@@ -1679,6 +1679,11 @@ struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
if (location->objectid == BTRFS_FREE_SPACE_TREE_OBJECTID)
return fs_info->free_space_root ? fs_info->free_space_root :
ERR_PTR(-ENOENT);
+ if (location->objectid == BTRFS_DEDUPE_TREE_OBJECTID) {
+ if (fs_info->dedupe_enabled && fs_info->dedupe_info)
+ return fs_info->dedupe_info->dedupe_root;
+ return ERR_PTR(-ENOENT);
+ }
again:
root = btrfs_lookup_fs_root(fs_info, location->objectid);
if (root) {
@@ -577,7 +577,8 @@ static int is_cowonly_root(u64 root_objectid)
root_objectid == BTRFS_CSUM_TREE_OBJECTID ||
root_objectid == BTRFS_UUID_TREE_OBJECTID ||
root_objectid == BTRFS_QUOTA_TREE_OBJECTID ||
- root_objectid == BTRFS_FREE_SPACE_TREE_OBJECTID)
+ root_objectid == BTRFS_FREE_SPACE_TREE_OBJECTID ||
+ root_objectid == BTRFS_DEDUPE_TREE_OBJECTID)
return 1;
return 0;
}
A missing branch in btrfs_get_fs_root() is making dedupe_root read from disk, and REF_COWS bit set. This makes btrfs balance treating dedupe_root as fs root, and reusing the old dedupe root bytenr to drop tree ref, causing the following kernel warning after metadata balancing: BTRFS error (device sdb6): unable to find ref byte nr 29736960 parent 0 root 11 owner 0 offset 0 ------------[ cut here ]------------ WARNING: CPU: 1 PID: 19113 at fs/btrfs/extent-tree.c:6636 __btrfs_free_extent.isra.66+0xb6d/0xd20 [btrfs]() BTRFS: Transaction aborted (error -2) Modules linked in: btrfs(O) xor zlib_deflate raid6_pq xfs [last unloaded: btrfs] CPU: 1 PID: 19113 Comm: btrfs Tainted: G W O 4.5.0-rc5+ #2 Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 0000000000000000 ffff880035b0ba18 ffffffff813771ff ffff880035b0ba60 ffffffffa06a810a ffff880035b0ba50 ffffffff810bcb81 ffff88003c45c528 0000000001c5c000 00000000fffffffe ffff88003dc8c520 0000000000000000 Call Trace: [<ffffffff813771ff>] dump_stack+0x67/0x98 [<ffffffff810bcb81>] warn_slowpath_common+0x81/0xc0 [<ffffffff810bcc07>] warn_slowpath_fmt+0x47/0x50 [<ffffffffa06028fd>] __btrfs_free_extent.isra.66+0xb6d/0xd20 [btrfs] [<ffffffffa0606d4d>] __btrfs_run_delayed_refs.constprop.71+0x96d/0x1560 [btrfs] [<ffffffff81202ad9>] ? cmpxchg_double_slab.isra.68+0x149/0x160 [<ffffffff81106a1d>] ? trace_hardirqs_on+0xd/0x10 [<ffffffffa060a5ce>] btrfs_run_delayed_refs+0x8e/0x2d0 [btrfs] [<ffffffffa06209fe>] btrfs_commit_transaction+0x3e/0xb50 [btrfs] [<ffffffffa069f26e>] ? btrfs_dedupe_disable+0x28e/0x2c0 [btrfs] [<ffffffff812035c3>] ? kfree+0x223/0x270 [<ffffffffa069f27a>] btrfs_dedupe_disable+0x29a/0x2c0 [btrfs] [<ffffffffa065e403>] btrfs_ioctl+0x2363/0x2a40 [btrfs] [<ffffffff8116b12a>] ? __audit_syscall_entry+0xaa/0xf0 [<ffffffff81137ce6>] ? current_kernel_time64+0x56/0xa0 [<ffffffff8122080e>] do_vfs_ioctl+0x8e/0x690 [<ffffffff8116b12a>] ? __audit_syscall_entry+0xaa/0xf0 [<ffffffff8122c181>] ? __fget_light+0x61/0x90 [<ffffffff81220e84>] SyS_ioctl+0x74/0x80 [<ffffffff8180ad57>] entry_SYSCALL_64_fastpath+0x12/0x6f ---[ end trace 618d5a5bc21d6a7c ]--- Fix it by adding corresponding branch for btrfs_get_fs_root(). Reported-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> --- fs/btrfs/disk-io.c | 5 +++++ fs/btrfs/relocation.c | 3 ++- 2 files changed, 7 insertions(+), 1 deletion(-)