[linux-2.6-block.git] / fs / sysv / dir.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  linux/fs/sysv/dir.c
 *
 *  minix/dir.c
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *
 *  coh/dir.c
 *  Copyright (C) 1993  Pascal Haible, Bruno Haible
 *
 *  sysv/dir.c
 *  Copyright (C) 1993  Bruno Haible
 *
 *  SystemV/Coherent directory handling functions
 */

#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/swap.h>
#include "sysv.h"

static int sysv_readdir(struct file *, struct dir_context *);

const struct file_operations sysv_dir_operations = {
	.llseek		= generic_file_llseek,
	.read		= generic_read_dir,
	.iterate_shared	= sysv_readdir,
	.fsync		= generic_file_fsync,
};

static inline void dir_put_page(struct page *page)
{
	kunmap(page);
	put_page(page);
}

static void dir_commit_chunk(struct page *page, loff_t pos, unsigned len)
{
	struct address_space *mapping = page->mapping;
	struct inode *dir = mapping->host;

	block_write_end(NULL, mapping, pos, len, len, page, NULL);
	if (pos+len > dir->i_size) {
		i_size_write(dir, pos+len);
		mark_inode_dirty(dir);
	}
	unlock_page(page);
}

static int sysv_handle_dirsync(struct inode *dir)
{
	int err;

	err = filemap_write_and_wait(dir->i_mapping);
	if (!err)
		err = sync_inode_metadata(dir, 1);
	return err;
}

static struct page * dir_get_page(struct inode *dir, unsigned long n)
{
	struct address_space *mapping = dir->i_mapping;
	struct page *page = read_mapping_page(mapping, n, NULL);
	if (!IS_ERR(page))
		kmap(page);
	return page;
}

static int sysv_readdir(struct file *file, struct dir_context *ctx)
{
	unsigned long pos = ctx->pos;
	struct inode *inode = file_inode(file);
	struct super_block *sb = inode->i_sb;
	unsigned long npages = dir_pages(inode);
	unsigned offset;
	unsigned long n;

	ctx->pos = pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1);
	if (pos >= inode->i_size)
		return 0;

	offset = pos & ~PAGE_MASK;
	n = pos >> PAGE_SHIFT;

	for ( ; n < npages; n++, offset = 0) {
		char *kaddr, *limit;
		struct sysv_dir_entry *de;
		struct page *page = dir_get_page(inode, n);

		if (IS_ERR(page))
			continue;
		kaddr = (char *)page_address(page);
		de = (struct sysv_dir_entry *)(kaddr+offset);
		limit = kaddr + PAGE_SIZE - SYSV_DIRSIZE;
		for ( ;(char*)de <= limit; de++, ctx->pos += sizeof(*de)) {
			char *name = de->name;

			if (!de->inode)
				continue;

			if (!dir_emit(ctx, name, strnlen(name,SYSV_NAMELEN),
					fs16_to_cpu(SYSV_SB(sb), de->inode),
					DT_UNKNOWN)) {
				dir_put_page(page);
				return 0;
			}
		}
		dir_put_page(page);
	}
	return 0;
}

/* compare strings: name[0..len-1] (not zero-terminated) and
 * buffer[0..] (filled with zeroes up to buffer[0..maxlen-1])
 */
static inline int namecompare(int len, int maxlen,
	const char * name, const char * buffer)
{
	if (len < maxlen && buffer[len])
		return 0;
	return !memcmp(name, buffer, len);
}

/*
 *	sysv_find_entry()
 *
 * finds an entry in the specified directory with the wanted name. It
 * returns the cache buffer in which the entry was found, and the entry
 * itself (as a parameter - res_dir). It does NOT read the inode of the
 * entry - you'll have to do that yourself if you want to.
 */
struct sysv_dir_entry *sysv_find_entry(struct dentry *dentry, struct page **res_page)
{
	const char * name = dentry->d_name.name;
	int namelen = dentry->d_name.len;
	struct inode * dir = d_inode(dentry->d_parent);
	unsigned long start, n;
	unsigned long npages = dir_pages(dir);
	struct page *page = NULL;
	struct sysv_dir_entry *de;

	*res_page = NULL;

	start = SYSV_I(dir)->i_dir_start_lookup;
	if (start >= npages)
		start = 0;
	n = start;

	do {
		char *kaddr;
		page = dir_get_page(dir, n);
		if (!IS_ERR(page)) {
			kaddr = (char*)page_address(page);
			de = (struct sysv_dir_entry *) kaddr;
			kaddr += PAGE_SIZE - SYSV_DIRSIZE;
			for ( ; (char *) de <= kaddr ; de++) {
				if (!de->inode)
					continue;
				if (namecompare(namelen, SYSV_NAMELEN,
							name, de->name))
					goto found;
			}
			dir_put_page(page);
		}

		if (++n >= npages)
			n = 0;
	} while (n != start);

	return NULL;

found:
	SYSV_I(dir)->i_dir_start_lookup = n;
	*res_page = page;
	return de;
}

int sysv_add_link(struct dentry *dentry, struct inode *inode)
{
	struct inode *dir = d_inode(dentry->d_parent);
	const char * name = dentry->d_name.name;
	int namelen = dentry->d_name.len;
	struct page *page = NULL;
	struct sysv_dir_entry * de;
	unsigned long npages = dir_pages(dir);
	unsigned long n;
	char *kaddr;
	loff_t pos;
	int err;

	/* We take care of directory expansion in the same loop */
	for (n = 0; n <= npages; n++) {
		page = dir_get_page(dir, n);
		err = PTR_ERR(page);
		if (IS_ERR(page))
			goto out;
		kaddr = (char*)page_address(page);
		de = (struct sysv_dir_entry *)kaddr;
		kaddr += PAGE_SIZE - SYSV_DIRSIZE;
		while ((char *)de <= kaddr) {
			if (!de->inode)
				goto got_it;
			err = -EEXIST;
			if (namecompare(namelen, SYSV_NAMELEN, name, de->name)) 
				goto out_page;
			de++;
		}
		dir_put_page(page);
	}
	BUG();
	return -EINVAL;

got_it:
	pos = page_offset(page) + offset_in_page(de);
	lock_page(page);
	err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
	if (err)
		goto out_unlock;
	memcpy (de->name, name, namelen);
	memset (de->name + namelen, 0, SYSV_DIRSIZE - namelen - 2);
	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
	dir_commit_chunk(page, pos, SYSV_DIRSIZE);
	dir->i_mtime = dir->i_ctime = current_time(dir);
	mark_inode_dirty(dir);
	err = sysv_handle_dirsync(dir);
out_page:
	dir_put_page(page);
out:
	return err;
out_unlock:
	unlock_page(page);
	goto out_page;
}

int sysv_delete_entry(struct sysv_dir_entry *de, struct page *page)
{
	struct inode *inode = page->mapping->host;
	loff_t pos = page_offset(page) + offset_in_page(de);
	int err;

	lock_page(page);
	err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
	BUG_ON(err);
	de->inode = 0;
	dir_commit_chunk(page, pos, SYSV_DIRSIZE);
	dir_put_page(page);
	inode->i_ctime = inode->i_mtime = current_time(inode);
	mark_inode_dirty(inode);
	return sysv_handle_dirsync(inode);
}

int sysv_make_empty(struct inode *inode, struct inode *dir)
{
	struct page *page = grab_cache_page(inode->i_mapping, 0);
	struct sysv_dir_entry * de;
	char *base;
	int err;

	if (!page)
		return -ENOMEM;
	err = sysv_prepare_chunk(page, 0, 2 * SYSV_DIRSIZE);
	if (err) {
		unlock_page(page);
		goto fail;
	}
	kmap(page);

	base = (char*)page_address(page);
	memset(base, 0, PAGE_SIZE);

	de = (struct sysv_dir_entry *) base;
	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
	strcpy(de->name,".");
	de++;
	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), dir->i_ino);
	strcpy(de->name,"..");

	kunmap(page);
	dir_commit_chunk(page, 0, 2 * SYSV_DIRSIZE);
	err = sysv_handle_dirsync(inode);
fail:
	put_page(page);
	return err;
}

/*
 * routine to check that the specified directory is empty (for rmdir)
 */
int sysv_empty_dir(struct inode * inode)
{
	struct super_block *sb = inode->i_sb;
	struct page *page = NULL;
	unsigned long i, npages = dir_pages(inode);

	for (i = 0; i < npages; i++) {
		char *kaddr;
		struct sysv_dir_entry * de;
		page = dir_get_page(inode, i);

		if (IS_ERR(page))
			continue;

		kaddr = (char *)page_address(page);
		de = (struct sysv_dir_entry *)kaddr;
		kaddr += PAGE_SIZE-SYSV_DIRSIZE;

		for ( ;(char *)de <= kaddr; de++) {
			if (!de->inode)
				continue;
			/* check for . and .. */
			if (de->name[0] != '.')
				goto not_empty;
			if (!de->name[1]) {
				if (de->inode == cpu_to_fs16(SYSV_SB(sb),
							inode->i_ino))
					continue;
				goto not_empty;
			}
			if (de->name[1] != '.' || de->name[2])
				goto not_empty;
		}
		dir_put_page(page);
	}
	return 1;

not_empty:
	dir_put_page(page);
	return 0;
}

/* Releases the page */
void sysv_set_link(struct sysv_dir_entry *de, struct page *page,
	struct inode *inode)
{
	struct inode *dir = page->mapping->host;
	loff_t pos = page_offset(page) + offset_in_page(de);
	int err;

	lock_page(page);
	err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
	BUG_ON(err);
	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
	dir_commit_chunk(page, pos, SYSV_DIRSIZE);
	dir_put_page(page);
	dir->i_mtime = dir->i_ctime = current_time(dir);
	mark_inode_dirty(dir);
	sysv_handle_dirsync(inode);
}

struct sysv_dir_entry * sysv_dotdot (struct inode *dir, struct page **p)
{
	struct page *page = dir_get_page(dir, 0);
	struct sysv_dir_entry *de = NULL;

	if (!IS_ERR(page)) {
		de = (struct sysv_dir_entry*) page_address(page) + 1;
		*p = page;
	}
	return de;
}

ino_t sysv_inode_by_name(struct dentry *dentry)
{
	struct page *page;
	struct sysv_dir_entry *de = sysv_find_entry (dentry, &page);
	ino_t res = 0;
	
	if (de) {
		res = fs16_to_cpu(SYSV_SB(dentry->d_sb), de->inode);
		dir_put_page(page);
	}
	return res;
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* linux/fs/sysv/dir.c
	4	*
	5	* minix/dir.c
	6	* Copyright (C) 1991, 1992 Linus Torvalds
	7	*
	8	* coh/dir.c
	9	* Copyright (C) 1993 Pascal Haible, Bruno Haible
	10	*
	11	* sysv/dir.c
	12	* Copyright (C) 1993 Bruno Haible
	13	*
	14	* SystemV/Coherent directory handling functions
	15	*/
	16
	17	#include <linux/pagemap.h>
	18	#include <linux/highmem.h>
26a6441a	19	#include <linux/swap.h>
1da177e4 LT	20	#include "sysv.h"
1da177e4 LT	21
80886298	22	static int sysv_readdir(struct file , struct dir_context );
1da177e4	23
4b6f5d20	24	const struct file_operations sysv_dir_operations = {
5ac3455a	25	.llseek = generic_file_llseek,
1da177e4	26	.read = generic_read_dir,
3b0a3c1a	27	.iterate_shared = sysv_readdir,
1b061d92	28	.fsync = generic_file_fsync,
1da177e4 LT	29	};
	30
	31	static inline void dir_put_page(struct page *page)
	32	{
	33	kunmap(page);
09cbfeaf	34	put_page(page);
1da177e4 LT	35	}
1da177e4 LT	36
4309093e	37	static void dir_commit_chunk(struct page *page, loff_t pos, unsigned len)
1da177e4	38	{
26a6441a NP	39	struct address_space *mapping = page->mapping;
26a6441a NP	40	struct inode *dir = mapping->host;
1da177e4	41
26a6441a NP	42	block_write_end(NULL, mapping, pos, len, len, page, NULL);
	43	if (pos+len > dir->i_size) {
	44	i_size_write(dir, pos+len);
	45	mark_inode_dirty(dir);
	46	}
4309093e CH	47	unlock_page(page);
	48	}
	49
	50	static int sysv_handle_dirsync(struct inode *dir)
	51	{
	52	int err;
	53
	54	err = filemap_write_and_wait(dir->i_mapping);
	55	if (!err)
	56	err = sync_inode_metadata(dir, 1);
1da177e4 LT	57	return err;
	58	}
	59
	60	static struct page * dir_get_page(struct inode *dir, unsigned long n)
	61	{
	62	struct address_space *mapping = dir->i_mapping;
090d2b18	63	struct page *page = read_mapping_page(mapping, n, NULL);
6fe6900e	64	if (!IS_ERR(page))
1da177e4	65	kmap(page);
1da177e4	66	return page;
1da177e4 LT	67	}
1da177e4 LT	68
80886298	69	static int sysv_readdir(struct file file, struct dir_context ctx)
1da177e4	70	{
80886298 AV	71	unsigned long pos = ctx->pos;
80886298 AV	72	struct inode *inode = file_inode(file);
1da177e4	73	struct super_block *sb = inode->i_sb;
1da177e4	74	unsigned long npages = dir_pages(inode);
80886298 AV	75	unsigned offset;
80886298 AV	76	unsigned long n;
1da177e4	77
80886298	78	ctx->pos = pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1);
1da177e4	79	if (pos >= inode->i_size)
80886298 AV	80	return 0;
80886298 AV	81
09cbfeaf KS	82	offset = pos & ~PAGE_MASK;
09cbfeaf KS	83	n = pos >> PAGE_SHIFT;
1da177e4 LT	84
	85	for ( ; n < npages; n++, offset = 0) {
	86	char kaddr, limit;
	87	struct sysv_dir_entry *de;
	88	struct page *page = dir_get_page(inode, n);
	89
	90	if (IS_ERR(page))
	91	continue;
	92	kaddr = (char *)page_address(page);
	93	de = (struct sysv_dir_entry *)(kaddr+offset);
09cbfeaf	94	limit = kaddr + PAGE_SIZE - SYSV_DIRSIZE;
80886298	95	for ( ;(char)de <= limit; de++, ctx->pos += sizeof(de)) {
1da177e4	96	char *name = de->name;
1da177e4 LT	97
	98	if (!de->inode)
	99	continue;
	100
80886298	101	if (!dir_emit(ctx, name, strnlen(name,SYSV_NAMELEN),
1da177e4	102	fs16_to_cpu(SYSV_SB(sb), de->inode),
80886298	103	DT_UNKNOWN)) {
1da177e4	104	dir_put_page(page);
80886298	105	return 0;
1da177e4 LT	106	}
	107	}
	108	dir_put_page(page);
	109	}
1da177e4 LT	110	return 0;
	111	}
	112
	113	/* compare strings: name[0..len-1] (not zero-terminated) and
	114	* buffer[0..] (filled with zeroes up to buffer[0..maxlen-1])
	115	*/
	116	static inline int namecompare(int len, int maxlen,
	117	const char * name, const char * buffer)
	118	{
	119	if (len < maxlen && buffer[len])
	120	return 0;
	121	return !memcmp(name, buffer, len);
	122	}
	123
	124	/*
	125	* sysv_find_entry()
	126	*
	127	* finds an entry in the specified directory with the wanted name. It
	128	* returns the cache buffer in which the entry was found, and the entry
	129	* itself (as a parameter - res_dir). It does NOT read the inode of the
	130	* entry - you'll have to do that yourself if you want to.
	131	*/
	132	struct sysv_dir_entry sysv_find_entry(struct dentry dentry, struct page **res_page)
	133	{
	134	const char * name = dentry->d_name.name;
	135	int namelen = dentry->d_name.len;
2b0143b5	136	struct inode * dir = d_inode(dentry->d_parent);
1da177e4 LT	137	unsigned long start, n;
	138	unsigned long npages = dir_pages(dir);
	139	struct page *page = NULL;
	140	struct sysv_dir_entry *de;
	141
	142	*res_page = NULL;
	143
	144	start = SYSV_I(dir)->i_dir_start_lookup;
	145	if (start >= npages)
	146	start = 0;
	147	n = start;
	148
	149	do {
	150	char *kaddr;
	151	page = dir_get_page(dir, n);
	152	if (!IS_ERR(page)) {
	153	kaddr = (char*)page_address(page);
	154	de = (struct sysv_dir_entry *) kaddr;
09cbfeaf	155	kaddr += PAGE_SIZE - SYSV_DIRSIZE;
1da177e4 LT	156	for ( ; (char *) de <= kaddr ; de++) {
	157	if (!de->inode)
	158	continue;
	159	if (namecompare(namelen, SYSV_NAMELEN,
	160	name, de->name))
	161	goto found;
	162	}
404e7812	163	dir_put_page(page);
1da177e4	164	}
1da177e4 LT	165
	166	if (++n >= npages)
	167	n = 0;
	168	} while (n != start);
	169
	170	return NULL;
	171
	172	found:
	173	SYSV_I(dir)->i_dir_start_lookup = n;
	174	*res_page = page;
	175	return de;
	176	}
	177
	178	int sysv_add_link(struct dentry dentry, struct inode inode)
	179	{
2b0143b5	180	struct inode *dir = d_inode(dentry->d_parent);
1da177e4 LT	181	const char * name = dentry->d_name.name;
	182	int namelen = dentry->d_name.len;
	183	struct page *page = NULL;
	184	struct sysv_dir_entry * de;
	185	unsigned long npages = dir_pages(dir);
	186	unsigned long n;
	187	char *kaddr;
26a6441a	188	loff_t pos;
1da177e4 LT	189	int err;
	190
	191	/* We take care of directory expansion in the same loop */
	192	for (n = 0; n <= npages; n++) {
	193	page = dir_get_page(dir, n);
	194	err = PTR_ERR(page);
	195	if (IS_ERR(page))
	196	goto out;
	197	kaddr = (char*)page_address(page);
	198	de = (struct sysv_dir_entry *)kaddr;
09cbfeaf	199	kaddr += PAGE_SIZE - SYSV_DIRSIZE;
1da177e4 LT	200	while ((char *)de <= kaddr) {
	201	if (!de->inode)
	202	goto got_it;
	203	err = -EEXIST;
	204	if (namecompare(namelen, SYSV_NAMELEN, name, de->name))
	205	goto out_page;
	206	de++;
	207	}
	208	dir_put_page(page);
	209	}
	210	BUG();
	211	return -EINVAL;
	212
	213	got_it:
4bb1a137	214	pos = page_offset(page) + offset_in_page(de);
1da177e4	215	lock_page(page);
f4e420dc	216	err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
1da177e4 LT	217	if (err)
	218	goto out_unlock;
	219	memcpy (de->name, name, namelen);
	220	memset (de->name + namelen, 0, SYSV_DIRSIZE - namelen - 2);
	221	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
4309093e	222	dir_commit_chunk(page, pos, SYSV_DIRSIZE);
02027d42	223	dir->i_mtime = dir->i_ctime = current_time(dir);
1da177e4	224	mark_inode_dirty(dir);
4309093e	225	err = sysv_handle_dirsync(dir);
1da177e4 LT	226	out_page:
	227	dir_put_page(page);
	228	out:
	229	return err;
	230	out_unlock:
	231	unlock_page(page);
	232	goto out_page;
	233	}
	234
	235	int sysv_delete_entry(struct sysv_dir_entry de, struct page page)
	236	{
f4e420dc	237	struct inode *inode = page->mapping->host;
4bb1a137	238	loff_t pos = page_offset(page) + offset_in_page(de);
1da177e4 LT	239	int err;
	240
	241	lock_page(page);
f4e420dc	242	err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
d6735bfc	243	BUG_ON(err);
1da177e4	244	de->inode = 0;
4309093e	245	dir_commit_chunk(page, pos, SYSV_DIRSIZE);
1da177e4	246	dir_put_page(page);
02027d42	247	inode->i_ctime = inode->i_mtime = current_time(inode);
1da177e4	248	mark_inode_dirty(inode);
4309093e	249	return sysv_handle_dirsync(inode);
1da177e4 LT	250	}
	251
	252	int sysv_make_empty(struct inode inode, struct inode dir)
	253	{
f4e420dc	254	struct page *page = grab_cache_page(inode->i_mapping, 0);
1da177e4 LT	255	struct sysv_dir_entry * de;
	256	char *base;
	257	int err;
	258
	259	if (!page)
	260	return -ENOMEM;
f4e420dc	261	err = sysv_prepare_chunk(page, 0, 2 * SYSV_DIRSIZE);
1da177e4 LT	262	if (err) {
	263	unlock_page(page);
	264	goto fail;
	265	}
26a6441a	266	kmap(page);
1da177e4 LT	267
1da177e4 LT	268	base = (char*)page_address(page);
09cbfeaf	269	memset(base, 0, PAGE_SIZE);
1da177e4 LT	270
	271	de = (struct sysv_dir_entry *) base;
	272	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
	273	strcpy(de->name,".");
	274	de++;
	275	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), dir->i_ino);
	276	strcpy(de->name,"..");
	277
26a6441a	278	kunmap(page);
4309093e CH	279	dir_commit_chunk(page, 0, 2 * SYSV_DIRSIZE);
4309093e CH	280	err = sysv_handle_dirsync(inode);
1da177e4	281	fail:
09cbfeaf	282	put_page(page);
1da177e4 LT	283	return err;
	284	}
	285
	286	/*
	287	* routine to check that the specified directory is empty (for rmdir)
	288	*/
	289	int sysv_empty_dir(struct inode * inode)
	290	{
	291	struct super_block *sb = inode->i_sb;
	292	struct page *page = NULL;
	293	unsigned long i, npages = dir_pages(inode);
	294
	295	for (i = 0; i < npages; i++) {
	296	char *kaddr;
	297	struct sysv_dir_entry * de;
	298	page = dir_get_page(inode, i);
	299
	300	if (IS_ERR(page))
	301	continue;
	302
	303	kaddr = (char *)page_address(page);
	304	de = (struct sysv_dir_entry *)kaddr;
09cbfeaf	305	kaddr += PAGE_SIZE-SYSV_DIRSIZE;
1da177e4 LT	306
	307	for ( ;(char *)de <= kaddr; de++) {
	308	if (!de->inode)
	309	continue;
	310	/* check for . and .. */
	311	if (de->name[0] != '.')
	312	goto not_empty;
	313	if (!de->name[1]) {
	314	if (de->inode == cpu_to_fs16(SYSV_SB(sb),
	315	inode->i_ino))
	316	continue;
	317	goto not_empty;
	318	}
	319	if (de->name[1] != '.' \|\| de->name[2])
	320	goto not_empty;
	321	}
	322	dir_put_page(page);
	323	}
	324	return 1;
	325
	326	not_empty:
	327	dir_put_page(page);
	328	return 0;
	329	}
	330
	331	/* Releases the page */
	332	void sysv_set_link(struct sysv_dir_entry de, struct page page,
	333	struct inode *inode)
	334	{
f4e420dc	335	struct inode *dir = page->mapping->host;
4bb1a137	336	loff_t pos = page_offset(page) + offset_in_page(de);
1da177e4 LT	337	int err;
	338
	339	lock_page(page);
f4e420dc	340	err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
d6735bfc	341	BUG_ON(err);
1da177e4	342	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
4309093e	343	dir_commit_chunk(page, pos, SYSV_DIRSIZE);
1da177e4	344	dir_put_page(page);
02027d42	345	dir->i_mtime = dir->i_ctime = current_time(dir);
1da177e4	346	mark_inode_dirty(dir);
4309093e	347	sysv_handle_dirsync(inode);
1da177e4 LT	348	}
	349
	350	struct sysv_dir_entry * sysv_dotdot (struct inode dir, struct page *p)
	351	{
	352	struct page *page = dir_get_page(dir, 0);
	353	struct sysv_dir_entry *de = NULL;
	354
	355	if (!IS_ERR(page)) {
	356	de = (struct sysv_dir_entry*) page_address(page) + 1;
	357	*p = page;
	358	}
	359	return de;
	360	}
	361
	362	ino_t sysv_inode_by_name(struct dentry *dentry)
	363	{
	364	struct page *page;
	365	struct sysv_dir_entry *de = sysv_find_entry (dentry, &page);
	366	ino_t res = 0;
	367
	368	if (de) {
	369	res = fs16_to_cpu(SYSV_SB(dentry->d_sb), de->inode);
	370	dir_put_page(page);
	371	}
	372	return res;
	373	}