[PATCH 1/6] block: reorganize QUEUE_ORDERED_* constants

From: Tejun Heo
Date: Thu Nov 27 2008 - 23:34:24 EST


Separate out ordering type (drain,) and action masks (preflush,
postflush, fua) from visible ordering mode selectors
(QUEUE_ORDERED_*). Ordering types are now named QUEUE_ORDERED_BY_*
while action masks are named QUEUE_ORDERED_DO_*.

This change is necessary to add QUEUE_ORDERED_DO_BAR and make it
optional to improve empty barrier implementation.

Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
---
block/blk-barrier.c | 20 ++++++++++----------
include/linux/blkdev.h | 39 +++++++++++++++++++++++----------------
2 files changed, 33 insertions(+), 26 deletions(-)

diff --git a/block/blk-barrier.c b/block/blk-barrier.c
index 6e72d66..1d7adc7 100644
--- a/block/blk-barrier.c
+++ b/block/blk-barrier.c
@@ -24,8 +24,8 @@
int blk_queue_ordered(struct request_queue *q, unsigned ordered,
prepare_flush_fn *prepare_flush_fn)
{
- if (ordered & (QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_POSTFLUSH) &&
- prepare_flush_fn == NULL) {
+ if (!prepare_flush_fn && (ordered & (QUEUE_ORDERED_DO_PREFLUSH |
+ QUEUE_ORDERED_DO_POSTFLUSH))) {
printk(KERN_ERR "%s: prepare_flush_fn required\n", __func__);
return -EINVAL;
}
@@ -134,7 +134,7 @@ static void queue_flush(struct request_queue *q, unsigned which)
struct request *rq;
rq_end_io_fn *end_io;

- if (which == QUEUE_ORDERED_PREFLUSH) {
+ if (which == QUEUE_ORDERED_DO_PREFLUSH) {
rq = &q->pre_flush_rq;
end_io = pre_flush_end_io;
} else {
@@ -167,7 +167,7 @@ static inline struct request *start_ordered(struct request_queue *q,
blk_rq_init(q, rq);
if (bio_data_dir(q->orig_bar_rq->bio) == WRITE)
rq->cmd_flags |= REQ_RW;
- if (q->ordered & QUEUE_ORDERED_FUA)
+ if (q->ordered & QUEUE_ORDERED_DO_FUA)
rq->cmd_flags |= REQ_FUA;
init_request_from_bio(rq, q->orig_bar_rq->bio);
rq->end_io = bar_end_io;
@@ -181,20 +181,20 @@ static inline struct request *start_ordered(struct request_queue *q,
* there will be no data written between the pre and post flush.
* Hence a single flush will suffice.
*/
- if ((q->ordered & QUEUE_ORDERED_POSTFLUSH) && !blk_empty_barrier(rq))
- queue_flush(q, QUEUE_ORDERED_POSTFLUSH);
+ if ((q->ordered & QUEUE_ORDERED_DO_POSTFLUSH) && !blk_empty_barrier(rq))
+ queue_flush(q, QUEUE_ORDERED_DO_POSTFLUSH);
else
q->ordseq |= QUEUE_ORDSEQ_POSTFLUSH;

elv_insert(q, rq, ELEVATOR_INSERT_FRONT);

- if (q->ordered & QUEUE_ORDERED_PREFLUSH) {
- queue_flush(q, QUEUE_ORDERED_PREFLUSH);
+ if (q->ordered & QUEUE_ORDERED_DO_PREFLUSH) {
+ queue_flush(q, QUEUE_ORDERED_DO_PREFLUSH);
rq = &q->pre_flush_rq;
} else
q->ordseq |= QUEUE_ORDSEQ_PREFLUSH;

- if ((q->ordered & QUEUE_ORDERED_TAG) || q->in_flight == 0)
+ if ((q->ordered & QUEUE_ORDERED_BY_TAG) || q->in_flight == 0)
q->ordseq |= QUEUE_ORDSEQ_DRAIN;
else
rq = NULL;
@@ -237,7 +237,7 @@ int blk_do_ordered(struct request_queue *q, struct request **rqp)
rq != &q->pre_flush_rq && rq != &q->post_flush_rq)
return 1;

- if (q->ordered & QUEUE_ORDERED_TAG) {
+ if (q->ordered & QUEUE_ORDERED_BY_TAG) {
/* Ordered by tag. Blocking the next barrier is enough. */
if (is_barrier && rq != &q->bar_rq)
*rqp = NULL;
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index bedeea2..7f9cd08 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -523,22 +523,29 @@ enum {
* TAG_FLUSH : ordering by tag w/ pre and post flushes
* TAG_FUA : ordering by tag w/ pre flush and FUA write
*/
- QUEUE_ORDERED_NONE = 0x00,
- QUEUE_ORDERED_DRAIN = 0x01,
- QUEUE_ORDERED_TAG = 0x02,
-
- QUEUE_ORDERED_PREFLUSH = 0x10,
- QUEUE_ORDERED_POSTFLUSH = 0x20,
- QUEUE_ORDERED_FUA = 0x40,
-
- QUEUE_ORDERED_DRAIN_FLUSH = QUEUE_ORDERED_DRAIN |
- QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_POSTFLUSH,
- QUEUE_ORDERED_DRAIN_FUA = QUEUE_ORDERED_DRAIN |
- QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_FUA,
- QUEUE_ORDERED_TAG_FLUSH = QUEUE_ORDERED_TAG |
- QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_POSTFLUSH,
- QUEUE_ORDERED_TAG_FUA = QUEUE_ORDERED_TAG |
- QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_FUA,
+ QUEUE_ORDERED_BY_DRAIN = 0x01,
+ QUEUE_ORDERED_BY_TAG = 0x02,
+ QUEUE_ORDERED_DO_PREFLUSH = 0x10,
+ QUEUE_ORDERED_DO_POSTFLUSH = 0x40,
+ QUEUE_ORDERED_DO_FUA = 0x80,
+
+ QUEUE_ORDERED_NONE = 0x00,
+
+ QUEUE_ORDERED_DRAIN = QUEUE_ORDERED_BY_DRAIN,
+ QUEUE_ORDERED_DRAIN_FLUSH = QUEUE_ORDERED_DRAIN |
+ QUEUE_ORDERED_DO_PREFLUSH |
+ QUEUE_ORDERED_DO_POSTFLUSH,
+ QUEUE_ORDERED_DRAIN_FUA = QUEUE_ORDERED_DRAIN |
+ QUEUE_ORDERED_DO_PREFLUSH |
+ QUEUE_ORDERED_DO_FUA,
+
+ QUEUE_ORDERED_TAG = QUEUE_ORDERED_BY_TAG,
+ QUEUE_ORDERED_TAG_FLUSH = QUEUE_ORDERED_TAG |
+ QUEUE_ORDERED_DO_PREFLUSH |
+ QUEUE_ORDERED_DO_POSTFLUSH,
+ QUEUE_ORDERED_TAG_FUA = QUEUE_ORDERED_TAG |
+ QUEUE_ORDERED_DO_PREFLUSH |
+ QUEUE_ORDERED_DO_FUA,

/*
* Ordered operation sequence
--
1.5.6

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