return next_rq;
}
+static void blk_flush_complete_seq_end_io(struct request_queue *q,
+ unsigned seq, int error)
+{
+ bool was_empty = elv_queue_empty(q);
+ struct request *next_rq;
+
+ next_rq = blk_flush_complete_seq(q, seq, error);
+
+ /*
+ * Moving a request silently to empty queue_head may stall the
+ * queue. Kick the queue in those cases. This function is called
+ * from request completion path and calling directly into
+ * request_fn may confuse the driver. Always use kblockd.
+ */
+ if (was_empty && next_rq)
+ __blk_run_queue(q, true);
+}
+
static void pre_flush_end_io(struct request *rq, int error)
{
elv_completed_request(rq->q, rq);
- blk_flush_complete_seq(rq->q, QUEUE_FSEQ_PREFLUSH, error);
+ blk_flush_complete_seq_end_io(rq->q, QUEUE_FSEQ_PREFLUSH, error);
}
static void flush_data_end_io(struct request *rq, int error)
{
elv_completed_request(rq->q, rq);
- blk_flush_complete_seq(rq->q, QUEUE_FSEQ_DATA, error);
+ blk_flush_complete_seq_end_io(rq->q, QUEUE_FSEQ_DATA, error);
}
static void post_flush_end_io(struct request *rq, int error)
{
elv_completed_request(rq->q, rq);
- blk_flush_complete_seq(rq->q, QUEUE_FSEQ_POSTFLUSH, error);
+ blk_flush_complete_seq_end_io(rq->q, QUEUE_FSEQ_POSTFLUSH, error);
}
-static void queue_flush(struct request_queue *q, struct request *rq,
- rq_end_io_fn *end_io)
+static void init_flush_request(struct request *rq, struct gendisk *disk)
{
- blk_rq_init(q, rq);
rq->cmd_type = REQ_TYPE_FS;
- rq->cmd_flags = REQ_FLUSH;
- rq->rq_disk = q->orig_flush_rq->rq_disk;
- rq->end_io = end_io;
-
- elv_insert(q, rq, ELEVATOR_INSERT_FRONT);
+ rq->cmd_flags = WRITE_FLUSH;
+ rq->rq_disk = disk;
}
static struct request *queue_next_fseq(struct request_queue *q)
struct request *orig_rq = q->orig_flush_rq;
struct request *rq = &q->flush_rq;
+ blk_rq_init(q, rq);
+
switch (blk_flush_cur_seq(q)) {
case QUEUE_FSEQ_PREFLUSH:
- queue_flush(q, rq, pre_flush_end_io);
+ init_flush_request(rq, orig_rq->rq_disk);
+ rq->end_io = pre_flush_end_io;
break;
-
case QUEUE_FSEQ_DATA:
- /* initialize proxy request, inherit FLUSH/FUA and queue it */
- blk_rq_init(q, rq);
init_request_from_bio(rq, orig_rq->bio);
+ /*
+ * orig_rq->rq_disk may be different from
+ * bio->bi_bdev->bd_disk if orig_rq got here through
+ * remapping drivers. Make sure rq->rq_disk points
+ * to the same one as orig_rq.
+ */
+ rq->rq_disk = orig_rq->rq_disk;
rq->cmd_flags &= ~(REQ_FLUSH | REQ_FUA);
rq->cmd_flags |= orig_rq->cmd_flags & (REQ_FLUSH | REQ_FUA);
rq->end_io = flush_data_end_io;
-
- elv_insert(q, rq, ELEVATOR_INSERT_FRONT);
break;
-
case QUEUE_FSEQ_POSTFLUSH:
- queue_flush(q, rq, post_flush_end_io);
+ init_flush_request(rq, orig_rq->rq_disk);
+ rq->end_io = post_flush_end_io;
break;
-
default:
BUG();
}
+
+ elv_insert(q, rq, ELEVATOR_INSERT_REQUEUE);
return rq;
}
return blk_flush_complete_seq(q, skip, 0);
}
-static void bio_end_empty_barrier(struct bio *bio, int err)
+static void bio_end_flush(struct bio *bio, int err)
{
- if (err) {
- if (err == -EOPNOTSUPP)
- set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
+ if (err)
clear_bit(BIO_UPTODATE, &bio->bi_flags);
- }
if (bio->bi_private)
complete(bio->bi_private);
bio_put(bio);
* @bdev: blockdev to issue flush for
* @gfp_mask: memory allocation flags (for bio_alloc)
* @error_sector: error sector
- * @flags: BLKDEV_IFL_* flags to control behaviour
*
* Description:
* Issue a flush for the block device in question. Caller can supply
* request was pushed in some internal queue for later handling.
*/
int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask,
- sector_t *error_sector, unsigned long flags)
+ sector_t *error_sector)
{
DECLARE_COMPLETION_ONSTACK(wait);
struct request_queue *q;
* some block devices may not have their queue correctly set up here
* (e.g. loop device without a backing file) and so issuing a flush
* here will panic. Ensure there is a request function before issuing
- * the barrier.
+ * the flush.
*/
if (!q->make_request_fn)
return -ENXIO;
bio = bio_alloc(gfp_mask, 0);
- bio->bi_end_io = bio_end_empty_barrier;
+ bio->bi_end_io = bio_end_flush;
bio->bi_bdev = bdev;
- if (test_bit(BLKDEV_WAIT, &flags))
- bio->bi_private = &wait;
+ bio->bi_private = &wait;
bio_get(bio);
- submit_bio(WRITE_BARRIER, bio);
- if (test_bit(BLKDEV_WAIT, &flags)) {
- wait_for_completion(&wait);
- /*
- * The driver must store the error location in ->bi_sector, if
- * it supports it. For non-stacked drivers, this should be
- * copied from blk_rq_pos(rq).
- */
- if (error_sector)
- *error_sector = bio->bi_sector;
- }
+ submit_bio(WRITE_FLUSH, bio);
+ wait_for_completion(&wait);
+
+ /*
+ * The driver must store the error location in ->bi_sector, if
+ * it supports it. For non-stacked drivers, this should be
+ * copied from blk_rq_pos(rq).
+ */
+ if (error_sector)
+ *error_sector = bio->bi_sector;
- if (bio_flagged(bio, BIO_EOPNOTSUPP))
- ret = -EOPNOTSUPP;
- else if (!bio_flagged(bio, BIO_UPTODATE))
+ if (!bio_flagged(bio, BIO_UPTODATE))
ret = -EIO;
bio_put(bio);
projects / linux-flexiantxendom0-natty.git / blobdiff