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_invalid(struct bch_fs *, struct bkey_s_c,
9 enum bch_validate_flags, struct printbuf *);
10
11 #define bch2_bkey_ops_snapshot_tree ((struct bkey_ops) { \
12 .key_invalid = bch2_snapshot_tree_invalid, \
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_invalid(struct bch_fs *, struct bkey_s_c,
23 enum bch_validate_flags, struct printbuf *);
24 int bch2_mark_snapshot(struct btree_trans *, enum btree_id, unsigned,
25 struct bkey_s_c, struct bkey_s,
26 enum btree_iter_update_trigger_flags);
27
28 #define bch2_bkey_ops_snapshot ((struct bkey_ops) { \
29 .key_invalid = bch2_snapshot_invalid, \
30 .val_to_text = bch2_snapshot_to_text, \
31 .trigger = bch2_mark_snapshot, \
32 .min_val_size = 24, \
33 })
34
35 static inline struct snapshot_t *__snapshot_t(struct snapshot_table *t, u32 id)
36 {
37 u32 idx = U32_MAX - id;
38
39 return likely(t && idx < t->nr)
40 ? &t->s[idx]
41 : NULL;
42 }
43
44 static inline const struct snapshot_t *snapshot_t(struct bch_fs *c, u32 id)
45 {
46 return __snapshot_t(rcu_dereference(c->snapshots), id);
47 }
48
49 static inline u32 bch2_snapshot_tree(struct bch_fs *c, u32 id)
50 {
51 rcu_read_lock();
52 const struct snapshot_t *s = snapshot_t(c, id);
53 id = s ? s->tree : 0;
54 rcu_read_unlock();
55
56 return id;
57 }
58
59 static inline u32 __bch2_snapshot_parent_early(struct bch_fs *c, u32 id)
60 {
61 const struct snapshot_t *s = snapshot_t(c, id);
62 return s ? s->parent : 0;
63 }
64
65 static inline u32 bch2_snapshot_parent_early(struct bch_fs *c, u32 id)
66 {
67 rcu_read_lock();
68 id = __bch2_snapshot_parent_early(c, id);
69 rcu_read_unlock();
70
71 return id;
72 }
73
74 static inline u32 __bch2_snapshot_parent(struct bch_fs *c, u32 id)
75 {
76 const struct snapshot_t *s = snapshot_t(c, id);
77 if (!s)
78 return 0;
79
80 u32 parent = s->parent;
81 if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG) &&
82 parent &&
83 s->depth != snapshot_t(c, parent)->depth + 1)
84 panic("id %u depth=%u parent %u depth=%u\n",
85 id, snapshot_t(c, id)->depth,
86 parent, snapshot_t(c, parent)->depth);
87
88 return parent;
89 }
90
91 static inline u32 bch2_snapshot_parent(struct bch_fs *c, u32 id)
92 {
93 rcu_read_lock();
94 id = __bch2_snapshot_parent(c, id);
95 rcu_read_unlock();
96
97 return id;
98 }
99
100 static inline u32 bch2_snapshot_nth_parent(struct bch_fs *c, u32 id, u32 n)
101 {
102 rcu_read_lock();
103 while (n--)
104 id = __bch2_snapshot_parent(c, id);
105 rcu_read_unlock();
106
107 return id;
108 }
109
110 u32 bch2_snapshot_skiplist_get(struct bch_fs *, u32);
111
112 static inline u32 bch2_snapshot_root(struct bch_fs *c, u32 id)
113 {
114 u32 parent;
115
116 rcu_read_lock();
117 while ((parent = __bch2_snapshot_parent(c, id)))
118 id = parent;
119 rcu_read_unlock();
120
121 return id;
122 }
123
124 static inline u32 __bch2_snapshot_equiv(struct bch_fs *c, u32 id)
125 {
126 const struct snapshot_t *s = snapshot_t(c, id);
127 return s ? s->equiv : 0;
128 }
129
130 static inline u32 bch2_snapshot_equiv(struct bch_fs *c, u32 id)
131 {
132 rcu_read_lock();
133 id = __bch2_snapshot_equiv(c, id);
134 rcu_read_unlock();
135
136 return id;
137 }
138
139 static inline int bch2_snapshot_is_internal_node(struct bch_fs *c, u32 id)
140 {
141 rcu_read_lock();
142 const struct snapshot_t *s = snapshot_t(c, id);
143 int ret = s ? s->children[0] : -BCH_ERR_invalid_snapshot_node;
144 rcu_read_unlock();
145
146 return ret;
147 }
148
149 static inline int bch2_snapshot_is_leaf(struct bch_fs *c, u32 id)
150 {
151 int ret = bch2_snapshot_is_internal_node(c, id);
152 if (ret < 0)
153 return ret;
154 return !ret;
155 }
156
157 static inline u32 bch2_snapshot_depth(struct bch_fs *c, u32 parent)
158 {
159 u32 depth;
160
161 rcu_read_lock();
162 depth = parent ? snapshot_t(c, parent)->depth + 1 : 0;
163 rcu_read_unlock();
164
165 return depth;
166 }
167
168 bool __bch2_snapshot_is_ancestor(struct bch_fs *, u32, u32);
169
170 static inline bool bch2_snapshot_is_ancestor(struct bch_fs *c, u32 id, u32 ancestor)
171 {
172 return id == ancestor
173 ? true
174 : __bch2_snapshot_is_ancestor(c, id, ancestor);
175 }
176
177 static inline bool bch2_snapshot_has_children(struct bch_fs *c, u32 id)
178 {
179 rcu_read_lock();
180 const struct snapshot_t *t = snapshot_t(c, id);
181 bool ret = t && (t->children[0]|t->children[1]) != 0;
182 rcu_read_unlock();
183
184 return ret;
185 }
186
187 static inline bool snapshot_list_has_id(snapshot_id_list *s, u32 id)
188 {
189 darray_for_each(*s, i)
190 if (*i == id)
191 return true;
192 return false;
193 }
194
195 static inline bool snapshot_list_has_ancestor(struct bch_fs *c, snapshot_id_list *s, u32 id)
196 {
197 darray_for_each(*s, i)
198 if (bch2_snapshot_is_ancestor(c, id, *i))
199 return true;
200 return false;
201 }
202
203 static inline int snapshot_list_add(struct bch_fs *c, snapshot_id_list *s, u32 id)
204 {
205 BUG_ON(snapshot_list_has_id(s, id));
206 int ret = darray_push(s, id);
207 if (ret)
208 bch_err(c, "error reallocating snapshot_id_list (size %zu)", s->size);
209 return ret;
210 }
211
212 static inline int snapshot_list_add_nodup(struct bch_fs *c, snapshot_id_list *s, u32 id)
213 {
214 int ret = snapshot_list_has_id(s, id)
215 ? 0
216 : darray_push(s, id);
217 if (ret)
218 bch_err(c, "error reallocating snapshot_id_list (size %zu)", s->size);
219 return ret;
220 }
221
222 static inline int snapshot_list_merge(struct bch_fs *c, snapshot_id_list *dst, snapshot_id_list *src)
223 {
224 darray_for_each(*src, i) {
225 int ret = snapshot_list_add_nodup(c, dst, *i);
226 if (ret)
227 return ret;
228 }
229
230 return 0;
231 }
232
233 int bch2_snapshot_lookup(struct btree_trans *trans, u32 id,
234 struct bch_snapshot *s);
235 int bch2_snapshot_get_subvol(struct btree_trans *, u32,
236 struct bch_subvolume *);
237
238 /* only exported for tests: */
239 int bch2_snapshot_node_create(struct btree_trans *, u32,
240 u32 *, u32 *, unsigned);
241
242 int bch2_check_snapshot_trees(struct bch_fs *);
243 int bch2_check_snapshots(struct bch_fs *);
244 int bch2_reconstruct_snapshots(struct bch_fs *);
245 int bch2_check_key_has_snapshot(struct btree_trans *, struct btree_iter *, struct bkey_s_c);
246
247 int bch2_snapshot_node_set_deleted(struct btree_trans *, u32);
248 void bch2_delete_dead_snapshots_work(struct work_struct *);
249
250 int __bch2_key_has_snapshot_overwrites(struct btree_trans *, enum btree_id, struct bpos);
251
252 static inline int bch2_key_has_snapshot_overwrites(struct btree_trans *trans,
253 enum btree_id id,
254 struct bpos pos)
255 {
256 if (!btree_type_has_snapshots(id) ||
257 bch2_snapshot_is_leaf(trans->c, pos.snapshot) > 0)
258 return 0;
259
260 return __bch2_key_has_snapshot_overwrites(trans, id, pos);
261 }
262
263 int bch2_propagate_key_to_snapshot_leaves(struct btree_trans *, enum btree_id,
264 struct bkey_s_c, struct bpos *);
265
266 int bch2_snapshots_read(struct bch_fs *);
267 void bch2_fs_snapshots_exit(struct bch_fs *);
268
269 #endif /* _BCACHEFS_SNAPSHOT_H */
270
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