fs/affs/inode.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/affs/inode.c
   4  *
   5  *  (c) 1996  Hans-Joachim Widmaier - Rewritten
   6  *
   7  *  (C) 1993  Ray Burr - Modified for Amiga FFS filesystem.
   8  *
   9  *  (C) 1992  Eric Youngdale Modified for ISO9660 filesystem.
  10  *
  11  *  (C) 1991  Linus Torvalds - minix filesystem
  12  */
  13 #include <linux/sched.h>
  14 #include <linux/cred.h>
  15 #include <linux/gfp.h>
  16 #include "affs.h"
  17
  18 struct inode *affs_iget(struct super_block *sb, unsigned long ino)
  19 {
  20         struct affs_sb_info     *sbi = AFFS_SB(sb);
  21         struct buffer_head      *bh;
  22         struct affs_tail        *tail;
  23         struct inode            *inode;
  24         u32                      block;
  25         u32                      size;
  26         u32                      prot;
  27         u16                      id;
  28
  29         inode = iget_locked(sb, ino);
  30         if (!inode)
  31                 return ERR_PTR(-ENOMEM);
  32         if (!(inode->i_state & I_NEW))
  33                 return inode;
  34
  35         pr_debug("affs_iget(%lu)\n", inode->i_ino);
  36
  37         block = inode->i_ino;
  38         bh = affs_bread(sb, block);
  39         if (!bh) {
  40                 affs_warning(sb, "read_inode", "Cannot read block %d", block);
  41                 goto bad_inode;
  42         }
  43         if (affs_checksum_block(sb, bh) || be32_to_cpu(AFFS_HEAD(bh)->ptype) != T_SHORT) {
  44                 affs_warning(sb,"read_inode",
  45                            "Checksum or type (ptype=%d) error on inode %d",
  46                            AFFS_HEAD(bh)->ptype, block);
  47                 goto bad_inode;
  48         }
  49
  50         tail = AFFS_TAIL(sb, bh);
  51         prot = be32_to_cpu(tail->protect);
  52
  53         inode->i_size = 0;
  54         set_nlink(inode, 1);
  55         inode->i_mode = 0;
  56         AFFS_I(inode)->i_extcnt = 1;
  57         AFFS_I(inode)->i_ext_last = ~1;
  58         AFFS_I(inode)->i_protect = prot;
  59         atomic_set(&AFFS_I(inode)->i_opencnt, 0);
  60         AFFS_I(inode)->i_blkcnt = 0;
  61         AFFS_I(inode)->i_lc = NULL;
  62         AFFS_I(inode)->i_lc_size = 0;
  63         AFFS_I(inode)->i_lc_shift = 0;
  64         AFFS_I(inode)->i_lc_mask = 0;
  65         AFFS_I(inode)->i_ac = NULL;
  66         AFFS_I(inode)->i_ext_bh = NULL;
  67         AFFS_I(inode)->mmu_private = 0;
  68         AFFS_I(inode)->i_lastalloc = 0;
  69         AFFS_I(inode)->i_pa_cnt = 0;
  70
  71         if (affs_test_opt(sbi->s_flags, SF_SETMODE))
  72                 inode->i_mode = sbi->s_mode;
  73         else
  74                 inode->i_mode = affs_prot_to_mode(prot);
  75
  76         id = be16_to_cpu(tail->uid);
  77         if (id == 0 || affs_test_opt(sbi->s_flags, SF_SETUID))
  78                 inode->i_uid = sbi->s_uid;
  79         else if (id == 0xFFFF && affs_test_opt(sbi->s_flags, SF_MUFS))
  80                 i_uid_write(inode, 0);
  81         else
  82                 i_uid_write(inode, id);
  83
  84         id = be16_to_cpu(tail->gid);
  85         if (id == 0 || affs_test_opt(sbi->s_flags, SF_SETGID))
  86                 inode->i_gid = sbi->s_gid;
  87         else if (id == 0xFFFF && affs_test_opt(sbi->s_flags, SF_MUFS))
  88                 i_gid_write(inode, 0);
  89         else
  90                 i_gid_write(inode, id);
  91
  92         switch (be32_to_cpu(tail->stype)) {
  93         case ST_ROOT:
  94                 inode->i_uid = sbi->s_uid;
  95                 inode->i_gid = sbi->s_gid;
  96                 fallthrough;
  97         case ST_USERDIR:
  98                 if (be32_to_cpu(tail->stype) == ST_USERDIR ||
  99                     affs_test_opt(sbi->s_flags, SF_SETMODE)) {
 100                         if (inode->i_mode & S_IRUSR)
 101                                 inode->i_mode |= S_IXUSR;
 102                         if (inode->i_mode & S_IRGRP)
 103                                 inode->i_mode |= S_IXGRP;
 104                         if (inode->i_mode & S_IROTH)
 105                                 inode->i_mode |= S_IXOTH;
 106                         inode->i_mode |= S_IFDIR;
 107                 } else
 108                         inode->i_mode = S_IRUGO | S_IXUGO | S_IWUSR | S_IFDIR;
 109                 /* Maybe it should be controlled by mount parameter? */
 110                 //inode->i_mode |= S_ISVTX;
 111                 inode->i_op = &affs_dir_inode_operations;
 112                 inode->i_fop = &affs_dir_operations;
 113                 break;
 114         case ST_LINKDIR:
 115 #if 0
 116                 affs_warning(sb, "read_inode", "inode is LINKDIR");
 117                 goto bad_inode;
 118 #else
 119                 inode->i_mode |= S_IFDIR;
 120                 /* ... and leave ->i_op and ->i_fop pointing to empty */
 121                 break;
 122 #endif
 123         case ST_LINKFILE:
 124                 affs_warning(sb, "read_inode", "inode is LINKFILE");
 125                 goto bad_inode;
 126         case ST_FILE:
 127                 size = be32_to_cpu(tail->size);
 128                 inode->i_mode |= S_IFREG;
 129                 AFFS_I(inode)->mmu_private = inode->i_size = size;
 130                 if (inode->i_size) {
 131                         AFFS_I(inode)->i_blkcnt = (size - 1) /
 132                                                sbi->s_data_blksize + 1;
 133                         AFFS_I(inode)->i_extcnt = (AFFS_I(inode)->i_blkcnt - 1) /
 134                                                sbi->s_hashsize + 1;
 135                 }
 136                 if (tail->link_chain)
 137                         set_nlink(inode, 2);
 138                 inode->i_mapping->a_ops = affs_test_opt(sbi->s_flags, SF_OFS) ?
 139                                           &affs_aops_ofs : &affs_aops;
 140                 inode->i_op = &affs_file_inode_operations;
 141                 inode->i_fop = &affs_file_operations;
 142                 break;
 143         case ST_SOFTLINK:
 144                 inode->i_size = strlen((char *)AFFS_HEAD(bh)->table);
 145                 inode->i_mode |= S_IFLNK;
 146                 inode_nohighmem(inode);
 147                 inode->i_op = &affs_symlink_inode_operations;
 148                 inode->i_data.a_ops = &affs_symlink_aops;
 149                 break;
 150         }
 151
 152         inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec
 153                        = (be32_to_cpu(tail->change.days) * 86400LL +
 154                          be32_to_cpu(tail->change.mins) * 60 +
 155                          be32_to_cpu(tail->change.ticks) / 50 +
 156                          AFFS_EPOCH_DELTA) +
 157                          sys_tz.tz_minuteswest * 60;
 158         inode->i_mtime.tv_nsec = inode->i_ctime.tv_nsec = inode->i_atime.tv_nsec = 0;
 159         affs_brelse(bh);
 160         unlock_new_inode(inode);
 161         return inode;
 162
 163 bad_inode:
 164         affs_brelse(bh);
 165         iget_failed(inode);
 166         return ERR_PTR(-EIO);
 167 }
 168
 169 int
 170 affs_write_inode(struct inode *inode, struct writeback_control *wbc)
 171 {
 172         struct super_block      *sb = inode->i_sb;
 173         struct buffer_head      *bh;
 174         struct affs_tail        *tail;
 175         uid_t                    uid;
 176         gid_t                    gid;
 177
 178         pr_debug("write_inode(%lu)\n", inode->i_ino);
 179
 180         if (!inode->i_nlink)
 181                 // possibly free block
 182                 return 0;
 183         bh = affs_bread(sb, inode->i_ino);
 184         if (!bh) {
 185                 affs_error(sb,"write_inode","Cannot read block %lu",inode->i_ino);
 186                 return -EIO;
 187         }
 188         tail = AFFS_TAIL(sb, bh);
 189         if (tail->stype == cpu_to_be32(ST_ROOT)) {
 190                 affs_secs_to_datestamp(inode->i_mtime.tv_sec,
 191                                        &AFFS_ROOT_TAIL(sb, bh)->root_change);
 192         } else {
 193                 tail->protect = cpu_to_be32(AFFS_I(inode)->i_protect);
 194                 tail->size = cpu_to_be32(inode->i_size);
 195                 affs_secs_to_datestamp(inode->i_mtime.tv_sec, &tail->change);
 196                 if (!(inode->i_ino == AFFS_SB(sb)->s_root_block)) {
 197                         uid = i_uid_read(inode);
 198                         gid = i_gid_read(inode);
 199                         if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_MUFS)) {
 200                                 if (uid == 0 || uid == 0xFFFF)
 201                                         uid = uid ^ ~0;
 202                                 if (gid == 0 || gid == 0xFFFF)
 203                                         gid = gid ^ ~0;
 204                         }
 205                         if (!affs_test_opt(AFFS_SB(sb)->s_flags, SF_SETUID))
 206                                 tail->uid = cpu_to_be16(uid);
 207                         if (!affs_test_opt(AFFS_SB(sb)->s_flags, SF_SETGID))
 208                                 tail->gid = cpu_to_be16(gid);
 209                 }
 210         }
 211         affs_fix_checksum(sb, bh);
 212         mark_buffer_dirty_inode(bh, inode);
 213         affs_brelse(bh);
 214         affs_free_prealloc(inode);
 215         return 0;
 216 }
 217
 218 int
 219 affs_notify_change(struct user_namespace *mnt_userns, struct dentry *dentry,
 220                    struct iattr *attr)
 221 {
 222         struct inode *inode = d_inode(dentry);
 223         int error;
 224
 225         pr_debug("notify_change(%lu,0x%x)\n", inode->i_ino, attr->ia_valid);
 226
 227         error = setattr_prepare(&init_user_ns, dentry, attr);
 228         if (error)
 229                 goto out;
 230
 231         if (((attr->ia_valid & ATTR_UID) &&
 232               affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_SETUID)) ||
 233             ((attr->ia_valid & ATTR_GID) &&
 234               affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_SETGID)) ||
 235             ((attr->ia_valid & ATTR_MODE) &&
 236              (AFFS_SB(inode->i_sb)->s_flags &
 237               (AFFS_MOUNT_SF_SETMODE | AFFS_MOUNT_SF_IMMUTABLE)))) {
 238                 if (!affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_QUIET))
 239                         error = -EPERM;
 240                 goto out;
 241         }
 242
 243         if ((attr->ia_valid & ATTR_SIZE) &&
 244             attr->ia_size != i_size_read(inode)) {
 245                 error = inode_newsize_ok(inode, attr->ia_size);
 246                 if (error)
 247                         return error;
 248
 249                 truncate_setsize(inode, attr->ia_size);
 250                 affs_truncate(inode);
 251         }
 252
 253         setattr_copy(&init_user_ns, inode, attr);
 254         mark_inode_dirty(inode);
 255
 256         if (attr->ia_valid & ATTR_MODE)
 257                 affs_mode_to_prot(inode);
 258 out:
 259         return error;
 260 }
 261
 262 void
 263 affs_evict_inode(struct inode *inode)
 264 {
 265         unsigned long cache_page;
 266         pr_debug("evict_inode(ino=%lu, nlink=%u)\n",
 267                  inode->i_ino, inode->i_nlink);
 268         truncate_inode_pages_final(&inode->i_data);
 269
 270         if (!inode->i_nlink) {
 271                 inode->i_size = 0;
 272                 affs_truncate(inode);
 273         }
 274
 275         invalidate_inode_buffers(inode);
 276         clear_inode(inode);
 277         affs_free_prealloc(inode);
 278         cache_page = (unsigned long)AFFS_I(inode)->i_lc;
 279         if (cache_page) {
 280                 pr_debug("freeing ext cache\n");
 281                 AFFS_I(inode)->i_lc = NULL;
 282                 AFFS_I(inode)->i_ac = NULL;
 283                 free_page(cache_page);
 284         }
 285         affs_brelse(AFFS_I(inode)->i_ext_bh);
 286         AFFS_I(inode)->i_ext_last = ~1;
 287         AFFS_I(inode)->i_ext_bh = NULL;
 288
 289         if (!inode->i_nlink)
 290                 affs_free_block(inode->i_sb, inode->i_ino);
 291 }
 292
 293 struct inode *
 294 affs_new_inode(struct inode *dir)
 295 {
 296         struct super_block      *sb = dir->i_sb;
 297         struct inode            *inode;
 298         u32                      block;
 299         struct buffer_head      *bh;
 300
 301         if (!(inode = new_inode(sb)))
 302                 goto err_inode;
 303
 304         if (!(block = affs_alloc_block(dir, dir->i_ino)))
 305                 goto err_block;
 306
 307         bh = affs_getzeroblk(sb, block);
 308         if (!bh)
 309                 goto err_bh;
 310         mark_buffer_dirty_inode(bh, inode);
 311         affs_brelse(bh);
 312
 313         inode->i_uid     = current_fsuid();
 314         inode->i_gid     = current_fsgid();
 315         inode->i_ino     = block;
 316         set_nlink(inode, 1);
 317         inode->i_mtime   = inode->i_atime = inode->i_ctime = current_time(inode);
 318         atomic_set(&AFFS_I(inode)->i_opencnt, 0);
 319         AFFS_I(inode)->i_blkcnt = 0;
 320         AFFS_I(inode)->i_lc = NULL;
 321         AFFS_I(inode)->i_lc_size = 0;
 322         AFFS_I(inode)->i_lc_shift = 0;
 323         AFFS_I(inode)->i_lc_mask = 0;
 324         AFFS_I(inode)->i_ac = NULL;
 325         AFFS_I(inode)->i_ext_bh = NULL;
 326         AFFS_I(inode)->mmu_private = 0;
 327         AFFS_I(inode)->i_protect = 0;
 328         AFFS_I(inode)->i_lastalloc = 0;
 329         AFFS_I(inode)->i_pa_cnt = 0;
 330         AFFS_I(inode)->i_extcnt = 1;
 331         AFFS_I(inode)->i_ext_last = ~1;
 332
 333         insert_inode_hash(inode);
 334
 335         return inode;
 336
 337 err_bh:
 338         affs_free_block(sb, block);
 339 err_block:
 340         iput(inode);
 341 err_inode:
 342         return NULL;
 343 }
 344
 345 /*
 346  * Add an entry to a directory. Create the header block
 347  * and insert it into the hash table.
 348  */
 349
 350 int
 351 affs_add_entry(struct inode *dir, struct inode *inode, struct dentry *dentry, s32 type)
 352 {
 353         struct super_block *sb = dir->i_sb;
 354         struct buffer_head *inode_bh = NULL;
 355         struct buffer_head *bh;
 356         u32 block = 0;
 357         int retval;
 358
 359         pr_debug("%s(dir=%lu, inode=%lu, \"%pd\", type=%d)\n", __func__,
 360                  dir->i_ino, inode->i_ino, dentry, type);
 361
 362         retval = -EIO;
 363         bh = affs_bread(sb, inode->i_ino);
 364         if (!bh)
 365                 goto done;
 366
 367         affs_lock_link(inode);
 368         switch (type) {
 369         case ST_LINKFILE:
 370         case ST_LINKDIR:
 371                 retval = -ENOSPC;
 372                 block = affs_alloc_block(dir, dir->i_ino);
 373                 if (!block)
 374                         goto err;
 375                 retval = -EIO;
 376                 inode_bh = bh;
 377                 bh = affs_getzeroblk(sb, block);
 378                 if (!bh)
 379                         goto err;
 380                 break;
 381         default:
 382                 break;
 383         }
 384
 385         AFFS_HEAD(bh)->ptype = cpu_to_be32(T_SHORT);
 386         AFFS_HEAD(bh)->key = cpu_to_be32(bh->b_blocknr);
 387         affs_copy_name(AFFS_TAIL(sb, bh)->name, dentry);
 388         AFFS_TAIL(sb, bh)->stype = cpu_to_be32(type);
 389         AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
 390
 391         if (inode_bh) {
 392                 __be32 chain;
 393                 chain = AFFS_TAIL(sb, inode_bh)->link_chain;
 394                 AFFS_TAIL(sb, bh)->original = cpu_to_be32(inode->i_ino);
 395                 AFFS_TAIL(sb, bh)->link_chain = chain;
 396                 AFFS_TAIL(sb, inode_bh)->link_chain = cpu_to_be32(block);
 397                 affs_adjust_checksum(inode_bh, block - be32_to_cpu(chain));
 398                 mark_buffer_dirty_inode(inode_bh, inode);
 399                 set_nlink(inode, 2);
 400                 ihold(inode);
 401         }
 402         affs_fix_checksum(sb, bh);
 403         mark_buffer_dirty_inode(bh, inode);
 404         dentry->d_fsdata = (void *)(long)bh->b_blocknr;
 405
 406         affs_lock_dir(dir);
 407         retval = affs_insert_hash(dir, bh);
 408         mark_buffer_dirty_inode(bh, inode);
 409         affs_unlock_dir(dir);
 410         affs_unlock_link(inode);
 411
 412         d_instantiate(dentry, inode);
 413 done:
 414         affs_brelse(inode_bh);
 415         affs_brelse(bh);
 416         return retval;
 417 err:
 418         if (block)
 419                 affs_free_block(sb, block);
 420         affs_unlock_link(inode);
 421         goto done;
 422 }