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	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
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/*
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 * Cache operations for Coda.
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 * For Linux 2.1: (C) 1997 Carnegie Mellon University
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 * For Linux 2.3: (C) 2000 Carnegie Mellon University
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 *
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 * Carnegie Mellon encourages users of this code to contribute improvements
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 * to the Coda project http://www.coda.cs.cmu.edu/ <coda@cs.cmu.edu>.
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 */
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/time.h>
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#include <linux/fs.h>
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#include <linux/stat.h>
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#include <linux/errno.h>
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#include <linux/uaccess.h>
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#include <linux/string.h>
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#include <linux/list.h>
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#include <linux/sched.h>
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#include <linux/spinlock.h>
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#include <linux/coda.h>
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#include "coda_psdev.h"
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#include "coda_linux.h"
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#include "coda_cache.h"
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static atomic_t permission_epoch = ATOMIC_INIT(0);
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/* replace or extend an acl cache hit */
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void coda_cache_enter(struct inode *inode, int mask)
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{
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	struct coda_inode_info *cii = ITOC(inode);
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	spin_lock(&cii->c_lock);
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	cii->c_cached_epoch = atomic_read(&permission_epoch);
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	if (!uid_eq(cii->c_uid, current_fsuid())) {
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		cii->c_uid = current_fsuid();
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                cii->c_cached_perm = mask;
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        } else
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                cii->c_cached_perm |= mask;
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	spin_unlock(&cii->c_lock);
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}
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/* remove cached acl from an inode */
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void coda_cache_clear_inode(struct inode *inode)
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{
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	struct coda_inode_info *cii = ITOC(inode);
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	spin_lock(&cii->c_lock);
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	cii->c_cached_epoch = atomic_read(&permission_epoch) - 1;
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	spin_unlock(&cii->c_lock);
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}
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/* remove all acl caches */
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void coda_cache_clear_all(struct super_block *sb)
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{
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	atomic_inc(&permission_epoch);
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}
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/* check if the mask has been matched against the acl already */
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int coda_cache_check(struct inode *inode, int mask)
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{
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	struct coda_inode_info *cii = ITOC(inode);
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	int hit;
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	spin_lock(&cii->c_lock);
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	hit = (mask & cii->c_cached_perm) == mask &&
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	    uid_eq(cii->c_uid, current_fsuid()) &&
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	    cii->c_cached_epoch == atomic_read(&permission_epoch);
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	spin_unlock(&cii->c_lock);
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	return hit;
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}
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/* Purging dentries and children */
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/* The following routines drop dentries which are not
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   in use and flag dentries which are in use to be 
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   zapped later.
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   The flags are detected by:
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   - coda_dentry_revalidate (for lookups) if the flag is C_PURGE
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   - coda_dentry_delete: to remove dentry from the cache when d_count
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     falls to zero
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   - an inode method coda_revalidate (for attributes) if the 
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     flag is C_VATTR
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*/
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/* this won't do any harm: just flag all children */
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static void coda_flag_children(struct dentry *parent, int flag)
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{
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	struct dentry *de;
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	spin_lock(&parent->d_lock);
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	list_for_each_entry(de, &parent->d_subdirs, d_child) {
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		/* don't know what to do with negative dentries */
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		if (d_inode(de) ) 
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			coda_flag_inode(d_inode(de), flag);
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	}
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	spin_unlock(&parent->d_lock);
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	return; 
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}
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void coda_flag_inode_children(struct inode *inode, int flag)
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{
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	struct dentry *alias_de;
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	if ( !inode || !S_ISDIR(inode->i_mode)) 
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		return; 
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	alias_de = d_find_alias(inode);
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	if (!alias_de)
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		return;
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	coda_flag_children(alias_de, flag);
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	shrink_dcache_parent(alias_de);
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	dput(alias_de);
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}
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