linux-stable/fs/btrfs
David Sterba b2f78e8805 btrfs: allow degenerate raid0/raid10
The data on raid0 and raid10 are supposed to be spread over multiple
devices, so the minimum constraints are set to 2 and 4 respectively.
This is an artificial limit and there's some interest to remove it.

Change this to allow raid0 on one device and raid10 on two devices. This
works as expected eg. when converting or removing devices.

The only difference is when raid0 on two devices gets one device
removed. Unpatched would silently create a single profile, while newly
it would be raid0.

The motivation is to allow to preserve the profile type as long as it
possible for some intermediate state (device removal, conversion), or
when there are disks of different size, with raid0 the otherwise
unusable space of the last device will be used too. Similarly for
raid10, though the two largest devices would need to be the same.

Unpatched kernel will mount and use the degenerate profiles just fine
but won't allow any operation that would not satisfy the stricter device
number constraints, eg. not allowing to go from 3 to 2 devices for
raid10 or various profile conversions.

Example output:

  # btrfs fi us -T .
  Overall:
      Device size:                  10.00GiB
      Device allocated:              1.01GiB
      Device unallocated:            8.99GiB
      Device missing:                  0.00B
      Used:                        200.61MiB
      Free (estimated):              9.79GiB      (min: 9.79GiB)
      Free (statfs, df):             9.79GiB
      Data ratio:                       1.00
      Metadata ratio:                   1.00
      Global reserve:                3.25MiB      (used: 0.00B)
      Multiple profiles:                  no

		Data      Metadata  System
  Id Path       RAID0     single    single   Unallocated
  -- ---------- --------- --------- -------- -----------
   1 /dev/sda10   1.00GiB   8.00MiB  1.00MiB     8.99GiB
  -- ---------- --------- --------- -------- -----------
     Total        1.00GiB   8.00MiB  1.00MiB     8.99GiB
     Used       200.25MiB 352.00KiB 16.00KiB

  # btrfs dev us .
  /dev/sda10, ID: 1
     Device size:            10.00GiB
     Device slack:              0.00B
     Data,RAID0/1:            1.00GiB
     Metadata,single:         8.00MiB
     System,single:           1.00MiB
     Unallocated:             8.99GiB

Note "Data,RAID0/1", with btrfs-progs 5.13+ the number of devices per
profile is printed.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:08 +02:00
..
tests btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
acl.c fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
async-thread.c
async-thread.h
backref.c btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
backref.h btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
block-group.c btrfs: rescue: allow ibadroots to skip bad extent tree when reading block group items 2021-08-23 13:19:00 +02:00
block-group.h btrfs: rework chunk allocation to avoid exhaustion of the system chunk array 2021-07-07 17:42:41 +02:00
block-rsv.c btrfs: introduce mount option rescue=ignorebadroots 2020-12-08 15:53:41 +01:00
block-rsv.h
btrfs_inode.h btrfs: remove stale comment and logic from btrfs_inode_in_log() 2021-04-19 17:25:16 +02:00
check-integrity.c btrfs: check-integrity: drop kmap/kunmap for block pages 2021-08-23 13:19:00 +02:00
check-integrity.h
compression.c btrfs: rework btrfs_decompress_buf2page() 2021-08-23 13:19:04 +02:00
compression.h btrfs: rework btrfs_decompress_buf2page() 2021-08-23 13:19:04 +02:00
ctree.c btrfs: make btrfs_next_leaf static inline 2021-08-23 13:19:02 +02:00
ctree.h btrfs: use delalloc_bytes to determine flush amount for shrink_delalloc 2021-08-23 13:19:07 +02:00
delalloc-space.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
delalloc-space.h btrfs: make btrfs_delalloc_reserve_space take btrfs_inode 2020-07-27 12:55:36 +02:00
delayed-inode.c btrfs: stop doing GFP_KERNEL memory allocations in the ref verify tool 2021-08-23 13:19:00 +02:00
delayed-inode.h btrfs: make btrfs_delayed_update_inode take btrfs_inode 2020-12-08 15:54:10 +01:00
delayed-ref.c btrfs: fix lock inversion problem when doing qgroup extent tracing 2021-07-22 15:50:07 +02:00
delayed-ref.h btrfs: only let one thread pre-flush delayed refs in commit 2021-02-08 22:58:56 +01:00
dev-replace.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
dev-replace.h btrfs: zoned: mark block groups to copy for device-replace 2021-02-09 02:46:07 +01:00
dir-item.c btrfs: introduce btrfs_lookup_match_dir 2021-08-23 13:19:02 +02:00
discard.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
discard.h btrfs: cleanup btrfs_discard_update_discardable usage 2020-12-08 15:54:02 +01:00
disk-io.c btrfs: allow read-write for 4K sectorsize on 64K page size systems 2021-08-23 13:19:06 +02:00
disk-io.h btrfs: split alloc_log_tree() 2021-02-09 02:46:07 +01:00
export.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
export.h
extent-io-tree.h btrfs: use fixed width int type for extent_state::state 2020-12-08 15:54:13 +01:00
extent-tree.c btrfs: pass NULL as trans to btrfs_search_slot if we only want to search 2021-08-23 13:19:00 +02:00
extent_io.c btrfs: fix argument type of btrfs_bio_clone_partial() 2021-08-23 13:19:08 +02:00
extent_io.h btrfs: fix argument type of btrfs_bio_clone_partial() 2021-08-23 13:19:08 +02:00
extent_map.c btrfs: fix parameter description of btrfs_add_extent_mapping 2021-02-08 22:58:53 +01:00
extent_map.h
file-item.c btrfs: remove unneeded return variable in btrfs_lookup_file_extent 2021-08-23 13:19:01 +02:00
file.c btrfs: subpage: fix a potential use-after-free in writeback helper 2021-08-23 13:19:05 +02:00
free-space-cache.c btrfs: don't set the full sync flag when truncation does not touch extents 2021-06-21 15:19:05 +02:00
free-space-cache.h btrfs: zoned: track unusable bytes for zones 2021-02-09 02:46:03 +01:00
free-space-tree.c btrfs: fix possible free space tree corruption with online conversion 2021-01-25 18:44:37 +01:00
free-space-tree.h
inode-item.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
inode.c btrfs: do not pin logs too early during renames 2021-08-23 13:19:08 +02:00
ioctl.c btrfs: allow read-write for 4K sectorsize on 64K page size systems 2021-08-23 13:19:06 +02:00
Kconfig btrfs: disable build on platforms having page size 256K 2021-06-22 14:11:57 +02:00
locking.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
locking.h btrfs: remove the recurse parameter from __btrfs_tree_read_lock 2020-12-08 15:54:09 +01:00
lzo.c btrfs: rework lzo_decompress_bio() to make it subpage compatible 2021-08-23 13:19:04 +02:00
Makefile btrfs: move the tree mod log code into its own file 2021-04-19 17:25:16 +02:00
misc.h
ordered-data.c btrfs: remove uptodate parameter from btrfs_dec_test_first_ordered_pending 2021-08-23 13:19:02 +02:00
ordered-data.h btrfs: remove uptodate parameter from btrfs_dec_test_first_ordered_pending 2021-08-23 13:19:02 +02:00
orphan.c
print-tree.c btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
print-tree.h btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
props.c btrfs: props: change how empty value is interpreted 2021-06-22 14:11:58 +02:00
props.h
qgroup.c btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
qgroup.h btrfs: fix lock inversion problem when doing qgroup extent tracing 2021-07-22 15:50:07 +02:00
raid56.c btrfs: constify and cleanup variables in comparators 2021-08-23 13:19:03 +02:00
raid56.h
rcu-string.h
reada.c btrfs: subpage: make readahead work properly 2021-03-16 11:06:21 +01:00
ref-verify.c btrfs: stop doing GFP_KERNEL memory allocations in the ref verify tool 2021-08-23 13:19:00 +02:00
ref-verify.h
reflink.c btrfs: reflink: make copy_inline_to_page() to be subpage compatible 2021-06-21 15:19:10 +02:00
reflink.h
relocation.c btrfs: subpage: fix relocation potentially overwriting last page data 2021-08-23 13:19:06 +02:00
root-tree.c btrfs: qgroup: fix qgroup meta rsv leak for subvolume operations 2020-10-07 12:12:13 +02:00
scrub.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
send.c btrfs: constify and cleanup variables in comparators 2021-08-23 13:19:03 +02:00
send.h btrfs: send: avoid copying file data 2020-10-07 12:13:17 +02:00
space-info.c btrfs: wait on async extents when flushing delalloc 2021-08-23 13:19:07 +02:00
space-info.h btrfs: rip out btrfs_space_info::total_bytes_pinned 2021-06-22 14:55:25 +02:00
struct-funcs.c btrfs: add special case to setget helpers for 64k pages 2021-08-23 13:18:58 +02:00
subpage.c btrfs: subpage: fix a potential use-after-free in writeback helper 2021-08-23 13:19:05 +02:00
subpage.h btrfs: subpage: fix writeback which does not have ordered extent 2021-08-23 13:19:04 +02:00
super.c btrfs: allow read-write for 4K sectorsize on 64K page size systems 2021-08-23 13:19:06 +02:00
sysfs.c btrfs: allow read-write for 4K sectorsize on 64K page size systems 2021-08-23 13:19:06 +02:00
sysfs.h btrfs: split and refactor btrfs_sysfs_remove_devices_dir 2020-10-07 12:12:21 +02:00
transaction.c btrfs: rework chunk allocation to avoid exhaustion of the system chunk array 2021-07-07 17:42:41 +02:00
transaction.h btrfs: rework chunk allocation to avoid exhaustion of the system chunk array 2021-07-07 17:42:41 +02:00
tree-checker.c btrfs: tree-checker: add missing stripe checks for raid1c3/4 profiles 2021-08-23 13:19:03 +02:00
tree-checker.h
tree-defrag.c btrfs: locking: remove all the blocking helpers 2020-12-08 15:54:01 +01:00
tree-log.c btrfs: eliminate some false positives when checking if inode was logged 2021-08-23 13:19:08 +02:00
tree-log.h btrfs: make fast fsyncs wait only for writeback 2020-10-07 12:06:56 +02:00
tree-mod-log.c btrfs: fix race when picking most recent mod log operation for an old root 2021-04-20 19:27:17 +02:00
tree-mod-log.h btrfs: add and use helper to get lowest sequence number for the tree mod log 2021-04-19 17:25:17 +02:00
ulist.c
ulist.h
uuid-tree.c btrfs: remove unnecessary casts in printk 2020-12-08 15:53:52 +01:00
volumes.c btrfs: allow degenerate raid0/raid10 2021-08-23 13:19:08 +02:00
volumes.h btrfs: uninline btrfs_bg_flags_to_raid_index 2021-08-23 13:19:03 +02:00
xattr.c for-5.12-rc1-tag 2021-03-05 12:21:14 -08:00
xattr.h
zlib.c btrfs: rework btrfs_decompress_buf2page() 2021-08-23 13:19:04 +02:00
zoned.c btrfs: use btrfs_next_leaf instead of btrfs_next_item when slots > nritems 2021-08-23 13:19:01 +02:00
zoned.h btrfs: zoned: remove max_zone_append_size logic 2021-08-23 13:18:58 +02:00
zstd.c btrfs: rework btrfs_decompress_buf2page() 2021-08-23 13:19:04 +02:00