xfs: iterate over extents in xfs_iextents_copy

This actually makes the function very slightly less efficient for now as we
detour through the expanded irect format between the in-core extent format
and the on-disk one instead of just endian swapping them.  But with the
incore extent btree the in-core one will use a different format and the
representation will be entirely hidden.  It also happens to make the
function a whole more readable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
This commit is contained in:
Christoph Hellwig 2017-11-03 10:34:42 -07:00 committed by Darrick J. Wong
parent f36bc228e1
commit 71565f4b92

View File

@ -725,9 +725,6 @@ xfs_iext_count(struct xfs_ifork *ifp)
/*
* Convert in-core extents to on-disk form
*
* For either the data or attr fork in extent format, we need to endian convert
* the in-core extent as we place them into the on-disk inode.
*
* In the case of the data fork, the in-core and on-disk fork sizes can be
* different due to delayed allocation extents. We only copy on-disk extents
* here, so callers must always use the physical fork size to determine the
@ -736,55 +733,31 @@ xfs_iext_count(struct xfs_ifork *ifp)
*/
int
xfs_iextents_copy(
xfs_inode_t *ip,
xfs_bmbt_rec_t *dp,
struct xfs_inode *ip,
struct xfs_bmbt_rec *dp,
int whichfork)
{
int state = xfs_bmap_fork_to_state(whichfork);
int copied;
int i;
xfs_ifork_t *ifp;
int nrecs;
xfs_fsblock_t start_block;
struct xfs_ifork *ifp = XFS_IFORK_PTR(ip, whichfork);
struct xfs_bmbt_irec rec;
int copied = 0, i = 0;
ifp = XFS_IFORK_PTR(ip, whichfork);
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_ILOCK_SHARED));
ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL | XFS_ILOCK_SHARED));
ASSERT(ifp->if_bytes > 0);
nrecs = xfs_iext_count(ifp);
ASSERT(nrecs > 0);
/*
* There are some delayed allocation extents in the
* inode, so copy the extents one at a time and skip
* the delayed ones. There must be at least one
* non-delayed extent.
*/
copied = 0;
for (i = 0; i < nrecs; i++) {
xfs_bmbt_rec_host_t *ep = xfs_iext_get_ext(ifp, i);
start_block = xfs_bmbt_get_startblock(ep);
if (isnullstartblock(start_block)) {
/*
* It's a delayed allocation extent, so skip it.
*/
while (xfs_iext_get_extent(ifp, i++, &rec)) {
if (isnullstartblock(rec.br_startblock))
continue;
}
xfs_bmbt_disk_set_all(dp, &rec);
trace_xfs_write_extent(ip, i, state, _RET_IP_);
/* Translate to on disk format */
put_unaligned_be64(ep->l0, &dp->l0);
put_unaligned_be64(ep->l1, &dp->l1);
ASSERT(xfs_bmbt_validate_extent(ip->i_mount, whichfork, dp));
copied += sizeof(struct xfs_bmbt_rec);
dp++;
copied++;
}
ASSERT(copied != 0);
return (copied * (uint)sizeof(xfs_bmbt_rec_t));
ASSERT(copied > 0);
ASSERT(copied <= ifp->if_bytes);
return copied;
}
/*