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authorChristoph Hellwig <hch@lst.de>2024-06-17 08:04:40 +0200
committerJens Axboe <axboe@kernel.dk>2024-06-19 15:58:28 +0200
commit1122c0c1cc71f740fa4d5f14f239194e06a1d5e7 (patch)
tree690fcda48991904d6916c6f6e0f2205e37511531 /arch/um
parentblock: remove blk_flush_policy (diff)
downloadlinux-1122c0c1cc71f740fa4d5f14f239194e06a1d5e7.tar.xz
linux-1122c0c1cc71f740fa4d5f14f239194e06a1d5e7.zip
block: move cache control settings out of queue->flags
Move the cache control settings into the queue_limits so that the flags can be set atomically with the device queue frozen. Add new features and flags field for the driver set flags, and internal (usually sysfs-controlled) flags in the block layer. Note that we'll eventually remove enough field from queue_limits to bring it back to the previous size. The disable flag is inverted compared to the previous meaning, which means it now survives a rescan, similar to the max_sectors and max_discard_sectors user limits. The FLUSH and FUA flags are now inherited by blk_stack_limits, which simplified the code in dm a lot, but also causes a slight behavior change in that dm-switch and dm-unstripe now advertise a write cache despite setting num_flush_bios to 0. The I/O path will handle this gracefully, but as far as I can tell the lack of num_flush_bios and thus flush support is a pre-existing data integrity bug in those targets that really needs fixing, after which a non-zero num_flush_bios should be required in dm for targets that map to underlying devices. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Hannes Reinecke <hare@suse.de> Link: https://lore.kernel.org/r/20240617060532.127975-14-hch@lst.de Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'arch/um')
-rw-r--r--arch/um/drivers/ubd_kern.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index cdcb75a68989..19e01691ea0e 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -835,6 +835,7 @@ static int ubd_add(int n, char **error_out)
struct queue_limits lim = {
.max_segments = MAX_SG,
.seg_boundary_mask = PAGE_SIZE - 1,
+ .features = BLK_FEAT_WRITE_CACHE,
};
struct gendisk *disk;
int err = 0;
@@ -882,7 +883,6 @@ static int ubd_add(int n, char **error_out)
}
blk_queue_flag_set(QUEUE_FLAG_NONROT, disk->queue);
- blk_queue_write_cache(disk->queue, true, false);
disk->major = UBD_MAJOR;
disk->first_minor = n << UBD_SHIFT;
disk->minors = 1 << UBD_SHIFT;