diff options
Diffstat (limited to 'roms/u-boot/fs/btrfs/dir-item.c')
| -rw-r--r-- | roms/u-boot/fs/btrfs/dir-item.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/roms/u-boot/fs/btrfs/dir-item.c b/roms/u-boot/fs/btrfs/dir-item.c new file mode 100644 index 000000000..aab197a6d --- /dev/null +++ b/roms/u-boot/fs/btrfs/dir-item.c @@ -0,0 +1,168 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * BTRFS filesystem implementation for U-Boot + * + * 2017 Marek Behun, CZ.NIC, marek.behun@nic.cz + */ + +#include "btrfs.h" +#include "disk-io.h" + +static 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_XATTR) + namelen = XATTR_NAME_MAX; + + if (btrfs_dir_name_len(leaf, dir_item) > namelen) { + fprintf(stderr, "invalid dir item name len: %u\n", + (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->fs_info)) { + fprintf(stderr, "invalid dir item name + data len: %u + %u\n", + (unsigned)btrfs_dir_name_len(leaf, dir_item), + (unsigned)btrfs_dir_data_len(leaf, dir_item)); + return 1; + } + + return 0; +} + +struct btrfs_dir_item *btrfs_match_dir_item_name(struct btrfs_root *root, + struct btrfs_path *path, + const char *name, int name_len) +{ + struct btrfs_dir_item *dir_item; + unsigned long name_ptr; + u32 total_len; + u32 cur = 0; + u32 this_len; + struct extent_buffer *leaf; + + 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 && + memcmp_extent_buffer(leaf, name, name_ptr, name_len) == 0) + return dir_item; + + cur += this_len; + dir_item = (struct btrfs_dir_item *)((char *)dir_item + + this_len); + } + return NULL; +} + +struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, u64 dir, + const char *name, int name_len, + int mod) +{ + int ret; + struct btrfs_key key; + int ins_len = mod < 0 ? -1 : 0; + int cow = mod != 0; + struct btrfs_key found_key; + struct extent_buffer *leaf; + + key.objectid = dir; + key.type = BTRFS_DIR_ITEM_KEY; + + key.offset = btrfs_name_hash(name, name_len); + + ret = btrfs_search_slot(trans, root, &key, path, ins_len, cow); + if (ret < 0) + return ERR_PTR(ret); + if (ret > 0) { + if (path->slots[0] == 0) + return NULL; + path->slots[0]--; + } + + leaf = path->nodes[0]; + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); + + if (found_key.objectid != dir || + found_key.type != BTRFS_DIR_ITEM_KEY || + found_key.offset != key.offset) + return NULL; + + return btrfs_match_dir_item_name(root, path, name, name_len); +} + +int btrfs_iter_dir(struct btrfs_root *root, u64 ino, + btrfs_iter_dir_callback_t callback) +{ + struct btrfs_path path; + struct btrfs_key key; + int ret; + + btrfs_init_path(&path); + key.objectid = ino; + key.type = BTRFS_DIR_INDEX_KEY; + key.offset = 0; + + ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0); + if (ret < 0) + return ret; + /* Should not happen */ + if (ret == 0) { + ret = -EUCLEAN; + goto out; + } + if (path.slots[0] >= btrfs_header_nritems(path.nodes[0])) { + ret = btrfs_next_leaf(root, &path); + if (ret < 0) + goto out; + if (ret > 0) { + ret = 0; + goto out; + } + } + do { + struct btrfs_dir_item *di; + + btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]); + if (key.objectid != ino || key.type != BTRFS_DIR_INDEX_KEY) + break; + di = btrfs_item_ptr(path.nodes[0], path.slots[0], + struct btrfs_dir_item); + if (verify_dir_item(root, path.nodes[0], di)) { + ret = -EUCLEAN; + goto out; + } + ret = callback(root, path.nodes[0], di); + if (ret < 0) + goto out; + } while (!(ret = btrfs_next_item(root, &path))); + + if (ret > 0) + ret = 0; +out: + btrfs_release_path(&path); + return ret; +} |