[people/ms/linux.git] / fs / adfs / super.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  linux/fs/adfs/super.c
 *
 *  Copyright (C) 1997-1999 Russell King
 */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/parser.h>
#include <linux/mount.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/statfs.h>
#include <linux/user_namespace.h>
#include <linux/blkdev.h>
#include "adfs.h"
#include "dir_f.h"
#include "dir_fplus.h"

#define ADFS_SB_FLAGS SB_NOATIME

#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, ...)
{
	struct va_format vaf;
	va_list args;

	va_start(args, fmt);
	vaf.fmt = fmt;
	vaf.va = &args;

	printk(KERN_CRIT "ADFS-fs error (device %s)%s%s: %pV\n",
		sb->s_id, function ? ": " : "",
		function ? function : "", &vaf);

	va_end(args);
}

void adfs_msg(struct super_block *sb, const char *pfx, const char *fmt, ...)
{
	struct va_format vaf;
	va_list args;

	va_start(args, fmt);
	vaf.fmt = fmt;
	vaf.va = &args;
	printk("%sADFS-fs (%s): %pV\n", pfx, sb->s_id, &vaf);
	va_end(args);
}

static int adfs_checkdiscrecord(struct adfs_discrecord *dr)
{
	unsigned int max_idlen;
	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;

	/*
	 * Maximum idlen is limited to 16 bits for new directories by
	 * the three-byte storage of an indirect disc address.  For
	 * big directories, idlen must be no greater than 19 v2 [1.0]
	 */
	max_idlen = dr->format_version ? 19 : 16;
	if (dr->idlen > max_idlen)
		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 void adfs_put_super(struct super_block *sb)
{
	struct adfs_sb_info *asb = ADFS_SB(sb);

	adfs_free_map(sb);
	kfree_rcu(asb, rcu);
}

static int adfs_show_options(struct seq_file *seq, struct dentry *root)
{
	struct adfs_sb_info *asb = ADFS_SB(root->d_sb);

	if (!uid_eq(asb->s_uid, GLOBAL_ROOT_UID))
		seq_printf(seq, ",uid=%u", from_kuid_munged(&init_user_ns, asb->s_uid));
	if (!gid_eq(asb->s_gid, GLOBAL_ROOT_GID))
		seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, 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, struct adfs_sb_info *asb,
			 char *options)
{
	char *p;
	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 = make_kuid(current_user_ns(), option);
			if (!uid_valid(asb->s_uid))
				return -EINVAL;
			break;
		case Opt_gid:
			if (match_int(args, &option))
				return -EINVAL;
			asb->s_gid = make_kgid(current_user_ns(), option);
			if (!gid_valid(asb->s_gid))
				return -EINVAL;
			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:
			adfs_msg(sb, KERN_ERR,
				 "unrecognised mount option \"%s\" or missing value",
				 p);
			return -EINVAL;
		}
	}
	return 0;
}

static int adfs_remount(struct super_block *sb, int *flags, char *data)
{
	struct adfs_sb_info temp_asb;
	int ret;

	sync_filesystem(sb);
	*flags |= ADFS_SB_FLAGS;

	temp_asb = *ADFS_SB(sb);
	ret = parse_options(sb, &temp_asb, data);
	if (ret == 0)
		*ADFS_SB(sb) = temp_asb;

	return ret;
}

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);

	adfs_map_statfs(sb, buf);

	buf->f_type    = ADFS_SUPER_MAGIC;
	buf->f_namelen = sbi->s_namelen;
	buf->f_bsize   = sb->s_blocksize;
	buf->f_ffree   = (long)(buf->f_bfree * buf->f_files) / (long)buf->f_blocks;
	buf->f_fsid    = u64_to_fsid(id);

	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 = alloc_inode_sb(sb, adfs_inode_cachep, GFP_KERNEL);
	if (!ei)
		return NULL;
	return &ei->vfs_inode;
}

static void adfs_free_inode(struct inode *inode)
{
	kmem_cache_free(adfs_inode_cachep, ADFS_I(inode));
}

static int adfs_drop_inode(struct inode *inode)
{
	/* always drop inodes if we are read-only */
	return !IS_ENABLED(CONFIG_ADFS_FS_RW) || IS_RDONLY(inode);
}

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 init_inodecache(void)
{
	adfs_inode_cachep = kmem_cache_create("adfs_inode_cache",
					     sizeof(struct adfs_inode_info),
					     0, (SLAB_RECLAIM_ACCOUNT|
						SLAB_MEM_SPREAD|SLAB_ACCOUNT),
					     init_once);
	if (adfs_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(adfs_inode_cachep);
}

static const struct super_operations adfs_sops = {
	.alloc_inode	= adfs_alloc_inode,
	.free_inode	= adfs_free_inode,
	.drop_inode	= adfs_drop_inode,
	.write_inode	= adfs_write_inode,
	.put_super	= adfs_put_super,
	.statfs		= adfs_statfs,
	.remount_fs	= adfs_remount,
	.show_options	= adfs_show_options,
};

static int adfs_probe(struct super_block *sb, unsigned int offset, int silent,
		      int (*validate)(struct super_block *sb,
				      struct buffer_head *bh,
				      struct adfs_discrecord **bhp))
{
	struct adfs_sb_info *asb = ADFS_SB(sb);
	struct adfs_discrecord *dr;
	struct buffer_head *bh;
	unsigned int blocksize = BLOCK_SIZE;
	int ret, try;

	for (try = 0; try < 2; try++) {
		/* try to set the requested block size */
		if (sb->s_blocksize != blocksize &&
		    !sb_set_blocksize(sb, blocksize)) {
			if (!silent)
				adfs_msg(sb, KERN_ERR,
					 "error: unsupported blocksize");
			return -EINVAL;
		}

		/* read the buffer */
		bh = sb_bread(sb, offset >> sb->s_blocksize_bits);
		if (!bh) {
			adfs_msg(sb, KERN_ERR,
				 "error: unable to read block %u, try %d",
				 offset >> sb->s_blocksize_bits, try);
			return -EIO;
		}

		/* validate it */
		ret = validate(sb, bh, &dr);
		if (ret) {
			brelse(bh);
			return ret;
		}

		/* does the block size match the filesystem block size? */
		blocksize = 1 << dr->log2secsize;
		if (sb->s_blocksize == blocksize) {
			asb->s_map = adfs_read_map(sb, dr);
			brelse(bh);
			return PTR_ERR_OR_ZERO(asb->s_map);
		}

		brelse(bh);
	}

	return -EIO;
}

static int adfs_validate_bblk(struct super_block *sb, struct buffer_head *bh,
			      struct adfs_discrecord **drp)
{
	struct adfs_discrecord *dr;
	unsigned char *b_data;

	b_data = bh->b_data + (ADFS_DISCRECORD % sb->s_blocksize);
	if (adfs_checkbblk(b_data))
		return -EILSEQ;

	/* Do some sanity checks on the ADFS disc record */
	dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET);
	if (adfs_checkdiscrecord(dr))
		return -EILSEQ;

	*drp = dr;
	return 0;
}

static int adfs_validate_dr0(struct super_block *sb, struct buffer_head *bh,
			      struct adfs_discrecord **drp)
{
	struct adfs_discrecord *dr;

	/* Do some sanity checks on the ADFS disc record */
	dr = (struct adfs_discrecord *)(bh->b_data + 4);
	if (adfs_checkdiscrecord(dr) || dr->nzones_high || dr->nzones != 1)
		return -EILSEQ;

	*drp = dr;
	return 0;
}

static int adfs_fill_super(struct super_block *sb, void *data, int silent)
{
	struct adfs_discrecord *dr;
	struct object_info root_obj;
	struct adfs_sb_info *asb;
	struct inode *root;
	int ret = -EINVAL;

	sb->s_flags |= ADFS_SB_FLAGS;

	asb = kzalloc(sizeof(*asb), GFP_KERNEL);
	if (!asb)
		return -ENOMEM;

	sb->s_fs_info = asb;
	sb->s_magic = ADFS_SUPER_MAGIC;
	sb->s_time_gran = 10000000;

	/* set default options */
	asb->s_uid = GLOBAL_ROOT_UID;
	asb->s_gid = GLOBAL_ROOT_GID;
	asb->s_owner_mask = ADFS_DEFAULT_OWNER_MASK;
	asb->s_other_mask = ADFS_DEFAULT_OTHER_MASK;
	asb->s_ftsuffix = 0;

	if (parse_options(sb, asb, data))
		goto error;

	/* Try to probe the filesystem boot block */
	ret = adfs_probe(sb, ADFS_DISCRECORD, 1, adfs_validate_bblk);
	if (ret == -EILSEQ)
		ret = adfs_probe(sb, 0, silent, adfs_validate_dr0);
	if (ret == -EILSEQ) {
		if (!silent)
			adfs_msg(sb, KERN_ERR,
				 "error: can't find an ADFS filesystem on dev %s.",
				 sb->s_id);
		ret = -EINVAL;
	}
	if (ret)
		goto error;

	/* set up enough so that we can read an inode */
	sb->s_op = &adfs_sops;

	dr = adfs_map_discrecord(asb->s_map);

	root_obj.parent_id = root_obj.indaddr = 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;

	/*
	 * If this is a F+ disk with variable length directories,
	 * get the root_size from the disc record.
	 */
	if (dr->format_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) {
		adfs_free_map(sb);
		adfs_error(sb, "get root inode failed\n");
		ret = -EIO;
		goto error;
	}
	return 0;

error:
	sb->s_fs_info = NULL;
	kfree(asb);
	return ret;
}

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,
};
MODULE_ALIAS_FS("adfs");

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");
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
1da177e4 LT	2	/*
	3	* linux/fs/adfs/super.c
	4	*
	5	* Copyright (C) 1997-1999 Russell King
1da177e4 LT	6	*/
1da177e4 LT	7	#include <linux/module.h>
1da177e4	8	#include <linux/init.h>
1da177e4	9	#include <linux/parser.h>
e11400b0 MS	10	#include <linux/mount.h>
e11400b0 MS	11	#include <linux/seq_file.h>
5a0e3ad6	12	#include <linux/slab.h>
608ba50b	13	#include <linux/statfs.h>
c010d1ff	14	#include <linux/user_namespace.h>
621c1f42	15	#include <linux/blkdev.h>
1da177e4 LT	16	#include "adfs.h"
	17	#include "dir_f.h"
	18	#include "dir_fplus.h"
	19
421d3c0f RK	20	#define ADFS_SB_FLAGS SB_NOATIME
421d3c0f RK	21
e11400b0 MS	22	#define ADFS_DEFAULT_OWNER_MASK S_IRWXU
	23	#define ADFS_DEFAULT_OTHER_MASK (S_IRWXG \| S_IRWXO)
	24
1da177e4 LT	25	void __adfs_error(struct super_block sb, const char function, const char *fmt, ...)
1da177e4 LT	26	{
2e67080d	27	struct va_format vaf;
1da177e4 LT	28	va_list args;
	29
	30	va_start(args, fmt);
2e67080d RK	31	vaf.fmt = fmt;
2e67080d RK	32	vaf.va = &args;
1da177e4	33
2e67080d	34	printk(KERN_CRIT "ADFS-fs error (device %s)%s%s: %pV\n",
1da177e4	35	sb->s_id, function ? ": " : "",
2e67080d RK	36	function ? function : "", &vaf);
	37
	38	va_end(args);
1da177e4 LT	39	}
1da177e4 LT	40
ceb3b106 RK	41	void adfs_msg(struct super_block sb, const char pfx, const char *fmt, ...)
	42	{
	43	struct va_format vaf;
	44	va_list args;
	45
	46	va_start(args, fmt);
	47	vaf.fmt = fmt;
	48	vaf.va = &args;
	49	printk("%sADFS-fs (%s): %pV\n", pfx, sb->s_id, &vaf);
	50	va_end(args);
1da177e4 LT	51	}
	52
	53	static int adfs_checkdiscrecord(struct adfs_discrecord *dr)
	54	{
8616108d	55	unsigned int max_idlen;
1da177e4 LT	56	int i;
	57
	58	/* sector size must be 256, 512 or 1024 bytes */
	59	if (dr->log2secsize != 8 &&
	60	dr->log2secsize != 9 &&
	61	dr->log2secsize != 10)
	62	return 1;
	63
	64	/* idlen must be at least log2secsize + 3 */
	65	if (dr->idlen < dr->log2secsize + 3)
	66	return 1;
	67
	68	/* we cannot have such a large disc that we
	69	* are unable to represent sector offsets in
	70	* 32 bits. This works out at 2.0 TB.
	71	*/
	72	if (le32_to_cpu(dr->disc_size_high) >> dr->log2secsize)
	73	return 1;
	74
8616108d RK	75	/*
	76	* Maximum idlen is limited to 16 bits for new directories by
	77	* the three-byte storage of an indirect disc address. For
	78	* big directories, idlen must be no greater than 19 v2 [1.0]
	79	*/
	80	max_idlen = dr->format_version ? 19 : 16;
	81	if (dr->idlen > max_idlen)
1da177e4 LT	82	return 1;
	83
	84	/* reserved bytes should be zero */
	85	for (i = 0; i < sizeof(dr->unused52); i++)
	86	if (dr->unused52[i] != 0)
	87	return 1;
	88
	89	return 0;
	90	}
	91
1da177e4 LT	92	static void adfs_put_super(struct super_block *sb)
1da177e4 LT	93	{
1da177e4 LT	94	struct adfs_sb_info *asb = ADFS_SB(sb);
1da177e4 LT	95
7b195267	96	adfs_free_map(sb);
2d1d9b5b	97	kfree_rcu(asb, rcu);
1da177e4 LT	98	}
1da177e4 LT	99
34c80b1d	100	static int adfs_show_options(struct seq_file seq, struct dentry root)
e11400b0	101	{
34c80b1d	102	struct adfs_sb_info *asb = ADFS_SB(root->d_sb);
e11400b0	103
c010d1ff EB	104	if (!uid_eq(asb->s_uid, GLOBAL_ROOT_UID))
	105	seq_printf(seq, ",uid=%u", from_kuid_munged(&init_user_ns, asb->s_uid));
	106	if (!gid_eq(asb->s_gid, GLOBAL_ROOT_GID))
	107	seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, asb->s_gid));
e11400b0 MS	108	if (asb->s_owner_mask != ADFS_DEFAULT_OWNER_MASK)
	109	seq_printf(seq, ",ownmask=%o", asb->s_owner_mask);
	110	if (asb->s_other_mask != ADFS_DEFAULT_OTHER_MASK)
	111	seq_printf(seq, ",othmask=%o", asb->s_other_mask);
da23ef05 SS	112	if (asb->s_ftsuffix != 0)
da23ef05 SS	113	seq_printf(seq, ",ftsuffix=%u", asb->s_ftsuffix);
e11400b0 MS	114
	115	return 0;
	116	}
	117
da23ef05	118	enum {Opt_uid, Opt_gid, Opt_ownmask, Opt_othmask, Opt_ftsuffix, Opt_err};
1da177e4	119
a447c093	120	static const match_table_t tokens = {
1da177e4 LT	121	{Opt_uid, "uid=%u"},
	122	{Opt_gid, "gid=%u"},
	123	{Opt_ownmask, "ownmask=%o"},
	124	{Opt_othmask, "othmask=%o"},
da23ef05	125	{Opt_ftsuffix, "ftsuffix=%u"},
1da177e4 LT	126	{Opt_err, NULL}
	127	};
	128
4c5762f5 RK	129	static int parse_options(struct super_block sb, struct adfs_sb_info asb,
4c5762f5 RK	130	char *options)
1da177e4 LT	131	{
1da177e4 LT	132	char *p;
1da177e4 LT	133	int option;
	134
	135	if (!options)
	136	return 0;
	137
	138	while ((p = strsep(&options, ",")) != NULL) {
	139	substring_t args[MAX_OPT_ARGS];
	140	int token;
	141	if (!*p)
	142	continue;
	143
	144	token = match_token(p, tokens, args);
	145	switch (token) {
	146	case Opt_uid:
	147	if (match_int(args, &option))
	148	return -EINVAL;
c010d1ff EB	149	asb->s_uid = make_kuid(current_user_ns(), option);
	150	if (!uid_valid(asb->s_uid))
	151	return -EINVAL;
1da177e4 LT	152	break;
	153	case Opt_gid:
	154	if (match_int(args, &option))
	155	return -EINVAL;
c010d1ff EB	156	asb->s_gid = make_kgid(current_user_ns(), option);
	157	if (!gid_valid(asb->s_gid))
	158	return -EINVAL;
1da177e4 LT	159	break;
	160	case Opt_ownmask:
	161	if (match_octal(args, &option))
	162	return -EINVAL;
	163	asb->s_owner_mask = option;
	164	break;
	165	case Opt_othmask:
	166	if (match_octal(args, &option))
	167	return -EINVAL;
	168	asb->s_other_mask = option;
	169	break;
da23ef05 SS	170	case Opt_ftsuffix:
	171	if (match_int(args, &option))
	172	return -EINVAL;
	173	asb->s_ftsuffix = option;
	174	break;
1da177e4	175	default:
ceb3b106 RK	176	adfs_msg(sb, KERN_ERR,
	177	"unrecognised mount option \"%s\" or missing value",
	178	p);
1da177e4 LT	179	return -EINVAL;
	180	}
	181	}
	182	return 0;
	183	}
	184
	185	static int adfs_remount(struct super_block sb, int flags, char *data)
	186	{
4c5762f5 RK	187	struct adfs_sb_info temp_asb;
	188	int ret;
	189
02b9984d	190	sync_filesystem(sb);
421d3c0f	191	*flags \|= ADFS_SB_FLAGS;
4c5762f5 RK	192
	193	temp_asb = *ADFS_SB(sb);
	194	ret = parse_options(sb, &temp_asb, data);
	195	if (ret == 0)
	196	*ADFS_SB(sb) = temp_asb;
	197
	198	return ret;
1da177e4 LT	199	}
1da177e4 LT	200
726c3342	201	static int adfs_statfs(struct dentry dentry, struct kstatfs buf)
1da177e4	202	{
accb4012 CL	203	struct super_block *sb = dentry->d_sb;
	204	struct adfs_sb_info *sbi = ADFS_SB(sb);
	205	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
1da177e4	206
e6160e46 RK	207	adfs_map_statfs(sb, buf);
e6160e46 RK	208
1da177e4	209	buf->f_type = ADFS_SUPER_MAGIC;
accb4012 CL	210	buf->f_namelen = sbi->s_namelen;
accb4012 CL	211	buf->f_bsize = sb->s_blocksize;
1da177e4	212	buf->f_ffree = (long)(buf->f_bfree * buf->f_files) / (long)buf->f_blocks;
6d1349c7	213	buf->f_fsid = u64_to_fsid(id);
1da177e4 LT	214
	215	return 0;
	216	}
	217
e18b890b	218	static struct kmem_cache *adfs_inode_cachep;
1da177e4 LT	219
	220	static struct inode adfs_alloc_inode(struct super_block sb)
	221	{
	222	struct adfs_inode_info *ei;
fd60b288	223	ei = alloc_inode_sb(sb, adfs_inode_cachep, GFP_KERNEL);
1da177e4 LT	224	if (!ei)
	225	return NULL;
	226	return &ei->vfs_inode;
	227	}
	228
8f05a795	229	static void adfs_free_inode(struct inode *inode)
1da177e4 LT	230	{
	231	kmem_cache_free(adfs_inode_cachep, ADFS_I(inode));
	232	}
	233
f3520642 RK	234	static int adfs_drop_inode(struct inode *inode)
	235	{
	236	/* always drop inodes if we are read-only */
	237	return !IS_ENABLED(CONFIG_ADFS_FS_RW) \|\| IS_RDONLY(inode);
	238	}
	239
51cc5068	240	static void init_once(void *foo)
1da177e4 LT	241	{
	242	struct adfs_inode_info ei = (struct adfs_inode_info ) foo;
	243
a35afb83	244	inode_init_once(&ei->vfs_inode);
1da177e4	245	}
20c2df83	246
894122db	247	static int __init init_inodecache(void)
1da177e4 LT	248	{
	249	adfs_inode_cachep = kmem_cache_create("adfs_inode_cache",
	250	sizeof(struct adfs_inode_info),
fffb60f9	251	0, (SLAB_RECLAIM_ACCOUNT\|
5d097056	252	SLAB_MEM_SPREAD\|SLAB_ACCOUNT),
20c2df83	253	init_once);
1da177e4 LT	254	if (adfs_inode_cachep == NULL)
	255	return -ENOMEM;
	256	return 0;
	257	}
	258
	259	static void destroy_inodecache(void)
	260	{
8c0a8537 KS	261	/*
	262	* Make sure all delayed rcu free inodes are flushed before we
	263	* destroy cache.
	264	*/
	265	rcu_barrier();
1a1d92c1	266	kmem_cache_destroy(adfs_inode_cachep);
1da177e4 LT	267	}
1da177e4 LT	268
ee9b6d61	269	static const struct super_operations adfs_sops = {
1da177e4	270	.alloc_inode = adfs_alloc_inode,
8f05a795	271	.free_inode = adfs_free_inode,
f3520642	272	.drop_inode = adfs_drop_inode,
1da177e4 LT	273	.write_inode = adfs_write_inode,
	274	.put_super = adfs_put_super,
	275	.statfs = adfs_statfs,
	276	.remount_fs = adfs_remount,
e11400b0	277	.show_options = adfs_show_options,
1da177e4 LT	278	};
1da177e4 LT	279
e3858e12 RK	280	static int adfs_probe(struct super_block *sb, unsigned int offset, int silent,
	281	int (validate)(struct super_block sb,
	282	struct buffer_head *bh,
	283	struct adfs_discrecord **bhp))
1da177e4	284	{
e3858e12	285	struct adfs_sb_info *asb = ADFS_SB(sb);
1da177e4 LT	286	struct adfs_discrecord *dr;
1da177e4 LT	287	struct buffer_head *bh;
e3858e12 RK	288	unsigned int blocksize = BLOCK_SIZE;
	289	int ret, try;
	290
	291	for (try = 0; try < 2; try++) {
	292	/* try to set the requested block size */
	293	if (sb->s_blocksize != blocksize &&
	294	!sb_set_blocksize(sb, blocksize)) {
	295	if (!silent)
	296	adfs_msg(sb, KERN_ERR,
	297	"error: unsupported blocksize");
	298	return -EINVAL;
	299	}
	300
	301	/* read the buffer */
	302	bh = sb_bread(sb, offset >> sb->s_blocksize_bits);
	303	if (!bh) {
	304	adfs_msg(sb, KERN_ERR,
	305	"error: unable to read block %u, try %d",
	306	offset >> sb->s_blocksize_bits, try);
	307	return -EIO;
	308	}
	309
	310	/* validate it */
	311	ret = validate(sb, bh, &dr);
	312	if (ret) {
	313	brelse(bh);
	314	return ret;
	315	}
	316
	317	/* does the block size match the filesystem block size? */
	318	blocksize = 1 << dr->log2secsize;
	319	if (sb->s_blocksize == blocksize) {
	320	asb->s_map = adfs_read_map(sb, dr);
	321	brelse(bh);
	322	return PTR_ERR_OR_ZERO(asb->s_map);
	323	}
	324
	325	brelse(bh);
	326	}
	327
	328	return -EIO;
	329	}
	330
	331	static int adfs_validate_bblk(struct super_block sb, struct buffer_head bh,
	332	struct adfs_discrecord **drp)
	333	{
	334	struct adfs_discrecord *dr;
1da177e4	335	unsigned char *b_data;
e3858e12 RK	336
	337	b_data = bh->b_data + (ADFS_DISCRECORD % sb->s_blocksize);
	338	if (adfs_checkbblk(b_data))
	339	return -EILSEQ;
	340
	341	/* Do some sanity checks on the ADFS disc record */
	342	dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET);
	343	if (adfs_checkdiscrecord(dr))
	344	return -EILSEQ;
	345
	346	*drp = dr;
	347	return 0;
	348	}
	349
08ead1b8 RK	350	static int adfs_validate_dr0(struct super_block sb, struct buffer_head bh,
	351	struct adfs_discrecord **drp)
	352	{
	353	struct adfs_discrecord *dr;
	354
	355	/* Do some sanity checks on the ADFS disc record */
	356	dr = (struct adfs_discrecord *)(bh->b_data + 4);
	357	if (adfs_checkdiscrecord(dr) \|\| dr->nzones_high \|\| dr->nzones != 1)
	358	return -EILSEQ;
	359
	360	*drp = dr;
	361	return 0;
	362	}
	363
e3858e12 RK	364	static int adfs_fill_super(struct super_block sb, void data, int silent)
	365	{
	366	struct adfs_discrecord *dr;
	367	struct object_info root_obj;
1da177e4 LT	368	struct adfs_sb_info *asb;
1da177e4 LT	369	struct inode *root;
b7964106	370	int ret = -EINVAL;
1da177e4	371
421d3c0f	372	sb->s_flags \|= ADFS_SB_FLAGS;
1da177e4	373
f8314dc6	374	asb = kzalloc(sizeof(*asb), GFP_KERNEL);
4688a066	375	if (!asb)
1da177e4	376	return -ENOMEM;
eeeb9dd9	377
1da177e4	378	sb->s_fs_info = asb;
f6f14a0d	379	sb->s_magic = ADFS_SUPER_MAGIC;
eeeb9dd9	380	sb->s_time_gran = 10000000;
1da177e4 LT	381
1da177e4 LT	382	/* set default options */
c010d1ff EB	383	asb->s_uid = GLOBAL_ROOT_UID;
c010d1ff EB	384	asb->s_gid = GLOBAL_ROOT_GID;
e11400b0 MS	385	asb->s_owner_mask = ADFS_DEFAULT_OWNER_MASK;
e11400b0 MS	386	asb->s_other_mask = ADFS_DEFAULT_OTHER_MASK;
da23ef05	387	asb->s_ftsuffix = 0;
1da177e4	388
4c5762f5	389	if (parse_options(sb, asb, data))
1da177e4 LT	390	goto error;
1da177e4 LT	391
e3858e12	392	/* Try to probe the filesystem boot block */
08ead1b8 RK	393	ret = adfs_probe(sb, ADFS_DISCRECORD, 1, adfs_validate_bblk);
	394	if (ret == -EILSEQ)
	395	ret = adfs_probe(sb, 0, silent, adfs_validate_dr0);
e3858e12	396	if (ret == -EILSEQ) {
1da177e4	397	if (!silent)
ceb3b106	398	adfs_msg(sb, KERN_ERR,
e3858e12 RK	399	"error: can't find an ADFS filesystem on dev %s.",
e3858e12 RK	400	sb->s_id);
b7964106	401	ret = -EINVAL;
1da177e4	402	}
e3858e12 RK	403	if (ret)
e3858e12 RK	404	goto error;
1da177e4	405
e3858e12	406	/* set up enough so that we can read an inode */
1da177e4 LT	407	sb->s_op = &adfs_sops;
1da177e4 LT	408
1dfdfc94	409	dr = adfs_map_discrecord(asb->s_map);
1da177e4	410
5ed70bb4	411	root_obj.parent_id = root_obj.indaddr = le32_to_cpu(dr->root);
1da177e4	412	root_obj.name_len = 0;
da23ef05 SS	413	/* Set root object date as 01 Jan 1987 00:00:00 */
	414	root_obj.loadaddr = 0xfff0003f;
	415	root_obj.execaddr = 0xec22c000;
1da177e4 LT	416	root_obj.size = ADFS_NEWDIR_SIZE;
	417	root_obj.attr = ADFS_NDA_DIRECTORY \| ADFS_NDA_OWNER_READ \|
	418	ADFS_NDA_OWNER_WRITE \| ADFS_NDA_PUBLIC_READ;
	419
	420	/*
	421	* If this is a F+ disk with variable length directories,
	422	* get the root_size from the disc record.
	423	*/
cb88b5a3	424	if (dr->format_version) {
1da177e4 LT	425	root_obj.size = le32_to_cpu(dr->root_size);
	426	asb->s_dir = &adfs_fplus_dir_ops;
	427	asb->s_namelen = ADFS_FPLUS_NAME_LEN;
	428	} else {
	429	asb->s_dir = &adfs_f_dir_ops;
	430	asb->s_namelen = ADFS_F_NAME_LEN;
	431	}
da23ef05 SS	432	/*
	433	* ,xyz hex filetype suffix may be added by driver
	434	* to files that have valid RISC OS filetype
	435	*/
	436	if (asb->s_ftsuffix)
	437	asb->s_namelen += 4;
1da177e4	438
96e13914	439	sb->s_d_op = &adfs_dentry_operations;
1da177e4	440	root = adfs_iget(sb, &root_obj);
48fde701	441	sb->s_root = d_make_root(root);
1da177e4	442	if (!sb->s_root) {
7b195267	443	adfs_free_map(sb);
1da177e4	444	adfs_error(sb, "get root inode failed\n");
b7964106	445	ret = -EIO;
1da177e4	446	goto error;
96e13914	447	}
1da177e4 LT	448	return 0;
1da177e4 LT	449
1da177e4 LT	450	error:
	451	sb->s_fs_info = NULL;
	452	kfree(asb);
b7964106	453	return ret;
1da177e4 LT	454	}
1da177e4 LT	455
152a0836 AV	456	static struct dentry adfs_mount(struct file_system_type fs_type,
152a0836 AV	457	int flags, const char dev_name, void data)
1da177e4	458	{
152a0836	459	return mount_bdev(fs_type, flags, dev_name, data, adfs_fill_super);
1da177e4 LT	460	}
	461
	462	static struct file_system_type adfs_fs_type = {
	463	.owner = THIS_MODULE,
	464	.name = "adfs",
152a0836	465	.mount = adfs_mount,
1da177e4 LT	466	.kill_sb = kill_block_super,
	467	.fs_flags = FS_REQUIRES_DEV,
	468	};
7f78e035	469	MODULE_ALIAS_FS("adfs");
1da177e4 LT	470
	471	static int __init init_adfs_fs(void)
	472	{
	473	int err = init_inodecache();
	474	if (err)
	475	goto out1;
	476	err = register_filesystem(&adfs_fs_type);
	477	if (err)
	478	goto out;
	479	return 0;
	480	out:
	481	destroy_inodecache();
	482	out1:
	483	return err;
	484	}
	485
	486	static void __exit exit_adfs_fs(void)
	487	{
	488	unregister_filesystem(&adfs_fs_type);
	489	destroy_inodecache();
	490	}
	491
	492	module_init(init_adfs_fs)
	493	module_exit(exit_adfs_fs)
608ba50b	494	MODULE_LICENSE("GPL");