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_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);
2968 * Until adequate refresh error handling is in place, there is
2969 * not much we can do here, except warn.
2971 * See http://tracker.ceph.com/issues/5040
2973 ret = rbd_dev_refresh(rbd_dev);
2975 rbd_warn(rbd_dev, "refresh failed: %d\n", ret);
2977 ret = rbd_obj_notify_ack_sync(rbd_dev, notify_id);
2979 rbd_warn(rbd_dev, "notify_ack ret %d\n", ret);
2983 * Send a (un)watch request and wait for the ack. Return a request
2984 * with a ref held on success or error.
2986 static struct rbd_obj_request *rbd_obj_watch_request_helper(
2987 struct rbd_device *rbd_dev,
2990 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
2991 struct rbd_obj_request *obj_request;
2994 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
2995 OBJ_REQUEST_NODATA);
2997 return ERR_PTR(-ENOMEM);
2999 obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, 1,
3001 if (!obj_request->osd_req) {
3006 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
3007 rbd_dev->watch_event->cookie, 0, watch);
3008 rbd_osd_req_format_write(obj_request);
3011 ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
3013 ret = rbd_obj_request_submit(osdc, obj_request);
3017 ret = rbd_obj_request_wait(obj_request);
3021 ret = obj_request->result;
3024 rbd_obj_request_end(obj_request);
3031 rbd_obj_request_put(obj_request);
3032 return ERR_PTR(ret);
3036 * Initiate a watch request, synchronously.
3038 static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev)
3040 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3041 struct rbd_obj_request *obj_request;
3044 rbd_assert(!rbd_dev->watch_event);
3045 rbd_assert(!rbd_dev->watch_request);
3047 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
3048 &rbd_dev->watch_event);
3052 obj_request = rbd_obj_watch_request_helper(rbd_dev, true);
3053 if (IS_ERR(obj_request)) {
3054 ceph_osdc_cancel_event(rbd_dev->watch_event);
3055 rbd_dev->watch_event = NULL;
3056 return PTR_ERR(obj_request);
3060 * A watch request is set to linger, so the underlying osd
3061 * request won't go away until we unregister it. We retain
3062 * a pointer to the object request during that time (in
3063 * rbd_dev->watch_request), so we'll keep a reference to it.
3064 * We'll drop that reference after we've unregistered it in
3065 * rbd_dev_header_unwatch_sync().
3067 rbd_dev->watch_request = obj_request;
3073 * Tear down a watch request, synchronously.
3075 static void rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev)
3077 struct rbd_obj_request *obj_request;
3079 rbd_assert(rbd_dev->watch_event);
3080 rbd_assert(rbd_dev->watch_request);
3082 rbd_obj_request_end(rbd_dev->watch_request);
3083 rbd_obj_request_put(rbd_dev->watch_request);
3084 rbd_dev->watch_request = NULL;
3086 obj_request = rbd_obj_watch_request_helper(rbd_dev, false);
3087 if (!IS_ERR(obj_request))
3088 rbd_obj_request_put(obj_request);
3090 rbd_warn(rbd_dev, "unable to tear down watch request (%ld)",
3091 PTR_ERR(obj_request));
3093 ceph_osdc_cancel_event(rbd_dev->watch_event);
3094 rbd_dev->watch_event = NULL;
3098 * Synchronous osd object method call. Returns the number of bytes
3099 * returned in the outbound buffer, or a negative error code.
3101 static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
3102 const char *object_name,
3103 const char *class_name,
3104 const char *method_name,
3105 const void *outbound,
3106 size_t outbound_size,
3108 size_t inbound_size)
3110 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3111 struct rbd_obj_request *obj_request;
3112 struct page **pages;
3117 * Method calls are ultimately read operations. The result
3118 * should placed into the inbound buffer provided. They
3119 * also supply outbound data--parameters for the object
3120 * method. Currently if this is present it will be a
3123 page_count = (u32)calc_pages_for(0, inbound_size);
3124 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
3126 return PTR_ERR(pages);
3129 obj_request = rbd_obj_request_create(object_name, 0, inbound_size,
3134 obj_request->pages = pages;
3135 obj_request->page_count = page_count;
3137 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1,
3139 if (!obj_request->osd_req)
3142 osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL,
3143 class_name, method_name);
3144 if (outbound_size) {
3145 struct ceph_pagelist *pagelist;
3147 pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS);
3151 ceph_pagelist_init(pagelist);
3152 ceph_pagelist_append(pagelist, outbound, outbound_size);
3153 osd_req_op_cls_request_data_pagelist(obj_request->osd_req, 0,
3156 osd_req_op_cls_response_data_pages(obj_request->osd_req, 0,
3157 obj_request->pages, inbound_size,
3159 rbd_osd_req_format_read(obj_request);
3161 ret = rbd_obj_request_submit(osdc, obj_request);
3164 ret = rbd_obj_request_wait(obj_request);
3168 ret = obj_request->result;
3172 rbd_assert(obj_request->xferred < (u64)INT_MAX);
3173 ret = (int)obj_request->xferred;
3174 ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred);
3177 rbd_obj_request_put(obj_request);
3179 ceph_release_page_vector(pages, page_count);
3184 static void rbd_request_fn(struct request_queue *q)
3185 __releases(q->queue_lock) __acquires(q->queue_lock)
3187 struct rbd_device *rbd_dev = q->queuedata;
3191 while ((rq = blk_fetch_request(q))) {
3192 bool write_request = rq_data_dir(rq) == WRITE;
3193 struct rbd_img_request *img_request;
3197 /* Ignore any non-FS requests that filter through. */
3199 if (rq->cmd_type != REQ_TYPE_FS) {
3200 dout("%s: non-fs request type %d\n", __func__,
3201 (int) rq->cmd_type);
3202 __blk_end_request_all(rq, 0);
3206 /* Ignore/skip any zero-length requests */
3208 offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT;
3209 length = (u64) blk_rq_bytes(rq);
3212 dout("%s: zero-length request\n", __func__);
3213 __blk_end_request_all(rq, 0);
3217 spin_unlock_irq(q->queue_lock);
3219 /* Disallow writes to a read-only device */
3221 if (write_request) {
3223 if (rbd_dev->mapping.read_only)
3225 rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP);
3229 * Quit early if the mapped snapshot no longer
3230 * exists. It's still possible the snapshot will
3231 * have disappeared by the time our request arrives
3232 * at the osd, but there's no sense in sending it if
3235 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) {
3236 dout("request for non-existent snapshot");
3237 rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP);
3243 if (offset && length > U64_MAX - offset + 1) {
3244 rbd_warn(rbd_dev, "bad request range (%llu~%llu)\n",
3246 goto end_request; /* Shouldn't happen */
3250 if (offset + length > rbd_dev->mapping.size) {
3251 rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)\n",
3252 offset, length, rbd_dev->mapping.size);
3257 img_request = rbd_img_request_create(rbd_dev, offset, length,
3262 img_request->rq = rq;
3264 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
3267 result = rbd_img_request_submit(img_request);
3269 rbd_img_request_put(img_request);
3271 spin_lock_irq(q->queue_lock);
3273 rbd_warn(rbd_dev, "%s %llx at %llx result %d\n",
3274 write_request ? "write" : "read",
3275 length, offset, result);
3277 __blk_end_request_all(rq, result);
3283 * a queue callback. Makes sure that we don't create a bio that spans across
3284 * multiple osd objects. One exception would be with a single page bios,
3285 * which we handle later at bio_chain_clone_range()
3287 static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
3288 struct bio_vec *bvec)
3290 struct rbd_device *rbd_dev = q->queuedata;
3291 sector_t sector_offset;
3292 sector_t sectors_per_obj;
3293 sector_t obj_sector_offset;
3297 * Find how far into its rbd object the partition-relative
3298 * bio start sector is to offset relative to the enclosing
3301 sector_offset = get_start_sect(bmd->bi_bdev) + bmd->bi_sector;
3302 sectors_per_obj = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT);
3303 obj_sector_offset = sector_offset & (sectors_per_obj - 1);
3306 * Compute the number of bytes from that offset to the end
3307 * of the object. Account for what's already used by the bio.
3309 ret = (int) (sectors_per_obj - obj_sector_offset) << SECTOR_SHIFT;
3310 if (ret > bmd->bi_size)
3311 ret -= bmd->bi_size;
3316 * Don't send back more than was asked for. And if the bio
3317 * was empty, let the whole thing through because: "Note
3318 * that a block device *must* allow a single page to be
3319 * added to an empty bio."
3321 rbd_assert(bvec->bv_len <= PAGE_SIZE);
3322 if (ret > (int) bvec->bv_len || !bmd->bi_size)
3323 ret = (int) bvec->bv_len;
3328 static void rbd_free_disk(struct rbd_device *rbd_dev)
3330 struct gendisk *disk = rbd_dev->disk;
3335 rbd_dev->disk = NULL;
3336 if (disk->flags & GENHD_FL_UP) {
3339 blk_cleanup_queue(disk->queue);
3344 static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
3345 const char *object_name,
3346 u64 offset, u64 length, void *buf)
3349 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3350 struct rbd_obj_request *obj_request;
3351 struct page **pages = NULL;
3356 page_count = (u32) calc_pages_for(offset, length);
3357 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
3359 ret = PTR_ERR(pages);
3362 obj_request = rbd_obj_request_create(object_name, offset, length,
3367 obj_request->pages = pages;
3368 obj_request->page_count = page_count;
3370 obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1,
3372 if (!obj_request->osd_req)
3375 osd_req_op_extent_init(obj_request->osd_req, 0, CEPH_OSD_OP_READ,
3376 offset, length, 0, 0);
3377 osd_req_op_extent_osd_data_pages(obj_request->osd_req, 0,
3379 obj_request->length,
3380 obj_request->offset & ~PAGE_MASK,
3382 rbd_osd_req_format_read(obj_request);
3384 ret = rbd_obj_request_submit(osdc, obj_request);
3387 ret = rbd_obj_request_wait(obj_request);
3391 ret = obj_request->result;
3395 rbd_assert(obj_request->xferred <= (u64) SIZE_MAX);
3396 size = (size_t) obj_request->xferred;
3397 ceph_copy_from_page_vector(pages, buf, 0, size);
3398 rbd_assert(size <= (size_t)INT_MAX);
3402 rbd_obj_request_put(obj_request);
3404 ceph_release_page_vector(pages, page_count);
3410 * Read the complete header for the given rbd device. On successful
3411 * return, the rbd_dev->header field will contain up-to-date
3412 * information about the image.
3414 static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
3416 struct rbd_image_header_ondisk *ondisk = NULL;
3423 * The complete header will include an array of its 64-bit
3424 * snapshot ids, followed by the names of those snapshots as
3425 * a contiguous block of NUL-terminated strings. Note that
3426 * the number of snapshots could change by the time we read
3427 * it in, in which case we re-read it.
3434 size = sizeof (*ondisk);
3435 size += snap_count * sizeof (struct rbd_image_snap_ondisk);
3437 ondisk = kmalloc(size, GFP_KERNEL);
3441 ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name,
3445 if ((size_t)ret < size) {
3447 rbd_warn(rbd_dev, "short header read (want %zd got %d)",
3451 if (!rbd_dev_ondisk_valid(ondisk)) {
3453 rbd_warn(rbd_dev, "invalid header");
3457 names_size = le64_to_cpu(ondisk->snap_names_len);
3458 want_count = snap_count;
3459 snap_count = le32_to_cpu(ondisk->snap_count);
3460 } while (snap_count != want_count);
3462 ret = rbd_header_from_disk(rbd_dev, ondisk);
3470 * Clear the rbd device's EXISTS flag if the snapshot it's mapped to
3471 * has disappeared from the (just updated) snapshot context.
3473 static void rbd_exists_validate(struct rbd_device *rbd_dev)
3477 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags))
3480 snap_id = rbd_dev->spec->snap_id;
3481 if (snap_id == CEPH_NOSNAP)
3484 if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX)
3485 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
3488 static void rbd_dev_update_size(struct rbd_device *rbd_dev)
3494 * Don't hold the lock while doing disk operations,
3495 * or lock ordering will conflict with the bdev mutex via:
3496 * rbd_add() -> blkdev_get() -> rbd_open()
3498 spin_lock_irq(&rbd_dev->lock);
3499 removing = test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags);
3500 spin_unlock_irq(&rbd_dev->lock);
3502 * If the device is being removed, rbd_dev->disk has
3503 * been destroyed, so don't try to update its size
3506 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
3507 dout("setting size to %llu sectors", (unsigned long long)size);
3508 set_capacity(rbd_dev->disk, size);
3509 revalidate_disk(rbd_dev->disk);
3513 static int rbd_dev_refresh(struct rbd_device *rbd_dev)
3518 down_write(&rbd_dev->header_rwsem);
3519 mapping_size = rbd_dev->mapping.size;
3521 ret = rbd_dev_header_info(rbd_dev);
3525 /* If it's a mapped snapshot, validate its EXISTS flag */
3527 rbd_exists_validate(rbd_dev);
3528 up_write(&rbd_dev->header_rwsem);
3530 if (mapping_size != rbd_dev->mapping.size) {
3531 rbd_dev_update_size(rbd_dev);
3537 static int rbd_init_disk(struct rbd_device *rbd_dev)
3539 struct gendisk *disk;
3540 struct request_queue *q;
3543 /* create gendisk info */
3544 disk = alloc_disk(single_major ?
3545 (1 << RBD_SINGLE_MAJOR_PART_SHIFT) :
3546 RBD_MINORS_PER_MAJOR);
3550 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
3552 disk->major = rbd_dev->major;
3553 disk->first_minor = rbd_dev->minor;
3555 disk->flags |= GENHD_FL_EXT_DEVT;
3556 disk->fops = &rbd_bd_ops;
3557 disk->private_data = rbd_dev;
3559 q = blk_init_queue(rbd_request_fn, &rbd_dev->lock);
3563 /* We use the default size, but let's be explicit about it. */
3564 blk_queue_physical_block_size(q, SECTOR_SIZE);
3566 /* set io sizes to object size */
3567 segment_size = rbd_obj_bytes(&rbd_dev->header);
3568 blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
3569 blk_queue_max_segment_size(q, segment_size);
3570 blk_queue_io_min(q, segment_size);
3571 blk_queue_io_opt(q, segment_size);
3573 blk_queue_merge_bvec(q, rbd_merge_bvec);
3576 q->queuedata = rbd_dev;
3578 rbd_dev->disk = disk;
3591 static struct rbd_device *dev_to_rbd_dev(struct device *dev)
3593 return container_of(dev, struct rbd_device, dev);
3596 static ssize_t rbd_size_show(struct device *dev,
3597 struct device_attribute *attr, char *buf)
3599 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3601 return sprintf(buf, "%llu\n",
3602 (unsigned long long)rbd_dev->mapping.size);
3606 * Note this shows the features for whatever's mapped, which is not
3607 * necessarily the base image.
3609 static ssize_t rbd_features_show(struct device *dev,
3610 struct device_attribute *attr, char *buf)
3612 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3614 return sprintf(buf, "0x%016llx\n",
3615 (unsigned long long)rbd_dev->mapping.features);
3618 static ssize_t rbd_major_show(struct device *dev,
3619 struct device_attribute *attr, char *buf)
3621 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3624 return sprintf(buf, "%d\n", rbd_dev->major);
3626 return sprintf(buf, "(none)\n");
3629 static ssize_t rbd_minor_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, "%d\n", rbd_dev->minor);
3637 static ssize_t rbd_client_id_show(struct device *dev,
3638 struct device_attribute *attr, char *buf)
3640 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3642 return sprintf(buf, "client%lld\n",
3643 ceph_client_id(rbd_dev->rbd_client->client));
3646 static ssize_t rbd_pool_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, "%s\n", rbd_dev->spec->pool_name);
3654 static ssize_t rbd_pool_id_show(struct device *dev,
3655 struct device_attribute *attr, char *buf)
3657 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3659 return sprintf(buf, "%llu\n",
3660 (unsigned long long) rbd_dev->spec->pool_id);
3663 static ssize_t rbd_name_show(struct device *dev,
3664 struct device_attribute *attr, char *buf)
3666 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3668 if (rbd_dev->spec->image_name)
3669 return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
3671 return sprintf(buf, "(unknown)\n");
3674 static ssize_t rbd_image_id_show(struct device *dev,
3675 struct device_attribute *attr, char *buf)
3677 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3679 return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
3683 * Shows the name of the currently-mapped snapshot (or
3684 * RBD_SNAP_HEAD_NAME for the base image).
3686 static ssize_t rbd_snap_show(struct device *dev,
3687 struct device_attribute *attr,
3690 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3692 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
3696 * For a v2 image, shows the chain of parent images, separated by empty
3697 * lines. For v1 images or if there is no parent, shows "(no parent
3700 static ssize_t rbd_parent_show(struct device *dev,
3701 struct device_attribute *attr,
3704 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3707 if (!rbd_dev->parent)
3708 return sprintf(buf, "(no parent image)\n");
3710 for ( ; rbd_dev->parent; rbd_dev = rbd_dev->parent) {
3711 struct rbd_spec *spec = rbd_dev->parent_spec;
3713 count += sprintf(&buf[count], "%s"
3714 "pool_id %llu\npool_name %s\n"
3715 "image_id %s\nimage_name %s\n"
3716 "snap_id %llu\nsnap_name %s\n"
3718 !count ? "" : "\n", /* first? */
3719 spec->pool_id, spec->pool_name,
3720 spec->image_id, spec->image_name ?: "(unknown)",
3721 spec->snap_id, spec->snap_name,
3722 rbd_dev->parent_overlap);
3728 static ssize_t rbd_image_refresh(struct device *dev,
3729 struct device_attribute *attr,
3733 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3736 ret = rbd_dev_refresh(rbd_dev);
3743 static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
3744 static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL);
3745 static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
3746 static DEVICE_ATTR(minor, S_IRUGO, rbd_minor_show, NULL);
3747 static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
3748 static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
3749 static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL);
3750 static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
3751 static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL);
3752 static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
3753 static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
3754 static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL);
3756 static struct attribute *rbd_attrs[] = {
3757 &dev_attr_size.attr,
3758 &dev_attr_features.attr,
3759 &dev_attr_major.attr,
3760 &dev_attr_minor.attr,
3761 &dev_attr_client_id.attr,
3762 &dev_attr_pool.attr,
3763 &dev_attr_pool_id.attr,
3764 &dev_attr_name.attr,
3765 &dev_attr_image_id.attr,
3766 &dev_attr_current_snap.attr,
3767 &dev_attr_parent.attr,
3768 &dev_attr_refresh.attr,
3772 static struct attribute_group rbd_attr_group = {
3776 static const struct attribute_group *rbd_attr_groups[] = {
3781 static void rbd_sysfs_dev_release(struct device *dev)
3785 static struct device_type rbd_device_type = {
3787 .groups = rbd_attr_groups,
3788 .release = rbd_sysfs_dev_release,
3791 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
3793 kref_get(&spec->kref);
3798 static void rbd_spec_free(struct kref *kref);
3799 static void rbd_spec_put(struct rbd_spec *spec)
3802 kref_put(&spec->kref, rbd_spec_free);
3805 static struct rbd_spec *rbd_spec_alloc(void)
3807 struct rbd_spec *spec;
3809 spec = kzalloc(sizeof (*spec), GFP_KERNEL);
3813 spec->pool_id = CEPH_NOPOOL;
3814 spec->snap_id = CEPH_NOSNAP;
3815 kref_init(&spec->kref);
3820 static void rbd_spec_free(struct kref *kref)
3822 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
3824 kfree(spec->pool_name);
3825 kfree(spec->image_id);
3826 kfree(spec->image_name);
3827 kfree(spec->snap_name);
3831 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
3832 struct rbd_spec *spec)
3834 struct rbd_device *rbd_dev;
3836 rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL);
3840 spin_lock_init(&rbd_dev->lock);
3842 atomic_set(&rbd_dev->parent_ref, 0);
3843 INIT_LIST_HEAD(&rbd_dev->node);
3844 init_rwsem(&rbd_dev->header_rwsem);
3846 rbd_dev->spec = spec;
3847 rbd_dev->rbd_client = rbdc;
3849 /* Initialize the layout used for all rbd requests */
3851 rbd_dev->layout.fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3852 rbd_dev->layout.fl_stripe_count = cpu_to_le32(1);
3853 rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
3854 rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id);
3859 static void rbd_dev_destroy(struct rbd_device *rbd_dev)
3861 rbd_put_client(rbd_dev->rbd_client);
3862 rbd_spec_put(rbd_dev->spec);
3867 * Get the size and object order for an image snapshot, or if
3868 * snap_id is CEPH_NOSNAP, gets this information for the base
3871 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
3872 u8 *order, u64 *snap_size)
3874 __le64 snapid = cpu_to_le64(snap_id);
3879 } __attribute__ ((packed)) size_buf = { 0 };
3881 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3883 &snapid, sizeof (snapid),
3884 &size_buf, sizeof (size_buf));
3885 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3888 if (ret < sizeof (size_buf))
3892 *order = size_buf.order;
3893 dout(" order %u", (unsigned int)*order);
3895 *snap_size = le64_to_cpu(size_buf.size);
3897 dout(" snap_id 0x%016llx snap_size = %llu\n",
3898 (unsigned long long)snap_id,
3899 (unsigned long long)*snap_size);
3904 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
3906 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
3907 &rbd_dev->header.obj_order,
3908 &rbd_dev->header.image_size);
3911 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
3917 reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL);
3921 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3922 "rbd", "get_object_prefix", NULL, 0,
3923 reply_buf, RBD_OBJ_PREFIX_LEN_MAX);
3924 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3929 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
3930 p + ret, NULL, GFP_NOIO);
3933 if (IS_ERR(rbd_dev->header.object_prefix)) {
3934 ret = PTR_ERR(rbd_dev->header.object_prefix);
3935 rbd_dev->header.object_prefix = NULL;
3937 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix);
3945 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
3948 __le64 snapid = cpu_to_le64(snap_id);
3952 } __attribute__ ((packed)) features_buf = { 0 };
3956 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
3957 "rbd", "get_features",
3958 &snapid, sizeof (snapid),
3959 &features_buf, sizeof (features_buf));
3960 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
3963 if (ret < sizeof (features_buf))
3966 incompat = le64_to_cpu(features_buf.incompat);
3967 if (incompat & ~RBD_FEATURES_SUPPORTED)
3970 *snap_features = le64_to_cpu(features_buf.features);
3972 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
3973 (unsigned long long)snap_id,
3974 (unsigned long long)*snap_features,
3975 (unsigned long long)le64_to_cpu(features_buf.incompat));
3980 static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
3982 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
3983 &rbd_dev->header.features);
3986 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
3988 struct rbd_spec *parent_spec;
3990 void *reply_buf = NULL;
4000 parent_spec = rbd_spec_alloc();
4004 size = sizeof (__le64) + /* pool_id */
4005 sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */
4006 sizeof (__le64) + /* snap_id */
4007 sizeof (__le64); /* overlap */
4008 reply_buf = kmalloc(size, GFP_KERNEL);
4014 snapid = cpu_to_le64(CEPH_NOSNAP);
4015 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4016 "rbd", "get_parent",
4017 &snapid, sizeof (snapid),
4019 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4024 end = reply_buf + ret;
4026 ceph_decode_64_safe(&p, end, pool_id, out_err);
4027 if (pool_id == CEPH_NOPOOL) {
4029 * Either the parent never existed, or we have
4030 * record of it but the image got flattened so it no
4031 * longer has a parent. When the parent of a
4032 * layered image disappears we immediately set the
4033 * overlap to 0. The effect of this is that all new
4034 * requests will be treated as if the image had no
4037 if (rbd_dev->parent_overlap) {
4038 rbd_dev->parent_overlap = 0;
4040 rbd_dev_parent_put(rbd_dev);
4041 pr_info("%s: clone image has been flattened\n",
4042 rbd_dev->disk->disk_name);
4045 goto out; /* No parent? No problem. */
4048 /* The ceph file layout needs to fit pool id in 32 bits */
4051 if (pool_id > (u64)U32_MAX) {
4052 rbd_warn(NULL, "parent pool id too large (%llu > %u)\n",
4053 (unsigned long long)pool_id, U32_MAX);
4057 image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
4058 if (IS_ERR(image_id)) {
4059 ret = PTR_ERR(image_id);
4062 ceph_decode_64_safe(&p, end, snap_id, out_err);
4063 ceph_decode_64_safe(&p, end, overlap, out_err);
4066 * The parent won't change (except when the clone is
4067 * flattened, already handled that). So we only need to
4068 * record the parent spec we have not already done so.
4070 if (!rbd_dev->parent_spec) {
4071 parent_spec->pool_id = pool_id;
4072 parent_spec->image_id = image_id;
4073 parent_spec->snap_id = snap_id;
4074 rbd_dev->parent_spec = parent_spec;
4075 parent_spec = NULL; /* rbd_dev now owns this */
4081 * We always update the parent overlap. If it's zero we
4082 * treat it specially.
4084 rbd_dev->parent_overlap = overlap;
4088 /* A null parent_spec indicates it's the initial probe */
4092 * The overlap has become zero, so the clone
4093 * must have been resized down to 0 at some
4094 * point. Treat this the same as a flatten.
4096 rbd_dev_parent_put(rbd_dev);
4097 pr_info("%s: clone image now standalone\n",
4098 rbd_dev->disk->disk_name);
4101 * For the initial probe, if we find the
4102 * overlap is zero we just pretend there was
4105 rbd_warn(rbd_dev, "ignoring parent of "
4106 "clone with overlap 0\n");
4113 rbd_spec_put(parent_spec);
4118 static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
4122 __le64 stripe_count;
4123 } __attribute__ ((packed)) striping_info_buf = { 0 };
4124 size_t size = sizeof (striping_info_buf);
4131 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4132 "rbd", "get_stripe_unit_count", NULL, 0,
4133 (char *)&striping_info_buf, size);
4134 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4141 * We don't actually support the "fancy striping" feature
4142 * (STRIPINGV2) yet, but if the striping sizes are the
4143 * defaults the behavior is the same as before. So find
4144 * out, and only fail if the image has non-default values.
4147 obj_size = (u64)1 << rbd_dev->header.obj_order;
4148 p = &striping_info_buf;
4149 stripe_unit = ceph_decode_64(&p);
4150 if (stripe_unit != obj_size) {
4151 rbd_warn(rbd_dev, "unsupported stripe unit "
4152 "(got %llu want %llu)",
4153 stripe_unit, obj_size);
4156 stripe_count = ceph_decode_64(&p);
4157 if (stripe_count != 1) {
4158 rbd_warn(rbd_dev, "unsupported stripe count "
4159 "(got %llu want 1)", stripe_count);
4162 rbd_dev->header.stripe_unit = stripe_unit;
4163 rbd_dev->header.stripe_count = stripe_count;
4168 static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
4170 size_t image_id_size;
4175 void *reply_buf = NULL;
4177 char *image_name = NULL;
4180 rbd_assert(!rbd_dev->spec->image_name);
4182 len = strlen(rbd_dev->spec->image_id);
4183 image_id_size = sizeof (__le32) + len;
4184 image_id = kmalloc(image_id_size, GFP_KERNEL);
4189 end = image_id + image_id_size;
4190 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
4192 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
4193 reply_buf = kmalloc(size, GFP_KERNEL);
4197 ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY,
4198 "rbd", "dir_get_name",
4199 image_id, image_id_size,
4204 end = reply_buf + ret;
4206 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
4207 if (IS_ERR(image_name))
4210 dout("%s: name is %s len is %zd\n", __func__, image_name, len);
4218 static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4220 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
4221 const char *snap_name;
4224 /* Skip over names until we find the one we are looking for */
4226 snap_name = rbd_dev->header.snap_names;
4227 while (which < snapc->num_snaps) {
4228 if (!strcmp(name, snap_name))
4229 return snapc->snaps[which];
4230 snap_name += strlen(snap_name) + 1;
4236 static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4238 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
4243 for (which = 0; !found && which < snapc->num_snaps; which++) {
4244 const char *snap_name;
4246 snap_id = snapc->snaps[which];
4247 snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
4248 if (IS_ERR(snap_name)) {
4249 /* ignore no-longer existing snapshots */
4250 if (PTR_ERR(snap_name) == -ENOENT)
4255 found = !strcmp(name, snap_name);
4258 return found ? snap_id : CEPH_NOSNAP;
4262 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
4263 * no snapshot by that name is found, or if an error occurs.
4265 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4267 if (rbd_dev->image_format == 1)
4268 return rbd_v1_snap_id_by_name(rbd_dev, name);
4270 return rbd_v2_snap_id_by_name(rbd_dev, name);
4274 * An image being mapped will have everything but the snap id.
4276 static int rbd_spec_fill_snap_id(struct rbd_device *rbd_dev)
4278 struct rbd_spec *spec = rbd_dev->spec;
4280 rbd_assert(spec->pool_id != CEPH_NOPOOL && spec->pool_name);
4281 rbd_assert(spec->image_id && spec->image_name);
4282 rbd_assert(spec->snap_name);
4284 if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
4287 snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
4288 if (snap_id == CEPH_NOSNAP)
4291 spec->snap_id = snap_id;
4293 spec->snap_id = CEPH_NOSNAP;
4300 * A parent image will have all ids but none of the names.
4302 * All names in an rbd spec are dynamically allocated. It's OK if we
4303 * can't figure out the name for an image id.
4305 static int rbd_spec_fill_names(struct rbd_device *rbd_dev)
4307 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4308 struct rbd_spec *spec = rbd_dev->spec;
4309 const char *pool_name;
4310 const char *image_name;
4311 const char *snap_name;
4314 rbd_assert(spec->pool_id != CEPH_NOPOOL);
4315 rbd_assert(spec->image_id);
4316 rbd_assert(spec->snap_id != CEPH_NOSNAP);
4318 /* Get the pool name; we have to make our own copy of this */
4320 pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
4322 rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
4325 pool_name = kstrdup(pool_name, GFP_KERNEL);
4329 /* Fetch the image name; tolerate failure here */
4331 image_name = rbd_dev_image_name(rbd_dev);
4333 rbd_warn(rbd_dev, "unable to get image name");
4335 /* Fetch the snapshot name */
4337 snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
4338 if (IS_ERR(snap_name)) {
4339 ret = PTR_ERR(snap_name);
4343 spec->pool_name = pool_name;
4344 spec->image_name = image_name;
4345 spec->snap_name = snap_name;
4355 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
4364 struct ceph_snap_context *snapc;
4368 * We'll need room for the seq value (maximum snapshot id),
4369 * snapshot count, and array of that many snapshot ids.
4370 * For now we have a fixed upper limit on the number we're
4371 * prepared to receive.
4373 size = sizeof (__le64) + sizeof (__le32) +
4374 RBD_MAX_SNAP_COUNT * sizeof (__le64);
4375 reply_buf = kzalloc(size, GFP_KERNEL);
4379 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4380 "rbd", "get_snapcontext", NULL, 0,
4382 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4387 end = reply_buf + ret;
4389 ceph_decode_64_safe(&p, end, seq, out);
4390 ceph_decode_32_safe(&p, end, snap_count, out);
4393 * Make sure the reported number of snapshot ids wouldn't go
4394 * beyond the end of our buffer. But before checking that,
4395 * make sure the computed size of the snapshot context we
4396 * allocate is representable in a size_t.
4398 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
4403 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
4407 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
4413 for (i = 0; i < snap_count; i++)
4414 snapc->snaps[i] = ceph_decode_64(&p);
4416 ceph_put_snap_context(rbd_dev->header.snapc);
4417 rbd_dev->header.snapc = snapc;
4419 dout(" snap context seq = %llu, snap_count = %u\n",
4420 (unsigned long long)seq, (unsigned int)snap_count);
4427 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
4438 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
4439 reply_buf = kmalloc(size, GFP_KERNEL);
4441 return ERR_PTR(-ENOMEM);
4443 snapid = cpu_to_le64(snap_id);
4444 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4445 "rbd", "get_snapshot_name",
4446 &snapid, sizeof (snapid),
4448 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4450 snap_name = ERR_PTR(ret);
4455 end = reply_buf + ret;
4456 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
4457 if (IS_ERR(snap_name))
4460 dout(" snap_id 0x%016llx snap_name = %s\n",
4461 (unsigned long long)snap_id, snap_name);
4468 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
4470 bool first_time = rbd_dev->header.object_prefix == NULL;
4473 ret = rbd_dev_v2_image_size(rbd_dev);
4478 ret = rbd_dev_v2_header_onetime(rbd_dev);
4484 * If the image supports layering, get the parent info. We
4485 * need to probe the first time regardless. Thereafter we
4486 * only need to if there's a parent, to see if it has
4487 * disappeared due to the mapped image getting flattened.
4489 if (rbd_dev->header.features & RBD_FEATURE_LAYERING &&
4490 (first_time || rbd_dev->parent_spec)) {
4493 ret = rbd_dev_v2_parent_info(rbd_dev);
4498 * Print a warning if this is the initial probe and
4499 * the image has a parent. Don't print it if the
4500 * image now being probed is itself a parent. We
4501 * can tell at this point because we won't know its
4502 * pool name yet (just its pool id).
4504 warn = rbd_dev->parent_spec && rbd_dev->spec->pool_name;
4505 if (first_time && warn)
4506 rbd_warn(rbd_dev, "WARNING: kernel layering "
4507 "is EXPERIMENTAL!");
4510 if (rbd_dev->spec->snap_id == CEPH_NOSNAP)
4511 if (rbd_dev->mapping.size != rbd_dev->header.image_size)
4512 rbd_dev->mapping.size = rbd_dev->header.image_size;
4514 ret = rbd_dev_v2_snap_context(rbd_dev);
4515 dout("rbd_dev_v2_snap_context returned %d\n", ret);
4520 static int rbd_dev_header_info(struct rbd_device *rbd_dev)
4522 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
4524 if (rbd_dev->image_format == 1)
4525 return rbd_dev_v1_header_info(rbd_dev);
4527 return rbd_dev_v2_header_info(rbd_dev);
4530 static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
4535 dev = &rbd_dev->dev;
4536 dev->bus = &rbd_bus_type;
4537 dev->type = &rbd_device_type;
4538 dev->parent = &rbd_root_dev;
4539 dev->release = rbd_dev_device_release;
4540 dev_set_name(dev, "%d", rbd_dev->dev_id);
4541 ret = device_register(dev);
4546 static void rbd_bus_del_dev(struct rbd_device *rbd_dev)
4548 device_unregister(&rbd_dev->dev);
4552 * Get a unique rbd identifier for the given new rbd_dev, and add
4553 * the rbd_dev to the global list.
4555 static int rbd_dev_id_get(struct rbd_device *rbd_dev)
4559 new_dev_id = ida_simple_get(&rbd_dev_id_ida,
4560 0, minor_to_rbd_dev_id(1 << MINORBITS),
4565 rbd_dev->dev_id = new_dev_id;
4567 spin_lock(&rbd_dev_list_lock);
4568 list_add_tail(&rbd_dev->node, &rbd_dev_list);
4569 spin_unlock(&rbd_dev_list_lock);
4571 dout("rbd_dev %p given dev id %d\n", rbd_dev, rbd_dev->dev_id);
4577 * Remove an rbd_dev from the global list, and record that its
4578 * identifier is no longer in use.
4580 static void rbd_dev_id_put(struct rbd_device *rbd_dev)
4582 spin_lock(&rbd_dev_list_lock);
4583 list_del_init(&rbd_dev->node);
4584 spin_unlock(&rbd_dev_list_lock);
4586 ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id);
4588 dout("rbd_dev %p released dev id %d\n", rbd_dev, rbd_dev->dev_id);
4592 * Skips over white space at *buf, and updates *buf to point to the
4593 * first found non-space character (if any). Returns the length of
4594 * the token (string of non-white space characters) found. Note
4595 * that *buf must be terminated with '\0'.
4597 static inline size_t next_token(const char **buf)
4600 * These are the characters that produce nonzero for
4601 * isspace() in the "C" and "POSIX" locales.
4603 const char *spaces = " \f\n\r\t\v";
4605 *buf += strspn(*buf, spaces); /* Find start of token */
4607 return strcspn(*buf, spaces); /* Return token length */
4611 * Finds the next token in *buf, and if the provided token buffer is
4612 * big enough, copies the found token into it. The result, if
4613 * copied, is guaranteed to be terminated with '\0'. Note that *buf
4614 * must be terminated with '\0' on entry.
4616 * Returns the length of the token found (not including the '\0').
4617 * Return value will be 0 if no token is found, and it will be >=
4618 * token_size if the token would not fit.
4620 * The *buf pointer will be updated to point beyond the end of the
4621 * found token. Note that this occurs even if the token buffer is
4622 * too small to hold it.
4624 static inline size_t copy_token(const char **buf,
4630 len = next_token(buf);
4631 if (len < token_size) {
4632 memcpy(token, *buf, len);
4633 *(token + len) = '\0';
4641 * Finds the next token in *buf, dynamically allocates a buffer big
4642 * enough to hold a copy of it, and copies the token into the new
4643 * buffer. The copy is guaranteed to be terminated with '\0'. Note
4644 * that a duplicate buffer is created even for a zero-length token.
4646 * Returns a pointer to the newly-allocated duplicate, or a null
4647 * pointer if memory for the duplicate was not available. If
4648 * the lenp argument is a non-null pointer, the length of the token
4649 * (not including the '\0') is returned in *lenp.
4651 * If successful, the *buf pointer will be updated to point beyond
4652 * the end of the found token.
4654 * Note: uses GFP_KERNEL for allocation.
4656 static inline char *dup_token(const char **buf, size_t *lenp)
4661 len = next_token(buf);
4662 dup = kmemdup(*buf, len + 1, GFP_KERNEL);
4665 *(dup + len) = '\0';
4675 * Parse the options provided for an "rbd add" (i.e., rbd image
4676 * mapping) request. These arrive via a write to /sys/bus/rbd/add,
4677 * and the data written is passed here via a NUL-terminated buffer.
4678 * Returns 0 if successful or an error code otherwise.
4680 * The information extracted from these options is recorded in
4681 * the other parameters which return dynamically-allocated
4684 * The address of a pointer that will refer to a ceph options
4685 * structure. Caller must release the returned pointer using
4686 * ceph_destroy_options() when it is no longer needed.
4688 * Address of an rbd options pointer. Fully initialized by
4689 * this function; caller must release with kfree().
4691 * Address of an rbd image specification pointer. Fully
4692 * initialized by this function based on parsed options.
4693 * Caller must release with rbd_spec_put().
4695 * The options passed take this form:
4696 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
4699 * A comma-separated list of one or more monitor addresses.
4700 * A monitor address is an ip address, optionally followed
4701 * by a port number (separated by a colon).
4702 * I.e.: ip1[:port1][,ip2[:port2]...]
4704 * A comma-separated list of ceph and/or rbd options.
4706 * The name of the rados pool containing the rbd image.
4708 * The name of the image in that pool to map.
4710 * An optional snapshot id. If provided, the mapping will
4711 * present data from the image at the time that snapshot was
4712 * created. The image head is used if no snapshot id is
4713 * provided. Snapshot mappings are always read-only.
4715 static int rbd_add_parse_args(const char *buf,
4716 struct ceph_options **ceph_opts,
4717 struct rbd_options **opts,
4718 struct rbd_spec **rbd_spec)
4722 const char *mon_addrs;
4724 size_t mon_addrs_size;
4725 struct rbd_spec *spec = NULL;
4726 struct rbd_options *rbd_opts = NULL;
4727 struct ceph_options *copts;
4730 /* The first four tokens are required */
4732 len = next_token(&buf);
4734 rbd_warn(NULL, "no monitor address(es) provided");
4738 mon_addrs_size = len + 1;
4742 options = dup_token(&buf, NULL);
4746 rbd_warn(NULL, "no options provided");
4750 spec = rbd_spec_alloc();
4754 spec->pool_name = dup_token(&buf, NULL);
4755 if (!spec->pool_name)
4757 if (!*spec->pool_name) {
4758 rbd_warn(NULL, "no pool name provided");
4762 spec->image_name = dup_token(&buf, NULL);
4763 if (!spec->image_name)
4765 if (!*spec->image_name) {
4766 rbd_warn(NULL, "no image name provided");
4771 * Snapshot name is optional; default is to use "-"
4772 * (indicating the head/no snapshot).
4774 len = next_token(&buf);
4776 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
4777 len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
4778 } else if (len > RBD_MAX_SNAP_NAME_LEN) {
4779 ret = -ENAMETOOLONG;
4782 snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
4785 *(snap_name + len) = '\0';
4786 spec->snap_name = snap_name;
4788 /* Initialize all rbd options to the defaults */
4790 rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL);
4794 rbd_opts->read_only = RBD_READ_ONLY_DEFAULT;
4796 copts = ceph_parse_options(options, mon_addrs,
4797 mon_addrs + mon_addrs_size - 1,
4798 parse_rbd_opts_token, rbd_opts);
4799 if (IS_ERR(copts)) {
4800 ret = PTR_ERR(copts);
4821 * Return pool id (>= 0) or a negative error code.
4823 static int rbd_add_get_pool_id(struct rbd_client *rbdc, const char *pool_name)
4826 unsigned long timeout = rbdc->client->options->mount_timeout * HZ;
4831 ret = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, pool_name);
4832 if (ret == -ENOENT && tries++ < 1) {
4833 ret = ceph_monc_do_get_version(&rbdc->client->monc, "osdmap",
4838 if (rbdc->client->osdc.osdmap->epoch < newest_epoch) {
4839 ceph_monc_request_next_osdmap(&rbdc->client->monc);
4840 (void) ceph_monc_wait_osdmap(&rbdc->client->monc,
4841 newest_epoch, timeout);
4844 /* the osdmap we have is new enough */
4853 * An rbd format 2 image has a unique identifier, distinct from the
4854 * name given to it by the user. Internally, that identifier is
4855 * what's used to specify the names of objects related to the image.
4857 * A special "rbd id" object is used to map an rbd image name to its
4858 * id. If that object doesn't exist, then there is no v2 rbd image
4859 * with the supplied name.
4861 * This function will record the given rbd_dev's image_id field if
4862 * it can be determined, and in that case will return 0. If any
4863 * errors occur a negative errno will be returned and the rbd_dev's
4864 * image_id field will be unchanged (and should be NULL).
4866 static int rbd_dev_image_id(struct rbd_device *rbd_dev)
4875 * When probing a parent image, the image id is already
4876 * known (and the image name likely is not). There's no
4877 * need to fetch the image id again in this case. We
4878 * do still need to set the image format though.
4880 if (rbd_dev->spec->image_id) {
4881 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;
4887 * First, see if the format 2 image id file exists, and if
4888 * so, get the image's persistent id from it.
4890 size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name);
4891 object_name = kmalloc(size, GFP_NOIO);
4894 sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name);
4895 dout("rbd id object name is %s\n", object_name);
4897 /* Response will be an encoded string, which includes a length */
4899 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
4900 response = kzalloc(size, GFP_NOIO);
4906 /* If it doesn't exist we'll assume it's a format 1 image */
4908 ret = rbd_obj_method_sync(rbd_dev, object_name,
4909 "rbd", "get_id", NULL, 0,
4910 response, RBD_IMAGE_ID_LEN_MAX);
4911 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4912 if (ret == -ENOENT) {
4913 image_id = kstrdup("", GFP_KERNEL);
4914 ret = image_id ? 0 : -ENOMEM;
4916 rbd_dev->image_format = 1;
4917 } else if (ret > sizeof (__le32)) {
4920 image_id = ceph_extract_encoded_string(&p, p + ret,
4922 ret = PTR_ERR_OR_ZERO(image_id);
4924 rbd_dev->image_format = 2;
4930 rbd_dev->spec->image_id = image_id;
4931 dout("image_id is %s\n", image_id);
4941 * Undo whatever state changes are made by v1 or v2 header info
4944 static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
4946 struct rbd_image_header *header;
4948 /* Drop parent reference unless it's already been done (or none) */
4950 if (rbd_dev->parent_overlap)
4951 rbd_dev_parent_put(rbd_dev);
4953 /* Free dynamic fields from the header, then zero it out */
4955 header = &rbd_dev->header;
4956 ceph_put_snap_context(header->snapc);
4957 kfree(header->snap_sizes);
4958 kfree(header->snap_names);
4959 kfree(header->object_prefix);
4960 memset(header, 0, sizeof (*header));
4963 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev)
4967 ret = rbd_dev_v2_object_prefix(rbd_dev);
4972 * Get the and check features for the image. Currently the
4973 * features are assumed to never change.
4975 ret = rbd_dev_v2_features(rbd_dev);
4979 /* If the image supports fancy striping, get its parameters */
4981 if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
4982 ret = rbd_dev_v2_striping_info(rbd_dev);
4986 /* No support for crypto and compression type format 2 images */
4990 rbd_dev->header.features = 0;
4991 kfree(rbd_dev->header.object_prefix);
4992 rbd_dev->header.object_prefix = NULL;
4997 static int rbd_dev_probe_parent(struct rbd_device *rbd_dev)
4999 struct rbd_device *parent = NULL;
5000 struct rbd_spec *parent_spec;
5001 struct rbd_client *rbdc;
5004 if (!rbd_dev->parent_spec)
5007 * We need to pass a reference to the client and the parent
5008 * spec when creating the parent rbd_dev. Images related by
5009 * parent/child relationships always share both.
5011 parent_spec = rbd_spec_get(rbd_dev->parent_spec);
5012 rbdc = __rbd_get_client(rbd_dev->rbd_client);
5015 parent = rbd_dev_create(rbdc, parent_spec);
5019 ret = rbd_dev_image_probe(parent, false);
5022 rbd_dev->parent = parent;
5023 atomic_set(&rbd_dev->parent_ref, 1);
5028 rbd_dev_unparent(rbd_dev);
5029 kfree(rbd_dev->header_name);
5030 rbd_dev_destroy(parent);
5032 rbd_put_client(rbdc);
5033 rbd_spec_put(parent_spec);
5039 static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
5043 /* Get an id and fill in device name. */
5045 ret = rbd_dev_id_get(rbd_dev);
5049 BUILD_BUG_ON(DEV_NAME_LEN
5050 < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
5051 sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id);
5053 /* Record our major and minor device numbers. */
5055 if (!single_major) {
5056 ret = register_blkdev(0, rbd_dev->name);
5060 rbd_dev->major = ret;
5063 rbd_dev->major = rbd_major;
5064 rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id);
5067 /* Set up the blkdev mapping. */
5069 ret = rbd_init_disk(rbd_dev);
5071 goto err_out_blkdev;
5073 ret = rbd_dev_mapping_set(rbd_dev);
5076 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
5077 set_disk_ro(rbd_dev->disk, rbd_dev->mapping.read_only);
5079 ret = rbd_bus_add_dev(rbd_dev);
5081 goto err_out_mapping;
5083 /* Everything's ready. Announce the disk to the world. */
5085 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
5086 add_disk(rbd_dev->disk);
5088 pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name,
5089 (unsigned long long) rbd_dev->mapping.size);
5094 rbd_dev_mapping_clear(rbd_dev);
5096 rbd_free_disk(rbd_dev);
5099 unregister_blkdev(rbd_dev->major, rbd_dev->name);
5101 rbd_dev_id_put(rbd_dev);
5102 rbd_dev_mapping_clear(rbd_dev);
5107 static int rbd_dev_header_name(struct rbd_device *rbd_dev)
5109 struct rbd_spec *spec = rbd_dev->spec;
5112 /* Record the header object name for this rbd image. */
5114 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
5116 if (rbd_dev->image_format == 1)
5117 size = strlen(spec->image_name) + sizeof (RBD_SUFFIX);
5119 size = sizeof (RBD_HEADER_PREFIX) + strlen(spec->image_id);
5121 rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
5122 if (!rbd_dev->header_name)
5125 if (rbd_dev->image_format == 1)
5126 sprintf(rbd_dev->header_name, "%s%s",
5127 spec->image_name, RBD_SUFFIX);
5129 sprintf(rbd_dev->header_name, "%s%s",
5130 RBD_HEADER_PREFIX, spec->image_id);
5134 static void rbd_dev_image_release(struct rbd_device *rbd_dev)
5136 rbd_dev_unprobe(rbd_dev);
5137 kfree(rbd_dev->header_name);
5138 rbd_dev->header_name = NULL;
5139 rbd_dev->image_format = 0;
5140 kfree(rbd_dev->spec->image_id);
5141 rbd_dev->spec->image_id = NULL;
5143 rbd_dev_destroy(rbd_dev);
5147 * Probe for the existence of the header object for the given rbd
5148 * device. If this image is the one being mapped (i.e., not a
5149 * parent), initiate a watch on its header object before using that
5150 * object to get detailed information about the rbd image.
5152 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping)
5157 * Get the id from the image id object. Unless there's an
5158 * error, rbd_dev->spec->image_id will be filled in with
5159 * a dynamically-allocated string, and rbd_dev->image_format
5160 * will be set to either 1 or 2.
5162 ret = rbd_dev_image_id(rbd_dev);
5166 ret = rbd_dev_header_name(rbd_dev);
5168 goto err_out_format;
5171 ret = rbd_dev_header_watch_sync(rbd_dev);
5173 goto out_header_name;
5176 ret = rbd_dev_header_info(rbd_dev);
5181 * If this image is the one being mapped, we have pool name and
5182 * id, image name and id, and snap name - need to fill snap id.
5183 * Otherwise this is a parent image, identified by pool, image
5184 * and snap ids - need to fill in names for those ids.
5187 ret = rbd_spec_fill_snap_id(rbd_dev);
5189 ret = rbd_spec_fill_names(rbd_dev);
5193 ret = rbd_dev_probe_parent(rbd_dev);
5197 dout("discovered format %u image, header name is %s\n",
5198 rbd_dev->image_format, rbd_dev->header_name);
5202 rbd_dev_unprobe(rbd_dev);
5205 rbd_dev_header_unwatch_sync(rbd_dev);
5207 kfree(rbd_dev->header_name);
5208 rbd_dev->header_name = NULL;
5210 rbd_dev->image_format = 0;
5211 kfree(rbd_dev->spec->image_id);
5212 rbd_dev->spec->image_id = NULL;
5214 dout("probe failed, returning %d\n", ret);
5219 static ssize_t do_rbd_add(struct bus_type *bus,
5223 struct rbd_device *rbd_dev = NULL;
5224 struct ceph_options *ceph_opts = NULL;
5225 struct rbd_options *rbd_opts = NULL;
5226 struct rbd_spec *spec = NULL;
5227 struct rbd_client *rbdc;
5231 if (!try_module_get(THIS_MODULE))
5234 /* parse add command */
5235 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
5237 goto err_out_module;
5238 read_only = rbd_opts->read_only;
5240 rbd_opts = NULL; /* done with this */
5242 rbdc = rbd_get_client(ceph_opts);
5249 rc = rbd_add_get_pool_id(rbdc, spec->pool_name);
5251 goto err_out_client;
5252 spec->pool_id = (u64)rc;
5254 /* The ceph file layout needs to fit pool id in 32 bits */
5256 if (spec->pool_id > (u64)U32_MAX) {
5257 rbd_warn(NULL, "pool id too large (%llu > %u)\n",
5258 (unsigned long long)spec->pool_id, U32_MAX);
5260 goto err_out_client;
5263 rbd_dev = rbd_dev_create(rbdc, spec);
5265 goto err_out_client;
5266 rbdc = NULL; /* rbd_dev now owns this */
5267 spec = NULL; /* rbd_dev now owns this */
5269 rc = rbd_dev_image_probe(rbd_dev, true);
5271 goto err_out_rbd_dev;
5273 /* If we are mapping a snapshot it must be marked read-only */
5275 if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
5277 rbd_dev->mapping.read_only = read_only;
5279 rc = rbd_dev_device_setup(rbd_dev);
5282 * rbd_dev_header_unwatch_sync() can't be moved into
5283 * rbd_dev_image_release() without refactoring, see
5284 * commit 1f3ef78861ac.
5286 rbd_dev_header_unwatch_sync(rbd_dev);
5287 rbd_dev_image_release(rbd_dev);
5288 goto err_out_module;
5294 rbd_dev_destroy(rbd_dev);
5296 rbd_put_client(rbdc);
5300 module_put(THIS_MODULE);
5302 dout("Error adding device %s\n", buf);
5307 static ssize_t rbd_add(struct bus_type *bus,
5314 return do_rbd_add(bus, buf, count);
5317 static ssize_t rbd_add_single_major(struct bus_type *bus,
5321 return do_rbd_add(bus, buf, count);
5324 static void rbd_dev_device_release(struct device *dev)
5326 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5328 rbd_free_disk(rbd_dev);
5329 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
5330 rbd_dev_mapping_clear(rbd_dev);
5332 unregister_blkdev(rbd_dev->major, rbd_dev->name);
5333 rbd_dev_id_put(rbd_dev);
5334 rbd_dev_mapping_clear(rbd_dev);
5337 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
5339 while (rbd_dev->parent) {
5340 struct rbd_device *first = rbd_dev;
5341 struct rbd_device *second = first->parent;
5342 struct rbd_device *third;
5345 * Follow to the parent with no grandparent and
5348 while (second && (third = second->parent)) {
5353 rbd_dev_image_release(second);
5354 first->parent = NULL;
5355 first->parent_overlap = 0;
5357 rbd_assert(first->parent_spec);
5358 rbd_spec_put(first->parent_spec);
5359 first->parent_spec = NULL;
5363 static ssize_t do_rbd_remove(struct bus_type *bus,
5367 struct rbd_device *rbd_dev = NULL;
5368 struct list_head *tmp;
5371 bool already = false;
5374 ret = kstrtoul(buf, 10, &ul);
5378 /* convert to int; abort if we lost anything in the conversion */
5384 spin_lock(&rbd_dev_list_lock);
5385 list_for_each(tmp, &rbd_dev_list) {
5386 rbd_dev = list_entry(tmp, struct rbd_device, node);
5387 if (rbd_dev->dev_id == dev_id) {
5393 spin_lock_irq(&rbd_dev->lock);
5394 if (rbd_dev->open_count)
5397 already = test_and_set_bit(RBD_DEV_FLAG_REMOVING,
5399 spin_unlock_irq(&rbd_dev->lock);
5401 spin_unlock(&rbd_dev_list_lock);
5402 if (ret < 0 || already)
5405 rbd_dev_header_unwatch_sync(rbd_dev);
5407 * flush remaining watch callbacks - these must be complete
5408 * before the osd_client is shutdown
5410 dout("%s: flushing notifies", __func__);
5411 ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc);
5414 * Don't free anything from rbd_dev->disk until after all
5415 * notifies are completely processed. Otherwise
5416 * rbd_bus_del_dev() will race with rbd_watch_cb(), resulting
5417 * in a potential use after free of rbd_dev->disk or rbd_dev.
5419 rbd_bus_del_dev(rbd_dev);
5420 rbd_dev_image_release(rbd_dev);
5421 module_put(THIS_MODULE);
5426 static ssize_t rbd_remove(struct bus_type *bus,
5433 return do_rbd_remove(bus, buf, count);
5436 static ssize_t rbd_remove_single_major(struct bus_type *bus,
5440 return do_rbd_remove(bus, buf, count);
5444 * create control files in sysfs
5447 static int rbd_sysfs_init(void)
5451 ret = device_register(&rbd_root_dev);
5455 ret = bus_register(&rbd_bus_type);
5457 device_unregister(&rbd_root_dev);
5462 static void rbd_sysfs_cleanup(void)
5464 bus_unregister(&rbd_bus_type);
5465 device_unregister(&rbd_root_dev);
5468 static int rbd_slab_init(void)
5470 rbd_assert(!rbd_img_request_cache);
5471 rbd_img_request_cache = kmem_cache_create("rbd_img_request",
5472 sizeof (struct rbd_img_request),
5473 __alignof__(struct rbd_img_request),
5475 if (!rbd_img_request_cache)
5478 rbd_assert(!rbd_obj_request_cache);
5479 rbd_obj_request_cache = kmem_cache_create("rbd_obj_request",
5480 sizeof (struct rbd_obj_request),
5481 __alignof__(struct rbd_obj_request),
5483 if (!rbd_obj_request_cache)
5486 rbd_assert(!rbd_segment_name_cache);
5487 rbd_segment_name_cache = kmem_cache_create("rbd_segment_name",
5488 CEPH_MAX_OID_NAME_LEN + 1, 1, 0, NULL);
5489 if (rbd_segment_name_cache)
5492 if (rbd_obj_request_cache) {
5493 kmem_cache_destroy(rbd_obj_request_cache);
5494 rbd_obj_request_cache = NULL;
5497 kmem_cache_destroy(rbd_img_request_cache);
5498 rbd_img_request_cache = NULL;
5503 static void rbd_slab_exit(void)
5505 rbd_assert(rbd_segment_name_cache);
5506 kmem_cache_destroy(rbd_segment_name_cache);
5507 rbd_segment_name_cache = NULL;
5509 rbd_assert(rbd_obj_request_cache);
5510 kmem_cache_destroy(rbd_obj_request_cache);
5511 rbd_obj_request_cache = NULL;
5513 rbd_assert(rbd_img_request_cache);
5514 kmem_cache_destroy(rbd_img_request_cache);
5515 rbd_img_request_cache = NULL;
5518 static int __init rbd_init(void)
5522 if (!libceph_compatible(NULL)) {
5523 rbd_warn(NULL, "libceph incompatibility (quitting)");
5527 rc = rbd_slab_init();
5532 rbd_major = register_blkdev(0, RBD_DRV_NAME);
5533 if (rbd_major < 0) {
5539 rc = rbd_sysfs_init();
5541 goto err_out_blkdev;
5544 pr_info("loaded (major %d)\n", rbd_major);
5546 pr_info("loaded\n");
5552 unregister_blkdev(rbd_major, RBD_DRV_NAME);
5558 static void __exit rbd_exit(void)
5560 ida_destroy(&rbd_dev_id_ida);
5561 rbd_sysfs_cleanup();
5563 unregister_blkdev(rbd_major, RBD_DRV_NAME);
5567 module_init(rbd_init);
5568 module_exit(rbd_exit);
5570 MODULE_AUTHOR("Alex Elder <elder@inktank.com>");
5571 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
5572 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
5573 /* following authorship retained from original osdblk.c */
5574 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
5576 MODULE_DESCRIPTION("RADOS Block Device (RBD) driver");
5577 MODULE_LICENSE("GPL");