[net-next-2.6.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/smp_lock.h>
#include "sysv.h"

static int sysv_readdir(struct file *, void *, filldir_t);

const struct file_operations sysv_dir_operations = {
	.read		= generic_read_dir,
	.readdir	= sysv_readdir,
	.fsync		= sysv_sync_file,
};

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, unsigned from, unsigned to)
{
	struct inode *dir = (struct inode *)page->mapping->host;
	int err = 0;

	page->mapping->a_ops->commit_write(NULL, page, from, to);
	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 = filp->f_path.dentry->d_inode;
	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);

	lock_kernel();

	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;
	unlock_kernel();
	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;
	unsigned from, to;
	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:
	from = (char*)de - (char*)page_address(page);
	to = from + SYSV_DIRSIZE;
	lock_page(page);
	err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
	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, from, to);
	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 address_space *mapping = page->mapping;
	struct inode *inode = (struct inode*)mapping->host;
	char *kaddr = (char*)page_address(page);
	unsigned from = (char*)de - kaddr;
	unsigned to = from + SYSV_DIRSIZE;
	int err;

	lock_page(page);
	err = mapping->a_ops->prepare_write(NULL, page, from, to);
	BUG_ON(err);
	de->inode = 0;
	err = dir_commit_chunk(page, from, to);
	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 address_space *mapping = inode->i_mapping;
	struct page *page = grab_cache_page(mapping, 0);
	struct sysv_dir_entry * de;
	char *base;
	int err;

	if (!page)
		return -ENOMEM;
	kmap(page);
	err = mapping->a_ops->prepare_write(NULL, page, 0, 2 * SYSV_DIRSIZE);
	if (err) {
		unlock_page(page);
		goto fail;
	}

	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,"..");

	err = dir_commit_chunk(page, 0, 2 * SYSV_DIRSIZE);
fail:
	kunmap(page);
	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 = (struct inode*)page->mapping->host;
	unsigned from = (char *)de-(char*)page_address(page);
	unsigned to = from + SYSV_DIRSIZE;
	int err;

	lock_page(page);
	err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
	BUG_ON(err);
	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
	err = dir_commit_chunk(page, from, to);
	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>
	18	#include <linux/smp_lock.h>
	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 = {
1da177e4 LT	24	.read = generic_read_dir,
	25	.readdir = sysv_readdir,
	26	.fsync = sysv_sync_file,
	27	};
	28
	29	static inline void dir_put_page(struct page *page)
	30	{
	31	kunmap(page);
	32	page_cache_release(page);
	33	}
	34
	35	static inline unsigned long dir_pages(struct inode *inode)
	36	{
	37	return (inode->i_size+PAGE_CACHE_SIZE-1)>>PAGE_CACHE_SHIFT;
	38	}
	39
	40	static int dir_commit_chunk(struct page *page, unsigned from, unsigned to)
	41	{
	42	struct inode dir = (struct inode )page->mapping->host;
	43	int err = 0;
	44
	45	page->mapping->a_ops->commit_write(NULL, page, from, to);
	46	if (IS_DIRSYNC(dir))
	47	err = write_one_page(page, 1);
	48	else
	49	unlock_page(page);
	50	return err;
	51	}
	52
	53	static struct page * dir_get_page(struct inode *dir, unsigned long n)
	54	{
	55	struct address_space *mapping = dir->i_mapping;
090d2b18	56	struct page *page = read_mapping_page(mapping, n, NULL);
6fe6900e	57	if (!IS_ERR(page))
1da177e4	58	kmap(page);
1da177e4	59	return page;
1da177e4 LT	60	}
	61
	62	static int sysv_readdir(struct file * filp, void * dirent, filldir_t filldir)
	63	{
	64	unsigned long pos = filp->f_pos;
5495ca65	65	struct inode *inode = filp->f_path.dentry->d_inode;
1da177e4 LT	66	struct super_block *sb = inode->i_sb;
	67	unsigned offset = pos & ~PAGE_CACHE_MASK;
	68	unsigned long n = pos >> PAGE_CACHE_SHIFT;
	69	unsigned long npages = dir_pages(inode);
	70
	71	lock_kernel();
	72
	73	pos = (pos + SYSV_DIRSIZE-1) & ~(SYSV_DIRSIZE-1);
	74	if (pos >= inode->i_size)
	75	goto done;
	76
	77	for ( ; n < npages; n++, offset = 0) {
	78	char kaddr, limit;
	79	struct sysv_dir_entry *de;
	80	struct page *page = dir_get_page(inode, n);
	81
	82	if (IS_ERR(page))
	83	continue;
	84	kaddr = (char *)page_address(page);
	85	de = (struct sysv_dir_entry *)(kaddr+offset);
	86	limit = kaddr + PAGE_CACHE_SIZE - SYSV_DIRSIZE;
	87	for ( ;(char*)de <= limit; de++) {
	88	char *name = de->name;
	89	int over;
	90
	91	if (!de->inode)
	92	continue;
	93
	94	offset = (char *)de - kaddr;
	95
	96	over = filldir(dirent, name, strnlen(name,SYSV_NAMELEN),
54b21a79	97	((loff_t)n<<PAGE_CACHE_SHIFT) \| offset,
1da177e4 LT	98	fs16_to_cpu(SYSV_SB(sb), de->inode),
	99	DT_UNKNOWN);
	100	if (over) {
	101	dir_put_page(page);
	102	goto done;
	103	}
	104	}
	105	dir_put_page(page);
	106	}
	107
	108	done:
54b21a79	109	filp->f_pos = ((loff_t)n << PAGE_CACHE_SHIFT) \| offset;
1da177e4 LT	110	unlock_kernel();
	111	return 0;
	112	}
	113
	114	/* compare strings: name[0..len-1] (not zero-terminated) and
	115	* buffer[0..] (filled with zeroes up to buffer[0..maxlen-1])
	116	*/
	117	static inline int namecompare(int len, int maxlen,
	118	const char * name, const char * buffer)
	119	{
	120	if (len < maxlen && buffer[len])
	121	return 0;
	122	return !memcmp(name, buffer, len);
	123	}
	124
	125	/*
	126	* sysv_find_entry()
	127	*
	128	* finds an entry in the specified directory with the wanted name. It
	129	* returns the cache buffer in which the entry was found, and the entry
	130	* itself (as a parameter - res_dir). It does NOT read the inode of the
	131	* entry - you'll have to do that yourself if you want to.
	132	*/
	133	struct sysv_dir_entry sysv_find_entry(struct dentry dentry, struct page **res_page)
	134	{
	135	const char * name = dentry->d_name.name;
	136	int namelen = dentry->d_name.len;
	137	struct inode * dir = dentry->d_parent->d_inode;
	138	unsigned long start, n;
	139	unsigned long npages = dir_pages(dir);
	140	struct page *page = NULL;
	141	struct sysv_dir_entry *de;
	142
	143	*res_page = NULL;
	144
	145	start = SYSV_I(dir)->i_dir_start_lookup;
	146	if (start >= npages)
	147	start = 0;
	148	n = start;
	149
	150	do {
	151	char *kaddr;
	152	page = dir_get_page(dir, n);
	153	if (!IS_ERR(page)) {
	154	kaddr = (char*)page_address(page);
	155	de = (struct sysv_dir_entry *) kaddr;
	156	kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE;
	157	for ( ; (char *) de <= kaddr ; de++) {
	158	if (!de->inode)
	159	continue;
	160	if (namecompare(namelen, SYSV_NAMELEN,
	161	name, de->name))
	162	goto found;
	163	}
	164	}
	165	dir_put_page(page);
	166
	167	if (++n >= npages)
	168	n = 0;
	169	} while (n != start);
	170
	171	return NULL;
	172
	173	found:
174	SYSV_I(dir)->i_dir_start_lookup = n;
175	*res_page = page;
176	return de;
177	}
178
179	int sysv_add_link(struct dentry dentry, struct inode inode)
180	{
181	struct inode *dir = dentry->d_parent->d_inode;
182	const char * name = dentry->d_name.name;
183	int namelen = dentry->d_name.len;
184	struct page *page = NULL;
185	struct sysv_dir_entry * de;
186	unsigned long npages = dir_pages(dir);
187	unsigned long n;
188	char *kaddr;
189	unsigned from, to;
190	int err;
191
192	/* We take care of directory expansion in the same loop */
193	for (n = 0; n <= npages; n++) {
194	page = dir_get_page(dir, n);
195	err = PTR_ERR(page);
196	if (IS_ERR(page))
197	goto out;
198	kaddr = (char*)page_address(page);
199	de = (struct sysv_dir_entry *)kaddr;
200	kaddr += PAGE_CACHE_SIZE - SYSV_DIRSIZE;
201	while ((char *)de <= kaddr) {
202	if (!de->inode)
203	goto got_it;
204	err = -EEXIST;
205	if (namecompare(namelen, SYSV_NAMELEN, name, de->name))
206	goto out_page;
207	de++;
208	}
209	dir_put_page(page);
210	}
211	BUG();
212	return -EINVAL;
213
214	got_it:
215	from = (char)de - (char)page_address(page);
216	to = from + SYSV_DIRSIZE;
217	lock_page(page);
218	err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
219	if (err)
220	goto out_unlock;
221	memcpy (de->name, name, namelen);
222	memset (de->name + namelen, 0, SYSV_DIRSIZE - namelen - 2);
223	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
224	err = dir_commit_chunk(page, from, to);
225	dir->i_mtime = dir->i_ctime = CURRENT_TIME_SEC;
226	mark_inode_dirty(dir);
227	out_page:
228	dir_put_page(page);
229	out:
230	return err;
231	out_unlock:
232	unlock_page(page);
233	goto out_page;
234	}
235
236	int sysv_delete_entry(struct sysv_dir_entry de, struct page page)
237	{
238	struct address_space *mapping = page->mapping;
239	struct inode inode = (struct inode)mapping->host;
240	char kaddr = (char)page_address(page);
241	unsigned from = (char*)de - kaddr;
242	unsigned to = from + SYSV_DIRSIZE;
243	int err;
244
245	lock_page(page);
246	err = mapping->a_ops->prepare_write(NULL, page, from, to);
d6735bfc	247	BUG_ON(err);
1da177e4 LT	248	de->inode = 0;
	249	err = dir_commit_chunk(page, from, to);
	250	dir_put_page(page);
	251	inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
	252	mark_inode_dirty(inode);
	253	return err;
	254	}
	255
	256	int sysv_make_empty(struct inode inode, struct inode dir)
	257	{
	258	struct address_space *mapping = inode->i_mapping;
	259	struct page *page = grab_cache_page(mapping, 0);
	260	struct sysv_dir_entry * de;
	261	char *base;
	262	int err;
	263
	264	if (!page)
	265	return -ENOMEM;
	266	kmap(page);
	267	err = mapping->a_ops->prepare_write(NULL, page, 0, 2 * SYSV_DIRSIZE);
	268	if (err) {
	269	unlock_page(page);
	270	goto fail;
	271	}
	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
	283	err = dir_commit_chunk(page, 0, 2 * SYSV_DIRSIZE);
	284	fail:
	285	kunmap(page);
	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	{
339	struct inode dir = (struct inode)page->mapping->host;
340	unsigned from = (char )de-(char)page_address(page);
341	unsigned to = from + SYSV_DIRSIZE;
342	int err;
343
344	lock_page(page);
345	err = page->mapping->a_ops->prepare_write(NULL, page, from, to);
d6735bfc	346	BUG_ON(err);
1da177e4 LT	347	de->inode = cpu_to_fs16(SYSV_SB(inode->i_sb), inode->i_ino);
	348	err = dir_commit_chunk(page, from, to);
	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	}