1 /* 2 * Copyright (c) 2000-2001 Christoph Hellwig. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions, and the following disclaimer, 10 * without modification. 11 * 2. The name of the author may not be used to endorse or promote products 12 * derived from this software without specific prior written permission. 13 * 14 * Alternatively, this software may be distributed under the terms of the 15 * GNU General Public License ("GPL"). 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR 21 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 /* 31 * Veritas filesystem driver - support for 'immed' inodes. 32 */ 33 #include <linux/fs.h> 34 #include <linux/pagemap.h> 35 36 #include "vxfs.h" 37 #include "vxfs_extern.h" 38 #include "vxfs_inode.h" 39 40 41 static int vxfs_immed_readpage(struct file *, struct page *); 42 43 /* 44 * Address space operations for immed files and directories. 45 */ 46 const struct address_space_operations vxfs_immed_aops = { 47 .readpage = vxfs_immed_readpage, 48 }; 49 50 /** 51 * vxfs_immed_readpage - read part of an immed inode into pagecache 52 * @file: file context (unused) 53 * @page: page frame to fill in. 54 * 55 * Description: 56 * vxfs_immed_readpage reads a part of the immed area of the 57 * file that hosts @pp into the pagecache. 58 * 59 * Returns: 60 * Zero on success, else a negative error code. 61 * 62 * Locking status: 63 * @page is locked and will be unlocked. 64 */ 65 static int 66 vxfs_immed_readpage(struct file *fp, struct page *pp) 67 { 68 struct vxfs_inode_info *vip = VXFS_INO(pp->mapping->host); 69 u_int64_t offset = (u_int64_t)pp->index << PAGE_CACHE_SHIFT; 70 caddr_t kaddr; 71 72 kaddr = kmap(pp); 73 memcpy(kaddr, vip->vii_immed.vi_immed + offset, PAGE_CACHE_SIZE); 74 kunmap(pp); 75 76 flush_dcache_page(pp); 77 SetPageUptodate(pp); 78 unlock_page(pp); 79 80 return 0; 81 } 82