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 383b49c9a1SJeff Layton ret = file_write_and_wait_range(filp, 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 .listxattr = jffs2_listxattr, 701da177e4SLinus Torvalds }; 711da177e4SLinus Torvalds 72f5e54d6eSChristoph Hellwig const struct address_space_operations jffs2_file_address_operations = 731da177e4SLinus Torvalds { 741da177e4SLinus Torvalds .readpage = jffs2_readpage, 75205c109aSNick Piggin .write_begin = jffs2_write_begin, 76205c109aSNick Piggin .write_end = jffs2_write_end, 771da177e4SLinus Torvalds }; 781da177e4SLinus Torvalds 791da177e4SLinus Torvalds static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg) 801da177e4SLinus Torvalds { 811da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 821da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 831da177e4SLinus Torvalds unsigned char *pg_buf; 841da177e4SLinus Torvalds int ret; 851da177e4SLinus Torvalds 869c261b33SJoe Perches jffs2_dbg(2, "%s(): ino #%lu, page at offset 0x%lx\n", 8709cbfeafSKirill A. Shutemov __func__, inode->i_ino, pg->index << PAGE_SHIFT); 881da177e4SLinus Torvalds 89cd7619d6SMatt Mackall BUG_ON(!PageLocked(pg)); 901da177e4SLinus Torvalds 911da177e4SLinus Torvalds pg_buf = kmap(pg); 921da177e4SLinus Torvalds /* FIXME: Can kmap fail? */ 931da177e4SLinus Torvalds 9409cbfeafSKirill A. Shutemov ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_SHIFT, 9509cbfeafSKirill A. Shutemov PAGE_SIZE); 961da177e4SLinus Torvalds 971da177e4SLinus Torvalds if (ret) { 981da177e4SLinus Torvalds ClearPageUptodate(pg); 991da177e4SLinus Torvalds SetPageError(pg); 1001da177e4SLinus Torvalds } else { 1011da177e4SLinus Torvalds SetPageUptodate(pg); 1021da177e4SLinus Torvalds ClearPageError(pg); 1031da177e4SLinus Torvalds } 1041da177e4SLinus Torvalds 1051da177e4SLinus Torvalds flush_dcache_page(pg); 1061da177e4SLinus Torvalds kunmap(pg); 1071da177e4SLinus Torvalds 1089c261b33SJoe Perches jffs2_dbg(2, "readpage finished\n"); 10957ca7debSAnders Grafström return ret; 1101da177e4SLinus Torvalds } 1111da177e4SLinus Torvalds 1121da177e4SLinus Torvalds int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg) 1131da177e4SLinus Torvalds { 1141da177e4SLinus Torvalds int ret = jffs2_do_readpage_nolock(inode, pg); 1151da177e4SLinus Torvalds unlock_page(pg); 1161da177e4SLinus Torvalds return ret; 1171da177e4SLinus Torvalds } 1181da177e4SLinus Torvalds 1191da177e4SLinus Torvalds 1201da177e4SLinus Torvalds static int jffs2_readpage (struct file *filp, struct page *pg) 1211da177e4SLinus Torvalds { 1221da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host); 1231da177e4SLinus Torvalds int ret; 1241da177e4SLinus Torvalds 125ced22070SDavid Woodhouse mutex_lock(&f->sem); 1261da177e4SLinus Torvalds ret = jffs2_do_readpage_unlock(pg->mapping->host, pg); 127ced22070SDavid Woodhouse mutex_unlock(&f->sem); 1281da177e4SLinus Torvalds return ret; 1291da177e4SLinus Torvalds } 1301da177e4SLinus Torvalds 131205c109aSNick Piggin static int jffs2_write_begin(struct file *filp, struct address_space *mapping, 132205c109aSNick Piggin loff_t pos, unsigned len, unsigned flags, 133205c109aSNick Piggin struct page **pagep, void **fsdata) 1341da177e4SLinus Torvalds { 135205c109aSNick Piggin struct page *pg; 136205c109aSNick Piggin struct inode *inode = mapping->host; 1371da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 13809cbfeafSKirill A. Shutemov pgoff_t index = pos >> PAGE_SHIFT; 13909cbfeafSKirill A. Shutemov uint32_t pageofs = index << PAGE_SHIFT; 1401da177e4SLinus Torvalds int ret = 0; 1411da177e4SLinus Torvalds 142157078f6SThomas Betker pg = grab_cache_page_write_begin(mapping, index, flags); 143157078f6SThomas Betker if (!pg) 144157078f6SThomas Betker return -ENOMEM; 145157078f6SThomas Betker *pagep = pg; 146157078f6SThomas Betker 1479c261b33SJoe Perches jffs2_dbg(1, "%s()\n", __func__); 1481da177e4SLinus Torvalds 1491da177e4SLinus Torvalds if (pageofs > inode->i_size) { 1501da177e4SLinus Torvalds /* Make new hole frag from old EOF to new page */ 151157078f6SThomas Betker struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 152157078f6SThomas Betker struct jffs2_raw_inode ri; 1531da177e4SLinus Torvalds struct jffs2_full_dnode *fn; 154157078f6SThomas Betker uint32_t alloc_len; 1551da177e4SLinus Torvalds 1569c261b33SJoe Perches jffs2_dbg(1, "Writing new hole frag 0x%x-0x%x between current EOF and new page\n", 1579c261b33SJoe Perches (unsigned int)inode->i_size, pageofs); 1581da177e4SLinus Torvalds 159157078f6SThomas Betker ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len, 160157078f6SThomas Betker ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE); 161157078f6SThomas Betker if (ret) 162157078f6SThomas Betker goto out_page; 163157078f6SThomas Betker 164157078f6SThomas Betker mutex_lock(&f->sem); 1651da177e4SLinus Torvalds memset(&ri, 0, sizeof(ri)); 1661da177e4SLinus Torvalds 1671da177e4SLinus Torvalds ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 1681da177e4SLinus Torvalds ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 1691da177e4SLinus Torvalds ri.totlen = cpu_to_je32(sizeof(ri)); 1701da177e4SLinus Torvalds ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 1711da177e4SLinus Torvalds 1721da177e4SLinus Torvalds ri.ino = cpu_to_je32(f->inocache->ino); 1731da177e4SLinus Torvalds ri.version = cpu_to_je32(++f->highest_version); 1741da177e4SLinus Torvalds ri.mode = cpu_to_jemode(inode->i_mode); 1750cfe53d3SEric W. Biederman ri.uid = cpu_to_je16(i_uid_read(inode)); 1760cfe53d3SEric W. Biederman ri.gid = cpu_to_je16(i_gid_read(inode)); 1771da177e4SLinus Torvalds ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs)); 1781da177e4SLinus Torvalds ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds()); 1791da177e4SLinus Torvalds ri.offset = cpu_to_je32(inode->i_size); 1801da177e4SLinus Torvalds ri.dsize = cpu_to_je32(pageofs - inode->i_size); 1811da177e4SLinus Torvalds ri.csize = cpu_to_je32(0); 1821da177e4SLinus Torvalds ri.compr = JFFS2_COMPR_ZERO; 1831da177e4SLinus Torvalds ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 1841da177e4SLinus Torvalds ri.data_crc = cpu_to_je32(0); 1851da177e4SLinus Torvalds 1869fe4854cSDavid Woodhouse fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL); 1871da177e4SLinus Torvalds 1881da177e4SLinus Torvalds if (IS_ERR(fn)) { 1891da177e4SLinus Torvalds ret = PTR_ERR(fn); 1901da177e4SLinus Torvalds jffs2_complete_reservation(c); 191157078f6SThomas Betker mutex_unlock(&f->sem); 192205c109aSNick Piggin goto out_page; 1931da177e4SLinus Torvalds } 1941da177e4SLinus Torvalds ret = jffs2_add_full_dnode_to_inode(c, f, fn); 1951da177e4SLinus Torvalds if (f->metadata) { 1961da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, f->metadata->raw); 1971da177e4SLinus Torvalds jffs2_free_full_dnode(f->metadata); 1981da177e4SLinus Torvalds f->metadata = NULL; 1991da177e4SLinus Torvalds } 2001da177e4SLinus Torvalds if (ret) { 2019c261b33SJoe Perches jffs2_dbg(1, "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n", 2029c261b33SJoe Perches ret); 2031da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, fn->raw); 2041da177e4SLinus Torvalds jffs2_free_full_dnode(fn); 2051da177e4SLinus Torvalds jffs2_complete_reservation(c); 206157078f6SThomas Betker mutex_unlock(&f->sem); 207205c109aSNick Piggin goto out_page; 2081da177e4SLinus Torvalds } 2091da177e4SLinus Torvalds jffs2_complete_reservation(c); 2101da177e4SLinus Torvalds inode->i_size = pageofs; 211157078f6SThomas Betker mutex_unlock(&f->sem); 2121da177e4SLinus Torvalds } 2131da177e4SLinus Torvalds 214205c109aSNick Piggin /* 215205c109aSNick Piggin * Read in the page if it wasn't already present. Cannot optimize away 216205c109aSNick Piggin * the whole page write case until jffs2_write_end can handle the 217205c109aSNick Piggin * case of a short-copy. 218205c109aSNick Piggin */ 219205c109aSNick Piggin if (!PageUptodate(pg)) { 220157078f6SThomas Betker mutex_lock(&f->sem); 2211da177e4SLinus Torvalds ret = jffs2_do_readpage_nolock(inode, pg); 222157078f6SThomas Betker mutex_unlock(&f->sem); 223205c109aSNick Piggin if (ret) 224205c109aSNick Piggin goto out_page; 2251da177e4SLinus Torvalds } 2269c261b33SJoe Perches jffs2_dbg(1, "end write_begin(). pg->flags %lx\n", pg->flags); 227205c109aSNick Piggin return ret; 228205c109aSNick Piggin 229205c109aSNick Piggin out_page: 230205c109aSNick Piggin unlock_page(pg); 23109cbfeafSKirill A. Shutemov put_page(pg); 2321da177e4SLinus Torvalds return ret; 2331da177e4SLinus Torvalds } 2341da177e4SLinus Torvalds 235205c109aSNick Piggin static int jffs2_write_end(struct file *filp, struct address_space *mapping, 236205c109aSNick Piggin loff_t pos, unsigned len, unsigned copied, 237205c109aSNick Piggin struct page *pg, void *fsdata) 2381da177e4SLinus Torvalds { 2391da177e4SLinus Torvalds /* Actually commit the write from the page cache page we're looking at. 2401da177e4SLinus Torvalds * For now, we write the full page out each time. It sucks, but it's simple 2411da177e4SLinus Torvalds */ 242205c109aSNick Piggin struct inode *inode = mapping->host; 2431da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 2441da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 2451da177e4SLinus Torvalds struct jffs2_raw_inode *ri; 24609cbfeafSKirill A. Shutemov unsigned start = pos & (PAGE_SIZE - 1); 247205c109aSNick Piggin unsigned end = start + copied; 2481da177e4SLinus Torvalds unsigned aligned_start = start & ~3; 2491da177e4SLinus Torvalds int ret = 0; 2501da177e4SLinus Torvalds uint32_t writtenlen = 0; 2511da177e4SLinus Torvalds 2529c261b33SJoe Perches jffs2_dbg(1, "%s(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n", 25309cbfeafSKirill A. Shutemov __func__, inode->i_ino, pg->index << PAGE_SHIFT, 2549c261b33SJoe Perches start, end, pg->flags); 2551da177e4SLinus Torvalds 2561da177e4SLinus Torvalds /* We need to avoid deadlock with page_cache_read() in 257205c109aSNick Piggin jffs2_garbage_collect_pass(). So the page must be 258205c109aSNick Piggin up to date to prevent page_cache_read() from trying 259205c109aSNick Piggin to re-lock it. */ 260205c109aSNick Piggin BUG_ON(!PageUptodate(pg)); 261205c109aSNick Piggin 26209cbfeafSKirill A. Shutemov if (end == PAGE_SIZE) { 263cf5eba53SDavid Woodhouse /* When writing out the end of a page, write out the 264cf5eba53SDavid Woodhouse _whole_ page. This helps to reduce the number of 265cf5eba53SDavid Woodhouse nodes in files which have many short writes, like 266cf5eba53SDavid Woodhouse syslog files. */ 2672a754b51SNick Piggin aligned_start = 0; 268cf5eba53SDavid Woodhouse } 2691da177e4SLinus Torvalds 2701da177e4SLinus Torvalds ri = jffs2_alloc_raw_inode(); 2711da177e4SLinus Torvalds 2721da177e4SLinus Torvalds if (!ri) { 2739c261b33SJoe Perches jffs2_dbg(1, "%s(): Allocation of raw inode failed\n", 2749c261b33SJoe Perches __func__); 275205c109aSNick Piggin unlock_page(pg); 27609cbfeafSKirill A. Shutemov put_page(pg); 2771da177e4SLinus Torvalds return -ENOMEM; 2781da177e4SLinus Torvalds } 2791da177e4SLinus Torvalds 2801da177e4SLinus Torvalds /* Set the fields that the generic jffs2_write_inode_range() code can't find */ 2811da177e4SLinus Torvalds ri->ino = cpu_to_je32(inode->i_ino); 2821da177e4SLinus Torvalds ri->mode = cpu_to_jemode(inode->i_mode); 2830cfe53d3SEric W. Biederman ri->uid = cpu_to_je16(i_uid_read(inode)); 2840cfe53d3SEric W. Biederman ri->gid = cpu_to_je16(i_gid_read(inode)); 2851da177e4SLinus Torvalds ri->isize = cpu_to_je32((uint32_t)inode->i_size); 2861da177e4SLinus Torvalds ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds()); 2871da177e4SLinus Torvalds 2881da177e4SLinus Torvalds /* In 2.4, it was already kmapped by generic_file_write(). Doesn't 2891da177e4SLinus Torvalds hurt to do it again. The alternative is ifdefs, which are ugly. */ 2901da177e4SLinus Torvalds kmap(pg); 2911da177e4SLinus Torvalds 2921da177e4SLinus Torvalds ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start, 29309cbfeafSKirill A. Shutemov (pg->index << PAGE_SHIFT) + aligned_start, 2941da177e4SLinus Torvalds end - aligned_start, &writtenlen); 2951da177e4SLinus Torvalds 2961da177e4SLinus Torvalds kunmap(pg); 2971da177e4SLinus Torvalds 2981da177e4SLinus Torvalds if (ret) { 2991da177e4SLinus Torvalds /* There was an error writing. */ 3001da177e4SLinus Torvalds SetPageError(pg); 3011da177e4SLinus Torvalds } 3021da177e4SLinus Torvalds 3031da177e4SLinus Torvalds /* Adjust writtenlen for the padding we did, so we don't confuse our caller */ 3042a754b51SNick Piggin writtenlen -= min(writtenlen, (start - aligned_start)); 3051da177e4SLinus Torvalds 3061da177e4SLinus Torvalds if (writtenlen) { 3072a754b51SNick Piggin if (inode->i_size < pos + writtenlen) { 3082a754b51SNick Piggin inode->i_size = pos + writtenlen; 3091da177e4SLinus Torvalds inode->i_blocks = (inode->i_size + 511) >> 9; 3101da177e4SLinus Torvalds 3111da177e4SLinus Torvalds inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime)); 3121da177e4SLinus Torvalds } 3131da177e4SLinus Torvalds } 3141da177e4SLinus Torvalds 3151da177e4SLinus Torvalds jffs2_free_raw_inode(ri); 3161da177e4SLinus Torvalds 3171da177e4SLinus Torvalds if (start+writtenlen < end) { 3181da177e4SLinus Torvalds /* generic_file_write has written more to the page cache than we've 3191da177e4SLinus Torvalds actually written to the medium. Mark the page !Uptodate so that 3201da177e4SLinus Torvalds it gets reread */ 3219c261b33SJoe Perches jffs2_dbg(1, "%s(): Not all bytes written. Marking page !uptodate\n", 3229c261b33SJoe Perches __func__); 3231da177e4SLinus Torvalds SetPageError(pg); 3241da177e4SLinus Torvalds ClearPageUptodate(pg); 3251da177e4SLinus Torvalds } 3261da177e4SLinus Torvalds 3279c261b33SJoe Perches jffs2_dbg(1, "%s() returning %d\n", 3289c261b33SJoe Perches __func__, writtenlen > 0 ? writtenlen : ret); 329205c109aSNick Piggin unlock_page(pg); 33009cbfeafSKirill A. Shutemov put_page(pg); 331205c109aSNick Piggin return writtenlen > 0 ? writtenlen : ret; 3321da177e4SLinus Torvalds } 333