2 * JFFS2 -- Journalling Flash File System, Version 2.
4 * Copyright (C) 2001-2003 Red Hat, Inc.
6 * Created by David Woodhouse <dwmw2@infradead.org>
8 * For licensing information, see the file 'LICENCE' in this directory.
10 * $Id: file.c,v 1.102 2005/07/06 12:13:09 dwmw2 Exp $
14 #include <linux/kernel.h>
15 #include <linux/slab.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>
24 extern int generic_file_open(struct inode *, struct file *) __attribute__((weak));
25 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) __attribute__((weak));
27 static int jffs2_commit_write (struct file *filp, struct page *pg,
28 unsigned start, unsigned end);
29 static int jffs2_prepare_write (struct file *filp, struct page *pg,
30 unsigned start, unsigned end);
31 static int jffs2_readpage (struct file *filp, struct page *pg);
33 int jffs2_fsync(struct file *filp, struct dentry *dentry, int datasync)
35 struct inode *inode = dentry->d_inode;
36 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
38 /* Trigger GC to flush any pending writes for this inode */
39 jffs2_flush_wbuf_gc(c, inode->i_ino);
44 struct file_operations jffs2_file_operations =
46 .llseek = generic_file_llseek,
47 .open = generic_file_open,
48 .read = generic_file_read,
49 .write = generic_file_write,
51 .mmap = generic_file_readonly_mmap,
53 .sendfile = generic_file_sendfile
56 /* jffs2_file_inode_operations */
58 struct inode_operations jffs2_file_inode_operations =
60 .setattr = jffs2_setattr
63 struct address_space_operations jffs2_file_address_operations =
65 .readpage = jffs2_readpage,
66 .prepare_write =jffs2_prepare_write,
67 .commit_write = jffs2_commit_write
70 static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg)
72 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
73 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
74 unsigned char *pg_buf;
77 D2(printk(KERN_DEBUG "jffs2_do_readpage_nolock(): ino #%lu, page at offset 0x%lx\n", inode->i_ino, pg->index << PAGE_CACHE_SHIFT));
79 BUG_ON(!PageLocked(pg));
82 /* FIXME: Can kmap fail? */
84 ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE);
87 ClearPageUptodate(pg);
94 flush_dcache_page(pg);
97 D2(printk(KERN_DEBUG "readpage finished\n"));
101 int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg)
103 int ret = jffs2_do_readpage_nolock(inode, pg);
109 static int jffs2_readpage (struct file *filp, struct page *pg)
111 struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host);
115 ret = jffs2_do_readpage_unlock(pg->mapping->host, pg);
120 static int jffs2_prepare_write (struct file *filp, struct page *pg,
121 unsigned start, unsigned end)
123 struct inode *inode = pg->mapping->host;
124 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
125 uint32_t pageofs = pg->index << PAGE_CACHE_SHIFT;
128 D1(printk(KERN_DEBUG "jffs2_prepare_write()\n"));
130 if (pageofs > inode->i_size) {
131 /* Make new hole frag from old EOF to new page */
132 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
133 struct jffs2_raw_inode ri;
134 struct jffs2_full_dnode *fn;
135 uint32_t phys_ofs, alloc_len;
137 D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
138 (unsigned int)inode->i_size, pageofs));
140 ret = jffs2_reserve_space(c, sizeof(ri), &phys_ofs, &alloc_len, ALLOC_NORMAL);
145 memset(&ri, 0, sizeof(ri));
147 ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
148 ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
149 ri.totlen = cpu_to_je32(sizeof(ri));
150 ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
152 ri.ino = cpu_to_je32(f->inocache->ino);
153 ri.version = cpu_to_je32(++f->highest_version);
154 ri.mode = cpu_to_jemode(inode->i_mode);
155 ri.uid = cpu_to_je16(inode->i_uid);
156 ri.gid = cpu_to_je16(inode->i_gid);
157 ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));
158 ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds());
159 ri.offset = cpu_to_je32(inode->i_size);
160 ri.dsize = cpu_to_je32(pageofs - inode->i_size);
161 ri.csize = cpu_to_je32(0);
162 ri.compr = JFFS2_COMPR_ZERO;
163 ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
164 ri.data_crc = cpu_to_je32(0);
166 fn = jffs2_write_dnode(c, f, &ri, NULL, 0, phys_ofs, ALLOC_NORMAL);
170 jffs2_complete_reservation(c);
174 ret = jffs2_add_full_dnode_to_inode(c, f, fn);
176 jffs2_mark_node_obsolete(c, f->metadata->raw);
177 jffs2_free_full_dnode(f->metadata);
181 D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in prepare_write, returned %d\n", ret));
182 jffs2_mark_node_obsolete(c, fn->raw);
183 jffs2_free_full_dnode(fn);
184 jffs2_complete_reservation(c);
188 jffs2_complete_reservation(c);
189 inode->i_size = pageofs;
193 /* Read in the page if it wasn't already present, unless it's a whole page */
194 if (!PageUptodate(pg) && (start || end < PAGE_CACHE_SIZE)) {
196 ret = jffs2_do_readpage_nolock(inode, pg);
199 D1(printk(KERN_DEBUG "end prepare_write(). pg->flags %lx\n", pg->flags));
203 static int jffs2_commit_write (struct file *filp, struct page *pg,
204 unsigned start, unsigned end)
206 /* Actually commit the write from the page cache page we're looking at.
207 * For now, we write the full page out each time. It sucks, but it's simple
209 struct inode *inode = pg->mapping->host;
210 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
211 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
212 struct jffs2_raw_inode *ri;
213 unsigned aligned_start = start & ~3;
215 uint32_t writtenlen = 0;
217 D1(printk(KERN_DEBUG "jffs2_commit_write(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n",
218 inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, pg->flags));
220 if (!start && end == PAGE_CACHE_SIZE) {
221 /* We need to avoid deadlock with page_cache_read() in
222 jffs2_garbage_collect_pass(). So we have to mark the
223 page up to date, to prevent page_cache_read() from
224 trying to re-lock it. */
228 ri = jffs2_alloc_raw_inode();
231 D1(printk(KERN_DEBUG "jffs2_commit_write(): Allocation of raw inode failed\n"));
235 /* Set the fields that the generic jffs2_write_inode_range() code can't find */
236 ri->ino = cpu_to_je32(inode->i_ino);
237 ri->mode = cpu_to_jemode(inode->i_mode);
238 ri->uid = cpu_to_je16(inode->i_uid);
239 ri->gid = cpu_to_je16(inode->i_gid);
240 ri->isize = cpu_to_je32((uint32_t)inode->i_size);
241 ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds());
243 /* In 2.4, it was already kmapped by generic_file_write(). Doesn't
244 hurt to do it again. The alternative is ifdefs, which are ugly. */
247 ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start,
248 (pg->index << PAGE_CACHE_SHIFT) + aligned_start,
249 end - aligned_start, &writtenlen);
254 /* There was an error writing. */
258 /* Adjust writtenlen for the padding we did, so we don't confuse our caller */
259 if (writtenlen < (start&3))
262 writtenlen -= (start&3);
265 if (inode->i_size < (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen) {
266 inode->i_size = (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen;
267 inode->i_blocks = (inode->i_size + 511) >> 9;
269 inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime));
273 jffs2_free_raw_inode(ri);
275 if (start+writtenlen < end) {
276 /* generic_file_write has written more to the page cache than we've
277 actually written to the medium. Mark the page !Uptodate so that
279 D1(printk(KERN_DEBUG "jffs2_commit_write(): Not all bytes written. Marking page !uptodate\n"));
281 ClearPageUptodate(pg);
284 D1(printk(KERN_DEBUG "jffs2_commit_write() returning %d\n",writtenlen?writtenlen:ret));
285 return writtenlen?writtenlen:ret;