[linux.git] / fs / sysv / dir.c

/*
 *  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 *, void *, filldir_t);

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

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

static inline unsigned long dir_pages(struct inode *inode)
{
	return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT;
}

static int dir_commit_chunk(struct page *page, loff_t pos, unsigned len)
{
	struct address_space *mapping = page->mapping;
	struct inode *dir = mapping->host;
	int err = 0;

	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);
	}
	if (IS_DIRSYNC(dir))
		err = write_one_page(page, 1);
	else
		unlock_page(page);
	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 * filp, void * dirent, filldir_t filldir)
{
	unsigned long pos = filp->f_pos;
	struct inode *inode = file_inode(filp);
	struct super_block *sb = inode->i_sb;
	unsigned offset = pos & ~PAGE_CACHE_MASK;
	unsigned long n = pos >> PAGE_CACHE_SHIFT;
	unsigned long npages = dir_pages(inode);

	pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1);
	if (pos >= inode->i_size)
		goto done;

	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_CACHE_SIZE - SYSV_DIRSIZE;
		for ( ;(char*)de <= limit; de++) {
			char *name = de->name;
			int over;

			if (!de->inode)
				continue;

			offset = (char *)de - kaddr;

			over = filldir(dirent, name, strnlen(name,SYSV_NAMELEN),
					((loff_t)n<<PAGE_CACHE_SHIFT) | offset,
					fs16_to_cpu(SYSV_SB(sb), de->inode),
					DT_UNKNOWN);
			if (over) {
				dir_put_page(page);
				goto done;
			}
		}
		dir_put_page(page);
	}

done:
	filp->f_pos = ((loff_t)n << PAGE_CACHE_SHIFT) | offset;
	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 = dentry->d_parent->d_inode;
	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_CACHE_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 = dentry->d_parent->d_inode;
	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_CACHE_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) +
			(char*)de - (char*)page_address(page);
	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);
	err = dir_commit_chunk(page, pos, SYSV_DIRSIZE);
	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
	mark_inode_dirty(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;
	char *kaddr = (char*)page_address(page);
	loff_t pos = page_offset(page) + (char *)de - kaddr;
	int err;

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

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_CACHE_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);
	err = dir_commit_chunk(page, 0, 2 * SYSV_DIRSIZE);
fail:
	page_cache_release(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_CACHE_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) +
			(char *)de-(char*)page_address(page);
	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);
	err = dir_commit_chunk(page, pos, SYSV_DIRSIZE);
	dir_put_page(page);
	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
	mark_inode_dirty(dir);
}

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
1da177e4 LT	1	/*
	2	* linux/fs/sysv/dir.c
	3	*
	4	* minix/dir.c
	5	* Copyright (C) 1991, 1992 Linus Torvalds
	6	*
	7	* coh/dir.c
	8	* Copyright (C) 1993 Pascal Haible, Bruno Haible
	9	*
	10	* sysv/dir.c
	11	* Copyright (C) 1993 Bruno Haible
	12	*
	13	* SystemV/Coherent directory handling functions
	14	*/
	15
	16	#include <linux/pagemap.h>
	17	#include <linux/highmem.h>
26a6441a	18	#include <linux/swap.h>
1da177e4 LT	19	#include "sysv.h"
	20
	21	static int sysv_readdir(struct file , void , filldir_t);
	22
4b6f5d20	23	const struct file_operations sysv_dir_operations = {
5ac3455a	24	.llseek = generic_file_llseek,
1da177e4 LT	25	.read = generic_read_dir,
1da177e4 LT	26	.readdir = sysv_readdir,
1b061d92	27	.fsync = generic_file_fsync,
1da177e4 LT	28	};
	29
	30	static inline void dir_put_page(struct page *page)
	31	{
	32	kunmap(page);
	33	page_cache_release(page);
	34	}
	35
	36	static inline unsigned long dir_pages(struct inode *inode)
	37	{
	38	return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT;
	39	}
	40
26a6441a	41	static int dir_commit_chunk(struct page *page, loff_t pos, unsigned len)
1da177e4	42	{
26a6441a NP	43	struct address_space *mapping = page->mapping;
26a6441a NP	44	struct inode *dir = mapping->host;
1da177e4 LT	45	int err = 0;
1da177e4 LT	46
26a6441a NP	47	block_write_end(NULL, mapping, pos, len, len, page, NULL);
	48	if (pos+len > dir->i_size) {
	49	i_size_write(dir, pos+len);
	50	mark_inode_dirty(dir);
	51	}
1da177e4 LT	52	if (IS_DIRSYNC(dir))
	53	err = write_one_page(page, 1);
	54	else
	55	unlock_page(page);
	56	return err;
	57	}
	58
	59	static struct page * dir_get_page(struct inode *dir, unsigned long n)
	60	{
	61	struct address_space *mapping = dir->i_mapping;
090d2b18	62	struct page *page = read_mapping_page(mapping, n, NULL);
6fe6900e	63	if (!IS_ERR(page))
1da177e4	64	kmap(page);
1da177e4	65	return page;
1da177e4 LT	66	}
	67
	68	static int sysv_readdir(struct file * filp, void * dirent, filldir_t filldir)
	69	{
	70	unsigned long pos = filp->f_pos;
496ad9aa	71	struct inode *inode = file_inode(filp);
1da177e4 LT	72	struct super_block *sb = inode->i_sb;
	73	unsigned offset = pos & ~PAGE_CACHE_MASK;
	74	unsigned long n = pos >> PAGE_CACHE_SHIFT;
	75	unsigned long npages = dir_pages(inode);
	76
1da177e4 LT	77	pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1);
	78	if (pos >= inode->i_size)
	79	goto done;
	80
	81	for ( ; n < npages; n++, offset = 0) {
	82	char kaddr, limit;
	83	struct sysv_dir_entry *de;
	84	struct page *page = dir_get_page(inode, n);
	85
	86	if (IS_ERR(page))
	87	continue;
	88	kaddr = (char *)page_address(page);
	89	de = (struct sysv_dir_entry *)(kaddr+offset);
	90	limit = kaddr + PAGE_CACHE_SIZE - SYSV_DIRSIZE;
	91	for ( ;(char*)de <= limit; de++) {
	92	char *name = de->name;
	93	int over;
	94
	95	if (!de->inode)
	96	continue;
	97
	98	offset = (char *)de - kaddr;
	99
	100	over = filldir(dirent, name, strnlen(name,SYSV_NAMELEN),
54b21a79	101	((loff_t)n<<PAGE_CACHE_SHIFT) \| offset,
1da177e4 LT	102	fs16_to_cpu(SYSV_SB(sb), de->inode),
	103	DT_UNKNOWN);
	104	if (over) {
	105	dir_put_page(page);
	106	goto done;
	107	}
	108	}
	109	dir_put_page(page);
	110	}
	111
	112	done:
54b21a79	113	filp->f_pos = ((loff_t)n << PAGE_CACHE_SHIFT) \| offset;
1da177e4 LT	114	return 0;
	115	}
	116
	117	/* compare strings: name[0..len-1] (not zero-terminated) and
	118	* buffer[0..] (filled with zeroes up to buffer[0..maxlen-1])
	119	*/
	120	static inline int namecompare(int len, int maxlen,
	121	const char * name, const char * buffer)
	122	{
	123	if (len < maxlen && buffer[len])
	124	return 0;
	125	return !memcmp(name, buffer, len);
	126	}
	127
	128	/*
	129	* sysv_find_entry()
	130	*
	131	* finds an entry in the specified directory with the wanted name. It
	132	* returns the cache buffer in which the entry was found, and the entry
	133	* itself (as a parameter - res_dir). It does NOT read the inode of the
	134	* entry - you'll have to do that yourself if you want to.
	135	*/
	136	struct sysv_dir_entry sysv_find_entry(struct dentry dentry, struct page **res_page)
	137	{
	138	const char * name = dentry->d_name.name;
	139	int namelen = dentry->d_name.len;
	140	struct inode * dir = dentry->d_parent->d_inode;
	141	unsigned long start, n;
	142	unsigned long npages = dir_pages(dir);
	143	struct page *page = NULL;
	144	struct sysv_dir_entry *de;
	145
	146	*res_page = NULL;
	147
	148	start = SYSV_I(dir)->i_dir_start_lookup;
	149	if (start >= npages)
	150	start = 0;
	151	n = start;
	152
	153	do {
	154	char *kaddr;
	155	page = dir_get_page(dir, n);
	156	if (!IS_ERR(page)) {
	157	kaddr = (char*)page_address(page);
	158	de = (struct sysv_dir_entry *) kaddr;
	159	kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE;
	160	for ( ; (char *) de <= kaddr ; de++) {
	161	if (!de->inode)
	162	continue;
	163	if (namecompare(namelen, SYSV_NAMELEN,
	164	name, de->name))
	165	goto found;
	166	}
404e7812	167	dir_put_page(page);
1da177e4	168	}
1da177e4 LT	169
	170	if (++n >= npages)
	171	n = 0;
	172	} while (n != start);
	173
	174	return NULL;
	175
	176	found:
	177	SYSV_I(dir)->i_dir_start_lookup = n;
	178	*res_page = page;
	179	return de;
	180	}
	181
	182	int sysv_add_link(struct dentry dentry, struct inode inode)
	183	{
	184	struct inode *dir = dentry->d_parent->d_inode;
	185	const char * name = dentry->d_name.name;
	186	int namelen = dentry->d_name.len;
	187	struct page *page = NULL;
	188	struct sysv_dir_entry * de;
	189	unsigned long npages = dir_pages(dir);
	190	unsigned long n;
	191	char *kaddr;
26a6441a	192	loff_t pos;
1da177e4 LT	193	int err;
	194
	195	/* We take care of directory expansion in the same loop */
	196	for (n = 0; n <= npages; n++) {
	197	page = dir_get_page(dir, n);
	198	err = PTR_ERR(page);
	199	if (IS_ERR(page))
	200	goto out;
	201	kaddr = (char*)page_address(page);
	202	de = (struct sysv_dir_entry *)kaddr;
	203	kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE;
	204	while ((char *)de <= kaddr) {
	205	if (!de->inode)
	206	goto got_it;
	207	err = -EEXIST;
	208	if (namecompare(namelen, SYSV_NAMELEN, name, de->name))
	209	goto out_page;
	210	de++;
	211	}
	212	dir_put_page(page);
	213	}
	214	BUG();
	215	return -EINVAL;
	216
	217	got_it:
26a6441a NP	218	pos = page_offset(page) +
26a6441a NP	219	(char)de - (char)page_address(page);
1da177e4	220	lock_page(page);
f4e420dc	221	err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
1da177e4 LT	222	if (err)
	223	goto out_unlock;
	224	memcpy (de->name, name, namelen);
	225	memset (de->name + namelen, 0, SYSV_DIRSIZE - namelen - 2);
	226	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
26a6441a	227	err = dir_commit_chunk(page, pos, SYSV_DIRSIZE);
1da177e4 LT	228	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
	229	mark_inode_dirty(dir);
	230	out_page:
	231	dir_put_page(page);
	232	out:
	233	return err;
	234	out_unlock:
	235	unlock_page(page);
	236	goto out_page;
	237	}
	238
	239	int sysv_delete_entry(struct sysv_dir_entry de, struct page page)
	240	{
f4e420dc	241	struct inode *inode = page->mapping->host;
1da177e4	242	char kaddr = (char)page_address(page);
26a6441a	243	loff_t pos = page_offset(page) + (char *)de - kaddr;
1da177e4 LT	244	int err;
	245
	246	lock_page(page);
f4e420dc	247	err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
d6735bfc	248	BUG_ON(err);
1da177e4	249	de->inode = 0;
26a6441a	250	err = dir_commit_chunk(page, pos, SYSV_DIRSIZE);
1da177e4 LT	251	dir_put_page(page);
	252	inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
	253	mark_inode_dirty(inode);
	254	return err;
	255	}
	256
	257	int sysv_make_empty(struct inode inode, struct inode dir)
	258	{
f4e420dc	259	struct page *page = grab_cache_page(inode->i_mapping, 0);
1da177e4 LT	260	struct sysv_dir_entry * de;
	261	char *base;
	262	int err;
	263
	264	if (!page)
	265	return -ENOMEM;
f4e420dc	266	err = sysv_prepare_chunk(page, 0, 2 * SYSV_DIRSIZE);
1da177e4 LT	267	if (err) {
	268	unlock_page(page);
	269	goto fail;
	270	}
26a6441a	271	kmap(page);
1da177e4 LT	272
	273	base = (char*)page_address(page);
	274	memset(base, 0, PAGE_CACHE_SIZE);
	275
	276	de = (struct sysv_dir_entry *) base;
	277	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
	278	strcpy(de->name,".");
	279	de++;
	280	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), dir->i_ino);
	281	strcpy(de->name,"..");
	282
26a6441a	283	kunmap(page);
1da177e4 LT	284	err = dir_commit_chunk(page, 0, 2 * SYSV_DIRSIZE);
1da177e4 LT	285	fail:
1da177e4 LT	286	page_cache_release(page);
	287	return err;
	288	}
	289
	290	/*
	291	* routine to check that the specified directory is empty (for rmdir)
	292	*/
	293	int sysv_empty_dir(struct inode * inode)
	294	{
	295	struct super_block *sb = inode->i_sb;
	296	struct page *page = NULL;
	297	unsigned long i, npages = dir_pages(inode);
	298
	299	for (i = 0; i < npages; i++) {
	300	char *kaddr;
	301	struct sysv_dir_entry * de;
	302	page = dir_get_page(inode, i);
	303
	304	if (IS_ERR(page))
	305	continue;
	306
	307	kaddr = (char *)page_address(page);
	308	de = (struct sysv_dir_entry *)kaddr;
	309	kaddr += PAGE_CACHE_SIZE-SYSV_DIRSIZE;
	310
	311	for ( ;(char *)de <= kaddr; de++) {
	312	if (!de->inode)
	313	continue;
	314	/* check for . and .. */
	315	if (de->name[0] != '.')
	316	goto not_empty;
	317	if (!de->name[1]) {
	318	if (de->inode == cpu_to_fs16(SYSV_SB(sb),
	319	inode->i_ino))
	320	continue;
	321	goto not_empty;
	322	}
	323	if (de->name[1] != '.' \|\| de->name[2])
	324	goto not_empty;
	325	}
	326	dir_put_page(page);
	327	}
	328	return 1;
	329
	330	not_empty:
	331	dir_put_page(page);
	332	return 0;
	333	}
	334
	335	/* Releases the page */
	336	void sysv_set_link(struct sysv_dir_entry de, struct page page,
	337	struct inode *inode)
	338	{
f4e420dc	339	struct inode *dir = page->mapping->host;
26a6441a NP	340	loff_t pos = page_offset(page) +
26a6441a NP	341	(char )de-(char)page_address(page);
1da177e4 LT	342	int err;
	343
	344	lock_page(page);
f4e420dc	345	err = sysv_prepare_chunk(page, pos, SYSV_DIRSIZE);
d6735bfc	346	BUG_ON(err);
1da177e4	347	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
26a6441a	348	err = dir_commit_chunk(page, pos, SYSV_DIRSIZE);
1da177e4 LT	349	dir_put_page(page);
	350	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
	351	mark_inode_dirty(dir);
	352	}
	353
	354	struct sysv_dir_entry * sysv_dotdot (struct inode dir, struct page *p)
	355	{
	356	struct page *page = dir_get_page(dir, 0);
	357	struct sysv_dir_entry *de = NULL;
	358
	359	if (!IS_ERR(page)) {
	360	de = (struct sysv_dir_entry*) page_address(page) + 1;
	361	*p = page;
	362	}
	363	return de;
	364	}
	365
	366	ino_t sysv_inode_by_name(struct dentry *dentry)
	367	{
	368	struct page *page;
	369	struct sysv_dir_entry *de = sysv_find_entry (dentry, &page);
	370	ino_t res = 0;
	371
	372	if (de) {
	373	res = fs16_to_cpu(SYSV_SB(dentry->d_sb), de->inode);
	374	dir_put_page(page);
	375	}
	376	return res;
	377	}