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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_BLKDEV_H
2#define _LINUX_BLKDEV_H
3
Russell King85fd0bc2012-05-14 08:29:23 +02004#include <linux/sched.h>
5
Jens Axboef5ff8422007-09-21 09:19:54 +02006#ifdef CONFIG_BLOCK
7
Linus Torvalds1da177e2005-04-16 15:20:36 -07008#include <linux/major.h>
9#include <linux/genhd.h>
10#include <linux/list.h>
Jens Axboe320ae512013-10-24 09:20:05 +010011#include <linux/llist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/timer.h>
13#include <linux/workqueue.h>
14#include <linux/pagemap.h>
Tejun Heo66114ca2015-05-22 17:13:32 -040015#include <linux/backing-dev-defs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070016#include <linux/wait.h>
17#include <linux/mempool.h>
Dan Williams34c0fd52016-01-15 16:56:14 -080018#include <linux/pfn.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/bio.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070020#include <linux/stringify.h>
Hugh Dickins3e6053d2008-09-11 10:57:55 +020021#include <linux/gfp.h>
FUJITA Tomonorid351af02007-07-09 12:40:35 +020022#include <linux/bsg.h>
Jens Axboec7c22e42008-09-13 20:26:01 +020023#include <linux/smp.h>
Tejun Heo548bc8e2013-01-09 08:05:13 -080024#include <linux/rcupdate.h>
Tejun Heoadd703f2014-07-01 10:34:38 -060025#include <linux/percpu-refcount.h>
Christoph Hellwig84be4562015-05-01 12:46:15 +020026#include <linux/scatterlist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070027
Paul Gortmakerde477252011-05-26 13:46:22 -040028struct module;
Christoph Hellwig21b2f0c2006-03-22 17:52:04 +010029struct scsi_ioctl_command;
30
Linus Torvalds1da177e2005-04-16 15:20:36 -070031struct request_queue;
Linus Torvalds1da177e2005-04-16 15:20:36 -070032struct elevator_queue;
Jens Axboe2056a782006-03-23 20:00:26 +010033struct blk_trace;
Jens Axboe3d6392c2007-07-09 12:38:05 +020034struct request;
35struct sg_io_hdr;
Mike Christieaa387cc2011-07-31 22:05:09 +020036struct bsg_job;
Tejun Heo3c798392012-04-16 13:57:25 -070037struct blkcg_gq;
Ming Lei7c94e1c2014-09-25 23:23:43 +080038struct blk_flush_queue;
Christoph Hellwigbbd3e062015-10-15 14:10:48 +020039struct pr_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -070040
41#define BLKDEV_MIN_RQ 4
42#define BLKDEV_MAX_RQ 128 /* Default maximum */
43
Tejun Heo8bd435b2012-04-13 13:11:28 -070044/*
45 * Maximum number of blkcg policies allowed to be registered concurrently.
46 * Defined here to simplify include dependency.
47 */
48#define BLKCG_MAX_POLS 2
49
Linus Torvalds1da177e2005-04-16 15:20:36 -070050struct request;
Tejun Heo8ffdc652006-01-06 09:49:03 +010051typedef void (rq_end_io_fn)(struct request *, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
Tejun Heo5b788ce2012-06-04 20:40:59 -070053#define BLK_RL_SYNCFULL (1U << 0)
54#define BLK_RL_ASYNCFULL (1U << 1)
55
Linus Torvalds1da177e2005-04-16 15:20:36 -070056struct request_list {
Tejun Heo5b788ce2012-06-04 20:40:59 -070057 struct request_queue *q; /* the queue this rl belongs to */
Tejun Heoa0516612012-06-26 15:05:44 -070058#ifdef CONFIG_BLK_CGROUP
59 struct blkcg_gq *blkg; /* blkg this request pool belongs to */
60#endif
Jens Axboe1faa16d2009-04-06 14:48:01 +020061 /*
62 * count[], starved[], and wait[] are indexed by
63 * BLK_RW_SYNC/BLK_RW_ASYNC
64 */
Tejun Heo8a5ecdd2012-06-04 20:40:58 -070065 int count[2];
66 int starved[2];
67 mempool_t *rq_pool;
68 wait_queue_head_t wait[2];
Tejun Heo5b788ce2012-06-04 20:40:59 -070069 unsigned int flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -070070};
71
Jens Axboe4aff5e22006-08-10 08:44:47 +020072/*
73 * request command types
74 */
75enum rq_cmd_type_bits {
76 REQ_TYPE_FS = 1, /* fs request */
77 REQ_TYPE_BLOCK_PC, /* scsi command */
Christoph Hellwigb42171e2015-04-17 22:37:17 +020078 REQ_TYPE_DRV_PRIV, /* driver defined types from here */
Jens Axboe4aff5e22006-08-10 08:44:47 +020079};
80
Linus Torvalds1da177e2005-04-16 15:20:36 -070081#define BLK_MAX_CDB 16
82
83/*
Christoph Hellwigaf76e552014-05-06 12:12:45 +020084 * Try to put the fields that are referenced together in the same cacheline.
85 *
86 * If you modify this structure, make sure to update blk_rq_init() and
87 * especially blk_mq_rq_ctx_init() to take care of the added fields.
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 */
89struct request {
Christoph Hellwig6897fc22014-01-30 15:45:47 -080090 struct list_head queuelist;
Jens Axboe320ae512013-10-24 09:20:05 +010091 union {
92 struct call_single_data csd;
Jan Kara8b4922d2014-02-24 16:39:52 +010093 unsigned long fifo_time;
Jens Axboe320ae512013-10-24 09:20:05 +010094 };
Jens Axboeff856ba2006-01-09 16:02:34 +010095
Jens Axboe165125e2007-07-24 09:28:11 +020096 struct request_queue *q;
Jens Axboe320ae512013-10-24 09:20:05 +010097 struct blk_mq_ctx *mq_ctx;
Jens Axboee6a1c872006-08-10 09:00:21 +020098
Jens Axboe59533162013-05-23 12:25:08 +020099 u64 cmd_flags;
Christoph Hellwigb42171e2015-04-17 22:37:17 +0200100 unsigned cmd_type;
Jens Axboe242f9dc2008-09-14 05:55:09 -0700101 unsigned long atomic_flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102
Richard Kennedy181fdde2010-03-19 08:58:16 +0100103 int cpu;
104
Tejun Heoa2dec7b2009-05-07 22:24:44 +0900105 /* the following two fields are internal, NEVER access directly */
Tejun Heoa2dec7b2009-05-07 22:24:44 +0900106 unsigned int __data_len; /* total data len */
Richard Kennedy181fdde2010-03-19 08:58:16 +0100107 sector_t __sector; /* sector cursor */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108
109 struct bio *bio;
110 struct bio *biotail;
111
Jens Axboe360f92c2014-04-09 20:27:01 -0600112 /*
113 * The hash is used inside the scheduler, and killed once the
114 * request reaches the dispatch list. The ipi_list is only used
115 * to queue the request for softirq completion, which is long
116 * after the request has been unhashed (and even removed from
117 * the dispatch list).
118 */
119 union {
120 struct hlist_node hash; /* merge hash */
121 struct list_head ipi_list;
122 };
123
Jens Axboee6a1c872006-08-10 09:00:21 +0200124 /*
125 * The rb_node is only used inside the io scheduler, requests
126 * are pruned when moved to the dispatch queue. So let the
Mike Snitzerc1867942011-02-11 11:08:00 +0100127 * completion_data share space with the rb_node.
Jens Axboee6a1c872006-08-10 09:00:21 +0200128 */
129 union {
130 struct rb_node rb_node; /* sort/lookup */
Mike Snitzerc1867942011-02-11 11:08:00 +0100131 void *completion_data;
Jens Axboee6a1c872006-08-10 09:00:21 +0200132 };
Jens Axboe98170642006-07-28 09:23:08 +0200133
Jens Axboeff7d1452006-07-12 14:04:37 +0200134 /*
Vivek Goyal7f1dc8a2010-04-21 17:44:16 +0200135 * Three pointers are available for the IO schedulers, if they need
Mike Snitzerc1867942011-02-11 11:08:00 +0100136 * more they have to dynamically allocate it. Flush requests are
137 * never put on the IO scheduler. So let the flush fields share
Tejun Heoa612fdd2011-12-14 00:33:41 +0100138 * space with the elevator data.
Jens Axboeff7d1452006-07-12 14:04:37 +0200139 */
Mike Snitzerc1867942011-02-11 11:08:00 +0100140 union {
Tejun Heoa612fdd2011-12-14 00:33:41 +0100141 struct {
142 struct io_cq *icq;
143 void *priv[2];
144 } elv;
145
Mike Snitzerc1867942011-02-11 11:08:00 +0100146 struct {
147 unsigned int seq;
148 struct list_head list;
Jeff Moyer4853aba2011-08-15 21:37:25 +0200149 rq_end_io_fn *saved_end_io;
Mike Snitzerc1867942011-02-11 11:08:00 +0100150 } flush;
151 };
Jens Axboeff7d1452006-07-12 14:04:37 +0200152
Jens Axboe8f34ee72006-06-13 09:02:34 +0200153 struct gendisk *rq_disk;
Jerome Marchand09e099d2011-01-05 16:57:38 +0100154 struct hd_struct *part;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155 unsigned long start_time;
Divyesh Shah91952912010-04-01 15:01:41 -0700156#ifdef CONFIG_BLK_CGROUP
Tejun Heoa0516612012-06-26 15:05:44 -0700157 struct request_list *rl; /* rl this rq is alloced from */
Divyesh Shah91952912010-04-01 15:01:41 -0700158 unsigned long long start_time_ns;
159 unsigned long long io_start_time_ns; /* when passed to hardware */
160#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 /* Number of scatter-gather DMA addr+len pairs after
162 * physical address coalescing is performed.
163 */
164 unsigned short nr_phys_segments;
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200165#if defined(CONFIG_BLK_DEV_INTEGRITY)
166 unsigned short nr_integrity_segments;
167#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168
Jens Axboe8f34ee72006-06-13 09:02:34 +0200169 unsigned short ioprio;
170
Tejun Heo731ec492009-04-23 11:05:20 +0900171 void *special; /* opaque pointer available for LLD use */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172
Jens Axboecdd60262006-07-28 09:32:07 +0200173 int tag;
174 int errors;
175
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 /*
177 * when request is used as a packet command carrier
178 */
FUJITA Tomonorid7e3c322008-04-29 09:54:39 +0200179 unsigned char __cmd[BLK_MAX_CDB];
180 unsigned char *cmd;
Richard Kennedy181fdde2010-03-19 08:58:16 +0100181 unsigned short cmd_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100183 unsigned int extra_len; /* length of alignment and padding */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184 unsigned int sense_len;
Tejun Heoc3a4d782009-05-07 22:24:37 +0900185 unsigned int resid_len; /* residual count */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 void *sense;
187
Jens Axboe242f9dc2008-09-14 05:55:09 -0700188 unsigned long deadline;
189 struct list_head timeout_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190 unsigned int timeout;
Mike Christie17e01f22005-11-11 05:31:37 -0600191 int retries;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192
193 /*
Jens Axboec00895a2006-09-30 20:29:12 +0200194 * completion callback.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195 */
196 rq_end_io_fn *end_io;
197 void *end_io_data;
FUJITA Tomonoriabae1fd2007-07-16 08:52:14 +0200198
199 /* for bidi */
200 struct request *next_rq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201};
202
Fernando Luis Vázquez Cao766ca442008-08-14 09:59:13 +0200203static inline unsigned short req_get_ioprio(struct request *req)
204{
205 return req->ioprio;
206}
207
Linus Torvalds1da177e2005-04-16 15:20:36 -0700208#include <linux/elevator.h>
209
Jens Axboe320ae512013-10-24 09:20:05 +0100210struct blk_queue_ctx;
211
Jens Axboe165125e2007-07-24 09:28:11 +0200212typedef void (request_fn_proc) (struct request_queue *q);
Jens Axboedece1632015-11-05 10:41:16 -0700213typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio);
Jens Axboe165125e2007-07-24 09:28:11 +0200214typedef int (prep_rq_fn) (struct request_queue *, struct request *);
James Bottomley28018c22010-07-01 19:49:17 +0900215typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216
217struct bio_vec;
Jens Axboeff856ba2006-01-09 16:02:34 +0100218typedef void (softirq_done_fn)(struct request *);
Tejun Heo2fb98e82008-02-19 11:36:53 +0100219typedef int (dma_drain_needed_fn)(struct request *);
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +0200220typedef int (lld_busy_fn) (struct request_queue *q);
Mike Christieaa387cc2011-07-31 22:05:09 +0200221typedef int (bsg_job_fn) (struct bsg_job *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222
Jens Axboe242f9dc2008-09-14 05:55:09 -0700223enum blk_eh_timer_return {
224 BLK_EH_NOT_HANDLED,
225 BLK_EH_HANDLED,
226 BLK_EH_RESET_TIMER,
227};
228
229typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
230
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231enum blk_queue_state {
232 Queue_down,
233 Queue_up,
234};
235
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236struct blk_queue_tag {
237 struct request **tag_index; /* map of busy tags */
238 unsigned long *tag_map; /* bit map of free/busy tags */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 int busy; /* current depth */
240 int max_depth; /* what we will send to device */
Tejun Heoba025082005-08-05 13:28:11 -0700241 int real_max_depth; /* what the array can hold */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242 atomic_t refcnt; /* map can be shared */
Shaohua Liee1b6f72015-01-15 17:32:25 -0800243 int alloc_policy; /* tag allocation policy */
244 int next_tag; /* next tag */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245};
Shaohua Liee1b6f72015-01-15 17:32:25 -0800246#define BLK_TAG_ALLOC_FIFO 0 /* allocate starting from 0 */
247#define BLK_TAG_ALLOC_RR 1 /* allocate starting from last allocated tag */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900249#define BLK_SCSI_MAX_CMDS (256)
250#define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
251
Martin K. Petersen025146e2009-05-22 17:17:51 -0400252struct queue_limits {
253 unsigned long bounce_pfn;
254 unsigned long seg_boundary_mask;
Keith Busch03100aa2015-08-19 14:24:05 -0700255 unsigned long virt_boundary_mask;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400256
257 unsigned int max_hw_sectors;
Martin K. Petersenca369d52015-11-13 16:46:48 -0500258 unsigned int max_dev_sectors;
Jens Axboe762380a2014-06-05 13:38:39 -0600259 unsigned int chunk_sectors;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400260 unsigned int max_sectors;
261 unsigned int max_segment_size;
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400262 unsigned int physical_block_size;
263 unsigned int alignment_offset;
264 unsigned int io_min;
265 unsigned int io_opt;
Christoph Hellwig67efc922009-09-30 13:54:20 +0200266 unsigned int max_discard_sectors;
Jens Axboe0034af02015-07-16 09:14:26 -0600267 unsigned int max_hw_discard_sectors;
Martin K. Petersen4363ac72012-09-18 12:19:27 -0400268 unsigned int max_write_same_sectors;
Martin K. Petersen86b37282009-11-10 11:50:21 +0100269 unsigned int discard_granularity;
270 unsigned int discard_alignment;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400271
272 unsigned short logical_block_size;
Martin K. Petersen8a783622010-02-26 00:20:39 -0500273 unsigned short max_segments;
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200274 unsigned short max_integrity_segments;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400275
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400276 unsigned char misaligned;
Martin K. Petersen86b37282009-11-10 11:50:21 +0100277 unsigned char discard_misaligned;
Martin K. Petersene692cb62010-12-01 19:41:49 +0100278 unsigned char cluster;
Martin K. Petersena934a002011-05-18 10:37:35 +0200279 unsigned char discard_zeroes_data;
Kent Overstreetc78afc62013-07-11 22:39:53 -0700280 unsigned char raid_partial_stripes_expensive;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400281};
282
Richard Kennedyd7b76302011-07-13 21:17:23 +0200283struct request_queue {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284 /*
285 * Together with queue_head for cacheline sharing
286 */
287 struct list_head queue_head;
288 struct request *last_merge;
Jens Axboeb374d182008-10-31 10:05:07 +0100289 struct elevator_queue *elevator;
Tejun Heo8a5ecdd2012-06-04 20:40:58 -0700290 int nr_rqs[2]; /* # allocated [a]sync rqs */
291 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292
293 /*
Tejun Heoa0516612012-06-26 15:05:44 -0700294 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
295 * is used, root blkg allocates from @q->root_rl and all other
296 * blkgs from their own blkg->rl. Which one to use should be
297 * determined using bio_request_list().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298 */
Tejun Heoa0516612012-06-26 15:05:44 -0700299 struct request_list root_rl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300
301 request_fn_proc *request_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302 make_request_fn *make_request_fn;
303 prep_rq_fn *prep_rq_fn;
James Bottomley28018c22010-07-01 19:49:17 +0900304 unprep_rq_fn *unprep_rq_fn;
Jens Axboeff856ba2006-01-09 16:02:34 +0100305 softirq_done_fn *softirq_done_fn;
Jens Axboe242f9dc2008-09-14 05:55:09 -0700306 rq_timed_out_fn *rq_timed_out_fn;
Tejun Heo2fb98e82008-02-19 11:36:53 +0100307 dma_drain_needed_fn *dma_drain_needed;
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +0200308 lld_busy_fn *lld_busy_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309
Jens Axboe320ae512013-10-24 09:20:05 +0100310 struct blk_mq_ops *mq_ops;
311
312 unsigned int *mq_map;
313
314 /* sw queues */
Ming Leie6cdb092014-06-03 11:24:06 +0800315 struct blk_mq_ctx __percpu *queue_ctx;
Jens Axboe320ae512013-10-24 09:20:05 +0100316 unsigned int nr_queues;
317
318 /* hw dispatch queues */
319 struct blk_mq_hw_ctx **queue_hw_ctx;
320 unsigned int nr_hw_queues;
321
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 /*
Tejun Heo8922e162005-10-20 16:23:44 +0200323 * Dispatch queue sorting
324 */
Jens Axboe1b47f532005-10-20 16:37:00 +0200325 sector_t end_sector;
Tejun Heo8922e162005-10-20 16:23:44 +0200326 struct request *boundary_rq;
Tejun Heo8922e162005-10-20 16:23:44 +0200327
328 /*
Jens Axboe3cca6dc2011-03-02 11:08:00 -0500329 * Delayed queue handling
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330 */
Jens Axboe3cca6dc2011-03-02 11:08:00 -0500331 struct delayed_work delay_work;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332
333 struct backing_dev_info backing_dev_info;
334
335 /*
336 * The queue owner gets to use this for whatever they like.
337 * ll_rw_blk doesn't touch it.
338 */
339 void *queuedata;
340
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342 * various queue flags, see QUEUE_* below
343 */
344 unsigned long queue_flags;
345
346 /*
Tejun Heoa73f7302011-12-14 00:33:37 +0100347 * ida allocated id for this queue. Used to index queues from
348 * ioctx.
349 */
350 int id;
351
352 /*
Richard Kennedyd7b76302011-07-13 21:17:23 +0200353 * queue needs bounce pages for pages above this limit
354 */
355 gfp_t bounce_gfp;
356
357 /*
152587d2005-04-12 16:22:06 -0500358 * protects queue structures from reentrancy. ->__queue_lock should
359 * _never_ be used directly, it is queue private. always use
360 * ->queue_lock.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361 */
152587d2005-04-12 16:22:06 -0500362 spinlock_t __queue_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363 spinlock_t *queue_lock;
364
365 /*
366 * queue kobject
367 */
368 struct kobject kobj;
369
Jens Axboe320ae512013-10-24 09:20:05 +0100370 /*
371 * mq queue kobject
372 */
373 struct kobject mq_kobj;
374
Dan Williamsac6fc482015-10-21 13:20:18 -0400375#ifdef CONFIG_BLK_DEV_INTEGRITY
376 struct blk_integrity integrity;
377#endif /* CONFIG_BLK_DEV_INTEGRITY */
378
Rafael J. Wysocki47fafbc2014-12-04 01:00:23 +0100379#ifdef CONFIG_PM
Lin Ming6c954662013-03-23 11:42:26 +0800380 struct device *dev;
381 int rpm_status;
382 unsigned int nr_pending;
383#endif
384
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385 /*
386 * queue settings
387 */
388 unsigned long nr_requests; /* Max # of requests */
389 unsigned int nr_congestion_on;
390 unsigned int nr_congestion_off;
391 unsigned int nr_batching;
392
James Bottomleyfa0ccd82008-01-10 11:30:36 -0600393 unsigned int dma_drain_size;
Richard Kennedyd7b76302011-07-13 21:17:23 +0200394 void *dma_drain_buffer;
Tejun Heoe3790c72008-03-04 11:18:17 +0100395 unsigned int dma_pad_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700396 unsigned int dma_alignment;
397
398 struct blk_queue_tag *queue_tags;
Jens Axboe6eca9002007-10-25 10:14:47 +0200399 struct list_head tag_busy_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400
Tejun Heo15853af2005-11-10 08:52:05 +0100401 unsigned int nr_sorted;
Jens Axboe0a7ae2f2009-05-20 08:54:31 +0200402 unsigned int in_flight[2];
Bart Van Assche24faf6f2012-11-28 13:46:45 +0100403 /*
404 * Number of active block driver functions for which blk_drain_queue()
405 * must wait. Must be incremented around functions that unlock the
406 * queue_lock internally, e.g. scsi_request_fn().
407 */
408 unsigned int request_fn_active;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409
Jens Axboe242f9dc2008-09-14 05:55:09 -0700410 unsigned int rq_timeout;
411 struct timer_list timeout;
Christoph Hellwig287922e2015-10-30 20:57:30 +0800412 struct work_struct timeout_work;
Jens Axboe242f9dc2008-09-14 05:55:09 -0700413 struct list_head timeout_list;
414
Tejun Heoa612fdd2011-12-14 00:33:41 +0100415 struct list_head icq_list;
Tejun Heo4eef3042012-03-05 13:15:18 -0800416#ifdef CONFIG_BLK_CGROUP
Tejun Heoa2b16932012-04-13 13:11:33 -0700417 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
Tejun Heo3c798392012-04-16 13:57:25 -0700418 struct blkcg_gq *root_blkg;
Tejun Heo03aa2642012-03-05 13:15:19 -0800419 struct list_head blkg_list;
Tejun Heo4eef3042012-03-05 13:15:18 -0800420#endif
Tejun Heoa612fdd2011-12-14 00:33:41 +0100421
Martin K. Petersen025146e2009-05-22 17:17:51 -0400422 struct queue_limits limits;
423
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 /*
425 * sg stuff
426 */
427 unsigned int sg_timeout;
428 unsigned int sg_reserved_size;
Christoph Lameter19460892005-06-23 00:08:19 -0700429 int node;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700430#ifdef CONFIG_BLK_DEV_IO_TRACE
Jens Axboe2056a782006-03-23 20:00:26 +0100431 struct blk_trace *blk_trace;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700432#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433 /*
Tejun Heo4913efe2010-09-03 11:56:16 +0200434 * for flush operations
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435 */
Tejun Heo4913efe2010-09-03 11:56:16 +0200436 unsigned int flush_flags;
shaohua.li@intel.comf3876932011-05-06 11:34:32 -0600437 unsigned int flush_not_queueable:1;
Ming Lei7c94e1c2014-09-25 23:23:43 +0800438 struct blk_flush_queue *fq;
Al Viro483f4af2006-03-18 18:34:37 -0500439
Christoph Hellwig6fca6a62014-05-28 08:08:02 -0600440 struct list_head requeue_list;
441 spinlock_t requeue_lock;
442 struct work_struct requeue_work;
443
Al Viro483f4af2006-03-18 18:34:37 -0500444 struct mutex sysfs_lock;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200445
Tejun Heod7325802012-03-05 13:14:58 -0800446 int bypass_depth;
Christoph Hellwig4ecd4fe2015-05-07 09:38:13 +0200447 atomic_t mq_freeze_depth;
Tejun Heod7325802012-03-05 13:14:58 -0800448
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200449#if defined(CONFIG_BLK_DEV_BSG)
Mike Christieaa387cc2011-07-31 22:05:09 +0200450 bsg_job_fn *bsg_job_fn;
451 int bsg_job_size;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200452 struct bsg_class_device bsg_dev;
453#endif
Vivek Goyale43473b2010-09-15 17:06:35 -0400454
455#ifdef CONFIG_BLK_DEV_THROTTLING
456 /* Throttle data */
457 struct throtl_data *td;
458#endif
Tejun Heo548bc8e2013-01-09 08:05:13 -0800459 struct rcu_head rcu_head;
Jens Axboe320ae512013-10-24 09:20:05 +0100460 wait_queue_head_t mq_freeze_wq;
Dan Williams3ef28e82015-10-21 13:20:12 -0400461 struct percpu_ref q_usage_counter;
Jens Axboe320ae512013-10-24 09:20:05 +0100462 struct list_head all_q_node;
Jens Axboe0d2602c2014-05-13 15:10:52 -0600463
464 struct blk_mq_tag_set *tag_set;
465 struct list_head tag_set_list;
Kent Overstreet54efd502015-04-23 22:37:18 -0700466 struct bio_set *bio_split;
Akinobu Mita4593fdb2015-09-27 02:09:20 +0900467
468 bool mq_sysfs_init_done;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469};
470
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471#define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
472#define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
Jens Axboe1faa16d2009-04-06 14:48:01 +0200473#define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
474#define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
Bart Van Assche3f3299d2012-11-28 13:42:38 +0100475#define QUEUE_FLAG_DYING 5 /* queue being torn down */
Tejun Heod7325802012-03-05 13:14:58 -0800476#define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
Jens Axboec21e6be2011-04-19 13:32:46 +0200477#define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
478#define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
Dan Williams5757a6d2011-07-23 20:44:25 +0200479#define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
Jens Axboec21e6be2011-04-19 13:32:46 +0200480#define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
481#define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
482#define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
Fernando Luis Vázquez Cao88e740f2008-10-27 18:44:46 +0900483#define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
Jens Axboec21e6be2011-04-19 13:32:46 +0200484#define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
485#define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
486#define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
487#define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
488#define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
Dan Williams5757a6d2011-07-23 20:44:25 +0200489#define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
Bart Van Asschec246e802012-12-06 14:32:01 +0100490#define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
Jens Axboe320ae512013-10-24 09:20:05 +0100491#define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
Jens Axboe05f1dd52014-05-29 09:53:32 -0600492#define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
Jens Axboe05229be2015-11-05 10:44:55 -0700493#define QUEUE_FLAG_POLL 22 /* IO polling enabled if set */
Jens Axboebc58ba92009-01-23 10:54:44 +0100494
495#define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
Jens Axboe01e97f62009-09-03 20:06:47 +0200496 (1 << QUEUE_FLAG_STACKABLE) | \
Jens Axboee2e1a142010-06-09 10:42:09 +0200497 (1 << QUEUE_FLAG_SAME_COMP) | \
498 (1 << QUEUE_FLAG_ADD_RANDOM))
Tejun Heo797e7db2006-01-06 09:51:03 +0100499
Jens Axboe94eddfb2013-11-19 09:25:07 -0700500#define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
Mike Snitzerad9cf3b2014-12-16 12:54:25 -0500501 (1 << QUEUE_FLAG_STACKABLE) | \
Jens Axboe94eddfb2013-11-19 09:25:07 -0700502 (1 << QUEUE_FLAG_SAME_COMP))
503
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200504static inline void queue_lockdep_assert_held(struct request_queue *q)
Linus Torvalds8f45c1a2008-04-29 10:16:38 -0700505{
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200506 if (q->queue_lock)
507 lockdep_assert_held(q->queue_lock);
Linus Torvalds8f45c1a2008-04-29 10:16:38 -0700508}
509
Nick Piggin75ad23b2008-04-29 14:48:33 +0200510static inline void queue_flag_set_unlocked(unsigned int flag,
511 struct request_queue *q)
512{
513 __set_bit(flag, &q->queue_flags);
514}
515
Jens Axboee48ec692008-07-03 13:18:54 +0200516static inline int queue_flag_test_and_clear(unsigned int flag,
517 struct request_queue *q)
518{
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200519 queue_lockdep_assert_held(q);
Jens Axboee48ec692008-07-03 13:18:54 +0200520
521 if (test_bit(flag, &q->queue_flags)) {
522 __clear_bit(flag, &q->queue_flags);
523 return 1;
524 }
525
526 return 0;
527}
528
529static inline int queue_flag_test_and_set(unsigned int flag,
530 struct request_queue *q)
531{
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200532 queue_lockdep_assert_held(q);
Jens Axboee48ec692008-07-03 13:18:54 +0200533
534 if (!test_bit(flag, &q->queue_flags)) {
535 __set_bit(flag, &q->queue_flags);
536 return 0;
537 }
538
539 return 1;
540}
541
Nick Piggin75ad23b2008-04-29 14:48:33 +0200542static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
543{
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200544 queue_lockdep_assert_held(q);
Nick Piggin75ad23b2008-04-29 14:48:33 +0200545 __set_bit(flag, &q->queue_flags);
546}
547
548static inline void queue_flag_clear_unlocked(unsigned int flag,
549 struct request_queue *q)
550{
551 __clear_bit(flag, &q->queue_flags);
552}
553
Jens Axboe0a7ae2f2009-05-20 08:54:31 +0200554static inline int queue_in_flight(struct request_queue *q)
555{
556 return q->in_flight[0] + q->in_flight[1];
557}
558
Nick Piggin75ad23b2008-04-29 14:48:33 +0200559static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
560{
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200561 queue_lockdep_assert_held(q);
Nick Piggin75ad23b2008-04-29 14:48:33 +0200562 __clear_bit(flag, &q->queue_flags);
563}
564
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565#define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
566#define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
Bart Van Assche3f3299d2012-11-28 13:42:38 +0100567#define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
Bart Van Asschec246e802012-12-06 14:32:01 +0100568#define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
Tejun Heod7325802012-03-05 13:14:58 -0800569#define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
Jens Axboe320ae512013-10-24 09:20:05 +0100570#define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
Alan D. Brunelleac9fafa2008-04-29 14:44:19 +0200571#define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
Alan D. Brunelle488991e2010-01-29 09:04:08 +0100572#define blk_queue_noxmerges(q) \
573 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
Jens Axboea68bbdd2008-09-24 13:03:33 +0200574#define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
Jens Axboebc58ba92009-01-23 10:54:44 +0100575#define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
Jens Axboee2e1a142010-06-09 10:42:09 +0200576#define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
Kiyoshi Ueda4ee5eaf2008-09-18 10:46:13 -0400577#define blk_queue_stackable(q) \
578 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
Christoph Hellwigc15227d2009-09-30 13:52:12 +0200579#define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
Adrian Hunter8d57a982010-08-11 14:17:49 -0700580#define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
581 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582
Christoph Hellwig33659eb2010-08-07 18:17:56 +0200583#define blk_noretry_request(rq) \
584 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
585 REQ_FAILFAST_DRIVER))
Jens Axboe4aff5e22006-08-10 08:44:47 +0200586
Christoph Hellwig33659eb2010-08-07 18:17:56 +0200587#define blk_account_rq(rq) \
588 (((rq)->cmd_flags & REQ_STARTED) && \
Martin K. Petersene2a60da2012-09-18 12:19:25 -0400589 ((rq)->cmd_type == REQ_TYPE_FS))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590
Jens Axboeab780f12008-08-26 10:25:02 +0200591#define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
FUJITA Tomonoriabae1fd2007-07-16 08:52:14 +0200592#define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
Kiyoshi Ueda336cdb42007-12-11 17:40:30 -0500593/* rq->queuelist of dequeued request must be list_empty() */
594#define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595
596#define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
597
Linus Torvalds10fbd362015-05-27 15:32:15 -0700598#define rq_data_dir(rq) ((int)((rq)->cmd_flags & 1))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599
Jens Axboe49fd5242014-04-16 10:57:18 -0600600/*
601 * Driver can handle struct request, if it either has an old style
602 * request_fn defined, or is blk-mq based.
603 */
604static inline bool queue_is_rq_based(struct request_queue *q)
605{
606 return q->request_fn || q->mq_ops;
607}
608
Martin K. Petersene692cb62010-12-01 19:41:49 +0100609static inline unsigned int blk_queue_cluster(struct request_queue *q)
610{
611 return q->limits.cluster;
612}
613
Jens Axboe9e2585a2006-07-28 09:26:13 +0200614/*
Jens Axboe1faa16d2009-04-06 14:48:01 +0200615 * We regard a request as sync, if either a read or a sync write
Jens Axboe9e2585a2006-07-28 09:26:13 +0200616 */
Jens Axboe1faa16d2009-04-06 14:48:01 +0200617static inline bool rw_is_sync(unsigned int rw_flags)
618{
Christoph Hellwig7b6d91d2010-08-07 18:20:39 +0200619 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
Jens Axboe1faa16d2009-04-06 14:48:01 +0200620}
621
622static inline bool rq_is_sync(struct request *rq)
623{
624 return rw_is_sync(rq->cmd_flags);
625}
626
Tejun Heo5b788ce2012-06-04 20:40:59 -0700627static inline bool blk_rl_full(struct request_list *rl, bool sync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628{
Tejun Heo5b788ce2012-06-04 20:40:59 -0700629 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
630
631 return rl->flags & flag;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700632}
633
Tejun Heo5b788ce2012-06-04 20:40:59 -0700634static inline void blk_set_rl_full(struct request_list *rl, bool sync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635{
Tejun Heo5b788ce2012-06-04 20:40:59 -0700636 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
637
638 rl->flags |= flag;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639}
640
Tejun Heo5b788ce2012-06-04 20:40:59 -0700641static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642{
Tejun Heo5b788ce2012-06-04 20:40:59 -0700643 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
644
645 rl->flags &= ~flag;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646}
647
Martin K. Petersene2a60da2012-09-18 12:19:25 -0400648static inline bool rq_mergeable(struct request *rq)
649{
650 if (rq->cmd_type != REQ_TYPE_FS)
651 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652
Martin K. Petersene2a60da2012-09-18 12:19:25 -0400653 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
654 return false;
655
656 return true;
657}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400659static inline bool blk_check_merge_flags(unsigned int flags1,
660 unsigned int flags2)
661{
662 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
663 return false;
664
665 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
666 return false;
667
Martin K. Petersen4363ac72012-09-18 12:19:27 -0400668 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
669 return false;
670
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400671 return true;
672}
673
Martin K. Petersen4363ac72012-09-18 12:19:27 -0400674static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
675{
676 if (bio_data(a) == bio_data(b))
677 return true;
678
679 return false;
680}
681
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683 * q->prep_rq_fn return values
684 */
685#define BLKPREP_OK 0 /* serve it */
686#define BLKPREP_KILL 1 /* fatal error, kill */
687#define BLKPREP_DEFER 2 /* leave on queue */
688
689extern unsigned long blk_max_low_pfn, blk_max_pfn;
690
691/*
692 * standard bounce addresses:
693 *
694 * BLK_BOUNCE_HIGH : bounce all highmem pages
695 * BLK_BOUNCE_ANY : don't bounce anything
696 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
697 */
Andi Kleen24728922008-04-21 09:51:05 +0200698
699#if BITS_PER_LONG == 32
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700#define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
Andi Kleen24728922008-04-21 09:51:05 +0200701#else
702#define BLK_BOUNCE_HIGH -1ULL
703#endif
704#define BLK_BOUNCE_ANY (-1ULL)
FUJITA Tomonoribfe17232010-05-31 15:59:03 +0900705#define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706
Jens Axboe3d6392c2007-07-09 12:38:05 +0200707/*
708 * default timeout for SG_IO if none specified
709 */
710#define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
Linus Torvaldsf2f1fa72008-12-05 14:49:18 -0800711#define BLK_MIN_SG_TIMEOUT (7 * HZ)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200712
Christoph Lameter2a7326b2007-07-17 04:03:37 -0700713#ifdef CONFIG_BOUNCE
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714extern int init_emergency_isa_pool(void);
Jens Axboe165125e2007-07-24 09:28:11 +0200715extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716#else
717static inline int init_emergency_isa_pool(void)
718{
719 return 0;
720}
Jens Axboe165125e2007-07-24 09:28:11 +0200721static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722{
723}
724#endif /* CONFIG_MMU */
725
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900726struct rq_map_data {
727 struct page **pages;
728 int page_order;
729 int nr_entries;
FUJITA Tomonori56c451f2008-12-18 14:49:37 +0900730 unsigned long offset;
FUJITA Tomonori97ae77a2008-12-18 14:49:38 +0900731 int null_mapped;
FUJITA Tomonoriecb554a2009-07-09 14:46:53 +0200732 int from_user;
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900733};
734
NeilBrown5705f702007-09-25 12:35:59 +0200735struct req_iterator {
Kent Overstreet79886132013-11-23 17:19:00 -0800736 struct bvec_iter iter;
NeilBrown5705f702007-09-25 12:35:59 +0200737 struct bio *bio;
738};
739
740/* This should not be used directly - use rq_for_each_segment */
Jens Axboe1e428072009-02-23 09:03:10 +0100741#define for_each_bio(_bio) \
742 for (; _bio; _bio = _bio->bi_next)
NeilBrown5705f702007-09-25 12:35:59 +0200743#define __rq_for_each_bio(_bio, rq) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744 if ((rq->bio)) \
745 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
746
NeilBrown5705f702007-09-25 12:35:59 +0200747#define rq_for_each_segment(bvl, _rq, _iter) \
748 __rq_for_each_bio(_iter.bio, _rq) \
Kent Overstreet79886132013-11-23 17:19:00 -0800749 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
NeilBrown5705f702007-09-25 12:35:59 +0200750
Kent Overstreet4550dd62013-08-07 14:26:21 -0700751#define rq_iter_last(bvec, _iter) \
Kent Overstreet79886132013-11-23 17:19:00 -0800752 (_iter.bio->bi_next == NULL && \
Kent Overstreet4550dd62013-08-07 14:26:21 -0700753 bio_iter_last(bvec, _iter.iter))
NeilBrown5705f702007-09-25 12:35:59 +0200754
Ilya Loginov2d4dc892009-11-26 09:16:19 +0100755#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
756# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
757#endif
758#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
759extern void rq_flush_dcache_pages(struct request *rq);
760#else
761static inline void rq_flush_dcache_pages(struct request *rq)
762{
763}
764#endif
765
Linus Torvalds1da177e2005-04-16 15:20:36 -0700766extern int blk_register_queue(struct gendisk *disk);
767extern void blk_unregister_queue(struct gendisk *disk);
Jens Axboedece1632015-11-05 10:41:16 -0700768extern blk_qc_t generic_make_request(struct bio *bio);
FUJITA Tomonori2a4aa302008-04-29 09:54:36 +0200769extern void blk_rq_init(struct request_queue *q, struct request *rq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770extern void blk_put_request(struct request *);
Jens Axboe165125e2007-07-24 09:28:11 +0200771extern void __blk_put_request(struct request_queue *, struct request *);
Jens Axboe165125e2007-07-24 09:28:11 +0200772extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
Boaz Harrosh79eb63e2009-05-17 18:57:15 +0300773extern struct request *blk_make_request(struct request_queue *, struct bio *,
774 gfp_t);
Jens Axboef27b0872014-06-06 07:57:37 -0600775extern void blk_rq_set_block_pc(struct request *);
Jens Axboe165125e2007-07-24 09:28:11 +0200776extern void blk_requeue_request(struct request_queue *, struct request *);
Christoph Hellwig66ac0282010-06-18 16:59:42 +0200777extern void blk_add_request_payload(struct request *rq, struct page *page,
778 unsigned int len);
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +0200779extern int blk_lld_busy(struct request_queue *q);
Mike Snitzer78d8e582015-06-26 10:01:13 -0400780extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
781 struct bio_set *bs, gfp_t gfp_mask,
782 int (*bio_ctr)(struct bio *, struct bio *, void *),
783 void *data);
784extern void blk_rq_unprep_clone(struct request *rq);
Kiyoshi Ueda82124d62008-09-18 10:45:38 -0400785extern int blk_insert_cloned_request(struct request_queue *q,
786 struct request *rq);
Jens Axboe3cca6dc2011-03-02 11:08:00 -0500787extern void blk_delay_queue(struct request_queue *, unsigned long);
Kent Overstreet54efd502015-04-23 22:37:18 -0700788extern void blk_queue_split(struct request_queue *, struct bio **,
789 struct bio_set *);
Jens Axboe165125e2007-07-24 09:28:11 +0200790extern void blk_recount_segments(struct request_queue *, struct bio *);
Paolo Bonzini0bfc96c2012-01-12 16:01:28 +0100791extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
Paolo Bonzini577ebb32012-01-12 16:01:27 +0100792extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
793 unsigned int, void __user *);
Al Viro74f3c8a2007-08-27 15:38:10 -0400794extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
795 unsigned int, void __user *);
Al Viroe915e872008-09-02 17:16:41 -0400796extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
797 struct scsi_ioctl_command __user *);
Andrew Morton3fcfab12006-10-19 23:28:16 -0700798
Christoph Hellwig6f3b0e82015-11-26 09:13:05 +0100799extern int blk_queue_enter(struct request_queue *q, bool nowait);
Dan Williams2e6edc92015-11-19 13:29:28 -0800800extern void blk_queue_exit(struct request_queue *q);
Jens Axboe165125e2007-07-24 09:28:11 +0200801extern void blk_start_queue(struct request_queue *q);
Jens Axboe21491412015-12-28 13:01:22 -0700802extern void blk_start_queue_async(struct request_queue *q);
Jens Axboe165125e2007-07-24 09:28:11 +0200803extern void blk_stop_queue(struct request_queue *q);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804extern void blk_sync_queue(struct request_queue *q);
Jens Axboe165125e2007-07-24 09:28:11 +0200805extern void __blk_stop_queue(struct request_queue *q);
Christoph Hellwig24ecfbe2011-04-18 11:41:33 +0200806extern void __blk_run_queue(struct request_queue *q);
Christoph Hellwiga7928c12015-04-17 22:37:20 +0200807extern void __blk_run_queue_uncond(struct request_queue *q);
Jens Axboe165125e2007-07-24 09:28:11 +0200808extern void blk_run_queue(struct request_queue *);
Jens Axboec21e6be2011-04-19 13:32:46 +0200809extern void blk_run_queue_async(struct request_queue *q);
FUJITA Tomonoria3bce902008-08-28 16:17:05 +0900810extern int blk_rq_map_user(struct request_queue *, struct request *,
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900811 struct rq_map_data *, void __user *, unsigned long,
812 gfp_t);
Jens Axboe8e5cfc42006-12-19 11:12:46 +0100813extern int blk_rq_unmap_user(struct bio *);
Jens Axboe165125e2007-07-24 09:28:11 +0200814extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
815extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
Kent Overstreet26e49cf2015-01-18 16:16:31 +0100816 struct rq_map_data *, const struct iov_iter *,
817 gfp_t);
Jens Axboe165125e2007-07-24 09:28:11 +0200818extern int blk_execute_rq(struct request_queue *, struct gendisk *,
James Bottomley 994ca9a2005-06-20 14:11:09 +0200819 struct request *, int);
Jens Axboe165125e2007-07-24 09:28:11 +0200820extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
Jens Axboe15fc8582006-01-06 10:00:50 +0100821 struct request *, int, rq_end_io_fn *);
Mike Christie6e39b69e2005-11-11 05:30:24 -0600822
Jens Axboe05229be2015-11-05 10:44:55 -0700823bool blk_poll(struct request_queue *q, blk_qc_t cookie);
824
Jens Axboe165125e2007-07-24 09:28:11 +0200825static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700826{
Tejun Heoff9ea322014-09-08 08:03:56 +0900827 return bdev->bd_disk->queue; /* this is never NULL */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828}
829
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830/*
Tejun Heo80a761f2009-07-03 17:48:17 +0900831 * blk_rq_pos() : the current sector
832 * blk_rq_bytes() : bytes left in the entire request
833 * blk_rq_cur_bytes() : bytes left in the current segment
834 * blk_rq_err_bytes() : bytes left till the next error boundary
835 * blk_rq_sectors() : sectors left in the entire request
836 * blk_rq_cur_sectors() : sectors left in the current segment
Tejun Heo5efccd12009-04-23 11:05:18 +0900837 */
Tejun Heo5b936292009-05-07 22:24:38 +0900838static inline sector_t blk_rq_pos(const struct request *rq)
839{
Tejun Heoa2dec7b2009-05-07 22:24:44 +0900840 return rq->__sector;
Tejun Heo5b936292009-05-07 22:24:38 +0900841}
842
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900843static inline unsigned int blk_rq_bytes(const struct request *rq)
844{
Tejun Heoa2dec7b2009-05-07 22:24:44 +0900845 return rq->__data_len;
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900846}
847
848static inline int blk_rq_cur_bytes(const struct request *rq)
849{
850 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
851}
Tejun Heo5efccd12009-04-23 11:05:18 +0900852
Tejun Heo80a761f2009-07-03 17:48:17 +0900853extern unsigned int blk_rq_err_bytes(const struct request *rq);
854
Tejun Heo5b936292009-05-07 22:24:38 +0900855static inline unsigned int blk_rq_sectors(const struct request *rq)
856{
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900857 return blk_rq_bytes(rq) >> 9;
Tejun Heo5b936292009-05-07 22:24:38 +0900858}
859
860static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
861{
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900862 return blk_rq_cur_bytes(rq) >> 9;
Tejun Heo5b936292009-05-07 22:24:38 +0900863}
864
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400865static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
866 unsigned int cmd_flags)
867{
868 if (unlikely(cmd_flags & REQ_DISCARD))
James Bottomley871dd922013-04-24 08:52:50 -0600869 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400870
Martin K. Petersen4363ac72012-09-18 12:19:27 -0400871 if (unlikely(cmd_flags & REQ_WRITE_SAME))
872 return q->limits.max_write_same_sectors;
873
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400874 return q->limits.max_sectors;
875}
876
Jens Axboe762380a2014-06-05 13:38:39 -0600877/*
878 * Return maximum size of a request at given offset. Only valid for
879 * file system requests.
880 */
881static inline unsigned int blk_max_size_offset(struct request_queue *q,
882 sector_t offset)
883{
884 if (!q->limits.chunk_sectors)
Jens Axboe736ed4d2014-06-17 22:09:29 -0700885 return q->limits.max_sectors;
Jens Axboe762380a2014-06-05 13:38:39 -0600886
887 return q->limits.chunk_sectors -
888 (offset & (q->limits.chunk_sectors - 1));
889}
890
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400891static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
892{
893 struct request_queue *q = rq->q;
894
895 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
896 return q->limits.max_hw_sectors;
897
Jens Axboee548ca42015-05-29 13:11:32 -0600898 if (!q->limits.chunk_sectors || (rq->cmd_flags & REQ_DISCARD))
Jens Axboe762380a2014-06-05 13:38:39 -0600899 return blk_queue_get_max_sectors(q, rq->cmd_flags);
900
901 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
902 blk_queue_get_max_sectors(q, rq->cmd_flags));
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400903}
904
Jun'ichi Nomura75afb352013-09-21 13:57:47 -0600905static inline unsigned int blk_rq_count_bios(struct request *rq)
906{
907 unsigned int nr_bios = 0;
908 struct bio *bio;
909
910 __rq_for_each_bio(bio, rq)
911 nr_bios++;
912
913 return nr_bios;
914}
915
Tejun Heo5efccd12009-04-23 11:05:18 +0900916/*
Tejun Heo9934c8c2009-05-08 11:54:16 +0900917 * Request issue related functions.
918 */
919extern struct request *blk_peek_request(struct request_queue *q);
920extern void blk_start_request(struct request *rq);
921extern struct request *blk_fetch_request(struct request_queue *q);
922
923/*
Tejun Heo2e60e022009-04-23 11:05:18 +0900924 * Request completion related functions.
925 *
926 * blk_update_request() completes given number of bytes and updates
927 * the request without completing it.
928 *
Tejun Heof06d9a22009-04-23 11:05:19 +0900929 * blk_end_request() and friends. __blk_end_request() must be called
930 * with the request queue spinlock acquired.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931 *
932 * Several drivers define their own end_request and call
Kiyoshi Ueda3bcddea2007-12-11 17:52:28 -0500933 * blk_end_request() for parts of the original function.
934 * This prevents code duplication in drivers.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700935 */
Tejun Heo2e60e022009-04-23 11:05:18 +0900936extern bool blk_update_request(struct request *rq, int error,
937 unsigned int nr_bytes);
Christoph Hellwig12120072014-04-16 09:44:59 +0200938extern void blk_finish_request(struct request *rq, int error);
FUJITA Tomonorib1f74492009-05-11 17:56:09 +0900939extern bool blk_end_request(struct request *rq, int error,
940 unsigned int nr_bytes);
941extern void blk_end_request_all(struct request *rq, int error);
942extern bool blk_end_request_cur(struct request *rq, int error);
Tejun Heo80a761f2009-07-03 17:48:17 +0900943extern bool blk_end_request_err(struct request *rq, int error);
FUJITA Tomonorib1f74492009-05-11 17:56:09 +0900944extern bool __blk_end_request(struct request *rq, int error,
945 unsigned int nr_bytes);
946extern void __blk_end_request_all(struct request *rq, int error);
947extern bool __blk_end_request_cur(struct request *rq, int error);
Tejun Heo80a761f2009-07-03 17:48:17 +0900948extern bool __blk_end_request_err(struct request *rq, int error);
Tejun Heo2e60e022009-04-23 11:05:18 +0900949
Jens Axboeff856ba2006-01-09 16:02:34 +0100950extern void blk_complete_request(struct request *);
Jens Axboe242f9dc2008-09-14 05:55:09 -0700951extern void __blk_complete_request(struct request *);
952extern void blk_abort_request(struct request *);
James Bottomley28018c22010-07-01 19:49:17 +0900953extern void blk_unprep_request(struct request *);
Jens Axboeff856ba2006-01-09 16:02:34 +0100954
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956 * Access functions for manipulating queue properties
957 */
Jens Axboe165125e2007-07-24 09:28:11 +0200958extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
Christoph Lameter19460892005-06-23 00:08:19 -0700959 spinlock_t *lock, int node_id);
Jens Axboe165125e2007-07-24 09:28:11 +0200960extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
Mike Snitzer01effb02010-05-11 08:57:42 +0200961extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
962 request_fn_proc *, spinlock_t *);
Jens Axboe165125e2007-07-24 09:28:11 +0200963extern void blk_cleanup_queue(struct request_queue *);
964extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
965extern void blk_queue_bounce_limit(struct request_queue *, u64);
Martin K. Petersen086fa5f2010-02-26 00:20:38 -0500966extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
Jens Axboe762380a2014-06-05 13:38:39 -0600967extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
Martin K. Petersen8a783622010-02-26 00:20:39 -0500968extern void blk_queue_max_segments(struct request_queue *, unsigned short);
Jens Axboe165125e2007-07-24 09:28:11 +0200969extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
Christoph Hellwig67efc922009-09-30 13:54:20 +0200970extern void blk_queue_max_discard_sectors(struct request_queue *q,
971 unsigned int max_discard_sectors);
Martin K. Petersen4363ac72012-09-18 12:19:27 -0400972extern void blk_queue_max_write_same_sectors(struct request_queue *q,
973 unsigned int max_write_same_sectors);
Martin K. Petersene1defc42009-05-22 17:17:49 -0400974extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
Martin K. Petersen892b6f92010-10-13 21:18:03 +0200975extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400976extern void blk_queue_alignment_offset(struct request_queue *q,
977 unsigned int alignment);
Martin K. Petersen7c958e32009-07-31 11:49:11 -0400978extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400979extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
Martin K. Petersen3c5820c2009-09-11 21:54:52 +0200980extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400981extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
Martin K. Petersene475bba2009-06-16 08:23:52 +0200982extern void blk_set_default_limits(struct queue_limits *lim);
Martin K. Petersenb1bd0552012-01-11 16:27:11 +0100983extern void blk_set_stacking_limits(struct queue_limits *lim);
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400984extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
985 sector_t offset);
Martin K. Petersen17be8c22010-01-11 03:21:49 -0500986extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
987 sector_t offset);
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400988extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
989 sector_t offset);
Jens Axboe165125e2007-07-24 09:28:11 +0200990extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
Tejun Heoe3790c72008-03-04 11:18:17 +0100991extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
FUJITA Tomonori27f82212008-07-04 09:30:03 +0200992extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
Tejun Heo2fb98e82008-02-19 11:36:53 +0100993extern int blk_queue_dma_drain(struct request_queue *q,
994 dma_drain_needed_fn *dma_drain_needed,
995 void *buf, unsigned int size);
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +0200996extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
Jens Axboe165125e2007-07-24 09:28:11 +0200997extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
Keith Busch03100aa2015-08-19 14:24:05 -0700998extern void blk_queue_virt_boundary(struct request_queue *, unsigned long);
Jens Axboe165125e2007-07-24 09:28:11 +0200999extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
James Bottomley28018c22010-07-01 19:49:17 +09001000extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
Jens Axboe165125e2007-07-24 09:28:11 +02001001extern void blk_queue_dma_alignment(struct request_queue *, int);
James Bottomley11c3e682007-12-31 16:37:00 -06001002extern void blk_queue_update_dma_alignment(struct request_queue *, int);
Jens Axboe165125e2007-07-24 09:28:11 +02001003extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
Jens Axboe242f9dc2008-09-14 05:55:09 -07001004extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1005extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
Tejun Heo4913efe2010-09-03 11:56:16 +02001006extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
shaohua.li@intel.comf3876932011-05-06 11:34:32 -06001007extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009
Jens Axboe165125e2007-07-24 09:28:11 +02001010extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011extern void blk_dump_rq_flags(struct request *, char *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012extern long nr_blockdev_pages(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001013
Tejun Heo09ac46c2011-12-14 00:33:38 +01001014bool __must_check blk_get_queue(struct request_queue *);
Jens Axboe165125e2007-07-24 09:28:11 +02001015struct request_queue *blk_alloc_queue(gfp_t);
1016struct request_queue *blk_alloc_queue_node(gfp_t, int);
1017extern void blk_put_queue(struct request_queue *);
Jens Axboe3f21c262015-06-05 10:57:37 -06001018extern void blk_set_queue_dying(struct request_queue *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019
Shaohua Li316cc672011-07-08 08:19:21 +02001020/*
Lin Ming6c954662013-03-23 11:42:26 +08001021 * block layer runtime pm functions
1022 */
Rafael J. Wysocki47fafbc2014-12-04 01:00:23 +01001023#ifdef CONFIG_PM
Lin Ming6c954662013-03-23 11:42:26 +08001024extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1025extern int blk_pre_runtime_suspend(struct request_queue *q);
1026extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1027extern void blk_pre_runtime_resume(struct request_queue *q);
1028extern void blk_post_runtime_resume(struct request_queue *q, int err);
1029#else
1030static inline void blk_pm_runtime_init(struct request_queue *q,
1031 struct device *dev) {}
1032static inline int blk_pre_runtime_suspend(struct request_queue *q)
1033{
1034 return -ENOSYS;
1035}
1036static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1037static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1038static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1039#endif
1040
1041/*
Suresh Jayaraman75df7132011-09-21 10:00:16 +02001042 * blk_plug permits building a queue of related requests by holding the I/O
1043 * fragments for a short period. This allows merging of sequential requests
1044 * into single larger request. As the requests are moved from a per-task list to
1045 * the device's request_queue in a batch, this results in improved scalability
1046 * as the lock contention for request_queue lock is reduced.
1047 *
1048 * It is ok not to disable preemption when adding the request to the plug list
1049 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1050 * the plug list when the task sleeps by itself. For details, please see
1051 * schedule() where blk_schedule_flush_plug() is called.
Shaohua Li316cc672011-07-08 08:19:21 +02001052 */
Jens Axboe73c10102011-03-08 13:19:51 +01001053struct blk_plug {
Suresh Jayaraman75df7132011-09-21 10:00:16 +02001054 struct list_head list; /* requests */
Jens Axboe320ae512013-10-24 09:20:05 +01001055 struct list_head mq_list; /* blk-mq requests */
Suresh Jayaraman75df7132011-09-21 10:00:16 +02001056 struct list_head cb_list; /* md requires an unplug callback */
Jens Axboe73c10102011-03-08 13:19:51 +01001057};
Shaohua Li55c022b2011-07-08 08:19:20 +02001058#define BLK_MAX_REQUEST_COUNT 16
1059
NeilBrown9cbb1752012-07-31 09:08:14 +02001060struct blk_plug_cb;
NeilBrown74018dc2012-07-31 09:08:15 +02001061typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
NeilBrown048c9372011-04-18 09:52:22 +02001062struct blk_plug_cb {
1063 struct list_head list;
NeilBrown9cbb1752012-07-31 09:08:14 +02001064 blk_plug_cb_fn callback;
1065 void *data;
NeilBrown048c9372011-04-18 09:52:22 +02001066};
NeilBrown9cbb1752012-07-31 09:08:14 +02001067extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1068 void *data, int size);
Jens Axboe73c10102011-03-08 13:19:51 +01001069extern void blk_start_plug(struct blk_plug *);
1070extern void blk_finish_plug(struct blk_plug *);
Jens Axboef6603782011-04-15 15:49:07 +02001071extern void blk_flush_plug_list(struct blk_plug *, bool);
Jens Axboe73c10102011-03-08 13:19:51 +01001072
1073static inline void blk_flush_plug(struct task_struct *tsk)
1074{
1075 struct blk_plug *plug = tsk->plug;
1076
Christoph Hellwig88b996c2011-04-15 15:20:10 +02001077 if (plug)
Jens Axboea237c1c2011-04-16 13:27:55 +02001078 blk_flush_plug_list(plug, false);
1079}
1080
1081static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1082{
1083 struct blk_plug *plug = tsk->plug;
1084
1085 if (plug)
Jens Axboef6603782011-04-15 15:49:07 +02001086 blk_flush_plug_list(plug, true);
Jens Axboe73c10102011-03-08 13:19:51 +01001087}
1088
1089static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1090{
1091 struct blk_plug *plug = tsk->plug;
1092
Jens Axboe320ae512013-10-24 09:20:05 +01001093 return plug &&
1094 (!list_empty(&plug->list) ||
1095 !list_empty(&plug->mq_list) ||
1096 !list_empty(&plug->cb_list));
Jens Axboe73c10102011-03-08 13:19:51 +01001097}
1098
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099/*
1100 * tag stuff
1101 */
Jens Axboe165125e2007-07-24 09:28:11 +02001102extern int blk_queue_start_tag(struct request_queue *, struct request *);
1103extern struct request *blk_queue_find_tag(struct request_queue *, int);
1104extern void blk_queue_end_tag(struct request_queue *, struct request *);
Shaohua Liee1b6f72015-01-15 17:32:25 -08001105extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *, int);
Jens Axboe165125e2007-07-24 09:28:11 +02001106extern void blk_queue_free_tags(struct request_queue *);
1107extern int blk_queue_resize_tags(struct request_queue *, int);
1108extern void blk_queue_invalidate_tags(struct request_queue *);
Shaohua Liee1b6f72015-01-15 17:32:25 -08001109extern struct blk_queue_tag *blk_init_tags(int, int);
James Bottomley492dfb42006-08-30 15:48:45 -04001110extern void blk_free_tags(struct blk_queue_tag *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001111
David C Somayajuluf583f492006-10-04 08:27:25 +02001112static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1113 int tag)
1114{
1115 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1116 return NULL;
1117 return bqt->tag_index[tag];
1118}
Christoph Hellwigdd3932e2010-09-16 20:51:46 +02001119
1120#define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1121
1122extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
Dmitry Monakhovfbd9b092010-04-28 17:55:06 +04001123extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1124 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
Martin K. Petersen4363ac72012-09-18 12:19:27 -04001125extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1126 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
Dmitry Monakhov3f14d792010-04-28 17:55:09 +04001127extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
Martin K. Petersend93ba7a2015-01-20 20:06:30 -05001128 sector_t nr_sects, gfp_t gfp_mask, bool discard);
Christoph Hellwig2cf6d262010-08-18 05:29:10 -04001129static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1130 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
David Woodhousefb2dce82008-08-05 18:01:53 +01001131{
Christoph Hellwig2cf6d262010-08-18 05:29:10 -04001132 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1133 nr_blocks << (sb->s_blocksize_bits - 9),
1134 gfp_mask, flags);
David Woodhousefb2dce82008-08-05 18:01:53 +01001135}
Lukas Czernere6fa0be2010-10-27 21:30:04 -04001136static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
Theodore Ts'oa107e5a2010-10-27 23:44:47 -04001137 sector_t nr_blocks, gfp_t gfp_mask)
Lukas Czernere6fa0be2010-10-27 21:30:04 -04001138{
1139 return blkdev_issue_zeroout(sb->s_bdev,
1140 block << (sb->s_blocksize_bits - 9),
1141 nr_blocks << (sb->s_blocksize_bits - 9),
Martin K. Petersend93ba7a2015-01-20 20:06:30 -05001142 gfp_mask, true);
Lukas Czernere6fa0be2010-10-27 21:30:04 -04001143}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001144
Jens Axboe018e0442009-06-26 16:27:10 +02001145extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
Adel Gadllah0b07de82008-06-26 13:48:27 +02001146
Martin K. Peterseneb28d312010-02-26 00:20:37 -05001147enum blk_default_limits {
1148 BLK_MAX_SEGMENTS = 128,
1149 BLK_SAFE_MAX_SECTORS = 255,
Jeff Moyerd2be5372015-08-13 14:57:57 -04001150 BLK_DEF_MAX_SECTORS = 2560,
Martin K. Peterseneb28d312010-02-26 00:20:37 -05001151 BLK_MAX_SEGMENT_SIZE = 65536,
1152 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1153};
Milan Broz0e435ac2008-12-03 12:55:08 +01001154
Linus Torvalds1da177e2005-04-16 15:20:36 -07001155#define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1156
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001157static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1158{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001159 return q->limits.bounce_pfn;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001160}
1161
1162static inline unsigned long queue_segment_boundary(struct request_queue *q)
1163{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001164 return q->limits.seg_boundary_mask;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001165}
1166
Keith Busch03100aa2015-08-19 14:24:05 -07001167static inline unsigned long queue_virt_boundary(struct request_queue *q)
1168{
1169 return q->limits.virt_boundary_mask;
1170}
1171
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001172static inline unsigned int queue_max_sectors(struct request_queue *q)
1173{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001174 return q->limits.max_sectors;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001175}
1176
1177static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1178{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001179 return q->limits.max_hw_sectors;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001180}
1181
Martin K. Petersen8a783622010-02-26 00:20:39 -05001182static inline unsigned short queue_max_segments(struct request_queue *q)
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001183{
Martin K. Petersen8a783622010-02-26 00:20:39 -05001184 return q->limits.max_segments;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001185}
1186
1187static inline unsigned int queue_max_segment_size(struct request_queue *q)
1188{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001189 return q->limits.max_segment_size;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001190}
1191
Martin K. Petersene1defc42009-05-22 17:17:49 -04001192static inline unsigned short queue_logical_block_size(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001193{
1194 int retval = 512;
1195
Martin K. Petersen025146e2009-05-22 17:17:51 -04001196 if (q && q->limits.logical_block_size)
1197 retval = q->limits.logical_block_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001198
1199 return retval;
1200}
1201
Martin K. Petersene1defc42009-05-22 17:17:49 -04001202static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001203{
Martin K. Petersene1defc42009-05-22 17:17:49 -04001204 return queue_logical_block_size(bdev_get_queue(bdev));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001205}
1206
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001207static inline unsigned int queue_physical_block_size(struct request_queue *q)
1208{
1209 return q->limits.physical_block_size;
1210}
1211
Martin K. Petersen892b6f92010-10-13 21:18:03 +02001212static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
Martin K. Petersenac481c22009-10-03 20:52:01 +02001213{
1214 return queue_physical_block_size(bdev_get_queue(bdev));
1215}
1216
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001217static inline unsigned int queue_io_min(struct request_queue *q)
1218{
1219 return q->limits.io_min;
1220}
1221
Martin K. Petersenac481c22009-10-03 20:52:01 +02001222static inline int bdev_io_min(struct block_device *bdev)
1223{
1224 return queue_io_min(bdev_get_queue(bdev));
1225}
1226
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001227static inline unsigned int queue_io_opt(struct request_queue *q)
1228{
1229 return q->limits.io_opt;
1230}
1231
Martin K. Petersenac481c22009-10-03 20:52:01 +02001232static inline int bdev_io_opt(struct block_device *bdev)
1233{
1234 return queue_io_opt(bdev_get_queue(bdev));
1235}
1236
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001237static inline int queue_alignment_offset(struct request_queue *q)
1238{
Martin K. Petersenac481c22009-10-03 20:52:01 +02001239 if (q->limits.misaligned)
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001240 return -1;
1241
Martin K. Petersenac481c22009-10-03 20:52:01 +02001242 return q->limits.alignment_offset;
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001243}
1244
Martin K. Petersene03a72e2010-01-11 03:21:51 -05001245static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
Martin K. Petersen81744ee2009-12-29 08:35:35 +01001246{
1247 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
Mike Snitzerb8839b82014-10-08 18:26:13 -04001248 unsigned int alignment = sector_div(sector, granularity >> 9) << 9;
Martin K. Petersen81744ee2009-12-29 08:35:35 +01001249
Mike Snitzerb8839b82014-10-08 18:26:13 -04001250 return (granularity + lim->alignment_offset - alignment) % granularity;
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001251}
1252
Martin K. Petersenac481c22009-10-03 20:52:01 +02001253static inline int bdev_alignment_offset(struct block_device *bdev)
1254{
1255 struct request_queue *q = bdev_get_queue(bdev);
1256
1257 if (q->limits.misaligned)
1258 return -1;
1259
1260 if (bdev != bdev->bd_contains)
1261 return bdev->bd_part->alignment_offset;
1262
1263 return q->limits.alignment_offset;
1264}
1265
Martin K. Petersen86b37282009-11-10 11:50:21 +01001266static inline int queue_discard_alignment(struct request_queue *q)
1267{
1268 if (q->limits.discard_misaligned)
1269 return -1;
1270
1271 return q->limits.discard_alignment;
1272}
1273
Martin K. Petersene03a72e2010-01-11 03:21:51 -05001274static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
Martin K. Petersen86b37282009-11-10 11:50:21 +01001275{
Linus Torvalds59771072012-12-19 07:18:35 -08001276 unsigned int alignment, granularity, offset;
Martin K. Petersendd3d1452010-01-11 03:21:48 -05001277
Martin K. Petersena934a002011-05-18 10:37:35 +02001278 if (!lim->max_discard_sectors)
1279 return 0;
1280
Linus Torvalds59771072012-12-19 07:18:35 -08001281 /* Why are these in bytes, not sectors? */
1282 alignment = lim->discard_alignment >> 9;
1283 granularity = lim->discard_granularity >> 9;
1284 if (!granularity)
1285 return 0;
1286
1287 /* Offset of the partition start in 'granularity' sectors */
1288 offset = sector_div(sector, granularity);
1289
1290 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1291 offset = (granularity + alignment - offset) % granularity;
1292
1293 /* Turn it back into bytes, gaah */
1294 return offset << 9;
Martin K. Petersen86b37282009-11-10 11:50:21 +01001295}
1296
Paolo Bonzinic6e66632012-08-02 09:48:50 +02001297static inline int bdev_discard_alignment(struct block_device *bdev)
1298{
1299 struct request_queue *q = bdev_get_queue(bdev);
1300
1301 if (bdev != bdev->bd_contains)
1302 return bdev->bd_part->discard_alignment;
1303
1304 return q->limits.discard_alignment;
1305}
1306
Martin K. Petersen98262f22009-12-03 09:24:48 +01001307static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1308{
Martin K. Petersena934a002011-05-18 10:37:35 +02001309 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
Martin K. Petersen98262f22009-12-03 09:24:48 +01001310 return 1;
1311
1312 return 0;
1313}
1314
1315static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1316{
1317 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1318}
1319
Martin K. Petersen4363ac72012-09-18 12:19:27 -04001320static inline unsigned int bdev_write_same(struct block_device *bdev)
1321{
1322 struct request_queue *q = bdev_get_queue(bdev);
1323
1324 if (q)
1325 return q->limits.max_write_same_sectors;
1326
1327 return 0;
1328}
1329
Jens Axboe165125e2007-07-24 09:28:11 +02001330static inline int queue_dma_alignment(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331{
Pete Wyckoff482eb682008-01-01 10:23:02 -05001332 return q ? q->dma_alignment : 511;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001333}
1334
Namhyung Kim14417792010-09-15 13:08:27 +02001335static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
FUJITA Tomonori87904072008-08-28 15:05:58 +09001336 unsigned int len)
1337{
1338 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
Namhyung Kim14417792010-09-15 13:08:27 +02001339 return !(addr & alignment) && !(len & alignment);
FUJITA Tomonori87904072008-08-28 15:05:58 +09001340}
1341
Linus Torvalds1da177e2005-04-16 15:20:36 -07001342/* assumes size > 256 */
1343static inline unsigned int blksize_bits(unsigned int size)
1344{
1345 unsigned int bits = 8;
1346 do {
1347 bits++;
1348 size >>= 1;
1349 } while (size > 256);
1350 return bits;
1351}
1352
Adrian Bunk2befb9e2005-09-10 00:27:17 -07001353static inline unsigned int block_size(struct block_device *bdev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001354{
1355 return bdev->bd_block_size;
1356}
1357
shaohua.li@intel.comf3876932011-05-06 11:34:32 -06001358static inline bool queue_flush_queueable(struct request_queue *q)
1359{
1360 return !q->flush_not_queueable;
1361}
1362
Linus Torvalds1da177e2005-04-16 15:20:36 -07001363typedef struct {struct page *v;} Sector;
1364
1365unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1366
1367static inline void put_dev_sector(Sector p)
1368{
1369 page_cache_release(p.v);
1370}
1371
Keith Busch03100aa2015-08-19 14:24:05 -07001372/*
1373 * Check if adding a bio_vec after bprv with offset would create a gap in
1374 * the SG list. Most drivers don't care about this, but some do.
1375 */
1376static inline bool bvec_gap_to_prev(struct request_queue *q,
1377 struct bio_vec *bprv, unsigned int offset)
1378{
1379 if (!queue_virt_boundary(q))
1380 return false;
1381 return offset ||
1382 ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q));
1383}
1384
Jens Axboe5e7c4272015-09-03 19:28:20 +03001385static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
1386 struct bio *next)
1387{
1388 if (!bio_has_data(prev))
1389 return false;
1390
1391 return bvec_gap_to_prev(q, &prev->bi_io_vec[prev->bi_vcnt - 1],
1392 next->bi_io_vec[0].bv_offset);
1393}
1394
1395static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
1396{
1397 return bio_will_gap(req->q, req->biotail, bio);
1398}
1399
1400static inline bool req_gap_front_merge(struct request *req, struct bio *bio)
1401{
1402 return bio_will_gap(req->q, bio, req->bio);
1403}
1404
Linus Torvalds1da177e2005-04-16 15:20:36 -07001405struct work_struct;
Jens Axboe59c3d452014-04-08 09:15:35 -06001406int kblockd_schedule_work(struct work_struct *work);
1407int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
Jens Axboe8ab14592014-04-08 09:17:40 -06001408int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001409
Divyesh Shah91952912010-04-01 15:01:41 -07001410#ifdef CONFIG_BLK_CGROUP
Jens Axboe28f41972010-06-01 12:23:18 +02001411/*
1412 * This should not be using sched_clock(). A real patch is in progress
1413 * to fix this up, until that is in place we need to disable preemption
1414 * around sched_clock() in this function and set_io_start_time_ns().
1415 */
Divyesh Shah91952912010-04-01 15:01:41 -07001416static inline void set_start_time_ns(struct request *req)
1417{
Jens Axboe28f41972010-06-01 12:23:18 +02001418 preempt_disable();
Divyesh Shah91952912010-04-01 15:01:41 -07001419 req->start_time_ns = sched_clock();
Jens Axboe28f41972010-06-01 12:23:18 +02001420 preempt_enable();
Divyesh Shah91952912010-04-01 15:01:41 -07001421}
1422
1423static inline void set_io_start_time_ns(struct request *req)
1424{
Jens Axboe28f41972010-06-01 12:23:18 +02001425 preempt_disable();
Divyesh Shah91952912010-04-01 15:01:41 -07001426 req->io_start_time_ns = sched_clock();
Jens Axboe28f41972010-06-01 12:23:18 +02001427 preempt_enable();
Divyesh Shah91952912010-04-01 15:01:41 -07001428}
Divyesh Shah84c124d2010-04-09 08:31:19 +02001429
1430static inline uint64_t rq_start_time_ns(struct request *req)
1431{
1432 return req->start_time_ns;
1433}
1434
1435static inline uint64_t rq_io_start_time_ns(struct request *req)
1436{
1437 return req->io_start_time_ns;
1438}
Divyesh Shah91952912010-04-01 15:01:41 -07001439#else
1440static inline void set_start_time_ns(struct request *req) {}
1441static inline void set_io_start_time_ns(struct request *req) {}
Divyesh Shah84c124d2010-04-09 08:31:19 +02001442static inline uint64_t rq_start_time_ns(struct request *req)
1443{
1444 return 0;
1445}
1446static inline uint64_t rq_io_start_time_ns(struct request *req)
1447{
1448 return 0;
1449}
Divyesh Shah91952912010-04-01 15:01:41 -07001450#endif
1451
Linus Torvalds1da177e2005-04-16 15:20:36 -07001452#define MODULE_ALIAS_BLOCKDEV(major,minor) \
1453 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1454#define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1455 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1456
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001457#if defined(CONFIG_BLK_DEV_INTEGRITY)
1458
Martin K. Petersen8288f492014-09-26 19:20:02 -04001459enum blk_integrity_flags {
1460 BLK_INTEGRITY_VERIFY = 1 << 0,
1461 BLK_INTEGRITY_GENERATE = 1 << 1,
Martin K. Petersen3aec2f42014-09-26 19:20:03 -04001462 BLK_INTEGRITY_DEVICE_CAPABLE = 1 << 2,
Martin K. Petersenaae7df52014-09-26 19:20:05 -04001463 BLK_INTEGRITY_IP_CHECKSUM = 1 << 3,
Martin K. Petersen8288f492014-09-26 19:20:02 -04001464};
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001465
Martin K. Petersen18593082014-09-26 19:20:01 -04001466struct blk_integrity_iter {
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001467 void *prot_buf;
1468 void *data_buf;
Martin K. Petersen3be91c42014-09-26 19:19:59 -04001469 sector_t seed;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001470 unsigned int data_size;
Martin K. Petersen3be91c42014-09-26 19:19:59 -04001471 unsigned short interval;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001472 const char *disk_name;
1473};
1474
Martin K. Petersen18593082014-09-26 19:20:01 -04001475typedef int (integrity_processing_fn) (struct blk_integrity_iter *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001476
Martin K. Petersen0f8087e2015-10-21 13:19:33 -04001477struct blk_integrity_profile {
1478 integrity_processing_fn *generate_fn;
1479 integrity_processing_fn *verify_fn;
1480 const char *name;
1481};
1482
Martin K. Petersen25520d52015-10-21 13:19:49 -04001483extern void blk_integrity_register(struct gendisk *, struct blk_integrity *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001484extern void blk_integrity_unregister(struct gendisk *);
Martin K. Petersenad7fce92008-10-01 03:38:39 -04001485extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
Martin K. Petersen13f05c82010-09-10 20:50:10 +02001486extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1487 struct scatterlist *);
1488extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
Martin K. Petersen4eaf99b2014-09-26 19:20:06 -04001489extern bool blk_integrity_merge_rq(struct request_queue *, struct request *,
1490 struct request *);
1491extern bool blk_integrity_merge_bio(struct request_queue *, struct request *,
1492 struct bio *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001493
Martin K. Petersen25520d52015-10-21 13:19:49 -04001494static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1495{
Dan Williamsac6fc482015-10-21 13:20:18 -04001496 struct blk_integrity *bi = &disk->queue->integrity;
Martin K. Petersen25520d52015-10-21 13:19:49 -04001497
1498 if (!bi->profile)
1499 return NULL;
1500
1501 return bi;
1502}
1503
Jens Axboeb04accc2008-10-02 12:53:22 +02001504static inline
1505struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1506{
Martin K. Petersen25520d52015-10-21 13:19:49 -04001507 return blk_get_integrity(bdev->bd_disk);
Martin K. Petersenb02739b2008-10-02 18:47:49 +02001508}
1509
Martin K. Petersen180b2f92014-09-26 19:19:56 -04001510static inline bool blk_integrity_rq(struct request *rq)
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001511{
Martin K. Petersen180b2f92014-09-26 19:19:56 -04001512 return rq->cmd_flags & REQ_INTEGRITY;
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001513}
1514
Martin K. Petersen13f05c82010-09-10 20:50:10 +02001515static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1516 unsigned int segs)
1517{
1518 q->limits.max_integrity_segments = segs;
1519}
1520
1521static inline unsigned short
1522queue_max_integrity_segments(struct request_queue *q)
1523{
1524 return q->limits.max_integrity_segments;
1525}
1526
Sagi Grimberg7f39add2015-09-11 09:03:04 -06001527static inline bool integrity_req_gap_back_merge(struct request *req,
1528 struct bio *next)
1529{
1530 struct bio_integrity_payload *bip = bio_integrity(req->bio);
1531 struct bio_integrity_payload *bip_next = bio_integrity(next);
1532
1533 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1534 bip_next->bip_vec[0].bv_offset);
1535}
1536
1537static inline bool integrity_req_gap_front_merge(struct request *req,
1538 struct bio *bio)
1539{
1540 struct bio_integrity_payload *bip = bio_integrity(bio);
1541 struct bio_integrity_payload *bip_next = bio_integrity(req->bio);
1542
1543 return bvec_gap_to_prev(req->q, &bip->bip_vec[bip->bip_vcnt - 1],
1544 bip_next->bip_vec[0].bv_offset);
1545}
1546
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001547#else /* CONFIG_BLK_DEV_INTEGRITY */
1548
Stephen Rothwellfd832402012-01-12 09:17:30 +01001549struct bio;
1550struct block_device;
1551struct gendisk;
1552struct blk_integrity;
1553
1554static inline int blk_integrity_rq(struct request *rq)
1555{
1556 return 0;
1557}
1558static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1559 struct bio *b)
1560{
1561 return 0;
1562}
1563static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1564 struct bio *b,
1565 struct scatterlist *s)
1566{
1567 return 0;
1568}
1569static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1570{
Michele Curti61a04e52014-10-09 15:30:17 -07001571 return NULL;
Stephen Rothwellfd832402012-01-12 09:17:30 +01001572}
1573static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1574{
1575 return NULL;
1576}
1577static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1578{
1579 return 0;
1580}
Martin K. Petersen25520d52015-10-21 13:19:49 -04001581static inline void blk_integrity_register(struct gendisk *d,
Stephen Rothwellfd832402012-01-12 09:17:30 +01001582 struct blk_integrity *b)
1583{
Stephen Rothwellfd832402012-01-12 09:17:30 +01001584}
1585static inline void blk_integrity_unregister(struct gendisk *d)
1586{
1587}
1588static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1589 unsigned int segs)
1590{
1591}
1592static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1593{
1594 return 0;
1595}
Martin K. Petersen4eaf99b2014-09-26 19:20:06 -04001596static inline bool blk_integrity_merge_rq(struct request_queue *rq,
1597 struct request *r1,
1598 struct request *r2)
Stephen Rothwellfd832402012-01-12 09:17:30 +01001599{
Martin K. Petersencb1a5ab2014-10-28 20:27:43 -06001600 return true;
Stephen Rothwellfd832402012-01-12 09:17:30 +01001601}
Martin K. Petersen4eaf99b2014-09-26 19:20:06 -04001602static inline bool blk_integrity_merge_bio(struct request_queue *rq,
1603 struct request *r,
1604 struct bio *b)
Stephen Rothwellfd832402012-01-12 09:17:30 +01001605{
Martin K. Petersencb1a5ab2014-10-28 20:27:43 -06001606 return true;
Stephen Rothwellfd832402012-01-12 09:17:30 +01001607}
Martin K. Petersen25520d52015-10-21 13:19:49 -04001608
Sagi Grimberg7f39add2015-09-11 09:03:04 -06001609static inline bool integrity_req_gap_back_merge(struct request *req,
1610 struct bio *next)
1611{
1612 return false;
1613}
1614static inline bool integrity_req_gap_front_merge(struct request *req,
1615 struct bio *bio)
1616{
1617 return false;
1618}
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001619
1620#endif /* CONFIG_BLK_DEV_INTEGRITY */
1621
Dan Williamsb2e0d162016-01-15 16:55:59 -08001622/**
1623 * struct blk_dax_ctl - control and output parameters for ->direct_access
1624 * @sector: (input) offset relative to a block_device
1625 * @addr: (output) kernel virtual address for @sector populated by driver
1626 * @pfn: (output) page frame number for @addr populated by driver
1627 * @size: (input) number of bytes requested
1628 */
1629struct blk_dax_ctl {
1630 sector_t sector;
1631 void __pmem *addr;
1632 long size;
Dan Williams34c0fd52016-01-15 16:56:14 -08001633 pfn_t pfn;
Dan Williamsb2e0d162016-01-15 16:55:59 -08001634};
1635
Al Viro08f85852007-10-08 13:26:20 -04001636struct block_device_operations {
Al Virod4430d622008-03-02 09:09:22 -05001637 int (*open) (struct block_device *, fmode_t);
Al Virodb2a1442013-05-05 21:52:57 -04001638 void (*release) (struct gendisk *, fmode_t);
Matthew Wilcox47a191f2014-06-04 16:07:46 -07001639 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
Al Virod4430d622008-03-02 09:09:22 -05001640 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1641 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
Ross Zwislere2e05392015-08-18 13:55:41 -06001642 long (*direct_access)(struct block_device *, sector_t, void __pmem **,
Dan Williams34c0fd52016-01-15 16:56:14 -08001643 pfn_t *);
Tejun Heo77ea8872010-12-08 20:57:37 +01001644 unsigned int (*check_events) (struct gendisk *disk,
1645 unsigned int clearing);
1646 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
Al Viro08f85852007-10-08 13:26:20 -04001647 int (*media_changed) (struct gendisk *);
Tejun Heoc3e33e02010-05-15 20:09:29 +02001648 void (*unlock_native_capacity) (struct gendisk *);
Al Viro08f85852007-10-08 13:26:20 -04001649 int (*revalidate_disk) (struct gendisk *);
1650 int (*getgeo)(struct block_device *, struct hd_geometry *);
Nitin Guptab3a27d02010-05-17 11:02:43 +05301651 /* this callback is with swap_lock and sometimes page table lock held */
1652 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
Al Viro08f85852007-10-08 13:26:20 -04001653 struct module *owner;
Christoph Hellwigbbd3e062015-10-15 14:10:48 +02001654 const struct pr_ops *pr_ops;
Al Viro08f85852007-10-08 13:26:20 -04001655};
1656
Al Viro633a08b2007-08-29 20:34:12 -04001657extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1658 unsigned long);
Matthew Wilcox47a191f2014-06-04 16:07:46 -07001659extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1660extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1661 struct writeback_control *);
Dan Williamsb2e0d162016-01-15 16:55:59 -08001662extern long bdev_direct_access(struct block_device *, struct blk_dax_ctl *);
David Howells93614012006-09-30 20:45:40 +02001663#else /* CONFIG_BLOCK */
Fabian Frederickac13a822014-06-04 16:06:27 -07001664
1665struct block_device;
1666
David Howells93614012006-09-30 20:45:40 +02001667/*
1668 * stubs for when the block layer is configured out
1669 */
1670#define buffer_heads_over_limit 0
1671
David Howells93614012006-09-30 20:45:40 +02001672static inline long nr_blockdev_pages(void)
1673{
1674 return 0;
1675}
1676
Jens Axboe1f940bd2011-03-11 20:17:08 +01001677struct blk_plug {
1678};
1679
1680static inline void blk_start_plug(struct blk_plug *plug)
Jens Axboe73c10102011-03-08 13:19:51 +01001681{
1682}
1683
Jens Axboe1f940bd2011-03-11 20:17:08 +01001684static inline void blk_finish_plug(struct blk_plug *plug)
Jens Axboe73c10102011-03-08 13:19:51 +01001685{
1686}
1687
Jens Axboe1f940bd2011-03-11 20:17:08 +01001688static inline void blk_flush_plug(struct task_struct *task)
Jens Axboe73c10102011-03-08 13:19:51 +01001689{
1690}
1691
Jens Axboea237c1c2011-04-16 13:27:55 +02001692static inline void blk_schedule_flush_plug(struct task_struct *task)
1693{
1694}
1695
1696
Jens Axboe73c10102011-03-08 13:19:51 +01001697static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1698{
1699 return false;
1700}
1701
Fabian Frederickac13a822014-06-04 16:06:27 -07001702static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1703 sector_t *error_sector)
1704{
1705 return 0;
1706}
1707
David Howells93614012006-09-30 20:45:40 +02001708#endif /* CONFIG_BLOCK */
1709
Linus Torvalds1da177e2005-04-16 15:20:36 -07001710#endif