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494 lines
11 KiB
494 lines
11 KiB
// SPDX-License-Identifier: GPL-2.0-only |
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/* |
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* linux/fs/adfs/super.c |
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* |
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* Copyright (C) 1997-1999 Russell King |
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*/ |
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#include <linux/module.h> |
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#include <linux/init.h> |
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#include <linux/parser.h> |
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#include <linux/mount.h> |
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#include <linux/seq_file.h> |
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#include <linux/slab.h> |
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#include <linux/statfs.h> |
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#include <linux/user_namespace.h> |
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#include <linux/blkdev.h> |
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#include "adfs.h" |
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#include "dir_f.h" |
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#include "dir_fplus.h" |
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#define ADFS_SB_FLAGS SB_NOATIME |
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#define ADFS_DEFAULT_OWNER_MASK S_IRWXU |
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#define ADFS_DEFAULT_OTHER_MASK (S_IRWXG | S_IRWXO) |
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void __adfs_error(struct super_block *sb, const char *function, const char *fmt, ...) |
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{ |
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struct va_format vaf; |
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va_list args; |
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va_start(args, fmt); |
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vaf.fmt = fmt; |
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vaf.va = &args; |
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printk(KERN_CRIT "ADFS-fs error (device %s)%s%s: %pV\n", |
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sb->s_id, function ? ": " : "", |
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function ? function : "", &vaf); |
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va_end(args); |
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} |
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void adfs_msg(struct super_block *sb, const char *pfx, const char *fmt, ...) |
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{ |
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struct va_format vaf; |
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va_list args; |
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va_start(args, fmt); |
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vaf.fmt = fmt; |
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vaf.va = &args; |
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printk("%sADFS-fs (%s): %pV\n", pfx, sb->s_id, &vaf); |
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va_end(args); |
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} |
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static int adfs_checkdiscrecord(struct adfs_discrecord *dr) |
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{ |
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unsigned int max_idlen; |
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int i; |
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/* sector size must be 256, 512 or 1024 bytes */ |
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if (dr->log2secsize != 8 && |
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dr->log2secsize != 9 && |
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dr->log2secsize != 10) |
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return 1; |
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/* idlen must be at least log2secsize + 3 */ |
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if (dr->idlen < dr->log2secsize + 3) |
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return 1; |
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/* we cannot have such a large disc that we |
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* are unable to represent sector offsets in |
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* 32 bits. This works out at 2.0 TB. |
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*/ |
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if (le32_to_cpu(dr->disc_size_high) >> dr->log2secsize) |
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return 1; |
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/* |
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* Maximum idlen is limited to 16 bits for new directories by |
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* the three-byte storage of an indirect disc address. For |
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* big directories, idlen must be no greater than 19 v2 [1.0] |
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*/ |
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max_idlen = dr->format_version ? 19 : 16; |
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if (dr->idlen > max_idlen) |
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return 1; |
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/* reserved bytes should be zero */ |
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for (i = 0; i < sizeof(dr->unused52); i++) |
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if (dr->unused52[i] != 0) |
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return 1; |
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return 0; |
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} |
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static void adfs_put_super(struct super_block *sb) |
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{ |
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struct adfs_sb_info *asb = ADFS_SB(sb); |
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adfs_free_map(sb); |
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kfree_rcu(asb, rcu); |
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} |
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static int adfs_show_options(struct seq_file *seq, struct dentry *root) |
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{ |
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struct adfs_sb_info *asb = ADFS_SB(root->d_sb); |
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if (!uid_eq(asb->s_uid, GLOBAL_ROOT_UID)) |
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seq_printf(seq, ",uid=%u", from_kuid_munged(&init_user_ns, asb->s_uid)); |
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if (!gid_eq(asb->s_gid, GLOBAL_ROOT_GID)) |
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seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, asb->s_gid)); |
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if (asb->s_owner_mask != ADFS_DEFAULT_OWNER_MASK) |
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seq_printf(seq, ",ownmask=%o", asb->s_owner_mask); |
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if (asb->s_other_mask != ADFS_DEFAULT_OTHER_MASK) |
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seq_printf(seq, ",othmask=%o", asb->s_other_mask); |
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if (asb->s_ftsuffix != 0) |
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seq_printf(seq, ",ftsuffix=%u", asb->s_ftsuffix); |
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return 0; |
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} |
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enum {Opt_uid, Opt_gid, Opt_ownmask, Opt_othmask, Opt_ftsuffix, Opt_err}; |
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static const match_table_t tokens = { |
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{Opt_uid, "uid=%u"}, |
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{Opt_gid, "gid=%u"}, |
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{Opt_ownmask, "ownmask=%o"}, |
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{Opt_othmask, "othmask=%o"}, |
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{Opt_ftsuffix, "ftsuffix=%u"}, |
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{Opt_err, NULL} |
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}; |
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static int parse_options(struct super_block *sb, struct adfs_sb_info *asb, |
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char *options) |
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{ |
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char *p; |
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int option; |
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if (!options) |
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return 0; |
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while ((p = strsep(&options, ",")) != NULL) { |
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substring_t args[MAX_OPT_ARGS]; |
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int token; |
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if (!*p) |
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continue; |
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token = match_token(p, tokens, args); |
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switch (token) { |
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case Opt_uid: |
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if (match_int(args, &option)) |
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return -EINVAL; |
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asb->s_uid = make_kuid(current_user_ns(), option); |
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if (!uid_valid(asb->s_uid)) |
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return -EINVAL; |
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break; |
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case Opt_gid: |
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if (match_int(args, &option)) |
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return -EINVAL; |
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asb->s_gid = make_kgid(current_user_ns(), option); |
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if (!gid_valid(asb->s_gid)) |
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return -EINVAL; |
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break; |
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case Opt_ownmask: |
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if (match_octal(args, &option)) |
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return -EINVAL; |
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asb->s_owner_mask = option; |
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break; |
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case Opt_othmask: |
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if (match_octal(args, &option)) |
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return -EINVAL; |
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asb->s_other_mask = option; |
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break; |
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case Opt_ftsuffix: |
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if (match_int(args, &option)) |
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return -EINVAL; |
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asb->s_ftsuffix = option; |
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break; |
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default: |
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adfs_msg(sb, KERN_ERR, |
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"unrecognised mount option \"%s\" or missing value", |
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p); |
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return -EINVAL; |
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} |
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} |
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return 0; |
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} |
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static int adfs_remount(struct super_block *sb, int *flags, char *data) |
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{ |
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struct adfs_sb_info temp_asb; |
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int ret; |
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sync_filesystem(sb); |
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*flags |= ADFS_SB_FLAGS; |
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temp_asb = *ADFS_SB(sb); |
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ret = parse_options(sb, &temp_asb, data); |
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if (ret == 0) |
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*ADFS_SB(sb) = temp_asb; |
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return ret; |
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} |
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static int adfs_statfs(struct dentry *dentry, struct kstatfs *buf) |
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{ |
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struct super_block *sb = dentry->d_sb; |
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struct adfs_sb_info *sbi = ADFS_SB(sb); |
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u64 id = huge_encode_dev(sb->s_bdev->bd_dev); |
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adfs_map_statfs(sb, buf); |
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buf->f_type = ADFS_SUPER_MAGIC; |
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buf->f_namelen = sbi->s_namelen; |
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buf->f_bsize = sb->s_blocksize; |
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buf->f_ffree = (long)(buf->f_bfree * buf->f_files) / (long)buf->f_blocks; |
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buf->f_fsid = u64_to_fsid(id); |
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return 0; |
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} |
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static struct kmem_cache *adfs_inode_cachep; |
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static struct inode *adfs_alloc_inode(struct super_block *sb) |
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{ |
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struct adfs_inode_info *ei; |
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ei = kmem_cache_alloc(adfs_inode_cachep, GFP_KERNEL); |
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if (!ei) |
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return NULL; |
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return &ei->vfs_inode; |
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} |
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static void adfs_free_inode(struct inode *inode) |
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{ |
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kmem_cache_free(adfs_inode_cachep, ADFS_I(inode)); |
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} |
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static int adfs_drop_inode(struct inode *inode) |
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{ |
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/* always drop inodes if we are read-only */ |
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return !IS_ENABLED(CONFIG_ADFS_FS_RW) || IS_RDONLY(inode); |
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} |
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static void init_once(void *foo) |
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{ |
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struct adfs_inode_info *ei = (struct adfs_inode_info *) foo; |
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inode_init_once(&ei->vfs_inode); |
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} |
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static int __init init_inodecache(void) |
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{ |
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adfs_inode_cachep = kmem_cache_create("adfs_inode_cache", |
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sizeof(struct adfs_inode_info), |
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0, (SLAB_RECLAIM_ACCOUNT| |
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SLAB_MEM_SPREAD|SLAB_ACCOUNT), |
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init_once); |
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if (adfs_inode_cachep == NULL) |
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return -ENOMEM; |
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return 0; |
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} |
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static void destroy_inodecache(void) |
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{ |
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/* |
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* Make sure all delayed rcu free inodes are flushed before we |
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* destroy cache. |
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*/ |
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rcu_barrier(); |
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kmem_cache_destroy(adfs_inode_cachep); |
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} |
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static const struct super_operations adfs_sops = { |
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.alloc_inode = adfs_alloc_inode, |
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.free_inode = adfs_free_inode, |
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.drop_inode = adfs_drop_inode, |
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.write_inode = adfs_write_inode, |
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.put_super = adfs_put_super, |
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.statfs = adfs_statfs, |
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.remount_fs = adfs_remount, |
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.show_options = adfs_show_options, |
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}; |
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static int adfs_probe(struct super_block *sb, unsigned int offset, int silent, |
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int (*validate)(struct super_block *sb, |
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struct buffer_head *bh, |
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struct adfs_discrecord **bhp)) |
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{ |
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struct adfs_sb_info *asb = ADFS_SB(sb); |
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struct adfs_discrecord *dr; |
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struct buffer_head *bh; |
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unsigned int blocksize = BLOCK_SIZE; |
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int ret, try; |
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for (try = 0; try < 2; try++) { |
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/* try to set the requested block size */ |
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if (sb->s_blocksize != blocksize && |
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!sb_set_blocksize(sb, blocksize)) { |
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if (!silent) |
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adfs_msg(sb, KERN_ERR, |
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"error: unsupported blocksize"); |
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return -EINVAL; |
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} |
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/* read the buffer */ |
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bh = sb_bread(sb, offset >> sb->s_blocksize_bits); |
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if (!bh) { |
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adfs_msg(sb, KERN_ERR, |
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"error: unable to read block %u, try %d", |
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offset >> sb->s_blocksize_bits, try); |
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return -EIO; |
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} |
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/* validate it */ |
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ret = validate(sb, bh, &dr); |
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if (ret) { |
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brelse(bh); |
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return ret; |
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} |
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/* does the block size match the filesystem block size? */ |
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blocksize = 1 << dr->log2secsize; |
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if (sb->s_blocksize == blocksize) { |
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asb->s_map = adfs_read_map(sb, dr); |
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brelse(bh); |
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return PTR_ERR_OR_ZERO(asb->s_map); |
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} |
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brelse(bh); |
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} |
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return -EIO; |
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} |
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static int adfs_validate_bblk(struct super_block *sb, struct buffer_head *bh, |
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struct adfs_discrecord **drp) |
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{ |
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struct adfs_discrecord *dr; |
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unsigned char *b_data; |
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b_data = bh->b_data + (ADFS_DISCRECORD % sb->s_blocksize); |
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if (adfs_checkbblk(b_data)) |
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return -EILSEQ; |
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/* Do some sanity checks on the ADFS disc record */ |
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dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET); |
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if (adfs_checkdiscrecord(dr)) |
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return -EILSEQ; |
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*drp = dr; |
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return 0; |
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} |
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static int adfs_validate_dr0(struct super_block *sb, struct buffer_head *bh, |
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struct adfs_discrecord **drp) |
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{ |
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struct adfs_discrecord *dr; |
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/* Do some sanity checks on the ADFS disc record */ |
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dr = (struct adfs_discrecord *)(bh->b_data + 4); |
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if (adfs_checkdiscrecord(dr) || dr->nzones_high || dr->nzones != 1) |
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return -EILSEQ; |
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*drp = dr; |
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return 0; |
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} |
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static int adfs_fill_super(struct super_block *sb, void *data, int silent) |
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{ |
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struct adfs_discrecord *dr; |
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struct object_info root_obj; |
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struct adfs_sb_info *asb; |
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struct inode *root; |
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int ret = -EINVAL; |
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sb->s_flags |= ADFS_SB_FLAGS; |
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asb = kzalloc(sizeof(*asb), GFP_KERNEL); |
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if (!asb) |
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return -ENOMEM; |
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sb->s_fs_info = asb; |
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sb->s_magic = ADFS_SUPER_MAGIC; |
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sb->s_time_gran = 10000000; |
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/* set default options */ |
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asb->s_uid = GLOBAL_ROOT_UID; |
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asb->s_gid = GLOBAL_ROOT_GID; |
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asb->s_owner_mask = ADFS_DEFAULT_OWNER_MASK; |
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asb->s_other_mask = ADFS_DEFAULT_OTHER_MASK; |
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asb->s_ftsuffix = 0; |
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if (parse_options(sb, asb, data)) |
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goto error; |
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/* Try to probe the filesystem boot block */ |
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ret = adfs_probe(sb, ADFS_DISCRECORD, 1, adfs_validate_bblk); |
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if (ret == -EILSEQ) |
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ret = adfs_probe(sb, 0, silent, adfs_validate_dr0); |
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if (ret == -EILSEQ) { |
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if (!silent) |
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adfs_msg(sb, KERN_ERR, |
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"error: can't find an ADFS filesystem on dev %s.", |
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sb->s_id); |
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ret = -EINVAL; |
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} |
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if (ret) |
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goto error; |
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/* set up enough so that we can read an inode */ |
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sb->s_op = &adfs_sops; |
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dr = adfs_map_discrecord(asb->s_map); |
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root_obj.parent_id = root_obj.indaddr = le32_to_cpu(dr->root); |
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root_obj.name_len = 0; |
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/* Set root object date as 01 Jan 1987 00:00:00 */ |
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root_obj.loadaddr = 0xfff0003f; |
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root_obj.execaddr = 0xec22c000; |
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root_obj.size = ADFS_NEWDIR_SIZE; |
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root_obj.attr = ADFS_NDA_DIRECTORY | ADFS_NDA_OWNER_READ | |
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ADFS_NDA_OWNER_WRITE | ADFS_NDA_PUBLIC_READ; |
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/* |
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* If this is a F+ disk with variable length directories, |
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* get the root_size from the disc record. |
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*/ |
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if (dr->format_version) { |
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root_obj.size = le32_to_cpu(dr->root_size); |
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asb->s_dir = &adfs_fplus_dir_ops; |
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asb->s_namelen = ADFS_FPLUS_NAME_LEN; |
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} else { |
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asb->s_dir = &adfs_f_dir_ops; |
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asb->s_namelen = ADFS_F_NAME_LEN; |
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} |
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/* |
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* ,xyz hex filetype suffix may be added by driver |
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* to files that have valid RISC OS filetype |
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*/ |
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if (asb->s_ftsuffix) |
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asb->s_namelen += 4; |
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sb->s_d_op = &adfs_dentry_operations; |
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root = adfs_iget(sb, &root_obj); |
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sb->s_root = d_make_root(root); |
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if (!sb->s_root) { |
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adfs_free_map(sb); |
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adfs_error(sb, "get root inode failed\n"); |
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ret = -EIO; |
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goto error; |
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} |
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return 0; |
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error: |
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sb->s_fs_info = NULL; |
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kfree(asb); |
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return ret; |
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} |
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static struct dentry *adfs_mount(struct file_system_type *fs_type, |
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int flags, const char *dev_name, void *data) |
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{ |
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return mount_bdev(fs_type, flags, dev_name, data, adfs_fill_super); |
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} |
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static struct file_system_type adfs_fs_type = { |
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.owner = THIS_MODULE, |
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.name = "adfs", |
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.mount = adfs_mount, |
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.kill_sb = kill_block_super, |
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.fs_flags = FS_REQUIRES_DEV, |
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}; |
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MODULE_ALIAS_FS("adfs"); |
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static int __init init_adfs_fs(void) |
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{ |
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int err = init_inodecache(); |
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if (err) |
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goto out1; |
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err = register_filesystem(&adfs_fs_type); |
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if (err) |
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goto out; |
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return 0; |
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out: |
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destroy_inodecache(); |
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out1: |
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return err; |
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} |
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static void __exit exit_adfs_fs(void) |
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{ |
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unregister_filesystem(&adfs_fs_type); |
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destroy_inodecache(); |
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} |
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module_init(init_adfs_fs) |
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module_exit(exit_adfs_fs) |
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MODULE_LICENSE("GPL");
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