| 1 | /* |
| 2 | * fs/f2fs/gc.c |
| 3 | * |
| 4 | * Copyright (c) 2012 Samsung Electronics Co., Ltd. |
| 5 | * http://www.samsung.com/ |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | */ |
| 11 | #include <linux/fs.h> |
| 12 | #include <linux/module.h> |
| 13 | #include <linux/backing-dev.h> |
| 14 | #include <linux/init.h> |
| 15 | #include <linux/f2fs_fs.h> |
| 16 | #include <linux/kthread.h> |
| 17 | #include <linux/delay.h> |
| 18 | #include <linux/freezer.h> |
| 19 | #include <linux/blkdev.h> |
| 20 | |
| 21 | #include "f2fs.h" |
| 22 | #include "node.h" |
| 23 | #include "segment.h" |
| 24 | #include "gc.h" |
| 25 | #include <trace/events/f2fs.h> |
| 26 | |
| 27 | static int gc_thread_func(void *data) |
| 28 | { |
| 29 | struct f2fs_sb_info *sbi = data; |
| 30 | struct f2fs_gc_kthread *gc_th = sbi->gc_thread; |
| 31 | wait_queue_head_t *wq = &sbi->gc_thread->gc_wait_queue_head; |
| 32 | long wait_ms; |
| 33 | |
| 34 | wait_ms = gc_th->min_sleep_time; |
| 35 | |
| 36 | do { |
| 37 | if (try_to_freeze()) |
| 38 | continue; |
| 39 | else |
| 40 | wait_event_interruptible_timeout(*wq, |
| 41 | kthread_should_stop(), |
| 42 | msecs_to_jiffies(wait_ms)); |
| 43 | if (kthread_should_stop()) |
| 44 | break; |
| 45 | |
| 46 | if (sbi->sb->s_writers.frozen >= SB_FREEZE_WRITE) { |
| 47 | increase_sleep_time(gc_th, &wait_ms); |
| 48 | continue; |
| 49 | } |
| 50 | |
| 51 | /* |
| 52 | * [GC triggering condition] |
| 53 | * 0. GC is not conducted currently. |
| 54 | * 1. There are enough dirty segments. |
| 55 | * 2. IO subsystem is idle by checking the # of writeback pages. |
| 56 | * 3. IO subsystem is idle by checking the # of requests in |
| 57 | * bdev's request list. |
| 58 | * |
| 59 | * Note) We have to avoid triggering GCs frequently. |
| 60 | * Because it is possible that some segments can be |
| 61 | * invalidated soon after by user update or deletion. |
| 62 | * So, I'd like to wait some time to collect dirty segments. |
| 63 | */ |
| 64 | if (!mutex_trylock(&sbi->gc_mutex)) |
| 65 | continue; |
| 66 | |
| 67 | if (!is_idle(sbi)) { |
| 68 | increase_sleep_time(gc_th, &wait_ms); |
| 69 | mutex_unlock(&sbi->gc_mutex); |
| 70 | continue; |
| 71 | } |
| 72 | |
| 73 | if (has_enough_invalid_blocks(sbi)) |
| 74 | decrease_sleep_time(gc_th, &wait_ms); |
| 75 | else |
| 76 | increase_sleep_time(gc_th, &wait_ms); |
| 77 | |
| 78 | stat_inc_bggc_count(sbi); |
| 79 | |
| 80 | /* if return value is not zero, no victim was selected */ |
| 81 | if (f2fs_gc(sbi)) |
| 82 | wait_ms = gc_th->no_gc_sleep_time; |
| 83 | |
| 84 | /* balancing f2fs's metadata periodically */ |
| 85 | f2fs_balance_fs_bg(sbi); |
| 86 | |
| 87 | } while (!kthread_should_stop()); |
| 88 | return 0; |
| 89 | } |
| 90 | |
| 91 | int start_gc_thread(struct f2fs_sb_info *sbi) |
| 92 | { |
| 93 | struct f2fs_gc_kthread *gc_th; |
| 94 | dev_t dev = sbi->sb->s_bdev->bd_dev; |
| 95 | int err = 0; |
| 96 | |
| 97 | gc_th = kmalloc(sizeof(struct f2fs_gc_kthread), GFP_KERNEL); |
| 98 | if (!gc_th) { |
| 99 | err = -ENOMEM; |
| 100 | goto out; |
| 101 | } |
| 102 | |
| 103 | gc_th->min_sleep_time = DEF_GC_THREAD_MIN_SLEEP_TIME; |
| 104 | gc_th->max_sleep_time = DEF_GC_THREAD_MAX_SLEEP_TIME; |
| 105 | gc_th->no_gc_sleep_time = DEF_GC_THREAD_NOGC_SLEEP_TIME; |
| 106 | |
| 107 | gc_th->gc_idle = 0; |
| 108 | |
| 109 | sbi->gc_thread = gc_th; |
| 110 | init_waitqueue_head(&sbi->gc_thread->gc_wait_queue_head); |
| 111 | sbi->gc_thread->f2fs_gc_task = kthread_run(gc_thread_func, sbi, |
| 112 | "f2fs_gc-%u:%u", MAJOR(dev), MINOR(dev)); |
| 113 | if (IS_ERR(gc_th->f2fs_gc_task)) { |
| 114 | err = PTR_ERR(gc_th->f2fs_gc_task); |
| 115 | kfree(gc_th); |
| 116 | sbi->gc_thread = NULL; |
| 117 | } |
| 118 | out: |
| 119 | return err; |
| 120 | } |
| 121 | |
| 122 | void stop_gc_thread(struct f2fs_sb_info *sbi) |
| 123 | { |
| 124 | struct f2fs_gc_kthread *gc_th = sbi->gc_thread; |
| 125 | if (!gc_th) |
| 126 | return; |
| 127 | kthread_stop(gc_th->f2fs_gc_task); |
| 128 | kfree(gc_th); |
| 129 | sbi->gc_thread = NULL; |
| 130 | } |
| 131 | |
| 132 | static int select_gc_type(struct f2fs_gc_kthread *gc_th, int gc_type) |
| 133 | { |
| 134 | int gc_mode = (gc_type == BG_GC) ? GC_CB : GC_GREEDY; |
| 135 | |
| 136 | if (gc_th && gc_th->gc_idle) { |
| 137 | if (gc_th->gc_idle == 1) |
| 138 | gc_mode = GC_CB; |
| 139 | else if (gc_th->gc_idle == 2) |
| 140 | gc_mode = GC_GREEDY; |
| 141 | } |
| 142 | return gc_mode; |
| 143 | } |
| 144 | |
| 145 | static void select_policy(struct f2fs_sb_info *sbi, int gc_type, |
| 146 | int type, struct victim_sel_policy *p) |
| 147 | { |
| 148 | struct dirty_seglist_info *dirty_i = DIRTY_I(sbi); |
| 149 | |
| 150 | if (p->alloc_mode == SSR) { |
| 151 | p->gc_mode = GC_GREEDY; |
| 152 | p->dirty_segmap = dirty_i->dirty_segmap[type]; |
| 153 | p->max_search = dirty_i->nr_dirty[type]; |
| 154 | p->ofs_unit = 1; |
| 155 | } else { |
| 156 | p->gc_mode = select_gc_type(sbi->gc_thread, gc_type); |
| 157 | p->dirty_segmap = dirty_i->dirty_segmap[DIRTY]; |
| 158 | p->max_search = dirty_i->nr_dirty[DIRTY]; |
| 159 | p->ofs_unit = sbi->segs_per_sec; |
| 160 | } |
| 161 | |
| 162 | if (p->max_search > sbi->max_victim_search) |
| 163 | p->max_search = sbi->max_victim_search; |
| 164 | |
| 165 | p->offset = sbi->last_victim[p->gc_mode]; |
| 166 | } |
| 167 | |
| 168 | static unsigned int get_max_cost(struct f2fs_sb_info *sbi, |
| 169 | struct victim_sel_policy *p) |
| 170 | { |
| 171 | /* SSR allocates in a segment unit */ |
| 172 | if (p->alloc_mode == SSR) |
| 173 | return 1 << sbi->log_blocks_per_seg; |
| 174 | if (p->gc_mode == GC_GREEDY) |
| 175 | return (1 << sbi->log_blocks_per_seg) * p->ofs_unit; |
| 176 | else if (p->gc_mode == GC_CB) |
| 177 | return UINT_MAX; |
| 178 | else /* No other gc_mode */ |
| 179 | return 0; |
| 180 | } |
| 181 | |
| 182 | static unsigned int check_bg_victims(struct f2fs_sb_info *sbi) |
| 183 | { |
| 184 | struct dirty_seglist_info *dirty_i = DIRTY_I(sbi); |
| 185 | unsigned int secno; |
| 186 | |
| 187 | /* |
| 188 | * If the gc_type is FG_GC, we can select victim segments |
| 189 | * selected by background GC before. |
| 190 | * Those segments guarantee they have small valid blocks. |
| 191 | */ |
| 192 | for_each_set_bit(secno, dirty_i->victim_secmap, MAIN_SECS(sbi)) { |
| 193 | if (sec_usage_check(sbi, secno)) |
| 194 | continue; |
| 195 | clear_bit(secno, dirty_i->victim_secmap); |
| 196 | return secno * sbi->segs_per_sec; |
| 197 | } |
| 198 | return NULL_SEGNO; |
| 199 | } |
| 200 | |
| 201 | static unsigned int get_cb_cost(struct f2fs_sb_info *sbi, unsigned int segno) |
| 202 | { |
| 203 | struct sit_info *sit_i = SIT_I(sbi); |
| 204 | unsigned int secno = GET_SECNO(sbi, segno); |
| 205 | unsigned int start = secno * sbi->segs_per_sec; |
| 206 | unsigned long long mtime = 0; |
| 207 | unsigned int vblocks; |
| 208 | unsigned char age = 0; |
| 209 | unsigned char u; |
| 210 | unsigned int i; |
| 211 | |
| 212 | for (i = 0; i < sbi->segs_per_sec; i++) |
| 213 | mtime += get_seg_entry(sbi, start + i)->mtime; |
| 214 | vblocks = get_valid_blocks(sbi, segno, sbi->segs_per_sec); |
| 215 | |
| 216 | mtime = div_u64(mtime, sbi->segs_per_sec); |
| 217 | vblocks = div_u64(vblocks, sbi->segs_per_sec); |
| 218 | |
| 219 | u = (vblocks * 100) >> sbi->log_blocks_per_seg; |
| 220 | |
| 221 | /* Handle if the system time has changed by the user */ |
| 222 | if (mtime < sit_i->min_mtime) |
| 223 | sit_i->min_mtime = mtime; |
| 224 | if (mtime > sit_i->max_mtime) |
| 225 | sit_i->max_mtime = mtime; |
| 226 | if (sit_i->max_mtime != sit_i->min_mtime) |
| 227 | age = 100 - div64_u64(100 * (mtime - sit_i->min_mtime), |
| 228 | sit_i->max_mtime - sit_i->min_mtime); |
| 229 | |
| 230 | return UINT_MAX - ((100 * (100 - u) * age) / (100 + u)); |
| 231 | } |
| 232 | |
| 233 | static inline unsigned int get_gc_cost(struct f2fs_sb_info *sbi, |
| 234 | unsigned int segno, struct victim_sel_policy *p) |
| 235 | { |
| 236 | if (p->alloc_mode == SSR) |
| 237 | return get_seg_entry(sbi, segno)->ckpt_valid_blocks; |
| 238 | |
| 239 | /* alloc_mode == LFS */ |
| 240 | if (p->gc_mode == GC_GREEDY) |
| 241 | return get_valid_blocks(sbi, segno, sbi->segs_per_sec); |
| 242 | else |
| 243 | return get_cb_cost(sbi, segno); |
| 244 | } |
| 245 | |
| 246 | /* |
| 247 | * This function is called from two paths. |
| 248 | * One is garbage collection and the other is SSR segment selection. |
| 249 | * When it is called during GC, it just gets a victim segment |
| 250 | * and it does not remove it from dirty seglist. |
| 251 | * When it is called from SSR segment selection, it finds a segment |
| 252 | * which has minimum valid blocks and removes it from dirty seglist. |
| 253 | */ |
| 254 | static int get_victim_by_default(struct f2fs_sb_info *sbi, |
| 255 | unsigned int *result, int gc_type, int type, char alloc_mode) |
| 256 | { |
| 257 | struct dirty_seglist_info *dirty_i = DIRTY_I(sbi); |
| 258 | struct victim_sel_policy p; |
| 259 | unsigned int secno, max_cost; |
| 260 | int nsearched = 0; |
| 261 | |
| 262 | mutex_lock(&dirty_i->seglist_lock); |
| 263 | |
| 264 | p.alloc_mode = alloc_mode; |
| 265 | select_policy(sbi, gc_type, type, &p); |
| 266 | |
| 267 | p.min_segno = NULL_SEGNO; |
| 268 | p.min_cost = max_cost = get_max_cost(sbi, &p); |
| 269 | |
| 270 | if (p.alloc_mode == LFS && gc_type == FG_GC) { |
| 271 | p.min_segno = check_bg_victims(sbi); |
| 272 | if (p.min_segno != NULL_SEGNO) |
| 273 | goto got_it; |
| 274 | } |
| 275 | |
| 276 | while (1) { |
| 277 | unsigned long cost; |
| 278 | unsigned int segno; |
| 279 | |
| 280 | segno = find_next_bit(p.dirty_segmap, MAIN_SEGS(sbi), p.offset); |
| 281 | if (segno >= MAIN_SEGS(sbi)) { |
| 282 | if (sbi->last_victim[p.gc_mode]) { |
| 283 | sbi->last_victim[p.gc_mode] = 0; |
| 284 | p.offset = 0; |
| 285 | continue; |
| 286 | } |
| 287 | break; |
| 288 | } |
| 289 | |
| 290 | p.offset = segno + p.ofs_unit; |
| 291 | if (p.ofs_unit > 1) |
| 292 | p.offset -= segno % p.ofs_unit; |
| 293 | |
| 294 | secno = GET_SECNO(sbi, segno); |
| 295 | |
| 296 | if (sec_usage_check(sbi, secno)) |
| 297 | continue; |
| 298 | if (gc_type == BG_GC && test_bit(secno, dirty_i->victim_secmap)) |
| 299 | continue; |
| 300 | |
| 301 | cost = get_gc_cost(sbi, segno, &p); |
| 302 | |
| 303 | if (p.min_cost > cost) { |
| 304 | p.min_segno = segno; |
| 305 | p.min_cost = cost; |
| 306 | } else if (unlikely(cost == max_cost)) { |
| 307 | continue; |
| 308 | } |
| 309 | |
| 310 | if (nsearched++ >= p.max_search) { |
| 311 | sbi->last_victim[p.gc_mode] = segno; |
| 312 | break; |
| 313 | } |
| 314 | } |
| 315 | if (p.min_segno != NULL_SEGNO) { |
| 316 | got_it: |
| 317 | if (p.alloc_mode == LFS) { |
| 318 | secno = GET_SECNO(sbi, p.min_segno); |
| 319 | if (gc_type == FG_GC) |
| 320 | sbi->cur_victim_sec = secno; |
| 321 | else |
| 322 | set_bit(secno, dirty_i->victim_secmap); |
| 323 | } |
| 324 | *result = (p.min_segno / p.ofs_unit) * p.ofs_unit; |
| 325 | |
| 326 | trace_f2fs_get_victim(sbi->sb, type, gc_type, &p, |
| 327 | sbi->cur_victim_sec, |
| 328 | prefree_segments(sbi), free_segments(sbi)); |
| 329 | } |
| 330 | mutex_unlock(&dirty_i->seglist_lock); |
| 331 | |
| 332 | return (p.min_segno == NULL_SEGNO) ? 0 : 1; |
| 333 | } |
| 334 | |
| 335 | static const struct victim_selection default_v_ops = { |
| 336 | .get_victim = get_victim_by_default, |
| 337 | }; |
| 338 | |
| 339 | static struct inode *find_gc_inode(struct gc_inode_list *gc_list, nid_t ino) |
| 340 | { |
| 341 | struct inode_entry *ie; |
| 342 | |
| 343 | ie = radix_tree_lookup(&gc_list->iroot, ino); |
| 344 | if (ie) |
| 345 | return ie->inode; |
| 346 | return NULL; |
| 347 | } |
| 348 | |
| 349 | static void add_gc_inode(struct gc_inode_list *gc_list, struct inode *inode) |
| 350 | { |
| 351 | struct inode_entry *new_ie; |
| 352 | |
| 353 | if (inode == find_gc_inode(gc_list, inode->i_ino)) { |
| 354 | iput(inode); |
| 355 | return; |
| 356 | } |
| 357 | new_ie = f2fs_kmem_cache_alloc(inode_entry_slab, GFP_NOFS); |
| 358 | new_ie->inode = inode; |
| 359 | |
| 360 | f2fs_radix_tree_insert(&gc_list->iroot, inode->i_ino, new_ie); |
| 361 | list_add_tail(&new_ie->list, &gc_list->ilist); |
| 362 | } |
| 363 | |
| 364 | static void put_gc_inode(struct gc_inode_list *gc_list) |
| 365 | { |
| 366 | struct inode_entry *ie, *next_ie; |
| 367 | list_for_each_entry_safe(ie, next_ie, &gc_list->ilist, list) { |
| 368 | radix_tree_delete(&gc_list->iroot, ie->inode->i_ino); |
| 369 | iput(ie->inode); |
| 370 | list_del(&ie->list); |
| 371 | kmem_cache_free(inode_entry_slab, ie); |
| 372 | } |
| 373 | } |
| 374 | |
| 375 | static int check_valid_map(struct f2fs_sb_info *sbi, |
| 376 | unsigned int segno, int offset) |
| 377 | { |
| 378 | struct sit_info *sit_i = SIT_I(sbi); |
| 379 | struct seg_entry *sentry; |
| 380 | int ret; |
| 381 | |
| 382 | mutex_lock(&sit_i->sentry_lock); |
| 383 | sentry = get_seg_entry(sbi, segno); |
| 384 | ret = f2fs_test_bit(offset, sentry->cur_valid_map); |
| 385 | mutex_unlock(&sit_i->sentry_lock); |
| 386 | return ret; |
| 387 | } |
| 388 | |
| 389 | /* |
| 390 | * This function compares node address got in summary with that in NAT. |
| 391 | * On validity, copy that node with cold status, otherwise (invalid node) |
| 392 | * ignore that. |
| 393 | */ |
| 394 | static void gc_node_segment(struct f2fs_sb_info *sbi, |
| 395 | struct f2fs_summary *sum, unsigned int segno, int gc_type) |
| 396 | { |
| 397 | bool initial = true; |
| 398 | struct f2fs_summary *entry; |
| 399 | int off; |
| 400 | |
| 401 | next_step: |
| 402 | entry = sum; |
| 403 | |
| 404 | for (off = 0; off < sbi->blocks_per_seg; off++, entry++) { |
| 405 | nid_t nid = le32_to_cpu(entry->nid); |
| 406 | struct page *node_page; |
| 407 | |
| 408 | /* stop BG_GC if there is not enough free sections. */ |
| 409 | if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0)) |
| 410 | return; |
| 411 | |
| 412 | if (check_valid_map(sbi, segno, off) == 0) |
| 413 | continue; |
| 414 | |
| 415 | if (initial) { |
| 416 | ra_node_page(sbi, nid); |
| 417 | continue; |
| 418 | } |
| 419 | node_page = get_node_page(sbi, nid); |
| 420 | if (IS_ERR(node_page)) |
| 421 | continue; |
| 422 | |
| 423 | /* block may become invalid during get_node_page */ |
| 424 | if (check_valid_map(sbi, segno, off) == 0) { |
| 425 | f2fs_put_page(node_page, 1); |
| 426 | continue; |
| 427 | } |
| 428 | |
| 429 | /* set page dirty and write it */ |
| 430 | if (gc_type == FG_GC) { |
| 431 | f2fs_wait_on_page_writeback(node_page, NODE); |
| 432 | set_page_dirty(node_page); |
| 433 | } else { |
| 434 | if (!PageWriteback(node_page)) |
| 435 | set_page_dirty(node_page); |
| 436 | } |
| 437 | f2fs_put_page(node_page, 1); |
| 438 | stat_inc_node_blk_count(sbi, 1, gc_type); |
| 439 | } |
| 440 | |
| 441 | if (initial) { |
| 442 | initial = false; |
| 443 | goto next_step; |
| 444 | } |
| 445 | |
| 446 | if (gc_type == FG_GC) { |
| 447 | struct writeback_control wbc = { |
| 448 | .sync_mode = WB_SYNC_ALL, |
| 449 | .nr_to_write = LONG_MAX, |
| 450 | .for_reclaim = 0, |
| 451 | }; |
| 452 | sync_node_pages(sbi, 0, &wbc); |
| 453 | |
| 454 | /* |
| 455 | * In the case of FG_GC, it'd be better to reclaim this victim |
| 456 | * completely. |
| 457 | */ |
| 458 | if (get_valid_blocks(sbi, segno, 1) != 0) |
| 459 | goto next_step; |
| 460 | } |
| 461 | } |
| 462 | |
| 463 | /* |
| 464 | * Calculate start block index indicating the given node offset. |
| 465 | * Be careful, caller should give this node offset only indicating direct node |
| 466 | * blocks. If any node offsets, which point the other types of node blocks such |
| 467 | * as indirect or double indirect node blocks, are given, it must be a caller's |
| 468 | * bug. |
| 469 | */ |
| 470 | block_t start_bidx_of_node(unsigned int node_ofs, struct f2fs_inode_info *fi) |
| 471 | { |
| 472 | unsigned int indirect_blks = 2 * NIDS_PER_BLOCK + 4; |
| 473 | unsigned int bidx; |
| 474 | |
| 475 | if (node_ofs == 0) |
| 476 | return 0; |
| 477 | |
| 478 | if (node_ofs <= 2) { |
| 479 | bidx = node_ofs - 1; |
| 480 | } else if (node_ofs <= indirect_blks) { |
| 481 | int dec = (node_ofs - 4) / (NIDS_PER_BLOCK + 1); |
| 482 | bidx = node_ofs - 2 - dec; |
| 483 | } else { |
| 484 | int dec = (node_ofs - indirect_blks - 3) / (NIDS_PER_BLOCK + 1); |
| 485 | bidx = node_ofs - 5 - dec; |
| 486 | } |
| 487 | return bidx * ADDRS_PER_BLOCK + ADDRS_PER_INODE(fi); |
| 488 | } |
| 489 | |
| 490 | static int check_dnode(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, |
| 491 | struct node_info *dni, block_t blkaddr, unsigned int *nofs) |
| 492 | { |
| 493 | struct page *node_page; |
| 494 | nid_t nid; |
| 495 | unsigned int ofs_in_node; |
| 496 | block_t source_blkaddr; |
| 497 | |
| 498 | nid = le32_to_cpu(sum->nid); |
| 499 | ofs_in_node = le16_to_cpu(sum->ofs_in_node); |
| 500 | |
| 501 | node_page = get_node_page(sbi, nid); |
| 502 | if (IS_ERR(node_page)) |
| 503 | return 0; |
| 504 | |
| 505 | get_node_info(sbi, nid, dni); |
| 506 | |
| 507 | if (sum->version != dni->version) { |
| 508 | f2fs_put_page(node_page, 1); |
| 509 | return 0; |
| 510 | } |
| 511 | |
| 512 | *nofs = ofs_of_node(node_page); |
| 513 | source_blkaddr = datablock_addr(node_page, ofs_in_node); |
| 514 | f2fs_put_page(node_page, 1); |
| 515 | |
| 516 | if (source_blkaddr != blkaddr) |
| 517 | return 0; |
| 518 | return 1; |
| 519 | } |
| 520 | |
| 521 | static void move_encrypted_block(struct inode *inode, block_t bidx) |
| 522 | { |
| 523 | struct f2fs_io_info fio = { |
| 524 | .sbi = F2FS_I_SB(inode), |
| 525 | .type = DATA, |
| 526 | .rw = READ_SYNC, |
| 527 | .encrypted_page = NULL, |
| 528 | }; |
| 529 | struct dnode_of_data dn; |
| 530 | struct f2fs_summary sum; |
| 531 | struct node_info ni; |
| 532 | struct page *page; |
| 533 | int err; |
| 534 | |
| 535 | /* do not read out */ |
| 536 | page = grab_cache_page(inode->i_mapping, bidx); |
| 537 | if (!page) |
| 538 | return; |
| 539 | |
| 540 | set_new_dnode(&dn, inode, NULL, NULL, 0); |
| 541 | err = get_dnode_of_data(&dn, bidx, LOOKUP_NODE); |
| 542 | if (err) |
| 543 | goto out; |
| 544 | |
| 545 | if (unlikely(dn.data_blkaddr == NULL_ADDR)) |
| 546 | goto put_out; |
| 547 | |
| 548 | get_node_info(fio.sbi, dn.nid, &ni); |
| 549 | set_summary(&sum, dn.nid, dn.ofs_in_node, ni.version); |
| 550 | |
| 551 | /* read page */ |
| 552 | fio.page = page; |
| 553 | fio.blk_addr = dn.data_blkaddr; |
| 554 | |
| 555 | fio.encrypted_page = grab_cache_page(META_MAPPING(fio.sbi), fio.blk_addr); |
| 556 | if (!fio.encrypted_page) |
| 557 | goto put_out; |
| 558 | |
| 559 | err = f2fs_submit_page_bio(&fio); |
| 560 | if (err) |
| 561 | goto put_page_out; |
| 562 | |
| 563 | /* write page */ |
| 564 | lock_page(fio.encrypted_page); |
| 565 | |
| 566 | if (unlikely(!PageUptodate(fio.encrypted_page))) |
| 567 | goto put_page_out; |
| 568 | if (unlikely(fio.encrypted_page->mapping != META_MAPPING(fio.sbi))) |
| 569 | goto put_page_out; |
| 570 | |
| 571 | set_page_writeback(fio.encrypted_page); |
| 572 | |
| 573 | /* allocate block address */ |
| 574 | f2fs_wait_on_page_writeback(dn.node_page, NODE); |
| 575 | allocate_data_block(fio.sbi, NULL, fio.blk_addr, |
| 576 | &fio.blk_addr, &sum, CURSEG_COLD_DATA); |
| 577 | fio.rw = WRITE_SYNC; |
| 578 | f2fs_submit_page_mbio(&fio); |
| 579 | |
| 580 | dn.data_blkaddr = fio.blk_addr; |
| 581 | set_data_blkaddr(&dn); |
| 582 | f2fs_update_extent_cache(&dn); |
| 583 | set_inode_flag(F2FS_I(inode), FI_APPEND_WRITE); |
| 584 | if (page->index == 0) |
| 585 | set_inode_flag(F2FS_I(inode), FI_FIRST_BLOCK_WRITTEN); |
| 586 | put_page_out: |
| 587 | f2fs_put_page(fio.encrypted_page, 1); |
| 588 | put_out: |
| 589 | f2fs_put_dnode(&dn); |
| 590 | out: |
| 591 | f2fs_put_page(page, 1); |
| 592 | } |
| 593 | |
| 594 | static void move_data_page(struct inode *inode, block_t bidx, int gc_type) |
| 595 | { |
| 596 | struct page *page; |
| 597 | |
| 598 | page = get_lock_data_page(inode, bidx); |
| 599 | if (IS_ERR(page)) |
| 600 | return; |
| 601 | |
| 602 | if (gc_type == BG_GC) { |
| 603 | if (PageWriteback(page)) |
| 604 | goto out; |
| 605 | set_page_dirty(page); |
| 606 | set_cold_data(page); |
| 607 | } else { |
| 608 | struct f2fs_io_info fio = { |
| 609 | .sbi = F2FS_I_SB(inode), |
| 610 | .type = DATA, |
| 611 | .rw = WRITE_SYNC, |
| 612 | .page = page, |
| 613 | .encrypted_page = NULL, |
| 614 | }; |
| 615 | f2fs_wait_on_page_writeback(page, DATA); |
| 616 | |
| 617 | if (clear_page_dirty_for_io(page)) |
| 618 | inode_dec_dirty_pages(inode); |
| 619 | set_cold_data(page); |
| 620 | do_write_data_page(&fio); |
| 621 | clear_cold_data(page); |
| 622 | } |
| 623 | out: |
| 624 | f2fs_put_page(page, 1); |
| 625 | } |
| 626 | |
| 627 | /* |
| 628 | * This function tries to get parent node of victim data block, and identifies |
| 629 | * data block validity. If the block is valid, copy that with cold status and |
| 630 | * modify parent node. |
| 631 | * If the parent node is not valid or the data block address is different, |
| 632 | * the victim data block is ignored. |
| 633 | */ |
| 634 | static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, |
| 635 | struct gc_inode_list *gc_list, unsigned int segno, int gc_type) |
| 636 | { |
| 637 | struct super_block *sb = sbi->sb; |
| 638 | struct f2fs_summary *entry; |
| 639 | block_t start_addr; |
| 640 | int off; |
| 641 | int phase = 0; |
| 642 | |
| 643 | start_addr = START_BLOCK(sbi, segno); |
| 644 | |
| 645 | next_step: |
| 646 | entry = sum; |
| 647 | |
| 648 | for (off = 0; off < sbi->blocks_per_seg; off++, entry++) { |
| 649 | struct page *data_page; |
| 650 | struct inode *inode; |
| 651 | struct node_info dni; /* dnode info for the data */ |
| 652 | unsigned int ofs_in_node, nofs; |
| 653 | block_t start_bidx; |
| 654 | |
| 655 | /* stop BG_GC if there is not enough free sections. */ |
| 656 | if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0)) |
| 657 | return; |
| 658 | |
| 659 | if (check_valid_map(sbi, segno, off) == 0) |
| 660 | continue; |
| 661 | |
| 662 | if (phase == 0) { |
| 663 | ra_node_page(sbi, le32_to_cpu(entry->nid)); |
| 664 | continue; |
| 665 | } |
| 666 | |
| 667 | /* Get an inode by ino with checking validity */ |
| 668 | if (check_dnode(sbi, entry, &dni, start_addr + off, &nofs) == 0) |
| 669 | continue; |
| 670 | |
| 671 | if (phase == 1) { |
| 672 | ra_node_page(sbi, dni.ino); |
| 673 | continue; |
| 674 | } |
| 675 | |
| 676 | ofs_in_node = le16_to_cpu(entry->ofs_in_node); |
| 677 | |
| 678 | if (phase == 2) { |
| 679 | inode = f2fs_iget(sb, dni.ino); |
| 680 | if (IS_ERR(inode) || is_bad_inode(inode)) |
| 681 | continue; |
| 682 | |
| 683 | /* if encrypted inode, let's go phase 3 */ |
| 684 | if (f2fs_encrypted_inode(inode) && |
| 685 | S_ISREG(inode->i_mode)) { |
| 686 | add_gc_inode(gc_list, inode); |
| 687 | continue; |
| 688 | } |
| 689 | |
| 690 | start_bidx = start_bidx_of_node(nofs, F2FS_I(inode)); |
| 691 | data_page = get_read_data_page(inode, |
| 692 | start_bidx + ofs_in_node, READA); |
| 693 | if (IS_ERR(data_page)) { |
| 694 | iput(inode); |
| 695 | continue; |
| 696 | } |
| 697 | |
| 698 | f2fs_put_page(data_page, 0); |
| 699 | add_gc_inode(gc_list, inode); |
| 700 | continue; |
| 701 | } |
| 702 | |
| 703 | /* phase 3 */ |
| 704 | inode = find_gc_inode(gc_list, dni.ino); |
| 705 | if (inode) { |
| 706 | start_bidx = start_bidx_of_node(nofs, F2FS_I(inode)) |
| 707 | + ofs_in_node; |
| 708 | if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) |
| 709 | move_encrypted_block(inode, start_bidx); |
| 710 | else |
| 711 | move_data_page(inode, start_bidx, gc_type); |
| 712 | stat_inc_data_blk_count(sbi, 1, gc_type); |
| 713 | } |
| 714 | } |
| 715 | |
| 716 | if (++phase < 4) |
| 717 | goto next_step; |
| 718 | |
| 719 | if (gc_type == FG_GC) { |
| 720 | f2fs_submit_merged_bio(sbi, DATA, WRITE); |
| 721 | |
| 722 | /* |
| 723 | * In the case of FG_GC, it'd be better to reclaim this victim |
| 724 | * completely. |
| 725 | */ |
| 726 | if (get_valid_blocks(sbi, segno, 1) != 0) { |
| 727 | phase = 2; |
| 728 | goto next_step; |
| 729 | } |
| 730 | } |
| 731 | } |
| 732 | |
| 733 | static int __get_victim(struct f2fs_sb_info *sbi, unsigned int *victim, |
| 734 | int gc_type) |
| 735 | { |
| 736 | struct sit_info *sit_i = SIT_I(sbi); |
| 737 | int ret; |
| 738 | |
| 739 | mutex_lock(&sit_i->sentry_lock); |
| 740 | ret = DIRTY_I(sbi)->v_ops->get_victim(sbi, victim, gc_type, |
| 741 | NO_CHECK_TYPE, LFS); |
| 742 | mutex_unlock(&sit_i->sentry_lock); |
| 743 | return ret; |
| 744 | } |
| 745 | |
| 746 | static void do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno, |
| 747 | struct gc_inode_list *gc_list, int gc_type) |
| 748 | { |
| 749 | struct page *sum_page; |
| 750 | struct f2fs_summary_block *sum; |
| 751 | struct blk_plug plug; |
| 752 | |
| 753 | /* read segment summary of victim */ |
| 754 | sum_page = get_sum_page(sbi, segno); |
| 755 | |
| 756 | blk_start_plug(&plug); |
| 757 | |
| 758 | sum = page_address(sum_page); |
| 759 | |
| 760 | /* |
| 761 | * this is to avoid deadlock: |
| 762 | * - lock_page(sum_page) - f2fs_replace_block |
| 763 | * - check_valid_map() - mutex_lock(sentry_lock) |
| 764 | * - mutex_lock(sentry_lock) - change_curseg() |
| 765 | * - lock_page(sum_page) |
| 766 | */ |
| 767 | unlock_page(sum_page); |
| 768 | |
| 769 | switch (GET_SUM_TYPE((&sum->footer))) { |
| 770 | case SUM_TYPE_NODE: |
| 771 | gc_node_segment(sbi, sum->entries, segno, gc_type); |
| 772 | break; |
| 773 | case SUM_TYPE_DATA: |
| 774 | gc_data_segment(sbi, sum->entries, gc_list, segno, gc_type); |
| 775 | break; |
| 776 | } |
| 777 | blk_finish_plug(&plug); |
| 778 | |
| 779 | stat_inc_seg_count(sbi, GET_SUM_TYPE((&sum->footer)), gc_type); |
| 780 | stat_inc_call_count(sbi->stat_info); |
| 781 | |
| 782 | f2fs_put_page(sum_page, 0); |
| 783 | } |
| 784 | |
| 785 | int f2fs_gc(struct f2fs_sb_info *sbi) |
| 786 | { |
| 787 | unsigned int segno, i; |
| 788 | int gc_type = BG_GC; |
| 789 | int nfree = 0; |
| 790 | int ret = -1; |
| 791 | struct cp_control cpc; |
| 792 | struct gc_inode_list gc_list = { |
| 793 | .ilist = LIST_HEAD_INIT(gc_list.ilist), |
| 794 | .iroot = RADIX_TREE_INIT(GFP_NOFS), |
| 795 | }; |
| 796 | |
| 797 | cpc.reason = __get_cp_reason(sbi); |
| 798 | gc_more: |
| 799 | if (unlikely(!(sbi->sb->s_flags & MS_ACTIVE))) |
| 800 | goto stop; |
| 801 | if (unlikely(f2fs_cp_error(sbi))) |
| 802 | goto stop; |
| 803 | |
| 804 | if (gc_type == BG_GC && has_not_enough_free_secs(sbi, nfree)) { |
| 805 | gc_type = FG_GC; |
| 806 | write_checkpoint(sbi, &cpc); |
| 807 | } |
| 808 | |
| 809 | if (!__get_victim(sbi, &segno, gc_type)) |
| 810 | goto stop; |
| 811 | ret = 0; |
| 812 | |
| 813 | /* readahead multi ssa blocks those have contiguous address */ |
| 814 | if (sbi->segs_per_sec > 1) |
| 815 | ra_meta_pages(sbi, GET_SUM_BLOCK(sbi, segno), sbi->segs_per_sec, |
| 816 | META_SSA); |
| 817 | |
| 818 | for (i = 0; i < sbi->segs_per_sec; i++) |
| 819 | do_garbage_collect(sbi, segno + i, &gc_list, gc_type); |
| 820 | |
| 821 | if (gc_type == FG_GC) { |
| 822 | sbi->cur_victim_sec = NULL_SEGNO; |
| 823 | nfree++; |
| 824 | WARN_ON(get_valid_blocks(sbi, segno, sbi->segs_per_sec)); |
| 825 | } |
| 826 | |
| 827 | if (has_not_enough_free_secs(sbi, nfree)) |
| 828 | goto gc_more; |
| 829 | |
| 830 | if (gc_type == FG_GC) |
| 831 | write_checkpoint(sbi, &cpc); |
| 832 | stop: |
| 833 | mutex_unlock(&sbi->gc_mutex); |
| 834 | |
| 835 | put_gc_inode(&gc_list); |
| 836 | return ret; |
| 837 | } |
| 838 | |
| 839 | void build_gc_manager(struct f2fs_sb_info *sbi) |
| 840 | { |
| 841 | DIRTY_I(sbi)->v_ops = &default_v_ops; |
| 842 | } |