[linux-2.6-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"

/*
 * 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("%s(dir=%lu, ino=%d)\n", __func__, 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("%s(dir=%lu, ino=%d, hashval=%d)\n", __func__, 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_u.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 = d_inode(dentry);
	struct super_block *sb = inode->i_sb;
	struct buffer_head *bh, *link_bh = NULL;
	u32 link_ino, ino;
	int retval;

	pr_debug("%s(key=%ld)\n", __func__, 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 = d_inode(dentry->d_parent);
	sb = dir->i_sb;

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

	pr_debug("%s(key=%ld)\n", __func__, 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, ...)
{
	struct va_format vaf;
	va_list args;

	va_start(args, fmt);
	vaf.fmt = fmt;
	vaf.va = &args;
	pr_crit("error (device %s): %s(): %pV\n", sb->s_id, function, &vaf);
	if (!(sb->s_flags & MS_RDONLY))
		pr_warn("Remounting filesystem read-only\n");
	sb->s_flags |= MS_RDONLY;
	va_end(args);
}

void
affs_warning(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;
	pr_warn("(device %s): %s(): %pV\n", sb->s_id, function, &vaf);
	va_end(args);
}

bool
affs_nofilenametruncate(const struct dentry *dentry)
{
	struct inode *inode = d_inode(dentry);

	return affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_NO_TRUNCATE);
}

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

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

	if (len > AFFSNAMEMAX) {
		if (notruncate)
			return -ENAMETOOLONG;
		len = AFFSNAMEMAX;
	}
	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)
{
	u32 len = min(dentry->d_name.len, AFFSNAMEMAX);

	*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
1da177e4 LT	13	/*
	14	* Functions for accessing Amiga-FFS structures.
	15	*/
	16
	17
	18	/* Insert a header block bh into the directory dir
	19	* caller must hold AFFS_DIR->i_hash_lock!
	20	*/
	21
	22	int
	23	affs_insert_hash(struct inode dir, struct buffer_head bh)
	24	{
	25	struct super_block *sb = dir->i_sb;
	26	struct buffer_head *dir_bh;
	27	u32 ino, hash_ino;
	28	int offset;
	29
	30	ino = bh->b_blocknr;
	31	offset = affs_hash_name(sb, AFFS_TAIL(sb, bh)->name + 1, AFFS_TAIL(sb, bh)->name[0]);
	32
08fe100d	33	pr_debug("%s(dir=%lu, ino=%d)\n", __func__, dir->i_ino, ino);
1da177e4 LT	34
	35	dir_bh = affs_bread(sb, dir->i_ino);
	36	if (!dir_bh)
	37	return -EIO;
	38
	39	hash_ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[offset]);
	40	while (hash_ino) {
	41	affs_brelse(dir_bh);
	42	dir_bh = affs_bread(sb, hash_ino);
	43	if (!dir_bh)
	44	return -EIO;
	45	hash_ino = be32_to_cpu(AFFS_TAIL(sb, dir_bh)->hash_chain);
	46	}
	47	AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
	48	AFFS_TAIL(sb, bh)->hash_chain = 0;
	49	affs_fix_checksum(sb, bh);
	50
	51	if (dir->i_ino == dir_bh->b_blocknr)
	52	AFFS_HEAD(dir_bh)->table[offset] = cpu_to_be32(ino);
	53	else
	54	AFFS_TAIL(sb, dir_bh)->hash_chain = cpu_to_be32(ino);
	55
	56	affs_adjust_checksum(dir_bh, ino);
	57	mark_buffer_dirty_inode(dir_bh, dir);
	58	affs_brelse(dir_bh);
	59
	60	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
	61	dir->i_version++;
	62	mark_inode_dirty(dir);
	63
	64	return 0;
	65	}
	66
	67	/* Remove a header block from its directory.
	68	* caller must hold AFFS_DIR->i_hash_lock!
	69	*/
	70
	71	int
	72	affs_remove_hash(struct inode dir, struct buffer_head rem_bh)
	73	{
	74	struct super_block *sb;
	75	struct buffer_head *bh;
	76	u32 rem_ino, hash_ino;
	77	__be32 ino;
	78	int offset, retval;
	79
	80	sb = dir->i_sb;
	81	rem_ino = rem_bh->b_blocknr;
	82	offset = affs_hash_name(sb, AFFS_TAIL(sb, rem_bh)->name+1, AFFS_TAIL(sb, rem_bh)->name[0]);
08fe100d GU	83	pr_debug("%s(dir=%lu, ino=%d, hashval=%d)\n", __func__, dir->i_ino,
08fe100d GU	84	rem_ino, offset);
1da177e4 LT	85
	86	bh = affs_bread(sb, dir->i_ino);
	87	if (!bh)
	88	return -EIO;
	89
	90	retval = -ENOENT;
	91	hash_ino = be32_to_cpu(AFFS_HEAD(bh)->table[offset]);
	92	while (hash_ino) {
	93	if (hash_ino == rem_ino) {
	94	ino = AFFS_TAIL(sb, rem_bh)->hash_chain;
	95	if (dir->i_ino == bh->b_blocknr)
	96	AFFS_HEAD(bh)->table[offset] = ino;
	97	else
	98	AFFS_TAIL(sb, bh)->hash_chain = ino;
	99	affs_adjust_checksum(bh, be32_to_cpu(ino) - hash_ino);
	100	mark_buffer_dirty_inode(bh, dir);
	101	AFFS_TAIL(sb, rem_bh)->parent = 0;
	102	retval = 0;
	103	break;
	104	}
	105	affs_brelse(bh);
	106	bh = affs_bread(sb, hash_ino);
	107	if (!bh)
	108	return -EIO;
	109	hash_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain);
	110	}
	111
	112	affs_brelse(bh);
	113
	114	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
	115	dir->i_version++;
	116	mark_inode_dirty(dir);
	117
	118	return retval;
	119	}
	120
	121	static void
12447c40	122	affs_fix_dcache(struct inode *inode, u32 entry_ino)
1da177e4	123	{
12447c40	124	struct dentry *dentry;
873feea0	125	spin_lock(&inode->i_lock);
946e51f2	126	hlist_for_each_entry(dentry, &inode->i_dentry, d_u.d_alias) {
1da177e4	127	if (entry_ino == (u32)(long)dentry->d_fsdata) {
12447c40	128	dentry->d_fsdata = (void *)inode->i_ino;
1da177e4 LT	129	break;
1da177e4 LT	130	}
1da177e4	131	}
873feea0	132	spin_unlock(&inode->i_lock);
1da177e4 LT	133	}
	134
	135
	136	/* Remove header from link chain */
	137
	138	static int
	139	affs_remove_link(struct dentry *dentry)
	140	{
2b0143b5	141	struct inode dir, inode = d_inode(dentry);
1da177e4	142	struct super_block *sb = inode->i_sb;
4709187e	143	struct buffer_head bh, link_bh = NULL;
1da177e4 LT	144	u32 link_ino, ino;
	145	int retval;
	146
9606d9aa	147	pr_debug("%s(key=%ld)\n", __func__, inode->i_ino);
1da177e4 LT	148	retval = -EIO;
	149	bh = affs_bread(sb, inode->i_ino);
	150	if (!bh)
	151	goto done;
	152
	153	link_ino = (u32)(long)dentry->d_fsdata;
	154	if (inode->i_ino == link_ino) {
	155	/* we can't remove the head of the link, as its blocknr is still used as ino,
	156	* so we remove the block of the first link instead.
	157	*/
	158	link_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain);
	159	link_bh = affs_bread(sb, link_ino);
	160	if (!link_bh)
	161	goto done;
	162
210f8559 DH	163	dir = affs_iget(sb, be32_to_cpu(AFFS_TAIL(sb, link_bh)->parent));
	164	if (IS_ERR(dir)) {
	165	retval = PTR_ERR(dir);
1da177e4	166	goto done;
210f8559	167	}
1da177e4 LT	168
1da177e4 LT	169	affs_lock_dir(dir);
12447c40 AV	170	/*
	171	* if there's a dentry for that block, make it
	172	* refer to inode itself.
	173	*/
	174	affs_fix_dcache(inode, link_ino);
1da177e4	175	retval = affs_remove_hash(dir, link_bh);
ec1ab0ab CH	176	if (retval) {
ec1ab0ab CH	177	affs_unlock_dir(dir);
1da177e4	178	goto done;
ec1ab0ab	179	}
1da177e4 LT	180	mark_buffer_dirty_inode(link_bh, inode);
	181
	182	memcpy(AFFS_TAIL(sb, bh)->name, AFFS_TAIL(sb, link_bh)->name, 32);
	183	retval = affs_insert_hash(dir, bh);
ec1ab0ab CH	184	if (retval) {
ec1ab0ab CH	185	affs_unlock_dir(dir);
1da177e4	186	goto done;
ec1ab0ab	187	}
1da177e4 LT	188	mark_buffer_dirty_inode(bh, inode);
	189
	190	affs_unlock_dir(dir);
	191	iput(dir);
	192	} else {
	193	link_bh = affs_bread(sb, link_ino);
	194	if (!link_bh)
	195	goto done;
	196	}
	197
	198	while ((ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain)) != 0) {
	199	if (ino == link_ino) {
	200	__be32 ino2 = AFFS_TAIL(sb, link_bh)->link_chain;
	201	AFFS_TAIL(sb, bh)->link_chain = ino2;
	202	affs_adjust_checksum(bh, be32_to_cpu(ino2) - link_ino);
	203	mark_buffer_dirty_inode(bh, inode);
	204	retval = 0;
	205	/* Fix the link count, if bh is a normal header block without links */
	206	switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
	207	case ST_LINKDIR:
	208	case ST_LINKFILE:
	209	break;
	210	default:
	211	if (!AFFS_TAIL(sb, bh)->link_chain)
bfe86848	212	set_nlink(inode, 1);
1da177e4 LT	213	}
	214	affs_free_block(sb, link_ino);
	215	goto done;
	216	}
	217	affs_brelse(bh);
	218	bh = affs_bread(sb, ino);
	219	if (!bh)
	220	goto done;
	221	}
	222	retval = -ENOENT;
	223	done:
	224	affs_brelse(link_bh);
	225	affs_brelse(bh);
	226	return retval;
	227	}
	228
	229
	230	static int
	231	affs_empty_dir(struct inode *inode)
	232	{
	233	struct super_block *sb = inode->i_sb;
	234	struct buffer_head *bh;
	235	int retval, size;
	236
	237	retval = -EIO;
	238	bh = affs_bread(sb, inode->i_ino);
	239	if (!bh)
	240	goto done;
	241
	242	retval = -ENOTEMPTY;
	243	for (size = AFFS_SB(sb)->s_hashsize - 1; size >= 0; size--)
	244	if (AFFS_HEAD(bh)->table[size])
	245	goto not_empty;
	246	retval = 0;
	247	not_empty:
	248	affs_brelse(bh);
	249	done:
	250	return retval;
	251	}
	252
	253
	254	/* Remove a filesystem object. If the object to be removed has
	255	* links to it, one of the links must be changed to inherit
	256	* the file or directory. As above, any inode will do.
	257	* The buffer will not be freed. If the header is a link, the
	258	* block will be marked as free.
	259	* This function returns a negative error number in case of
	260	* an error, else 0 if the inode is to be deleted or 1 if not.
	261	*/
	262
	263	int
	264	affs_remove_header(struct dentry *dentry)
	265	{
	266	struct super_block *sb;
	267	struct inode inode, dir;
	268	struct buffer_head *bh = NULL;
	269	int retval;
	270
2b0143b5	271	dir = d_inode(dentry->d_parent);
1da177e4 LT	272	sb = dir->i_sb;
	273
	274	retval = -ENOENT;
2b0143b5	275	inode = d_inode(dentry);
1da177e4 LT	276	if (!inode)
	277	goto done;
	278
9606d9aa	279	pr_debug("%s(key=%ld)\n", __func__, inode->i_ino);
1da177e4 LT	280	retval = -EIO;
	281	bh = affs_bread(sb, (u32)(long)dentry->d_fsdata);
	282	if (!bh)
	283	goto done;
	284
	285	affs_lock_link(inode);
	286	affs_lock_dir(dir);
	287	switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
	288	case ST_USERDIR:
	289	/* if we ever want to support links to dirs
	290	* i_hash_lock of the inode must only be
	291	* taken after some checks
	292	*/
	293	affs_lock_dir(inode);
	294	retval = affs_empty_dir(inode);
	295	affs_unlock_dir(inode);
	296	if (retval)
	297	goto done_unlock;
	298	break;
	299	default:
	300	break;
	301	}
	302
	303	retval = affs_remove_hash(dir, bh);
	304	if (retval)
	305	goto done_unlock;
	306	mark_buffer_dirty_inode(bh, inode);
	307
	308	affs_unlock_dir(dir);
	309
	310	if (inode->i_nlink > 1)
	311	retval = affs_remove_link(dentry);
	312	else
6d6b77f1	313	clear_nlink(inode);
1da177e4 LT	314	affs_unlock_link(inode);
	315	inode->i_ctime = CURRENT_TIME_SEC;
	316	mark_inode_dirty(inode);
	317
	318	done:
	319	affs_brelse(bh);
	320	return retval;
	321
	322	done_unlock:
	323	affs_unlock_dir(dir);
	324	affs_unlock_link(inode);
	325	goto done;
	326	}
	327
	328	/* Checksum a block, do various consistency checks and optionally return
	329	the blocks type number. DATA points to the block. If their pointers
	330	are non-null, PTYPE and STYPE are set to the primary and secondary
	331	block types respectively, *HASHSIZE is set to the size of the hashtable
	332	(which lets us calculate the block size).
	333	Returns non-zero if the block is not consistent. */
	334
	335	u32
	336	affs_checksum_block(struct super_block sb, struct buffer_head bh)
	337	{
	338	__be32 ptr = (__be32 )bh->b_data;
	339	u32 sum;
	340	int bsize;
	341
	342	sum = 0;
	343	for (bsize = sb->s_blocksize / sizeof(__be32); bsize > 0; bsize--)
	344	sum += be32_to_cpu(*ptr++);
	345	return sum;
	346	}
	347
	348	/*
	349	* Calculate the checksum of a disk block and store it
	350	* at the indicated position.
	351	*/
	352
	353	void
	354	affs_fix_checksum(struct super_block sb, struct buffer_head bh)
	355	{
	356	int cnt = sb->s_blocksize / sizeof(__be32);
	357	__be32 ptr = (__be32 )bh->b_data;
	358	u32 checksum;
	359	__be32 *checksumptr;
	360
	361	checksumptr = ptr + 5;
	362	*checksumptr = 0;
	363	for (checksum = 0; cnt > 0; ptr++, cnt--)
	364	checksum += be32_to_cpu(*ptr);
	365	*checksumptr = cpu_to_be32(-checksum);
	366	}
	367
	368	void
	369	secs_to_datestamp(time_t secs, struct affs_date *ds)
	370	{
	371	u32 days;
	372	u32 minute;
	373
	374	secs -= sys_tz.tz_minuteswest * 60 + ((8 * 365 + 2) * 24 * 60 * 60);
	375	if (secs < 0)
	376	secs = 0;
	377	days = secs / 86400;
378	secs -= days * 86400;
379	minute = secs / 60;
380	secs -= minute * 60;
381
382	ds->days = cpu_to_be32(days);
383	ds->mins = cpu_to_be32(minute);
384	ds->ticks = cpu_to_be32(secs * 50);
385	}
386
a760b03d	387	umode_t
1da177e4 LT	388	prot_to_mode(u32 prot)
1da177e4 LT	389	{
a760b03d	390	umode_t mode = 0;
1da177e4 LT	391
	392	if (!(prot & FIBF_NOWRITE))
	393	mode \|= S_IWUSR;
	394	if (!(prot & FIBF_NOREAD))
	395	mode \|= S_IRUSR;
	396	if (!(prot & FIBF_NOEXECUTE))
	397	mode \|= S_IXUSR;
	398	if (prot & FIBF_GRP_WRITE)
	399	mode \|= S_IWGRP;
	400	if (prot & FIBF_GRP_READ)
	401	mode \|= S_IRGRP;
	402	if (prot & FIBF_GRP_EXECUTE)
	403	mode \|= S_IXGRP;
	404	if (prot & FIBF_OTR_WRITE)
	405	mode \|= S_IWOTH;
	406	if (prot & FIBF_OTR_READ)
	407	mode \|= S_IROTH;
	408	if (prot & FIBF_OTR_EXECUTE)
	409	mode \|= S_IXOTH;
	410
	411	return mode;
	412	}
	413
	414	void
	415	mode_to_prot(struct inode *inode)
	416	{
	417	u32 prot = AFFS_I(inode)->i_protect;
a760b03d	418	umode_t mode = inode->i_mode;
1da177e4 LT	419
	420	if (!(mode & S_IXUSR))
	421	prot \|= FIBF_NOEXECUTE;
	422	if (!(mode & S_IRUSR))
	423	prot \|= FIBF_NOREAD;
	424	if (!(mode & S_IWUSR))
	425	prot \|= FIBF_NOWRITE;
	426	if (mode & S_IXGRP)
	427	prot \|= FIBF_GRP_EXECUTE;
	428	if (mode & S_IRGRP)
	429	prot \|= FIBF_GRP_READ;
	430	if (mode & S_IWGRP)
	431	prot \|= FIBF_GRP_WRITE;
	432	if (mode & S_IXOTH)
	433	prot \|= FIBF_OTR_EXECUTE;
	434	if (mode & S_IROTH)
	435	prot \|= FIBF_OTR_READ;
	436	if (mode & S_IWOTH)
	437	prot \|= FIBF_OTR_WRITE;
	438
	439	AFFS_I(inode)->i_protect = prot;
	440	}
	441
	442	void
	443	affs_error(struct super_block sb, const char function, const char *fmt, ...)
	444	{
1ee54b09 FF	445	struct va_format vaf;
1ee54b09 FF	446	va_list args;
1da177e4	447
1ee54b09 FF	448	va_start(args, fmt);
	449	vaf.fmt = fmt;
	450	vaf.va = &args;
	451	pr_crit("error (device %s): %s(): %pV\n", sb->s_id, function, &vaf);
1da177e4	452	if (!(sb->s_flags & MS_RDONLY))
0158de12	453	pr_warn("Remounting filesystem read-only\n");
1da177e4	454	sb->s_flags \|= MS_RDONLY;
1ee54b09	455	va_end(args);
1da177e4 LT	456	}
	457
	458	void
	459	affs_warning(struct super_block sb, const char function, const char *fmt, ...)
	460	{
1ee54b09 FF	461	struct va_format vaf;
1ee54b09 FF	462	va_list args;
1da177e4	463
1ee54b09 FF	464	va_start(args, fmt);
	465	vaf.fmt = fmt;
	466	vaf.va = &args;
	467	pr_warn("(device %s): %s(): %pV\n", sb->s_id, function, &vaf);
1da177e4	468	va_end(args);
1da177e4 LT	469	}
1da177e4 LT	470
8ca57722 FF	471	bool
	472	affs_nofilenametruncate(const struct dentry *dentry)
	473	{
2b0143b5	474	struct inode *inode = d_inode(dentry);
79bda4d5 FF	475
79bda4d5 FF	476	return affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_NO_TRUNCATE);
8ca57722 FF	477	}
8ca57722 FF	478
1da177e4 LT	479	/* Check if the name is valid for a affs object. */
	480
	481	int
8ca57722	482	affs_check_name(const unsigned char *name, int len, bool notruncate)
1da177e4 LT	483	{
	484	int i;
	485
f157853e	486	if (len > AFFSNAMEMAX) {
8ca57722 FF	487	if (notruncate)
8ca57722 FF	488	return -ENAMETOOLONG;
b4478e35	489	len = AFFSNAMEMAX;
8ca57722	490	}
1da177e4 LT	491	for (i = 0; i < len; i++) {
	492	if (name[i] < ' ' \|\| name[i] == ':'
	493	\|\| (name[i] > 0x7e && name[i] < 0xa0))
	494	return -EINVAL;
	495	}
	496
	497	return 0;
	498	}
	499
	500	/* This function copies name to bstr, with at most 30
	501	* characters length. The bstr will be prepended by
	502	* a length byte.
	503	* NOTE: The name will must be already checked by
	504	* affs_check_name()!
	505	*/
	506
	507	int
	508	affs_copy_name(unsigned char bstr, struct dentry dentry)
	509	{
f157853e	510	u32 len = min(dentry->d_name.len, AFFSNAMEMAX);
1da177e4 LT	511
	512	*bstr++ = len;
	513	memcpy(bstr, dentry->d_name.name, len);
	514	return len;
	515	}