/*
 * 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);
}

/* 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);
}

e-remove&amp;id=3e03d7ccf4418c87a134bbfa79c05090296767f7'>net</a>/<a href='/cgit.cgi/linux/net-next.git/log/net/sunrpc?h=nds-private-remove&amp;id=3e03d7ccf4418c87a134bbfa79c05090296767f7'>sunrpc</a>/<a href='/cgit.cgi/linux/net-next.git/log/net/sunrpc/auth_gss?h=nds-private-remove&amp;id=3e03d7ccf4418c87a134bbfa79c05090296767f7'>auth_gss</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/net/sunrpc/auth_gss?h=nds-private-remove&amp;id=3e03d7ccf4418c87a134bbfa79c05090296767f7&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>
<tr><td><span title='2017-01-31 12:29:24 -0500'>2017-01-31</span></td><td><a href='/cgit.cgi/linux/net-next.git/commit/net/sunrpc/auth_gss?h=nds-private-remove&amp;id=034dd34ff4916ec1f8f74e39ca3efb04eab2f791'>svcrpc: fix oops in absence of krb5 module</a></td><td>J. Bruce Fields</td><td>1</td><td><span class='deletions'>-1</span>/<span class='insertions'>+1</span></td></tr>
alue='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2016-12-25 14:05:56 -0800</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2016-12-25 14:05:56 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/trace/events/signal.h?id=b272f732f888d4cf43c943a40c9aaa836f9b7431'>b272f732f888d4cf43c943a40c9aaa836f9b7431</a> (<a href='/cgit.cgi/linux/net-next.git/patch/include/trace/events/signal.h?id=b272f732f888d4cf43c943a40c9aaa836f9b7431'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=b272f732f888d4cf43c943a40c9aaa836f9b7431'>da9cac6b9d12b83592c16d3503c0e3f2f00f146f</a> /<a href='/cgit.cgi/linux/net-next.git/tree/include/trace/events/signal.h?id=b272f732f888d4cf43c943a40c9aaa836f9b7431'>include/trace/events/signal.h</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/trace/events/signal.h?id=10bbe7599e2755d3f3e100103967788b8b5a4bce'>10bbe7599e2755d3f3e100103967788b8b5a4bce</a> (<a href='/cgit.cgi/linux/net-next.git/diff/include/trace/events/signal.h?id=b272f732f888d4cf43c943a40c9aaa836f9b7431&amp;id2=10bbe7599e2755d3f3e100103967788b8b5a4bce'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/include/trace/events/signal.h?id=008b69e4d52f2cbee3ed0d0502edd78155000b1a'>008b69e4d52f2cbee3ed0d0502edd78155000b1a</a> (<a href='/cgit.cgi/linux/net-next.git/diff/include/trace/events/signal.h?id=b272f732f888d4cf43c943a40c9aaa836f9b7431&amp;id2=008b69e4d52f2cbee3ed0d0502edd78155000b1a'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge branch 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</div><div class='commit-msg'>Pull SMP hotplug notifier removal from Thomas Gleixner:
 "This is the final cleanup of the hotplug notifier infrastructure. The
  series has been reintgrated in the last two days because there came a
  new driver using the old infrastructure via the SCSI tree.

  Summary:

   - convert the last leftover drivers utilizing notifiers

   - fixup for a completely broken hotplug user

   - prevent setup of already used states

   - removal of the notifiers

   - treewide cleanup of hotplug state names

   - consolidation of state space

  There is a sphinx based documentation pending, but that needs review
  from the documentation folks"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/armada-xp: Consolidate hotplug state space
  irqchip/gic: Consolidate hotplug state space
  coresight/etm3/4x: Consolidate hotplug state space
  cpu/hotplug: Cleanup state names
  cpu/hotplug: Remove obsolete cpu hotplug register/unregister functions
  staging/lustre/libcfs: Convert to hotplug state machine
  scsi/bnx2i: Convert to hotplug state machine
  scsi/bnx2fc: Convert to hotplug state machine
  cpu/hotplug: Prevent overwriting of callbacks
  x86/msr: Remove bogus cleanup from the error path
  bus: arm-ccn: Prevent hotplug callback leak
  perf/x86/intel/cstate: Prevent hotplug callback leak
  ARM/imx/mmcd: Fix broken cpu hotplug handling
  scsi: qedi: Convert to hotplug state machine
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=b272f732f888d4cf43c943a40c9aaa836f9b7431'>Diffstat</a> (limited to 'include/trace/events/signal.h')</div><table summary='diffstat' class='diffstat'>