11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * JFFS2 -- Journalling Flash File System, Version 2. 31da177e4SLinus Torvalds * 41da177e4SLinus Torvalds * Copyright (C) 2001-2003 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 * $Id: file.c,v 1.99 2004/11/16 20:36:11 dwmw2 Exp $ 111da177e4SLinus Torvalds * 121da177e4SLinus Torvalds */ 131da177e4SLinus Torvalds 141da177e4SLinus Torvalds #include <linux/version.h> 151da177e4SLinus Torvalds #include <linux/kernel.h> 161da177e4SLinus Torvalds #include <linux/slab.h> 171da177e4SLinus Torvalds #include <linux/fs.h> 181da177e4SLinus Torvalds #include <linux/time.h> 191da177e4SLinus Torvalds #include <linux/pagemap.h> 201da177e4SLinus Torvalds #include <linux/highmem.h> 211da177e4SLinus Torvalds #include <linux/crc32.h> 221da177e4SLinus Torvalds #include <linux/jffs2.h> 231da177e4SLinus Torvalds #include "nodelist.h" 241da177e4SLinus Torvalds 251da177e4SLinus Torvalds extern int generic_file_open(struct inode *, struct file *) __attribute__((weak)); 261da177e4SLinus Torvalds extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin) __attribute__((weak)); 271da177e4SLinus Torvalds 281da177e4SLinus Torvalds static int jffs2_commit_write (struct file *filp, struct page *pg, 291da177e4SLinus Torvalds unsigned start, unsigned end); 301da177e4SLinus Torvalds static int jffs2_prepare_write (struct file *filp, struct page *pg, 311da177e4SLinus Torvalds unsigned start, unsigned end); 321da177e4SLinus Torvalds static int jffs2_readpage (struct file *filp, struct page *pg); 331da177e4SLinus Torvalds 341da177e4SLinus Torvalds int jffs2_fsync(struct file *filp, struct dentry *dentry, int datasync) 351da177e4SLinus Torvalds { 361da177e4SLinus Torvalds struct inode *inode = dentry->d_inode; 371da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 381da177e4SLinus Torvalds 391da177e4SLinus Torvalds /* Trigger GC to flush any pending writes for this inode */ 401da177e4SLinus Torvalds jffs2_flush_wbuf_gc(c, inode->i_ino); 411da177e4SLinus Torvalds 421da177e4SLinus Torvalds return 0; 431da177e4SLinus Torvalds } 441da177e4SLinus Torvalds 451da177e4SLinus Torvalds struct file_operations jffs2_file_operations = 461da177e4SLinus Torvalds { 471da177e4SLinus Torvalds .llseek = generic_file_llseek, 481da177e4SLinus Torvalds .open = generic_file_open, 491da177e4SLinus Torvalds .read = generic_file_read, 501da177e4SLinus Torvalds .write = generic_file_write, 511da177e4SLinus Torvalds .ioctl = jffs2_ioctl, 521da177e4SLinus Torvalds .mmap = generic_file_readonly_mmap, 531da177e4SLinus Torvalds .fsync = jffs2_fsync, 541da177e4SLinus Torvalds #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,29) 551da177e4SLinus Torvalds .sendfile = generic_file_sendfile 561da177e4SLinus Torvalds #endif 571da177e4SLinus Torvalds }; 581da177e4SLinus Torvalds 591da177e4SLinus Torvalds /* jffs2_file_inode_operations */ 601da177e4SLinus Torvalds 611da177e4SLinus Torvalds struct inode_operations jffs2_file_inode_operations = 621da177e4SLinus Torvalds { 631da177e4SLinus Torvalds .setattr = jffs2_setattr 641da177e4SLinus Torvalds }; 651da177e4SLinus Torvalds 661da177e4SLinus Torvalds struct address_space_operations jffs2_file_address_operations = 671da177e4SLinus Torvalds { 681da177e4SLinus Torvalds .readpage = jffs2_readpage, 691da177e4SLinus Torvalds .prepare_write =jffs2_prepare_write, 701da177e4SLinus Torvalds .commit_write = jffs2_commit_write 711da177e4SLinus Torvalds }; 721da177e4SLinus Torvalds 731da177e4SLinus Torvalds static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg) 741da177e4SLinus Torvalds { 751da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 761da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 771da177e4SLinus Torvalds unsigned char *pg_buf; 781da177e4SLinus Torvalds int ret; 791da177e4SLinus Torvalds 801da177e4SLinus 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)); 811da177e4SLinus Torvalds 82cd7619d6SMatt Mackall BUG_ON(!PageLocked(pg)); 831da177e4SLinus Torvalds 841da177e4SLinus Torvalds pg_buf = kmap(pg); 851da177e4SLinus Torvalds /* FIXME: Can kmap fail? */ 861da177e4SLinus Torvalds 871da177e4SLinus Torvalds ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE); 881da177e4SLinus Torvalds 891da177e4SLinus Torvalds if (ret) { 901da177e4SLinus Torvalds ClearPageUptodate(pg); 911da177e4SLinus Torvalds SetPageError(pg); 921da177e4SLinus Torvalds } else { 931da177e4SLinus Torvalds SetPageUptodate(pg); 941da177e4SLinus Torvalds ClearPageError(pg); 951da177e4SLinus Torvalds } 961da177e4SLinus Torvalds 971da177e4SLinus Torvalds flush_dcache_page(pg); 981da177e4SLinus Torvalds kunmap(pg); 991da177e4SLinus Torvalds 1001da177e4SLinus Torvalds D2(printk(KERN_DEBUG "readpage finished\n")); 1011da177e4SLinus Torvalds return 0; 1021da177e4SLinus Torvalds } 1031da177e4SLinus Torvalds 1041da177e4SLinus Torvalds int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg) 1051da177e4SLinus Torvalds { 1061da177e4SLinus Torvalds int ret = jffs2_do_readpage_nolock(inode, pg); 1071da177e4SLinus Torvalds unlock_page(pg); 1081da177e4SLinus Torvalds return ret; 1091da177e4SLinus Torvalds } 1101da177e4SLinus Torvalds 1111da177e4SLinus Torvalds 1121da177e4SLinus Torvalds static int jffs2_readpage (struct file *filp, struct page *pg) 1131da177e4SLinus Torvalds { 1141da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host); 1151da177e4SLinus Torvalds int ret; 1161da177e4SLinus Torvalds 1171da177e4SLinus Torvalds down(&f->sem); 1181da177e4SLinus Torvalds ret = jffs2_do_readpage_unlock(pg->mapping->host, pg); 1191da177e4SLinus Torvalds up(&f->sem); 1201da177e4SLinus Torvalds return ret; 1211da177e4SLinus Torvalds } 1221da177e4SLinus Torvalds 1231da177e4SLinus Torvalds static int jffs2_prepare_write (struct file *filp, struct page *pg, 1241da177e4SLinus Torvalds unsigned start, unsigned end) 1251da177e4SLinus Torvalds { 1261da177e4SLinus Torvalds struct inode *inode = pg->mapping->host; 1271da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 1281da177e4SLinus Torvalds uint32_t pageofs = pg->index << PAGE_CACHE_SHIFT; 1291da177e4SLinus Torvalds int ret = 0; 1301da177e4SLinus Torvalds 1311da177e4SLinus Torvalds D1(printk(KERN_DEBUG "jffs2_prepare_write()\n")); 1321da177e4SLinus Torvalds 1331da177e4SLinus Torvalds if (pageofs > inode->i_size) { 1341da177e4SLinus Torvalds /* Make new hole frag from old EOF to new page */ 1351da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 1361da177e4SLinus Torvalds struct jffs2_raw_inode ri; 1371da177e4SLinus Torvalds struct jffs2_full_dnode *fn; 1381da177e4SLinus Torvalds uint32_t phys_ofs, alloc_len; 1391da177e4SLinus Torvalds 1401da177e4SLinus Torvalds D1(printk(KERN_DEBUG "Writing new hole frag 0x%x-0x%x between current EOF and new page\n", 1411da177e4SLinus Torvalds (unsigned int)inode->i_size, pageofs)); 1421da177e4SLinus Torvalds 1431da177e4SLinus Torvalds ret = jffs2_reserve_space(c, sizeof(ri), &phys_ofs, &alloc_len, ALLOC_NORMAL); 1441da177e4SLinus Torvalds if (ret) 1451da177e4SLinus Torvalds return ret; 1461da177e4SLinus Torvalds 1471da177e4SLinus Torvalds down(&f->sem); 1481da177e4SLinus Torvalds memset(&ri, 0, sizeof(ri)); 1491da177e4SLinus Torvalds 1501da177e4SLinus Torvalds ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 1511da177e4SLinus Torvalds ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 1521da177e4SLinus Torvalds ri.totlen = cpu_to_je32(sizeof(ri)); 1531da177e4SLinus Torvalds ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 1541da177e4SLinus Torvalds 1551da177e4SLinus Torvalds ri.ino = cpu_to_je32(f->inocache->ino); 1561da177e4SLinus Torvalds ri.version = cpu_to_je32(++f->highest_version); 1571da177e4SLinus Torvalds ri.mode = cpu_to_jemode(inode->i_mode); 1581da177e4SLinus Torvalds ri.uid = cpu_to_je16(inode->i_uid); 1591da177e4SLinus Torvalds ri.gid = cpu_to_je16(inode->i_gid); 1601da177e4SLinus Torvalds ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs)); 1611da177e4SLinus Torvalds ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds()); 1621da177e4SLinus Torvalds ri.offset = cpu_to_je32(inode->i_size); 1631da177e4SLinus Torvalds ri.dsize = cpu_to_je32(pageofs - inode->i_size); 1641da177e4SLinus Torvalds ri.csize = cpu_to_je32(0); 1651da177e4SLinus Torvalds ri.compr = JFFS2_COMPR_ZERO; 1661da177e4SLinus Torvalds ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 1671da177e4SLinus Torvalds ri.data_crc = cpu_to_je32(0); 1681da177e4SLinus Torvalds 1691da177e4SLinus Torvalds fn = jffs2_write_dnode(c, f, &ri, NULL, 0, phys_ofs, ALLOC_NORMAL); 1701da177e4SLinus Torvalds 1711da177e4SLinus Torvalds if (IS_ERR(fn)) { 1721da177e4SLinus Torvalds ret = PTR_ERR(fn); 1731da177e4SLinus Torvalds jffs2_complete_reservation(c); 1741da177e4SLinus Torvalds up(&f->sem); 1751da177e4SLinus Torvalds return ret; 1761da177e4SLinus Torvalds } 1771da177e4SLinus Torvalds ret = jffs2_add_full_dnode_to_inode(c, f, fn); 1781da177e4SLinus Torvalds if (f->metadata) { 1791da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, f->metadata->raw); 1801da177e4SLinus Torvalds jffs2_free_full_dnode(f->metadata); 1811da177e4SLinus Torvalds f->metadata = NULL; 1821da177e4SLinus Torvalds } 1831da177e4SLinus Torvalds if (ret) { 1841da177e4SLinus Torvalds D1(printk(KERN_DEBUG "Eep. add_full_dnode_to_inode() failed in prepare_write, returned %d\n", ret)); 1851da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, fn->raw); 1861da177e4SLinus Torvalds jffs2_free_full_dnode(fn); 1871da177e4SLinus Torvalds jffs2_complete_reservation(c); 1881da177e4SLinus Torvalds up(&f->sem); 1891da177e4SLinus Torvalds return ret; 1901da177e4SLinus Torvalds } 1911da177e4SLinus Torvalds jffs2_complete_reservation(c); 1921da177e4SLinus Torvalds inode->i_size = pageofs; 1931da177e4SLinus Torvalds up(&f->sem); 1941da177e4SLinus Torvalds } 1951da177e4SLinus Torvalds 1961da177e4SLinus Torvalds /* Read in the page if it wasn't already present, unless it's a whole page */ 1971da177e4SLinus Torvalds if (!PageUptodate(pg) && (start || end < PAGE_CACHE_SIZE)) { 1981da177e4SLinus Torvalds down(&f->sem); 1991da177e4SLinus Torvalds ret = jffs2_do_readpage_nolock(inode, pg); 2001da177e4SLinus Torvalds up(&f->sem); 2011da177e4SLinus Torvalds } 2021da177e4SLinus Torvalds D1(printk(KERN_DEBUG "end prepare_write(). pg->flags %lx\n", pg->flags)); 2031da177e4SLinus Torvalds return ret; 2041da177e4SLinus Torvalds } 2051da177e4SLinus Torvalds 2061da177e4SLinus Torvalds static int jffs2_commit_write (struct file *filp, struct page *pg, 2071da177e4SLinus Torvalds unsigned start, unsigned end) 2081da177e4SLinus Torvalds { 2091da177e4SLinus Torvalds /* Actually commit the write from the page cache page we're looking at. 2101da177e4SLinus Torvalds * For now, we write the full page out each time. It sucks, but it's simple 2111da177e4SLinus Torvalds */ 2121da177e4SLinus Torvalds struct inode *inode = pg->mapping->host; 2131da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 2141da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 2151da177e4SLinus Torvalds struct jffs2_raw_inode *ri; 2161da177e4SLinus Torvalds unsigned aligned_start = start & ~3; 2171da177e4SLinus Torvalds int ret = 0; 2181da177e4SLinus Torvalds uint32_t writtenlen = 0; 2191da177e4SLinus Torvalds 2201da177e4SLinus Torvalds D1(printk(KERN_DEBUG "jffs2_commit_write(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n", 2211da177e4SLinus Torvalds inode->i_ino, pg->index << PAGE_CACHE_SHIFT, start, end, pg->flags)); 2221da177e4SLinus Torvalds 2231da177e4SLinus Torvalds if (!start && end == PAGE_CACHE_SIZE) { 2241da177e4SLinus Torvalds /* We need to avoid deadlock with page_cache_read() in 2251da177e4SLinus Torvalds jffs2_garbage_collect_pass(). So we have to mark the 2261da177e4SLinus Torvalds page up to date, to prevent page_cache_read() from 2271da177e4SLinus Torvalds trying to re-lock it. */ 2281da177e4SLinus Torvalds SetPageUptodate(pg); 2291da177e4SLinus Torvalds } 2301da177e4SLinus Torvalds 2311da177e4SLinus Torvalds ri = jffs2_alloc_raw_inode(); 2321da177e4SLinus Torvalds 2331da177e4SLinus Torvalds if (!ri) { 2341da177e4SLinus Torvalds D1(printk(KERN_DEBUG "jffs2_commit_write(): Allocation of raw inode failed\n")); 2351da177e4SLinus Torvalds return -ENOMEM; 2361da177e4SLinus Torvalds } 2371da177e4SLinus Torvalds 2381da177e4SLinus Torvalds /* Set the fields that the generic jffs2_write_inode_range() code can't find */ 2391da177e4SLinus Torvalds ri->ino = cpu_to_je32(inode->i_ino); 2401da177e4SLinus Torvalds ri->mode = cpu_to_jemode(inode->i_mode); 2411da177e4SLinus Torvalds ri->uid = cpu_to_je16(inode->i_uid); 2421da177e4SLinus Torvalds ri->gid = cpu_to_je16(inode->i_gid); 2431da177e4SLinus Torvalds ri->isize = cpu_to_je32((uint32_t)inode->i_size); 2441da177e4SLinus Torvalds ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds()); 2451da177e4SLinus Torvalds 2461da177e4SLinus Torvalds /* In 2.4, it was already kmapped by generic_file_write(). Doesn't 2471da177e4SLinus Torvalds hurt to do it again. The alternative is ifdefs, which are ugly. */ 2481da177e4SLinus Torvalds kmap(pg); 2491da177e4SLinus Torvalds 2501da177e4SLinus Torvalds ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start, 2511da177e4SLinus Torvalds (pg->index << PAGE_CACHE_SHIFT) + aligned_start, 2521da177e4SLinus Torvalds end - aligned_start, &writtenlen); 2531da177e4SLinus Torvalds 2541da177e4SLinus Torvalds kunmap(pg); 2551da177e4SLinus Torvalds 2561da177e4SLinus Torvalds if (ret) { 2571da177e4SLinus Torvalds /* There was an error writing. */ 2581da177e4SLinus Torvalds SetPageError(pg); 2591da177e4SLinus Torvalds } 2601da177e4SLinus Torvalds 2611da177e4SLinus Torvalds /* Adjust writtenlen for the padding we did, so we don't confuse our caller */ 2621da177e4SLinus Torvalds if (writtenlen < (start&3)) 2631da177e4SLinus Torvalds writtenlen = 0; 2641da177e4SLinus Torvalds else 2651da177e4SLinus Torvalds writtenlen -= (start&3); 2661da177e4SLinus Torvalds 2671da177e4SLinus Torvalds if (writtenlen) { 2681da177e4SLinus Torvalds if (inode->i_size < (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen) { 2691da177e4SLinus Torvalds inode->i_size = (pg->index << PAGE_CACHE_SHIFT) + start + writtenlen; 2701da177e4SLinus Torvalds inode->i_blocks = (inode->i_size + 511) >> 9; 2711da177e4SLinus Torvalds 2721da177e4SLinus Torvalds inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime)); 2731da177e4SLinus Torvalds } 2741da177e4SLinus Torvalds } 2751da177e4SLinus Torvalds 2761da177e4SLinus Torvalds jffs2_free_raw_inode(ri); 2771da177e4SLinus Torvalds 2781da177e4SLinus Torvalds if (start+writtenlen < end) { 2791da177e4SLinus Torvalds /* generic_file_write has written more to the page cache than we've 2801da177e4SLinus Torvalds actually written to the medium. Mark the page !Uptodate so that 2811da177e4SLinus Torvalds it gets reread */ 2821da177e4SLinus Torvalds D1(printk(KERN_DEBUG "jffs2_commit_write(): Not all bytes written. Marking page !uptodate\n")); 2831da177e4SLinus Torvalds SetPageError(pg); 2841da177e4SLinus Torvalds ClearPageUptodate(pg); 2851da177e4SLinus Torvalds } 2861da177e4SLinus Torvalds 2871da177e4SLinus Torvalds D1(printk(KERN_DEBUG "jffs2_commit_write() returning %d\n",writtenlen?writtenlen:ret)); 2881da177e4SLinus Torvalds return writtenlen?writtenlen:ret; 2891da177e4SLinus Torvalds } 290