diff options
Diffstat (limited to 'dir-item.c')
| -rw-r--r-- | dir-item.c | 100 |
1 files changed, 100 insertions, 0 deletions
@@ -16,6 +16,7 @@ * Boston, MA 021110-1307, USA. */ +#include <linux/limits.h> #include "ctree.h" #include "disk-io.h" #include "hash.h" @@ -219,6 +220,97 @@ struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, return btrfs_match_dir_item_name(root, path, name, name_len); } +struct btrfs_dir_item *btrfs_lookup_dir_index(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, u64 dir, + const char *name, int name_len, + u64 index, int mod) +{ + int ret; + struct btrfs_key key; + int ins_len = mod < 0 ? -1 : 0; + int cow = mod != 0; + + key.objectid = dir; + key.type = BTRFS_DIR_INDEX_KEY; + key.offset = index; + + ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow); + if (ret < 0) + return ERR_PTR(ret); + if (ret > 0) + return ERR_PTR(-ENOENT); + + return btrfs_match_dir_item_name(root, path, name, name_len); +} + +/* + * given a pointer into a directory item, delete it. This + * handles items that have more than one entry in them. + */ +int btrfs_delete_one_dir_name(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + struct btrfs_dir_item *di) +{ + + struct extent_buffer *leaf; + u32 sub_item_len; + u32 item_len; + int ret = 0; + + leaf = path->nodes[0]; + sub_item_len = sizeof(*di) + btrfs_dir_name_len(leaf, di) + + btrfs_dir_data_len(leaf, di); + item_len = btrfs_item_size_nr(leaf, path->slots[0]); + if (sub_item_len == item_len) { + ret = btrfs_del_item(trans, root, path); + } else { + unsigned long ptr = (unsigned long)di; + unsigned long start; + + start = btrfs_item_ptr_offset(leaf, path->slots[0]); + memmove_extent_buffer(leaf, ptr, ptr + sub_item_len, + item_len - (ptr + sub_item_len - start)); + btrfs_truncate_item(trans, root, path, item_len - sub_item_len, 1); + } + return ret; +} + +int verify_dir_item(struct btrfs_root *root, + struct extent_buffer *leaf, + struct btrfs_dir_item *dir_item) +{ + u16 namelen = BTRFS_NAME_LEN; + u8 type = btrfs_dir_type(leaf, dir_item); + + if (type >= BTRFS_FT_MAX) { + fprintf(stderr, "invalid dir item type: %d", + (int)type); + return 1; + } + + if (type == BTRFS_FT_XATTR) + namelen = XATTR_NAME_MAX; + + if (btrfs_dir_name_len(leaf, dir_item) > namelen) { + fprintf(stderr, "invalid dir item name len: %u", + (unsigned)btrfs_dir_data_len(leaf, dir_item)); + return 1; + } + + /* BTRFS_MAX_XATTR_SIZE is the same for all dir items */ + if ((btrfs_dir_data_len(leaf, dir_item) + + btrfs_dir_name_len(leaf, dir_item)) > BTRFS_MAX_XATTR_SIZE(root)) { + fprintf(stderr, "invalid dir item name + data len: %u + %u", + (unsigned)btrfs_dir_name_len(leaf, dir_item), + (unsigned)btrfs_dir_data_len(leaf, dir_item)); + return 1; + } + + return 0; +} + static struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root, struct btrfs_path *path, const char *name, int name_len) @@ -233,10 +325,18 @@ static struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root, leaf = path->nodes[0]; dir_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dir_item); total_len = btrfs_item_size_nr(leaf, path->slots[0]); + if (verify_dir_item(root, leaf, dir_item)) + return NULL; + while(cur < total_len) { this_len = sizeof(*dir_item) + btrfs_dir_name_len(leaf, dir_item) + btrfs_dir_data_len(leaf, dir_item); + if (this_len > (total_len - cur)) { + fprintf(stderr, "invalid dir item size\n"); + return NULL; + } + name_ptr = (unsigned long)(dir_item + 1); if (btrfs_dir_name_len(leaf, dir_item) == name_len && |