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v3.5.6
 
  1/*
  2 *  linux/fs/adfs/inode.c
  3 *
  4 *  Copyright (C) 1997-1999 Russell King
  5 *
  6 * This program is free software; you can redistribute it and/or modify
  7 * it under the terms of the GNU General Public License version 2 as
  8 * published by the Free Software Foundation.
  9 */
 10#include <linux/buffer_head.h>
 
 11#include <linux/writeback.h>
 12#include "adfs.h"
 13
 14/*
 15 * Lookup/Create a block at offset 'block' into 'inode'.  We currently do
 16 * not support creation of new blocks, so we return -EIO for this case.
 17 */
 18static int
 19adfs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh,
 20	       int create)
 21{
 22	if (!create) {
 23		if (block >= inode->i_blocks)
 24			goto abort_toobig;
 25
 26		block = __adfs_block_map(inode->i_sb, inode->i_ino, block);
 
 27		if (block)
 28			map_bh(bh, inode->i_sb, block);
 29		return 0;
 30	}
 31	/* don't support allocation of blocks yet */
 32	return -EIO;
 33
 34abort_toobig:
 35	return 0;
 36}
 37
 38static int adfs_writepage(struct page *page, struct writeback_control *wbc)
 
 
 
 
 
 
 39{
 40	return block_write_full_page(page, adfs_get_block, wbc);
 41}
 42
 43static int adfs_readpage(struct file *file, struct page *page)
 44{
 45	return block_read_full_page(page, adfs_get_block);
 
 
 
 46}
 47
 48static int adfs_write_begin(struct file *file, struct address_space *mapping,
 49			loff_t pos, unsigned len, unsigned flags,
 50			struct page **pagep, void **fsdata)
 51{
 52	int ret;
 53
 54	*pagep = NULL;
 55	ret = cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
 56				adfs_get_block,
 57				&ADFS_I(mapping->host)->mmu_private);
 58	if (unlikely(ret)) {
 59		loff_t isize = mapping->host->i_size;
 60		if (pos + len > isize)
 61			vmtruncate(mapping->host, isize);
 62	}
 63
 64	return ret;
 65}
 66
 67static sector_t _adfs_bmap(struct address_space *mapping, sector_t block)
 68{
 69	return generic_block_bmap(mapping, block, adfs_get_block);
 70}
 71
 72static const struct address_space_operations adfs_aops = {
 73	.readpage	= adfs_readpage,
 74	.writepage	= adfs_writepage,
 
 
 75	.write_begin	= adfs_write_begin,
 76	.write_end	= generic_write_end,
 77	.bmap		= _adfs_bmap
 
 78};
 79
 80/*
 81 * Convert ADFS attributes and filetype to Linux permission.
 82 */
 83static umode_t
 84adfs_atts2mode(struct super_block *sb, struct inode *inode)
 85{
 86	unsigned int attr = ADFS_I(inode)->attr;
 87	umode_t mode, rmask;
 88	struct adfs_sb_info *asb = ADFS_SB(sb);
 89
 90	if (attr & ADFS_NDA_DIRECTORY) {
 91		mode = S_IRUGO & asb->s_owner_mask;
 92		return S_IFDIR | S_IXUGO | mode;
 93	}
 94
 95	switch (ADFS_I(inode)->filetype) {
 96	case 0xfc0:	/* LinkFS */
 97		return S_IFLNK|S_IRWXUGO;
 98
 99	case 0xfe6:	/* UnixExec */
100		rmask = S_IRUGO | S_IXUGO;
101		break;
102
103	default:
104		rmask = S_IRUGO;
105	}
106
107	mode = S_IFREG;
108
109	if (attr & ADFS_NDA_OWNER_READ)
110		mode |= rmask & asb->s_owner_mask;
111
112	if (attr & ADFS_NDA_OWNER_WRITE)
113		mode |= S_IWUGO & asb->s_owner_mask;
114
115	if (attr & ADFS_NDA_PUBLIC_READ)
116		mode |= rmask & asb->s_other_mask;
117
118	if (attr & ADFS_NDA_PUBLIC_WRITE)
119		mode |= S_IWUGO & asb->s_other_mask;
120	return mode;
121}
122
123/*
124 * Convert Linux permission to ADFS attribute.  We try to do the reverse
125 * of atts2mode, but there is not a 1:1 translation.
126 */
127static int
128adfs_mode2atts(struct super_block *sb, struct inode *inode)
129{
 
130	umode_t mode;
131	int attr;
132	struct adfs_sb_info *asb = ADFS_SB(sb);
133
134	/* FIXME: should we be able to alter a link? */
135	if (S_ISLNK(inode->i_mode))
136		return ADFS_I(inode)->attr;
137
 
138	if (S_ISDIR(inode->i_mode))
139		attr = ADFS_NDA_DIRECTORY;
140	else
141		attr = 0;
142
143	mode = inode->i_mode & asb->s_owner_mask;
 
144	if (mode & S_IRUGO)
145		attr |= ADFS_NDA_OWNER_READ;
146	if (mode & S_IWUGO)
147		attr |= ADFS_NDA_OWNER_WRITE;
148
149	mode = inode->i_mode & asb->s_other_mask;
150	mode &= ~asb->s_owner_mask;
151	if (mode & S_IRUGO)
152		attr |= ADFS_NDA_PUBLIC_READ;
153	if (mode & S_IWUGO)
154		attr |= ADFS_NDA_PUBLIC_WRITE;
155
156	return attr;
157}
158
 
 
159/*
160 * Convert an ADFS time to Unix time.  ADFS has a 40-bit centi-second time
161 * referenced to 1 Jan 1900 (til 2248) so we need to discard 2208988800 seconds
162 * of time to convert from RISC OS epoch to Unix epoch.
163 */
164static void
165adfs_adfs2unix_time(struct timespec *tv, struct inode *inode)
166{
167	unsigned int high, low;
168	/* 01 Jan 1970 00:00:00 (Unix epoch) as nanoseconds since
169	 * 01 Jan 1900 00:00:00 (RISC OS epoch)
170	 */
171	static const s64 nsec_unix_epoch_diff_risc_os_epoch =
172							2208988800000000000LL;
173	s64 nsec;
174
175	if (ADFS_I(inode)->stamped == 0)
176		goto cur_time;
177
178	high = ADFS_I(inode)->loadaddr & 0xFF; /* top 8 bits of timestamp */
179	low  = ADFS_I(inode)->execaddr;    /* bottom 32 bits of timestamp */
180
181	/* convert 40-bit centi-seconds to 32-bit seconds
182	 * going via nanoseconds to retain precision
183	 */
184	nsec = (((s64) high << 32) | (s64) low) * 10000000; /* cs to ns */
185
186	/* Files dated pre  01 Jan 1970 00:00:00. */
187	if (nsec < nsec_unix_epoch_diff_risc_os_epoch)
188		goto too_early;
189
190	/* convert from RISC OS to Unix epoch */
191	nsec -= nsec_unix_epoch_diff_risc_os_epoch;
192
193	*tv = ns_to_timespec(nsec);
194	return;
195
196 cur_time:
197	*tv = CURRENT_TIME;
198	return;
199
200 too_early:
201	tv->tv_sec = tv->tv_nsec = 0;
202	return;
203}
204
205/*
206 * Convert an Unix time to ADFS time.  We only do this if the entry has a
207 * time/date stamp already.
208 */
209static void
210adfs_unix2adfs_time(struct inode *inode, unsigned int secs)
211{
212	unsigned int high, low;
213
214	if (ADFS_I(inode)->stamped) {
215		/* convert 32-bit seconds to 40-bit centi-seconds */
216		low  = (secs & 255) * 100;
217		high = (secs / 256) * 100 + (low >> 8) + 0x336e996a;
218
219		ADFS_I(inode)->loadaddr = (high >> 24) |
220				(ADFS_I(inode)->loadaddr & ~0xff);
221		ADFS_I(inode)->execaddr = (low & 255) | (high << 8);
222	}
 
 
223}
224
225/*
226 * Fill in the inode information from the object information.
227 *
228 * Note that this is an inode-less filesystem, so we can't use the inode
229 * number to reference the metadata on the media.  Instead, we use the
230 * inode number to hold the object ID, which in turn will tell us where
231 * the data is held.  We also save the parent object ID, and with these
232 * two, we can locate the metadata.
233 *
234 * This does mean that we rely on an objects parent remaining the same at
235 * all times - we cannot cope with a cross-directory rename (yet).
236 */
237struct inode *
238adfs_iget(struct super_block *sb, struct object_info *obj)
239{
240	struct inode *inode;
 
241
242	inode = new_inode(sb);
243	if (!inode)
244		goto out;
245
246	inode->i_uid	 = ADFS_SB(sb)->s_uid;
247	inode->i_gid	 = ADFS_SB(sb)->s_gid;
248	inode->i_ino	 = obj->file_id;
249	inode->i_size	 = obj->size;
250	set_nlink(inode, 2);
251	inode->i_blocks	 = (inode->i_size + sb->s_blocksize - 1) >>
252			    sb->s_blocksize_bits;
253
254	/*
255	 * we need to save the parent directory ID so that
256	 * write_inode can update the directory information
257	 * for this file.  This will need special handling
258	 * for cross-directory renames.
259	 */
260	ADFS_I(inode)->parent_id = obj->parent_id;
 
261	ADFS_I(inode)->loadaddr  = obj->loadaddr;
262	ADFS_I(inode)->execaddr  = obj->execaddr;
263	ADFS_I(inode)->attr      = obj->attr;
264	ADFS_I(inode)->filetype  = obj->filetype;
265	ADFS_I(inode)->stamped   = ((obj->loadaddr & 0xfff00000) == 0xfff00000);
266
267	inode->i_mode	 = adfs_atts2mode(sb, inode);
268	adfs_adfs2unix_time(&inode->i_mtime, inode);
269	inode->i_atime = inode->i_mtime;
270	inode->i_ctime = inode->i_mtime;
 
271
272	if (S_ISDIR(inode->i_mode)) {
273		inode->i_op	= &adfs_dir_inode_operations;
274		inode->i_fop	= &adfs_dir_operations;
275	} else if (S_ISREG(inode->i_mode)) {
276		inode->i_op	= &adfs_file_inode_operations;
277		inode->i_fop	= &adfs_file_operations;
278		inode->i_mapping->a_ops = &adfs_aops;
279		ADFS_I(inode)->mmu_private = inode->i_size;
280	}
281
282	insert_inode_hash(inode);
283
284out:
285	return inode;
286}
287
288/*
289 * Validate and convert a changed access mode/time to their ADFS equivalents.
290 * adfs_write_inode will actually write the information back to the directory
291 * later.
292 */
293int
294adfs_notify_change(struct dentry *dentry, struct iattr *attr)
 
295{
296	struct inode *inode = dentry->d_inode;
297	struct super_block *sb = inode->i_sb;
298	unsigned int ia_valid = attr->ia_valid;
299	int error;
300	
301	error = inode_change_ok(inode, attr);
302
303	/*
304	 * we can't change the UID or GID of any file -
305	 * we have a global UID/GID in the superblock
306	 */
307	if ((ia_valid & ATTR_UID && attr->ia_uid != ADFS_SB(sb)->s_uid) ||
308	    (ia_valid & ATTR_GID && attr->ia_gid != ADFS_SB(sb)->s_gid))
309		error = -EPERM;
310
311	if (error)
312		goto out;
313
314	/* XXX: this is missing some actual on-disk truncation.. */
315	if (ia_valid & ATTR_SIZE)
316		truncate_setsize(inode, attr->ia_size);
317
318	if (ia_valid & ATTR_MTIME) {
319		inode->i_mtime = attr->ia_mtime;
320		adfs_unix2adfs_time(inode, attr->ia_mtime.tv_sec);
 
321	}
 
322	/*
323	 * FIXME: should we make these == to i_mtime since we don't
324	 * have the ability to represent them in our filesystem?
325	 */
326	if (ia_valid & ATTR_ATIME)
327		inode->i_atime = attr->ia_atime;
328	if (ia_valid & ATTR_CTIME)
329		inode->i_ctime = attr->ia_ctime;
330	if (ia_valid & ATTR_MODE) {
331		ADFS_I(inode)->attr = adfs_mode2atts(sb, inode);
332		inode->i_mode = adfs_atts2mode(sb, inode);
333	}
334
335	/*
336	 * FIXME: should we be marking this inode dirty even if
337	 * we don't have any metadata to write back?
338	 */
339	if (ia_valid & (ATTR_SIZE | ATTR_MTIME | ATTR_MODE))
340		mark_inode_dirty(inode);
341out:
342	return error;
343}
344
345/*
346 * write an existing inode back to the directory, and therefore the disk.
347 * The adfs-specific inode data has already been updated by
348 * adfs_notify_change()
349 */
350int adfs_write_inode(struct inode *inode, struct writeback_control *wbc)
351{
352	struct super_block *sb = inode->i_sb;
353	struct object_info obj;
354	int ret;
355
356	obj.file_id	= inode->i_ino;
357	obj.name_len	= 0;
358	obj.parent_id	= ADFS_I(inode)->parent_id;
359	obj.loadaddr	= ADFS_I(inode)->loadaddr;
360	obj.execaddr	= ADFS_I(inode)->execaddr;
361	obj.attr	= ADFS_I(inode)->attr;
362	obj.size	= inode->i_size;
363
364	ret = adfs_dir_update(sb, &obj, wbc->sync_mode == WB_SYNC_ALL);
365	return ret;
366}
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  linux/fs/adfs/inode.c
  4 *
  5 *  Copyright (C) 1997-1999 Russell King
 
 
 
 
  6 */
  7#include <linux/buffer_head.h>
  8#include <linux/mpage.h>
  9#include <linux/writeback.h>
 10#include "adfs.h"
 11
 12/*
 13 * Lookup/Create a block at offset 'block' into 'inode'.  We currently do
 14 * not support creation of new blocks, so we return -EIO for this case.
 15 */
 16static int
 17adfs_get_block(struct inode *inode, sector_t block, struct buffer_head *bh,
 18	       int create)
 19{
 20	if (!create) {
 21		if (block >= inode->i_blocks)
 22			goto abort_toobig;
 23
 24		block = __adfs_block_map(inode->i_sb, ADFS_I(inode)->indaddr,
 25					 block);
 26		if (block)
 27			map_bh(bh, inode->i_sb, block);
 28		return 0;
 29	}
 30	/* don't support allocation of blocks yet */
 31	return -EIO;
 32
 33abort_toobig:
 34	return 0;
 35}
 36
 37static int adfs_writepages(struct address_space *mapping,
 38		struct writeback_control *wbc)
 39{
 40	return mpage_writepages(mapping, wbc, adfs_get_block);
 41}
 42
 43static int adfs_read_folio(struct file *file, struct folio *folio)
 44{
 45	return block_read_full_folio(folio, adfs_get_block);
 46}
 47
 48static void adfs_write_failed(struct address_space *mapping, loff_t to)
 49{
 50	struct inode *inode = mapping->host;
 51
 52	if (to > inode->i_size)
 53		truncate_pagecache(inode, inode->i_size);
 54}
 55
 56static int adfs_write_begin(struct file *file, struct address_space *mapping,
 57			loff_t pos, unsigned len,
 58			struct folio **foliop, void **fsdata)
 59{
 60	int ret;
 61
 62	ret = cont_write_begin(file, mapping, pos, len, foliop, fsdata,
 
 63				adfs_get_block,
 64				&ADFS_I(mapping->host)->mmu_private);
 65	if (unlikely(ret))
 66		adfs_write_failed(mapping, pos + len);
 
 
 
 67
 68	return ret;
 69}
 70
 71static sector_t _adfs_bmap(struct address_space *mapping, sector_t block)
 72{
 73	return generic_block_bmap(mapping, block, adfs_get_block);
 74}
 75
 76static const struct address_space_operations adfs_aops = {
 77	.dirty_folio	= block_dirty_folio,
 78	.invalidate_folio = block_invalidate_folio,
 79	.read_folio	= adfs_read_folio,
 80	.writepages	= adfs_writepages,
 81	.write_begin	= adfs_write_begin,
 82	.write_end	= generic_write_end,
 83	.migrate_folio	= buffer_migrate_folio,
 84	.bmap		= _adfs_bmap,
 85};
 86
 87/*
 88 * Convert ADFS attributes and filetype to Linux permission.
 89 */
 90static umode_t
 91adfs_atts2mode(struct super_block *sb, struct inode *inode)
 92{
 93	unsigned int attr = ADFS_I(inode)->attr;
 94	umode_t mode, rmask;
 95	struct adfs_sb_info *asb = ADFS_SB(sb);
 96
 97	if (attr & ADFS_NDA_DIRECTORY) {
 98		mode = S_IRUGO & asb->s_owner_mask;
 99		return S_IFDIR | S_IXUGO | mode;
100	}
101
102	switch (adfs_filetype(ADFS_I(inode)->loadaddr)) {
103	case 0xfc0:	/* LinkFS */
104		return S_IFLNK|S_IRWXUGO;
105
106	case 0xfe6:	/* UnixExec */
107		rmask = S_IRUGO | S_IXUGO;
108		break;
109
110	default:
111		rmask = S_IRUGO;
112	}
113
114	mode = S_IFREG;
115
116	if (attr & ADFS_NDA_OWNER_READ)
117		mode |= rmask & asb->s_owner_mask;
118
119	if (attr & ADFS_NDA_OWNER_WRITE)
120		mode |= S_IWUGO & asb->s_owner_mask;
121
122	if (attr & ADFS_NDA_PUBLIC_READ)
123		mode |= rmask & asb->s_other_mask;
124
125	if (attr & ADFS_NDA_PUBLIC_WRITE)
126		mode |= S_IWUGO & asb->s_other_mask;
127	return mode;
128}
129
130/*
131 * Convert Linux permission to ADFS attribute.  We try to do the reverse
132 * of atts2mode, but there is not a 1:1 translation.
133 */
134static int adfs_mode2atts(struct super_block *sb, struct inode *inode,
135			  umode_t ia_mode)
136{
137	struct adfs_sb_info *asb = ADFS_SB(sb);
138	umode_t mode;
139	int attr;
 
140
141	/* FIXME: should we be able to alter a link? */
142	if (S_ISLNK(inode->i_mode))
143		return ADFS_I(inode)->attr;
144
145	/* Directories do not have read/write permissions on the media */
146	if (S_ISDIR(inode->i_mode))
147		return ADFS_NDA_DIRECTORY;
 
 
148
149	attr = 0;
150	mode = ia_mode & asb->s_owner_mask;
151	if (mode & S_IRUGO)
152		attr |= ADFS_NDA_OWNER_READ;
153	if (mode & S_IWUGO)
154		attr |= ADFS_NDA_OWNER_WRITE;
155
156	mode = ia_mode & asb->s_other_mask;
157	mode &= ~asb->s_owner_mask;
158	if (mode & S_IRUGO)
159		attr |= ADFS_NDA_PUBLIC_READ;
160	if (mode & S_IWUGO)
161		attr |= ADFS_NDA_PUBLIC_WRITE;
162
163	return attr;
164}
165
166static const s64 nsec_unix_epoch_diff_risc_os_epoch = 2208988800000000000LL;
167
168/*
169 * Convert an ADFS time to Unix time.  ADFS has a 40-bit centi-second time
170 * referenced to 1 Jan 1900 (til 2248) so we need to discard 2208988800 seconds
171 * of time to convert from RISC OS epoch to Unix epoch.
172 */
173static void
174adfs_adfs2unix_time(struct timespec64 *tv, struct inode *inode)
175{
176	unsigned int high, low;
177	/* 01 Jan 1970 00:00:00 (Unix epoch) as nanoseconds since
178	 * 01 Jan 1900 00:00:00 (RISC OS epoch)
179	 */
 
 
180	s64 nsec;
181
182	if (!adfs_inode_is_stamped(inode))
183		goto cur_time;
184
185	high = ADFS_I(inode)->loadaddr & 0xFF; /* top 8 bits of timestamp */
186	low  = ADFS_I(inode)->execaddr;    /* bottom 32 bits of timestamp */
187
188	/* convert 40-bit centi-seconds to 32-bit seconds
189	 * going via nanoseconds to retain precision
190	 */
191	nsec = (((s64) high << 32) | (s64) low) * 10000000; /* cs to ns */
192
193	/* Files dated pre  01 Jan 1970 00:00:00. */
194	if (nsec < nsec_unix_epoch_diff_risc_os_epoch)
195		goto too_early;
196
197	/* convert from RISC OS to Unix epoch */
198	nsec -= nsec_unix_epoch_diff_risc_os_epoch;
199
200	*tv = ns_to_timespec64(nsec);
201	return;
202
203 cur_time:
204	*tv = current_time(inode);
205	return;
206
207 too_early:
208	tv->tv_sec = tv->tv_nsec = 0;
209	return;
210}
211
212/* Convert an Unix time to ADFS time for an entry that is already stamped. */
213static void adfs_unix2adfs_time(struct inode *inode,
214				const struct timespec64 *ts)
 
 
 
215{
216	s64 cs, nsec = timespec64_to_ns(ts);
217
218	/* convert from Unix to RISC OS epoch */
219	nsec += nsec_unix_epoch_diff_risc_os_epoch;
220
221	/* convert from nanoseconds to centiseconds */
222	cs = div_s64(nsec, 10000000);
223
224	cs = clamp_t(s64, cs, 0, 0xffffffffff);
225
226	ADFS_I(inode)->loadaddr &= ~0xff;
227	ADFS_I(inode)->loadaddr |= (cs >> 32) & 0xff;
228	ADFS_I(inode)->execaddr = cs;
229}
230
231/*
232 * Fill in the inode information from the object information.
233 *
234 * Note that this is an inode-less filesystem, so we can't use the inode
235 * number to reference the metadata on the media.  Instead, we use the
236 * inode number to hold the object ID, which in turn will tell us where
237 * the data is held.  We also save the parent object ID, and with these
238 * two, we can locate the metadata.
239 *
240 * This does mean that we rely on an objects parent remaining the same at
241 * all times - we cannot cope with a cross-directory rename (yet).
242 */
243struct inode *
244adfs_iget(struct super_block *sb, struct object_info *obj)
245{
246	struct inode *inode;
247	struct timespec64 ts;
248
249	inode = new_inode(sb);
250	if (!inode)
251		goto out;
252
253	inode->i_uid	 = ADFS_SB(sb)->s_uid;
254	inode->i_gid	 = ADFS_SB(sb)->s_gid;
255	inode->i_ino	 = obj->indaddr;
256	inode->i_size	 = obj->size;
257	set_nlink(inode, 2);
258	inode->i_blocks	 = (inode->i_size + sb->s_blocksize - 1) >>
259			    sb->s_blocksize_bits;
260
261	/*
262	 * we need to save the parent directory ID so that
263	 * write_inode can update the directory information
264	 * for this file.  This will need special handling
265	 * for cross-directory renames.
266	 */
267	ADFS_I(inode)->parent_id = obj->parent_id;
268	ADFS_I(inode)->indaddr   = obj->indaddr;
269	ADFS_I(inode)->loadaddr  = obj->loadaddr;
270	ADFS_I(inode)->execaddr  = obj->execaddr;
271	ADFS_I(inode)->attr      = obj->attr;
 
 
272
273	inode->i_mode	 = adfs_atts2mode(sb, inode);
274	adfs_adfs2unix_time(&ts, inode);
275	inode_set_atime_to_ts(inode, ts);
276	inode_set_mtime_to_ts(inode, ts);
277	inode_set_ctime_to_ts(inode, ts);
278
279	if (S_ISDIR(inode->i_mode)) {
280		inode->i_op	= &adfs_dir_inode_operations;
281		inode->i_fop	= &adfs_dir_operations;
282	} else if (S_ISREG(inode->i_mode)) {
283		inode->i_op	= &adfs_file_inode_operations;
284		inode->i_fop	= &adfs_file_operations;
285		inode->i_mapping->a_ops = &adfs_aops;
286		ADFS_I(inode)->mmu_private = inode->i_size;
287	}
288
289	inode_fake_hash(inode);
290
291out:
292	return inode;
293}
294
295/*
296 * Validate and convert a changed access mode/time to their ADFS equivalents.
297 * adfs_write_inode will actually write the information back to the directory
298 * later.
299 */
300int
301adfs_notify_change(struct mnt_idmap *idmap, struct dentry *dentry,
302		   struct iattr *attr)
303{
304	struct inode *inode = d_inode(dentry);
305	struct super_block *sb = inode->i_sb;
306	unsigned int ia_valid = attr->ia_valid;
307	int error;
308	
309	error = setattr_prepare(&nop_mnt_idmap, dentry, attr);
310
311	/*
312	 * we can't change the UID or GID of any file -
313	 * we have a global UID/GID in the superblock
314	 */
315	if ((ia_valid & ATTR_UID && !uid_eq(attr->ia_uid, ADFS_SB(sb)->s_uid)) ||
316	    (ia_valid & ATTR_GID && !gid_eq(attr->ia_gid, ADFS_SB(sb)->s_gid)))
317		error = -EPERM;
318
319	if (error)
320		goto out;
321
322	/* XXX: this is missing some actual on-disk truncation.. */
323	if (ia_valid & ATTR_SIZE)
324		truncate_setsize(inode, attr->ia_size);
325
326	if (ia_valid & ATTR_MTIME && adfs_inode_is_stamped(inode)) {
327		adfs_unix2adfs_time(inode, &attr->ia_mtime);
328		adfs_adfs2unix_time(&attr->ia_mtime, inode);
329		inode_set_mtime_to_ts(inode, attr->ia_mtime);
330	}
331
332	/*
333	 * FIXME: should we make these == to i_mtime since we don't
334	 * have the ability to represent them in our filesystem?
335	 */
336	if (ia_valid & ATTR_ATIME)
337		inode_set_atime_to_ts(inode, attr->ia_atime);
338	if (ia_valid & ATTR_CTIME)
339		inode_set_ctime_to_ts(inode, attr->ia_ctime);
340	if (ia_valid & ATTR_MODE) {
341		ADFS_I(inode)->attr = adfs_mode2atts(sb, inode, attr->ia_mode);
342		inode->i_mode = adfs_atts2mode(sb, inode);
343	}
344
345	/*
346	 * FIXME: should we be marking this inode dirty even if
347	 * we don't have any metadata to write back?
348	 */
349	if (ia_valid & (ATTR_SIZE | ATTR_MTIME | ATTR_MODE))
350		mark_inode_dirty(inode);
351out:
352	return error;
353}
354
355/*
356 * write an existing inode back to the directory, and therefore the disk.
357 * The adfs-specific inode data has already been updated by
358 * adfs_notify_change()
359 */
360int adfs_write_inode(struct inode *inode, struct writeback_control *wbc)
361{
362	struct super_block *sb = inode->i_sb;
363	struct object_info obj;
 
364
365	obj.indaddr	= ADFS_I(inode)->indaddr;
366	obj.name_len	= 0;
367	obj.parent_id	= ADFS_I(inode)->parent_id;
368	obj.loadaddr	= ADFS_I(inode)->loadaddr;
369	obj.execaddr	= ADFS_I(inode)->execaddr;
370	obj.attr	= ADFS_I(inode)->attr;
371	obj.size	= inode->i_size;
372
373	return adfs_dir_update(sb, &obj, wbc->sync_mode == WB_SYNC_ALL);
 
374}