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v3.5.6
  1/*
  2 * JFFS2 -- Journalling Flash File System, Version 2.
  3 *
  4 * Copyright © 2001-2007 Red Hat, Inc.
  5 * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
  6 *
  7 * Created by David Woodhouse <dwmw2@infradead.org>
  8 *
  9 * For licensing information, see the file 'LICENCE' in this directory.
 10 *
 11 */
 12
 13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 14
 15#include <linux/kernel.h>
 16#include <linux/fs.h>
 17#include <linux/time.h>
 18#include <linux/pagemap.h>
 19#include <linux/highmem.h>
 20#include <linux/crc32.h>
 21#include <linux/jffs2.h>
 22#include "nodelist.h"
 23
 24static int jffs2_write_end(struct file *filp, struct address_space *mapping,
 25			loff_t pos, unsigned len, unsigned copied,
 26			struct page *pg, void *fsdata);
 27static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
 28			loff_t pos, unsigned len, unsigned flags,
 29			struct page **pagep, void **fsdata);
 30static int jffs2_readpage (struct file *filp, struct page *pg);
 31
 32int jffs2_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
 33{
 34	struct inode *inode = filp->f_mapping->host;
 35	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
 36	int ret;
 37
 38	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
 39	if (ret)
 40		return ret;
 41
 42	mutex_lock(&inode->i_mutex);
 43	/* Trigger GC to flush any pending writes for this inode */
 44	jffs2_flush_wbuf_gc(c, inode->i_ino);
 45	mutex_unlock(&inode->i_mutex);
 46
 47	return 0;
 48}
 49
 50const struct file_operations jffs2_file_operations =
 51{
 52	.llseek =	generic_file_llseek,
 53	.open =		generic_file_open,
 54 	.read =		do_sync_read,
 55 	.aio_read =	generic_file_aio_read,
 56 	.write =	do_sync_write,
 57 	.aio_write =	generic_file_aio_write,
 58	.unlocked_ioctl=jffs2_ioctl,
 59	.mmap =		generic_file_readonly_mmap,
 60	.fsync =	jffs2_fsync,
 61	.splice_read =	generic_file_splice_read,
 
 62};
 63
 64/* jffs2_file_inode_operations */
 65
 66const struct inode_operations jffs2_file_inode_operations =
 67{
 68	.get_acl =	jffs2_get_acl,
 
 69	.setattr =	jffs2_setattr,
 70	.setxattr =	jffs2_setxattr,
 71	.getxattr =	jffs2_getxattr,
 72	.listxattr =	jffs2_listxattr,
 73	.removexattr =	jffs2_removexattr
 74};
 75
 76const struct address_space_operations jffs2_file_address_operations =
 77{
 78	.readpage =	jffs2_readpage,
 79	.write_begin =	jffs2_write_begin,
 80	.write_end =	jffs2_write_end,
 81};
 82
 83static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg)
 84{
 85	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
 86	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
 87	unsigned char *pg_buf;
 88	int ret;
 89
 90	jffs2_dbg(2, "%s(): ino #%lu, page at offset 0x%lx\n",
 91		  __func__, inode->i_ino, pg->index << PAGE_CACHE_SHIFT);
 92
 93	BUG_ON(!PageLocked(pg));
 94
 95	pg_buf = kmap(pg);
 96	/* FIXME: Can kmap fail? */
 97
 98	ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE);
 
 99
100	if (ret) {
101		ClearPageUptodate(pg);
102		SetPageError(pg);
103	} else {
104		SetPageUptodate(pg);
105		ClearPageError(pg);
106	}
107
108	flush_dcache_page(pg);
109	kunmap(pg);
110
111	jffs2_dbg(2, "readpage finished\n");
112	return ret;
113}
114
115int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg)
116{
117	int ret = jffs2_do_readpage_nolock(inode, pg);
118	unlock_page(pg);
119	return ret;
120}
121
122
123static int jffs2_readpage (struct file *filp, struct page *pg)
124{
125	struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host);
126	int ret;
127
128	mutex_lock(&f->sem);
129	ret = jffs2_do_readpage_unlock(pg->mapping->host, pg);
130	mutex_unlock(&f->sem);
131	return ret;
132}
133
134static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
135			loff_t pos, unsigned len, unsigned flags,
136			struct page **pagep, void **fsdata)
137{
138	struct page *pg;
139	struct inode *inode = mapping->host;
140	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
141	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
142	uint32_t pageofs = index << PAGE_CACHE_SHIFT;
 
143	int ret = 0;
144
145	pg = grab_cache_page_write_begin(mapping, index, flags);
146	if (!pg)
147		return -ENOMEM;
148	*pagep = pg;
149
150	jffs2_dbg(1, "%s()\n", __func__);
151
152	if (pageofs > inode->i_size) {
153		/* Make new hole frag from old EOF to new page */
154		struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
155		struct jffs2_raw_inode ri;
156		struct jffs2_full_dnode *fn;
157		uint32_t alloc_len;
158
159		jffs2_dbg(1, "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
160			  (unsigned int)inode->i_size, pageofs);
161
162		ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
163					  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
164		if (ret)
165			goto out_page;
166
167		mutex_lock(&f->sem);
168		memset(&ri, 0, sizeof(ri));
169
170		ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
171		ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
172		ri.totlen = cpu_to_je32(sizeof(ri));
173		ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
174
175		ri.ino = cpu_to_je32(f->inocache->ino);
176		ri.version = cpu_to_je32(++f->highest_version);
177		ri.mode = cpu_to_jemode(inode->i_mode);
178		ri.uid = cpu_to_je16(inode->i_uid);
179		ri.gid = cpu_to_je16(inode->i_gid);
180		ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));
181		ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds());
182		ri.offset = cpu_to_je32(inode->i_size);
183		ri.dsize = cpu_to_je32(pageofs - inode->i_size);
184		ri.csize = cpu_to_je32(0);
185		ri.compr = JFFS2_COMPR_ZERO;
186		ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
187		ri.data_crc = cpu_to_je32(0);
188
189		fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL);
190
191		if (IS_ERR(fn)) {
192			ret = PTR_ERR(fn);
193			jffs2_complete_reservation(c);
194			mutex_unlock(&f->sem);
195			goto out_page;
196		}
197		ret = jffs2_add_full_dnode_to_inode(c, f, fn);
198		if (f->metadata) {
199			jffs2_mark_node_obsolete(c, f->metadata->raw);
200			jffs2_free_full_dnode(f->metadata);
201			f->metadata = NULL;
202		}
203		if (ret) {
204			jffs2_dbg(1, "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n",
205				  ret);
206			jffs2_mark_node_obsolete(c, fn->raw);
207			jffs2_free_full_dnode(fn);
208			jffs2_complete_reservation(c);
209			mutex_unlock(&f->sem);
210			goto out_page;
211		}
212		jffs2_complete_reservation(c);
213		inode->i_size = pageofs;
214		mutex_unlock(&f->sem);
215	}
216
217	/*
 
 
 
 
 
 
 
 
 
 
 
 
 
218	 * Read in the page if it wasn't already present. Cannot optimize away
219	 * the whole page write case until jffs2_write_end can handle the
220	 * case of a short-copy.
221	 */
222	if (!PageUptodate(pg)) {
223		mutex_lock(&f->sem);
224		ret = jffs2_do_readpage_nolock(inode, pg);
225		mutex_unlock(&f->sem);
226		if (ret)
227			goto out_page;
 
 
 
228	}
229	jffs2_dbg(1, "end write_begin(). pg->flags %lx\n", pg->flags);
230	return ret;
231
232out_page:
233	unlock_page(pg);
234	page_cache_release(pg);
235	return ret;
236}
237
238static int jffs2_write_end(struct file *filp, struct address_space *mapping,
239			loff_t pos, unsigned len, unsigned copied,
240			struct page *pg, void *fsdata)
241{
242	/* Actually commit the write from the page cache page we're looking at.
243	 * For now, we write the full page out each time. It sucks, but it's simple
244	 */
245	struct inode *inode = mapping->host;
246	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
247	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
248	struct jffs2_raw_inode *ri;
249	unsigned start = pos & (PAGE_CACHE_SIZE - 1);
250	unsigned end = start + copied;
251	unsigned aligned_start = start & ~3;
252	int ret = 0;
253	uint32_t writtenlen = 0;
254
255	jffs2_dbg(1, "%s(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n",
256		  __func__, inode->i_ino, pg->index << PAGE_CACHE_SHIFT,
257		  start, end, pg->flags);
258
259	/* We need to avoid deadlock with page_cache_read() in
260	   jffs2_garbage_collect_pass(). So the page must be
261	   up to date to prevent page_cache_read() from trying
262	   to re-lock it. */
263	BUG_ON(!PageUptodate(pg));
264
265	if (end == PAGE_CACHE_SIZE) {
266		/* When writing out the end of a page, write out the
267		   _whole_ page. This helps to reduce the number of
268		   nodes in files which have many short writes, like
269		   syslog files. */
270		aligned_start = 0;
271	}
272
273	ri = jffs2_alloc_raw_inode();
274
275	if (!ri) {
276		jffs2_dbg(1, "%s(): Allocation of raw inode failed\n",
277			  __func__);
278		unlock_page(pg);
279		page_cache_release(pg);
280		return -ENOMEM;
281	}
282
283	/* Set the fields that the generic jffs2_write_inode_range() code can't find */
284	ri->ino = cpu_to_je32(inode->i_ino);
285	ri->mode = cpu_to_jemode(inode->i_mode);
286	ri->uid = cpu_to_je16(inode->i_uid);
287	ri->gid = cpu_to_je16(inode->i_gid);
288	ri->isize = cpu_to_je32((uint32_t)inode->i_size);
289	ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds());
290
291	/* In 2.4, it was already kmapped by generic_file_write(). Doesn't
292	   hurt to do it again. The alternative is ifdefs, which are ugly. */
293	kmap(pg);
294
295	ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start,
296				      (pg->index << PAGE_CACHE_SHIFT) + aligned_start,
297				      end - aligned_start, &writtenlen);
298
299	kunmap(pg);
300
301	if (ret) {
302		/* There was an error writing. */
303		SetPageError(pg);
304	}
305
306	/* Adjust writtenlen for the padding we did, so we don't confuse our caller */
307	writtenlen -= min(writtenlen, (start - aligned_start));
308
309	if (writtenlen) {
310		if (inode->i_size < pos + writtenlen) {
311			inode->i_size = pos + writtenlen;
312			inode->i_blocks = (inode->i_size + 511) >> 9;
313
314			inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime));
315		}
316	}
317
318	jffs2_free_raw_inode(ri);
319
320	if (start+writtenlen < end) {
321		/* generic_file_write has written more to the page cache than we've
322		   actually written to the medium. Mark the page !Uptodate so that
323		   it gets reread */
324		jffs2_dbg(1, "%s(): Not all bytes written. Marking page !uptodate\n",
325			__func__);
326		SetPageError(pg);
327		ClearPageUptodate(pg);
328	}
329
330	jffs2_dbg(1, "%s() returning %d\n",
331		  __func__, writtenlen > 0 ? writtenlen : ret);
332	unlock_page(pg);
333	page_cache_release(pg);
334	return writtenlen > 0 ? writtenlen : ret;
335}
v6.2
  1/*
  2 * JFFS2 -- Journalling Flash File System, Version 2.
  3 *
  4 * Copyright © 2001-2007 Red Hat, Inc.
  5 * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
  6 *
  7 * Created by David Woodhouse <dwmw2@infradead.org>
  8 *
  9 * For licensing information, see the file 'LICENCE' in this directory.
 10 *
 11 */
 12
 13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 14
 15#include <linux/kernel.h>
 16#include <linux/fs.h>
 17#include <linux/time.h>
 18#include <linux/pagemap.h>
 19#include <linux/highmem.h>
 20#include <linux/crc32.h>
 21#include <linux/jffs2.h>
 22#include "nodelist.h"
 23
 24static int jffs2_write_end(struct file *filp, struct address_space *mapping,
 25			loff_t pos, unsigned len, unsigned copied,
 26			struct page *pg, void *fsdata);
 27static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
 28			loff_t pos, unsigned len,
 29			struct page **pagep, void **fsdata);
 30static int jffs2_read_folio(struct file *filp, struct folio *folio);
 31
 32int jffs2_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
 33{
 34	struct inode *inode = filp->f_mapping->host;
 35	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
 36	int ret;
 37
 38	ret = file_write_and_wait_range(filp, start, end);
 39	if (ret)
 40		return ret;
 41
 42	inode_lock(inode);
 43	/* Trigger GC to flush any pending writes for this inode */
 44	jffs2_flush_wbuf_gc(c, inode->i_ino);
 45	inode_unlock(inode);
 46
 47	return 0;
 48}
 49
 50const struct file_operations jffs2_file_operations =
 51{
 52	.llseek =	generic_file_llseek,
 53	.open =		generic_file_open,
 54 	.read_iter =	generic_file_read_iter,
 55 	.write_iter =	generic_file_write_iter,
 
 
 56	.unlocked_ioctl=jffs2_ioctl,
 57	.mmap =		generic_file_readonly_mmap,
 58	.fsync =	jffs2_fsync,
 59	.splice_read =	generic_file_splice_read,
 60	.splice_write = iter_file_splice_write,
 61};
 62
 63/* jffs2_file_inode_operations */
 64
 65const struct inode_operations jffs2_file_inode_operations =
 66{
 67	.get_inode_acl =	jffs2_get_acl,
 68	.set_acl =	jffs2_set_acl,
 69	.setattr =	jffs2_setattr,
 
 
 70	.listxattr =	jffs2_listxattr,
 
 71};
 72
 73const struct address_space_operations jffs2_file_address_operations =
 74{
 75	.read_folio =	jffs2_read_folio,
 76	.write_begin =	jffs2_write_begin,
 77	.write_end =	jffs2_write_end,
 78};
 79
 80static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg)
 81{
 82	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
 83	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
 84	unsigned char *pg_buf;
 85	int ret;
 86
 87	jffs2_dbg(2, "%s(): ino #%lu, page at offset 0x%lx\n",
 88		  __func__, inode->i_ino, pg->index << PAGE_SHIFT);
 89
 90	BUG_ON(!PageLocked(pg));
 91
 92	pg_buf = kmap(pg);
 93	/* FIXME: Can kmap fail? */
 94
 95	ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_SHIFT,
 96				     PAGE_SIZE);
 97
 98	if (ret) {
 99		ClearPageUptodate(pg);
100		SetPageError(pg);
101	} else {
102		SetPageUptodate(pg);
103		ClearPageError(pg);
104	}
105
106	flush_dcache_page(pg);
107	kunmap(pg);
108
109	jffs2_dbg(2, "readpage finished\n");
110	return ret;
111}
112
113int __jffs2_read_folio(struct file *file, struct folio *folio)
114{
115	int ret = jffs2_do_readpage_nolock(folio->mapping->host, &folio->page);
116	folio_unlock(folio);
117	return ret;
118}
119
120static int jffs2_read_folio(struct file *file, struct folio *folio)
 
121{
122	struct jffs2_inode_info *f = JFFS2_INODE_INFO(folio->mapping->host);
123	int ret;
124
125	mutex_lock(&f->sem);
126	ret = __jffs2_read_folio(file, folio);
127	mutex_unlock(&f->sem);
128	return ret;
129}
130
131static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
132			loff_t pos, unsigned len,
133			struct page **pagep, void **fsdata)
134{
135	struct page *pg;
136	struct inode *inode = mapping->host;
137	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
138	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
139	pgoff_t index = pos >> PAGE_SHIFT;
140	uint32_t pageofs = index << PAGE_SHIFT;
141	int ret = 0;
142
 
 
 
 
 
143	jffs2_dbg(1, "%s()\n", __func__);
144
145	if (pageofs > inode->i_size) {
146		/* Make new hole frag from old EOF to new page */
 
147		struct jffs2_raw_inode ri;
148		struct jffs2_full_dnode *fn;
149		uint32_t alloc_len;
150
151		jffs2_dbg(1, "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
152			  (unsigned int)inode->i_size, pageofs);
153
154		ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
155					  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
156		if (ret)
157			goto out_err;
158
159		mutex_lock(&f->sem);
160		memset(&ri, 0, sizeof(ri));
161
162		ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
163		ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
164		ri.totlen = cpu_to_je32(sizeof(ri));
165		ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
166
167		ri.ino = cpu_to_je32(f->inocache->ino);
168		ri.version = cpu_to_je32(++f->highest_version);
169		ri.mode = cpu_to_jemode(inode->i_mode);
170		ri.uid = cpu_to_je16(i_uid_read(inode));
171		ri.gid = cpu_to_je16(i_gid_read(inode));
172		ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));
173		ri.atime = ri.ctime = ri.mtime = cpu_to_je32(JFFS2_NOW());
174		ri.offset = cpu_to_je32(inode->i_size);
175		ri.dsize = cpu_to_je32(pageofs - inode->i_size);
176		ri.csize = cpu_to_je32(0);
177		ri.compr = JFFS2_COMPR_ZERO;
178		ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
179		ri.data_crc = cpu_to_je32(0);
180
181		fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL);
182
183		if (IS_ERR(fn)) {
184			ret = PTR_ERR(fn);
185			jffs2_complete_reservation(c);
186			mutex_unlock(&f->sem);
187			goto out_err;
188		}
189		ret = jffs2_add_full_dnode_to_inode(c, f, fn);
190		if (f->metadata) {
191			jffs2_mark_node_obsolete(c, f->metadata->raw);
192			jffs2_free_full_dnode(f->metadata);
193			f->metadata = NULL;
194		}
195		if (ret) {
196			jffs2_dbg(1, "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n",
197				  ret);
198			jffs2_mark_node_obsolete(c, fn->raw);
199			jffs2_free_full_dnode(fn);
200			jffs2_complete_reservation(c);
201			mutex_unlock(&f->sem);
202			goto out_err;
203		}
204		jffs2_complete_reservation(c);
205		inode->i_size = pageofs;
206		mutex_unlock(&f->sem);
207	}
208
209	/*
210	 * While getting a page and reading data in, lock c->alloc_sem until
211	 * the page is Uptodate. Otherwise GC task may attempt to read the same
212	 * page in read_cache_page(), which causes a deadlock.
213	 */
214	mutex_lock(&c->alloc_sem);
215	pg = grab_cache_page_write_begin(mapping, index);
216	if (!pg) {
217		ret = -ENOMEM;
218		goto release_sem;
219	}
220	*pagep = pg;
221
222	/*
223	 * Read in the page if it wasn't already present. Cannot optimize away
224	 * the whole page write case until jffs2_write_end can handle the
225	 * case of a short-copy.
226	 */
227	if (!PageUptodate(pg)) {
228		mutex_lock(&f->sem);
229		ret = jffs2_do_readpage_nolock(inode, pg);
230		mutex_unlock(&f->sem);
231		if (ret) {
232			unlock_page(pg);
233			put_page(pg);
234			goto release_sem;
235		}
236	}
237	jffs2_dbg(1, "end write_begin(). pg->flags %lx\n", pg->flags);
 
238
239release_sem:
240	mutex_unlock(&c->alloc_sem);
241out_err:
242	return ret;
243}
244
245static int jffs2_write_end(struct file *filp, struct address_space *mapping,
246			loff_t pos, unsigned len, unsigned copied,
247			struct page *pg, void *fsdata)
248{
249	/* Actually commit the write from the page cache page we're looking at.
250	 * For now, we write the full page out each time. It sucks, but it's simple
251	 */
252	struct inode *inode = mapping->host;
253	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
254	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
255	struct jffs2_raw_inode *ri;
256	unsigned start = pos & (PAGE_SIZE - 1);
257	unsigned end = start + copied;
258	unsigned aligned_start = start & ~3;
259	int ret = 0;
260	uint32_t writtenlen = 0;
261
262	jffs2_dbg(1, "%s(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n",
263		  __func__, inode->i_ino, pg->index << PAGE_SHIFT,
264		  start, end, pg->flags);
265
266	/* We need to avoid deadlock with page_cache_read() in
267	   jffs2_garbage_collect_pass(). So the page must be
268	   up to date to prevent page_cache_read() from trying
269	   to re-lock it. */
270	BUG_ON(!PageUptodate(pg));
271
272	if (end == PAGE_SIZE) {
273		/* When writing out the end of a page, write out the
274		   _whole_ page. This helps to reduce the number of
275		   nodes in files which have many short writes, like
276		   syslog files. */
277		aligned_start = 0;
278	}
279
280	ri = jffs2_alloc_raw_inode();
281
282	if (!ri) {
283		jffs2_dbg(1, "%s(): Allocation of raw inode failed\n",
284			  __func__);
285		unlock_page(pg);
286		put_page(pg);
287		return -ENOMEM;
288	}
289
290	/* Set the fields that the generic jffs2_write_inode_range() code can't find */
291	ri->ino = cpu_to_je32(inode->i_ino);
292	ri->mode = cpu_to_jemode(inode->i_mode);
293	ri->uid = cpu_to_je16(i_uid_read(inode));
294	ri->gid = cpu_to_je16(i_gid_read(inode));
295	ri->isize = cpu_to_je32((uint32_t)inode->i_size);
296	ri->atime = ri->ctime = ri->mtime = cpu_to_je32(JFFS2_NOW());
297
298	/* In 2.4, it was already kmapped by generic_file_write(). Doesn't
299	   hurt to do it again. The alternative is ifdefs, which are ugly. */
300	kmap(pg);
301
302	ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start,
303				      (pg->index << PAGE_SHIFT) + aligned_start,
304				      end - aligned_start, &writtenlen);
305
306	kunmap(pg);
307
308	if (ret) {
309		/* There was an error writing. */
310		SetPageError(pg);
311	}
312
313	/* Adjust writtenlen for the padding we did, so we don't confuse our caller */
314	writtenlen -= min(writtenlen, (start - aligned_start));
315
316	if (writtenlen) {
317		if (inode->i_size < pos + writtenlen) {
318			inode->i_size = pos + writtenlen;
319			inode->i_blocks = (inode->i_size + 511) >> 9;
320
321			inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime));
322		}
323	}
324
325	jffs2_free_raw_inode(ri);
326
327	if (start+writtenlen < end) {
328		/* generic_file_write has written more to the page cache than we've
329		   actually written to the medium. Mark the page !Uptodate so that
330		   it gets reread */
331		jffs2_dbg(1, "%s(): Not all bytes written. Marking page !uptodate\n",
332			__func__);
333		SetPageError(pg);
334		ClearPageUptodate(pg);
335	}
336
337	jffs2_dbg(1, "%s() returning %d\n",
338		  __func__, writtenlen > 0 ? writtenlen : ret);
339	unlock_page(pg);
340	put_page(pg);
341	return writtenlen > 0 ? writtenlen : ret;
342}