Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 3 | * Copyright (C) 1994, Karl Keyte: Added support for disk statistics |
| 4 | * Elevator latency, (C) 2000 Andrea Arcangeli <andrea@suse.de> SuSE |
| 5 | * Queue request tables / lock, selectable elevator, Jens Axboe <axboe@suse.de> |
Jens Axboe | 6728cb0 | 2008-01-31 13:03:55 +0100 | [diff] [blame] | 6 | * kernel-doc documentation started by NeilBrown <neilb@cse.unsw.edu.au> |
| 7 | * - July2000 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | * bio rewrite, highmem i/o, etc, Jens Axboe <axboe@suse.de> - may 2001 |
| 9 | */ |
| 10 | |
| 11 | /* |
| 12 | * This handles all read/write requests to block devices |
| 13 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #include <linux/kernel.h> |
| 15 | #include <linux/module.h> |
| 16 | #include <linux/backing-dev.h> |
| 17 | #include <linux/bio.h> |
| 18 | #include <linux/blkdev.h> |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 19 | #include <linux/blk-mq.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <linux/highmem.h> |
| 21 | #include <linux/mm.h> |
| 22 | #include <linux/kernel_stat.h> |
| 23 | #include <linux/string.h> |
| 24 | #include <linux/init.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | #include <linux/completion.h> |
| 26 | #include <linux/slab.h> |
| 27 | #include <linux/swap.h> |
| 28 | #include <linux/writeback.h> |
Andrew Morton | faccbd4b | 2006-12-10 02:19:35 -0800 | [diff] [blame] | 29 | #include <linux/task_io_accounting_ops.h> |
Akinobu Mita | c17bb49 | 2006-12-08 02:39:46 -0800 | [diff] [blame] | 30 | #include <linux/fault-inject.h> |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 31 | #include <linux/list_sort.h> |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 32 | #include <linux/delay.h> |
Tejun Heo | aaf7c68 | 2012-04-19 16:29:22 -0700 | [diff] [blame] | 33 | #include <linux/ratelimit.h> |
Lin Ming | 6c95466 | 2013-03-23 11:42:26 +0800 | [diff] [blame] | 34 | #include <linux/pm_runtime.h> |
Tejun Heo | eea8f41 | 2015-05-22 17:13:17 -0400 | [diff] [blame] | 35 | #include <linux/blk-cgroup.h> |
Li Zefan | 5578213 | 2009-06-09 13:43:05 +0800 | [diff] [blame] | 36 | |
| 37 | #define CREATE_TRACE_POINTS |
| 38 | #include <trace/events/block.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | |
Jens Axboe | 8324aa9 | 2008-01-29 14:51:59 +0100 | [diff] [blame] | 40 | #include "blk.h" |
Ming Lei | 43a5e4e | 2013-12-26 21:31:35 +0800 | [diff] [blame] | 41 | #include "blk-mq.h" |
Jens Axboe | 8324aa9 | 2008-01-29 14:51:59 +0100 | [diff] [blame] | 42 | |
Mike Snitzer | d07335e | 2010-11-16 12:52:38 +0100 | [diff] [blame] | 43 | EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_remap); |
Jun'ichi Nomura | b0da3f0 | 2009-10-01 21:16:13 +0200 | [diff] [blame] | 44 | EXPORT_TRACEPOINT_SYMBOL_GPL(block_rq_remap); |
Linus Torvalds | 0a82a8d | 2013-04-18 09:00:26 -0700 | [diff] [blame] | 45 | EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_complete); |
Keith Busch | 3291fa5 | 2014-04-28 12:30:52 -0600 | [diff] [blame] | 46 | EXPORT_TRACEPOINT_SYMBOL_GPL(block_split); |
NeilBrown | cbae8d4 | 2012-12-14 20:49:27 +0100 | [diff] [blame] | 47 | EXPORT_TRACEPOINT_SYMBOL_GPL(block_unplug); |
Ingo Molnar | 0bfc245 | 2008-11-26 11:59:56 +0100 | [diff] [blame] | 48 | |
Tejun Heo | a73f730 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 49 | DEFINE_IDA(blk_queue_ida); |
| 50 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | /* |
| 52 | * For the allocated request tables |
| 53 | */ |
Wei Tang | d674d41 | 2015-11-24 09:58:45 +0800 | [diff] [blame] | 54 | struct kmem_cache *request_cachep; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | |
| 56 | /* |
| 57 | * For queue allocation |
| 58 | */ |
Jens Axboe | 6728cb0 | 2008-01-31 13:03:55 +0100 | [diff] [blame] | 59 | struct kmem_cache *blk_requestq_cachep; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | |
| 61 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 62 | * Controlling structure to kblockd |
| 63 | */ |
Jens Axboe | ff856ba | 2006-01-09 16:02:34 +0100 | [diff] [blame] | 64 | static struct workqueue_struct *kblockd_workqueue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | |
Tejun Heo | d40f75a | 2015-05-22 17:13:42 -0400 | [diff] [blame] | 66 | static void blk_clear_congested(struct request_list *rl, int sync) |
| 67 | { |
Tejun Heo | d40f75a | 2015-05-22 17:13:42 -0400 | [diff] [blame] | 68 | #ifdef CONFIG_CGROUP_WRITEBACK |
| 69 | clear_wb_congested(rl->blkg->wb_congested, sync); |
| 70 | #else |
Tejun Heo | 482cf79 | 2015-05-22 17:13:43 -0400 | [diff] [blame] | 71 | /* |
| 72 | * If !CGROUP_WRITEBACK, all blkg's map to bdi->wb and we shouldn't |
| 73 | * flip its congestion state for events on other blkcgs. |
| 74 | */ |
| 75 | if (rl == &rl->q->root_rl) |
| 76 | clear_wb_congested(rl->q->backing_dev_info.wb.congested, sync); |
Tejun Heo | d40f75a | 2015-05-22 17:13:42 -0400 | [diff] [blame] | 77 | #endif |
| 78 | } |
| 79 | |
| 80 | static void blk_set_congested(struct request_list *rl, int sync) |
| 81 | { |
Tejun Heo | d40f75a | 2015-05-22 17:13:42 -0400 | [diff] [blame] | 82 | #ifdef CONFIG_CGROUP_WRITEBACK |
| 83 | set_wb_congested(rl->blkg->wb_congested, sync); |
| 84 | #else |
Tejun Heo | 482cf79 | 2015-05-22 17:13:43 -0400 | [diff] [blame] | 85 | /* see blk_clear_congested() */ |
| 86 | if (rl == &rl->q->root_rl) |
| 87 | set_wb_congested(rl->q->backing_dev_info.wb.congested, sync); |
Tejun Heo | d40f75a | 2015-05-22 17:13:42 -0400 | [diff] [blame] | 88 | #endif |
| 89 | } |
| 90 | |
Jens Axboe | 8324aa9 | 2008-01-29 14:51:59 +0100 | [diff] [blame] | 91 | void blk_queue_congestion_threshold(struct request_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 92 | { |
| 93 | int nr; |
| 94 | |
| 95 | nr = q->nr_requests - (q->nr_requests / 8) + 1; |
| 96 | if (nr > q->nr_requests) |
| 97 | nr = q->nr_requests; |
| 98 | q->nr_congestion_on = nr; |
| 99 | |
| 100 | nr = q->nr_requests - (q->nr_requests / 8) - (q->nr_requests / 16) - 1; |
| 101 | if (nr < 1) |
| 102 | nr = 1; |
| 103 | q->nr_congestion_off = nr; |
| 104 | } |
| 105 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | /** |
| 107 | * blk_get_backing_dev_info - get the address of a queue's backing_dev_info |
| 108 | * @bdev: device |
| 109 | * |
| 110 | * Locates the passed device's request queue and returns the address of its |
Tejun Heo | ff9ea32 | 2014-09-08 08:03:56 +0900 | [diff] [blame] | 111 | * backing_dev_info. This function can only be called if @bdev is opened |
| 112 | * and the return value is never NULL. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 113 | */ |
| 114 | struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev) |
| 115 | { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 116 | struct request_queue *q = bdev_get_queue(bdev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | |
Tejun Heo | ff9ea32 | 2014-09-08 08:03:56 +0900 | [diff] [blame] | 118 | return &q->backing_dev_info; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 120 | EXPORT_SYMBOL(blk_get_backing_dev_info); |
| 121 | |
FUJITA Tomonori | 2a4aa30 | 2008-04-29 09:54:36 +0200 | [diff] [blame] | 122 | void blk_rq_init(struct request_queue *q, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | { |
FUJITA Tomonori | 1afb20f | 2008-04-25 12:26:28 +0200 | [diff] [blame] | 124 | memset(rq, 0, sizeof(*rq)); |
| 125 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 126 | INIT_LIST_HEAD(&rq->queuelist); |
Jens Axboe | 242f9dc | 2008-09-14 05:55:09 -0700 | [diff] [blame] | 127 | INIT_LIST_HEAD(&rq->timeout_list); |
Jens Axboe | c7c22e4 | 2008-09-13 20:26:01 +0200 | [diff] [blame] | 128 | rq->cpu = -1; |
Jens Axboe | 63a7138 | 2008-02-08 12:41:03 +0100 | [diff] [blame] | 129 | rq->q = q; |
Tejun Heo | a2dec7b | 2009-05-07 22:24:44 +0900 | [diff] [blame] | 130 | rq->__sector = (sector_t) -1; |
Jens Axboe | 2e662b6 | 2006-07-13 11:55:04 +0200 | [diff] [blame] | 131 | INIT_HLIST_NODE(&rq->hash); |
| 132 | RB_CLEAR_NODE(&rq->rb_node); |
FUJITA Tomonori | d7e3c32 | 2008-04-29 09:54:39 +0200 | [diff] [blame] | 133 | rq->cmd = rq->__cmd; |
Li Zefan | e2494e1 | 2009-04-02 13:43:26 +0800 | [diff] [blame] | 134 | rq->cmd_len = BLK_MAX_CDB; |
Jens Axboe | 63a7138 | 2008-02-08 12:41:03 +0100 | [diff] [blame] | 135 | rq->tag = -1; |
Tejun Heo | b243ddc | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 136 | rq->start_time = jiffies; |
Divyesh Shah | 9195291 | 2010-04-01 15:01:41 -0700 | [diff] [blame] | 137 | set_start_time_ns(rq); |
Jerome Marchand | 09e099d | 2011-01-05 16:57:38 +0100 | [diff] [blame] | 138 | rq->part = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | } |
FUJITA Tomonori | 2a4aa30 | 2008-04-29 09:54:36 +0200 | [diff] [blame] | 140 | EXPORT_SYMBOL(blk_rq_init); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 141 | |
NeilBrown | 5bb23a6 | 2007-09-27 12:46:13 +0200 | [diff] [blame] | 142 | static void req_bio_endio(struct request *rq, struct bio *bio, |
| 143 | unsigned int nbytes, int error) |
Tejun Heo | 797e7db | 2006-01-06 09:51:03 +0100 | [diff] [blame] | 144 | { |
Mike Snitzer | 78d8e58 | 2015-06-26 10:01:13 -0400 | [diff] [blame] | 145 | if (error) |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 146 | bio->bi_error = error; |
Tejun Heo | 797e7db | 2006-01-06 09:51:03 +0100 | [diff] [blame] | 147 | |
Tejun Heo | 143a87f | 2011-01-25 12:43:52 +0100 | [diff] [blame] | 148 | if (unlikely(rq->cmd_flags & REQ_QUIET)) |
Jens Axboe | b7c44ed | 2015-07-24 12:37:59 -0600 | [diff] [blame] | 149 | bio_set_flag(bio, BIO_QUIET); |
Tejun Heo | 143a87f | 2011-01-25 12:43:52 +0100 | [diff] [blame] | 150 | |
Kent Overstreet | f79ea41 | 2012-09-20 16:38:30 -0700 | [diff] [blame] | 151 | bio_advance(bio, nbytes); |
Tejun Heo | 143a87f | 2011-01-25 12:43:52 +0100 | [diff] [blame] | 152 | |
| 153 | /* don't actually finish bio if it's part of flush sequence */ |
Mike Snitzer | 78d8e58 | 2015-06-26 10:01:13 -0400 | [diff] [blame] | 154 | if (bio->bi_iter.bi_size == 0 && !(rq->cmd_flags & REQ_FLUSH_SEQ)) |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 155 | bio_endio(bio); |
Tejun Heo | 797e7db | 2006-01-06 09:51:03 +0100 | [diff] [blame] | 156 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 157 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | void blk_dump_rq_flags(struct request *rq, char *msg) |
| 159 | { |
| 160 | int bit; |
| 161 | |
Jens Axboe | 5953316 | 2013-05-23 12:25:08 +0200 | [diff] [blame] | 162 | printk(KERN_INFO "%s: dev %s: type=%x, flags=%llx\n", msg, |
Jens Axboe | 4aff5e2 | 2006-08-10 08:44:47 +0200 | [diff] [blame] | 163 | rq->rq_disk ? rq->rq_disk->disk_name : "?", rq->cmd_type, |
Jens Axboe | 5953316 | 2013-05-23 12:25:08 +0200 | [diff] [blame] | 164 | (unsigned long long) rq->cmd_flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | |
Tejun Heo | 83096eb | 2009-05-07 22:24:39 +0900 | [diff] [blame] | 166 | printk(KERN_INFO " sector %llu, nr/cnr %u/%u\n", |
| 167 | (unsigned long long)blk_rq_pos(rq), |
| 168 | blk_rq_sectors(rq), blk_rq_cur_sectors(rq)); |
Jens Axboe | b4f42e2 | 2014-04-10 09:46:28 -0600 | [diff] [blame] | 169 | printk(KERN_INFO " bio %p, biotail %p, len %u\n", |
| 170 | rq->bio, rq->biotail, blk_rq_bytes(rq)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | |
Christoph Hellwig | 33659eb | 2010-08-07 18:17:56 +0200 | [diff] [blame] | 172 | if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { |
Jens Axboe | 6728cb0 | 2008-01-31 13:03:55 +0100 | [diff] [blame] | 173 | printk(KERN_INFO " cdb: "); |
FUJITA Tomonori | d34c87e | 2008-04-29 14:37:52 +0200 | [diff] [blame] | 174 | for (bit = 0; bit < BLK_MAX_CDB; bit++) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 175 | printk("%02x ", rq->cmd[bit]); |
| 176 | printk("\n"); |
| 177 | } |
| 178 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 179 | EXPORT_SYMBOL(blk_dump_rq_flags); |
| 180 | |
Jens Axboe | 3cca6dc | 2011-03-02 11:08:00 -0500 | [diff] [blame] | 181 | static void blk_delay_work(struct work_struct *work) |
Jens Axboe | 6c5e0c4 | 2008-08-01 20:31:32 +0200 | [diff] [blame] | 182 | { |
Jens Axboe | 3cca6dc | 2011-03-02 11:08:00 -0500 | [diff] [blame] | 183 | struct request_queue *q; |
Jens Axboe | 6c5e0c4 | 2008-08-01 20:31:32 +0200 | [diff] [blame] | 184 | |
Jens Axboe | 3cca6dc | 2011-03-02 11:08:00 -0500 | [diff] [blame] | 185 | q = container_of(work, struct request_queue, delay_work.work); |
| 186 | spin_lock_irq(q->queue_lock); |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 187 | __blk_run_queue(q); |
Jens Axboe | 3cca6dc | 2011-03-02 11:08:00 -0500 | [diff] [blame] | 188 | spin_unlock_irq(q->queue_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 189 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 190 | |
| 191 | /** |
Jens Axboe | 3cca6dc | 2011-03-02 11:08:00 -0500 | [diff] [blame] | 192 | * blk_delay_queue - restart queueing after defined interval |
| 193 | * @q: The &struct request_queue in question |
| 194 | * @msecs: Delay in msecs |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 195 | * |
| 196 | * Description: |
Jens Axboe | 3cca6dc | 2011-03-02 11:08:00 -0500 | [diff] [blame] | 197 | * Sometimes queueing needs to be postponed for a little while, to allow |
| 198 | * resources to come back. This function will make sure that queueing is |
Bart Van Assche | 7046057 | 2012-11-28 13:45:56 +0100 | [diff] [blame] | 199 | * restarted around the specified time. Queue lock must be held. |
Jens Axboe | 3cca6dc | 2011-03-02 11:08:00 -0500 | [diff] [blame] | 200 | */ |
| 201 | void blk_delay_queue(struct request_queue *q, unsigned long msecs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 202 | { |
Bart Van Assche | 7046057 | 2012-11-28 13:45:56 +0100 | [diff] [blame] | 203 | if (likely(!blk_queue_dead(q))) |
| 204 | queue_delayed_work(kblockd_workqueue, &q->delay_work, |
| 205 | msecs_to_jiffies(msecs)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | } |
Jens Axboe | 3cca6dc | 2011-03-02 11:08:00 -0500 | [diff] [blame] | 207 | EXPORT_SYMBOL(blk_delay_queue); |
Alan D. Brunelle | 2ad8b1e | 2007-11-07 14:26:56 -0500 | [diff] [blame] | 208 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 209 | /** |
Jens Axboe | 2149141 | 2015-12-28 13:01:22 -0700 | [diff] [blame] | 210 | * blk_start_queue_async - asynchronously restart a previously stopped queue |
| 211 | * @q: The &struct request_queue in question |
| 212 | * |
| 213 | * Description: |
| 214 | * blk_start_queue_async() will clear the stop flag on the queue, and |
| 215 | * ensure that the request_fn for the queue is run from an async |
| 216 | * context. |
| 217 | **/ |
| 218 | void blk_start_queue_async(struct request_queue *q) |
| 219 | { |
| 220 | queue_flag_clear(QUEUE_FLAG_STOPPED, q); |
| 221 | blk_run_queue_async(q); |
| 222 | } |
| 223 | EXPORT_SYMBOL(blk_start_queue_async); |
| 224 | |
| 225 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | * blk_start_queue - restart a previously stopped queue |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 227 | * @q: The &struct request_queue in question |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | * |
| 229 | * Description: |
| 230 | * blk_start_queue() will clear the stop flag on the queue, and call |
| 231 | * the request_fn for the queue if it was in a stopped state when |
| 232 | * entered. Also see blk_stop_queue(). Queue lock must be held. |
| 233 | **/ |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 234 | void blk_start_queue(struct request_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 235 | { |
Paolo 'Blaisorblade' Giarrusso | a038e25 | 2006-06-05 12:09:01 +0200 | [diff] [blame] | 236 | WARN_ON(!irqs_disabled()); |
| 237 | |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 238 | queue_flag_clear(QUEUE_FLAG_STOPPED, q); |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 239 | __blk_run_queue(q); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 241 | EXPORT_SYMBOL(blk_start_queue); |
| 242 | |
| 243 | /** |
| 244 | * blk_stop_queue - stop a queue |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 245 | * @q: The &struct request_queue in question |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 246 | * |
| 247 | * Description: |
| 248 | * The Linux block layer assumes that a block driver will consume all |
| 249 | * entries on the request queue when the request_fn strategy is called. |
| 250 | * Often this will not happen, because of hardware limitations (queue |
| 251 | * depth settings). If a device driver gets a 'queue full' response, |
| 252 | * or if it simply chooses not to queue more I/O at one point, it can |
| 253 | * call this function to prevent the request_fn from being called until |
| 254 | * the driver has signalled it's ready to go again. This happens by calling |
| 255 | * blk_start_queue() to restart queue operations. Queue lock must be held. |
| 256 | **/ |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 257 | void blk_stop_queue(struct request_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 258 | { |
Tejun Heo | 136b572 | 2012-08-21 13:18:24 -0700 | [diff] [blame] | 259 | cancel_delayed_work(&q->delay_work); |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 260 | queue_flag_set(QUEUE_FLAG_STOPPED, q); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | } |
| 262 | EXPORT_SYMBOL(blk_stop_queue); |
| 263 | |
| 264 | /** |
| 265 | * blk_sync_queue - cancel any pending callbacks on a queue |
| 266 | * @q: the queue |
| 267 | * |
| 268 | * Description: |
| 269 | * The block layer may perform asynchronous callback activity |
| 270 | * on a queue, such as calling the unplug function after a timeout. |
| 271 | * A block device may call blk_sync_queue to ensure that any |
| 272 | * such activity is cancelled, thus allowing it to release resources |
Michael Opdenacker | 59c5159 | 2007-05-09 08:57:56 +0200 | [diff] [blame] | 273 | * that the callbacks might use. The caller must already have made sure |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 274 | * that its ->make_request_fn will not re-add plugging prior to calling |
| 275 | * this function. |
| 276 | * |
Vivek Goyal | da52777 | 2011-03-02 19:05:33 -0500 | [diff] [blame] | 277 | * This function does not cancel any asynchronous activity arising |
Masanari Iida | da3dae5 | 2014-09-09 01:27:23 +0900 | [diff] [blame] | 278 | * out of elevator or throttling code. That would require elevator_exit() |
Tejun Heo | 5efd611 | 2012-03-05 13:15:12 -0800 | [diff] [blame] | 279 | * and blkcg_exit_queue() to be called with queue lock initialized. |
Vivek Goyal | da52777 | 2011-03-02 19:05:33 -0500 | [diff] [blame] | 280 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 281 | */ |
| 282 | void blk_sync_queue(struct request_queue *q) |
| 283 | { |
Jens Axboe | 70ed28b | 2008-11-19 14:38:39 +0100 | [diff] [blame] | 284 | del_timer_sync(&q->timeout); |
Ming Lei | f04c1fe | 2013-12-26 21:31:36 +0800 | [diff] [blame] | 285 | |
| 286 | if (q->mq_ops) { |
| 287 | struct blk_mq_hw_ctx *hctx; |
| 288 | int i; |
| 289 | |
Christoph Hellwig | 70f4db6 | 2014-04-16 10:48:08 -0600 | [diff] [blame] | 290 | queue_for_each_hw_ctx(q, hctx, i) { |
| 291 | cancel_delayed_work_sync(&hctx->run_work); |
| 292 | cancel_delayed_work_sync(&hctx->delay_work); |
| 293 | } |
Ming Lei | f04c1fe | 2013-12-26 21:31:36 +0800 | [diff] [blame] | 294 | } else { |
| 295 | cancel_delayed_work_sync(&q->delay_work); |
| 296 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 297 | } |
| 298 | EXPORT_SYMBOL(blk_sync_queue); |
| 299 | |
| 300 | /** |
Bart Van Assche | c246e80 | 2012-12-06 14:32:01 +0100 | [diff] [blame] | 301 | * __blk_run_queue_uncond - run a queue whether or not it has been stopped |
| 302 | * @q: The queue to run |
| 303 | * |
| 304 | * Description: |
| 305 | * Invoke request handling on a queue if there are any pending requests. |
| 306 | * May be used to restart request handling after a request has completed. |
| 307 | * This variant runs the queue whether or not the queue has been |
| 308 | * stopped. Must be called with the queue lock held and interrupts |
| 309 | * disabled. See also @blk_run_queue. |
| 310 | */ |
| 311 | inline void __blk_run_queue_uncond(struct request_queue *q) |
| 312 | { |
| 313 | if (unlikely(blk_queue_dead(q))) |
| 314 | return; |
| 315 | |
Bart Van Assche | 24faf6f | 2012-11-28 13:46:45 +0100 | [diff] [blame] | 316 | /* |
| 317 | * Some request_fn implementations, e.g. scsi_request_fn(), unlock |
| 318 | * the queue lock internally. As a result multiple threads may be |
| 319 | * running such a request function concurrently. Keep track of the |
| 320 | * number of active request_fn invocations such that blk_drain_queue() |
| 321 | * can wait until all these request_fn calls have finished. |
| 322 | */ |
| 323 | q->request_fn_active++; |
Bart Van Assche | c246e80 | 2012-12-06 14:32:01 +0100 | [diff] [blame] | 324 | q->request_fn(q); |
Bart Van Assche | 24faf6f | 2012-11-28 13:46:45 +0100 | [diff] [blame] | 325 | q->request_fn_active--; |
Bart Van Assche | c246e80 | 2012-12-06 14:32:01 +0100 | [diff] [blame] | 326 | } |
Christoph Hellwig | a7928c1 | 2015-04-17 22:37:20 +0200 | [diff] [blame] | 327 | EXPORT_SYMBOL_GPL(__blk_run_queue_uncond); |
Bart Van Assche | c246e80 | 2012-12-06 14:32:01 +0100 | [diff] [blame] | 328 | |
| 329 | /** |
Jens Axboe | 80a4b58 | 2008-10-14 09:51:06 +0200 | [diff] [blame] | 330 | * __blk_run_queue - run a single device queue |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 331 | * @q: The queue to run |
Jens Axboe | 80a4b58 | 2008-10-14 09:51:06 +0200 | [diff] [blame] | 332 | * |
| 333 | * Description: |
| 334 | * See @blk_run_queue. This variant must be called with the queue lock |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 335 | * held and interrupts disabled. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | */ |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 337 | void __blk_run_queue(struct request_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 338 | { |
Tejun Heo | a538cd0 | 2009-04-23 11:05:17 +0900 | [diff] [blame] | 339 | if (unlikely(blk_queue_stopped(q))) |
| 340 | return; |
| 341 | |
Bart Van Assche | c246e80 | 2012-12-06 14:32:01 +0100 | [diff] [blame] | 342 | __blk_run_queue_uncond(q); |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 343 | } |
| 344 | EXPORT_SYMBOL(__blk_run_queue); |
Jens Axboe | dac07ec | 2006-05-11 08:20:16 +0200 | [diff] [blame] | 345 | |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 346 | /** |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 347 | * blk_run_queue_async - run a single device queue in workqueue context |
| 348 | * @q: The queue to run |
| 349 | * |
| 350 | * Description: |
| 351 | * Tells kblockd to perform the equivalent of @blk_run_queue on behalf |
Bart Van Assche | 7046057 | 2012-11-28 13:45:56 +0100 | [diff] [blame] | 352 | * of us. The caller must hold the queue lock. |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 353 | */ |
| 354 | void blk_run_queue_async(struct request_queue *q) |
| 355 | { |
Bart Van Assche | 7046057 | 2012-11-28 13:45:56 +0100 | [diff] [blame] | 356 | if (likely(!blk_queue_stopped(q) && !blk_queue_dead(q))) |
Tejun Heo | e7c2f96 | 2012-08-21 13:18:24 -0700 | [diff] [blame] | 357 | mod_delayed_work(kblockd_workqueue, &q->delay_work, 0); |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 358 | } |
Jens Axboe | c21e6be | 2011-04-19 13:32:46 +0200 | [diff] [blame] | 359 | EXPORT_SYMBOL(blk_run_queue_async); |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 360 | |
| 361 | /** |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 362 | * blk_run_queue - run a single device queue |
| 363 | * @q: The queue to run |
Jens Axboe | 80a4b58 | 2008-10-14 09:51:06 +0200 | [diff] [blame] | 364 | * |
| 365 | * Description: |
| 366 | * Invoke request handling on this queue, if it has pending work to do. |
Tejun Heo | a7f5579 | 2009-04-23 11:05:17 +0900 | [diff] [blame] | 367 | * May be used to restart queueing when a request has completed. |
Nick Piggin | 75ad23b | 2008-04-29 14:48:33 +0200 | [diff] [blame] | 368 | */ |
| 369 | void blk_run_queue(struct request_queue *q) |
| 370 | { |
| 371 | unsigned long flags; |
| 372 | |
| 373 | spin_lock_irqsave(q->queue_lock, flags); |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 374 | __blk_run_queue(q); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 375 | spin_unlock_irqrestore(q->queue_lock, flags); |
| 376 | } |
| 377 | EXPORT_SYMBOL(blk_run_queue); |
| 378 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 379 | void blk_put_queue(struct request_queue *q) |
Al Viro | 483f4af | 2006-03-18 18:34:37 -0500 | [diff] [blame] | 380 | { |
| 381 | kobject_put(&q->kobj); |
| 382 | } |
Jens Axboe | d86e0e8 | 2011-05-27 07:44:43 +0200 | [diff] [blame] | 383 | EXPORT_SYMBOL(blk_put_queue); |
Al Viro | 483f4af | 2006-03-18 18:34:37 -0500 | [diff] [blame] | 384 | |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 385 | /** |
Bart Van Assche | 807592a | 2012-11-28 13:43:38 +0100 | [diff] [blame] | 386 | * __blk_drain_queue - drain requests from request_queue |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 387 | * @q: queue to drain |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 388 | * @drain_all: whether to drain all requests or only the ones w/ ELVPRIV |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 389 | * |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 390 | * Drain requests from @q. If @drain_all is set, all requests are drained. |
| 391 | * If not, only ELVPRIV requests are drained. The caller is responsible |
| 392 | * for ensuring that no new requests which need to be drained are queued. |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 393 | */ |
Bart Van Assche | 807592a | 2012-11-28 13:43:38 +0100 | [diff] [blame] | 394 | static void __blk_drain_queue(struct request_queue *q, bool drain_all) |
| 395 | __releases(q->queue_lock) |
| 396 | __acquires(q->queue_lock) |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 397 | { |
Asias He | 458f27a | 2012-06-15 08:45:25 +0200 | [diff] [blame] | 398 | int i; |
| 399 | |
Bart Van Assche | 807592a | 2012-11-28 13:43:38 +0100 | [diff] [blame] | 400 | lockdep_assert_held(q->queue_lock); |
| 401 | |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 402 | while (true) { |
Tejun Heo | 481a7d6 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 403 | bool drain = false; |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 404 | |
Tejun Heo | b855b04 | 2012-03-06 21:24:55 +0100 | [diff] [blame] | 405 | /* |
| 406 | * The caller might be trying to drain @q before its |
| 407 | * elevator is initialized. |
| 408 | */ |
| 409 | if (q->elevator) |
| 410 | elv_drain_elevator(q); |
| 411 | |
Tejun Heo | 5efd611 | 2012-03-05 13:15:12 -0800 | [diff] [blame] | 412 | blkcg_drain_queue(q); |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 413 | |
Tejun Heo | 4eabc94 | 2011-12-15 20:03:04 +0100 | [diff] [blame] | 414 | /* |
| 415 | * This function might be called on a queue which failed |
Tejun Heo | b855b04 | 2012-03-06 21:24:55 +0100 | [diff] [blame] | 416 | * driver init after queue creation or is not yet fully |
| 417 | * active yet. Some drivers (e.g. fd and loop) get unhappy |
| 418 | * in such cases. Kick queue iff dispatch queue has |
| 419 | * something on it and @q has request_fn set. |
Tejun Heo | 4eabc94 | 2011-12-15 20:03:04 +0100 | [diff] [blame] | 420 | */ |
Tejun Heo | b855b04 | 2012-03-06 21:24:55 +0100 | [diff] [blame] | 421 | if (!list_empty(&q->queue_head) && q->request_fn) |
Tejun Heo | 4eabc94 | 2011-12-15 20:03:04 +0100 | [diff] [blame] | 422 | __blk_run_queue(q); |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 423 | |
Tejun Heo | 8a5ecdd | 2012-06-04 20:40:58 -0700 | [diff] [blame] | 424 | drain |= q->nr_rqs_elvpriv; |
Bart Van Assche | 24faf6f | 2012-11-28 13:46:45 +0100 | [diff] [blame] | 425 | drain |= q->request_fn_active; |
Tejun Heo | 481a7d6 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 426 | |
| 427 | /* |
| 428 | * Unfortunately, requests are queued at and tracked from |
| 429 | * multiple places and there's no single counter which can |
| 430 | * be drained. Check all the queues and counters. |
| 431 | */ |
| 432 | if (drain_all) { |
Ming Lei | e97c293 | 2014-09-25 23:23:46 +0800 | [diff] [blame] | 433 | struct blk_flush_queue *fq = blk_get_flush_queue(q, NULL); |
Tejun Heo | 481a7d6 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 434 | drain |= !list_empty(&q->queue_head); |
| 435 | for (i = 0; i < 2; i++) { |
Tejun Heo | 8a5ecdd | 2012-06-04 20:40:58 -0700 | [diff] [blame] | 436 | drain |= q->nr_rqs[i]; |
Tejun Heo | 481a7d6 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 437 | drain |= q->in_flight[i]; |
Ming Lei | 7c94e1c | 2014-09-25 23:23:43 +0800 | [diff] [blame] | 438 | if (fq) |
| 439 | drain |= !list_empty(&fq->flush_queue[i]); |
Tejun Heo | 481a7d6 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 440 | } |
| 441 | } |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 442 | |
Tejun Heo | 481a7d6 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 443 | if (!drain) |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 444 | break; |
Bart Van Assche | 807592a | 2012-11-28 13:43:38 +0100 | [diff] [blame] | 445 | |
| 446 | spin_unlock_irq(q->queue_lock); |
| 447 | |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 448 | msleep(10); |
Bart Van Assche | 807592a | 2012-11-28 13:43:38 +0100 | [diff] [blame] | 449 | |
| 450 | spin_lock_irq(q->queue_lock); |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 451 | } |
Asias He | 458f27a | 2012-06-15 08:45:25 +0200 | [diff] [blame] | 452 | |
| 453 | /* |
| 454 | * With queue marked dead, any woken up waiter will fail the |
| 455 | * allocation path, so the wakeup chaining is lost and we're |
| 456 | * left with hung waiters. We need to wake up those waiters. |
| 457 | */ |
| 458 | if (q->request_fn) { |
Tejun Heo | a051661 | 2012-06-26 15:05:44 -0700 | [diff] [blame] | 459 | struct request_list *rl; |
| 460 | |
Tejun Heo | a051661 | 2012-06-26 15:05:44 -0700 | [diff] [blame] | 461 | blk_queue_for_each_rl(rl, q) |
| 462 | for (i = 0; i < ARRAY_SIZE(rl->wait); i++) |
| 463 | wake_up_all(&rl->wait[i]); |
Asias He | 458f27a | 2012-06-15 08:45:25 +0200 | [diff] [blame] | 464 | } |
Tejun Heo | e3c78ca | 2011-10-19 14:32:38 +0200 | [diff] [blame] | 465 | } |
| 466 | |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 467 | /** |
Tejun Heo | d732580 | 2012-03-05 13:14:58 -0800 | [diff] [blame] | 468 | * blk_queue_bypass_start - enter queue bypass mode |
| 469 | * @q: queue of interest |
| 470 | * |
| 471 | * In bypass mode, only the dispatch FIFO queue of @q is used. This |
| 472 | * function makes @q enter bypass mode and drains all requests which were |
Tejun Heo | 6ecf23a | 2012-03-05 13:14:59 -0800 | [diff] [blame] | 473 | * throttled or issued before. On return, it's guaranteed that no request |
Tejun Heo | 80fd997 | 2012-04-13 14:50:53 -0700 | [diff] [blame] | 474 | * is being throttled or has ELVPRIV set and blk_queue_bypass() %true |
| 475 | * inside queue or RCU read lock. |
Tejun Heo | d732580 | 2012-03-05 13:14:58 -0800 | [diff] [blame] | 476 | */ |
| 477 | void blk_queue_bypass_start(struct request_queue *q) |
| 478 | { |
| 479 | spin_lock_irq(q->queue_lock); |
Tejun Heo | 776687b | 2014-07-01 10:29:17 -0600 | [diff] [blame] | 480 | q->bypass_depth++; |
Tejun Heo | d732580 | 2012-03-05 13:14:58 -0800 | [diff] [blame] | 481 | queue_flag_set(QUEUE_FLAG_BYPASS, q); |
| 482 | spin_unlock_irq(q->queue_lock); |
| 483 | |
Tejun Heo | 776687b | 2014-07-01 10:29:17 -0600 | [diff] [blame] | 484 | /* |
| 485 | * Queues start drained. Skip actual draining till init is |
| 486 | * complete. This avoids lenghty delays during queue init which |
| 487 | * can happen many times during boot. |
| 488 | */ |
| 489 | if (blk_queue_init_done(q)) { |
Bart Van Assche | 807592a | 2012-11-28 13:43:38 +0100 | [diff] [blame] | 490 | spin_lock_irq(q->queue_lock); |
| 491 | __blk_drain_queue(q, false); |
| 492 | spin_unlock_irq(q->queue_lock); |
| 493 | |
Tejun Heo | b82d4b1 | 2012-04-13 13:11:31 -0700 | [diff] [blame] | 494 | /* ensure blk_queue_bypass() is %true inside RCU read lock */ |
| 495 | synchronize_rcu(); |
| 496 | } |
Tejun Heo | d732580 | 2012-03-05 13:14:58 -0800 | [diff] [blame] | 497 | } |
| 498 | EXPORT_SYMBOL_GPL(blk_queue_bypass_start); |
| 499 | |
| 500 | /** |
| 501 | * blk_queue_bypass_end - leave queue bypass mode |
| 502 | * @q: queue of interest |
| 503 | * |
| 504 | * Leave bypass mode and restore the normal queueing behavior. |
| 505 | */ |
| 506 | void blk_queue_bypass_end(struct request_queue *q) |
| 507 | { |
| 508 | spin_lock_irq(q->queue_lock); |
| 509 | if (!--q->bypass_depth) |
| 510 | queue_flag_clear(QUEUE_FLAG_BYPASS, q); |
| 511 | WARN_ON_ONCE(q->bypass_depth < 0); |
| 512 | spin_unlock_irq(q->queue_lock); |
| 513 | } |
| 514 | EXPORT_SYMBOL_GPL(blk_queue_bypass_end); |
| 515 | |
Jens Axboe | aed3ea9 | 2014-12-22 14:04:42 -0700 | [diff] [blame] | 516 | void blk_set_queue_dying(struct request_queue *q) |
| 517 | { |
| 518 | queue_flag_set_unlocked(QUEUE_FLAG_DYING, q); |
| 519 | |
| 520 | if (q->mq_ops) |
| 521 | blk_mq_wake_waiters(q); |
| 522 | else { |
| 523 | struct request_list *rl; |
| 524 | |
| 525 | blk_queue_for_each_rl(rl, q) { |
| 526 | if (rl->rq_pool) { |
| 527 | wake_up(&rl->wait[BLK_RW_SYNC]); |
| 528 | wake_up(&rl->wait[BLK_RW_ASYNC]); |
| 529 | } |
| 530 | } |
| 531 | } |
| 532 | } |
| 533 | EXPORT_SYMBOL_GPL(blk_set_queue_dying); |
| 534 | |
Tejun Heo | d732580 | 2012-03-05 13:14:58 -0800 | [diff] [blame] | 535 | /** |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 536 | * blk_cleanup_queue - shutdown a request queue |
| 537 | * @q: request queue to shutdown |
| 538 | * |
Bart Van Assche | c246e80 | 2012-12-06 14:32:01 +0100 | [diff] [blame] | 539 | * Mark @q DYING, drain all pending requests, mark @q DEAD, destroy and |
| 540 | * put it. All future requests will be failed immediately with -ENODEV. |
Vivek Goyal | c94a96a | 2011-03-02 19:04:42 -0500 | [diff] [blame] | 541 | */ |
Jens Axboe | 6728cb0 | 2008-01-31 13:03:55 +0100 | [diff] [blame] | 542 | void blk_cleanup_queue(struct request_queue *q) |
Al Viro | 483f4af | 2006-03-18 18:34:37 -0500 | [diff] [blame] | 543 | { |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 544 | spinlock_t *lock = q->queue_lock; |
Jens Axboe | e3335de | 2008-09-18 09:22:54 -0700 | [diff] [blame] | 545 | |
Bart Van Assche | 3f3299d | 2012-11-28 13:42:38 +0100 | [diff] [blame] | 546 | /* mark @q DYING, no new request or merges will be allowed afterwards */ |
Al Viro | 483f4af | 2006-03-18 18:34:37 -0500 | [diff] [blame] | 547 | mutex_lock(&q->sysfs_lock); |
Jens Axboe | aed3ea9 | 2014-12-22 14:04:42 -0700 | [diff] [blame] | 548 | blk_set_queue_dying(q); |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 549 | spin_lock_irq(lock); |
Tejun Heo | 6ecf23a | 2012-03-05 13:14:59 -0800 | [diff] [blame] | 550 | |
Tejun Heo | 80fd997 | 2012-04-13 14:50:53 -0700 | [diff] [blame] | 551 | /* |
Bart Van Assche | 3f3299d | 2012-11-28 13:42:38 +0100 | [diff] [blame] | 552 | * A dying queue is permanently in bypass mode till released. Note |
Tejun Heo | 80fd997 | 2012-04-13 14:50:53 -0700 | [diff] [blame] | 553 | * that, unlike blk_queue_bypass_start(), we aren't performing |
| 554 | * synchronize_rcu() after entering bypass mode to avoid the delay |
| 555 | * as some drivers create and destroy a lot of queues while |
| 556 | * probing. This is still safe because blk_release_queue() will be |
| 557 | * called only after the queue refcnt drops to zero and nothing, |
| 558 | * RCU or not, would be traversing the queue by then. |
| 559 | */ |
Tejun Heo | 6ecf23a | 2012-03-05 13:14:59 -0800 | [diff] [blame] | 560 | q->bypass_depth++; |
| 561 | queue_flag_set(QUEUE_FLAG_BYPASS, q); |
| 562 | |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 563 | queue_flag_set(QUEUE_FLAG_NOMERGES, q); |
| 564 | queue_flag_set(QUEUE_FLAG_NOXMERGES, q); |
Bart Van Assche | 3f3299d | 2012-11-28 13:42:38 +0100 | [diff] [blame] | 565 | queue_flag_set(QUEUE_FLAG_DYING, q); |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 566 | spin_unlock_irq(lock); |
| 567 | mutex_unlock(&q->sysfs_lock); |
| 568 | |
Bart Van Assche | c246e80 | 2012-12-06 14:32:01 +0100 | [diff] [blame] | 569 | /* |
| 570 | * Drain all requests queued before DYING marking. Set DEAD flag to |
| 571 | * prevent that q->request_fn() gets invoked after draining finished. |
| 572 | */ |
Dan Williams | 3ef28e8 | 2015-10-21 13:20:12 -0400 | [diff] [blame] | 573 | blk_freeze_queue(q); |
| 574 | spin_lock_irq(lock); |
| 575 | if (!q->mq_ops) |
Ming Lei | 43a5e4e | 2013-12-26 21:31:35 +0800 | [diff] [blame] | 576 | __blk_drain_queue(q, true); |
Bart Van Assche | c246e80 | 2012-12-06 14:32:01 +0100 | [diff] [blame] | 577 | queue_flag_set(QUEUE_FLAG_DEAD, q); |
Bart Van Assche | 807592a | 2012-11-28 13:43:38 +0100 | [diff] [blame] | 578 | spin_unlock_irq(lock); |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 579 | |
Dan Williams | 5a48fc1 | 2015-10-21 13:20:23 -0400 | [diff] [blame] | 580 | /* for synchronous bio-based driver finish in-flight integrity i/o */ |
| 581 | blk_flush_integrity(); |
| 582 | |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 583 | /* @q won't process any more request, flush async actions */ |
| 584 | del_timer_sync(&q->backing_dev_info.laptop_mode_wb_timer); |
| 585 | blk_sync_queue(q); |
| 586 | |
Bart Van Assche | 45a9c9d | 2014-12-09 16:57:48 +0100 | [diff] [blame] | 587 | if (q->mq_ops) |
| 588 | blk_mq_free_queue(q); |
Dan Williams | 3ef28e8 | 2015-10-21 13:20:12 -0400 | [diff] [blame] | 589 | percpu_ref_exit(&q->q_usage_counter); |
Bart Van Assche | 45a9c9d | 2014-12-09 16:57:48 +0100 | [diff] [blame] | 590 | |
Asias He | 5e5cfac | 2012-05-24 23:28:52 +0800 | [diff] [blame] | 591 | spin_lock_irq(lock); |
| 592 | if (q->queue_lock != &q->__queue_lock) |
| 593 | q->queue_lock = &q->__queue_lock; |
| 594 | spin_unlock_irq(lock); |
| 595 | |
Tejun Heo | b02176f | 2015-09-08 12:20:22 -0400 | [diff] [blame] | 596 | bdi_unregister(&q->backing_dev_info); |
NeilBrown | 6cd18e7 | 2015-04-27 14:12:22 +1000 | [diff] [blame] | 597 | |
Tejun Heo | c9a929d | 2011-10-19 14:42:16 +0200 | [diff] [blame] | 598 | /* @q is and will stay empty, shutdown and put */ |
Al Viro | 483f4af | 2006-03-18 18:34:37 -0500 | [diff] [blame] | 599 | blk_put_queue(q); |
| 600 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 601 | EXPORT_SYMBOL(blk_cleanup_queue); |
| 602 | |
David Rientjes | 271508d | 2015-03-24 16:21:16 -0700 | [diff] [blame] | 603 | /* Allocate memory local to the request queue */ |
| 604 | static void *alloc_request_struct(gfp_t gfp_mask, void *data) |
| 605 | { |
| 606 | int nid = (int)(long)data; |
| 607 | return kmem_cache_alloc_node(request_cachep, gfp_mask, nid); |
| 608 | } |
| 609 | |
| 610 | static void free_request_struct(void *element, void *unused) |
| 611 | { |
| 612 | kmem_cache_free(request_cachep, element); |
| 613 | } |
| 614 | |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 615 | int blk_init_rl(struct request_list *rl, struct request_queue *q, |
| 616 | gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 617 | { |
Mike Snitzer | 1abec4f | 2010-05-25 13:15:15 -0400 | [diff] [blame] | 618 | if (unlikely(rl->rq_pool)) |
| 619 | return 0; |
| 620 | |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 621 | rl->q = q; |
Jens Axboe | 1faa16d | 2009-04-06 14:48:01 +0200 | [diff] [blame] | 622 | rl->count[BLK_RW_SYNC] = rl->count[BLK_RW_ASYNC] = 0; |
| 623 | rl->starved[BLK_RW_SYNC] = rl->starved[BLK_RW_ASYNC] = 0; |
Jens Axboe | 1faa16d | 2009-04-06 14:48:01 +0200 | [diff] [blame] | 624 | init_waitqueue_head(&rl->wait[BLK_RW_SYNC]); |
| 625 | init_waitqueue_head(&rl->wait[BLK_RW_ASYNC]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 626 | |
David Rientjes | 271508d | 2015-03-24 16:21:16 -0700 | [diff] [blame] | 627 | rl->rq_pool = mempool_create_node(BLKDEV_MIN_RQ, alloc_request_struct, |
| 628 | free_request_struct, |
| 629 | (void *)(long)q->node, gfp_mask, |
| 630 | q->node); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | if (!rl->rq_pool) |
| 632 | return -ENOMEM; |
| 633 | |
| 634 | return 0; |
| 635 | } |
| 636 | |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 637 | void blk_exit_rl(struct request_list *rl) |
| 638 | { |
| 639 | if (rl->rq_pool) |
| 640 | mempool_destroy(rl->rq_pool); |
| 641 | } |
| 642 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 643 | struct request_queue *blk_alloc_queue(gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 644 | { |
Ezequiel Garcia | c304a51 | 2012-11-10 10:39:44 +0100 | [diff] [blame] | 645 | return blk_alloc_queue_node(gfp_mask, NUMA_NO_NODE); |
Christoph Lameter | 1946089 | 2005-06-23 00:08:19 -0700 | [diff] [blame] | 646 | } |
| 647 | EXPORT_SYMBOL(blk_alloc_queue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 648 | |
Christoph Hellwig | 6f3b0e8 | 2015-11-26 09:13:05 +0100 | [diff] [blame] | 649 | int blk_queue_enter(struct request_queue *q, bool nowait) |
Dan Williams | 3ef28e8 | 2015-10-21 13:20:12 -0400 | [diff] [blame] | 650 | { |
| 651 | while (true) { |
| 652 | int ret; |
| 653 | |
| 654 | if (percpu_ref_tryget_live(&q->q_usage_counter)) |
| 655 | return 0; |
| 656 | |
Christoph Hellwig | 6f3b0e8 | 2015-11-26 09:13:05 +0100 | [diff] [blame] | 657 | if (nowait) |
Dan Williams | 3ef28e8 | 2015-10-21 13:20:12 -0400 | [diff] [blame] | 658 | return -EBUSY; |
| 659 | |
| 660 | ret = wait_event_interruptible(q->mq_freeze_wq, |
| 661 | !atomic_read(&q->mq_freeze_depth) || |
| 662 | blk_queue_dying(q)); |
| 663 | if (blk_queue_dying(q)) |
| 664 | return -ENODEV; |
| 665 | if (ret) |
| 666 | return ret; |
| 667 | } |
| 668 | } |
| 669 | |
| 670 | void blk_queue_exit(struct request_queue *q) |
| 671 | { |
| 672 | percpu_ref_put(&q->q_usage_counter); |
| 673 | } |
| 674 | |
| 675 | static void blk_queue_usage_counter_release(struct percpu_ref *ref) |
| 676 | { |
| 677 | struct request_queue *q = |
| 678 | container_of(ref, struct request_queue, q_usage_counter); |
| 679 | |
| 680 | wake_up_all(&q->mq_freeze_wq); |
| 681 | } |
| 682 | |
Christoph Hellwig | 287922eb | 2015-10-30 20:57:30 +0800 | [diff] [blame] | 683 | static void blk_rq_timed_out_timer(unsigned long data) |
| 684 | { |
| 685 | struct request_queue *q = (struct request_queue *)data; |
| 686 | |
| 687 | kblockd_schedule_work(&q->timeout_work); |
| 688 | } |
| 689 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 690 | struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id) |
Christoph Lameter | 1946089 | 2005-06-23 00:08:19 -0700 | [diff] [blame] | 691 | { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 692 | struct request_queue *q; |
Peter Zijlstra | e0bf68d | 2007-10-16 23:25:46 -0700 | [diff] [blame] | 693 | int err; |
Christoph Lameter | 1946089 | 2005-06-23 00:08:19 -0700 | [diff] [blame] | 694 | |
Jens Axboe | 8324aa9 | 2008-01-29 14:51:59 +0100 | [diff] [blame] | 695 | q = kmem_cache_alloc_node(blk_requestq_cachep, |
Christoph Lameter | 94f6030 | 2007-07-17 04:03:29 -0700 | [diff] [blame] | 696 | gfp_mask | __GFP_ZERO, node_id); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 697 | if (!q) |
| 698 | return NULL; |
| 699 | |
Dan Carpenter | 00380a4 | 2012-03-23 09:58:54 +0100 | [diff] [blame] | 700 | q->id = ida_simple_get(&blk_queue_ida, 0, 0, gfp_mask); |
Tejun Heo | a73f730 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 701 | if (q->id < 0) |
Ming Lei | 3d2936f | 2014-05-27 23:35:14 +0800 | [diff] [blame] | 702 | goto fail_q; |
Tejun Heo | a73f730 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 703 | |
Kent Overstreet | 54efd50 | 2015-04-23 22:37:18 -0700 | [diff] [blame] | 704 | q->bio_split = bioset_create(BIO_POOL_SIZE, 0); |
| 705 | if (!q->bio_split) |
| 706 | goto fail_id; |
| 707 | |
Jens Axboe | 0989a02 | 2009-06-12 14:42:56 +0200 | [diff] [blame] | 708 | q->backing_dev_info.ra_pages = |
| 709 | (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE; |
Tejun Heo | 89e9b9e | 2015-05-22 17:13:36 -0400 | [diff] [blame] | 710 | q->backing_dev_info.capabilities = BDI_CAP_CGROUP_WRITEBACK; |
Jens Axboe | d993831 | 2009-06-12 14:45:52 +0200 | [diff] [blame] | 711 | q->backing_dev_info.name = "block"; |
Mike Snitzer | 5151412 | 2011-11-23 10:59:13 +0100 | [diff] [blame] | 712 | q->node = node_id; |
Jens Axboe | 0989a02 | 2009-06-12 14:42:56 +0200 | [diff] [blame] | 713 | |
Peter Zijlstra | e0bf68d | 2007-10-16 23:25:46 -0700 | [diff] [blame] | 714 | err = bdi_init(&q->backing_dev_info); |
Tejun Heo | a73f730 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 715 | if (err) |
Kent Overstreet | 54efd50 | 2015-04-23 22:37:18 -0700 | [diff] [blame] | 716 | goto fail_split; |
Peter Zijlstra | e0bf68d | 2007-10-16 23:25:46 -0700 | [diff] [blame] | 717 | |
Matthew Garrett | 31373d0 | 2010-04-06 14:25:14 +0200 | [diff] [blame] | 718 | setup_timer(&q->backing_dev_info.laptop_mode_wb_timer, |
| 719 | laptop_mode_timer_fn, (unsigned long) q); |
Jens Axboe | 242f9dc | 2008-09-14 05:55:09 -0700 | [diff] [blame] | 720 | setup_timer(&q->timeout, blk_rq_timed_out_timer, (unsigned long) q); |
Tejun Heo | b855b04 | 2012-03-06 21:24:55 +0100 | [diff] [blame] | 721 | INIT_LIST_HEAD(&q->queue_head); |
Jens Axboe | 242f9dc | 2008-09-14 05:55:09 -0700 | [diff] [blame] | 722 | INIT_LIST_HEAD(&q->timeout_list); |
Tejun Heo | a612fdd | 2011-12-14 00:33:41 +0100 | [diff] [blame] | 723 | INIT_LIST_HEAD(&q->icq_list); |
Tejun Heo | 4eef304 | 2012-03-05 13:15:18 -0800 | [diff] [blame] | 724 | #ifdef CONFIG_BLK_CGROUP |
Tejun Heo | e8989fa | 2012-03-05 13:15:20 -0800 | [diff] [blame] | 725 | INIT_LIST_HEAD(&q->blkg_list); |
Tejun Heo | 4eef304 | 2012-03-05 13:15:18 -0800 | [diff] [blame] | 726 | #endif |
Jens Axboe | 3cca6dc | 2011-03-02 11:08:00 -0500 | [diff] [blame] | 727 | INIT_DELAYED_WORK(&q->delay_work, blk_delay_work); |
Al Viro | 483f4af | 2006-03-18 18:34:37 -0500 | [diff] [blame] | 728 | |
Jens Axboe | 8324aa9 | 2008-01-29 14:51:59 +0100 | [diff] [blame] | 729 | kobject_init(&q->kobj, &blk_queue_ktype); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 730 | |
Al Viro | 483f4af | 2006-03-18 18:34:37 -0500 | [diff] [blame] | 731 | mutex_init(&q->sysfs_lock); |
Neil Brown | e7e72bf | 2008-05-14 16:05:54 -0700 | [diff] [blame] | 732 | spin_lock_init(&q->__queue_lock); |
Al Viro | 483f4af | 2006-03-18 18:34:37 -0500 | [diff] [blame] | 733 | |
Vivek Goyal | c94a96a | 2011-03-02 19:04:42 -0500 | [diff] [blame] | 734 | /* |
| 735 | * By default initialize queue_lock to internal lock and driver can |
| 736 | * override it later if need be. |
| 737 | */ |
| 738 | q->queue_lock = &q->__queue_lock; |
| 739 | |
Tejun Heo | b82d4b1 | 2012-04-13 13:11:31 -0700 | [diff] [blame] | 740 | /* |
| 741 | * A queue starts its life with bypass turned on to avoid |
| 742 | * unnecessary bypass on/off overhead and nasty surprises during |
Tejun Heo | 749fefe | 2012-09-20 14:08:52 -0700 | [diff] [blame] | 743 | * init. The initial bypass will be finished when the queue is |
| 744 | * registered by blk_register_queue(). |
Tejun Heo | b82d4b1 | 2012-04-13 13:11:31 -0700 | [diff] [blame] | 745 | */ |
| 746 | q->bypass_depth = 1; |
| 747 | __set_bit(QUEUE_FLAG_BYPASS, &q->queue_flags); |
| 748 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 749 | init_waitqueue_head(&q->mq_freeze_wq); |
| 750 | |
Dan Williams | 3ef28e8 | 2015-10-21 13:20:12 -0400 | [diff] [blame] | 751 | /* |
| 752 | * Init percpu_ref in atomic mode so that it's faster to shutdown. |
| 753 | * See blk_register_queue() for details. |
| 754 | */ |
| 755 | if (percpu_ref_init(&q->q_usage_counter, |
| 756 | blk_queue_usage_counter_release, |
| 757 | PERCPU_REF_INIT_ATOMIC, GFP_KERNEL)) |
Mikulas Patocka | fff4996 | 2013-10-14 12:11:36 -0400 | [diff] [blame] | 758 | goto fail_bdi; |
Tejun Heo | f51b802 | 2012-03-05 13:15:05 -0800 | [diff] [blame] | 759 | |
Dan Williams | 3ef28e8 | 2015-10-21 13:20:12 -0400 | [diff] [blame] | 760 | if (blkcg_init_queue(q)) |
| 761 | goto fail_ref; |
| 762 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 763 | return q; |
Tejun Heo | a73f730 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 764 | |
Dan Williams | 3ef28e8 | 2015-10-21 13:20:12 -0400 | [diff] [blame] | 765 | fail_ref: |
| 766 | percpu_ref_exit(&q->q_usage_counter); |
Mikulas Patocka | fff4996 | 2013-10-14 12:11:36 -0400 | [diff] [blame] | 767 | fail_bdi: |
| 768 | bdi_destroy(&q->backing_dev_info); |
Kent Overstreet | 54efd50 | 2015-04-23 22:37:18 -0700 | [diff] [blame] | 769 | fail_split: |
| 770 | bioset_free(q->bio_split); |
Tejun Heo | a73f730 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 771 | fail_id: |
| 772 | ida_simple_remove(&blk_queue_ida, q->id); |
| 773 | fail_q: |
| 774 | kmem_cache_free(blk_requestq_cachep, q); |
| 775 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 776 | } |
Christoph Lameter | 1946089 | 2005-06-23 00:08:19 -0700 | [diff] [blame] | 777 | EXPORT_SYMBOL(blk_alloc_queue_node); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 778 | |
| 779 | /** |
| 780 | * blk_init_queue - prepare a request queue for use with a block device |
| 781 | * @rfn: The function to be called to process requests that have been |
| 782 | * placed on the queue. |
| 783 | * @lock: Request queue spin lock |
| 784 | * |
| 785 | * Description: |
| 786 | * If a block device wishes to use the standard request handling procedures, |
| 787 | * which sorts requests and coalesces adjacent requests, then it must |
| 788 | * call blk_init_queue(). The function @rfn will be called when there |
| 789 | * are requests on the queue that need to be processed. If the device |
| 790 | * supports plugging, then @rfn may not be called immediately when requests |
| 791 | * are available on the queue, but may be called at some time later instead. |
| 792 | * Plugged queues are generally unplugged when a buffer belonging to one |
| 793 | * of the requests on the queue is needed, or due to memory pressure. |
| 794 | * |
| 795 | * @rfn is not required, or even expected, to remove all requests off the |
| 796 | * queue, but only as many as it can handle at a time. If it does leave |
| 797 | * requests on the queue, it is responsible for arranging that the requests |
| 798 | * get dealt with eventually. |
| 799 | * |
| 800 | * The queue spin lock must be held while manipulating the requests on the |
Paolo 'Blaisorblade' Giarrusso | a038e25 | 2006-06-05 12:09:01 +0200 | [diff] [blame] | 801 | * request queue; this lock will be taken also from interrupt context, so irq |
| 802 | * disabling is needed for it. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 803 | * |
Randy Dunlap | 710027a | 2008-08-19 20:13:11 +0200 | [diff] [blame] | 804 | * Function returns a pointer to the initialized request queue, or %NULL if |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 805 | * it didn't succeed. |
| 806 | * |
| 807 | * Note: |
| 808 | * blk_init_queue() must be paired with a blk_cleanup_queue() call |
| 809 | * when the block device is deactivated (such as at module unload). |
| 810 | **/ |
Christoph Lameter | 1946089 | 2005-06-23 00:08:19 -0700 | [diff] [blame] | 811 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 812 | struct request_queue *blk_init_queue(request_fn_proc *rfn, spinlock_t *lock) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 813 | { |
Ezequiel Garcia | c304a51 | 2012-11-10 10:39:44 +0100 | [diff] [blame] | 814 | return blk_init_queue_node(rfn, lock, NUMA_NO_NODE); |
Christoph Lameter | 1946089 | 2005-06-23 00:08:19 -0700 | [diff] [blame] | 815 | } |
| 816 | EXPORT_SYMBOL(blk_init_queue); |
| 817 | |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 818 | struct request_queue * |
Christoph Lameter | 1946089 | 2005-06-23 00:08:19 -0700 | [diff] [blame] | 819 | blk_init_queue_node(request_fn_proc *rfn, spinlock_t *lock, int node_id) |
| 820 | { |
Mike Snitzer | c86d1b8 | 2010-06-03 11:34:52 -0600 | [diff] [blame] | 821 | struct request_queue *uninit_q, *q; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 822 | |
Mike Snitzer | c86d1b8 | 2010-06-03 11:34:52 -0600 | [diff] [blame] | 823 | uninit_q = blk_alloc_queue_node(GFP_KERNEL, node_id); |
| 824 | if (!uninit_q) |
| 825 | return NULL; |
| 826 | |
Mike Snitzer | 5151412 | 2011-11-23 10:59:13 +0100 | [diff] [blame] | 827 | q = blk_init_allocated_queue(uninit_q, rfn, lock); |
Mike Snitzer | c86d1b8 | 2010-06-03 11:34:52 -0600 | [diff] [blame] | 828 | if (!q) |
Mike Snitzer | 7982e90 | 2014-03-08 17:20:01 -0700 | [diff] [blame] | 829 | blk_cleanup_queue(uninit_q); |
Christoph Hellwig | 1874198 | 2014-02-10 09:29:00 -0700 | [diff] [blame] | 830 | |
Mike Snitzer | 7982e90 | 2014-03-08 17:20:01 -0700 | [diff] [blame] | 831 | return q; |
Mike Snitzer | 01effb0 | 2010-05-11 08:57:42 +0200 | [diff] [blame] | 832 | } |
| 833 | EXPORT_SYMBOL(blk_init_queue_node); |
| 834 | |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 835 | static blk_qc_t blk_queue_bio(struct request_queue *q, struct bio *bio); |
Mike Snitzer | 336b7e1 | 2015-05-11 14:06:32 -0400 | [diff] [blame] | 836 | |
Mike Snitzer | 01effb0 | 2010-05-11 08:57:42 +0200 | [diff] [blame] | 837 | struct request_queue * |
| 838 | blk_init_allocated_queue(struct request_queue *q, request_fn_proc *rfn, |
| 839 | spinlock_t *lock) |
| 840 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 841 | if (!q) |
| 842 | return NULL; |
| 843 | |
Ming Lei | f70ced0 | 2014-09-25 23:23:47 +0800 | [diff] [blame] | 844 | q->fq = blk_alloc_flush_queue(q, NUMA_NO_NODE, 0); |
Ming Lei | ba48338 | 2014-09-25 23:23:44 +0800 | [diff] [blame] | 845 | if (!q->fq) |
Mike Snitzer | 7982e90 | 2014-03-08 17:20:01 -0700 | [diff] [blame] | 846 | return NULL; |
| 847 | |
Tejun Heo | a051661 | 2012-06-26 15:05:44 -0700 | [diff] [blame] | 848 | if (blk_init_rl(&q->root_rl, q, GFP_KERNEL)) |
Dave Jones | 708f04d | 2014-03-20 15:03:58 -0600 | [diff] [blame] | 849 | goto fail; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 850 | |
Christoph Hellwig | 287922eb | 2015-10-30 20:57:30 +0800 | [diff] [blame] | 851 | INIT_WORK(&q->timeout_work, blk_timeout_work); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 852 | q->request_fn = rfn; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 853 | q->prep_rq_fn = NULL; |
James Bottomley | 28018c2 | 2010-07-01 19:49:17 +0900 | [diff] [blame] | 854 | q->unprep_rq_fn = NULL; |
Tejun Heo | 60ea822 | 2012-09-20 14:09:30 -0700 | [diff] [blame] | 855 | q->queue_flags |= QUEUE_FLAG_DEFAULT; |
Vivek Goyal | c94a96a | 2011-03-02 19:04:42 -0500 | [diff] [blame] | 856 | |
| 857 | /* Override internal queue lock with supplied lock pointer */ |
| 858 | if (lock) |
| 859 | q->queue_lock = lock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 860 | |
Jens Axboe | f3b144a | 2009-03-06 08:48:33 +0100 | [diff] [blame] | 861 | /* |
| 862 | * This also sets hw/phys segments, boundary and size |
| 863 | */ |
Jens Axboe | c20e8de | 2011-09-12 12:03:37 +0200 | [diff] [blame] | 864 | blk_queue_make_request(q, blk_queue_bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 865 | |
Alan Stern | 44ec954 | 2007-02-20 11:01:57 -0500 | [diff] [blame] | 866 | q->sg_reserved_size = INT_MAX; |
| 867 | |
Tomoki Sekiyama | eb1c160 | 2013-10-15 16:42:16 -0600 | [diff] [blame] | 868 | /* Protect q->elevator from elevator_change */ |
| 869 | mutex_lock(&q->sysfs_lock); |
| 870 | |
Tejun Heo | b82d4b1 | 2012-04-13 13:11:31 -0700 | [diff] [blame] | 871 | /* init elevator */ |
Tomoki Sekiyama | eb1c160 | 2013-10-15 16:42:16 -0600 | [diff] [blame] | 872 | if (elevator_init(q, NULL)) { |
| 873 | mutex_unlock(&q->sysfs_lock); |
Dave Jones | 708f04d | 2014-03-20 15:03:58 -0600 | [diff] [blame] | 874 | goto fail; |
Tomoki Sekiyama | eb1c160 | 2013-10-15 16:42:16 -0600 | [diff] [blame] | 875 | } |
| 876 | |
| 877 | mutex_unlock(&q->sysfs_lock); |
| 878 | |
Tejun Heo | b82d4b1 | 2012-04-13 13:11:31 -0700 | [diff] [blame] | 879 | return q; |
Dave Jones | 708f04d | 2014-03-20 15:03:58 -0600 | [diff] [blame] | 880 | |
| 881 | fail: |
Ming Lei | ba48338 | 2014-09-25 23:23:44 +0800 | [diff] [blame] | 882 | blk_free_flush_queue(q->fq); |
Dave Jones | 708f04d | 2014-03-20 15:03:58 -0600 | [diff] [blame] | 883 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 884 | } |
Mike Snitzer | 5151412 | 2011-11-23 10:59:13 +0100 | [diff] [blame] | 885 | EXPORT_SYMBOL(blk_init_allocated_queue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 886 | |
Tejun Heo | 09ac46c | 2011-12-14 00:33:38 +0100 | [diff] [blame] | 887 | bool blk_get_queue(struct request_queue *q) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 888 | { |
Bart Van Assche | 3f3299d | 2012-11-28 13:42:38 +0100 | [diff] [blame] | 889 | if (likely(!blk_queue_dying(q))) { |
Tejun Heo | 09ac46c | 2011-12-14 00:33:38 +0100 | [diff] [blame] | 890 | __blk_get_queue(q); |
| 891 | return true; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 892 | } |
| 893 | |
Tejun Heo | 09ac46c | 2011-12-14 00:33:38 +0100 | [diff] [blame] | 894 | return false; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 895 | } |
Jens Axboe | d86e0e8 | 2011-05-27 07:44:43 +0200 | [diff] [blame] | 896 | EXPORT_SYMBOL(blk_get_queue); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 897 | |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 898 | static inline void blk_free_request(struct request_list *rl, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 899 | { |
Tejun Heo | f1f8cc9 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 900 | if (rq->cmd_flags & REQ_ELVPRIV) { |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 901 | elv_put_request(rl->q, rq); |
Tejun Heo | f1f8cc9 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 902 | if (rq->elv.icq) |
Tejun Heo | 11a3122 | 2012-02-07 07:51:30 +0100 | [diff] [blame] | 903 | put_io_context(rq->elv.icq->ioc); |
Tejun Heo | f1f8cc9 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 904 | } |
| 905 | |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 906 | mempool_free(rq, rl->rq_pool); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 907 | } |
| 908 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 909 | /* |
| 910 | * ioc_batching returns true if the ioc is a valid batching request and |
| 911 | * should be given priority access to a request. |
| 912 | */ |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 913 | static inline int ioc_batching(struct request_queue *q, struct io_context *ioc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 914 | { |
| 915 | if (!ioc) |
| 916 | return 0; |
| 917 | |
| 918 | /* |
| 919 | * Make sure the process is able to allocate at least 1 request |
| 920 | * even if the batch times out, otherwise we could theoretically |
| 921 | * lose wakeups. |
| 922 | */ |
| 923 | return ioc->nr_batch_requests == q->nr_batching || |
| 924 | (ioc->nr_batch_requests > 0 |
| 925 | && time_before(jiffies, ioc->last_waited + BLK_BATCH_TIME)); |
| 926 | } |
| 927 | |
| 928 | /* |
| 929 | * ioc_set_batching sets ioc to be a new "batcher" if it is not one. This |
| 930 | * will cause the process to be a "batcher" on all queues in the system. This |
| 931 | * is the behaviour we want though - once it gets a wakeup it should be given |
| 932 | * a nice run. |
| 933 | */ |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 934 | static void ioc_set_batching(struct request_queue *q, struct io_context *ioc) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 935 | { |
| 936 | if (!ioc || ioc_batching(q, ioc)) |
| 937 | return; |
| 938 | |
| 939 | ioc->nr_batch_requests = q->nr_batching; |
| 940 | ioc->last_waited = jiffies; |
| 941 | } |
| 942 | |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 943 | static void __freed_request(struct request_list *rl, int sync) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 944 | { |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 945 | struct request_queue *q = rl->q; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 946 | |
Tejun Heo | d40f75a | 2015-05-22 17:13:42 -0400 | [diff] [blame] | 947 | if (rl->count[sync] < queue_congestion_off_threshold(q)) |
| 948 | blk_clear_congested(rl, sync); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 949 | |
Jens Axboe | 1faa16d | 2009-04-06 14:48:01 +0200 | [diff] [blame] | 950 | if (rl->count[sync] + 1 <= q->nr_requests) { |
| 951 | if (waitqueue_active(&rl->wait[sync])) |
| 952 | wake_up(&rl->wait[sync]); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 953 | |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 954 | blk_clear_rl_full(rl, sync); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 955 | } |
| 956 | } |
| 957 | |
| 958 | /* |
| 959 | * A request has just been released. Account for it, update the full and |
| 960 | * congestion status, wake up any waiters. Called under q->queue_lock. |
| 961 | */ |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 962 | static void freed_request(struct request_list *rl, unsigned int flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 963 | { |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 964 | struct request_queue *q = rl->q; |
Tejun Heo | 75eb6c3 | 2011-10-19 14:31:22 +0200 | [diff] [blame] | 965 | int sync = rw_is_sync(flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 966 | |
Tejun Heo | 8a5ecdd | 2012-06-04 20:40:58 -0700 | [diff] [blame] | 967 | q->nr_rqs[sync]--; |
Jens Axboe | 1faa16d | 2009-04-06 14:48:01 +0200 | [diff] [blame] | 968 | rl->count[sync]--; |
Tejun Heo | 75eb6c3 | 2011-10-19 14:31:22 +0200 | [diff] [blame] | 969 | if (flags & REQ_ELVPRIV) |
Tejun Heo | 8a5ecdd | 2012-06-04 20:40:58 -0700 | [diff] [blame] | 970 | q->nr_rqs_elvpriv--; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 971 | |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 972 | __freed_request(rl, sync); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 973 | |
Jens Axboe | 1faa16d | 2009-04-06 14:48:01 +0200 | [diff] [blame] | 974 | if (unlikely(rl->starved[sync ^ 1])) |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 975 | __freed_request(rl, sync ^ 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 976 | } |
| 977 | |
Jens Axboe | e3a2b3f | 2014-05-20 11:49:02 -0600 | [diff] [blame] | 978 | int blk_update_nr_requests(struct request_queue *q, unsigned int nr) |
| 979 | { |
| 980 | struct request_list *rl; |
Tejun Heo | d40f75a | 2015-05-22 17:13:42 -0400 | [diff] [blame] | 981 | int on_thresh, off_thresh; |
Jens Axboe | e3a2b3f | 2014-05-20 11:49:02 -0600 | [diff] [blame] | 982 | |
| 983 | spin_lock_irq(q->queue_lock); |
| 984 | q->nr_requests = nr; |
| 985 | blk_queue_congestion_threshold(q); |
Tejun Heo | d40f75a | 2015-05-22 17:13:42 -0400 | [diff] [blame] | 986 | on_thresh = queue_congestion_on_threshold(q); |
| 987 | off_thresh = queue_congestion_off_threshold(q); |
Jens Axboe | e3a2b3f | 2014-05-20 11:49:02 -0600 | [diff] [blame] | 988 | |
| 989 | blk_queue_for_each_rl(rl, q) { |
Tejun Heo | d40f75a | 2015-05-22 17:13:42 -0400 | [diff] [blame] | 990 | if (rl->count[BLK_RW_SYNC] >= on_thresh) |
| 991 | blk_set_congested(rl, BLK_RW_SYNC); |
| 992 | else if (rl->count[BLK_RW_SYNC] < off_thresh) |
| 993 | blk_clear_congested(rl, BLK_RW_SYNC); |
| 994 | |
| 995 | if (rl->count[BLK_RW_ASYNC] >= on_thresh) |
| 996 | blk_set_congested(rl, BLK_RW_ASYNC); |
| 997 | else if (rl->count[BLK_RW_ASYNC] < off_thresh) |
| 998 | blk_clear_congested(rl, BLK_RW_ASYNC); |
| 999 | |
Jens Axboe | e3a2b3f | 2014-05-20 11:49:02 -0600 | [diff] [blame] | 1000 | if (rl->count[BLK_RW_SYNC] >= q->nr_requests) { |
| 1001 | blk_set_rl_full(rl, BLK_RW_SYNC); |
| 1002 | } else { |
| 1003 | blk_clear_rl_full(rl, BLK_RW_SYNC); |
| 1004 | wake_up(&rl->wait[BLK_RW_SYNC]); |
| 1005 | } |
| 1006 | |
| 1007 | if (rl->count[BLK_RW_ASYNC] >= q->nr_requests) { |
| 1008 | blk_set_rl_full(rl, BLK_RW_ASYNC); |
| 1009 | } else { |
| 1010 | blk_clear_rl_full(rl, BLK_RW_ASYNC); |
| 1011 | wake_up(&rl->wait[BLK_RW_ASYNC]); |
| 1012 | } |
| 1013 | } |
| 1014 | |
| 1015 | spin_unlock_irq(q->queue_lock); |
| 1016 | return 0; |
| 1017 | } |
| 1018 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1019 | /* |
Mike Snitzer | 9d5a4e9 | 2011-02-11 11:05:46 +0100 | [diff] [blame] | 1020 | * Determine if elevator data should be initialized when allocating the |
| 1021 | * request associated with @bio. |
| 1022 | */ |
| 1023 | static bool blk_rq_should_init_elevator(struct bio *bio) |
| 1024 | { |
| 1025 | if (!bio) |
| 1026 | return true; |
| 1027 | |
| 1028 | /* |
| 1029 | * Flush requests do not use the elevator so skip initialization. |
| 1030 | * This allows a request to share the flush and elevator data. |
| 1031 | */ |
| 1032 | if (bio->bi_rw & (REQ_FLUSH | REQ_FUA)) |
| 1033 | return false; |
| 1034 | |
| 1035 | return true; |
| 1036 | } |
| 1037 | |
Tejun Heo | da8303c | 2011-10-19 14:33:05 +0200 | [diff] [blame] | 1038 | /** |
Tejun Heo | 852c788 | 2012-03-05 13:15:27 -0800 | [diff] [blame] | 1039 | * rq_ioc - determine io_context for request allocation |
| 1040 | * @bio: request being allocated is for this bio (can be %NULL) |
| 1041 | * |
| 1042 | * Determine io_context to use for request allocation for @bio. May return |
| 1043 | * %NULL if %current->io_context doesn't exist. |
| 1044 | */ |
| 1045 | static struct io_context *rq_ioc(struct bio *bio) |
| 1046 | { |
| 1047 | #ifdef CONFIG_BLK_CGROUP |
| 1048 | if (bio && bio->bi_ioc) |
| 1049 | return bio->bi_ioc; |
| 1050 | #endif |
| 1051 | return current->io_context; |
| 1052 | } |
| 1053 | |
| 1054 | /** |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1055 | * __get_request - get a free request |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 1056 | * @rl: request list to allocate from |
Tejun Heo | da8303c | 2011-10-19 14:33:05 +0200 | [diff] [blame] | 1057 | * @rw_flags: RW and SYNC flags |
| 1058 | * @bio: bio to allocate request for (can be %NULL) |
| 1059 | * @gfp_mask: allocation mask |
| 1060 | * |
| 1061 | * Get a free request from @q. This function may fail under memory |
| 1062 | * pressure or if @q is dead. |
| 1063 | * |
Masanari Iida | da3dae5 | 2014-09-09 01:27:23 +0900 | [diff] [blame] | 1064 | * Must be called with @q->queue_lock held and, |
Joe Lawrence | a492f07 | 2014-08-28 08:15:21 -0600 | [diff] [blame] | 1065 | * Returns ERR_PTR on failure, with @q->queue_lock held. |
| 1066 | * Returns request pointer on success, with @q->queue_lock *not held*. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1067 | */ |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 1068 | static struct request *__get_request(struct request_list *rl, int rw_flags, |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1069 | struct bio *bio, gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1070 | { |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 1071 | struct request_queue *q = rl->q; |
Tejun Heo | b679281 | 2012-03-05 13:15:23 -0800 | [diff] [blame] | 1072 | struct request *rq; |
Tejun Heo | 7f4b35d | 2012-06-04 20:40:56 -0700 | [diff] [blame] | 1073 | struct elevator_type *et = q->elevator->type; |
| 1074 | struct io_context *ioc = rq_ioc(bio); |
Tejun Heo | f1f8cc9 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 1075 | struct io_cq *icq = NULL; |
Jens Axboe | 1faa16d | 2009-04-06 14:48:01 +0200 | [diff] [blame] | 1076 | const bool is_sync = rw_is_sync(rw_flags) != 0; |
Tejun Heo | 75eb6c3 | 2011-10-19 14:31:22 +0200 | [diff] [blame] | 1077 | int may_queue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1078 | |
Bart Van Assche | 3f3299d | 2012-11-28 13:42:38 +0100 | [diff] [blame] | 1079 | if (unlikely(blk_queue_dying(q))) |
Joe Lawrence | a492f07 | 2014-08-28 08:15:21 -0600 | [diff] [blame] | 1080 | return ERR_PTR(-ENODEV); |
Tejun Heo | da8303c | 2011-10-19 14:33:05 +0200 | [diff] [blame] | 1081 | |
Jens Axboe | 7749a8d | 2006-12-13 13:02:26 +0100 | [diff] [blame] | 1082 | may_queue = elv_may_queue(q, rw_flags); |
Jens Axboe | 88ee5ef | 2005-11-12 11:09:12 +0100 | [diff] [blame] | 1083 | if (may_queue == ELV_MQUEUE_NO) |
| 1084 | goto rq_starved; |
| 1085 | |
Jens Axboe | 1faa16d | 2009-04-06 14:48:01 +0200 | [diff] [blame] | 1086 | if (rl->count[is_sync]+1 >= queue_congestion_on_threshold(q)) { |
| 1087 | if (rl->count[is_sync]+1 >= q->nr_requests) { |
Tejun Heo | f2dbd76 | 2011-12-14 00:33:40 +0100 | [diff] [blame] | 1088 | /* |
Jens Axboe | 88ee5ef | 2005-11-12 11:09:12 +0100 | [diff] [blame] | 1089 | * The queue will fill after this allocation, so set |
| 1090 | * it as full, and mark this process as "batching". |
| 1091 | * This process will be allowed to complete a batch of |
| 1092 | * requests, others will be blocked. |
| 1093 | */ |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 1094 | if (!blk_rl_full(rl, is_sync)) { |
Jens Axboe | 88ee5ef | 2005-11-12 11:09:12 +0100 | [diff] [blame] | 1095 | ioc_set_batching(q, ioc); |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 1096 | blk_set_rl_full(rl, is_sync); |
Jens Axboe | 88ee5ef | 2005-11-12 11:09:12 +0100 | [diff] [blame] | 1097 | } else { |
| 1098 | if (may_queue != ELV_MQUEUE_MUST |
| 1099 | && !ioc_batching(q, ioc)) { |
| 1100 | /* |
| 1101 | * The queue is full and the allocating |
| 1102 | * process is not a "batcher", and not |
| 1103 | * exempted by the IO scheduler |
| 1104 | */ |
Joe Lawrence | a492f07 | 2014-08-28 08:15:21 -0600 | [diff] [blame] | 1105 | return ERR_PTR(-ENOMEM); |
Jens Axboe | 88ee5ef | 2005-11-12 11:09:12 +0100 | [diff] [blame] | 1106 | } |
| 1107 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1108 | } |
Tejun Heo | d40f75a | 2015-05-22 17:13:42 -0400 | [diff] [blame] | 1109 | blk_set_congested(rl, is_sync); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1110 | } |
| 1111 | |
Jens Axboe | 082cf69 | 2005-06-28 16:35:11 +0200 | [diff] [blame] | 1112 | /* |
| 1113 | * Only allow batching queuers to allocate up to 50% over the defined |
| 1114 | * limit of requests, otherwise we could have thousands of requests |
| 1115 | * allocated with any setting of ->nr_requests |
| 1116 | */ |
Jens Axboe | 1faa16d | 2009-04-06 14:48:01 +0200 | [diff] [blame] | 1117 | if (rl->count[is_sync] >= (3 * q->nr_requests / 2)) |
Joe Lawrence | a492f07 | 2014-08-28 08:15:21 -0600 | [diff] [blame] | 1118 | return ERR_PTR(-ENOMEM); |
Hugh Dickins | fd782a4 | 2005-06-29 15:15:40 +0100 | [diff] [blame] | 1119 | |
Tejun Heo | 8a5ecdd | 2012-06-04 20:40:58 -0700 | [diff] [blame] | 1120 | q->nr_rqs[is_sync]++; |
Jens Axboe | 1faa16d | 2009-04-06 14:48:01 +0200 | [diff] [blame] | 1121 | rl->count[is_sync]++; |
| 1122 | rl->starved[is_sync] = 0; |
Tejun Heo | cb98fc8 | 2005-10-28 08:29:39 +0200 | [diff] [blame] | 1123 | |
Tejun Heo | f1f8cc9 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 1124 | /* |
| 1125 | * Decide whether the new request will be managed by elevator. If |
| 1126 | * so, mark @rw_flags and increment elvpriv. Non-zero elvpriv will |
| 1127 | * prevent the current elevator from being destroyed until the new |
| 1128 | * request is freed. This guarantees icq's won't be destroyed and |
| 1129 | * makes creating new ones safe. |
| 1130 | * |
| 1131 | * Also, lookup icq while holding queue_lock. If it doesn't exist, |
| 1132 | * it will be created after releasing queue_lock. |
| 1133 | */ |
Tejun Heo | d732580 | 2012-03-05 13:14:58 -0800 | [diff] [blame] | 1134 | if (blk_rq_should_init_elevator(bio) && !blk_queue_bypass(q)) { |
Tejun Heo | 75eb6c3 | 2011-10-19 14:31:22 +0200 | [diff] [blame] | 1135 | rw_flags |= REQ_ELVPRIV; |
Tejun Heo | 8a5ecdd | 2012-06-04 20:40:58 -0700 | [diff] [blame] | 1136 | q->nr_rqs_elvpriv++; |
Tejun Heo | f1f8cc9 | 2011-12-14 00:33:42 +0100 | [diff] [blame] | 1137 | if (et->icq_cache && ioc) |
| 1138 | icq = ioc_lookup_icq(ioc, q); |
Mike Snitzer | 9d5a4e9 | 2011-02-11 11:05:46 +0100 | [diff] [blame] | 1139 | } |
Tejun Heo | cb98fc8 | 2005-10-28 08:29:39 +0200 | [diff] [blame] | 1140 | |
Jens Axboe | f253b86 | 2010-10-24 22:06:02 +0200 | [diff] [blame] | 1141 | if (blk_queue_io_stat(q)) |
| 1142 | rw_flags |= REQ_IO_STAT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1143 | spin_unlock_irq(q->queue_lock); |
| 1144 | |
Tejun Heo | 29e2b09 | 2012-04-19 16:29:21 -0700 | [diff] [blame] | 1145 | /* allocate and init request */ |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 1146 | rq = mempool_alloc(rl->rq_pool, gfp_mask); |
Tejun Heo | 29e2b09 | 2012-04-19 16:29:21 -0700 | [diff] [blame] | 1147 | if (!rq) |
Tejun Heo | b679281 | 2012-03-05 13:15:23 -0800 | [diff] [blame] | 1148 | goto fail_alloc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1149 | |
Tejun Heo | 29e2b09 | 2012-04-19 16:29:21 -0700 | [diff] [blame] | 1150 | blk_rq_init(q, rq); |
Tejun Heo | a051661 | 2012-06-26 15:05:44 -0700 | [diff] [blame] | 1151 | blk_rq_set_rl(rq, rl); |
Tejun Heo | 29e2b09 | 2012-04-19 16:29:21 -0700 | [diff] [blame] | 1152 | rq->cmd_flags = rw_flags | REQ_ALLOCED; |
| 1153 | |
Tejun Heo | aaf7c68 | 2012-04-19 16:29:22 -0700 | [diff] [blame] | 1154 | /* init elvpriv */ |
Tejun Heo | 29e2b09 | 2012-04-19 16:29:21 -0700 | [diff] [blame] | 1155 | if (rw_flags & REQ_ELVPRIV) { |
Tejun Heo | aaf7c68 | 2012-04-19 16:29:22 -0700 | [diff] [blame] | 1156 | if (unlikely(et->icq_cache && !icq)) { |
Tejun Heo | 7f4b35d | 2012-06-04 20:40:56 -0700 | [diff] [blame] | 1157 | if (ioc) |
| 1158 | icq = ioc_create_icq(ioc, q, gfp_mask); |
Tejun Heo | aaf7c68 | 2012-04-19 16:29:22 -0700 | [diff] [blame] | 1159 | if (!icq) |
| 1160 | goto fail_elvpriv; |
Tejun Heo | 29e2b09 | 2012-04-19 16:29:21 -0700 | [diff] [blame] | 1161 | } |
Tejun Heo | aaf7c68 | 2012-04-19 16:29:22 -0700 | [diff] [blame] | 1162 | |
| 1163 | rq->elv.icq = icq; |
| 1164 | if (unlikely(elv_set_request(q, rq, bio, gfp_mask))) |
| 1165 | goto fail_elvpriv; |
| 1166 | |
| 1167 | /* @rq->elv.icq holds io_context until @rq is freed */ |
Tejun Heo | 29e2b09 | 2012-04-19 16:29:21 -0700 | [diff] [blame] | 1168 | if (icq) |
| 1169 | get_io_context(icq->ioc); |
| 1170 | } |
Tejun Heo | aaf7c68 | 2012-04-19 16:29:22 -0700 | [diff] [blame] | 1171 | out: |
Jens Axboe | 88ee5ef | 2005-11-12 11:09:12 +0100 | [diff] [blame] | 1172 | /* |
| 1173 | * ioc may be NULL here, and ioc_batching will be false. That's |
| 1174 | * OK, if the queue is under the request limit then requests need |
| 1175 | * not count toward the nr_batch_requests limit. There will always |
| 1176 | * be some limit enforced by BLK_BATCH_TIME. |
| 1177 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1178 | if (ioc_batching(q, ioc)) |
| 1179 | ioc->nr_batch_requests--; |
Jens Axboe | 6728cb0 | 2008-01-31 13:03:55 +0100 | [diff] [blame] | 1180 | |
Jens Axboe | 1faa16d | 2009-04-06 14:48:01 +0200 | [diff] [blame] | 1181 | trace_block_getrq(q, bio, rw_flags & 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1182 | return rq; |
Tejun Heo | b679281 | 2012-03-05 13:15:23 -0800 | [diff] [blame] | 1183 | |
Tejun Heo | aaf7c68 | 2012-04-19 16:29:22 -0700 | [diff] [blame] | 1184 | fail_elvpriv: |
| 1185 | /* |
| 1186 | * elvpriv init failed. ioc, icq and elvpriv aren't mempool backed |
| 1187 | * and may fail indefinitely under memory pressure and thus |
| 1188 | * shouldn't stall IO. Treat this request as !elvpriv. This will |
| 1189 | * disturb iosched and blkcg but weird is bettern than dead. |
| 1190 | */ |
Robert Elliott | 7b2b10e | 2014-08-27 10:50:36 -0500 | [diff] [blame] | 1191 | printk_ratelimited(KERN_WARNING "%s: dev %s: request aux data allocation failed, iosched may be disturbed\n", |
| 1192 | __func__, dev_name(q->backing_dev_info.dev)); |
Tejun Heo | aaf7c68 | 2012-04-19 16:29:22 -0700 | [diff] [blame] | 1193 | |
| 1194 | rq->cmd_flags &= ~REQ_ELVPRIV; |
| 1195 | rq->elv.icq = NULL; |
| 1196 | |
| 1197 | spin_lock_irq(q->queue_lock); |
Tejun Heo | 8a5ecdd | 2012-06-04 20:40:58 -0700 | [diff] [blame] | 1198 | q->nr_rqs_elvpriv--; |
Tejun Heo | aaf7c68 | 2012-04-19 16:29:22 -0700 | [diff] [blame] | 1199 | spin_unlock_irq(q->queue_lock); |
| 1200 | goto out; |
| 1201 | |
Tejun Heo | b679281 | 2012-03-05 13:15:23 -0800 | [diff] [blame] | 1202 | fail_alloc: |
| 1203 | /* |
| 1204 | * Allocation failed presumably due to memory. Undo anything we |
| 1205 | * might have messed up. |
| 1206 | * |
| 1207 | * Allocating task should really be put onto the front of the wait |
| 1208 | * queue, but this is pretty rare. |
| 1209 | */ |
| 1210 | spin_lock_irq(q->queue_lock); |
Tejun Heo | 5b788ce | 2012-06-04 20:40:59 -0700 | [diff] [blame] | 1211 | freed_request(rl, rw_flags); |
Tejun Heo | b679281 | 2012-03-05 13:15:23 -0800 | [diff] [blame] | 1212 | |
| 1213 | /* |
| 1214 | * in the very unlikely event that allocation failed and no |
| 1215 | * requests for this direction was pending, mark us starved so that |
| 1216 | * freeing of a request in the other direction will notice |
| 1217 | * us. another possible fix would be to split the rq mempool into |
| 1218 | * READ and WRITE |
| 1219 | */ |
| 1220 | rq_starved: |
| 1221 | if (unlikely(rl->count[is_sync] == 0)) |
| 1222 | rl->starved[is_sync] = 1; |
Joe Lawrence | a492f07 | 2014-08-28 08:15:21 -0600 | [diff] [blame] | 1223 | return ERR_PTR(-ENOMEM); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1224 | } |
| 1225 | |
Tejun Heo | da8303c | 2011-10-19 14:33:05 +0200 | [diff] [blame] | 1226 | /** |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1227 | * get_request - get a free request |
Tejun Heo | da8303c | 2011-10-19 14:33:05 +0200 | [diff] [blame] | 1228 | * @q: request_queue to allocate request from |
| 1229 | * @rw_flags: RW and SYNC flags |
| 1230 | * @bio: bio to allocate request for (can be %NULL) |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1231 | * @gfp_mask: allocation mask |
Nick Piggin | d634453 | 2005-06-28 20:45:14 -0700 | [diff] [blame] | 1232 | * |
Mel Gorman | d0164ad | 2015-11-06 16:28:21 -0800 | [diff] [blame] | 1233 | * Get a free request from @q. If %__GFP_DIRECT_RECLAIM is set in @gfp_mask, |
| 1234 | * this function keeps retrying under memory pressure and fails iff @q is dead. |
Tejun Heo | da8303c | 2011-10-19 14:33:05 +0200 | [diff] [blame] | 1235 | * |
Masanari Iida | da3dae5 | 2014-09-09 01:27:23 +0900 | [diff] [blame] | 1236 | * Must be called with @q->queue_lock held and, |
Joe Lawrence | a492f07 | 2014-08-28 08:15:21 -0600 | [diff] [blame] | 1237 | * Returns ERR_PTR on failure, with @q->queue_lock held. |
| 1238 | * Returns request pointer on success, with @q->queue_lock *not held*. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1239 | */ |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1240 | static struct request *get_request(struct request_queue *q, int rw_flags, |
| 1241 | struct bio *bio, gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1242 | { |
Jens Axboe | 1faa16d | 2009-04-06 14:48:01 +0200 | [diff] [blame] | 1243 | const bool is_sync = rw_is_sync(rw_flags) != 0; |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1244 | DEFINE_WAIT(wait); |
Tejun Heo | a051661 | 2012-06-26 15:05:44 -0700 | [diff] [blame] | 1245 | struct request_list *rl; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1246 | struct request *rq; |
Tejun Heo | a051661 | 2012-06-26 15:05:44 -0700 | [diff] [blame] | 1247 | |
| 1248 | rl = blk_get_rl(q, bio); /* transferred to @rq on success */ |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1249 | retry: |
Tejun Heo | a051661 | 2012-06-26 15:05:44 -0700 | [diff] [blame] | 1250 | rq = __get_request(rl, rw_flags, bio, gfp_mask); |
Joe Lawrence | a492f07 | 2014-08-28 08:15:21 -0600 | [diff] [blame] | 1251 | if (!IS_ERR(rq)) |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1252 | return rq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1253 | |
Mel Gorman | d0164ad | 2015-11-06 16:28:21 -0800 | [diff] [blame] | 1254 | if (!gfpflags_allow_blocking(gfp_mask) || unlikely(blk_queue_dying(q))) { |
Tejun Heo | a051661 | 2012-06-26 15:05:44 -0700 | [diff] [blame] | 1255 | blk_put_rl(rl); |
Joe Lawrence | a492f07 | 2014-08-28 08:15:21 -0600 | [diff] [blame] | 1256 | return rq; |
Tejun Heo | a051661 | 2012-06-26 15:05:44 -0700 | [diff] [blame] | 1257 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1258 | |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1259 | /* wait on @rl and retry */ |
| 1260 | prepare_to_wait_exclusive(&rl->wait[is_sync], &wait, |
| 1261 | TASK_UNINTERRUPTIBLE); |
Tejun Heo | da8303c | 2011-10-19 14:33:05 +0200 | [diff] [blame] | 1262 | |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1263 | trace_block_sleeprq(q, bio, rw_flags & 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1264 | |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1265 | spin_unlock_irq(q->queue_lock); |
| 1266 | io_schedule(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1267 | |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1268 | /* |
| 1269 | * After sleeping, we become a "batching" process and will be able |
| 1270 | * to allocate at least one request, and up to a big batch of them |
| 1271 | * for a small period time. See ioc_batching, ioc_set_batching |
| 1272 | */ |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1273 | ioc_set_batching(q, current->io_context); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1274 | |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1275 | spin_lock_irq(q->queue_lock); |
| 1276 | finish_wait(&rl->wait[is_sync], &wait); |
Jens Axboe | 2056a78 | 2006-03-23 20:00:26 +0100 | [diff] [blame] | 1277 | |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1278 | goto retry; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1279 | } |
| 1280 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1281 | static struct request *blk_old_get_request(struct request_queue *q, int rw, |
| 1282 | gfp_t gfp_mask) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1283 | { |
| 1284 | struct request *rq; |
| 1285 | |
| 1286 | BUG_ON(rw != READ && rw != WRITE); |
| 1287 | |
Tejun Heo | 7f4b35d | 2012-06-04 20:40:56 -0700 | [diff] [blame] | 1288 | /* create ioc upfront */ |
| 1289 | create_io_context(gfp_mask, q->node); |
| 1290 | |
Nick Piggin | d634453 | 2005-06-28 20:45:14 -0700 | [diff] [blame] | 1291 | spin_lock_irq(q->queue_lock); |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1292 | rq = get_request(q, rw, NULL, gfp_mask); |
Joe Lawrence | a492f07 | 2014-08-28 08:15:21 -0600 | [diff] [blame] | 1293 | if (IS_ERR(rq)) |
Tejun Heo | da8303c | 2011-10-19 14:33:05 +0200 | [diff] [blame] | 1294 | spin_unlock_irq(q->queue_lock); |
Nick Piggin | d634453 | 2005-06-28 20:45:14 -0700 | [diff] [blame] | 1295 | /* q->queue_lock is unlocked at this point */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1296 | |
| 1297 | return rq; |
| 1298 | } |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1299 | |
| 1300 | struct request *blk_get_request(struct request_queue *q, int rw, gfp_t gfp_mask) |
| 1301 | { |
| 1302 | if (q->mq_ops) |
Christoph Hellwig | 6f3b0e8 | 2015-11-26 09:13:05 +0100 | [diff] [blame] | 1303 | return blk_mq_alloc_request(q, rw, |
| 1304 | (gfp_mask & __GFP_DIRECT_RECLAIM) ? |
| 1305 | 0 : BLK_MQ_REQ_NOWAIT); |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1306 | else |
| 1307 | return blk_old_get_request(q, rw, gfp_mask); |
| 1308 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1309 | EXPORT_SYMBOL(blk_get_request); |
| 1310 | |
| 1311 | /** |
Boaz Harrosh | 79eb63e | 2009-05-17 18:57:15 +0300 | [diff] [blame] | 1312 | * blk_make_request - given a bio, allocate a corresponding struct request. |
Randy Dunlap | 8ebf975 | 2009-06-11 20:00:41 -0700 | [diff] [blame] | 1313 | * @q: target request queue |
Boaz Harrosh | 79eb63e | 2009-05-17 18:57:15 +0300 | [diff] [blame] | 1314 | * @bio: The bio describing the memory mappings that will be submitted for IO. |
| 1315 | * It may be a chained-bio properly constructed by block/bio layer. |
Randy Dunlap | 8ebf975 | 2009-06-11 20:00:41 -0700 | [diff] [blame] | 1316 | * @gfp_mask: gfp flags to be used for memory allocation |
Jens Axboe | dc72ef4 | 2006-07-20 14:54:05 +0200 | [diff] [blame] | 1317 | * |
Boaz Harrosh | 79eb63e | 2009-05-17 18:57:15 +0300 | [diff] [blame] | 1318 | * blk_make_request is the parallel of generic_make_request for BLOCK_PC |
| 1319 | * type commands. Where the struct request needs to be farther initialized by |
| 1320 | * the caller. It is passed a &struct bio, which describes the memory info of |
| 1321 | * the I/O transfer. |
| 1322 | * |
| 1323 | * The caller of blk_make_request must make sure that bi_io_vec |
| 1324 | * are set to describe the memory buffers. That bio_data_dir() will return |
| 1325 | * the needed direction of the request. (And all bio's in the passed bio-chain |
| 1326 | * are properly set accordingly) |
| 1327 | * |
| 1328 | * If called under none-sleepable conditions, mapped bio buffers must not |
| 1329 | * need bouncing, by calling the appropriate masked or flagged allocator, |
| 1330 | * suitable for the target device. Otherwise the call to blk_queue_bounce will |
| 1331 | * BUG. |
Jens Axboe | 53674ac | 2009-05-19 19:52:35 +0200 | [diff] [blame] | 1332 | * |
| 1333 | * WARNING: When allocating/cloning a bio-chain, careful consideration should be |
Mel Gorman | d0164ad | 2015-11-06 16:28:21 -0800 | [diff] [blame] | 1334 | * given to how you allocate bios. In particular, you cannot use |
| 1335 | * __GFP_DIRECT_RECLAIM for anything but the first bio in the chain. Otherwise |
| 1336 | * you risk waiting for IO completion of a bio that hasn't been submitted yet, |
| 1337 | * thus resulting in a deadlock. Alternatively bios should be allocated using |
| 1338 | * bio_kmalloc() instead of bio_alloc(), as that avoids the mempool deadlock. |
Jens Axboe | 53674ac | 2009-05-19 19:52:35 +0200 | [diff] [blame] | 1339 | * If possible a big IO should be split into smaller parts when allocation |
| 1340 | * fails. Partial allocation should not be an error, or you risk a live-lock. |
Jens Axboe | dc72ef4 | 2006-07-20 14:54:05 +0200 | [diff] [blame] | 1341 | */ |
Boaz Harrosh | 79eb63e | 2009-05-17 18:57:15 +0300 | [diff] [blame] | 1342 | struct request *blk_make_request(struct request_queue *q, struct bio *bio, |
| 1343 | gfp_t gfp_mask) |
Jens Axboe | dc72ef4 | 2006-07-20 14:54:05 +0200 | [diff] [blame] | 1344 | { |
Boaz Harrosh | 79eb63e | 2009-05-17 18:57:15 +0300 | [diff] [blame] | 1345 | struct request *rq = blk_get_request(q, bio_data_dir(bio), gfp_mask); |
| 1346 | |
Joe Lawrence | a492f07 | 2014-08-28 08:15:21 -0600 | [diff] [blame] | 1347 | if (IS_ERR(rq)) |
| 1348 | return rq; |
Boaz Harrosh | 79eb63e | 2009-05-17 18:57:15 +0300 | [diff] [blame] | 1349 | |
Jens Axboe | f27b087 | 2014-06-06 07:57:37 -0600 | [diff] [blame] | 1350 | blk_rq_set_block_pc(rq); |
| 1351 | |
Boaz Harrosh | 79eb63e | 2009-05-17 18:57:15 +0300 | [diff] [blame] | 1352 | for_each_bio(bio) { |
| 1353 | struct bio *bounce_bio = bio; |
| 1354 | int ret; |
| 1355 | |
| 1356 | blk_queue_bounce(q, &bounce_bio); |
| 1357 | ret = blk_rq_append_bio(q, rq, bounce_bio); |
| 1358 | if (unlikely(ret)) { |
| 1359 | blk_put_request(rq); |
| 1360 | return ERR_PTR(ret); |
| 1361 | } |
| 1362 | } |
| 1363 | |
| 1364 | return rq; |
Jens Axboe | dc72ef4 | 2006-07-20 14:54:05 +0200 | [diff] [blame] | 1365 | } |
Boaz Harrosh | 79eb63e | 2009-05-17 18:57:15 +0300 | [diff] [blame] | 1366 | EXPORT_SYMBOL(blk_make_request); |
Jens Axboe | dc72ef4 | 2006-07-20 14:54:05 +0200 | [diff] [blame] | 1367 | |
| 1368 | /** |
Masanari Iida | da3dae5 | 2014-09-09 01:27:23 +0900 | [diff] [blame] | 1369 | * blk_rq_set_block_pc - initialize a request to type BLOCK_PC |
Jens Axboe | f27b087 | 2014-06-06 07:57:37 -0600 | [diff] [blame] | 1370 | * @rq: request to be initialized |
| 1371 | * |
| 1372 | */ |
| 1373 | void blk_rq_set_block_pc(struct request *rq) |
| 1374 | { |
| 1375 | rq->cmd_type = REQ_TYPE_BLOCK_PC; |
| 1376 | rq->__data_len = 0; |
| 1377 | rq->__sector = (sector_t) -1; |
| 1378 | rq->bio = rq->biotail = NULL; |
| 1379 | memset(rq->__cmd, 0, sizeof(rq->__cmd)); |
Jens Axboe | f27b087 | 2014-06-06 07:57:37 -0600 | [diff] [blame] | 1380 | } |
| 1381 | EXPORT_SYMBOL(blk_rq_set_block_pc); |
| 1382 | |
| 1383 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1384 | * blk_requeue_request - put a request back on queue |
| 1385 | * @q: request queue where request should be inserted |
| 1386 | * @rq: request to be inserted |
| 1387 | * |
| 1388 | * Description: |
| 1389 | * Drivers often keep queueing requests until the hardware cannot accept |
| 1390 | * more, when that condition happens we need to put the request back |
| 1391 | * on the queue. Must be called with queue lock held. |
| 1392 | */ |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1393 | void blk_requeue_request(struct request_queue *q, struct request *rq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1394 | { |
Jens Axboe | 242f9dc | 2008-09-14 05:55:09 -0700 | [diff] [blame] | 1395 | blk_delete_timer(rq); |
| 1396 | blk_clear_rq_complete(rq); |
Arnaldo Carvalho de Melo | 5f3ea37 | 2008-10-30 08:34:33 +0100 | [diff] [blame] | 1397 | trace_block_rq_requeue(q, rq); |
Jens Axboe | 2056a78 | 2006-03-23 20:00:26 +0100 | [diff] [blame] | 1398 | |
Christoph Hellwig | 125c99b | 2014-11-03 12:47:47 +0100 | [diff] [blame] | 1399 | if (rq->cmd_flags & REQ_QUEUED) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1400 | blk_queue_end_tag(q, rq); |
| 1401 | |
James Bottomley | ba396a6 | 2009-05-27 14:17:08 +0200 | [diff] [blame] | 1402 | BUG_ON(blk_queued_rq(rq)); |
| 1403 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1404 | elv_requeue_request(q, rq); |
| 1405 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1406 | EXPORT_SYMBOL(blk_requeue_request); |
| 1407 | |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1408 | static void add_acct_request(struct request_queue *q, struct request *rq, |
| 1409 | int where) |
| 1410 | { |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1411 | blk_account_io_start(rq, true); |
Jens Axboe | 7eaceac | 2011-03-10 08:52:07 +0100 | [diff] [blame] | 1412 | __elv_add_request(q, rq, where); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1413 | } |
| 1414 | |
Tejun Heo | 074a7ac | 2008-08-25 19:56:14 +0900 | [diff] [blame] | 1415 | static void part_round_stats_single(int cpu, struct hd_struct *part, |
| 1416 | unsigned long now) |
| 1417 | { |
Jens Axboe | 7276d02 | 2014-05-09 15:48:23 -0600 | [diff] [blame] | 1418 | int inflight; |
| 1419 | |
Tejun Heo | 074a7ac | 2008-08-25 19:56:14 +0900 | [diff] [blame] | 1420 | if (now == part->stamp) |
| 1421 | return; |
| 1422 | |
Jens Axboe | 7276d02 | 2014-05-09 15:48:23 -0600 | [diff] [blame] | 1423 | inflight = part_in_flight(part); |
| 1424 | if (inflight) { |
Tejun Heo | 074a7ac | 2008-08-25 19:56:14 +0900 | [diff] [blame] | 1425 | __part_stat_add(cpu, part, time_in_queue, |
Jens Axboe | 7276d02 | 2014-05-09 15:48:23 -0600 | [diff] [blame] | 1426 | inflight * (now - part->stamp)); |
Tejun Heo | 074a7ac | 2008-08-25 19:56:14 +0900 | [diff] [blame] | 1427 | __part_stat_add(cpu, part, io_ticks, (now - part->stamp)); |
| 1428 | } |
| 1429 | part->stamp = now; |
| 1430 | } |
| 1431 | |
| 1432 | /** |
Randy Dunlap | 496aa8a | 2008-10-16 07:46:23 +0200 | [diff] [blame] | 1433 | * part_round_stats() - Round off the performance stats on a struct disk_stats. |
| 1434 | * @cpu: cpu number for stats access |
| 1435 | * @part: target partition |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1436 | * |
| 1437 | * The average IO queue length and utilisation statistics are maintained |
| 1438 | * by observing the current state of the queue length and the amount of |
| 1439 | * time it has been in this state for. |
| 1440 | * |
| 1441 | * Normally, that accounting is done on IO completion, but that can result |
| 1442 | * in more than a second's worth of IO being accounted for within any one |
| 1443 | * second, leading to >100% utilisation. To deal with that, we call this |
| 1444 | * function to do a round-off before returning the results when reading |
| 1445 | * /proc/diskstats. This accounts immediately for all queue usage up to |
| 1446 | * the current jiffies and restarts the counters again. |
| 1447 | */ |
Tejun Heo | c995905 | 2008-08-25 19:47:21 +0900 | [diff] [blame] | 1448 | void part_round_stats(int cpu, struct hd_struct *part) |
Jerome Marchand | 6f2576a | 2008-02-08 11:04:35 +0100 | [diff] [blame] | 1449 | { |
| 1450 | unsigned long now = jiffies; |
| 1451 | |
Tejun Heo | 074a7ac | 2008-08-25 19:56:14 +0900 | [diff] [blame] | 1452 | if (part->partno) |
| 1453 | part_round_stats_single(cpu, &part_to_disk(part)->part0, now); |
| 1454 | part_round_stats_single(cpu, part, now); |
Jerome Marchand | 6f2576a | 2008-02-08 11:04:35 +0100 | [diff] [blame] | 1455 | } |
Tejun Heo | 074a7ac | 2008-08-25 19:56:14 +0900 | [diff] [blame] | 1456 | EXPORT_SYMBOL_GPL(part_round_stats); |
Jerome Marchand | 6f2576a | 2008-02-08 11:04:35 +0100 | [diff] [blame] | 1457 | |
Rafael J. Wysocki | 47fafbc | 2014-12-04 01:00:23 +0100 | [diff] [blame] | 1458 | #ifdef CONFIG_PM |
Lin Ming | c815881 | 2013-03-23 11:42:27 +0800 | [diff] [blame] | 1459 | static void blk_pm_put_request(struct request *rq) |
| 1460 | { |
| 1461 | if (rq->q->dev && !(rq->cmd_flags & REQ_PM) && !--rq->q->nr_pending) |
| 1462 | pm_runtime_mark_last_busy(rq->q->dev); |
| 1463 | } |
| 1464 | #else |
| 1465 | static inline void blk_pm_put_request(struct request *rq) {} |
| 1466 | #endif |
| 1467 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1468 | /* |
| 1469 | * queue lock must be held |
| 1470 | */ |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1471 | void __blk_put_request(struct request_queue *q, struct request *req) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1472 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1473 | if (unlikely(!q)) |
| 1474 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1475 | |
Christoph Hellwig | 6f5ba58 | 2014-02-07 10:22:37 -0800 | [diff] [blame] | 1476 | if (q->mq_ops) { |
| 1477 | blk_mq_free_request(req); |
| 1478 | return; |
| 1479 | } |
| 1480 | |
Lin Ming | c815881 | 2013-03-23 11:42:27 +0800 | [diff] [blame] | 1481 | blk_pm_put_request(req); |
| 1482 | |
Tejun Heo | 8922e16 | 2005-10-20 16:23:44 +0200 | [diff] [blame] | 1483 | elv_completed_request(q, req); |
| 1484 | |
Boaz Harrosh | 1cd96c2 | 2009-03-24 12:35:07 +0100 | [diff] [blame] | 1485 | /* this is a bio leak */ |
| 1486 | WARN_ON(req->bio != NULL); |
| 1487 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1488 | /* |
| 1489 | * Request may not have originated from ll_rw_blk. if not, |
| 1490 | * it didn't come out of our reserved rq pools |
| 1491 | */ |
Jens Axboe | 49171e5 | 2006-08-10 08:59:11 +0200 | [diff] [blame] | 1492 | if (req->cmd_flags & REQ_ALLOCED) { |
Tejun Heo | 75eb6c3 | 2011-10-19 14:31:22 +0200 | [diff] [blame] | 1493 | unsigned int flags = req->cmd_flags; |
Tejun Heo | a051661 | 2012-06-26 15:05:44 -0700 | [diff] [blame] | 1494 | struct request_list *rl = blk_rq_rl(req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1495 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1496 | BUG_ON(!list_empty(&req->queuelist)); |
Jens Axboe | 360f92c | 2014-04-09 20:27:01 -0600 | [diff] [blame] | 1497 | BUG_ON(ELV_ON_HASH(req)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1498 | |
Tejun Heo | a051661 | 2012-06-26 15:05:44 -0700 | [diff] [blame] | 1499 | blk_free_request(rl, req); |
| 1500 | freed_request(rl, flags); |
| 1501 | blk_put_rl(rl); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1502 | } |
| 1503 | } |
Mike Christie | 6e39b69 | 2005-11-11 05:30:24 -0600 | [diff] [blame] | 1504 | EXPORT_SYMBOL_GPL(__blk_put_request); |
| 1505 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1506 | void blk_put_request(struct request *req) |
| 1507 | { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1508 | struct request_queue *q = req->q; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1509 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1510 | if (q->mq_ops) |
| 1511 | blk_mq_free_request(req); |
| 1512 | else { |
| 1513 | unsigned long flags; |
| 1514 | |
| 1515 | spin_lock_irqsave(q->queue_lock, flags); |
| 1516 | __blk_put_request(q, req); |
| 1517 | spin_unlock_irqrestore(q->queue_lock, flags); |
| 1518 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1519 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1520 | EXPORT_SYMBOL(blk_put_request); |
| 1521 | |
Christoph Hellwig | 66ac028 | 2010-06-18 16:59:42 +0200 | [diff] [blame] | 1522 | /** |
| 1523 | * blk_add_request_payload - add a payload to a request |
| 1524 | * @rq: request to update |
| 1525 | * @page: page backing the payload |
| 1526 | * @len: length of the payload. |
| 1527 | * |
| 1528 | * This allows to later add a payload to an already submitted request by |
| 1529 | * a block driver. The driver needs to take care of freeing the payload |
| 1530 | * itself. |
| 1531 | * |
| 1532 | * Note that this is a quite horrible hack and nothing but handling of |
| 1533 | * discard requests should ever use it. |
| 1534 | */ |
| 1535 | void blk_add_request_payload(struct request *rq, struct page *page, |
| 1536 | unsigned int len) |
| 1537 | { |
| 1538 | struct bio *bio = rq->bio; |
| 1539 | |
| 1540 | bio->bi_io_vec->bv_page = page; |
| 1541 | bio->bi_io_vec->bv_offset = 0; |
| 1542 | bio->bi_io_vec->bv_len = len; |
| 1543 | |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1544 | bio->bi_iter.bi_size = len; |
Christoph Hellwig | 66ac028 | 2010-06-18 16:59:42 +0200 | [diff] [blame] | 1545 | bio->bi_vcnt = 1; |
| 1546 | bio->bi_phys_segments = 1; |
| 1547 | |
| 1548 | rq->__data_len = rq->resid_len = len; |
| 1549 | rq->nr_phys_segments = 1; |
Christoph Hellwig | 66ac028 | 2010-06-18 16:59:42 +0200 | [diff] [blame] | 1550 | } |
| 1551 | EXPORT_SYMBOL_GPL(blk_add_request_payload); |
| 1552 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1553 | bool bio_attempt_back_merge(struct request_queue *q, struct request *req, |
| 1554 | struct bio *bio) |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1555 | { |
| 1556 | const int ff = bio->bi_rw & REQ_FAILFAST_MASK; |
| 1557 | |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1558 | if (!ll_back_merge_fn(q, req, bio)) |
| 1559 | return false; |
| 1560 | |
Tejun Heo | 8c1cf6b | 2013-01-11 13:06:34 -0800 | [diff] [blame] | 1561 | trace_block_bio_backmerge(q, req, bio); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1562 | |
| 1563 | if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff) |
| 1564 | blk_rq_set_mixed_merge(req); |
| 1565 | |
| 1566 | req->biotail->bi_next = bio; |
| 1567 | req->biotail = bio; |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1568 | req->__data_len += bio->bi_iter.bi_size; |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1569 | req->ioprio = ioprio_best(req->ioprio, bio_prio(bio)); |
| 1570 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1571 | blk_account_io_start(req, false); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1572 | return true; |
| 1573 | } |
| 1574 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1575 | bool bio_attempt_front_merge(struct request_queue *q, struct request *req, |
| 1576 | struct bio *bio) |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1577 | { |
| 1578 | const int ff = bio->bi_rw & REQ_FAILFAST_MASK; |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1579 | |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1580 | if (!ll_front_merge_fn(q, req, bio)) |
| 1581 | return false; |
| 1582 | |
Tejun Heo | 8c1cf6b | 2013-01-11 13:06:34 -0800 | [diff] [blame] | 1583 | trace_block_bio_frontmerge(q, req, bio); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1584 | |
| 1585 | if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff) |
| 1586 | blk_rq_set_mixed_merge(req); |
| 1587 | |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1588 | bio->bi_next = req->bio; |
| 1589 | req->bio = bio; |
| 1590 | |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1591 | req->__sector = bio->bi_iter.bi_sector; |
| 1592 | req->__data_len += bio->bi_iter.bi_size; |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1593 | req->ioprio = ioprio_best(req->ioprio, bio_prio(bio)); |
| 1594 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1595 | blk_account_io_start(req, false); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1596 | return true; |
| 1597 | } |
| 1598 | |
Tejun Heo | bd87b58 | 2011-10-19 14:33:08 +0200 | [diff] [blame] | 1599 | /** |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1600 | * blk_attempt_plug_merge - try to merge with %current's plugged list |
Tejun Heo | bd87b58 | 2011-10-19 14:33:08 +0200 | [diff] [blame] | 1601 | * @q: request_queue new bio is being queued at |
| 1602 | * @bio: new bio being queued |
| 1603 | * @request_count: out parameter for number of traversed plugged requests |
Randy Dunlap | ccc2600 | 2015-10-30 18:36:16 -0700 | [diff] [blame] | 1604 | * @same_queue_rq: pointer to &struct request that gets filled in when |
| 1605 | * another request associated with @q is found on the plug list |
| 1606 | * (optional, may be %NULL) |
Tejun Heo | bd87b58 | 2011-10-19 14:33:08 +0200 | [diff] [blame] | 1607 | * |
| 1608 | * Determine whether @bio being queued on @q can be merged with a request |
| 1609 | * on %current's plugged list. Returns %true if merge was successful, |
| 1610 | * otherwise %false. |
| 1611 | * |
Tejun Heo | 07c2bd3 | 2012-02-08 09:19:42 +0100 | [diff] [blame] | 1612 | * Plugging coalesces IOs from the same issuer for the same purpose without |
| 1613 | * going through @q->queue_lock. As such it's more of an issuing mechanism |
| 1614 | * than scheduling, and the request, while may have elvpriv data, is not |
| 1615 | * added on the elevator at this point. In addition, we don't have |
| 1616 | * reliable access to the elevator outside queue lock. Only check basic |
| 1617 | * merging parameters without querying the elevator. |
Robert Elliott | da41a58 | 2014-05-20 16:46:26 -0500 | [diff] [blame] | 1618 | * |
| 1619 | * Caller must ensure !blk_queue_nomerges(q) beforehand. |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1620 | */ |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1621 | bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio, |
Shaohua Li | 5b3f341 | 2015-05-08 10:51:33 -0700 | [diff] [blame] | 1622 | unsigned int *request_count, |
| 1623 | struct request **same_queue_rq) |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1624 | { |
| 1625 | struct blk_plug *plug; |
| 1626 | struct request *rq; |
| 1627 | bool ret = false; |
Shaohua Li | 92f399c | 2013-10-29 12:01:03 -0600 | [diff] [blame] | 1628 | struct list_head *plug_list; |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1629 | |
Tejun Heo | bd87b58 | 2011-10-19 14:33:08 +0200 | [diff] [blame] | 1630 | plug = current->plug; |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1631 | if (!plug) |
| 1632 | goto out; |
Shaohua Li | 56ebdaf | 2011-08-24 16:04:34 +0200 | [diff] [blame] | 1633 | *request_count = 0; |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1634 | |
Shaohua Li | 92f399c | 2013-10-29 12:01:03 -0600 | [diff] [blame] | 1635 | if (q->mq_ops) |
| 1636 | plug_list = &plug->mq_list; |
| 1637 | else |
| 1638 | plug_list = &plug->list; |
| 1639 | |
| 1640 | list_for_each_entry_reverse(rq, plug_list, queuelist) { |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1641 | int el_ret; |
| 1642 | |
Shaohua Li | 5b3f341 | 2015-05-08 10:51:33 -0700 | [diff] [blame] | 1643 | if (rq->q == q) { |
Shaohua Li | 1b2e19f | 2012-04-06 11:37:47 -0600 | [diff] [blame] | 1644 | (*request_count)++; |
Shaohua Li | 5b3f341 | 2015-05-08 10:51:33 -0700 | [diff] [blame] | 1645 | /* |
| 1646 | * Only blk-mq multiple hardware queues case checks the |
| 1647 | * rq in the same queue, there should be only one such |
| 1648 | * rq in a queue |
| 1649 | **/ |
| 1650 | if (same_queue_rq) |
| 1651 | *same_queue_rq = rq; |
| 1652 | } |
Shaohua Li | 56ebdaf | 2011-08-24 16:04:34 +0200 | [diff] [blame] | 1653 | |
Tejun Heo | 07c2bd3 | 2012-02-08 09:19:42 +0100 | [diff] [blame] | 1654 | if (rq->q != q || !blk_rq_merge_ok(rq, bio)) |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1655 | continue; |
| 1656 | |
Tejun Heo | 050c8ea | 2012-02-08 09:19:38 +0100 | [diff] [blame] | 1657 | el_ret = blk_try_merge(rq, bio); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1658 | if (el_ret == ELEVATOR_BACK_MERGE) { |
| 1659 | ret = bio_attempt_back_merge(q, rq, bio); |
| 1660 | if (ret) |
| 1661 | break; |
| 1662 | } else if (el_ret == ELEVATOR_FRONT_MERGE) { |
| 1663 | ret = bio_attempt_front_merge(q, rq, bio); |
| 1664 | if (ret) |
| 1665 | break; |
| 1666 | } |
| 1667 | } |
| 1668 | out: |
| 1669 | return ret; |
| 1670 | } |
| 1671 | |
Jeff Moyer | 0809e3a | 2015-10-20 23:13:51 +0800 | [diff] [blame] | 1672 | unsigned int blk_plug_queued_count(struct request_queue *q) |
| 1673 | { |
| 1674 | struct blk_plug *plug; |
| 1675 | struct request *rq; |
| 1676 | struct list_head *plug_list; |
| 1677 | unsigned int ret = 0; |
| 1678 | |
| 1679 | plug = current->plug; |
| 1680 | if (!plug) |
| 1681 | goto out; |
| 1682 | |
| 1683 | if (q->mq_ops) |
| 1684 | plug_list = &plug->mq_list; |
| 1685 | else |
| 1686 | plug_list = &plug->list; |
| 1687 | |
| 1688 | list_for_each_entry(rq, plug_list, queuelist) { |
| 1689 | if (rq->q == q) |
| 1690 | ret++; |
| 1691 | } |
| 1692 | out: |
| 1693 | return ret; |
| 1694 | } |
| 1695 | |
Jens Axboe | 86db1e2 | 2008-01-29 14:53:40 +0100 | [diff] [blame] | 1696 | void init_request_from_bio(struct request *req, struct bio *bio) |
Tejun Heo | 52d9e67 | 2006-01-06 09:49:58 +0100 | [diff] [blame] | 1697 | { |
Jens Axboe | 4aff5e2 | 2006-08-10 08:44:47 +0200 | [diff] [blame] | 1698 | req->cmd_type = REQ_TYPE_FS; |
Tejun Heo | 52d9e67 | 2006-01-06 09:49:58 +0100 | [diff] [blame] | 1699 | |
Christoph Hellwig | 7b6d91d | 2010-08-07 18:20:39 +0200 | [diff] [blame] | 1700 | req->cmd_flags |= bio->bi_rw & REQ_COMMON_MASK; |
| 1701 | if (bio->bi_rw & REQ_RAHEAD) |
Tejun Heo | a82afdf | 2009-07-03 17:48:16 +0900 | [diff] [blame] | 1702 | req->cmd_flags |= REQ_FAILFAST_MASK; |
Jens Axboe | b31dc66 | 2006-06-13 08:26:10 +0200 | [diff] [blame] | 1703 | |
Tejun Heo | 52d9e67 | 2006-01-06 09:49:58 +0100 | [diff] [blame] | 1704 | req->errors = 0; |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1705 | req->__sector = bio->bi_iter.bi_sector; |
Tejun Heo | 52d9e67 | 2006-01-06 09:49:58 +0100 | [diff] [blame] | 1706 | req->ioprio = bio_prio(bio); |
NeilBrown | bc1c56f | 2007-08-16 13:31:30 +0200 | [diff] [blame] | 1707 | blk_rq_bio_prep(req->q, req, bio); |
Tejun Heo | 52d9e67 | 2006-01-06 09:49:58 +0100 | [diff] [blame] | 1708 | } |
| 1709 | |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 1710 | static blk_qc_t blk_queue_bio(struct request_queue *q, struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1711 | { |
Jiri Slaby | 5e00d1b | 2010-08-12 14:31:06 +0200 | [diff] [blame] | 1712 | const bool sync = !!(bio->bi_rw & REQ_SYNC); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1713 | struct blk_plug *plug; |
| 1714 | int el_ret, rw_flags, where = ELEVATOR_INSERT_SORT; |
| 1715 | struct request *req; |
Shaohua Li | 56ebdaf | 2011-08-24 16:04:34 +0200 | [diff] [blame] | 1716 | unsigned int request_count = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1717 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1718 | /* |
| 1719 | * low level driver can indicate that it wants pages above a |
| 1720 | * certain limit bounced to low memory (ie for highmem, or even |
| 1721 | * ISA dma in theory) |
| 1722 | */ |
| 1723 | blk_queue_bounce(q, &bio); |
| 1724 | |
Junichi Nomura | 23688bf | 2015-12-22 10:23:44 -0700 | [diff] [blame] | 1725 | blk_queue_split(q, &bio, q->bio_split); |
| 1726 | |
Darrick J. Wong | ffecfd1 | 2013-02-21 16:42:55 -0800 | [diff] [blame] | 1727 | if (bio_integrity_enabled(bio) && bio_integrity_prep(bio)) { |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1728 | bio->bi_error = -EIO; |
| 1729 | bio_endio(bio); |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 1730 | return BLK_QC_T_NONE; |
Darrick J. Wong | ffecfd1 | 2013-02-21 16:42:55 -0800 | [diff] [blame] | 1731 | } |
| 1732 | |
Tejun Heo | 4fed947 | 2010-09-03 11:56:17 +0200 | [diff] [blame] | 1733 | if (bio->bi_rw & (REQ_FLUSH | REQ_FUA)) { |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1734 | spin_lock_irq(q->queue_lock); |
Tejun Heo | ae1b153 | 2011-01-25 12:43:54 +0100 | [diff] [blame] | 1735 | where = ELEVATOR_INSERT_FLUSH; |
Tejun Heo | 28e7d18 | 2010-09-03 11:56:16 +0200 | [diff] [blame] | 1736 | goto get_rq; |
| 1737 | } |
| 1738 | |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1739 | /* |
| 1740 | * Check if we can merge with the plugged list before grabbing |
| 1741 | * any locks. |
| 1742 | */ |
Jeff Moyer | 0809e3a | 2015-10-20 23:13:51 +0800 | [diff] [blame] | 1743 | if (!blk_queue_nomerges(q)) { |
| 1744 | if (blk_attempt_plug_merge(q, bio, &request_count, NULL)) |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 1745 | return BLK_QC_T_NONE; |
Jeff Moyer | 0809e3a | 2015-10-20 23:13:51 +0800 | [diff] [blame] | 1746 | } else |
| 1747 | request_count = blk_plug_queued_count(q); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1748 | |
| 1749 | spin_lock_irq(q->queue_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1750 | |
| 1751 | el_ret = elv_merge(q, &req, bio); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1752 | if (el_ret == ELEVATOR_BACK_MERGE) { |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1753 | if (bio_attempt_back_merge(q, req, bio)) { |
Tejun Heo | 07c2bd3 | 2012-02-08 09:19:42 +0100 | [diff] [blame] | 1754 | elv_bio_merged(q, req, bio); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1755 | if (!attempt_back_merge(q, req)) |
| 1756 | elv_merged_request(q, req, el_ret); |
| 1757 | goto out_unlock; |
Tejun Heo | 80a761f | 2009-07-03 17:48:17 +0900 | [diff] [blame] | 1758 | } |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1759 | } else if (el_ret == ELEVATOR_FRONT_MERGE) { |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1760 | if (bio_attempt_front_merge(q, req, bio)) { |
Tejun Heo | 07c2bd3 | 2012-02-08 09:19:42 +0100 | [diff] [blame] | 1761 | elv_bio_merged(q, req, bio); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1762 | if (!attempt_front_merge(q, req)) |
| 1763 | elv_merged_request(q, req, el_ret); |
| 1764 | goto out_unlock; |
| 1765 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1766 | } |
| 1767 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1768 | get_rq: |
Nick Piggin | 450991b | 2005-06-28 20:45:13 -0700 | [diff] [blame] | 1769 | /* |
Jens Axboe | 7749a8d | 2006-12-13 13:02:26 +0100 | [diff] [blame] | 1770 | * This sync check and mask will be re-done in init_request_from_bio(), |
| 1771 | * but we need to set it earlier to expose the sync flag to the |
| 1772 | * rq allocator and io schedulers. |
| 1773 | */ |
| 1774 | rw_flags = bio_data_dir(bio); |
| 1775 | if (sync) |
Christoph Hellwig | 7b6d91d | 2010-08-07 18:20:39 +0200 | [diff] [blame] | 1776 | rw_flags |= REQ_SYNC; |
Jens Axboe | 7749a8d | 2006-12-13 13:02:26 +0100 | [diff] [blame] | 1777 | |
| 1778 | /* |
Nick Piggin | 450991b | 2005-06-28 20:45:13 -0700 | [diff] [blame] | 1779 | * Grab a free request. This is might sleep but can not fail. |
Nick Piggin | d634453 | 2005-06-28 20:45:14 -0700 | [diff] [blame] | 1780 | * Returns with the queue unlocked. |
Nick Piggin | 450991b | 2005-06-28 20:45:13 -0700 | [diff] [blame] | 1781 | */ |
Tejun Heo | a06e05e | 2012-06-04 20:40:55 -0700 | [diff] [blame] | 1782 | req = get_request(q, rw_flags, bio, GFP_NOIO); |
Joe Lawrence | a492f07 | 2014-08-28 08:15:21 -0600 | [diff] [blame] | 1783 | if (IS_ERR(req)) { |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 1784 | bio->bi_error = PTR_ERR(req); |
| 1785 | bio_endio(bio); |
Tejun Heo | da8303c | 2011-10-19 14:33:05 +0200 | [diff] [blame] | 1786 | goto out_unlock; |
| 1787 | } |
Nick Piggin | d634453 | 2005-06-28 20:45:14 -0700 | [diff] [blame] | 1788 | |
Nick Piggin | 450991b | 2005-06-28 20:45:13 -0700 | [diff] [blame] | 1789 | /* |
| 1790 | * After dropping the lock and possibly sleeping here, our request |
| 1791 | * may now be mergeable after it had proven unmergeable (above). |
| 1792 | * We don't worry about that case for efficiency. It won't happen |
| 1793 | * often, and the elevators are able to handle it. |
| 1794 | */ |
Tejun Heo | 52d9e67 | 2006-01-06 09:49:58 +0100 | [diff] [blame] | 1795 | init_request_from_bio(req, bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1796 | |
Tao Ma | 9562ad9 | 2011-10-24 16:11:30 +0200 | [diff] [blame] | 1797 | if (test_bit(QUEUE_FLAG_SAME_COMP, &q->queue_flags)) |
Jens Axboe | 11ccf11 | 2011-07-26 15:01:15 +0200 | [diff] [blame] | 1798 | req->cpu = raw_smp_processor_id(); |
Tejun Heo | dd83100 | 2010-09-03 11:56:16 +0200 | [diff] [blame] | 1799 | |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1800 | plug = current->plug; |
Jens Axboe | 721a960 | 2011-03-09 11:56:30 +0100 | [diff] [blame] | 1801 | if (plug) { |
Jens Axboe | dc6d36c | 2011-04-12 10:28:28 +0200 | [diff] [blame] | 1802 | /* |
| 1803 | * If this is the first request added after a plug, fire |
Jianpeng Ma | 7aef2e7 | 2013-09-11 13:21:07 -0600 | [diff] [blame] | 1804 | * of a plug trace. |
Jens Axboe | dc6d36c | 2011-04-12 10:28:28 +0200 | [diff] [blame] | 1805 | */ |
Jianpeng Ma | 7aef2e7 | 2013-09-11 13:21:07 -0600 | [diff] [blame] | 1806 | if (!request_count) |
Jens Axboe | dc6d36c | 2011-04-12 10:28:28 +0200 | [diff] [blame] | 1807 | trace_block_plug(q); |
Shaohua Li | 3540d5e | 2011-11-16 09:21:50 +0100 | [diff] [blame] | 1808 | else { |
Shaohua Li | 019ceb7 | 2011-11-16 09:21:50 +0100 | [diff] [blame] | 1809 | if (request_count >= BLK_MAX_REQUEST_COUNT) { |
Shaohua Li | 3540d5e | 2011-11-16 09:21:50 +0100 | [diff] [blame] | 1810 | blk_flush_plug_list(plug, false); |
Shaohua Li | 019ceb7 | 2011-11-16 09:21:50 +0100 | [diff] [blame] | 1811 | trace_block_plug(q); |
| 1812 | } |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1813 | } |
Shaohua Li | a632716 | 2011-08-24 16:04:32 +0200 | [diff] [blame] | 1814 | list_add_tail(&req->queuelist, &plug->list); |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 1815 | blk_account_io_start(req, true); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1816 | } else { |
| 1817 | spin_lock_irq(q->queue_lock); |
| 1818 | add_acct_request(q, req, where); |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 1819 | __blk_run_queue(q); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 1820 | out_unlock: |
| 1821 | spin_unlock_irq(q->queue_lock); |
| 1822 | } |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 1823 | |
| 1824 | return BLK_QC_T_NONE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1825 | } |
| 1826 | |
| 1827 | /* |
| 1828 | * If bio->bi_dev is a partition, remap the location |
| 1829 | */ |
| 1830 | static inline void blk_partition_remap(struct bio *bio) |
| 1831 | { |
| 1832 | struct block_device *bdev = bio->bi_bdev; |
| 1833 | |
Jens Axboe | bf2de6f | 2007-09-27 13:01:25 +0200 | [diff] [blame] | 1834 | if (bio_sectors(bio) && bdev != bdev->bd_contains) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1835 | struct hd_struct *p = bdev->bd_part; |
Jens Axboe | a362357 | 2005-11-01 09:26:16 +0100 | [diff] [blame] | 1836 | |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1837 | bio->bi_iter.bi_sector += p->start_sect; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1838 | bio->bi_bdev = bdev->bd_contains; |
Alan D. Brunelle | c7149d6 | 2007-08-07 15:30:23 +0200 | [diff] [blame] | 1839 | |
Mike Snitzer | d07335e | 2010-11-16 12:52:38 +0100 | [diff] [blame] | 1840 | trace_block_bio_remap(bdev_get_queue(bio->bi_bdev), bio, |
| 1841 | bdev->bd_dev, |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1842 | bio->bi_iter.bi_sector - p->start_sect); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1843 | } |
| 1844 | } |
| 1845 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1846 | static void handle_bad_sector(struct bio *bio) |
| 1847 | { |
| 1848 | char b[BDEVNAME_SIZE]; |
| 1849 | |
| 1850 | printk(KERN_INFO "attempt to access beyond end of device\n"); |
| 1851 | printk(KERN_INFO "%s: rw=%ld, want=%Lu, limit=%Lu\n", |
| 1852 | bdevname(bio->bi_bdev, b), |
| 1853 | bio->bi_rw, |
Kent Overstreet | f73a1c7 | 2012-09-25 15:05:12 -0700 | [diff] [blame] | 1854 | (unsigned long long)bio_end_sector(bio), |
Mike Snitzer | 77304d2 | 2010-11-08 14:39:12 +0100 | [diff] [blame] | 1855 | (long long)(i_size_read(bio->bi_bdev->bd_inode) >> 9)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1856 | } |
| 1857 | |
Akinobu Mita | c17bb49 | 2006-12-08 02:39:46 -0800 | [diff] [blame] | 1858 | #ifdef CONFIG_FAIL_MAKE_REQUEST |
| 1859 | |
| 1860 | static DECLARE_FAULT_ATTR(fail_make_request); |
| 1861 | |
| 1862 | static int __init setup_fail_make_request(char *str) |
| 1863 | { |
| 1864 | return setup_fault_attr(&fail_make_request, str); |
| 1865 | } |
| 1866 | __setup("fail_make_request=", setup_fail_make_request); |
| 1867 | |
Akinobu Mita | b2c9cd3 | 2011-07-26 16:09:03 -0700 | [diff] [blame] | 1868 | static bool should_fail_request(struct hd_struct *part, unsigned int bytes) |
Akinobu Mita | c17bb49 | 2006-12-08 02:39:46 -0800 | [diff] [blame] | 1869 | { |
Akinobu Mita | b2c9cd3 | 2011-07-26 16:09:03 -0700 | [diff] [blame] | 1870 | return part->make_it_fail && should_fail(&fail_make_request, bytes); |
Akinobu Mita | c17bb49 | 2006-12-08 02:39:46 -0800 | [diff] [blame] | 1871 | } |
| 1872 | |
| 1873 | static int __init fail_make_request_debugfs(void) |
| 1874 | { |
Akinobu Mita | dd48c08 | 2011-08-03 16:21:01 -0700 | [diff] [blame] | 1875 | struct dentry *dir = fault_create_debugfs_attr("fail_make_request", |
| 1876 | NULL, &fail_make_request); |
| 1877 | |
Duan Jiong | 21f9fcd | 2014-04-11 15:58:56 +0800 | [diff] [blame] | 1878 | return PTR_ERR_OR_ZERO(dir); |
Akinobu Mita | c17bb49 | 2006-12-08 02:39:46 -0800 | [diff] [blame] | 1879 | } |
| 1880 | |
| 1881 | late_initcall(fail_make_request_debugfs); |
| 1882 | |
| 1883 | #else /* CONFIG_FAIL_MAKE_REQUEST */ |
| 1884 | |
Akinobu Mita | b2c9cd3 | 2011-07-26 16:09:03 -0700 | [diff] [blame] | 1885 | static inline bool should_fail_request(struct hd_struct *part, |
| 1886 | unsigned int bytes) |
Akinobu Mita | c17bb49 | 2006-12-08 02:39:46 -0800 | [diff] [blame] | 1887 | { |
Akinobu Mita | b2c9cd3 | 2011-07-26 16:09:03 -0700 | [diff] [blame] | 1888 | return false; |
Akinobu Mita | c17bb49 | 2006-12-08 02:39:46 -0800 | [diff] [blame] | 1889 | } |
| 1890 | |
| 1891 | #endif /* CONFIG_FAIL_MAKE_REQUEST */ |
| 1892 | |
Jens Axboe | c07e2b4 | 2007-07-18 13:27:58 +0200 | [diff] [blame] | 1893 | /* |
| 1894 | * Check whether this bio extends beyond the end of the device. |
| 1895 | */ |
| 1896 | static inline int bio_check_eod(struct bio *bio, unsigned int nr_sectors) |
| 1897 | { |
| 1898 | sector_t maxsector; |
| 1899 | |
| 1900 | if (!nr_sectors) |
| 1901 | return 0; |
| 1902 | |
| 1903 | /* Test device or partition size, when known. */ |
Mike Snitzer | 77304d2 | 2010-11-08 14:39:12 +0100 | [diff] [blame] | 1904 | maxsector = i_size_read(bio->bi_bdev->bd_inode) >> 9; |
Jens Axboe | c07e2b4 | 2007-07-18 13:27:58 +0200 | [diff] [blame] | 1905 | if (maxsector) { |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1906 | sector_t sector = bio->bi_iter.bi_sector; |
Jens Axboe | c07e2b4 | 2007-07-18 13:27:58 +0200 | [diff] [blame] | 1907 | |
| 1908 | if (maxsector < nr_sectors || maxsector - nr_sectors < sector) { |
| 1909 | /* |
| 1910 | * This may well happen - the kernel calls bread() |
| 1911 | * without checking the size of the device, e.g., when |
| 1912 | * mounting a device. |
| 1913 | */ |
| 1914 | handle_bad_sector(bio); |
| 1915 | return 1; |
| 1916 | } |
| 1917 | } |
| 1918 | |
| 1919 | return 0; |
| 1920 | } |
| 1921 | |
Christoph Hellwig | 27a84d5 | 2011-09-15 14:01:40 +0200 | [diff] [blame] | 1922 | static noinline_for_stack bool |
| 1923 | generic_make_request_checks(struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1924 | { |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 1925 | struct request_queue *q; |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1926 | int nr_sectors = bio_sectors(bio); |
Jens Axboe | 51fd77b | 2007-11-02 08:49:08 +0100 | [diff] [blame] | 1927 | int err = -EIO; |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1928 | char b[BDEVNAME_SIZE]; |
| 1929 | struct hd_struct *part; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1930 | |
| 1931 | might_sleep(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1932 | |
Jens Axboe | c07e2b4 | 2007-07-18 13:27:58 +0200 | [diff] [blame] | 1933 | if (bio_check_eod(bio, nr_sectors)) |
| 1934 | goto end_io; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1935 | |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1936 | q = bdev_get_queue(bio->bi_bdev); |
| 1937 | if (unlikely(!q)) { |
| 1938 | printk(KERN_ERR |
| 1939 | "generic_make_request: Trying to access " |
| 1940 | "nonexistent block-device %s (%Lu)\n", |
| 1941 | bdevname(bio->bi_bdev, b), |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1942 | (long long) bio->bi_iter.bi_sector); |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1943 | goto end_io; |
| 1944 | } |
| 1945 | |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1946 | part = bio->bi_bdev->bd_part; |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1947 | if (should_fail_request(part, bio->bi_iter.bi_size) || |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1948 | should_fail_request(&part_to_disk(part)->part0, |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 1949 | bio->bi_iter.bi_size)) |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1950 | goto end_io; |
| 1951 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1952 | /* |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1953 | * If this device has partitions, remap block n |
| 1954 | * of partition p to block n+start(p) of the disk. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1955 | */ |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1956 | blk_partition_remap(bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1957 | |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1958 | if (bio_check_eod(bio, nr_sectors)) |
| 1959 | goto end_io; |
| 1960 | |
| 1961 | /* |
| 1962 | * Filter flush bio's early so that make_request based |
| 1963 | * drivers without flush support don't have to worry |
| 1964 | * about them. |
| 1965 | */ |
| 1966 | if ((bio->bi_rw & (REQ_FLUSH | REQ_FUA)) && !q->flush_flags) { |
| 1967 | bio->bi_rw &= ~(REQ_FLUSH | REQ_FUA); |
| 1968 | if (!nr_sectors) { |
| 1969 | err = 0; |
Tejun Heo | a738467 | 2008-11-28 13:32:03 +0900 | [diff] [blame] | 1970 | goto end_io; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1971 | } |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1972 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1973 | |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1974 | if ((bio->bi_rw & REQ_DISCARD) && |
| 1975 | (!blk_queue_discard(q) || |
Martin K. Petersen | e2a60da | 2012-09-18 12:19:25 -0400 | [diff] [blame] | 1976 | ((bio->bi_rw & REQ_SECURE) && !blk_queue_secdiscard(q)))) { |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1977 | err = -EOPNOTSUPP; |
| 1978 | goto end_io; |
| 1979 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1980 | |
Martin K. Petersen | 4363ac7 | 2012-09-18 12:19:27 -0400 | [diff] [blame] | 1981 | if (bio->bi_rw & REQ_WRITE_SAME && !bdev_write_same(bio->bi_bdev)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1982 | err = -EOPNOTSUPP; |
| 1983 | goto end_io; |
| 1984 | } |
| 1985 | |
Tejun Heo | 7f4b35d | 2012-06-04 20:40:56 -0700 | [diff] [blame] | 1986 | /* |
| 1987 | * Various block parts want %current->io_context and lazy ioc |
| 1988 | * allocation ends up trading a lot of pain for a small amount of |
| 1989 | * memory. Just allocate it upfront. This may fail and block |
| 1990 | * layer knows how to live with it. |
| 1991 | */ |
| 1992 | create_io_context(GFP_ATOMIC, q->node); |
| 1993 | |
Tejun Heo | ae11889 | 2015-08-18 14:55:20 -0700 | [diff] [blame] | 1994 | if (!blkcg_bio_issue_check(q, bio)) |
| 1995 | return false; |
Christoph Hellwig | 27a84d5 | 2011-09-15 14:01:40 +0200 | [diff] [blame] | 1996 | |
Christoph Hellwig | 5a7bbad | 2011-09-12 12:12:01 +0200 | [diff] [blame] | 1997 | trace_block_bio_queue(q, bio); |
Christoph Hellwig | 27a84d5 | 2011-09-15 14:01:40 +0200 | [diff] [blame] | 1998 | return true; |
Tejun Heo | a738467 | 2008-11-28 13:32:03 +0900 | [diff] [blame] | 1999 | |
| 2000 | end_io: |
Christoph Hellwig | 4246a0b | 2015-07-20 15:29:37 +0200 | [diff] [blame] | 2001 | bio->bi_error = err; |
| 2002 | bio_endio(bio); |
Christoph Hellwig | 27a84d5 | 2011-09-15 14:01:40 +0200 | [diff] [blame] | 2003 | return false; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2004 | } |
| 2005 | |
Christoph Hellwig | 27a84d5 | 2011-09-15 14:01:40 +0200 | [diff] [blame] | 2006 | /** |
| 2007 | * generic_make_request - hand a buffer to its device driver for I/O |
| 2008 | * @bio: The bio describing the location in memory and on the device. |
| 2009 | * |
| 2010 | * generic_make_request() is used to make I/O requests of block |
| 2011 | * devices. It is passed a &struct bio, which describes the I/O that needs |
| 2012 | * to be done. |
| 2013 | * |
| 2014 | * generic_make_request() does not return any status. The |
| 2015 | * success/failure status of the request, along with notification of |
| 2016 | * completion, is delivered asynchronously through the bio->bi_end_io |
| 2017 | * function described (one day) else where. |
| 2018 | * |
| 2019 | * The caller of generic_make_request must make sure that bi_io_vec |
| 2020 | * are set to describe the memory buffer, and that bi_dev and bi_sector are |
| 2021 | * set to describe the device address, and the |
| 2022 | * bi_end_io and optionally bi_private are set to describe how |
| 2023 | * completion notification should be signaled. |
| 2024 | * |
| 2025 | * generic_make_request and the drivers it calls may use bi_next if this |
| 2026 | * bio happens to be merged with someone else, and may resubmit the bio to |
| 2027 | * a lower device by calling into generic_make_request recursively, which |
| 2028 | * means the bio should NOT be touched after the call to ->make_request_fn. |
Neil Brown | d89d879 | 2007-05-01 09:53:42 +0200 | [diff] [blame] | 2029 | */ |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 2030 | blk_qc_t generic_make_request(struct bio *bio) |
Neil Brown | d89d879 | 2007-05-01 09:53:42 +0200 | [diff] [blame] | 2031 | { |
Akinobu Mita | bddd87c | 2010-02-23 08:55:42 +0100 | [diff] [blame] | 2032 | struct bio_list bio_list_on_stack; |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 2033 | blk_qc_t ret = BLK_QC_T_NONE; |
Akinobu Mita | bddd87c | 2010-02-23 08:55:42 +0100 | [diff] [blame] | 2034 | |
Christoph Hellwig | 27a84d5 | 2011-09-15 14:01:40 +0200 | [diff] [blame] | 2035 | if (!generic_make_request_checks(bio)) |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 2036 | goto out; |
Christoph Hellwig | 27a84d5 | 2011-09-15 14:01:40 +0200 | [diff] [blame] | 2037 | |
| 2038 | /* |
| 2039 | * We only want one ->make_request_fn to be active at a time, else |
| 2040 | * stack usage with stacked devices could be a problem. So use |
| 2041 | * current->bio_list to keep a list of requests submited by a |
| 2042 | * make_request_fn function. current->bio_list is also used as a |
| 2043 | * flag to say if generic_make_request is currently active in this |
| 2044 | * task or not. If it is NULL, then no make_request is active. If |
| 2045 | * it is non-NULL, then a make_request is active, and new requests |
| 2046 | * should be added at the tail |
| 2047 | */ |
Akinobu Mita | bddd87c | 2010-02-23 08:55:42 +0100 | [diff] [blame] | 2048 | if (current->bio_list) { |
Akinobu Mita | bddd87c | 2010-02-23 08:55:42 +0100 | [diff] [blame] | 2049 | bio_list_add(current->bio_list, bio); |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 2050 | goto out; |
Neil Brown | d89d879 | 2007-05-01 09:53:42 +0200 | [diff] [blame] | 2051 | } |
Christoph Hellwig | 27a84d5 | 2011-09-15 14:01:40 +0200 | [diff] [blame] | 2052 | |
Neil Brown | d89d879 | 2007-05-01 09:53:42 +0200 | [diff] [blame] | 2053 | /* following loop may be a bit non-obvious, and so deserves some |
| 2054 | * explanation. |
| 2055 | * Before entering the loop, bio->bi_next is NULL (as all callers |
| 2056 | * ensure that) so we have a list with a single bio. |
| 2057 | * We pretend that we have just taken it off a longer list, so |
Akinobu Mita | bddd87c | 2010-02-23 08:55:42 +0100 | [diff] [blame] | 2058 | * we assign bio_list to a pointer to the bio_list_on_stack, |
| 2059 | * thus initialising the bio_list of new bios to be |
Christoph Hellwig | 27a84d5 | 2011-09-15 14:01:40 +0200 | [diff] [blame] | 2060 | * added. ->make_request() may indeed add some more bios |
Neil Brown | d89d879 | 2007-05-01 09:53:42 +0200 | [diff] [blame] | 2061 | * through a recursive call to generic_make_request. If it |
| 2062 | * did, we find a non-NULL value in bio_list and re-enter the loop |
| 2063 | * from the top. In this case we really did just take the bio |
Akinobu Mita | bddd87c | 2010-02-23 08:55:42 +0100 | [diff] [blame] | 2064 | * of the top of the list (no pretending) and so remove it from |
Christoph Hellwig | 27a84d5 | 2011-09-15 14:01:40 +0200 | [diff] [blame] | 2065 | * bio_list, and call into ->make_request() again. |
Neil Brown | d89d879 | 2007-05-01 09:53:42 +0200 | [diff] [blame] | 2066 | */ |
| 2067 | BUG_ON(bio->bi_next); |
Akinobu Mita | bddd87c | 2010-02-23 08:55:42 +0100 | [diff] [blame] | 2068 | bio_list_init(&bio_list_on_stack); |
| 2069 | current->bio_list = &bio_list_on_stack; |
Neil Brown | d89d879 | 2007-05-01 09:53:42 +0200 | [diff] [blame] | 2070 | do { |
Christoph Hellwig | 27a84d5 | 2011-09-15 14:01:40 +0200 | [diff] [blame] | 2071 | struct request_queue *q = bdev_get_queue(bio->bi_bdev); |
| 2072 | |
Christoph Hellwig | 6f3b0e8 | 2015-11-26 09:13:05 +0100 | [diff] [blame] | 2073 | if (likely(blk_queue_enter(q, false) == 0)) { |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 2074 | ret = q->make_request_fn(q, bio); |
Dan Williams | 3ef28e8 | 2015-10-21 13:20:12 -0400 | [diff] [blame] | 2075 | |
| 2076 | blk_queue_exit(q); |
| 2077 | |
| 2078 | bio = bio_list_pop(current->bio_list); |
| 2079 | } else { |
| 2080 | struct bio *bio_next = bio_list_pop(current->bio_list); |
| 2081 | |
| 2082 | bio_io_error(bio); |
| 2083 | bio = bio_next; |
| 2084 | } |
Neil Brown | d89d879 | 2007-05-01 09:53:42 +0200 | [diff] [blame] | 2085 | } while (bio); |
Akinobu Mita | bddd87c | 2010-02-23 08:55:42 +0100 | [diff] [blame] | 2086 | current->bio_list = NULL; /* deactivate */ |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 2087 | |
| 2088 | out: |
| 2089 | return ret; |
Neil Brown | d89d879 | 2007-05-01 09:53:42 +0200 | [diff] [blame] | 2090 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2091 | EXPORT_SYMBOL(generic_make_request); |
| 2092 | |
| 2093 | /** |
Randy Dunlap | 710027a | 2008-08-19 20:13:11 +0200 | [diff] [blame] | 2094 | * submit_bio - submit a bio to the block device layer for I/O |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2095 | * @rw: whether to %READ or %WRITE, or maybe to %READA (read ahead) |
| 2096 | * @bio: The &struct bio which describes the I/O |
| 2097 | * |
| 2098 | * submit_bio() is very similar in purpose to generic_make_request(), and |
| 2099 | * uses that function to do most of the work. Both are fairly rough |
Randy Dunlap | 710027a | 2008-08-19 20:13:11 +0200 | [diff] [blame] | 2100 | * interfaces; @bio must be presetup and ready for I/O. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2101 | * |
| 2102 | */ |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 2103 | blk_qc_t submit_bio(int rw, struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2104 | { |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 2105 | bio->bi_rw |= rw; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2106 | |
Jens Axboe | bf2de6f | 2007-09-27 13:01:25 +0200 | [diff] [blame] | 2107 | /* |
| 2108 | * If it's a regular read/write or a barrier with data attached, |
| 2109 | * go through the normal accounting stuff before submission. |
| 2110 | */ |
Martin K. Petersen | e2a60da | 2012-09-18 12:19:25 -0400 | [diff] [blame] | 2111 | if (bio_has_data(bio)) { |
Martin K. Petersen | 4363ac7 | 2012-09-18 12:19:27 -0400 | [diff] [blame] | 2112 | unsigned int count; |
| 2113 | |
| 2114 | if (unlikely(rw & REQ_WRITE_SAME)) |
| 2115 | count = bdev_logical_block_size(bio->bi_bdev) >> 9; |
| 2116 | else |
| 2117 | count = bio_sectors(bio); |
| 2118 | |
Jens Axboe | bf2de6f | 2007-09-27 13:01:25 +0200 | [diff] [blame] | 2119 | if (rw & WRITE) { |
| 2120 | count_vm_events(PGPGOUT, count); |
| 2121 | } else { |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 2122 | task_io_account_read(bio->bi_iter.bi_size); |
Jens Axboe | bf2de6f | 2007-09-27 13:01:25 +0200 | [diff] [blame] | 2123 | count_vm_events(PGPGIN, count); |
| 2124 | } |
| 2125 | |
| 2126 | if (unlikely(block_dump)) { |
| 2127 | char b[BDEVNAME_SIZE]; |
San Mehat | 8dcbdc7 | 2010-09-14 08:48:01 +0200 | [diff] [blame] | 2128 | printk(KERN_DEBUG "%s(%d): %s block %Lu on %s (%u sectors)\n", |
Pavel Emelyanov | ba25f9d | 2007-10-18 23:40:40 -0700 | [diff] [blame] | 2129 | current->comm, task_pid_nr(current), |
Jens Axboe | bf2de6f | 2007-09-27 13:01:25 +0200 | [diff] [blame] | 2130 | (rw & WRITE) ? "WRITE" : "READ", |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 2131 | (unsigned long long)bio->bi_iter.bi_sector, |
San Mehat | 8dcbdc7 | 2010-09-14 08:48:01 +0200 | [diff] [blame] | 2132 | bdevname(bio->bi_bdev, b), |
| 2133 | count); |
Jens Axboe | bf2de6f | 2007-09-27 13:01:25 +0200 | [diff] [blame] | 2134 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2135 | } |
| 2136 | |
Jens Axboe | dece163 | 2015-11-05 10:41:16 -0700 | [diff] [blame] | 2137 | return generic_make_request(bio); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2138 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2139 | EXPORT_SYMBOL(submit_bio); |
| 2140 | |
Kiyoshi Ueda | 3bcddea | 2007-12-11 17:52:28 -0500 | [diff] [blame] | 2141 | /** |
Hannes Reinecke | bf4e6b4 | 2015-11-26 08:46:57 +0100 | [diff] [blame] | 2142 | * blk_cloned_rq_check_limits - Helper function to check a cloned request |
| 2143 | * for new the queue limits |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2144 | * @q: the queue |
| 2145 | * @rq: the request being checked |
| 2146 | * |
| 2147 | * Description: |
| 2148 | * @rq may have been made based on weaker limitations of upper-level queues |
| 2149 | * in request stacking drivers, and it may violate the limitation of @q. |
| 2150 | * Since the block layer and the underlying device driver trust @rq |
| 2151 | * after it is inserted to @q, it should be checked against @q before |
| 2152 | * the insertion using this generic function. |
| 2153 | * |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2154 | * Request stacking drivers like request-based dm may change the queue |
Hannes Reinecke | bf4e6b4 | 2015-11-26 08:46:57 +0100 | [diff] [blame] | 2155 | * limits when retrying requests on other queues. Those requests need |
| 2156 | * to be checked against the new queue limits again during dispatch. |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2157 | */ |
Hannes Reinecke | bf4e6b4 | 2015-11-26 08:46:57 +0100 | [diff] [blame] | 2158 | static int blk_cloned_rq_check_limits(struct request_queue *q, |
| 2159 | struct request *rq) |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2160 | { |
Martin K. Petersen | f31dc1c | 2012-09-18 12:19:26 -0400 | [diff] [blame] | 2161 | if (blk_rq_sectors(rq) > blk_queue_get_max_sectors(q, rq->cmd_flags)) { |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2162 | printk(KERN_ERR "%s: over max size limit.\n", __func__); |
| 2163 | return -EIO; |
| 2164 | } |
| 2165 | |
| 2166 | /* |
| 2167 | * queue's settings related to segment counting like q->bounce_pfn |
| 2168 | * may differ from that of other stacking queues. |
| 2169 | * Recalculate it to check the request correctly on this queue's |
| 2170 | * limitation. |
| 2171 | */ |
| 2172 | blk_recalc_rq_segments(rq); |
Martin K. Petersen | 8a78362 | 2010-02-26 00:20:39 -0500 | [diff] [blame] | 2173 | if (rq->nr_phys_segments > queue_max_segments(q)) { |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2174 | printk(KERN_ERR "%s: over max segments limit.\n", __func__); |
| 2175 | return -EIO; |
| 2176 | } |
| 2177 | |
| 2178 | return 0; |
| 2179 | } |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2180 | |
| 2181 | /** |
| 2182 | * blk_insert_cloned_request - Helper for stacking drivers to submit a request |
| 2183 | * @q: the queue to submit the request |
| 2184 | * @rq: the request being queued |
| 2185 | */ |
| 2186 | int blk_insert_cloned_request(struct request_queue *q, struct request *rq) |
| 2187 | { |
| 2188 | unsigned long flags; |
Jeff Moyer | 4853aba | 2011-08-15 21:37:25 +0200 | [diff] [blame] | 2189 | int where = ELEVATOR_INSERT_BACK; |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2190 | |
Hannes Reinecke | bf4e6b4 | 2015-11-26 08:46:57 +0100 | [diff] [blame] | 2191 | if (blk_cloned_rq_check_limits(q, rq)) |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2192 | return -EIO; |
| 2193 | |
Akinobu Mita | b2c9cd3 | 2011-07-26 16:09:03 -0700 | [diff] [blame] | 2194 | if (rq->rq_disk && |
| 2195 | should_fail_request(&rq->rq_disk->part0, blk_rq_bytes(rq))) |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2196 | return -EIO; |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2197 | |
Keith Busch | 7fb4898 | 2014-10-17 17:46:38 -0600 | [diff] [blame] | 2198 | if (q->mq_ops) { |
| 2199 | if (blk_queue_io_stat(q)) |
| 2200 | blk_account_io_start(rq, true); |
| 2201 | blk_mq_insert_request(rq, false, true, true); |
| 2202 | return 0; |
| 2203 | } |
| 2204 | |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2205 | spin_lock_irqsave(q->queue_lock, flags); |
Bart Van Assche | 3f3299d | 2012-11-28 13:42:38 +0100 | [diff] [blame] | 2206 | if (unlikely(blk_queue_dying(q))) { |
Tejun Heo | 8ba6143 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 2207 | spin_unlock_irqrestore(q->queue_lock, flags); |
| 2208 | return -ENODEV; |
| 2209 | } |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2210 | |
| 2211 | /* |
| 2212 | * Submitting request must be dequeued before calling this function |
| 2213 | * because it will be linked to another request_queue |
| 2214 | */ |
| 2215 | BUG_ON(blk_queued_rq(rq)); |
| 2216 | |
Jeff Moyer | 4853aba | 2011-08-15 21:37:25 +0200 | [diff] [blame] | 2217 | if (rq->cmd_flags & (REQ_FLUSH|REQ_FUA)) |
| 2218 | where = ELEVATOR_INSERT_FLUSH; |
| 2219 | |
| 2220 | add_acct_request(q, rq, where); |
Jeff Moyer | e67b77c | 2011-10-17 12:57:23 +0200 | [diff] [blame] | 2221 | if (where == ELEVATOR_INSERT_FLUSH) |
| 2222 | __blk_run_queue(q); |
Kiyoshi Ueda | 82124d6 | 2008-09-18 10:45:38 -0400 | [diff] [blame] | 2223 | spin_unlock_irqrestore(q->queue_lock, flags); |
| 2224 | |
| 2225 | return 0; |
| 2226 | } |
| 2227 | EXPORT_SYMBOL_GPL(blk_insert_cloned_request); |
| 2228 | |
Tejun Heo | 80a761f | 2009-07-03 17:48:17 +0900 | [diff] [blame] | 2229 | /** |
| 2230 | * blk_rq_err_bytes - determine number of bytes till the next failure boundary |
| 2231 | * @rq: request to examine |
| 2232 | * |
| 2233 | * Description: |
| 2234 | * A request could be merge of IOs which require different failure |
| 2235 | * handling. This function determines the number of bytes which |
| 2236 | * can be failed from the beginning of the request without |
| 2237 | * crossing into area which need to be retried further. |
| 2238 | * |
| 2239 | * Return: |
| 2240 | * The number of bytes to fail. |
| 2241 | * |
| 2242 | * Context: |
| 2243 | * queue_lock must be held. |
| 2244 | */ |
| 2245 | unsigned int blk_rq_err_bytes(const struct request *rq) |
| 2246 | { |
| 2247 | unsigned int ff = rq->cmd_flags & REQ_FAILFAST_MASK; |
| 2248 | unsigned int bytes = 0; |
| 2249 | struct bio *bio; |
| 2250 | |
| 2251 | if (!(rq->cmd_flags & REQ_MIXED_MERGE)) |
| 2252 | return blk_rq_bytes(rq); |
| 2253 | |
| 2254 | /* |
| 2255 | * Currently the only 'mixing' which can happen is between |
| 2256 | * different fastfail types. We can safely fail portions |
| 2257 | * which have all the failfast bits that the first one has - |
| 2258 | * the ones which are at least as eager to fail as the first |
| 2259 | * one. |
| 2260 | */ |
| 2261 | for (bio = rq->bio; bio; bio = bio->bi_next) { |
| 2262 | if ((bio->bi_rw & ff) != ff) |
| 2263 | break; |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 2264 | bytes += bio->bi_iter.bi_size; |
Tejun Heo | 80a761f | 2009-07-03 17:48:17 +0900 | [diff] [blame] | 2265 | } |
| 2266 | |
| 2267 | /* this could lead to infinite loop */ |
| 2268 | BUG_ON(blk_rq_bytes(rq) && !bytes); |
| 2269 | return bytes; |
| 2270 | } |
| 2271 | EXPORT_SYMBOL_GPL(blk_rq_err_bytes); |
| 2272 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 2273 | void blk_account_io_completion(struct request *req, unsigned int bytes) |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2274 | { |
Jens Axboe | c2553b5 | 2009-04-24 08:10:11 +0200 | [diff] [blame] | 2275 | if (blk_do_io_stat(req)) { |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2276 | const int rw = rq_data_dir(req); |
| 2277 | struct hd_struct *part; |
| 2278 | int cpu; |
| 2279 | |
| 2280 | cpu = part_stat_lock(); |
Jerome Marchand | 09e099d | 2011-01-05 16:57:38 +0100 | [diff] [blame] | 2281 | part = req->part; |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2282 | part_stat_add(cpu, part, sectors[rw], bytes >> 9); |
| 2283 | part_stat_unlock(); |
| 2284 | } |
| 2285 | } |
| 2286 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 2287 | void blk_account_io_done(struct request *req) |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2288 | { |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2289 | /* |
Tejun Heo | dd4c133 | 2010-09-03 11:56:16 +0200 | [diff] [blame] | 2290 | * Account IO completion. flush_rq isn't accounted as a |
| 2291 | * normal IO on queueing nor completion. Accounting the |
| 2292 | * containing request is enough. |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2293 | */ |
Tejun Heo | 414b4ff | 2011-01-25 12:43:49 +0100 | [diff] [blame] | 2294 | if (blk_do_io_stat(req) && !(req->cmd_flags & REQ_FLUSH_SEQ)) { |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2295 | unsigned long duration = jiffies - req->start_time; |
| 2296 | const int rw = rq_data_dir(req); |
| 2297 | struct hd_struct *part; |
| 2298 | int cpu; |
| 2299 | |
| 2300 | cpu = part_stat_lock(); |
Jerome Marchand | 09e099d | 2011-01-05 16:57:38 +0100 | [diff] [blame] | 2301 | part = req->part; |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2302 | |
| 2303 | part_stat_inc(cpu, part, ios[rw]); |
| 2304 | part_stat_add(cpu, part, ticks[rw], duration); |
| 2305 | part_round_stats(cpu, part); |
Nikanth Karthikesan | 316d315 | 2009-10-06 20:16:55 +0200 | [diff] [blame] | 2306 | part_dec_in_flight(part, rw); |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2307 | |
Jens Axboe | 6c23a96 | 2011-01-07 08:43:37 +0100 | [diff] [blame] | 2308 | hd_struct_put(part); |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2309 | part_stat_unlock(); |
| 2310 | } |
| 2311 | } |
| 2312 | |
Rafael J. Wysocki | 47fafbc | 2014-12-04 01:00:23 +0100 | [diff] [blame] | 2313 | #ifdef CONFIG_PM |
Lin Ming | c815881 | 2013-03-23 11:42:27 +0800 | [diff] [blame] | 2314 | /* |
| 2315 | * Don't process normal requests when queue is suspended |
| 2316 | * or in the process of suspending/resuming |
| 2317 | */ |
| 2318 | static struct request *blk_pm_peek_request(struct request_queue *q, |
| 2319 | struct request *rq) |
| 2320 | { |
| 2321 | if (q->dev && (q->rpm_status == RPM_SUSPENDED || |
| 2322 | (q->rpm_status != RPM_ACTIVE && !(rq->cmd_flags & REQ_PM)))) |
| 2323 | return NULL; |
| 2324 | else |
| 2325 | return rq; |
| 2326 | } |
| 2327 | #else |
| 2328 | static inline struct request *blk_pm_peek_request(struct request_queue *q, |
| 2329 | struct request *rq) |
| 2330 | { |
| 2331 | return rq; |
| 2332 | } |
| 2333 | #endif |
| 2334 | |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 2335 | void blk_account_io_start(struct request *rq, bool new_io) |
| 2336 | { |
| 2337 | struct hd_struct *part; |
| 2338 | int rw = rq_data_dir(rq); |
| 2339 | int cpu; |
| 2340 | |
| 2341 | if (!blk_do_io_stat(rq)) |
| 2342 | return; |
| 2343 | |
| 2344 | cpu = part_stat_lock(); |
| 2345 | |
| 2346 | if (!new_io) { |
| 2347 | part = rq->part; |
| 2348 | part_stat_inc(cpu, part, merges[rw]); |
| 2349 | } else { |
| 2350 | part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq)); |
| 2351 | if (!hd_struct_try_get(part)) { |
| 2352 | /* |
| 2353 | * The partition is already being removed, |
| 2354 | * the request will be accounted on the disk only |
| 2355 | * |
| 2356 | * We take a reference on disk->part0 although that |
| 2357 | * partition will never be deleted, so we can treat |
| 2358 | * it as any other partition. |
| 2359 | */ |
| 2360 | part = &rq->rq_disk->part0; |
| 2361 | hd_struct_get(part); |
| 2362 | } |
| 2363 | part_round_stats(cpu, part); |
| 2364 | part_inc_in_flight(part, rw); |
| 2365 | rq->part = part; |
| 2366 | } |
| 2367 | |
| 2368 | part_stat_unlock(); |
| 2369 | } |
| 2370 | |
Tejun Heo | 53a0880 | 2008-12-03 12:41:26 +0100 | [diff] [blame] | 2371 | /** |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 2372 | * blk_peek_request - peek at the top of a request queue |
| 2373 | * @q: request queue to peek at |
Kiyoshi Ueda | 3bcddea | 2007-12-11 17:52:28 -0500 | [diff] [blame] | 2374 | * |
| 2375 | * Description: |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 2376 | * Return the request at the top of @q. The returned request |
| 2377 | * should be started using blk_start_request() before LLD starts |
| 2378 | * processing it. |
Kiyoshi Ueda | 3bcddea | 2007-12-11 17:52:28 -0500 | [diff] [blame] | 2379 | * |
| 2380 | * Return: |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 2381 | * Pointer to the request at the top of @q if available. Null |
| 2382 | * otherwise. |
| 2383 | * |
| 2384 | * Context: |
| 2385 | * queue_lock must be held. |
| 2386 | */ |
| 2387 | struct request *blk_peek_request(struct request_queue *q) |
Tejun Heo | 158dbda | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2388 | { |
| 2389 | struct request *rq; |
| 2390 | int ret; |
| 2391 | |
| 2392 | while ((rq = __elv_next_request(q)) != NULL) { |
Lin Ming | c815881 | 2013-03-23 11:42:27 +0800 | [diff] [blame] | 2393 | |
| 2394 | rq = blk_pm_peek_request(q, rq); |
| 2395 | if (!rq) |
| 2396 | break; |
| 2397 | |
Tejun Heo | 158dbda | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2398 | if (!(rq->cmd_flags & REQ_STARTED)) { |
| 2399 | /* |
| 2400 | * This is the first time the device driver |
| 2401 | * sees this request (possibly after |
| 2402 | * requeueing). Notify IO scheduler. |
| 2403 | */ |
Christoph Hellwig | 33659eb | 2010-08-07 18:17:56 +0200 | [diff] [blame] | 2404 | if (rq->cmd_flags & REQ_SORTED) |
Tejun Heo | 158dbda | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2405 | elv_activate_rq(q, rq); |
| 2406 | |
| 2407 | /* |
| 2408 | * just mark as started even if we don't start |
| 2409 | * it, a request that has been delayed should |
| 2410 | * not be passed by new incoming requests |
| 2411 | */ |
| 2412 | rq->cmd_flags |= REQ_STARTED; |
| 2413 | trace_block_rq_issue(q, rq); |
| 2414 | } |
| 2415 | |
| 2416 | if (!q->boundary_rq || q->boundary_rq == rq) { |
| 2417 | q->end_sector = rq_end_sector(rq); |
| 2418 | q->boundary_rq = NULL; |
| 2419 | } |
| 2420 | |
| 2421 | if (rq->cmd_flags & REQ_DONTPREP) |
| 2422 | break; |
| 2423 | |
Tejun Heo | 2e46e8b | 2009-05-07 22:24:41 +0900 | [diff] [blame] | 2424 | if (q->dma_drain_size && blk_rq_bytes(rq)) { |
Tejun Heo | 158dbda | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2425 | /* |
| 2426 | * make sure space for the drain appears we |
| 2427 | * know we can do this because max_hw_segments |
| 2428 | * has been adjusted to be one fewer than the |
| 2429 | * device can handle |
| 2430 | */ |
| 2431 | rq->nr_phys_segments++; |
| 2432 | } |
| 2433 | |
| 2434 | if (!q->prep_rq_fn) |
| 2435 | break; |
| 2436 | |
| 2437 | ret = q->prep_rq_fn(q, rq); |
| 2438 | if (ret == BLKPREP_OK) { |
| 2439 | break; |
| 2440 | } else if (ret == BLKPREP_DEFER) { |
| 2441 | /* |
| 2442 | * the request may have been (partially) prepped. |
| 2443 | * we need to keep this request in the front to |
| 2444 | * avoid resource deadlock. REQ_STARTED will |
| 2445 | * prevent other fs requests from passing this one. |
| 2446 | */ |
Tejun Heo | 2e46e8b | 2009-05-07 22:24:41 +0900 | [diff] [blame] | 2447 | if (q->dma_drain_size && blk_rq_bytes(rq) && |
Tejun Heo | 158dbda | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2448 | !(rq->cmd_flags & REQ_DONTPREP)) { |
| 2449 | /* |
| 2450 | * remove the space for the drain we added |
| 2451 | * so that we don't add it again |
| 2452 | */ |
| 2453 | --rq->nr_phys_segments; |
| 2454 | } |
| 2455 | |
| 2456 | rq = NULL; |
| 2457 | break; |
Martin K. Petersen | 0fb5b1f | 2016-02-04 00:52:12 -0500 | [diff] [blame] | 2458 | } else if (ret == BLKPREP_KILL || ret == BLKPREP_INVALID) { |
| 2459 | int err = (ret == BLKPREP_INVALID) ? -EREMOTEIO : -EIO; |
| 2460 | |
Tejun Heo | 158dbda | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2461 | rq->cmd_flags |= REQ_QUIET; |
James Bottomley | c143dc9 | 2009-05-30 06:43:49 +0200 | [diff] [blame] | 2462 | /* |
| 2463 | * Mark this request as started so we don't trigger |
| 2464 | * any debug logic in the end I/O path. |
| 2465 | */ |
| 2466 | blk_start_request(rq); |
Martin K. Petersen | 0fb5b1f | 2016-02-04 00:52:12 -0500 | [diff] [blame] | 2467 | __blk_end_request_all(rq, err); |
Tejun Heo | 158dbda | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2468 | } else { |
| 2469 | printk(KERN_ERR "%s: bad return=%d\n", __func__, ret); |
| 2470 | break; |
| 2471 | } |
| 2472 | } |
| 2473 | |
| 2474 | return rq; |
| 2475 | } |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 2476 | EXPORT_SYMBOL(blk_peek_request); |
Tejun Heo | 158dbda | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2477 | |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 2478 | void blk_dequeue_request(struct request *rq) |
Tejun Heo | 158dbda | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2479 | { |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 2480 | struct request_queue *q = rq->q; |
| 2481 | |
Tejun Heo | 158dbda | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2482 | BUG_ON(list_empty(&rq->queuelist)); |
| 2483 | BUG_ON(ELV_ON_HASH(rq)); |
| 2484 | |
| 2485 | list_del_init(&rq->queuelist); |
| 2486 | |
| 2487 | /* |
| 2488 | * the time frame between a request being removed from the lists |
| 2489 | * and to it is freed is accounted as io that is in progress at |
| 2490 | * the driver side. |
| 2491 | */ |
Divyesh Shah | 9195291 | 2010-04-01 15:01:41 -0700 | [diff] [blame] | 2492 | if (blk_account_rq(rq)) { |
Jens Axboe | 0a7ae2f | 2009-05-20 08:54:31 +0200 | [diff] [blame] | 2493 | q->in_flight[rq_is_sync(rq)]++; |
Divyesh Shah | 9195291 | 2010-04-01 15:01:41 -0700 | [diff] [blame] | 2494 | set_io_start_time_ns(rq); |
| 2495 | } |
Tejun Heo | 158dbda | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2496 | } |
| 2497 | |
Tejun Heo | 5efccd1 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2498 | /** |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 2499 | * blk_start_request - start request processing on the driver |
| 2500 | * @req: request to dequeue |
| 2501 | * |
| 2502 | * Description: |
| 2503 | * Dequeue @req and start timeout timer on it. This hands off the |
| 2504 | * request to the driver. |
| 2505 | * |
| 2506 | * Block internal functions which don't want to start timer should |
| 2507 | * call blk_dequeue_request(). |
| 2508 | * |
| 2509 | * Context: |
| 2510 | * queue_lock must be held. |
| 2511 | */ |
| 2512 | void blk_start_request(struct request *req) |
| 2513 | { |
| 2514 | blk_dequeue_request(req); |
| 2515 | |
| 2516 | /* |
Tejun Heo | 5f49f63 | 2009-05-19 18:33:05 +0900 | [diff] [blame] | 2517 | * We are now handing the request to the hardware, initialize |
| 2518 | * resid_len to full count and add the timeout handler. |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 2519 | */ |
Tejun Heo | 5f49f63 | 2009-05-19 18:33:05 +0900 | [diff] [blame] | 2520 | req->resid_len = blk_rq_bytes(req); |
FUJITA Tomonori | dbb66c4 | 2009-06-09 05:47:10 +0200 | [diff] [blame] | 2521 | if (unlikely(blk_bidi_rq(req))) |
| 2522 | req->next_rq->resid_len = blk_rq_bytes(req->next_rq); |
| 2523 | |
Jeff Moyer | 4912aa6 | 2013-10-08 14:36:41 -0400 | [diff] [blame] | 2524 | BUG_ON(test_bit(REQ_ATOM_COMPLETE, &req->atomic_flags)); |
Tejun Heo | 9934c8c | 2009-05-08 11:54:16 +0900 | [diff] [blame] | 2525 | blk_add_timer(req); |
| 2526 | } |
| 2527 | EXPORT_SYMBOL(blk_start_request); |
| 2528 | |
| 2529 | /** |
| 2530 | * blk_fetch_request - fetch a request from a request queue |
| 2531 | * @q: request queue to fetch a request from |
| 2532 | * |
| 2533 | * Description: |
| 2534 | * Return the request at the top of @q. The request is started on |
| 2535 | * return and LLD can start processing it immediately. |
| 2536 | * |
| 2537 | * Return: |
| 2538 | * Pointer to the request at the top of @q if available. Null |
| 2539 | * otherwise. |
| 2540 | * |
| 2541 | * Context: |
| 2542 | * queue_lock must be held. |
| 2543 | */ |
| 2544 | struct request *blk_fetch_request(struct request_queue *q) |
| 2545 | { |
| 2546 | struct request *rq; |
| 2547 | |
| 2548 | rq = blk_peek_request(q); |
| 2549 | if (rq) |
| 2550 | blk_start_request(rq); |
| 2551 | return rq; |
| 2552 | } |
| 2553 | EXPORT_SYMBOL(blk_fetch_request); |
| 2554 | |
| 2555 | /** |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2556 | * blk_update_request - Special helper function for request stacking drivers |
Randy Dunlap | 8ebf975 | 2009-06-11 20:00:41 -0700 | [diff] [blame] | 2557 | * @req: the request being processed |
Kiyoshi Ueda | 3bcddea | 2007-12-11 17:52:28 -0500 | [diff] [blame] | 2558 | * @error: %0 for success, < %0 for error |
Randy Dunlap | 8ebf975 | 2009-06-11 20:00:41 -0700 | [diff] [blame] | 2559 | * @nr_bytes: number of bytes to complete @req |
Kiyoshi Ueda | 3bcddea | 2007-12-11 17:52:28 -0500 | [diff] [blame] | 2560 | * |
| 2561 | * Description: |
Randy Dunlap | 8ebf975 | 2009-06-11 20:00:41 -0700 | [diff] [blame] | 2562 | * Ends I/O on a number of bytes attached to @req, but doesn't complete |
| 2563 | * the request structure even if @req doesn't have leftover. |
| 2564 | * If @req has leftover, sets it up for the next range of segments. |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2565 | * |
| 2566 | * This special helper function is only for request stacking drivers |
| 2567 | * (e.g. request-based dm) so that they can handle partial completion. |
| 2568 | * Actual device drivers should use blk_end_request instead. |
| 2569 | * |
| 2570 | * Passing the result of blk_rq_bytes() as @nr_bytes guarantees |
| 2571 | * %false return from this function. |
Kiyoshi Ueda | 3bcddea | 2007-12-11 17:52:28 -0500 | [diff] [blame] | 2572 | * |
| 2573 | * Return: |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2574 | * %false - this request doesn't have any more data |
| 2575 | * %true - this request has more data |
Kiyoshi Ueda | 3bcddea | 2007-12-11 17:52:28 -0500 | [diff] [blame] | 2576 | **/ |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2577 | bool blk_update_request(struct request *req, int error, unsigned int nr_bytes) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2578 | { |
Kent Overstreet | f79ea41 | 2012-09-20 16:38:30 -0700 | [diff] [blame] | 2579 | int total_bytes; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2580 | |
Hannes Reinecke | 4a0efdc | 2014-10-01 14:32:31 +0200 | [diff] [blame] | 2581 | trace_block_rq_complete(req->q, req, nr_bytes); |
| 2582 | |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2583 | if (!req->bio) |
| 2584 | return false; |
| 2585 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2586 | /* |
Tejun Heo | 6f41469 | 2009-04-19 07:00:41 +0900 | [diff] [blame] | 2587 | * For fs requests, rq is just carrier of independent bio's |
| 2588 | * and each partial completion should be handled separately. |
| 2589 | * Reset per-request error on each partial completion. |
| 2590 | * |
| 2591 | * TODO: tj: This is too subtle. It would be better to let |
| 2592 | * low level drivers do what they see fit. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2593 | */ |
Christoph Hellwig | 33659eb | 2010-08-07 18:17:56 +0200 | [diff] [blame] | 2594 | if (req->cmd_type == REQ_TYPE_FS) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2595 | req->errors = 0; |
| 2596 | |
Christoph Hellwig | 33659eb | 2010-08-07 18:17:56 +0200 | [diff] [blame] | 2597 | if (error && req->cmd_type == REQ_TYPE_FS && |
| 2598 | !(req->cmd_flags & REQ_QUIET)) { |
Hannes Reinecke | 7977556 | 2011-01-18 10:13:13 +0100 | [diff] [blame] | 2599 | char *error_type; |
| 2600 | |
| 2601 | switch (error) { |
| 2602 | case -ENOLINK: |
| 2603 | error_type = "recoverable transport"; |
| 2604 | break; |
| 2605 | case -EREMOTEIO: |
| 2606 | error_type = "critical target"; |
| 2607 | break; |
| 2608 | case -EBADE: |
| 2609 | error_type = "critical nexus"; |
| 2610 | break; |
Hannes Reinecke | d1ffc1f | 2013-01-30 09:26:16 +0000 | [diff] [blame] | 2611 | case -ETIMEDOUT: |
| 2612 | error_type = "timeout"; |
| 2613 | break; |
Hannes Reinecke | a9d6ceb8 | 2013-07-01 15:16:25 +0200 | [diff] [blame] | 2614 | case -ENOSPC: |
| 2615 | error_type = "critical space allocation"; |
| 2616 | break; |
Hannes Reinecke | 7e782af | 2013-07-01 15:16:26 +0200 | [diff] [blame] | 2617 | case -ENODATA: |
| 2618 | error_type = "critical medium"; |
| 2619 | break; |
Hannes Reinecke | 7977556 | 2011-01-18 10:13:13 +0100 | [diff] [blame] | 2620 | case -EIO: |
| 2621 | default: |
| 2622 | error_type = "I/O"; |
| 2623 | break; |
| 2624 | } |
Robert Elliott | ef3ecb6 | 2014-08-27 10:50:31 -0500 | [diff] [blame] | 2625 | printk_ratelimited(KERN_ERR "%s: %s error, dev %s, sector %llu\n", |
| 2626 | __func__, error_type, req->rq_disk ? |
Yi Zou | 37d7b34 | 2012-08-30 16:26:25 -0700 | [diff] [blame] | 2627 | req->rq_disk->disk_name : "?", |
| 2628 | (unsigned long long)blk_rq_pos(req)); |
| 2629 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2630 | } |
| 2631 | |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2632 | blk_account_io_completion(req, nr_bytes); |
Jens Axboe | d72d904 | 2005-11-01 08:35:42 +0100 | [diff] [blame] | 2633 | |
Kent Overstreet | f79ea41 | 2012-09-20 16:38:30 -0700 | [diff] [blame] | 2634 | total_bytes = 0; |
| 2635 | while (req->bio) { |
| 2636 | struct bio *bio = req->bio; |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 2637 | unsigned bio_bytes = min(bio->bi_iter.bi_size, nr_bytes); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2638 | |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 2639 | if (bio_bytes == bio->bi_iter.bi_size) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2640 | req->bio = bio->bi_next; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2641 | |
Kent Overstreet | f79ea41 | 2012-09-20 16:38:30 -0700 | [diff] [blame] | 2642 | req_bio_endio(req, bio, bio_bytes, error); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2643 | |
Kent Overstreet | f79ea41 | 2012-09-20 16:38:30 -0700 | [diff] [blame] | 2644 | total_bytes += bio_bytes; |
| 2645 | nr_bytes -= bio_bytes; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2646 | |
Kent Overstreet | f79ea41 | 2012-09-20 16:38:30 -0700 | [diff] [blame] | 2647 | if (!nr_bytes) |
| 2648 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2649 | } |
| 2650 | |
| 2651 | /* |
| 2652 | * completely done |
| 2653 | */ |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2654 | if (!req->bio) { |
| 2655 | /* |
| 2656 | * Reset counters so that the request stacking driver |
| 2657 | * can find how many bytes remain in the request |
| 2658 | * later. |
| 2659 | */ |
Tejun Heo | a2dec7b | 2009-05-07 22:24:44 +0900 | [diff] [blame] | 2660 | req->__data_len = 0; |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2661 | return false; |
| 2662 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2663 | |
Tejun Heo | a2dec7b | 2009-05-07 22:24:44 +0900 | [diff] [blame] | 2664 | req->__data_len -= total_bytes; |
Tejun Heo | 2e46e8b | 2009-05-07 22:24:41 +0900 | [diff] [blame] | 2665 | |
| 2666 | /* update sector only for requests with clear definition of sector */ |
Martin K. Petersen | e2a60da | 2012-09-18 12:19:25 -0400 | [diff] [blame] | 2667 | if (req->cmd_type == REQ_TYPE_FS) |
Tejun Heo | a2dec7b | 2009-05-07 22:24:44 +0900 | [diff] [blame] | 2668 | req->__sector += total_bytes >> 9; |
Tejun Heo | 2e46e8b | 2009-05-07 22:24:41 +0900 | [diff] [blame] | 2669 | |
Tejun Heo | 80a761f | 2009-07-03 17:48:17 +0900 | [diff] [blame] | 2670 | /* mixed attributes always follow the first bio */ |
| 2671 | if (req->cmd_flags & REQ_MIXED_MERGE) { |
| 2672 | req->cmd_flags &= ~REQ_FAILFAST_MASK; |
| 2673 | req->cmd_flags |= req->bio->bi_rw & REQ_FAILFAST_MASK; |
| 2674 | } |
| 2675 | |
Tejun Heo | 2e46e8b | 2009-05-07 22:24:41 +0900 | [diff] [blame] | 2676 | /* |
| 2677 | * If total number of sectors is less than the first segment |
| 2678 | * size, something has gone terribly wrong. |
| 2679 | */ |
| 2680 | if (blk_rq_bytes(req) < blk_rq_cur_bytes(req)) { |
Jens Axboe | 8182924 | 2011-03-30 09:51:33 +0200 | [diff] [blame] | 2681 | blk_dump_rq_flags(req, "request botched"); |
Tejun Heo | a2dec7b | 2009-05-07 22:24:44 +0900 | [diff] [blame] | 2682 | req->__data_len = blk_rq_cur_bytes(req); |
Tejun Heo | 2e46e8b | 2009-05-07 22:24:41 +0900 | [diff] [blame] | 2683 | } |
| 2684 | |
| 2685 | /* recalculate the number of segments */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2686 | blk_recalc_rq_segments(req); |
Tejun Heo | 2e46e8b | 2009-05-07 22:24:41 +0900 | [diff] [blame] | 2687 | |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2688 | return true; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2689 | } |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2690 | EXPORT_SYMBOL_GPL(blk_update_request); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2691 | |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2692 | static bool blk_update_bidi_request(struct request *rq, int error, |
| 2693 | unsigned int nr_bytes, |
| 2694 | unsigned int bidi_bytes) |
Tejun Heo | 5efccd1 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2695 | { |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2696 | if (blk_update_request(rq, error, nr_bytes)) |
| 2697 | return true; |
Tejun Heo | 5efccd1 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2698 | |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2699 | /* Bidi request must be completed as a whole */ |
| 2700 | if (unlikely(blk_bidi_rq(rq)) && |
| 2701 | blk_update_request(rq->next_rq, error, bidi_bytes)) |
| 2702 | return true; |
Tejun Heo | 5efccd1 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2703 | |
Jens Axboe | e2e1a14 | 2010-06-09 10:42:09 +0200 | [diff] [blame] | 2704 | if (blk_queue_add_random(rq->q)) |
| 2705 | add_disk_randomness(rq->rq_disk); |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2706 | |
| 2707 | return false; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2708 | } |
| 2709 | |
James Bottomley | 28018c2 | 2010-07-01 19:49:17 +0900 | [diff] [blame] | 2710 | /** |
| 2711 | * blk_unprep_request - unprepare a request |
| 2712 | * @req: the request |
| 2713 | * |
| 2714 | * This function makes a request ready for complete resubmission (or |
| 2715 | * completion). It happens only after all error handling is complete, |
| 2716 | * so represents the appropriate moment to deallocate any resources |
| 2717 | * that were allocated to the request in the prep_rq_fn. The queue |
| 2718 | * lock is held when calling this. |
| 2719 | */ |
| 2720 | void blk_unprep_request(struct request *req) |
| 2721 | { |
| 2722 | struct request_queue *q = req->q; |
| 2723 | |
| 2724 | req->cmd_flags &= ~REQ_DONTPREP; |
| 2725 | if (q->unprep_rq_fn) |
| 2726 | q->unprep_rq_fn(q, req); |
| 2727 | } |
| 2728 | EXPORT_SYMBOL_GPL(blk_unprep_request); |
| 2729 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2730 | /* |
| 2731 | * queue lock must be held |
| 2732 | */ |
Christoph Hellwig | 1212007 | 2014-04-16 09:44:59 +0200 | [diff] [blame] | 2733 | void blk_finish_request(struct request *req, int error) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2734 | { |
Christoph Hellwig | 125c99b | 2014-11-03 12:47:47 +0100 | [diff] [blame] | 2735 | if (req->cmd_flags & REQ_QUEUED) |
Kiyoshi Ueda | b828623 | 2007-12-11 17:53:24 -0500 | [diff] [blame] | 2736 | blk_queue_end_tag(req->q, req); |
| 2737 | |
James Bottomley | ba396a6 | 2009-05-27 14:17:08 +0200 | [diff] [blame] | 2738 | BUG_ON(blk_queued_rq(req)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2739 | |
Christoph Hellwig | 33659eb | 2010-08-07 18:17:56 +0200 | [diff] [blame] | 2740 | if (unlikely(laptop_mode) && req->cmd_type == REQ_TYPE_FS) |
Matthew Garrett | 31373d0 | 2010-04-06 14:25:14 +0200 | [diff] [blame] | 2741 | laptop_io_completion(&req->q->backing_dev_info); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2742 | |
Mike Anderson | e78042e | 2008-10-30 02:16:20 -0700 | [diff] [blame] | 2743 | blk_delete_timer(req); |
| 2744 | |
James Bottomley | 28018c2 | 2010-07-01 19:49:17 +0900 | [diff] [blame] | 2745 | if (req->cmd_flags & REQ_DONTPREP) |
| 2746 | blk_unprep_request(req); |
| 2747 | |
Jens Axboe | bc58ba9 | 2009-01-23 10:54:44 +0100 | [diff] [blame] | 2748 | blk_account_io_done(req); |
Kiyoshi Ueda | b828623 | 2007-12-11 17:53:24 -0500 | [diff] [blame] | 2749 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2750 | if (req->end_io) |
Tejun Heo | 8ffdc65 | 2006-01-06 09:49:03 +0100 | [diff] [blame] | 2751 | req->end_io(req, error); |
Kiyoshi Ueda | b828623 | 2007-12-11 17:53:24 -0500 | [diff] [blame] | 2752 | else { |
| 2753 | if (blk_bidi_rq(req)) |
| 2754 | __blk_put_request(req->next_rq->q, req->next_rq); |
| 2755 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2756 | __blk_put_request(req->q, req); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2757 | } |
| 2758 | } |
Christoph Hellwig | 1212007 | 2014-04-16 09:44:59 +0200 | [diff] [blame] | 2759 | EXPORT_SYMBOL(blk_finish_request); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2760 | |
Kiyoshi Ueda | 3b11313 | 2007-12-11 17:41:17 -0500 | [diff] [blame] | 2761 | /** |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2762 | * blk_end_bidi_request - Complete a bidi request |
| 2763 | * @rq: the request to complete |
Randy Dunlap | 710027a | 2008-08-19 20:13:11 +0200 | [diff] [blame] | 2764 | * @error: %0 for success, < %0 for error |
Kiyoshi Ueda | e3a04fe | 2007-12-11 17:51:46 -0500 | [diff] [blame] | 2765 | * @nr_bytes: number of bytes to complete @rq |
| 2766 | * @bidi_bytes: number of bytes to complete @rq->next_rq |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2767 | * |
| 2768 | * Description: |
| 2769 | * Ends I/O on a number of bytes attached to @rq and @rq->next_rq. |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2770 | * Drivers that supports bidi can safely call this member for any |
| 2771 | * type of request, bidi or uni. In the later case @bidi_bytes is |
| 2772 | * just ignored. |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2773 | * |
| 2774 | * Return: |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2775 | * %false - we are done with this request |
| 2776 | * %true - still buffers pending for this request |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2777 | **/ |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2778 | static bool blk_end_bidi_request(struct request *rq, int error, |
| 2779 | unsigned int nr_bytes, unsigned int bidi_bytes) |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2780 | { |
| 2781 | struct request_queue *q = rq->q; |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2782 | unsigned long flags; |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2783 | |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2784 | if (blk_update_bidi_request(rq, error, nr_bytes, bidi_bytes)) |
| 2785 | return true; |
Kiyoshi Ueda | e19a3ab | 2007-12-11 17:51:02 -0500 | [diff] [blame] | 2786 | |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2787 | spin_lock_irqsave(q->queue_lock, flags); |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2788 | blk_finish_request(rq, error); |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2789 | spin_unlock_irqrestore(q->queue_lock, flags); |
| 2790 | |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2791 | return false; |
Kiyoshi Ueda | e3a04fe | 2007-12-11 17:51:46 -0500 | [diff] [blame] | 2792 | } |
Kiyoshi Ueda | e3a04fe | 2007-12-11 17:51:46 -0500 | [diff] [blame] | 2793 | |
| 2794 | /** |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2795 | * __blk_end_bidi_request - Complete a bidi request with queue lock held |
| 2796 | * @rq: the request to complete |
| 2797 | * @error: %0 for success, < %0 for error |
| 2798 | * @nr_bytes: number of bytes to complete @rq |
| 2799 | * @bidi_bytes: number of bytes to complete @rq->next_rq |
Tejun Heo | 5efccd1 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2800 | * |
| 2801 | * Description: |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2802 | * Identical to blk_end_bidi_request() except that queue lock is |
| 2803 | * assumed to be locked on entry and remains so on return. |
Tejun Heo | 5efccd1 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2804 | * |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2805 | * Return: |
| 2806 | * %false - we are done with this request |
| 2807 | * %true - still buffers pending for this request |
Tejun Heo | 5efccd1 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2808 | **/ |
Jeff Moyer | 4853aba | 2011-08-15 21:37:25 +0200 | [diff] [blame] | 2809 | bool __blk_end_bidi_request(struct request *rq, int error, |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2810 | unsigned int nr_bytes, unsigned int bidi_bytes) |
Tejun Heo | 5efccd1 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2811 | { |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2812 | if (blk_update_bidi_request(rq, error, nr_bytes, bidi_bytes)) |
| 2813 | return true; |
Tejun Heo | 5efccd1 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2814 | |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2815 | blk_finish_request(rq, error); |
Tejun Heo | 5efccd1 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2816 | |
Tejun Heo | 2e60e02 | 2009-04-23 11:05:18 +0900 | [diff] [blame] | 2817 | return false; |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2818 | } |
| 2819 | |
| 2820 | /** |
| 2821 | * blk_end_request - Helper function for drivers to complete the request. |
| 2822 | * @rq: the request being processed |
| 2823 | * @error: %0 for success, < %0 for error |
| 2824 | * @nr_bytes: number of bytes to complete |
| 2825 | * |
| 2826 | * Description: |
| 2827 | * Ends I/O on a number of bytes attached to @rq. |
| 2828 | * If @rq has leftover, sets it up for the next range of segments. |
| 2829 | * |
| 2830 | * Return: |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2831 | * %false - we are done with this request |
| 2832 | * %true - still buffers pending for this request |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2833 | **/ |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2834 | bool blk_end_request(struct request *rq, int error, unsigned int nr_bytes) |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2835 | { |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2836 | return blk_end_bidi_request(rq, error, nr_bytes, 0); |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2837 | } |
Jens Axboe | 56ad174 | 2009-07-28 22:11:24 +0200 | [diff] [blame] | 2838 | EXPORT_SYMBOL(blk_end_request); |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2839 | |
| 2840 | /** |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2841 | * blk_end_request_all - Helper function for drives to finish the request. |
| 2842 | * @rq: the request to finish |
Randy Dunlap | 8ebf975 | 2009-06-11 20:00:41 -0700 | [diff] [blame] | 2843 | * @error: %0 for success, < %0 for error |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2844 | * |
| 2845 | * Description: |
| 2846 | * Completely finish @rq. |
| 2847 | */ |
| 2848 | void blk_end_request_all(struct request *rq, int error) |
| 2849 | { |
| 2850 | bool pending; |
| 2851 | unsigned int bidi_bytes = 0; |
| 2852 | |
| 2853 | if (unlikely(blk_bidi_rq(rq))) |
| 2854 | bidi_bytes = blk_rq_bytes(rq->next_rq); |
| 2855 | |
| 2856 | pending = blk_end_bidi_request(rq, error, blk_rq_bytes(rq), bidi_bytes); |
| 2857 | BUG_ON(pending); |
| 2858 | } |
Jens Axboe | 56ad174 | 2009-07-28 22:11:24 +0200 | [diff] [blame] | 2859 | EXPORT_SYMBOL(blk_end_request_all); |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2860 | |
| 2861 | /** |
| 2862 | * blk_end_request_cur - Helper function to finish the current request chunk. |
| 2863 | * @rq: the request to finish the current chunk for |
Randy Dunlap | 8ebf975 | 2009-06-11 20:00:41 -0700 | [diff] [blame] | 2864 | * @error: %0 for success, < %0 for error |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2865 | * |
| 2866 | * Description: |
| 2867 | * Complete the current consecutively mapped chunk from @rq. |
| 2868 | * |
| 2869 | * Return: |
| 2870 | * %false - we are done with this request |
| 2871 | * %true - still buffers pending for this request |
| 2872 | */ |
| 2873 | bool blk_end_request_cur(struct request *rq, int error) |
| 2874 | { |
| 2875 | return blk_end_request(rq, error, blk_rq_cur_bytes(rq)); |
| 2876 | } |
Jens Axboe | 56ad174 | 2009-07-28 22:11:24 +0200 | [diff] [blame] | 2877 | EXPORT_SYMBOL(blk_end_request_cur); |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2878 | |
| 2879 | /** |
Tejun Heo | 80a761f | 2009-07-03 17:48:17 +0900 | [diff] [blame] | 2880 | * blk_end_request_err - Finish a request till the next failure boundary. |
| 2881 | * @rq: the request to finish till the next failure boundary for |
| 2882 | * @error: must be negative errno |
| 2883 | * |
| 2884 | * Description: |
| 2885 | * Complete @rq till the next failure boundary. |
| 2886 | * |
| 2887 | * Return: |
| 2888 | * %false - we are done with this request |
| 2889 | * %true - still buffers pending for this request |
| 2890 | */ |
| 2891 | bool blk_end_request_err(struct request *rq, int error) |
| 2892 | { |
| 2893 | WARN_ON(error >= 0); |
| 2894 | return blk_end_request(rq, error, blk_rq_err_bytes(rq)); |
| 2895 | } |
| 2896 | EXPORT_SYMBOL_GPL(blk_end_request_err); |
| 2897 | |
| 2898 | /** |
Kiyoshi Ueda | e19a3ab | 2007-12-11 17:51:02 -0500 | [diff] [blame] | 2899 | * __blk_end_request - Helper function for drivers to complete the request. |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2900 | * @rq: the request being processed |
Kiyoshi Ueda | e19a3ab | 2007-12-11 17:51:02 -0500 | [diff] [blame] | 2901 | * @error: %0 for success, < %0 for error |
| 2902 | * @nr_bytes: number of bytes to complete |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2903 | * |
| 2904 | * Description: |
| 2905 | * Must be called with queue lock held unlike blk_end_request(). |
| 2906 | * |
| 2907 | * Return: |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2908 | * %false - we are done with this request |
| 2909 | * %true - still buffers pending for this request |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2910 | **/ |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2911 | bool __blk_end_request(struct request *rq, int error, unsigned int nr_bytes) |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2912 | { |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2913 | return __blk_end_bidi_request(rq, error, nr_bytes, 0); |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2914 | } |
Jens Axboe | 56ad174 | 2009-07-28 22:11:24 +0200 | [diff] [blame] | 2915 | EXPORT_SYMBOL(__blk_end_request); |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2916 | |
| 2917 | /** |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2918 | * __blk_end_request_all - Helper function for drives to finish the request. |
| 2919 | * @rq: the request to finish |
Randy Dunlap | 8ebf975 | 2009-06-11 20:00:41 -0700 | [diff] [blame] | 2920 | * @error: %0 for success, < %0 for error |
Kiyoshi Ueda | 336cdb4 | 2007-12-11 17:40:30 -0500 | [diff] [blame] | 2921 | * |
| 2922 | * Description: |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2923 | * Completely finish @rq. Must be called with queue lock held. |
Kiyoshi Ueda | 32fab44 | 2008-09-18 10:45:09 -0400 | [diff] [blame] | 2924 | */ |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2925 | void __blk_end_request_all(struct request *rq, int error) |
Kiyoshi Ueda | 32fab44 | 2008-09-18 10:45:09 -0400 | [diff] [blame] | 2926 | { |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2927 | bool pending; |
| 2928 | unsigned int bidi_bytes = 0; |
| 2929 | |
| 2930 | if (unlikely(blk_bidi_rq(rq))) |
| 2931 | bidi_bytes = blk_rq_bytes(rq->next_rq); |
| 2932 | |
| 2933 | pending = __blk_end_bidi_request(rq, error, blk_rq_bytes(rq), bidi_bytes); |
| 2934 | BUG_ON(pending); |
Kiyoshi Ueda | 32fab44 | 2008-09-18 10:45:09 -0400 | [diff] [blame] | 2935 | } |
Jens Axboe | 56ad174 | 2009-07-28 22:11:24 +0200 | [diff] [blame] | 2936 | EXPORT_SYMBOL(__blk_end_request_all); |
Kiyoshi Ueda | 32fab44 | 2008-09-18 10:45:09 -0400 | [diff] [blame] | 2937 | |
| 2938 | /** |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2939 | * __blk_end_request_cur - Helper function to finish the current request chunk. |
| 2940 | * @rq: the request to finish the current chunk for |
Randy Dunlap | 8ebf975 | 2009-06-11 20:00:41 -0700 | [diff] [blame] | 2941 | * @error: %0 for success, < %0 for error |
Kiyoshi Ueda | e19a3ab | 2007-12-11 17:51:02 -0500 | [diff] [blame] | 2942 | * |
| 2943 | * Description: |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2944 | * Complete the current consecutively mapped chunk from @rq. Must |
| 2945 | * be called with queue lock held. |
Kiyoshi Ueda | e19a3ab | 2007-12-11 17:51:02 -0500 | [diff] [blame] | 2946 | * |
| 2947 | * Return: |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2948 | * %false - we are done with this request |
| 2949 | * %true - still buffers pending for this request |
| 2950 | */ |
| 2951 | bool __blk_end_request_cur(struct request *rq, int error) |
Kiyoshi Ueda | e19a3ab | 2007-12-11 17:51:02 -0500 | [diff] [blame] | 2952 | { |
FUJITA Tomonori | b1f7449 | 2009-05-11 17:56:09 +0900 | [diff] [blame] | 2953 | return __blk_end_request(rq, error, blk_rq_cur_bytes(rq)); |
Kiyoshi Ueda | e19a3ab | 2007-12-11 17:51:02 -0500 | [diff] [blame] | 2954 | } |
Jens Axboe | 56ad174 | 2009-07-28 22:11:24 +0200 | [diff] [blame] | 2955 | EXPORT_SYMBOL(__blk_end_request_cur); |
Kiyoshi Ueda | e19a3ab | 2007-12-11 17:51:02 -0500 | [diff] [blame] | 2956 | |
Tejun Heo | 80a761f | 2009-07-03 17:48:17 +0900 | [diff] [blame] | 2957 | /** |
| 2958 | * __blk_end_request_err - Finish a request till the next failure boundary. |
| 2959 | * @rq: the request to finish till the next failure boundary for |
| 2960 | * @error: must be negative errno |
| 2961 | * |
| 2962 | * Description: |
| 2963 | * Complete @rq till the next failure boundary. Must be called |
| 2964 | * with queue lock held. |
| 2965 | * |
| 2966 | * Return: |
| 2967 | * %false - we are done with this request |
| 2968 | * %true - still buffers pending for this request |
| 2969 | */ |
| 2970 | bool __blk_end_request_err(struct request *rq, int error) |
| 2971 | { |
| 2972 | WARN_ON(error >= 0); |
| 2973 | return __blk_end_request(rq, error, blk_rq_err_bytes(rq)); |
| 2974 | } |
| 2975 | EXPORT_SYMBOL_GPL(__blk_end_request_err); |
| 2976 | |
Jens Axboe | 86db1e2 | 2008-01-29 14:53:40 +0100 | [diff] [blame] | 2977 | void blk_rq_bio_prep(struct request_queue *q, struct request *rq, |
| 2978 | struct bio *bio) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2979 | { |
Tejun Heo | a82afdf | 2009-07-03 17:48:16 +0900 | [diff] [blame] | 2980 | /* Bit 0 (R/W) is identical in rq->cmd_flags and bio->bi_rw */ |
Christoph Hellwig | 7b6d91d | 2010-08-07 18:20:39 +0200 | [diff] [blame] | 2981 | rq->cmd_flags |= bio->bi_rw & REQ_WRITE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2982 | |
Jens Axboe | b4f42e2 | 2014-04-10 09:46:28 -0600 | [diff] [blame] | 2983 | if (bio_has_data(bio)) |
David Woodhouse | fb2dce8 | 2008-08-05 18:01:53 +0100 | [diff] [blame] | 2984 | rq->nr_phys_segments = bio_phys_segments(q, bio); |
Jens Axboe | b4f42e2 | 2014-04-10 09:46:28 -0600 | [diff] [blame] | 2985 | |
Kent Overstreet | 4f024f3 | 2013-10-11 15:44:27 -0700 | [diff] [blame] | 2986 | rq->__data_len = bio->bi_iter.bi_size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2987 | rq->bio = rq->biotail = bio; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2988 | |
NeilBrown | 6684657 | 2007-08-16 13:31:28 +0200 | [diff] [blame] | 2989 | if (bio->bi_bdev) |
| 2990 | rq->rq_disk = bio->bi_bdev->bd_disk; |
| 2991 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2992 | |
Ilya Loginov | 2d4dc89 | 2009-11-26 09:16:19 +0100 | [diff] [blame] | 2993 | #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE |
| 2994 | /** |
| 2995 | * rq_flush_dcache_pages - Helper function to flush all pages in a request |
| 2996 | * @rq: the request to be flushed |
| 2997 | * |
| 2998 | * Description: |
| 2999 | * Flush all pages in @rq. |
| 3000 | */ |
| 3001 | void rq_flush_dcache_pages(struct request *rq) |
| 3002 | { |
| 3003 | struct req_iterator iter; |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 3004 | struct bio_vec bvec; |
Ilya Loginov | 2d4dc89 | 2009-11-26 09:16:19 +0100 | [diff] [blame] | 3005 | |
| 3006 | rq_for_each_segment(bvec, rq, iter) |
Kent Overstreet | 7988613 | 2013-11-23 17:19:00 -0800 | [diff] [blame] | 3007 | flush_dcache_page(bvec.bv_page); |
Ilya Loginov | 2d4dc89 | 2009-11-26 09:16:19 +0100 | [diff] [blame] | 3008 | } |
| 3009 | EXPORT_SYMBOL_GPL(rq_flush_dcache_pages); |
| 3010 | #endif |
| 3011 | |
Kiyoshi Ueda | ef9e3fa | 2008-10-01 16:12:15 +0200 | [diff] [blame] | 3012 | /** |
| 3013 | * blk_lld_busy - Check if underlying low-level drivers of a device are busy |
| 3014 | * @q : the queue of the device being checked |
| 3015 | * |
| 3016 | * Description: |
| 3017 | * Check if underlying low-level drivers of a device are busy. |
| 3018 | * If the drivers want to export their busy state, they must set own |
| 3019 | * exporting function using blk_queue_lld_busy() first. |
| 3020 | * |
| 3021 | * Basically, this function is used only by request stacking drivers |
| 3022 | * to stop dispatching requests to underlying devices when underlying |
| 3023 | * devices are busy. This behavior helps more I/O merging on the queue |
| 3024 | * of the request stacking driver and prevents I/O throughput regression |
| 3025 | * on burst I/O load. |
| 3026 | * |
| 3027 | * Return: |
| 3028 | * 0 - Not busy (The request stacking driver should dispatch request) |
| 3029 | * 1 - Busy (The request stacking driver should stop dispatching request) |
| 3030 | */ |
| 3031 | int blk_lld_busy(struct request_queue *q) |
| 3032 | { |
| 3033 | if (q->lld_busy_fn) |
| 3034 | return q->lld_busy_fn(q); |
| 3035 | |
| 3036 | return 0; |
| 3037 | } |
| 3038 | EXPORT_SYMBOL_GPL(blk_lld_busy); |
| 3039 | |
Mike Snitzer | 78d8e58 | 2015-06-26 10:01:13 -0400 | [diff] [blame] | 3040 | /** |
| 3041 | * blk_rq_unprep_clone - Helper function to free all bios in a cloned request |
| 3042 | * @rq: the clone request to be cleaned up |
| 3043 | * |
| 3044 | * Description: |
| 3045 | * Free all bios in @rq for a cloned request. |
| 3046 | */ |
| 3047 | void blk_rq_unprep_clone(struct request *rq) |
| 3048 | { |
| 3049 | struct bio *bio; |
| 3050 | |
| 3051 | while ((bio = rq->bio) != NULL) { |
| 3052 | rq->bio = bio->bi_next; |
| 3053 | |
| 3054 | bio_put(bio); |
| 3055 | } |
| 3056 | } |
| 3057 | EXPORT_SYMBOL_GPL(blk_rq_unprep_clone); |
| 3058 | |
| 3059 | /* |
| 3060 | * Copy attributes of the original request to the clone request. |
| 3061 | * The actual data parts (e.g. ->cmd, ->sense) are not copied. |
| 3062 | */ |
| 3063 | static void __blk_rq_prep_clone(struct request *dst, struct request *src) |
Kiyoshi Ueda | b0fd271 | 2009-06-11 13:10:16 +0200 | [diff] [blame] | 3064 | { |
| 3065 | dst->cpu = src->cpu; |
Mike Snitzer | 78d8e58 | 2015-06-26 10:01:13 -0400 | [diff] [blame] | 3066 | dst->cmd_flags |= (src->cmd_flags & REQ_CLONE_MASK) | REQ_NOMERGE; |
Kiyoshi Ueda | b0fd271 | 2009-06-11 13:10:16 +0200 | [diff] [blame] | 3067 | dst->cmd_type = src->cmd_type; |
| 3068 | dst->__sector = blk_rq_pos(src); |
| 3069 | dst->__data_len = blk_rq_bytes(src); |
| 3070 | dst->nr_phys_segments = src->nr_phys_segments; |
| 3071 | dst->ioprio = src->ioprio; |
| 3072 | dst->extra_len = src->extra_len; |
Mike Snitzer | 78d8e58 | 2015-06-26 10:01:13 -0400 | [diff] [blame] | 3073 | } |
| 3074 | |
| 3075 | /** |
| 3076 | * blk_rq_prep_clone - Helper function to setup clone request |
| 3077 | * @rq: the request to be setup |
| 3078 | * @rq_src: original request to be cloned |
| 3079 | * @bs: bio_set that bios for clone are allocated from |
| 3080 | * @gfp_mask: memory allocation mask for bio |
| 3081 | * @bio_ctr: setup function to be called for each clone bio. |
| 3082 | * Returns %0 for success, non %0 for failure. |
| 3083 | * @data: private data to be passed to @bio_ctr |
| 3084 | * |
| 3085 | * Description: |
| 3086 | * Clones bios in @rq_src to @rq, and copies attributes of @rq_src to @rq. |
| 3087 | * The actual data parts of @rq_src (e.g. ->cmd, ->sense) |
| 3088 | * are not copied, and copying such parts is the caller's responsibility. |
| 3089 | * Also, pages which the original bios are pointing to are not copied |
| 3090 | * and the cloned bios just point same pages. |
| 3091 | * So cloned bios must be completed before original bios, which means |
| 3092 | * the caller must complete @rq before @rq_src. |
| 3093 | */ |
| 3094 | int blk_rq_prep_clone(struct request *rq, struct request *rq_src, |
| 3095 | struct bio_set *bs, gfp_t gfp_mask, |
| 3096 | int (*bio_ctr)(struct bio *, struct bio *, void *), |
| 3097 | void *data) |
| 3098 | { |
| 3099 | struct bio *bio, *bio_src; |
| 3100 | |
| 3101 | if (!bs) |
| 3102 | bs = fs_bio_set; |
| 3103 | |
| 3104 | __rq_for_each_bio(bio_src, rq_src) { |
| 3105 | bio = bio_clone_fast(bio_src, gfp_mask, bs); |
| 3106 | if (!bio) |
| 3107 | goto free_and_out; |
| 3108 | |
| 3109 | if (bio_ctr && bio_ctr(bio, bio_src, data)) |
| 3110 | goto free_and_out; |
| 3111 | |
| 3112 | if (rq->bio) { |
| 3113 | rq->biotail->bi_next = bio; |
| 3114 | rq->biotail = bio; |
| 3115 | } else |
| 3116 | rq->bio = rq->biotail = bio; |
| 3117 | } |
| 3118 | |
| 3119 | __blk_rq_prep_clone(rq, rq_src); |
| 3120 | |
| 3121 | return 0; |
| 3122 | |
| 3123 | free_and_out: |
| 3124 | if (bio) |
| 3125 | bio_put(bio); |
| 3126 | blk_rq_unprep_clone(rq); |
| 3127 | |
| 3128 | return -ENOMEM; |
Kiyoshi Ueda | b0fd271 | 2009-06-11 13:10:16 +0200 | [diff] [blame] | 3129 | } |
| 3130 | EXPORT_SYMBOL_GPL(blk_rq_prep_clone); |
| 3131 | |
Jens Axboe | 59c3d45 | 2014-04-08 09:15:35 -0600 | [diff] [blame] | 3132 | int kblockd_schedule_work(struct work_struct *work) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3133 | { |
| 3134 | return queue_work(kblockd_workqueue, work); |
| 3135 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3136 | EXPORT_SYMBOL(kblockd_schedule_work); |
| 3137 | |
Jens Axboe | 59c3d45 | 2014-04-08 09:15:35 -0600 | [diff] [blame] | 3138 | int kblockd_schedule_delayed_work(struct delayed_work *dwork, |
| 3139 | unsigned long delay) |
Vivek Goyal | e43473b | 2010-09-15 17:06:35 -0400 | [diff] [blame] | 3140 | { |
| 3141 | return queue_delayed_work(kblockd_workqueue, dwork, delay); |
| 3142 | } |
| 3143 | EXPORT_SYMBOL(kblockd_schedule_delayed_work); |
| 3144 | |
Jens Axboe | 8ab1459 | 2014-04-08 09:17:40 -0600 | [diff] [blame] | 3145 | int kblockd_schedule_delayed_work_on(int cpu, struct delayed_work *dwork, |
| 3146 | unsigned long delay) |
| 3147 | { |
| 3148 | return queue_delayed_work_on(cpu, kblockd_workqueue, dwork, delay); |
| 3149 | } |
| 3150 | EXPORT_SYMBOL(kblockd_schedule_delayed_work_on); |
| 3151 | |
Suresh Jayaraman | 75df713 | 2011-09-21 10:00:16 +0200 | [diff] [blame] | 3152 | /** |
| 3153 | * blk_start_plug - initialize blk_plug and track it inside the task_struct |
| 3154 | * @plug: The &struct blk_plug that needs to be initialized |
| 3155 | * |
| 3156 | * Description: |
| 3157 | * Tracking blk_plug inside the task_struct will help with auto-flushing the |
| 3158 | * pending I/O should the task end up blocking between blk_start_plug() and |
| 3159 | * blk_finish_plug(). This is important from a performance perspective, but |
| 3160 | * also ensures that we don't deadlock. For instance, if the task is blocking |
| 3161 | * for a memory allocation, memory reclaim could end up wanting to free a |
| 3162 | * page belonging to that request that is currently residing in our private |
| 3163 | * plug. By flushing the pending I/O when the process goes to sleep, we avoid |
| 3164 | * this kind of deadlock. |
| 3165 | */ |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3166 | void blk_start_plug(struct blk_plug *plug) |
| 3167 | { |
| 3168 | struct task_struct *tsk = current; |
| 3169 | |
Shaohua Li | dd6cf3e | 2015-05-08 10:51:28 -0700 | [diff] [blame] | 3170 | /* |
| 3171 | * If this is a nested plug, don't actually assign it. |
| 3172 | */ |
| 3173 | if (tsk->plug) |
| 3174 | return; |
| 3175 | |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3176 | INIT_LIST_HEAD(&plug->list); |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 3177 | INIT_LIST_HEAD(&plug->mq_list); |
NeilBrown | 048c937 | 2011-04-18 09:52:22 +0200 | [diff] [blame] | 3178 | INIT_LIST_HEAD(&plug->cb_list); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3179 | /* |
Shaohua Li | dd6cf3e | 2015-05-08 10:51:28 -0700 | [diff] [blame] | 3180 | * Store ordering should not be needed here, since a potential |
| 3181 | * preempt will imply a full memory barrier |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3182 | */ |
Shaohua Li | dd6cf3e | 2015-05-08 10:51:28 -0700 | [diff] [blame] | 3183 | tsk->plug = plug; |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3184 | } |
| 3185 | EXPORT_SYMBOL(blk_start_plug); |
| 3186 | |
| 3187 | static int plug_rq_cmp(void *priv, struct list_head *a, struct list_head *b) |
| 3188 | { |
| 3189 | struct request *rqa = container_of(a, struct request, queuelist); |
| 3190 | struct request *rqb = container_of(b, struct request, queuelist); |
| 3191 | |
Jianpeng Ma | 975927b | 2012-10-25 21:58:17 +0200 | [diff] [blame] | 3192 | return !(rqa->q < rqb->q || |
| 3193 | (rqa->q == rqb->q && blk_rq_pos(rqa) < blk_rq_pos(rqb))); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3194 | } |
| 3195 | |
Jens Axboe | 49cac01 | 2011-04-16 13:51:05 +0200 | [diff] [blame] | 3196 | /* |
| 3197 | * If 'from_schedule' is true, then postpone the dispatch of requests |
| 3198 | * until a safe kblockd context. We due this to avoid accidental big |
| 3199 | * additional stack usage in driver dispatch, in places where the originally |
| 3200 | * plugger did not intend it. |
| 3201 | */ |
Jens Axboe | f660378 | 2011-04-15 15:49:07 +0200 | [diff] [blame] | 3202 | static void queue_unplugged(struct request_queue *q, unsigned int depth, |
Jens Axboe | 49cac01 | 2011-04-16 13:51:05 +0200 | [diff] [blame] | 3203 | bool from_schedule) |
Jens Axboe | 99e2259 | 2011-04-18 09:59:55 +0200 | [diff] [blame] | 3204 | __releases(q->queue_lock) |
Jens Axboe | 94b5eb2 | 2011-04-12 10:12:19 +0200 | [diff] [blame] | 3205 | { |
Jens Axboe | 49cac01 | 2011-04-16 13:51:05 +0200 | [diff] [blame] | 3206 | trace_block_unplug(q, depth, !from_schedule); |
Jens Axboe | 99e2259 | 2011-04-18 09:59:55 +0200 | [diff] [blame] | 3207 | |
Bart Van Assche | 7046057 | 2012-11-28 13:45:56 +0100 | [diff] [blame] | 3208 | if (from_schedule) |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 3209 | blk_run_queue_async(q); |
Bart Van Assche | 7046057 | 2012-11-28 13:45:56 +0100 | [diff] [blame] | 3210 | else |
Christoph Hellwig | 24ecfbe | 2011-04-18 11:41:33 +0200 | [diff] [blame] | 3211 | __blk_run_queue(q); |
Bart Van Assche | 7046057 | 2012-11-28 13:45:56 +0100 | [diff] [blame] | 3212 | spin_unlock(q->queue_lock); |
Jens Axboe | 94b5eb2 | 2011-04-12 10:12:19 +0200 | [diff] [blame] | 3213 | } |
| 3214 | |
NeilBrown | 74018dc | 2012-07-31 09:08:15 +0200 | [diff] [blame] | 3215 | static void flush_plug_callbacks(struct blk_plug *plug, bool from_schedule) |
NeilBrown | 048c937 | 2011-04-18 09:52:22 +0200 | [diff] [blame] | 3216 | { |
| 3217 | LIST_HEAD(callbacks); |
| 3218 | |
Shaohua Li | 2a7d555 | 2012-07-31 09:08:15 +0200 | [diff] [blame] | 3219 | while (!list_empty(&plug->cb_list)) { |
| 3220 | list_splice_init(&plug->cb_list, &callbacks); |
NeilBrown | 048c937 | 2011-04-18 09:52:22 +0200 | [diff] [blame] | 3221 | |
Shaohua Li | 2a7d555 | 2012-07-31 09:08:15 +0200 | [diff] [blame] | 3222 | while (!list_empty(&callbacks)) { |
| 3223 | struct blk_plug_cb *cb = list_first_entry(&callbacks, |
NeilBrown | 048c937 | 2011-04-18 09:52:22 +0200 | [diff] [blame] | 3224 | struct blk_plug_cb, |
| 3225 | list); |
Shaohua Li | 2a7d555 | 2012-07-31 09:08:15 +0200 | [diff] [blame] | 3226 | list_del(&cb->list); |
NeilBrown | 74018dc | 2012-07-31 09:08:15 +0200 | [diff] [blame] | 3227 | cb->callback(cb, from_schedule); |
Shaohua Li | 2a7d555 | 2012-07-31 09:08:15 +0200 | [diff] [blame] | 3228 | } |
NeilBrown | 048c937 | 2011-04-18 09:52:22 +0200 | [diff] [blame] | 3229 | } |
| 3230 | } |
| 3231 | |
NeilBrown | 9cbb175 | 2012-07-31 09:08:14 +0200 | [diff] [blame] | 3232 | struct blk_plug_cb *blk_check_plugged(blk_plug_cb_fn unplug, void *data, |
| 3233 | int size) |
| 3234 | { |
| 3235 | struct blk_plug *plug = current->plug; |
| 3236 | struct blk_plug_cb *cb; |
| 3237 | |
| 3238 | if (!plug) |
| 3239 | return NULL; |
| 3240 | |
| 3241 | list_for_each_entry(cb, &plug->cb_list, list) |
| 3242 | if (cb->callback == unplug && cb->data == data) |
| 3243 | return cb; |
| 3244 | |
| 3245 | /* Not currently on the callback list */ |
| 3246 | BUG_ON(size < sizeof(*cb)); |
| 3247 | cb = kzalloc(size, GFP_ATOMIC); |
| 3248 | if (cb) { |
| 3249 | cb->data = data; |
| 3250 | cb->callback = unplug; |
| 3251 | list_add(&cb->list, &plug->cb_list); |
| 3252 | } |
| 3253 | return cb; |
| 3254 | } |
| 3255 | EXPORT_SYMBOL(blk_check_plugged); |
| 3256 | |
Jens Axboe | 49cac01 | 2011-04-16 13:51:05 +0200 | [diff] [blame] | 3257 | void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3258 | { |
| 3259 | struct request_queue *q; |
| 3260 | unsigned long flags; |
| 3261 | struct request *rq; |
NeilBrown | 109b812 | 2011-04-11 14:13:10 +0200 | [diff] [blame] | 3262 | LIST_HEAD(list); |
Jens Axboe | 94b5eb2 | 2011-04-12 10:12:19 +0200 | [diff] [blame] | 3263 | unsigned int depth; |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3264 | |
NeilBrown | 74018dc | 2012-07-31 09:08:15 +0200 | [diff] [blame] | 3265 | flush_plug_callbacks(plug, from_schedule); |
Jens Axboe | 320ae51 | 2013-10-24 09:20:05 +0100 | [diff] [blame] | 3266 | |
| 3267 | if (!list_empty(&plug->mq_list)) |
| 3268 | blk_mq_flush_plug_list(plug, from_schedule); |
| 3269 | |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3270 | if (list_empty(&plug->list)) |
| 3271 | return; |
| 3272 | |
NeilBrown | 109b812 | 2011-04-11 14:13:10 +0200 | [diff] [blame] | 3273 | list_splice_init(&plug->list, &list); |
| 3274 | |
Jianpeng Ma | 422765c | 2013-01-11 14:46:09 +0100 | [diff] [blame] | 3275 | list_sort(NULL, &list, plug_rq_cmp); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3276 | |
| 3277 | q = NULL; |
Jens Axboe | 94b5eb2 | 2011-04-12 10:12:19 +0200 | [diff] [blame] | 3278 | depth = 0; |
Jens Axboe | 1881127 | 2011-04-12 10:11:24 +0200 | [diff] [blame] | 3279 | |
| 3280 | /* |
| 3281 | * Save and disable interrupts here, to avoid doing it for every |
| 3282 | * queue lock we have to take. |
| 3283 | */ |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3284 | local_irq_save(flags); |
NeilBrown | 109b812 | 2011-04-11 14:13:10 +0200 | [diff] [blame] | 3285 | while (!list_empty(&list)) { |
| 3286 | rq = list_entry_rq(list.next); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3287 | list_del_init(&rq->queuelist); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3288 | BUG_ON(!rq->q); |
| 3289 | if (rq->q != q) { |
Jens Axboe | 99e2259 | 2011-04-18 09:59:55 +0200 | [diff] [blame] | 3290 | /* |
| 3291 | * This drops the queue lock |
| 3292 | */ |
| 3293 | if (q) |
Jens Axboe | 49cac01 | 2011-04-16 13:51:05 +0200 | [diff] [blame] | 3294 | queue_unplugged(q, depth, from_schedule); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3295 | q = rq->q; |
Jens Axboe | 94b5eb2 | 2011-04-12 10:12:19 +0200 | [diff] [blame] | 3296 | depth = 0; |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3297 | spin_lock(q->queue_lock); |
| 3298 | } |
Tejun Heo | 8ba6143 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 3299 | |
| 3300 | /* |
| 3301 | * Short-circuit if @q is dead |
| 3302 | */ |
Bart Van Assche | 3f3299d | 2012-11-28 13:42:38 +0100 | [diff] [blame] | 3303 | if (unlikely(blk_queue_dying(q))) { |
Tejun Heo | 8ba6143 | 2011-12-14 00:33:37 +0100 | [diff] [blame] | 3304 | __blk_end_request_all(rq, -ENODEV); |
| 3305 | continue; |
| 3306 | } |
| 3307 | |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3308 | /* |
| 3309 | * rq is already accounted, so use raw insert |
| 3310 | */ |
Jens Axboe | 401a18e | 2011-03-25 16:57:52 +0100 | [diff] [blame] | 3311 | if (rq->cmd_flags & (REQ_FLUSH | REQ_FUA)) |
| 3312 | __elv_add_request(q, rq, ELEVATOR_INSERT_FLUSH); |
| 3313 | else |
| 3314 | __elv_add_request(q, rq, ELEVATOR_INSERT_SORT_MERGE); |
Jens Axboe | 94b5eb2 | 2011-04-12 10:12:19 +0200 | [diff] [blame] | 3315 | |
| 3316 | depth++; |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3317 | } |
| 3318 | |
Jens Axboe | 99e2259 | 2011-04-18 09:59:55 +0200 | [diff] [blame] | 3319 | /* |
| 3320 | * This drops the queue lock |
| 3321 | */ |
| 3322 | if (q) |
Jens Axboe | 49cac01 | 2011-04-16 13:51:05 +0200 | [diff] [blame] | 3323 | queue_unplugged(q, depth, from_schedule); |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3324 | |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3325 | local_irq_restore(flags); |
| 3326 | } |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3327 | |
| 3328 | void blk_finish_plug(struct blk_plug *plug) |
| 3329 | { |
Shaohua Li | dd6cf3e | 2015-05-08 10:51:28 -0700 | [diff] [blame] | 3330 | if (plug != current->plug) |
| 3331 | return; |
Jens Axboe | f660378 | 2011-04-15 15:49:07 +0200 | [diff] [blame] | 3332 | blk_flush_plug_list(plug, false); |
Christoph Hellwig | 88b996c | 2011-04-15 15:20:10 +0200 | [diff] [blame] | 3333 | |
Shaohua Li | dd6cf3e | 2015-05-08 10:51:28 -0700 | [diff] [blame] | 3334 | current->plug = NULL; |
Jens Axboe | 73c1010 | 2011-03-08 13:19:51 +0100 | [diff] [blame] | 3335 | } |
| 3336 | EXPORT_SYMBOL(blk_finish_plug); |
| 3337 | |
Jens Axboe | 05229be | 2015-11-05 10:44:55 -0700 | [diff] [blame] | 3338 | bool blk_poll(struct request_queue *q, blk_qc_t cookie) |
| 3339 | { |
| 3340 | struct blk_plug *plug; |
| 3341 | long state; |
| 3342 | |
| 3343 | if (!q->mq_ops || !q->mq_ops->poll || !blk_qc_t_valid(cookie) || |
| 3344 | !test_bit(QUEUE_FLAG_POLL, &q->queue_flags)) |
| 3345 | return false; |
| 3346 | |
| 3347 | plug = current->plug; |
| 3348 | if (plug) |
| 3349 | blk_flush_plug_list(plug, false); |
| 3350 | |
| 3351 | state = current->state; |
| 3352 | while (!need_resched()) { |
| 3353 | unsigned int queue_num = blk_qc_t_to_queue_num(cookie); |
| 3354 | struct blk_mq_hw_ctx *hctx = q->queue_hw_ctx[queue_num]; |
| 3355 | int ret; |
| 3356 | |
| 3357 | hctx->poll_invoked++; |
| 3358 | |
| 3359 | ret = q->mq_ops->poll(hctx, blk_qc_t_to_tag(cookie)); |
| 3360 | if (ret > 0) { |
| 3361 | hctx->poll_success++; |
| 3362 | set_current_state(TASK_RUNNING); |
| 3363 | return true; |
| 3364 | } |
| 3365 | |
| 3366 | if (signal_pending_state(state, current)) |
| 3367 | set_current_state(TASK_RUNNING); |
| 3368 | |
| 3369 | if (current->state == TASK_RUNNING) |
| 3370 | return true; |
| 3371 | if (ret < 0) |
| 3372 | break; |
| 3373 | cpu_relax(); |
| 3374 | } |
| 3375 | |
| 3376 | return false; |
| 3377 | } |
| 3378 | |
Rafael J. Wysocki | 47fafbc | 2014-12-04 01:00:23 +0100 | [diff] [blame] | 3379 | #ifdef CONFIG_PM |
Lin Ming | 6c95466 | 2013-03-23 11:42:26 +0800 | [diff] [blame] | 3380 | /** |
| 3381 | * blk_pm_runtime_init - Block layer runtime PM initialization routine |
| 3382 | * @q: the queue of the device |
| 3383 | * @dev: the device the queue belongs to |
| 3384 | * |
| 3385 | * Description: |
| 3386 | * Initialize runtime-PM-related fields for @q and start auto suspend for |
| 3387 | * @dev. Drivers that want to take advantage of request-based runtime PM |
| 3388 | * should call this function after @dev has been initialized, and its |
| 3389 | * request queue @q has been allocated, and runtime PM for it can not happen |
| 3390 | * yet(either due to disabled/forbidden or its usage_count > 0). In most |
| 3391 | * cases, driver should call this function before any I/O has taken place. |
| 3392 | * |
| 3393 | * This function takes care of setting up using auto suspend for the device, |
| 3394 | * the autosuspend delay is set to -1 to make runtime suspend impossible |
| 3395 | * until an updated value is either set by user or by driver. Drivers do |
| 3396 | * not need to touch other autosuspend settings. |
| 3397 | * |
| 3398 | * The block layer runtime PM is request based, so only works for drivers |
| 3399 | * that use request as their IO unit instead of those directly use bio's. |
| 3400 | */ |
| 3401 | void blk_pm_runtime_init(struct request_queue *q, struct device *dev) |
| 3402 | { |
| 3403 | q->dev = dev; |
| 3404 | q->rpm_status = RPM_ACTIVE; |
| 3405 | pm_runtime_set_autosuspend_delay(q->dev, -1); |
| 3406 | pm_runtime_use_autosuspend(q->dev); |
| 3407 | } |
| 3408 | EXPORT_SYMBOL(blk_pm_runtime_init); |
| 3409 | |
| 3410 | /** |
| 3411 | * blk_pre_runtime_suspend - Pre runtime suspend check |
| 3412 | * @q: the queue of the device |
| 3413 | * |
| 3414 | * Description: |
| 3415 | * This function will check if runtime suspend is allowed for the device |
| 3416 | * by examining if there are any requests pending in the queue. If there |
| 3417 | * are requests pending, the device can not be runtime suspended; otherwise, |
| 3418 | * the queue's status will be updated to SUSPENDING and the driver can |
| 3419 | * proceed to suspend the device. |
| 3420 | * |
| 3421 | * For the not allowed case, we mark last busy for the device so that |
| 3422 | * runtime PM core will try to autosuspend it some time later. |
| 3423 | * |
| 3424 | * This function should be called near the start of the device's |
| 3425 | * runtime_suspend callback. |
| 3426 | * |
| 3427 | * Return: |
| 3428 | * 0 - OK to runtime suspend the device |
| 3429 | * -EBUSY - Device should not be runtime suspended |
| 3430 | */ |
| 3431 | int blk_pre_runtime_suspend(struct request_queue *q) |
| 3432 | { |
| 3433 | int ret = 0; |
| 3434 | |
Ken Xue | 4fd41a85 | 2015-12-01 14:45:46 +0800 | [diff] [blame] | 3435 | if (!q->dev) |
| 3436 | return ret; |
| 3437 | |
Lin Ming | 6c95466 | 2013-03-23 11:42:26 +0800 | [diff] [blame] | 3438 | spin_lock_irq(q->queue_lock); |
| 3439 | if (q->nr_pending) { |
| 3440 | ret = -EBUSY; |
| 3441 | pm_runtime_mark_last_busy(q->dev); |
| 3442 | } else { |
| 3443 | q->rpm_status = RPM_SUSPENDING; |
| 3444 | } |
| 3445 | spin_unlock_irq(q->queue_lock); |
| 3446 | return ret; |
| 3447 | } |
| 3448 | EXPORT_SYMBOL(blk_pre_runtime_suspend); |
| 3449 | |
| 3450 | /** |
| 3451 | * blk_post_runtime_suspend - Post runtime suspend processing |
| 3452 | * @q: the queue of the device |
| 3453 | * @err: return value of the device's runtime_suspend function |
| 3454 | * |
| 3455 | * Description: |
| 3456 | * Update the queue's runtime status according to the return value of the |
| 3457 | * device's runtime suspend function and mark last busy for the device so |
| 3458 | * that PM core will try to auto suspend the device at a later time. |
| 3459 | * |
| 3460 | * This function should be called near the end of the device's |
| 3461 | * runtime_suspend callback. |
| 3462 | */ |
| 3463 | void blk_post_runtime_suspend(struct request_queue *q, int err) |
| 3464 | { |
Ken Xue | 4fd41a85 | 2015-12-01 14:45:46 +0800 | [diff] [blame] | 3465 | if (!q->dev) |
| 3466 | return; |
| 3467 | |
Lin Ming | 6c95466 | 2013-03-23 11:42:26 +0800 | [diff] [blame] | 3468 | spin_lock_irq(q->queue_lock); |
| 3469 | if (!err) { |
| 3470 | q->rpm_status = RPM_SUSPENDED; |
| 3471 | } else { |
| 3472 | q->rpm_status = RPM_ACTIVE; |
| 3473 | pm_runtime_mark_last_busy(q->dev); |
| 3474 | } |
| 3475 | spin_unlock_irq(q->queue_lock); |
| 3476 | } |
| 3477 | EXPORT_SYMBOL(blk_post_runtime_suspend); |
| 3478 | |
| 3479 | /** |
| 3480 | * blk_pre_runtime_resume - Pre runtime resume processing |
| 3481 | * @q: the queue of the device |
| 3482 | * |
| 3483 | * Description: |
| 3484 | * Update the queue's runtime status to RESUMING in preparation for the |
| 3485 | * runtime resume of the device. |
| 3486 | * |
| 3487 | * This function should be called near the start of the device's |
| 3488 | * runtime_resume callback. |
| 3489 | */ |
| 3490 | void blk_pre_runtime_resume(struct request_queue *q) |
| 3491 | { |
Ken Xue | 4fd41a85 | 2015-12-01 14:45:46 +0800 | [diff] [blame] | 3492 | if (!q->dev) |
| 3493 | return; |
| 3494 | |
Lin Ming | 6c95466 | 2013-03-23 11:42:26 +0800 | [diff] [blame] | 3495 | spin_lock_irq(q->queue_lock); |
| 3496 | q->rpm_status = RPM_RESUMING; |
| 3497 | spin_unlock_irq(q->queue_lock); |
| 3498 | } |
| 3499 | EXPORT_SYMBOL(blk_pre_runtime_resume); |
| 3500 | |
| 3501 | /** |
| 3502 | * blk_post_runtime_resume - Post runtime resume processing |
| 3503 | * @q: the queue of the device |
| 3504 | * @err: return value of the device's runtime_resume function |
| 3505 | * |
| 3506 | * Description: |
| 3507 | * Update the queue's runtime status according to the return value of the |
| 3508 | * device's runtime_resume function. If it is successfully resumed, process |
| 3509 | * the requests that are queued into the device's queue when it is resuming |
| 3510 | * and then mark last busy and initiate autosuspend for it. |
| 3511 | * |
| 3512 | * This function should be called near the end of the device's |
| 3513 | * runtime_resume callback. |
| 3514 | */ |
| 3515 | void blk_post_runtime_resume(struct request_queue *q, int err) |
| 3516 | { |
Ken Xue | 4fd41a85 | 2015-12-01 14:45:46 +0800 | [diff] [blame] | 3517 | if (!q->dev) |
| 3518 | return; |
| 3519 | |
Lin Ming | 6c95466 | 2013-03-23 11:42:26 +0800 | [diff] [blame] | 3520 | spin_lock_irq(q->queue_lock); |
| 3521 | if (!err) { |
| 3522 | q->rpm_status = RPM_ACTIVE; |
| 3523 | __blk_run_queue(q); |
| 3524 | pm_runtime_mark_last_busy(q->dev); |
Aaron Lu | c60855c | 2013-05-17 15:47:20 +0800 | [diff] [blame] | 3525 | pm_request_autosuspend(q->dev); |
Lin Ming | 6c95466 | 2013-03-23 11:42:26 +0800 | [diff] [blame] | 3526 | } else { |
| 3527 | q->rpm_status = RPM_SUSPENDED; |
| 3528 | } |
| 3529 | spin_unlock_irq(q->queue_lock); |
| 3530 | } |
| 3531 | EXPORT_SYMBOL(blk_post_runtime_resume); |
| 3532 | #endif |
| 3533 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3534 | int __init blk_dev_init(void) |
| 3535 | { |
Nikanth Karthikesan | 9eb55b0 | 2009-04-27 14:53:54 +0200 | [diff] [blame] | 3536 | BUILD_BUG_ON(__REQ_NR_BITS > 8 * |
Maninder Singh | 0762b23 | 2015-07-07 12:41:07 +0530 | [diff] [blame] | 3537 | FIELD_SIZEOF(struct request, cmd_flags)); |
Nikanth Karthikesan | 9eb55b0 | 2009-04-27 14:53:54 +0200 | [diff] [blame] | 3538 | |
Tejun Heo | 89b90be | 2011-01-03 15:01:47 +0100 | [diff] [blame] | 3539 | /* used for unplugging and affects IO latency/throughput - HIGHPRI */ |
| 3540 | kblockd_workqueue = alloc_workqueue("kblockd", |
Matias Bjørling | 28747fc | 2014-06-11 23:43:54 +0200 | [diff] [blame] | 3541 | WQ_MEM_RECLAIM | WQ_HIGHPRI, 0); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3542 | if (!kblockd_workqueue) |
| 3543 | panic("Failed to create kblockd\n"); |
| 3544 | |
| 3545 | request_cachep = kmem_cache_create("blkdev_requests", |
Paul Mundt | 20c2df8 | 2007-07-20 10:11:58 +0900 | [diff] [blame] | 3546 | sizeof(struct request), 0, SLAB_PANIC, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3547 | |
Ilya Dryomov | c2789bd | 2015-11-20 22:16:46 +0100 | [diff] [blame] | 3548 | blk_requestq_cachep = kmem_cache_create("request_queue", |
Jens Axboe | 165125e | 2007-07-24 09:28:11 +0200 | [diff] [blame] | 3549 | sizeof(struct request_queue), 0, SLAB_PANIC, NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3550 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3551 | return 0; |
| 3552 | } |