When enabling checksums, tune2fs naively rewrites every extent in the
entire tree! This is unnecessary since we only need to rewrite each
extent tree block; therefore, only rewrite the extent if it's the
first one in an internal extent tree block.
Also, don't bother iterating the extent tree when clearing checksums.
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
misc/tune2fs.c | 49 +++++++++++++++++++++++++++++++++----------------
1 file changed, 33 insertions(+), 16 deletions(-)
diff --git a/misc/tune2fs.c b/misc/tune2fs.c
index d17c8de..ecbdea0 100644
--- a/misc/tune2fs.c
+++ b/misc/tune2fs.c
@@ -442,39 +442,56 @@ static errcode_t rewrite_extents(ext2_filsys fs, ext2_ino_t ino,
{
ext2_extent_handle_t handle;
struct ext2fs_extent extent;
- int op = EXT2_EXTENT_ROOT;
errcode_t errcode;
+ struct ext2_extent_info info;
- if (!(inode->i_flags & EXT4_EXTENTS_FL))
+ if (!(inode->i_flags & EXT4_EXTENTS_FL) ||
+ !EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
+ EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
return 0;
errcode = ext2fs_extent_open(fs, ino, &handle);
if (errcode)
return errcode;
- while (1) {
- errcode = ext2fs_extent_get(handle, op, &extent);
+ errcode = ext2fs_extent_get(handle, EXT2_EXTENT_ROOT, &extent);
+ if (errcode)
+ goto out;
+
+ do {
+ errcode = ext2fs_extent_get_info(handle, &info);
if (errcode)
break;
- /* Root node is in the separately checksummed inode */
- if (op == EXT2_EXTENT_ROOT) {
- op = EXT2_EXTENT_NEXT;
- continue;
+ /*
+ * If this is the first extent in an extent block that we
+ * haven't visited, rewrite the extent to force the ETB
+ * checksum to be rewritten.
+ */
+ if (info.curr_entry == 1 && info.curr_level != 0 &&
+ !(extent.e_flags & EXT2_EXTENT_FLAGS_SECOND_VISIT)) {
+ errcode = ext2fs_extent_replace(handle, 0, &extent);
+ if (errcode)
+ break;
}
- op = EXT2_EXTENT_NEXT;
- /* Only visit the first extent in each extent block */
- if (extent.e_flags & EXT2_EXTENT_FLAGS_SECOND_VISIT)
- continue;
- errcode = ext2fs_extent_replace(handle, 0, &extent);
- if (errcode)
- break;
- }
+ /* Skip to the end of a block of leaf nodes */
+ if (extent.e_flags & EXT2_EXTENT_FLAGS_LEAF) {
+ errcode = ext2fs_extent_get(handle,
+ EXT2_EXTENT_LAST_SIB,
+ &extent);
+ if (errcode)
+ break;
+ }
+ errcode = ext2fs_extent_get(handle, EXT2_EXTENT_NEXT, &extent);
+ } while (errcode == 0);
+
+out:
/* Ok if we run off the end */
if (errcode == EXT2_ET_EXTENT_NO_NEXT)
errcode = 0;
+ ext2fs_extent_free(handle);
return errcode;
}
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