| Message ID | 20171019065942.18813-14-hch@lst.de (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Thu, Oct 19, 2017 at 08:59:40AM +0200, Christoph Hellwig wrote: > Rewrite xfs_bmap_collapse_extents so that we don't rely on extent indices > except for iterating over them. Not being able to iterate to the next > extent is a sufficient exit condition, and we don't need to do any extent > count games given that: > > a) we already flushed all delalloc extents past our start offset > before doing the operation > b) xfs_iext_count() includes delalloc extents anyway > > Signed-off-by: Christoph Hellwig <hch@lst.de> Looks ok, Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> > --- > fs/xfs/libxfs/xfs_bmap.c | 54 +++++++++++------------------------------------- > 1 file changed, 12 insertions(+), 42 deletions(-) > > diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c > index 2de9458903b6..4c89fdacda90 100644 > --- a/fs/xfs/libxfs/xfs_bmap.c > +++ b/fs/xfs/libxfs/xfs_bmap.c > @@ -5626,8 +5626,6 @@ xfs_bmap_collapse_extents( > struct xfs_btree_cur *cur = NULL; > struct xfs_bmbt_irec got, prev; > xfs_extnum_t current_ext; > - xfs_extnum_t total_extents; > - xfs_extnum_t stop_extent; > xfs_fileoff_t new_startoff; > int error = 0; > int logflags = 0; > @@ -5658,52 +5656,31 @@ xfs_bmap_collapse_extents( > cur->bc_private.b.flags = 0; > } > > - /* > - * There may be delalloc extents in the data fork before the range we > - * are collapsing out, so we cannot use the count of real extents here. > - * Instead we have to calculate it from the incore fork. > - */ > - total_extents = xfs_iext_count(ifp); > - if (total_extents == 0) { > - *done = true; > - goto del_cursor; > - } > - > - /* > - * Look up the extent index for the fsb where we start shifting. We can > - * henceforth iterate with current_ext as extent list changes are locked > - * out via ilock. > - * > - * If next_fsb lies in a hole beyond which there are no extents we are > - * done. > - */ > if (!xfs_iext_lookup_extent(ip, ifp, *next_fsb, ¤t_ext, &got)) { > *done = true; > goto del_cursor; > } > XFS_WANT_CORRUPTED_RETURN(mp, !isnullstartblock(got.br_startblock)); > > - stop_extent = total_extents; > - if (current_ext >= stop_extent) { > - error = -EIO; > - goto del_cursor; > - } > - > new_startoff = got.br_startoff - offset_shift_fsb; > - if (current_ext) { > - xfs_iext_get_extent(ifp, current_ext - 1, &prev); > + if (xfs_iext_get_extent(ifp, current_ext - 1, &prev)) { > if (new_startoff < prev.br_startoff + prev.br_blockcount) { > error = -EINVAL; > goto del_cursor; > } > > - /* check whether to merge the extent or shift it down */ > if (xfs_bmse_can_merge(&prev, &got, offset_shift_fsb)) { > error = xfs_bmse_merge(ip, whichfork, offset_shift_fsb, > current_ext, &got, &prev, cur, > &logflags, dfops); > if (error) > goto del_cursor; > + > + /* update got after merge */ > + if (!xfs_iext_get_extent(ifp, current_ext, &got)) { > + *done = true; > + goto del_cursor; > + } > goto done; > } > } else { > @@ -5717,20 +5694,13 @@ xfs_bmap_collapse_extents( > cur, &logflags, dfops, new_startoff); > if (error) > goto del_cursor; > - current_ext++; > -done: > - /* > - * If there was an extent merge during the shift, the extent > - * count can change. Update the total and grade the next record. > - */ > - total_extents = xfs_iext_count(ifp); > - stop_extent = total_extents; > - if (current_ext == stop_extent) { > - *done = true; > - goto del_cursor; > + > + if (!xfs_iext_get_extent(ifp, ++current_ext, &got)) { > + *done = true; > + goto del_cursor; > } > - xfs_iext_get_extent(ifp, current_ext, &got); > > +done: > *next_fsb = got.br_startoff; > del_cursor: > if (cur) > -- > 2.14.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-xfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c index 2de9458903b6..4c89fdacda90 100644 --- a/fs/xfs/libxfs/xfs_bmap.c +++ b/fs/xfs/libxfs/xfs_bmap.c @@ -5626,8 +5626,6 @@ xfs_bmap_collapse_extents( struct xfs_btree_cur *cur = NULL; struct xfs_bmbt_irec got, prev; xfs_extnum_t current_ext; - xfs_extnum_t total_extents; - xfs_extnum_t stop_extent; xfs_fileoff_t new_startoff; int error = 0; int logflags = 0; @@ -5658,52 +5656,31 @@ xfs_bmap_collapse_extents( cur->bc_private.b.flags = 0; } - /* - * There may be delalloc extents in the data fork before the range we - * are collapsing out, so we cannot use the count of real extents here. - * Instead we have to calculate it from the incore fork. - */ - total_extents = xfs_iext_count(ifp); - if (total_extents == 0) { - *done = true; - goto del_cursor; - } - - /* - * Look up the extent index for the fsb where we start shifting. We can - * henceforth iterate with current_ext as extent list changes are locked - * out via ilock. - * - * If next_fsb lies in a hole beyond which there are no extents we are - * done. - */ if (!xfs_iext_lookup_extent(ip, ifp, *next_fsb, ¤t_ext, &got)) { *done = true; goto del_cursor; } XFS_WANT_CORRUPTED_RETURN(mp, !isnullstartblock(got.br_startblock)); - stop_extent = total_extents; - if (current_ext >= stop_extent) { - error = -EIO; - goto del_cursor; - } - new_startoff = got.br_startoff - offset_shift_fsb; - if (current_ext) { - xfs_iext_get_extent(ifp, current_ext - 1, &prev); + if (xfs_iext_get_extent(ifp, current_ext - 1, &prev)) { if (new_startoff < prev.br_startoff + prev.br_blockcount) { error = -EINVAL; goto del_cursor; } - /* check whether to merge the extent or shift it down */ if (xfs_bmse_can_merge(&prev, &got, offset_shift_fsb)) { error = xfs_bmse_merge(ip, whichfork, offset_shift_fsb, current_ext, &got, &prev, cur, &logflags, dfops); if (error) goto del_cursor; + + /* update got after merge */ + if (!xfs_iext_get_extent(ifp, current_ext, &got)) { + *done = true; + goto del_cursor; + } goto done; } } else { @@ -5717,20 +5694,13 @@ xfs_bmap_collapse_extents( cur, &logflags, dfops, new_startoff); if (error) goto del_cursor; - current_ext++; -done: - /* - * If there was an extent merge during the shift, the extent - * count can change. Update the total and grade the next record. - */ - total_extents = xfs_iext_count(ifp); - stop_extent = total_extents; - if (current_ext == stop_extent) { - *done = true; - goto del_cursor; + + if (!xfs_iext_get_extent(ifp, ++current_ext, &got)) { + *done = true; + goto del_cursor; } - xfs_iext_get_extent(ifp, current_ext, &got); +done: *next_fsb = got.br_startoff; del_cursor: if (cur)
Rewrite xfs_bmap_collapse_extents so that we don't rely on extent indices except for iterating over them. Not being able to iterate to the next extent is a sufficient exit condition, and we don't need to do any extent count games given that: a) we already flushed all delalloc extents past our start offset before doing the operation b) xfs_iext_count() includes delalloc extents anyway Signed-off-by: Christoph Hellwig <hch@lst.de> --- fs/xfs/libxfs/xfs_bmap.c | 54 +++++++++++------------------------------------- 1 file changed, 12 insertions(+), 42 deletions(-)