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authorChristoph Hellwig <hch@lst.de>2017-04-05 19:21:23 +0200
committerJens Axboe <axboe@fb.com>2017-04-08 11:25:38 -0600
commit48920ff2a5a940cd07d12cc79e4a2c75f1185aee (patch)
tree0505a85fce20a0d34c5d4bbc71ba8771a037e209 /Documentation
parent45c21793a6601b29926d67f7a07fe4077a45072e (diff)
block: remove the discard_zeroes_data flag
Now that we use the proper REQ_OP_WRITE_ZEROES operation everywhere we can kill this hack. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/ABI/testing/sysfs-block10
-rw-r--r--Documentation/block/queue-sysfs.txt5
2 files changed, 2 insertions, 13 deletions
diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block
index 2da04ce6aeef..dea212db9df3 100644
--- a/Documentation/ABI/testing/sysfs-block
+++ b/Documentation/ABI/testing/sysfs-block
@@ -213,14 +213,8 @@ What: /sys/block/<disk>/queue/discard_zeroes_data
Date: May 2011
Contact: Martin K. Petersen <martin.petersen@oracle.com>
Description:
- Devices that support discard functionality may return
- stale or random data when a previously discarded block
- is read back. This can cause problems if the filesystem
- expects discarded blocks to be explicitly cleared. If a
- device reports that it deterministically returns zeroes
- when a discarded area is read the discard_zeroes_data
- parameter will be set to one. Otherwise it will be 0 and
- the result of reading a discarded area is undefined.
+ Will always return 0. Don't rely on any specific behavior
+ for discards, and don't read this file.
What: /sys/block/<disk>/queue/write_same_max_bytes
Date: January 2012
diff --git a/Documentation/block/queue-sysfs.txt b/Documentation/block/queue-sysfs.txt
index b7f6bdc96d73..2c1e67058fd3 100644
--- a/Documentation/block/queue-sysfs.txt
+++ b/Documentation/block/queue-sysfs.txt
@@ -43,11 +43,6 @@ large discards are issued, setting this value lower will make Linux issue
smaller discards and potentially help reduce latencies induced by large
discard operations.
-discard_zeroes_data (RO)
-------------------------
-When read, this file will show if the discarded block are zeroed by the
-device or not. If its value is '1' the blocks are zeroed otherwise not.
-
hw_sector_size (RO)
-------------------
This is the hardware sector size of the device, in bytes.