[linux-block.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(&init_user_ns, 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;
	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(&init_user_ns, 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;
		set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
		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) {
		set_cached_acl(dentry->d_inode, ACL_TYPE_DEFAULT, *dpacl);
		v9fs_set_acl(dentry, ACL_TYPE_DEFAULT, *dpacl);
		set_cached_acl(dentry->d_inode, ACL_TYPE_ACCESS, *pacl);
		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(&init_user_ns, 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(&init_user_ns, 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) {
5f3a4a28	40	acl = posix_acl_from_xattr(&init_user_ns, value, size);
85ff872d AK	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;
d344b0fb VJJ	122	if (!acl)
	123	return 0;
	124
6e8dc555 AK	125	/* Set a setxattr request to server */
	126	size = posix_acl_xattr_size(acl->a_count);
	127	buffer = kmalloc(size, GFP_KERNEL);
	128	if (!buffer)
	129	return -ENOMEM;
5f3a4a28	130	retval = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
6e8dc555 AK	131	if (retval < 0)
	132	goto err_free_out;
	133	switch (type) {
	134	case ACL_TYPE_ACCESS:
	135	name = POSIX_ACL_XATTR_ACCESS;
	136	break;
	137	case ACL_TYPE_DEFAULT:
	138	name = POSIX_ACL_XATTR_DEFAULT;
	139	break;
	140	default:
	141	BUG();
	142	}
	143	retval = v9fs_xattr_set(dentry, name, buffer, size, 0);
	144	err_free_out:
	145	kfree(buffer);
	146	return retval;
	147	}
	148
	149	int v9fs_acl_chmod(struct dentry *dentry)
	150	{
	151	int retval = 0;
bc26ab5f	152	struct posix_acl *acl;
6e8dc555 AK	153	struct inode *inode = dentry->d_inode;
	154
	155	if (S_ISLNK(inode->i_mode))
	156	return -EOPNOTSUPP;
	157	acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);
	158	if (acl) {
bc26ab5f AV	159	retval = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
	160	if (retval)
	161	return retval;
7f165aaa	162	set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
bc26ab5f	163	retval = v9fs_set_acl(dentry, ACL_TYPE_ACCESS, acl);
6e8dc555	164	posix_acl_release(acl);
6e8dc555 AK	165	}
	166	return retval;
	167	}
	168
ad77dbce	169	int v9fs_set_create_acl(struct dentry *dentry,
1ec95bf3	170	struct posix_acl dpacl, struct posix_acl pacl)
ad77dbce	171	{
1ec95bf3	172	if (dentry) {
7f165aaa	173	set_cached_acl(dentry->d_inode, ACL_TYPE_DEFAULT, *dpacl);
1ec95bf3	174	v9fs_set_acl(dentry, ACL_TYPE_DEFAULT, *dpacl);
7f165aaa	175	set_cached_acl(dentry->d_inode, ACL_TYPE_ACCESS, *pacl);
1ec95bf3 AV	176	v9fs_set_acl(dentry, ACL_TYPE_ACCESS, *pacl);
	177	}
	178	posix_acl_release(*dpacl);
	179	posix_acl_release(*pacl);
	180	dpacl = pacl = NULL;
ad77dbce AK	181	return 0;
	182	}
	183
d3fb6120	184	int v9fs_acl_mode(struct inode dir, umode_t modep,
ad77dbce AK	185	struct posix_acl dpacl, struct posix_acl pacl)
	186	{
	187	int retval = 0;
d3fb6120	188	umode_t mode = *modep;
ad77dbce AK	189	struct posix_acl *acl = NULL;
	190
	191	if (!S_ISLNK(mode)) {
	192	acl = v9fs_get_cached_acl(dir, ACL_TYPE_DEFAULT);
	193	if (IS_ERR(acl))
	194	return PTR_ERR(acl);
	195	if (!acl)
	196	mode &= ~current_umask();
	197	}
	198	if (acl) {
ad77dbce	199	if (S_ISDIR(mode))
1ec95bf3	200	*dpacl = posix_acl_dup(acl);
826cae2f AV	201	retval = posix_acl_create(&acl, GFP_NOFS, &mode);
	202	if (retval < 0)
	203	return retval;
ad77dbce	204	if (retval > 0)
826cae2f	205	*pacl = acl;
1ec95bf3	206	else
826cae2f	207	posix_acl_release(acl);
ad77dbce AK	208	}
	209	*modep = mode;
	210	return 0;
ad77dbce AK	211	}
ad77dbce AK	212
76381a42 AK	213	static int v9fs_remote_get_acl(struct dentry dentry, const char name,
	214	void *buffer, size_t size, int type)
	215	{
	216	char *full_name;
	217
	218	switch (type) {
	219	case ACL_TYPE_ACCESS:
	220	full_name = POSIX_ACL_XATTR_ACCESS;
	221	break;
	222	case ACL_TYPE_DEFAULT:
	223	full_name = POSIX_ACL_XATTR_DEFAULT;
	224	break;
	225	default:
	226	BUG();
	227	}
	228	return v9fs_xattr_get(dentry, full_name, buffer, size);
	229	}
	230
7a4566b0 AK	231	static int v9fs_xattr_get_acl(struct dentry dentry, const char name,
	232	void *buffer, size_t size, int type)
	233	{
76381a42	234	struct v9fs_session_info *v9ses;
7a4566b0 AK	235	struct posix_acl *acl;
	236	int error;
	237
	238	if (strcmp(name, "") != 0)
	239	return -EINVAL;
	240
42869c8a	241	v9ses = v9fs_dentry2v9ses(dentry);
76381a42 AK	242	/*
	243	* We allow set/get/list of acl when access=client is not specified
	244	*/
	245	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
	246	return v9fs_remote_get_acl(dentry, name, buffer, size, type);
	247
7a4566b0 AK	248	acl = v9fs_get_cached_acl(dentry->d_inode, type);
	249	if (IS_ERR(acl))
	250	return PTR_ERR(acl);
	251	if (acl == NULL)
	252	return -ENODATA;
5f3a4a28	253	error = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
7a4566b0 AK	254	posix_acl_release(acl);
	255
	256	return error;
	257	}
	258
76381a42 AK	259	static int v9fs_remote_set_acl(struct dentry dentry, const char name,
	260	const void *value, size_t size,
	261	int flags, int type)
	262	{
	263	char *full_name;
	264
	265	switch (type) {
	266	case ACL_TYPE_ACCESS:
	267	full_name = POSIX_ACL_XATTR_ACCESS;
	268	break;
	269	case ACL_TYPE_DEFAULT:
	270	full_name = POSIX_ACL_XATTR_DEFAULT;
	271	break;
	272	default:
	273	BUG();
	274	}
	275	return v9fs_xattr_set(dentry, full_name, value, size, flags);
	276	}
	277
	278
7a4566b0 AK	279	static int v9fs_xattr_set_acl(struct dentry dentry, const char name,
	280	const void *value, size_t size,
	281	int flags, int type)
	282	{
22d8dcdf AK	283	int retval;
22d8dcdf AK	284	struct posix_acl *acl;
76381a42	285	struct v9fs_session_info *v9ses;
22d8dcdf AK	286	struct inode *inode = dentry->d_inode;
	287
	288	if (strcmp(name, "") != 0)
	289	return -EINVAL;
76381a42	290
42869c8a	291	v9ses = v9fs_dentry2v9ses(dentry);
76381a42 AK	292	/*
	293	* set the attribute on the remote. Without even looking at the
	294	* xattr value. We leave it to the server to validate
	295	*/
	296	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
	297	return v9fs_remote_set_acl(dentry, name,
	298	value, size, flags, type);
	299
22d8dcdf AK	300	if (S_ISLNK(inode->i_mode))
22d8dcdf AK	301	return -EOPNOTSUPP;
2e149670	302	if (!inode_owner_or_capable(inode))
22d8dcdf AK	303	return -EPERM;
	304	if (value) {
	305	/* update the cached acl value */
5f3a4a28	306	acl = posix_acl_from_xattr(&init_user_ns, value, size);
22d8dcdf AK	307	if (IS_ERR(acl))
	308	return PTR_ERR(acl);
	309	else if (acl) {
	310	retval = posix_acl_valid(acl);
	311	if (retval)
	312	goto err_out;
	313	}
	314	} else
	315	acl = NULL;
	316
	317	switch (type) {
	318	case ACL_TYPE_ACCESS:
	319	name = POSIX_ACL_XATTR_ACCESS;
	320	if (acl) {
d6952123	321	umode_t mode = inode->i_mode;
22d8dcdf AK	322	retval = posix_acl_equiv_mode(acl, &mode);
	323	if (retval < 0)
	324	goto err_out;
	325	else {
	326	struct iattr iattr;
	327	if (retval == 0) {
	328	/*
	329	* ACL can be represented
	330	* by the mode bits. So don't
	331	* update ACL.
	332	*/
	333	acl = NULL;
	334	value = NULL;
	335	size = 0;
	336	}
	337	/* Updte the mode bits */
	338	iattr.ia_mode = ((mode & S_IALLUGO) \|
	339	(inode->i_mode & ~S_IALLUGO));
	340	iattr.ia_valid = ATTR_MODE;
	341	/* FIXME should we update ctime ?
	342	* What is the following setxattr update the
	343	* mode ?
	344	*/
	345	v9fs_vfs_setattr_dotl(dentry, &iattr);
	346	}
	347	}
	348	break;
	349	case ACL_TYPE_DEFAULT:
	350	name = POSIX_ACL_XATTR_DEFAULT;
	351	if (!S_ISDIR(inode->i_mode)) {
6f81c115	352	retval = acl ? -EINVAL : 0;
22d8dcdf AK	353	goto err_out;
	354	}
	355	break;
	356	default:
	357	BUG();
	358	}
	359	retval = v9fs_xattr_set(dentry, name, value, size, flags);
	360	if (!retval)
	361	set_cached_acl(inode, type, acl);
	362	err_out:
	363	posix_acl_release(acl);
	364	return retval;
7a4566b0 AK	365	}
	366
	367	const struct xattr_handler v9fs_xattr_acl_access_handler = {
	368	.prefix = POSIX_ACL_XATTR_ACCESS,
	369	.flags = ACL_TYPE_ACCESS,
	370	.get = v9fs_xattr_get_acl,
	371	.set = v9fs_xattr_set_acl,
	372	};
	373
	374	const struct xattr_handler v9fs_xattr_acl_default_handler = {
	375	.prefix = POSIX_ACL_XATTR_DEFAULT,
	376	.flags = ACL_TYPE_DEFAULT,
	377	.get = v9fs_xattr_get_acl,
	378	.set = v9fs_xattr_set_acl,
	379	};