git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/bkey.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _BCACHEFS_BKEY_H
   3 #define _BCACHEFS_BKEY_H
   4
   5 #include <linux/bug.h>
   6 #include "bcachefs_format.h"
   7
   8 #include "util.h"
   9 #include "vstructs.h"
  10
  11 #ifdef CONFIG_X86_64
  12 #define HAVE_BCACHEFS_COMPILED_UNPACK   1
  13 #endif
  14
  15 void bch2_to_binary(char *, const u64 *, unsigned);
  16
  17 /* bkey with split value, const */
  18 struct bkey_s_c {
  19         const struct bkey       *k;
  20         const struct bch_val    *v;
  21 };
  22
  23 /* bkey with split value */
  24 struct bkey_s {
  25         union {
  26         struct {
  27                 struct bkey     *k;
  28                 struct bch_val  *v;
  29         };
  30         struct bkey_s_c         s_c;
  31         };
  32 };
  33
  34 #define bkey_next(_k)           vstruct_next(_k)
  35
  36 #define bkey_val_u64s(_k)       ((_k)->u64s - BKEY_U64s)
  37
  38 static inline size_t bkey_val_bytes(const struct bkey *k)
  39 {
  40         return bkey_val_u64s(k) * sizeof(u64);
  41 }
  42
  43 static inline void set_bkey_val_u64s(struct bkey *k, unsigned val_u64s)
  44 {
  45         k->u64s = BKEY_U64s + val_u64s;
  46 }
  47
  48 static inline void set_bkey_val_bytes(struct bkey *k, unsigned bytes)
  49 {
  50         k->u64s = BKEY_U64s + DIV_ROUND_UP(bytes, sizeof(u64));
  51 }
  52
  53 #define bkey_val_end(_k)        ((void *) (((u64 *) (_k).v) + bkey_val_u64s((_k).k)))
  54
  55 #define bkey_deleted(_k)        ((_k)->type == KEY_TYPE_deleted)
  56
  57 #define bkey_whiteout(_k)                               \
  58         ((_k)->type == KEY_TYPE_deleted || (_k)->type == KEY_TYPE_discard)
  59
  60 enum bkey_lr_packed {
  61         BKEY_PACKED_BOTH,
  62         BKEY_PACKED_RIGHT,
  63         BKEY_PACKED_LEFT,
  64         BKEY_PACKED_NONE,
  65 };
  66
  67 #define bkey_lr_packed(_l, _r)                                          \
  68         ((_l)->format + ((_r)->format << 1))
  69
  70 #define bkey_copy(_dst, _src)                                   \
  71 do {                                                            \
  72         BUILD_BUG_ON(!type_is(_dst, struct bkey_i *) &&         \
  73                      !type_is(_dst, struct bkey_packed *));     \
  74         BUILD_BUG_ON(!type_is(_src, struct bkey_i *) &&         \
  75                      !type_is(_src, struct bkey_packed *));     \
  76         EBUG_ON((u64 *) (_dst) > (u64 *) (_src) &&              \
  77                 (u64 *) (_dst) < (u64 *) (_src) +               \
  78                 ((struct bkey *) (_src))->u64s);                \
  79                                                                 \
  80         memcpy_u64s_small((_dst), (_src),                       \
  81                           ((struct bkey *) (_src))->u64s);      \
  82 } while (0)
  83
  84 struct btree;
  85
  86 struct bkey_format_state {
  87         u64 field_min[BKEY_NR_FIELDS];
  88         u64 field_max[BKEY_NR_FIELDS];
  89 };
  90
  91 void bch2_bkey_format_init(struct bkey_format_state *);
  92 void bch2_bkey_format_add_key(struct bkey_format_state *, const struct bkey *);
  93 void bch2_bkey_format_add_pos(struct bkey_format_state *, struct bpos);
  94 struct bkey_format bch2_bkey_format_done(struct bkey_format_state *);
  95 const char *bch2_bkey_format_validate(struct bkey_format *);
  96
  97 __pure
  98 unsigned bch2_bkey_greatest_differing_bit(const struct btree *,
  99                                           const struct bkey_packed *,
 100                                           const struct bkey_packed *);
 101 __pure
 102 unsigned bch2_bkey_ffs(const struct btree *, const struct bkey_packed *);
 103
 104 __pure
 105 int __bch2_bkey_cmp_packed_format_checked(const struct bkey_packed *,
 106                                      const struct bkey_packed *,
 107                                      const struct btree *);
 108
 109 __pure
 110 int __bch2_bkey_cmp_left_packed_format_checked(const struct btree *,
 111                                           const struct bkey_packed *,
 112                                           const struct bpos *);
 113
 114 __pure
 115 int bch2_bkey_cmp_packed(const struct btree *,
 116                          const struct bkey_packed *,
 117                          const struct bkey_packed *);
 118
 119 __pure
 120 int __bch2_bkey_cmp_left_packed(const struct btree *,
 121                                 const struct bkey_packed *,
 122                                 const struct bpos *);
 123
 124 static inline __pure
 125 int bkey_cmp_left_packed(const struct btree *b,
 126                          const struct bkey_packed *l, const struct bpos *r)
 127 {
 128         return __bch2_bkey_cmp_left_packed(b, l, r);
 129 }
 130
 131 /*
 132  * we prefer to pass bpos by ref, but it's often enough terribly convenient to
 133  * pass it by by val... as much as I hate c++, const ref would be nice here:
 134  */
 135 __pure __flatten
 136 static inline int bkey_cmp_left_packed_byval(const struct btree *b,
 137                                              const struct bkey_packed *l,
 138                                              struct bpos r)
 139 {
 140         return bkey_cmp_left_packed(b, l, &r);
 141 }
 142
 143 static __always_inline int bpos_cmp(struct bpos l, struct bpos r)
 144 {
 145         return  cmp_int(l.inode,    r.inode) ?:
 146                 cmp_int(l.offset,   r.offset) ?:
 147                 cmp_int(l.snapshot, r.snapshot);
 148 }
 149
 150 static __always_inline int bkey_cmp(struct bpos l, struct bpos r)
 151 {
 152         return  cmp_int(l.inode,    r.inode) ?:
 153                 cmp_int(l.offset,   r.offset);
 154 }
 155
 156 static inline struct bpos bpos_min(struct bpos l, struct bpos r)
 157 {
 158         return bpos_cmp(l, r) < 0 ? l : r;
 159 }
 160
 161 static inline struct bpos bpos_max(struct bpos l, struct bpos r)
 162 {
 163         return bpos_cmp(l, r) > 0 ? l : r;
 164 }
 165
 166 #define sbb(a, b, borrow)                               \
 167 do {                                                    \
 168         typeof(a) d1, d2;                               \
 169                                                         \
 170         d1 = a - borrow;                                \
 171         borrow  = d1 > a;                               \
 172                                                         \
 173         d2 = d1 - b;                                    \
 174         borrow += d2 > d1;                              \
 175         a = d2;                                         \
 176 } while (0)
 177
 178 /* returns a - b: */
 179 static inline struct bpos bpos_sub(struct bpos a, struct bpos b)
 180 {
 181         int borrow = 0;
 182
 183         sbb(a.snapshot, b.snapshot,     borrow);
 184         sbb(a.offset,   b.offset,       borrow);
 185         sbb(a.inode,    b.inode,        borrow);
 186         return a;
 187 }
 188
 189 static inline struct bpos bpos_diff(struct bpos l, struct bpos r)
 190 {
 191         if (bpos_cmp(l, r) > 0)
 192                 swap(l, r);
 193
 194         return bpos_sub(r, l);
 195 }
 196
 197 void bch2_bpos_swab(struct bpos *);
 198 void bch2_bkey_swab_key(const struct bkey_format *, struct bkey_packed *);
 199
 200 static __always_inline int bversion_cmp(struct bversion l, struct bversion r)
 201 {
 202         return  cmp_int(l.hi, r.hi) ?:
 203                 cmp_int(l.lo, r.lo);
 204 }
 205
 206 #define ZERO_VERSION    ((struct bversion) { .hi = 0, .lo = 0 })
 207 #define MAX_VERSION     ((struct bversion) { .hi = ~0, .lo = ~0ULL })
 208
 209 static __always_inline int bversion_zero(struct bversion v)
 210 {
 211         return !bversion_cmp(v, ZERO_VERSION);
 212 }
 213
 214 #ifdef CONFIG_BCACHEFS_DEBUG
 215 /* statement expressions confusing unlikely()? */
 216 #define bkey_packed(_k)                                                 \
 217         ({ EBUG_ON((_k)->format > KEY_FORMAT_CURRENT);                  \
 218          (_k)->format != KEY_FORMAT_CURRENT; })
 219 #else
 220 #define bkey_packed(_k)         ((_k)->format != KEY_FORMAT_CURRENT)
 221 #endif
 222
 223 /*
 224  * It's safe to treat an unpacked bkey as a packed one, but not the reverse
 225  */
 226 static inline struct bkey_packed *bkey_to_packed(struct bkey_i *k)
 227 {
 228         return (struct bkey_packed *) k;
 229 }
 230
 231 static inline const struct bkey_packed *bkey_to_packed_c(const struct bkey_i *k)
 232 {
 233         return (const struct bkey_packed *) k;
 234 }
 235
 236 static inline struct bkey_i *packed_to_bkey(struct bkey_packed *k)
 237 {
 238         return bkey_packed(k) ? NULL : (struct bkey_i *) k;
 239 }
 240
 241 static inline const struct bkey *packed_to_bkey_c(const struct bkey_packed *k)
 242 {
 243         return bkey_packed(k) ? NULL : (const struct bkey *) k;
 244 }
 245
 246 static inline unsigned bkey_format_key_bits(const struct bkey_format *format)
 247 {
 248         return format->bits_per_field[BKEY_FIELD_INODE] +
 249                 format->bits_per_field[BKEY_FIELD_OFFSET] +
 250                 format->bits_per_field[BKEY_FIELD_SNAPSHOT];
 251 }
 252
 253 static inline struct bpos bpos_successor(struct bpos p)
 254 {
 255         if (!++p.snapshot &&
 256             !++p.offset &&
 257             !++p.inode)
 258                 BUG();
 259
 260         return p;
 261 }
 262
 263 static inline struct bpos bpos_predecessor(struct bpos p)
 264 {
 265         if (!p.snapshot-- &&
 266             !p.offset-- &&
 267             !p.inode--)
 268                 BUG();
 269
 270         return p;
 271 }
 272
 273 static inline struct bpos bpos_nosnap_successor(struct bpos p)
 274 {
 275         p.snapshot = 0;
 276
 277         if (!++p.offset &&
 278             !++p.inode)
 279                 BUG();
 280
 281         return p;
 282 }
 283
 284 static inline struct bpos bpos_nosnap_predecessor(struct bpos p)
 285 {
 286         p.snapshot = 0;
 287
 288         if (!p.offset-- &&
 289             !p.inode--)
 290                 BUG();
 291
 292         return p;
 293 }
 294
 295 static inline u64 bkey_start_offset(const struct bkey *k)
 296 {
 297         return k->p.offset - k->size;
 298 }
 299
 300 static inline struct bpos bkey_start_pos(const struct bkey *k)
 301 {
 302         return (struct bpos) {
 303                 .inode          = k->p.inode,
 304                 .offset         = bkey_start_offset(k),
 305                 .snapshot       = k->p.snapshot,
 306         };
 307 }
 308
 309 /* Packed helpers */
 310
 311 static inline unsigned bkeyp_key_u64s(const struct bkey_format *format,
 312                                       const struct bkey_packed *k)
 313 {
 314         unsigned ret = bkey_packed(k) ? format->key_u64s : BKEY_U64s;
 315
 316         EBUG_ON(k->u64s < ret);
 317         return ret;
 318 }
 319
 320 static inline unsigned bkeyp_key_bytes(const struct bkey_format *format,
 321                                        const struct bkey_packed *k)
 322 {
 323         return bkeyp_key_u64s(format, k) * sizeof(u64);
 324 }
 325
 326 static inline unsigned bkeyp_val_u64s(const struct bkey_format *format,
 327                                       const struct bkey_packed *k)
 328 {
 329         return k->u64s - bkeyp_key_u64s(format, k);
 330 }
 331
 332 static inline size_t bkeyp_val_bytes(const struct bkey_format *format,
 333                                      const struct bkey_packed *k)
 334 {
 335         return bkeyp_val_u64s(format, k) * sizeof(u64);
 336 }
 337
 338 static inline void set_bkeyp_val_u64s(const struct bkey_format *format,
 339                                       struct bkey_packed *k, unsigned val_u64s)
 340 {
 341         k->u64s = bkeyp_key_u64s(format, k) + val_u64s;
 342 }
 343
 344 #define bkeyp_val(_format, _k)                                          \
 345          ((struct bch_val *) ((_k)->_data + bkeyp_key_u64s(_format, _k)))
 346
 347 extern const struct bkey_format bch2_bkey_format_current;
 348
 349 bool bch2_bkey_transform(const struct bkey_format *,
 350                          struct bkey_packed *,
 351                          const struct bkey_format *,
 352                          const struct bkey_packed *);
 353
 354 struct bkey __bch2_bkey_unpack_key(const struct bkey_format *,
 355                                    const struct bkey_packed *);
 356
 357 #ifndef HAVE_BCACHEFS_COMPILED_UNPACK
 358 struct bpos __bkey_unpack_pos(const struct bkey_format *,
 359                               const struct bkey_packed *);
 360 #endif
 361
 362 bool bch2_bkey_pack_key(struct bkey_packed *, const struct bkey *,
 363                    const struct bkey_format *);
 364
 365 enum bkey_pack_pos_ret {
 366         BKEY_PACK_POS_EXACT,
 367         BKEY_PACK_POS_SMALLER,
 368         BKEY_PACK_POS_FAIL,
 369 };
 370
 371 enum bkey_pack_pos_ret bch2_bkey_pack_pos_lossy(struct bkey_packed *, struct bpos,
 372                                            const struct btree *);
 373
 374 static inline bool bkey_pack_pos(struct bkey_packed *out, struct bpos in,
 375                                  const struct btree *b)
 376 {
 377         return bch2_bkey_pack_pos_lossy(out, in, b) == BKEY_PACK_POS_EXACT;
 378 }
 379
 380 void bch2_bkey_unpack(const struct btree *, struct bkey_i *,
 381                  const struct bkey_packed *);
 382 bool bch2_bkey_pack(struct bkey_packed *, const struct bkey_i *,
 383                const struct bkey_format *);
 384
 385 static inline u64 bkey_field_max(const struct bkey_format *f,
 386                                  enum bch_bkey_fields nr)
 387 {
 388         return f->bits_per_field[nr] < 64
 389                 ? (le64_to_cpu(f->field_offset[nr]) +
 390                    ~(~0ULL << f->bits_per_field[nr]))
 391                 : U64_MAX;
 392 }
 393
 394 #ifdef HAVE_BCACHEFS_COMPILED_UNPACK
 395
 396 int bch2_compile_bkey_format(const struct bkey_format *, void *);
 397
 398 #else
 399
 400 static inline int bch2_compile_bkey_format(const struct bkey_format *format,
 401                                           void *out) { return 0; }
 402
 403 #endif
 404
 405 static inline void bkey_reassemble(struct bkey_i *dst,
 406                                    struct bkey_s_c src)
 407 {
 408         dst->k = *src.k;
 409         memcpy_u64s_small(&dst->v, src.v, bkey_val_u64s(src.k));
 410 }
 411
 412 #define bkey_s_null             ((struct bkey_s)   { .k = NULL })
 413 #define bkey_s_c_null           ((struct bkey_s_c) { .k = NULL })
 414
 415 #define bkey_s_err(err)         ((struct bkey_s)   { .k = ERR_PTR(err) })
 416 #define bkey_s_c_err(err)       ((struct bkey_s_c) { .k = ERR_PTR(err) })
 417
 418 static inline struct bkey_s bkey_to_s(struct bkey *k)
 419 {
 420         return (struct bkey_s) { .k = k, .v = NULL };
 421 }
 422
 423 static inline struct bkey_s_c bkey_to_s_c(const struct bkey *k)
 424 {
 425         return (struct bkey_s_c) { .k = k, .v = NULL };
 426 }
 427
 428 static inline struct bkey_s bkey_i_to_s(struct bkey_i *k)
 429 {
 430         return (struct bkey_s) { .k = &k->k, .v = &k->v };
 431 }
 432
 433 static inline struct bkey_s_c bkey_i_to_s_c(const struct bkey_i *k)
 434 {
 435         return (struct bkey_s_c) { .k = &k->k, .v = &k->v };
 436 }
 437
 438 /*
 439  * For a given type of value (e.g. struct bch_extent), generates the types for
 440  * bkey + bch_extent - inline, split, split const - and also all the conversion
 441  * functions, which also check that the value is of the correct type.
 442  *
 443  * We use anonymous unions for upcasting - e.g. converting from e.g. a
 444  * bkey_i_extent to a bkey_i - since that's always safe, instead of conversion
 445  * functions.
 446  */
 447 #define x(name, ...)                                    \
 448 struct bkey_i_##name {                                                  \
 449         union {                                                         \
 450                 struct bkey             k;                              \
 451                 struct bkey_i           k_i;                            \
 452         };                                                              \
 453         struct bch_##name               v;                              \
 454 };                                                                      \
 455                                                                         \
 456 struct bkey_s_c_##name {                                                \
 457         union {                                                         \
 458         struct {                                                        \
 459                 const struct bkey       *k;                             \
 460                 const struct bch_##name *v;                             \
 461         };                                                              \
 462         struct bkey_s_c                 s_c;                            \
 463         };                                                              \
 464 };                                                                      \
 465                                                                         \
 466 struct bkey_s_##name {                                                  \
 467         union {                                                         \
 468         struct {                                                        \
 469                 struct bkey             *k;                             \
 470                 struct bch_##name       *v;                             \
 471         };                                                              \
 472         struct bkey_s_c_##name          c;                              \
 473         struct bkey_s                   s;                              \
 474         struct bkey_s_c                 s_c;                            \
 475         };                                                              \
 476 };                                                                      \
 477                                                                         \
 478 static inline struct bkey_i_##name *bkey_i_to_##name(struct bkey_i *k)  \
 479 {                                                                       \
 480         EBUG_ON(k->k.type != KEY_TYPE_##name);                          \
 481         return container_of(&k->k, struct bkey_i_##name, k);            \
 482 }                                                                       \
 483                                                                         \
 484 static inline const struct bkey_i_##name *                              \
 485 bkey_i_to_##name##_c(const struct bkey_i *k)                            \
 486 {                                                                       \
 487         EBUG_ON(k->k.type != KEY_TYPE_##name);                          \
 488         return container_of(&k->k, struct bkey_i_##name, k);            \
 489 }                                                                       \
 490                                                                         \
 491 static inline struct bkey_s_##name bkey_s_to_##name(struct bkey_s k)    \
 492 {                                                                       \
 493         EBUG_ON(k.k->type != KEY_TYPE_##name);                          \
 494         return (struct bkey_s_##name) {                                 \
 495                 .k = k.k,                                               \
 496                 .v = container_of(k.v, struct bch_##name, v),           \
 497         };                                                              \
 498 }                                                                       \
 499                                                                         \
 500 static inline struct bkey_s_c_##name bkey_s_c_to_##name(struct bkey_s_c k)\
 501 {                                                                       \
 502         EBUG_ON(k.k->type != KEY_TYPE_##name);                          \
 503         return (struct bkey_s_c_##name) {                               \
 504                 .k = k.k,                                               \
 505                 .v = container_of(k.v, struct bch_##name, v),           \
 506         };                                                              \
 507 }                                                                       \
 508                                                                         \
 509 static inline struct bkey_s_##name name##_i_to_s(struct bkey_i_##name *k)\
 510 {                                                                       \
 511         return (struct bkey_s_##name) {                                 \
 512                 .k = &k->k,                                             \
 513                 .v = &k->v,                                             \
 514         };                                                              \
 515 }                                                                       \
 516                                                                         \
 517 static inline struct bkey_s_c_##name                                    \
 518 name##_i_to_s_c(const struct bkey_i_##name *k)                          \
 519 {                                                                       \
 520         return (struct bkey_s_c_##name) {                               \
 521                 .k = &k->k,                                             \
 522                 .v = &k->v,                                             \
 523         };                                                              \
 524 }                                                                       \
 525                                                                         \
 526 static inline struct bkey_s_##name bkey_i_to_s_##name(struct bkey_i *k) \
 527 {                                                                       \
 528         EBUG_ON(k->k.type != KEY_TYPE_##name);                          \
 529         return (struct bkey_s_##name) {                                 \
 530                 .k = &k->k,                                             \
 531                 .v = container_of(&k->v, struct bch_##name, v),         \
 532         };                                                              \
 533 }                                                                       \
 534                                                                         \
 535 static inline struct bkey_s_c_##name                                    \
 536 bkey_i_to_s_c_##name(const struct bkey_i *k)                            \
 537 {                                                                       \
 538         EBUG_ON(k->k.type != KEY_TYPE_##name);                          \
 539         return (struct bkey_s_c_##name) {                               \
 540                 .k = &k->k,                                             \
 541                 .v = container_of(&k->v, struct bch_##name, v),         \
 542         };                                                              \
 543 }                                                                       \
 544                                                                         \
 545 static inline struct bkey_i_##name *bkey_##name##_init(struct bkey_i *_k)\
 546 {                                                                       \
 547         struct bkey_i_##name *k =                                       \
 548                 container_of(&_k->k, struct bkey_i_##name, k);          \
 549                                                                         \
 550         bkey_init(&k->k);                                               \
 551         memset(&k->v, 0, sizeof(k->v));                                 \
 552         k->k.type = KEY_TYPE_##name;                                    \
 553         set_bkey_val_bytes(&k->k, sizeof(k->v));                        \
 554                                                                         \
 555         return k;                                                       \
 556 }
 557
 558 BCH_BKEY_TYPES();
 559 #undef x
 560
 561 /* byte order helpers */
 562
 563 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 564
 565 static inline unsigned high_word_offset(const struct bkey_format *f)
 566 {
 567         return f->key_u64s - 1;
 568 }
 569
 570 #define high_bit_offset         0
 571 #define nth_word(p, n)          ((p) - (n))
 572
 573 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 574
 575 static inline unsigned high_word_offset(const struct bkey_format *f)
 576 {
 577         return 0;
 578 }
 579
 580 #define high_bit_offset         KEY_PACKED_BITS_START
 581 #define nth_word(p, n)          ((p) + (n))
 582
 583 #else
 584 #error edit for your odd byteorder.
 585 #endif
 586
 587 #define high_word(f, k)         ((k)->_data + high_word_offset(f))
 588 #define next_word(p)            nth_word(p, 1)
 589 #define prev_word(p)            nth_word(p, -1)
 590
 591 #ifdef CONFIG_BCACHEFS_DEBUG
 592 void bch2_bkey_pack_test(void);
 593 #else
 594 static inline void bch2_bkey_pack_test(void) {}
 595 #endif
 596
 597 #endif /* _BCACHEFS_BKEY_H */