From: Mark Fasheh <mfas...@suse.de>
build_backref_tree() is walking extent refs in what is an otherwise self
contained chunk of code. We can shrink the total number of lines in
build_backref_tree() *and* make it more readable by moving that walk into
its own subroutine.
Signed-off-by: Mark Fasheh <mfas...@suse.de>
---
fs/btrfs/backref-cache.c | 110 +++++++++++++++++++++++----------------
1 file changed, 65 insertions(+), 45 deletions(-)
diff --git a/fs/btrfs/backref-cache.c b/fs/btrfs/backref-cache.c
index d0f6530f23b8..ff0d49ca6e26 100644
--- a/fs/btrfs/backref-cache.c
+++ b/fs/btrfs/backref-cache.c
@@ -336,6 +336,61 @@ int find_inline_backref(struct extent_buffer *leaf, int
slot,
return 0;
}
+#define SEARCH_COMPLETE 1
+#define SEARCH_NEXT 2
+static int find_next_ref(struct btrfs_root *extent_root, u64 cur_bytenr,
+ struct btrfs_path *path, unsigned long *ptr,
+ unsigned long *end, struct btrfs_key *key, bool exist)
+{
+ struct extent_buffer *eb = path->nodes[0];
+ int ret;
+
+ if (*ptr >= *end) {
+ if (path->slots[0] >= btrfs_header_nritems(eb)) {
+ ret = btrfs_next_leaf(extent_root, path);
+ if (ret < 0)
+ goto out;
+ if (ret > 0)
+ return SEARCH_COMPLETE;
+ eb = path->nodes[0];
+ }
+
+ btrfs_item_key_to_cpu(eb, key, path->slots[0]);
+ if (key->objectid != cur_bytenr) {
+ WARN_ON(exist);
+ return SEARCH_COMPLETE;
+ }
+
+ if (key->type == BTRFS_EXTENT_ITEM_KEY ||
+ key->type == BTRFS_METADATA_ITEM_KEY) {
+ ret = find_inline_backref(eb, path->slots[0],
+ ptr, end);
+ if (ret)
+ return SEARCH_NEXT;
+ }
+ }
+
+ if (*ptr < *end) {
+ /* update key for inline back ref */
+ struct btrfs_extent_inline_ref *iref;
+ int type;
+ iref = (struct btrfs_extent_inline_ref *)(*ptr);
+ type = btrfs_get_extent_inline_ref_type(eb, iref,
+ BTRFS_REF_TYPE_BLOCK);
+ if (type == BTRFS_REF_TYPE_INVALID) {
+ ret = -EUCLEAN;
+ goto out;
+ }
+ key->type = type;
+ key->offset = btrfs_extent_inline_ref_offset(eb, iref);
+
+ WARN_ON(key->type != BTRFS_TREE_BLOCK_REF_KEY &&
+ key->type != BTRFS_SHARED_BLOCK_REF_KEY);
+ }
+ ret = 0;
+out:
+ return ret;
+}
/*
* build backref tree for a given tree block. root of the backref tree
@@ -439,52 +494,17 @@ struct backref_node *build_backref_tree(struct
reloc_control *rc,
while (1) {
cond_resched();
- eb = path1->nodes[0];
-
- if (ptr >= end) {
- if (path1->slots[0] >= btrfs_header_nritems(eb)) {
- ret = btrfs_next_leaf(rc->extent_root, path1);
- if (ret < 0) {
- err = ret;
- goto out;
- }
- if (ret > 0)
- break;
- eb = path1->nodes[0];
- }
-
- btrfs_item_key_to_cpu(eb, &key, path1->slots[0]);
- if (key.objectid != cur->bytenr) {
- WARN_ON(exist);
- break;
- }
-
- if (key.type == BTRFS_EXTENT_ITEM_KEY ||
- key.type == BTRFS_METADATA_ITEM_KEY) {
- ret = find_inline_backref(eb, path1->slots[0],
- &ptr, &end);
- if (ret)
- goto next;
- }
- }
-
- if (ptr < end) {
- /* update key for inline back ref */
- struct btrfs_extent_inline_ref *iref;
- int type;
- iref = (struct btrfs_extent_inline_ref *)ptr;
- type = btrfs_get_extent_inline_ref_type(eb, iref,
- BTRFS_REF_TYPE_BLOCK);
- if (type == BTRFS_REF_TYPE_INVALID) {
- err = -EUCLEAN;
- goto out;
- }
- key.type = type;
- key.offset = btrfs_extent_inline_ref_offset(eb, iref);
-
- WARN_ON(key.type != BTRFS_TREE_BLOCK_REF_KEY &&
- key.type != BTRFS_SHARED_BLOCK_REF_KEY);
+ ret = find_next_ref(rc->extent_root, cur->bytenr, path1, &ptr,
+ &end, &key, exist != NULL);
+ if (ret < 0) {
+ err = ret;
+ goto out;
}
+ eb = path1->nodes[0];
+ if (ret == SEARCH_COMPLETE)
+ break;
+ else if (ret == SEARCH_NEXT)
+ goto next;
/*
* Parent node found and matches current inline ref, no need to
--
2.22.1
