2 * JFFS2 -- Journalling Flash File System, Version 2.
4 * Copyright (C) 2001, 2002 Red Hat, Inc.
6 * Created by David Woodhouse <dwmw2@cambridge.redhat.com>
8 * For licensing information, see the file 'LICENCE' in this directory.
14 #include <linux/kernel.h>
15 #include <linux/pagemap.h>
16 #include <linux/crc32.h>
19 int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg)
21 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
22 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
23 unsigned char *pg_buf;
26 D1(printk(KERN_DEBUG "jffs2_do_readpage_nolock(): ino #%lu, page at offset 0x%lx\n", inode->i_ino, pg->index << PAGE_CACHE_SHIFT));
31 pg_buf = (char *)kmap(pg);
32 /* FIXME: Can kmap fail? */
34 ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE);
37 ClearPageUptodate(pg);
44 flush_dcache_page(pg);
47 D1(printk(KERN_DEBUG "readpage finished\n"));
51 int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg)
53 int ret = jffs2_do_readpage_nolock(inode, pg);
59 //int jffs2_readpage (struct file *filp, struct page *pg)
60 int jffs2_readpage (struct inode *d_inode, struct page *pg)
62 // struct jffs2_inode_info *f = JFFS2_INODE_INFO(d_inode);
66 ret = jffs2_do_readpage_unlock(d_inode, pg);
71 //int jffs2_prepare_write (struct file *filp, struct page *pg, unsigned start, unsigned end)
72 int jffs2_prepare_write (struct inode *d_inode, struct page *pg, unsigned start, unsigned end)
74 struct inode *inode = d_inode;
75 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
76 uint32_t pageofs = pg->index << PAGE_CACHE_SHIFT;
79 D1(printk(KERN_DEBUG "jffs2_prepare_write()\n"));
81 if (pageofs > inode->i_size) {
82 /* Make new hole frag from old EOF to new page */
83 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
84 struct jffs2_raw_inode ri;
85 struct jffs2_full_dnode *fn;
86 uint32_t phys_ofs, alloc_len;
88 D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n",
89 (unsigned int)inode->i_size, pageofs));
91 ret = jffs2_reserve_space(c, sizeof(ri), &phys_ofs, &alloc_len, ALLOC_NORMAL);
96 memset(&ri, 0, sizeof(ri));
98 ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
99 ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
100 ri.totlen = cpu_to_je32(sizeof(ri));
101 ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4));
103 ri.ino = cpu_to_je32(f->inocache->ino);
104 ri.version = cpu_to_je32(++f->highest_version);
105 ri.mode = cpu_to_jemode(inode->i_mode);
106 ri.uid = cpu_to_je16(inode->i_uid);
107 ri.gid = cpu_to_je16(inode->i_gid);
109 ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs));
110 ri.atime = ri.ctime = ri.mtime = cpu_to_je32(cyg_timestamp());
111 ri.offset = cpu_to_je32(inode->i_size);
112 ri.dsize = cpu_to_je32(pageofs - inode->i_size);
113 ri.csize = cpu_to_je32(0);
114 ri.compr = JFFS2_COMPR_ZERO;
115 ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8));
116 ri.data_crc = cpu_to_je32(0);
118 fn = jffs2_write_dnode(c, f, &ri, NULL, 0, phys_ofs, NULL);
119 jffs2_complete_reservation(c);
125 ret = jffs2_add_full_dnode_to_inode(c, f, fn);
127 jffs2_mark_node_obsolete(c, f->metadata->raw);
128 jffs2_free_full_dnode(f->metadata);
132 D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in prepare_write, returned %d\n", ret));
133 jffs2_mark_node_obsolete(c, fn->raw);
134 jffs2_free_full_dnode(fn);
138 inode->i_size = pageofs;
143 /* Read in the page if it wasn't already present, unless it's a whole page */
144 // eCos has no concept of uptodate and by default always reads pages afresh
145 if (!Page_Uptodate(pg) && (start || end < PAGE_CACHE_SIZE)) {
147 ret = jffs2_do_readpage_nolock(inode, pg);
150 D1(printk(KERN_DEBUG "end prepare_write()\n"));
154 //int jffs2_commit_write (struct file *filp, struct page *pg, unsigned start, unsigned end)
155 int jffs2_commit_write (struct inode *d_inode, struct page *pg, unsigned start, unsigned end)
157 /* Actually commit the write from the page cache page we're looking at.
158 * For now, we write the full page out each time. It sucks, but it's simple
160 struct inode *inode = d_inode;
161 struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
162 struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
163 struct jffs2_raw_inode *ri;
165 uint32_t writtenlen = 0;
167 D1(printk(KERN_DEBUG "jffs2_commit_write(): ino #%lu, page at 0x%lx, range %d-%d\n",
168 inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end));
171 ri = jffs2_alloc_raw_inode();
173 D1(printk(KERN_DEBUG "jffs2_commit_write(): Allocation of raw inode failed\n"));
177 /* Set the fields that the generic jffs2_write_inode_range() code can't find */
178 ri->ino = cpu_to_je32(inode->i_ino);
179 ri->mode = cpu_to_jemode(inode->i_mode);
180 ri->uid = cpu_to_je16(inode->i_uid);
181 ri->gid = cpu_to_je16(inode->i_gid);
182 ri->isize = cpu_to_je32((uint32_t)inode->i_size);
183 ri->atime = ri->ctime = ri->mtime = cpu_to_je32(cyg_timestamp());
185 ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + start,
186 (pg->index << PAGE_CACHE_SHIFT) + start,
187 end - start, &writtenlen);
190 /* There was an error writing. */
195 if (inode->i_size < (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen) {
196 inode->i_size = (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen;
197 inode->i_ctime = inode->i_mtime = je32_to_cpu(ri->ctime);
201 jffs2_free_raw_inode(ri);
203 if (start+writtenlen < end) {
204 /* generic_file_write has written more to the page cache than we've
205 actually written to the medium. Mark the page !Uptodate so that
207 D1(printk(KERN_DEBUG "jffs2_commit_write(): Not all bytes written. Marking page !uptodate\n"));
209 ClearPageUptodate(pg);
212 D1(printk(KERN_DEBUG "jffs2_commit_write() returning %d\n",writtenlen?writtenlen:ret));
213 return writtenlen?writtenlen:ret;