On Thu, Jan 31, 2019 at 08:55:21AM +0100, Christoph Hellwig wrote:
> No need to deal with the transaction and the inode locking in the
> caller. Also move to automatic unlocking on transaction commit or
> cancel to simplify the code a little more.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> fs/xfs/libxfs/xfs_bmap.c | 33 +++++++++++++++++++++++++++++----
> fs/xfs/libxfs/xfs_bmap.h | 6 +++---
> fs/xfs/xfs_iomap.c | 32 ++++----------------------------
> 3 files changed, 36 insertions(+), 35 deletions(-)
>
> diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
> index 818cd018d510..408a6da14849 100644
> --- a/fs/xfs/libxfs/xfs_bmap.c
> +++ b/fs/xfs/libxfs/xfs_bmap.c
> @@ -4446,16 +4446,32 @@ xfs_bmapi_write(
> */
> int
> xfs_bmapi_convert_delalloc(
> - struct xfs_trans *tp,
> struct xfs_inode *ip,
> int whichfork,
> xfs_fileoff_t offset_fsb,
> - struct xfs_bmbt_irec *imap)
> + struct xfs_bmbt_irec *imap,
> + unsigned int *seq)
> {
> struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
> + struct xfs_mount *mp = ip->i_mount;
> struct xfs_bmalloca bma = { NULL };
> + struct xfs_trans *tp;
> int error;
>
> + /*
> + * Space for the extent and indirect blocks was reserved when the
> + * delalloc extent was created so there's no need to do so here.
> + */
> + error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0,
> + XFS_TRANS_RESERVE, &tp);
> + if (error)
> + return error;
> +
> + xfs_ilock(ip, XFS_ILOCK_EXCL);
> + xfs_trans_ijoin(tp, ip, XFS_ILOCK_EXCL);
> +
> + *seq = READ_ONCE(ifp->if_seq);
> +
seq is going to change once we do the allocation. I think you want to
move this further down to where we set imap, otherwise looks good.
Brian
> if (!xfs_iext_lookup_extent(ip, ifp, offset_fsb, &bma.icur, &bma.got) ||
> bma.got.br_startoff > offset_fsb) {
> /*
> @@ -4464,7 +4480,8 @@ xfs_bmapi_convert_delalloc(
> * might have moved the extent to the data fork in the meantime.
> */
> WARN_ON_ONCE(whichfork != XFS_COW_FORK);
> - return -EAGAIN;
> + error = -EAGAIN;
> + goto out_trans_cancel;
> }
>
> /*
> @@ -4473,7 +4490,7 @@ xfs_bmapi_convert_delalloc(
> */
> if (!isnullstartblock(bma.got.br_startblock)) {
> *imap = bma.got;
> - return 0;
> + goto out_trans_cancel;
> }
>
> bma.tp = tp;
> @@ -4510,8 +4527,16 @@ xfs_bmapi_convert_delalloc(
>
> error = xfs_bmap_btree_to_extents(tp, ip, bma.cur, &bma.logflags,
> whichfork);
> + if (error)
> + goto out_finish;
> +
> + xfs_bmapi_finish(&bma, whichfork, 0);
> + return xfs_trans_commit(tp);
> +
> out_finish:
> xfs_bmapi_finish(&bma, whichfork, error);
> +out_trans_cancel:
> + xfs_trans_cancel(tp);
> return error;
> }
>
> diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h
> index 5bdfa8001f07..78b190b6e908 100644
> --- a/fs/xfs/libxfs/xfs_bmap.h
> +++ b/fs/xfs/libxfs/xfs_bmap.h
> @@ -223,9 +223,9 @@ int xfs_bmapi_reserve_delalloc(struct xfs_inode *ip, int whichfork,
> xfs_fileoff_t off, xfs_filblks_t len, xfs_filblks_t prealloc,
> struct xfs_bmbt_irec *got, struct xfs_iext_cursor *cur,
> int eof);
> -int xfs_bmapi_convert_delalloc(struct xfs_trans *tp, struct xfs_inode *ip,
> - int whichfork, xfs_fileoff_t offset_fsb,
> - struct xfs_bmbt_irec *imap);
> +int xfs_bmapi_convert_delalloc(struct xfs_inode *ip, int whichfork,
> + xfs_fileoff_t offset_fsb, struct xfs_bmbt_irec *imap,
> + unsigned int *seq);
>
> static inline void
> xfs_bmap_add_free(
> diff --git a/fs/xfs/xfs_iomap.c b/fs/xfs/xfs_iomap.c
> index b7c1b279057b..39be741cac5a 100644
> --- a/fs/xfs/xfs_iomap.c
> +++ b/fs/xfs/xfs_iomap.c
> @@ -684,11 +684,9 @@ xfs_iomap_write_allocate(
> unsigned int *seq)
> {
> struct xfs_mount *mp = ip->i_mount;
> - struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
> xfs_fileoff_t offset_fsb;
> xfs_fileoff_t map_start_fsb;
> xfs_extlen_t map_count_fsb;
> - struct xfs_trans *tp;
> int error = 0;
>
> /*
> @@ -716,17 +714,8 @@ xfs_iomap_write_allocate(
> /*
> * Allocate in a loop because it may take several attempts to
> * allocate real blocks for a contiguous delalloc extent if free
> - * space is sufficiently fragmented. Note that space for the
> - * extent and indirect blocks was reserved when the delalloc
> - * extent was created so there's no need to do so here.
> + * space is sufficiently fragmented.
> */
> - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, 0, 0,
> - XFS_TRANS_RESERVE, &tp);
> - if (error)
> - return error;
> -
> - xfs_ilock(ip, XFS_ILOCK_EXCL);
> - xfs_trans_ijoin(tp, ip, 0);
>
> /*
> * ilock was dropped since imap was populated which means it
> @@ -737,17 +726,10 @@ xfs_iomap_write_allocate(
> * caller. We'll trim it down to the caller's most recently
> * validated range before we return.
> */
> - error = xfs_bmapi_convert_delalloc(tp, ip, whichfork,
> - offset_fsb, imap);
> - if (error)
> - goto trans_cancel;
> -
> - error = xfs_trans_commit(tp);
> + error = xfs_bmapi_convert_delalloc(ip, whichfork, offset_fsb,
> + imap, seq);
> if (error)
> - goto error0;
> -
> - *seq = READ_ONCE(ifp->if_seq);
> - xfs_iunlock(ip, XFS_ILOCK_EXCL);
> + return error;
>
> /*
> * See if we were able to allocate an extent that covers at
> @@ -766,12 +748,6 @@ xfs_iomap_write_allocate(
> return 0;
> }
> }
> -
> -trans_cancel:
> - xfs_trans_cancel(tp);
> -error0:
> - xfs_iunlock(ip, XFS_ILOCK_EXCL);
> - return error;
> }
>
> int
> --
> 2.20.1
>
