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, 69aa98d7cfSKaiGai Kohei .setattr = jffs2_setattr, 70aa98d7cfSKaiGai Kohei .setxattr = jffs2_setxattr, 71aa98d7cfSKaiGai Kohei .getxattr = jffs2_getxattr, 72aa98d7cfSKaiGai Kohei .listxattr = jffs2_listxattr, 73aa98d7cfSKaiGai Kohei .removexattr = jffs2_removexattr 741da177e4SLinus Torvalds }; 751da177e4SLinus Torvalds 76f5e54d6eSChristoph Hellwig const struct address_space_operations jffs2_file_address_operations = 771da177e4SLinus Torvalds { 781da177e4SLinus Torvalds .readpage = jffs2_readpage, 79205c109aSNick Piggin .write_begin = jffs2_write_begin, 80205c109aSNick Piggin .write_end = jffs2_write_end, 811da177e4SLinus Torvalds }; 821da177e4SLinus Torvalds 831da177e4SLinus Torvalds static int jffs2_do_readpage_nolock (struct inode *inode, struct page *pg) 841da177e4SLinus Torvalds { 851da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 861da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 871da177e4SLinus Torvalds unsigned char *pg_buf; 881da177e4SLinus Torvalds int ret; 891da177e4SLinus Torvalds 909c261b33SJoe Perches jffs2_dbg(2, "%s(): ino #%lu, page at offset 0x%lx\n", 919c261b33SJoe Perches __func__, inode->i_ino, pg->index << PAGE_CACHE_SHIFT); 921da177e4SLinus Torvalds 93cd7619d6SMatt Mackall BUG_ON(!PageLocked(pg)); 941da177e4SLinus Torvalds 951da177e4SLinus Torvalds pg_buf = kmap(pg); 961da177e4SLinus Torvalds /* FIXME: Can kmap fail? */ 971da177e4SLinus Torvalds 981da177e4SLinus Torvalds ret = jffs2_read_inode_range(c, f, pg_buf, pg->index << PAGE_CACHE_SHIFT, PAGE_CACHE_SIZE); 991da177e4SLinus Torvalds 1001da177e4SLinus Torvalds if (ret) { 1011da177e4SLinus Torvalds ClearPageUptodate(pg); 1021da177e4SLinus Torvalds SetPageError(pg); 1031da177e4SLinus Torvalds } else { 1041da177e4SLinus Torvalds SetPageUptodate(pg); 1051da177e4SLinus Torvalds ClearPageError(pg); 1061da177e4SLinus Torvalds } 1071da177e4SLinus Torvalds 1081da177e4SLinus Torvalds flush_dcache_page(pg); 1091da177e4SLinus Torvalds kunmap(pg); 1101da177e4SLinus Torvalds 1119c261b33SJoe Perches jffs2_dbg(2, "readpage finished\n"); 11257ca7debSAnders Grafström return ret; 1131da177e4SLinus Torvalds } 1141da177e4SLinus Torvalds 1151da177e4SLinus Torvalds int jffs2_do_readpage_unlock(struct inode *inode, struct page *pg) 1161da177e4SLinus Torvalds { 1171da177e4SLinus Torvalds int ret = jffs2_do_readpage_nolock(inode, pg); 1181da177e4SLinus Torvalds unlock_page(pg); 1191da177e4SLinus Torvalds return ret; 1201da177e4SLinus Torvalds } 1211da177e4SLinus Torvalds 1221da177e4SLinus Torvalds 1231da177e4SLinus Torvalds static int jffs2_readpage (struct file *filp, struct page *pg) 1241da177e4SLinus Torvalds { 1251da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(pg->mapping->host); 1261da177e4SLinus Torvalds int ret; 1271da177e4SLinus Torvalds 128ced22070SDavid Woodhouse mutex_lock(&f->sem); 1291da177e4SLinus Torvalds ret = jffs2_do_readpage_unlock(pg->mapping->host, pg); 130ced22070SDavid Woodhouse mutex_unlock(&f->sem); 1311da177e4SLinus Torvalds return ret; 1321da177e4SLinus Torvalds } 1331da177e4SLinus Torvalds 134205c109aSNick Piggin static int jffs2_write_begin(struct file *filp, struct address_space *mapping, 135205c109aSNick Piggin loff_t pos, unsigned len, unsigned flags, 136205c109aSNick Piggin struct page **pagep, void **fsdata) 1371da177e4SLinus Torvalds { 138205c109aSNick Piggin struct page *pg; 139205c109aSNick Piggin struct inode *inode = mapping->host; 1401da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 141205c109aSNick Piggin pgoff_t index = pos >> PAGE_CACHE_SHIFT; 142abe2f414SAlexey Korolev uint32_t pageofs = index << PAGE_CACHE_SHIFT; 1431da177e4SLinus Torvalds int ret = 0; 1441da177e4SLinus Torvalds 14554566b2cSNick Piggin pg = grab_cache_page_write_begin(mapping, index, flags); 146205c109aSNick Piggin if (!pg) 147205c109aSNick Piggin return -ENOMEM; 148205c109aSNick Piggin *pagep = pg; 149205c109aSNick Piggin 1509c261b33SJoe Perches jffs2_dbg(1, "%s()\n", __func__); 1511da177e4SLinus Torvalds 1521da177e4SLinus Torvalds if (pageofs > inode->i_size) { 1531da177e4SLinus Torvalds /* Make new hole frag from old EOF to new page */ 1541da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 1551da177e4SLinus Torvalds struct jffs2_raw_inode ri; 1561da177e4SLinus Torvalds struct jffs2_full_dnode *fn; 1579fe4854cSDavid Woodhouse uint32_t alloc_len; 1581da177e4SLinus Torvalds 1599c261b33SJoe Perches jffs2_dbg(1, "Writing new hole frag 0x%x-0x%x between current EOF and new page\n", 1609c261b33SJoe Perches (unsigned int)inode->i_size, pageofs); 1611da177e4SLinus Torvalds 1629fe4854cSDavid Woodhouse ret = jffs2_reserve_space(c, sizeof(ri), &alloc_len, 163e631ddbaSFerenc Havasi ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE); 1641da177e4SLinus Torvalds if (ret) 165205c109aSNick Piggin goto out_page; 1661da177e4SLinus Torvalds 167ced22070SDavid Woodhouse mutex_lock(&f->sem); 1681da177e4SLinus Torvalds memset(&ri, 0, sizeof(ri)); 1691da177e4SLinus Torvalds 1701da177e4SLinus Torvalds ri.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK); 1711da177e4SLinus Torvalds ri.nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE); 1721da177e4SLinus Torvalds ri.totlen = cpu_to_je32(sizeof(ri)); 1731da177e4SLinus Torvalds ri.hdr_crc = cpu_to_je32(crc32(0, &ri, sizeof(struct jffs2_unknown_node)-4)); 1741da177e4SLinus Torvalds 1751da177e4SLinus Torvalds ri.ino = cpu_to_je32(f->inocache->ino); 1761da177e4SLinus Torvalds ri.version = cpu_to_je32(++f->highest_version); 1771da177e4SLinus Torvalds ri.mode = cpu_to_jemode(inode->i_mode); 1781da177e4SLinus Torvalds ri.uid = cpu_to_je16(inode->i_uid); 1791da177e4SLinus Torvalds ri.gid = cpu_to_je16(inode->i_gid); 1801da177e4SLinus Torvalds ri.isize = cpu_to_je32(max((uint32_t)inode->i_size, pageofs)); 1811da177e4SLinus Torvalds ri.atime = ri.ctime = ri.mtime = cpu_to_je32(get_seconds()); 1821da177e4SLinus Torvalds ri.offset = cpu_to_je32(inode->i_size); 1831da177e4SLinus Torvalds ri.dsize = cpu_to_je32(pageofs - inode->i_size); 1841da177e4SLinus Torvalds ri.csize = cpu_to_je32(0); 1851da177e4SLinus Torvalds ri.compr = JFFS2_COMPR_ZERO; 1861da177e4SLinus Torvalds ri.node_crc = cpu_to_je32(crc32(0, &ri, sizeof(ri)-8)); 1871da177e4SLinus Torvalds ri.data_crc = cpu_to_je32(0); 1881da177e4SLinus Torvalds 1899fe4854cSDavid Woodhouse fn = jffs2_write_dnode(c, f, &ri, NULL, 0, ALLOC_NORMAL); 1901da177e4SLinus Torvalds 1911da177e4SLinus Torvalds if (IS_ERR(fn)) { 1921da177e4SLinus Torvalds ret = PTR_ERR(fn); 1931da177e4SLinus Torvalds jffs2_complete_reservation(c); 194ced22070SDavid Woodhouse mutex_unlock(&f->sem); 195205c109aSNick Piggin goto out_page; 1961da177e4SLinus Torvalds } 1971da177e4SLinus Torvalds ret = jffs2_add_full_dnode_to_inode(c, f, fn); 1981da177e4SLinus Torvalds if (f->metadata) { 1991da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, f->metadata->raw); 2001da177e4SLinus Torvalds jffs2_free_full_dnode(f->metadata); 2011da177e4SLinus Torvalds f->metadata = NULL; 2021da177e4SLinus Torvalds } 2031da177e4SLinus Torvalds if (ret) { 2049c261b33SJoe Perches jffs2_dbg(1, "Eep. add_full_dnode_to_inode() failed in write_begin, returned %d\n", 2059c261b33SJoe Perches ret); 2061da177e4SLinus Torvalds jffs2_mark_node_obsolete(c, fn->raw); 2071da177e4SLinus Torvalds jffs2_free_full_dnode(fn); 2081da177e4SLinus Torvalds jffs2_complete_reservation(c); 209ced22070SDavid Woodhouse mutex_unlock(&f->sem); 210205c109aSNick Piggin goto out_page; 2111da177e4SLinus Torvalds } 2121da177e4SLinus Torvalds jffs2_complete_reservation(c); 2131da177e4SLinus Torvalds inode->i_size = pageofs; 214ced22070SDavid Woodhouse mutex_unlock(&f->sem); 2151da177e4SLinus Torvalds } 2161da177e4SLinus Torvalds 217205c109aSNick Piggin /* 218205c109aSNick Piggin * Read in the page if it wasn't already present. Cannot optimize away 219205c109aSNick Piggin * the whole page write case until jffs2_write_end can handle the 220205c109aSNick Piggin * case of a short-copy. 221205c109aSNick Piggin */ 222205c109aSNick Piggin if (!PageUptodate(pg)) { 223ced22070SDavid Woodhouse mutex_lock(&f->sem); 2241da177e4SLinus Torvalds ret = jffs2_do_readpage_nolock(inode, pg); 225ced22070SDavid Woodhouse mutex_unlock(&f->sem); 226205c109aSNick Piggin if (ret) 227205c109aSNick Piggin goto out_page; 2281da177e4SLinus Torvalds } 2299c261b33SJoe Perches jffs2_dbg(1, "end write_begin(). pg->flags %lx\n", pg->flags); 230205c109aSNick Piggin return ret; 231205c109aSNick Piggin 232205c109aSNick Piggin out_page: 233205c109aSNick Piggin unlock_page(pg); 234205c109aSNick Piggin page_cache_release(pg); 2351da177e4SLinus Torvalds return ret; 2361da177e4SLinus Torvalds } 2371da177e4SLinus Torvalds 238205c109aSNick Piggin static int jffs2_write_end(struct file *filp, struct address_space *mapping, 239205c109aSNick Piggin loff_t pos, unsigned len, unsigned copied, 240205c109aSNick Piggin struct page *pg, void *fsdata) 2411da177e4SLinus Torvalds { 2421da177e4SLinus Torvalds /* Actually commit the write from the page cache page we're looking at. 2431da177e4SLinus Torvalds * For now, we write the full page out each time. It sucks, but it's simple 2441da177e4SLinus Torvalds */ 245205c109aSNick Piggin struct inode *inode = mapping->host; 2461da177e4SLinus Torvalds struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode); 2471da177e4SLinus Torvalds struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb); 2481da177e4SLinus Torvalds struct jffs2_raw_inode *ri; 249205c109aSNick Piggin unsigned start = pos & (PAGE_CACHE_SIZE - 1); 250205c109aSNick Piggin unsigned end = start + copied; 2511da177e4SLinus Torvalds unsigned aligned_start = start & ~3; 2521da177e4SLinus Torvalds int ret = 0; 2531da177e4SLinus Torvalds uint32_t writtenlen = 0; 2541da177e4SLinus Torvalds 2559c261b33SJoe Perches jffs2_dbg(1, "%s(): ino #%lu, page at 0x%lx, range %d-%d, flags %lx\n", 2569c261b33SJoe Perches __func__, inode->i_ino, pg->index << PAGE_CACHE_SHIFT, 2579c261b33SJoe Perches start, end, pg->flags); 2581da177e4SLinus Torvalds 2591da177e4SLinus Torvalds /* We need to avoid deadlock with page_cache_read() in 260205c109aSNick Piggin jffs2_garbage_collect_pass(). So the page must be 261205c109aSNick Piggin up to date to prevent page_cache_read() from trying 262205c109aSNick Piggin to re-lock it. */ 263205c109aSNick Piggin BUG_ON(!PageUptodate(pg)); 264205c109aSNick Piggin 265205c109aSNick Piggin if (end == PAGE_CACHE_SIZE) { 266cf5eba53SDavid Woodhouse /* When writing out the end of a page, write out the 267cf5eba53SDavid Woodhouse _whole_ page. This helps to reduce the number of 268cf5eba53SDavid Woodhouse nodes in files which have many short writes, like 269cf5eba53SDavid Woodhouse syslog files. */ 2702a754b51SNick Piggin aligned_start = 0; 271cf5eba53SDavid Woodhouse } 2721da177e4SLinus Torvalds 2731da177e4SLinus Torvalds ri = jffs2_alloc_raw_inode(); 2741da177e4SLinus Torvalds 2751da177e4SLinus Torvalds if (!ri) { 2769c261b33SJoe Perches jffs2_dbg(1, "%s(): Allocation of raw inode failed\n", 2779c261b33SJoe Perches __func__); 278205c109aSNick Piggin unlock_page(pg); 279205c109aSNick Piggin page_cache_release(pg); 2801da177e4SLinus Torvalds return -ENOMEM; 2811da177e4SLinus Torvalds } 2821da177e4SLinus Torvalds 2831da177e4SLinus Torvalds /* Set the fields that the generic jffs2_write_inode_range() code can't find */ 2841da177e4SLinus Torvalds ri->ino = cpu_to_je32(inode->i_ino); 2851da177e4SLinus Torvalds ri->mode = cpu_to_jemode(inode->i_mode); 2861da177e4SLinus Torvalds ri->uid = cpu_to_je16(inode->i_uid); 2871da177e4SLinus Torvalds ri->gid = cpu_to_je16(inode->i_gid); 2881da177e4SLinus Torvalds ri->isize = cpu_to_je32((uint32_t)inode->i_size); 2891da177e4SLinus Torvalds ri->atime = ri->ctime = ri->mtime = cpu_to_je32(get_seconds()); 2901da177e4SLinus Torvalds 2911da177e4SLinus Torvalds /* In 2.4, it was already kmapped by generic_file_write(). Doesn't 2921da177e4SLinus Torvalds hurt to do it again. The alternative is ifdefs, which are ugly. */ 2931da177e4SLinus Torvalds kmap(pg); 2941da177e4SLinus Torvalds 2951da177e4SLinus Torvalds ret = jffs2_write_inode_range(c, f, ri, page_address(pg) + aligned_start, 2961da177e4SLinus Torvalds (pg->index << PAGE_CACHE_SHIFT) + aligned_start, 2971da177e4SLinus Torvalds end - aligned_start, &writtenlen); 2981da177e4SLinus Torvalds 2991da177e4SLinus Torvalds kunmap(pg); 3001da177e4SLinus Torvalds 3011da177e4SLinus Torvalds if (ret) { 3021da177e4SLinus Torvalds /* There was an error writing. */ 3031da177e4SLinus Torvalds SetPageError(pg); 3041da177e4SLinus Torvalds } 3051da177e4SLinus Torvalds 3061da177e4SLinus Torvalds /* Adjust writtenlen for the padding we did, so we don't confuse our caller */ 3072a754b51SNick Piggin writtenlen -= min(writtenlen, (start - aligned_start)); 3081da177e4SLinus Torvalds 3091da177e4SLinus Torvalds if (writtenlen) { 3102a754b51SNick Piggin if (inode->i_size < pos + writtenlen) { 3112a754b51SNick Piggin inode->i_size = pos + writtenlen; 3121da177e4SLinus Torvalds inode->i_blocks = (inode->i_size + 511) >> 9; 3131da177e4SLinus Torvalds 3141da177e4SLinus Torvalds inode->i_ctime = inode->i_mtime = ITIME(je32_to_cpu(ri->ctime)); 3151da177e4SLinus Torvalds } 3161da177e4SLinus Torvalds } 3171da177e4SLinus Torvalds 3181da177e4SLinus Torvalds jffs2_free_raw_inode(ri); 3191da177e4SLinus Torvalds 3201da177e4SLinus Torvalds if (start+writtenlen < end) { 3211da177e4SLinus Torvalds /* generic_file_write has written more to the page cache than we've 3221da177e4SLinus Torvalds actually written to the medium. Mark the page !Uptodate so that 3231da177e4SLinus Torvalds it gets reread */ 3249c261b33SJoe Perches jffs2_dbg(1, "%s(): Not all bytes written. Marking page !uptodate\n", 3259c261b33SJoe Perches __func__); 3261da177e4SLinus Torvalds SetPageError(pg); 3271da177e4SLinus Torvalds ClearPageUptodate(pg); 3281da177e4SLinus Torvalds } 3291da177e4SLinus Torvalds 3309c261b33SJoe Perches jffs2_dbg(1, "%s() returning %d\n", 3319c261b33SJoe Perches __func__, writtenlen > 0 ? writtenlen : ret); 332205c109aSNick Piggin unlock_page(pg); 333205c109aSNick Piggin page_cache_release(pg); 334205c109aSNick Piggin return writtenlen > 0 ? writtenlen : ret; 3351da177e4SLinus Torvalds } 336