1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _BCACHEFS_SNAPSHOT_H
3 #define _BCACHEFS_SNAPSHOT_H
4
5 enum bch_validate_flags;
6
7 void bch2_snapshot_tree_to_text(struct printbuf *, struct bch_fs *, struct bkey_s_c);
8 int bch2_snapshot_tree_validate(struct bch_fs *, struct bkey_s_c,
9 enum bch_validate_flags);
10
11 #define bch2_bkey_ops_snapshot_tree ((struct bkey_ops) { \
12 .key_validate = bch2_snapshot_tree_validate, \
13 .val_to_text = bch2_snapshot_tree_to_text, \
14 .min_val_size = 8, \
15 })
16
17 struct bkey_i_snapshot_tree *__bch2_snapshot_tree_create(struct btree_trans *);
18
19 int bch2_snapshot_tree_lookup(struct btree_trans *, u32, struct bch_snapshot_tree *);
20
21 void bch2_snapshot_to_text(struct printbuf *, struct bch_fs *, struct bkey_s_c);
22 int bch2_snapshot_validate(struct bch_fs *, struct bkey_s_c, enum bch_validate_flags);
23 int bch2_mark_snapshot(struct btree_trans *, enum btree_id, unsigned,
24 struct bkey_s_c, struct bkey_s,
25 enum btree_iter_update_trigger_flags);
26
27 #define bch2_bkey_ops_snapshot ((struct bkey_ops) { \
28 .key_validate = bch2_snapshot_validate, \
29 .val_to_text = bch2_snapshot_to_text, \
30 .trigger = bch2_mark_snapshot, \
31 .min_val_size = 24, \
32 })
33
34 static inline struct snapshot_t *__snapshot_t(struct snapshot_table *t, u32 id)
35 {
36 u32 idx = U32_MAX - id;
37
38 return likely(t && idx < t->nr)
39 ? &t->s[idx]
40 : NULL;
41 }
42
43 static inline const struct snapshot_t *snapshot_t(struct bch_fs *c, u32 id)
44 {
45 return __snapshot_t(rcu_dereference(c->snapshots), id);
46 }
47
48 static inline u32 bch2_snapshot_tree(struct bch_fs *c, u32 id)
49 {
50 rcu_read_lock();
51 const struct snapshot_t *s = snapshot_t(c, id);
52 id = s ? s->tree : 0;
53 rcu_read_unlock();
54
55 return id;
56 }
57
58 static inline u32 __bch2_snapshot_parent_early(struct bch_fs *c, u32 id)
59 {
60 const struct snapshot_t *s = snapshot_t(c, id);
61 return s ? s->parent : 0;
62 }
63
64 static inline u32 bch2_snapshot_parent_early(struct bch_fs *c, u32 id)
65 {
66 rcu_read_lock();
67 id = __bch2_snapshot_parent_early(c, id);
68 rcu_read_unlock();
69
70 return id;
71 }
72
73 static inline u32 __bch2_snapshot_parent(struct bch_fs *c, u32 id)
74 {
75 const struct snapshot_t *s = snapshot_t(c, id);
76 if (!s)
77 return 0;
78
79 u32 parent = s->parent;
80 if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG) &&
81 parent &&
82 s->depth != snapshot_t(c, parent)->depth + 1)
83 panic("id %u depth=%u parent %u depth=%u\n",
84 id, snapshot_t(c, id)->depth,
85 parent, snapshot_t(c, parent)->depth);
86
87 return parent;
88 }
89
90 static inline u32 bch2_snapshot_parent(struct bch_fs *c, u32 id)
91 {
92 rcu_read_lock();
93 id = __bch2_snapshot_parent(c, id);
94 rcu_read_unlock();
95
96 return id;
97 }
98
99 static inline u32 bch2_snapshot_nth_parent(struct bch_fs *c, u32 id, u32 n)
100 {
101 rcu_read_lock();
102 while (n--)
103 id = __bch2_snapshot_parent(c, id);
104 rcu_read_unlock();
105
106 return id;
107 }
108
109 u32 bch2_snapshot_skiplist_get(struct bch_fs *, u32);
110
111 static inline u32 bch2_snapshot_root(struct bch_fs *c, u32 id)
112 {
113 u32 parent;
114
115 rcu_read_lock();
116 while ((parent = __bch2_snapshot_parent(c, id)))
117 id = parent;
118 rcu_read_unlock();
119
120 return id;
121 }
122
123 static inline u32 __bch2_snapshot_equiv(struct bch_fs *c, u32 id)
124 {
125 const struct snapshot_t *s = snapshot_t(c, id);
126 return s ? s->equiv : 0;
127 }
128
129 static inline u32 bch2_snapshot_equiv(struct bch_fs *c, u32 id)
130 {
131 rcu_read_lock();
132 id = __bch2_snapshot_equiv(c, id);
133 rcu_read_unlock();
134
135 return id;
136 }
137
138 static inline int bch2_snapshot_is_internal_node(struct bch_fs *c, u32 id)
139 {
140 rcu_read_lock();
141 const struct snapshot_t *s = snapshot_t(c, id);
142 int ret = s ? s->children[0] : -BCH_ERR_invalid_snapshot_node;
143 rcu_read_unlock();
144
145 return ret;
146 }
147
148 static inline int bch2_snapshot_is_leaf(struct bch_fs *c, u32 id)
149 {
150 int ret = bch2_snapshot_is_internal_node(c, id);
151 if (ret < 0)
152 return ret;
153 return !ret;
154 }
155
156 static inline u32 bch2_snapshot_depth(struct bch_fs *c, u32 parent)
157 {
158 u32 depth;
159
160 rcu_read_lock();
161 depth = parent ? snapshot_t(c, parent)->depth + 1 : 0;
162 rcu_read_unlock();
163
164 return depth;
165 }
166
167 bool __bch2_snapshot_is_ancestor(struct bch_fs *, u32, u32);
168
169 static inline bool bch2_snapshot_is_ancestor(struct bch_fs *c, u32 id, u32 ancestor)
170 {
171 return id == ancestor
172 ? true
173 : __bch2_snapshot_is_ancestor(c, id, ancestor);
174 }
175
176 static inline bool bch2_snapshot_has_children(struct bch_fs *c, u32 id)
177 {
178 rcu_read_lock();
179 const struct snapshot_t *t = snapshot_t(c, id);
180 bool ret = t && (t->children[0]|t->children[1]) != 0;
181 rcu_read_unlock();
182
183 return ret;
184 }
185
186 static inline bool snapshot_list_has_id(snapshot_id_list *s, u32 id)
187 {
188 darray_for_each(*s, i)
189 if (*i == id)
190 return true;
191 return false;
192 }
193
194 static inline bool snapshot_list_has_ancestor(struct bch_fs *c, snapshot_id_list *s, u32 id)
195 {
196 darray_for_each(*s, i)
197 if (bch2_snapshot_is_ancestor(c, id, *i))
198 return true;
199 return false;
200 }
201
202 static inline int snapshot_list_add(struct bch_fs *c, snapshot_id_list *s, u32 id)
203 {
204 BUG_ON(snapshot_list_has_id(s, id));
205 int ret = darray_push(s, id);
206 if (ret)
207 bch_err(c, "error reallocating snapshot_id_list (size %zu)", s->size);
208 return ret;
209 }
210
211 static inline int snapshot_list_add_nodup(struct bch_fs *c, snapshot_id_list *s, u32 id)
212 {
213 int ret = snapshot_list_has_id(s, id)
214 ? 0
215 : darray_push(s, id);
216 if (ret)
217 bch_err(c, "error reallocating snapshot_id_list (size %zu)", s->size);
218 return ret;
219 }
220
221 static inline int snapshot_list_merge(struct bch_fs *c, snapshot_id_list *dst, snapshot_id_list *src)
222 {
223 darray_for_each(*src, i) {
224 int ret = snapshot_list_add_nodup(c, dst, *i);
225 if (ret)
226 return ret;
227 }
228
229 return 0;
230 }
231
232 int bch2_snapshot_lookup(struct btree_trans *trans, u32 id,
233 struct bch_snapshot *s);
234 int bch2_snapshot_get_subvol(struct btree_trans *, u32,
235 struct bch_subvolume *);
236
237 /* only exported for tests: */
238 int bch2_snapshot_node_create(struct btree_trans *, u32,
239 u32 *, u32 *, unsigned);
240
241 int bch2_check_snapshot_trees(struct bch_fs *);
242 int bch2_check_snapshots(struct bch_fs *);
243 int bch2_reconstruct_snapshots(struct bch_fs *);
244 int bch2_check_key_has_snapshot(struct btree_trans *, struct btree_iter *, struct bkey_s_c);
245
246 int bch2_snapshot_node_set_deleted(struct btree_trans *, u32);
247 void bch2_delete_dead_snapshots_work(struct work_struct *);
248
249 int __bch2_key_has_snapshot_overwrites(struct btree_trans *, enum btree_id, struct bpos);
250
251 static inline int bch2_key_has_snapshot_overwrites(struct btree_trans *trans,
252 enum btree_id id,
253 struct bpos pos)
254 {
255 if (!btree_type_has_snapshots(id) ||
256 bch2_snapshot_is_leaf(trans->c, pos.snapshot) > 0)
257 return 0;
258
259 return __bch2_key_has_snapshot_overwrites(trans, id, pos);
260 }
261
262 int bch2_propagate_key_to_snapshot_leaves(struct btree_trans *, enum btree_id,
263 struct bkey_s_c, struct bpos *);
264
265 int bch2_snapshots_read(struct bch_fs *);
266 void bch2_fs_snapshots_exit(struct bch_fs *);
267
268 #endif /* _BCACHEFS_SNAPSHOT_H */
269
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