[mirror_ubuntu-artful-kernel.git] / fs / gfs2 / acl.c

/*
 * Copyright (C) Sistina Software, Inc.  1997-2003 All rights reserved.
 * Copyright (C) 2004-2006 Red Hat, Inc.  All rights reserved.
 *
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU General Public License version 2.
 */

#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/xattr.h>
#include <linux/posix_acl.h>
#include <linux/posix_acl_xattr.h>
#include <linux/gfs2_ondisk.h>

#include "gfs2.h"
#include "incore.h"
#include "acl.h"
#include "xattr.h"
#include "glock.h"
#include "inode.h"
#include "meta_io.h"
#include "rgrp.h"
#include "trans.h"
#include "util.h"

static const char *gfs2_acl_name(int type)
{
	switch (type) {
	case ACL_TYPE_ACCESS:
		return XATTR_POSIX_ACL_ACCESS;
	case ACL_TYPE_DEFAULT:
		return XATTR_POSIX_ACL_DEFAULT;
	}
	return NULL;
}

static struct posix_acl *__gfs2_get_acl(struct inode *inode, int type)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct posix_acl *acl;
	const char *name;
	char *data;
	int len;

	if (!ip->i_eattr)
		return NULL;

	name = gfs2_acl_name(type);
	len = gfs2_xattr_acl_get(ip, name, &data);
	if (len <= 0)
		return ERR_PTR(len);
	acl = posix_acl_from_xattr(&init_user_ns, data, len);
	kfree(data);
	return acl;
}

struct posix_acl *gfs2_get_acl(struct inode *inode, int type)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder gh;
	bool need_unlock = false;
	struct posix_acl *acl;

	if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
		int ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
					     LM_FLAG_ANY, &gh);
		if (ret)
			return ERR_PTR(ret);
		need_unlock = true;
	}
	acl = __gfs2_get_acl(inode, type);
	if (need_unlock)
		gfs2_glock_dq_uninit(&gh);
	return acl;
}

int __gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
{
	int error;
	int len;
	char *data;
	const char *name = gfs2_acl_name(type);

	if (acl && acl->a_count > GFS2_ACL_MAX_ENTRIES(GFS2_SB(inode)))
		return -E2BIG;

	if (type == ACL_TYPE_ACCESS) {
		umode_t mode = inode->i_mode;

		error = posix_acl_update_mode(inode, &inode->i_mode, &acl);
		if (error)
			return error;
		if (mode != inode->i_mode)
			mark_inode_dirty(inode);
	}

	if (acl) {
		len = posix_acl_to_xattr(&init_user_ns, acl, NULL, 0);
		if (len == 0)
			return 0;
		data = kmalloc(len, GFP_NOFS);
		if (data == NULL)
			return -ENOMEM;
		error = posix_acl_to_xattr(&init_user_ns, acl, data, len);
		if (error < 0)
			goto out;
	} else {
		data = NULL;
		len = 0;
	}

	error = __gfs2_xattr_set(inode, name, data, len, 0, GFS2_EATYPE_SYS);
	if (error)
		goto out;
	set_cached_acl(inode, type, acl);
out:
	kfree(data);
	return error;
}

int gfs2_set_acl(struct inode *inode, struct posix_acl *acl, int type)
{
	struct gfs2_inode *ip = GFS2_I(inode);
	struct gfs2_holder gh;
	bool need_unlock = false;
	int ret;

	ret = gfs2_rsqa_alloc(ip);
	if (ret)
		return ret;

	if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
		ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
		if (ret)
			return ret;
		need_unlock = true;
	}
	ret = __gfs2_set_acl(inode, acl, type);
	if (need_unlock)
		gfs2_glock_dq_uninit(&gh);
	return ret;
}
Commit	Line	Data
b3b94faa DT	1	/*
b3b94faa DT	2	* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3a8a9a10	3	* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
b3b94faa DT	4	*
	5	* This copyrighted material is made available to anyone wishing to use,
	6	* modify, copy, or redistribute it subject to the terms and conditions
e9fc2aa0	7	* of the GNU General Public License version 2.
b3b94faa DT	8	*/
	9
	10	#include <linux/sched.h>
	11	#include <linux/slab.h>
	12	#include <linux/spinlock.h>
	13	#include <linux/completion.h>
	14	#include <linux/buffer_head.h>
2646a1f6	15	#include <linux/xattr.h>
b3b94faa DT	16	#include <linux/posix_acl.h>
b3b94faa DT	17	#include <linux/posix_acl_xattr.h>
5c676f6d	18	#include <linux/gfs2_ondisk.h>
b3b94faa DT	19
b3b94faa DT	20	#include "gfs2.h"
5c676f6d	21	#include "incore.h"
b3b94faa	22	#include "acl.h"
307cf6e6	23	#include "xattr.h"
b3b94faa DT	24	#include "glock.h"
	25	#include "inode.h"
	26	#include "meta_io.h"
1a39ba99	27	#include "rgrp.h"
b3b94faa	28	#include "trans.h"
5c676f6d	29	#include "util.h"
b3b94faa	30
479c427d	31	static const char *gfs2_acl_name(int type)
b3b94faa	32	{
479c427d SW	33	switch (type) {
479c427d SW	34	case ACL_TYPE_ACCESS:
97d79299	35	return XATTR_POSIX_ACL_ACCESS;
479c427d	36	case ACL_TYPE_DEFAULT:
97d79299	37	return XATTR_POSIX_ACL_DEFAULT;
479c427d SW	38	}
	39	return NULL;
	40	}
b3b94faa	41
1a39ba99	42	static struct posix_acl __gfs2_get_acl(struct inode inode, int type)
479c427d	43	{
018a01cd	44	struct gfs2_inode *ip = GFS2_I(inode);
479c427d SW	45	struct posix_acl *acl;
	46	const char *name;
	47	char *data;
	48	int len;
40b78a32	49
3767ac21	50	if (!ip->i_eattr)
479c427d	51	return NULL;
b3b94faa	52
479c427d	53	name = gfs2_acl_name(type);
479c427d	54	len = gfs2_xattr_acl_get(ip, name, &data);
1a39ba99	55	if (len <= 0)
479c427d	56	return ERR_PTR(len);
5f3a4a28	57	acl = posix_acl_from_xattr(&init_user_ns, data, len);
479c427d SW	58	kfree(data);
479c427d SW	59	return acl;
b3b94faa DT	60	}
b3b94faa DT	61
1a39ba99 AV	62	struct posix_acl gfs2_get_acl(struct inode inode, int type)
	63	{
	64	struct gfs2_inode *ip = GFS2_I(inode);
	65	struct gfs2_holder gh;
	66	bool need_unlock = false;
	67	struct posix_acl *acl;
	68
	69	if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
	70	int ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
	71	LM_FLAG_ANY, &gh);
	72	if (ret)
	73	return ERR_PTR(ret);
	74	need_unlock = true;
	75	}
	76	acl = __gfs2_get_acl(inode, type);
	77	if (need_unlock)
	78	gfs2_glock_dq_uninit(&gh);
	79	return acl;
	80	}
	81
	82	int __gfs2_set_acl(struct inode inode, struct posix_acl acl, int type)
b3b94faa	83	{
b3b94faa	84	int error;
479c427d SW	85	int len;
	86	char *data;
	87	const char *name = gfs2_acl_name(type);
	88
27870207	89	if (acl && acl->a_count > GFS2_ACL_MAX_ENTRIES(GFS2_SB(inode)))
f2113eb8	90	return -E2BIG;
2646a1f6 SW	91
2646a1f6 SW	92	if (type == ACL_TYPE_ACCESS) {
d6952123	93	umode_t mode = inode->i_mode;
e01580bf	94
07393101 JK	95	error = posix_acl_update_mode(inode, &inode->i_mode, &acl);
07393101 JK	96	if (error)
e01580bf	97	return error;
07393101	98	if (mode != inode->i_mode)
733dbc1b	99	mark_inode_dirty(inode);
2646a1f6 SW	100	}
2646a1f6 SW	101
e01580bf CH	102	if (acl) {
	103	len = posix_acl_to_xattr(&init_user_ns, acl, NULL, 0);
	104	if (len == 0)
	105	return 0;
	106	data = kmalloc(len, GFP_NOFS);
	107	if (data == NULL)
	108	return -ENOMEM;
	109	error = posix_acl_to_xattr(&init_user_ns, acl, data, len);
	110	if (error < 0)
	111	goto out;
	112	} else {
	113	data = NULL;
	114	len = 0;
106381bf	115	}
e01580bf CH	116
	117	error = __gfs2_xattr_set(inode, name, data, len, 0, GFS2_EATYPE_SYS);
	118	if (error)
	119	goto out;
932e468a	120	set_cached_acl(inode, type, acl);
2646a1f6	121	out:
e01580bf	122	kfree(data);
2646a1f6 SW	123	return error;
2646a1f6 SW	124	}
1a39ba99 AV	125
	126	int gfs2_set_acl(struct inode inode, struct posix_acl acl, int type)
	127	{
	128	struct gfs2_inode *ip = GFS2_I(inode);
	129	struct gfs2_holder gh;
	130	bool need_unlock = false;
	131	int ret;
	132
	133	ret = gfs2_rsqa_alloc(ip);
	134	if (ret)
	135	return ret;
	136
	137	if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
	138	ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
	139	if (ret)
	140	return ret;
	141	need_unlock = true;
	142	}
	143	ret = __gfs2_set_acl(inode, acl, type);
	144	if (need_unlock)
	145	gfs2_glock_dq_uninit(&gh);
	146	return ret;
	147	}