On Tue, Aug 08, 2023 at 09:15:53AM -0700, Christoph Hellwig wrote:
> Closing the block devices logically belongs into xfs_free_buftarg, So instead
> of open coding it in the caller move it there and add a check for the s_bdev
> so that the main device isn't close as that's done by the VFS helper.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> fs/xfs/xfs_buf.c | 5 +++++
> fs/xfs/xfs_super.c | 12 ++----------
> 2 files changed, 7 insertions(+), 10 deletions(-)
>
> diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
> index 83b8702030f71d..c57e6e03dfa80c 100644
> --- a/fs/xfs/xfs_buf.c
> +++ b/fs/xfs/xfs_buf.c
> @@ -1938,6 +1938,8 @@ void
> xfs_free_buftarg(
> struct xfs_buftarg *btp)
> {
> + struct block_device *bdev = btp->bt_bdev;
> +
> unregister_shrinker(&btp->bt_shrinker);
> ASSERT(percpu_counter_sum(&btp->bt_io_count) == 0);
> percpu_counter_destroy(&btp->bt_io_count);
> @@ -1945,6 +1947,9 @@ xfs_free_buftarg(
>
> blkdev_issue_flush(btp->bt_bdev);
> fs_put_dax(btp->bt_daxdev, btp->bt_mount);
> + /* the main block device is closed by kill_block_super */
> + if (bdev != btp->bt_mount->m_super->s_bdev)
> + blkdev_put(bdev, btp->bt_mount->m_super);
Hmm... I feel like this would be cleaner if the data dev buftarg could
get its own refcount separate from super_block.s_bdev, but I looked
through the code and couldn't identify a simple way to do that. Soo...
Reviewed-by: Darrick J. Wong <djwong@xxxxxxxxxx>
--D
>
> kmem_free(btp);
> }
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index f00d1162815d19..37b1b763a0bef0 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -399,18 +399,10 @@ STATIC void
> xfs_close_devices(
> struct xfs_mount *mp)
> {
> - if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
> - struct block_device *logdev = mp->m_logdev_targp->bt_bdev;
> -
> + if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp)
> xfs_free_buftarg(mp->m_logdev_targp);
> - blkdev_put(logdev, mp->m_super);
> - }
> - if (mp->m_rtdev_targp) {
> - struct block_device *rtdev = mp->m_rtdev_targp->bt_bdev;
> -
> + if (mp->m_rtdev_targp)
> xfs_free_buftarg(mp->m_rtdev_targp);
> - blkdev_put(rtdev, mp->m_super);
> - }
> xfs_free_buftarg(mp->m_ddev_targp);
> }
>
> --
> 2.39.2
>
