linux/fs/btrfs
Qu Wenruo 6275193ef1 btrfs: refactor btrfs_lookup_bio_sums to handle out-of-order bvecs
Refactor btrfs_lookup_bio_sums() by:

- Remove the @file_offset parameter
  There are two factors making the @file_offset parameter useless:

  * For csum lookup in csum tree, file offset makes no sense
    We only need disk_bytenr, which is unrelated to file_offset

  * page_offset (file offset) of each bvec is not contiguous.
    Pages can be added to the same bio as long as their on-disk bytenr
    is contiguous, meaning we could have pages at different file offsets
    in the same bio.

  Thus passing file_offset makes no sense any more.
  The only user of file_offset is for data reloc inode, we will use
  a new function, search_file_offset_in_bio(), to handle it.

- Extract the csum tree lookup into search_csum_tree()
  The new function will handle the csum search in csum tree.
  The return value is the same as btrfs_find_ordered_sum(), returning
  the number of found sectors which have checksum.

- Change how we do the main loop
  The only needed info from bio is:
  * the on-disk bytenr
  * the length

  After extracting the above info, we can do the search without bio
  at all, which makes the main loop much simpler:

	for (cur_disk_bytenr = orig_disk_bytenr;
	     cur_disk_bytenr < orig_disk_bytenr + orig_len;
	     cur_disk_bytenr += count * sectorsize) {

		/* Lookup csum tree */
		count = search_csum_tree(fs_info, path, cur_disk_bytenr,
					 search_len, csum_dst);
		if (!count) {
			/* Csum hole handling */
		}
	}

- Use single variable as the source to calculate all other offsets
  Instead of all different type of variables, we use only one main
  variable, cur_disk_bytenr, which represents the current disk bytenr.

  All involved values can be calculated from that variable, and
  all those variable will only be visible in the inner loop.

The above refactoring makes btrfs_lookup_bio_sums() way more robust than
it used to be, especially related to the file offset lookup.  Now
file_offset lookup is only related to data reloc inode, otherwise we
don't need to bother file_offset at all.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2020-12-09 19:16:11 +01:00
..
tests btrfs: remove recalc_thresholds from free space ops 2020-12-09 19:16:06 +01:00
acl.c
async-thread.c Btrfs: fix crash during unmount due to race with delayed inode workers 2020-03-23 17:01:51 +01:00
async-thread.h Btrfs: fix crash during unmount due to race with delayed inode workers 2020-03-23 17:01:51 +01:00
backref.c btrfs: pass root owner to read_tree_block 2020-12-08 15:54:07 +01:00
backref.h btrfs: rename BTRFS_ROOT_REF_COWS to BTRFS_ROOT_SHAREABLE 2020-05-25 11:25:35 +02:00
block-group.c btrfs: skip space_cache v1 setup when not using it 2020-12-09 19:16:09 +01:00
block-group.h btrfs: load free space cache asynchronously 2020-12-08 15:54:03 +01:00
block-rsv.c btrfs: introduce mount option rescue=ignorebadroots 2020-12-08 15:53:41 +01:00
block-rsv.h btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
btrfs_inode.h btrfs: skip unnecessary searches for xattrs when logging an inode 2020-12-08 15:54:12 +01:00
check-integrity.c btrfs: drop casts of bio bi_sector 2020-12-09 19:16:05 +01:00
check-integrity.h btrfs: remove btrfsic_submit_bh() 2020-03-23 17:01:39 +01:00
compression.c btrfs: refactor btrfs_lookup_bio_sums to handle out-of-order bvecs 2020-12-09 19:16:11 +01:00
compression.h btrfs: compression: move declarations to header 2020-10-07 12:06:55 +02:00
ctree.c btrfs: handle sectorsize < PAGE_SIZE case for extent buffer accessors 2020-12-09 19:16:10 +01:00
ctree.h btrfs: refactor btrfs_lookup_bio_sums to handle out-of-order bvecs 2020-12-09 19:16:11 +01:00
delalloc-space.c btrfs: add btrfs_reserve_data_bytes and use it 2020-10-07 12:06:52 +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: make btrfs_delayed_update_inode take btrfs_inode 2020-12-08 15:54:10 +01:00
delayed-inode.h btrfs: make btrfs_delayed_update_inode take btrfs_inode 2020-12-08 15:54:10 +01:00
delayed-ref.c btrfs: Remove __ prefix from btrfs_block_rsv_release 2020-03-23 17:01:55 +01:00
delayed-ref.h
dev-replace.c btrfs: check and enable ZONED mode 2020-12-09 19:16:03 +01:00
dev-replace.h
dir-item.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
discard.c btrfs: don't miss async discards after scheduled work override 2020-12-08 15:54:05 +01:00
discard.h btrfs: cleanup btrfs_discard_update_discardable usage 2020-12-08 15:54:02 +01:00
disk-io.c btrfs: rename bio_offset of extent_submit_bio_start_t to dio_file_offset 2020-12-09 19:16:09 +01:00
disk-io.h btrfs: rename bio_offset of extent_submit_bio_start_t to dio_file_offset 2020-12-09 19:16:09 +01:00
export.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
export.h btrfs: export helpers for subvolume name/id resolution 2020-03-23 17:01:42 +01:00
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: set the lockdep class for extent buffers on creation 2020-12-08 15:54:07 +01:00
extent_io.c btrfs: handle sectorsize < PAGE_SIZE case for extent buffer accessors 2020-12-09 19:16:10 +01:00
extent_io.h btrfs: update num_extent_pages to support subpage sized extent buffer 2020-12-09 19:16:10 +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
file-item.c btrfs: refactor btrfs_lookup_bio_sums to handle out-of-order bvecs 2020-12-09 19:16:11 +01:00
file.c btrfs: disable fallocate in ZONED mode 2020-12-09 19:16:04 +01:00
free-space-cache.c btrfs: remove free space items when disabling space cache v1 2020-12-09 19:16:09 +01:00
free-space-cache.h btrfs: remove free space items when disabling space cache v1 2020-12-09 19:16:09 +01:00
free-space-tree.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +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: refactor btrfs_lookup_bio_sums to handle out-of-order bvecs 2020-12-09 19:16:11 +01:00
ioctl.c btrfs: remove inode number cache feature 2020-12-09 19:16:05 +01:00
Kconfig btrfs: switch to iomap for direct IO 2020-10-07 12:06:57 +02:00
locking.c btrfs: remove the recurse parameter from __btrfs_tree_read_lock 2020-12-08 15:54:09 +01:00
locking.h btrfs: remove the recurse parameter from __btrfs_tree_read_lock 2020-12-08 15:54:09 +01:00
lzo.c
Makefile btrfs: remove inode number cache feature 2020-12-09 19:16:05 +01:00
misc.h btrfs: rename tree_entry to rb_simple_node and export it 2020-05-25 11:25:19 +02:00
ordered-data.c btrfs: remove btrfs_find_ordered_sum call from btrfs_lookup_bio_sums 2020-12-09 19:16:10 +01:00
ordered-data.h btrfs: remove btrfs_find_ordered_sum call from btrfs_lookup_bio_sums 2020-12-09 19:16:10 +01:00
orphan.c
print-tree.c btrfs: pass root owner to read_tree_block 2020-12-08 15:54:07 +01:00
print-tree.h btrfs: pretty print leaked root name 2020-10-07 12:12:20 +02:00
props.c btrfs: simplify iget helpers 2020-05-25 11:25:37 +02:00
props.h
qgroup.c btrfs: pass root owner to read_tree_block 2020-12-08 15:54:07 +01:00
qgroup.h btrfs: qgroup: export qgroups in sysfs 2020-07-27 12:55:37 +02:00
raid56.c btrfs: drop casts of bio bi_sector 2020-12-09 19:16:05 +01:00
raid56.h
rcu-string.h btrfs: rcu-string: Replace zero-length array with flexible-array member 2020-03-23 17:01:53 +01:00
reada.c btrfs: pass the owner_root and level to alloc_extent_buffer 2020-12-08 15:54:07 +01:00
ref-verify.c btrfs: use btrfs_read_node_slot in walk_down_tree 2020-12-08 15:54:06 +01:00
ref-verify.h
reflink.c btrfs: make btrfs_cont_expand take btrfs_inode 2020-12-08 15:54:12 +01:00
reflink.h Btrfs: move all reflink implementation code into its own file 2020-03-23 17:01:54 +01:00
relocation.c btrfs: remove inode number cache feature 2020-12-09 19:16:05 +01:00
root-tree.c btrfs: qgroup: fix qgroup meta rsv leak for subvolume operations 2020-10-07 12:12:13 +02:00
scrub.c btrfs: implement log-structured superblock for ZONED mode 2020-12-09 19:16:04 +01:00
send.c btrfs: send: use helpers to access root_item::ctransid 2020-12-08 15:53:51 +01:00
send.h btrfs: send: avoid copying file data 2020-10-07 12:13:17 +02:00
space-info.c btrfs: kill the RCU protection for fs_info->space_info 2020-10-07 12:13:19 +02:00
space-info.h btrfs: add btrfs_reserve_data_bytes and use it 2020-10-07 12:06:52 +02:00
struct-funcs.c btrfs: handle sectorsize < PAGE_SIZE case for extent buffer accessors 2020-12-09 19:16:10 +01:00
super.c btrfs: warn when remount will not change the free space tree 2020-12-09 19:16:08 +01:00
sysfs.c btrfs: introduce ZONED feature flag 2020-12-08 15:54:16 +01:00
sysfs.h btrfs: split and refactor btrfs_sysfs_remove_devices_dir 2020-10-07 12:12:21 +02:00
transaction.c btrfs: keep sb cache_generation consistent with space_cache 2020-12-09 19:16:08 +01:00
transaction.h btrfs: return bool from btrfs_should_end_transaction 2020-12-08 15:54:16 +01:00
tree-checker.c btrfs: tree-checker: annotate all error branches as unlikely 2020-12-08 15:54:15 +01:00
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: do not block inode logging for so long during transaction commit 2020-12-09 19:16:07 +01:00
tree-log.h btrfs: make fast fsyncs wait only for writeback 2020-10-07 12:06:56 +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: drop casts of bio bi_sector 2020-12-09 19:16:05 +01:00
volumes.h btrfs: get zone information of zoned block devices 2020-12-09 19:15:57 +01:00
xattr.c btrfs: skip unnecessary searches for xattrs when logging an inode 2020-12-08 15:54:12 +01:00
xattr.h
zlib.c btrfs: use larger zlib buffer for s390 hardware compression 2020-01-31 10:30:40 -08:00
zoned.c btrfs: implement log-structured superblock for ZONED mode 2020-12-09 19:16:04 +01:00
zoned.h btrfs: implement log-structured superblock for ZONED mode 2020-12-09 19:16:04 +01:00
zstd.c