diff options
Diffstat (limited to 'Documentation/block/writeback_cache_control.txt')
| -rw-r--r-- | Documentation/block/writeback_cache_control.txt | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/Documentation/block/writeback_cache_control.txt b/Documentation/block/writeback_cache_control.txt index 83407d36630a..59e0516cbf6b 100644 --- a/Documentation/block/writeback_cache_control.txt +++ b/Documentation/block/writeback_cache_control.txt @@ -71,7 +71,7 @@ requests that have a payload. For devices with volatile write caches the driver needs to tell the block layer that it supports flushing caches by doing: - blk_queue_flush(sdkp->disk->queue, REQ_FLUSH); + blk_queue_write_cache(sdkp->disk->queue, true, false); and handle empty REQ_FLUSH requests in its prep_fn/request_fn. Note that REQ_FLUSH requests with a payload are automatically turned into a sequence @@ -79,7 +79,7 @@ of an empty REQ_FLUSH request followed by the actual write by the block layer. For devices that also support the FUA bit the block layer needs to be told to pass through the REQ_FUA bit using: - blk_queue_flush(sdkp->disk->queue, REQ_FLUSH | REQ_FUA); + blk_queue_write_cache(sdkp->disk->queue, true, true); and the driver must handle write requests that have the REQ_FUA bit set in prep_fn/request_fn. If the FUA bit is not natively supported the block |