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 "bkey_on_stack.h"
   4 #include "btree_update.h"
   5 #include "btree_update_interior.h"
   6 #include "buckets.h"
   7 #include "debug.h"
   8 #include "extents.h"
   9 #include "extent_update.h"
  10
  11 /*
  12  * This counts the number of iterators to the alloc & ec btrees we'll need
  13  * inserting/removing this extent:
  14  */
  15 static unsigned bch2_bkey_nr_alloc_ptrs(struct bkey_s_c k)
  16 {
  17         struct bkey_ptrs_c ptrs = bch2_bkey_ptrs_c(k);
  18         const union bch_extent_entry *entry;
  19         unsigned ret = 0;
  20
  21         bkey_extent_entry_for_each(ptrs, entry) {
  22                 switch (__extent_entry_type(entry)) {
  23                 case BCH_EXTENT_ENTRY_ptr:
  24                 case BCH_EXTENT_ENTRY_stripe_ptr:
  25                         ret++;
  26                 }
  27         }
  28
  29         return ret;
  30 }
  31
  32 static int count_iters_for_insert(struct btree_trans *trans,
  33                                   struct bkey_s_c k,
  34                                   unsigned offset,
  35                                   struct bpos *end,
  36                                   unsigned *nr_iters,
  37                                   unsigned max_iters)
  38 {
  39         int ret = 0, ret2 = 0;
  40
  41         if (*nr_iters >= max_iters) {
  42                 *end = bpos_min(*end, k.k->p);
  43                 ret = 1;
  44         }
  45
  46         switch (k.k->type) {
  47         case KEY_TYPE_extent:
  48         case KEY_TYPE_reflink_v:
  49                 *nr_iters += bch2_bkey_nr_alloc_ptrs(k);
  50
  51                 if (*nr_iters >= max_iters) {
  52                         *end = bpos_min(*end, k.k->p);
  53                         ret = 1;
  54                 }
  55
  56                 break;
  57         case KEY_TYPE_reflink_p: {
  58                 struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);
  59                 u64 idx = le64_to_cpu(p.v->idx);
  60                 unsigned sectors = bpos_min(*end, p.k->p).offset -
  61                         bkey_start_offset(p.k);
  62                 struct btree_iter *iter;
  63                 struct bkey_s_c r_k;
  64
  65                 for_each_btree_key(trans, iter,
  66                                    BTREE_ID_REFLINK, POS(0, idx + offset),
  67                                    BTREE_ITER_SLOTS, r_k, ret2) {
  68                         if (bkey_cmp(bkey_start_pos(r_k.k),
  69                                      POS(0, idx + sectors)) >= 0)
  70                                 break;
  71
  72                         /* extent_update_to_keys(), for the reflink_v update */
  73                         *nr_iters += 1;
  74
  75                         *nr_iters += 1 + bch2_bkey_nr_alloc_ptrs(r_k);
  76
  77                         if (*nr_iters >= max_iters) {
  78                                 struct bpos pos = bkey_start_pos(k.k);
  79                                 pos.offset += min_t(u64, k.k->size,
  80                                                     r_k.k->p.offset - idx);
  81
  82                                 *end = bpos_min(*end, pos);
  83                                 ret = 1;
  84                                 break;
  85                         }
  86                 }
  87
  88                 bch2_trans_iter_put(trans, iter);
  89                 break;
  90         }
  91         }
  92
  93         return ret2 ?: ret;
  94 }
  95
  96 #define EXTENT_ITERS_MAX        (BTREE_ITER_MAX / 3)
  97
  98 int bch2_extent_atomic_end(struct btree_iter *iter,
  99                            struct bkey_i *insert,
 100                            struct bpos *end)
 101 {
 102         struct btree_trans *trans = iter->trans;
 103         struct btree *b;
 104         struct btree_node_iter  node_iter;
 105         struct bkey_packed      *_k;
 106         unsigned                nr_iters = 0;
 107         int ret;
 108
 109         ret = bch2_btree_iter_traverse(iter);
 110         if (ret)
 111                 return ret;
 112
 113         b = iter->l[0].b;
 114         node_iter = iter->l[0].iter;
 115
 116         BUG_ON(bkey_cmp(b->data->min_key, POS_MIN) &&
 117                bkey_cmp(bkey_start_pos(&insert->k),
 118                         bkey_predecessor(b->data->min_key)) < 0);
 119
 120         *end = bpos_min(insert->k.p, b->key.k.p);
 121
 122         /* extent_update_to_keys(): */
 123         nr_iters += 1;
 124
 125         ret = count_iters_for_insert(trans, bkey_i_to_s_c(insert), 0, end,
 126                                      &nr_iters, EXTENT_ITERS_MAX / 2);
 127         if (ret < 0)
 128                 return ret;
 129
 130         while ((_k = bch2_btree_node_iter_peek(&node_iter, b))) {
 131                 struct bkey     unpacked;
 132                 struct bkey_s_c k = bkey_disassemble(b, _k, &unpacked);
 133                 unsigned offset = 0;
 134
 135                 if (bkey_cmp(bkey_start_pos(k.k), *end) >= 0)
 136                         break;
 137
 138                 if (bkey_cmp(bkey_start_pos(&insert->k),
 139                              bkey_start_pos(k.k)) > 0)
 140                         offset = bkey_start_offset(&insert->k) -
 141                                 bkey_start_offset(k.k);
 142
 143                 /* extent_handle_overwrites(): */
 144                 switch (bch2_extent_overlap(&insert->k, k.k)) {
 145                 case BCH_EXTENT_OVERLAP_ALL:
 146                 case BCH_EXTENT_OVERLAP_FRONT:
 147                         nr_iters += 1;
 148                         break;
 149                 case BCH_EXTENT_OVERLAP_BACK:
 150                 case BCH_EXTENT_OVERLAP_MIDDLE:
 151                         nr_iters += 2;
 152                         break;
 153                 }
 154
 155                 ret = count_iters_for_insert(trans, k, offset, end,
 156                                         &nr_iters, EXTENT_ITERS_MAX);
 157                 if (ret)
 158                         break;
 159
 160                 bch2_btree_node_iter_advance(&node_iter, b);
 161         }
 162
 163         return ret < 0 ? ret : 0;
 164 }
 165
 166 int bch2_extent_trim_atomic(struct bkey_i *k, struct btree_iter *iter)
 167 {
 168         struct bpos end;
 169         int ret;
 170
 171         ret = bch2_extent_atomic_end(iter, k, &end);
 172         if (ret)
 173                 return ret;
 174
 175         bch2_cut_back(end, k);
 176         return 0;
 177 }
 178
 179 int bch2_extent_is_atomic(struct bkey_i *k, struct btree_iter *iter)
 180 {
 181         struct bpos end;
 182         int ret;
 183
 184         ret = bch2_extent_atomic_end(iter, k, &end);
 185         if (ret)
 186                 return ret;
 187
 188         return !bkey_cmp(end, k->k.p);
 189 }
 190
 191 enum btree_insert_ret
 192 bch2_extent_can_insert(struct btree_trans *trans,
 193                        struct btree_iter *iter,
 194                        struct bkey_i *insert)
 195 {
 196         struct btree_iter_level *l = &iter->l[0];
 197         struct btree_node_iter node_iter = l->iter;
 198         struct bkey_packed *_k;
 199         struct bkey_s_c k;
 200         struct bkey unpacked;
 201         int sectors;
 202
 203         _k = bch2_btree_node_iter_peek(&node_iter, l->b);
 204         if (!_k)
 205                 return BTREE_INSERT_OK;
 206
 207         k = bkey_disassemble(l->b, _k, &unpacked);
 208
 209         /* Check if we're splitting a compressed extent: */
 210
 211         if (bkey_cmp(bkey_start_pos(&insert->k), bkey_start_pos(k.k)) > 0 &&
 212             bkey_cmp(insert->k.p, k.k->p) < 0 &&
 213             (sectors = bch2_bkey_sectors_compressed(k))) {
 214                 int flags = trans->flags & BTREE_INSERT_NOFAIL
 215                         ? BCH_DISK_RESERVATION_NOFAIL : 0;
 216
 217                 switch (bch2_disk_reservation_add(trans->c, trans->disk_res,
 218                                                   sectors, flags)) {
 219                 case 0:
 220                         break;
 221                 case -ENOSPC:
 222                         return BTREE_INSERT_ENOSPC;
 223                 default:
 224                         BUG();
 225                 }
 226         }
 227
 228         return BTREE_INSERT_OK;
 229 }