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authorLinus Torvalds <torvalds@linux-foundation.org>2015-02-23 05:05:13 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2015-02-23 05:05:13 +0300
commitfeaf222925cdfbc841a695fd30df8c6d0a694146 (patch)
tree9bba94f19346cd3cba0223741b38885b898491ae /fs/ext4/indirect.c
parentbe5e6616dd74e17fdd8e16ca015cfef94d49b467 (diff)
parent6f30b7e37a8239f9d27db626a1d3427bc7951908 (diff)
downloadlinux-feaf222925cdfbc841a695fd30df8c6d0a694146.tar.xz
Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o: "Ext4 bug fixes. We also reserved code points for encryption and read-only images (for which the implementation is mostly just the reserved code point for a read-only feature :-)" * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: fix indirect punch hole corruption ext4: ignore journal checksum on remount; don't fail ext4: remove duplicate remount check for JOURNAL_CHECKSUM change ext4: fix mmap data corruption in nodelalloc mode when blocksize < pagesize ext4: support read-only images ext4: change to use setup_timer() instead of init_timer() ext4: reserve codepoints used by the ext4 encryption feature jbd2: complain about descriptor block checksum errors
Diffstat (limited to 'fs/ext4/indirect.c')
-rw-r--r--fs/ext4/indirect.c105
1 files changed, 71 insertions, 34 deletions
diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c
index 6b9878a24182..45fe924f82bc 100644
--- a/fs/ext4/indirect.c
+++ b/fs/ext4/indirect.c
@@ -1401,10 +1401,7 @@ end_range:
* to free. Everything was covered by the start
* of the range.
*/
- return 0;
- } else {
- /* Shared branch grows from an indirect block */
- partial2--;
+ goto do_indirects;
}
} else {
/*
@@ -1435,56 +1432,96 @@ end_range:
/* Punch happened within the same level (n == n2) */
partial = ext4_find_shared(inode, n, offsets, chain, &nr);
partial2 = ext4_find_shared(inode, n2, offsets2, chain2, &nr2);
- /*
- * ext4_find_shared returns Indirect structure which
- * points to the last element which should not be
- * removed by truncate. But this is end of the range
- * in punch_hole so we need to point to the next element
- */
- partial2->p++;
- while ((partial > chain) || (partial2 > chain2)) {
- /* We're at the same block, so we're almost finished */
- if ((partial->bh && partial2->bh) &&
- (partial->bh->b_blocknr == partial2->bh->b_blocknr)) {
- if ((partial > chain) && (partial2 > chain2)) {
+
+ /* Free top, but only if partial2 isn't its subtree. */
+ if (nr) {
+ int level = min(partial - chain, partial2 - chain2);
+ int i;
+ int subtree = 1;
+
+ for (i = 0; i <= level; i++) {
+ if (offsets[i] != offsets2[i]) {
+ subtree = 0;
+ break;
+ }
+ }
+
+ if (!subtree) {
+ if (partial == chain) {
+ /* Shared branch grows from the inode */
+ ext4_free_branches(handle, inode, NULL,
+ &nr, &nr+1,
+ (chain+n-1) - partial);
+ *partial->p = 0;
+ } else {
+ /* Shared branch grows from an indirect block */
+ BUFFER_TRACE(partial->bh, "get_write_access");
ext4_free_branches(handle, inode, partial->bh,
- partial->p + 1,
- partial2->p,
+ partial->p,
+ partial->p+1,
(chain+n-1) - partial);
- BUFFER_TRACE(partial->bh, "call brelse");
- brelse(partial->bh);
- BUFFER_TRACE(partial2->bh, "call brelse");
- brelse(partial2->bh);
}
- return 0;
}
+ }
+
+ if (!nr2) {
/*
- * Clear the ends of indirect blocks on the shared branch
- * at the start of the range
+ * ext4_find_shared returns Indirect structure which
+ * points to the last element which should not be
+ * removed by truncate. But this is end of the range
+ * in punch_hole so we need to point to the next element
*/
- if (partial > chain) {
+ partial2->p++;
+ }
+
+ while (partial > chain || partial2 > chain2) {
+ int depth = (chain+n-1) - partial;
+ int depth2 = (chain2+n2-1) - partial2;
+
+ if (partial > chain && partial2 > chain2 &&
+ partial->bh->b_blocknr == partial2->bh->b_blocknr) {
+ /*
+ * We've converged on the same block. Clear the range,
+ * then we're done.
+ */
ext4_free_branches(handle, inode, partial->bh,
- partial->p + 1,
- (__le32 *)partial->bh->b_data+addr_per_block,
- (chain+n-1) - partial);
+ partial->p + 1,
+ partial2->p,
+ (chain+n-1) - partial);
BUFFER_TRACE(partial->bh, "call brelse");
brelse(partial->bh);
- partial--;
+ BUFFER_TRACE(partial2->bh, "call brelse");
+ brelse(partial2->bh);
+ return 0;
}
+
/*
- * Clear the ends of indirect blocks on the shared branch
- * at the end of the range
+ * The start and end partial branches may not be at the same
+ * level even though the punch happened within one level. So, we
+ * give them a chance to arrive at the same level, then walk
+ * them in step with each other until we converge on the same
+ * block.
*/
- if (partial2 > chain2) {
+ if (partial > chain && depth <= depth2) {
+ ext4_free_branches(handle, inode, partial->bh,
+ partial->p + 1,
+ (__le32 *)partial->bh->b_data+addr_per_block,
+ (chain+n-1) - partial);
+ BUFFER_TRACE(partial->bh, "call brelse");
+ brelse(partial->bh);
+ partial--;
+ }
+ if (partial2 > chain2 && depth2 <= depth) {
ext4_free_branches(handle, inode, partial2->bh,
(__le32 *)partial2->bh->b_data,
partial2->p,
- (chain2+n-1) - partial2);
+ (chain2+n2-1) - partial2);
BUFFER_TRACE(partial2->bh, "call brelse");
brelse(partial2->bh);
partial2--;
}
}
+ return 0;
do_indirects:
/* Kill the remaining (whole) subtrees */