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

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include "bcachefs.h"
   3 #include "btree_update.h"
   4 #include "btree_update_interior.h"
   5 #include "buckets.h"
   6 #include "debug.h"
   7 #include "extents.h"
   8 #include "extent_update.h"
   9
  10 /*
  11  * This counts the number of iterators to the alloc & ec btrees we'll need
  12  * inserting/removing this extent:
  13  */
  14 static unsigned bch2_bkey_nr_alloc_ptrs(struct bkey_s_c k)
  15 {
  16         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
  17         const union bch_extent_entry *entry;
  18         unsigned ret = 0;
  19
  20         bkey_extent_entry_for_each(ptrs, entry) {
  21                 switch (__extent_entry_type(entry)) {
  22                 case BCH_EXTENT_ENTRY_ptr:
  23                 case BCH_EXTENT_ENTRY_stripe_ptr:
  24                         ret++;
  25                 }
  26         }
  27
  28         return ret;
  29 }
  30
  31 static int count_iters_for_insert(struct btree_trans *trans,
  32                                   struct bkey_s_c k,
  33                                   unsigned offset,
  34                                   struct bpos *end,
  35                                   unsigned *nr_iters,
  36                                   unsigned max_iters)
  37 {
  38         int ret = 0, ret2 = 0;
  39
  40         if (*nr_iters >= max_iters) {
  41                 *end = bpos_min(*end, k.k->p);
  42                 ret = 1;
  43         }
  44
  45         switch (k.k->type) {
  46         case KEY_TYPE_extent:
  47         case KEY_TYPE_reflink_v:
  48                 *nr_iters += bch2_bkey_nr_alloc_ptrs(k);
  49
  50                 if (*nr_iters >= max_iters) {
  51                         *end = bpos_min(*end, k.k->p);
  52                         ret = 1;
  53                 }
  54
  55                 break;
  56         case KEY_TYPE_reflink_p: {
  57                 struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);
  58                 u64 idx = le64_to_cpu(p.v->idx);
  59                 unsigned sectors = bpos_min(*end, p.k->p).offset -
  60                         bkey_start_offset(p.k);
  61                 struct btree_iter *iter;
  62                 struct bkey_s_c r_k;
  63
  64                 for_each_btree_key(trans, iter,
  65                                    BTREE_ID_reflink, POS(0, idx + offset),
  66                                    BTREE_ITER_SLOTS, r_k, ret2) {
  67                         if (bkey_cmp(bkey_start_pos(r_k.k),
  68                                      POS(0, idx + sectors)) >= 0)
  69                                 break;
  70
  71                         /* extent_update_to_keys(), for the reflink_v update */
  72                         *nr_iters += 1;
  73
  74                         *nr_iters += 1 + bch2_bkey_nr_alloc_ptrs(r_k);
  75
  76                         if (*nr_iters >= max_iters) {
  77                                 struct bpos pos = bkey_start_pos(k.k);
  78                                 pos.offset += min_t(u64, k.k->size,
  79                                                     r_k.k->p.offset - idx);
  80
  81                                 *end = bpos_min(*end, pos);
  82                                 ret = 1;
  83                                 break;
  84                         }
  85                 }
  86
  87                 bch2_trans_iter_put(trans, iter);
  88                 break;
  89         }
  90         }
  91
  92         return ret2 ?: ret;
  93 }
  94
  95 #define EXTENT_ITERS_MAX        (BTREE_ITER_MAX / 3)
  96
  97 int bch2_extent_atomic_end(struct btree_iter *iter,
  98                            struct bkey_i *insert,
  99                            struct bpos *end)
 100 {
 101         struct btree_trans *trans = iter->trans;
 102         struct btree_iter *copy;
 103         struct bkey_s_c k;
 104         unsigned nr_iters = 0;
 105         int ret;
 106
 107         ret = bch2_btree_iter_traverse(iter);
 108         if (ret)
 109                 return ret;
 110
 111         *end = insert->k.p;
 112
 113         /* extent_update_to_keys(): */
 114         nr_iters += 1;
 115
 116         ret = count_iters_for_insert(trans, bkey_i_to_s_c(insert), 0, end,
 117                                      &nr_iters, EXTENT_ITERS_MAX / 2);
 118         if (ret < 0)
 119                 return ret;
 120
 121         copy = bch2_trans_copy_iter(trans, iter);
 122
 123         for_each_btree_key_continue(copy, 0, k, ret) {
 124                 unsigned offset = 0;
 125
 126                 if (bkey_cmp(bkey_start_pos(k.k), *end) >= 0)
 127                         break;
 128
 129                 if (bkey_cmp(bkey_start_pos(&insert->k),
 130                              bkey_start_pos(k.k)) > 0)
 131                         offset = bkey_start_offset(&insert->k) -
 132                                 bkey_start_offset(k.k);
 133
 134                 /* extent_handle_overwrites(): */
 135                 switch (bch2_extent_overlap(&insert->k, k.k)) {
 136                 case BCH_EXTENT_OVERLAP_ALL:
 137                 case BCH_EXTENT_OVERLAP_FRONT:
 138                         nr_iters += 1;
 139                         break;
 140                 case BCH_EXTENT_OVERLAP_BACK:
 141                 case BCH_EXTENT_OVERLAP_MIDDLE:
 142                         nr_iters += 2;
 143                         break;
 144                 }
 145
 146                 ret = count_iters_for_insert(trans, k, offset, end,
 147                                         &nr_iters, EXTENT_ITERS_MAX);
 148                 if (ret)
 149                         break;
 150         }
 151
 152         bch2_trans_iter_put(trans, copy);
 153         return ret < 0 ? ret : 0;
 154 }
 155
 156 int bch2_extent_trim_atomic(struct bkey_i *k, struct btree_iter *iter)
 157 {
 158         struct bpos end;
 159         int ret;
 160
 161         ret = bch2_extent_atomic_end(iter, k, &end);
 162         if (ret)
 163                 return ret;
 164
 165         bch2_cut_back(end, k);
 166         return 0;
 167 }
 168
 169 int bch2_extent_is_atomic(struct bkey_i *k, struct btree_iter *iter)
 170 {
 171         struct bpos end;
 172         int ret;
 173
 174         ret = bch2_extent_atomic_end(iter, k, &end);
 175         if (ret)
 176                 return ret;
 177
 178         return !bkey_cmp(end, k->k.p);
 179 }