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_buf.h"
   4 #include "btree_update.h"
   5 #include "buckets.h"
   6 #include "extents.h"
   7 #include "inode.h"
   8 #include "io_misc.h"
   9 #include "io_write.h"
  10 #include "rebalance.h"
  11 #include "reflink.h"
  12 #include "subvolume.h"
  13 #include "super-io.h"
  14
  15 #include <linux/sched/signal.h>
  16
  17 static inline unsigned bkey_type_to_indirect(const struct bkey *k)
  18 {
  19         switch (k->type) {
  20         case KEY_TYPE_extent:
  21                 return KEY_TYPE_reflink_v;
  22         case KEY_TYPE_inline_data:
  23                 return KEY_TYPE_indirect_inline_data;
  24         default:
  25                 return 0;
  26         }
  27 }
  28
  29 /* reflink pointers */
  30
  31 int bch2_reflink_p_invalid(struct bch_fs *c, struct bkey_s_c k,
  32                            enum bkey_invalid_flags flags,
  33                            struct printbuf *err)
  34 {
  35         struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);
  36
  37         if (c->sb.version >= bcachefs_metadata_version_reflink_p_fix &&
  38             le64_to_cpu(p.v->idx) < le32_to_cpu(p.v->front_pad)) {
  39                 prt_printf(err, "idx < front_pad (%llu < %u)",
  40                        le64_to_cpu(p.v->idx), le32_to_cpu(p.v->front_pad));
  41                 return -EINVAL;
  42         }
  43
  44         return 0;
  45 }
  46
  47 void bch2_reflink_p_to_text(struct printbuf *out, struct bch_fs *c,
  48                             struct bkey_s_c k)
  49 {
  50         struct bkey_s_c_reflink_p p = bkey_s_c_to_reflink_p(k);
  51
  52         prt_printf(out, "idx %llu front_pad %u back_pad %u",
  53                le64_to_cpu(p.v->idx),
  54                le32_to_cpu(p.v->front_pad),
  55                le32_to_cpu(p.v->back_pad));
  56 }
  57
  58 bool bch2_reflink_p_merge(struct bch_fs *c, struct bkey_s _l, struct bkey_s_c _r)
  59 {
  60         struct bkey_s_reflink_p l = bkey_s_to_reflink_p(_l);
  61         struct bkey_s_c_reflink_p r = bkey_s_c_to_reflink_p(_r);
  62
  63         /*
  64          * Disabled for now, the triggers code needs to be reworked for merging
  65          * of reflink pointers to work:
  66          */
  67         return false;
  68
  69         if (le64_to_cpu(l.v->idx) + l.k->size != le64_to_cpu(r.v->idx))
  70                 return false;
  71
  72         bch2_key_resize(l.k, l.k->size + r.k->size);
  73         return true;
  74 }
  75
  76 /* indirect extents */
  77
  78 int bch2_reflink_v_invalid(struct bch_fs *c, struct bkey_s_c k,
  79                            enum bkey_invalid_flags flags,
  80                            struct printbuf *err)
  81 {
  82         return bch2_bkey_ptrs_invalid(c, k, flags, err);
  83 }
  84
  85 void bch2_reflink_v_to_text(struct printbuf *out, struct bch_fs *c,
  86                             struct bkey_s_c k)
  87 {
  88         struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(k);
  89
  90         prt_printf(out, "refcount: %llu ", le64_to_cpu(r.v->refcount));
  91
  92         bch2_bkey_ptrs_to_text(out, c, k);
  93 }
  94
  95 #if 0
  96 Currently disabled, needs to be debugged:
  97
  98 bool bch2_reflink_v_merge(struct bch_fs *c, struct bkey_s _l, struct bkey_s_c _r)
  99 {
 100         struct bkey_s_reflink_v   l = bkey_s_to_reflink_v(_l);
 101         struct bkey_s_c_reflink_v r = bkey_s_c_to_reflink_v(_r);
 102
 103         return l.v->refcount == r.v->refcount && bch2_extent_merge(c, _l, _r);
 104 }
 105 #endif
 106
 107 static inline void check_indirect_extent_deleting(struct bkey_i *new, unsigned *flags)
 108 {
 109         if ((*flags & BTREE_TRIGGER_INSERT) && !*bkey_refcount(new)) {
 110                 new->k.type = KEY_TYPE_deleted;
 111                 new->k.size = 0;
 112                 set_bkey_val_u64s(&new->k, 0);;
 113                 *flags &= ~BTREE_TRIGGER_INSERT;
 114         }
 115 }
 116
 117 int bch2_trans_mark_reflink_v(struct btree_trans *trans,
 118                               enum btree_id btree_id, unsigned level,
 119                               struct bkey_s_c old, struct bkey_i *new,
 120                               unsigned flags)
 121 {
 122         check_indirect_extent_deleting(new, &flags);
 123
 124         return bch2_trans_mark_extent(trans, btree_id, level, old, new, flags);
 125 }
 126
 127 /* indirect inline data */
 128
 129 int bch2_indirect_inline_data_invalid(struct bch_fs *c, struct bkey_s_c k,
 130                                       enum bkey_invalid_flags flags,
 131                                       struct printbuf *err)
 132 {
 133         return 0;
 134 }
 135
 136 void bch2_indirect_inline_data_to_text(struct printbuf *out,
 137                                        struct bch_fs *c, struct bkey_s_c k)
 138 {
 139         struct bkey_s_c_indirect_inline_data d = bkey_s_c_to_indirect_inline_data(k);
 140         unsigned datalen = bkey_inline_data_bytes(k.k);
 141
 142         prt_printf(out, "refcount %llu datalen %u: %*phN",
 143                le64_to_cpu(d.v->refcount), datalen,
 144                min(datalen, 32U), d.v->data);
 145 }
 146
 147 int bch2_trans_mark_indirect_inline_data(struct btree_trans *trans,
 148                               enum btree_id btree_id, unsigned level,
 149                               struct bkey_s_c old, struct bkey_i *new,
 150                               unsigned flags)
 151 {
 152         check_indirect_extent_deleting(new, &flags);
 153
 154         return 0;
 155 }
 156
 157 static int bch2_make_extent_indirect(struct btree_trans *trans,
 158                                      struct btree_iter *extent_iter,
 159                                      struct bkey_i *orig)
 160 {
 161         struct bch_fs *c = trans->c;
 162         struct btree_iter reflink_iter = { NULL };
 163         struct bkey_s_c k;
 164         struct bkey_i *r_v;
 165         struct bkey_i_reflink_p *r_p;
 166         __le64 *refcount;
 167         int ret;
 168
 169         if (orig->k.type == KEY_TYPE_inline_data)
 170                 bch2_check_set_feature(c, BCH_FEATURE_reflink_inline_data);
 171
 172         bch2_trans_iter_init(trans, &reflink_iter, BTREE_ID_reflink, POS_MAX,
 173                              BTREE_ITER_INTENT);
 174         k = bch2_btree_iter_peek_prev(&reflink_iter);
 175         ret = bkey_err(k);
 176         if (ret)
 177                 goto err;
 178
 179         r_v = bch2_trans_kmalloc(trans, sizeof(__le64) + bkey_bytes(&orig->k));
 180         ret = PTR_ERR_OR_ZERO(r_v);
 181         if (ret)
 182                 goto err;
 183
 184         bkey_init(&r_v->k);
 185         r_v->k.type     = bkey_type_to_indirect(&orig->k);
 186         r_v->k.p        = reflink_iter.pos;
 187         bch2_key_resize(&r_v->k, orig->k.size);
 188         r_v->k.version  = orig->k.version;
 189
 190         set_bkey_val_bytes(&r_v->k, sizeof(__le64) + bkey_val_bytes(&orig->k));
 191
 192         refcount        = bkey_refcount(r_v);
 193         *refcount       = 0;
 194         memcpy(refcount + 1, &orig->v, bkey_val_bytes(&orig->k));
 195
 196         ret = bch2_trans_update(trans, &reflink_iter, r_v, 0);
 197         if (ret)
 198                 goto err;
 199
 200         /*
 201          * orig is in a bkey_buf which statically allocates 5 64s for the val,
 202          * so we know it will be big enough:
 203          */
 204         orig->k.type = KEY_TYPE_reflink_p;
 205         r_p = bkey_i_to_reflink_p(orig);
 206         set_bkey_val_bytes(&r_p->k, sizeof(r_p->v));
 207
 208         /* FORTIFY_SOURCE is broken here, and doesn't provide unsafe_memset() */
 209 #if !defined(__NO_FORTIFY) && defined(__OPTIMIZE__) && defined(CONFIG_FORTIFY_SOURCE)
 210         __underlying_memset(&r_p->v, 0, sizeof(r_p->v));
 211 #else
 212         memset(&r_p->v, 0, sizeof(r_p->v));
 213 #endif
 214
 215         r_p->v.idx = cpu_to_le64(bkey_start_offset(&r_v->k));
 216
 217         ret = bch2_trans_update(trans, extent_iter, &r_p->k_i,
 218                                 BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE);
 219 err:
 220         bch2_trans_iter_exit(trans, &reflink_iter);
 221
 222         return ret;
 223 }
 224
 225 static struct bkey_s_c get_next_src(struct btree_iter *iter, struct bpos end)
 226 {
 227         struct bkey_s_c k;
 228         int ret;
 229
 230         for_each_btree_key_upto_continue_norestart(*iter, end, 0, k, ret) {
 231                 if (bkey_extent_is_unwritten(k))
 232                         continue;
 233
 234                 if (bkey_extent_is_data(k.k))
 235                         return k;
 236         }
 237
 238         if (bkey_ge(iter->pos, end))
 239                 bch2_btree_iter_set_pos(iter, end);
 240         return ret ? bkey_s_c_err(ret) : bkey_s_c_null;
 241 }
 242
 243 s64 bch2_remap_range(struct bch_fs *c,
 244                      subvol_inum dst_inum, u64 dst_offset,
 245                      subvol_inum src_inum, u64 src_offset,
 246                      u64 remap_sectors,
 247                      u64 new_i_size, s64 *i_sectors_delta)
 248 {
 249         struct btree_trans *trans;
 250         struct btree_iter dst_iter, src_iter;
 251         struct bkey_s_c src_k;
 252         struct bkey_buf new_dst, new_src;
 253         struct bpos dst_start = POS(dst_inum.inum, dst_offset);
 254         struct bpos src_start = POS(src_inum.inum, src_offset);
 255         struct bpos dst_end = dst_start, src_end = src_start;
 256         struct bch_io_opts opts;
 257         struct bpos src_want;
 258         u64 dst_done = 0;
 259         u32 dst_snapshot, src_snapshot;
 260         int ret = 0, ret2 = 0;
 261
 262         if (!bch2_write_ref_tryget(c, BCH_WRITE_REF_reflink))
 263                 return -BCH_ERR_erofs_no_writes;
 264
 265         bch2_check_set_feature(c, BCH_FEATURE_reflink);
 266
 267         dst_end.offset += remap_sectors;
 268         src_end.offset += remap_sectors;
 269
 270         bch2_bkey_buf_init(&new_dst);
 271         bch2_bkey_buf_init(&new_src);
 272         trans = bch2_trans_get(c);
 273
 274         ret = bch2_inum_opts_get(trans, src_inum, &opts);
 275         if (ret)
 276                 goto err;
 277
 278         bch2_trans_iter_init(trans, &src_iter, BTREE_ID_extents, src_start,
 279                              BTREE_ITER_INTENT);
 280         bch2_trans_iter_init(trans, &dst_iter, BTREE_ID_extents, dst_start,
 281                              BTREE_ITER_INTENT);
 282
 283         while ((ret == 0 ||
 284                 bch2_err_matches(ret, BCH_ERR_transaction_restart)) &&
 285                bkey_lt(dst_iter.pos, dst_end)) {
 286                 struct disk_reservation disk_res = { 0 };
 287
 288                 bch2_trans_begin(trans);
 289
 290                 if (fatal_signal_pending(current)) {
 291                         ret = -EINTR;
 292                         break;
 293                 }
 294
 295                 ret = bch2_subvolume_get_snapshot(trans, src_inum.subvol,
 296                                                   &src_snapshot);
 297                 if (ret)
 298                         continue;
 299
 300                 bch2_btree_iter_set_snapshot(&src_iter, src_snapshot);
 301
 302                 ret = bch2_subvolume_get_snapshot(trans, dst_inum.subvol,
 303                                                   &dst_snapshot);
 304                 if (ret)
 305                         continue;
 306
 307                 bch2_btree_iter_set_snapshot(&dst_iter, dst_snapshot);
 308
 309                 dst_done = dst_iter.pos.offset - dst_start.offset;
 310                 src_want = POS(src_start.inode, src_start.offset + dst_done);
 311                 bch2_btree_iter_set_pos(&src_iter, src_want);
 312
 313                 src_k = get_next_src(&src_iter, src_end);
 314                 ret = bkey_err(src_k);
 315                 if (ret)
 316                         continue;
 317
 318                 if (bkey_lt(src_want, src_iter.pos)) {
 319                         ret = bch2_fpunch_at(trans, &dst_iter, dst_inum,
 320                                         min(dst_end.offset,
 321                                             dst_iter.pos.offset +
 322                                             src_iter.pos.offset - src_want.offset),
 323                                         i_sectors_delta);
 324                         continue;
 325                 }
 326
 327                 if (src_k.k->type != KEY_TYPE_reflink_p) {
 328                         bch2_btree_iter_set_pos_to_extent_start(&src_iter);
 329
 330                         bch2_bkey_buf_reassemble(&new_src, c, src_k);
 331                         src_k = bkey_i_to_s_c(new_src.k);
 332
 333                         ret = bch2_make_extent_indirect(trans, &src_iter,
 334                                                 new_src.k);
 335                         if (ret)
 336                                 continue;
 337
 338                         BUG_ON(src_k.k->type != KEY_TYPE_reflink_p);
 339                 }
 340
 341                 if (src_k.k->type == KEY_TYPE_reflink_p) {
 342                         struct bkey_s_c_reflink_p src_p =
 343                                 bkey_s_c_to_reflink_p(src_k);
 344                         struct bkey_i_reflink_p *dst_p =
 345                                 bkey_reflink_p_init(new_dst.k);
 346
 347                         u64 offset = le64_to_cpu(src_p.v->idx) +
 348                                 (src_want.offset -
 349                                  bkey_start_offset(src_k.k));
 350
 351                         dst_p->v.idx = cpu_to_le64(offset);
 352                 } else {
 353                         BUG();
 354                 }
 355
 356                 new_dst.k->k.p = dst_iter.pos;
 357                 bch2_key_resize(&new_dst.k->k,
 358                                 min(src_k.k->p.offset - src_want.offset,
 359                                     dst_end.offset - dst_iter.pos.offset));
 360
 361                 ret =   bch2_bkey_set_needs_rebalance(c, new_dst.k,
 362                                         opts.background_target,
 363                                         opts.background_compression) ?:
 364                         bch2_extent_update(trans, dst_inum, &dst_iter,
 365                                         new_dst.k, &disk_res,
 366                                         new_i_size, i_sectors_delta,
 367                                         true);
 368                 bch2_disk_reservation_put(c, &disk_res);
 369         }
 370         bch2_trans_iter_exit(trans, &dst_iter);
 371         bch2_trans_iter_exit(trans, &src_iter);
 372
 373         BUG_ON(!ret && !bkey_eq(dst_iter.pos, dst_end));
 374         BUG_ON(bkey_gt(dst_iter.pos, dst_end));
 375
 376         dst_done = dst_iter.pos.offset - dst_start.offset;
 377         new_i_size = min(dst_iter.pos.offset << 9, new_i_size);
 378
 379         do {
 380                 struct bch_inode_unpacked inode_u;
 381                 struct btree_iter inode_iter = { NULL };
 382
 383                 bch2_trans_begin(trans);
 384
 385                 ret2 = bch2_inode_peek(trans, &inode_iter, &inode_u,
 386                                        dst_inum, BTREE_ITER_INTENT);
 387
 388                 if (!ret2 &&
 389                     inode_u.bi_size < new_i_size) {
 390                         inode_u.bi_size = new_i_size;
 391                         ret2  = bch2_inode_write(trans, &inode_iter, &inode_u) ?:
 392                                 bch2_trans_commit(trans, NULL, NULL,
 393                                                   BCH_TRANS_COMMIT_no_enospc);
 394                 }
 395
 396                 bch2_trans_iter_exit(trans, &inode_iter);
 397         } while (bch2_err_matches(ret2, BCH_ERR_transaction_restart));
 398 err:
 399         bch2_trans_put(trans);
 400         bch2_bkey_buf_exit(&new_src, c);
 401         bch2_bkey_buf_exit(&new_dst, c);
 402
 403         bch2_write_ref_put(c, BCH_WRITE_REF_reflink);
 404
 405         return dst_done ?: ret ?: ret2;
 406 }