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                                             dir.subvol,
 111                                             snapshot_src.subvol,
 112                                             &new_subvol, &snapshot,
 113                                             (flags & BCH_CREATE_SNAPSHOT_RO) != 0);
 114                 if (ret)
 115                         goto err;
 116
 117                 new_inode->bi_parent_subvol     = dir.subvol;
 118                 new_inode->bi_subvol            = new_subvol;
 119                 new_inum.subvol                 = new_subvol;
 120                 dir_target                      = new_subvol;
 121                 dir_type                        = DT_SUBVOL;
 122
 123                 ret = bch2_subvolume_get_snapshot(trans, dir.subvol, &dir_snapshot);
 124                 if (ret)
 125                         goto err;
 126
 127                 bch2_btree_iter_set_snapshot(&dir_iter, dir_snapshot);
 128                 ret = bch2_btree_iter_traverse(&dir_iter);
 129                 if (ret)
 130                         goto err;
 131         }
 132
 133         if (!(flags & BCH_CREATE_SNAPSHOT)) {
 134                 if (default_acl) {
 135                         ret = bch2_set_acl_trans(trans, new_inum, new_inode,
 136                                                  default_acl, ACL_TYPE_DEFAULT);
 137                         if (ret)
 138                                 goto err;
 139                 }
 140
 141                 if (acl) {
 142                         ret = bch2_set_acl_trans(trans, new_inum, new_inode,
 143                                                  acl, ACL_TYPE_ACCESS);
 144                         if (ret)
 145                                 goto err;
 146                 }
 147         }
 148
 149         if (!(flags & BCH_CREATE_TMPFILE)) {
 150                 struct bch_hash_info dir_hash = bch2_hash_info_init(c, dir_u);
 151                 u64 dir_offset;
 152
 153                 if (is_subdir_for_nlink(new_inode))
 154                         dir_u->bi_nlink++;
 155                 dir_u->bi_mtime = dir_u->bi_ctime = now;
 156
 157                 ret = bch2_inode_write(trans, &dir_iter, dir_u);
 158                 if (ret)
 159                         goto err;
 160
 161                 ret = bch2_dirent_create(trans, dir, &dir_hash,
 162                                          dir_type,
 163                                          name,
 164                                          dir_target,
 165                                          &dir_offset,
 166                                          BCH_HASH_SET_MUST_CREATE);
 167                 if (ret)
 168                         goto err;
 169
 170                 new_inode->bi_dir               = dir_u->bi_inum;
 171                 new_inode->bi_dir_offset        = dir_offset;
 172         }
 173
 174         inode_iter.flags &= ~BTREE_ITER_ALL_SNAPSHOTS;
 175         bch2_btree_iter_set_snapshot(&inode_iter, snapshot);
 176
 177         ret   = bch2_btree_iter_traverse(&inode_iter) ?:
 178                 bch2_inode_write(trans, &inode_iter, new_inode);
 179 err:
 180         bch2_trans_iter_exit(trans, &inode_iter);
 181         bch2_trans_iter_exit(trans, &dir_iter);
 182         return ret;
 183 }
 184
 185 int bch2_link_trans(struct btree_trans *trans,
 186                     subvol_inum dir,  struct bch_inode_unpacked *dir_u,
 187                     subvol_inum inum, struct bch_inode_unpacked *inode_u,
 188                     const struct qstr *name)
 189 {
 190         struct bch_fs *c = trans->c;
 191         struct btree_iter dir_iter = { NULL };
 192         struct btree_iter inode_iter = { NULL };
 193         struct bch_hash_info dir_hash;
 194         u64 now = bch2_current_time(c);
 195         u64 dir_offset = 0;
 196         int ret;
 197
 198         if (dir.subvol != inum.subvol)
 199                 return -EXDEV;
 200
 201         ret = bch2_inode_peek(trans, &inode_iter, inode_u, inum, BTREE_ITER_INTENT);
 202         if (ret)
 203                 goto err;
 204
 205         inode_u->bi_ctime = now;
 206         ret = bch2_inode_nlink_inc(inode_u);
 207         if (ret)
 208                 return ret;
 209
 210         ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir, BTREE_ITER_INTENT);
 211         if (ret)
 212                 goto err;
 213
 214         if (bch2_reinherit_attrs(inode_u, dir_u)) {
 215                 ret = -EXDEV;
 216                 goto err;
 217         }
 218
 219         dir_u->bi_mtime = dir_u->bi_ctime = now;
 220
 221         dir_hash = bch2_hash_info_init(c, dir_u);
 222
 223         ret = bch2_dirent_create(trans, dir, &dir_hash,
 224                                  mode_to_type(inode_u->bi_mode),
 225                                  name, inum.inum, &dir_offset,
 226                                  BCH_HASH_SET_MUST_CREATE);
 227         if (ret)
 228                 goto err;
 229
 230         inode_u->bi_dir         = dir.inum;
 231         inode_u->bi_dir_offset  = dir_offset;
 232
 233         ret =   bch2_inode_write(trans, &dir_iter, dir_u) ?:
 234                 bch2_inode_write(trans, &inode_iter, inode_u);
 235 err:
 236         bch2_trans_iter_exit(trans, &dir_iter);
 237         bch2_trans_iter_exit(trans, &inode_iter);
 238         return ret;
 239 }
 240
 241 int bch2_unlink_trans(struct btree_trans *trans,
 242                       subvol_inum dir,
 243                       struct bch_inode_unpacked *dir_u,
 244                       struct bch_inode_unpacked *inode_u,
 245                       const struct qstr *name,
 246                       bool deleting_subvol)
 247 {
 248         struct bch_fs *c = trans->c;
 249         struct btree_iter dir_iter = { NULL };
 250         struct btree_iter dirent_iter = { NULL };
 251         struct btree_iter inode_iter = { NULL };
 252         struct bch_hash_info dir_hash;
 253         subvol_inum inum;
 254         u64 now = bch2_current_time(c);
 255         struct bkey_s_c k;
 256         int ret;
 257
 258         ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir, BTREE_ITER_INTENT);
 259         if (ret)
 260                 goto err;
 261
 262         dir_hash = bch2_hash_info_init(c, dir_u);
 263
 264         ret = bch2_dirent_lookup_trans(trans, &dirent_iter, dir, &dir_hash,
 265                                        name, &inum, BTREE_ITER_INTENT);
 266         if (ret)
 267                 goto err;
 268
 269         ret = bch2_inode_peek(trans, &inode_iter, inode_u, inum,
 270                               BTREE_ITER_INTENT);
 271         if (ret)
 272                 goto err;
 273
 274         if (!deleting_subvol && S_ISDIR(inode_u->bi_mode)) {
 275                 ret = bch2_empty_dir_trans(trans, inum);
 276                 if (ret)
 277                         goto err;
 278         }
 279
 280         if (deleting_subvol && !inode_u->bi_subvol) {
 281                 ret = -BCH_ERR_ENOENT_not_subvol;
 282                 goto err;
 283         }
 284
 285         if (inode_u->bi_subvol) {
 286                 /* Recursive subvolume destroy not allowed (yet?) */
 287                 ret = bch2_subvol_has_children(trans, inode_u->bi_subvol);
 288                 if (ret)
 289                         goto err;
 290         }
 291
 292         if (deleting_subvol || inode_u->bi_subvol) {
 293                 ret = bch2_subvolume_unlink(trans, inode_u->bi_subvol);
 294                 if (ret)
 295                         goto err;
 296
 297                 k = bch2_btree_iter_peek_slot(&dirent_iter);
 298                 ret = bkey_err(k);
 299                 if (ret)
 300                         goto err;
 301
 302                 /*
 303                  * If we're deleting a subvolume, we need to really delete the
 304                  * dirent, not just emit a whiteout in the current snapshot:
 305                  */
 306                 bch2_btree_iter_set_snapshot(&dirent_iter, k.k->p.snapshot);
 307                 ret = bch2_btree_iter_traverse(&dirent_iter);
 308                 if (ret)
 309                         goto err;
 310         } else {
 311                 bch2_inode_nlink_dec(trans, inode_u);
 312         }
 313
 314         if (inode_u->bi_dir             == dirent_iter.pos.inode &&
 315             inode_u->bi_dir_offset      == dirent_iter.pos.offset) {
 316                 inode_u->bi_dir         = 0;
 317                 inode_u->bi_dir_offset  = 0;
 318         }
 319
 320         dir_u->bi_mtime = dir_u->bi_ctime = inode_u->bi_ctime = now;
 321         dir_u->bi_nlink -= is_subdir_for_nlink(inode_u);
 322
 323         ret =   bch2_hash_delete_at(trans, bch2_dirent_hash_desc,
 324                                     &dir_hash, &dirent_iter,
 325                                     BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE) ?:
 326                 bch2_inode_write(trans, &dir_iter, dir_u) ?:
 327                 bch2_inode_write(trans, &inode_iter, inode_u);
 328 err:
 329         bch2_trans_iter_exit(trans, &inode_iter);
 330         bch2_trans_iter_exit(trans, &dirent_iter);
 331         bch2_trans_iter_exit(trans, &dir_iter);
 332         return ret;
 333 }
 334
 335 bool bch2_reinherit_attrs(struct bch_inode_unpacked *dst_u,
 336                           struct bch_inode_unpacked *src_u)
 337 {
 338         u64 src, dst;
 339         unsigned id;
 340         bool ret = false;
 341
 342         for (id = 0; id < Inode_opt_nr; id++) {
 343                 /* Skip attributes that were explicitly set on this inode */
 344                 if (dst_u->bi_fields_set & (1 << id))
 345                         continue;
 346
 347                 src = bch2_inode_opt_get(src_u, id);
 348                 dst = bch2_inode_opt_get(dst_u, id);
 349
 350                 if (src == dst)
 351                         continue;
 352
 353                 bch2_inode_opt_set(dst_u, id, src);
 354                 ret = true;
 355         }
 356
 357         return ret;
 358 }
 359
 360 int bch2_rename_trans(struct btree_trans *trans,
 361                       subvol_inum src_dir, struct bch_inode_unpacked *src_dir_u,
 362                       subvol_inum dst_dir, struct bch_inode_unpacked *dst_dir_u,
 363                       struct bch_inode_unpacked *src_inode_u,
 364                       struct bch_inode_unpacked *dst_inode_u,
 365                       const struct qstr *src_name,
 366                       const struct qstr *dst_name,
 367                       enum bch_rename_mode mode)
 368 {
 369         struct bch_fs *c = trans->c;
 370         struct btree_iter src_dir_iter = { NULL };
 371         struct btree_iter dst_dir_iter = { NULL };
 372         struct btree_iter src_inode_iter = { NULL };
 373         struct btree_iter dst_inode_iter = { NULL };
 374         struct bch_hash_info src_hash, dst_hash;
 375         subvol_inum src_inum, dst_inum;
 376         u64 src_offset, dst_offset;
 377         u64 now = bch2_current_time(c);
 378         int ret;
 379
 380         ret = bch2_inode_peek(trans, &src_dir_iter, src_dir_u, src_dir,
 381                               BTREE_ITER_INTENT);
 382         if (ret)
 383                 goto err;
 384
 385         src_hash = bch2_hash_info_init(c, src_dir_u);
 386
 387         if (dst_dir.inum        != src_dir.inum ||
 388             dst_dir.subvol      != src_dir.subvol) {
 389                 ret = bch2_inode_peek(trans, &dst_dir_iter, dst_dir_u, dst_dir,
 390                                       BTREE_ITER_INTENT);
 391                 if (ret)
 392                         goto err;
 393
 394                 dst_hash = bch2_hash_info_init(c, dst_dir_u);
 395         } else {
 396                 dst_dir_u = src_dir_u;
 397                 dst_hash = src_hash;
 398         }
 399
 400         ret = bch2_dirent_rename(trans,
 401                                  src_dir, &src_hash,
 402                                  dst_dir, &dst_hash,
 403                                  src_name, &src_inum, &src_offset,
 404                                  dst_name, &dst_inum, &dst_offset,
 405                                  mode);
 406         if (ret)
 407                 goto err;
 408
 409         ret = bch2_inode_peek(trans, &src_inode_iter, src_inode_u, src_inum,
 410                               BTREE_ITER_INTENT);
 411         if (ret)
 412                 goto err;
 413
 414         if (dst_inum.inum) {
 415                 ret = bch2_inode_peek(trans, &dst_inode_iter, dst_inode_u, dst_inum,
 416                                       BTREE_ITER_INTENT);
 417                 if (ret)
 418                         goto err;
 419         }
 420
 421         /* Can't move across subvolumes, unless it's a subvolume root: */
 422         if (src_dir.subvol != dst_dir.subvol &&
 423             (!src_inode_u->bi_subvol ||
 424              (dst_inum.inum && !dst_inode_u->bi_subvol))) {
 425                 ret = -EXDEV;
 426                 goto err;
 427         }
 428
 429         if (src_inode_u->bi_parent_subvol)
 430                 src_inode_u->bi_parent_subvol = dst_dir.subvol;
 431
 432         if ((mode == BCH_RENAME_EXCHANGE) &&
 433             dst_inode_u->bi_parent_subvol)
 434                 dst_inode_u->bi_parent_subvol = src_dir.subvol;
 435
 436         src_inode_u->bi_dir             = dst_dir_u->bi_inum;
 437         src_inode_u->bi_dir_offset      = dst_offset;
 438
 439         if (mode == BCH_RENAME_EXCHANGE) {
 440                 dst_inode_u->bi_dir             = src_dir_u->bi_inum;
 441                 dst_inode_u->bi_dir_offset      = src_offset;
 442         }
 443
 444         if (mode == BCH_RENAME_OVERWRITE &&
 445             dst_inode_u->bi_dir         == dst_dir_u->bi_inum &&
 446             dst_inode_u->bi_dir_offset  == src_offset) {
 447                 dst_inode_u->bi_dir             = 0;
 448                 dst_inode_u->bi_dir_offset      = 0;
 449         }
 450
 451         if (mode == BCH_RENAME_OVERWRITE) {
 452                 if (S_ISDIR(src_inode_u->bi_mode) !=
 453                     S_ISDIR(dst_inode_u->bi_mode)) {
 454                         ret = -ENOTDIR;
 455                         goto err;
 456                 }
 457
 458                 if (S_ISDIR(dst_inode_u->bi_mode) &&
 459                     bch2_empty_dir_trans(trans, dst_inum)) {
 460                         ret = -ENOTEMPTY;
 461                         goto err;
 462                 }
 463         }
 464
 465         if (bch2_reinherit_attrs(src_inode_u, dst_dir_u) &&
 466             S_ISDIR(src_inode_u->bi_mode)) {
 467                 ret = -EXDEV;
 468                 goto err;
 469         }
 470
 471         if (mode == BCH_RENAME_EXCHANGE &&
 472             bch2_reinherit_attrs(dst_inode_u, src_dir_u) &&
 473             S_ISDIR(dst_inode_u->bi_mode)) {
 474                 ret = -EXDEV;
 475                 goto err;
 476         }
 477
 478         if (is_subdir_for_nlink(src_inode_u)) {
 479                 src_dir_u->bi_nlink--;
 480                 dst_dir_u->bi_nlink++;
 481         }
 482
 483         if (dst_inum.inum && is_subdir_for_nlink(dst_inode_u)) {
 484                 dst_dir_u->bi_nlink--;
 485                 src_dir_u->bi_nlink += mode == BCH_RENAME_EXCHANGE;
 486         }
 487
 488         if (mode == BCH_RENAME_OVERWRITE)
 489                 bch2_inode_nlink_dec(trans, dst_inode_u);
 490
 491         src_dir_u->bi_mtime             = now;
 492         src_dir_u->bi_ctime             = now;
 493
 494         if (src_dir.inum != dst_dir.inum) {
 495                 dst_dir_u->bi_mtime     = now;
 496                 dst_dir_u->bi_ctime     = now;
 497         }
 498
 499         src_inode_u->bi_ctime           = now;
 500
 501         if (dst_inum.inum)
 502                 dst_inode_u->bi_ctime   = now;
 503
 504         ret =   bch2_inode_write(trans, &src_dir_iter, src_dir_u) ?:
 505                 (src_dir.inum != dst_dir.inum
 506                  ? bch2_inode_write(trans, &dst_dir_iter, dst_dir_u)
 507                  : 0) ?:
 508                 bch2_inode_write(trans, &src_inode_iter, src_inode_u) ?:
 509                 (dst_inum.inum
 510                  ? bch2_inode_write(trans, &dst_inode_iter, dst_inode_u)
 511                  : 0);
 512 err:
 513         bch2_trans_iter_exit(trans, &dst_inode_iter);
 514         bch2_trans_iter_exit(trans, &src_inode_iter);
 515         bch2_trans_iter_exit(trans, &dst_dir_iter);
 516         bch2_trans_iter_exit(trans, &src_dir_iter);
 517         return ret;
 518 }