Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 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 Poynor | 4fc67fb | 2005-10-19 00:29:38 +0100 | [diff] [blame] | 10 | * $Id: file.c,v 1.104 2005/10/18 23:29:35 tpoynor Exp $ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | * |
| 12 | */ |
| 13 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 14 | #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 Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | static int jffs2_commit_write (struct file *filp, struct page *pg, |
| 25 | unsigned start, unsigned end); |
| 26 | static int jffs2_prepare_write (struct file *filp, struct page *pg, |
| 27 | unsigned start, unsigned end); |
| 28 | static int jffs2_readpage (struct file *filp, struct page *pg); |
| 29 | |
| 30 | int 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 Gleixner | 182ec4e | 2005-11-07 11:16:07 +0000 | [diff] [blame] | 37 | |
| 38 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | } |
| 40 | |
| 41 | struct file_operations jffs2_file_operations = |
| 42 | { |
| 43 | .llseek = generic_file_llseek, |
| 44 | .open = generic_file_open, |
| 45 | .read = generic_file_read, |
| 46 | .write = generic_file_write, |
| 47 | .ioctl = jffs2_ioctl, |
| 48 | .mmap = generic_file_readonly_mmap, |
| 49 | .fsync = jffs2_fsync, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | .sendfile = generic_file_sendfile |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | }; |
| 52 | |
| 53 | /* jffs2_file_inode_operations */ |
| 54 | |
| 55 | struct inode_operations jffs2_file_inode_operations = |
| 56 | { |
| 57 | .setattr = jffs2_setattr |
| 58 | }; |
| 59 | |
| 60 | struct address_space_operations jffs2_file_address_operations = |
| 61 | { |
| 62 | .readpage = jffs2_readpage, |
| 63 | .prepare_write =jffs2_prepare_write, |
| 64 | .commit_write = jffs2_commit_write |
| 65 | }; |
| 66 | |
| 67 | static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg) |
| 68 | { |
| 69 | struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); |
| 70 | struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); |
| 71 | unsigned char *pg_buf; |
| 72 | int ret; |
| 73 | |
| 74 | D2(printk(KERN_DEBUG "jffs2_do_readpage_nolock(): ino #%lu, page at offset 0x%lx\n", inode->i_ino, pg->index << PAGE_CACHE_SHIFT)); |
| 75 | |
Matt Mackall | cd7619d | 2005-05-01 08:59:01 -0700 | [diff] [blame] | 76 | BUG_ON(!PageLocked(pg)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | |
| 78 | pg_buf = kmap(pg); |
| 79 | /* FIXME: Can kmap fail? */ |
| 80 | |
| 81 | ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE); |
| 82 | |
| 83 | if (ret) { |
| 84 | ClearPageUptodate(pg); |
| 85 | SetPageError(pg); |
| 86 | } else { |
| 87 | SetPageUptodate(pg); |
| 88 | ClearPageError(pg); |
| 89 | } |
| 90 | |
| 91 | flush_dcache_page(pg); |
| 92 | kunmap(pg); |
| 93 | |
| 94 | D2(printk(KERN_DEBUG "readpage finished\n")); |
| 95 | return 0; |
| 96 | } |
| 97 | |
| 98 | int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg) |
| 99 | { |
| 100 | int ret = jffs2_do_readpage_nolock(inode, pg); |
| 101 | unlock_page(pg); |
| 102 | return ret; |
| 103 | } |
| 104 | |
| 105 | |
| 106 | static int jffs2_readpage (struct file *filp, struct page *pg) |
| 107 | { |
| 108 | struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host); |
| 109 | int ret; |
Thomas Gleixner | 182ec4e | 2005-11-07 11:16:07 +0000 | [diff] [blame] | 110 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 111 | down(&f->sem); |
| 112 | ret = jffs2_do_readpage_unlock(pg->mapping->host, pg); |
| 113 | up(&f->sem); |
| 114 | return ret; |
| 115 | } |
| 116 | |
| 117 | static int jffs2_prepare_write (struct file *filp, struct page *pg, |
| 118 | unsigned start, unsigned end) |
| 119 | { |
| 120 | struct inode *inode = pg->mapping->host; |
| 121 | struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); |
| 122 | uint32_t pageofs = pg->index << PAGE_CACHE_SHIFT; |
| 123 | int ret = 0; |
| 124 | |
| 125 | D1(printk(KERN_DEBUG "jffs2_prepare_write()\n")); |
| 126 | |
| 127 | if (pageofs > inode->i_size) { |
| 128 | /* Make new hole frag from old EOF to new page */ |
| 129 | struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); |
| 130 | struct jffs2_raw_inode ri; |
| 131 | struct jffs2_full_dnode *fn; |
| 132 | uint32_t phys_ofs, alloc_len; |
Thomas Gleixner | 182ec4e | 2005-11-07 11:16:07 +0000 | [diff] [blame] | 133 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n", |
| 135 | (unsigned int)inode->i_size, pageofs)); |
| 136 | |
Ferenc Havasi | e631ddb | 2005-09-07 09:35:26 +0100 | [diff] [blame] | 137 | ret = jffs2_reserve_space(c, sizeof(ri), &phys_ofs, &alloc_len, |
| 138 | ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | if (ret) |
| 140 | return ret; |
| 141 | |
| 142 | down(&f->sem); |
| 143 | memset(&ri, 0, sizeof(ri)); |
| 144 | |
| 145 | ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); |
| 146 | ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); |
| 147 | ri.totlen = cpu_to_je32(sizeof(ri)); |
| 148 | ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); |
| 149 | |
| 150 | ri.ino = cpu_to_je32(f->inocache->ino); |
| 151 | ri.version = cpu_to_je32(++f->highest_version); |
| 152 | ri.mode = cpu_to_jemode(inode->i_mode); |
| 153 | ri.uid = cpu_to_je16(inode->i_uid); |
| 154 | ri.gid = cpu_to_je16(inode->i_gid); |
| 155 | ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs)); |
| 156 | ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds()); |
| 157 | ri.offset = cpu_to_je32(inode->i_size); |
| 158 | ri.dsize = cpu_to_je32(pageofs - inode->i_size); |
| 159 | ri.csize = cpu_to_je32(0); |
| 160 | ri.compr = JFFS2_COMPR_ZERO; |
| 161 | ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); |
| 162 | ri.data_crc = cpu_to_je32(0); |
Thomas Gleixner | 182ec4e | 2005-11-07 11:16:07 +0000 | [diff] [blame] | 163 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 164 | fn = jffs2_write_dnode(c, f, &ri, NULL, 0, phys_ofs, ALLOC_NORMAL); |
| 165 | |
| 166 | if (IS_ERR(fn)) { |
| 167 | ret = PTR_ERR(fn); |
| 168 | jffs2_complete_reservation(c); |
| 169 | up(&f->sem); |
| 170 | return ret; |
| 171 | } |
| 172 | ret = jffs2_add_full_dnode_to_inode(c, f, fn); |
| 173 | if (f->metadata) { |
| 174 | jffs2_mark_node_obsolete(c, f->metadata->raw); |
| 175 | jffs2_free_full_dnode(f->metadata); |
| 176 | f->metadata = NULL; |
| 177 | } |
| 178 | if (ret) { |
| 179 | D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in prepare_write, returned %d\n", ret)); |
| 180 | jffs2_mark_node_obsolete(c, fn->raw); |
| 181 | jffs2_free_full_dnode(fn); |
| 182 | jffs2_complete_reservation(c); |
| 183 | up(&f->sem); |
| 184 | return ret; |
| 185 | } |
| 186 | jffs2_complete_reservation(c); |
| 187 | inode->i_size = pageofs; |
| 188 | up(&f->sem); |
| 189 | } |
Thomas Gleixner | 182ec4e | 2005-11-07 11:16:07 +0000 | [diff] [blame] | 190 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | /* Read in the page if it wasn't already present, unless it's a whole page */ |
| 192 | if (!PageUptodate(pg) && (start || end < PAGE_CACHE_SIZE)) { |
| 193 | down(&f->sem); |
| 194 | ret = jffs2_do_readpage_nolock(inode, pg); |
| 195 | up(&f->sem); |
| 196 | } |
| 197 | D1(printk(KERN_DEBUG "end prepare_write(). pg->flags %lx\n", pg->flags)); |
| 198 | return ret; |
| 199 | } |
| 200 | |
| 201 | static int jffs2_commit_write (struct file *filp, struct page *pg, |
| 202 | unsigned start, unsigned end) |
| 203 | { |
| 204 | /* Actually commit the write from the page cache page we're looking at. |
| 205 | * For now, we write the full page out each time. It sucks, but it's simple |
| 206 | */ |
| 207 | struct inode *inode = pg->mapping->host; |
| 208 | struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); |
| 209 | struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); |
| 210 | struct jffs2_raw_inode *ri; |
| 211 | unsigned aligned_start = start & ~3; |
| 212 | int ret = 0; |
| 213 | uint32_t writtenlen = 0; |
| 214 | |
| 215 | D1(printk(KERN_DEBUG "jffs2_commit_write(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n", |
| 216 | inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, pg->flags)); |
| 217 | |
| 218 | if (!start && end == PAGE_CACHE_SIZE) { |
| 219 | /* We need to avoid deadlock with page_cache_read() in |
| 220 | jffs2_garbage_collect_pass(). So we have to mark the |
Thomas Gleixner | 182ec4e | 2005-11-07 11:16:07 +0000 | [diff] [blame] | 221 | page up to date, to prevent page_cache_read() from |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 222 | trying to re-lock it. */ |
| 223 | SetPageUptodate(pg); |
| 224 | } |
| 225 | |
| 226 | ri = jffs2_alloc_raw_inode(); |
| 227 | |
| 228 | if (!ri) { |
| 229 | D1(printk(KERN_DEBUG "jffs2_commit_write(): Allocation of raw inode failed\n")); |
| 230 | return -ENOMEM; |
| 231 | } |
| 232 | |
| 233 | /* Set the fields that the generic jffs2_write_inode_range() code can't find */ |
| 234 | ri->ino = cpu_to_je32(inode->i_ino); |
| 235 | ri->mode = cpu_to_jemode(inode->i_mode); |
| 236 | ri->uid = cpu_to_je16(inode->i_uid); |
| 237 | ri->gid = cpu_to_je16(inode->i_gid); |
| 238 | ri->isize = cpu_to_je32((uint32_t)inode->i_size); |
| 239 | ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds()); |
| 240 | |
| 241 | /* In 2.4, it was already kmapped by generic_file_write(). Doesn't |
| 242 | hurt to do it again. The alternative is ifdefs, which are ugly. */ |
| 243 | kmap(pg); |
| 244 | |
| 245 | ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start, |
| 246 | (pg->index << PAGE_CACHE_SHIFT) + aligned_start, |
| 247 | end - aligned_start, &writtenlen); |
| 248 | |
| 249 | kunmap(pg); |
| 250 | |
| 251 | if (ret) { |
| 252 | /* There was an error writing. */ |
| 253 | SetPageError(pg); |
| 254 | } |
Thomas Gleixner | 182ec4e | 2005-11-07 11:16:07 +0000 | [diff] [blame] | 255 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 256 | /* Adjust writtenlen for the padding we did, so we don't confuse our caller */ |
| 257 | if (writtenlen < (start&3)) |
| 258 | writtenlen = 0; |
| 259 | else |
| 260 | writtenlen -= (start&3); |
| 261 | |
| 262 | if (writtenlen) { |
| 263 | if (inode->i_size < (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen) { |
| 264 | inode->i_size = (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen; |
| 265 | inode->i_blocks = (inode->i_size + 511) >> 9; |
Thomas Gleixner | 182ec4e | 2005-11-07 11:16:07 +0000 | [diff] [blame] | 266 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 267 | inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime)); |
| 268 | } |
| 269 | } |
| 270 | |
| 271 | jffs2_free_raw_inode(ri); |
| 272 | |
| 273 | if (start+writtenlen < end) { |
| 274 | /* generic_file_write has written more to the page cache than we've |
Thomas Gleixner | 182ec4e | 2005-11-07 11:16:07 +0000 | [diff] [blame] | 275 | actually written to the medium. Mark the page !Uptodate so that |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 276 | it gets reread */ |
| 277 | D1(printk(KERN_DEBUG "jffs2_commit_write(): Not all bytes written. Marking page !uptodate\n")); |
| 278 | SetPageError(pg); |
| 279 | ClearPageUptodate(pg); |
| 280 | } |
| 281 | |
Todd Poynor | 4fc67fb | 2005-10-19 00:29:38 +0100 | [diff] [blame] | 282 | D1(printk(KERN_DEBUG "jffs2_commit_write() returning %d\n",start+writtenlen==end?0:ret)); |
| 283 | return start+writtenlen==end?0:ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 284 | } |