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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/block/blk-exec.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/block/blk-exec.c')
-rw-r--r-- | kernel/block/blk-exec.c | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/kernel/block/blk-exec.c b/kernel/block/blk-exec.c new file mode 100644 index 000000000..9924725fa --- /dev/null +++ b/kernel/block/blk-exec.c @@ -0,0 +1,143 @@ +/* + * 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" + +/* + * for max sense size + */ +#include <scsi/scsi_cmnd.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, int 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) +{ + int where = at_head ? ELEVATOR_INSERT_FRONT : ELEVATOR_INSERT_BACK; + bool is_pm_resume; + + WARN_ON(irqs_disabled()); + WARN_ON(rq->cmd_type == REQ_TYPE_FS); + + rq->rq_disk = bd_disk; + rq->end_io = done; + + /* + * don't check dying flag for MQ because the request won't + * be resued after dying flag is set + */ + if (q->mq_ops) { + blk_mq_insert_request(rq, at_head, true, false); + return; + } + + /* + * need to check this before __blk_run_queue(), because rq can + * be freed before that returns. + */ + is_pm_resume = rq->cmd_type == REQ_TYPE_PM_RESUME; + + spin_lock_irq(q->queue_lock); + + if (unlikely(blk_queue_dying(q))) { + rq->cmd_flags |= REQ_QUIET; + rq->errors = -ENXIO; + __blk_end_request_all(rq, rq->errors); + spin_unlock_irq(q->queue_lock); + return; + } + + __elv_add_request(q, rq, where); + __blk_run_queue(q); + /* the queue is stopped so it won't be run */ + if (is_pm_resume) + __blk_run_queue_uncond(q); + spin_unlock_irq(q->queue_lock); +} +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. + */ +int blk_execute_rq(struct request_queue *q, struct gendisk *bd_disk, + struct request *rq, int at_head) +{ + DECLARE_COMPLETION_ONSTACK(wait); + char sense[SCSI_SENSE_BUFFERSIZE]; + int err = 0; + unsigned long hang_check; + + if (!rq->sense) { + memset(sense, 0, sizeof(sense)); + rq->sense = sense; + rq->sense_len = 0; + } + + 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); + + if (rq->errors) + err = -EIO; + + if (rq->sense == sense) { + rq->sense = NULL; + rq->sense_len = 0; + } + + return err; +} +EXPORT_SYMBOL(blk_execute_rq); |