[linux-2.6-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(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;
}

int v9fs_check_acl(struct inode *inode, int mask)
{
	struct posix_acl *acl;
	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 -EAGAIN;
	}
	acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);

	if (IS_ERR(acl))
		return PTR_ERR(acl);
	if (acl) {
		int error = posix_acl_permission(inode, acl, mask);
		posix_acl_release(acl);
		return error;
	}
	return -EAGAIN;
}

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, *clone;
	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) {
		clone = posix_acl_clone(acl, GFP_KERNEL);
		posix_acl_release(acl);
		if (!clone)
			return -ENOMEM;
		retval = posix_acl_chmod_masq(clone, inode->i_mode);
		if (!retval)
			retval = v9fs_set_acl(dentry, ACL_TYPE_ACCESS, clone);
		posix_acl_release(clone);
	}
	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, mode_t *modep,
		  struct posix_acl **dpacl, struct posix_acl **pacl)
{
	int retval = 0;
	mode_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) {
		struct posix_acl *clone;

		if (S_ISDIR(mode))
			*dpacl = posix_acl_dup(acl);
		clone = posix_acl_clone(acl, GFP_NOFS);
		posix_acl_release(acl);
		if (!clone)
			return -ENOMEM;

		retval = posix_acl_create_masq(clone, &mode);
		if (retval < 0) {
			posix_acl_release(clone);
			goto cleanup;
		}
		if (retval > 0)
			*pacl = clone;
		else
			posix_acl_release(clone);
	}
	*modep  = mode;
	return 0;
cleanup:
	return retval;

}

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) {
			mode_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
7e40145e	99	int v9fs_check_acl(struct inode *inode, int mask)
85ff872d	100	{
76381a42 AK	101	struct posix_acl *acl;
	102	struct v9fs_session_info *v9ses;
	103
	104	v9ses = v9fs_inode2v9ses(inode);
e782ef71 VJJ	105	if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) \|\|
e782ef71 VJJ	106	((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
76381a42	107	/*
e782ef71	108	* On access = client and acl = on mode get the acl
76381a42 AK	109	* values from the server
76381a42 AK	110	*/
ebbb0ef2	111	return -EAGAIN;
76381a42 AK	112	}
76381a42 AK	113	acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);
85ff872d AK	114
	115	if (IS_ERR(acl))
	116	return PTR_ERR(acl);
	117	if (acl) {
	118	int error = posix_acl_permission(inode, acl, mask);
	119	posix_acl_release(acl);
	120	return error;
	121	}
	122	return -EAGAIN;
	123	}
7a4566b0	124
6e8dc555 AK	125	static int v9fs_set_acl(struct dentry dentry, int type, struct posix_acl acl)
	126	{
	127	int retval;
	128	char *name;
	129	size_t size;
	130	void *buffer;
	131	struct inode *inode = dentry->d_inode;
	132
	133	set_cached_acl(inode, type, acl);
d344b0fb VJJ	134
	135	if (!acl)
	136	return 0;
	137
6e8dc555 AK	138	/* Set a setxattr request to server */
	139	size = posix_acl_xattr_size(acl->a_count);
	140	buffer = kmalloc(size, GFP_KERNEL);
	141	if (!buffer)
	142	return -ENOMEM;
	143	retval = posix_acl_to_xattr(acl, buffer, size);
	144	if (retval < 0)
	145	goto err_free_out;
	146	switch (type) {
	147	case ACL_TYPE_ACCESS:
	148	name = POSIX_ACL_XATTR_ACCESS;
	149	break;
	150	case ACL_TYPE_DEFAULT:
	151	name = POSIX_ACL_XATTR_DEFAULT;
	152	break;
	153	default:
	154	BUG();
	155	}
	156	retval = v9fs_xattr_set(dentry, name, buffer, size, 0);
	157	err_free_out:
	158	kfree(buffer);
	159	return retval;
	160	}
	161
	162	int v9fs_acl_chmod(struct dentry *dentry)
	163	{
	164	int retval = 0;
	165	struct posix_acl acl, clone;
	166	struct inode *inode = dentry->d_inode;
	167
	168	if (S_ISLNK(inode->i_mode))
	169	return -EOPNOTSUPP;
	170	acl = v9fs_get_cached_acl(inode, ACL_TYPE_ACCESS);
	171	if (acl) {
	172	clone = posix_acl_clone(acl, GFP_KERNEL);
	173	posix_acl_release(acl);
	174	if (!clone)
	175	return -ENOMEM;
	176	retval = posix_acl_chmod_masq(clone, inode->i_mode);
	177	if (!retval)
	178	retval = v9fs_set_acl(dentry, ACL_TYPE_ACCESS, clone);
	179	posix_acl_release(clone);
	180	}
	181	return retval;
	182	}
	183
ad77dbce	184	int v9fs_set_create_acl(struct dentry *dentry,
1ec95bf3	185	struct posix_acl dpacl, struct posix_acl pacl)
ad77dbce	186	{
1ec95bf3 AV	187	if (dentry) {
	188	v9fs_set_acl(dentry, ACL_TYPE_DEFAULT, *dpacl);
	189	v9fs_set_acl(dentry, ACL_TYPE_ACCESS, *pacl);
	190	}
	191	posix_acl_release(*dpacl);
	192	posix_acl_release(*pacl);
	193	dpacl = pacl = NULL;
ad77dbce AK	194	return 0;
	195	}
	196
	197	int v9fs_acl_mode(struct inode dir, mode_t modep,
	198	struct posix_acl dpacl, struct posix_acl pacl)
	199	{
	200	int retval = 0;
	201	mode_t mode = *modep;
	202	struct posix_acl *acl = NULL;
	203
	204	if (!S_ISLNK(mode)) {
	205	acl = v9fs_get_cached_acl(dir, ACL_TYPE_DEFAULT);
	206	if (IS_ERR(acl))
	207	return PTR_ERR(acl);
	208	if (!acl)
	209	mode &= ~current_umask();
	210	}
	211	if (acl) {
	212	struct posix_acl *clone;
	213
	214	if (S_ISDIR(mode))
1ec95bf3	215	*dpacl = posix_acl_dup(acl);
ad77dbce	216	clone = posix_acl_clone(acl, GFP_NOFS);
1ec95bf3	217	posix_acl_release(acl);
ad77dbce	218	if (!clone)
1ec95bf3	219	return -ENOMEM;
ad77dbce AK	220
	221	retval = posix_acl_create_masq(clone, &mode);
	222	if (retval < 0) {
	223	posix_acl_release(clone);
	224	goto cleanup;
	225	}
	226	if (retval > 0)
	227	*pacl = clone;
1ec95bf3 AV	228	else
1ec95bf3 AV	229	posix_acl_release(clone);
ad77dbce AK	230	}
	231	*modep = mode;
	232	return 0;
	233	cleanup:
ad77dbce AK	234	return retval;
	235
	236	}
	237
76381a42 AK	238	static int v9fs_remote_get_acl(struct dentry dentry, const char name,
	239	void *buffer, size_t size, int type)
	240	{
	241	char *full_name;
	242
	243	switch (type) {
	244	case ACL_TYPE_ACCESS:
	245	full_name = POSIX_ACL_XATTR_ACCESS;
	246	break;
	247	case ACL_TYPE_DEFAULT:
	248	full_name = POSIX_ACL_XATTR_DEFAULT;
	249	break;
	250	default:
	251	BUG();
	252	}
	253	return v9fs_xattr_get(dentry, full_name, buffer, size);
	254	}
	255
7a4566b0 AK	256	static int v9fs_xattr_get_acl(struct dentry dentry, const char name,
	257	void *buffer, size_t size, int type)
	258	{
76381a42	259	struct v9fs_session_info *v9ses;
7a4566b0 AK	260	struct posix_acl *acl;
	261	int error;
	262
	263	if (strcmp(name, "") != 0)
	264	return -EINVAL;
	265
42869c8a	266	v9ses = v9fs_dentry2v9ses(dentry);
76381a42 AK	267	/*
	268	* We allow set/get/list of acl when access=client is not specified
	269	*/
	270	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
	271	return v9fs_remote_get_acl(dentry, name, buffer, size, type);
	272
7a4566b0 AK	273	acl = v9fs_get_cached_acl(dentry->d_inode, type);
	274	if (IS_ERR(acl))
	275	return PTR_ERR(acl);
	276	if (acl == NULL)
	277	return -ENODATA;
	278	error = posix_acl_to_xattr(acl, buffer, size);
	279	posix_acl_release(acl);
	280
	281	return error;
	282	}
	283
76381a42 AK	284	static int v9fs_remote_set_acl(struct dentry dentry, const char name,
	285	const void *value, size_t size,
	286	int flags, int type)
	287	{
	288	char *full_name;
	289
	290	switch (type) {
	291	case ACL_TYPE_ACCESS:
	292	full_name = POSIX_ACL_XATTR_ACCESS;
	293	break;
	294	case ACL_TYPE_DEFAULT:
	295	full_name = POSIX_ACL_XATTR_DEFAULT;
	296	break;
	297	default:
	298	BUG();
	299	}
	300	return v9fs_xattr_set(dentry, full_name, value, size, flags);
	301	}
	302
	303
7a4566b0 AK	304	static int v9fs_xattr_set_acl(struct dentry dentry, const char name,
	305	const void *value, size_t size,
	306	int flags, int type)
	307	{
22d8dcdf AK	308	int retval;
22d8dcdf AK	309	struct posix_acl *acl;
76381a42	310	struct v9fs_session_info *v9ses;
22d8dcdf AK	311	struct inode *inode = dentry->d_inode;
	312
	313	if (strcmp(name, "") != 0)
	314	return -EINVAL;
76381a42	315
42869c8a	316	v9ses = v9fs_dentry2v9ses(dentry);
76381a42 AK	317	/*
	318	* set the attribute on the remote. Without even looking at the
	319	* xattr value. We leave it to the server to validate
	320	*/
	321	if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT)
	322	return v9fs_remote_set_acl(dentry, name,
	323	value, size, flags, type);
	324
22d8dcdf AK	325	if (S_ISLNK(inode->i_mode))
22d8dcdf AK	326	return -EOPNOTSUPP;
2e149670	327	if (!inode_owner_or_capable(inode))
22d8dcdf AK	328	return -EPERM;
	329	if (value) {
	330	/* update the cached acl value */
	331	acl = posix_acl_from_xattr(value, size);
	332	if (IS_ERR(acl))
	333	return PTR_ERR(acl);
	334	else if (acl) {
	335	retval = posix_acl_valid(acl);
	336	if (retval)
	337	goto err_out;
	338	}
	339	} else
	340	acl = NULL;
	341
	342	switch (type) {
	343	case ACL_TYPE_ACCESS:
	344	name = POSIX_ACL_XATTR_ACCESS;
	345	if (acl) {
	346	mode_t mode = inode->i_mode;
	347	retval = posix_acl_equiv_mode(acl, &mode);
	348	if (retval < 0)
	349	goto err_out;
	350	else {
	351	struct iattr iattr;
	352	if (retval == 0) {
	353	/*
	354	* ACL can be represented
	355	* by the mode bits. So don't
	356	* update ACL.
	357	*/
	358	acl = NULL;
	359	value = NULL;
	360	size = 0;
	361	}
	362	/* Updte the mode bits */
	363	iattr.ia_mode = ((mode & S_IALLUGO) \|
	364	(inode->i_mode & ~S_IALLUGO));
	365	iattr.ia_valid = ATTR_MODE;
	366	/* FIXME should we update ctime ?
	367	* What is the following setxattr update the
	368	* mode ?
	369	*/
	370	v9fs_vfs_setattr_dotl(dentry, &iattr);
	371	}
	372	}
	373	break;
	374	case ACL_TYPE_DEFAULT:
	375	name = POSIX_ACL_XATTR_DEFAULT;
	376	if (!S_ISDIR(inode->i_mode)) {
6f81c115	377	retval = acl ? -EINVAL : 0;
22d8dcdf AK	378	goto err_out;
	379	}
	380	break;
	381	default:
	382	BUG();
	383	}
	384	retval = v9fs_xattr_set(dentry, name, value, size, flags);
	385	if (!retval)
	386	set_cached_acl(inode, type, acl);
	387	err_out:
	388	posix_acl_release(acl);
	389	return retval;
7a4566b0 AK	390	}
	391
	392	const struct xattr_handler v9fs_xattr_acl_access_handler = {
	393	.prefix = POSIX_ACL_XATTR_ACCESS,
	394	.flags = ACL_TYPE_ACCESS,
	395	.get = v9fs_xattr_get_acl,
	396	.set = v9fs_xattr_set_acl,
	397	};
	398
	399	const struct xattr_handler v9fs_xattr_acl_default_handler = {
	400	.prefix = POSIX_ACL_XATTR_DEFAULT,
	401	.flags = ACL_TYPE_DEFAULT,
	402	.get = v9fs_xattr_get_acl,
	403	.set = v9fs_xattr_set_acl,
	404	};