1 // SPDX-License-Identifier: GPL-2.0 <<
2 /* 1 /*
3 * Cache operations for Coda. 2 * Cache operations for Coda.
4 * For Linux 2.1: (C) 1997 Carnegie Mellon Uni 3 * For Linux 2.1: (C) 1997 Carnegie Mellon University
5 * For Linux 2.3: (C) 2000 Carnegie Mellon Uni 4 * For Linux 2.3: (C) 2000 Carnegie Mellon University
6 * 5 *
7 * Carnegie Mellon encourages users of this co 6 * Carnegie Mellon encourages users of this code to contribute improvements
8 * to the Coda project http://www.coda.cs.cmu. 7 * to the Coda project http://www.coda.cs.cmu.edu/ <coda@cs.cmu.edu>.
9 */ 8 */
10 9
11 #include <linux/types.h> 10 #include <linux/types.h>
12 #include <linux/kernel.h> 11 #include <linux/kernel.h>
13 #include <linux/time.h> 12 #include <linux/time.h>
14 #include <linux/fs.h> 13 #include <linux/fs.h>
15 #include <linux/stat.h> 14 #include <linux/stat.h>
16 #include <linux/errno.h> 15 #include <linux/errno.h>
17 #include <linux/uaccess.h> !! 16 #include <asm/uaccess.h>
18 #include <linux/string.h> 17 #include <linux/string.h>
19 #include <linux/list.h> 18 #include <linux/list.h>
20 #include <linux/sched.h> <<
21 #include <linux/spinlock.h> <<
22 19
23 #include <linux/coda.h> 20 #include <linux/coda.h>
24 #include "coda_psdev.h" !! 21 #include <linux/coda_linux.h>
25 #include "coda_linux.h" !! 22 #include <linux/coda_psdev.h>
26 #include "coda_cache.h" !! 23 #include <linux/coda_fs_i.h>
>> 24 #include <linux/coda_cache.h>
27 25
28 static atomic_t permission_epoch = ATOMIC_INIT 26 static atomic_t permission_epoch = ATOMIC_INIT(0);
29 27
30 /* replace or extend an acl cache hit */ 28 /* replace or extend an acl cache hit */
31 void coda_cache_enter(struct inode *inode, int 29 void coda_cache_enter(struct inode *inode, int mask)
32 { 30 {
33 struct coda_inode_info *cii = ITOC(ino 31 struct coda_inode_info *cii = ITOC(inode);
34 32
35 spin_lock(&cii->c_lock); <<
36 cii->c_cached_epoch = atomic_read(&per 33 cii->c_cached_epoch = atomic_read(&permission_epoch);
37 if (!uid_eq(cii->c_uid, current_fsuid( !! 34 if (cii->c_uid != current->fsuid) {
38 cii->c_uid = current_fsuid(); !! 35 cii->c_uid = current->fsuid;
39 cii->c_cached_perm = mask; 36 cii->c_cached_perm = mask;
40 } else 37 } else
41 cii->c_cached_perm |= mask; 38 cii->c_cached_perm |= mask;
42 spin_unlock(&cii->c_lock); <<
43 } 39 }
44 40
45 /* remove cached acl from an inode */ 41 /* remove cached acl from an inode */
46 void coda_cache_clear_inode(struct inode *inod 42 void coda_cache_clear_inode(struct inode *inode)
47 { 43 {
48 struct coda_inode_info *cii = ITOC(ino 44 struct coda_inode_info *cii = ITOC(inode);
49 spin_lock(&cii->c_lock); !! 45 cii->c_cached_perm = 0;
50 cii->c_cached_epoch = atomic_read(&per <<
51 spin_unlock(&cii->c_lock); <<
52 } 46 }
53 47
54 /* remove all acl caches */ 48 /* remove all acl caches */
55 void coda_cache_clear_all(struct super_block * 49 void coda_cache_clear_all(struct super_block *sb)
56 { 50 {
>> 51 struct coda_sb_info *sbi;
>> 52
>> 53 sbi = coda_sbp(sb);
>> 54 if (!sbi) BUG();
>> 55
57 atomic_inc(&permission_epoch); 56 atomic_inc(&permission_epoch);
58 } 57 }
59 58
60 59
61 /* check if the mask has been matched against 60 /* check if the mask has been matched against the acl already */
62 int coda_cache_check(struct inode *inode, int 61 int coda_cache_check(struct inode *inode, int mask)
63 { 62 {
64 struct coda_inode_info *cii = ITOC(ino 63 struct coda_inode_info *cii = ITOC(inode);
65 int hit; !! 64 int hit;
66 65
67 spin_lock(&cii->c_lock); !! 66 hit = (mask & cii->c_cached_perm) == mask &&
68 hit = (mask & cii->c_cached_perm) == m !! 67 cii->c_uid == current->fsuid &&
69 uid_eq(cii->c_uid, current_fsuid() !! 68 cii->c_cached_epoch == atomic_read(&permission_epoch);
70 cii->c_cached_epoch == atomic_read <<
71 spin_unlock(&cii->c_lock); <<
72 69
73 return hit; !! 70 return hit;
74 } 71 }
75 72
76 73
77 /* Purging dentries and children */ 74 /* Purging dentries and children */
78 /* The following routines drop dentries which 75 /* The following routines drop dentries which are not
79 in use and flag dentries which are in use t 76 in use and flag dentries which are in use to be
80 zapped later. 77 zapped later.
81 78
82 The flags are detected by: 79 The flags are detected by:
83 - coda_dentry_revalidate (for lookups) if t 80 - coda_dentry_revalidate (for lookups) if the flag is C_PURGE
84 - coda_dentry_delete: to remove dentry from 81 - coda_dentry_delete: to remove dentry from the cache when d_count
85 falls to zero 82 falls to zero
86 - an inode method coda_revalidate (for attr 83 - an inode method coda_revalidate (for attributes) if the
87 flag is C_VATTR 84 flag is C_VATTR
88 */ 85 */
89 86
90 /* this won't do any harm: just flag all child 87 /* this won't do any harm: just flag all children */
91 static void coda_flag_children(struct dentry * 88 static void coda_flag_children(struct dentry *parent, int flag)
92 { 89 {
>> 90 struct list_head *child;
93 struct dentry *de; 91 struct dentry *de;
94 92
95 spin_lock(&parent->d_lock); !! 93 spin_lock(&dcache_lock);
96 hlist_for_each_entry(de, &parent->d_ch !! 94 list_for_each(child, &parent->d_subdirs)
97 struct inode *inode = d_inode_ !! 95 {
>> 96 de = list_entry(child, struct dentry, d_child);
98 /* don't know what to do with 97 /* don't know what to do with negative dentries */
99 if (inode) !! 98 if ( ! de->d_inode )
100 coda_flag_inode(inode, !! 99 continue;
>> 100 coda_flag_inode(de->d_inode, flag);
101 } 101 }
102 spin_unlock(&parent->d_lock); !! 102 spin_unlock(&dcache_lock);
>> 103 return;
103 } 104 }
104 105
105 void coda_flag_inode_children(struct inode *in 106 void coda_flag_inode_children(struct inode *inode, int flag)
106 { 107 {
107 struct dentry *alias_de; 108 struct dentry *alias_de;
108 109
109 if ( !inode || !S_ISDIR(inode->i_mode) 110 if ( !inode || !S_ISDIR(inode->i_mode))
110 return; 111 return;
111 112
112 alias_de = d_find_alias(inode); 113 alias_de = d_find_alias(inode);
113 if (!alias_de) 114 if (!alias_de)
114 return; 115 return;
115 coda_flag_children(alias_de, flag); 116 coda_flag_children(alias_de, flag);
116 shrink_dcache_parent(alias_de); 117 shrink_dcache_parent(alias_de);
117 dput(alias_de); 118 dput(alias_de);
118 } 119 }
119 120
120 121
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