The operations consist of finding matched items, adding new items and
removing items.

Signed-off-by: Liu Bo <bo.li....@oracle.com>
---
 fs/btrfs/ctree.h     |   9 +++
 fs/btrfs/file-item.c | 210 +++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 219 insertions(+)

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 54c29d2..7b14e2e 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3760,6 +3760,15 @@ int btrfs_csum_one_bio(struct btrfs_root *root, struct 
inode *inode,
 int btrfs_lookup_csums_range(struct btrfs_root *root, u64 start, u64 end,
                             struct list_head *list, int search_commit);
 
+int noinline_for_stack
+btrfs_find_dedup_extent(struct btrfs_root *root, struct btrfs_dedup_hash 
*hash);
+int noinline_for_stack
+btrfs_insert_dedup_extent(struct btrfs_trans_handle *trans,
+                         struct btrfs_root *root,
+                         struct btrfs_dedup_hash *hash);
+int noinline_for_stack
+btrfs_free_dedup_extent(struct btrfs_trans_handle *trans,
+                       struct btrfs_root *root, u64 hash, u64 bytenr);
 /* inode.c */
 struct btrfs_delalloc_work {
        struct inode *inode;
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 9d84658..068112c 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -884,3 +884,213 @@ out:
 fail_unlock:
        goto out;
 }
+
+/* 1 means we find one, 0 means we dont. */
+int noinline_for_stack
+btrfs_find_dedup_extent(struct btrfs_root *root, struct btrfs_dedup_hash *hash)
+{
+       struct btrfs_key key;
+       struct btrfs_path *path;
+       struct extent_buffer *leaf;
+       struct btrfs_root *dedup_root;
+       struct btrfs_dedup_item *item;
+       u64 hash_value;
+       u64 length;
+       u64 dedup_size;
+       int compression;
+       int found = 0;
+       int index;
+       int ret;
+
+       if (!hash) {
+               WARN_ON(1);
+               return 0;
+       }
+       if (!root->fs_info->dedup_root) {
+               WARN(1, KERN_INFO "dedup not enabled\n");
+               return 0;
+       }
+       dedup_root = root->fs_info->dedup_root;
+
+       path = btrfs_alloc_path();
+       if (!path)
+               return 0;
+
+       /*
+        * For SHA256 dedup algorithm, we store the last 64bit as the
+        * key.objectid, and the rest in the tree item.
+        */
+       index = btrfs_dedup_lens[hash->type] - 1;
+       dedup_size = btrfs_dedup_sizes[hash->type] - sizeof(u64);
+
+       hash_value = hash->hash[index];
+
+       key.objectid = hash_value;
+       key.offset = (u64)-1;
+       btrfs_set_key_type(&key, BTRFS_DEDUP_ITEM_KEY);
+
+       ret = btrfs_search_slot(NULL, dedup_root, &key, path, 0, 0);
+       if (ret < 0)
+               goto out;
+       if (ret == 0) {
+               WARN_ON(1);
+               goto out;
+       }
+
+prev_slot:
+       /* this will do match checks. */
+       ret = btrfs_previous_item(dedup_root, path, hash_value,
+                                 BTRFS_DEDUP_ITEM_KEY);
+       if (ret)
+               goto out;
+
+       leaf = path->nodes[0];
+       btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+       if (key.objectid != hash_value)
+               goto out;
+
+       item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dedup_item);
+       /* disk length of dedup range */
+       length = btrfs_dedup_len(leaf, item);
+
+       compression = btrfs_dedup_compression(leaf, item);
+       if (compression > BTRFS_COMPRESS_TYPES) {
+               WARN_ON(1);
+               goto out;
+       }
+
+       if (btrfs_dedup_type(leaf, item) != hash->type)
+               goto prev_slot;
+
+       if (memcmp_extent_buffer(leaf, hash->hash, (unsigned long)(item + 1),
+                                dedup_size)) {
+               pr_info("goto prev\n");
+               goto prev_slot;
+       }
+
+       hash->bytenr = key.offset;
+       hash->num_bytes = length;
+       hash->compression = compression;
+       found = 1;
+out:
+       btrfs_free_path(path);
+       return found;
+}
+
+int noinline_for_stack
+btrfs_insert_dedup_extent(struct btrfs_trans_handle *trans,
+                         struct btrfs_root *root,
+                         struct btrfs_dedup_hash *hash)
+{
+       struct btrfs_key key;
+       struct btrfs_path *path;
+       struct extent_buffer *leaf;
+       struct btrfs_root *dedup_root;
+       struct btrfs_dedup_item *dedup_item;
+       u64 ins_size;
+       u64 dedup_size;
+       int index;
+       int ret;
+
+       if (!hash) {
+               WARN_ON(1);
+               return 0;
+       }
+
+       WARN_ON(hash->num_bytes > root->fs_info->dedup_bs);
+
+       if (!root->fs_info->dedup_root) {
+               WARN(1, KERN_INFO "dedup not enabled\n");
+               return 0;
+       }
+       dedup_root = root->fs_info->dedup_root;
+
+       path = btrfs_alloc_path();
+       if (!path)
+               return -ENOMEM;
+
+       /*
+        * For SHA256 dedup algorithm, we store the last 64bit as the
+        * key.objectid, and the rest in the tree item.
+        */
+       index = btrfs_dedup_lens[hash->type] - 1;
+       dedup_size = btrfs_dedup_sizes[hash->type] - sizeof(u64);
+
+       ins_size = sizeof(*dedup_item) + dedup_size;
+
+       key.objectid = hash->hash[index];
+       key.offset = hash->bytenr;
+       btrfs_set_key_type(&key, BTRFS_DEDUP_ITEM_KEY);
+
+       path->leave_spinning = 1;
+       ret = btrfs_insert_empty_item(trans, dedup_root, path, &key, ins_size);
+       if (ret < 0)
+               goto out;
+       leaf = path->nodes[0];
+
+       dedup_item = btrfs_item_ptr(leaf, path->slots[0],
+                                   struct btrfs_dedup_item);
+       /* disk length of dedup range */
+       btrfs_set_dedup_len(leaf, dedup_item, hash->num_bytes);
+       btrfs_set_dedup_compression(leaf, dedup_item, hash->compression);
+       btrfs_set_dedup_encryption(leaf, dedup_item, 0);
+       btrfs_set_dedup_other_encoding(leaf, dedup_item, 0);
+       btrfs_set_dedup_type(leaf, dedup_item, hash->type);
+
+       write_extent_buffer(leaf, hash->hash, (unsigned long)(dedup_item + 1),
+                           dedup_size);
+
+       btrfs_mark_buffer_dirty(leaf);
+out:
+       WARN_ON(ret == -EEXIST);
+       btrfs_free_path(path);
+       return ret;
+}
+
+int noinline_for_stack
+btrfs_free_dedup_extent(struct btrfs_trans_handle *trans,
+                       struct btrfs_root *root, u64 hash, u64 bytenr)
+{
+       struct btrfs_key key;
+       struct btrfs_path *path;
+       struct extent_buffer *leaf;
+       struct btrfs_root *dedup_root;
+       int ret = 0;
+
+       if (!root->fs_info->dedup_root)
+               return 0;
+
+       dedup_root = root->fs_info->dedup_root;
+
+       path = btrfs_alloc_path();
+       if (!path)
+               return ret;
+
+       key.objectid = hash;
+       key.offset = bytenr;
+       btrfs_set_key_type(&key, BTRFS_DEDUP_ITEM_KEY);
+
+       ret = btrfs_search_slot(trans, dedup_root, &key, path, -1, 1);
+       if (ret < 0)
+               goto out;
+       if (ret) {
+               WARN_ON(1);
+               ret = -ENOENT;
+               goto out;
+       }
+
+       leaf = path->nodes[0];
+
+       ret = -ENOENT;
+       btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+       if (btrfs_key_type(&key) != BTRFS_DEDUP_ITEM_KEY)
+               goto out;
+       if (key.objectid != hash || key.offset != bytenr)
+               goto out;
+
+       ret = btrfs_del_item(trans, dedup_root, path);
+       WARN_ON(ret);
+out:
+       btrfs_free_path(path);
+       return ret;
+}
-- 
1.8.2.1

--
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

Reply via email to