git.sesse.net Git - bcachefs-tools-debian/blob - libbcachefs/fs-common.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include "bcachefs.h"
   4 #include "acl.h"
   5 #include "btree_update.h"
   6 #include "dirent.h"
   7 #include "fs-common.h"
   8 #include "inode.h"
   9 #include "subvolume.h"
  10 #include "xattr.h"
  11
  12 #include <linux/posix_acl.h>
  13
  14 static inline int is_subdir_for_nlink(struct bch_inode_unpacked *inode)
  15 {
  16         return S_ISDIR(inode->bi_mode) && !inode->bi_subvol;
  17 }
  18
  19 int bch2_create_trans(struct btree_trans *trans,
  20                       subvol_inum dir,
  21                       struct bch_inode_unpacked *dir_u,
  22                       struct bch_inode_unpacked *new_inode,
  23                       const struct qstr *name,
  24                       uid_t uid, gid_t gid, umode_t mode, dev_t rdev,
  25                       struct posix_acl *default_acl,
  26                       struct posix_acl *acl,
  27                       subvol_inum snapshot_src,
  28                       unsigned flags)
  29 {
  30         struct bch_fs *c = trans->c;
  31         struct btree_iter dir_iter = { NULL };
  32         struct btree_iter inode_iter = { NULL };
  33         subvol_inum new_inum = dir;
  34         u64 now = bch2_current_time(c);
  35         u64 cpu = raw_smp_processor_id();
  36         u64 dir_target;
  37         u32 snapshot;
  38         unsigned dir_type = mode_to_type(mode);
  39         int ret;
  40
  41         ret = bch2_subvolume_get_snapshot(trans, dir.subvol, &snapshot);
  42         if (ret)
  43                 goto err;
  44
  45         ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir, BTREE_ITER_INTENT);
  46         if (ret)
  47                 goto err;
  48
  49         if (!(flags & BCH_CREATE_SNAPSHOT)) {
  50                 /* Normal create path - allocate a new inode: */
  51                 bch2_inode_init_late(new_inode, now, uid, gid, mode, rdev, dir_u);
  52
  53                 if (flags & BCH_CREATE_TMPFILE)
  54                         new_inode->bi_flags |= BCH_INODE_UNLINKED;
  55
  56                 ret = bch2_inode_create(trans, &inode_iter, new_inode, snapshot, cpu);
  57                 if (ret)
  58                         goto err;
  59
  60                 snapshot_src = (subvol_inum) { 0 };
  61         } else {
  62                 /*
  63                  * Creating a snapshot - we're not allocating a new inode, but
  64                  * we do have to lookup the root inode of the subvolume we're
  65                  * snapshotting and update it (in the new snapshot):
  66                  */
  67
  68                 if (!snapshot_src.inum) {
  69                         /* Inode wasn't specified, just snapshot: */
  70                         struct bch_subvolume s;
  71
  72                         ret = bch2_subvolume_get(trans, snapshot_src.subvol, true,
  73                                                  BTREE_ITER_CACHED, &s);
  74                         if (ret)
  75                                 goto err;
  76
  77                         snapshot_src.inum = le64_to_cpu(s.inode);
  78                 }
  79
  80                 ret = bch2_inode_peek(trans, &inode_iter, new_inode, snapshot_src,
  81                                       BTREE_ITER_INTENT);
  82                 if (ret)
  83                         goto err;
  84
  85                 if (new_inode->bi_subvol != snapshot_src.subvol) {
  86                         /* Not a subvolume root: */
  87                         ret = -EINVAL;
  88                         goto err;
  89                 }
  90
  91                 /*
  92                  * If we're not root, we have to own the subvolume being
  93                  * snapshotted:
  94                  */
  95                 if (uid && new_inode->bi_uid != uid) {
  96                         ret = -EPERM;
  97                         goto err;
  98                 }
  99
 100                 flags |= BCH_CREATE_SUBVOL;
 101         }
 102
 103         new_inum.inum   = new_inode->bi_inum;
 104         dir_target      = new_inode->bi_inum;
 105
 106         if (flags & BCH_CREATE_SUBVOL) {
 107                 u32 new_subvol, dir_snapshot;
 108
 109                 ret = bch2_subvolume_create(trans, new_inode->bi_inum,
 110                                             snapshot_src.subvol,
 111                                             &new_subvol, &snapshot,
 112                                             (flags & BCH_CREATE_SNAPSHOT_RO) != 0);
 113                 if (ret)
 114                         goto err;
 115
 116                 new_inode->bi_parent_subvol     = dir.subvol;
 117                 new_inode->bi_subvol            = new_subvol;
 118                 new_inum.subvol                 = new_subvol;
 119                 dir_target                      = new_subvol;
 120                 dir_type                        = DT_SUBVOL;
 121
 122                 ret = bch2_subvolume_get_snapshot(trans, dir.subvol, &dir_snapshot);
 123                 if (ret)
 124                         goto err;
 125
 126                 bch2_btree_iter_set_snapshot(&dir_iter, dir_snapshot);
 127                 ret = bch2_btree_iter_traverse(&dir_iter);
 128                 if (ret)
 129                         goto err;
 130         }
 131
 132         if (!(flags & BCH_CREATE_SNAPSHOT)) {
 133                 if (default_acl) {
 134                         ret = bch2_set_acl_trans(trans, new_inum, new_inode,
 135                                                  default_acl, ACL_TYPE_DEFAULT);
 136                         if (ret)
 137                                 goto err;
 138                 }
 139
 140                 if (acl) {
 141                         ret = bch2_set_acl_trans(trans, new_inum, new_inode,
 142                                                  acl, ACL_TYPE_ACCESS);
 143                         if (ret)
 144                                 goto err;
 145                 }
 146         }
 147
 148         if (!(flags & BCH_CREATE_TMPFILE)) {
 149                 struct bch_hash_info dir_hash = bch2_hash_info_init(c, dir_u);
 150                 u64 dir_offset;
 151
 152                 if (is_subdir_for_nlink(new_inode))
 153                         dir_u->bi_nlink++;
 154                 dir_u->bi_mtime = dir_u->bi_ctime = now;
 155
 156                 ret = bch2_inode_write(trans, &dir_iter, dir_u);
 157                 if (ret)
 158                         goto err;
 159
 160                 ret = bch2_dirent_create(trans, dir, &dir_hash,
 161                                          dir_type,
 162                                          name,
 163                                          dir_target,
 164                                          &dir_offset,
 165                                          BCH_HASH_SET_MUST_CREATE);
 166                 if (ret)
 167                         goto err;
 168
 169                 if (c->sb.version >= bcachefs_metadata_version_inode_backpointers) {
 170                         new_inode->bi_dir               = dir_u->bi_inum;
 171                         new_inode->bi_dir_offset        = dir_offset;
 172                 }
 173         }
 174
 175         inode_iter.flags &= ~BTREE_ITER_ALL_SNAPSHOTS;
 176         bch2_btree_iter_set_snapshot(&inode_iter, snapshot);
 177
 178         ret   = bch2_btree_iter_traverse(&inode_iter) ?:
 179                 bch2_inode_write(trans, &inode_iter, new_inode);
 180 err:
 181         bch2_trans_iter_exit(trans, &inode_iter);
 182         bch2_trans_iter_exit(trans, &dir_iter);
 183         return ret;
 184 }
 185
 186 int bch2_link_trans(struct btree_trans *trans,
 187                     subvol_inum dir,  struct bch_inode_unpacked *dir_u,
 188                     subvol_inum inum, struct bch_inode_unpacked *inode_u,
 189                     const struct qstr *name)
 190 {
 191         struct bch_fs *c = trans->c;
 192         struct btree_iter dir_iter = { NULL };
 193         struct btree_iter inode_iter = { NULL };
 194         struct bch_hash_info dir_hash;
 195         u64 now = bch2_current_time(c);
 196         u64 dir_offset = 0;
 197         int ret;
 198
 199         if (dir.subvol != inum.subvol)
 200                 return -EXDEV;
 201
 202         ret = bch2_inode_peek(trans, &inode_iter, inode_u, inum, BTREE_ITER_INTENT);
 203         if (ret)
 204                 goto err;
 205
 206         inode_u->bi_ctime = now;
 207         ret = bch2_inode_nlink_inc(inode_u);
 208         if (ret)
 209                 return ret;
 210
 211         ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir, BTREE_ITER_INTENT);
 212         if (ret)
 213                 goto err;
 214
 215         if (bch2_reinherit_attrs(inode_u, dir_u)) {
 216                 ret = -EXDEV;
 217                 goto err;
 218         }
 219
 220         dir_u->bi_mtime = dir_u->bi_ctime = now;
 221
 222         dir_hash = bch2_hash_info_init(c, dir_u);
 223
 224         ret = bch2_dirent_create(trans, dir, &dir_hash,
 225                                  mode_to_type(inode_u->bi_mode),
 226                                  name, inum.inum, &dir_offset,
 227                                  BCH_HASH_SET_MUST_CREATE);
 228         if (ret)
 229                 goto err;
 230
 231         if (c->sb.version >= bcachefs_metadata_version_inode_backpointers) {
 232                 inode_u->bi_dir         = dir.inum;
 233                 inode_u->bi_dir_offset  = dir_offset;
 234         }
 235
 236         ret =   bch2_inode_write(trans, &dir_iter, dir_u) ?:
 237                 bch2_inode_write(trans, &inode_iter, inode_u);
 238 err:
 239         bch2_trans_iter_exit(trans, &dir_iter);
 240         bch2_trans_iter_exit(trans, &inode_iter);
 241         return ret;
 242 }
 243
 244 int bch2_unlink_trans(struct btree_trans *trans,
 245                       subvol_inum dir,
 246                       struct bch_inode_unpacked *dir_u,
 247                       struct bch_inode_unpacked *inode_u,
 248                       const struct qstr *name,
 249                       bool deleting_snapshot)
 250 {
 251         struct bch_fs *c = trans->c;
 252         struct btree_iter dir_iter = { NULL };
 253         struct btree_iter dirent_iter = { NULL };
 254         struct btree_iter inode_iter = { NULL };
 255         struct bch_hash_info dir_hash;
 256         subvol_inum inum;
 257         u64 now = bch2_current_time(c);
 258         struct bkey_s_c k;
 259         int ret;
 260
 261         ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir, BTREE_ITER_INTENT);
 262         if (ret)
 263                 goto err;
 264
 265         dir_hash = bch2_hash_info_init(c, dir_u);
 266
 267         ret = __bch2_dirent_lookup_trans(trans, &dirent_iter, dir, &dir_hash,
 268                                          name, &inum, BTREE_ITER_INTENT);
 269         if (ret)
 270                 goto err;
 271
 272         ret = bch2_inode_peek(trans, &inode_iter, inode_u, inum,
 273                               BTREE_ITER_INTENT);
 274         if (ret)
 275                 goto err;
 276
 277         if (!deleting_snapshot && S_ISDIR(inode_u->bi_mode)) {
 278                 ret = bch2_empty_dir_trans(trans, inum);
 279                 if (ret)
 280                         goto err;
 281         }
 282
 283         if (deleting_snapshot && !inode_u->bi_subvol) {
 284                 ret = -BCH_ERR_ENOENT_not_subvol;
 285                 goto err;
 286         }
 287
 288         if (deleting_snapshot || inode_u->bi_subvol) {
 289                 ret = bch2_subvolume_unlink(trans, inode_u->bi_subvol);
 290                 if (ret)
 291                         goto err;
 292
 293                 k = bch2_btree_iter_peek_slot(&dirent_iter);
 294                 ret = bkey_err(k);
 295                 if (ret)
 296                         goto err;
 297
 298                 /*
 299                  * If we're deleting a subvolume, we need to really delete the
 300                  * dirent, not just emit a whiteout in the current snapshot:
 301                  */
 302                 bch2_btree_iter_set_snapshot(&dirent_iter, k.k->p.snapshot);
 303                 ret = bch2_btree_iter_traverse(&dirent_iter);
 304                 if (ret)
 305                         goto err;
 306         } else {
 307                 bch2_inode_nlink_dec(trans, inode_u);
 308         }
 309
 310         if (inode_u->bi_dir             == dirent_iter.pos.inode &&
 311             inode_u->bi_dir_offset      == dirent_iter.pos.offset) {
 312                 inode_u->bi_dir         = 0;
 313                 inode_u->bi_dir_offset  = 0;
 314         }
 315
 316         dir_u->bi_mtime = dir_u->bi_ctime = inode_u->bi_ctime = now;
 317         dir_u->bi_nlink -= is_subdir_for_nlink(inode_u);
 318
 319         ret =   bch2_hash_delete_at(trans, bch2_dirent_hash_desc,
 320                                     &dir_hash, &dirent_iter,
 321                                     BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE) ?:
 322                 bch2_inode_write(trans, &dir_iter, dir_u) ?:
 323                 bch2_inode_write(trans, &inode_iter, inode_u);
 324 err:
 325         bch2_trans_iter_exit(trans, &inode_iter);
 326         bch2_trans_iter_exit(trans, &dirent_iter);
 327         bch2_trans_iter_exit(trans, &dir_iter);
 328         return ret;
 329 }
 330
 331 bool bch2_reinherit_attrs(struct bch_inode_unpacked *dst_u,
 332                           struct bch_inode_unpacked *src_u)
 333 {
 334         u64 src, dst;
 335         unsigned id;
 336         bool ret = false;
 337
 338         for (id = 0; id < Inode_opt_nr; id++) {
 339                 /* Skip attributes that were explicitly set on this inode */
 340                 if (dst_u->bi_fields_set & (1 << id))
 341                         continue;
 342
 343                 src = bch2_inode_opt_get(src_u, id);
 344                 dst = bch2_inode_opt_get(dst_u, id);
 345
 346                 if (src == dst)
 347                         continue;
 348
 349                 bch2_inode_opt_set(dst_u, id, src);
 350                 ret = true;
 351         }
 352
 353         return ret;
 354 }
 355
 356 int bch2_rename_trans(struct btree_trans *trans,
 357                       subvol_inum src_dir, struct bch_inode_unpacked *src_dir_u,
 358                       subvol_inum dst_dir, struct bch_inode_unpacked *dst_dir_u,
 359                       struct bch_inode_unpacked *src_inode_u,
 360                       struct bch_inode_unpacked *dst_inode_u,
 361                       const struct qstr *src_name,
 362                       const struct qstr *dst_name,
 363                       enum bch_rename_mode mode)
 364 {
 365         struct bch_fs *c = trans->c;
 366         struct btree_iter src_dir_iter = { NULL };
 367         struct btree_iter dst_dir_iter = { NULL };
 368         struct btree_iter src_inode_iter = { NULL };
 369         struct btree_iter dst_inode_iter = { NULL };
 370         struct bch_hash_info src_hash, dst_hash;
 371         subvol_inum src_inum, dst_inum;
 372         u64 src_offset, dst_offset;
 373         u64 now = bch2_current_time(c);
 374         int ret;
 375
 376         ret = bch2_inode_peek(trans, &src_dir_iter, src_dir_u, src_dir,
 377                               BTREE_ITER_INTENT);
 378         if (ret)
 379                 goto err;
 380
 381         src_hash = bch2_hash_info_init(c, src_dir_u);
 382
 383         if (dst_dir.inum        != src_dir.inum ||
 384             dst_dir.subvol      != src_dir.subvol) {
 385                 ret = bch2_inode_peek(trans, &dst_dir_iter, dst_dir_u, dst_dir,
 386                                       BTREE_ITER_INTENT);
 387                 if (ret)
 388                         goto err;
 389
 390                 dst_hash = bch2_hash_info_init(c, dst_dir_u);
 391         } else {
 392                 dst_dir_u = src_dir_u;
 393                 dst_hash = src_hash;
 394         }
 395
 396         ret = bch2_dirent_rename(trans,
 397                                  src_dir, &src_hash,
 398                                  dst_dir, &dst_hash,
 399                                  src_name, &src_inum, &src_offset,
 400                                  dst_name, &dst_inum, &dst_offset,
 401                                  mode);
 402         if (ret)
 403                 goto err;
 404
 405         ret = bch2_inode_peek(trans, &src_inode_iter, src_inode_u, src_inum,
 406                               BTREE_ITER_INTENT);
 407         if (ret)
 408                 goto err;
 409
 410         if (dst_inum.inum) {
 411                 ret = bch2_inode_peek(trans, &dst_inode_iter, dst_inode_u, dst_inum,
 412                                       BTREE_ITER_INTENT);
 413                 if (ret)
 414                         goto err;
 415         }
 416
 417         if (c->sb.version >= bcachefs_metadata_version_inode_backpointers) {
 418                 src_inode_u->bi_dir             = dst_dir_u->bi_inum;
 419                 src_inode_u->bi_dir_offset      = dst_offset;
 420
 421                 if (mode == BCH_RENAME_EXCHANGE) {
 422                         dst_inode_u->bi_dir             = src_dir_u->bi_inum;
 423                         dst_inode_u->bi_dir_offset      = src_offset;
 424                 }
 425
 426                 if (mode == BCH_RENAME_OVERWRITE &&
 427                     dst_inode_u->bi_dir         == dst_dir_u->bi_inum &&
 428                     dst_inode_u->bi_dir_offset  == src_offset) {
 429                         dst_inode_u->bi_dir             = 0;
 430                         dst_inode_u->bi_dir_offset      = 0;
 431                 }
 432         }
 433
 434         if (mode == BCH_RENAME_OVERWRITE) {
 435                 if (S_ISDIR(src_inode_u->bi_mode) !=
 436                     S_ISDIR(dst_inode_u->bi_mode)) {
 437                         ret = -ENOTDIR;
 438                         goto err;
 439                 }
 440
 441                 if (S_ISDIR(dst_inode_u->bi_mode) &&
 442                     bch2_empty_dir_trans(trans, dst_inum)) {
 443                         ret = -ENOTEMPTY;
 444                         goto err;
 445                 }
 446         }
 447
 448         if (bch2_reinherit_attrs(src_inode_u, dst_dir_u) &&
 449             S_ISDIR(src_inode_u->bi_mode)) {
 450                 ret = -EXDEV;
 451                 goto err;
 452         }
 453
 454         if (mode == BCH_RENAME_EXCHANGE &&
 455             bch2_reinherit_attrs(dst_inode_u, src_dir_u) &&
 456             S_ISDIR(dst_inode_u->bi_mode)) {
 457                 ret = -EXDEV;
 458                 goto err;
 459         }
 460
 461         if (is_subdir_for_nlink(src_inode_u)) {
 462                 src_dir_u->bi_nlink--;
 463                 dst_dir_u->bi_nlink++;
 464         }
 465
 466         if (dst_inum.inum && is_subdir_for_nlink(dst_inode_u)) {
 467                 dst_dir_u->bi_nlink--;
 468                 src_dir_u->bi_nlink += mode == BCH_RENAME_EXCHANGE;
 469         }
 470
 471         if (mode == BCH_RENAME_OVERWRITE)
 472                 bch2_inode_nlink_dec(trans, dst_inode_u);
 473
 474         src_dir_u->bi_mtime             = now;
 475         src_dir_u->bi_ctime             = now;
 476
 477         if (src_dir.inum != dst_dir.inum) {
 478                 dst_dir_u->bi_mtime     = now;
 479                 dst_dir_u->bi_ctime     = now;
 480         }
 481
 482         src_inode_u->bi_ctime           = now;
 483
 484         if (dst_inum.inum)
 485                 dst_inode_u->bi_ctime   = now;
 486
 487         ret =   bch2_inode_write(trans, &src_dir_iter, src_dir_u) ?:
 488                 (src_dir.inum != dst_dir.inum
 489                  ? bch2_inode_write(trans, &dst_dir_iter, dst_dir_u)
 490                  : 0) ?:
 491                 bch2_inode_write(trans, &src_inode_iter, src_inode_u) ?:
 492                 (dst_inum.inum
 493                  ? bch2_inode_write(trans, &dst_inode_iter, dst_inode_u)
 494                  : 0);
 495 err:
 496         bch2_trans_iter_exit(trans, &dst_inode_iter);
 497         bch2_trans_iter_exit(trans, &src_inode_iter);
 498         bch2_trans_iter_exit(trans, &dst_dir_iter);
 499         bch2_trans_iter_exit(trans, &src_dir_iter);
 500         return ret;
 501 }