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-rw-r--r--Documentation/block/barrier.txt16
1 files changed, 3 insertions, 13 deletions
diff --git a/Documentation/block/barrier.txt b/Documentation/block/barrier.txt
index a272c3db8094..7d279f2f5bb2 100644
--- a/Documentation/block/barrier.txt
+++ b/Documentation/block/barrier.txt
@@ -82,23 +82,12 @@ including draining and flushing.
typedef void (prepare_flush_fn)(request_queue_t *q, struct request *rq);
int blk_queue_ordered(request_queue_t *q, unsigned ordered,
- prepare_flush_fn *prepare_flush_fn,
- unsigned gfp_mask);
-
-int blk_queue_ordered_locked(request_queue_t *q, unsigned ordered,
- prepare_flush_fn *prepare_flush_fn,
- unsigned gfp_mask);
-
-The only difference between the two functions is whether or not the
-caller is holding q->queue_lock on entry. The latter expects the
-caller is holding the lock.
+ prepare_flush_fn *prepare_flush_fn);
@q : the queue in question
@ordered : the ordered mode the driver/device supports
@prepare_flush_fn : this function should prepare @rq such that it
flushes cache to physical medium when executed
-@gfp_mask : gfp_mask used when allocating data structures
- for ordered processing
For example, SCSI disk driver's prepare_flush_fn looks like the
following.
@@ -106,9 +95,10 @@ following.
static void sd_prepare_flush(request_queue_t *q, struct request *rq)
{
memset(rq->cmd, 0, sizeof(rq->cmd));
- rq->flags |= REQ_BLOCK_PC;
+ rq->cmd_type = REQ_TYPE_BLOCK_PC;
rq->timeout = SD_TIMEOUT;
rq->cmd[0] = SYNCHRONIZE_CACHE;
+ rq->cmd_len = 10;
}
The following seven ordered modes are supported. The following table
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