xfs: only reclaim unwritten COW extents periodically

We only want to reclaim preallocations from our periodic work item.
Currently this is archived by looking for a dirty inode, but that check
is rather fragile.  Instead add a flag to xfs_reflink_cancel_cow_* so
that the caller can ask for just cancelling unwritten extents in the COW
fork.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: fix typos in commit message]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
This commit is contained in:
Christoph Hellwig 2017-03-07 16:45:58 -08:00 committed by Darrick J. Wong
parent c771c14baa
commit 3802a34532
6 changed files with 22 additions and 13 deletions

View File

@ -293,7 +293,7 @@ xfs_end_io(
goto done;
if (ioend->io_bio->bi_error) {
error = xfs_reflink_cancel_cow_range(ip,
ioend->io_offset, ioend->io_size);
ioend->io_offset, ioend->io_size, true);
goto done;
}
error = xfs_reflink_end_cow(ip, ioend->io_offset,

View File

@ -1608,7 +1608,7 @@ xfs_inode_free_cowblocks(
xfs_ilock(ip, XFS_IOLOCK_EXCL);
xfs_ilock(ip, XFS_MMAPLOCK_EXCL);
ret = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF);
ret = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, false);
xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
xfs_iunlock(ip, XFS_IOLOCK_EXCL);

View File

@ -1615,7 +1615,7 @@ xfs_itruncate_extents(
/* Remove all pending CoW reservations. */
error = xfs_reflink_cancel_cow_blocks(ip, &tp, first_unmap_block,
last_block);
last_block, true);
if (error)
goto out;

View File

@ -548,14 +548,18 @@ xfs_reflink_trim_irec_to_next_cow(
}
/*
* Cancel all pending CoW reservations for some block range of an inode.
* Cancel CoW reservations for some block range of an inode.
*
* If cancel_real is true this function cancels all COW fork extents for the
* inode; if cancel_real is false, real extents are not cleared.
*/
int
xfs_reflink_cancel_cow_blocks(
struct xfs_inode *ip,
struct xfs_trans **tpp,
xfs_fileoff_t offset_fsb,
xfs_fileoff_t end_fsb)
xfs_fileoff_t end_fsb,
bool cancel_real)
{
struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
struct xfs_bmbt_irec got, del;
@ -579,7 +583,7 @@ xfs_reflink_cancel_cow_blocks(
&idx, &got, &del);
if (error)
break;
} else {
} else if (del.br_state == XFS_EXT_UNWRITTEN || cancel_real) {
xfs_trans_ijoin(*tpp, ip, 0);
xfs_defer_init(&dfops, &firstfsb);
@ -621,13 +625,17 @@ xfs_reflink_cancel_cow_blocks(
}
/*
* Cancel all pending CoW reservations for some byte range of an inode.
* Cancel CoW reservations for some byte range of an inode.
*
* If cancel_real is true this function cancels all COW fork extents for the
* inode; if cancel_real is false, real extents are not cleared.
*/
int
xfs_reflink_cancel_cow_range(
struct xfs_inode *ip,
xfs_off_t offset,
xfs_off_t count)
xfs_off_t count,
bool cancel_real)
{
struct xfs_trans *tp;
xfs_fileoff_t offset_fsb;
@ -653,7 +661,8 @@ xfs_reflink_cancel_cow_range(
xfs_trans_ijoin(tp, ip, 0);
/* Scrape out the old CoW reservations */
error = xfs_reflink_cancel_cow_blocks(ip, &tp, offset_fsb, end_fsb);
error = xfs_reflink_cancel_cow_blocks(ip, &tp, offset_fsb, end_fsb,
cancel_real);
if (error)
goto out_cancel;
@ -1450,7 +1459,7 @@ next:
* We didn't find any shared blocks so turn off the reflink flag.
* First, get rid of any leftover CoW mappings.
*/
error = xfs_reflink_cancel_cow_blocks(ip, tpp, 0, NULLFILEOFF);
error = xfs_reflink_cancel_cow_blocks(ip, tpp, 0, NULLFILEOFF, true);
if (error)
return error;

View File

@ -39,9 +39,9 @@ extern void xfs_reflink_trim_irec_to_next_cow(struct xfs_inode *ip,
extern int xfs_reflink_cancel_cow_blocks(struct xfs_inode *ip,
struct xfs_trans **tpp, xfs_fileoff_t offset_fsb,
xfs_fileoff_t end_fsb);
xfs_fileoff_t end_fsb, bool cancel_real);
extern int xfs_reflink_cancel_cow_range(struct xfs_inode *ip, xfs_off_t offset,
xfs_off_t count);
xfs_off_t count, bool cancel_real);
extern int xfs_reflink_end_cow(struct xfs_inode *ip, xfs_off_t offset,
xfs_off_t count);
extern int xfs_reflink_recover_cow(struct xfs_mount *mp);

View File

@ -953,7 +953,7 @@ xfs_fs_destroy_inode(
XFS_STATS_INC(ip->i_mount, vn_remove);
if (xfs_is_reflink_inode(ip)) {
error = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF);
error = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
if (error && !XFS_FORCED_SHUTDOWN(ip->i_mount))
xfs_warn(ip->i_mount,
"Error %d while evicting CoW blocks for inode %llu.",