11da177e4SLinus Torvalds /* 21da177e4SLinus Torvalds * JFFS2 -- Journalling Flash File System, Version 2. 31da177e4SLinus Torvalds * 4c00c310eSDavid Woodhouse * Copyright © 2001-2007 Red Hat, Inc. 56088c058SDavid Woodhouse * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org> 61da177e4SLinus Torvalds * 71da177e4SLinus Torvalds * Created by David Woodhouse <dwmw2@infradead.org> 81da177e4SLinus Torvalds * 91da177e4SLinus Torvalds * For licensing information, see the file 'LICENCE' in this directory. 101da177e4SLinus Torvalds * 111da177e4SLinus Torvalds */ 121da177e4SLinus Torvalds 135a528957SJoe Perches #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 145a528957SJoe Perches 151da177e4SLinus Torvalds #include <linux/kernel.h> 161da177e4SLinus Torvalds #include <linux/fs.h> 171da177e4SLinus Torvalds #include <linux/time.h> 181da177e4SLinus Torvalds #include <linux/pagemap.h> 191da177e4SLinus Torvalds #include <linux/highmem.h> 201da177e4SLinus Torvalds #include <linux/crc32.h> 211da177e4SLinus Torvalds #include <linux/jffs2.h> 221da177e4SLinus Torvalds #include "nodelist.h" 231da177e4SLinus Torvalds 24205c109aSNick Piggin static int jffs2_write_end(struct file *filp, struct address_space *mapping, 25205c109aSNick Piggin loff_t pos, unsigned len, unsigned copied, 26205c109aSNick Piggin struct page *pg, void *fsdata); 27205c109aSNick Piggin static int jffs2_write_begin(struct file *filp, struct address_space *mapping, 28205c109aSNick Piggin loff_t pos, unsigned len, unsigned flags, 29205c109aSNick Piggin struct page **pagep, void **fsdata); 301da177e4SLinus Torvalds static int jffs2_readpage (struct file *filp, struct page *pg); 311da177e4SLinus Torvalds 3202c24a82SJosef Bacik int jffs2_fsync(struct file *filp, loff_t start, loff_t end, int datasync) 331da177e4SLinus Torvalds { 347ea80859SChristoph Hellwig struct inode *inode = filp->f_mapping->host; 351da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 3602c24a82SJosef Bacik int ret; 371da177e4SLinus Torvalds 3802c24a82SJosef Bacik ret = filemap_write_and_wait_range(inode->i_mapping, start, end); 3902c24a82SJosef Bacik if (ret) 4002c24a82SJosef Bacik return ret; 4102c24a82SJosef Bacik 425955102cSAl Viro inode_lock(inode); 431da177e4SLinus Torvalds /* Trigger GC to flush any pending writes for this inode */ 441da177e4SLinus Torvalds jffs2_flush_wbuf_gc(c, inode->i_ino); 455955102cSAl Viro inode_unlock(inode); 461da177e4SLinus Torvalds 471da177e4SLinus Torvalds return 0; 481da177e4SLinus Torvalds } 491da177e4SLinus Torvalds 504b6f5d20SArjan van de Ven const struct file_operations jffs2_file_operations = 511da177e4SLinus Torvalds { 521da177e4SLinus Torvalds .llseek = generic_file_llseek, 531da177e4SLinus Torvalds .open = generic_file_open, 54aad4f8bbSAl Viro .read_iter = generic_file_read_iter, 558174202bSAl Viro .write_iter = generic_file_write_iter, 560533400bSStoyan Gaydarov .unlocked_ioctl=jffs2_ioctl, 571da177e4SLinus Torvalds .mmap = generic_file_readonly_mmap, 581da177e4SLinus Torvalds .fsync = jffs2_fsync, 595ffc4ef4SJens Axboe .splice_read = generic_file_splice_read, 601da177e4SLinus Torvalds }; 611da177e4SLinus Torvalds 621da177e4SLinus Torvalds /* jffs2_file_inode_operations */ 631da177e4SLinus Torvalds 6492e1d5beSArjan van de Ven const struct inode_operations jffs2_file_inode_operations = 651da177e4SLinus Torvalds { 664e34e719SChristoph Hellwig .get_acl = jffs2_get_acl, 67f2963d45SChristoph Hellwig .set_acl = jffs2_set_acl, 68aa98d7cfSKaiGai Kohei .setattr = jffs2_setattr, 69aa98d7cfSKaiGai Kohei .setxattr = jffs2_setxattr, 70aa98d7cfSKaiGai Kohei .getxattr = jffs2_getxattr, 71aa98d7cfSKaiGai Kohei .listxattr = jffs2_listxattr, 72aa98d7cfSKaiGai Kohei .removexattr = jffs2_removexattr 731da177e4SLinus Torvalds }; 741da177e4SLinus Torvalds 75f5e54d6eSChristoph Hellwig const struct address_space_operations jffs2_file_address_operations = 761da177e4SLinus Torvalds { 771da177e4SLinus Torvalds .readpage = jffs2_readpage, 78205c109aSNick Piggin .write_begin = jffs2_write_begin, 79205c109aSNick Piggin .write_end = jffs2_write_end, 801da177e4SLinus Torvalds }; 811da177e4SLinus Torvalds 821da177e4SLinus Torvalds static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg) 831da177e4SLinus Torvalds { 841da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 851da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 861da177e4SLinus Torvalds unsigned char *pg_buf; 871da177e4SLinus Torvalds int ret; 881da177e4SLinus Torvalds 899c261b33SJoe Perches jffs2_dbg(2, "%s(): ino #%lu, page at offset 0x%lx\n", 909c261b33SJoe Perches __func__, inode->i_ino, pg->index << PAGE_CACHE_SHIFT); 911da177e4SLinus Torvalds 92cd7619d6SMatt Mackall BUG_ON(!PageLocked(pg)); 931da177e4SLinus Torvalds 941da177e4SLinus Torvalds pg_buf = kmap(pg); 951da177e4SLinus Torvalds /* FIXME: Can kmap fail? */ 961da177e4SLinus Torvalds 971da177e4SLinus Torvalds ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE); 981da177e4SLinus Torvalds 991da177e4SLinus Torvalds if (ret) { 1001da177e4SLinus Torvalds ClearPageUptodate(pg); 1011da177e4SLinus Torvalds SetPageError(pg); 1021da177e4SLinus Torvalds } else { 1031da177e4SLinus Torvalds SetPageUptodate(pg); 1041da177e4SLinus Torvalds ClearPageError(pg); 1051da177e4SLinus Torvalds } 1061da177e4SLinus Torvalds 1071da177e4SLinus Torvalds flush_dcache_page(pg); 1081da177e4SLinus Torvalds kunmap(pg); 1091da177e4SLinus Torvalds 1109c261b33SJoe Perches jffs2_dbg(2, "readpage finished\n"); 11157ca7debSAnders Grafström return ret; 1121da177e4SLinus Torvalds } 1131da177e4SLinus Torvalds 1141da177e4SLinus Torvalds int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg) 1151da177e4SLinus Torvalds { 1161da177e4SLinus Torvalds int ret = jffs2_do_readpage_nolock(inode, pg); 1171da177e4SLinus Torvalds unlock_page(pg); 1181da177e4SLinus Torvalds return ret; 1191da177e4SLinus Torvalds } 1201da177e4SLinus Torvalds 1211da177e4SLinus Torvalds 1221da177e4SLinus Torvalds static int jffs2_readpage (struct file *filp, struct page *pg) 1231da177e4SLinus Torvalds { 1241da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host); 1251da177e4SLinus Torvalds int ret; 1261da177e4SLinus Torvalds 127ced22070SDavid Woodhouse mutex_lock(&f->sem); 1281da177e4SLinus Torvalds ret = jffs2_do_readpage_unlock(pg->mapping->host, pg); 129ced22070SDavid Woodhouse mutex_unlock(&f->sem); 1301da177e4SLinus Torvalds return ret; 1311da177e4SLinus Torvalds } 1321da177e4SLinus Torvalds 133205c109aSNick Piggin static int jffs2_write_begin(struct file *filp, struct address_space *mapping, 134205c109aSNick Piggin loff_t pos, unsigned len, unsigned flags, 135205c109aSNick Piggin struct page **pagep, void **fsdata) 1361da177e4SLinus Torvalds { 137205c109aSNick Piggin struct page *pg; 138205c109aSNick Piggin struct inode *inode = mapping->host; 1391da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 140205c109aSNick Piggin pgoff_t index = pos >> PAGE_CACHE_SHIFT; 141abe2f414SAlexey Korolev uint32_t pageofs = index << PAGE_CACHE_SHIFT; 1421da177e4SLinus Torvalds int ret = 0; 1431da177e4SLinus Torvalds 144157078f6SThomas Betker pg = grab_cache_page_write_begin(mapping, index, flags); 145157078f6SThomas Betker if (!pg) 146157078f6SThomas Betker return -ENOMEM; 147157078f6SThomas Betker *pagep = pg; 148157078f6SThomas Betker 1499c261b33SJoe Perches jffs2_dbg(1, "%s()\n", __func__); 1501da177e4SLinus Torvalds 1511da177e4SLinus Torvalds if (pageofs > inode->i_size) { 1521da177e4SLinus Torvalds /* Make new hole frag from old EOF to new page */ 153157078f6SThomas Betker struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 154157078f6SThomas Betker struct jffs2_raw_inode ri; 1551da177e4SLinus Torvalds struct jffs2_full_dnode *fn; 156157078f6SThomas Betker uint32_t alloc_len; 1571da177e4SLinus Torvalds 1589c261b33SJoe Perches jffs2_dbg(1, "Writing new hole frag 0x%x-0x%x between current EOF and new page\n", 1599c261b33SJoe Perches (unsigned int)inode->i_size, pageofs); 1601da177e4SLinus Torvalds 161157078f6SThomas Betker ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len, 162157078f6SThomas Betker ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE); 163157078f6SThomas Betker if (ret) 164157078f6SThomas Betker goto out_page; 165157078f6SThomas Betker 166157078f6SThomas Betker mutex_lock(&f->sem); 1671da177e4SLinus Torvalds memset(&ri, 0, sizeof(ri)); 1681da177e4SLinus Torvalds 1691da177e4SLinus Torvalds ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 1701da177e4SLinus Torvalds ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 1711da177e4SLinus Torvalds ri.totlen = cpu_to_je32(sizeof(ri)); 1721da177e4SLinus Torvalds ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 1731da177e4SLinus Torvalds 1741da177e4SLinus Torvalds ri.ino = cpu_to_je32(f->inocache->ino); 1751da177e4SLinus Torvalds ri.version = cpu_to_je32(++f->highest_version); 1761da177e4SLinus Torvalds ri.mode = cpu_to_jemode(inode->i_mode); 1770cfe53d3SEric W. Biederman ri.uid = cpu_to_je16(i_uid_read(inode)); 1780cfe53d3SEric W. Biederman ri.gid = cpu_to_je16(i_gid_read(inode)); 1791da177e4SLinus Torvalds ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs)); 1801da177e4SLinus Torvalds ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds()); 1811da177e4SLinus Torvalds ri.offset = cpu_to_je32(inode->i_size); 1821da177e4SLinus Torvalds ri.dsize = cpu_to_je32(pageofs - inode->i_size); 1831da177e4SLinus Torvalds ri.csize = cpu_to_je32(0); 1841da177e4SLinus Torvalds ri.compr = JFFS2_COMPR_ZERO; 1851da177e4SLinus Torvalds ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 1861da177e4SLinus Torvalds ri.data_crc = cpu_to_je32(0); 1871da177e4SLinus Torvalds 1889fe4854cSDavid Woodhouse fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL); 1891da177e4SLinus Torvalds 1901da177e4SLinus Torvalds if (IS_ERR(fn)) { 1911da177e4SLinus Torvalds ret = PTR_ERR(fn); 1921da177e4SLinus Torvalds jffs2_complete_reservation(c); 193157078f6SThomas Betker mutex_unlock(&f->sem); 194205c109aSNick Piggin goto out_page; 1951da177e4SLinus Torvalds } 1961da177e4SLinus Torvalds ret = jffs2_add_full_dnode_to_inode(c, f, fn); 1971da177e4SLinus Torvalds if (f->metadata) { 1981da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, f->metadata->raw); 1991da177e4SLinus Torvalds jffs2_free_full_dnode(f->metadata); 2001da177e4SLinus Torvalds f->metadata = NULL; 2011da177e4SLinus Torvalds } 2021da177e4SLinus Torvalds if (ret) { 2039c261b33SJoe Perches jffs2_dbg(1, "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n", 2049c261b33SJoe Perches ret); 2051da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, fn->raw); 2061da177e4SLinus Torvalds jffs2_free_full_dnode(fn); 2071da177e4SLinus Torvalds jffs2_complete_reservation(c); 208157078f6SThomas Betker mutex_unlock(&f->sem); 209205c109aSNick Piggin goto out_page; 2101da177e4SLinus Torvalds } 2111da177e4SLinus Torvalds jffs2_complete_reservation(c); 2121da177e4SLinus Torvalds inode->i_size = pageofs; 213157078f6SThomas Betker mutex_unlock(&f->sem); 2141da177e4SLinus Torvalds } 2151da177e4SLinus Torvalds 216205c109aSNick Piggin /* 217205c109aSNick Piggin * Read in the page if it wasn't already present. Cannot optimize away 218205c109aSNick Piggin * the whole page write case until jffs2_write_end can handle the 219205c109aSNick Piggin * case of a short-copy. 220205c109aSNick Piggin */ 221205c109aSNick Piggin if (!PageUptodate(pg)) { 222157078f6SThomas Betker mutex_lock(&f->sem); 2231da177e4SLinus Torvalds ret = jffs2_do_readpage_nolock(inode, pg); 224157078f6SThomas Betker mutex_unlock(&f->sem); 225205c109aSNick Piggin if (ret) 226205c109aSNick Piggin goto out_page; 2271da177e4SLinus Torvalds } 2289c261b33SJoe Perches jffs2_dbg(1, "end write_begin(). pg->flags %lx\n", pg->flags); 229205c109aSNick Piggin return ret; 230205c109aSNick Piggin 231205c109aSNick Piggin out_page: 232205c109aSNick Piggin unlock_page(pg); 233205c109aSNick Piggin page_cache_release(pg); 2341da177e4SLinus Torvalds return ret; 2351da177e4SLinus Torvalds } 2361da177e4SLinus Torvalds 237205c109aSNick Piggin static int jffs2_write_end(struct file *filp, struct address_space *mapping, 238205c109aSNick Piggin loff_t pos, unsigned len, unsigned copied, 239205c109aSNick Piggin struct page *pg, void *fsdata) 2401da177e4SLinus Torvalds { 2411da177e4SLinus Torvalds /* Actually commit the write from the page cache page we're looking at. 2421da177e4SLinus Torvalds * For now, we write the full page out each time. It sucks, but it's simple 2431da177e4SLinus Torvalds */ 244205c109aSNick Piggin struct inode *inode = mapping->host; 2451da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 2461da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 2471da177e4SLinus Torvalds struct jffs2_raw_inode *ri; 248205c109aSNick Piggin unsigned start = pos & (PAGE_CACHE_SIZE - 1); 249205c109aSNick Piggin unsigned end = start + copied; 2501da177e4SLinus Torvalds unsigned aligned_start = start & ~3; 2511da177e4SLinus Torvalds int ret = 0; 2521da177e4SLinus Torvalds uint32_t writtenlen = 0; 2531da177e4SLinus Torvalds 2549c261b33SJoe Perches jffs2_dbg(1, "%s(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n", 2559c261b33SJoe Perches __func__, inode->i_ino, pg->index << PAGE_CACHE_SHIFT, 2569c261b33SJoe Perches start, end, pg->flags); 2571da177e4SLinus Torvalds 2581da177e4SLinus Torvalds /* We need to avoid deadlock with page_cache_read() in 259205c109aSNick Piggin jffs2_garbage_collect_pass(). So the page must be 260205c109aSNick Piggin up to date to prevent page_cache_read() from trying 261205c109aSNick Piggin to re-lock it. */ 262205c109aSNick Piggin BUG_ON(!PageUptodate(pg)); 263205c109aSNick Piggin 264205c109aSNick Piggin if (end == PAGE_CACHE_SIZE) { 265cf5eba53SDavid Woodhouse /* When writing out the end of a page, write out the 266cf5eba53SDavid Woodhouse _whole_ page. This helps to reduce the number of 267cf5eba53SDavid Woodhouse nodes in files which have many short writes, like 268cf5eba53SDavid Woodhouse syslog files. */ 2692a754b51SNick Piggin aligned_start = 0; 270cf5eba53SDavid Woodhouse } 2711da177e4SLinus Torvalds 2721da177e4SLinus Torvalds ri = jffs2_alloc_raw_inode(); 2731da177e4SLinus Torvalds 2741da177e4SLinus Torvalds if (!ri) { 2759c261b33SJoe Perches jffs2_dbg(1, "%s(): Allocation of raw inode failed\n", 2769c261b33SJoe Perches __func__); 277205c109aSNick Piggin unlock_page(pg); 278205c109aSNick Piggin page_cache_release(pg); 2791da177e4SLinus Torvalds return -ENOMEM; 2801da177e4SLinus Torvalds } 2811da177e4SLinus Torvalds 2821da177e4SLinus Torvalds /* Set the fields that the generic jffs2_write_inode_range() code can't find */ 2831da177e4SLinus Torvalds ri->ino = cpu_to_je32(inode->i_ino); 2841da177e4SLinus Torvalds ri->mode = cpu_to_jemode(inode->i_mode); 2850cfe53d3SEric W. Biederman ri->uid = cpu_to_je16(i_uid_read(inode)); 2860cfe53d3SEric W. Biederman ri->gid = cpu_to_je16(i_gid_read(inode)); 2871da177e4SLinus Torvalds ri->isize = cpu_to_je32((uint32_t)inode->i_size); 2881da177e4SLinus Torvalds ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds()); 2891da177e4SLinus Torvalds 2901da177e4SLinus Torvalds /* In 2.4, it was already kmapped by generic_file_write(). Doesn't 2911da177e4SLinus Torvalds hurt to do it again. The alternative is ifdefs, which are ugly. */ 2921da177e4SLinus Torvalds kmap(pg); 2931da177e4SLinus Torvalds 2941da177e4SLinus Torvalds ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start, 2951da177e4SLinus Torvalds (pg->index << PAGE_CACHE_SHIFT) + aligned_start, 2961da177e4SLinus Torvalds end - aligned_start, &writtenlen); 2971da177e4SLinus Torvalds 2981da177e4SLinus Torvalds kunmap(pg); 2991da177e4SLinus Torvalds 3001da177e4SLinus Torvalds if (ret) { 3011da177e4SLinus Torvalds /* There was an error writing. */ 3021da177e4SLinus Torvalds SetPageError(pg); 3031da177e4SLinus Torvalds } 3041da177e4SLinus Torvalds 3051da177e4SLinus Torvalds /* Adjust writtenlen for the padding we did, so we don't confuse our caller */ 3062a754b51SNick Piggin writtenlen -= min(writtenlen, (start - aligned_start)); 3071da177e4SLinus Torvalds 3081da177e4SLinus Torvalds if (writtenlen) { 3092a754b51SNick Piggin if (inode->i_size < pos + writtenlen) { 3102a754b51SNick Piggin inode->i_size = pos + writtenlen; 3111da177e4SLinus Torvalds inode->i_blocks = (inode->i_size + 511) >> 9; 3121da177e4SLinus Torvalds 3131da177e4SLinus Torvalds inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime)); 3141da177e4SLinus Torvalds } 3151da177e4SLinus Torvalds } 3161da177e4SLinus Torvalds 3171da177e4SLinus Torvalds jffs2_free_raw_inode(ri); 3181da177e4SLinus Torvalds 3191da177e4SLinus Torvalds if (start+writtenlen < end) { 3201da177e4SLinus Torvalds /* generic_file_write has written more to the page cache than we've 3211da177e4SLinus Torvalds actually written to the medium. Mark the page !Uptodate so that 3221da177e4SLinus Torvalds it gets reread */ 3239c261b33SJoe Perches jffs2_dbg(1, "%s(): Not all bytes written. Marking page !uptodate\n", 3249c261b33SJoe Perches __func__); 3251da177e4SLinus Torvalds SetPageError(pg); 3261da177e4SLinus Torvalds ClearPageUptodate(pg); 3271da177e4SLinus Torvalds } 3281da177e4SLinus Torvalds 3299c261b33SJoe Perches jffs2_dbg(1, "%s() returning %d\n", 3309c261b33SJoe Perches __func__, writtenlen > 0 ? writtenlen : ret); 331205c109aSNick Piggin unlock_page(pg); 332205c109aSNick Piggin page_cache_release(pg); 333205c109aSNick Piggin return writtenlen > 0 ? writtenlen : ret; 3341da177e4SLinus Torvalds } 335