git.sesse.net Git - bcachefs-tools-debian/blob - c_src/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                 new_inode->bi_dir               = dir_u->bi_inum;
 170                 new_inode->bi_dir_offset        = dir_offset;
 171         }
 172
 173         inode_iter.flags &= ~BTREE_ITER_ALL_SNAPSHOTS;
 174         bch2_btree_iter_set_snapshot(&inode_iter, snapshot);
 175
 176         ret   = bch2_btree_iter_traverse(&inode_iter) ?:
 177                 bch2_inode_write(trans, &inode_iter, new_inode);
 178 err:
 179         bch2_trans_iter_exit(trans, &inode_iter);
 180         bch2_trans_iter_exit(trans, &dir_iter);
 181         return ret;
 182 }
 183
 184 int bch2_link_trans(struct btree_trans *trans,
 185                     subvol_inum dir,  struct bch_inode_unpacked *dir_u,
 186                     subvol_inum inum, struct bch_inode_unpacked *inode_u,
 187                     const struct qstr *name)
 188 {
 189         struct bch_fs *c = trans->c;
 190         struct btree_iter dir_iter = { NULL };
 191         struct btree_iter inode_iter = { NULL };
 192         struct bch_hash_info dir_hash;
 193         u64 now = bch2_current_time(c);
 194         u64 dir_offset = 0;
 195         int ret;
 196
 197         if (dir.subvol != inum.subvol)
 198                 return -EXDEV;
 199
 200         ret = bch2_inode_peek(trans, &inode_iter, inode_u, inum, BTREE_ITER_INTENT);
 201         if (ret)
 202                 goto err;
 203
 204         inode_u->bi_ctime = now;
 205         ret = bch2_inode_nlink_inc(inode_u);
 206         if (ret)
 207                 return ret;
 208
 209         ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir, BTREE_ITER_INTENT);
 210         if (ret)
 211                 goto err;
 212
 213         if (bch2_reinherit_attrs(inode_u, dir_u)) {
 214                 ret = -EXDEV;
 215                 goto err;
 216         }
 217
 218         dir_u->bi_mtime = dir_u->bi_ctime = now;
 219
 220         dir_hash = bch2_hash_info_init(c, dir_u);
 221
 222         ret = bch2_dirent_create(trans, dir, &dir_hash,
 223                                  mode_to_type(inode_u->bi_mode),
 224                                  name, inum.inum, &dir_offset,
 225                                  BCH_HASH_SET_MUST_CREATE);
 226         if (ret)
 227                 goto err;
 228
 229         inode_u->bi_dir         = dir.inum;
 230         inode_u->bi_dir_offset  = dir_offset;
 231
 232         ret =   bch2_inode_write(trans, &dir_iter, dir_u) ?:
 233                 bch2_inode_write(trans, &inode_iter, inode_u);
 234 err:
 235         bch2_trans_iter_exit(trans, &dir_iter);
 236         bch2_trans_iter_exit(trans, &inode_iter);
 237         return ret;
 238 }
 239
 240 int bch2_unlink_trans(struct btree_trans *trans,
 241                       subvol_inum dir,
 242                       struct bch_inode_unpacked *dir_u,
 243                       struct bch_inode_unpacked *inode_u,
 244                       const struct qstr *name,
 245                       bool deleting_snapshot)
 246 {
 247         struct bch_fs *c = trans->c;
 248         struct btree_iter dir_iter = { NULL };
 249         struct btree_iter dirent_iter = { NULL };
 250         struct btree_iter inode_iter = { NULL };
 251         struct bch_hash_info dir_hash;
 252         subvol_inum inum;
 253         u64 now = bch2_current_time(c);
 254         struct bkey_s_c k;
 255         int ret;
 256
 257         ret = bch2_inode_peek(trans, &dir_iter, dir_u, dir, BTREE_ITER_INTENT);
 258         if (ret)
 259                 goto err;
 260
 261         dir_hash = bch2_hash_info_init(c, dir_u);
 262
 263         ret = __bch2_dirent_lookup_trans(trans, &dirent_iter, dir, &dir_hash,
 264                                          name, &inum, BTREE_ITER_INTENT);
 265         if (ret)
 266                 goto err;
 267
 268         ret = bch2_inode_peek(trans, &inode_iter, inode_u, inum,
 269                               BTREE_ITER_INTENT);
 270         if (ret)
 271                 goto err;
 272
 273         if (!deleting_snapshot && S_ISDIR(inode_u->bi_mode)) {
 274                 ret = bch2_empty_dir_trans(trans, inum);
 275                 if (ret)
 276                         goto err;
 277         }
 278
 279         if (deleting_snapshot && !inode_u->bi_subvol) {
 280                 ret = -BCH_ERR_ENOENT_not_subvol;
 281                 goto err;
 282         }
 283
 284         if (deleting_snapshot || inode_u->bi_subvol) {
 285                 ret = bch2_subvolume_unlink(trans, inode_u->bi_subvol);
 286                 if (ret)
 287                         goto err;
 288
 289                 k = bch2_btree_iter_peek_slot(&dirent_iter);
 290                 ret = bkey_err(k);
 291                 if (ret)
 292                         goto err;
 293
 294                 /*
 295                  * If we're deleting a subvolume, we need to really delete the
 296                  * dirent, not just emit a whiteout in the current snapshot:
 297                  */
 298                 bch2_btree_iter_set_snapshot(&dirent_iter, k.k->p.snapshot);
 299                 ret = bch2_btree_iter_traverse(&dirent_iter);
 300                 if (ret)
 301                         goto err;
 302         } else {
 303                 bch2_inode_nlink_dec(trans, inode_u);
 304         }
 305
 306         if (inode_u->bi_dir             == dirent_iter.pos.inode &&
 307             inode_u->bi_dir_offset      == dirent_iter.pos.offset) {
 308                 inode_u->bi_dir         = 0;
 309                 inode_u->bi_dir_offset  = 0;
 310         }
 311
 312         dir_u->bi_mtime = dir_u->bi_ctime = inode_u->bi_ctime = now;
 313         dir_u->bi_nlink -= is_subdir_for_nlink(inode_u);
 314
 315         ret =   bch2_hash_delete_at(trans, bch2_dirent_hash_desc,
 316                                     &dir_hash, &dirent_iter,
 317                                     BTREE_UPDATE_INTERNAL_SNAPSHOT_NODE) ?:
 318                 bch2_inode_write(trans, &dir_iter, dir_u) ?:
 319                 bch2_inode_write(trans, &inode_iter, inode_u);
 320 err:
 321         bch2_trans_iter_exit(trans, &inode_iter);
 322         bch2_trans_iter_exit(trans, &dirent_iter);
 323         bch2_trans_iter_exit(trans, &dir_iter);
 324         return ret;
 325 }
 326
 327 bool bch2_reinherit_attrs(struct bch_inode_unpacked *dst_u,
 328                           struct bch_inode_unpacked *src_u)
 329 {
 330         u64 src, dst;
 331         unsigned id;
 332         bool ret = false;
 333
 334         for (id = 0; id < Inode_opt_nr; id++) {
 335                 /* Skip attributes that were explicitly set on this inode */
 336                 if (dst_u->bi_fields_set & (1 << id))
 337                         continue;
 338
 339                 src = bch2_inode_opt_get(src_u, id);
 340                 dst = bch2_inode_opt_get(dst_u, id);
 341
 342                 if (src == dst)
 343                         continue;
 344
 345                 bch2_inode_opt_set(dst_u, id, src);
 346                 ret = true;
 347         }
 348
 349         return ret;
 350 }
 351
 352 int bch2_rename_trans(struct btree_trans *trans,
 353                       subvol_inum src_dir, struct bch_inode_unpacked *src_dir_u,
 354                       subvol_inum dst_dir, struct bch_inode_unpacked *dst_dir_u,
 355                       struct bch_inode_unpacked *src_inode_u,
 356                       struct bch_inode_unpacked *dst_inode_u,
 357                       const struct qstr *src_name,
 358                       const struct qstr *dst_name,
 359                       enum bch_rename_mode mode)
 360 {
 361         struct bch_fs *c = trans->c;
 362         struct btree_iter src_dir_iter = { NULL };
 363         struct btree_iter dst_dir_iter = { NULL };
 364         struct btree_iter src_inode_iter = { NULL };
 365         struct btree_iter dst_inode_iter = { NULL };
 366         struct bch_hash_info src_hash, dst_hash;
 367         subvol_inum src_inum, dst_inum;
 368         u64 src_offset, dst_offset;
 369         u64 now = bch2_current_time(c);
 370         int ret;
 371
 372         ret = bch2_inode_peek(trans, &src_dir_iter, src_dir_u, src_dir,
 373                               BTREE_ITER_INTENT);
 374         if (ret)
 375                 goto err;
 376
 377         src_hash = bch2_hash_info_init(c, src_dir_u);
 378
 379         if (dst_dir.inum        != src_dir.inum ||
 380             dst_dir.subvol      != src_dir.subvol) {
 381                 ret = bch2_inode_peek(trans, &dst_dir_iter, dst_dir_u, dst_dir,
 382                                       BTREE_ITER_INTENT);
 383                 if (ret)
 384                         goto err;
 385
 386                 dst_hash = bch2_hash_info_init(c, dst_dir_u);
 387         } else {
 388                 dst_dir_u = src_dir_u;
 389                 dst_hash = src_hash;
 390         }
 391
 392         ret = bch2_dirent_rename(trans,
 393                                  src_dir, &src_hash,
 394                                  dst_dir, &dst_hash,
 395                                  src_name, &src_inum, &src_offset,
 396                                  dst_name, &dst_inum, &dst_offset,
 397                                  mode);
 398         if (ret)
 399                 goto err;
 400
 401         ret = bch2_inode_peek(trans, &src_inode_iter, src_inode_u, src_inum,
 402                               BTREE_ITER_INTENT);
 403         if (ret)
 404                 goto err;
 405
 406         if (dst_inum.inum) {
 407                 ret = bch2_inode_peek(trans, &dst_inode_iter, dst_inode_u, dst_inum,
 408                                       BTREE_ITER_INTENT);
 409                 if (ret)
 410                         goto err;
 411         }
 412
 413         src_inode_u->bi_dir             = dst_dir_u->bi_inum;
 414         src_inode_u->bi_dir_offset      = dst_offset;
 415
 416         if (mode == BCH_RENAME_EXCHANGE) {
 417                 dst_inode_u->bi_dir             = src_dir_u->bi_inum;
 418                 dst_inode_u->bi_dir_offset      = src_offset;
 419         }
 420
 421         if (mode == BCH_RENAME_OVERWRITE &&
 422             dst_inode_u->bi_dir         == dst_dir_u->bi_inum &&
 423             dst_inode_u->bi_dir_offset  == src_offset) {
 424                 dst_inode_u->bi_dir             = 0;
 425                 dst_inode_u->bi_dir_offset      = 0;
 426         }
 427
 428         if (mode == BCH_RENAME_OVERWRITE) {
 429                 if (S_ISDIR(src_inode_u->bi_mode) !=
 430                     S_ISDIR(dst_inode_u->bi_mode)) {
 431                         ret = -ENOTDIR;
 432                         goto err;
 433                 }
 434
 435                 if (S_ISDIR(dst_inode_u->bi_mode) &&
 436                     bch2_empty_dir_trans(trans, dst_inum)) {
 437                         ret = -ENOTEMPTY;
 438                         goto err;
 439                 }
 440         }
 441
 442         if (bch2_reinherit_attrs(src_inode_u, dst_dir_u) &&
 443             S_ISDIR(src_inode_u->bi_mode)) {
 444                 ret = -EXDEV;
 445                 goto err;
 446         }
 447
 448         if (mode == BCH_RENAME_EXCHANGE &&
 449             bch2_reinherit_attrs(dst_inode_u, src_dir_u) &&
 450             S_ISDIR(dst_inode_u->bi_mode)) {
 451                 ret = -EXDEV;
 452                 goto err;
 453         }
 454
 455         if (is_subdir_for_nlink(src_inode_u)) {
 456                 src_dir_u->bi_nlink--;
 457                 dst_dir_u->bi_nlink++;
 458         }
 459
 460         if (dst_inum.inum && is_subdir_for_nlink(dst_inode_u)) {
 461                 dst_dir_u->bi_nlink--;
 462                 src_dir_u->bi_nlink += mode == BCH_RENAME_EXCHANGE;
 463         }
 464
 465         if (mode == BCH_RENAME_OVERWRITE)
 466                 bch2_inode_nlink_dec(trans, dst_inode_u);
 467
 468         src_dir_u->bi_mtime             = now;
 469         src_dir_u->bi_ctime             = now;
 470
 471         if (src_dir.inum != dst_dir.inum) {
 472                 dst_dir_u->bi_mtime     = now;
 473                 dst_dir_u->bi_ctime     = now;
 474         }
 475
 476         src_inode_u->bi_ctime           = now;
 477
 478         if (dst_inum.inum)
 479                 dst_inode_u->bi_ctime   = now;
 480
 481         ret =   bch2_inode_write(trans, &src_dir_iter, src_dir_u) ?:
 482                 (src_dir.inum != dst_dir.inum
 483                  ? bch2_inode_write(trans, &dst_dir_iter, dst_dir_u)
 484                  : 0) ?:
 485                 bch2_inode_write(trans, &src_inode_iter, src_inode_u) ?:
 486                 (dst_inum.inum
 487                  ? bch2_inode_write(trans, &dst_inode_iter, dst_inode_u)
 488                  : 0);
 489 err:
 490         bch2_trans_iter_exit(trans, &dst_inode_iter);
 491         bch2_trans_iter_exit(trans, &src_inode_iter);
 492         bch2_trans_iter_exit(trans, &dst_dir_iter);
 493         bch2_trans_iter_exit(trans, &src_dir_iter);
 494         return ret;
 495 }