Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | #include <linux/namei.h> |
| 36 | |
| 37 | #include "vxfs.h" |
| 38 | #include "vxfs_inode.h" |
| 39 | |
| 40 | |
Al Viro | 008b150 | 2005-08-20 00:17:39 +0100 | [diff] [blame] | 41 | static void * vxfs_immed_follow_link(struct dentry *, struct nameidata *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 42 | |
| 43 | static int vxfs_immed_readpage(struct file *, struct page *); |
| 44 | |
| 45 | /* |
| 46 | * Inode operations for immed symlinks. |
| 47 | * |
| 48 | * Unliked all other operations we do not go through the pagecache, |
| 49 | * but do all work directly on the inode. |
| 50 | */ |
Arjan van de Ven | 754661f | 2007-02-12 00:55:38 -0800 | [diff] [blame] | 51 | const struct inode_operations vxfs_immed_symlink_iops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 52 | .readlink = generic_readlink, |
| 53 | .follow_link = vxfs_immed_follow_link, |
| 54 | }; |
| 55 | |
| 56 | /* |
| 57 | * Adress space operations for immed files and directories. |
| 58 | */ |
Christoph Hellwig | f5e54d6 | 2006-06-28 04:26:44 -0700 | [diff] [blame] | 59 | const struct address_space_operations vxfs_immed_aops = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | .readpage = vxfs_immed_readpage, |
| 61 | }; |
| 62 | |
| 63 | /** |
| 64 | * vxfs_immed_follow_link - follow immed symlink |
| 65 | * @dp: dentry for the link |
| 66 | * @np: pathname lookup data for the current path walk |
| 67 | * |
| 68 | * Description: |
| 69 | * vxfs_immed_follow_link restarts the pathname lookup with |
| 70 | * the data obtained from @dp. |
| 71 | * |
| 72 | * Returns: |
| 73 | * Zero on success, else a negative error code. |
| 74 | */ |
Alexey Dobriyan | a5ea169 | 2005-08-21 01:08:36 +0400 | [diff] [blame] | 75 | static void * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | vxfs_immed_follow_link(struct dentry *dp, struct nameidata *np) |
| 77 | { |
| 78 | struct vxfs_inode_info *vip = VXFS_INO(dp->d_inode); |
| 79 | nd_set_link(np, vip->vii_immed.vi_immed); |
Al Viro | 008b150 | 2005-08-20 00:17:39 +0100 | [diff] [blame] | 80 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | } |
| 82 | |
| 83 | /** |
| 84 | * vxfs_immed_readpage - read part of an immed inode into pagecache |
| 85 | * @file: file context (unused) |
| 86 | * @page: page frame to fill in. |
| 87 | * |
| 88 | * Description: |
| 89 | * vxfs_immed_readpage reads a part of the immed area of the |
| 90 | * file that hosts @pp into the pagecache. |
| 91 | * |
| 92 | * Returns: |
| 93 | * Zero on success, else a negative error code. |
| 94 | * |
| 95 | * Locking status: |
| 96 | * @page is locked and will be unlocked. |
| 97 | */ |
| 98 | static int |
| 99 | vxfs_immed_readpage(struct file *fp, struct page *pp) |
| 100 | { |
| 101 | struct vxfs_inode_info *vip = VXFS_INO(pp->mapping->host); |
Andrew Morton | 54b21a7 | 2006-01-08 01:03:05 -0800 | [diff] [blame] | 102 | u_int64_t offset = (u_int64_t)pp->index << PAGE_CACHE_SHIFT; |
| 103 | caddr_t kaddr; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | |
| 105 | kaddr = kmap(pp); |
| 106 | memcpy(kaddr, vip->vii_immed.vi_immed + offset, PAGE_CACHE_SIZE); |
| 107 | kunmap(pp); |
| 108 | |
| 109 | flush_dcache_page(pp); |
| 110 | SetPageUptodate(pp); |
| 111 | unlock_page(pp); |
| 112 | |
| 113 | return 0; |
| 114 | } |