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>
41 #include <linux/blk-mq.h>
43 #include <linux/blkdev.h>
44 #include <linux/slab.h>
45 #include <linux/idr.h>
46 #include <linux/workqueue.h>
48 #include "rbd_types.h"
50 #define RBD_DEBUG /* Activate rbd_assert() calls */
53 * The basic unit of block I/O is a sector. It is interpreted in a
54 * number of contexts in Linux (blk, bio, genhd), but the default is
55 * universally 512 bytes. These symbols are just slightly more
56 * meaningful than the bare numbers they represent.
58 #define SECTOR_SHIFT 9
59 #define SECTOR_SIZE (1ULL << SECTOR_SHIFT)
62 * Increment the given counter and return its updated value.
63 * If the counter is already 0 it will not be incremented.
64 * If the counter is already at its maximum value returns
65 * -EINVAL without updating it.
67 static int atomic_inc_return_safe(atomic_t *v)
71 counter = (unsigned int)__atomic_add_unless(v, 1, 0);
72 if (counter <= (unsigned int)INT_MAX)
80 /* Decrement the counter. Return the resulting value, or -EINVAL */
81 static int atomic_dec_return_safe(atomic_t *v)
85 counter = atomic_dec_return(v);
94 #define RBD_DRV_NAME "rbd"
96 #define RBD_MINORS_PER_MAJOR 256
97 #define RBD_SINGLE_MAJOR_PART_SHIFT 4
99 #define RBD_SNAP_DEV_NAME_PREFIX "snap_"
100 #define RBD_MAX_SNAP_NAME_LEN \
101 (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1))
103 #define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */
105 #define RBD_SNAP_HEAD_NAME "-"
107 #define BAD_SNAP_INDEX U32_MAX /* invalid index into snap array */
109 /* This allows a single page to hold an image name sent by OSD */
110 #define RBD_IMAGE_NAME_LEN_MAX (PAGE_SIZE - sizeof (__le32) - 1)
111 #define RBD_IMAGE_ID_LEN_MAX 64
113 #define RBD_OBJ_PREFIX_LEN_MAX 64
117 #define RBD_FEATURE_LAYERING (1<<0)
118 #define RBD_FEATURE_STRIPINGV2 (1<<1)
119 #define RBD_FEATURES_ALL \
120 (RBD_FEATURE_LAYERING | RBD_FEATURE_STRIPINGV2)
122 /* Features supported by this (client software) implementation. */
124 #define RBD_FEATURES_SUPPORTED (RBD_FEATURES_ALL)
127 * An RBD device name will be "rbd#", where the "rbd" comes from
128 * RBD_DRV_NAME above, and # is a unique integer identifier.
129 * MAX_INT_FORMAT_WIDTH is used in ensuring DEV_NAME_LEN is big
130 * enough to hold all possible device names.
132 #define DEV_NAME_LEN 32
133 #define MAX_INT_FORMAT_WIDTH ((5 * sizeof (int)) / 2 + 1)
136 * block device image metadata (in-memory version)
138 struct rbd_image_header {
139 /* These six fields never change for a given rbd image */
146 u64 features; /* Might be changeable someday? */
148 /* The remaining fields need to be updated occasionally */
150 struct ceph_snap_context *snapc;
151 char *snap_names; /* format 1 only */
152 u64 *snap_sizes; /* format 1 only */
156 * An rbd image specification.
158 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely
159 * identify an image. Each rbd_dev structure includes a pointer to
160 * an rbd_spec structure that encapsulates this identity.
162 * Each of the id's in an rbd_spec has an associated name. For a
163 * user-mapped image, the names are supplied and the id's associated
164 * with them are looked up. For a layered image, a parent image is
165 * defined by the tuple, and the names are looked up.
167 * An rbd_dev structure contains a parent_spec pointer which is
168 * non-null if the image it represents is a child in a layered
169 * image. This pointer will refer to the rbd_spec structure used
170 * by the parent rbd_dev for its own identity (i.e., the structure
171 * is shared between the parent and child).
173 * Since these structures are populated once, during the discovery
174 * phase of image construction, they are effectively immutable so
175 * we make no effort to synchronize access to them.
177 * Note that code herein does not assume the image name is known (it
178 * could be a null pointer).
182 const char *pool_name;
184 const char *image_id;
185 const char *image_name;
188 const char *snap_name;
194 * an instance of the client. multiple devices may share an rbd client.
197 struct ceph_client *client;
199 struct list_head node;
202 struct rbd_img_request;
203 typedef void (*rbd_img_callback_t)(struct rbd_img_request *);
205 #define BAD_WHICH U32_MAX /* Good which or bad which, which? */
207 struct rbd_obj_request;
208 typedef void (*rbd_obj_callback_t)(struct rbd_obj_request *);
210 enum obj_request_type {
211 OBJ_REQUEST_NODATA, OBJ_REQUEST_BIO, OBJ_REQUEST_PAGES
214 enum obj_operation_type {
221 OBJ_REQ_DONE, /* completion flag: not done = 0, done = 1 */
222 OBJ_REQ_IMG_DATA, /* object usage: standalone = 0, image = 1 */
223 OBJ_REQ_KNOWN, /* EXISTS flag valid: no = 0, yes = 1 */
224 OBJ_REQ_EXISTS, /* target exists: no = 0, yes = 1 */
227 struct rbd_obj_request {
228 const char *object_name;
229 u64 offset; /* object start byte */
230 u64 length; /* bytes from offset */
234 * An object request associated with an image will have its
235 * img_data flag set; a standalone object request will not.
237 * A standalone object request will have which == BAD_WHICH
238 * and a null obj_request pointer.
240 * An object request initiated in support of a layered image
241 * object (to check for its existence before a write) will
242 * have which == BAD_WHICH and a non-null obj_request pointer.
244 * Finally, an object request for rbd image data will have
245 * which != BAD_WHICH, and will have a non-null img_request
246 * pointer. The value of which will be in the range
247 * 0..(img_request->obj_request_count-1).
250 struct rbd_obj_request *obj_request; /* STAT op */
252 struct rbd_img_request *img_request;
254 /* links for img_request->obj_requests list */
255 struct list_head links;
258 u32 which; /* posn image request list */
260 enum obj_request_type type;
262 struct bio *bio_list;
268 struct page **copyup_pages;
269 u32 copyup_page_count;
271 struct ceph_osd_request *osd_req;
273 u64 xferred; /* bytes transferred */
276 rbd_obj_callback_t callback;
277 struct completion completion;
283 IMG_REQ_WRITE, /* I/O direction: read = 0, write = 1 */
284 IMG_REQ_CHILD, /* initiator: block = 0, child image = 1 */
285 IMG_REQ_LAYERED, /* ENOENT handling: normal = 0, layered = 1 */
286 IMG_REQ_DISCARD, /* discard: normal = 0, discard request = 1 */
289 struct rbd_img_request {
290 struct rbd_device *rbd_dev;
291 u64 offset; /* starting image byte offset */
292 u64 length; /* byte count from offset */
295 u64 snap_id; /* for reads */
296 struct ceph_snap_context *snapc; /* for writes */
299 struct request *rq; /* block request */
300 struct rbd_obj_request *obj_request; /* obj req initiator */
302 struct page **copyup_pages;
303 u32 copyup_page_count;
304 spinlock_t completion_lock;/* protects next_completion */
306 rbd_img_callback_t callback;
307 u64 xferred;/* aggregate bytes transferred */
308 int result; /* first nonzero obj_request result */
310 u32 obj_request_count;
311 struct list_head obj_requests; /* rbd_obj_request structs */
316 #define for_each_obj_request(ireq, oreq) \
317 list_for_each_entry(oreq, &(ireq)->obj_requests, links)
318 #define for_each_obj_request_from(ireq, oreq) \
319 list_for_each_entry_from(oreq, &(ireq)->obj_requests, links)
320 #define for_each_obj_request_safe(ireq, oreq, n) \
321 list_for_each_entry_safe_reverse(oreq, n, &(ireq)->obj_requests, links)
333 int dev_id; /* blkdev unique id */
335 int major; /* blkdev assigned major */
337 struct gendisk *disk; /* blkdev's gendisk and rq */
339 u32 image_format; /* Either 1 or 2 */
340 struct rbd_client *rbd_client;
342 char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */
344 spinlock_t lock; /* queue, flags, open_count */
346 struct rbd_image_header header;
347 unsigned long flags; /* possibly lock protected */
348 struct rbd_spec *spec;
349 struct rbd_options *opts;
353 struct ceph_file_layout layout;
355 struct ceph_osd_event *watch_event;
356 struct rbd_obj_request *watch_request;
358 struct rbd_spec *parent_spec;
361 struct rbd_device *parent;
363 /* Block layer tags. */
364 struct blk_mq_tag_set tag_set;
366 /* protects updating the header */
367 struct rw_semaphore header_rwsem;
369 struct rbd_mapping mapping;
371 struct list_head node;
375 unsigned long open_count; /* protected by lock */
379 * Flag bits for rbd_dev->flags. If atomicity is required,
380 * rbd_dev->lock is used to protect access.
382 * Currently, only the "removing" flag (which is coupled with the
383 * "open_count" field) requires atomic access.
386 RBD_DEV_FLAG_EXISTS, /* mapped snapshot has not been deleted */
387 RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */
390 static DEFINE_MUTEX(client_mutex); /* Serialize client creation */
392 static LIST_HEAD(rbd_dev_list); /* devices */
393 static DEFINE_SPINLOCK(rbd_dev_list_lock);
395 static LIST_HEAD(rbd_client_list); /* clients */
396 static DEFINE_SPINLOCK(rbd_client_list_lock);
398 /* Slab caches for frequently-allocated structures */
400 static struct kmem_cache *rbd_img_request_cache;
401 static struct kmem_cache *rbd_obj_request_cache;
402 static struct kmem_cache *rbd_segment_name_cache;
404 static int rbd_major;
405 static DEFINE_IDA(rbd_dev_id_ida);
407 static struct workqueue_struct *rbd_wq;
410 * Default to false for now, as single-major requires >= 0.75 version of
411 * userspace rbd utility.
413 static bool single_major = false;
414 module_param(single_major, bool, S_IRUGO);
415 MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: false)");
417 static int rbd_img_request_submit(struct rbd_img_request *img_request);
419 static void rbd_dev_device_release(struct device *dev);
421 static ssize_t rbd_add(struct bus_type *bus, const char *buf,
423 static ssize_t rbd_remove(struct bus_type *bus, const char *buf,
425 static ssize_t rbd_add_single_major(struct bus_type *bus, const char *buf,
427 static ssize_t rbd_remove_single_major(struct bus_type *bus, const char *buf,
429 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping);
430 static void rbd_spec_put(struct rbd_spec *spec);
432 static int rbd_dev_id_to_minor(int dev_id)
434 return dev_id << RBD_SINGLE_MAJOR_PART_SHIFT;
437 static int minor_to_rbd_dev_id(int minor)
439 return minor >> RBD_SINGLE_MAJOR_PART_SHIFT;
442 static BUS_ATTR(add, S_IWUSR, NULL, rbd_add);
443 static BUS_ATTR(remove, S_IWUSR, NULL, rbd_remove);
444 static BUS_ATTR(add_single_major, S_IWUSR, NULL, rbd_add_single_major);
445 static BUS_ATTR(remove_single_major, S_IWUSR, NULL, rbd_remove_single_major);
447 static struct attribute *rbd_bus_attrs[] = {
449 &bus_attr_remove.attr,
450 &bus_attr_add_single_major.attr,
451 &bus_attr_remove_single_major.attr,
455 static umode_t rbd_bus_is_visible(struct kobject *kobj,
456 struct attribute *attr, int index)
459 (attr == &bus_attr_add_single_major.attr ||
460 attr == &bus_attr_remove_single_major.attr))
466 static const struct attribute_group rbd_bus_group = {
467 .attrs = rbd_bus_attrs,
468 .is_visible = rbd_bus_is_visible,
470 __ATTRIBUTE_GROUPS(rbd_bus);
472 static struct bus_type rbd_bus_type = {
474 .bus_groups = rbd_bus_groups,
477 static void rbd_root_dev_release(struct device *dev)
481 static struct device rbd_root_dev = {
483 .release = rbd_root_dev_release,
486 static __printf(2, 3)
487 void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...)
489 struct va_format vaf;
497 printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf);
498 else if (rbd_dev->disk)
499 printk(KERN_WARNING "%s: %s: %pV\n",
500 RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf);
501 else if (rbd_dev->spec && rbd_dev->spec->image_name)
502 printk(KERN_WARNING "%s: image %s: %pV\n",
503 RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf);
504 else if (rbd_dev->spec && rbd_dev->spec->image_id)
505 printk(KERN_WARNING "%s: id %s: %pV\n",
506 RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf);
508 printk(KERN_WARNING "%s: rbd_dev %p: %pV\n",
509 RBD_DRV_NAME, rbd_dev, &vaf);
514 #define rbd_assert(expr) \
515 if (unlikely(!(expr))) { \
516 printk(KERN_ERR "\nAssertion failure in %s() " \
518 "\trbd_assert(%s);\n\n", \
519 __func__, __LINE__, #expr); \
522 #else /* !RBD_DEBUG */
523 # define rbd_assert(expr) ((void) 0)
524 #endif /* !RBD_DEBUG */
526 static void rbd_osd_copyup_callback(struct rbd_obj_request *obj_request);
527 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request);
528 static void rbd_img_parent_read(struct rbd_obj_request *obj_request);
529 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev);
531 static int rbd_dev_refresh(struct rbd_device *rbd_dev);
532 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev);
533 static int rbd_dev_header_info(struct rbd_device *rbd_dev);
534 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev);
535 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
537 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
538 u8 *order, u64 *snap_size);
539 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
541 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name);
543 static int rbd_open(struct block_device *bdev, fmode_t mode)
545 struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
546 bool removing = false;
548 if ((mode & FMODE_WRITE) && rbd_dev->mapping.read_only)
551 spin_lock_irq(&rbd_dev->lock);
552 if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags))
555 rbd_dev->open_count++;
556 spin_unlock_irq(&rbd_dev->lock);
560 (void) get_device(&rbd_dev->dev);
565 static void rbd_release(struct gendisk *disk, fmode_t mode)
567 struct rbd_device *rbd_dev = disk->private_data;
568 unsigned long open_count_before;
570 spin_lock_irq(&rbd_dev->lock);
571 open_count_before = rbd_dev->open_count--;
572 spin_unlock_irq(&rbd_dev->lock);
573 rbd_assert(open_count_before > 0);
575 put_device(&rbd_dev->dev);
578 static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg)
583 bool ro_changed = false;
585 /* get_user() may sleep, so call it before taking rbd_dev->lock */
586 if (get_user(val, (int __user *)(arg)))
589 ro = val ? true : false;
590 /* Snapshot doesn't allow to write*/
591 if (rbd_dev->spec->snap_id != CEPH_NOSNAP && !ro)
594 spin_lock_irq(&rbd_dev->lock);
595 /* prevent others open this device */
596 if (rbd_dev->open_count > 1) {
601 if (rbd_dev->mapping.read_only != ro) {
602 rbd_dev->mapping.read_only = ro;
607 spin_unlock_irq(&rbd_dev->lock);
608 /* set_disk_ro() may sleep, so call it after releasing rbd_dev->lock */
609 if (ret == 0 && ro_changed)
610 set_disk_ro(rbd_dev->disk, ro ? 1 : 0);
615 static int rbd_ioctl(struct block_device *bdev, fmode_t mode,
616 unsigned int cmd, unsigned long arg)
618 struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
623 ret = rbd_ioctl_set_ro(rbd_dev, arg);
633 static int rbd_compat_ioctl(struct block_device *bdev, fmode_t mode,
634 unsigned int cmd, unsigned long arg)
636 return rbd_ioctl(bdev, mode, cmd, arg);
638 #endif /* CONFIG_COMPAT */
640 static const struct block_device_operations rbd_bd_ops = {
641 .owner = THIS_MODULE,
643 .release = rbd_release,
646 .compat_ioctl = rbd_compat_ioctl,
651 * Initialize an rbd client instance. Success or not, this function
652 * consumes ceph_opts. Caller holds client_mutex.
654 static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
656 struct rbd_client *rbdc;
659 dout("%s:\n", __func__);
660 rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
664 kref_init(&rbdc->kref);
665 INIT_LIST_HEAD(&rbdc->node);
667 rbdc->client = ceph_create_client(ceph_opts, rbdc, 0, 0);
668 if (IS_ERR(rbdc->client))
670 ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
672 ret = ceph_open_session(rbdc->client);
676 spin_lock(&rbd_client_list_lock);
677 list_add_tail(&rbdc->node, &rbd_client_list);
678 spin_unlock(&rbd_client_list_lock);
680 dout("%s: rbdc %p\n", __func__, rbdc);
684 ceph_destroy_client(rbdc->client);
689 ceph_destroy_options(ceph_opts);
690 dout("%s: error %d\n", __func__, ret);
695 static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
697 kref_get(&rbdc->kref);
703 * Find a ceph client with specific addr and configuration. If
704 * found, bump its reference count.
706 static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
708 struct rbd_client *client_node;
711 if (ceph_opts->flags & CEPH_OPT_NOSHARE)
714 spin_lock(&rbd_client_list_lock);
715 list_for_each_entry(client_node, &rbd_client_list, node) {
716 if (!ceph_compare_options(ceph_opts, client_node->client)) {
717 __rbd_get_client(client_node);
723 spin_unlock(&rbd_client_list_lock);
725 return found ? client_node : NULL;
729 * (Per device) rbd map options
736 /* string args above */
742 static match_table_t rbd_opts_tokens = {
743 {Opt_queue_depth, "queue_depth=%d"},
745 /* string args above */
746 {Opt_read_only, "read_only"},
747 {Opt_read_only, "ro"}, /* Alternate spelling */
748 {Opt_read_write, "read_write"},
749 {Opt_read_write, "rw"}, /* Alternate spelling */
758 #define RBD_QUEUE_DEPTH_DEFAULT BLKDEV_MAX_RQ
759 #define RBD_READ_ONLY_DEFAULT false
761 static int parse_rbd_opts_token(char *c, void *private)
763 struct rbd_options *rbd_opts = private;
764 substring_t argstr[MAX_OPT_ARGS];
765 int token, intval, ret;
767 token = match_token(c, rbd_opts_tokens, argstr);
768 if (token < Opt_last_int) {
769 ret = match_int(&argstr[0], &intval);
771 pr_err("bad mount option arg (not int) at '%s'\n", c);
774 dout("got int token %d val %d\n", token, intval);
775 } else if (token > Opt_last_int && token < Opt_last_string) {
776 dout("got string token %d val %s\n", token, argstr[0].from);
778 dout("got token %d\n", token);
782 case Opt_queue_depth:
784 pr_err("queue_depth out of range\n");
787 rbd_opts->queue_depth = intval;
790 rbd_opts->read_only = true;
793 rbd_opts->read_only = false;
796 /* libceph prints "bad option" msg */
803 static char* obj_op_name(enum obj_operation_type op_type)
818 * Get a ceph client with specific addr and configuration, if one does
819 * not exist create it. Either way, ceph_opts is consumed by this
822 static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
824 struct rbd_client *rbdc;
826 mutex_lock_nested(&client_mutex, SINGLE_DEPTH_NESTING);
827 rbdc = rbd_client_find(ceph_opts);
828 if (rbdc) /* using an existing client */
829 ceph_destroy_options(ceph_opts);
831 rbdc = rbd_client_create(ceph_opts);
832 mutex_unlock(&client_mutex);
838 * Destroy ceph client
840 * Caller must hold rbd_client_list_lock.
842 static void rbd_client_release(struct kref *kref)
844 struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);
846 dout("%s: rbdc %p\n", __func__, rbdc);
847 spin_lock(&rbd_client_list_lock);
848 list_del(&rbdc->node);
849 spin_unlock(&rbd_client_list_lock);
851 ceph_destroy_client(rbdc->client);
856 * Drop reference to ceph client node. If it's not referenced anymore, release
859 static void rbd_put_client(struct rbd_client *rbdc)
862 kref_put(&rbdc->kref, rbd_client_release);
865 static bool rbd_image_format_valid(u32 image_format)
867 return image_format == 1 || image_format == 2;
870 static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
875 /* The header has to start with the magic rbd header text */
876 if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
879 /* The bio layer requires at least sector-sized I/O */
881 if (ondisk->options.order < SECTOR_SHIFT)
884 /* If we use u64 in a few spots we may be able to loosen this */
886 if (ondisk->options.order > 8 * sizeof (int) - 1)
890 * The size of a snapshot header has to fit in a size_t, and
891 * that limits the number of snapshots.
893 snap_count = le32_to_cpu(ondisk->snap_count);
894 size = SIZE_MAX - sizeof (struct ceph_snap_context);
895 if (snap_count > size / sizeof (__le64))
899 * Not only that, but the size of the entire the snapshot
900 * header must also be representable in a size_t.
902 size -= snap_count * sizeof (__le64);
903 if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
910 * Fill an rbd image header with information from the given format 1
913 static int rbd_header_from_disk(struct rbd_device *rbd_dev,
914 struct rbd_image_header_ondisk *ondisk)
916 struct rbd_image_header *header = &rbd_dev->header;
917 bool first_time = header->object_prefix == NULL;
918 struct ceph_snap_context *snapc;
919 char *object_prefix = NULL;
920 char *snap_names = NULL;
921 u64 *snap_sizes = NULL;
927 /* Allocate this now to avoid having to handle failure below */
932 len = strnlen(ondisk->object_prefix,
933 sizeof (ondisk->object_prefix));
934 object_prefix = kmalloc(len + 1, GFP_KERNEL);
937 memcpy(object_prefix, ondisk->object_prefix, len);
938 object_prefix[len] = '\0';
941 /* Allocate the snapshot context and fill it in */
943 snap_count = le32_to_cpu(ondisk->snap_count);
944 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
947 snapc->seq = le64_to_cpu(ondisk->snap_seq);
949 struct rbd_image_snap_ondisk *snaps;
950 u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);
952 /* We'll keep a copy of the snapshot names... */
954 if (snap_names_len > (u64)SIZE_MAX)
956 snap_names = kmalloc(snap_names_len, GFP_KERNEL);
960 /* ...as well as the array of their sizes. */
962 size = snap_count * sizeof (*header->snap_sizes);
963 snap_sizes = kmalloc(size, GFP_KERNEL);
968 * Copy the names, and fill in each snapshot's id
971 * Note that rbd_dev_v1_header_info() guarantees the
972 * ondisk buffer we're working with has
973 * snap_names_len bytes beyond the end of the
974 * snapshot id array, this memcpy() is safe.
976 memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len);
977 snaps = ondisk->snaps;
978 for (i = 0; i < snap_count; i++) {
979 snapc->snaps[i] = le64_to_cpu(snaps[i].id);
980 snap_sizes[i] = le64_to_cpu(snaps[i].image_size);
984 /* We won't fail any more, fill in the header */
987 header->object_prefix = object_prefix;
988 header->obj_order = ondisk->options.order;
989 header->crypt_type = ondisk->options.crypt_type;
990 header->comp_type = ondisk->options.comp_type;
991 /* The rest aren't used for format 1 images */
992 header->stripe_unit = 0;
993 header->stripe_count = 0;
994 header->features = 0;
996 ceph_put_snap_context(header->snapc);
997 kfree(header->snap_names);
998 kfree(header->snap_sizes);
1001 /* The remaining fields always get updated (when we refresh) */
1003 header->image_size = le64_to_cpu(ondisk->image_size);
1004 header->snapc = snapc;
1005 header->snap_names = snap_names;
1006 header->snap_sizes = snap_sizes;
1014 ceph_put_snap_context(snapc);
1015 kfree(object_prefix);
1020 static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
1022 const char *snap_name;
1024 rbd_assert(which < rbd_dev->header.snapc->num_snaps);
1026 /* Skip over names until we find the one we are looking for */
1028 snap_name = rbd_dev->header.snap_names;
1030 snap_name += strlen(snap_name) + 1;
1032 return kstrdup(snap_name, GFP_KERNEL);
1036 * Snapshot id comparison function for use with qsort()/bsearch().
1037 * Note that result is for snapshots in *descending* order.
1039 static int snapid_compare_reverse(const void *s1, const void *s2)
1041 u64 snap_id1 = *(u64 *)s1;
1042 u64 snap_id2 = *(u64 *)s2;
1044 if (snap_id1 < snap_id2)
1046 return snap_id1 == snap_id2 ? 0 : -1;
1050 * Search a snapshot context to see if the given snapshot id is
1053 * Returns the position of the snapshot id in the array if it's found,
1054 * or BAD_SNAP_INDEX otherwise.
1056 * Note: The snapshot array is in kept sorted (by the osd) in
1057 * reverse order, highest snapshot id first.
1059 static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id)
1061 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
1064 found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps,
1065 sizeof (snap_id), snapid_compare_reverse);
1067 return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX;
1070 static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
1074 const char *snap_name;
1076 which = rbd_dev_snap_index(rbd_dev, snap_id);
1077 if (which == BAD_SNAP_INDEX)
1078 return ERR_PTR(-ENOENT);
1080 snap_name = _rbd_dev_v1_snap_name(rbd_dev, which);
1081 return snap_name ? snap_name : ERR_PTR(-ENOMEM);
1084 static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
1086 if (snap_id == CEPH_NOSNAP)
1087 return RBD_SNAP_HEAD_NAME;
1089 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1090 if (rbd_dev->image_format == 1)
1091 return rbd_dev_v1_snap_name(rbd_dev, snap_id);
1093 return rbd_dev_v2_snap_name(rbd_dev, snap_id);
1096 static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
1099 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1100 if (snap_id == CEPH_NOSNAP) {
1101 *snap_size = rbd_dev->header.image_size;
1102 } else if (rbd_dev->image_format == 1) {
1105 which = rbd_dev_snap_index(rbd_dev, snap_id);
1106 if (which == BAD_SNAP_INDEX)
1109 *snap_size = rbd_dev->header.snap_sizes[which];
1114 ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
1123 static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
1126 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
1127 if (snap_id == CEPH_NOSNAP) {
1128 *snap_features = rbd_dev->header.features;
1129 } else if (rbd_dev->image_format == 1) {
1130 *snap_features = 0; /* No features for format 1 */
1135 ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features);
1139 *snap_features = features;
1144 static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
1146 u64 snap_id = rbd_dev->spec->snap_id;
1151 ret = rbd_snap_size(rbd_dev, snap_id, &size);
1154 ret = rbd_snap_features(rbd_dev, snap_id, &features);
1158 rbd_dev->mapping.size = size;
1159 rbd_dev->mapping.features = features;
1164 static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
1166 rbd_dev->mapping.size = 0;
1167 rbd_dev->mapping.features = 0;
1170 static void rbd_segment_name_free(const char *name)
1172 /* The explicit cast here is needed to drop the const qualifier */
1174 kmem_cache_free(rbd_segment_name_cache, (void *)name);
1177 static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset)
1184 name = kmem_cache_alloc(rbd_segment_name_cache, GFP_NOIO);
1187 segment = offset >> rbd_dev->header.obj_order;
1188 name_format = "%s.%012llx";
1189 if (rbd_dev->image_format == 2)
1190 name_format = "%s.%016llx";
1191 ret = snprintf(name, CEPH_MAX_OID_NAME_LEN + 1, name_format,
1192 rbd_dev->header.object_prefix, segment);
1193 if (ret < 0 || ret > CEPH_MAX_OID_NAME_LEN) {
1194 pr_err("error formatting segment name for #%llu (%d)\n",
1196 rbd_segment_name_free(name);
1203 static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset)
1205 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1207 return offset & (segment_size - 1);
1210 static u64 rbd_segment_length(struct rbd_device *rbd_dev,
1211 u64 offset, u64 length)
1213 u64 segment_size = (u64) 1 << rbd_dev->header.obj_order;
1215 offset &= segment_size - 1;
1217 rbd_assert(length <= U64_MAX - offset);
1218 if (offset + length > segment_size)
1219 length = segment_size - offset;
1225 * returns the size of an object in the image
1227 static u64 rbd_obj_bytes(struct rbd_image_header *header)
1229 return 1 << header->obj_order;
1236 static void bio_chain_put(struct bio *chain)
1242 chain = chain->bi_next;
1248 * zeros a bio chain, starting at specific offset
1250 static void zero_bio_chain(struct bio *chain, int start_ofs)
1253 struct bvec_iter iter;
1254 unsigned long flags;
1259 bio_for_each_segment(bv, chain, iter) {
1260 if (pos + bv.bv_len > start_ofs) {
1261 int remainder = max(start_ofs - pos, 0);
1262 buf = bvec_kmap_irq(&bv, &flags);
1263 memset(buf + remainder, 0,
1264 bv.bv_len - remainder);
1265 flush_dcache_page(bv.bv_page);
1266 bvec_kunmap_irq(buf, &flags);
1271 chain = chain->bi_next;
1276 * similar to zero_bio_chain(), zeros data defined by a page array,
1277 * starting at the given byte offset from the start of the array and
1278 * continuing up to the given end offset. The pages array is
1279 * assumed to be big enough to hold all bytes up to the end.
1281 static void zero_pages(struct page **pages, u64 offset, u64 end)
1283 struct page **page = &pages[offset >> PAGE_SHIFT];
1285 rbd_assert(end > offset);
1286 rbd_assert(end - offset <= (u64)SIZE_MAX);
1287 while (offset < end) {
1290 unsigned long flags;
1293 page_offset = offset & ~PAGE_MASK;
1294 length = min_t(size_t, PAGE_SIZE - page_offset, end - offset);
1295 local_irq_save(flags);
1296 kaddr = kmap_atomic(*page);
1297 memset(kaddr + page_offset, 0, length);
1298 flush_dcache_page(*page);
1299 kunmap_atomic(kaddr);
1300 local_irq_restore(flags);
1308 * Clone a portion of a bio, starting at the given byte offset
1309 * and continuing for the number of bytes indicated.
1311 static struct bio *bio_clone_range(struct bio *bio_src,
1312 unsigned int offset,
1318 bio = bio_clone(bio_src, gfpmask);
1320 return NULL; /* ENOMEM */
1322 bio_advance(bio, offset);
1323 bio->bi_iter.bi_size = len;
1329 * Clone a portion of a bio chain, starting at the given byte offset
1330 * into the first bio in the source chain and continuing for the
1331 * number of bytes indicated. The result is another bio chain of
1332 * exactly the given length, or a null pointer on error.
1334 * The bio_src and offset parameters are both in-out. On entry they
1335 * refer to the first source bio and the offset into that bio where
1336 * the start of data to be cloned is located.
1338 * On return, bio_src is updated to refer to the bio in the source
1339 * chain that contains first un-cloned byte, and *offset will
1340 * contain the offset of that byte within that bio.
1342 static struct bio *bio_chain_clone_range(struct bio **bio_src,
1343 unsigned int *offset,
1347 struct bio *bi = *bio_src;
1348 unsigned int off = *offset;
1349 struct bio *chain = NULL;
1352 /* Build up a chain of clone bios up to the limit */
1354 if (!bi || off >= bi->bi_iter.bi_size || !len)
1355 return NULL; /* Nothing to clone */
1359 unsigned int bi_size;
1363 rbd_warn(NULL, "bio_chain exhausted with %u left", len);
1364 goto out_err; /* EINVAL; ran out of bio's */
1366 bi_size = min_t(unsigned int, bi->bi_iter.bi_size - off, len);
1367 bio = bio_clone_range(bi, off, bi_size, gfpmask);
1369 goto out_err; /* ENOMEM */
1372 end = &bio->bi_next;
1375 if (off == bi->bi_iter.bi_size) {
1386 bio_chain_put(chain);
1392 * The default/initial value for all object request flags is 0. For
1393 * each flag, once its value is set to 1 it is never reset to 0
1396 static void obj_request_img_data_set(struct rbd_obj_request *obj_request)
1398 if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) {
1399 struct rbd_device *rbd_dev;
1401 rbd_dev = obj_request->img_request->rbd_dev;
1402 rbd_warn(rbd_dev, "obj_request %p already marked img_data",
1407 static bool obj_request_img_data_test(struct rbd_obj_request *obj_request)
1410 return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0;
1413 static void obj_request_done_set(struct rbd_obj_request *obj_request)
1415 if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) {
1416 struct rbd_device *rbd_dev = NULL;
1418 if (obj_request_img_data_test(obj_request))
1419 rbd_dev = obj_request->img_request->rbd_dev;
1420 rbd_warn(rbd_dev, "obj_request %p already marked done",
1425 static bool obj_request_done_test(struct rbd_obj_request *obj_request)
1428 return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0;
1432 * This sets the KNOWN flag after (possibly) setting the EXISTS
1433 * flag. The latter is set based on the "exists" value provided.
1435 * Note that for our purposes once an object exists it never goes
1436 * away again. It's possible that the response from two existence
1437 * checks are separated by the creation of the target object, and
1438 * the first ("doesn't exist") response arrives *after* the second
1439 * ("does exist"). In that case we ignore the second one.
1441 static void obj_request_existence_set(struct rbd_obj_request *obj_request,
1445 set_bit(OBJ_REQ_EXISTS, &obj_request->flags);
1446 set_bit(OBJ_REQ_KNOWN, &obj_request->flags);
1450 static bool obj_request_known_test(struct rbd_obj_request *obj_request)
1453 return test_bit(OBJ_REQ_KNOWN, &obj_request->flags) != 0;
1456 static bool obj_request_exists_test(struct rbd_obj_request *obj_request)
1459 return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0;
1462 static bool obj_request_overlaps_parent(struct rbd_obj_request *obj_request)
1464 struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev;
1466 return obj_request->img_offset <
1467 round_up(rbd_dev->parent_overlap, rbd_obj_bytes(&rbd_dev->header));
1470 static void rbd_obj_request_get(struct rbd_obj_request *obj_request)
1472 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1473 atomic_read(&obj_request->kref.refcount));
1474 kref_get(&obj_request->kref);
1477 static void rbd_obj_request_destroy(struct kref *kref);
1478 static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
1480 rbd_assert(obj_request != NULL);
1481 dout("%s: obj %p (was %d)\n", __func__, obj_request,
1482 atomic_read(&obj_request->kref.refcount));
1483 kref_put(&obj_request->kref, rbd_obj_request_destroy);
1486 static void rbd_img_request_get(struct rbd_img_request *img_request)
1488 dout("%s: img %p (was %d)\n", __func__, img_request,
1489 atomic_read(&img_request->kref.refcount));
1490 kref_get(&img_request->kref);
1493 static bool img_request_child_test(struct rbd_img_request *img_request);
1494 static void rbd_parent_request_destroy(struct kref *kref);
1495 static void rbd_img_request_destroy(struct kref *kref);
1496 static void rbd_img_request_put(struct rbd_img_request *img_request)
1498 rbd_assert(img_request != NULL);
1499 dout("%s: img %p (was %d)\n", __func__, img_request,
1500 atomic_read(&img_request->kref.refcount));
1501 if (img_request_child_test(img_request))
1502 kref_put(&img_request->kref, rbd_parent_request_destroy);
1504 kref_put(&img_request->kref, rbd_img_request_destroy);
1507 static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
1508 struct rbd_obj_request *obj_request)
1510 rbd_assert(obj_request->img_request == NULL);
1512 /* Image request now owns object's original reference */
1513 obj_request->img_request = img_request;
1514 obj_request->which = img_request->obj_request_count;
1515 rbd_assert(!obj_request_img_data_test(obj_request));
1516 obj_request_img_data_set(obj_request);
1517 rbd_assert(obj_request->which != BAD_WHICH);
1518 img_request->obj_request_count++;
1519 list_add_tail(&obj_request->links, &img_request->obj_requests);
1520 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1521 obj_request->which);
1524 static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
1525 struct rbd_obj_request *obj_request)
1527 rbd_assert(obj_request->which != BAD_WHICH);
1529 dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
1530 obj_request->which);
1531 list_del(&obj_request->links);
1532 rbd_assert(img_request->obj_request_count > 0);
1533 img_request->obj_request_count--;
1534 rbd_assert(obj_request->which == img_request->obj_request_count);
1535 obj_request->which = BAD_WHICH;
1536 rbd_assert(obj_request_img_data_test(obj_request));
1537 rbd_assert(obj_request->img_request == img_request);
1538 obj_request->img_request = NULL;
1539 obj_request->callback = NULL;
1540 rbd_obj_request_put(obj_request);
1543 static bool obj_request_type_valid(enum obj_request_type type)
1546 case OBJ_REQUEST_NODATA:
1547 case OBJ_REQUEST_BIO:
1548 case OBJ_REQUEST_PAGES:
1555 static int rbd_obj_request_submit(struct ceph_osd_client *osdc,
1556 struct rbd_obj_request *obj_request)
1558 dout("%s %p\n", __func__, obj_request);
1559 return ceph_osdc_start_request(osdc, obj_request->osd_req, false);
1562 static void rbd_obj_request_end(struct rbd_obj_request *obj_request)
1564 dout("%s %p\n", __func__, obj_request);
1565 ceph_osdc_cancel_request(obj_request->osd_req);
1569 * Wait for an object request to complete. If interrupted, cancel the
1570 * underlying osd request.
1572 * @timeout: in jiffies, 0 means "wait forever"
1574 static int __rbd_obj_request_wait(struct rbd_obj_request *obj_request,
1575 unsigned long timeout)
1579 dout("%s %p\n", __func__, obj_request);
1580 ret = wait_for_completion_interruptible_timeout(
1581 &obj_request->completion,
1582 ceph_timeout_jiffies(timeout));
1586 rbd_obj_request_end(obj_request);
1591 dout("%s %p ret %d\n", __func__, obj_request, (int)ret);
1595 static int rbd_obj_request_wait(struct rbd_obj_request *obj_request)
1597 return __rbd_obj_request_wait(obj_request, 0);
1600 static int rbd_obj_request_wait_timeout(struct rbd_obj_request *obj_request,
1601 unsigned long timeout)
1603 return __rbd_obj_request_wait(obj_request, timeout);
1606 static void rbd_img_request_complete(struct rbd_img_request *img_request)
1609 dout("%s: img %p\n", __func__, img_request);
1612 * If no error occurred, compute the aggregate transfer
1613 * count for the image request. We could instead use
1614 * atomic64_cmpxchg() to update it as each object request
1615 * completes; not clear which way is better off hand.
1617 if (!img_request->result) {
1618 struct rbd_obj_request *obj_request;
1621 for_each_obj_request(img_request, obj_request)
1622 xferred += obj_request->xferred;
1623 img_request->xferred = xferred;
1626 if (img_request->callback)
1627 img_request->callback(img_request);
1629 rbd_img_request_put(img_request);
1633 * The default/initial value for all image request flags is 0. Each
1634 * is conditionally set to 1 at image request initialization time
1635 * and currently never change thereafter.
1637 static void img_request_write_set(struct rbd_img_request *img_request)
1639 set_bit(IMG_REQ_WRITE, &img_request->flags);
1643 static bool img_request_write_test(struct rbd_img_request *img_request)
1646 return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0;
1650 * Set the discard flag when the img_request is an discard request
1652 static void img_request_discard_set(struct rbd_img_request *img_request)
1654 set_bit(IMG_REQ_DISCARD, &img_request->flags);
1658 static bool img_request_discard_test(struct rbd_img_request *img_request)
1661 return test_bit(IMG_REQ_DISCARD, &img_request->flags) != 0;
1664 static void img_request_child_set(struct rbd_img_request *img_request)
1666 set_bit(IMG_REQ_CHILD, &img_request->flags);
1670 static void img_request_child_clear(struct rbd_img_request *img_request)
1672 clear_bit(IMG_REQ_CHILD, &img_request->flags);
1676 static bool img_request_child_test(struct rbd_img_request *img_request)
1679 return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0;
1682 static void img_request_layered_set(struct rbd_img_request *img_request)
1684 set_bit(IMG_REQ_LAYERED, &img_request->flags);
1688 static void img_request_layered_clear(struct rbd_img_request *img_request)
1690 clear_bit(IMG_REQ_LAYERED, &img_request->flags);
1694 static bool img_request_layered_test(struct rbd_img_request *img_request)
1697 return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
1700 static enum obj_operation_type
1701 rbd_img_request_op_type(struct rbd_img_request *img_request)
1703 if (img_request_write_test(img_request))
1704 return OBJ_OP_WRITE;
1705 else if (img_request_discard_test(img_request))
1706 return OBJ_OP_DISCARD;
1712 rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
1714 u64 xferred = obj_request->xferred;
1715 u64 length = obj_request->length;
1717 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1718 obj_request, obj_request->img_request, obj_request->result,
1721 * ENOENT means a hole in the image. We zero-fill the entire
1722 * length of the request. A short read also implies zero-fill
1723 * to the end of the request. An error requires the whole
1724 * length of the request to be reported finished with an error
1725 * to the block layer. In each case we update the xferred
1726 * count to indicate the whole request was satisfied.
1728 rbd_assert(obj_request->type != OBJ_REQUEST_NODATA);
1729 if (obj_request->result == -ENOENT) {
1730 if (obj_request->type == OBJ_REQUEST_BIO)
1731 zero_bio_chain(obj_request->bio_list, 0);
1733 zero_pages(obj_request->pages, 0, length);
1734 obj_request->result = 0;
1735 } else if (xferred < length && !obj_request->result) {
1736 if (obj_request->type == OBJ_REQUEST_BIO)
1737 zero_bio_chain(obj_request->bio_list, xferred);
1739 zero_pages(obj_request->pages, xferred, length);
1741 obj_request->xferred = length;
1742 obj_request_done_set(obj_request);
1745 static void rbd_obj_request_complete(struct rbd_obj_request *obj_request)
1747 dout("%s: obj %p cb %p\n", __func__, obj_request,
1748 obj_request->callback);
1749 if (obj_request->callback)
1750 obj_request->callback(obj_request);
1752 complete_all(&obj_request->completion);
1755 static void rbd_osd_trivial_callback(struct rbd_obj_request *obj_request)
1757 dout("%s: obj %p\n", __func__, obj_request);
1758 obj_request_done_set(obj_request);
1761 static void rbd_osd_read_callback(struct rbd_obj_request *obj_request)
1763 struct rbd_img_request *img_request = NULL;
1764 struct rbd_device *rbd_dev = NULL;
1765 bool layered = false;
1767 if (obj_request_img_data_test(obj_request)) {
1768 img_request = obj_request->img_request;
1769 layered = img_request && img_request_layered_test(img_request);
1770 rbd_dev = img_request->rbd_dev;
1773 dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
1774 obj_request, img_request, obj_request->result,
1775 obj_request->xferred, obj_request->length);
1776 if (layered && obj_request->result == -ENOENT &&
1777 obj_request->img_offset < rbd_dev->parent_overlap)
1778 rbd_img_parent_read(obj_request);
1779 else if (img_request)
1780 rbd_img_obj_request_read_callback(obj_request);
1782 obj_request_done_set(obj_request);
1785 static void rbd_osd_write_callback(struct rbd_obj_request *obj_request)
1787 dout("%s: obj %p result %d %llu\n", __func__, obj_request,
1788 obj_request->result, obj_request->length);
1790 * There is no such thing as a successful short write. Set
1791 * it to our originally-requested length.
1793 obj_request->xferred = obj_request->length;
1794 obj_request_done_set(obj_request);
1797 static void rbd_osd_discard_callback(struct rbd_obj_request *obj_request)
1799 dout("%s: obj %p result %d %llu\n", __func__, obj_request,
1800 obj_request->result, obj_request->length);
1802 * There is no such thing as a successful short discard. Set
1803 * it to our originally-requested length.
1805 obj_request->xferred = obj_request->length;
1806 /* discarding a non-existent object is not a problem */
1807 if (obj_request->result == -ENOENT)
1808 obj_request->result = 0;
1809 obj_request_done_set(obj_request);
1813 * For a simple stat call there's nothing to do. We'll do more if
1814 * this is part of a write sequence for a layered image.
1816 static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request)
1818 dout("%s: obj %p\n", __func__, obj_request);
1819 obj_request_done_set(obj_request);
1822 static void rbd_osd_call_callback(struct rbd_obj_request *obj_request)
1824 dout("%s: obj %p\n", __func__, obj_request);
1826 if (obj_request_img_data_test(obj_request))
1827 rbd_osd_copyup_callback(obj_request);
1829 obj_request_done_set(obj_request);
1832 static void rbd_osd_req_callback(struct ceph_osd_request *osd_req,
1833 struct ceph_msg *msg)
1835 struct rbd_obj_request *obj_request = osd_req->r_priv;
1838 dout("%s: osd_req %p msg %p\n", __func__, osd_req, msg);
1839 rbd_assert(osd_req == obj_request->osd_req);
1840 if (obj_request_img_data_test(obj_request)) {
1841 rbd_assert(obj_request->img_request);
1842 rbd_assert(obj_request->which != BAD_WHICH);
1844 rbd_assert(obj_request->which == BAD_WHICH);
1847 if (osd_req->r_result < 0)
1848 obj_request->result = osd_req->r_result;
1850 rbd_assert(osd_req->r_num_ops <= CEPH_OSD_MAX_OP);
1853 * We support a 64-bit length, but ultimately it has to be
1854 * passed to the block layer, which just supports a 32-bit
1857 obj_request->xferred = osd_req->r_reply_op_len[0];
1858 rbd_assert(obj_request->xferred < (u64)UINT_MAX);
1860 opcode = osd_req->r_ops[0].op;
1862 case CEPH_OSD_OP_READ:
1863 rbd_osd_read_callback(obj_request);
1865 case CEPH_OSD_OP_SETALLOCHINT:
1866 rbd_assert(osd_req->r_ops[1].op == CEPH_OSD_OP_WRITE);
1868 case CEPH_OSD_OP_WRITE:
1869 rbd_osd_write_callback(obj_request);
1871 case CEPH_OSD_OP_STAT:
1872 rbd_osd_stat_callback(obj_request);
1874 case CEPH_OSD_OP_DELETE:
1875 case CEPH_OSD_OP_TRUNCATE:
1876 case CEPH_OSD_OP_ZERO:
1877 rbd_osd_discard_callback(obj_request);
1879 case CEPH_OSD_OP_CALL:
1880 rbd_osd_call_callback(obj_request);
1882 case CEPH_OSD_OP_NOTIFY_ACK:
1883 case CEPH_OSD_OP_WATCH:
1884 rbd_osd_trivial_callback(obj_request);
1887 rbd_warn(NULL, "%s: unsupported op %hu",
1888 obj_request->object_name, (unsigned short) opcode);
1892 if (obj_request_done_test(obj_request))
1893 rbd_obj_request_complete(obj_request);
1896 static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request)
1898 struct rbd_img_request *img_request = obj_request->img_request;
1899 struct ceph_osd_request *osd_req = obj_request->osd_req;
1902 rbd_assert(osd_req != NULL);
1904 snap_id = img_request ? img_request->snap_id : CEPH_NOSNAP;
1905 ceph_osdc_build_request(osd_req, obj_request->offset,
1906 NULL, snap_id, NULL);
1909 static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request)
1911 struct rbd_img_request *img_request = obj_request->img_request;
1912 struct ceph_osd_request *osd_req = obj_request->osd_req;
1913 struct ceph_snap_context *snapc;
1914 struct timespec mtime = CURRENT_TIME;
1916 rbd_assert(osd_req != NULL);
1918 snapc = img_request ? img_request->snapc : NULL;
1919 ceph_osdc_build_request(osd_req, obj_request->offset,
1920 snapc, CEPH_NOSNAP, &mtime);
1924 * Create an osd request. A read request has one osd op (read).
1925 * A write request has either one (watch) or two (hint+write) osd ops.
1926 * (All rbd data writes are prefixed with an allocation hint op, but
1927 * technically osd watch is a write request, hence this distinction.)
1929 static struct ceph_osd_request *rbd_osd_req_create(
1930 struct rbd_device *rbd_dev,
1931 enum obj_operation_type op_type,
1932 unsigned int num_ops,
1933 struct rbd_obj_request *obj_request)
1935 struct ceph_snap_context *snapc = NULL;
1936 struct ceph_osd_client *osdc;
1937 struct ceph_osd_request *osd_req;
1939 if (obj_request_img_data_test(obj_request) &&
1940 (op_type == OBJ_OP_DISCARD || op_type == OBJ_OP_WRITE)) {
1941 struct rbd_img_request *img_request = obj_request->img_request;
1942 if (op_type == OBJ_OP_WRITE) {
1943 rbd_assert(img_request_write_test(img_request));
1945 rbd_assert(img_request_discard_test(img_request));
1947 snapc = img_request->snapc;
1950 rbd_assert(num_ops == 1 || ((op_type == OBJ_OP_WRITE) && num_ops == 2));
1952 /* Allocate and initialize the request, for the num_ops ops */
1954 osdc = &rbd_dev->rbd_client->client->osdc;
1955 osd_req = ceph_osdc_alloc_request(osdc, snapc, num_ops, false,
1958 return NULL; /* ENOMEM */
1960 if (op_type == OBJ_OP_WRITE || op_type == OBJ_OP_DISCARD)
1961 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
1963 osd_req->r_flags = CEPH_OSD_FLAG_READ;
1965 osd_req->r_callback = rbd_osd_req_callback;
1966 osd_req->r_priv = obj_request;
1968 osd_req->r_base_oloc.pool = ceph_file_layout_pg_pool(rbd_dev->layout);
1969 ceph_oid_set_name(&osd_req->r_base_oid, obj_request->object_name);
1975 * Create a copyup osd request based on the information in the object
1976 * request supplied. A copyup request has two or three osd ops, a
1977 * copyup method call, potentially a hint op, and a write or truncate
1980 static struct ceph_osd_request *
1981 rbd_osd_req_create_copyup(struct rbd_obj_request *obj_request)
1983 struct rbd_img_request *img_request;
1984 struct ceph_snap_context *snapc;
1985 struct rbd_device *rbd_dev;
1986 struct ceph_osd_client *osdc;
1987 struct ceph_osd_request *osd_req;
1988 int num_osd_ops = 3;
1990 rbd_assert(obj_request_img_data_test(obj_request));
1991 img_request = obj_request->img_request;
1992 rbd_assert(img_request);
1993 rbd_assert(img_request_write_test(img_request) ||
1994 img_request_discard_test(img_request));
1996 if (img_request_discard_test(img_request))
1999 /* Allocate and initialize the request, for all the ops */
2001 snapc = img_request->snapc;
2002 rbd_dev = img_request->rbd_dev;
2003 osdc = &rbd_dev->rbd_client->client->osdc;
2004 osd_req = ceph_osdc_alloc_request(osdc, snapc, num_osd_ops,
2007 return NULL; /* ENOMEM */
2009 osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK;
2010 osd_req->r_callback = rbd_osd_req_callback;
2011 osd_req->r_priv = obj_request;
2013 osd_req->r_base_oloc.pool = ceph_file_layout_pg_pool(rbd_dev->layout);
2014 ceph_oid_set_name(&osd_req->r_base_oid, obj_request->object_name);
2020 static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req)
2022 ceph_osdc_put_request(osd_req);
2025 /* object_name is assumed to be a non-null pointer and NUL-terminated */
2027 static struct rbd_obj_request *rbd_obj_request_create(const char *object_name,
2028 u64 offset, u64 length,
2029 enum obj_request_type type)
2031 struct rbd_obj_request *obj_request;
2035 rbd_assert(obj_request_type_valid(type));
2037 size = strlen(object_name) + 1;
2038 name = kmalloc(size, GFP_NOIO);
2042 obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_NOIO);
2048 obj_request->object_name = memcpy(name, object_name, size);
2049 obj_request->offset = offset;
2050 obj_request->length = length;
2051 obj_request->flags = 0;
2052 obj_request->which = BAD_WHICH;
2053 obj_request->type = type;
2054 INIT_LIST_HEAD(&obj_request->links);
2055 init_completion(&obj_request->completion);
2056 kref_init(&obj_request->kref);
2058 dout("%s: \"%s\" %llu/%llu %d -> obj %p\n", __func__, object_name,
2059 offset, length, (int)type, obj_request);
2064 static void rbd_obj_request_destroy(struct kref *kref)
2066 struct rbd_obj_request *obj_request;
2068 obj_request = container_of(kref, struct rbd_obj_request, kref);
2070 dout("%s: obj %p\n", __func__, obj_request);
2072 rbd_assert(obj_request->img_request == NULL);
2073 rbd_assert(obj_request->which == BAD_WHICH);
2075 if (obj_request->osd_req)
2076 rbd_osd_req_destroy(obj_request->osd_req);
2078 rbd_assert(obj_request_type_valid(obj_request->type));
2079 switch (obj_request->type) {
2080 case OBJ_REQUEST_NODATA:
2081 break; /* Nothing to do */
2082 case OBJ_REQUEST_BIO:
2083 if (obj_request->bio_list)
2084 bio_chain_put(obj_request->bio_list);
2086 case OBJ_REQUEST_PAGES:
2087 if (obj_request->pages)
2088 ceph_release_page_vector(obj_request->pages,
2089 obj_request->page_count);
2093 kfree(obj_request->object_name);
2094 obj_request->object_name = NULL;
2095 kmem_cache_free(rbd_obj_request_cache, obj_request);
2098 /* It's OK to call this for a device with no parent */
2100 static void rbd_spec_put(struct rbd_spec *spec);
2101 static void rbd_dev_unparent(struct rbd_device *rbd_dev)
2103 rbd_dev_remove_parent(rbd_dev);
2104 rbd_spec_put(rbd_dev->parent_spec);
2105 rbd_dev->parent_spec = NULL;
2106 rbd_dev->parent_overlap = 0;
2110 * Parent image reference counting is used to determine when an
2111 * image's parent fields can be safely torn down--after there are no
2112 * more in-flight requests to the parent image. When the last
2113 * reference is dropped, cleaning them up is safe.
2115 static void rbd_dev_parent_put(struct rbd_device *rbd_dev)
2119 if (!rbd_dev->parent_spec)
2122 counter = atomic_dec_return_safe(&rbd_dev->parent_ref);
2126 /* Last reference; clean up parent data structures */
2129 rbd_dev_unparent(rbd_dev);
2131 rbd_warn(rbd_dev, "parent reference underflow");
2135 * If an image has a non-zero parent overlap, get a reference to its
2138 * Returns true if the rbd device has a parent with a non-zero
2139 * overlap and a reference for it was successfully taken, or
2142 static bool rbd_dev_parent_get(struct rbd_device *rbd_dev)
2146 if (!rbd_dev->parent_spec)
2149 down_read(&rbd_dev->header_rwsem);
2150 if (rbd_dev->parent_overlap)
2151 counter = atomic_inc_return_safe(&rbd_dev->parent_ref);
2152 up_read(&rbd_dev->header_rwsem);
2155 rbd_warn(rbd_dev, "parent reference overflow");
2161 * Caller is responsible for filling in the list of object requests
2162 * that comprises the image request, and the Linux request pointer
2163 * (if there is one).
2165 static struct rbd_img_request *rbd_img_request_create(
2166 struct rbd_device *rbd_dev,
2167 u64 offset, u64 length,
2168 enum obj_operation_type op_type,
2169 struct ceph_snap_context *snapc)
2171 struct rbd_img_request *img_request;
2173 img_request = kmem_cache_alloc(rbd_img_request_cache, GFP_NOIO);
2177 img_request->rq = NULL;
2178 img_request->rbd_dev = rbd_dev;
2179 img_request->offset = offset;
2180 img_request->length = length;
2181 img_request->flags = 0;
2182 if (op_type == OBJ_OP_DISCARD) {
2183 img_request_discard_set(img_request);
2184 img_request->snapc = snapc;
2185 } else if (op_type == OBJ_OP_WRITE) {
2186 img_request_write_set(img_request);
2187 img_request->snapc = snapc;
2189 img_request->snap_id = rbd_dev->spec->snap_id;
2191 if (rbd_dev_parent_get(rbd_dev))
2192 img_request_layered_set(img_request);
2193 spin_lock_init(&img_request->completion_lock);
2194 img_request->next_completion = 0;
2195 img_request->callback = NULL;
2196 img_request->result = 0;
2197 img_request->obj_request_count = 0;
2198 INIT_LIST_HEAD(&img_request->obj_requests);
2199 kref_init(&img_request->kref);
2201 dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev,
2202 obj_op_name(op_type), offset, length, img_request);
2207 static void rbd_img_request_destroy(struct kref *kref)
2209 struct rbd_img_request *img_request;
2210 struct rbd_obj_request *obj_request;
2211 struct rbd_obj_request *next_obj_request;
2213 img_request = container_of(kref, struct rbd_img_request, kref);
2215 dout("%s: img %p\n", __func__, img_request);
2217 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2218 rbd_img_obj_request_del(img_request, obj_request);
2219 rbd_assert(img_request->obj_request_count == 0);
2221 if (img_request_layered_test(img_request)) {
2222 img_request_layered_clear(img_request);
2223 rbd_dev_parent_put(img_request->rbd_dev);
2226 if (img_request_write_test(img_request) ||
2227 img_request_discard_test(img_request))
2228 ceph_put_snap_context(img_request->snapc);
2230 kmem_cache_free(rbd_img_request_cache, img_request);
2233 static struct rbd_img_request *rbd_parent_request_create(
2234 struct rbd_obj_request *obj_request,
2235 u64 img_offset, u64 length)
2237 struct rbd_img_request *parent_request;
2238 struct rbd_device *rbd_dev;
2240 rbd_assert(obj_request->img_request);
2241 rbd_dev = obj_request->img_request->rbd_dev;
2243 parent_request = rbd_img_request_create(rbd_dev->parent, img_offset,
2244 length, OBJ_OP_READ, NULL);
2245 if (!parent_request)
2248 img_request_child_set(parent_request);
2249 rbd_obj_request_get(obj_request);
2250 parent_request->obj_request = obj_request;
2252 return parent_request;
2255 static void rbd_parent_request_destroy(struct kref *kref)
2257 struct rbd_img_request *parent_request;
2258 struct rbd_obj_request *orig_request;
2260 parent_request = container_of(kref, struct rbd_img_request, kref);
2261 orig_request = parent_request->obj_request;
2263 parent_request->obj_request = NULL;
2264 rbd_obj_request_put(orig_request);
2265 img_request_child_clear(parent_request);
2267 rbd_img_request_destroy(kref);
2270 static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request)
2272 struct rbd_img_request *img_request;
2273 unsigned int xferred;
2277 rbd_assert(obj_request_img_data_test(obj_request));
2278 img_request = obj_request->img_request;
2280 rbd_assert(obj_request->xferred <= (u64)UINT_MAX);
2281 xferred = (unsigned int)obj_request->xferred;
2282 result = obj_request->result;
2284 struct rbd_device *rbd_dev = img_request->rbd_dev;
2285 enum obj_operation_type op_type;
2287 if (img_request_discard_test(img_request))
2288 op_type = OBJ_OP_DISCARD;
2289 else if (img_request_write_test(img_request))
2290 op_type = OBJ_OP_WRITE;
2292 op_type = OBJ_OP_READ;
2294 rbd_warn(rbd_dev, "%s %llx at %llx (%llx)",
2295 obj_op_name(op_type), obj_request->length,
2296 obj_request->img_offset, obj_request->offset);
2297 rbd_warn(rbd_dev, " result %d xferred %x",
2299 if (!img_request->result)
2300 img_request->result = result;
2302 * Need to end I/O on the entire obj_request worth of
2303 * bytes in case of error.
2305 xferred = obj_request->length;
2308 /* Image object requests don't own their page array */
2310 if (obj_request->type == OBJ_REQUEST_PAGES) {
2311 obj_request->pages = NULL;
2312 obj_request->page_count = 0;
2315 if (img_request_child_test(img_request)) {
2316 rbd_assert(img_request->obj_request != NULL);
2317 more = obj_request->which < img_request->obj_request_count - 1;
2319 rbd_assert(img_request->rq != NULL);
2321 more = blk_update_request(img_request->rq, result, xferred);
2323 __blk_mq_end_request(img_request->rq, result);
2329 static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
2331 struct rbd_img_request *img_request;
2332 u32 which = obj_request->which;
2335 rbd_assert(obj_request_img_data_test(obj_request));
2336 img_request = obj_request->img_request;
2338 dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
2339 rbd_assert(img_request != NULL);
2340 rbd_assert(img_request->obj_request_count > 0);
2341 rbd_assert(which != BAD_WHICH);
2342 rbd_assert(which < img_request->obj_request_count);
2344 spin_lock_irq(&img_request->completion_lock);
2345 if (which != img_request->next_completion)
2348 for_each_obj_request_from(img_request, obj_request) {
2350 rbd_assert(which < img_request->obj_request_count);
2352 if (!obj_request_done_test(obj_request))
2354 more = rbd_img_obj_end_request(obj_request);
2358 rbd_assert(more ^ (which == img_request->obj_request_count));
2359 img_request->next_completion = which;
2361 spin_unlock_irq(&img_request->completion_lock);
2362 rbd_img_request_put(img_request);
2365 rbd_img_request_complete(img_request);
2369 * Add individual osd ops to the given ceph_osd_request and prepare
2370 * them for submission. num_ops is the current number of
2371 * osd operations already to the object request.
2373 static void rbd_img_obj_request_fill(struct rbd_obj_request *obj_request,
2374 struct ceph_osd_request *osd_request,
2375 enum obj_operation_type op_type,
2376 unsigned int num_ops)
2378 struct rbd_img_request *img_request = obj_request->img_request;
2379 struct rbd_device *rbd_dev = img_request->rbd_dev;
2380 u64 object_size = rbd_obj_bytes(&rbd_dev->header);
2381 u64 offset = obj_request->offset;
2382 u64 length = obj_request->length;
2386 if (op_type == OBJ_OP_DISCARD) {
2387 if (!offset && length == object_size &&
2388 (!img_request_layered_test(img_request) ||
2389 !obj_request_overlaps_parent(obj_request))) {
2390 opcode = CEPH_OSD_OP_DELETE;
2391 } else if ((offset + length == object_size)) {
2392 opcode = CEPH_OSD_OP_TRUNCATE;
2394 down_read(&rbd_dev->header_rwsem);
2395 img_end = rbd_dev->header.image_size;
2396 up_read(&rbd_dev->header_rwsem);
2398 if (obj_request->img_offset + length == img_end)
2399 opcode = CEPH_OSD_OP_TRUNCATE;
2401 opcode = CEPH_OSD_OP_ZERO;
2403 } else if (op_type == OBJ_OP_WRITE) {
2404 opcode = CEPH_OSD_OP_WRITE;
2405 osd_req_op_alloc_hint_init(osd_request, num_ops,
2406 object_size, object_size);
2409 opcode = CEPH_OSD_OP_READ;
2412 if (opcode == CEPH_OSD_OP_DELETE)
2413 osd_req_op_init(osd_request, num_ops, opcode, 0);
2415 osd_req_op_extent_init(osd_request, num_ops, opcode,
2416 offset, length, 0, 0);
2418 if (obj_request->type == OBJ_REQUEST_BIO)
2419 osd_req_op_extent_osd_data_bio(osd_request, num_ops,
2420 obj_request->bio_list, length);
2421 else if (obj_request->type == OBJ_REQUEST_PAGES)
2422 osd_req_op_extent_osd_data_pages(osd_request, num_ops,
2423 obj_request->pages, length,
2424 offset & ~PAGE_MASK, false, false);
2426 /* Discards are also writes */
2427 if (op_type == OBJ_OP_WRITE || op_type == OBJ_OP_DISCARD)
2428 rbd_osd_req_format_write(obj_request);
2430 rbd_osd_req_format_read(obj_request);
2434 * Split up an image request into one or more object requests, each
2435 * to a different object. The "type" parameter indicates whether
2436 * "data_desc" is the pointer to the head of a list of bio
2437 * structures, or the base of a page array. In either case this
2438 * function assumes data_desc describes memory sufficient to hold
2439 * all data described by the image request.
2441 static int rbd_img_request_fill(struct rbd_img_request *img_request,
2442 enum obj_request_type type,
2445 struct rbd_device *rbd_dev = img_request->rbd_dev;
2446 struct rbd_obj_request *obj_request = NULL;
2447 struct rbd_obj_request *next_obj_request;
2448 struct bio *bio_list = NULL;
2449 unsigned int bio_offset = 0;
2450 struct page **pages = NULL;
2451 enum obj_operation_type op_type;
2455 dout("%s: img %p type %d data_desc %p\n", __func__, img_request,
2456 (int)type, data_desc);
2458 img_offset = img_request->offset;
2459 resid = img_request->length;
2460 rbd_assert(resid > 0);
2461 op_type = rbd_img_request_op_type(img_request);
2463 if (type == OBJ_REQUEST_BIO) {
2464 bio_list = data_desc;
2465 rbd_assert(img_offset ==
2466 bio_list->bi_iter.bi_sector << SECTOR_SHIFT);
2467 } else if (type == OBJ_REQUEST_PAGES) {
2472 struct ceph_osd_request *osd_req;
2473 const char *object_name;
2477 object_name = rbd_segment_name(rbd_dev, img_offset);
2480 offset = rbd_segment_offset(rbd_dev, img_offset);
2481 length = rbd_segment_length(rbd_dev, img_offset, resid);
2482 obj_request = rbd_obj_request_create(object_name,
2483 offset, length, type);
2484 /* object request has its own copy of the object name */
2485 rbd_segment_name_free(object_name);
2490 * set obj_request->img_request before creating the
2491 * osd_request so that it gets the right snapc
2493 rbd_img_obj_request_add(img_request, obj_request);
2495 if (type == OBJ_REQUEST_BIO) {
2496 unsigned int clone_size;
2498 rbd_assert(length <= (u64)UINT_MAX);
2499 clone_size = (unsigned int)length;
2500 obj_request->bio_list =
2501 bio_chain_clone_range(&bio_list,
2505 if (!obj_request->bio_list)
2507 } else if (type == OBJ_REQUEST_PAGES) {
2508 unsigned int page_count;
2510 obj_request->pages = pages;
2511 page_count = (u32)calc_pages_for(offset, length);
2512 obj_request->page_count = page_count;
2513 if ((offset + length) & ~PAGE_MASK)
2514 page_count--; /* more on last page */
2515 pages += page_count;
2518 osd_req = rbd_osd_req_create(rbd_dev, op_type,
2519 (op_type == OBJ_OP_WRITE) ? 2 : 1,
2524 obj_request->osd_req = osd_req;
2525 obj_request->callback = rbd_img_obj_callback;
2526 obj_request->img_offset = img_offset;
2528 rbd_img_obj_request_fill(obj_request, osd_req, op_type, 0);
2530 rbd_img_request_get(img_request);
2532 img_offset += length;
2539 for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2540 rbd_img_obj_request_del(img_request, obj_request);
2546 rbd_osd_copyup_callback(struct rbd_obj_request *obj_request)
2548 struct rbd_img_request *img_request;
2549 struct rbd_device *rbd_dev;
2550 struct page **pages;
2553 dout("%s: obj %p\n", __func__, obj_request);
2555 rbd_assert(obj_request->type == OBJ_REQUEST_BIO ||
2556 obj_request->type == OBJ_REQUEST_NODATA);
2557 rbd_assert(obj_request_img_data_test(obj_request));
2558 img_request = obj_request->img_request;
2559 rbd_assert(img_request);
2561 rbd_dev = img_request->rbd_dev;
2562 rbd_assert(rbd_dev);
2564 pages = obj_request->copyup_pages;
2565 rbd_assert(pages != NULL);
2566 obj_request->copyup_pages = NULL;
2567 page_count = obj_request->copyup_page_count;
2568 rbd_assert(page_count);
2569 obj_request->copyup_page_count = 0;
2570 ceph_release_page_vector(pages, page_count);
2573 * We want the transfer count to reflect the size of the
2574 * original write request. There is no such thing as a
2575 * successful short write, so if the request was successful
2576 * we can just set it to the originally-requested length.
2578 if (!obj_request->result)
2579 obj_request->xferred = obj_request->length;
2581 obj_request_done_set(obj_request);
2585 rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request)
2587 struct rbd_obj_request *orig_request;
2588 struct ceph_osd_request *osd_req;
2589 struct ceph_osd_client *osdc;
2590 struct rbd_device *rbd_dev;
2591 struct page **pages;
2592 enum obj_operation_type op_type;
2597 rbd_assert(img_request_child_test(img_request));
2599 /* First get what we need from the image request */
2601 pages = img_request->copyup_pages;
2602 rbd_assert(pages != NULL);
2603 img_request->copyup_pages = NULL;
2604 page_count = img_request->copyup_page_count;
2605 rbd_assert(page_count);
2606 img_request->copyup_page_count = 0;
2608 orig_request = img_request->obj_request;
2609 rbd_assert(orig_request != NULL);
2610 rbd_assert(obj_request_type_valid(orig_request->type));
2611 img_result = img_request->result;
2612 parent_length = img_request->length;
2613 rbd_assert(parent_length == img_request->xferred);
2614 rbd_img_request_put(img_request);
2616 rbd_assert(orig_request->img_request);
2617 rbd_dev = orig_request->img_request->rbd_dev;
2618 rbd_assert(rbd_dev);
2621 * If the overlap has become 0 (most likely because the
2622 * image has been flattened) we need to free the pages
2623 * and re-submit the original write request.
2625 if (!rbd_dev->parent_overlap) {
2626 struct ceph_osd_client *osdc;
2628 ceph_release_page_vector(pages, page_count);
2629 osdc = &rbd_dev->rbd_client->client->osdc;
2630 img_result = rbd_obj_request_submit(osdc, orig_request);
2639 * The original osd request is of no use to use any more.
2640 * We need a new one that can hold the three ops in a copyup
2641 * request. Allocate the new copyup osd request for the
2642 * original request, and release the old one.
2644 img_result = -ENOMEM;
2645 osd_req = rbd_osd_req_create_copyup(orig_request);
2648 rbd_osd_req_destroy(orig_request->osd_req);
2649 orig_request->osd_req = osd_req;
2650 orig_request->copyup_pages = pages;
2651 orig_request->copyup_page_count = page_count;
2653 /* Initialize the copyup op */
2655 osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup");
2656 osd_req_op_cls_request_data_pages(osd_req, 0, pages, parent_length, 0,
2659 /* Add the other op(s) */
2661 op_type = rbd_img_request_op_type(orig_request->img_request);
2662 rbd_img_obj_request_fill(orig_request, osd_req, op_type, 1);
2664 /* All set, send it off. */
2666 osdc = &rbd_dev->rbd_client->client->osdc;
2667 img_result = rbd_obj_request_submit(osdc, orig_request);
2671 /* Record the error code and complete the request */
2673 orig_request->result = img_result;
2674 orig_request->xferred = 0;
2675 obj_request_done_set(orig_request);
2676 rbd_obj_request_complete(orig_request);
2680 * Read from the parent image the range of data that covers the
2681 * entire target of the given object request. This is used for
2682 * satisfying a layered image write request when the target of an
2683 * object request from the image request does not exist.
2685 * A page array big enough to hold the returned data is allocated
2686 * and supplied to rbd_img_request_fill() as the "data descriptor."
2687 * When the read completes, this page array will be transferred to
2688 * the original object request for the copyup operation.
2690 * If an error occurs, record it as the result of the original
2691 * object request and mark it done so it gets completed.
2693 static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request)
2695 struct rbd_img_request *img_request = NULL;
2696 struct rbd_img_request *parent_request = NULL;
2697 struct rbd_device *rbd_dev;
2700 struct page **pages = NULL;
2704 rbd_assert(obj_request_img_data_test(obj_request));
2705 rbd_assert(obj_request_type_valid(obj_request->type));
2707 img_request = obj_request->img_request;
2708 rbd_assert(img_request != NULL);
2709 rbd_dev = img_request->rbd_dev;
2710 rbd_assert(rbd_dev->parent != NULL);
2713 * Determine the byte range covered by the object in the
2714 * child image to which the original request was to be sent.
2716 img_offset = obj_request->img_offset - obj_request->offset;
2717 length = (u64)1 << rbd_dev->header.obj_order;
2720 * There is no defined parent data beyond the parent
2721 * overlap, so limit what we read at that boundary if
2724 if (img_offset + length > rbd_dev->parent_overlap) {
2725 rbd_assert(img_offset < rbd_dev->parent_overlap);
2726 length = rbd_dev->parent_overlap - img_offset;
2730 * Allocate a page array big enough to receive the data read
2733 page_count = (u32)calc_pages_for(0, length);
2734 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2735 if (IS_ERR(pages)) {
2736 result = PTR_ERR(pages);
2742 parent_request = rbd_parent_request_create(obj_request,
2743 img_offset, length);
2744 if (!parent_request)
2747 result = rbd_img_request_fill(parent_request, OBJ_REQUEST_PAGES, pages);
2750 parent_request->copyup_pages = pages;
2751 parent_request->copyup_page_count = page_count;
2753 parent_request->callback = rbd_img_obj_parent_read_full_callback;
2754 result = rbd_img_request_submit(parent_request);
2758 parent_request->copyup_pages = NULL;
2759 parent_request->copyup_page_count = 0;
2760 parent_request->obj_request = NULL;
2761 rbd_obj_request_put(obj_request);
2764 ceph_release_page_vector(pages, page_count);
2766 rbd_img_request_put(parent_request);
2767 obj_request->result = result;
2768 obj_request->xferred = 0;
2769 obj_request_done_set(obj_request);
2774 static void rbd_img_obj_exists_callback(struct rbd_obj_request *obj_request)
2776 struct rbd_obj_request *orig_request;
2777 struct rbd_device *rbd_dev;
2780 rbd_assert(!obj_request_img_data_test(obj_request));
2783 * All we need from the object request is the original
2784 * request and the result of the STAT op. Grab those, then
2785 * we're done with the request.
2787 orig_request = obj_request->obj_request;
2788 obj_request->obj_request = NULL;
2789 rbd_obj_request_put(orig_request);
2790 rbd_assert(orig_request);
2791 rbd_assert(orig_request->img_request);
2793 result = obj_request->result;
2794 obj_request->result = 0;
2796 dout("%s: obj %p for obj %p result %d %llu/%llu\n", __func__,
2797 obj_request, orig_request, result,
2798 obj_request->xferred, obj_request->length);
2799 rbd_obj_request_put(obj_request);
2802 * If the overlap has become 0 (most likely because the
2803 * image has been flattened) we need to free the pages
2804 * and re-submit the original write request.
2806 rbd_dev = orig_request->img_request->rbd_dev;
2807 if (!rbd_dev->parent_overlap) {
2808 struct ceph_osd_client *osdc;
2810 osdc = &rbd_dev->rbd_client->client->osdc;
2811 result = rbd_obj_request_submit(osdc, orig_request);
2817 * Our only purpose here is to determine whether the object
2818 * exists, and we don't want to treat the non-existence as
2819 * an error. If something else comes back, transfer the
2820 * error to the original request and complete it now.
2823 obj_request_existence_set(orig_request, true);
2824 } else if (result == -ENOENT) {
2825 obj_request_existence_set(orig_request, false);
2826 } else if (result) {
2827 orig_request->result = result;
2832 * Resubmit the original request now that we have recorded
2833 * whether the target object exists.
2835 orig_request->result = rbd_img_obj_request_submit(orig_request);
2837 if (orig_request->result)
2838 rbd_obj_request_complete(orig_request);
2841 static int rbd_img_obj_exists_submit(struct rbd_obj_request *obj_request)
2843 struct rbd_obj_request *stat_request;
2844 struct rbd_device *rbd_dev;
2845 struct ceph_osd_client *osdc;
2846 struct page **pages = NULL;
2852 * The response data for a STAT call consists of:
2859 size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32);
2860 page_count = (u32)calc_pages_for(0, size);
2861 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
2863 return PTR_ERR(pages);
2866 stat_request = rbd_obj_request_create(obj_request->object_name, 0, 0,
2871 rbd_obj_request_get(obj_request);
2872 stat_request->obj_request = obj_request;
2873 stat_request->pages = pages;
2874 stat_request->page_count = page_count;
2876 rbd_assert(obj_request->img_request);
2877 rbd_dev = obj_request->img_request->rbd_dev;
2878 stat_request->osd_req = rbd_osd_req_create(rbd_dev, OBJ_OP_READ, 1,
2880 if (!stat_request->osd_req)
2882 stat_request->callback = rbd_img_obj_exists_callback;
2884 osd_req_op_init(stat_request->osd_req, 0, CEPH_OSD_OP_STAT, 0);
2885 osd_req_op_raw_data_in_pages(stat_request->osd_req, 0, pages, size, 0,
2887 rbd_osd_req_format_read(stat_request);
2889 osdc = &rbd_dev->rbd_client->client->osdc;
2890 ret = rbd_obj_request_submit(osdc, stat_request);
2893 rbd_obj_request_put(obj_request);
2898 static bool img_obj_request_simple(struct rbd_obj_request *obj_request)
2900 struct rbd_img_request *img_request;
2901 struct rbd_device *rbd_dev;
2903 rbd_assert(obj_request_img_data_test(obj_request));
2905 img_request = obj_request->img_request;
2906 rbd_assert(img_request);
2907 rbd_dev = img_request->rbd_dev;
2910 if (!img_request_write_test(img_request) &&
2911 !img_request_discard_test(img_request))
2914 /* Non-layered writes */
2915 if (!img_request_layered_test(img_request))
2919 * Layered writes outside of the parent overlap range don't
2920 * share any data with the parent.
2922 if (!obj_request_overlaps_parent(obj_request))
2926 * Entire-object layered writes - we will overwrite whatever
2927 * parent data there is anyway.
2929 if (!obj_request->offset &&
2930 obj_request->length == rbd_obj_bytes(&rbd_dev->header))
2934 * If the object is known to already exist, its parent data has
2935 * already been copied.
2937 if (obj_request_known_test(obj_request) &&
2938 obj_request_exists_test(obj_request))
2944 static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request)
2946 if (img_obj_request_simple(obj_request)) {
2947 struct rbd_device *rbd_dev;
2948 struct ceph_osd_client *osdc;
2950 rbd_dev = obj_request->img_request->rbd_dev;
2951 osdc = &rbd_dev->rbd_client->client->osdc;
2953 return rbd_obj_request_submit(osdc, obj_request);
2957 * It's a layered write. The target object might exist but
2958 * we may not know that yet. If we know it doesn't exist,
2959 * start by reading the data for the full target object from
2960 * the parent so we can use it for a copyup to the target.
2962 if (obj_request_known_test(obj_request))
2963 return rbd_img_obj_parent_read_full(obj_request);
2965 /* We don't know whether the target exists. Go find out. */
2967 return rbd_img_obj_exists_submit(obj_request);
2970 static int rbd_img_request_submit(struct rbd_img_request *img_request)
2972 struct rbd_obj_request *obj_request;
2973 struct rbd_obj_request *next_obj_request;
2975 dout("%s: img %p\n", __func__, img_request);
2976 for_each_obj_request_safe(img_request, obj_request, next_obj_request) {
2979 ret = rbd_img_obj_request_submit(obj_request);
2987 static void rbd_img_parent_read_callback(struct rbd_img_request *img_request)
2989 struct rbd_obj_request *obj_request;
2990 struct rbd_device *rbd_dev;
2995 rbd_assert(img_request_child_test(img_request));
2997 /* First get what we need from the image request and release it */
2999 obj_request = img_request->obj_request;
3000 img_xferred = img_request->xferred;
3001 img_result = img_request->result;
3002 rbd_img_request_put(img_request);
3005 * If the overlap has become 0 (most likely because the
3006 * image has been flattened) we need to re-submit the
3009 rbd_assert(obj_request);
3010 rbd_assert(obj_request->img_request);
3011 rbd_dev = obj_request->img_request->rbd_dev;
3012 if (!rbd_dev->parent_overlap) {
3013 struct ceph_osd_client *osdc;
3015 osdc = &rbd_dev->rbd_client->client->osdc;
3016 img_result = rbd_obj_request_submit(osdc, obj_request);
3021 obj_request->result = img_result;
3022 if (obj_request->result)
3026 * We need to zero anything beyond the parent overlap
3027 * boundary. Since rbd_img_obj_request_read_callback()
3028 * will zero anything beyond the end of a short read, an
3029 * easy way to do this is to pretend the data from the
3030 * parent came up short--ending at the overlap boundary.
3032 rbd_assert(obj_request->img_offset < U64_MAX - obj_request->length);
3033 obj_end = obj_request->img_offset + obj_request->length;
3034 if (obj_end > rbd_dev->parent_overlap) {
3037 if (obj_request->img_offset < rbd_dev->parent_overlap)
3038 xferred = rbd_dev->parent_overlap -
3039 obj_request->img_offset;
3041 obj_request->xferred = min(img_xferred, xferred);
3043 obj_request->xferred = img_xferred;
3046 rbd_img_obj_request_read_callback(obj_request);
3047 rbd_obj_request_complete(obj_request);
3050 static void rbd_img_parent_read(struct rbd_obj_request *obj_request)
3052 struct rbd_img_request *img_request;
3055 rbd_assert(obj_request_img_data_test(obj_request));
3056 rbd_assert(obj_request->img_request != NULL);
3057 rbd_assert(obj_request->result == (s32) -ENOENT);
3058 rbd_assert(obj_request_type_valid(obj_request->type));
3060 /* rbd_read_finish(obj_request, obj_request->length); */
3061 img_request = rbd_parent_request_create(obj_request,
3062 obj_request->img_offset,
3063 obj_request->length);
3068 if (obj_request->type == OBJ_REQUEST_BIO)
3069 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
3070 obj_request->bio_list);
3072 result = rbd_img_request_fill(img_request, OBJ_REQUEST_PAGES,
3073 obj_request->pages);
3077 img_request->callback = rbd_img_parent_read_callback;
3078 result = rbd_img_request_submit(img_request);
3085 rbd_img_request_put(img_request);
3086 obj_request->result = result;
3087 obj_request->xferred = 0;
3088 obj_request_done_set(obj_request);
3091 static int rbd_obj_notify_ack_sync(struct rbd_device *rbd_dev, u64 notify_id)
3093 struct rbd_obj_request *obj_request;
3094 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3097 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
3098 OBJ_REQUEST_NODATA);
3103 obj_request->osd_req = rbd_osd_req_create(rbd_dev, OBJ_OP_READ, 1,
3105 if (!obj_request->osd_req)
3108 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK,
3110 rbd_osd_req_format_read(obj_request);
3112 ret = rbd_obj_request_submit(osdc, obj_request);
3115 ret = rbd_obj_request_wait(obj_request);
3117 rbd_obj_request_put(obj_request);
3122 static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data)
3124 struct rbd_device *rbd_dev = (struct rbd_device *)data;
3130 dout("%s: \"%s\" notify_id %llu opcode %u\n", __func__,
3131 rbd_dev->header_name, (unsigned long long)notify_id,
3132 (unsigned int)opcode);
3135 * Until adequate refresh error handling is in place, there is
3136 * not much we can do here, except warn.
3138 * See http://tracker.ceph.com/issues/5040
3140 ret = rbd_dev_refresh(rbd_dev);
3142 rbd_warn(rbd_dev, "refresh failed: %d", ret);
3144 ret = rbd_obj_notify_ack_sync(rbd_dev, notify_id);
3146 rbd_warn(rbd_dev, "notify_ack ret %d", ret);
3150 * Send a (un)watch request and wait for the ack. Return a request
3151 * with a ref held on success or error.
3153 static struct rbd_obj_request *rbd_obj_watch_request_helper(
3154 struct rbd_device *rbd_dev,
3157 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3158 struct ceph_options *opts = osdc->client->options;
3159 struct rbd_obj_request *obj_request;
3162 obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0,
3163 OBJ_REQUEST_NODATA);
3165 return ERR_PTR(-ENOMEM);
3167 obj_request->osd_req = rbd_osd_req_create(rbd_dev, OBJ_OP_WRITE, 1,
3169 if (!obj_request->osd_req) {
3174 osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH,
3175 rbd_dev->watch_event->cookie, 0, watch);
3176 rbd_osd_req_format_write(obj_request);
3179 ceph_osdc_set_request_linger(osdc, obj_request->osd_req);
3181 ret = rbd_obj_request_submit(osdc, obj_request);
3185 ret = rbd_obj_request_wait_timeout(obj_request, opts->mount_timeout);
3189 ret = obj_request->result;
3192 rbd_obj_request_end(obj_request);
3199 rbd_obj_request_put(obj_request);
3200 return ERR_PTR(ret);
3204 * Initiate a watch request, synchronously.
3206 static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev)
3208 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3209 struct rbd_obj_request *obj_request;
3212 rbd_assert(!rbd_dev->watch_event);
3213 rbd_assert(!rbd_dev->watch_request);
3215 ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev,
3216 &rbd_dev->watch_event);
3220 obj_request = rbd_obj_watch_request_helper(rbd_dev, true);
3221 if (IS_ERR(obj_request)) {
3222 ceph_osdc_cancel_event(rbd_dev->watch_event);
3223 rbd_dev->watch_event = NULL;
3224 return PTR_ERR(obj_request);
3228 * A watch request is set to linger, so the underlying osd
3229 * request won't go away until we unregister it. We retain
3230 * a pointer to the object request during that time (in
3231 * rbd_dev->watch_request), so we'll keep a reference to it.
3232 * We'll drop that reference after we've unregistered it in
3233 * rbd_dev_header_unwatch_sync().
3235 rbd_dev->watch_request = obj_request;
3241 * Tear down a watch request, synchronously.
3243 static void rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev)
3245 struct rbd_obj_request *obj_request;
3247 rbd_assert(rbd_dev->watch_event);
3248 rbd_assert(rbd_dev->watch_request);
3250 rbd_obj_request_end(rbd_dev->watch_request);
3251 rbd_obj_request_put(rbd_dev->watch_request);
3252 rbd_dev->watch_request = NULL;
3254 obj_request = rbd_obj_watch_request_helper(rbd_dev, false);
3255 if (!IS_ERR(obj_request))
3256 rbd_obj_request_put(obj_request);
3258 rbd_warn(rbd_dev, "unable to tear down watch request (%ld)",
3259 PTR_ERR(obj_request));
3261 ceph_osdc_cancel_event(rbd_dev->watch_event);
3262 rbd_dev->watch_event = NULL;
3266 * Synchronous osd object method call. Returns the number of bytes
3267 * returned in the outbound buffer, or a negative error code.
3269 static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
3270 const char *object_name,
3271 const char *class_name,
3272 const char *method_name,
3273 const void *outbound,
3274 size_t outbound_size,
3276 size_t inbound_size)
3278 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3279 struct rbd_obj_request *obj_request;
3280 struct page **pages;
3285 * Method calls are ultimately read operations. The result
3286 * should placed into the inbound buffer provided. They
3287 * also supply outbound data--parameters for the object
3288 * method. Currently if this is present it will be a
3291 page_count = (u32)calc_pages_for(0, inbound_size);
3292 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
3294 return PTR_ERR(pages);
3297 obj_request = rbd_obj_request_create(object_name, 0, inbound_size,
3302 obj_request->pages = pages;
3303 obj_request->page_count = page_count;
3305 obj_request->osd_req = rbd_osd_req_create(rbd_dev, OBJ_OP_READ, 1,
3307 if (!obj_request->osd_req)
3310 osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL,
3311 class_name, method_name);
3312 if (outbound_size) {
3313 struct ceph_pagelist *pagelist;
3315 pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS);
3319 ceph_pagelist_init(pagelist);
3320 ceph_pagelist_append(pagelist, outbound, outbound_size);
3321 osd_req_op_cls_request_data_pagelist(obj_request->osd_req, 0,
3324 osd_req_op_cls_response_data_pages(obj_request->osd_req, 0,
3325 obj_request->pages, inbound_size,
3327 rbd_osd_req_format_read(obj_request);
3329 ret = rbd_obj_request_submit(osdc, obj_request);
3332 ret = rbd_obj_request_wait(obj_request);
3336 ret = obj_request->result;
3340 rbd_assert(obj_request->xferred < (u64)INT_MAX);
3341 ret = (int)obj_request->xferred;
3342 ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred);
3345 rbd_obj_request_put(obj_request);
3347 ceph_release_page_vector(pages, page_count);
3352 static void rbd_queue_workfn(struct work_struct *work)
3354 struct request *rq = blk_mq_rq_from_pdu(work);
3355 struct rbd_device *rbd_dev = rq->q->queuedata;
3356 struct rbd_img_request *img_request;
3357 struct ceph_snap_context *snapc = NULL;
3358 u64 offset = (u64)blk_rq_pos(rq) << SECTOR_SHIFT;
3359 u64 length = blk_rq_bytes(rq);
3360 enum obj_operation_type op_type;
3364 if (rq->cmd_type != REQ_TYPE_FS) {
3365 dout("%s: non-fs request type %d\n", __func__,
3366 (int) rq->cmd_type);
3371 if (rq->cmd_flags & REQ_DISCARD)
3372 op_type = OBJ_OP_DISCARD;
3373 else if (rq->cmd_flags & REQ_WRITE)
3374 op_type = OBJ_OP_WRITE;
3376 op_type = OBJ_OP_READ;
3378 /* Ignore/skip any zero-length requests */
3381 dout("%s: zero-length request\n", __func__);
3386 /* Only reads are allowed to a read-only device */
3388 if (op_type != OBJ_OP_READ) {
3389 if (rbd_dev->mapping.read_only) {
3393 rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP);
3397 * Quit early if the mapped snapshot no longer exists. It's
3398 * still possible the snapshot will have disappeared by the
3399 * time our request arrives at the osd, but there's no sense in
3400 * sending it if we already know.
3402 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) {
3403 dout("request for non-existent snapshot");
3404 rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP);
3409 if (offset && length > U64_MAX - offset + 1) {
3410 rbd_warn(rbd_dev, "bad request range (%llu~%llu)", offset,
3413 goto err_rq; /* Shouldn't happen */
3416 blk_mq_start_request(rq);
3418 down_read(&rbd_dev->header_rwsem);
3419 mapping_size = rbd_dev->mapping.size;
3420 if (op_type != OBJ_OP_READ) {
3421 snapc = rbd_dev->header.snapc;
3422 ceph_get_snap_context(snapc);
3424 up_read(&rbd_dev->header_rwsem);
3426 if (offset + length > mapping_size) {
3427 rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)", offset,
3428 length, mapping_size);
3433 img_request = rbd_img_request_create(rbd_dev, offset, length, op_type,
3439 img_request->rq = rq;
3441 if (op_type == OBJ_OP_DISCARD)
3442 result = rbd_img_request_fill(img_request, OBJ_REQUEST_NODATA,
3445 result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
3448 goto err_img_request;
3450 result = rbd_img_request_submit(img_request);
3452 goto err_img_request;
3457 rbd_img_request_put(img_request);
3460 rbd_warn(rbd_dev, "%s %llx at %llx result %d",
3461 obj_op_name(op_type), length, offset, result);
3462 ceph_put_snap_context(snapc);
3464 blk_mq_end_request(rq, result);
3467 static int rbd_queue_rq(struct blk_mq_hw_ctx *hctx,
3468 const struct blk_mq_queue_data *bd)
3470 struct request *rq = bd->rq;
3471 struct work_struct *work = blk_mq_rq_to_pdu(rq);
3473 queue_work(rbd_wq, work);
3474 return BLK_MQ_RQ_QUEUE_OK;
3477 static void rbd_free_disk(struct rbd_device *rbd_dev)
3479 struct gendisk *disk = rbd_dev->disk;
3484 rbd_dev->disk = NULL;
3485 if (disk->flags & GENHD_FL_UP) {
3488 blk_cleanup_queue(disk->queue);
3489 blk_mq_free_tag_set(&rbd_dev->tag_set);
3494 static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
3495 const char *object_name,
3496 u64 offset, u64 length, void *buf)
3499 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3500 struct rbd_obj_request *obj_request;
3501 struct page **pages = NULL;
3506 page_count = (u32) calc_pages_for(offset, length);
3507 pages = ceph_alloc_page_vector(page_count, GFP_KERNEL);
3509 return PTR_ERR(pages);
3512 obj_request = rbd_obj_request_create(object_name, offset, length,
3517 obj_request->pages = pages;
3518 obj_request->page_count = page_count;
3520 obj_request->osd_req = rbd_osd_req_create(rbd_dev, OBJ_OP_READ, 1,
3522 if (!obj_request->osd_req)
3525 osd_req_op_extent_init(obj_request->osd_req, 0, CEPH_OSD_OP_READ,
3526 offset, length, 0, 0);
3527 osd_req_op_extent_osd_data_pages(obj_request->osd_req, 0,
3529 obj_request->length,
3530 obj_request->offset & ~PAGE_MASK,
3532 rbd_osd_req_format_read(obj_request);
3534 ret = rbd_obj_request_submit(osdc, obj_request);
3537 ret = rbd_obj_request_wait(obj_request);
3541 ret = obj_request->result;
3545 rbd_assert(obj_request->xferred <= (u64) SIZE_MAX);
3546 size = (size_t) obj_request->xferred;
3547 ceph_copy_from_page_vector(pages, buf, 0, size);
3548 rbd_assert(size <= (size_t)INT_MAX);
3552 rbd_obj_request_put(obj_request);
3554 ceph_release_page_vector(pages, page_count);
3560 * Read the complete header for the given rbd device. On successful
3561 * return, the rbd_dev->header field will contain up-to-date
3562 * information about the image.
3564 static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
3566 struct rbd_image_header_ondisk *ondisk = NULL;
3573 * The complete header will include an array of its 64-bit
3574 * snapshot ids, followed by the names of those snapshots as
3575 * a contiguous block of NUL-terminated strings. Note that
3576 * the number of snapshots could change by the time we read
3577 * it in, in which case we re-read it.
3584 size = sizeof (*ondisk);
3585 size += snap_count * sizeof (struct rbd_image_snap_ondisk);
3587 ondisk = kmalloc(size, GFP_KERNEL);
3591 ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name,
3595 if ((size_t)ret < size) {
3597 rbd_warn(rbd_dev, "short header read (want %zd got %d)",
3601 if (!rbd_dev_ondisk_valid(ondisk)) {
3603 rbd_warn(rbd_dev, "invalid header");
3607 names_size = le64_to_cpu(ondisk->snap_names_len);
3608 want_count = snap_count;
3609 snap_count = le32_to_cpu(ondisk->snap_count);
3610 } while (snap_count != want_count);
3612 ret = rbd_header_from_disk(rbd_dev, ondisk);
3620 * Clear the rbd device's EXISTS flag if the snapshot it's mapped to
3621 * has disappeared from the (just updated) snapshot context.
3623 static void rbd_exists_validate(struct rbd_device *rbd_dev)
3627 if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags))
3630 snap_id = rbd_dev->spec->snap_id;
3631 if (snap_id == CEPH_NOSNAP)
3634 if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX)
3635 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
3638 static void rbd_dev_update_size(struct rbd_device *rbd_dev)
3644 * Don't hold the lock while doing disk operations,
3645 * or lock ordering will conflict with the bdev mutex via:
3646 * rbd_add() -> blkdev_get() -> rbd_open()
3648 spin_lock_irq(&rbd_dev->lock);
3649 removing = test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags);
3650 spin_unlock_irq(&rbd_dev->lock);
3652 * If the device is being removed, rbd_dev->disk has
3653 * been destroyed, so don't try to update its size
3656 size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
3657 dout("setting size to %llu sectors", (unsigned long long)size);
3658 set_capacity(rbd_dev->disk, size);
3659 revalidate_disk(rbd_dev->disk);
3663 static int rbd_dev_refresh(struct rbd_device *rbd_dev)
3668 down_write(&rbd_dev->header_rwsem);
3669 mapping_size = rbd_dev->mapping.size;
3671 ret = rbd_dev_header_info(rbd_dev);
3676 * If there is a parent, see if it has disappeared due to the
3677 * mapped image getting flattened.
3679 if (rbd_dev->parent) {
3680 ret = rbd_dev_v2_parent_info(rbd_dev);
3685 if (rbd_dev->spec->snap_id == CEPH_NOSNAP) {
3686 rbd_dev->mapping.size = rbd_dev->header.image_size;
3688 /* validate mapped snapshot's EXISTS flag */
3689 rbd_exists_validate(rbd_dev);
3693 up_write(&rbd_dev->header_rwsem);
3694 if (!ret && mapping_size != rbd_dev->mapping.size)
3695 rbd_dev_update_size(rbd_dev);
3700 static int rbd_init_request(void *data, struct request *rq,
3701 unsigned int hctx_idx, unsigned int request_idx,
3702 unsigned int numa_node)
3704 struct work_struct *work = blk_mq_rq_to_pdu(rq);
3706 INIT_WORK(work, rbd_queue_workfn);
3710 static struct blk_mq_ops rbd_mq_ops = {
3711 .queue_rq = rbd_queue_rq,
3712 .map_queue = blk_mq_map_queue,
3713 .init_request = rbd_init_request,
3716 static int rbd_init_disk(struct rbd_device *rbd_dev)
3718 struct gendisk *disk;
3719 struct request_queue *q;
3723 /* create gendisk info */
3724 disk = alloc_disk(single_major ?
3725 (1 << RBD_SINGLE_MAJOR_PART_SHIFT) :
3726 RBD_MINORS_PER_MAJOR);
3730 snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
3732 disk->major = rbd_dev->major;
3733 disk->first_minor = rbd_dev->minor;
3735 disk->flags |= GENHD_FL_EXT_DEVT;
3736 disk->fops = &rbd_bd_ops;
3737 disk->private_data = rbd_dev;
3739 memset(&rbd_dev->tag_set, 0, sizeof(rbd_dev->tag_set));
3740 rbd_dev->tag_set.ops = &rbd_mq_ops;
3741 rbd_dev->tag_set.queue_depth = rbd_dev->opts->queue_depth;
3742 rbd_dev->tag_set.numa_node = NUMA_NO_NODE;
3743 rbd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE;
3744 rbd_dev->tag_set.nr_hw_queues = 1;
3745 rbd_dev->tag_set.cmd_size = sizeof(struct work_struct);
3747 err = blk_mq_alloc_tag_set(&rbd_dev->tag_set);
3751 q = blk_mq_init_queue(&rbd_dev->tag_set);
3757 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q);
3758 /* QUEUE_FLAG_ADD_RANDOM is off by default for blk-mq */
3760 /* set io sizes to object size */
3761 segment_size = rbd_obj_bytes(&rbd_dev->header);
3762 blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
3763 blk_queue_max_segments(q, segment_size / SECTOR_SIZE);
3764 blk_queue_max_segment_size(q, segment_size);
3765 blk_queue_io_min(q, segment_size);
3766 blk_queue_io_opt(q, segment_size);
3768 /* enable the discard support */
3769 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
3770 q->limits.discard_granularity = segment_size;
3771 q->limits.discard_alignment = segment_size;
3772 blk_queue_max_discard_sectors(q, segment_size / SECTOR_SIZE);
3773 q->limits.discard_zeroes_data = 1;
3777 q->queuedata = rbd_dev;
3779 rbd_dev->disk = disk;
3783 blk_mq_free_tag_set(&rbd_dev->tag_set);
3793 static struct rbd_device *dev_to_rbd_dev(struct device *dev)
3795 return container_of(dev, struct rbd_device, dev);
3798 static ssize_t rbd_size_show(struct device *dev,
3799 struct device_attribute *attr, char *buf)
3801 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3803 return sprintf(buf, "%llu\n",
3804 (unsigned long long)rbd_dev->mapping.size);
3808 * Note this shows the features for whatever's mapped, which is not
3809 * necessarily the base image.
3811 static ssize_t rbd_features_show(struct device *dev,
3812 struct device_attribute *attr, char *buf)
3814 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3816 return sprintf(buf, "0x%016llx\n",
3817 (unsigned long long)rbd_dev->mapping.features);
3820 static ssize_t rbd_major_show(struct device *dev,
3821 struct device_attribute *attr, char *buf)
3823 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3826 return sprintf(buf, "%d\n", rbd_dev->major);
3828 return sprintf(buf, "(none)\n");
3831 static ssize_t rbd_minor_show(struct device *dev,
3832 struct device_attribute *attr, char *buf)
3834 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3836 return sprintf(buf, "%d\n", rbd_dev->minor);
3839 static ssize_t rbd_client_id_show(struct device *dev,
3840 struct device_attribute *attr, char *buf)
3842 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3844 return sprintf(buf, "client%lld\n",
3845 ceph_client_id(rbd_dev->rbd_client->client));
3848 static ssize_t rbd_pool_show(struct device *dev,
3849 struct device_attribute *attr, char *buf)
3851 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3853 return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
3856 static ssize_t rbd_pool_id_show(struct device *dev,
3857 struct device_attribute *attr, char *buf)
3859 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3861 return sprintf(buf, "%llu\n",
3862 (unsigned long long) rbd_dev->spec->pool_id);
3865 static ssize_t rbd_name_show(struct device *dev,
3866 struct device_attribute *attr, char *buf)
3868 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3870 if (rbd_dev->spec->image_name)
3871 return sprintf(buf, "%s\n", rbd_dev->spec->image_name);
3873 return sprintf(buf, "(unknown)\n");
3876 static ssize_t rbd_image_id_show(struct device *dev,
3877 struct device_attribute *attr, char *buf)
3879 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3881 return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
3885 * Shows the name of the currently-mapped snapshot (or
3886 * RBD_SNAP_HEAD_NAME for the base image).
3888 static ssize_t rbd_snap_show(struct device *dev,
3889 struct device_attribute *attr,
3892 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3894 return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
3898 * For a v2 image, shows the chain of parent images, separated by empty
3899 * lines. For v1 images or if there is no parent, shows "(no parent
3902 static ssize_t rbd_parent_show(struct device *dev,
3903 struct device_attribute *attr,
3906 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3909 if (!rbd_dev->parent)
3910 return sprintf(buf, "(no parent image)\n");
3912 for ( ; rbd_dev->parent; rbd_dev = rbd_dev->parent) {
3913 struct rbd_spec *spec = rbd_dev->parent_spec;
3915 count += sprintf(&buf[count], "%s"
3916 "pool_id %llu\npool_name %s\n"
3917 "image_id %s\nimage_name %s\n"
3918 "snap_id %llu\nsnap_name %s\n"
3920 !count ? "" : "\n", /* first? */
3921 spec->pool_id, spec->pool_name,
3922 spec->image_id, spec->image_name ?: "(unknown)",
3923 spec->snap_id, spec->snap_name,
3924 rbd_dev->parent_overlap);
3930 static ssize_t rbd_image_refresh(struct device *dev,
3931 struct device_attribute *attr,
3935 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
3938 ret = rbd_dev_refresh(rbd_dev);
3945 static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
3946 static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL);
3947 static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
3948 static DEVICE_ATTR(minor, S_IRUGO, rbd_minor_show, NULL);
3949 static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
3950 static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
3951 static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL);
3952 static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
3953 static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL);
3954 static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
3955 static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
3956 static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL);
3958 static struct attribute *rbd_attrs[] = {
3959 &dev_attr_size.attr,
3960 &dev_attr_features.attr,
3961 &dev_attr_major.attr,
3962 &dev_attr_minor.attr,
3963 &dev_attr_client_id.attr,
3964 &dev_attr_pool.attr,
3965 &dev_attr_pool_id.attr,
3966 &dev_attr_name.attr,
3967 &dev_attr_image_id.attr,
3968 &dev_attr_current_snap.attr,
3969 &dev_attr_parent.attr,
3970 &dev_attr_refresh.attr,
3974 static struct attribute_group rbd_attr_group = {
3978 static const struct attribute_group *rbd_attr_groups[] = {
3983 static void rbd_sysfs_dev_release(struct device *dev)
3987 static struct device_type rbd_device_type = {
3989 .groups = rbd_attr_groups,
3990 .release = rbd_sysfs_dev_release,
3993 static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
3995 kref_get(&spec->kref);
4000 static void rbd_spec_free(struct kref *kref);
4001 static void rbd_spec_put(struct rbd_spec *spec)
4004 kref_put(&spec->kref, rbd_spec_free);
4007 static struct rbd_spec *rbd_spec_alloc(void)
4009 struct rbd_spec *spec;
4011 spec = kzalloc(sizeof (*spec), GFP_KERNEL);
4015 spec->pool_id = CEPH_NOPOOL;
4016 spec->snap_id = CEPH_NOSNAP;
4017 kref_init(&spec->kref);
4022 static void rbd_spec_free(struct kref *kref)
4024 struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);
4026 kfree(spec->pool_name);
4027 kfree(spec->image_id);
4028 kfree(spec->image_name);
4029 kfree(spec->snap_name);
4033 static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
4034 struct rbd_spec *spec,
4035 struct rbd_options *opts)
4037 struct rbd_device *rbd_dev;
4039 rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL);
4043 spin_lock_init(&rbd_dev->lock);
4045 atomic_set(&rbd_dev->parent_ref, 0);
4046 INIT_LIST_HEAD(&rbd_dev->node);
4047 init_rwsem(&rbd_dev->header_rwsem);
4049 rbd_dev->rbd_client = rbdc;
4050 rbd_dev->spec = spec;
4051 rbd_dev->opts = opts;
4053 /* Initialize the layout used for all rbd requests */
4055 rbd_dev->layout.fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
4056 rbd_dev->layout.fl_stripe_count = cpu_to_le32(1);
4057 rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER);
4058 rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id);
4063 static void rbd_dev_destroy(struct rbd_device *rbd_dev)
4065 rbd_put_client(rbd_dev->rbd_client);
4066 rbd_spec_put(rbd_dev->spec);
4067 kfree(rbd_dev->opts);
4072 * Get the size and object order for an image snapshot, or if
4073 * snap_id is CEPH_NOSNAP, gets this information for the base
4076 static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
4077 u8 *order, u64 *snap_size)
4079 __le64 snapid = cpu_to_le64(snap_id);
4084 } __attribute__ ((packed)) size_buf = { 0 };
4086 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4088 &snapid, sizeof (snapid),
4089 &size_buf, sizeof (size_buf));
4090 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4093 if (ret < sizeof (size_buf))
4097 *order = size_buf.order;
4098 dout(" order %u", (unsigned int)*order);
4100 *snap_size = le64_to_cpu(size_buf.size);
4102 dout(" snap_id 0x%016llx snap_size = %llu\n",
4103 (unsigned long long)snap_id,
4104 (unsigned long long)*snap_size);
4109 static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
4111 return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
4112 &rbd_dev->header.obj_order,
4113 &rbd_dev->header.image_size);
4116 static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
4122 reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL);
4126 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4127 "rbd", "get_object_prefix", NULL, 0,
4128 reply_buf, RBD_OBJ_PREFIX_LEN_MAX);
4129 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4134 rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
4135 p + ret, NULL, GFP_NOIO);
4138 if (IS_ERR(rbd_dev->header.object_prefix)) {
4139 ret = PTR_ERR(rbd_dev->header.object_prefix);
4140 rbd_dev->header.object_prefix = NULL;
4142 dout(" object_prefix = %s\n", rbd_dev->header.object_prefix);
4150 static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
4153 __le64 snapid = cpu_to_le64(snap_id);
4157 } __attribute__ ((packed)) features_buf = { 0 };
4161 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4162 "rbd", "get_features",
4163 &snapid, sizeof (snapid),
4164 &features_buf, sizeof (features_buf));
4165 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4168 if (ret < sizeof (features_buf))
4171 incompat = le64_to_cpu(features_buf.incompat);
4172 if (incompat & ~RBD_FEATURES_SUPPORTED)
4175 *snap_features = le64_to_cpu(features_buf.features);
4177 dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
4178 (unsigned long long)snap_id,
4179 (unsigned long long)*snap_features,
4180 (unsigned long long)le64_to_cpu(features_buf.incompat));
4185 static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
4187 return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
4188 &rbd_dev->header.features);
4191 static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
4193 struct rbd_spec *parent_spec;
4195 void *reply_buf = NULL;
4205 parent_spec = rbd_spec_alloc();
4209 size = sizeof (__le64) + /* pool_id */
4210 sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */
4211 sizeof (__le64) + /* snap_id */
4212 sizeof (__le64); /* overlap */
4213 reply_buf = kmalloc(size, GFP_KERNEL);
4219 snapid = cpu_to_le64(rbd_dev->spec->snap_id);
4220 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4221 "rbd", "get_parent",
4222 &snapid, sizeof (snapid),
4224 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4229 end = reply_buf + ret;
4231 ceph_decode_64_safe(&p, end, pool_id, out_err);
4232 if (pool_id == CEPH_NOPOOL) {
4234 * Either the parent never existed, or we have
4235 * record of it but the image got flattened so it no
4236 * longer has a parent. When the parent of a
4237 * layered image disappears we immediately set the
4238 * overlap to 0. The effect of this is that all new
4239 * requests will be treated as if the image had no
4242 if (rbd_dev->parent_overlap) {
4243 rbd_dev->parent_overlap = 0;
4244 rbd_dev_parent_put(rbd_dev);
4245 pr_info("%s: clone image has been flattened\n",
4246 rbd_dev->disk->disk_name);
4249 goto out; /* No parent? No problem. */
4252 /* The ceph file layout needs to fit pool id in 32 bits */
4255 if (pool_id > (u64)U32_MAX) {
4256 rbd_warn(NULL, "parent pool id too large (%llu > %u)",
4257 (unsigned long long)pool_id, U32_MAX);
4261 image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
4262 if (IS_ERR(image_id)) {
4263 ret = PTR_ERR(image_id);
4266 ceph_decode_64_safe(&p, end, snap_id, out_err);
4267 ceph_decode_64_safe(&p, end, overlap, out_err);
4270 * The parent won't change (except when the clone is
4271 * flattened, already handled that). So we only need to
4272 * record the parent spec we have not already done so.
4274 if (!rbd_dev->parent_spec) {
4275 parent_spec->pool_id = pool_id;
4276 parent_spec->image_id = image_id;
4277 parent_spec->snap_id = snap_id;
4278 rbd_dev->parent_spec = parent_spec;
4279 parent_spec = NULL; /* rbd_dev now owns this */
4285 * We always update the parent overlap. If it's zero we issue
4286 * a warning, as we will proceed as if there was no parent.
4290 /* refresh, careful to warn just once */
4291 if (rbd_dev->parent_overlap)
4293 "clone now standalone (overlap became 0)");
4296 rbd_warn(rbd_dev, "clone is standalone (overlap 0)");
4299 rbd_dev->parent_overlap = overlap;
4305 rbd_spec_put(parent_spec);
4310 static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
4314 __le64 stripe_count;
4315 } __attribute__ ((packed)) striping_info_buf = { 0 };
4316 size_t size = sizeof (striping_info_buf);
4323 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4324 "rbd", "get_stripe_unit_count", NULL, 0,
4325 (char *)&striping_info_buf, size);
4326 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4333 * We don't actually support the "fancy striping" feature
4334 * (STRIPINGV2) yet, but if the striping sizes are the
4335 * defaults the behavior is the same as before. So find
4336 * out, and only fail if the image has non-default values.
4339 obj_size = (u64)1 << rbd_dev->header.obj_order;
4340 p = &striping_info_buf;
4341 stripe_unit = ceph_decode_64(&p);
4342 if (stripe_unit != obj_size) {
4343 rbd_warn(rbd_dev, "unsupported stripe unit "
4344 "(got %llu want %llu)",
4345 stripe_unit, obj_size);
4348 stripe_count = ceph_decode_64(&p);
4349 if (stripe_count != 1) {
4350 rbd_warn(rbd_dev, "unsupported stripe count "
4351 "(got %llu want 1)", stripe_count);
4354 rbd_dev->header.stripe_unit = stripe_unit;
4355 rbd_dev->header.stripe_count = stripe_count;
4360 static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
4362 size_t image_id_size;
4367 void *reply_buf = NULL;
4369 char *image_name = NULL;
4372 rbd_assert(!rbd_dev->spec->image_name);
4374 len = strlen(rbd_dev->spec->image_id);
4375 image_id_size = sizeof (__le32) + len;
4376 image_id = kmalloc(image_id_size, GFP_KERNEL);
4381 end = image_id + image_id_size;
4382 ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
4384 size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
4385 reply_buf = kmalloc(size, GFP_KERNEL);
4389 ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY,
4390 "rbd", "dir_get_name",
4391 image_id, image_id_size,
4396 end = reply_buf + ret;
4398 image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
4399 if (IS_ERR(image_name))
4402 dout("%s: name is %s len is %zd\n", __func__, image_name, len);
4410 static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4412 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
4413 const char *snap_name;
4416 /* Skip over names until we find the one we are looking for */
4418 snap_name = rbd_dev->header.snap_names;
4419 while (which < snapc->num_snaps) {
4420 if (!strcmp(name, snap_name))
4421 return snapc->snaps[which];
4422 snap_name += strlen(snap_name) + 1;
4428 static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4430 struct ceph_snap_context *snapc = rbd_dev->header.snapc;
4435 for (which = 0; !found && which < snapc->num_snaps; which++) {
4436 const char *snap_name;
4438 snap_id = snapc->snaps[which];
4439 snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
4440 if (IS_ERR(snap_name)) {
4441 /* ignore no-longer existing snapshots */
4442 if (PTR_ERR(snap_name) == -ENOENT)
4447 found = !strcmp(name, snap_name);
4450 return found ? snap_id : CEPH_NOSNAP;
4454 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
4455 * no snapshot by that name is found, or if an error occurs.
4457 static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
4459 if (rbd_dev->image_format == 1)
4460 return rbd_v1_snap_id_by_name(rbd_dev, name);
4462 return rbd_v2_snap_id_by_name(rbd_dev, name);
4466 * An image being mapped will have everything but the snap id.
4468 static int rbd_spec_fill_snap_id(struct rbd_device *rbd_dev)
4470 struct rbd_spec *spec = rbd_dev->spec;
4472 rbd_assert(spec->pool_id != CEPH_NOPOOL && spec->pool_name);
4473 rbd_assert(spec->image_id && spec->image_name);
4474 rbd_assert(spec->snap_name);
4476 if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
4479 snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
4480 if (snap_id == CEPH_NOSNAP)
4483 spec->snap_id = snap_id;
4485 spec->snap_id = CEPH_NOSNAP;
4492 * A parent image will have all ids but none of the names.
4494 * All names in an rbd spec are dynamically allocated. It's OK if we
4495 * can't figure out the name for an image id.
4497 static int rbd_spec_fill_names(struct rbd_device *rbd_dev)
4499 struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
4500 struct rbd_spec *spec = rbd_dev->spec;
4501 const char *pool_name;
4502 const char *image_name;
4503 const char *snap_name;
4506 rbd_assert(spec->pool_id != CEPH_NOPOOL);
4507 rbd_assert(spec->image_id);
4508 rbd_assert(spec->snap_id != CEPH_NOSNAP);
4510 /* Get the pool name; we have to make our own copy of this */
4512 pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
4514 rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
4517 pool_name = kstrdup(pool_name, GFP_KERNEL);
4521 /* Fetch the image name; tolerate failure here */
4523 image_name = rbd_dev_image_name(rbd_dev);
4525 rbd_warn(rbd_dev, "unable to get image name");
4527 /* Fetch the snapshot name */
4529 snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
4530 if (IS_ERR(snap_name)) {
4531 ret = PTR_ERR(snap_name);
4535 spec->pool_name = pool_name;
4536 spec->image_name = image_name;
4537 spec->snap_name = snap_name;
4547 static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
4556 struct ceph_snap_context *snapc;
4560 * We'll need room for the seq value (maximum snapshot id),
4561 * snapshot count, and array of that many snapshot ids.
4562 * For now we have a fixed upper limit on the number we're
4563 * prepared to receive.
4565 size = sizeof (__le64) + sizeof (__le32) +
4566 RBD_MAX_SNAP_COUNT * sizeof (__le64);
4567 reply_buf = kzalloc(size, GFP_KERNEL);
4571 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4572 "rbd", "get_snapcontext", NULL, 0,
4574 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4579 end = reply_buf + ret;
4581 ceph_decode_64_safe(&p, end, seq, out);
4582 ceph_decode_32_safe(&p, end, snap_count, out);
4585 * Make sure the reported number of snapshot ids wouldn't go
4586 * beyond the end of our buffer. But before checking that,
4587 * make sure the computed size of the snapshot context we
4588 * allocate is representable in a size_t.
4590 if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
4595 if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
4599 snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
4605 for (i = 0; i < snap_count; i++)
4606 snapc->snaps[i] = ceph_decode_64(&p);
4608 ceph_put_snap_context(rbd_dev->header.snapc);
4609 rbd_dev->header.snapc = snapc;
4611 dout(" snap context seq = %llu, snap_count = %u\n",
4612 (unsigned long long)seq, (unsigned int)snap_count);
4619 static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
4630 size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
4631 reply_buf = kmalloc(size, GFP_KERNEL);
4633 return ERR_PTR(-ENOMEM);
4635 snapid = cpu_to_le64(snap_id);
4636 ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name,
4637 "rbd", "get_snapshot_name",
4638 &snapid, sizeof (snapid),
4640 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4642 snap_name = ERR_PTR(ret);
4647 end = reply_buf + ret;
4648 snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
4649 if (IS_ERR(snap_name))
4652 dout(" snap_id 0x%016llx snap_name = %s\n",
4653 (unsigned long long)snap_id, snap_name);
4660 static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
4662 bool first_time = rbd_dev->header.object_prefix == NULL;
4665 ret = rbd_dev_v2_image_size(rbd_dev);
4670 ret = rbd_dev_v2_header_onetime(rbd_dev);
4675 ret = rbd_dev_v2_snap_context(rbd_dev);
4676 if (ret && first_time) {
4677 kfree(rbd_dev->header.object_prefix);
4678 rbd_dev->header.object_prefix = NULL;
4684 static int rbd_dev_header_info(struct rbd_device *rbd_dev)
4686 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
4688 if (rbd_dev->image_format == 1)
4689 return rbd_dev_v1_header_info(rbd_dev);
4691 return rbd_dev_v2_header_info(rbd_dev);
4694 static int rbd_bus_add_dev(struct rbd_device *rbd_dev)
4699 dev = &rbd_dev->dev;
4700 dev->bus = &rbd_bus_type;
4701 dev->type = &rbd_device_type;
4702 dev->parent = &rbd_root_dev;
4703 dev->release = rbd_dev_device_release;
4704 dev_set_name(dev, "%d", rbd_dev->dev_id);
4705 ret = device_register(dev);
4710 static void rbd_bus_del_dev(struct rbd_device *rbd_dev)
4712 device_unregister(&rbd_dev->dev);
4716 * Get a unique rbd identifier for the given new rbd_dev, and add
4717 * the rbd_dev to the global list.
4719 static int rbd_dev_id_get(struct rbd_device *rbd_dev)
4723 new_dev_id = ida_simple_get(&rbd_dev_id_ida,
4724 0, minor_to_rbd_dev_id(1 << MINORBITS),
4729 rbd_dev->dev_id = new_dev_id;
4731 spin_lock(&rbd_dev_list_lock);
4732 list_add_tail(&rbd_dev->node, &rbd_dev_list);
4733 spin_unlock(&rbd_dev_list_lock);
4735 dout("rbd_dev %p given dev id %d\n", rbd_dev, rbd_dev->dev_id);
4741 * Remove an rbd_dev from the global list, and record that its
4742 * identifier is no longer in use.
4744 static void rbd_dev_id_put(struct rbd_device *rbd_dev)
4746 spin_lock(&rbd_dev_list_lock);
4747 list_del_init(&rbd_dev->node);
4748 spin_unlock(&rbd_dev_list_lock);
4750 ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id);
4752 dout("rbd_dev %p released dev id %d\n", rbd_dev, rbd_dev->dev_id);
4756 * Skips over white space at *buf, and updates *buf to point to the
4757 * first found non-space character (if any). Returns the length of
4758 * the token (string of non-white space characters) found. Note
4759 * that *buf must be terminated with '\0'.
4761 static inline size_t next_token(const char **buf)
4764 * These are the characters that produce nonzero for
4765 * isspace() in the "C" and "POSIX" locales.
4767 const char *spaces = " \f\n\r\t\v";
4769 *buf += strspn(*buf, spaces); /* Find start of token */
4771 return strcspn(*buf, spaces); /* Return token length */
4775 * Finds the next token in *buf, dynamically allocates a buffer big
4776 * enough to hold a copy of it, and copies the token into the new
4777 * buffer. The copy is guaranteed to be terminated with '\0'. Note
4778 * that a duplicate buffer is created even for a zero-length token.
4780 * Returns a pointer to the newly-allocated duplicate, or a null
4781 * pointer if memory for the duplicate was not available. If
4782 * the lenp argument is a non-null pointer, the length of the token
4783 * (not including the '\0') is returned in *lenp.
4785 * If successful, the *buf pointer will be updated to point beyond
4786 * the end of the found token.
4788 * Note: uses GFP_KERNEL for allocation.
4790 static inline char *dup_token(const char **buf, size_t *lenp)
4795 len = next_token(buf);
4796 dup = kmemdup(*buf, len + 1, GFP_KERNEL);
4799 *(dup + len) = '\0';
4809 * Parse the options provided for an "rbd add" (i.e., rbd image
4810 * mapping) request. These arrive via a write to /sys/bus/rbd/add,
4811 * and the data written is passed here via a NUL-terminated buffer.
4812 * Returns 0 if successful or an error code otherwise.
4814 * The information extracted from these options is recorded in
4815 * the other parameters which return dynamically-allocated
4818 * The address of a pointer that will refer to a ceph options
4819 * structure. Caller must release the returned pointer using
4820 * ceph_destroy_options() when it is no longer needed.
4822 * Address of an rbd options pointer. Fully initialized by
4823 * this function; caller must release with kfree().
4825 * Address of an rbd image specification pointer. Fully
4826 * initialized by this function based on parsed options.
4827 * Caller must release with rbd_spec_put().
4829 * The options passed take this form:
4830 * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
4833 * A comma-separated list of one or more monitor addresses.
4834 * A monitor address is an ip address, optionally followed
4835 * by a port number (separated by a colon).
4836 * I.e.: ip1[:port1][,ip2[:port2]...]
4838 * A comma-separated list of ceph and/or rbd options.
4840 * The name of the rados pool containing the rbd image.
4842 * The name of the image in that pool to map.
4844 * An optional snapshot id. If provided, the mapping will
4845 * present data from the image at the time that snapshot was
4846 * created. The image head is used if no snapshot id is
4847 * provided. Snapshot mappings are always read-only.
4849 static int rbd_add_parse_args(const char *buf,
4850 struct ceph_options **ceph_opts,
4851 struct rbd_options **opts,
4852 struct rbd_spec **rbd_spec)
4856 const char *mon_addrs;
4858 size_t mon_addrs_size;
4859 struct rbd_spec *spec = NULL;
4860 struct rbd_options *rbd_opts = NULL;
4861 struct ceph_options *copts;
4864 /* The first four tokens are required */
4866 len = next_token(&buf);
4868 rbd_warn(NULL, "no monitor address(es) provided");
4872 mon_addrs_size = len + 1;
4876 options = dup_token(&buf, NULL);
4880 rbd_warn(NULL, "no options provided");
4884 spec = rbd_spec_alloc();
4888 spec->pool_name = dup_token(&buf, NULL);
4889 if (!spec->pool_name)
4891 if (!*spec->pool_name) {
4892 rbd_warn(NULL, "no pool name provided");
4896 spec->image_name = dup_token(&buf, NULL);
4897 if (!spec->image_name)
4899 if (!*spec->image_name) {
4900 rbd_warn(NULL, "no image name provided");
4905 * Snapshot name is optional; default is to use "-"
4906 * (indicating the head/no snapshot).
4908 len = next_token(&buf);
4910 buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
4911 len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
4912 } else if (len > RBD_MAX_SNAP_NAME_LEN) {
4913 ret = -ENAMETOOLONG;
4916 snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
4919 *(snap_name + len) = '\0';
4920 spec->snap_name = snap_name;
4922 /* Initialize all rbd options to the defaults */
4924 rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL);
4928 rbd_opts->read_only = RBD_READ_ONLY_DEFAULT;
4929 rbd_opts->queue_depth = RBD_QUEUE_DEPTH_DEFAULT;
4931 copts = ceph_parse_options(options, mon_addrs,
4932 mon_addrs + mon_addrs_size - 1,
4933 parse_rbd_opts_token, rbd_opts);
4934 if (IS_ERR(copts)) {
4935 ret = PTR_ERR(copts);
4956 * Return pool id (>= 0) or a negative error code.
4958 static int rbd_add_get_pool_id(struct rbd_client *rbdc, const char *pool_name)
4960 struct ceph_options *opts = rbdc->client->options;
4966 ret = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, pool_name);
4967 if (ret == -ENOENT && tries++ < 1) {
4968 ret = ceph_monc_do_get_version(&rbdc->client->monc, "osdmap",
4973 if (rbdc->client->osdc.osdmap->epoch < newest_epoch) {
4974 ceph_monc_request_next_osdmap(&rbdc->client->monc);
4975 (void) ceph_monc_wait_osdmap(&rbdc->client->monc,
4977 opts->mount_timeout);
4980 /* the osdmap we have is new enough */
4989 * An rbd format 2 image has a unique identifier, distinct from the
4990 * name given to it by the user. Internally, that identifier is
4991 * what's used to specify the names of objects related to the image.
4993 * A special "rbd id" object is used to map an rbd image name to its
4994 * id. If that object doesn't exist, then there is no v2 rbd image
4995 * with the supplied name.
4997 * This function will record the given rbd_dev's image_id field if
4998 * it can be determined, and in that case will return 0. If any
4999 * errors occur a negative errno will be returned and the rbd_dev's
5000 * image_id field will be unchanged (and should be NULL).
5002 static int rbd_dev_image_id(struct rbd_device *rbd_dev)
5011 * When probing a parent image, the image id is already
5012 * known (and the image name likely is not). There's no
5013 * need to fetch the image id again in this case. We
5014 * do still need to set the image format though.
5016 if (rbd_dev->spec->image_id) {
5017 rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;
5023 * First, see if the format 2 image id file exists, and if
5024 * so, get the image's persistent id from it.
5026 size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name);
5027 object_name = kmalloc(size, GFP_NOIO);
5030 sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name);
5031 dout("rbd id object name is %s\n", object_name);
5033 /* Response will be an encoded string, which includes a length */
5035 size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
5036 response = kzalloc(size, GFP_NOIO);
5042 /* If it doesn't exist we'll assume it's a format 1 image */
5044 ret = rbd_obj_method_sync(rbd_dev, object_name,
5045 "rbd", "get_id", NULL, 0,
5046 response, RBD_IMAGE_ID_LEN_MAX);
5047 dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5048 if (ret == -ENOENT) {
5049 image_id = kstrdup("", GFP_KERNEL);
5050 ret = image_id ? 0 : -ENOMEM;
5052 rbd_dev->image_format = 1;
5053 } else if (ret >= 0) {
5056 image_id = ceph_extract_encoded_string(&p, p + ret,
5058 ret = PTR_ERR_OR_ZERO(image_id);
5060 rbd_dev->image_format = 2;
5064 rbd_dev->spec->image_id = image_id;
5065 dout("image_id is %s\n", image_id);
5075 * Undo whatever state changes are made by v1 or v2 header info
5078 static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
5080 struct rbd_image_header *header;
5082 rbd_dev_parent_put(rbd_dev);
5084 /* Free dynamic fields from the header, then zero it out */
5086 header = &rbd_dev->header;
5087 ceph_put_snap_context(header->snapc);
5088 kfree(header->snap_sizes);
5089 kfree(header->snap_names);
5090 kfree(header->object_prefix);
5091 memset(header, 0, sizeof (*header));
5094 static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev)
5098 ret = rbd_dev_v2_object_prefix(rbd_dev);
5103 * Get the and check features for the image. Currently the
5104 * features are assumed to never change.
5106 ret = rbd_dev_v2_features(rbd_dev);
5110 /* If the image supports fancy striping, get its parameters */
5112 if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
5113 ret = rbd_dev_v2_striping_info(rbd_dev);
5117 /* No support for crypto and compression type format 2 images */
5121 rbd_dev->header.features = 0;
5122 kfree(rbd_dev->header.object_prefix);
5123 rbd_dev->header.object_prefix = NULL;
5128 static int rbd_dev_probe_parent(struct rbd_device *rbd_dev)
5130 struct rbd_device *parent = NULL;
5131 struct rbd_spec *parent_spec;
5132 struct rbd_client *rbdc;
5135 if (!rbd_dev->parent_spec)
5138 * We need to pass a reference to the client and the parent
5139 * spec when creating the parent rbd_dev. Images related by
5140 * parent/child relationships always share both.
5142 parent_spec = rbd_spec_get(rbd_dev->parent_spec);
5143 rbdc = __rbd_get_client(rbd_dev->rbd_client);
5146 parent = rbd_dev_create(rbdc, parent_spec, NULL);
5150 ret = rbd_dev_image_probe(parent, false);
5153 rbd_dev->parent = parent;
5154 atomic_set(&rbd_dev->parent_ref, 1);
5159 rbd_dev_unparent(rbd_dev);
5160 rbd_dev_destroy(parent);
5162 rbd_put_client(rbdc);
5163 rbd_spec_put(parent_spec);
5169 static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
5173 /* Get an id and fill in device name. */
5175 ret = rbd_dev_id_get(rbd_dev);
5179 BUILD_BUG_ON(DEV_NAME_LEN
5180 < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH);
5181 sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id);
5183 /* Record our major and minor device numbers. */
5185 if (!single_major) {
5186 ret = register_blkdev(0, rbd_dev->name);
5190 rbd_dev->major = ret;
5193 rbd_dev->major = rbd_major;
5194 rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id);
5197 /* Set up the blkdev mapping. */
5199 ret = rbd_init_disk(rbd_dev);
5201 goto err_out_blkdev;
5203 ret = rbd_dev_mapping_set(rbd_dev);
5207 set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
5208 set_disk_ro(rbd_dev->disk, rbd_dev->mapping.read_only);
5210 ret = rbd_bus_add_dev(rbd_dev);
5212 goto err_out_mapping;
5214 /* Everything's ready. Announce the disk to the world. */
5216 set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
5217 add_disk(rbd_dev->disk);
5219 pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name,
5220 (unsigned long long) rbd_dev->mapping.size);
5225 rbd_dev_mapping_clear(rbd_dev);
5227 rbd_free_disk(rbd_dev);
5230 unregister_blkdev(rbd_dev->major, rbd_dev->name);
5232 rbd_dev_id_put(rbd_dev);
5233 rbd_dev_mapping_clear(rbd_dev);
5238 static int rbd_dev_header_name(struct rbd_device *rbd_dev)
5240 struct rbd_spec *spec = rbd_dev->spec;
5243 /* Record the header object name for this rbd image. */
5245 rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
5247 if (rbd_dev->image_format == 1)
5248 size = strlen(spec->image_name) + sizeof (RBD_SUFFIX);
5250 size = sizeof (RBD_HEADER_PREFIX) + strlen(spec->image_id);
5252 rbd_dev->header_name = kmalloc(size, GFP_KERNEL);
5253 if (!rbd_dev->header_name)
5256 if (rbd_dev->image_format == 1)
5257 sprintf(rbd_dev->header_name, "%s%s",
5258 spec->image_name, RBD_SUFFIX);
5260 sprintf(rbd_dev->header_name, "%s%s",
5261 RBD_HEADER_PREFIX, spec->image_id);
5265 static void rbd_dev_image_release(struct rbd_device *rbd_dev)
5267 rbd_dev_unprobe(rbd_dev);
5268 kfree(rbd_dev->header_name);
5269 rbd_dev->header_name = NULL;
5270 rbd_dev->image_format = 0;
5271 kfree(rbd_dev->spec->image_id);
5272 rbd_dev->spec->image_id = NULL;
5274 rbd_dev_destroy(rbd_dev);
5278 * Probe for the existence of the header object for the given rbd
5279 * device. If this image is the one being mapped (i.e., not a
5280 * parent), initiate a watch on its header object before using that
5281 * object to get detailed information about the rbd image.
5283 static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping)
5288 * Get the id from the image id object. Unless there's an
5289 * error, rbd_dev->spec->image_id will be filled in with
5290 * a dynamically-allocated string, and rbd_dev->image_format
5291 * will be set to either 1 or 2.
5293 ret = rbd_dev_image_id(rbd_dev);
5297 ret = rbd_dev_header_name(rbd_dev);
5299 goto err_out_format;
5302 ret = rbd_dev_header_watch_sync(rbd_dev);
5305 pr_info("image %s/%s does not exist\n",
5306 rbd_dev->spec->pool_name,
5307 rbd_dev->spec->image_name);
5308 goto out_header_name;
5312 ret = rbd_dev_header_info(rbd_dev);
5317 * If this image is the one being mapped, we have pool name and
5318 * id, image name and id, and snap name - need to fill snap id.
5319 * Otherwise this is a parent image, identified by pool, image
5320 * and snap ids - need to fill in names for those ids.
5323 ret = rbd_spec_fill_snap_id(rbd_dev);
5325 ret = rbd_spec_fill_names(rbd_dev);
5328 pr_info("snap %s/%s@%s does not exist\n",
5329 rbd_dev->spec->pool_name,
5330 rbd_dev->spec->image_name,
5331 rbd_dev->spec->snap_name);
5335 if (rbd_dev->header.features & RBD_FEATURE_LAYERING) {
5336 ret = rbd_dev_v2_parent_info(rbd_dev);
5341 * Need to warn users if this image is the one being
5342 * mapped and has a parent.
5344 if (mapping && rbd_dev->parent_spec)
5346 "WARNING: kernel layering is EXPERIMENTAL!");
5349 ret = rbd_dev_probe_parent(rbd_dev);
5353 dout("discovered format %u image, header name is %s\n",
5354 rbd_dev->image_format, rbd_dev->header_name);
5358 rbd_dev_unprobe(rbd_dev);
5361 rbd_dev_header_unwatch_sync(rbd_dev);
5363 kfree(rbd_dev->header_name);
5364 rbd_dev->header_name = NULL;
5366 rbd_dev->image_format = 0;
5367 kfree(rbd_dev->spec->image_id);
5368 rbd_dev->spec->image_id = NULL;
5372 static ssize_t do_rbd_add(struct bus_type *bus,
5376 struct rbd_device *rbd_dev = NULL;
5377 struct ceph_options *ceph_opts = NULL;
5378 struct rbd_options *rbd_opts = NULL;
5379 struct rbd_spec *spec = NULL;
5380 struct rbd_client *rbdc;
5384 if (!try_module_get(THIS_MODULE))
5387 /* parse add command */
5388 rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
5390 goto err_out_module;
5392 rbdc = rbd_get_client(ceph_opts);
5399 rc = rbd_add_get_pool_id(rbdc, spec->pool_name);
5402 pr_info("pool %s does not exist\n", spec->pool_name);
5403 goto err_out_client;
5405 spec->pool_id = (u64)rc;
5407 /* The ceph file layout needs to fit pool id in 32 bits */
5409 if (spec->pool_id > (u64)U32_MAX) {
5410 rbd_warn(NULL, "pool id too large (%llu > %u)",
5411 (unsigned long long)spec->pool_id, U32_MAX);
5413 goto err_out_client;
5416 rbd_dev = rbd_dev_create(rbdc, spec, rbd_opts);
5418 goto err_out_client;
5419 rbdc = NULL; /* rbd_dev now owns this */
5420 spec = NULL; /* rbd_dev now owns this */
5421 rbd_opts = NULL; /* rbd_dev now owns this */
5423 rc = rbd_dev_image_probe(rbd_dev, true);
5425 goto err_out_rbd_dev;
5427 /* If we are mapping a snapshot it must be marked read-only */
5429 read_only = rbd_dev->opts->read_only;
5430 if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
5432 rbd_dev->mapping.read_only = read_only;
5434 rc = rbd_dev_device_setup(rbd_dev);
5437 * rbd_dev_header_unwatch_sync() can't be moved into
5438 * rbd_dev_image_release() without refactoring, see
5439 * commit 1f3ef78861ac.
5441 rbd_dev_header_unwatch_sync(rbd_dev);
5442 rbd_dev_image_release(rbd_dev);
5443 goto err_out_module;
5449 rbd_dev_destroy(rbd_dev);
5451 rbd_put_client(rbdc);
5456 module_put(THIS_MODULE);
5458 dout("Error adding device %s\n", buf);
5463 static ssize_t rbd_add(struct bus_type *bus,
5470 return do_rbd_add(bus, buf, count);
5473 static ssize_t rbd_add_single_major(struct bus_type *bus,
5477 return do_rbd_add(bus, buf, count);
5480 static void rbd_dev_device_release(struct device *dev)
5482 struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
5484 rbd_free_disk(rbd_dev);
5485 clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
5486 rbd_dev_mapping_clear(rbd_dev);
5488 unregister_blkdev(rbd_dev->major, rbd_dev->name);
5489 rbd_dev_id_put(rbd_dev);
5490 rbd_dev_mapping_clear(rbd_dev);
5493 static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
5495 while (rbd_dev->parent) {
5496 struct rbd_device *first = rbd_dev;
5497 struct rbd_device *second = first->parent;
5498 struct rbd_device *third;
5501 * Follow to the parent with no grandparent and
5504 while (second && (third = second->parent)) {
5509 rbd_dev_image_release(second);
5510 first->parent = NULL;
5511 first->parent_overlap = 0;
5513 rbd_assert(first->parent_spec);
5514 rbd_spec_put(first->parent_spec);
5515 first->parent_spec = NULL;
5519 static ssize_t do_rbd_remove(struct bus_type *bus,
5523 struct rbd_device *rbd_dev = NULL;
5524 struct list_head *tmp;
5527 bool already = false;
5530 ret = kstrtoul(buf, 10, &ul);
5534 /* convert to int; abort if we lost anything in the conversion */
5540 spin_lock(&rbd_dev_list_lock);
5541 list_for_each(tmp, &rbd_dev_list) {
5542 rbd_dev = list_entry(tmp, struct rbd_device, node);
5543 if (rbd_dev->dev_id == dev_id) {
5549 spin_lock_irq(&rbd_dev->lock);
5550 if (rbd_dev->open_count)
5553 already = test_and_set_bit(RBD_DEV_FLAG_REMOVING,
5555 spin_unlock_irq(&rbd_dev->lock);
5557 spin_unlock(&rbd_dev_list_lock);
5558 if (ret < 0 || already)
5561 rbd_dev_header_unwatch_sync(rbd_dev);
5563 * flush remaining watch callbacks - these must be complete
5564 * before the osd_client is shutdown
5566 dout("%s: flushing notifies", __func__);
5567 ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc);
5570 * Don't free anything from rbd_dev->disk until after all
5571 * notifies are completely processed. Otherwise
5572 * rbd_bus_del_dev() will race with rbd_watch_cb(), resulting
5573 * in a potential use after free of rbd_dev->disk or rbd_dev.
5575 rbd_bus_del_dev(rbd_dev);
5576 rbd_dev_image_release(rbd_dev);
5577 module_put(THIS_MODULE);
5582 static ssize_t rbd_remove(struct bus_type *bus,
5589 return do_rbd_remove(bus, buf, count);
5592 static ssize_t rbd_remove_single_major(struct bus_type *bus,
5596 return do_rbd_remove(bus, buf, count);
5600 * create control files in sysfs
5603 static int rbd_sysfs_init(void)
5607 ret = device_register(&rbd_root_dev);
5611 ret = bus_register(&rbd_bus_type);
5613 device_unregister(&rbd_root_dev);
5618 static void rbd_sysfs_cleanup(void)
5620 bus_unregister(&rbd_bus_type);
5621 device_unregister(&rbd_root_dev);
5624 static int rbd_slab_init(void)
5626 rbd_assert(!rbd_img_request_cache);
5627 rbd_img_request_cache = kmem_cache_create("rbd_img_request",
5628 sizeof (struct rbd_img_request),
5629 __alignof__(struct rbd_img_request),
5631 if (!rbd_img_request_cache)
5634 rbd_assert(!rbd_obj_request_cache);
5635 rbd_obj_request_cache = kmem_cache_create("rbd_obj_request",
5636 sizeof (struct rbd_obj_request),
5637 __alignof__(struct rbd_obj_request),
5639 if (!rbd_obj_request_cache)
5642 rbd_assert(!rbd_segment_name_cache);
5643 rbd_segment_name_cache = kmem_cache_create("rbd_segment_name",
5644 CEPH_MAX_OID_NAME_LEN + 1, 1, 0, NULL);
5645 if (rbd_segment_name_cache)
5648 if (rbd_obj_request_cache) {
5649 kmem_cache_destroy(rbd_obj_request_cache);
5650 rbd_obj_request_cache = NULL;
5653 kmem_cache_destroy(rbd_img_request_cache);
5654 rbd_img_request_cache = NULL;
5659 static void rbd_slab_exit(void)
5661 rbd_assert(rbd_segment_name_cache);
5662 kmem_cache_destroy(rbd_segment_name_cache);
5663 rbd_segment_name_cache = NULL;
5665 rbd_assert(rbd_obj_request_cache);
5666 kmem_cache_destroy(rbd_obj_request_cache);
5667 rbd_obj_request_cache = NULL;
5669 rbd_assert(rbd_img_request_cache);
5670 kmem_cache_destroy(rbd_img_request_cache);
5671 rbd_img_request_cache = NULL;
5674 static int __init rbd_init(void)
5678 if (!libceph_compatible(NULL)) {
5679 rbd_warn(NULL, "libceph incompatibility (quitting)");
5683 rc = rbd_slab_init();
5688 * The number of active work items is limited by the number of
5689 * rbd devices * queue depth, so leave @max_active at default.
5691 rbd_wq = alloc_workqueue(RBD_DRV_NAME, WQ_MEM_RECLAIM, 0);
5698 rbd_major = register_blkdev(0, RBD_DRV_NAME);
5699 if (rbd_major < 0) {
5705 rc = rbd_sysfs_init();
5707 goto err_out_blkdev;
5710 pr_info("loaded (major %d)\n", rbd_major);
5712 pr_info("loaded\n");
5718 unregister_blkdev(rbd_major, RBD_DRV_NAME);
5720 destroy_workqueue(rbd_wq);
5726 static void __exit rbd_exit(void)
5728 ida_destroy(&rbd_dev_id_ida);
5729 rbd_sysfs_cleanup();
5731 unregister_blkdev(rbd_major, RBD_DRV_NAME);
5732 destroy_workqueue(rbd_wq);
5736 module_init(rbd_init);
5737 module_exit(rbd_exit);
5739 MODULE_AUTHOR("Alex Elder <elder@inktank.com>");
5740 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
5741 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
5742 /* following authorship retained from original osdblk.c */
5743 MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");
5745 MODULE_DESCRIPTION("RADOS Block Device (RBD) driver");
5746 MODULE_LICENSE("GPL");