// SPDX-License-Identifier: GPL-2.0-only /* * linux/fs/affs/inode.c * * (c) 1996 Hans-Joachim Widmaier - Rewritten * * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem. * * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem. * * (C) 1991 Linus Torvalds - minix filesystem */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "affs.h" static int affs_statfs(struct dentry *dentry, struct kstatfs *buf); static int affs_show_options(struct seq_file *m, struct dentry *root); static void affs_commit_super(struct super_block *sb, int wait) { struct affs_sb_info *sbi = AFFS_SB(sb); struct buffer_head *bh = sbi->s_root_bh; struct affs_root_tail *tail = AFFS_ROOT_TAIL(sb, bh); lock_buffer(bh); affs_secs_to_datestamp(ktime_get_real_seconds(), &tail->disk_change); affs_fix_checksum(sb, bh); unlock_buffer(bh); mark_buffer_dirty(bh); if (wait) sync_dirty_buffer(bh); } static void affs_put_super(struct super_block *sb) { struct affs_sb_info *sbi = AFFS_SB(sb); pr_debug("%s()\n", __func__); cancel_delayed_work_sync(&sbi->sb_work); } static int affs_sync_fs(struct super_block *sb, int wait) { affs_commit_super(sb, wait); return 0; } static void flush_superblock(struct work_struct *work) { struct affs_sb_info *sbi; struct super_block *sb; sbi = container_of(work, struct affs_sb_info, sb_work.work); sb = sbi->sb; spin_lock(&sbi->work_lock); sbi->work_queued = 0; spin_unlock(&sbi->work_lock); affs_commit_super(sb, 1); } void affs_mark_sb_dirty(struct super_block *sb) { struct affs_sb_info *sbi = AFFS_SB(sb); unsigned long delay; if (sb_rdonly(sb)) return; spin_lock(&sbi->work_lock); if (!sbi->work_queued) { delay = msecs_to_jiffies(dirty_writeback_interval * 10); queue_delayed_work(system_long_wq, &sbi->sb_work, delay); sbi->work_queued = 1; } spin_unlock(&sbi->work_lock); } static struct kmem_cache * affs_inode_cachep; static struct inode *affs_alloc_inode(struct super_block *sb) { struct affs_inode_info *i; i = alloc_inode_sb(sb, affs_inode_cachep, GFP_KERNEL); if (!i) return NULL; inode_set_iversion(&i->vfs_inode, 1); i->i_lc = NULL; i->i_ext_bh = NULL; i->i_pa_cnt = 0; return &i->vfs_inode; } static void affs_free_inode(struct inode *inode) { kmem_cache_free(affs_inode_cachep, AFFS_I(inode)); } static void init_once(void *foo) { struct affs_inode_info *ei = (struct affs_inode_info *) foo; mutex_init(&ei->i_link_lock); mutex_init(&ei->i_ext_lock); inode_init_once(&ei->vfs_inode); } static int __init init_inodecache(void) { affs_inode_cachep = kmem_cache_create("affs_inode_cache", sizeof(struct affs_inode_info), 0, (SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT), init_once); if (affs_inode_cachep == NULL) return -ENOMEM; return 0; } static void destroy_inodecache(void) { /* * Make sure all delayed rcu free inodes are flushed before we * destroy cache. */ rcu_barrier(); kmem_cache_destroy(affs_inode_cachep); } static const struct super_operations affs_sops = { .alloc_inode = affs_alloc_inode, .free_inode = affs_free_inode, .write_inode = affs_write_inode, .evict_inode = affs_evict_inode, .put_super = affs_put_super, .sync_fs = affs_sync_fs, .statfs = affs_statfs, .show_options = affs_show_options, }; enum { Opt_bs, Opt_mode, Opt_mufs, Opt_notruncate, Opt_prefix, Opt_protect, Opt_reserved, Opt_root, Opt_setgid, Opt_setuid, Opt_verbose, Opt_volume, Opt_ignore, }; struct affs_context { kuid_t uid; /* uid to override */ kgid_t gid; /* gid to override */ unsigned int mode; /* mode to override */ unsigned int reserved; /* Number of reserved blocks */ int root_block; /* FFS root block number */ int blocksize; /* Initial device blksize */ char *prefix; /* Prefix for volumes and assigns */ char volume[32]; /* Vol. prefix for absolute symlinks */ unsigned long mount_flags; /* Options */ }; static const struct fs_parameter_spec affs_param_spec[] = { fsparam_u32 ("bs", Opt_bs), fsparam_u32oct ("mode", Opt_mode), fsparam_flag ("mufs", Opt_mufs), fsparam_flag ("nofilenametruncate", Opt_notruncate), fsparam_string ("prefix", Opt_prefix), fsparam_flag ("protect", Opt_protect), fsparam_u32 ("reserved", Opt_reserved), fsparam_u32 ("root", Opt_root), fsparam_gid ("setgid", Opt_setgid), fsparam_uid ("setuid", Opt_setuid), fsparam_flag ("verbose", Opt_verbose), fsparam_string ("volume", Opt_volume), fsparam_flag ("grpquota", Opt_ignore), fsparam_flag ("noquota", Opt_ignore), fsparam_flag ("quota", Opt_ignore), fsparam_flag ("usrquota", Opt_ignore), {}, }; static int affs_parse_param(struct fs_context *fc, struct fs_parameter *param) { struct affs_context *ctx = fc->fs_private; struct fs_parse_result result; int n; int opt; opt = fs_parse(fc, affs_param_spec, param, &result); if (opt < 0) return opt; switch (opt) { case Opt_bs: n = result.uint_32; if (n != 512 && n != 1024 && n != 2048 && n != 4096) { pr_warn("Invalid blocksize (512, 1024, 2048, 4096 allowed)\n"); return -EINVAL; } ctx->blocksize = n; break; case Opt_mode: ctx->mode = result.uint_32 & 0777; affs_set_opt(ctx->mount_flags, SF_SETMODE); break; case Opt_mufs: affs_set_opt(ctx->mount_flags, SF_MUFS); break; case Opt_notruncate: affs_set_opt(ctx->mount_flags, SF_NO_TRUNCATE); break; case Opt_prefix: kfree(ctx->prefix); ctx->prefix = param->string; param->string = NULL; affs_set_opt(ctx->mount_flags, SF_PREFIX); break; case Opt_protect: affs_set_opt(ctx->mount_flags, SF_IMMUTABLE); break; case Opt_reserved: ctx->reserved = result.uint_32; break; case Opt_root: ctx->root_block = result.uint_32; break; case Opt_setgid: ctx->gid = result.gid; affs_set_opt(ctx->mount_flags, SF_SETGID); break; case Opt_setuid: ctx->uid = result.uid; affs_set_opt(ctx->mount_flags, SF_SETUID); break; case Opt_verbose: affs_set_opt(ctx->mount_flags, SF_VERBOSE); break; case Opt_volume: strscpy(ctx->volume, param->string, 32); break; case Opt_ignore: /* Silently ignore the quota options */ break; default: return -EINVAL; } return 0; } static int affs_show_options(struct seq_file *m, struct dentry *root) { struct super_block *sb = root->d_sb; struct affs_sb_info *sbi = AFFS_SB(sb); if (sb->s_blocksize) seq_printf(m, ",bs=%lu", sb->s_blocksize); if (affs_test_opt(sbi->s_flags, SF_SETMODE)) seq_printf(m, ",mode=%o", sbi->s_mode); if (affs_test_opt(sbi->s_flags, SF_MUFS)) seq_puts(m, ",mufs"); if (affs_test_opt(sbi->s_flags, SF_NO_TRUNCATE)) seq_puts(m, ",nofilenametruncate"); if (affs_test_opt(sbi->s_flags, SF_PREFIX)) seq_printf(m, ",prefix=%s", sbi->s_prefix); if (affs_test_opt(sbi->s_flags, SF_IMMUTABLE)) seq_puts(m, ",protect"); if (sbi->s_reserved != 2) seq_printf(m, ",reserved=%u", sbi->s_reserved); if (sbi->s_root_block != (sbi->s_reserved + sbi->s_partition_size - 1) / 2) seq_printf(m, ",root=%u", sbi->s_root_block); if (affs_test_opt(sbi->s_flags, SF_SETGID)) seq_printf(m, ",setgid=%u", from_kgid_munged(&init_user_ns, sbi->s_gid)); if (affs_test_opt(sbi->s_flags, SF_SETUID)) seq_printf(m, ",setuid=%u", from_kuid_munged(&init_user_ns, sbi->s_uid)); if (affs_test_opt(sbi->s_flags, SF_VERBOSE)) seq_puts(m, ",verbose"); if (sbi->s_volume[0]) seq_printf(m, ",volume=%s", sbi->s_volume); return 0; } /* This function definitely needs to be split up. Some fine day I'll * hopefully have the guts to do so. Until then: sorry for the mess. */ static int affs_fill_super(struct super_block *sb, struct fs_context *fc) { struct affs_sb_info *sbi; struct affs_context *ctx = fc->fs_private; struct buffer_head *root_bh = NULL; struct buffer_head *boot_bh; struct inode *root_inode = NULL; int silent = fc->sb_flags & SB_SILENT; int size, blocksize; u32 chksum; int num_bm; int i, j; int tmp_flags; /* fix remount prototype... */ u8 sig[4]; int ret; sb->s_magic = AFFS_SUPER_MAGIC; sb->s_op = &affs_sops; sb->s_flags |= SB_NODIRATIME; sb->s_time_gran = NSEC_PER_SEC; sb->s_time_min = sys_tz.tz_minuteswest * 60 + AFFS_EPOCH_DELTA; sb->s_time_max = 86400LL * U32_MAX + 86400 + sb->s_time_min; sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL); if (!sbi) return -ENOMEM; sb->s_fs_info = sbi; sbi->sb = sb; mutex_init(&sbi->s_bmlock); spin_lock_init(&sbi->symlink_lock); spin_lock_init(&sbi->work_lock); INIT_DELAYED_WORK(&sbi->sb_work, flush_superblock); sbi->s_flags = ctx->mount_flags; sbi->s_mode = ctx->mode; sbi->s_uid = ctx->uid; sbi->s_gid = ctx->gid; sbi->s_reserved = ctx->reserved; sbi->s_prefix = ctx->prefix; ctx->prefix = NULL; memcpy(sbi->s_volume, ctx->volume, 32); /* N.B. after this point s_prefix must be released */ /* Get the size of the device in 512-byte blocks. * If we later see that the partition uses bigger * blocks, we will have to change it. */ size = bdev_nr_sectors(sb->s_bdev); pr_debug("initial blocksize=%d, #blocks=%d\n", 512, size); affs_set_blocksize(sb, PAGE_SIZE); /* Try to find root block. Its location depends on the block size. */ i = bdev_logical_block_size(sb->s_bdev); j = PAGE_SIZE; blocksize = ctx->blocksize; if (blocksize > 0) { i = j = blocksize; size = size / (blocksize / 512); } for (blocksize = i; blocksize <= j; blocksize <<= 1, size >>= 1) { sbi->s_root_block = ctx->root_block; if (ctx->root_block < 0) sbi->s_root_block = (ctx->reserved + size - 1) / 2; pr_debug("setting blocksize to %d\n", blocksize); affs_set_blocksize(sb, blocksize); sbi->s_partition_size = size; /* The root block location that was calculated above is not * correct if the partition size is an odd number of 512- * byte blocks, which will be rounded down to a number of * 1024-byte blocks, and if there were an even number of * reserved blocks. Ideally, all partition checkers should * report the real number of blocks of the real blocksize, * but since this just cannot be done, we have to try to * find the root block anyways. In the above case, it is one * block behind the calculated one. So we check this one, too. */ for (num_bm = 0; num_bm < 2; num_bm++) { pr_debug("Dev %s, trying root=%u, bs=%d, " "size=%d, reserved=%d\n", sb->s_id, sbi->s_root_block + num_bm, ctx->blocksize, size, ctx->reserved); root_bh = affs_bread(sb, sbi->s_root_block + num_bm); if (!root_bh) continue; if (!affs_checksum_block(sb, root_bh) && be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT && be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) { sbi->s_hashsize = blocksize / 4 - 56; sbi->s_root_block += num_bm; goto got_root; } affs_brelse(root_bh); root_bh = NULL; } } if (!silent) pr_err("No valid root block on device %s\n", sb->s_id); return -EINVAL; /* N.B. after this point bh must be released */ got_root: /* Keep super block in cache */ sbi->s_root_bh = root_bh; ctx->root_block = sbi->s_root_block; /* Find out which kind of FS we have */ boot_bh = sb_bread(sb, 0); if (!boot_bh) { pr_err("Cannot read boot block\n"); return -EINVAL; } memcpy(sig, boot_bh->b_data, 4); brelse(boot_bh); chksum = be32_to_cpu(*(__be32 *)sig); /* Dircache filesystems are compatible with non-dircache ones * when reading. As long as they aren't supported, writing is * not recommended. */ if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS || chksum == MUFS_DCOFS) && !sb_rdonly(sb)) { pr_notice("Dircache FS - mounting %s read only\n", sb->s_id); sb->s_flags |= SB_RDONLY; } switch (chksum) { case MUFS_FS: case MUFS_INTLFFS: case MUFS_DCFFS: affs_set_opt(sbi->s_flags, SF_MUFS); fallthrough; case FS_INTLFFS: case FS_DCFFS: affs_set_opt(sbi->s_flags, SF_INTL); break; case MUFS_FFS: affs_set_opt(sbi->s_flags, SF_MUFS); break; case FS_FFS: break; case MUFS_OFS: affs_set_opt(sbi->s_flags, SF_MUFS); fallthrough; case FS_OFS: affs_set_opt(sbi->s_flags, SF_OFS); sb->s_flags |= SB_NOEXEC; break; case MUFS_DCOFS: case MUFS_INTLOFS: affs_set_opt(sbi->s_flags, SF_MUFS); fallthrough; case FS_DCOFS: case FS_INTLOFS: affs_set_opt(sbi->s_flags, SF_INTL); affs_set_opt(sbi->s_flags, SF_OFS); sb->s_flags |= SB_NOEXEC; break; default: pr_err("Unknown filesystem on device %s: %08X\n", sb->s_id, chksum); return -EINVAL; } if (affs_test_opt(ctx->mount_flags, SF_VERBOSE)) { u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0]; pr_notice("Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n", len > 31 ? 31 : len, AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1, sig, sig[3] + '0', blocksize); } sb->s_flags |= SB_NODEV | SB_NOSUID; sbi->s_data_blksize = sb->s_blocksize; if (affs_test_opt(sbi->s_flags, SF_OFS)) sbi->s_data_blksize -= 24; tmp_flags = sb->s_flags; ret = affs_init_bitmap(sb, &tmp_flags); if (ret) return ret; sb->s_flags = tmp_flags; /* set up enough so that it can read an inode */ root_inode = affs_iget(sb, ctx->root_block); if (IS_ERR(root_inode)) return PTR_ERR(root_inode); if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_INTL)) sb->s_d_op = &affs_intl_dentry_operations; else sb->s_d_op = &affs_dentry_operations; sb->s_root = d_make_root(root_inode); if (!sb->s_root) { pr_err("AFFS: Get root inode failed\n"); return -ENOMEM; } sb->s_export_op = &affs_export_ops; pr_debug("s_flags=%lX\n", sb->s_flags); return 0; } static int affs_reconfigure(struct fs_context *fc) { struct super_block *sb = fc->root->d_sb; struct affs_context *ctx = fc->fs_private; struct affs_sb_info *sbi = AFFS_SB(sb); int res = 0; sync_filesystem(sb); fc->sb_flags |= SB_NODIRATIME; flush_delayed_work(&sbi->sb_work); /* * NB: Historically, only mount_flags, mode, uid, gic, prefix, * and volume are accepted during remount. */ sbi->s_flags = ctx->mount_flags; sbi->s_mode = ctx->mode; sbi->s_uid = ctx->uid; sbi->s_gid = ctx->gid; /* protect against readers */ spin_lock(&sbi->symlink_lock); if (ctx->prefix) { kfree(sbi->s_prefix); sbi->s_prefix = ctx->prefix; ctx->prefix = NULL; } memcpy(sbi->s_volume, ctx->volume, 32); spin_unlock(&sbi->symlink_lock); if ((bool)(fc->sb_flags & SB_RDONLY) == sb_rdonly(sb)) return 0; if (fc->sb_flags & SB_RDONLY) affs_free_bitmap(sb); else res = affs_init_bitmap(sb, &fc->sb_flags); return res; } static int affs_statfs(struct dentry *dentry, struct kstatfs *buf) { struct super_block *sb = dentry->d_sb; int free; u64 id = huge_encode_dev(sb->s_bdev->bd_dev); pr_debug("%s() partsize=%d, reserved=%d\n", __func__, AFFS_SB(sb)->s_partition_size, AFFS_SB(sb)->s_reserved); free = affs_count_free_blocks(sb); buf->f_type = AFFS_SUPER_MAGIC; buf->f_bsize = sb->s_blocksize; buf->f_blocks = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved; buf->f_bfree = free; buf->f_bavail = free; buf->f_fsid = u64_to_fsid(id); buf->f_namelen = AFFSNAMEMAX; return 0; } static int affs_get_tree(struct fs_context *fc) { return get_tree_bdev(fc, affs_fill_super); } static void affs_kill_sb(struct super_block *sb) { struct affs_sb_info *sbi = AFFS_SB(sb); kill_block_super(sb); if (sbi) { affs_free_bitmap(sb); affs_brelse(sbi->s_root_bh); kfree(sbi->s_prefix); mutex_destroy(&sbi->s_bmlock); kfree_rcu(sbi, rcu); } } static void affs_free_fc(struct fs_context *fc) { struct affs_context *ctx = fc->fs_private; kfree(ctx->prefix); kfree(ctx); } static const struct fs_context_operations affs_context_ops = { .parse_param = affs_parse_param, .get_tree = affs_get_tree, .reconfigure = affs_reconfigure, .free = affs_free_fc, }; static int affs_init_fs_context(struct fs_context *fc) { struct affs_context *ctx; ctx = kzalloc(sizeof(struct affs_context), GFP_KERNEL); if (!ctx) return -ENOMEM; if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) { struct super_block *sb = fc->root->d_sb; struct affs_sb_info *sbi = AFFS_SB(sb); /* * NB: historically, no options other than volume were * preserved across a remount unless they were explicitly * passed in. */ memcpy(ctx->volume, sbi->s_volume, 32); } else { ctx->uid = current_uid(); ctx->gid = current_gid(); ctx->reserved = 2; ctx->root_block = -1; ctx->blocksize = -1; ctx->volume[0] = ':'; } fc->ops = &affs_context_ops; fc->fs_private = ctx; return 0; } static struct file_system_type affs_fs_type = { .owner = THIS_MODULE, .name = "affs", .kill_sb = affs_kill_sb, .fs_flags = FS_REQUIRES_DEV, .init_fs_context = affs_init_fs_context, .parameters = affs_param_spec, }; MODULE_ALIAS_FS("affs"); static int __init init_affs_fs(void) { int err = init_inodecache(); if (err) goto out1; err = register_filesystem(&affs_fs_type); if (err) goto out; return 0; out: destroy_inodecache(); out1: return err; } static void __exit exit_affs_fs(void) { unregister_filesystem(&affs_fs_type); destroy_inodecache(); } MODULE_DESCRIPTION("Amiga filesystem support for Linux"); MODULE_LICENSE("GPL"); module_init(init_affs_fs) module_exit(exit_affs_fs)