[PATCH v2 1/4] block: Convert RQF_PREEMPT into REQ_PREEMPT

Bart Van Assche
2017-09-21T21:22:52Z

This patch does not change any functionality but makes the
REQ_PREEMPT flag available to blk_get_request(). A later patch
will add code to blk_get_request() that checks the REQ_PREEMPT
flag. Note: the IDE sense_rq request is allocated statically so
there is no blk_get_request() call that corresponds to this
request.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
---
block/blk-mq-debugfs.c | 2 +-
drivers/ide/ide-atapi.c | 3 +--
drivers/ide/ide-io.c | 2 +-
drivers/ide/ide-pm.c | 4 ++--
drivers/scsi/scsi_lib.c | 11 ++++++-----
include/linux/blk_types.h | 6 ++++++
include/linux/blkdev.h | 3 ---
7 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
index 980e73095643..62ac248a4984 100644
--- a/block/blk-mq-debugfs.c
+++ b/block/blk-mq-debugfs.c
@@ -266,6 +266,7 @@ static const char *const cmd_flag_name[] = {
CMD_FLAG_NAME(BACKGROUND),
CMD_FLAG_NAME(NOUNMAP),
CMD_FLAG_NAME(NOWAIT),
+ CMD_FLAG_NAME(PREEMPT),
};
#undef CMD_FLAG_NAME

@@ -279,7 +280,6 @@ static const char *const rqf_name[] = {
RQF_NAME(MIXED_MERGE),
RQF_NAME(MQ_INFLIGHT),
RQF_NAME(DONTPREP),
- RQF_NAME(PREEMPT),
RQF_NAME(COPY_USER),
RQF_NAME(FAILED),
RQF_NAME(QUIET),
diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c
index 14d1e7d9a1d6..1258739d5fa1 100644
--- a/drivers/ide/ide-atapi.c
+++ b/drivers/ide/ide-atapi.c
@@ -211,9 +211,8 @@ void ide_prep_sense(ide_drive_t *drive, struct request *rq)
}

sense_rq->rq_disk = rq->rq_disk;
- sense_rq->cmd_flags = REQ_OP_DRV_IN;
+ sense_rq->cmd_flags = REQ_OP_DRV_IN | REQ_PREEMPT;
ide_req(sense_rq)->type = ATA_PRIV_SENSE;
- sense_rq->rq_flags |= RQF_PREEMPT;

req->cmd[0] = GPCMD_REQUEST_SENSE;
req->cmd[4] = cmd_len;
diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c
index 3a234701d92c..06ffccd0fb10 100644
--- a/drivers/ide/ide-io.c
+++ b/drivers/ide/ide-io.c
@@ -539,7 +539,7 @@ void do_ide_request(struct request_queue *q)
*/
if ((drive->dev_flags & IDE_DFLAG_BLOCKED) &&
ata_pm_request(rq) == 0 &&
- (rq->rq_flags & RQF_PREEMPT) == 0) {
+ (rq->cmd_flags & REQ_PREEMPT) == 0) {
/* there should be no pending command at this point */
ide_unlock_port(hwif);
goto plug_device;
diff --git a/drivers/ide/ide-pm.c b/drivers/ide/ide-pm.c
index 544f02d673ca..f8d2709dcd56 100644
--- a/drivers/ide/ide-pm.c
+++ b/drivers/ide/ide-pm.c
@@ -89,9 +89,9 @@ int generic_ide_resume(struct device *dev)
}

memset(&rqpm, 0, sizeof(rqpm));
- rq = blk_get_request(drive->queue, REQ_OP_DRV_IN, __GFP_RECLAIM);
+ rq = blk_get_request(drive->queue, REQ_OP_DRV_IN | REQ_PREEMPT,
+ __GFP_RECLAIM);
ide_req(rq)->type = ATA_PRIV_PM_RESUME;
- rq->rq_flags |= RQF_PREEMPT;
rq->special = &rqpm;
rqpm.pm_step = IDE_PM_START_RESUME;
rqpm.pm_state = PM_EVENT_ON;
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index f6097b89d5d3..6db8247577a0 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -245,8 +245,9 @@ int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
int ret = DRIVER_ERROR << 24;

req = blk_get_request(sdev->request_queue,
- data_direction == DMA_TO_DEVICE ?
- REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, __GFP_RECLAIM);
+ (data_direction == DMA_TO_DEVICE ?
+ REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN) | REQ_PREEMPT,
+ __GFP_RECLAIM);
if (IS_ERR(req))
return ret;
rq = scsi_req(req);
@@ -260,7 +261,7 @@ int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
rq->retries = retries;
req->timeout = timeout;
req->cmd_flags |= flags;
- req->rq_flags |= rq_flags | RQF_QUIET | RQF_PREEMPT;
+ req->rq_flags |= rq_flags | RQF_QUIET;

/*
* head injection *required* here otherwise quiesce won't work
@@ -1271,7 +1272,7 @@ scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
/*
* If the devices is blocked we defer normal commands.
*/
- if (!(req->rq_flags & RQF_PREEMPT))
+ if (!(req->cmd_flags & REQ_PREEMPT))
ret = BLKPREP_DEFER;
break;
default:
@@ -1280,7 +1281,7 @@ scsi_prep_state_check(struct scsi_device *sdev, struct request *req)
* special commands. In particular any user initiated
* command is not allowed.
*/
- if (!(req->rq_flags & RQF_PREEMPT))
+ if (!(req->cmd_flags & REQ_PREEMPT))
ret = BLKPREP_KILL;
break;
}
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index a2d2aa709cef..b6b6bf44e462 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -229,6 +229,11 @@ enum req_flag_bits {
__REQ_NOUNMAP, /* do not free blocks when zeroing */

__REQ_NOWAIT, /* Don't wait if request will block */
+ /*
+ * set for "ide_preempt" requests and also for requests for which the
+ * SCSI "quiesce" state must be ignored.
+ */
+ __REQ_PREEMPT,
__REQ_NR_BITS, /* stops here */
};

@@ -248,6 +253,7 @@ enum req_flag_bits {

#define REQ_NOUNMAP (1ULL << __REQ_NOUNMAP)
#define REQ_NOWAIT (1ULL << __REQ_NOWAIT)
+#define REQ_PREEMPT (1ULL << __REQ_PREEMPT)

#define REQ_FAILFAST_MASK \
(REQ_FAILFAST_DEV | REQ_FAILFAST_TRANSPORT | REQ_FAILFAST_DRIVER)
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 460294bb0fa5..cd26901a6e25 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -96,9 +96,6 @@ typedef __u32 __bitwise req_flags_t;
#define RQF_MQ_INFLIGHT ((__force req_flags_t)(1 << 6))
/* don't call prep for this one */
#define RQF_DONTPREP ((__force req_flags_t)(1 << 7))
-/* set for "ide_preempt" requests and also for requests for which the SCSI
- "quiesce" state must be ignored. */
-#define RQF_PREEMPT ((__force req_flags_t)(1 << 8))
/* contains copies of user pages */
#define RQF_COPY_USER ((__force req_flags_t)(1 << 9))
/* vaguely specified driver internal error. Ignored by the block layer */
--
2.14.1