On Wed, Apr 15, 2015 at 02:51:44PM +1000, Dave Chinner wrote:
> From: Dave Chinner <dchinner@xxxxxxxxxx>
>
> Clarify and separate the buffer mapping logic so that the direct IO mapping is
> not tangled up in propagating the extent status to teh mapping buffer. This
> makes it easier to extend the direct IO mapping to use an ioend in future.
>
> Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>
> ---
Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx>
> fs/xfs/xfs_aops.c | 40 +++++++++++++++++++++++++++-------------
> 1 file changed, 27 insertions(+), 13 deletions(-)
>
> diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
> index 3a9b7a1..489ed20 100644
> --- a/fs/xfs/xfs_aops.c
> +++ b/fs/xfs/xfs_aops.c
> @@ -1233,6 +1233,22 @@ xfs_vm_releasepage(
> return try_to_free_buffers(page);
> }
>
> +/*
> + * do all the direct IO specific mapping buffer manipulation here.
> + */
> +static void
> +xfs_map_direct(
> + struct inode *inode,
> + struct buffer_head *bh_result,
> + struct xfs_bmbt_irec *imap,
> + xfs_off_t offset)
> +{
> + if (ISUNWRITTEN(imap)) {
> + bh_result->b_private = inode;
> + set_buffer_defer_completion(bh_result);
> + }
> +}
> +
> STATIC int
> __xfs_get_blocks(
> struct inode *inode,
> @@ -1331,21 +1347,19 @@ __xfs_get_blocks(
> goto out_unlock;
> }
>
> + /*
> + * For unwritten extents do not report a disk address in the buffered
> + * read case (treat as if we're reading into a hole).
> + */
> if (imap.br_startblock != HOLESTARTBLOCK &&
> - imap.br_startblock != DELAYSTARTBLOCK) {
> - /*
> - * For unwritten extents do not report a disk address on
> - * the read case (treat as if we're reading into a hole).
> - */
> - if (create || !ISUNWRITTEN(&imap))
> - xfs_map_buffer(inode, bh_result, &imap, offset);
> - if (create && ISUNWRITTEN(&imap)) {
> - if (direct) {
> - bh_result->b_private = inode;
> - set_buffer_defer_completion(bh_result);
> - }
> + imap.br_startblock != DELAYSTARTBLOCK &&
> + (create || !ISUNWRITTEN(&imap))) {
> + xfs_map_buffer(inode, bh_result, &imap, offset);
> + if (ISUNWRITTEN(&imap))
> set_buffer_unwritten(bh_result);
> - }
> + /* direct IO needs special help */
> + if (create && direct)
> + xfs_map_direct(inode, bh_result, &imap, offset);
> }
>
> /*
> --
> 2.0.0
>
> _______________________________________________
> xfs mailing list
> xfs@xxxxxxxxxxx
> http://oss.sgi.com/mailman/listinfo/xfs
_______________________________________________
xfs mailing list
xfs@xxxxxxxxxxx
http://oss.sgi.com/mailman/listinfo/xfs
