With ordering requirements dropped, barrier and ordered are misnomers.
Now all block layer does is sequencing FLUSH and FUA. Rename them to
flush.
Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
---
block/blk-core.c | 21 +++++-----
block/blk-flush.c | 98 +++++++++++++++++++++++------------------------
block/blk.h | 4 +-
include/linux/blkdev.h | 26 ++++++------
4 files changed, 73 insertions(+), 76 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index 82bd6d9..efe391b 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -136,7 +136,7 @@ static void req_bio_endio(struct request *rq, struct bio *bio,
{
struct request_queue *q = rq->q;
- if (&q->bar_rq != rq) {
+ if (&q->flush_rq != rq) {
if (error)
clear_bit(BIO_UPTODATE, &bio->bi_flags);
else if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
@@ -160,13 +160,12 @@ static void req_bio_endio(struct request *rq, struct bio *bio,
if (bio->bi_size == 0)
bio_endio(bio, error);
} else {
-
/*
- * Okay, this is the barrier request in progress, just
- * record the error;
+ * Okay, this is the sequenced flush request in
+ * progress, just record the error;
*/
- if (error && !q->orderr)
- q->orderr = error;
+ if (error && !q->flush_err)
+ q->flush_err = error;
}
}
@@ -520,7 +519,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
init_timer(&q->unplug_timer);
setup_timer(&q->timeout, blk_rq_timed_out_timer, (unsigned long) q);
INIT_LIST_HEAD(&q->timeout_list);
- INIT_LIST_HEAD(&q->pending_barriers);
+ INIT_LIST_HEAD(&q->pending_flushes);
INIT_WORK(&q->unplug_work, blk_unplug_work);
kobject_init(&q->kobj, &blk_queue_ktype);
@@ -1758,11 +1757,11 @@ static void blk_account_io_completion(struct request *req, unsigned int bytes)
static void blk_account_io_done(struct request *req)
{
/*
- * Account IO completion. bar_rq isn't accounted as a normal
- * IO on queueing nor completion. Accounting the containing
- * request is enough.
+ * Account IO completion. flush_rq isn't accounted as a
+ * normal IO on queueing nor completion. Accounting the
+ * containing request is enough.
*/
- if (blk_do_io_stat(req) && req != &req->q->bar_rq) {
+ if (blk_do_io_stat(req) && req != &req->q->flush_rq) {
unsigned long duration = jiffies - req->start_time;
const int rw = rq_data_dir(req);
struct hd_struct *part;
diff --git a/block/blk-flush.c b/block/blk-flush.c
index e8b2e5c..dd87322 100644
--- a/block/blk-flush.c
+++ b/block/blk-flush.c
@@ -9,41 +9,38 @@
#include "blk.h"
-static struct request *queue_next_ordseq(struct request_queue *q);
+static struct request *queue_next_fseq(struct request_queue *q);
-/*
- * Cache flushing for ordered writes handling
- */
-unsigned blk_ordered_cur_seq(struct request_queue *q)
+unsigned blk_flush_cur_seq(struct request_queue *q)
{
- if (!q->ordseq)
+ if (!q->flush_seq)
return 0;
- return 1 << ffz(q->ordseq);
+ return 1 << ffz(q->flush_seq);
}
-static struct request *blk_ordered_complete_seq(struct request_queue *q,
- unsigned seq, int error)
+static struct request *blk_flush_complete_seq(struct request_queue *q,
+ unsigned seq, int error)
{
struct request *next_rq = NULL;
- if (error && !q->orderr)
- q->orderr = error;
+ if (error && !q->flush_err)
+ q->flush_err = error;
- BUG_ON(q->ordseq & seq);
- q->ordseq |= seq;
+ BUG_ON(q->flush_seq & seq);
+ q->flush_seq |= seq;
- if (blk_ordered_cur_seq(q) != QUEUE_ORDSEQ_DONE) {
- /* not complete yet, queue the next ordered sequence */
- next_rq = queue_next_ordseq(q);
+ if (blk_flush_cur_seq(q) != QUEUE_FSEQ_DONE) {
+ /* not complete yet, queue the next flush sequence */
+ next_rq = queue_next_fseq(q);
} else {
- /* complete this barrier request */
- __blk_end_request_all(q->orig_bar_rq, q->orderr);
- q->orig_bar_rq = NULL;
- q->ordseq = 0;
-
- /* dispatch the next barrier if there's one */
- if (!list_empty(&q->pending_barriers)) {
- next_rq = list_entry_rq(q->pending_barriers.next);
+ /* complete this flush request */
+ __blk_end_request_all(q->orig_flush_rq, q->flush_err);
+ q->orig_flush_rq = NULL;
+ q->flush_seq = 0;
+
+ /* dispatch the next flush if there's one */
+ if (!list_empty(&q->pending_flushes)) {
+ next_rq = list_entry_rq(q->pending_flushes.next);
list_move(&next_rq->queuelist, &q->queue_head);
}
}
@@ -53,19 +50,19 @@ static struct request *blk_ordered_complete_seq(struct request_queue *q,
static void pre_flush_end_io(struct request *rq, int error)
{
elv_completed_request(rq->q, rq);
- blk_ordered_complete_seq(rq->q, QUEUE_ORDSEQ_PREFLUSH, error);
+ blk_flush_complete_seq(rq->q, QUEUE_FSEQ_PREFLUSH, error);
}
-static void bar_end_io(struct request *rq, int error)
+static void flush_data_end_io(struct request *rq, int error)
{
elv_completed_request(rq->q, rq);
- blk_ordered_complete_seq(rq->q, QUEUE_ORDSEQ_BAR, error);
+ blk_flush_complete_seq(rq->q, QUEUE_FSEQ_DATA, error);
}
static void post_flush_end_io(struct request *rq, int error)
{
elv_completed_request(rq->q, rq);
- blk_ordered_complete_seq(rq->q, QUEUE_ORDSEQ_POSTFLUSH, error);
+ blk_flush_complete_seq(rq->q, QUEUE_FSEQ_POSTFLUSH, error);
}
static void queue_flush(struct request_queue *q, struct request *rq,
@@ -74,34 +71,34 @@ static void queue_flush(struct request_queue *q, struct request *rq,
blk_rq_init(q, rq);
rq->cmd_type = REQ_TYPE_FS;
rq->cmd_flags = REQ_FLUSH;
- rq->rq_disk = q->orig_bar_rq->rq_disk;
+ rq->rq_disk = q->orig_flush_rq->rq_disk;
rq->end_io = end_io;
elv_insert(q, rq, ELEVATOR_INSERT_FRONT);
}
-static struct request *queue_next_ordseq(struct request_queue *q)
+static struct request *queue_next_fseq(struct request_queue *q)
{
- struct request *rq = &q->bar_rq;
+ struct request *rq = &q->flush_rq;
- switch (blk_ordered_cur_seq(q)) {
- case QUEUE_ORDSEQ_PREFLUSH:
+ switch (blk_flush_cur_seq(q)) {
+ case QUEUE_FSEQ_PREFLUSH:
queue_flush(q, rq, pre_flush_end_io);
break;
- case QUEUE_ORDSEQ_BAR:
+ case QUEUE_FSEQ_DATA:
/* initialize proxy request and queue it */
blk_rq_init(q, rq);
- init_request_from_bio(rq, q->orig_bar_rq->bio);
+ init_request_from_bio(rq, q->orig_flush_rq->bio);
rq->cmd_flags &= ~REQ_HARDBARRIER;
if (q->ordered & QUEUE_ORDERED_DO_FUA)
rq->cmd_flags |= REQ_FUA;
- rq->end_io = bar_end_io;
+ rq->end_io = flush_data_end_io;
elv_insert(q, rq, ELEVATOR_INSERT_FRONT);
break;
- case QUEUE_ORDSEQ_POSTFLUSH:
+ case QUEUE_FSEQ_POSTFLUSH:
queue_flush(q, rq, post_flush_end_io);
break;
@@ -111,19 +108,20 @@ static struct request *queue_next_ordseq(struct request_queue *q)
return rq;
}
-struct request *blk_do_ordered(struct request_queue *q, struct request *rq)
+struct request *blk_do_flush(struct request_queue *q, struct request *rq)
{
unsigned skip = 0;
if (!(rq->cmd_flags & REQ_HARDBARRIER))
return rq;
- if (q->ordseq) {
+ if (q->flush_seq) {
/*
- * Barrier is already in progress and they can't be
- * processed in parallel. Queue for later processing.
+ * Sequenced flush is already in progress and they
+ * can't be processed in parallel. Queue for later
+ * processing.
*/
- list_move_tail(&rq->queuelist, &q->pending_barriers);
+ list_move_tail(&rq->queuelist, &q->pending_flushes);
return NULL;
}
@@ -138,11 +136,11 @@ struct request *blk_do_ordered(struct request_queue *q, struct request *rq)
}
/*
- * Start a new ordered sequence
+ * Start a new flush sequence
*/
- q->orderr = 0;
+ q->flush_err = 0;
q->ordered = q->next_ordered;
- q->ordseq |= QUEUE_ORDSEQ_STARTED;
+ q->flush_seq |= QUEUE_FSEQ_STARTED;
/*
* For an empty barrier, there's no actual BAR request, which
@@ -154,19 +152,19 @@ struct request *blk_do_ordered(struct request_queue *q, struct request *rq)
/* stash away the original request */
blk_dequeue_request(rq);
- q->orig_bar_rq = rq;
+ q->orig_flush_rq = rq;
if (!(q->ordered & QUEUE_ORDERED_DO_PREFLUSH))
- skip |= QUEUE_ORDSEQ_PREFLUSH;
+ skip |= QUEUE_FSEQ_PREFLUSH;
if (!(q->ordered & QUEUE_ORDERED_DO_BAR))
- skip |= QUEUE_ORDSEQ_BAR;
+ skip |= QUEUE_FSEQ_DATA;
if (!(q->ordered & QUEUE_ORDERED_DO_POSTFLUSH))
- skip |= QUEUE_ORDSEQ_POSTFLUSH;
+ skip |= QUEUE_FSEQ_POSTFLUSH;
/* complete skipped sequences and return the first sequence */
- return blk_ordered_complete_seq(q, skip, 0);
+ return blk_flush_complete_seq(q, skip, 0);
}
static void bio_end_empty_barrier(struct bio *bio, int err)
diff --git a/block/blk.h b/block/blk.h
index 08081e4..24b92bd 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -51,7 +51,7 @@ static inline void blk_clear_rq_complete(struct request *rq)
*/
#define ELV_ON_HASH(rq) (!hlist_unhashed(&(rq)->hash))
-struct request *blk_do_ordered(struct request_queue *q, struct request *rq);
+struct request *blk_do_flush(struct request_queue *q, struct request *rq);
static inline struct request *__elv_next_request(struct request_queue *q)
{
@@ -60,7 +60,7 @@ static inline struct request *__elv_next_request(struct request_queue *q)
while (1) {
while (!list_empty(&q->queue_head)) {
rq = list_entry_rq(q->queue_head.next);
- rq = blk_do_ordered(q, rq);
+ rq = blk_do_flush(q, rq);
if (rq)
return rq;
}
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 522ecda..87e58f0 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -357,13 +357,13 @@ struct request_queue
/*
* for flush operations
*/
+ unsigned int ordered, next_ordered;
unsigned int flush_flags;
-
- unsigned int ordered, next_ordered, ordseq;
- int orderr;
- struct request bar_rq;
- struct request *orig_bar_rq;
- struct list_head pending_barriers;
+ unsigned int flush_seq;
+ int flush_err;
+ struct request flush_rq;
+ struct request *orig_flush_rq;
+ struct list_head pending_flushes;
struct mutex sysfs_lock;
@@ -489,13 +489,13 @@ enum {
QUEUE_ORDERED_DO_FUA,
/*
- * Ordered operation sequence
+ * FLUSH/FUA sequences.
*/
- QUEUE_ORDSEQ_STARTED = (1 << 0), /* flushing in progress */
- QUEUE_ORDSEQ_PREFLUSH = (1 << 1), /* pre-flushing in progress */
- QUEUE_ORDSEQ_BAR = (1 << 2), /* barrier write in progress */
- QUEUE_ORDSEQ_POSTFLUSH = (1 << 3), /* post-flushing in progress */
- QUEUE_ORDSEQ_DONE = (1 << 4),
+ QUEUE_FSEQ_STARTED = (1 << 0), /* flushing in progress */
+ QUEUE_FSEQ_PREFLUSH = (1 << 1), /* pre-flushing in progress */
+ QUEUE_FSEQ_DATA = (1 << 2), /* data write in progress */
+ QUEUE_FSEQ_POSTFLUSH = (1 << 3), /* post-flushing in progress */
+ QUEUE_FSEQ_DONE = (1 << 4),
};
#define blk_queue_plugged(q) test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags)
@@ -507,7 +507,7 @@ enum {
#define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
#define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
#define blk_queue_add_random(q) test_bit(QUEUE_FLAG_ADD_RANDOM, &(q)->queue_flags)
-#define blk_queue_flushing(q) ((q)->ordseq)
+#define blk_queue_flushing(q) ((q)->flush_seq)
#define blk_queue_stackable(q) \
test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
#define blk_queue_discard(q) test_bit(QUEUE_FLAG_DISCARD, &(q)->queue_flags)
--
1.7.1
--
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