/* *  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/version.h>#include <linux/module.h>#include <linux/errno.h>#include <linux/fs.h>#include <linux/adfs_fs.h>#include <linux/slab.h>#include <linux/sched.h>#include <linux/stat.h>#include <linux/string.h>#include <linux/locks.h>#include <linux/init.h>#include <asm/bitops.h>#include <asm/uaccess.h>#include <asm/system.h>#include <stdarg.h>#include "adfs.h"#include "dir_f.h"#include "dir_fplus.h"void __adfs_error(struct super_block *sb, const char *function, const char *fmt, ...){	char error_buf[128];	va_list args;	va_start(args, fmt);	vsprintf(error_buf, fmt, args);	va_end(args);	printk(KERN_CRIT "ADFS-fs error (device %s)%s%s: %s\n",		bdevname(sb->s_dev), 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 (dr->disc_size_high >> dr->log2secsize)		return 1;	/*	 * The following checks are not required for F+	 * stage 1.	 */#if 0	/* idlen must be smaller be no greater than 15 */	if (dr->idlen > 15)		return 1;	/* nzones must be less than 128 for the root	 * directory to be addressable	 */	if (dr->nzones >= 128 && dr->nzones_high == 0)		return 1;	/* root must be of the form 0x2.. */	if ((le32_to_cpu(dr->root) & 0xffffff00) != 0x00000200)		return 1;#else	/*	 * Stage 2 F+ does not require the following check	 */#if 0	/* idlen must be no greater than 16 v2 [1.0] */	if (dr->idlen > 16)		return 1;	/* we can't handle F+ discs yet */	if (dr->format_version || dr->root_size)		return 1;#else	/* idlen must be no greater than 19 v2 [1.0] */	if (dr->idlen > 19)		return 1;#endif#endif	/* 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 < sb->u.adfs_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;	for (i = 0; i < sb->u.adfs_sb.s_map_size; i++)		brelse(sb->u.adfs_sb.s_map[i].dm_bh);	kfree(sb->u.adfs_sb.s_map);}static int parse_options(struct super_block *sb, char *options){	char *value, *opt;	if (!options)		return 0;	for (opt = strtok(options, ","); opt != NULL; opt = strtok(NULL, ",")) {		value = strchr(opt, '=');		if (value)			*value++ = '\0';		if (!strcmp(opt, "uid")) {	/* owner of all files */			if (!value || !*value)				return -EINVAL;			sb->u.adfs_sb.s_uid = simple_strtoul(value, &value, 0);			if (*value)				return -EINVAL;		} else		if (!strcmp(opt, "gid")) {	/* group owner of all files */			if (!value || !*value)				return -EINVAL;			sb->u.adfs_sb.s_gid = simple_strtoul(value, &value, 0);			if (*value)				return -EINVAL;		} else		if (!strcmp(opt, "ownmask")) {	/* owner permission mask */			if (!value || !*value)				return -EINVAL;			sb->u.adfs_sb.s_owner_mask = simple_strtoul(value, &value, 8);			if (*value)				return -EINVAL;		} else		if (!strcmp(opt, "othmask")) {	/* others permission mask */			if (!value || !*value)				return -EINVAL;			sb->u.adfs_sb.s_other_mask = simple_strtoul(value, &value, 8);			if (*value)				return -EINVAL;		} else {			/* eh? say again. */			printk("ADFS-fs: unrecognised mount option %s\n", opt);			return -EINVAL;		}	}	return 0;}static int adfs_remount(struct super_block *sb, int *flags, char *data){	return parse_options(sb, data);}static int adfs_statfs(struct super_block *sb, struct statfs *buf){	struct adfs_sb_info *asb = &sb->u.adfs_sb;	buf->f_type    = ADFS_SUPER_MAGIC;	buf->f_namelen = asb->s_namelen;	buf->f_bsize   = sb->s_blocksize;	buf->f_blocks  = asb->s_size;	buf->f_files   = asb->s_ids_per_zone * asb->s_map_size;	buf->f_bavail  =	buf->f_bfree   = adfs_map_free(sb);	buf->f_ffree   = buf->f_bfree * buf->f_files / buf->f_blocks;	return 0;}static struct super_operations adfs_sops = {	write_inode:	adfs_write_inode,	put_super:	adfs_put_super,	statfs:		adfs_statfs,	remount_fs:	adfs_remount,};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;	nzones    = sb->u.adfs_sb.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, sb->u.adfs_sb.s_map2blk);	sb->u.adfs_sb.s_ids_per_zone = zone_size / (sb->u.adfs_sb.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   = (dr->disc_size_high << (32 - dr->log2bpmb)) +			    (dr->disc_size >> dr->log2bpmb) +			    (ADFS_DR_SIZE_BITS - i * zone_size);	if (adfs_checkmap(sb, dm))		return dm;	adfs_error(sb, NULL, "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;}struct super_block *adfs_read_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;	kdev_t dev = sb->s_dev;	/* set default options */	sb->u.adfs_sb.s_uid = 0;	sb->u.adfs_sb.s_gid = 0;	sb->u.adfs_sb.s_owner_mask = S_IRWXU;	sb->u.adfs_sb.s_other_mask = S_IRWXG | S_IRWXO;	if (parse_options(sb, data))		goto error;	sb->s_blocksize = BLOCK_SIZE;	set_blocksize(dev, 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", bdevname(dev));		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", bdevname(dev));		goto error_free_bh;	}	sb->s_blocksize_bits = dr->log2secsize;	sb->s_blocksize = 1 << sb->s_blocksize_bits;	if (sb->s_blocksize != BLOCK_SIZE &&	    (sb->s_blocksize == 512 || sb->s_blocksize == 1024 ||	     sb->s_blocksize == 2048 || sb->s_blocksize == 4096)) {		brelse(bh);		set_blocksize(dev, sb->s_blocksize);		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);	}	if (sb->s_blocksize != bh->b_size) {		if (!silent)			printk(KERN_ERR "VFS: Unsupported blocksize on dev "				"%s.\n", bdevname(dev));		goto error_free_bh;	}	/*	 * blocksize on this device should now be set to the ADFS log2secsize	 */	sb->s_magic		 = ADFS_SUPER_MAGIC;	sb->u.adfs_sb.s_idlen	 = dr->idlen;	sb->u.adfs_sb.s_map_size = dr->nzones | (dr->nzones_high << 8);	sb->u.adfs_sb.s_map2blk	 = dr->log2bpmb - dr->log2secsize;	sb->u.adfs_sb.s_size     = adfs_discsize(dr, sb->s_blocksize_bits);	sb->u.adfs_sb.s_version  = dr->format_version;	sb->u.adfs_sb.s_log2sharesize = dr->log2sharesize;	printk(KERN_DEBUG "ADFS: idlen %d map bit size %d sector size %d\n",		dr->idlen, 1 << dr->log2bpmb, 1 << dr->log2secsize);	printk(KERN_DEBUG "ADFS: map size %d map2blk %d version %d share size %d\n",		sb->u.adfs_sb.s_map_size,		sb->u.adfs_sb.s_map2blk,		sb->u.adfs_sb.s_version,		1 << sb->u.adfs_sb.s_log2sharesize);		sb->u.adfs_sb.s_map = adfs_read_map(sb, dr);	if (!sb->u.adfs_sb.s_map)		goto error_free_bh;	brelse(bh);	printk(KERN_DEBUG "ADFS: ids per zone %d\n", sb->u.adfs_sb.s_ids_per_zone);	/*	 * set up enough so that we can read an inode	 */	sb->s_op = &adfs_sops;	dr = (struct adfs_discrecord *)(sb->u.adfs_sb.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;	root_obj.loadaddr  = 0;	root_obj.execaddr  = 0;	root_obj.size	   = ADFS_NEWDIR_SIZE;	root_obj.attr	   = ADFS_NDA_DIRECTORY   | ADFS_NDA_OWNER_READ |			     ADFS_NDA_OWNER_WRITE | ADFS_NDA_PUBLIC_READ;	/*	 * If this is a F+ disk with variable length directories,	 * get the root_size from the disc record.	 */	if (sb->u.adfs_sb.s_version) {		root_obj.size = dr->root_size;		sb->u.adfs_sb.s_dir     = &adfs_fplus_dir_ops;		sb->u.adfs_sb.s_namelen = ADFS_FPLUS_NAME_LEN;	} else {		sb->u.adfs_sb.s_dir     = &adfs_f_dir_ops;		sb->u.adfs_sb.s_namelen = ADFS_F_NAME_LEN;	}	sb->s_root = d_alloc_root(adfs_iget(sb, &root_obj));	if (!sb->s_root) {		int i;		for (i = 0; i < sb->u.adfs_sb.s_map_size; i++)			brelse(sb->u.adfs_sb.s_map[i].dm_bh);		kfree(sb->u.adfs_sb.s_map);		adfs_error(sb, "get root inode failed\n");		goto error;	} else		sb->s_root->d_op = &adfs_dentry_operations;	return sb;error_free_bh:	brelse(bh);error:	return NULL;}static DECLARE_FSTYPE_DEV(adfs_fs_type, "adfs", adfs_read_super);static int __init init_adfs_fs(void){	return register_filesystem(&adfs_fs_type);}static void __exit exit_adfs_fs(void){	unregister_filesystem(&adfs_fs_type);}EXPORT_NO_SYMBOLS;module_init(init_adfs_fs)module_exit(exit_adfs_fs)