linux/fs/affs/inode.c
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   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
  18struct 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
 163bad_inode:
 164        affs_brelse(bh);
 165        iget_failed(inode);
 166        return ERR_PTR(-EIO);
 167}
 168
 169int
 170affs_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
 218int
 219affs_notify_change(struct dentry *dentry, struct iattr *attr)
 220{
 221        struct inode *inode = d_inode(dentry);
 222        int error;
 223
 224        pr_debug("notify_change(%lu,0x%x)\n", inode->i_ino, attr->ia_valid);
 225
 226        error = setattr_prepare(dentry, attr);
 227        if (error)
 228                goto out;
 229
 230        if (((attr->ia_valid & ATTR_UID) &&
 231              affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_SETUID)) ||
 232            ((attr->ia_valid & ATTR_GID) &&
 233              affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_SETGID)) ||
 234            ((attr->ia_valid & ATTR_MODE) &&
 235             (AFFS_SB(inode->i_sb)->s_flags &
 236              (AFFS_MOUNT_SF_SETMODE | AFFS_MOUNT_SF_IMMUTABLE)))) {
 237                if (!affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_QUIET))
 238                        error = -EPERM;
 239                goto out;
 240        }
 241
 242        if ((attr->ia_valid & ATTR_SIZE) &&
 243            attr->ia_size != i_size_read(inode)) {
 244                error = inode_newsize_ok(inode, attr->ia_size);
 245                if (error)
 246                        return error;
 247
 248                truncate_setsize(inode, attr->ia_size);
 249                affs_truncate(inode);
 250        }
 251
 252        setattr_copy(inode, attr);
 253        mark_inode_dirty(inode);
 254
 255        if (attr->ia_valid & ATTR_MODE)
 256                affs_mode_to_prot(inode);
 257out:
 258        return error;
 259}
 260
 261void
 262affs_evict_inode(struct inode *inode)
 263{
 264        unsigned long cache_page;
 265        pr_debug("evict_inode(ino=%lu, nlink=%u)\n",
 266                 inode->i_ino, inode->i_nlink);
 267        truncate_inode_pages_final(&inode->i_data);
 268
 269        if (!inode->i_nlink) {
 270                inode->i_size = 0;
 271                affs_truncate(inode);
 272        }
 273
 274        invalidate_inode_buffers(inode);
 275        clear_inode(inode);
 276        affs_free_prealloc(inode);
 277        cache_page = (unsigned long)AFFS_I(inode)->i_lc;
 278        if (cache_page) {
 279                pr_debug("freeing ext cache\n");
 280                AFFS_I(inode)->i_lc = NULL;
 281                AFFS_I(inode)->i_ac = NULL;
 282                free_page(cache_page);
 283        }
 284        affs_brelse(AFFS_I(inode)->i_ext_bh);
 285        AFFS_I(inode)->i_ext_last = ~1;
 286        AFFS_I(inode)->i_ext_bh = NULL;
 287
 288        if (!inode->i_nlink)
 289                affs_free_block(inode->i_sb, inode->i_ino);
 290}
 291
 292struct inode *
 293affs_new_inode(struct inode *dir)
 294{
 295        struct super_block      *sb = dir->i_sb;
 296        struct inode            *inode;
 297        u32                      block;
 298        struct buffer_head      *bh;
 299
 300        if (!(inode = new_inode(sb)))
 301                goto err_inode;
 302
 303        if (!(block = affs_alloc_block(dir, dir->i_ino)))
 304                goto err_block;
 305
 306        bh = affs_getzeroblk(sb, block);
 307        if (!bh)
 308                goto err_bh;
 309        mark_buffer_dirty_inode(bh, inode);
 310        affs_brelse(bh);
 311
 312        inode->i_uid     = current_fsuid();
 313        inode->i_gid     = current_fsgid();
 314        inode->i_ino     = block;
 315        set_nlink(inode, 1);
 316        inode->i_mtime   = inode->i_atime = inode->i_ctime = current_time(inode);
 317        atomic_set(&AFFS_I(inode)->i_opencnt, 0);
 318        AFFS_I(inode)->i_blkcnt = 0;
 319        AFFS_I(inode)->i_lc = NULL;
 320        AFFS_I(inode)->i_lc_size = 0;
 321        AFFS_I(inode)->i_lc_shift = 0;
 322        AFFS_I(inode)->i_lc_mask = 0;
 323        AFFS_I(inode)->i_ac = NULL;
 324        AFFS_I(inode)->i_ext_bh = NULL;
 325        AFFS_I(inode)->mmu_private = 0;
 326        AFFS_I(inode)->i_protect = 0;
 327        AFFS_I(inode)->i_lastalloc = 0;
 328        AFFS_I(inode)->i_pa_cnt = 0;
 329        AFFS_I(inode)->i_extcnt = 1;
 330        AFFS_I(inode)->i_ext_last = ~1;
 331
 332        insert_inode_hash(inode);
 333
 334        return inode;
 335
 336err_bh:
 337        affs_free_block(sb, block);
 338err_block:
 339        iput(inode);
 340err_inode:
 341        return NULL;
 342}
 343
 344/*
 345 * Add an entry to a directory. Create the header block
 346 * and insert it into the hash table.
 347 */
 348
 349int
 350affs_add_entry(struct inode *dir, struct inode *inode, struct dentry *dentry, s32 type)
 351{
 352        struct super_block *sb = dir->i_sb;
 353        struct buffer_head *inode_bh = NULL;
 354        struct buffer_head *bh;
 355        u32 block = 0;
 356        int retval;
 357
 358        pr_debug("%s(dir=%lu, inode=%lu, \"%pd\", type=%d)\n", __func__,
 359                 dir->i_ino, inode->i_ino, dentry, type);
 360
 361        retval = -EIO;
 362        bh = affs_bread(sb, inode->i_ino);
 363        if (!bh)
 364                goto done;
 365
 366        affs_lock_link(inode);
 367        switch (type) {
 368        case ST_LINKFILE:
 369        case ST_LINKDIR:
 370                retval = -ENOSPC;
 371                block = affs_alloc_block(dir, dir->i_ino);
 372                if (!block)
 373                        goto err;
 374                retval = -EIO;
 375                inode_bh = bh;
 376                bh = affs_getzeroblk(sb, block);
 377                if (!bh)
 378                        goto err;
 379                break;
 380        default:
 381                break;
 382        }
 383
 384        AFFS_HEAD(bh)->ptype = cpu_to_be32(T_SHORT);
 385        AFFS_HEAD(bh)->key = cpu_to_be32(bh->b_blocknr);
 386        affs_copy_name(AFFS_TAIL(sb, bh)->name, dentry);
 387        AFFS_TAIL(sb, bh)->stype = cpu_to_be32(type);
 388        AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
 389
 390        if (inode_bh) {
 391                __be32 chain;
 392                chain = AFFS_TAIL(sb, inode_bh)->link_chain;
 393                AFFS_TAIL(sb, bh)->original = cpu_to_be32(inode->i_ino);
 394                AFFS_TAIL(sb, bh)->link_chain = chain;
 395                AFFS_TAIL(sb, inode_bh)->link_chain = cpu_to_be32(block);
 396                affs_adjust_checksum(inode_bh, block - be32_to_cpu(chain));
 397                mark_buffer_dirty_inode(inode_bh, inode);
 398                set_nlink(inode, 2);
 399                ihold(inode);
 400        }
 401        affs_fix_checksum(sb, bh);
 402        mark_buffer_dirty_inode(bh, inode);
 403        dentry->d_fsdata = (void *)(long)bh->b_blocknr;
 404
 405        affs_lock_dir(dir);
 406        retval = affs_insert_hash(dir, bh);
 407        mark_buffer_dirty_inode(bh, inode);
 408        affs_unlock_dir(dir);
 409        affs_unlock_link(inode);
 410
 411        d_instantiate(dentry, inode);
 412done:
 413        affs_brelse(inode_bh);
 414        affs_brelse(bh);
 415        return retval;
 416err:
 417        if (block)
 418                affs_free_block(sb, block);
 419        affs_unlock_link(inode);
 420        goto done;
 421}
 422