Btrfs: fix no reserved space for writing out inode cache
I-node cache forgets to reserve the space when writing out it. And when
we do some stress test, such as synctest, it will trigger WARN_ON() in
use_block_rsv().
WARNING: at fs/btrfs/extent-tree.c:5718 btrfs_alloc_free_block+0xbf/0x281 [btrfs]()
...
Call Trace:
[<ffffffff8104df86>] warn_slowpath_common+0x80/0x98
[<ffffffff8104dfb3>] warn_slowpath_null+0x15/0x17
[<ffffffffa0369c60>] btrfs_alloc_free_block+0xbf/0x281 [btrfs]
[<ffffffff810cbcb8>] ? __set_page_dirty_nobuffers+0xfe/0x108
[<ffffffffa035c040>] __btrfs_cow_block+0x118/0x3b5 [btrfs]
[<ffffffffa035c7ba>] btrfs_cow_block+0x103/0x14e [btrfs]
[<ffffffffa035e4c4>] btrfs_search_slot+0x249/0x6a4 [btrfs]
[<ffffffffa036d086>] btrfs_lookup_inode+0x2a/0x8a [btrfs]
[<ffffffffa03788b7>] btrfs_update_inode+0xaa/0x141 [btrfs]
[<ffffffffa036d7ec>] btrfs_save_ino_cache+0xea/0x202 [btrfs]
[<ffffffffa03a761e>] ? btrfs_update_reloc_root+0x17e/0x197 [btrfs]
[<ffffffffa0373867>] commit_fs_roots+0xaa/0x158 [btrfs]
[<ffffffffa03746a6>] btrfs_commit_transaction+0x405/0x731 [btrfs]
[<ffffffff810690df>] ? wake_up_bit+0x25/0x25
[<ffffffffa039d652>] ? btrfs_log_dentry_safe+0x43/0x51 [btrfs]
[<ffffffffa0381c5f>] btrfs_sync_file+0x16a/0x198 [btrfs]
[<ffffffff81122806>] ? mntput+0x21/0x23
[<ffffffff8112d150>] vfs_fsync_range+0x18/0x21
[<ffffffff8112d170>] vfs_fsync+0x17/0x19
[<ffffffff8112d316>] do_fsync+0x29/0x3e
[<ffffffff8112d348>] sys_fsync+0xb/0xf
[<ffffffff81468352>] system_call_fastpath+0x16/0x1b
Sometimes it causes BUG_ON() in the reservation code of the delayed inode
is triggered.
So we must reserve enough space for inode cache.
Note: If we can not reserve the enough space for inode cache, we will
give up writing out it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
1 file changed
