1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
|
/*
* Cache operations for Coda.
* For Linux 2.1: (C) 1997 Carnegie Mellon University
* For Linux 2.3: (C) 2000 Carnegie Mellon University
*
* Carnegie Mellon encourages users of this code to contribute improvements
* to the Coda project http://www.coda.cs.cmu.edu/ <coda@cs.cmu.edu>.
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/locks.h>
#include <asm/segment.h>
#include <asm/uaccess.h>
#include <linux/string.h>
#include <linux/list.h>
#include <linux/coda.h>
#include <linux/coda_linux.h>
#include <linux/coda_psdev.h>
#include <linux/coda_fs_i.h>
#include <linux/coda_cache.h>
/* replace or extend an acl cache hit */
void coda_cache_enter(struct inode *inode, int mask)
{
struct coda_inode_info *cii = ITOC(inode);
ENTRY;
if ( !coda_cred_ok(&cii->c_cached_cred) ) {
coda_load_creds(&cii->c_cached_cred);
cii->c_cached_perm = mask;
} else
cii->c_cached_perm |= mask;
}
/* remove cached acl from an inode */
void coda_cache_clear_inode(struct inode *inode)
{
struct coda_inode_info *cii = ITOC(inode);
ENTRY;
cii->c_cached_perm = 0;
}
/* remove all acl caches for a principal (or all principals when cred == NULL)*/
void coda_cache_clear_all(struct super_block *sb, struct coda_cred *cred)
{
struct coda_sb_info *sbi;
struct coda_inode_info *cii;
struct list_head *tmp;
ENTRY;
sbi = coda_sbp(sb);
if (!sbi) BUG();
list_for_each(tmp, &sbi->sbi_cihead)
{
cii = list_entry(tmp, struct coda_inode_info, c_cilist);
if (!cred || coda_cred_eq(cred, &cii->c_cached_cred))
cii->c_cached_perm = 0;
}
}
/* check if the mask has been matched against the acl already */
int coda_cache_check(struct inode *inode, int mask)
{
struct coda_inode_info *cii = ITOC(inode);
int hit;
hit = ((mask & cii->c_cached_perm) == mask) &&
coda_cred_ok(&cii->c_cached_cred);
CDEBUG(D_CACHE, "%s for ino %ld\n", hit ? "HIT" : "MISS", inode->i_ino);
return hit;
}
/* Purging dentries and children */
/* The following routines drop dentries which are not
in use and flag dentries which are in use to be
zapped later.
The flags are detected by:
- coda_dentry_revalidate (for lookups) if the flag is C_PURGE
- coda_dentry_delete: to remove dentry from the cache when d_count
falls to zero
- an inode method coda_revalidate (for attributes) if the
flag is C_VATTR
*/
/* this won't do any harm: just flag all children */
static void coda_flag_children(struct dentry *parent, int flag)
{
struct list_head *child;
struct dentry *de;
spin_lock(&dcache_lock);
list_for_each(child, &parent->d_subdirs)
{
de = list_entry(child, struct dentry, d_child);
/* don't know what to do with negative dentries */
if ( ! de->d_inode )
continue;
CDEBUG(D_DOWNCALL, "%d for %*s/%*s\n", flag,
de->d_name.len, de->d_name.name,
de->d_parent->d_name.len, de->d_parent->d_name.name);
coda_flag_inode(de->d_inode, flag);
}
spin_unlock(&dcache_lock);
return;
}
void coda_flag_inode_children(struct inode *inode, int flag)
{
struct dentry *alias_de;
ENTRY;
if ( !inode || !S_ISDIR(inode->i_mode))
return;
alias_de = d_find_alias(inode);
if (!alias_de)
return;
coda_flag_children(alias_de, flag);
shrink_dcache_parent(alias_de);
dput(alias_de);
}
|
