btrfs-progs: Fix negative eb's ref_cnt in btrfs-calc-size

btrfs-calc-size show following warning:
 # btrfs-calc-size /dev/sda6
 Calculating size of root tree
 ...
 extent_io.c:582: free_extent_buffer: Assertion `eb->refs < 0` failed.
 ./btrfs-calc-size[0x41d642]
 ./btrfs-calc-size(free_extent_buffer+0x70)[0x41e1c1]
 ./btrfs-calc-size(btrfs_free_fs_root+0x11)[0x40e1e8]
 ./btrfs-calc-size[0x40e215]
 ./btrfs-calc-size(rb_free_nodes+0x1d)[0x4326fe]
 ./btrfs-calc-size(close_ctree+0x3f3)[0x40f9ea]
 ./btrfs-calc-size(main+0x200)[0x431b4e]
 /lib64/libc.so.6(__libc_start_main+0xf5)[0x3858621d65]
 ./btrfs-calc-size[0x407009]

Reason:
 path in calc_root_size() is only used to save node data,
 it don't hold ref_cnt for each eb in.
 Using btrfs_free_path() to free path will reduce these eb
 again, and cause many problems, as negative ref_cnt or
 invalid memory access.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>

0 files changed, 0 insertions, 0 deletions