[PATCH 07/10] btrfs: relocation: Specify essential members for alloc_backref_node()

Qu Wenruo
2020-02-26T05:57:16Z

Bytenr and level are essential parameters for backref_node, thus it
makes sense to initial them at alloc time.

Signed-off-by: Qu Wenruo <wqu@suse.com>
---
fs/btrfs/relocation.c | 25 ++++++++++++-------------
1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 660f4884fed4..f072d075a202 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -274,10 +274,12 @@ static void backref_cache_cleanup(struct backref_cache *cache)
ASSERT(!cache->nr_edges);
}

-static struct backref_node *alloc_backref_node(struct backref_cache *cache)
+static struct backref_node *alloc_backref_node(struct backref_cache *cache,
+ u64 bytenr, int level)
{
struct backref_node *node;

+ ASSERT(level >= 0 && level < BTRFS_MAX_LEVEL);
node = kzalloc(sizeof(*node), GFP_NOFS);
if (node) {
INIT_LIST_HEAD(&node->list);
@@ -285,6 +287,9 @@ static struct backref_node *alloc_backref_node(struct backref_cache *cache)
INIT_LIST_HEAD(&node->lower);
RB_CLEAR_NODE(&node->rb_node);
cache->nr_nodes++;
+
+ node->level = level;
+ node->bytenr = bytenr;
}
return node;
}
@@ -701,13 +706,12 @@ static int handle_one_tree_backref(struct reloc_control *rc,
rb_node = tree_search(&cache->rb_root, ref_key->offset);
if (!rb_node) {
/* Parent node not yet cached */
- upper = alloc_backref_node(cache);
+ upper = alloc_backref_node(cache, ref_key->offset,
+ cur->level + 1);
if (!upper) {
free_backref_edge(cache, edge);
return -ENOMEM;
}
- upper->bytenr = ref_key->offset;
- upper->level = cur->level + 1;

/*
* backrefs for the upper level block isn't
@@ -788,15 +792,14 @@ static int handle_one_tree_backref(struct reloc_control *rc,
eb = path->nodes[level];
rb_node = tree_search(&cache->rb_root, eb->start);
if (!rb_node) {
- upper = alloc_backref_node(cache);
+ upper = alloc_backref_node(cache, eb->start,
+ lower->level + 1);
if (!upper) {
free_backref_edge(cache, edge);
ret = -ENOMEM;
goto out;
}
- upper->bytenr = eb->start;
upper->owner = btrfs_header_owner(eb);
- upper->level = lower->level + 1;
if (!test_bit(BTRFS_ROOT_REF_COWS,
&root->state))
upper->cowonly = 1;
@@ -888,14 +891,12 @@ struct backref_node *build_backref_tree(struct reloc_control *rc,
}
path->reada = READA_FORWARD;

- node = alloc_backref_node(cache);
+ node = alloc_backref_node(cache, bytenr, level);
if (!node) {
err = -ENOMEM;
goto out;
}

- node->bytenr = bytenr;
- node->level = level;
node->lowest = 1;
cur = node;
again:
@@ -1206,12 +1207,10 @@ static int clone_backref_node(struct btrfs_trans_handle *trans,
if (!node)
return 0;

- new_node = alloc_backref_node(cache);
+ new_node = alloc_backref_node(cache, dest->node->start, node->level);
if (!new_node)
return -ENOMEM;

- new_node->bytenr = dest->node->start;
- new_node->level = node->level;
new_node->lowest = node->lowest;
new_node->checked = 1;
new_node->root = dest;
--
2.25.1