blkdev.h 39.9 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3
#ifndef _LINUX_BLKDEV_H
#define _LINUX_BLKDEV_H

J
Jens Axboe 已提交
4 5
#ifdef CONFIG_BLOCK

6
#include <linux/sched.h>
L
Linus Torvalds 已提交
7 8 9 10 11 12 13 14 15 16 17 18
#include <linux/major.h>
#include <linux/genhd.h>
#include <linux/list.h>
#include <linux/timer.h>
#include <linux/workqueue.h>
#include <linux/pagemap.h>
#include <linux/backing-dev.h>
#include <linux/wait.h>
#include <linux/mempool.h>
#include <linux/bio.h>
#include <linux/module.h>
#include <linux/stringify.h>
19
#include <linux/gfp.h>
20
#include <linux/bsg.h>
21
#include <linux/smp.h>
L
Linus Torvalds 已提交
22 23 24

#include <asm/scatterlist.h>

25 26
struct scsi_ioctl_command;

L
Linus Torvalds 已提交
27 28 29
struct request_queue;
struct elevator_queue;
struct request_pm_state;
30
struct blk_trace;
31 32
struct request;
struct sg_io_hdr;
L
Linus Torvalds 已提交
33 34 35 36 37

#define BLKDEV_MIN_RQ	4
#define BLKDEV_MAX_RQ	128	/* Default maximum */

struct request;
38
typedef void (rq_end_io_fn)(struct request *, int);
L
Linus Torvalds 已提交
39 40

struct request_list {
41 42 43 44
	/*
	 * count[], starved[], and wait[] are indexed by
	 * BLK_RW_SYNC/BLK_RW_ASYNC
	 */
L
Linus Torvalds 已提交
45 46
	int count[2];
	int starved[2];
T
Tejun Heo 已提交
47
	int elvpriv;
L
Linus Torvalds 已提交
48 49 50 51
	mempool_t *rq_pool;
	wait_queue_head_t wait[2];
};

52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69
/*
 * request command types
 */
enum rq_cmd_type_bits {
	REQ_TYPE_FS		= 1,	/* fs request */
	REQ_TYPE_BLOCK_PC,		/* scsi command */
	REQ_TYPE_SENSE,			/* sense request */
	REQ_TYPE_PM_SUSPEND,		/* suspend request */
	REQ_TYPE_PM_RESUME,		/* resume request */
	REQ_TYPE_PM_SHUTDOWN,		/* shutdown request */
	REQ_TYPE_SPECIAL,		/* driver defined type */
	REQ_TYPE_LINUX_BLOCK,		/* generic block layer message */
	/*
	 * for ATA/ATAPI devices. this really doesn't belong here, ide should
	 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
	 * private REQ_LB opcodes to differentiate what type of request this is
	 */
	REQ_TYPE_ATA_TASKFILE,
70
	REQ_TYPE_ATA_PC,
71 72 73 74 75 76 77 78 79 80 81 82 83
};

/*
 * For request of type REQ_TYPE_LINUX_BLOCK, rq->cmd[0] is the opcode being
 * sent down (similar to how REQ_TYPE_BLOCK_PC means that ->cmd[] holds a
 * SCSI cdb.
 *
 * 0x00 -> 0x3f are driver private, to be used for whatever purpose they need,
 * typically to differentiate REQ_TYPE_SPECIAL requests.
 *
 */
enum {
	REQ_LB_OP_EJECT	= 0x40,		/* eject request */
D
David Woodhouse 已提交
84
	REQ_LB_OP_FLUSH = 0x41,		/* flush request */
85 86 87
};

/*
88
 * request type modified bits. first four bits match BIO_RW* bits, important
89 90 91
 */
enum rq_flag_bits {
	__REQ_RW,		/* not set, read. set, write */
92 93 94
	__REQ_FAILFAST_DEV,	/* no driver retries of device errors */
	__REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */
	__REQ_FAILFAST_DRIVER,	/* no driver retries of driver errors */
95
	/* above flags must match BIO_RW_* */
D
David Woodhouse 已提交
96
	__REQ_DISCARD,		/* request to discard sectors */
97 98 99 100 101 102 103 104 105 106 107 108 109
	__REQ_SORTED,		/* elevator knows about this request */
	__REQ_SOFTBARRIER,	/* may not be passed by ioscheduler */
	__REQ_HARDBARRIER,	/* may not be passed by drive either */
	__REQ_FUA,		/* forced unit access */
	__REQ_NOMERGE,		/* don't touch this for merging */
	__REQ_STARTED,		/* drive already may have started this one */
	__REQ_DONTPREP,		/* don't call prep for this one */
	__REQ_QUEUED,		/* uses queueing */
	__REQ_ELVPRIV,		/* elevator private data attached */
	__REQ_FAILED,		/* set if the request failed */
	__REQ_QUIET,		/* don't worry about errors */
	__REQ_PREEMPT,		/* set for "ide_preempt" requests */
	__REQ_ORDERED_COLOR,	/* is before or after barrier */
110
	__REQ_RW_SYNC,		/* request is sync (sync write or read) */
111
	__REQ_ALLOCED,		/* request came from our alloc pool */
112
	__REQ_RW_META,		/* metadata io request */
113
	__REQ_COPY_USER,	/* contains copies of user pages */
114
	__REQ_INTEGRITY,	/* integrity metadata has been remapped */
115
	__REQ_NOIDLE,		/* Don't anticipate more IO after this one */
116
	__REQ_IO_STAT,		/* account I/O stat */
117
	__REQ_MIXED_MERGE,	/* merge of different types, fail separately */
118 119 120 121
	__REQ_NR_BITS,		/* stops here */
};

#define REQ_RW		(1 << __REQ_RW)
122 123 124
#define REQ_FAILFAST_DEV	(1 << __REQ_FAILFAST_DEV)
#define REQ_FAILFAST_TRANSPORT	(1 << __REQ_FAILFAST_TRANSPORT)
#define REQ_FAILFAST_DRIVER	(1 << __REQ_FAILFAST_DRIVER)
D
David Woodhouse 已提交
125
#define REQ_DISCARD	(1 << __REQ_DISCARD)
126 127 128 129 130 131 132 133 134 135 136 137 138 139
#define REQ_SORTED	(1 << __REQ_SORTED)
#define REQ_SOFTBARRIER	(1 << __REQ_SOFTBARRIER)
#define REQ_HARDBARRIER	(1 << __REQ_HARDBARRIER)
#define REQ_FUA		(1 << __REQ_FUA)
#define REQ_NOMERGE	(1 << __REQ_NOMERGE)
#define REQ_STARTED	(1 << __REQ_STARTED)
#define REQ_DONTPREP	(1 << __REQ_DONTPREP)
#define REQ_QUEUED	(1 << __REQ_QUEUED)
#define REQ_ELVPRIV	(1 << __REQ_ELVPRIV)
#define REQ_FAILED	(1 << __REQ_FAILED)
#define REQ_QUIET	(1 << __REQ_QUIET)
#define REQ_PREEMPT	(1 << __REQ_PREEMPT)
#define REQ_ORDERED_COLOR	(1 << __REQ_ORDERED_COLOR)
#define REQ_RW_SYNC	(1 << __REQ_RW_SYNC)
140
#define REQ_ALLOCED	(1 << __REQ_ALLOCED)
141
#define REQ_RW_META	(1 << __REQ_RW_META)
142
#define REQ_COPY_USER	(1 << __REQ_COPY_USER)
143
#define REQ_INTEGRITY	(1 << __REQ_INTEGRITY)
144
#define REQ_NOIDLE	(1 << __REQ_NOIDLE)
145
#define REQ_IO_STAT	(1 << __REQ_IO_STAT)
146
#define REQ_MIXED_MERGE	(1 << __REQ_MIXED_MERGE)
147

148 149 150
#define REQ_FAILFAST_MASK	(REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | \
				 REQ_FAILFAST_DRIVER)

L
Linus Torvalds 已提交
151 152 153
#define BLK_MAX_CDB	16

/*
J
Jens Axboe 已提交
154 155 156
 * try to put the fields that are referenced together in the same cacheline.
 * if you modify this structure, be sure to check block/blk-core.c:rq_init()
 * as well!
L
Linus Torvalds 已提交
157 158
 */
struct request {
159
	struct list_head queuelist;
160 161
	struct call_single_data csd;
	int cpu;
162

163
	struct request_queue *q;
164

165 166
	unsigned int cmd_flags;
	enum rq_cmd_type_bits cmd_type;
J
Jens Axboe 已提交
167
	unsigned long atomic_flags;
L
Linus Torvalds 已提交
168

169 170 171
	/* the following two fields are internal, NEVER access directly */
	sector_t __sector;		/* sector cursor */
	unsigned int __data_len;	/* total data len */
L
Linus Torvalds 已提交
172 173 174 175

	struct bio *bio;
	struct bio *biotail;

176
	struct hlist_node hash;	/* merge hash */
177 178 179 180 181 182 183 184 185
	/*
	 * The rb_node is only used inside the io scheduler, requests
	 * are pruned when moved to the dispatch queue. So let the
	 * completion_data share space with the rb_node.
	 */
	union {
		struct rb_node rb_node;	/* sort/lookup */
		void *completion_data;
	};
186

187 188 189 190
	/*
	 * two pointers are available for the IO schedulers, if they need
	 * more they have to dynamically allocate it.
	 */
L
Linus Torvalds 已提交
191
	void *elevator_private;
192 193
	void *elevator_private2;

194
	struct gendisk *rq_disk;
L
Linus Torvalds 已提交
195 196 197 198 199 200 201
	unsigned long start_time;

	/* Number of scatter-gather DMA addr+len pairs after
	 * physical address coalescing is performed.
	 */
	unsigned short nr_phys_segments;

202 203
	unsigned short ioprio;

T
Tejun Heo 已提交
204 205
	void *special;		/* opaque pointer available for LLD use */
	char *buffer;		/* kaddr of the current segment if available */
L
Linus Torvalds 已提交
206

207 208 209 210 211
	int tag;
	int errors;

	int ref_count;

L
Linus Torvalds 已提交
212 213 214
	/*
	 * when request is used as a packet command carrier
	 */
215 216 217
	unsigned short cmd_len;
	unsigned char __cmd[BLK_MAX_CDB];
	unsigned char *cmd;
L
Linus Torvalds 已提交
218

219
	unsigned int extra_len;	/* length of alignment and padding */
L
Linus Torvalds 已提交
220
	unsigned int sense_len;
T
Tejun Heo 已提交
221
	unsigned int resid_len;	/* residual count */
L
Linus Torvalds 已提交
222 223
	void *sense;

J
Jens Axboe 已提交
224 225
	unsigned long deadline;
	struct list_head timeout_list;
L
Linus Torvalds 已提交
226
	unsigned int timeout;
227
	int retries;
L
Linus Torvalds 已提交
228 229

	/*
230
	 * completion callback.
L
Linus Torvalds 已提交
231 232 233
	 */
	rq_end_io_fn *end_io;
	void *end_io_data;
234 235 236

	/* for bidi */
	struct request *next_rq;
L
Linus Torvalds 已提交
237 238
};

239 240 241 242 243
static inline unsigned short req_get_ioprio(struct request *req)
{
	return req->ioprio;
}

L
Linus Torvalds 已提交
244
/*
245
 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
L
Linus Torvalds 已提交
246 247 248 249 250 251 252 253 254 255 256 257 258
 * requests. Some step values could eventually be made generic.
 */
struct request_pm_state
{
	/* PM state machine step value, currently driver specific */
	int	pm_step;
	/* requested PM state value (S1, S2, S3, S4, ...) */
	u32	pm_state;
	void*	data;		/* for driver use */
};

#include <linux/elevator.h>

259 260 261 262
typedef void (request_fn_proc) (struct request_queue *q);
typedef int (make_request_fn) (struct request_queue *q, struct bio *bio);
typedef int (prep_rq_fn) (struct request_queue *, struct request *);
typedef void (unplug_fn) (struct request_queue *);
L
Linus Torvalds 已提交
263 264

struct bio_vec;
265 266 267 268 269 270 271 272
struct bvec_merge_data {
	struct block_device *bi_bdev;
	sector_t bi_sector;
	unsigned bi_size;
	unsigned long bi_rw;
};
typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *,
			     struct bio_vec *);
273
typedef void (prepare_flush_fn) (struct request_queue *, struct request *);
274
typedef void (softirq_done_fn)(struct request *);
275
typedef int (dma_drain_needed_fn)(struct request *);
276
typedef int (lld_busy_fn) (struct request_queue *q);
L
Linus Torvalds 已提交
277

J
Jens Axboe 已提交
278 279 280 281 282 283 284 285
enum blk_eh_timer_return {
	BLK_EH_NOT_HANDLED,
	BLK_EH_HANDLED,
	BLK_EH_RESET_TIMER,
};

typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);

L
Linus Torvalds 已提交
286 287 288 289 290 291 292 293 294 295
enum blk_queue_state {
	Queue_down,
	Queue_up,
};

struct blk_queue_tag {
	struct request **tag_index;	/* map of busy tags */
	unsigned long *tag_map;		/* bit map of free/busy tags */
	int busy;			/* current depth */
	int max_depth;			/* what we will send to device */
296
	int real_max_depth;		/* what the array can hold */
L
Linus Torvalds 已提交
297 298 299
	atomic_t refcnt;		/* map can be shared */
};

300 301 302
#define BLK_SCSI_MAX_CMDS	(256)
#define BLK_SCSI_CMD_PER_LONG	(BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))

303 304 305 306 307 308 309
struct queue_limits {
	unsigned long		bounce_pfn;
	unsigned long		seg_boundary_mask;

	unsigned int		max_hw_sectors;
	unsigned int		max_sectors;
	unsigned int		max_segment_size;
310 311 312 313
	unsigned int		physical_block_size;
	unsigned int		alignment_offset;
	unsigned int		io_min;
	unsigned int		io_opt;
314
	unsigned int		max_discard_sectors;
315 316
	unsigned int		discard_granularity;
	unsigned int		discard_alignment;
317 318 319 320 321

	unsigned short		logical_block_size;
	unsigned short		max_hw_segments;
	unsigned short		max_phys_segments;

322
	unsigned char		misaligned;
323
	unsigned char		discard_misaligned;
324
	unsigned char		no_cluster;
325
	signed char		discard_zeroes_data;
326 327
};

L
Linus Torvalds 已提交
328 329 330 331 332 333 334
struct request_queue
{
	/*
	 * Together with queue_head for cacheline sharing
	 */
	struct list_head	queue_head;
	struct request		*last_merge;
J
Jens Axboe 已提交
335
	struct elevator_queue	*elevator;
L
Linus Torvalds 已提交
336 337 338 339 340 341 342 343 344 345 346 347

	/*
	 * the queue request freelist, one for reads and one for writes
	 */
	struct request_list	rq;

	request_fn_proc		*request_fn;
	make_request_fn		*make_request_fn;
	prep_rq_fn		*prep_rq_fn;
	unplug_fn		*unplug_fn;
	merge_bvec_fn		*merge_bvec_fn;
	prepare_flush_fn	*prepare_flush_fn;
348
	softirq_done_fn		*softirq_done_fn;
J
Jens Axboe 已提交
349
	rq_timed_out_fn		*rq_timed_out_fn;
350
	dma_drain_needed_fn	*dma_drain_needed;
351
	lld_busy_fn		*lld_busy_fn;
L
Linus Torvalds 已提交
352

353 354 355
	/*
	 * Dispatch queue sorting
	 */
J
Jens Axboe 已提交
356
	sector_t		end_sector;
357 358
	struct request		*boundary_rq;

L
Linus Torvalds 已提交
359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377
	/*
	 * Auto-unplugging state
	 */
	struct timer_list	unplug_timer;
	int			unplug_thresh;	/* After this many requests */
	unsigned long		unplug_delay;	/* After this many jiffies */
	struct work_struct	unplug_work;

	struct backing_dev_info	backing_dev_info;

	/*
	 * The queue owner gets to use this for whatever they like.
	 * ll_rw_blk doesn't touch it.
	 */
	void			*queuedata;

	/*
	 * queue needs bounce pages for pages above this limit
	 */
A
Al Viro 已提交
378
	gfp_t			bounce_gfp;
L
Linus Torvalds 已提交
379 380 381 382 383 384 385

	/*
	 * various queue flags, see QUEUE_* below
	 */
	unsigned long		queue_flags;

	/*
已提交
386 387 388
	 * protects queue structures from reentrancy. ->__queue_lock should
	 * _never_ be used directly, it is queue private. always use
	 * ->queue_lock.
L
Linus Torvalds 已提交
389
	 */
已提交
390
	spinlock_t		__queue_lock;
L
Linus Torvalds 已提交
391 392 393 394 395 396 397 398 399 400 401 402 403 404 405
	spinlock_t		*queue_lock;

	/*
	 * queue kobject
	 */
	struct kobject kobj;

	/*
	 * queue settings
	 */
	unsigned long		nr_requests;	/* Max # of requests */
	unsigned int		nr_congestion_on;
	unsigned int		nr_congestion_off;
	unsigned int		nr_batching;

J
James Bottomley 已提交
406 407
	void			*dma_drain_buffer;
	unsigned int		dma_drain_size;
408
	unsigned int		dma_pad_mask;
L
Linus Torvalds 已提交
409 410 411
	unsigned int		dma_alignment;

	struct blk_queue_tag	*queue_tags;
412
	struct list_head	tag_busy_list;
L
Linus Torvalds 已提交
413

414
	unsigned int		nr_sorted;
415
	unsigned int		in_flight[2];
L
Linus Torvalds 已提交
416

J
Jens Axboe 已提交
417 418 419 420
	unsigned int		rq_timeout;
	struct timer_list	timeout;
	struct list_head	timeout_list;

421 422
	struct queue_limits	limits;

L
Linus Torvalds 已提交
423 424 425 426 427
	/*
	 * sg stuff
	 */
	unsigned int		sg_timeout;
	unsigned int		sg_reserved_size;
428
	int			node;
429
#ifdef CONFIG_BLK_DEV_IO_TRACE
430
	struct blk_trace	*blk_trace;
431
#endif
L
Linus Torvalds 已提交
432 433 434
	/*
	 * reserved for flush operations
	 */
435 436 437 438
	unsigned int		ordered, next_ordered, ordseq;
	int			orderr, ordcolor;
	struct request		pre_flush_rq, bar_rq, post_flush_rq;
	struct request		*orig_bar_rq;
439 440

	struct mutex		sysfs_lock;
441 442 443 444

#if defined(CONFIG_BLK_DEV_BSG)
	struct bsg_class_device bsg_dev;
#endif
L
Linus Torvalds 已提交
445 446 447 448 449
};

#define QUEUE_FLAG_CLUSTER	0	/* cluster several segments into 1 */
#define QUEUE_FLAG_QUEUED	1	/* uses generic tag queueing */
#define QUEUE_FLAG_STOPPED	2	/* queue is stopped */
450 451
#define	QUEUE_FLAG_SYNCFULL	3	/* read queue has been filled */
#define QUEUE_FLAG_ASYNCFULL	4	/* write queue has been filled */
L
Linus Torvalds 已提交
452 453 454
#define QUEUE_FLAG_DEAD		5	/* queue being torn down */
#define QUEUE_FLAG_REENTER	6	/* Re-entrancy avoidance */
#define QUEUE_FLAG_PLUGGED	7	/* queue is plugged */
J
Jens Axboe 已提交
455
#define QUEUE_FLAG_ELVSWITCH	8	/* don't use elevator, just do FIFO */
456
#define QUEUE_FLAG_BIDI		9	/* queue supports bidi requests */
457
#define QUEUE_FLAG_NOMERGES    10	/* disable merge attempts */
458
#define QUEUE_FLAG_SAME_COMP   11	/* force complete on same CPU */
459
#define QUEUE_FLAG_FAIL_IO     12	/* fake timeout */
460
#define QUEUE_FLAG_STACKABLE   13	/* supports request stacking */
461
#define QUEUE_FLAG_NONROT      14	/* non-rotational device (SSD) */
462
#define QUEUE_FLAG_VIRT        QUEUE_FLAG_NONROT /* paravirt device */
463
#define QUEUE_FLAG_IO_STAT     15	/* do IO stats */
464
#define QUEUE_FLAG_CQ	       16	/* hardware does queuing */
465
#define QUEUE_FLAG_DISCARD     17	/* supports DISCARD */
466 467 468

#define QUEUE_FLAG_DEFAULT	((1 << QUEUE_FLAG_IO_STAT) |		\
				 (1 << QUEUE_FLAG_CLUSTER) |		\
469 470
				 (1 << QUEUE_FLAG_STACKABLE)	|	\
				 (1 << QUEUE_FLAG_SAME_COMP))
471

472 473
static inline int queue_is_locked(struct request_queue *q)
{
J
Jens Axboe 已提交
474
#ifdef CONFIG_SMP
475 476
	spinlock_t *lock = q->queue_lock;
	return lock && spin_is_locked(lock);
J
Jens Axboe 已提交
477 478 479
#else
	return 1;
#endif
480 481
}

N
Nick Piggin 已提交
482 483 484 485 486 487
static inline void queue_flag_set_unlocked(unsigned int flag,
					   struct request_queue *q)
{
	__set_bit(flag, &q->queue_flags);
}

J
Jens Axboe 已提交
488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513
static inline int queue_flag_test_and_clear(unsigned int flag,
					    struct request_queue *q)
{
	WARN_ON_ONCE(!queue_is_locked(q));

	if (test_bit(flag, &q->queue_flags)) {
		__clear_bit(flag, &q->queue_flags);
		return 1;
	}

	return 0;
}

static inline int queue_flag_test_and_set(unsigned int flag,
					  struct request_queue *q)
{
	WARN_ON_ONCE(!queue_is_locked(q));

	if (!test_bit(flag, &q->queue_flags)) {
		__set_bit(flag, &q->queue_flags);
		return 0;
	}

	return 1;
}

N
Nick Piggin 已提交
514 515
static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
{
516
	WARN_ON_ONCE(!queue_is_locked(q));
N
Nick Piggin 已提交
517 518 519 520 521 522 523 524 525
	__set_bit(flag, &q->queue_flags);
}

static inline void queue_flag_clear_unlocked(unsigned int flag,
					     struct request_queue *q)
{
	__clear_bit(flag, &q->queue_flags);
}

526 527 528 529 530
static inline int queue_in_flight(struct request_queue *q)
{
	return q->in_flight[0] + q->in_flight[1];
}

N
Nick Piggin 已提交
531 532
static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
{
533
	WARN_ON_ONCE(!queue_is_locked(q));
N
Nick Piggin 已提交
534 535 536
	__clear_bit(flag, &q->queue_flags);
}

537 538 539 540 541 542 543 544 545 546 547 548
enum {
	/*
	 * Hardbarrier is supported with one of the following methods.
	 *
	 * NONE		: hardbarrier unsupported
	 * DRAIN	: ordering by draining is enough
	 * DRAIN_FLUSH	: ordering by draining w/ pre and post flushes
	 * DRAIN_FUA	: ordering by draining w/ pre flush and FUA write
	 * TAG		: ordering by tag is enough
	 * TAG_FLUSH	: ordering by tag w/ pre and post flushes
	 * TAG_FUA	: ordering by tag w/ pre flush and FUA write
	 */
549 550 551
	QUEUE_ORDERED_BY_DRAIN		= 0x01,
	QUEUE_ORDERED_BY_TAG		= 0x02,
	QUEUE_ORDERED_DO_PREFLUSH	= 0x10,
552
	QUEUE_ORDERED_DO_BAR		= 0x20,
553 554 555 556 557
	QUEUE_ORDERED_DO_POSTFLUSH	= 0x40,
	QUEUE_ORDERED_DO_FUA		= 0x80,

	QUEUE_ORDERED_NONE		= 0x00,

558 559
	QUEUE_ORDERED_DRAIN		= QUEUE_ORDERED_BY_DRAIN |
					  QUEUE_ORDERED_DO_BAR,
560 561 562 563 564 565 566
	QUEUE_ORDERED_DRAIN_FLUSH	= QUEUE_ORDERED_DRAIN |
					  QUEUE_ORDERED_DO_PREFLUSH |
					  QUEUE_ORDERED_DO_POSTFLUSH,
	QUEUE_ORDERED_DRAIN_FUA		= QUEUE_ORDERED_DRAIN |
					  QUEUE_ORDERED_DO_PREFLUSH |
					  QUEUE_ORDERED_DO_FUA,

567 568
	QUEUE_ORDERED_TAG		= QUEUE_ORDERED_BY_TAG |
					  QUEUE_ORDERED_DO_BAR,
569 570 571 572 573 574
	QUEUE_ORDERED_TAG_FLUSH		= QUEUE_ORDERED_TAG |
					  QUEUE_ORDERED_DO_PREFLUSH |
					  QUEUE_ORDERED_DO_POSTFLUSH,
	QUEUE_ORDERED_TAG_FUA		= QUEUE_ORDERED_TAG |
					  QUEUE_ORDERED_DO_PREFLUSH |
					  QUEUE_ORDERED_DO_FUA,
575 576 577 578 579 580 581 582 583 584 585

	/*
	 * Ordered operation sequence
	 */
	QUEUE_ORDSEQ_STARTED	= 0x01,	/* flushing in progress */
	QUEUE_ORDSEQ_DRAIN	= 0x02,	/* waiting for the queue to be drained */
	QUEUE_ORDSEQ_PREFLUSH	= 0x04,	/* pre-flushing in progress */
	QUEUE_ORDSEQ_BAR	= 0x08,	/* original barrier req in progress */
	QUEUE_ORDSEQ_POSTFLUSH	= 0x10,	/* post-flushing in progress */
	QUEUE_ORDSEQ_DONE	= 0x20,
};
L
Linus Torvalds 已提交
586 587 588

#define blk_queue_plugged(q)	test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags)
#define blk_queue_tagged(q)	test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
589
#define blk_queue_queuing(q)	test_bit(QUEUE_FLAG_CQ, &(q)->queue_flags)
L
Linus Torvalds 已提交
590
#define blk_queue_stopped(q)	test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
591
#define blk_queue_nomerges(q)	test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
592
#define blk_queue_nonrot(q)	test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
593
#define blk_queue_io_stat(q)	test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
594
#define blk_queue_flushing(q)	((q)->ordseq)
595 596
#define blk_queue_stackable(q)	\
	test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
597
#define blk_queue_discard(q)	test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
L
Linus Torvalds 已提交
598

599 600 601 602 603
#define blk_fs_request(rq)	((rq)->cmd_type == REQ_TYPE_FS)
#define blk_pc_request(rq)	((rq)->cmd_type == REQ_TYPE_BLOCK_PC)
#define blk_special_request(rq)	((rq)->cmd_type == REQ_TYPE_SPECIAL)
#define blk_sense_request(rq)	((rq)->cmd_type == REQ_TYPE_SENSE)

604 605 606 607 608 609
#define blk_failfast_dev(rq)	((rq)->cmd_flags & REQ_FAILFAST_DEV)
#define blk_failfast_transport(rq) ((rq)->cmd_flags & REQ_FAILFAST_TRANSPORT)
#define blk_failfast_driver(rq)	((rq)->cmd_flags & REQ_FAILFAST_DRIVER)
#define blk_noretry_request(rq)	(blk_failfast_dev(rq) ||	\
				 blk_failfast_transport(rq) ||	\
				 blk_failfast_driver(rq))
610
#define blk_rq_started(rq)	((rq)->cmd_flags & REQ_STARTED)
611
#define blk_rq_io_stat(rq)	((rq)->cmd_flags & REQ_IO_STAT)
612
#define blk_rq_quiet(rq)	((rq)->cmd_flags & REQ_QUIET)
L
Linus Torvalds 已提交
613

614
#define blk_account_rq(rq)	(blk_rq_started(rq) && (blk_fs_request(rq) || blk_discard_rq(rq))) 
L
Linus Torvalds 已提交
615

616 617
#define blk_pm_suspend_request(rq)	((rq)->cmd_type == REQ_TYPE_PM_SUSPEND)
#define blk_pm_resume_request(rq)	((rq)->cmd_type == REQ_TYPE_PM_RESUME)
L
Linus Torvalds 已提交
618
#define blk_pm_request(rq)	\
619
	(blk_pm_suspend_request(rq) || blk_pm_resume_request(rq))
L
Linus Torvalds 已提交
620

621
#define blk_rq_cpu_valid(rq)	((rq)->cpu != -1)
622 623 624
#define blk_sorted_rq(rq)	((rq)->cmd_flags & REQ_SORTED)
#define blk_barrier_rq(rq)	((rq)->cmd_flags & REQ_HARDBARRIER)
#define blk_fua_rq(rq)		((rq)->cmd_flags & REQ_FUA)
D
David Woodhouse 已提交
625
#define blk_discard_rq(rq)	((rq)->cmd_flags & REQ_DISCARD)
626
#define blk_bidi_rq(rq)		((rq)->next_rq != NULL)
627 628
/* rq->queuelist of dequeued request must be list_empty() */
#define blk_queued_rq(rq)	(!list_empty(&(rq)->queuelist))
L
Linus Torvalds 已提交
629 630 631

#define list_entry_rq(ptr)	list_entry((ptr), struct request, queuelist)

632
#define rq_data_dir(rq)		((rq)->cmd_flags & 1)
L
Linus Torvalds 已提交
633

634
/*
635
 * We regard a request as sync, if either a read or a sync write
636
 */
637 638 639 640 641 642 643 644 645 646
static inline bool rw_is_sync(unsigned int rw_flags)
{
	return !(rw_flags & REQ_RW) || (rw_flags & REQ_RW_SYNC);
}

static inline bool rq_is_sync(struct request *rq)
{
	return rw_is_sync(rq->cmd_flags);
}

647
#define rq_is_meta(rq)		((rq)->cmd_flags & REQ_RW_META)
648
#define rq_noidle(rq)		((rq)->cmd_flags & REQ_NOIDLE)
649

650
static inline int blk_queue_full(struct request_queue *q, int sync)
L
Linus Torvalds 已提交
651
{
652 653 654
	if (sync)
		return test_bit(QUEUE_FLAG_SYNCFULL, &q->queue_flags);
	return test_bit(QUEUE_FLAG_ASYNCFULL, &q->queue_flags);
L
Linus Torvalds 已提交
655 656
}

657
static inline void blk_set_queue_full(struct request_queue *q, int sync)
L
Linus Torvalds 已提交
658
{
659 660
	if (sync)
		queue_flag_set(QUEUE_FLAG_SYNCFULL, q);
L
Linus Torvalds 已提交
661
	else
662
		queue_flag_set(QUEUE_FLAG_ASYNCFULL, q);
L
Linus Torvalds 已提交
663 664
}

665
static inline void blk_clear_queue_full(struct request_queue *q, int sync)
L
Linus Torvalds 已提交
666
{
667 668
	if (sync)
		queue_flag_clear(QUEUE_FLAG_SYNCFULL, q);
L
Linus Torvalds 已提交
669
	else
670
		queue_flag_clear(QUEUE_FLAG_ASYNCFULL, q);
L
Linus Torvalds 已提交
671 672 673 674 675 676 677 678 679 680
}


/*
 * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may
 * it already be started by driver.
 */
#define RQ_NOMERGE_FLAGS	\
	(REQ_NOMERGE | REQ_STARTED | REQ_HARDBARRIER | REQ_SOFTBARRIER)
#define rq_mergeable(rq)	\
681 682
	(!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \
	 (blk_discard_rq(rq) || blk_fs_request((rq))))
L
Linus Torvalds 已提交
683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699

/*
 * q->prep_rq_fn return values
 */
#define BLKPREP_OK		0	/* serve it */
#define BLKPREP_KILL		1	/* fatal error, kill */
#define BLKPREP_DEFER		2	/* leave on queue */

extern unsigned long blk_max_low_pfn, blk_max_pfn;

/*
 * standard bounce addresses:
 *
 * BLK_BOUNCE_HIGH	: bounce all highmem pages
 * BLK_BOUNCE_ANY	: don't bounce anything
 * BLK_BOUNCE_ISA	: bounce pages above ISA DMA boundary
 */
700 701

#if BITS_PER_LONG == 32
L
Linus Torvalds 已提交
702
#define BLK_BOUNCE_HIGH		((u64)blk_max_low_pfn << PAGE_SHIFT)
703 704 705 706
#else
#define BLK_BOUNCE_HIGH		-1ULL
#endif
#define BLK_BOUNCE_ANY		(-1ULL)
L
Linus Torvalds 已提交
707 708
#define BLK_BOUNCE_ISA		(ISA_DMA_THRESHOLD)

709 710 711 712
/*
 * default timeout for SG_IO if none specified
 */
#define BLK_DEFAULT_SG_TIMEOUT	(60 * HZ)
L
Linus Torvalds 已提交
713
#define BLK_MIN_SG_TIMEOUT	(7 * HZ)
714

715
#ifdef CONFIG_BOUNCE
L
Linus Torvalds 已提交
716
extern int init_emergency_isa_pool(void);
717
extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
L
Linus Torvalds 已提交
718 719 720 721 722
#else
static inline int init_emergency_isa_pool(void)
{
	return 0;
}
723
static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
L
Linus Torvalds 已提交
724 725 726 727
{
}
#endif /* CONFIG_MMU */

728 729 730 731
struct rq_map_data {
	struct page **pages;
	int page_order;
	int nr_entries;
732
	unsigned long offset;
733
	int null_mapped;
734
	int from_user;
735 736
};

737 738 739 740 741 742
struct req_iterator {
	int i;
	struct bio *bio;
};

/* This should not be used directly - use rq_for_each_segment */
743 744
#define for_each_bio(_bio)		\
	for (; _bio; _bio = _bio->bi_next)
745
#define __rq_for_each_bio(_bio, rq)	\
L
Linus Torvalds 已提交
746 747 748
	if ((rq->bio))			\
		for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)

749 750 751 752 753 754 755
#define rq_for_each_segment(bvl, _rq, _iter)			\
	__rq_for_each_bio(_iter.bio, _rq)			\
		bio_for_each_segment(bvl, _iter.bio, _iter.i)

#define rq_iter_last(rq, _iter)					\
		(_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1)

756 757 758 759 760 761 762 763 764 765 766
#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
# error	"You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
#endif
#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
extern void rq_flush_dcache_pages(struct request *rq);
#else
static inline void rq_flush_dcache_pages(struct request *rq)
{
}
#endif

L
Linus Torvalds 已提交
767 768 769 770
extern int blk_register_queue(struct gendisk *disk);
extern void blk_unregister_queue(struct gendisk *disk);
extern void register_disk(struct gendisk *dev);
extern void generic_make_request(struct bio *bio);
771
extern void blk_rq_init(struct request_queue *q, struct request *rq);
L
Linus Torvalds 已提交
772
extern void blk_put_request(struct request *);
773 774
extern void __blk_put_request(struct request_queue *, struct request *);
extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
775 776
extern struct request *blk_make_request(struct request_queue *, struct bio *,
					gfp_t);
777 778
extern void blk_insert_request(struct request_queue *, struct request *, int, void *);
extern void blk_requeue_request(struct request_queue *, struct request *);
779
extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
780
extern int blk_lld_busy(struct request_queue *q);
781 782 783 784 785
extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
			     struct bio_set *bs, gfp_t gfp_mask,
			     int (*bio_ctr)(struct bio *, struct bio *, void *),
			     void *data);
extern void blk_rq_unprep_clone(struct request *rq);
786 787
extern int blk_insert_cloned_request(struct request_queue *q,
				     struct request *rq);
788
extern void blk_plug_device(struct request_queue *);
789
extern void blk_plug_device_unlocked(struct request_queue *);
790 791
extern int blk_remove_plug(struct request_queue *);
extern void blk_recount_segments(struct request_queue *, struct bio *);
792 793
extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
			  unsigned int, void __user *);
794 795
extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
			 struct scsi_ioctl_command __user *);
796 797 798 799 800 801

/*
 * A queue has just exitted congestion.  Note this in the global counter of
 * congested queues, and wake up anyone who was waiting for requests to be
 * put back.
 */
802
static inline void blk_clear_queue_congested(struct request_queue *q, int sync)
803
{
804
	clear_bdi_congested(&q->backing_dev_info, sync);
805 806 807 808 809 810
}

/*
 * A queue has just entered congestion.  Flag that in the queue's VM-visible
 * state flags and increment the global gounter of congested queues.
 */
811
static inline void blk_set_queue_congested(struct request_queue *q, int sync)
812
{
813
	set_bdi_congested(&q->backing_dev_info, sync);
814 815
}

816 817
extern void blk_start_queue(struct request_queue *q);
extern void blk_stop_queue(struct request_queue *q);
L
Linus Torvalds 已提交
818
extern void blk_sync_queue(struct request_queue *q);
819
extern void __blk_stop_queue(struct request_queue *q);
N
Nick Piggin 已提交
820
extern void __blk_run_queue(struct request_queue *);
821
extern void blk_run_queue(struct request_queue *);
822
extern int blk_rq_map_user(struct request_queue *, struct request *,
823 824
			   struct rq_map_data *, void __user *, unsigned long,
			   gfp_t);
J
Jens Axboe 已提交
825
extern int blk_rq_unmap_user(struct bio *);
826 827
extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
828 829
			       struct rq_map_data *, struct sg_iovec *, int,
			       unsigned int, gfp_t);
830
extern int blk_execute_rq(struct request_queue *, struct gendisk *,
831
			  struct request *, int);
832
extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
833
				  struct request *, int, rq_end_io_fn *);
834
extern void blk_unplug(struct request_queue *q);
835

836
static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
L
Linus Torvalds 已提交
837 838 839 840
{
	return bdev->bd_disk->queue;
}

841
/*
842 843 844 845 846 847
 * blk_rq_pos()			: the current sector
 * blk_rq_bytes()		: bytes left in the entire request
 * blk_rq_cur_bytes()		: bytes left in the current segment
 * blk_rq_err_bytes()		: bytes left till the next error boundary
 * blk_rq_sectors()		: sectors left in the entire request
 * blk_rq_cur_sectors()		: sectors left in the current segment
848
 */
849 850
static inline sector_t blk_rq_pos(const struct request *rq)
{
851
	return rq->__sector;
852 853 854 855
}

static inline unsigned int blk_rq_bytes(const struct request *rq)
{
856
	return rq->__data_len;
857 858
}

859 860 861 862
static inline int blk_rq_cur_bytes(const struct request *rq)
{
	return rq->bio ? bio_cur_bytes(rq->bio) : 0;
}
863

864 865
extern unsigned int blk_rq_err_bytes(const struct request *rq);

866 867
static inline unsigned int blk_rq_sectors(const struct request *rq)
{
868
	return blk_rq_bytes(rq) >> 9;
869 870 871 872
}

static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
{
873
	return blk_rq_cur_bytes(rq) >> 9;
874 875
}

876 877 878 879 880 881 882
/*
 * Request issue related functions.
 */
extern struct request *blk_peek_request(struct request_queue *q);
extern void blk_start_request(struct request *rq);
extern struct request *blk_fetch_request(struct request_queue *q);

L
Linus Torvalds 已提交
883
/*
884 885 886 887 888
 * Request completion related functions.
 *
 * blk_update_request() completes given number of bytes and updates
 * the request without completing it.
 *
889 890
 * blk_end_request() and friends.  __blk_end_request() must be called
 * with the request queue spinlock acquired.
L
Linus Torvalds 已提交
891 892
 *
 * Several drivers define their own end_request and call
893 894
 * blk_end_request() for parts of the original function.
 * This prevents code duplication in drivers.
L
Linus Torvalds 已提交
895
 */
896 897
extern bool blk_update_request(struct request *rq, int error,
			       unsigned int nr_bytes);
898 899 900 901
extern bool blk_end_request(struct request *rq, int error,
			    unsigned int nr_bytes);
extern void blk_end_request_all(struct request *rq, int error);
extern bool blk_end_request_cur(struct request *rq, int error);
902
extern bool blk_end_request_err(struct request *rq, int error);
903 904 905 906
extern bool __blk_end_request(struct request *rq, int error,
			      unsigned int nr_bytes);
extern void __blk_end_request_all(struct request *rq, int error);
extern bool __blk_end_request_cur(struct request *rq, int error);
907
extern bool __blk_end_request_err(struct request *rq, int error);
908

909
extern void blk_complete_request(struct request *);
J
Jens Axboe 已提交
910 911
extern void __blk_complete_request(struct request *);
extern void blk_abort_request(struct request *);
912
extern void blk_abort_queue(struct request_queue *);
913

L
Linus Torvalds 已提交
914 915 916
/*
 * Access functions for manipulating queue properties
 */
917
extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
918
					spinlock_t *lock, int node_id);
919 920 921 922 923
extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
extern void blk_cleanup_queue(struct request_queue *);
extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
extern void blk_queue_bounce_limit(struct request_queue *, u64);
extern void blk_queue_max_sectors(struct request_queue *, unsigned int);
924
extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
925 926 927
extern void blk_queue_max_phys_segments(struct request_queue *, unsigned short);
extern void blk_queue_max_hw_segments(struct request_queue *, unsigned short);
extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
928 929
extern void blk_queue_max_discard_sectors(struct request_queue *q,
		unsigned int max_discard_sectors);
930
extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
931 932 933
extern void blk_queue_physical_block_size(struct request_queue *, unsigned short);
extern void blk_queue_alignment_offset(struct request_queue *q,
				       unsigned int alignment);
934
extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
935
extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
936
extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
937
extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
938
extern void blk_set_default_limits(struct queue_limits *lim);
939 940 941 942
extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
			    sector_t offset);
extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
			      sector_t offset);
943
extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
944
extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
945
extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
946 947 948
extern int blk_queue_dma_drain(struct request_queue *q,
			       dma_drain_needed_fn *dma_drain_needed,
			       void *buf, unsigned int size);
949
extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
950 951 952 953
extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *);
extern void blk_queue_dma_alignment(struct request_queue *, int);
954
extern void blk_queue_update_dma_alignment(struct request_queue *, int);
955
extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
J
Jens Axboe 已提交
956 957
extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
L
Linus Torvalds 已提交
958
extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
959
extern int blk_queue_ordered(struct request_queue *, unsigned, prepare_flush_fn *);
960
extern bool blk_do_ordered(struct request_queue *, struct request **);
961
extern unsigned blk_ordered_cur_seq(struct request_queue *);
962
extern unsigned blk_ordered_req_seq(struct request *);
963
extern bool blk_ordered_complete_seq(struct request_queue *, unsigned, int);
L
Linus Torvalds 已提交
964

965
extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
L
Linus Torvalds 已提交
966
extern void blk_dump_rq_flags(struct request *, char *);
967
extern void generic_unplug_device(struct request_queue *);
L
Linus Torvalds 已提交
968 969
extern long nr_blockdev_pages(void);

970 971 972 973
int blk_get_queue(struct request_queue *);
struct request_queue *blk_alloc_queue(gfp_t);
struct request_queue *blk_alloc_queue_node(gfp_t, int);
extern void blk_put_queue(struct request_queue *);
L
Linus Torvalds 已提交
974 975 976 977

/*
 * tag stuff
 */
978
#define blk_rq_tagged(rq)		((rq)->cmd_flags & REQ_QUEUED)
979 980 981 982 983 984 985
extern int blk_queue_start_tag(struct request_queue *, struct request *);
extern struct request *blk_queue_find_tag(struct request_queue *, int);
extern void blk_queue_end_tag(struct request_queue *, struct request *);
extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *);
extern void blk_queue_free_tags(struct request_queue *);
extern int blk_queue_resize_tags(struct request_queue *, int);
extern void blk_queue_invalidate_tags(struct request_queue *);
986 987
extern struct blk_queue_tag *blk_init_tags(int);
extern void blk_free_tags(struct blk_queue_tag *);
L
Linus Torvalds 已提交
988

989 990 991 992 993 994 995 996
static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
						int tag)
{
	if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
		return NULL;
	return bqt->tag_index[tag];
}

L
Linus Torvalds 已提交
997
extern int blkdev_issue_flush(struct block_device *, sector_t *);
998 999 1000 1001
#define DISCARD_FL_WAIT		0x01	/* wait for completion */
#define DISCARD_FL_BARRIER	0x02	/* issue DISCARD_BARRIER request */
extern int blkdev_issue_discard(struct block_device *, sector_t sector,
		sector_t nr_sects, gfp_t, int flags);
D
David Woodhouse 已提交
1002 1003

static inline int sb_issue_discard(struct super_block *sb,
1004
				   sector_t block, sector_t nr_blocks)
D
David Woodhouse 已提交
1005 1006 1007
{
	block <<= (sb->s_blocksize_bits - 9);
	nr_blocks <<= (sb->s_blocksize_bits - 9);
1008 1009
	return blkdev_issue_discard(sb->s_bdev, block, nr_blocks, GFP_KERNEL,
				    DISCARD_FL_BARRIER);
D
David Woodhouse 已提交
1010
}
L
Linus Torvalds 已提交
1011

1012
extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
1013

L
Linus Torvalds 已提交
1014 1015
#define MAX_PHYS_SEGMENTS 128
#define MAX_HW_SEGMENTS 128
1016 1017
#define SAFE_MAX_SECTORS 255
#define BLK_DEF_MAX_SECTORS 1024
L
Linus Torvalds 已提交
1018 1019 1020

#define MAX_SEGMENT_SIZE	65536

1021 1022
#define BLK_SEG_BOUNDARY_MASK	0xFFFFFFFFUL

L
Linus Torvalds 已提交
1023 1024
#define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)

1025 1026
static inline unsigned long queue_bounce_pfn(struct request_queue *q)
{
1027
	return q->limits.bounce_pfn;
1028 1029 1030 1031
}

static inline unsigned long queue_segment_boundary(struct request_queue *q)
{
1032
	return q->limits.seg_boundary_mask;
1033 1034 1035 1036
}

static inline unsigned int queue_max_sectors(struct request_queue *q)
{
1037
	return q->limits.max_sectors;
1038 1039 1040 1041
}

static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
{
1042
	return q->limits.max_hw_sectors;
1043 1044 1045 1046
}

static inline unsigned short queue_max_hw_segments(struct request_queue *q)
{
1047
	return q->limits.max_hw_segments;
1048 1049 1050 1051
}

static inline unsigned short queue_max_phys_segments(struct request_queue *q)
{
1052
	return q->limits.max_phys_segments;
1053 1054 1055 1056
}

static inline unsigned int queue_max_segment_size(struct request_queue *q)
{
1057
	return q->limits.max_segment_size;
1058 1059
}

1060
static inline unsigned short queue_logical_block_size(struct request_queue *q)
L
Linus Torvalds 已提交
1061 1062 1063
{
	int retval = 512;

1064 1065
	if (q && q->limits.logical_block_size)
		retval = q->limits.logical_block_size;
L
Linus Torvalds 已提交
1066 1067 1068 1069

	return retval;
}

1070
static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
L
Linus Torvalds 已提交
1071
{
1072
	return queue_logical_block_size(bdev_get_queue(bdev));
L
Linus Torvalds 已提交
1073 1074
}

1075 1076 1077 1078 1079
static inline unsigned int queue_physical_block_size(struct request_queue *q)
{
	return q->limits.physical_block_size;
}

M
Martin K. Petersen 已提交
1080 1081 1082 1083 1084
static inline int bdev_physical_block_size(struct block_device *bdev)
{
	return queue_physical_block_size(bdev_get_queue(bdev));
}

1085 1086 1087 1088 1089
static inline unsigned int queue_io_min(struct request_queue *q)
{
	return q->limits.io_min;
}

M
Martin K. Petersen 已提交
1090 1091 1092 1093 1094
static inline int bdev_io_min(struct block_device *bdev)
{
	return queue_io_min(bdev_get_queue(bdev));
}

1095 1096 1097 1098 1099
static inline unsigned int queue_io_opt(struct request_queue *q)
{
	return q->limits.io_opt;
}

M
Martin K. Petersen 已提交
1100 1101 1102 1103 1104
static inline int bdev_io_opt(struct block_device *bdev)
{
	return queue_io_opt(bdev_get_queue(bdev));
}

1105 1106
static inline int queue_alignment_offset(struct request_queue *q)
{
M
Martin K. Petersen 已提交
1107
	if (q->limits.misaligned)
1108 1109
		return -1;

M
Martin K. Petersen 已提交
1110
	return q->limits.alignment_offset;
1111 1112
}

1113 1114 1115 1116 1117 1118 1119 1120
static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t offset)
{
	unsigned int granularity = max(lim->physical_block_size, lim->io_min);

	offset &= granularity - 1;
	return (granularity + lim->alignment_offset - offset) & (granularity - 1);
}

1121 1122 1123
static inline int queue_sector_alignment_offset(struct request_queue *q,
						sector_t sector)
{
1124
	return queue_limit_alignment_offset(&q->limits, sector << 9);
1125 1126
}

M
Martin K. Petersen 已提交
1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139
static inline int bdev_alignment_offset(struct block_device *bdev)
{
	struct request_queue *q = bdev_get_queue(bdev);

	if (q->limits.misaligned)
		return -1;

	if (bdev != bdev->bd_contains)
		return bdev->bd_part->alignment_offset;

	return q->limits.alignment_offset;
}

1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154
static inline int queue_discard_alignment(struct request_queue *q)
{
	if (q->limits.discard_misaligned)
		return -1;

	return q->limits.discard_alignment;
}

static inline int queue_sector_discard_alignment(struct request_queue *q,
						 sector_t sector)
{
	return ((sector << 9) - q->limits.discard_alignment)
		& (q->limits.discard_granularity - 1);
}

1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167
static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
{
	if (q->limits.discard_zeroes_data == 1)
		return 1;

	return 0;
}

static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
{
	return queue_discard_zeroes_data(bdev_get_queue(bdev));
}

1168
static inline int queue_dma_alignment(struct request_queue *q)
L
Linus Torvalds 已提交
1169
{
1170
	return q ? q->dma_alignment : 511;
L
Linus Torvalds 已提交
1171 1172
}

1173 1174 1175 1176 1177 1178 1179
static inline int blk_rq_aligned(struct request_queue *q, void *addr,
				 unsigned int len)
{
	unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
	return !((unsigned long)addr & alignment) && !(len & alignment);
}

L
Linus Torvalds 已提交
1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190
/* assumes size > 256 */
static inline unsigned int blksize_bits(unsigned int size)
{
	unsigned int bits = 8;
	do {
		bits++;
		size >>= 1;
	} while (size > 256);
	return bits;
}

1191
static inline unsigned int block_size(struct block_device *bdev)
L
Linus Torvalds 已提交
1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205
{
	return bdev->bd_block_size;
}

typedef struct {struct page *v;} Sector;

unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);

static inline void put_dev_sector(Sector p)
{
	page_cache_release(p.v);
}

struct work_struct;
1206
int kblockd_schedule_work(struct request_queue *q, struct work_struct *work);
L
Linus Torvalds 已提交
1207 1208 1209 1210 1211 1212

#define MODULE_ALIAS_BLOCKDEV(major,minor) \
	MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
#define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
	MODULE_ALIAS("block-major-" __stringify(major) "-*")

1213 1214
#if defined(CONFIG_BLK_DEV_INTEGRITY)

1215 1216
#define INTEGRITY_FLAG_READ	2	/* verify data integrity on read */
#define INTEGRITY_FLAG_WRITE	4	/* generate data integrity on write */
1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249

struct blk_integrity_exchg {
	void			*prot_buf;
	void			*data_buf;
	sector_t		sector;
	unsigned int		data_size;
	unsigned short		sector_size;
	const char		*disk_name;
};

typedef void (integrity_gen_fn) (struct blk_integrity_exchg *);
typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *);
typedef void (integrity_set_tag_fn) (void *, void *, unsigned int);
typedef void (integrity_get_tag_fn) (void *, void *, unsigned int);

struct blk_integrity {
	integrity_gen_fn	*generate_fn;
	integrity_vrfy_fn	*verify_fn;
	integrity_set_tag_fn	*set_tag_fn;
	integrity_get_tag_fn	*get_tag_fn;

	unsigned short		flags;
	unsigned short		tuple_size;
	unsigned short		sector_size;
	unsigned short		tag_size;

	const char		*name;

	struct kobject		kobj;
};

extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
extern void blk_integrity_unregister(struct gendisk *);
1250
extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
1251 1252 1253
extern int blk_rq_map_integrity_sg(struct request *, struct scatterlist *);
extern int blk_rq_count_integrity_sg(struct request *);

1254 1255 1256 1257 1258 1259
static inline
struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
{
	return bdev->bd_disk->integrity;
}

1260 1261 1262 1263 1264
static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
{
	return disk->integrity;
}

1265 1266
static inline int blk_integrity_rq(struct request *rq)
{
1267 1268 1269
	if (rq->bio == NULL)
		return 0;

1270 1271 1272 1273 1274 1275 1276 1277
	return bio_integrity(rq->bio);
}

#else /* CONFIG_BLK_DEV_INTEGRITY */

#define blk_integrity_rq(rq)			(0)
#define blk_rq_count_integrity_sg(a)		(0)
#define blk_rq_map_integrity_sg(a, b)		(0)
1278
#define bdev_get_integrity(a)			(0)
1279
#define blk_get_integrity(a)			(0)
1280 1281 1282 1283 1284 1285
#define blk_integrity_compare(a, b)		(0)
#define blk_integrity_register(a, b)		(0)
#define blk_integrity_unregister(a)		do { } while (0);

#endif /* CONFIG_BLK_DEV_INTEGRITY */

1286
struct block_device_operations {
A
Al Viro 已提交
1287 1288 1289 1290 1291
	int (*open) (struct block_device *, fmode_t);
	int (*release) (struct gendisk *, fmode_t);
	int (*locked_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
	int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
	int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1292 1293 1294
	int (*direct_access) (struct block_device *, sector_t,
						void **, unsigned long *);
	int (*media_changed) (struct gendisk *);
1295 1296
	unsigned long long (*set_capacity) (struct gendisk *,
						unsigned long long);
1297 1298 1299 1300 1301
	int (*revalidate_disk) (struct gendisk *);
	int (*getgeo)(struct block_device *, struct hd_geometry *);
	struct module *owner;
};

1302 1303
extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
				 unsigned long);
1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316
#else /* CONFIG_BLOCK */
/*
 * stubs for when the block layer is configured out
 */
#define buffer_heads_over_limit 0

static inline long nr_blockdev_pages(void)
{
	return 0;
}

#endif /* CONFIG_BLOCK */

L
Linus Torvalds 已提交
1317
#endif