[linux-block.git] / fs / affs / amigaffs.c

/*
 *  linux/fs/affs/amigaffs.c
 *
 *  (c) 1996  Hans-Joachim Widmaier - Rewritten
 *
 *  (C) 1993  Ray Burr - Amiga FFS filesystem.
 *
 *  Please send bug reports to: hjw@zvw.de
 */

#include "affs.h"

extern struct timezone sys_tz;

static char ErrorBuffer[256];

/*
 * Functions for accessing Amiga-FFS structures.
 */


/* Insert a header block bh into the directory dir
 * caller must hold AFFS_DIR->i_hash_lock!
 */

int
affs_insert_hash(struct inode *dir, struct buffer_head *bh)
{
	struct super_block *sb = dir->i_sb;
	struct buffer_head *dir_bh;
	u32 ino, hash_ino;
	int offset;

	ino = bh->b_blocknr;
	offset = affs_hash_name(sb, AFFS_TAIL(sb, bh)->name + 1, AFFS_TAIL(sb, bh)->name[0]);

	pr_debug("AFFS: insert_hash(dir=%u, ino=%d)\n", (u32)dir->i_ino, ino);

	dir_bh = affs_bread(sb, dir->i_ino);
	if (!dir_bh)
		return -EIO;

	hash_ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[offset]);
	while (hash_ino) {
		affs_brelse(dir_bh);
		dir_bh = affs_bread(sb, hash_ino);
		if (!dir_bh)
			return -EIO;
		hash_ino = be32_to_cpu(AFFS_TAIL(sb, dir_bh)->hash_chain);
	}
	AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
	AFFS_TAIL(sb, bh)->hash_chain = 0;
	affs_fix_checksum(sb, bh);

	if (dir->i_ino == dir_bh->b_blocknr)
		AFFS_HEAD(dir_bh)->table[offset] = cpu_to_be32(ino);
	else
		AFFS_TAIL(sb, dir_bh)->hash_chain = cpu_to_be32(ino);

	affs_adjust_checksum(dir_bh, ino);
	mark_buffer_dirty_inode(dir_bh, dir);
	affs_brelse(dir_bh);

	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
	dir->i_version++;
	mark_inode_dirty(dir);

	return 0;
}

/* Remove a header block from its directory.
 * caller must hold AFFS_DIR->i_hash_lock!
 */

int
affs_remove_hash(struct inode *dir, struct buffer_head *rem_bh)
{
	struct super_block *sb;
	struct buffer_head *bh;
	u32 rem_ino, hash_ino;
	__be32 ino;
	int offset, retval;

	sb = dir->i_sb;
	rem_ino = rem_bh->b_blocknr;
	offset = affs_hash_name(sb, AFFS_TAIL(sb, rem_bh)->name+1, AFFS_TAIL(sb, rem_bh)->name[0]);
	pr_debug("AFFS: remove_hash(dir=%d, ino=%d, hashval=%d)\n", (u32)dir->i_ino, rem_ino, offset);

	bh = affs_bread(sb, dir->i_ino);
	if (!bh)
		return -EIO;

	retval = -ENOENT;
	hash_ino = be32_to_cpu(AFFS_HEAD(bh)->table[offset]);
	while (hash_ino) {
		if (hash_ino == rem_ino) {
			ino = AFFS_TAIL(sb, rem_bh)->hash_chain;
			if (dir->i_ino == bh->b_blocknr)
				AFFS_HEAD(bh)->table[offset] = ino;
			else
				AFFS_TAIL(sb, bh)->hash_chain = ino;
			affs_adjust_checksum(bh, be32_to_cpu(ino) - hash_ino);
			mark_buffer_dirty_inode(bh, dir);
			AFFS_TAIL(sb, rem_bh)->parent = 0;
			retval = 0;
			break;
		}
		affs_brelse(bh);
		bh = affs_bread(sb, hash_ino);
		if (!bh)
			return -EIO;
		hash_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain);
	}

	affs_brelse(bh);

	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
	dir->i_version++;
	mark_inode_dirty(dir);

	return retval;
}

static void
affs_fix_dcache(struct inode *inode, u32 entry_ino)
{
	struct dentry *dentry;
	spin_lock(&inode->i_lock);
	hlist_for_each_entry(dentry, &inode->i_dentry, d_alias) {
		if (entry_ino == (u32)(long)dentry->d_fsdata) {
			dentry->d_fsdata = (void *)inode->i_ino;
			break;
		}
	}
	spin_unlock(&inode->i_lock);
}


/* Remove header from link chain */

static int
affs_remove_link(struct dentry *dentry)
{
	struct inode *dir, *inode = dentry->d_inode;
	struct super_block *sb = inode->i_sb;
	struct buffer_head *bh = NULL, *link_bh = NULL;
	u32 link_ino, ino;
	int retval;

	pr_debug("AFFS: remove_link(key=%ld)\n", inode->i_ino);
	retval = -EIO;
	bh = affs_bread(sb, inode->i_ino);
	if (!bh)
		goto done;

	link_ino = (u32)(long)dentry->d_fsdata;
	if (inode->i_ino == link_ino) {
		/* we can't remove the head of the link, as its blocknr is still used as ino,
		 * so we remove the block of the first link instead.
		 */ 
		link_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain);
		link_bh = affs_bread(sb, link_ino);
		if (!link_bh)
			goto done;

		dir = affs_iget(sb, be32_to_cpu(AFFS_TAIL(sb, link_bh)->parent));
		if (IS_ERR(dir)) {
			retval = PTR_ERR(dir);
			goto done;
		}

		affs_lock_dir(dir);
		/*
		 * if there's a dentry for that block, make it
		 * refer to inode itself.
		 */
		affs_fix_dcache(inode, link_ino);
		retval = affs_remove_hash(dir, link_bh);
		if (retval) {
			affs_unlock_dir(dir);
			goto done;
		}
		mark_buffer_dirty_inode(link_bh, inode);

		memcpy(AFFS_TAIL(sb, bh)->name, AFFS_TAIL(sb, link_bh)->name, 32);
		retval = affs_insert_hash(dir, bh);
		if (retval) {
			affs_unlock_dir(dir);
			goto done;
		}
		mark_buffer_dirty_inode(bh, inode);

		affs_unlock_dir(dir);
		iput(dir);
	} else {
		link_bh = affs_bread(sb, link_ino);
		if (!link_bh)
			goto done;
	}

	while ((ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain)) != 0) {
		if (ino == link_ino) {
			__be32 ino2 = AFFS_TAIL(sb, link_bh)->link_chain;
			AFFS_TAIL(sb, bh)->link_chain = ino2;
			affs_adjust_checksum(bh, be32_to_cpu(ino2) - link_ino);
			mark_buffer_dirty_inode(bh, inode);
			retval = 0;
			/* Fix the link count, if bh is a normal header block without links */
			switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
			case ST_LINKDIR:
			case ST_LINKFILE:
				break;
			default:
				if (!AFFS_TAIL(sb, bh)->link_chain)
					set_nlink(inode, 1);
			}
			affs_free_block(sb, link_ino);
			goto done;
		}
		affs_brelse(bh);
		bh = affs_bread(sb, ino);
		if (!bh)
			goto done;
	}
	retval = -ENOENT;
done:
	affs_brelse(link_bh);
	affs_brelse(bh);
	return retval;
}


static int
affs_empty_dir(struct inode *inode)
{
	struct super_block *sb = inode->i_sb;
	struct buffer_head *bh;
	int retval, size;

	retval = -EIO;
	bh = affs_bread(sb, inode->i_ino);
	if (!bh)
		goto done;

	retval = -ENOTEMPTY;
	for (size = AFFS_SB(sb)->s_hashsize - 1; size >= 0; size--)
		if (AFFS_HEAD(bh)->table[size])
			goto not_empty;
	retval = 0;
not_empty:
	affs_brelse(bh);
done:
	return retval;
}


/* Remove a filesystem object. If the object to be removed has
 * links to it, one of the links must be changed to inherit
 * the file or directory. As above, any inode will do.
 * The buffer will not be freed. If the header is a link, the
 * block will be marked as free.
 * This function returns a negative error number in case of
 * an error, else 0 if the inode is to be deleted or 1 if not.
 */

int
affs_remove_header(struct dentry *dentry)
{
	struct super_block *sb;
	struct inode *inode, *dir;
	struct buffer_head *bh = NULL;
	int retval;

	dir = dentry->d_parent->d_inode;
	sb = dir->i_sb;

	retval = -ENOENT;
	inode = dentry->d_inode;
	if (!inode)
		goto done;

	pr_debug("AFFS: remove_header(key=%ld)\n", inode->i_ino);
	retval = -EIO;
	bh = affs_bread(sb, (u32)(long)dentry->d_fsdata);
	if (!bh)
		goto done;

	affs_lock_link(inode);
	affs_lock_dir(dir);
	switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
	case ST_USERDIR:
		/* if we ever want to support links to dirs
		 * i_hash_lock of the inode must only be
		 * taken after some checks
		 */
		affs_lock_dir(inode);
		retval = affs_empty_dir(inode);
		affs_unlock_dir(inode);
		if (retval)
			goto done_unlock;
		break;
	default:
		break;
	}

	retval = affs_remove_hash(dir, bh);
	if (retval)
		goto done_unlock;
	mark_buffer_dirty_inode(bh, inode);

	affs_unlock_dir(dir);

	if (inode->i_nlink > 1)
		retval = affs_remove_link(dentry);
	else
		clear_nlink(inode);
	affs_unlock_link(inode);
	inode->i_ctime = CURRENT_TIME_SEC;
	mark_inode_dirty(inode);

done:
	affs_brelse(bh);
	return retval;

done_unlock:
	affs_unlock_dir(dir);
	affs_unlock_link(inode);
	goto done;
}

/* Checksum a block, do various consistency checks and optionally return
   the blocks type number.  DATA points to the block.  If their pointers
   are non-null, *PTYPE and *STYPE are set to the primary and secondary
   block types respectively, *HASHSIZE is set to the size of the hashtable
   (which lets us calculate the block size).
   Returns non-zero if the block is not consistent. */

u32
affs_checksum_block(struct super_block *sb, struct buffer_head *bh)
{
	__be32 *ptr = (__be32 *)bh->b_data;
	u32 sum;
	int bsize;

	sum = 0;
	for (bsize = sb->s_blocksize / sizeof(__be32); bsize > 0; bsize--)
		sum += be32_to_cpu(*ptr++);
	return sum;
}

/*
 * Calculate the checksum of a disk block and store it
 * at the indicated position.
 */

void
affs_fix_checksum(struct super_block *sb, struct buffer_head *bh)
{
	int cnt = sb->s_blocksize / sizeof(__be32);
	__be32 *ptr = (__be32 *)bh->b_data;
	u32 checksum;
	__be32 *checksumptr;

	checksumptr = ptr + 5;
	*checksumptr = 0;
	for (checksum = 0; cnt > 0; ptr++, cnt--)
		checksum += be32_to_cpu(*ptr);
	*checksumptr = cpu_to_be32(-checksum);
}

void
secs_to_datestamp(time_t secs, struct affs_date *ds)
{
	u32	 days;
	u32	 minute;

	secs -= sys_tz.tz_minuteswest * 60 + ((8 * 365 + 2) * 24 * 60 * 60);
	if (secs < 0)
		secs = 0;
	days    = secs / 86400;
	secs   -= days * 86400;
	minute  = secs / 60;
	secs   -= minute * 60;

	ds->days = cpu_to_be32(days);
	ds->mins = cpu_to_be32(minute);
	ds->ticks = cpu_to_be32(secs * 50);
}

umode_t
prot_to_mode(u32 prot)
{
	umode_t mode = 0;

	if (!(prot & FIBF_NOWRITE))
		mode |= S_IWUSR;
	if (!(prot & FIBF_NOREAD))
		mode |= S_IRUSR;
	if (!(prot & FIBF_NOEXECUTE))
		mode |= S_IXUSR;
	if (prot & FIBF_GRP_WRITE)
		mode |= S_IWGRP;
	if (prot & FIBF_GRP_READ)
		mode |= S_IRGRP;
	if (prot & FIBF_GRP_EXECUTE)
		mode |= S_IXGRP;
	if (prot & FIBF_OTR_WRITE)
		mode |= S_IWOTH;
	if (prot & FIBF_OTR_READ)
		mode |= S_IROTH;
	if (prot & FIBF_OTR_EXECUTE)
		mode |= S_IXOTH;

	return mode;
}

void
mode_to_prot(struct inode *inode)
{
	u32 prot = AFFS_I(inode)->i_protect;
	umode_t mode = inode->i_mode;

	if (!(mode & S_IXUSR))
		prot |= FIBF_NOEXECUTE;
	if (!(mode & S_IRUSR))
		prot |= FIBF_NOREAD;
	if (!(mode & S_IWUSR))
		prot |= FIBF_NOWRITE;
	if (mode & S_IXGRP)
		prot |= FIBF_GRP_EXECUTE;
	if (mode & S_IRGRP)
		prot |= FIBF_GRP_READ;
	if (mode & S_IWGRP)
		prot |= FIBF_GRP_WRITE;
	if (mode & S_IXOTH)
		prot |= FIBF_OTR_EXECUTE;
	if (mode & S_IROTH)
		prot |= FIBF_OTR_READ;
	if (mode & S_IWOTH)
		prot |= FIBF_OTR_WRITE;

	AFFS_I(inode)->i_protect = prot;
}

void
affs_error(struct super_block *sb, const char *function, const char *fmt, ...)
{
	va_list	 args;

	va_start(args,fmt);
	vsnprintf(ErrorBuffer,sizeof(ErrorBuffer),fmt,args);
	va_end(args);

	printk(KERN_CRIT "AFFS error (device %s): %s(): %s\n", sb->s_id,
		function,ErrorBuffer);
	if (!(sb->s_flags & MS_RDONLY))
		printk(KERN_WARNING "AFFS: Remounting filesystem read-only\n");
	sb->s_flags |= MS_RDONLY;
}

void
affs_warning(struct super_block *sb, const char *function, const char *fmt, ...)
{
	va_list	 args;

	va_start(args,fmt);
	vsnprintf(ErrorBuffer,sizeof(ErrorBuffer),fmt,args);
	va_end(args);

	printk(KERN_WARNING "AFFS warning (device %s): %s(): %s\n", sb->s_id,
		function,ErrorBuffer);
}

/* Check if the name is valid for a affs object. */

int
affs_check_name(const unsigned char *name, int len)
{
	int	 i;

	if (len > 30)
#ifdef AFFS_NO_TRUNCATE
		return -ENAMETOOLONG;
#else
		len = 30;
#endif

	for (i = 0; i < len; i++) {
		if (name[i] < ' ' || name[i] == ':'
		    || (name[i] > 0x7e && name[i] < 0xa0))
			return -EINVAL;
	}

	return 0;
}

/* This function copies name to bstr, with at most 30
 * characters length. The bstr will be prepended by
 * a length byte.
 * NOTE: The name will must be already checked by
 *       affs_check_name()!
 */

int
affs_copy_name(unsigned char *bstr, struct dentry *dentry)
{
	int len = min(dentry->d_name.len, 30u);

	*bstr++ = len;
	memcpy(bstr, dentry->d_name.name, len);
	return len;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/affs/amigaffs.c
	3	*
	4	* (c) 1996 Hans-Joachim Widmaier - Rewritten
	5	*
	6	* (C) 1993 Ray Burr - Amiga FFS filesystem.
	7	*
	8	* Please send bug reports to: hjw@zvw.de
	9	*/
	10
	11	#include "affs.h"
	12
	13	extern struct timezone sys_tz;
	14
	15	static char ErrorBuffer[256];
	16
	17	/*
	18	* Functions for accessing Amiga-FFS structures.
	19	*/
	20
	21
	22	/* Insert a header block bh into the directory dir
	23	* caller must hold AFFS_DIR->i_hash_lock!
	24	*/
	25
	26	int
	27	affs_insert_hash(struct inode dir, struct buffer_head bh)
	28	{
	29	struct super_block *sb = dir->i_sb;
	30	struct buffer_head *dir_bh;
	31	u32 ino, hash_ino;
	32	int offset;
	33
	34	ino = bh->b_blocknr;
	35	offset = affs_hash_name(sb, AFFS_TAIL(sb, bh)->name + 1, AFFS_TAIL(sb, bh)->name[0]);
	36
	37	pr_debug("AFFS: insert_hash(dir=%u, ino=%d)\n", (u32)dir->i_ino, ino);
	38
	39	dir_bh = affs_bread(sb, dir->i_ino);
	40	if (!dir_bh)
	41	return -EIO;
	42
	43	hash_ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[offset]);
	44	while (hash_ino) {
	45	affs_brelse(dir_bh);
	46	dir_bh = affs_bread(sb, hash_ino);
	47	if (!dir_bh)
	48	return -EIO;
	49	hash_ino = be32_to_cpu(AFFS_TAIL(sb, dir_bh)->hash_chain);
	50	}
	51	AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
	52	AFFS_TAIL(sb, bh)->hash_chain = 0;
	53	affs_fix_checksum(sb, bh);
	54
	55	if (dir->i_ino == dir_bh->b_blocknr)
	56	AFFS_HEAD(dir_bh)->table[offset] = cpu_to_be32(ino);
	57	else
	58	AFFS_TAIL(sb, dir_bh)->hash_chain = cpu_to_be32(ino);
	59
	60	affs_adjust_checksum(dir_bh, ino);
	61	mark_buffer_dirty_inode(dir_bh, dir);
	62	affs_brelse(dir_bh);
	63
	64	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
65	dir->i_version++;
66	mark_inode_dirty(dir);
67
68	return 0;
69	}
70
71	/* Remove a header block from its directory.
72	* caller must hold AFFS_DIR->i_hash_lock!
73	*/
74
75	int
76	affs_remove_hash(struct inode dir, struct buffer_head rem_bh)
77	{
78	struct super_block *sb;
79	struct buffer_head *bh;
80	u32 rem_ino, hash_ino;
81	__be32 ino;
82	int offset, retval;
83
84	sb = dir->i_sb;
85	rem_ino = rem_bh->b_blocknr;
86	offset = affs_hash_name(sb, AFFS_TAIL(sb, rem_bh)->name+1, AFFS_TAIL(sb, rem_bh)->name[0]);
87	pr_debug("AFFS: remove_hash(dir=%d, ino=%d, hashval=%d)\n", (u32)dir->i_ino, rem_ino, offset);
88
89	bh = affs_bread(sb, dir->i_ino);
90	if (!bh)
91	return -EIO;
92
93	retval = -ENOENT;
94	hash_ino = be32_to_cpu(AFFS_HEAD(bh)->table[offset]);
95	while (hash_ino) {
96	if (hash_ino == rem_ino) {
97	ino = AFFS_TAIL(sb, rem_bh)->hash_chain;
98	if (dir->i_ino == bh->b_blocknr)
99	AFFS_HEAD(bh)->table[offset] = ino;
100	else
101	AFFS_TAIL(sb, bh)->hash_chain = ino;
102	affs_adjust_checksum(bh, be32_to_cpu(ino) - hash_ino);
103	mark_buffer_dirty_inode(bh, dir);
104	AFFS_TAIL(sb, rem_bh)->parent = 0;
105	retval = 0;
106	break;
107	}
108	affs_brelse(bh);
109	bh = affs_bread(sb, hash_ino);
110	if (!bh)
111	return -EIO;
112	hash_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain);
113	}
114
115	affs_brelse(bh);
116
117	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
118	dir->i_version++;
119	mark_inode_dirty(dir);
120
121	return retval;
122	}
123
124	static void
12447c40	125	affs_fix_dcache(struct inode *inode, u32 entry_ino)
1da177e4	126	{
12447c40	127	struct dentry *dentry;
873feea0	128	spin_lock(&inode->i_lock);
b67bfe0d	129	hlist_for_each_entry(dentry, &inode->i_dentry, d_alias) {
1da177e4	130	if (entry_ino == (u32)(long)dentry->d_fsdata) {
12447c40	131	dentry->d_fsdata = (void *)inode->i_ino;
1da177e4 LT	132	break;
1da177e4 LT	133	}
1da177e4	134	}
873feea0	135	spin_unlock(&inode->i_lock);
1da177e4 LT	136	}
	137
	138
	139	/* Remove header from link chain */
	140
	141	static int
	142	affs_remove_link(struct dentry *dentry)
	143	{
	144	struct inode dir, inode = dentry->d_inode;
	145	struct super_block *sb = inode->i_sb;
	146	struct buffer_head bh = NULL, link_bh = NULL;
	147	u32 link_ino, ino;
	148	int retval;
	149
	150	pr_debug("AFFS: remove_link(key=%ld)\n", inode->i_ino);
	151	retval = -EIO;
	152	bh = affs_bread(sb, inode->i_ino);
	153	if (!bh)
	154	goto done;
	155
	156	link_ino = (u32)(long)dentry->d_fsdata;
	157	if (inode->i_ino == link_ino) {
	158	/* we can't remove the head of the link, as its blocknr is still used as ino,
	159	* so we remove the block of the first link instead.
	160	*/
	161	link_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain);
	162	link_bh = affs_bread(sb, link_ino);
	163	if (!link_bh)
	164	goto done;
	165
210f8559 DH	166	dir = affs_iget(sb, be32_to_cpu(AFFS_TAIL(sb, link_bh)->parent));
	167	if (IS_ERR(dir)) {
	168	retval = PTR_ERR(dir);
1da177e4	169	goto done;
210f8559	170	}
1da177e4 LT	171
1da177e4 LT	172	affs_lock_dir(dir);
12447c40 AV	173	/*
	174	* if there's a dentry for that block, make it
	175	* refer to inode itself.
	176	*/
	177	affs_fix_dcache(inode, link_ino);
1da177e4	178	retval = affs_remove_hash(dir, link_bh);
ec1ab0ab CH	179	if (retval) {
ec1ab0ab CH	180	affs_unlock_dir(dir);
1da177e4	181	goto done;
ec1ab0ab	182	}
1da177e4 LT	183	mark_buffer_dirty_inode(link_bh, inode);
	184
	185	memcpy(AFFS_TAIL(sb, bh)->name, AFFS_TAIL(sb, link_bh)->name, 32);
	186	retval = affs_insert_hash(dir, bh);
ec1ab0ab CH	187	if (retval) {
ec1ab0ab CH	188	affs_unlock_dir(dir);
1da177e4	189	goto done;
ec1ab0ab	190	}
1da177e4 LT	191	mark_buffer_dirty_inode(bh, inode);
	192
	193	affs_unlock_dir(dir);
	194	iput(dir);
	195	} else {
	196	link_bh = affs_bread(sb, link_ino);
	197	if (!link_bh)
	198	goto done;
	199	}
	200
	201	while ((ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain)) != 0) {
	202	if (ino == link_ino) {
	203	__be32 ino2 = AFFS_TAIL(sb, link_bh)->link_chain;
	204	AFFS_TAIL(sb, bh)->link_chain = ino2;
	205	affs_adjust_checksum(bh, be32_to_cpu(ino2) - link_ino);
	206	mark_buffer_dirty_inode(bh, inode);
	207	retval = 0;
	208	/* Fix the link count, if bh is a normal header block without links */
	209	switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
	210	case ST_LINKDIR:
	211	case ST_LINKFILE:
	212	break;
	213	default:
	214	if (!AFFS_TAIL(sb, bh)->link_chain)
bfe86848	215	set_nlink(inode, 1);
1da177e4 LT	216	}
	217	affs_free_block(sb, link_ino);
	218	goto done;
	219	}
	220	affs_brelse(bh);
	221	bh = affs_bread(sb, ino);
	222	if (!bh)
	223	goto done;
	224	}
	225	retval = -ENOENT;
	226	done:
	227	affs_brelse(link_bh);
	228	affs_brelse(bh);
	229	return retval;
	230	}
	231
	232
	233	static int
	234	affs_empty_dir(struct inode *inode)
	235	{
	236	struct super_block *sb = inode->i_sb;
	237	struct buffer_head *bh;
	238	int retval, size;
	239
	240	retval = -EIO;
	241	bh = affs_bread(sb, inode->i_ino);
	242	if (!bh)
	243	goto done;
	244
	245	retval = -ENOTEMPTY;
	246	for (size = AFFS_SB(sb)->s_hashsize - 1; size >= 0; size--)
	247	if (AFFS_HEAD(bh)->table[size])
	248	goto not_empty;
	249	retval = 0;
	250	not_empty:
	251	affs_brelse(bh);
	252	done:
	253	return retval;
	254	}
	255
	256
	257	/* Remove a filesystem object. If the object to be removed has
	258	* links to it, one of the links must be changed to inherit
	259	* the file or directory. As above, any inode will do.
	260	* The buffer will not be freed. If the header is a link, the
	261	* block will be marked as free.
	262	* This function returns a negative error number in case of
	263	* an error, else 0 if the inode is to be deleted or 1 if not.
	264	*/
	265
	266	int
	267	affs_remove_header(struct dentry *dentry)
	268	{
	269	struct super_block *sb;
	270	struct inode inode, dir;
	271	struct buffer_head *bh = NULL;
	272	int retval;
	273
	274	dir = dentry->d_parent->d_inode;
	275	sb = dir->i_sb;
	276
	277	retval = -ENOENT;
	278	inode = dentry->d_inode;
	279	if (!inode)
280	goto done;
281
282	pr_debug("AFFS: remove_header(key=%ld)\n", inode->i_ino);
283	retval = -EIO;
284	bh = affs_bread(sb, (u32)(long)dentry->d_fsdata);
285	if (!bh)
286	goto done;
287
288	affs_lock_link(inode);
289	affs_lock_dir(dir);
290	switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
291	case ST_USERDIR:
292	/* if we ever want to support links to dirs
293	* i_hash_lock of the inode must only be
294	* taken after some checks
295	*/
296	affs_lock_dir(inode);
297	retval = affs_empty_dir(inode);
298	affs_unlock_dir(inode);
299	if (retval)
300	goto done_unlock;
301	break;
302	default:
303	break;
304	}
305
306	retval = affs_remove_hash(dir, bh);
307	if (retval)
308	goto done_unlock;
309	mark_buffer_dirty_inode(bh, inode);
310
311	affs_unlock_dir(dir);
312
313	if (inode->i_nlink > 1)
314	retval = affs_remove_link(dentry);
315	else
6d6b77f1	316	clear_nlink(inode);
1da177e4 LT	317	affs_unlock_link(inode);
	318	inode->i_ctime = CURRENT_TIME_SEC;
	319	mark_inode_dirty(inode);
	320
	321	done:
	322	affs_brelse(bh);
	323	return retval;
	324
	325	done_unlock:
	326	affs_unlock_dir(dir);
	327	affs_unlock_link(inode);
	328	goto done;
	329	}
	330
	331	/* Checksum a block, do various consistency checks and optionally return
	332	the blocks type number. DATA points to the block. If their pointers
	333	are non-null, PTYPE and STYPE are set to the primary and secondary
	334	block types respectively, *HASHSIZE is set to the size of the hashtable
	335	(which lets us calculate the block size).
	336	Returns non-zero if the block is not consistent. */
	337
	338	u32
	339	affs_checksum_block(struct super_block sb, struct buffer_head bh)
	340	{
	341	__be32 ptr = (__be32 )bh->b_data;
	342	u32 sum;
	343	int bsize;
	344
	345	sum = 0;
	346	for (bsize = sb->s_blocksize / sizeof(__be32); bsize > 0; bsize--)
	347	sum += be32_to_cpu(*ptr++);
	348	return sum;
	349	}
	350
	351	/*
	352	* Calculate the checksum of a disk block and store it
	353	* at the indicated position.
	354	*/
	355
	356	void
	357	affs_fix_checksum(struct super_block sb, struct buffer_head bh)
	358	{
	359	int cnt = sb->s_blocksize / sizeof(__be32);
	360	__be32 ptr = (__be32 )bh->b_data;
	361	u32 checksum;
	362	__be32 *checksumptr;
	363
	364	checksumptr = ptr + 5;
	365	*checksumptr = 0;
	366	for (checksum = 0; cnt > 0; ptr++, cnt--)
	367	checksum += be32_to_cpu(*ptr);
	368	*checksumptr = cpu_to_be32(-checksum);
	369	}
	370
	371	void
	372	secs_to_datestamp(time_t secs, struct affs_date *ds)
	373	{
	374	u32 days;
	375	u32 minute;
	376
	377	secs -= sys_tz.tz_minuteswest * 60 + ((8 * 365 + 2) * 24 * 60 * 60);
	378	if (secs < 0)
	379	secs = 0;
	380	days = secs / 86400;
381	secs -= days * 86400;
382	minute = secs / 60;
383	secs -= minute * 60;
384
385	ds->days = cpu_to_be32(days);
386	ds->mins = cpu_to_be32(minute);
387	ds->ticks = cpu_to_be32(secs * 50);
388	}
389
a760b03d	390	umode_t
1da177e4 LT	391	prot_to_mode(u32 prot)
1da177e4 LT	392	{
a760b03d	393	umode_t mode = 0;
1da177e4 LT	394
	395	if (!(prot & FIBF_NOWRITE))
	396	mode \|= S_IWUSR;
	397	if (!(prot & FIBF_NOREAD))
	398	mode \|= S_IRUSR;
	399	if (!(prot & FIBF_NOEXECUTE))
	400	mode \|= S_IXUSR;
	401	if (prot & FIBF_GRP_WRITE)
	402	mode \|= S_IWGRP;
	403	if (prot & FIBF_GRP_READ)
	404	mode \|= S_IRGRP;
	405	if (prot & FIBF_GRP_EXECUTE)
	406	mode \|= S_IXGRP;
	407	if (prot & FIBF_OTR_WRITE)
	408	mode \|= S_IWOTH;
	409	if (prot & FIBF_OTR_READ)
	410	mode \|= S_IROTH;
	411	if (prot & FIBF_OTR_EXECUTE)
	412	mode \|= S_IXOTH;
	413
	414	return mode;
	415	}
	416
	417	void
	418	mode_to_prot(struct inode *inode)
	419	{
	420	u32 prot = AFFS_I(inode)->i_protect;
a760b03d	421	umode_t mode = inode->i_mode;
1da177e4 LT	422
	423	if (!(mode & S_IXUSR))
	424	prot \|= FIBF_NOEXECUTE;
	425	if (!(mode & S_IRUSR))
	426	prot \|= FIBF_NOREAD;
	427	if (!(mode & S_IWUSR))
	428	prot \|= FIBF_NOWRITE;
	429	if (mode & S_IXGRP)
	430	prot \|= FIBF_GRP_EXECUTE;
	431	if (mode & S_IRGRP)
	432	prot \|= FIBF_GRP_READ;
	433	if (mode & S_IWGRP)
	434	prot \|= FIBF_GRP_WRITE;
	435	if (mode & S_IXOTH)
	436	prot \|= FIBF_OTR_EXECUTE;
	437	if (mode & S_IROTH)
	438	prot \|= FIBF_OTR_READ;
	439	if (mode & S_IWOTH)
	440	prot \|= FIBF_OTR_WRITE;
	441
	442	AFFS_I(inode)->i_protect = prot;
	443	}
	444
	445	void
	446	affs_error(struct super_block sb, const char function, const char *fmt, ...)
	447	{
	448	va_list args;
	449
	450	va_start(args,fmt);
4a6e617a	451	vsnprintf(ErrorBuffer,sizeof(ErrorBuffer),fmt,args);
1da177e4 LT	452	va_end(args);
	453
	454	printk(KERN_CRIT "AFFS error (device %s): %s(): %s\n", sb->s_id,
	455	function,ErrorBuffer);
	456	if (!(sb->s_flags & MS_RDONLY))
	457	printk(KERN_WARNING "AFFS: Remounting filesystem read-only\n");
	458	sb->s_flags \|= MS_RDONLY;
	459	}
	460
	461	void
	462	affs_warning(struct super_block sb, const char function, const char *fmt, ...)
	463	{
	464	va_list args;
	465
	466	va_start(args,fmt);
4a6e617a	467	vsnprintf(ErrorBuffer,sizeof(ErrorBuffer),fmt,args);
1da177e4 LT	468	va_end(args);
	469
	470	printk(KERN_WARNING "AFFS warning (device %s): %s(): %s\n", sb->s_id,
	471	function,ErrorBuffer);
	472	}
	473
	474	/* Check if the name is valid for a affs object. */
	475
	476	int
	477	affs_check_name(const unsigned char *name, int len)
	478	{
	479	int i;
	480
	481	if (len > 30)
	482	#ifdef AFFS_NO_TRUNCATE
	483	return -ENAMETOOLONG;
	484	#else
	485	len = 30;
	486	#endif
	487
	488	for (i = 0; i < len; i++) {
	489	if (name[i] < ' ' \|\| name[i] == ':'
	490	\|\| (name[i] > 0x7e && name[i] < 0xa0))
	491	return -EINVAL;
	492	}
	493
	494	return 0;
	495	}
	496
	497	/* This function copies name to bstr, with at most 30
	498	* characters length. The bstr will be prepended by
	499	* a length byte.
	500	* NOTE: The name will must be already checked by
	501	* affs_check_name()!
	502	*/
	503
	504	int
	505	affs_copy_name(unsigned char bstr, struct dentry dentry)
	506	{
	507	int len = min(dentry->d_name.len, 30u);
	508
	509	*bstr++ = len;
	510	memcpy(bstr, dentry->d_name.name, len);
	511	return len;
	512	}