/* * linux/fs/adfs/super.c * * Copyright (C) 1997-1999 Russell King * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include <linux/module.h> #include <linux/init.h> #include <linux/buffer_head.h> #include <linux/parser.h> #include <linux/mount.h> #include <linux/seq_file.h> #include <linux/slab.h> #include <linux/statfs.h> #include "adfs.h" #include "dir_f.h" #include "dir_fplus.h" #define ADFS_DEFAULT_OWNER_MASK S_IRWXU #define ADFS_DEFAULT_OTHER_MASK (S_IRWXG | S_IRWXO) void __adfs_error(struct super_block *sb, const char *function, const char *fmt, ...) { char error_buf[128]; va_list args; va_start(args, fmt); vsnprintf(error_buf, sizeof(error_buf), fmt, args); va_end(args); printk(KERN_CRIT "ADFS-fs error (device %s)%s%s: %s\n", sb->s_id, function ? ": " : "", function ? function : "", error_buf); } static int adfs_checkdiscrecord(struct adfs_discrecord *dr) { int i; /* sector size must be 256, 512 or 1024 bytes */ if (dr->log2secsize != 8 && dr->log2secsize != 9 && dr->log2secsize != 10) return 1; /* idlen must be at least log2secsize + 3 */ if (dr->idlen < dr->log2secsize + 3) return 1; /* we cannot have such a large disc that we * are unable to represent sector offsets in * 32 bits. This works out at 2.0 TB. */ if (le32_to_cpu(dr->disc_size_high) >> dr->log2secsize) return 1; /* idlen must be no greater than 19 v2 [1.0] */ if (dr->idlen > 19) return 1; /* reserved bytes should be zero */ for (i = 0; i < sizeof(dr->unused52); i++) if (dr->unused52[i] != 0) return 1; return 0; } static unsigned char adfs_calczonecheck(struct super_block *sb, unsigned char *map) { unsigned int v0, v1, v2, v3; int i; v0 = v1 = v2 = v3 = 0; for (i = sb->s_blocksize - 4; i; i -= 4) { v0 += map[i] + (v3 >> 8); v3 &= 0xff; v1 += map[i + 1] + (v0 >> 8); v0 &= 0xff; v2 += map[i + 2] + (v1 >> 8); v1 &= 0xff; v3 += map[i + 3] + (v2 >> 8); v2 &= 0xff; } v0 += v3 >> 8; v1 += map[1] + (v0 >> 8); v2 += map[2] + (v1 >> 8); v3 += map[3] + (v2 >> 8); return v0 ^ v1 ^ v2 ^ v3; } static int adfs_checkmap(struct super_block *sb, struct adfs_discmap *dm) { unsigned char crosscheck = 0, zonecheck = 1; int i; for (i = 0; i < ADFS_SB(sb)->s_map_size; i++) { unsigned char *map; map = dm[i].dm_bh->b_data; if (adfs_calczonecheck(sb, map) != map[0]) { adfs_error(sb, "zone %d fails zonecheck", i); zonecheck = 0; } crosscheck ^= map[3]; } if (crosscheck != 0xff) adfs_error(sb, "crosscheck != 0xff"); return crosscheck == 0xff && zonecheck; } static void adfs_put_super(struct super_block *sb) { int i; struct adfs_sb_info *asb = ADFS_SB(sb); for (i = 0; i < asb->s_map_size; i++) brelse(asb->s_map[i].dm_bh); kfree(asb->s_map); kfree(asb); sb->s_fs_info = NULL; } static int adfs_show_options(struct seq_file *seq, struct dentry *root) { struct adfs_sb_info *asb = ADFS_SB(root->d_sb); if (asb->s_uid != 0) seq_printf(seq, ",uid=%u", asb->s_uid); if (asb->s_gid != 0) seq_printf(seq, ",gid=%u", asb->s_gid); if (asb->s_owner_mask != ADFS_DEFAULT_OWNER_MASK) seq_printf(seq, ",ownmask=%o", asb->s_owner_mask); if (asb->s_other_mask != ADFS_DEFAULT_OTHER_MASK) seq_printf(seq, ",othmask=%o", asb->s_other_mask); if (asb->s_ftsuffix != 0) seq_printf(seq, ",ftsuffix=%u", asb->s_ftsuffix); return 0; } enum {Opt_uid, Opt_gid, Opt_ownmask, Opt_othmask, Opt_ftsuffix, Opt_err}; static const match_table_t tokens = { {Opt_uid, "uid=%u"}, {Opt_gid, "gid=%u"}, {Opt_ownmask, "ownmask=%o"}, {Opt_othmask, "othmask=%o"}, {Opt_ftsuffix, "ftsuffix=%u"}, {Opt_err, NULL} }; static int parse_options(struct super_block *sb, char *options) { char *p; struct adfs_sb_info *asb = ADFS_SB(sb); int option; if (!options) return 0; while ((p = strsep(&options, ",")) != NULL) { substring_t args[MAX_OPT_ARGS]; int token; if (!*p) continue; token = match_token(p, tokens, args); switch (token) { case Opt_uid: if (match_int(args, &option)) return -EINVAL; asb->s_uid = option; break; case Opt_gid: if (match_int(args, &option)) return -EINVAL; asb->s_gid = option; break; case Opt_ownmask: if (match_octal(args, &option)) return -EINVAL; asb->s_owner_mask = option; break; case Opt_othmask: if (match_octal(args, &option)) return -EINVAL; asb->s_other_mask = option; break; case Opt_ftsuffix: if (match_int(args, &option)) return -EINVAL; asb->s_ftsuffix = option; break; default: printk("ADFS-fs: unrecognised mount option \"%s\" " "or missing value\n", p); return -EINVAL; } } return 0; } static int adfs_remount(struct super_block *sb, int *flags, char *data) { *flags |= MS_NODIRATIME; return parse_options(sb, data); } static int adfs_statfs(struct dentry *dentry, struct kstatfs *buf) { struct super_block *sb = dentry->d_sb; struct adfs_sb_info *sbi = ADFS_SB(sb); u64 id = huge_encode_dev(sb->s_bdev->bd_dev); buf->f_type = ADFS_SUPER_MAGIC; buf->f_namelen = sbi->s_namelen; buf->f_bsize = sb->s_blocksize; buf->f_blocks = sbi->s_size; buf->f_files = sbi->s_ids_per_zone * sbi->s_map_size; buf->f_bavail = buf->f_bfree = adfs_map_free(sb); buf->f_ffree = (long)(buf->f_bfree * buf->f_files) / (long)buf->f_blocks; buf->f_fsid.val[0] = (u32)id; buf->f_fsid.val[1] = (u32)(id >> 32); return 0; } static struct kmem_cache *adfs_inode_cachep; static struct inode *adfs_alloc_inode(struct super_block *sb) { struct adfs_inode_info *ei; ei = (struct adfs_inode_info *)kmem_cache_alloc(adfs_inode_cachep, GFP_KERNEL); if (!ei) return NULL; return &ei->vfs_inode; } static void adfs_i_callback(struct rcu_head *head) { struct inode *inode = container_of(head, struct inode, i_rcu); INIT_LIST_HEAD(&inode->i_dentry); kmem_cache_free(adfs_inode_cachep, ADFS_I(inode)); } static void adfs_destroy_inode(struct inode *inode) { call_rcu(&inode->i_rcu, adfs_i_callback); } static void init_once(void *foo) { struct adfs_inode_info *ei = (struct adfs_inode_info *) foo; inode_init_once(&ei->vfs_inode); } static int init_inodecache(void) { adfs_inode_cachep = kmem_cache_create("adfs_inode_cache", sizeof(struct adfs_inode_info), 0, (SLAB_RECLAIM_ACCOUNT| SLAB_MEM_SPREAD), init_once); if (adfs_inode_cachep == NULL) return -ENOMEM; return 0; } static void destroy_inodecache(void) { kmem_cache_destroy(adfs_inode_cachep); } static const struct super_operations adfs_sops = { .alloc_inode = adfs_alloc_inode, .destroy_inode = adfs_destroy_inode, .write_inode = adfs_write_inode, .put_super = adfs_put_super, .statfs = adfs_statfs, .remount_fs = adfs_remount, .show_options = adfs_show_options, }; static struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr) { struct adfs_discmap *dm; unsigned int map_addr, zone_size, nzones; int i, zone; struct adfs_sb_info *asb = ADFS_SB(sb); nzones = asb->s_map_size; zone_size = (8 << dr->log2secsize) - le16_to_cpu(dr->zone_spare); map_addr = (nzones >> 1) * zone_size - ((nzones > 1) ? ADFS_DR_SIZE_BITS : 0); map_addr = signed_asl(map_addr, asb->s_map2blk); asb->s_ids_per_zone = zone_size / (asb->s_idlen + 1); dm = kmalloc(nzones * sizeof(*dm), GFP_KERNEL); if (dm == NULL) { adfs_error(sb, "not enough memory"); return NULL; } for (zone = 0; zone < nzones; zone++, map_addr++) { dm[zone].dm_startbit = 0; dm[zone].dm_endbit = zone_size; dm[zone].dm_startblk = zone * zone_size - ADFS_DR_SIZE_BITS; dm[zone].dm_bh = sb_bread(sb, map_addr); if (!dm[zone].dm_bh) { adfs_error(sb, "unable to read map"); goto error_free; } } /* adjust the limits for the first and last map zones */ i = zone - 1; dm[0].dm_startblk = 0; dm[0].dm_startbit = ADFS_DR_SIZE_BITS; dm[i].dm_endbit = (le32_to_cpu(dr->disc_size_high) << (32 - dr->log2bpmb)) + (le32_to_cpu(dr->disc_size) >> dr->log2bpmb) + (ADFS_DR_SIZE_BITS - i * zone_size); if (adfs_checkmap(sb, dm)) return dm; adfs_error(sb, "map corrupted"); error_free: while (--zone >= 0) brelse(dm[zone].dm_bh); kfree(dm); return NULL; } static inline unsigned long adfs_discsize(struct adfs_discrecord *dr, int block_bits) { unsigned long discsize; discsize = le32_to_cpu(dr->disc_size_high) << (32 - block_bits); discsize |= le32_to_cpu(dr->disc_size) >> block_bits; return discsize; } static int adfs_fill_super(struct super_block *sb, void *data, int silent) { struct adfs_discrecord *dr; struct buffer_head *bh; struct object_info root_obj; unsigned char *b_data; struct adfs_sb_info *asb; struct inode *root; sb->s_flags |= MS_NODIRATIME; asb = kzalloc(sizeof(*asb), GFP_KERNEL); if (!asb) return -ENOMEM; sb->s_fs_info = asb; /* set default options */ asb->s_uid = 0; asb->s_gid = 0; asb->s_owner_mask = ADFS_DEFAULT_OWNER_MASK; asb->s_other_mask = ADFS_DEFAULT_OTHER_MASK; asb->s_ftsuffix = 0; if (parse_options(sb, data)) goto error; sb_set_blocksize(sb, BLOCK_SIZE); if (!(bh = sb_bread(sb, ADFS_DISCRECORD / BLOCK_SIZE))) { adfs_error(sb, "unable to read superblock"); goto error; } b_data = bh->b_data + (ADFS_DISCRECORD % BLOCK_SIZE); if (adfs_checkbblk(b_data)) { if (!silent) printk("VFS: Can't find an adfs filesystem on dev " "%s.\n", sb->s_id); goto error_free_bh; } dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET); /* * Do some sanity checks on the ADFS disc record */ if (adfs_checkdiscrecord(dr)) { if (!silent) printk("VPS: Can't find an adfs filesystem on dev " "%s.\n", sb->s_id); goto error_free_bh; } brelse(bh); if (sb_set_blocksize(sb, 1 << dr->log2secsize)) { bh = sb_bread(sb, ADFS_DISCRECORD / sb->s_blocksize); if (!bh) { adfs_error(sb, "couldn't read superblock on " "2nd try."); goto error; } b_data = bh->b_data + (ADFS_DISCRECORD % sb->s_blocksize); if (adfs_checkbblk(b_data)) { adfs_error(sb, "disc record mismatch, very weird!"); goto error_free_bh; } dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET); } else { if (!silent) printk(KERN_ERR "VFS: Unsupported blocksize on dev " "%s.\n", sb->s_id); goto error; } /* * blocksize on this device should now be set to the ADFS log2secsize */ sb->s_magic = ADFS_SUPER_MAGIC; asb->s_idlen = dr->idlen; asb->s_map_size = dr->nzones | (dr->nzones_high << 8); asb->s_map2blk = dr->log2bpmb - dr->log2secsize; asb->s_size = adfs_discsize(dr, sb->s_blocksize_bits); asb->s_version = dr->format_version; asb->s_log2sharesize = dr->log2sharesize; asb->s_map = adfs_read_map(sb, dr); if (!asb->s_map) goto error_free_bh; brelse(bh); /* * set up enough so that we can read an inode */ sb->s_op = &adfs_sops; dr = (struct adfs_discrecord *)(asb->s_map[0].dm_bh->b_data + 4); root_obj.parent_id = root_obj.file_id = le32_to_cpu(dr->root); root_obj.name_len = 0; /* Set root object date as 01 Jan 1987 00:00:00 */ root_obj.loadaddr = 0xfff0003f; root_obj.execaddr = 0xec22c000; root_obj.size = ADFS_NEWDIR_SIZE; root_obj.attr = ADFS_NDA_DIRECTORY | ADFS_NDA_OWNER_READ | ADFS_NDA_OWNER_WRITE | ADFS_NDA_PUBLIC_READ; root_obj.filetype = -1; /* * If this is a F+ disk with variable length directories, * get the root_size from the disc record. */ if (asb->s_version) { root_obj.size = le32_to_cpu(dr->root_size); asb->s_dir = &adfs_fplus_dir_ops; asb->s_namelen = ADFS_FPLUS_NAME_LEN; } else { asb->s_dir = &adfs_f_dir_ops; asb->s_namelen = ADFS_F_NAME_LEN; } /* * ,xyz hex filetype suffix may be added by driver * to files that have valid RISC OS filetype */ if (asb->s_ftsuffix) asb->s_namelen += 4; sb->s_d_op = &adfs_dentry_operations; root = adfs_iget(sb, &root_obj); sb->s_root = d_make_root(root); if (!sb->s_root) { int i; for (i = 0; i < asb->s_map_size; i++) brelse(asb->s_map[i].dm_bh); kfree(asb->s_map); adfs_error(sb, "get root inode failed\n"); goto error; } return 0; error_free_bh: brelse(bh); error: sb->s_fs_info = NULL; kfree(asb); return -EINVAL; } static struct dentry *adfs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) { return mount_bdev(fs_type, flags, dev_name, data, adfs_fill_super); } static struct file_system_type adfs_fs_type = { .owner = THIS_MODULE, .name = "adfs", .mount = adfs_mount, .kill_sb = kill_block_super, .fs_flags = FS_REQUIRES_DEV, }; static int __init init_adfs_fs(void) { int err = init_inodecache(); if (err) goto out1; err = register_filesystem(&adfs_fs_type); if (err) goto out; return 0; out: destroy_inodecache(); out1: return err; } static void __exit exit_adfs_fs(void) { unregister_filesystem(&adfs_fs_type); destroy_inodecache(); } module_init(init_adfs_fs) module_exit(exit_adfs_fs) MODULE_LICENSE("GPL");