orangefs: Util functions shouldn't operate on inode where it can be avoided.
[linux-2.6-block.git] / fs / orangefs / dcache.c
CommitLineData
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1/*
2 * (C) 2001 Clemson University and The University of Chicago
3 *
4 * See COPYING in top-level directory.
5 */
6
7/*
8 * Implementation of dentry (directory cache) functions.
9 */
10
11#include "protocol.h"
575e9461 12#include "orangefs-kernel.h"
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13
14/* Returns 1 if dentry can still be trusted, else 0. */
8bb8aefd 15static int orangefs_revalidate_lookup(struct dentry *dentry)
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16{
17 struct dentry *parent_dentry = dget_parent(dentry);
18 struct inode *parent_inode = parent_dentry->d_inode;
8bb8aefd 19 struct orangefs_inode_s *parent = ORANGEFS_I(parent_inode);
5db11c21 20 struct inode *inode = dentry->d_inode;
8bb8aefd 21 struct orangefs_kernel_op_s *new_op;
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22 int ret = 0;
23 int err = 0;
24
25 gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: attempting lookup.\n", __func__);
26
8bb8aefd 27 new_op = op_alloc(ORANGEFS_VFS_OP_LOOKUP);
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28 if (!new_op)
29 goto out_put_parent;
30
8bb8aefd 31 new_op->upcall.req.lookup.sym_follow = ORANGEFS_LOOKUP_LINK_NO_FOLLOW;
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32 new_op->upcall.req.lookup.parent_refn = parent->refn;
33 strncpy(new_op->upcall.req.lookup.d_name,
34 dentry->d_name.name,
8bb8aefd 35 ORANGEFS_NAME_LEN);
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36
37 gossip_debug(GOSSIP_DCACHE_DEBUG,
38 "%s:%s:%d interrupt flag [%d]\n",
39 __FILE__,
40 __func__,
41 __LINE__,
42 get_interruptible_flag(parent_inode));
43
8bb8aefd 44 err = service_operation(new_op, "orangefs_lookup",
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45 get_interruptible_flag(parent_inode));
46 if (err)
47 goto out_drop;
48
49 if (new_op->downcall.status != 0 ||
50 !match_handle(new_op->downcall.resp.lookup.refn.khandle, inode)) {
51 gossip_debug(GOSSIP_DCACHE_DEBUG,
52 "%s:%s:%d "
53 "lookup failure |%s| or no match |%s|.\n",
54 __FILE__,
55 __func__,
56 __LINE__,
57 new_op->downcall.status ? "true" : "false",
58 match_handle(new_op->downcall.resp.lookup.refn.khandle,
59 inode) ? "false" : "true");
60 gossip_debug(GOSSIP_DCACHE_DEBUG,
61 "%s:%s:%d revalidate failed\n",
62 __FILE__, __func__, __LINE__);
63 goto out_drop;
64 }
65
66 ret = 1;
67out_release_op:
68 op_release(new_op);
69out_put_parent:
70 dput(parent_dentry);
71 return ret;
72out_drop:
73 d_drop(dentry);
74 goto out_release_op;
75}
76
77/*
78 * Verify that dentry is valid.
79 *
f987f4c2 80 * Should return 1 if dentry can still be trusted, else 0.
5db11c21 81 */
8bb8aefd 82static int orangefs_d_revalidate(struct dentry *dentry, unsigned int flags)
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83{
84 struct inode *inode;
85 int ret = 0;
86
87 if (flags & LOOKUP_RCU)
88 return -ECHILD;
89
90 gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: called on dentry %p.\n",
91 __func__, dentry);
92
93 /* find inode from dentry */
94 if (!dentry->d_inode) {
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95 gossip_debug(GOSSIP_DCACHE_DEBUG,
96 "%s: negative dentry.\n",
5db11c21 97 __func__);
f987f4c2 98 goto out;
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99 }
100
101 gossip_debug(GOSSIP_DCACHE_DEBUG, "%s: inode valid.\n", __func__);
102 inode = dentry->d_inode;
103
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104 /* skip root handle lookups. */
105 if (is_root_handle(inode)) {
106 ret = 1;
107 goto out;
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108 }
109
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110 /* lookup the object. */
111 if (orangefs_revalidate_lookup(dentry))
112 ret = 1;
113
114out:
115 return ret;
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116}
117
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118const struct dentry_operations orangefs_dentry_operations = {
119 .d_revalidate = orangefs_d_revalidate,
5db11c21 120};