fs/bcachefs/buckets.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Code for manipulating bucket marks for garbage collection.
   4  *
   5  * Copyright 2014 Datera, Inc.
   6  */
   7
   8 #ifndef _BUCKETS_H
   9 #define _BUCKETS_H
  10
  11 #include "buckets_types.h"
  12 #include "extents.h"
  13 #include "sb-members.h"
  14
  15 static inline u64 sector_to_bucket(const struct bch_dev *ca, sector_t s)
  16 {
  17         return div_u64(s, ca->mi.bucket_size);
  18 }
  19
  20 static inline sector_t bucket_to_sector(const struct bch_dev *ca, size_t b)
  21 {
  22         return ((sector_t) b) * ca->mi.bucket_size;
  23 }
  24
  25 static inline sector_t bucket_remainder(const struct bch_dev *ca, sector_t s)
  26 {
  27         u32 remainder;
  28
  29         div_u64_rem(s, ca->mi.bucket_size, &remainder);
  30         return remainder;
  31 }
  32
  33 static inline u64 sector_to_bucket_and_offset(const struct bch_dev *ca, sector_t s, u32 *offset)
  34 {
  35         return div_u64_rem(s, ca->mi.bucket_size, offset);
  36 }
  37
  38 #define for_each_bucket(_b, _buckets)                           \
  39         for (_b = (_buckets)->b + (_buckets)->first_bucket;     \
  40              _b < (_buckets)->b + (_buckets)->nbuckets; _b++)
  41
  42 /*
  43  * Ugly hack alert:
  44  *
  45  * We need to cram a spinlock in a single byte, because that's what we have left
  46  * in struct bucket, and we care about the size of these - during fsck, we need
  47  * in memory state for every single bucket on every device.
  48  *
  49  * We used to do
  50  *   while (xchg(&b->lock, 1) cpu_relax();
  51  * but, it turns out not all architectures support xchg on a single byte.
  52  *
  53  * So now we use bit_spin_lock(), with fun games since we can't burn a whole
  54  * ulong for this - we just need to make sure the lock bit always ends up in the
  55  * first byte.
  56  */
  57
  58 #if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
  59 #define BUCKET_LOCK_BITNR       0
  60 #else
  61 #define BUCKET_LOCK_BITNR       (BITS_PER_LONG - 1)
  62 #endif
  63
  64 union ulong_byte_assert {
  65         ulong   ulong;
  66         u8      byte;
  67 };
  68
  69 static inline void bucket_unlock(struct bucket *b)
  70 {
  71         BUILD_BUG_ON(!((union ulong_byte_assert) { .ulong = 1UL << BUCKET_LOCK_BITNR }).byte);
  72
  73         clear_bit_unlock(BUCKET_LOCK_BITNR, (void *) &b->lock);
  74         wake_up_bit((void *) &b->lock, BUCKET_LOCK_BITNR);
  75 }
  76
  77 static inline void bucket_lock(struct bucket *b)
  78 {
  79         wait_on_bit_lock((void *) &b->lock, BUCKET_LOCK_BITNR,
  80                          TASK_UNINTERRUPTIBLE);
  81 }
  82
  83 static inline struct bucket *gc_bucket(struct bch_dev *ca, size_t b)
  84 {
  85         return genradix_ptr(&ca->buckets_gc, b);
  86 }
  87
  88 static inline struct bucket_gens *bucket_gens(struct bch_dev *ca)
  89 {
  90         return rcu_dereference_check(ca->bucket_gens,
  91                                      !ca->fs ||
  92                                      percpu_rwsem_is_held(&ca->fs->mark_lock) ||
  93                                      lockdep_is_held(&ca->fs->state_lock) ||
  94                                      lockdep_is_held(&ca->bucket_lock));
  95 }
  96
  97 static inline u8 *bucket_gen(struct bch_dev *ca, size_t b)
  98 {
  99         struct bucket_gens *gens = bucket_gens(ca);
 100
 101         if (b - gens->first_bucket >= gens->nbuckets_minus_first)
 102                 return NULL;
 103         return gens->b + b;
 104 }
 105
 106 static inline int bucket_gen_get_rcu(struct bch_dev *ca, size_t b)
 107 {
 108         u8 *gen = bucket_gen(ca, b);
 109         return gen ? *gen : -1;
 110 }
 111
 112 static inline int bucket_gen_get(struct bch_dev *ca, size_t b)
 113 {
 114         rcu_read_lock();
 115         int ret = bucket_gen_get_rcu(ca, b);
 116         rcu_read_unlock();
 117         return ret;
 118 }
 119
 120 static inline size_t PTR_BUCKET_NR(const struct bch_dev *ca,
 121                                    const struct bch_extent_ptr *ptr)
 122 {
 123         return sector_to_bucket(ca, ptr->offset);
 124 }
 125
 126 static inline struct bpos PTR_BUCKET_POS(const struct bch_dev *ca,
 127                                          const struct bch_extent_ptr *ptr)
 128 {
 129         return POS(ptr->dev, PTR_BUCKET_NR(ca, ptr));
 130 }
 131
 132 static inline struct bpos PTR_BUCKET_POS_OFFSET(const struct bch_dev *ca,
 133                                                 const struct bch_extent_ptr *ptr,
 134                                                 u32 *bucket_offset)
 135 {
 136         return POS(ptr->dev, sector_to_bucket_and_offset(ca, ptr->offset, bucket_offset));
 137 }
 138
 139 static inline struct bucket *PTR_GC_BUCKET(struct bch_dev *ca,
 140                                            const struct bch_extent_ptr *ptr)
 141 {
 142         return gc_bucket(ca, PTR_BUCKET_NR(ca, ptr));
 143 }
 144
 145 static inline enum bch_data_type ptr_data_type(const struct bkey *k,
 146                                                const struct bch_extent_ptr *ptr)
 147 {
 148         if (bkey_is_btree_ptr(k))
 149                 return BCH_DATA_btree;
 150
 151         return ptr->cached ? BCH_DATA_cached : BCH_DATA_user;
 152 }
 153
 154 static inline s64 ptr_disk_sectors(s64 sectors, struct extent_ptr_decoded p)
 155 {
 156         EBUG_ON(sectors < 0);
 157
 158         return crc_is_compressed(p.crc)
 159                 ? DIV_ROUND_UP_ULL(sectors * p.crc.compressed_size,
 160                                    p.crc.uncompressed_size)
 161                 : sectors;
 162 }
 163
 164 static inline int gen_cmp(u8 a, u8 b)
 165 {
 166         return (s8) (a - b);
 167 }
 168
 169 static inline int gen_after(u8 a, u8 b)
 170 {
 171         int r = gen_cmp(a, b);
 172
 173         return r > 0 ? r : 0;
 174 }
 175
 176 static inline int dev_ptr_stale_rcu(struct bch_dev *ca, const struct bch_extent_ptr *ptr)
 177 {
 178         int gen = bucket_gen_get_rcu(ca, PTR_BUCKET_NR(ca, ptr));
 179         return gen < 0 ? gen : gen_after(gen, ptr->gen);
 180 }
 181
 182 /**
 183  * dev_ptr_stale() - check if a pointer points into a bucket that has been
 184  * invalidated.
 185  */
 186 static inline int dev_ptr_stale(struct bch_dev *ca, const struct bch_extent_ptr *ptr)
 187 {
 188         rcu_read_lock();
 189         int ret = dev_ptr_stale_rcu(ca, ptr);
 190         rcu_read_unlock();
 191         return ret;
 192 }
 193
 194 /* Device usage: */
 195
 196 void bch2_dev_usage_read_fast(struct bch_dev *, struct bch_dev_usage *);
 197 static inline struct bch_dev_usage bch2_dev_usage_read(struct bch_dev *ca)
 198 {
 199         struct bch_dev_usage ret;
 200
 201         bch2_dev_usage_read_fast(ca, &ret);
 202         return ret;
 203 }
 204
 205 void bch2_dev_usage_to_text(struct printbuf *, struct bch_dev *, struct bch_dev_usage *);
 206
 207 static inline u64 bch2_dev_buckets_reserved(struct bch_dev *ca, enum bch_watermark watermark)
 208 {
 209         s64 reserved = 0;
 210
 211         switch (watermark) {
 212         case BCH_WATERMARK_NR:
 213                 BUG();
 214         case BCH_WATERMARK_stripe:
 215                 reserved += ca->mi.nbuckets >> 6;
 216                 fallthrough;
 217         case BCH_WATERMARK_normal:
 218                 reserved += ca->mi.nbuckets >> 6;
 219                 fallthrough;
 220         case BCH_WATERMARK_copygc:
 221                 reserved += ca->nr_btree_reserve;
 222                 fallthrough;
 223         case BCH_WATERMARK_btree:
 224                 reserved += ca->nr_btree_reserve;
 225                 fallthrough;
 226         case BCH_WATERMARK_btree_copygc:
 227         case BCH_WATERMARK_reclaim:
 228         case BCH_WATERMARK_interior_updates:
 229                 break;
 230         }
 231
 232         return reserved;
 233 }
 234
 235 static inline u64 dev_buckets_free(struct bch_dev *ca,
 236                                    struct bch_dev_usage usage,
 237                                    enum bch_watermark watermark)
 238 {
 239         return max_t(s64, 0,
 240                      usage.d[BCH_DATA_free].buckets -
 241                      ca->nr_open_buckets -
 242                      bch2_dev_buckets_reserved(ca, watermark));
 243 }
 244
 245 static inline u64 __dev_buckets_available(struct bch_dev *ca,
 246                                           struct bch_dev_usage usage,
 247                                           enum bch_watermark watermark)
 248 {
 249         return max_t(s64, 0,
 250                        usage.d[BCH_DATA_free].buckets
 251                      + usage.d[BCH_DATA_cached].buckets
 252                      + usage.d[BCH_DATA_need_gc_gens].buckets
 253                      + usage.d[BCH_DATA_need_discard].buckets
 254                      - ca->nr_open_buckets
 255                      - bch2_dev_buckets_reserved(ca, watermark));
 256 }
 257
 258 static inline u64 dev_buckets_available(struct bch_dev *ca,
 259                                         enum bch_watermark watermark)
 260 {
 261         return __dev_buckets_available(ca, bch2_dev_usage_read(ca), watermark);
 262 }
 263
 264 /* Filesystem usage: */
 265
 266 static inline unsigned dev_usage_u64s(void)
 267 {
 268         return sizeof(struct bch_dev_usage) / sizeof(u64);
 269 }
 270
 271 struct bch_fs_usage_short
 272 bch2_fs_usage_read_short(struct bch_fs *);
 273
 274 int bch2_bucket_ref_update(struct btree_trans *, struct bch_dev *,
 275                            struct bkey_s_c, const struct bch_extent_ptr *,
 276                            s64, enum bch_data_type, u8, u8, u32 *);
 277
 278 int bch2_check_fix_ptrs(struct btree_trans *,
 279                         enum btree_id, unsigned, struct bkey_s_c,
 280                         enum btree_iter_update_trigger_flags);
 281
 282 int bch2_trigger_extent(struct btree_trans *, enum btree_id, unsigned,
 283                         struct bkey_s_c, struct bkey_s,
 284                         enum btree_iter_update_trigger_flags);
 285 int bch2_trigger_reservation(struct btree_trans *, enum btree_id, unsigned,
 286                           struct bkey_s_c, struct bkey_s,
 287                           enum btree_iter_update_trigger_flags);
 288
 289 #define trigger_run_overwrite_then_insert(_fn, _trans, _btree_id, _level, _old, _new, _flags)\
 290 ({                                                                                              \
 291         int ret = 0;                                                                            \
 292                                                                                                 \
 293         if (_old.k->type)                                                                       \
 294                 ret = _fn(_trans, _btree_id, _level, _old, _flags & ~BTREE_TRIGGER_insert);     \
 295         if (!ret && _new.k->type)                                                               \
 296                 ret = _fn(_trans, _btree_id, _level, _new.s_c, _flags & ~BTREE_TRIGGER_overwrite);\
 297         ret;                                                                                    \
 298 })
 299
 300 void bch2_trans_account_disk_usage_change(struct btree_trans *);
 301
 302 int bch2_trans_mark_metadata_bucket(struct btree_trans *, struct bch_dev *, u64,
 303                                     enum bch_data_type, unsigned,
 304                                     enum btree_iter_update_trigger_flags);
 305 int bch2_trans_mark_dev_sb(struct bch_fs *, struct bch_dev *,
 306                                     enum btree_iter_update_trigger_flags);
 307 int bch2_trans_mark_dev_sbs_flags(struct bch_fs *,
 308                                     enum btree_iter_update_trigger_flags);
 309 int bch2_trans_mark_dev_sbs(struct bch_fs *);
 310
 311 static inline bool is_superblock_bucket(struct bch_dev *ca, u64 b)
 312 {
 313         struct bch_sb_layout *layout = &ca->disk_sb.sb->layout;
 314         u64 b_offset    = bucket_to_sector(ca, b);
 315         u64 b_end       = bucket_to_sector(ca, b + 1);
 316         unsigned i;
 317
 318         if (!b)
 319                 return true;
 320
 321         for (i = 0; i < layout->nr_superblocks; i++) {
 322                 u64 offset = le64_to_cpu(layout->sb_offset[i]);
 323                 u64 end = offset + (1 << layout->sb_max_size_bits);
 324
 325                 if (!(offset >= b_end || end <= b_offset))
 326                         return true;
 327         }
 328
 329         return false;
 330 }
 331
 332 static inline const char *bch2_data_type_str(enum bch_data_type type)
 333 {
 334         return type < BCH_DATA_NR
 335                 ? __bch2_data_types[type]
 336                 : "(invalid data type)";
 337 }
 338
 339 /* disk reservations: */
 340
 341 static inline void bch2_disk_reservation_put(struct bch_fs *c,
 342                                              struct disk_reservation *res)
 343 {
 344         if (res->sectors) {
 345                 this_cpu_sub(*c->online_reserved, res->sectors);
 346                 res->sectors = 0;
 347         }
 348 }
 349
 350 enum bch_reservation_flags {
 351         BCH_DISK_RESERVATION_NOFAIL     = 1 << 0,
 352         BCH_DISK_RESERVATION_PARTIAL    = 1 << 1,
 353 };
 354
 355 int __bch2_disk_reservation_add(struct bch_fs *, struct disk_reservation *,
 356                                 u64, enum bch_reservation_flags);
 357
 358 static inline int bch2_disk_reservation_add(struct bch_fs *c, struct disk_reservation *res,
 359                                             u64 sectors, enum bch_reservation_flags flags)
 360 {
 361 #ifdef __KERNEL__
 362         u64 old, new;
 363
 364         old = this_cpu_read(c->pcpu->sectors_available);
 365         do {
 366                 if (sectors > old)
 367                         return __bch2_disk_reservation_add(c, res, sectors, flags);
 368
 369                 new = old - sectors;
 370         } while (!this_cpu_try_cmpxchg(c->pcpu->sectors_available, &old, new));
 371
 372         this_cpu_add(*c->online_reserved, sectors);
 373         res->sectors                    += sectors;
 374         return 0;
 375 #else
 376         return __bch2_disk_reservation_add(c, res, sectors, flags);
 377 #endif
 378 }
 379
 380 static inline struct disk_reservation
 381 bch2_disk_reservation_init(struct bch_fs *c, unsigned nr_replicas)
 382 {
 383         return (struct disk_reservation) {
 384                 .sectors        = 0,
 385 #if 0
 386                 /* not used yet: */
 387                 .gen            = c->capacity_gen,
 388 #endif
 389                 .nr_replicas    = nr_replicas,
 390         };
 391 }
 392
 393 static inline int bch2_disk_reservation_get(struct bch_fs *c,
 394                                             struct disk_reservation *res,
 395                                             u64 sectors, unsigned nr_replicas,
 396                                             int flags)
 397 {
 398         *res = bch2_disk_reservation_init(c, nr_replicas);
 399
 400         return bch2_disk_reservation_add(c, res, sectors * nr_replicas, flags);
 401 }
 402
 403 #define RESERVE_FACTOR  6
 404
 405 static inline u64 avail_factor(u64 r)
 406 {
 407         return div_u64(r << RESERVE_FACTOR, (1 << RESERVE_FACTOR) + 1);
 408 }
 409
 410 void bch2_buckets_nouse_free(struct bch_fs *);
 411 int bch2_buckets_nouse_alloc(struct bch_fs *);
 412
 413 int bch2_dev_buckets_resize(struct bch_fs *, struct bch_dev *, u64);
 414 void bch2_dev_buckets_free(struct bch_dev *);
 415 int bch2_dev_buckets_alloc(struct bch_fs *, struct bch_dev *);
 416
 417 #endif /* _BUCKETS_H */