[GitHub/LineageOS/android_kernel_motorola_exynos9610.git] / fs / affs / amigaffs.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  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 <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
affs_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
affs_prot_to_mode(u32 prot)
{
	umode_t mode = 0;

	if (!(prot & FIBF_NOWRITE))
		mode |= 0200;
	if (!(prot & FIBF_NOREAD))
		mode |= 0400;
	if (!(prot & FIBF_NOEXECUTE))
		mode |= 0100;
	if (prot & FIBF_GRP_WRITE)
		mode |= 0020;
	if (prot & FIBF_GRP_READ)
		mode |= 0040;
	if (prot & FIBF_GRP_EXECUTE)
		mode |= 0010;
	if (prot & FIBF_OTR_WRITE)
		mode |= 0002;
	if (prot & FIBF_OTR_READ)
		mode |= 0004;
	if (prot & FIBF_OTR_EXECUTE)
		mode |= 0001;

	return mode;
}

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

	if (!(mode & 0100))
		prot |= FIBF_NOEXECUTE;
	if (!(mode & 0400))
		prot |= FIBF_NOREAD;
	if (!(mode & 0200))
		prot |= FIBF_NOWRITE;
	if (mode & 0010)
		prot |= FIBF_GRP_EXECUTE;
	if (mode & 0040)
		prot |= FIBF_GRP_READ;
	if (mode & 0020)
		prot |= FIBF_GRP_WRITE;
	if (mode & 0001)
		prot |= FIBF_OTR_EXECUTE;
	if (mode & 0004)
		prot |= FIBF_OTR_READ;
	if (mode & 0002)
		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_rdonly(sb))
		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
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* linux/fs/affs/amigaffs.c
	4	*
	5	* (c) 1996 Hans-Joachim Widmaier - Rewritten
	6	*
	7	* (C) 1993 Ray Burr - Amiga FFS filesystem.
	8	*
	9	* Please send bug reports to: hjw@zvw.de
	10	*/
	11
db39c167	12	#include <linux/math64.h>
1da177e4 LT	13	#include "affs.h"
1da177e4 LT	14
1da177e4 LT	15	/*
	16	* Functions for accessing Amiga-FFS structures.
	17	*/
	18
	19
	20	/* Insert a header block bh into the directory dir
	21	* caller must hold AFFS_DIR->i_hash_lock!
	22	*/
	23
	24	int
	25	affs_insert_hash(struct inode dir, struct buffer_head bh)
	26	{
	27	struct super_block *sb = dir->i_sb;
	28	struct buffer_head *dir_bh;
	29	u32 ino, hash_ino;
	30	int offset;
	31
	32	ino = bh->b_blocknr;
	33	offset = affs_hash_name(sb, AFFS_TAIL(sb, bh)->name + 1, AFFS_TAIL(sb, bh)->name[0]);
	34
08fe100d	35	pr_debug("%s(dir=%lu, ino=%d)\n", __func__, dir->i_ino, ino);
1da177e4 LT	36
	37	dir_bh = affs_bread(sb, dir->i_ino);
	38	if (!dir_bh)
	39	return -EIO;
	40
	41	hash_ino = be32_to_cpu(AFFS_HEAD(dir_bh)->table[offset]);
	42	while (hash_ino) {
	43	affs_brelse(dir_bh);
	44	dir_bh = affs_bread(sb, hash_ino);
	45	if (!dir_bh)
	46	return -EIO;
	47	hash_ino = be32_to_cpu(AFFS_TAIL(sb, dir_bh)->hash_chain);
	48	}
	49	AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
	50	AFFS_TAIL(sb, bh)->hash_chain = 0;
	51	affs_fix_checksum(sb, bh);
	52
	53	if (dir->i_ino == dir_bh->b_blocknr)
	54	AFFS_HEAD(dir_bh)->table[offset] = cpu_to_be32(ino);
	55	else
	56	AFFS_TAIL(sb, dir_bh)->hash_chain = cpu_to_be32(ino);
	57
	58	affs_adjust_checksum(dir_bh, ino);
	59	mark_buffer_dirty_inode(dir_bh, dir);
	60	affs_brelse(dir_bh);
	61
02027d42	62	dir->i_mtime = dir->i_ctime = current_time(dir);
1da177e4 LT	63	dir->i_version++;
	64	mark_inode_dirty(dir);
	65
	66	return 0;
	67	}
	68
	69	/* Remove a header block from its directory.
	70	* caller must hold AFFS_DIR->i_hash_lock!
	71	*/
	72
	73	int
	74	affs_remove_hash(struct inode dir, struct buffer_head rem_bh)
	75	{
	76	struct super_block *sb;
	77	struct buffer_head *bh;
	78	u32 rem_ino, hash_ino;
	79	__be32 ino;
	80	int offset, retval;
	81
	82	sb = dir->i_sb;
	83	rem_ino = rem_bh->b_blocknr;
	84	offset = affs_hash_name(sb, AFFS_TAIL(sb, rem_bh)->name+1, AFFS_TAIL(sb, rem_bh)->name[0]);
08fe100d GU	85	pr_debug("%s(dir=%lu, ino=%d, hashval=%d)\n", __func__, dir->i_ino,
08fe100d GU	86	rem_ino, offset);
1da177e4 LT	87
	88	bh = affs_bread(sb, dir->i_ino);
	89	if (!bh)
	90	return -EIO;
	91
	92	retval = -ENOENT;
	93	hash_ino = be32_to_cpu(AFFS_HEAD(bh)->table[offset]);
	94	while (hash_ino) {
	95	if (hash_ino == rem_ino) {
	96	ino = AFFS_TAIL(sb, rem_bh)->hash_chain;
	97	if (dir->i_ino == bh->b_blocknr)
	98	AFFS_HEAD(bh)->table[offset] = ino;
	99	else
	100	AFFS_TAIL(sb, bh)->hash_chain = ino;
	101	affs_adjust_checksum(bh, be32_to_cpu(ino) - hash_ino);
	102	mark_buffer_dirty_inode(bh, dir);
	103	AFFS_TAIL(sb, rem_bh)->parent = 0;
	104	retval = 0;
	105	break;
	106	}
	107	affs_brelse(bh);
	108	bh = affs_bread(sb, hash_ino);
	109	if (!bh)
	110	return -EIO;
	111	hash_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->hash_chain);
	112	}
	113
	114	affs_brelse(bh);
	115
02027d42	116	dir->i_mtime = dir->i_ctime = current_time(dir);
1da177e4 LT	117	dir->i_version++;
	118	mark_inode_dirty(dir);
	119
	120	return retval;
	121	}
	122
	123	static void
12447c40	124	affs_fix_dcache(struct inode *inode, u32 entry_ino)
1da177e4	125	{
12447c40	126	struct dentry *dentry;
873feea0	127	spin_lock(&inode->i_lock);
946e51f2	128	hlist_for_each_entry(dentry, &inode->i_dentry, d_u.d_alias) {
1da177e4	129	if (entry_ino == (u32)(long)dentry->d_fsdata) {
12447c40	130	dentry->d_fsdata = (void *)inode->i_ino;
1da177e4 LT	131	break;
1da177e4 LT	132	}
1da177e4	133	}
873feea0	134	spin_unlock(&inode->i_lock);
1da177e4 LT	135	}
	136
	137
	138	/* Remove header from link chain */
	139
	140	static int
	141	affs_remove_link(struct dentry *dentry)
	142	{
2b0143b5	143	struct inode dir, inode = d_inode(dentry);
1da177e4	144	struct super_block *sb = inode->i_sb;
4709187e	145	struct buffer_head bh, link_bh = NULL;
1da177e4 LT	146	u32 link_ino, ino;
	147	int retval;
	148
9606d9aa	149	pr_debug("%s(key=%ld)\n", __func__, inode->i_ino);
1da177e4 LT	150	retval = -EIO;
	151	bh = affs_bread(sb, inode->i_ino);
	152	if (!bh)
	153	goto done;
	154
	155	link_ino = (u32)(long)dentry->d_fsdata;
	156	if (inode->i_ino == link_ino) {
	157	/* we can't remove the head of the link, as its blocknr is still used as ino,
	158	* so we remove the block of the first link instead.
	159	*/
	160	link_ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain);
	161	link_bh = affs_bread(sb, link_ino);
	162	if (!link_bh)
	163	goto done;
	164
210f8559 DH	165	dir = affs_iget(sb, be32_to_cpu(AFFS_TAIL(sb, link_bh)->parent));
	166	if (IS_ERR(dir)) {
	167	retval = PTR_ERR(dir);
1da177e4	168	goto done;
210f8559	169	}
1da177e4 LT	170
1da177e4 LT	171	affs_lock_dir(dir);
12447c40 AV	172	/*
	173	* if there's a dentry for that block, make it
	174	* refer to inode itself.
	175	*/
	176	affs_fix_dcache(inode, link_ino);
1da177e4	177	retval = affs_remove_hash(dir, link_bh);
ec1ab0ab CH	178	if (retval) {
ec1ab0ab CH	179	affs_unlock_dir(dir);
1da177e4	180	goto done;
ec1ab0ab	181	}
1da177e4 LT	182	mark_buffer_dirty_inode(link_bh, inode);
	183
	184	memcpy(AFFS_TAIL(sb, bh)->name, AFFS_TAIL(sb, link_bh)->name, 32);
	185	retval = affs_insert_hash(dir, bh);
ec1ab0ab CH	186	if (retval) {
ec1ab0ab CH	187	affs_unlock_dir(dir);
1da177e4	188	goto done;
ec1ab0ab	189	}
1da177e4 LT	190	mark_buffer_dirty_inode(bh, inode);
	191
	192	affs_unlock_dir(dir);
	193	iput(dir);
	194	} else {
	195	link_bh = affs_bread(sb, link_ino);
	196	if (!link_bh)
	197	goto done;
	198	}
	199
	200	while ((ino = be32_to_cpu(AFFS_TAIL(sb, bh)->link_chain)) != 0) {
	201	if (ino == link_ino) {
	202	__be32 ino2 = AFFS_TAIL(sb, link_bh)->link_chain;
	203	AFFS_TAIL(sb, bh)->link_chain = ino2;
	204	affs_adjust_checksum(bh, be32_to_cpu(ino2) - link_ino);
	205	mark_buffer_dirty_inode(bh, inode);
	206	retval = 0;
	207	/* Fix the link count, if bh is a normal header block without links */
	208	switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
	209	case ST_LINKDIR:
	210	case ST_LINKFILE:
	211	break;
	212	default:
	213	if (!AFFS_TAIL(sb, bh)->link_chain)
bfe86848	214	set_nlink(inode, 1);
1da177e4 LT	215	}
	216	affs_free_block(sb, link_ino);
	217	goto done;
	218	}
	219	affs_brelse(bh);
	220	bh = affs_bread(sb, ino);
	221	if (!bh)
	222	goto done;
	223	}
	224	retval = -ENOENT;
	225	done:
	226	affs_brelse(link_bh);
	227	affs_brelse(bh);
	228	return retval;
	229	}
	230
	231
	232	static int
	233	affs_empty_dir(struct inode *inode)
	234	{
	235	struct super_block *sb = inode->i_sb;
	236	struct buffer_head *bh;
	237	int retval, size;
	238
	239	retval = -EIO;
	240	bh = affs_bread(sb, inode->i_ino);
	241	if (!bh)
	242	goto done;
	243
	244	retval = -ENOTEMPTY;
	245	for (size = AFFS_SB(sb)->s_hashsize - 1; size >= 0; size--)
	246	if (AFFS_HEAD(bh)->table[size])
	247	goto not_empty;
	248	retval = 0;
	249	not_empty:
	250	affs_brelse(bh);
	251	done:
	252	return retval;
	253	}
	254
	255
	256	/* Remove a filesystem object. If the object to be removed has
	257	* links to it, one of the links must be changed to inherit
	258	* the file or directory. As above, any inode will do.
	259	* The buffer will not be freed. If the header is a link, the
	260	* block will be marked as free.
	261	* This function returns a negative error number in case of
	262	* an error, else 0 if the inode is to be deleted or 1 if not.
	263	*/
	264
	265	int
	266	affs_remove_header(struct dentry *dentry)
	267	{
	268	struct super_block *sb;
	269	struct inode inode, dir;
	270	struct buffer_head *bh = NULL;
	271	int retval;
	272
2b0143b5	273	dir = d_inode(dentry->d_parent);
1da177e4 LT	274	sb = dir->i_sb;
	275
	276	retval = -ENOENT;
2b0143b5	277	inode = d_inode(dentry);
1da177e4 LT	278	if (!inode)
	279	goto done;
	280
9606d9aa	281	pr_debug("%s(key=%ld)\n", __func__, inode->i_ino);
1da177e4 LT	282	retval = -EIO;
	283	bh = affs_bread(sb, (u32)(long)dentry->d_fsdata);
	284	if (!bh)
	285	goto done;
	286
	287	affs_lock_link(inode);
	288	affs_lock_dir(dir);
	289	switch (be32_to_cpu(AFFS_TAIL(sb, bh)->stype)) {
	290	case ST_USERDIR:
	291	/* if we ever want to support links to dirs
	292	* i_hash_lock of the inode must only be
	293	* taken after some checks
	294	*/
	295	affs_lock_dir(inode);
	296	retval = affs_empty_dir(inode);
	297	affs_unlock_dir(inode);
	298	if (retval)
	299	goto done_unlock;
	300	break;
	301	default:
	302	break;
	303	}
	304
	305	retval = affs_remove_hash(dir, bh);
	306	if (retval)
	307	goto done_unlock;
	308	mark_buffer_dirty_inode(bh, inode);
	309
	310	affs_unlock_dir(dir);
	311
	312	if (inode->i_nlink > 1)
	313	retval = affs_remove_link(dentry);
	314	else
6d6b77f1	315	clear_nlink(inode);
1da177e4	316	affs_unlock_link(inode);
02027d42	317	inode->i_ctime = current_time(inode);
1da177e4 LT	318	mark_inode_dirty(inode);
	319
	320	done:
	321	affs_brelse(bh);
	322	return retval;
	323
	324	done_unlock:
	325	affs_unlock_dir(dir);
	326	affs_unlock_link(inode);
	327	goto done;
	328	}
	329
	330	/* Checksum a block, do various consistency checks and optionally return
	331	the blocks type number. DATA points to the block. If their pointers
	332	are non-null, PTYPE and STYPE are set to the primary and secondary
	333	block types respectively, *HASHSIZE is set to the size of the hashtable
	334	(which lets us calculate the block size).
	335	Returns non-zero if the block is not consistent. */
	336
	337	u32
	338	affs_checksum_block(struct super_block sb, struct buffer_head bh)
	339	{
	340	__be32 ptr = (__be32 )bh->b_data;
	341	u32 sum;
	342	int bsize;
	343
	344	sum = 0;
	345	for (bsize = sb->s_blocksize / sizeof(__be32); bsize > 0; bsize--)
	346	sum += be32_to_cpu(*ptr++);
	347	return sum;
	348	}
	349
	350	/*
	351	* Calculate the checksum of a disk block and store it
	352	* at the indicated position.
	353	*/
	354
	355	void
	356	affs_fix_checksum(struct super_block sb, struct buffer_head bh)
	357	{
	358	int cnt = sb->s_blocksize / sizeof(__be32);
	359	__be32 ptr = (__be32 )bh->b_data;
	360	u32 checksum;
	361	__be32 *checksumptr;
	362
	363	checksumptr = ptr + 5;
	364	*checksumptr = 0;
	365	for (checksum = 0; cnt > 0; ptr++, cnt--)
	366	checksum += be32_to_cpu(*ptr);
	367	*checksumptr = cpu_to_be32(-checksum);
	368	}
	369
	370	void
c1618208	371	affs_secs_to_datestamp(time64_t secs, struct affs_date *ds)
1da177e4 LT	372	{
	373	u32 days;
	374	u32 minute;
db39c167	375	s32 rem;
1da177e4 LT	376
	377	secs -= sys_tz.tz_minuteswest * 60 + ((8 * 365 + 2) * 24 * 60 * 60);
	378	if (secs < 0)
	379	secs = 0;
db39c167 D	380	days = div_s64_rem(secs, 86400, &rem);
	381	minute = rem / 60;
	382	rem -= minute * 60;
1da177e4 LT	383
	384	ds->days = cpu_to_be32(days);
	385	ds->mins = cpu_to_be32(minute);
db39c167	386	ds->ticks = cpu_to_be32(rem * 50);
1da177e4 LT	387	}
1da177e4 LT	388
a760b03d	389	umode_t
c1618208	390	affs_prot_to_mode(u32 prot)
1da177e4	391	{
a760b03d	392	umode_t mode = 0;
1da177e4 LT	393
1da177e4 LT	394	if (!(prot & FIBF_NOWRITE))
1bafd6f1	395	mode \|= 0200;
1da177e4	396	if (!(prot & FIBF_NOREAD))
1bafd6f1	397	mode \|= 0400;
1da177e4	398	if (!(prot & FIBF_NOEXECUTE))
1bafd6f1	399	mode \|= 0100;
1da177e4	400	if (prot & FIBF_GRP_WRITE)
1bafd6f1	401	mode \|= 0020;
1da177e4	402	if (prot & FIBF_GRP_READ)
1bafd6f1	403	mode \|= 0040;
1da177e4	404	if (prot & FIBF_GRP_EXECUTE)
1bafd6f1	405	mode \|= 0010;
1da177e4	406	if (prot & FIBF_OTR_WRITE)
1bafd6f1	407	mode \|= 0002;
1da177e4	408	if (prot & FIBF_OTR_READ)
1bafd6f1	409	mode \|= 0004;
1da177e4	410	if (prot & FIBF_OTR_EXECUTE)
1bafd6f1	411	mode \|= 0001;
1da177e4 LT	412
	413	return mode;
	414	}
	415
	416	void
c1618208	417	affs_mode_to_prot(struct inode *inode)
1da177e4 LT	418	{
1da177e4 LT	419	u32 prot = AFFS_I(inode)->i_protect;
a760b03d	420	umode_t mode = inode->i_mode;
1da177e4	421
1bafd6f1	422	if (!(mode & 0100))
1da177e4	423	prot \|= FIBF_NOEXECUTE;
1bafd6f1	424	if (!(mode & 0400))
1da177e4	425	prot \|= FIBF_NOREAD;
1bafd6f1	426	if (!(mode & 0200))
1da177e4	427	prot \|= FIBF_NOWRITE;
1bafd6f1	428	if (mode & 0010)
1da177e4	429	prot \|= FIBF_GRP_EXECUTE;
1bafd6f1	430	if (mode & 0040)
1da177e4	431	prot \|= FIBF_GRP_READ;
1bafd6f1	432	if (mode & 0020)
1da177e4	433	prot \|= FIBF_GRP_WRITE;
1bafd6f1	434	if (mode & 0001)
1da177e4	435	prot \|= FIBF_OTR_EXECUTE;
1bafd6f1	436	if (mode & 0004)
1da177e4	437	prot \|= FIBF_OTR_READ;
1bafd6f1	438	if (mode & 0002)
1da177e4 LT	439	prot \|= FIBF_OTR_WRITE;
	440
	441	AFFS_I(inode)->i_protect = prot;
	442	}
	443
	444	void
	445	affs_error(struct super_block sb, const char function, const char *fmt, ...)
	446	{
1ee54b09 FF	447	struct va_format vaf;
1ee54b09 FF	448	va_list args;
1da177e4	449
1ee54b09 FF	450	va_start(args, fmt);
	451	vaf.fmt = fmt;
	452	vaf.va = &args;
	453	pr_crit("error (device %s): %s(): %pV\n", sb->s_id, function, &vaf);
bc98a42c	454	if (!sb_rdonly(sb))
0158de12	455	pr_warn("Remounting filesystem read-only\n");
1da177e4	456	sb->s_flags \|= MS_RDONLY;
1ee54b09	457	va_end(args);
1da177e4 LT	458	}
	459
	460	void
	461	affs_warning(struct super_block sb, const char function, const char *fmt, ...)
	462	{
1ee54b09 FF	463	struct va_format vaf;
1ee54b09 FF	464	va_list args;
1da177e4	465
1ee54b09 FF	466	va_start(args, fmt);
	467	vaf.fmt = fmt;
	468	vaf.va = &args;
	469	pr_warn("(device %s): %s(): %pV\n", sb->s_id, function, &vaf);
1da177e4	470	va_end(args);
1da177e4 LT	471	}
1da177e4 LT	472
8ca57722 FF	473	bool
	474	affs_nofilenametruncate(const struct dentry *dentry)
	475	{
e0b3f595	476	return affs_test_opt(AFFS_SB(dentry->d_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	}