Release 4.11 fs/coda/cache.c

/*
 * 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/time.h>
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/errno.h>
#include <linux/uaccess.h>
#include <linux/string.h>
#include <linux/list.h>
#include <linux/sched.h>
#include <linux/spinlock.h>

#include <linux/coda.h>
#include <linux/coda_psdev.h>
#include "coda_linux.h"
#include "coda_cache.h"


static atomic_t permission_epoch = ATOMIC_INIT(0);

/* replace or extend an acl cache hit */


void coda_cache_enter(struct inode *inode, int mask)
{
	struct coda_inode_info *cii = ITOC(inode);

	spin_lock(&cii->c_lock);
	cii->c_cached_epoch = atomic_read(&permission_epoch);
	if (!uid_eq(cii->c_uid, current_fsuid())) {
		cii->c_uid = current_fsuid();
                cii->c_cached_perm = mask;
        } else
                cii->c_cached_perm |= mask;
	spin_unlock(&cii->c_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
46
54.76%
5
50.00%
Yoshihisa Abe
16
19.05%
1
10.00%
Jan Harkes
13
15.48%
2
20.00%
Eric W. Biedermann
5
5.95%
1
10.00%
David Howells
4
4.76%
1
10.00%
Total
84
100.00%
10
100.00%

/* remove cached acl from an inode */


void coda_cache_clear_inode(struct inode *inode)
{
	struct coda_inode_info *cii = ITOC(inode);
	spin_lock(&cii->c_lock);
	cii->c_cached_epoch = atomic_read(&permission_epoch) - 1;
	spin_unlock(&cii->c_lock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
24
50.00%
4
66.67%
Yoshihisa Abe
16
33.33%
1
16.67%
Jan Harkes
8
16.67%
1
16.67%
Total
48
100.00%
6
100.00%

/* remove all acl caches */


void coda_cache_clear_all(struct super_block *sb)
{
	atomic_inc(&permission_epoch);
}


Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
14
87.50%
1
50.00%
Jan Harkes
2
12.50%
1
50.00%
Total
16
100.00%
2
100.00%

/* 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;
	
	spin_lock(&cii->c_lock);
	hit = (mask & cii->c_cached_perm) == mask &&
	    uid_eq(cii->c_uid, current_fsuid()) &&
	    cii->c_cached_epoch == atomic_read(&permission_epoch);
	spin_unlock(&cii->c_lock);

	return hit;
}


Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
44
57.14%
4
44.44%
Yoshihisa Abe
16
20.78%
1
11.11%
Jan Harkes
11
14.29%
2
22.22%
Eric W. Biedermann
4
5.19%
1
11.11%
David Howells
2
2.60%
1
11.11%
Total
77
100.00%
9
100.00%

/* 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 dentry *de;

	spin_lock(&parent->d_lock);
	list_for_each_entry(de, &parent->d_subdirs, d_child) {
		/* don't know what to do with negative dentries */
		if (d_inode(de) ) 
			coda_flag_inode(d_inode(de), flag);
	}
	spin_unlock(&parent->d_lock);
	return; 
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
42
65.62%
5
55.56%
Nicholas Piggin
12
18.75%
1
11.11%
David Howells
6
9.38%
1
11.11%
Al Viro
4
6.25%
2
22.22%
Total
64
100.00%
9
100.00%



void coda_flag_inode_children(struct inode *inode, int flag)
{
	struct dentry *alias_de;

	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);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
62
100.00%
6
100.00%
Total
62
100.00%
6
100.00%

Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Linus Torvalds (pre-git)
273
66.10%
11
42.31%
Yoshihisa Abe
51
12.35%
1
3.85%
Jan Harkes
44
10.65%
3
11.54%
David Howells
12
2.91%
2
7.69%
Nicholas Piggin
12
2.91%
1
3.85%
Eric W. Biedermann
9
2.18%
1
3.85%
Al Viro
6
1.45%
3
11.54%
Alexey Dobriyan
3
0.73%
1
3.85%
Linus Torvalds
1
0.24%
1
3.85%
Fabian Frederick
1
0.24%
1
3.85%
Dave Jones
1
0.24%
1
3.85%
Total
413
100.00%
26
100.00%
Directory: fs/coda

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.