diff options
author | Keith Busch <kbusch@kernel.org> | 2022-06-10 12:58:29 -0700 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2022-06-27 06:29:11 -0600 |
commit | b1a000d3b8ec582da64bb644be633e5a0beffcbf (patch) | |
tree | 960fc00a20dbe8733f847f441205dae3be20b189 /include | |
parent | 5debd9691c3ac64c3acd6867c264ad38bbe48cdc (diff) |
block: relax direct io memory alignment
Use the address alignment requirements from the block_device for direct
io instead of requiring addresses be aligned to the block size. User
space can discover the alignment requirements from the dma_alignment
queue attribute.
User space can specify any hardware compatible DMA offset for each
segment, but every segment length is still required to be a multiple of
the block size.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220610195830.3574005-11-kbusch@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include')
-rw-r--r-- | include/linux/blkdev.h | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 0b8bc1fe0b2c..886c44e97434 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -424,6 +424,11 @@ struct request_queue { unsigned long nr_requests; /* Max # of requests */ unsigned int dma_pad_mask; + /* + * Drivers that set dma_alignment to less than 511 must be prepared to + * handle individual bvec's that are not a multiple of a SECTOR_SIZE + * due to possible offsets. + */ unsigned int dma_alignment; #ifdef CONFIG_BLK_INLINE_ENCRYPTION |