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