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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * linux/fs/affs/inode.c4 *5 * (c) 1996 Hans-Joachim Widmaier - Rewritten6 *7 * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.8 *9 * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.10 *11 * (C) 1991 Linus Torvalds - minix filesystem12 */13 14#include <linux/module.h>15#include <linux/init.h>16#include <linux/statfs.h>17#include <linux/parser.h>18#include <linux/magic.h>19#include <linux/sched.h>20#include <linux/cred.h>21#include <linux/slab.h>22#include <linux/writeback.h>23#include <linux/blkdev.h>24#include <linux/seq_file.h>25#include <linux/iversion.h>26#include "affs.h"27 28static int affs_statfs(struct dentry *dentry, struct kstatfs *buf);29static int affs_show_options(struct seq_file *m, struct dentry *root);30static int affs_remount (struct super_block *sb, int *flags, char *data);31 32static void33affs_commit_super(struct super_block *sb, int wait)34{35 struct affs_sb_info *sbi = AFFS_SB(sb);36 struct buffer_head *bh = sbi->s_root_bh;37 struct affs_root_tail *tail = AFFS_ROOT_TAIL(sb, bh);38 39 lock_buffer(bh);40 affs_secs_to_datestamp(ktime_get_real_seconds(), &tail->disk_change);41 affs_fix_checksum(sb, bh);42 unlock_buffer(bh);43 44 mark_buffer_dirty(bh);45 if (wait)46 sync_dirty_buffer(bh);47}48 49static void50affs_put_super(struct super_block *sb)51{52 struct affs_sb_info *sbi = AFFS_SB(sb);53 pr_debug("%s()\n", __func__);54 55 cancel_delayed_work_sync(&sbi->sb_work);56}57 58static int59affs_sync_fs(struct super_block *sb, int wait)60{61 affs_commit_super(sb, wait);62 return 0;63}64 65static void flush_superblock(struct work_struct *work)66{67 struct affs_sb_info *sbi;68 struct super_block *sb;69 70 sbi = container_of(work, struct affs_sb_info, sb_work.work);71 sb = sbi->sb;72 73 spin_lock(&sbi->work_lock);74 sbi->work_queued = 0;75 spin_unlock(&sbi->work_lock);76 77 affs_commit_super(sb, 1);78}79 80void affs_mark_sb_dirty(struct super_block *sb)81{82 struct affs_sb_info *sbi = AFFS_SB(sb);83 unsigned long delay;84 85 if (sb_rdonly(sb))86 return;87 88 spin_lock(&sbi->work_lock);89 if (!sbi->work_queued) {90 delay = msecs_to_jiffies(dirty_writeback_interval * 10);91 queue_delayed_work(system_long_wq, &sbi->sb_work, delay);92 sbi->work_queued = 1;93 }94 spin_unlock(&sbi->work_lock);95}96 97static struct kmem_cache * affs_inode_cachep;98 99static struct inode *affs_alloc_inode(struct super_block *sb)100{101 struct affs_inode_info *i;102 103 i = alloc_inode_sb(sb, affs_inode_cachep, GFP_KERNEL);104 if (!i)105 return NULL;106 107 inode_set_iversion(&i->vfs_inode, 1);108 i->i_lc = NULL;109 i->i_ext_bh = NULL;110 i->i_pa_cnt = 0;111 112 return &i->vfs_inode;113}114 115static void affs_free_inode(struct inode *inode)116{117 kmem_cache_free(affs_inode_cachep, AFFS_I(inode));118}119 120static void init_once(void *foo)121{122 struct affs_inode_info *ei = (struct affs_inode_info *) foo;123 124 mutex_init(&ei->i_link_lock);125 mutex_init(&ei->i_ext_lock);126 inode_init_once(&ei->vfs_inode);127}128 129static int __init init_inodecache(void)130{131 affs_inode_cachep = kmem_cache_create("affs_inode_cache",132 sizeof(struct affs_inode_info),133 0, (SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT),134 init_once);135 if (affs_inode_cachep == NULL)136 return -ENOMEM;137 return 0;138}139 140static void destroy_inodecache(void)141{142 /*143 * Make sure all delayed rcu free inodes are flushed before we144 * destroy cache.145 */146 rcu_barrier();147 kmem_cache_destroy(affs_inode_cachep);148}149 150static const struct super_operations affs_sops = {151 .alloc_inode = affs_alloc_inode,152 .free_inode = affs_free_inode,153 .write_inode = affs_write_inode,154 .evict_inode = affs_evict_inode,155 .put_super = affs_put_super,156 .sync_fs = affs_sync_fs,157 .statfs = affs_statfs,158 .remount_fs = affs_remount,159 .show_options = affs_show_options,160};161 162enum {163 Opt_bs, Opt_mode, Opt_mufs, Opt_notruncate, Opt_prefix, Opt_protect,164 Opt_reserved, Opt_root, Opt_setgid, Opt_setuid,165 Opt_verbose, Opt_volume, Opt_ignore, Opt_err,166};167 168static const match_table_t tokens = {169 {Opt_bs, "bs=%u"},170 {Opt_mode, "mode=%o"},171 {Opt_mufs, "mufs"},172 {Opt_notruncate, "nofilenametruncate"},173 {Opt_prefix, "prefix=%s"},174 {Opt_protect, "protect"},175 {Opt_reserved, "reserved=%u"},176 {Opt_root, "root=%u"},177 {Opt_setgid, "setgid=%u"},178 {Opt_setuid, "setuid=%u"},179 {Opt_verbose, "verbose"},180 {Opt_volume, "volume=%s"},181 {Opt_ignore, "grpquota"},182 {Opt_ignore, "noquota"},183 {Opt_ignore, "quota"},184 {Opt_ignore, "usrquota"},185 {Opt_err, NULL},186};187 188static int189parse_options(char *options, kuid_t *uid, kgid_t *gid, int *mode, int *reserved, s32 *root,190 int *blocksize, char **prefix, char *volume, unsigned long *mount_opts)191{192 char *p;193 substring_t args[MAX_OPT_ARGS];194 195 /* Fill in defaults */196 197 *uid = current_uid();198 *gid = current_gid();199 *reserved = 2;200 *root = -1;201 *blocksize = -1;202 volume[0] = ':';203 volume[1] = 0;204 *mount_opts = 0;205 if (!options)206 return 1;207 208 while ((p = strsep(&options, ",")) != NULL) {209 int token, n, option;210 if (!*p)211 continue;212 213 token = match_token(p, tokens, args);214 switch (token) {215 case Opt_bs:216 if (match_int(&args[0], &n))217 return 0;218 if (n != 512 && n != 1024 && n != 2048219 && n != 4096) {220 pr_warn("Invalid blocksize (512, 1024, 2048, 4096 allowed)\n");221 return 0;222 }223 *blocksize = n;224 break;225 case Opt_mode:226 if (match_octal(&args[0], &option))227 return 0;228 *mode = option & 0777;229 affs_set_opt(*mount_opts, SF_SETMODE);230 break;231 case Opt_mufs:232 affs_set_opt(*mount_opts, SF_MUFS);233 break;234 case Opt_notruncate:235 affs_set_opt(*mount_opts, SF_NO_TRUNCATE);236 break;237 case Opt_prefix:238 kfree(*prefix);239 *prefix = match_strdup(&args[0]);240 if (!*prefix)241 return 0;242 affs_set_opt(*mount_opts, SF_PREFIX);243 break;244 case Opt_protect:245 affs_set_opt(*mount_opts, SF_IMMUTABLE);246 break;247 case Opt_reserved:248 if (match_int(&args[0], reserved))249 return 0;250 break;251 case Opt_root:252 if (match_int(&args[0], root))253 return 0;254 break;255 case Opt_setgid:256 if (match_int(&args[0], &option))257 return 0;258 *gid = make_kgid(current_user_ns(), option);259 if (!gid_valid(*gid))260 return 0;261 affs_set_opt(*mount_opts, SF_SETGID);262 break;263 case Opt_setuid:264 if (match_int(&args[0], &option))265 return 0;266 *uid = make_kuid(current_user_ns(), option);267 if (!uid_valid(*uid))268 return 0;269 affs_set_opt(*mount_opts, SF_SETUID);270 break;271 case Opt_verbose:272 affs_set_opt(*mount_opts, SF_VERBOSE);273 break;274 case Opt_volume: {275 char *vol = match_strdup(&args[0]);276 if (!vol)277 return 0;278 strscpy(volume, vol, 32);279 kfree(vol);280 break;281 }282 case Opt_ignore:283 /* Silently ignore the quota options */284 break;285 default:286 pr_warn("Unrecognized mount option \"%s\" or missing value\n",287 p);288 return 0;289 }290 }291 return 1;292}293 294static int affs_show_options(struct seq_file *m, struct dentry *root)295{296 struct super_block *sb = root->d_sb;297 struct affs_sb_info *sbi = AFFS_SB(sb);298 299 if (sb->s_blocksize)300 seq_printf(m, ",bs=%lu", sb->s_blocksize);301 if (affs_test_opt(sbi->s_flags, SF_SETMODE))302 seq_printf(m, ",mode=%o", sbi->s_mode);303 if (affs_test_opt(sbi->s_flags, SF_MUFS))304 seq_puts(m, ",mufs");305 if (affs_test_opt(sbi->s_flags, SF_NO_TRUNCATE))306 seq_puts(m, ",nofilenametruncate");307 if (affs_test_opt(sbi->s_flags, SF_PREFIX))308 seq_printf(m, ",prefix=%s", sbi->s_prefix);309 if (affs_test_opt(sbi->s_flags, SF_IMMUTABLE))310 seq_puts(m, ",protect");311 if (sbi->s_reserved != 2)312 seq_printf(m, ",reserved=%u", sbi->s_reserved);313 if (sbi->s_root_block != (sbi->s_reserved + sbi->s_partition_size - 1) / 2)314 seq_printf(m, ",root=%u", sbi->s_root_block);315 if (affs_test_opt(sbi->s_flags, SF_SETGID))316 seq_printf(m, ",setgid=%u",317 from_kgid_munged(&init_user_ns, sbi->s_gid));318 if (affs_test_opt(sbi->s_flags, SF_SETUID))319 seq_printf(m, ",setuid=%u",320 from_kuid_munged(&init_user_ns, sbi->s_uid));321 if (affs_test_opt(sbi->s_flags, SF_VERBOSE))322 seq_puts(m, ",verbose");323 if (sbi->s_volume[0])324 seq_printf(m, ",volume=%s", sbi->s_volume);325 return 0;326}327 328/* This function definitely needs to be split up. Some fine day I'll329 * hopefully have the guts to do so. Until then: sorry for the mess.330 */331 332static int affs_fill_super(struct super_block *sb, void *data, int silent)333{334 struct affs_sb_info *sbi;335 struct buffer_head *root_bh = NULL;336 struct buffer_head *boot_bh;337 struct inode *root_inode = NULL;338 s32 root_block;339 int size, blocksize;340 u32 chksum;341 int num_bm;342 int i, j;343 kuid_t uid;344 kgid_t gid;345 int reserved;346 unsigned long mount_flags;347 int tmp_flags; /* fix remount prototype... */348 u8 sig[4];349 int ret;350 351 pr_debug("read_super(%s)\n", data ? (const char *)data : "no options");352 353 sb->s_magic = AFFS_SUPER_MAGIC;354 sb->s_op = &affs_sops;355 sb->s_flags |= SB_NODIRATIME;356 357 sb->s_time_gran = NSEC_PER_SEC;358 sb->s_time_min = sys_tz.tz_minuteswest * 60 + AFFS_EPOCH_DELTA;359 sb->s_time_max = 86400LL * U32_MAX + 86400 + sb->s_time_min;360 361 sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL);362 if (!sbi)363 return -ENOMEM;364 365 sb->s_fs_info = sbi;366 sbi->sb = sb;367 mutex_init(&sbi->s_bmlock);368 spin_lock_init(&sbi->symlink_lock);369 spin_lock_init(&sbi->work_lock);370 INIT_DELAYED_WORK(&sbi->sb_work, flush_superblock);371 372 if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block,373 &blocksize,&sbi->s_prefix,374 sbi->s_volume, &mount_flags)) {375 pr_err("Error parsing options\n");376 return -EINVAL;377 }378 /* N.B. after this point s_prefix must be released */379 380 sbi->s_flags = mount_flags;381 sbi->s_mode = i;382 sbi->s_uid = uid;383 sbi->s_gid = gid;384 sbi->s_reserved= reserved;385 386 /* Get the size of the device in 512-byte blocks.387 * If we later see that the partition uses bigger388 * blocks, we will have to change it.389 */390 391 size = bdev_nr_sectors(sb->s_bdev);392 pr_debug("initial blocksize=%d, #blocks=%d\n", 512, size);393 394 affs_set_blocksize(sb, PAGE_SIZE);395 /* Try to find root block. Its location depends on the block size. */396 397 i = bdev_logical_block_size(sb->s_bdev);398 j = PAGE_SIZE;399 if (blocksize > 0) {400 i = j = blocksize;401 size = size / (blocksize / 512);402 }403 404 for (blocksize = i; blocksize <= j; blocksize <<= 1, size >>= 1) {405 sbi->s_root_block = root_block;406 if (root_block < 0)407 sbi->s_root_block = (reserved + size - 1) / 2;408 pr_debug("setting blocksize to %d\n", blocksize);409 affs_set_blocksize(sb, blocksize);410 sbi->s_partition_size = size;411 412 /* The root block location that was calculated above is not413 * correct if the partition size is an odd number of 512-414 * byte blocks, which will be rounded down to a number of415 * 1024-byte blocks, and if there were an even number of416 * reserved blocks. Ideally, all partition checkers should417 * report the real number of blocks of the real blocksize,418 * but since this just cannot be done, we have to try to419 * find the root block anyways. In the above case, it is one420 * block behind the calculated one. So we check this one, too.421 */422 for (num_bm = 0; num_bm < 2; num_bm++) {423 pr_debug("Dev %s, trying root=%u, bs=%d, "424 "size=%d, reserved=%d\n",425 sb->s_id,426 sbi->s_root_block + num_bm,427 blocksize, size, reserved);428 root_bh = affs_bread(sb, sbi->s_root_block + num_bm);429 if (!root_bh)430 continue;431 if (!affs_checksum_block(sb, root_bh) &&432 be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT &&433 be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) {434 sbi->s_hashsize = blocksize / 4 - 56;435 sbi->s_root_block += num_bm;436 goto got_root;437 }438 affs_brelse(root_bh);439 root_bh = NULL;440 }441 }442 if (!silent)443 pr_err("No valid root block on device %s\n", sb->s_id);444 return -EINVAL;445 446 /* N.B. after this point bh must be released */447got_root:448 /* Keep super block in cache */449 sbi->s_root_bh = root_bh;450 root_block = sbi->s_root_block;451 452 /* Find out which kind of FS we have */453 boot_bh = sb_bread(sb, 0);454 if (!boot_bh) {455 pr_err("Cannot read boot block\n");456 return -EINVAL;457 }458 memcpy(sig, boot_bh->b_data, 4);459 brelse(boot_bh);460 chksum = be32_to_cpu(*(__be32 *)sig);461 462 /* Dircache filesystems are compatible with non-dircache ones463 * when reading. As long as they aren't supported, writing is464 * not recommended.465 */466 if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS467 || chksum == MUFS_DCOFS) && !sb_rdonly(sb)) {468 pr_notice("Dircache FS - mounting %s read only\n", sb->s_id);469 sb->s_flags |= SB_RDONLY;470 }471 switch (chksum) {472 case MUFS_FS:473 case MUFS_INTLFFS:474 case MUFS_DCFFS:475 affs_set_opt(sbi->s_flags, SF_MUFS);476 fallthrough;477 case FS_INTLFFS:478 case FS_DCFFS:479 affs_set_opt(sbi->s_flags, SF_INTL);480 break;481 case MUFS_FFS:482 affs_set_opt(sbi->s_flags, SF_MUFS);483 break;484 case FS_FFS:485 break;486 case MUFS_OFS:487 affs_set_opt(sbi->s_flags, SF_MUFS);488 fallthrough;489 case FS_OFS:490 affs_set_opt(sbi->s_flags, SF_OFS);491 sb->s_flags |= SB_NOEXEC;492 break;493 case MUFS_DCOFS:494 case MUFS_INTLOFS:495 affs_set_opt(sbi->s_flags, SF_MUFS);496 fallthrough;497 case FS_DCOFS:498 case FS_INTLOFS:499 affs_set_opt(sbi->s_flags, SF_INTL);500 affs_set_opt(sbi->s_flags, SF_OFS);501 sb->s_flags |= SB_NOEXEC;502 break;503 default:504 pr_err("Unknown filesystem on device %s: %08X\n",505 sb->s_id, chksum);506 return -EINVAL;507 }508 509 if (affs_test_opt(mount_flags, SF_VERBOSE)) {510 u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0];511 pr_notice("Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n",512 len > 31 ? 31 : len,513 AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1,514 sig, sig[3] + '0', blocksize);515 }516 517 sb->s_flags |= SB_NODEV | SB_NOSUID;518 519 sbi->s_data_blksize = sb->s_blocksize;520 if (affs_test_opt(sbi->s_flags, SF_OFS))521 sbi->s_data_blksize -= 24;522 523 tmp_flags = sb->s_flags;524 ret = affs_init_bitmap(sb, &tmp_flags);525 if (ret)526 return ret;527 sb->s_flags = tmp_flags;528 529 /* set up enough so that it can read an inode */530 531 root_inode = affs_iget(sb, root_block);532 if (IS_ERR(root_inode))533 return PTR_ERR(root_inode);534 535 if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_INTL))536 sb->s_d_op = &affs_intl_dentry_operations;537 else538 sb->s_d_op = &affs_dentry_operations;539 540 sb->s_root = d_make_root(root_inode);541 if (!sb->s_root) {542 pr_err("AFFS: Get root inode failed\n");543 return -ENOMEM;544 }545 546 sb->s_export_op = &affs_export_ops;547 pr_debug("s_flags=%lX\n", sb->s_flags);548 return 0;549}550 551static int552affs_remount(struct super_block *sb, int *flags, char *data)553{554 struct affs_sb_info *sbi = AFFS_SB(sb);555 int blocksize;556 kuid_t uid;557 kgid_t gid;558 int mode;559 int reserved;560 int root_block;561 unsigned long mount_flags;562 int res = 0;563 char volume[32];564 char *prefix = NULL;565 566 pr_debug("%s(flags=0x%x,opts=\"%s\")\n", __func__, *flags, data);567 568 sync_filesystem(sb);569 *flags |= SB_NODIRATIME;570 571 memcpy(volume, sbi->s_volume, 32);572 if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block,573 &blocksize, &prefix, volume,574 &mount_flags)) {575 kfree(prefix);576 return -EINVAL;577 }578 579 flush_delayed_work(&sbi->sb_work);580 581 sbi->s_flags = mount_flags;582 sbi->s_mode = mode;583 sbi->s_uid = uid;584 sbi->s_gid = gid;585 /* protect against readers */586 spin_lock(&sbi->symlink_lock);587 if (prefix) {588 kfree(sbi->s_prefix);589 sbi->s_prefix = prefix;590 }591 memcpy(sbi->s_volume, volume, 32);592 spin_unlock(&sbi->symlink_lock);593 594 if ((bool)(*flags & SB_RDONLY) == sb_rdonly(sb))595 return 0;596 597 if (*flags & SB_RDONLY)598 affs_free_bitmap(sb);599 else600 res = affs_init_bitmap(sb, flags);601 602 return res;603}604 605static int606affs_statfs(struct dentry *dentry, struct kstatfs *buf)607{608 struct super_block *sb = dentry->d_sb;609 int free;610 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);611 612 pr_debug("%s() partsize=%d, reserved=%d\n",613 __func__, AFFS_SB(sb)->s_partition_size,614 AFFS_SB(sb)->s_reserved);615 616 free = affs_count_free_blocks(sb);617 buf->f_type = AFFS_SUPER_MAGIC;618 buf->f_bsize = sb->s_blocksize;619 buf->f_blocks = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved;620 buf->f_bfree = free;621 buf->f_bavail = free;622 buf->f_fsid = u64_to_fsid(id);623 buf->f_namelen = AFFSNAMEMAX;624 return 0;625}626 627static struct dentry *affs_mount(struct file_system_type *fs_type,628 int flags, const char *dev_name, void *data)629{630 return mount_bdev(fs_type, flags, dev_name, data, affs_fill_super);631}632 633static void affs_kill_sb(struct super_block *sb)634{635 struct affs_sb_info *sbi = AFFS_SB(sb);636 kill_block_super(sb);637 if (sbi) {638 affs_free_bitmap(sb);639 affs_brelse(sbi->s_root_bh);640 kfree(sbi->s_prefix);641 mutex_destroy(&sbi->s_bmlock);642 kfree_rcu(sbi, rcu);643 }644}645 646static struct file_system_type affs_fs_type = {647 .owner = THIS_MODULE,648 .name = "affs",649 .mount = affs_mount,650 .kill_sb = affs_kill_sb,651 .fs_flags = FS_REQUIRES_DEV,652};653MODULE_ALIAS_FS("affs");654 655static int __init init_affs_fs(void)656{657 int err = init_inodecache();658 if (err)659 goto out1;660 err = register_filesystem(&affs_fs_type);661 if (err)662 goto out;663 return 0;664out:665 destroy_inodecache();666out1:667 return err;668}669 670static void __exit exit_affs_fs(void)671{672 unregister_filesystem(&affs_fs_type);673 destroy_inodecache();674}675 676MODULE_DESCRIPTION("Amiga filesystem support for Linux");677MODULE_LICENSE("GPL");678 679module_init(init_affs_fs)680module_exit(exit_affs_fs)681