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_buf.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 /* Stripe bufs: */
 204
 205 static void ec_stripe_buf_free(struct ec_stripe_buf *stripe)
 206 {
 207         unsigned i;
 208
 209         for (i = 0; i < stripe->key.v.nr_blocks; i++) {
 210                 kvpfree(stripe->data[i], stripe->size << 9);
 211                 stripe->data[i] = NULL;
 212         }
 213 }
 214
 215 static int ec_stripe_buf_alloc(struct ec_stripe_buf *stripe)
 216 {
 217         unsigned i;
 218
 219         memset(stripe->valid, 0xFF, sizeof(stripe->valid));
 220
 221         for (i = 0; i < stripe->key.v.nr_blocks; i++) {
 222                 stripe->data[i] = kvpmalloc(stripe->size << 9, GFP_KERNEL);
 223                 if (!stripe->data[i])
 224                         goto err;
 225         }
 226
 227         return 0;
 228 err:
 229         ec_stripe_buf_free(stripe);
 230         return -ENOMEM;
 231 }
 232
 233 /* Checksumming: */
 234
 235 static void ec_generate_checksums(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 csums_per_device = stripe_csums_per_device(v);
 240         unsigned csum_bytes = bch_crc_bytes[v->csum_type];
 241         unsigned i, j;
 242
 243         if (!csum_bytes)
 244                 return;
 245
 246         BUG_ON(buf->offset);
 247         BUG_ON(buf->size != le16_to_cpu(v->sectors));
 248
 249         for (i = 0; i < v->nr_blocks; i++) {
 250                 for (j = 0; j < csums_per_device; j++) {
 251                         unsigned offset = j << v->csum_granularity_bits;
 252                         unsigned len = min(csum_granularity, buf->size - offset);
 253
 254                         struct bch_csum csum =
 255                                 bch2_checksum(NULL, v->csum_type,
 256                                               null_nonce(),
 257                                               buf->data[i] + (offset << 9),
 258                                               len << 9);
 259
 260                         memcpy(stripe_csum(v, i, j), &csum, csum_bytes);
 261                 }
 262         }
 263 }
 264
 265 static void ec_validate_checksums(struct bch_fs *c, struct ec_stripe_buf *buf)
 266 {
 267         struct bch_stripe *v = &buf->key.v;
 268         unsigned csum_granularity = 1 << v->csum_granularity_bits;
 269         unsigned csum_bytes = bch_crc_bytes[v->csum_type];
 270         unsigned i;
 271
 272         if (!csum_bytes)
 273                 return;
 274
 275         for (i = 0; i < v->nr_blocks; i++) {
 276                 unsigned offset = buf->offset;
 277                 unsigned end = buf->offset + buf->size;
 278
 279                 if (!test_bit(i, buf->valid))
 280                         continue;
 281
 282                 while (offset < end) {
 283                         unsigned j = offset >> v->csum_granularity_bits;
 284                         unsigned len = min(csum_granularity, end - offset);
 285                         struct bch_csum csum;
 286
 287                         BUG_ON(offset & (csum_granularity - 1));
 288                         BUG_ON(offset + len != le16_to_cpu(v->sectors) &&
 289                                ((offset + len) & (csum_granularity - 1)));
 290
 291                         csum = bch2_checksum(NULL, v->csum_type,
 292                                              null_nonce(),
 293                                              buf->data[i] + ((offset - buf->offset) << 9),
 294                                              len << 9);
 295
 296                         if (memcmp(stripe_csum(v, i, j), &csum, csum_bytes)) {
 297                                 bch_err_ratelimited(c,
 298                                         "checksum error while doing reconstruct read (%u:%u)",
 299                                         i, j);
 300                                 clear_bit(i, buf->valid);
 301                                 break;
 302                         }
 303
 304                         offset += len;
 305                 }
 306         }
 307 }
 308
 309 /* Erasure coding: */
 310
 311 static void ec_generate_ec(struct ec_stripe_buf *buf)
 312 {
 313         struct bch_stripe *v = &buf->key.v;
 314         unsigned nr_data = v->nr_blocks - v->nr_redundant;
 315         unsigned bytes = le16_to_cpu(v->sectors) << 9;
 316
 317         raid_gen(nr_data, v->nr_redundant, bytes, buf->data);
 318 }
 319
 320 static unsigned ec_nr_failed(struct ec_stripe_buf *buf)
 321 {
 322         return buf->key.v.nr_blocks -
 323                 bitmap_weight(buf->valid, buf->key.v.nr_blocks);
 324 }
 325
 326 static int ec_do_recov(struct bch_fs *c, struct ec_stripe_buf *buf)
 327 {
 328         struct bch_stripe *v = &buf->key.v;
 329         unsigned i, failed[BCH_BKEY_PTRS_MAX], nr_failed = 0;
 330         unsigned nr_data = v->nr_blocks - v->nr_redundant;
 331         unsigned bytes = buf->size << 9;
 332
 333         if (ec_nr_failed(buf) > v->nr_redundant) {
 334                 bch_err_ratelimited(c,
 335                         "error doing reconstruct read: unable to read enough blocks");
 336                 return -1;
 337         }
 338
 339         for (i = 0; i < nr_data; i++)
 340                 if (!test_bit(i, buf->valid))
 341                         failed[nr_failed++] = i;
 342
 343         raid_rec(nr_failed, failed, nr_data, v->nr_redundant, bytes, buf->data);
 344         return 0;
 345 }
 346
 347 /* IO: */
 348
 349 static void ec_block_endio(struct bio *bio)
 350 {
 351         struct ec_bio *ec_bio = container_of(bio, struct ec_bio, bio);
 352         struct bch_dev *ca = ec_bio->ca;
 353         struct closure *cl = bio->bi_private;
 354
 355         if (bch2_dev_io_err_on(bio->bi_status, ca, "erasure coding %s error: %s",
 356                                bio_data_dir(bio) ? "write" : "read",
 357                                bch2_blk_status_to_str(bio->bi_status)))
 358                 clear_bit(ec_bio->idx, ec_bio->buf->valid);
 359
 360         bio_put(&ec_bio->bio);
 361         percpu_ref_put(&ca->io_ref);
 362         closure_put(cl);
 363 }
 364
 365 static void ec_block_io(struct bch_fs *c, struct ec_stripe_buf *buf,
 366                         unsigned rw, unsigned idx, struct closure *cl)
 367 {
 368         struct bch_stripe *v = &buf->key.v;
 369         unsigned offset = 0, bytes = buf->size << 9;
 370         struct bch_extent_ptr *ptr = &v->ptrs[idx];
 371         struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
 372         enum bch_data_type data_type = idx < buf->key.v.nr_blocks - buf->key.v.nr_redundant
 373                 ? BCH_DATA_user
 374                 : BCH_DATA_parity;
 375
 376         if (!bch2_dev_get_ioref(ca, rw)) {
 377                 clear_bit(idx, buf->valid);
 378                 return;
 379         }
 380
 381         this_cpu_add(ca->io_done->sectors[rw][data_type], buf->size);
 382
 383         while (offset < bytes) {
 384                 unsigned nr_iovecs = min_t(size_t, BIO_MAX_PAGES,
 385                                            DIV_ROUND_UP(bytes, PAGE_SIZE));
 386                 unsigned b = min_t(size_t, bytes - offset,
 387                                    nr_iovecs << PAGE_SHIFT);
 388                 struct ec_bio *ec_bio;
 389
 390                 ec_bio = container_of(bio_alloc_bioset(GFP_KERNEL, nr_iovecs,
 391                                                        &c->ec_bioset),
 392                                       struct ec_bio, bio);
 393
 394                 ec_bio->ca                      = ca;
 395                 ec_bio->buf                     = buf;
 396                 ec_bio->idx                     = idx;
 397
 398                 bio_set_dev(&ec_bio->bio, ca->disk_sb.bdev);
 399                 bio_set_op_attrs(&ec_bio->bio, rw, 0);
 400
 401                 ec_bio->bio.bi_iter.bi_sector   = ptr->offset + buf->offset + (offset >> 9);
 402                 ec_bio->bio.bi_end_io           = ec_block_endio;
 403                 ec_bio->bio.bi_private          = cl;
 404
 405                 bch2_bio_map(&ec_bio->bio, buf->data[idx] + offset, b);
 406
 407                 closure_get(cl);
 408                 percpu_ref_get(&ca->io_ref);
 409
 410                 submit_bio(&ec_bio->bio);
 411
 412                 offset += b;
 413         }
 414
 415         percpu_ref_put(&ca->io_ref);
 416 }
 417
 418 /* recovery read path: */
 419 int bch2_ec_read_extent(struct bch_fs *c, struct bch_read_bio *rbio)
 420 {
 421         struct btree_trans trans;
 422         struct btree_iter *iter;
 423         struct ec_stripe_buf *buf;
 424         struct closure cl;
 425         struct bkey_s_c k;
 426         struct bch_stripe *v;
 427         unsigned stripe_idx;
 428         unsigned offset, end;
 429         unsigned i, nr_data, csum_granularity;
 430         int ret = 0, idx;
 431
 432         closure_init_stack(&cl);
 433
 434         BUG_ON(!rbio->pick.has_ec);
 435
 436         stripe_idx = rbio->pick.ec.idx;
 437
 438         buf = kzalloc(sizeof(*buf), GFP_NOIO);
 439         if (!buf)
 440                 return -ENOMEM;
 441
 442         bch2_trans_init(&trans, c, 0, 0);
 443
 444         iter = bch2_trans_get_iter(&trans, BTREE_ID_EC,
 445                                    POS(0, stripe_idx),
 446                                    BTREE_ITER_SLOTS);
 447         k = bch2_btree_iter_peek_slot(iter);
 448         if (bkey_err(k) || k.k->type != KEY_TYPE_stripe) {
 449                 bch_err_ratelimited(c,
 450                         "error doing reconstruct read: stripe not found");
 451                 kfree(buf);
 452                 return bch2_trans_exit(&trans) ?: -EIO;
 453         }
 454
 455         bkey_reassemble(&buf->key.k_i, k);
 456         bch2_trans_exit(&trans);
 457
 458         v = &buf->key.v;
 459
 460         nr_data = v->nr_blocks - v->nr_redundant;
 461
 462         idx = ptr_matches_stripe(c, v, &rbio->pick.ptr);
 463         BUG_ON(idx < 0);
 464
 465         csum_granularity = 1U << v->csum_granularity_bits;
 466
 467         offset  = rbio->bio.bi_iter.bi_sector - v->ptrs[idx].offset;
 468         end     = offset + bio_sectors(&rbio->bio);
 469
 470         BUG_ON(end > le16_to_cpu(v->sectors));
 471
 472         buf->offset     = round_down(offset, csum_granularity);
 473         buf->size       = min_t(unsigned, le16_to_cpu(v->sectors),
 474                                 round_up(end, csum_granularity)) - buf->offset;
 475
 476         for (i = 0; i < v->nr_blocks; i++) {
 477                 buf->data[i] = kmalloc(buf->size << 9, GFP_NOIO);
 478                 if (!buf->data[i]) {
 479                         ret = -ENOMEM;
 480                         goto err;
 481                 }
 482         }
 483
 484         memset(buf->valid, 0xFF, sizeof(buf->valid));
 485
 486         for (i = 0; i < v->nr_blocks; i++) {
 487                 struct bch_extent_ptr *ptr = v->ptrs + i;
 488                 struct bch_dev *ca = bch_dev_bkey_exists(c, ptr->dev);
 489
 490                 if (ptr_stale(ca, ptr)) {
 491                         bch_err_ratelimited(c,
 492                                           "error doing reconstruct read: stale pointer");
 493                         clear_bit(i, buf->valid);
 494                         continue;
 495                 }
 496
 497                 ec_block_io(c, buf, REQ_OP_READ, i, &cl);
 498         }
 499
 500         closure_sync(&cl);
 501
 502         if (ec_nr_failed(buf) > v->nr_redundant) {
 503                 bch_err_ratelimited(c,
 504                         "error doing reconstruct read: unable to read enough blocks");
 505                 ret = -EIO;
 506                 goto err;
 507         }
 508
 509         ec_validate_checksums(c, buf);
 510
 511         ret = ec_do_recov(c, buf);
 512         if (ret)
 513                 goto err;
 514
 515         memcpy_to_bio(&rbio->bio, rbio->bio.bi_iter,
 516                       buf->data[idx] + ((offset - buf->offset) << 9));
 517 err:
 518         for (i = 0; i < v->nr_blocks; i++)
 519                 kfree(buf->data[i]);
 520         kfree(buf);
 521         return ret;
 522 }
 523
 524 /* stripe bucket accounting: */
 525
 526 static int __ec_stripe_mem_alloc(struct bch_fs *c, size_t idx, gfp_t gfp)
 527 {
 528         ec_stripes_heap n, *h = &c->ec_stripes_heap;
 529
 530         if (idx >= h->size) {
 531                 if (!init_heap(&n, max(1024UL, roundup_pow_of_two(idx + 1)), gfp))
 532                         return -ENOMEM;
 533
 534                 spin_lock(&c->ec_stripes_heap_lock);
 535                 if (n.size > h->size) {
 536                         memcpy(n.data, h->data, h->used * sizeof(h->data[0]));
 537                         n.used = h->used;
 538                         swap(*h, n);
 539                 }
 540                 spin_unlock(&c->ec_stripes_heap_lock);
 541
 542                 free_heap(&n);
 543         }
 544
 545         if (!genradix_ptr_alloc(&c->stripes[0], idx, gfp))
 546                 return -ENOMEM;
 547
 548         if (c->gc_pos.phase != GC_PHASE_NOT_RUNNING &&
 549             !genradix_ptr_alloc(&c->stripes[1], idx, gfp))
 550                 return -ENOMEM;
 551
 552         return 0;
 553 }
 554
 555 static int ec_stripe_mem_alloc(struct bch_fs *c,
 556                                struct btree_iter *iter)
 557 {
 558         size_t idx = iter->pos.offset;
 559         int ret = 0;
 560
 561         if (!__ec_stripe_mem_alloc(c, idx, GFP_NOWAIT|__GFP_NOWARN))
 562                 return ret;
 563
 564         bch2_trans_unlock(iter->trans);
 565         ret = -EINTR;
 566
 567         if (!__ec_stripe_mem_alloc(c, idx, GFP_KERNEL))
 568                 return ret;
 569
 570         return -ENOMEM;
 571 }
 572
 573 static ssize_t stripe_idx_to_delete(struct bch_fs *c)
 574 {
 575         ec_stripes_heap *h = &c->ec_stripes_heap;
 576
 577         return h->used && h->data[0].blocks_nonempty == 0
 578                 ? h->data[0].idx : -1;
 579 }
 580
 581 static inline int ec_stripes_heap_cmp(ec_stripes_heap *h,
 582                                       struct ec_stripe_heap_entry l,
 583                                       struct ec_stripe_heap_entry r)
 584 {
 585         return ((l.blocks_nonempty > r.blocks_nonempty) -
 586                 (l.blocks_nonempty < r.blocks_nonempty));
 587 }
 588
 589 static inline void ec_stripes_heap_set_backpointer(ec_stripes_heap *h,
 590                                                    size_t i)
 591 {
 592         struct bch_fs *c = container_of(h, struct bch_fs, ec_stripes_heap);
 593
 594         genradix_ptr(&c->stripes[0], h->data[i].idx)->heap_idx = i;
 595 }
 596
 597 static void heap_verify_backpointer(struct bch_fs *c, size_t idx)
 598 {
 599         ec_stripes_heap *h = &c->ec_stripes_heap;
 600         struct stripe *m = genradix_ptr(&c->stripes[0], idx);
 601
 602         BUG_ON(!m->alive);
 603         BUG_ON(m->heap_idx >= h->used);
 604         BUG_ON(h->data[m->heap_idx].idx != idx);
 605 }
 606
 607 void bch2_stripes_heap_del(struct bch_fs *c,
 608                            struct stripe *m, size_t idx)
 609 {
 610         if (!m->on_heap)
 611                 return;
 612
 613         m->on_heap = false;
 614
 615         heap_verify_backpointer(c, idx);
 616
 617         heap_del(&c->ec_stripes_heap, m->heap_idx,
 618                  ec_stripes_heap_cmp,
 619                  ec_stripes_heap_set_backpointer);
 620 }
 621
 622 void bch2_stripes_heap_insert(struct bch_fs *c,
 623                               struct stripe *m, size_t idx)
 624 {
 625         if (m->on_heap)
 626                 return;
 627
 628         BUG_ON(heap_full(&c->ec_stripes_heap));
 629
 630         m->on_heap = true;
 631
 632         heap_add(&c->ec_stripes_heap, ((struct ec_stripe_heap_entry) {
 633                         .idx = idx,
 634                         .blocks_nonempty = m->blocks_nonempty,
 635                 }),
 636                  ec_stripes_heap_cmp,
 637                  ec_stripes_heap_set_backpointer);
 638
 639         heap_verify_backpointer(c, idx);
 640 }
 641
 642 void bch2_stripes_heap_update(struct bch_fs *c,
 643                               struct stripe *m, size_t idx)
 644 {
 645         ec_stripes_heap *h = &c->ec_stripes_heap;
 646         size_t i;
 647
 648         if (!m->on_heap)
 649                 return;
 650
 651         heap_verify_backpointer(c, idx);
 652
 653         h->data[m->heap_idx].blocks_nonempty = m->blocks_nonempty;
 654
 655         i = m->heap_idx;
 656         heap_sift_up(h,   i, ec_stripes_heap_cmp,
 657                      ec_stripes_heap_set_backpointer);
 658         heap_sift_down(h, i, ec_stripes_heap_cmp,
 659                        ec_stripes_heap_set_backpointer);
 660
 661         heap_verify_backpointer(c, idx);
 662
 663         if (stripe_idx_to_delete(c) >= 0 &&
 664             !percpu_ref_is_dying(&c->writes))
 665                 schedule_work(&c->ec_stripe_delete_work);
 666 }
 667
 668 /* stripe deletion */
 669
 670 static int ec_stripe_delete(struct bch_fs *c, size_t idx)
 671 {
 672         //pr_info("deleting stripe %zu", idx);
 673         return bch2_btree_delete_range(c, BTREE_ID_EC,
 674                                        POS(0, idx),
 675                                        POS(0, idx + 1),
 676                                        NULL);
 677 }
 678
 679 static void ec_stripe_delete_work(struct work_struct *work)
 680 {
 681         struct bch_fs *c =
 682                 container_of(work, struct bch_fs, ec_stripe_delete_work);
 683         ssize_t idx;
 684
 685         while (1) {
 686                 spin_lock(&c->ec_stripes_heap_lock);
 687                 idx = stripe_idx_to_delete(c);
 688                 if (idx < 0) {
 689                         spin_unlock(&c->ec_stripes_heap_lock);
 690                         break;
 691                 }
 692
 693                 bch2_stripes_heap_del(c, genradix_ptr(&c->stripes[0], idx), idx);
 694                 spin_unlock(&c->ec_stripes_heap_lock);
 695
 696                 if (ec_stripe_delete(c, idx))
 697                         break;
 698         }
 699 }
 700
 701 /* stripe creation: */
 702
 703 static int ec_stripe_bkey_insert(struct bch_fs *c,
 704                                  struct ec_stripe_new *s,
 705                                  struct bkey_i_stripe *stripe)
 706 {
 707         struct btree_trans trans;
 708         struct btree_iter *iter;
 709         struct bkey_s_c k;
 710         struct bpos start_pos = POS(0, c->ec_stripe_hint);
 711         int ret;
 712
 713         bch2_trans_init(&trans, c, 0, 0);
 714 retry:
 715         bch2_trans_begin(&trans);
 716
 717         for_each_btree_key(&trans, iter, BTREE_ID_EC, start_pos,
 718                            BTREE_ITER_SLOTS|BTREE_ITER_INTENT, k, ret) {
 719                 if (bkey_cmp(k.k->p, POS(0, U32_MAX)) > 0) {
 720                         if (start_pos.offset) {
 721                                 start_pos = POS_MIN;
 722                                 bch2_btree_iter_set_pos(iter, start_pos);
 723                                 continue;
 724                         }
 725
 726                         ret = -ENOSPC;
 727                         break;
 728                 }
 729
 730                 if (bkey_deleted(k.k))
 731                         goto found_slot;
 732         }
 733
 734         goto err;
 735 found_slot:
 736         start_pos = iter->pos;
 737
 738         ret = ec_stripe_mem_alloc(c, iter);
 739         if (ret)
 740                 goto err;
 741
 742         stripe->k.p = iter->pos;
 743
 744         bch2_trans_update(&trans, iter, &stripe->k_i, 0);
 745
 746         ret = bch2_trans_commit(&trans, &s->res, NULL,
 747                                 BTREE_INSERT_NOFAIL);
 748 err:
 749         bch2_trans_iter_put(&trans, iter);
 750
 751         if (ret == -EINTR)
 752                 goto retry;
 753
 754         c->ec_stripe_hint = ret ? start_pos.offset : start_pos.offset + 1;
 755         bch2_trans_exit(&trans);
 756
 757         return ret;
 758 }
 759
 760 static void extent_stripe_ptr_add(struct bkey_s_extent e,
 761                                   struct ec_stripe_buf *s,
 762                                   struct bch_extent_ptr *ptr,
 763                                   unsigned block)
 764 {
 765         struct bch_extent_stripe_ptr *dst = (void *) ptr;
 766         union bch_extent_entry *end = extent_entry_last(e);
 767
 768         memmove_u64s_up(dst + 1, dst, (u64 *) end - (u64 *) dst);
 769         e.k->u64s += sizeof(*dst) / sizeof(u64);
 770
 771         *dst = (struct bch_extent_stripe_ptr) {
 772                 .type = 1 << BCH_EXTENT_ENTRY_stripe_ptr,
 773                 .block          = block,
 774                 .idx            = s->key.k.p.offset,
 775         };
 776 }
 777
 778 static int ec_stripe_update_ptrs(struct bch_fs *c,
 779                                  struct ec_stripe_buf *s,
 780                                  struct bkey *pos)
 781 {
 782         struct btree_trans trans;
 783         struct btree_iter *iter;
 784         struct bkey_s_c k;
 785         struct bkey_s_extent e;
 786         struct bkey_buf sk;
 787         int ret = 0, dev, idx;
 788
 789         bch2_bkey_buf_init(&sk);
 790         bch2_trans_init(&trans, c, BTREE_ITER_MAX, 0);
 791
 792         /* XXX this doesn't support the reflink btree */
 793
 794         iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS,
 795                                    bkey_start_pos(pos),
 796                                    BTREE_ITER_INTENT);
 797
 798         while ((k = bch2_btree_iter_peek(iter)).k &&
 799                !(ret = bkey_err(k)) &&
 800                bkey_cmp(bkey_start_pos(k.k), pos->p) < 0) {
 801                 struct bch_extent_ptr *ptr, *ec_ptr = NULL;
 802
 803                 if (extent_has_stripe_ptr(k, s->key.k.p.offset)) {
 804                         bch2_btree_iter_next(iter);
 805                         continue;
 806                 }
 807
 808                 idx = extent_matches_stripe(c, &s->key.v, k);
 809                 if (idx < 0) {
 810                         bch2_btree_iter_next(iter);
 811                         continue;
 812                 }
 813
 814                 dev = s->key.v.ptrs[idx].dev;
 815
 816                 bch2_bkey_buf_reassemble(&sk, c, k);
 817                 e = bkey_i_to_s_extent(sk.k);
 818
 819                 bch2_bkey_drop_ptrs(e.s, ptr, ptr->dev != dev);
 820                 ec_ptr = (void *) bch2_bkey_has_device(e.s_c, dev);
 821                 BUG_ON(!ec_ptr);
 822
 823                 extent_stripe_ptr_add(e, s, ec_ptr, idx);
 824
 825                 bch2_btree_iter_set_pos(iter, bkey_start_pos(&sk.k->k));
 826                 bch2_trans_update(&trans, iter, sk.k, 0);
 827
 828                 ret = bch2_trans_commit(&trans, NULL, NULL,
 829                                         BTREE_INSERT_NOFAIL);
 830                 if (ret == -EINTR)
 831                         ret = 0;
 832                 if (ret)
 833                         break;
 834         }
 835
 836         bch2_trans_exit(&trans);
 837         bch2_bkey_buf_exit(&sk, c);
 838
 839         return ret;
 840 }
 841
 842 /*
 843  * data buckets of new stripe all written: create the stripe
 844  */
 845 static void ec_stripe_create(struct ec_stripe_new *s)
 846 {
 847         struct bch_fs *c = s->c;
 848         struct open_bucket *ob;
 849         struct bkey_i *k;
 850         struct stripe *m;
 851         struct bch_stripe *v = &s->new_stripe.key.v;
 852         unsigned i, nr_data = v->nr_blocks - v->nr_redundant;
 853         int ret;
 854
 855         BUG_ON(s->h->s == s);
 856
 857         closure_sync(&s->iodone);
 858
 859         if (s->err) {
 860                 if (s->err != -EROFS)
 861                         bch_err(c, "error creating stripe: error writing data buckets");
 862                 goto err;
 863         }
 864
 865         if (s->have_existing_stripe) {
 866                 ec_validate_checksums(c, &s->existing_stripe);
 867
 868                 if (ec_do_recov(c, &s->existing_stripe)) {
 869                         bch_err(c, "error creating stripe: error reading existing stripe");
 870                         goto err;
 871                 }
 872
 873                 for (i = 0; i < nr_data; i++)
 874                         if (stripe_blockcount_get(&s->existing_stripe.key.v, i))
 875                                 swap(s->new_stripe.data[i],
 876                                      s->existing_stripe.data[i]);
 877
 878                 ec_stripe_buf_free(&s->existing_stripe);
 879         }
 880
 881         BUG_ON(!s->allocated);
 882
 883         if (!percpu_ref_tryget(&c->writes))
 884                 goto err;
 885
 886         BUG_ON(bitmap_weight(s->blocks_allocated,
 887                              s->blocks.nr) != s->blocks.nr);
 888
 889         ec_generate_ec(&s->new_stripe);
 890
 891         ec_generate_checksums(&s->new_stripe);
 892
 893         /* write p/q: */
 894         for (i = nr_data; i < v->nr_blocks; i++)
 895                 ec_block_io(c, &s->new_stripe, REQ_OP_WRITE, i, &s->iodone);
 896         closure_sync(&s->iodone);
 897
 898         if (ec_nr_failed(&s->new_stripe)) {
 899                 bch_err(c, "error creating stripe: error writing redundancy buckets");
 900                 goto err_put_writes;
 901         }
 902
 903         ret = s->have_existing_stripe
 904                 ? bch2_btree_insert(c, BTREE_ID_EC, &s->new_stripe.key.k_i,
 905                                     &s->res, NULL, BTREE_INSERT_NOFAIL)
 906                 : ec_stripe_bkey_insert(c, s, &s->new_stripe.key);
 907         if (ret) {
 908                 bch_err(c, "error creating stripe: error creating stripe key");
 909                 goto err_put_writes;
 910         }
 911
 912         for_each_keylist_key(&s->keys, k) {
 913                 ret = ec_stripe_update_ptrs(c, &s->new_stripe, &k->k);
 914                 if (ret) {
 915                         bch_err(c, "error creating stripe: error %i updating pointers", ret);
 916                         break;
 917                 }
 918         }
 919
 920         spin_lock(&c->ec_stripes_heap_lock);
 921         m = genradix_ptr(&c->stripes[0], s->new_stripe.key.k.p.offset);
 922 #if 0
 923         pr_info("created a %s stripe %llu",
 924                 s->have_existing_stripe ? "existing" : "new",
 925                 s->stripe.key.k.p.offset);
 926 #endif
 927         BUG_ON(m->on_heap);
 928         bch2_stripes_heap_insert(c, m, s->new_stripe.key.k.p.offset);
 929         spin_unlock(&c->ec_stripes_heap_lock);
 930 err_put_writes:
 931         percpu_ref_put(&c->writes);
 932 err:
 933         bch2_disk_reservation_put(c, &s->res);
 934
 935         open_bucket_for_each(c, &s->blocks, ob, i) {
 936                 ob->ec = NULL;
 937                 __bch2_open_bucket_put(c, ob);
 938         }
 939
 940         bch2_open_buckets_put(c, &s->parity);
 941
 942         bch2_keylist_free(&s->keys, s->inline_keys);
 943
 944         ec_stripe_buf_free(&s->existing_stripe);
 945         ec_stripe_buf_free(&s->new_stripe);
 946         closure_debug_destroy(&s->iodone);
 947         kfree(s);
 948 }
 949
 950 static void ec_stripe_create_work(struct work_struct *work)
 951 {
 952         struct bch_fs *c = container_of(work,
 953                 struct bch_fs, ec_stripe_create_work);
 954         struct ec_stripe_new *s, *n;
 955 restart:
 956         mutex_lock(&c->ec_stripe_new_lock);
 957         list_for_each_entry_safe(s, n, &c->ec_stripe_new_list, list)
 958                 if (!atomic_read(&s->pin)) {
 959                         list_del(&s->list);
 960                         mutex_unlock(&c->ec_stripe_new_lock);
 961                         ec_stripe_create(s);
 962                         goto restart;
 963                 }
 964         mutex_unlock(&c->ec_stripe_new_lock);
 965 }
 966
 967 static void ec_stripe_new_put(struct bch_fs *c, struct ec_stripe_new *s)
 968 {
 969         BUG_ON(atomic_read(&s->pin) <= 0);
 970
 971         if (atomic_dec_and_test(&s->pin)) {
 972                 BUG_ON(!s->pending);
 973                 queue_work(system_long_wq, &c->ec_stripe_create_work);
 974         }
 975 }
 976
 977 static void ec_stripe_set_pending(struct bch_fs *c, struct ec_stripe_head *h)
 978 {
 979         struct ec_stripe_new *s = h->s;
 980
 981         BUG_ON(!s->allocated && !s->err);
 982
 983         h->s            = NULL;
 984         s->pending      = true;
 985
 986         mutex_lock(&c->ec_stripe_new_lock);
 987         list_add(&s->list, &c->ec_stripe_new_list);
 988         mutex_unlock(&c->ec_stripe_new_lock);
 989
 990         ec_stripe_new_put(c, s);
 991 }
 992
 993 /* have a full bucket - hand it off to be erasure coded: */
 994 void bch2_ec_bucket_written(struct bch_fs *c, struct open_bucket *ob)
 995 {
 996         struct ec_stripe_new *s = ob->ec;
 997
 998         if (ob->sectors_free)
 999                 s->err = -1;
1000
1001         ec_stripe_new_put(c, s);
1002 }
1003
1004 void bch2_ec_bucket_cancel(struct bch_fs *c, struct open_bucket *ob)
1005 {
1006         struct ec_stripe_new *s = ob->ec;
1007
1008         s->err = -EIO;
1009 }
1010
1011 void *bch2_writepoint_ec_buf(struct bch_fs *c, struct write_point *wp)
1012 {
1013         struct open_bucket *ob = ec_open_bucket(c, &wp->ptrs);
1014         struct bch_dev *ca;
1015         unsigned offset;
1016
1017         if (!ob)
1018                 return NULL;
1019
1020         ca      = bch_dev_bkey_exists(c, ob->ptr.dev);
1021         offset  = ca->mi.bucket_size - ob->sectors_free;
1022
1023         return ob->ec->new_stripe.data[ob->ec_idx] + (offset << 9);
1024 }
1025
1026 void bch2_ec_add_backpointer(struct bch_fs *c, struct write_point *wp,
1027                              struct bpos pos, unsigned sectors)
1028 {
1029         struct open_bucket *ob = ec_open_bucket(c, &wp->ptrs);
1030         struct ec_stripe_new *ec;
1031
1032         if (!ob)
1033                 return;
1034
1035         //pr_info("adding backpointer at %llu:%llu", pos.inode, pos.offset);
1036
1037         ec = ob->ec;
1038         mutex_lock(&ec->lock);
1039
1040         if (bch2_keylist_realloc(&ec->keys, ec->inline_keys,
1041                                  ARRAY_SIZE(ec->inline_keys),
1042                                  BKEY_U64s)) {
1043                 BUG();
1044         }
1045
1046         bkey_init(&ec->keys.top->k);
1047         ec->keys.top->k.p       = pos;
1048         bch2_key_resize(&ec->keys.top->k, sectors);
1049         bch2_keylist_push(&ec->keys);
1050
1051         mutex_unlock(&ec->lock);
1052 }
1053
1054 static int unsigned_cmp(const void *_l, const void *_r)
1055 {
1056         unsigned l = *((const unsigned *) _l);
1057         unsigned r = *((const unsigned *) _r);
1058
1059         return cmp_int(l, r);
1060 }
1061
1062 /* pick most common bucket size: */
1063 static unsigned pick_blocksize(struct bch_fs *c,
1064                                struct bch_devs_mask *devs)
1065 {
1066         struct bch_dev *ca;
1067         unsigned i, nr = 0, sizes[BCH_SB_MEMBERS_MAX];
1068         struct {
1069                 unsigned nr, size;
1070         } cur = { 0, 0 }, best = { 0, 0 };
1071
1072         for_each_member_device_rcu(ca, c, i, devs)
1073                 sizes[nr++] = ca->mi.bucket_size;
1074
1075         sort(sizes, nr, sizeof(unsigned), unsigned_cmp, NULL);
1076
1077         for (i = 0; i < nr; i++) {
1078                 if (sizes[i] != cur.size) {
1079                         if (cur.nr > best.nr)
1080                                 best = cur;
1081
1082                         cur.nr = 0;
1083                         cur.size = sizes[i];
1084                 }
1085
1086                 cur.nr++;
1087         }
1088
1089         if (cur.nr > best.nr)
1090                 best = cur;
1091
1092         return best.size;
1093 }
1094
1095 static bool may_create_new_stripe(struct bch_fs *c)
1096 {
1097         return false;
1098 }
1099
1100 static void ec_stripe_key_init(struct bch_fs *c,
1101                                struct bkey_i_stripe *s,
1102                                unsigned nr_data,
1103                                unsigned nr_parity,
1104                                unsigned stripe_size)
1105 {
1106         unsigned u64s;
1107
1108         bkey_stripe_init(&s->k_i);
1109         s->v.sectors                    = cpu_to_le16(stripe_size);
1110         s->v.algorithm                  = 0;
1111         s->v.nr_blocks                  = nr_data + nr_parity;
1112         s->v.nr_redundant               = nr_parity;
1113         s->v.csum_granularity_bits      = ilog2(c->sb.encoded_extent_max);
1114         s->v.csum_type                  = BCH_CSUM_CRC32C;
1115         s->v.pad                        = 0;
1116
1117         while ((u64s = stripe_val_u64s(&s->v)) > BKEY_VAL_U64s_MAX) {
1118                 BUG_ON(1 << s->v.csum_granularity_bits >=
1119                        le16_to_cpu(s->v.sectors) ||
1120                        s->v.csum_granularity_bits == U8_MAX);
1121                 s->v.csum_granularity_bits++;
1122         }
1123
1124         set_bkey_val_u64s(&s->k, u64s);
1125 }
1126
1127 static int ec_new_stripe_alloc(struct bch_fs *c, struct ec_stripe_head *h)
1128 {
1129         struct ec_stripe_new *s;
1130
1131         lockdep_assert_held(&h->lock);
1132
1133         s = kzalloc(sizeof(*s), GFP_KERNEL);
1134         if (!s)
1135                 return -ENOMEM;
1136
1137         mutex_init(&s->lock);
1138         closure_init(&s->iodone, NULL);
1139         atomic_set(&s->pin, 1);
1140         s->c            = c;
1141         s->h            = h;
1142         s->nr_data      = min_t(unsigned, h->nr_active_devs,
1143                                 BCH_BKEY_PTRS_MAX) - h->redundancy;
1144         s->nr_parity    = h->redundancy;
1145
1146         bch2_keylist_init(&s->keys, s->inline_keys);
1147
1148         s->new_stripe.offset    = 0;
1149         s->new_stripe.size      = h->blocksize;
1150
1151         ec_stripe_key_init(c, &s->new_stripe.key, s->nr_data,
1152                            s->nr_parity, h->blocksize);
1153
1154         h->s = s;
1155         return 0;
1156 }
1157
1158 static struct ec_stripe_head *
1159 ec_new_stripe_head_alloc(struct bch_fs *c, unsigned target,
1160                          unsigned algo, unsigned redundancy,
1161                          bool copygc)
1162 {
1163         struct ec_stripe_head *h;
1164         struct bch_dev *ca;
1165         unsigned i;
1166
1167         h = kzalloc(sizeof(*h), GFP_KERNEL);
1168         if (!h)
1169                 return NULL;
1170
1171         mutex_init(&h->lock);
1172         mutex_lock(&h->lock);
1173
1174         h->target       = target;
1175         h->algo         = algo;
1176         h->redundancy   = redundancy;
1177         h->copygc       = copygc;
1178
1179         rcu_read_lock();
1180         h->devs = target_rw_devs(c, BCH_DATA_user, target);
1181
1182         for_each_member_device_rcu(ca, c, i, &h->devs)
1183                 if (!ca->mi.durability)
1184                         __clear_bit(i, h->devs.d);
1185
1186         h->blocksize = pick_blocksize(c, &h->devs);
1187
1188         for_each_member_device_rcu(ca, c, i, &h->devs)
1189                 if (ca->mi.bucket_size == h->blocksize)
1190                         h->nr_active_devs++;
1191
1192         rcu_read_unlock();
1193         list_add(&h->list, &c->ec_stripe_head_list);
1194         return h;
1195 }
1196
1197 void bch2_ec_stripe_head_put(struct bch_fs *c, struct ec_stripe_head *h)
1198 {
1199         if (h->s &&
1200             h->s->allocated &&
1201             bitmap_weight(h->s->blocks_allocated,
1202                           h->s->blocks.nr) == h->s->blocks.nr)
1203                 ec_stripe_set_pending(c, h);
1204
1205         mutex_unlock(&h->lock);
1206 }
1207
1208 struct ec_stripe_head *__bch2_ec_stripe_head_get(struct bch_fs *c,
1209                                                  unsigned target,
1210                                                  unsigned algo,
1211                                                  unsigned redundancy,
1212                                                  bool copygc)
1213 {
1214         struct ec_stripe_head *h;
1215
1216         if (!redundancy)
1217                 return NULL;
1218
1219         mutex_lock(&c->ec_stripe_head_lock);
1220         list_for_each_entry(h, &c->ec_stripe_head_list, list)
1221                 if (h->target           == target &&
1222                     h->algo             == algo &&
1223                     h->redundancy       == redundancy &&
1224                     h->copygc           == copygc) {
1225                         mutex_lock(&h->lock);
1226                         goto found;
1227                 }
1228
1229         h = ec_new_stripe_head_alloc(c, target, algo, redundancy, copygc);
1230 found:
1231         mutex_unlock(&c->ec_stripe_head_lock);
1232         return h;
1233 }
1234
1235 static enum bucket_alloc_ret
1236 new_stripe_alloc_buckets(struct bch_fs *c, struct ec_stripe_head *h,
1237                          struct closure *cl)
1238 {
1239         struct bch_devs_mask devs;
1240         struct open_bucket *ob;
1241         unsigned i, nr_have, nr_data =
1242                 min_t(unsigned, h->nr_active_devs,
1243                       BCH_BKEY_PTRS_MAX) - h->redundancy;
1244         bool have_cache = true;
1245         enum bucket_alloc_ret ret = ALLOC_SUCCESS;
1246
1247         devs = h->devs;
1248
1249         for_each_set_bit(i, h->s->blocks_allocated, BCH_BKEY_PTRS_MAX) {
1250                 __clear_bit(h->s->new_stripe.key.v.ptrs[i].dev, devs.d);
1251                 --nr_data;
1252         }
1253
1254         BUG_ON(h->s->blocks.nr > nr_data);
1255         BUG_ON(h->s->parity.nr > h->redundancy);
1256
1257         open_bucket_for_each(c, &h->s->parity, ob, i)
1258                 __clear_bit(ob->ptr.dev, devs.d);
1259         open_bucket_for_each(c, &h->s->blocks, ob, i)
1260                 __clear_bit(ob->ptr.dev, devs.d);
1261
1262         percpu_down_read(&c->mark_lock);
1263         rcu_read_lock();
1264
1265         if (h->s->parity.nr < h->redundancy) {
1266                 nr_have = h->s->parity.nr;
1267
1268                 ret = bch2_bucket_alloc_set(c, &h->s->parity,
1269                                             &h->parity_stripe,
1270                                             &devs,
1271                                             h->redundancy,
1272                                             &nr_have,
1273                                             &have_cache,
1274                                             h->copygc
1275                                             ? RESERVE_MOVINGGC
1276                                             : RESERVE_NONE,
1277                                             0,
1278                                             cl);
1279                 if (ret)
1280                         goto err;
1281         }
1282
1283         if (h->s->blocks.nr < nr_data) {
1284                 nr_have = h->s->blocks.nr;
1285
1286                 ret = bch2_bucket_alloc_set(c, &h->s->blocks,
1287                                             &h->block_stripe,
1288                                             &devs,
1289                                             nr_data,
1290                                             &nr_have,
1291                                             &have_cache,
1292                                             h->copygc
1293                                             ? RESERVE_MOVINGGC
1294                                             : RESERVE_NONE,
1295                                             0,
1296                                             cl);
1297                 if (ret)
1298                         goto err;
1299         }
1300 err:
1301         rcu_read_unlock();
1302         percpu_up_read(&c->mark_lock);
1303         return ret;
1304 }
1305
1306 /* XXX: doesn't obey target: */
1307 static s64 get_existing_stripe(struct bch_fs *c,
1308                                unsigned target,
1309                                unsigned algo,
1310                                unsigned redundancy)
1311 {
1312         ec_stripes_heap *h = &c->ec_stripes_heap;
1313         struct stripe *m;
1314         size_t heap_idx;
1315         u64 stripe_idx;
1316
1317         if (may_create_new_stripe(c))
1318                 return -1;
1319
1320         spin_lock(&c->ec_stripes_heap_lock);
1321         for (heap_idx = 0; heap_idx < h->used; heap_idx++) {
1322                 if (!h->data[heap_idx].blocks_nonempty)
1323                         continue;
1324
1325                 stripe_idx = h->data[heap_idx].idx;
1326                 m = genradix_ptr(&c->stripes[0], stripe_idx);
1327
1328                 if (m->algorithm        == algo &&
1329                     m->nr_redundant     == redundancy &&
1330                     m->blocks_nonempty  < m->nr_blocks - m->nr_redundant) {
1331                         bch2_stripes_heap_del(c, m, stripe_idx);
1332                         spin_unlock(&c->ec_stripes_heap_lock);
1333                         return stripe_idx;
1334                 }
1335         }
1336
1337         spin_unlock(&c->ec_stripes_heap_lock);
1338         return -1;
1339 }
1340
1341 static int get_stripe_key(struct bch_fs *c, u64 idx, struct ec_stripe_buf *stripe)
1342 {
1343         struct btree_trans trans;
1344         struct btree_iter *iter;
1345         struct bkey_s_c k;
1346         int ret;
1347
1348         bch2_trans_init(&trans, c, 0, 0);
1349         iter = bch2_trans_get_iter(&trans, BTREE_ID_EC, POS(0, idx), BTREE_ITER_SLOTS);
1350         k = bch2_btree_iter_peek_slot(iter);
1351         ret = bkey_err(k);
1352         if (!ret)
1353                 bkey_reassemble(&stripe->key.k_i, k);
1354         bch2_trans_exit(&trans);
1355
1356         return ret;
1357 }
1358
1359 struct ec_stripe_head *bch2_ec_stripe_head_get(struct bch_fs *c,
1360                                                unsigned target,
1361                                                unsigned algo,
1362                                                unsigned redundancy,
1363                                                bool copygc,
1364                                                struct closure *cl)
1365 {
1366         struct ec_stripe_head *h;
1367         struct open_bucket *ob;
1368         unsigned i, data_idx = 0;
1369         s64 idx;
1370         int ret;
1371
1372         h = __bch2_ec_stripe_head_get(c, target, algo, redundancy, copygc);
1373         if (!h) {
1374                 bch_err(c, "no stripe head");
1375                 return NULL;
1376         }
1377
1378         if (!h->s) {
1379                 if (ec_new_stripe_alloc(c, h)) {
1380                         bch2_ec_stripe_head_put(c, h);
1381                         bch_err(c, "failed to allocate new stripe");
1382                         return NULL;
1383                 }
1384
1385                 idx = get_existing_stripe(c, target, algo, redundancy);
1386                 if (idx >= 0) {
1387                         h->s->have_existing_stripe = true;
1388                         ret = get_stripe_key(c, idx, &h->s->existing_stripe);
1389                         if (ret) {
1390                                 bch2_fs_fatal_error(c, "error reading stripe key: %i", ret);
1391                                 bch2_ec_stripe_head_put(c, h);
1392                                 return NULL;
1393                         }
1394
1395                         if (ec_stripe_buf_alloc(&h->s->existing_stripe)) {
1396                                 /*
1397                                  * this is a problem: we have deleted from the
1398                                  * stripes heap already
1399                                  */
1400                                 BUG();
1401                         }
1402
1403                         for (i = 0; i < h->s->existing_stripe.key.v.nr_blocks; i++) {
1404                                 if (stripe_blockcount_get(&h->s->existing_stripe.key.v, i))
1405                                         __set_bit(i, h->s->blocks_allocated);
1406
1407                                 ec_block_io(c, &h->s->existing_stripe, READ, i, &h->s->iodone);
1408                         }
1409
1410                         bkey_copy(&h->s->new_stripe.key.k_i,
1411                                   &h->s->existing_stripe.key.k_i);
1412                 }
1413
1414                 if (ec_stripe_buf_alloc(&h->s->new_stripe)) {
1415                         BUG();
1416                 }
1417         }
1418
1419         if (!h->s->allocated) {
1420                 if (!h->s->have_existing_stripe &&
1421                     !h->s->res.sectors) {
1422                         ret = bch2_disk_reservation_get(c, &h->s->res,
1423                                         h->blocksize,
1424                                         h->s->nr_parity, 0);
1425                         if (ret) {
1426                                 /*
1427                                  * This means we need to wait for copygc to
1428                                  * empty out buckets from existing stripes:
1429                                  */
1430                                 bch2_ec_stripe_head_put(c, h);
1431                                 h = NULL;
1432                                 goto out;
1433                         }
1434                 }
1435
1436                 ret = new_stripe_alloc_buckets(c, h, cl);
1437                 if (ret) {
1438                         bch2_ec_stripe_head_put(c, h);
1439                         h = ERR_PTR(-ret);
1440                         goto out;
1441                 }
1442
1443                 open_bucket_for_each(c, &h->s->blocks, ob, i) {
1444                         data_idx = find_next_zero_bit(h->s->blocks_allocated,
1445                                                       h->s->nr_data, data_idx);
1446                         BUG_ON(data_idx >= h->s->nr_data);
1447
1448                         h->s->new_stripe.key.v.ptrs[data_idx] = ob->ptr;
1449                         h->s->data_block_idx[i] = data_idx;
1450                         data_idx++;
1451                 }
1452
1453                 open_bucket_for_each(c, &h->s->parity, ob, i)
1454                         h->s->new_stripe.key.v.ptrs[h->s->nr_data + i] = ob->ptr;
1455
1456                 //pr_info("new stripe, blocks_allocated %lx", h->s->blocks_allocated[0]);
1457                 h->s->allocated = true;
1458         }
1459 out:
1460         return h;
1461 }
1462
1463 void bch2_ec_stop_dev(struct bch_fs *c, struct bch_dev *ca)
1464 {
1465         struct ec_stripe_head *h;
1466         struct open_bucket *ob;
1467         unsigned i;
1468
1469         mutex_lock(&c->ec_stripe_head_lock);
1470         list_for_each_entry(h, &c->ec_stripe_head_list, list) {
1471
1472                 mutex_lock(&h->lock);
1473                 if (!h->s)
1474                         goto unlock;
1475
1476                 open_bucket_for_each(c, &h->s->blocks, ob, i)
1477                         if (ob->ptr.dev == ca->dev_idx)
1478                                 goto found;
1479                 open_bucket_for_each(c, &h->s->parity, ob, i)
1480                         if (ob->ptr.dev == ca->dev_idx)
1481                                 goto found;
1482                 goto unlock;
1483 found:
1484                 h->s->err = -EROFS;
1485                 ec_stripe_set_pending(c, h);
1486 unlock:
1487                 mutex_unlock(&h->lock);
1488         }
1489         mutex_unlock(&c->ec_stripe_head_lock);
1490 }
1491
1492 static int __bch2_stripe_write_key(struct btree_trans *trans,
1493                                    struct btree_iter *iter,
1494                                    struct stripe *m,
1495                                    size_t idx,
1496                                    struct bkey_i_stripe *new_key)
1497 {
1498         struct bch_fs *c = trans->c;
1499         struct bkey_s_c k;
1500         unsigned i;
1501         int ret;
1502
1503         bch2_btree_iter_set_pos(iter, POS(0, idx));
1504
1505         k = bch2_btree_iter_peek_slot(iter);
1506         ret = bkey_err(k);
1507         if (ret)
1508                 return ret;
1509
1510         if (k.k->type != KEY_TYPE_stripe)
1511                 return -EIO;
1512
1513         bkey_reassemble(&new_key->k_i, k);
1514
1515         spin_lock(&c->ec_stripes_heap_lock);
1516
1517         for (i = 0; i < new_key->v.nr_blocks; i++)
1518                 stripe_blockcount_set(&new_key->v, i,
1519                                       m->block_sectors[i]);
1520         m->dirty = false;
1521
1522         spin_unlock(&c->ec_stripes_heap_lock);
1523
1524         bch2_trans_update(trans, iter, &new_key->k_i, 0);
1525         return 0;
1526 }
1527
1528 int bch2_stripes_write(struct bch_fs *c, unsigned flags)
1529 {
1530         struct btree_trans trans;
1531         struct btree_iter *iter;
1532         struct genradix_iter giter;
1533         struct bkey_i_stripe *new_key;
1534         struct stripe *m;
1535         int ret = 0;
1536
1537         new_key = kmalloc(255 * sizeof(u64), GFP_KERNEL);
1538         BUG_ON(!new_key);
1539
1540         bch2_trans_init(&trans, c, 0, 0);
1541
1542         iter = bch2_trans_get_iter(&trans, BTREE_ID_EC, POS_MIN,
1543                                    BTREE_ITER_SLOTS|BTREE_ITER_INTENT);
1544
1545         genradix_for_each(&c->stripes[0], giter, m) {
1546                 if (!m->dirty)
1547                         continue;
1548
1549                 ret = __bch2_trans_do(&trans, NULL, NULL,
1550                                       BTREE_INSERT_NOFAIL|flags,
1551                         __bch2_stripe_write_key(&trans, iter, m,
1552                                         giter.pos, new_key));
1553
1554                 if (ret)
1555                         break;
1556         }
1557
1558         bch2_trans_exit(&trans);
1559
1560         kfree(new_key);
1561
1562         return ret;
1563 }
1564
1565 static int bch2_stripes_read_fn(struct bch_fs *c, enum btree_id id,
1566                               unsigned level, struct bkey_s_c k)
1567 {
1568         int ret = 0;
1569
1570         if (k.k->type == KEY_TYPE_stripe) {
1571                 struct stripe *m;
1572
1573                 ret = __ec_stripe_mem_alloc(c, k.k->p.offset, GFP_KERNEL) ?:
1574                         bch2_mark_key(c, k, 0, 0, NULL, 0,
1575                                       BTREE_TRIGGER_NOATOMIC);
1576                 if (ret)
1577                         return ret;
1578
1579                 spin_lock(&c->ec_stripes_heap_lock);
1580                 m = genradix_ptr(&c->stripes[0], k.k->p.offset);
1581                 bch2_stripes_heap_insert(c, m, k.k->p.offset);
1582                 spin_unlock(&c->ec_stripes_heap_lock);
1583         }
1584
1585         return ret;
1586 }
1587
1588 int bch2_stripes_read(struct bch_fs *c, struct journal_keys *journal_keys)
1589 {
1590         int ret = bch2_btree_and_journal_walk(c, journal_keys, BTREE_ID_EC,
1591                                           NULL, bch2_stripes_read_fn);
1592         if (ret)
1593                 bch_err(c, "error reading stripes: %i", ret);
1594
1595         return ret;
1596 }
1597
1598 int bch2_ec_mem_alloc(struct bch_fs *c, bool gc)
1599 {
1600         struct btree_trans trans;
1601         struct btree_iter *iter;
1602         struct bkey_s_c k;
1603         size_t i, idx = 0;
1604         int ret = 0;
1605
1606         bch2_trans_init(&trans, c, 0, 0);
1607
1608         iter = bch2_trans_get_iter(&trans, BTREE_ID_EC, POS(0, U64_MAX), 0);
1609
1610         k = bch2_btree_iter_prev(iter);
1611         if (!IS_ERR_OR_NULL(k.k))
1612                 idx = k.k->p.offset + 1;
1613         ret = bch2_trans_exit(&trans);
1614         if (ret)
1615                 return ret;
1616
1617         if (!idx)
1618                 return 0;
1619
1620         if (!gc &&
1621             !init_heap(&c->ec_stripes_heap, roundup_pow_of_two(idx),
1622                        GFP_KERNEL))
1623                 return -ENOMEM;
1624 #if 0
1625         ret = genradix_prealloc(&c->stripes[gc], idx, GFP_KERNEL);
1626 #else
1627         for (i = 0; i < idx; i++)
1628                 if (!genradix_ptr_alloc(&c->stripes[gc], i, GFP_KERNEL))
1629                         return -ENOMEM;
1630 #endif
1631         return 0;
1632 }
1633
1634 void bch2_stripes_heap_to_text(struct printbuf *out, struct bch_fs *c)
1635 {
1636         ec_stripes_heap *h = &c->ec_stripes_heap;
1637         struct stripe *m;
1638         size_t i;
1639
1640         spin_lock(&c->ec_stripes_heap_lock);
1641         for (i = 0; i < min_t(size_t, h->used, 20); i++) {
1642                 m = genradix_ptr(&c->stripes[0], h->data[i].idx);
1643
1644                 pr_buf(out, "%zu %u/%u+%u\n", h->data[i].idx,
1645                        h->data[i].blocks_nonempty,
1646                        m->nr_blocks - m->nr_redundant,
1647                        m->nr_redundant);
1648         }
1649         spin_unlock(&c->ec_stripes_heap_lock);
1650 }
1651
1652 void bch2_new_stripes_to_text(struct printbuf *out, struct bch_fs *c)
1653 {
1654         struct ec_stripe_head *h;
1655         struct ec_stripe_new *s;
1656
1657         mutex_lock(&c->ec_stripe_head_lock);
1658         list_for_each_entry(h, &c->ec_stripe_head_list, list) {
1659                 pr_buf(out, "target %u algo %u redundancy %u:\n",
1660                        h->target, h->algo, h->redundancy);
1661
1662                 if (h->s)
1663                         pr_buf(out, "\tpending: blocks %u allocated %u\n",
1664                                h->s->blocks.nr,
1665                                bitmap_weight(h->s->blocks_allocated,
1666                                              h->s->blocks.nr));
1667         }
1668         mutex_unlock(&c->ec_stripe_head_lock);
1669
1670         mutex_lock(&c->ec_stripe_new_lock);
1671         list_for_each_entry(s, &c->ec_stripe_new_list, list) {
1672                 pr_buf(out, "\tin flight: blocks %u allocated %u pin %u\n",
1673                        s->blocks.nr,
1674                        bitmap_weight(s->blocks_allocated,
1675                                      s->blocks.nr),
1676                        atomic_read(&s->pin));
1677         }
1678         mutex_unlock(&c->ec_stripe_new_lock);
1679 }
1680
1681 void bch2_fs_ec_exit(struct bch_fs *c)
1682 {
1683         struct ec_stripe_head *h;
1684
1685         while (1) {
1686                 mutex_lock(&c->ec_stripe_head_lock);
1687                 h = list_first_entry_or_null(&c->ec_stripe_head_list,
1688                                              struct ec_stripe_head, list);
1689                 if (h)
1690                         list_del(&h->list);
1691                 mutex_unlock(&c->ec_stripe_head_lock);
1692                 if (!h)
1693                         break;
1694
1695                 BUG_ON(h->s);
1696                 kfree(h);
1697         }
1698
1699         BUG_ON(!list_empty(&c->ec_stripe_new_list));
1700
1701         free_heap(&c->ec_stripes_heap);
1702         genradix_free(&c->stripes[0]);
1703         bioset_exit(&c->ec_bioset);
1704 }
1705
1706 int bch2_fs_ec_init(struct bch_fs *c)
1707 {
1708         INIT_WORK(&c->ec_stripe_create_work, ec_stripe_create_work);
1709         INIT_WORK(&c->ec_stripe_delete_work, ec_stripe_delete_work);
1710
1711         return bioset_init(&c->ec_bioset, 1, offsetof(struct ec_bio, bio),
1712                            BIOSET_NEED_BVECS);
1713 }