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, lru = 0; 19 20 bkey_extent_entry_for_each(ptrs, entry) { 21 switch (__extent_entry_type(entry)) { 22 case BCH_EXTENT_ENTRY_ptr: 23 /* Might also be updating LRU btree */ 24 if (entry->ptr.cached) 25 lru++; 26 27 fallthrough; 28 case BCH_EXTENT_ENTRY_stripe_ptr: 29 ret++; 30 } 31 } 32 33 /* 34 * Updating keys in the alloc btree may also update keys in the 35 * freespace or discard btrees: 36 */ 37 return lru + ret * 2; 38 } 39 40 static int count_iters_for_insert(struct btree_trans *trans, 41 struct bkey_s_c k, 42 unsigned offset, 43 struct bpos *end, 44 unsigned *nr_iters, 45 unsigned max_iters) 46 { 47 int ret = 0, ret2 = 0; 48 49 if (*nr_iters >= max_iters) { 50 *end = bpos_min(*end, k.k->p); 51 ret = 1; 52 } 53 54 switch (k.k->type) { 55 case KEY_TYPE_extent: 56 case KEY_TYPE_reflink_v: 57 *nr_iters += bch2_bkey_nr_alloc_ptrs(k); 58 59 if (*nr_iters >= max_iters) { 60 *end = bpos_min(*end, k.k->p); 61 ret = 1; 62 } 63 64 break; 65 case KEY_TYPE_reflink_p: { 66 struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k); 67 u64 idx = le64_to_cpu(p.v->idx); 68 unsigned sectors = bpos_min(*end, p.k->p).offset - 69 bkey_start_offset(p.k); 70 struct btree_iter iter; 71 struct bkey_s_c r_k; 72 73 for_each_btree_key_norestart(trans, iter, 74 BTREE_ID_reflink, POS(0, idx + offset), 75 BTREE_ITER_SLOTS, r_k, ret2) { 76 if (bkey_ge(bkey_start_pos(r_k.k), POS(0, idx + sectors))) 77 break; 78 79 /* extent_update_to_keys(), for the reflink_v update */ 80 *nr_iters += 1; 81 82 *nr_iters += 1 + bch2_bkey_nr_alloc_ptrs(r_k); 83 84 if (*nr_iters >= max_iters) { 85 struct bpos pos = bkey_start_pos(k.k); 86 pos.offset += min_t(u64, k.k->size, 87 r_k.k->p.offset - idx); 88 89 *end = bpos_min(*end, pos); 90 ret = 1; 91 break; 92 } 93 } 94 bch2_trans_iter_exit(trans, &iter); 95 96 break; 97 } 98 } 99 100 return ret2 ?: ret; 101 } 102 103 #define EXTENT_ITERS_MAX (BTREE_ITER_INITIAL / 3) 104 105 int bch2_extent_atomic_end(struct btree_trans *trans, 106 struct btree_iter *iter, 107 struct bkey_i *insert, 108 struct bpos *end) 109 { 110 struct btree_iter copy; 111 struct bkey_s_c k; 112 unsigned nr_iters = 0; 113 int ret; 114 115 ret = bch2_btree_iter_traverse(iter); 116 if (ret) 117 return ret; 118 119 *end = insert->k.p; 120 121 /* extent_update_to_keys(): */ 122 nr_iters += 1; 123 124 ret = count_iters_for_insert(trans, bkey_i_to_s_c(insert), 0, end, 125 &nr_iters, EXTENT_ITERS_MAX / 2); 126 if (ret < 0) 127 return ret; 128 129 bch2_trans_copy_iter(©, iter); 130 131 for_each_btree_key_upto_continue_norestart(copy, insert->k.p, 0, k, ret) { 132 unsigned offset = 0; 133 134 if (bkey_gt(bkey_start_pos(&insert->k), bkey_start_pos(k.k))) 135 offset = bkey_start_offset(&insert->k) - 136 bkey_start_offset(k.k); 137 138 /* extent_handle_overwrites(): */ 139 switch (bch2_extent_overlap(&insert->k, k.k)) { 140 case BCH_EXTENT_OVERLAP_ALL: 141 case BCH_EXTENT_OVERLAP_FRONT: 142 nr_iters += 1; 143 break; 144 case BCH_EXTENT_OVERLAP_BACK: 145 case BCH_EXTENT_OVERLAP_MIDDLE: 146 nr_iters += 2; 147 break; 148 } 149 150 ret = count_iters_for_insert(trans, k, offset, end, 151 &nr_iters, EXTENT_ITERS_MAX); 152 if (ret) 153 break; 154 } 155 156 bch2_trans_iter_exit(trans, ©); 157 return ret < 0 ? ret : 0; 158 } 159 160 int bch2_extent_trim_atomic(struct btree_trans *trans, 161 struct btree_iter *iter, 162 struct bkey_i *k) 163 { 164 struct bpos end; 165 int ret; 166 167 ret = bch2_extent_atomic_end(trans, iter, k, &end); 168 if (ret) 169 return ret; 170 171 bch2_cut_back(end, k); 172 return 0; 173 } 174