fsck needs to be able to open a damaged FS, which means open_ctree needs
to be able to return a damaged FS.
This adds a new open_ctree_fs_info which can be used to open any and all
roots that are valid. btrfs-debug-tree is changed to use it.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
When building on ppc64 I hit a number of warnings in printf:
btrfs-map-logical.c:69: error: format ‘%Lu’ expects type ‘long long
unsigned int’, but argument 4 has type ‘u64’
Fix them.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Hugo Mills <hugo@carfax.org.uk>
gcc-4.6 (as shipped in Fedora) turns on -Wunused-but-set-variable by
default, which breaks the build when combined with -Wall, e.g.:
debug-tree.c: In function ‘print_extent_leaf’:
debug-tree.c:45:13: error: variable ‘last_len’ set but not used [-Werror=unused-but-set-variable]
debug-tree.c:44:13: error: variable ‘last’ set but not used [-Werror=unused-but-set-variable]
debug-tree.c:41:21: error: variable ‘item’ set but not used [-Werror=unused-but-set-variable]
cc1: all warnings being treated as errors
This patch fixes the errors by removing the unused variables.
Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Hugo Mills <hugo@carfax.org.uk>
the root extent buffer of a tree may not be a leaf, so we must get the right
size by its level when reading it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit introduces a new kind of back reference for btrfs metadata.
Once a filesystem has been mounted with this commit, IT WILL NO LONGER
BE MOUNTABLE BY OLDER KERNELS.
The new back ref provides information about pointer's key, level and in which
tree the pointer lives. This information allow us to find the pointer by
searching the tree. The shortcoming of the new back ref is that it only works
for pointers in tree blocks referenced by their owner trees.
This is mostly a problem for snapshots, where resolving one of these fuzzy back
references would be O(number_of_snapshots) and quite slow. The solution used
here is to use the fuzzy back references in the common case where a given tree
block is only referenced by one root, and use the full back references when
multiple roots have a reference
output objectid in btrfs_disk_key with human readable strings.
Other updates are included for more readable output.
Thanks Fengguang's fix to this patch.
Signed-off-by: Shen Feng <shen@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
The offset field in struct btrfs_extent_ref records the position
inside file that file extent is referenced by. In the new back
reference system, tree leaves holding reference to file extent
are recorded explicitly. We can quickly scan these tree leaves, so the
offset field is not required.
This patch also makes the back reference system check the objectid
when extents are being deleted
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
This patch makes the back reference system to explicit record the
location of parent node for all types of extents. The location of
parent node is placed into the offset field of backref key. Every
time a tree block is balanced, the back references for the affected
lower level extents are updated.