123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345 |
- // SPDX-License-Identifier: GPL-2.0+
- /*
- * BTRFS filesystem implementation for U-Boot
- *
- * 2017 Marek Behun, CZ.NIC, marek.behun@nic.cz
- */
- #include <malloc.h>
- #include "ctree.h"
- #include "btrfs.h"
- #include "disk-io.h"
- /*
- * Resolve the path of ino inside subvolume @root into @path_ret.
- *
- * @path_ret must be at least PATH_MAX size.
- */
- static int get_path_in_subvol(struct btrfs_root *root, u64 ino, char *path_ret)
- {
- struct btrfs_path path;
- struct btrfs_key key;
- char *tmp;
- u64 cur = ino;
- int ret = 0;
- tmp = malloc(PATH_MAX);
- if (!tmp)
- return -ENOMEM;
- tmp[0] = '\0';
- btrfs_init_path(&path);
- while (cur != BTRFS_FIRST_FREE_OBJECTID) {
- struct btrfs_inode_ref *iref;
- int name_len;
- btrfs_release_path(&path);
- key.objectid = cur;
- key.type = BTRFS_INODE_REF_KEY;
- key.offset = (u64)-1;
- ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
- /* Impossible */
- if (ret == 0)
- ret = -EUCLEAN;
- if (ret < 0)
- goto out;
- ret = btrfs_previous_item(root, &path, cur,
- BTRFS_INODE_REF_KEY);
- if (ret > 0)
- ret = -ENOENT;
- if (ret < 0)
- goto out;
- strncpy(tmp, path_ret, PATH_MAX);
- iref = btrfs_item_ptr(path.nodes[0], path.slots[0],
- struct btrfs_inode_ref);
- name_len = btrfs_inode_ref_name_len(path.nodes[0],
- iref);
- if (name_len > BTRFS_NAME_LEN) {
- ret = -ENAMETOOLONG;
- goto out;
- }
- read_extent_buffer(path.nodes[0], path_ret,
- (unsigned long)(iref + 1), name_len);
- path_ret[name_len] = '/';
- path_ret[name_len + 1] = '\0';
- strncat(path_ret, tmp, PATH_MAX);
- btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
- cur = key.offset;
- }
- out:
- btrfs_release_path(&path);
- free(tmp);
- return ret;
- }
- static int list_one_subvol(struct btrfs_root *root, char *path_ret)
- {
- struct btrfs_fs_info *fs_info = root->fs_info;
- struct btrfs_root *tree_root = fs_info->tree_root;
- struct btrfs_path path;
- struct btrfs_key key;
- char *tmp;
- u64 cur = root->root_key.objectid;
- int ret = 0;
- tmp = malloc(PATH_MAX);
- if (!tmp)
- return -ENOMEM;
- tmp[0] = '\0';
- path_ret[0] = '\0';
- btrfs_init_path(&path);
- while (cur != BTRFS_FS_TREE_OBJECTID) {
- struct btrfs_root_ref *rr;
- struct btrfs_key location;
- int name_len;
- u64 ino;
- key.objectid = cur;
- key.type = BTRFS_ROOT_BACKREF_KEY;
- key.offset = (u64)-1;
- btrfs_release_path(&path);
- ret = btrfs_search_slot(NULL, tree_root, &key, &path, 0, 0);
- if (ret == 0)
- ret = -EUCLEAN;
- if (ret < 0)
- goto out;
- ret = btrfs_previous_item(tree_root, &path, cur,
- BTRFS_ROOT_BACKREF_KEY);
- if (ret > 0)
- ret = -ENOENT;
- if (ret < 0)
- goto out;
- /* Get the subvolume name */
- rr = btrfs_item_ptr(path.nodes[0], path.slots[0],
- struct btrfs_root_ref);
- strncpy(tmp, path_ret, PATH_MAX);
- name_len = btrfs_root_ref_name_len(path.nodes[0], rr);
- if (name_len > BTRFS_NAME_LEN) {
- ret = -ENAMETOOLONG;
- goto out;
- }
- ino = btrfs_root_ref_dirid(path.nodes[0], rr);
- read_extent_buffer(path.nodes[0], path_ret,
- (unsigned long)(rr + 1), name_len);
- path_ret[name_len] = '/';
- path_ret[name_len + 1] = '\0';
- strncat(path_ret, tmp, PATH_MAX);
- /* Get the path inside the parent subvolume */
- btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
- location.objectid = key.offset;
- location.type = BTRFS_ROOT_ITEM_KEY;
- location.offset = (u64)-1;
- root = btrfs_read_fs_root(fs_info, &location);
- if (IS_ERR(root)) {
- ret = PTR_ERR(root);
- goto out;
- }
- ret = get_path_in_subvol(root, ino, path_ret);
- if (ret < 0)
- goto out;
- cur = key.offset;
- }
- /* Add the leading '/' */
- strncpy(tmp, path_ret, PATH_MAX);
- strncpy(path_ret, "/", PATH_MAX);
- strncat(path_ret, tmp, PATH_MAX);
- out:
- btrfs_release_path(&path);
- free(tmp);
- return ret;
- }
- static int list_subvolums(struct btrfs_fs_info *fs_info)
- {
- struct btrfs_root *tree_root = fs_info->tree_root;
- struct btrfs_root *root;
- struct btrfs_path path;
- struct btrfs_key key;
- char *result;
- int ret = 0;
- result = malloc(PATH_MAX);
- if (!result)
- return -ENOMEM;
- ret = list_one_subvol(fs_info->fs_root, result);
- if (ret < 0)
- goto out;
- root = fs_info->fs_root;
- printf("ID %llu gen %llu path %.*s\n",
- root->root_key.objectid, btrfs_root_generation(&root->root_item),
- PATH_MAX, result);
- key.objectid = BTRFS_FIRST_FREE_OBJECTID;
- key.type = BTRFS_ROOT_ITEM_KEY;
- key.offset = 0;
- btrfs_init_path(&path);
- ret = btrfs_search_slot(NULL, tree_root, &key, &path, 0, 0);
- if (ret < 0)
- goto out;
- while (1) {
- if (path.slots[0] >= btrfs_header_nritems(path.nodes[0]))
- goto next;
- btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
- if (key.objectid > BTRFS_LAST_FREE_OBJECTID)
- break;
- if (key.objectid < BTRFS_FIRST_FREE_OBJECTID ||
- key.type != BTRFS_ROOT_ITEM_KEY)
- goto next;
- key.offset = (u64)-1;
- root = btrfs_read_fs_root(fs_info, &key);
- if (IS_ERR(root)) {
- ret = PTR_ERR(root);
- if (ret == -ENOENT)
- goto next;
- }
- ret = list_one_subvol(root, result);
- if (ret < 0)
- goto out;
- printf("ID %llu gen %llu path %.*s\n",
- root->root_key.objectid,
- btrfs_root_generation(&root->root_item),
- PATH_MAX, result);
- next:
- ret = btrfs_next_item(tree_root, &path);
- if (ret < 0)
- goto out;
- if (ret > 0) {
- ret = 0;
- break;
- }
- }
- out:
- free(result);
- return ret;
- }
- static int get_subvol_name(u64 subvolid, char *name, int max_len)
- {
- struct btrfs_root_ref rref;
- struct btrfs_inode_ref iref;
- struct __btrfs_root root;
- u64 dir;
- char tmp[BTRFS_NAME_LEN];
- char *ptr;
- ptr = name + max_len - 1;
- *ptr = '\0';
- while (subvolid != BTRFS_FS_TREE_OBJECTID) {
- subvolid = btrfs_lookup_root_ref(subvolid, &rref, tmp);
- if (subvolid == -1ULL)
- return -1;
- ptr -= rref.name_len + 1;
- if (ptr < name)
- goto too_long;
- memcpy(ptr + 1, tmp, rref.name_len);
- *ptr = '/';
- if (btrfs_find_root(subvolid, &root, NULL))
- return -1;
- dir = rref.dirid;
- while (dir != BTRFS_FIRST_FREE_OBJECTID) {
- dir = __btrfs_lookup_inode_ref(&root, dir, &iref, tmp);
- if (dir == -1ULL)
- return -1;
- ptr -= iref.name_len + 1;
- if (ptr < name)
- goto too_long;
- memcpy(ptr + 1, tmp, iref.name_len);
- *ptr = '/';
- }
- }
- if (ptr == name + max_len - 1) {
- name[0] = '/';
- name[1] = '\0';
- } else {
- memmove(name, ptr, name + max_len - ptr);
- }
- return 0;
- too_long:
- printf("%s: subvolume name too long\n", __func__);
- return -1;
- }
- u64 btrfs_get_default_subvol_objectid(void)
- {
- struct btrfs_dir_item item;
- if (__btrfs_lookup_dir_item(&btrfs_info.tree_root,
- btrfs_info.sb.root_dir_objectid, "default", 7,
- &item))
- return BTRFS_FS_TREE_OBJECTID;
- return item.location.objectid;
- }
- static void list_subvols(u64 tree, char *nameptr, int max_name_len, int level)
- {
- struct btrfs_key key, *found_key;
- struct __btrfs_path path;
- struct btrfs_root_ref *ref;
- int res;
- key.objectid = tree;
- key.type = BTRFS_ROOT_REF_KEY;
- key.offset = 0;
- if (btrfs_search_tree(&btrfs_info.tree_root, &key, &path))
- return;
- do {
- found_key = btrfs_path_leaf_key(&path);
- if (btrfs_comp_keys_type(&key, found_key))
- break;
- ref = btrfs_path_item_ptr(&path, struct btrfs_root_ref);
- btrfs_root_ref_to_cpu(ref);
- printf("ID %llu parent %llu name ", found_key->offset, tree);
- if (nameptr && !get_subvol_name(found_key->offset, nameptr,
- max_name_len))
- printf("%s\n", nameptr);
- else
- printf("%.*s\n", (int) ref->name_len,
- (const char *) (ref + 1));
- if (level > 0)
- list_subvols(found_key->offset, nameptr, max_name_len,
- level - 1);
- else
- printf("%s: Too much recursion, maybe skipping some "
- "subvolumes\n", __func__);
- } while (!(res = btrfs_next_slot(&path)));
- __btrfs_free_path(&path);
- }
- void btrfs_list_subvols(void)
- {
- struct btrfs_fs_info *fs_info = current_fs_info;
- int ret;
- if (!fs_info)
- return;
- ret = list_subvolums(fs_info);
- if (ret < 0)
- error("failed to list subvolume: %d", ret);
- }
|