1 /* 2 * linux/fs/9p/vfs_addr.c 3 * 4 * This file contians vfs address (mmap) ops for 9P2000. 5 * 6 * Copyright (C) 2005 by Eric Van Hensbergen <ericvh@gmail.com> 7 * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov> 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License version 2 11 * as published by the Free Software Foundation. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to: 20 * Free Software Foundation 21 * 51 Franklin Street, Fifth Floor 22 * Boston, MA 02111-1301 USA 23 * 24 */ 25 26 #include <linux/module.h> 27 #include <linux/errno.h> 28 #include <linux/fs.h> 29 #include <linux/file.h> 30 #include <linux/stat.h> 31 #include <linux/string.h> 32 #include <linux/inet.h> 33 #include <linux/pagemap.h> 34 #include <linux/idr.h> 35 #include <linux/sched.h> 36 #include <net/9p/9p.h> 37 #include <net/9p/client.h> 38 39 #include "v9fs.h" 40 #include "v9fs_vfs.h" 41 42 /** 43 * v9fs_vfs_readpage - read an entire page in from 9P 44 * 45 * @filp: file being read 46 * @page: structure to page 47 * 48 */ 49 50 static int v9fs_vfs_readpage(struct file *filp, struct page *page) 51 { 52 int retval; 53 loff_t offset; 54 char *buffer; 55 56 P9_DPRINTK(P9_DEBUG_VFS, "\n"); 57 buffer = kmap(page); 58 offset = page_offset(page); 59 60 retval = v9fs_file_readn(filp, buffer, NULL, offset, PAGE_CACHE_SIZE); 61 if (retval < 0) 62 goto done; 63 64 memset(buffer + retval, 0, PAGE_CACHE_SIZE - retval); 65 flush_dcache_page(page); 66 SetPageUptodate(page); 67 retval = 0; 68 69 done: 70 kunmap(page); 71 unlock_page(page); 72 return retval; 73 } 74 75 const struct address_space_operations v9fs_addr_operations = { 76 .readpage = v9fs_vfs_readpage, 77 }; 78