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_bkey_packed_to_binary_text(struct printbuf *,
  16                                      const struct bkey_format *,
  17                                      const struct bkey_packed *);
  18
  19 /* bkey with split value, const */
  20 struct bkey_s_c {
  21         const struct bkey       *k;
  22         const struct bch_val    *v;
  23 };
  24
  25 /* bkey with split value */
  26 struct bkey_s {
  27         union {
  28         struct {
  29                 struct bkey     *k;
  30                 struct bch_val  *v;
  31         };
  32         struct bkey_s_c         s_c;
  33         };
  34 };
  35
  36 #define bkey_next(_k)           vstruct_next(_k)
  37
  38 #define bkey_val_u64s(_k)       ((_k)->u64s - BKEY_U64s)
  39
  40 static inline size_t bkey_val_bytes(const struct bkey *k)
  41 {
  42         return bkey_val_u64s(k) * sizeof(u64);
  43 }
  44
  45 static inline void set_bkey_val_u64s(struct bkey *k, unsigned val_u64s)
  46 {
  47         unsigned u64s = BKEY_U64s + val_u64s;
  48
  49         BUG_ON(u64s > U8_MAX);
  50         k->u64s = u64s;
  51 }
  52
  53 static inline void set_bkey_val_bytes(struct bkey *k, unsigned bytes)
  54 {
  55         set_bkey_val_u64s(k, DIV_ROUND_UP(bytes, sizeof(u64)));
  56 }
  57
  58 #define bkey_val_end(_k)        ((void *) (((u64 *) (_k).v) + bkey_val_u64s((_k).k)))
  59
  60 #define bkey_deleted(_k)        ((_k)->type == KEY_TYPE_deleted)
  61
  62 #define bkey_whiteout(_k)                               \
  63         ((_k)->type == KEY_TYPE_deleted || (_k)->type == KEY_TYPE_whiteout)
  64
  65 enum bkey_lr_packed {
  66         BKEY_PACKED_BOTH,
  67         BKEY_PACKED_RIGHT,
  68         BKEY_PACKED_LEFT,
  69         BKEY_PACKED_NONE,
  70 };
  71
  72 #define bkey_lr_packed(_l, _r)                                          \
  73         ((_l)->format + ((_r)->format << 1))
  74
  75 #define bkey_copy(_dst, _src)                                   \
  76 do {                                                            \
  77         BUILD_BUG_ON(!type_is(_dst, struct bkey_i *) &&         \
  78                      !type_is(_dst, struct bkey_packed *));     \
  79         BUILD_BUG_ON(!type_is(_src, struct bkey_i *) &&         \
  80                      !type_is(_src, struct bkey_packed *));     \
  81         EBUG_ON((u64 *) (_dst) > (u64 *) (_src) &&              \
  82                 (u64 *) (_dst) < (u64 *) (_src) +               \
  83                 ((struct bkey *) (_src))->u64s);                \
  84                                                                 \
  85         memcpy_u64s_small((_dst), (_src),                       \
  86                           ((struct bkey *) (_src))->u64s);      \
  87 } while (0)
  88
  89 struct btree;
  90
  91 struct bkey_format_state {
  92         u64 field_min[BKEY_NR_FIELDS];
  93         u64 field_max[BKEY_NR_FIELDS];
  94 };
  95
  96 void bch2_bkey_format_init(struct bkey_format_state *);
  97 void bch2_bkey_format_add_key(struct bkey_format_state *, const struct bkey *);
  98 void bch2_bkey_format_add_pos(struct bkey_format_state *, struct bpos);
  99 struct bkey_format bch2_bkey_format_done(struct bkey_format_state *);
 100 const char *bch2_bkey_format_validate(struct bkey_format *);
 101
 102 __pure
 103 unsigned bch2_bkey_greatest_differing_bit(const struct btree *,
 104                                           const struct bkey_packed *,
 105                                           const struct bkey_packed *);
 106 __pure
 107 unsigned bch2_bkey_ffs(const struct btree *, const struct bkey_packed *);
 108
 109 __pure
 110 int __bch2_bkey_cmp_packed_format_checked(const struct bkey_packed *,
 111                                      const struct bkey_packed *,
 112                                      const struct btree *);
 113
 114 __pure
 115 int __bch2_bkey_cmp_left_packed_format_checked(const struct btree *,
 116                                           const struct bkey_packed *,
 117                                           const struct bpos *);
 118
 119 __pure
 120 int bch2_bkey_cmp_packed(const struct btree *,
 121                          const struct bkey_packed *,
 122                          const struct bkey_packed *);
 123
 124 __pure
 125 int __bch2_bkey_cmp_left_packed(const struct btree *,
 126                                 const struct bkey_packed *,
 127                                 const struct bpos *);
 128
 129 static inline __pure
 130 int bkey_cmp_left_packed(const struct btree *b,
 131                          const struct bkey_packed *l, const struct bpos *r)
 132 {
 133         return __bch2_bkey_cmp_left_packed(b, l, r);
 134 }
 135
 136 /*
 137  * we prefer to pass bpos by ref, but it's often enough terribly convenient to
 138  * pass it by by val... as much as I hate c++, const ref would be nice here:
 139  */
 140 __pure __flatten
 141 static inline int bkey_cmp_left_packed_byval(const struct btree *b,
 142                                              const struct bkey_packed *l,
 143                                              struct bpos r)
 144 {
 145         return bkey_cmp_left_packed(b, l, &r);
 146 }
 147
 148 static __always_inline int bpos_cmp(struct bpos l, struct bpos r)
 149 {
 150         return  cmp_int(l.inode,    r.inode) ?:
 151                 cmp_int(l.offset,   r.offset) ?:
 152                 cmp_int(l.snapshot, r.snapshot);
 153 }
 154
 155 static __always_inline int bkey_cmp(struct bpos l, struct bpos r)
 156 {
 157         return  cmp_int(l.inode,    r.inode) ?:
 158                 cmp_int(l.offset,   r.offset);
 159 }
 160
 161 static inline struct bpos bpos_min(struct bpos l, struct bpos r)
 162 {
 163         return bpos_cmp(l, r) < 0 ? l : r;
 164 }
 165
 166 static inline struct bpos bpos_max(struct bpos l, struct bpos r)
 167 {
 168         return bpos_cmp(l, r) > 0 ? l : r;
 169 }
 170
 171 void bch2_bpos_swab(struct bpos *);
 172 void bch2_bkey_swab_key(const struct bkey_format *, struct bkey_packed *);
 173
 174 static __always_inline int bversion_cmp(struct bversion l, struct bversion r)
 175 {
 176         return  cmp_int(l.hi, r.hi) ?:
 177                 cmp_int(l.lo, r.lo);
 178 }
 179
 180 #define ZERO_VERSION    ((struct bversion) { .hi = 0, .lo = 0 })
 181 #define MAX_VERSION     ((struct bversion) { .hi = ~0, .lo = ~0ULL })
 182
 183 static __always_inline int bversion_zero(struct bversion v)
 184 {
 185         return !bversion_cmp(v, ZERO_VERSION);
 186 }
 187
 188 #ifdef CONFIG_BCACHEFS_DEBUG
 189 /* statement expressions confusing unlikely()? */
 190 #define bkey_packed(_k)                                                 \
 191         ({ EBUG_ON((_k)->format > KEY_FORMAT_CURRENT);                  \
 192          (_k)->format != KEY_FORMAT_CURRENT; })
 193 #else
 194 #define bkey_packed(_k)         ((_k)->format != KEY_FORMAT_CURRENT)
 195 #endif
 196
 197 /*
 198  * It's safe to treat an unpacked bkey as a packed one, but not the reverse
 199  */
 200 static inline struct bkey_packed *bkey_to_packed(struct bkey_i *k)
 201 {
 202         return (struct bkey_packed *) k;
 203 }
 204
 205 static inline const struct bkey_packed *bkey_to_packed_c(const struct bkey_i *k)
 206 {
 207         return (const struct bkey_packed *) k;
 208 }
 209
 210 static inline struct bkey_i *packed_to_bkey(struct bkey_packed *k)
 211 {
 212         return bkey_packed(k) ? NULL : (struct bkey_i *) k;
 213 }
 214
 215 static inline const struct bkey *packed_to_bkey_c(const struct bkey_packed *k)
 216 {
 217         return bkey_packed(k) ? NULL : (const struct bkey *) k;
 218 }
 219
 220 static inline unsigned bkey_format_key_bits(const struct bkey_format *format)
 221 {
 222         return format->bits_per_field[BKEY_FIELD_INODE] +
 223                 format->bits_per_field[BKEY_FIELD_OFFSET] +
 224                 format->bits_per_field[BKEY_FIELD_SNAPSHOT];
 225 }
 226
 227 static inline struct bpos bpos_successor(struct bpos p)
 228 {
 229         if (!++p.snapshot &&
 230             !++p.offset &&
 231             !++p.inode)
 232                 BUG();
 233
 234         return p;
 235 }
 236
 237 static inline struct bpos bpos_predecessor(struct bpos p)
 238 {
 239         if (!p.snapshot-- &&
 240             !p.offset-- &&
 241             !p.inode--)
 242                 BUG();
 243
 244         return p;
 245 }
 246
 247 static inline struct bpos bpos_nosnap_successor(struct bpos p)
 248 {
 249         p.snapshot = 0;
 250
 251         if (!++p.offset &&
 252             !++p.inode)
 253                 BUG();
 254
 255         return p;
 256 }
 257
 258 static inline struct bpos bpos_nosnap_predecessor(struct bpos p)
 259 {
 260         p.snapshot = 0;
 261
 262         if (!p.offset-- &&
 263             !p.inode--)
 264                 BUG();
 265
 266         return p;
 267 }
 268
 269 static inline u64 bkey_start_offset(const struct bkey *k)
 270 {
 271         return k->p.offset - k->size;
 272 }
 273
 274 static inline struct bpos bkey_start_pos(const struct bkey *k)
 275 {
 276         return (struct bpos) {
 277                 .inode          = k->p.inode,
 278                 .offset         = bkey_start_offset(k),
 279                 .snapshot       = k->p.snapshot,
 280         };
 281 }
 282
 283 /* Packed helpers */
 284
 285 static inline unsigned bkeyp_key_u64s(const struct bkey_format *format,
 286                                       const struct bkey_packed *k)
 287 {
 288         unsigned ret = bkey_packed(k) ? format->key_u64s : BKEY_U64s;
 289
 290         EBUG_ON(k->u64s < ret);
 291         return ret;
 292 }
 293
 294 static inline unsigned bkeyp_key_bytes(const struct bkey_format *format,
 295                                        const struct bkey_packed *k)
 296 {
 297         return bkeyp_key_u64s(format, k) * sizeof(u64);
 298 }
 299
 300 static inline unsigned bkeyp_val_u64s(const struct bkey_format *format,
 301                                       const struct bkey_packed *k)
 302 {
 303         return k->u64s - bkeyp_key_u64s(format, k);
 304 }
 305
 306 static inline size_t bkeyp_val_bytes(const struct bkey_format *format,
 307                                      const struct bkey_packed *k)
 308 {
 309         return bkeyp_val_u64s(format, k) * sizeof(u64);
 310 }
 311
 312 static inline void set_bkeyp_val_u64s(const struct bkey_format *format,
 313                                       struct bkey_packed *k, unsigned val_u64s)
 314 {
 315         k->u64s = bkeyp_key_u64s(format, k) + val_u64s;
 316 }
 317
 318 #define bkeyp_val(_format, _k)                                          \
 319          ((struct bch_val *) ((_k)->_data + bkeyp_key_u64s(_format, _k)))
 320
 321 extern const struct bkey_format bch2_bkey_format_current;
 322
 323 bool bch2_bkey_transform(const struct bkey_format *,
 324                          struct bkey_packed *,
 325                          const struct bkey_format *,
 326                          const struct bkey_packed *);
 327
 328 struct bkey __bch2_bkey_unpack_key(const struct bkey_format *,
 329                                    const struct bkey_packed *);
 330
 331 #ifndef HAVE_BCACHEFS_COMPILED_UNPACK
 332 struct bpos __bkey_unpack_pos(const struct bkey_format *,
 333                               const struct bkey_packed *);
 334 #endif
 335
 336 bool bch2_bkey_pack_key(struct bkey_packed *, const struct bkey *,
 337                    const struct bkey_format *);
 338
 339 enum bkey_pack_pos_ret {
 340         BKEY_PACK_POS_EXACT,
 341         BKEY_PACK_POS_SMALLER,
 342         BKEY_PACK_POS_FAIL,
 343 };
 344
 345 enum bkey_pack_pos_ret bch2_bkey_pack_pos_lossy(struct bkey_packed *, struct bpos,
 346                                            const struct btree *);
 347
 348 static inline bool bkey_pack_pos(struct bkey_packed *out, struct bpos in,
 349                                  const struct btree *b)
 350 {
 351         return bch2_bkey_pack_pos_lossy(out, in, b) == BKEY_PACK_POS_EXACT;
 352 }
 353
 354 void bch2_bkey_unpack(const struct btree *, struct bkey_i *,
 355                  const struct bkey_packed *);
 356 bool bch2_bkey_pack(struct bkey_packed *, const struct bkey_i *,
 357                const struct bkey_format *);
 358
 359 static inline u64 bkey_field_max(const struct bkey_format *f,
 360                                  enum bch_bkey_fields nr)
 361 {
 362         return f->bits_per_field[nr] < 64
 363                 ? (le64_to_cpu(f->field_offset[nr]) +
 364                    ~(~0ULL << f->bits_per_field[nr]))
 365                 : U64_MAX;
 366 }
 367
 368 #ifdef HAVE_BCACHEFS_COMPILED_UNPACK
 369
 370 int bch2_compile_bkey_format(const struct bkey_format *, void *);
 371
 372 #else
 373
 374 static inline int bch2_compile_bkey_format(const struct bkey_format *format,
 375                                           void *out) { return 0; }
 376
 377 #endif
 378
 379 static inline void bkey_reassemble(struct bkey_i *dst,
 380                                    struct bkey_s_c src)
 381 {
 382         dst->k = *src.k;
 383         memcpy_u64s_small(&dst->v, src.v, bkey_val_u64s(src.k));
 384 }
 385
 386 #define bkey_s_null             ((struct bkey_s)   { .k = NULL })
 387 #define bkey_s_c_null           ((struct bkey_s_c) { .k = NULL })
 388
 389 #define bkey_s_err(err)         ((struct bkey_s)   { .k = ERR_PTR(err) })
 390 #define bkey_s_c_err(err)       ((struct bkey_s_c) { .k = ERR_PTR(err) })
 391
 392 static inline struct bkey_s bkey_to_s(struct bkey *k)
 393 {
 394         return (struct bkey_s) { .k = k, .v = NULL };
 395 }
 396
 397 static inline struct bkey_s_c bkey_to_s_c(const struct bkey *k)
 398 {
 399         return (struct bkey_s_c) { .k = k, .v = NULL };
 400 }
 401
 402 static inline struct bkey_s bkey_i_to_s(struct bkey_i *k)
 403 {
 404         return (struct bkey_s) { .k = &k->k, .v = &k->v };
 405 }
 406
 407 static inline struct bkey_s_c bkey_i_to_s_c(const struct bkey_i *k)
 408 {
 409         return (struct bkey_s_c) { .k = &k->k, .v = &k->v };
 410 }
 411
 412 /*
 413  * For a given type of value (e.g. struct bch_extent), generates the types for
 414  * bkey + bch_extent - inline, split, split const - and also all the conversion
 415  * functions, which also check that the value is of the correct type.
 416  *
 417  * We use anonymous unions for upcasting - e.g. converting from e.g. a
 418  * bkey_i_extent to a bkey_i - since that's always safe, instead of conversion
 419  * functions.
 420  */
 421 #define x(name, ...)                                    \
 422 struct bkey_i_##name {                                                  \
 423         union {                                                         \
 424                 struct bkey             k;                              \
 425                 struct bkey_i           k_i;                            \
 426         };                                                              \
 427         struct bch_##name               v;                              \
 428 };                                                                      \
 429                                                                         \
 430 struct bkey_s_c_##name {                                                \
 431         union {                                                         \
 432         struct {                                                        \
 433                 const struct bkey       *k;                             \
 434                 const struct bch_##name *v;                             \
 435         };                                                              \
 436         struct bkey_s_c                 s_c;                            \
 437         };                                                              \
 438 };                                                                      \
 439                                                                         \
 440 struct bkey_s_##name {                                                  \
 441         union {                                                         \
 442         struct {                                                        \
 443                 struct bkey             *k;                             \
 444                 struct bch_##name       *v;                             \
 445         };                                                              \
 446         struct bkey_s_c_##name          c;                              \
 447         struct bkey_s                   s;                              \
 448         struct bkey_s_c                 s_c;                            \
 449         };                                                              \
 450 };                                                                      \
 451                                                                         \
 452 static inline struct bkey_i_##name *bkey_i_to_##name(struct bkey_i *k)  \
 453 {                                                                       \
 454         EBUG_ON(k->k.type != KEY_TYPE_##name);                          \
 455         return container_of(&k->k, struct bkey_i_##name, k);            \
 456 }                                                                       \
 457                                                                         \
 458 static inline const struct bkey_i_##name *                              \
 459 bkey_i_to_##name##_c(const struct bkey_i *k)                            \
 460 {                                                                       \
 461         EBUG_ON(k->k.type != KEY_TYPE_##name);                          \
 462         return container_of(&k->k, struct bkey_i_##name, k);            \
 463 }                                                                       \
 464                                                                         \
 465 static inline struct bkey_s_##name bkey_s_to_##name(struct bkey_s k)    \
 466 {                                                                       \
 467         EBUG_ON(k.k->type != KEY_TYPE_##name);                          \
 468         return (struct bkey_s_##name) {                                 \
 469                 .k = k.k,                                               \
 470                 .v = container_of(k.v, struct bch_##name, v),           \
 471         };                                                              \
 472 }                                                                       \
 473                                                                         \
 474 static inline struct bkey_s_c_##name bkey_s_c_to_##name(struct bkey_s_c k)\
 475 {                                                                       \
 476         EBUG_ON(k.k->type != KEY_TYPE_##name);                          \
 477         return (struct bkey_s_c_##name) {                               \
 478                 .k = k.k,                                               \
 479                 .v = container_of(k.v, struct bch_##name, v),           \
 480         };                                                              \
 481 }                                                                       \
 482                                                                         \
 483 static inline struct bkey_s_##name name##_i_to_s(struct bkey_i_##name *k)\
 484 {                                                                       \
 485         return (struct bkey_s_##name) {                                 \
 486                 .k = &k->k,                                             \
 487                 .v = &k->v,                                             \
 488         };                                                              \
 489 }                                                                       \
 490                                                                         \
 491 static inline struct bkey_s_c_##name                                    \
 492 name##_i_to_s_c(const struct bkey_i_##name *k)                          \
 493 {                                                                       \
 494         return (struct bkey_s_c_##name) {                               \
 495                 .k = &k->k,                                             \
 496                 .v = &k->v,                                             \
 497         };                                                              \
 498 }                                                                       \
 499                                                                         \
 500 static inline struct bkey_s_##name bkey_i_to_s_##name(struct bkey_i *k) \
 501 {                                                                       \
 502         EBUG_ON(k->k.type != KEY_TYPE_##name);                          \
 503         return (struct bkey_s_##name) {                                 \
 504                 .k = &k->k,                                             \
 505                 .v = container_of(&k->v, struct bch_##name, v),         \
 506         };                                                              \
 507 }                                                                       \
 508                                                                         \
 509 static inline struct bkey_s_c_##name                                    \
 510 bkey_i_to_s_c_##name(const struct bkey_i *k)                            \
 511 {                                                                       \
 512         EBUG_ON(k->k.type != KEY_TYPE_##name);                          \
 513         return (struct bkey_s_c_##name) {                               \
 514                 .k = &k->k,                                             \
 515                 .v = container_of(&k->v, struct bch_##name, v),         \
 516         };                                                              \
 517 }                                                                       \
 518                                                                         \
 519 static inline struct bkey_i_##name *bkey_##name##_init(struct bkey_i *_k)\
 520 {                                                                       \
 521         struct bkey_i_##name *k =                                       \
 522                 container_of(&_k->k, struct bkey_i_##name, k);          \
 523                                                                         \
 524         bkey_init(&k->k);                                               \
 525         memset(&k->v, 0, sizeof(k->v));                                 \
 526         k->k.type = KEY_TYPE_##name;                                    \
 527         set_bkey_val_bytes(&k->k, sizeof(k->v));                        \
 528                                                                         \
 529         return k;                                                       \
 530 }
 531
 532 BCH_BKEY_TYPES();
 533 #undef x
 534
 535 /* byte order helpers */
 536
 537 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
 538
 539 static inline unsigned high_word_offset(const struct bkey_format *f)
 540 {
 541         return f->key_u64s - 1;
 542 }
 543
 544 #define high_bit_offset         0
 545 #define nth_word(p, n)          ((p) - (n))
 546
 547 #elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
 548
 549 static inline unsigned high_word_offset(const struct bkey_format *f)
 550 {
 551         return 0;
 552 }
 553
 554 #define high_bit_offset         KEY_PACKED_BITS_START
 555 #define nth_word(p, n)          ((p) + (n))
 556
 557 #else
 558 #error edit for your odd byteorder.
 559 #endif
 560
 561 #define high_word(f, k)         ((k)->_data + high_word_offset(f))
 562 #define next_word(p)            nth_word(p, 1)
 563 #define prev_word(p)            nth_word(p, -1)
 564
 565 #ifdef CONFIG_BCACHEFS_DEBUG
 566 void bch2_bkey_pack_test(void);
 567 #else
 568 static inline void bch2_bkey_pack_test(void) {}
 569 #endif
 570
 571 #endif /* _BCACHEFS_BKEY_H */