_device *rbd_dev)
3510 rbd_put_client(rbd_dev->rbd_client);
3511 rbd_spec_put(rbd_dev->spec);
3516 * Get the size and object order for an image snapshot, or if
3517 * snap_id is CEPH_NOSNAP, gets this information for the base
3520 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
3521 u8 *order, u64 *snap_size)
3523 __le64 snapid = cpu_to_le64(snap_id);
3528 } __attribute__ ((packed)) size_buf = { 0 };
3530 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3532 &snapid, sizeof (snapid),
3533 &size_buf, sizeof (size_buf));
3534 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3537 if (ret < sizeof (size_buf))
3541 *order = size_buf.order;
3542 *snap_size = le64_to_cpu(size_buf.size);
3544 dout(" snap_id 0x%016llx order = %u, snap_size = %llu\n",
3545 (unsigned long long)snap_id, (unsigned int)*order,
3546 (unsigned long long)*snap_size);
3551 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
3553 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
3554 &rbd_dev->header.obj_order,
3555 &rbd_dev->header.image_size);
3558 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
3564 reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL);
3568 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3569 "rbd", "get_object_prefix", NULL, 0,
3570 reply_buf, RBD_OBJ_PREFIX_LEN_MAX);
3571 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3576 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
3577 p + ret, NULL, GFP_NOIO);
3580 if (IS_ERR(rbd_dev->header.object_prefix)) {
3581 ret = PTR_ERR(rbd_dev->header.object_prefix);
3582 rbd_dev->header.object_prefix = NULL;
3584 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix);
3592 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
3595 __le64 snapid = cpu_to_le64(snap_id);
3599 } __attribute__ ((packed)) features_buf = { 0 };
3603 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3604 "rbd", "get_features",
3605 &snapid, sizeof (snapid),
3606 &features_buf, sizeof (features_buf));
3607 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3610 if (ret < sizeof (features_buf))
3613 incompat = le64_to_cpu(features_buf.incompat);
3614 if (incompat & ~RBD_FEATURES_SUPPORTED)
3617 *snap_features = le64_to_cpu(features_buf.features);
3619 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
3620 (unsigned long long)snap_id,
3621 (unsigned long long)*snap_features,
3622 (unsigned long long)le64_to_cpu(features_buf.incompat));
3627 static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
3629 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
3630 &rbd_dev->header.features);
3633 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
3635 struct rbd_spec *parent_spec;
3637 void *reply_buf = NULL;
3645 parent_spec = rbd_spec_alloc();
3649 size = sizeof (__le64) + /* pool_id */
3650 sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */
3651 sizeof (__le64) + /* snap_id */
3652 sizeof (__le64); /* overlap */
3653 reply_buf = kmalloc(size, GFP_KERNEL);
3659 snapid = cpu_to_le64(CEPH_NOSNAP);
3660 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3661 "rbd", "get_parent",
3662 &snapid, sizeof (snapid),
3664 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3669 end = reply_buf + ret;
3671 ceph_decode_64_safe(&p, end, parent_spec->pool_id, out_err);
3672 if (parent_spec->pool_id == CEPH_NOPOOL)
3673 goto out; /* No parent? No problem. */
3675 /* The ceph file layout needs to fit pool id in 32 bits */
3678 if (parent_spec->pool_id > (u64)U32_MAX) {
3679 rbd_warn(NULL, "parent pool id too large (%llu > %u)\n",
3680 (unsigned long long)parent_spec->pool_id, U32_MAX);
3684 image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
3685 if (IS_ERR(image_id)) {
3686 ret = PTR_ERR(image_id);
3689 parent_spec->image_id = image_id;
3690 ceph_decode_64_safe(&p, end, parent_spec->snap_id, out_err);
3691 ceph_decode_64_safe(&p, end, overlap, out_err);
3693 rbd_dev->parent_overlap = overlap;
3694 rbd_dev->parent_spec = parent_spec;
3695 parent_spec = NULL; /* rbd_dev now owns this */
3700 rbd_spec_put(parent_spec);
3705 static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
3709 __le64 stripe_count;
3710 } __attribute__ ((packed)) striping_info_buf = { 0 };
3711 size_t size = sizeof (striping_info_buf);
3718 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3719 "rbd", "get_stripe_unit_count", NULL, 0,
3720 (char *)&striping_info_buf, size);
3721 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3728 * We don't actually support the "fancy striping" feature
3729 * (STRIPINGV2) yet, but if the striping sizes are the
3730 * defaults the behavior is the same as before. So find
3731 * out, and only fail if the image has non-default values.
3734 obj_size = (u64)1 << rbd_dev->header.obj_order;
3735 p = &striping_info_buf;
3736 stripe_unit = ceph_decode_64(&p);
3737 if (stripe_unit != obj_size) {
3738 rbd_warn(rbd_dev, "unsupported stripe unit "
3739 "(got %llu want %llu)",
3740 stripe_unit, obj_size);
3743 stripe_count = ceph_decode_64(&p);
3744 if (stripe_count != 1) {
3745 rbd_warn(rbd_dev, "unsupported stripe count "
3746 "(got %llu want 1)", stripe_count);
3749 rbd_dev->header.stripe_unit = stripe_unit;
3750 rbd_dev->header.stripe_count = stripe_count;
3755 static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
3757 size_t image_id_size;
3762 void *reply_buf = NULL;
3764 char *image_name = NULL;
3767 rbd_assert(!rbd_dev->spec->image_name);
3769 len = strlen(rbd_dev->spec->image_id);
3770 image_id_size = sizeof (__le32) + len;
3771 image_id = kmalloc(image_id_size, GFP_KERNEL);
3776 end = image_id + image_id_size;
3777 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
3779 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
3780 reply_buf = kmalloc(size, GFP_KERNEL);
3784 ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY,
3785 "rbd", "dir_get_name",
3786 image_id, image_id_size,
3791 end = reply_buf + ret;
3793 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
3794 if (IS_ERR(image_name))
3797 dout("%s: name is %s len is %zd\n", __func__, image_name, len);
3805 static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
3807 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
3808 const char *snap_name;
3811 /* Skip over names until we find the one we are looking for */
3813 snap_name = rbd_dev->header.snap_names;
3814 while (which < snapc->num_snaps) {
3815 if (!strcmp(name, snap_name))
3816 return snapc->snaps[which];
3817 snap_name += strlen(snap_name) + 1;
3823 static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
3825 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
3830 for (which = 0; !found && which < snapc->num_snaps; which++) {
3831 const char *snap_name;
3833 snap_id = snapc->snaps[which];
3834 snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
3835 if (IS_ERR(snap_name))
3837 found = !strcmp(name, snap_name);
3840 return found ? snap_id : CEPH_NOSNAP;
3844 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
3845 * no snapshot by that name is found, or if an error occurs.
3847 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
3849 if (rbd_dev->image_format == 1)
3850 return rbd_v1_snap_id_by_name(rbd_dev, name);
3852 return rbd_v2_snap_id_by_name(rbd_dev, name);
3856 * When an rbd image has a parent image, it is identified by the
3857 * pool, image, and snapshot ids (not names). This function fills
3858 * in the names for those ids. (It's OK if we can't figure out the
3859 * name for an image id, but the pool and snapshot ids should always
3860 * exist and have names.) All names in an rbd spec are dynamically
3863 * When an image being mapped (not a parent) is probed, we have the
3864 * pool name and pool id, image name and image id, and the snapshot
3865 * name. The only thing we're missing is the snapshot id.
3867 static int rbd_dev_spec_update(struct rbd_device *rbd_dev)
3869 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3870 struct rbd_spec *spec = rbd_dev->spec;
3871 const char *pool_name;
3872 const char *image_name;
3873 const char *snap_name;
3877 * An image being mapped will have the pool name (etc.), but
3878 * we need to look up the snapshot id.
3880 if (spec->pool_name) {
3881 if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
3884 snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
3885 if (snap_id == CEPH_NOSNAP)
3887 spec->snap_id = snap_id;
3889 spec->snap_id = CEPH_NOSNAP;
3895 /* Get the pool name; we have to make our own copy of this */
3897 pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
3899 rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
3902 pool_name = kstrdup(pool_name, GFP_KERNEL);
3906 /* Fetch the image name; tolerate failure here */
3908 image_name = rbd_dev_image_name(rbd_dev);
3910 rbd_warn(rbd_dev, "unable to get image name");
3912 /* Look up the snapshot name, and make a copy */
3914 snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
3920 spec->pool_name = pool_name;
3921 spec->image_name = image_name;
3922 spec->snap_name = snap_name;
3932 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
3941 struct ceph_snap_context *snapc;
3945 * We'll need room for the seq value (maximum snapshot id),
3946 * snapshot count, and array of that many snapshot ids.
3947 * For now we have a fixed upper limit on the number we're
3948 * prepared to receive.
3950 size = sizeof (__le64) + sizeof (__le32) +
3951 RBD_MAX_SNAP_COUNT * sizeof (__le64);
3952 reply_buf = kzalloc(size, GFP_KERNEL);
3956 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3957 "rbd", "get_snapcontext", NULL, 0,
3959 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3964 end = reply_buf + ret;
3966 ceph_decode_64_safe(&p, end, seq, out);
3967 ceph_decode_32_safe(&p, end, snap_count, out);
3970 * Make sure the reported number of snapshot ids wouldn't go
3971 * beyond the end of our buffer. But before checking that,
3972 * make sure the computed size of the snapshot context we
3973 * allocate is representable in a size_t.
3975 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
3980 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
3984 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
3990 for (i = 0; i < snap_count; i++)
3991 snapc->snaps[i] = ceph_decode_64(&p);
3993 rbd_dev->header.snapc = snapc;
3995 dout(" snap context seq = %llu, snap_count = %u\n",
3996 (unsigned long long)seq, (unsigned int)snap_count);
4003 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
4014 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
4015 reply_buf = kmalloc(size, GFP_KERNEL);
4017 return ERR_PTR(-ENOMEM);
4019 snapid = cpu_to_le64(snap_id);
4020 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4021 "rbd", "get_snapshot_name",
4022 &snapid, sizeof (snapid),
4024 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4026 snap_name = ERR_PTR(ret);
4031 end = reply_buf + ret;
4032 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
4033 if (IS_ERR(snap_name))
4036 dout(" snap_id 0x%016llx snap_name = %s\n",
4037 (unsigned long long)snap_id, snap_name);
4044 static int rbd_dev_v2_refresh(struct rbd_device *rbd_dev)
4048 down_write(&rbd_dev->header_rwsem);
4050 ret = rbd_dev_v2_image_size(rbd_dev);
4053 rbd_update_mapping_size(rbd_dev);
4055 ret = rbd_dev_v2_snap_context(rbd_dev);
4056 dout("rbd_dev_v2_snap_context returned %d\n", ret);
4060 up_write(&rbd_dev->header_rwsem);
4065 static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
4070 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
4072 dev = &rbd_dev->dev;
4073 dev->bus = &rbd_bus_type;
4074 dev->type = &rbd_device_type;
4075 dev->parent = &rbd_root_dev;
4076 dev->release = rbd_dev_device_release;
4077 dev_set_name(dev, "%d", rbd_dev->dev_id);
4078 ret = device_register(dev);
4080 mutex_unlock(&ctl_mutex);
4085 static void rbd_bus_del_dev(struct rbd_device *rbd_dev)
4087 device_unregister(&rbd_dev->dev);
4090 static atomic64_t rbd_dev_id_max = ATOMIC64_INIT(0);
4093 * Get a unique rbd identifier for the given new rbd_dev, and add
4094 * the rbd_dev to the global list. The minimum rbd id is 1.
4096 static void rbd_dev_id_get(struct rbd_device *rbd_dev)
4098 rbd_dev->dev_id = atomic64_inc_return(&rbd_dev_id_max);
4100 spin_lock(&rbd_dev_list_lock);
4101 list_add_tail(&rbd_dev->node, &rbd_dev_list);
4102 spin_unlock(&rbd_dev_list_lock);
4103 dout("rbd_dev %p given dev id %llu\n", rbd_dev,
4104 (unsigned long long) rbd_dev->dev_id);
4108 * Remove an rbd_dev from the global list, and record that its
4109 * identifier is no longer in use.
4111 static void rbd_dev_id_put(struct rbd_device *rbd_dev)
4113 struct list_head *tmp;
4114 int rbd_id = rbd_dev->dev_id;
4117 rbd_assert(rbd_id > 0);
4119 dout("rbd_dev %p released dev id %llu\n", rbd_dev,
4120 (unsigned long long) rbd_dev->dev_id);
4121 spin_lock(&rbd_dev_list_lock);
4122 list_del_init(&rbd_dev->node);
4125 * If the id being "put" is not the current maximum, there
4126 * is nothing special we need to do.
4128 if (rbd_id != atomic64_read(&rbd_dev_id_max)) {
4129 spin_unlock(&rbd_dev_list_lock);
4134 * We need to update the current maximum id. Search the
4135 * list to find out what it is. We're more likely to find
4136 * the maximum at the end, so search the list backward.
4139 list_for_each_prev(tmp, &rbd_dev_list) {
4140 struct rbd_device *rbd_dev;
4142 rbd_dev = list_entry(tmp, struct rbd_device, node);
4143 if (rbd_dev->dev_id > max_id)
4144 max_id = rbd_dev->dev_id;
4146 spin_unlock(&rbd_dev_list_lock);
4149 * The max id could have been updated by rbd_dev_id_get(), in
4150 * which case it now accurately reflects the new maximum.
4151 * Be careful not to overwrite the maximum value in that
4154 atomic64_cmpxchg(&rbd_dev_id_max, rbd_id, max_id);
4155 dout(" max dev id has been reset\n");
4159 * Skips over white space at *buf, and updates *buf to point to the
4160 * first found non-space character (if any). Returns the length of
4161 * the token (string of non-white space characters) found. Note
4162 * that *buf must be terminated with '\0'.
4164 static inline size_t next_token(const char **buf)
4167 * These are the characters that produce nonzero for
4168 * isspace() in the "C" and "POSIX" locales.
4170 const char *spaces = " \f\n\r\t\v";
4172 *buf += strspn(*buf, spaces); /* Find start of token */
4174 return strcspn(*buf, spaces); /* Return token length */
4178 * Finds the next token in *buf, and if the provided token buffer is
4179 * big enough, copies the found token into it. The result, if
4180 * copied, is guaranteed to be terminated with '\0'. Note that *buf
4181 * must be terminated with '\0' on entry.
4183 * Returns the length of the token found (not including the '\0').
4184 * Return value will be 0 if no token is found, and it will be >=
4185 * token_size if the token would not fit.
4187 * The *buf pointer will be updated to point beyond the end of the
4188 * found token. Note that this occurs even if the token buffer is
4189 * too small to hold it.
4191 static inline size_t copy_token(const char **buf,
4197 len = next_token(buf);
4198 if (len < token_size) {
4199 memcpy(token, *buf, len);
4200 *(token + len) = '\0';
4208 * Finds the next token in *buf, dynamically allocates a buffer big
4209 * enough to hold a copy of it, and copies the token into the new
4210 * buffer. The copy is guaranteed to be terminated with '\0'. Note
4211 * that a duplicate buffer is created even for a zero-length token.
4213 * Returns a pointer to the newly-allocated duplicate, or a null
4214 * pointer if memory for the duplicate was not available. If
4215 * the lenp argument is a non-null pointer, the length of the token
4216 * (not including the '\0') is returned in *lenp.
4218 * If successful, the *buf pointer will be updated to point beyond
4219 * the end of the found token.
4221 * Note: uses GFP_KERNEL for allocation.
4223 static inline char *dup_token(const char **buf, size_t *lenp)
4228 len = next_token(buf);
4229 dup = kmemdup(*buf, len + 1, GFP_KERNEL);
4232 *(dup + len) = '\0';
4242 * Parse the options provided for an "rbd add" (i.e., rbd image
4243 * mapping) request. These arrive via a write to /sys/bus/rbd/add,
4244 * and the data written is passed here via a NUL-terminated buffer.
4245 * Returns 0 if successful or an error code otherwise.
4247 * The information extracted from these options is recorded in
4248 * the other parameters which return dynamically-allocated
4251 * The address of a pointer that will refer to a ceph options
4252 * structure. Caller must release the returned pointer using
4253 * ceph_destroy_options() when it is no longer needed.
4255 * Address of an rbd options pointer. Fully initialized by
4256 * this function; caller must release with kfree().
4258 * Address of an rbd image specification pointer. Fully
4259 * initialized by this function based on parsed options.
4260 * Caller must release with rbd_spec_put().
4262 * The options passed take this form:
4263 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
4266 * A comma-separated list of one or more monitor addresses.
4267 * A monitor address is an ip address, optionally followed
4268 * by a port number (separated by a colon).
4269 * I.e.: ip1[:port1][,ip2[:port2]...]
4271 * A comma-separated list of ceph and/or rbd options.
4273 * The name of the rados pool containing the rbd image.
4275 * The name of the image in that pool to map.
4277 * An optional snapshot id. If provided, the mapping will
4278 * present data from the image at the time that snapshot was
4279 * created. The image head is used if no snapshot id is
4280 * provided. Snapshot mappings are always read-only.
4282 static int rbd_add_parse_args(const char *buf,
4283 struct ceph_options **ceph_opts,
4284 struct rbd_options **opts,
4285 struct rbd_spec **rbd_spec)
4289 const char *mon_addrs;
4291 size_t mon_addrs_size;
4292 struct rbd_spec *spec = NULL;
4293 struct rbd_options *rbd_opts = NULL;
4294 struct ceph_options *copts;
4297 /* The first four tokens are required */
4299 len = next_token(&buf);
4301 rbd_warn(NULL, "no monitor address(es) provided");
4305 mon_addrs_size = len + 1;
4309 options = dup_token(&buf, NULL);
4313 rbd_warn(NULL, "no options provided");
4317 spec = rbd_spec_alloc();
4321 spec->pool_name = dup_token(&buf, NULL);
4322 if (!spec->pool_name)
4324 if (!*spec->pool_name) {
4325 rbd_warn(NULL, "no pool name provided");
4329 spec->image_name = dup_token(&buf, NULL);
4330 if (!spec->image_name)
4332 if (!*spec->image_name) {
4333 rbd_warn(NULL, "no image name provided");
4338 * Snapshot name is optional; default is to use "-"
4339 * (indicating the head/no snapshot).
4341 len = next_token(&buf);
4343 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
4344 len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
4345 } else if (len > RBD_MAX_SNAP_NAME_LEN) {
4346 ret = -ENAMETOOLONG;
4349 snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
4352 *(snap_name + len) = '\0';
4353 spec->snap_name = snap_name;
4355 /* Initialize all rbd options to the defaults */
4357 rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL);
4361 rbd_opts->read_only = RBD_READ_ONLY_DEFAULT;
4363 copts = ceph_parse_options(options, mon_addrs,
4364 mon_addrs + mon_addrs_size - 1,
4365 parse_rbd_opts_token, rbd_opts);
4366 if (IS_ERR(copts)) {
4367 ret = PTR_ERR(copts);
4388 * An rbd format 2 image has a unique identifier, distinct from the
4389 * name given to it by the user. Internally, that identifier is
4390 * what's used to specify the names of objects related to the image.
4392 * A special "rbd id" object is used to map an rbd image name to its
4393 * id. If that object doesn't exist, then there is no v2 rbd image
4394 * with the supplied name.
4396 * This function will record the given rbd_dev's image_id field if
4397 * it can be determined, and in that case will return 0. If any
4398 * errors occur a negative errno will be returned and the rbd_dev's
4399 * image_id field will be unchanged (and should be NULL).
4401 static int rbd_dev_image_id(struct rbd_device *rbd_dev)
4410 * When probing a parent image, the image id is already
4411 * known (and the image name likely is not). There's no
4412 * need to fetch the image id again in this case. We
4413 * do still need to set the image format though.
4415 if (rbd_dev->spec->image_id) {
4416 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;
4422 * First, see if the format 2 image id file exists, and if
4423 * so, get the image's persistent id from it.
4425 size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name);
4426 object_name = kmalloc(size, GFP_NOIO);
4429 sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name);
4430 dout("rbd id object name is %s\n", object_name);
4432 /* Response will be an encoded string, which includes a length */
4434 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
4435 response = kzalloc(size, GFP_NOIO);
4441 /* If it doesn't exist we'll assume it's a format 1 image */
4443 ret = rbd_obj_method_sync(rbd_dev, object_name,
4444 "rbd", "get_id", NULL, 0,
4445 response, RBD_IMAGE_ID_LEN_MAX);
4446 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4447 if (ret == -ENOENT) {
4448 image_id = kstrdup("", GFP_KERNEL);
4449 ret = image_id ? 0 : -ENOMEM;
4451 rbd_dev->image_format = 1;
4452 } else if (ret > sizeof (__le32)) {
4455 image_id = ceph_extract_encoded_string(&p, p + ret,
4457 ret = IS_ERR(image_id) ? PTR_ERR(image_id) : 0;
4459 rbd_dev->image_format = 2;
4465 rbd_dev->spec->image_id = image_id;
4466 dout("image_id is %s\n", image_id);
4475 /* Undo whatever state changes are made by v1 or v2 image probe */
4477 static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
4479 struct rbd_image_header *header;
4481 rbd_dev_remove_parent(rbd_dev);
4482 rbd_spec_put(rbd_dev->parent_spec);
4483 rbd_dev->parent_spec = NULL;
4484 rbd_dev->parent_overlap = 0;
4486 /* Free dynamic fields from the header, then zero it out */
4488 header = &rbd_dev->header;
4489 ceph_put_snap_context(header->snapc);
4490 kfree(header->snap_sizes);
4491 kfree(header->snap_names);
4492 kfree(header->object_prefix);
4493 memset(header, 0, sizeof (*header));
4496 static int rbd_dev_v1_probe(struct rbd_device *rbd_dev)
4500 /* Populate rbd image metadata */
4502 ret = rbd_read_header(rbd_dev, &rbd_dev->header);
4506 /* Version 1 images have no parent (no layering) */
4508 rbd_dev->parent_spec = NULL;
4509 rbd_dev->parent_overlap = 0;
4511 dout("discovered version 1 image, header name is %s\n",
4512 rbd_dev->header_name);
4517 kfree(rbd_dev->header_name);
4518 rbd_dev->header_name = NULL;
4519 kfree(rbd_dev->spec->image_id);
4520 rbd_dev->spec->image_id = NULL;
4525 static int rbd_dev_v2_probe(struct rbd_device *rbd_dev)
4529 ret = rbd_dev_v2_image_size(rbd_dev);
4533 /* Get the object prefix (a.k.a. block_name) for the image */
4535 ret = rbd_dev_v2_object_prefix(rbd_dev);
4539 /* Get the and check features for the image */
4541 ret = rbd_dev_v2_features(rbd_dev);
4545 /* If the image supports layering, get the parent info */
4547 if (rbd_dev->header.features & RBD_FEATURE_LAYERING) {
4548 ret = rbd_dev_v2_parent_info(rbd_dev);
4553 * Don't print a warning for parent images. We can
4554 * tell this point because we won't know its pool
4555 * name yet (just its pool id).
4557 if (rbd_dev->spec->pool_name)
4558 rbd_warn(rbd_dev, "WARNING: kernel layering "
4559 "is EXPERIMENTAL!");
4562 /* If the image supports fancy striping, get its parameters */
4564 if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
4565 ret = rbd_dev_v2_striping_info(rbd_dev);
4570 /* crypto and compression type aren't (yet) supported for v2 images */
4572 rbd_dev->header.crypt_type = 0;
4573 rbd_dev->header.comp_type = 0;
4575 /* Get the snapshot context, plus the header version */
4577 ret = rbd_dev_v2_snap_context(rbd_dev);
4581 dout("discovered version 2 image, header name is %s\n",
4582 rbd_dev->header_name);
4586 rbd_dev->parent_overlap = 0;
4587 rbd_spec_put(rbd_dev->parent_spec);
4588 rbd_dev->parent_spec = NULL;
4589 kfree(rbd_dev->header_name);
4590 rbd_dev->header_name = NULL;
4591 kfree(rbd_dev->header.object_prefix);
4592 rbd_dev->header.object_prefix = NULL;
4597 static int rbd_dev_probe_parent(struct rbd_device *rbd_dev)
4599 struct rbd_device *parent = NULL;
4600 struct rbd_spec *parent_spec;
4601 struct rbd_client *rbdc;
4604 if (!rbd_dev->parent_spec)
4607 * We need to pass a reference to the client and the parent
4608 * spec when creating the parent rbd_dev. Images related by
4609 * parent/child relationships always share both.
4611 parent_spec = rbd_spec_get(rbd_dev->parent_spec);
4612 rbdc = __rbd_get_client(rbd_dev->rbd_client);
4615 parent = rbd_dev_create(rbdc, parent_spec);
4619 ret = rbd_dev_image_probe(parent);
4622 rbd_dev->parent = parent;
4627 rbd_spec_put(rbd_dev->parent_spec);
4628 kfree(rbd_dev->header_name);
4629 rbd_dev_destroy(parent);
4631 rbd_put_client(rbdc);
4632 rbd_spec_put(parent_spec);
4638 static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
4642 ret = rbd_dev_mapping_set(rbd_dev);
4646 /* generate unique id: find highest unique id, add one */
4647 rbd_dev_id_get(rbd_dev);
4649 /* Fill in the device name, now that we have its id. */
4650 BUILD_BUG_ON(DEV_NAME_LEN
4651 < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
4652 sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id);
4654 /* Get our block major device number. */
4656 ret = register_blkdev(0, rbd_dev->name);
4659 rbd_dev->major = ret;
4661 /* Set up the blkdev mapping. */
4663 ret = rbd_init_disk(rbd_dev);
4665 goto err_out_blkdev;
4667 ret = rbd_bus_add_dev(rbd_dev);
4671 /* Everything's ready. Announce the disk to the world. */
4673 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
4674 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
4675 add_disk(rbd_dev->disk);
4677 pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name,
4678 (unsigned long long) rbd_dev->mapping.size);
4683 rbd_free_disk(rbd_dev);
4685 unregister_blkdev(rbd_dev->major, rbd_dev->name);
4687 rbd_dev_id_put(rbd_dev);
4688 rbd_dev_mapping_clear(rbd_dev);
4693 static int rbd_dev_header_name(struct rbd_device *rbd_dev)
4695 struct rbd_spec *spec = rbd_dev->spec;
4698 /* Record the header object name for this rbd image. */
4700 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
4702 if (rbd_dev->image_format == 1)
4703 size = strlen(spec->image_name) + sizeof (RBD_SUFFIX);
4705 size = sizeof (RBD_HEADER_PREFIX) + strlen(spec->image_id);
4707 rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
4708 if (!rbd_dev->header_name)
4711 if (rbd_dev->image_format == 1)
4712 sprintf(rbd_dev->header_name, "%s%s",
4713 spec->image_name, RBD_SUFFIX);
4715 sprintf(rbd_dev->header_name, "%s%s",
4716 RBD_HEADER_PREFIX, spec->image_id);
4720 static void rbd_dev_image_release(struct rbd_device *rbd_dev)
4724 rbd_dev_unprobe(rbd_dev);
4725 ret = rbd_dev_header_watch_sync(rbd_dev, 0);
4727 rbd_warn(rbd_dev, "failed to cancel watch event (%d)\n", ret);
4728 kfree(rbd_dev->header_name);
4729 rbd_dev->header_name = NULL;
4730 rbd_dev->image_format = 0;
4731 kfree(rbd_dev->spec->image_id);
4732 rbd_dev->spec->image_id = NULL;
4734 rbd_dev_destroy(rbd_dev);
4738 * Probe for the existence of the header object for the given rbd
4739 * device. For format 2 images this includes determining the image
4742 static int rbd_dev_image_probe(struct rbd_device *rbd_dev)
4748 * Get the id from the image id object. If it's not a
4749 * format 2 image, we'll get ENOENT back, and we'll assume
4750 * it's a format 1 image.
4752 ret = rbd_dev_image_id(rbd_dev);
4755 rbd_assert(rbd_dev->spec->image_id);
4756 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
4758 ret = rbd_dev_header_name(rbd_dev);
4760 goto err_out_format;
4762 ret = rbd_dev_header_watch_sync(rbd_dev, 1);
4764 goto out_header_name;
4766 if (rbd_dev->image_format == 1)
4767 ret = rbd_dev_v1_probe(rbd_dev);
4769 ret = rbd_dev_v2_probe(rbd_dev);
4773 ret = rbd_dev_spec_update(rbd_dev);
4777 ret = rbd_dev_probe_parent(rbd_dev);
4782 rbd_dev_unprobe(rbd_dev);
4784 tmp = rbd_dev_header_watch_sync(rbd_dev, 0);
4786 rbd_warn(rbd_dev, "unable to tear down watch request\n");
4788 kfree(rbd_dev->header_name);
4789 rbd_dev->header_name = NULL;
4791 rbd_dev->image_format = 0;
4792 kfree(rbd_dev->spec->image_id);
4793 rbd_dev->spec->image_id = NULL;
4795 dout("probe failed, returning %d\n", ret);
4800 static ssize_t rbd_add(struct bus_type *bus,
4804 struct rbd_device *rbd_dev = NULL;
4805 struct ceph_options *ceph_opts = NULL;
4806 struct rbd_options *rbd_opts = NULL;
4807 struct rbd_spec *spec = NULL;
4808 struct rbd_client *rbdc;
4809 struct ceph_osd_client *osdc;
4812 if (!try_module_get(THIS_MODULE))
4815 /* parse add command */
4816 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
4818 goto err_out_module;
4820 rbdc = rbd_get_client(ceph_opts);
4825 ceph_opts = NULL; /* rbd_dev client now owns this */
4828 osdc = &rbdc->client->osdc;
4829 rc = ceph_pg_poolid_by_name(osdc->osdmap, spec->pool_name);
4831 goto err_out_client;
4832 spec->pool_id = (u64)rc;
4834 /* The ceph file layout needs to fit pool id in 32 bits */
4836 if (spec->pool_id > (u64)U32_MAX) {
4837 rbd_warn(NULL, "pool id too large (%llu > %u)\n",
4838 (unsigned long long)spec->pool_id, U32_MAX);
4840 goto err_out_client;
4843 rbd_dev = rbd_dev_create(rbdc, spec);
4845 goto err_out_client;
4846 rbdc = NULL; /* rbd_dev now owns this */
4847 spec = NULL; /* rbd_dev now owns this */
4849 rbd_dev->mapping.read_only = rbd_opts->read_only;
4851 rbd_opts = NULL; /* done with this */
4853 rc = rbd_dev_image_probe(rbd_dev);
4855 goto err_out_rbd_dev;
4857 rc = rbd_dev_device_setup(rbd_dev);
4861 rbd_dev_image_release(rbd_dev);
4863 rbd_dev_destroy(rbd_dev);
4865 rbd_put_client(rbdc);
4868 ceph_destroy_options(ceph_opts);
4872 module_put(THIS_MODULE);
4874 dout("Error adding device %s\n", buf);
4879 static struct rbd_device *__rbd_get_dev(unsigned long dev_id)
4881 struct list_head *tmp;
4882 struct rbd_device *rbd_dev;
4884 spin_lock(&rbd_dev_list_lock);
4885 list_for_each(tmp, &rbd_dev_list) {
4886 rbd_dev = list_entry(tmp, struct rbd_device, node);
4887 if (rbd_dev->dev_id == dev_id) {
4888 spin_unlock(&rbd_dev_list_lock);
4892 spin_unlock(&rbd_dev_list_lock);
4896 static void rbd_dev_device_release(struct device *dev)
4898 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4900 rbd_free_disk(rbd_dev);
4901 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
4902 rbd_dev_clear_mapping(rbd_dev);
4903 unregister_blkdev(rbd_dev->major, rbd_dev->name);
4905 rbd_dev_id_put(rbd_dev);
4906 rbd_dev_mapping_clear(rbd_dev);
4909 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
4911 while (rbd_dev->parent) {
4912 struct rbd_device *first = rbd_dev;
4913 struct rbd_device *second = first->parent;
4914 struct rbd_device *third;
4917 * Follow to the parent with no grandparent and
4920 while (second && (third = second->parent)) {
4925 rbd_dev_image_release(second);
4926 first->parent = NULL;
4927 first->parent_overlap = 0;
4929 rbd_assert(first->parent_spec);
4930 rbd_spec_put(first->parent_spec);
4931 first->parent_spec = NULL;
4935 static ssize_t rbd_remove(struct bus_type *bus,
4939 struct rbd_device *rbd_dev = NULL;
4944 ret = strict_strtoul(buf, 10, &ul);
4948 /* convert to int; abort if we lost anything in the conversion */
4949 target_id = (int) ul;
4950 if (target_id != ul)
4953 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
4955 rbd_dev = __rbd_get_dev(target_id);
4961 spin_lock_irq(&rbd_dev->lock);
4962 if (rbd_dev->open_count)
4965 set_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags);
4966 spin_unlock_irq(&rbd_dev->lock);
4970 rbd_bus_del_dev(rbd_dev);
4971 rbd_dev_image_release(rbd_dev);
4972 module_put(THIS_MODULE);
4974 mutex_unlock(&ctl_mutex);
4980 * create control files in sysfs
4983 static int rbd_sysfs_init(void)
4987 ret = device_register(&rbd_root_dev);
4991 ret = bus_register(&rbd_bus_type);
4993 device_unregister(&rbd_root_dev);
4998 static void rbd_sysfs_cleanup(void)
5000 bus_unregister(&rbd_bus_type);
5001 device_unregister(&rbd_root_dev);
5004 static int rbd_slab_init(void)
5006 rbd_assert(!rbd_img_request_cache);
5007 rbd_img_request_cache = kmem_cache_create("rbd_img_request",
5008 sizeof (struct rbd_img_request),
5009 __alignof__(struct rbd_img_request),
5011 if (rbd_img_request_cache)
5017 static void rbd_slab_exit(void)
5019 rbd_assert(rbd_img_request_cache);
5020 kmem_cache_destroy(rbd_img_request_cache);
5021 rbd_img_request_cache = NULL;
5024 static int __init rbd_init(void)
5028 if (!libceph_compatible(NULL)) {
5029 rbd_warn(NULL, "libceph incompatibility (quitting)");
5033 rc = rbd_slab_init();
5036 rc = rbd_sysfs_init();
5040 pr_info("loaded " RBD_DRV_NAME_LONG "\n");
5045 static void __exit rbd_exit(void)
5047 rbd_sysfs_cleanup();
5051 module_init(rbd_init);
5052 module_exit(rbd_exit);
5054 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
5055 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
5056 MODULE_DESCRIPTION("rados block device");
5058 /* following authorship retained from original osdblk.c */
5059 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
5061 MODULE_LICENSE("GPL");