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 4202c24a82SJosef Bacik mutex_lock(&inode->i_mutex); 431da177e4SLinus Torvalds /* Trigger GC to flush any pending writes for this inode */ 441da177e4SLinus Torvalds jffs2_flush_wbuf_gc(c, inode->i_ino); 4502c24a82SJosef Bacik mutex_unlock(&inode->i_mutex); 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, 54543ade1fSBadari Pulavarty .read = do_sync_read, 55543ade1fSBadari Pulavarty .aio_read = generic_file_aio_read, 56543ade1fSBadari Pulavarty .write = do_sync_write, 57543ade1fSBadari Pulavarty .aio_write = generic_file_aio_write, 580533400bSStoyan Gaydarov .unlocked_ioctl=jffs2_ioctl, 591da177e4SLinus Torvalds .mmap = generic_file_readonly_mmap, 601da177e4SLinus Torvalds .fsync = jffs2_fsync, 615ffc4ef4SJens Axboe .splice_read = generic_file_splice_read, 621da177e4SLinus Torvalds }; 631da177e4SLinus Torvalds 641da177e4SLinus Torvalds /* jffs2_file_inode_operations */ 651da177e4SLinus Torvalds 6692e1d5beSArjan van de Ven const struct inode_operations jffs2_file_inode_operations = 671da177e4SLinus Torvalds { 684e34e719SChristoph Hellwig .get_acl = jffs2_get_acl, 69f2963d45SChristoph Hellwig .set_acl = jffs2_set_acl, 70aa98d7cfSKaiGai Kohei .setattr = jffs2_setattr, 71aa98d7cfSKaiGai Kohei .setxattr = jffs2_setxattr, 72aa98d7cfSKaiGai Kohei .getxattr = jffs2_getxattr, 73aa98d7cfSKaiGai Kohei .listxattr = jffs2_listxattr, 74aa98d7cfSKaiGai Kohei .removexattr = jffs2_removexattr 751da177e4SLinus Torvalds }; 761da177e4SLinus Torvalds 77f5e54d6eSChristoph Hellwig const struct address_space_operations jffs2_file_address_operations = 781da177e4SLinus Torvalds { 791da177e4SLinus Torvalds .readpage = jffs2_readpage, 80205c109aSNick Piggin .write_begin = jffs2_write_begin, 81205c109aSNick Piggin .write_end = jffs2_write_end, 821da177e4SLinus Torvalds }; 831da177e4SLinus Torvalds 841da177e4SLinus Torvalds static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg) 851da177e4SLinus Torvalds { 861da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 871da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 881da177e4SLinus Torvalds unsigned char *pg_buf; 891da177e4SLinus Torvalds int ret; 901da177e4SLinus Torvalds 919c261b33SJoe Perches jffs2_dbg(2, "%s(): ino #%lu, page at offset 0x%lx\n", 929c261b33SJoe Perches __func__, inode->i_ino, pg->index << PAGE_CACHE_SHIFT); 931da177e4SLinus Torvalds 94cd7619d6SMatt Mackall BUG_ON(!PageLocked(pg)); 951da177e4SLinus Torvalds 961da177e4SLinus Torvalds pg_buf = kmap(pg); 971da177e4SLinus Torvalds /* FIXME: Can kmap fail? */ 981da177e4SLinus Torvalds 991da177e4SLinus Torvalds ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE); 1001da177e4SLinus Torvalds 1011da177e4SLinus Torvalds if (ret) { 1021da177e4SLinus Torvalds ClearPageUptodate(pg); 1031da177e4SLinus Torvalds SetPageError(pg); 1041da177e4SLinus Torvalds } else { 1051da177e4SLinus Torvalds SetPageUptodate(pg); 1061da177e4SLinus Torvalds ClearPageError(pg); 1071da177e4SLinus Torvalds } 1081da177e4SLinus Torvalds 1091da177e4SLinus Torvalds flush_dcache_page(pg); 1101da177e4SLinus Torvalds kunmap(pg); 1111da177e4SLinus Torvalds 1129c261b33SJoe Perches jffs2_dbg(2, "readpage finished\n"); 11357ca7debSAnders Grafström return ret; 1141da177e4SLinus Torvalds } 1151da177e4SLinus Torvalds 1161da177e4SLinus Torvalds int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg) 1171da177e4SLinus Torvalds { 1181da177e4SLinus Torvalds int ret = jffs2_do_readpage_nolock(inode, pg); 1191da177e4SLinus Torvalds unlock_page(pg); 1201da177e4SLinus Torvalds return ret; 1211da177e4SLinus Torvalds } 1221da177e4SLinus Torvalds 1231da177e4SLinus Torvalds 1241da177e4SLinus Torvalds static int jffs2_readpage (struct file *filp, struct page *pg) 1251da177e4SLinus Torvalds { 1261da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host); 1271da177e4SLinus Torvalds int ret; 1281da177e4SLinus Torvalds 129ced22070SDavid Woodhouse mutex_lock(&f->sem); 1301da177e4SLinus Torvalds ret = jffs2_do_readpage_unlock(pg->mapping->host, pg); 131ced22070SDavid Woodhouse mutex_unlock(&f->sem); 1321da177e4SLinus Torvalds return ret; 1331da177e4SLinus Torvalds } 1341da177e4SLinus Torvalds 135205c109aSNick Piggin static int jffs2_write_begin(struct file *filp, struct address_space *mapping, 136205c109aSNick Piggin loff_t pos, unsigned len, unsigned flags, 137205c109aSNick Piggin struct page **pagep, void **fsdata) 1381da177e4SLinus Torvalds { 139205c109aSNick Piggin struct page *pg; 140205c109aSNick Piggin struct inode *inode = mapping->host; 1411da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 1425ffd3412SThomas Betker struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 1435ffd3412SThomas Betker struct jffs2_raw_inode ri; 1445ffd3412SThomas Betker uint32_t alloc_len = 0; 145205c109aSNick Piggin pgoff_t index = pos >> PAGE_CACHE_SHIFT; 146abe2f414SAlexey Korolev uint32_t pageofs = index << PAGE_CACHE_SHIFT; 1471da177e4SLinus Torvalds int ret = 0; 1481da177e4SLinus Torvalds 1499c261b33SJoe Perches jffs2_dbg(1, "%s()\n", __func__); 1501da177e4SLinus Torvalds 1511da177e4SLinus Torvalds if (pageofs > inode->i_size) { 1525ffd3412SThomas Betker ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len, 1535ffd3412SThomas Betker ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE); 1545ffd3412SThomas Betker if (ret) 1555ffd3412SThomas Betker return ret; 1565ffd3412SThomas Betker } 1575ffd3412SThomas Betker 1585ffd3412SThomas Betker mutex_lock(&f->sem); 1595ffd3412SThomas Betker pg = grab_cache_page_write_begin(mapping, index, flags); 1605ffd3412SThomas Betker if (!pg) { 1615ffd3412SThomas Betker if (alloc_len) 1625ffd3412SThomas Betker jffs2_complete_reservation(c); 1635ffd3412SThomas Betker mutex_unlock(&f->sem); 1645ffd3412SThomas Betker return -ENOMEM; 1655ffd3412SThomas Betker } 1665ffd3412SThomas Betker *pagep = pg; 1675ffd3412SThomas Betker 1685ffd3412SThomas Betker if (alloc_len) { 1691da177e4SLinus Torvalds /* Make new hole frag from old EOF to new page */ 1701da177e4SLinus Torvalds struct jffs2_full_dnode *fn; 1711da177e4SLinus Torvalds 1729c261b33SJoe Perches jffs2_dbg(1, "Writing new hole frag 0x%x-0x%x between current EOF and new page\n", 1739c261b33SJoe Perches (unsigned int)inode->i_size, pageofs); 1741da177e4SLinus Torvalds 1751da177e4SLinus Torvalds memset(&ri, 0, sizeof(ri)); 1761da177e4SLinus Torvalds 1771da177e4SLinus Torvalds ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 1781da177e4SLinus Torvalds ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 1791da177e4SLinus Torvalds ri.totlen = cpu_to_je32(sizeof(ri)); 1801da177e4SLinus Torvalds ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 1811da177e4SLinus Torvalds 1821da177e4SLinus Torvalds ri.ino = cpu_to_je32(f->inocache->ino); 1831da177e4SLinus Torvalds ri.version = cpu_to_je32(++f->highest_version); 1841da177e4SLinus Torvalds ri.mode = cpu_to_jemode(inode->i_mode); 1850cfe53d3SEric W. Biederman ri.uid = cpu_to_je16(i_uid_read(inode)); 1860cfe53d3SEric W. Biederman ri.gid = cpu_to_je16(i_gid_read(inode)); 1871da177e4SLinus Torvalds ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs)); 1881da177e4SLinus Torvalds ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds()); 1891da177e4SLinus Torvalds ri.offset = cpu_to_je32(inode->i_size); 1901da177e4SLinus Torvalds ri.dsize = cpu_to_je32(pageofs - inode->i_size); 1911da177e4SLinus Torvalds ri.csize = cpu_to_je32(0); 1921da177e4SLinus Torvalds ri.compr = JFFS2_COMPR_ZERO; 1931da177e4SLinus Torvalds ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 1941da177e4SLinus Torvalds ri.data_crc = cpu_to_je32(0); 1951da177e4SLinus Torvalds 1969fe4854cSDavid Woodhouse fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL); 1971da177e4SLinus Torvalds 1981da177e4SLinus Torvalds if (IS_ERR(fn)) { 1991da177e4SLinus Torvalds ret = PTR_ERR(fn); 2001da177e4SLinus Torvalds jffs2_complete_reservation(c); 201205c109aSNick Piggin goto out_page; 2021da177e4SLinus Torvalds } 2031da177e4SLinus Torvalds ret = jffs2_add_full_dnode_to_inode(c, f, fn); 2041da177e4SLinus Torvalds if (f->metadata) { 2051da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, f->metadata->raw); 2061da177e4SLinus Torvalds jffs2_free_full_dnode(f->metadata); 2071da177e4SLinus Torvalds f->metadata = NULL; 2081da177e4SLinus Torvalds } 2091da177e4SLinus Torvalds if (ret) { 2109c261b33SJoe Perches jffs2_dbg(1, "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n", 2119c261b33SJoe Perches ret); 2121da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, fn->raw); 2131da177e4SLinus Torvalds jffs2_free_full_dnode(fn); 2141da177e4SLinus Torvalds jffs2_complete_reservation(c); 215205c109aSNick Piggin goto out_page; 2161da177e4SLinus Torvalds } 2171da177e4SLinus Torvalds jffs2_complete_reservation(c); 2181da177e4SLinus Torvalds inode->i_size = pageofs; 2191da177e4SLinus Torvalds } 2201da177e4SLinus Torvalds 221205c109aSNick Piggin /* 222205c109aSNick Piggin * Read in the page if it wasn't already present. Cannot optimize away 223205c109aSNick Piggin * the whole page write case until jffs2_write_end can handle the 224205c109aSNick Piggin * case of a short-copy. 225205c109aSNick Piggin */ 226205c109aSNick Piggin if (!PageUptodate(pg)) { 2271da177e4SLinus Torvalds ret = jffs2_do_readpage_nolock(inode, pg); 228205c109aSNick Piggin if (ret) 229205c109aSNick Piggin goto out_page; 2301da177e4SLinus Torvalds } 2315ffd3412SThomas Betker mutex_unlock(&f->sem); 2329c261b33SJoe Perches jffs2_dbg(1, "end write_begin(). pg->flags %lx\n", pg->flags); 233205c109aSNick Piggin return ret; 234205c109aSNick Piggin 235205c109aSNick Piggin out_page: 236205c109aSNick Piggin unlock_page(pg); 237205c109aSNick Piggin page_cache_release(pg); 2385ffd3412SThomas Betker mutex_unlock(&f->sem); 2391da177e4SLinus Torvalds return ret; 2401da177e4SLinus Torvalds } 2411da177e4SLinus Torvalds 242205c109aSNick Piggin static int jffs2_write_end(struct file *filp, struct address_space *mapping, 243205c109aSNick Piggin loff_t pos, unsigned len, unsigned copied, 244205c109aSNick Piggin struct page *pg, void *fsdata) 2451da177e4SLinus Torvalds { 2461da177e4SLinus Torvalds /* Actually commit the write from the page cache page we're looking at. 2471da177e4SLinus Torvalds * For now, we write the full page out each time. It sucks, but it's simple 2481da177e4SLinus Torvalds */ 249205c109aSNick Piggin struct inode *inode = mapping->host; 2501da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 2511da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 2521da177e4SLinus Torvalds struct jffs2_raw_inode *ri; 253205c109aSNick Piggin unsigned start = pos & (PAGE_CACHE_SIZE - 1); 254205c109aSNick Piggin unsigned end = start + copied; 2551da177e4SLinus Torvalds unsigned aligned_start = start & ~3; 2561da177e4SLinus Torvalds int ret = 0; 2571da177e4SLinus Torvalds uint32_t writtenlen = 0; 2581da177e4SLinus Torvalds 2599c261b33SJoe Perches jffs2_dbg(1, "%s(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n", 2609c261b33SJoe Perches __func__, inode->i_ino, pg->index << PAGE_CACHE_SHIFT, 2619c261b33SJoe Perches start, end, pg->flags); 2621da177e4SLinus Torvalds 2631da177e4SLinus Torvalds /* We need to avoid deadlock with page_cache_read() in 264205c109aSNick Piggin jffs2_garbage_collect_pass(). So the page must be 265205c109aSNick Piggin up to date to prevent page_cache_read() from trying 266205c109aSNick Piggin to re-lock it. */ 267205c109aSNick Piggin BUG_ON(!PageUptodate(pg)); 268205c109aSNick Piggin 269205c109aSNick Piggin if (end == PAGE_CACHE_SIZE) { 270cf5eba53SDavid Woodhouse /* When writing out the end of a page, write out the 271cf5eba53SDavid Woodhouse _whole_ page. This helps to reduce the number of 272cf5eba53SDavid Woodhouse nodes in files which have many short writes, like 273cf5eba53SDavid Woodhouse syslog files. */ 2742a754b51SNick Piggin aligned_start = 0; 275cf5eba53SDavid Woodhouse } 2761da177e4SLinus Torvalds 2771da177e4SLinus Torvalds ri = jffs2_alloc_raw_inode(); 2781da177e4SLinus Torvalds 2791da177e4SLinus Torvalds if (!ri) { 2809c261b33SJoe Perches jffs2_dbg(1, "%s(): Allocation of raw inode failed\n", 2819c261b33SJoe Perches __func__); 282205c109aSNick Piggin unlock_page(pg); 283205c109aSNick Piggin page_cache_release(pg); 2841da177e4SLinus Torvalds return -ENOMEM; 2851da177e4SLinus Torvalds } 2861da177e4SLinus Torvalds 2871da177e4SLinus Torvalds /* Set the fields that the generic jffs2_write_inode_range() code can't find */ 2881da177e4SLinus Torvalds ri->ino = cpu_to_je32(inode->i_ino); 2891da177e4SLinus Torvalds ri->mode = cpu_to_jemode(inode->i_mode); 2900cfe53d3SEric W. Biederman ri->uid = cpu_to_je16(i_uid_read(inode)); 2910cfe53d3SEric W. Biederman ri->gid = cpu_to_je16(i_gid_read(inode)); 2921da177e4SLinus Torvalds ri->isize = cpu_to_je32((uint32_t)inode->i_size); 2931da177e4SLinus Torvalds ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds()); 2941da177e4SLinus Torvalds 2951da177e4SLinus Torvalds /* In 2.4, it was already kmapped by generic_file_write(). Doesn't 2961da177e4SLinus Torvalds hurt to do it again. The alternative is ifdefs, which are ugly. */ 2971da177e4SLinus Torvalds kmap(pg); 2981da177e4SLinus Torvalds 2991da177e4SLinus Torvalds ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start, 3001da177e4SLinus Torvalds (pg->index << PAGE_CACHE_SHIFT) + aligned_start, 3011da177e4SLinus Torvalds end - aligned_start, &writtenlen); 3021da177e4SLinus Torvalds 3031da177e4SLinus Torvalds kunmap(pg); 3041da177e4SLinus Torvalds 3051da177e4SLinus Torvalds if (ret) { 3061da177e4SLinus Torvalds /* There was an error writing. */ 3071da177e4SLinus Torvalds SetPageError(pg); 3081da177e4SLinus Torvalds } 3091da177e4SLinus Torvalds 3101da177e4SLinus Torvalds /* Adjust writtenlen for the padding we did, so we don't confuse our caller */ 3112a754b51SNick Piggin writtenlen -= min(writtenlen, (start - aligned_start)); 3121da177e4SLinus Torvalds 3131da177e4SLinus Torvalds if (writtenlen) { 3142a754b51SNick Piggin if (inode->i_size < pos + writtenlen) { 3152a754b51SNick Piggin inode->i_size = pos + writtenlen; 3161da177e4SLinus Torvalds inode->i_blocks = (inode->i_size + 511) >> 9; 3171da177e4SLinus Torvalds 3181da177e4SLinus Torvalds inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime)); 3191da177e4SLinus Torvalds } 3201da177e4SLinus Torvalds } 3211da177e4SLinus Torvalds 3221da177e4SLinus Torvalds jffs2_free_raw_inode(ri); 3231da177e4SLinus Torvalds 3241da177e4SLinus Torvalds if (start+writtenlen < end) { 3251da177e4SLinus Torvalds /* generic_file_write has written more to the page cache than we've 3261da177e4SLinus Torvalds actually written to the medium. Mark the page !Uptodate so that 3271da177e4SLinus Torvalds it gets reread */ 3289c261b33SJoe Perches jffs2_dbg(1, "%s(): Not all bytes written. Marking page !uptodate\n", 3299c261b33SJoe Perches __func__); 3301da177e4SLinus Torvalds SetPageError(pg); 3311da177e4SLinus Torvalds ClearPageUptodate(pg); 3321da177e4SLinus Torvalds } 3331da177e4SLinus Torvalds 3349c261b33SJoe Perches jffs2_dbg(1, "%s() returning %d\n", 3359c261b33SJoe Perches __func__, writtenlen > 0 ? writtenlen : ret); 336205c109aSNick Piggin unlock_page(pg); 337205c109aSNick Piggin page_cache_release(pg); 338205c109aSNick Piggin return writtenlen > 0 ? writtenlen : ret; 3391da177e4SLinus Torvalds } 340