2 * Functions related to setting various queue properties from drivers
4 #include <linux/kernel.h>
5 #include <linux/module.h>
7 #include <linux/blkdev.h>
8 #include <linux/blk-mq.h>
9 #include <linux/sched/sysctl.h>
12 #include "blk-mq-sched.h"
15 * blk_end_sync_rq - executes a completion event on a request
16 * @rq: request to complete
17 * @error: end I/O status of the request
19 static void blk_end_sync_rq(struct request
*rq
, blk_status_t error
)
21 struct completion
*waiting
= rq
->end_io_data
;
23 rq
->end_io_data
= NULL
;
26 * complete last, if this is a stack request the process (and thus
27 * the rq pointer) could be invalid right after this complete()
33 * blk_execute_rq_nowait - insert a request into queue for execution
34 * @q: queue to insert the request in
35 * @bd_disk: matching gendisk
36 * @rq: request to insert
37 * @at_head: insert request at head or tail of queue
38 * @done: I/O completion handler
41 * Insert a fully prepared request at the back of the I/O scheduler queue
42 * for execution. Don't wait for completion.
45 * This function will invoke @done directly if the queue is dead.
47 void blk_execute_rq_nowait(struct request_queue
*q
, struct gendisk
*bd_disk
,
48 struct request
*rq
, int at_head
,
51 WARN_ON(irqs_disabled());
52 WARN_ON(!blk_rq_is_passthrough(rq
));
54 rq
->rq_disk
= bd_disk
;
58 * don't check dying flag for MQ because the request won't
59 * be reused after dying flag is set
61 blk_mq_sched_insert_request(rq
, at_head
, true, false);
63 EXPORT_SYMBOL_GPL(blk_execute_rq_nowait
);
66 * blk_execute_rq - insert a request into queue for execution
67 * @q: queue to insert the request in
68 * @bd_disk: matching gendisk
69 * @rq: request to insert
70 * @at_head: insert request at head or tail of queue
73 * Insert a fully prepared request at the back of the I/O scheduler queue
74 * for execution and wait for completion.
76 void blk_execute_rq(struct request_queue
*q
, struct gendisk
*bd_disk
,
77 struct request
*rq
, int at_head
)
79 DECLARE_COMPLETION_ONSTACK(wait
);
80 unsigned long hang_check
;
82 rq
->end_io_data
= &wait
;
83 blk_execute_rq_nowait(q
, bd_disk
, rq
, at_head
, blk_end_sync_rq
);
85 /* Prevent hang_check timer from firing at us during very long I/O */
86 hang_check
= sysctl_hung_task_timeout_secs
;
88 while (!wait_for_completion_io_timeout(&wait
, hang_check
* (HZ
/2)));
90 wait_for_completion_io(&wait
);
92 EXPORT_SYMBOL(blk_execute_rq
);