git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/reflink.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 "extents.h"
   6 #include "inode.h"
   7 #include "io.h"
   8 #include "reflink.h"
   9
  10 #include <linux/sched/signal.h>
  11
  12 static inline unsigned bkey_type_to_indirect(const struct bkey *k)
  13 {
  14         switch (k->type) {
  15         case KEY_TYPE_extent:
  16                 return KEY_TYPE_reflink_v;
  17         case KEY_TYPE_inline_data:
  18                 return KEY_TYPE_indirect_inline_data;
  19         default:
  20                 return 0;
  21         }
  22 }
  23
  24 /* reflink pointers */
  25
  26 const char *bch2_reflink_p_invalid(const struct bch_fs *c, struct bkey_s_c k)
  27 {
  28         struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);
  29
  30         if (bkey_val_bytes(p.k) != sizeof(*p.v))
  31                 return "incorrect value size";
  32
  33         return NULL;
  34 }
  35
  36 void bch2_reflink_p_to_text(struct printbuf *out, struct bch_fs *c,
  37                             struct bkey_s_c k)
  38 {
  39         struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);
  40
  41         pr_buf(out, "idx %llu", le64_to_cpu(p.v->idx));
  42 }
  43
  44 enum merge_result bch2_reflink_p_merge(struct bch_fs *c,
  45                                        struct bkey_s _l, struct bkey_s _r)
  46 {
  47         struct bkey_s_reflink_p l = bkey_s_to_reflink_p(_l);
  48         struct bkey_s_reflink_p r = bkey_s_to_reflink_p(_r);
  49
  50         if (le64_to_cpu(l.v->idx) + l.k->size != le64_to_cpu(r.v->idx))
  51                 return BCH_MERGE_NOMERGE;
  52
  53         if ((u64) l.k->size + r.k->size > KEY_SIZE_MAX) {
  54                 bch2_key_resize(l.k, KEY_SIZE_MAX);
  55                 bch2_cut_front_s(l.k->p, _r);
  56                 return BCH_MERGE_PARTIAL;
  57         }
  58
  59         bch2_key_resize(l.k, l.k->size + r.k->size);
  60
  61         return BCH_MERGE_MERGE;
  62 }
  63
  64 /* indirect extents */
  65
  66 const char *bch2_reflink_v_invalid(const struct bch_fs *c, struct bkey_s_c k)
  67 {
  68         struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(k);
  69
  70         if (bkey_val_bytes(r.k) < sizeof(*r.v))
  71                 return "incorrect value size";
  72
  73         return bch2_bkey_ptrs_invalid(c, k);
  74 }
  75
  76 void bch2_reflink_v_to_text(struct printbuf *out, struct bch_fs *c,
  77                             struct bkey_s_c k)
  78 {
  79         struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(k);
  80
  81         pr_buf(out, "refcount: %llu ", le64_to_cpu(r.v->refcount));
  82
  83         bch2_bkey_ptrs_to_text(out, c, k);
  84 }
  85
  86 /* indirect inline data */
  87
  88 const char *bch2_indirect_inline_data_invalid(const struct bch_fs *c,
  89                                               struct bkey_s_c k)
  90 {
  91         if (bkey_val_bytes(k.k) < sizeof(struct bch_indirect_inline_data))
  92                 return "incorrect value size";
  93         return NULL;
  94 }
  95
  96 void bch2_indirect_inline_data_to_text(struct printbuf *out,
  97                                         struct bch_fs *c, struct bkey_s_c k)
  98 {
  99         struct bkey_s_c_indirect_inline_data d = bkey_s_c_to_indirect_inline_data(k);
 100         unsigned datalen = bkey_inline_data_bytes(k.k);
 101
 102         pr_buf(out, "refcount %llu datalen %u: %*phN",
 103                le64_to_cpu(d.v->refcount), datalen,
 104                min(datalen, 32U), d.v->data);
 105 }
 106
 107 static int bch2_make_extent_indirect(struct btree_trans *trans,
 108                                      struct btree_iter *extent_iter,
 109                                      struct bkey_i *orig)
 110 {
 111         struct bch_fs *c = trans->c;
 112         struct btree_iter *reflink_iter;
 113         struct bkey_s_c k;
 114         struct bkey_i *r_v;
 115         struct bkey_i_reflink_p *r_p;
 116         __le64 *refcount;
 117         int ret;
 118
 119         if (orig->k.type == KEY_TYPE_inline_data)
 120                 bch2_check_set_feature(c, BCH_FEATURE_reflink_inline_data);
 121
 122         for_each_btree_key(trans, reflink_iter, BTREE_ID_REFLINK,
 123                            POS(0, c->reflink_hint),
 124                            BTREE_ITER_INTENT|BTREE_ITER_SLOTS, k, ret) {
 125                 if (reflink_iter->pos.inode) {
 126                         bch2_btree_iter_set_pos(reflink_iter, POS_MIN);
 127                         continue;
 128                 }
 129
 130                 if (bkey_deleted(k.k) && orig->k.size <= k.k->size)
 131                         break;
 132         }
 133
 134         if (ret)
 135                 goto err;
 136
 137         /* rewind iter to start of hole, if necessary: */
 138         bch2_btree_iter_set_pos(reflink_iter, bkey_start_pos(k.k));
 139
 140         r_v = bch2_trans_kmalloc(trans, sizeof(__le64) + bkey_val_bytes(&orig->k));
 141         ret = PTR_ERR_OR_ZERO(r_v);
 142         if (ret)
 143                 goto err;
 144
 145         bkey_init(&r_v->k);
 146         r_v->k.type     = bkey_type_to_indirect(&orig->k);
 147         r_v->k.p        = reflink_iter->pos;
 148         bch2_key_resize(&r_v->k, orig->k.size);
 149         r_v->k.version  = orig->k.version;
 150
 151         set_bkey_val_bytes(&r_v->k, sizeof(__le64) + bkey_val_bytes(&orig->k));
 152
 153         refcount        = (void *) &r_v->v;
 154         *refcount       = 0;
 155         memcpy(refcount + 1, &orig->v, bkey_val_bytes(&orig->k));
 156
 157         bch2_trans_update(trans, reflink_iter, r_v, 0);
 158
 159         r_p = bch2_trans_kmalloc(trans, sizeof(*r_p));
 160         if (IS_ERR(r_p))
 161                 return PTR_ERR(r_p);
 162
 163         orig->k.type = KEY_TYPE_reflink_p;
 164         r_p = bkey_i_to_reflink_p(orig);
 165         set_bkey_val_bytes(&r_p->k, sizeof(r_p->v));
 166         r_p->v.idx = cpu_to_le64(bkey_start_offset(&r_v->k));
 167
 168         bch2_trans_update(trans, extent_iter, &r_p->k_i, 0);
 169 err:
 170         if (!IS_ERR(reflink_iter))
 171                 c->reflink_hint = reflink_iter->pos.offset;
 172         bch2_trans_iter_put(trans, reflink_iter);
 173
 174         return ret;
 175 }
 176
 177 static struct bkey_s_c get_next_src(struct btree_iter *iter, struct bpos end)
 178 {
 179         struct bkey_s_c k = bch2_btree_iter_peek(iter);
 180         int ret;
 181
 182         for_each_btree_key_continue(iter, 0, k, ret) {
 183                 if (bkey_cmp(iter->pos, end) >= 0)
 184                         return bkey_s_c_null;
 185
 186                 if (bkey_extent_is_data(k.k))
 187                         break;
 188         }
 189
 190         return k;
 191 }
 192
 193 s64 bch2_remap_range(struct bch_fs *c,
 194                      struct bpos dst_start, struct bpos src_start,
 195                      u64 remap_sectors, u64 *journal_seq,
 196                      u64 new_i_size, s64 *i_sectors_delta)
 197 {
 198         struct btree_trans trans;
 199         struct btree_iter *dst_iter, *src_iter;
 200         struct bkey_s_c src_k;
 201         BKEY_PADDED(k) new_dst;
 202         struct bkey_on_stack new_src;
 203         struct bpos dst_end = dst_start, src_end = src_start;
 204         struct bpos dst_want, src_want;
 205         u64 src_done, dst_done;
 206         int ret = 0, ret2 = 0;
 207
 208         if (!c->opts.reflink)
 209                 return -EOPNOTSUPP;
 210
 211         if (!percpu_ref_tryget(&c->writes))
 212                 return -EROFS;
 213
 214         bch2_check_set_feature(c, BCH_FEATURE_reflink);
 215
 216         dst_end.offset += remap_sectors;
 217         src_end.offset += remap_sectors;
 218
 219         bkey_on_stack_init(&new_src);
 220         bch2_trans_init(&trans, c, BTREE_ITER_MAX, 4096);
 221
 222         src_iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS, src_start,
 223                                        BTREE_ITER_INTENT);
 224         dst_iter = bch2_trans_get_iter(&trans, BTREE_ID_EXTENTS, dst_start,
 225                                        BTREE_ITER_INTENT);
 226
 227         while (1) {
 228                 bch2_trans_begin(&trans);
 229
 230                 trans.mem_top = 0;
 231
 232                 if (fatal_signal_pending(current)) {
 233                         ret = -EINTR;
 234                         goto err;
 235                 }
 236
 237                 src_k = get_next_src(src_iter, src_end);
 238                 ret = bkey_err(src_k);
 239                 if (ret)
 240                         goto btree_err;
 241
 242                 src_done = bpos_min(src_iter->pos, src_end).offset -
 243                         src_start.offset;
 244                 dst_want = POS(dst_start.inode, dst_start.offset + src_done);
 245
 246                 if (bkey_cmp(dst_iter->pos, dst_want) < 0) {
 247                         ret = bch2_fpunch_at(&trans, dst_iter, dst_want,
 248                                              journal_seq, i_sectors_delta);
 249                         if (ret)
 250                                 goto btree_err;
 251                         continue;
 252                 }
 253
 254                 BUG_ON(bkey_cmp(dst_iter->pos, dst_want));
 255
 256                 if (!bkey_cmp(dst_iter->pos, dst_end))
 257                         break;
 258
 259                 if (src_k.k->type != KEY_TYPE_reflink_p) {
 260                         bkey_on_stack_reassemble(&new_src, c, src_k);
 261                         src_k = bkey_i_to_s_c(new_src.k);
 262
 263                         bch2_cut_front(src_iter->pos,   new_src.k);
 264                         bch2_cut_back(src_end,          new_src.k);
 265
 266                         ret = bch2_make_extent_indirect(&trans, src_iter,
 267                                                 new_src.k);
 268                         if (ret)
 269                                 goto btree_err;
 270
 271                         BUG_ON(src_k.k->type != KEY_TYPE_reflink_p);
 272                 }
 273
 274                 if (src_k.k->type == KEY_TYPE_reflink_p) {
 275                         struct bkey_s_c_reflink_p src_p =
 276                                 bkey_s_c_to_reflink_p(src_k);
 277                         struct bkey_i_reflink_p *dst_p =
 278                                 bkey_reflink_p_init(&new_dst.k);
 279
 280                         u64 offset = le64_to_cpu(src_p.v->idx) +
 281                                 (src_iter->pos.offset -
 282                                  bkey_start_offset(src_k.k));
 283
 284                         dst_p->v.idx = cpu_to_le64(offset);
 285                 } else {
 286                         BUG();
 287                 }
 288
 289                 new_dst.k.k.p = dst_iter->pos;
 290                 bch2_key_resize(&new_dst.k.k,
 291                                 min(src_k.k->p.offset - src_iter->pos.offset,
 292                                     dst_end.offset - dst_iter->pos.offset));
 293
 294                 ret = bch2_extent_update(&trans, dst_iter, &new_dst.k,
 295                                          NULL, journal_seq,
 296                                          new_i_size, i_sectors_delta);
 297                 if (ret)
 298                         goto btree_err;
 299
 300                 dst_done = dst_iter->pos.offset - dst_start.offset;
 301                 src_want = POS(src_start.inode, src_start.offset + dst_done);
 302                 bch2_btree_iter_set_pos(src_iter, src_want);
 303 btree_err:
 304                 if (ret == -EINTR)
 305                         ret = 0;
 306                 if (ret)
 307                         goto err;
 308         }
 309
 310         BUG_ON(bkey_cmp(dst_iter->pos, dst_end));
 311 err:
 312         BUG_ON(bkey_cmp(dst_iter->pos, dst_end) > 0);
 313
 314         dst_done = dst_iter->pos.offset - dst_start.offset;
 315         new_i_size = min(dst_iter->pos.offset << 9, new_i_size);
 316
 317         bch2_trans_begin(&trans);
 318
 319         do {
 320                 struct bch_inode_unpacked inode_u;
 321                 struct btree_iter *inode_iter;
 322
 323                 inode_iter = bch2_inode_peek(&trans, &inode_u,
 324                                 dst_start.inode, BTREE_ITER_INTENT);
 325                 ret2 = PTR_ERR_OR_ZERO(inode_iter);
 326
 327                 if (!ret2 &&
 328                     inode_u.bi_size < new_i_size) {
 329                         inode_u.bi_size = new_i_size;
 330                         ret2  = bch2_inode_write(&trans, inode_iter, &inode_u) ?:
 331                                 bch2_trans_commit(&trans, NULL, journal_seq, 0);
 332                 }
 333         } while (ret2 == -EINTR);
 334
 335         ret = bch2_trans_exit(&trans) ?: ret;
 336         bkey_on_stack_exit(&new_src, c);
 337
 338         percpu_ref_put(&c->writes);
 339
 340         return dst_done ?: ret ?: ret2;
 341 }