To help implement free space tree checker in user space some kernel
function are necessary, namely iterating/deleting/adding freespace
items, some internal search functions. Functions to populate a block
group based on the extent tree. The code is largely copy/paste from
the kernel with locking eliminated (i.e free_space_lock). It supports
reading/writing of both bitmap and extent based FST trees.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When btrfs check detects a freespace tree extent which ends beyond the
blockgroup containing it a misleading error messages is printed. For
example if we have the following extent in the freespace tree:
item 5 key (30408704 FREE_SPACE_INFO 1073741824) itemoff 16259 itemsize 8
free space info extent count 3 flags 0
item 6 key (30425088 FREE_SPACE_EXTENT 49152) itemoff 16259 itemsize 0
free space extent
item 7 key (30507008 FREE_SPACE_EXTENT 65536) itemoff 16259 itemsize 0
free space extent
item 8 key (30654464 FREE_SPACE_EXTENT 14524648038063310901) itemoff 16259 itemsize 0
Clearly the last extent is corrupted so we should print something
along the lines of:
free space extent ends at 14524648038063310901, beyond end of block group 30408704-1104150528
Instead currently this is printed:
free space extent ends at 30654464, beyond end of block group 30408704-1104150528
So instead of printing the actual erroneous end, we print the beginning
of the extent. Fix this by printing the actual corrupted end.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This function actually uses only the extent_buffer arg but takes 3
arguments. Furthermore, it's current interface doesn't even mirror
the kernel counterpart. Just remove the extra arguments.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This reuses the existing code for checking the free space cache, we just
need to load the free space tree. While we do that, we check a couple of
invariants on the free space tree itself. This requires pulling in some
code from the kernel to exclude the super stripes.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Nikolay Borisov