blob: 54e0ab454633e9a5fb6a89353c85b6e5c658e49b [file] [log] [blame]
Marek BehĂșn21a14fa2017-09-03 17:00:28 +02001/*
2 * BTRFS filesystem implementation for U-Boot
3 *
4 * 2017 Marek Behun, CZ.NIC, marek.behun@nic.cz
5 *
6 * SPDX-License-Identifier: GPL-2.0+
7 */
8
9#include "btrfs.h"
10#include <malloc.h>
11
12static int get_subvol_name(u64 subvolid, char *name, int max_len)
13{
14 struct btrfs_root_ref rref;
15 struct btrfs_inode_ref iref;
16 struct btrfs_root root;
17 u64 dir;
18 char tmp[max(BTRFS_VOL_NAME_MAX, BTRFS_NAME_MAX)];
19 char *ptr;
20
21 ptr = name + max_len - 1;
22 *ptr = '\0';
23
24 while (subvolid != BTRFS_FS_TREE_OBJECTID) {
25 subvolid = btrfs_lookup_root_ref(subvolid, &rref, tmp);
26
27 if (subvolid == -1ULL)
28 return -1;
29
30 ptr -= rref.name_len + 1;
31 if (ptr < name)
32 goto too_long;
33
34 memcpy(ptr + 1, tmp, rref.name_len);
35 *ptr = '/';
36
37 if (btrfs_find_root(subvolid, &root, NULL))
38 return -1;
39
40 dir = rref.dirid;
41
42 while (dir != BTRFS_FIRST_FREE_OBJECTID) {
43 dir = btrfs_lookup_inode_ref(&root, dir, &iref, tmp);
44
45 if (dir == -1ULL)
46 return -1;
47
48 ptr -= iref.name_len + 1;
49 if (ptr < name)
50 goto too_long;
51
52 memcpy(ptr + 1, tmp, iref.name_len);
53 *ptr = '/';
54 }
55 }
56
57 if (ptr == name + max_len - 1) {
58 name[0] = '/';
59 name[1] = '\0';
60 } else {
61 memmove(name, ptr, name + max_len - ptr);
62 }
63
64 return 0;
65
66too_long:
67 printf("%s: subvolume name too long\n", __func__);
68 return -1;
69}
70
71u64 btrfs_get_default_subvol_objectid(void)
72{
73 struct btrfs_dir_item item;
74
75 if (btrfs_lookup_dir_item(&btrfs_info.tree_root,
76 btrfs_info.sb.root_dir_objectid, "default", 7,
77 &item))
78 return BTRFS_FS_TREE_OBJECTID;
79 return item.location.objectid;
80}
81
82static void list_subvols(u64 tree, char *nameptr, int max_name_len, int level)
83{
84 struct btrfs_key key, *found_key;
85 struct btrfs_path path;
86 struct btrfs_root_ref *ref;
87 int res;
88
89 key.objectid = tree;
90 key.type = BTRFS_ROOT_REF_KEY;
91 key.offset = 0;
92
93 if (btrfs_search_tree(&btrfs_info.tree_root, &key, &path))
94 return;
95
96 do {
97 found_key = btrfs_path_leaf_key(&path);
98 if (btrfs_comp_keys_type(&key, found_key))
99 break;
100
101 ref = btrfs_path_item_ptr(&path, struct btrfs_root_ref);
102 btrfs_root_ref_to_cpu(ref);
103
104 printf("ID %llu parent %llu name ", found_key->offset, tree);
105 if (nameptr && !get_subvol_name(found_key->offset, nameptr,
106 max_name_len))
107 printf("%s\n", nameptr);
108 else
109 printf("%.*s\n", (int) ref->name_len,
110 (const char *) (ref + 1));
111
112 if (level > 0)
113 list_subvols(found_key->offset, nameptr, max_name_len,
114 level - 1);
115 else
116 printf("%s: Too much recursion, maybe skipping some "
117 "subvolumes\n", __func__);
118 } while (!(res = btrfs_next_slot(&path)));
119
120 btrfs_free_path(&path);
121}
122
123void btrfs_list_subvols(void)
124{
125 char *nameptr = malloc(4096);
126
127 list_subvols(BTRFS_FS_TREE_OBJECTID, nameptr, nameptr ? 4096 : 0, 40);
128
129 if (nameptr)
130 free(nameptr);
131}