Currently xfs_bmap_local_to_extents_empty expects the caller to set the
for size to 0, which implies freeing if_data. That is highly suboptimal
because the callers need the data in the local fork so that they can
copy it to the newly allocated extent.
Change xfs_bmap_local_to_extents_empty to return the old fork data and
clear if_bytes to zero instead and let the callers free the memory for
the local fork, which allows them to access the data directly while
formatting the extent format data.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
fs/xfs/libxfs/xfs_bmap.c | 13 +++++++------
fs/xfs/libxfs/xfs_bmap.h | 2 +-
2 files changed, 8 insertions(+), 7 deletions(-)
diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index 6053f5e5c71eec..eb826fae8fd878 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -754,31 +754,32 @@ xfs_bmap_extents_to_btree(
/*
* Convert a local file to an extents file.
- * This code is out of bounds for data forks of regular files,
- * since the file data needs to get logged so things will stay consistent.
- * (The bmap-level manipulations are ok, though).
+ *
+ * Returns the content of the old data fork, which needs to be freed by the
+ * caller.
*/
-void
+void *
xfs_bmap_local_to_extents_empty(
struct xfs_trans *tp,
struct xfs_inode *ip,
int whichfork)
{
struct xfs_ifork *ifp = xfs_ifork_ptr(ip, whichfork);
+ void *old_data = ifp->if_data;
ASSERT(whichfork != XFS_COW_FORK);
ASSERT(ifp->if_format == XFS_DINODE_FMT_LOCAL);
- ASSERT(ifp->if_bytes == 0);
ASSERT(ifp->if_nextents == 0);
xfs_bmap_forkoff_reset(ip, whichfork);
ifp->if_data = NULL;
+ ifp->if_bytes = 0;
ifp->if_height = 0;
ifp->if_format = XFS_DINODE_FMT_EXTENTS;
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+ return old_data;
}
-
int /* error */
xfs_bmap_local_to_extents(
xfs_trans_t *tp, /* transaction pointer */
diff --git a/fs/xfs/libxfs/xfs_bmap.h b/fs/xfs/libxfs/xfs_bmap.h
index e98849eb9bbae3..6e0b6081bf3aa5 100644
--- a/fs/xfs/libxfs/xfs_bmap.h
+++ b/fs/xfs/libxfs/xfs_bmap.h
@@ -178,7 +178,7 @@ void xfs_trim_extent(struct xfs_bmbt_irec *irec, xfs_fileoff_t bno,
unsigned int xfs_bmap_compute_attr_offset(struct xfs_mount *mp);
int xfs_bmap_add_attrfork(struct xfs_trans *tp, struct xfs_inode *ip,
int size, int rsvd);
-void xfs_bmap_local_to_extents_empty(struct xfs_trans *tp,
+void *xfs_bmap_local_to_extents_empty(struct xfs_trans *tp,
struct xfs_inode *ip, int whichfork);
int xfs_bmap_local_to_extents(struct xfs_trans *tp, struct xfs_inode *ip,
xfs_extlen_t total, int *logflagsp, int whichfork,
--
2.39.2
