From: Josef Bacik josef@toxicpanda.com
commit fca3a45d08782a2bb85e048fb8e3128b1388d7b7 upstream.
The minimum reserve size was adjusted to take into account the height of the tree we are merging, however we can have a root with a level == 0. What we want is root_level + 1 to get the number of nodes we may have to cow. This fixes the enospc_debug warning pops with btrfs/101.
Nikolay: this fixes failures on btrfs/060 btrfs/062 btrfs/063 and btrfs/195 That I was seeing, the call trace was:
[ 3680.515564] ------------[ cut here ]------------ [ 3680.515566] BTRFS: block rsv returned -28 [ 3680.515585] WARNING: CPU: 2 PID: 8339 at fs/btrfs/block-rsv.c:521 btrfs_use_block_rsv+0x162/0x180 [ 3680.515587] Modules linked in: [ 3680.515591] CPU: 2 PID: 8339 Comm: btrfs Tainted: G W 5.9.0-rc8-default #95 [ 3680.515593] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014 [ 3680.515595] RIP: 0010:btrfs_use_block_rsv+0x162/0x180 [ 3680.515600] RSP: 0018:ffffa01ac9753910 EFLAGS: 00010282 [ 3680.515602] RAX: 0000000000000000 RBX: ffff984b34200000 RCX: 0000000000000027 [ 3680.515604] RDX: 0000000000000027 RSI: 0000000000000000 RDI: ffff984b3bd19e28 [ 3680.515606] RBP: 0000000000004000 R08: ffff984b3bd19e20 R09: 0000000000000001 [ 3680.515608] R10: 0000000000000004 R11: 0000000000000046 R12: ffff984b264fdc00 [ 3680.515609] R13: ffff984b13149000 R14: 00000000ffffffe4 R15: ffff984b34200000 [ 3680.515613] FS: 00007f4e2912b8c0(0000) GS:ffff984b3bd00000(0000) knlGS:0000000000000000 [ 3680.515615] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3680.515617] CR2: 00007fab87122150 CR3: 0000000118e42000 CR4: 00000000000006e0 [ 3680.515620] Call Trace: [ 3680.515627] btrfs_alloc_tree_block+0x8b/0x340 [ 3680.515633] ? __lock_acquire+0x51a/0xac0 [ 3680.515646] alloc_tree_block_no_bg_flush+0x4f/0x60 [ 3680.515651] __btrfs_cow_block+0x14e/0x7e0 [ 3680.515662] btrfs_cow_block+0x144/0x2c0 [ 3680.515670] merge_reloc_root+0x4d4/0x610 [ 3680.515675] ? btrfs_lookup_fs_root+0x78/0x90 [ 3680.515686] merge_reloc_roots+0xee/0x280 [ 3680.515695] relocate_block_group+0x2ce/0x5e0 [ 3680.515704] btrfs_relocate_block_group+0x16e/0x310 [ 3680.515711] btrfs_relocate_chunk+0x38/0xf0 [ 3680.515716] btrfs_shrink_device+0x200/0x560 [ 3680.515728] btrfs_rm_device+0x1ae/0x6a6 [ 3680.515744] ? _copy_from_user+0x6e/0xb0 [ 3680.515750] btrfs_ioctl+0x1afe/0x28c0 [ 3680.515755] ? find_held_lock+0x2b/0x80 [ 3680.515760] ? do_user_addr_fault+0x1f8/0x418 [ 3680.515773] ? __x64_sys_ioctl+0x77/0xb0 [ 3680.515775] __x64_sys_ioctl+0x77/0xb0 [ 3680.515781] do_syscall_64+0x31/0x70 [ 3680.515785] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Reported-by: Nikolay Borisov nborisov@suse.com Fixes: 44d354abf33e ("btrfs: relocation: review the call sites which can be interrupted by signal") CC: stable@vger.kernel.org # 5.4+ Reviewed-by: Nikolay Borisov nborisov@suse.com Tested-by: Nikolay Borisov nborisov@suse.com Signed-off-by: Josef Bacik josef@toxicpanda.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/btrfs/relocation.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -1646,6 +1646,7 @@ static noinline_for_stack int merge_relo struct btrfs_root_item *root_item; struct btrfs_path *path; struct extent_buffer *leaf; + int reserve_level; int level; int max_level; int replaced = 0; @@ -1694,7 +1695,8 @@ static noinline_for_stack int merge_relo * Thus the needed metadata size is at most root_level * nodesize, * and * 2 since we have two trees to COW. */ - min_reserved = fs_info->nodesize * btrfs_root_level(root_item) * 2; + reserve_level = max_t(int, 1, btrfs_root_level(root_item)); + min_reserved = fs_info->nodesize * reserve_level * 2; memset(&next_key, 0, sizeof(next_key));
while (1) {