From: Wang Xiaoguang <wangxg.f...@cn.fujitsu.com>
Introduce static function inmem_add() to add hash into in-memory tree.
And now we can implement the btrfs_dedup_add() interface.
Signed-off-by: Wang Xiaoguang <wangxg.f...@cn.fujitsu.com>
---
fs/btrfs/dedup.c | 116 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 116 insertions(+)
diff --git a/fs/btrfs/dedup.c b/fs/btrfs/dedup.c
index c1fadff..cafbce1 100644
--- a/fs/btrfs/dedup.c
+++ b/fs/btrfs/dedup.c
@@ -94,3 +94,119 @@ out:
}
return ret;
}
+
+static int inmem_insert_hash(struct rb_root *root,
+ struct btrfs_dedup_hash *hash, int hash_len)
+{
+ struct rb_node **p = &root->rb_node;
+ struct rb_node *parent = NULL;
+ struct btrfs_dedup_hash *entry = NULL;
+
+ while (*p) {
+ parent = *p;
+ entry = rb_entry(parent, struct btrfs_dedup_hash,
+ hash_node);
+ if (memcmp(hash->hash, entry->hash, hash_len) < 0)
+ p = &(*p)->rb_left;
+ else if (memcmp(hash->hash, entry->hash, hash_len) > 0)
+ p = &(*p)->rb_right;
+ else
+ return 1;
+ }
+ rb_link_node(&hash->hash_node, parent, p);
+ rb_insert_color(&hash->hash_node, root);
+ return 0;
+}
+
+static int inmem_insert_bytenr(struct rb_root *root,
+ struct btrfs_dedup_hash *hash)
+{
+ struct rb_node **p = &root->rb_node;
+ struct rb_node *parent = NULL;
+ struct btrfs_dedup_hash *entry = NULL;
+
+ while (*p) {
+ parent = *p;
+ entry = rb_entry(parent, struct btrfs_dedup_hash, bytenr_node);
+ if (hash->bytenr < entry->bytenr)
+ p = &(*p)->rb_left;
+ else if (hash->bytenr > entry->bytenr)
+ p = &(*p)->rb_right;
+ else
+ return 1;
+ }
+ rb_link_node(&hash->bytenr_node, parent, p);
+ rb_insert_color(&hash->bytenr_node, root);
+ return 0;
+}
+
+static void __inmem_del(struct btrfs_dedup_info *dedup_info,
+ struct btrfs_dedup_hash *hash)
+{
+ list_del(&hash->lru_list);
+ rb_erase(&hash->hash_node, &dedup_info->hash_root);
+ rb_erase(&hash->bytenr_node, &dedup_info->bytenr_root);
+
+ if (!WARN_ON(dedup_info->current_nr == 0))
+ dedup_info->current_nr--;
+
+ kfree(hash);
+}
+
+/*
+ * Insert a hash into in-memory dedup tree
+ * Will remove exceeding last recent use hash.
+ *
+ * If the hash mathced with existing one, we won't insert it, to
+ * save memory
+ */
+static int inmem_add(struct btrfs_dedup_info *dedup_info,
+ struct btrfs_dedup_hash *hash)
+{
+ int ret = 0;
+ u16 type = dedup_info->hash_type;
+
+ spin_lock(&dedup_info->lock);
+ ret = inmem_insert_hash(&dedup_info->hash_root, hash,
+ btrfs_dedup_sizes[type]);
+ if (ret > 0) {
+ /* Same hash already in tree, don't insert */
+ kfree(hash);
+ ret = 0;
+ goto out;
+ }
+
+ inmem_insert_bytenr(&dedup_info->bytenr_root, hash);
+
+ list_add(&hash->lru_list, &dedup_info->lru_list);
+ dedup_info->current_nr++;
+
+ /* Remove the last dedup hash if we exceed limit */
+ while (dedup_info->current_nr > dedup_info->limit_nr) {
+ struct btrfs_dedup_hash *last;
+
+ last = list_entry(dedup_info->lru_list.prev,
+ struct btrfs_dedup_hash, lru_list);
+ __inmem_del(dedup_info, last);
+ }
+out:
+ spin_unlock(&dedup_info->lock);
+ return 0;
+}
+
+int btrfs_dedup_add(struct btrfs_trans_handle *trans, struct btrfs_root *root,
+ struct btrfs_dedup_hash *hash)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_dedup_info *dedup_info = fs_info->dedup_info;
+
+ if (!dedup_info || !hash)
+ return 0;
+
+ if (WARN_ON(hash->bytenr == 0))
+ return -EINVAL;
+
+ if (dedup_info->backend == BTRFS_DEDUP_BACKEND_INMEMORY)
+ return inmem_add(dedup_info, hash);
+ return -EINVAL;
+}
--
2.6.4
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
