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

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 /* erasure coding */
   4
   5 #include "bcachefs.h"
   6 #include "alloc_foreground.h"
   7 #include "bkey_on_stack.h"
   8 #include "bset.h"
   9 #include "btree_gc.h"
  10 #include "btree_update.h"
  11 #include "buckets.h"
  12 #include "disk_groups.h"
  13 #include "ec.h"
  14 #include "error.h"
  15 #include "io.h"
  16 #include "keylist.h"
  17 #include "recovery.h"
  18 #include "super-io.h"
  19 #include "util.h"
  20
  21 #include <linux/sort.h>
  22
  23 #ifdef __KERNEL__
  24
  25 #include <linux/raid/pq.h>
  26 #include <linux/raid/xor.h>
  27
  28 static void raid5_recov(unsigned disks, unsigned failed_idx,
  29                         size_t size, void **data)
  30 {
  31         unsigned i = 2, nr;
  32
  33         BUG_ON(failed_idx >= disks);
  34
  35         swap(data[0], data[failed_idx]);
  36         memcpy(data[0], data[1], size);
  37
  38         while (i < disks) {
  39                 nr = min_t(unsigned, disks - i, MAX_XOR_BLOCKS);
  40                 xor_blocks(nr, size, data[0], data + i);
  41                 i += nr;
  42         }
  43
  44         swap(data[0], data[failed_idx]);
  45 }
  46
  47 static void raid_gen(int nd, int np, size_t size, void **v)
  48 {
  49         if (np >= 1)
  50                 raid5_recov(nd + np, nd, size, v);
  51         if (np >= 2)
  52                 raid6_call.gen_syndrome(nd + np, size, v);
  53         BUG_ON(np > 2);
  54 }
  55
  56 static void raid_rec(int nr, int *ir, int nd, int np, size_t size, void **v)
  57 {
  58         switch (nr) {
  59         case 0:
  60                 break;
  61         case 1:
  62                 if (ir[0] < nd + 1)
  63                         raid5_recov(nd + 1, ir[0], size, v);
  64                 else
  65                         raid6_call.gen_syndrome(nd + np, size, v);
  66                 break;
  67         case 2:
  68                 if (ir[1] < nd) {
  69                         /* data+data failure. */
  70                         raid6_2data_recov(nd + np, size, ir[0], ir[1], v);
  71                 } else if (ir[0] < nd) {
  72                         /* data + p/q failure */
  73
  74                         if (ir[1] == nd) /* data + p failure */
  75                                 raid6_datap_recov(nd + np, size, ir[0], v);
  76                         else { /* data + q failure */
  77                                 raid5_recov(nd + 1, ir[0], size, v);
  78                                 raid6_call.gen_syndrome(nd + np, size, v);
  79                         }
  80                 } else {
  81                         raid_gen(nd, np, size, v);
  82                 }
  83                 break;
  84         default:
  85                 BUG();
  86         }
  87 }
  88
  89 #else
  90
  91 #include <raid/raid.h>
  92
  93 #endif
  94
  95 struct ec_bio {
  96         struct bch_dev          *ca;
  97         struct ec_stripe_buf    *buf;
  98         size_t                  idx;
  99         struct bio              bio;
 100 };
 101
 102 /* Stripes btree keys: */
 103
 104 const char *bch2_stripe_invalid(const struct bch_fs *c, struct bkey_s_c k)
 105 {
 106         const struct bch_stripe *s = bkey_s_c_to_stripe(k).v;
 107
 108         if (k.k->p.inode)
 109                 return "invalid stripe key";
 110
 111         if (bkey_val_bytes(k.k) < sizeof(*s))
 112                 return "incorrect value size";
 113
 114         if (bkey_val_bytes(k.k) < sizeof(*s) ||
 115             bkey_val_u64s(k.k) < stripe_val_u64s(s))
 116                 return "incorrect value size";
 117
 118         return bch2_bkey_ptrs_invalid(c, k);
 119 }
 120
 121 void bch2_stripe_to_text(struct printbuf *out, struct bch_fs *c,
 122                          struct bkey_s_c k)
 123 {
 124         const struct bch_stripe *s = bkey_s_c_to_stripe(k).v;
 125         unsigned i;
 126
 127         pr_buf(out, "algo %u sectors %u blocks %u:%u csum %u gran %u",
 128                s->algorithm,
 129                le16_to_cpu(s->sectors),
 130                s->nr_blocks - s->nr_redundant,
 131                s->nr_redundant,
 132                s->csum_type,
 133                1U << s->csum_granularity_bits);
 134
 135         for (i = 0; i < s->nr_blocks; i++)
 136                 pr_buf(out, " %u:%llu:%u", s->ptrs[i].dev,
 137                        (u64) s->ptrs[i].offset,
 138                        stripe_blockcount_get(s, i));
 139 }
 140
 141 static int ptr_matches_stripe(struct bch_fs *c,
 142                               struct bch_stripe *v,
 143                               const struct bch_extent_ptr *ptr)
 144 {
 145         unsigned i;
 146
 147         for (i = 0; i < v->nr_blocks - v->nr_redundant; i++) {
 148                 const struct bch_extent_ptr *ptr2 = v->ptrs + i;
 149
 150                 if (ptr->dev == ptr2->dev &&
 151                     ptr->gen == ptr2->gen &&
 152                     ptr->offset >= ptr2->offset &&
 153                     ptr->offset <  ptr2->offset + le16_to_cpu(v->sectors))
 154                         return i;
 155         }
 156
 157         return -1;
 158 }
 159
 160 static int extent_matches_stripe(struct bch_fs *c,
 161                                  struct bch_stripe *v,
 162                                  struct bkey_s_c k)
 163 {
 164
 165         switch (k.k->type) {
 166         case KEY_TYPE_extent: {
 167                 struct bkey_s_c_extent e = bkey_s_c_to_extent(k);
 168                 const struct bch_extent_ptr *ptr;
 169                 int idx;
 170
 171                 extent_for_each_ptr(e, ptr) {
 172                         idx = ptr_matches_stripe(c, v, ptr);
 173                         if (idx >= 0)
 174                                 return idx;
 175                 }
 176                 break;
 177         }
 178         }
 179
 180         return -1;
 181 }
 182
 183 static bool extent_has_stripe_ptr(struct bkey_s_c k, u64 idx)
 184 {
 185         switch (k.k->type) {
 186         case KEY_TYPE_extent: {
 187                 struct bkey_s_c_extent e = bkey_s_c_to_extent(k);
 188                 const union bch_extent_entry *entry;
 189
 190                 extent_for_each_entry(e, entry)
 191                         if (extent_entry_type(entry) ==
 192                             BCH_EXTENT_ENTRY_stripe_ptr &&
 193                             entry->stripe_ptr.idx == idx)
 194                                 return true;
 195
 196                 break;
 197         }
 198         }
 199
 200         return false;
 201 }
 202
 203 /* Checksumming: */
 204
 205 static void ec_generate_checksums(struct ec_stripe_buf *buf)
 206 {
 207         struct bch_stripe *v = &buf->key.v;
 208         unsigned csum_granularity = 1 << v->csum_granularity_bits;
 209         unsigned csums_per_device = stripe_csums_per_device(v);
 210         unsigned csum_bytes = bch_crc_bytes[v->csum_type];
 211         unsigned i, j;
 212
 213         if (!csum_bytes)
 214                 return;
 215
 216         BUG_ON(buf->offset);
 217         BUG_ON(buf->size != le16_to_cpu(v->sectors));
 218
 219         for (i = 0; i < v->nr_blocks; i++) {
 220                 for (j = 0; j < csums_per_device; j++) {
 221                         unsigned offset = j << v->csum_granularity_bits;
 222                         unsigned len = min(csum_granularity, buf->size - offset);
 223
 224                         struct bch_csum csum =
 225                                 bch2_checksum(NULL, v->csum_type,
 226                                               null_nonce(),
 227                                               buf->data[i] + (offset << 9),
 228                                               len << 9);
 229
 230                         memcpy(stripe_csum(v, i, j), &csum, csum_bytes);
 231                 }
 232         }
 233 }
 234
 235 static void ec_validate_checksums(struct bch_fs *c, struct ec_stripe_buf *buf)
 236 {
 237         struct bch_stripe *v = &buf->key.v;
 238         unsigned csum_granularity = 1 << v->csum_granularity_bits;
 239         unsigned csum_bytes = bch_crc_bytes[v->csum_type];
 240         unsigned i;
 241
 242         if (!csum_bytes)
 243                 return;
 244
 245         for (i = 0; i < v->nr_blocks; i++) {
 246                 unsigned offset = buf->offset;
 247                 unsigned end = buf->offset + buf->size;
 248
 249                 if (!test_bit(i, buf->valid))
 250                         continue;
 251
 252                 while (offset < end) {
 253                         unsigned j = offset >> v->csum_granularity_bits;
 254                         unsigned len = min(csum_granularity, end - offset);
 255                         struct bch_csum csum;
 256
 257                         BUG_ON(offset & (csum_granularity - 1));
 258                         BUG_ON(offset + len != le16_to_cpu(v->sectors) &&
 259                                ((offset + len) & (csum_granularity - 1)));
 260
 261                         csum = bch2_checksum(NULL, v->csum_type,
 262                                              null_nonce(),
 263                                              buf->data[i] + ((offset - buf->offset) << 9),
 264                                              len << 9);
 265
 266                         if (memcmp(stripe_csum(v, i, j), &csum, csum_bytes)) {
 267                                 __bcache_io_error(c,
 268                                         "checksum error while doing reconstruct read (%u:%u)",
 269                                         i, j);
 270                                 clear_bit(i, buf->valid);
 271                                 break;
 272                         }
 273
 274                         offset += len;
 275                 }
 276         }
 277 }
 278
 279 /* Erasure coding: */
 280
 281 static void ec_generate_ec(struct ec_stripe_buf *buf)
 282 {
 283         struct bch_stripe *v = &buf->key.v;
 284         unsigned nr_data = v->nr_blocks - v->nr_redundant;
 285         unsigned bytes = le16_to_cpu(v->sectors) << 9;
 286
 287         raid_gen(nr_data, v->nr_redundant, bytes, buf->data);
 288 }
 289
 290 static unsigned __ec_nr_failed(struct ec_stripe_buf *buf, unsigned nr)
 291 {
 292         return nr - bitmap_weight(buf->valid, nr);
 293 }
 294
 295 static unsigned ec_nr_failed(struct ec_stripe_buf *buf)
 296 {
 297         return __ec_nr_failed(buf, buf->key.v.nr_blocks);
 298 }
 299
 300 static int ec_do_recov(struct bch_fs *c, struct ec_stripe_buf *buf)
 301 {
 302         struct bch_stripe *v = &buf->key.v;
 303         unsigned i, failed[EC_STRIPE_MAX], nr_failed = 0;
 304         unsigned nr_data = v->nr_blocks - v->nr_redundant;
 305         unsigned bytes = buf->size << 9;
 306
 307         if (ec_nr_failed(buf) > v->nr_redundant) {
 308                 __bcache_io_error(c,
 309                         "error doing reconstruct read: unable to read enough blocks");
 310                 return -1;
 311         }
 312
 313         for (i = 0; i < nr_data; i++)
 314                 if (!test_bit(i, buf->valid))
 315                         failed[nr_failed++] = i;
 316
 317         raid_rec(nr_failed, failed, nr_data, v->nr_redundant, bytes, buf->data);
 318         return 0;
 319 }
 320
 321 /* IO: */
 322
 323 static void ec_block_endio(struct bio *bio)
 324 {
 325         struct ec_bio *ec_bio = container_of(bio, struct ec_bio, bio);
 326         struct bch_dev *ca = ec_bio->ca;
 327         struct closure *cl = bio->bi_private;
 328
 329         if (bch2_dev_io_err_on(bio->bi_status, ca, "erasure coding %s: %s",
 330                                bio_data_dir(bio) ? "write" : "read",
 331                                bch2_blk_status_to_str(bio->bi_status)))
 332                 clear_bit(ec_bio->idx, ec_bio->buf->valid);
 333
 334         bio_put(&ec_bio->bio);
 335         percpu_ref_put(&ca->io_ref);
 336         closure_put(cl);
 337 }
 338
 339 static void ec_block_io(struct bch_fs *c, struct ec_stripe_buf *buf,
 340                         unsigned rw, unsigned idx, struct closure *cl)
 341 {
 342         struct bch_stripe *v = &buf->key.v;
 343         unsigned offset = 0, bytes = buf->size << 9;
 344         struct bch_extent_ptr *ptr = &v->ptrs[idx];
 345         struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
 346
 347         if (!bch2_dev_get_ioref(ca, rw)) {
 348                 clear_bit(idx, buf->valid);
 349                 return;
 350         }
 351
 352         while (offset < bytes) {
 353                 unsigned nr_iovecs = min_t(size_t, BIO_MAX_PAGES,
 354                                            DIV_ROUND_UP(bytes, PAGE_SIZE));
 355                 unsigned b = min_t(size_t, bytes - offset,
 356                                    nr_iovecs << PAGE_SHIFT);
 357                 struct ec_bio *ec_bio;
 358
 359                 ec_bio = container_of(bio_alloc_bioset(GFP_KERNEL, nr_iovecs,
 360                                                        &c->ec_bioset),
 361                                       struct ec_bio, bio);
 362
 363                 ec_bio->ca                      = ca;
 364                 ec_bio->buf                     = buf;
 365                 ec_bio->idx                     = idx;
 366
 367                 bio_set_dev(&ec_bio->bio, ca->disk_sb.bdev);
 368                 bio_set_op_attrs(&ec_bio->bio, rw, 0);
 369
 370                 ec_bio->bio.bi_iter.bi_sector   = ptr->offset + buf->offset + (offset >> 9);
 371                 ec_bio->bio.bi_end_io           = ec_block_endio;
 372                 ec_bio->bio.bi_private          = cl;
 373
 374                 bch2_bio_map(&ec_bio->bio, buf->data[idx] + offset, b);
 375
 376                 closure_get(cl);
 377                 percpu_ref_get(&ca->io_ref);
 378
 379                 submit_bio(&ec_bio->bio);
 380
 381                 offset += b;
 382         }
 383
 384         percpu_ref_put(&ca->io_ref);
 385 }
 386
 387 /* recovery read path: */
 388 int bch2_ec_read_extent(struct bch_fs *c, struct bch_read_bio *rbio)
 389 {
 390         struct btree_trans trans;
 391         struct btree_iter *iter;
 392         struct ec_stripe_buf *buf;
 393         struct closure cl;
 394         struct bkey_s_c k;
 395         struct bch_stripe *v;
 396         unsigned stripe_idx;
 397         unsigned offset, end;
 398         unsigned i, nr_data, csum_granularity;
 399         int ret = 0, idx;
 400
 401         closure_init_stack(&cl);
 402
 403         BUG_ON(!rbio->pick.has_ec);
 404
 405         stripe_idx = rbio->pick.ec.idx;
 406
 407         buf = kzalloc(sizeof(*buf), GFP_NOIO);
 408         if (!buf)
 409                 return -ENOMEM;
 410
 411         bch2_trans_init(&trans, c, 0, 0);
 412
 413         iter = bch2_trans_get_iter(&trans, BTREE_ID_EC,
 414                                    POS(0, stripe_idx),
 415                                    BTREE_ITER_SLOTS);
 416         k = bch2_btree_iter_peek_slot(iter);
 417         if (bkey_err(k) || k.k->type != KEY_TYPE_stripe) {
 418                 __bcache_io_error(c,
 419                         "error doing reconstruct read: stripe not found");
 420                 kfree(buf);
 421                 return bch2_trans_exit(&trans) ?: -EIO;
 422         }
 423
 424         bkey_reassemble(&buf->key.k_i, k);
 425         bch2_trans_exit(&trans);
 426
 427         v = &buf->key.v;
 428
 429         nr_data = v->nr_blocks - v->nr_redundant;
 430
 431         idx = ptr_matches_stripe(c, v, &rbio->pick.ptr);
 432         BUG_ON(idx < 0);
 433
 434         csum_granularity = 1U << v->csum_granularity_bits;
 435
 436         offset  = rbio->bio.bi_iter.bi_sector - v->ptrs[idx].offset;
 437         end     = offset + bio_sectors(&rbio->bio);
 438
 439         BUG_ON(end > le16_to_cpu(v->sectors));
 440
 441         buf->offset     = round_down(offset, csum_granularity);
 442         buf->size       = min_t(unsigned, le16_to_cpu(v->sectors),
 443                                 round_up(end, csum_granularity)) - buf->offset;
 444
 445         for (i = 0; i < v->nr_blocks; i++) {
 446                 buf->data[i] = kmalloc(buf->size << 9, GFP_NOIO);
 447                 if (!buf->data[i]) {
 448                         ret = -ENOMEM;
 449                         goto err;
 450                 }
 451         }
 452
 453         memset(buf->valid, 0xFF, sizeof(buf->valid));
 454
 455         for (i = 0; i < v->nr_blocks; i++) {
 456                 struct bch_extent_ptr *ptr = v->ptrs + i;
 457                 struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
 458
 459                 if (ptr_stale(ca, ptr)) {
 460                         __bcache_io_error(c,
 461                                           "error doing reconstruct read: stale pointer");
 462                         clear_bit(i, buf->valid);
 463                         continue;
 464                 }
 465
 466                 ec_block_io(c, buf, REQ_OP_READ, i, &cl);
 467         }
 468
 469         closure_sync(&cl);
 470
 471         if (ec_nr_failed(buf) > v->nr_redundant) {
 472                 __bcache_io_error(c,
 473                         "error doing reconstruct read: unable to read enough blocks");
 474                 ret = -EIO;
 475                 goto err;
 476         }
 477
 478         ec_validate_checksums(c, buf);
 479
 480         ret = ec_do_recov(c, buf);
 481         if (ret)
 482                 goto err;
 483
 484         memcpy_to_bio(&rbio->bio, rbio->bio.bi_iter,
 485                       buf->data[idx] + ((offset - buf->offset) << 9));
 486 err:
 487         for (i = 0; i < v->nr_blocks; i++)
 488                 kfree(buf->data[i]);
 489         kfree(buf);
 490         return ret;
 491 }
 492
 493 /* stripe bucket accounting: */
 494
 495 static int __ec_stripe_mem_alloc(struct bch_fs *c, size_t idx, gfp_t gfp)
 496 {
 497         ec_stripes_heap n, *h = &c->ec_stripes_heap;
 498
 499         if (idx >= h->size) {
 500                 if (!init_heap(&n, max(1024UL, roundup_pow_of_two(idx + 1)), gfp))
 501                         return -ENOMEM;
 502
 503                 spin_lock(&c->ec_stripes_heap_lock);
 504                 if (n.size > h->size) {
 505                         memcpy(n.data, h->data, h->used * sizeof(h->data[0]));
 506                         n.used = h->used;
 507                         swap(*h, n);
 508                 }
 509                 spin_unlock(&c->ec_stripes_heap_lock);
 510
 511                 free_heap(&n);
 512         }
 513
 514         if (!genradix_ptr_alloc(&c->stripes[0], idx, gfp))
 515                 return -ENOMEM;
 516
 517         if (c->gc_pos.phase != GC_PHASE_NOT_RUNNING &&
 518             !genradix_ptr_alloc(&c->stripes[1], idx, gfp))
 519                 return -ENOMEM;
 520
 521         return 0;
 522 }
 523
 524 static int ec_stripe_mem_alloc(struct bch_fs *c,
 525                                struct btree_iter *iter)
 526 {
 527         size_t idx = iter->pos.offset;
 528         int ret = 0;
 529
 530         if (!__ec_stripe_mem_alloc(c, idx, GFP_NOWAIT|__GFP_NOWARN))
 531                 return ret;
 532
 533         bch2_trans_unlock(iter->trans);
 534         ret = -EINTR;
 535
 536         if (!__ec_stripe_mem_alloc(c, idx, GFP_KERNEL))
 537                 return ret;
 538
 539         return -ENOMEM;
 540 }
 541
 542 static ssize_t stripe_idx_to_delete(struct bch_fs *c)
 543 {
 544         ec_stripes_heap *h = &c->ec_stripes_heap;
 545
 546         return h->used && h->data[0].blocks_nonempty == 0
 547                 ? h->data[0].idx : -1;
 548 }
 549
 550 static inline int ec_stripes_heap_cmp(ec_stripes_heap *h,
 551                                       struct ec_stripe_heap_entry l,
 552                                       struct ec_stripe_heap_entry r)
 553 {
 554         return ((l.blocks_nonempty > r.blocks_nonempty) -
 555                 (l.blocks_nonempty < r.blocks_nonempty));
 556 }
 557
 558 static inline void ec_stripes_heap_set_backpointer(ec_stripes_heap *h,
 559                                                    size_t i)
 560 {
 561         struct bch_fs *c = container_of(h, struct bch_fs, ec_stripes_heap);
 562
 563         genradix_ptr(&c->stripes[0], h->data[i].idx)->heap_idx = i;
 564 }
 565
 566 static void heap_verify_backpointer(struct bch_fs *c, size_t idx)
 567 {
 568         ec_stripes_heap *h = &c->ec_stripes_heap;
 569         struct stripe *m = genradix_ptr(&c->stripes[0], idx);
 570
 571         BUG_ON(!m->alive);
 572         BUG_ON(m->heap_idx >= h->used);
 573         BUG_ON(h->data[m->heap_idx].idx != idx);
 574 }
 575
 576 void bch2_stripes_heap_del(struct bch_fs *c,
 577                            struct stripe *m, size_t idx)
 578 {
 579         if (!m->on_heap)
 580                 return;
 581
 582         m->on_heap = false;
 583
 584         heap_verify_backpointer(c, idx);
 585
 586         heap_del(&c->ec_stripes_heap, m->heap_idx,
 587                  ec_stripes_heap_cmp,
 588                  ec_stripes_heap_set_backpointer);
 589 }
 590
 591 void bch2_stripes_heap_insert(struct bch_fs *c,
 592                               struct stripe *m, size_t idx)
 593 {
 594         if (m->on_heap)
 595                 return;
 596
 597         BUG_ON(heap_full(&c->ec_stripes_heap));
 598
 599         m->on_heap = true;
 600
 601         heap_add(&c->ec_stripes_heap, ((struct ec_stripe_heap_entry) {
 602                         .idx = idx,
 603                         .blocks_nonempty = m->blocks_nonempty,
 604                 }),
 605                  ec_stripes_heap_cmp,
 606                  ec_stripes_heap_set_backpointer);
 607
 608         heap_verify_backpointer(c, idx);
 609 }
 610
 611 void bch2_stripes_heap_update(struct bch_fs *c,
 612                               struct stripe *m, size_t idx)
 613 {
 614         ec_stripes_heap *h = &c->ec_stripes_heap;
 615         size_t i;
 616
 617         if (!m->on_heap)
 618                 return;
 619
 620         heap_verify_backpointer(c, idx);
 621
 622         h->data[m->heap_idx].blocks_nonempty = m->blocks_nonempty;
 623
 624         i = m->heap_idx;
 625         heap_sift_up(h,   i, ec_stripes_heap_cmp,
 626                      ec_stripes_heap_set_backpointer);
 627         heap_sift_down(h, i, ec_stripes_heap_cmp,
 628                        ec_stripes_heap_set_backpointer);
 629
 630         heap_verify_backpointer(c, idx);
 631
 632         if (stripe_idx_to_delete(c) >= 0 &&
 633             !percpu_ref_is_dying(&c->writes))
 634                 schedule_work(&c->ec_stripe_delete_work);
 635 }
 636
 637 /* stripe deletion */
 638
 639 static int ec_stripe_delete(struct bch_fs *c, size_t idx)
 640 {
 641         //pr_info("deleting stripe %zu", idx);
 642         return bch2_btree_delete_range(c, BTREE_ID_EC,
 643                                        POS(0, idx),
 644                                        POS(0, idx + 1),
 645                                        NULL);
 646 }
 647
 648 static void ec_stripe_delete_work(struct work_struct *work)
 649 {
 650         struct bch_fs *c =
 651                 container_of(work, struct bch_fs, ec_stripe_delete_work);
 652         ssize_t idx;
 653
 654         while (1) {
 655                 spin_lock(&c->ec_stripes_heap_lock);
 656                 idx = stripe_idx_to_delete(c);
 657                 if (idx < 0) {
 658                         spin_unlock(&c->ec_stripes_heap_lock);
 659                         break;
 660                 }
 661
 662                 bch2_stripes_heap_del(c, genradix_ptr(&c->stripes[0], idx), idx);
 663                 spin_unlock(&c->ec_stripes_heap_lock);
 664
 665                 if (ec_stripe_delete(c, idx))
 666                         break;
 667         }
 668 }
 669
 670 /* stripe creation: */
 671
 672 static int ec_stripe_bkey_insert(struct bch_fs *c,
 673                                  struct bkey_i_stripe *stripe)
 674 {
 675         struct btree_trans trans;
 676         struct btree_iter *iter;
 677         struct bkey_s_c k;
 678         struct bpos start_pos = POS(0, c->ec_stripe_hint);
 679         int ret;
 680
 681         bch2_trans_init(&trans, c, 0, 0);
 682 retry:
 683         bch2_trans_begin(&trans);
 684
 685         for_each_btree_key(&trans, iter, BTREE_ID_EC, start_pos,
 686                            BTREE_ITER_SLOTS|BTREE_ITER_INTENT, k, ret) {
 687                 if (bkey_cmp(k.k->p, POS(0, U32_MAX)) > 0) {
 688                         if (start_pos.offset) {
 689                                 start_pos = POS_MIN;
 690                                 bch2_btree_iter_set_pos(iter, start_pos);
 691                                 continue;
 692                         }
 693
 694                         ret = -ENOSPC;
 695                         break;
 696                 }
 697
 698                 if (bkey_deleted(k.k))
 699                         goto found_slot;
 700         }
 701
 702         goto err;
 703 found_slot:
 704         start_pos = iter->pos;
 705
 706         ret = ec_stripe_mem_alloc(c, iter);
 707         if (ret)
 708                 goto err;
 709
 710         stripe->k.p = iter->pos;
 711
 712         bch2_trans_update(&trans, iter, &stripe->k_i, 0);
 713
 714         ret = bch2_trans_commit(&trans, NULL, NULL,
 715                                 BTREE_INSERT_NOFAIL);
 716 err:
 717         bch2_trans_iter_put(&trans, iter);
 718
 719         if (ret == -EINTR)
 720                 goto retry;
 721
 722         c->ec_stripe_hint = ret ? start_pos.offset : start_pos.offset + 1;
 723         bch2_trans_exit(&trans);
 724
 725         return ret;
 726 }
 727
 728 static void extent_stripe_ptr_add(struct bkey_s_extent e,
 729                                   struct ec_stripe_buf *s,
 730                                   struct bch_extent_ptr *ptr,
 731                                   unsigned block)
 732 {
 733         struct bch_extent_stripe_ptr *dst = (void *) ptr;
 734         union bch_extent_entry *end = extent_entry_last(e);
 735
 736         memmove_u64s_up(dst + 1, dst, (u64 *) end - (u64 *) dst);
 737         e.k->u64s += sizeof(*dst) / sizeof(u64);
 738
 739         *dst = (struct bch_extent_stripe_ptr) {
 740                 .type = 1 << BCH_EXTENT_ENTRY_stripe_ptr,
 741                 .block          = block,
 742                 .idx            = s->key.k.p.offset,
 743         };
 744 }
 745
 746 static int ec_stripe_update_ptrs(struct bch_fs *c,
 747                                  struct ec_stripe_buf *s,
 748                                  struct bkey *pos)
 749 {
 750         struct btree_trans trans;
 751         struct btree_iter *iter;
 752         struct bkey_s_c k;
 753         struct bkey_s_extent e;
 754         struct bkey_on_stack sk;
 755         int ret = 0, dev, idx;
 756
 757         bkey_on_stack_init(&sk);
 758         bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);
 759
 760         /* XXX this doesn't support the reflink btree */
 761
 762         iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS,
 763                                    bkey_start_pos(pos),
 764                                    BTREE_ITER_INTENT);
 765
 766         while ((k = bch2_btree_iter_peek(iter)).k &&
 767                !(ret = bkey_err(k)) &&
 768                bkey_cmp(bkey_start_pos(k.k), pos->p) < 0) {
 769                 struct bch_extent_ptr *ptr, *ec_ptr = NULL;
 770
 771                 if (extent_has_stripe_ptr(k, s->key.k.p.offset)) {
 772                         bch2_btree_iter_next(iter);
 773                         continue;
 774                 }
 775
 776                 idx = extent_matches_stripe(c, &s->key.v, k);
 777                 if (idx < 0) {
 778                         bch2_btree_iter_next(iter);
 779                         continue;
 780                 }
 781
 782                 dev = s->key.v.ptrs[idx].dev;
 783
 784                 bkey_on_stack_reassemble(&sk, c, k);
 785                 e = bkey_i_to_s_extent(sk.k);
 786
 787                 bch2_bkey_drop_ptrs(e.s, ptr, ptr->dev != dev);
 788                 ec_ptr = (void *) bch2_bkey_has_device(e.s_c, dev);
 789                 BUG_ON(!ec_ptr);
 790
 791                 extent_stripe_ptr_add(e, s, ec_ptr, idx);
 792
 793                 bch2_btree_iter_set_pos(iter, bkey_start_pos(&sk.k->k));
 794                 bch2_trans_update(&trans, iter, sk.k, 0);
 795
 796                 ret = bch2_trans_commit(&trans, NULL, NULL,
 797                                         BTREE_INSERT_NOFAIL|
 798                                         BTREE_INSERT_USE_RESERVE);
 799                 if (ret == -EINTR)
 800                         ret = 0;
 801                 if (ret)
 802                         break;
 803         }
 804
 805         bch2_trans_exit(&trans);
 806         bkey_on_stack_exit(&sk, c);
 807
 808         return ret;
 809 }
 810
 811 /*
 812  * data buckets of new stripe all written: create the stripe
 813  */
 814 static void ec_stripe_create(struct ec_stripe_new *s)
 815 {
 816         struct bch_fs *c = s->c;
 817         struct open_bucket *ob;
 818         struct bkey_i *k;
 819         struct stripe *m;
 820         struct bch_stripe *v = &s->stripe.key.v;
 821         unsigned i, nr_data = v->nr_blocks - v->nr_redundant;
 822         struct closure cl;
 823         int ret;
 824
 825         BUG_ON(s->h->s == s);
 826
 827         closure_init_stack(&cl);
 828
 829         if (s->err) {
 830                 if (s->err != -EROFS)
 831                         bch_err(c, "error creating stripe: error writing data buckets");
 832                 goto err;
 833         }
 834
 835         BUG_ON(!s->allocated);
 836
 837         if (!percpu_ref_tryget(&c->writes))
 838                 goto err;
 839
 840         BUG_ON(bitmap_weight(s->blocks_allocated,
 841                              s->blocks.nr) != s->blocks.nr);
 842
 843         ec_generate_ec(&s->stripe);
 844
 845         ec_generate_checksums(&s->stripe);
 846
 847         /* write p/q: */
 848         for (i = nr_data; i < v->nr_blocks; i++)
 849                 ec_block_io(c, &s->stripe, REQ_OP_WRITE, i, &cl);
 850
 851         closure_sync(&cl);
 852
 853         for (i = nr_data; i < v->nr_blocks; i++)
 854                 if (!test_bit(i, s->stripe.valid)) {
 855                         bch_err(c, "error creating stripe: error writing redundancy buckets");
 856                         goto err_put_writes;
 857                 }
 858
 859         ret = s->existing_stripe
 860                 ? bch2_btree_insert(c, BTREE_ID_EC, &s->stripe.key.k_i,
 861                                     NULL, NULL, BTREE_INSERT_NOFAIL)
 862                 : ec_stripe_bkey_insert(c, &s->stripe.key);
 863         if (ret) {
 864                 bch_err(c, "error creating stripe: error creating stripe key");
 865                 goto err_put_writes;
 866         }
 867
 868         for_each_keylist_key(&s->keys, k) {
 869                 ret = ec_stripe_update_ptrs(c, &s->stripe, &k->k);
 870                 if (ret) {
 871                         bch_err(c, "error creating stripe: error updating pointers");
 872                         break;
 873                 }
 874         }
 875
 876         spin_lock(&c->ec_stripes_heap_lock);
 877         m = genradix_ptr(&c->stripes[0], s->stripe.key.k.p.offset);
 878 #if 0
 879         pr_info("created a %s stripe %llu",
 880                 s->existing_stripe ? "existing" : "new",
 881                 s->stripe.key.k.p.offset);
 882 #endif
 883         BUG_ON(m->on_heap);
 884         bch2_stripes_heap_insert(c, m, s->stripe.key.k.p.offset);
 885         spin_unlock(&c->ec_stripes_heap_lock);
 886 err_put_writes:
 887         percpu_ref_put(&c->writes);
 888 err:
 889         open_bucket_for_each(c, &s->blocks, ob, i) {
 890                 ob->ec = NULL;
 891                 __bch2_open_bucket_put(c, ob);
 892         }
 893
 894         bch2_open_buckets_put(c, &s->parity);
 895
 896         bch2_keylist_free(&s->keys, s->inline_keys);
 897
 898         for (i = 0; i < s->stripe.key.v.nr_blocks; i++)
 899                 kvpfree(s->stripe.data[i], s->stripe.size << 9);
 900         kfree(s);
 901 }
 902
 903 static void ec_stripe_create_work(struct work_struct *work)
 904 {
 905         struct bch_fs *c = container_of(work,
 906                 struct bch_fs, ec_stripe_create_work);
 907         struct ec_stripe_new *s, *n;
 908 restart:
 909         mutex_lock(&c->ec_stripe_new_lock);
 910         list_for_each_entry_safe(s, n, &c->ec_stripe_new_list, list)
 911                 if (!atomic_read(&s->pin)) {
 912                         list_del(&s->list);
 913                         mutex_unlock(&c->ec_stripe_new_lock);
 914                         ec_stripe_create(s);
 915                         goto restart;
 916                 }
 917         mutex_unlock(&c->ec_stripe_new_lock);
 918 }
 919
 920 static void ec_stripe_new_put(struct bch_fs *c, struct ec_stripe_new *s)
 921 {
 922         BUG_ON(atomic_read(&s->pin) <= 0);
 923
 924         if (atomic_dec_and_test(&s->pin)) {
 925                 BUG_ON(!s->pending);
 926                 queue_work(system_long_wq, &c->ec_stripe_create_work);
 927         }
 928 }
 929
 930 static void ec_stripe_set_pending(struct bch_fs *c, struct ec_stripe_head *h)
 931 {
 932         struct ec_stripe_new *s = h->s;
 933
 934         BUG_ON(!s->allocated && !s->err);
 935
 936         h->s            = NULL;
 937         s->pending      = true;
 938
 939         mutex_lock(&c->ec_stripe_new_lock);
 940         list_add(&s->list, &c->ec_stripe_new_list);
 941         mutex_unlock(&c->ec_stripe_new_lock);
 942
 943         ec_stripe_new_put(c, s);
 944 }
 945
 946 /* have a full bucket - hand it off to be erasure coded: */
 947 void bch2_ec_bucket_written(struct bch_fs *c, struct open_bucket *ob)
 948 {
 949         struct ec_stripe_new *s = ob->ec;
 950
 951         if (ob->sectors_free)
 952                 s->err = -1;
 953
 954         ec_stripe_new_put(c, s);
 955 }
 956
 957 void bch2_ec_bucket_cancel(struct bch_fs *c, struct open_bucket *ob)
 958 {
 959         struct ec_stripe_new *s = ob->ec;
 960
 961         s->err = -EIO;
 962 }
 963
 964 void *bch2_writepoint_ec_buf(struct bch_fs *c, struct write_point *wp)
 965 {
 966         struct open_bucket *ob = ec_open_bucket(c, &wp->ptrs);
 967         struct bch_dev *ca;
 968         unsigned offset;
 969
 970         if (!ob)
 971                 return NULL;
 972
 973         ca      = bch_dev_bkey_exists(c, ob->ptr.dev);
 974         offset  = ca->mi.bucket_size - ob->sectors_free;
 975
 976         return ob->ec->stripe.data[ob->ec_idx] + (offset << 9);
 977 }
 978
 979 void bch2_ec_add_backpointer(struct bch_fs *c, struct write_point *wp,
 980                              struct bpos pos, unsigned sectors)
 981 {
 982         struct open_bucket *ob = ec_open_bucket(c, &wp->ptrs);
 983         struct ec_stripe_new *ec;
 984
 985         if (!ob)
 986                 return;
 987
 988         //pr_info("adding backpointer at %llu:%llu", pos.inode, pos.offset);
 989
 990         ec = ob->ec;
 991         mutex_lock(&ec->lock);
 992
 993         if (bch2_keylist_realloc(&ec->keys, ec->inline_keys,
 994                                  ARRAY_SIZE(ec->inline_keys),
 995                                  BKEY_U64s)) {
 996                 BUG();
 997         }
 998
 999         bkey_init(&ec->keys.top->k);
1000         ec->keys.top->k.p       = pos;
1001         bch2_key_resize(&ec->keys.top->k, sectors);
1002         bch2_keylist_push(&ec->keys);
1003
1004         mutex_unlock(&ec->lock);
1005 }
1006
1007 static int unsigned_cmp(const void *_l, const void *_r)
1008 {
1009         unsigned l = *((const unsigned *) _l);
1010         unsigned r = *((const unsigned *) _r);
1011
1012         return cmp_int(l, r);
1013 }
1014
1015 /* pick most common bucket size: */
1016 static unsigned pick_blocksize(struct bch_fs *c,
1017                                struct bch_devs_mask *devs)
1018 {
1019         struct bch_dev *ca;
1020         unsigned i, nr = 0, sizes[BCH_SB_MEMBERS_MAX];
1021         struct {
1022                 unsigned nr, size;
1023         } cur = { 0, 0 }, best = { 0, 0 };
1024
1025         for_each_member_device_rcu(ca, c, i, devs)
1026                 sizes[nr++] = ca->mi.bucket_size;
1027
1028         sort(sizes, nr, sizeof(unsigned), unsigned_cmp, NULL);
1029
1030         for (i = 0; i < nr; i++) {
1031                 if (sizes[i] != cur.size) {
1032                         if (cur.nr > best.nr)
1033                                 best = cur;
1034
1035                         cur.nr = 0;
1036                         cur.size = sizes[i];
1037                 }
1038
1039                 cur.nr++;
1040         }
1041
1042         if (cur.nr > best.nr)
1043                 best = cur;
1044
1045         return best.size;
1046 }
1047
1048 static bool may_create_new_stripe(struct bch_fs *c)
1049 {
1050         return false;
1051 }
1052
1053 static void ec_stripe_key_init(struct bch_fs *c,
1054                                struct bkey_i_stripe *s,
1055                                unsigned nr_data,
1056                                unsigned nr_parity,
1057                                unsigned stripe_size)
1058 {
1059         unsigned u64s;
1060
1061         bkey_stripe_init(&s->k_i);
1062         s->v.sectors                    = cpu_to_le16(stripe_size);
1063         s->v.algorithm                  = 0;
1064         s->v.nr_blocks                  = nr_data + nr_parity;
1065         s->v.nr_redundant               = nr_parity;
1066         s->v.csum_granularity_bits      = ilog2(c->sb.encoded_extent_max);
1067         s->v.csum_type                  = BCH_CSUM_CRC32C;
1068         s->v.pad                        = 0;
1069
1070         while ((u64s = stripe_val_u64s(&s->v)) > BKEY_VAL_U64s_MAX) {
1071                 BUG_ON(1 << s->v.csum_granularity_bits >=
1072                        le16_to_cpu(s->v.sectors) ||
1073                        s->v.csum_granularity_bits == U8_MAX);
1074                 s->v.csum_granularity_bits++;
1075         }
1076
1077         set_bkey_val_u64s(&s->k, u64s);
1078 }
1079
1080 static int ec_new_stripe_alloc(struct bch_fs *c, struct ec_stripe_head *h)
1081 {
1082         struct ec_stripe_new *s;
1083         unsigned i;
1084
1085         lockdep_assert_held(&h->lock);
1086
1087         s = kzalloc(sizeof(*s), GFP_KERNEL);
1088         if (!s)
1089                 return -ENOMEM;
1090
1091         mutex_init(&s->lock);
1092         atomic_set(&s->pin, 1);
1093         s->c            = c;
1094         s->h            = h;
1095         s->nr_data      = min_t(unsigned, h->nr_active_devs,
1096                                 EC_STRIPE_MAX) - h->redundancy;
1097         s->nr_parity    = h->redundancy;
1098
1099         bch2_keylist_init(&s->keys, s->inline_keys);
1100
1101         s->stripe.offset        = 0;
1102         s->stripe.size          = h->blocksize;
1103         memset(s->stripe.valid, 0xFF, sizeof(s->stripe.valid));
1104
1105         ec_stripe_key_init(c, &s->stripe.key, s->nr_data,
1106                            s->nr_parity, h->blocksize);
1107
1108         for (i = 0; i < s->stripe.key.v.nr_blocks; i++) {
1109                 s->stripe.data[i] = kvpmalloc(s->stripe.size << 9, GFP_KERNEL);
1110                 if (!s->stripe.data[i])
1111                         goto err;
1112         }
1113
1114         h->s = s;
1115
1116         return 0;
1117 err:
1118         for (i = 0; i < s->stripe.key.v.nr_blocks; i++)
1119                 kvpfree(s->stripe.data[i], s->stripe.size << 9);
1120         kfree(s);
1121         return -ENOMEM;
1122 }
1123
1124 static struct ec_stripe_head *
1125 ec_new_stripe_head_alloc(struct bch_fs *c, unsigned target,
1126                          unsigned algo, unsigned redundancy)
1127 {
1128         struct ec_stripe_head *h;
1129         struct bch_dev *ca;
1130         unsigned i;
1131
1132         h = kzalloc(sizeof(*h), GFP_KERNEL);
1133         if (!h)
1134                 return NULL;
1135
1136         mutex_init(&h->lock);
1137         mutex_lock(&h->lock);
1138
1139         h->target       = target;
1140         h->algo         = algo;
1141         h->redundancy   = redundancy;
1142
1143         rcu_read_lock();
1144         h->devs = target_rw_devs(c, BCH_DATA_user, target);
1145
1146         for_each_member_device_rcu(ca, c, i, &h->devs)
1147                 if (!ca->mi.durability)
1148                         __clear_bit(i, h->devs.d);
1149
1150         h->blocksize = pick_blocksize(c, &h->devs);
1151
1152         for_each_member_device_rcu(ca, c, i, &h->devs)
1153                 if (ca->mi.bucket_size == h->blocksize)
1154                         h->nr_active_devs++;
1155
1156         rcu_read_unlock();
1157         list_add(&h->list, &c->ec_stripe_head_list);
1158         return h;
1159 }
1160
1161 void bch2_ec_stripe_head_put(struct bch_fs *c, struct ec_stripe_head *h)
1162 {
1163         if (h->s &&
1164             h->s->allocated &&
1165             bitmap_weight(h->s->blocks_allocated,
1166                           h->s->blocks.nr) == h->s->blocks.nr)
1167                 ec_stripe_set_pending(c, h);
1168
1169         mutex_unlock(&h->lock);
1170 }
1171
1172 struct ec_stripe_head *__bch2_ec_stripe_head_get(struct bch_fs *c,
1173                                                unsigned target,
1174                                                unsigned algo,
1175                                                unsigned redundancy)
1176 {
1177         struct ec_stripe_head *h;
1178
1179         if (!redundancy)
1180                 return NULL;
1181
1182         mutex_lock(&c->ec_stripe_head_lock);
1183         list_for_each_entry(h, &c->ec_stripe_head_list, list)
1184                 if (h->target           == target &&
1185                     h->algo             == algo &&
1186                     h->redundancy       == redundancy) {
1187                         mutex_lock(&h->lock);
1188                         goto found;
1189                 }
1190
1191         h = ec_new_stripe_head_alloc(c, target, algo, redundancy);
1192 found:
1193         mutex_unlock(&c->ec_stripe_head_lock);
1194         return h;
1195 }
1196
1197 /*
1198  * XXX: use a higher watermark for allocating open buckets here:
1199  */
1200 static int new_stripe_alloc_buckets(struct bch_fs *c, struct ec_stripe_head *h)
1201 {
1202         struct bch_devs_mask devs;
1203         struct open_bucket *ob;
1204         unsigned i, nr_have, nr_data =
1205                 min_t(unsigned, h->nr_active_devs,
1206                       EC_STRIPE_MAX) - h->redundancy;
1207         bool have_cache = true;
1208         int ret = 0;
1209
1210         devs = h->devs;
1211
1212         for_each_set_bit(i, h->s->blocks_allocated, EC_STRIPE_MAX) {
1213                 __clear_bit(h->s->stripe.key.v.ptrs[i].dev, devs.d);
1214                 --nr_data;
1215         }
1216
1217         BUG_ON(h->s->blocks.nr > nr_data);
1218         BUG_ON(h->s->parity.nr > h->redundancy);
1219
1220         open_bucket_for_each(c, &h->s->parity, ob, i)
1221                 __clear_bit(ob->ptr.dev, devs.d);
1222         open_bucket_for_each(c, &h->s->blocks, ob, i)
1223                 __clear_bit(ob->ptr.dev, devs.d);
1224
1225         percpu_down_read(&c->mark_lock);
1226         rcu_read_lock();
1227
1228         if (h->s->parity.nr < h->redundancy) {
1229                 nr_have = h->s->parity.nr;
1230
1231                 ret = bch2_bucket_alloc_set(c, &h->s->parity,
1232                                             &h->parity_stripe,
1233                                             &devs,
1234                                             h->redundancy,
1235                                             &nr_have,
1236                                             &have_cache,
1237                                             RESERVE_NONE,
1238                                             0,
1239                                             NULL);
1240                 if (ret)
1241                         goto err;
1242         }
1243
1244         if (h->s->blocks.nr < nr_data) {
1245                 nr_have = h->s->blocks.nr;
1246
1247                 ret = bch2_bucket_alloc_set(c, &h->s->blocks,
1248                                             &h->block_stripe,
1249                                             &devs,
1250                                             nr_data,
1251                                             &nr_have,
1252                                             &have_cache,
1253                                             RESERVE_NONE,
1254                                             0,
1255                                             NULL);
1256                 if (ret)
1257                         goto err;
1258         }
1259 err:
1260         rcu_read_unlock();
1261         percpu_up_read(&c->mark_lock);
1262         return ret;
1263 }
1264
1265 /* XXX: doesn't obey target: */
1266 static s64 get_existing_stripe(struct bch_fs *c,
1267                                unsigned target,
1268                                unsigned algo,
1269                                unsigned redundancy)
1270 {
1271         ec_stripes_heap *h = &c->ec_stripes_heap;
1272         struct stripe *m;
1273         size_t heap_idx;
1274         u64 stripe_idx;
1275
1276         if (may_create_new_stripe(c))
1277                 return -1;
1278
1279         spin_lock(&c->ec_stripes_heap_lock);
1280         for (heap_idx = 0; heap_idx < h->used; heap_idx++) {
1281                 if (!h->data[heap_idx].blocks_nonempty)
1282                         continue;
1283
1284                 stripe_idx = h->data[heap_idx].idx;
1285                 m = genradix_ptr(&c->stripes[0], stripe_idx);
1286
1287                 if (m->algorithm        == algo &&
1288                     m->nr_redundant     == redundancy &&
1289                     m->blocks_nonempty  < m->nr_blocks - m->nr_redundant) {
1290                         bch2_stripes_heap_del(c, m, stripe_idx);
1291                         spin_unlock(&c->ec_stripes_heap_lock);
1292                         return stripe_idx;
1293                 }
1294         }
1295
1296         spin_unlock(&c->ec_stripes_heap_lock);
1297         return -1;
1298 }
1299
1300 static int get_stripe_key(struct bch_fs *c, u64 idx, struct ec_stripe_buf *stripe)
1301 {
1302         struct btree_trans trans;
1303         struct btree_iter *iter;
1304         struct bkey_s_c k;
1305         int ret;
1306
1307         bch2_trans_init(&trans, c, 0, 0);
1308         iter = bch2_trans_get_iter(&trans, BTREE_ID_EC, POS(0, idx), BTREE_ITER_SLOTS);
1309         k = bch2_btree_iter_peek_slot(iter);
1310         ret = bkey_err(k);
1311         if (!ret)
1312                 bkey_reassemble(&stripe->key.k_i, k);
1313         bch2_trans_exit(&trans);
1314
1315         return ret;
1316 }
1317
1318 struct ec_stripe_head *bch2_ec_stripe_head_get(struct bch_fs *c,
1319                                                unsigned target,
1320                                                unsigned algo,
1321                                                unsigned redundancy)
1322 {
1323         struct closure cl;
1324         struct ec_stripe_head *h;
1325         struct open_bucket *ob;
1326         unsigned i, data_idx = 0;
1327         s64 idx;
1328
1329         closure_init_stack(&cl);
1330
1331         h = __bch2_ec_stripe_head_get(c, target, algo, redundancy);
1332         if (!h)
1333                 return NULL;
1334
1335         if (!h->s && ec_new_stripe_alloc(c, h)) {
1336                 bch2_ec_stripe_head_put(c, h);
1337                 return NULL;
1338         }
1339
1340         if (!h->s->allocated) {
1341                 if (!h->s->existing_stripe &&
1342                     (idx = get_existing_stripe(c, target, algo, redundancy)) >= 0) {
1343                         //pr_info("got existing stripe %llu", idx);
1344
1345                         h->s->existing_stripe = true;
1346                         h->s->existing_stripe_idx = idx;
1347                         if (get_stripe_key(c, idx, &h->s->stripe)) {
1348                                 /* btree error */
1349                                 BUG();
1350                         }
1351
1352                         for (i = 0; i < h->s->stripe.key.v.nr_blocks; i++)
1353                                 if (stripe_blockcount_get(&h->s->stripe.key.v, i)) {
1354                                         __set_bit(i, h->s->blocks_allocated);
1355                                         ec_block_io(c, &h->s->stripe, READ, i, &cl);
1356                                 }
1357                 }
1358
1359                 if (new_stripe_alloc_buckets(c, h)) {
1360                         bch2_ec_stripe_head_put(c, h);
1361                         h = NULL;
1362                         goto out;
1363                 }
1364
1365                 open_bucket_for_each(c, &h->s->blocks, ob, i) {
1366                         data_idx = find_next_zero_bit(h->s->blocks_allocated,
1367                                                       h->s->nr_data, data_idx);
1368                         BUG_ON(data_idx >= h->s->nr_data);
1369
1370                         h->s->stripe.key.v.ptrs[data_idx] = ob->ptr;
1371                         h->s->data_block_idx[i] = data_idx;
1372                         data_idx++;
1373                 }
1374
1375                 open_bucket_for_each(c, &h->s->parity, ob, i)
1376                         h->s->stripe.key.v.ptrs[h->s->nr_data + i] = ob->ptr;
1377
1378                 //pr_info("new stripe, blocks_allocated %lx", h->s->blocks_allocated[0]);
1379                 h->s->allocated = true;
1380         }
1381 out:
1382         closure_sync(&cl);
1383         return h;
1384 }
1385
1386 void bch2_ec_stop_dev(struct bch_fs *c, struct bch_dev *ca)
1387 {
1388         struct ec_stripe_head *h;
1389         struct open_bucket *ob;
1390         unsigned i;
1391
1392         mutex_lock(&c->ec_stripe_head_lock);
1393         list_for_each_entry(h, &c->ec_stripe_head_list, list) {
1394
1395                 mutex_lock(&h->lock);
1396                 if (!h->s)
1397                         goto unlock;
1398
1399                 open_bucket_for_each(c, &h->s->blocks, ob, i)
1400                         if (ob->ptr.dev == ca->dev_idx)
1401                                 goto found;
1402                 open_bucket_for_each(c, &h->s->parity, ob, i)
1403                         if (ob->ptr.dev == ca->dev_idx)
1404                                 goto found;
1405                 goto unlock;
1406 found:
1407                 h->s->err = -EROFS;
1408                 ec_stripe_set_pending(c, h);
1409 unlock:
1410                 mutex_unlock(&h->lock);
1411         }
1412         mutex_unlock(&c->ec_stripe_head_lock);
1413 }
1414
1415 static int __bch2_stripe_write_key(struct btree_trans *trans,
1416                                    struct btree_iter *iter,
1417                                    struct stripe *m,
1418                                    size_t idx,
1419                                    struct bkey_i_stripe *new_key)
1420 {
1421         struct bch_fs *c = trans->c;
1422         struct bkey_s_c k;
1423         unsigned i;
1424         int ret;
1425
1426         bch2_btree_iter_set_pos(iter, POS(0, idx));
1427
1428         k = bch2_btree_iter_peek_slot(iter);
1429         ret = bkey_err(k);
1430         if (ret)
1431                 return ret;
1432
1433         if (k.k->type != KEY_TYPE_stripe)
1434                 return -EIO;
1435
1436         bkey_reassemble(&new_key->k_i, k);
1437
1438         spin_lock(&c->ec_stripes_heap_lock);
1439
1440         for (i = 0; i < new_key->v.nr_blocks; i++)
1441                 stripe_blockcount_set(&new_key->v, i,
1442                                       m->block_sectors[i]);
1443         m->dirty = false;
1444
1445         spin_unlock(&c->ec_stripes_heap_lock);
1446
1447         bch2_trans_update(trans, iter, &new_key->k_i, 0);
1448         return 0;
1449 }
1450
1451 int bch2_stripes_write(struct bch_fs *c, unsigned flags)
1452 {
1453         struct btree_trans trans;
1454         struct btree_iter *iter;
1455         struct genradix_iter giter;
1456         struct bkey_i_stripe *new_key;
1457         struct stripe *m;
1458         int ret = 0;
1459
1460         new_key = kmalloc(255 * sizeof(u64), GFP_KERNEL);
1461         BUG_ON(!new_key);
1462
1463         bch2_trans_init(&trans, c, 0, 0);
1464
1465         iter = bch2_trans_get_iter(&trans, BTREE_ID_EC, POS_MIN,
1466                                    BTREE_ITER_SLOTS|BTREE_ITER_INTENT);
1467
1468         genradix_for_each(&c->stripes[0], giter, m) {
1469                 if (!m->dirty)
1470                         continue;
1471
1472                 ret = __bch2_trans_do(&trans, NULL, NULL,
1473                                       BTREE_INSERT_NOFAIL|flags,
1474                         __bch2_stripe_write_key(&trans, iter, m,
1475                                         giter.pos, new_key));
1476
1477                 if (ret)
1478                         break;
1479         }
1480
1481         bch2_trans_exit(&trans);
1482
1483         kfree(new_key);
1484
1485         return ret;
1486 }
1487
1488 static int bch2_stripes_read_fn(struct bch_fs *c, enum btree_id id,
1489                               unsigned level, struct bkey_s_c k)
1490 {
1491         int ret = 0;
1492
1493         if (k.k->type == KEY_TYPE_stripe) {
1494                 struct stripe *m;
1495
1496                 ret = __ec_stripe_mem_alloc(c, k.k->p.offset, GFP_KERNEL) ?:
1497                         bch2_mark_key(c, k, 0, 0, NULL, 0,
1498                                       BTREE_TRIGGER_NOATOMIC);
1499                 if (ret)
1500                         return ret;
1501
1502                 spin_lock(&c->ec_stripes_heap_lock);
1503                 m = genradix_ptr(&c->stripes[0], k.k->p.offset);
1504                 bch2_stripes_heap_insert(c, m, k.k->p.offset);
1505                 spin_unlock(&c->ec_stripes_heap_lock);
1506         }
1507
1508         return ret;
1509 }
1510
1511 int bch2_stripes_read(struct bch_fs *c, struct journal_keys *journal_keys)
1512 {
1513         int ret = bch2_btree_and_journal_walk(c, journal_keys, BTREE_ID_EC,
1514                                           NULL, bch2_stripes_read_fn);
1515         if (ret)
1516                 bch_err(c, "error reading stripes: %i", ret);
1517
1518         return ret;
1519 }
1520
1521 int bch2_ec_mem_alloc(struct bch_fs *c, bool gc)
1522 {
1523         struct btree_trans trans;
1524         struct btree_iter *iter;
1525         struct bkey_s_c k;
1526         size_t i, idx = 0;
1527         int ret = 0;
1528
1529         bch2_trans_init(&trans, c, 0, 0);
1530
1531         iter = bch2_trans_get_iter(&trans, BTREE_ID_EC, POS(0, U64_MAX), 0);
1532
1533         k = bch2_btree_iter_prev(iter);
1534         if (!IS_ERR_OR_NULL(k.k))
1535                 idx = k.k->p.offset + 1;
1536         ret = bch2_trans_exit(&trans);
1537         if (ret)
1538                 return ret;
1539
1540         if (!idx)
1541                 return 0;
1542
1543         if (!gc &&
1544             !init_heap(&c->ec_stripes_heap, roundup_pow_of_two(idx),
1545                        GFP_KERNEL))
1546                 return -ENOMEM;
1547 #if 0
1548         ret = genradix_prealloc(&c->stripes[gc], idx, GFP_KERNEL);
1549 #else
1550         for (i = 0; i < idx; i++)
1551                 if (!genradix_ptr_alloc(&c->stripes[gc], i, GFP_KERNEL))
1552                         return -ENOMEM;
1553 #endif
1554         return 0;
1555 }
1556
1557 void bch2_stripes_heap_to_text(struct printbuf *out, struct bch_fs *c)
1558 {
1559         ec_stripes_heap *h = &c->ec_stripes_heap;
1560         struct stripe *m;
1561         size_t i;
1562
1563         spin_lock(&c->ec_stripes_heap_lock);
1564         for (i = 0; i < min(h->used, 20UL); i++) {
1565                 m = genradix_ptr(&c->stripes[0], h->data[i].idx);
1566
1567                 pr_buf(out, "%zu %u/%u+%u\n", h->data[i].idx,
1568                        h->data[i].blocks_nonempty,
1569                        m->nr_blocks - m->nr_redundant,
1570                        m->nr_redundant);
1571         }
1572         spin_unlock(&c->ec_stripes_heap_lock);
1573 }
1574
1575 void bch2_new_stripes_to_text(struct printbuf *out, struct bch_fs *c)
1576 {
1577         struct ec_stripe_head *h;
1578         struct ec_stripe_new *s;
1579
1580         mutex_lock(&c->ec_stripe_head_lock);
1581         list_for_each_entry(h, &c->ec_stripe_head_list, list) {
1582                 pr_buf(out, "target %u algo %u redundancy %u:\n",
1583                        h->target, h->algo, h->redundancy);
1584
1585                 if (h->s)
1586                         pr_buf(out, "\tpending: blocks %u allocated %u\n",
1587                                h->s->blocks.nr,
1588                                bitmap_weight(h->s->blocks_allocated,
1589                                              h->s->blocks.nr));
1590         }
1591         mutex_unlock(&c->ec_stripe_head_lock);
1592
1593         mutex_lock(&c->ec_stripe_new_lock);
1594         list_for_each_entry(s, &c->ec_stripe_new_list, list) {
1595                 pr_buf(out, "\tin flight: blocks %u allocated %u pin %u\n",
1596                        s->blocks.nr,
1597                        bitmap_weight(s->blocks_allocated,
1598                                      s->blocks.nr),
1599                        atomic_read(&s->pin));
1600         }
1601         mutex_unlock(&c->ec_stripe_new_lock);
1602 }
1603
1604 void bch2_fs_ec_exit(struct bch_fs *c)
1605 {
1606         struct ec_stripe_head *h;
1607
1608         while (1) {
1609                 mutex_lock(&c->ec_stripe_head_lock);
1610                 h = list_first_entry_or_null(&c->ec_stripe_head_list,
1611                                              struct ec_stripe_head, list);
1612                 if (h)
1613                         list_del(&h->list);
1614                 mutex_unlock(&c->ec_stripe_head_lock);
1615                 if (!h)
1616                         break;
1617
1618                 BUG_ON(h->s);
1619                 kfree(h);
1620         }
1621
1622         BUG_ON(!list_empty(&c->ec_stripe_new_list));
1623
1624         free_heap(&c->ec_stripes_heap);
1625         genradix_free(&c->stripes[0]);
1626         bioset_exit(&c->ec_bioset);
1627 }
1628
1629 int bch2_fs_ec_init(struct bch_fs *c)
1630 {
1631         INIT_WORK(&c->ec_stripe_create_work, ec_stripe_create_work);
1632         INIT_WORK(&c->ec_stripe_delete_work, ec_stripe_delete_work);
1633
1634         return bioset_init(&c->ec_bioset, 1, offsetof(struct ec_bio, bio),
1635                            BIOSET_NEED_BVECS);
1636 }