> This is what I'd expect if the volume has only had a mkfs done and > then mounted and umounted. No files. What do you get for > > btrfs ins dump-s -fa /dev/mapper/think--big-home
(attached) Also tried btrfs check -b /dev/mapper/think--big-home, but that errored: # btrfs check -b /dev/mapper/think--big-home volumes.c:1588: btrfs_chunk_readonly: Assertion `!ce` failed. btrfs(+0x50940)[0x56351dc8f940] btrfs(+0x50967)[0x56351dc8f967] btrfs(btrfs_chunk_readonly+0x5a)[0x56351dc91c93] btrfs(btrfs_read_block_groups+0x1dc)[0x56351dc8749b] btrfs(btrfs_setup_all_roots+0x33b)[0x56351dc82adc] btrfs(+0x43ed8)[0x56351dc82ed8] btrfs(open_ctree_fs_info+0xd5)[0x56351dc82ffd] btrfs(cmd_check+0x457)[0x56351dc6c332] btrfs(main+0x139)[0x56351dc4efab] /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf1)[0x7efee8d6d3f1] btrfs(_start+0x2a)[0x56351dc4efea] So, you reckon going back to an older version of btrfs-progs might be worth a shot then?
superblock: bytenr=65536, device=/dev/mapper/think--big-home --------------------------------------------------------- csum_type 0 (crc32c) csum_size 4 csum 0xa64b343b [match] bytenr 65536 flags 0x1 ( WRITTEN ) magic _BHRfS_M [match] fsid 7f1ce0ed-5986-43ae-b0dd-727eee19fd08 label generation 593818 root 138821632 sys_array_size 226 chunk_root_generation 593818 root_level 0 chunk_root 21020672 chunk_root_level 0 log_root 0 log_root_transid 0 log_root_level 0 total_bytes 254007050240 bytes_used 655360 sectorsize 4096 nodesize 16384 leafsize 16384 stripesize 4096 root_dir 6 num_devices 1 compat_flags 0x0 compat_ro_flags 0x0 incompat_flags 0x69 ( MIXED_BACKREF | COMPRESS_LZO | BIG_METADATA | EXTENDED_IREF ) cache_generation 593818 uuid_tree_generation 593818 dev_item.uuid 59b96438-be86-4397-a842-1e1c6efd7479 dev_item.fsid 7f1ce0ed-5986-43ae-b0dd-727eee19fd08 [match] dev_item.type 0 dev_item.total_bytes 254007050240 dev_item.bytes_used 182066348032 dev_item.io_align 4096 dev_item.io_width 4096 dev_item.sector_size 4096 dev_item.devid 1 dev_item.dev_group 0 dev_item.seek_speed 0 dev_item.bandwidth 0 dev_item.generation 0 sys_chunk_array[2048]: item 0 key (FIRST_CHUNK_TREE CHUNK_ITEM 0) chunk length 4194304 owner 2 stripe_len 65536 type SYSTEM num_stripes 1 stripe 0 devid 1 offset 0 dev uuid: 59b96438-be86-4397-a842-1e1c6efd7479 item 1 key (FIRST_CHUNK_TREE CHUNK_ITEM 20971520) chunk length 8388608 owner 2 stripe_len 65536 type SYSTEM|DUP num_stripes 2 stripe 0 devid 1 offset 20971520 dev uuid: 59b96438-be86-4397-a842-1e1c6efd7479 stripe 1 devid 1 offset 29360128 dev uuid: 59b96438-be86-4397-a842-1e1c6efd7479 backup_roots[4]: backup 0: backup_tree_root: 29360128 gen: 593817 level: 1 backup_chunk_root: 20971520 gen: 591139 level: 1 backup_extent_root: 29376512 gen: 593817 level: 1 backup_fs_root: 132562944 gen: 593815 level: 0 backup_dev_root: 29409280 gen: 593817 level: 0 backup_csum_root: 29491200 gen: 593817 level: 0 backup_total_bytes: 254007050240 backup_bytes_used: 43532288 backup_num_devices: 1 backup 1: backup_tree_root: 138821632 gen: 593818 level: 0 backup_chunk_root: 21020672 gen: 593818 level: 0 backup_extent_root: 138805248 gen: 593818 level: 0 backup_fs_root: 132562944 gen: 593815 level: 0 backup_dev_root: 132841472 gen: 593818 level: 0 backup_csum_root: 138870784 gen: 593818 level: 0 backup_total_bytes: 254007050240 backup_bytes_used: 655360 backup_num_devices: 1 backup 2: backup_tree_root: 138788864 gen: 593815 level: 1 backup_chunk_root: 20971520 gen: 591139 level: 1 backup_extent_root: 132841472 gen: 593815 level: 1 backup_fs_root: 132562944 gen: 593815 level: 0 backup_dev_root: 1018118144 gen: 592983 level: 0 backup_csum_root: 134725632 gen: 593815 level: 0 backup_total_bytes: 254007050240 backup_bytes_used: 43532288 backup_num_devices: 1 backup 3: backup_tree_root: 138870784 gen: 593816 level: 1 backup_chunk_root: 20971520 gen: 591139 level: 1 backup_extent_root: 138887168 gen: 593816 level: 1 backup_fs_root: 132562944 gen: 593815 level: 0 backup_dev_root: 1018118144 gen: 592983 level: 0 backup_csum_root: 138952704 gen: 593816 level: 0 backup_total_bytes: 254007050240 backup_bytes_used: 43532288 backup_num_devices: 1 superblock: bytenr=67108864, device=/dev/mapper/think--big-home --------------------------------------------------------- csum_type 0 (crc32c) csum_size 4 csum 0x062a1cf5 [match] bytenr 67108864 flags 0x1 ( WRITTEN ) magic _BHRfS_M [match] fsid 7f1ce0ed-5986-43ae-b0dd-727eee19fd08 label generation 593818 root 138821632 sys_array_size 226 chunk_root_generation 593818 root_level 0 chunk_root 21020672 chunk_root_level 0 log_root 0 log_root_transid 0 log_root_level 0 total_bytes 254007050240 bytes_used 655360 sectorsize 4096 nodesize 16384 leafsize 16384 stripesize 4096 root_dir 6 num_devices 1 compat_flags 0x0 compat_ro_flags 0x0 incompat_flags 0x69 ( MIXED_BACKREF | COMPRESS_LZO | BIG_METADATA | EXTENDED_IREF ) cache_generation 593818 uuid_tree_generation 593818 dev_item.uuid 59b96438-be86-4397-a842-1e1c6efd7479 dev_item.fsid 7f1ce0ed-5986-43ae-b0dd-727eee19fd08 [match] dev_item.type 0 dev_item.total_bytes 254007050240 dev_item.bytes_used 182066348032 dev_item.io_align 4096 dev_item.io_width 4096 dev_item.sector_size 4096 dev_item.devid 1 dev_item.dev_group 0 dev_item.seek_speed 0 dev_item.bandwidth 0 dev_item.generation 0 sys_chunk_array[2048]: item 0 key (FIRST_CHUNK_TREE CHUNK_ITEM 0) chunk length 4194304 owner 2 stripe_len 65536 type SYSTEM num_stripes 1 stripe 0 devid 1 offset 0 dev uuid: 59b96438-be86-4397-a842-1e1c6efd7479 item 1 key (FIRST_CHUNK_TREE CHUNK_ITEM 20971520) chunk length 8388608 owner 2 stripe_len 65536 type SYSTEM|DUP num_stripes 2 stripe 0 devid 1 offset 20971520 dev uuid: 59b96438-be86-4397-a842-1e1c6efd7479 stripe 1 devid 1 offset 29360128 dev uuid: 59b96438-be86-4397-a842-1e1c6efd7479 backup_roots[4]: backup 0: backup_tree_root: 29360128 gen: 593817 level: 1 backup_chunk_root: 20971520 gen: 591139 level: 1 backup_extent_root: 29376512 gen: 593817 level: 1 backup_fs_root: 132562944 gen: 593815 level: 0 backup_dev_root: 29409280 gen: 593817 level: 0 backup_csum_root: 29491200 gen: 593817 level: 0 backup_total_bytes: 254007050240 backup_bytes_used: 43532288 backup_num_devices: 1 backup 1: backup_tree_root: 138821632 gen: 593818 level: 0 backup_chunk_root: 21020672 gen: 593818 level: 0 backup_extent_root: 138805248 gen: 593818 level: 0 backup_fs_root: 132562944 gen: 593815 level: 0 backup_dev_root: 132841472 gen: 593818 level: 0 backup_csum_root: 138870784 gen: 593818 level: 0 backup_total_bytes: 254007050240 backup_bytes_used: 655360 backup_num_devices: 1 backup 2: backup_tree_root: 138788864 gen: 593815 level: 1 backup_chunk_root: 20971520 gen: 591139 level: 1 backup_extent_root: 132841472 gen: 593815 level: 1 backup_fs_root: 132562944 gen: 593815 level: 0 backup_dev_root: 1018118144 gen: 592983 level: 0 backup_csum_root: 134725632 gen: 593815 level: 0 backup_total_bytes: 254007050240 backup_bytes_used: 43532288 backup_num_devices: 1 backup 3: backup_tree_root: 138870784 gen: 593816 level: 1 backup_chunk_root: 20971520 gen: 591139 level: 1 backup_extent_root: 138887168 gen: 593816 level: 1 backup_fs_root: 132562944 gen: 593815 level: 0 backup_dev_root: 1018118144 gen: 592983 level: 0 backup_csum_root: 138952704 gen: 593816 level: 0 backup_total_bytes: 254007050240 backup_bytes_used: 43532288 backup_num_devices: 1