[mirror_ubuntu-bionic-kernel.git] / fs / 9p / acl.c

/*
 * Copyright IBM Corporation, 2010
 * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2.1 of the GNU Lesser General Public License
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 */

#include <linux/module.h>
#include <linux/fs.h>
#include <net/9p/9p.h>
#include <net/9p/client.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/posix_acl_xattr.h>
#include "xattr.h"
#include "acl.h"
#include "v9fs.h"
#include "v9fs_vfs.h"

static struct posix_acl *__v9fs_get_acl(struct p9_fid *fid, char *name)
{
	ssize_t size;
	void *value = NULL;
	struct posix_acl *acl = NULL;

	size = v9fs_fid_xattr_get(fid, name, NULL, 0);
	if (size > 0) {
		value = kzalloc(size, GFP_NOFS);
		if (!value)
			return ERR_PTR(-ENOMEM);
		size = v9fs_fid_xattr_get(fid, name, value, size);
		if (size > 0) {
			acl = posix_acl_from_xattr(value, size);
			if (IS_ERR(acl))
				goto err_out;
		}
	} else if (size == -ENODATA || size == 0 ||
		   size == -ENOSYS || size == -EOPNOTSUPP) {
		acl = NULL;
	} else
		acl = ERR_PTR(-EIO);

err_out:
	kfree(value);
	return acl;
}

int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)
{
	int retval = 0;
	struct posix_acl *pacl, *dacl;
	struct v9fs_session_info *v9ses;

	v9ses = v9fs_inode2v9ses(inode);
	if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
			((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
		set_cached_acl(inode, ACL_TYPE_DEFAULT, NULL);
		set_cached_acl(inode, ACL_TYPE_ACCESS, NULL);
		return 0;
	}
	/* get the default/access acl values and cache them */
	dacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_DEFAULT);
	pacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_ACCESS);

	if (!IS_ERR(dacl) && !IS_ERR(pacl)) {
		set_cached_acl(inode, ACL_TYPE_DEFAULT, dacl);
		set_cached_acl(inode, ACL_TYPE_ACCESS, pacl);
	} else
		retval = -EIO;

	if (!IS_ERR(dacl))
		posix_acl_release(dacl);

	if (!IS_ERR(pacl))
		posix_acl_release(pacl);

	return retval;
}

static struct posix_acl *v9fs_get_cached_acl(struct inode *inode, int type)
{
	struct posix_acl *acl;
	/*
	 * 9p Always cache the acl value when
	 * instantiating the inode (v9fs_inode_from_fid)
	 */
	acl = get_cached_acl(inode, type);
	BUG_ON(acl == ACL_NOT_CACHED);
	return acl;
}

struct posix_acl *v9fs_iop_get_acl(struct inode *inode, int type)
{
	struct v9fs_session_info *v9ses;

	v9ses = v9fs_inode2v9ses(inode);
	if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
			((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
		/*
		 * On access = client  and acl = on mode get the acl
		 * values from the server
		 */
		return NULL;
	}
	return v9fs_get_cached_acl(inode, type);

}

static int v9fs_set_acl(struct dentry *dentry, int type, struct posix_acl *acl)
{
	int retval;
	char *name;
	size_t size;
	void *buffer;
	struct inode *inode = dentry->d_inode;

	set_cached_acl(inode, type, acl);

	if (!acl)
		return 0;

	/* Set a setxattr request to server */
	size = posix_acl_xattr_size(acl->a_count);
	buffer = kmalloc(size, GFP_KERNEL);
	if (!buffer)
		return -ENOMEM;
	retval = posix_acl_to_xattr(acl, buffer, size);
	if (retval < 0)
		goto err_free_out;
	switch (type) {
	case ACL_TYPE_ACCESS:
		name = POSIX_ACL_XATTR_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		name = POSIX_ACL_XATTR_DEFAULT;
		break;
	default:
		BUG();
	}
	retval = v9fs_xattr_set(dentry, name, buffer, size, 0);
err_free_out:
	kfree(buffer);
	return retval;
}

int v9fs_acl_chmod(struct dentry *dentry)
{
	int retval = 0;
	struct posix_acl *acl;
	struct inode *inode = dentry->d_inode;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;
	acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);
	if (acl) {
		retval = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
		if (retval)
			return retval;
		retval = v9fs_set_acl(dentry, ACL_TYPE_ACCESS, acl);
		posix_acl_release(acl);
	}
	return retval;
}

int v9fs_set_create_acl(struct dentry *dentry,
			struct posix_acl **dpacl, struct posix_acl **pacl)
{
	if (dentry) {
		v9fs_set_acl(dentry, ACL_TYPE_DEFAULT, *dpacl);
		v9fs_set_acl(dentry, ACL_TYPE_ACCESS, *pacl);
	}
	posix_acl_release(*dpacl);
	posix_acl_release(*pacl);
	*dpacl = *pacl = NULL;
	return 0;
}

int v9fs_acl_mode(struct inode *dir, umode_t *modep,
		  struct posix_acl **dpacl, struct posix_acl **pacl)
{
	int retval = 0;
	umode_t mode = *modep;
	struct posix_acl *acl = NULL;

	if (!S_ISLNK(mode)) {
		acl = v9fs_get_cached_acl(dir, ACL_TYPE_DEFAULT);
		if (IS_ERR(acl))
			return PTR_ERR(acl);
		if (!acl)
			mode &= ~current_umask();
	}
	if (acl) {
		if (S_ISDIR(mode))
			*dpacl = posix_acl_dup(acl);
		retval = posix_acl_create(&acl, GFP_NOFS, &mode);
		if (retval < 0)
			return retval;
		if (retval > 0)
			*pacl = acl;
		else
			posix_acl_release(acl);
	}
	*modep  = mode;
	return 0;
}

static int v9fs_remote_get_acl(struct dentry *dentry, const char *name,
			       void *buffer, size_t size, int type)
{
	char *full_name;

	switch (type) {
	case ACL_TYPE_ACCESS:
		full_name =  POSIX_ACL_XATTR_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		full_name = POSIX_ACL_XATTR_DEFAULT;
		break;
	default:
		BUG();
	}
	return v9fs_xattr_get(dentry, full_name, buffer, size);
}

static int v9fs_xattr_get_acl(struct dentry *dentry, const char *name,
			      void *buffer, size_t size, int type)
{
	struct v9fs_session_info *v9ses;
	struct posix_acl *acl;
	int error;

	if (strcmp(name, "") != 0)
		return -EINVAL;

	v9ses = v9fs_dentry2v9ses(dentry);
	/*
	 * We allow set/get/list of acl when access=client is not specified
	 */
	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
		return v9fs_remote_get_acl(dentry, name, buffer, size, type);

	acl = v9fs_get_cached_acl(dentry->d_inode, type);
	if (IS_ERR(acl))
		return PTR_ERR(acl);
	if (acl == NULL)
		return -ENODATA;
	error = posix_acl_to_xattr(acl, buffer, size);
	posix_acl_release(acl);

	return error;
}

static int v9fs_remote_set_acl(struct dentry *dentry, const char *name,
			      const void *value, size_t size,
			      int flags, int type)
{
	char *full_name;

	switch (type) {
	case ACL_TYPE_ACCESS:
		full_name =  POSIX_ACL_XATTR_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		full_name = POSIX_ACL_XATTR_DEFAULT;
		break;
	default:
		BUG();
	}
	return v9fs_xattr_set(dentry, full_name, value, size, flags);
}


static int v9fs_xattr_set_acl(struct dentry *dentry, const char *name,
			      const void *value, size_t size,
			      int flags, int type)
{
	int retval;
	struct posix_acl *acl;
	struct v9fs_session_info *v9ses;
	struct inode *inode = dentry->d_inode;

	if (strcmp(name, "") != 0)
		return -EINVAL;

	v9ses = v9fs_dentry2v9ses(dentry);
	/*
	 * set the attribute on the remote. Without even looking at the
	 * xattr value. We leave it to the server to validate
	 */
	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
		return v9fs_remote_set_acl(dentry, name,
					   value, size, flags, type);

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;
	if (!inode_owner_or_capable(inode))
		return -EPERM;
	if (value) {
		/* update the cached acl value */
		acl = posix_acl_from_xattr(value, size);
		if (IS_ERR(acl))
			return PTR_ERR(acl);
		else if (acl) {
			retval = posix_acl_valid(acl);
			if (retval)
				goto err_out;
		}
	} else
		acl = NULL;

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = POSIX_ACL_XATTR_ACCESS;
		if (acl) {
			umode_t mode = inode->i_mode;
			retval = posix_acl_equiv_mode(acl, &mode);
			if (retval < 0)
				goto err_out;
			else {
				struct iattr iattr;
				if (retval == 0) {
					/*
					 * ACL can be represented
					 * by the mode bits. So don't
					 * update ACL.
					 */
					acl = NULL;
					value = NULL;
					size = 0;
				}
				/* Updte the mode bits */
				iattr.ia_mode = ((mode & S_IALLUGO) |
						 (inode->i_mode & ~S_IALLUGO));
				iattr.ia_valid = ATTR_MODE;
				/* FIXME should we update ctime ?
				 * What is the following setxattr update the
				 * mode ?
				 */
				v9fs_vfs_setattr_dotl(dentry, &iattr);
			}
		}
		break;
	case ACL_TYPE_DEFAULT:
		name = POSIX_ACL_XATTR_DEFAULT;
		if (!S_ISDIR(inode->i_mode)) {
			retval = acl ? -EINVAL : 0;
			goto err_out;
		}
		break;
	default:
		BUG();
	}
	retval = v9fs_xattr_set(dentry, name, value, size, flags);
	if (!retval)
		set_cached_acl(inode, type, acl);
err_out:
	posix_acl_release(acl);
	return retval;
}

const struct xattr_handler v9fs_xattr_acl_access_handler = {
	.prefix	= POSIX_ACL_XATTR_ACCESS,
	.flags	= ACL_TYPE_ACCESS,
	.get	= v9fs_xattr_get_acl,
	.set	= v9fs_xattr_set_acl,
};

const struct xattr_handler v9fs_xattr_acl_default_handler = {
	.prefix	= POSIX_ACL_XATTR_DEFAULT,
	.flags	= ACL_TYPE_DEFAULT,
	.get	= v9fs_xattr_get_acl,
	.set	= v9fs_xattr_set_acl,
};
Commit	Line	Data
85ff872d AK	1	/*
	2	* Copyright IBM Corporation, 2010
	3	* Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
	4	*
	5	* This program is free software; you can redistribute it and/or modify it
	6	* under the terms of version 2.1 of the GNU Lesser General Public License
	7	* as published by the Free Software Foundation.
	8	*
	9	* This program is distributed in the hope that it would be useful, but
	10	* WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
	12	*
	13	*/
	14
	15	#include <linux/module.h>
	16	#include <linux/fs.h>
	17	#include <net/9p/9p.h>
	18	#include <net/9p/client.h>
	19	#include <linux/slab.h>
22d8dcdf	20	#include <linux/sched.h>
85ff872d AK	21	#include <linux/posix_acl_xattr.h>
	22	#include "xattr.h"
	23	#include "acl.h"
76381a42	24	#include "v9fs.h"
5ffc0cb3	25	#include "v9fs_vfs.h"
85ff872d AK	26
	27	static struct posix_acl __v9fs_get_acl(struct p9_fid fid, char *name)
	28	{
	29	ssize_t size;
	30	void *value = NULL;
009ca389	31	struct posix_acl *acl = NULL;
85ff872d AK	32
	33	size = v9fs_fid_xattr_get(fid, name, NULL, 0);
	34	if (size > 0) {
	35	value = kzalloc(size, GFP_NOFS);
	36	if (!value)
	37	return ERR_PTR(-ENOMEM);
	38	size = v9fs_fid_xattr_get(fid, name, value, size);
	39	if (size > 0) {
	40	acl = posix_acl_from_xattr(value, size);
	41	if (IS_ERR(acl))
	42	goto err_out;
	43	}
	44	} else if (size == -ENODATA \|\| size == 0 \|\|
	45	size == -ENOSYS \|\| size == -EOPNOTSUPP) {
	46	acl = NULL;
	47	} else
	48	acl = ERR_PTR(-EIO);
	49
	50	err_out:
	51	kfree(value);
	52	return acl;
	53	}
	54
	55	int v9fs_get_acl(struct inode inode, struct p9_fid fid)
	56	{
	57	int retval = 0;
	58	struct posix_acl pacl, dacl;
76381a42	59	struct v9fs_session_info *v9ses;
85ff872d	60
76381a42	61	v9ses = v9fs_inode2v9ses(inode);
e782ef71 VJJ	62	if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) \|\|
e782ef71 VJJ	63	((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
76381a42 AK	64	set_cached_acl(inode, ACL_TYPE_DEFAULT, NULL);
	65	set_cached_acl(inode, ACL_TYPE_ACCESS, NULL);
	66	return 0;
	67	}
85ff872d AK	68	/* get the default/access acl values and cache them */
	69	dacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_DEFAULT);
	70	pacl = __v9fs_get_acl(fid, POSIX_ACL_XATTR_ACCESS);
	71
	72	if (!IS_ERR(dacl) && !IS_ERR(pacl)) {
	73	set_cached_acl(inode, ACL_TYPE_DEFAULT, dacl);
	74	set_cached_acl(inode, ACL_TYPE_ACCESS, pacl);
85ff872d AK	75	} else
	76	retval = -EIO;
	77
c61fa0d6 VJJ	78	if (!IS_ERR(dacl))
	79	posix_acl_release(dacl);
	80
	81	if (!IS_ERR(pacl))
	82	posix_acl_release(pacl);
	83
85ff872d AK	84	return retval;
	85	}
	86
	87	static struct posix_acl v9fs_get_cached_acl(struct inode inode, int type)
	88	{
	89	struct posix_acl *acl;
	90	/*
	91	* 9p Always cache the acl value when
	92	* instantiating the inode (v9fs_inode_from_fid)
	93	*/
	94	acl = get_cached_acl(inode, type);
	95	BUG_ON(acl == ACL_NOT_CACHED);
	96	return acl;
	97	}
	98
4e34e719	99	struct posix_acl v9fs_iop_get_acl(struct inode inode, int type)
85ff872d	100	{
76381a42 AK	101	struct v9fs_session_info *v9ses;
	102
	103	v9ses = v9fs_inode2v9ses(inode);
e782ef71 VJJ	104	if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) \|\|
e782ef71 VJJ	105	((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
76381a42	106	/*
e782ef71	107	* On access = client and acl = on mode get the acl
76381a42 AK	108	* values from the server
76381a42 AK	109	*/
4e34e719	110	return NULL;
76381a42	111	}
4e34e719 CH	112	return v9fs_get_cached_acl(inode, type);
4e34e719 CH	113
85ff872d	114	}
7a4566b0	115
6e8dc555 AK	116	static int v9fs_set_acl(struct dentry dentry, int type, struct posix_acl acl)
	117	{
	118	int retval;
	119	char *name;
	120	size_t size;
	121	void *buffer;
	122	struct inode *inode = dentry->d_inode;
	123
	124	set_cached_acl(inode, type, acl);
d344b0fb VJJ	125
	126	if (!acl)
	127	return 0;
	128
6e8dc555 AK	129	/* Set a setxattr request to server */
	130	size = posix_acl_xattr_size(acl->a_count);
	131	buffer = kmalloc(size, GFP_KERNEL);
	132	if (!buffer)
	133	return -ENOMEM;
	134	retval = posix_acl_to_xattr(acl, buffer, size);
	135	if (retval < 0)
	136	goto err_free_out;
	137	switch (type) {
	138	case ACL_TYPE_ACCESS:
	139	name = POSIX_ACL_XATTR_ACCESS;
	140	break;
	141	case ACL_TYPE_DEFAULT:
	142	name = POSIX_ACL_XATTR_DEFAULT;
	143	break;
	144	default:
	145	BUG();
	146	}
	147	retval = v9fs_xattr_set(dentry, name, buffer, size, 0);
	148	err_free_out:
	149	kfree(buffer);
	150	return retval;
	151	}
	152
	153	int v9fs_acl_chmod(struct dentry *dentry)
	154	{
	155	int retval = 0;
bc26ab5f	156	struct posix_acl *acl;
6e8dc555 AK	157	struct inode *inode = dentry->d_inode;
	158
	159	if (S_ISLNK(inode->i_mode))
	160	return -EOPNOTSUPP;
	161	acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);
	162	if (acl) {
bc26ab5f AV	163	retval = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
	164	if (retval)
	165	return retval;
	166	retval = v9fs_set_acl(dentry, ACL_TYPE_ACCESS, acl);
6e8dc555	167	posix_acl_release(acl);
6e8dc555 AK	168	}
	169	return retval;
	170	}
	171
ad77dbce	172	int v9fs_set_create_acl(struct dentry *dentry,
1ec95bf3	173	struct posix_acl dpacl, struct posix_acl pacl)
ad77dbce	174	{
1ec95bf3 AV	175	if (dentry) {
	176	v9fs_set_acl(dentry, ACL_TYPE_DEFAULT, *dpacl);
	177	v9fs_set_acl(dentry, ACL_TYPE_ACCESS, *pacl);
	178	}
	179	posix_acl_release(*dpacl);
	180	posix_acl_release(*pacl);
	181	dpacl = pacl = NULL;
ad77dbce AK	182	return 0;
	183	}
	184
d3fb6120	185	int v9fs_acl_mode(struct inode dir, umode_t modep,
ad77dbce AK	186	struct posix_acl dpacl, struct posix_acl pacl)
	187	{
	188	int retval = 0;
d3fb6120	189	umode_t mode = *modep;
ad77dbce AK	190	struct posix_acl *acl = NULL;
	191
	192	if (!S_ISLNK(mode)) {
	193	acl = v9fs_get_cached_acl(dir, ACL_TYPE_DEFAULT);
	194	if (IS_ERR(acl))
	195	return PTR_ERR(acl);
	196	if (!acl)
	197	mode &= ~current_umask();
	198	}
	199	if (acl) {
ad77dbce	200	if (S_ISDIR(mode))
1ec95bf3	201	*dpacl = posix_acl_dup(acl);
826cae2f AV	202	retval = posix_acl_create(&acl, GFP_NOFS, &mode);
	203	if (retval < 0)
	204	return retval;
ad77dbce	205	if (retval > 0)
826cae2f	206	*pacl = acl;
1ec95bf3	207	else
826cae2f	208	posix_acl_release(acl);
ad77dbce AK	209	}
	210	*modep = mode;
	211	return 0;
ad77dbce AK	212	}
ad77dbce AK	213
76381a42 AK	214	static int v9fs_remote_get_acl(struct dentry dentry, const char name,
	215	void *buffer, size_t size, int type)
	216	{
	217	char *full_name;
	218
	219	switch (type) {
	220	case ACL_TYPE_ACCESS:
	221	full_name = POSIX_ACL_XATTR_ACCESS;
	222	break;
	223	case ACL_TYPE_DEFAULT:
	224	full_name = POSIX_ACL_XATTR_DEFAULT;
	225	break;
	226	default:
	227	BUG();
	228	}
	229	return v9fs_xattr_get(dentry, full_name, buffer, size);
	230	}
	231
7a4566b0 AK	232	static int v9fs_xattr_get_acl(struct dentry dentry, const char name,
	233	void *buffer, size_t size, int type)
	234	{
76381a42	235	struct v9fs_session_info *v9ses;
7a4566b0 AK	236	struct posix_acl *acl;
	237	int error;
	238
	239	if (strcmp(name, "") != 0)
	240	return -EINVAL;
	241
42869c8a	242	v9ses = v9fs_dentry2v9ses(dentry);
76381a42 AK	243	/*
	244	* We allow set/get/list of acl when access=client is not specified
	245	*/
	246	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
	247	return v9fs_remote_get_acl(dentry, name, buffer, size, type);
	248
7a4566b0 AK	249	acl = v9fs_get_cached_acl(dentry->d_inode, type);
	250	if (IS_ERR(acl))
	251	return PTR_ERR(acl);
	252	if (acl == NULL)
	253	return -ENODATA;
	254	error = posix_acl_to_xattr(acl, buffer, size);
	255	posix_acl_release(acl);
	256
	257	return error;
	258	}
	259
76381a42 AK	260	static int v9fs_remote_set_acl(struct dentry dentry, const char name,
	261	const void *value, size_t size,
	262	int flags, int type)
	263	{
	264	char *full_name;
	265
	266	switch (type) {
	267	case ACL_TYPE_ACCESS:
	268	full_name = POSIX_ACL_XATTR_ACCESS;
	269	break;
	270	case ACL_TYPE_DEFAULT:
	271	full_name = POSIX_ACL_XATTR_DEFAULT;
	272	break;
	273	default:
	274	BUG();
	275	}
	276	return v9fs_xattr_set(dentry, full_name, value, size, flags);
	277	}
	278
	279
7a4566b0 AK	280	static int v9fs_xattr_set_acl(struct dentry dentry, const char name,
	281	const void *value, size_t size,
	282	int flags, int type)
	283	{
22d8dcdf AK	284	int retval;
22d8dcdf AK	285	struct posix_acl *acl;
76381a42	286	struct v9fs_session_info *v9ses;
22d8dcdf AK	287	struct inode *inode = dentry->d_inode;
	288
	289	if (strcmp(name, "") != 0)
	290	return -EINVAL;
76381a42	291
42869c8a	292	v9ses = v9fs_dentry2v9ses(dentry);
76381a42 AK	293	/*
	294	* set the attribute on the remote. Without even looking at the
	295	* xattr value. We leave it to the server to validate
	296	*/
	297	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
	298	return v9fs_remote_set_acl(dentry, name,
	299	value, size, flags, type);
	300
22d8dcdf AK	301	if (S_ISLNK(inode->i_mode))
22d8dcdf AK	302	return -EOPNOTSUPP;
2e149670	303	if (!inode_owner_or_capable(inode))
22d8dcdf AK	304	return -EPERM;
	305	if (value) {
	306	/* update the cached acl value */
	307	acl = posix_acl_from_xattr(value, size);
	308	if (IS_ERR(acl))
	309	return PTR_ERR(acl);
	310	else if (acl) {
	311	retval = posix_acl_valid(acl);
	312	if (retval)
	313	goto err_out;
	314	}
	315	} else
	316	acl = NULL;
	317
	318	switch (type) {
	319	case ACL_TYPE_ACCESS:
	320	name = POSIX_ACL_XATTR_ACCESS;
	321	if (acl) {
d6952123	322	umode_t mode = inode->i_mode;
22d8dcdf AK	323	retval = posix_acl_equiv_mode(acl, &mode);
	324	if (retval < 0)
	325	goto err_out;
	326	else {
	327	struct iattr iattr;
	328	if (retval == 0) {
	329	/*
	330	* ACL can be represented
	331	* by the mode bits. So don't
	332	* update ACL.
	333	*/
	334	acl = NULL;
	335	value = NULL;
	336	size = 0;
	337	}
	338	/* Updte the mode bits */
	339	iattr.ia_mode = ((mode & S_IALLUGO) \|
	340	(inode->i_mode & ~S_IALLUGO));
	341	iattr.ia_valid = ATTR_MODE;
	342	/* FIXME should we update ctime ?
	343	* What is the following setxattr update the
	344	* mode ?
	345	*/
	346	v9fs_vfs_setattr_dotl(dentry, &iattr);
	347	}
	348	}
	349	break;
	350	case ACL_TYPE_DEFAULT:
	351	name = POSIX_ACL_XATTR_DEFAULT;
	352	if (!S_ISDIR(inode->i_mode)) {
6f81c115	353	retval = acl ? -EINVAL : 0;
22d8dcdf AK	354	goto err_out;
	355	}
	356	break;
	357	default:
	358	BUG();
	359	}
	360	retval = v9fs_xattr_set(dentry, name, value, size, flags);
	361	if (!retval)
	362	set_cached_acl(inode, type, acl);
	363	err_out:
	364	posix_acl_release(acl);
	365	return retval;
7a4566b0 AK	366	}
	367
	368	const struct xattr_handler v9fs_xattr_acl_access_handler = {
	369	.prefix = POSIX_ACL_XATTR_ACCESS,
	370	.flags = ACL_TYPE_ACCESS,
	371	.get = v9fs_xattr_get_acl,
	372	.set = v9fs_xattr_set_acl,
	373	};
	374
	375	const struct xattr_handler v9fs_xattr_acl_default_handler = {
	376	.prefix = POSIX_ACL_XATTR_DEFAULT,
	377	.flags = ACL_TYPE_DEFAULT,
	378	.get = v9fs_xattr_get_acl,
	379	.set = v9fs_xattr_set_acl,
	380	};