11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * JFFS2 -- Journalling Flash File System, Version 2. 31da177e4SLinus Torvalds * 4c00c310eSDavid Woodhouse * Copyright © 2001-2007 Red Hat, Inc. 51da177e4SLinus Torvalds * 61da177e4SLinus Torvalds * Created by David Woodhouse <dwmw2@infradead.org> 71da177e4SLinus Torvalds * 81da177e4SLinus Torvalds * For licensing information, see the file 'LICENCE' in this directory. 91da177e4SLinus Torvalds * 101da177e4SLinus Torvalds */ 111da177e4SLinus Torvalds 121da177e4SLinus Torvalds #include <linux/kernel.h> 131da177e4SLinus Torvalds #include <linux/slab.h> 141da177e4SLinus Torvalds #include <linux/fs.h> 151da177e4SLinus Torvalds #include <linux/time.h> 161da177e4SLinus Torvalds #include <linux/pagemap.h> 171da177e4SLinus Torvalds #include <linux/highmem.h> 181da177e4SLinus Torvalds #include <linux/crc32.h> 191da177e4SLinus Torvalds #include <linux/jffs2.h> 201da177e4SLinus Torvalds #include "nodelist.h" 211da177e4SLinus Torvalds 22205c109aSNick Piggin static int jffs2_write_end(struct file *filp, struct address_space *mapping, 23205c109aSNick Piggin loff_t pos, unsigned len, unsigned copied, 24205c109aSNick Piggin struct page *pg, void *fsdata); 25205c109aSNick Piggin static int jffs2_write_begin(struct file *filp, struct address_space *mapping, 26205c109aSNick Piggin loff_t pos, unsigned len, unsigned flags, 27205c109aSNick Piggin struct page **pagep, void **fsdata); 281da177e4SLinus Torvalds static int jffs2_readpage (struct file *filp, struct page *pg); 291da177e4SLinus Torvalds 301da177e4SLinus Torvalds int jffs2_fsync(struct file *filp, struct dentry *dentry, int datasync) 311da177e4SLinus Torvalds { 321da177e4SLinus Torvalds struct inode *inode = dentry->d_inode; 331da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 341da177e4SLinus Torvalds 351da177e4SLinus Torvalds /* Trigger GC to flush any pending writes for this inode */ 361da177e4SLinus Torvalds jffs2_flush_wbuf_gc(c, inode->i_ino); 371da177e4SLinus Torvalds 381da177e4SLinus Torvalds return 0; 391da177e4SLinus Torvalds } 401da177e4SLinus Torvalds 414b6f5d20SArjan van de Ven const struct file_operations jffs2_file_operations = 421da177e4SLinus Torvalds { 431da177e4SLinus Torvalds .llseek = generic_file_llseek, 441da177e4SLinus Torvalds .open = generic_file_open, 45543ade1fSBadari Pulavarty .read = do_sync_read, 46543ade1fSBadari Pulavarty .aio_read = generic_file_aio_read, 47543ade1fSBadari Pulavarty .write = do_sync_write, 48543ade1fSBadari Pulavarty .aio_write = generic_file_aio_write, 490533400bSStoyan Gaydarov .unlocked_ioctl=jffs2_ioctl, 501da177e4SLinus Torvalds .mmap = generic_file_readonly_mmap, 511da177e4SLinus Torvalds .fsync = jffs2_fsync, 525ffc4ef4SJens Axboe .splice_read = generic_file_splice_read, 531da177e4SLinus Torvalds }; 541da177e4SLinus Torvalds 551da177e4SLinus Torvalds /* jffs2_file_inode_operations */ 561da177e4SLinus Torvalds 5792e1d5beSArjan van de Ven const struct inode_operations jffs2_file_inode_operations = 581da177e4SLinus Torvalds { 59aa98d7cfSKaiGai Kohei .permission = jffs2_permission, 60aa98d7cfSKaiGai Kohei .setattr = jffs2_setattr, 61aa98d7cfSKaiGai Kohei .setxattr = jffs2_setxattr, 62aa98d7cfSKaiGai Kohei .getxattr = jffs2_getxattr, 63aa98d7cfSKaiGai Kohei .listxattr = jffs2_listxattr, 64aa98d7cfSKaiGai Kohei .removexattr = jffs2_removexattr 651da177e4SLinus Torvalds }; 661da177e4SLinus Torvalds 67f5e54d6eSChristoph Hellwig const struct address_space_operations jffs2_file_address_operations = 681da177e4SLinus Torvalds { 691da177e4SLinus Torvalds .readpage = jffs2_readpage, 70205c109aSNick Piggin .write_begin = jffs2_write_begin, 71205c109aSNick Piggin .write_end = jffs2_write_end, 721da177e4SLinus Torvalds }; 731da177e4SLinus Torvalds 741da177e4SLinus Torvalds static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg) 751da177e4SLinus Torvalds { 761da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 771da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 781da177e4SLinus Torvalds unsigned char *pg_buf; 791da177e4SLinus Torvalds int ret; 801da177e4SLinus Torvalds 811da177e4SLinus Torvalds D2(printk(KERN_DEBUG "jffs2_do_readpage_nolock(): ino #%lu, page at offset 0x%lx\n", inode->i_ino, pg->index << PAGE_CACHE_SHIFT)); 821da177e4SLinus Torvalds 83cd7619d6SMatt Mackall BUG_ON(!PageLocked(pg)); 841da177e4SLinus Torvalds 851da177e4SLinus Torvalds pg_buf = kmap(pg); 861da177e4SLinus Torvalds /* FIXME: Can kmap fail? */ 871da177e4SLinus Torvalds 881da177e4SLinus Torvalds ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE); 891da177e4SLinus Torvalds 901da177e4SLinus Torvalds if (ret) { 911da177e4SLinus Torvalds ClearPageUptodate(pg); 921da177e4SLinus Torvalds SetPageError(pg); 931da177e4SLinus Torvalds } else { 941da177e4SLinus Torvalds SetPageUptodate(pg); 951da177e4SLinus Torvalds ClearPageError(pg); 961da177e4SLinus Torvalds } 971da177e4SLinus Torvalds 981da177e4SLinus Torvalds flush_dcache_page(pg); 991da177e4SLinus Torvalds kunmap(pg); 1001da177e4SLinus Torvalds 1011da177e4SLinus Torvalds D2(printk(KERN_DEBUG "readpage finished\n")); 10257ca7debSAnders Grafström return ret; 1031da177e4SLinus Torvalds } 1041da177e4SLinus Torvalds 1051da177e4SLinus Torvalds int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg) 1061da177e4SLinus Torvalds { 1071da177e4SLinus Torvalds int ret = jffs2_do_readpage_nolock(inode, pg); 1081da177e4SLinus Torvalds unlock_page(pg); 1091da177e4SLinus Torvalds return ret; 1101da177e4SLinus Torvalds } 1111da177e4SLinus Torvalds 1121da177e4SLinus Torvalds 1131da177e4SLinus Torvalds static int jffs2_readpage (struct file *filp, struct page *pg) 1141da177e4SLinus Torvalds { 1151da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host); 1161da177e4SLinus Torvalds int ret; 1171da177e4SLinus Torvalds 118ced22070SDavid Woodhouse mutex_lock(&f->sem); 1191da177e4SLinus Torvalds ret = jffs2_do_readpage_unlock(pg->mapping->host, pg); 120ced22070SDavid Woodhouse mutex_unlock(&f->sem); 1211da177e4SLinus Torvalds return ret; 1221da177e4SLinus Torvalds } 1231da177e4SLinus Torvalds 124205c109aSNick Piggin static int jffs2_write_begin(struct file *filp, struct address_space *mapping, 125205c109aSNick Piggin loff_t pos, unsigned len, unsigned flags, 126205c109aSNick Piggin struct page **pagep, void **fsdata) 1271da177e4SLinus Torvalds { 128205c109aSNick Piggin struct page *pg; 129205c109aSNick Piggin struct inode *inode = mapping->host; 1301da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 131205c109aSNick Piggin pgoff_t index = pos >> PAGE_CACHE_SHIFT; 132abe2f414SAlexey Korolev uint32_t pageofs = index << PAGE_CACHE_SHIFT; 1331da177e4SLinus Torvalds int ret = 0; 1341da177e4SLinus Torvalds 13554566b2cSNick Piggin pg = grab_cache_page_write_begin(mapping, index, flags); 136205c109aSNick Piggin if (!pg) 137205c109aSNick Piggin return -ENOMEM; 138205c109aSNick Piggin *pagep = pg; 139205c109aSNick Piggin 140205c109aSNick Piggin D1(printk(KERN_DEBUG "jffs2_write_begin()\n")); 1411da177e4SLinus Torvalds 1421da177e4SLinus Torvalds if (pageofs > inode->i_size) { 1431da177e4SLinus Torvalds /* Make new hole frag from old EOF to new page */ 1441da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 1451da177e4SLinus Torvalds struct jffs2_raw_inode ri; 1461da177e4SLinus Torvalds struct jffs2_full_dnode *fn; 1479fe4854cSDavid Woodhouse uint32_t alloc_len; 1481da177e4SLinus Torvalds 1491da177e4SLinus Torvalds D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n", 1501da177e4SLinus Torvalds (unsigned int)inode->i_size, pageofs)); 1511da177e4SLinus Torvalds 1529fe4854cSDavid Woodhouse ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len, 153e631ddbaSFerenc Havasi ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE); 1541da177e4SLinus Torvalds if (ret) 155205c109aSNick Piggin goto out_page; 1561da177e4SLinus Torvalds 157ced22070SDavid Woodhouse mutex_lock(&f->sem); 1581da177e4SLinus Torvalds memset(&ri, 0, sizeof(ri)); 1591da177e4SLinus Torvalds 1601da177e4SLinus Torvalds ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 1611da177e4SLinus Torvalds ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 1621da177e4SLinus Torvalds ri.totlen = cpu_to_je32(sizeof(ri)); 1631da177e4SLinus Torvalds ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 1641da177e4SLinus Torvalds 1651da177e4SLinus Torvalds ri.ino = cpu_to_je32(f->inocache->ino); 1661da177e4SLinus Torvalds ri.version = cpu_to_je32(++f->highest_version); 1671da177e4SLinus Torvalds ri.mode = cpu_to_jemode(inode->i_mode); 1681da177e4SLinus Torvalds ri.uid = cpu_to_je16(inode->i_uid); 1691da177e4SLinus Torvalds ri.gid = cpu_to_je16(inode->i_gid); 1701da177e4SLinus Torvalds ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs)); 1711da177e4SLinus Torvalds ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds()); 1721da177e4SLinus Torvalds ri.offset = cpu_to_je32(inode->i_size); 1731da177e4SLinus Torvalds ri.dsize = cpu_to_je32(pageofs - inode->i_size); 1741da177e4SLinus Torvalds ri.csize = cpu_to_je32(0); 1751da177e4SLinus Torvalds ri.compr = JFFS2_COMPR_ZERO; 1761da177e4SLinus Torvalds ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 1771da177e4SLinus Torvalds ri.data_crc = cpu_to_je32(0); 1781da177e4SLinus Torvalds 1799fe4854cSDavid Woodhouse fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL); 1801da177e4SLinus Torvalds 1811da177e4SLinus Torvalds if (IS_ERR(fn)) { 1821da177e4SLinus Torvalds ret = PTR_ERR(fn); 1831da177e4SLinus Torvalds jffs2_complete_reservation(c); 184ced22070SDavid Woodhouse mutex_unlock(&f->sem); 185205c109aSNick Piggin goto out_page; 1861da177e4SLinus Torvalds } 1871da177e4SLinus Torvalds ret = jffs2_add_full_dnode_to_inode(c, f, fn); 1881da177e4SLinus Torvalds if (f->metadata) { 1891da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, f->metadata->raw); 1901da177e4SLinus Torvalds jffs2_free_full_dnode(f->metadata); 1911da177e4SLinus Torvalds f->metadata = NULL; 1921da177e4SLinus Torvalds } 1931da177e4SLinus Torvalds if (ret) { 194205c109aSNick Piggin D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n", ret)); 1951da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, fn->raw); 1961da177e4SLinus Torvalds jffs2_free_full_dnode(fn); 1971da177e4SLinus Torvalds jffs2_complete_reservation(c); 198ced22070SDavid Woodhouse mutex_unlock(&f->sem); 199205c109aSNick Piggin goto out_page; 2001da177e4SLinus Torvalds } 2011da177e4SLinus Torvalds jffs2_complete_reservation(c); 2021da177e4SLinus Torvalds inode->i_size = pageofs; 203ced22070SDavid Woodhouse mutex_unlock(&f->sem); 2041da177e4SLinus Torvalds } 2051da177e4SLinus Torvalds 206205c109aSNick Piggin /* 207205c109aSNick Piggin * Read in the page if it wasn't already present. Cannot optimize away 208205c109aSNick Piggin * the whole page write case until jffs2_write_end can handle the 209205c109aSNick Piggin * case of a short-copy. 210205c109aSNick Piggin */ 211205c109aSNick Piggin if (!PageUptodate(pg)) { 212ced22070SDavid Woodhouse mutex_lock(&f->sem); 2131da177e4SLinus Torvalds ret = jffs2_do_readpage_nolock(inode, pg); 214ced22070SDavid Woodhouse mutex_unlock(&f->sem); 215205c109aSNick Piggin if (ret) 216205c109aSNick Piggin goto out_page; 2171da177e4SLinus Torvalds } 218205c109aSNick Piggin D1(printk(KERN_DEBUG "end write_begin(). pg->flags %lx\n", pg->flags)); 219205c109aSNick Piggin return ret; 220205c109aSNick Piggin 221205c109aSNick Piggin out_page: 222205c109aSNick Piggin unlock_page(pg); 223205c109aSNick Piggin page_cache_release(pg); 2241da177e4SLinus Torvalds return ret; 2251da177e4SLinus Torvalds } 2261da177e4SLinus Torvalds 227205c109aSNick Piggin static int jffs2_write_end(struct file *filp, struct address_space *mapping, 228205c109aSNick Piggin loff_t pos, unsigned len, unsigned copied, 229205c109aSNick Piggin struct page *pg, void *fsdata) 2301da177e4SLinus Torvalds { 2311da177e4SLinus Torvalds /* Actually commit the write from the page cache page we're looking at. 2321da177e4SLinus Torvalds * For now, we write the full page out each time. It sucks, but it's simple 2331da177e4SLinus Torvalds */ 234205c109aSNick Piggin struct inode *inode = mapping->host; 2351da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 2361da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 2371da177e4SLinus Torvalds struct jffs2_raw_inode *ri; 238205c109aSNick Piggin unsigned start = pos & (PAGE_CACHE_SIZE - 1); 239205c109aSNick Piggin unsigned end = start + copied; 2401da177e4SLinus Torvalds unsigned aligned_start = start & ~3; 2411da177e4SLinus Torvalds int ret = 0; 2421da177e4SLinus Torvalds uint32_t writtenlen = 0; 2431da177e4SLinus Torvalds 244205c109aSNick Piggin D1(printk(KERN_DEBUG "jffs2_write_end(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n", 2451da177e4SLinus Torvalds inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, pg->flags)); 2461da177e4SLinus Torvalds 2471da177e4SLinus Torvalds /* We need to avoid deadlock with page_cache_read() in 248205c109aSNick Piggin jffs2_garbage_collect_pass(). So the page must be 249205c109aSNick Piggin up to date to prevent page_cache_read() from trying 250205c109aSNick Piggin to re-lock it. */ 251205c109aSNick Piggin BUG_ON(!PageUptodate(pg)); 252205c109aSNick Piggin 253205c109aSNick Piggin if (end == PAGE_CACHE_SIZE) { 254cf5eba53SDavid Woodhouse /* When writing out the end of a page, write out the 255cf5eba53SDavid Woodhouse _whole_ page. This helps to reduce the number of 256cf5eba53SDavid Woodhouse nodes in files which have many short writes, like 257cf5eba53SDavid Woodhouse syslog files. */ 2582a754b51SNick Piggin aligned_start = 0; 259cf5eba53SDavid Woodhouse } 2601da177e4SLinus Torvalds 2611da177e4SLinus Torvalds ri = jffs2_alloc_raw_inode(); 2621da177e4SLinus Torvalds 2631da177e4SLinus Torvalds if (!ri) { 264205c109aSNick Piggin D1(printk(KERN_DEBUG "jffs2_write_end(): Allocation of raw inode failed\n")); 265205c109aSNick Piggin unlock_page(pg); 266205c109aSNick Piggin page_cache_release(pg); 2671da177e4SLinus Torvalds return -ENOMEM; 2681da177e4SLinus Torvalds } 2691da177e4SLinus Torvalds 2701da177e4SLinus Torvalds /* Set the fields that the generic jffs2_write_inode_range() code can't find */ 2711da177e4SLinus Torvalds ri->ino = cpu_to_je32(inode->i_ino); 2721da177e4SLinus Torvalds ri->mode = cpu_to_jemode(inode->i_mode); 2731da177e4SLinus Torvalds ri->uid = cpu_to_je16(inode->i_uid); 2741da177e4SLinus Torvalds ri->gid = cpu_to_je16(inode->i_gid); 2751da177e4SLinus Torvalds ri->isize = cpu_to_je32((uint32_t)inode->i_size); 2761da177e4SLinus Torvalds ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds()); 2771da177e4SLinus Torvalds 2781da177e4SLinus Torvalds /* In 2.4, it was already kmapped by generic_file_write(). Doesn't 2791da177e4SLinus Torvalds hurt to do it again. The alternative is ifdefs, which are ugly. */ 2801da177e4SLinus Torvalds kmap(pg); 2811da177e4SLinus Torvalds 2821da177e4SLinus Torvalds ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start, 2831da177e4SLinus Torvalds (pg->index << PAGE_CACHE_SHIFT) + aligned_start, 2841da177e4SLinus Torvalds end - aligned_start, &writtenlen); 2851da177e4SLinus Torvalds 2861da177e4SLinus Torvalds kunmap(pg); 2871da177e4SLinus Torvalds 2881da177e4SLinus Torvalds if (ret) { 2891da177e4SLinus Torvalds /* There was an error writing. */ 2901da177e4SLinus Torvalds SetPageError(pg); 2911da177e4SLinus Torvalds } 2921da177e4SLinus Torvalds 2931da177e4SLinus Torvalds /* Adjust writtenlen for the padding we did, so we don't confuse our caller */ 2942a754b51SNick Piggin writtenlen -= min(writtenlen, (start - aligned_start)); 2951da177e4SLinus Torvalds 2961da177e4SLinus Torvalds if (writtenlen) { 2972a754b51SNick Piggin if (inode->i_size < pos + writtenlen) { 2982a754b51SNick Piggin inode->i_size = pos + writtenlen; 2991da177e4SLinus Torvalds inode->i_blocks = (inode->i_size + 511) >> 9; 3001da177e4SLinus Torvalds 3011da177e4SLinus Torvalds inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime)); 3021da177e4SLinus Torvalds } 3031da177e4SLinus Torvalds } 3041da177e4SLinus Torvalds 3051da177e4SLinus Torvalds jffs2_free_raw_inode(ri); 3061da177e4SLinus Torvalds 3071da177e4SLinus Torvalds if (start+writtenlen < end) { 3081da177e4SLinus Torvalds /* generic_file_write has written more to the page cache than we've 3091da177e4SLinus Torvalds actually written to the medium. Mark the page !Uptodate so that 3101da177e4SLinus Torvalds it gets reread */ 311205c109aSNick Piggin D1(printk(KERN_DEBUG "jffs2_write_end(): Not all bytes written. Marking page !uptodate\n")); 3121da177e4SLinus Torvalds SetPageError(pg); 3131da177e4SLinus Torvalds ClearPageUptodate(pg); 3141da177e4SLinus Torvalds } 3151da177e4SLinus Torvalds 316205c109aSNick Piggin D1(printk(KERN_DEBUG "jffs2_write_end() returning %d\n", 317205c109aSNick Piggin writtenlen > 0 ? writtenlen : ret)); 318205c109aSNick Piggin unlock_page(pg); 319205c109aSNick Piggin page_cache_release(pg); 320205c109aSNick Piggin return writtenlen > 0 ? writtenlen : ret; 3211da177e4SLinus Torvalds } 322