diff mbox

[4/6] xfs: introduce a new xfs_inode_has_cow_data helper

Message ID 20180710060528.4071-5-hch@lst.de (mailing list archive)
State Superseded
Headers show

Commit Message

Christoph Hellwig July 10, 2018, 6:05 a.m. UTC
We have a few places that already check if an inode has actual data in
the COW fork to avoid work on reflink inodes that do not actually have
outstanding COW blocks.  There are a few more places that can avoid
working if doing the same check, so add a documented helper for this
condition and use it in all places where it makes sense.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/xfs/xfs_aops.c      |  4 ++--
 fs/xfs/xfs_bmap_util.c |  2 +-
 fs/xfs/xfs_icache.c    | 10 ++++------
 fs/xfs/xfs_inode.c     |  3 +--
 fs/xfs/xfs_inode.h     |  9 +++++++++
 fs/xfs/xfs_reflink.c   |  2 +-
 6 files changed, 18 insertions(+), 12 deletions(-)

Comments

Darrick J. Wong July 11, 2018, 4:24 p.m. UTC | #1
On Tue, Jul 10, 2018 at 08:05:26AM +0200, Christoph Hellwig wrote:
> We have a few places that already check if an inode has actual data in
> the COW fork to avoid work on reflink inodes that do not actually have
> outstanding COW blocks.  There are a few more places that can avoid
> working if doing the same check, so add a documented helper for this
> condition and use it in all places where it makes sense.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Looks ok, I think.
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>

--D

> ---
>  fs/xfs/xfs_aops.c      |  4 ++--
>  fs/xfs/xfs_bmap_util.c |  2 +-
>  fs/xfs/xfs_icache.c    | 10 ++++------
>  fs/xfs/xfs_inode.c     |  3 +--
>  fs/xfs/xfs_inode.h     |  9 +++++++++
>  fs/xfs/xfs_reflink.c   |  2 +-
>  6 files changed, 18 insertions(+), 12 deletions(-)
> 
> diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
> index f4d3252236c1..814100d27343 100644
> --- a/fs/xfs/xfs_aops.c
> +++ b/fs/xfs/xfs_aops.c
> @@ -338,7 +338,7 @@ xfs_map_blocks(
>  	imap_valid = offset_fsb >= wpc->imap.br_startoff &&
>  		     offset_fsb < wpc->imap.br_startoff + wpc->imap.br_blockcount;
>  	if (imap_valid &&
> -	    (!xfs_is_reflink_inode(ip) || wpc->io_type == XFS_IO_COW))
> +	    (!xfs_inode_has_cow_data(ip) || wpc->io_type == XFS_IO_COW))
>  		return 0;
>  
>  	if (XFS_FORCED_SHUTDOWN(mp))
> @@ -363,7 +363,7 @@ xfs_map_blocks(
>  	 * Check if this is offset is covered by a COW extents, and if yes use
>  	 * it directly instead of looking up anything in the data fork.
>  	 */
> -	if (xfs_is_reflink_inode(ip) &&
> +	if (xfs_inode_has_cow_data(ip) &&
>  	    xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &icur, &imap) &&
>  	    imap.br_startoff <= offset_fsb) {
>  		xfs_iunlock(ip, XFS_ILOCK_SHARED);
> diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
> index da561882c349..d78f8300607f 100644
> --- a/fs/xfs/xfs_bmap_util.c
> +++ b/fs/xfs/xfs_bmap_util.c
> @@ -1280,7 +1280,7 @@ xfs_prepare_shift(
>  	 * we've flushed all the dirty data out to disk to avoid having
>  	 * CoW extents at the wrong offsets.
>  	 */
> -	if (xfs_is_reflink_inode(ip)) {
> +	if (xfs_inode_has_cow_data(ip)) {
>  		error = xfs_reflink_cancel_cow_range(ip, offset, NULLFILEOFF,
>  				true);
>  		if (error)
> diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
> index 79f344fa8b14..fdae4c2d461e 100644
> --- a/fs/xfs/xfs_icache.c
> +++ b/fs/xfs/xfs_icache.c
> @@ -1697,14 +1697,13 @@ xfs_inode_clear_eofblocks_tag(
>   */
>  static bool
>  xfs_prep_free_cowblocks(
> -	struct xfs_inode	*ip,
> -	struct xfs_ifork	*ifp)
> +	struct xfs_inode	*ip)
>  {
>  	/*
>  	 * Just clear the tag if we have an empty cow fork or none at all. It's
>  	 * possible the inode was fully unshared since it was originally tagged.
>  	 */
> -	if (!xfs_is_reflink_inode(ip) || !ifp->if_bytes) {
> +	if (!xfs_inode_has_cow_data(ip)) {
>  		trace_xfs_inode_free_cowblocks_invalid(ip);
>  		xfs_inode_clear_cowblocks_tag(ip);
>  		return false;
> @@ -1742,11 +1741,10 @@ xfs_inode_free_cowblocks(
>  	void			*args)
>  {
>  	struct xfs_eofblocks	*eofb = args;
> -	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
>  	int			match;
>  	int			ret = 0;
>  
> -	if (!xfs_prep_free_cowblocks(ip, ifp))
> +	if (!xfs_prep_free_cowblocks(ip))
>  		return 0;
>  
>  	if (eofb) {
> @@ -1771,7 +1769,7 @@ xfs_inode_free_cowblocks(
>  	 * Check again, nobody else should be able to dirty blocks or change
>  	 * the reflink iflag now that we have the first two locks held.
>  	 */
> -	if (xfs_prep_free_cowblocks(ip, ifp))
> +	if (xfs_prep_free_cowblocks(ip))
>  		ret = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, false);
>  
>  	xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
> diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
> index b6da446ae946..2036e49f7e15 100644
> --- a/fs/xfs/xfs_inode.c
> +++ b/fs/xfs/xfs_inode.c
> @@ -1868,7 +1868,6 @@ xfs_inactive(
>  	xfs_inode_t	*ip)
>  {
>  	struct xfs_mount	*mp;
> -	struct xfs_ifork	*cow_ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
>  	int			error;
>  	int			truncate = 0;
>  
> @@ -1889,7 +1888,7 @@ xfs_inactive(
>  		return;
>  
>  	/* Try to clean out the cow blocks if there are any. */
> -	if (xfs_is_reflink_inode(ip) && cow_ifp->if_bytes > 0)
> +	if (xfs_inode_has_cow_data(ip))
>  		xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
>  
>  	if (VFS_I(ip)->i_nlink != 0) {
> diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
> index 1f910d2ae73a..82d27a295336 100644
> --- a/fs/xfs/xfs_inode.h
> +++ b/fs/xfs/xfs_inode.h
> @@ -198,6 +198,15 @@ static inline bool xfs_is_reflink_inode(struct xfs_inode *ip)
>  	return ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK;
>  }
>  
> +/*
> + * Check if an inode has any data in the COW fork.  This might be often false
> + * even for inodes with the reflink flag when there is no pending COW operation.
> + */
> +static inline bool xfs_inode_has_cow_data(struct xfs_inode *ip)
> +{
> +	return ip->i_cowfp && ip->i_cowfp->if_bytes;
> +}
> +
>  /*
>   * In-core inode flags.
>   */
> diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
> index 49e4913fa779..789310c547e6 100644
> --- a/fs/xfs/xfs_reflink.c
> +++ b/fs/xfs/xfs_reflink.c
> @@ -494,7 +494,7 @@ xfs_reflink_cancel_cow_blocks(
>  	struct xfs_defer_ops		dfops;
>  	int				error = 0;
>  
> -	if (!xfs_is_reflink_inode(ip))
> +	if (!xfs_inode_has_cow_data(ip))
>  		return 0;
>  	if (!xfs_iext_lookup_extent_before(ip, ifp, &end_fsb, &icur, &got))
>  		return 0;
> -- 
> 2.18.0
> 
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diff mbox

Patch

diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c
index f4d3252236c1..814100d27343 100644
--- a/fs/xfs/xfs_aops.c
+++ b/fs/xfs/xfs_aops.c
@@ -338,7 +338,7 @@  xfs_map_blocks(
 	imap_valid = offset_fsb >= wpc->imap.br_startoff &&
 		     offset_fsb < wpc->imap.br_startoff + wpc->imap.br_blockcount;
 	if (imap_valid &&
-	    (!xfs_is_reflink_inode(ip) || wpc->io_type == XFS_IO_COW))
+	    (!xfs_inode_has_cow_data(ip) || wpc->io_type == XFS_IO_COW))
 		return 0;
 
 	if (XFS_FORCED_SHUTDOWN(mp))
@@ -363,7 +363,7 @@  xfs_map_blocks(
 	 * Check if this is offset is covered by a COW extents, and if yes use
 	 * it directly instead of looking up anything in the data fork.
 	 */
-	if (xfs_is_reflink_inode(ip) &&
+	if (xfs_inode_has_cow_data(ip) &&
 	    xfs_iext_lookup_extent(ip, ip->i_cowfp, offset_fsb, &icur, &imap) &&
 	    imap.br_startoff <= offset_fsb) {
 		xfs_iunlock(ip, XFS_ILOCK_SHARED);
diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c
index da561882c349..d78f8300607f 100644
--- a/fs/xfs/xfs_bmap_util.c
+++ b/fs/xfs/xfs_bmap_util.c
@@ -1280,7 +1280,7 @@  xfs_prepare_shift(
 	 * we've flushed all the dirty data out to disk to avoid having
 	 * CoW extents at the wrong offsets.
 	 */
-	if (xfs_is_reflink_inode(ip)) {
+	if (xfs_inode_has_cow_data(ip)) {
 		error = xfs_reflink_cancel_cow_range(ip, offset, NULLFILEOFF,
 				true);
 		if (error)
diff --git a/fs/xfs/xfs_icache.c b/fs/xfs/xfs_icache.c
index 79f344fa8b14..fdae4c2d461e 100644
--- a/fs/xfs/xfs_icache.c
+++ b/fs/xfs/xfs_icache.c
@@ -1697,14 +1697,13 @@  xfs_inode_clear_eofblocks_tag(
  */
 static bool
 xfs_prep_free_cowblocks(
-	struct xfs_inode	*ip,
-	struct xfs_ifork	*ifp)
+	struct xfs_inode	*ip)
 {
 	/*
 	 * Just clear the tag if we have an empty cow fork or none at all. It's
 	 * possible the inode was fully unshared since it was originally tagged.
 	 */
-	if (!xfs_is_reflink_inode(ip) || !ifp->if_bytes) {
+	if (!xfs_inode_has_cow_data(ip)) {
 		trace_xfs_inode_free_cowblocks_invalid(ip);
 		xfs_inode_clear_cowblocks_tag(ip);
 		return false;
@@ -1742,11 +1741,10 @@  xfs_inode_free_cowblocks(
 	void			*args)
 {
 	struct xfs_eofblocks	*eofb = args;
-	struct xfs_ifork	*ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
 	int			match;
 	int			ret = 0;
 
-	if (!xfs_prep_free_cowblocks(ip, ifp))
+	if (!xfs_prep_free_cowblocks(ip))
 		return 0;
 
 	if (eofb) {
@@ -1771,7 +1769,7 @@  xfs_inode_free_cowblocks(
 	 * Check again, nobody else should be able to dirty blocks or change
 	 * the reflink iflag now that we have the first two locks held.
 	 */
-	if (xfs_prep_free_cowblocks(ip, ifp))
+	if (xfs_prep_free_cowblocks(ip))
 		ret = xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, false);
 
 	xfs_iunlock(ip, XFS_MMAPLOCK_EXCL);
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index b6da446ae946..2036e49f7e15 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -1868,7 +1868,6 @@  xfs_inactive(
 	xfs_inode_t	*ip)
 {
 	struct xfs_mount	*mp;
-	struct xfs_ifork	*cow_ifp = XFS_IFORK_PTR(ip, XFS_COW_FORK);
 	int			error;
 	int			truncate = 0;
 
@@ -1889,7 +1888,7 @@  xfs_inactive(
 		return;
 
 	/* Try to clean out the cow blocks if there are any. */
-	if (xfs_is_reflink_inode(ip) && cow_ifp->if_bytes > 0)
+	if (xfs_inode_has_cow_data(ip))
 		xfs_reflink_cancel_cow_range(ip, 0, NULLFILEOFF, true);
 
 	if (VFS_I(ip)->i_nlink != 0) {
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 1f910d2ae73a..82d27a295336 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -198,6 +198,15 @@  static inline bool xfs_is_reflink_inode(struct xfs_inode *ip)
 	return ip->i_d.di_flags2 & XFS_DIFLAG2_REFLINK;
 }
 
+/*
+ * Check if an inode has any data in the COW fork.  This might be often false
+ * even for inodes with the reflink flag when there is no pending COW operation.
+ */
+static inline bool xfs_inode_has_cow_data(struct xfs_inode *ip)
+{
+	return ip->i_cowfp && ip->i_cowfp->if_bytes;
+}
+
 /*
  * In-core inode flags.
  */
diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c
index 49e4913fa779..789310c547e6 100644
--- a/fs/xfs/xfs_reflink.c
+++ b/fs/xfs/xfs_reflink.c
@@ -494,7 +494,7 @@  xfs_reflink_cancel_cow_blocks(
 	struct xfs_defer_ops		dfops;
 	int				error = 0;
 
-	if (!xfs_is_reflink_inode(ip))
+	if (!xfs_inode_has_cow_data(ip))
 		return 0;
 	if (!xfs_iext_lookup_extent_before(ip, ifp, &end_fsb, &icur, &got))
 		return 0;