1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _BCACHEFS_SNAPSHOT_H 3 #define _BCACHEFS_SNAPSHOT_H 4 5 void bch2_snapshot_tree_to_text(struct printbuf *, struct bch_fs *, struct bkey_s_c); 6 int bch2_snapshot_tree_validate(struct bch_fs *, struct bkey_s_c, 7 struct bkey_validate_context); 8 9 #define bch2_bkey_ops_snapshot_tree ((struct bkey_ops) { \ 10 .key_validate = bch2_snapshot_tree_validate, \ 11 .val_to_text = bch2_snapshot_tree_to_text, \ 12 .min_val_size = 8, \ 13 }) 14 15 struct bkey_i_snapshot_tree *__bch2_snapshot_tree_create(struct btree_trans *); 16 17 int bch2_snapshot_tree_lookup(struct btree_trans *, u32, struct bch_snapshot_tree *); 18 19 void bch2_snapshot_to_text(struct printbuf *, struct bch_fs *, struct bkey_s_c); 20 int bch2_snapshot_validate(struct bch_fs *, struct bkey_s_c, 21 struct bkey_validate_context); 22 int bch2_mark_snapshot(struct btree_trans *, enum btree_id, unsigned, 23 struct bkey_s_c, struct bkey_s, 24 enum btree_iter_update_trigger_flags); 25 26 #define bch2_bkey_ops_snapshot ((struct bkey_ops) { \ 27 .key_validate = bch2_snapshot_validate, \ 28 .val_to_text = bch2_snapshot_to_text, \ 29 .trigger = bch2_mark_snapshot, \ 30 .min_val_size = 24, \ 31 }) 32 33 static inline struct snapshot_t *__snapshot_t(struct snapshot_table *t, u32 id) 34 { 35 u32 idx = U32_MAX - id; 36 37 return likely(t && idx < t->nr) 38 ? &t->s[idx] 39 : NULL; 40 } 41 42 static inline const struct snapshot_t *snapshot_t(struct bch_fs *c, u32 id) 43 { 44 return __snapshot_t(rcu_dereference(c->snapshots), id); 45 } 46 47 static inline u32 bch2_snapshot_tree(struct bch_fs *c, u32 id) 48 { 49 rcu_read_lock(); 50 const struct snapshot_t *s = snapshot_t(c, id); 51 id = s ? s->tree : 0; 52 rcu_read_unlock(); 53 54 return id; 55 } 56 57 static inline u32 __bch2_snapshot_parent_early(struct bch_fs *c, u32 id) 58 { 59 const struct snapshot_t *s = snapshot_t(c, id); 60 return s ? s->parent : 0; 61 } 62 63 static inline u32 bch2_snapshot_parent_early(struct bch_fs *c, u32 id) 64 { 65 rcu_read_lock(); 66 id = __bch2_snapshot_parent_early(c, id); 67 rcu_read_unlock(); 68 69 return id; 70 } 71 72 static inline u32 __bch2_snapshot_parent(struct bch_fs *c, u32 id) 73 { 74 const struct snapshot_t *s = snapshot_t(c, id); 75 if (!s) 76 return 0; 77 78 u32 parent = s->parent; 79 if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG) && 80 parent && 81 s->depth != snapshot_t(c, parent)->depth + 1) 82 panic("id %u depth=%u parent %u depth=%u\n", 83 id, snapshot_t(c, id)->depth, 84 parent, snapshot_t(c, parent)->depth); 85 86 return parent; 87 } 88 89 static inline u32 bch2_snapshot_parent(struct bch_fs *c, u32 id) 90 { 91 rcu_read_lock(); 92 id = __bch2_snapshot_parent(c, id); 93 rcu_read_unlock(); 94 95 return id; 96 } 97 98 static inline u32 bch2_snapshot_nth_parent(struct bch_fs *c, u32 id, u32 n) 99 { 100 rcu_read_lock(); 101 while (n--) 102 id = __bch2_snapshot_parent(c, id); 103 rcu_read_unlock(); 104 105 return id; 106 } 107 108 u32 bch2_snapshot_skiplist_get(struct bch_fs *, u32); 109 110 static inline u32 bch2_snapshot_root(struct bch_fs *c, u32 id) 111 { 112 u32 parent; 113 114 rcu_read_lock(); 115 while ((parent = __bch2_snapshot_parent(c, id))) 116 id = parent; 117 rcu_read_unlock(); 118 119 return id; 120 } 121 122 static inline bool __bch2_snapshot_exists(struct bch_fs *c, u32 id) 123 { 124 const struct snapshot_t *s = snapshot_t(c, id); 125 return s ? s->live : 0; 126 } 127 128 static inline bool bch2_snapshot_exists(struct bch_fs *c, u32 id) 129 { 130 rcu_read_lock(); 131 bool ret = __bch2_snapshot_exists(c, id); 132 rcu_read_unlock(); 133 134 return ret; 135 } 136 137 static inline int bch2_snapshot_is_internal_node(struct bch_fs *c, u32 id) 138 { 139 rcu_read_lock(); 140 const struct snapshot_t *s = snapshot_t(c, id); 141 int ret = s ? s->children[0] : -BCH_ERR_invalid_snapshot_node; 142 rcu_read_unlock(); 143 144 return ret; 145 } 146 147 static inline int bch2_snapshot_is_leaf(struct bch_fs *c, u32 id) 148 { 149 int ret = bch2_snapshot_is_internal_node(c, id); 150 if (ret < 0) 151 return ret; 152 return !ret; 153 } 154 155 static inline u32 bch2_snapshot_depth(struct bch_fs *c, u32 parent) 156 { 157 u32 depth; 158 159 rcu_read_lock(); 160 depth = parent ? snapshot_t(c, parent)->depth + 1 : 0; 161 rcu_read_unlock(); 162 163 return depth; 164 } 165 166 bool __bch2_snapshot_is_ancestor(struct bch_fs *, u32, u32); 167 168 static inline bool bch2_snapshot_is_ancestor(struct bch_fs *c, u32 id, u32 ancestor) 169 { 170 return id == ancestor 171 ? true 172 : __bch2_snapshot_is_ancestor(c, id, ancestor); 173 } 174 175 static inline bool bch2_snapshot_has_children(struct bch_fs *c, u32 id) 176 { 177 rcu_read_lock(); 178 const struct snapshot_t *t = snapshot_t(c, id); 179 bool ret = t && (t->children[0]|t->children[1]) != 0; 180 rcu_read_unlock(); 181 182 return ret; 183 } 184 185 static inline bool snapshot_list_has_id(snapshot_id_list *s, u32 id) 186 { 187 darray_for_each(*s, i) 188 if (*i == id) 189 return true; 190 return false; 191 } 192 193 static inline bool snapshot_list_has_ancestor(struct bch_fs *c, snapshot_id_list *s, u32 id) 194 { 195 darray_for_each(*s, i) 196 if (bch2_snapshot_is_ancestor(c, id, *i)) 197 return true; 198 return false; 199 } 200 201 static inline int snapshot_list_add(struct bch_fs *c, snapshot_id_list *s, u32 id) 202 { 203 BUG_ON(snapshot_list_has_id(s, id)); 204 int ret = darray_push(s, id); 205 if (ret) 206 bch_err(c, "error reallocating snapshot_id_list (size %zu)", s->size); 207 return ret; 208 } 209 210 static inline int snapshot_list_add_nodup(struct bch_fs *c, snapshot_id_list *s, u32 id) 211 { 212 int ret = snapshot_list_has_id(s, id) 213 ? 0 214 : darray_push(s, id); 215 if (ret) 216 bch_err(c, "error reallocating snapshot_id_list (size %zu)", s->size); 217 return ret; 218 } 219 220 static inline int snapshot_list_merge(struct bch_fs *c, snapshot_id_list *dst, snapshot_id_list *src) 221 { 222 darray_for_each(*src, i) { 223 int ret = snapshot_list_add_nodup(c, dst, *i); 224 if (ret) 225 return ret; 226 } 227 228 return 0; 229 } 230 231 int bch2_snapshot_lookup(struct btree_trans *trans, u32 id, 232 struct bch_snapshot *s); 233 int bch2_snapshot_get_subvol(struct btree_trans *, u32, 234 struct bch_subvolume *); 235 236 /* only exported for tests: */ 237 int bch2_snapshot_node_create(struct btree_trans *, u32, 238 u32 *, u32 *, unsigned); 239 240 int bch2_check_snapshot_trees(struct bch_fs *); 241 int bch2_check_snapshots(struct bch_fs *); 242 int bch2_reconstruct_snapshots(struct bch_fs *); 243 int bch2_check_key_has_snapshot(struct btree_trans *, struct btree_iter *, struct bkey_s_c); 244 245 int bch2_snapshot_node_set_deleted(struct btree_trans *, u32); 246 void bch2_delete_dead_snapshots_work(struct work_struct *); 247 248 int __bch2_key_has_snapshot_overwrites(struct btree_trans *, enum btree_id, struct bpos); 249 250 static inline int bch2_key_has_snapshot_overwrites(struct btree_trans *trans, 251 enum btree_id id, 252 struct bpos pos) 253 { 254 if (!btree_type_has_snapshots(id) || 255 bch2_snapshot_is_leaf(trans->c, pos.snapshot) > 0) 256 return 0; 257 258 return __bch2_key_has_snapshot_overwrites(trans, id, pos); 259 } 260 261 int bch2_snapshots_read(struct bch_fs *); 262 void bch2_fs_snapshots_exit(struct bch_fs *); 263 264 #endif /* _BCACHEFS_SNAPSHOT_H */ 265