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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>
15#include <linux/backing-dev.h>
16#include <linux/wait.h>
17#include <linux/mempool.h>
18#include <linux/bio.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/stringify.h>
Hugh Dickins3e6053d2008-09-11 10:57:55 +020020#include <linux/gfp.h>
FUJITA Tomonorid351af02007-07-09 12:40:35 +020021#include <linux/bsg.h>
Jens Axboec7c22e42008-09-13 20:26:01 +020022#include <linux/smp.h>
Tejun Heo548bc8e2013-01-09 08:05:13 -080023#include <linux/rcupdate.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024
25#include <asm/scatterlist.h>
26
Paul Gortmakerde477252011-05-26 13:46:22 -040027struct module;
Christoph Hellwig21b2f0c2006-03-22 17:52:04 +010028struct scsi_ioctl_command;
29
Linus Torvalds1da177e2005-04-16 15:20:36 -070030struct request_queue;
Linus Torvalds1da177e2005-04-16 15:20:36 -070031struct elevator_queue;
Linus Torvalds1da177e2005-04-16 15:20:36 -070032struct request_pm_state;
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;
Linus Torvalds1da177e2005-04-16 15:20:36 -070038
39#define BLKDEV_MIN_RQ 4
40#define BLKDEV_MAX_RQ 128 /* Default maximum */
41
Tejun Heo8bd435b2012-04-13 13:11:28 -070042/*
43 * Maximum number of blkcg policies allowed to be registered concurrently.
44 * Defined here to simplify include dependency.
45 */
46#define BLKCG_MAX_POLS 2
47
Linus Torvalds1da177e2005-04-16 15:20:36 -070048struct request;
Tejun Heo8ffdc652006-01-06 09:49:03 +010049typedef void (rq_end_io_fn)(struct request *, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
Tejun Heo5b788ce2012-06-04 20:40:59 -070051#define BLK_RL_SYNCFULL (1U << 0)
52#define BLK_RL_ASYNCFULL (1U << 1)
53
Linus Torvalds1da177e2005-04-16 15:20:36 -070054struct request_list {
Tejun Heo5b788ce2012-06-04 20:40:59 -070055 struct request_queue *q; /* the queue this rl belongs to */
Tejun Heoa0516612012-06-26 15:05:44 -070056#ifdef CONFIG_BLK_CGROUP
57 struct blkcg_gq *blkg; /* blkg this request pool belongs to */
58#endif
Jens Axboe1faa16d2009-04-06 14:48:01 +020059 /*
60 * count[], starved[], and wait[] are indexed by
61 * BLK_RW_SYNC/BLK_RW_ASYNC
62 */
Tejun Heo8a5ecdd2012-06-04 20:40:58 -070063 int count[2];
64 int starved[2];
65 mempool_t *rq_pool;
66 wait_queue_head_t wait[2];
Tejun Heo5b788ce2012-06-04 20:40:59 -070067 unsigned int flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -070068};
69
Jens Axboe4aff5e22006-08-10 08:44:47 +020070/*
71 * request command types
72 */
73enum rq_cmd_type_bits {
74 REQ_TYPE_FS = 1, /* fs request */
75 REQ_TYPE_BLOCK_PC, /* scsi command */
76 REQ_TYPE_SENSE, /* sense request */
77 REQ_TYPE_PM_SUSPEND, /* suspend request */
78 REQ_TYPE_PM_RESUME, /* resume request */
79 REQ_TYPE_PM_SHUTDOWN, /* shutdown request */
Jens Axboe4aff5e22006-08-10 08:44:47 +020080 REQ_TYPE_SPECIAL, /* driver defined type */
Jens Axboe4aff5e22006-08-10 08:44:47 +020081 /*
82 * for ATA/ATAPI devices. this really doesn't belong here, ide should
83 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
84 * private REQ_LB opcodes to differentiate what type of request this is
85 */
Jens Axboe4aff5e22006-08-10 08:44:47 +020086 REQ_TYPE_ATA_TASKFILE,
Jens Axboecea28852006-10-12 15:08:45 +020087 REQ_TYPE_ATA_PC,
Jens Axboe4aff5e22006-08-10 08:44:47 +020088};
89
Linus Torvalds1da177e2005-04-16 15:20:36 -070090#define BLK_MAX_CDB 16
91
92/*
Christoph Hellwigaf76e552014-05-06 12:12:45 +020093 * Try to put the fields that are referenced together in the same cacheline.
94 *
95 * If you modify this structure, make sure to update blk_rq_init() and
96 * especially blk_mq_rq_ctx_init() to take care of the added fields.
Linus Torvalds1da177e2005-04-16 15:20:36 -070097 */
98struct request {
Christoph Hellwig6897fc22014-01-30 15:45:47 -080099 struct list_head queuelist;
Jens Axboe320ae512013-10-24 09:20:05 +0100100 union {
101 struct call_single_data csd;
Jan Kara8b4922d2014-02-24 16:39:52 +0100102 unsigned long fifo_time;
Jens Axboe320ae512013-10-24 09:20:05 +0100103 };
Jens Axboeff856ba2006-01-09 16:02:34 +0100104
Jens Axboe165125e2007-07-24 09:28:11 +0200105 struct request_queue *q;
Jens Axboe320ae512013-10-24 09:20:05 +0100106 struct blk_mq_ctx *mq_ctx;
Jens Axboee6a1c872006-08-10 09:00:21 +0200107
Jens Axboe59533162013-05-23 12:25:08 +0200108 u64 cmd_flags;
Jens Axboe4aff5e22006-08-10 08:44:47 +0200109 enum rq_cmd_type_bits cmd_type;
Jens Axboe242f9dc2008-09-14 05:55:09 -0700110 unsigned long atomic_flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700111
Richard Kennedy181fdde2010-03-19 08:58:16 +0100112 int cpu;
113
Tejun Heoa2dec7b2009-05-07 22:24:44 +0900114 /* the following two fields are internal, NEVER access directly */
Tejun Heoa2dec7b2009-05-07 22:24:44 +0900115 unsigned int __data_len; /* total data len */
Richard Kennedy181fdde2010-03-19 08:58:16 +0100116 sector_t __sector; /* sector cursor */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117
118 struct bio *bio;
119 struct bio *biotail;
120
Jens Axboe360f92c2014-04-09 20:27:01 -0600121 /*
122 * The hash is used inside the scheduler, and killed once the
123 * request reaches the dispatch list. The ipi_list is only used
124 * to queue the request for softirq completion, which is long
125 * after the request has been unhashed (and even removed from
126 * the dispatch list).
127 */
128 union {
129 struct hlist_node hash; /* merge hash */
130 struct list_head ipi_list;
131 };
132
Jens Axboee6a1c872006-08-10 09:00:21 +0200133 /*
134 * The rb_node is only used inside the io scheduler, requests
135 * are pruned when moved to the dispatch queue. So let the
Mike Snitzerc1867942011-02-11 11:08:00 +0100136 * completion_data share space with the rb_node.
Jens Axboee6a1c872006-08-10 09:00:21 +0200137 */
138 union {
139 struct rb_node rb_node; /* sort/lookup */
Mike Snitzerc1867942011-02-11 11:08:00 +0100140 void *completion_data;
Jens Axboee6a1c872006-08-10 09:00:21 +0200141 };
Jens Axboe98170642006-07-28 09:23:08 +0200142
Jens Axboeff7d1452006-07-12 14:04:37 +0200143 /*
Vivek Goyal7f1dc8a2010-04-21 17:44:16 +0200144 * Three pointers are available for the IO schedulers, if they need
Mike Snitzerc1867942011-02-11 11:08:00 +0100145 * more they have to dynamically allocate it. Flush requests are
146 * never put on the IO scheduler. So let the flush fields share
Tejun Heoa612fdd2011-12-14 00:33:41 +0100147 * space with the elevator data.
Jens Axboeff7d1452006-07-12 14:04:37 +0200148 */
Mike Snitzerc1867942011-02-11 11:08:00 +0100149 union {
Tejun Heoa612fdd2011-12-14 00:33:41 +0100150 struct {
151 struct io_cq *icq;
152 void *priv[2];
153 } elv;
154
Mike Snitzerc1867942011-02-11 11:08:00 +0100155 struct {
156 unsigned int seq;
157 struct list_head list;
Jeff Moyer4853aba2011-08-15 21:37:25 +0200158 rq_end_io_fn *saved_end_io;
Mike Snitzerc1867942011-02-11 11:08:00 +0100159 } flush;
160 };
Jens Axboeff7d1452006-07-12 14:04:37 +0200161
Jens Axboe8f34ee72006-06-13 09:02:34 +0200162 struct gendisk *rq_disk;
Jerome Marchand09e099d2011-01-05 16:57:38 +0100163 struct hd_struct *part;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164 unsigned long start_time;
Divyesh Shah91952912010-04-01 15:01:41 -0700165#ifdef CONFIG_BLK_CGROUP
Tejun Heoa0516612012-06-26 15:05:44 -0700166 struct request_list *rl; /* rl this rq is alloced from */
Divyesh Shah91952912010-04-01 15:01:41 -0700167 unsigned long long start_time_ns;
168 unsigned long long io_start_time_ns; /* when passed to hardware */
169#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 /* Number of scatter-gather DMA addr+len pairs after
171 * physical address coalescing is performed.
172 */
173 unsigned short nr_phys_segments;
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200174#if defined(CONFIG_BLK_DEV_INTEGRITY)
175 unsigned short nr_integrity_segments;
176#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177
Jens Axboe8f34ee72006-06-13 09:02:34 +0200178 unsigned short ioprio;
179
Tejun Heo731ec492009-04-23 11:05:20 +0900180 void *special; /* opaque pointer available for LLD use */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181
Jens Axboecdd60262006-07-28 09:32:07 +0200182 int tag;
183 int errors;
184
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 /*
186 * when request is used as a packet command carrier
187 */
FUJITA Tomonorid7e3c322008-04-29 09:54:39 +0200188 unsigned char __cmd[BLK_MAX_CDB];
189 unsigned char *cmd;
Richard Kennedy181fdde2010-03-19 08:58:16 +0100190 unsigned short cmd_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100192 unsigned int extra_len; /* length of alignment and padding */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 unsigned int sense_len;
Tejun Heoc3a4d782009-05-07 22:24:37 +0900194 unsigned int resid_len; /* residual count */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195 void *sense;
196
Jens Axboe242f9dc2008-09-14 05:55:09 -0700197 unsigned long deadline;
198 struct list_head timeout_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700199 unsigned int timeout;
Mike Christie17e01f22005-11-11 05:31:37 -0600200 int retries;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201
202 /*
Jens Axboec00895a2006-09-30 20:29:12 +0200203 * completion callback.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 */
205 rq_end_io_fn *end_io;
206 void *end_io_data;
FUJITA Tomonoriabae1fd2007-07-16 08:52:14 +0200207
208 /* for bidi */
209 struct request *next_rq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210};
211
Fernando Luis Vázquez Cao766ca442008-08-14 09:59:13 +0200212static inline unsigned short req_get_ioprio(struct request *req)
213{
214 return req->ioprio;
215}
216
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217/*
Jens Axboe4aff5e22006-08-10 08:44:47 +0200218 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 * requests. Some step values could eventually be made generic.
220 */
221struct request_pm_state
222{
223 /* PM state machine step value, currently driver specific */
224 int pm_step;
225 /* requested PM state value (S1, S2, S3, S4, ...) */
226 u32 pm_state;
227 void* data; /* for driver use */
228};
229
230#include <linux/elevator.h>
231
Jens Axboe320ae512013-10-24 09:20:05 +0100232struct blk_queue_ctx;
233
Jens Axboe165125e2007-07-24 09:28:11 +0200234typedef void (request_fn_proc) (struct request_queue *q);
Christoph Hellwig5a7bbad2011-09-12 12:12:01 +0200235typedef void (make_request_fn) (struct request_queue *q, struct bio *bio);
Jens Axboe165125e2007-07-24 09:28:11 +0200236typedef int (prep_rq_fn) (struct request_queue *, struct request *);
James Bottomley28018c22010-07-01 19:49:17 +0900237typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238
239struct bio_vec;
Alasdair G Kergoncc371e62008-07-03 09:53:43 +0200240struct bvec_merge_data {
241 struct block_device *bi_bdev;
242 sector_t bi_sector;
243 unsigned bi_size;
244 unsigned long bi_rw;
245};
246typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *,
247 struct bio_vec *);
Jens Axboeff856ba2006-01-09 16:02:34 +0100248typedef void (softirq_done_fn)(struct request *);
Tejun Heo2fb98e82008-02-19 11:36:53 +0100249typedef int (dma_drain_needed_fn)(struct request *);
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +0200250typedef int (lld_busy_fn) (struct request_queue *q);
Mike Christieaa387cc2011-07-31 22:05:09 +0200251typedef int (bsg_job_fn) (struct bsg_job *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252
Jens Axboe242f9dc2008-09-14 05:55:09 -0700253enum blk_eh_timer_return {
254 BLK_EH_NOT_HANDLED,
255 BLK_EH_HANDLED,
256 BLK_EH_RESET_TIMER,
257};
258
259typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
260
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261enum blk_queue_state {
262 Queue_down,
263 Queue_up,
264};
265
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266struct blk_queue_tag {
267 struct request **tag_index; /* map of busy tags */
268 unsigned long *tag_map; /* bit map of free/busy tags */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 int busy; /* current depth */
270 int max_depth; /* what we will send to device */
Tejun Heoba025082005-08-05 13:28:11 -0700271 int real_max_depth; /* what the array can hold */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 atomic_t refcnt; /* map can be shared */
273};
274
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900275#define BLK_SCSI_MAX_CMDS (256)
276#define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
277
Martin K. Petersen025146e2009-05-22 17:17:51 -0400278struct queue_limits {
279 unsigned long bounce_pfn;
280 unsigned long seg_boundary_mask;
281
282 unsigned int max_hw_sectors;
Jens Axboe762380a2014-06-05 13:38:39 -0600283 unsigned int chunk_sectors;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400284 unsigned int max_sectors;
285 unsigned int max_segment_size;
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400286 unsigned int physical_block_size;
287 unsigned int alignment_offset;
288 unsigned int io_min;
289 unsigned int io_opt;
Christoph Hellwig67efc922009-09-30 13:54:20 +0200290 unsigned int max_discard_sectors;
Martin K. Petersen4363ac72012-09-18 12:19:27 -0400291 unsigned int max_write_same_sectors;
Martin K. Petersen86b37282009-11-10 11:50:21 +0100292 unsigned int discard_granularity;
293 unsigned int discard_alignment;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400294
295 unsigned short logical_block_size;
Martin K. Petersen8a783622010-02-26 00:20:39 -0500296 unsigned short max_segments;
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200297 unsigned short max_integrity_segments;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400298
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400299 unsigned char misaligned;
Martin K. Petersen86b37282009-11-10 11:50:21 +0100300 unsigned char discard_misaligned;
Martin K. Petersene692cb62010-12-01 19:41:49 +0100301 unsigned char cluster;
Martin K. Petersena934a002011-05-18 10:37:35 +0200302 unsigned char discard_zeroes_data;
Kent Overstreetc78afc62013-07-11 22:39:53 -0700303 unsigned char raid_partial_stripes_expensive;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400304};
305
Richard Kennedyd7b76302011-07-13 21:17:23 +0200306struct request_queue {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307 /*
308 * Together with queue_head for cacheline sharing
309 */
310 struct list_head queue_head;
311 struct request *last_merge;
Jens Axboeb374d182008-10-31 10:05:07 +0100312 struct elevator_queue *elevator;
Tejun Heo8a5ecdd2012-06-04 20:40:58 -0700313 int nr_rqs[2]; /* # allocated [a]sync rqs */
314 int nr_rqs_elvpriv; /* # allocated rqs w/ elvpriv */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315
316 /*
Tejun Heoa0516612012-06-26 15:05:44 -0700317 * If blkcg is not used, @q->root_rl serves all requests. If blkcg
318 * is used, root blkg allocates from @q->root_rl and all other
319 * blkgs from their own blkg->rl. Which one to use should be
320 * determined using bio_request_list().
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 */
Tejun Heoa0516612012-06-26 15:05:44 -0700322 struct request_list root_rl;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323
324 request_fn_proc *request_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 make_request_fn *make_request_fn;
326 prep_rq_fn *prep_rq_fn;
James Bottomley28018c22010-07-01 19:49:17 +0900327 unprep_rq_fn *unprep_rq_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 merge_bvec_fn *merge_bvec_fn;
Jens Axboeff856ba2006-01-09 16:02:34 +0100329 softirq_done_fn *softirq_done_fn;
Jens Axboe242f9dc2008-09-14 05:55:09 -0700330 rq_timed_out_fn *rq_timed_out_fn;
Tejun Heo2fb98e82008-02-19 11:36:53 +0100331 dma_drain_needed_fn *dma_drain_needed;
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +0200332 lld_busy_fn *lld_busy_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700333
Jens Axboe320ae512013-10-24 09:20:05 +0100334 struct blk_mq_ops *mq_ops;
335
336 unsigned int *mq_map;
337
338 /* sw queues */
Ming Leie6cdb092014-06-03 11:24:06 +0800339 struct blk_mq_ctx __percpu *queue_ctx;
Jens Axboe320ae512013-10-24 09:20:05 +0100340 unsigned int nr_queues;
341
342 /* hw dispatch queues */
343 struct blk_mq_hw_ctx **queue_hw_ctx;
344 unsigned int nr_hw_queues;
345
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346 /*
Tejun Heo8922e162005-10-20 16:23:44 +0200347 * Dispatch queue sorting
348 */
Jens Axboe1b47f532005-10-20 16:37:00 +0200349 sector_t end_sector;
Tejun Heo8922e162005-10-20 16:23:44 +0200350 struct request *boundary_rq;
Tejun Heo8922e162005-10-20 16:23:44 +0200351
352 /*
Jens Axboe3cca6dc2011-03-02 11:08:00 -0500353 * Delayed queue handling
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 */
Jens Axboe3cca6dc2011-03-02 11:08:00 -0500355 struct delayed_work delay_work;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356
357 struct backing_dev_info backing_dev_info;
358
359 /*
360 * The queue owner gets to use this for whatever they like.
361 * ll_rw_blk doesn't touch it.
362 */
363 void *queuedata;
364
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366 * various queue flags, see QUEUE_* below
367 */
368 unsigned long queue_flags;
369
370 /*
Tejun Heoa73f7302011-12-14 00:33:37 +0100371 * ida allocated id for this queue. Used to index queues from
372 * ioctx.
373 */
374 int id;
375
376 /*
Richard Kennedyd7b76302011-07-13 21:17:23 +0200377 * queue needs bounce pages for pages above this limit
378 */
379 gfp_t bounce_gfp;
380
381 /*
152587d2005-04-12 16:22:06 -0500382 * protects queue structures from reentrancy. ->__queue_lock should
383 * _never_ be used directly, it is queue private. always use
384 * ->queue_lock.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385 */
152587d2005-04-12 16:22:06 -0500386 spinlock_t __queue_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387 spinlock_t *queue_lock;
388
389 /*
390 * queue kobject
391 */
392 struct kobject kobj;
393
Jens Axboe320ae512013-10-24 09:20:05 +0100394 /*
395 * mq queue kobject
396 */
397 struct kobject mq_kobj;
398
Lin Ming6c954662013-03-23 11:42:26 +0800399#ifdef CONFIG_PM_RUNTIME
400 struct device *dev;
401 int rpm_status;
402 unsigned int nr_pending;
403#endif
404
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 /*
406 * queue settings
407 */
408 unsigned long nr_requests; /* Max # of requests */
409 unsigned int nr_congestion_on;
410 unsigned int nr_congestion_off;
411 unsigned int nr_batching;
412
James Bottomleyfa0ccd82008-01-10 11:30:36 -0600413 unsigned int dma_drain_size;
Richard Kennedyd7b76302011-07-13 21:17:23 +0200414 void *dma_drain_buffer;
Tejun Heoe3790c72008-03-04 11:18:17 +0100415 unsigned int dma_pad_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416 unsigned int dma_alignment;
417
418 struct blk_queue_tag *queue_tags;
Jens Axboe6eca9002007-10-25 10:14:47 +0200419 struct list_head tag_busy_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420
Tejun Heo15853af2005-11-10 08:52:05 +0100421 unsigned int nr_sorted;
Jens Axboe0a7ae2f2009-05-20 08:54:31 +0200422 unsigned int in_flight[2];
Bart Van Assche24faf6f2012-11-28 13:46:45 +0100423 /*
424 * Number of active block driver functions for which blk_drain_queue()
425 * must wait. Must be incremented around functions that unlock the
426 * queue_lock internally, e.g. scsi_request_fn().
427 */
428 unsigned int request_fn_active;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429
Jens Axboe242f9dc2008-09-14 05:55:09 -0700430 unsigned int rq_timeout;
431 struct timer_list timeout;
432 struct list_head timeout_list;
433
Tejun Heoa612fdd2011-12-14 00:33:41 +0100434 struct list_head icq_list;
Tejun Heo4eef3042012-03-05 13:15:18 -0800435#ifdef CONFIG_BLK_CGROUP
Tejun Heoa2b16932012-04-13 13:11:33 -0700436 DECLARE_BITMAP (blkcg_pols, BLKCG_MAX_POLS);
Tejun Heo3c798392012-04-16 13:57:25 -0700437 struct blkcg_gq *root_blkg;
Tejun Heo03aa2642012-03-05 13:15:19 -0800438 struct list_head blkg_list;
Tejun Heo4eef3042012-03-05 13:15:18 -0800439#endif
Tejun Heoa612fdd2011-12-14 00:33:41 +0100440
Martin K. Petersen025146e2009-05-22 17:17:51 -0400441 struct queue_limits limits;
442
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 /*
444 * sg stuff
445 */
446 unsigned int sg_timeout;
447 unsigned int sg_reserved_size;
Christoph Lameter19460892005-06-23 00:08:19 -0700448 int node;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700449#ifdef CONFIG_BLK_DEV_IO_TRACE
Jens Axboe2056a782006-03-23 20:00:26 +0100450 struct blk_trace *blk_trace;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700451#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 /*
Tejun Heo4913efe2010-09-03 11:56:16 +0200453 * for flush operations
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454 */
Tejun Heo4913efe2010-09-03 11:56:16 +0200455 unsigned int flush_flags;
shaohua.li@intel.comf3876932011-05-06 11:34:32 -0600456 unsigned int flush_not_queueable:1;
shaohua.li@intel.com3ac0cc42011-05-06 11:34:41 -0600457 unsigned int flush_queue_delayed:1;
Tejun Heoae1b1532011-01-25 12:43:54 +0100458 unsigned int flush_pending_idx:1;
459 unsigned int flush_running_idx:1;
460 unsigned long flush_pending_since;
461 struct list_head flush_queue[2];
462 struct list_head flush_data_in_flight;
Christoph Hellwig18741982014-02-10 09:29:00 -0700463 struct request *flush_rq;
464 spinlock_t mq_flush_lock;
Al Viro483f4af2006-03-18 18:34:37 -0500465
Christoph Hellwig6fca6a62014-05-28 08:08:02 -0600466 struct list_head requeue_list;
467 spinlock_t requeue_lock;
468 struct work_struct requeue_work;
469
Al Viro483f4af2006-03-18 18:34:37 -0500470 struct mutex sysfs_lock;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200471
Tejun Heod7325802012-03-05 13:14:58 -0800472 int bypass_depth;
473
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200474#if defined(CONFIG_BLK_DEV_BSG)
Mike Christieaa387cc2011-07-31 22:05:09 +0200475 bsg_job_fn *bsg_job_fn;
476 int bsg_job_size;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200477 struct bsg_class_device bsg_dev;
478#endif
Vivek Goyale43473b2010-09-15 17:06:35 -0400479
480#ifdef CONFIG_BLK_DEV_THROTTLING
481 /* Throttle data */
482 struct throtl_data *td;
483#endif
Tejun Heo548bc8e2013-01-09 08:05:13 -0800484 struct rcu_head rcu_head;
Jens Axboe320ae512013-10-24 09:20:05 +0100485 wait_queue_head_t mq_freeze_wq;
486 struct percpu_counter mq_usage_counter;
487 struct list_head all_q_node;
Jens Axboe0d2602c2014-05-13 15:10:52 -0600488
489 struct blk_mq_tag_set *tag_set;
490 struct list_head tag_set_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491};
492
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493#define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
494#define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
Jens Axboe1faa16d2009-04-06 14:48:01 +0200495#define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
496#define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
Bart Van Assche3f3299d2012-11-28 13:42:38 +0100497#define QUEUE_FLAG_DYING 5 /* queue being torn down */
Tejun Heod7325802012-03-05 13:14:58 -0800498#define QUEUE_FLAG_BYPASS 6 /* act as dumb FIFO queue */
Jens Axboec21e6be2011-04-19 13:32:46 +0200499#define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
500#define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
Dan Williams5757a6d2011-07-23 20:44:25 +0200501#define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
Jens Axboec21e6be2011-04-19 13:32:46 +0200502#define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
503#define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
504#define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
Fernando Luis Vázquez Cao88e740f2008-10-27 18:44:46 +0900505#define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
Jens Axboec21e6be2011-04-19 13:32:46 +0200506#define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
507#define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
508#define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
509#define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
510#define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
Dan Williams5757a6d2011-07-23 20:44:25 +0200511#define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
Bart Van Asschec246e802012-12-06 14:32:01 +0100512#define QUEUE_FLAG_DEAD 19 /* queue tear-down finished */
Jens Axboe320ae512013-10-24 09:20:05 +0100513#define QUEUE_FLAG_INIT_DONE 20 /* queue is initialized */
Jens Axboe05f1dd52014-05-29 09:53:32 -0600514#define QUEUE_FLAG_NO_SG_MERGE 21 /* don't attempt to merge SG segments*/
Jens Axboe66cb45a2014-06-24 16:22:24 -0600515#define QUEUE_FLAG_SG_GAPS 22 /* queue doesn't support SG gaps */
Jens Axboebc58ba92009-01-23 10:54:44 +0100516
517#define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
Jens Axboe01e97f62009-09-03 20:06:47 +0200518 (1 << QUEUE_FLAG_STACKABLE) | \
Jens Axboee2e1a142010-06-09 10:42:09 +0200519 (1 << QUEUE_FLAG_SAME_COMP) | \
520 (1 << QUEUE_FLAG_ADD_RANDOM))
Tejun Heo797e7db2006-01-06 09:51:03 +0100521
Jens Axboe94eddfb2013-11-19 09:25:07 -0700522#define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
523 (1 << QUEUE_FLAG_SAME_COMP))
524
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200525static inline void queue_lockdep_assert_held(struct request_queue *q)
Linus Torvalds8f45c1a2008-04-29 10:16:38 -0700526{
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200527 if (q->queue_lock)
528 lockdep_assert_held(q->queue_lock);
Linus Torvalds8f45c1a2008-04-29 10:16:38 -0700529}
530
Nick Piggin75ad23b2008-04-29 14:48:33 +0200531static inline void queue_flag_set_unlocked(unsigned int flag,
532 struct request_queue *q)
533{
534 __set_bit(flag, &q->queue_flags);
535}
536
Jens Axboee48ec692008-07-03 13:18:54 +0200537static inline int queue_flag_test_and_clear(unsigned int flag,
538 struct request_queue *q)
539{
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200540 queue_lockdep_assert_held(q);
Jens Axboee48ec692008-07-03 13:18:54 +0200541
542 if (test_bit(flag, &q->queue_flags)) {
543 __clear_bit(flag, &q->queue_flags);
544 return 1;
545 }
546
547 return 0;
548}
549
550static inline int queue_flag_test_and_set(unsigned int flag,
551 struct request_queue *q)
552{
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200553 queue_lockdep_assert_held(q);
Jens Axboee48ec692008-07-03 13:18:54 +0200554
555 if (!test_bit(flag, &q->queue_flags)) {
556 __set_bit(flag, &q->queue_flags);
557 return 0;
558 }
559
560 return 1;
561}
562
Nick Piggin75ad23b2008-04-29 14:48:33 +0200563static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
564{
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200565 queue_lockdep_assert_held(q);
Nick Piggin75ad23b2008-04-29 14:48:33 +0200566 __set_bit(flag, &q->queue_flags);
567}
568
569static inline void queue_flag_clear_unlocked(unsigned int flag,
570 struct request_queue *q)
571{
572 __clear_bit(flag, &q->queue_flags);
573}
574
Jens Axboe0a7ae2f2009-05-20 08:54:31 +0200575static inline int queue_in_flight(struct request_queue *q)
576{
577 return q->in_flight[0] + q->in_flight[1];
578}
579
Nick Piggin75ad23b2008-04-29 14:48:33 +0200580static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
581{
Andi Kleen8bcb6c72012-03-30 12:33:28 +0200582 queue_lockdep_assert_held(q);
Nick Piggin75ad23b2008-04-29 14:48:33 +0200583 __clear_bit(flag, &q->queue_flags);
584}
585
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586#define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
587#define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
Bart Van Assche3f3299d2012-11-28 13:42:38 +0100588#define blk_queue_dying(q) test_bit(QUEUE_FLAG_DYING, &(q)->queue_flags)
Bart Van Asschec246e802012-12-06 14:32:01 +0100589#define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
Tejun Heod7325802012-03-05 13:14:58 -0800590#define blk_queue_bypass(q) test_bit(QUEUE_FLAG_BYPASS, &(q)->queue_flags)
Jens Axboe320ae512013-10-24 09:20:05 +0100591#define blk_queue_init_done(q) test_bit(QUEUE_FLAG_INIT_DONE, &(q)->queue_flags)
Alan D. Brunelleac9fafa2008-04-29 14:44:19 +0200592#define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
Alan D. Brunelle488991e2010-01-29 09:04:08 +0100593#define blk_queue_noxmerges(q) \
594 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
Jens Axboea68bbdd2008-09-24 13:03:33 +0200595#define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
Jens Axboebc58ba92009-01-23 10:54:44 +0100596#define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
Jens Axboee2e1a142010-06-09 10:42:09 +0200597#define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
Kiyoshi Ueda4ee5eaf2008-09-18 10:46:13 -0400598#define blk_queue_stackable(q) \
599 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
Christoph Hellwigc15227d2009-09-30 13:52:12 +0200600#define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
Adrian Hunter8d57a982010-08-11 14:17:49 -0700601#define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
602 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603
Christoph Hellwig33659eb2010-08-07 18:17:56 +0200604#define blk_noretry_request(rq) \
605 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
606 REQ_FAILFAST_DRIVER))
Jens Axboe4aff5e22006-08-10 08:44:47 +0200607
Christoph Hellwig33659eb2010-08-07 18:17:56 +0200608#define blk_account_rq(rq) \
609 (((rq)->cmd_flags & REQ_STARTED) && \
Martin K. Petersene2a60da2012-09-18 12:19:25 -0400610 ((rq)->cmd_type == REQ_TYPE_FS))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612#define blk_pm_request(rq) \
Christoph Hellwig33659eb2010-08-07 18:17:56 +0200613 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
614 (rq)->cmd_type == REQ_TYPE_PM_RESUME)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615
Jens Axboeab780f12008-08-26 10:25:02 +0200616#define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
FUJITA Tomonoriabae1fd2007-07-16 08:52:14 +0200617#define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
Kiyoshi Ueda336cdb42007-12-11 17:40:30 -0500618/* rq->queuelist of dequeued request must be list_empty() */
619#define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620
621#define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
622
Jens Axboe59533162013-05-23 12:25:08 +0200623#define rq_data_dir(rq) (((rq)->cmd_flags & 1) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624
Jens Axboe49fd5242014-04-16 10:57:18 -0600625/*
626 * Driver can handle struct request, if it either has an old style
627 * request_fn defined, or is blk-mq based.
628 */
629static inline bool queue_is_rq_based(struct request_queue *q)
630{
631 return q->request_fn || q->mq_ops;
632}
633
Martin K. Petersene692cb62010-12-01 19:41:49 +0100634static inline unsigned int blk_queue_cluster(struct request_queue *q)
635{
636 return q->limits.cluster;
637}
638
Jens Axboe9e2585a2006-07-28 09:26:13 +0200639/*
Jens Axboe1faa16d2009-04-06 14:48:01 +0200640 * We regard a request as sync, if either a read or a sync write
Jens Axboe9e2585a2006-07-28 09:26:13 +0200641 */
Jens Axboe1faa16d2009-04-06 14:48:01 +0200642static inline bool rw_is_sync(unsigned int rw_flags)
643{
Christoph Hellwig7b6d91d2010-08-07 18:20:39 +0200644 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
Jens Axboe1faa16d2009-04-06 14:48:01 +0200645}
646
647static inline bool rq_is_sync(struct request *rq)
648{
649 return rw_is_sync(rq->cmd_flags);
650}
651
Tejun Heo5b788ce2012-06-04 20:40:59 -0700652static inline bool blk_rl_full(struct request_list *rl, bool sync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653{
Tejun Heo5b788ce2012-06-04 20:40:59 -0700654 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
655
656 return rl->flags & flag;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657}
658
Tejun Heo5b788ce2012-06-04 20:40:59 -0700659static inline void blk_set_rl_full(struct request_list *rl, bool sync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660{
Tejun Heo5b788ce2012-06-04 20:40:59 -0700661 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
662
663 rl->flags |= flag;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664}
665
Tejun Heo5b788ce2012-06-04 20:40:59 -0700666static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667{
Tejun Heo5b788ce2012-06-04 20:40:59 -0700668 unsigned int flag = sync ? BLK_RL_SYNCFULL : BLK_RL_ASYNCFULL;
669
670 rl->flags &= ~flag;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671}
672
Martin K. Petersene2a60da2012-09-18 12:19:25 -0400673static inline bool rq_mergeable(struct request *rq)
674{
675 if (rq->cmd_type != REQ_TYPE_FS)
676 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700677
Martin K. Petersene2a60da2012-09-18 12:19:25 -0400678 if (rq->cmd_flags & REQ_NOMERGE_FLAGS)
679 return false;
680
681 return true;
682}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400684static inline bool blk_check_merge_flags(unsigned int flags1,
685 unsigned int flags2)
686{
687 if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD))
688 return false;
689
690 if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE))
691 return false;
692
Martin K. Petersen4363ac72012-09-18 12:19:27 -0400693 if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME))
694 return false;
695
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400696 return true;
697}
698
Martin K. Petersen4363ac72012-09-18 12:19:27 -0400699static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b)
700{
701 if (bio_data(a) == bio_data(b))
702 return true;
703
704 return false;
705}
706
Linus Torvalds1da177e2005-04-16 15:20:36 -0700707/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700708 * q->prep_rq_fn return values
709 */
710#define BLKPREP_OK 0 /* serve it */
711#define BLKPREP_KILL 1 /* fatal error, kill */
712#define BLKPREP_DEFER 2 /* leave on queue */
713
714extern unsigned long blk_max_low_pfn, blk_max_pfn;
715
716/*
717 * standard bounce addresses:
718 *
719 * BLK_BOUNCE_HIGH : bounce all highmem pages
720 * BLK_BOUNCE_ANY : don't bounce anything
721 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
722 */
Andi Kleen24728922008-04-21 09:51:05 +0200723
724#if BITS_PER_LONG == 32
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725#define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
Andi Kleen24728922008-04-21 09:51:05 +0200726#else
727#define BLK_BOUNCE_HIGH -1ULL
728#endif
729#define BLK_BOUNCE_ANY (-1ULL)
FUJITA Tomonoribfe17232010-05-31 15:59:03 +0900730#define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731
Jens Axboe3d6392c2007-07-09 12:38:05 +0200732/*
733 * default timeout for SG_IO if none specified
734 */
735#define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
Linus Torvaldsf2f1fa72008-12-05 14:49:18 -0800736#define BLK_MIN_SG_TIMEOUT (7 * HZ)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200737
Christoph Lameter2a7326b2007-07-17 04:03:37 -0700738#ifdef CONFIG_BOUNCE
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739extern int init_emergency_isa_pool(void);
Jens Axboe165125e2007-07-24 09:28:11 +0200740extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741#else
742static inline int init_emergency_isa_pool(void)
743{
744 return 0;
745}
Jens Axboe165125e2007-07-24 09:28:11 +0200746static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747{
748}
749#endif /* CONFIG_MMU */
750
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900751struct rq_map_data {
752 struct page **pages;
753 int page_order;
754 int nr_entries;
FUJITA Tomonori56c451f2008-12-18 14:49:37 +0900755 unsigned long offset;
FUJITA Tomonori97ae77a2008-12-18 14:49:38 +0900756 int null_mapped;
FUJITA Tomonoriecb554a2009-07-09 14:46:53 +0200757 int from_user;
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900758};
759
NeilBrown5705f702007-09-25 12:35:59 +0200760struct req_iterator {
Kent Overstreet79886132013-11-23 17:19:00 -0800761 struct bvec_iter iter;
NeilBrown5705f702007-09-25 12:35:59 +0200762 struct bio *bio;
763};
764
765/* This should not be used directly - use rq_for_each_segment */
Jens Axboe1e428072009-02-23 09:03:10 +0100766#define for_each_bio(_bio) \
767 for (; _bio; _bio = _bio->bi_next)
NeilBrown5705f702007-09-25 12:35:59 +0200768#define __rq_for_each_bio(_bio, rq) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769 if ((rq->bio)) \
770 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
771
NeilBrown5705f702007-09-25 12:35:59 +0200772#define rq_for_each_segment(bvl, _rq, _iter) \
773 __rq_for_each_bio(_iter.bio, _rq) \
Kent Overstreet79886132013-11-23 17:19:00 -0800774 bio_for_each_segment(bvl, _iter.bio, _iter.iter)
NeilBrown5705f702007-09-25 12:35:59 +0200775
Kent Overstreet4550dd62013-08-07 14:26:21 -0700776#define rq_iter_last(bvec, _iter) \
Kent Overstreet79886132013-11-23 17:19:00 -0800777 (_iter.bio->bi_next == NULL && \
Kent Overstreet4550dd62013-08-07 14:26:21 -0700778 bio_iter_last(bvec, _iter.iter))
NeilBrown5705f702007-09-25 12:35:59 +0200779
Ilya Loginov2d4dc892009-11-26 09:16:19 +0100780#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
781# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
782#endif
783#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
784extern void rq_flush_dcache_pages(struct request *rq);
785#else
786static inline void rq_flush_dcache_pages(struct request *rq)
787{
788}
789#endif
790
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791extern int blk_register_queue(struct gendisk *disk);
792extern void blk_unregister_queue(struct gendisk *disk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793extern void generic_make_request(struct bio *bio);
FUJITA Tomonori2a4aa302008-04-29 09:54:36 +0200794extern void blk_rq_init(struct request_queue *q, struct request *rq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795extern void blk_put_request(struct request *);
Jens Axboe165125e2007-07-24 09:28:11 +0200796extern void __blk_put_request(struct request_queue *, struct request *);
Jens Axboe165125e2007-07-24 09:28:11 +0200797extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
Boaz Harrosh79eb63e2009-05-17 18:57:15 +0300798extern struct request *blk_make_request(struct request_queue *, struct bio *,
799 gfp_t);
Jens Axboef27b0872014-06-06 07:57:37 -0600800extern void blk_rq_set_block_pc(struct request *);
Jens Axboe165125e2007-07-24 09:28:11 +0200801extern void blk_requeue_request(struct request_queue *, struct request *);
Christoph Hellwig66ac0282010-06-18 16:59:42 +0200802extern void blk_add_request_payload(struct request *rq, struct page *page,
803 unsigned int len);
Kiyoshi Ueda82124d62008-09-18 10:45:38 -0400804extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +0200805extern int blk_lld_busy(struct request_queue *q);
Kiyoshi Uedab0fd2712009-06-11 13:10:16 +0200806extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
807 struct bio_set *bs, gfp_t gfp_mask,
808 int (*bio_ctr)(struct bio *, struct bio *, void *),
809 void *data);
810extern void blk_rq_unprep_clone(struct request *rq);
Kiyoshi Ueda82124d62008-09-18 10:45:38 -0400811extern int blk_insert_cloned_request(struct request_queue *q,
812 struct request *rq);
Jens Axboe3cca6dc2011-03-02 11:08:00 -0500813extern void blk_delay_queue(struct request_queue *, unsigned long);
Jens Axboe165125e2007-07-24 09:28:11 +0200814extern void blk_recount_segments(struct request_queue *, struct bio *);
Paolo Bonzini0bfc96c2012-01-12 16:01:28 +0100815extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
Paolo Bonzini577ebb32012-01-12 16:01:27 +0100816extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
817 unsigned int, void __user *);
Al Viro74f3c8a2007-08-27 15:38:10 -0400818extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
819 unsigned int, void __user *);
Al Viroe915e872008-09-02 17:16:41 -0400820extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
821 struct scsi_ioctl_command __user *);
Andrew Morton3fcfab12006-10-19 23:28:16 -0700822
Christoph Hellwig5a7bbad2011-09-12 12:12:01 +0200823extern void blk_queue_bio(struct request_queue *q, struct bio *bio);
Christoph Hellwig166e1f92011-09-12 12:08:27 +0200824
Andrew Morton3fcfab12006-10-19 23:28:16 -0700825/*
826 * A queue has just exitted congestion. Note this in the global counter of
827 * congested queues, and wake up anyone who was waiting for requests to be
828 * put back.
829 */
Jens Axboe8aa7e842009-07-09 14:52:32 +0200830static inline void blk_clear_queue_congested(struct request_queue *q, int sync)
Andrew Morton3fcfab12006-10-19 23:28:16 -0700831{
Jens Axboe8aa7e842009-07-09 14:52:32 +0200832 clear_bdi_congested(&q->backing_dev_info, sync);
Andrew Morton3fcfab12006-10-19 23:28:16 -0700833}
834
835/*
836 * A queue has just entered congestion. Flag that in the queue's VM-visible
837 * state flags and increment the global gounter of congested queues.
838 */
Jens Axboe8aa7e842009-07-09 14:52:32 +0200839static inline void blk_set_queue_congested(struct request_queue *q, int sync)
Andrew Morton3fcfab12006-10-19 23:28:16 -0700840{
Jens Axboe8aa7e842009-07-09 14:52:32 +0200841 set_bdi_congested(&q->backing_dev_info, sync);
Andrew Morton3fcfab12006-10-19 23:28:16 -0700842}
843
Jens Axboe165125e2007-07-24 09:28:11 +0200844extern void blk_start_queue(struct request_queue *q);
845extern void blk_stop_queue(struct request_queue *q);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846extern void blk_sync_queue(struct request_queue *q);
Jens Axboe165125e2007-07-24 09:28:11 +0200847extern void __blk_stop_queue(struct request_queue *q);
Christoph Hellwig24ecfbe2011-04-18 11:41:33 +0200848extern void __blk_run_queue(struct request_queue *q);
Jens Axboe165125e2007-07-24 09:28:11 +0200849extern void blk_run_queue(struct request_queue *);
Jens Axboec21e6be2011-04-19 13:32:46 +0200850extern void blk_run_queue_async(struct request_queue *q);
FUJITA Tomonoria3bce902008-08-28 16:17:05 +0900851extern int blk_rq_map_user(struct request_queue *, struct request *,
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900852 struct rq_map_data *, void __user *, unsigned long,
853 gfp_t);
Jens Axboe8e5cfc42006-12-19 11:12:46 +0100854extern int blk_rq_unmap_user(struct bio *);
Jens Axboe165125e2007-07-24 09:28:11 +0200855extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
856extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
Al Viro86d564c2014-02-08 20:42:52 -0500857 struct rq_map_data *, const struct sg_iovec *,
858 int, unsigned int, gfp_t);
Jens Axboe165125e2007-07-24 09:28:11 +0200859extern int blk_execute_rq(struct request_queue *, struct gendisk *,
James Bottomley 994ca9a2005-06-20 14:11:09 +0200860 struct request *, int);
Jens Axboe165125e2007-07-24 09:28:11 +0200861extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
Jens Axboe15fc8582006-01-06 10:00:50 +0100862 struct request *, int, rq_end_io_fn *);
Mike Christie6e39b69e2005-11-11 05:30:24 -0600863
Jens Axboe165125e2007-07-24 09:28:11 +0200864static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865{
866 return bdev->bd_disk->queue;
867}
868
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869/*
Tejun Heo80a761f2009-07-03 17:48:17 +0900870 * blk_rq_pos() : the current sector
871 * blk_rq_bytes() : bytes left in the entire request
872 * blk_rq_cur_bytes() : bytes left in the current segment
873 * blk_rq_err_bytes() : bytes left till the next error boundary
874 * blk_rq_sectors() : sectors left in the entire request
875 * blk_rq_cur_sectors() : sectors left in the current segment
Tejun Heo5efccd12009-04-23 11:05:18 +0900876 */
Tejun Heo5b936292009-05-07 22:24:38 +0900877static inline sector_t blk_rq_pos(const struct request *rq)
878{
Tejun Heoa2dec7b2009-05-07 22:24:44 +0900879 return rq->__sector;
Tejun Heo5b936292009-05-07 22:24:38 +0900880}
881
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900882static inline unsigned int blk_rq_bytes(const struct request *rq)
883{
Tejun Heoa2dec7b2009-05-07 22:24:44 +0900884 return rq->__data_len;
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900885}
886
887static inline int blk_rq_cur_bytes(const struct request *rq)
888{
889 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
890}
Tejun Heo5efccd12009-04-23 11:05:18 +0900891
Tejun Heo80a761f2009-07-03 17:48:17 +0900892extern unsigned int blk_rq_err_bytes(const struct request *rq);
893
Tejun Heo5b936292009-05-07 22:24:38 +0900894static inline unsigned int blk_rq_sectors(const struct request *rq)
895{
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900896 return blk_rq_bytes(rq) >> 9;
Tejun Heo5b936292009-05-07 22:24:38 +0900897}
898
899static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
900{
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900901 return blk_rq_cur_bytes(rq) >> 9;
Tejun Heo5b936292009-05-07 22:24:38 +0900902}
903
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400904static inline unsigned int blk_queue_get_max_sectors(struct request_queue *q,
905 unsigned int cmd_flags)
906{
907 if (unlikely(cmd_flags & REQ_DISCARD))
James Bottomley871dd922013-04-24 08:52:50 -0600908 return min(q->limits.max_discard_sectors, UINT_MAX >> 9);
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400909
Martin K. Petersen4363ac72012-09-18 12:19:27 -0400910 if (unlikely(cmd_flags & REQ_WRITE_SAME))
911 return q->limits.max_write_same_sectors;
912
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400913 return q->limits.max_sectors;
914}
915
Jens Axboe762380a2014-06-05 13:38:39 -0600916/*
917 * Return maximum size of a request at given offset. Only valid for
918 * file system requests.
919 */
920static inline unsigned int blk_max_size_offset(struct request_queue *q,
921 sector_t offset)
922{
923 if (!q->limits.chunk_sectors)
Jens Axboe736ed4d2014-06-17 22:09:29 -0700924 return q->limits.max_sectors;
Jens Axboe762380a2014-06-05 13:38:39 -0600925
926 return q->limits.chunk_sectors -
927 (offset & (q->limits.chunk_sectors - 1));
928}
929
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400930static inline unsigned int blk_rq_get_max_sectors(struct request *rq)
931{
932 struct request_queue *q = rq->q;
933
934 if (unlikely(rq->cmd_type == REQ_TYPE_BLOCK_PC))
935 return q->limits.max_hw_sectors;
936
Jens Axboe762380a2014-06-05 13:38:39 -0600937 if (!q->limits.chunk_sectors)
938 return blk_queue_get_max_sectors(q, rq->cmd_flags);
939
940 return min(blk_max_size_offset(q, blk_rq_pos(rq)),
941 blk_queue_get_max_sectors(q, rq->cmd_flags));
Martin K. Petersenf31dc1c2012-09-18 12:19:26 -0400942}
943
Jun'ichi Nomura75afb352013-09-21 13:57:47 -0600944static inline unsigned int blk_rq_count_bios(struct request *rq)
945{
946 unsigned int nr_bios = 0;
947 struct bio *bio;
948
949 __rq_for_each_bio(bio, rq)
950 nr_bios++;
951
952 return nr_bios;
953}
954
Tejun Heo5efccd12009-04-23 11:05:18 +0900955/*
Tejun Heo9934c8c2009-05-08 11:54:16 +0900956 * Request issue related functions.
957 */
958extern struct request *blk_peek_request(struct request_queue *q);
959extern void blk_start_request(struct request *rq);
960extern struct request *blk_fetch_request(struct request_queue *q);
961
962/*
Tejun Heo2e60e022009-04-23 11:05:18 +0900963 * Request completion related functions.
964 *
965 * blk_update_request() completes given number of bytes and updates
966 * the request without completing it.
967 *
Tejun Heof06d9a22009-04-23 11:05:19 +0900968 * blk_end_request() and friends. __blk_end_request() must be called
969 * with the request queue spinlock acquired.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970 *
971 * Several drivers define their own end_request and call
Kiyoshi Ueda3bcddea2007-12-11 17:52:28 -0500972 * blk_end_request() for parts of the original function.
973 * This prevents code duplication in drivers.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974 */
Tejun Heo2e60e022009-04-23 11:05:18 +0900975extern bool blk_update_request(struct request *rq, int error,
976 unsigned int nr_bytes);
Christoph Hellwig12120072014-04-16 09:44:59 +0200977extern void blk_finish_request(struct request *rq, int error);
FUJITA Tomonorib1f74492009-05-11 17:56:09 +0900978extern bool blk_end_request(struct request *rq, int error,
979 unsigned int nr_bytes);
980extern void blk_end_request_all(struct request *rq, int error);
981extern bool blk_end_request_cur(struct request *rq, int error);
Tejun Heo80a761f2009-07-03 17:48:17 +0900982extern bool blk_end_request_err(struct request *rq, int error);
FUJITA Tomonorib1f74492009-05-11 17:56:09 +0900983extern bool __blk_end_request(struct request *rq, int error,
984 unsigned int nr_bytes);
985extern void __blk_end_request_all(struct request *rq, int error);
986extern bool __blk_end_request_cur(struct request *rq, int error);
Tejun Heo80a761f2009-07-03 17:48:17 +0900987extern bool __blk_end_request_err(struct request *rq, int error);
Tejun Heo2e60e022009-04-23 11:05:18 +0900988
Jens Axboeff856ba2006-01-09 16:02:34 +0100989extern void blk_complete_request(struct request *);
Jens Axboe242f9dc2008-09-14 05:55:09 -0700990extern void __blk_complete_request(struct request *);
991extern void blk_abort_request(struct request *);
James Bottomley28018c22010-07-01 19:49:17 +0900992extern void blk_unprep_request(struct request *);
Jens Axboeff856ba2006-01-09 16:02:34 +0100993
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 * Access functions for manipulating queue properties
996 */
Jens Axboe165125e2007-07-24 09:28:11 +0200997extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
Christoph Lameter19460892005-06-23 00:08:19 -0700998 spinlock_t *lock, int node_id);
Jens Axboe165125e2007-07-24 09:28:11 +0200999extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
Mike Snitzer01effb02010-05-11 08:57:42 +02001000extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
1001 request_fn_proc *, spinlock_t *);
Jens Axboe165125e2007-07-24 09:28:11 +02001002extern void blk_cleanup_queue(struct request_queue *);
1003extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
1004extern void blk_queue_bounce_limit(struct request_queue *, u64);
Mike Snitzer72d4cd92010-12-17 08:34:20 +01001005extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int);
Martin K. Petersen086fa5f2010-02-26 00:20:38 -05001006extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
Jens Axboe762380a2014-06-05 13:38:39 -06001007extern void blk_queue_chunk_sectors(struct request_queue *, unsigned int);
Martin K. Petersen8a783622010-02-26 00:20:39 -05001008extern void blk_queue_max_segments(struct request_queue *, unsigned short);
Jens Axboe165125e2007-07-24 09:28:11 +02001009extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
Christoph Hellwig67efc922009-09-30 13:54:20 +02001010extern void blk_queue_max_discard_sectors(struct request_queue *q,
1011 unsigned int max_discard_sectors);
Martin K. Petersen4363ac72012-09-18 12:19:27 -04001012extern void blk_queue_max_write_same_sectors(struct request_queue *q,
1013 unsigned int max_write_same_sectors);
Martin K. Petersene1defc42009-05-22 17:17:49 -04001014extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
Martin K. Petersen892b6f92010-10-13 21:18:03 +02001015extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001016extern void blk_queue_alignment_offset(struct request_queue *q,
1017 unsigned int alignment);
Martin K. Petersen7c958e32009-07-31 11:49:11 -04001018extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001019extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
Martin K. Petersen3c5820c2009-09-11 21:54:52 +02001020extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001021extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
Martin K. Petersene475bba2009-06-16 08:23:52 +02001022extern void blk_set_default_limits(struct queue_limits *lim);
Martin K. Petersenb1bd0552012-01-11 16:27:11 +01001023extern void blk_set_stacking_limits(struct queue_limits *lim);
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001024extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
1025 sector_t offset);
Martin K. Petersen17be8c22010-01-11 03:21:49 -05001026extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
1027 sector_t offset);
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001028extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
1029 sector_t offset);
Jens Axboe165125e2007-07-24 09:28:11 +02001030extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
Tejun Heoe3790c72008-03-04 11:18:17 +01001031extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
FUJITA Tomonori27f82212008-07-04 09:30:03 +02001032extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
Tejun Heo2fb98e82008-02-19 11:36:53 +01001033extern int blk_queue_dma_drain(struct request_queue *q,
1034 dma_drain_needed_fn *dma_drain_needed,
1035 void *buf, unsigned int size);
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +02001036extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
Jens Axboe165125e2007-07-24 09:28:11 +02001037extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
1038extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
James Bottomley28018c22010-07-01 19:49:17 +09001039extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
Jens Axboe165125e2007-07-24 09:28:11 +02001040extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *);
1041extern void blk_queue_dma_alignment(struct request_queue *, int);
James Bottomley11c3e682007-12-31 16:37:00 -06001042extern void blk_queue_update_dma_alignment(struct request_queue *, int);
Jens Axboe165125e2007-07-24 09:28:11 +02001043extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
Jens Axboe242f9dc2008-09-14 05:55:09 -07001044extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
1045extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
Tejun Heo4913efe2010-09-03 11:56:16 +02001046extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
shaohua.li@intel.comf3876932011-05-06 11:34:32 -06001047extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001048extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049
Jens Axboe165125e2007-07-24 09:28:11 +02001050extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
Asias He85b9f662012-08-02 23:42:04 +02001051extern int blk_bio_map_sg(struct request_queue *q, struct bio *bio,
1052 struct scatterlist *sglist);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053extern void blk_dump_rq_flags(struct request *, char *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001054extern long nr_blockdev_pages(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001055
Tejun Heo09ac46c2011-12-14 00:33:38 +01001056bool __must_check blk_get_queue(struct request_queue *);
Jens Axboe165125e2007-07-24 09:28:11 +02001057struct request_queue *blk_alloc_queue(gfp_t);
1058struct request_queue *blk_alloc_queue_node(gfp_t, int);
1059extern void blk_put_queue(struct request_queue *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060
Shaohua Li316cc672011-07-08 08:19:21 +02001061/*
Lin Ming6c954662013-03-23 11:42:26 +08001062 * block layer runtime pm functions
1063 */
1064#ifdef CONFIG_PM_RUNTIME
1065extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
1066extern int blk_pre_runtime_suspend(struct request_queue *q);
1067extern void blk_post_runtime_suspend(struct request_queue *q, int err);
1068extern void blk_pre_runtime_resume(struct request_queue *q);
1069extern void blk_post_runtime_resume(struct request_queue *q, int err);
1070#else
1071static inline void blk_pm_runtime_init(struct request_queue *q,
1072 struct device *dev) {}
1073static inline int blk_pre_runtime_suspend(struct request_queue *q)
1074{
1075 return -ENOSYS;
1076}
1077static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
1078static inline void blk_pre_runtime_resume(struct request_queue *q) {}
1079static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
1080#endif
1081
1082/*
Suresh Jayaraman75df7132011-09-21 10:00:16 +02001083 * blk_plug permits building a queue of related requests by holding the I/O
1084 * fragments for a short period. This allows merging of sequential requests
1085 * into single larger request. As the requests are moved from a per-task list to
1086 * the device's request_queue in a batch, this results in improved scalability
1087 * as the lock contention for request_queue lock is reduced.
1088 *
1089 * It is ok not to disable preemption when adding the request to the plug list
1090 * or when attempting a merge, because blk_schedule_flush_list() will only flush
1091 * the plug list when the task sleeps by itself. For details, please see
1092 * schedule() where blk_schedule_flush_plug() is called.
Shaohua Li316cc672011-07-08 08:19:21 +02001093 */
Jens Axboe73c10102011-03-08 13:19:51 +01001094struct blk_plug {
Suresh Jayaraman75df7132011-09-21 10:00:16 +02001095 struct list_head list; /* requests */
Jens Axboe320ae512013-10-24 09:20:05 +01001096 struct list_head mq_list; /* blk-mq requests */
Suresh Jayaraman75df7132011-09-21 10:00:16 +02001097 struct list_head cb_list; /* md requires an unplug callback */
Jens Axboe73c10102011-03-08 13:19:51 +01001098};
Shaohua Li55c022b2011-07-08 08:19:20 +02001099#define BLK_MAX_REQUEST_COUNT 16
1100
NeilBrown9cbb1752012-07-31 09:08:14 +02001101struct blk_plug_cb;
NeilBrown74018dc2012-07-31 09:08:15 +02001102typedef void (*blk_plug_cb_fn)(struct blk_plug_cb *, bool);
NeilBrown048c9372011-04-18 09:52:22 +02001103struct blk_plug_cb {
1104 struct list_head list;
NeilBrown9cbb1752012-07-31 09:08:14 +02001105 blk_plug_cb_fn callback;
1106 void *data;
NeilBrown048c9372011-04-18 09:52:22 +02001107};
NeilBrown9cbb1752012-07-31 09:08:14 +02001108extern struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug,
1109 void *data, int size);
Jens Axboe73c10102011-03-08 13:19:51 +01001110extern void blk_start_plug(struct blk_plug *);
1111extern void blk_finish_plug(struct blk_plug *);
Jens Axboef6603782011-04-15 15:49:07 +02001112extern void blk_flush_plug_list(struct blk_plug *, bool);
Jens Axboe73c10102011-03-08 13:19:51 +01001113
1114static inline void blk_flush_plug(struct task_struct *tsk)
1115{
1116 struct blk_plug *plug = tsk->plug;
1117
Christoph Hellwig88b996c2011-04-15 15:20:10 +02001118 if (plug)
Jens Axboea237c1c2011-04-16 13:27:55 +02001119 blk_flush_plug_list(plug, false);
1120}
1121
1122static inline void blk_schedule_flush_plug(struct task_struct *tsk)
1123{
1124 struct blk_plug *plug = tsk->plug;
1125
1126 if (plug)
Jens Axboef6603782011-04-15 15:49:07 +02001127 blk_flush_plug_list(plug, true);
Jens Axboe73c10102011-03-08 13:19:51 +01001128}
1129
1130static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1131{
1132 struct blk_plug *plug = tsk->plug;
1133
Jens Axboe320ae512013-10-24 09:20:05 +01001134 return plug &&
1135 (!list_empty(&plug->list) ||
1136 !list_empty(&plug->mq_list) ||
1137 !list_empty(&plug->cb_list));
Jens Axboe73c10102011-03-08 13:19:51 +01001138}
1139
Linus Torvalds1da177e2005-04-16 15:20:36 -07001140/*
1141 * tag stuff
1142 */
Christoph Hellwigfb3ccb52014-04-14 10:30:12 +02001143#define blk_rq_tagged(rq) \
1144 ((rq)->mq_ctx || ((rq)->cmd_flags & REQ_QUEUED))
Jens Axboe165125e2007-07-24 09:28:11 +02001145extern int blk_queue_start_tag(struct request_queue *, struct request *);
1146extern struct request *blk_queue_find_tag(struct request_queue *, int);
1147extern void blk_queue_end_tag(struct request_queue *, struct request *);
1148extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *);
1149extern void blk_queue_free_tags(struct request_queue *);
1150extern int blk_queue_resize_tags(struct request_queue *, int);
1151extern void blk_queue_invalidate_tags(struct request_queue *);
James Bottomley492dfb42006-08-30 15:48:45 -04001152extern struct blk_queue_tag *blk_init_tags(int);
1153extern void blk_free_tags(struct blk_queue_tag *);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001154
David C Somayajuluf583f492006-10-04 08:27:25 +02001155static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
1156 int tag)
1157{
1158 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
1159 return NULL;
1160 return bqt->tag_index[tag];
1161}
Christoph Hellwigdd3932e2010-09-16 20:51:46 +02001162
1163#define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
1164
1165extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
Dmitry Monakhovfbd9b092010-04-28 17:55:06 +04001166extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
1167 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
Martin K. Petersen4363ac72012-09-18 12:19:27 -04001168extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
1169 sector_t nr_sects, gfp_t gfp_mask, struct page *page);
Dmitry Monakhov3f14d792010-04-28 17:55:09 +04001170extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
Christoph Hellwigdd3932e2010-09-16 20:51:46 +02001171 sector_t nr_sects, gfp_t gfp_mask);
Christoph Hellwig2cf6d262010-08-18 05:29:10 -04001172static inline int sb_issue_discard(struct super_block *sb, sector_t block,
1173 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
David Woodhousefb2dce82008-08-05 18:01:53 +01001174{
Christoph Hellwig2cf6d262010-08-18 05:29:10 -04001175 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
1176 nr_blocks << (sb->s_blocksize_bits - 9),
1177 gfp_mask, flags);
David Woodhousefb2dce82008-08-05 18:01:53 +01001178}
Lukas Czernere6fa0be2010-10-27 21:30:04 -04001179static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
Theodore Ts'oa107e5a2010-10-27 23:44:47 -04001180 sector_t nr_blocks, gfp_t gfp_mask)
Lukas Czernere6fa0be2010-10-27 21:30:04 -04001181{
1182 return blkdev_issue_zeroout(sb->s_bdev,
1183 block << (sb->s_blocksize_bits - 9),
1184 nr_blocks << (sb->s_blocksize_bits - 9),
Theodore Ts'oa107e5a2010-10-27 23:44:47 -04001185 gfp_mask);
Lukas Czernere6fa0be2010-10-27 21:30:04 -04001186}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001187
Jens Axboe018e0442009-06-26 16:27:10 +02001188extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
Adel Gadllah0b07de82008-06-26 13:48:27 +02001189
Martin K. Peterseneb28d312010-02-26 00:20:37 -05001190enum blk_default_limits {
1191 BLK_MAX_SEGMENTS = 128,
1192 BLK_SAFE_MAX_SECTORS = 255,
1193 BLK_DEF_MAX_SECTORS = 1024,
1194 BLK_MAX_SEGMENT_SIZE = 65536,
1195 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
1196};
Milan Broz0e435ac2008-12-03 12:55:08 +01001197
Linus Torvalds1da177e2005-04-16 15:20:36 -07001198#define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
1199
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001200static inline unsigned long queue_bounce_pfn(struct request_queue *q)
1201{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001202 return q->limits.bounce_pfn;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001203}
1204
1205static inline unsigned long queue_segment_boundary(struct request_queue *q)
1206{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001207 return q->limits.seg_boundary_mask;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001208}
1209
1210static inline unsigned int queue_max_sectors(struct request_queue *q)
1211{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001212 return q->limits.max_sectors;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001213}
1214
1215static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1216{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001217 return q->limits.max_hw_sectors;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001218}
1219
Martin K. Petersen8a783622010-02-26 00:20:39 -05001220static inline unsigned short queue_max_segments(struct request_queue *q)
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001221{
Martin K. Petersen8a783622010-02-26 00:20:39 -05001222 return q->limits.max_segments;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001223}
1224
1225static inline unsigned int queue_max_segment_size(struct request_queue *q)
1226{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001227 return q->limits.max_segment_size;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001228}
1229
Martin K. Petersene1defc42009-05-22 17:17:49 -04001230static inline unsigned short queue_logical_block_size(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001231{
1232 int retval = 512;
1233
Martin K. Petersen025146e2009-05-22 17:17:51 -04001234 if (q && q->limits.logical_block_size)
1235 retval = q->limits.logical_block_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001236
1237 return retval;
1238}
1239
Martin K. Petersene1defc42009-05-22 17:17:49 -04001240static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001241{
Martin K. Petersene1defc42009-05-22 17:17:49 -04001242 return queue_logical_block_size(bdev_get_queue(bdev));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001243}
1244
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001245static inline unsigned int queue_physical_block_size(struct request_queue *q)
1246{
1247 return q->limits.physical_block_size;
1248}
1249
Martin K. Petersen892b6f92010-10-13 21:18:03 +02001250static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
Martin K. Petersenac481c22009-10-03 20:52:01 +02001251{
1252 return queue_physical_block_size(bdev_get_queue(bdev));
1253}
1254
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001255static inline unsigned int queue_io_min(struct request_queue *q)
1256{
1257 return q->limits.io_min;
1258}
1259
Martin K. Petersenac481c22009-10-03 20:52:01 +02001260static inline int bdev_io_min(struct block_device *bdev)
1261{
1262 return queue_io_min(bdev_get_queue(bdev));
1263}
1264
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001265static inline unsigned int queue_io_opt(struct request_queue *q)
1266{
1267 return q->limits.io_opt;
1268}
1269
Martin K. Petersenac481c22009-10-03 20:52:01 +02001270static inline int bdev_io_opt(struct block_device *bdev)
1271{
1272 return queue_io_opt(bdev_get_queue(bdev));
1273}
1274
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001275static inline int queue_alignment_offset(struct request_queue *q)
1276{
Martin K. Petersenac481c22009-10-03 20:52:01 +02001277 if (q->limits.misaligned)
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001278 return -1;
1279
Martin K. Petersenac481c22009-10-03 20:52:01 +02001280 return q->limits.alignment_offset;
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001281}
1282
Martin K. Petersene03a72e2010-01-11 03:21:51 -05001283static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
Martin K. Petersen81744ee2009-12-29 08:35:35 +01001284{
1285 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
Martin K. Petersene03a72e2010-01-11 03:21:51 -05001286 unsigned int alignment = (sector << 9) & (granularity - 1);
Martin K. Petersen81744ee2009-12-29 08:35:35 +01001287
Martin K. Petersene03a72e2010-01-11 03:21:51 -05001288 return (granularity + lim->alignment_offset - alignment)
1289 & (granularity - 1);
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001290}
1291
Martin K. Petersenac481c22009-10-03 20:52:01 +02001292static inline int bdev_alignment_offset(struct block_device *bdev)
1293{
1294 struct request_queue *q = bdev_get_queue(bdev);
1295
1296 if (q->limits.misaligned)
1297 return -1;
1298
1299 if (bdev != bdev->bd_contains)
1300 return bdev->bd_part->alignment_offset;
1301
1302 return q->limits.alignment_offset;
1303}
1304
Martin K. Petersen86b37282009-11-10 11:50:21 +01001305static inline int queue_discard_alignment(struct request_queue *q)
1306{
1307 if (q->limits.discard_misaligned)
1308 return -1;
1309
1310 return q->limits.discard_alignment;
1311}
1312
Martin K. Petersene03a72e2010-01-11 03:21:51 -05001313static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
Martin K. Petersen86b37282009-11-10 11:50:21 +01001314{
Linus Torvalds59771072012-12-19 07:18:35 -08001315 unsigned int alignment, granularity, offset;
Martin K. Petersendd3d1452010-01-11 03:21:48 -05001316
Martin K. Petersena934a002011-05-18 10:37:35 +02001317 if (!lim->max_discard_sectors)
1318 return 0;
1319
Linus Torvalds59771072012-12-19 07:18:35 -08001320 /* Why are these in bytes, not sectors? */
1321 alignment = lim->discard_alignment >> 9;
1322 granularity = lim->discard_granularity >> 9;
1323 if (!granularity)
1324 return 0;
1325
1326 /* Offset of the partition start in 'granularity' sectors */
1327 offset = sector_div(sector, granularity);
1328
1329 /* And why do we do this modulus *again* in blkdev_issue_discard()? */
1330 offset = (granularity + alignment - offset) % granularity;
1331
1332 /* Turn it back into bytes, gaah */
1333 return offset << 9;
Martin K. Petersen86b37282009-11-10 11:50:21 +01001334}
1335
Paolo Bonzinic6e66632012-08-02 09:48:50 +02001336static inline int bdev_discard_alignment(struct block_device *bdev)
1337{
1338 struct request_queue *q = bdev_get_queue(bdev);
1339
1340 if (bdev != bdev->bd_contains)
1341 return bdev->bd_part->discard_alignment;
1342
1343 return q->limits.discard_alignment;
1344}
1345
Martin K. Petersen98262f22009-12-03 09:24:48 +01001346static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1347{
Martin K. Petersena934a002011-05-18 10:37:35 +02001348 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
Martin K. Petersen98262f22009-12-03 09:24:48 +01001349 return 1;
1350
1351 return 0;
1352}
1353
1354static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1355{
1356 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1357}
1358
Martin K. Petersen4363ac72012-09-18 12:19:27 -04001359static inline unsigned int bdev_write_same(struct block_device *bdev)
1360{
1361 struct request_queue *q = bdev_get_queue(bdev);
1362
1363 if (q)
1364 return q->limits.max_write_same_sectors;
1365
1366 return 0;
1367}
1368
Jens Axboe165125e2007-07-24 09:28:11 +02001369static inline int queue_dma_alignment(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370{
Pete Wyckoff482eb682008-01-01 10:23:02 -05001371 return q ? q->dma_alignment : 511;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001372}
1373
Namhyung Kim14417792010-09-15 13:08:27 +02001374static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
FUJITA Tomonori87904072008-08-28 15:05:58 +09001375 unsigned int len)
1376{
1377 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
Namhyung Kim14417792010-09-15 13:08:27 +02001378 return !(addr & alignment) && !(len & alignment);
FUJITA Tomonori87904072008-08-28 15:05:58 +09001379}
1380
Linus Torvalds1da177e2005-04-16 15:20:36 -07001381/* assumes size > 256 */
1382static inline unsigned int blksize_bits(unsigned int size)
1383{
1384 unsigned int bits = 8;
1385 do {
1386 bits++;
1387 size >>= 1;
1388 } while (size > 256);
1389 return bits;
1390}
1391
Adrian Bunk2befb9e2005-09-10 00:27:17 -07001392static inline unsigned int block_size(struct block_device *bdev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001393{
1394 return bdev->bd_block_size;
1395}
1396
shaohua.li@intel.comf3876932011-05-06 11:34:32 -06001397static inline bool queue_flush_queueable(struct request_queue *q)
1398{
1399 return !q->flush_not_queueable;
1400}
1401
Linus Torvalds1da177e2005-04-16 15:20:36 -07001402typedef struct {struct page *v;} Sector;
1403
1404unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1405
1406static inline void put_dev_sector(Sector p)
1407{
1408 page_cache_release(p.v);
1409}
1410
1411struct work_struct;
Jens Axboe59c3d452014-04-08 09:15:35 -06001412int kblockd_schedule_work(struct work_struct *work);
1413int kblockd_schedule_delayed_work(struct delayed_work *dwork, unsigned long delay);
Jens Axboe8ab14592014-04-08 09:17:40 -06001414int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned long delay);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001415
Divyesh Shah91952912010-04-01 15:01:41 -07001416#ifdef CONFIG_BLK_CGROUP
Jens Axboe28f41972010-06-01 12:23:18 +02001417/*
1418 * This should not be using sched_clock(). A real patch is in progress
1419 * to fix this up, until that is in place we need to disable preemption
1420 * around sched_clock() in this function and set_io_start_time_ns().
1421 */
Divyesh Shah91952912010-04-01 15:01:41 -07001422static inline void set_start_time_ns(struct request *req)
1423{
Jens Axboe28f41972010-06-01 12:23:18 +02001424 preempt_disable();
Divyesh Shah91952912010-04-01 15:01:41 -07001425 req->start_time_ns = sched_clock();
Jens Axboe28f41972010-06-01 12:23:18 +02001426 preempt_enable();
Divyesh Shah91952912010-04-01 15:01:41 -07001427}
1428
1429static inline void set_io_start_time_ns(struct request *req)
1430{
Jens Axboe28f41972010-06-01 12:23:18 +02001431 preempt_disable();
Divyesh Shah91952912010-04-01 15:01:41 -07001432 req->io_start_time_ns = sched_clock();
Jens Axboe28f41972010-06-01 12:23:18 +02001433 preempt_enable();
Divyesh Shah91952912010-04-01 15:01:41 -07001434}
Divyesh Shah84c124d2010-04-09 08:31:19 +02001435
1436static inline uint64_t rq_start_time_ns(struct request *req)
1437{
1438 return req->start_time_ns;
1439}
1440
1441static inline uint64_t rq_io_start_time_ns(struct request *req)
1442{
1443 return req->io_start_time_ns;
1444}
Divyesh Shah91952912010-04-01 15:01:41 -07001445#else
1446static inline void set_start_time_ns(struct request *req) {}
1447static inline void set_io_start_time_ns(struct request *req) {}
Divyesh Shah84c124d2010-04-09 08:31:19 +02001448static inline uint64_t rq_start_time_ns(struct request *req)
1449{
1450 return 0;
1451}
1452static inline uint64_t rq_io_start_time_ns(struct request *req)
1453{
1454 return 0;
1455}
Divyesh Shah91952912010-04-01 15:01:41 -07001456#endif
1457
Linus Torvalds1da177e2005-04-16 15:20:36 -07001458#define MODULE_ALIAS_BLOCKDEV(major,minor) \
1459 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1460#define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1461 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1462
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001463#if defined(CONFIG_BLK_DEV_INTEGRITY)
1464
Jens Axboeb24498d2008-06-27 09:12:09 +02001465#define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */
1466#define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001467
1468struct blk_integrity_exchg {
1469 void *prot_buf;
1470 void *data_buf;
1471 sector_t sector;
1472 unsigned int data_size;
1473 unsigned short sector_size;
1474 const char *disk_name;
1475};
1476
1477typedef void (integrity_gen_fn) (struct blk_integrity_exchg *);
1478typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *);
1479typedef void (integrity_set_tag_fn) (void *, void *, unsigned int);
1480typedef void (integrity_get_tag_fn) (void *, void *, unsigned int);
1481
1482struct blk_integrity {
1483 integrity_gen_fn *generate_fn;
1484 integrity_vrfy_fn *verify_fn;
1485 integrity_set_tag_fn *set_tag_fn;
1486 integrity_get_tag_fn *get_tag_fn;
1487
1488 unsigned short flags;
1489 unsigned short tuple_size;
1490 unsigned short sector_size;
1491 unsigned short tag_size;
1492
1493 const char *name;
1494
1495 struct kobject kobj;
1496};
1497
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001498extern bool blk_integrity_is_initialized(struct gendisk *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001499extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
1500extern void blk_integrity_unregister(struct gendisk *);
Martin K. Petersenad7fce92008-10-01 03:38:39 -04001501extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
Martin K. Petersen13f05c82010-09-10 20:50:10 +02001502extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1503 struct scatterlist *);
1504extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1505extern int blk_integrity_merge_rq(struct request_queue *, struct request *,
1506 struct request *);
1507extern int blk_integrity_merge_bio(struct request_queue *, struct request *,
1508 struct bio *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001509
Jens Axboeb04accc2008-10-02 12:53:22 +02001510static inline
1511struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1512{
1513 return bdev->bd_disk->integrity;
1514}
1515
Martin K. Petersenb02739b2008-10-02 18:47:49 +02001516static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1517{
1518 return disk->integrity;
1519}
1520
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001521static inline int blk_integrity_rq(struct request *rq)
1522{
Martin K. Petersend442cc42008-07-16 16:09:06 -04001523 if (rq->bio == NULL)
1524 return 0;
1525
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001526 return bio_integrity(rq->bio);
1527}
1528
Martin K. Petersen13f05c82010-09-10 20:50:10 +02001529static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1530 unsigned int segs)
1531{
1532 q->limits.max_integrity_segments = segs;
1533}
1534
1535static inline unsigned short
1536queue_max_integrity_segments(struct request_queue *q)
1537{
1538 return q->limits.max_integrity_segments;
1539}
1540
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001541#else /* CONFIG_BLK_DEV_INTEGRITY */
1542
Stephen Rothwellfd832402012-01-12 09:17:30 +01001543struct bio;
1544struct block_device;
1545struct gendisk;
1546struct blk_integrity;
1547
1548static inline int blk_integrity_rq(struct request *rq)
1549{
1550 return 0;
1551}
1552static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1553 struct bio *b)
1554{
1555 return 0;
1556}
1557static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1558 struct bio *b,
1559 struct scatterlist *s)
1560{
1561 return 0;
1562}
1563static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1564{
1565 return 0;
1566}
1567static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1568{
1569 return NULL;
1570}
1571static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1572{
1573 return 0;
1574}
1575static inline int blk_integrity_register(struct gendisk *d,
1576 struct blk_integrity *b)
1577{
1578 return 0;
1579}
1580static inline void blk_integrity_unregister(struct gendisk *d)
1581{
1582}
1583static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1584 unsigned int segs)
1585{
1586}
1587static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1588{
1589 return 0;
1590}
1591static inline int blk_integrity_merge_rq(struct request_queue *rq,
1592 struct request *r1,
1593 struct request *r2)
1594{
1595 return 0;
1596}
1597static inline int blk_integrity_merge_bio(struct request_queue *rq,
1598 struct request *r,
1599 struct bio *b)
1600{
1601 return 0;
1602}
1603static inline bool blk_integrity_is_initialized(struct gendisk *g)
1604{
1605 return 0;
1606}
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001607
1608#endif /* CONFIG_BLK_DEV_INTEGRITY */
1609
Al Viro08f85852007-10-08 13:26:20 -04001610struct block_device_operations {
Al Virod4430d622008-03-02 09:09:22 -05001611 int (*open) (struct block_device *, fmode_t);
Al Virodb2a1442013-05-05 21:52:57 -04001612 void (*release) (struct gendisk *, fmode_t);
Matthew Wilcox47a191f2014-06-04 16:07:46 -07001613 int (*rw_page)(struct block_device *, sector_t, struct page *, int rw);
Al Virod4430d622008-03-02 09:09:22 -05001614 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1615 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
Al Viro08f85852007-10-08 13:26:20 -04001616 int (*direct_access) (struct block_device *, sector_t,
1617 void **, unsigned long *);
Tejun Heo77ea8872010-12-08 20:57:37 +01001618 unsigned int (*check_events) (struct gendisk *disk,
1619 unsigned int clearing);
1620 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
Al Viro08f85852007-10-08 13:26:20 -04001621 int (*media_changed) (struct gendisk *);
Tejun Heoc3e33e02010-05-15 20:09:29 +02001622 void (*unlock_native_capacity) (struct gendisk *);
Al Viro08f85852007-10-08 13:26:20 -04001623 int (*revalidate_disk) (struct gendisk *);
1624 int (*getgeo)(struct block_device *, struct hd_geometry *);
Nitin Guptab3a27d02010-05-17 11:02:43 +05301625 /* this callback is with swap_lock and sometimes page table lock held */
1626 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
Al Viro08f85852007-10-08 13:26:20 -04001627 struct module *owner;
1628};
1629
Al Viro633a08b2007-08-29 20:34:12 -04001630extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1631 unsigned long);
Matthew Wilcox47a191f2014-06-04 16:07:46 -07001632extern int bdev_read_page(struct block_device *, sector_t, struct page *);
1633extern int bdev_write_page(struct block_device *, sector_t, struct page *,
1634 struct writeback_control *);
David Howells93614012006-09-30 20:45:40 +02001635#else /* CONFIG_BLOCK */
Fabian Frederickac13a822014-06-04 16:06:27 -07001636
1637struct block_device;
1638
David Howells93614012006-09-30 20:45:40 +02001639/*
1640 * stubs for when the block layer is configured out
1641 */
1642#define buffer_heads_over_limit 0
1643
David Howells93614012006-09-30 20:45:40 +02001644static inline long nr_blockdev_pages(void)
1645{
1646 return 0;
1647}
1648
Jens Axboe1f940bd2011-03-11 20:17:08 +01001649struct blk_plug {
1650};
1651
1652static inline void blk_start_plug(struct blk_plug *plug)
Jens Axboe73c10102011-03-08 13:19:51 +01001653{
1654}
1655
Jens Axboe1f940bd2011-03-11 20:17:08 +01001656static inline void blk_finish_plug(struct blk_plug *plug)
Jens Axboe73c10102011-03-08 13:19:51 +01001657{
1658}
1659
Jens Axboe1f940bd2011-03-11 20:17:08 +01001660static inline void blk_flush_plug(struct task_struct *task)
Jens Axboe73c10102011-03-08 13:19:51 +01001661{
1662}
1663
Jens Axboea237c1c2011-04-16 13:27:55 +02001664static inline void blk_schedule_flush_plug(struct task_struct *task)
1665{
1666}
1667
1668
Jens Axboe73c10102011-03-08 13:19:51 +01001669static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1670{
1671 return false;
1672}
1673
Fabian Frederickac13a822014-06-04 16:06:27 -07001674static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
1675 sector_t *error_sector)
1676{
1677 return 0;
1678}
1679
David Howells93614012006-09-30 20:45:40 +02001680#endif /* CONFIG_BLOCK */
1681
Linus Torvalds1da177e2005-04-16 15:20:36 -07001682#endif