1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _BCACHEFS_BTREE_UPDATE_INTERIOR_H 3 #define _BCACHEFS_BTREE_UPDATE_INTERIOR_H 4 5 #include "btree_cache.h" 6 #include "btree_locking.h" 7 #include "btree_update.h" 8 9 #define BTREE_UPDATE_NODES_MAX ((BTREE_MAX_DEPTH - 2) * 2 + GC_MERGE_NODES) 10 11 #define BTREE_UPDATE_JOURNAL_RES (BTREE_UPDATE_NODES_MAX * (BKEY_BTREE_PTR_U64s_MAX + 1)) 12 13 int bch2_btree_node_check_topology(struct btree_trans *, struct btree *); 14 15 #define BTREE_UPDATE_MODES() \ 16 x(none) \ 17 x(node) \ 18 x(root) \ 19 x(update) 20 21 enum btree_update_mode { 22 #define x(n) BTREE_UPDATE_##n, 23 BTREE_UPDATE_MODES() 24 #undef x 25 }; 26 27 /* 28 * Tracks an in progress split/rewrite of a btree node and the update to the 29 * parent node: 30 * 31 * When we split/rewrite a node, we do all the updates in memory without 32 * waiting for any writes to complete - we allocate the new node(s) and update 33 * the parent node, possibly recursively up to the root. 34 * 35 * The end result is that we have one or more new nodes being written - 36 * possibly several, if there were multiple splits - and then a write (updating 37 * an interior node) which will make all these new nodes visible. 38 * 39 * Additionally, as we split/rewrite nodes we free the old nodes - but the old 40 * nodes can't be freed (their space on disk can't be reclaimed) until the 41 * update to the interior node that makes the new node visible completes - 42 * until then, the old nodes are still reachable on disk. 43 * 44 */ 45 struct btree_update { 46 struct closure cl; 47 struct bch_fs *c; 48 u64 start_time; 49 unsigned long ip_started; 50 51 struct list_head list; 52 struct list_head unwritten_list; 53 54 enum btree_update_mode mode; 55 enum bch_trans_commit_flags flags; 56 unsigned nodes_written:1; 57 unsigned took_gc_lock:1; 58 59 enum btree_id btree_id; 60 unsigned update_level_start; 61 unsigned update_level_end; 62 63 struct disk_reservation disk_res; 64 65 /* 66 * BTREE_UPDATE_node: 67 * The update that made the new nodes visible was a regular update to an 68 * existing interior node - @b. We can't write out the update to @b 69 * until the new nodes we created are finished writing, so we block @b 70 * from writing by putting this btree_interior update on the 71 * @b->write_blocked list with @write_blocked_list: 72 */ 73 struct btree *b; 74 struct list_head write_blocked_list; 75 76 /* 77 * We may be freeing nodes that were dirty, and thus had journal entries 78 * pinned: we need to transfer the oldest of those pins to the 79 * btree_update operation, and release it when the new node(s) 80 * are all persistent and reachable: 81 */ 82 struct journal_entry_pin journal; 83 84 /* Preallocated nodes we reserve when we start the update: */ 85 struct prealloc_nodes { 86 struct btree *b[BTREE_UPDATE_NODES_MAX]; 87 unsigned nr; 88 } prealloc_nodes[2]; 89 90 /* Nodes being freed: */ 91 struct keylist old_keys; 92 u64 _old_keys[BTREE_UPDATE_NODES_MAX * 93 BKEY_BTREE_PTR_U64s_MAX]; 94 95 /* Nodes being added: */ 96 struct keylist new_keys; 97 u64 _new_keys[BTREE_UPDATE_NODES_MAX * 98 BKEY_BTREE_PTR_U64s_MAX]; 99 100 /* New nodes, that will be made reachable by this update: */ 101 struct btree *new_nodes[BTREE_UPDATE_NODES_MAX]; 102 unsigned nr_new_nodes; 103 104 struct btree *old_nodes[BTREE_UPDATE_NODES_MAX]; 105 __le64 old_nodes_seq[BTREE_UPDATE_NODES_MAX]; 106 unsigned nr_old_nodes; 107 108 open_bucket_idx_t open_buckets[BTREE_UPDATE_NODES_MAX * 109 BCH_REPLICAS_MAX]; 110 open_bucket_idx_t nr_open_buckets; 111 112 unsigned journal_u64s; 113 u64 journal_entries[BTREE_UPDATE_JOURNAL_RES]; 114 115 /* Only here to reduce stack usage on recursive splits: */ 116 struct keylist parent_keys; 117 /* 118 * Enough room for btree_split's keys without realloc - btree node 119 * pointers never have crc/compression info, so we only need to acount 120 * for the pointers for three keys 121 */ 122 u64 inline_keys[BKEY_BTREE_PTR_U64s_MAX * 3]; 123 }; 124 125 struct btree *__bch2_btree_node_alloc_replacement(struct btree_update *, 126 struct btree_trans *, 127 struct btree *, 128 struct bkey_format); 129 130 int bch2_btree_split_leaf(struct btree_trans *, btree_path_idx_t, unsigned); 131 132 int bch2_btree_increase_depth(struct btree_trans *, btree_path_idx_t, unsigned); 133 134 int __bch2_foreground_maybe_merge(struct btree_trans *, btree_path_idx_t, 135 unsigned, unsigned, enum btree_node_sibling); 136 137 static inline int bch2_foreground_maybe_merge_sibling(struct btree_trans *trans, 138 btree_path_idx_t path_idx, 139 unsigned level, unsigned flags, 140 enum btree_node_sibling sib) 141 { 142 struct btree_path *path = trans->paths + path_idx; 143 struct btree *b; 144 145 EBUG_ON(!btree_node_locked(path, level)); 146 147 if (bch2_btree_node_merging_disabled) 148 return 0; 149 150 b = path->l[level].b; 151 if (b->sib_u64s[sib] > trans->c->btree_foreground_merge_threshold) 152 return 0; 153 154 return __bch2_foreground_maybe_merge(trans, path_idx, level, flags, sib); 155 } 156 157 static inline int bch2_foreground_maybe_merge(struct btree_trans *trans, 158 btree_path_idx_t path, 159 unsigned level, 160 unsigned flags) 161 { 162 bch2_trans_verify_not_unlocked(trans); 163 164 return bch2_foreground_maybe_merge_sibling(trans, path, level, flags, 165 btree_prev_sib) ?: 166 bch2_foreground_maybe_merge_sibling(trans, path, level, flags, 167 btree_next_sib); 168 } 169 170 int bch2_btree_node_rewrite(struct btree_trans *, struct btree_iter *, 171 struct btree *, unsigned); 172 void bch2_btree_node_rewrite_async(struct bch_fs *, struct btree *); 173 int bch2_btree_node_update_key(struct btree_trans *, struct btree_iter *, 174 struct btree *, struct bkey_i *, 175 unsigned, bool); 176 int bch2_btree_node_update_key_get_iter(struct btree_trans *, struct btree *, 177 struct bkey_i *, unsigned, bool); 178 179 void bch2_btree_set_root_for_read(struct bch_fs *, struct btree *); 180 181 int bch2_btree_root_alloc_fake_trans(struct btree_trans *, enum btree_id, unsigned); 182 void bch2_btree_root_alloc_fake(struct bch_fs *, enum btree_id, unsigned); 183 184 static inline unsigned btree_update_reserve_required(struct bch_fs *c, 185 struct btree *b) 186 { 187 unsigned depth = btree_node_root(c, b)->c.level + 1; 188 189 /* 190 * Number of nodes we might have to allocate in a worst case btree 191 * split operation - we split all the way up to the root, then allocate 192 * a new root, unless we're already at max depth: 193 */ 194 if (depth < BTREE_MAX_DEPTH) 195 return (depth - b->c.level) * 2 + 1; 196 else 197 return (depth - b->c.level) * 2 - 1; 198 } 199 200 static inline void btree_node_reset_sib_u64s(struct btree *b) 201 { 202 b->sib_u64s[0] = b->nr.live_u64s; 203 b->sib_u64s[1] = b->nr.live_u64s; 204 } 205 206 static inline void *btree_data_end(struct btree *b) 207 { 208 return (void *) b->data + btree_buf_bytes(b); 209 } 210 211 static inline struct bkey_packed *unwritten_whiteouts_start(struct btree *b) 212 { 213 return (void *) ((u64 *) btree_data_end(b) - b->whiteout_u64s); 214 } 215 216 static inline struct bkey_packed *unwritten_whiteouts_end(struct btree *b) 217 { 218 return btree_data_end(b); 219 } 220 221 static inline void *write_block(struct btree *b) 222 { 223 return (void *) b->data + (b->written << 9); 224 } 225 226 static inline bool __btree_addr_written(struct btree *b, void *p) 227 { 228 return p < write_block(b); 229 } 230 231 static inline bool bset_written(struct btree *b, struct bset *i) 232 { 233 return __btree_addr_written(b, i); 234 } 235 236 static inline bool bkey_written(struct btree *b, struct bkey_packed *k) 237 { 238 return __btree_addr_written(b, k); 239 } 240 241 static inline ssize_t __bch2_btree_u64s_remaining(struct btree *b, void *end) 242 { 243 ssize_t used = bset_byte_offset(b, end) / sizeof(u64) + 244 b->whiteout_u64s; 245 ssize_t total = btree_buf_bytes(b) >> 3; 246 247 /* Always leave one extra u64 for bch2_varint_decode: */ 248 used++; 249 250 return total - used; 251 } 252 253 static inline size_t bch2_btree_keys_u64s_remaining(struct btree *b) 254 { 255 ssize_t remaining = __bch2_btree_u64s_remaining(b, 256 btree_bkey_last(b, bset_tree_last(b))); 257 258 BUG_ON(remaining < 0); 259 260 if (bset_written(b, btree_bset_last(b))) 261 return 0; 262 263 return remaining; 264 } 265 266 #define BTREE_WRITE_SET_U64s_BITS 9 267 268 static inline unsigned btree_write_set_buffer(struct btree *b) 269 { 270 /* 271 * Could buffer up larger amounts of keys for btrees with larger keys, 272 * pending benchmarking: 273 */ 274 return 8 << BTREE_WRITE_SET_U64s_BITS; 275 } 276 277 static inline struct btree_node_entry *want_new_bset(struct bch_fs *c, struct btree *b) 278 { 279 struct bset_tree *t = bset_tree_last(b); 280 struct btree_node_entry *bne = max(write_block(b), 281 (void *) btree_bkey_last(b, bset_tree_last(b))); 282 ssize_t remaining_space = 283 __bch2_btree_u64s_remaining(b, bne->keys.start); 284 285 if (unlikely(bset_written(b, bset(b, t)))) { 286 if (remaining_space > (ssize_t) (block_bytes(c) >> 3)) 287 return bne; 288 } else { 289 if (unlikely(bset_u64s(t) * sizeof(u64) > btree_write_set_buffer(b)) && 290 remaining_space > (ssize_t) (btree_write_set_buffer(b) >> 3)) 291 return bne; 292 } 293 294 return NULL; 295 } 296 297 static inline void push_whiteout(struct btree *b, struct bpos pos) 298 { 299 struct bkey_packed k; 300 301 BUG_ON(bch2_btree_keys_u64s_remaining(b) < BKEY_U64s); 302 EBUG_ON(btree_node_just_written(b)); 303 304 if (!bkey_pack_pos(&k, pos, b)) { 305 struct bkey *u = (void *) &k; 306 307 bkey_init(u); 308 u->p = pos; 309 } 310 311 k.needs_whiteout = true; 312 313 b->whiteout_u64s += k.u64s; 314 bkey_p_copy(unwritten_whiteouts_start(b), &k); 315 } 316 317 /* 318 * write lock must be held on @b (else the dirty bset that we were going to 319 * insert into could be written out from under us) 320 */ 321 static inline bool bch2_btree_node_insert_fits(struct btree *b, unsigned u64s) 322 { 323 if (unlikely(btree_node_need_rewrite(b))) 324 return false; 325 326 return u64s <= bch2_btree_keys_u64s_remaining(b); 327 } 328 329 void bch2_btree_updates_to_text(struct printbuf *, struct bch_fs *); 330 331 bool bch2_btree_interior_updates_flush(struct bch_fs *); 332 333 void bch2_journal_entry_to_btree_root(struct bch_fs *, struct jset_entry *); 334 struct jset_entry *bch2_btree_roots_to_journal_entries(struct bch_fs *, 335 struct jset_entry *, unsigned long); 336 337 void bch2_do_pending_node_rewrites(struct bch_fs *); 338 void bch2_free_pending_node_rewrites(struct bch_fs *); 339 340 void bch2_btree_reserve_cache_to_text(struct printbuf *, struct bch_fs *); 341 342 void bch2_fs_btree_interior_update_exit(struct bch_fs *); 343 void bch2_fs_btree_interior_update_init_early(struct bch_fs *); 344 int bch2_fs_btree_interior_update_init(struct bch_fs *); 345 346 #endif /* _BCACHEFS_BTREE_UPDATE_INTERIOR_H */ 347