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| author | Christoph Hellwig <hch@lst.de> | 2023-07-07 12:42:39 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-09-13 10:42:40 +0300 |
| commit | 00c0b2825bb5df26c339cef1d32db6a8755de203 (patch) | |
| tree | 21140bad2e5750ca402982dcf665ee6e74a4bc67 /include | |
| parent | e5e0ec8ff16089a0801cd6a1748003697b6b901f (diff) | |
| download | linux-00c0b2825bb5df26c339cef1d32db6a8755de203.tar.xz | |
block: don't allow enabling a cache on devices that don't support it
[ Upstream commit 43c9835b144c7ce29efe142d662529662a9eb376 ]
Currently the write_cache attribute allows enabling the QUEUE_FLAG_WC
flag on devices that never claimed the capability.
Fix that by adding a QUEUE_FLAG_HW_WC flag that is set by
blk_queue_write_cache and guards re-enabling the cache through sysfs.
Note that any rescan that calls blk_queue_write_cache will still
re-enable the write cache as in the current code.
Fixes: 93e9d8e836cb ("block: add ability to flag write back caching on a device")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230707094239.107968-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/blkdev.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 427e79ac7219..57674b3c5877 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -565,6 +565,7 @@ struct request_queue { #define QUEUE_FLAG_NOXMERGES 9 /* No extended merges */ #define QUEUE_FLAG_ADD_RANDOM 10 /* Contributes to random pool */ #define QUEUE_FLAG_SAME_FORCE 12 /* force complete on same CPU */ +#define QUEUE_FLAG_HW_WC 18 /* Write back caching supported */ #define QUEUE_FLAG_INIT_DONE 14 /* queue is initialized */ #define QUEUE_FLAG_STABLE_WRITES 15 /* don't modify blks until WB is done */ #define QUEUE_FLAG_POLL 16 /* IO polling enabled if set */ |