linux/fs/btrfs
Qu Wenruo 0c89138970 btrfs: relocation: Add introduction of how relocation works
Relocation is one of the most complex part of btrfs, while it's also the
foundation stone for online resizing, profile converting.

For such a complex facility, we should at least have some introduction
to it.

This patch will add an basic introduction at pretty a high level,
explaining:

- What relocation does
- How relocation is done
  Only mentioning how data reloc tree and reloc tree are involved in the
  operation.
  No details like the backref cache, or the data reloc tree contents.
- Which function to refer.

More detailed comments will be added for reloc tree creation, data reloc
tree creation and backref cache.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-03-23 17:01:23 +01:00
..
tests btrfs: Correctly handle empty trees in find_first_clear_extent_bit 2020-01-31 14:01:29 +01:00
acl.c btrfs: cleanup btrfs_setxattr_trans and drop transaction parameter 2019-04-29 19:02:44 +02:00
async-thread.c btrfs: add __pure attribute to functions 2019-11-18 12:46:52 +01:00
async-thread.h btrfs: add __pure attribute to functions 2019-11-18 12:46:52 +01:00
backref.c Btrfs: fix deadlock between fiemap and transaction commits 2019-07-30 18:25:12 +02:00
backref.h btrfs: fiemap: preallocate ulists for btrfs_check_shared 2019-07-01 13:34:53 +02:00
block-group.c btrfs: fix removal of raid[56|1c34} incompat flags after removing block group 2020-03-20 21:31:32 +01:00
block-group.h btrfs: Move and unexport btrfs_rmap_block 2020-01-23 17:24:34 +01:00
block-rsv.c btrfs: use btrfs_try_granting_tickets in update_global_rsv 2019-09-09 14:59:19 +02:00
block-rsv.h btrfs: migrate the global_block_rsv helpers to block-rsv.c 2019-07-02 12:30:55 +02:00
btrfs_inode.h Btrfs: remove unnecessary delalloc mutex for inodes 2019-11-18 17:51:46 +01:00
check-integrity.c btrfs: remove superfluous BUG_ON() in integrity checks 2020-01-20 16:40:52 +01:00
check-integrity.h
compression.c btrfs: use larger zlib buffer for s390 hardware compression 2020-01-31 10:30:40 -08:00
compression.h btrfs: compression: remove ops pointer from workspace_manager 2019-11-18 12:46:59 +01:00
ctree.c Btrfs: don't iterate mod seq list when putting a tree mod seq 2020-03-23 17:01:23 +01:00
ctree.h Btrfs: fix race between adding and putting tree mod seq elements and nodes 2020-01-31 14:01:20 +01:00
delalloc-space.c Btrfs: remove unnecessary delalloc mutex for inodes 2019-11-18 17:51:46 +01:00
delalloc-space.h btrfs: migrate the delalloc space stuff to it's own home 2019-07-04 17:26:17 +02:00
delayed-inode.c btrfs: use refcount_inc_not_zero in kill_all_nodes 2019-11-18 12:46:51 +01:00
delayed-inode.h
delayed-ref.c Btrfs: fix race between adding and putting tree mod seq elements and nodes 2020-01-31 14:01:20 +01:00
delayed-ref.h btrfs: migrate the delayed refs rsv code 2019-07-04 17:26:17 +02:00
dev-replace.c btrfs: Add overview of device replace 2020-03-23 17:01:23 +01:00
dev-replace.h btrfs: add __pure attribute to functions 2019-11-18 12:46:52 +01:00
dir-item.c btrfs: remove unused parameter fs_info from btrfs_extend_item 2019-04-29 19:02:50 +02:00
discard.c btrfs: add correction to handle -1 edge case in async discard 2020-01-20 16:41:01 +01:00
discard.h btrfs: have multiple discard lists 2020-01-20 16:41:00 +01:00
disk-io.c btrfs: do not check delayed items are empty for single transaction cleanup 2020-02-19 00:36:41 +01:00
disk-io.h btrfs: drop create parameter to btrfs_get_extent() 2020-01-20 16:40:55 +01:00
export.c btrfs: drop unused parameter is_new from btrfs_iget 2019-11-18 12:46:52 +01:00
export.h
extent_io.c btrfs: drop the -EBUSY case in __extent_writepage_io 2020-01-31 14:02:11 +01:00
extent_io.h btrfs: drop create parameter to btrfs_get_extent() 2020-01-20 16:40:55 +01:00
extent_map.c Btrfs: fix race between using extent maps and merging them 2020-02-12 17:16:46 +01:00
extent_map.h btrfs: remove extent_map::bdev 2019-11-18 23:43:44 +01:00
extent-io-tree.h btrfs: move the failrec tree stuff into extent-io-tree.h 2019-11-18 12:46:47 +01:00
extent-tree.c btrfs: handle logged extent failure properly 2020-02-19 00:39:08 +01:00
file-item.c btrfs: safely advance counter when looking up bio csums 2020-01-20 16:41:01 +01:00
file.c btrfs: drop create parameter to btrfs_get_extent() 2020-01-20 16:40:55 +01:00
free-space-cache.c btrfs: ensure removal of discardable_* in free_bitmap() 2020-01-20 16:41:01 +01:00
free-space-cache.h btrfs: have multiple discard lists 2020-01-20 16:41:00 +01:00
free-space-tree.c btrfs: rename btrfs_block_group_cache 2019-11-18 17:51:51 +01:00
free-space-tree.h btrfs: rename btrfs_block_group_cache 2019-11-18 17:51:51 +01:00
inode-item.c btrfs: Make btrfs_find_name_in_ext_backref return struct btrfs_inode_extref 2019-09-09 14:59:16 +02:00
inode-map.c btrfs: keep track of which extents have been discarded 2020-01-20 16:40:57 +01:00
inode-map.h
inode.c btrfs: fix log context list corruption after rename whiteout error 2020-03-13 22:15:09 +01:00
ioctl.c fs-dedupe-last-block-tag 2020-01-28 15:18:23 -08:00
Kconfig btrfs: add Kconfig dependency for BLAKE2B 2019-12-09 17:56:06 +01:00
locking.c btrfs: document extent buffer locking 2019-11-18 17:51:50 +01:00
locking.h btrfs: move btrfs_unlock_up_safe to other locking functions 2019-11-18 12:46:49 +01:00
lzo.c btrfs: compression: inline free_workspace 2019-11-18 12:46:59 +01:00
Makefile btrfs: add the beginning of async discard, discard workqueue 2020-01-20 16:40:57 +01:00
misc.h btrfs: add 64bit safe helper for power of two checks 2019-11-18 12:46:50 +01:00
ordered-data.c Btrfs: fix btrfs_wait_ordered_range() so that it waits for all ordered extents 2020-02-19 00:39:08 +01:00
ordered-data.h btrfs: make btrfs_ordered_extent naming consistent with btrfs_file_extent_item 2020-01-20 16:40:54 +01:00
orphan.c
print-tree.c btrfs: Remove unneeded semicolon 2020-01-20 16:40:55 +01:00
print-tree.h
props.c btrfs: props: remove unnecessary hash_init() 2019-11-18 12:46:55 +01:00
props.h btrfs: delete unused function btrfs_set_prop_trans 2019-04-29 19:02:54 +02:00
qgroup.c btrfs: destroy qgroup extent records on transaction abort 2020-02-19 00:35:54 +01:00
qgroup.h btrfs: destroy qgroup extent records on transaction abort 2020-02-19 00:35:54 +01:00
raid56.c btrfs: remove pointless local variable in lock_stripe_add() 2019-11-18 12:47:00 +01:00
raid56.h btrfs: constify map parameter for nr_parity_stripes and nr_data_stripes 2019-07-01 13:34:58 +02:00
rcu-string.h
reada.c btrfs: rename btrfs_block_group_cache 2019-11-18 17:51:51 +01:00
ref-verify.c btrfs: ref-verify: fix memory leaks 2020-02-12 17:16:31 +01:00
ref-verify.h btrfs: ref-verify: Use btrfs_ref to refactor btrfs_ref_tree_mod() 2019-04-29 19:02:49 +02:00
relocation.c btrfs: relocation: Add introduction of how relocation works 2020-03-23 17:01:23 +01:00
root-tree.c btrfs: do not delete mismatched root refs 2020-01-08 14:44:24 +01:00
scrub.c for-5.6-tag 2020-01-28 14:53:31 -08:00
send.c Btrfs: send, fix emission of invalid clone operations within the same file 2020-01-31 14:02:19 +01:00
send.h
space-info.c btrfs: take overcommit into account in inc_block_group_ro 2020-01-31 14:02:01 +01:00
space-info.h btrfs: take overcommit into account in inc_block_group_ro 2020-01-31 14:02:01 +01:00
struct-funcs.c btrfs: tie extent buffer and it's token together 2019-09-09 14:59:16 +02:00
super.c btrfs: log message when rw remount is attempted with unclean tree-log 2020-02-12 17:17:00 +01:00
sysfs.c btrfs: sysfs, move device id directories to UUID/devinfo 2020-02-12 18:28:22 +01:00
sysfs.h btrfs: sysfs, add devid/dev_state kobject and device attributes 2020-01-23 17:24:36 +01:00
transaction.c btrfs: destroy qgroup extent records on transaction abort 2020-02-19 00:35:54 +01:00
transaction.h btrfs: Rename btrfs_join_transaction_nolock 2019-11-18 12:46:54 +01:00
tree-checker.c btrfs: tree-checker: Verify location key for DIR_ITEM/DIR_INDEX 2020-01-20 16:40:56 +01:00
tree-checker.h btrfs: get fs_info from eb in btrfs_check_chunk_valid 2019-04-29 19:02:39 +02:00
tree-defrag.c btrfs: open code now trivial btrfs_set_lock_blocking 2019-02-25 14:13:27 +01:00
tree-log.c Btrfs: fix infinite loop during fsync after rename operations 2020-01-23 17:24:37 +01:00
tree-log.h btrfs: get fs_info from trans in btrfs_set_log_full_commit 2019-04-29 19:02:41 +02:00
ulist.c
ulist.h
uuid-tree.c btrfs: handle ENOENT in btrfs_uuid_tree_iterate 2019-12-13 14:10:45 +01:00
volumes.c btrfs: Fix split-brain handling when changing FSID to metadata uuid 2020-01-23 17:24:39 +01:00
volumes.h for-5.6-rc1-tag 2020-02-16 11:43:45 -08:00
xattr.c Btrfs: fix failure to persist compression property xattr deletion on fsync 2019-06-17 16:37:17 +02:00
xattr.h btrfs: cleanup btrfs_setxattr_trans and drop transaction parameter 2019-04-29 19:02:44 +02:00
zlib.c btrfs: use larger zlib buffer for s390 hardware compression 2020-01-31 10:30:40 -08:00
zstd.c btrfs: compression: inline free_workspace 2019-11-18 12:46:59 +01:00