alistair23-linux/fs/coda/cache.c
Alexey Dobriyan e8edc6e03a Detach sched.h from mm.h
First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.

This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
   getting them indirectly

Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
   they don't need sched.h
b) sched.h stops being dependency for significant number of files:
   on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
   after patch it's only 3744 (-8.3%).

Cross-compile tested on

	all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
	alpha alpha-up
	arm
	i386 i386-up i386-defconfig i386-allnoconfig
	ia64 ia64-up
	m68k
	mips
	parisc parisc-up
	powerpc powerpc-up
	s390 s390-up
	sparc sparc-up
	sparc64 sparc64-up
	um-x86_64
	x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig

as well as my two usual configs.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-21 09:18:19 -07:00

122 lines
3 KiB
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 <asm/uaccess.h>
#include <linux/string.h>
#include <linux/list.h>
#include <linux/sched.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>
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);
cii->c_cached_epoch = atomic_read(&permission_epoch);
if (cii->c_uid != current->fsuid) {
cii->c_uid = current->fsuid;
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);
cii->c_cached_perm = 0;
}
/* remove all acl caches */
void coda_cache_clear_all(struct super_block *sb)
{
struct coda_sb_info *sbi;
sbi = coda_sbp(sb);
BUG_ON(!sbi);
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;
hit = (mask & cii->c_cached_perm) == mask &&
cii->c_uid == current->fsuid &&
cii->c_cached_epoch == atomic_read(&permission_epoch);
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_u.d_child);
/* don't know what to do with negative dentries */
if ( ! de->d_inode )
continue;
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;
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);
}