Refactor xfs_reflink_end_cow_extent() into separate parts which process
the CoW range and commit the transaction.
This refactoring will be used in future for when it is required to commit
a range of extents as a single transaction, similar to how it was done
pre-commit d6f215f359637.
Signed-off-by: John Garry <john.g.garry@oracle.com>
---
fs/xfs/xfs_reflink.c | 73 ++++++++++++++++++++++++++------------------
1 file changed, 43 insertions(+), 30 deletions(-)
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 59f7fc16eb80..8428f7b26ee6 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -786,35 +786,19 @@ xfs_reflink_update_quota(
* requirements as low as possible.
*/
STATIC int
-xfs_reflink_end_cow_extent(
+xfs_reflink_end_cow_extent_locked(
+ struct xfs_trans *tp,
struct xfs_inode *ip,
xfs_fileoff_t *offset_fsb,
xfs_fileoff_t end_fsb)
{
struct xfs_iext_cursor icur;
struct xfs_bmbt_irec got, del, data;
- struct xfs_mount *mp = ip->i_mount;
- struct xfs_trans *tp;
struct xfs_ifork *ifp = xfs_ifork_ptr(ip, XFS_COW_FORK);
- unsigned int resblks;
int nmaps;
bool isrt = XFS_IS_REALTIME_INODE(ip);
int error;
- resblks = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK);
- error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0,
- XFS_TRANS_RESERVE, &tp);
- if (error)
- return error;
-
- /*
- * Lock the inode. We have to ijoin without automatic unlock because
- * the lead transaction is the refcountbt record deletion; the data
- * fork update follows as a deferred log item.
- */
- xfs_ilock(ip, XFS_ILOCK_EXCL);
- xfs_trans_ijoin(tp, ip, 0);
-
/*
* In case of racing, overlapping AIO writes no COW extents might be
* left by the time I/O completes for the loser of the race. In that
@@ -823,7 +807,7 @@ xfs_reflink_end_cow_extent(
if (!xfs_iext_lookup_extent(ip, ifp, *offset_fsb, &icur, &got) ||
got.br_startoff >= end_fsb) {
*offset_fsb = end_fsb;
- goto out_cancel;
+ return 0;
}
/*
@@ -837,7 +821,7 @@ xfs_reflink_end_cow_extent(
if (!xfs_iext_next_extent(ifp, &icur, &got) ||
got.br_startoff >= end_fsb) {
*offset_fsb = end_fsb;
- goto out_cancel;
+ return 0;
}
}
del = got;
@@ -846,14 +830,14 @@ xfs_reflink_end_cow_extent(
error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK,
XFS_IEXT_REFLINK_END_COW_CNT);
if (error)
- goto out_cancel;
+ return error;
/* Grab the corresponding mapping in the data fork. */
nmaps = 1;
error = xfs_bmapi_read(ip, del.br_startoff, del.br_blockcount, &data,
&nmaps, 0);
if (error)
- goto out_cancel;
+ return error;
/* We can only remap the smaller of the two extent sizes. */
data.br_blockcount = min(data.br_blockcount, del.br_blockcount);
@@ -882,7 +866,7 @@ xfs_reflink_end_cow_extent(
error = xfs_bunmapi(NULL, ip, data.br_startoff,
data.br_blockcount, 0, 1, &done);
if (error)
- goto out_cancel;
+ return error;
ASSERT(done);
}
@@ -899,17 +883,46 @@ xfs_reflink_end_cow_extent(
/* Remove the mapping from the CoW fork. */
xfs_bmap_del_extent_cow(ip, &icur, &got, &del);
- error = xfs_trans_commit(tp);
- xfs_iunlock(ip, XFS_ILOCK_EXCL);
- if (error)
- return error;
-
/* Update the caller about how much progress we made. */
*offset_fsb = del.br_startoff + del.br_blockcount;
return 0;
+}
-out_cancel:
- xfs_trans_cancel(tp);
+
+/*
+ * Remap part of the CoW fork into the data fork.
+ *
+ * We aim to remap the range starting at @offset_fsb and ending at @end_fsb
+ * into the data fork; this function will remap what it can (at the end of the
+ * range) and update @end_fsb appropriately. Each remap gets its own
+ * transaction because we can end up merging and splitting bmbt blocks for
+ * every remap operation and we'd like to keep the block reservation
+ * requirements as low as possible.
+ */
+STATIC int
+xfs_reflink_end_cow_extent(
+ struct xfs_inode *ip,
+ xfs_fileoff_t *offset_fsb,
+ xfs_fileoff_t end_fsb)
+{
+ struct xfs_mount *mp = ip->i_mount;
+ struct xfs_trans *tp;
+ unsigned int resblks;
+ int error;
+
+ resblks = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK);
+ error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0,
+ XFS_TRANS_RESERVE, &tp);
+ if (error)
+ return error;
+ xfs_ilock(ip, XFS_ILOCK_EXCL);
+ xfs_trans_ijoin(tp, ip, 0);
+
+ error = xfs_reflink_end_cow_extent_locked(tp, ip, offset_fsb, end_fsb);
+ if (error)
+ xfs_trans_cancel(tp);
+ else
+ error = xfs_trans_commit(tp);
xfs_iunlock(ip, XFS_ILOCK_EXCL);
return error;
}
--
2.31.1On Thu, Feb 13, 2025 at 01:56:11PM +0000, John Garry wrote:
> Refactor xfs_reflink_end_cow_extent() into separate parts which process
> the CoW range and commit the transaction.
>
> This refactoring will be used in future for when it is required to commit
> a range of extents as a single transaction, similar to how it was done
> pre-commit d6f215f359637.
>
> Signed-off-by: John Garry <john.g.garry@oracle.com>
> ---
> fs/xfs/xfs_reflink.c | 73 ++++++++++++++++++++++++++------------------
> 1 file changed, 43 insertions(+), 30 deletions(-)
>
> diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
> index 59f7fc16eb80..8428f7b26ee6 100644
> --- a/fs/xfs/xfs_reflink.c
> +++ b/fs/xfs/xfs_reflink.c
> @@ -786,35 +786,19 @@ xfs_reflink_update_quota(
> * requirements as low as possible.
> */
> STATIC int
> -xfs_reflink_end_cow_extent(
> +xfs_reflink_end_cow_extent_locked(
> + struct xfs_trans *tp,
> struct xfs_inode *ip,
> xfs_fileoff_t *offset_fsb,
> xfs_fileoff_t end_fsb)
> {
> struct xfs_iext_cursor icur;
> struct xfs_bmbt_irec got, del, data;
> - struct xfs_mount *mp = ip->i_mount;
> - struct xfs_trans *tp;
> struct xfs_ifork *ifp = xfs_ifork_ptr(ip, XFS_COW_FORK);
> - unsigned int resblks;
> int nmaps;
> bool isrt = XFS_IS_REALTIME_INODE(ip);
> int error;
>
> - resblks = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK);
> - error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0,
> - XFS_TRANS_RESERVE, &tp);
> - if (error)
> - return error;
> -
> - /*
> - * Lock the inode. We have to ijoin without automatic unlock because
> - * the lead transaction is the refcountbt record deletion; the data
> - * fork update follows as a deferred log item.
> - */
> - xfs_ilock(ip, XFS_ILOCK_EXCL);
> - xfs_trans_ijoin(tp, ip, 0);
> -
> /*
> * In case of racing, overlapping AIO writes no COW extents might be
> * left by the time I/O completes for the loser of the race. In that
> @@ -823,7 +807,7 @@ xfs_reflink_end_cow_extent(
> if (!xfs_iext_lookup_extent(ip, ifp, *offset_fsb, &icur, &got) ||
> got.br_startoff >= end_fsb) {
> *offset_fsb = end_fsb;
> - goto out_cancel;
> + return 0;
> }
>
> /*
> @@ -837,7 +821,7 @@ xfs_reflink_end_cow_extent(
> if (!xfs_iext_next_extent(ifp, &icur, &got) ||
> got.br_startoff >= end_fsb) {
> *offset_fsb = end_fsb;
> - goto out_cancel;
> + return 0;
> }
> }
> del = got;
> @@ -846,14 +830,14 @@ xfs_reflink_end_cow_extent(
> error = xfs_iext_count_extend(tp, ip, XFS_DATA_FORK,
> XFS_IEXT_REFLINK_END_COW_CNT);
> if (error)
> - goto out_cancel;
> + return error;
>
> /* Grab the corresponding mapping in the data fork. */
> nmaps = 1;
> error = xfs_bmapi_read(ip, del.br_startoff, del.br_blockcount, &data,
> &nmaps, 0);
> if (error)
> - goto out_cancel;
> + return error;
>
> /* We can only remap the smaller of the two extent sizes. */
> data.br_blockcount = min(data.br_blockcount, del.br_blockcount);
> @@ -882,7 +866,7 @@ xfs_reflink_end_cow_extent(
> error = xfs_bunmapi(NULL, ip, data.br_startoff,
> data.br_blockcount, 0, 1, &done);
> if (error)
> - goto out_cancel;
> + return error;
> ASSERT(done);
> }
>
> @@ -899,17 +883,46 @@ xfs_reflink_end_cow_extent(
> /* Remove the mapping from the CoW fork. */
> xfs_bmap_del_extent_cow(ip, &icur, &got, &del);
>
> - error = xfs_trans_commit(tp);
> - xfs_iunlock(ip, XFS_ILOCK_EXCL);
> - if (error)
> - return error;
> -
> /* Update the caller about how much progress we made. */
> *offset_fsb = del.br_startoff + del.br_blockcount;
> return 0;
> +}
>
> -out_cancel:
> - xfs_trans_cancel(tp);
> +
> +/*
> + * Remap part of the CoW fork into the data fork.
> + *
> + * We aim to remap the range starting at @offset_fsb and ending at @end_fsb
> + * into the data fork; this function will remap what it can (at the end of the
> + * range) and update @end_fsb appropriately. Each remap gets its own
> + * transaction because we can end up merging and splitting bmbt blocks for
> + * every remap operation and we'd like to keep the block reservation
> + * requirements as low as possible.
> + */
> +STATIC int
> +xfs_reflink_end_cow_extent(
> + struct xfs_inode *ip,
> + xfs_fileoff_t *offset_fsb,
> + xfs_fileoff_t end_fsb)
> +{
> + struct xfs_mount *mp = ip->i_mount;
> + struct xfs_trans *tp;
> + unsigned int resblks;
> + int error;
> +
> + resblks = XFS_EXTENTADD_SPACE_RES(mp, XFS_DATA_FORK);
> + error = xfs_trans_alloc(mp, &M_RES(mp)->tr_write, resblks, 0,
> + XFS_TRANS_RESERVE, &tp);
> + if (error)
> + return error;
> + xfs_ilock(ip, XFS_ILOCK_EXCL);
> + xfs_trans_ijoin(tp, ip, 0);
> +
> + error = xfs_reflink_end_cow_extent_locked(tp, ip, offset_fsb, end_fsb);
Overly long line, but otherwise looks fine. With that fixed,
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
--D
> + if (error)
> + xfs_trans_cancel(tp);
> + else
> + error = xfs_trans_commit(tp);
> xfs_iunlock(ip, XFS_ILOCK_EXCL);
> return error;
> }
> --
> 2.31.1
>
>
On 24/02/2025 20:26, Darrick J. Wong wrote: >> + if (error) >> + return error; >> + xfs_ilock(ip, XFS_ILOCK_EXCL); >> + xfs_trans_ijoin(tp, ip, 0); >> + >> + error = xfs_reflink_end_cow_extent_locked(tp, ip, offset_fsb, end_fsb); > Overly long line, but otherwise looks fine. The limit is 80, right? That line fills out to 80. > With that fixed, > Reviewed-by: "Darrick J. Wong"<djwong@kernel.org> > cheers
On Tue, Feb 25, 2025 at 10:01:32AM +0000, John Garry wrote: > On 24/02/2025 20:26, Darrick J. Wong wrote: > > > + if (error) > > > + return error; > > > + xfs_ilock(ip, XFS_ILOCK_EXCL); > > > + xfs_trans_ijoin(tp, ip, 0); > > > + > > > + error = xfs_reflink_end_cow_extent_locked(tp, ip, offset_fsb, end_fsb); > > Overly long line, but otherwise looks fine. > > The limit is 80, right? That line fills out to 80. Ah, right, forgot that I have vim set up to display the right margin at 72 for emails. --D > > With that fixed, > > Reviewed-by: "Darrick J. Wong"<djwong@kernel.org> > > > > cheers > >
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