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Linus Torvalds1da177e2005-04-16 15:20:36 -07001#ifndef _LINUX_BLKDEV_H
2#define _LINUX_BLKDEV_H
3
Jens Axboef5ff8422007-09-21 09:19:54 +02004#ifdef CONFIG_BLOCK
5
Andrew Mortonbcfd8d32006-08-31 12:56:06 +02006#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07007#include <linux/major.h>
8#include <linux/genhd.h>
9#include <linux/list.h>
10#include <linux/timer.h>
11#include <linux/workqueue.h>
12#include <linux/pagemap.h>
13#include <linux/backing-dev.h>
14#include <linux/wait.h>
15#include <linux/mempool.h>
16#include <linux/bio.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/stringify.h>
Hugh Dickins3e6053d2008-09-11 10:57:55 +020018#include <linux/gfp.h>
FUJITA Tomonorid351af02007-07-09 12:40:35 +020019#include <linux/bsg.h>
Jens Axboec7c22e42008-09-13 20:26:01 +020020#include <linux/smp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021
22#include <asm/scatterlist.h>
23
Paul Gortmakerde477252011-05-26 13:46:22 -040024struct module;
Christoph Hellwig21b2f0c2006-03-22 17:52:04 +010025struct scsi_ioctl_command;
26
Linus Torvalds1da177e2005-04-16 15:20:36 -070027struct request_queue;
Linus Torvalds1da177e2005-04-16 15:20:36 -070028struct elevator_queue;
Linus Torvalds1da177e2005-04-16 15:20:36 -070029struct request_pm_state;
Jens Axboe2056a782006-03-23 20:00:26 +010030struct blk_trace;
Jens Axboe3d6392c2007-07-09 12:38:05 +020031struct request;
32struct sg_io_hdr;
Mike Christieaa387cc2011-07-31 22:05:09 +020033struct bsg_job;
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
35#define BLKDEV_MIN_RQ 4
36#define BLKDEV_MAX_RQ 128 /* Default maximum */
37
Linus Torvalds1da177e2005-04-16 15:20:36 -070038struct request;
Tejun Heo8ffdc652006-01-06 09:49:03 +010039typedef void (rq_end_io_fn)(struct request *, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -070040
41struct request_list {
Jens Axboe1faa16d2009-04-06 14:48:01 +020042 /*
43 * count[], starved[], and wait[] are indexed by
44 * BLK_RW_SYNC/BLK_RW_ASYNC
45 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070046 int count[2];
47 int starved[2];
Tejun Heocb98fc82005-10-28 08:29:39 +020048 int elvpriv;
Linus Torvalds1da177e2005-04-16 15:20:36 -070049 mempool_t *rq_pool;
50 wait_queue_head_t wait[2];
Linus Torvalds1da177e2005-04-16 15:20:36 -070051};
52
Jens Axboe4aff5e22006-08-10 08:44:47 +020053/*
54 * request command types
55 */
56enum rq_cmd_type_bits {
57 REQ_TYPE_FS = 1, /* fs request */
58 REQ_TYPE_BLOCK_PC, /* scsi command */
59 REQ_TYPE_SENSE, /* sense request */
60 REQ_TYPE_PM_SUSPEND, /* suspend request */
61 REQ_TYPE_PM_RESUME, /* resume request */
62 REQ_TYPE_PM_SHUTDOWN, /* shutdown request */
Jens Axboe4aff5e22006-08-10 08:44:47 +020063 REQ_TYPE_SPECIAL, /* driver defined type */
Jens Axboe4aff5e22006-08-10 08:44:47 +020064 /*
65 * for ATA/ATAPI devices. this really doesn't belong here, ide should
66 * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
67 * private REQ_LB opcodes to differentiate what type of request this is
68 */
Jens Axboe4aff5e22006-08-10 08:44:47 +020069 REQ_TYPE_ATA_TASKFILE,
Jens Axboecea28852006-10-12 15:08:45 +020070 REQ_TYPE_ATA_PC,
Jens Axboe4aff5e22006-08-10 08:44:47 +020071};
72
Linus Torvalds1da177e2005-04-16 15:20:36 -070073#define BLK_MAX_CDB 16
74
75/*
Jens Axboe63a71382008-02-08 12:41:03 +010076 * try to put the fields that are referenced together in the same cacheline.
Wanlong Gao4d0d98b2011-06-13 10:45:38 +020077 * if you modify this structure, be sure to check block/blk-core.c:blk_rq_init()
Jens Axboe63a71382008-02-08 12:41:03 +010078 * as well!
Linus Torvalds1da177e2005-04-16 15:20:36 -070079 */
80struct request {
Jens Axboeff856ba2006-01-09 16:02:34 +010081 struct list_head queuelist;
Jens Axboec7c22e42008-09-13 20:26:01 +020082 struct call_single_data csd;
Jens Axboeff856ba2006-01-09 16:02:34 +010083
Jens Axboe165125e2007-07-24 09:28:11 +020084 struct request_queue *q;
Jens Axboee6a1c872006-08-10 09:00:21 +020085
Jens Axboe4aff5e22006-08-10 08:44:47 +020086 unsigned int cmd_flags;
87 enum rq_cmd_type_bits cmd_type;
Jens Axboe242f9dc2008-09-14 05:55:09 -070088 unsigned long atomic_flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -070089
Richard Kennedy181fdde2010-03-19 08:58:16 +010090 int cpu;
91
Tejun Heoa2dec7b2009-05-07 22:24:44 +090092 /* the following two fields are internal, NEVER access directly */
Tejun Heoa2dec7b2009-05-07 22:24:44 +090093 unsigned int __data_len; /* total data len */
Richard Kennedy181fdde2010-03-19 08:58:16 +010094 sector_t __sector; /* sector cursor */
Linus Torvalds1da177e2005-04-16 15:20:36 -070095
96 struct bio *bio;
97 struct bio *biotail;
98
Jens Axboe98170642006-07-28 09:23:08 +020099 struct hlist_node hash; /* merge hash */
Jens Axboee6a1c872006-08-10 09:00:21 +0200100 /*
101 * The rb_node is only used inside the io scheduler, requests
102 * are pruned when moved to the dispatch queue. So let the
Mike Snitzerc1867942011-02-11 11:08:00 +0100103 * completion_data share space with the rb_node.
Jens Axboee6a1c872006-08-10 09:00:21 +0200104 */
105 union {
106 struct rb_node rb_node; /* sort/lookup */
Mike Snitzerc1867942011-02-11 11:08:00 +0100107 void *completion_data;
Jens Axboee6a1c872006-08-10 09:00:21 +0200108 };
Jens Axboe98170642006-07-28 09:23:08 +0200109
Jens Axboeff7d1452006-07-12 14:04:37 +0200110 /*
Vivek Goyal7f1dc8a2010-04-21 17:44:16 +0200111 * Three pointers are available for the IO schedulers, if they need
Mike Snitzerc1867942011-02-11 11:08:00 +0100112 * more they have to dynamically allocate it. Flush requests are
113 * never put on the IO scheduler. So let the flush fields share
Tejun Heoa612fdd2011-12-14 00:33:41 +0100114 * space with the elevator data.
Jens Axboeff7d1452006-07-12 14:04:37 +0200115 */
Mike Snitzerc1867942011-02-11 11:08:00 +0100116 union {
Tejun Heoa612fdd2011-12-14 00:33:41 +0100117 struct {
118 struct io_cq *icq;
119 void *priv[2];
120 } elv;
121
Mike Snitzerc1867942011-02-11 11:08:00 +0100122 struct {
123 unsigned int seq;
124 struct list_head list;
Jeff Moyer4853aba2011-08-15 21:37:25 +0200125 rq_end_io_fn *saved_end_io;
Mike Snitzerc1867942011-02-11 11:08:00 +0100126 } flush;
127 };
Jens Axboeff7d1452006-07-12 14:04:37 +0200128
Jens Axboe8f34ee72006-06-13 09:02:34 +0200129 struct gendisk *rq_disk;
Jerome Marchand09e099d2011-01-05 16:57:38 +0100130 struct hd_struct *part;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131 unsigned long start_time;
Divyesh Shah91952912010-04-01 15:01:41 -0700132#ifdef CONFIG_BLK_CGROUP
133 unsigned long long start_time_ns;
134 unsigned long long io_start_time_ns; /* when passed to hardware */
135#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136 /* Number of scatter-gather DMA addr+len pairs after
137 * physical address coalescing is performed.
138 */
139 unsigned short nr_phys_segments;
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200140#if defined(CONFIG_BLK_DEV_INTEGRITY)
141 unsigned short nr_integrity_segments;
142#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700143
Jens Axboe8f34ee72006-06-13 09:02:34 +0200144 unsigned short ioprio;
145
Richard Kennedy181fdde2010-03-19 08:58:16 +0100146 int ref_count;
147
Tejun Heo731ec492009-04-23 11:05:20 +0900148 void *special; /* opaque pointer available for LLD use */
149 char *buffer; /* kaddr of the current segment if available */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150
Jens Axboecdd60262006-07-28 09:32:07 +0200151 int tag;
152 int errors;
153
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 /*
155 * when request is used as a packet command carrier
156 */
FUJITA Tomonorid7e3c322008-04-29 09:54:39 +0200157 unsigned char __cmd[BLK_MAX_CDB];
158 unsigned char *cmd;
Richard Kennedy181fdde2010-03-19 08:58:16 +0100159 unsigned short cmd_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160
FUJITA Tomonori7a85f882008-03-04 11:17:11 +0100161 unsigned int extra_len; /* length of alignment and padding */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162 unsigned int sense_len;
Tejun Heoc3a4d782009-05-07 22:24:37 +0900163 unsigned int resid_len; /* residual count */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164 void *sense;
165
Jens Axboe242f9dc2008-09-14 05:55:09 -0700166 unsigned long deadline;
167 struct list_head timeout_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700168 unsigned int timeout;
Mike Christie17e01f22005-11-11 05:31:37 -0600169 int retries;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170
171 /*
Jens Axboec00895a2006-09-30 20:29:12 +0200172 * completion callback.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 */
174 rq_end_io_fn *end_io;
175 void *end_io_data;
FUJITA Tomonoriabae1fd2007-07-16 08:52:14 +0200176
177 /* for bidi */
178 struct request *next_rq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179};
180
Fernando Luis Vázquez Cao766ca442008-08-14 09:59:13 +0200181static inline unsigned short req_get_ioprio(struct request *req)
182{
183 return req->ioprio;
184}
185
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186/*
Jens Axboe4aff5e22006-08-10 08:44:47 +0200187 * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188 * requests. Some step values could eventually be made generic.
189 */
190struct request_pm_state
191{
192 /* PM state machine step value, currently driver specific */
193 int pm_step;
194 /* requested PM state value (S1, S2, S3, S4, ...) */
195 u32 pm_state;
196 void* data; /* for driver use */
197};
198
199#include <linux/elevator.h>
200
Jens Axboe165125e2007-07-24 09:28:11 +0200201typedef void (request_fn_proc) (struct request_queue *q);
Christoph Hellwig5a7bbad2011-09-12 12:12:01 +0200202typedef void (make_request_fn) (struct request_queue *q, struct bio *bio);
Jens Axboe165125e2007-07-24 09:28:11 +0200203typedef int (prep_rq_fn) (struct request_queue *, struct request *);
James Bottomley28018c22010-07-01 19:49:17 +0900204typedef void (unprep_rq_fn) (struct request_queue *, struct request *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205
206struct bio_vec;
Alasdair G Kergoncc371e62008-07-03 09:53:43 +0200207struct bvec_merge_data {
208 struct block_device *bi_bdev;
209 sector_t bi_sector;
210 unsigned bi_size;
211 unsigned long bi_rw;
212};
213typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *,
214 struct bio_vec *);
Jens Axboeff856ba2006-01-09 16:02:34 +0100215typedef void (softirq_done_fn)(struct request *);
Tejun Heo2fb98e82008-02-19 11:36:53 +0100216typedef int (dma_drain_needed_fn)(struct request *);
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +0200217typedef int (lld_busy_fn) (struct request_queue *q);
Mike Christieaa387cc2011-07-31 22:05:09 +0200218typedef int (bsg_job_fn) (struct bsg_job *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219
Jens Axboe242f9dc2008-09-14 05:55:09 -0700220enum blk_eh_timer_return {
221 BLK_EH_NOT_HANDLED,
222 BLK_EH_HANDLED,
223 BLK_EH_RESET_TIMER,
224};
225
226typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
227
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228enum blk_queue_state {
229 Queue_down,
230 Queue_up,
231};
232
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233struct blk_queue_tag {
234 struct request **tag_index; /* map of busy tags */
235 unsigned long *tag_map; /* bit map of free/busy tags */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236 int busy; /* current depth */
237 int max_depth; /* what we will send to device */
Tejun Heoba025082005-08-05 13:28:11 -0700238 int real_max_depth; /* what the array can hold */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 atomic_t refcnt; /* map can be shared */
240};
241
FUJITA Tomonoriabf54392008-08-16 14:10:05 +0900242#define BLK_SCSI_MAX_CMDS (256)
243#define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
244
Martin K. Petersen025146e2009-05-22 17:17:51 -0400245struct queue_limits {
246 unsigned long bounce_pfn;
247 unsigned long seg_boundary_mask;
248
249 unsigned int max_hw_sectors;
250 unsigned int max_sectors;
251 unsigned int max_segment_size;
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400252 unsigned int physical_block_size;
253 unsigned int alignment_offset;
254 unsigned int io_min;
255 unsigned int io_opt;
Christoph Hellwig67efc922009-09-30 13:54:20 +0200256 unsigned int max_discard_sectors;
Martin K. Petersen86b37282009-11-10 11:50:21 +0100257 unsigned int discard_granularity;
258 unsigned int discard_alignment;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400259
260 unsigned short logical_block_size;
Martin K. Petersen8a783622010-02-26 00:20:39 -0500261 unsigned short max_segments;
Martin K. Petersen13f05c82010-09-10 20:50:10 +0200262 unsigned short max_integrity_segments;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400263
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400264 unsigned char misaligned;
Martin K. Petersen86b37282009-11-10 11:50:21 +0100265 unsigned char discard_misaligned;
Martin K. Petersene692cb62010-12-01 19:41:49 +0100266 unsigned char cluster;
Martin K. Petersena934a002011-05-18 10:37:35 +0200267 unsigned char discard_zeroes_data;
Martin K. Petersen025146e2009-05-22 17:17:51 -0400268};
269
Richard Kennedyd7b76302011-07-13 21:17:23 +0200270struct request_queue {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 /*
272 * Together with queue_head for cacheline sharing
273 */
274 struct list_head queue_head;
275 struct request *last_merge;
Jens Axboeb374d182008-10-31 10:05:07 +0100276 struct elevator_queue *elevator;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277
278 /*
279 * the queue request freelist, one for reads and one for writes
280 */
281 struct request_list rq;
282
283 request_fn_proc *request_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284 make_request_fn *make_request_fn;
285 prep_rq_fn *prep_rq_fn;
James Bottomley28018c22010-07-01 19:49:17 +0900286 unprep_rq_fn *unprep_rq_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 merge_bvec_fn *merge_bvec_fn;
Jens Axboeff856ba2006-01-09 16:02:34 +0100288 softirq_done_fn *softirq_done_fn;
Jens Axboe242f9dc2008-09-14 05:55:09 -0700289 rq_timed_out_fn *rq_timed_out_fn;
Tejun Heo2fb98e82008-02-19 11:36:53 +0100290 dma_drain_needed_fn *dma_drain_needed;
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +0200291 lld_busy_fn *lld_busy_fn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292
293 /*
Tejun Heo8922e162005-10-20 16:23:44 +0200294 * Dispatch queue sorting
295 */
Jens Axboe1b47f532005-10-20 16:37:00 +0200296 sector_t end_sector;
Tejun Heo8922e162005-10-20 16:23:44 +0200297 struct request *boundary_rq;
Tejun Heo8922e162005-10-20 16:23:44 +0200298
299 /*
Jens Axboe3cca6dc2011-03-02 11:08:00 -0500300 * Delayed queue handling
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 */
Jens Axboe3cca6dc2011-03-02 11:08:00 -0500302 struct delayed_work delay_work;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303
304 struct backing_dev_info backing_dev_info;
305
306 /*
307 * The queue owner gets to use this for whatever they like.
308 * ll_rw_blk doesn't touch it.
309 */
310 void *queuedata;
311
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 * various queue flags, see QUEUE_* below
314 */
315 unsigned long queue_flags;
316
317 /*
Tejun Heoa73f7302011-12-14 00:33:37 +0100318 * ida allocated id for this queue. Used to index queues from
319 * ioctx.
320 */
321 int id;
322
323 /*
Richard Kennedyd7b76302011-07-13 21:17:23 +0200324 * queue needs bounce pages for pages above this limit
325 */
326 gfp_t bounce_gfp;
327
328 /*
152587d2005-04-12 16:22:06 -0500329 * protects queue structures from reentrancy. ->__queue_lock should
330 * _never_ be used directly, it is queue private. always use
331 * ->queue_lock.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 */
152587d2005-04-12 16:22:06 -0500333 spinlock_t __queue_lock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700334 spinlock_t *queue_lock;
335
336 /*
337 * queue kobject
338 */
339 struct kobject kobj;
340
341 /*
342 * queue settings
343 */
344 unsigned long nr_requests; /* Max # of requests */
345 unsigned int nr_congestion_on;
346 unsigned int nr_congestion_off;
347 unsigned int nr_batching;
348
James Bottomleyfa0ccd82008-01-10 11:30:36 -0600349 unsigned int dma_drain_size;
Richard Kennedyd7b76302011-07-13 21:17:23 +0200350 void *dma_drain_buffer;
Tejun Heoe3790c72008-03-04 11:18:17 +0100351 unsigned int dma_pad_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352 unsigned int dma_alignment;
353
354 struct blk_queue_tag *queue_tags;
Jens Axboe6eca9002007-10-25 10:14:47 +0200355 struct list_head tag_busy_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356
Tejun Heo15853af2005-11-10 08:52:05 +0100357 unsigned int nr_sorted;
Jens Axboe0a7ae2f2009-05-20 08:54:31 +0200358 unsigned int in_flight[2];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359
Jens Axboe242f9dc2008-09-14 05:55:09 -0700360 unsigned int rq_timeout;
361 struct timer_list timeout;
362 struct list_head timeout_list;
363
Tejun Heoa612fdd2011-12-14 00:33:41 +0100364 struct list_head icq_list;
365
Martin K. Petersen025146e2009-05-22 17:17:51 -0400366 struct queue_limits limits;
367
Linus Torvalds1da177e2005-04-16 15:20:36 -0700368 /*
369 * sg stuff
370 */
371 unsigned int sg_timeout;
372 unsigned int sg_reserved_size;
Christoph Lameter19460892005-06-23 00:08:19 -0700373 int node;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700374#ifdef CONFIG_BLK_DEV_IO_TRACE
Jens Axboe2056a782006-03-23 20:00:26 +0100375 struct blk_trace *blk_trace;
Alexey Dobriyan6c5c9342006-09-29 01:59:40 -0700376#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377 /*
Tejun Heo4913efe2010-09-03 11:56:16 +0200378 * for flush operations
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379 */
Tejun Heo4913efe2010-09-03 11:56:16 +0200380 unsigned int flush_flags;
shaohua.li@intel.comf3876932011-05-06 11:34:32 -0600381 unsigned int flush_not_queueable:1;
shaohua.li@intel.com3ac0cc42011-05-06 11:34:41 -0600382 unsigned int flush_queue_delayed:1;
Tejun Heoae1b1532011-01-25 12:43:54 +0100383 unsigned int flush_pending_idx:1;
384 unsigned int flush_running_idx:1;
385 unsigned long flush_pending_since;
386 struct list_head flush_queue[2];
387 struct list_head flush_data_in_flight;
Tejun Heodd4c1332010-09-03 11:56:16 +0200388 struct request flush_rq;
Al Viro483f4af2006-03-18 18:34:37 -0500389
390 struct mutex sysfs_lock;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200391
392#if defined(CONFIG_BLK_DEV_BSG)
Mike Christieaa387cc2011-07-31 22:05:09 +0200393 bsg_job_fn *bsg_job_fn;
394 int bsg_job_size;
FUJITA Tomonorid351af02007-07-09 12:40:35 +0200395 struct bsg_class_device bsg_dev;
396#endif
Vivek Goyale43473b2010-09-15 17:06:35 -0400397
398#ifdef CONFIG_BLK_DEV_THROTTLING
399 /* Throttle data */
400 struct throtl_data *td;
401#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402};
403
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404#define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
405#define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
Jens Axboe1faa16d2009-04-06 14:48:01 +0200406#define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
407#define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408#define QUEUE_FLAG_DEAD 5 /* queue being torn down */
Jens Axboec21e6be2011-04-19 13:32:46 +0200409#define QUEUE_FLAG_ELVSWITCH 6 /* don't use elevator, just do FIFO */
410#define QUEUE_FLAG_BIDI 7 /* queue supports bidi requests */
411#define QUEUE_FLAG_NOMERGES 8 /* disable merge attempts */
Dan Williams5757a6d2011-07-23 20:44:25 +0200412#define QUEUE_FLAG_SAME_COMP 9 /* complete on same CPU-group */
Jens Axboec21e6be2011-04-19 13:32:46 +0200413#define QUEUE_FLAG_FAIL_IO 10 /* fake timeout */
414#define QUEUE_FLAG_STACKABLE 11 /* supports request stacking */
415#define QUEUE_FLAG_NONROT 12 /* non-rotational device (SSD) */
Fernando Luis Vázquez Cao88e740f2008-10-27 18:44:46 +0900416#define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
Jens Axboec21e6be2011-04-19 13:32:46 +0200417#define QUEUE_FLAG_IO_STAT 13 /* do IO stats */
418#define QUEUE_FLAG_DISCARD 14 /* supports DISCARD */
419#define QUEUE_FLAG_NOXMERGES 15 /* No extended merges */
420#define QUEUE_FLAG_ADD_RANDOM 16 /* Contributes to random pool */
421#define QUEUE_FLAG_SECDISCARD 17 /* supports SECDISCARD */
Dan Williams5757a6d2011-07-23 20:44:25 +0200422#define QUEUE_FLAG_SAME_FORCE 18 /* force complete on same CPU */
Jens Axboebc58ba92009-01-23 10:54:44 +0100423
424#define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
Jens Axboe01e97f62009-09-03 20:06:47 +0200425 (1 << QUEUE_FLAG_STACKABLE) | \
Jens Axboee2e1a142010-06-09 10:42:09 +0200426 (1 << QUEUE_FLAG_SAME_COMP) | \
427 (1 << QUEUE_FLAG_ADD_RANDOM))
Tejun Heo797e7db2006-01-06 09:51:03 +0100428
Linus Torvalds8f45c1a2008-04-29 10:16:38 -0700429static inline int queue_is_locked(struct request_queue *q)
430{
Jens Axboe7663c1e2008-04-29 21:31:27 +0200431#ifdef CONFIG_SMP
Linus Torvalds8f45c1a2008-04-29 10:16:38 -0700432 spinlock_t *lock = q->queue_lock;
433 return lock && spin_is_locked(lock);
Jens Axboe7663c1e2008-04-29 21:31:27 +0200434#else
435 return 1;
436#endif
Linus Torvalds8f45c1a2008-04-29 10:16:38 -0700437}
438
Nick Piggin75ad23b2008-04-29 14:48:33 +0200439static inline void queue_flag_set_unlocked(unsigned int flag,
440 struct request_queue *q)
441{
442 __set_bit(flag, &q->queue_flags);
443}
444
Jens Axboee48ec692008-07-03 13:18:54 +0200445static inline int queue_flag_test_and_clear(unsigned int flag,
446 struct request_queue *q)
447{
448 WARN_ON_ONCE(!queue_is_locked(q));
449
450 if (test_bit(flag, &q->queue_flags)) {
451 __clear_bit(flag, &q->queue_flags);
452 return 1;
453 }
454
455 return 0;
456}
457
458static inline int queue_flag_test_and_set(unsigned int flag,
459 struct request_queue *q)
460{
461 WARN_ON_ONCE(!queue_is_locked(q));
462
463 if (!test_bit(flag, &q->queue_flags)) {
464 __set_bit(flag, &q->queue_flags);
465 return 0;
466 }
467
468 return 1;
469}
470
Nick Piggin75ad23b2008-04-29 14:48:33 +0200471static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
472{
Linus Torvalds8f45c1a2008-04-29 10:16:38 -0700473 WARN_ON_ONCE(!queue_is_locked(q));
Nick Piggin75ad23b2008-04-29 14:48:33 +0200474 __set_bit(flag, &q->queue_flags);
475}
476
477static inline void queue_flag_clear_unlocked(unsigned int flag,
478 struct request_queue *q)
479{
480 __clear_bit(flag, &q->queue_flags);
481}
482
Jens Axboe0a7ae2f2009-05-20 08:54:31 +0200483static inline int queue_in_flight(struct request_queue *q)
484{
485 return q->in_flight[0] + q->in_flight[1];
486}
487
Nick Piggin75ad23b2008-04-29 14:48:33 +0200488static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
489{
Linus Torvalds8f45c1a2008-04-29 10:16:38 -0700490 WARN_ON_ONCE(!queue_is_locked(q));
Nick Piggin75ad23b2008-04-29 14:48:33 +0200491 __clear_bit(flag, &q->queue_flags);
492}
493
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494#define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
495#define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
Tejun Heo34f60552011-12-14 00:33:37 +0100496#define blk_queue_dead(q) test_bit(QUEUE_FLAG_DEAD, &(q)->queue_flags)
Alan D. Brunelleac9fafa2008-04-29 14:44:19 +0200497#define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
Alan D. Brunelle488991e2010-01-29 09:04:08 +0100498#define blk_queue_noxmerges(q) \
499 test_bit(QUEUE_FLAG_NOXMERGES, &(q)->queue_flags)
Jens Axboea68bbdd2008-09-24 13:03:33 +0200500#define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
Jens Axboebc58ba92009-01-23 10:54:44 +0100501#define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
Jens Axboee2e1a142010-06-09 10:42:09 +0200502#define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
Kiyoshi Ueda4ee5eaf2008-09-18 10:46:13 -0400503#define blk_queue_stackable(q) \
504 test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
Christoph Hellwigc15227d2009-09-30 13:52:12 +0200505#define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
Adrian Hunter8d57a982010-08-11 14:17:49 -0700506#define blk_queue_secdiscard(q) (blk_queue_discard(q) && \
507 test_bit(QUEUE_FLAG_SECDISCARD, &(q)->queue_flags))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508
Christoph Hellwig33659eb2010-08-07 18:17:56 +0200509#define blk_noretry_request(rq) \
510 ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \
511 REQ_FAILFAST_DRIVER))
Jens Axboe4aff5e22006-08-10 08:44:47 +0200512
Christoph Hellwig33659eb2010-08-07 18:17:56 +0200513#define blk_account_rq(rq) \
514 (((rq)->cmd_flags & REQ_STARTED) && \
515 ((rq)->cmd_type == REQ_TYPE_FS || \
516 ((rq)->cmd_flags & REQ_DISCARD)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518#define blk_pm_request(rq) \
Christoph Hellwig33659eb2010-08-07 18:17:56 +0200519 ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND || \
520 (rq)->cmd_type == REQ_TYPE_PM_RESUME)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700521
Jens Axboeab780f12008-08-26 10:25:02 +0200522#define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
FUJITA Tomonoriabae1fd2007-07-16 08:52:14 +0200523#define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
Kiyoshi Ueda336cdb42007-12-11 17:40:30 -0500524/* rq->queuelist of dequeued request must be list_empty() */
525#define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526
527#define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
528
Jens Axboe4aff5e22006-08-10 08:44:47 +0200529#define rq_data_dir(rq) ((rq)->cmd_flags & 1)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530
Martin K. Petersene692cb62010-12-01 19:41:49 +0100531static inline unsigned int blk_queue_cluster(struct request_queue *q)
532{
533 return q->limits.cluster;
534}
535
Jens Axboe9e2585a2006-07-28 09:26:13 +0200536/*
Jens Axboe1faa16d2009-04-06 14:48:01 +0200537 * We regard a request as sync, if either a read or a sync write
Jens Axboe9e2585a2006-07-28 09:26:13 +0200538 */
Jens Axboe1faa16d2009-04-06 14:48:01 +0200539static inline bool rw_is_sync(unsigned int rw_flags)
540{
Christoph Hellwig7b6d91d2010-08-07 18:20:39 +0200541 return !(rw_flags & REQ_WRITE) || (rw_flags & REQ_SYNC);
Jens Axboe1faa16d2009-04-06 14:48:01 +0200542}
543
544static inline bool rq_is_sync(struct request *rq)
545{
546 return rw_is_sync(rq->cmd_flags);
547}
548
Jens Axboe1faa16d2009-04-06 14:48:01 +0200549static inline int blk_queue_full(struct request_queue *q, int sync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550{
Jens Axboe1faa16d2009-04-06 14:48:01 +0200551 if (sync)
552 return test_bit(QUEUE_FLAG_SYNCFULL, &q->queue_flags);
553 return test_bit(QUEUE_FLAG_ASYNCFULL, &q->queue_flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554}
555
Jens Axboe1faa16d2009-04-06 14:48:01 +0200556static inline void blk_set_queue_full(struct request_queue *q, int sync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557{
Jens Axboe1faa16d2009-04-06 14:48:01 +0200558 if (sync)
559 queue_flag_set(QUEUE_FLAG_SYNCFULL, q);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 else
Jens Axboe1faa16d2009-04-06 14:48:01 +0200561 queue_flag_set(QUEUE_FLAG_ASYNCFULL, q);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562}
563
Jens Axboe1faa16d2009-04-06 14:48:01 +0200564static inline void blk_clear_queue_full(struct request_queue *q, int sync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565{
Jens Axboe1faa16d2009-04-06 14:48:01 +0200566 if (sync)
567 queue_flag_clear(QUEUE_FLAG_SYNCFULL, q);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 else
Jens Axboe1faa16d2009-04-06 14:48:01 +0200569 queue_flag_clear(QUEUE_FLAG_ASYNCFULL, q);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570}
571
572
573/*
574 * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may
575 * it already be started by driver.
576 */
577#define RQ_NOMERGE_FLAGS \
Christoph Hellwig02e031c2010-11-10 14:54:09 +0100578 (REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579#define rq_mergeable(rq) \
David Woodhousee17fc0a2008-08-09 16:42:20 +0100580 (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \
Christoph Hellwig33659eb2010-08-07 18:17:56 +0200581 (((rq)->cmd_flags & REQ_DISCARD) || \
582 (rq)->cmd_type == REQ_TYPE_FS))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583
584/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585 * q->prep_rq_fn return values
586 */
587#define BLKPREP_OK 0 /* serve it */
588#define BLKPREP_KILL 1 /* fatal error, kill */
589#define BLKPREP_DEFER 2 /* leave on queue */
590
591extern unsigned long blk_max_low_pfn, blk_max_pfn;
592
593/*
594 * standard bounce addresses:
595 *
596 * BLK_BOUNCE_HIGH : bounce all highmem pages
597 * BLK_BOUNCE_ANY : don't bounce anything
598 * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
599 */
Andi Kleen24728922008-04-21 09:51:05 +0200600
601#if BITS_PER_LONG == 32
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602#define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
Andi Kleen24728922008-04-21 09:51:05 +0200603#else
604#define BLK_BOUNCE_HIGH -1ULL
605#endif
606#define BLK_BOUNCE_ANY (-1ULL)
FUJITA Tomonoribfe17232010-05-31 15:59:03 +0900607#define BLK_BOUNCE_ISA (DMA_BIT_MASK(24))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608
Jens Axboe3d6392c2007-07-09 12:38:05 +0200609/*
610 * default timeout for SG_IO if none specified
611 */
612#define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
Linus Torvaldsf2f1fa72008-12-05 14:49:18 -0800613#define BLK_MIN_SG_TIMEOUT (7 * HZ)
Jens Axboe3d6392c2007-07-09 12:38:05 +0200614
Christoph Lameter2a7326b2007-07-17 04:03:37 -0700615#ifdef CONFIG_BOUNCE
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616extern int init_emergency_isa_pool(void);
Jens Axboe165125e2007-07-24 09:28:11 +0200617extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618#else
619static inline int init_emergency_isa_pool(void)
620{
621 return 0;
622}
Jens Axboe165125e2007-07-24 09:28:11 +0200623static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624{
625}
626#endif /* CONFIG_MMU */
627
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900628struct rq_map_data {
629 struct page **pages;
630 int page_order;
631 int nr_entries;
FUJITA Tomonori56c451f2008-12-18 14:49:37 +0900632 unsigned long offset;
FUJITA Tomonori97ae77a2008-12-18 14:49:38 +0900633 int null_mapped;
FUJITA Tomonoriecb554a2009-07-09 14:46:53 +0200634 int from_user;
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900635};
636
NeilBrown5705f702007-09-25 12:35:59 +0200637struct req_iterator {
638 int i;
639 struct bio *bio;
640};
641
642/* This should not be used directly - use rq_for_each_segment */
Jens Axboe1e428072009-02-23 09:03:10 +0100643#define for_each_bio(_bio) \
644 for (; _bio; _bio = _bio->bi_next)
NeilBrown5705f702007-09-25 12:35:59 +0200645#define __rq_for_each_bio(_bio, rq) \
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646 if ((rq->bio)) \
647 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
648
NeilBrown5705f702007-09-25 12:35:59 +0200649#define rq_for_each_segment(bvl, _rq, _iter) \
650 __rq_for_each_bio(_iter.bio, _rq) \
651 bio_for_each_segment(bvl, _iter.bio, _iter.i)
652
653#define rq_iter_last(rq, _iter) \
654 (_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1)
655
Ilya Loginov2d4dc892009-11-26 09:16:19 +0100656#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
657# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
658#endif
659#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
660extern void rq_flush_dcache_pages(struct request *rq);
661#else
662static inline void rq_flush_dcache_pages(struct request *rq)
663{
664}
665#endif
666
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667extern int blk_register_queue(struct gendisk *disk);
668extern void blk_unregister_queue(struct gendisk *disk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669extern void generic_make_request(struct bio *bio);
FUJITA Tomonori2a4aa302008-04-29 09:54:36 +0200670extern void blk_rq_init(struct request_queue *q, struct request *rq);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671extern void blk_put_request(struct request *);
Jens Axboe165125e2007-07-24 09:28:11 +0200672extern void __blk_put_request(struct request_queue *, struct request *);
Jens Axboe165125e2007-07-24 09:28:11 +0200673extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
Boaz Harrosh79eb63e2009-05-17 18:57:15 +0300674extern struct request *blk_make_request(struct request_queue *, struct bio *,
675 gfp_t);
Jens Axboe165125e2007-07-24 09:28:11 +0200676extern void blk_requeue_request(struct request_queue *, struct request *);
Christoph Hellwig66ac0282010-06-18 16:59:42 +0200677extern void blk_add_request_payload(struct request *rq, struct page *page,
678 unsigned int len);
Kiyoshi Ueda82124d62008-09-18 10:45:38 -0400679extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +0200680extern int blk_lld_busy(struct request_queue *q);
Kiyoshi Uedab0fd2712009-06-11 13:10:16 +0200681extern int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
682 struct bio_set *bs, gfp_t gfp_mask,
683 int (*bio_ctr)(struct bio *, struct bio *, void *),
684 void *data);
685extern void blk_rq_unprep_clone(struct request *rq);
Kiyoshi Ueda82124d62008-09-18 10:45:38 -0400686extern int blk_insert_cloned_request(struct request_queue *q,
687 struct request *rq);
Jens Axboe3cca6dc2011-03-02 11:08:00 -0500688extern void blk_delay_queue(struct request_queue *, unsigned long);
Jens Axboe165125e2007-07-24 09:28:11 +0200689extern void blk_recount_segments(struct request_queue *, struct bio *);
Paolo Bonzini0bfc96c2012-01-12 16:01:28 +0100690extern int scsi_verify_blk_ioctl(struct block_device *, unsigned int);
Paolo Bonzini577ebb32012-01-12 16:01:27 +0100691extern int scsi_cmd_blk_ioctl(struct block_device *, fmode_t,
692 unsigned int, void __user *);
Al Viro74f3c8a2007-08-27 15:38:10 -0400693extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
694 unsigned int, void __user *);
Al Viroe915e872008-09-02 17:16:41 -0400695extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
696 struct scsi_ioctl_command __user *);
Andrew Morton3fcfab12006-10-19 23:28:16 -0700697
Christoph Hellwig5a7bbad2011-09-12 12:12:01 +0200698extern void blk_queue_bio(struct request_queue *q, struct bio *bio);
Christoph Hellwig166e1f92011-09-12 12:08:27 +0200699
Andrew Morton3fcfab12006-10-19 23:28:16 -0700700/*
701 * A queue has just exitted congestion. Note this in the global counter of
702 * congested queues, and wake up anyone who was waiting for requests to be
703 * put back.
704 */
Jens Axboe8aa7e842009-07-09 14:52:32 +0200705static inline void blk_clear_queue_congested(struct request_queue *q, int sync)
Andrew Morton3fcfab12006-10-19 23:28:16 -0700706{
Jens Axboe8aa7e842009-07-09 14:52:32 +0200707 clear_bdi_congested(&q->backing_dev_info, sync);
Andrew Morton3fcfab12006-10-19 23:28:16 -0700708}
709
710/*
711 * A queue has just entered congestion. Flag that in the queue's VM-visible
712 * state flags and increment the global gounter of congested queues.
713 */
Jens Axboe8aa7e842009-07-09 14:52:32 +0200714static inline void blk_set_queue_congested(struct request_queue *q, int sync)
Andrew Morton3fcfab12006-10-19 23:28:16 -0700715{
Jens Axboe8aa7e842009-07-09 14:52:32 +0200716 set_bdi_congested(&q->backing_dev_info, sync);
Andrew Morton3fcfab12006-10-19 23:28:16 -0700717}
718
Jens Axboe165125e2007-07-24 09:28:11 +0200719extern void blk_start_queue(struct request_queue *q);
720extern void blk_stop_queue(struct request_queue *q);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721extern void blk_sync_queue(struct request_queue *q);
Jens Axboe165125e2007-07-24 09:28:11 +0200722extern void __blk_stop_queue(struct request_queue *q);
Christoph Hellwig24ecfbe2011-04-18 11:41:33 +0200723extern void __blk_run_queue(struct request_queue *q);
Jens Axboe165125e2007-07-24 09:28:11 +0200724extern void blk_run_queue(struct request_queue *);
Jens Axboec21e6be2011-04-19 13:32:46 +0200725extern void blk_run_queue_async(struct request_queue *q);
FUJITA Tomonoria3bce902008-08-28 16:17:05 +0900726extern int blk_rq_map_user(struct request_queue *, struct request *,
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900727 struct rq_map_data *, void __user *, unsigned long,
728 gfp_t);
Jens Axboe8e5cfc42006-12-19 11:12:46 +0100729extern int blk_rq_unmap_user(struct bio *);
Jens Axboe165125e2007-07-24 09:28:11 +0200730extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
731extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
FUJITA Tomonori152e2832008-08-28 16:17:06 +0900732 struct rq_map_data *, struct sg_iovec *, int,
733 unsigned int, gfp_t);
Jens Axboe165125e2007-07-24 09:28:11 +0200734extern int blk_execute_rq(struct request_queue *, struct gendisk *,
James Bottomley 994ca9a2005-06-20 14:11:09 +0200735 struct request *, int);
Jens Axboe165125e2007-07-24 09:28:11 +0200736extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
Jens Axboe15fc8582006-01-06 10:00:50 +0100737 struct request *, int, rq_end_io_fn *);
Mike Christie6e39b692005-11-11 05:30:24 -0600738
Jens Axboe165125e2007-07-24 09:28:11 +0200739static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740{
741 return bdev->bd_disk->queue;
742}
743
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744/*
Tejun Heo80a761f2009-07-03 17:48:17 +0900745 * blk_rq_pos() : the current sector
746 * blk_rq_bytes() : bytes left in the entire request
747 * blk_rq_cur_bytes() : bytes left in the current segment
748 * blk_rq_err_bytes() : bytes left till the next error boundary
749 * blk_rq_sectors() : sectors left in the entire request
750 * blk_rq_cur_sectors() : sectors left in the current segment
Tejun Heo5efccd12009-04-23 11:05:18 +0900751 */
Tejun Heo5b936292009-05-07 22:24:38 +0900752static inline sector_t blk_rq_pos(const struct request *rq)
753{
Tejun Heoa2dec7b2009-05-07 22:24:44 +0900754 return rq->__sector;
Tejun Heo5b936292009-05-07 22:24:38 +0900755}
756
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900757static inline unsigned int blk_rq_bytes(const struct request *rq)
758{
Tejun Heoa2dec7b2009-05-07 22:24:44 +0900759 return rq->__data_len;
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900760}
761
762static inline int blk_rq_cur_bytes(const struct request *rq)
763{
764 return rq->bio ? bio_cur_bytes(rq->bio) : 0;
765}
Tejun Heo5efccd12009-04-23 11:05:18 +0900766
Tejun Heo80a761f2009-07-03 17:48:17 +0900767extern unsigned int blk_rq_err_bytes(const struct request *rq);
768
Tejun Heo5b936292009-05-07 22:24:38 +0900769static inline unsigned int blk_rq_sectors(const struct request *rq)
770{
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900771 return blk_rq_bytes(rq) >> 9;
Tejun Heo5b936292009-05-07 22:24:38 +0900772}
773
774static inline unsigned int blk_rq_cur_sectors(const struct request *rq)
775{
Tejun Heo2e46e8b2009-05-07 22:24:41 +0900776 return blk_rq_cur_bytes(rq) >> 9;
Tejun Heo5b936292009-05-07 22:24:38 +0900777}
778
Tejun Heo5efccd12009-04-23 11:05:18 +0900779/*
Tejun Heo9934c8c2009-05-08 11:54:16 +0900780 * Request issue related functions.
781 */
782extern struct request *blk_peek_request(struct request_queue *q);
783extern void blk_start_request(struct request *rq);
784extern struct request *blk_fetch_request(struct request_queue *q);
785
786/*
Tejun Heo2e60e022009-04-23 11:05:18 +0900787 * Request completion related functions.
788 *
789 * blk_update_request() completes given number of bytes and updates
790 * the request without completing it.
791 *
Tejun Heof06d9a22009-04-23 11:05:19 +0900792 * blk_end_request() and friends. __blk_end_request() must be called
793 * with the request queue spinlock acquired.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 *
795 * Several drivers define their own end_request and call
Kiyoshi Ueda3bcddea2007-12-11 17:52:28 -0500796 * blk_end_request() for parts of the original function.
797 * This prevents code duplication in drivers.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798 */
Tejun Heo2e60e022009-04-23 11:05:18 +0900799extern bool blk_update_request(struct request *rq, int error,
800 unsigned int nr_bytes);
FUJITA Tomonorib1f74492009-05-11 17:56:09 +0900801extern bool blk_end_request(struct request *rq, int error,
802 unsigned int nr_bytes);
803extern void blk_end_request_all(struct request *rq, int error);
804extern bool blk_end_request_cur(struct request *rq, int error);
Tejun Heo80a761f2009-07-03 17:48:17 +0900805extern bool blk_end_request_err(struct request *rq, int error);
FUJITA Tomonorib1f74492009-05-11 17:56:09 +0900806extern bool __blk_end_request(struct request *rq, int error,
807 unsigned int nr_bytes);
808extern void __blk_end_request_all(struct request *rq, int error);
809extern bool __blk_end_request_cur(struct request *rq, int error);
Tejun Heo80a761f2009-07-03 17:48:17 +0900810extern bool __blk_end_request_err(struct request *rq, int error);
Tejun Heo2e60e022009-04-23 11:05:18 +0900811
Jens Axboeff856ba2006-01-09 16:02:34 +0100812extern void blk_complete_request(struct request *);
Jens Axboe242f9dc2008-09-14 05:55:09 -0700813extern void __blk_complete_request(struct request *);
814extern void blk_abort_request(struct request *);
Mike Anderson11914a52008-09-13 20:31:27 +0200815extern void blk_abort_queue(struct request_queue *);
James Bottomley28018c22010-07-01 19:49:17 +0900816extern void blk_unprep_request(struct request *);
Jens Axboeff856ba2006-01-09 16:02:34 +0100817
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700819 * Access functions for manipulating queue properties
820 */
Jens Axboe165125e2007-07-24 09:28:11 +0200821extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
Christoph Lameter19460892005-06-23 00:08:19 -0700822 spinlock_t *lock, int node_id);
Jens Axboe165125e2007-07-24 09:28:11 +0200823extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
Mike Snitzer01effb02010-05-11 08:57:42 +0200824extern struct request_queue *blk_init_allocated_queue(struct request_queue *,
825 request_fn_proc *, spinlock_t *);
Jens Axboe165125e2007-07-24 09:28:11 +0200826extern void blk_cleanup_queue(struct request_queue *);
827extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
828extern void blk_queue_bounce_limit(struct request_queue *, u64);
Mike Snitzer72d4cd92010-12-17 08:34:20 +0100829extern void blk_limits_max_hw_sectors(struct queue_limits *, unsigned int);
Martin K. Petersen086fa5f2010-02-26 00:20:38 -0500830extern void blk_queue_max_hw_sectors(struct request_queue *, unsigned int);
Martin K. Petersen8a783622010-02-26 00:20:39 -0500831extern void blk_queue_max_segments(struct request_queue *, unsigned short);
Jens Axboe165125e2007-07-24 09:28:11 +0200832extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
Christoph Hellwig67efc922009-09-30 13:54:20 +0200833extern void blk_queue_max_discard_sectors(struct request_queue *q,
834 unsigned int max_discard_sectors);
Martin K. Petersene1defc42009-05-22 17:17:49 -0400835extern void blk_queue_logical_block_size(struct request_queue *, unsigned short);
Martin K. Petersen892b6f92010-10-13 21:18:03 +0200836extern void blk_queue_physical_block_size(struct request_queue *, unsigned int);
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400837extern void blk_queue_alignment_offset(struct request_queue *q,
838 unsigned int alignment);
Martin K. Petersen7c958e32009-07-31 11:49:11 -0400839extern void blk_limits_io_min(struct queue_limits *limits, unsigned int min);
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400840extern void blk_queue_io_min(struct request_queue *q, unsigned int min);
Martin K. Petersen3c5820c2009-09-11 21:54:52 +0200841extern void blk_limits_io_opt(struct queue_limits *limits, unsigned int opt);
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400842extern void blk_queue_io_opt(struct request_queue *q, unsigned int opt);
Martin K. Petersene475bba2009-06-16 08:23:52 +0200843extern void blk_set_default_limits(struct queue_limits *lim);
Martin K. Petersenb1bd0552012-01-11 16:27:11 +0100844extern void blk_set_stacking_limits(struct queue_limits *lim);
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400845extern int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
846 sector_t offset);
Martin K. Petersen17be8c22010-01-11 03:21:49 -0500847extern int bdev_stack_limits(struct queue_limits *t, struct block_device *bdev,
848 sector_t offset);
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400849extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev,
850 sector_t offset);
Jens Axboe165125e2007-07-24 09:28:11 +0200851extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
Tejun Heoe3790c72008-03-04 11:18:17 +0100852extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
FUJITA Tomonori27f82212008-07-04 09:30:03 +0200853extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
Tejun Heo2fb98e82008-02-19 11:36:53 +0100854extern int blk_queue_dma_drain(struct request_queue *q,
855 dma_drain_needed_fn *dma_drain_needed,
856 void *buf, unsigned int size);
Kiyoshi Uedaef9e3fa2008-10-01 16:12:15 +0200857extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
Jens Axboe165125e2007-07-24 09:28:11 +0200858extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
859extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
James Bottomley28018c22010-07-01 19:49:17 +0900860extern void blk_queue_unprep_rq(struct request_queue *, unprep_rq_fn *ufn);
Jens Axboe165125e2007-07-24 09:28:11 +0200861extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *);
862extern void blk_queue_dma_alignment(struct request_queue *, int);
James Bottomley11c3e682007-12-31 16:37:00 -0600863extern void blk_queue_update_dma_alignment(struct request_queue *, int);
Jens Axboe165125e2007-07-24 09:28:11 +0200864extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
Jens Axboe242f9dc2008-09-14 05:55:09 -0700865extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
866extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
Tejun Heo4913efe2010-09-03 11:56:16 +0200867extern void blk_queue_flush(struct request_queue *q, unsigned int flush);
shaohua.li@intel.comf3876932011-05-06 11:34:32 -0600868extern void blk_queue_flush_queueable(struct request_queue *q, bool queueable);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870
Jens Axboe165125e2007-07-24 09:28:11 +0200871extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872extern void blk_dump_rq_flags(struct request *, char *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873extern long nr_blockdev_pages(void);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874
Tejun Heo09ac46c2011-12-14 00:33:38 +0100875bool __must_check blk_get_queue(struct request_queue *);
Jens Axboe165125e2007-07-24 09:28:11 +0200876struct request_queue *blk_alloc_queue(gfp_t);
877struct request_queue *blk_alloc_queue_node(gfp_t, int);
878extern void blk_put_queue(struct request_queue *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879
Shaohua Li316cc672011-07-08 08:19:21 +0200880/*
Suresh Jayaraman75df7132011-09-21 10:00:16 +0200881 * blk_plug permits building a queue of related requests by holding the I/O
882 * fragments for a short period. This allows merging of sequential requests
883 * into single larger request. As the requests are moved from a per-task list to
884 * the device's request_queue in a batch, this results in improved scalability
885 * as the lock contention for request_queue lock is reduced.
886 *
887 * It is ok not to disable preemption when adding the request to the plug list
888 * or when attempting a merge, because blk_schedule_flush_list() will only flush
889 * the plug list when the task sleeps by itself. For details, please see
890 * schedule() where blk_schedule_flush_plug() is called.
Shaohua Li316cc672011-07-08 08:19:21 +0200891 */
Jens Axboe73c10102011-03-08 13:19:51 +0100892struct blk_plug {
Suresh Jayaraman75df7132011-09-21 10:00:16 +0200893 unsigned long magic; /* detect uninitialized use-cases */
894 struct list_head list; /* requests */
895 struct list_head cb_list; /* md requires an unplug callback */
896 unsigned int should_sort; /* list to be sorted before flushing? */
Jens Axboe73c10102011-03-08 13:19:51 +0100897};
Shaohua Li55c022b2011-07-08 08:19:20 +0200898#define BLK_MAX_REQUEST_COUNT 16
899
NeilBrown048c9372011-04-18 09:52:22 +0200900struct blk_plug_cb {
901 struct list_head list;
902 void (*callback)(struct blk_plug_cb *);
903};
Jens Axboe73c10102011-03-08 13:19:51 +0100904
905extern void blk_start_plug(struct blk_plug *);
906extern void blk_finish_plug(struct blk_plug *);
Jens Axboef6603782011-04-15 15:49:07 +0200907extern void blk_flush_plug_list(struct blk_plug *, bool);
Jens Axboe73c10102011-03-08 13:19:51 +0100908
909static inline void blk_flush_plug(struct task_struct *tsk)
910{
911 struct blk_plug *plug = tsk->plug;
912
Christoph Hellwig88b996c2011-04-15 15:20:10 +0200913 if (plug)
Jens Axboea237c1c2011-04-16 13:27:55 +0200914 blk_flush_plug_list(plug, false);
915}
916
917static inline void blk_schedule_flush_plug(struct task_struct *tsk)
918{
919 struct blk_plug *plug = tsk->plug;
920
921 if (plug)
Jens Axboef6603782011-04-15 15:49:07 +0200922 blk_flush_plug_list(plug, true);
Jens Axboe73c10102011-03-08 13:19:51 +0100923}
924
925static inline bool blk_needs_flush_plug(struct task_struct *tsk)
926{
927 struct blk_plug *plug = tsk->plug;
928
NeilBrown048c9372011-04-18 09:52:22 +0200929 return plug && (!list_empty(&plug->list) || !list_empty(&plug->cb_list));
Jens Axboe73c10102011-03-08 13:19:51 +0100930}
931
Linus Torvalds1da177e2005-04-16 15:20:36 -0700932/*
933 * tag stuff
934 */
Jens Axboe4aff5e22006-08-10 08:44:47 +0200935#define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED)
Jens Axboe165125e2007-07-24 09:28:11 +0200936extern int blk_queue_start_tag(struct request_queue *, struct request *);
937extern struct request *blk_queue_find_tag(struct request_queue *, int);
938extern void blk_queue_end_tag(struct request_queue *, struct request *);
939extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *);
940extern void blk_queue_free_tags(struct request_queue *);
941extern int blk_queue_resize_tags(struct request_queue *, int);
942extern void blk_queue_invalidate_tags(struct request_queue *);
James Bottomley492dfb42006-08-30 15:48:45 -0400943extern struct blk_queue_tag *blk_init_tags(int);
944extern void blk_free_tags(struct blk_queue_tag *);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945
David C Somayajuluf583f492006-10-04 08:27:25 +0200946static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
947 int tag)
948{
949 if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
950 return NULL;
951 return bqt->tag_index[tag];
952}
Christoph Hellwigdd3932e2010-09-16 20:51:46 +0200953
954#define BLKDEV_DISCARD_SECURE 0x01 /* secure discard */
955
956extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *);
Dmitry Monakhovfbd9b092010-04-28 17:55:06 +0400957extern int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
958 sector_t nr_sects, gfp_t gfp_mask, unsigned long flags);
Dmitry Monakhov3f14d792010-04-28 17:55:09 +0400959extern int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
Christoph Hellwigdd3932e2010-09-16 20:51:46 +0200960 sector_t nr_sects, gfp_t gfp_mask);
Christoph Hellwig2cf6d262010-08-18 05:29:10 -0400961static inline int sb_issue_discard(struct super_block *sb, sector_t block,
962 sector_t nr_blocks, gfp_t gfp_mask, unsigned long flags)
David Woodhousefb2dce82008-08-05 18:01:53 +0100963{
Christoph Hellwig2cf6d262010-08-18 05:29:10 -0400964 return blkdev_issue_discard(sb->s_bdev, block << (sb->s_blocksize_bits - 9),
965 nr_blocks << (sb->s_blocksize_bits - 9),
966 gfp_mask, flags);
David Woodhousefb2dce82008-08-05 18:01:53 +0100967}
Lukas Czernere6fa0be2010-10-27 21:30:04 -0400968static inline int sb_issue_zeroout(struct super_block *sb, sector_t block,
Theodore Ts'oa107e5a2010-10-27 23:44:47 -0400969 sector_t nr_blocks, gfp_t gfp_mask)
Lukas Czernere6fa0be2010-10-27 21:30:04 -0400970{
971 return blkdev_issue_zeroout(sb->s_bdev,
972 block << (sb->s_blocksize_bits - 9),
973 nr_blocks << (sb->s_blocksize_bits - 9),
Theodore Ts'oa107e5a2010-10-27 23:44:47 -0400974 gfp_mask);
Lukas Czernere6fa0be2010-10-27 21:30:04 -0400975}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976
Jens Axboe018e0442009-06-26 16:27:10 +0200977extern int blk_verify_command(unsigned char *cmd, fmode_t has_write_perm);
Adel Gadllah0b07de82008-06-26 13:48:27 +0200978
Martin K. Peterseneb28d312010-02-26 00:20:37 -0500979enum blk_default_limits {
980 BLK_MAX_SEGMENTS = 128,
981 BLK_SAFE_MAX_SECTORS = 255,
982 BLK_DEF_MAX_SECTORS = 1024,
983 BLK_MAX_SEGMENT_SIZE = 65536,
984 BLK_SEG_BOUNDARY_MASK = 0xFFFFFFFFUL,
985};
Milan Broz0e435ac2008-12-03 12:55:08 +0100986
Linus Torvalds1da177e2005-04-16 15:20:36 -0700987#define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
988
Martin K. Petersenae03bf62009-05-22 17:17:50 -0400989static inline unsigned long queue_bounce_pfn(struct request_queue *q)
990{
Martin K. Petersen025146e2009-05-22 17:17:51 -0400991 return q->limits.bounce_pfn;
Martin K. Petersenae03bf62009-05-22 17:17:50 -0400992}
993
994static inline unsigned long queue_segment_boundary(struct request_queue *q)
995{
Martin K. Petersen025146e2009-05-22 17:17:51 -0400996 return q->limits.seg_boundary_mask;
Martin K. Petersenae03bf62009-05-22 17:17:50 -0400997}
998
999static inline unsigned int queue_max_sectors(struct request_queue *q)
1000{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001001 return q->limits.max_sectors;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001002}
1003
1004static inline unsigned int queue_max_hw_sectors(struct request_queue *q)
1005{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001006 return q->limits.max_hw_sectors;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001007}
1008
Martin K. Petersen8a783622010-02-26 00:20:39 -05001009static inline unsigned short queue_max_segments(struct request_queue *q)
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001010{
Martin K. Petersen8a783622010-02-26 00:20:39 -05001011 return q->limits.max_segments;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001012}
1013
1014static inline unsigned int queue_max_segment_size(struct request_queue *q)
1015{
Martin K. Petersen025146e2009-05-22 17:17:51 -04001016 return q->limits.max_segment_size;
Martin K. Petersenae03bf62009-05-22 17:17:50 -04001017}
1018
Martin K. Petersene1defc42009-05-22 17:17:49 -04001019static inline unsigned short queue_logical_block_size(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001020{
1021 int retval = 512;
1022
Martin K. Petersen025146e2009-05-22 17:17:51 -04001023 if (q && q->limits.logical_block_size)
1024 retval = q->limits.logical_block_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001025
1026 return retval;
1027}
1028
Martin K. Petersene1defc42009-05-22 17:17:49 -04001029static inline unsigned short bdev_logical_block_size(struct block_device *bdev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001030{
Martin K. Petersene1defc42009-05-22 17:17:49 -04001031 return queue_logical_block_size(bdev_get_queue(bdev));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001032}
1033
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001034static inline unsigned int queue_physical_block_size(struct request_queue *q)
1035{
1036 return q->limits.physical_block_size;
1037}
1038
Martin K. Petersen892b6f92010-10-13 21:18:03 +02001039static inline unsigned int bdev_physical_block_size(struct block_device *bdev)
Martin K. Petersenac481c22009-10-03 20:52:01 +02001040{
1041 return queue_physical_block_size(bdev_get_queue(bdev));
1042}
1043
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001044static inline unsigned int queue_io_min(struct request_queue *q)
1045{
1046 return q->limits.io_min;
1047}
1048
Martin K. Petersenac481c22009-10-03 20:52:01 +02001049static inline int bdev_io_min(struct block_device *bdev)
1050{
1051 return queue_io_min(bdev_get_queue(bdev));
1052}
1053
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001054static inline unsigned int queue_io_opt(struct request_queue *q)
1055{
1056 return q->limits.io_opt;
1057}
1058
Martin K. Petersenac481c22009-10-03 20:52:01 +02001059static inline int bdev_io_opt(struct block_device *bdev)
1060{
1061 return queue_io_opt(bdev_get_queue(bdev));
1062}
1063
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001064static inline int queue_alignment_offset(struct request_queue *q)
1065{
Martin K. Petersenac481c22009-10-03 20:52:01 +02001066 if (q->limits.misaligned)
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001067 return -1;
1068
Martin K. Petersenac481c22009-10-03 20:52:01 +02001069 return q->limits.alignment_offset;
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001070}
1071
Martin K. Petersene03a72e2010-01-11 03:21:51 -05001072static inline int queue_limit_alignment_offset(struct queue_limits *lim, sector_t sector)
Martin K. Petersen81744ee2009-12-29 08:35:35 +01001073{
1074 unsigned int granularity = max(lim->physical_block_size, lim->io_min);
Martin K. Petersene03a72e2010-01-11 03:21:51 -05001075 unsigned int alignment = (sector << 9) & (granularity - 1);
Martin K. Petersen81744ee2009-12-29 08:35:35 +01001076
Martin K. Petersene03a72e2010-01-11 03:21:51 -05001077 return (granularity + lim->alignment_offset - alignment)
1078 & (granularity - 1);
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001079}
1080
Martin K. Petersenac481c22009-10-03 20:52:01 +02001081static inline int bdev_alignment_offset(struct block_device *bdev)
1082{
1083 struct request_queue *q = bdev_get_queue(bdev);
1084
1085 if (q->limits.misaligned)
1086 return -1;
1087
1088 if (bdev != bdev->bd_contains)
1089 return bdev->bd_part->alignment_offset;
1090
1091 return q->limits.alignment_offset;
1092}
1093
Martin K. Petersen86b37282009-11-10 11:50:21 +01001094static inline int queue_discard_alignment(struct request_queue *q)
1095{
1096 if (q->limits.discard_misaligned)
1097 return -1;
1098
1099 return q->limits.discard_alignment;
1100}
1101
Martin K. Petersene03a72e2010-01-11 03:21:51 -05001102static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
Martin K. Petersen86b37282009-11-10 11:50:21 +01001103{
Martin K. Petersendd3d1452010-01-11 03:21:48 -05001104 unsigned int alignment = (sector << 9) & (lim->discard_granularity - 1);
1105
Martin K. Petersena934a002011-05-18 10:37:35 +02001106 if (!lim->max_discard_sectors)
1107 return 0;
1108
Martin K. Petersendd3d1452010-01-11 03:21:48 -05001109 return (lim->discard_granularity + lim->discard_alignment - alignment)
1110 & (lim->discard_granularity - 1);
Martin K. Petersen86b37282009-11-10 11:50:21 +01001111}
1112
Martin K. Petersen98262f22009-12-03 09:24:48 +01001113static inline unsigned int queue_discard_zeroes_data(struct request_queue *q)
1114{
Martin K. Petersena934a002011-05-18 10:37:35 +02001115 if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1)
Martin K. Petersen98262f22009-12-03 09:24:48 +01001116 return 1;
1117
1118 return 0;
1119}
1120
1121static inline unsigned int bdev_discard_zeroes_data(struct block_device *bdev)
1122{
1123 return queue_discard_zeroes_data(bdev_get_queue(bdev));
1124}
1125
Jens Axboe165125e2007-07-24 09:28:11 +02001126static inline int queue_dma_alignment(struct request_queue *q)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001127{
Pete Wyckoff482eb682008-01-01 10:23:02 -05001128 return q ? q->dma_alignment : 511;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001129}
1130
Namhyung Kim14417792010-09-15 13:08:27 +02001131static inline int blk_rq_aligned(struct request_queue *q, unsigned long addr,
FUJITA Tomonori87904072008-08-28 15:05:58 +09001132 unsigned int len)
1133{
1134 unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
Namhyung Kim14417792010-09-15 13:08:27 +02001135 return !(addr & alignment) && !(len & alignment);
FUJITA Tomonori87904072008-08-28 15:05:58 +09001136}
1137
Linus Torvalds1da177e2005-04-16 15:20:36 -07001138/* assumes size > 256 */
1139static inline unsigned int blksize_bits(unsigned int size)
1140{
1141 unsigned int bits = 8;
1142 do {
1143 bits++;
1144 size >>= 1;
1145 } while (size > 256);
1146 return bits;
1147}
1148
Adrian Bunk2befb9e2005-09-10 00:27:17 -07001149static inline unsigned int block_size(struct block_device *bdev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150{
1151 return bdev->bd_block_size;
1152}
1153
shaohua.li@intel.comf3876932011-05-06 11:34:32 -06001154static inline bool queue_flush_queueable(struct request_queue *q)
1155{
1156 return !q->flush_not_queueable;
1157}
1158
Linus Torvalds1da177e2005-04-16 15:20:36 -07001159typedef struct {struct page *v;} Sector;
1160
1161unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
1162
1163static inline void put_dev_sector(Sector p)
1164{
1165 page_cache_release(p.v);
1166}
1167
1168struct work_struct;
Jens Axboe18887ad2008-07-28 13:08:45 +02001169int kblockd_schedule_work(struct request_queue *q, struct work_struct *work);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001170
Divyesh Shah91952912010-04-01 15:01:41 -07001171#ifdef CONFIG_BLK_CGROUP
Jens Axboe28f41972010-06-01 12:23:18 +02001172/*
1173 * This should not be using sched_clock(). A real patch is in progress
1174 * to fix this up, until that is in place we need to disable preemption
1175 * around sched_clock() in this function and set_io_start_time_ns().
1176 */
Divyesh Shah91952912010-04-01 15:01:41 -07001177static inline void set_start_time_ns(struct request *req)
1178{
Jens Axboe28f41972010-06-01 12:23:18 +02001179 preempt_disable();
Divyesh Shah91952912010-04-01 15:01:41 -07001180 req->start_time_ns = sched_clock();
Jens Axboe28f41972010-06-01 12:23:18 +02001181 preempt_enable();
Divyesh Shah91952912010-04-01 15:01:41 -07001182}
1183
1184static inline void set_io_start_time_ns(struct request *req)
1185{
Jens Axboe28f41972010-06-01 12:23:18 +02001186 preempt_disable();
Divyesh Shah91952912010-04-01 15:01:41 -07001187 req->io_start_time_ns = sched_clock();
Jens Axboe28f41972010-06-01 12:23:18 +02001188 preempt_enable();
Divyesh Shah91952912010-04-01 15:01:41 -07001189}
Divyesh Shah84c124d2010-04-09 08:31:19 +02001190
1191static inline uint64_t rq_start_time_ns(struct request *req)
1192{
1193 return req->start_time_ns;
1194}
1195
1196static inline uint64_t rq_io_start_time_ns(struct request *req)
1197{
1198 return req->io_start_time_ns;
1199}
Divyesh Shah91952912010-04-01 15:01:41 -07001200#else
1201static inline void set_start_time_ns(struct request *req) {}
1202static inline void set_io_start_time_ns(struct request *req) {}
Divyesh Shah84c124d2010-04-09 08:31:19 +02001203static inline uint64_t rq_start_time_ns(struct request *req)
1204{
1205 return 0;
1206}
1207static inline uint64_t rq_io_start_time_ns(struct request *req)
1208{
1209 return 0;
1210}
Divyesh Shah91952912010-04-01 15:01:41 -07001211#endif
1212
Linus Torvalds1da177e2005-04-16 15:20:36 -07001213#define MODULE_ALIAS_BLOCKDEV(major,minor) \
1214 MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
1215#define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
1216 MODULE_ALIAS("block-major-" __stringify(major) "-*")
1217
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001218#if defined(CONFIG_BLK_DEV_INTEGRITY)
1219
Jens Axboeb24498d2008-06-27 09:12:09 +02001220#define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */
1221#define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001222
1223struct blk_integrity_exchg {
1224 void *prot_buf;
1225 void *data_buf;
1226 sector_t sector;
1227 unsigned int data_size;
1228 unsigned short sector_size;
1229 const char *disk_name;
1230};
1231
1232typedef void (integrity_gen_fn) (struct blk_integrity_exchg *);
1233typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *);
1234typedef void (integrity_set_tag_fn) (void *, void *, unsigned int);
1235typedef void (integrity_get_tag_fn) (void *, void *, unsigned int);
1236
1237struct blk_integrity {
1238 integrity_gen_fn *generate_fn;
1239 integrity_vrfy_fn *verify_fn;
1240 integrity_set_tag_fn *set_tag_fn;
1241 integrity_get_tag_fn *get_tag_fn;
1242
1243 unsigned short flags;
1244 unsigned short tuple_size;
1245 unsigned short sector_size;
1246 unsigned short tag_size;
1247
1248 const char *name;
1249
1250 struct kobject kobj;
1251};
1252
Mike Snitzera63a5cf2011-04-01 21:02:31 +02001253extern bool blk_integrity_is_initialized(struct gendisk *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001254extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
1255extern void blk_integrity_unregister(struct gendisk *);
Martin K. Petersenad7fce92008-10-01 03:38:39 -04001256extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
Martin K. Petersen13f05c82010-09-10 20:50:10 +02001257extern int blk_rq_map_integrity_sg(struct request_queue *, struct bio *,
1258 struct scatterlist *);
1259extern int blk_rq_count_integrity_sg(struct request_queue *, struct bio *);
1260extern int blk_integrity_merge_rq(struct request_queue *, struct request *,
1261 struct request *);
1262extern int blk_integrity_merge_bio(struct request_queue *, struct request *,
1263 struct bio *);
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001264
Jens Axboeb04accc2008-10-02 12:53:22 +02001265static inline
1266struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
1267{
1268 return bdev->bd_disk->integrity;
1269}
1270
Martin K. Petersenb02739b2008-10-02 18:47:49 +02001271static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1272{
1273 return disk->integrity;
1274}
1275
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001276static inline int blk_integrity_rq(struct request *rq)
1277{
Martin K. Petersend442cc42008-07-16 16:09:06 -04001278 if (rq->bio == NULL)
1279 return 0;
1280
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001281 return bio_integrity(rq->bio);
1282}
1283
Martin K. Petersen13f05c82010-09-10 20:50:10 +02001284static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1285 unsigned int segs)
1286{
1287 q->limits.max_integrity_segments = segs;
1288}
1289
1290static inline unsigned short
1291queue_max_integrity_segments(struct request_queue *q)
1292{
1293 return q->limits.max_integrity_segments;
1294}
1295
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001296#else /* CONFIG_BLK_DEV_INTEGRITY */
1297
Stephen Rothwellfd832402012-01-12 09:17:30 +01001298struct bio;
1299struct block_device;
1300struct gendisk;
1301struct blk_integrity;
1302
1303static inline int blk_integrity_rq(struct request *rq)
1304{
1305 return 0;
1306}
1307static inline int blk_rq_count_integrity_sg(struct request_queue *q,
1308 struct bio *b)
1309{
1310 return 0;
1311}
1312static inline int blk_rq_map_integrity_sg(struct request_queue *q,
1313 struct bio *b,
1314 struct scatterlist *s)
1315{
1316 return 0;
1317}
1318static inline struct blk_integrity *bdev_get_integrity(struct block_device *b)
1319{
1320 return 0;
1321}
1322static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
1323{
1324 return NULL;
1325}
1326static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b)
1327{
1328 return 0;
1329}
1330static inline int blk_integrity_register(struct gendisk *d,
1331 struct blk_integrity *b)
1332{
1333 return 0;
1334}
1335static inline void blk_integrity_unregister(struct gendisk *d)
1336{
1337}
1338static inline void blk_queue_max_integrity_segments(struct request_queue *q,
1339 unsigned int segs)
1340{
1341}
1342static inline unsigned short queue_max_integrity_segments(struct request_queue *q)
1343{
1344 return 0;
1345}
1346static inline int blk_integrity_merge_rq(struct request_queue *rq,
1347 struct request *r1,
1348 struct request *r2)
1349{
1350 return 0;
1351}
1352static inline int blk_integrity_merge_bio(struct request_queue *rq,
1353 struct request *r,
1354 struct bio *b)
1355{
1356 return 0;
1357}
1358static inline bool blk_integrity_is_initialized(struct gendisk *g)
1359{
1360 return 0;
1361}
Martin K. Petersen7ba1ba12008-06-30 20:04:41 +02001362
1363#endif /* CONFIG_BLK_DEV_INTEGRITY */
1364
Al Viro08f85852007-10-08 13:26:20 -04001365struct block_device_operations {
Al Virod4430d62008-03-02 09:09:22 -05001366 int (*open) (struct block_device *, fmode_t);
1367 int (*release) (struct gendisk *, fmode_t);
Al Virod4430d62008-03-02 09:09:22 -05001368 int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
1369 int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
Al Viro08f85852007-10-08 13:26:20 -04001370 int (*direct_access) (struct block_device *, sector_t,
1371 void **, unsigned long *);
Tejun Heo77ea8872010-12-08 20:57:37 +01001372 unsigned int (*check_events) (struct gendisk *disk,
1373 unsigned int clearing);
1374 /* ->media_changed() is DEPRECATED, use ->check_events() instead */
Al Viro08f85852007-10-08 13:26:20 -04001375 int (*media_changed) (struct gendisk *);
Tejun Heoc3e33e02010-05-15 20:09:29 +02001376 void (*unlock_native_capacity) (struct gendisk *);
Al Viro08f85852007-10-08 13:26:20 -04001377 int (*revalidate_disk) (struct gendisk *);
1378 int (*getgeo)(struct block_device *, struct hd_geometry *);
Nitin Guptab3a27d02010-05-17 11:02:43 +05301379 /* this callback is with swap_lock and sometimes page table lock held */
1380 void (*swap_slot_free_notify) (struct block_device *, unsigned long);
Al Viro08f85852007-10-08 13:26:20 -04001381 struct module *owner;
1382};
1383
Al Viro633a08b2007-08-29 20:34:12 -04001384extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
1385 unsigned long);
David Howells93614012006-09-30 20:45:40 +02001386#else /* CONFIG_BLOCK */
1387/*
1388 * stubs for when the block layer is configured out
1389 */
1390#define buffer_heads_over_limit 0
1391
David Howells93614012006-09-30 20:45:40 +02001392static inline long nr_blockdev_pages(void)
1393{
1394 return 0;
1395}
1396
Jens Axboe1f940bd2011-03-11 20:17:08 +01001397struct blk_plug {
1398};
1399
1400static inline void blk_start_plug(struct blk_plug *plug)
Jens Axboe73c10102011-03-08 13:19:51 +01001401{
1402}
1403
Jens Axboe1f940bd2011-03-11 20:17:08 +01001404static inline void blk_finish_plug(struct blk_plug *plug)
Jens Axboe73c10102011-03-08 13:19:51 +01001405{
1406}
1407
Jens Axboe1f940bd2011-03-11 20:17:08 +01001408static inline void blk_flush_plug(struct task_struct *task)
Jens Axboe73c10102011-03-08 13:19:51 +01001409{
1410}
1411
Jens Axboea237c1c2011-04-16 13:27:55 +02001412static inline void blk_schedule_flush_plug(struct task_struct *task)
1413{
1414}
1415
1416
Jens Axboe73c10102011-03-08 13:19:51 +01001417static inline bool blk_needs_flush_plug(struct task_struct *tsk)
1418{
1419 return false;
1420}
1421
David Howells93614012006-09-30 20:45:40 +02001422#endif /* CONFIG_BLOCK */
1423
Linus Torvalds1da177e2005-04-16 15:20:36 -07001424#endif