diff options
Diffstat (limited to 'block/blk-exec.c')
-rw-r--r-- | block/blk-exec.c | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/block/blk-exec.c b/block/blk-exec.c new file mode 100644 index 000000000..85324d53d --- /dev/null +++ b/block/blk-exec.c @@ -0,0 +1,95 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Functions related to setting various queue properties from drivers + */ +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/bio.h> +#include <linux/blkdev.h> +#include <linux/blk-mq.h> +#include <linux/sched/sysctl.h> + +#include "blk.h" +#include "blk-mq-sched.h" + +/** + * blk_end_sync_rq - executes a completion event on a request + * @rq: request to complete + * @error: end I/O status of the request + */ +static void blk_end_sync_rq(struct request *rq, blk_status_t error) +{ + struct completion *waiting = rq->end_io_data; + + rq->end_io_data = NULL; + + /* + * complete last, if this is a stack request the process (and thus + * the rq pointer) could be invalid right after this complete() + */ + complete(waiting); +} + +/** + * blk_execute_rq_nowait - insert a request into queue for execution + * @q: queue to insert the request in + * @bd_disk: matching gendisk + * @rq: request to insert + * @at_head: insert request at head or tail of queue + * @done: I/O completion handler + * + * Description: + * Insert a fully prepared request at the back of the I/O scheduler queue + * for execution. Don't wait for completion. + * + * Note: + * This function will invoke @done directly if the queue is dead. + */ +void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, + struct request *rq, int at_head, + rq_end_io_fn *done) +{ + WARN_ON(irqs_disabled()); + WARN_ON(!blk_rq_is_passthrough(rq)); + + rq->rq_disk = bd_disk; + rq->end_io = done; + + blk_account_io_start(rq); + + /* + * don't check dying flag for MQ because the request won't + * be reused after dying flag is set + */ + blk_mq_sched_insert_request(rq, at_head, true, false); +} +EXPORT_SYMBOL_GPL(blk_execute_rq_nowait); + +/** + * blk_execute_rq - insert a request into queue for execution + * @q: queue to insert the request in + * @bd_disk: matching gendisk + * @rq: request to insert + * @at_head: insert request at head or tail of queue + * + * Description: + * Insert a fully prepared request at the back of the I/O scheduler queue + * for execution and wait for completion. + */ +void blk_execute_rq(struct request_queue *q, struct gendisk *bd_disk, + struct request *rq, int at_head) +{ + DECLARE_COMPLETION_ONSTACK(wait); + unsigned long hang_check; + + rq->end_io_data = &wait; + blk_execute_rq_nowait(q, bd_disk, rq, at_head, blk_end_sync_rq); + + /* Prevent hang_check timer from firing at us during very long I/O */ + hang_check = sysctl_hung_task_timeout_secs; + if (hang_check) + while (!wait_for_completion_io_timeout(&wait, hang_check * (HZ/2))); + else + wait_for_completion_io(&wait); +} +EXPORT_SYMBOL(blk_execute_rq); |