linux.git/fs/btrfs/backref.c, branch v5.19

btrfs: unify the error handling pattern for read_tree_block()

2022-03-14T12:13:53+00:00

We had an error handling pattern for read_tree_block() like this:

	eb = read_tree_block();
	if (IS_ERR(eb)) {
		/*
		 * Handling error here
		 * Normally ended up with return or goto out.
		 */
	} else if (!extent_buffer_uptodate(eb)) {
		/*
		 * Different error handling here
		 * Normally also ended up with return or goto out;
		 */
	}

This is fine, but if we want to add extra check for each
read_tree_block(), the existing if-else-if is not that expandable and
will take reader some seconds to figure out there is no extra branch.

Here we change it to a more common way, without the extra else:

	eb = read_tree_block();
	if (IS_ERR(eb)) {
		/*
		 * Handling error here
		 */
		return eb or goto out;
	}
	if (!extent_buffer_uptodate(eb)) {
		/*
		 * Different error handling here
		 */
		return eb or goto out;
	}

This also removes some oddball call sites which uses some creative way
to check error.

Signed-off-by: Qu Wenruo 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba

btrfs: stop accessing ->extent_root directly

2022-01-03T14:09:49+00:00

When we start having multiple extent roots we'll need to use a helper to
get to the correct extent_root.  Rename fs_info->extent_root to
_extent_root and convert all of the users of the extent root to using
the btrfs_extent_root() helper.  This will allow us to easily clean up
the remaining direct accesses in the future.

Signed-off-by: Josef Bacik 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba

btrfs: don't use extent_root in iterate_extent_inodes

2022-01-03T14:09:48+00:00

We are going to have many extent_roots soon, and we don't need a root
here necessarily as we're not modifying anything, we're just getting the
trans handle so we can have an accurate view of references, so use the
tree_root here.

Signed-off-by: Josef Bacik 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba

btrfs: remove BUG_ON(!eie) in find_parent_nodes

2022-01-03T14:09:47+00:00

If we're looking for leafs that point to a data extent we want to record
the extent items that point at our bytenr.  At this point we have the
reference and we know for a fact that this leaf should have a reference
to our bytenr.  However if there's some sort of corruption we may not
find any references to our leaf, and thus could end up with eie == NULL.
Replace this BUG_ON() with an ASSERT() and then return -EUCLEAN for the
mortals.

Signed-off-by: Josef Bacik 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba

btrfs: remove BUG_ON() in find_parent_nodes()

2022-01-03T14:09:47+00:00

We search for an extent entry with .offset = -1, which shouldn't be a
thing, but corruption happens.  Add an ASSERT() for the developers,
return -EUCLEAN for mortals.

Signed-off-by: Josef Bacik 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba

btrfs: remove SANITY_TESTS check form find_parent_nodes

2022-01-03T14:09:47+00:00

We define __TRANS_DUMMY always, so this extra ifdef stuff is not needed.

Signed-off-by: Josef Bacik 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba

btrfs: move comment in find_parent_nodes()

2022-01-03T14:09:47+00:00

This comment was much closer to the related code when it was originally
added, but has slowly migrated north far from its ancestral lands.  Move
it back down with its people.

Signed-off-by: Josef Bacik 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba

btrfs: pass the root to add_keyed_refs

2022-01-03T14:09:47+00:00

We pass in the path, but use btrfs_next_item() using the root we
searched with.  Pass the root down to add_keyed_refs() instead of the
fs_info so we can continue to use the same root we searched with.

Signed-off-by: Josef Bacik 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba

btrfs: drop the _nr from the item helpers

2022-01-03T14:09:43+00:00

Now that all call sites are using the slot number to modify item values,
rename the SETGET helpers to raw_item_*(), and then rework the _nr()
helpers to be the btrfs_item_*() btrfs_set_item_*() helpers, and then
rename all of the callers to the new helpers.

Signed-off-by: Josef Bacik 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba

btrfs: use btrfs_item_size_nr/btrfs_item_offset_nr everywhere

2022-01-03T14:09:42+00:00

We have this pattern in a lot of places

	item = btrfs_item_nr(slot);
	btrfs_item_size(leaf, item);

when we could simply use

	btrfs_item_size(leaf, slot);

Fix all callers of btrfs_item_size() and btrfs_item_offset() to use the
_nr variation of the helpers.

Reviewed-by: Qu Wenruo 
Signed-off-by: Josef Bacik 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba