Commit | Line | Data |
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86db1e29 JA |
1 | /* |
2 | * Functions related to setting various queue properties from drivers | |
3 | */ | |
4 | #include <linux/kernel.h> | |
5 | #include <linux/module.h> | |
6 | #include <linux/bio.h> | |
7 | #include <linux/blkdev.h> | |
320ae51f | 8 | #include <linux/blk-mq.h> |
cf4aebc2 | 9 | #include <linux/sched/sysctl.h> |
86db1e29 JA |
10 | |
11 | #include "blk.h" | |
12 | ||
13 | /* | |
14 | * for max sense size | |
15 | */ | |
16 | #include <scsi/scsi_cmnd.h> | |
17 | ||
18 | /** | |
19 | * blk_end_sync_rq - executes a completion event on a request | |
20 | * @rq: request to complete | |
710027a4 | 21 | * @error: end I/O status of the request |
86db1e29 | 22 | */ |
681a561b | 23 | static void blk_end_sync_rq(struct request *rq, int error) |
86db1e29 JA |
24 | { |
25 | struct completion *waiting = rq->end_io_data; | |
26 | ||
27 | rq->end_io_data = NULL; | |
86db1e29 JA |
28 | |
29 | /* | |
30 | * complete last, if this is a stack request the process (and thus | |
31 | * the rq pointer) could be invalid right after this complete() | |
32 | */ | |
33 | complete(waiting); | |
34 | } | |
86db1e29 JA |
35 | |
36 | /** | |
37 | * blk_execute_rq_nowait - insert a request into queue for execution | |
38 | * @q: queue to insert the request in | |
39 | * @bd_disk: matching gendisk | |
40 | * @rq: request to insert | |
41 | * @at_head: insert request at head or tail of queue | |
42 | * @done: I/O completion handler | |
43 | * | |
44 | * Description: | |
710027a4 | 45 | * Insert a fully prepared request at the back of the I/O scheduler queue |
86db1e29 | 46 | * for execution. Don't wait for completion. |
e81ca6fe MR |
47 | * |
48 | * Note: | |
49 | * This function will invoke @done directly if the queue is dead. | |
86db1e29 JA |
50 | */ |
51 | void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, | |
52 | struct request *rq, int at_head, | |
53 | rq_end_io_fn *done) | |
54 | { | |
55 | int where = at_head ? ELEVATOR_INSERT_FRONT : ELEVATOR_INSERT_BACK; | |
893d290f | 56 | bool is_pm_resume; |
86db1e29 | 57 | |
8ba61435 | 58 | WARN_ON(irqs_disabled()); |
e81ca6fe MR |
59 | |
60 | rq->rq_disk = bd_disk; | |
61 | rq->end_io = done; | |
320ae51f | 62 | |
43a5e4e2 ML |
63 | /* |
64 | * don't check dying flag for MQ because the request won't | |
65 | * be resued after dying flag is set | |
66 | */ | |
320ae51f | 67 | if (q->mq_ops) { |
feb71dae | 68 | blk_mq_insert_request(rq, at_head, true, false); |
320ae51f JA |
69 | return; |
70 | } | |
71 | ||
893d290f RD |
72 | /* |
73 | * need to check this before __blk_run_queue(), because rq can | |
74 | * be freed before that returns. | |
75 | */ | |
76 | is_pm_resume = rq->cmd_type == REQ_TYPE_PM_RESUME; | |
e81ca6fe | 77 | |
8ba61435 TH |
78 | spin_lock_irq(q->queue_lock); |
79 | ||
3f3299d5 | 80 | if (unlikely(blk_queue_dying(q))) { |
7652113c | 81 | rq->cmd_flags |= REQ_QUIET; |
bfe159a5 | 82 | rq->errors = -ENXIO; |
7652113c | 83 | __blk_end_request_all(rq, rq->errors); |
e81ca6fe | 84 | spin_unlock_irq(q->queue_lock); |
bfe159a5 JB |
85 | return; |
86 | } | |
87 | ||
7eaceacc | 88 | __elv_add_request(q, rq, where); |
24ecfbe2 | 89 | __blk_run_queue(q); |
addd0a09 | 90 | /* the queue is stopped so it won't be run */ |
893d290f | 91 | if (is_pm_resume) |
c246e80d | 92 | __blk_run_queue_uncond(q); |
86db1e29 JA |
93 | spin_unlock_irq(q->queue_lock); |
94 | } | |
95 | EXPORT_SYMBOL_GPL(blk_execute_rq_nowait); | |
96 | ||
97 | /** | |
98 | * blk_execute_rq - insert a request into queue for execution | |
99 | * @q: queue to insert the request in | |
100 | * @bd_disk: matching gendisk | |
101 | * @rq: request to insert | |
102 | * @at_head: insert request at head or tail of queue | |
103 | * | |
104 | * Description: | |
710027a4 | 105 | * Insert a fully prepared request at the back of the I/O scheduler queue |
86db1e29 JA |
106 | * for execution and wait for completion. |
107 | */ | |
108 | int blk_execute_rq(struct request_queue *q, struct gendisk *bd_disk, | |
109 | struct request *rq, int at_head) | |
110 | { | |
111 | DECLARE_COMPLETION_ONSTACK(wait); | |
112 | char sense[SCSI_SENSE_BUFFERSIZE]; | |
113 | int err = 0; | |
4b197769 | 114 | unsigned long hang_check; |
86db1e29 | 115 | |
86db1e29 JA |
116 | if (!rq->sense) { |
117 | memset(sense, 0, sizeof(sense)); | |
118 | rq->sense = sense; | |
119 | rq->sense_len = 0; | |
120 | } | |
121 | ||
122 | rq->end_io_data = &wait; | |
123 | blk_execute_rq_nowait(q, bd_disk, rq, at_head, blk_end_sync_rq); | |
4b197769 ML |
124 | |
125 | /* Prevent hang_check timer from firing at us during very long I/O */ | |
126 | hang_check = sysctl_hung_task_timeout_secs; | |
127 | if (hang_check) | |
5577022f | 128 | while (!wait_for_completion_io_timeout(&wait, hang_check * (HZ/2))); |
4b197769 | 129 | else |
5577022f | 130 | wait_for_completion_io(&wait); |
86db1e29 JA |
131 | |
132 | if (rq->errors) | |
133 | err = -EIO; | |
134 | ||
135 | return err; | |
136 | } | |
86db1e29 | 137 | EXPORT_SYMBOL(blk_execute_rq); |