mirror of
https://github.com/torvalds/linux
synced 2024-11-05 18:23:50 +00:00
8fc8b9df83
Move include/linux/coda_psdev.h to fs/coda/ as there's nothing else that uses it. Link: http://lkml.kernel.org/r/3ceeee0415a929b89fb02700b6b4b3a07938acb8.1558117389.git.jaharkes@cs.cmu.edu Link: https://patchwork.kernel.org/patch/10590257/ Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu> Cc: Yann Droneaud <ydroneaud@opteya.com> Cc: Jan Harkes <jaharkes@cs.cmu.edu> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Colin Ian King <colin.king@canonical.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Fabian Frederick <fabf@skynet.be> Cc: Mikko Rapeli <mikko.rapeli@iki.fi> Cc: Sam Protsenko <semen.protsenko@linaro.org> Cc: Zhouyang Jia <jiazhouyang09@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
119 lines
3 KiB
C
119 lines
3 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* 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 "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);
|
|
}
|
|
|
|
/* 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);
|
|
}
|
|
|
|
/* remove all acl caches */
|
|
void coda_cache_clear_all(struct super_block *sb)
|
|
{
|
|
atomic_inc(&permission_epoch);
|
|
}
|
|
|
|
|
|
/* 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;
|
|
}
|
|
|
|
|
|
/* 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;
|
|
}
|
|
|
|
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);
|
|
}
|
|
|