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

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include "bcachefs.h"
   4 #include "btree_key_cache.h"
   5 #include "btree_write_buffer.h"
   6 #include "bkey_methods.h"
   7 #include "btree_update.h"
   8 #include "buckets.h"
   9 #include "compress.h"
  10 #include "dirent.h"
  11 #include "error.h"
  12 #include "extents.h"
  13 #include "extent_update.h"
  14 #include "inode.h"
  15 #include "str_hash.h"
  16 #include "snapshot.h"
  17 #include "subvolume.h"
  18 #include "varint.h"
  19
  20 #include <linux/random.h>
  21
  22 #include <asm/unaligned.h>
  23
  24 #define x(name, ...)    #name,
  25 const char * const bch2_inode_opts[] = {
  26         BCH_INODE_OPTS()
  27         NULL,
  28 };
  29
  30 static const char * const bch2_inode_flag_strs[] = {
  31         BCH_INODE_FLAGS()
  32         NULL
  33 };
  34 #undef  x
  35
  36 static const u8 byte_table[8] = { 1, 2, 3, 4, 6, 8, 10, 13 };
  37
  38 static int inode_decode_field(const u8 *in, const u8 *end,
  39                               u64 out[2], unsigned *out_bits)
  40 {
  41         __be64 be[2] = { 0, 0 };
  42         unsigned bytes, shift;
  43         u8 *p;
  44
  45         if (in >= end)
  46                 return -1;
  47
  48         if (!*in)
  49                 return -1;
  50
  51         /*
  52          * position of highest set bit indicates number of bytes:
  53          * shift = number of bits to remove in high byte:
  54          */
  55         shift   = 8 - __fls(*in); /* 1 <= shift <= 8 */
  56         bytes   = byte_table[shift - 1];
  57
  58         if (in + bytes > end)
  59                 return -1;
  60
  61         p = (u8 *) be + 16 - bytes;
  62         memcpy(p, in, bytes);
  63         *p ^= (1 << 8) >> shift;
  64
  65         out[0] = be64_to_cpu(be[0]);
  66         out[1] = be64_to_cpu(be[1]);
  67         *out_bits = out[0] ? 64 + fls64(out[0]) : fls64(out[1]);
  68
  69         return bytes;
  70 }
  71
  72 static inline void bch2_inode_pack_inlined(struct bkey_inode_buf *packed,
  73                                            const struct bch_inode_unpacked *inode)
  74 {
  75         struct bkey_i_inode_v3 *k = &packed->inode;
  76         u8 *out = k->v.fields;
  77         u8 *end = (void *) &packed[1];
  78         u8 *last_nonzero_field = out;
  79         unsigned nr_fields = 0, last_nonzero_fieldnr = 0;
  80         unsigned bytes;
  81         int ret;
  82
  83         bkey_inode_v3_init(&packed->inode.k_i);
  84         packed->inode.k.p.offset        = inode->bi_inum;
  85         packed->inode.v.bi_journal_seq  = cpu_to_le64(inode->bi_journal_seq);
  86         packed->inode.v.bi_hash_seed    = inode->bi_hash_seed;
  87         packed->inode.v.bi_flags        = cpu_to_le64(inode->bi_flags);
  88         packed->inode.v.bi_sectors      = cpu_to_le64(inode->bi_sectors);
  89         packed->inode.v.bi_size         = cpu_to_le64(inode->bi_size);
  90         packed->inode.v.bi_version      = cpu_to_le64(inode->bi_version);
  91         SET_INODEv3_MODE(&packed->inode.v, inode->bi_mode);
  92         SET_INODEv3_FIELDS_START(&packed->inode.v, INODEv3_FIELDS_START_CUR);
  93
  94
  95 #define x(_name, _bits)                                                 \
  96         nr_fields++;                                                    \
  97                                                                         \
  98         if (inode->_name) {                                             \
  99                 ret = bch2_varint_encode_fast(out, inode->_name);       \
 100                 out += ret;                                             \
 101                                                                         \
 102                 if (_bits > 64)                                         \
 103                         *out++ = 0;                                     \
 104                                                                         \
 105                 last_nonzero_field = out;                               \
 106                 last_nonzero_fieldnr = nr_fields;                       \
 107         } else {                                                        \
 108                 *out++ = 0;                                             \
 109                                                                         \
 110                 if (_bits > 64)                                         \
 111                         *out++ = 0;                                     \
 112         }
 113
 114         BCH_INODE_FIELDS_v3()
 115 #undef  x
 116         BUG_ON(out > end);
 117
 118         out = last_nonzero_field;
 119         nr_fields = last_nonzero_fieldnr;
 120
 121         bytes = out - (u8 *) &packed->inode.v;
 122         set_bkey_val_bytes(&packed->inode.k, bytes);
 123         memset_u64s_tail(&packed->inode.v, 0, bytes);
 124
 125         SET_INODEv3_NR_FIELDS(&k->v, nr_fields);
 126
 127         if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG)) {
 128                 struct bch_inode_unpacked unpacked;
 129
 130                 ret = bch2_inode_unpack(bkey_i_to_s_c(&packed->inode.k_i), &unpacked);
 131                 BUG_ON(ret);
 132                 BUG_ON(unpacked.bi_inum         != inode->bi_inum);
 133                 BUG_ON(unpacked.bi_hash_seed    != inode->bi_hash_seed);
 134                 BUG_ON(unpacked.bi_sectors      != inode->bi_sectors);
 135                 BUG_ON(unpacked.bi_size         != inode->bi_size);
 136                 BUG_ON(unpacked.bi_version      != inode->bi_version);
 137                 BUG_ON(unpacked.bi_mode         != inode->bi_mode);
 138
 139 #define x(_name, _bits) if (unpacked._name != inode->_name)             \
 140                         panic("unpacked %llu should be %llu",           \
 141                               (u64) unpacked._name, (u64) inode->_name);
 142                 BCH_INODE_FIELDS_v3()
 143 #undef  x
 144         }
 145 }
 146
 147 void bch2_inode_pack(struct bkey_inode_buf *packed,
 148                      const struct bch_inode_unpacked *inode)
 149 {
 150         bch2_inode_pack_inlined(packed, inode);
 151 }
 152
 153 static noinline int bch2_inode_unpack_v1(struct bkey_s_c_inode inode,
 154                                 struct bch_inode_unpacked *unpacked)
 155 {
 156         const u8 *in = inode.v->fields;
 157         const u8 *end = bkey_val_end(inode);
 158         u64 field[2];
 159         unsigned fieldnr = 0, field_bits;
 160         int ret;
 161
 162 #define x(_name, _bits)                                 \
 163         if (fieldnr++ == INODE_NR_FIELDS(inode.v)) {                    \
 164                 unsigned offset = offsetof(struct bch_inode_unpacked, _name);\
 165                 memset((void *) unpacked + offset, 0,                   \
 166                        sizeof(*unpacked) - offset);                     \
 167                 return 0;                                               \
 168         }                                                               \
 169                                                                         \
 170         ret = inode_decode_field(in, end, field, &field_bits);          \
 171         if (ret < 0)                                                    \
 172                 return ret;                                             \
 173                                                                         \
 174         if (field_bits > sizeof(unpacked->_name) * 8)                   \
 175                 return -1;                                              \
 176                                                                         \
 177         unpacked->_name = field[1];                                     \
 178         in += ret;
 179
 180         BCH_INODE_FIELDS_v2()
 181 #undef  x
 182
 183         /* XXX: signal if there were more fields than expected? */
 184         return 0;
 185 }
 186
 187 static int bch2_inode_unpack_v2(struct bch_inode_unpacked *unpacked,
 188                                 const u8 *in, const u8 *end,
 189                                 unsigned nr_fields)
 190 {
 191         unsigned fieldnr = 0;
 192         int ret;
 193         u64 v[2];
 194
 195 #define x(_name, _bits)                                                 \
 196         if (fieldnr < nr_fields) {                                      \
 197                 ret = bch2_varint_decode_fast(in, end, &v[0]);          \
 198                 if (ret < 0)                                            \
 199                         return ret;                                     \
 200                 in += ret;                                              \
 201                                                                         \
 202                 if (_bits > 64) {                                       \
 203                         ret = bch2_varint_decode_fast(in, end, &v[1]);  \
 204                         if (ret < 0)                                    \
 205                                 return ret;                             \
 206                         in += ret;                                      \
 207                 } else {                                                \
 208                         v[1] = 0;                                       \
 209                 }                                                       \
 210         } else {                                                        \
 211                 v[0] = v[1] = 0;                                        \
 212         }                                                               \
 213                                                                         \
 214         unpacked->_name = v[0];                                         \
 215         if (v[1] || v[0] != unpacked->_name)                            \
 216                 return -1;                                              \
 217         fieldnr++;
 218
 219         BCH_INODE_FIELDS_v2()
 220 #undef  x
 221
 222         /* XXX: signal if there were more fields than expected? */
 223         return 0;
 224 }
 225
 226 static int bch2_inode_unpack_v3(struct bkey_s_c k,
 227                                 struct bch_inode_unpacked *unpacked)
 228 {
 229         struct bkey_s_c_inode_v3 inode = bkey_s_c_to_inode_v3(k);
 230         const u8 *in = inode.v->fields;
 231         const u8 *end = bkey_val_end(inode);
 232         unsigned nr_fields = INODEv3_NR_FIELDS(inode.v);
 233         unsigned fieldnr = 0;
 234         int ret;
 235         u64 v[2];
 236
 237         unpacked->bi_inum       = inode.k->p.offset;
 238         unpacked->bi_journal_seq= le64_to_cpu(inode.v->bi_journal_seq);
 239         unpacked->bi_hash_seed  = inode.v->bi_hash_seed;
 240         unpacked->bi_flags      = le64_to_cpu(inode.v->bi_flags);
 241         unpacked->bi_sectors    = le64_to_cpu(inode.v->bi_sectors);
 242         unpacked->bi_size       = le64_to_cpu(inode.v->bi_size);
 243         unpacked->bi_version    = le64_to_cpu(inode.v->bi_version);
 244         unpacked->bi_mode       = INODEv3_MODE(inode.v);
 245
 246 #define x(_name, _bits)                                                 \
 247         if (fieldnr < nr_fields) {                                      \
 248                 ret = bch2_varint_decode_fast(in, end, &v[0]);          \
 249                 if (ret < 0)                                            \
 250                         return ret;                                     \
 251                 in += ret;                                              \
 252                                                                         \
 253                 if (_bits > 64) {                                       \
 254                         ret = bch2_varint_decode_fast(in, end, &v[1]);  \
 255                         if (ret < 0)                                    \
 256                                 return ret;                             \
 257                         in += ret;                                      \
 258                 } else {                                                \
 259                         v[1] = 0;                                       \
 260                 }                                                       \
 261         } else {                                                        \
 262                 v[0] = v[1] = 0;                                        \
 263         }                                                               \
 264                                                                         \
 265         unpacked->_name = v[0];                                         \
 266         if (v[1] || v[0] != unpacked->_name)                            \
 267                 return -1;                                              \
 268         fieldnr++;
 269
 270         BCH_INODE_FIELDS_v3()
 271 #undef  x
 272
 273         /* XXX: signal if there were more fields than expected? */
 274         return 0;
 275 }
 276
 277 static noinline int bch2_inode_unpack_slowpath(struct bkey_s_c k,
 278                                                struct bch_inode_unpacked *unpacked)
 279 {
 280         memset(unpacked, 0, sizeof(*unpacked));
 281
 282         switch (k.k->type) {
 283         case KEY_TYPE_inode: {
 284                 struct bkey_s_c_inode inode = bkey_s_c_to_inode(k);
 285
 286                 unpacked->bi_inum       = inode.k->p.offset;
 287                 unpacked->bi_journal_seq= 0;
 288                 unpacked->bi_hash_seed  = inode.v->bi_hash_seed;
 289                 unpacked->bi_flags      = le32_to_cpu(inode.v->bi_flags);
 290                 unpacked->bi_mode       = le16_to_cpu(inode.v->bi_mode);
 291
 292                 if (INODE_NEW_VARINT(inode.v)) {
 293                         return bch2_inode_unpack_v2(unpacked, inode.v->fields,
 294                                                     bkey_val_end(inode),
 295                                                     INODE_NR_FIELDS(inode.v));
 296                 } else {
 297                         return bch2_inode_unpack_v1(inode, unpacked);
 298                 }
 299                 break;
 300         }
 301         case KEY_TYPE_inode_v2: {
 302                 struct bkey_s_c_inode_v2 inode = bkey_s_c_to_inode_v2(k);
 303
 304                 unpacked->bi_inum       = inode.k->p.offset;
 305                 unpacked->bi_journal_seq= le64_to_cpu(inode.v->bi_journal_seq);
 306                 unpacked->bi_hash_seed  = inode.v->bi_hash_seed;
 307                 unpacked->bi_flags      = le64_to_cpu(inode.v->bi_flags);
 308                 unpacked->bi_mode       = le16_to_cpu(inode.v->bi_mode);
 309
 310                 return bch2_inode_unpack_v2(unpacked, inode.v->fields,
 311                                             bkey_val_end(inode),
 312                                             INODEv2_NR_FIELDS(inode.v));
 313         }
 314         default:
 315                 BUG();
 316         }
 317 }
 318
 319 int bch2_inode_unpack(struct bkey_s_c k,
 320                       struct bch_inode_unpacked *unpacked)
 321 {
 322         if (likely(k.k->type == KEY_TYPE_inode_v3))
 323                 return bch2_inode_unpack_v3(k, unpacked);
 324         return bch2_inode_unpack_slowpath(k, unpacked);
 325 }
 326
 327 int bch2_inode_peek_nowarn(struct btree_trans *trans,
 328                     struct btree_iter *iter,
 329                     struct bch_inode_unpacked *inode,
 330                     subvol_inum inum, unsigned flags)
 331 {
 332         struct bkey_s_c k;
 333         u32 snapshot;
 334         int ret;
 335
 336         ret = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot);
 337         if (ret)
 338                 return ret;
 339
 340         k = bch2_bkey_get_iter(trans, iter, BTREE_ID_inodes,
 341                                SPOS(0, inum.inum, snapshot),
 342                                flags|BTREE_ITER_CACHED);
 343         ret = bkey_err(k);
 344         if (ret)
 345                 return ret;
 346
 347         ret = bkey_is_inode(k.k) ? 0 : -BCH_ERR_ENOENT_inode;
 348         if (ret)
 349                 goto err;
 350
 351         ret = bch2_inode_unpack(k, inode);
 352         if (ret)
 353                 goto err;
 354
 355         return 0;
 356 err:
 357         bch2_trans_iter_exit(trans, iter);
 358         return ret;
 359 }
 360
 361 int bch2_inode_peek(struct btree_trans *trans,
 362                     struct btree_iter *iter,
 363                     struct bch_inode_unpacked *inode,
 364                     subvol_inum inum, unsigned flags)
 365 {
 366         int ret = bch2_inode_peek_nowarn(trans, iter, inode, inum, flags);
 367         bch_err_msg(trans->c, ret, "looking up inum %u:%llu:", inum.subvol, inum.inum);
 368         return ret;
 369 }
 370
 371 int bch2_inode_write_flags(struct btree_trans *trans,
 372                      struct btree_iter *iter,
 373                      struct bch_inode_unpacked *inode,
 374                      enum btree_update_flags flags)
 375 {
 376         struct bkey_inode_buf *inode_p;
 377
 378         inode_p = bch2_trans_kmalloc(trans, sizeof(*inode_p));
 379         if (IS_ERR(inode_p))
 380                 return PTR_ERR(inode_p);
 381
 382         bch2_inode_pack_inlined(inode_p, inode);
 383         inode_p->inode.k.p.snapshot = iter->snapshot;
 384         return bch2_trans_update(trans, iter, &inode_p->inode.k_i, flags);
 385 }
 386
 387 int __bch2_fsck_write_inode(struct btree_trans *trans,
 388                          struct bch_inode_unpacked *inode,
 389                          u32 snapshot)
 390 {
 391         struct bkey_inode_buf *inode_p =
 392                 bch2_trans_kmalloc(trans, sizeof(*inode_p));
 393
 394         if (IS_ERR(inode_p))
 395                 return PTR_ERR(inode_p);
 396
 397         bch2_inode_pack(inode_p, inode);
 398         inode_p->inode.k.p.snapshot = snapshot;
 399
 400         return bch2_btree_insert_nonextent(trans, BTREE_ID_inodes,
 401                                 &inode_p->inode.k_i,
 402                                 BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE);
 403 }
 404
 405 int bch2_fsck_write_inode(struct btree_trans *trans,
 406                             struct bch_inode_unpacked *inode,
 407                             u32 snapshot)
 408 {
 409         int ret = commit_do(trans, NULL, NULL, BCH_TRANS_COMMIT_no_enospc,
 410                             __bch2_fsck_write_inode(trans, inode, snapshot));
 411         bch_err_fn(trans->c, ret);
 412         return ret;
 413 }
 414
 415 struct bkey_i *bch2_inode_to_v3(struct btree_trans *trans, struct bkey_i *k)
 416 {
 417         struct bch_inode_unpacked u;
 418         struct bkey_inode_buf *inode_p;
 419         int ret;
 420
 421         if (!bkey_is_inode(&k->k))
 422                 return ERR_PTR(-ENOENT);
 423
 424         inode_p = bch2_trans_kmalloc(trans, sizeof(*inode_p));
 425         if (IS_ERR(inode_p))
 426                 return ERR_CAST(inode_p);
 427
 428         ret = bch2_inode_unpack(bkey_i_to_s_c(k), &u);
 429         if (ret)
 430                 return ERR_PTR(ret);
 431
 432         bch2_inode_pack(inode_p, &u);
 433         return &inode_p->inode.k_i;
 434 }
 435
 436 static int __bch2_inode_invalid(struct bch_fs *c, struct bkey_s_c k, struct printbuf *err)
 437 {
 438         struct bch_inode_unpacked unpacked;
 439         int ret = 0;
 440
 441         bkey_fsck_err_on(k.k->p.inode, c, err,
 442                          inode_pos_inode_nonzero,
 443                          "nonzero k.p.inode");
 444
 445         bkey_fsck_err_on(k.k->p.offset < BLOCKDEV_INODE_MAX, c, err,
 446                          inode_pos_blockdev_range,
 447                          "fs inode in blockdev range");
 448
 449         bkey_fsck_err_on(bch2_inode_unpack(k, &unpacked), c, err,
 450                          inode_unpack_error,
 451                          "invalid variable length fields");
 452
 453         bkey_fsck_err_on(unpacked.bi_data_checksum >= BCH_CSUM_OPT_NR + 1, c, err,
 454                          inode_checksum_type_invalid,
 455                          "invalid data checksum type (%u >= %u",
 456                          unpacked.bi_data_checksum, BCH_CSUM_OPT_NR + 1);
 457
 458         bkey_fsck_err_on(unpacked.bi_compression &&
 459                          !bch2_compression_opt_valid(unpacked.bi_compression - 1), c, err,
 460                          inode_compression_type_invalid,
 461                          "invalid compression opt %u", unpacked.bi_compression - 1);
 462
 463         bkey_fsck_err_on((unpacked.bi_flags & BCH_INODE_unlinked) &&
 464                          unpacked.bi_nlink != 0, c, err,
 465                          inode_unlinked_but_nlink_nonzero,
 466                          "flagged as unlinked but bi_nlink != 0");
 467
 468         bkey_fsck_err_on(unpacked.bi_subvol && !S_ISDIR(unpacked.bi_mode), c, err,
 469                          inode_subvol_root_but_not_dir,
 470                          "subvolume root but not a directory");
 471 fsck_err:
 472         return ret;
 473 }
 474
 475 int bch2_inode_invalid(struct bch_fs *c, struct bkey_s_c k,
 476                        enum bkey_invalid_flags flags,
 477                        struct printbuf *err)
 478 {
 479         struct bkey_s_c_inode inode = bkey_s_c_to_inode(k);
 480         int ret = 0;
 481
 482         bkey_fsck_err_on(INODE_STR_HASH(inode.v) >= BCH_STR_HASH_NR, c, err,
 483                          inode_str_hash_invalid,
 484                          "invalid str hash type (%llu >= %u)",
 485                          INODE_STR_HASH(inode.v), BCH_STR_HASH_NR);
 486
 487         ret = __bch2_inode_invalid(c, k, err);
 488 fsck_err:
 489         return ret;
 490 }
 491
 492 int bch2_inode_v2_invalid(struct bch_fs *c, struct bkey_s_c k,
 493                           enum bkey_invalid_flags flags,
 494                           struct printbuf *err)
 495 {
 496         struct bkey_s_c_inode_v2 inode = bkey_s_c_to_inode_v2(k);
 497         int ret = 0;
 498
 499         bkey_fsck_err_on(INODEv2_STR_HASH(inode.v) >= BCH_STR_HASH_NR, c, err,
 500                          inode_str_hash_invalid,
 501                          "invalid str hash type (%llu >= %u)",
 502                          INODEv2_STR_HASH(inode.v), BCH_STR_HASH_NR);
 503
 504         ret = __bch2_inode_invalid(c, k, err);
 505 fsck_err:
 506         return ret;
 507 }
 508
 509 int bch2_inode_v3_invalid(struct bch_fs *c, struct bkey_s_c k,
 510                           enum bkey_invalid_flags flags,
 511                           struct printbuf *err)
 512 {
 513         struct bkey_s_c_inode_v3 inode = bkey_s_c_to_inode_v3(k);
 514         int ret = 0;
 515
 516         bkey_fsck_err_on(INODEv3_FIELDS_START(inode.v) < INODEv3_FIELDS_START_INITIAL ||
 517                          INODEv3_FIELDS_START(inode.v) > bkey_val_u64s(inode.k), c, err,
 518                          inode_v3_fields_start_bad,
 519                          "invalid fields_start (got %llu, min %u max %zu)",
 520                          INODEv3_FIELDS_START(inode.v),
 521                          INODEv3_FIELDS_START_INITIAL,
 522                          bkey_val_u64s(inode.k));
 523
 524         bkey_fsck_err_on(INODEv3_STR_HASH(inode.v) >= BCH_STR_HASH_NR, c, err,
 525                          inode_str_hash_invalid,
 526                          "invalid str hash type (%llu >= %u)",
 527                          INODEv3_STR_HASH(inode.v), BCH_STR_HASH_NR);
 528
 529         ret = __bch2_inode_invalid(c, k, err);
 530 fsck_err:
 531         return ret;
 532 }
 533
 534 static void __bch2_inode_unpacked_to_text(struct printbuf *out,
 535                                           struct bch_inode_unpacked *inode)
 536 {
 537         printbuf_indent_add(out, 2);
 538         prt_printf(out, "mode=%o", inode->bi_mode);
 539         prt_newline(out);
 540
 541         prt_str(out, "flags=");
 542         prt_bitflags(out, bch2_inode_flag_strs, inode->bi_flags & ((1U << 20) - 1));
 543         prt_printf(out, " (%x)", inode->bi_flags);
 544         prt_newline(out);
 545
 546         prt_printf(out, "journal_seq=%llu", inode->bi_journal_seq);
 547         prt_newline(out);
 548
 549         prt_printf(out, "bi_size=%llu", inode->bi_size);
 550         prt_newline(out);
 551
 552         prt_printf(out, "bi_sectors=%llu", inode->bi_sectors);
 553         prt_newline(out);
 554
 555         prt_newline(out);
 556         prt_printf(out, "bi_version=%llu", inode->bi_version);
 557
 558 #define x(_name, _bits)                                         \
 559         prt_printf(out, #_name "=%llu", (u64) inode->_name);    \
 560         prt_newline(out);
 561         BCH_INODE_FIELDS_v3()
 562 #undef  x
 563         printbuf_indent_sub(out, 2);
 564 }
 565
 566 void bch2_inode_unpacked_to_text(struct printbuf *out, struct bch_inode_unpacked *inode)
 567 {
 568         prt_printf(out, "inum: %llu ", inode->bi_inum);
 569         __bch2_inode_unpacked_to_text(out, inode);
 570 }
 571
 572 void bch2_inode_to_text(struct printbuf *out, struct bch_fs *c, struct bkey_s_c k)
 573 {
 574         struct bch_inode_unpacked inode;
 575
 576         if (bch2_inode_unpack(k, &inode)) {
 577                 prt_printf(out, "(unpack error)");
 578                 return;
 579         }
 580
 581         __bch2_inode_unpacked_to_text(out, &inode);
 582 }
 583
 584 static inline u64 bkey_inode_flags(struct bkey_s_c k)
 585 {
 586         switch (k.k->type) {
 587         case KEY_TYPE_inode:
 588                 return le32_to_cpu(bkey_s_c_to_inode(k).v->bi_flags);
 589         case KEY_TYPE_inode_v2:
 590                 return le64_to_cpu(bkey_s_c_to_inode_v2(k).v->bi_flags);
 591         case KEY_TYPE_inode_v3:
 592                 return le64_to_cpu(bkey_s_c_to_inode_v3(k).v->bi_flags);
 593         default:
 594                 return 0;
 595         }
 596 }
 597
 598 static inline bool bkey_is_deleted_inode(struct bkey_s_c k)
 599 {
 600         return bkey_inode_flags(k) & BCH_INODE_unlinked;
 601 }
 602
 603 int bch2_trigger_inode(struct btree_trans *trans,
 604                        enum btree_id btree_id, unsigned level,
 605                        struct bkey_s_c old,
 606                        struct bkey_s new,
 607                        unsigned flags)
 608 {
 609         s64 nr = bkey_is_inode(new.k) - bkey_is_inode(old.k);
 610
 611         if (flags & BTREE_TRIGGER_TRANSACTIONAL) {
 612                 if (nr) {
 613                         int ret = bch2_replicas_deltas_realloc(trans, 0);
 614                         if (ret)
 615                                 return ret;
 616
 617                         trans->fs_usage_deltas->nr_inodes += nr;
 618                 }
 619
 620                 bool old_deleted = bkey_is_deleted_inode(old);
 621                 bool new_deleted = bkey_is_deleted_inode(new.s_c);
 622                 if (old_deleted != new_deleted) {
 623                         int ret = bch2_btree_bit_mod_buffered(trans, BTREE_ID_deleted_inodes,
 624                                                               new.k->p, new_deleted);
 625                         if (ret)
 626                                 return ret;
 627                 }
 628         }
 629
 630         if ((flags & BTREE_TRIGGER_ATOMIC) && (flags & BTREE_TRIGGER_INSERT)) {
 631                 BUG_ON(!trans->journal_res.seq);
 632
 633                 bkey_s_to_inode_v3(new).v->bi_journal_seq = cpu_to_le64(trans->journal_res.seq);
 634         }
 635
 636         if (flags & BTREE_TRIGGER_GC) {
 637                 struct bch_fs *c = trans->c;
 638
 639                 percpu_down_read(&c->mark_lock);
 640                 this_cpu_add(c->usage_gc->b.nr_inodes, nr);
 641                 percpu_up_read(&c->mark_lock);
 642         }
 643
 644         return 0;
 645 }
 646
 647 int bch2_inode_generation_invalid(struct bch_fs *c, struct bkey_s_c k,
 648                                   enum bkey_invalid_flags flags,
 649                                   struct printbuf *err)
 650 {
 651         int ret = 0;
 652
 653         bkey_fsck_err_on(k.k->p.inode, c, err,
 654                          inode_pos_inode_nonzero,
 655                          "nonzero k.p.inode");
 656 fsck_err:
 657         return ret;
 658 }
 659
 660 void bch2_inode_generation_to_text(struct printbuf *out, struct bch_fs *c,
 661                                    struct bkey_s_c k)
 662 {
 663         struct bkey_s_c_inode_generation gen = bkey_s_c_to_inode_generation(k);
 664
 665         prt_printf(out, "generation: %u", le32_to_cpu(gen.v->bi_generation));
 666 }
 667
 668 void bch2_inode_init_early(struct bch_fs *c,
 669                            struct bch_inode_unpacked *inode_u)
 670 {
 671         enum bch_str_hash_type str_hash =
 672                 bch2_str_hash_opt_to_type(c, c->opts.str_hash);
 673
 674         memset(inode_u, 0, sizeof(*inode_u));
 675
 676         /* ick */
 677         inode_u->bi_flags |= str_hash << INODE_STR_HASH_OFFSET;
 678         get_random_bytes(&inode_u->bi_hash_seed,
 679                          sizeof(inode_u->bi_hash_seed));
 680 }
 681
 682 void bch2_inode_init_late(struct bch_inode_unpacked *inode_u, u64 now,
 683                           uid_t uid, gid_t gid, umode_t mode, dev_t rdev,
 684                           struct bch_inode_unpacked *parent)
 685 {
 686         inode_u->bi_mode        = mode;
 687         inode_u->bi_uid         = uid;
 688         inode_u->bi_gid         = gid;
 689         inode_u->bi_dev         = rdev;
 690         inode_u->bi_atime       = now;
 691         inode_u->bi_mtime       = now;
 692         inode_u->bi_ctime       = now;
 693         inode_u->bi_otime       = now;
 694
 695         if (parent && parent->bi_mode & S_ISGID) {
 696                 inode_u->bi_gid = parent->bi_gid;
 697                 if (S_ISDIR(mode))
 698                         inode_u->bi_mode |= S_ISGID;
 699         }
 700
 701         if (parent) {
 702 #define x(_name, ...)   inode_u->bi_##_name = parent->bi_##_name;
 703                 BCH_INODE_OPTS()
 704 #undef x
 705         }
 706 }
 707
 708 void bch2_inode_init(struct bch_fs *c, struct bch_inode_unpacked *inode_u,
 709                      uid_t uid, gid_t gid, umode_t mode, dev_t rdev,
 710                      struct bch_inode_unpacked *parent)
 711 {
 712         bch2_inode_init_early(c, inode_u);
 713         bch2_inode_init_late(inode_u, bch2_current_time(c),
 714                              uid, gid, mode, rdev, parent);
 715 }
 716
 717 static inline u32 bkey_generation(struct bkey_s_c k)
 718 {
 719         switch (k.k->type) {
 720         case KEY_TYPE_inode:
 721         case KEY_TYPE_inode_v2:
 722                 BUG();
 723         case KEY_TYPE_inode_generation:
 724                 return le32_to_cpu(bkey_s_c_to_inode_generation(k).v->bi_generation);
 725         default:
 726                 return 0;
 727         }
 728 }
 729
 730 /*
 731  * This just finds an empty slot:
 732  */
 733 int bch2_inode_create(struct btree_trans *trans,
 734                       struct btree_iter *iter,
 735                       struct bch_inode_unpacked *inode_u,
 736                       u32 snapshot, u64 cpu)
 737 {
 738         struct bch_fs *c = trans->c;
 739         struct bkey_s_c k;
 740         u64 min, max, start, pos, *hint;
 741         int ret = 0;
 742         unsigned bits = (c->opts.inodes_32bit ? 31 : 63);
 743
 744         if (c->opts.shard_inode_numbers) {
 745                 bits -= c->inode_shard_bits;
 746
 747                 min = (cpu << bits);
 748                 max = (cpu << bits) | ~(ULLONG_MAX << bits);
 749
 750                 min = max_t(u64, min, BLOCKDEV_INODE_MAX);
 751                 hint = c->unused_inode_hints + cpu;
 752         } else {
 753                 min = BLOCKDEV_INODE_MAX;
 754                 max = ~(ULLONG_MAX << bits);
 755                 hint = c->unused_inode_hints;
 756         }
 757
 758         start = READ_ONCE(*hint);
 759
 760         if (start >= max || start < min)
 761                 start = min;
 762
 763         pos = start;
 764         bch2_trans_iter_init(trans, iter, BTREE_ID_inodes, POS(0, pos),
 765                              BTREE_ITER_ALL_SNAPSHOTS|
 766                              BTREE_ITER_INTENT);
 767 again:
 768         while ((k = bch2_btree_iter_peek(iter)).k &&
 769                !(ret = bkey_err(k)) &&
 770                bkey_lt(k.k->p, POS(0, max))) {
 771                 if (pos < iter->pos.offset)
 772                         goto found_slot;
 773
 774                 /*
 775                  * We don't need to iterate over keys in every snapshot once
 776                  * we've found just one:
 777                  */
 778                 pos = iter->pos.offset + 1;
 779                 bch2_btree_iter_set_pos(iter, POS(0, pos));
 780         }
 781
 782         if (!ret && pos < max)
 783                 goto found_slot;
 784
 785         if (!ret && start == min)
 786                 ret = -BCH_ERR_ENOSPC_inode_create;
 787
 788         if (ret) {
 789                 bch2_trans_iter_exit(trans, iter);
 790                 return ret;
 791         }
 792
 793         /* Retry from start */
 794         pos = start = min;
 795         bch2_btree_iter_set_pos(iter, POS(0, pos));
 796         goto again;
 797 found_slot:
 798         bch2_btree_iter_set_pos(iter, SPOS(0, pos, snapshot));
 799         k = bch2_btree_iter_peek_slot(iter);
 800         ret = bkey_err(k);
 801         if (ret) {
 802                 bch2_trans_iter_exit(trans, iter);
 803                 return ret;
 804         }
 805
 806         *hint                   = k.k->p.offset;
 807         inode_u->bi_inum        = k.k->p.offset;
 808         inode_u->bi_generation  = bkey_generation(k);
 809         return 0;
 810 }
 811
 812 static int bch2_inode_delete_keys(struct btree_trans *trans,
 813                                   subvol_inum inum, enum btree_id id)
 814 {
 815         struct btree_iter iter;
 816         struct bkey_s_c k;
 817         struct bkey_i delete;
 818         struct bpos end = POS(inum.inum, U64_MAX);
 819         u32 snapshot;
 820         int ret = 0;
 821
 822         /*
 823          * We're never going to be deleting partial extents, no need to use an
 824          * extent iterator:
 825          */
 826         bch2_trans_iter_init(trans, &iter, id, POS(inum.inum, 0),
 827                              BTREE_ITER_INTENT);
 828
 829         while (1) {
 830                 bch2_trans_begin(trans);
 831
 832                 ret = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot);
 833                 if (ret)
 834                         goto err;
 835
 836                 bch2_btree_iter_set_snapshot(&iter, snapshot);
 837
 838                 k = bch2_btree_iter_peek_upto(&iter, end);
 839                 ret = bkey_err(k);
 840                 if (ret)
 841                         goto err;
 842
 843                 if (!k.k)
 844                         break;
 845
 846                 bkey_init(&delete.k);
 847                 delete.k.p = iter.pos;
 848
 849                 if (iter.flags & BTREE_ITER_IS_EXTENTS)
 850                         bch2_key_resize(&delete.k,
 851                                         bpos_min(end, k.k->p).offset -
 852                                         iter.pos.offset);
 853
 854                 ret = bch2_trans_update(trans, &iter, &delete, 0) ?:
 855                       bch2_trans_commit(trans, NULL, NULL,
 856                                         BCH_TRANS_COMMIT_no_enospc);
 857 err:
 858                 if (ret && !bch2_err_matches(ret, BCH_ERR_transaction_restart))
 859                         break;
 860         }
 861
 862         bch2_trans_iter_exit(trans, &iter);
 863         return ret;
 864 }
 865
 866 int bch2_inode_rm(struct bch_fs *c, subvol_inum inum)
 867 {
 868         struct btree_trans *trans = bch2_trans_get(c);
 869         struct btree_iter iter = { NULL };
 870         struct bkey_i_inode_generation delete;
 871         struct bch_inode_unpacked inode_u;
 872         struct bkey_s_c k;
 873         u32 snapshot;
 874         int ret;
 875
 876         /*
 877          * If this was a directory, there shouldn't be any real dirents left -
 878          * but there could be whiteouts (from hash collisions) that we should
 879          * delete:
 880          *
 881          * XXX: the dirent could ideally would delete whiteouts when they're no
 882          * longer needed
 883          */
 884         ret   = bch2_inode_delete_keys(trans, inum, BTREE_ID_extents) ?:
 885                 bch2_inode_delete_keys(trans, inum, BTREE_ID_xattrs) ?:
 886                 bch2_inode_delete_keys(trans, inum, BTREE_ID_dirents);
 887         if (ret)
 888                 goto err;
 889 retry:
 890         bch2_trans_begin(trans);
 891
 892         ret = bch2_subvolume_get_snapshot(trans, inum.subvol, &snapshot);
 893         if (ret)
 894                 goto err;
 895
 896         k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_inodes,
 897                                SPOS(0, inum.inum, snapshot),
 898                                BTREE_ITER_INTENT|BTREE_ITER_CACHED);
 899         ret = bkey_err(k);
 900         if (ret)
 901                 goto err;
 902
 903         if (!bkey_is_inode(k.k)) {
 904                 bch2_fs_inconsistent(c,
 905                                      "inode %llu:%u not found when deleting",
 906                                      inum.inum, snapshot);
 907                 ret = -EIO;
 908                 goto err;
 909         }
 910
 911         bch2_inode_unpack(k, &inode_u);
 912
 913         bkey_inode_generation_init(&delete.k_i);
 914         delete.k.p = iter.pos;
 915         delete.v.bi_generation = cpu_to_le32(inode_u.bi_generation + 1);
 916
 917         ret   = bch2_trans_update(trans, &iter, &delete.k_i, 0) ?:
 918                 bch2_trans_commit(trans, NULL, NULL,
 919                                 BCH_TRANS_COMMIT_no_enospc);
 920 err:
 921         bch2_trans_iter_exit(trans, &iter);
 922         if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
 923                 goto retry;
 924
 925         bch2_trans_put(trans);
 926         return ret;
 927 }
 928
 929 int bch2_inode_find_by_inum_nowarn_trans(struct btree_trans *trans,
 930                                   subvol_inum inum,
 931                                   struct bch_inode_unpacked *inode)
 932 {
 933         struct btree_iter iter;
 934         int ret;
 935
 936         ret = bch2_inode_peek_nowarn(trans, &iter, inode, inum, 0);
 937         if (!ret)
 938                 bch2_trans_iter_exit(trans, &iter);
 939         return ret;
 940 }
 941
 942 int bch2_inode_find_by_inum_trans(struct btree_trans *trans,
 943                                   subvol_inum inum,
 944                                   struct bch_inode_unpacked *inode)
 945 {
 946         struct btree_iter iter;
 947         int ret;
 948
 949         ret = bch2_inode_peek(trans, &iter, inode, inum, 0);
 950         if (!ret)
 951                 bch2_trans_iter_exit(trans, &iter);
 952         return ret;
 953 }
 954
 955 int bch2_inode_find_by_inum(struct bch_fs *c, subvol_inum inum,
 956                             struct bch_inode_unpacked *inode)
 957 {
 958         return bch2_trans_do(c, NULL, NULL, 0,
 959                 bch2_inode_find_by_inum_trans(trans, inum, inode));
 960 }
 961
 962 int bch2_inode_nlink_inc(struct bch_inode_unpacked *bi)
 963 {
 964         if (bi->bi_flags & BCH_INODE_unlinked)
 965                 bi->bi_flags &= ~BCH_INODE_unlinked;
 966         else {
 967                 if (bi->bi_nlink == U32_MAX)
 968                         return -EINVAL;
 969
 970                 bi->bi_nlink++;
 971         }
 972
 973         return 0;
 974 }
 975
 976 void bch2_inode_nlink_dec(struct btree_trans *trans, struct bch_inode_unpacked *bi)
 977 {
 978         if (bi->bi_nlink && (bi->bi_flags & BCH_INODE_unlinked)) {
 979                 bch2_trans_inconsistent(trans, "inode %llu unlinked but link count nonzero",
 980                                         bi->bi_inum);
 981                 return;
 982         }
 983
 984         if (bi->bi_flags & BCH_INODE_unlinked) {
 985                 bch2_trans_inconsistent(trans, "inode %llu link count underflow", bi->bi_inum);
 986                 return;
 987         }
 988
 989         if (bi->bi_nlink)
 990                 bi->bi_nlink--;
 991         else
 992                 bi->bi_flags |= BCH_INODE_unlinked;
 993 }
 994
 995 struct bch_opts bch2_inode_opts_to_opts(struct bch_inode_unpacked *inode)
 996 {
 997         struct bch_opts ret = { 0 };
 998 #define x(_name, _bits)                                                 \
 999         if (inode->bi_##_name)                                          \
1000                 opt_set(ret, _name, inode->bi_##_name - 1);
1001         BCH_INODE_OPTS()
1002 #undef x
1003         return ret;
1004 }
1005
1006 void bch2_inode_opts_get(struct bch_io_opts *opts, struct bch_fs *c,
1007                          struct bch_inode_unpacked *inode)
1008 {
1009 #define x(_name, _bits)         opts->_name = inode_opt_get(c, inode, _name);
1010         BCH_INODE_OPTS()
1011 #undef x
1012
1013         if (opts->nocow)
1014                 opts->compression = opts->background_compression = opts->data_checksum = opts->erasure_code = 0;
1015 }
1016
1017 int bch2_inum_opts_get(struct btree_trans *trans, subvol_inum inum, struct bch_io_opts *opts)
1018 {
1019         struct bch_inode_unpacked inode;
1020         int ret = lockrestart_do(trans, bch2_inode_find_by_inum_trans(trans, inum, &inode));
1021
1022         if (ret)
1023                 return ret;
1024
1025         bch2_inode_opts_get(opts, trans->c, &inode);
1026         return 0;
1027 }
1028
1029 int bch2_inode_rm_snapshot(struct btree_trans *trans, u64 inum, u32 snapshot)
1030 {
1031         struct bch_fs *c = trans->c;
1032         struct btree_iter iter = { NULL };
1033         struct bkey_i_inode_generation delete;
1034         struct bch_inode_unpacked inode_u;
1035         struct bkey_s_c k;
1036         int ret;
1037
1038         do {
1039                 ret   = bch2_btree_delete_range_trans(trans, BTREE_ID_extents,
1040                                                       SPOS(inum, 0, snapshot),
1041                                                       SPOS(inum, U64_MAX, snapshot),
1042                                                       0, NULL) ?:
1043                         bch2_btree_delete_range_trans(trans, BTREE_ID_dirents,
1044                                                       SPOS(inum, 0, snapshot),
1045                                                       SPOS(inum, U64_MAX, snapshot),
1046                                                       0, NULL) ?:
1047                         bch2_btree_delete_range_trans(trans, BTREE_ID_xattrs,
1048                                                       SPOS(inum, 0, snapshot),
1049                                                       SPOS(inum, U64_MAX, snapshot),
1050                                                       0, NULL);
1051         } while (ret == -BCH_ERR_transaction_restart_nested);
1052         if (ret)
1053                 goto err;
1054 retry:
1055         bch2_trans_begin(trans);
1056
1057         k = bch2_bkey_get_iter(trans, &iter, BTREE_ID_inodes,
1058                                SPOS(0, inum, snapshot), BTREE_ITER_INTENT);
1059         ret = bkey_err(k);
1060         if (ret)
1061                 goto err;
1062
1063         if (!bkey_is_inode(k.k)) {
1064                 bch2_fs_inconsistent(c,
1065                                      "inode %llu:%u not found when deleting",
1066                                      inum, snapshot);
1067                 ret = -EIO;
1068                 goto err;
1069         }
1070
1071         bch2_inode_unpack(k, &inode_u);
1072
1073         /* Subvolume root? */
1074         if (inode_u.bi_subvol)
1075                 bch_warn(c, "deleting inode %llu marked as unlinked, but also a subvolume root!?", inode_u.bi_inum);
1076
1077         bkey_inode_generation_init(&delete.k_i);
1078         delete.k.p = iter.pos;
1079         delete.v.bi_generation = cpu_to_le32(inode_u.bi_generation + 1);
1080
1081         ret   = bch2_trans_update(trans, &iter, &delete.k_i, 0) ?:
1082                 bch2_trans_commit(trans, NULL, NULL,
1083                                 BCH_TRANS_COMMIT_no_enospc);
1084 err:
1085         bch2_trans_iter_exit(trans, &iter);
1086         if (bch2_err_matches(ret, BCH_ERR_transaction_restart))
1087                 goto retry;
1088
1089         return ret ?: -BCH_ERR_transaction_restart_nested;
1090 }
1091
1092 static int may_delete_deleted_inode(struct btree_trans *trans,
1093                                     struct btree_iter *iter,
1094                                     struct bpos pos,
1095                                     bool *need_another_pass)
1096 {
1097         struct bch_fs *c = trans->c;
1098         struct btree_iter inode_iter;
1099         struct bkey_s_c k;
1100         struct bch_inode_unpacked inode;
1101         int ret;
1102
1103         k = bch2_bkey_get_iter(trans, &inode_iter, BTREE_ID_inodes, pos, BTREE_ITER_CACHED);
1104         ret = bkey_err(k);
1105         if (ret)
1106                 return ret;
1107
1108         ret = bkey_is_inode(k.k) ? 0 : -BCH_ERR_ENOENT_inode;
1109         if (fsck_err_on(!bkey_is_inode(k.k), c,
1110                         deleted_inode_missing,
1111                         "nonexistent inode %llu:%u in deleted_inodes btree",
1112                         pos.offset, pos.snapshot))
1113                 goto delete;
1114
1115         ret = bch2_inode_unpack(k, &inode);
1116         if (ret)
1117                 goto out;
1118
1119         if (S_ISDIR(inode.bi_mode)) {
1120                 ret = bch2_empty_dir_snapshot(trans, pos.offset, 0, pos.snapshot);
1121                 if (fsck_err_on(bch2_err_matches(ret, ENOTEMPTY),
1122                                 c, deleted_inode_is_dir,
1123                                 "non empty directory %llu:%u in deleted_inodes btree",
1124                                 pos.offset, pos.snapshot))
1125                         goto delete;
1126                 if (ret)
1127                         goto out;
1128         }
1129
1130         if (fsck_err_on(!(inode.bi_flags & BCH_INODE_unlinked), c,
1131                         deleted_inode_not_unlinked,
1132                         "non-deleted inode %llu:%u in deleted_inodes btree",
1133                         pos.offset, pos.snapshot))
1134                 goto delete;
1135
1136         if (c->sb.clean &&
1137             !fsck_err(c,
1138                       deleted_inode_but_clean,
1139                       "filesystem marked as clean but have deleted inode %llu:%u",
1140                       pos.offset, pos.snapshot)) {
1141                 ret = 0;
1142                 goto out;
1143         }
1144
1145         if (bch2_snapshot_is_internal_node(c, pos.snapshot)) {
1146                 struct bpos new_min_pos;
1147
1148                 ret = bch2_propagate_key_to_snapshot_leaves(trans, inode_iter.btree_id, k, &new_min_pos);
1149                 if (ret)
1150                         goto out;
1151
1152                 inode.bi_flags &= ~BCH_INODE_unlinked;
1153
1154                 ret = bch2_inode_write_flags(trans, &inode_iter, &inode,
1155                                              BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE);
1156                 bch_err_msg(c, ret, "clearing inode unlinked flag");
1157                 if (ret)
1158                         goto out;
1159
1160                 /*
1161                  * We'll need another write buffer flush to pick up the new
1162                  * unlinked inodes in the snapshot leaves:
1163                  */
1164                 *need_another_pass = true;
1165                 goto out;
1166         }
1167
1168         ret = 1;
1169 out:
1170 fsck_err:
1171         bch2_trans_iter_exit(trans, &inode_iter);
1172         return ret;
1173 delete:
1174         ret = bch2_btree_bit_mod_buffered(trans, BTREE_ID_deleted_inodes, pos, false);
1175         goto out;
1176 }
1177
1178 int bch2_delete_dead_inodes(struct bch_fs *c)
1179 {
1180         struct btree_trans *trans = bch2_trans_get(c);
1181         bool need_another_pass;
1182         int ret;
1183 again:
1184         need_another_pass = false;
1185
1186         /*
1187          * Weird transaction restart handling here because on successful delete,
1188          * bch2_inode_rm_snapshot() will return a nested transaction restart,
1189          * but we can't retry because the btree write buffer won't have been
1190          * flushed and we'd spin:
1191          */
1192         ret = for_each_btree_key_commit(trans, iter, BTREE_ID_deleted_inodes, POS_MIN,
1193                                         BTREE_ITER_PREFETCH|BTREE_ITER_ALL_SNAPSHOTS, k,
1194                                         NULL, NULL, BCH_TRANS_COMMIT_no_enospc, ({
1195                 ret = may_delete_deleted_inode(trans, &iter, k.k->p, &need_another_pass);
1196                 if (ret > 0) {
1197                         bch_verbose(c, "deleting unlinked inode %llu:%u", k.k->p.offset, k.k->p.snapshot);
1198
1199                         ret = bch2_inode_rm_snapshot(trans, k.k->p.offset, k.k->p.snapshot);
1200                         /*
1201                          * We don't want to loop here: a transaction restart
1202                          * error here means we handled a transaction restart and
1203                          * we're actually done, but if we loop we'll retry the
1204                          * same key because the write buffer hasn't been flushed
1205                          * yet
1206                          */
1207                         if (bch2_err_matches(ret, BCH_ERR_transaction_restart)) {
1208                                 ret = 0;
1209                                 continue;
1210                         }
1211                 }
1212
1213                 ret;
1214         }));
1215
1216         if (!ret && need_another_pass) {
1217                 ret = bch2_btree_write_buffer_flush_sync(trans);
1218                 if (ret)
1219                         goto err;
1220                 goto again;
1221         }
1222 err:
1223         bch2_trans_put(trans);
1224         return ret;
1225 }