rbd.c 165.7 KB
Newer Older
1

2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
/*
   rbd.c -- Export ceph rados objects as a Linux block device


   based on drivers/block/osdblk.c:

   Copyright 2009 Red Hat, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; see the file COPYING.  If not, write to
   the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.



25
   For usage instructions, please refer to:
26

27
                 Documentation/ABI/testing/sysfs-bus-rbd
28 29 30 31 32 33

 */

#include <linux/ceph/libceph.h>
#include <linux/ceph/osd_client.h>
#include <linux/ceph/mon_client.h>
34
#include <linux/ceph/cls_lock_client.h>
35
#include <linux/ceph/decode.h>
36
#include <linux/parser.h>
37
#include <linux/bsearch.h>
38 39 40 41

#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/module.h>
C
Christoph Hellwig 已提交
42
#include <linux/blk-mq.h>
43 44
#include <linux/fs.h>
#include <linux/blkdev.h>
45
#include <linux/slab.h>
46
#include <linux/idr.h>
I
Ilya Dryomov 已提交
47
#include <linux/workqueue.h>
48 49 50

#include "rbd_types.h"

A
Alex Elder 已提交
51 52
#define RBD_DEBUG	/* Activate rbd_assert() calls */

A
Alex Elder 已提交
53 54 55 56 57 58 59 60 61
/*
 * The basic unit of block I/O is a sector.  It is interpreted in a
 * number of contexts in Linux (blk, bio, genhd), but the default is
 * universally 512 bytes.  These symbols are just slightly more
 * meaningful than the bare numbers they represent.
 */
#define	SECTOR_SHIFT	9
#define	SECTOR_SIZE	(1ULL << SECTOR_SHIFT)

62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94
/*
 * Increment the given counter and return its updated value.
 * If the counter is already 0 it will not be incremented.
 * If the counter is already at its maximum value returns
 * -EINVAL without updating it.
 */
static int atomic_inc_return_safe(atomic_t *v)
{
	unsigned int counter;

	counter = (unsigned int)__atomic_add_unless(v, 1, 0);
	if (counter <= (unsigned int)INT_MAX)
		return (int)counter;

	atomic_dec(v);

	return -EINVAL;
}

/* Decrement the counter.  Return the resulting value, or -EINVAL */
static int atomic_dec_return_safe(atomic_t *v)
{
	int counter;

	counter = atomic_dec_return(v);
	if (counter >= 0)
		return counter;

	atomic_inc(v);

	return -EINVAL;
}

A
Alex Elder 已提交
95
#define RBD_DRV_NAME "rbd"
96

97 98
#define RBD_MINORS_PER_MAJOR		256
#define RBD_SINGLE_MAJOR_PART_SHIFT	4
99

100 101
#define RBD_MAX_PARENT_CHAIN_LEN	16

102 103 104 105
#define RBD_SNAP_DEV_NAME_PREFIX	"snap_"
#define RBD_MAX_SNAP_NAME_LEN	\
			(NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1))

106
#define RBD_MAX_SNAP_COUNT	510	/* allows max snapc to fit in 4KB */
107 108 109

#define RBD_SNAP_HEAD_NAME	"-"

110 111
#define	BAD_SNAP_INDEX	U32_MAX		/* invalid index into snap array */

112 113
/* This allows a single page to hold an image name sent by OSD */
#define RBD_IMAGE_NAME_LEN_MAX	(PAGE_SIZE - sizeof (__le32) - 1)
114
#define RBD_IMAGE_ID_LEN_MAX	64
115

116
#define RBD_OBJ_PREFIX_LEN_MAX	64
A
Alex Elder 已提交
117

118
#define RBD_NOTIFY_TIMEOUT	5	/* seconds */
119 120
#define RBD_RETRY_DELAY		msecs_to_jiffies(1000)

A
Alex Elder 已提交
121 122
/* Feature bits */

123 124 125 126 127
#define RBD_FEATURE_LAYERING		(1ULL<<0)
#define RBD_FEATURE_STRIPINGV2		(1ULL<<1)
#define RBD_FEATURE_EXCLUSIVE_LOCK	(1ULL<<2)
#define RBD_FEATURE_DATA_POOL		(1ULL<<7)

128 129
#define RBD_FEATURES_ALL	(RBD_FEATURE_LAYERING |		\
				 RBD_FEATURE_STRIPINGV2 |	\
130 131
				 RBD_FEATURE_EXCLUSIVE_LOCK |	\
				 RBD_FEATURE_DATA_POOL)
A
Alex Elder 已提交
132 133 134

/* Features supported by this (client software) implementation. */

135
#define RBD_FEATURES_SUPPORTED	(RBD_FEATURES_ALL)
A
Alex Elder 已提交
136

A
Alex Elder 已提交
137 138 139 140
/*
 * An RBD device name will be "rbd#", where the "rbd" comes from
 * RBD_DRV_NAME above, and # is a unique integer identifier.
 */
141 142 143 144 145 146
#define DEV_NAME_LEN		32

/*
 * block device image metadata (in-memory version)
 */
struct rbd_image_header {
147
	/* These six fields never change for a given rbd image */
148
	char *object_prefix;
149
	__u8 obj_order;
150 151
	u64 stripe_unit;
	u64 stripe_count;
152
	s64 data_pool_id;
153
	u64 features;		/* Might be changeable someday? */
154

A
Alex Elder 已提交
155 156 157
	/* The remaining fields need to be updated occasionally */
	u64 image_size;
	struct ceph_snap_context *snapc;
158 159
	char *snap_names;	/* format 1 only */
	u64 *snap_sizes;	/* format 1 only */
160 161
};

162 163 164 165
/*
 * An rbd image specification.
 *
 * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely
A
Alex Elder 已提交
166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185
 * identify an image.  Each rbd_dev structure includes a pointer to
 * an rbd_spec structure that encapsulates this identity.
 *
 * Each of the id's in an rbd_spec has an associated name.  For a
 * user-mapped image, the names are supplied and the id's associated
 * with them are looked up.  For a layered image, a parent image is
 * defined by the tuple, and the names are looked up.
 *
 * An rbd_dev structure contains a parent_spec pointer which is
 * non-null if the image it represents is a child in a layered
 * image.  This pointer will refer to the rbd_spec structure used
 * by the parent rbd_dev for its own identity (i.e., the structure
 * is shared between the parent and child).
 *
 * Since these structures are populated once, during the discovery
 * phase of image construction, they are effectively immutable so
 * we make no effort to synchronize access to them.
 *
 * Note that code herein does not assume the image name is known (it
 * could be a null pointer).
186 187 188
 */
struct rbd_spec {
	u64		pool_id;
189
	const char	*pool_name;
190

191 192
	const char	*image_id;
	const char	*image_name;
193 194

	u64		snap_id;
195
	const char	*snap_name;
196 197 198 199

	struct kref	kref;
};

200
/*
A
Alex Elder 已提交
201
 * an instance of the client.  multiple devices may share an rbd client.
202 203 204 205 206 207 208
 */
struct rbd_client {
	struct ceph_client	*client;
	struct kref		kref;
	struct list_head	node;
};

A
Alex Elder 已提交
209 210 211 212 213 214 215 216
struct rbd_img_request;
typedef void (*rbd_img_callback_t)(struct rbd_img_request *);

#define	BAD_WHICH	U32_MAX		/* Good which or bad which, which? */

struct rbd_obj_request;
typedef void (*rbd_obj_callback_t)(struct rbd_obj_request *);

217 218 219
enum obj_request_type {
	OBJ_REQUEST_NODATA, OBJ_REQUEST_BIO, OBJ_REQUEST_PAGES
};
A
Alex Elder 已提交
220

G
Guangliang Zhao 已提交
221 222 223
enum obj_operation_type {
	OBJ_OP_WRITE,
	OBJ_OP_READ,
224
	OBJ_OP_DISCARD,
G
Guangliang Zhao 已提交
225 226
};

227 228
enum obj_req_flags {
	OBJ_REQ_DONE,		/* completion flag: not done = 0, done = 1 */
229
	OBJ_REQ_IMG_DATA,	/* object usage: standalone = 0, image = 1 */
230 231
	OBJ_REQ_KNOWN,		/* EXISTS flag valid: no = 0, yes = 1 */
	OBJ_REQ_EXISTS,		/* target exists: no = 0, yes = 1 */
232 233
};

A
Alex Elder 已提交
234
struct rbd_obj_request {
235
	u64			object_no;
A
Alex Elder 已提交
236 237
	u64			offset;		/* object start byte */
	u64			length;		/* bytes from offset */
238
	unsigned long		flags;
A
Alex Elder 已提交
239

240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264
	/*
	 * An object request associated with an image will have its
	 * img_data flag set; a standalone object request will not.
	 *
	 * A standalone object request will have which == BAD_WHICH
	 * and a null obj_request pointer.
	 *
	 * An object request initiated in support of a layered image
	 * object (to check for its existence before a write) will
	 * have which == BAD_WHICH and a non-null obj_request pointer.
	 *
	 * Finally, an object request for rbd image data will have
	 * which != BAD_WHICH, and will have a non-null img_request
	 * pointer.  The value of which will be in the range
	 * 0..(img_request->obj_request_count-1).
	 */
	union {
		struct rbd_obj_request	*obj_request;	/* STAT op */
		struct {
			struct rbd_img_request	*img_request;
			u64			img_offset;
			/* links for img_request->obj_requests list */
			struct list_head	links;
		};
	};
A
Alex Elder 已提交
265 266 267
	u32			which;		/* posn image request list */

	enum obj_request_type	type;
268 269 270 271 272 273 274
	union {
		struct bio	*bio_list;
		struct {
			struct page	**pages;
			u32		page_count;
		};
	};
275
	struct page		**copyup_pages;
276
	u32			copyup_page_count;
A
Alex Elder 已提交
277 278 279 280

	struct ceph_osd_request	*osd_req;

	u64			xferred;	/* bytes transferred */
281
	int			result;
A
Alex Elder 已提交
282 283

	rbd_obj_callback_t	callback;
284
	struct completion	completion;
A
Alex Elder 已提交
285 286 287 288

	struct kref		kref;
};

A
Alex Elder 已提交
289
enum img_req_flags {
290 291
	IMG_REQ_WRITE,		/* I/O direction: read = 0, write = 1 */
	IMG_REQ_CHILD,		/* initiator: block = 0, child image = 1 */
292
	IMG_REQ_LAYERED,	/* ENOENT handling: normal = 0, layered = 1 */
293
	IMG_REQ_DISCARD,	/* discard: normal = 0, discard request = 1 */
A
Alex Elder 已提交
294 295
};

A
Alex Elder 已提交
296 297 298 299
struct rbd_img_request {
	struct rbd_device	*rbd_dev;
	u64			offset;	/* starting image byte offset */
	u64			length;	/* byte count from offset */
A
Alex Elder 已提交
300
	unsigned long		flags;
A
Alex Elder 已提交
301
	union {
302
		u64			snap_id;	/* for reads */
A
Alex Elder 已提交
303
		struct ceph_snap_context *snapc;	/* for writes */
304 305 306 307
	};
	union {
		struct request		*rq;		/* block request */
		struct rbd_obj_request	*obj_request;	/* obj req initiator */
A
Alex Elder 已提交
308
	};
309
	struct page		**copyup_pages;
310
	u32			copyup_page_count;
A
Alex Elder 已提交
311 312 313
	spinlock_t		completion_lock;/* protects next_completion */
	u32			next_completion;
	rbd_img_callback_t	callback;
314
	u64			xferred;/* aggregate bytes transferred */
315
	int			result;	/* first nonzero obj_request result */
A
Alex Elder 已提交
316 317 318 319 320 321 322 323

	u32			obj_request_count;
	struct list_head	obj_requests;	/* rbd_obj_request structs */

	struct kref		kref;
};

#define for_each_obj_request(ireq, oreq) \
324
	list_for_each_entry(oreq, &(ireq)->obj_requests, links)
A
Alex Elder 已提交
325
#define for_each_obj_request_from(ireq, oreq) \
326
	list_for_each_entry_from(oreq, &(ireq)->obj_requests, links)
A
Alex Elder 已提交
327
#define for_each_obj_request_safe(ireq, oreq, n) \
328
	list_for_each_entry_safe_reverse(oreq, n, &(ireq)->obj_requests, links)
A
Alex Elder 已提交
329

330 331 332 333 334 335
enum rbd_watch_state {
	RBD_WATCH_STATE_UNREGISTERED,
	RBD_WATCH_STATE_REGISTERED,
	RBD_WATCH_STATE_ERROR,
};

336 337 338 339 340 341 342 343 344 345 346 347
enum rbd_lock_state {
	RBD_LOCK_STATE_UNLOCKED,
	RBD_LOCK_STATE_LOCKED,
	RBD_LOCK_STATE_RELEASING,
};

/* WatchNotify::ClientId */
struct rbd_client_id {
	u64 gid;
	u64 handle;
};

A
Alex Elder 已提交
348
struct rbd_mapping {
A
Alex Elder 已提交
349
	u64                     size;
A
Alex Elder 已提交
350
	u64                     features;
A
Alex Elder 已提交
351 352
};

353 354 355 356
/*
 * a single device
 */
struct rbd_device {
A
Alex Elder 已提交
357
	int			dev_id;		/* blkdev unique id */
358 359

	int			major;		/* blkdev assigned major */
360
	int			minor;
361 362
	struct gendisk		*disk;		/* blkdev's gendisk and rq */

363
	u32			image_format;	/* Either 1 or 2 */
364 365 366 367
	struct rbd_client	*rbd_client;

	char			name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */

368
	spinlock_t		lock;		/* queue, flags, open_count */
369 370

	struct rbd_image_header	header;
371
	unsigned long		flags;		/* possibly lock protected */
372
	struct rbd_spec		*spec;
373
	struct rbd_options	*opts;
374
	char			*config_info;	/* add{,_single_major} string */
375

376
	struct ceph_object_id	header_oid;
377
	struct ceph_object_locator header_oloc;
378

379
	struct ceph_file_layout	layout;		/* used for all rbd requests */
380

381 382
	struct mutex		watch_mutex;
	enum rbd_watch_state	watch_state;
383
	struct ceph_osd_linger_request *watch_handle;
384 385
	u64			watch_cookie;
	struct delayed_work	watch_dwork;
386

387 388
	struct rw_semaphore	lock_rwsem;
	enum rbd_lock_state	lock_state;
I
Ilya Dryomov 已提交
389
	char			lock_cookie[32];
390 391 392 393 394 395 396
	struct rbd_client_id	owner_cid;
	struct work_struct	acquired_lock_work;
	struct work_struct	released_lock_work;
	struct delayed_work	lock_dwork;
	struct work_struct	unlock_work;
	wait_queue_head_t	lock_waitq;

397
	struct workqueue_struct	*task_wq;
398

399 400
	struct rbd_spec		*parent_spec;
	u64			parent_overlap;
401
	atomic_t		parent_ref;
402
	struct rbd_device	*parent;
403

C
Christoph Hellwig 已提交
404 405 406
	/* Block layer tags. */
	struct blk_mq_tag_set	tag_set;

407 408
	/* protects updating the header */
	struct rw_semaphore     header_rwsem;
A
Alex Elder 已提交
409 410

	struct rbd_mapping	mapping;
411 412

	struct list_head	node;
413 414 415

	/* sysfs related */
	struct device		dev;
416
	unsigned long		open_count;	/* protected by lock */
417 418
};

419
/*
420 421 422 423
 * Flag bits for rbd_dev->flags:
 * - REMOVING (which is coupled with rbd_dev->open_count) is protected
 *   by rbd_dev->lock
 * - BLACKLISTED is protected by rbd_dev->lock_rwsem
424
 */
425 426
enum rbd_dev_flags {
	RBD_DEV_FLAG_EXISTS,	/* mapped snapshot has not been deleted */
427
	RBD_DEV_FLAG_REMOVING,	/* this mapping is being removed */
428
	RBD_DEV_FLAG_BLACKLISTED, /* our ceph_client is blacklisted */
429 430
};

431
static DEFINE_MUTEX(client_mutex);	/* Serialize client creation */
432

433
static LIST_HEAD(rbd_dev_list);    /* devices */
434 435
static DEFINE_SPINLOCK(rbd_dev_list_lock);

A
Alex Elder 已提交
436 437
static LIST_HEAD(rbd_client_list);		/* clients */
static DEFINE_SPINLOCK(rbd_client_list_lock);
438

439 440
/* Slab caches for frequently-allocated structures */

441
static struct kmem_cache	*rbd_img_request_cache;
442
static struct kmem_cache	*rbd_obj_request_cache;
443

444 445
static struct bio_set		*rbd_bio_clone;

446
static int rbd_major;
447 448
static DEFINE_IDA(rbd_dev_id_ida);

449 450
static struct workqueue_struct *rbd_wq;

451
/*
452
 * single-major requires >= 0.75 version of userspace rbd utility.
453
 */
454
static bool single_major = true;
455
module_param(single_major, bool, S_IRUGO);
456
MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: true)");
457

458 459
static int rbd_img_request_submit(struct rbd_img_request *img_request);

A
Alex Elder 已提交
460 461 462 463
static ssize_t rbd_add(struct bus_type *bus, const char *buf,
		       size_t count);
static ssize_t rbd_remove(struct bus_type *bus, const char *buf,
			  size_t count);
464 465 466 467
static ssize_t rbd_add_single_major(struct bus_type *bus, const char *buf,
				    size_t count);
static ssize_t rbd_remove_single_major(struct bus_type *bus, const char *buf,
				       size_t count);
468
static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth);
469
static void rbd_spec_put(struct rbd_spec *spec);
A
Alex Elder 已提交
470

471 472
static int rbd_dev_id_to_minor(int dev_id)
{
473
	return dev_id << RBD_SINGLE_MAJOR_PART_SHIFT;
474 475 476 477
}

static int minor_to_rbd_dev_id(int minor)
{
478
	return minor >> RBD_SINGLE_MAJOR_PART_SHIFT;
479 480
}

481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496
static bool __rbd_is_lock_owner(struct rbd_device *rbd_dev)
{
	return rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED ||
	       rbd_dev->lock_state == RBD_LOCK_STATE_RELEASING;
}

static bool rbd_is_lock_owner(struct rbd_device *rbd_dev)
{
	bool is_lock_owner;

	down_read(&rbd_dev->lock_rwsem);
	is_lock_owner = __rbd_is_lock_owner(rbd_dev);
	up_read(&rbd_dev->lock_rwsem);
	return is_lock_owner;
}

497 498 499 500 501
static ssize_t rbd_supported_features_show(struct bus_type *bus, char *buf)
{
	return sprintf(buf, "0x%llx\n", RBD_FEATURES_SUPPORTED);
}

502 503
static BUS_ATTR(add, S_IWUSR, NULL, rbd_add);
static BUS_ATTR(remove, S_IWUSR, NULL, rbd_remove);
504 505
static BUS_ATTR(add_single_major, S_IWUSR, NULL, rbd_add_single_major);
static BUS_ATTR(remove_single_major, S_IWUSR, NULL, rbd_remove_single_major);
506
static BUS_ATTR(supported_features, S_IRUGO, rbd_supported_features_show, NULL);
507 508 509 510

static struct attribute *rbd_bus_attrs[] = {
	&bus_attr_add.attr,
	&bus_attr_remove.attr,
511 512
	&bus_attr_add_single_major.attr,
	&bus_attr_remove_single_major.attr,
513
	&bus_attr_supported_features.attr,
514
	NULL,
A
Alex Elder 已提交
515
};
516 517 518 519

static umode_t rbd_bus_is_visible(struct kobject *kobj,
				  struct attribute *attr, int index)
{
520 521 522 523 524
	if (!single_major &&
	    (attr == &bus_attr_add_single_major.attr ||
	     attr == &bus_attr_remove_single_major.attr))
		return 0;

525 526 527 528 529 530 531 532
	return attr->mode;
}

static const struct attribute_group rbd_bus_group = {
	.attrs = rbd_bus_attrs,
	.is_visible = rbd_bus_is_visible,
};
__ATTRIBUTE_GROUPS(rbd_bus);
A
Alex Elder 已提交
533 534 535

static struct bus_type rbd_bus_type = {
	.name		= "rbd",
536
	.bus_groups	= rbd_bus_groups,
A
Alex Elder 已提交
537 538 539 540 541 542 543 544 545 546 547
};

static void rbd_root_dev_release(struct device *dev)
{
}

static struct device rbd_root_dev = {
	.init_name =    "rbd",
	.release =      rbd_root_dev_release,
};

A
Alex Elder 已提交
548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574
static __printf(2, 3)
void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...)
{
	struct va_format vaf;
	va_list args;

	va_start(args, fmt);
	vaf.fmt = fmt;
	vaf.va = &args;

	if (!rbd_dev)
		printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf);
	else if (rbd_dev->disk)
		printk(KERN_WARNING "%s: %s: %pV\n",
			RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf);
	else if (rbd_dev->spec && rbd_dev->spec->image_name)
		printk(KERN_WARNING "%s: image %s: %pV\n",
			RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf);
	else if (rbd_dev->spec && rbd_dev->spec->image_id)
		printk(KERN_WARNING "%s: id %s: %pV\n",
			RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf);
	else	/* punt */
		printk(KERN_WARNING "%s: rbd_dev %p: %pV\n",
			RBD_DRV_NAME, rbd_dev, &vaf);
	va_end(args);
}

A
Alex Elder 已提交
575 576 577 578 579 580 581 582 583 584 585 586
#ifdef RBD_DEBUG
#define rbd_assert(expr)						\
		if (unlikely(!(expr))) {				\
			printk(KERN_ERR "\nAssertion failure in %s() "	\
						"at line %d:\n\n"	\
					"\trbd_assert(%s);\n\n",	\
					__func__, __LINE__, #expr);	\
			BUG();						\
		}
#else /* !RBD_DEBUG */
#  define rbd_assert(expr)	((void) 0)
#endif /* !RBD_DEBUG */
587

I
Ilya Dryomov 已提交
588
static void rbd_osd_copyup_callback(struct rbd_obj_request *obj_request);
589
static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request);
590 591
static void rbd_img_parent_read(struct rbd_obj_request *obj_request);
static void rbd_dev_remove_parent(struct rbd_device *rbd_dev);
A
Alex Elder 已提交
592

A
Alex Elder 已提交
593
static int rbd_dev_refresh(struct rbd_device *rbd_dev);
594
static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev);
595
static int rbd_dev_header_info(struct rbd_device *rbd_dev);
596
static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev);
597 598
static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
					u64 snap_id);
599 600 601 602
static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
				u8 *order, u64 *snap_size);
static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
		u64 *snap_features);
603

604 605
static int rbd_open(struct block_device *bdev, fmode_t mode)
{
A
Alex Elder 已提交
606
	struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
607
	bool removing = false;
608

609
	spin_lock_irq(&rbd_dev->lock);
610 611 612 613
	if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags))
		removing = true;
	else
		rbd_dev->open_count++;
614
	spin_unlock_irq(&rbd_dev->lock);
615 616 617
	if (removing)
		return -ENOENT;

A
Alex Elder 已提交
618
	(void) get_device(&rbd_dev->dev);
619

620 621 622
	return 0;
}

623
static void rbd_release(struct gendisk *disk, fmode_t mode)
624 625
{
	struct rbd_device *rbd_dev = disk->private_data;
626 627
	unsigned long open_count_before;

628
	spin_lock_irq(&rbd_dev->lock);
629
	open_count_before = rbd_dev->open_count--;
630
	spin_unlock_irq(&rbd_dev->lock);
631
	rbd_assert(open_count_before > 0);
632

A
Alex Elder 已提交
633
	put_device(&rbd_dev->dev);
634 635
}

G
Guangliang Zhao 已提交
636 637
static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg)
{
638
	int ro;
G
Guangliang Zhao 已提交
639

640
	if (get_user(ro, (int __user *)arg))
G
Guangliang Zhao 已提交
641 642
		return -EFAULT;

643
	/* Snapshots can't be marked read-write */
G
Guangliang Zhao 已提交
644 645 646
	if (rbd_dev->spec->snap_id != CEPH_NOSNAP && !ro)
		return -EROFS;

647 648
	/* Let blkdev_roset() handle it */
	return -ENOTTY;
G
Guangliang Zhao 已提交
649 650 651 652 653 654
}

static int rbd_ioctl(struct block_device *bdev, fmode_t mode,
			unsigned int cmd, unsigned long arg)
{
	struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
655
	int ret;
G
Guangliang Zhao 已提交
656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675

	switch (cmd) {
	case BLKROSET:
		ret = rbd_ioctl_set_ro(rbd_dev, arg);
		break;
	default:
		ret = -ENOTTY;
	}

	return ret;
}

#ifdef CONFIG_COMPAT
static int rbd_compat_ioctl(struct block_device *bdev, fmode_t mode,
				unsigned int cmd, unsigned long arg)
{
	return rbd_ioctl(bdev, mode, cmd, arg);
}
#endif /* CONFIG_COMPAT */

676 677 678
static const struct block_device_operations rbd_bd_ops = {
	.owner			= THIS_MODULE,
	.open			= rbd_open,
679
	.release		= rbd_release,
G
Guangliang Zhao 已提交
680 681 682 683
	.ioctl			= rbd_ioctl,
#ifdef CONFIG_COMPAT
	.compat_ioctl		= rbd_compat_ioctl,
#endif
684 685 686
};

/*
687
 * Initialize an rbd client instance.  Success or not, this function
688
 * consumes ceph_opts.  Caller holds client_mutex.
689
 */
690
static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts)
691 692 693 694
{
	struct rbd_client *rbdc;
	int ret = -ENOMEM;

A
Alex Elder 已提交
695
	dout("%s:\n", __func__);
696 697 698 699 700 701 702
	rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL);
	if (!rbdc)
		goto out_opt;

	kref_init(&rbdc->kref);
	INIT_LIST_HEAD(&rbdc->node);

703
	rbdc->client = ceph_create_client(ceph_opts, rbdc);
704
	if (IS_ERR(rbdc->client))
705
		goto out_rbdc;
A
Alex Elder 已提交
706
	ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */
707 708 709

	ret = ceph_open_session(rbdc->client);
	if (ret < 0)
710
		goto out_client;
711

A
Alex Elder 已提交
712
	spin_lock(&rbd_client_list_lock);
713
	list_add_tail(&rbdc->node, &rbd_client_list);
A
Alex Elder 已提交
714
	spin_unlock(&rbd_client_list_lock);
715

A
Alex Elder 已提交
716
	dout("%s: rbdc %p\n", __func__, rbdc);
717

718
	return rbdc;
719
out_client:
720
	ceph_destroy_client(rbdc->client);
721
out_rbdc:
722 723
	kfree(rbdc);
out_opt:
A
Alex Elder 已提交
724 725
	if (ceph_opts)
		ceph_destroy_options(ceph_opts);
A
Alex Elder 已提交
726 727
	dout("%s: error %d\n", __func__, ret);

V
Vasiliy Kulikov 已提交
728
	return ERR_PTR(ret);
729 730
}

731 732 733 734 735 736 737
static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc)
{
	kref_get(&rbdc->kref);

	return rbdc;
}

738
/*
739 740
 * Find a ceph client with specific addr and configuration.  If
 * found, bump its reference count.
741
 */
742
static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts)
743 744
{
	struct rbd_client *client_node;
745
	bool found = false;
746

A
Alex Elder 已提交
747
	if (ceph_opts->flags & CEPH_OPT_NOSHARE)
748 749
		return NULL;

750 751 752
	spin_lock(&rbd_client_list_lock);
	list_for_each_entry(client_node, &rbd_client_list, node) {
		if (!ceph_compare_options(ceph_opts, client_node->client)) {
753 754
			__rbd_get_client(client_node);

755 756 757 758 759 760 761
			found = true;
			break;
		}
	}
	spin_unlock(&rbd_client_list_lock);

	return found ? client_node : NULL;
762 763
}

764
/*
765
 * (Per device) rbd map options
766 767
 */
enum {
I
Ilya Dryomov 已提交
768
	Opt_queue_depth,
769 770 771 772
	Opt_last_int,
	/* int args above */
	Opt_last_string,
	/* string args above */
A
Alex Elder 已提交
773 774
	Opt_read_only,
	Opt_read_write,
I
Ilya Dryomov 已提交
775
	Opt_lock_on_read,
I
Ilya Dryomov 已提交
776
	Opt_exclusive,
777
	Opt_err
778 779
};

A
Alex Elder 已提交
780
static match_table_t rbd_opts_tokens = {
I
Ilya Dryomov 已提交
781
	{Opt_queue_depth, "queue_depth=%d"},
782 783
	/* int args above */
	/* string args above */
A
Alex Elder 已提交
784
	{Opt_read_only, "read_only"},
A
Alex Elder 已提交
785 786 787
	{Opt_read_only, "ro"},		/* Alternate spelling */
	{Opt_read_write, "read_write"},
	{Opt_read_write, "rw"},		/* Alternate spelling */
I
Ilya Dryomov 已提交
788
	{Opt_lock_on_read, "lock_on_read"},
I
Ilya Dryomov 已提交
789
	{Opt_exclusive, "exclusive"},
790
	{Opt_err, NULL}
791 792
};

A
Alex Elder 已提交
793
struct rbd_options {
I
Ilya Dryomov 已提交
794
	int	queue_depth;
A
Alex Elder 已提交
795
	bool	read_only;
I
Ilya Dryomov 已提交
796
	bool	lock_on_read;
I
Ilya Dryomov 已提交
797
	bool	exclusive;
A
Alex Elder 已提交
798 799
};

I
Ilya Dryomov 已提交
800
#define RBD_QUEUE_DEPTH_DEFAULT	BLKDEV_MAX_RQ
A
Alex Elder 已提交
801
#define RBD_READ_ONLY_DEFAULT	false
I
Ilya Dryomov 已提交
802
#define RBD_LOCK_ON_READ_DEFAULT false
I
Ilya Dryomov 已提交
803
#define RBD_EXCLUSIVE_DEFAULT	false
A
Alex Elder 已提交
804

805 806
static int parse_rbd_opts_token(char *c, void *private)
{
A
Alex Elder 已提交
807
	struct rbd_options *rbd_opts = private;
808 809 810
	substring_t argstr[MAX_OPT_ARGS];
	int token, intval, ret;

A
Alex Elder 已提交
811
	token = match_token(c, rbd_opts_tokens, argstr);
812 813 814
	if (token < Opt_last_int) {
		ret = match_int(&argstr[0], &intval);
		if (ret < 0) {
815
			pr_err("bad mount option arg (not int) at '%s'\n", c);
816 817 818 819
			return ret;
		}
		dout("got int token %d val %d\n", token, intval);
	} else if (token > Opt_last_int && token < Opt_last_string) {
820
		dout("got string token %d val %s\n", token, argstr[0].from);
821 822 823 824 825
	} else {
		dout("got token %d\n", token);
	}

	switch (token) {
I
Ilya Dryomov 已提交
826 827 828 829 830 831 832
	case Opt_queue_depth:
		if (intval < 1) {
			pr_err("queue_depth out of range\n");
			return -EINVAL;
		}
		rbd_opts->queue_depth = intval;
		break;
A
Alex Elder 已提交
833 834 835 836 837 838
	case Opt_read_only:
		rbd_opts->read_only = true;
		break;
	case Opt_read_write:
		rbd_opts->read_only = false;
		break;
I
Ilya Dryomov 已提交
839 840 841
	case Opt_lock_on_read:
		rbd_opts->lock_on_read = true;
		break;
I
Ilya Dryomov 已提交
842 843 844
	case Opt_exclusive:
		rbd_opts->exclusive = true;
		break;
845
	default:
846 847
		/* libceph prints "bad option" msg */
		return -EINVAL;
848
	}
849

850 851 852
	return 0;
}

G
Guangliang Zhao 已提交
853 854 855 856 857 858 859
static char* obj_op_name(enum obj_operation_type op_type)
{
	switch (op_type) {
	case OBJ_OP_READ:
		return "read";
	case OBJ_OP_WRITE:
		return "write";
860 861
	case OBJ_OP_DISCARD:
		return "discard";
G
Guangliang Zhao 已提交
862 863 864 865 866
	default:
		return "???";
	}
}

867 868
/*
 * Get a ceph client with specific addr and configuration, if one does
869 870
 * not exist create it.  Either way, ceph_opts is consumed by this
 * function.
871
 */
872
static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts)
873
{
874
	struct rbd_client *rbdc;
875

876
	mutex_lock_nested(&client_mutex, SINGLE_DEPTH_NESTING);
877
	rbdc = rbd_client_find(ceph_opts);
878
	if (rbdc)	/* using an existing client */
A
Alex Elder 已提交
879
		ceph_destroy_options(ceph_opts);
880
	else
881
		rbdc = rbd_client_create(ceph_opts);
882
	mutex_unlock(&client_mutex);
883

884
	return rbdc;
885 886 887 888
}

/*
 * Destroy ceph client
A
Alex Elder 已提交
889
 *
A
Alex Elder 已提交
890
 * Caller must hold rbd_client_list_lock.
891 892 893 894 895
 */
static void rbd_client_release(struct kref *kref)
{
	struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref);

A
Alex Elder 已提交
896
	dout("%s: rbdc %p\n", __func__, rbdc);
897
	spin_lock(&rbd_client_list_lock);
898
	list_del(&rbdc->node);
899
	spin_unlock(&rbd_client_list_lock);
900 901 902 903 904 905 906 907 908

	ceph_destroy_client(rbdc->client);
	kfree(rbdc);
}

/*
 * Drop reference to ceph client node. If it's not referenced anymore, release
 * it.
 */
909
static void rbd_put_client(struct rbd_client *rbdc)
910
{
911 912
	if (rbdc)
		kref_put(&rbdc->kref, rbd_client_release);
913 914
}

915 916 917 918 919
static bool rbd_image_format_valid(u32 image_format)
{
	return image_format == 1 || image_format == 2;
}

920 921
static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk)
{
922 923 924 925 926 927 928
	size_t size;
	u32 snap_count;

	/* The header has to start with the magic rbd header text */
	if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT)))
		return false;

A
Alex Elder 已提交
929 930 931 932 933 934 935 936 937 938
	/* The bio layer requires at least sector-sized I/O */

	if (ondisk->options.order < SECTOR_SHIFT)
		return false;

	/* If we use u64 in a few spots we may be able to loosen this */

	if (ondisk->options.order > 8 * sizeof (int) - 1)
		return false;

939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956
	/*
	 * The size of a snapshot header has to fit in a size_t, and
	 * that limits the number of snapshots.
	 */
	snap_count = le32_to_cpu(ondisk->snap_count);
	size = SIZE_MAX - sizeof (struct ceph_snap_context);
	if (snap_count > size / sizeof (__le64))
		return false;

	/*
	 * Not only that, but the size of the entire the snapshot
	 * header must also be representable in a size_t.
	 */
	size -= snap_count * sizeof (__le64);
	if ((u64) size < le64_to_cpu(ondisk->snap_names_len))
		return false;

	return true;
957 958
}

I
Ilya Dryomov 已提交
959 960 961 962 963 964 965 966
/*
 * returns the size of an object in the image
 */
static u32 rbd_obj_bytes(struct rbd_image_header *header)
{
	return 1U << header->obj_order;
}

I
Ilya Dryomov 已提交
967 968 969 970 971 972 973 974 975 976 977
static void rbd_init_layout(struct rbd_device *rbd_dev)
{
	if (rbd_dev->header.stripe_unit == 0 ||
	    rbd_dev->header.stripe_count == 0) {
		rbd_dev->header.stripe_unit = rbd_obj_bytes(&rbd_dev->header);
		rbd_dev->header.stripe_count = 1;
	}

	rbd_dev->layout.stripe_unit = rbd_dev->header.stripe_unit;
	rbd_dev->layout.stripe_count = rbd_dev->header.stripe_count;
	rbd_dev->layout.object_size = rbd_obj_bytes(&rbd_dev->header);
978 979
	rbd_dev->layout.pool_id = rbd_dev->header.data_pool_id == CEPH_NOPOOL ?
			  rbd_dev->spec->pool_id : rbd_dev->header.data_pool_id;
I
Ilya Dryomov 已提交
980 981 982
	RCU_INIT_POINTER(rbd_dev->layout.pool_ns, NULL);
}

983
/*
984 985
 * Fill an rbd image header with information from the given format 1
 * on-disk header.
986
 */
A
Alex Elder 已提交
987
static int rbd_header_from_disk(struct rbd_device *rbd_dev,
988
				 struct rbd_image_header_ondisk *ondisk)
989
{
A
Alex Elder 已提交
990
	struct rbd_image_header *header = &rbd_dev->header;
991 992 993 994 995
	bool first_time = header->object_prefix == NULL;
	struct ceph_snap_context *snapc;
	char *object_prefix = NULL;
	char *snap_names = NULL;
	u64 *snap_sizes = NULL;
996
	u32 snap_count;
997
	int ret = -ENOMEM;
998
	u32 i;
999

1000
	/* Allocate this now to avoid having to handle failure below */
A
Alex Elder 已提交
1001

1002
	if (first_time) {
1003 1004 1005
		object_prefix = kstrndup(ondisk->object_prefix,
					 sizeof(ondisk->object_prefix),
					 GFP_KERNEL);
1006 1007 1008
		if (!object_prefix)
			return -ENOMEM;
	}
A
Alex Elder 已提交
1009

1010
	/* Allocate the snapshot context and fill it in */
A
Alex Elder 已提交
1011

1012 1013 1014 1015 1016
	snap_count = le32_to_cpu(ondisk->snap_count);
	snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
	if (!snapc)
		goto out_err;
	snapc->seq = le64_to_cpu(ondisk->snap_seq);
1017
	if (snap_count) {
1018
		struct rbd_image_snap_ondisk *snaps;
A
Alex Elder 已提交
1019 1020
		u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);

1021
		/* We'll keep a copy of the snapshot names... */
1022

1023 1024 1025 1026
		if (snap_names_len > (u64)SIZE_MAX)
			goto out_2big;
		snap_names = kmalloc(snap_names_len, GFP_KERNEL);
		if (!snap_names)
A
Alex Elder 已提交
1027 1028
			goto out_err;

1029
		/* ...as well as the array of their sizes. */
1030 1031 1032
		snap_sizes = kmalloc_array(snap_count,
					   sizeof(*header->snap_sizes),
					   GFP_KERNEL);
1033
		if (!snap_sizes)
A
Alex Elder 已提交
1034
			goto out_err;
1035

A
Alex Elder 已提交
1036
		/*
1037 1038 1039
		 * Copy the names, and fill in each snapshot's id
		 * and size.
		 *
1040
		 * Note that rbd_dev_v1_header_info() guarantees the
1041
		 * ondisk buffer we're working with has
A
Alex Elder 已提交
1042 1043 1044
		 * snap_names_len bytes beyond the end of the
		 * snapshot id array, this memcpy() is safe.
		 */
1045 1046 1047 1048 1049 1050
		memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len);
		snaps = ondisk->snaps;
		for (i = 0; i < snap_count; i++) {
			snapc->snaps[i] = le64_to_cpu(snaps[i].id);
			snap_sizes[i] = le64_to_cpu(snaps[i].image_size);
		}
1051
	}
A
Alex Elder 已提交
1052

1053
	/* We won't fail any more, fill in the header */
1054

1055 1056 1057
	if (first_time) {
		header->object_prefix = object_prefix;
		header->obj_order = ondisk->options.order;
I
Ilya Dryomov 已提交
1058
		rbd_init_layout(rbd_dev);
1059
	} else {
A
Alex Elder 已提交
1060 1061 1062
		ceph_put_snap_context(header->snapc);
		kfree(header->snap_names);
		kfree(header->snap_sizes);
1063
	}
1064

1065
	/* The remaining fields always get updated (when we refresh) */
1066

A
Alex Elder 已提交
1067
	header->image_size = le64_to_cpu(ondisk->image_size);
1068 1069 1070
	header->snapc = snapc;
	header->snap_names = snap_names;
	header->snap_sizes = snap_sizes;
1071

1072
	return 0;
1073 1074
out_2big:
	ret = -EIO;
A
Alex Elder 已提交
1075
out_err:
1076 1077 1078 1079
	kfree(snap_sizes);
	kfree(snap_names);
	ceph_put_snap_context(snapc);
	kfree(object_prefix);
1080

1081
	return ret;
1082 1083
}

1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098
static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
{
	const char *snap_name;

	rbd_assert(which < rbd_dev->header.snapc->num_snaps);

	/* Skip over names until we find the one we are looking for */

	snap_name = rbd_dev->header.snap_names;
	while (which--)
		snap_name += strlen(snap_name) + 1;

	return kstrdup(snap_name, GFP_KERNEL);
}

1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122
/*
 * Snapshot id comparison function for use with qsort()/bsearch().
 * Note that result is for snapshots in *descending* order.
 */
static int snapid_compare_reverse(const void *s1, const void *s2)
{
	u64 snap_id1 = *(u64 *)s1;
	u64 snap_id2 = *(u64 *)s2;

	if (snap_id1 < snap_id2)
		return 1;
	return snap_id1 == snap_id2 ? 0 : -1;
}

/*
 * Search a snapshot context to see if the given snapshot id is
 * present.
 *
 * Returns the position of the snapshot id in the array if it's found,
 * or BAD_SNAP_INDEX otherwise.
 *
 * Note: The snapshot array is in kept sorted (by the osd) in
 * reverse order, highest snapshot id first.
 */
1123 1124 1125
static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id)
{
	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
1126
	u64 *found;
1127

1128 1129
	found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps,
				sizeof (snap_id), snapid_compare_reverse);
1130

1131
	return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX;
1132 1133
}

1134 1135
static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev,
					u64 snap_id)
1136
{
1137
	u32 which;
1138
	const char *snap_name;
1139

1140 1141
	which = rbd_dev_snap_index(rbd_dev, snap_id);
	if (which == BAD_SNAP_INDEX)
1142
		return ERR_PTR(-ENOENT);
1143

1144 1145
	snap_name = _rbd_dev_v1_snap_name(rbd_dev, which);
	return snap_name ? snap_name : ERR_PTR(-ENOMEM);
1146 1147 1148 1149
}

static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id)
{
1150 1151 1152
	if (snap_id == CEPH_NOSNAP)
		return RBD_SNAP_HEAD_NAME;

1153 1154 1155
	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
	if (rbd_dev->image_format == 1)
		return rbd_dev_v1_snap_name(rbd_dev, snap_id);
1156

1157
	return rbd_dev_v2_snap_name(rbd_dev, snap_id);
1158 1159
}

1160 1161
static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
				u64 *snap_size)
1162
{
1163 1164 1165 1166 1167
	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
	if (snap_id == CEPH_NOSNAP) {
		*snap_size = rbd_dev->header.image_size;
	} else if (rbd_dev->image_format == 1) {
		u32 which;
1168

1169 1170 1171
		which = rbd_dev_snap_index(rbd_dev, snap_id);
		if (which == BAD_SNAP_INDEX)
			return -ENOENT;
1172

1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184
		*snap_size = rbd_dev->header.snap_sizes[which];
	} else {
		u64 size = 0;
		int ret;

		ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size);
		if (ret)
			return ret;

		*snap_size = size;
	}
	return 0;
1185 1186
}

1187 1188
static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
			u64 *snap_features)
1189
{
1190 1191 1192 1193 1194
	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
	if (snap_id == CEPH_NOSNAP) {
		*snap_features = rbd_dev->header.features;
	} else if (rbd_dev->image_format == 1) {
		*snap_features = 0;	/* No features for format 1 */
1195
	} else {
1196 1197
		u64 features = 0;
		int ret;
1198

1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209
		ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features);
		if (ret)
			return ret;

		*snap_features = features;
	}
	return 0;
}

static int rbd_dev_mapping_set(struct rbd_device *rbd_dev)
{
1210
	u64 snap_id = rbd_dev->spec->snap_id;
1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224
	u64 size = 0;
	u64 features = 0;
	int ret;

	ret = rbd_snap_size(rbd_dev, snap_id, &size);
	if (ret)
		return ret;
	ret = rbd_snap_features(rbd_dev, snap_id, &features);
	if (ret)
		return ret;

	rbd_dev->mapping.size = size;
	rbd_dev->mapping.features = features;

1225
	return 0;
1226 1227
}

A
Alex Elder 已提交
1228 1229 1230 1231
static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev)
{
	rbd_dev->mapping.size = 0;
	rbd_dev->mapping.features = 0;
1232 1233
}

A
Alex Elder 已提交
1234 1235
static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset)
{
I
Ilya Dryomov 已提交
1236
	u64 segment_size = rbd_obj_bytes(&rbd_dev->header);
1237

A
Alex Elder 已提交
1238 1239 1240 1241 1242 1243
	return offset & (segment_size - 1);
}

static u64 rbd_segment_length(struct rbd_device *rbd_dev,
				u64 offset, u64 length)
{
I
Ilya Dryomov 已提交
1244
	u64 segment_size = rbd_obj_bytes(&rbd_dev->header);
A
Alex Elder 已提交
1245 1246 1247

	offset &= segment_size - 1;

A
Alex Elder 已提交
1248
	rbd_assert(length <= U64_MAX - offset);
A
Alex Elder 已提交
1249 1250 1251 1252
	if (offset + length > segment_size)
		length = segment_size - offset;

	return length;
1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274
}

/*
 * bio helpers
 */

static void bio_chain_put(struct bio *chain)
{
	struct bio *tmp;

	while (chain) {
		tmp = chain;
		chain = chain->bi_next;
		bio_put(tmp);
	}
}

/*
 * zeros a bio chain, starting at specific offset
 */
static void zero_bio_chain(struct bio *chain, int start_ofs)
{
1275 1276
	struct bio_vec bv;
	struct bvec_iter iter;
1277 1278 1279 1280 1281
	unsigned long flags;
	void *buf;
	int pos = 0;

	while (chain) {
1282 1283
		bio_for_each_segment(bv, chain, iter) {
			if (pos + bv.bv_len > start_ofs) {
1284
				int remainder = max(start_ofs - pos, 0);
1285
				buf = bvec_kmap_irq(&bv, &flags);
1286
				memset(buf + remainder, 0,
1287 1288
				       bv.bv_len - remainder);
				flush_dcache_page(bv.bv_page);
1289
				bvec_kunmap_irq(buf, &flags);
1290
			}
1291
			pos += bv.bv_len;
1292 1293 1294 1295 1296 1297
		}

		chain = chain->bi_next;
	}
}

A
Alex Elder 已提交
1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315
/*
 * similar to zero_bio_chain(), zeros data defined by a page array,
 * starting at the given byte offset from the start of the array and
 * continuing up to the given end offset.  The pages array is
 * assumed to be big enough to hold all bytes up to the end.
 */
static void zero_pages(struct page **pages, u64 offset, u64 end)
{
	struct page **page = &pages[offset >> PAGE_SHIFT];

	rbd_assert(end > offset);
	rbd_assert(end - offset <= (u64)SIZE_MAX);
	while (offset < end) {
		size_t page_offset;
		size_t length;
		unsigned long flags;
		void *kaddr;

1316 1317
		page_offset = offset & ~PAGE_MASK;
		length = min_t(size_t, PAGE_SIZE - page_offset, end - offset);
A
Alex Elder 已提交
1318 1319 1320
		local_irq_save(flags);
		kaddr = kmap_atomic(*page);
		memset(kaddr + page_offset, 0, length);
1321
		flush_dcache_page(*page);
A
Alex Elder 已提交
1322 1323 1324 1325 1326 1327 1328 1329
		kunmap_atomic(kaddr);
		local_irq_restore(flags);

		offset += length;
		page++;
	}
}

1330
/*
A
Alex Elder 已提交
1331 1332
 * Clone a portion of a bio, starting at the given byte offset
 * and continuing for the number of bytes indicated.
1333
 */
A
Alex Elder 已提交
1334 1335 1336 1337
static struct bio *bio_clone_range(struct bio *bio_src,
					unsigned int offset,
					unsigned int len,
					gfp_t gfpmask)
1338
{
A
Alex Elder 已提交
1339 1340
	struct bio *bio;

1341
	bio = bio_clone_fast(bio_src, gfpmask, rbd_bio_clone);
A
Alex Elder 已提交
1342 1343
	if (!bio)
		return NULL;	/* ENOMEM */
1344

K
Kent Overstreet 已提交
1345
	bio_advance(bio, offset);
1346
	bio->bi_iter.bi_size = len;
A
Alex Elder 已提交
1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376

	return bio;
}

/*
 * Clone a portion of a bio chain, starting at the given byte offset
 * into the first bio in the source chain and continuing for the
 * number of bytes indicated.  The result is another bio chain of
 * exactly the given length, or a null pointer on error.
 *
 * The bio_src and offset parameters are both in-out.  On entry they
 * refer to the first source bio and the offset into that bio where
 * the start of data to be cloned is located.
 *
 * On return, bio_src is updated to refer to the bio in the source
 * chain that contains first un-cloned byte, and *offset will
 * contain the offset of that byte within that bio.
 */
static struct bio *bio_chain_clone_range(struct bio **bio_src,
					unsigned int *offset,
					unsigned int len,
					gfp_t gfpmask)
{
	struct bio *bi = *bio_src;
	unsigned int off = *offset;
	struct bio *chain = NULL;
	struct bio **end;

	/* Build up a chain of clone bios up to the limit */

1377
	if (!bi || off >= bi->bi_iter.bi_size || !len)
A
Alex Elder 已提交
1378
		return NULL;		/* Nothing to clone */
1379

A
Alex Elder 已提交
1380 1381 1382 1383 1384
	end = &chain;
	while (len) {
		unsigned int bi_size;
		struct bio *bio;

1385 1386
		if (!bi) {
			rbd_warn(NULL, "bio_chain exhausted with %u left", len);
A
Alex Elder 已提交
1387
			goto out_err;	/* EINVAL; ran out of bio's */
1388
		}
1389
		bi_size = min_t(unsigned int, bi->bi_iter.bi_size - off, len);
A
Alex Elder 已提交
1390 1391 1392 1393 1394 1395
		bio = bio_clone_range(bi, off, bi_size, gfpmask);
		if (!bio)
			goto out_err;	/* ENOMEM */

		*end = bio;
		end = &bio->bi_next;
1396

A
Alex Elder 已提交
1397
		off += bi_size;
1398
		if (off == bi->bi_iter.bi_size) {
A
Alex Elder 已提交
1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409
			bi = bi->bi_next;
			off = 0;
		}
		len -= bi_size;
	}
	*bio_src = bi;
	*offset = off;

	return chain;
out_err:
	bio_chain_put(chain);
1410 1411 1412 1413

	return NULL;
}

1414 1415 1416 1417 1418
/*
 * The default/initial value for all object request flags is 0.  For
 * each flag, once its value is set to 1 it is never reset to 0
 * again.
 */
A
Alex Elder 已提交
1419
static void obj_request_img_data_set(struct rbd_obj_request *obj_request)
1420
{
A
Alex Elder 已提交
1421
	if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) {
1422 1423
		struct rbd_device *rbd_dev;

A
Alex Elder 已提交
1424
		rbd_dev = obj_request->img_request->rbd_dev;
1425
		rbd_warn(rbd_dev, "obj_request %p already marked img_data",
1426 1427 1428 1429
			obj_request);
	}
}

A
Alex Elder 已提交
1430
static bool obj_request_img_data_test(struct rbd_obj_request *obj_request)
1431 1432
{
	smp_mb();
A
Alex Elder 已提交
1433
	return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0;
1434 1435
}

A
Alex Elder 已提交
1436
static void obj_request_done_set(struct rbd_obj_request *obj_request)
1437
{
A
Alex Elder 已提交
1438 1439
	if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) {
		struct rbd_device *rbd_dev = NULL;
1440

A
Alex Elder 已提交
1441 1442
		if (obj_request_img_data_test(obj_request))
			rbd_dev = obj_request->img_request->rbd_dev;
1443
		rbd_warn(rbd_dev, "obj_request %p already marked done",
1444 1445 1446 1447
			obj_request);
	}
}

A
Alex Elder 已提交
1448
static bool obj_request_done_test(struct rbd_obj_request *obj_request)
1449 1450
{
	smp_mb();
A
Alex Elder 已提交
1451
	return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0;
1452 1453
}

1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484
/*
 * This sets the KNOWN flag after (possibly) setting the EXISTS
 * flag.  The latter is set based on the "exists" value provided.
 *
 * Note that for our purposes once an object exists it never goes
 * away again.  It's possible that the response from two existence
 * checks are separated by the creation of the target object, and
 * the first ("doesn't exist") response arrives *after* the second
 * ("does exist").  In that case we ignore the second one.
 */
static void obj_request_existence_set(struct rbd_obj_request *obj_request,
				bool exists)
{
	if (exists)
		set_bit(OBJ_REQ_EXISTS, &obj_request->flags);
	set_bit(OBJ_REQ_KNOWN, &obj_request->flags);
	smp_mb();
}

static bool obj_request_known_test(struct rbd_obj_request *obj_request)
{
	smp_mb();
	return test_bit(OBJ_REQ_KNOWN, &obj_request->flags) != 0;
}

static bool obj_request_exists_test(struct rbd_obj_request *obj_request)
{
	smp_mb();
	return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0;
}

1485 1486 1487 1488 1489 1490 1491 1492
static bool obj_request_overlaps_parent(struct rbd_obj_request *obj_request)
{
	struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev;

	return obj_request->img_offset <
	    round_up(rbd_dev->parent_overlap, rbd_obj_bytes(&rbd_dev->header));
}

A
Alex Elder 已提交
1493 1494
static void rbd_obj_request_get(struct rbd_obj_request *obj_request)
{
A
Alex Elder 已提交
1495
	dout("%s: obj %p (was %d)\n", __func__, obj_request,
1496
		kref_read(&obj_request->kref));
A
Alex Elder 已提交
1497 1498 1499 1500 1501 1502 1503
	kref_get(&obj_request->kref);
}

static void rbd_obj_request_destroy(struct kref *kref);
static void rbd_obj_request_put(struct rbd_obj_request *obj_request)
{
	rbd_assert(obj_request != NULL);
A
Alex Elder 已提交
1504
	dout("%s: obj %p (was %d)\n", __func__, obj_request,
1505
		kref_read(&obj_request->kref));
A
Alex Elder 已提交
1506 1507 1508
	kref_put(&obj_request->kref, rbd_obj_request_destroy);
}

1509 1510 1511
static void rbd_img_request_get(struct rbd_img_request *img_request)
{
	dout("%s: img %p (was %d)\n", __func__, img_request,
1512
	     kref_read(&img_request->kref));
1513 1514 1515
	kref_get(&img_request->kref);
}

1516 1517
static bool img_request_child_test(struct rbd_img_request *img_request);
static void rbd_parent_request_destroy(struct kref *kref);
A
Alex Elder 已提交
1518 1519 1520 1521
static void rbd_img_request_destroy(struct kref *kref);
static void rbd_img_request_put(struct rbd_img_request *img_request)
{
	rbd_assert(img_request != NULL);
A
Alex Elder 已提交
1522
	dout("%s: img %p (was %d)\n", __func__, img_request,
1523
		kref_read(&img_request->kref));
1524 1525 1526 1527
	if (img_request_child_test(img_request))
		kref_put(&img_request->kref, rbd_parent_request_destroy);
	else
		kref_put(&img_request->kref, rbd_img_request_destroy);
A
Alex Elder 已提交
1528 1529 1530 1531 1532
}

static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request,
					struct rbd_obj_request *obj_request)
{
1533 1534
	rbd_assert(obj_request->img_request == NULL);

1535
	/* Image request now owns object's original reference */
A
Alex Elder 已提交
1536
	obj_request->img_request = img_request;
1537
	obj_request->which = img_request->obj_request_count;
1538 1539
	rbd_assert(!obj_request_img_data_test(obj_request));
	obj_request_img_data_set(obj_request);
A
Alex Elder 已提交
1540
	rbd_assert(obj_request->which != BAD_WHICH);
1541 1542
	img_request->obj_request_count++;
	list_add_tail(&obj_request->links, &img_request->obj_requests);
A
Alex Elder 已提交
1543 1544
	dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
		obj_request->which);
A
Alex Elder 已提交
1545 1546 1547 1548 1549 1550
}

static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request,
					struct rbd_obj_request *obj_request)
{
	rbd_assert(obj_request->which != BAD_WHICH);
1551

A
Alex Elder 已提交
1552 1553
	dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request,
		obj_request->which);
A
Alex Elder 已提交
1554
	list_del(&obj_request->links);
1555 1556 1557 1558
	rbd_assert(img_request->obj_request_count > 0);
	img_request->obj_request_count--;
	rbd_assert(obj_request->which == img_request->obj_request_count);
	obj_request->which = BAD_WHICH;
1559
	rbd_assert(obj_request_img_data_test(obj_request));
A
Alex Elder 已提交
1560 1561
	rbd_assert(obj_request->img_request == img_request);
	obj_request->img_request = NULL;
1562
	obj_request->callback = NULL;
A
Alex Elder 已提交
1563 1564 1565 1566 1567 1568
	rbd_obj_request_put(obj_request);
}

static bool obj_request_type_valid(enum obj_request_type type)
{
	switch (type) {
1569
	case OBJ_REQUEST_NODATA:
A
Alex Elder 已提交
1570
	case OBJ_REQUEST_BIO:
1571
	case OBJ_REQUEST_PAGES:
A
Alex Elder 已提交
1572 1573 1574 1575 1576 1577
		return true;
	default:
		return false;
	}
}

1578 1579
static void rbd_img_obj_callback(struct rbd_obj_request *obj_request);

1580
static void rbd_obj_request_submit(struct rbd_obj_request *obj_request)
A
Alex Elder 已提交
1581
{
1582 1583
	struct ceph_osd_request *osd_req = obj_request->osd_req;

1584 1585
	dout("%s %p object_no %016llx %llu~%llu osd_req %p\n", __func__,
	     obj_request, obj_request->object_no, obj_request->offset,
1586
	     obj_request->length, osd_req);
1587 1588 1589 1590
	if (obj_request_img_data_test(obj_request)) {
		WARN_ON(obj_request->callback != rbd_img_obj_callback);
		rbd_img_request_get(obj_request->img_request);
	}
1591
	ceph_osdc_start_request(osd_req->r_osdc, osd_req, false);
A
Alex Elder 已提交
1592 1593 1594 1595
}

static void rbd_img_request_complete(struct rbd_img_request *img_request)
{
1596

A
Alex Elder 已提交
1597
	dout("%s: img %p\n", __func__, img_request);
1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613

	/*
	 * If no error occurred, compute the aggregate transfer
	 * count for the image request.  We could instead use
	 * atomic64_cmpxchg() to update it as each object request
	 * completes; not clear which way is better off hand.
	 */
	if (!img_request->result) {
		struct rbd_obj_request *obj_request;
		u64 xferred = 0;

		for_each_obj_request(img_request, obj_request)
			xferred += obj_request->xferred;
		img_request->xferred = xferred;
	}

A
Alex Elder 已提交
1614 1615 1616 1617 1618 1619
	if (img_request->callback)
		img_request->callback(img_request);
	else
		rbd_img_request_put(img_request);
}

A
Alex Elder 已提交
1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636
/*
 * The default/initial value for all image request flags is 0.  Each
 * is conditionally set to 1 at image request initialization time
 * and currently never change thereafter.
 */
static void img_request_write_set(struct rbd_img_request *img_request)
{
	set_bit(IMG_REQ_WRITE, &img_request->flags);
	smp_mb();
}

static bool img_request_write_test(struct rbd_img_request *img_request)
{
	smp_mb();
	return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0;
}

1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651
/*
 * Set the discard flag when the img_request is an discard request
 */
static void img_request_discard_set(struct rbd_img_request *img_request)
{
	set_bit(IMG_REQ_DISCARD, &img_request->flags);
	smp_mb();
}

static bool img_request_discard_test(struct rbd_img_request *img_request)
{
	smp_mb();
	return test_bit(IMG_REQ_DISCARD, &img_request->flags) != 0;
}

1652 1653 1654 1655 1656 1657
static void img_request_child_set(struct rbd_img_request *img_request)
{
	set_bit(IMG_REQ_CHILD, &img_request->flags);
	smp_mb();
}

1658 1659 1660 1661 1662 1663
static void img_request_child_clear(struct rbd_img_request *img_request)
{
	clear_bit(IMG_REQ_CHILD, &img_request->flags);
	smp_mb();
}

1664 1665 1666 1667 1668 1669
static bool img_request_child_test(struct rbd_img_request *img_request)
{
	smp_mb();
	return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0;
}

1670 1671 1672 1673 1674 1675
static void img_request_layered_set(struct rbd_img_request *img_request)
{
	set_bit(IMG_REQ_LAYERED, &img_request->flags);
	smp_mb();
}

1676 1677 1678 1679 1680 1681
static void img_request_layered_clear(struct rbd_img_request *img_request)
{
	clear_bit(IMG_REQ_LAYERED, &img_request->flags);
	smp_mb();
}

1682 1683 1684 1685 1686 1687
static bool img_request_layered_test(struct rbd_img_request *img_request)
{
	smp_mb();
	return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0;
}

1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698
static enum obj_operation_type
rbd_img_request_op_type(struct rbd_img_request *img_request)
{
	if (img_request_write_test(img_request))
		return OBJ_OP_WRITE;
	else if (img_request_discard_test(img_request))
		return OBJ_OP_DISCARD;
	else
		return OBJ_OP_READ;
}

1699 1700 1701
static void
rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request)
{
A
Alex Elder 已提交
1702 1703 1704
	u64 xferred = obj_request->xferred;
	u64 length = obj_request->length;

1705 1706
	dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
		obj_request, obj_request->img_request, obj_request->result,
A
Alex Elder 已提交
1707
		xferred, length);
1708
	/*
1709 1710 1711 1712 1713 1714
	 * ENOENT means a hole in the image.  We zero-fill the entire
	 * length of the request.  A short read also implies zero-fill
	 * to the end of the request.  An error requires the whole
	 * length of the request to be reported finished with an error
	 * to the block layer.  In each case we update the xferred
	 * count to indicate the whole request was satisfied.
1715
	 */
A
Alex Elder 已提交
1716
	rbd_assert(obj_request->type != OBJ_REQUEST_NODATA);
1717
	if (obj_request->result == -ENOENT) {
A
Alex Elder 已提交
1718 1719 1720 1721
		if (obj_request->type == OBJ_REQUEST_BIO)
			zero_bio_chain(obj_request->bio_list, 0);
		else
			zero_pages(obj_request->pages, 0, length);
1722
		obj_request->result = 0;
A
Alex Elder 已提交
1723 1724 1725 1726 1727
	} else if (xferred < length && !obj_request->result) {
		if (obj_request->type == OBJ_REQUEST_BIO)
			zero_bio_chain(obj_request->bio_list, xferred);
		else
			zero_pages(obj_request->pages, xferred, length);
1728
	}
1729
	obj_request->xferred = length;
1730 1731 1732
	obj_request_done_set(obj_request);
}

A
Alex Elder 已提交
1733 1734
static void rbd_obj_request_complete(struct rbd_obj_request *obj_request)
{
A
Alex Elder 已提交
1735 1736
	dout("%s: obj %p cb %p\n", __func__, obj_request,
		obj_request->callback);
A
Alex Elder 已提交
1737 1738
	if (obj_request->callback)
		obj_request->callback(obj_request);
1739 1740
	else
		complete_all(&obj_request->completion);
A
Alex Elder 已提交
1741 1742
}

1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758
static void rbd_obj_request_error(struct rbd_obj_request *obj_request, int err)
{
	obj_request->result = err;
	obj_request->xferred = 0;
	/*
	 * kludge - mirror rbd_obj_request_submit() to match a put in
	 * rbd_img_obj_callback()
	 */
	if (obj_request_img_data_test(obj_request)) {
		WARN_ON(obj_request->callback != rbd_img_obj_callback);
		rbd_img_request_get(obj_request->img_request);
	}
	obj_request_done_set(obj_request);
	rbd_obj_request_complete(obj_request);
}

1759
static void rbd_osd_read_callback(struct rbd_obj_request *obj_request)
A
Alex Elder 已提交
1760
{
A
Alex Elder 已提交
1761
	struct rbd_img_request *img_request = NULL;
A
Alex Elder 已提交
1762
	struct rbd_device *rbd_dev = NULL;
A
Alex Elder 已提交
1763 1764 1765 1766 1767
	bool layered = false;

	if (obj_request_img_data_test(obj_request)) {
		img_request = obj_request->img_request;
		layered = img_request && img_request_layered_test(img_request);
A
Alex Elder 已提交
1768
		rbd_dev = img_request->rbd_dev;
A
Alex Elder 已提交
1769
	}
A
Alex Elder 已提交
1770 1771 1772 1773

	dout("%s: obj %p img %p result %d %llu/%llu\n", __func__,
		obj_request, img_request, obj_request->result,
		obj_request->xferred, obj_request->length);
A
Alex Elder 已提交
1774 1775
	if (layered && obj_request->result == -ENOENT &&
			obj_request->img_offset < rbd_dev->parent_overlap)
A
Alex Elder 已提交
1776 1777
		rbd_img_parent_read(obj_request);
	else if (img_request)
1778 1779 1780
		rbd_img_obj_request_read_callback(obj_request);
	else
		obj_request_done_set(obj_request);
A
Alex Elder 已提交
1781 1782
}

1783
static void rbd_osd_write_callback(struct rbd_obj_request *obj_request)
A
Alex Elder 已提交
1784
{
1785 1786 1787
	dout("%s: obj %p result %d %llu\n", __func__, obj_request,
		obj_request->result, obj_request->length);
	/*
A
Alex Elder 已提交
1788 1789
	 * There is no such thing as a successful short write.  Set
	 * it to our originally-requested length.
1790 1791
	 */
	obj_request->xferred = obj_request->length;
1792
	obj_request_done_set(obj_request);
A
Alex Elder 已提交
1793 1794
}

1795 1796 1797 1798 1799 1800 1801 1802 1803
static void rbd_osd_discard_callback(struct rbd_obj_request *obj_request)
{
	dout("%s: obj %p result %d %llu\n", __func__, obj_request,
		obj_request->result, obj_request->length);
	/*
	 * There is no such thing as a successful short discard.  Set
	 * it to our originally-requested length.
	 */
	obj_request->xferred = obj_request->length;
1804 1805 1806
	/* discarding a non-existent object is not a problem */
	if (obj_request->result == -ENOENT)
		obj_request->result = 0;
1807 1808 1809
	obj_request_done_set(obj_request);
}

A
Alex Elder 已提交
1810 1811 1812 1813
/*
 * For a simple stat call there's nothing to do.  We'll do more if
 * this is part of a write sequence for a layered image.
 */
1814
static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request)
A
Alex Elder 已提交
1815
{
A
Alex Elder 已提交
1816
	dout("%s: obj %p\n", __func__, obj_request);
A
Alex Elder 已提交
1817 1818 1819
	obj_request_done_set(obj_request);
}

I
Ilya Dryomov 已提交
1820 1821 1822 1823 1824 1825 1826 1827 1828 1829
static void rbd_osd_call_callback(struct rbd_obj_request *obj_request)
{
	dout("%s: obj %p\n", __func__, obj_request);

	if (obj_request_img_data_test(obj_request))
		rbd_osd_copyup_callback(obj_request);
	else
		obj_request_done_set(obj_request);
}

1830
static void rbd_osd_req_callback(struct ceph_osd_request *osd_req)
A
Alex Elder 已提交
1831 1832 1833 1834
{
	struct rbd_obj_request *obj_request = osd_req->r_priv;
	u16 opcode;

1835
	dout("%s: osd_req %p\n", __func__, osd_req);
A
Alex Elder 已提交
1836
	rbd_assert(osd_req == obj_request->osd_req);
A
Alex Elder 已提交
1837 1838 1839 1840 1841 1842
	if (obj_request_img_data_test(obj_request)) {
		rbd_assert(obj_request->img_request);
		rbd_assert(obj_request->which != BAD_WHICH);
	} else {
		rbd_assert(obj_request->which == BAD_WHICH);
	}
A
Alex Elder 已提交
1843

1844 1845
	if (osd_req->r_result < 0)
		obj_request->result = osd_req->r_result;
A
Alex Elder 已提交
1846

1847 1848
	/*
	 * We support a 64-bit length, but ultimately it has to be
C
Christoph Hellwig 已提交
1849 1850
	 * passed to the block layer, which just supports a 32-bit
	 * length field.
1851
	 */
1852
	obj_request->xferred = osd_req->r_ops[0].outdata_len;
A
Alex Elder 已提交
1853
	rbd_assert(obj_request->xferred < (u64)UINT_MAX);
1854

1855
	opcode = osd_req->r_ops[0].op;
A
Alex Elder 已提交
1856 1857
	switch (opcode) {
	case CEPH_OSD_OP_READ:
1858
		rbd_osd_read_callback(obj_request);
A
Alex Elder 已提交
1859
		break;
1860
	case CEPH_OSD_OP_SETALLOCHINT:
1861 1862
		rbd_assert(osd_req->r_ops[1].op == CEPH_OSD_OP_WRITE ||
			   osd_req->r_ops[1].op == CEPH_OSD_OP_WRITEFULL);
1863
		/* fall through */
A
Alex Elder 已提交
1864
	case CEPH_OSD_OP_WRITE:
1865
	case CEPH_OSD_OP_WRITEFULL:
1866
		rbd_osd_write_callback(obj_request);
A
Alex Elder 已提交
1867
		break;
A
Alex Elder 已提交
1868
	case CEPH_OSD_OP_STAT:
1869
		rbd_osd_stat_callback(obj_request);
A
Alex Elder 已提交
1870
		break;
1871 1872 1873 1874 1875
	case CEPH_OSD_OP_DELETE:
	case CEPH_OSD_OP_TRUNCATE:
	case CEPH_OSD_OP_ZERO:
		rbd_osd_discard_callback(obj_request);
		break;
1876
	case CEPH_OSD_OP_CALL:
I
Ilya Dryomov 已提交
1877 1878
		rbd_osd_call_callback(obj_request);
		break;
A
Alex Elder 已提交
1879
	default:
1880 1881
		rbd_warn(NULL, "unexpected OSD op: object_no %016llx opcode %d",
			 obj_request->object_no, opcode);
A
Alex Elder 已提交
1882 1883 1884
		break;
	}

1885
	if (obj_request_done_test(obj_request))
A
Alex Elder 已提交
1886 1887 1888
		rbd_obj_request_complete(obj_request);
}

1889
static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request)
A
Alex Elder 已提交
1890
{
1891
	struct ceph_osd_request *osd_req = obj_request->osd_req;
A
Alex Elder 已提交
1892

1893 1894
	rbd_assert(obj_request_img_data_test(obj_request));
	osd_req->r_snapid = obj_request->img_request->snap_id;
1895 1896 1897 1898 1899 1900
}

static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request)
{
	struct ceph_osd_request *osd_req = obj_request->osd_req;

1901
	ktime_get_real_ts(&osd_req->r_mtime);
1902
	osd_req->r_data_offset = obj_request->offset;
A
Alex Elder 已提交
1903 1904
}

1905 1906 1907 1908 1909 1910 1911 1912
static struct ceph_osd_request *
__rbd_osd_req_create(struct rbd_device *rbd_dev,
		     struct ceph_snap_context *snapc,
		     int num_ops, unsigned int flags,
		     struct rbd_obj_request *obj_request)
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	struct ceph_osd_request *req;
1913 1914
	const char *name_format = rbd_dev->image_format == 1 ?
				      RBD_V1_DATA_FORMAT : RBD_V2_DATA_FORMAT;
1915 1916 1917 1918 1919 1920 1921 1922 1923 1924

	req = ceph_osdc_alloc_request(osdc, snapc, num_ops, false, GFP_NOIO);
	if (!req)
		return NULL;

	req->r_flags = flags;
	req->r_callback = rbd_osd_req_callback;
	req->r_priv = obj_request;

	req->r_base_oloc.pool = rbd_dev->layout.pool_id;
1925 1926
	if (ceph_oid_aprintf(&req->r_base_oid, GFP_NOIO, name_format,
			rbd_dev->header.object_prefix, obj_request->object_no))
1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938
		goto err_req;

	if (ceph_osdc_alloc_messages(req, GFP_NOIO))
		goto err_req;

	return req;

err_req:
	ceph_osdc_put_request(req);
	return NULL;
}

1939 1940 1941 1942 1943 1944
/*
 * Create an osd request.  A read request has one osd op (read).
 * A write request has either one (watch) or two (hint+write) osd ops.
 * (All rbd data writes are prefixed with an allocation hint op, but
 * technically osd watch is a write request, hence this distinction.)
 */
A
Alex Elder 已提交
1945 1946
static struct ceph_osd_request *rbd_osd_req_create(
					struct rbd_device *rbd_dev,
G
Guangliang Zhao 已提交
1947
					enum obj_operation_type op_type,
1948
					unsigned int num_ops,
A
Alex Elder 已提交
1949
					struct rbd_obj_request *obj_request)
A
Alex Elder 已提交
1950 1951 1952
{
	struct ceph_snap_context *snapc = NULL;

1953 1954
	if (obj_request_img_data_test(obj_request) &&
		(op_type == OBJ_OP_DISCARD || op_type == OBJ_OP_WRITE)) {
1955
		struct rbd_img_request *img_request = obj_request->img_request;
1956 1957 1958 1959 1960
		if (op_type == OBJ_OP_WRITE) {
			rbd_assert(img_request_write_test(img_request));
		} else {
			rbd_assert(img_request_discard_test(img_request));
		}
G
Guangliang Zhao 已提交
1961
		snapc = img_request->snapc;
A
Alex Elder 已提交
1962 1963
	}

G
Guangliang Zhao 已提交
1964
	rbd_assert(num_ops == 1 || ((op_type == OBJ_OP_WRITE) && num_ops == 2));
1965

1966 1967
	return __rbd_osd_req_create(rbd_dev, snapc, num_ops,
	    (op_type == OBJ_OP_WRITE || op_type == OBJ_OP_DISCARD) ?
1968
	    CEPH_OSD_FLAG_WRITE : CEPH_OSD_FLAG_READ, obj_request);
A
Alex Elder 已提交
1969 1970
}

1971
/*
1972 1973 1974 1975
 * Create a copyup osd request based on the information in the object
 * request supplied.  A copyup request has two or three osd ops, a
 * copyup method call, potentially a hint op, and a write or truncate
 * or zero op.
1976 1977 1978 1979 1980
 */
static struct ceph_osd_request *
rbd_osd_req_create_copyup(struct rbd_obj_request *obj_request)
{
	struct rbd_img_request *img_request;
1981
	int num_osd_ops = 3;
1982 1983 1984 1985

	rbd_assert(obj_request_img_data_test(obj_request));
	img_request = obj_request->img_request;
	rbd_assert(img_request);
1986 1987
	rbd_assert(img_request_write_test(img_request) ||
			img_request_discard_test(img_request));
1988

1989 1990 1991
	if (img_request_discard_test(img_request))
		num_osd_ops = 2;

1992 1993
	return __rbd_osd_req_create(img_request->rbd_dev,
				    img_request->snapc, num_osd_ops,
1994
				    CEPH_OSD_FLAG_WRITE, obj_request);
1995 1996
}

A
Alex Elder 已提交
1997 1998 1999 2000 2001
static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req)
{
	ceph_osdc_put_request(osd_req);
}

2002 2003
static struct rbd_obj_request *
rbd_obj_request_create(enum obj_request_type type)
A
Alex Elder 已提交
2004 2005 2006 2007 2008
{
	struct rbd_obj_request *obj_request;

	rbd_assert(obj_request_type_valid(type));

2009
	obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_NOIO);
2010
	if (!obj_request)
2011 2012
		return NULL;

A
Alex Elder 已提交
2013 2014 2015
	obj_request->which = BAD_WHICH;
	obj_request->type = type;
	INIT_LIST_HEAD(&obj_request->links);
2016
	init_completion(&obj_request->completion);
A
Alex Elder 已提交
2017 2018
	kref_init(&obj_request->kref);

2019
	dout("%s %p\n", __func__, obj_request);
A
Alex Elder 已提交
2020 2021 2022 2023 2024 2025 2026 2027 2028
	return obj_request;
}

static void rbd_obj_request_destroy(struct kref *kref)
{
	struct rbd_obj_request *obj_request;

	obj_request = container_of(kref, struct rbd_obj_request, kref);

A
Alex Elder 已提交
2029 2030
	dout("%s: obj %p\n", __func__, obj_request);

A
Alex Elder 已提交
2031 2032 2033 2034 2035 2036 2037 2038
	rbd_assert(obj_request->img_request == NULL);
	rbd_assert(obj_request->which == BAD_WHICH);

	if (obj_request->osd_req)
		rbd_osd_req_destroy(obj_request->osd_req);

	rbd_assert(obj_request_type_valid(obj_request->type));
	switch (obj_request->type) {
2039 2040
	case OBJ_REQUEST_NODATA:
		break;		/* Nothing to do */
A
Alex Elder 已提交
2041 2042 2043 2044
	case OBJ_REQUEST_BIO:
		if (obj_request->bio_list)
			bio_chain_put(obj_request->bio_list);
		break;
2045
	case OBJ_REQUEST_PAGES:
2046 2047 2048
		/* img_data requests don't own their page array */
		if (obj_request->pages &&
		    !obj_request_img_data_test(obj_request))
2049 2050 2051
			ceph_release_page_vector(obj_request->pages,
						obj_request->page_count);
		break;
A
Alex Elder 已提交
2052 2053
	}

2054
	kmem_cache_free(rbd_obj_request_cache, obj_request);
A
Alex Elder 已提交
2055 2056
}

A
Alex Elder 已提交
2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067
/* It's OK to call this for a device with no parent */

static void rbd_spec_put(struct rbd_spec *spec);
static void rbd_dev_unparent(struct rbd_device *rbd_dev)
{
	rbd_dev_remove_parent(rbd_dev);
	rbd_spec_put(rbd_dev->parent_spec);
	rbd_dev->parent_spec = NULL;
	rbd_dev->parent_overlap = 0;
}

2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089
/*
 * Parent image reference counting is used to determine when an
 * image's parent fields can be safely torn down--after there are no
 * more in-flight requests to the parent image.  When the last
 * reference is dropped, cleaning them up is safe.
 */
static void rbd_dev_parent_put(struct rbd_device *rbd_dev)
{
	int counter;

	if (!rbd_dev->parent_spec)
		return;

	counter = atomic_dec_return_safe(&rbd_dev->parent_ref);
	if (counter > 0)
		return;

	/* Last reference; clean up parent data structures */

	if (!counter)
		rbd_dev_unparent(rbd_dev);
	else
2090
		rbd_warn(rbd_dev, "parent reference underflow");
2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102
}

/*
 * If an image has a non-zero parent overlap, get a reference to its
 * parent.
 *
 * Returns true if the rbd device has a parent with a non-zero
 * overlap and a reference for it was successfully taken, or
 * false otherwise.
 */
static bool rbd_dev_parent_get(struct rbd_device *rbd_dev)
{
2103
	int counter = 0;
2104 2105 2106 2107

	if (!rbd_dev->parent_spec)
		return false;

2108 2109 2110 2111
	down_read(&rbd_dev->header_rwsem);
	if (rbd_dev->parent_overlap)
		counter = atomic_inc_return_safe(&rbd_dev->parent_ref);
	up_read(&rbd_dev->header_rwsem);
2112 2113

	if (counter < 0)
2114
		rbd_warn(rbd_dev, "parent reference overflow");
2115

2116
	return counter > 0;
2117 2118
}

A
Alex Elder 已提交
2119 2120 2121 2122 2123
/*
 * Caller is responsible for filling in the list of object requests
 * that comprises the image request, and the Linux request pointer
 * (if there is one).
 */
A
Alex Elder 已提交
2124 2125
static struct rbd_img_request *rbd_img_request_create(
					struct rbd_device *rbd_dev,
A
Alex Elder 已提交
2126
					u64 offset, u64 length,
G
Guangliang Zhao 已提交
2127
					enum obj_operation_type op_type,
2128
					struct ceph_snap_context *snapc)
A
Alex Elder 已提交
2129 2130 2131
{
	struct rbd_img_request *img_request;

2132
	img_request = kmem_cache_alloc(rbd_img_request_cache, GFP_NOIO);
A
Alex Elder 已提交
2133 2134 2135 2136 2137 2138 2139
	if (!img_request)
		return NULL;

	img_request->rq = NULL;
	img_request->rbd_dev = rbd_dev;
	img_request->offset = offset;
	img_request->length = length;
A
Alex Elder 已提交
2140
	img_request->flags = 0;
2141 2142 2143 2144
	if (op_type == OBJ_OP_DISCARD) {
		img_request_discard_set(img_request);
		img_request->snapc = snapc;
	} else if (op_type == OBJ_OP_WRITE) {
A
Alex Elder 已提交
2145
		img_request_write_set(img_request);
2146
		img_request->snapc = snapc;
A
Alex Elder 已提交
2147
	} else {
A
Alex Elder 已提交
2148
		img_request->snap_id = rbd_dev->spec->snap_id;
A
Alex Elder 已提交
2149
	}
2150
	if (rbd_dev_parent_get(rbd_dev))
2151
		img_request_layered_set(img_request);
A
Alex Elder 已提交
2152 2153 2154
	spin_lock_init(&img_request->completion_lock);
	img_request->next_completion = 0;
	img_request->callback = NULL;
2155
	img_request->result = 0;
A
Alex Elder 已提交
2156 2157 2158 2159
	img_request->obj_request_count = 0;
	INIT_LIST_HEAD(&img_request->obj_requests);
	kref_init(&img_request->kref);

A
Alex Elder 已提交
2160
	dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev,
G
Guangliang Zhao 已提交
2161
		obj_op_name(op_type), offset, length, img_request);
A
Alex Elder 已提交
2162

A
Alex Elder 已提交
2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173
	return img_request;
}

static void rbd_img_request_destroy(struct kref *kref)
{
	struct rbd_img_request *img_request;
	struct rbd_obj_request *obj_request;
	struct rbd_obj_request *next_obj_request;

	img_request = container_of(kref, struct rbd_img_request, kref);

A
Alex Elder 已提交
2174 2175
	dout("%s: img %p\n", __func__, img_request);

A
Alex Elder 已提交
2176 2177
	for_each_obj_request_safe(img_request, obj_request, next_obj_request)
		rbd_img_obj_request_del(img_request, obj_request);
2178
	rbd_assert(img_request->obj_request_count == 0);
A
Alex Elder 已提交
2179

2180 2181 2182 2183 2184
	if (img_request_layered_test(img_request)) {
		img_request_layered_clear(img_request);
		rbd_dev_parent_put(img_request->rbd_dev);
	}

2185 2186
	if (img_request_write_test(img_request) ||
		img_request_discard_test(img_request))
2187
		ceph_put_snap_context(img_request->snapc);
A
Alex Elder 已提交
2188

2189
	kmem_cache_free(rbd_img_request_cache, img_request);
A
Alex Elder 已提交
2190 2191
}

2192 2193 2194 2195 2196 2197 2198 2199 2200 2201
static struct rbd_img_request *rbd_parent_request_create(
					struct rbd_obj_request *obj_request,
					u64 img_offset, u64 length)
{
	struct rbd_img_request *parent_request;
	struct rbd_device *rbd_dev;

	rbd_assert(obj_request->img_request);
	rbd_dev = obj_request->img_request->rbd_dev;

2202
	parent_request = rbd_img_request_create(rbd_dev->parent, img_offset,
G
Guangliang Zhao 已提交
2203
						length, OBJ_OP_READ, NULL);
2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228
	if (!parent_request)
		return NULL;

	img_request_child_set(parent_request);
	rbd_obj_request_get(obj_request);
	parent_request->obj_request = obj_request;

	return parent_request;
}

static void rbd_parent_request_destroy(struct kref *kref)
{
	struct rbd_img_request *parent_request;
	struct rbd_obj_request *orig_request;

	parent_request = container_of(kref, struct rbd_img_request, kref);
	orig_request = parent_request->obj_request;

	parent_request->obj_request = NULL;
	rbd_obj_request_put(orig_request);
	img_request_child_clear(parent_request);

	rbd_img_request_destroy(kref);
}

2229 2230
static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request)
{
2231
	struct rbd_img_request *img_request;
2232 2233
	unsigned int xferred;
	int result;
A
Alex Elder 已提交
2234
	bool more;
2235

2236 2237 2238
	rbd_assert(obj_request_img_data_test(obj_request));
	img_request = obj_request->img_request;

2239 2240 2241 2242 2243
	rbd_assert(obj_request->xferred <= (u64)UINT_MAX);
	xferred = (unsigned int)obj_request->xferred;
	result = obj_request->result;
	if (result) {
		struct rbd_device *rbd_dev = img_request->rbd_dev;
G
Guangliang Zhao 已提交
2244 2245
		enum obj_operation_type op_type;

2246 2247 2248 2249 2250 2251
		if (img_request_discard_test(img_request))
			op_type = OBJ_OP_DISCARD;
		else if (img_request_write_test(img_request))
			op_type = OBJ_OP_WRITE;
		else
			op_type = OBJ_OP_READ;
2252

2253
		rbd_warn(rbd_dev, "%s %llx at %llx (%llx)",
G
Guangliang Zhao 已提交
2254 2255
			obj_op_name(op_type), obj_request->length,
			obj_request->img_offset, obj_request->offset);
2256
		rbd_warn(rbd_dev, "  result %d xferred %x",
2257 2258 2259
			result, xferred);
		if (!img_request->result)
			img_request->result = result;
2260 2261 2262 2263 2264
		/*
		 * Need to end I/O on the entire obj_request worth of
		 * bytes in case of error.
		 */
		xferred = obj_request->length;
2265 2266
	}

A
Alex Elder 已提交
2267 2268 2269 2270
	if (img_request_child_test(img_request)) {
		rbd_assert(img_request->obj_request != NULL);
		more = obj_request->which < img_request->obj_request_count - 1;
	} else {
2271 2272
		blk_status_t status = errno_to_blk_status(result);

A
Alex Elder 已提交
2273
		rbd_assert(img_request->rq != NULL);
C
Christoph Hellwig 已提交
2274

2275
		more = blk_update_request(img_request->rq, status, xferred);
C
Christoph Hellwig 已提交
2276
		if (!more)
2277
			__blk_mq_end_request(img_request->rq, status);
A
Alex Elder 已提交
2278 2279 2280
	}

	return more;
2281 2282
}

2283 2284 2285 2286 2287 2288
static void rbd_img_obj_callback(struct rbd_obj_request *obj_request)
{
	struct rbd_img_request *img_request;
	u32 which = obj_request->which;
	bool more = true;

2289
	rbd_assert(obj_request_img_data_test(obj_request));
2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307
	img_request = obj_request->img_request;

	dout("%s: img %p obj %p\n", __func__, img_request, obj_request);
	rbd_assert(img_request != NULL);
	rbd_assert(img_request->obj_request_count > 0);
	rbd_assert(which != BAD_WHICH);
	rbd_assert(which < img_request->obj_request_count);

	spin_lock_irq(&img_request->completion_lock);
	if (which != img_request->next_completion)
		goto out;

	for_each_obj_request_from(img_request, obj_request) {
		rbd_assert(more);
		rbd_assert(which < img_request->obj_request_count);

		if (!obj_request_done_test(obj_request))
			break;
2308
		more = rbd_img_obj_end_request(obj_request);
2309 2310 2311 2312 2313 2314 2315
		which++;
	}

	rbd_assert(more ^ (which == img_request->obj_request_count));
	img_request->next_completion = which;
out:
	spin_unlock_irq(&img_request->completion_lock);
2316
	rbd_img_request_put(img_request);
2317 2318 2319 2320 2321

	if (!more)
		rbd_img_request_complete(img_request);
}

2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340
/*
 * Add individual osd ops to the given ceph_osd_request and prepare
 * them for submission. num_ops is the current number of
 * osd operations already to the object request.
 */
static void rbd_img_obj_request_fill(struct rbd_obj_request *obj_request,
				struct ceph_osd_request *osd_request,
				enum obj_operation_type op_type,
				unsigned int num_ops)
{
	struct rbd_img_request *img_request = obj_request->img_request;
	struct rbd_device *rbd_dev = img_request->rbd_dev;
	u64 object_size = rbd_obj_bytes(&rbd_dev->header);
	u64 offset = obj_request->offset;
	u64 length = obj_request->length;
	u64 img_end;
	u16 opcode;

	if (op_type == OBJ_OP_DISCARD) {
2341 2342 2343
		if (!offset && length == object_size &&
		    (!img_request_layered_test(img_request) ||
		     !obj_request_overlaps_parent(obj_request))) {
2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357
			opcode = CEPH_OSD_OP_DELETE;
		} else if ((offset + length == object_size)) {
			opcode = CEPH_OSD_OP_TRUNCATE;
		} else {
			down_read(&rbd_dev->header_rwsem);
			img_end = rbd_dev->header.image_size;
			up_read(&rbd_dev->header_rwsem);

			if (obj_request->img_offset + length == img_end)
				opcode = CEPH_OSD_OP_TRUNCATE;
			else
				opcode = CEPH_OSD_OP_ZERO;
		}
	} else if (op_type == OBJ_OP_WRITE) {
2358 2359 2360 2361
		if (!offset && length == object_size)
			opcode = CEPH_OSD_OP_WRITEFULL;
		else
			opcode = CEPH_OSD_OP_WRITE;
2362 2363 2364 2365 2366 2367 2368
		osd_req_op_alloc_hint_init(osd_request, num_ops,
					object_size, object_size);
		num_ops++;
	} else {
		opcode = CEPH_OSD_OP_READ;
	}

2369
	if (opcode == CEPH_OSD_OP_DELETE)
2370
		osd_req_op_init(osd_request, num_ops, opcode, 0);
2371 2372 2373 2374
	else
		osd_req_op_extent_init(osd_request, num_ops, opcode,
				       offset, length, 0, 0);

2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389
	if (obj_request->type == OBJ_REQUEST_BIO)
		osd_req_op_extent_osd_data_bio(osd_request, num_ops,
					obj_request->bio_list, length);
	else if (obj_request->type == OBJ_REQUEST_PAGES)
		osd_req_op_extent_osd_data_pages(osd_request, num_ops,
					obj_request->pages, length,
					offset & ~PAGE_MASK, false, false);

	/* Discards are also writes */
	if (op_type == OBJ_OP_WRITE || op_type == OBJ_OP_DISCARD)
		rbd_osd_req_format_write(obj_request);
	else
		rbd_osd_req_format_read(obj_request);
}

2390 2391 2392 2393 2394 2395 2396 2397 2398 2399 2400
/*
 * Split up an image request into one or more object requests, each
 * to a different object.  The "type" parameter indicates whether
 * "data_desc" is the pointer to the head of a list of bio
 * structures, or the base of a page array.  In either case this
 * function assumes data_desc describes memory sufficient to hold
 * all data described by the image request.
 */
static int rbd_img_request_fill(struct rbd_img_request *img_request,
					enum obj_request_type type,
					void *data_desc)
A
Alex Elder 已提交
2401 2402 2403 2404
{
	struct rbd_device *rbd_dev = img_request->rbd_dev;
	struct rbd_obj_request *obj_request = NULL;
	struct rbd_obj_request *next_obj_request;
J
Jingoo Han 已提交
2405
	struct bio *bio_list = NULL;
2406
	unsigned int bio_offset = 0;
J
Jingoo Han 已提交
2407
	struct page **pages = NULL;
G
Guangliang Zhao 已提交
2408
	enum obj_operation_type op_type;
2409
	u64 img_offset;
A
Alex Elder 已提交
2410 2411
	u64 resid;

2412 2413
	dout("%s: img %p type %d data_desc %p\n", __func__, img_request,
		(int)type, data_desc);
A
Alex Elder 已提交
2414

2415
	img_offset = img_request->offset;
A
Alex Elder 已提交
2416
	resid = img_request->length;
A
Alex Elder 已提交
2417
	rbd_assert(resid > 0);
2418
	op_type = rbd_img_request_op_type(img_request);
2419 2420 2421

	if (type == OBJ_REQUEST_BIO) {
		bio_list = data_desc;
2422 2423
		rbd_assert(img_offset ==
			   bio_list->bi_iter.bi_sector << SECTOR_SHIFT);
2424
	} else if (type == OBJ_REQUEST_PAGES) {
2425 2426 2427
		pages = data_desc;
	}

A
Alex Elder 已提交
2428
	while (resid) {
2429
		struct ceph_osd_request *osd_req;
2430
		u64 object_no = img_offset >> rbd_dev->header.obj_order;
2431 2432
		u64 offset = rbd_segment_offset(rbd_dev, img_offset);
		u64 length = rbd_segment_length(rbd_dev, img_offset, resid);
A
Alex Elder 已提交
2433

2434
		obj_request = rbd_obj_request_create(type);
A
Alex Elder 已提交
2435 2436
		if (!obj_request)
			goto out_unwind;
2437

2438
		obj_request->object_no = object_no;
2439 2440 2441
		obj_request->offset = offset;
		obj_request->length = length;

2442 2443 2444 2445 2446
		/*
		 * set obj_request->img_request before creating the
		 * osd_request so that it gets the right snapc
		 */
		rbd_img_obj_request_add(img_request, obj_request);
A
Alex Elder 已提交
2447

2448 2449 2450 2451 2452 2453 2454 2455 2456
		if (type == OBJ_REQUEST_BIO) {
			unsigned int clone_size;

			rbd_assert(length <= (u64)UINT_MAX);
			clone_size = (unsigned int)length;
			obj_request->bio_list =
					bio_chain_clone_range(&bio_list,
								&bio_offset,
								clone_size,
2457
								GFP_NOIO);
2458
			if (!obj_request->bio_list)
2459
				goto out_unwind;
2460
		} else if (type == OBJ_REQUEST_PAGES) {
2461 2462 2463 2464 2465 2466 2467 2468 2469
			unsigned int page_count;

			obj_request->pages = pages;
			page_count = (u32)calc_pages_for(offset, length);
			obj_request->page_count = page_count;
			if ((offset + length) & ~PAGE_MASK)
				page_count--;	/* more on last page */
			pages += page_count;
		}
A
Alex Elder 已提交
2470

G
Guangliang Zhao 已提交
2471 2472 2473
		osd_req = rbd_osd_req_create(rbd_dev, op_type,
					(op_type == OBJ_OP_WRITE) ? 2 : 1,
					obj_request);
2474
		if (!osd_req)
2475
			goto out_unwind;
2476

2477
		obj_request->osd_req = osd_req;
2478
		obj_request->callback = rbd_img_obj_callback;
2479
		obj_request->img_offset = img_offset;
2480

2481
		rbd_img_obj_request_fill(obj_request, osd_req, op_type, 0);
A
Alex Elder 已提交
2482

2483
		img_offset += length;
A
Alex Elder 已提交
2484 2485 2486 2487 2488 2489 2490
		resid -= length;
	}

	return 0;

out_unwind:
	for_each_obj_request_safe(img_request, obj_request, next_obj_request)
2491
		rbd_img_obj_request_del(img_request, obj_request);
A
Alex Elder 已提交
2492 2493 2494 2495

	return -ENOMEM;
}

2496
static void
I
Ilya Dryomov 已提交
2497
rbd_osd_copyup_callback(struct rbd_obj_request *obj_request)
2498 2499 2500
{
	struct rbd_img_request *img_request;
	struct rbd_device *rbd_dev;
2501
	struct page **pages;
2502 2503
	u32 page_count;

I
Ilya Dryomov 已提交
2504 2505
	dout("%s: obj %p\n", __func__, obj_request);

2506 2507
	rbd_assert(obj_request->type == OBJ_REQUEST_BIO ||
		obj_request->type == OBJ_REQUEST_NODATA);
2508 2509 2510 2511 2512 2513 2514
	rbd_assert(obj_request_img_data_test(obj_request));
	img_request = obj_request->img_request;
	rbd_assert(img_request);

	rbd_dev = img_request->rbd_dev;
	rbd_assert(rbd_dev);

2515 2516
	pages = obj_request->copyup_pages;
	rbd_assert(pages != NULL);
2517
	obj_request->copyup_pages = NULL;
2518 2519 2520 2521
	page_count = obj_request->copyup_page_count;
	rbd_assert(page_count);
	obj_request->copyup_page_count = 0;
	ceph_release_page_vector(pages, page_count);
2522 2523 2524 2525 2526 2527 2528 2529 2530 2531

	/*
	 * We want the transfer count to reflect the size of the
	 * original write request.  There is no such thing as a
	 * successful short write, so if the request was successful
	 * we can just set it to the originally-requested length.
	 */
	if (!obj_request->result)
		obj_request->xferred = obj_request->length;

I
Ilya Dryomov 已提交
2532
	obj_request_done_set(obj_request);
2533 2534
}

2535 2536 2537 2538
static void
rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request)
{
	struct rbd_obj_request *orig_request;
2539 2540
	struct ceph_osd_request *osd_req;
	struct rbd_device *rbd_dev;
2541
	struct page **pages;
2542
	enum obj_operation_type op_type;
2543
	u32 page_count;
2544
	int img_result;
2545
	u64 parent_length;
2546 2547 2548 2549 2550 2551 2552 2553

	rbd_assert(img_request_child_test(img_request));

	/* First get what we need from the image request */

	pages = img_request->copyup_pages;
	rbd_assert(pages != NULL);
	img_request->copyup_pages = NULL;
2554 2555 2556
	page_count = img_request->copyup_page_count;
	rbd_assert(page_count);
	img_request->copyup_page_count = 0;
2557 2558 2559

	orig_request = img_request->obj_request;
	rbd_assert(orig_request != NULL);
2560
	rbd_assert(obj_request_type_valid(orig_request->type));
2561
	img_result = img_request->result;
2562
	parent_length = img_request->length;
2563
	rbd_assert(img_result || parent_length == img_request->xferred);
2564
	rbd_img_request_put(img_request);
2565

2566 2567
	rbd_assert(orig_request->img_request);
	rbd_dev = orig_request->img_request->rbd_dev;
2568 2569
	rbd_assert(rbd_dev);

2570 2571 2572 2573 2574 2575 2576
	/*
	 * If the overlap has become 0 (most likely because the
	 * image has been flattened) we need to free the pages
	 * and re-submit the original write request.
	 */
	if (!rbd_dev->parent_overlap) {
		ceph_release_page_vector(pages, page_count);
2577 2578
		rbd_obj_request_submit(orig_request);
		return;
2579
	}
2580

2581
	if (img_result)
2582 2583
		goto out_err;

2584 2585
	/*
	 * The original osd request is of no use to use any more.
2586
	 * We need a new one that can hold the three ops in a copyup
2587 2588 2589
	 * request.  Allocate the new copyup osd request for the
	 * original request, and release the old one.
	 */
2590
	img_result = -ENOMEM;
2591 2592 2593
	osd_req = rbd_osd_req_create_copyup(orig_request);
	if (!osd_req)
		goto out_err;
2594
	rbd_osd_req_destroy(orig_request->osd_req);
2595 2596
	orig_request->osd_req = osd_req;
	orig_request->copyup_pages = pages;
2597
	orig_request->copyup_page_count = page_count;
2598

2599
	/* Initialize the copyup op */
2600

2601
	osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup");
2602
	osd_req_op_cls_request_data_pages(osd_req, 0, pages, parent_length, 0,
2603
						false, false);
2604

2605
	/* Add the other op(s) */
2606

2607 2608
	op_type = rbd_img_request_op_type(orig_request->img_request);
	rbd_img_obj_request_fill(orig_request, osd_req, op_type, 1);
2609 2610 2611

	/* All set, send it off. */

2612 2613
	rbd_obj_request_submit(orig_request);
	return;
2614 2615

out_err:
2616
	ceph_release_page_vector(pages, page_count);
2617
	rbd_obj_request_error(orig_request, img_result);
2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630
}

/*
 * Read from the parent image the range of data that covers the
 * entire target of the given object request.  This is used for
 * satisfying a layered image write request when the target of an
 * object request from the image request does not exist.
 *
 * A page array big enough to hold the returned data is allocated
 * and supplied to rbd_img_request_fill() as the "data descriptor."
 * When the read completes, this page array will be transferred to
 * the original object request for the copyup operation.
 *
2631 2632
 * If an error occurs, it is recorded as the result of the original
 * object request in rbd_img_obj_exists_callback().
2633 2634 2635
 */
static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request)
{
2636
	struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev;
2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650
	struct rbd_img_request *parent_request = NULL;
	u64 img_offset;
	u64 length;
	struct page **pages = NULL;
	u32 page_count;
	int result;

	rbd_assert(rbd_dev->parent != NULL);

	/*
	 * Determine the byte range covered by the object in the
	 * child image to which the original request was to be sent.
	 */
	img_offset = obj_request->img_offset - obj_request->offset;
I
Ilya Dryomov 已提交
2651
	length = rbd_obj_bytes(&rbd_dev->header);
2652

A
Alex Elder 已提交
2653 2654 2655 2656 2657 2658 2659 2660 2661 2662
	/*
	 * There is no defined parent data beyond the parent
	 * overlap, so limit what we read at that boundary if
	 * necessary.
	 */
	if (img_offset + length > rbd_dev->parent_overlap) {
		rbd_assert(img_offset < rbd_dev->parent_overlap);
		length = rbd_dev->parent_overlap - img_offset;
	}

2663 2664 2665 2666 2667
	/*
	 * Allocate a page array big enough to receive the data read
	 * from the parent.
	 */
	page_count = (u32)calc_pages_for(0, length);
2668
	pages = ceph_alloc_page_vector(page_count, GFP_NOIO);
2669 2670 2671 2672 2673 2674 2675
	if (IS_ERR(pages)) {
		result = PTR_ERR(pages);
		pages = NULL;
		goto out_err;
	}

	result = -ENOMEM;
2676 2677
	parent_request = rbd_parent_request_create(obj_request,
						img_offset, length);
2678 2679 2680 2681 2682 2683
	if (!parent_request)
		goto out_err;

	result = rbd_img_request_fill(parent_request, OBJ_REQUEST_PAGES, pages);
	if (result)
		goto out_err;
2684

2685
	parent_request->copyup_pages = pages;
2686
	parent_request->copyup_page_count = page_count;
2687
	parent_request->callback = rbd_img_obj_parent_read_full_callback;
2688

2689 2690 2691 2692 2693
	result = rbd_img_request_submit(parent_request);
	if (!result)
		return 0;

	parent_request->copyup_pages = NULL;
2694
	parent_request->copyup_page_count = 0;
2695 2696 2697 2698 2699 2700 2701 2702 2703 2704
	parent_request->obj_request = NULL;
	rbd_obj_request_put(obj_request);
out_err:
	if (pages)
		ceph_release_page_vector(pages, page_count);
	if (parent_request)
		rbd_img_request_put(parent_request);
	return result;
}

2705 2706 2707
static void rbd_img_obj_exists_callback(struct rbd_obj_request *obj_request)
{
	struct rbd_obj_request *orig_request;
2708
	struct rbd_device *rbd_dev;
2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719
	int result;

	rbd_assert(!obj_request_img_data_test(obj_request));

	/*
	 * All we need from the object request is the original
	 * request and the result of the STAT op.  Grab those, then
	 * we're done with the request.
	 */
	orig_request = obj_request->obj_request;
	obj_request->obj_request = NULL;
2720
	rbd_obj_request_put(orig_request);
2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731
	rbd_assert(orig_request);
	rbd_assert(orig_request->img_request);

	result = obj_request->result;
	obj_request->result = 0;

	dout("%s: obj %p for obj %p result %d %llu/%llu\n", __func__,
		obj_request, orig_request, result,
		obj_request->xferred, obj_request->length);
	rbd_obj_request_put(obj_request);

2732 2733
	/*
	 * If the overlap has become 0 (most likely because the
2734 2735
	 * image has been flattened) we need to re-submit the
	 * original request.
2736 2737 2738
	 */
	rbd_dev = orig_request->img_request->rbd_dev;
	if (!rbd_dev->parent_overlap) {
2739 2740
		rbd_obj_request_submit(orig_request);
		return;
2741
	}
2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752

	/*
	 * Our only purpose here is to determine whether the object
	 * exists, and we don't want to treat the non-existence as
	 * an error.  If something else comes back, transfer the
	 * error to the original request and complete it now.
	 */
	if (!result) {
		obj_request_existence_set(orig_request, true);
	} else if (result == -ENOENT) {
		obj_request_existence_set(orig_request, false);
2753 2754
	} else {
		goto fail_orig_request;
2755 2756 2757 2758 2759 2760
	}

	/*
	 * Resubmit the original request now that we have recorded
	 * whether the target object exists.
	 */
2761 2762 2763 2764 2765 2766 2767
	result = rbd_img_obj_request_submit(orig_request);
	if (result)
		goto fail_orig_request;

	return;

fail_orig_request:
2768
	rbd_obj_request_error(orig_request, result);
2769 2770 2771 2772
}

static int rbd_img_obj_exists_submit(struct rbd_obj_request *obj_request)
{
2773
	struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev;
2774
	struct rbd_obj_request *stat_request;
2775
	struct page **pages;
2776 2777 2778 2779
	u32 page_count;
	size_t size;
	int ret;

2780
	stat_request = rbd_obj_request_create(OBJ_REQUEST_PAGES);
2781 2782 2783
	if (!stat_request)
		return -ENOMEM;

2784 2785
	stat_request->object_no = obj_request->object_no;

2786 2787 2788 2789 2790 2791 2792
	stat_request->osd_req = rbd_osd_req_create(rbd_dev, OBJ_OP_READ, 1,
						   stat_request);
	if (!stat_request->osd_req) {
		ret = -ENOMEM;
		goto fail_stat_request;
	}

2793 2794 2795 2796 2797 2798 2799 2800 2801 2802
	/*
	 * The response data for a STAT call consists of:
	 *     le64 length;
	 *     struct {
	 *         le32 tv_sec;
	 *         le32 tv_nsec;
	 *     } mtime;
	 */
	size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32);
	page_count = (u32)calc_pages_for(0, size);
2803
	pages = ceph_alloc_page_vector(page_count, GFP_NOIO);
2804 2805 2806 2807
	if (IS_ERR(pages)) {
		ret = PTR_ERR(pages);
		goto fail_stat_request;
	}
2808

2809 2810 2811
	osd_req_op_init(stat_request->osd_req, 0, CEPH_OSD_OP_STAT, 0);
	osd_req_op_raw_data_in_pages(stat_request->osd_req, 0, pages, size, 0,
				     false, false);
2812 2813 2814 2815 2816 2817 2818

	rbd_obj_request_get(obj_request);
	stat_request->obj_request = obj_request;
	stat_request->pages = pages;
	stat_request->page_count = page_count;
	stat_request->callback = rbd_img_obj_exists_callback;

2819 2820
	rbd_obj_request_submit(stat_request);
	return 0;
2821

2822 2823
fail_stat_request:
	rbd_obj_request_put(stat_request);
2824 2825 2826
	return ret;
}

2827
static bool img_obj_request_simple(struct rbd_obj_request *obj_request)
2828
{
2829 2830
	struct rbd_img_request *img_request = obj_request->img_request;
	struct rbd_device *rbd_dev = img_request->rbd_dev;
2831

2832
	/* Reads */
2833 2834
	if (!img_request_write_test(img_request) &&
	    !img_request_discard_test(img_request))
2835 2836 2837 2838 2839 2840
		return true;

	/* Non-layered writes */
	if (!img_request_layered_test(img_request))
		return true;

2841
	/*
2842 2843
	 * Layered writes outside of the parent overlap range don't
	 * share any data with the parent.
2844
	 */
2845 2846
	if (!obj_request_overlaps_parent(obj_request))
		return true;
2847

2848 2849 2850 2851 2852 2853 2854 2855
	/*
	 * Entire-object layered writes - we will overwrite whatever
	 * parent data there is anyway.
	 */
	if (!obj_request->offset &&
	    obj_request->length == rbd_obj_bytes(&rbd_dev->header))
		return true;

2856 2857 2858 2859 2860 2861 2862 2863 2864 2865 2866 2867 2868
	/*
	 * If the object is known to already exist, its parent data has
	 * already been copied.
	 */
	if (obj_request_known_test(obj_request) &&
	    obj_request_exists_test(obj_request))
		return true;

	return false;
}

static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request)
{
2869 2870 2871
	rbd_assert(obj_request_img_data_test(obj_request));
	rbd_assert(obj_request_type_valid(obj_request->type));
	rbd_assert(obj_request->img_request);
2872

2873
	if (img_obj_request_simple(obj_request)) {
2874 2875
		rbd_obj_request_submit(obj_request);
		return 0;
2876 2877 2878
	}

	/*
2879 2880 2881 2882
	 * It's a layered write.  The target object might exist but
	 * we may not know that yet.  If we know it doesn't exist,
	 * start by reading the data for the full target object from
	 * the parent so we can use it for a copyup to the target.
2883
	 */
2884
	if (obj_request_known_test(obj_request))
2885 2886 2887
		return rbd_img_obj_parent_read_full(obj_request);

	/* We don't know whether the target exists.  Go find out. */
2888 2889 2890 2891

	return rbd_img_obj_exists_submit(obj_request);
}

A
Alex Elder 已提交
2892 2893 2894
static int rbd_img_request_submit(struct rbd_img_request *img_request)
{
	struct rbd_obj_request *obj_request;
2895
	struct rbd_obj_request *next_obj_request;
2896
	int ret = 0;
A
Alex Elder 已提交
2897

A
Alex Elder 已提交
2898
	dout("%s: img %p\n", __func__, img_request);
A
Alex Elder 已提交
2899

2900 2901
	rbd_img_request_get(img_request);
	for_each_obj_request_safe(img_request, obj_request, next_obj_request) {
2902
		ret = rbd_img_obj_request_submit(obj_request);
A
Alex Elder 已提交
2903
		if (ret)
2904
			goto out_put_ireq;
A
Alex Elder 已提交
2905 2906
	}

2907 2908 2909
out_put_ireq:
	rbd_img_request_put(img_request);
	return ret;
A
Alex Elder 已提交
2910
}
A
Alex Elder 已提交
2911 2912 2913 2914

static void rbd_img_parent_read_callback(struct rbd_img_request *img_request)
{
	struct rbd_obj_request *obj_request;
A
Alex Elder 已提交
2915 2916
	struct rbd_device *rbd_dev;
	u64 obj_end;
2917 2918
	u64 img_xferred;
	int img_result;
A
Alex Elder 已提交
2919 2920 2921

	rbd_assert(img_request_child_test(img_request));

2922 2923
	/* First get what we need from the image request and release it */

A
Alex Elder 已提交
2924
	obj_request = img_request->obj_request;
2925 2926 2927 2928 2929 2930 2931 2932 2933
	img_xferred = img_request->xferred;
	img_result = img_request->result;
	rbd_img_request_put(img_request);

	/*
	 * If the overlap has become 0 (most likely because the
	 * image has been flattened) we need to re-submit the
	 * original request.
	 */
A
Alex Elder 已提交
2934 2935
	rbd_assert(obj_request);
	rbd_assert(obj_request->img_request);
2936 2937
	rbd_dev = obj_request->img_request->rbd_dev;
	if (!rbd_dev->parent_overlap) {
2938 2939
		rbd_obj_request_submit(obj_request);
		return;
2940
	}
A
Alex Elder 已提交
2941

2942
	obj_request->result = img_result;
A
Alex Elder 已提交
2943 2944 2945 2946 2947 2948 2949 2950 2951 2952 2953 2954 2955 2956 2957 2958 2959 2960
	if (obj_request->result)
		goto out;

	/*
	 * We need to zero anything beyond the parent overlap
	 * boundary.  Since rbd_img_obj_request_read_callback()
	 * will zero anything beyond the end of a short read, an
	 * easy way to do this is to pretend the data from the
	 * parent came up short--ending at the overlap boundary.
	 */
	rbd_assert(obj_request->img_offset < U64_MAX - obj_request->length);
	obj_end = obj_request->img_offset + obj_request->length;
	if (obj_end > rbd_dev->parent_overlap) {
		u64 xferred = 0;

		if (obj_request->img_offset < rbd_dev->parent_overlap)
			xferred = rbd_dev->parent_overlap -
					obj_request->img_offset;
A
Alex Elder 已提交
2961

2962
		obj_request->xferred = min(img_xferred, xferred);
A
Alex Elder 已提交
2963
	} else {
2964
		obj_request->xferred = img_xferred;
A
Alex Elder 已提交
2965 2966
	}
out:
A
Alex Elder 已提交
2967 2968 2969 2970 2971 2972 2973 2974 2975 2976 2977 2978
	rbd_img_obj_request_read_callback(obj_request);
	rbd_obj_request_complete(obj_request);
}

static void rbd_img_parent_read(struct rbd_obj_request *obj_request)
{
	struct rbd_img_request *img_request;
	int result;

	rbd_assert(obj_request_img_data_test(obj_request));
	rbd_assert(obj_request->img_request != NULL);
	rbd_assert(obj_request->result == (s32) -ENOENT);
2979
	rbd_assert(obj_request_type_valid(obj_request->type));
A
Alex Elder 已提交
2980 2981

	/* rbd_read_finish(obj_request, obj_request->length); */
2982
	img_request = rbd_parent_request_create(obj_request,
A
Alex Elder 已提交
2983
						obj_request->img_offset,
2984
						obj_request->length);
A
Alex Elder 已提交
2985 2986 2987 2988
	result = -ENOMEM;
	if (!img_request)
		goto out_err;

2989 2990 2991 2992 2993 2994
	if (obj_request->type == OBJ_REQUEST_BIO)
		result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
						obj_request->bio_list);
	else
		result = rbd_img_request_fill(img_request, OBJ_REQUEST_PAGES,
						obj_request->pages);
A
Alex Elder 已提交
2995 2996 2997 2998 2999 3000 3001 3002 3003 3004 3005 3006 3007 3008 3009 3010
	if (result)
		goto out_err;

	img_request->callback = rbd_img_parent_read_callback;
	result = rbd_img_request_submit(img_request);
	if (result)
		goto out_err;

	return;
out_err:
	if (img_request)
		rbd_img_request_put(img_request);
	obj_request->result = result;
	obj_request->xferred = 0;
	obj_request_done_set(obj_request);
}
A
Alex Elder 已提交
3011

3012
static const struct rbd_client_id rbd_empty_cid;
A
Alex Elder 已提交
3013

3014 3015 3016 3017 3018 3019 3020 3021 3022 3023 3024 3025 3026 3027 3028 3029 3030 3031 3032 3033 3034 3035 3036 3037 3038 3039 3040 3041 3042 3043 3044 3045 3046 3047 3048 3049
static bool rbd_cid_equal(const struct rbd_client_id *lhs,
			  const struct rbd_client_id *rhs)
{
	return lhs->gid == rhs->gid && lhs->handle == rhs->handle;
}

static struct rbd_client_id rbd_get_cid(struct rbd_device *rbd_dev)
{
	struct rbd_client_id cid;

	mutex_lock(&rbd_dev->watch_mutex);
	cid.gid = ceph_client_gid(rbd_dev->rbd_client->client);
	cid.handle = rbd_dev->watch_cookie;
	mutex_unlock(&rbd_dev->watch_mutex);
	return cid;
}

/*
 * lock_rwsem must be held for write
 */
static void rbd_set_owner_cid(struct rbd_device *rbd_dev,
			      const struct rbd_client_id *cid)
{
	dout("%s rbd_dev %p %llu-%llu -> %llu-%llu\n", __func__, rbd_dev,
	     rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle,
	     cid->gid, cid->handle);
	rbd_dev->owner_cid = *cid; /* struct */
}

static void format_lock_cookie(struct rbd_device *rbd_dev, char *buf)
{
	mutex_lock(&rbd_dev->watch_mutex);
	sprintf(buf, "%s %llu", RBD_LOCK_COOKIE_PREFIX, rbd_dev->watch_cookie);
	mutex_unlock(&rbd_dev->watch_mutex);
}

3050 3051 3052 3053 3054 3055 3056 3057 3058
static void __rbd_lock(struct rbd_device *rbd_dev, const char *cookie)
{
	struct rbd_client_id cid = rbd_get_cid(rbd_dev);

	strcpy(rbd_dev->lock_cookie, cookie);
	rbd_set_owner_cid(rbd_dev, &cid);
	queue_work(rbd_dev->task_wq, &rbd_dev->acquired_lock_work);
}

3059 3060 3061 3062
/*
 * lock_rwsem must be held for write
 */
static int rbd_lock(struct rbd_device *rbd_dev)
A
Alex Elder 已提交
3063
{
3064
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3065
	char cookie[32];
3066
	int ret;
A
Alex Elder 已提交
3067

I
Ilya Dryomov 已提交
3068 3069
	WARN_ON(__rbd_is_lock_owner(rbd_dev) ||
		rbd_dev->lock_cookie[0] != '\0');
3070

3071 3072 3073 3074
	format_lock_cookie(rbd_dev, cookie);
	ret = ceph_cls_lock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
			    RBD_LOCK_NAME, CEPH_CLS_LOCK_EXCLUSIVE, cookie,
			    RBD_LOCK_TAG, "", 0);
3075
	if (ret)
3076
		return ret;
A
Alex Elder 已提交
3077

3078
	rbd_dev->lock_state = RBD_LOCK_STATE_LOCKED;
3079
	__rbd_lock(rbd_dev, cookie);
3080
	return 0;
A
Alex Elder 已提交
3081 3082
}

3083 3084 3085
/*
 * lock_rwsem must be held for write
 */
I
Ilya Dryomov 已提交
3086
static void rbd_unlock(struct rbd_device *rbd_dev)
3087
{
3088
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3089 3090
	int ret;

I
Ilya Dryomov 已提交
3091 3092
	WARN_ON(!__rbd_is_lock_owner(rbd_dev) ||
		rbd_dev->lock_cookie[0] == '\0');
3093

3094
	ret = ceph_cls_unlock(osdc, &rbd_dev->header_oid, &rbd_dev->header_oloc,
I
Ilya Dryomov 已提交
3095
			      RBD_LOCK_NAME, rbd_dev->lock_cookie);
I
Ilya Dryomov 已提交
3096 3097
	if (ret && ret != -ENOENT)
		rbd_warn(rbd_dev, "failed to unlock: %d", ret);
3098

I
Ilya Dryomov 已提交
3099 3100
	/* treat errors as the image is unlocked */
	rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED;
I
Ilya Dryomov 已提交
3101
	rbd_dev->lock_cookie[0] = '\0';
3102 3103
	rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
	queue_work(rbd_dev->task_wq, &rbd_dev->released_lock_work);
3104 3105
}

3106 3107 3108 3109
static int __rbd_notify_op_lock(struct rbd_device *rbd_dev,
				enum rbd_notify_op notify_op,
				struct page ***preply_pages,
				size_t *preply_len)
3110 3111
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3112 3113 3114 3115
	struct rbd_client_id cid = rbd_get_cid(rbd_dev);
	int buf_size = 4 + 8 + 8 + CEPH_ENCODING_START_BLK_LEN;
	char buf[buf_size];
	void *p = buf;
3116

3117
	dout("%s rbd_dev %p notify_op %d\n", __func__, rbd_dev, notify_op);
3118

3119 3120 3121 3122 3123
	/* encode *LockPayload NotifyMessage (op + ClientId) */
	ceph_start_encoding(&p, 2, 1, buf_size - CEPH_ENCODING_START_BLK_LEN);
	ceph_encode_32(&p, notify_op);
	ceph_encode_64(&p, cid.gid);
	ceph_encode_64(&p, cid.handle);
3124

3125 3126 3127
	return ceph_osdc_notify(osdc, &rbd_dev->header_oid,
				&rbd_dev->header_oloc, buf, buf_size,
				RBD_NOTIFY_TIMEOUT, preply_pages, preply_len);
3128 3129
}

3130 3131
static void rbd_notify_op_lock(struct rbd_device *rbd_dev,
			       enum rbd_notify_op notify_op)
3132
{
3133 3134
	struct page **reply_pages;
	size_t reply_len;
3135

3136 3137 3138
	__rbd_notify_op_lock(rbd_dev, notify_op, &reply_pages, &reply_len);
	ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len));
}
3139

3140 3141 3142 3143
static void rbd_notify_acquired_lock(struct work_struct *work)
{
	struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
						  acquired_lock_work);
3144

3145
	rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_ACQUIRED_LOCK);
3146 3147
}

3148
static void rbd_notify_released_lock(struct work_struct *work)
3149
{
3150 3151
	struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
						  released_lock_work);
I
Ilya Dryomov 已提交
3152

3153
	rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_RELEASED_LOCK);
3154 3155
}

3156
static int rbd_request_lock(struct rbd_device *rbd_dev)
3157
{
3158 3159 3160
	struct page **reply_pages;
	size_t reply_len;
	bool lock_owner_responded = false;
3161 3162
	int ret;

3163
	dout("%s rbd_dev %p\n", __func__, rbd_dev);
3164

3165 3166 3167 3168
	ret = __rbd_notify_op_lock(rbd_dev, RBD_NOTIFY_OP_REQUEST_LOCK,
				   &reply_pages, &reply_len);
	if (ret && ret != -ETIMEDOUT) {
		rbd_warn(rbd_dev, "failed to request lock: %d", ret);
3169
		goto out;
3170
	}
3171

3172 3173 3174 3175
	if (reply_len > 0 && reply_len <= PAGE_SIZE) {
		void *p = page_address(reply_pages[0]);
		void *const end = p + reply_len;
		u32 n;
3176

3177 3178 3179 3180
		ceph_decode_32_safe(&p, end, n, e_inval); /* num_acks */
		while (n--) {
			u8 struct_v;
			u32 len;
3181

3182 3183
			ceph_decode_need(&p, end, 8 + 8, e_inval);
			p += 8 + 8; /* skip gid and cookie */
3184

3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219 3220 3221 3222 3223 3224 3225 3226 3227 3228 3229 3230 3231 3232 3233 3234 3235 3236 3237 3238 3239 3240 3241 3242 3243 3244 3245 3246 3247 3248 3249 3250 3251 3252 3253 3254 3255 3256 3257 3258 3259 3260 3261 3262 3263 3264 3265 3266 3267 3268 3269 3270 3271 3272 3273 3274 3275 3276 3277 3278 3279 3280 3281 3282 3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303 3304 3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337 3338 3339 3340 3341 3342 3343 3344 3345 3346 3347 3348 3349 3350 3351 3352 3353 3354 3355 3356 3357 3358 3359 3360 3361 3362 3363 3364 3365 3366 3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380 3381 3382 3383 3384 3385 3386 3387 3388 3389 3390 3391 3392 3393 3394 3395 3396 3397 3398 3399 3400 3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416
			ceph_decode_32_safe(&p, end, len, e_inval);
			if (!len)
				continue;

			if (lock_owner_responded) {
				rbd_warn(rbd_dev,
					 "duplicate lock owners detected");
				ret = -EIO;
				goto out;
			}

			lock_owner_responded = true;
			ret = ceph_start_decoding(&p, end, 1, "ResponseMessage",
						  &struct_v, &len);
			if (ret) {
				rbd_warn(rbd_dev,
					 "failed to decode ResponseMessage: %d",
					 ret);
				goto e_inval;
			}

			ret = ceph_decode_32(&p);
		}
	}

	if (!lock_owner_responded) {
		rbd_warn(rbd_dev, "no lock owners detected");
		ret = -ETIMEDOUT;
	}

out:
	ceph_release_page_vector(reply_pages, calc_pages_for(0, reply_len));
	return ret;

e_inval:
	ret = -EINVAL;
	goto out;
}

static void wake_requests(struct rbd_device *rbd_dev, bool wake_all)
{
	dout("%s rbd_dev %p wake_all %d\n", __func__, rbd_dev, wake_all);

	cancel_delayed_work(&rbd_dev->lock_dwork);
	if (wake_all)
		wake_up_all(&rbd_dev->lock_waitq);
	else
		wake_up(&rbd_dev->lock_waitq);
}

static int get_lock_owner_info(struct rbd_device *rbd_dev,
			       struct ceph_locker **lockers, u32 *num_lockers)
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	u8 lock_type;
	char *lock_tag;
	int ret;

	dout("%s rbd_dev %p\n", __func__, rbd_dev);

	ret = ceph_cls_lock_info(osdc, &rbd_dev->header_oid,
				 &rbd_dev->header_oloc, RBD_LOCK_NAME,
				 &lock_type, &lock_tag, lockers, num_lockers);
	if (ret)
		return ret;

	if (*num_lockers == 0) {
		dout("%s rbd_dev %p no lockers detected\n", __func__, rbd_dev);
		goto out;
	}

	if (strcmp(lock_tag, RBD_LOCK_TAG)) {
		rbd_warn(rbd_dev, "locked by external mechanism, tag %s",
			 lock_tag);
		ret = -EBUSY;
		goto out;
	}

	if (lock_type == CEPH_CLS_LOCK_SHARED) {
		rbd_warn(rbd_dev, "shared lock type detected");
		ret = -EBUSY;
		goto out;
	}

	if (strncmp((*lockers)[0].id.cookie, RBD_LOCK_COOKIE_PREFIX,
		    strlen(RBD_LOCK_COOKIE_PREFIX))) {
		rbd_warn(rbd_dev, "locked by external mechanism, cookie %s",
			 (*lockers)[0].id.cookie);
		ret = -EBUSY;
		goto out;
	}

out:
	kfree(lock_tag);
	return ret;
}

static int find_watcher(struct rbd_device *rbd_dev,
			const struct ceph_locker *locker)
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	struct ceph_watch_item *watchers;
	u32 num_watchers;
	u64 cookie;
	int i;
	int ret;

	ret = ceph_osdc_list_watchers(osdc, &rbd_dev->header_oid,
				      &rbd_dev->header_oloc, &watchers,
				      &num_watchers);
	if (ret)
		return ret;

	sscanf(locker->id.cookie, RBD_LOCK_COOKIE_PREFIX " %llu", &cookie);
	for (i = 0; i < num_watchers; i++) {
		if (!memcmp(&watchers[i].addr, &locker->info.addr,
			    sizeof(locker->info.addr)) &&
		    watchers[i].cookie == cookie) {
			struct rbd_client_id cid = {
				.gid = le64_to_cpu(watchers[i].name.num),
				.handle = cookie,
			};

			dout("%s rbd_dev %p found cid %llu-%llu\n", __func__,
			     rbd_dev, cid.gid, cid.handle);
			rbd_set_owner_cid(rbd_dev, &cid);
			ret = 1;
			goto out;
		}
	}

	dout("%s rbd_dev %p no watchers\n", __func__, rbd_dev);
	ret = 0;
out:
	kfree(watchers);
	return ret;
}

/*
 * lock_rwsem must be held for write
 */
static int rbd_try_lock(struct rbd_device *rbd_dev)
{
	struct ceph_client *client = rbd_dev->rbd_client->client;
	struct ceph_locker *lockers;
	u32 num_lockers;
	int ret;

	for (;;) {
		ret = rbd_lock(rbd_dev);
		if (ret != -EBUSY)
			return ret;

		/* determine if the current lock holder is still alive */
		ret = get_lock_owner_info(rbd_dev, &lockers, &num_lockers);
		if (ret)
			return ret;

		if (num_lockers == 0)
			goto again;

		ret = find_watcher(rbd_dev, lockers);
		if (ret) {
			if (ret > 0)
				ret = 0; /* have to request lock */
			goto out;
		}

		rbd_warn(rbd_dev, "%s%llu seems dead, breaking lock",
			 ENTITY_NAME(lockers[0].id.name));

		ret = ceph_monc_blacklist_add(&client->monc,
					      &lockers[0].info.addr);
		if (ret) {
			rbd_warn(rbd_dev, "blacklist of %s%llu failed: %d",
				 ENTITY_NAME(lockers[0].id.name), ret);
			goto out;
		}

		ret = ceph_cls_break_lock(&client->osdc, &rbd_dev->header_oid,
					  &rbd_dev->header_oloc, RBD_LOCK_NAME,
					  lockers[0].id.cookie,
					  &lockers[0].id.name);
		if (ret && ret != -ENOENT)
			goto out;

again:
		ceph_free_lockers(lockers, num_lockers);
	}

out:
	ceph_free_lockers(lockers, num_lockers);
	return ret;
}

/*
 * ret is set only if lock_state is RBD_LOCK_STATE_UNLOCKED
 */
static enum rbd_lock_state rbd_try_acquire_lock(struct rbd_device *rbd_dev,
						int *pret)
{
	enum rbd_lock_state lock_state;

	down_read(&rbd_dev->lock_rwsem);
	dout("%s rbd_dev %p read lock_state %d\n", __func__, rbd_dev,
	     rbd_dev->lock_state);
	if (__rbd_is_lock_owner(rbd_dev)) {
		lock_state = rbd_dev->lock_state;
		up_read(&rbd_dev->lock_rwsem);
		return lock_state;
	}

	up_read(&rbd_dev->lock_rwsem);
	down_write(&rbd_dev->lock_rwsem);
	dout("%s rbd_dev %p write lock_state %d\n", __func__, rbd_dev,
	     rbd_dev->lock_state);
	if (!__rbd_is_lock_owner(rbd_dev)) {
		*pret = rbd_try_lock(rbd_dev);
		if (*pret)
			rbd_warn(rbd_dev, "failed to acquire lock: %d", *pret);
	}

	lock_state = rbd_dev->lock_state;
	up_write(&rbd_dev->lock_rwsem);
	return lock_state;
}

static void rbd_acquire_lock(struct work_struct *work)
{
	struct rbd_device *rbd_dev = container_of(to_delayed_work(work),
					    struct rbd_device, lock_dwork);
	enum rbd_lock_state lock_state;
3417
	int ret = 0;
3418 3419 3420 3421 3422 3423 3424 3425 3426 3427 3428 3429 3430 3431 3432

	dout("%s rbd_dev %p\n", __func__, rbd_dev);
again:
	lock_state = rbd_try_acquire_lock(rbd_dev, &ret);
	if (lock_state != RBD_LOCK_STATE_UNLOCKED || ret == -EBLACKLISTED) {
		if (lock_state == RBD_LOCK_STATE_LOCKED)
			wake_requests(rbd_dev, true);
		dout("%s rbd_dev %p lock_state %d ret %d - done\n", __func__,
		     rbd_dev, lock_state, ret);
		return;
	}

	ret = rbd_request_lock(rbd_dev);
	if (ret == -ETIMEDOUT) {
		goto again; /* treat this as a dead client */
I
Ilya Dryomov 已提交
3433 3434 3435 3436 3437 3438 3439 3440 3441 3442 3443 3444
	} else if (ret == -EROFS) {
		rbd_warn(rbd_dev, "peer will not release lock");
		/*
		 * If this is rbd_add_acquire_lock(), we want to fail
		 * immediately -- reuse BLACKLISTED flag.  Otherwise we
		 * want to block.
		 */
		if (!(rbd_dev->disk->flags & GENHD_FL_UP)) {
			set_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags);
			/* wake "rbd map --exclusive" process */
			wake_requests(rbd_dev, false);
		}
3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458 3459 3460 3461 3462 3463 3464 3465 3466 3467 3468 3469 3470 3471 3472
	} else if (ret < 0) {
		rbd_warn(rbd_dev, "error requesting lock: %d", ret);
		mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
				 RBD_RETRY_DELAY);
	} else {
		/*
		 * lock owner acked, but resend if we don't see them
		 * release the lock
		 */
		dout("%s rbd_dev %p requeueing lock_dwork\n", __func__,
		     rbd_dev);
		mod_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork,
		    msecs_to_jiffies(2 * RBD_NOTIFY_TIMEOUT * MSEC_PER_SEC));
	}
}

/*
 * lock_rwsem must be held for write
 */
static bool rbd_release_lock(struct rbd_device *rbd_dev)
{
	dout("%s rbd_dev %p read lock_state %d\n", __func__, rbd_dev,
	     rbd_dev->lock_state);
	if (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED)
		return false;

	rbd_dev->lock_state = RBD_LOCK_STATE_RELEASING;
	downgrade_write(&rbd_dev->lock_rwsem);
3473
	/*
3474
	 * Ensure that all in-flight IO is flushed.
3475
	 *
3476 3477
	 * FIXME: ceph_osdc_sync() flushes the entire OSD client, which
	 * may be shared with other devices.
3478
	 */
3479 3480 3481 3482 3483 3484 3485 3486 3487
	ceph_osdc_sync(&rbd_dev->rbd_client->client->osdc);
	up_read(&rbd_dev->lock_rwsem);

	down_write(&rbd_dev->lock_rwsem);
	dout("%s rbd_dev %p write lock_state %d\n", __func__, rbd_dev,
	     rbd_dev->lock_state);
	if (rbd_dev->lock_state != RBD_LOCK_STATE_RELEASING)
		return false;

I
Ilya Dryomov 已提交
3488 3489 3490 3491 3492 3493 3494 3495 3496
	rbd_unlock(rbd_dev);
	/*
	 * Give others a chance to grab the lock - we would re-acquire
	 * almost immediately if we got new IO during ceph_osdc_sync()
	 * otherwise.  We need to ack our own notifications, so this
	 * lock_dwork will be requeued from rbd_wait_state_locked()
	 * after wake_requests() in rbd_handle_released_lock().
	 */
	cancel_delayed_work(&rbd_dev->lock_dwork);
3497 3498 3499 3500 3501 3502 3503 3504 3505 3506 3507 3508 3509 3510 3511 3512 3513 3514 3515 3516 3517 3518 3519 3520 3521 3522 3523 3524 3525 3526 3527 3528 3529 3530 3531 3532 3533 3534 3535 3536 3537 3538 3539 3540 3541 3542 3543 3544 3545 3546 3547 3548 3549 3550 3551 3552 3553 3554 3555 3556 3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568 3569 3570 3571 3572 3573 3574 3575 3576
	return true;
}

static void rbd_release_lock_work(struct work_struct *work)
{
	struct rbd_device *rbd_dev = container_of(work, struct rbd_device,
						  unlock_work);

	down_write(&rbd_dev->lock_rwsem);
	rbd_release_lock(rbd_dev);
	up_write(&rbd_dev->lock_rwsem);
}

static void rbd_handle_acquired_lock(struct rbd_device *rbd_dev, u8 struct_v,
				     void **p)
{
	struct rbd_client_id cid = { 0 };

	if (struct_v >= 2) {
		cid.gid = ceph_decode_64(p);
		cid.handle = ceph_decode_64(p);
	}

	dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
	     cid.handle);
	if (!rbd_cid_equal(&cid, &rbd_empty_cid)) {
		down_write(&rbd_dev->lock_rwsem);
		if (rbd_cid_equal(&cid, &rbd_dev->owner_cid)) {
			/*
			 * we already know that the remote client is
			 * the owner
			 */
			up_write(&rbd_dev->lock_rwsem);
			return;
		}

		rbd_set_owner_cid(rbd_dev, &cid);
		downgrade_write(&rbd_dev->lock_rwsem);
	} else {
		down_read(&rbd_dev->lock_rwsem);
	}

	if (!__rbd_is_lock_owner(rbd_dev))
		wake_requests(rbd_dev, false);
	up_read(&rbd_dev->lock_rwsem);
}

static void rbd_handle_released_lock(struct rbd_device *rbd_dev, u8 struct_v,
				     void **p)
{
	struct rbd_client_id cid = { 0 };

	if (struct_v >= 2) {
		cid.gid = ceph_decode_64(p);
		cid.handle = ceph_decode_64(p);
	}

	dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
	     cid.handle);
	if (!rbd_cid_equal(&cid, &rbd_empty_cid)) {
		down_write(&rbd_dev->lock_rwsem);
		if (!rbd_cid_equal(&cid, &rbd_dev->owner_cid)) {
			dout("%s rbd_dev %p unexpected owner, cid %llu-%llu != owner_cid %llu-%llu\n",
			     __func__, rbd_dev, cid.gid, cid.handle,
			     rbd_dev->owner_cid.gid, rbd_dev->owner_cid.handle);
			up_write(&rbd_dev->lock_rwsem);
			return;
		}

		rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
		downgrade_write(&rbd_dev->lock_rwsem);
	} else {
		down_read(&rbd_dev->lock_rwsem);
	}

	if (!__rbd_is_lock_owner(rbd_dev))
		wake_requests(rbd_dev, false);
	up_read(&rbd_dev->lock_rwsem);
}

3577 3578 3579 3580 3581 3582
/*
 * Returns result for ResponseMessage to be encoded (<= 0), or 1 if no
 * ResponseMessage is needed.
 */
static int rbd_handle_request_lock(struct rbd_device *rbd_dev, u8 struct_v,
				   void **p)
3583 3584 3585
{
	struct rbd_client_id my_cid = rbd_get_cid(rbd_dev);
	struct rbd_client_id cid = { 0 };
3586
	int result = 1;
3587 3588 3589 3590 3591 3592 3593 3594 3595

	if (struct_v >= 2) {
		cid.gid = ceph_decode_64(p);
		cid.handle = ceph_decode_64(p);
	}

	dout("%s rbd_dev %p cid %llu-%llu\n", __func__, rbd_dev, cid.gid,
	     cid.handle);
	if (rbd_cid_equal(&cid, &my_cid))
3596
		return result;
3597 3598

	down_read(&rbd_dev->lock_rwsem);
3599 3600 3601 3602 3603 3604 3605 3606 3607 3608 3609 3610
	if (__rbd_is_lock_owner(rbd_dev)) {
		if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED &&
		    rbd_cid_equal(&rbd_dev->owner_cid, &rbd_empty_cid))
			goto out_unlock;

		/*
		 * encode ResponseMessage(0) so the peer can detect
		 * a missing owner
		 */
		result = 0;

		if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED) {
I
Ilya Dryomov 已提交
3611 3612 3613 3614 3615 3616 3617 3618 3619
			if (!rbd_dev->opts->exclusive) {
				dout("%s rbd_dev %p queueing unlock_work\n",
				     __func__, rbd_dev);
				queue_work(rbd_dev->task_wq,
					   &rbd_dev->unlock_work);
			} else {
				/* refuse to release the lock */
				result = -EROFS;
			}
3620 3621
		}
	}
3622 3623

out_unlock:
3624
	up_read(&rbd_dev->lock_rwsem);
3625
	return result;
3626 3627 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 3642 3643 3644 3645
}

static void __rbd_acknowledge_notify(struct rbd_device *rbd_dev,
				     u64 notify_id, u64 cookie, s32 *result)
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	int buf_size = 4 + CEPH_ENCODING_START_BLK_LEN;
	char buf[buf_size];
	int ret;

	if (result) {
		void *p = buf;

		/* encode ResponseMessage */
		ceph_start_encoding(&p, 1, 1,
				    buf_size - CEPH_ENCODING_START_BLK_LEN);
		ceph_encode_32(&p, *result);
	} else {
		buf_size = 0;
	}
A
Alex Elder 已提交
3646

3647 3648
	ret = ceph_osdc_notify_ack(osdc, &rbd_dev->header_oid,
				   &rbd_dev->header_oloc, notify_id, cookie,
3649
				   buf, buf_size);
3650
	if (ret)
3651 3652 3653 3654 3655 3656 3657 3658 3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673
		rbd_warn(rbd_dev, "acknowledge_notify failed: %d", ret);
}

static void rbd_acknowledge_notify(struct rbd_device *rbd_dev, u64 notify_id,
				   u64 cookie)
{
	dout("%s rbd_dev %p\n", __func__, rbd_dev);
	__rbd_acknowledge_notify(rbd_dev, notify_id, cookie, NULL);
}

static void rbd_acknowledge_notify_result(struct rbd_device *rbd_dev,
					  u64 notify_id, u64 cookie, s32 result)
{
	dout("%s rbd_dev %p result %d\n", __func__, rbd_dev, result);
	__rbd_acknowledge_notify(rbd_dev, notify_id, cookie, &result);
}

static void rbd_watch_cb(void *arg, u64 notify_id, u64 cookie,
			 u64 notifier_id, void *data, size_t data_len)
{
	struct rbd_device *rbd_dev = arg;
	void *p = data;
	void *const end = p + data_len;
3674
	u8 struct_v = 0;
3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707
	u32 len;
	u32 notify_op;
	int ret;

	dout("%s rbd_dev %p cookie %llu notify_id %llu data_len %zu\n",
	     __func__, rbd_dev, cookie, notify_id, data_len);
	if (data_len) {
		ret = ceph_start_decoding(&p, end, 1, "NotifyMessage",
					  &struct_v, &len);
		if (ret) {
			rbd_warn(rbd_dev, "failed to decode NotifyMessage: %d",
				 ret);
			return;
		}

		notify_op = ceph_decode_32(&p);
	} else {
		/* legacy notification for header updates */
		notify_op = RBD_NOTIFY_OP_HEADER_UPDATE;
		len = 0;
	}

	dout("%s rbd_dev %p notify_op %u\n", __func__, rbd_dev, notify_op);
	switch (notify_op) {
	case RBD_NOTIFY_OP_ACQUIRED_LOCK:
		rbd_handle_acquired_lock(rbd_dev, struct_v, &p);
		rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
		break;
	case RBD_NOTIFY_OP_RELEASED_LOCK:
		rbd_handle_released_lock(rbd_dev, struct_v, &p);
		rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
		break;
	case RBD_NOTIFY_OP_REQUEST_LOCK:
3708 3709
		ret = rbd_handle_request_lock(rbd_dev, struct_v, &p);
		if (ret <= 0)
3710
			rbd_acknowledge_notify_result(rbd_dev, notify_id,
3711
						      cookie, ret);
3712 3713 3714 3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728 3729
		else
			rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
		break;
	case RBD_NOTIFY_OP_HEADER_UPDATE:
		ret = rbd_dev_refresh(rbd_dev);
		if (ret)
			rbd_warn(rbd_dev, "refresh failed: %d", ret);

		rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
		break;
	default:
		if (rbd_is_lock_owner(rbd_dev))
			rbd_acknowledge_notify_result(rbd_dev, notify_id,
						      cookie, -EOPNOTSUPP);
		else
			rbd_acknowledge_notify(rbd_dev, notify_id, cookie);
		break;
	}
A
Alex Elder 已提交
3730 3731
}

3732 3733
static void __rbd_unregister_watch(struct rbd_device *rbd_dev);

3734
static void rbd_watch_errcb(void *arg, u64 cookie, int err)
3735
{
3736
	struct rbd_device *rbd_dev = arg;
3737

3738
	rbd_warn(rbd_dev, "encountered watch error: %d", err);
3739

3740 3741 3742 3743
	down_write(&rbd_dev->lock_rwsem);
	rbd_set_owner_cid(rbd_dev, &rbd_empty_cid);
	up_write(&rbd_dev->lock_rwsem);

3744 3745 3746 3747
	mutex_lock(&rbd_dev->watch_mutex);
	if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED) {
		__rbd_unregister_watch(rbd_dev);
		rbd_dev->watch_state = RBD_WATCH_STATE_ERROR;
3748

3749
		queue_delayed_work(rbd_dev->task_wq, &rbd_dev->watch_dwork, 0);
3750
	}
3751
	mutex_unlock(&rbd_dev->watch_mutex);
3752 3753
}

3754
/*
3755
 * watch_mutex must be locked
3756
 */
3757
static int __rbd_register_watch(struct rbd_device *rbd_dev)
3758 3759
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
3760
	struct ceph_osd_linger_request *handle;
3761

3762
	rbd_assert(!rbd_dev->watch_handle);
3763
	dout("%s rbd_dev %p\n", __func__, rbd_dev);
3764

3765 3766 3767 3768 3769
	handle = ceph_osdc_watch(osdc, &rbd_dev->header_oid,
				 &rbd_dev->header_oloc, rbd_watch_cb,
				 rbd_watch_errcb, rbd_dev);
	if (IS_ERR(handle))
		return PTR_ERR(handle);
3770

3771
	rbd_dev->watch_handle = handle;
3772 3773 3774
	return 0;
}

3775 3776 3777 3778
/*
 * watch_mutex must be locked
 */
static void __rbd_unregister_watch(struct rbd_device *rbd_dev)
3779
{
3780 3781
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	int ret;
3782

3783 3784
	rbd_assert(rbd_dev->watch_handle);
	dout("%s rbd_dev %p\n", __func__, rbd_dev);
3785

3786 3787 3788
	ret = ceph_osdc_unwatch(osdc, rbd_dev->watch_handle);
	if (ret)
		rbd_warn(rbd_dev, "failed to unwatch: %d", ret);
3789

3790
	rbd_dev->watch_handle = NULL;
3791 3792
}

3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 3806 3807 3808 3809 3810 3811
static int rbd_register_watch(struct rbd_device *rbd_dev)
{
	int ret;

	mutex_lock(&rbd_dev->watch_mutex);
	rbd_assert(rbd_dev->watch_state == RBD_WATCH_STATE_UNREGISTERED);
	ret = __rbd_register_watch(rbd_dev);
	if (ret)
		goto out;

	rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED;
	rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id;

out:
	mutex_unlock(&rbd_dev->watch_mutex);
	return ret;
}

static void cancel_tasks_sync(struct rbd_device *rbd_dev)
3812
{
3813 3814 3815
	dout("%s rbd_dev %p\n", __func__, rbd_dev);

	cancel_delayed_work_sync(&rbd_dev->watch_dwork);
3816 3817 3818 3819
	cancel_work_sync(&rbd_dev->acquired_lock_work);
	cancel_work_sync(&rbd_dev->released_lock_work);
	cancel_delayed_work_sync(&rbd_dev->lock_dwork);
	cancel_work_sync(&rbd_dev->unlock_work);
3820 3821 3822 3823
}

static void rbd_unregister_watch(struct rbd_device *rbd_dev)
{
3824
	WARN_ON(waitqueue_active(&rbd_dev->lock_waitq));
3825 3826 3827 3828 3829 3830 3831
	cancel_tasks_sync(rbd_dev);

	mutex_lock(&rbd_dev->watch_mutex);
	if (rbd_dev->watch_state == RBD_WATCH_STATE_REGISTERED)
		__rbd_unregister_watch(rbd_dev);
	rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED;
	mutex_unlock(&rbd_dev->watch_mutex);
I
Ilya Dryomov 已提交
3832 3833

	ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc);
3834 3835
}

3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864
/*
 * lock_rwsem must be held for write
 */
static void rbd_reacquire_lock(struct rbd_device *rbd_dev)
{
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	char cookie[32];
	int ret;

	WARN_ON(rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED);

	format_lock_cookie(rbd_dev, cookie);
	ret = ceph_cls_set_cookie(osdc, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, RBD_LOCK_NAME,
				  CEPH_CLS_LOCK_EXCLUSIVE, rbd_dev->lock_cookie,
				  RBD_LOCK_TAG, cookie);
	if (ret) {
		if (ret != -EOPNOTSUPP)
			rbd_warn(rbd_dev, "failed to update lock cookie: %d",
				 ret);

		/*
		 * Lock cookie cannot be updated on older OSDs, so do
		 * a manual release and queue an acquire.
		 */
		if (rbd_release_lock(rbd_dev))
			queue_delayed_work(rbd_dev->task_wq,
					   &rbd_dev->lock_dwork, 0);
	} else {
3865
		__rbd_lock(rbd_dev, cookie);
3866 3867 3868
	}
}

3869 3870 3871 3872 3873 3874 3875 3876 3877
static void rbd_reregister_watch(struct work_struct *work)
{
	struct rbd_device *rbd_dev = container_of(to_delayed_work(work),
					    struct rbd_device, watch_dwork);
	int ret;

	dout("%s rbd_dev %p\n", __func__, rbd_dev);

	mutex_lock(&rbd_dev->watch_mutex);
3878 3879
	if (rbd_dev->watch_state != RBD_WATCH_STATE_ERROR) {
		mutex_unlock(&rbd_dev->watch_mutex);
3880
		return;
3881
	}
3882 3883 3884 3885

	ret = __rbd_register_watch(rbd_dev);
	if (ret) {
		rbd_warn(rbd_dev, "failed to reregister watch: %d", ret);
3886
		if (ret == -EBLACKLISTED || ret == -ENOENT) {
3887
			set_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags);
3888
			wake_requests(rbd_dev, true);
3889
		} else {
3890 3891 3892
			queue_delayed_work(rbd_dev->task_wq,
					   &rbd_dev->watch_dwork,
					   RBD_RETRY_DELAY);
3893 3894
		}
		mutex_unlock(&rbd_dev->watch_mutex);
3895
		return;
3896 3897 3898 3899 3900 3901
	}

	rbd_dev->watch_state = RBD_WATCH_STATE_REGISTERED;
	rbd_dev->watch_cookie = rbd_dev->watch_handle->linger_id;
	mutex_unlock(&rbd_dev->watch_mutex);

3902 3903 3904 3905 3906
	down_write(&rbd_dev->lock_rwsem);
	if (rbd_dev->lock_state == RBD_LOCK_STATE_LOCKED)
		rbd_reacquire_lock(rbd_dev);
	up_write(&rbd_dev->lock_rwsem);

3907 3908 3909 3910 3911
	ret = rbd_dev_refresh(rbd_dev);
	if (ret)
		rbd_warn(rbd_dev, "reregisteration refresh failed: %d", ret);
}

3912
/*
3913 3914
 * Synchronous osd object method call.  Returns the number of bytes
 * returned in the outbound buffer, or a negative error code.
3915 3916
 */
static int rbd_obj_method_sync(struct rbd_device *rbd_dev,
3917 3918
			     struct ceph_object_id *oid,
			     struct ceph_object_locator *oloc,
3919
			     const char *method_name,
3920
			     const void *outbound,
3921
			     size_t outbound_size,
3922
			     void *inbound,
3923
			     size_t inbound_size)
3924
{
3925 3926 3927
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	struct page *req_page = NULL;
	struct page *reply_page;
3928 3929 3930
	int ret;

	/*
3931 3932 3933 3934 3935
	 * Method calls are ultimately read operations.  The result
	 * should placed into the inbound buffer provided.  They
	 * also supply outbound data--parameters for the object
	 * method.  Currently if this is present it will be a
	 * snapshot id.
3936
	 */
3937 3938 3939
	if (outbound) {
		if (outbound_size > PAGE_SIZE)
			return -E2BIG;
3940

3941 3942 3943
		req_page = alloc_page(GFP_KERNEL);
		if (!req_page)
			return -ENOMEM;
3944

3945
		memcpy(page_address(req_page), outbound, outbound_size);
3946
	}
3947

3948 3949 3950 3951 3952 3953
	reply_page = alloc_page(GFP_KERNEL);
	if (!reply_page) {
		if (req_page)
			__free_page(req_page);
		return -ENOMEM;
	}
3954

3955 3956 3957 3958 3959 3960 3961
	ret = ceph_osdc_call(osdc, oid, oloc, RBD_DRV_NAME, method_name,
			     CEPH_OSD_FLAG_READ, req_page, outbound_size,
			     reply_page, &inbound_size);
	if (!ret) {
		memcpy(inbound, page_address(reply_page), inbound_size);
		ret = inbound_size;
	}
3962

3963 3964 3965
	if (req_page)
		__free_page(req_page);
	__free_page(reply_page);
3966 3967 3968
	return ret;
}

3969 3970 3971 3972 3973 3974 3975 3976 3977 3978 3979 3980 3981 3982 3983 3984 3985 3986 3987
/*
 * lock_rwsem must be held for read
 */
static void rbd_wait_state_locked(struct rbd_device *rbd_dev)
{
	DEFINE_WAIT(wait);

	do {
		/*
		 * Note the use of mod_delayed_work() in rbd_acquire_lock()
		 * and cancel_delayed_work() in wake_requests().
		 */
		dout("%s rbd_dev %p queueing lock_dwork\n", __func__, rbd_dev);
		queue_delayed_work(rbd_dev->task_wq, &rbd_dev->lock_dwork, 0);
		prepare_to_wait_exclusive(&rbd_dev->lock_waitq, &wait,
					  TASK_UNINTERRUPTIBLE);
		up_read(&rbd_dev->lock_rwsem);
		schedule();
		down_read(&rbd_dev->lock_rwsem);
3988 3989 3990
	} while (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED &&
		 !test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags));

3991 3992 3993
	finish_wait(&rbd_dev->lock_waitq, &wait);
}

C
Christoph Hellwig 已提交
3994
static void rbd_queue_workfn(struct work_struct *work)
A
Alex Elder 已提交
3995
{
C
Christoph Hellwig 已提交
3996 3997
	struct request *rq = blk_mq_rq_from_pdu(work);
	struct rbd_device *rbd_dev = rq->q->queuedata;
I
Ilya Dryomov 已提交
3998
	struct rbd_img_request *img_request;
3999
	struct ceph_snap_context *snapc = NULL;
I
Ilya Dryomov 已提交
4000 4001
	u64 offset = (u64)blk_rq_pos(rq) << SECTOR_SHIFT;
	u64 length = blk_rq_bytes(rq);
G
Guangliang Zhao 已提交
4002
	enum obj_operation_type op_type;
4003
	u64 mapping_size;
I
Ilya Dryomov 已提交
4004
	bool must_be_locked;
A
Alex Elder 已提交
4005 4006
	int result;

4007 4008
	switch (req_op(rq)) {
	case REQ_OP_DISCARD:
4009
	case REQ_OP_WRITE_ZEROES:
4010
		op_type = OBJ_OP_DISCARD;
4011 4012
		break;
	case REQ_OP_WRITE:
G
Guangliang Zhao 已提交
4013
		op_type = OBJ_OP_WRITE;
4014 4015
		break;
	case REQ_OP_READ:
G
Guangliang Zhao 已提交
4016
		op_type = OBJ_OP_READ;
4017 4018 4019 4020 4021 4022
		break;
	default:
		dout("%s: non-fs request type %d\n", __func__, req_op(rq));
		result = -EIO;
		goto err;
	}
G
Guangliang Zhao 已提交
4023

I
Ilya Dryomov 已提交
4024
	/* Ignore/skip any zero-length requests */
A
Alex Elder 已提交
4025

I
Ilya Dryomov 已提交
4026 4027 4028 4029 4030
	if (!length) {
		dout("%s: zero-length request\n", __func__);
		result = 0;
		goto err_rq;
	}
A
Alex Elder 已提交
4031

4032 4033
	rbd_assert(op_type == OBJ_OP_READ ||
		   rbd_dev->spec->snap_id == CEPH_NOSNAP);
A
Alex Elder 已提交
4034

I
Ilya Dryomov 已提交
4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046
	/*
	 * Quit early if the mapped snapshot no longer exists.  It's
	 * still possible the snapshot will have disappeared by the
	 * time our request arrives at the osd, but there's no sense in
	 * sending it if we already know.
	 */
	if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags)) {
		dout("request for non-existent snapshot");
		rbd_assert(rbd_dev->spec->snap_id != CEPH_NOSNAP);
		result = -ENXIO;
		goto err_rq;
	}
A
Alex Elder 已提交
4047

I
Ilya Dryomov 已提交
4048 4049 4050 4051 4052 4053
	if (offset && length > U64_MAX - offset + 1) {
		rbd_warn(rbd_dev, "bad request range (%llu~%llu)", offset,
			 length);
		result = -EINVAL;
		goto err_rq;	/* Shouldn't happen */
	}
A
Alex Elder 已提交
4054

C
Christoph Hellwig 已提交
4055 4056
	blk_mq_start_request(rq);

4057 4058
	down_read(&rbd_dev->header_rwsem);
	mapping_size = rbd_dev->mapping.size;
G
Guangliang Zhao 已提交
4059
	if (op_type != OBJ_OP_READ) {
4060 4061 4062 4063 4064 4065
		snapc = rbd_dev->header.snapc;
		ceph_get_snap_context(snapc);
	}
	up_read(&rbd_dev->header_rwsem);

	if (offset + length > mapping_size) {
I
Ilya Dryomov 已提交
4066
		rbd_warn(rbd_dev, "beyond EOD (%llu~%llu > %llu)", offset,
4067
			 length, mapping_size);
I
Ilya Dryomov 已提交
4068 4069 4070
		result = -EIO;
		goto err_rq;
	}
A
Alex Elder 已提交
4071

I
Ilya Dryomov 已提交
4072 4073 4074
	must_be_locked =
	    (rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK) &&
	    (op_type != OBJ_OP_READ || rbd_dev->opts->lock_on_read);
4075 4076
	if (must_be_locked) {
		down_read(&rbd_dev->lock_rwsem);
4077
		if (rbd_dev->lock_state != RBD_LOCK_STATE_LOCKED &&
I
Ilya Dryomov 已提交
4078 4079 4080 4081 4082 4083
		    !test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) {
			if (rbd_dev->opts->exclusive) {
				rbd_warn(rbd_dev, "exclusive lock required");
				result = -EROFS;
				goto err_unlock;
			}
4084
			rbd_wait_state_locked(rbd_dev);
I
Ilya Dryomov 已提交
4085
		}
4086 4087 4088 4089
		if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) {
			result = -EBLACKLISTED;
			goto err_unlock;
		}
4090 4091
	}

G
Guangliang Zhao 已提交
4092
	img_request = rbd_img_request_create(rbd_dev, offset, length, op_type,
4093
					     snapc);
I
Ilya Dryomov 已提交
4094 4095
	if (!img_request) {
		result = -ENOMEM;
4096
		goto err_unlock;
I
Ilya Dryomov 已提交
4097 4098
	}
	img_request->rq = rq;
4099
	snapc = NULL; /* img_request consumes a ref */
A
Alex Elder 已提交
4100

4101 4102 4103 4104 4105 4106
	if (op_type == OBJ_OP_DISCARD)
		result = rbd_img_request_fill(img_request, OBJ_REQUEST_NODATA,
					      NULL);
	else
		result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO,
					      rq->bio);
I
Ilya Dryomov 已提交
4107 4108
	if (result)
		goto err_img_request;
A
Alex Elder 已提交
4109

I
Ilya Dryomov 已提交
4110 4111 4112
	result = rbd_img_request_submit(img_request);
	if (result)
		goto err_img_request;
A
Alex Elder 已提交
4113

4114 4115
	if (must_be_locked)
		up_read(&rbd_dev->lock_rwsem);
I
Ilya Dryomov 已提交
4116
	return;
A
Alex Elder 已提交
4117

I
Ilya Dryomov 已提交
4118 4119
err_img_request:
	rbd_img_request_put(img_request);
4120 4121 4122
err_unlock:
	if (must_be_locked)
		up_read(&rbd_dev->lock_rwsem);
I
Ilya Dryomov 已提交
4123 4124 4125
err_rq:
	if (result)
		rbd_warn(rbd_dev, "%s %llx at %llx result %d",
G
Guangliang Zhao 已提交
4126
			 obj_op_name(op_type), length, offset, result);
4127
	ceph_put_snap_context(snapc);
C
Christoph Hellwig 已提交
4128
err:
4129
	blk_mq_end_request(rq, errno_to_blk_status(result));
I
Ilya Dryomov 已提交
4130
}
A
Alex Elder 已提交
4131

4132
static blk_status_t rbd_queue_rq(struct blk_mq_hw_ctx *hctx,
C
Christoph Hellwig 已提交
4133
		const struct blk_mq_queue_data *bd)
I
Ilya Dryomov 已提交
4134
{
C
Christoph Hellwig 已提交
4135 4136
	struct request *rq = bd->rq;
	struct work_struct *work = blk_mq_rq_to_pdu(rq);
A
Alex Elder 已提交
4137

C
Christoph Hellwig 已提交
4138
	queue_work(rbd_wq, work);
4139
	return BLK_STS_OK;
A
Alex Elder 已提交
4140 4141
}

4142 4143
static void rbd_free_disk(struct rbd_device *rbd_dev)
{
4144 4145 4146
	blk_cleanup_queue(rbd_dev->disk->queue);
	blk_mq_free_tag_set(&rbd_dev->tag_set);
	put_disk(rbd_dev->disk);
4147
	rbd_dev->disk = NULL;
4148 4149
}

4150
static int rbd_obj_read_sync(struct rbd_device *rbd_dev,
4151 4152 4153
			     struct ceph_object_id *oid,
			     struct ceph_object_locator *oloc,
			     void *buf, int buf_len)
4154 4155

{
4156 4157 4158 4159
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	struct ceph_osd_request *req;
	struct page **pages;
	int num_pages = calc_pages_for(0, buf_len);
4160 4161
	int ret;

4162 4163 4164
	req = ceph_osdc_alloc_request(osdc, NULL, 1, false, GFP_KERNEL);
	if (!req)
		return -ENOMEM;
4165

4166 4167 4168
	ceph_oid_copy(&req->r_base_oid, oid);
	ceph_oloc_copy(&req->r_base_oloc, oloc);
	req->r_flags = CEPH_OSD_FLAG_READ;
A
Alex Elder 已提交
4169

4170
	ret = ceph_osdc_alloc_messages(req, GFP_KERNEL);
4171
	if (ret)
4172
		goto out_req;
4173

4174 4175 4176 4177 4178
	pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
	if (IS_ERR(pages)) {
		ret = PTR_ERR(pages);
		goto out_req;
	}
4179

4180 4181 4182 4183 4184 4185 4186 4187
	osd_req_op_extent_init(req, 0, CEPH_OSD_OP_READ, 0, buf_len, 0, 0);
	osd_req_op_extent_osd_data_pages(req, 0, pages, buf_len, 0, false,
					 true);

	ceph_osdc_start_request(osdc, req, false);
	ret = ceph_osdc_wait_request(osdc, req);
	if (ret >= 0)
		ceph_copy_from_page_vector(pages, buf, 0, ret);
4188

4189 4190
out_req:
	ceph_osdc_put_request(req);
4191 4192 4193
	return ret;
}

4194
/*
A
Alex Elder 已提交
4195 4196 4197
 * Read the complete header for the given rbd device.  On successful
 * return, the rbd_dev->header field will contain up-to-date
 * information about the image.
4198
 */
4199
static int rbd_dev_v1_header_info(struct rbd_device *rbd_dev)
4200
{
4201
	struct rbd_image_header_ondisk *ondisk = NULL;
4202
	u32 snap_count = 0;
4203 4204 4205
	u64 names_size = 0;
	u32 want_count;
	int ret;
4206

A
Alex Elder 已提交
4207
	/*
4208 4209 4210 4211 4212
	 * The complete header will include an array of its 64-bit
	 * snapshot ids, followed by the names of those snapshots as
	 * a contiguous block of NUL-terminated strings.  Note that
	 * the number of snapshots could change by the time we read
	 * it in, in which case we re-read it.
A
Alex Elder 已提交
4213
	 */
4214 4215 4216 4217 4218 4219 4220 4221 4222 4223
	do {
		size_t size;

		kfree(ondisk);

		size = sizeof (*ondisk);
		size += snap_count * sizeof (struct rbd_image_snap_ondisk);
		size += names_size;
		ondisk = kmalloc(size, GFP_KERNEL);
		if (!ondisk)
A
Alex Elder 已提交
4224
			return -ENOMEM;
4225

4226 4227
		ret = rbd_obj_read_sync(rbd_dev, &rbd_dev->header_oid,
					&rbd_dev->header_oloc, ondisk, size);
4228
		if (ret < 0)
A
Alex Elder 已提交
4229
			goto out;
A
Alex Elder 已提交
4230
		if ((size_t)ret < size) {
4231
			ret = -ENXIO;
A
Alex Elder 已提交
4232 4233
			rbd_warn(rbd_dev, "short header read (want %zd got %d)",
				size, ret);
A
Alex Elder 已提交
4234
			goto out;
4235 4236 4237
		}
		if (!rbd_dev_ondisk_valid(ondisk)) {
			ret = -ENXIO;
A
Alex Elder 已提交
4238
			rbd_warn(rbd_dev, "invalid header");
A
Alex Elder 已提交
4239
			goto out;
4240
		}
4241

4242 4243 4244 4245
		names_size = le64_to_cpu(ondisk->snap_names_len);
		want_count = snap_count;
		snap_count = le32_to_cpu(ondisk->snap_count);
	} while (snap_count != want_count);
A
Alex Elder 已提交
4246

A
Alex Elder 已提交
4247 4248
	ret = rbd_header_from_disk(rbd_dev, ondisk);
out:
4249 4250 4251
	kfree(ondisk);

	return ret;
4252 4253
}

4254 4255 4256 4257 4258 4259 4260 4261 4262 4263 4264 4265 4266 4267 4268 4269 4270 4271 4272
/*
 * Clear the rbd device's EXISTS flag if the snapshot it's mapped to
 * has disappeared from the (just updated) snapshot context.
 */
static void rbd_exists_validate(struct rbd_device *rbd_dev)
{
	u64 snap_id;

	if (!test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags))
		return;

	snap_id = rbd_dev->spec->snap_id;
	if (snap_id == CEPH_NOSNAP)
		return;

	if (rbd_dev_snap_index(rbd_dev, snap_id) == BAD_SNAP_INDEX)
		clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
}

4273 4274 4275 4276 4277
static void rbd_dev_update_size(struct rbd_device *rbd_dev)
{
	sector_t size;

	/*
I
Ilya Dryomov 已提交
4278 4279 4280
	 * If EXISTS is not set, rbd_dev->disk may be NULL, so don't
	 * try to update its size.  If REMOVING is set, updating size
	 * is just useless work since the device can't be opened.
4281
	 */
I
Ilya Dryomov 已提交
4282 4283
	if (test_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags) &&
	    !test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) {
4284 4285 4286 4287 4288 4289 4290
		size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
		dout("setting size to %llu sectors", (unsigned long long)size);
		set_capacity(rbd_dev->disk, size);
		revalidate_disk(rbd_dev->disk);
	}
}

A
Alex Elder 已提交
4291
static int rbd_dev_refresh(struct rbd_device *rbd_dev)
A
Alex Elder 已提交
4292
{
4293
	u64 mapping_size;
A
Alex Elder 已提交
4294 4295
	int ret;

4296
	down_write(&rbd_dev->header_rwsem);
4297
	mapping_size = rbd_dev->mapping.size;
4298 4299

	ret = rbd_dev_header_info(rbd_dev);
4300
	if (ret)
4301
		goto out;
4302

4303 4304 4305 4306 4307 4308 4309
	/*
	 * If there is a parent, see if it has disappeared due to the
	 * mapped image getting flattened.
	 */
	if (rbd_dev->parent) {
		ret = rbd_dev_v2_parent_info(rbd_dev);
		if (ret)
4310
			goto out;
4311 4312
	}

4313
	if (rbd_dev->spec->snap_id == CEPH_NOSNAP) {
4314
		rbd_dev->mapping.size = rbd_dev->header.image_size;
4315 4316 4317 4318
	} else {
		/* validate mapped snapshot's EXISTS flag */
		rbd_exists_validate(rbd_dev);
	}
4319

4320
out:
4321
	up_write(&rbd_dev->header_rwsem);
4322
	if (!ret && mapping_size != rbd_dev->mapping.size)
4323
		rbd_dev_update_size(rbd_dev);
A
Alex Elder 已提交
4324

4325
	return ret;
A
Alex Elder 已提交
4326 4327
}

4328 4329
static int rbd_init_request(struct blk_mq_tag_set *set, struct request *rq,
		unsigned int hctx_idx, unsigned int numa_node)
C
Christoph Hellwig 已提交
4330 4331 4332 4333 4334 4335 4336
{
	struct work_struct *work = blk_mq_rq_to_pdu(rq);

	INIT_WORK(work, rbd_queue_workfn);
	return 0;
}

4337
static const struct blk_mq_ops rbd_mq_ops = {
C
Christoph Hellwig 已提交
4338 4339 4340 4341
	.queue_rq	= rbd_queue_rq,
	.init_request	= rbd_init_request,
};

4342 4343 4344 4345
static int rbd_init_disk(struct rbd_device *rbd_dev)
{
	struct gendisk *disk;
	struct request_queue *q;
A
Alex Elder 已提交
4346
	u64 segment_size;
C
Christoph Hellwig 已提交
4347
	int err;
4348 4349

	/* create gendisk info */
4350 4351 4352
	disk = alloc_disk(single_major ?
			  (1 << RBD_SINGLE_MAJOR_PART_SHIFT) :
			  RBD_MINORS_PER_MAJOR);
4353
	if (!disk)
A
Alex Elder 已提交
4354
		return -ENOMEM;
4355

A
Alex Elder 已提交
4356
	snprintf(disk->disk_name, sizeof(disk->disk_name), RBD_DRV_NAME "%d",
A
Alex Elder 已提交
4357
		 rbd_dev->dev_id);
4358
	disk->major = rbd_dev->major;
4359
	disk->first_minor = rbd_dev->minor;
4360 4361
	if (single_major)
		disk->flags |= GENHD_FL_EXT_DEVT;
4362 4363 4364
	disk->fops = &rbd_bd_ops;
	disk->private_data = rbd_dev;

C
Christoph Hellwig 已提交
4365 4366
	memset(&rbd_dev->tag_set, 0, sizeof(rbd_dev->tag_set));
	rbd_dev->tag_set.ops = &rbd_mq_ops;
I
Ilya Dryomov 已提交
4367
	rbd_dev->tag_set.queue_depth = rbd_dev->opts->queue_depth;
C
Christoph Hellwig 已提交
4368
	rbd_dev->tag_set.numa_node = NUMA_NO_NODE;
I
Ilya Dryomov 已提交
4369
	rbd_dev->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_SG_MERGE;
C
Christoph Hellwig 已提交
4370 4371 4372 4373 4374
	rbd_dev->tag_set.nr_hw_queues = 1;
	rbd_dev->tag_set.cmd_size = sizeof(struct work_struct);

	err = blk_mq_alloc_tag_set(&rbd_dev->tag_set);
	if (err)
4375
		goto out_disk;
4376

C
Christoph Hellwig 已提交
4377 4378 4379 4380 4381 4382
	q = blk_mq_init_queue(&rbd_dev->tag_set);
	if (IS_ERR(q)) {
		err = PTR_ERR(q);
		goto out_tag_set;
	}

4383 4384
	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q);
	/* QUEUE_FLAG_ADD_RANDOM is off by default for blk-mq */
A
Alex Elder 已提交
4385

4386
	/* set io sizes to object size */
A
Alex Elder 已提交
4387 4388
	segment_size = rbd_obj_bytes(&rbd_dev->header);
	blk_queue_max_hw_sectors(q, segment_size / SECTOR_SIZE);
I
Ilya Dryomov 已提交
4389
	q->limits.max_sectors = queue_max_hw_sectors(q);
I
Ilya Dryomov 已提交
4390
	blk_queue_max_segments(q, segment_size / SECTOR_SIZE);
A
Alex Elder 已提交
4391 4392 4393
	blk_queue_max_segment_size(q, segment_size);
	blk_queue_io_min(q, segment_size);
	blk_queue_io_opt(q, segment_size);
4394

4395 4396 4397
	/* enable the discard support */
	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
	q->limits.discard_granularity = segment_size;
4398
	blk_queue_max_discard_sectors(q, segment_size / SECTOR_SIZE);
4399
	blk_queue_max_write_zeroes_sectors(q, segment_size / SECTOR_SIZE);
4400

4401
	if (!ceph_test_opt(rbd_dev->rbd_client->client, NOCRC))
4402
		q->backing_dev_info->capabilities |= BDI_CAP_STABLE_WRITES;
4403

4404 4405 4406 4407 4408
	/*
	 * disk_release() expects a queue ref from add_disk() and will
	 * put it.  Hold an extra ref until add_disk() is called.
	 */
	WARN_ON(!blk_get_queue(q));
4409 4410 4411 4412 4413 4414
	disk->queue = q;
	q->queuedata = rbd_dev;

	rbd_dev->disk = disk;

	return 0;
C
Christoph Hellwig 已提交
4415 4416
out_tag_set:
	blk_mq_free_tag_set(&rbd_dev->tag_set);
4417 4418
out_disk:
	put_disk(disk);
C
Christoph Hellwig 已提交
4419
	return err;
4420 4421
}

4422 4423 4424 4425
/*
  sysfs
*/

A
Alex Elder 已提交
4426 4427 4428 4429 4430
static struct rbd_device *dev_to_rbd_dev(struct device *dev)
{
	return container_of(dev, struct rbd_device, dev);
}

4431 4432 4433
static ssize_t rbd_size_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
A
Alex Elder 已提交
4434
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4435

A
Alex Elder 已提交
4436 4437
	return sprintf(buf, "%llu\n",
		(unsigned long long)rbd_dev->mapping.size);
4438 4439
}

A
Alex Elder 已提交
4440 4441 4442 4443 4444 4445 4446 4447 4448 4449
/*
 * Note this shows the features for whatever's mapped, which is not
 * necessarily the base image.
 */
static ssize_t rbd_features_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

	return sprintf(buf, "0x%016llx\n",
A
Alex Elder 已提交
4450
			(unsigned long long)rbd_dev->mapping.features);
A
Alex Elder 已提交
4451 4452
}

4453 4454 4455
static ssize_t rbd_major_show(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
A
Alex Elder 已提交
4456
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4457

A
Alex Elder 已提交
4458 4459 4460 4461
	if (rbd_dev->major)
		return sprintf(buf, "%d\n", rbd_dev->major);

	return sprintf(buf, "(none)\n");
4462 4463 4464 4465 4466 4467
}

static ssize_t rbd_minor_show(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
A
Alex Elder 已提交
4468

4469
	return sprintf(buf, "%d\n", rbd_dev->minor);
4470 4471
}

4472 4473 4474 4475 4476 4477 4478 4479 4480 4481 4482
static ssize_t rbd_client_addr_show(struct device *dev,
				    struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
	struct ceph_entity_addr *client_addr =
	    ceph_client_addr(rbd_dev->rbd_client->client);

	return sprintf(buf, "%pISpc/%u\n", &client_addr->in_addr,
		       le32_to_cpu(client_addr->nonce));
}

4483 4484
static ssize_t rbd_client_id_show(struct device *dev,
				  struct device_attribute *attr, char *buf)
4485
{
A
Alex Elder 已提交
4486
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4487

4488
	return sprintf(buf, "client%lld\n",
4489
		       ceph_client_gid(rbd_dev->rbd_client->client));
4490 4491
}

4492 4493 4494 4495 4496 4497 4498 4499
static ssize_t rbd_cluster_fsid_show(struct device *dev,
				     struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

	return sprintf(buf, "%pU\n", &rbd_dev->rbd_client->client->fsid);
}

4500 4501 4502 4503 4504 4505
static ssize_t rbd_config_info_show(struct device *dev,
				    struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

	return sprintf(buf, "%s\n", rbd_dev->config_info);
4506 4507
}

4508 4509
static ssize_t rbd_pool_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
4510
{
A
Alex Elder 已提交
4511
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4512

4513
	return sprintf(buf, "%s\n", rbd_dev->spec->pool_name);
4514 4515
}

4516 4517 4518 4519 4520
static ssize_t rbd_pool_id_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

4521
	return sprintf(buf, "%llu\n",
A
Alex Elder 已提交
4522
			(unsigned long long) rbd_dev->spec->pool_id);
4523 4524
}

4525 4526 4527
static ssize_t rbd_name_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
A
Alex Elder 已提交
4528
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4529

A
Alex Elder 已提交
4530 4531 4532 4533
	if (rbd_dev->spec->image_name)
		return sprintf(buf, "%s\n", rbd_dev->spec->image_name);

	return sprintf(buf, "(unknown)\n");
4534 4535
}

A
Alex Elder 已提交
4536 4537 4538 4539 4540
static ssize_t rbd_image_id_show(struct device *dev,
			     struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

4541
	return sprintf(buf, "%s\n", rbd_dev->spec->image_id);
A
Alex Elder 已提交
4542 4543
}

A
Alex Elder 已提交
4544 4545 4546 4547
/*
 * Shows the name of the currently-mapped snapshot (or
 * RBD_SNAP_HEAD_NAME for the base image).
 */
4548 4549 4550 4551
static ssize_t rbd_snap_show(struct device *dev,
			     struct device_attribute *attr,
			     char *buf)
{
A
Alex Elder 已提交
4552
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4553

4554
	return sprintf(buf, "%s\n", rbd_dev->spec->snap_name);
4555 4556
}

4557 4558 4559 4560 4561 4562 4563 4564
static ssize_t rbd_snap_id_show(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);

	return sprintf(buf, "%llu\n", rbd_dev->spec->snap_id);
}

4565
/*
4566 4567 4568
 * For a v2 image, shows the chain of parent images, separated by empty
 * lines.  For v1 images or if there is no parent, shows "(no parent
 * image)".
4569 4570
 */
static ssize_t rbd_parent_show(struct device *dev,
4571 4572
			       struct device_attribute *attr,
			       char *buf)
4573 4574
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4575
	ssize_t count = 0;
4576

4577
	if (!rbd_dev->parent)
4578 4579
		return sprintf(buf, "(no parent image)\n");

4580 4581 4582 4583 4584 4585 4586 4587 4588 4589 4590 4591 4592 4593 4594 4595
	for ( ; rbd_dev->parent; rbd_dev = rbd_dev->parent) {
		struct rbd_spec *spec = rbd_dev->parent_spec;

		count += sprintf(&buf[count], "%s"
			    "pool_id %llu\npool_name %s\n"
			    "image_id %s\nimage_name %s\n"
			    "snap_id %llu\nsnap_name %s\n"
			    "overlap %llu\n",
			    !count ? "" : "\n", /* first? */
			    spec->pool_id, spec->pool_name,
			    spec->image_id, spec->image_name ?: "(unknown)",
			    spec->snap_id, spec->snap_name,
			    rbd_dev->parent_overlap);
	}

	return count;
4596 4597
}

4598 4599 4600 4601 4602
static ssize_t rbd_image_refresh(struct device *dev,
				 struct device_attribute *attr,
				 const char *buf,
				 size_t size)
{
A
Alex Elder 已提交
4603
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
4604
	int ret;
4605

A
Alex Elder 已提交
4606
	ret = rbd_dev_refresh(rbd_dev);
4607
	if (ret)
4608
		return ret;
4609

4610
	return size;
4611
}
4612

4613
static DEVICE_ATTR(size, S_IRUGO, rbd_size_show, NULL);
A
Alex Elder 已提交
4614
static DEVICE_ATTR(features, S_IRUGO, rbd_features_show, NULL);
4615
static DEVICE_ATTR(major, S_IRUGO, rbd_major_show, NULL);
4616
static DEVICE_ATTR(minor, S_IRUGO, rbd_minor_show, NULL);
4617
static DEVICE_ATTR(client_addr, S_IRUGO, rbd_client_addr_show, NULL);
4618
static DEVICE_ATTR(client_id, S_IRUGO, rbd_client_id_show, NULL);
4619
static DEVICE_ATTR(cluster_fsid, S_IRUGO, rbd_cluster_fsid_show, NULL);
4620
static DEVICE_ATTR(config_info, S_IRUSR, rbd_config_info_show, NULL);
4621
static DEVICE_ATTR(pool, S_IRUGO, rbd_pool_show, NULL);
4622
static DEVICE_ATTR(pool_id, S_IRUGO, rbd_pool_id_show, NULL);
4623
static DEVICE_ATTR(name, S_IRUGO, rbd_name_show, NULL);
A
Alex Elder 已提交
4624
static DEVICE_ATTR(image_id, S_IRUGO, rbd_image_id_show, NULL);
4625 4626
static DEVICE_ATTR(refresh, S_IWUSR, NULL, rbd_image_refresh);
static DEVICE_ATTR(current_snap, S_IRUGO, rbd_snap_show, NULL);
4627
static DEVICE_ATTR(snap_id, S_IRUGO, rbd_snap_id_show, NULL);
4628
static DEVICE_ATTR(parent, S_IRUGO, rbd_parent_show, NULL);
4629 4630 4631

static struct attribute *rbd_attrs[] = {
	&dev_attr_size.attr,
A
Alex Elder 已提交
4632
	&dev_attr_features.attr,
4633
	&dev_attr_major.attr,
4634
	&dev_attr_minor.attr,
4635
	&dev_attr_client_addr.attr,
4636
	&dev_attr_client_id.attr,
4637
	&dev_attr_cluster_fsid.attr,
4638
	&dev_attr_config_info.attr,
4639
	&dev_attr_pool.attr,
4640
	&dev_attr_pool_id.attr,
4641
	&dev_attr_name.attr,
A
Alex Elder 已提交
4642
	&dev_attr_image_id.attr,
4643
	&dev_attr_current_snap.attr,
4644
	&dev_attr_snap_id.attr,
4645
	&dev_attr_parent.attr,
4646 4647 4648 4649 4650 4651 4652 4653 4654 4655 4656 4657 4658
	&dev_attr_refresh.attr,
	NULL
};

static struct attribute_group rbd_attr_group = {
	.attrs = rbd_attrs,
};

static const struct attribute_group *rbd_attr_groups[] = {
	&rbd_attr_group,
	NULL
};

4659
static void rbd_dev_release(struct device *dev);
4660

4661
static const struct device_type rbd_device_type = {
4662 4663
	.name		= "rbd",
	.groups		= rbd_attr_groups,
4664
	.release	= rbd_dev_release,
4665 4666
};

4667 4668 4669 4670 4671 4672 4673 4674 4675 4676 4677 4678 4679 4680 4681 4682 4683 4684 4685 4686 4687
static struct rbd_spec *rbd_spec_get(struct rbd_spec *spec)
{
	kref_get(&spec->kref);

	return spec;
}

static void rbd_spec_free(struct kref *kref);
static void rbd_spec_put(struct rbd_spec *spec)
{
	if (spec)
		kref_put(&spec->kref, rbd_spec_free);
}

static struct rbd_spec *rbd_spec_alloc(void)
{
	struct rbd_spec *spec;

	spec = kzalloc(sizeof (*spec), GFP_KERNEL);
	if (!spec)
		return NULL;
4688 4689 4690

	spec->pool_id = CEPH_NOPOOL;
	spec->snap_id = CEPH_NOSNAP;
4691 4692 4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704 4705 4706
	kref_init(&spec->kref);

	return spec;
}

static void rbd_spec_free(struct kref *kref)
{
	struct rbd_spec *spec = container_of(kref, struct rbd_spec, kref);

	kfree(spec->pool_name);
	kfree(spec->image_id);
	kfree(spec->image_name);
	kfree(spec->snap_name);
	kfree(spec);
}

4707
static void rbd_dev_free(struct rbd_device *rbd_dev)
4708
{
4709
	WARN_ON(rbd_dev->watch_state != RBD_WATCH_STATE_UNREGISTERED);
4710
	WARN_ON(rbd_dev->lock_state != RBD_LOCK_STATE_UNLOCKED);
4711

4712
	ceph_oid_destroy(&rbd_dev->header_oid);
4713
	ceph_oloc_destroy(&rbd_dev->header_oloc);
4714
	kfree(rbd_dev->config_info);
4715

4716 4717 4718 4719
	rbd_put_client(rbd_dev->rbd_client);
	rbd_spec_put(rbd_dev->spec);
	kfree(rbd_dev->opts);
	kfree(rbd_dev);
4720 4721 4722 4723 4724 4725 4726 4727 4728 4729 4730 4731 4732
}

static void rbd_dev_release(struct device *dev)
{
	struct rbd_device *rbd_dev = dev_to_rbd_dev(dev);
	bool need_put = !!rbd_dev->opts;

	if (need_put) {
		destroy_workqueue(rbd_dev->task_wq);
		ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id);
	}

	rbd_dev_free(rbd_dev);
4733 4734 4735 4736 4737 4738 4739 4740 4741 4742

	/*
	 * This is racy, but way better than putting module outside of
	 * the release callback.  The race window is pretty small, so
	 * doing something similar to dm (dm-builtin.c) is overkill.
	 */
	if (need_put)
		module_put(THIS_MODULE);
}

4743 4744
static struct rbd_device *__rbd_dev_create(struct rbd_client *rbdc,
					   struct rbd_spec *spec)
4745 4746 4747
{
	struct rbd_device *rbd_dev;

4748
	rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL);
4749 4750 4751 4752 4753 4754 4755
	if (!rbd_dev)
		return NULL;

	spin_lock_init(&rbd_dev->lock);
	INIT_LIST_HEAD(&rbd_dev->node);
	init_rwsem(&rbd_dev->header_rwsem);

4756
	rbd_dev->header.data_pool_id = CEPH_NOPOOL;
4757
	ceph_oid_init(&rbd_dev->header_oid);
4758
	rbd_dev->header_oloc.pool = spec->pool_id;
4759

4760 4761 4762 4763
	mutex_init(&rbd_dev->watch_mutex);
	rbd_dev->watch_state = RBD_WATCH_STATE_UNREGISTERED;
	INIT_DELAYED_WORK(&rbd_dev->watch_dwork, rbd_reregister_watch);

4764 4765 4766 4767 4768 4769 4770 4771
	init_rwsem(&rbd_dev->lock_rwsem);
	rbd_dev->lock_state = RBD_LOCK_STATE_UNLOCKED;
	INIT_WORK(&rbd_dev->acquired_lock_work, rbd_notify_acquired_lock);
	INIT_WORK(&rbd_dev->released_lock_work, rbd_notify_released_lock);
	INIT_DELAYED_WORK(&rbd_dev->lock_dwork, rbd_acquire_lock);
	INIT_WORK(&rbd_dev->unlock_work, rbd_release_lock_work);
	init_waitqueue_head(&rbd_dev->lock_waitq);

4772 4773 4774 4775 4776
	rbd_dev->dev.bus = &rbd_bus_type;
	rbd_dev->dev.type = &rbd_device_type;
	rbd_dev->dev.parent = &rbd_root_dev;
	device_initialize(&rbd_dev->dev);

4777
	rbd_dev->rbd_client = rbdc;
4778
	rbd_dev->spec = spec;
4779

4780 4781 4782 4783 4784 4785 4786 4787 4788 4789 4790 4791 4792 4793 4794 4795 4796 4797 4798 4799 4800 4801 4802 4803 4804 4805 4806 4807 4808 4809
	return rbd_dev;
}

/*
 * Create a mapping rbd_dev.
 */
static struct rbd_device *rbd_dev_create(struct rbd_client *rbdc,
					 struct rbd_spec *spec,
					 struct rbd_options *opts)
{
	struct rbd_device *rbd_dev;

	rbd_dev = __rbd_dev_create(rbdc, spec);
	if (!rbd_dev)
		return NULL;

	rbd_dev->opts = opts;

	/* get an id and fill in device name */
	rbd_dev->dev_id = ida_simple_get(&rbd_dev_id_ida, 0,
					 minor_to_rbd_dev_id(1 << MINORBITS),
					 GFP_KERNEL);
	if (rbd_dev->dev_id < 0)
		goto fail_rbd_dev;

	sprintf(rbd_dev->name, RBD_DRV_NAME "%d", rbd_dev->dev_id);
	rbd_dev->task_wq = alloc_ordered_workqueue("%s-tasks", WQ_MEM_RECLAIM,
						   rbd_dev->name);
	if (!rbd_dev->task_wq)
		goto fail_dev_id;
4810

4811 4812
	/* we have a ref from do_rbd_add() */
	__module_get(THIS_MODULE);
4813

4814
	dout("%s rbd_dev %p dev_id %d\n", __func__, rbd_dev, rbd_dev->dev_id);
4815
	return rbd_dev;
4816 4817 4818 4819 4820 4821

fail_dev_id:
	ida_simple_remove(&rbd_dev_id_ida, rbd_dev->dev_id);
fail_rbd_dev:
	rbd_dev_free(rbd_dev);
	return NULL;
4822 4823 4824 4825
}

static void rbd_dev_destroy(struct rbd_device *rbd_dev)
{
4826 4827
	if (rbd_dev)
		put_device(&rbd_dev->dev);
4828 4829
}

4830 4831 4832 4833 4834 4835 4836 4837 4838 4839 4840 4841 4842 4843 4844
/*
 * Get the size and object order for an image snapshot, or if
 * snap_id is CEPH_NOSNAP, gets this information for the base
 * image.
 */
static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id,
				u8 *order, u64 *snap_size)
{
	__le64 snapid = cpu_to_le64(snap_id);
	int ret;
	struct {
		u8 order;
		__le64 size;
	} __attribute__ ((packed)) size_buf = { 0 };

4845 4846 4847 4848
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_size",
				  &snapid, sizeof(snapid),
				  &size_buf, sizeof(size_buf));
4849
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4850 4851
	if (ret < 0)
		return ret;
4852 4853
	if (ret < sizeof (size_buf))
		return -ERANGE;
4854

J
Josh Durgin 已提交
4855
	if (order) {
4856
		*order = size_buf.order;
J
Josh Durgin 已提交
4857 4858
		dout("  order %u", (unsigned int)*order);
	}
4859 4860
	*snap_size = le64_to_cpu(size_buf.size);

J
Josh Durgin 已提交
4861 4862
	dout("  snap_id 0x%016llx snap_size = %llu\n",
		(unsigned long long)snap_id,
4863
		(unsigned long long)*snap_size);
4864 4865 4866 4867 4868 4869 4870 4871 4872 4873 4874

	return 0;
}

static int rbd_dev_v2_image_size(struct rbd_device *rbd_dev)
{
	return _rbd_dev_v2_snap_size(rbd_dev, CEPH_NOSNAP,
					&rbd_dev->header.obj_order,
					&rbd_dev->header.image_size);
}

4875 4876 4877 4878 4879 4880 4881 4882 4883 4884
static int rbd_dev_v2_object_prefix(struct rbd_device *rbd_dev)
{
	void *reply_buf;
	int ret;
	void *p;

	reply_buf = kzalloc(RBD_OBJ_PREFIX_LEN_MAX, GFP_KERNEL);
	if (!reply_buf)
		return -ENOMEM;

4885 4886 4887
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_object_prefix",
				  NULL, 0, reply_buf, RBD_OBJ_PREFIX_LEN_MAX);
4888
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4889 4890 4891 4892 4893
	if (ret < 0)
		goto out;

	p = reply_buf;
	rbd_dev->header.object_prefix = ceph_extract_encoded_string(&p,
4894 4895
						p + ret, NULL, GFP_NOIO);
	ret = 0;
4896 4897 4898 4899 4900 4901 4902 4903 4904 4905 4906 4907 4908

	if (IS_ERR(rbd_dev->header.object_prefix)) {
		ret = PTR_ERR(rbd_dev->header.object_prefix);
		rbd_dev->header.object_prefix = NULL;
	} else {
		dout("  object_prefix = %s\n", rbd_dev->header.object_prefix);
	}
out:
	kfree(reply_buf);

	return ret;
}

4909 4910 4911 4912 4913 4914 4915
static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id,
		u64 *snap_features)
{
	__le64 snapid = cpu_to_le64(snap_id);
	struct {
		__le64 features;
		__le64 incompat;
4916
	} __attribute__ ((packed)) features_buf = { 0 };
4917
	u64 unsup;
4918 4919
	int ret;

4920 4921 4922 4923
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_features",
				  &snapid, sizeof(snapid),
				  &features_buf, sizeof(features_buf));
4924
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4925 4926
	if (ret < 0)
		return ret;
4927 4928
	if (ret < sizeof (features_buf))
		return -ERANGE;
A
Alex Elder 已提交
4929

4930 4931 4932 4933
	unsup = le64_to_cpu(features_buf.incompat) & ~RBD_FEATURES_SUPPORTED;
	if (unsup) {
		rbd_warn(rbd_dev, "image uses unsupported features: 0x%llx",
			 unsup);
A
Alex Elder 已提交
4934
		return -ENXIO;
4935
	}
A
Alex Elder 已提交
4936

4937 4938 4939
	*snap_features = le64_to_cpu(features_buf.features);

	dout("  snap_id 0x%016llx features = 0x%016llx incompat = 0x%016llx\n",
4940 4941 4942
		(unsigned long long)snap_id,
		(unsigned long long)*snap_features,
		(unsigned long long)le64_to_cpu(features_buf.incompat));
4943 4944 4945 4946 4947 4948 4949 4950 4951 4952

	return 0;
}

static int rbd_dev_v2_features(struct rbd_device *rbd_dev)
{
	return _rbd_dev_v2_snap_features(rbd_dev, CEPH_NOSNAP,
						&rbd_dev->header.features);
}

4953 4954 4955 4956 4957 4958 4959 4960
static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev)
{
	struct rbd_spec *parent_spec;
	size_t size;
	void *reply_buf = NULL;
	__le64 snapid;
	void *p;
	void *end;
A
Alex Elder 已提交
4961
	u64 pool_id;
4962
	char *image_id;
4963
	u64 snap_id;
4964 4965 4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976 4977 4978 4979 4980
	u64 overlap;
	int ret;

	parent_spec = rbd_spec_alloc();
	if (!parent_spec)
		return -ENOMEM;

	size = sizeof (__le64) +				/* pool_id */
		sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX +	/* image_id */
		sizeof (__le64) +				/* snap_id */
		sizeof (__le64);				/* overlap */
	reply_buf = kmalloc(size, GFP_KERNEL);
	if (!reply_buf) {
		ret = -ENOMEM;
		goto out_err;
	}

4981
	snapid = cpu_to_le64(rbd_dev->spec->snap_id);
4982 4983 4984
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_parent",
				  &snapid, sizeof(snapid), reply_buf, size);
4985
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
4986 4987 4988 4989
	if (ret < 0)
		goto out_err;

	p = reply_buf;
4990 4991
	end = reply_buf + ret;
	ret = -ERANGE;
A
Alex Elder 已提交
4992
	ceph_decode_64_safe(&p, end, pool_id, out_err);
4993 4994 4995 4996 4997 4998 4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 5009
	if (pool_id == CEPH_NOPOOL) {
		/*
		 * Either the parent never existed, or we have
		 * record of it but the image got flattened so it no
		 * longer has a parent.  When the parent of a
		 * layered image disappears we immediately set the
		 * overlap to 0.  The effect of this is that all new
		 * requests will be treated as if the image had no
		 * parent.
		 */
		if (rbd_dev->parent_overlap) {
			rbd_dev->parent_overlap = 0;
			rbd_dev_parent_put(rbd_dev);
			pr_info("%s: clone image has been flattened\n",
				rbd_dev->disk->disk_name);
		}

5010
		goto out;	/* No parent?  No problem. */
5011
	}
5012

5013 5014 5015
	/* The ceph file layout needs to fit pool id in 32 bits */

	ret = -EIO;
A
Alex Elder 已提交
5016
	if (pool_id > (u64)U32_MAX) {
5017
		rbd_warn(NULL, "parent pool id too large (%llu > %u)",
A
Alex Elder 已提交
5018
			(unsigned long long)pool_id, U32_MAX);
5019
		goto out_err;
A
Alex Elder 已提交
5020
	}
5021

A
Alex Elder 已提交
5022
	image_id = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
5023 5024 5025 5026
	if (IS_ERR(image_id)) {
		ret = PTR_ERR(image_id);
		goto out_err;
	}
5027
	ceph_decode_64_safe(&p, end, snap_id, out_err);
5028 5029
	ceph_decode_64_safe(&p, end, overlap, out_err);

5030 5031 5032 5033 5034 5035 5036 5037 5038
	/*
	 * The parent won't change (except when the clone is
	 * flattened, already handled that).  So we only need to
	 * record the parent spec we have not already done so.
	 */
	if (!rbd_dev->parent_spec) {
		parent_spec->pool_id = pool_id;
		parent_spec->image_id = image_id;
		parent_spec->snap_id = snap_id;
A
Alex Elder 已提交
5039 5040
		rbd_dev->parent_spec = parent_spec;
		parent_spec = NULL;	/* rbd_dev now owns this */
5041 5042
	} else {
		kfree(image_id);
5043 5044 5045
	}

	/*
5046 5047
	 * We always update the parent overlap.  If it's zero we issue
	 * a warning, as we will proceed as if there was no parent.
5048 5049 5050
	 */
	if (!overlap) {
		if (parent_spec) {
5051 5052 5053 5054
			/* refresh, careful to warn just once */
			if (rbd_dev->parent_overlap)
				rbd_warn(rbd_dev,
				    "clone now standalone (overlap became 0)");
5055
		} else {
5056 5057
			/* initial probe */
			rbd_warn(rbd_dev, "clone is standalone (overlap 0)");
5058
		}
A
Alex Elder 已提交
5059
	}
5060 5061
	rbd_dev->parent_overlap = overlap;

5062 5063 5064 5065 5066 5067 5068 5069 5070
out:
	ret = 0;
out_err:
	kfree(reply_buf);
	rbd_spec_put(parent_spec);

	return ret;
}

5071 5072 5073 5074 5075 5076 5077 5078 5079 5080 5081 5082 5083
static int rbd_dev_v2_striping_info(struct rbd_device *rbd_dev)
{
	struct {
		__le64 stripe_unit;
		__le64 stripe_count;
	} __attribute__ ((packed)) striping_info_buf = { 0 };
	size_t size = sizeof (striping_info_buf);
	void *p;
	u64 obj_size;
	u64 stripe_unit;
	u64 stripe_count;
	int ret;

5084 5085 5086
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				&rbd_dev->header_oloc, "get_stripe_unit_count",
				NULL, 0, &striping_info_buf, size);
5087 5088 5089 5090 5091 5092 5093 5094 5095 5096 5097 5098 5099
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
	if (ret < 0)
		return ret;
	if (ret < size)
		return -ERANGE;

	/*
	 * We don't actually support the "fancy striping" feature
	 * (STRIPINGV2) yet, but if the striping sizes are the
	 * defaults the behavior is the same as before.  So find
	 * out, and only fail if the image has non-default values.
	 */
	ret = -EINVAL;
I
Ilya Dryomov 已提交
5100
	obj_size = rbd_obj_bytes(&rbd_dev->header);
5101 5102 5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114
	p = &striping_info_buf;
	stripe_unit = ceph_decode_64(&p);
	if (stripe_unit != obj_size) {
		rbd_warn(rbd_dev, "unsupported stripe unit "
				"(got %llu want %llu)",
				stripe_unit, obj_size);
		return -EINVAL;
	}
	stripe_count = ceph_decode_64(&p);
	if (stripe_count != 1) {
		rbd_warn(rbd_dev, "unsupported stripe count "
				"(got %llu want 1)", stripe_count);
		return -EINVAL;
	}
5115 5116
	rbd_dev->header.stripe_unit = stripe_unit;
	rbd_dev->header.stripe_count = stripe_count;
5117 5118 5119 5120

	return 0;
}

5121 5122 5123 5124 5125 5126 5127 5128 5129 5130 5131 5132 5133 5134 5135 5136 5137 5138
static int rbd_dev_v2_data_pool(struct rbd_device *rbd_dev)
{
	__le64 data_pool_id;
	int ret;

	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_data_pool",
				  NULL, 0, &data_pool_id, sizeof(data_pool_id));
	if (ret < 0)
		return ret;
	if (ret < sizeof(data_pool_id))
		return -EBADMSG;

	rbd_dev->header.data_pool_id = le64_to_cpu(data_pool_id);
	WARN_ON(rbd_dev->header.data_pool_id == CEPH_NOPOOL);
	return 0;
}

5139 5140
static char *rbd_dev_image_name(struct rbd_device *rbd_dev)
{
5141
	CEPH_DEFINE_OID_ONSTACK(oid);
5142 5143 5144 5145 5146 5147 5148 5149 5150 5151 5152 5153
	size_t image_id_size;
	char *image_id;
	void *p;
	void *end;
	size_t size;
	void *reply_buf = NULL;
	size_t len = 0;
	char *image_name = NULL;
	int ret;

	rbd_assert(!rbd_dev->spec->image_name);

A
Alex Elder 已提交
5154 5155
	len = strlen(rbd_dev->spec->image_id);
	image_id_size = sizeof (__le32) + len;
5156 5157 5158 5159 5160
	image_id = kmalloc(image_id_size, GFP_KERNEL);
	if (!image_id)
		return NULL;

	p = image_id;
5161
	end = image_id + image_id_size;
5162
	ceph_encode_string(&p, end, rbd_dev->spec->image_id, (u32)len);
5163 5164 5165 5166 5167 5168

	size = sizeof (__le32) + RBD_IMAGE_NAME_LEN_MAX;
	reply_buf = kmalloc(size, GFP_KERNEL);
	if (!reply_buf)
		goto out;

5169 5170 5171 5172
	ceph_oid_printf(&oid, "%s", RBD_DIRECTORY);
	ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc,
				  "dir_get_name", image_id, image_id_size,
				  reply_buf, size);
5173 5174 5175
	if (ret < 0)
		goto out;
	p = reply_buf;
5176 5177
	end = reply_buf + ret;

5178 5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189
	image_name = ceph_extract_encoded_string(&p, end, &len, GFP_KERNEL);
	if (IS_ERR(image_name))
		image_name = NULL;
	else
		dout("%s: name is %s len is %zd\n", __func__, image_name, len);
out:
	kfree(reply_buf);
	kfree(image_id);

	return image_name;
}

5190 5191 5192 5193 5194 5195 5196 5197 5198 5199 5200 5201 5202 5203 5204 5205 5206 5207 5208 5209 5210 5211 5212 5213 5214 5215 5216 5217 5218 5219
static u64 rbd_v1_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
{
	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
	const char *snap_name;
	u32 which = 0;

	/* Skip over names until we find the one we are looking for */

	snap_name = rbd_dev->header.snap_names;
	while (which < snapc->num_snaps) {
		if (!strcmp(name, snap_name))
			return snapc->snaps[which];
		snap_name += strlen(snap_name) + 1;
		which++;
	}
	return CEPH_NOSNAP;
}

static u64 rbd_v2_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
{
	struct ceph_snap_context *snapc = rbd_dev->header.snapc;
	u32 which;
	bool found = false;
	u64 snap_id;

	for (which = 0; !found && which < snapc->num_snaps; which++) {
		const char *snap_name;

		snap_id = snapc->snaps[which];
		snap_name = rbd_dev_v2_snap_name(rbd_dev, snap_id);
5220 5221 5222 5223 5224 5225 5226
		if (IS_ERR(snap_name)) {
			/* ignore no-longer existing snapshots */
			if (PTR_ERR(snap_name) == -ENOENT)
				continue;
			else
				break;
		}
5227 5228 5229 5230 5231 5232 5233 5234 5235 5236 5237 5238 5239 5240 5241 5242 5243 5244
		found = !strcmp(name, snap_name);
		kfree(snap_name);
	}
	return found ? snap_id : CEPH_NOSNAP;
}

/*
 * Assumes name is never RBD_SNAP_HEAD_NAME; returns CEPH_NOSNAP if
 * no snapshot by that name is found, or if an error occurs.
 */
static u64 rbd_snap_id_by_name(struct rbd_device *rbd_dev, const char *name)
{
	if (rbd_dev->image_format == 1)
		return rbd_v1_snap_id_by_name(rbd_dev, name);

	return rbd_v2_snap_id_by_name(rbd_dev, name);
}

5245
/*
5246 5247 5248 5249 5250 5251 5252 5253 5254 5255 5256 5257 5258 5259 5260 5261 5262 5263 5264 5265 5266 5267 5268 5269 5270 5271 5272
 * An image being mapped will have everything but the snap id.
 */
static int rbd_spec_fill_snap_id(struct rbd_device *rbd_dev)
{
	struct rbd_spec *spec = rbd_dev->spec;

	rbd_assert(spec->pool_id != CEPH_NOPOOL && spec->pool_name);
	rbd_assert(spec->image_id && spec->image_name);
	rbd_assert(spec->snap_name);

	if (strcmp(spec->snap_name, RBD_SNAP_HEAD_NAME)) {
		u64 snap_id;

		snap_id = rbd_snap_id_by_name(rbd_dev, spec->snap_name);
		if (snap_id == CEPH_NOSNAP)
			return -ENOENT;

		spec->snap_id = snap_id;
	} else {
		spec->snap_id = CEPH_NOSNAP;
	}

	return 0;
}

/*
 * A parent image will have all ids but none of the names.
5273
 *
5274 5275
 * All names in an rbd spec are dynamically allocated.  It's OK if we
 * can't figure out the name for an image id.
5276
 */
5277
static int rbd_spec_fill_names(struct rbd_device *rbd_dev)
5278
{
5279 5280 5281 5282 5283
	struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc;
	struct rbd_spec *spec = rbd_dev->spec;
	const char *pool_name;
	const char *image_name;
	const char *snap_name;
5284 5285
	int ret;

5286 5287 5288
	rbd_assert(spec->pool_id != CEPH_NOPOOL);
	rbd_assert(spec->image_id);
	rbd_assert(spec->snap_id != CEPH_NOSNAP);
5289

5290
	/* Get the pool name; we have to make our own copy of this */
5291

5292 5293 5294
	pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, spec->pool_id);
	if (!pool_name) {
		rbd_warn(rbd_dev, "no pool with id %llu", spec->pool_id);
5295 5296
		return -EIO;
	}
5297 5298
	pool_name = kstrdup(pool_name, GFP_KERNEL);
	if (!pool_name)
5299 5300 5301 5302
		return -ENOMEM;

	/* Fetch the image name; tolerate failure here */

5303 5304
	image_name = rbd_dev_image_name(rbd_dev);
	if (!image_name)
A
Alex Elder 已提交
5305
		rbd_warn(rbd_dev, "unable to get image name");
5306

5307
	/* Fetch the snapshot name */
5308

5309
	snap_name = rbd_snap_name(rbd_dev, spec->snap_id);
5310 5311
	if (IS_ERR(snap_name)) {
		ret = PTR_ERR(snap_name);
5312
		goto out_err;
5313 5314 5315 5316 5317
	}

	spec->pool_name = pool_name;
	spec->image_name = image_name;
	spec->snap_name = snap_name;
5318 5319

	return 0;
5320

5321
out_err:
5322 5323
	kfree(image_name);
	kfree(pool_name);
5324 5325 5326
	return ret;
}

A
Alex Elder 已提交
5327
static int rbd_dev_v2_snap_context(struct rbd_device *rbd_dev)
5328 5329 5330 5331 5332 5333 5334 5335 5336 5337 5338 5339 5340 5341 5342 5343 5344 5345 5346 5347 5348 5349 5350
{
	size_t size;
	int ret;
	void *reply_buf;
	void *p;
	void *end;
	u64 seq;
	u32 snap_count;
	struct ceph_snap_context *snapc;
	u32 i;

	/*
	 * We'll need room for the seq value (maximum snapshot id),
	 * snapshot count, and array of that many snapshot ids.
	 * For now we have a fixed upper limit on the number we're
	 * prepared to receive.
	 */
	size = sizeof (__le64) + sizeof (__le32) +
			RBD_MAX_SNAP_COUNT * sizeof (__le64);
	reply_buf = kzalloc(size, GFP_KERNEL);
	if (!reply_buf)
		return -ENOMEM;

5351 5352 5353
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_snapcontext",
				  NULL, 0, reply_buf, size);
5354
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5355 5356 5357 5358
	if (ret < 0)
		goto out;

	p = reply_buf;
5359 5360
	end = reply_buf + ret;
	ret = -ERANGE;
5361 5362 5363 5364 5365 5366 5367 5368 5369 5370 5371 5372 5373 5374 5375 5376
	ceph_decode_64_safe(&p, end, seq, out);
	ceph_decode_32_safe(&p, end, snap_count, out);

	/*
	 * Make sure the reported number of snapshot ids wouldn't go
	 * beyond the end of our buffer.  But before checking that,
	 * make sure the computed size of the snapshot context we
	 * allocate is representable in a size_t.
	 */
	if (snap_count > (SIZE_MAX - sizeof (struct ceph_snap_context))
				 / sizeof (u64)) {
		ret = -EINVAL;
		goto out;
	}
	if (!ceph_has_room(&p, end, snap_count * sizeof (__le64)))
		goto out;
5377
	ret = 0;
5378

5379
	snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
5380 5381 5382 5383 5384 5385 5386 5387
	if (!snapc) {
		ret = -ENOMEM;
		goto out;
	}
	snapc->seq = seq;
	for (i = 0; i < snap_count; i++)
		snapc->snaps[i] = ceph_decode_64(&p);

5388
	ceph_put_snap_context(rbd_dev->header.snapc);
5389 5390 5391
	rbd_dev->header.snapc = snapc;

	dout("  snap context seq = %llu, snap_count = %u\n",
5392
		(unsigned long long)seq, (unsigned int)snap_count);
5393 5394 5395
out:
	kfree(reply_buf);

5396
	return ret;
5397 5398
}

5399 5400
static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev,
					u64 snap_id)
A
Alex Elder 已提交
5401 5402 5403
{
	size_t size;
	void *reply_buf;
5404
	__le64 snapid;
A
Alex Elder 已提交
5405 5406 5407 5408 5409 5410 5411 5412 5413 5414
	int ret;
	void *p;
	void *end;
	char *snap_name;

	size = sizeof (__le32) + RBD_MAX_SNAP_NAME_LEN;
	reply_buf = kmalloc(size, GFP_KERNEL);
	if (!reply_buf)
		return ERR_PTR(-ENOMEM);

5415
	snapid = cpu_to_le64(snap_id);
5416 5417 5418
	ret = rbd_obj_method_sync(rbd_dev, &rbd_dev->header_oid,
				  &rbd_dev->header_oloc, "get_snapshot_name",
				  &snapid, sizeof(snapid), reply_buf, size);
5419
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5420 5421
	if (ret < 0) {
		snap_name = ERR_PTR(ret);
A
Alex Elder 已提交
5422
		goto out;
5423
	}
A
Alex Elder 已提交
5424 5425

	p = reply_buf;
5426
	end = reply_buf + ret;
A
Alex Elder 已提交
5427
	snap_name = ceph_extract_encoded_string(&p, end, NULL, GFP_KERNEL);
5428
	if (IS_ERR(snap_name))
A
Alex Elder 已提交
5429 5430
		goto out;

5431
	dout("  snap_id 0x%016llx snap_name = %s\n",
5432
		(unsigned long long)snap_id, snap_name);
A
Alex Elder 已提交
5433 5434 5435
out:
	kfree(reply_buf);

5436
	return snap_name;
A
Alex Elder 已提交
5437 5438
}

5439
static int rbd_dev_v2_header_info(struct rbd_device *rbd_dev)
A
Alex Elder 已提交
5440
{
5441
	bool first_time = rbd_dev->header.object_prefix == NULL;
A
Alex Elder 已提交
5442 5443
	int ret;

5444 5445
	ret = rbd_dev_v2_image_size(rbd_dev);
	if (ret)
5446
		return ret;
5447

5448 5449 5450
	if (first_time) {
		ret = rbd_dev_v2_header_onetime(rbd_dev);
		if (ret)
5451
			return ret;
5452 5453
	}

A
Alex Elder 已提交
5454
	ret = rbd_dev_v2_snap_context(rbd_dev);
5455 5456 5457 5458
	if (ret && first_time) {
		kfree(rbd_dev->header.object_prefix);
		rbd_dev->header.object_prefix = NULL;
	}
A
Alex Elder 已提交
5459 5460 5461 5462

	return ret;
}

5463 5464 5465 5466 5467 5468 5469 5470 5471 5472
static int rbd_dev_header_info(struct rbd_device *rbd_dev)
{
	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));

	if (rbd_dev->image_format == 1)
		return rbd_dev_v1_header_info(rbd_dev);

	return rbd_dev_v2_header_info(rbd_dev);
}

5473 5474 5475
/*
 * Skips over white space at *buf, and updates *buf to point to the
 * first found non-space character (if any). Returns the length of
A
Alex Elder 已提交
5476 5477
 * the token (string of non-white space characters) found.  Note
 * that *buf must be terminated with '\0'.
5478 5479 5480 5481 5482 5483 5484 5485 5486 5487 5488 5489 5490 5491
 */
static inline size_t next_token(const char **buf)
{
        /*
        * These are the characters that produce nonzero for
        * isspace() in the "C" and "POSIX" locales.
        */
        const char *spaces = " \f\n\r\t\v";

        *buf += strspn(*buf, spaces);	/* Find start of token */

	return strcspn(*buf, spaces);   /* Return token length */
}

A
Alex Elder 已提交
5492 5493 5494 5495 5496 5497 5498 5499 5500 5501 5502 5503 5504 5505 5506 5507 5508 5509 5510 5511 5512 5513
/*
 * Finds the next token in *buf, dynamically allocates a buffer big
 * enough to hold a copy of it, and copies the token into the new
 * buffer.  The copy is guaranteed to be terminated with '\0'.  Note
 * that a duplicate buffer is created even for a zero-length token.
 *
 * Returns a pointer to the newly-allocated duplicate, or a null
 * pointer if memory for the duplicate was not available.  If
 * the lenp argument is a non-null pointer, the length of the token
 * (not including the '\0') is returned in *lenp.
 *
 * If successful, the *buf pointer will be updated to point beyond
 * the end of the found token.
 *
 * Note: uses GFP_KERNEL for allocation.
 */
static inline char *dup_token(const char **buf, size_t *lenp)
{
	char *dup;
	size_t len;

	len = next_token(buf);
A
Alex Elder 已提交
5514
	dup = kmemdup(*buf, len + 1, GFP_KERNEL);
A
Alex Elder 已提交
5515 5516 5517 5518 5519 5520 5521 5522 5523 5524 5525
	if (!dup)
		return NULL;
	*(dup + len) = '\0';
	*buf += len;

	if (lenp)
		*lenp = len;

	return dup;
}

5526
/*
5527 5528 5529 5530
 * Parse the options provided for an "rbd add" (i.e., rbd image
 * mapping) request.  These arrive via a write to /sys/bus/rbd/add,
 * and the data written is passed here via a NUL-terminated buffer.
 * Returns 0 if successful or an error code otherwise.
A
Alex Elder 已提交
5531
 *
5532 5533 5534 5535 5536 5537 5538 5539 5540 5541 5542 5543 5544 5545 5546 5547 5548 5549 5550 5551 5552 5553 5554 5555 5556 5557 5558 5559 5560 5561 5562 5563 5564 5565
 * The information extracted from these options is recorded in
 * the other parameters which return dynamically-allocated
 * structures:
 *  ceph_opts
 *      The address of a pointer that will refer to a ceph options
 *      structure.  Caller must release the returned pointer using
 *      ceph_destroy_options() when it is no longer needed.
 *  rbd_opts
 *	Address of an rbd options pointer.  Fully initialized by
 *	this function; caller must release with kfree().
 *  spec
 *	Address of an rbd image specification pointer.  Fully
 *	initialized by this function based on parsed options.
 *	Caller must release with rbd_spec_put().
 *
 * The options passed take this form:
 *  <mon_addrs> <options> <pool_name> <image_name> [<snap_id>]
 * where:
 *  <mon_addrs>
 *      A comma-separated list of one or more monitor addresses.
 *      A monitor address is an ip address, optionally followed
 *      by a port number (separated by a colon).
 *        I.e.:  ip1[:port1][,ip2[:port2]...]
 *  <options>
 *      A comma-separated list of ceph and/or rbd options.
 *  <pool_name>
 *      The name of the rados pool containing the rbd image.
 *  <image_name>
 *      The name of the image in that pool to map.
 *  <snap_id>
 *      An optional snapshot id.  If provided, the mapping will
 *      present data from the image at the time that snapshot was
 *      created.  The image head is used if no snapshot id is
 *      provided.  Snapshot mappings are always read-only.
5566
 */
5567
static int rbd_add_parse_args(const char *buf,
5568
				struct ceph_options **ceph_opts,
5569 5570
				struct rbd_options **opts,
				struct rbd_spec **rbd_spec)
5571
{
A
Alex Elder 已提交
5572
	size_t len;
5573
	char *options;
5574
	const char *mon_addrs;
5575
	char *snap_name;
5576
	size_t mon_addrs_size;
5577
	struct rbd_spec *spec = NULL;
5578
	struct rbd_options *rbd_opts = NULL;
5579
	struct ceph_options *copts;
5580
	int ret;
5581 5582 5583

	/* The first four tokens are required */

5584
	len = next_token(&buf);
5585 5586 5587 5588
	if (!len) {
		rbd_warn(NULL, "no monitor address(es) provided");
		return -EINVAL;
	}
5589
	mon_addrs = buf;
5590
	mon_addrs_size = len + 1;
5591
	buf += len;
5592

5593
	ret = -EINVAL;
5594 5595
	options = dup_token(&buf, NULL);
	if (!options)
5596
		return -ENOMEM;
5597 5598 5599 5600
	if (!*options) {
		rbd_warn(NULL, "no options provided");
		goto out_err;
	}
5601

5602 5603
	spec = rbd_spec_alloc();
	if (!spec)
5604
		goto out_mem;
5605 5606 5607 5608

	spec->pool_name = dup_token(&buf, NULL);
	if (!spec->pool_name)
		goto out_mem;
5609 5610 5611 5612
	if (!*spec->pool_name) {
		rbd_warn(NULL, "no pool name provided");
		goto out_err;
	}
5613

A
Alex Elder 已提交
5614
	spec->image_name = dup_token(&buf, NULL);
5615
	if (!spec->image_name)
5616
		goto out_mem;
5617 5618 5619 5620
	if (!*spec->image_name) {
		rbd_warn(NULL, "no image name provided");
		goto out_err;
	}
5621

5622 5623 5624 5625
	/*
	 * Snapshot name is optional; default is to use "-"
	 * (indicating the head/no snapshot).
	 */
5626
	len = next_token(&buf);
5627
	if (!len) {
5628 5629
		buf = RBD_SNAP_HEAD_NAME; /* No snapshot supplied */
		len = sizeof (RBD_SNAP_HEAD_NAME) - 1;
5630
	} else if (len > RBD_MAX_SNAP_NAME_LEN) {
5631
		ret = -ENAMETOOLONG;
5632
		goto out_err;
5633
	}
5634 5635
	snap_name = kmemdup(buf, len + 1, GFP_KERNEL);
	if (!snap_name)
5636
		goto out_mem;
5637 5638
	*(snap_name + len) = '\0';
	spec->snap_name = snap_name;
A
Alex Elder 已提交
5639

5640
	/* Initialize all rbd options to the defaults */
5641

5642 5643 5644 5645 5646
	rbd_opts = kzalloc(sizeof (*rbd_opts), GFP_KERNEL);
	if (!rbd_opts)
		goto out_mem;

	rbd_opts->read_only = RBD_READ_ONLY_DEFAULT;
I
Ilya Dryomov 已提交
5647
	rbd_opts->queue_depth = RBD_QUEUE_DEPTH_DEFAULT;
I
Ilya Dryomov 已提交
5648
	rbd_opts->lock_on_read = RBD_LOCK_ON_READ_DEFAULT;
I
Ilya Dryomov 已提交
5649
	rbd_opts->exclusive = RBD_EXCLUSIVE_DEFAULT;
A
Alex Elder 已提交
5650

5651
	copts = ceph_parse_options(options, mon_addrs,
5652
					mon_addrs + mon_addrs_size - 1,
5653
					parse_rbd_opts_token, rbd_opts);
5654 5655
	if (IS_ERR(copts)) {
		ret = PTR_ERR(copts);
5656 5657
		goto out_err;
	}
5658 5659 5660
	kfree(options);

	*ceph_opts = copts;
5661
	*opts = rbd_opts;
5662
	*rbd_spec = spec;
5663

5664
	return 0;
5665
out_mem:
5666
	ret = -ENOMEM;
A
Alex Elder 已提交
5667
out_err:
5668 5669
	kfree(rbd_opts);
	rbd_spec_put(spec);
5670
	kfree(options);
A
Alex Elder 已提交
5671

5672
	return ret;
5673 5674
}

5675 5676 5677 5678 5679
/*
 * Return pool id (>= 0) or a negative error code.
 */
static int rbd_add_get_pool_id(struct rbd_client *rbdc, const char *pool_name)
{
5680
	struct ceph_options *opts = rbdc->client->options;
5681 5682 5683 5684 5685 5686 5687
	u64 newest_epoch;
	int tries = 0;
	int ret;

again:
	ret = ceph_pg_poolid_by_name(rbdc->client->osdc.osdmap, pool_name);
	if (ret == -ENOENT && tries++ < 1) {
5688 5689
		ret = ceph_monc_get_version(&rbdc->client->monc, "osdmap",
					    &newest_epoch);
5690 5691 5692 5693
		if (ret < 0)
			return ret;

		if (rbdc->client->osdc.osdmap->epoch < newest_epoch) {
5694
			ceph_osdc_maybe_request_map(&rbdc->client->osdc);
5695
			(void) ceph_monc_wait_osdmap(&rbdc->client->monc,
5696 5697
						     newest_epoch,
						     opts->mount_timeout);
5698 5699 5700 5701 5702 5703 5704 5705 5706 5707
			goto again;
		} else {
			/* the osdmap we have is new enough */
			return -ENOENT;
		}
	}

	return ret;
}

I
Ilya Dryomov 已提交
5708 5709 5710 5711 5712 5713 5714 5715 5716 5717 5718 5719 5720 5721 5722 5723 5724 5725 5726 5727 5728 5729 5730 5731 5732 5733 5734
static void rbd_dev_image_unlock(struct rbd_device *rbd_dev)
{
	down_write(&rbd_dev->lock_rwsem);
	if (__rbd_is_lock_owner(rbd_dev))
		rbd_unlock(rbd_dev);
	up_write(&rbd_dev->lock_rwsem);
}

static int rbd_add_acquire_lock(struct rbd_device *rbd_dev)
{
	if (!(rbd_dev->header.features & RBD_FEATURE_EXCLUSIVE_LOCK)) {
		rbd_warn(rbd_dev, "exclusive-lock feature is not enabled");
		return -EINVAL;
	}

	/* FIXME: "rbd map --exclusive" should be in interruptible */
	down_read(&rbd_dev->lock_rwsem);
	rbd_wait_state_locked(rbd_dev);
	up_read(&rbd_dev->lock_rwsem);
	if (test_bit(RBD_DEV_FLAG_BLACKLISTED, &rbd_dev->flags)) {
		rbd_warn(rbd_dev, "failed to acquire exclusive lock");
		return -EROFS;
	}

	return 0;
}

A
Alex Elder 已提交
5735 5736 5737 5738 5739 5740 5741 5742 5743 5744 5745 5746 5747 5748 5749 5750 5751 5752
/*
 * An rbd format 2 image has a unique identifier, distinct from the
 * name given to it by the user.  Internally, that identifier is
 * what's used to specify the names of objects related to the image.
 *
 * A special "rbd id" object is used to map an rbd image name to its
 * id.  If that object doesn't exist, then there is no v2 rbd image
 * with the supplied name.
 *
 * This function will record the given rbd_dev's image_id field if
 * it can be determined, and in that case will return 0.  If any
 * errors occur a negative errno will be returned and the rbd_dev's
 * image_id field will be unchanged (and should be NULL).
 */
static int rbd_dev_image_id(struct rbd_device *rbd_dev)
{
	int ret;
	size_t size;
5753
	CEPH_DEFINE_OID_ONSTACK(oid);
A
Alex Elder 已提交
5754
	void *response;
5755
	char *image_id;
5756

A
Alex Elder 已提交
5757 5758 5759
	/*
	 * When probing a parent image, the image id is already
	 * known (and the image name likely is not).  There's no
5760 5761
	 * need to fetch the image id again in this case.  We
	 * do still need to set the image format though.
A
Alex Elder 已提交
5762
	 */
5763 5764 5765
	if (rbd_dev->spec->image_id) {
		rbd_dev->image_format = *rbd_dev->spec->image_id ? 2 : 1;

A
Alex Elder 已提交
5766
		return 0;
5767
	}
A
Alex Elder 已提交
5768

A
Alex Elder 已提交
5769 5770 5771 5772
	/*
	 * First, see if the format 2 image id file exists, and if
	 * so, get the image's persistent id from it.
	 */
5773 5774 5775 5776 5777 5778
	ret = ceph_oid_aprintf(&oid, GFP_KERNEL, "%s%s", RBD_ID_PREFIX,
			       rbd_dev->spec->image_name);
	if (ret)
		return ret;

	dout("rbd id object name is %s\n", oid.name);
A
Alex Elder 已提交
5779 5780 5781 5782 5783 5784 5785 5786 5787 5788

	/* Response will be an encoded string, which includes a length */

	size = sizeof (__le32) + RBD_IMAGE_ID_LEN_MAX;
	response = kzalloc(size, GFP_NOIO);
	if (!response) {
		ret = -ENOMEM;
		goto out;
	}

5789 5790
	/* If it doesn't exist we'll assume it's a format 1 image */

5791 5792 5793
	ret = rbd_obj_method_sync(rbd_dev, &oid, &rbd_dev->header_oloc,
				  "get_id", NULL, 0,
				  response, RBD_IMAGE_ID_LEN_MAX);
5794
	dout("%s: rbd_obj_method_sync returned %d\n", __func__, ret);
5795 5796 5797 5798 5799
	if (ret == -ENOENT) {
		image_id = kstrdup("", GFP_KERNEL);
		ret = image_id ? 0 : -ENOMEM;
		if (!ret)
			rbd_dev->image_format = 1;
5800
	} else if (ret >= 0) {
5801 5802 5803
		void *p = response;

		image_id = ceph_extract_encoded_string(&p, p + ret,
A
Alex Elder 已提交
5804
						NULL, GFP_NOIO);
5805
		ret = PTR_ERR_OR_ZERO(image_id);
5806 5807 5808 5809 5810 5811 5812
		if (!ret)
			rbd_dev->image_format = 2;
	}

	if (!ret) {
		rbd_dev->spec->image_id = image_id;
		dout("image_id is %s\n", image_id);
A
Alex Elder 已提交
5813 5814 5815
	}
out:
	kfree(response);
5816
	ceph_oid_destroy(&oid);
A
Alex Elder 已提交
5817 5818 5819
	return ret;
}

A
Alex Elder 已提交
5820 5821 5822 5823
/*
 * Undo whatever state changes are made by v1 or v2 header info
 * call.
 */
A
Alex Elder 已提交
5824 5825 5826 5827
static void rbd_dev_unprobe(struct rbd_device *rbd_dev)
{
	struct rbd_image_header	*header;

5828
	rbd_dev_parent_put(rbd_dev);
A
Alex Elder 已提交
5829 5830 5831 5832

	/* Free dynamic fields from the header, then zero it out */

	header = &rbd_dev->header;
5833
	ceph_put_snap_context(header->snapc);
A
Alex Elder 已提交
5834 5835 5836 5837 5838 5839
	kfree(header->snap_sizes);
	kfree(header->snap_names);
	kfree(header->object_prefix);
	memset(header, 0, sizeof (*header));
}

5840
static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev)
5841 5842 5843
{
	int ret;

5844
	ret = rbd_dev_v2_object_prefix(rbd_dev);
5845
	if (ret)
5846 5847
		goto out_err;

5848 5849 5850 5851
	/*
	 * Get the and check features for the image.  Currently the
	 * features are assumed to never change.
	 */
5852
	ret = rbd_dev_v2_features(rbd_dev);
5853
	if (ret)
5854
		goto out_err;
5855

5856 5857 5858 5859 5860 5861 5862
	/* If the image supports fancy striping, get its parameters */

	if (rbd_dev->header.features & RBD_FEATURE_STRIPINGV2) {
		ret = rbd_dev_v2_striping_info(rbd_dev);
		if (ret < 0)
			goto out_err;
	}
5863

5864 5865 5866 5867 5868 5869
	if (rbd_dev->header.features & RBD_FEATURE_DATA_POOL) {
		ret = rbd_dev_v2_data_pool(rbd_dev);
		if (ret)
			goto out_err;
	}

I
Ilya Dryomov 已提交
5870
	rbd_init_layout(rbd_dev);
A
Alex Elder 已提交
5871
	return 0;
I
Ilya Dryomov 已提交
5872

5873
out_err:
A
Alex Elder 已提交
5874
	rbd_dev->header.features = 0;
5875 5876
	kfree(rbd_dev->header.object_prefix);
	rbd_dev->header.object_prefix = NULL;
5877
	return ret;
5878 5879
}

5880 5881 5882 5883 5884 5885
/*
 * @depth is rbd_dev_image_probe() -> rbd_dev_probe_parent() ->
 * rbd_dev_image_probe() recursion depth, which means it's also the
 * length of the already discovered part of the parent chain.
 */
static int rbd_dev_probe_parent(struct rbd_device *rbd_dev, int depth)
A
Alex Elder 已提交
5886
{
5887
	struct rbd_device *parent = NULL;
5888 5889 5890 5891 5892
	int ret;

	if (!rbd_dev->parent_spec)
		return 0;

5893 5894 5895 5896 5897 5898
	if (++depth > RBD_MAX_PARENT_CHAIN_LEN) {
		pr_info("parent chain is too long (%d)\n", depth);
		ret = -EINVAL;
		goto out_err;
	}

5899
	parent = __rbd_dev_create(rbd_dev->rbd_client, rbd_dev->parent_spec);
5900 5901
	if (!parent) {
		ret = -ENOMEM;
5902
		goto out_err;
5903 5904 5905 5906 5907 5908 5909 5910
	}

	/*
	 * Images related by parent/child relationships always share
	 * rbd_client and spec/parent_spec, so bump their refcounts.
	 */
	__rbd_get_client(rbd_dev->rbd_client);
	rbd_spec_get(rbd_dev->parent_spec);
5911

5912
	ret = rbd_dev_image_probe(parent, depth);
5913 5914
	if (ret < 0)
		goto out_err;
5915

5916
	rbd_dev->parent = parent;
5917
	atomic_set(&rbd_dev->parent_ref, 1);
5918
	return 0;
5919

5920
out_err:
5921
	rbd_dev_unparent(rbd_dev);
5922
	rbd_dev_destroy(parent);
5923 5924 5925
	return ret;
}

5926 5927 5928 5929 5930 5931 5932 5933 5934
static void rbd_dev_device_release(struct rbd_device *rbd_dev)
{
	clear_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
	rbd_dev_mapping_clear(rbd_dev);
	rbd_free_disk(rbd_dev);
	if (!single_major)
		unregister_blkdev(rbd_dev->major, rbd_dev->name);
}

I
Ilya Dryomov 已提交
5935 5936 5937 5938
/*
 * rbd_dev->header_rwsem must be locked for write and will be unlocked
 * upon return.
 */
5939
static int rbd_dev_device_setup(struct rbd_device *rbd_dev)
5940
{
A
Alex Elder 已提交
5941
	int ret;
A
Alex Elder 已提交
5942

5943
	/* Record our major and minor device numbers. */
A
Alex Elder 已提交
5944

5945 5946 5947
	if (!single_major) {
		ret = register_blkdev(0, rbd_dev->name);
		if (ret < 0)
5948
			goto err_out_unlock;
5949 5950 5951 5952 5953 5954 5955

		rbd_dev->major = ret;
		rbd_dev->minor = 0;
	} else {
		rbd_dev->major = rbd_major;
		rbd_dev->minor = rbd_dev_id_to_minor(rbd_dev->dev_id);
	}
A
Alex Elder 已提交
5956 5957 5958 5959 5960 5961 5962

	/* Set up the blkdev mapping. */

	ret = rbd_init_disk(rbd_dev);
	if (ret)
		goto err_out_blkdev;

5963
	ret = rbd_dev_mapping_set(rbd_dev);
A
Alex Elder 已提交
5964 5965
	if (ret)
		goto err_out_disk;
I
Ilya Dryomov 已提交
5966

5967
	set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
5968
	set_disk_ro(rbd_dev->disk, rbd_dev->opts->read_only);
5969

5970
	ret = dev_set_name(&rbd_dev->dev, "%d", rbd_dev->dev_id);
5971
	if (ret)
5972
		goto err_out_mapping;
A
Alex Elder 已提交
5973

5974
	set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
I
Ilya Dryomov 已提交
5975
	up_write(&rbd_dev->header_rwsem);
5976
	return 0;
5977

5978 5979
err_out_mapping:
	rbd_dev_mapping_clear(rbd_dev);
A
Alex Elder 已提交
5980 5981 5982
err_out_disk:
	rbd_free_disk(rbd_dev);
err_out_blkdev:
5983 5984
	if (!single_major)
		unregister_blkdev(rbd_dev->major, rbd_dev->name);
I
Ilya Dryomov 已提交
5985 5986
err_out_unlock:
	up_write(&rbd_dev->header_rwsem);
A
Alex Elder 已提交
5987 5988 5989
	return ret;
}

A
Alex Elder 已提交
5990 5991 5992
static int rbd_dev_header_name(struct rbd_device *rbd_dev)
{
	struct rbd_spec *spec = rbd_dev->spec;
5993
	int ret;
A
Alex Elder 已提交
5994 5995 5996 5997 5998

	/* Record the header object name for this rbd image. */

	rbd_assert(rbd_image_format_valid(rbd_dev->image_format));
	if (rbd_dev->image_format == 1)
5999 6000
		ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s",
				       spec->image_name, RBD_SUFFIX);
A
Alex Elder 已提交
6001
	else
6002 6003
		ret = ceph_oid_aprintf(&rbd_dev->header_oid, GFP_KERNEL, "%s%s",
				       RBD_HEADER_PREFIX, spec->image_id);
A
Alex Elder 已提交
6004

6005
	return ret;
A
Alex Elder 已提交
6006 6007
}

6008 6009
static void rbd_dev_image_release(struct rbd_device *rbd_dev)
{
A
Alex Elder 已提交
6010
	rbd_dev_unprobe(rbd_dev);
6011 6012
	if (rbd_dev->opts)
		rbd_unregister_watch(rbd_dev);
A
Alex Elder 已提交
6013 6014 6015
	rbd_dev->image_format = 0;
	kfree(rbd_dev->spec->image_id);
	rbd_dev->spec->image_id = NULL;
6016 6017
}

6018 6019
/*
 * Probe for the existence of the header object for the given rbd
6020 6021 6022
 * device.  If this image is the one being mapped (i.e., not a
 * parent), initiate a watch on its header object before using that
 * object to get detailed information about the rbd image.
6023
 */
6024
static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth)
6025 6026 6027 6028
{
	int ret;

	/*
A
Alex Elder 已提交
6029 6030 6031 6032
	 * Get the id from the image id object.  Unless there's an
	 * error, rbd_dev->spec->image_id will be filled in with
	 * a dynamically-allocated string, and rbd_dev->image_format
	 * will be set to either 1 or 2.
6033 6034 6035
	 */
	ret = rbd_dev_image_id(rbd_dev);
	if (ret)
6036 6037
		return ret;

A
Alex Elder 已提交
6038 6039 6040 6041
	ret = rbd_dev_header_name(rbd_dev);
	if (ret)
		goto err_out_format;

6042
	if (!depth) {
6043
		ret = rbd_register_watch(rbd_dev);
6044 6045 6046 6047 6048
		if (ret) {
			if (ret == -ENOENT)
				pr_info("image %s/%s does not exist\n",
					rbd_dev->spec->pool_name,
					rbd_dev->spec->image_name);
6049
			goto err_out_format;
6050
		}
6051
	}
6052

6053
	ret = rbd_dev_header_info(rbd_dev);
6054
	if (ret)
6055
		goto err_out_watch;
A
Alex Elder 已提交
6056

6057 6058 6059 6060 6061 6062
	/*
	 * If this image is the one being mapped, we have pool name and
	 * id, image name and id, and snap name - need to fill snap id.
	 * Otherwise this is a parent image, identified by pool, image
	 * and snap ids - need to fill in names for those ids.
	 */
6063
	if (!depth)
6064 6065 6066
		ret = rbd_spec_fill_snap_id(rbd_dev);
	else
		ret = rbd_spec_fill_names(rbd_dev);
6067 6068 6069 6070 6071 6072
	if (ret) {
		if (ret == -ENOENT)
			pr_info("snap %s/%s@%s does not exist\n",
				rbd_dev->spec->pool_name,
				rbd_dev->spec->image_name,
				rbd_dev->spec->snap_name);
A
Alex Elder 已提交
6073
		goto err_out_probe;
6074
	}
6075

6076 6077 6078 6079 6080 6081 6082 6083 6084
	if (rbd_dev->header.features & RBD_FEATURE_LAYERING) {
		ret = rbd_dev_v2_parent_info(rbd_dev);
		if (ret)
			goto err_out_probe;

		/*
		 * Need to warn users if this image is the one being
		 * mapped and has a parent.
		 */
6085
		if (!depth && rbd_dev->parent_spec)
6086 6087 6088 6089
			rbd_warn(rbd_dev,
				 "WARNING: kernel layering is EXPERIMENTAL!");
	}

6090
	ret = rbd_dev_probe_parent(rbd_dev, depth);
A
Alex Elder 已提交
6091 6092 6093 6094
	if (ret)
		goto err_out_probe;

	dout("discovered format %u image, header name is %s\n",
6095
		rbd_dev->image_format, rbd_dev->header_oid.name);
A
Alex Elder 已提交
6096
	return 0;
6097

A
Alex Elder 已提交
6098 6099
err_out_probe:
	rbd_dev_unprobe(rbd_dev);
6100
err_out_watch:
6101
	if (!depth)
6102
		rbd_unregister_watch(rbd_dev);
A
Alex Elder 已提交
6103 6104
err_out_format:
	rbd_dev->image_format = 0;
6105 6106
	kfree(rbd_dev->spec->image_id);
	rbd_dev->spec->image_id = NULL;
6107 6108 6109
	return ret;
}

6110 6111 6112
static ssize_t do_rbd_add(struct bus_type *bus,
			  const char *buf,
			  size_t count)
6113
{
6114
	struct rbd_device *rbd_dev = NULL;
6115
	struct ceph_options *ceph_opts = NULL;
6116
	struct rbd_options *rbd_opts = NULL;
6117
	struct rbd_spec *spec = NULL;
6118
	struct rbd_client *rbdc;
6119
	int rc;
6120 6121 6122 6123 6124

	if (!try_module_get(THIS_MODULE))
		return -ENODEV;

	/* parse add command */
6125
	rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
6126
	if (rc < 0)
6127
		goto out;
6128

6129 6130 6131
	rbdc = rbd_get_client(ceph_opts);
	if (IS_ERR(rbdc)) {
		rc = PTR_ERR(rbdc);
6132
		goto err_out_args;
6133
	}
6134 6135

	/* pick the pool */
6136
	rc = rbd_add_get_pool_id(rbdc, spec->pool_name);
6137 6138 6139
	if (rc < 0) {
		if (rc == -ENOENT)
			pr_info("pool %s does not exist\n", spec->pool_name);
6140
		goto err_out_client;
6141
	}
A
Alex Elder 已提交
6142
	spec->pool_id = (u64)rc;
6143

6144
	rbd_dev = rbd_dev_create(rbdc, spec, rbd_opts);
6145 6146
	if (!rbd_dev) {
		rc = -ENOMEM;
6147
		goto err_out_client;
6148
	}
6149 6150
	rbdc = NULL;		/* rbd_dev now owns this */
	spec = NULL;		/* rbd_dev now owns this */
6151
	rbd_opts = NULL;	/* rbd_dev now owns this */
6152

6153 6154 6155 6156 6157 6158
	rbd_dev->config_info = kstrdup(buf, GFP_KERNEL);
	if (!rbd_dev->config_info) {
		rc = -ENOMEM;
		goto err_out_rbd_dev;
	}

I
Ilya Dryomov 已提交
6159
	down_write(&rbd_dev->header_rwsem);
6160
	rc = rbd_dev_image_probe(rbd_dev, 0);
6161 6162
	if (rc < 0) {
		up_write(&rbd_dev->header_rwsem);
6163
		goto err_out_rbd_dev;
6164
	}
6165

6166 6167
	/* If we are mapping a snapshot it must be marked read-only */
	if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
6168
		rbd_dev->opts->read_only = true;
6169

6170
	rc = rbd_dev_device_setup(rbd_dev);
6171
	if (rc)
6172
		goto err_out_image_probe;
A
Alex Elder 已提交
6173

I
Ilya Dryomov 已提交
6174 6175 6176 6177
	if (rbd_dev->opts->exclusive) {
		rc = rbd_add_acquire_lock(rbd_dev);
		if (rc)
			goto err_out_device_setup;
A
Alex Elder 已提交
6178 6179
	}

6180 6181 6182 6183
	/* Everything's ready.  Announce the disk to the world. */

	rc = device_add(&rbd_dev->dev);
	if (rc)
I
Ilya Dryomov 已提交
6184
		goto err_out_image_lock;
6185 6186 6187 6188 6189 6190 6191 6192 6193 6194 6195 6196

	add_disk(rbd_dev->disk);
	/* see rbd_init_disk() */
	blk_put_queue(rbd_dev->disk->queue);

	spin_lock(&rbd_dev_list_lock);
	list_add_tail(&rbd_dev->node, &rbd_dev_list);
	spin_unlock(&rbd_dev_list_lock);

	pr_info("%s: capacity %llu features 0x%llx\n", rbd_dev->disk->disk_name,
		(unsigned long long)get_capacity(rbd_dev->disk) << SECTOR_SHIFT,
		rbd_dev->header.features);
6197 6198 6199 6200
	rc = count;
out:
	module_put(THIS_MODULE);
	return rc;
6201

I
Ilya Dryomov 已提交
6202 6203
err_out_image_lock:
	rbd_dev_image_unlock(rbd_dev);
6204 6205
err_out_device_setup:
	rbd_dev_device_release(rbd_dev);
6206 6207
err_out_image_probe:
	rbd_dev_image_release(rbd_dev);
6208 6209
err_out_rbd_dev:
	rbd_dev_destroy(rbd_dev);
6210
err_out_client:
6211
	rbd_put_client(rbdc);
6212
err_out_args:
6213
	rbd_spec_put(spec);
6214
	kfree(rbd_opts);
6215
	goto out;
6216 6217
}

6218 6219 6220 6221 6222 6223 6224 6225 6226 6227 6228 6229 6230 6231 6232 6233 6234
static ssize_t rbd_add(struct bus_type *bus,
		       const char *buf,
		       size_t count)
{
	if (single_major)
		return -EINVAL;

	return do_rbd_add(bus, buf, count);
}

static ssize_t rbd_add_single_major(struct bus_type *bus,
				    const char *buf,
				    size_t count)
{
	return do_rbd_add(bus, buf, count);
}

6235 6236
static void rbd_dev_remove_parent(struct rbd_device *rbd_dev)
{
A
Alex Elder 已提交
6237
	while (rbd_dev->parent) {
6238 6239 6240 6241 6242 6243 6244 6245 6246 6247 6248 6249
		struct rbd_device *first = rbd_dev;
		struct rbd_device *second = first->parent;
		struct rbd_device *third;

		/*
		 * Follow to the parent with no grandparent and
		 * remove it.
		 */
		while (second && (third = second->parent)) {
			first = second;
			second = third;
		}
A
Alex Elder 已提交
6250
		rbd_assert(second);
6251
		rbd_dev_image_release(second);
6252
		rbd_dev_destroy(second);
A
Alex Elder 已提交
6253 6254 6255 6256
		first->parent = NULL;
		first->parent_overlap = 0;

		rbd_assert(first->parent_spec);
6257 6258 6259 6260 6261
		rbd_spec_put(first->parent_spec);
		first->parent_spec = NULL;
	}
}

6262 6263 6264
static ssize_t do_rbd_remove(struct bus_type *bus,
			     const char *buf,
			     size_t count)
6265 6266
{
	struct rbd_device *rbd_dev = NULL;
6267 6268
	struct list_head *tmp;
	int dev_id;
M
Mike Christie 已提交
6269
	char opt_buf[6];
6270
	bool already = false;
M
Mike Christie 已提交
6271
	bool force = false;
6272
	int ret;
6273

M
Mike Christie 已提交
6274 6275 6276 6277 6278
	dev_id = -1;
	opt_buf[0] = '\0';
	sscanf(buf, "%d %5s", &dev_id, opt_buf);
	if (dev_id < 0) {
		pr_err("dev_id out of range\n");
6279
		return -EINVAL;
M
Mike Christie 已提交
6280 6281 6282 6283 6284 6285 6286 6287 6288
	}
	if (opt_buf[0] != '\0') {
		if (!strcmp(opt_buf, "force")) {
			force = true;
		} else {
			pr_err("bad remove option at '%s'\n", opt_buf);
			return -EINVAL;
		}
	}
6289

6290 6291 6292 6293 6294 6295 6296 6297
	ret = -ENOENT;
	spin_lock(&rbd_dev_list_lock);
	list_for_each(tmp, &rbd_dev_list) {
		rbd_dev = list_entry(tmp, struct rbd_device, node);
		if (rbd_dev->dev_id == dev_id) {
			ret = 0;
			break;
		}
6298
	}
6299 6300
	if (!ret) {
		spin_lock_irq(&rbd_dev->lock);
M
Mike Christie 已提交
6301
		if (rbd_dev->open_count && !force)
6302 6303
			ret = -EBUSY;
		else
6304 6305
			already = test_and_set_bit(RBD_DEV_FLAG_REMOVING,
							&rbd_dev->flags);
6306 6307 6308
		spin_unlock_irq(&rbd_dev->lock);
	}
	spin_unlock(&rbd_dev_list_lock);
6309
	if (ret < 0 || already)
6310
		return ret;
6311

M
Mike Christie 已提交
6312 6313 6314 6315 6316 6317 6318 6319 6320
	if (force) {
		/*
		 * Prevent new IO from being queued and wait for existing
		 * IO to complete/fail.
		 */
		blk_mq_freeze_queue(rbd_dev->disk->queue);
		blk_set_queue_dying(rbd_dev->disk->queue);
	}

6321 6322 6323 6324 6325
	del_gendisk(rbd_dev->disk);
	spin_lock(&rbd_dev_list_lock);
	list_del_init(&rbd_dev->node);
	spin_unlock(&rbd_dev_list_lock);
	device_del(&rbd_dev->dev);
6326

I
Ilya Dryomov 已提交
6327
	rbd_dev_image_unlock(rbd_dev);
6328
	rbd_dev_device_release(rbd_dev);
6329
	rbd_dev_image_release(rbd_dev);
6330
	rbd_dev_destroy(rbd_dev);
6331
	return count;
6332 6333
}

6334 6335 6336 6337 6338 6339 6340 6341 6342 6343 6344 6345 6346 6347 6348 6349 6350
static ssize_t rbd_remove(struct bus_type *bus,
			  const char *buf,
			  size_t count)
{
	if (single_major)
		return -EINVAL;

	return do_rbd_remove(bus, buf, count);
}

static ssize_t rbd_remove_single_major(struct bus_type *bus,
				       const char *buf,
				       size_t count)
{
	return do_rbd_remove(bus, buf, count);
}

6351 6352
/*
 * create control files in sysfs
6353
 * /sys/bus/rbd/...
6354 6355 6356
 */
static int rbd_sysfs_init(void)
{
6357
	int ret;
6358

6359
	ret = device_register(&rbd_root_dev);
A
Alex Elder 已提交
6360
	if (ret < 0)
6361
		return ret;
6362

6363 6364 6365
	ret = bus_register(&rbd_bus_type);
	if (ret < 0)
		device_unregister(&rbd_root_dev);
6366 6367 6368 6369 6370 6371

	return ret;
}

static void rbd_sysfs_cleanup(void)
{
6372
	bus_unregister(&rbd_bus_type);
6373
	device_unregister(&rbd_root_dev);
6374 6375
}

6376 6377 6378
static int rbd_slab_init(void)
{
	rbd_assert(!rbd_img_request_cache);
G
Geliang Tang 已提交
6379
	rbd_img_request_cache = KMEM_CACHE(rbd_img_request, 0);
6380 6381 6382 6383
	if (!rbd_img_request_cache)
		return -ENOMEM;

	rbd_assert(!rbd_obj_request_cache);
G
Geliang Tang 已提交
6384
	rbd_obj_request_cache = KMEM_CACHE(rbd_obj_request, 0);
6385 6386 6387
	if (!rbd_obj_request_cache)
		goto out_err;

6388 6389 6390 6391 6392
	rbd_assert(!rbd_bio_clone);
	rbd_bio_clone = bioset_create(BIO_POOL_SIZE, 0, 0);
	if (!rbd_bio_clone)
		goto out_err_clone;

6393
	return 0;
6394

6395 6396 6397
out_err_clone:
	kmem_cache_destroy(rbd_obj_request_cache);
	rbd_obj_request_cache = NULL;
6398
out_err:
6399 6400
	kmem_cache_destroy(rbd_img_request_cache);
	rbd_img_request_cache = NULL;
6401 6402 6403 6404 6405
	return -ENOMEM;
}

static void rbd_slab_exit(void)
{
6406 6407 6408 6409
	rbd_assert(rbd_obj_request_cache);
	kmem_cache_destroy(rbd_obj_request_cache);
	rbd_obj_request_cache = NULL;

6410 6411 6412
	rbd_assert(rbd_img_request_cache);
	kmem_cache_destroy(rbd_img_request_cache);
	rbd_img_request_cache = NULL;
6413 6414 6415 6416

	rbd_assert(rbd_bio_clone);
	bioset_free(rbd_bio_clone);
	rbd_bio_clone = NULL;
6417 6418
}

A
Alex Elder 已提交
6419
static int __init rbd_init(void)
6420 6421 6422
{
	int rc;

6423 6424 6425 6426
	if (!libceph_compatible(NULL)) {
		rbd_warn(NULL, "libceph incompatibility (quitting)");
		return -EINVAL;
	}
I
Ilya Dryomov 已提交
6427

6428
	rc = rbd_slab_init();
6429 6430
	if (rc)
		return rc;
I
Ilya Dryomov 已提交
6431

6432 6433
	/*
	 * The number of active work items is limited by the number of
I
Ilya Dryomov 已提交
6434
	 * rbd devices * queue depth, so leave @max_active at default.
6435 6436 6437 6438 6439 6440 6441
	 */
	rbd_wq = alloc_workqueue(RBD_DRV_NAME, WQ_MEM_RECLAIM, 0);
	if (!rbd_wq) {
		rc = -ENOMEM;
		goto err_out_slab;
	}

6442 6443 6444 6445
	if (single_major) {
		rbd_major = register_blkdev(0, RBD_DRV_NAME);
		if (rbd_major < 0) {
			rc = rbd_major;
6446
			goto err_out_wq;
6447 6448 6449
		}
	}

6450 6451
	rc = rbd_sysfs_init();
	if (rc)
6452 6453 6454 6455 6456 6457
		goto err_out_blkdev;

	if (single_major)
		pr_info("loaded (major %d)\n", rbd_major);
	else
		pr_info("loaded\n");
6458

I
Ilya Dryomov 已提交
6459 6460
	return 0;

6461 6462 6463
err_out_blkdev:
	if (single_major)
		unregister_blkdev(rbd_major, RBD_DRV_NAME);
6464 6465
err_out_wq:
	destroy_workqueue(rbd_wq);
I
Ilya Dryomov 已提交
6466 6467
err_out_slab:
	rbd_slab_exit();
6468
	return rc;
6469 6470
}

A
Alex Elder 已提交
6471
static void __exit rbd_exit(void)
6472
{
I
Ilya Dryomov 已提交
6473
	ida_destroy(&rbd_dev_id_ida);
6474
	rbd_sysfs_cleanup();
6475 6476
	if (single_major)
		unregister_blkdev(rbd_major, RBD_DRV_NAME);
6477
	destroy_workqueue(rbd_wq);
6478
	rbd_slab_exit();
6479 6480 6481 6482 6483
}

module_init(rbd_init);
module_exit(rbd_exit);

A
Alex Elder 已提交
6484
MODULE_AUTHOR("Alex Elder <elder@inktank.com>");
6485 6486 6487 6488 6489
MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
/* following authorship retained from original osdblk.c */
MODULE_AUTHOR("Jeff Garzik <jeff@garzik.org>");

6490
MODULE_DESCRIPTION("RADOS Block Device (RBD) driver");
6491
MODULE_LICENSE("GPL");