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>
44 #include <linux/idr.h>
46 #include "rbd_types.h"
48 #define RBD_DEBUG /* Activate rbd_assert() calls */
51 * The basic unit of block I/O is a sector. It is interpreted in a
52 * number of contexts in Linux (blk, bio, genhd), but the default is
53 * universally 512 bytes. These symbols are just slightly more
54 * meaningful than the bare numbers they represent.
56 #define SECTOR_SHIFT 9
57 #define SECTOR_SIZE (1ULL << SECTOR_SHIFT)
60 * Increment the given counter and return its updated value.
61 * If the counter is already 0 it will not be incremented.
62 * If the counter is already at its maximum value returns
63 * -EINVAL without updating it.
65 static int atomic_inc_return_safe(atomic_t *v)
69 counter = (unsigned int)__atomic_add_unless(v, 1, 0);
70 if (counter <= (unsigned int)INT_MAX)
78 /* Decrement the counter. Return the resulting value, or -EINVAL */
79 static int atomic_dec_return_safe(atomic_t *v)
83 counter = atomic_dec_return(v);
92 #define RBD_DRV_NAME "rbd"
94 #define RBD_MINORS_PER_MAJOR 256
95 #define RBD_SINGLE_MAJOR_PART_SHIFT 4
97 #define RBD_SNAP_DEV_NAME_PREFIX "snap_"
98 #define RBD_MAX_SNAP_NAME_LEN \
99 (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1))
101 #define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */
103 #define RBD_SNAP_HEAD_NAME "-"
105 #define BAD_SNAP_INDEX U32_MAX /* invalid index into snap array */
107 /* This allows a single page to hold an image name sent by OSD */
108 #define RBD_IMAGE_NAME_LEN_MAX (PAGE_SIZE - sizeof (__le32) - 1)
109 #define RBD_IMAGE_ID_LEN_MAX 64
111 #define RBD_OBJ_PREFIX_LEN_MAX 64
115 #define RBD_FEATURE_LAYERING (1<<0)
116 #define RBD_FEATURE_STRIPINGV2 (1<<1)
117 #define RBD_FEATURES_ALL \
118 (RBD_FEATURE_LAYERING | RBD_FEATURE_STRIPINGV2)
120 /* Features supported by this (client software) implementation. */
122 #define RBD_FEATURES_SUPPORTED (RBD_FEATURES_ALL)
125 * An RBD device name will be "rbd#", where the "rbd" comes from
126 * RBD_DRV_NAME above, and # is a unique integer identifier.
127 * MAX_INT_FORMAT_WIDTH is used in ensuring DEV_NAME_LEN is big
128 * enough to hold all possible device names.
130 #define DEV_NAME_LEN 32
131 #define MAX_INT_FORMAT_WIDTH ((5 * sizeof (int)) / 2 + 1)
134 * block device image metadata (in-memory version)
136 struct rbd_image_header {
137 /* These six fields never change for a given rbd image */
144 u64 features; /* Might be changeable someday? */
146 /* The remaining fields need to be updated occasionally */
148 struct ceph_snap_context *snapc;
149 char *snap_names; /* format 1 only */
150 u64 *snap_sizes; /* format 1 only */
154 * An rbd image specification.
156 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely
157 * identify an image. Each rbd_dev structure includes a pointer to
158 * an rbd_spec structure that encapsulates this identity.
160 * Each of the id's in an rbd_spec has an associated name. For a
161 * user-mapped image, the names are supplied and the id's associated
162 * with them are looked up. For a layered image, a parent image is
163 * defined by the tuple, and the names are looked up.
165 * An rbd_dev structure contains a parent_spec pointer which is
166 * non-null if the image it represents is a child in a layered
167 * image. This pointer will refer to the rbd_spec structure used
168 * by the parent rbd_dev for its own identity (i.e., the structure
169 * is shared between the parent and child).
171 * Since these structures are populated once, during the discovery
172 * phase of image construction, they are effectively immutable so
173 * we make no effort to synchronize access to them.
175 * Note that code herein does not assume the image name is known (it
176 * could be a null pointer).
180 const char *pool_name;
182 const char *image_id;
183 const char *image_name;
186 const char *snap_name;
192 * an instance of the client. multiple devices may share an rbd client.
195 struct ceph_client *client;
197 struct list_head node;
200 struct rbd_img_request;
201 typedef void (*rbd_img_callback_t)(struct rbd_img_request *);
203 #define BAD_WHICH U32_MAX /* Good which or bad which, which? */
205 struct rbd_obj_request;
206 typedef void (*rbd_obj_callback_t)(struct rbd_obj_request *);
208 enum obj_request_type {
209 OBJ_REQUEST_NODATA, OBJ_REQUEST_BIO, OBJ_REQUEST_PAGES
213 OBJ_REQ_DONE, /* completion flag: not done = 0, done = 1 */
214 OBJ_REQ_IMG_DATA, /* object usage: standalone = 0, image = 1 */
215 OBJ_REQ_KNOWN, /* EXISTS flag valid: no = 0, yes = 1 */
216 OBJ_REQ_EXISTS, /* target exists: no = 0, yes = 1 */
219 struct rbd_obj_request {
220 const char *object_name;
221 u64 offset; /* object start byte */
222 u64 length; /* bytes from offset */
226 * An object request associated with an image will have its
227 * img_data flag set; a standalone object request will not.
229 * A standalone object request will have which == BAD_WHICH
230 * and a null obj_request pointer.
232 * An object request initiated in support of a layered image
233 * object (to check for its existence before a write) will
234 * have which == BAD_WHICH and a non-null obj_request pointer.
236 * Finally, an object request for rbd image data will have
237 * which != BAD_WHICH, and will have a non-null img_request
238 * pointer. The value of which will be in the range
239 * 0..(img_request->obj_request_count-1).
242 struct rbd_obj_request *obj_request; /* STAT op */
244 struct rbd_img_request *img_request;
246 /* links for img_request->obj_requests list */
247 struct list_head links;
250 u32 which; /* posn image request list */
252 enum obj_request_type type;
254 struct bio *bio_list;
260 struct page **copyup_pages;
261 u32 copyup_page_count;
263 struct ceph_osd_request *osd_req;
265 u64 xferred; /* bytes transferred */
268 rbd_obj_callback_t callback;
269 struct completion completion;
275 IMG_REQ_WRITE, /* I/O direction: read = 0, write = 1 */
276 IMG_REQ_CHILD, /* initiator: block = 0, child image = 1 */
277 IMG_REQ_LAYERED, /* ENOENT handling: normal = 0, layered = 1 */
280 struct rbd_img_request {
281 struct rbd_device *rbd_dev;
282 u64 offset; /* starting image byte offset */
283 u64 length; /* byte count from offset */
286 u64 snap_id; /* for reads */
287 struct ceph_snap_context *snapc; /* for writes */
290 struct request *rq; /* block request */
291 struct rbd_obj_request *obj_request; /* obj req initiator */
293 struct page **copyup_pages;
294 u32 copyup_page_count;
295 spinlock_t completion_lock;/* protects next_completion */
297 rbd_img_callback_t callback;
298 u64 xferred;/* aggregate bytes transferred */
299 int result; /* first nonzero obj_request result */
301 u32 obj_request_count;
302 struct list_head obj_requests; /* rbd_obj_request structs */
307 #define for_each_obj_request(ireq, oreq) \
308 list_for_each_entry(oreq, &(ireq)->obj_requests, links)
309 #define for_each_obj_request_from(ireq, oreq) \
310 list_for_each_entry_from(oreq, &(ireq)->obj_requests, links)
311 #define for_each_obj_request_safe(ireq, oreq, n) \
312 list_for_each_entry_safe_reverse(oreq, n, &(ireq)->obj_requests, links)
324 int dev_id; /* blkdev unique id */
326 int major; /* blkdev assigned major */
328 struct gendisk *disk; /* blkdev's gendisk and rq */
330 u32 image_format; /* Either 1 or 2 */
331 struct rbd_client *rbd_client;
333 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */
335 spinlock_t lock; /* queue, flags, open_count */
337 struct rbd_image_header header;
338 unsigned long flags; /* possibly lock protected */
339 struct rbd_spec *spec;
343 struct ceph_file_layout layout;
345 struct ceph_osd_event *watch_event;
346 struct rbd_obj_request *watch_request;
348 struct rbd_spec *parent_spec;
351 struct rbd_device *parent;
353 /* protects updating the header */
354 struct rw_semaphore header_rwsem;
356 struct rbd_mapping mapping;
358 struct list_head node;
362 unsigned long open_count; /* protected by lock */
366 * Flag bits for rbd_dev->flags. If atomicity is required,
367 * rbd_dev->lock is used to protect access.
369 * Currently, only the "removing" flag (which is coupled with the
370 * "open_count" field) requires atomic access.
373 RBD_DEV_FLAG_EXISTS, /* mapped snapshot has not been deleted */
374 RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */
377 static DEFINE_MUTEX(client_mutex); /* Serialize client creation */
379 static LIST_HEAD(rbd_dev_list); /* devices */
380 static DEFINE_SPINLOCK(rbd_dev_list_lock);
382 static LIST_HEAD(rbd_client_list); /* clients */
383 static DEFINE_SPINLOCK(rbd_client_list_lock);
385 /* Slab caches for frequently-allocated structures */
387 static struct kmem_cache *rbd_img_request_cache;
388 static struct kmem_cache *rbd_obj_request_cache;
389 static struct kmem_cache *rbd_segment_name_cache;
391 static int rbd_major;
392 static DEFINE_IDA(rbd_dev_id_ida);
395 * Default to false for now, as single-major requires >= 0.75 version of
396 * userspace rbd utility.
398 static bool single_major = false;
399 module_param(single_major, bool, S_IRUGO);
400 MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: false)");
402 static int rbd_img_request_submit(struct rbd_img_request *img_request);
404 static void rbd_dev_device_release(struct device *dev);
406 static ssize_t rbd_add(struct bus_type *bus, const char *buf,
408 static ssize_t rbd_remove(struct bus_type *bus, const char *buf,
410 static ssize_t rbd_add_single_major(struct bus_type *bus, const char *buf,
412 static ssize_t rbd_remove_single_major(struct bus_type *bus, const char *buf,
414 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping);
415 static void rbd_spec_put(struct rbd_spec *spec);
417 static int rbd_dev_id_to_minor(int dev_id)
419 return dev_id << RBD_SINGLE_MAJOR_PART_SHIFT;
422 static int minor_to_rbd_dev_id(int minor)
424 return minor >> RBD_SINGLE_MAJOR_PART_SHIFT;
427 static BUS_ATTR(add, S_IWUSR, NULL, rbd_add);
428 static BUS_ATTR(remove, S_IWUSR, NULL, rbd_remove);
429 static BUS_ATTR(add_single_major, S_IWUSR, NULL, rbd_add_single_major);
430 static BUS_ATTR(remove_single_major, S_IWUSR, NULL, rbd_remove_single_major);
432 static struct attribute *rbd_bus_attrs[] = {
434 &bus_attr_remove.attr,
435 &bus_attr_add_single_major.attr,
436 &bus_attr_remove_single_major.attr,
440 static umode_t rbd_bus_is_visible(struct kobject *kobj,
441 struct attribute *attr, int index)
444 (attr == &bus_attr_add_single_major.attr ||
445 attr == &bus_attr_remove_single_major.attr))
451 static const struct attribute_group rbd_bus_group = {
452 .attrs = rbd_bus_attrs,
453 .is_visible = rbd_bus_is_visible,
455 __ATTRIBUTE_GROUPS(rbd_bus);
457 static struct bus_type rbd_bus_type = {
459 .bus_groups = rbd_bus_groups,
462 static void rbd_root_dev_release(struct device *dev)
466 static struct device rbd_root_dev = {
468 .release = rbd_root_dev_release,
471 static __printf(2, 3)
472 void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...)
474 struct va_format vaf;
482 printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf);
483 else if (rbd_dev->disk)
484 printk(KERN_WARNING "%s: %s: %pV\n",
485 RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf);
486 else if (rbd_dev->spec && rbd_dev->spec->image_name)
487 printk(KERN_WARNING "%s: image %s: %pV\n",
488 RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf);
489 else if (rbd_dev->spec && rbd_dev->spec->image_id)
490 printk(KERN_WARNING "%s: id %s: %pV\n",
491 RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf);
493 printk(KERN_WARNING "%s: rbd_dev %p: %pV\n",
494 RBD_DRV_NAME, rbd_dev, &vaf);
499 #define rbd_assert(expr) \
500 if (unlikely(!(expr))) { \
501 printk(KERN_ERR "\nAssertion failure in %s() " \
503 "\trbd_assert(%s);\n\n", \
504 __func__, __LINE__, #expr); \
507 #else /* !RBD_DEBUG */
508 # define rbd_assert(expr) ((void) 0)
509 #endif /* !RBD_DEBUG */
511 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request);
512 static void rbd_img_parent_read(struct rbd_obj_request *obj_request);
513 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev);
515 static int rbd_dev_refresh(struct rbd_device *rbd_dev);
516 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev);
517 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev);
518 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
520 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
521 u8 *order, u64 *snap_size);
522 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
524 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name);
526 static int rbd_open(struct block_device *bdev, fmode_t mode)
528 struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
529 bool removing = false;
531 if ((mode & FMODE_WRITE) && rbd_dev->mapping.read_only)
534 spin_lock_irq(&rbd_dev->lock);
535 if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags))
538 rbd_dev->open_count++;
539 spin_unlock_irq(&rbd_dev->lock);
543 (void) get_device(&rbd_dev->dev);
548 static void rbd_release(struct gendisk *disk, fmode_t mode)
550 struct rbd_device *rbd_dev = disk->private_data;
551 unsigned long open_count_before;
553 spin_lock_irq(&rbd_dev->lock);
554 open_count_before = rbd_dev->open_count--;
555 spin_unlock_irq(&rbd_dev->lock);
556 rbd_assert(open_count_before > 0);
558 put_device(&rbd_dev->dev);
561 static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg)
566 bool ro_changed = false;
568 /* get_user() may sleep, so call it before taking rbd_dev->lock */
569 if (get_user(val, (int __user *)(arg)))
572 ro = val ? true : false;
573 /* Snapshot doesn't allow to write*/
574 if (rbd_dev->spec->snap_id != CEPH_NOSNAP && !ro)
577 spin_lock_irq(&rbd_dev->lock);
578 /* prevent others open this device */
579 if (rbd_dev->open_count > 1) {
584 if (rbd_dev->mapping.read_only != ro) {
585 rbd_dev->mapping.read_only = ro;
590 spin_unlock_irq(&rbd_dev->lock);
591 /* set_disk_ro() may sleep, so call it after releasing rbd_dev->lock */
592 if (ret == 0 && ro_changed)
593 set_disk_ro(rbd_dev->disk, ro ? 1 : 0);
598 static int rbd_ioctl(struct block_device *bdev, fmode_t mode,
599 unsigned int cmd, unsigned long arg)
601 struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
606 ret = rbd_ioctl_set_ro(rbd_dev, arg);
616 static int rbd_compat_ioctl(struct block_device *bdev, fmode_t mode,
617 unsigned int cmd, unsigned long arg)
619 return rbd_ioctl(bdev, mode, cmd, arg);
621 #endif /* CONFIG_COMPAT */
623 static const struct block_device_operations rbd_bd_ops = {
624 .owner = THIS_MODULE,
626 .release = rbd_release,
629 .compat_ioctl = rbd_compat_ioctl,
634 * Initialize an rbd client instance. Success or not, this function
635 * consumes ceph_opts. Caller holds client_mutex.
637 static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
639 struct rbd_client *rbdc;
642 dout("%s:\n", __func__);
643 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
647 kref_init(&rbdc->kref);
648 INIT_LIST_HEAD(&rbdc->node);
650 rbdc->client = ceph_create_client(ceph_opts, rbdc, 0, 0);
651 if (IS_ERR(rbdc->client))
653 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
655 ret = ceph_open_session(rbdc->client);
659 spin_lock(&rbd_client_list_lock);
660 list_add_tail(&rbdc->node, &rbd_client_list);
661 spin_unlock(&rbd_client_list_lock);
663 dout("%s: rbdc %p\n", __func__, rbdc);
667 ceph_destroy_client(rbdc->client);
672 ceph_destroy_options(ceph_opts);
673 dout("%s: error %d\n", __func__, ret);
678 static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
680 kref_get(&rbdc->kref);
686 * Find a ceph client with specific addr and configuration. If
687 * found, bump its reference count.
689 static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
691 struct rbd_client *client_node;
694 if (ceph_opts->flags & CEPH_OPT_NOSHARE)
697 spin_lock(&rbd_client_list_lock);
698 list_for_each_entry(client_node, &rbd_client_list, node) {
699 if (!ceph_compare_options(ceph_opts, client_node->client)) {
700 __rbd_get_client(client_node);
706 spin_unlock(&rbd_client_list_lock);
708 return found ? client_node : NULL;
718 /* string args above */
721 /* Boolean args above */
725 static match_table_t rbd_opts_tokens = {
727 /* string args above */
728 {Opt_read_only, "read_only"},
729 {Opt_read_only, "ro"}, /* Alternate spelling */
730 {Opt_read_write, "read_write"},
731 {Opt_read_write, "rw"}, /* Alternate spelling */
732 /* Boolean args above */
740 #define RBD_READ_ONLY_DEFAULT false
742 static int parse_rbd_opts_token(char *c, void *private)
744 struct rbd_options *rbd_opts = private;
745 substring_t argstr[MAX_OPT_ARGS];
746 int token, intval, ret;
748 token = match_token(c, rbd_opts_tokens, argstr);
752 if (token < Opt_last_int) {
753 ret = match_int(&argstr[0], &intval);
755 pr_err("bad mount option arg (not int) "
759 dout("got int token %d val %d\n", token, intval);
760 } else if (token > Opt_last_int && token < Opt_last_string) {
761 dout("got string token %d val %s\n", token,
763 } else if (token > Opt_last_string && token < Opt_last_bool) {
764 dout("got Boolean token %d\n", token);
766 dout("got token %d\n", token);
771 rbd_opts->read_only = true;
774 rbd_opts->read_only = false;
784 * Get a ceph client with specific addr and configuration, if one does
785 * not exist create it. Either way, ceph_opts is consumed by this
788 static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
790 struct rbd_client *rbdc;
792 mutex_lock_nested(&client_mutex, SINGLE_DEPTH_NESTING);
793 rbdc = rbd_client_find(ceph_opts);
794 if (rbdc) /* using an existing client */
795 ceph_destroy_options(ceph_opts);
797 rbdc = rbd_client_create(ceph_opts);
798 mutex_unlock(&client_mutex);
804 * Destroy ceph client
806 * Caller must hold rbd_client_list_lock.
808 static void rbd_client_release(struct kref *kref)
810 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
812 dout("%s: rbdc %p\n", __func__, rbdc);
813 spin_lock(&rbd_client_list_lock);
814 list_del(&rbdc->node);
815 spin_unlock(&rbd_client_list_lock);
817 ceph_destroy_client(rbdc->client);
822 * Drop reference to ceph client node. If it's not referenced anymore, release
825 static void rbd_put_client(struct rbd_client *rbdc)
828 kref_put(&rbdc->kref, rbd_client_release);
831 static bool rbd_image_format_valid(u32 image_format)
833 return image_format == 1 || image_format == 2;
836 static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
841 /* The header has to start with the magic rbd header text */
842 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
845 /* The bio layer requires at least sector-sized I/O */
847 if (ondisk->options.order < SECTOR_SHIFT)
850 /* If we use u64 in a few spots we may be able to loosen this */
852 if (ondisk->options.order > 8 * sizeof (int) - 1)
856 * The size of a snapshot header has to fit in a size_t, and
857 * that limits the number of snapshots.
859 snap_count = le32_to_cpu(ondisk->snap_count);
860 size = SIZE_MAX - sizeof (struct ceph_snap_context);
861 if (snap_count > size / sizeof (__le64))
865 * Not only that, but the size of the entire the snapshot
866 * header must also be representable in a size_t.
868 size -= snap_count * sizeof (__le64);
869 if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
876 * Fill an rbd image header with information from the given format 1
879 static int rbd_header_from_disk(struct rbd_device *rbd_dev,
880 struct rbd_image_header_ondisk *ondisk)
882 struct rbd_image_header *header = &rbd_dev->header;
883 bool first_time = header->object_prefix == NULL;
884 struct ceph_snap_context *snapc;
885 char *object_prefix = NULL;
886 char *snap_names = NULL;
887 u64 *snap_sizes = NULL;
893 /* Allocate this now to avoid having to handle failure below */
898 len = strnlen(ondisk->object_prefix,
899 sizeof (ondisk->object_prefix));
900 object_prefix = kmalloc(len + 1, GFP_KERNEL);
903 memcpy(object_prefix, ondisk->object_prefix, len);
904 object_prefix[len] = '\0';
907 /* Allocate the snapshot context and fill it in */
909 snap_count = le32_to_cpu(ondisk->snap_count);
910 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
913 snapc->seq = le64_to_cpu(ondisk->snap_seq);
915 struct rbd_image_snap_ondisk *snaps;
916 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);
918 /* We'll keep a copy of the snapshot names... */
920 if (snap_names_len > (u64)SIZE_MAX)
922 snap_names = kmalloc(snap_names_len, GFP_KERNEL);
926 /* ...as well as the array of their sizes. */
928 size = snap_count * sizeof (*header->snap_sizes);
929 snap_sizes = kmalloc(size, GFP_KERNEL);
934 * Copy the names, and fill in each snapshot's id
937 * Note that rbd_dev_v1_header_info() guarantees the
938 * ondisk buffer we're working with has
939 * snap_names_len bytes beyond the end of the
940 * snapshot id array, this memcpy() is safe.
942 memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len);
943 snaps = ondisk->snaps;
944 for (i = 0; i < snap_count; i++) {
945 snapc->snaps[i] = le64_to_cpu(snaps[i].id);
946 snap_sizes[i] = le64_to_cpu(snaps[i].image_size);
950 /* We won't fail any more, fill in the header */
953 header->object_prefix = object_prefix;
954 header->obj_order = ondisk->options.order;
955 header->crypt_type = ondisk->options.crypt_type;
956 header->comp_type = ondisk->options.comp_type;
957 /* The rest aren't used for format 1 images */
958 header->stripe_unit = 0;
959 header->stripe_count = 0;
960 header->features = 0;
962 ceph_put_snap_context(header->snapc);
963 kfree(header->snap_names);
964 kfree(header->snap_sizes);
967 /* The remaining fields always get updated (when we refresh) */
969 header->image_size = le64_to_cpu(ondisk->image_size);
970 header->snapc = snapc;
971 header->snap_names = snap_names;
972 header->snap_sizes = snap_sizes;
974 /* Make sure mapping size is consistent with header info */
976 if (rbd_dev->spec->snap_id == CEPH_NOSNAP || first_time)
977 if (rbd_dev->mapping.size != header->image_size)
978 rbd_dev->mapping.size = header->image_size;
986 ceph_put_snap_context(snapc);
987 kfree(object_prefix);
992 static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
994 const char *snap_name;
996 rbd_assert(which < rbd_dev->header.snapc->num_snaps);
998 /* Skip over names until we find the one we are looking for */
1000 snap_name = rbd_dev->header.snap_names;
1002 snap_name += strlen(snap_name) + 1;
1004 return kstrdup(snap_name, GFP_KERNEL);
1008 * Snapshot id comparison function for use with qsort()/bsearch().
1009 * Note that result is for snapshots in *descending* order.
1011 static int snapid_compare_reverse(const void *s1, const void *s2)
1013 u64 snap_id1 = *(u64 *)s1;
1014 u64 snap_id2 = *(u64 *)s2;
1016 if (snap_id1 < snap_id2)
1018 return snap_id1 == snap_id2 ? 0 : -1;
1022 * Search a snapshot context to see if the given snapshot id is
1025 * Returns the position of the snapshot id in the array if it's found,
1026 * or BAD_SNAP_INDEX otherwise.
1028 * Note: The snapshot array is in kept sorted (by the osd) in
1029 * reverse order, highest snapshot id first.
1031 static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id)
1033 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
1036 found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps,
1037 sizeof (snap_id), snapid_compare_reverse);
1039 return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX;
1042 static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
1046 const char *snap_name;
1048 which = rbd_dev_snap_index(rbd_dev, snap_id);
1049 if (which == BAD_SNAP_INDEX)
1050 return ERR_PTR(-ENOENT);
1052 snap_name = _rbd_dev_v1_snap_name(rbd_dev, which);
1053 return snap_name ? snap_name : ERR_PTR(-ENOMEM);
1056 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
1058 if (snap_id == CEPH_NOSNAP)
1059 return RBD_SNAP_HEAD_NAME;
1061 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1062 if (rbd_dev->image_format == 1)
1063 return rbd_dev_v1_snap_name(rbd_dev, snap_id);
1065 return rbd_dev_v2_snap_name(rbd_dev, snap_id);
1068 static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
1071 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1072 if (snap_id == CEPH_NOSNAP) {
1073 *snap_size = rbd_dev->header.image_size;
1074 } else if (rbd_dev->image_format == 1) {
1077 which = rbd_dev_snap_index(rbd_dev, snap_id);
1078 if (which == BAD_SNAP_INDEX)
1081 *snap_size = rbd_dev->header.snap_sizes[which];
1086 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
1095 static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
1098 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1099 if (snap_id == CEPH_NOSNAP) {
1100 *snap_features = rbd_dev->header.features;
1101 } else if (rbd_dev->image_format == 1) {
1102 *snap_features = 0; /* No features for format 1 */
1107 ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features);
1111 *snap_features = features;
1116 static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
1118 u64 snap_id = rbd_dev->spec->snap_id;
1123 ret = rbd_snap_size(rbd_dev, snap_id, &size);
1126 ret = rbd_snap_features(rbd_dev, snap_id, &features);
1130 rbd_dev->mapping.size = size;
1131 rbd_dev->mapping.features = features;
1136 static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
1138 rbd_dev->mapping.size = 0;
1139 rbd_dev->mapping.features = 0;
1142 static void rbd_segment_name_free(const char *name)
1144 /* The explicit cast here is needed to drop the const qualifier */
1146 kmem_cache_free(rbd_segment_name_cache, (void *)name);
1149 static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset)
1156 name = kmem_cache_alloc(rbd_segment_name_cache, GFP_NOIO);
1159 segment = offset >> rbd_dev->header.obj_order;
1160 name_format = "%s.%012llx";
1161 if (rbd_dev->image_format == 2)
1162 name_format = "%s.%016llx";
1163 ret = snprintf(name, CEPH_MAX_OID_NAME_LEN + 1, name_format,
1164 rbd_dev->header.object_prefix, segment);
1165 if (ret < 0 || ret > CEPH_MAX_OID_NAME_LEN) {
1166 pr_err("error formatting segment name for #%llu (%d)\n",
1168 rbd_segment_name_free(name);
1175 static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset)
1177 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1179 return offset & (segment_size - 1);
1182 static u64 rbd_segment_length(struct rbd_device *rbd_dev,
1183 u64 offset, u64 length)
1185 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1187 offset &= segment_size - 1;
1189 rbd_assert(length <= U64_MAX - offset);
1190 if (offset + length > segment_size)
1191 length = segment_size - offset;
1197 * returns the size of an object in the image
1199 static u64 rbd_obj_bytes(struct rbd_image_header *header)
1201 return 1 << header->obj_order;
1208 static void bio_chain_put(struct bio *chain)
1214 chain = chain->bi_next;
1220 * zeros a bio chain, starting at specific offset
1222 static void zero_bio_chain(struct bio *chain, int start_ofs)
1225 struct bvec_iter iter;
1226 unsigned long flags;
1231 bio_for_each_segment(bv, chain, iter) {
1232 if (pos + bv.bv_len > start_ofs) {
1233 int remainder = max(start_ofs - pos, 0);
1234 buf = bvec_kmap_irq(&bv, &flags);
1235 memset(buf + remainder, 0,
1236 bv.bv_len - remainder);
1237 flush_dcache_page(bv.bv_page);
1238 bvec_kunmap_irq(buf, &flags);
1243 chain = chain->bi_next;
1248 * similar to zero_bio_chain(), zeros data defined by a page array,
1249 * starting at the given byte offset from the start of the array and
1250 * continuing up to the given end offset. The pages array is
1251 * assumed to be big enough to hold all bytes up to the end.
1253 static void zero_pages(struct page **pages, u64 offset, u64 end)
1255 struct page **page = &pages[offset >> PAGE_SHIFT];
1257 rbd_assert(end > offset);
1258 rbd_assert(end - offset <= (u64)SIZE_MAX);
1259 while (offset < end) {
1262 unsigned long flags;
1265 page_offset = offset & ~PAGE_MASK;
1266 length = min_t(size_t, PAGE_SIZE - page_offset, end - offset);
1267 local_irq_save(flags);
1268 kaddr = kmap_atomic(*page);
1269 memset(kaddr + page_offset, 0, length);
1270 flush_dcache_page(*page);
1271 kunmap_atomic(kaddr);
1272 local_irq_restore(flags);
1280 * Clone a portion of a bio, starting at the given byte offset
1281 * and continuing for the number of bytes indicated.
1283 static struct bio *bio_clone_range(struct bio *bio_src,
1284 unsigned int offset,
1290 bio = bio_clone(bio_src, gfpmask);
1292 return NULL; /* ENOMEM */
1294 bio_advance(bio, offset);
1295 bio->bi_iter.bi_size = len;
1301 * Clone a portion of a bio chain, starting at the given byte offset
1302 * into the first bio in the source chain and continuing for the
1303 * number of bytes indicated. The result is another bio chain of
1304 * exactly the given length, or a null pointer on error.
1306 * The bio_src and offset parameters are both in-out. On entry they
1307 * refer to the first source bio and the offset into that bio where
1308 * the start of data to be cloned is located.
1310 * On return, bio_src is updated to refer to the bio in the source
1311 * chain that contains first un-cloned byte, and *offset will
1312 * contain the offset of that byte within that bio.
1314 static struct bio *bio_chain_clone_range(struct bio **bio_src,
1315 unsigned int *offset,
1319 struct bio *bi = *bio_src;
1320 unsigned int off = *offset;
1321 struct bio *chain = NULL;
1324 /* Build up a chain of clone bios up to the limit */
1326 if (!bi || off >= bi->bi_iter.bi_size || !len)
1327 return NULL; /* Nothing to clone */
1331 unsigned int bi_size;
1335 rbd_warn(NULL, "bio_chain exhausted with %u left", len);
1336 goto out_err; /* EINVAL; ran out of bio's */
1338 bi_size = min_t(unsigned int, bi->bi_iter.bi_size - off, len);
1339 bio = bio_clone_range(bi, off, bi_size, gfpmask);
1341 goto out_err; /* ENOMEM */
1344 end = &bio->bi_next;
1347 if (off == bi->bi_iter.bi_size) {
1358 bio_chain_put(chain);
1364 * The default/initial value for all object request flags is 0. For
1365 * each flag, once its value is set to 1 it is never reset to 0
1368 static void obj_request_img_data_set(struct rbd_obj_request *obj_request)
1370 if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) {
1371 struct rbd_device *rbd_dev;
1373 rbd_dev = obj_request->img_request->rbd_dev;
1374 rbd_warn(rbd_dev, "obj_request %p already marked img_data\n",
1379 static bool obj_request_img_data_test(struct rbd_obj_request *obj_request)
1382 return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0;
1385 static void obj_request_done_set(struct rbd_obj_request *obj_request)
1387 if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) {
1388 struct rbd_device *rbd_dev = NULL;
1390 if (obj_request_img_data_test(obj_request))
1391 rbd_dev = obj_request->img_request->rbd_dev;
1392 rbd_warn(rbd_dev, "obj_request %p already marked done\n",
1397 static bool obj_request_done_test(struct rbd_obj_request *obj_request)
1400 return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0;
1404 * This sets the KNOWN flag after (possibly) setting the EXISTS
1405 * flag. The latter is set based on the "exists" value provided.
1407 * Note that for our purposes once an object exists it never goes
1408 * away again. It's possible that the response from two existence
1409 * checks are separated by the creation of the target object, and
1410 * the first ("doesn't exist") response arrives *after* the second
1411 * ("does exist"). In that case we ignore the second one.
1413 static void obj_request_existence_set(struct rbd_obj_request *obj_request,
1417 set_bit(OBJ_REQ_EXISTS, &obj_request->flags);
1418 set_bit(OBJ_REQ_KNOWN, &obj_request->flags);
1422 static bool obj_request_known_test(struct rbd_obj_request *obj_request)
1425 return test_bit(OBJ_REQ_KNOWN, &obj_request->flags) != 0;
1428 static bool obj_request_exists_test(struct rbd_obj_request *obj_request)
1431 return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0;
1434 static bool obj_request_overlaps_parent(struct rbd_obj_request *obj_request)
1436 struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev;
1438 return obj_request->img_offset <
1439 round_up(rbd_dev->parent_overlap, rbd_obj_bytes(&rbd_dev->header));
1442 static void rbd_obj_request_get(struct rbd_obj_request *obj_request)
1444 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1445 atomic_read(&obj_request->kref.refcount));
1446 kref_get(&obj_request->kref);
1449 static void rbd_obj_request_destroy(struct kref *kref);
1450 static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
1452 rbd_assert(obj_request != NULL);
1453 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1454 atomic_read(&obj_request->kref.refcount));
1455 kref_put(&obj_request->kref, rbd_obj_request_destroy);
1458 static void rbd_img_request_get(struct rbd_img_request *img_request)
1460 dout("%s: img %p (was %d)\n", __func__, img_request,
1461 atomic_read(&img_request->kref.refcount));
1462 kref_get(&img_request->kref);
1465 static bool img_request_child_test(struct rbd_img_request *img_request);
1466 static void rbd_parent_request_destroy(struct kref *kref);
1467 static void rbd_img_request_destroy(struct kref *kref);
1468 static void rbd_img_request_put(struct rbd_img_request *img_request)
1470 rbd_assert(img_request != NULL);
1471 dout("%s: img %p (was %d)\n", __func__, img_request,
1472 atomic_read(&img_request->kref.refcount));
1473 if (img_request_child_test(img_request))
1474 kref_put(&img_request->kref, rbd_parent_request_destroy);
1476 kref_put(&img_request->kref, rbd_img_request_destroy);
1479 static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
1480 struct rbd_obj_request *obj_request)
1482 rbd_assert(obj_request->img_request == NULL);
1484 /* Image request now owns object's original reference */
1485 obj_request->img_request = img_request;
1486 obj_request->which = img_request->obj_request_count;
1487 rbd_assert(!obj_request_img_data_test(obj_request));
1488 obj_request_img_data_set(obj_request);
1489 rbd_assert(obj_request->which != BAD_WHICH);
1490 img_request->obj_request_count++;
1491 list_add_tail(&obj_request->links, &img_request->obj_requests);
1492 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1493 obj_request->which);
1496 static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
1497 struct rbd_obj_request *obj_request)
1499 rbd_assert(obj_request->which != BAD_WHICH);
1501 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1502 obj_request->which);
1503 list_del(&obj_request->links);
1504 rbd_assert(img_request->obj_request_count > 0);
1505 img_request->obj_request_count--;
1506 rbd_assert(obj_request->which == img_request->obj_request_count);
1507 obj_request->which = BAD_WHICH;
1508 rbd_assert(obj_request_img_data_test(obj_request));
1509 rbd_assert(obj_request->img_request == img_request);
1510 obj_request->img_request = NULL;
1511 obj_request->callback = NULL;
1512 rbd_obj_request_put(obj_request);
1515 static bool obj_request_type_valid(enum obj_request_type type)
1518 case OBJ_REQUEST_NODATA:
1519 case OBJ_REQUEST_BIO:
1520 case OBJ_REQUEST_PAGES:
1527 static int rbd_obj_request_submit(struct ceph_osd_client *osdc,
1528 struct rbd_obj_request *obj_request)
1530 dout("%s %p\n", __func__, obj_request);
1531 return ceph_osdc_start_request(osdc, obj_request->osd_req, false);
1534 static void rbd_obj_request_end(struct rbd_obj_request *obj_request)
1536 dout("%s %p\n", __func__, obj_request);
1537 ceph_osdc_cancel_request(obj_request->osd_req);
1541 * Wait for an object request to complete. If interrupted, cancel the
1542 * underlying osd request.
1544 static int rbd_obj_request_wait(struct rbd_obj_request *obj_request)
1548 dout("%s %p\n", __func__, obj_request);
1550 ret = wait_for_completion_interruptible(&obj_request->completion);
1552 dout("%s %p interrupted\n", __func__, obj_request);
1553 rbd_obj_request_end(obj_request);
1557 dout("%s %p done\n", __func__, obj_request);
1561 static void rbd_img_request_complete(struct rbd_img_request *img_request)
1564 dout("%s: img %p\n", __func__, img_request);
1567 * If no error occurred, compute the aggregate transfer
1568 * count for the image request. We could instead use
1569 * atomic64_cmpxchg() to update it as each object request
1570 * completes; not clear which way is better off hand.
1572 if (!img_request->result) {
1573 struct rbd_obj_request *obj_request;
1576 for_each_obj_request(img_request, obj_request)
1577 xferred += obj_request->xferred;
1578 img_request->xferred = xferred;
1581 if (img_request->callback)
1582 img_request->callback(img_request);
1584 rbd_img_request_put(img_request);
1588 * The default/initial value for all image request flags is 0. Each
1589 * is conditionally set to 1 at image request initialization time
1590 * and currently never change thereafter.
1592 static void img_request_write_set(struct rbd_img_request *img_request)
1594 set_bit(IMG_REQ_WRITE, &img_request->flags);
1598 static bool img_request_write_test(struct rbd_img_request *img_request)
1601 return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0;
1604 static void img_request_child_set(struct rbd_img_request *img_request)
1606 set_bit(IMG_REQ_CHILD, &img_request->flags);
1610 static void img_request_child_clear(struct rbd_img_request *img_request)
1612 clear_bit(IMG_REQ_CHILD, &img_request->flags);
1616 static bool img_request_child_test(struct rbd_img_request *img_request)
1619 return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0;
1622 static void img_request_layered_set(struct rbd_img_request *img_request)
1624 set_bit(IMG_REQ_LAYERED, &img_request->flags);
1628 static void img_request_layered_clear(struct rbd_img_request *img_request)
1630 clear_bit(IMG_REQ_LAYERED, &img_request->flags);
1634 static bool img_request_layered_test(struct rbd_img_request *img_request)
1637 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
1641 rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
1643 u64 xferred = obj_request->xferred;
1644 u64 length = obj_request->length;
1646 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1647 obj_request, obj_request->img_request, obj_request->result,
1650 * ENOENT means a hole in the image. We zero-fill the entire
1651 * length of the request. A short read also implies zero-fill
1652 * to the end of the request. An error requires the whole
1653 * length of the request to be reported finished with an error
1654 * to the block layer. In each case we update the xferred
1655 * count to indicate the whole request was satisfied.
1657 rbd_assert(obj_request->type != OBJ_REQUEST_NODATA);
1658 if (obj_request->result == -ENOENT) {
1659 if (obj_request->type == OBJ_REQUEST_BIO)
1660 zero_bio_chain(obj_request->bio_list, 0);
1662 zero_pages(obj_request->pages, 0, length);
1663 obj_request->result = 0;
1664 } else if (xferred < length && !obj_request->result) {
1665 if (obj_request->type == OBJ_REQUEST_BIO)
1666 zero_bio_chain(obj_request->bio_list, xferred);
1668 zero_pages(obj_request->pages, xferred, length);
1670 obj_request->xferred = length;
1671 obj_request_done_set(obj_request);
1674 static void rbd_obj_request_complete(struct rbd_obj_request *obj_request)
1676 dout("%s: obj %p cb %p\n", __func__, obj_request,
1677 obj_request->callback);
1678 if (obj_request->callback)
1679 obj_request->callback(obj_request);
1681 complete_all(&obj_request->completion);
1684 static void rbd_osd_trivial_callback(struct rbd_obj_request *obj_request)
1686 dout("%s: obj %p\n", __func__, obj_request);
1687 obj_request_done_set(obj_request);
1690 static void rbd_osd_read_callback(struct rbd_obj_request *obj_request)
1692 struct rbd_img_request *img_request = NULL;
1693 struct rbd_device *rbd_dev = NULL;
1694 bool layered = false;
1696 if (obj_request_img_data_test(obj_request)) {
1697 img_request = obj_request->img_request;
1698 layered = img_request && img_request_layered_test(img_request);
1699 rbd_dev = img_request->rbd_dev;
1702 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1703 obj_request, img_request, obj_request->result,
1704 obj_request->xferred, obj_request->length);
1705 if (layered && obj_request->result == -ENOENT &&
1706 obj_request->img_offset < rbd_dev->parent_overlap)
1707 rbd_img_parent_read(obj_request);
1708 else if (img_request)
1709 rbd_img_obj_request_read_callback(obj_request);
1711 obj_request_done_set(obj_request);
1714 static void rbd_osd_write_callback(struct rbd_obj_request *obj_request)
1716 dout("%s: obj %p result %d %llu\n", __func__, obj_request,
1717 obj_request->result, obj_request->length);
1719 * There is no such thing as a successful short write. Set
1720 * it to our originally-requested length.
1722 obj_request->xferred = obj_request->length;
1723 obj_request_done_set(obj_request);
1727 * For a simple stat call there's nothing to do. We'll do more if
1728 * this is part of a write sequence for a layered image.
1730 static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request)
1732 dout("%s: obj %p\n", __func__, obj_request);
1733 obj_request_done_set(obj_request);
1736 static void rbd_osd_req_callback(struct ceph_osd_request *osd_req,
1737 struct ceph_msg *msg)
1739 struct rbd_obj_request *obj_request = osd_req->r_priv;
1742 dout("%s: osd_req %p msg %p\n", __func__, osd_req, msg);
1743 rbd_assert(osd_req == obj_request->osd_req);
1744 if (obj_request_img_data_test(obj_request)) {
1745 rbd_assert(obj_request->img_request);
1746 rbd_assert(obj_request->which != BAD_WHICH);
1748 rbd_assert(obj_request->which == BAD_WHICH);
1751 if (osd_req->r_result < 0)
1752 obj_request->result = osd_req->r_result;
1754 rbd_assert(osd_req->r_num_ops <= CEPH_OSD_MAX_OP);
1757 * We support a 64-bit length, but ultimately it has to be
1758 * passed to blk_end_request(), which takes an unsigned int.
1760 obj_request->xferred = osd_req->r_reply_op_len[0];
1761 rbd_assert(obj_request->xferred < (u64)UINT_MAX);
1763 opcode = osd_req->r_ops[0].op;
1765 case CEPH_OSD_OP_READ:
1766 rbd_osd_read_callback(obj_request);
1768 case CEPH_OSD_OP_SETALLOCHINT:
1769 rbd_assert(osd_req->r_ops[1].op == CEPH_OSD_OP_WRITE);
1771 case CEPH_OSD_OP_WRITE:
1772 rbd_osd_write_callback(obj_request);
1774 case CEPH_OSD_OP_STAT:
1775 rbd_osd_stat_callback(obj_request);
1777 case CEPH_OSD_OP_CALL:
1778 case CEPH_OSD_OP_NOTIFY_ACK:
1779 case CEPH_OSD_OP_WATCH:
1780 rbd_osd_trivial_callback(obj_request);
1783 rbd_warn(NULL, "%s: unsupported op %hu\n",
1784 obj_request->object_name, (unsigned short) opcode);
1788 if (obj_request_done_test(obj_request))
1789 rbd_obj_request_complete(obj_request);
1792 static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request)
1794 struct rbd_img_request *img_request = obj_request->img_request;
1795 struct ceph_osd_request *osd_req = obj_request->osd_req;
1798 rbd_assert(osd_req != NULL);
1800 snap_id = img_request ? img_request->snap_id : CEPH_NOSNAP;
1801 ceph_osdc_build_request(osd_req, obj_request->offset,
1802 NULL, snap_id, NULL);
1805 static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request)
1807 struct rbd_img_request *img_request = obj_request->img_request;
1808 struct ceph_osd_request *osd_req = obj_request->osd_req;
1809 struct ceph_snap_context *snapc;
1810 struct timespec mtime = CURRENT_TIME;
1812 rbd_assert(osd_req != NULL);
1814 snapc = img_request ? img_request->snapc : NULL;
1815 ceph_osdc_build_request(osd_req, obj_request->offset,
1816 snapc, CEPH_NOSNAP, &mtime);
1820 * Create an osd request. A read request has one osd op (read).
1821 * A write request has either one (watch) or two (hint+write) osd ops.
1822 * (All rbd data writes are prefixed with an allocation hint op, but
1823 * technically osd watch is a write request, hence this distinction.)
1825 static struct ceph_osd_request *rbd_osd_req_create(
1826 struct rbd_device *rbd_dev,
1828 unsigned int num_ops,
1829 struct rbd_obj_request *obj_request)
1831 struct ceph_snap_context *snapc = NULL;
1832 struct ceph_osd_client *osdc;
1833 struct ceph_osd_request *osd_req;
1835 if (obj_request_img_data_test(obj_request)) {
1836 struct rbd_img_request *img_request = obj_request->img_request;
1838 rbd_assert(write_request ==
1839 img_request_write_test(img_request));
1841 snapc = img_request->snapc;
1844 rbd_assert(num_ops == 1 || (write_request && num_ops == 2));
1846 /* Allocate and initialize the request, for the num_ops ops */
1848 osdc = &rbd_dev->rbd_client->client->osdc;
1849 osd_req = ceph_osdc_alloc_request(osdc, snapc, num_ops, false,
1852 return NULL; /* ENOMEM */
1855 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1857 osd_req->r_flags = CEPH_OSD_FLAG_READ;
1859 osd_req->r_callback = rbd_osd_req_callback;
1860 osd_req->r_priv = obj_request;
1862 osd_req->r_base_oloc.pool = ceph_file_layout_pg_pool(rbd_dev->layout);
1863 ceph_oid_set_name(&osd_req->r_base_oid, obj_request->object_name);
1869 * Create a copyup osd request based on the information in the
1870 * object request supplied. A copyup request has three osd ops,
1871 * a copyup method call, a hint op, and a write op.
1873 static struct ceph_osd_request *
1874 rbd_osd_req_create_copyup(struct rbd_obj_request *obj_request)
1876 struct rbd_img_request *img_request;
1877 struct ceph_snap_context *snapc;
1878 struct rbd_device *rbd_dev;
1879 struct ceph_osd_client *osdc;
1880 struct ceph_osd_request *osd_req;
1882 rbd_assert(obj_request_img_data_test(obj_request));
1883 img_request = obj_request->img_request;
1884 rbd_assert(img_request);
1885 rbd_assert(img_request_write_test(img_request));
1887 /* Allocate and initialize the request, for the three ops */
1889 snapc = img_request->snapc;
1890 rbd_dev = img_request->rbd_dev;
1891 osdc = &rbd_dev->rbd_client->client->osdc;
1892 osd_req = ceph_osdc_alloc_request(osdc, snapc, 3, false, GFP_ATOMIC);
1894 return NULL; /* ENOMEM */
1896 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1897 osd_req->r_callback = rbd_osd_req_callback;
1898 osd_req->r_priv = obj_request;
1900 osd_req->r_base_oloc.pool = ceph_file_layout_pg_pool(rbd_dev->layout);
1901 ceph_oid_set_name(&osd_req->r_base_oid, obj_request->object_name);
1907 static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req)
1909 ceph_osdc_put_request(osd_req);
1912 /* object_name is assumed to be a non-null pointer and NUL-terminated */
1914 static struct rbd_obj_request *rbd_obj_request_create(const char *object_name,
1915 u64 offset, u64 length,
1916 enum obj_request_type type)
1918 struct rbd_obj_request *obj_request;
1922 rbd_assert(obj_request_type_valid(type));
1924 size = strlen(object_name) + 1;
1925 name = kmalloc(size, GFP_KERNEL);
1929 obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_KERNEL);
1935 obj_request->object_name = memcpy(name, object_name, size);
1936 obj_request->offset = offset;
1937 obj_request->length = length;
1938 obj_request->flags = 0;
1939 obj_request->which = BAD_WHICH;
1940 obj_request->type = type;
1941 INIT_LIST_HEAD(&obj_request->links);
1942 init_completion(&obj_request->completion);
1943 kref_init(&obj_request->kref);
1945 dout("%s: \"%s\" %llu/%llu %d -> obj %p\n", __func__, object_name,
1946 offset, length, (int)type, obj_request);
1951 static void rbd_obj_request_destroy(struct kref *kref)
1953 struct rbd_obj_request *obj_request;
1955 obj_request = container_of(kref, struct rbd_obj_request, kref);
1957 dout("%s: obj %p\n", __func__, obj_request);
1959 rbd_assert(obj_request->img_request == NULL);
1960 rbd_assert(obj_request->which == BAD_WHICH);
1962 if (obj_request->osd_req)
1963 rbd_osd_req_destroy(obj_request->osd_req);
1965 rbd_assert(obj_request_type_valid(obj_request->type));
1966 switch (obj_request->type) {
1967 case OBJ_REQUEST_NODATA:
1968 break; /* Nothing to do */
1969 case OBJ_REQUEST_BIO:
1970 if (obj_request->bio_list)
1971 bio_chain_put(obj_request->bio_list);
1973 case OBJ_REQUEST_PAGES:
1974 if (obj_request->pages)
1975 ceph_release_page_vector(obj_request->pages,
1976 obj_request->page_count);
1980 kfree(obj_request->object_name);
1981 obj_request->object_name = NULL;
1982 kmem_cache_free(rbd_obj_request_cache, obj_request);
1985 /* It's OK to call this for a device with no parent */
1987 static void rbd_spec_put(struct rbd_spec *spec);
1988 static void rbd_dev_unparent(struct rbd_device *rbd_dev)
1990 rbd_dev_remove_parent(rbd_dev);
1991 rbd_spec_put(rbd_dev->parent_spec);
1992 rbd_dev->parent_spec = NULL;
1993 rbd_dev->parent_overlap = 0;
1997 * Parent image reference counting is used to determine when an
1998 * image's parent fields can be safely torn down--after there are no
1999 * more in-flight requests to the parent image. When the last
2000 * reference is dropped, cleaning them up is safe.
2002 static void rbd_dev_parent_put(struct rbd_device *rbd_dev)
2006 if (!rbd_dev->parent_spec)
2009 counter = atomic_dec_return_safe(&rbd_dev->parent_ref);
2013 /* Last reference; clean up parent data structures */
2016 rbd_dev_unparent(rbd_dev);
2018 rbd_warn(rbd_dev, "parent reference underflow\n");
2022 * If an image has a non-zero parent overlap, get a reference to its
2025 * We must get the reference before checking for the overlap to
2026 * coordinate properly with zeroing the parent overlap in
2027 * rbd_dev_v2_parent_info() when an image gets flattened. We
2028 * drop it again if there is no overlap.
2030 * Returns true if the rbd device has a parent with a non-zero
2031 * overlap and a reference for it was successfully taken, or
2034 static bool rbd_dev_parent_get(struct rbd_device *rbd_dev)
2038 if (!rbd_dev->parent_spec)
2041 counter = atomic_inc_return_safe(&rbd_dev->parent_ref);
2042 if (counter > 0 && rbd_dev->parent_overlap)
2045 /* Image was flattened, but parent is not yet torn down */
2048 rbd_warn(rbd_dev, "parent reference overflow\n");
2054 * Caller is responsible for filling in the list of object requests
2055 * that comprises the image request, and the Linux request pointer
2056 * (if there is one).
2058 static struct rbd_img_request *rbd_img_request_create(
2059 struct rbd_device *rbd_dev,
2060 u64 offset, u64 length,
2063 struct rbd_img_request *img_request;
2065 img_request = kmem_cache_alloc(rbd_img_request_cache, GFP_ATOMIC);
2069 if (write_request) {
2070 down_read(&rbd_dev->header_rwsem);
2071 ceph_get_snap_context(rbd_dev->header.snapc);
2072 up_read(&rbd_dev->header_rwsem);
2075 img_request->rq = NULL;
2076 img_request->rbd_dev = rbd_dev;
2077 img_request->offset = offset;
2078 img_request->length = length;
2079 img_request->flags = 0;
2080 if (write_request) {
2081 img_request_write_set(img_request);
2082 img_request->snapc = rbd_dev->header.snapc;
2084 img_request->snap_id = rbd_dev->spec->snap_id;
2086 if (rbd_dev_parent_get(rbd_dev))
2087 img_request_layered_set(img_request);
2088 spin_lock_init(&img_request->completion_lock);
2089 img_request->next_completion = 0;
2090 img_request->callback = NULL;
2091 img_request->result = 0;
2092 img_request->obj_request_count = 0;
2093 INIT_LIST_HEAD(&img_request->obj_requests);
2094 kref_init(&img_request->kref);
2096 dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev,
2097 write_request ? "write" : "read", offset, length,
2103 static void rbd_img_request_destroy(struct kref *kref)
2105 struct rbd_img_request *img_request;
2106 struct rbd_obj_request *obj_request;
2107 struct rbd_obj_request *next_obj_request;
2109 img_request = container_of(kref, struct rbd_img_request, kref);
2111 dout("%s: img %p\n", __func__, img_request);
2113 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2114 rbd_img_obj_request_del(img_request, obj_request);
2115 rbd_assert(img_request->obj_request_count == 0);
2117 if (img_request_layered_test(img_request)) {
2118 img_request_layered_clear(img_request);
2119 rbd_dev_parent_put(img_request->rbd_dev);
2122 if (img_request_write_test(img_request))
2123 ceph_put_snap_context(img_request->snapc);
2125 kmem_cache_free(rbd_img_request_cache, img_request);
2128 static struct rbd_img_request *rbd_parent_request_create(
2129 struct rbd_obj_request *obj_request,
2130 u64 img_offset, u64 length)
2132 struct rbd_img_request *parent_request;
2133 struct rbd_device *rbd_dev;
2135 rbd_assert(obj_request->img_request);
2136 rbd_dev = obj_request->img_request->rbd_dev;
2138 parent_request = rbd_img_request_create(rbd_dev->parent,
2139 img_offset, length, false);
2140 if (!parent_request)
2143 img_request_child_set(parent_request);
2144 rbd_obj_request_get(obj_request);
2145 parent_request->obj_request = obj_request;
2147 return parent_request;
2150 static void rbd_parent_request_destroy(struct kref *kref)
2152 struct rbd_img_request *parent_request;
2153 struct rbd_obj_request *orig_request;
2155 parent_request = container_of(kref, struct rbd_img_request, kref);
2156 orig_request = parent_request->obj_request;
2158 parent_request->obj_request = NULL;
2159 rbd_obj_request_put(orig_request);
2160 img_request_child_clear(parent_request);
2162 rbd_img_request_destroy(kref);
2165 static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request)
2167 struct rbd_img_request *img_request;
2168 unsigned int xferred;
2172 rbd_assert(obj_request_img_data_test(obj_request));
2173 img_request = obj_request->img_request;
2175 rbd_assert(obj_request->xferred <= (u64)UINT_MAX);
2176 xferred = (unsigned int)obj_request->xferred;
2177 result = obj_request->result;
2179 struct rbd_device *rbd_dev = img_request->rbd_dev;
2181 rbd_warn(rbd_dev, "%s %llx at %llx (%llx)\n",
2182 img_request_write_test(img_request) ? "write" : "read",
2183 obj_request->length, obj_request->img_offset,
2184 obj_request->offset);
2185 rbd_warn(rbd_dev, " result %d xferred %x\n",
2187 if (!img_request->result)
2188 img_request->result = result;
2191 /* Image object requests don't own their page array */
2193 if (obj_request->type == OBJ_REQUEST_PAGES) {
2194 obj_request->pages = NULL;
2195 obj_request->page_count = 0;
2198 if (img_request_child_test(img_request)) {
2199 rbd_assert(img_request->obj_request != NULL);
2200 more = obj_request->which < img_request->obj_request_count - 1;
2202 rbd_assert(img_request->rq != NULL);
2203 more = blk_end_request(img_request->rq, result, xferred);
2209 static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
2211 struct rbd_img_request *img_request;
2212 u32 which = obj_request->which;
2215 rbd_assert(obj_request_img_data_test(obj_request));
2216 img_request = obj_request->img_request;
2218 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
2219 rbd_assert(img_request != NULL);
2220 rbd_assert(img_request->obj_request_count > 0);
2221 rbd_assert(which != BAD_WHICH);
2222 rbd_assert(which < img_request->obj_request_count);
2224 spin_lock_irq(&img_request->completion_lock);
2225 if (which != img_request->next_completion)
2228 for_each_obj_request_from(img_request, obj_request) {
2230 rbd_assert(which < img_request->obj_request_count);
2232 if (!obj_request_done_test(obj_request))
2234 more = rbd_img_obj_end_request(obj_request);
2238 rbd_assert(more ^ (which == img_request->obj_request_count));
2239 img_request->next_completion = which;
2241 spin_unlock_irq(&img_request->completion_lock);
2242 rbd_img_request_put(img_request);
2245 rbd_img_request_complete(img_request);
2249 * Split up an image request into one or more object requests, each
2250 * to a different object. The "type" parameter indicates whether
2251 * "data_desc" is the pointer to the head of a list of bio
2252 * structures, or the base of a page array. In either case this
2253 * function assumes data_desc describes memory sufficient to hold
2254 * all data described by the image request.
2256 static int rbd_img_request_fill(struct rbd_img_request *img_request,
2257 enum obj_request_type type,
2260 struct rbd_device *rbd_dev = img_request->rbd_dev;
2261 struct rbd_obj_request *obj_request = NULL;
2262 struct rbd_obj_request *next_obj_request;
2263 bool write_request = img_request_write_test(img_request);
2264 struct bio *bio_list = NULL;
2265 unsigned int bio_offset = 0;
2266 struct page **pages = NULL;
2271 dout("%s: img %p type %d data_desc %p\n", __func__, img_request,
2272 (int)type, data_desc);
2274 opcode = write_request ? CEPH_OSD_OP_WRITE : CEPH_OSD_OP_READ;
2275 img_offset = img_request->offset;
2276 resid = img_request->length;
2277 rbd_assert(resid > 0);
2279 if (type == OBJ_REQUEST_BIO) {
2280 bio_list = data_desc;
2281 rbd_assert(img_offset ==
2282 bio_list->bi_iter.bi_sector << SECTOR_SHIFT);
2284 rbd_assert(type == OBJ_REQUEST_PAGES);
2289 struct ceph_osd_request *osd_req;
2290 const char *object_name;
2293 unsigned int which = 0;
2295 object_name = rbd_segment_name(rbd_dev, img_offset);
2298 offset = rbd_segment_offset(rbd_dev, img_offset);
2299 length = rbd_segment_length(rbd_dev, img_offset, resid);
2300 obj_request = rbd_obj_request_create(object_name,
2301 offset, length, type);
2302 /* object request has its own copy of the object name */
2303 rbd_segment_name_free(object_name);
2308 * set obj_request->img_request before creating the
2309 * osd_request so that it gets the right snapc
2311 rbd_img_obj_request_add(img_request, obj_request);
2313 if (type == OBJ_REQUEST_BIO) {
2314 unsigned int clone_size;
2316 rbd_assert(length <= (u64)UINT_MAX);
2317 clone_size = (unsigned int)length;
2318 obj_request->bio_list =
2319 bio_chain_clone_range(&bio_list,
2323 if (!obj_request->bio_list)
2326 unsigned int page_count;
2328 obj_request->pages = pages;
2329 page_count = (u32)calc_pages_for(offset, length);
2330 obj_request->page_count = page_count;
2331 if ((offset + length) & ~PAGE_MASK)
2332 page_count--; /* more on last page */
2333 pages += page_count;
2336 osd_req = rbd_osd_req_create(rbd_dev, write_request,
2337 (write_request ? 2 : 1),
2341 obj_request->osd_req = osd_req;
2342 obj_request->callback = rbd_img_obj_callback;
2343 rbd_img_request_get(img_request);
2345 if (write_request) {
2346 osd_req_op_alloc_hint_init(osd_req, which,
2347 rbd_obj_bytes(&rbd_dev->header),
2348 rbd_obj_bytes(&rbd_dev->header));
2352 osd_req_op_extent_init(osd_req, which, opcode, offset, length,
2354 if (type == OBJ_REQUEST_BIO)
2355 osd_req_op_extent_osd_data_bio(osd_req, which,
2356 obj_request->bio_list, length);
2358 osd_req_op_extent_osd_data_pages(osd_req, which,
2359 obj_request->pages, length,
2360 offset & ~PAGE_MASK, false, false);
2363 rbd_osd_req_format_write(obj_request);
2365 rbd_osd_req_format_read(obj_request);
2367 obj_request->img_offset = img_offset;
2369 img_offset += length;
2376 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2377 rbd_img_obj_request_del(img_request, obj_request);
2383 rbd_img_obj_copyup_callback(struct rbd_obj_request *obj_request)
2385 struct rbd_img_request *img_request;
2386 struct rbd_device *rbd_dev;
2387 struct page **pages;
2390 rbd_assert(obj_request->type == OBJ_REQUEST_BIO);
2391 rbd_assert(obj_request_img_data_test(obj_request));
2392 img_request = obj_request->img_request;
2393 rbd_assert(img_request);
2395 rbd_dev = img_request->rbd_dev;
2396 rbd_assert(rbd_dev);
2398 pages = obj_request->copyup_pages;
2399 rbd_assert(pages != NULL);
2400 obj_request->copyup_pages = NULL;
2401 page_count = obj_request->copyup_page_count;
2402 rbd_assert(page_count);
2403 obj_request->copyup_page_count = 0;
2404 ceph_release_page_vector(pages, page_count);
2407 * We want the transfer count to reflect the size of the
2408 * original write request. There is no such thing as a
2409 * successful short write, so if the request was successful
2410 * we can just set it to the originally-requested length.
2412 if (!obj_request->result)
2413 obj_request->xferred = obj_request->length;
2415 /* Finish up with the normal image object callback */
2417 rbd_img_obj_callback(obj_request);
2421 rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request)
2423 struct rbd_obj_request *orig_request;
2424 struct ceph_osd_request *osd_req;
2425 struct ceph_osd_client *osdc;
2426 struct rbd_device *rbd_dev;
2427 struct page **pages;
2434 rbd_assert(img_request_child_test(img_request));
2436 /* First get what we need from the image request */
2438 pages = img_request->copyup_pages;
2439 rbd_assert(pages != NULL);
2440 img_request->copyup_pages = NULL;
2441 page_count = img_request->copyup_page_count;
2442 rbd_assert(page_count);
2443 img_request->copyup_page_count = 0;
2445 orig_request = img_request->obj_request;
2446 rbd_assert(orig_request != NULL);
2447 rbd_assert(obj_request_type_valid(orig_request->type));
2448 img_result = img_request->result;
2449 parent_length = img_request->length;
2450 rbd_assert(parent_length == img_request->xferred);
2451 rbd_img_request_put(img_request);
2453 rbd_assert(orig_request->img_request);
2454 rbd_dev = orig_request->img_request->rbd_dev;
2455 rbd_assert(rbd_dev);
2458 * If the overlap has become 0 (most likely because the
2459 * image has been flattened) we need to free the pages
2460 * and re-submit the original write request.
2462 if (!rbd_dev->parent_overlap) {
2463 struct ceph_osd_client *osdc;
2465 ceph_release_page_vector(pages, page_count);
2466 osdc = &rbd_dev->rbd_client->client->osdc;
2467 img_result = rbd_obj_request_submit(osdc, orig_request);
2476 * The original osd request is of no use to use any more.
2477 * We need a new one that can hold the three ops in a copyup
2478 * request. Allocate the new copyup osd request for the
2479 * original request, and release the old one.
2481 img_result = -ENOMEM;
2482 osd_req = rbd_osd_req_create_copyup(orig_request);
2485 rbd_osd_req_destroy(orig_request->osd_req);
2486 orig_request->osd_req = osd_req;
2487 orig_request->copyup_pages = pages;
2488 orig_request->copyup_page_count = page_count;
2490 /* Initialize the copyup op */
2492 osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup");
2493 osd_req_op_cls_request_data_pages(osd_req, 0, pages, parent_length, 0,
2496 /* Then the hint op */
2498 osd_req_op_alloc_hint_init(osd_req, 1, rbd_obj_bytes(&rbd_dev->header),
2499 rbd_obj_bytes(&rbd_dev->header));
2501 /* And the original write request op */
2503 offset = orig_request->offset;
2504 length = orig_request->length;
2505 osd_req_op_extent_init(osd_req, 2, CEPH_OSD_OP_WRITE,
2506 offset, length, 0, 0);
2507 if (orig_request->type == OBJ_REQUEST_BIO)
2508 osd_req_op_extent_osd_data_bio(osd_req, 2,
2509 orig_request->bio_list, length);
2511 osd_req_op_extent_osd_data_pages(osd_req, 2,
2512 orig_request->pages, length,
2513 offset & ~PAGE_MASK, false, false);
2515 rbd_osd_req_format_write(orig_request);
2517 /* All set, send it off. */
2519 orig_request->callback = rbd_img_obj_copyup_callback;
2520 osdc = &rbd_dev->rbd_client->client->osdc;
2521 img_result = rbd_obj_request_submit(osdc, orig_request);
2525 /* Record the error code and complete the request */
2527 orig_request->result = img_result;
2528 orig_request->xferred = 0;
2529 obj_request_done_set(orig_request);
2530 rbd_obj_request_complete(orig_request);
2534 * Read from the parent image the range of data that covers the
2535 * entire target of the given object request. This is used for
2536 * satisfying a layered image write request when the target of an
2537 * object request from the image request does not exist.
2539 * A page array big enough to hold the returned data is allocated
2540 * and supplied to rbd_img_request_fill() as the "data descriptor."
2541 * When the read completes, this page array will be transferred to
2542 * the original object request for the copyup operation.
2544 * If an error occurs, record it as the result of the original
2545 * object request and mark it done so it gets completed.
2547 static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request)
2549 struct rbd_img_request *img_request = NULL;
2550 struct rbd_img_request *parent_request = NULL;
2551 struct rbd_device *rbd_dev;
2554 struct page **pages = NULL;
2558 rbd_assert(obj_request_img_data_test(obj_request));
2559 rbd_assert(obj_request_type_valid(obj_request->type));
2561 img_request = obj_request->img_request;
2562 rbd_assert(img_request != NULL);
2563 rbd_dev = img_request->rbd_dev;
2564 rbd_assert(rbd_dev->parent != NULL);
2567 * Determine the byte range covered by the object in the
2568 * child image to which the original request was to be sent.
2570 img_offset = obj_request->img_offset - obj_request->offset;
2571 length = (u64)1 << rbd_dev->header.obj_order;
2574 * There is no defined parent data beyond the parent
2575 * overlap, so limit what we read at that boundary if
2578 if (img_offset + length > rbd_dev->parent_overlap) {
2579 rbd_assert(img_offset < rbd_dev->parent_overlap);
2580 length = rbd_dev->parent_overlap - img_offset;
2584 * Allocate a page array big enough to receive the data read
2587 page_count = (u32)calc_pages_for(0, length);
2588 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2589 if (IS_ERR(pages)) {
2590 result = PTR_ERR(pages);
2596 parent_request = rbd_parent_request_create(obj_request,
2597 img_offset, length);
2598 if (!parent_request)
2601 result = rbd_img_request_fill(parent_request, OBJ_REQUEST_PAGES, pages);
2604 parent_request->copyup_pages = pages;
2605 parent_request->copyup_page_count = page_count;
2607 parent_request->callback = rbd_img_obj_parent_read_full_callback;
2608 result = rbd_img_request_submit(parent_request);
2612 parent_request->copyup_pages = NULL;
2613 parent_request->copyup_page_count = 0;
2614 parent_request->obj_request = NULL;
2615 rbd_obj_request_put(obj_request);
2618 ceph_release_page_vector(pages, page_count);
2620 rbd_img_request_put(parent_request);
2621 obj_request->result = result;
2622 obj_request->xferred = 0;
2623 obj_request_done_set(obj_request);
2628 static void rbd_img_obj_exists_callback(struct rbd_obj_request *obj_request)
2630 struct rbd_obj_request *orig_request;
2631 struct rbd_device *rbd_dev;
2634 rbd_assert(!obj_request_img_data_test(obj_request));
2637 * All we need from the object request is the original
2638 * request and the result of the STAT op. Grab those, then
2639 * we're done with the request.
2641 orig_request = obj_request->obj_request;
2642 obj_request->obj_request = NULL;
2643 rbd_obj_request_put(orig_request);
2644 rbd_assert(orig_request);
2645 rbd_assert(orig_request->img_request);
2647 result = obj_request->result;
2648 obj_request->result = 0;
2650 dout("%s: obj %p for obj %p result %d %llu/%llu\n", __func__,
2651 obj_request, orig_request, result,
2652 obj_request->xferred, obj_request->length);
2653 rbd_obj_request_put(obj_request);
2656 * If the overlap has become 0 (most likely because the
2657 * image has been flattened) we need to free the pages
2658 * and re-submit the original write request.
2660 rbd_dev = orig_request->img_request->rbd_dev;
2661 if (!rbd_dev->parent_overlap) {
2662 struct ceph_osd_client *osdc;
2664 osdc = &rbd_dev->rbd_client->client->osdc;
2665 result = rbd_obj_request_submit(osdc, orig_request);
2671 * Our only purpose here is to determine whether the object
2672 * exists, and we don't want to treat the non-existence as
2673 * an error. If something else comes back, transfer the
2674 * error to the original request and complete it now.
2677 obj_request_existence_set(orig_request, true);
2678 } else if (result == -ENOENT) {
2679 obj_request_existence_set(orig_request, false);
2680 } else if (result) {
2681 orig_request->result = result;
2686 * Resubmit the original request now that we have recorded
2687 * whether the target object exists.
2689 orig_request->result = rbd_img_obj_request_submit(orig_request);
2691 if (orig_request->result)
2692 rbd_obj_request_complete(orig_request);
2695 static int rbd_img_obj_exists_submit(struct rbd_obj_request *obj_request)
2697 struct rbd_obj_request *stat_request;
2698 struct rbd_device *rbd_dev;
2699 struct ceph_osd_client *osdc;
2700 struct page **pages = NULL;
2706 * The response data for a STAT call consists of:
2713 size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32);
2714 page_count = (u32)calc_pages_for(0, size);
2715 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2717 return PTR_ERR(pages);
2720 stat_request = rbd_obj_request_create(obj_request->object_name, 0, 0,
2725 rbd_obj_request_get(obj_request);
2726 stat_request->obj_request = obj_request;
2727 stat_request->pages = pages;
2728 stat_request->page_count = page_count;
2730 rbd_assert(obj_request->img_request);
2731 rbd_dev = obj_request->img_request->rbd_dev;
2732 stat_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1,
2734 if (!stat_request->osd_req)
2736 stat_request->callback = rbd_img_obj_exists_callback;
2738 osd_req_op_init(stat_request->osd_req, 0, CEPH_OSD_OP_STAT);
2739 osd_req_op_raw_data_in_pages(stat_request->osd_req, 0, pages, size, 0,
2741 rbd_osd_req_format_read(stat_request);
2743 osdc = &rbd_dev->rbd_client->client->osdc;
2744 ret = rbd_obj_request_submit(osdc, stat_request);
2747 rbd_obj_request_put(obj_request);
2752 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request)
2754 struct rbd_img_request *img_request;
2755 struct rbd_device *rbd_dev;
2758 rbd_assert(obj_request_img_data_test(obj_request));
2760 img_request = obj_request->img_request;
2761 rbd_assert(img_request);
2762 rbd_dev = img_request->rbd_dev;
2765 * Only writes to layered images need special handling.
2766 * Reads and non-layered writes are simple object requests.
2767 * Layered writes that start beyond the end of the overlap
2768 * with the parent have no parent data, so they too are
2769 * simple object requests. Finally, if the target object is
2770 * known to already exist, its parent data has already been
2771 * copied, so a write to the object can also be handled as a
2772 * simple object request.
2774 if (!img_request_write_test(img_request) ||
2775 !img_request_layered_test(img_request) ||
2776 !obj_request_overlaps_parent(obj_request) ||
2777 ((known = obj_request_known_test(obj_request)) &&
2778 obj_request_exists_test(obj_request))) {
2780 struct rbd_device *rbd_dev;
2781 struct ceph_osd_client *osdc;
2783 rbd_dev = obj_request->img_request->rbd_dev;
2784 osdc = &rbd_dev->rbd_client->client->osdc;
2786 return rbd_obj_request_submit(osdc, obj_request);
2790 * It's a layered write. The target object might exist but
2791 * we may not know that yet. If we know it doesn't exist,
2792 * start by reading the data for the full target object from
2793 * the parent so we can use it for a copyup to the target.
2796 return rbd_img_obj_parent_read_full(obj_request);
2798 /* We don't know whether the target exists. Go find out. */
2800 return rbd_img_obj_exists_submit(obj_request);
2803 static int rbd_img_request_submit(struct rbd_img_request *img_request)
2805 struct rbd_obj_request *obj_request;
2806 struct rbd_obj_request *next_obj_request;
2808 dout("%s: img %p\n", __func__, img_request);
2809 for_each_obj_request_safe(img_request, obj_request, next_obj_request) {
2812 ret = rbd_img_obj_request_submit(obj_request);
2820 static void rbd_img_parent_read_callback(struct rbd_img_request *img_request)
2822 struct rbd_obj_request *obj_request;
2823 struct rbd_device *rbd_dev;
2828 rbd_assert(img_request_child_test(img_request));
2830 /* First get what we need from the image request and release it */
2832 obj_request = img_request->obj_request;
2833 img_xferred = img_request->xferred;
2834 img_result = img_request->result;
2835 rbd_img_request_put(img_request);
2838 * If the overlap has become 0 (most likely because the
2839 * image has been flattened) we need to re-submit the
2842 rbd_assert(obj_request);
2843 rbd_assert(obj_request->img_request);
2844 rbd_dev = obj_request->img_request->rbd_dev;
2845 if (!rbd_dev->parent_overlap) {
2846 struct ceph_osd_client *osdc;
2848 osdc = &rbd_dev->rbd_client->client->osdc;
2849 img_result = rbd_obj_request_submit(osdc, obj_request);
2854 obj_request->result = img_result;
2855 if (obj_request->result)
2859 * We need to zero anything beyond the parent overlap
2860 * boundary. Since rbd_img_obj_request_read_callback()
2861 * will zero anything beyond the end of a short read, an
2862 * easy way to do this is to pretend the data from the
2863 * parent came up short--ending at the overlap boundary.
2865 rbd_assert(obj_request->img_offset < U64_MAX - obj_request->length);
2866 obj_end = obj_request->img_offset + obj_request->length;
2867 if (obj_end > rbd_dev->parent_overlap) {
2870 if (obj_request->img_offset < rbd_dev->parent_overlap)
2871 xferred = rbd_dev->parent_overlap -
2872 obj_request->img_offset;
2874 obj_request->xferred = min(img_xferred, xferred);
2876 obj_request->xferred = img_xferred;
2879 rbd_img_obj_request_read_callback(obj_request);
2880 rbd_obj_request_complete(obj_request);
2883 static void rbd_img_parent_read(struct rbd_obj_request *obj_request)
2885 struct rbd_img_request *img_request;
2888 rbd_assert(obj_request_img_data_test(obj_request));
2889 rbd_assert(obj_request->img_request != NULL);
2890 rbd_assert(obj_request->result == (s32) -ENOENT);
2891 rbd_assert(obj_request_type_valid(obj_request->type));
2893 /* rbd_read_finish(obj_request, obj_request->length); */
2894 img_request = rbd_parent_request_create(obj_request,
2895 obj_request->img_offset,
2896 obj_request->length);
2901 if (obj_request->type == OBJ_REQUEST_BIO)
2902 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
2903 obj_request->bio_list);
2905 result = rbd_img_request_fill(img_request, OBJ_REQUEST_PAGES,
2906 obj_request->pages);
2910 img_request->callback = rbd_img_parent_read_callback;
2911 result = rbd_img_request_submit(img_request);
2918 rbd_img_request_put(img_request);
2919 obj_request->result = result;
2920 obj_request->xferred = 0;
2921 obj_request_done_set(obj_request);
2924 static int rbd_obj_notify_ack_sync(struct rbd_device *rbd_dev, u64 notify_id)
2926 struct rbd_obj_request *obj_request;
2927 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2930 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
2931 OBJ_REQUEST_NODATA);
2936 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1,
2938 if (!obj_request->osd_req)
2941 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK,
2943 rbd_osd_req_format_read(obj_request);
2945 ret = rbd_obj_request_submit(osdc, obj_request);
2948 ret = rbd_obj_request_wait(obj_request);
2950 rbd_obj_request_put(obj_request);
2955 static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
2957 struct rbd_device *rbd_dev = (struct rbd_device *)data;
2963 dout("%s: \"%s\" notify_id %llu opcode %u\n", __func__,
2964 rbd_dev->header_name, (unsigned long long)notify_id,
2965 (unsigned int)opcode);
2966 ret = rbd_dev_refresh(rbd_dev);
2968 rbd_warn(rbd_dev, "header refresh error (%d)\n", ret);
2970 rbd_obj_notify_ack_sync(rbd_dev, notify_id);
2974 * Send a (un)watch request and wait for the ack. Return a request
2975 * with a ref held on success or error.
2977 static struct rbd_obj_request *rbd_obj_watch_request_helper(
2978 struct rbd_device *rbd_dev,
2981 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2982 struct rbd_obj_request *obj_request;
2985 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
2986 OBJ_REQUEST_NODATA);
2988 return ERR_PTR(-ENOMEM);
2990 obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, 1,
2992 if (!obj_request->osd_req) {
2997 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
2998 rbd_dev->watch_event->cookie, 0, watch);
2999 rbd_osd_req_format_write(obj_request);
3002 ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
3004 ret = rbd_obj_request_submit(osdc, obj_request);
3008 ret = rbd_obj_request_wait(obj_request);
3012 ret = obj_request->result;
3015 rbd_obj_request_end(obj_request);
3022 rbd_obj_request_put(obj_request);
3023 return ERR_PTR(ret);
3027 * Initiate a watch request, synchronously.
3029 static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev)
3031 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3032 struct rbd_obj_request *obj_request;
3035 rbd_assert(!rbd_dev->watch_event);
3036 rbd_assert(!rbd_dev->watch_request);
3038 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
3039 &rbd_dev->watch_event);
3043 obj_request = rbd_obj_watch_request_helper(rbd_dev, true);
3044 if (IS_ERR(obj_request)) {
3045 ceph_osdc_cancel_event(rbd_dev->watch_event);
3046 rbd_dev->watch_event = NULL;
3047 return PTR_ERR(obj_request);
3051 * A watch request is set to linger, so the underlying osd
3052 * request won't go away until we unregister it. We retain
3053 * a pointer to the object request during that time (in
3054 * rbd_dev->watch_request), so we'll keep a reference to it.
3055 * We'll drop that reference after we've unregistered it in
3056 * rbd_dev_header_unwatch_sync().
3058 rbd_dev->watch_request = obj_request;
3064 * Tear down a watch request, synchronously.
3066 static void rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev)
3068 struct rbd_obj_request *obj_request;
3070 rbd_assert(rbd_dev->watch_event);
3071 rbd_assert(rbd_dev->watch_request);
3073 rbd_obj_request_end(rbd_dev->watch_request);
3074 rbd_obj_request_put(rbd_dev->watch_request);
3075 rbd_dev->watch_request = NULL;
3077 obj_request = rbd_obj_watch_request_helper(rbd_dev, false);
3078 if (!IS_ERR(obj_request))
3079 rbd_obj_request_put(obj_request);
3081 rbd_warn(rbd_dev, "unable to tear down watch request (%ld)",
3082 PTR_ERR(obj_request));
3084 ceph_osdc_cancel_event(rbd_dev->watch_event);
3085 rbd_dev->watch_event = NULL;
3089 * Synchronous osd object method call. Returns the number of bytes
3090 * returned in the outbound buffer, or a negative error code.
3092 static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
3093 const char *object_name,
3094 const char *class_name,
3095 const char *method_name,
3096 const void *outbound,
3097 size_t outbound_size,
3099 size_t inbound_size)
3101 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3102 struct rbd_obj_request *obj_request;
3103 struct page **pages;
3108 * Method calls are ultimately read operations. The result
3109 * should placed into the inbound buffer provided. They
3110 * also supply outbound data--parameters for the object
3111 * method. Currently if this is present it will be a
3114 page_count = (u32)calc_pages_for(0, inbound_size);
3115 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
3117 return PTR_ERR(pages);
3120 obj_request = rbd_obj_request_create(object_name, 0, inbound_size,
3125 obj_request->pages = pages;
3126 obj_request->page_count = page_count;
3128 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1,
3130 if (!obj_request->osd_req)
3133 osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL,
3134 class_name, method_name);
3135 if (outbound_size) {
3136 struct ceph_pagelist *pagelist;
3138 pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS);
3142 ceph_pagelist_init(pagelist);
3143 ceph_pagelist_append(pagelist, outbound, outbound_size);
3144 osd_req_op_cls_request_data_pagelist(obj_request->osd_req, 0,
3147 osd_req_op_cls_response_data_pages(obj_request->osd_req, 0,
3148 obj_request->pages, inbound_size,
3150 rbd_osd_req_format_read(obj_request);
3152 ret = rbd_obj_request_submit(osdc, obj_request);
3155 ret = rbd_obj_request_wait(obj_request);
3159 ret = obj_request->result;
3163 rbd_assert(obj_request->xferred < (u64)INT_MAX);
3164 ret = (int)obj_request->xferred;
3165 ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred);
3168 rbd_obj_request_put(obj_request);
3170 ceph_release_page_vector(pages, page_count);
3175 static void rbd_request_fn(struct request_queue *q)
3176 __releases(q->queue_lock) __acquires(q->queue_lock)
3178 struct rbd_device *rbd_dev = q->queuedata;
3182 while ((rq = blk_fetch_request(q))) {
3183 bool write_request = rq_data_dir(rq) == WRITE;
3184 struct rbd_img_request *img_request;
3188 /* Ignore any non-FS requests that filter through. */
3190 if (rq->cmd_type != REQ_TYPE_FS) {
3191 dout("%s: non-fs request type %d\n", __func__,
3192 (int) rq->cmd_type);
3193 __blk_end_request_all(rq, 0);
3197 /* Ignore/skip any zero-length requests */
3199 offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT;
3200 length = (u64) blk_rq_bytes(rq);
3203 dout("%s: zero-length request\n", __func__);
3204 __blk_end_request_all(rq, 0);
3208 spin_unlock_irq(q->queue_lock);
3210 /* Disallow writes to a read-only device */
3212 if (write_request) {
3214 if (rbd_dev->mapping.read_only)
3216 rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP);
3220 * Quit early if the mapped snapshot no longer
3221 * exists. It's still possible the snapshot will
3222 * have disappeared by the time our request arrives
3223 * at the osd, but there's no sense in sending it if
3226 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) {
3227 dout("request for non-existent snapshot");
3228 rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP);
3234 if (offset && length > U64_MAX - offset + 1) {
3235 rbd_warn(rbd_dev, "bad request range (%llu~%llu)\n",
3237 goto end_request; /* Shouldn't happen */
3241 if (offset + length > rbd_dev->mapping.size) {
3242 rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)\n",
3243 offset, length, rbd_dev->mapping.size);
3248 img_request = rbd_img_request_create(rbd_dev, offset, length,
3253 img_request->rq = rq;
3255 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
3258 result = rbd_img_request_submit(img_request);
3260 rbd_img_request_put(img_request);
3262 spin_lock_irq(q->queue_lock);
3264 rbd_warn(rbd_dev, "%s %llx at %llx result %d\n",
3265 write_request ? "write" : "read",
3266 length, offset, result);
3268 __blk_end_request_all(rq, result);
3274 * a queue callback. Makes sure that we don't create a bio that spans across
3275 * multiple osd objects. One exception would be with a single page bios,
3276 * which we handle later at bio_chain_clone_range()
3278 static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
3279 struct bio_vec *bvec)
3281 struct rbd_device *rbd_dev = q->queuedata;
3282 sector_t sector_offset;
3283 sector_t sectors_per_obj;
3284 sector_t obj_sector_offset;
3288 * Find how far into its rbd object the partition-relative
3289 * bio start sector is to offset relative to the enclosing
3292 sector_offset = get_start_sect(bmd->bi_bdev) + bmd->bi_sector;
3293 sectors_per_obj = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT);
3294 obj_sector_offset = sector_offset & (sectors_per_obj - 1);
3297 * Compute the number of bytes from that offset to the end
3298 * of the object. Account for what's already used by the bio.
3300 ret = (int) (sectors_per_obj - obj_sector_offset) << SECTOR_SHIFT;
3301 if (ret > bmd->bi_size)
3302 ret -= bmd->bi_size;
3307 * Don't send back more than was asked for. And if the bio
3308 * was empty, let the whole thing through because: "Note
3309 * that a block device *must* allow a single page to be
3310 * added to an empty bio."
3312 rbd_assert(bvec->bv_len <= PAGE_SIZE);
3313 if (ret > (int) bvec->bv_len || !bmd->bi_size)
3314 ret = (int) bvec->bv_len;
3319 static void rbd_free_disk(struct rbd_device *rbd_dev)
3321 struct gendisk *disk = rbd_dev->disk;
3326 rbd_dev->disk = NULL;
3327 if (disk->flags & GENHD_FL_UP) {
3330 blk_cleanup_queue(disk->queue);
3335 static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
3336 const char *object_name,
3337 u64 offset, u64 length, void *buf)
3340 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3341 struct rbd_obj_request *obj_request;
3342 struct page **pages = NULL;
3347 page_count = (u32) calc_pages_for(offset, length);
3348 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
3350 ret = PTR_ERR(pages);
3353 obj_request = rbd_obj_request_create(object_name, offset, length,
3358 obj_request->pages = pages;
3359 obj_request->page_count = page_count;
3361 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1,
3363 if (!obj_request->osd_req)
3366 osd_req_op_extent_init(obj_request->osd_req, 0, CEPH_OSD_OP_READ,
3367 offset, length, 0, 0);
3368 osd_req_op_extent_osd_data_pages(obj_request->osd_req, 0,
3370 obj_request->length,
3371 obj_request->offset & ~PAGE_MASK,
3373 rbd_osd_req_format_read(obj_request);
3375 ret = rbd_obj_request_submit(osdc, obj_request);
3378 ret = rbd_obj_request_wait(obj_request);
3382 ret = obj_request->result;
3386 rbd_assert(obj_request->xferred <= (u64) SIZE_MAX);
3387 size = (size_t) obj_request->xferred;
3388 ceph_copy_from_page_vector(pages, buf, 0, size);
3389 rbd_assert(size <= (size_t)INT_MAX);
3393 rbd_obj_request_put(obj_request);
3395 ceph_release_page_vector(pages, page_count);
3401 * Read the complete header for the given rbd device. On successful
3402 * return, the rbd_dev->header field will contain up-to-date
3403 * information about the image.
3405 static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
3407 struct rbd_image_header_ondisk *ondisk = NULL;
3414 * The complete header will include an array of its 64-bit
3415 * snapshot ids, followed by the names of those snapshots as
3416 * a contiguous block of NUL-terminated strings. Note that
3417 * the number of snapshots could change by the time we read
3418 * it in, in which case we re-read it.
3425 size = sizeof (*ondisk);
3426 size += snap_count * sizeof (struct rbd_image_snap_ondisk);
3428 ondisk = kmalloc(size, GFP_KERNEL);
3432 ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name,
3436 if ((size_t)ret < size) {
3438 rbd_warn(rbd_dev, "short header read (want %zd got %d)",
3442 if (!rbd_dev_ondisk_valid(ondisk)) {
3444 rbd_warn(rbd_dev, "invalid header");
3448 names_size = le64_to_cpu(ondisk->snap_names_len);
3449 want_count = snap_count;
3450 snap_count = le32_to_cpu(ondisk->snap_count);
3451 } while (snap_count != want_count);
3453 ret = rbd_header_from_disk(rbd_dev, ondisk);
3461 * Clear the rbd device's EXISTS flag if the snapshot it's mapped to
3462 * has disappeared from the (just updated) snapshot context.
3464 static void rbd_exists_validate(struct rbd_device *rbd_dev)
3468 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags))
3471 snap_id = rbd_dev->spec->snap_id;
3472 if (snap_id == CEPH_NOSNAP)
3475 if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX)
3476 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
3479 static void rbd_dev_update_size(struct rbd_device *rbd_dev)
3485 * Don't hold the lock while doing disk operations,
3486 * or lock ordering will conflict with the bdev mutex via:
3487 * rbd_add() -> blkdev_get() -> rbd_open()
3489 spin_lock_irq(&rbd_dev->lock);
3490 removing = test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags);
3491 spin_unlock_irq(&rbd_dev->lock);
3493 * If the device is being removed, rbd_dev->disk has
3494 * been destroyed, so don't try to update its size
3497 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
3498 dout("setting size to %llu sectors", (unsigned long long)size);
3499 set_capacity(rbd_dev->disk, size);
3500 revalidate_disk(rbd_dev->disk);
3504 static int rbd_dev_refresh(struct rbd_device *rbd_dev)
3509 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
3510 down_write(&rbd_dev->header_rwsem);
3511 mapping_size = rbd_dev->mapping.size;
3512 if (rbd_dev->image_format == 1)
3513 ret = rbd_dev_v1_header_info(rbd_dev);
3515 ret = rbd_dev_v2_header_info(rbd_dev);
3517 /* If it's a mapped snapshot, validate its EXISTS flag */
3519 rbd_exists_validate(rbd_dev);
3520 up_write(&rbd_dev->header_rwsem);
3522 if (mapping_size != rbd_dev->mapping.size) {
3523 rbd_dev_update_size(rbd_dev);
3529 static int rbd_init_disk(struct rbd_device *rbd_dev)
3531 struct gendisk *disk;
3532 struct request_queue *q;
3535 /* create gendisk info */
3536 disk = alloc_disk(single_major ?
3537 (1 << RBD_SINGLE_MAJOR_PART_SHIFT) :
3538 RBD_MINORS_PER_MAJOR);
3542 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
3544 disk->major = rbd_dev->major;
3545 disk->first_minor = rbd_dev->minor;
3547 disk->flags |= GENHD_FL_EXT_DEVT;
3548 disk->fops = &rbd_bd_ops;
3549 disk->private_data = rbd_dev;
3551 q = blk_init_queue(rbd_request_fn, &rbd_dev->lock);
3555 /* We use the default size, but let's be explicit about it. */
3556 blk_queue_physical_block_size(q, SECTOR_SIZE);
3558 /* set io sizes to object size */
3559 segment_size = rbd_obj_bytes(&rbd_dev->header);
3560 blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
3561 blk_queue_max_segment_size(q, segment_size);
3562 blk_queue_io_min(q, segment_size);
3563 blk_queue_io_opt(q, segment_size);
3565 blk_queue_merge_bvec(q, rbd_merge_bvec);
3568 q->queuedata = rbd_dev;
3570 rbd_dev->disk = disk;
3583 static struct rbd_device *dev_to_rbd_dev(struct device *dev)
3585 return container_of(dev, struct rbd_device, dev);
3588 static ssize_t rbd_size_show(struct device *dev,
3589 struct device_attribute *attr, char *buf)
3591 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3593 return sprintf(buf, "%llu\n",
3594 (unsigned long long)rbd_dev->mapping.size);
3598 * Note this shows the features for whatever's mapped, which is not
3599 * necessarily the base image.
3601 static ssize_t rbd_features_show(struct device *dev,
3602 struct device_attribute *attr, char *buf)
3604 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3606 return sprintf(buf, "0x%016llx\n",
3607 (unsigned long long)rbd_dev->mapping.features);
3610 static ssize_t rbd_major_show(struct device *dev,
3611 struct device_attribute *attr, char *buf)
3613 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3616 return sprintf(buf, "%d\n", rbd_dev->major);
3618 return sprintf(buf, "(none)\n");
3621 static ssize_t rbd_minor_show(struct device *dev,
3622 struct device_attribute *attr, char *buf)
3624 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3626 return sprintf(buf, "%d\n", rbd_dev->minor);
3629 static ssize_t rbd_client_id_show(struct device *dev,
3630 struct device_attribute *attr, char *buf)
3632 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3634 return sprintf(buf, "client%lld\n",
3635 ceph_client_id(rbd_dev->rbd_client->client));
3638 static ssize_t rbd_pool_show(struct device *dev,
3639 struct device_attribute *attr, char *buf)
3641 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3643 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
3646 static ssize_t rbd_pool_id_show(struct device *dev,
3647 struct device_attribute *attr, char *buf)
3649 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3651 return sprintf(buf, "%llu\n",
3652 (unsigned long long) rbd_dev->spec->pool_id);
3655 static ssize_t rbd_name_show(struct device *dev,
3656 struct device_attribute *attr, char *buf)
3658 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3660 if (rbd_dev->spec->image_name)
3661 return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
3663 return sprintf(buf, "(unknown)\n");
3666 static ssize_t rbd_image_id_show(struct device *dev,
3667 struct device_attribute *attr, char *buf)
3669 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3671 return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
3675 * Shows the name of the currently-mapped snapshot (or
3676 * RBD_SNAP_HEAD_NAME for the base image).
3678 static ssize_t rbd_snap_show(struct device *dev,
3679 struct device_attribute *attr,
3682 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3684 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
3688 * For an rbd v2 image, shows the pool id, image id, and snapshot id
3689 * for the parent image. If there is no parent, simply shows
3690 * "(no parent image)".
3692 static ssize_t rbd_parent_show(struct device *dev,
3693 struct device_attribute *attr,
3696 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3697 struct rbd_spec *spec = rbd_dev->parent_spec;
3702 return sprintf(buf, "(no parent image)\n");
3704 count = sprintf(bufp, "pool_id %llu\npool_name %s\n",
3705 (unsigned long long) spec->pool_id, spec->pool_name);
3710 count = sprintf(bufp, "image_id %s\nimage_name %s\n", spec->image_id,
3711 spec->image_name ? spec->image_name : "(unknown)");
3716 count = sprintf(bufp, "snap_id %llu\nsnap_name %s\n",
3717 (unsigned long long) spec->snap_id, spec->snap_name);
3722 count = sprintf(bufp, "overlap %llu\n", rbd_dev->parent_overlap);
3727 return (ssize_t) (bufp - buf);
3730 static ssize_t rbd_image_refresh(struct device *dev,
3731 struct device_attribute *attr,
3735 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3738 ret = rbd_dev_refresh(rbd_dev);
3740 rbd_warn(rbd_dev, ": manual header refresh error (%d)\n", ret);
3742 return ret < 0 ? ret : size;
3745 static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
3746 static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL);
3747 static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
3748 static DEVICE_ATTR(minor, S_IRUGO, rbd_minor_show, NULL);
3749 static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
3750 static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
3751 static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL);
3752 static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
3753 static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL);
3754 static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
3755 static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
3756 static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL);
3758 static struct attribute *rbd_attrs[] = {
3759 &dev_attr_size.attr,
3760 &dev_attr_features.attr,
3761 &dev_attr_major.attr,
3762 &dev_attr_minor.attr,
3763 &dev_attr_client_id.attr,
3764 &dev_attr_pool.attr,
3765 &dev_attr_pool_id.attr,
3766 &dev_attr_name.attr,
3767 &dev_attr_image_id.attr,
3768 &dev_attr_current_snap.attr,
3769 &dev_attr_parent.attr,
3770 &dev_attr_refresh.attr,
3774 static struct attribute_group rbd_attr_group = {
3778 static const struct attribute_group *rbd_attr_groups[] = {
3783 static void rbd_sysfs_dev_release(struct device *dev)
3787 static struct device_type rbd_device_type = {
3789 .groups = rbd_attr_groups,
3790 .release = rbd_sysfs_dev_release,
3793 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
3795 kref_get(&spec->kref);
3800 static void rbd_spec_free(struct kref *kref);
3801 static void rbd_spec_put(struct rbd_spec *spec)
3804 kref_put(&spec->kref, rbd_spec_free);
3807 static struct rbd_spec *rbd_spec_alloc(void)
3809 struct rbd_spec *spec;
3811 spec = kzalloc(sizeof (*spec), GFP_KERNEL);
3814 kref_init(&spec->kref);
3819 static void rbd_spec_free(struct kref *kref)
3821 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
3823 kfree(spec->pool_name);
3824 kfree(spec->image_id);
3825 kfree(spec->image_name);
3826 kfree(spec->snap_name);
3830 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
3831 struct rbd_spec *spec)
3833 struct rbd_device *rbd_dev;
3835 rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL);
3839 spin_lock_init(&rbd_dev->lock);
3841 atomic_set(&rbd_dev->parent_ref, 0);
3842 INIT_LIST_HEAD(&rbd_dev->node);
3843 init_rwsem(&rbd_dev->header_rwsem);
3845 rbd_dev->spec = spec;
3846 rbd_dev->rbd_client = rbdc;
3848 /* Initialize the layout used for all rbd requests */
3850 rbd_dev->layout.fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3851 rbd_dev->layout.fl_stripe_count = cpu_to_le32(1);
3852 rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3853 rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id);
3858 static void rbd_dev_destroy(struct rbd_device *rbd_dev)
3860 rbd_put_client(rbd_dev->rbd_client);
3861 rbd_spec_put(rbd_dev->spec);
3866 * Get the size and object order for an image snapshot, or if
3867 * snap_id is CEPH_NOSNAP, gets this information for the base
3870 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
3871 u8 *order, u64 *snap_size)
3873 __le64 snapid = cpu_to_le64(snap_id);
3878 } __attribute__ ((packed)) size_buf = { 0 };
3880 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3882 &snapid, sizeof (snapid),
3883 &size_buf, sizeof (size_buf));
3884 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3887 if (ret < sizeof (size_buf))
3891 *order = size_buf.order;
3892 dout(" order %u", (unsigned int)*order);
3894 *snap_size = le64_to_cpu(size_buf.size);
3896 dout(" snap_id 0x%016llx snap_size = %llu\n",
3897 (unsigned long long)snap_id,
3898 (unsigned long long)*snap_size);
3903 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
3905 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
3906 &rbd_dev->header.obj_order,
3907 &rbd_dev->header.image_size);
3910 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
3916 reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL);
3920 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3921 "rbd", "get_object_prefix", NULL, 0,
3922 reply_buf, RBD_OBJ_PREFIX_LEN_MAX);
3923 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3928 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
3929 p + ret, NULL, GFP_NOIO);
3932 if (IS_ERR(rbd_dev->header.object_prefix)) {
3933 ret = PTR_ERR(rbd_dev->header.object_prefix);
3934 rbd_dev->header.object_prefix = NULL;
3936 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix);
3944 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
3947 __le64 snapid = cpu_to_le64(snap_id);
3951 } __attribute__ ((packed)) features_buf = { 0 };
3955 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3956 "rbd", "get_features",
3957 &snapid, sizeof (snapid),
3958 &features_buf, sizeof (features_buf));
3959 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3962 if (ret < sizeof (features_buf))
3965 incompat = le64_to_cpu(features_buf.incompat);
3966 if (incompat & ~RBD_FEATURES_SUPPORTED)
3969 *snap_features = le64_to_cpu(features_buf.features);
3971 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
3972 (unsigned long long)snap_id,
3973 (unsigned long long)*snap_features,
3974 (unsigned long long)le64_to_cpu(features_buf.incompat));
3979 static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
3981 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
3982 &rbd_dev->header.features);
3985 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
3987 struct rbd_spec *parent_spec;
3989 void *reply_buf = NULL;
3999 parent_spec = rbd_spec_alloc();
4003 size = sizeof (__le64) + /* pool_id */
4004 sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */
4005 sizeof (__le64) + /* snap_id */
4006 sizeof (__le64); /* overlap */
4007 reply_buf = kmalloc(size, GFP_KERNEL);
4013 snapid = cpu_to_le64(CEPH_NOSNAP);
4014 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4015 "rbd", "get_parent",
4016 &snapid, sizeof (snapid),
4018 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4023 end = reply_buf + ret;
4025 ceph_decode_64_safe(&p, end, pool_id, out_err);
4026 if (pool_id == CEPH_NOPOOL) {
4028 * Either the parent never existed, or we have
4029 * record of it but the image got flattened so it no
4030 * longer has a parent. When the parent of a
4031 * layered image disappears we immediately set the
4032 * overlap to 0. The effect of this is that all new
4033 * requests will be treated as if the image had no
4036 if (rbd_dev->parent_overlap) {
4037 rbd_dev->parent_overlap = 0;
4039 rbd_dev_parent_put(rbd_dev);
4040 pr_info("%s: clone image has been flattened\n",
4041 rbd_dev->disk->disk_name);
4044 goto out; /* No parent? No problem. */
4047 /* The ceph file layout needs to fit pool id in 32 bits */
4050 if (pool_id > (u64)U32_MAX) {
4051 rbd_warn(NULL, "parent pool id too large (%llu > %u)\n",
4052 (unsigned long long)pool_id, U32_MAX);
4056 image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
4057 if (IS_ERR(image_id)) {
4058 ret = PTR_ERR(image_id);
4061 ceph_decode_64_safe(&p, end, snap_id, out_err);
4062 ceph_decode_64_safe(&p, end, overlap, out_err);
4065 * The parent won't change (except when the clone is
4066 * flattened, already handled that). So we only need to
4067 * record the parent spec we have not already done so.
4069 if (!rbd_dev->parent_spec) {
4070 parent_spec->pool_id = pool_id;
4071 parent_spec->image_id = image_id;
4072 parent_spec->snap_id = snap_id;
4073 rbd_dev->parent_spec = parent_spec;
4074 parent_spec = NULL; /* rbd_dev now owns this */
4080 * We always update the parent overlap. If it's zero we
4081 * treat it specially.
4083 rbd_dev->parent_overlap = overlap;
4087 /* A null parent_spec indicates it's the initial probe */
4091 * The overlap has become zero, so the clone
4092 * must have been resized down to 0 at some
4093 * point. Treat this the same as a flatten.
4095 rbd_dev_parent_put(rbd_dev);
4096 pr_info("%s: clone image now standalone\n",
4097 rbd_dev->disk->disk_name);
4100 * For the initial probe, if we find the
4101 * overlap is zero we just pretend there was
4104 rbd_warn(rbd_dev, "ignoring parent of "
4105 "clone with overlap 0\n");
4112 rbd_spec_put(parent_spec);
4117 static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
4121 __le64 stripe_count;
4122 } __attribute__ ((packed)) striping_info_buf = { 0 };
4123 size_t size = sizeof (striping_info_buf);
4130 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4131 "rbd", "get_stripe_unit_count", NULL, 0,
4132 (char *)&striping_info_buf, size);
4133 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4140 * We don't actually support the "fancy striping" feature
4141 * (STRIPINGV2) yet, but if the striping sizes are the
4142 * defaults the behavior is the same as before. So find
4143 * out, and only fail if the image has non-default values.
4146 obj_size = (u64)1 << rbd_dev->header.obj_order;
4147 p = &striping_info_buf;
4148 stripe_unit = ceph_decode_64(&p);
4149 if (stripe_unit != obj_size) {
4150 rbd_warn(rbd_dev, "unsupported stripe unit "
4151 "(got %llu want %llu)",
4152 stripe_unit, obj_size);
4155 stripe_count = ceph_decode_64(&p);
4156 if (stripe_count != 1) {
4157 rbd_warn(rbd_dev, "unsupported stripe count "
4158 "(got %llu want 1)", stripe_count);
4161 rbd_dev->header.stripe_unit = stripe_unit;
4162 rbd_dev->header.stripe_count = stripe_count;
4167 static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
4169 size_t image_id_size;
4174 void *reply_buf = NULL;
4176 char *image_name = NULL;
4179 rbd_assert(!rbd_dev->spec->image_name);
4181 len = strlen(rbd_dev->spec->image_id);
4182 image_id_size = sizeof (__le32) + len;
4183 image_id = kmalloc(image_id_size, GFP_KERNEL);
4188 end = image_id + image_id_size;
4189 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
4191 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
4192 reply_buf = kmalloc(size, GFP_KERNEL);
4196 ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY,
4197 "rbd", "dir_get_name",
4198 image_id, image_id_size,
4203 end = reply_buf + ret;
4205 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
4206 if (IS_ERR(image_name))
4209 dout("%s: name is %s len is %zd\n", __func__, image_name, len);
4217 static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4219 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
4220 const char *snap_name;
4223 /* Skip over names until we find the one we are looking for */
4225 snap_name = rbd_dev->header.snap_names;
4226 while (which < snapc->num_snaps) {
4227 if (!strcmp(name, snap_name))
4228 return snapc->snaps[which];
4229 snap_name += strlen(snap_name) + 1;
4235 static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4237 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
4242 for (which = 0; !found && which < snapc->num_snaps; which++) {
4243 const char *snap_name;
4245 snap_id = snapc->snaps[which];
4246 snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
4247 if (IS_ERR(snap_name)) {
4248 /* ignore no-longer existing snapshots */
4249 if (PTR_ERR(snap_name) == -ENOENT)
4254 found = !strcmp(name, snap_name);
4257 return found ? snap_id : CEPH_NOSNAP;
4261 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
4262 * no snapshot by that name is found, or if an error occurs.
4264 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4266 if (rbd_dev->image_format == 1)
4267 return rbd_v1_snap_id_by_name(rbd_dev, name);
4269 return rbd_v2_snap_id_by_name(rbd_dev, name);
4273 * When an rbd image has a parent image, it is identified by the
4274 * pool, image, and snapshot ids (not names). This function fills
4275 * in the names for those ids. (It's OK if we can't figure out the
4276 * name for an image id, but the pool and snapshot ids should always
4277 * exist and have names.) All names in an rbd spec are dynamically
4280 * When an image being mapped (not a parent) is probed, we have the
4281 * pool name and pool id, image name and image id, and the snapshot
4282 * name. The only thing we're missing is the snapshot id.
4284 static int rbd_dev_spec_update(struct rbd_device *rbd_dev)
4286 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4287 struct rbd_spec *spec = rbd_dev->spec;
4288 const char *pool_name;
4289 const char *image_name;
4290 const char *snap_name;
4294 * An image being mapped will have the pool name (etc.), but
4295 * we need to look up the snapshot id.
4297 if (spec->pool_name) {
4298 if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
4301 snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
4302 if (snap_id == CEPH_NOSNAP)
4304 spec->snap_id = snap_id;
4306 spec->snap_id = CEPH_NOSNAP;
4312 /* Get the pool name; we have to make our own copy of this */
4314 pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
4316 rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
4319 pool_name = kstrdup(pool_name, GFP_KERNEL);
4323 /* Fetch the image name; tolerate failure here */
4325 image_name = rbd_dev_image_name(rbd_dev);
4327 rbd_warn(rbd_dev, "unable to get image name");
4329 /* Look up the snapshot name, and make a copy */
4331 snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
4332 if (IS_ERR(snap_name)) {
4333 ret = PTR_ERR(snap_name);
4337 spec->pool_name = pool_name;
4338 spec->image_name = image_name;
4339 spec->snap_name = snap_name;
4349 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
4358 struct ceph_snap_context *snapc;
4362 * We'll need room for the seq value (maximum snapshot id),
4363 * snapshot count, and array of that many snapshot ids.
4364 * For now we have a fixed upper limit on the number we're
4365 * prepared to receive.
4367 size = sizeof (__le64) + sizeof (__le32) +
4368 RBD_MAX_SNAP_COUNT * sizeof (__le64);
4369 reply_buf = kzalloc(size, GFP_KERNEL);
4373 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4374 "rbd", "get_snapcontext", NULL, 0,
4376 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4381 end = reply_buf + ret;
4383 ceph_decode_64_safe(&p, end, seq, out);
4384 ceph_decode_32_safe(&p, end, snap_count, out);
4387 * Make sure the reported number of snapshot ids wouldn't go
4388 * beyond the end of our buffer. But before checking that,
4389 * make sure the computed size of the snapshot context we
4390 * allocate is representable in a size_t.
4392 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
4397 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
4401 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
4407 for (i = 0; i < snap_count; i++)
4408 snapc->snaps[i] = ceph_decode_64(&p);
4410 ceph_put_snap_context(rbd_dev->header.snapc);
4411 rbd_dev->header.snapc = snapc;
4413 dout(" snap context seq = %llu, snap_count = %u\n",
4414 (unsigned long long)seq, (unsigned int)snap_count);
4421 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
4432 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
4433 reply_buf = kmalloc(size, GFP_KERNEL);
4435 return ERR_PTR(-ENOMEM);
4437 snapid = cpu_to_le64(snap_id);
4438 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4439 "rbd", "get_snapshot_name",
4440 &snapid, sizeof (snapid),
4442 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4444 snap_name = ERR_PTR(ret);
4449 end = reply_buf + ret;
4450 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
4451 if (IS_ERR(snap_name))
4454 dout(" snap_id 0x%016llx snap_name = %s\n",
4455 (unsigned long long)snap_id, snap_name);
4462 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
4464 bool first_time = rbd_dev->header.object_prefix == NULL;
4467 ret = rbd_dev_v2_image_size(rbd_dev);
4472 ret = rbd_dev_v2_header_onetime(rbd_dev);
4478 * If the image supports layering, get the parent info. We
4479 * need to probe the first time regardless. Thereafter we
4480 * only need to if there's a parent, to see if it has
4481 * disappeared due to the mapped image getting flattened.
4483 if (rbd_dev->header.features & RBD_FEATURE_LAYERING &&
4484 (first_time || rbd_dev->parent_spec)) {
4487 ret = rbd_dev_v2_parent_info(rbd_dev);
4492 * Print a warning if this is the initial probe and
4493 * the image has a parent. Don't print it if the
4494 * image now being probed is itself a parent. We
4495 * can tell at this point because we won't know its
4496 * pool name yet (just its pool id).
4498 warn = rbd_dev->parent_spec && rbd_dev->spec->pool_name;
4499 if (first_time && warn)
4500 rbd_warn(rbd_dev, "WARNING: kernel layering "
4501 "is EXPERIMENTAL!");
4504 if (rbd_dev->spec->snap_id == CEPH_NOSNAP)
4505 if (rbd_dev->mapping.size != rbd_dev->header.image_size)
4506 rbd_dev->mapping.size = rbd_dev->header.image_size;
4508 ret = rbd_dev_v2_snap_context(rbd_dev);
4509 dout("rbd_dev_v2_snap_context returned %d\n", ret);
4514 static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
4519 dev = &rbd_dev->dev;
4520 dev->bus = &rbd_bus_type;
4521 dev->type = &rbd_device_type;
4522 dev->parent = &rbd_root_dev;
4523 dev->release = rbd_dev_device_release;
4524 dev_set_name(dev, "%d", rbd_dev->dev_id);
4525 ret = device_register(dev);
4530 static void rbd_bus_del_dev(struct rbd_device *rbd_dev)
4532 device_unregister(&rbd_dev->dev);
4536 * Get a unique rbd identifier for the given new rbd_dev, and add
4537 * the rbd_dev to the global list.
4539 static int rbd_dev_id_get(struct rbd_device *rbd_dev)
4543 new_dev_id = ida_simple_get(&rbd_dev_id_ida,
4544 0, minor_to_rbd_dev_id(1 << MINORBITS),
4549 rbd_dev->dev_id = new_dev_id;
4551 spin_lock(&rbd_dev_list_lock);
4552 list_add_tail(&rbd_dev->node, &rbd_dev_list);
4553 spin_unlock(&rbd_dev_list_lock);
4555 dout("rbd_dev %p given dev id %d\n", rbd_dev, rbd_dev->dev_id);
4561 * Remove an rbd_dev from the global list, and record that its
4562 * identifier is no longer in use.
4564 static void rbd_dev_id_put(struct rbd_device *rbd_dev)
4566 spin_lock(&rbd_dev_list_lock);
4567 list_del_init(&rbd_dev->node);
4568 spin_unlock(&rbd_dev_list_lock);
4570 ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id);
4572 dout("rbd_dev %p released dev id %d\n", rbd_dev, rbd_dev->dev_id);
4576 * Skips over white space at *buf, and updates *buf to point to the
4577 * first found non-space character (if any). Returns the length of
4578 * the token (string of non-white space characters) found. Note
4579 * that *buf must be terminated with '\0'.
4581 static inline size_t next_token(const char **buf)
4584 * These are the characters that produce nonzero for
4585 * isspace() in the "C" and "POSIX" locales.
4587 const char *spaces = " \f\n\r\t\v";
4589 *buf += strspn(*buf, spaces); /* Find start of token */
4591 return strcspn(*buf, spaces); /* Return token length */
4595 * Finds the next token in *buf, and if the provided token buffer is
4596 * big enough, copies the found token into it. The result, if
4597 * copied, is guaranteed to be terminated with '\0'. Note that *buf
4598 * must be terminated with '\0' on entry.
4600 * Returns the length of the token found (not including the '\0').
4601 * Return value will be 0 if no token is found, and it will be >=
4602 * token_size if the token would not fit.
4604 * The *buf pointer will be updated to point beyond the end of the
4605 * found token. Note that this occurs even if the token buffer is
4606 * too small to hold it.
4608 static inline size_t copy_token(const char **buf,
4614 len = next_token(buf);
4615 if (len < token_size) {
4616 memcpy(token, *buf, len);
4617 *(token + len) = '\0';
4625 * Finds the next token in *buf, dynamically allocates a buffer big
4626 * enough to hold a copy of it, and copies the token into the new
4627 * buffer. The copy is guaranteed to be terminated with '\0'. Note
4628 * that a duplicate buffer is created even for a zero-length token.
4630 * Returns a pointer to the newly-allocated duplicate, or a null
4631 * pointer if memory for the duplicate was not available. If
4632 * the lenp argument is a non-null pointer, the length of the token
4633 * (not including the '\0') is returned in *lenp.
4635 * If successful, the *buf pointer will be updated to point beyond
4636 * the end of the found token.
4638 * Note: uses GFP_KERNEL for allocation.
4640 static inline char *dup_token(const char **buf, size_t *lenp)
4645 len = next_token(buf);
4646 dup = kmemdup(*buf, len + 1, GFP_KERNEL);
4649 *(dup + len) = '\0';
4659 * Parse the options provided for an "rbd add" (i.e., rbd image
4660 * mapping) request. These arrive via a write to /sys/bus/rbd/add,
4661 * and the data written is passed here via a NUL-terminated buffer.
4662 * Returns 0 if successful or an error code otherwise.
4664 * The information extracted from these options is recorded in
4665 * the other parameters which return dynamically-allocated
4668 * The address of a pointer that will refer to a ceph options
4669 * structure. Caller must release the returned pointer using
4670 * ceph_destroy_options() when it is no longer needed.
4672 * Address of an rbd options pointer. Fully initialized by
4673 * this function; caller must release with kfree().
4675 * Address of an rbd image specification pointer. Fully
4676 * initialized by this function based on parsed options.
4677 * Caller must release with rbd_spec_put().
4679 * The options passed take this form:
4680 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
4683 * A comma-separated list of one or more monitor addresses.
4684 * A monitor address is an ip address, optionally followed
4685 * by a port number (separated by a colon).
4686 * I.e.: ip1[:port1][,ip2[:port2]...]
4688 * A comma-separated list of ceph and/or rbd options.
4690 * The name of the rados pool containing the rbd image.
4692 * The name of the image in that pool to map.
4694 * An optional snapshot id. If provided, the mapping will
4695 * present data from the image at the time that snapshot was
4696 * created. The image head is used if no snapshot id is
4697 * provided. Snapshot mappings are always read-only.
4699 static int rbd_add_parse_args(const char *buf,
4700 struct ceph_options **ceph_opts,
4701 struct rbd_options **opts,
4702 struct rbd_spec **rbd_spec)
4706 const char *mon_addrs;
4708 size_t mon_addrs_size;
4709 struct rbd_spec *spec = NULL;
4710 struct rbd_options *rbd_opts = NULL;
4711 struct ceph_options *copts;
4714 /* The first four tokens are required */
4716 len = next_token(&buf);
4718 rbd_warn(NULL, "no monitor address(es) provided");
4722 mon_addrs_size = len + 1;
4726 options = dup_token(&buf, NULL);
4730 rbd_warn(NULL, "no options provided");
4734 spec = rbd_spec_alloc();
4738 spec->pool_name = dup_token(&buf, NULL);
4739 if (!spec->pool_name)
4741 if (!*spec->pool_name) {
4742 rbd_warn(NULL, "no pool name provided");
4746 spec->image_name = dup_token(&buf, NULL);
4747 if (!spec->image_name)
4749 if (!*spec->image_name) {
4750 rbd_warn(NULL, "no image name provided");
4755 * Snapshot name is optional; default is to use "-"
4756 * (indicating the head/no snapshot).
4758 len = next_token(&buf);
4760 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
4761 len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
4762 } else if (len > RBD_MAX_SNAP_NAME_LEN) {
4763 ret = -ENAMETOOLONG;
4766 snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
4769 *(snap_name + len) = '\0';
4770 spec->snap_name = snap_name;
4772 /* Initialize all rbd options to the defaults */
4774 rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL);
4778 rbd_opts->read_only = RBD_READ_ONLY_DEFAULT;
4780 copts = ceph_parse_options(options, mon_addrs,
4781 mon_addrs + mon_addrs_size - 1,
4782 parse_rbd_opts_token, rbd_opts);
4783 if (IS_ERR(copts)) {
4784 ret = PTR_ERR(copts);
4805 * Return pool id (>= 0) or a negative error code.
4807 static int rbd_add_get_pool_id(struct rbd_client *rbdc, const char *pool_name)
4810 unsigned long timeout = rbdc->client->options->mount_timeout * HZ;
4815 ret = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, pool_name);
4816 if (ret == -ENOENT && tries++ < 1) {
4817 ret = ceph_monc_do_get_version(&rbdc->client->monc, "osdmap",
4822 if (rbdc->client->osdc.osdmap->epoch < newest_epoch) {
4823 ceph_monc_request_next_osdmap(&rbdc->client->monc);
4824 (void) ceph_monc_wait_osdmap(&rbdc->client->monc,
4825 newest_epoch, timeout);
4828 /* the osdmap we have is new enough */
4837 * An rbd format 2 image has a unique identifier, distinct from the
4838 * name given to it by the user. Internally, that identifier is
4839 * what's used to specify the names of objects related to the image.
4841 * A special "rbd id" object is used to map an rbd image name to its
4842 * id. If that object doesn't exist, then there is no v2 rbd image
4843 * with the supplied name.
4845 * This function will record the given rbd_dev's image_id field if
4846 * it can be determined, and in that case will return 0. If any
4847 * errors occur a negative errno will be returned and the rbd_dev's
4848 * image_id field will be unchanged (and should be NULL).
4850 static int rbd_dev_image_id(struct rbd_device *rbd_dev)
4859 * When probing a parent image, the image id is already
4860 * known (and the image name likely is not). There's no
4861 * need to fetch the image id again in this case. We
4862 * do still need to set the image format though.
4864 if (rbd_dev->spec->image_id) {
4865 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;
4871 * First, see if the format 2 image id file exists, and if
4872 * so, get the image's persistent id from it.
4874 size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name);
4875 object_name = kmalloc(size, GFP_NOIO);
4878 sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name);
4879 dout("rbd id object name is %s\n", object_name);
4881 /* Response will be an encoded string, which includes a length */
4883 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
4884 response = kzalloc(size, GFP_NOIO);
4890 /* If it doesn't exist we'll assume it's a format 1 image */
4892 ret = rbd_obj_method_sync(rbd_dev, object_name,
4893 "rbd", "get_id", NULL, 0,
4894 response, RBD_IMAGE_ID_LEN_MAX);
4895 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4896 if (ret == -ENOENT) {
4897 image_id = kstrdup("", GFP_KERNEL);
4898 ret = image_id ? 0 : -ENOMEM;
4900 rbd_dev->image_format = 1;
4901 } else if (ret > sizeof (__le32)) {
4904 image_id = ceph_extract_encoded_string(&p, p + ret,
4906 ret = PTR_ERR_OR_ZERO(image_id);
4908 rbd_dev->image_format = 2;
4914 rbd_dev->spec->image_id = image_id;
4915 dout("image_id is %s\n", image_id);
4925 * Undo whatever state changes are made by v1 or v2 header info
4928 static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
4930 struct rbd_image_header *header;
4932 /* Drop parent reference unless it's already been done (or none) */
4934 if (rbd_dev->parent_overlap)
4935 rbd_dev_parent_put(rbd_dev);
4937 /* Free dynamic fields from the header, then zero it out */
4939 header = &rbd_dev->header;
4940 ceph_put_snap_context(header->snapc);
4941 kfree(header->snap_sizes);
4942 kfree(header->snap_names);
4943 kfree(header->object_prefix);
4944 memset(header, 0, sizeof (*header));
4947 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev)
4951 ret = rbd_dev_v2_object_prefix(rbd_dev);
4956 * Get the and check features for the image. Currently the
4957 * features are assumed to never change.
4959 ret = rbd_dev_v2_features(rbd_dev);
4963 /* If the image supports fancy striping, get its parameters */
4965 if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
4966 ret = rbd_dev_v2_striping_info(rbd_dev);
4970 /* No support for crypto and compression type format 2 images */
4974 rbd_dev->header.features = 0;
4975 kfree(rbd_dev->header.object_prefix);
4976 rbd_dev->header.object_prefix = NULL;
4981 static int rbd_dev_probe_parent(struct rbd_device *rbd_dev)
4983 struct rbd_device *parent = NULL;
4984 struct rbd_spec *parent_spec;
4985 struct rbd_client *rbdc;
4988 if (!rbd_dev->parent_spec)
4991 * We need to pass a reference to the client and the parent
4992 * spec when creating the parent rbd_dev. Images related by
4993 * parent/child relationships always share both.
4995 parent_spec = rbd_spec_get(rbd_dev->parent_spec);
4996 rbdc = __rbd_get_client(rbd_dev->rbd_client);
4999 parent = rbd_dev_create(rbdc, parent_spec);
5003 ret = rbd_dev_image_probe(parent, false);
5006 rbd_dev->parent = parent;
5007 atomic_set(&rbd_dev->parent_ref, 1);
5012 rbd_dev_unparent(rbd_dev);
5013 kfree(rbd_dev->header_name);
5014 rbd_dev_destroy(parent);
5016 rbd_put_client(rbdc);
5017 rbd_spec_put(parent_spec);
5023 static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
5027 /* Get an id and fill in device name. */
5029 ret = rbd_dev_id_get(rbd_dev);
5033 BUILD_BUG_ON(DEV_NAME_LEN
5034 < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
5035 sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id);
5037 /* Record our major and minor device numbers. */
5039 if (!single_major) {
5040 ret = register_blkdev(0, rbd_dev->name);
5044 rbd_dev->major = ret;
5047 rbd_dev->major = rbd_major;
5048 rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id);
5051 /* Set up the blkdev mapping. */
5053 ret = rbd_init_disk(rbd_dev);
5055 goto err_out_blkdev;
5057 ret = rbd_dev_mapping_set(rbd_dev);
5060 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
5061 set_disk_ro(rbd_dev->disk, rbd_dev->mapping.read_only);
5063 ret = rbd_bus_add_dev(rbd_dev);
5065 goto err_out_mapping;
5067 /* Everything's ready. Announce the disk to the world. */
5069 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
5070 add_disk(rbd_dev->disk);
5072 pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name,
5073 (unsigned long long) rbd_dev->mapping.size);
5078 rbd_dev_mapping_clear(rbd_dev);
5080 rbd_free_disk(rbd_dev);
5083 unregister_blkdev(rbd_dev->major, rbd_dev->name);
5085 rbd_dev_id_put(rbd_dev);
5086 rbd_dev_mapping_clear(rbd_dev);
5091 static int rbd_dev_header_name(struct rbd_device *rbd_dev)
5093 struct rbd_spec *spec = rbd_dev->spec;
5096 /* Record the header object name for this rbd image. */
5098 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
5100 if (rbd_dev->image_format == 1)
5101 size = strlen(spec->image_name) + sizeof (RBD_SUFFIX);
5103 size = sizeof (RBD_HEADER_PREFIX) + strlen(spec->image_id);
5105 rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
5106 if (!rbd_dev->header_name)
5109 if (rbd_dev->image_format == 1)
5110 sprintf(rbd_dev->header_name, "%s%s",
5111 spec->image_name, RBD_SUFFIX);
5113 sprintf(rbd_dev->header_name, "%s%s",
5114 RBD_HEADER_PREFIX, spec->image_id);
5118 static void rbd_dev_image_release(struct rbd_device *rbd_dev)
5120 rbd_dev_unprobe(rbd_dev);
5121 kfree(rbd_dev->header_name);
5122 rbd_dev->header_name = NULL;
5123 rbd_dev->image_format = 0;
5124 kfree(rbd_dev->spec->image_id);
5125 rbd_dev->spec->image_id = NULL;
5127 rbd_dev_destroy(rbd_dev);
5131 * Probe for the existence of the header object for the given rbd
5132 * device. If this image is the one being mapped (i.e., not a
5133 * parent), initiate a watch on its header object before using that
5134 * object to get detailed information about the rbd image.
5136 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping)
5141 * Get the id from the image id object. Unless there's an
5142 * error, rbd_dev->spec->image_id will be filled in with
5143 * a dynamically-allocated string, and rbd_dev->image_format
5144 * will be set to either 1 or 2.
5146 ret = rbd_dev_image_id(rbd_dev);
5149 rbd_assert(rbd_dev->spec->image_id);
5150 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
5152 ret = rbd_dev_header_name(rbd_dev);
5154 goto err_out_format;
5157 ret = rbd_dev_header_watch_sync(rbd_dev);
5159 goto out_header_name;
5162 if (rbd_dev->image_format == 1)
5163 ret = rbd_dev_v1_header_info(rbd_dev);
5165 ret = rbd_dev_v2_header_info(rbd_dev);
5169 ret = rbd_dev_spec_update(rbd_dev);
5173 ret = rbd_dev_probe_parent(rbd_dev);
5177 dout("discovered format %u image, header name is %s\n",
5178 rbd_dev->image_format, rbd_dev->header_name);
5182 rbd_dev_unprobe(rbd_dev);
5185 rbd_dev_header_unwatch_sync(rbd_dev);
5187 kfree(rbd_dev->header_name);
5188 rbd_dev->header_name = NULL;
5190 rbd_dev->image_format = 0;
5191 kfree(rbd_dev->spec->image_id);
5192 rbd_dev->spec->image_id = NULL;
5194 dout("probe failed, returning %d\n", ret);
5199 static ssize_t do_rbd_add(struct bus_type *bus,
5203 struct rbd_device *rbd_dev = NULL;
5204 struct ceph_options *ceph_opts = NULL;
5205 struct rbd_options *rbd_opts = NULL;
5206 struct rbd_spec *spec = NULL;
5207 struct rbd_client *rbdc;
5211 if (!try_module_get(THIS_MODULE))
5214 /* parse add command */
5215 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
5217 goto err_out_module;
5218 read_only = rbd_opts->read_only;
5220 rbd_opts = NULL; /* done with this */
5222 rbdc = rbd_get_client(ceph_opts);
5229 rc = rbd_add_get_pool_id(rbdc, spec->pool_name);
5231 goto err_out_client;
5232 spec->pool_id = (u64)rc;
5234 /* The ceph file layout needs to fit pool id in 32 bits */
5236 if (spec->pool_id > (u64)U32_MAX) {
5237 rbd_warn(NULL, "pool id too large (%llu > %u)\n",
5238 (unsigned long long)spec->pool_id, U32_MAX);
5240 goto err_out_client;
5243 rbd_dev = rbd_dev_create(rbdc, spec);
5245 goto err_out_client;
5246 rbdc = NULL; /* rbd_dev now owns this */
5247 spec = NULL; /* rbd_dev now owns this */
5249 rc = rbd_dev_image_probe(rbd_dev, true);
5251 goto err_out_rbd_dev;
5253 /* If we are mapping a snapshot it must be marked read-only */
5255 if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
5257 rbd_dev->mapping.read_only = read_only;
5259 rc = rbd_dev_device_setup(rbd_dev);
5262 * rbd_dev_header_unwatch_sync() can't be moved into
5263 * rbd_dev_image_release() without refactoring, see
5264 * commit 1f3ef78861ac.
5266 rbd_dev_header_unwatch_sync(rbd_dev);
5267 rbd_dev_image_release(rbd_dev);
5268 goto err_out_module;
5274 rbd_dev_destroy(rbd_dev);
5276 rbd_put_client(rbdc);
5280 module_put(THIS_MODULE);
5282 dout("Error adding device %s\n", buf);
5287 static ssize_t rbd_add(struct bus_type *bus,
5294 return do_rbd_add(bus, buf, count);
5297 static ssize_t rbd_add_single_major(struct bus_type *bus,
5301 return do_rbd_add(bus, buf, count);
5304 static void rbd_dev_device_release(struct device *dev)
5306 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5308 rbd_free_disk(rbd_dev);
5309 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
5310 rbd_dev_mapping_clear(rbd_dev);
5312 unregister_blkdev(rbd_dev->major, rbd_dev->name);
5313 rbd_dev_id_put(rbd_dev);
5314 rbd_dev_mapping_clear(rbd_dev);
5317 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
5319 while (rbd_dev->parent) {
5320 struct rbd_device *first = rbd_dev;
5321 struct rbd_device *second = first->parent;
5322 struct rbd_device *third;
5325 * Follow to the parent with no grandparent and
5328 while (second && (third = second->parent)) {
5333 rbd_dev_image_release(second);
5334 first->parent = NULL;
5335 first->parent_overlap = 0;
5337 rbd_assert(first->parent_spec);
5338 rbd_spec_put(first->parent_spec);
5339 first->parent_spec = NULL;
5343 static ssize_t do_rbd_remove(struct bus_type *bus,
5347 struct rbd_device *rbd_dev = NULL;
5348 struct list_head *tmp;
5351 bool already = false;
5354 ret = kstrtoul(buf, 10, &ul);
5358 /* convert to int; abort if we lost anything in the conversion */
5364 spin_lock(&rbd_dev_list_lock);
5365 list_for_each(tmp, &rbd_dev_list) {
5366 rbd_dev = list_entry(tmp, struct rbd_device, node);
5367 if (rbd_dev->dev_id == dev_id) {
5373 spin_lock_irq(&rbd_dev->lock);
5374 if (rbd_dev->open_count)
5377 already = test_and_set_bit(RBD_DEV_FLAG_REMOVING,
5379 spin_unlock_irq(&rbd_dev->lock);
5381 spin_unlock(&rbd_dev_list_lock);
5382 if (ret < 0 || already)
5385 rbd_dev_header_unwatch_sync(rbd_dev);
5387 * flush remaining watch callbacks - these must be complete
5388 * before the osd_client is shutdown
5390 dout("%s: flushing notifies", __func__);
5391 ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc);
5394 * Don't free anything from rbd_dev->disk until after all
5395 * notifies are completely processed. Otherwise
5396 * rbd_bus_del_dev() will race with rbd_watch_cb(), resulting
5397 * in a potential use after free of rbd_dev->disk or rbd_dev.
5399 rbd_bus_del_dev(rbd_dev);
5400 rbd_dev_image_release(rbd_dev);
5401 module_put(THIS_MODULE);
5406 static ssize_t rbd_remove(struct bus_type *bus,
5413 return do_rbd_remove(bus, buf, count);
5416 static ssize_t rbd_remove_single_major(struct bus_type *bus,
5420 return do_rbd_remove(bus, buf, count);
5424 * create control files in sysfs
5427 static int rbd_sysfs_init(void)
5431 ret = device_register(&rbd_root_dev);
5435 ret = bus_register(&rbd_bus_type);
5437 device_unregister(&rbd_root_dev);
5442 static void rbd_sysfs_cleanup(void)
5444 bus_unregister(&rbd_bus_type);
5445 device_unregister(&rbd_root_dev);
5448 static int rbd_slab_init(void)
5450 rbd_assert(!rbd_img_request_cache);
5451 rbd_img_request_cache = kmem_cache_create("rbd_img_request",
5452 sizeof (struct rbd_img_request),
5453 __alignof__(struct rbd_img_request),
5455 if (!rbd_img_request_cache)
5458 rbd_assert(!rbd_obj_request_cache);
5459 rbd_obj_request_cache = kmem_cache_create("rbd_obj_request",
5460 sizeof (struct rbd_obj_request),
5461 __alignof__(struct rbd_obj_request),
5463 if (!rbd_obj_request_cache)
5466 rbd_assert(!rbd_segment_name_cache);
5467 rbd_segment_name_cache = kmem_cache_create("rbd_segment_name",
5468 CEPH_MAX_OID_NAME_LEN + 1, 1, 0, NULL);
5469 if (rbd_segment_name_cache)
5472 if (rbd_obj_request_cache) {
5473 kmem_cache_destroy(rbd_obj_request_cache);
5474 rbd_obj_request_cache = NULL;
5477 kmem_cache_destroy(rbd_img_request_cache);
5478 rbd_img_request_cache = NULL;
5483 static void rbd_slab_exit(void)
5485 rbd_assert(rbd_segment_name_cache);
5486 kmem_cache_destroy(rbd_segment_name_cache);
5487 rbd_segment_name_cache = NULL;
5489 rbd_assert(rbd_obj_request_cache);
5490 kmem_cache_destroy(rbd_obj_request_cache);
5491 rbd_obj_request_cache = NULL;
5493 rbd_assert(rbd_img_request_cache);
5494 kmem_cache_destroy(rbd_img_request_cache);
5495 rbd_img_request_cache = NULL;
5498 static int __init rbd_init(void)
5502 if (!libceph_compatible(NULL)) {
5503 rbd_warn(NULL, "libceph incompatibility (quitting)");
5507 rc = rbd_slab_init();
5512 rbd_major = register_blkdev(0, RBD_DRV_NAME);
5513 if (rbd_major < 0) {
5519 rc = rbd_sysfs_init();
5521 goto err_out_blkdev;
5524 pr_info("loaded (major %d)\n", rbd_major);
5526 pr_info("loaded\n");
5532 unregister_blkdev(rbd_major, RBD_DRV_NAME);
5538 static void __exit rbd_exit(void)
5540 ida_destroy(&rbd_dev_id_ida);
5541 rbd_sysfs_cleanup();
5543 unregister_blkdev(rbd_major, RBD_DRV_NAME);
5547 module_init(rbd_init);
5548 module_exit(rbd_exit);
5550 MODULE_AUTHOR("Alex Elder <elder@inktank.com>");
5551 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
5552 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
5553 /* following authorship retained from original osdblk.c */
5554 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
5556 MODULE_DESCRIPTION("RADOS Block Device (RBD) driver");
5557 MODULE_LICENSE("GPL");