| From 262bb64d60b9e8d1b1a30cfff61eb4ebe1d65f4f Mon Sep 17 00:00:00 2001 |
| From: Martijn Coenen <maco@android.com> |
| Date: Wed, 4 Sep 2019 21:49:01 +0200 |
| Subject: [PATCH] loop: change queue block size to match when using DIO |
| |
| commit 85560117d00f5d528e928918b8f61cadcefff98b upstream. |
| |
| The loop driver assumes that if the passed in fd is opened with |
| O_DIRECT, the caller wants to use direct I/O on the loop device. |
| However, if the underlying block device has a different block size than |
| the loop block queue, direct I/O can't be enabled. Instead of requiring |
| userspace to manually change the blocksize and re-enable direct I/O, |
| just change the queue block sizes to match, as well as the io_min size. |
| |
| Reviewed-by: Christoph Hellwig <hch@lst.de> |
| Signed-off-by: Martijn Coenen <maco@android.com> |
| Signed-off-by: Jens Axboe <axboe@kernel.dk> |
| Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> |
| |
| diff --git a/drivers/block/loop.c b/drivers/block/loop.c |
| index 8e32930f65a1..2f191194d719 100644 |
| --- a/drivers/block/loop.c |
| +++ b/drivers/block/loop.c |
| @@ -1002,6 +1002,16 @@ static int loop_set_fd(struct loop_device *lo, fmode_t mode, |
| if (!(lo_flags & LO_FLAGS_READ_ONLY) && file->f_op->fsync) |
| blk_queue_write_cache(lo->lo_queue, true, false); |
| |
| + if (io_is_direct(lo->lo_backing_file) && inode->i_sb->s_bdev) { |
| + /* In case of direct I/O, match underlying block size */ |
| + unsigned short bsize = bdev_logical_block_size( |
| + inode->i_sb->s_bdev); |
| + |
| + blk_queue_logical_block_size(lo->lo_queue, bsize); |
| + blk_queue_physical_block_size(lo->lo_queue, bsize); |
| + blk_queue_io_min(lo->lo_queue, bsize); |
| + } |
| + |
| loop_update_rotational(lo); |
| loop_update_dio(lo); |
| set_capacity(lo->lo_disk, size); |
| -- |
| 2.7.4 |
| |
