[linux.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: [email protected]
 */

#include <linux/math64.h>
#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(dir);
	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(dir);
	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(inode);
	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(time64_t secs, struct affs_date *ds)
{
	u32	 days;
	u32	 minute;
	s32	 rem;

	secs -= sys_tz.tz_minuteswest * 60 + ((8 * 365 + 2) * 24 * 60 * 60);
	if (secs < 0)
		secs = 0;
	days    = div_s64_rem(secs, 86400, &rem);
	minute  = rem / 60;
	rem    -= minute * 60;

	ds->days = cpu_to_be32(days);
	ds->mins = cpu_to_be32(minute);
	ds->ticks = cpu_to_be32(rem * 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)
{
	return affs_test_opt(AFFS_SB(dentry->d_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: [email protected]
	9	*/
	10
db39c167	11	#include <linux/math64.h>
1da177e4 LT	12	#include "affs.h"
1da177e4 LT	13
1da177e4 LT	14	/*
	15	* Functions for accessing Amiga-FFS structures.
	16	*/
	17
	18
	19	/* Insert a header block bh into the directory dir
	20	* caller must hold AFFS_DIR->i_hash_lock!
	21	*/
	22
	23	int
	24	affs_insert_hash(struct inode dir, struct buffer_head bh)
	25	{
	26	struct super_block *sb = dir->i_sb;
	27	struct buffer_head *dir_bh;
	28	u32 ino, hash_ino;
	29	int offset;
	30
	31	ino = bh->b_blocknr;
	32	offset = affs_hash_name(sb, AFFS_TAIL(sb, bh)->name + 1, AFFS_TAIL(sb, bh)->name[0]);
	33
08fe100d	34	pr_debug("%s(dir=%lu, ino=%d)\n", __func__, dir->i_ino, ino);
1da177e4 LT	35
	36	dir_bh = affs_bread(sb, dir->i_ino);
	37	if (!dir_bh)
	38	return -EIO;
	39
	40	hash_ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[offset]);
	41	while (hash_ino) {
	42	affs_brelse(dir_bh);
	43	dir_bh = affs_bread(sb, hash_ino);
	44	if (!dir_bh)
	45	return -EIO;
	46	hash_ino = be32_to_cpu(AFFS_TAIL(sb, dir_bh)->hash_chain);
	47	}
	48	AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
	49	AFFS_TAIL(sb, bh)->hash_chain = 0;
	50	affs_fix_checksum(sb, bh);
	51
	52	if (dir->i_ino == dir_bh->b_blocknr)
	53	AFFS_HEAD(dir_bh)->table[offset] = cpu_to_be32(ino);
	54	else
	55	AFFS_TAIL(sb, dir_bh)->hash_chain = cpu_to_be32(ino);
	56
	57	affs_adjust_checksum(dir_bh, ino);
	58	mark_buffer_dirty_inode(dir_bh, dir);
	59	affs_brelse(dir_bh);
	60
02027d42	61	dir->i_mtime = dir->i_ctime = current_time(dir);
1da177e4 LT	62	dir->i_version++;
	63	mark_inode_dirty(dir);
	64
	65	return 0;
	66	}
	67
	68	/* Remove a header block from its directory.
	69	* caller must hold AFFS_DIR->i_hash_lock!
	70	*/
	71
	72	int
	73	affs_remove_hash(struct inode dir, struct buffer_head rem_bh)
	74	{
	75	struct super_block *sb;
	76	struct buffer_head *bh;
	77	u32 rem_ino, hash_ino;
	78	__be32 ino;
	79	int offset, retval;
	80
	81	sb = dir->i_sb;
	82	rem_ino = rem_bh->b_blocknr;
	83	offset = affs_hash_name(sb, AFFS_TAIL(sb, rem_bh)->name+1, AFFS_TAIL(sb, rem_bh)->name[0]);
08fe100d GU	84	pr_debug("%s(dir=%lu, ino=%d, hashval=%d)\n", __func__, dir->i_ino,
08fe100d GU	85	rem_ino, offset);
1da177e4 LT	86
	87	bh = affs_bread(sb, dir->i_ino);
	88	if (!bh)
	89	return -EIO;
	90
	91	retval = -ENOENT;
	92	hash_ino = be32_to_cpu(AFFS_HEAD(bh)->table[offset]);
	93	while (hash_ino) {
	94	if (hash_ino == rem_ino) {
	95	ino = AFFS_TAIL(sb, rem_bh)->hash_chain;
	96	if (dir->i_ino == bh->b_blocknr)
	97	AFFS_HEAD(bh)->table[offset] = ino;
	98	else
	99	AFFS_TAIL(sb, bh)->hash_chain = ino;
	100	affs_adjust_checksum(bh, be32_to_cpu(ino) - hash_ino);
	101	mark_buffer_dirty_inode(bh, dir);
	102	AFFS_TAIL(sb, rem_bh)->parent = 0;
	103	retval = 0;
	104	break;
	105	}
	106	affs_brelse(bh);
	107	bh = affs_bread(sb, hash_ino);
	108	if (!bh)
	109	return -EIO;
	110	hash_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain);
	111	}
	112
	113	affs_brelse(bh);
	114
02027d42	115	dir->i_mtime = dir->i_ctime = current_time(dir);
1da177e4 LT	116	dir->i_version++;
	117	mark_inode_dirty(dir);
	118
	119	return retval;
	120	}
	121
	122	static void
12447c40	123	affs_fix_dcache(struct inode *inode, u32 entry_ino)
1da177e4	124	{
12447c40	125	struct dentry *dentry;
873feea0	126	spin_lock(&inode->i_lock);
946e51f2	127	hlist_for_each_entry(dentry, &inode->i_dentry, d_u.d_alias) {
1da177e4	128	if (entry_ino == (u32)(long)dentry->d_fsdata) {
12447c40	129	dentry->d_fsdata = (void *)inode->i_ino;
1da177e4 LT	130	break;
1da177e4 LT	131	}
1da177e4	132	}
873feea0	133	spin_unlock(&inode->i_lock);
1da177e4 LT	134	}
	135
	136
	137	/* Remove header from link chain */
	138
	139	static int
	140	affs_remove_link(struct dentry *dentry)
	141	{
2b0143b5	142	struct inode dir, inode = d_inode(dentry);
1da177e4	143	struct super_block *sb = inode->i_sb;
4709187e	144	struct buffer_head bh, link_bh = NULL;
1da177e4 LT	145	u32 link_ino, ino;
	146	int retval;
	147
9606d9aa	148	pr_debug("%s(key=%ld)\n", __func__, inode->i_ino);
1da177e4 LT	149	retval = -EIO;
	150	bh = affs_bread(sb, inode->i_ino);
	151	if (!bh)
	152	goto done;
	153
	154	link_ino = (u32)(long)dentry->d_fsdata;
	155	if (inode->i_ino == link_ino) {
	156	/* we can't remove the head of the link, as its blocknr is still used as ino,
	157	* so we remove the block of the first link instead.
	158	*/
	159	link_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain);
	160	link_bh = affs_bread(sb, link_ino);
	161	if (!link_bh)
	162	goto done;
	163
210f8559 DH	164	dir = affs_iget(sb, be32_to_cpu(AFFS_TAIL(sb, link_bh)->parent));
	165	if (IS_ERR(dir)) {
	166	retval = PTR_ERR(dir);
1da177e4	167	goto done;
210f8559	168	}
1da177e4 LT	169
1da177e4 LT	170	affs_lock_dir(dir);
12447c40 AV	171	/*
	172	* if there's a dentry for that block, make it
	173	* refer to inode itself.
	174	*/
	175	affs_fix_dcache(inode, link_ino);
1da177e4	176	retval = affs_remove_hash(dir, link_bh);
ec1ab0ab CH	177	if (retval) {
ec1ab0ab CH	178	affs_unlock_dir(dir);
1da177e4	179	goto done;
ec1ab0ab	180	}
1da177e4 LT	181	mark_buffer_dirty_inode(link_bh, inode);
	182
	183	memcpy(AFFS_TAIL(sb, bh)->name, AFFS_TAIL(sb, link_bh)->name, 32);
	184	retval = affs_insert_hash(dir, bh);
ec1ab0ab CH	185	if (retval) {
ec1ab0ab CH	186	affs_unlock_dir(dir);
1da177e4	187	goto done;
ec1ab0ab	188	}
1da177e4 LT	189	mark_buffer_dirty_inode(bh, inode);
	190
	191	affs_unlock_dir(dir);
	192	iput(dir);
	193	} else {
	194	link_bh = affs_bread(sb, link_ino);
	195	if (!link_bh)
	196	goto done;
	197	}
	198
	199	while ((ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain)) != 0) {
	200	if (ino == link_ino) {
	201	__be32 ino2 = AFFS_TAIL(sb, link_bh)->link_chain;
	202	AFFS_TAIL(sb, bh)->link_chain = ino2;
	203	affs_adjust_checksum(bh, be32_to_cpu(ino2) - link_ino);
	204	mark_buffer_dirty_inode(bh, inode);
	205	retval = 0;
	206	/* Fix the link count, if bh is a normal header block without links */
	207	switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
	208	case ST_LINKDIR:
	209	case ST_LINKFILE:
	210	break;
	211	default:
	212	if (!AFFS_TAIL(sb, bh)->link_chain)
bfe86848	213	set_nlink(inode, 1);
1da177e4 LT	214	}
	215	affs_free_block(sb, link_ino);
	216	goto done;
	217	}
	218	affs_brelse(bh);
	219	bh = affs_bread(sb, ino);
	220	if (!bh)
	221	goto done;
	222	}
	223	retval = -ENOENT;
	224	done:
	225	affs_brelse(link_bh);
	226	affs_brelse(bh);
	227	return retval;
	228	}
	229
	230
	231	static int
	232	affs_empty_dir(struct inode *inode)
	233	{
	234	struct super_block *sb = inode->i_sb;
	235	struct buffer_head *bh;
	236	int retval, size;
	237
	238	retval = -EIO;
	239	bh = affs_bread(sb, inode->i_ino);
	240	if (!bh)
	241	goto done;
	242
	243	retval = -ENOTEMPTY;
	244	for (size = AFFS_SB(sb)->s_hashsize - 1; size >= 0; size--)
	245	if (AFFS_HEAD(bh)->table[size])
	246	goto not_empty;
	247	retval = 0;
	248	not_empty:
	249	affs_brelse(bh);
	250	done:
	251	return retval;
	252	}
	253
	254
	255	/* Remove a filesystem object. If the object to be removed has
	256	* links to it, one of the links must be changed to inherit
	257	* the file or directory. As above, any inode will do.
	258	* The buffer will not be freed. If the header is a link, the
	259	* block will be marked as free.
	260	* This function returns a negative error number in case of
	261	* an error, else 0 if the inode is to be deleted or 1 if not.
	262	*/
	263
	264	int
	265	affs_remove_header(struct dentry *dentry)
	266	{
	267	struct super_block *sb;
	268	struct inode inode, dir;
	269	struct buffer_head *bh = NULL;
	270	int retval;
	271
2b0143b5	272	dir = d_inode(dentry->d_parent);
1da177e4 LT	273	sb = dir->i_sb;
	274
	275	retval = -ENOENT;
2b0143b5	276	inode = d_inode(dentry);
1da177e4 LT	277	if (!inode)
	278	goto done;
	279
9606d9aa	280	pr_debug("%s(key=%ld)\n", __func__, inode->i_ino);
1da177e4 LT	281	retval = -EIO;
	282	bh = affs_bread(sb, (u32)(long)dentry->d_fsdata);
	283	if (!bh)
	284	goto done;
	285
	286	affs_lock_link(inode);
	287	affs_lock_dir(dir);
	288	switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
	289	case ST_USERDIR:
	290	/* if we ever want to support links to dirs
	291	* i_hash_lock of the inode must only be
	292	* taken after some checks
	293	*/
	294	affs_lock_dir(inode);
	295	retval = affs_empty_dir(inode);
	296	affs_unlock_dir(inode);
	297	if (retval)
	298	goto done_unlock;
	299	break;
	300	default:
	301	break;
	302	}
	303
	304	retval = affs_remove_hash(dir, bh);
	305	if (retval)
	306	goto done_unlock;
	307	mark_buffer_dirty_inode(bh, inode);
	308
	309	affs_unlock_dir(dir);
	310
	311	if (inode->i_nlink > 1)
	312	retval = affs_remove_link(dentry);
	313	else
6d6b77f1	314	clear_nlink(inode);
1da177e4	315	affs_unlock_link(inode);
02027d42	316	inode->i_ctime = current_time(inode);
1da177e4 LT	317	mark_inode_dirty(inode);
	318
	319	done:
	320	affs_brelse(bh);
	321	return retval;
	322
	323	done_unlock:
	324	affs_unlock_dir(dir);
	325	affs_unlock_link(inode);
	326	goto done;
	327	}
	328
	329	/* Checksum a block, do various consistency checks and optionally return
	330	the blocks type number. DATA points to the block. If their pointers
	331	are non-null, PTYPE and STYPE are set to the primary and secondary
	332	block types respectively, *HASHSIZE is set to the size of the hashtable
	333	(which lets us calculate the block size).
	334	Returns non-zero if the block is not consistent. */
	335
	336	u32
	337	affs_checksum_block(struct super_block sb, struct buffer_head bh)
	338	{
	339	__be32 ptr = (__be32 )bh->b_data;
	340	u32 sum;
	341	int bsize;
	342
	343	sum = 0;
	344	for (bsize = sb->s_blocksize / sizeof(__be32); bsize > 0; bsize--)
	345	sum += be32_to_cpu(*ptr++);
	346	return sum;
	347	}
	348
	349	/*
	350	* Calculate the checksum of a disk block and store it
	351	* at the indicated position.
	352	*/
	353
	354	void
	355	affs_fix_checksum(struct super_block sb, struct buffer_head bh)
	356	{
	357	int cnt = sb->s_blocksize / sizeof(__be32);
	358	__be32 ptr = (__be32 )bh->b_data;
	359	u32 checksum;
	360	__be32 *checksumptr;
	361
	362	checksumptr = ptr + 5;
	363	*checksumptr = 0;
	364	for (checksum = 0; cnt > 0; ptr++, cnt--)
	365	checksum += be32_to_cpu(*ptr);
	366	*checksumptr = cpu_to_be32(-checksum);
	367	}
	368
	369	void
db39c167	370	secs_to_datestamp(time64_t secs, struct affs_date *ds)
1da177e4 LT	371	{
	372	u32 days;
	373	u32 minute;
db39c167	374	s32 rem;
1da177e4 LT	375
	376	secs -= sys_tz.tz_minuteswest * 60 + ((8 * 365 + 2) * 24 * 60 * 60);
	377	if (secs < 0)
	378	secs = 0;
db39c167 D	379	days = div_s64_rem(secs, 86400, &rem);
	380	minute = rem / 60;
	381	rem -= minute * 60;
1da177e4 LT	382
	383	ds->days = cpu_to_be32(days);
	384	ds->mins = cpu_to_be32(minute);
db39c167	385	ds->ticks = cpu_to_be32(rem * 50);
1da177e4 LT	386	}
1da177e4 LT	387
a760b03d	388	umode_t
1da177e4 LT	389	prot_to_mode(u32 prot)
1da177e4 LT	390	{
a760b03d	391	umode_t mode = 0;
1da177e4 LT	392
	393	if (!(prot & FIBF_NOWRITE))
	394	mode \|= S_IWUSR;
	395	if (!(prot & FIBF_NOREAD))
	396	mode \|= S_IRUSR;
	397	if (!(prot & FIBF_NOEXECUTE))
	398	mode \|= S_IXUSR;
	399	if (prot & FIBF_GRP_WRITE)
	400	mode \|= S_IWGRP;
	401	if (prot & FIBF_GRP_READ)
	402	mode \|= S_IRGRP;
	403	if (prot & FIBF_GRP_EXECUTE)
	404	mode \|= S_IXGRP;
	405	if (prot & FIBF_OTR_WRITE)
	406	mode \|= S_IWOTH;
	407	if (prot & FIBF_OTR_READ)
	408	mode \|= S_IROTH;
	409	if (prot & FIBF_OTR_EXECUTE)
	410	mode \|= S_IXOTH;
	411
	412	return mode;
	413	}
	414
	415	void
	416	mode_to_prot(struct inode *inode)
	417	{
	418	u32 prot = AFFS_I(inode)->i_protect;
a760b03d	419	umode_t mode = inode->i_mode;
1da177e4 LT	420
	421	if (!(mode & S_IXUSR))
	422	prot \|= FIBF_NOEXECUTE;
	423	if (!(mode & S_IRUSR))
	424	prot \|= FIBF_NOREAD;
	425	if (!(mode & S_IWUSR))
	426	prot \|= FIBF_NOWRITE;
	427	if (mode & S_IXGRP)
	428	prot \|= FIBF_GRP_EXECUTE;
	429	if (mode & S_IRGRP)
	430	prot \|= FIBF_GRP_READ;
	431	if (mode & S_IWGRP)
	432	prot \|= FIBF_GRP_WRITE;
	433	if (mode & S_IXOTH)
	434	prot \|= FIBF_OTR_EXECUTE;
	435	if (mode & S_IROTH)
	436	prot \|= FIBF_OTR_READ;
	437	if (mode & S_IWOTH)
	438	prot \|= FIBF_OTR_WRITE;
	439
	440	AFFS_I(inode)->i_protect = prot;
	441	}
	442
	443	void
	444	affs_error(struct super_block sb, const char function, const char *fmt, ...)
	445	{
1ee54b09 FF	446	struct va_format vaf;
1ee54b09 FF	447	va_list args;
1da177e4	448
1ee54b09 FF	449	va_start(args, fmt);
	450	vaf.fmt = fmt;
	451	vaf.va = &args;
	452	pr_crit("error (device %s): %s(): %pV\n", sb->s_id, function, &vaf);
1da177e4	453	if (!(sb->s_flags & MS_RDONLY))
0158de12	454	pr_warn("Remounting filesystem read-only\n");
1da177e4	455	sb->s_flags \|= MS_RDONLY;
1ee54b09	456	va_end(args);
1da177e4 LT	457	}
	458
	459	void
	460	affs_warning(struct super_block sb, const char function, const char *fmt, ...)
	461	{
1ee54b09 FF	462	struct va_format vaf;
1ee54b09 FF	463	va_list args;
1da177e4	464
1ee54b09 FF	465	va_start(args, fmt);
	466	vaf.fmt = fmt;
	467	vaf.va = &args;
	468	pr_warn("(device %s): %s(): %pV\n", sb->s_id, function, &vaf);
1da177e4	469	va_end(args);
1da177e4 LT	470	}
1da177e4 LT	471
8ca57722 FF	472	bool
	473	affs_nofilenametruncate(const struct dentry *dentry)
	474	{
e0b3f595	475	return affs_test_opt(AFFS_SB(dentry->d_sb)->s_flags, SF_NO_TRUNCATE);
8ca57722 FF	476	}
8ca57722 FF	477
1da177e4 LT	478	/* Check if the name is valid for a affs object. */
	479
	480	int
8ca57722	481	affs_check_name(const unsigned char *name, int len, bool notruncate)
1da177e4 LT	482	{
	483	int i;
	484
f157853e	485	if (len > AFFSNAMEMAX) {
8ca57722 FF	486	if (notruncate)
8ca57722 FF	487	return -ENAMETOOLONG;
b4478e35	488	len = AFFSNAMEMAX;
8ca57722	489	}
1da177e4 LT	490	for (i = 0; i < len; i++) {
	491	if (name[i] < ' ' \|\| name[i] == ':'
	492	\|\| (name[i] > 0x7e && name[i] < 0xa0))
	493	return -EINVAL;
	494	}
	495
	496	return 0;
	497	}
	498
	499	/* This function copies name to bstr, with at most 30
	500	* characters length. The bstr will be prepended by
	501	* a length byte.
	502	* NOTE: The name will must be already checked by
	503	* affs_check_name()!
	504	*/
	505
	506	int
	507	affs_copy_name(unsigned char bstr, struct dentry dentry)
	508	{
f157853e	509	u32 len = min(dentry->d_name.len, AFFSNAMEMAX);
1da177e4 LT	510
	511	*bstr++ = len;
	512	memcpy(bstr, dentry->d_name.name, len);
	513	return len;
	514	}