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Commit | Line | Data |
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1 | ||
2 | /* | |
3 | rbd.c -- Export ceph rados objects as a Linux block device | |
4 | ||
5 | ||
6 | based on drivers/block/osdblk.c: | |
7 | ||
8 | Copyright 2009 Red Hat, Inc. | |
9 | ||
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. | |
13 | ||
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. | |
18 | ||
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. | |
22 | ||
23 | ||
24 | ||
25 | For usage instructions, please refer to: | |
26 | ||
27 | Documentation/ABI/testing/sysfs-bus-rbd | |
28 | ||
29 | */ | |
30 | ||
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> | |
37 | ||
38 | #include <linux/kernel.h> | |
39 | #include <linux/device.h> | |
40 | #include <linux/module.h> | |
41 | #include <linux/fs.h> | |
42 | #include <linux/blkdev.h> | |
43 | #include <linux/slab.h> | |
44 | #include <linux/idr.h> | |
45 | ||
46 | #include "rbd_types.h" | |
47 | ||
48 | #define RBD_DEBUG /* Activate rbd_assert() calls */ | |
49 | ||
50 | /* | |
51 | * The basic unit of block I/O is a sector. It is interpreted in a | |
52 | * number of contexts in Linux (blk, bio, genhd), but the default is | |
53 | * universally 512 bytes. These symbols are just slightly more | |
54 | * meaningful than the bare numbers they represent. | |
55 | */ | |
56 | #define SECTOR_SHIFT 9 | |
57 | #define SECTOR_SIZE (1ULL << SECTOR_SHIFT) | |
58 | ||
59 | /* | |
60 | * Increment the given counter and return its updated value. | |
61 | * If the counter is already 0 it will not be incremented. | |
62 | * If the counter is already at its maximum value returns | |
63 | * -EINVAL without updating it. | |
64 | */ | |
65 | static int atomic_inc_return_safe(atomic_t *v) | |
66 | { | |
67 | unsigned int counter; | |
68 | ||
69 | counter = (unsigned int)__atomic_add_unless(v, 1, 0); | |
70 | if (counter <= (unsigned int)INT_MAX) | |
71 | return (int)counter; | |
72 | ||
73 | atomic_dec(v); | |
74 | ||
75 | return -EINVAL; | |
76 | } | |
77 | ||
78 | /* Decrement the counter. Return the resulting value, or -EINVAL */ | |
79 | static int atomic_dec_return_safe(atomic_t *v) | |
80 | { | |
81 | int counter; | |
82 | ||
83 | counter = atomic_dec_return(v); | |
84 | if (counter >= 0) | |
85 | return counter; | |
86 | ||
87 | atomic_inc(v); | |
88 | ||
89 | return -EINVAL; | |
90 | } | |
91 | ||
92 | #define RBD_DRV_NAME "rbd" | |
93 | ||
94 | #define RBD_MINORS_PER_MAJOR 256 | |
95 | #define RBD_SINGLE_MAJOR_PART_SHIFT 4 | |
96 | ||
97 | #define RBD_SNAP_DEV_NAME_PREFIX "snap_" | |
98 | #define RBD_MAX_SNAP_NAME_LEN \ | |
99 | (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1)) | |
100 | ||
101 | #define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */ | |
102 | ||
103 | #define RBD_SNAP_HEAD_NAME "-" | |
104 | ||
105 | #define BAD_SNAP_INDEX U32_MAX /* invalid index into snap array */ | |
106 | ||
107 | /* This allows a single page to hold an image name sent by OSD */ | |
108 | #define RBD_IMAGE_NAME_LEN_MAX (PAGE_SIZE - sizeof (__le32) - 1) | |
109 | #define RBD_IMAGE_ID_LEN_MAX 64 | |
110 | ||
111 | #define RBD_OBJ_PREFIX_LEN_MAX 64 | |
112 | ||
113 | /* Feature bits */ | |
114 | ||
115 | #define RBD_FEATURE_LAYERING (1<<0) | |
116 | #define RBD_FEATURE_STRIPINGV2 (1<<1) | |
117 | #define RBD_FEATURES_ALL \ | |
118 | (RBD_FEATURE_LAYERING | RBD_FEATURE_STRIPINGV2) | |
119 | ||
120 | /* Features supported by this (client software) implementation. */ | |
121 | ||
122 | #define RBD_FEATURES_SUPPORTED (RBD_FEATURES_ALL) | |
123 | ||
124 | /* | |
125 | * An RBD device name will be "rbd#", where the "rbd" comes from | |
126 | * RBD_DRV_NAME above, and # is a unique integer identifier. | |
127 | * MAX_INT_FORMAT_WIDTH is used in ensuring DEV_NAME_LEN is big | |
128 | * enough to hold all possible device names. | |
129 | */ | |
130 | #define DEV_NAME_LEN 32 | |
131 | #define MAX_INT_FORMAT_WIDTH ((5 * sizeof (int)) / 2 + 1) | |
132 | ||
133 | /* | |
134 | * block device image metadata (in-memory version) | |
135 | */ | |
136 | struct rbd_image_header { | |
137 | /* These six fields never change for a given rbd image */ | |
138 | char *object_prefix; | |
139 | __u8 obj_order; | |
140 | __u8 crypt_type; | |
141 | __u8 comp_type; | |
142 | u64 stripe_unit; | |
143 | u64 stripe_count; | |
144 | u64 features; /* Might be changeable someday? */ | |
145 | ||
146 | /* The remaining fields need to be updated occasionally */ | |
147 | u64 image_size; | |
148 | struct ceph_snap_context *snapc; | |
149 | char *snap_names; /* format 1 only */ | |
150 | u64 *snap_sizes; /* format 1 only */ | |
151 | }; | |
152 | ||
153 | /* | |
154 | * An rbd image specification. | |
155 | * | |
156 | * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely | |
157 | * identify an image. Each rbd_dev structure includes a pointer to | |
158 | * an rbd_spec structure that encapsulates this identity. | |
159 | * | |
160 | * Each of the id's in an rbd_spec has an associated name. For a | |
161 | * user-mapped image, the names are supplied and the id's associated | |
162 | * with them are looked up. For a layered image, a parent image is | |
163 | * defined by the tuple, and the names are looked up. | |
164 | * | |
165 | * An rbd_dev structure contains a parent_spec pointer which is | |
166 | * non-null if the image it represents is a child in a layered | |
167 | * image. This pointer will refer to the rbd_spec structure used | |
168 | * by the parent rbd_dev for its own identity (i.e., the structure | |
169 | * is shared between the parent and child). | |
170 | * | |
171 | * Since these structures are populated once, during the discovery | |
172 | * phase of image construction, they are effectively immutable so | |
173 | * we make no effort to synchronize access to them. | |
174 | * | |
175 | * Note that code herein does not assume the image name is known (it | |
176 | * could be a null pointer). | |
177 | */ | |
178 | struct rbd_spec { | |
179 | u64 pool_id; | |
180 | const char *pool_name; | |
181 | ||
182 | const char *image_id; | |
183 | const char *image_name; | |
184 | ||
185 | u64 snap_id; | |
186 | const char *snap_name; | |
187 | ||
188 | struct kref kref; | |
189 | }; | |
190 | ||
191 | /* | |
192 | * an instance of the client. multiple devices may share an rbd client. | |
193 | */ | |
194 | struct rbd_client { | |
195 | struct ceph_client *client; | |
196 | struct kref kref; | |
197 | struct list_head node; | |
198 | }; | |
199 | ||
200 | struct rbd_img_request; | |
201 | typedef void (*rbd_img_callback_t)(struct rbd_img_request *); | |
202 | ||
203 | #define BAD_WHICH U32_MAX /* Good which or bad which, which? */ | |
204 | ||
205 | struct rbd_obj_request; | |
206 | typedef void (*rbd_obj_callback_t)(struct rbd_obj_request *); | |
207 | ||
208 | enum obj_request_type { | |
209 | OBJ_REQUEST_NODATA, OBJ_REQUEST_BIO, OBJ_REQUEST_PAGES | |
210 | }; | |
211 | ||
212 | enum obj_req_flags { | |
213 | OBJ_REQ_DONE, /* completion flag: not done = 0, done = 1 */ | |
214 | OBJ_REQ_IMG_DATA, /* object usage: standalone = 0, image = 1 */ | |
215 | OBJ_REQ_KNOWN, /* EXISTS flag valid: no = 0, yes = 1 */ | |
216 | OBJ_REQ_EXISTS, /* target exists: no = 0, yes = 1 */ | |
217 | }; | |
218 | ||
219 | struct rbd_obj_request { | |
220 | const char *object_name; | |
221 | u64 offset; /* object start byte */ | |
222 | u64 length; /* bytes from offset */ | |
223 | unsigned long flags; | |
224 | ||
225 | /* | |
226 | * An object request associated with an image will have its | |
227 | * img_data flag set; a standalone object request will not. | |
228 | * | |
229 | * A standalone object request will have which == BAD_WHICH | |
230 | * and a null obj_request pointer. | |
231 | * | |
232 | * An object request initiated in support of a layered image | |
233 | * object (to check for its existence before a write) will | |
234 | * have which == BAD_WHICH and a non-null obj_request pointer. | |
235 | * | |
236 | * Finally, an object request for rbd image data will have | |
237 | * which != BAD_WHICH, and will have a non-null img_request | |
238 | * pointer. The value of which will be in the range | |
239 | * 0..(img_request->obj_request_count-1). | |
240 | */ | |
241 | union { | |
242 | struct rbd_obj_request *obj_request; /* STAT op */ | |
243 | struct { | |
244 | struct rbd_img_request *img_request; | |
245 | u64 img_offset; | |
246 | /* links for img_request->obj_requests list */ | |
247 | struct list_head links; | |
248 | }; | |
249 | }; | |
250 | u32 which; /* posn image request list */ | |
251 | ||
252 | enum obj_request_type type; | |
253 | union { | |
254 | struct bio *bio_list; | |
255 | struct { | |
256 | struct page **pages; | |
257 | u32 page_count; | |
258 | }; | |
259 | }; | |
260 | struct page **copyup_pages; | |
261 | u32 copyup_page_count; | |
262 | ||
263 | struct ceph_osd_request *osd_req; | |
264 | ||
265 | u64 xferred; /* bytes transferred */ | |
266 | int result; | |
267 | ||
268 | rbd_obj_callback_t callback; | |
269 | struct completion completion; | |
270 | ||
271 | struct kref kref; | |
272 | }; | |
273 | ||
274 | enum img_req_flags { | |
275 | IMG_REQ_WRITE, /* I/O direction: read = 0, write = 1 */ | |
276 | IMG_REQ_CHILD, /* initiator: block = 0, child image = 1 */ | |
277 | IMG_REQ_LAYERED, /* ENOENT handling: normal = 0, layered = 1 */ | |
278 | }; | |
279 | ||
280 | struct rbd_img_request { | |
281 | struct rbd_device *rbd_dev; | |
282 | u64 offset; /* starting image byte offset */ | |
283 | u64 length; /* byte count from offset */ | |
284 | unsigned long flags; | |
285 | union { | |
286 | u64 snap_id; /* for reads */ | |
287 | struct ceph_snap_context *snapc; /* for writes */ | |
288 | }; | |
289 | union { | |
290 | struct request *rq; /* block request */ | |
291 | struct rbd_obj_request *obj_request; /* obj req initiator */ | |
292 | }; | |
293 | struct page **copyup_pages; | |
294 | u32 copyup_page_count; | |
295 | spinlock_t completion_lock;/* protects next_completion */ | |
296 | u32 next_completion; | |
297 | rbd_img_callback_t callback; | |
298 | u64 xferred;/* aggregate bytes transferred */ | |
299 | int result; /* first nonzero obj_request result */ | |
300 | ||
301 | u32 obj_request_count; | |
302 | struct list_head obj_requests; /* rbd_obj_request structs */ | |
303 | ||
304 | struct kref kref; | |
305 | }; | |
306 | ||
307 | #define for_each_obj_request(ireq, oreq) \ | |
308 | list_for_each_entry(oreq, &(ireq)->obj_requests, links) | |
309 | #define for_each_obj_request_from(ireq, oreq) \ | |
310 | list_for_each_entry_from(oreq, &(ireq)->obj_requests, links) | |
311 | #define for_each_obj_request_safe(ireq, oreq, n) \ | |
312 | list_for_each_entry_safe_reverse(oreq, n, &(ireq)->obj_requests, links) | |
313 | ||
314 | struct rbd_mapping { | |
315 | u64 size; | |
316 | u64 features; | |
317 | bool read_only; | |
318 | }; | |
319 | ||
320 | /* | |
321 | * a single device | |
322 | */ | |
323 | struct rbd_device { | |
324 | int dev_id; /* blkdev unique id */ | |
325 | ||
326 | int major; /* blkdev assigned major */ | |
327 | int minor; | |
328 | struct gendisk *disk; /* blkdev's gendisk and rq */ | |
329 | ||
330 | u32 image_format; /* Either 1 or 2 */ | |
331 | struct rbd_client *rbd_client; | |
332 | ||
333 | char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */ | |
334 | ||
335 | spinlock_t lock; /* queue, flags, open_count */ | |
336 | ||
337 | struct rbd_image_header header; | |
338 | unsigned long flags; /* possibly lock protected */ | |
339 | struct rbd_spec *spec; | |
340 | ||
341 | char *header_name; | |
342 | ||
343 | struct ceph_file_layout layout; | |
344 | ||
345 | struct ceph_osd_event *watch_event; | |
346 | struct rbd_obj_request *watch_request; | |
347 | ||
348 | struct rbd_spec *parent_spec; | |
349 | u64 parent_overlap; | |
350 | atomic_t parent_ref; | |
351 | struct rbd_device *parent; | |
352 | ||
353 | /* protects updating the header */ | |
354 | struct rw_semaphore header_rwsem; | |
355 | ||
356 | struct rbd_mapping mapping; | |
357 | ||
358 | struct list_head node; | |
359 | ||
360 | /* sysfs related */ | |
361 | struct device dev; | |
362 | unsigned long open_count; /* protected by lock */ | |
363 | }; | |
364 | ||
365 | /* | |
366 | * Flag bits for rbd_dev->flags. If atomicity is required, | |
367 | * rbd_dev->lock is used to protect access. | |
368 | * | |
369 | * Currently, only the "removing" flag (which is coupled with the | |
370 | * "open_count" field) requires atomic access. | |
371 | */ | |
372 | enum rbd_dev_flags { | |
373 | RBD_DEV_FLAG_EXISTS, /* mapped snapshot has not been deleted */ | |
374 | RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */ | |
375 | }; | |
376 | ||
377 | static DEFINE_MUTEX(client_mutex); /* Serialize client creation */ | |
378 | ||
379 | static LIST_HEAD(rbd_dev_list); /* devices */ | |
380 | static DEFINE_SPINLOCK(rbd_dev_list_lock); | |
381 | ||
382 | static LIST_HEAD(rbd_client_list); /* clients */ | |
383 | static DEFINE_SPINLOCK(rbd_client_list_lock); | |
384 | ||
385 | /* Slab caches for frequently-allocated structures */ | |
386 | ||
387 | static struct kmem_cache *rbd_img_request_cache; | |
388 | static struct kmem_cache *rbd_obj_request_cache; | |
389 | static struct kmem_cache *rbd_segment_name_cache; | |
390 | ||
391 | static int rbd_major; | |
392 | static DEFINE_IDA(rbd_dev_id_ida); | |
393 | ||
394 | /* | |
395 | * Default to false for now, as single-major requires >= 0.75 version of | |
396 | * userspace rbd utility. | |
397 | */ | |
398 | static bool single_major = false; | |
399 | module_param(single_major, bool, S_IRUGO); | |
400 | MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: false)"); | |
401 | ||
402 | static int rbd_img_request_submit(struct rbd_img_request *img_request); | |
403 | ||
404 | static void rbd_dev_device_release(struct device *dev); | |
405 | ||
406 | static ssize_t rbd_add(struct bus_type *bus, const char *buf, | |
407 | size_t count); | |
408 | static ssize_t rbd_remove(struct bus_type *bus, const char *buf, | |
409 | size_t count); | |
410 | static ssize_t rbd_add_single_major(struct bus_type *bus, const char *buf, | |
411 | size_t count); | |
412 | static ssize_t rbd_remove_single_major(struct bus_type *bus, const char *buf, | |
413 | size_t count); | |
414 | static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping); | |
415 | static void rbd_spec_put(struct rbd_spec *spec); | |
416 | ||
417 | static int rbd_dev_id_to_minor(int dev_id) | |
418 | { | |
419 | return dev_id << RBD_SINGLE_MAJOR_PART_SHIFT; | |
420 | } | |
421 | ||
422 | static int minor_to_rbd_dev_id(int minor) | |
423 | { | |
424 | return minor >> RBD_SINGLE_MAJOR_PART_SHIFT; | |
425 | } | |
426 | ||
427 | static BUS_ATTR(add, S_IWUSR, NULL, rbd_add); | |
428 | static BUS_ATTR(remove, S_IWUSR, NULL, rbd_remove); | |
429 | static BUS_ATTR(add_single_major, S_IWUSR, NULL, rbd_add_single_major); | |
430 | static BUS_ATTR(remove_single_major, S_IWUSR, NULL, rbd_remove_single_major); | |
431 | ||
432 | static struct attribute *rbd_bus_attrs[] = { | |
433 | &bus_attr_add.attr, | |
434 | &bus_attr_remove.attr, | |
435 | &bus_attr_add_single_major.attr, | |
436 | &bus_attr_remove_single_major.attr, | |
437 | NULL, | |
438 | }; | |
439 | ||
440 | static umode_t rbd_bus_is_visible(struct kobject *kobj, | |
441 | struct attribute *attr, int index) | |
442 | { | |
443 | if (!single_major && | |
444 | (attr == &bus_attr_add_single_major.attr || | |
445 | attr == &bus_attr_remove_single_major.attr)) | |
446 | return 0; | |
447 | ||
448 | return attr->mode; | |
449 | } | |
450 | ||
451 | static const struct attribute_group rbd_bus_group = { | |
452 | .attrs = rbd_bus_attrs, | |
453 | .is_visible = rbd_bus_is_visible, | |
454 | }; | |
455 | __ATTRIBUTE_GROUPS(rbd_bus); | |
456 | ||
457 | static struct bus_type rbd_bus_type = { | |
458 | .name = "rbd", | |
459 | .bus_groups = rbd_bus_groups, | |
460 | }; | |
461 | ||
462 | static void rbd_root_dev_release(struct device *dev) | |
463 | { | |
464 | } | |
465 | ||
466 | static struct device rbd_root_dev = { | |
467 | .init_name = "rbd", | |
468 | .release = rbd_root_dev_release, | |
469 | }; | |
470 | ||
471 | static __printf(2, 3) | |
472 | void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...) | |
473 | { | |
474 | struct va_format vaf; | |
475 | va_list args; | |
476 | ||
477 | va_start(args, fmt); | |
478 | vaf.fmt = fmt; | |
479 | vaf.va = &args; | |
480 | ||
481 | if (!rbd_dev) | |
482 | printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf); | |
483 | else if (rbd_dev->disk) | |
484 | printk(KERN_WARNING "%s: %s: %pV\n", | |
485 | RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf); | |
486 | else if (rbd_dev->spec && rbd_dev->spec->image_name) | |
487 | printk(KERN_WARNING "%s: image %s: %pV\n", | |
488 | RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf); | |
489 | else if (rbd_dev->spec && rbd_dev->spec->image_id) | |
490 | printk(KERN_WARNING "%s: id %s: %pV\n", | |
491 | RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf); | |
492 | else /* punt */ | |
493 | printk(KERN_WARNING "%s: rbd_dev %p: %pV\n", | |
494 | RBD_DRV_NAME, rbd_dev, &vaf); | |
495 | va_end(args); | |
496 | } | |
497 | ||
498 | #ifdef RBD_DEBUG | |
499 | #define rbd_assert(expr) \ | |
500 | if (unlikely(!(expr))) { \ | |
501 | printk(KERN_ERR "\nAssertion failure in %s() " \ | |
502 | "at line %d:\n\n" \ | |
503 | "\trbd_assert(%s);\n\n", \ | |
504 | __func__, __LINE__, #expr); \ | |
505 | BUG(); \ | |
506 | } | |
507 | #else /* !RBD_DEBUG */ | |
508 | # define rbd_assert(expr) ((void) 0) | |
509 | #endif /* !RBD_DEBUG */ | |
510 | ||
511 | static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request); | |
512 | static void rbd_img_parent_read(struct rbd_obj_request *obj_request); | |
513 | static void rbd_dev_remove_parent(struct rbd_device *rbd_dev); | |
514 | ||
515 | static int rbd_dev_refresh(struct rbd_device *rbd_dev); | |
516 | static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev); | |
517 | static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev); | |
518 | static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, | |
519 | u64 snap_id); | |
520 | static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id, | |
521 | u8 *order, u64 *snap_size); | |
522 | static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id, | |
523 | u64 *snap_features); | |
524 | static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name); | |
525 | ||
526 | static int rbd_open(struct block_device *bdev, fmode_t mode) | |
527 | { | |
528 | struct rbd_device *rbd_dev = bdev->bd_disk->private_data; | |
529 | bool removing = false; | |
530 | ||
531 | if ((mode & FMODE_WRITE) && rbd_dev->mapping.read_only) | |
532 | return -EROFS; | |
533 | ||
534 | spin_lock_irq(&rbd_dev->lock); | |
535 | if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) | |
536 | removing = true; | |
537 | else | |
538 | rbd_dev->open_count++; | |
539 | spin_unlock_irq(&rbd_dev->lock); | |
540 | if (removing) | |
541 | return -ENOENT; | |
542 | ||
543 | (void) get_device(&rbd_dev->dev); | |
544 | set_device_ro(bdev, rbd_dev->mapping.read_only); | |
545 | ||
546 | return 0; | |
547 | } | |
548 | ||
549 | static void rbd_release(struct gendisk *disk, fmode_t mode) | |
550 | { | |
551 | struct rbd_device *rbd_dev = disk->private_data; | |
552 | unsigned long open_count_before; | |
553 | ||
554 | spin_lock_irq(&rbd_dev->lock); | |
555 | open_count_before = rbd_dev->open_count--; | |
556 | spin_unlock_irq(&rbd_dev->lock); | |
557 | rbd_assert(open_count_before > 0); | |
558 | ||
559 | put_device(&rbd_dev->dev); | |
560 | } | |
561 | ||
562 | static const struct block_device_operations rbd_bd_ops = { | |
563 | .owner = THIS_MODULE, | |
564 | .open = rbd_open, | |
565 | .release = rbd_release, | |
566 | }; | |
567 | ||
568 | /* | |
569 | * Initialize an rbd client instance. Success or not, this function | |
570 | * consumes ceph_opts. Caller holds client_mutex. | |
571 | */ | |
572 | static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts) | |
573 | { | |
574 | struct rbd_client *rbdc; | |
575 | int ret = -ENOMEM; | |
576 | ||
577 | dout("%s:\n", __func__); | |
578 | rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL); | |
579 | if (!rbdc) | |
580 | goto out_opt; | |
581 | ||
582 | kref_init(&rbdc->kref); | |
583 | INIT_LIST_HEAD(&rbdc->node); | |
584 | ||
585 | rbdc->client = ceph_create_client(ceph_opts, rbdc, 0, 0); | |
586 | if (IS_ERR(rbdc->client)) | |
587 | goto out_rbdc; | |
588 | ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */ | |
589 | ||
590 | ret = ceph_open_session(rbdc->client); | |
591 | if (ret < 0) | |
592 | goto out_client; | |
593 | ||
594 | spin_lock(&rbd_client_list_lock); | |
595 | list_add_tail(&rbdc->node, &rbd_client_list); | |
596 | spin_unlock(&rbd_client_list_lock); | |
597 | ||
598 | dout("%s: rbdc %p\n", __func__, rbdc); | |
599 | ||
600 | return rbdc; | |
601 | out_client: | |
602 | ceph_destroy_client(rbdc->client); | |
603 | out_rbdc: | |
604 | kfree(rbdc); | |
605 | out_opt: | |
606 | if (ceph_opts) | |
607 | ceph_destroy_options(ceph_opts); | |
608 | dout("%s: error %d\n", __func__, ret); | |
609 | ||
610 | return ERR_PTR(ret); | |
611 | } | |
612 | ||
613 | static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc) | |
614 | { | |
615 | kref_get(&rbdc->kref); | |
616 | ||
617 | return rbdc; | |
618 | } | |
619 | ||
620 | /* | |
621 | * Find a ceph client with specific addr and configuration. If | |
622 | * found, bump its reference count. | |
623 | */ | |
624 | static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts) | |
625 | { | |
626 | struct rbd_client *client_node; | |
627 | bool found = false; | |
628 | ||
629 | if (ceph_opts->flags & CEPH_OPT_NOSHARE) | |
630 | return NULL; | |
631 | ||
632 | spin_lock(&rbd_client_list_lock); | |
633 | list_for_each_entry(client_node, &rbd_client_list, node) { | |
634 | if (!ceph_compare_options(ceph_opts, client_node->client)) { | |
635 | __rbd_get_client(client_node); | |
636 | ||
637 | found = true; | |
638 | break; | |
639 | } | |
640 | } | |
641 | spin_unlock(&rbd_client_list_lock); | |
642 | ||
643 | return found ? client_node : NULL; | |
644 | } | |
645 | ||
646 | /* | |
647 | * mount options | |
648 | */ | |
649 | enum { | |
650 | Opt_last_int, | |
651 | /* int args above */ | |
652 | Opt_last_string, | |
653 | /* string args above */ | |
654 | Opt_read_only, | |
655 | Opt_read_write, | |
656 | /* Boolean args above */ | |
657 | Opt_last_bool, | |
658 | }; | |
659 | ||
660 | static match_table_t rbd_opts_tokens = { | |
661 | /* int args above */ | |
662 | /* string args above */ | |
663 | {Opt_read_only, "read_only"}, | |
664 | {Opt_read_only, "ro"}, /* Alternate spelling */ | |
665 | {Opt_read_write, "read_write"}, | |
666 | {Opt_read_write, "rw"}, /* Alternate spelling */ | |
667 | /* Boolean args above */ | |
668 | {-1, NULL} | |
669 | }; | |
670 | ||
671 | struct rbd_options { | |
672 | bool read_only; | |
673 | }; | |
674 | ||
675 | #define RBD_READ_ONLY_DEFAULT false | |
676 | ||
677 | static int parse_rbd_opts_token(char *c, void *private) | |
678 | { | |
679 | struct rbd_options *rbd_opts = private; | |
680 | substring_t argstr[MAX_OPT_ARGS]; | |
681 | int token, intval, ret; | |
682 | ||
683 | token = match_token(c, rbd_opts_tokens, argstr); | |
684 | if (token < 0) | |
685 | return -EINVAL; | |
686 | ||
687 | if (token < Opt_last_int) { | |
688 | ret = match_int(&argstr[0], &intval); | |
689 | if (ret < 0) { | |
690 | pr_err("bad mount option arg (not int) " | |
691 | "at '%s'\n", c); | |
692 | return ret; | |
693 | } | |
694 | dout("got int token %d val %d\n", token, intval); | |
695 | } else if (token > Opt_last_int && token < Opt_last_string) { | |
696 | dout("got string token %d val %s\n", token, | |
697 | argstr[0].from); | |
698 | } else if (token > Opt_last_string && token < Opt_last_bool) { | |
699 | dout("got Boolean token %d\n", token); | |
700 | } else { | |
701 | dout("got token %d\n", token); | |
702 | } | |
703 | ||
704 | switch (token) { | |
705 | case Opt_read_only: | |
706 | rbd_opts->read_only = true; | |
707 | break; | |
708 | case Opt_read_write: | |
709 | rbd_opts->read_only = false; | |
710 | break; | |
711 | default: | |
712 | rbd_assert(false); | |
713 | break; | |
714 | } | |
715 | return 0; | |
716 | } | |
717 | ||
718 | /* | |
719 | * Get a ceph client with specific addr and configuration, if one does | |
720 | * not exist create it. Either way, ceph_opts is consumed by this | |
721 | * function. | |
722 | */ | |
723 | static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts) | |
724 | { | |
725 | struct rbd_client *rbdc; | |
726 | ||
727 | mutex_lock_nested(&client_mutex, SINGLE_DEPTH_NESTING); | |
728 | rbdc = rbd_client_find(ceph_opts); | |
729 | if (rbdc) /* using an existing client */ | |
730 | ceph_destroy_options(ceph_opts); | |
731 | else | |
732 | rbdc = rbd_client_create(ceph_opts); | |
733 | mutex_unlock(&client_mutex); | |
734 | ||
735 | return rbdc; | |
736 | } | |
737 | ||
738 | /* | |
739 | * Destroy ceph client | |
740 | * | |
741 | * Caller must hold rbd_client_list_lock. | |
742 | */ | |
743 | static void rbd_client_release(struct kref *kref) | |
744 | { | |
745 | struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref); | |
746 | ||
747 | dout("%s: rbdc %p\n", __func__, rbdc); | |
748 | spin_lock(&rbd_client_list_lock); | |
749 | list_del(&rbdc->node); | |
750 | spin_unlock(&rbd_client_list_lock); | |
751 | ||
752 | ceph_destroy_client(rbdc->client); | |
753 | kfree(rbdc); | |
754 | } | |
755 | ||
756 | /* | |
757 | * Drop reference to ceph client node. If it's not referenced anymore, release | |
758 | * it. | |
759 | */ | |
760 | static void rbd_put_client(struct rbd_client *rbdc) | |
761 | { | |
762 | if (rbdc) | |
763 | kref_put(&rbdc->kref, rbd_client_release); | |
764 | } | |
765 | ||
766 | static bool rbd_image_format_valid(u32 image_format) | |
767 | { | |
768 | return image_format == 1 || image_format == 2; | |
769 | } | |
770 | ||
771 | static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk) | |
772 | { | |
773 | size_t size; | |
774 | u32 snap_count; | |
775 | ||
776 | /* The header has to start with the magic rbd header text */ | |
777 | if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT))) | |
778 | return false; | |
779 | ||
780 | /* The bio layer requires at least sector-sized I/O */ | |
781 | ||
782 | if (ondisk->options.order < SECTOR_SHIFT) | |
783 | return false; | |
784 | ||
785 | /* If we use u64 in a few spots we may be able to loosen this */ | |
786 | ||
787 | if (ondisk->options.order > 8 * sizeof (int) - 1) | |
788 | return false; | |
789 | ||
790 | /* | |
791 | * The size of a snapshot header has to fit in a size_t, and | |
792 | * that limits the number of snapshots. | |
793 | */ | |
794 | snap_count = le32_to_cpu(ondisk->snap_count); | |
795 | size = SIZE_MAX - sizeof (struct ceph_snap_context); | |
796 | if (snap_count > size / sizeof (__le64)) | |
797 | return false; | |
798 | ||
799 | /* | |
800 | * Not only that, but the size of the entire the snapshot | |
801 | * header must also be representable in a size_t. | |
802 | */ | |
803 | size -= snap_count * sizeof (__le64); | |
804 | if ((u64) size < le64_to_cpu(ondisk->snap_names_len)) | |
805 | return false; | |
806 | ||
807 | return true; | |
808 | } | |
809 | ||
810 | /* | |
811 | * Fill an rbd image header with information from the given format 1 | |
812 | * on-disk header. | |
813 | */ | |
814 | static int rbd_header_from_disk(struct rbd_device *rbd_dev, | |
815 | struct rbd_image_header_ondisk *ondisk) | |
816 | { | |
817 | struct rbd_image_header *header = &rbd_dev->header; | |
818 | bool first_time = header->object_prefix == NULL; | |
819 | struct ceph_snap_context *snapc; | |
820 | char *object_prefix = NULL; | |
821 | char *snap_names = NULL; | |
822 | u64 *snap_sizes = NULL; | |
823 | u32 snap_count; | |
824 | size_t size; | |
825 | int ret = -ENOMEM; | |
826 | u32 i; | |
827 | ||
828 | /* Allocate this now to avoid having to handle failure below */ | |
829 | ||
830 | if (first_time) { | |
831 | size_t len; | |
832 | ||
833 | len = strnlen(ondisk->object_prefix, | |
834 | sizeof (ondisk->object_prefix)); | |
835 | object_prefix = kmalloc(len + 1, GFP_KERNEL); | |
836 | if (!object_prefix) | |
837 | return -ENOMEM; | |
838 | memcpy(object_prefix, ondisk->object_prefix, len); | |
839 | object_prefix[len] = '\0'; | |
840 | } | |
841 | ||
842 | /* Allocate the snapshot context and fill it in */ | |
843 | ||
844 | snap_count = le32_to_cpu(ondisk->snap_count); | |
845 | snapc = ceph_create_snap_context(snap_count, GFP_KERNEL); | |
846 | if (!snapc) | |
847 | goto out_err; | |
848 | snapc->seq = le64_to_cpu(ondisk->snap_seq); | |
849 | if (snap_count) { | |
850 | struct rbd_image_snap_ondisk *snaps; | |
851 | u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len); | |
852 | ||
853 | /* We'll keep a copy of the snapshot names... */ | |
854 | ||
855 | if (snap_names_len > (u64)SIZE_MAX) | |
856 | goto out_2big; | |
857 | snap_names = kmalloc(snap_names_len, GFP_KERNEL); | |
858 | if (!snap_names) | |
859 | goto out_err; | |
860 | ||
861 | /* ...as well as the array of their sizes. */ | |
862 | ||
863 | size = snap_count * sizeof (*header->snap_sizes); | |
864 | snap_sizes = kmalloc(size, GFP_KERNEL); | |
865 | if (!snap_sizes) | |
866 | goto out_err; | |
867 | ||
868 | /* | |
869 | * Copy the names, and fill in each snapshot's id | |
870 | * and size. | |
871 | * | |
872 | * Note that rbd_dev_v1_header_info() guarantees the | |
873 | * ondisk buffer we're working with has | |
874 | * snap_names_len bytes beyond the end of the | |
875 | * snapshot id array, this memcpy() is safe. | |
876 | */ | |
877 | memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len); | |
878 | snaps = ondisk->snaps; | |
879 | for (i = 0; i < snap_count; i++) { | |
880 | snapc->snaps[i] = le64_to_cpu(snaps[i].id); | |
881 | snap_sizes[i] = le64_to_cpu(snaps[i].image_size); | |
882 | } | |
883 | } | |
884 | ||
885 | /* We won't fail any more, fill in the header */ | |
886 | ||
887 | if (first_time) { | |
888 | header->object_prefix = object_prefix; | |
889 | header->obj_order = ondisk->options.order; | |
890 | header->crypt_type = ondisk->options.crypt_type; | |
891 | header->comp_type = ondisk->options.comp_type; | |
892 | /* The rest aren't used for format 1 images */ | |
893 | header->stripe_unit = 0; | |
894 | header->stripe_count = 0; | |
895 | header->features = 0; | |
896 | } else { | |
897 | ceph_put_snap_context(header->snapc); | |
898 | kfree(header->snap_names); | |
899 | kfree(header->snap_sizes); | |
900 | } | |
901 | ||
902 | /* The remaining fields always get updated (when we refresh) */ | |
903 | ||
904 | header->image_size = le64_to_cpu(ondisk->image_size); | |
905 | header->snapc = snapc; | |
906 | header->snap_names = snap_names; | |
907 | header->snap_sizes = snap_sizes; | |
908 | ||
909 | /* Make sure mapping size is consistent with header info */ | |
910 | ||
911 | if (rbd_dev->spec->snap_id == CEPH_NOSNAP || first_time) | |
912 | if (rbd_dev->mapping.size != header->image_size) | |
913 | rbd_dev->mapping.size = header->image_size; | |
914 | ||
915 | return 0; | |
916 | out_2big: | |
917 | ret = -EIO; | |
918 | out_err: | |
919 | kfree(snap_sizes); | |
920 | kfree(snap_names); | |
921 | ceph_put_snap_context(snapc); | |
922 | kfree(object_prefix); | |
923 | ||
924 | return ret; | |
925 | } | |
926 | ||
927 | static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which) | |
928 | { | |
929 | const char *snap_name; | |
930 | ||
931 | rbd_assert(which < rbd_dev->header.snapc->num_snaps); | |
932 | ||
933 | /* Skip over names until we find the one we are looking for */ | |
934 | ||
935 | snap_name = rbd_dev->header.snap_names; | |
936 | while (which--) | |
937 | snap_name += strlen(snap_name) + 1; | |
938 | ||
939 | return kstrdup(snap_name, GFP_KERNEL); | |
940 | } | |
941 | ||
942 | /* | |
943 | * Snapshot id comparison function for use with qsort()/bsearch(). | |
944 | * Note that result is for snapshots in *descending* order. | |
945 | */ | |
946 | static int snapid_compare_reverse(const void *s1, const void *s2) | |
947 | { | |
948 | u64 snap_id1 = *(u64 *)s1; | |
949 | u64 snap_id2 = *(u64 *)s2; | |
950 | ||
951 | if (snap_id1 < snap_id2) | |
952 | return 1; | |
953 | return snap_id1 == snap_id2 ? 0 : -1; | |
954 | } | |
955 | ||
956 | /* | |
957 | * Search a snapshot context to see if the given snapshot id is | |
958 | * present. | |
959 | * | |
960 | * Returns the position of the snapshot id in the array if it's found, | |
961 | * or BAD_SNAP_INDEX otherwise. | |
962 | * | |
963 | * Note: The snapshot array is in kept sorted (by the osd) in | |
964 | * reverse order, highest snapshot id first. | |
965 | */ | |
966 | static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id) | |
967 | { | |
968 | struct ceph_snap_context *snapc = rbd_dev->header.snapc; | |
969 | u64 *found; | |
970 | ||
971 | found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps, | |
972 | sizeof (snap_id), snapid_compare_reverse); | |
973 | ||
974 | return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX; | |
975 | } | |
976 | ||
977 | static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, | |
978 | u64 snap_id) | |
979 | { | |
980 | u32 which; | |
981 | const char *snap_name; | |
982 | ||
983 | which = rbd_dev_snap_index(rbd_dev, snap_id); | |
984 | if (which == BAD_SNAP_INDEX) | |
985 | return ERR_PTR(-ENOENT); | |
986 | ||
987 | snap_name = _rbd_dev_v1_snap_name(rbd_dev, which); | |
988 | return snap_name ? snap_name : ERR_PTR(-ENOMEM); | |
989 | } | |
990 | ||
991 | static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id) | |
992 | { | |
993 | if (snap_id == CEPH_NOSNAP) | |
994 | return RBD_SNAP_HEAD_NAME; | |
995 | ||
996 | rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); | |
997 | if (rbd_dev->image_format == 1) | |
998 | return rbd_dev_v1_snap_name(rbd_dev, snap_id); | |
999 | ||
1000 | return rbd_dev_v2_snap_name(rbd_dev, snap_id); | |
1001 | } | |
1002 | ||
1003 | static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id, | |
1004 | u64 *snap_size) | |
1005 | { | |
1006 | rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); | |
1007 | if (snap_id == CEPH_NOSNAP) { | |
1008 | *snap_size = rbd_dev->header.image_size; | |
1009 | } else if (rbd_dev->image_format == 1) { | |
1010 | u32 which; | |
1011 | ||
1012 | which = rbd_dev_snap_index(rbd_dev, snap_id); | |
1013 | if (which == BAD_SNAP_INDEX) | |
1014 | return -ENOENT; | |
1015 | ||
1016 | *snap_size = rbd_dev->header.snap_sizes[which]; | |
1017 | } else { | |
1018 | u64 size = 0; | |
1019 | int ret; | |
1020 | ||
1021 | ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size); | |
1022 | if (ret) | |
1023 | return ret; | |
1024 | ||
1025 | *snap_size = size; | |
1026 | } | |
1027 | return 0; | |
1028 | } | |
1029 | ||
1030 | static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id, | |
1031 | u64 *snap_features) | |
1032 | { | |
1033 | rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); | |
1034 | if (snap_id == CEPH_NOSNAP) { | |
1035 | *snap_features = rbd_dev->header.features; | |
1036 | } else if (rbd_dev->image_format == 1) { | |
1037 | *snap_features = 0; /* No features for format 1 */ | |
1038 | } else { | |
1039 | u64 features = 0; | |
1040 | int ret; | |
1041 | ||
1042 | ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features); | |
1043 | if (ret) | |
1044 | return ret; | |
1045 | ||
1046 | *snap_features = features; | |
1047 | } | |
1048 | return 0; | |
1049 | } | |
1050 | ||
1051 | static int rbd_dev_mapping_set(struct rbd_device *rbd_dev) | |
1052 | { | |
1053 | u64 snap_id = rbd_dev->spec->snap_id; | |
1054 | u64 size = 0; | |
1055 | u64 features = 0; | |
1056 | int ret; | |
1057 | ||
1058 | ret = rbd_snap_size(rbd_dev, snap_id, &size); | |
1059 | if (ret) | |
1060 | return ret; | |
1061 | ret = rbd_snap_features(rbd_dev, snap_id, &features); | |
1062 | if (ret) | |
1063 | return ret; | |
1064 | ||
1065 | rbd_dev->mapping.size = size; | |
1066 | rbd_dev->mapping.features = features; | |
1067 | ||
1068 | return 0; | |
1069 | } | |
1070 | ||
1071 | static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev) | |
1072 | { | |
1073 | rbd_dev->mapping.size = 0; | |
1074 | rbd_dev->mapping.features = 0; | |
1075 | } | |
1076 | ||
1077 | static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset) | |
1078 | { | |
1079 | char *name; | |
1080 | u64 segment; | |
1081 | int ret; | |
1082 | char *name_format; | |
1083 | ||
1084 | name = kmem_cache_alloc(rbd_segment_name_cache, GFP_NOIO); | |
1085 | if (!name) | |
1086 | return NULL; | |
1087 | segment = offset >> rbd_dev->header.obj_order; | |
1088 | name_format = "%s.%012llx"; | |
1089 | if (rbd_dev->image_format == 2) | |
1090 | name_format = "%s.%016llx"; | |
1091 | ret = snprintf(name, CEPH_MAX_OID_NAME_LEN + 1, name_format, | |
1092 | rbd_dev->header.object_prefix, segment); | |
1093 | if (ret < 0 || ret > CEPH_MAX_OID_NAME_LEN) { | |
1094 | pr_err("error formatting segment name for #%llu (%d)\n", | |
1095 | segment, ret); | |
1096 | kfree(name); | |
1097 | name = NULL; | |
1098 | } | |
1099 | ||
1100 | return name; | |
1101 | } | |
1102 | ||
1103 | static void rbd_segment_name_free(const char *name) | |
1104 | { | |
1105 | /* The explicit cast here is needed to drop the const qualifier */ | |
1106 | ||
1107 | kmem_cache_free(rbd_segment_name_cache, (void *)name); | |
1108 | } | |
1109 | ||
1110 | static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset) | |
1111 | { | |
1112 | u64 segment_size = (u64) 1 << rbd_dev->header.obj_order; | |
1113 | ||
1114 | return offset & (segment_size - 1); | |
1115 | } | |
1116 | ||
1117 | static u64 rbd_segment_length(struct rbd_device *rbd_dev, | |
1118 | u64 offset, u64 length) | |
1119 | { | |
1120 | u64 segment_size = (u64) 1 << rbd_dev->header.obj_order; | |
1121 | ||
1122 | offset &= segment_size - 1; | |
1123 | ||
1124 | rbd_assert(length <= U64_MAX - offset); | |
1125 | if (offset + length > segment_size) | |
1126 | length = segment_size - offset; | |
1127 | ||
1128 | return length; | |
1129 | } | |
1130 | ||
1131 | /* | |
1132 | * returns the size of an object in the image | |
1133 | */ | |
1134 | static u64 rbd_obj_bytes(struct rbd_image_header *header) | |
1135 | { | |
1136 | return 1 << header->obj_order; | |
1137 | } | |
1138 | ||
1139 | /* | |
1140 | * bio helpers | |
1141 | */ | |
1142 | ||
1143 | static void bio_chain_put(struct bio *chain) | |
1144 | { | |
1145 | struct bio *tmp; | |
1146 | ||
1147 | while (chain) { | |
1148 | tmp = chain; | |
1149 | chain = chain->bi_next; | |
1150 | bio_put(tmp); | |
1151 | } | |
1152 | } | |
1153 | ||
1154 | /* | |
1155 | * zeros a bio chain, starting at specific offset | |
1156 | */ | |
1157 | static void zero_bio_chain(struct bio *chain, int start_ofs) | |
1158 | { | |
1159 | struct bio_vec bv; | |
1160 | struct bvec_iter iter; | |
1161 | unsigned long flags; | |
1162 | void *buf; | |
1163 | int pos = 0; | |
1164 | ||
1165 | while (chain) { | |
1166 | bio_for_each_segment(bv, chain, iter) { | |
1167 | if (pos + bv.bv_len > start_ofs) { | |
1168 | int remainder = max(start_ofs - pos, 0); | |
1169 | buf = bvec_kmap_irq(&bv, &flags); | |
1170 | memset(buf + remainder, 0, | |
1171 | bv.bv_len - remainder); | |
1172 | flush_dcache_page(bv.bv_page); | |
1173 | bvec_kunmap_irq(buf, &flags); | |
1174 | } | |
1175 | pos += bv.bv_len; | |
1176 | } | |
1177 | ||
1178 | chain = chain->bi_next; | |
1179 | } | |
1180 | } | |
1181 | ||
1182 | /* | |
1183 | * similar to zero_bio_chain(), zeros data defined by a page array, | |
1184 | * starting at the given byte offset from the start of the array and | |
1185 | * continuing up to the given end offset. The pages array is | |
1186 | * assumed to be big enough to hold all bytes up to the end. | |
1187 | */ | |
1188 | static void zero_pages(struct page **pages, u64 offset, u64 end) | |
1189 | { | |
1190 | struct page **page = &pages[offset >> PAGE_SHIFT]; | |
1191 | ||
1192 | rbd_assert(end > offset); | |
1193 | rbd_assert(end - offset <= (u64)SIZE_MAX); | |
1194 | while (offset < end) { | |
1195 | size_t page_offset; | |
1196 | size_t length; | |
1197 | unsigned long flags; | |
1198 | void *kaddr; | |
1199 | ||
1200 | page_offset = offset & ~PAGE_MASK; | |
1201 | length = min_t(size_t, PAGE_SIZE - page_offset, end - offset); | |
1202 | local_irq_save(flags); | |
1203 | kaddr = kmap_atomic(*page); | |
1204 | memset(kaddr + page_offset, 0, length); | |
1205 | flush_dcache_page(*page); | |
1206 | kunmap_atomic(kaddr); | |
1207 | local_irq_restore(flags); | |
1208 | ||
1209 | offset += length; | |
1210 | page++; | |
1211 | } | |
1212 | } | |
1213 | ||
1214 | /* | |
1215 | * Clone a portion of a bio, starting at the given byte offset | |
1216 | * and continuing for the number of bytes indicated. | |
1217 | */ | |
1218 | static struct bio *bio_clone_range(struct bio *bio_src, | |
1219 | unsigned int offset, | |
1220 | unsigned int len, | |
1221 | gfp_t gfpmask) | |
1222 | { | |
1223 | struct bio *bio; | |
1224 | ||
1225 | bio = bio_clone(bio_src, gfpmask); | |
1226 | if (!bio) | |
1227 | return NULL; /* ENOMEM */ | |
1228 | ||
1229 | bio_advance(bio, offset); | |
1230 | bio->bi_iter.bi_size = len; | |
1231 | ||
1232 | return bio; | |
1233 | } | |
1234 | ||
1235 | /* | |
1236 | * Clone a portion of a bio chain, starting at the given byte offset | |
1237 | * into the first bio in the source chain and continuing for the | |
1238 | * number of bytes indicated. The result is another bio chain of | |
1239 | * exactly the given length, or a null pointer on error. | |
1240 | * | |
1241 | * The bio_src and offset parameters are both in-out. On entry they | |
1242 | * refer to the first source bio and the offset into that bio where | |
1243 | * the start of data to be cloned is located. | |
1244 | * | |
1245 | * On return, bio_src is updated to refer to the bio in the source | |
1246 | * chain that contains first un-cloned byte, and *offset will | |
1247 | * contain the offset of that byte within that bio. | |
1248 | */ | |
1249 | static struct bio *bio_chain_clone_range(struct bio **bio_src, | |
1250 | unsigned int *offset, | |
1251 | unsigned int len, | |
1252 | gfp_t gfpmask) | |
1253 | { | |
1254 | struct bio *bi = *bio_src; | |
1255 | unsigned int off = *offset; | |
1256 | struct bio *chain = NULL; | |
1257 | struct bio **end; | |
1258 | ||
1259 | /* Build up a chain of clone bios up to the limit */ | |
1260 | ||
1261 | if (!bi || off >= bi->bi_iter.bi_size || !len) | |
1262 | return NULL; /* Nothing to clone */ | |
1263 | ||
1264 | end = &chain; | |
1265 | while (len) { | |
1266 | unsigned int bi_size; | |
1267 | struct bio *bio; | |
1268 | ||
1269 | if (!bi) { | |
1270 | rbd_warn(NULL, "bio_chain exhausted with %u left", len); | |
1271 | goto out_err; /* EINVAL; ran out of bio's */ | |
1272 | } | |
1273 | bi_size = min_t(unsigned int, bi->bi_iter.bi_size - off, len); | |
1274 | bio = bio_clone_range(bi, off, bi_size, gfpmask); | |
1275 | if (!bio) | |
1276 | goto out_err; /* ENOMEM */ | |
1277 | ||
1278 | *end = bio; | |
1279 | end = &bio->bi_next; | |
1280 | ||
1281 | off += bi_size; | |
1282 | if (off == bi->bi_iter.bi_size) { | |
1283 | bi = bi->bi_next; | |
1284 | off = 0; | |
1285 | } | |
1286 | len -= bi_size; | |
1287 | } | |
1288 | *bio_src = bi; | |
1289 | *offset = off; | |
1290 | ||
1291 | return chain; | |
1292 | out_err: | |
1293 | bio_chain_put(chain); | |
1294 | ||
1295 | return NULL; | |
1296 | } | |
1297 | ||
1298 | /* | |
1299 | * The default/initial value for all object request flags is 0. For | |
1300 | * each flag, once its value is set to 1 it is never reset to 0 | |
1301 | * again. | |
1302 | */ | |
1303 | static void obj_request_img_data_set(struct rbd_obj_request *obj_request) | |
1304 | { | |
1305 | if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) { | |
1306 | struct rbd_device *rbd_dev; | |
1307 | ||
1308 | rbd_dev = obj_request->img_request->rbd_dev; | |
1309 | rbd_warn(rbd_dev, "obj_request %p already marked img_data\n", | |
1310 | obj_request); | |
1311 | } | |
1312 | } | |
1313 | ||
1314 | static bool obj_request_img_data_test(struct rbd_obj_request *obj_request) | |
1315 | { | |
1316 | smp_mb(); | |
1317 | return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0; | |
1318 | } | |
1319 | ||
1320 | static void obj_request_done_set(struct rbd_obj_request *obj_request) | |
1321 | { | |
1322 | if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) { | |
1323 | struct rbd_device *rbd_dev = NULL; | |
1324 | ||
1325 | if (obj_request_img_data_test(obj_request)) | |
1326 | rbd_dev = obj_request->img_request->rbd_dev; | |
1327 | rbd_warn(rbd_dev, "obj_request %p already marked done\n", | |
1328 | obj_request); | |
1329 | } | |
1330 | } | |
1331 | ||
1332 | static bool obj_request_done_test(struct rbd_obj_request *obj_request) | |
1333 | { | |
1334 | smp_mb(); | |
1335 | return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0; | |
1336 | } | |
1337 | ||
1338 | /* | |
1339 | * This sets the KNOWN flag after (possibly) setting the EXISTS | |
1340 | * flag. The latter is set based on the "exists" value provided. | |
1341 | * | |
1342 | * Note that for our purposes once an object exists it never goes | |
1343 | * away again. It's possible that the response from two existence | |
1344 | * checks are separated by the creation of the target object, and | |
1345 | * the first ("doesn't exist") response arrives *after* the second | |
1346 | * ("does exist"). In that case we ignore the second one. | |
1347 | */ | |
1348 | static void obj_request_existence_set(struct rbd_obj_request *obj_request, | |
1349 | bool exists) | |
1350 | { | |
1351 | if (exists) | |
1352 | set_bit(OBJ_REQ_EXISTS, &obj_request->flags); | |
1353 | set_bit(OBJ_REQ_KNOWN, &obj_request->flags); | |
1354 | smp_mb(); | |
1355 | } | |
1356 | ||
1357 | static bool obj_request_known_test(struct rbd_obj_request *obj_request) | |
1358 | { | |
1359 | smp_mb(); | |
1360 | return test_bit(OBJ_REQ_KNOWN, &obj_request->flags) != 0; | |
1361 | } | |
1362 | ||
1363 | static bool obj_request_exists_test(struct rbd_obj_request *obj_request) | |
1364 | { | |
1365 | smp_mb(); | |
1366 | return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0; | |
1367 | } | |
1368 | ||
1369 | static void rbd_obj_request_get(struct rbd_obj_request *obj_request) | |
1370 | { | |
1371 | dout("%s: obj %p (was %d)\n", __func__, obj_request, | |
1372 | atomic_read(&obj_request->kref.refcount)); | |
1373 | kref_get(&obj_request->kref); | |
1374 | } | |
1375 | ||
1376 | static void rbd_obj_request_destroy(struct kref *kref); | |
1377 | static void rbd_obj_request_put(struct rbd_obj_request *obj_request) | |
1378 | { | |
1379 | rbd_assert(obj_request != NULL); | |
1380 | dout("%s: obj %p (was %d)\n", __func__, obj_request, | |
1381 | atomic_read(&obj_request->kref.refcount)); | |
1382 | kref_put(&obj_request->kref, rbd_obj_request_destroy); | |
1383 | } | |
1384 | ||
1385 | static bool img_request_child_test(struct rbd_img_request *img_request); | |
1386 | static void rbd_parent_request_destroy(struct kref *kref); | |
1387 | static void rbd_img_request_destroy(struct kref *kref); | |
1388 | static void rbd_img_request_put(struct rbd_img_request *img_request) | |
1389 | { | |
1390 | rbd_assert(img_request != NULL); | |
1391 | dout("%s: img %p (was %d)\n", __func__, img_request, | |
1392 | atomic_read(&img_request->kref.refcount)); | |
1393 | if (img_request_child_test(img_request)) | |
1394 | kref_put(&img_request->kref, rbd_parent_request_destroy); | |
1395 | else | |
1396 | kref_put(&img_request->kref, rbd_img_request_destroy); | |
1397 | } | |
1398 | ||
1399 | static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request, | |
1400 | struct rbd_obj_request *obj_request) | |
1401 | { | |
1402 | rbd_assert(obj_request->img_request == NULL); | |
1403 | ||
1404 | /* Image request now owns object's original reference */ | |
1405 | obj_request->img_request = img_request; | |
1406 | obj_request->which = img_request->obj_request_count; | |
1407 | rbd_assert(!obj_request_img_data_test(obj_request)); | |
1408 | obj_request_img_data_set(obj_request); | |
1409 | rbd_assert(obj_request->which != BAD_WHICH); | |
1410 | img_request->obj_request_count++; | |
1411 | list_add_tail(&obj_request->links, &img_request->obj_requests); | |
1412 | dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request, | |
1413 | obj_request->which); | |
1414 | } | |
1415 | ||
1416 | static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request, | |
1417 | struct rbd_obj_request *obj_request) | |
1418 | { | |
1419 | rbd_assert(obj_request->which != BAD_WHICH); | |
1420 | ||
1421 | dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request, | |
1422 | obj_request->which); | |
1423 | list_del(&obj_request->links); | |
1424 | rbd_assert(img_request->obj_request_count > 0); | |
1425 | img_request->obj_request_count--; | |
1426 | rbd_assert(obj_request->which == img_request->obj_request_count); | |
1427 | obj_request->which = BAD_WHICH; | |
1428 | rbd_assert(obj_request_img_data_test(obj_request)); | |
1429 | rbd_assert(obj_request->img_request == img_request); | |
1430 | obj_request->img_request = NULL; | |
1431 | obj_request->callback = NULL; | |
1432 | rbd_obj_request_put(obj_request); | |
1433 | } | |
1434 | ||
1435 | static bool obj_request_type_valid(enum obj_request_type type) | |
1436 | { | |
1437 | switch (type) { | |
1438 | case OBJ_REQUEST_NODATA: | |
1439 | case OBJ_REQUEST_BIO: | |
1440 | case OBJ_REQUEST_PAGES: | |
1441 | return true; | |
1442 | default: | |
1443 | return false; | |
1444 | } | |
1445 | } | |
1446 | ||
1447 | static int rbd_obj_request_submit(struct ceph_osd_client *osdc, | |
1448 | struct rbd_obj_request *obj_request) | |
1449 | { | |
1450 | dout("%s: osdc %p obj %p\n", __func__, osdc, obj_request); | |
1451 | ||
1452 | return ceph_osdc_start_request(osdc, obj_request->osd_req, false); | |
1453 | } | |
1454 | ||
1455 | static void rbd_img_request_complete(struct rbd_img_request *img_request) | |
1456 | { | |
1457 | ||
1458 | dout("%s: img %p\n", __func__, img_request); | |
1459 | ||
1460 | /* | |
1461 | * If no error occurred, compute the aggregate transfer | |
1462 | * count for the image request. We could instead use | |
1463 | * atomic64_cmpxchg() to update it as each object request | |
1464 | * completes; not clear which way is better off hand. | |
1465 | */ | |
1466 | if (!img_request->result) { | |
1467 | struct rbd_obj_request *obj_request; | |
1468 | u64 xferred = 0; | |
1469 | ||
1470 | for_each_obj_request(img_request, obj_request) | |
1471 | xferred += obj_request->xferred; | |
1472 | img_request->xferred = xferred; | |
1473 | } | |
1474 | ||
1475 | if (img_request->callback) | |
1476 | img_request->callback(img_request); | |
1477 | else | |
1478 | rbd_img_request_put(img_request); | |
1479 | } | |
1480 | ||
1481 | /* Caller is responsible for rbd_obj_request_destroy(obj_request) */ | |
1482 | ||
1483 | static int rbd_obj_request_wait(struct rbd_obj_request *obj_request) | |
1484 | { | |
1485 | dout("%s: obj %p\n", __func__, obj_request); | |
1486 | ||
1487 | return wait_for_completion_interruptible(&obj_request->completion); | |
1488 | } | |
1489 | ||
1490 | /* | |
1491 | * The default/initial value for all image request flags is 0. Each | |
1492 | * is conditionally set to 1 at image request initialization time | |
1493 | * and currently never change thereafter. | |
1494 | */ | |
1495 | static void img_request_write_set(struct rbd_img_request *img_request) | |
1496 | { | |
1497 | set_bit(IMG_REQ_WRITE, &img_request->flags); | |
1498 | smp_mb(); | |
1499 | } | |
1500 | ||
1501 | static bool img_request_write_test(struct rbd_img_request *img_request) | |
1502 | { | |
1503 | smp_mb(); | |
1504 | return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0; | |
1505 | } | |
1506 | ||
1507 | static void img_request_child_set(struct rbd_img_request *img_request) | |
1508 | { | |
1509 | set_bit(IMG_REQ_CHILD, &img_request->flags); | |
1510 | smp_mb(); | |
1511 | } | |
1512 | ||
1513 | static void img_request_child_clear(struct rbd_img_request *img_request) | |
1514 | { | |
1515 | clear_bit(IMG_REQ_CHILD, &img_request->flags); | |
1516 | smp_mb(); | |
1517 | } | |
1518 | ||
1519 | static bool img_request_child_test(struct rbd_img_request *img_request) | |
1520 | { | |
1521 | smp_mb(); | |
1522 | return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0; | |
1523 | } | |
1524 | ||
1525 | static void img_request_layered_set(struct rbd_img_request *img_request) | |
1526 | { | |
1527 | set_bit(IMG_REQ_LAYERED, &img_request->flags); | |
1528 | smp_mb(); | |
1529 | } | |
1530 | ||
1531 | static void img_request_layered_clear(struct rbd_img_request *img_request) | |
1532 | { | |
1533 | clear_bit(IMG_REQ_LAYERED, &img_request->flags); | |
1534 | smp_mb(); | |
1535 | } | |
1536 | ||
1537 | static bool img_request_layered_test(struct rbd_img_request *img_request) | |
1538 | { | |
1539 | smp_mb(); | |
1540 | return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0; | |
1541 | } | |
1542 | ||
1543 | static void | |
1544 | rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request) | |
1545 | { | |
1546 | u64 xferred = obj_request->xferred; | |
1547 | u64 length = obj_request->length; | |
1548 | ||
1549 | dout("%s: obj %p img %p result %d %llu/%llu\n", __func__, | |
1550 | obj_request, obj_request->img_request, obj_request->result, | |
1551 | xferred, length); | |
1552 | /* | |
1553 | * ENOENT means a hole in the image. We zero-fill the entire | |
1554 | * length of the request. A short read also implies zero-fill | |
1555 | * to the end of the request. An error requires the whole | |
1556 | * length of the request to be reported finished with an error | |
1557 | * to the block layer. In each case we update the xferred | |
1558 | * count to indicate the whole request was satisfied. | |
1559 | */ | |
1560 | rbd_assert(obj_request->type != OBJ_REQUEST_NODATA); | |
1561 | if (obj_request->result == -ENOENT) { | |
1562 | if (obj_request->type == OBJ_REQUEST_BIO) | |
1563 | zero_bio_chain(obj_request->bio_list, 0); | |
1564 | else | |
1565 | zero_pages(obj_request->pages, 0, length); | |
1566 | obj_request->result = 0; | |
1567 | } else if (xferred < length && !obj_request->result) { | |
1568 | if (obj_request->type == OBJ_REQUEST_BIO) | |
1569 | zero_bio_chain(obj_request->bio_list, xferred); | |
1570 | else | |
1571 | zero_pages(obj_request->pages, xferred, length); | |
1572 | } | |
1573 | obj_request->xferred = length; | |
1574 | obj_request_done_set(obj_request); | |
1575 | } | |
1576 | ||
1577 | static void rbd_obj_request_complete(struct rbd_obj_request *obj_request) | |
1578 | { | |
1579 | dout("%s: obj %p cb %p\n", __func__, obj_request, | |
1580 | obj_request->callback); | |
1581 | if (obj_request->callback) | |
1582 | obj_request->callback(obj_request); | |
1583 | else | |
1584 | complete_all(&obj_request->completion); | |
1585 | } | |
1586 | ||
1587 | static void rbd_osd_trivial_callback(struct rbd_obj_request *obj_request) | |
1588 | { | |
1589 | dout("%s: obj %p\n", __func__, obj_request); | |
1590 | obj_request_done_set(obj_request); | |
1591 | } | |
1592 | ||
1593 | static void rbd_osd_read_callback(struct rbd_obj_request *obj_request) | |
1594 | { | |
1595 | struct rbd_img_request *img_request = NULL; | |
1596 | struct rbd_device *rbd_dev = NULL; | |
1597 | bool layered = false; | |
1598 | ||
1599 | if (obj_request_img_data_test(obj_request)) { | |
1600 | img_request = obj_request->img_request; | |
1601 | layered = img_request && img_request_layered_test(img_request); | |
1602 | rbd_dev = img_request->rbd_dev; | |
1603 | } | |
1604 | ||
1605 | dout("%s: obj %p img %p result %d %llu/%llu\n", __func__, | |
1606 | obj_request, img_request, obj_request->result, | |
1607 | obj_request->xferred, obj_request->length); | |
1608 | if (layered && obj_request->result == -ENOENT && | |
1609 | obj_request->img_offset < rbd_dev->parent_overlap) | |
1610 | rbd_img_parent_read(obj_request); | |
1611 | else if (img_request) | |
1612 | rbd_img_obj_request_read_callback(obj_request); | |
1613 | else | |
1614 | obj_request_done_set(obj_request); | |
1615 | } | |
1616 | ||
1617 | static void rbd_osd_write_callback(struct rbd_obj_request *obj_request) | |
1618 | { | |
1619 | dout("%s: obj %p result %d %llu\n", __func__, obj_request, | |
1620 | obj_request->result, obj_request->length); | |
1621 | /* | |
1622 | * There is no such thing as a successful short write. Set | |
1623 | * it to our originally-requested length. | |
1624 | */ | |
1625 | obj_request->xferred = obj_request->length; | |
1626 | obj_request_done_set(obj_request); | |
1627 | } | |
1628 | ||
1629 | /* | |
1630 | * For a simple stat call there's nothing to do. We'll do more if | |
1631 | * this is part of a write sequence for a layered image. | |
1632 | */ | |
1633 | static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request) | |
1634 | { | |
1635 | dout("%s: obj %p\n", __func__, obj_request); | |
1636 | obj_request_done_set(obj_request); | |
1637 | } | |
1638 | ||
1639 | static void rbd_osd_req_callback(struct ceph_osd_request *osd_req, | |
1640 | struct ceph_msg *msg) | |
1641 | { | |
1642 | struct rbd_obj_request *obj_request = osd_req->r_priv; | |
1643 | u16 opcode; | |
1644 | ||
1645 | dout("%s: osd_req %p msg %p\n", __func__, osd_req, msg); | |
1646 | rbd_assert(osd_req == obj_request->osd_req); | |
1647 | if (obj_request_img_data_test(obj_request)) { | |
1648 | rbd_assert(obj_request->img_request); | |
1649 | rbd_assert(obj_request->which != BAD_WHICH); | |
1650 | } else { | |
1651 | rbd_assert(obj_request->which == BAD_WHICH); | |
1652 | } | |
1653 | ||
1654 | if (osd_req->r_result < 0) | |
1655 | obj_request->result = osd_req->r_result; | |
1656 | ||
1657 | rbd_assert(osd_req->r_num_ops <= CEPH_OSD_MAX_OP); | |
1658 | ||
1659 | /* | |
1660 | * We support a 64-bit length, but ultimately it has to be | |
1661 | * passed to blk_end_request(), which takes an unsigned int. | |
1662 | */ | |
1663 | obj_request->xferred = osd_req->r_reply_op_len[0]; | |
1664 | rbd_assert(obj_request->xferred < (u64)UINT_MAX); | |
1665 | ||
1666 | opcode = osd_req->r_ops[0].op; | |
1667 | switch (opcode) { | |
1668 | case CEPH_OSD_OP_READ: | |
1669 | rbd_osd_read_callback(obj_request); | |
1670 | break; | |
1671 | case CEPH_OSD_OP_SETALLOCHINT: | |
1672 | rbd_assert(osd_req->r_ops[1].op == CEPH_OSD_OP_WRITE); | |
1673 | /* fall through */ | |
1674 | case CEPH_OSD_OP_WRITE: | |
1675 | rbd_osd_write_callback(obj_request); | |
1676 | break; | |
1677 | case CEPH_OSD_OP_STAT: | |
1678 | rbd_osd_stat_callback(obj_request); | |
1679 | break; | |
1680 | case CEPH_OSD_OP_CALL: | |
1681 | case CEPH_OSD_OP_NOTIFY_ACK: | |
1682 | case CEPH_OSD_OP_WATCH: | |
1683 | rbd_osd_trivial_callback(obj_request); | |
1684 | break; | |
1685 | default: | |
1686 | rbd_warn(NULL, "%s: unsupported op %hu\n", | |
1687 | obj_request->object_name, (unsigned short) opcode); | |
1688 | break; | |
1689 | } | |
1690 | ||
1691 | if (obj_request_done_test(obj_request)) | |
1692 | rbd_obj_request_complete(obj_request); | |
1693 | } | |
1694 | ||
1695 | static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request) | |
1696 | { | |
1697 | struct rbd_img_request *img_request = obj_request->img_request; | |
1698 | struct ceph_osd_request *osd_req = obj_request->osd_req; | |
1699 | u64 snap_id; | |
1700 | ||
1701 | rbd_assert(osd_req != NULL); | |
1702 | ||
1703 | snap_id = img_request ? img_request->snap_id : CEPH_NOSNAP; | |
1704 | ceph_osdc_build_request(osd_req, obj_request->offset, | |
1705 | NULL, snap_id, NULL); | |
1706 | } | |
1707 | ||
1708 | static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request) | |
1709 | { | |
1710 | struct rbd_img_request *img_request = obj_request->img_request; | |
1711 | struct ceph_osd_request *osd_req = obj_request->osd_req; | |
1712 | struct ceph_snap_context *snapc; | |
1713 | struct timespec mtime = CURRENT_TIME; | |
1714 | ||
1715 | rbd_assert(osd_req != NULL); | |
1716 | ||
1717 | snapc = img_request ? img_request->snapc : NULL; | |
1718 | ceph_osdc_build_request(osd_req, obj_request->offset, | |
1719 | snapc, CEPH_NOSNAP, &mtime); | |
1720 | } | |
1721 | ||
1722 | /* | |
1723 | * Create an osd request. A read request has one osd op (read). | |
1724 | * A write request has either one (watch) or two (hint+write) osd ops. | |
1725 | * (All rbd data writes are prefixed with an allocation hint op, but | |
1726 | * technically osd watch is a write request, hence this distinction.) | |
1727 | */ | |
1728 | static struct ceph_osd_request *rbd_osd_req_create( | |
1729 | struct rbd_device *rbd_dev, | |
1730 | bool write_request, | |
1731 | unsigned int num_ops, | |
1732 | struct rbd_obj_request *obj_request) | |
1733 | { | |
1734 | struct ceph_snap_context *snapc = NULL; | |
1735 | struct ceph_osd_client *osdc; | |
1736 | struct ceph_osd_request *osd_req; | |
1737 | ||
1738 | if (obj_request_img_data_test(obj_request)) { | |
1739 | struct rbd_img_request *img_request = obj_request->img_request; | |
1740 | ||
1741 | rbd_assert(write_request == | |
1742 | img_request_write_test(img_request)); | |
1743 | if (write_request) | |
1744 | snapc = img_request->snapc; | |
1745 | } | |
1746 | ||
1747 | rbd_assert(num_ops == 1 || (write_request && num_ops == 2)); | |
1748 | ||
1749 | /* Allocate and initialize the request, for the num_ops ops */ | |
1750 | ||
1751 | osdc = &rbd_dev->rbd_client->client->osdc; | |
1752 | osd_req = ceph_osdc_alloc_request(osdc, snapc, num_ops, false, | |
1753 | GFP_ATOMIC); | |
1754 | if (!osd_req) | |
1755 | return NULL; /* ENOMEM */ | |
1756 | ||
1757 | if (write_request) | |
1758 | osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK; | |
1759 | else | |
1760 | osd_req->r_flags = CEPH_OSD_FLAG_READ; | |
1761 | ||
1762 | osd_req->r_callback = rbd_osd_req_callback; | |
1763 | osd_req->r_priv = obj_request; | |
1764 | ||
1765 | osd_req->r_base_oloc.pool = ceph_file_layout_pg_pool(rbd_dev->layout); | |
1766 | ceph_oid_set_name(&osd_req->r_base_oid, obj_request->object_name); | |
1767 | ||
1768 | return osd_req; | |
1769 | } | |
1770 | ||
1771 | /* | |
1772 | * Create a copyup osd request based on the information in the | |
1773 | * object request supplied. A copyup request has three osd ops, | |
1774 | * a copyup method call, a hint op, and a write op. | |
1775 | */ | |
1776 | static struct ceph_osd_request * | |
1777 | rbd_osd_req_create_copyup(struct rbd_obj_request *obj_request) | |
1778 | { | |
1779 | struct rbd_img_request *img_request; | |
1780 | struct ceph_snap_context *snapc; | |
1781 | struct rbd_device *rbd_dev; | |
1782 | struct ceph_osd_client *osdc; | |
1783 | struct ceph_osd_request *osd_req; | |
1784 | ||
1785 | rbd_assert(obj_request_img_data_test(obj_request)); | |
1786 | img_request = obj_request->img_request; | |
1787 | rbd_assert(img_request); | |
1788 | rbd_assert(img_request_write_test(img_request)); | |
1789 | ||
1790 | /* Allocate and initialize the request, for the three ops */ | |
1791 | ||
1792 | snapc = img_request->snapc; | |
1793 | rbd_dev = img_request->rbd_dev; | |
1794 | osdc = &rbd_dev->rbd_client->client->osdc; | |
1795 | osd_req = ceph_osdc_alloc_request(osdc, snapc, 3, false, GFP_ATOMIC); | |
1796 | if (!osd_req) | |
1797 | return NULL; /* ENOMEM */ | |
1798 | ||
1799 | osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK; | |
1800 | osd_req->r_callback = rbd_osd_req_callback; | |
1801 | osd_req->r_priv = obj_request; | |
1802 | ||
1803 | osd_req->r_base_oloc.pool = ceph_file_layout_pg_pool(rbd_dev->layout); | |
1804 | ceph_oid_set_name(&osd_req->r_base_oid, obj_request->object_name); | |
1805 | ||
1806 | return osd_req; | |
1807 | } | |
1808 | ||
1809 | ||
1810 | static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req) | |
1811 | { | |
1812 | ceph_osdc_put_request(osd_req); | |
1813 | } | |
1814 | ||
1815 | /* object_name is assumed to be a non-null pointer and NUL-terminated */ | |
1816 | ||
1817 | static struct rbd_obj_request *rbd_obj_request_create(const char *object_name, | |
1818 | u64 offset, u64 length, | |
1819 | enum obj_request_type type) | |
1820 | { | |
1821 | struct rbd_obj_request *obj_request; | |
1822 | size_t size; | |
1823 | char *name; | |
1824 | ||
1825 | rbd_assert(obj_request_type_valid(type)); | |
1826 | ||
1827 | size = strlen(object_name) + 1; | |
1828 | name = kmalloc(size, GFP_KERNEL); | |
1829 | if (!name) | |
1830 | return NULL; | |
1831 | ||
1832 | obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_KERNEL); | |
1833 | if (!obj_request) { | |
1834 | kfree(name); | |
1835 | return NULL; | |
1836 | } | |
1837 | ||
1838 | obj_request->object_name = memcpy(name, object_name, size); | |
1839 | obj_request->offset = offset; | |
1840 | obj_request->length = length; | |
1841 | obj_request->flags = 0; | |
1842 | obj_request->which = BAD_WHICH; | |
1843 | obj_request->type = type; | |
1844 | INIT_LIST_HEAD(&obj_request->links); | |
1845 | init_completion(&obj_request->completion); | |
1846 | kref_init(&obj_request->kref); | |
1847 | ||
1848 | dout("%s: \"%s\" %llu/%llu %d -> obj %p\n", __func__, object_name, | |
1849 | offset, length, (int)type, obj_request); | |
1850 | ||
1851 | return obj_request; | |
1852 | } | |
1853 | ||
1854 | static void rbd_obj_request_destroy(struct kref *kref) | |
1855 | { | |
1856 | struct rbd_obj_request *obj_request; | |
1857 | ||
1858 | obj_request = container_of(kref, struct rbd_obj_request, kref); | |
1859 | ||
1860 | dout("%s: obj %p\n", __func__, obj_request); | |
1861 | ||
1862 | rbd_assert(obj_request->img_request == NULL); | |
1863 | rbd_assert(obj_request->which == BAD_WHICH); | |
1864 | ||
1865 | if (obj_request->osd_req) | |
1866 | rbd_osd_req_destroy(obj_request->osd_req); | |
1867 | ||
1868 | rbd_assert(obj_request_type_valid(obj_request->type)); | |
1869 | switch (obj_request->type) { | |
1870 | case OBJ_REQUEST_NODATA: | |
1871 | break; /* Nothing to do */ | |
1872 | case OBJ_REQUEST_BIO: | |
1873 | if (obj_request->bio_list) | |
1874 | bio_chain_put(obj_request->bio_list); | |
1875 | break; | |
1876 | case OBJ_REQUEST_PAGES: | |
1877 | if (obj_request->pages) | |
1878 | ceph_release_page_vector(obj_request->pages, | |
1879 | obj_request->page_count); | |
1880 | break; | |
1881 | } | |
1882 | ||
1883 | kfree(obj_request->object_name); | |
1884 | obj_request->object_name = NULL; | |
1885 | kmem_cache_free(rbd_obj_request_cache, obj_request); | |
1886 | } | |
1887 | ||
1888 | /* It's OK to call this for a device with no parent */ | |
1889 | ||
1890 | static void rbd_spec_put(struct rbd_spec *spec); | |
1891 | static void rbd_dev_unparent(struct rbd_device *rbd_dev) | |
1892 | { | |
1893 | rbd_dev_remove_parent(rbd_dev); | |
1894 | rbd_spec_put(rbd_dev->parent_spec); | |
1895 | rbd_dev->parent_spec = NULL; | |
1896 | rbd_dev->parent_overlap = 0; | |
1897 | } | |
1898 | ||
1899 | /* | |
1900 | * Parent image reference counting is used to determine when an | |
1901 | * image's parent fields can be safely torn down--after there are no | |
1902 | * more in-flight requests to the parent image. When the last | |
1903 | * reference is dropped, cleaning them up is safe. | |
1904 | */ | |
1905 | static void rbd_dev_parent_put(struct rbd_device *rbd_dev) | |
1906 | { | |
1907 | int counter; | |
1908 | ||
1909 | if (!rbd_dev->parent_spec) | |
1910 | return; | |
1911 | ||
1912 | counter = atomic_dec_return_safe(&rbd_dev->parent_ref); | |
1913 | if (counter > 0) | |
1914 | return; | |
1915 | ||
1916 | /* Last reference; clean up parent data structures */ | |
1917 | ||
1918 | if (!counter) | |
1919 | rbd_dev_unparent(rbd_dev); | |
1920 | else | |
1921 | rbd_warn(rbd_dev, "parent reference underflow\n"); | |
1922 | } | |
1923 | ||
1924 | /* | |
1925 | * If an image has a non-zero parent overlap, get a reference to its | |
1926 | * parent. | |
1927 | * | |
1928 | * We must get the reference before checking for the overlap to | |
1929 | * coordinate properly with zeroing the parent overlap in | |
1930 | * rbd_dev_v2_parent_info() when an image gets flattened. We | |
1931 | * drop it again if there is no overlap. | |
1932 | * | |
1933 | * Returns true if the rbd device has a parent with a non-zero | |
1934 | * overlap and a reference for it was successfully taken, or | |
1935 | * false otherwise. | |
1936 | */ | |
1937 | static bool rbd_dev_parent_get(struct rbd_device *rbd_dev) | |
1938 | { | |
1939 | int counter; | |
1940 | ||
1941 | if (!rbd_dev->parent_spec) | |
1942 | return false; | |
1943 | ||
1944 | counter = atomic_inc_return_safe(&rbd_dev->parent_ref); | |
1945 | if (counter > 0 && rbd_dev->parent_overlap) | |
1946 | return true; | |
1947 | ||
1948 | /* Image was flattened, but parent is not yet torn down */ | |
1949 | ||
1950 | if (counter < 0) | |
1951 | rbd_warn(rbd_dev, "parent reference overflow\n"); | |
1952 | ||
1953 | return false; | |
1954 | } | |
1955 | ||
1956 | /* | |
1957 | * Caller is responsible for filling in the list of object requests | |
1958 | * that comprises the image request, and the Linux request pointer | |
1959 | * (if there is one). | |
1960 | */ | |
1961 | static struct rbd_img_request *rbd_img_request_create( | |
1962 | struct rbd_device *rbd_dev, | |
1963 | u64 offset, u64 length, | |
1964 | bool write_request) | |
1965 | { | |
1966 | struct rbd_img_request *img_request; | |
1967 | ||
1968 | img_request = kmem_cache_alloc(rbd_img_request_cache, GFP_ATOMIC); | |
1969 | if (!img_request) | |
1970 | return NULL; | |
1971 | ||
1972 | if (write_request) { | |
1973 | down_read(&rbd_dev->header_rwsem); | |
1974 | ceph_get_snap_context(rbd_dev->header.snapc); | |
1975 | up_read(&rbd_dev->header_rwsem); | |
1976 | } | |
1977 | ||
1978 | img_request->rq = NULL; | |
1979 | img_request->rbd_dev = rbd_dev; | |
1980 | img_request->offset = offset; | |
1981 | img_request->length = length; | |
1982 | img_request->flags = 0; | |
1983 | if (write_request) { | |
1984 | img_request_write_set(img_request); | |
1985 | img_request->snapc = rbd_dev->header.snapc; | |
1986 | } else { | |
1987 | img_request->snap_id = rbd_dev->spec->snap_id; | |
1988 | } | |
1989 | if (rbd_dev_parent_get(rbd_dev)) | |
1990 | img_request_layered_set(img_request); | |
1991 | spin_lock_init(&img_request->completion_lock); | |
1992 | img_request->next_completion = 0; | |
1993 | img_request->callback = NULL; | |
1994 | img_request->result = 0; | |
1995 | img_request->obj_request_count = 0; | |
1996 | INIT_LIST_HEAD(&img_request->obj_requests); | |
1997 | kref_init(&img_request->kref); | |
1998 | ||
1999 | dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev, | |
2000 | write_request ? "write" : "read", offset, length, | |
2001 | img_request); | |
2002 | ||
2003 | return img_request; | |
2004 | } | |
2005 | ||
2006 | static void rbd_img_request_destroy(struct kref *kref) | |
2007 | { | |
2008 | struct rbd_img_request *img_request; | |
2009 | struct rbd_obj_request *obj_request; | |
2010 | struct rbd_obj_request *next_obj_request; | |
2011 | ||
2012 | img_request = container_of(kref, struct rbd_img_request, kref); | |
2013 | ||
2014 | dout("%s: img %p\n", __func__, img_request); | |
2015 | ||
2016 | for_each_obj_request_safe(img_request, obj_request, next_obj_request) | |
2017 | rbd_img_obj_request_del(img_request, obj_request); | |
2018 | rbd_assert(img_request->obj_request_count == 0); | |
2019 | ||
2020 | if (img_request_layered_test(img_request)) { | |
2021 | img_request_layered_clear(img_request); | |
2022 | rbd_dev_parent_put(img_request->rbd_dev); | |
2023 | } | |
2024 | ||
2025 | if (img_request_write_test(img_request)) | |
2026 | ceph_put_snap_context(img_request->snapc); | |
2027 | ||
2028 | kmem_cache_free(rbd_img_request_cache, img_request); | |
2029 | } | |
2030 | ||
2031 | static struct rbd_img_request *rbd_parent_request_create( | |
2032 | struct rbd_obj_request *obj_request, | |
2033 | u64 img_offset, u64 length) | |
2034 | { | |
2035 | struct rbd_img_request *parent_request; | |
2036 | struct rbd_device *rbd_dev; | |
2037 | ||
2038 | rbd_assert(obj_request->img_request); | |
2039 | rbd_dev = obj_request->img_request->rbd_dev; | |
2040 | ||
2041 | parent_request = rbd_img_request_create(rbd_dev->parent, | |
2042 | img_offset, length, false); | |
2043 | if (!parent_request) | |
2044 | return NULL; | |
2045 | ||
2046 | img_request_child_set(parent_request); | |
2047 | rbd_obj_request_get(obj_request); | |
2048 | parent_request->obj_request = obj_request; | |
2049 | ||
2050 | return parent_request; | |
2051 | } | |
2052 | ||
2053 | static void rbd_parent_request_destroy(struct kref *kref) | |
2054 | { | |
2055 | struct rbd_img_request *parent_request; | |
2056 | struct rbd_obj_request *orig_request; | |
2057 | ||
2058 | parent_request = container_of(kref, struct rbd_img_request, kref); | |
2059 | orig_request = parent_request->obj_request; | |
2060 | ||
2061 | parent_request->obj_request = NULL; | |
2062 | rbd_obj_request_put(orig_request); | |
2063 | img_request_child_clear(parent_request); | |
2064 | ||
2065 | rbd_img_request_destroy(kref); | |
2066 | } | |
2067 | ||
2068 | static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request) | |
2069 | { | |
2070 | struct rbd_img_request *img_request; | |
2071 | unsigned int xferred; | |
2072 | int result; | |
2073 | bool more; | |
2074 | ||
2075 | rbd_assert(obj_request_img_data_test(obj_request)); | |
2076 | img_request = obj_request->img_request; | |
2077 | ||
2078 | rbd_assert(obj_request->xferred <= (u64)UINT_MAX); | |
2079 | xferred = (unsigned int)obj_request->xferred; | |
2080 | result = obj_request->result; | |
2081 | if (result) { | |
2082 | struct rbd_device *rbd_dev = img_request->rbd_dev; | |
2083 | ||
2084 | rbd_warn(rbd_dev, "%s %llx at %llx (%llx)\n", | |
2085 | img_request_write_test(img_request) ? "write" : "read", | |
2086 | obj_request->length, obj_request->img_offset, | |
2087 | obj_request->offset); | |
2088 | rbd_warn(rbd_dev, " result %d xferred %x\n", | |
2089 | result, xferred); | |
2090 | if (!img_request->result) | |
2091 | img_request->result = result; | |
2092 | } | |
2093 | ||
2094 | /* Image object requests don't own their page array */ | |
2095 | ||
2096 | if (obj_request->type == OBJ_REQUEST_PAGES) { | |
2097 | obj_request->pages = NULL; | |
2098 | obj_request->page_count = 0; | |
2099 | } | |
2100 | ||
2101 | if (img_request_child_test(img_request)) { | |
2102 | rbd_assert(img_request->obj_request != NULL); | |
2103 | more = obj_request->which < img_request->obj_request_count - 1; | |
2104 | } else { | |
2105 | rbd_assert(img_request->rq != NULL); | |
2106 | more = blk_end_request(img_request->rq, result, xferred); | |
2107 | } | |
2108 | ||
2109 | return more; | |
2110 | } | |
2111 | ||
2112 | static void rbd_img_obj_callback(struct rbd_obj_request *obj_request) | |
2113 | { | |
2114 | struct rbd_img_request *img_request; | |
2115 | u32 which = obj_request->which; | |
2116 | bool more = true; | |
2117 | ||
2118 | rbd_assert(obj_request_img_data_test(obj_request)); | |
2119 | img_request = obj_request->img_request; | |
2120 | ||
2121 | dout("%s: img %p obj %p\n", __func__, img_request, obj_request); | |
2122 | rbd_assert(img_request != NULL); | |
2123 | rbd_assert(img_request->obj_request_count > 0); | |
2124 | rbd_assert(which != BAD_WHICH); | |
2125 | rbd_assert(which < img_request->obj_request_count); | |
2126 | ||
2127 | spin_lock_irq(&img_request->completion_lock); | |
2128 | if (which != img_request->next_completion) | |
2129 | goto out; | |
2130 | ||
2131 | for_each_obj_request_from(img_request, obj_request) { | |
2132 | rbd_assert(more); | |
2133 | rbd_assert(which < img_request->obj_request_count); | |
2134 | ||
2135 | if (!obj_request_done_test(obj_request)) | |
2136 | break; | |
2137 | more = rbd_img_obj_end_request(obj_request); | |
2138 | which++; | |
2139 | } | |
2140 | ||
2141 | rbd_assert(more ^ (which == img_request->obj_request_count)); | |
2142 | img_request->next_completion = which; | |
2143 | out: | |
2144 | spin_unlock_irq(&img_request->completion_lock); | |
2145 | ||
2146 | if (!more) | |
2147 | rbd_img_request_complete(img_request); | |
2148 | } | |
2149 | ||
2150 | /* | |
2151 | * Split up an image request into one or more object requests, each | |
2152 | * to a different object. The "type" parameter indicates whether | |
2153 | * "data_desc" is the pointer to the head of a list of bio | |
2154 | * structures, or the base of a page array. In either case this | |
2155 | * function assumes data_desc describes memory sufficient to hold | |
2156 | * all data described by the image request. | |
2157 | */ | |
2158 | static int rbd_img_request_fill(struct rbd_img_request *img_request, | |
2159 | enum obj_request_type type, | |
2160 | void *data_desc) | |
2161 | { | |
2162 | struct rbd_device *rbd_dev = img_request->rbd_dev; | |
2163 | struct rbd_obj_request *obj_request = NULL; | |
2164 | struct rbd_obj_request *next_obj_request; | |
2165 | bool write_request = img_request_write_test(img_request); | |
2166 | struct bio *bio_list = NULL; | |
2167 | unsigned int bio_offset = 0; | |
2168 | struct page **pages = NULL; | |
2169 | u64 img_offset; | |
2170 | u64 resid; | |
2171 | u16 opcode; | |
2172 | ||
2173 | dout("%s: img %p type %d data_desc %p\n", __func__, img_request, | |
2174 | (int)type, data_desc); | |
2175 | ||
2176 | opcode = write_request ? CEPH_OSD_OP_WRITE : CEPH_OSD_OP_READ; | |
2177 | img_offset = img_request->offset; | |
2178 | resid = img_request->length; | |
2179 | rbd_assert(resid > 0); | |
2180 | ||
2181 | if (type == OBJ_REQUEST_BIO) { | |
2182 | bio_list = data_desc; | |
2183 | rbd_assert(img_offset == | |
2184 | bio_list->bi_iter.bi_sector << SECTOR_SHIFT); | |
2185 | } else { | |
2186 | rbd_assert(type == OBJ_REQUEST_PAGES); | |
2187 | pages = data_desc; | |
2188 | } | |
2189 | ||
2190 | while (resid) { | |
2191 | struct ceph_osd_request *osd_req; | |
2192 | const char *object_name; | |
2193 | u64 offset; | |
2194 | u64 length; | |
2195 | unsigned int which = 0; | |
2196 | ||
2197 | object_name = rbd_segment_name(rbd_dev, img_offset); | |
2198 | if (!object_name) | |
2199 | goto out_unwind; | |
2200 | offset = rbd_segment_offset(rbd_dev, img_offset); | |
2201 | length = rbd_segment_length(rbd_dev, img_offset, resid); | |
2202 | obj_request = rbd_obj_request_create(object_name, | |
2203 | offset, length, type); | |
2204 | /* object request has its own copy of the object name */ | |
2205 | rbd_segment_name_free(object_name); | |
2206 | if (!obj_request) | |
2207 | goto out_unwind; | |
2208 | ||
2209 | /* | |
2210 | * set obj_request->img_request before creating the | |
2211 | * osd_request so that it gets the right snapc | |
2212 | */ | |
2213 | rbd_img_obj_request_add(img_request, obj_request); | |
2214 | ||
2215 | if (type == OBJ_REQUEST_BIO) { | |
2216 | unsigned int clone_size; | |
2217 | ||
2218 | rbd_assert(length <= (u64)UINT_MAX); | |
2219 | clone_size = (unsigned int)length; | |
2220 | obj_request->bio_list = | |
2221 | bio_chain_clone_range(&bio_list, | |
2222 | &bio_offset, | |
2223 | clone_size, | |
2224 | GFP_ATOMIC); | |
2225 | if (!obj_request->bio_list) | |
2226 | goto out_unwind; | |
2227 | } else { | |
2228 | unsigned int page_count; | |
2229 | ||
2230 | obj_request->pages = pages; | |
2231 | page_count = (u32)calc_pages_for(offset, length); | |
2232 | obj_request->page_count = page_count; | |
2233 | if ((offset + length) & ~PAGE_MASK) | |
2234 | page_count--; /* more on last page */ | |
2235 | pages += page_count; | |
2236 | } | |
2237 | ||
2238 | osd_req = rbd_osd_req_create(rbd_dev, write_request, | |
2239 | (write_request ? 2 : 1), | |
2240 | obj_request); | |
2241 | if (!osd_req) | |
2242 | goto out_unwind; | |
2243 | obj_request->osd_req = osd_req; | |
2244 | obj_request->callback = rbd_img_obj_callback; | |
2245 | ||
2246 | if (write_request) { | |
2247 | osd_req_op_alloc_hint_init(osd_req, which, | |
2248 | rbd_obj_bytes(&rbd_dev->header), | |
2249 | rbd_obj_bytes(&rbd_dev->header)); | |
2250 | which++; | |
2251 | } | |
2252 | ||
2253 | osd_req_op_extent_init(osd_req, which, opcode, offset, length, | |
2254 | 0, 0); | |
2255 | if (type == OBJ_REQUEST_BIO) | |
2256 | osd_req_op_extent_osd_data_bio(osd_req, which, | |
2257 | obj_request->bio_list, length); | |
2258 | else | |
2259 | osd_req_op_extent_osd_data_pages(osd_req, which, | |
2260 | obj_request->pages, length, | |
2261 | offset & ~PAGE_MASK, false, false); | |
2262 | ||
2263 | if (write_request) | |
2264 | rbd_osd_req_format_write(obj_request); | |
2265 | else | |
2266 | rbd_osd_req_format_read(obj_request); | |
2267 | ||
2268 | obj_request->img_offset = img_offset; | |
2269 | ||
2270 | img_offset += length; | |
2271 | resid -= length; | |
2272 | } | |
2273 | ||
2274 | return 0; | |
2275 | ||
2276 | out_unwind: | |
2277 | for_each_obj_request_safe(img_request, obj_request, next_obj_request) | |
2278 | rbd_img_obj_request_del(img_request, obj_request); | |
2279 | ||
2280 | return -ENOMEM; | |
2281 | } | |
2282 | ||
2283 | static void | |
2284 | rbd_img_obj_copyup_callback(struct rbd_obj_request *obj_request) | |
2285 | { | |
2286 | struct rbd_img_request *img_request; | |
2287 | struct rbd_device *rbd_dev; | |
2288 | struct page **pages; | |
2289 | u32 page_count; | |
2290 | ||
2291 | rbd_assert(obj_request->type == OBJ_REQUEST_BIO); | |
2292 | rbd_assert(obj_request_img_data_test(obj_request)); | |
2293 | img_request = obj_request->img_request; | |
2294 | rbd_assert(img_request); | |
2295 | ||
2296 | rbd_dev = img_request->rbd_dev; | |
2297 | rbd_assert(rbd_dev); | |
2298 | ||
2299 | pages = obj_request->copyup_pages; | |
2300 | rbd_assert(pages != NULL); | |
2301 | obj_request->copyup_pages = NULL; | |
2302 | page_count = obj_request->copyup_page_count; | |
2303 | rbd_assert(page_count); | |
2304 | obj_request->copyup_page_count = 0; | |
2305 | ceph_release_page_vector(pages, page_count); | |
2306 | ||
2307 | /* | |
2308 | * We want the transfer count to reflect the size of the | |
2309 | * original write request. There is no such thing as a | |
2310 | * successful short write, so if the request was successful | |
2311 | * we can just set it to the originally-requested length. | |
2312 | */ | |
2313 | if (!obj_request->result) | |
2314 | obj_request->xferred = obj_request->length; | |
2315 | ||
2316 | /* Finish up with the normal image object callback */ | |
2317 | ||
2318 | rbd_img_obj_callback(obj_request); | |
2319 | } | |
2320 | ||
2321 | static void | |
2322 | rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request) | |
2323 | { | |
2324 | struct rbd_obj_request *orig_request; | |
2325 | struct ceph_osd_request *osd_req; | |
2326 | struct ceph_osd_client *osdc; | |
2327 | struct rbd_device *rbd_dev; | |
2328 | struct page **pages; | |
2329 | u32 page_count; | |
2330 | int img_result; | |
2331 | u64 parent_length; | |
2332 | u64 offset; | |
2333 | u64 length; | |
2334 | ||
2335 | rbd_assert(img_request_child_test(img_request)); | |
2336 | ||
2337 | /* First get what we need from the image request */ | |
2338 | ||
2339 | pages = img_request->copyup_pages; | |
2340 | rbd_assert(pages != NULL); | |
2341 | img_request->copyup_pages = NULL; | |
2342 | page_count = img_request->copyup_page_count; | |
2343 | rbd_assert(page_count); | |
2344 | img_request->copyup_page_count = 0; | |
2345 | ||
2346 | orig_request = img_request->obj_request; | |
2347 | rbd_assert(orig_request != NULL); | |
2348 | rbd_assert(obj_request_type_valid(orig_request->type)); | |
2349 | img_result = img_request->result; | |
2350 | parent_length = img_request->length; | |
2351 | rbd_assert(parent_length == img_request->xferred); | |
2352 | rbd_img_request_put(img_request); | |
2353 | ||
2354 | rbd_assert(orig_request->img_request); | |
2355 | rbd_dev = orig_request->img_request->rbd_dev; | |
2356 | rbd_assert(rbd_dev); | |
2357 | ||
2358 | /* | |
2359 | * If the overlap has become 0 (most likely because the | |
2360 | * image has been flattened) we need to free the pages | |
2361 | * and re-submit the original write request. | |
2362 | */ | |
2363 | if (!rbd_dev->parent_overlap) { | |
2364 | struct ceph_osd_client *osdc; | |
2365 | ||
2366 | ceph_release_page_vector(pages, page_count); | |
2367 | osdc = &rbd_dev->rbd_client->client->osdc; | |
2368 | img_result = rbd_obj_request_submit(osdc, orig_request); | |
2369 | if (!img_result) | |
2370 | return; | |
2371 | } | |
2372 | ||
2373 | if (img_result) | |
2374 | goto out_err; | |
2375 | ||
2376 | /* | |
2377 | * The original osd request is of no use to use any more. | |
2378 | * We need a new one that can hold the three ops in a copyup | |
2379 | * request. Allocate the new copyup osd request for the | |
2380 | * original request, and release the old one. | |
2381 | */ | |
2382 | img_result = -ENOMEM; | |
2383 | osd_req = rbd_osd_req_create_copyup(orig_request); | |
2384 | if (!osd_req) | |
2385 | goto out_err; | |
2386 | rbd_osd_req_destroy(orig_request->osd_req); | |
2387 | orig_request->osd_req = osd_req; | |
2388 | orig_request->copyup_pages = pages; | |
2389 | orig_request->copyup_page_count = page_count; | |
2390 | ||
2391 | /* Initialize the copyup op */ | |
2392 | ||
2393 | osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup"); | |
2394 | osd_req_op_cls_request_data_pages(osd_req, 0, pages, parent_length, 0, | |
2395 | false, false); | |
2396 | ||
2397 | /* Then the hint op */ | |
2398 | ||
2399 | osd_req_op_alloc_hint_init(osd_req, 1, rbd_obj_bytes(&rbd_dev->header), | |
2400 | rbd_obj_bytes(&rbd_dev->header)); | |
2401 | ||
2402 | /* And the original write request op */ | |
2403 | ||
2404 | offset = orig_request->offset; | |
2405 | length = orig_request->length; | |
2406 | osd_req_op_extent_init(osd_req, 2, CEPH_OSD_OP_WRITE, | |
2407 | offset, length, 0, 0); | |
2408 | if (orig_request->type == OBJ_REQUEST_BIO) | |
2409 | osd_req_op_extent_osd_data_bio(osd_req, 2, | |
2410 | orig_request->bio_list, length); | |
2411 | else | |
2412 | osd_req_op_extent_osd_data_pages(osd_req, 2, | |
2413 | orig_request->pages, length, | |
2414 | offset & ~PAGE_MASK, false, false); | |
2415 | ||
2416 | rbd_osd_req_format_write(orig_request); | |
2417 | ||
2418 | /* All set, send it off. */ | |
2419 | ||
2420 | orig_request->callback = rbd_img_obj_copyup_callback; | |
2421 | osdc = &rbd_dev->rbd_client->client->osdc; | |
2422 | img_result = rbd_obj_request_submit(osdc, orig_request); | |
2423 | if (!img_result) | |
2424 | return; | |
2425 | out_err: | |
2426 | /* Record the error code and complete the request */ | |
2427 | ||
2428 | orig_request->result = img_result; | |
2429 | orig_request->xferred = 0; | |
2430 | obj_request_done_set(orig_request); | |
2431 | rbd_obj_request_complete(orig_request); | |
2432 | } | |
2433 | ||
2434 | /* | |
2435 | * Read from the parent image the range of data that covers the | |
2436 | * entire target of the given object request. This is used for | |
2437 | * satisfying a layered image write request when the target of an | |
2438 | * object request from the image request does not exist. | |
2439 | * | |
2440 | * A page array big enough to hold the returned data is allocated | |
2441 | * and supplied to rbd_img_request_fill() as the "data descriptor." | |
2442 | * When the read completes, this page array will be transferred to | |
2443 | * the original object request for the copyup operation. | |
2444 | * | |
2445 | * If an error occurs, record it as the result of the original | |
2446 | * object request and mark it done so it gets completed. | |
2447 | */ | |
2448 | static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request) | |
2449 | { | |
2450 | struct rbd_img_request *img_request = NULL; | |
2451 | struct rbd_img_request *parent_request = NULL; | |
2452 | struct rbd_device *rbd_dev; | |
2453 | u64 img_offset; | |
2454 | u64 length; | |
2455 | struct page **pages = NULL; | |
2456 | u32 page_count; | |
2457 | int result; | |
2458 | ||
2459 | rbd_assert(obj_request_img_data_test(obj_request)); | |
2460 | rbd_assert(obj_request_type_valid(obj_request->type)); | |
2461 | ||
2462 | img_request = obj_request->img_request; | |
2463 | rbd_assert(img_request != NULL); | |
2464 | rbd_dev = img_request->rbd_dev; | |
2465 | rbd_assert(rbd_dev->parent != NULL); | |
2466 | ||
2467 | /* | |
2468 | * Determine the byte range covered by the object in the | |
2469 | * child image to which the original request was to be sent. | |
2470 | */ | |
2471 | img_offset = obj_request->img_offset - obj_request->offset; | |
2472 | length = (u64)1 << rbd_dev->header.obj_order; | |
2473 | ||
2474 | /* | |
2475 | * There is no defined parent data beyond the parent | |
2476 | * overlap, so limit what we read at that boundary if | |
2477 | * necessary. | |
2478 | */ | |
2479 | if (img_offset + length > rbd_dev->parent_overlap) { | |
2480 | rbd_assert(img_offset < rbd_dev->parent_overlap); | |
2481 | length = rbd_dev->parent_overlap - img_offset; | |
2482 | } | |
2483 | ||
2484 | /* | |
2485 | * Allocate a page array big enough to receive the data read | |
2486 | * from the parent. | |
2487 | */ | |
2488 | page_count = (u32)calc_pages_for(0, length); | |
2489 | pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); | |
2490 | if (IS_ERR(pages)) { | |
2491 | result = PTR_ERR(pages); | |
2492 | pages = NULL; | |
2493 | goto out_err; | |
2494 | } | |
2495 | ||
2496 | result = -ENOMEM; | |
2497 | parent_request = rbd_parent_request_create(obj_request, | |
2498 | img_offset, length); | |
2499 | if (!parent_request) | |
2500 | goto out_err; | |
2501 | ||
2502 | result = rbd_img_request_fill(parent_request, OBJ_REQUEST_PAGES, pages); | |
2503 | if (result) | |
2504 | goto out_err; | |
2505 | parent_request->copyup_pages = pages; | |
2506 | parent_request->copyup_page_count = page_count; | |
2507 | ||
2508 | parent_request->callback = rbd_img_obj_parent_read_full_callback; | |
2509 | result = rbd_img_request_submit(parent_request); | |
2510 | if (!result) | |
2511 | return 0; | |
2512 | ||
2513 | parent_request->copyup_pages = NULL; | |
2514 | parent_request->copyup_page_count = 0; | |
2515 | parent_request->obj_request = NULL; | |
2516 | rbd_obj_request_put(obj_request); | |
2517 | out_err: | |
2518 | if (pages) | |
2519 | ceph_release_page_vector(pages, page_count); | |
2520 | if (parent_request) | |
2521 | rbd_img_request_put(parent_request); | |
2522 | obj_request->result = result; | |
2523 | obj_request->xferred = 0; | |
2524 | obj_request_done_set(obj_request); | |
2525 | ||
2526 | return result; | |
2527 | } | |
2528 | ||
2529 | static void rbd_img_obj_exists_callback(struct rbd_obj_request *obj_request) | |
2530 | { | |
2531 | struct rbd_obj_request *orig_request; | |
2532 | struct rbd_device *rbd_dev; | |
2533 | int result; | |
2534 | ||
2535 | rbd_assert(!obj_request_img_data_test(obj_request)); | |
2536 | ||
2537 | /* | |
2538 | * All we need from the object request is the original | |
2539 | * request and the result of the STAT op. Grab those, then | |
2540 | * we're done with the request. | |
2541 | */ | |
2542 | orig_request = obj_request->obj_request; | |
2543 | obj_request->obj_request = NULL; | |
2544 | rbd_obj_request_put(orig_request); | |
2545 | rbd_assert(orig_request); | |
2546 | rbd_assert(orig_request->img_request); | |
2547 | ||
2548 | result = obj_request->result; | |
2549 | obj_request->result = 0; | |
2550 | ||
2551 | dout("%s: obj %p for obj %p result %d %llu/%llu\n", __func__, | |
2552 | obj_request, orig_request, result, | |
2553 | obj_request->xferred, obj_request->length); | |
2554 | rbd_obj_request_put(obj_request); | |
2555 | ||
2556 | /* | |
2557 | * If the overlap has become 0 (most likely because the | |
2558 | * image has been flattened) we need to free the pages | |
2559 | * and re-submit the original write request. | |
2560 | */ | |
2561 | rbd_dev = orig_request->img_request->rbd_dev; | |
2562 | if (!rbd_dev->parent_overlap) { | |
2563 | struct ceph_osd_client *osdc; | |
2564 | ||
2565 | osdc = &rbd_dev->rbd_client->client->osdc; | |
2566 | result = rbd_obj_request_submit(osdc, orig_request); | |
2567 | if (!result) | |
2568 | return; | |
2569 | } | |
2570 | ||
2571 | /* | |
2572 | * Our only purpose here is to determine whether the object | |
2573 | * exists, and we don't want to treat the non-existence as | |
2574 | * an error. If something else comes back, transfer the | |
2575 | * error to the original request and complete it now. | |
2576 | */ | |
2577 | if (!result) { | |
2578 | obj_request_existence_set(orig_request, true); | |
2579 | } else if (result == -ENOENT) { | |
2580 | obj_request_existence_set(orig_request, false); | |
2581 | } else if (result) { | |
2582 | orig_request->result = result; | |
2583 | goto out; | |
2584 | } | |
2585 | ||
2586 | /* | |
2587 | * Resubmit the original request now that we have recorded | |
2588 | * whether the target object exists. | |
2589 | */ | |
2590 | orig_request->result = rbd_img_obj_request_submit(orig_request); | |
2591 | out: | |
2592 | if (orig_request->result) | |
2593 | rbd_obj_request_complete(orig_request); | |
2594 | } | |
2595 | ||
2596 | static int rbd_img_obj_exists_submit(struct rbd_obj_request *obj_request) | |
2597 | { | |
2598 | struct rbd_obj_request *stat_request; | |
2599 | struct rbd_device *rbd_dev; | |
2600 | struct ceph_osd_client *osdc; | |
2601 | struct page **pages = NULL; | |
2602 | u32 page_count; | |
2603 | size_t size; | |
2604 | int ret; | |
2605 | ||
2606 | /* | |
2607 | * The response data for a STAT call consists of: | |
2608 | * le64 length; | |
2609 | * struct { | |
2610 | * le32 tv_sec; | |
2611 | * le32 tv_nsec; | |
2612 | * } mtime; | |
2613 | */ | |
2614 | size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32); | |
2615 | page_count = (u32)calc_pages_for(0, size); | |
2616 | pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); | |
2617 | if (IS_ERR(pages)) | |
2618 | return PTR_ERR(pages); | |
2619 | ||
2620 | ret = -ENOMEM; | |
2621 | stat_request = rbd_obj_request_create(obj_request->object_name, 0, 0, | |
2622 | OBJ_REQUEST_PAGES); | |
2623 | if (!stat_request) | |
2624 | goto out; | |
2625 | ||
2626 | rbd_obj_request_get(obj_request); | |
2627 | stat_request->obj_request = obj_request; | |
2628 | stat_request->pages = pages; | |
2629 | stat_request->page_count = page_count; | |
2630 | ||
2631 | rbd_assert(obj_request->img_request); | |
2632 | rbd_dev = obj_request->img_request->rbd_dev; | |
2633 | stat_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1, | |
2634 | stat_request); | |
2635 | if (!stat_request->osd_req) | |
2636 | goto out; | |
2637 | stat_request->callback = rbd_img_obj_exists_callback; | |
2638 | ||
2639 | osd_req_op_init(stat_request->osd_req, 0, CEPH_OSD_OP_STAT); | |
2640 | osd_req_op_raw_data_in_pages(stat_request->osd_req, 0, pages, size, 0, | |
2641 | false, false); | |
2642 | rbd_osd_req_format_read(stat_request); | |
2643 | ||
2644 | osdc = &rbd_dev->rbd_client->client->osdc; | |
2645 | ret = rbd_obj_request_submit(osdc, stat_request); | |
2646 | out: | |
2647 | if (ret) | |
2648 | rbd_obj_request_put(obj_request); | |
2649 | ||
2650 | return ret; | |
2651 | } | |
2652 | ||
2653 | static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request) | |
2654 | { | |
2655 | struct rbd_img_request *img_request; | |
2656 | struct rbd_device *rbd_dev; | |
2657 | bool known; | |
2658 | ||
2659 | rbd_assert(obj_request_img_data_test(obj_request)); | |
2660 | ||
2661 | img_request = obj_request->img_request; | |
2662 | rbd_assert(img_request); | |
2663 | rbd_dev = img_request->rbd_dev; | |
2664 | ||
2665 | /* | |
2666 | * Only writes to layered images need special handling. | |
2667 | * Reads and non-layered writes are simple object requests. | |
2668 | * Layered writes that start beyond the end of the overlap | |
2669 | * with the parent have no parent data, so they too are | |
2670 | * simple object requests. Finally, if the target object is | |
2671 | * known to already exist, its parent data has already been | |
2672 | * copied, so a write to the object can also be handled as a | |
2673 | * simple object request. | |
2674 | */ | |
2675 | if (!img_request_write_test(img_request) || | |
2676 | !img_request_layered_test(img_request) || | |
2677 | rbd_dev->parent_overlap <= obj_request->img_offset || | |
2678 | ((known = obj_request_known_test(obj_request)) && | |
2679 | obj_request_exists_test(obj_request))) { | |
2680 | ||
2681 | struct rbd_device *rbd_dev; | |
2682 | struct ceph_osd_client *osdc; | |
2683 | ||
2684 | rbd_dev = obj_request->img_request->rbd_dev; | |
2685 | osdc = &rbd_dev->rbd_client->client->osdc; | |
2686 | ||
2687 | return rbd_obj_request_submit(osdc, obj_request); | |
2688 | } | |
2689 | ||
2690 | /* | |
2691 | * It's a layered write. The target object might exist but | |
2692 | * we may not know that yet. If we know it doesn't exist, | |
2693 | * start by reading the data for the full target object from | |
2694 | * the parent so we can use it for a copyup to the target. | |
2695 | */ | |
2696 | if (known) | |
2697 | return rbd_img_obj_parent_read_full(obj_request); | |
2698 | ||
2699 | /* We don't know whether the target exists. Go find out. */ | |
2700 | ||
2701 | return rbd_img_obj_exists_submit(obj_request); | |
2702 | } | |
2703 | ||
2704 | static int rbd_img_request_submit(struct rbd_img_request *img_request) | |
2705 | { | |
2706 | struct rbd_obj_request *obj_request; | |
2707 | struct rbd_obj_request *next_obj_request; | |
2708 | ||
2709 | dout("%s: img %p\n", __func__, img_request); | |
2710 | for_each_obj_request_safe(img_request, obj_request, next_obj_request) { | |
2711 | int ret; | |
2712 | ||
2713 | ret = rbd_img_obj_request_submit(obj_request); | |
2714 | if (ret) | |
2715 | return ret; | |
2716 | } | |
2717 | ||
2718 | return 0; | |
2719 | } | |
2720 | ||
2721 | static void rbd_img_parent_read_callback(struct rbd_img_request *img_request) | |
2722 | { | |
2723 | struct rbd_obj_request *obj_request; | |
2724 | struct rbd_device *rbd_dev; | |
2725 | u64 obj_end; | |
2726 | u64 img_xferred; | |
2727 | int img_result; | |
2728 | ||
2729 | rbd_assert(img_request_child_test(img_request)); | |
2730 | ||
2731 | /* First get what we need from the image request and release it */ | |
2732 | ||
2733 | obj_request = img_request->obj_request; | |
2734 | img_xferred = img_request->xferred; | |
2735 | img_result = img_request->result; | |
2736 | rbd_img_request_put(img_request); | |
2737 | ||
2738 | /* | |
2739 | * If the overlap has become 0 (most likely because the | |
2740 | * image has been flattened) we need to re-submit the | |
2741 | * original request. | |
2742 | */ | |
2743 | rbd_assert(obj_request); | |
2744 | rbd_assert(obj_request->img_request); | |
2745 | rbd_dev = obj_request->img_request->rbd_dev; | |
2746 | if (!rbd_dev->parent_overlap) { | |
2747 | struct ceph_osd_client *osdc; | |
2748 | ||
2749 | osdc = &rbd_dev->rbd_client->client->osdc; | |
2750 | img_result = rbd_obj_request_submit(osdc, obj_request); | |
2751 | if (!img_result) | |
2752 | return; | |
2753 | } | |
2754 | ||
2755 | obj_request->result = img_result; | |
2756 | if (obj_request->result) | |
2757 | goto out; | |
2758 | ||
2759 | /* | |
2760 | * We need to zero anything beyond the parent overlap | |
2761 | * boundary. Since rbd_img_obj_request_read_callback() | |
2762 | * will zero anything beyond the end of a short read, an | |
2763 | * easy way to do this is to pretend the data from the | |
2764 | * parent came up short--ending at the overlap boundary. | |
2765 | */ | |
2766 | rbd_assert(obj_request->img_offset < U64_MAX - obj_request->length); | |
2767 | obj_end = obj_request->img_offset + obj_request->length; | |
2768 | if (obj_end > rbd_dev->parent_overlap) { | |
2769 | u64 xferred = 0; | |
2770 | ||
2771 | if (obj_request->img_offset < rbd_dev->parent_overlap) | |
2772 | xferred = rbd_dev->parent_overlap - | |
2773 | obj_request->img_offset; | |
2774 | ||
2775 | obj_request->xferred = min(img_xferred, xferred); | |
2776 | } else { | |
2777 | obj_request->xferred = img_xferred; | |
2778 | } | |
2779 | out: | |
2780 | rbd_img_obj_request_read_callback(obj_request); | |
2781 | rbd_obj_request_complete(obj_request); | |
2782 | } | |
2783 | ||
2784 | static void rbd_img_parent_read(struct rbd_obj_request *obj_request) | |
2785 | { | |
2786 | struct rbd_img_request *img_request; | |
2787 | int result; | |
2788 | ||
2789 | rbd_assert(obj_request_img_data_test(obj_request)); | |
2790 | rbd_assert(obj_request->img_request != NULL); | |
2791 | rbd_assert(obj_request->result == (s32) -ENOENT); | |
2792 | rbd_assert(obj_request_type_valid(obj_request->type)); | |
2793 | ||
2794 | /* rbd_read_finish(obj_request, obj_request->length); */ | |
2795 | img_request = rbd_parent_request_create(obj_request, | |
2796 | obj_request->img_offset, | |
2797 | obj_request->length); | |
2798 | result = -ENOMEM; | |
2799 | if (!img_request) | |
2800 | goto out_err; | |
2801 | ||
2802 | if (obj_request->type == OBJ_REQUEST_BIO) | |
2803 | result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO, | |
2804 | obj_request->bio_list); | |
2805 | else | |
2806 | result = rbd_img_request_fill(img_request, OBJ_REQUEST_PAGES, | |
2807 | obj_request->pages); | |
2808 | if (result) | |
2809 | goto out_err; | |
2810 | ||
2811 | img_request->callback = rbd_img_parent_read_callback; | |
2812 | result = rbd_img_request_submit(img_request); | |
2813 | if (result) | |
2814 | goto out_err; | |
2815 | ||
2816 | return; | |
2817 | out_err: | |
2818 | if (img_request) | |
2819 | rbd_img_request_put(img_request); | |
2820 | obj_request->result = result; | |
2821 | obj_request->xferred = 0; | |
2822 | obj_request_done_set(obj_request); | |
2823 | } | |
2824 | ||
2825 | static int rbd_obj_notify_ack_sync(struct rbd_device *rbd_dev, u64 notify_id) | |
2826 | { | |
2827 | struct rbd_obj_request *obj_request; | |
2828 | struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; | |
2829 | int ret; | |
2830 | ||
2831 | obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0, | |
2832 | OBJ_REQUEST_NODATA); | |
2833 | if (!obj_request) | |
2834 | return -ENOMEM; | |
2835 | ||
2836 | ret = -ENOMEM; | |
2837 | obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1, | |
2838 | obj_request); | |
2839 | if (!obj_request->osd_req) | |
2840 | goto out; | |
2841 | ||
2842 | osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_NOTIFY_ACK, | |
2843 | notify_id, 0, 0); | |
2844 | rbd_osd_req_format_read(obj_request); | |
2845 | ||
2846 | ret = rbd_obj_request_submit(osdc, obj_request); | |
2847 | if (ret) | |
2848 | goto out; | |
2849 | ret = rbd_obj_request_wait(obj_request); | |
2850 | out: | |
2851 | rbd_obj_request_put(obj_request); | |
2852 | ||
2853 | return ret; | |
2854 | } | |
2855 | ||
2856 | static void rbd_watch_cb(u64 ver, u64 notify_id, u8 opcode, void *data) | |
2857 | { | |
2858 | struct rbd_device *rbd_dev = (struct rbd_device *)data; | |
2859 | int ret; | |
2860 | ||
2861 | if (!rbd_dev) | |
2862 | return; | |
2863 | ||
2864 | dout("%s: \"%s\" notify_id %llu opcode %u\n", __func__, | |
2865 | rbd_dev->header_name, (unsigned long long)notify_id, | |
2866 | (unsigned int)opcode); | |
2867 | ret = rbd_dev_refresh(rbd_dev); | |
2868 | if (ret) | |
2869 | rbd_warn(rbd_dev, "header refresh error (%d)\n", ret); | |
2870 | ||
2871 | rbd_obj_notify_ack_sync(rbd_dev, notify_id); | |
2872 | } | |
2873 | ||
2874 | /* | |
2875 | * Request sync osd watch/unwatch. The value of "start" determines | |
2876 | * whether a watch request is being initiated or torn down. | |
2877 | */ | |
2878 | static int __rbd_dev_header_watch_sync(struct rbd_device *rbd_dev, bool start) | |
2879 | { | |
2880 | struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; | |
2881 | struct rbd_obj_request *obj_request; | |
2882 | int ret; | |
2883 | ||
2884 | rbd_assert(start ^ !!rbd_dev->watch_event); | |
2885 | rbd_assert(start ^ !!rbd_dev->watch_request); | |
2886 | ||
2887 | if (start) { | |
2888 | ret = ceph_osdc_create_event(osdc, rbd_watch_cb, rbd_dev, | |
2889 | &rbd_dev->watch_event); | |
2890 | if (ret < 0) | |
2891 | return ret; | |
2892 | rbd_assert(rbd_dev->watch_event != NULL); | |
2893 | } | |
2894 | ||
2895 | ret = -ENOMEM; | |
2896 | obj_request = rbd_obj_request_create(rbd_dev->header_name, 0, 0, | |
2897 | OBJ_REQUEST_NODATA); | |
2898 | if (!obj_request) | |
2899 | goto out_cancel; | |
2900 | ||
2901 | obj_request->osd_req = rbd_osd_req_create(rbd_dev, true, 1, | |
2902 | obj_request); | |
2903 | if (!obj_request->osd_req) | |
2904 | goto out_cancel; | |
2905 | ||
2906 | if (start) | |
2907 | ceph_osdc_set_request_linger(osdc, obj_request->osd_req); | |
2908 | else | |
2909 | ceph_osdc_unregister_linger_request(osdc, | |
2910 | rbd_dev->watch_request->osd_req); | |
2911 | ||
2912 | osd_req_op_watch_init(obj_request->osd_req, 0, CEPH_OSD_OP_WATCH, | |
2913 | rbd_dev->watch_event->cookie, 0, start ? 1 : 0); | |
2914 | rbd_osd_req_format_write(obj_request); | |
2915 | ||
2916 | ret = rbd_obj_request_submit(osdc, obj_request); | |
2917 | if (ret) | |
2918 | goto out_cancel; | |
2919 | ret = rbd_obj_request_wait(obj_request); | |
2920 | if (ret) | |
2921 | goto out_cancel; | |
2922 | ret = obj_request->result; | |
2923 | if (ret) | |
2924 | goto out_cancel; | |
2925 | ||
2926 | /* | |
2927 | * A watch request is set to linger, so the underlying osd | |
2928 | * request won't go away until we unregister it. We retain | |
2929 | * a pointer to the object request during that time (in | |
2930 | * rbd_dev->watch_request), so we'll keep a reference to | |
2931 | * it. We'll drop that reference (below) after we've | |
2932 | * unregistered it. | |
2933 | */ | |
2934 | if (start) { | |
2935 | rbd_dev->watch_request = obj_request; | |
2936 | ||
2937 | return 0; | |
2938 | } | |
2939 | ||
2940 | /* We have successfully torn down the watch request */ | |
2941 | ||
2942 | rbd_obj_request_put(rbd_dev->watch_request); | |
2943 | rbd_dev->watch_request = NULL; | |
2944 | out_cancel: | |
2945 | /* Cancel the event if we're tearing down, or on error */ | |
2946 | ceph_osdc_cancel_event(rbd_dev->watch_event); | |
2947 | rbd_dev->watch_event = NULL; | |
2948 | if (obj_request) | |
2949 | rbd_obj_request_put(obj_request); | |
2950 | ||
2951 | return ret; | |
2952 | } | |
2953 | ||
2954 | static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev) | |
2955 | { | |
2956 | return __rbd_dev_header_watch_sync(rbd_dev, true); | |
2957 | } | |
2958 | ||
2959 | static void rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev) | |
2960 | { | |
2961 | int ret; | |
2962 | ||
2963 | ret = __rbd_dev_header_watch_sync(rbd_dev, false); | |
2964 | if (ret) { | |
2965 | rbd_warn(rbd_dev, "unable to tear down watch request: %d\n", | |
2966 | ret); | |
2967 | } | |
2968 | } | |
2969 | ||
2970 | /* | |
2971 | * Synchronous osd object method call. Returns the number of bytes | |
2972 | * returned in the outbound buffer, or a negative error code. | |
2973 | */ | |
2974 | static int rbd_obj_method_sync(struct rbd_device *rbd_dev, | |
2975 | const char *object_name, | |
2976 | const char *class_name, | |
2977 | const char *method_name, | |
2978 | const void *outbound, | |
2979 | size_t outbound_size, | |
2980 | void *inbound, | |
2981 | size_t inbound_size) | |
2982 | { | |
2983 | struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; | |
2984 | struct rbd_obj_request *obj_request; | |
2985 | struct page **pages; | |
2986 | u32 page_count; | |
2987 | int ret; | |
2988 | ||
2989 | /* | |
2990 | * Method calls are ultimately read operations. The result | |
2991 | * should placed into the inbound buffer provided. They | |
2992 | * also supply outbound data--parameters for the object | |
2993 | * method. Currently if this is present it will be a | |
2994 | * snapshot id. | |
2995 | */ | |
2996 | page_count = (u32)calc_pages_for(0, inbound_size); | |
2997 | pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); | |
2998 | if (IS_ERR(pages)) | |
2999 | return PTR_ERR(pages); | |
3000 | ||
3001 | ret = -ENOMEM; | |
3002 | obj_request = rbd_obj_request_create(object_name, 0, inbound_size, | |
3003 | OBJ_REQUEST_PAGES); | |
3004 | if (!obj_request) | |
3005 | goto out; | |
3006 | ||
3007 | obj_request->pages = pages; | |
3008 | obj_request->page_count = page_count; | |
3009 | ||
3010 | obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1, | |
3011 | obj_request); | |
3012 | if (!obj_request->osd_req) | |
3013 | goto out; | |
3014 | ||
3015 | osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL, | |
3016 | class_name, method_name); | |
3017 | if (outbound_size) { | |
3018 | struct ceph_pagelist *pagelist; | |
3019 | ||
3020 | pagelist = kmalloc(sizeof (*pagelist), GFP_NOFS); | |
3021 | if (!pagelist) | |
3022 | goto out; | |
3023 | ||
3024 | ceph_pagelist_init(pagelist); | |
3025 | ceph_pagelist_append(pagelist, outbound, outbound_size); | |
3026 | osd_req_op_cls_request_data_pagelist(obj_request->osd_req, 0, | |
3027 | pagelist); | |
3028 | } | |
3029 | osd_req_op_cls_response_data_pages(obj_request->osd_req, 0, | |
3030 | obj_request->pages, inbound_size, | |
3031 | 0, false, false); | |
3032 | rbd_osd_req_format_read(obj_request); | |
3033 | ||
3034 | ret = rbd_obj_request_submit(osdc, obj_request); | |
3035 | if (ret) | |
3036 | goto out; | |
3037 | ret = rbd_obj_request_wait(obj_request); | |
3038 | if (ret) | |
3039 | goto out; | |
3040 | ||
3041 | ret = obj_request->result; | |
3042 | if (ret < 0) | |
3043 | goto out; | |
3044 | ||
3045 | rbd_assert(obj_request->xferred < (u64)INT_MAX); | |
3046 | ret = (int)obj_request->xferred; | |
3047 | ceph_copy_from_page_vector(pages, inbound, 0, obj_request->xferred); | |
3048 | out: | |
3049 | if (obj_request) | |
3050 | rbd_obj_request_put(obj_request); | |
3051 | else | |
3052 | ceph_release_page_vector(pages, page_count); | |
3053 | ||
3054 | return ret; | |
3055 | } | |
3056 | ||
3057 | static void rbd_request_fn(struct request_queue *q) | |
3058 | __releases(q->queue_lock) __acquires(q->queue_lock) | |
3059 | { | |
3060 | struct rbd_device *rbd_dev = q->queuedata; | |
3061 | bool read_only = rbd_dev->mapping.read_only; | |
3062 | struct request *rq; | |
3063 | int result; | |
3064 | ||
3065 | while ((rq = blk_fetch_request(q))) { | |
3066 | bool write_request = rq_data_dir(rq) == WRITE; | |
3067 | struct rbd_img_request *img_request; | |
3068 | u64 offset; | |
3069 | u64 length; | |
3070 | ||
3071 | /* Ignore any non-FS requests that filter through. */ | |
3072 | ||
3073 | if (rq->cmd_type != REQ_TYPE_FS) { | |
3074 | dout("%s: non-fs request type %d\n", __func__, | |
3075 | (int) rq->cmd_type); | |
3076 | __blk_end_request_all(rq, 0); | |
3077 | continue; | |
3078 | } | |
3079 | ||
3080 | /* Ignore/skip any zero-length requests */ | |
3081 | ||
3082 | offset = (u64) blk_rq_pos(rq) << SECTOR_SHIFT; | |
3083 | length = (u64) blk_rq_bytes(rq); | |
3084 | ||
3085 | if (!length) { | |
3086 | dout("%s: zero-length request\n", __func__); | |
3087 | __blk_end_request_all(rq, 0); | |
3088 | continue; | |
3089 | } | |
3090 | ||
3091 | spin_unlock_irq(q->queue_lock); | |
3092 | ||
3093 | /* Disallow writes to a read-only device */ | |
3094 | ||
3095 | if (write_request) { | |
3096 | result = -EROFS; | |
3097 | if (read_only) | |
3098 | goto end_request; | |
3099 | rbd_assert(rbd_dev->spec->snap_id == CEPH_NOSNAP); | |
3100 | } | |
3101 | ||
3102 | /* | |
3103 | * Quit early if the mapped snapshot no longer | |
3104 | * exists. It's still possible the snapshot will | |
3105 | * have disappeared by the time our request arrives | |
3106 | * at the osd, but there's no sense in sending it if | |
3107 | * we already know. | |
3108 | */ | |
3109 | if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) { | |
3110 | dout("request for non-existent snapshot"); | |
3111 | rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP); | |
3112 | result = -ENXIO; | |
3113 | goto end_request; | |
3114 | } | |
3115 | ||
3116 | result = -EINVAL; | |
3117 | if (offset && length > U64_MAX - offset + 1) { | |
3118 | rbd_warn(rbd_dev, "bad request range (%llu~%llu)\n", | |
3119 | offset, length); | |
3120 | goto end_request; /* Shouldn't happen */ | |
3121 | } | |
3122 | ||
3123 | result = -EIO; | |
3124 | if (offset + length > rbd_dev->mapping.size) { | |
3125 | rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)\n", | |
3126 | offset, length, rbd_dev->mapping.size); | |
3127 | goto end_request; | |
3128 | } | |
3129 | ||
3130 | result = -ENOMEM; | |
3131 | img_request = rbd_img_request_create(rbd_dev, offset, length, | |
3132 | write_request); | |
3133 | if (!img_request) | |
3134 | goto end_request; | |
3135 | ||
3136 | img_request->rq = rq; | |
3137 | ||
3138 | result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO, | |
3139 | rq->bio); | |
3140 | if (!result) | |
3141 | result = rbd_img_request_submit(img_request); | |
3142 | if (result) | |
3143 | rbd_img_request_put(img_request); | |
3144 | end_request: | |
3145 | spin_lock_irq(q->queue_lock); | |
3146 | if (result < 0) { | |
3147 | rbd_warn(rbd_dev, "%s %llx at %llx result %d\n", | |
3148 | write_request ? "write" : "read", | |
3149 | length, offset, result); | |
3150 | ||
3151 | __blk_end_request_all(rq, result); | |
3152 | } | |
3153 | } | |
3154 | } | |
3155 | ||
3156 | /* | |
3157 | * a queue callback. Makes sure that we don't create a bio that spans across | |
3158 | * multiple osd objects. One exception would be with a single page bios, | |
3159 | * which we handle later at bio_chain_clone_range() | |
3160 | */ | |
3161 | static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd, | |
3162 | struct bio_vec *bvec) | |
3163 | { | |
3164 | struct rbd_device *rbd_dev = q->queuedata; | |
3165 | sector_t sector_offset; | |
3166 | sector_t sectors_per_obj; | |
3167 | sector_t obj_sector_offset; | |
3168 | int ret; | |
3169 | ||
3170 | /* | |
3171 | * Find how far into its rbd object the partition-relative | |
3172 | * bio start sector is to offset relative to the enclosing | |
3173 | * device. | |
3174 | */ | |
3175 | sector_offset = get_start_sect(bmd->bi_bdev) + bmd->bi_sector; | |
3176 | sectors_per_obj = 1 << (rbd_dev->header.obj_order - SECTOR_SHIFT); | |
3177 | obj_sector_offset = sector_offset & (sectors_per_obj - 1); | |
3178 | ||
3179 | /* | |
3180 | * Compute the number of bytes from that offset to the end | |
3181 | * of the object. Account for what's already used by the bio. | |
3182 | */ | |
3183 | ret = (int) (sectors_per_obj - obj_sector_offset) << SECTOR_SHIFT; | |
3184 | if (ret > bmd->bi_size) | |
3185 | ret -= bmd->bi_size; | |
3186 | else | |
3187 | ret = 0; | |
3188 | ||
3189 | /* | |
3190 | * Don't send back more than was asked for. And if the bio | |
3191 | * was empty, let the whole thing through because: "Note | |
3192 | * that a block device *must* allow a single page to be | |
3193 | * added to an empty bio." | |
3194 | */ | |
3195 | rbd_assert(bvec->bv_len <= PAGE_SIZE); | |
3196 | if (ret > (int) bvec->bv_len || !bmd->bi_size) | |
3197 | ret = (int) bvec->bv_len; | |
3198 | ||
3199 | return ret; | |
3200 | } | |
3201 | ||
3202 | static void rbd_free_disk(struct rbd_device *rbd_dev) | |
3203 | { | |
3204 | struct gendisk *disk = rbd_dev->disk; | |
3205 | ||
3206 | if (!disk) | |
3207 | return; | |
3208 | ||
3209 | rbd_dev->disk = NULL; | |
3210 | if (disk->flags & GENHD_FL_UP) { | |
3211 | del_gendisk(disk); | |
3212 | if (disk->queue) | |
3213 | blk_cleanup_queue(disk->queue); | |
3214 | } | |
3215 | put_disk(disk); | |
3216 | } | |
3217 | ||
3218 | static int rbd_obj_read_sync(struct rbd_device *rbd_dev, | |
3219 | const char *object_name, | |
3220 | u64 offset, u64 length, void *buf) | |
3221 | ||
3222 | { | |
3223 | struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; | |
3224 | struct rbd_obj_request *obj_request; | |
3225 | struct page **pages = NULL; | |
3226 | u32 page_count; | |
3227 | size_t size; | |
3228 | int ret; | |
3229 | ||
3230 | page_count = (u32) calc_pages_for(offset, length); | |
3231 | pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); | |
3232 | if (IS_ERR(pages)) | |
3233 | ret = PTR_ERR(pages); | |
3234 | ||
3235 | ret = -ENOMEM; | |
3236 | obj_request = rbd_obj_request_create(object_name, offset, length, | |
3237 | OBJ_REQUEST_PAGES); | |
3238 | if (!obj_request) | |
3239 | goto out; | |
3240 | ||
3241 | obj_request->pages = pages; | |
3242 | obj_request->page_count = page_count; | |
3243 | ||
3244 | obj_request->osd_req = rbd_osd_req_create(rbd_dev, false, 1, | |
3245 | obj_request); | |
3246 | if (!obj_request->osd_req) | |
3247 | goto out; | |
3248 | ||
3249 | osd_req_op_extent_init(obj_request->osd_req, 0, CEPH_OSD_OP_READ, | |
3250 | offset, length, 0, 0); | |
3251 | osd_req_op_extent_osd_data_pages(obj_request->osd_req, 0, | |
3252 | obj_request->pages, | |
3253 | obj_request->length, | |
3254 | obj_request->offset & ~PAGE_MASK, | |
3255 | false, false); | |
3256 | rbd_osd_req_format_read(obj_request); | |
3257 | ||
3258 | ret = rbd_obj_request_submit(osdc, obj_request); | |
3259 | if (ret) | |
3260 | goto out; | |
3261 | ret = rbd_obj_request_wait(obj_request); | |
3262 | if (ret) | |
3263 | goto out; | |
3264 | ||
3265 | ret = obj_request->result; | |
3266 | if (ret < 0) | |
3267 | goto out; | |
3268 | ||
3269 | rbd_assert(obj_request->xferred <= (u64) SIZE_MAX); | |
3270 | size = (size_t) obj_request->xferred; | |
3271 | ceph_copy_from_page_vector(pages, buf, 0, size); | |
3272 | rbd_assert(size <= (size_t)INT_MAX); | |
3273 | ret = (int)size; | |
3274 | out: | |
3275 | if (obj_request) | |
3276 | rbd_obj_request_put(obj_request); | |
3277 | else | |
3278 | ceph_release_page_vector(pages, page_count); | |
3279 | ||
3280 | return ret; | |
3281 | } | |
3282 | ||
3283 | /* | |
3284 | * Read the complete header for the given rbd device. On successful | |
3285 | * return, the rbd_dev->header field will contain up-to-date | |
3286 | * information about the image. | |
3287 | */ | |
3288 | static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev) | |
3289 | { | |
3290 | struct rbd_image_header_ondisk *ondisk = NULL; | |
3291 | u32 snap_count = 0; | |
3292 | u64 names_size = 0; | |
3293 | u32 want_count; | |
3294 | int ret; | |
3295 | ||
3296 | /* | |
3297 | * The complete header will include an array of its 64-bit | |
3298 | * snapshot ids, followed by the names of those snapshots as | |
3299 | * a contiguous block of NUL-terminated strings. Note that | |
3300 | * the number of snapshots could change by the time we read | |
3301 | * it in, in which case we re-read it. | |
3302 | */ | |
3303 | do { | |
3304 | size_t size; | |
3305 | ||
3306 | kfree(ondisk); | |
3307 | ||
3308 | size = sizeof (*ondisk); | |
3309 | size += snap_count * sizeof (struct rbd_image_snap_ondisk); | |
3310 | size += names_size; | |
3311 | ondisk = kmalloc(size, GFP_KERNEL); | |
3312 | if (!ondisk) | |
3313 | return -ENOMEM; | |
3314 | ||
3315 | ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name, | |
3316 | 0, size, ondisk); | |
3317 | if (ret < 0) | |
3318 | goto out; | |
3319 | if ((size_t)ret < size) { | |
3320 | ret = -ENXIO; | |
3321 | rbd_warn(rbd_dev, "short header read (want %zd got %d)", | |
3322 | size, ret); | |
3323 | goto out; | |
3324 | } | |
3325 | if (!rbd_dev_ondisk_valid(ondisk)) { | |
3326 | ret = -ENXIO; | |
3327 | rbd_warn(rbd_dev, "invalid header"); | |
3328 | goto out; | |
3329 | } | |
3330 | ||
3331 | names_size = le64_to_cpu(ondisk->snap_names_len); | |
3332 | want_count = snap_count; | |
3333 | snap_count = le32_to_cpu(ondisk->snap_count); | |
3334 | } while (snap_count != want_count); | |
3335 | ||
3336 | ret = rbd_header_from_disk(rbd_dev, ondisk); | |
3337 | out: | |
3338 | kfree(ondisk); | |
3339 | ||
3340 | return ret; | |
3341 | } | |
3342 | ||
3343 | /* | |
3344 | * Clear the rbd device's EXISTS flag if the snapshot it's mapped to | |
3345 | * has disappeared from the (just updated) snapshot context. | |
3346 | */ | |
3347 | static void rbd_exists_validate(struct rbd_device *rbd_dev) | |
3348 | { | |
3349 | u64 snap_id; | |
3350 | ||
3351 | if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) | |
3352 | return; | |
3353 | ||
3354 | snap_id = rbd_dev->spec->snap_id; | |
3355 | if (snap_id == CEPH_NOSNAP) | |
3356 | return; | |
3357 | ||
3358 | if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX) | |
3359 | clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); | |
3360 | } | |
3361 | ||
3362 | static void rbd_dev_update_size(struct rbd_device *rbd_dev) | |
3363 | { | |
3364 | sector_t size; | |
3365 | bool removing; | |
3366 | ||
3367 | /* | |
3368 | * Don't hold the lock while doing disk operations, | |
3369 | * or lock ordering will conflict with the bdev mutex via: | |
3370 | * rbd_add() -> blkdev_get() -> rbd_open() | |
3371 | */ | |
3372 | spin_lock_irq(&rbd_dev->lock); | |
3373 | removing = test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags); | |
3374 | spin_unlock_irq(&rbd_dev->lock); | |
3375 | /* | |
3376 | * If the device is being removed, rbd_dev->disk has | |
3377 | * been destroyed, so don't try to update its size | |
3378 | */ | |
3379 | if (!removing) { | |
3380 | size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE; | |
3381 | dout("setting size to %llu sectors", (unsigned long long)size); | |
3382 | set_capacity(rbd_dev->disk, size); | |
3383 | revalidate_disk(rbd_dev->disk); | |
3384 | } | |
3385 | } | |
3386 | ||
3387 | static int rbd_dev_refresh(struct rbd_device *rbd_dev) | |
3388 | { | |
3389 | u64 mapping_size; | |
3390 | int ret; | |
3391 | ||
3392 | rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); | |
3393 | down_write(&rbd_dev->header_rwsem); | |
3394 | mapping_size = rbd_dev->mapping.size; | |
3395 | if (rbd_dev->image_format == 1) | |
3396 | ret = rbd_dev_v1_header_info(rbd_dev); | |
3397 | else | |
3398 | ret = rbd_dev_v2_header_info(rbd_dev); | |
3399 | ||
3400 | /* If it's a mapped snapshot, validate its EXISTS flag */ | |
3401 | ||
3402 | rbd_exists_validate(rbd_dev); | |
3403 | up_write(&rbd_dev->header_rwsem); | |
3404 | ||
3405 | if (mapping_size != rbd_dev->mapping.size) { | |
3406 | rbd_dev_update_size(rbd_dev); | |
3407 | } | |
3408 | ||
3409 | return ret; | |
3410 | } | |
3411 | ||
3412 | static int rbd_init_disk(struct rbd_device *rbd_dev) | |
3413 | { | |
3414 | struct gendisk *disk; | |
3415 | struct request_queue *q; | |
3416 | u64 segment_size; | |
3417 | ||
3418 | /* create gendisk info */ | |
3419 | disk = alloc_disk(single_major ? | |
3420 | (1 << RBD_SINGLE_MAJOR_PART_SHIFT) : | |
3421 | RBD_MINORS_PER_MAJOR); | |
3422 | if (!disk) | |
3423 | return -ENOMEM; | |
3424 | ||
3425 | snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d", | |
3426 | rbd_dev->dev_id); | |
3427 | disk->major = rbd_dev->major; | |
3428 | disk->first_minor = rbd_dev->minor; | |
3429 | if (single_major) | |
3430 | disk->flags |= GENHD_FL_EXT_DEVT; | |
3431 | disk->fops = &rbd_bd_ops; | |
3432 | disk->private_data = rbd_dev; | |
3433 | ||
3434 | q = blk_init_queue(rbd_request_fn, &rbd_dev->lock); | |
3435 | if (!q) | |
3436 | goto out_disk; | |
3437 | ||
3438 | /* We use the default size, but let's be explicit about it. */ | |
3439 | blk_queue_physical_block_size(q, SECTOR_SIZE); | |
3440 | ||
3441 | /* set io sizes to object size */ | |
3442 | segment_size = rbd_obj_bytes(&rbd_dev->header); | |
3443 | blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE); | |
3444 | blk_queue_max_segment_size(q, segment_size); | |
3445 | blk_queue_io_min(q, segment_size); | |
3446 | blk_queue_io_opt(q, segment_size); | |
3447 | ||
3448 | blk_queue_merge_bvec(q, rbd_merge_bvec); | |
3449 | disk->queue = q; | |
3450 | ||
3451 | q->queuedata = rbd_dev; | |
3452 | ||
3453 | rbd_dev->disk = disk; | |
3454 | ||
3455 | return 0; | |
3456 | out_disk: | |
3457 | put_disk(disk); | |
3458 | ||
3459 | return -ENOMEM; | |
3460 | } | |
3461 | ||
3462 | /* | |
3463 | sysfs | |
3464 | */ | |
3465 | ||
3466 | static struct rbd_device *dev_to_rbd_dev(struct device *dev) | |
3467 | { | |
3468 | return container_of(dev, struct rbd_device, dev); | |
3469 | } | |
3470 | ||
3471 | static ssize_t rbd_size_show(struct device *dev, | |
3472 | struct device_attribute *attr, char *buf) | |
3473 | { | |
3474 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3475 | ||
3476 | return sprintf(buf, "%llu\n", | |
3477 | (unsigned long long)rbd_dev->mapping.size); | |
3478 | } | |
3479 | ||
3480 | /* | |
3481 | * Note this shows the features for whatever's mapped, which is not | |
3482 | * necessarily the base image. | |
3483 | */ | |
3484 | static ssize_t rbd_features_show(struct device *dev, | |
3485 | struct device_attribute *attr, char *buf) | |
3486 | { | |
3487 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3488 | ||
3489 | return sprintf(buf, "0x%016llx\n", | |
3490 | (unsigned long long)rbd_dev->mapping.features); | |
3491 | } | |
3492 | ||
3493 | static ssize_t rbd_major_show(struct device *dev, | |
3494 | struct device_attribute *attr, char *buf) | |
3495 | { | |
3496 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3497 | ||
3498 | if (rbd_dev->major) | |
3499 | return sprintf(buf, "%d\n", rbd_dev->major); | |
3500 | ||
3501 | return sprintf(buf, "(none)\n"); | |
3502 | } | |
3503 | ||
3504 | static ssize_t rbd_minor_show(struct device *dev, | |
3505 | struct device_attribute *attr, char *buf) | |
3506 | { | |
3507 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3508 | ||
3509 | return sprintf(buf, "%d\n", rbd_dev->minor); | |
3510 | } | |
3511 | ||
3512 | static ssize_t rbd_client_id_show(struct device *dev, | |
3513 | struct device_attribute *attr, char *buf) | |
3514 | { | |
3515 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3516 | ||
3517 | return sprintf(buf, "client%lld\n", | |
3518 | ceph_client_id(rbd_dev->rbd_client->client)); | |
3519 | } | |
3520 | ||
3521 | static ssize_t rbd_pool_show(struct device *dev, | |
3522 | struct device_attribute *attr, char *buf) | |
3523 | { | |
3524 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3525 | ||
3526 | return sprintf(buf, "%s\n", rbd_dev->spec->pool_name); | |
3527 | } | |
3528 | ||
3529 | static ssize_t rbd_pool_id_show(struct device *dev, | |
3530 | struct device_attribute *attr, char *buf) | |
3531 | { | |
3532 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3533 | ||
3534 | return sprintf(buf, "%llu\n", | |
3535 | (unsigned long long) rbd_dev->spec->pool_id); | |
3536 | } | |
3537 | ||
3538 | static ssize_t rbd_name_show(struct device *dev, | |
3539 | struct device_attribute *attr, char *buf) | |
3540 | { | |
3541 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3542 | ||
3543 | if (rbd_dev->spec->image_name) | |
3544 | return sprintf(buf, "%s\n", rbd_dev->spec->image_name); | |
3545 | ||
3546 | return sprintf(buf, "(unknown)\n"); | |
3547 | } | |
3548 | ||
3549 | static ssize_t rbd_image_id_show(struct device *dev, | |
3550 | struct device_attribute *attr, char *buf) | |
3551 | { | |
3552 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3553 | ||
3554 | return sprintf(buf, "%s\n", rbd_dev->spec->image_id); | |
3555 | } | |
3556 | ||
3557 | /* | |
3558 | * Shows the name of the currently-mapped snapshot (or | |
3559 | * RBD_SNAP_HEAD_NAME for the base image). | |
3560 | */ | |
3561 | static ssize_t rbd_snap_show(struct device *dev, | |
3562 | struct device_attribute *attr, | |
3563 | char *buf) | |
3564 | { | |
3565 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3566 | ||
3567 | return sprintf(buf, "%s\n", rbd_dev->spec->snap_name); | |
3568 | } | |
3569 | ||
3570 | /* | |
3571 | * For an rbd v2 image, shows the pool id, image id, and snapshot id | |
3572 | * for the parent image. If there is no parent, simply shows | |
3573 | * "(no parent image)". | |
3574 | */ | |
3575 | static ssize_t rbd_parent_show(struct device *dev, | |
3576 | struct device_attribute *attr, | |
3577 | char *buf) | |
3578 | { | |
3579 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3580 | struct rbd_spec *spec = rbd_dev->parent_spec; | |
3581 | int count; | |
3582 | char *bufp = buf; | |
3583 | ||
3584 | if (!spec) | |
3585 | return sprintf(buf, "(no parent image)\n"); | |
3586 | ||
3587 | count = sprintf(bufp, "pool_id %llu\npool_name %s\n", | |
3588 | (unsigned long long) spec->pool_id, spec->pool_name); | |
3589 | if (count < 0) | |
3590 | return count; | |
3591 | bufp += count; | |
3592 | ||
3593 | count = sprintf(bufp, "image_id %s\nimage_name %s\n", spec->image_id, | |
3594 | spec->image_name ? spec->image_name : "(unknown)"); | |
3595 | if (count < 0) | |
3596 | return count; | |
3597 | bufp += count; | |
3598 | ||
3599 | count = sprintf(bufp, "snap_id %llu\nsnap_name %s\n", | |
3600 | (unsigned long long) spec->snap_id, spec->snap_name); | |
3601 | if (count < 0) | |
3602 | return count; | |
3603 | bufp += count; | |
3604 | ||
3605 | count = sprintf(bufp, "overlap %llu\n", rbd_dev->parent_overlap); | |
3606 | if (count < 0) | |
3607 | return count; | |
3608 | bufp += count; | |
3609 | ||
3610 | return (ssize_t) (bufp - buf); | |
3611 | } | |
3612 | ||
3613 | static ssize_t rbd_image_refresh(struct device *dev, | |
3614 | struct device_attribute *attr, | |
3615 | const char *buf, | |
3616 | size_t size) | |
3617 | { | |
3618 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
3619 | int ret; | |
3620 | ||
3621 | ret = rbd_dev_refresh(rbd_dev); | |
3622 | if (ret) | |
3623 | rbd_warn(rbd_dev, ": manual header refresh error (%d)\n", ret); | |
3624 | ||
3625 | return ret < 0 ? ret : size; | |
3626 | } | |
3627 | ||
3628 | static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL); | |
3629 | static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL); | |
3630 | static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL); | |
3631 | static DEVICE_ATTR(minor, S_IRUGO, rbd_minor_show, NULL); | |
3632 | static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL); | |
3633 | static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL); | |
3634 | static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL); | |
3635 | static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL); | |
3636 | static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL); | |
3637 | static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh); | |
3638 | static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL); | |
3639 | static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL); | |
3640 | ||
3641 | static struct attribute *rbd_attrs[] = { | |
3642 | &dev_attr_size.attr, | |
3643 | &dev_attr_features.attr, | |
3644 | &dev_attr_major.attr, | |
3645 | &dev_attr_minor.attr, | |
3646 | &dev_attr_client_id.attr, | |
3647 | &dev_attr_pool.attr, | |
3648 | &dev_attr_pool_id.attr, | |
3649 | &dev_attr_name.attr, | |
3650 | &dev_attr_image_id.attr, | |
3651 | &dev_attr_current_snap.attr, | |
3652 | &dev_attr_parent.attr, | |
3653 | &dev_attr_refresh.attr, | |
3654 | NULL | |
3655 | }; | |
3656 | ||
3657 | static struct attribute_group rbd_attr_group = { | |
3658 | .attrs = rbd_attrs, | |
3659 | }; | |
3660 | ||
3661 | static const struct attribute_group *rbd_attr_groups[] = { | |
3662 | &rbd_attr_group, | |
3663 | NULL | |
3664 | }; | |
3665 | ||
3666 | static void rbd_sysfs_dev_release(struct device *dev) | |
3667 | { | |
3668 | } | |
3669 | ||
3670 | static struct device_type rbd_device_type = { | |
3671 | .name = "rbd", | |
3672 | .groups = rbd_attr_groups, | |
3673 | .release = rbd_sysfs_dev_release, | |
3674 | }; | |
3675 | ||
3676 | static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec) | |
3677 | { | |
3678 | kref_get(&spec->kref); | |
3679 | ||
3680 | return spec; | |
3681 | } | |
3682 | ||
3683 | static void rbd_spec_free(struct kref *kref); | |
3684 | static void rbd_spec_put(struct rbd_spec *spec) | |
3685 | { | |
3686 | if (spec) | |
3687 | kref_put(&spec->kref, rbd_spec_free); | |
3688 | } | |
3689 | ||
3690 | static struct rbd_spec *rbd_spec_alloc(void) | |
3691 | { | |
3692 | struct rbd_spec *spec; | |
3693 | ||
3694 | spec = kzalloc(sizeof (*spec), GFP_KERNEL); | |
3695 | if (!spec) | |
3696 | return NULL; | |
3697 | kref_init(&spec->kref); | |
3698 | ||
3699 | return spec; | |
3700 | } | |
3701 | ||
3702 | static void rbd_spec_free(struct kref *kref) | |
3703 | { | |
3704 | struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref); | |
3705 | ||
3706 | kfree(spec->pool_name); | |
3707 | kfree(spec->image_id); | |
3708 | kfree(spec->image_name); | |
3709 | kfree(spec->snap_name); | |
3710 | kfree(spec); | |
3711 | } | |
3712 | ||
3713 | static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc, | |
3714 | struct rbd_spec *spec) | |
3715 | { | |
3716 | struct rbd_device *rbd_dev; | |
3717 | ||
3718 | rbd_dev = kzalloc(sizeof (*rbd_dev), GFP_KERNEL); | |
3719 | if (!rbd_dev) | |
3720 | return NULL; | |
3721 | ||
3722 | spin_lock_init(&rbd_dev->lock); | |
3723 | rbd_dev->flags = 0; | |
3724 | atomic_set(&rbd_dev->parent_ref, 0); | |
3725 | INIT_LIST_HEAD(&rbd_dev->node); | |
3726 | init_rwsem(&rbd_dev->header_rwsem); | |
3727 | ||
3728 | rbd_dev->spec = spec; | |
3729 | rbd_dev->rbd_client = rbdc; | |
3730 | ||
3731 | /* Initialize the layout used for all rbd requests */ | |
3732 | ||
3733 | rbd_dev->layout.fl_stripe_unit = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER); | |
3734 | rbd_dev->layout.fl_stripe_count = cpu_to_le32(1); | |
3735 | rbd_dev->layout.fl_object_size = cpu_to_le32(1 << RBD_MAX_OBJ_ORDER); | |
3736 | rbd_dev->layout.fl_pg_pool = cpu_to_le32((u32) spec->pool_id); | |
3737 | ||
3738 | return rbd_dev; | |
3739 | } | |
3740 | ||
3741 | static void rbd_dev_destroy(struct rbd_device *rbd_dev) | |
3742 | { | |
3743 | rbd_put_client(rbd_dev->rbd_client); | |
3744 | rbd_spec_put(rbd_dev->spec); | |
3745 | kfree(rbd_dev); | |
3746 | } | |
3747 | ||
3748 | /* | |
3749 | * Get the size and object order for an image snapshot, or if | |
3750 | * snap_id is CEPH_NOSNAP, gets this information for the base | |
3751 | * image. | |
3752 | */ | |
3753 | static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id, | |
3754 | u8 *order, u64 *snap_size) | |
3755 | { | |
3756 | __le64 snapid = cpu_to_le64(snap_id); | |
3757 | int ret; | |
3758 | struct { | |
3759 | u8 order; | |
3760 | __le64 size; | |
3761 | } __attribute__ ((packed)) size_buf = { 0 }; | |
3762 | ||
3763 | ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, | |
3764 | "rbd", "get_size", | |
3765 | &snapid, sizeof (snapid), | |
3766 | &size_buf, sizeof (size_buf)); | |
3767 | dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); | |
3768 | if (ret < 0) | |
3769 | return ret; | |
3770 | if (ret < sizeof (size_buf)) | |
3771 | return -ERANGE; | |
3772 | ||
3773 | if (order) { | |
3774 | *order = size_buf.order; | |
3775 | dout(" order %u", (unsigned int)*order); | |
3776 | } | |
3777 | *snap_size = le64_to_cpu(size_buf.size); | |
3778 | ||
3779 | dout(" snap_id 0x%016llx snap_size = %llu\n", | |
3780 | (unsigned long long)snap_id, | |
3781 | (unsigned long long)*snap_size); | |
3782 | ||
3783 | return 0; | |
3784 | } | |
3785 | ||
3786 | static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev) | |
3787 | { | |
3788 | return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP, | |
3789 | &rbd_dev->header.obj_order, | |
3790 | &rbd_dev->header.image_size); | |
3791 | } | |
3792 | ||
3793 | static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev) | |
3794 | { | |
3795 | void *reply_buf; | |
3796 | int ret; | |
3797 | void *p; | |
3798 | ||
3799 | reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL); | |
3800 | if (!reply_buf) | |
3801 | return -ENOMEM; | |
3802 | ||
3803 | ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, | |
3804 | "rbd", "get_object_prefix", NULL, 0, | |
3805 | reply_buf, RBD_OBJ_PREFIX_LEN_MAX); | |
3806 | dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); | |
3807 | if (ret < 0) | |
3808 | goto out; | |
3809 | ||
3810 | p = reply_buf; | |
3811 | rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p, | |
3812 | p + ret, NULL, GFP_NOIO); | |
3813 | ret = 0; | |
3814 | ||
3815 | if (IS_ERR(rbd_dev->header.object_prefix)) { | |
3816 | ret = PTR_ERR(rbd_dev->header.object_prefix); | |
3817 | rbd_dev->header.object_prefix = NULL; | |
3818 | } else { | |
3819 | dout(" object_prefix = %s\n", rbd_dev->header.object_prefix); | |
3820 | } | |
3821 | out: | |
3822 | kfree(reply_buf); | |
3823 | ||
3824 | return ret; | |
3825 | } | |
3826 | ||
3827 | static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id, | |
3828 | u64 *snap_features) | |
3829 | { | |
3830 | __le64 snapid = cpu_to_le64(snap_id); | |
3831 | struct { | |
3832 | __le64 features; | |
3833 | __le64 incompat; | |
3834 | } __attribute__ ((packed)) features_buf = { 0 }; | |
3835 | u64 incompat; | |
3836 | int ret; | |
3837 | ||
3838 | ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, | |
3839 | "rbd", "get_features", | |
3840 | &snapid, sizeof (snapid), | |
3841 | &features_buf, sizeof (features_buf)); | |
3842 | dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); | |
3843 | if (ret < 0) | |
3844 | return ret; | |
3845 | if (ret < sizeof (features_buf)) | |
3846 | return -ERANGE; | |
3847 | ||
3848 | incompat = le64_to_cpu(features_buf.incompat); | |
3849 | if (incompat & ~RBD_FEATURES_SUPPORTED) | |
3850 | return -ENXIO; | |
3851 | ||
3852 | *snap_features = le64_to_cpu(features_buf.features); | |
3853 | ||
3854 | dout(" snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n", | |
3855 | (unsigned long long)snap_id, | |
3856 | (unsigned long long)*snap_features, | |
3857 | (unsigned long long)le64_to_cpu(features_buf.incompat)); | |
3858 | ||
3859 | return 0; | |
3860 | } | |
3861 | ||
3862 | static int rbd_dev_v2_features(struct rbd_device *rbd_dev) | |
3863 | { | |
3864 | return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP, | |
3865 | &rbd_dev->header.features); | |
3866 | } | |
3867 | ||
3868 | static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev) | |
3869 | { | |
3870 | struct rbd_spec *parent_spec; | |
3871 | size_t size; | |
3872 | void *reply_buf = NULL; | |
3873 | __le64 snapid; | |
3874 | void *p; | |
3875 | void *end; | |
3876 | u64 pool_id; | |
3877 | char *image_id; | |
3878 | u64 snap_id; | |
3879 | u64 overlap; | |
3880 | int ret; | |
3881 | ||
3882 | parent_spec = rbd_spec_alloc(); | |
3883 | if (!parent_spec) | |
3884 | return -ENOMEM; | |
3885 | ||
3886 | size = sizeof (__le64) + /* pool_id */ | |
3887 | sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX + /* image_id */ | |
3888 | sizeof (__le64) + /* snap_id */ | |
3889 | sizeof (__le64); /* overlap */ | |
3890 | reply_buf = kmalloc(size, GFP_KERNEL); | |
3891 | if (!reply_buf) { | |
3892 | ret = -ENOMEM; | |
3893 | goto out_err; | |
3894 | } | |
3895 | ||
3896 | snapid = cpu_to_le64(CEPH_NOSNAP); | |
3897 | ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, | |
3898 | "rbd", "get_parent", | |
3899 | &snapid, sizeof (snapid), | |
3900 | reply_buf, size); | |
3901 | dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); | |
3902 | if (ret < 0) | |
3903 | goto out_err; | |
3904 | ||
3905 | p = reply_buf; | |
3906 | end = reply_buf + ret; | |
3907 | ret = -ERANGE; | |
3908 | ceph_decode_64_safe(&p, end, pool_id, out_err); | |
3909 | if (pool_id == CEPH_NOPOOL) { | |
3910 | /* | |
3911 | * Either the parent never existed, or we have | |
3912 | * record of it but the image got flattened so it no | |
3913 | * longer has a parent. When the parent of a | |
3914 | * layered image disappears we immediately set the | |
3915 | * overlap to 0. The effect of this is that all new | |
3916 | * requests will be treated as if the image had no | |
3917 | * parent. | |
3918 | */ | |
3919 | if (rbd_dev->parent_overlap) { | |
3920 | rbd_dev->parent_overlap = 0; | |
3921 | smp_mb(); | |
3922 | rbd_dev_parent_put(rbd_dev); | |
3923 | pr_info("%s: clone image has been flattened\n", | |
3924 | rbd_dev->disk->disk_name); | |
3925 | } | |
3926 | ||
3927 | goto out; /* No parent? No problem. */ | |
3928 | } | |
3929 | ||
3930 | /* The ceph file layout needs to fit pool id in 32 bits */ | |
3931 | ||
3932 | ret = -EIO; | |
3933 | if (pool_id > (u64)U32_MAX) { | |
3934 | rbd_warn(NULL, "parent pool id too large (%llu > %u)\n", | |
3935 | (unsigned long long)pool_id, U32_MAX); | |
3936 | goto out_err; | |
3937 | } | |
3938 | ||
3939 | image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL); | |
3940 | if (IS_ERR(image_id)) { | |
3941 | ret = PTR_ERR(image_id); | |
3942 | goto out_err; | |
3943 | } | |
3944 | ceph_decode_64_safe(&p, end, snap_id, out_err); | |
3945 | ceph_decode_64_safe(&p, end, overlap, out_err); | |
3946 | ||
3947 | /* | |
3948 | * The parent won't change (except when the clone is | |
3949 | * flattened, already handled that). So we only need to | |
3950 | * record the parent spec we have not already done so. | |
3951 | */ | |
3952 | if (!rbd_dev->parent_spec) { | |
3953 | parent_spec->pool_id = pool_id; | |
3954 | parent_spec->image_id = image_id; | |
3955 | parent_spec->snap_id = snap_id; | |
3956 | rbd_dev->parent_spec = parent_spec; | |
3957 | parent_spec = NULL; /* rbd_dev now owns this */ | |
3958 | } | |
3959 | ||
3960 | /* | |
3961 | * We always update the parent overlap. If it's zero we | |
3962 | * treat it specially. | |
3963 | */ | |
3964 | rbd_dev->parent_overlap = overlap; | |
3965 | smp_mb(); | |
3966 | if (!overlap) { | |
3967 | ||
3968 | /* A null parent_spec indicates it's the initial probe */ | |
3969 | ||
3970 | if (parent_spec) { | |
3971 | /* | |
3972 | * The overlap has become zero, so the clone | |
3973 | * must have been resized down to 0 at some | |
3974 | * point. Treat this the same as a flatten. | |
3975 | */ | |
3976 | rbd_dev_parent_put(rbd_dev); | |
3977 | pr_info("%s: clone image now standalone\n", | |
3978 | rbd_dev->disk->disk_name); | |
3979 | } else { | |
3980 | /* | |
3981 | * For the initial probe, if we find the | |
3982 | * overlap is zero we just pretend there was | |
3983 | * no parent image. | |
3984 | */ | |
3985 | rbd_warn(rbd_dev, "ignoring parent of " | |
3986 | "clone with overlap 0\n"); | |
3987 | } | |
3988 | } | |
3989 | out: | |
3990 | ret = 0; | |
3991 | out_err: | |
3992 | kfree(reply_buf); | |
3993 | rbd_spec_put(parent_spec); | |
3994 | ||
3995 | return ret; | |
3996 | } | |
3997 | ||
3998 | static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev) | |
3999 | { | |
4000 | struct { | |
4001 | __le64 stripe_unit; | |
4002 | __le64 stripe_count; | |
4003 | } __attribute__ ((packed)) striping_info_buf = { 0 }; | |
4004 | size_t size = sizeof (striping_info_buf); | |
4005 | void *p; | |
4006 | u64 obj_size; | |
4007 | u64 stripe_unit; | |
4008 | u64 stripe_count; | |
4009 | int ret; | |
4010 | ||
4011 | ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, | |
4012 | "rbd", "get_stripe_unit_count", NULL, 0, | |
4013 | (char *)&striping_info_buf, size); | |
4014 | dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); | |
4015 | if (ret < 0) | |
4016 | return ret; | |
4017 | if (ret < size) | |
4018 | return -ERANGE; | |
4019 | ||
4020 | /* | |
4021 | * We don't actually support the "fancy striping" feature | |
4022 | * (STRIPINGV2) yet, but if the striping sizes are the | |
4023 | * defaults the behavior is the same as before. So find | |
4024 | * out, and only fail if the image has non-default values. | |
4025 | */ | |
4026 | ret = -EINVAL; | |
4027 | obj_size = (u64)1 << rbd_dev->header.obj_order; | |
4028 | p = &striping_info_buf; | |
4029 | stripe_unit = ceph_decode_64(&p); | |
4030 | if (stripe_unit != obj_size) { | |
4031 | rbd_warn(rbd_dev, "unsupported stripe unit " | |
4032 | "(got %llu want %llu)", | |
4033 | stripe_unit, obj_size); | |
4034 | return -EINVAL; | |
4035 | } | |
4036 | stripe_count = ceph_decode_64(&p); | |
4037 | if (stripe_count != 1) { | |
4038 | rbd_warn(rbd_dev, "unsupported stripe count " | |
4039 | "(got %llu want 1)", stripe_count); | |
4040 | return -EINVAL; | |
4041 | } | |
4042 | rbd_dev->header.stripe_unit = stripe_unit; | |
4043 | rbd_dev->header.stripe_count = stripe_count; | |
4044 | ||
4045 | return 0; | |
4046 | } | |
4047 | ||
4048 | static char *rbd_dev_image_name(struct rbd_device *rbd_dev) | |
4049 | { | |
4050 | size_t image_id_size; | |
4051 | char *image_id; | |
4052 | void *p; | |
4053 | void *end; | |
4054 | size_t size; | |
4055 | void *reply_buf = NULL; | |
4056 | size_t len = 0; | |
4057 | char *image_name = NULL; | |
4058 | int ret; | |
4059 | ||
4060 | rbd_assert(!rbd_dev->spec->image_name); | |
4061 | ||
4062 | len = strlen(rbd_dev->spec->image_id); | |
4063 | image_id_size = sizeof (__le32) + len; | |
4064 | image_id = kmalloc(image_id_size, GFP_KERNEL); | |
4065 | if (!image_id) | |
4066 | return NULL; | |
4067 | ||
4068 | p = image_id; | |
4069 | end = image_id + image_id_size; | |
4070 | ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len); | |
4071 | ||
4072 | size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX; | |
4073 | reply_buf = kmalloc(size, GFP_KERNEL); | |
4074 | if (!reply_buf) | |
4075 | goto out; | |
4076 | ||
4077 | ret = rbd_obj_method_sync(rbd_dev, RBD_DIRECTORY, | |
4078 | "rbd", "dir_get_name", | |
4079 | image_id, image_id_size, | |
4080 | reply_buf, size); | |
4081 | if (ret < 0) | |
4082 | goto out; | |
4083 | p = reply_buf; | |
4084 | end = reply_buf + ret; | |
4085 | ||
4086 | image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL); | |
4087 | if (IS_ERR(image_name)) | |
4088 | image_name = NULL; | |
4089 | else | |
4090 | dout("%s: name is %s len is %zd\n", __func__, image_name, len); | |
4091 | out: | |
4092 | kfree(reply_buf); | |
4093 | kfree(image_id); | |
4094 | ||
4095 | return image_name; | |
4096 | } | |
4097 | ||
4098 | static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) | |
4099 | { | |
4100 | struct ceph_snap_context *snapc = rbd_dev->header.snapc; | |
4101 | const char *snap_name; | |
4102 | u32 which = 0; | |
4103 | ||
4104 | /* Skip over names until we find the one we are looking for */ | |
4105 | ||
4106 | snap_name = rbd_dev->header.snap_names; | |
4107 | while (which < snapc->num_snaps) { | |
4108 | if (!strcmp(name, snap_name)) | |
4109 | return snapc->snaps[which]; | |
4110 | snap_name += strlen(snap_name) + 1; | |
4111 | which++; | |
4112 | } | |
4113 | return CEPH_NOSNAP; | |
4114 | } | |
4115 | ||
4116 | static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) | |
4117 | { | |
4118 | struct ceph_snap_context *snapc = rbd_dev->header.snapc; | |
4119 | u32 which; | |
4120 | bool found = false; | |
4121 | u64 snap_id; | |
4122 | ||
4123 | for (which = 0; !found && which < snapc->num_snaps; which++) { | |
4124 | const char *snap_name; | |
4125 | ||
4126 | snap_id = snapc->snaps[which]; | |
4127 | snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id); | |
4128 | if (IS_ERR(snap_name)) { | |
4129 | /* ignore no-longer existing snapshots */ | |
4130 | if (PTR_ERR(snap_name) == -ENOENT) | |
4131 | continue; | |
4132 | else | |
4133 | break; | |
4134 | } | |
4135 | found = !strcmp(name, snap_name); | |
4136 | kfree(snap_name); | |
4137 | } | |
4138 | return found ? snap_id : CEPH_NOSNAP; | |
4139 | } | |
4140 | ||
4141 | /* | |
4142 | * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if | |
4143 | * no snapshot by that name is found, or if an error occurs. | |
4144 | */ | |
4145 | static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name) | |
4146 | { | |
4147 | if (rbd_dev->image_format == 1) | |
4148 | return rbd_v1_snap_id_by_name(rbd_dev, name); | |
4149 | ||
4150 | return rbd_v2_snap_id_by_name(rbd_dev, name); | |
4151 | } | |
4152 | ||
4153 | /* | |
4154 | * When an rbd image has a parent image, it is identified by the | |
4155 | * pool, image, and snapshot ids (not names). This function fills | |
4156 | * in the names for those ids. (It's OK if we can't figure out the | |
4157 | * name for an image id, but the pool and snapshot ids should always | |
4158 | * exist and have names.) All names in an rbd spec are dynamically | |
4159 | * allocated. | |
4160 | * | |
4161 | * When an image being mapped (not a parent) is probed, we have the | |
4162 | * pool name and pool id, image name and image id, and the snapshot | |
4163 | * name. The only thing we're missing is the snapshot id. | |
4164 | */ | |
4165 | static int rbd_dev_spec_update(struct rbd_device *rbd_dev) | |
4166 | { | |
4167 | struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; | |
4168 | struct rbd_spec *spec = rbd_dev->spec; | |
4169 | const char *pool_name; | |
4170 | const char *image_name; | |
4171 | const char *snap_name; | |
4172 | int ret; | |
4173 | ||
4174 | /* | |
4175 | * An image being mapped will have the pool name (etc.), but | |
4176 | * we need to look up the snapshot id. | |
4177 | */ | |
4178 | if (spec->pool_name) { | |
4179 | if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) { | |
4180 | u64 snap_id; | |
4181 | ||
4182 | snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name); | |
4183 | if (snap_id == CEPH_NOSNAP) | |
4184 | return -ENOENT; | |
4185 | spec->snap_id = snap_id; | |
4186 | } else { | |
4187 | spec->snap_id = CEPH_NOSNAP; | |
4188 | } | |
4189 | ||
4190 | return 0; | |
4191 | } | |
4192 | ||
4193 | /* Get the pool name; we have to make our own copy of this */ | |
4194 | ||
4195 | pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id); | |
4196 | if (!pool_name) { | |
4197 | rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id); | |
4198 | return -EIO; | |
4199 | } | |
4200 | pool_name = kstrdup(pool_name, GFP_KERNEL); | |
4201 | if (!pool_name) | |
4202 | return -ENOMEM; | |
4203 | ||
4204 | /* Fetch the image name; tolerate failure here */ | |
4205 | ||
4206 | image_name = rbd_dev_image_name(rbd_dev); | |
4207 | if (!image_name) | |
4208 | rbd_warn(rbd_dev, "unable to get image name"); | |
4209 | ||
4210 | /* Look up the snapshot name, and make a copy */ | |
4211 | ||
4212 | snap_name = rbd_snap_name(rbd_dev, spec->snap_id); | |
4213 | if (IS_ERR(snap_name)) { | |
4214 | ret = PTR_ERR(snap_name); | |
4215 | goto out_err; | |
4216 | } | |
4217 | ||
4218 | spec->pool_name = pool_name; | |
4219 | spec->image_name = image_name; | |
4220 | spec->snap_name = snap_name; | |
4221 | ||
4222 | return 0; | |
4223 | out_err: | |
4224 | kfree(image_name); | |
4225 | kfree(pool_name); | |
4226 | ||
4227 | return ret; | |
4228 | } | |
4229 | ||
4230 | static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev) | |
4231 | { | |
4232 | size_t size; | |
4233 | int ret; | |
4234 | void *reply_buf; | |
4235 | void *p; | |
4236 | void *end; | |
4237 | u64 seq; | |
4238 | u32 snap_count; | |
4239 | struct ceph_snap_context *snapc; | |
4240 | u32 i; | |
4241 | ||
4242 | /* | |
4243 | * We'll need room for the seq value (maximum snapshot id), | |
4244 | * snapshot count, and array of that many snapshot ids. | |
4245 | * For now we have a fixed upper limit on the number we're | |
4246 | * prepared to receive. | |
4247 | */ | |
4248 | size = sizeof (__le64) + sizeof (__le32) + | |
4249 | RBD_MAX_SNAP_COUNT * sizeof (__le64); | |
4250 | reply_buf = kzalloc(size, GFP_KERNEL); | |
4251 | if (!reply_buf) | |
4252 | return -ENOMEM; | |
4253 | ||
4254 | ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, | |
4255 | "rbd", "get_snapcontext", NULL, 0, | |
4256 | reply_buf, size); | |
4257 | dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); | |
4258 | if (ret < 0) | |
4259 | goto out; | |
4260 | ||
4261 | p = reply_buf; | |
4262 | end = reply_buf + ret; | |
4263 | ret = -ERANGE; | |
4264 | ceph_decode_64_safe(&p, end, seq, out); | |
4265 | ceph_decode_32_safe(&p, end, snap_count, out); | |
4266 | ||
4267 | /* | |
4268 | * Make sure the reported number of snapshot ids wouldn't go | |
4269 | * beyond the end of our buffer. But before checking that, | |
4270 | * make sure the computed size of the snapshot context we | |
4271 | * allocate is representable in a size_t. | |
4272 | */ | |
4273 | if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context)) | |
4274 | / sizeof (u64)) { | |
4275 | ret = -EINVAL; | |
4276 | goto out; | |
4277 | } | |
4278 | if (!ceph_has_room(&p, end, snap_count * sizeof (__le64))) | |
4279 | goto out; | |
4280 | ret = 0; | |
4281 | ||
4282 | snapc = ceph_create_snap_context(snap_count, GFP_KERNEL); | |
4283 | if (!snapc) { | |
4284 | ret = -ENOMEM; | |
4285 | goto out; | |
4286 | } | |
4287 | snapc->seq = seq; | |
4288 | for (i = 0; i < snap_count; i++) | |
4289 | snapc->snaps[i] = ceph_decode_64(&p); | |
4290 | ||
4291 | ceph_put_snap_context(rbd_dev->header.snapc); | |
4292 | rbd_dev->header.snapc = snapc; | |
4293 | ||
4294 | dout(" snap context seq = %llu, snap_count = %u\n", | |
4295 | (unsigned long long)seq, (unsigned int)snap_count); | |
4296 | out: | |
4297 | kfree(reply_buf); | |
4298 | ||
4299 | return ret; | |
4300 | } | |
4301 | ||
4302 | static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, | |
4303 | u64 snap_id) | |
4304 | { | |
4305 | size_t size; | |
4306 | void *reply_buf; | |
4307 | __le64 snapid; | |
4308 | int ret; | |
4309 | void *p; | |
4310 | void *end; | |
4311 | char *snap_name; | |
4312 | ||
4313 | size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN; | |
4314 | reply_buf = kmalloc(size, GFP_KERNEL); | |
4315 | if (!reply_buf) | |
4316 | return ERR_PTR(-ENOMEM); | |
4317 | ||
4318 | snapid = cpu_to_le64(snap_id); | |
4319 | ret = rbd_obj_method_sync(rbd_dev, rbd_dev->header_name, | |
4320 | "rbd", "get_snapshot_name", | |
4321 | &snapid, sizeof (snapid), | |
4322 | reply_buf, size); | |
4323 | dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); | |
4324 | if (ret < 0) { | |
4325 | snap_name = ERR_PTR(ret); | |
4326 | goto out; | |
4327 | } | |
4328 | ||
4329 | p = reply_buf; | |
4330 | end = reply_buf + ret; | |
4331 | snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL); | |
4332 | if (IS_ERR(snap_name)) | |
4333 | goto out; | |
4334 | ||
4335 | dout(" snap_id 0x%016llx snap_name = %s\n", | |
4336 | (unsigned long long)snap_id, snap_name); | |
4337 | out: | |
4338 | kfree(reply_buf); | |
4339 | ||
4340 | return snap_name; | |
4341 | } | |
4342 | ||
4343 | static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev) | |
4344 | { | |
4345 | bool first_time = rbd_dev->header.object_prefix == NULL; | |
4346 | int ret; | |
4347 | ||
4348 | ret = rbd_dev_v2_image_size(rbd_dev); | |
4349 | if (ret) | |
4350 | return ret; | |
4351 | ||
4352 | if (first_time) { | |
4353 | ret = rbd_dev_v2_header_onetime(rbd_dev); | |
4354 | if (ret) | |
4355 | return ret; | |
4356 | } | |
4357 | ||
4358 | /* | |
4359 | * If the image supports layering, get the parent info. We | |
4360 | * need to probe the first time regardless. Thereafter we | |
4361 | * only need to if there's a parent, to see if it has | |
4362 | * disappeared due to the mapped image getting flattened. | |
4363 | */ | |
4364 | if (rbd_dev->header.features & RBD_FEATURE_LAYERING && | |
4365 | (first_time || rbd_dev->parent_spec)) { | |
4366 | bool warn; | |
4367 | ||
4368 | ret = rbd_dev_v2_parent_info(rbd_dev); | |
4369 | if (ret) | |
4370 | return ret; | |
4371 | ||
4372 | /* | |
4373 | * Print a warning if this is the initial probe and | |
4374 | * the image has a parent. Don't print it if the | |
4375 | * image now being probed is itself a parent. We | |
4376 | * can tell at this point because we won't know its | |
4377 | * pool name yet (just its pool id). | |
4378 | */ | |
4379 | warn = rbd_dev->parent_spec && rbd_dev->spec->pool_name; | |
4380 | if (first_time && warn) | |
4381 | rbd_warn(rbd_dev, "WARNING: kernel layering " | |
4382 | "is EXPERIMENTAL!"); | |
4383 | } | |
4384 | ||
4385 | if (rbd_dev->spec->snap_id == CEPH_NOSNAP) | |
4386 | if (rbd_dev->mapping.size != rbd_dev->header.image_size) | |
4387 | rbd_dev->mapping.size = rbd_dev->header.image_size; | |
4388 | ||
4389 | ret = rbd_dev_v2_snap_context(rbd_dev); | |
4390 | dout("rbd_dev_v2_snap_context returned %d\n", ret); | |
4391 | ||
4392 | return ret; | |
4393 | } | |
4394 | ||
4395 | static int rbd_bus_add_dev(struct rbd_device *rbd_dev) | |
4396 | { | |
4397 | struct device *dev; | |
4398 | int ret; | |
4399 | ||
4400 | dev = &rbd_dev->dev; | |
4401 | dev->bus = &rbd_bus_type; | |
4402 | dev->type = &rbd_device_type; | |
4403 | dev->parent = &rbd_root_dev; | |
4404 | dev->release = rbd_dev_device_release; | |
4405 | dev_set_name(dev, "%d", rbd_dev->dev_id); | |
4406 | ret = device_register(dev); | |
4407 | ||
4408 | return ret; | |
4409 | } | |
4410 | ||
4411 | static void rbd_bus_del_dev(struct rbd_device *rbd_dev) | |
4412 | { | |
4413 | device_unregister(&rbd_dev->dev); | |
4414 | } | |
4415 | ||
4416 | /* | |
4417 | * Get a unique rbd identifier for the given new rbd_dev, and add | |
4418 | * the rbd_dev to the global list. | |
4419 | */ | |
4420 | static int rbd_dev_id_get(struct rbd_device *rbd_dev) | |
4421 | { | |
4422 | int new_dev_id; | |
4423 | ||
4424 | new_dev_id = ida_simple_get(&rbd_dev_id_ida, | |
4425 | 0, minor_to_rbd_dev_id(1 << MINORBITS), | |
4426 | GFP_KERNEL); | |
4427 | if (new_dev_id < 0) | |
4428 | return new_dev_id; | |
4429 | ||
4430 | rbd_dev->dev_id = new_dev_id; | |
4431 | ||
4432 | spin_lock(&rbd_dev_list_lock); | |
4433 | list_add_tail(&rbd_dev->node, &rbd_dev_list); | |
4434 | spin_unlock(&rbd_dev_list_lock); | |
4435 | ||
4436 | dout("rbd_dev %p given dev id %d\n", rbd_dev, rbd_dev->dev_id); | |
4437 | ||
4438 | return 0; | |
4439 | } | |
4440 | ||
4441 | /* | |
4442 | * Remove an rbd_dev from the global list, and record that its | |
4443 | * identifier is no longer in use. | |
4444 | */ | |
4445 | static void rbd_dev_id_put(struct rbd_device *rbd_dev) | |
4446 | { | |
4447 | spin_lock(&rbd_dev_list_lock); | |
4448 | list_del_init(&rbd_dev->node); | |
4449 | spin_unlock(&rbd_dev_list_lock); | |
4450 | ||
4451 | ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id); | |
4452 | ||
4453 | dout("rbd_dev %p released dev id %d\n", rbd_dev, rbd_dev->dev_id); | |
4454 | } | |
4455 | ||
4456 | /* | |
4457 | * Skips over white space at *buf, and updates *buf to point to the | |
4458 | * first found non-space character (if any). Returns the length of | |
4459 | * the token (string of non-white space characters) found. Note | |
4460 | * that *buf must be terminated with '\0'. | |
4461 | */ | |
4462 | static inline size_t next_token(const char **buf) | |
4463 | { | |
4464 | /* | |
4465 | * These are the characters that produce nonzero for | |
4466 | * isspace() in the "C" and "POSIX" locales. | |
4467 | */ | |
4468 | const char *spaces = " \f\n\r\t\v"; | |
4469 | ||
4470 | *buf += strspn(*buf, spaces); /* Find start of token */ | |
4471 | ||
4472 | return strcspn(*buf, spaces); /* Return token length */ | |
4473 | } | |
4474 | ||
4475 | /* | |
4476 | * Finds the next token in *buf, and if the provided token buffer is | |
4477 | * big enough, copies the found token into it. The result, if | |
4478 | * copied, is guaranteed to be terminated with '\0'. Note that *buf | |
4479 | * must be terminated with '\0' on entry. | |
4480 | * | |
4481 | * Returns the length of the token found (not including the '\0'). | |
4482 | * Return value will be 0 if no token is found, and it will be >= | |
4483 | * token_size if the token would not fit. | |
4484 | * | |
4485 | * The *buf pointer will be updated to point beyond the end of the | |
4486 | * found token. Note that this occurs even if the token buffer is | |
4487 | * too small to hold it. | |
4488 | */ | |
4489 | static inline size_t copy_token(const char **buf, | |
4490 | char *token, | |
4491 | size_t token_size) | |
4492 | { | |
4493 | size_t len; | |
4494 | ||
4495 | len = next_token(buf); | |
4496 | if (len < token_size) { | |
4497 | memcpy(token, *buf, len); | |
4498 | *(token + len) = '\0'; | |
4499 | } | |
4500 | *buf += len; | |
4501 | ||
4502 | return len; | |
4503 | } | |
4504 | ||
4505 | /* | |
4506 | * Finds the next token in *buf, dynamically allocates a buffer big | |
4507 | * enough to hold a copy of it, and copies the token into the new | |
4508 | * buffer. The copy is guaranteed to be terminated with '\0'. Note | |
4509 | * that a duplicate buffer is created even for a zero-length token. | |
4510 | * | |
4511 | * Returns a pointer to the newly-allocated duplicate, or a null | |
4512 | * pointer if memory for the duplicate was not available. If | |
4513 | * the lenp argument is a non-null pointer, the length of the token | |
4514 | * (not including the '\0') is returned in *lenp. | |
4515 | * | |
4516 | * If successful, the *buf pointer will be updated to point beyond | |
4517 | * the end of the found token. | |
4518 | * | |
4519 | * Note: uses GFP_KERNEL for allocation. | |
4520 | */ | |
4521 | static inline char *dup_token(const char **buf, size_t *lenp) | |
4522 | { | |
4523 | char *dup; | |
4524 | size_t len; | |
4525 | ||
4526 | len = next_token(buf); | |
4527 | dup = kmemdup(*buf, len + 1, GFP_KERNEL); | |
4528 | if (!dup) | |
4529 | return NULL; | |
4530 | *(dup + len) = '\0'; | |
4531 | *buf += len; | |
4532 | ||
4533 | if (lenp) | |
4534 | *lenp = len; | |
4535 | ||
4536 | return dup; | |
4537 | } | |
4538 | ||
4539 | /* | |
4540 | * Parse the options provided for an "rbd add" (i.e., rbd image | |
4541 | * mapping) request. These arrive via a write to /sys/bus/rbd/add, | |
4542 | * and the data written is passed here via a NUL-terminated buffer. | |
4543 | * Returns 0 if successful or an error code otherwise. | |
4544 | * | |
4545 | * The information extracted from these options is recorded in | |
4546 | * the other parameters which return dynamically-allocated | |
4547 | * structures: | |
4548 | * ceph_opts | |
4549 | * The address of a pointer that will refer to a ceph options | |
4550 | * structure. Caller must release the returned pointer using | |
4551 | * ceph_destroy_options() when it is no longer needed. | |
4552 | * rbd_opts | |
4553 | * Address of an rbd options pointer. Fully initialized by | |
4554 | * this function; caller must release with kfree(). | |
4555 | * spec | |
4556 | * Address of an rbd image specification pointer. Fully | |
4557 | * initialized by this function based on parsed options. | |
4558 | * Caller must release with rbd_spec_put(). | |
4559 | * | |
4560 | * The options passed take this form: | |
4561 | * <mon_addrs> <options> <pool_name> <image_name> [<snap_id>] | |
4562 | * where: | |
4563 | * <mon_addrs> | |
4564 | * A comma-separated list of one or more monitor addresses. | |
4565 | * A monitor address is an ip address, optionally followed | |
4566 | * by a port number (separated by a colon). | |
4567 | * I.e.: ip1[:port1][,ip2[:port2]...] | |
4568 | * <options> | |
4569 | * A comma-separated list of ceph and/or rbd options. | |
4570 | * <pool_name> | |
4571 | * The name of the rados pool containing the rbd image. | |
4572 | * <image_name> | |
4573 | * The name of the image in that pool to map. | |
4574 | * <snap_id> | |
4575 | * An optional snapshot id. If provided, the mapping will | |
4576 | * present data from the image at the time that snapshot was | |
4577 | * created. The image head is used if no snapshot id is | |
4578 | * provided. Snapshot mappings are always read-only. | |
4579 | */ | |
4580 | static int rbd_add_parse_args(const char *buf, | |
4581 | struct ceph_options **ceph_opts, | |
4582 | struct rbd_options **opts, | |
4583 | struct rbd_spec **rbd_spec) | |
4584 | { | |
4585 | size_t len; | |
4586 | char *options; | |
4587 | const char *mon_addrs; | |
4588 | char *snap_name; | |
4589 | size_t mon_addrs_size; | |
4590 | struct rbd_spec *spec = NULL; | |
4591 | struct rbd_options *rbd_opts = NULL; | |
4592 | struct ceph_options *copts; | |
4593 | int ret; | |
4594 | ||
4595 | /* The first four tokens are required */ | |
4596 | ||
4597 | len = next_token(&buf); | |
4598 | if (!len) { | |
4599 | rbd_warn(NULL, "no monitor address(es) provided"); | |
4600 | return -EINVAL; | |
4601 | } | |
4602 | mon_addrs = buf; | |
4603 | mon_addrs_size = len + 1; | |
4604 | buf += len; | |
4605 | ||
4606 | ret = -EINVAL; | |
4607 | options = dup_token(&buf, NULL); | |
4608 | if (!options) | |
4609 | return -ENOMEM; | |
4610 | if (!*options) { | |
4611 | rbd_warn(NULL, "no options provided"); | |
4612 | goto out_err; | |
4613 | } | |
4614 | ||
4615 | spec = rbd_spec_alloc(); | |
4616 | if (!spec) | |
4617 | goto out_mem; | |
4618 | ||
4619 | spec->pool_name = dup_token(&buf, NULL); | |
4620 | if (!spec->pool_name) | |
4621 | goto out_mem; | |
4622 | if (!*spec->pool_name) { | |
4623 | rbd_warn(NULL, "no pool name provided"); | |
4624 | goto out_err; | |
4625 | } | |
4626 | ||
4627 | spec->image_name = dup_token(&buf, NULL); | |
4628 | if (!spec->image_name) | |
4629 | goto out_mem; | |
4630 | if (!*spec->image_name) { | |
4631 | rbd_warn(NULL, "no image name provided"); | |
4632 | goto out_err; | |
4633 | } | |
4634 | ||
4635 | /* | |
4636 | * Snapshot name is optional; default is to use "-" | |
4637 | * (indicating the head/no snapshot). | |
4638 | */ | |
4639 | len = next_token(&buf); | |
4640 | if (!len) { | |
4641 | buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */ | |
4642 | len = sizeof (RBD_SNAP_HEAD_NAME) - 1; | |
4643 | } else if (len > RBD_MAX_SNAP_NAME_LEN) { | |
4644 | ret = -ENAMETOOLONG; | |
4645 | goto out_err; | |
4646 | } | |
4647 | snap_name = kmemdup(buf, len + 1, GFP_KERNEL); | |
4648 | if (!snap_name) | |
4649 | goto out_mem; | |
4650 | *(snap_name + len) = '\0'; | |
4651 | spec->snap_name = snap_name; | |
4652 | ||
4653 | /* Initialize all rbd options to the defaults */ | |
4654 | ||
4655 | rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL); | |
4656 | if (!rbd_opts) | |
4657 | goto out_mem; | |
4658 | ||
4659 | rbd_opts->read_only = RBD_READ_ONLY_DEFAULT; | |
4660 | ||
4661 | copts = ceph_parse_options(options, mon_addrs, | |
4662 | mon_addrs + mon_addrs_size - 1, | |
4663 | parse_rbd_opts_token, rbd_opts); | |
4664 | if (IS_ERR(copts)) { | |
4665 | ret = PTR_ERR(copts); | |
4666 | goto out_err; | |
4667 | } | |
4668 | kfree(options); | |
4669 | ||
4670 | *ceph_opts = copts; | |
4671 | *opts = rbd_opts; | |
4672 | *rbd_spec = spec; | |
4673 | ||
4674 | return 0; | |
4675 | out_mem: | |
4676 | ret = -ENOMEM; | |
4677 | out_err: | |
4678 | kfree(rbd_opts); | |
4679 | rbd_spec_put(spec); | |
4680 | kfree(options); | |
4681 | ||
4682 | return ret; | |
4683 | } | |
4684 | ||
4685 | /* | |
4686 | * Return pool id (>= 0) or a negative error code. | |
4687 | */ | |
4688 | static int rbd_add_get_pool_id(struct rbd_client *rbdc, const char *pool_name) | |
4689 | { | |
4690 | u64 newest_epoch; | |
4691 | unsigned long timeout = rbdc->client->options->mount_timeout * HZ; | |
4692 | int tries = 0; | |
4693 | int ret; | |
4694 | ||
4695 | again: | |
4696 | ret = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, pool_name); | |
4697 | if (ret == -ENOENT && tries++ < 1) { | |
4698 | ret = ceph_monc_do_get_version(&rbdc->client->monc, "osdmap", | |
4699 | &newest_epoch); | |
4700 | if (ret < 0) | |
4701 | return ret; | |
4702 | ||
4703 | if (rbdc->client->osdc.osdmap->epoch < newest_epoch) { | |
4704 | ceph_monc_request_next_osdmap(&rbdc->client->monc); | |
4705 | (void) ceph_monc_wait_osdmap(&rbdc->client->monc, | |
4706 | newest_epoch, timeout); | |
4707 | goto again; | |
4708 | } else { | |
4709 | /* the osdmap we have is new enough */ | |
4710 | return -ENOENT; | |
4711 | } | |
4712 | } | |
4713 | ||
4714 | return ret; | |
4715 | } | |
4716 | ||
4717 | /* | |
4718 | * An rbd format 2 image has a unique identifier, distinct from the | |
4719 | * name given to it by the user. Internally, that identifier is | |
4720 | * what's used to specify the names of objects related to the image. | |
4721 | * | |
4722 | * A special "rbd id" object is used to map an rbd image name to its | |
4723 | * id. If that object doesn't exist, then there is no v2 rbd image | |
4724 | * with the supplied name. | |
4725 | * | |
4726 | * This function will record the given rbd_dev's image_id field if | |
4727 | * it can be determined, and in that case will return 0. If any | |
4728 | * errors occur a negative errno will be returned and the rbd_dev's | |
4729 | * image_id field will be unchanged (and should be NULL). | |
4730 | */ | |
4731 | static int rbd_dev_image_id(struct rbd_device *rbd_dev) | |
4732 | { | |
4733 | int ret; | |
4734 | size_t size; | |
4735 | char *object_name; | |
4736 | void *response; | |
4737 | char *image_id; | |
4738 | ||
4739 | /* | |
4740 | * When probing a parent image, the image id is already | |
4741 | * known (and the image name likely is not). There's no | |
4742 | * need to fetch the image id again in this case. We | |
4743 | * do still need to set the image format though. | |
4744 | */ | |
4745 | if (rbd_dev->spec->image_id) { | |
4746 | rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1; | |
4747 | ||
4748 | return 0; | |
4749 | } | |
4750 | ||
4751 | /* | |
4752 | * First, see if the format 2 image id file exists, and if | |
4753 | * so, get the image's persistent id from it. | |
4754 | */ | |
4755 | size = sizeof (RBD_ID_PREFIX) + strlen(rbd_dev->spec->image_name); | |
4756 | object_name = kmalloc(size, GFP_NOIO); | |
4757 | if (!object_name) | |
4758 | return -ENOMEM; | |
4759 | sprintf(object_name, "%s%s", RBD_ID_PREFIX, rbd_dev->spec->image_name); | |
4760 | dout("rbd id object name is %s\n", object_name); | |
4761 | ||
4762 | /* Response will be an encoded string, which includes a length */ | |
4763 | ||
4764 | size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX; | |
4765 | response = kzalloc(size, GFP_NOIO); | |
4766 | if (!response) { | |
4767 | ret = -ENOMEM; | |
4768 | goto out; | |
4769 | } | |
4770 | ||
4771 | /* If it doesn't exist we'll assume it's a format 1 image */ | |
4772 | ||
4773 | ret = rbd_obj_method_sync(rbd_dev, object_name, | |
4774 | "rbd", "get_id", NULL, 0, | |
4775 | response, RBD_IMAGE_ID_LEN_MAX); | |
4776 | dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret); | |
4777 | if (ret == -ENOENT) { | |
4778 | image_id = kstrdup("", GFP_KERNEL); | |
4779 | ret = image_id ? 0 : -ENOMEM; | |
4780 | if (!ret) | |
4781 | rbd_dev->image_format = 1; | |
4782 | } else if (ret > sizeof (__le32)) { | |
4783 | void *p = response; | |
4784 | ||
4785 | image_id = ceph_extract_encoded_string(&p, p + ret, | |
4786 | NULL, GFP_NOIO); | |
4787 | ret = PTR_ERR_OR_ZERO(image_id); | |
4788 | if (!ret) | |
4789 | rbd_dev->image_format = 2; | |
4790 | } else { | |
4791 | ret = -EINVAL; | |
4792 | } | |
4793 | ||
4794 | if (!ret) { | |
4795 | rbd_dev->spec->image_id = image_id; | |
4796 | dout("image_id is %s\n", image_id); | |
4797 | } | |
4798 | out: | |
4799 | kfree(response); | |
4800 | kfree(object_name); | |
4801 | ||
4802 | return ret; | |
4803 | } | |
4804 | ||
4805 | /* | |
4806 | * Undo whatever state changes are made by v1 or v2 header info | |
4807 | * call. | |
4808 | */ | |
4809 | static void rbd_dev_unprobe(struct rbd_device *rbd_dev) | |
4810 | { | |
4811 | struct rbd_image_header *header; | |
4812 | ||
4813 | /* Drop parent reference unless it's already been done (or none) */ | |
4814 | ||
4815 | if (rbd_dev->parent_overlap) | |
4816 | rbd_dev_parent_put(rbd_dev); | |
4817 | ||
4818 | /* Free dynamic fields from the header, then zero it out */ | |
4819 | ||
4820 | header = &rbd_dev->header; | |
4821 | ceph_put_snap_context(header->snapc); | |
4822 | kfree(header->snap_sizes); | |
4823 | kfree(header->snap_names); | |
4824 | kfree(header->object_prefix); | |
4825 | memset(header, 0, sizeof (*header)); | |
4826 | } | |
4827 | ||
4828 | static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev) | |
4829 | { | |
4830 | int ret; | |
4831 | ||
4832 | ret = rbd_dev_v2_object_prefix(rbd_dev); | |
4833 | if (ret) | |
4834 | goto out_err; | |
4835 | ||
4836 | /* | |
4837 | * Get the and check features for the image. Currently the | |
4838 | * features are assumed to never change. | |
4839 | */ | |
4840 | ret = rbd_dev_v2_features(rbd_dev); | |
4841 | if (ret) | |
4842 | goto out_err; | |
4843 | ||
4844 | /* If the image supports fancy striping, get its parameters */ | |
4845 | ||
4846 | if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) { | |
4847 | ret = rbd_dev_v2_striping_info(rbd_dev); | |
4848 | if (ret < 0) | |
4849 | goto out_err; | |
4850 | } | |
4851 | /* No support for crypto and compression type format 2 images */ | |
4852 | ||
4853 | return 0; | |
4854 | out_err: | |
4855 | rbd_dev->header.features = 0; | |
4856 | kfree(rbd_dev->header.object_prefix); | |
4857 | rbd_dev->header.object_prefix = NULL; | |
4858 | ||
4859 | return ret; | |
4860 | } | |
4861 | ||
4862 | static int rbd_dev_probe_parent(struct rbd_device *rbd_dev) | |
4863 | { | |
4864 | struct rbd_device *parent = NULL; | |
4865 | struct rbd_spec *parent_spec; | |
4866 | struct rbd_client *rbdc; | |
4867 | int ret; | |
4868 | ||
4869 | if (!rbd_dev->parent_spec) | |
4870 | return 0; | |
4871 | /* | |
4872 | * We need to pass a reference to the client and the parent | |
4873 | * spec when creating the parent rbd_dev. Images related by | |
4874 | * parent/child relationships always share both. | |
4875 | */ | |
4876 | parent_spec = rbd_spec_get(rbd_dev->parent_spec); | |
4877 | rbdc = __rbd_get_client(rbd_dev->rbd_client); | |
4878 | ||
4879 | ret = -ENOMEM; | |
4880 | parent = rbd_dev_create(rbdc, parent_spec); | |
4881 | if (!parent) | |
4882 | goto out_err; | |
4883 | ||
4884 | ret = rbd_dev_image_probe(parent, false); | |
4885 | if (ret < 0) | |
4886 | goto out_err; | |
4887 | rbd_dev->parent = parent; | |
4888 | atomic_set(&rbd_dev->parent_ref, 1); | |
4889 | ||
4890 | return 0; | |
4891 | out_err: | |
4892 | if (parent) { | |
4893 | rbd_dev_unparent(rbd_dev); | |
4894 | kfree(rbd_dev->header_name); | |
4895 | rbd_dev_destroy(parent); | |
4896 | } else { | |
4897 | rbd_put_client(rbdc); | |
4898 | rbd_spec_put(parent_spec); | |
4899 | } | |
4900 | ||
4901 | return ret; | |
4902 | } | |
4903 | ||
4904 | static int rbd_dev_device_setup(struct rbd_device *rbd_dev) | |
4905 | { | |
4906 | int ret; | |
4907 | ||
4908 | /* Get an id and fill in device name. */ | |
4909 | ||
4910 | ret = rbd_dev_id_get(rbd_dev); | |
4911 | if (ret) | |
4912 | return ret; | |
4913 | ||
4914 | BUILD_BUG_ON(DEV_NAME_LEN | |
4915 | < sizeof (RBD_DRV_NAME) + MAX_INT_FORMAT_WIDTH); | |
4916 | sprintf(rbd_dev->name, "%s%d", RBD_DRV_NAME, rbd_dev->dev_id); | |
4917 | ||
4918 | /* Record our major and minor device numbers. */ | |
4919 | ||
4920 | if (!single_major) { | |
4921 | ret = register_blkdev(0, rbd_dev->name); | |
4922 | if (ret < 0) | |
4923 | goto err_out_id; | |
4924 | ||
4925 | rbd_dev->major = ret; | |
4926 | rbd_dev->minor = 0; | |
4927 | } else { | |
4928 | rbd_dev->major = rbd_major; | |
4929 | rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id); | |
4930 | } | |
4931 | ||
4932 | /* Set up the blkdev mapping. */ | |
4933 | ||
4934 | ret = rbd_init_disk(rbd_dev); | |
4935 | if (ret) | |
4936 | goto err_out_blkdev; | |
4937 | ||
4938 | ret = rbd_dev_mapping_set(rbd_dev); | |
4939 | if (ret) | |
4940 | goto err_out_disk; | |
4941 | set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE); | |
4942 | ||
4943 | ret = rbd_bus_add_dev(rbd_dev); | |
4944 | if (ret) | |
4945 | goto err_out_mapping; | |
4946 | ||
4947 | /* Everything's ready. Announce the disk to the world. */ | |
4948 | ||
4949 | set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); | |
4950 | add_disk(rbd_dev->disk); | |
4951 | ||
4952 | pr_info("%s: added with size 0x%llx\n", rbd_dev->disk->disk_name, | |
4953 | (unsigned long long) rbd_dev->mapping.size); | |
4954 | ||
4955 | return ret; | |
4956 | ||
4957 | err_out_mapping: | |
4958 | rbd_dev_mapping_clear(rbd_dev); | |
4959 | err_out_disk: | |
4960 | rbd_free_disk(rbd_dev); | |
4961 | err_out_blkdev: | |
4962 | if (!single_major) | |
4963 | unregister_blkdev(rbd_dev->major, rbd_dev->name); | |
4964 | err_out_id: | |
4965 | rbd_dev_id_put(rbd_dev); | |
4966 | rbd_dev_mapping_clear(rbd_dev); | |
4967 | ||
4968 | return ret; | |
4969 | } | |
4970 | ||
4971 | static int rbd_dev_header_name(struct rbd_device *rbd_dev) | |
4972 | { | |
4973 | struct rbd_spec *spec = rbd_dev->spec; | |
4974 | size_t size; | |
4975 | ||
4976 | /* Record the header object name for this rbd image. */ | |
4977 | ||
4978 | rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); | |
4979 | ||
4980 | if (rbd_dev->image_format == 1) | |
4981 | size = strlen(spec->image_name) + sizeof (RBD_SUFFIX); | |
4982 | else | |
4983 | size = sizeof (RBD_HEADER_PREFIX) + strlen(spec->image_id); | |
4984 | ||
4985 | rbd_dev->header_name = kmalloc(size, GFP_KERNEL); | |
4986 | if (!rbd_dev->header_name) | |
4987 | return -ENOMEM; | |
4988 | ||
4989 | if (rbd_dev->image_format == 1) | |
4990 | sprintf(rbd_dev->header_name, "%s%s", | |
4991 | spec->image_name, RBD_SUFFIX); | |
4992 | else | |
4993 | sprintf(rbd_dev->header_name, "%s%s", | |
4994 | RBD_HEADER_PREFIX, spec->image_id); | |
4995 | return 0; | |
4996 | } | |
4997 | ||
4998 | static void rbd_dev_image_release(struct rbd_device *rbd_dev) | |
4999 | { | |
5000 | rbd_dev_unprobe(rbd_dev); | |
5001 | kfree(rbd_dev->header_name); | |
5002 | rbd_dev->header_name = NULL; | |
5003 | rbd_dev->image_format = 0; | |
5004 | kfree(rbd_dev->spec->image_id); | |
5005 | rbd_dev->spec->image_id = NULL; | |
5006 | ||
5007 | rbd_dev_destroy(rbd_dev); | |
5008 | } | |
5009 | ||
5010 | /* | |
5011 | * Probe for the existence of the header object for the given rbd | |
5012 | * device. If this image is the one being mapped (i.e., not a | |
5013 | * parent), initiate a watch on its header object before using that | |
5014 | * object to get detailed information about the rbd image. | |
5015 | */ | |
5016 | static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool mapping) | |
5017 | { | |
5018 | int ret; | |
5019 | ||
5020 | /* | |
5021 | * Get the id from the image id object. Unless there's an | |
5022 | * error, rbd_dev->spec->image_id will be filled in with | |
5023 | * a dynamically-allocated string, and rbd_dev->image_format | |
5024 | * will be set to either 1 or 2. | |
5025 | */ | |
5026 | ret = rbd_dev_image_id(rbd_dev); | |
5027 | if (ret) | |
5028 | return ret; | |
5029 | rbd_assert(rbd_dev->spec->image_id); | |
5030 | rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); | |
5031 | ||
5032 | ret = rbd_dev_header_name(rbd_dev); | |
5033 | if (ret) | |
5034 | goto err_out_format; | |
5035 | ||
5036 | if (mapping) { | |
5037 | ret = rbd_dev_header_watch_sync(rbd_dev); | |
5038 | if (ret) | |
5039 | goto out_header_name; | |
5040 | } | |
5041 | ||
5042 | if (rbd_dev->image_format == 1) | |
5043 | ret = rbd_dev_v1_header_info(rbd_dev); | |
5044 | else | |
5045 | ret = rbd_dev_v2_header_info(rbd_dev); | |
5046 | if (ret) | |
5047 | goto err_out_watch; | |
5048 | ||
5049 | ret = rbd_dev_spec_update(rbd_dev); | |
5050 | if (ret) | |
5051 | goto err_out_probe; | |
5052 | ||
5053 | ret = rbd_dev_probe_parent(rbd_dev); | |
5054 | if (ret) | |
5055 | goto err_out_probe; | |
5056 | ||
5057 | dout("discovered format %u image, header name is %s\n", | |
5058 | rbd_dev->image_format, rbd_dev->header_name); | |
5059 | ||
5060 | return 0; | |
5061 | err_out_probe: | |
5062 | rbd_dev_unprobe(rbd_dev); | |
5063 | err_out_watch: | |
5064 | if (mapping) | |
5065 | rbd_dev_header_unwatch_sync(rbd_dev); | |
5066 | out_header_name: | |
5067 | kfree(rbd_dev->header_name); | |
5068 | rbd_dev->header_name = NULL; | |
5069 | err_out_format: | |
5070 | rbd_dev->image_format = 0; | |
5071 | kfree(rbd_dev->spec->image_id); | |
5072 | rbd_dev->spec->image_id = NULL; | |
5073 | ||
5074 | dout("probe failed, returning %d\n", ret); | |
5075 | ||
5076 | return ret; | |
5077 | } | |
5078 | ||
5079 | static ssize_t do_rbd_add(struct bus_type *bus, | |
5080 | const char *buf, | |
5081 | size_t count) | |
5082 | { | |
5083 | struct rbd_device *rbd_dev = NULL; | |
5084 | struct ceph_options *ceph_opts = NULL; | |
5085 | struct rbd_options *rbd_opts = NULL; | |
5086 | struct rbd_spec *spec = NULL; | |
5087 | struct rbd_client *rbdc; | |
5088 | bool read_only; | |
5089 | int rc = -ENOMEM; | |
5090 | ||
5091 | if (!try_module_get(THIS_MODULE)) | |
5092 | return -ENODEV; | |
5093 | ||
5094 | /* parse add command */ | |
5095 | rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec); | |
5096 | if (rc < 0) | |
5097 | goto err_out_module; | |
5098 | read_only = rbd_opts->read_only; | |
5099 | kfree(rbd_opts); | |
5100 | rbd_opts = NULL; /* done with this */ | |
5101 | ||
5102 | rbdc = rbd_get_client(ceph_opts); | |
5103 | if (IS_ERR(rbdc)) { | |
5104 | rc = PTR_ERR(rbdc); | |
5105 | goto err_out_args; | |
5106 | } | |
5107 | ||
5108 | /* pick the pool */ | |
5109 | rc = rbd_add_get_pool_id(rbdc, spec->pool_name); | |
5110 | if (rc < 0) | |
5111 | goto err_out_client; | |
5112 | spec->pool_id = (u64)rc; | |
5113 | ||
5114 | /* The ceph file layout needs to fit pool id in 32 bits */ | |
5115 | ||
5116 | if (spec->pool_id > (u64)U32_MAX) { | |
5117 | rbd_warn(NULL, "pool id too large (%llu > %u)\n", | |
5118 | (unsigned long long)spec->pool_id, U32_MAX); | |
5119 | rc = -EIO; | |
5120 | goto err_out_client; | |
5121 | } | |
5122 | ||
5123 | rbd_dev = rbd_dev_create(rbdc, spec); | |
5124 | if (!rbd_dev) | |
5125 | goto err_out_client; | |
5126 | rbdc = NULL; /* rbd_dev now owns this */ | |
5127 | spec = NULL; /* rbd_dev now owns this */ | |
5128 | ||
5129 | rc = rbd_dev_image_probe(rbd_dev, true); | |
5130 | if (rc < 0) | |
5131 | goto err_out_rbd_dev; | |
5132 | ||
5133 | /* If we are mapping a snapshot it must be marked read-only */ | |
5134 | ||
5135 | if (rbd_dev->spec->snap_id != CEPH_NOSNAP) | |
5136 | read_only = true; | |
5137 | rbd_dev->mapping.read_only = read_only; | |
5138 | ||
5139 | rc = rbd_dev_device_setup(rbd_dev); | |
5140 | if (rc) { | |
5141 | /* | |
5142 | * rbd_dev_header_unwatch_sync() can't be moved into | |
5143 | * rbd_dev_image_release() without refactoring, see | |
5144 | * commit 1f3ef78861ac. | |
5145 | */ | |
5146 | rbd_dev_header_unwatch_sync(rbd_dev); | |
5147 | rbd_dev_image_release(rbd_dev); | |
5148 | goto err_out_module; | |
5149 | } | |
5150 | ||
5151 | return count; | |
5152 | ||
5153 | err_out_rbd_dev: | |
5154 | rbd_dev_destroy(rbd_dev); | |
5155 | err_out_client: | |
5156 | rbd_put_client(rbdc); | |
5157 | err_out_args: | |
5158 | rbd_spec_put(spec); | |
5159 | err_out_module: | |
5160 | module_put(THIS_MODULE); | |
5161 | ||
5162 | dout("Error adding device %s\n", buf); | |
5163 | ||
5164 | return (ssize_t)rc; | |
5165 | } | |
5166 | ||
5167 | static ssize_t rbd_add(struct bus_type *bus, | |
5168 | const char *buf, | |
5169 | size_t count) | |
5170 | { | |
5171 | if (single_major) | |
5172 | return -EINVAL; | |
5173 | ||
5174 | return do_rbd_add(bus, buf, count); | |
5175 | } | |
5176 | ||
5177 | static ssize_t rbd_add_single_major(struct bus_type *bus, | |
5178 | const char *buf, | |
5179 | size_t count) | |
5180 | { | |
5181 | return do_rbd_add(bus, buf, count); | |
5182 | } | |
5183 | ||
5184 | static void rbd_dev_device_release(struct device *dev) | |
5185 | { | |
5186 | struct rbd_device *rbd_dev = dev_to_rbd_dev(dev); | |
5187 | ||
5188 | rbd_free_disk(rbd_dev); | |
5189 | clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags); | |
5190 | rbd_dev_mapping_clear(rbd_dev); | |
5191 | if (!single_major) | |
5192 | unregister_blkdev(rbd_dev->major, rbd_dev->name); | |
5193 | rbd_dev_id_put(rbd_dev); | |
5194 | rbd_dev_mapping_clear(rbd_dev); | |
5195 | } | |
5196 | ||
5197 | static void rbd_dev_remove_parent(struct rbd_device *rbd_dev) | |
5198 | { | |
5199 | while (rbd_dev->parent) { | |
5200 | struct rbd_device *first = rbd_dev; | |
5201 | struct rbd_device *second = first->parent; | |
5202 | struct rbd_device *third; | |
5203 | ||
5204 | /* | |
5205 | * Follow to the parent with no grandparent and | |
5206 | * remove it. | |
5207 | */ | |
5208 | while (second && (third = second->parent)) { | |
5209 | first = second; | |
5210 | second = third; | |
5211 | } | |
5212 | rbd_assert(second); | |
5213 | rbd_dev_image_release(second); | |
5214 | first->parent = NULL; | |
5215 | first->parent_overlap = 0; | |
5216 | ||
5217 | rbd_assert(first->parent_spec); | |
5218 | rbd_spec_put(first->parent_spec); | |
5219 | first->parent_spec = NULL; | |
5220 | } | |
5221 | } | |
5222 | ||
5223 | static ssize_t do_rbd_remove(struct bus_type *bus, | |
5224 | const char *buf, | |
5225 | size_t count) | |
5226 | { | |
5227 | struct rbd_device *rbd_dev = NULL; | |
5228 | struct list_head *tmp; | |
5229 | int dev_id; | |
5230 | unsigned long ul; | |
5231 | bool already = false; | |
5232 | int ret; | |
5233 | ||
5234 | ret = kstrtoul(buf, 10, &ul); | |
5235 | if (ret) | |
5236 | return ret; | |
5237 | ||
5238 | /* convert to int; abort if we lost anything in the conversion */ | |
5239 | dev_id = (int)ul; | |
5240 | if (dev_id != ul) | |
5241 | return -EINVAL; | |
5242 | ||
5243 | ret = -ENOENT; | |
5244 | spin_lock(&rbd_dev_list_lock); | |
5245 | list_for_each(tmp, &rbd_dev_list) { | |
5246 | rbd_dev = list_entry(tmp, struct rbd_device, node); | |
5247 | if (rbd_dev->dev_id == dev_id) { | |
5248 | ret = 0; | |
5249 | break; | |
5250 | } | |
5251 | } | |
5252 | if (!ret) { | |
5253 | spin_lock_irq(&rbd_dev->lock); | |
5254 | if (rbd_dev->open_count) | |
5255 | ret = -EBUSY; | |
5256 | else | |
5257 | already = test_and_set_bit(RBD_DEV_FLAG_REMOVING, | |
5258 | &rbd_dev->flags); | |
5259 | spin_unlock_irq(&rbd_dev->lock); | |
5260 | } | |
5261 | spin_unlock(&rbd_dev_list_lock); | |
5262 | if (ret < 0 || already) | |
5263 | return ret; | |
5264 | ||
5265 | rbd_dev_header_unwatch_sync(rbd_dev); | |
5266 | /* | |
5267 | * flush remaining watch callbacks - these must be complete | |
5268 | * before the osd_client is shutdown | |
5269 | */ | |
5270 | dout("%s: flushing notifies", __func__); | |
5271 | ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc); | |
5272 | ||
5273 | /* | |
5274 | * Don't free anything from rbd_dev->disk until after all | |
5275 | * notifies are completely processed. Otherwise | |
5276 | * rbd_bus_del_dev() will race with rbd_watch_cb(), resulting | |
5277 | * in a potential use after free of rbd_dev->disk or rbd_dev. | |
5278 | */ | |
5279 | rbd_bus_del_dev(rbd_dev); | |
5280 | rbd_dev_image_release(rbd_dev); | |
5281 | module_put(THIS_MODULE); | |
5282 | ||
5283 | return count; | |
5284 | } | |
5285 | ||
5286 | static ssize_t rbd_remove(struct bus_type *bus, | |
5287 | const char *buf, | |
5288 | size_t count) | |
5289 | { | |
5290 | if (single_major) | |
5291 | return -EINVAL; | |
5292 | ||
5293 | return do_rbd_remove(bus, buf, count); | |
5294 | } | |
5295 | ||
5296 | static ssize_t rbd_remove_single_major(struct bus_type *bus, | |
5297 | const char *buf, | |
5298 | size_t count) | |
5299 | { | |
5300 | return do_rbd_remove(bus, buf, count); | |
5301 | } | |
5302 | ||
5303 | /* | |
5304 | * create control files in sysfs | |
5305 | * /sys/bus/rbd/... | |
5306 | */ | |
5307 | static int rbd_sysfs_init(void) | |
5308 | { | |
5309 | int ret; | |
5310 | ||
5311 | ret = device_register(&rbd_root_dev); | |
5312 | if (ret < 0) | |
5313 | return ret; | |
5314 | ||
5315 | ret = bus_register(&rbd_bus_type); | |
5316 | if (ret < 0) | |
5317 | device_unregister(&rbd_root_dev); | |
5318 | ||
5319 | return ret; | |
5320 | } | |
5321 | ||
5322 | static void rbd_sysfs_cleanup(void) | |
5323 | { | |
5324 | bus_unregister(&rbd_bus_type); | |
5325 | device_unregister(&rbd_root_dev); | |
5326 | } | |
5327 | ||
5328 | static int rbd_slab_init(void) | |
5329 | { | |
5330 | rbd_assert(!rbd_img_request_cache); | |
5331 | rbd_img_request_cache = kmem_cache_create("rbd_img_request", | |
5332 | sizeof (struct rbd_img_request), | |
5333 | __alignof__(struct rbd_img_request), | |
5334 | 0, NULL); | |
5335 | if (!rbd_img_request_cache) | |
5336 | return -ENOMEM; | |
5337 | ||
5338 | rbd_assert(!rbd_obj_request_cache); | |
5339 | rbd_obj_request_cache = kmem_cache_create("rbd_obj_request", | |
5340 | sizeof (struct rbd_obj_request), | |
5341 | __alignof__(struct rbd_obj_request), | |
5342 | 0, NULL); | |
5343 | if (!rbd_obj_request_cache) | |
5344 | goto out_err; | |
5345 | ||
5346 | rbd_assert(!rbd_segment_name_cache); | |
5347 | rbd_segment_name_cache = kmem_cache_create("rbd_segment_name", | |
5348 | CEPH_MAX_OID_NAME_LEN + 1, 1, 0, NULL); | |
5349 | if (rbd_segment_name_cache) | |
5350 | return 0; | |
5351 | out_err: | |
5352 | if (rbd_obj_request_cache) { | |
5353 | kmem_cache_destroy(rbd_obj_request_cache); | |
5354 | rbd_obj_request_cache = NULL; | |
5355 | } | |
5356 | ||
5357 | kmem_cache_destroy(rbd_img_request_cache); | |
5358 | rbd_img_request_cache = NULL; | |
5359 | ||
5360 | return -ENOMEM; | |
5361 | } | |
5362 | ||
5363 | static void rbd_slab_exit(void) | |
5364 | { | |
5365 | rbd_assert(rbd_segment_name_cache); | |
5366 | kmem_cache_destroy(rbd_segment_name_cache); | |
5367 | rbd_segment_name_cache = NULL; | |
5368 | ||
5369 | rbd_assert(rbd_obj_request_cache); | |
5370 | kmem_cache_destroy(rbd_obj_request_cache); | |
5371 | rbd_obj_request_cache = NULL; | |
5372 | ||
5373 | rbd_assert(rbd_img_request_cache); | |
5374 | kmem_cache_destroy(rbd_img_request_cache); | |
5375 | rbd_img_request_cache = NULL; | |
5376 | } | |
5377 | ||
5378 | static int __init rbd_init(void) | |
5379 | { | |
5380 | int rc; | |
5381 | ||
5382 | if (!libceph_compatible(NULL)) { | |
5383 | rbd_warn(NULL, "libceph incompatibility (quitting)"); | |
5384 | return -EINVAL; | |
5385 | } | |
5386 | ||
5387 | rc = rbd_slab_init(); | |
5388 | if (rc) | |
5389 | return rc; | |
5390 | ||
5391 | if (single_major) { | |
5392 | rbd_major = register_blkdev(0, RBD_DRV_NAME); | |
5393 | if (rbd_major < 0) { | |
5394 | rc = rbd_major; | |
5395 | goto err_out_slab; | |
5396 | } | |
5397 | } | |
5398 | ||
5399 | rc = rbd_sysfs_init(); | |
5400 | if (rc) | |
5401 | goto err_out_blkdev; | |
5402 | ||
5403 | if (single_major) | |
5404 | pr_info("loaded (major %d)\n", rbd_major); | |
5405 | else | |
5406 | pr_info("loaded\n"); | |
5407 | ||
5408 | return 0; | |
5409 | ||
5410 | err_out_blkdev: | |
5411 | if (single_major) | |
5412 | unregister_blkdev(rbd_major, RBD_DRV_NAME); | |
5413 | err_out_slab: | |
5414 | rbd_slab_exit(); | |
5415 | return rc; | |
5416 | } | |
5417 | ||
5418 | static void __exit rbd_exit(void) | |
5419 | { | |
5420 | rbd_sysfs_cleanup(); | |
5421 | if (single_major) | |
5422 | unregister_blkdev(rbd_major, RBD_DRV_NAME); | |
5423 | rbd_slab_exit(); | |
5424 | } | |
5425 | ||
5426 | module_init(rbd_init); | |
5427 | module_exit(rbd_exit); | |
5428 | ||
5429 | MODULE_AUTHOR("Alex Elder <elder@inktank.com>"); | |
5430 | MODULE_AUTHOR("Sage Weil <sage@newdream.net>"); | |
5431 | MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>"); | |
5432 | /* following authorship retained from original osdblk.c */ | |
5433 | MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>"); | |
5434 | ||
5435 | MODULE_DESCRIPTION("RADOS Block Device (RBD) driver"); | |
5436 | MODULE_LICENSE("GPL"); |