diff options
Diffstat (limited to 'fs/btrfs/super.c')
| -rw-r--r-- | fs/btrfs/super.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 100a0442c413..db7d7b803a61 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1000,10 +1000,20 @@ int btrfs_sync_fs(struct super_block *sb, int wait) */ if (fs_info->pending_changes == 0) return 0; + /* + * A non-blocking test if the fs is frozen. We must not + * start a new transaction here otherwise a deadlock + * happens. The pending operations are delayed to the + * next commit after thawing. + */ + if (__sb_start_write(sb, SB_FREEZE_WRITE, false)) + __sb_end_write(sb, SB_FREEZE_WRITE); + else + return 0; trans = btrfs_start_transaction(root, 0); - } else { - return PTR_ERR(trans); } + if (IS_ERR(trans)) + return PTR_ERR(trans); } return btrfs_commit_transaction(trans, root); } @@ -1704,7 +1714,7 @@ static int btrfs_calc_avail_data_space(struct btrfs_root *root, u64 *free_bytes) avail_space = device->total_bytes - device->bytes_used; /* align with stripe_len */ - do_div(avail_space, BTRFS_STRIPE_LEN); + avail_space = div_u64(avail_space, BTRFS_STRIPE_LEN); avail_space *= BTRFS_STRIPE_LEN; /* |