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v3.1
  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#include <linux/kernel.h>
 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
 22static 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);
 25static 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);
 28static int jffs2_readpage (struct file *filp, struct page *pg);
 29
 30int jffs2_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
 31{
 32	struct inode *inode = filp->f_mapping->host;
 33	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
 34	int ret;
 35
 36	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
 37	if (ret)
 38		return ret;
 39
 40	mutex_lock(&inode->i_mutex);
 41	/* Trigger GC to flush any pending writes for this inode */
 42	jffs2_flush_wbuf_gc(c, inode->i_ino);
 43	mutex_unlock(&inode->i_mutex);
 44
 45	return 0;
 46}
 47
 48const struct file_operations jffs2_file_operations =
 49{
 50	.llseek =	generic_file_llseek,
 51	.open =		generic_file_open,
 52 	.read =		do_sync_read,
 53 	.aio_read =	generic_file_aio_read,
 54 	.write =	do_sync_write,
 55 	.aio_write =	generic_file_aio_write,
 56	.unlocked_ioctl=jffs2_ioctl,
 57	.mmap =		generic_file_readonly_mmap,
 58	.fsync =	jffs2_fsync,
 59	.splice_read =	generic_file_splice_read,
 
 60};
 61
 62/* jffs2_file_inode_operations */
 63
 64const struct inode_operations jffs2_file_inode_operations =
 65{
 66	.get_acl =	jffs2_get_acl,
 
 67	.setattr =	jffs2_setattr,
 68	.setxattr =	jffs2_setxattr,
 69	.getxattr =	jffs2_getxattr,
 70	.listxattr =	jffs2_listxattr,
 71	.removexattr =	jffs2_removexattr
 72};
 73
 74const struct address_space_operations jffs2_file_address_operations =
 75{
 76	.readpage =	jffs2_readpage,
 77	.write_begin =	jffs2_write_begin,
 78	.write_end =	jffs2_write_end,
 79};
 80
 81static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg)
 82{
 83	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
 84	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
 85	unsigned char *pg_buf;
 86	int ret;
 87
 88	D2(printk(KERN_DEBUG "jffs2_do_readpage_nolock(): ino #%lu, page at offset 0x%lx\n", inode->i_ino, pg->index << PAGE_CACHE_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_CACHE_SHIFT, PAGE_CACHE_SIZE);
 
 
 
 96
 97	if (ret) {
 98		ClearPageUptodate(pg);
 99		SetPageError(pg);
100	} else {
101		SetPageUptodate(pg);
102		ClearPageError(pg);
103	}
104
105	flush_dcache_page(pg);
106	kunmap(pg);
107
108	D2(printk(KERN_DEBUG "readpage finished\n"));
109	return ret;
110}
111
112int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg)
113{
114	int ret = jffs2_do_readpage_nolock(inode, pg);
115	unlock_page(pg);
116	return ret;
117}
118
119
120static int jffs2_readpage (struct file *filp, struct page *pg)
121{
122	struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host);
123	int ret;
124
125	mutex_lock(&f->sem);
126	ret = jffs2_do_readpage_unlock(pg->mapping->host, pg);
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, unsigned flags,
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	pgoff_t index = pos >> PAGE_CACHE_SHIFT;
139	uint32_t pageofs = index << PAGE_CACHE_SHIFT;
140	int ret = 0;
141
142	pg = grab_cache_page_write_begin(mapping, index, flags);
143	if (!pg)
144		return -ENOMEM;
145	*pagep = pg;
146
147	D1(printk(KERN_DEBUG "jffs2_write_begin()\n"));
148
149	if (pageofs > inode->i_size) {
150		/* Make new hole frag from old EOF to new page */
151		struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
152		struct jffs2_raw_inode ri;
153		struct jffs2_full_dnode *fn;
154		uint32_t alloc_len;
155
156		D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
157			  (unsigned int)inode->i_size, pageofs));
158
159		ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
160					  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
161		if (ret)
162			goto out_page;
163
164		mutex_lock(&f->sem);
165		memset(&ri, 0, sizeof(ri));
166
167		ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
168		ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
169		ri.totlen = cpu_to_je32(sizeof(ri));
170		ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
171
172		ri.ino = cpu_to_je32(f->inocache->ino);
173		ri.version = cpu_to_je32(++f->highest_version);
174		ri.mode = cpu_to_jemode(inode->i_mode);
175		ri.uid = cpu_to_je16(inode->i_uid);
176		ri.gid = cpu_to_je16(inode->i_gid);
177		ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));
178		ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds());
179		ri.offset = cpu_to_je32(inode->i_size);
180		ri.dsize = cpu_to_je32(pageofs - inode->i_size);
181		ri.csize = cpu_to_je32(0);
182		ri.compr = JFFS2_COMPR_ZERO;
183		ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
184		ri.data_crc = cpu_to_je32(0);
185
186		fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL);
187
188		if (IS_ERR(fn)) {
189			ret = PTR_ERR(fn);
190			jffs2_complete_reservation(c);
191			mutex_unlock(&f->sem);
192			goto out_page;
193		}
194		ret = jffs2_add_full_dnode_to_inode(c, f, fn);
195		if (f->metadata) {
196			jffs2_mark_node_obsolete(c, f->metadata->raw);
197			jffs2_free_full_dnode(f->metadata);
198			f->metadata = NULL;
199		}
200		if (ret) {
201			D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n", ret));
 
202			jffs2_mark_node_obsolete(c, fn->raw);
203			jffs2_free_full_dnode(fn);
204			jffs2_complete_reservation(c);
205			mutex_unlock(&f->sem);
206			goto out_page;
207		}
208		jffs2_complete_reservation(c);
209		inode->i_size = pageofs;
210		mutex_unlock(&f->sem);
211	}
212
213	/*
214	 * Read in the page if it wasn't already present. Cannot optimize away
215	 * the whole page write case until jffs2_write_end can handle the
 
 
 
 
 
 
 
 
 
 
 
 
 
 
216	 * case of a short-copy.
217	 */
218	if (!PageUptodate(pg)) {
219		mutex_lock(&f->sem);
220		ret = jffs2_do_readpage_nolock(inode, pg);
221		mutex_unlock(&f->sem);
222		if (ret)
223			goto out_page;
 
 
 
224	}
225	D1(printk(KERN_DEBUG "end write_begin(). pg->flags %lx\n", pg->flags));
226	return ret;
227
228out_page:
229	unlock_page(pg);
230	page_cache_release(pg);
231	return ret;
232}
233
234static int jffs2_write_end(struct file *filp, struct address_space *mapping,
235			loff_t pos, unsigned len, unsigned copied,
236			struct page *pg, void *fsdata)
237{
238	/* Actually commit the write from the page cache page we're looking at.
239	 * For now, we write the full page out each time. It sucks, but it's simple
240	 */
241	struct inode *inode = mapping->host;
242	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
243	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
244	struct jffs2_raw_inode *ri;
245	unsigned start = pos & (PAGE_CACHE_SIZE - 1);
246	unsigned end = start + copied;
247	unsigned aligned_start = start & ~3;
248	int ret = 0;
249	uint32_t writtenlen = 0;
 
250
251	D1(printk(KERN_DEBUG "jffs2_write_end(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n",
252		  inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, pg->flags));
 
253
254	/* We need to avoid deadlock with page_cache_read() in
255	   jffs2_garbage_collect_pass(). So the page must be
256	   up to date to prevent page_cache_read() from trying
257	   to re-lock it. */
258	BUG_ON(!PageUptodate(pg));
259
260	if (end == PAGE_CACHE_SIZE) {
261		/* When writing out the end of a page, write out the
262		   _whole_ page. This helps to reduce the number of
263		   nodes in files which have many short writes, like
264		   syslog files. */
265		aligned_start = 0;
266	}
267
268	ri = jffs2_alloc_raw_inode();
269
270	if (!ri) {
271		D1(printk(KERN_DEBUG "jffs2_write_end(): Allocation of raw inode failed\n"));
272		unlock_page(pg);
273		page_cache_release(pg);
 
274		return -ENOMEM;
275	}
276
277	/* Set the fields that the generic jffs2_write_inode_range() code can't find */
278	ri->ino = cpu_to_je32(inode->i_ino);
279	ri->mode = cpu_to_jemode(inode->i_mode);
280	ri->uid = cpu_to_je16(inode->i_uid);
281	ri->gid = cpu_to_je16(inode->i_gid);
282	ri->isize = cpu_to_je32((uint32_t)inode->i_size);
283	ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds());
284
285	/* In 2.4, it was already kmapped by generic_file_write(). Doesn't
286	   hurt to do it again. The alternative is ifdefs, which are ugly. */
287	kmap(pg);
288
289	ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start,
290				      (pg->index << PAGE_CACHE_SHIFT) + aligned_start,
291				      end - aligned_start, &writtenlen);
 
292
293	kunmap(pg);
294
295	if (ret) {
296		/* There was an error writing. */
297		SetPageError(pg);
298	}
299
300	/* Adjust writtenlen for the padding we did, so we don't confuse our caller */
301	writtenlen -= min(writtenlen, (start - aligned_start));
302
303	if (writtenlen) {
304		if (inode->i_size < pos + writtenlen) {
305			inode->i_size = pos + writtenlen;
306			inode->i_blocks = (inode->i_size + 511) >> 9;
307
308			inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime));
 
309		}
310	}
311
312	jffs2_free_raw_inode(ri);
313
314	if (start+writtenlen < end) {
315		/* generic_file_write has written more to the page cache than we've
316		   actually written to the medium. Mark the page !Uptodate so that
317		   it gets reread */
318		D1(printk(KERN_DEBUG "jffs2_write_end(): Not all bytes written. Marking page !uptodate\n"));
319		SetPageError(pg);
320		ClearPageUptodate(pg);
321	}
322
323	D1(printk(KERN_DEBUG "jffs2_write_end() returning %d\n",
324					writtenlen > 0 ? writtenlen : ret));
325	unlock_page(pg);
326	page_cache_release(pg);
327	return writtenlen > 0 ? writtenlen : ret;
328}
v6.13.7
  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 folio *folio, void *fsdata);
 27static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
 28			loff_t pos, unsigned len,
 29			struct folio **foliop, 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 =	filemap_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 folio *folio)
 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 *kaddr;
 85	int ret;
 86
 87	jffs2_dbg(2, "%s(): ino #%lu, page at offset 0x%lx\n",
 88		  __func__, inode->i_ino, folio->index << PAGE_SHIFT);
 
 89
 90	BUG_ON(!folio_test_locked(folio));
 
 91
 92	kaddr = kmap_local_folio(folio, 0);
 93	ret = jffs2_read_inode_range(c, f, kaddr, folio->index << PAGE_SHIFT,
 94				     PAGE_SIZE);
 95	kunmap_local(kaddr);
 96
 97	if (!ret)
 98		folio_mark_uptodate(folio);
 
 
 
 
 
 99
100	flush_dcache_folio(folio);
 
101
102	jffs2_dbg(2, "readpage finished\n");
103	return ret;
104}
105
106int __jffs2_read_folio(struct file *file, struct folio *folio)
107{
108	int ret = jffs2_do_readpage_nolock(folio->mapping->host, folio);
109	folio_unlock(folio);
110	return ret;
111}
112
113static int jffs2_read_folio(struct file *file, struct folio *folio)
 
114{
115	struct jffs2_inode_info *f = JFFS2_INODE_INFO(folio->mapping->host);
116	int ret;
117
118	mutex_lock(&f->sem);
119	ret = __jffs2_read_folio(file, folio);
120	mutex_unlock(&f->sem);
121	return ret;
122}
123
124static int jffs2_write_begin(struct file *filp, struct address_space *mapping,
125			loff_t pos, unsigned len,
126			struct folio **foliop, void **fsdata)
127{
128	struct folio *folio;
129	struct inode *inode = mapping->host;
130	struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
131	struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
132	pgoff_t index = pos >> PAGE_SHIFT;
133	int ret = 0;
134
135	jffs2_dbg(1, "%s()\n", __func__);
 
 
 
 
 
136
137	if (pos > inode->i_size) {
138		/* Make new hole frag from old EOF to new position */
 
139		struct jffs2_raw_inode ri;
140		struct jffs2_full_dnode *fn;
141		uint32_t alloc_len;
142
143		jffs2_dbg(1, "Writing new hole frag 0x%x-0x%x between current EOF and new position\n",
144			  (unsigned int)inode->i_size, (uint32_t)pos);
145
146		ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
147					  ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
148		if (ret)
149			goto out_err;
150
151		mutex_lock(&f->sem);
152		memset(&ri, 0, sizeof(ri));
153
154		ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
155		ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
156		ri.totlen = cpu_to_je32(sizeof(ri));
157		ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
158
159		ri.ino = cpu_to_je32(f->inocache->ino);
160		ri.version = cpu_to_je32(++f->highest_version);
161		ri.mode = cpu_to_jemode(inode->i_mode);
162		ri.uid = cpu_to_je16(i_uid_read(inode));
163		ri.gid = cpu_to_je16(i_gid_read(inode));
164		ri.isize = cpu_to_je32((uint32_t)pos);
165		ri.atime = ri.ctime = ri.mtime = cpu_to_je32(JFFS2_NOW());
166		ri.offset = cpu_to_je32(inode->i_size);
167		ri.dsize = cpu_to_je32((uint32_t)pos - inode->i_size);
168		ri.csize = cpu_to_je32(0);
169		ri.compr = JFFS2_COMPR_ZERO;
170		ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
171		ri.data_crc = cpu_to_je32(0);
172
173		fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL);
174
175		if (IS_ERR(fn)) {
176			ret = PTR_ERR(fn);
177			jffs2_complete_reservation(c);
178			mutex_unlock(&f->sem);
179			goto out_err;
180		}
181		ret = jffs2_add_full_dnode_to_inode(c, f, fn);
182		if (f->metadata) {
183			jffs2_mark_node_obsolete(c, f->metadata->raw);
184			jffs2_free_full_dnode(f->metadata);
185			f->metadata = NULL;
186		}
187		if (ret) {
188			jffs2_dbg(1, "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n",
189				  ret);
190			jffs2_mark_node_obsolete(c, fn->raw);
191			jffs2_free_full_dnode(fn);
192			jffs2_complete_reservation(c);
193			mutex_unlock(&f->sem);
194			goto out_err;
195		}
196		jffs2_complete_reservation(c);
197		inode->i_size = pos;
198		mutex_unlock(&f->sem);
199	}
200
201	/*
202	 * While getting a page and reading data in, lock c->alloc_sem until
203	 * the page is Uptodate. Otherwise GC task may attempt to read the same
204	 * page in read_cache_page(), which causes a deadlock.
205	 */
206	mutex_lock(&c->alloc_sem);
207	folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN,
208			mapping_gfp_mask(mapping));
209	if (IS_ERR(folio)) {
210		ret = PTR_ERR(folio);
211		goto release_sem;
212	}
213	*foliop = folio;
214
215	/*
216	 * Read in the folio if it wasn't already present. Cannot optimize away
217	 * the whole folio write case until jffs2_write_end can handle the
218	 * case of a short-copy.
219	 */
220	if (!folio_test_uptodate(folio)) {
221		mutex_lock(&f->sem);
222		ret = jffs2_do_readpage_nolock(inode, folio);
223		mutex_unlock(&f->sem);
224		if (ret) {
225			folio_unlock(folio);
226			folio_put(folio);
227			goto release_sem;
228		}
229	}
230	jffs2_dbg(1, "end write_begin(). folio->flags %lx\n", folio->flags);
 
231
232release_sem:
233	mutex_unlock(&c->alloc_sem);
234out_err:
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 folio *folio, 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_SIZE - 1);
250	unsigned end = start + copied;
251	unsigned aligned_start = start & ~3;
252	int ret = 0;
253	uint32_t writtenlen = 0;
254	void *buf;
255
256	jffs2_dbg(1, "%s(): ino #%lu, page at 0x%llx, range %d-%d, flags %lx\n",
257		  __func__, inode->i_ino, folio_pos(folio),
258		  start, end, folio->flags);
259
260	/* We need to avoid deadlock with page_cache_read() in
261	   jffs2_garbage_collect_pass(). So the folio must be
262	   up to date to prevent page_cache_read() from trying
263	   to re-lock it. */
264	BUG_ON(!folio_test_uptodate(folio));
265
266	if (end == PAGE_SIZE) {
267		/* When writing out the end of a page, write out the
268		   _whole_ page. This helps to reduce the number of
269		   nodes in files which have many short writes, like
270		   syslog files. */
271		aligned_start = 0;
272	}
273
274	ri = jffs2_alloc_raw_inode();
275
276	if (!ri) {
277		jffs2_dbg(1, "%s(): Allocation of raw inode failed\n",
278			  __func__);
279		folio_unlock(folio);
280		folio_put(folio);
281		return -ENOMEM;
282	}
283
284	/* Set the fields that the generic jffs2_write_inode_range() code can't find */
285	ri->ino = cpu_to_je32(inode->i_ino);
286	ri->mode = cpu_to_jemode(inode->i_mode);
287	ri->uid = cpu_to_je16(i_uid_read(inode));
288	ri->gid = cpu_to_je16(i_gid_read(inode));
289	ri->isize = cpu_to_je32((uint32_t)inode->i_size);
290	ri->atime = ri->ctime = ri->mtime = cpu_to_je32(JFFS2_NOW());
291
292	buf = kmap_local_folio(folio, aligned_start);
293	ret = jffs2_write_inode_range(c, f, ri, buf,
294				      folio_pos(folio) + aligned_start,
 
 
 
295				      end - aligned_start, &writtenlen);
296	kunmap_local(buf);
297
298	if (ret)
299		mapping_set_error(mapping, ret);
 
 
 
 
300
301	/* Adjust writtenlen for the padding we did, so we don't confuse our caller */
302	writtenlen -= min(writtenlen, (start - aligned_start));
303
304	if (writtenlen) {
305		if (inode->i_size < pos + writtenlen) {
306			inode->i_size = pos + writtenlen;
307			inode->i_blocks = (inode->i_size + 511) >> 9;
308
309			inode_set_mtime_to_ts(inode,
310					      inode_set_ctime_to_ts(inode, ITIME(je32_to_cpu(ri->ctime))));
311		}
312	}
313
314	jffs2_free_raw_inode(ri);
315
316	if (start+writtenlen < end) {
317		/* generic_file_write has written more to the page cache than we've
318		   actually written to the medium. Mark the page !Uptodate so that
319		   it gets reread */
320		jffs2_dbg(1, "%s(): Not all bytes written. Marking page !uptodate\n",
321			__func__);
322		folio_clear_uptodate(folio);
323	}
324
325	jffs2_dbg(1, "%s() returning %d\n",
326		  __func__, writtenlen > 0 ? writtenlen : ret);
327	folio_unlock(folio);
328	folio_put(folio);
329	return writtenlen > 0 ? writtenlen : ret;
330}