git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/move.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include "bcachefs.h"
   4 #include "alloc_background.h"
   5 #include "alloc_foreground.h"
   6 #include "backpointers.h"
   7 #include "bkey_buf.h"
   8 #include "btree_gc.h"
   9 #include "btree_update.h"
  10 #include "btree_update_interior.h"
  11 #include "btree_write_buffer.h"
  12 #include "disk_groups.h"
  13 #include "ec.h"
  14 #include "errcode.h"
  15 #include "error.h"
  16 #include "inode.h"
  17 #include "io_read.h"
  18 #include "io_write.h"
  19 #include "journal_reclaim.h"
  20 #include "keylist.h"
  21 #include "move.h"
  22 #include "replicas.h"
  23 #include "snapshot.h"
  24 #include "super-io.h"
  25 #include "trace.h"
  26
  27 #include <linux/ioprio.h>
  28 #include <linux/kthread.h>
  29
  30 const char * const bch2_data_ops_strs[] = {
  31 #define x(t, n, ...) [n] = #t,
  32         BCH_DATA_OPS()
  33 #undef x
  34         NULL
  35 };
  36
  37 static void trace_move_extent2(struct bch_fs *c, struct bkey_s_c k)
  38 {
  39         if (trace_move_extent_enabled()) {
  40                 struct printbuf buf = PRINTBUF;
  41
  42                 bch2_bkey_val_to_text(&buf, c, k);
  43                 trace_move_extent(c, buf.buf);
  44                 printbuf_exit(&buf);
  45         }
  46 }
  47
  48 static void trace_move_extent_read2(struct bch_fs *c, struct bkey_s_c k)
  49 {
  50         if (trace_move_extent_read_enabled()) {
  51                 struct printbuf buf = PRINTBUF;
  52
  53                 bch2_bkey_val_to_text(&buf, c, k);
  54                 trace_move_extent_read(c, buf.buf);
  55                 printbuf_exit(&buf);
  56         }
  57 }
  58
  59 struct moving_io {
  60         struct list_head                read_list;
  61         struct list_head                io_list;
  62         struct move_bucket_in_flight    *b;
  63         struct closure                  cl;
  64         bool                            read_completed;
  65
  66         unsigned                        read_sectors;
  67         unsigned                        write_sectors;
  68
  69         struct bch_read_bio             rbio;
  70
  71         struct data_update              write;
  72         /* Must be last since it is variable size */
  73         struct bio_vec                  bi_inline_vecs[];
  74 };
  75
  76 static void move_free(struct moving_io *io)
  77 {
  78         struct moving_context *ctxt = io->write.ctxt;
  79
  80         if (io->b)
  81                 atomic_dec(&io->b->count);
  82
  83         bch2_data_update_exit(&io->write);
  84
  85         mutex_lock(&ctxt->lock);
  86         list_del(&io->io_list);
  87         wake_up(&ctxt->wait);
  88         mutex_unlock(&ctxt->lock);
  89
  90         kfree(io);
  91 }
  92
  93 static void move_write_done(struct bch_write_op *op)
  94 {
  95         struct moving_io *io = container_of(op, struct moving_io, write.op);
  96         struct moving_context *ctxt = io->write.ctxt;
  97
  98         if (io->write.op.error)
  99                 ctxt->write_error = true;
 100
 101         atomic_sub(io->write_sectors, &io->write.ctxt->write_sectors);
 102         atomic_dec(&io->write.ctxt->write_ios);
 103         move_free(io);
 104         closure_put(&ctxt->cl);
 105 }
 106
 107 static void move_write(struct moving_io *io)
 108 {
 109         if (unlikely(io->rbio.bio.bi_status || io->rbio.hole)) {
 110                 move_free(io);
 111                 return;
 112         }
 113
 114         closure_get(&io->write.ctxt->cl);
 115         atomic_add(io->write_sectors, &io->write.ctxt->write_sectors);
 116         atomic_inc(&io->write.ctxt->write_ios);
 117
 118         bch2_data_update_read_done(&io->write, io->rbio.pick.crc);
 119 }
 120
 121 struct moving_io *bch2_moving_ctxt_next_pending_write(struct moving_context *ctxt)
 122 {
 123         struct moving_io *io =
 124                 list_first_entry_or_null(&ctxt->reads, struct moving_io, read_list);
 125
 126         return io && io->read_completed ? io : NULL;
 127 }
 128
 129 static void move_read_endio(struct bio *bio)
 130 {
 131         struct moving_io *io = container_of(bio, struct moving_io, rbio.bio);
 132         struct moving_context *ctxt = io->write.ctxt;
 133
 134         atomic_sub(io->read_sectors, &ctxt->read_sectors);
 135         atomic_dec(&ctxt->read_ios);
 136         io->read_completed = true;
 137
 138         wake_up(&ctxt->wait);
 139         closure_put(&ctxt->cl);
 140 }
 141
 142 void bch2_moving_ctxt_do_pending_writes(struct moving_context *ctxt)
 143 {
 144         struct moving_io *io;
 145
 146         while ((io = bch2_moving_ctxt_next_pending_write(ctxt))) {
 147                 bch2_trans_unlock_long(ctxt->trans);
 148                 list_del(&io->read_list);
 149                 move_write(io);
 150         }
 151 }
 152
 153 void bch2_move_ctxt_wait_for_io(struct moving_context *ctxt)
 154 {
 155         unsigned sectors_pending = atomic_read(&ctxt->write_sectors);
 156
 157         move_ctxt_wait_event(ctxt,
 158                 !atomic_read(&ctxt->write_sectors) ||
 159                 atomic_read(&ctxt->write_sectors) != sectors_pending);
 160 }
 161
 162 void bch2_moving_ctxt_flush_all(struct moving_context *ctxt)
 163 {
 164         move_ctxt_wait_event(ctxt, list_empty(&ctxt->reads));
 165         bch2_trans_unlock_long(ctxt->trans);
 166         closure_sync(&ctxt->cl);
 167 }
 168
 169 void bch2_moving_ctxt_exit(struct moving_context *ctxt)
 170 {
 171         struct bch_fs *c = ctxt->trans->c;
 172
 173         bch2_moving_ctxt_flush_all(ctxt);
 174
 175         EBUG_ON(atomic_read(&ctxt->write_sectors));
 176         EBUG_ON(atomic_read(&ctxt->write_ios));
 177         EBUG_ON(atomic_read(&ctxt->read_sectors));
 178         EBUG_ON(atomic_read(&ctxt->read_ios));
 179
 180         mutex_lock(&c->moving_context_lock);
 181         list_del(&ctxt->list);
 182         mutex_unlock(&c->moving_context_lock);
 183
 184         bch2_trans_put(ctxt->trans);
 185         memset(ctxt, 0, sizeof(*ctxt));
 186 }
 187
 188 void bch2_moving_ctxt_init(struct moving_context *ctxt,
 189                            struct bch_fs *c,
 190                            struct bch_ratelimit *rate,
 191                            struct bch_move_stats *stats,
 192                            struct write_point_specifier wp,
 193                            bool wait_on_copygc)
 194 {
 195         memset(ctxt, 0, sizeof(*ctxt));
 196
 197         ctxt->trans     = bch2_trans_get(c);
 198         ctxt->fn        = (void *) _RET_IP_;
 199         ctxt->rate      = rate;
 200         ctxt->stats     = stats;
 201         ctxt->wp        = wp;
 202         ctxt->wait_on_copygc = wait_on_copygc;
 203
 204         closure_init_stack(&ctxt->cl);
 205
 206         mutex_init(&ctxt->lock);
 207         INIT_LIST_HEAD(&ctxt->reads);
 208         INIT_LIST_HEAD(&ctxt->ios);
 209         init_waitqueue_head(&ctxt->wait);
 210
 211         mutex_lock(&c->moving_context_lock);
 212         list_add(&ctxt->list, &c->moving_context_list);
 213         mutex_unlock(&c->moving_context_lock);
 214 }
 215
 216 void bch2_move_stats_exit(struct bch_move_stats *stats, struct bch_fs *c)
 217 {
 218         trace_move_data(c, stats);
 219 }
 220
 221 void bch2_move_stats_init(struct bch_move_stats *stats, const char *name)
 222 {
 223         memset(stats, 0, sizeof(*stats));
 224         stats->data_type = BCH_DATA_user;
 225         scnprintf(stats->name, sizeof(stats->name), "%s", name);
 226 }
 227
 228 int bch2_move_extent(struct moving_context *ctxt,
 229                      struct move_bucket_in_flight *bucket_in_flight,
 230                      struct btree_iter *iter,
 231                      struct bkey_s_c k,
 232                      struct bch_io_opts io_opts,
 233                      struct data_update_opts data_opts)
 234 {
 235         struct btree_trans *trans = ctxt->trans;
 236         struct bch_fs *c = trans->c;
 237         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 238         struct moving_io *io;
 239         const union bch_extent_entry *entry;
 240         struct extent_ptr_decoded p;
 241         unsigned sectors = k.k->size, pages;
 242         int ret = -ENOMEM;
 243
 244         if (ctxt->stats)
 245                 ctxt->stats->pos = BBPOS(iter->btree_id, iter->pos);
 246         trace_move_extent2(c, k);
 247
 248         bch2_data_update_opts_normalize(k, &data_opts);
 249
 250         if (!data_opts.rewrite_ptrs &&
 251             !data_opts.extra_replicas) {
 252                 if (data_opts.kill_ptrs)
 253                         return bch2_extent_drop_ptrs(trans, iter, k, data_opts);
 254                 return 0;
 255         }
 256
 257         /*
 258          * Before memory allocations & taking nocow locks in
 259          * bch2_data_update_init():
 260          */
 261         bch2_trans_unlock(trans);
 262
 263         /* write path might have to decompress data: */
 264         bkey_for_each_ptr_decode(k.k, ptrs, p, entry)
 265                 sectors = max_t(unsigned, sectors, p.crc.uncompressed_size);
 266
 267         pages = DIV_ROUND_UP(sectors, PAGE_SECTORS);
 268         io = kzalloc(sizeof(struct moving_io) +
 269                      sizeof(struct bio_vec) * pages, GFP_KERNEL);
 270         if (!io)
 271                 goto err;
 272
 273         INIT_LIST_HEAD(&io->io_list);
 274         io->write.ctxt          = ctxt;
 275         io->read_sectors        = k.k->size;
 276         io->write_sectors       = k.k->size;
 277
 278         bio_init(&io->write.op.wbio.bio, NULL, io->bi_inline_vecs, pages, 0);
 279         bio_set_prio(&io->write.op.wbio.bio,
 280                      IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0));
 281
 282         if (bch2_bio_alloc_pages(&io->write.op.wbio.bio, sectors << 9,
 283                                  GFP_KERNEL))
 284                 goto err_free;
 285
 286         io->rbio.c              = c;
 287         io->rbio.opts           = io_opts;
 288         bio_init(&io->rbio.bio, NULL, io->bi_inline_vecs, pages, 0);
 289         io->rbio.bio.bi_vcnt = pages;
 290         bio_set_prio(&io->rbio.bio, IOPRIO_PRIO_VALUE(IOPRIO_CLASS_IDLE, 0));
 291         io->rbio.bio.bi_iter.bi_size = sectors << 9;
 292
 293         io->rbio.bio.bi_opf             = REQ_OP_READ;
 294         io->rbio.bio.bi_iter.bi_sector  = bkey_start_offset(k.k);
 295         io->rbio.bio.bi_end_io          = move_read_endio;
 296
 297         ret = bch2_data_update_init(trans, iter, ctxt, &io->write, ctxt->wp,
 298                                     io_opts, data_opts, iter->btree_id, k);
 299         if (ret)
 300                 goto err_free_pages;
 301
 302         io->write.op.end_io = move_write_done;
 303
 304         if (ctxt->rate)
 305                 bch2_ratelimit_increment(ctxt->rate, k.k->size);
 306
 307         if (ctxt->stats) {
 308                 atomic64_inc(&ctxt->stats->keys_moved);
 309                 atomic64_add(k.k->size, &ctxt->stats->sectors_moved);
 310         }
 311
 312         if (bucket_in_flight) {
 313                 io->b = bucket_in_flight;
 314                 atomic_inc(&io->b->count);
 315         }
 316
 317         this_cpu_add(c->counters[BCH_COUNTER_io_move], k.k->size);
 318         this_cpu_add(c->counters[BCH_COUNTER_move_extent_read], k.k->size);
 319         trace_move_extent_read2(c, k);
 320
 321         mutex_lock(&ctxt->lock);
 322         atomic_add(io->read_sectors, &ctxt->read_sectors);
 323         atomic_inc(&ctxt->read_ios);
 324
 325         list_add_tail(&io->read_list, &ctxt->reads);
 326         list_add_tail(&io->io_list, &ctxt->ios);
 327         mutex_unlock(&ctxt->lock);
 328
 329         /*
 330          * dropped by move_read_endio() - guards against use after free of
 331          * ctxt when doing wakeup
 332          */
 333         closure_get(&ctxt->cl);
 334         bch2_read_extent(trans, &io->rbio,
 335                          bkey_start_pos(k.k),
 336                          iter->btree_id, k, 0,
 337                          BCH_READ_NODECODE|
 338                          BCH_READ_LAST_FRAGMENT);
 339         return 0;
 340 err_free_pages:
 341         bio_free_pages(&io->write.op.wbio.bio);
 342 err_free:
 343         kfree(io);
 344 err:
 345         if (ret == -BCH_ERR_data_update_done)
 346                 return 0;
 347
 348         if (bch2_err_matches(ret, EROFS) ||
 349             bch2_err_matches(ret, BCH_ERR_transaction_restart))
 350                 return ret;
 351
 352         count_event(c, move_extent_start_fail);
 353
 354         if (trace_move_extent_start_fail_enabled()) {
 355                 struct printbuf buf = PRINTBUF;
 356
 357                 bch2_bkey_val_to_text(&buf, c, k);
 358                 prt_str(&buf, ": ");
 359                 prt_str(&buf, bch2_err_str(ret));
 360                 trace_move_extent_start_fail(c, buf.buf);
 361                 printbuf_exit(&buf);
 362         }
 363         return ret;
 364 }
 365
 366 struct bch_io_opts *bch2_move_get_io_opts(struct btree_trans *trans,
 367                           struct per_snapshot_io_opts *io_opts,
 368                           struct bkey_s_c extent_k)
 369 {
 370         struct bch_fs *c = trans->c;
 371         u32 restart_count = trans->restart_count;
 372         int ret = 0;
 373
 374         if (io_opts->cur_inum != extent_k.k->p.inode) {
 375                 io_opts->d.nr = 0;
 376
 377                 ret = for_each_btree_key(trans, iter, BTREE_ID_inodes, POS(0, extent_k.k->p.inode),
 378                                          BTREE_ITER_ALL_SNAPSHOTS, k, ({
 379                         if (k.k->p.offset != extent_k.k->p.inode)
 380                                 break;
 381
 382                         if (!bkey_is_inode(k.k))
 383                                 continue;
 384
 385                         struct bch_inode_unpacked inode;
 386                         BUG_ON(bch2_inode_unpack(k, &inode));
 387
 388                         struct snapshot_io_opts_entry e = { .snapshot = k.k->p.snapshot };
 389                         bch2_inode_opts_get(&e.io_opts, trans->c, &inode);
 390
 391                         darray_push(&io_opts->d, e);
 392                 }));
 393                 io_opts->cur_inum = extent_k.k->p.inode;
 394         }
 395
 396         ret = ret ?: trans_was_restarted(trans, restart_count);
 397         if (ret)
 398                 return ERR_PTR(ret);
 399
 400         if (extent_k.k->p.snapshot)
 401                 darray_for_each(io_opts->d, i)
 402                         if (bch2_snapshot_is_ancestor(c, extent_k.k->p.snapshot, i->snapshot))
 403                                 return &i->io_opts;
 404
 405         return &io_opts->fs_io_opts;
 406 }
 407
 408 int bch2_move_get_io_opts_one(struct btree_trans *trans,
 409                               struct bch_io_opts *io_opts,
 410                               struct bkey_s_c extent_k)
 411 {
 412         struct btree_iter iter;
 413         struct bkey_s_c k;
 414         int ret;
 415
 416         /* reflink btree? */
 417         if (!extent_k.k->p.inode) {
 418                 *io_opts = bch2_opts_to_inode_opts(trans->c->opts);
 419                 return 0;
 420         }
 421
 422         k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_inodes,
 423                                SPOS(0, extent_k.k->p.inode, extent_k.k->p.snapshot),
 424                                BTREE_ITER_CACHED);
 425         ret = bkey_err(k);
 426         if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 427                 return ret;
 428
 429         if (!ret && bkey_is_inode(k.k)) {
 430                 struct bch_inode_unpacked inode;
 431                 bch2_inode_unpack(k, &inode);
 432                 bch2_inode_opts_get(io_opts, trans->c, &inode);
 433         } else {
 434                 *io_opts = bch2_opts_to_inode_opts(trans->c->opts);
 435         }
 436
 437         bch2_trans_iter_exit(trans, &iter);
 438         return 0;
 439 }
 440
 441 int bch2_move_ratelimit(struct moving_context *ctxt)
 442 {
 443         struct bch_fs *c = ctxt->trans->c;
 444         bool is_kthread = current->flags & PF_KTHREAD;
 445         u64 delay;
 446
 447         if (ctxt->wait_on_copygc && c->copygc_running) {
 448                 bch2_moving_ctxt_flush_all(ctxt);
 449                 wait_event_killable(c->copygc_running_wq,
 450                                     !c->copygc_running ||
 451                                     (is_kthread && kthread_should_stop()));
 452         }
 453
 454         do {
 455                 delay = ctxt->rate ? bch2_ratelimit_delay(ctxt->rate) : 0;
 456
 457                 if (is_kthread && kthread_should_stop())
 458                         return 1;
 459
 460                 if (delay)
 461                         move_ctxt_wait_event_timeout(ctxt,
 462                                         freezing(current) ||
 463                                         (is_kthread && kthread_should_stop()),
 464                                         delay);
 465
 466                 if (unlikely(freezing(current))) {
 467                         bch2_moving_ctxt_flush_all(ctxt);
 468                         try_to_freeze();
 469                 }
 470         } while (delay);
 471
 472         /*
 473          * XXX: these limits really ought to be per device, SSDs and hard drives
 474          * will want different limits
 475          */
 476         move_ctxt_wait_event(ctxt,
 477                 atomic_read(&ctxt->write_sectors) < c->opts.move_bytes_in_flight >> 9 &&
 478                 atomic_read(&ctxt->read_sectors) < c->opts.move_bytes_in_flight >> 9 &&
 479                 atomic_read(&ctxt->write_ios) < c->opts.move_ios_in_flight &&
 480                 atomic_read(&ctxt->read_ios) < c->opts.move_ios_in_flight);
 481
 482         return 0;
 483 }
 484
 485 static int bch2_move_data_btree(struct moving_context *ctxt,
 486                                 struct bpos start,
 487                                 struct bpos end,
 488                                 move_pred_fn pred, void *arg,
 489                                 enum btree_id btree_id)
 490 {
 491         struct btree_trans *trans = ctxt->trans;
 492         struct bch_fs *c = trans->c;
 493         struct per_snapshot_io_opts snapshot_io_opts;
 494         struct bch_io_opts *io_opts;
 495         struct bkey_buf sk;
 496         struct btree_iter iter;
 497         struct bkey_s_c k;
 498         struct data_update_opts data_opts;
 499         int ret = 0, ret2;
 500
 501         per_snapshot_io_opts_init(&snapshot_io_opts, c);
 502         bch2_bkey_buf_init(&sk);
 503
 504         if (ctxt->stats) {
 505                 ctxt->stats->data_type  = BCH_DATA_user;
 506                 ctxt->stats->pos        = BBPOS(btree_id, start);
 507         }
 508
 509         bch2_trans_iter_init(trans, &iter, btree_id, start,
 510                              BTREE_ITER_PREFETCH|
 511                              BTREE_ITER_ALL_SNAPSHOTS);
 512
 513         if (ctxt->rate)
 514                 bch2_ratelimit_reset(ctxt->rate);
 515
 516         while (!bch2_move_ratelimit(ctxt)) {
 517                 bch2_trans_begin(trans);
 518
 519                 k = bch2_btree_iter_peek(&iter);
 520                 if (!k.k)
 521                         break;
 522
 523                 ret = bkey_err(k);
 524                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 525                         continue;
 526                 if (ret)
 527                         break;
 528
 529                 if (bkey_ge(bkey_start_pos(k.k), end))
 530                         break;
 531
 532                 if (ctxt->stats)
 533                         ctxt->stats->pos = BBPOS(iter.btree_id, iter.pos);
 534
 535                 if (!bkey_extent_is_direct_data(k.k))
 536                         goto next_nondata;
 537
 538                 io_opts = bch2_move_get_io_opts(trans, &snapshot_io_opts, k);
 539                 ret = PTR_ERR_OR_ZERO(io_opts);
 540                 if (ret)
 541                         continue;
 542
 543                 memset(&data_opts, 0, sizeof(data_opts));
 544                 if (!pred(c, arg, k, io_opts, &data_opts))
 545                         goto next;
 546
 547                 /*
 548                  * The iterator gets unlocked by __bch2_read_extent - need to
 549                  * save a copy of @k elsewhere:
 550                  */
 551                 bch2_bkey_buf_reassemble(&sk, c, k);
 552                 k = bkey_i_to_s_c(sk.k);
 553
 554                 ret2 = bch2_move_extent(ctxt, NULL, &iter, k, *io_opts, data_opts);
 555                 if (ret2) {
 556                         if (bch2_err_matches(ret2, BCH_ERR_transaction_restart))
 557                                 continue;
 558
 559                         if (ret2 == -ENOMEM) {
 560                                 /* memory allocation failure, wait for some IO to finish */
 561                                 bch2_move_ctxt_wait_for_io(ctxt);
 562                                 continue;
 563                         }
 564
 565                         /* XXX signal failure */
 566                         goto next;
 567                 }
 568 next:
 569                 if (ctxt->stats)
 570                         atomic64_add(k.k->size, &ctxt->stats->sectors_seen);
 571 next_nondata:
 572                 bch2_btree_iter_advance(&iter);
 573         }
 574
 575         bch2_trans_iter_exit(trans, &iter);
 576         bch2_bkey_buf_exit(&sk, c);
 577         per_snapshot_io_opts_exit(&snapshot_io_opts);
 578
 579         return ret;
 580 }
 581
 582 int __bch2_move_data(struct moving_context *ctxt,
 583                      struct bbpos start,
 584                      struct bbpos end,
 585                      move_pred_fn pred, void *arg)
 586 {
 587         struct bch_fs *c = ctxt->trans->c;
 588         enum btree_id id;
 589         int ret = 0;
 590
 591         for (id = start.btree;
 592              id <= min_t(unsigned, end.btree, btree_id_nr_alive(c) - 1);
 593              id++) {
 594                 ctxt->stats->pos = BBPOS(id, POS_MIN);
 595
 596                 if (!btree_type_has_ptrs(id) ||
 597                     !bch2_btree_id_root(c, id)->b)
 598                         continue;
 599
 600                 ret = bch2_move_data_btree(ctxt,
 601                                        id == start.btree ? start.pos : POS_MIN,
 602                                        id == end.btree   ? end.pos   : POS_MAX,
 603                                        pred, arg, id);
 604                 if (ret)
 605                         break;
 606         }
 607
 608         return ret;
 609 }
 610
 611 int bch2_move_data(struct bch_fs *c,
 612                    struct bbpos start,
 613                    struct bbpos end,
 614                    struct bch_ratelimit *rate,
 615                    struct bch_move_stats *stats,
 616                    struct write_point_specifier wp,
 617                    bool wait_on_copygc,
 618                    move_pred_fn pred, void *arg)
 619 {
 620
 621         struct moving_context ctxt;
 622         int ret;
 623
 624         bch2_moving_ctxt_init(&ctxt, c, rate, stats, wp, wait_on_copygc);
 625         ret = __bch2_move_data(&ctxt, start, end, pred, arg);
 626         bch2_moving_ctxt_exit(&ctxt);
 627
 628         return ret;
 629 }
 630
 631 int bch2_evacuate_bucket(struct moving_context *ctxt,
 632                            struct move_bucket_in_flight *bucket_in_flight,
 633                            struct bpos bucket, int gen,
 634                            struct data_update_opts _data_opts)
 635 {
 636         struct btree_trans *trans = ctxt->trans;
 637         struct bch_fs *c = trans->c;
 638         bool is_kthread = current->flags & PF_KTHREAD;
 639         struct bch_io_opts io_opts = bch2_opts_to_inode_opts(c->opts);
 640         struct btree_iter iter;
 641         struct bkey_buf sk;
 642         struct bch_backpointer bp;
 643         struct bch_alloc_v4 a_convert;
 644         const struct bch_alloc_v4 *a;
 645         struct bkey_s_c k;
 646         struct data_update_opts data_opts;
 647         unsigned dirty_sectors, bucket_size;
 648         u64 fragmentation;
 649         struct bpos bp_pos = POS_MIN;
 650         int ret = 0;
 651
 652         trace_bucket_evacuate(c, &bucket);
 653
 654         bch2_bkey_buf_init(&sk);
 655
 656         /*
 657          * We're not run in a context that handles transaction restarts:
 658          */
 659         bch2_trans_begin(trans);
 660
 661         bch2_trans_iter_init(trans, &iter, BTREE_ID_alloc,
 662                              bucket, BTREE_ITER_CACHED);
 663         ret = lockrestart_do(trans,
 664                         bkey_err(k = bch2_btree_iter_peek_slot(&iter)));
 665         bch2_trans_iter_exit(trans, &iter);
 666
 667         bch_err_msg(c, ret, "looking up alloc key");
 668         if (ret)
 669                 goto err;
 670
 671         a = bch2_alloc_to_v4(k, &a_convert);
 672         dirty_sectors = bch2_bucket_sectors_dirty(*a);
 673         bucket_size = bch_dev_bkey_exists(c, bucket.inode)->mi.bucket_size;
 674         fragmentation = a->fragmentation_lru;
 675
 676         ret = bch2_btree_write_buffer_tryflush(trans);
 677         bch_err_msg(c, ret, "flushing btree write buffer");
 678         if (ret)
 679                 goto err;
 680
 681         while (!(ret = bch2_move_ratelimit(ctxt))) {
 682                 if (is_kthread && kthread_should_stop())
 683                         break;
 684
 685                 bch2_trans_begin(trans);
 686
 687                 ret = bch2_get_next_backpointer(trans, bucket, gen,
 688                                                 &bp_pos, &bp,
 689                                                 BTREE_ITER_CACHED);
 690                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 691                         continue;
 692                 if (ret)
 693                         goto err;
 694                 if (bkey_eq(bp_pos, POS_MAX))
 695                         break;
 696
 697                 if (!bp.level) {
 698                         k = bch2_backpointer_get_key(trans, &iter, bp_pos, bp, 0);
 699                         ret = bkey_err(k);
 700                         if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 701                                 continue;
 702                         if (ret)
 703                                 goto err;
 704                         if (!k.k)
 705                                 goto next;
 706
 707                         bch2_bkey_buf_reassemble(&sk, c, k);
 708                         k = bkey_i_to_s_c(sk.k);
 709
 710                         ret = bch2_move_get_io_opts_one(trans, &io_opts, k);
 711                         if (ret) {
 712                                 bch2_trans_iter_exit(trans, &iter);
 713                                 continue;
 714                         }
 715
 716                         data_opts = _data_opts;
 717                         data_opts.target        = io_opts.background_target;
 718                         data_opts.rewrite_ptrs = 0;
 719
 720                         unsigned i = 0;
 721                         bkey_for_each_ptr(bch2_bkey_ptrs_c(k), ptr) {
 722                                 if (ptr->dev == bucket.inode) {
 723                                         data_opts.rewrite_ptrs |= 1U << i;
 724                                         if (ptr->cached) {
 725                                                 bch2_trans_iter_exit(trans, &iter);
 726                                                 goto next;
 727                                         }
 728                                 }
 729                                 i++;
 730                         }
 731
 732                         ret = bch2_move_extent(ctxt, bucket_in_flight,
 733                                                &iter, k, io_opts, data_opts);
 734                         bch2_trans_iter_exit(trans, &iter);
 735
 736                         if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 737                                 continue;
 738                         if (ret == -ENOMEM) {
 739                                 /* memory allocation failure, wait for some IO to finish */
 740                                 bch2_move_ctxt_wait_for_io(ctxt);
 741                                 continue;
 742                         }
 743                         if (ret)
 744                                 goto err;
 745
 746                         if (ctxt->stats)
 747                                 atomic64_add(k.k->size, &ctxt->stats->sectors_seen);
 748                 } else {
 749                         struct btree *b;
 750
 751                         b = bch2_backpointer_get_node(trans, &iter, bp_pos, bp);
 752                         ret = PTR_ERR_OR_ZERO(b);
 753                         if (ret == -BCH_ERR_backpointer_to_overwritten_btree_node)
 754                                 continue;
 755                         if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 756                                 continue;
 757                         if (ret)
 758                                 goto err;
 759                         if (!b)
 760                                 goto next;
 761
 762                         ret = bch2_btree_node_rewrite(trans, &iter, b, 0);
 763                         bch2_trans_iter_exit(trans, &iter);
 764
 765                         if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 766                                 continue;
 767                         if (ret)
 768                                 goto err;
 769
 770                         if (ctxt->rate)
 771                                 bch2_ratelimit_increment(ctxt->rate,
 772                                                          c->opts.btree_node_size >> 9);
 773                         if (ctxt->stats) {
 774                                 atomic64_add(c->opts.btree_node_size >> 9, &ctxt->stats->sectors_seen);
 775                                 atomic64_add(c->opts.btree_node_size >> 9, &ctxt->stats->sectors_moved);
 776                         }
 777                 }
 778 next:
 779                 bp_pos = bpos_nosnap_successor(bp_pos);
 780         }
 781
 782         trace_evacuate_bucket(c, &bucket, dirty_sectors, bucket_size, fragmentation, ret);
 783 err:
 784         bch2_bkey_buf_exit(&sk, c);
 785         return ret;
 786 }
 787
 788 typedef bool (*move_btree_pred)(struct bch_fs *, void *,
 789                                 struct btree *, struct bch_io_opts *,
 790                                 struct data_update_opts *);
 791
 792 static int bch2_move_btree(struct bch_fs *c,
 793                            struct bbpos start,
 794                            struct bbpos end,
 795                            move_btree_pred pred, void *arg,
 796                            struct bch_move_stats *stats)
 797 {
 798         bool kthread = (current->flags & PF_KTHREAD) != 0;
 799         struct bch_io_opts io_opts = bch2_opts_to_inode_opts(c->opts);
 800         struct moving_context ctxt;
 801         struct btree_trans *trans;
 802         struct btree_iter iter;
 803         struct btree *b;
 804         enum btree_id btree;
 805         struct data_update_opts data_opts;
 806         int ret = 0;
 807
 808         bch2_moving_ctxt_init(&ctxt, c, NULL, stats,
 809                               writepoint_ptr(&c->btree_write_point),
 810                               true);
 811         trans = ctxt.trans;
 812
 813         stats->data_type = BCH_DATA_btree;
 814
 815         for (btree = start.btree;
 816              btree <= min_t(unsigned, end.btree, btree_id_nr_alive(c) - 1);
 817              btree ++) {
 818                 stats->pos = BBPOS(btree, POS_MIN);
 819
 820                 if (!bch2_btree_id_root(c, btree)->b)
 821                         continue;
 822
 823                 bch2_trans_node_iter_init(trans, &iter, btree, POS_MIN, 0, 0,
 824                                           BTREE_ITER_PREFETCH);
 825 retry:
 826                 ret = 0;
 827                 while (bch2_trans_begin(trans),
 828                        (b = bch2_btree_iter_peek_node(&iter)) &&
 829                        !(ret = PTR_ERR_OR_ZERO(b))) {
 830                         if (kthread && kthread_should_stop())
 831                                 break;
 832
 833                         if ((cmp_int(btree, end.btree) ?:
 834                              bpos_cmp(b->key.k.p, end.pos)) > 0)
 835                                 break;
 836
 837                         stats->pos = BBPOS(iter.btree_id, iter.pos);
 838
 839                         if (!pred(c, arg, b, &io_opts, &data_opts))
 840                                 goto next;
 841
 842                         ret = bch2_btree_node_rewrite(trans, &iter, b, 0) ?: ret;
 843                         if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 844                                 continue;
 845                         if (ret)
 846                                 break;
 847 next:
 848                         bch2_btree_iter_next_node(&iter);
 849                 }
 850                 if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 851                         goto retry;
 852
 853                 bch2_trans_iter_exit(trans, &iter);
 854
 855                 if (kthread && kthread_should_stop())
 856                         break;
 857         }
 858
 859         bch_err_fn(c, ret);
 860         bch2_moving_ctxt_exit(&ctxt);
 861         bch2_btree_interior_updates_flush(c);
 862
 863         return ret;
 864 }
 865
 866 static bool rereplicate_pred(struct bch_fs *c, void *arg,
 867                              struct bkey_s_c k,
 868                              struct bch_io_opts *io_opts,
 869                              struct data_update_opts *data_opts)
 870 {
 871         unsigned nr_good = bch2_bkey_durability(c, k);
 872         unsigned replicas = bkey_is_btree_ptr(k.k)
 873                 ? c->opts.metadata_replicas
 874                 : io_opts->data_replicas;
 875
 876         if (!nr_good || nr_good >= replicas)
 877                 return false;
 878
 879         data_opts->target               = 0;
 880         data_opts->extra_replicas       = replicas - nr_good;
 881         data_opts->btree_insert_flags   = 0;
 882         return true;
 883 }
 884
 885 static bool migrate_pred(struct bch_fs *c, void *arg,
 886                          struct bkey_s_c k,
 887                          struct bch_io_opts *io_opts,
 888                          struct data_update_opts *data_opts)
 889 {
 890         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
 891         struct bch_ioctl_data *op = arg;
 892         unsigned i = 0;
 893
 894         data_opts->rewrite_ptrs         = 0;
 895         data_opts->target               = 0;
 896         data_opts->extra_replicas       = 0;
 897         data_opts->btree_insert_flags   = 0;
 898
 899         bkey_for_each_ptr(ptrs, ptr) {
 900                 if (ptr->dev == op->migrate.dev)
 901                         data_opts->rewrite_ptrs |= 1U << i;
 902                 i++;
 903         }
 904
 905         return data_opts->rewrite_ptrs != 0;
 906 }
 907
 908 static bool rereplicate_btree_pred(struct bch_fs *c, void *arg,
 909                                    struct btree *b,
 910                                    struct bch_io_opts *io_opts,
 911                                    struct data_update_opts *data_opts)
 912 {
 913         return rereplicate_pred(c, arg, bkey_i_to_s_c(&b->key), io_opts, data_opts);
 914 }
 915
 916 static bool migrate_btree_pred(struct bch_fs *c, void *arg,
 917                                struct btree *b,
 918                                struct bch_io_opts *io_opts,
 919                                struct data_update_opts *data_opts)
 920 {
 921         return migrate_pred(c, arg, bkey_i_to_s_c(&b->key), io_opts, data_opts);
 922 }
 923
 924 static bool bformat_needs_redo(struct bkey_format *f)
 925 {
 926         unsigned i;
 927
 928         for (i = 0; i < f->nr_fields; i++) {
 929                 unsigned unpacked_bits = bch2_bkey_format_current.bits_per_field[i];
 930                 u64 unpacked_mask = ~((~0ULL << 1) << (unpacked_bits - 1));
 931                 u64 field_offset = le64_to_cpu(f->field_offset[i]);
 932
 933                 if (f->bits_per_field[i] > unpacked_bits)
 934                         return true;
 935
 936                 if ((f->bits_per_field[i] == unpacked_bits) && field_offset)
 937                         return true;
 938
 939                 if (((field_offset + ((1ULL << f->bits_per_field[i]) - 1)) &
 940                      unpacked_mask) <
 941                     field_offset)
 942                         return true;
 943         }
 944
 945         return false;
 946 }
 947
 948 static bool rewrite_old_nodes_pred(struct bch_fs *c, void *arg,
 949                                    struct btree *b,
 950                                    struct bch_io_opts *io_opts,
 951                                    struct data_update_opts *data_opts)
 952 {
 953         if (b->version_ondisk != c->sb.version ||
 954             btree_node_need_rewrite(b) ||
 955             bformat_needs_redo(&b->format)) {
 956                 data_opts->target               = 0;
 957                 data_opts->extra_replicas       = 0;
 958                 data_opts->btree_insert_flags   = 0;
 959                 return true;
 960         }
 961
 962         return false;
 963 }
 964
 965 int bch2_scan_old_btree_nodes(struct bch_fs *c, struct bch_move_stats *stats)
 966 {
 967         int ret;
 968
 969         ret = bch2_move_btree(c,
 970                               BBPOS_MIN,
 971                               BBPOS_MAX,
 972                               rewrite_old_nodes_pred, c, stats);
 973         if (!ret) {
 974                 mutex_lock(&c->sb_lock);
 975                 c->disk_sb.sb->compat[0] |= cpu_to_le64(1ULL << BCH_COMPAT_extents_above_btree_updates_done);
 976                 c->disk_sb.sb->compat[0] |= cpu_to_le64(1ULL << BCH_COMPAT_bformat_overflow_done);
 977                 c->disk_sb.sb->version_min = c->disk_sb.sb->version;
 978                 bch2_write_super(c);
 979                 mutex_unlock(&c->sb_lock);
 980         }
 981
 982         bch_err_fn(c, ret);
 983         return ret;
 984 }
 985
 986 static bool drop_extra_replicas_pred(struct bch_fs *c, void *arg,
 987                              struct bkey_s_c k,
 988                              struct bch_io_opts *io_opts,
 989                              struct data_update_opts *data_opts)
 990 {
 991         unsigned durability = bch2_bkey_durability(c, k);
 992         unsigned replicas = bkey_is_btree_ptr(k.k)
 993                 ? c->opts.metadata_replicas
 994                 : io_opts->data_replicas;
 995         const union bch_extent_entry *entry;
 996         struct extent_ptr_decoded p;
 997         unsigned i = 0;
 998
 999         bkey_for_each_ptr_decode(k.k, bch2_bkey_ptrs_c(k), p, entry) {
1000                 unsigned d = bch2_extent_ptr_durability(c, &p);
1001
1002                 if (d && durability - d >= replicas) {
1003                         data_opts->kill_ptrs |= BIT(i);
1004                         durability -= d;
1005                 }
1006
1007                 i++;
1008         }
1009
1010         return data_opts->kill_ptrs != 0;
1011 }
1012
1013 static bool drop_extra_replicas_btree_pred(struct bch_fs *c, void *arg,
1014                                    struct btree *b,
1015                                    struct bch_io_opts *io_opts,
1016                                    struct data_update_opts *data_opts)
1017 {
1018         return drop_extra_replicas_pred(c, arg, bkey_i_to_s_c(&b->key), io_opts, data_opts);
1019 }
1020
1021 int bch2_data_job(struct bch_fs *c,
1022                   struct bch_move_stats *stats,
1023                   struct bch_ioctl_data op)
1024 {
1025         struct bbpos start      = BBPOS(op.start_btree, op.start_pos);
1026         struct bbpos end        = BBPOS(op.end_btree, op.end_pos);
1027         int ret = 0;
1028
1029         if (op.op >= BCH_DATA_OP_NR)
1030                 return -EINVAL;
1031
1032         bch2_move_stats_init(stats, bch2_data_ops_strs[op.op]);
1033
1034         switch (op.op) {
1035         case BCH_DATA_OP_rereplicate:
1036                 stats->data_type = BCH_DATA_journal;
1037                 ret = bch2_journal_flush_device_pins(&c->journal, -1);
1038                 ret = bch2_move_btree(c, start, end,
1039                                       rereplicate_btree_pred, c, stats) ?: ret;
1040                 ret = bch2_move_data(c, start, end,
1041                                      NULL,
1042                                      stats,
1043                                      writepoint_hashed((unsigned long) current),
1044                                      true,
1045                                      rereplicate_pred, c) ?: ret;
1046                 ret = bch2_replicas_gc2(c) ?: ret;
1047                 break;
1048         case BCH_DATA_OP_migrate:
1049                 if (op.migrate.dev >= c->sb.nr_devices)
1050                         return -EINVAL;
1051
1052                 stats->data_type = BCH_DATA_journal;
1053                 ret = bch2_journal_flush_device_pins(&c->journal, op.migrate.dev);
1054                 ret = bch2_move_btree(c, start, end,
1055                                       migrate_btree_pred, &op, stats) ?: ret;
1056                 ret = bch2_move_data(c, start, end,
1057                                      NULL,
1058                                      stats,
1059                                      writepoint_hashed((unsigned long) current),
1060                                      true,
1061                                      migrate_pred, &op) ?: ret;
1062                 ret = bch2_replicas_gc2(c) ?: ret;
1063                 break;
1064         case BCH_DATA_OP_rewrite_old_nodes:
1065                 ret = bch2_scan_old_btree_nodes(c, stats);
1066                 break;
1067         case BCH_DATA_OP_drop_extra_replicas:
1068                 ret = bch2_move_btree(c, start, end,
1069                                 drop_extra_replicas_btree_pred, c, stats) ?: ret;
1070                 ret = bch2_move_data(c, start, end, NULL, stats,
1071                                 writepoint_hashed((unsigned long) current),
1072                                 true,
1073                                 drop_extra_replicas_pred, c) ?: ret;
1074                 ret = bch2_replicas_gc2(c) ?: ret;
1075                 break;
1076         default:
1077                 ret = -EINVAL;
1078         }
1079
1080         bch2_move_stats_exit(stats, c);
1081         return ret;
1082 }
1083
1084 void bch2_move_stats_to_text(struct printbuf *out, struct bch_move_stats *stats)
1085 {
1086         prt_printf(out, "%s: data type=%s pos=",
1087                    stats->name,
1088                    bch2_data_types[stats->data_type]);
1089         bch2_bbpos_to_text(out, stats->pos);
1090         prt_newline(out);
1091         printbuf_indent_add(out, 2);
1092
1093         prt_str(out, "keys moved:  ");
1094         prt_u64(out, atomic64_read(&stats->keys_moved));
1095         prt_newline(out);
1096
1097         prt_str(out, "keys raced:  ");
1098         prt_u64(out, atomic64_read(&stats->keys_raced));
1099         prt_newline(out);
1100
1101         prt_str(out, "bytes seen:  ");
1102         prt_human_readable_u64(out, atomic64_read(&stats->sectors_seen) << 9);
1103         prt_newline(out);
1104
1105         prt_str(out, "bytes moved: ");
1106         prt_human_readable_u64(out, atomic64_read(&stats->sectors_moved) << 9);
1107         prt_newline(out);
1108
1109         prt_str(out, "bytes raced: ");
1110         prt_human_readable_u64(out, atomic64_read(&stats->sectors_raced) << 9);
1111         prt_newline(out);
1112
1113         printbuf_indent_sub(out, 2);
1114 }
1115
1116 static void bch2_moving_ctxt_to_text(struct printbuf *out, struct bch_fs *c, struct moving_context *ctxt)
1117 {
1118         struct moving_io *io;
1119
1120         bch2_move_stats_to_text(out, ctxt->stats);
1121         printbuf_indent_add(out, 2);
1122
1123         prt_printf(out, "reads: ios %u/%u sectors %u/%u",
1124                    atomic_read(&ctxt->read_ios),
1125                    c->opts.move_ios_in_flight,
1126                    atomic_read(&ctxt->read_sectors),
1127                    c->opts.move_bytes_in_flight >> 9);
1128         prt_newline(out);
1129
1130         prt_printf(out, "writes: ios %u/%u sectors %u/%u",
1131                    atomic_read(&ctxt->write_ios),
1132                    c->opts.move_ios_in_flight,
1133                    atomic_read(&ctxt->write_sectors),
1134                    c->opts.move_bytes_in_flight >> 9);
1135         prt_newline(out);
1136
1137         printbuf_indent_add(out, 2);
1138
1139         mutex_lock(&ctxt->lock);
1140         list_for_each_entry(io, &ctxt->ios, io_list)
1141                 bch2_write_op_to_text(out, &io->write.op);
1142         mutex_unlock(&ctxt->lock);
1143
1144         printbuf_indent_sub(out, 4);
1145 }
1146
1147 void bch2_fs_moving_ctxts_to_text(struct printbuf *out, struct bch_fs *c)
1148 {
1149         struct moving_context *ctxt;
1150
1151         mutex_lock(&c->moving_context_lock);
1152         list_for_each_entry(ctxt, &c->moving_context_list, list)
1153                 bch2_moving_ctxt_to_text(out, c, ctxt);
1154         mutex_unlock(&c->moving_context_lock);
1155 }
1156
1157 void bch2_fs_move_init(struct bch_fs *c)
1158 {
1159         INIT_LIST_HEAD(&c->moving_context_list);
1160         mutex_init(&c->moving_context_lock);
1161 }