git://bbs.cooldavid.org / net-next-2.6.git / blame
| Commit | Line | Data |
|---|---|---|
| b3b94faa DT |
1 | /* |
| 2 | * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. | |
| 3 | * Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved. | |
| 4 | * | |
| 5 | * This copyrighted material is made available to anyone wishing to use, | |
| 6 | * modify, copy, or redistribute it subject to the terms and conditions | |
| 7 | * of the GNU General Public License v.2. | |
| 8 | */ | |
| 9 | ||
| 10 | #include <linux/sched.h> | |
| 11 | #include <linux/slab.h> | |
| 12 | #include <linux/spinlock.h> | |
| 13 | #include <linux/completion.h> | |
| 14 | #include <linux/buffer_head.h> | |
| 15 | #include <linux/smp_lock.h> | |
| 16 | #include <asm/semaphore.h> | |
| 17 | ||
| 18 | #include "gfs2.h" | |
| 19 | #include "dir.h" | |
| 20 | #include "glock.h" | |
| 21 | #include "ops_dentry.h" | |
| 22 | ||
| 23 | /** | |
| 24 | * gfs2_drevalidate - Check directory lookup consistency | |
| 25 | * @dentry: the mapping to check | |
| 26 | * @nd: | |
| 27 | * | |
| 28 | * Check to make sure the lookup necessary to arrive at this inode from its | |
| 29 | * parent is still good. | |
| 30 | * | |
| 31 | * Returns: 1 if the dentry is ok, 0 if it isn't | |
| 32 | */ | |
| 33 | ||
| 34 | static int gfs2_drevalidate(struct dentry *dentry, struct nameidata *nd) | |
| 35 | { | |
| 36 | struct dentry *parent = dget_parent(dentry); | |
| 37 | struct gfs2_inode *dip = get_v2ip(parent->d_inode); | |
| 38 | struct gfs2_sbd *sdp = dip->i_sbd; | |
| 39 | struct inode *inode; | |
| 40 | struct gfs2_holder d_gh; | |
| 41 | struct gfs2_inode *ip; | |
| 42 | struct gfs2_inum inum; | |
| 43 | unsigned int type; | |
| 44 | int error; | |
| 45 | ||
| 46 | lock_kernel(); | |
| 47 | ||
| 48 | atomic_inc(&sdp->sd_ops_dentry); | |
| 49 | ||
| 50 | inode = dentry->d_inode; | |
| 51 | if (inode && is_bad_inode(inode)) | |
| 52 | goto invalid; | |
| 53 | ||
| 54 | error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh); | |
| 55 | if (error) | |
| 56 | goto fail; | |
| 57 | ||
| 58 | error = gfs2_dir_search(dip, &dentry->d_name, &inum, &type); | |
| 59 | switch (error) { | |
| 60 | case 0: | |
| 61 | if (!inode) | |
| 62 | goto invalid_gunlock; | |
| 63 | break; | |
| 64 | case -ENOENT: | |
| 65 | if (!inode) | |
| 66 | goto valid_gunlock; | |
| 67 | goto invalid_gunlock; | |
| 68 | default: | |
| 69 | goto fail_gunlock; | |
| 70 | } | |
| 71 | ||
| 72 | ip = get_v2ip(inode); | |
| 73 | ||
| 74 | if (!gfs2_inum_equal(&ip->i_num, &inum)) | |
| 75 | goto invalid_gunlock; | |
| 76 | ||
| 77 | if (IF2DT(ip->i_di.di_mode) != type) { | |
| 78 | gfs2_consist_inode(dip); | |
| 79 | goto fail_gunlock; | |
| 80 | } | |
| 81 | ||
| 82 | valid_gunlock: | |
| 83 | gfs2_glock_dq_uninit(&d_gh); | |
| 84 | ||
| 85 | valid: | |
| 86 | unlock_kernel(); | |
| 87 | dput(parent); | |
| 88 | return 1; | |
| 89 | ||
| 90 | invalid_gunlock: | |
| 91 | gfs2_glock_dq_uninit(&d_gh); | |
| 92 | ||
| 93 | invalid: | |
| 94 | if (inode && S_ISDIR(inode->i_mode)) { | |
| 95 | if (have_submounts(dentry)) | |
| 96 | goto valid; | |
| 97 | shrink_dcache_parent(dentry); | |
| 98 | } | |
| 99 | d_drop(dentry); | |
| 100 | ||
| 101 | unlock_kernel(); | |
| 102 | dput(parent); | |
| 103 | return 0; | |
| 104 | ||
| 105 | fail_gunlock: | |
| 106 | gfs2_glock_dq_uninit(&d_gh); | |
| 107 | ||
| 108 | fail: | |
| 109 | unlock_kernel(); | |
| 110 | dput(parent); | |
| 111 | return 0; | |
| 112 | } | |
| 113 | ||
| 114 | struct dentry_operations gfs2_dops = { | |
| 115 | .d_revalidate = gfs2_drevalidate, | |
| 116 | }; | |
| 117 |