[mirror_ubuntu-jammy-kernel.git] / fs / adfs / inode.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  linux/fs/adfs/inode.c
 *
 *  Copyright (C) 1997-1999 Russell King
 */
#include <linux/buffer_head.h>
#include <linux/writeback.h>
#include "adfs.h"

/*
 * Lookup/Create a block at offset 'block' into 'inode'.  We currently do
 * not support creation of new blocks, so we return -EIO for this case.
 */
static int
adfs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh,
	       int create)
{
	if (!create) {
		if (block >= inode->i_blocks)
			goto abort_toobig;

		block = __adfs_block_map(inode->i_sb, inode->i_ino, block);
		if (block)
			map_bh(bh, inode->i_sb, block);
		return 0;
	}
	/* don't support allocation of blocks yet */
	return -EIO;

abort_toobig:
	return 0;
}

static int adfs_writepage(struct page *page, struct writeback_control *wbc)
{
	return block_write_full_page(page, adfs_get_block, wbc);
}

static int adfs_readpage(struct file *file, struct page *page)
{
	return block_read_full_page(page, adfs_get_block);
}

static void adfs_write_failed(struct address_space *mapping, loff_t to)
{
	struct inode *inode = mapping->host;

	if (to > inode->i_size)
		truncate_pagecache(inode, inode->i_size);
}

static int adfs_write_begin(struct file *file, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned flags,
			struct page **pagep, void **fsdata)
{
	int ret;

	*pagep = NULL;
	ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
				adfs_get_block,
				&ADFS_I(mapping->host)->mmu_private);
	if (unlikely(ret))
		adfs_write_failed(mapping, pos + len);

	return ret;
}

static sector_t _adfs_bmap(struct address_space *mapping, sector_t block)
{
	return generic_block_bmap(mapping, block, adfs_get_block);
}

static const struct address_space_operations adfs_aops = {
	.readpage	= adfs_readpage,
	.writepage	= adfs_writepage,
	.write_begin	= adfs_write_begin,
	.write_end	= generic_write_end,
	.bmap		= _adfs_bmap
};

/*
 * Convert ADFS attributes and filetype to Linux permission.
 */
static umode_t
adfs_atts2mode(struct super_block *sb, struct inode *inode)
{
	unsigned int attr = ADFS_I(inode)->attr;
	umode_t mode, rmask;
	struct adfs_sb_info *asb = ADFS_SB(sb);

	if (attr & ADFS_NDA_DIRECTORY) {
		mode = S_IRUGO & asb->s_owner_mask;
		return S_IFDIR | S_IXUGO | mode;
	}

	switch (ADFS_I(inode)->filetype) {
	case 0xfc0:	/* LinkFS */
		return S_IFLNK|S_IRWXUGO;

	case 0xfe6:	/* UnixExec */
		rmask = S_IRUGO | S_IXUGO;
		break;

	default:
		rmask = S_IRUGO;
	}

	mode = S_IFREG;

	if (attr & ADFS_NDA_OWNER_READ)
		mode |= rmask & asb->s_owner_mask;

	if (attr & ADFS_NDA_OWNER_WRITE)
		mode |= S_IWUGO & asb->s_owner_mask;

	if (attr & ADFS_NDA_PUBLIC_READ)
		mode |= rmask & asb->s_other_mask;

	if (attr & ADFS_NDA_PUBLIC_WRITE)
		mode |= S_IWUGO & asb->s_other_mask;
	return mode;
}

/*
 * Convert Linux permission to ADFS attribute.  We try to do the reverse
 * of atts2mode, but there is not a 1:1 translation.
 */
static int
adfs_mode2atts(struct super_block *sb, struct inode *inode)
{
	umode_t mode;
	int attr;
	struct adfs_sb_info *asb = ADFS_SB(sb);

	/* FIXME: should we be able to alter a link? */
	if (S_ISLNK(inode->i_mode))
		return ADFS_I(inode)->attr;

	if (S_ISDIR(inode->i_mode))
		attr = ADFS_NDA_DIRECTORY;
	else
		attr = 0;

	mode = inode->i_mode & asb->s_owner_mask;
	if (mode & S_IRUGO)
		attr |= ADFS_NDA_OWNER_READ;
	if (mode & S_IWUGO)
		attr |= ADFS_NDA_OWNER_WRITE;

	mode = inode->i_mode & asb->s_other_mask;
	mode &= ~asb->s_owner_mask;
	if (mode & S_IRUGO)
		attr |= ADFS_NDA_PUBLIC_READ;
	if (mode & S_IWUGO)
		attr |= ADFS_NDA_PUBLIC_WRITE;

	return attr;
}

/*
 * Convert an ADFS time to Unix time.  ADFS has a 40-bit centi-second time
 * referenced to 1 Jan 1900 (til 2248) so we need to discard 2208988800 seconds
 * of time to convert from RISC OS epoch to Unix epoch.
 */
static void
adfs_adfs2unix_time(struct timespec64 *tv, struct inode *inode)
{
	unsigned int high, low;
	/* 01 Jan 1970 00:00:00 (Unix epoch) as nanoseconds since
	 * 01 Jan 1900 00:00:00 (RISC OS epoch)
	 */
	static const s64 nsec_unix_epoch_diff_risc_os_epoch =
							2208988800000000000LL;
	s64 nsec;

	if (ADFS_I(inode)->stamped == 0)
		goto cur_time;

	high = ADFS_I(inode)->loadaddr & 0xFF; /* top 8 bits of timestamp */
	low  = ADFS_I(inode)->execaddr;    /* bottom 32 bits of timestamp */

	/* convert 40-bit centi-seconds to 32-bit seconds
	 * going via nanoseconds to retain precision
	 */
	nsec = (((s64) high << 32) | (s64) low) * 10000000; /* cs to ns */

	/* Files dated pre  01 Jan 1970 00:00:00. */
	if (nsec < nsec_unix_epoch_diff_risc_os_epoch)
		goto too_early;

	/* convert from RISC OS to Unix epoch */
	nsec -= nsec_unix_epoch_diff_risc_os_epoch;

	*tv = ns_to_timespec64(nsec);
	return;

 cur_time:
	*tv = current_time(inode);
	return;

 too_early:
	tv->tv_sec = tv->tv_nsec = 0;
	return;
}

/*
 * Convert an Unix time to ADFS time.  We only do this if the entry has a
 * time/date stamp already.
 */
static void
adfs_unix2adfs_time(struct inode *inode, unsigned int secs)
{
	unsigned int high, low;

	if (ADFS_I(inode)->stamped) {
		/* convert 32-bit seconds to 40-bit centi-seconds */
		low  = (secs & 255) * 100;
		high = (secs / 256) * 100 + (low >> 8) + 0x336e996a;

		ADFS_I(inode)->loadaddr = (high >> 24) |
				(ADFS_I(inode)->loadaddr & ~0xff);
		ADFS_I(inode)->execaddr = (low & 255) | (high << 8);
	}
}

/*
 * Fill in the inode information from the object information.
 *
 * Note that this is an inode-less filesystem, so we can't use the inode
 * number to reference the metadata on the media.  Instead, we use the
 * inode number to hold the object ID, which in turn will tell us where
 * the data is held.  We also save the parent object ID, and with these
 * two, we can locate the metadata.
 *
 * This does mean that we rely on an objects parent remaining the same at
 * all times - we cannot cope with a cross-directory rename (yet).
 */
struct inode *
adfs_iget(struct super_block *sb, struct object_info *obj)
{
	struct inode *inode;

	inode = new_inode(sb);
	if (!inode)
		goto out;

	inode->i_uid	 = ADFS_SB(sb)->s_uid;
	inode->i_gid	 = ADFS_SB(sb)->s_gid;
	inode->i_ino	 = obj->file_id;
	inode->i_size	 = obj->size;
	set_nlink(inode, 2);
	inode->i_blocks	 = (inode->i_size + sb->s_blocksize - 1) >>
			    sb->s_blocksize_bits;

	/*
	 * we need to save the parent directory ID so that
	 * write_inode can update the directory information
	 * for this file.  This will need special handling
	 * for cross-directory renames.
	 */
	ADFS_I(inode)->parent_id = obj->parent_id;
	ADFS_I(inode)->loadaddr  = obj->loadaddr;
	ADFS_I(inode)->execaddr  = obj->execaddr;
	ADFS_I(inode)->attr      = obj->attr;
	ADFS_I(inode)->filetype  = obj->filetype;
	ADFS_I(inode)->stamped   = ((obj->loadaddr & 0xfff00000) == 0xfff00000);

	inode->i_mode	 = adfs_atts2mode(sb, inode);
	adfs_adfs2unix_time(&inode->i_mtime, inode);
	inode->i_atime = inode->i_mtime;
	inode->i_ctime = inode->i_mtime;

	if (S_ISDIR(inode->i_mode)) {
		inode->i_op	= &adfs_dir_inode_operations;
		inode->i_fop	= &adfs_dir_operations;
	} else if (S_ISREG(inode->i_mode)) {
		inode->i_op	= &adfs_file_inode_operations;
		inode->i_fop	= &adfs_file_operations;
		inode->i_mapping->a_ops = &adfs_aops;
		ADFS_I(inode)->mmu_private = inode->i_size;
	}

	inode_fake_hash(inode);

out:
	return inode;
}

/*
 * Validate and convert a changed access mode/time to their ADFS equivalents.
 * adfs_write_inode will actually write the information back to the directory
 * later.
 */
int
adfs_notify_change(struct dentry *dentry, struct iattr *attr)
{
	struct inode *inode = d_inode(dentry);
	struct super_block *sb = inode->i_sb;
	unsigned int ia_valid = attr->ia_valid;
	int error;
	
	error = setattr_prepare(dentry, attr);

	/*
	 * we can't change the UID or GID of any file -
	 * we have a global UID/GID in the superblock
	 */
	if ((ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, ADFS_SB(sb)->s_uid)) ||
	    (ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, ADFS_SB(sb)->s_gid)))
		error = -EPERM;

	if (error)
		goto out;

	/* XXX: this is missing some actual on-disk truncation.. */
	if (ia_valid & ATTR_SIZE)
		truncate_setsize(inode, attr->ia_size);

	if (ia_valid & ATTR_MTIME) {
		inode->i_mtime = attr->ia_mtime;
		adfs_unix2adfs_time(inode, attr->ia_mtime.tv_sec);
	}
	/*
	 * FIXME: should we make these == to i_mtime since we don't
	 * have the ability to represent them in our filesystem?
	 */
	if (ia_valid & ATTR_ATIME)
		inode->i_atime = attr->ia_atime;
	if (ia_valid & ATTR_CTIME)
		inode->i_ctime = attr->ia_ctime;
	if (ia_valid & ATTR_MODE) {
		ADFS_I(inode)->attr = adfs_mode2atts(sb, inode);
		inode->i_mode = adfs_atts2mode(sb, inode);
	}

	/*
	 * FIXME: should we be marking this inode dirty even if
	 * we don't have any metadata to write back?
	 */
	if (ia_valid & (ATTR_SIZE | ATTR_MTIME | ATTR_MODE))
		mark_inode_dirty(inode);
out:
	return error;
}

/*
 * write an existing inode back to the directory, and therefore the disk.
 * The adfs-specific inode data has already been updated by
 * adfs_notify_change()
 */
int adfs_write_inode(struct inode *inode, struct writeback_control *wbc)
{
	struct super_block *sb = inode->i_sb;
	struct object_info obj;
	int ret;

	obj.file_id	= inode->i_ino;
	obj.name_len	= 0;
	obj.parent_id	= ADFS_I(inode)->parent_id;
	obj.loadaddr	= ADFS_I(inode)->loadaddr;
	obj.execaddr	= ADFS_I(inode)->execaddr;
	obj.attr	= ADFS_I(inode)->attr;
	obj.size	= inode->i_size;

	ret = adfs_dir_update(sb, &obj, wbc->sync_mode == WB_SYNC_ALL);
	return ret;
}
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
1da177e4 LT	2	/*
	3	* linux/fs/adfs/inode.c
	4	*
	5	* Copyright (C) 1997-1999 Russell King
1da177e4	6	*/
1da177e4	7	#include <linux/buffer_head.h>
a9185b41	8	#include <linux/writeback.h>
1da177e4 LT	9	#include "adfs.h"
	10
	11	/*
	12	* Lookup/Create a block at offset 'block' into 'inode'. We currently do
	13	* not support creation of new blocks, so we return -EIO for this case.
	14	*/
	15	static int
	16	adfs_get_block(struct inode inode, sector_t block, struct buffer_head bh,
	17	int create)
	18	{
1da177e4 LT	19	if (!create) {
	20	if (block >= inode->i_blocks)
	21	goto abort_toobig;
	22
	23	block = __adfs_block_map(inode->i_sb, inode->i_ino, block);
	24	if (block)
	25	map_bh(bh, inode->i_sb, block);
	26	return 0;
	27	}
	28	/* don't support allocation of blocks yet */
	29	return -EIO;
	30
1da177e4 LT	31	abort_toobig:
	32	return 0;
	33	}
	34
	35	static int adfs_writepage(struct page page, struct writeback_control wbc)
	36	{
	37	return block_write_full_page(page, adfs_get_block, wbc);
	38	}
	39
	40	static int adfs_readpage(struct file file, struct page page)
	41	{
	42	return block_read_full_page(page, adfs_get_block);
	43	}
	44
62295183 MS	45	static void adfs_write_failed(struct address_space *mapping, loff_t to)
	46	{
	47	struct inode *inode = mapping->host;
	48
	49	if (to > inode->i_size)
7caef267	50	truncate_pagecache(inode, inode->i_size);
62295183 MS	51	}
62295183 MS	52
b4585729 NP	53	static int adfs_write_begin(struct file file, struct address_space mapping,
	54	loff_t pos, unsigned len, unsigned flags,
	55	struct page pagep, void fsdata)
1da177e4	56	{
282dc178 CH	57	int ret;
282dc178 CH	58
b4585729	59	*pagep = NULL;
282dc178	60	ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
b4585729 NP	61	adfs_get_block,
b4585729 NP	62	&ADFS_I(mapping->host)->mmu_private);
62295183 MS	63	if (unlikely(ret))
62295183 MS	64	adfs_write_failed(mapping, pos + len);
282dc178 CH	65
282dc178 CH	66	return ret;
1da177e4 LT	67	}
	68
	69	static sector_t _adfs_bmap(struct address_space *mapping, sector_t block)
	70	{
	71	return generic_block_bmap(mapping, block, adfs_get_block);
	72	}
	73
f5e54d6e	74	static const struct address_space_operations adfs_aops = {
1da177e4 LT	75	.readpage = adfs_readpage,
1da177e4 LT	76	.writepage = adfs_writepage,
b4585729 NP	77	.write_begin = adfs_write_begin,
b4585729 NP	78	.write_end = generic_write_end,
1da177e4 LT	79	.bmap = _adfs_bmap
	80	};
	81
1da177e4 LT	82	/*
	83	* Convert ADFS attributes and filetype to Linux permission.
	84	*/
	85	static umode_t
	86	adfs_atts2mode(struct super_block sb, struct inode inode)
	87	{
da23ef05	88	unsigned int attr = ADFS_I(inode)->attr;
1da177e4 LT	89	umode_t mode, rmask;
	90	struct adfs_sb_info *asb = ADFS_SB(sb);
	91
	92	if (attr & ADFS_NDA_DIRECTORY) {
	93	mode = S_IRUGO & asb->s_owner_mask;
	94	return S_IFDIR \| S_IXUGO \| mode;
	95	}
	96
da23ef05	97	switch (ADFS_I(inode)->filetype) {
1da177e4 LT	98	case 0xfc0: /* LinkFS */
	99	return S_IFLNK\|S_IRWXUGO;
	100
	101	case 0xfe6: /* UnixExec */
	102	rmask = S_IRUGO \| S_IXUGO;
	103	break;
	104
	105	default:
	106	rmask = S_IRUGO;
	107	}
	108
	109	mode = S_IFREG;
	110
	111	if (attr & ADFS_NDA_OWNER_READ)
	112	mode \|= rmask & asb->s_owner_mask;
	113
	114	if (attr & ADFS_NDA_OWNER_WRITE)
	115	mode \|= S_IWUGO & asb->s_owner_mask;
	116
	117	if (attr & ADFS_NDA_PUBLIC_READ)
	118	mode \|= rmask & asb->s_other_mask;
	119
	120	if (attr & ADFS_NDA_PUBLIC_WRITE)
	121	mode \|= S_IWUGO & asb->s_other_mask;
	122	return mode;
	123	}
	124
	125	/*
	126	* Convert Linux permission to ADFS attribute. We try to do the reverse
	127	* of atts2mode, but there is not a 1:1 translation.
	128	*/
	129	static int
	130	adfs_mode2atts(struct super_block sb, struct inode inode)
	131	{
	132	umode_t mode;
	133	int attr;
	134	struct adfs_sb_info *asb = ADFS_SB(sb);
	135
	136	/* FIXME: should we be able to alter a link? */
	137	if (S_ISLNK(inode->i_mode))
	138	return ADFS_I(inode)->attr;
	139
	140	if (S_ISDIR(inode->i_mode))
	141	attr = ADFS_NDA_DIRECTORY;
	142	else
	143	attr = 0;
	144
	145	mode = inode->i_mode & asb->s_owner_mask;
	146	if (mode & S_IRUGO)
	147	attr \|= ADFS_NDA_OWNER_READ;
	148	if (mode & S_IWUGO)
	149	attr \|= ADFS_NDA_OWNER_WRITE;
	150
	151	mode = inode->i_mode & asb->s_other_mask;
	152	mode &= ~asb->s_owner_mask;
	153	if (mode & S_IRUGO)
	154	attr \|= ADFS_NDA_PUBLIC_READ;
	155	if (mode & S_IWUGO)
	156	attr \|= ADFS_NDA_PUBLIC_WRITE;
	157
	158	return attr;
	159	}
	160
	161	/*
162	* Convert an ADFS time to Unix time. ADFS has a 40-bit centi-second time
7a9730af SS	163	* referenced to 1 Jan 1900 (til 2248) so we need to discard 2208988800 seconds
7a9730af SS	164	* of time to convert from RISC OS epoch to Unix epoch.
1da177e4 LT	165	*/
1da177e4 LT	166	static void
d9edcbc4	167	adfs_adfs2unix_time(struct timespec64 tv, struct inode inode)
1da177e4 LT	168	{
1da177e4 LT	169	unsigned int high, low;
7a9730af SS	170	/* 01 Jan 1970 00:00:00 (Unix epoch) as nanoseconds since
	171	* 01 Jan 1900 00:00:00 (RISC OS epoch)
	172	*/
	173	static const s64 nsec_unix_epoch_diff_risc_os_epoch =
	174	2208988800000000000LL;
	175	s64 nsec;
1da177e4 LT	176
	177	if (ADFS_I(inode)->stamped == 0)
	178	goto cur_time;
	179
7a9730af SS	180	high = ADFS_I(inode)->loadaddr & 0xFF; /* top 8 bits of timestamp */
7a9730af SS	181	low = ADFS_I(inode)->execaddr; /* bottom 32 bits of timestamp */
1da177e4	182
7a9730af SS	183	/* convert 40-bit centi-seconds to 32-bit seconds
	184	* going via nanoseconds to retain precision
	185	*/
	186	nsec = (((s64) high << 32) \| (s64) low) * 10000000; /* cs to ns */
1da177e4 LT	187
1da177e4 LT	188	/* Files dated pre 01 Jan 1970 00:00:00. */
7a9730af	189	if (nsec < nsec_unix_epoch_diff_risc_os_epoch)
1da177e4 LT	190	goto too_early;
1da177e4 LT	191
7a9730af SS	192	/* convert from RISC OS to Unix epoch */
7a9730af SS	193	nsec -= nsec_unix_epoch_diff_risc_os_epoch;
1da177e4	194
d9edcbc4	195	*tv = ns_to_timespec64(nsec);
1da177e4 LT	196	return;
	197
	198	cur_time:
d9edcbc4	199	*tv = current_time(inode);
1da177e4 LT	200	return;
	201
	202	too_early:
	203	tv->tv_sec = tv->tv_nsec = 0;
	204	return;
1da177e4 LT	205	}
	206
	207	/*
	208	* Convert an Unix time to ADFS time. We only do this if the entry has a
	209	* time/date stamp already.
	210	*/
	211	static void
	212	adfs_unix2adfs_time(struct inode *inode, unsigned int secs)
	213	{
	214	unsigned int high, low;
	215
	216	if (ADFS_I(inode)->stamped) {
	217	/* convert 32-bit seconds to 40-bit centi-seconds */
	218	low = (secs & 255) * 100;
	219	high = (secs / 256) * 100 + (low >> 8) + 0x336e996a;
	220
	221	ADFS_I(inode)->loadaddr = (high >> 24) \|
	222	(ADFS_I(inode)->loadaddr & ~0xff);
	223	ADFS_I(inode)->execaddr = (low & 255) \| (high << 8);
	224	}
	225	}
	226
	227	/*
	228	* Fill in the inode information from the object information.
	229	*
	230	* Note that this is an inode-less filesystem, so we can't use the inode
	231	* number to reference the metadata on the media. Instead, we use the
	232	* inode number to hold the object ID, which in turn will tell us where
	233	* the data is held. We also save the parent object ID, and with these
	234	* two, we can locate the metadata.
	235	*
	236	* This does mean that we rely on an objects parent remaining the same at
	237	* all times - we cannot cope with a cross-directory rename (yet).
	238	*/
	239	struct inode *
	240	adfs_iget(struct super_block sb, struct object_info obj)
	241	{
	242	struct inode *inode;
	243
	244	inode = new_inode(sb);
	245	if (!inode)
	246	goto out;
	247
	248	inode->i_uid = ADFS_SB(sb)->s_uid;
	249	inode->i_gid = ADFS_SB(sb)->s_gid;
	250	inode->i_ino = obj->file_id;
	251	inode->i_size = obj->size;
bfe86848	252	set_nlink(inode, 2);
1da177e4 LT	253	inode->i_blocks = (inode->i_size + sb->s_blocksize - 1) >>
	254	sb->s_blocksize_bits;
	255
	256	/*
	257	* we need to save the parent directory ID so that
	258	* write_inode can update the directory information
	259	* for this file. This will need special handling
	260	* for cross-directory renames.
	261	*/
	262	ADFS_I(inode)->parent_id = obj->parent_id;
	263	ADFS_I(inode)->loadaddr = obj->loadaddr;
	264	ADFS_I(inode)->execaddr = obj->execaddr;
	265	ADFS_I(inode)->attr = obj->attr;
da23ef05 SS	266	ADFS_I(inode)->filetype = obj->filetype;
da23ef05 SS	267	ADFS_I(inode)->stamped = ((obj->loadaddr & 0xfff00000) == 0xfff00000);
1da177e4 LT	268
1da177e4 LT	269	inode->i_mode = adfs_atts2mode(sb, inode);
d9edcbc4	270	adfs_adfs2unix_time(&inode->i_mtime, inode);
1da177e4 LT	271	inode->i_atime = inode->i_mtime;
	272	inode->i_ctime = inode->i_mtime;
	273
	274	if (S_ISDIR(inode->i_mode)) {
	275	inode->i_op = &adfs_dir_inode_operations;
	276	inode->i_fop = &adfs_dir_operations;
	277	} else if (S_ISREG(inode->i_mode)) {
	278	inode->i_op = &adfs_file_inode_operations;
	279	inode->i_fop = &adfs_file_operations;
	280	inode->i_mapping->a_ops = &adfs_aops;
	281	ADFS_I(inode)->mmu_private = inode->i_size;
	282	}
	283
d8e78da8	284	inode_fake_hash(inode);
1da177e4 LT	285
	286	out:
	287	return inode;
	288	}
	289
	290	/*
	291	* Validate and convert a changed access mode/time to their ADFS equivalents.
	292	* adfs_write_inode will actually write the information back to the directory
	293	* later.
	294	*/
	295	int
	296	adfs_notify_change(struct dentry dentry, struct iattr attr)
	297	{
2b0143b5	298	struct inode *inode = d_inode(dentry);
1da177e4 LT	299	struct super_block *sb = inode->i_sb;
	300	unsigned int ia_valid = attr->ia_valid;
	301	int error;
	302
31051c85	303	error = setattr_prepare(dentry, attr);
1da177e4 LT	304
	305	/*
	306	* we can't change the UID or GID of any file -
	307	* we have a global UID/GID in the superblock
	308	*/
c010d1ff EB	309	if ((ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, ADFS_SB(sb)->s_uid)) \|\|
c010d1ff EB	310	(ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, ADFS_SB(sb)->s_gid)))
1da177e4 LT	311	error = -EPERM;
	312
	313	if (error)
	314	goto out;
	315
15c6fd97	316	/* XXX: this is missing some actual on-disk truncation.. */
1da177e4	317	if (ia_valid & ATTR_SIZE)
2c27c65e	318	truncate_setsize(inode, attr->ia_size);
1da177e4 LT	319
	320	if (ia_valid & ATTR_MTIME) {
	321	inode->i_mtime = attr->ia_mtime;
	322	adfs_unix2adfs_time(inode, attr->ia_mtime.tv_sec);
	323	}
	324	/*
	325	* FIXME: should we make these == to i_mtime since we don't
	326	* have the ability to represent them in our filesystem?
	327	*/
	328	if (ia_valid & ATTR_ATIME)
	329	inode->i_atime = attr->ia_atime;
	330	if (ia_valid & ATTR_CTIME)
	331	inode->i_ctime = attr->ia_ctime;
	332	if (ia_valid & ATTR_MODE) {
	333	ADFS_I(inode)->attr = adfs_mode2atts(sb, inode);
	334	inode->i_mode = adfs_atts2mode(sb, inode);
	335	}
	336
	337	/*
	338	* FIXME: should we be marking this inode dirty even if
	339	* we don't have any metadata to write back?
	340	*/
	341	if (ia_valid & (ATTR_SIZE \| ATTR_MTIME \| ATTR_MODE))
	342	mark_inode_dirty(inode);
	343	out:
1da177e4 LT	344	return error;
	345	}
	346
	347	/*
	348	* write an existing inode back to the directory, and therefore the disk.
	349	* The adfs-specific inode data has already been updated by
	350	* adfs_notify_change()
	351	*/
a9185b41	352	int adfs_write_inode(struct inode inode, struct writeback_control wbc)
1da177e4 LT	353	{
	354	struct super_block *sb = inode->i_sb;
	355	struct object_info obj;
	356	int ret;
	357
1da177e4 LT	358	obj.file_id = inode->i_ino;
	359	obj.name_len = 0;
	360	obj.parent_id = ADFS_I(inode)->parent_id;
	361	obj.loadaddr = ADFS_I(inode)->loadaddr;
	362	obj.execaddr = ADFS_I(inode)->execaddr;
	363	obj.attr = ADFS_I(inode)->attr;
	364	obj.size = inode->i_size;
	365
a9185b41	366	ret = adfs_dir_update(sb, &obj, wbc->sync_mode == WB_SYNC_ALL);
1da177e4 LT	367	return ret;
1da177e4 LT	368	}