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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright (C) 2001-2003 Red Hat, Inc.
5 *
6 * Created by David Woodhouse <dwmw2@infradead.org>
7 *
8 * For licensing information, see the file 'LICENCE' in this directory.
9 *
Todd Poynor4fc67fb2005-10-19 00:29:38 +010010 * $Id: file.c,v 1.104 2005/10/18 23:29:35 tpoynor Exp $
Linus Torvalds1da177e2005-04-16 15:20:36 -070011 *
12 */
13
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/kernel.h>
15#include <linux/slab.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
Linus Torvalds1da177e2005-04-16 15:20:36 -070024static int jffs2_commit_write (struct file *filp, struct page *pg,
25 unsigned start, unsigned end);
26static int jffs2_prepare_write (struct file *filp, struct page *pg,
27 unsigned start, unsigned end);
28static int jffs2_readpage (struct file *filp, struct page *pg);
29
30int jffs2_fsync(struct file *filp, struct dentry *dentry, int datasync)
31{
32 struct inode *inode = dentry->d_inode;
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);
Thomas Gleixner182ec4e2005-11-07 11:16:07 +000037
38 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -070039}
40
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -080041const struct file_operations jffs2_file_operations =
Linus Torvalds1da177e2005-04-16 15:20:36 -070042{
43 .llseek = generic_file_llseek,
44 .open = generic_file_open,
Badari Pulavarty543ade12006-09-30 23:28:48 -070045 .read = do_sync_read,
46 .aio_read = generic_file_aio_read,
47 .write = do_sync_write,
48 .aio_write = generic_file_aio_write,
Linus Torvalds1da177e2005-04-16 15:20:36 -070049 .ioctl = jffs2_ioctl,
50 .mmap = generic_file_readonly_mmap,
51 .fsync = jffs2_fsync,
Linus Torvalds1da177e2005-04-16 15:20:36 -070052 .sendfile = generic_file_sendfile
Linus Torvalds1da177e2005-04-16 15:20:36 -070053};
54
55/* jffs2_file_inode_operations */
56
57struct inode_operations jffs2_file_inode_operations =
58{
KaiGai Koheiaa98d7c2006-05-13 15:09:47 +090059 .permission = jffs2_permission,
60 .setattr = jffs2_setattr,
61 .setxattr = jffs2_setxattr,
62 .getxattr = jffs2_getxattr,
63 .listxattr = jffs2_listxattr,
64 .removexattr = jffs2_removexattr
Linus Torvalds1da177e2005-04-16 15:20:36 -070065};
66
Christoph Hellwigf5e54d62006-06-28 04:26:44 -070067const struct address_space_operations jffs2_file_address_operations =
Linus Torvalds1da177e2005-04-16 15:20:36 -070068{
69 .readpage = jffs2_readpage,
70 .prepare_write =jffs2_prepare_write,
71 .commit_write = jffs2_commit_write
72};
73
74static 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
Matt Mackallcd7619d2005-05-01 08:59:01 -070083 BUG_ON(!PageLocked(pg));
Linus Torvalds1da177e2005-04-16 15:20:36 -070084
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"));
102 return 0;
103}
104
105int 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
113static 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;
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000117
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 down(&f->sem);
119 ret = jffs2_do_readpage_unlock(pg->mapping->host, pg);
120 up(&f->sem);
121 return ret;
122}
123
124static int jffs2_prepare_write (struct file *filp, struct page *pg,
125 unsigned start, unsigned end)
126{
127 struct inode *inode = pg->mapping->host;
128 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
129 uint32_t pageofs = pg->index << PAGE_CACHE_SHIFT;
130 int ret = 0;
131
132 D1(printk(KERN_DEBUG "jffs2_prepare_write()\n"));
133
134 if (pageofs > inode->i_size) {
135 /* Make new hole frag from old EOF to new page */
136 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
137 struct jffs2_raw_inode ri;
138 struct jffs2_full_dnode *fn;
David Woodhouse9fe48542006-05-23 00:38:06 +0100139 uint32_t alloc_len;
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000140
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141 D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
142 (unsigned int)inode->i_size, pageofs));
143
David Woodhouse9fe48542006-05-23 00:38:06 +0100144 ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len,
145 ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146 if (ret)
147 return ret;
148
149 down(&f->sem);
150 memset(&ri, 0, sizeof(ri));
151
152 ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
153 ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
154 ri.totlen = cpu_to_je32(sizeof(ri));
155 ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
156
157 ri.ino = cpu_to_je32(f->inocache->ino);
158 ri.version = cpu_to_je32(++f->highest_version);
159 ri.mode = cpu_to_jemode(inode->i_mode);
160 ri.uid = cpu_to_je16(inode->i_uid);
161 ri.gid = cpu_to_je16(inode->i_gid);
162 ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));
163 ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds());
164 ri.offset = cpu_to_je32(inode->i_size);
165 ri.dsize = cpu_to_je32(pageofs - inode->i_size);
166 ri.csize = cpu_to_je32(0);
167 ri.compr = JFFS2_COMPR_ZERO;
168 ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
169 ri.data_crc = cpu_to_je32(0);
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000170
David Woodhouse9fe48542006-05-23 00:38:06 +0100171 fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172
173 if (IS_ERR(fn)) {
174 ret = PTR_ERR(fn);
175 jffs2_complete_reservation(c);
176 up(&f->sem);
177 return ret;
178 }
179 ret = jffs2_add_full_dnode_to_inode(c, f, fn);
180 if (f->metadata) {
181 jffs2_mark_node_obsolete(c, f->metadata->raw);
182 jffs2_free_full_dnode(f->metadata);
183 f->metadata = NULL;
184 }
185 if (ret) {
186 D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in prepare_write, returned %d\n", ret));
187 jffs2_mark_node_obsolete(c, fn->raw);
188 jffs2_free_full_dnode(fn);
189 jffs2_complete_reservation(c);
190 up(&f->sem);
191 return ret;
192 }
193 jffs2_complete_reservation(c);
194 inode->i_size = pageofs;
195 up(&f->sem);
196 }
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000197
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 /* Read in the page if it wasn't already present, unless it's a whole page */
199 if (!PageUptodate(pg) && (start || end < PAGE_CACHE_SIZE)) {
200 down(&f->sem);
201 ret = jffs2_do_readpage_nolock(inode, pg);
202 up(&f->sem);
203 }
204 D1(printk(KERN_DEBUG "end prepare_write(). pg->flags %lx\n", pg->flags));
205 return ret;
206}
207
208static int jffs2_commit_write (struct file *filp, struct page *pg,
209 unsigned start, unsigned end)
210{
211 /* Actually commit the write from the page cache page we're looking at.
212 * For now, we write the full page out each time. It sucks, but it's simple
213 */
214 struct inode *inode = pg->mapping->host;
215 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
216 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
217 struct jffs2_raw_inode *ri;
218 unsigned aligned_start = start & ~3;
219 int ret = 0;
220 uint32_t writtenlen = 0;
221
222 D1(printk(KERN_DEBUG "jffs2_commit_write(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n",
223 inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, pg->flags));
224
David Woodhousecf5eba52006-05-14 04:06:24 +0100225 if (end == PAGE_CACHE_SIZE) {
226 if (!start) {
227 /* We need to avoid deadlock with page_cache_read() in
228 jffs2_garbage_collect_pass(). So we have to mark the
229 page up to date, to prevent page_cache_read() from
230 trying to re-lock it. */
231 SetPageUptodate(pg);
232 } else {
233 /* When writing out the end of a page, write out the
234 _whole_ page. This helps to reduce the number of
235 nodes in files which have many short writes, like
236 syslog files. */
237 start = aligned_start = 0;
238 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239 }
240
241 ri = jffs2_alloc_raw_inode();
242
243 if (!ri) {
244 D1(printk(KERN_DEBUG "jffs2_commit_write(): Allocation of raw inode failed\n"));
245 return -ENOMEM;
246 }
247
248 /* Set the fields that the generic jffs2_write_inode_range() code can't find */
249 ri->ino = cpu_to_je32(inode->i_ino);
250 ri->mode = cpu_to_jemode(inode->i_mode);
251 ri->uid = cpu_to_je16(inode->i_uid);
252 ri->gid = cpu_to_je16(inode->i_gid);
253 ri->isize = cpu_to_je32((uint32_t)inode->i_size);
254 ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds());
255
256 /* In 2.4, it was already kmapped by generic_file_write(). Doesn't
257 hurt to do it again. The alternative is ifdefs, which are ugly. */
258 kmap(pg);
259
260 ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start,
261 (pg->index << PAGE_CACHE_SHIFT) + aligned_start,
262 end - aligned_start, &writtenlen);
263
264 kunmap(pg);
265
266 if (ret) {
267 /* There was an error writing. */
268 SetPageError(pg);
269 }
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000270
Linus Torvalds1da177e2005-04-16 15:20:36 -0700271 /* Adjust writtenlen for the padding we did, so we don't confuse our caller */
272 if (writtenlen < (start&3))
273 writtenlen = 0;
274 else
275 writtenlen -= (start&3);
276
277 if (writtenlen) {
278 if (inode->i_size < (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen) {
279 inode->i_size = (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen;
280 inode->i_blocks = (inode->i_size + 511) >> 9;
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000281
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282 inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime));
283 }
284 }
285
286 jffs2_free_raw_inode(ri);
287
288 if (start+writtenlen < end) {
289 /* generic_file_write has written more to the page cache than we've
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000290 actually written to the medium. Mark the page !Uptodate so that
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 it gets reread */
292 D1(printk(KERN_DEBUG "jffs2_commit_write(): Not all bytes written. Marking page !uptodate\n"));
293 SetPageError(pg);
294 ClearPageUptodate(pg);
295 }
296
Todd Poynor4fc67fb2005-10-19 00:29:38 +0100297 D1(printk(KERN_DEBUG "jffs2_commit_write() returning %d\n",start+writtenlen==end?0:ret));
298 return start+writtenlen==end?0:ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299}