[net-next-2.6.git] / fs / jffs2 / file.c

/*
 * JFFS2 -- Journalling Flash File System, Version 2.
 *
 * Copyright © 2001-2007 Red Hat, Inc.
 * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
 *
 * Created by David Woodhouse <dwmw2@infradead.org>
 *
 * For licensing information, see the file 'LICENCE' in this directory.
 *
 */

#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/time.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/crc32.h>
#include <linux/jffs2.h>
#include "nodelist.h"

static int jffs2_write_end(struct file *filp, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned copied,
			struct page *pg, void *fsdata);
static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned flags,
			struct page **pagep, void **fsdata);
static int jffs2_readpage (struct file *filp, struct page *pg);

int jffs2_fsync(struct file *filp, int datasync)
{
	struct inode *inode = filp->f_mapping->host;
	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);

	/* Trigger GC to flush any pending writes for this inode */
	jffs2_flush_wbuf_gc(c, inode->i_ino);

	return 0;
}

const struct file_operations jffs2_file_operations =
{
	.llseek =	generic_file_llseek,
	.open =		generic_file_open,
 	.read =		do_sync_read,
 	.aio_read =	generic_file_aio_read,
 	.write =	do_sync_write,
 	.aio_write =	generic_file_aio_write,
	.unlocked_ioctl=jffs2_ioctl,
	.mmap =		generic_file_readonly_mmap,
	.fsync =	jffs2_fsync,
	.splice_read =	generic_file_splice_read,
};

/* jffs2_file_inode_operations */

const struct inode_operations jffs2_file_inode_operations =
{
	.check_acl =	jffs2_check_acl,
	.setattr =	jffs2_setattr,
	.setxattr =	jffs2_setxattr,
	.getxattr =	jffs2_getxattr,
	.listxattr =	jffs2_listxattr,
	.removexattr =	jffs2_removexattr
};

const struct address_space_operations jffs2_file_address_operations =
{
	.readpage =	jffs2_readpage,
	.write_begin =	jffs2_write_begin,
	.write_end =	jffs2_write_end,
};

static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg)
{
	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
	unsigned char *pg_buf;
	int ret;

	D2(printk(KERN_DEBUG "jffs2_do_readpage_nolock(): ino #%lu, page at offset 0x%lx\n", inode->i_ino, pg->index << PAGE_CACHE_SHIFT));

	BUG_ON(!PageLocked(pg));

	pg_buf = kmap(pg);
	/* FIXME: Can kmap fail? */

	ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE);

	if (ret) {
		ClearPageUptodate(pg);
		SetPageError(pg);
	} else {
		SetPageUptodate(pg);
		ClearPageError(pg);
	}

	flush_dcache_page(pg);
	kunmap(pg);

	D2(printk(KERN_DEBUG "readpage finished\n"));
	return ret;
}

int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg)
{
	int ret = jffs2_do_readpage_nolock(inode, pg);
	unlock_page(pg);
	return ret;
}


static int jffs2_readpage (struct file *filp, struct page *pg)
{
	struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host);
	int ret;

	mutex_lock(&f->sem);
	ret = jffs2_do_readpage_unlock(pg->mapping->host, pg);
	mutex_unlock(&f->sem);
	return ret;
}

static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned flags,
			struct page **pagep, void **fsdata)
{
	struct page *pg;
	struct inode *inode = mapping->host;
	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
	uint32_t pageofs = index << PAGE_CACHE_SHIFT;
	int ret = 0;

	pg = grab_cache_page_write_begin(mapping, index, flags);
	if (!pg)
		return -ENOMEM;
	*pagep = pg;

	D1(printk(KERN_DEBUG "jffs2_write_begin()\n"));

	if (pageofs > inode->i_size) {
		/* Make new hole frag from old EOF to new page */
		struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
		struct jffs2_raw_inode ri;
		struct jffs2_full_dnode *fn;
		uint32_t alloc_len;

		D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
			  (unsigned int)inode->i_size, pageofs));

		ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
					  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
		if (ret)
			goto out_page;

		mutex_lock(&f->sem);
		memset(&ri, 0, sizeof(ri));

		ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
		ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
		ri.totlen = cpu_to_je32(sizeof(ri));
		ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));

		ri.ino = cpu_to_je32(f->inocache->ino);
		ri.version = cpu_to_je32(++f->highest_version);
		ri.mode = cpu_to_jemode(inode->i_mode);
		ri.uid = cpu_to_je16(inode->i_uid);
		ri.gid = cpu_to_je16(inode->i_gid);
		ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));
		ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds());
		ri.offset = cpu_to_je32(inode->i_size);
		ri.dsize = cpu_to_je32(pageofs - inode->i_size);
		ri.csize = cpu_to_je32(0);
		ri.compr = JFFS2_COMPR_ZERO;
		ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
		ri.data_crc = cpu_to_je32(0);

		fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL);

		if (IS_ERR(fn)) {
			ret = PTR_ERR(fn);
			jffs2_complete_reservation(c);
			mutex_unlock(&f->sem);
			goto out_page;
		}
		ret = jffs2_add_full_dnode_to_inode(c, f, fn);
		if (f->metadata) {
			jffs2_mark_node_obsolete(c, f->metadata->raw);
			jffs2_free_full_dnode(f->metadata);
			f->metadata = NULL;
		}
		if (ret) {
			D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n", ret));
			jffs2_mark_node_obsolete(c, fn->raw);
			jffs2_free_full_dnode(fn);
			jffs2_complete_reservation(c);
			mutex_unlock(&f->sem);
			goto out_page;
		}
		jffs2_complete_reservation(c);
		inode->i_size = pageofs;
		mutex_unlock(&f->sem);
	}

	/*
	 * Read in the page if it wasn't already present. Cannot optimize away
	 * the whole page write case until jffs2_write_end can handle the
	 * case of a short-copy.
	 */
	if (!PageUptodate(pg)) {
		mutex_lock(&f->sem);
		ret = jffs2_do_readpage_nolock(inode, pg);
		mutex_unlock(&f->sem);
		if (ret)
			goto out_page;
	}
	D1(printk(KERN_DEBUG "end write_begin(). pg->flags %lx\n", pg->flags));
	return ret;

out_page:
	unlock_page(pg);
	page_cache_release(pg);
	return ret;
}

static int jffs2_write_end(struct file *filp, struct address_space *mapping,
			loff_t pos, unsigned len, unsigned copied,
			struct page *pg, void *fsdata)
{
	/* Actually commit the write from the page cache page we're looking at.
	 * For now, we write the full page out each time. It sucks, but it's simple
	 */
	struct inode *inode = mapping->host;
	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
	struct jffs2_raw_inode *ri;
	unsigned start = pos & (PAGE_CACHE_SIZE - 1);
	unsigned end = start + copied;
	unsigned aligned_start = start & ~3;
	int ret = 0;
	uint32_t writtenlen = 0;

	D1(printk(KERN_DEBUG "jffs2_write_end(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n",
		  inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, pg->flags));

	/* We need to avoid deadlock with page_cache_read() in
	   jffs2_garbage_collect_pass(). So the page must be
	   up to date to prevent page_cache_read() from trying
	   to re-lock it. */
	BUG_ON(!PageUptodate(pg));

	if (end == PAGE_CACHE_SIZE) {
		/* When writing out the end of a page, write out the
		   _whole_ page. This helps to reduce the number of
		   nodes in files which have many short writes, like
		   syslog files. */
		aligned_start = 0;
	}

	ri = jffs2_alloc_raw_inode();

	if (!ri) {
		D1(printk(KERN_DEBUG "jffs2_write_end(): Allocation of raw inode failed\n"));
		unlock_page(pg);
		page_cache_release(pg);
		return -ENOMEM;
	}

	/* Set the fields that the generic jffs2_write_inode_range() code can't find */
	ri->ino = cpu_to_je32(inode->i_ino);
	ri->mode = cpu_to_jemode(inode->i_mode);
	ri->uid = cpu_to_je16(inode->i_uid);
	ri->gid = cpu_to_je16(inode->i_gid);
	ri->isize = cpu_to_je32((uint32_t)inode->i_size);
	ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds());

	/* In 2.4, it was already kmapped by generic_file_write(). Doesn't
	   hurt to do it again. The alternative is ifdefs, which are ugly. */
	kmap(pg);

	ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start,
				      (pg->index << PAGE_CACHE_SHIFT) + aligned_start,
				      end - aligned_start, &writtenlen);

	kunmap(pg);

	if (ret) {
		/* There was an error writing. */
		SetPageError(pg);
	}

	/* Adjust writtenlen for the padding we did, so we don't confuse our caller */
	writtenlen -= min(writtenlen, (start - aligned_start));

	if (writtenlen) {
		if (inode->i_size < pos + writtenlen) {
			inode->i_size = pos + writtenlen;
			inode->i_blocks = (inode->i_size + 511) >> 9;

			inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime));
		}
	}

	jffs2_free_raw_inode(ri);

	if (start+writtenlen < end) {
		/* generic_file_write has written more to the page cache than we've
		   actually written to the medium. Mark the page !Uptodate so that
		   it gets reread */
		D1(printk(KERN_DEBUG "jffs2_write_end(): Not all bytes written. Marking page !uptodate\n"));
		SetPageError(pg);
		ClearPageUptodate(pg);
	}

	D1(printk(KERN_DEBUG "jffs2_write_end() returning %d\n",
					writtenlen > 0 ? writtenlen : ret));
	unlock_page(pg);
	page_cache_release(pg);
	return writtenlen > 0 ? writtenlen : ret;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* JFFS2 -- Journalling Flash File System, Version 2.
	3	*
c00c310e	4	* Copyright © 2001-2007 Red Hat, Inc.
6088c058	5	* Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
1da177e4 LT	6	*
	7	* Created by David Woodhouse <dwmw2@infradead.org>
	8	*
	9	* For licensing information, see the file 'LICENCE' in this directory.
	10	*
1da177e4 LT	11	*/
1da177e4 LT	12
1da177e4	13	#include <linux/kernel.h>
1da177e4 LT	14	#include <linux/fs.h>
	15	#include <linux/time.h>
	16	#include <linux/pagemap.h>
	17	#include <linux/highmem.h>
	18	#include <linux/crc32.h>
	19	#include <linux/jffs2.h>
	20	#include "nodelist.h"
	21
205c109a NP	22	static int jffs2_write_end(struct file filp, struct address_space mapping,
	23	loff_t pos, unsigned len, unsigned copied,
	24	struct page pg, void fsdata);
	25	static int jffs2_write_begin(struct file filp, struct address_space mapping,
	26	loff_t pos, unsigned len, unsigned flags,
	27	struct page pagep, void fsdata);
1da177e4 LT	28	static int jffs2_readpage (struct file filp, struct page pg);
1da177e4 LT	29
7ea80859	30	int jffs2_fsync(struct file *filp, int datasync)
1da177e4	31	{
7ea80859	32	struct inode *inode = filp->f_mapping->host;
1da177e4 LT	33	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
	34
	35	/* Trigger GC to flush any pending writes for this inode */
	36	jffs2_flush_wbuf_gc(c, inode->i_ino);
182ec4ee TG	37
182ec4ee TG	38	return 0;
1da177e4 LT	39	}
1da177e4 LT	40
4b6f5d20	41	const struct file_operations jffs2_file_operations =
1da177e4 LT	42	{
	43	.llseek = generic_file_llseek,
	44	.open = generic_file_open,
543ade1f BP	45	.read = do_sync_read,
	46	.aio_read = generic_file_aio_read,
	47	.write = do_sync_write,
	48	.aio_write = generic_file_aio_write,
0533400b	49	.unlocked_ioctl=jffs2_ioctl,
1da177e4 LT	50	.mmap = generic_file_readonly_mmap,
1da177e4 LT	51	.fsync = jffs2_fsync,
5ffc4ef4	52	.splice_read = generic_file_splice_read,
1da177e4 LT	53	};
	54
	55	/* jffs2_file_inode_operations */
	56
92e1d5be	57	const struct inode_operations jffs2_file_inode_operations =
1da177e4	58	{
18f4c644	59	.check_acl = jffs2_check_acl,
aa98d7cf KK	60	.setattr = jffs2_setattr,
	61	.setxattr = jffs2_setxattr,
	62	.getxattr = jffs2_getxattr,
	63	.listxattr = jffs2_listxattr,
	64	.removexattr = jffs2_removexattr
1da177e4 LT	65	};
1da177e4 LT	66
f5e54d6e	67	const struct address_space_operations jffs2_file_address_operations =
1da177e4 LT	68	{
1da177e4 LT	69	.readpage = jffs2_readpage,
205c109a NP	70	.write_begin = jffs2_write_begin,
205c109a NP	71	.write_end = jffs2_write_end,
1da177e4 LT	72	};
	73
	74	static int jffs2_do_readpage_nolock (struct inode inode, struct page pg)
	75	{
	76	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
	77	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
	78	unsigned char *pg_buf;
	79	int ret;
	80
	81	D2(printk(KERN_DEBUG "jffs2_do_readpage_nolock(): ino #%lu, page at offset 0x%lx\n", inode->i_ino, pg->index << PAGE_CACHE_SHIFT));
	82
cd7619d6	83	BUG_ON(!PageLocked(pg));
1da177e4 LT	84
	85	pg_buf = kmap(pg);
	86	/* FIXME: Can kmap fail? */
	87
	88	ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE);
	89
	90	if (ret) {
	91	ClearPageUptodate(pg);
	92	SetPageError(pg);
	93	} else {
	94	SetPageUptodate(pg);
	95	ClearPageError(pg);
	96	}
	97
	98	flush_dcache_page(pg);
	99	kunmap(pg);
	100
	101	D2(printk(KERN_DEBUG "readpage finished\n"));
57ca7deb	102	return ret;
1da177e4 LT	103	}
	104
	105	int jffs2_do_readpage_unlock(struct inode inode, struct page pg)
	106	{
	107	int ret = jffs2_do_readpage_nolock(inode, pg);
	108	unlock_page(pg);
	109	return ret;
	110	}
	111
	112
	113	static int jffs2_readpage (struct file filp, struct page pg)
	114	{
	115	struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host);
	116	int ret;
182ec4ee	117
ced22070	118	mutex_lock(&f->sem);
1da177e4	119	ret = jffs2_do_readpage_unlock(pg->mapping->host, pg);
ced22070	120	mutex_unlock(&f->sem);
1da177e4 LT	121	return ret;
	122	}
	123
205c109a NP	124	static int jffs2_write_begin(struct file filp, struct address_space mapping,
	125	loff_t pos, unsigned len, unsigned flags,
	126	struct page pagep, void fsdata)
1da177e4	127	{
205c109a NP	128	struct page *pg;
205c109a NP	129	struct inode *inode = mapping->host;
1da177e4	130	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
205c109a	131	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
abe2f414	132	uint32_t pageofs = index << PAGE_CACHE_SHIFT;
1da177e4 LT	133	int ret = 0;
1da177e4 LT	134
54566b2c	135	pg = grab_cache_page_write_begin(mapping, index, flags);
205c109a NP	136	if (!pg)
	137	return -ENOMEM;
	138	*pagep = pg;
	139
	140	D1(printk(KERN_DEBUG "jffs2_write_begin()\n"));
1da177e4 LT	141
	142	if (pageofs > inode->i_size) {
	143	/* Make new hole frag from old EOF to new page */
	144	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
	145	struct jffs2_raw_inode ri;
	146	struct jffs2_full_dnode *fn;
9fe4854c	147	uint32_t alloc_len;
182ec4ee	148
1da177e4 LT	149	D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
	150	(unsigned int)inode->i_size, pageofs));
	151
9fe4854c DW	152	ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
9fe4854c DW	153	ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
1da177e4	154	if (ret)
205c109a	155	goto out_page;
1da177e4	156
ced22070	157	mutex_lock(&f->sem);
1da177e4 LT	158	memset(&ri, 0, sizeof(ri));
	159
	160	ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
	161	ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
	162	ri.totlen = cpu_to_je32(sizeof(ri));
	163	ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
	164
	165	ri.ino = cpu_to_je32(f->inocache->ino);
	166	ri.version = cpu_to_je32(++f->highest_version);
	167	ri.mode = cpu_to_jemode(inode->i_mode);
	168	ri.uid = cpu_to_je16(inode->i_uid);
	169	ri.gid = cpu_to_je16(inode->i_gid);
	170	ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));
	171	ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds());
	172	ri.offset = cpu_to_je32(inode->i_size);
	173	ri.dsize = cpu_to_je32(pageofs - inode->i_size);
	174	ri.csize = cpu_to_je32(0);
	175	ri.compr = JFFS2_COMPR_ZERO;
	176	ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
	177	ri.data_crc = cpu_to_je32(0);
182ec4ee	178
9fe4854c	179	fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL);
1da177e4 LT	180
	181	if (IS_ERR(fn)) {
	182	ret = PTR_ERR(fn);
	183	jffs2_complete_reservation(c);
ced22070	184	mutex_unlock(&f->sem);
205c109a	185	goto out_page;
1da177e4 LT	186	}
	187	ret = jffs2_add_full_dnode_to_inode(c, f, fn);
	188	if (f->metadata) {
	189	jffs2_mark_node_obsolete(c, f->metadata->raw);
	190	jffs2_free_full_dnode(f->metadata);
	191	f->metadata = NULL;
	192	}
	193	if (ret) {
205c109a	194	D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n", ret));
1da177e4 LT	195	jffs2_mark_node_obsolete(c, fn->raw);
	196	jffs2_free_full_dnode(fn);
	197	jffs2_complete_reservation(c);
ced22070	198	mutex_unlock(&f->sem);
205c109a	199	goto out_page;
1da177e4 LT	200	}
	201	jffs2_complete_reservation(c);
	202	inode->i_size = pageofs;
ced22070	203	mutex_unlock(&f->sem);
1da177e4	204	}
182ec4ee	205
205c109a NP	206	/*
	207	* Read in the page if it wasn't already present. Cannot optimize away
	208	* the whole page write case until jffs2_write_end can handle the
	209	* case of a short-copy.
	210	*/
	211	if (!PageUptodate(pg)) {
ced22070	212	mutex_lock(&f->sem);
1da177e4	213	ret = jffs2_do_readpage_nolock(inode, pg);
ced22070	214	mutex_unlock(&f->sem);
205c109a NP	215	if (ret)
205c109a NP	216	goto out_page;
1da177e4	217	}
205c109a NP	218	D1(printk(KERN_DEBUG "end write_begin(). pg->flags %lx\n", pg->flags));
	219	return ret;
	220
	221	out_page:
	222	unlock_page(pg);
	223	page_cache_release(pg);
1da177e4 LT	224	return ret;
	225	}
	226
205c109a NP	227	static int jffs2_write_end(struct file filp, struct address_space mapping,
	228	loff_t pos, unsigned len, unsigned copied,
	229	struct page pg, void fsdata)
1da177e4 LT	230	{
	231	/* Actually commit the write from the page cache page we're looking at.
	232	* For now, we write the full page out each time. It sucks, but it's simple
	233	*/
205c109a	234	struct inode *inode = mapping->host;
1da177e4 LT	235	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
	236	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
	237	struct jffs2_raw_inode *ri;
205c109a NP	238	unsigned start = pos & (PAGE_CACHE_SIZE - 1);
205c109a NP	239	unsigned end = start + copied;
1da177e4 LT	240	unsigned aligned_start = start & ~3;
	241	int ret = 0;
	242	uint32_t writtenlen = 0;
	243
205c109a	244	D1(printk(KERN_DEBUG "jffs2_write_end(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n",
1da177e4 LT	245	inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, pg->flags));
1da177e4 LT	246
205c109a NP	247	/* We need to avoid deadlock with page_cache_read() in
	248	jffs2_garbage_collect_pass(). So the page must be
	249	up to date to prevent page_cache_read() from trying
	250	to re-lock it. */
	251	BUG_ON(!PageUptodate(pg));
	252
cf5eba53	253	if (end == PAGE_CACHE_SIZE) {
205c109a NP	254	/* When writing out the end of a page, write out the
	255	_whole_ page. This helps to reduce the number of
	256	nodes in files which have many short writes, like
	257	syslog files. */
2a754b51	258	aligned_start = 0;
1da177e4 LT	259	}
	260
	261	ri = jffs2_alloc_raw_inode();
	262
	263	if (!ri) {
205c109a NP	264	D1(printk(KERN_DEBUG "jffs2_write_end(): Allocation of raw inode failed\n"));
	265	unlock_page(pg);
	266	page_cache_release(pg);
1da177e4 LT	267	return -ENOMEM;
	268	}
	269
	270	/* Set the fields that the generic jffs2_write_inode_range() code can't find */
	271	ri->ino = cpu_to_je32(inode->i_ino);
	272	ri->mode = cpu_to_jemode(inode->i_mode);
	273	ri->uid = cpu_to_je16(inode->i_uid);
	274	ri->gid = cpu_to_je16(inode->i_gid);
	275	ri->isize = cpu_to_je32((uint32_t)inode->i_size);
	276	ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds());
	277
	278	/* In 2.4, it was already kmapped by generic_file_write(). Doesn't
	279	hurt to do it again. The alternative is ifdefs, which are ugly. */
	280	kmap(pg);
	281
	282	ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start,
	283	(pg->index << PAGE_CACHE_SHIFT) + aligned_start,
	284	end - aligned_start, &writtenlen);
	285
	286	kunmap(pg);
	287
	288	if (ret) {
	289	/* There was an error writing. */
	290	SetPageError(pg);
	291	}
182ec4ee	292
1da177e4	293	/* Adjust writtenlen for the padding we did, so we don't confuse our caller */
2a754b51	294	writtenlen -= min(writtenlen, (start - aligned_start));
1da177e4 LT	295
1da177e4 LT	296	if (writtenlen) {
2a754b51 NP	297	if (inode->i_size < pos + writtenlen) {
2a754b51 NP	298	inode->i_size = pos + writtenlen;
1da177e4	299	inode->i_blocks = (inode->i_size + 511) >> 9;
182ec4ee	300
1da177e4 LT	301	inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime));
	302	}
	303	}
	304
	305	jffs2_free_raw_inode(ri);
	306
	307	if (start+writtenlen < end) {
	308	/* generic_file_write has written more to the page cache than we've
182ec4ee	309	actually written to the medium. Mark the page !Uptodate so that
1da177e4	310	it gets reread */
205c109a	311	D1(printk(KERN_DEBUG "jffs2_write_end(): Not all bytes written. Marking page !uptodate\n"));
1da177e4 LT	312	SetPageError(pg);
	313	ClearPageUptodate(pg);
	314	}
	315
205c109a NP	316	D1(printk(KERN_DEBUG "jffs2_write_end() returning %d\n",
	317	writtenlen > 0 ? writtenlen : ret));
	318	unlock_page(pg);
	319	page_cache_release(pg);
	320	return writtenlen > 0 ? writtenlen : ret;
1da177e4	321	}