[linux.git] / fs / ceph / acl.c

/*
 * linux/fs/ceph/acl.c
 *
 * Copyright (C) 2013 Guangliang Zhao, <[email protected]>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License v2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#include <linux/ceph/ceph_debug.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/xattr.h>
#include <linux/posix_acl_xattr.h>
#include <linux/posix_acl.h>
#include <linux/sched.h>
#include <linux/slab.h>

#include "super.h"

static inline void ceph_set_cached_acl(struct inode *inode,
					int type, struct posix_acl *acl)
{
	struct ceph_inode_info *ci = ceph_inode(inode);

	spin_lock(&ci->i_ceph_lock);
	if (__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 0))
		set_cached_acl(inode, type, acl);
	spin_unlock(&ci->i_ceph_lock);
}

struct posix_acl *ceph_get_acl(struct inode *inode, int type)
{
	int size;
	const char *name;
	char *value = NULL;
	struct posix_acl *acl;

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = POSIX_ACL_XATTR_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		name = POSIX_ACL_XATTR_DEFAULT;
		break;
	default:
		BUG();
	}

	size = __ceph_getxattr(inode, name, "", 0);
	if (size > 0) {
		value = kzalloc(size, GFP_NOFS);
		if (!value)
			return ERR_PTR(-ENOMEM);
		size = __ceph_getxattr(inode, name, value, size);
	}

	if (size > 0)
		acl = posix_acl_from_xattr(&init_user_ns, value, size);
	else if (size == -ERANGE || size == -ENODATA || size == 0)
		acl = NULL;
	else
		acl = ERR_PTR(-EIO);

	kfree(value);

	if (!IS_ERR(acl))
		ceph_set_cached_acl(inode, type, acl);

	return acl;
}

int ceph_set_acl(struct inode *inode, struct posix_acl *acl, int type)
{
	int ret = 0, size = 0;
	const char *name = NULL;
	char *value = NULL;
	struct iattr newattrs;
	umode_t new_mode = inode->i_mode, old_mode = inode->i_mode;
	struct dentry *dentry;

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = POSIX_ACL_XATTR_ACCESS;
		if (acl) {
			ret = posix_acl_equiv_mode(acl, &new_mode);
			if (ret < 0)
				goto out;
			if (ret == 0)
				acl = NULL;
		}
		break;
	case ACL_TYPE_DEFAULT:
		if (!S_ISDIR(inode->i_mode)) {
			ret = acl ? -EINVAL : 0;
			goto out;
		}
		name = POSIX_ACL_XATTR_DEFAULT;
		break;
	default:
		ret = -EINVAL;
		goto out;
	}

	if (acl) {
		size = posix_acl_xattr_size(acl->a_count);
		value = kmalloc(size, GFP_NOFS);
		if (!value) {
			ret = -ENOMEM;
			goto out;
		}

		ret = posix_acl_to_xattr(&init_user_ns, acl, value, size);
		if (ret < 0)
			goto out_free;
	}

	dentry = d_find_alias(inode);
	if (new_mode != old_mode) {
		newattrs.ia_mode = new_mode;
		newattrs.ia_valid = ATTR_MODE;
		ret = ceph_setattr(dentry, &newattrs);
		if (ret)
			goto out_dput;
	}

	ret = __ceph_setxattr(dentry, name, value, size, 0);
	if (ret) {
		if (new_mode != old_mode) {
			newattrs.ia_mode = old_mode;
			newattrs.ia_valid = ATTR_MODE;
			ceph_setattr(dentry, &newattrs);
		}
		goto out_dput;
	}

	ceph_set_cached_acl(inode, type, acl);

out_dput:
	dput(dentry);
out_free:
	kfree(value);
out:
	return ret;
}

int ceph_pre_init_acls(struct inode *dir, umode_t *mode,
		       struct ceph_acls_info *info)
{
	struct posix_acl *acl, *default_acl;
	size_t val_size1 = 0, val_size2 = 0;
	struct ceph_pagelist *pagelist = NULL;
	void *tmp_buf = NULL;
	int err;

	err = posix_acl_create(dir, mode, &default_acl, &acl);
	if (err)
		return err;

	if (acl) {
		int ret = posix_acl_equiv_mode(acl, mode);
		if (ret < 0)
			goto out_err;
		if (ret == 0) {
			posix_acl_release(acl);
			acl = NULL;
		}
	}

	if (!default_acl && !acl)
		return 0;

	if (acl)
		val_size1 = posix_acl_xattr_size(acl->a_count);
	if (default_acl)
		val_size2 = posix_acl_xattr_size(default_acl->a_count);

	err = -ENOMEM;
	tmp_buf = kmalloc(max(val_size1, val_size2), GFP_NOFS);
	if (!tmp_buf)
		goto out_err;
	pagelist = kmalloc(sizeof(struct ceph_pagelist), GFP_NOFS);
	if (!pagelist)
		goto out_err;
	ceph_pagelist_init(pagelist);

	err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
	if (err)
		goto out_err;

	ceph_pagelist_encode_32(pagelist, acl && default_acl ? 2 : 1);

	if (acl) {
		size_t len = strlen(POSIX_ACL_XATTR_ACCESS);
		err = ceph_pagelist_reserve(pagelist, len + val_size1 + 8);
		if (err)
			goto out_err;
		ceph_pagelist_encode_string(pagelist, POSIX_ACL_XATTR_ACCESS,
					    len);
		err = posix_acl_to_xattr(&init_user_ns, acl,
					 tmp_buf, val_size1);
		if (err < 0)
			goto out_err;
		ceph_pagelist_encode_32(pagelist, val_size1);
		ceph_pagelist_append(pagelist, tmp_buf, val_size1);
	}
	if (default_acl) {
		size_t len = strlen(POSIX_ACL_XATTR_DEFAULT);
		err = ceph_pagelist_reserve(pagelist, len + val_size2 + 8);
		if (err)
			goto out_err;
		err = ceph_pagelist_encode_string(pagelist,
						  POSIX_ACL_XATTR_DEFAULT, len);
		err = posix_acl_to_xattr(&init_user_ns, default_acl,
					 tmp_buf, val_size2);
		if (err < 0)
			goto out_err;
		ceph_pagelist_encode_32(pagelist, val_size2);
		ceph_pagelist_append(pagelist, tmp_buf, val_size2);
	}

	kfree(tmp_buf);

	info->acl = acl;
	info->default_acl = default_acl;
	info->pagelist = pagelist;
	return 0;

out_err:
	posix_acl_release(acl);
	posix_acl_release(default_acl);
	kfree(tmp_buf);
	if (pagelist)
		ceph_pagelist_release(pagelist);
	return err;
}

void ceph_init_inode_acls(struct inode* inode, struct ceph_acls_info *info)
{
	if (!inode)
		return;
	ceph_set_cached_acl(inode, ACL_TYPE_ACCESS, info->acl);
	ceph_set_cached_acl(inode, ACL_TYPE_DEFAULT, info->default_acl);
}

void ceph_release_acls_info(struct ceph_acls_info *info)
{
	posix_acl_release(info->acl);
	posix_acl_release(info->default_acl);
	if (info->pagelist)
		ceph_pagelist_release(info->pagelist);
}
Commit	Line	Data
7221fe4c GZ	1	/*
	2	* linux/fs/ceph/acl.c
	3	*
	4	* Copyright (C) 2013 Guangliang Zhao, <[email protected]>
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public
	8	* License v2 as published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	* General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public
	16	* License along with this program; if not, write to the
	17	* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	18	* Boston, MA 021110-1307, USA.
	19	*/
	20
	21	#include <linux/ceph/ceph_debug.h>
	22	#include <linux/fs.h>
	23	#include <linux/string.h>
	24	#include <linux/xattr.h>
	25	#include <linux/posix_acl_xattr.h>
	26	#include <linux/posix_acl.h>
	27	#include <linux/sched.h>
	28	#include <linux/slab.h>
	29
	30	#include "super.h"
	31
	32	static inline void ceph_set_cached_acl(struct inode *inode,
	33	int type, struct posix_acl *acl)
	34	{
	35	struct ceph_inode_info *ci = ceph_inode(inode);
	36
	37	spin_lock(&ci->i_ceph_lock);
	38	if (__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 0))
	39	set_cached_acl(inode, type, acl);
	40	spin_unlock(&ci->i_ceph_lock);
	41	}
	42
7221fe4c GZ	43	struct posix_acl ceph_get_acl(struct inode inode, int type)
	44	{
	45	int size;
	46	const char *name;
	47	char *value = NULL;
	48	struct posix_acl *acl;
	49
7221fe4c GZ	50	switch (type) {
	51	case ACL_TYPE_ACCESS:
	52	name = POSIX_ACL_XATTR_ACCESS;
	53	break;
	54	case ACL_TYPE_DEFAULT:
	55	name = POSIX_ACL_XATTR_DEFAULT;
	56	break;
	57	default:
	58	BUG();
	59	}
	60
	61	size = __ceph_getxattr(inode, name, "", 0);
	62	if (size > 0) {
	63	value = kzalloc(size, GFP_NOFS);
	64	if (!value)
	65	return ERR_PTR(-ENOMEM);
	66	size = __ceph_getxattr(inode, name, value, size);
	67	}
	68
	69	if (size > 0)
	70	acl = posix_acl_from_xattr(&init_user_ns, value, size);
	71	else if (size == -ERANGE \|\| size == -ENODATA \|\| size == 0)
	72	acl = NULL;
	73	else
	74	acl = ERR_PTR(-EIO);
	75
	76	kfree(value);
	77
	78	if (!IS_ERR(acl))
	79	ceph_set_cached_acl(inode, type, acl);
	80
	81	return acl;
	82	}
	83
72466d0b	84	int ceph_set_acl(struct inode inode, struct posix_acl acl, int type)
7221fe4c GZ	85	{
	86	int ret = 0, size = 0;
	87	const char *name = NULL;
	88	char *value = NULL;
	89	struct iattr newattrs;
	90	umode_t new_mode = inode->i_mode, old_mode = inode->i_mode;
77516dc9	91	struct dentry *dentry;
7221fe4c	92
7221fe4c GZ	93	switch (type) {
	94	case ACL_TYPE_ACCESS:
	95	name = POSIX_ACL_XATTR_ACCESS;
	96	if (acl) {
	97	ret = posix_acl_equiv_mode(acl, &new_mode);
	98	if (ret < 0)
	99	goto out;
	100	if (ret == 0)
	101	acl = NULL;
	102	}
	103	break;
	104	case ACL_TYPE_DEFAULT:
	105	if (!S_ISDIR(inode->i_mode)) {
	106	ret = acl ? -EINVAL : 0;
	107	goto out;
	108	}
	109	name = POSIX_ACL_XATTR_DEFAULT;
	110	break;
	111	default:
	112	ret = -EINVAL;
	113	goto out;
	114	}
	115
	116	if (acl) {
	117	size = posix_acl_xattr_size(acl->a_count);
	118	value = kmalloc(size, GFP_NOFS);
	119	if (!value) {
	120	ret = -ENOMEM;
	121	goto out;
	122	}
	123
	124	ret = posix_acl_to_xattr(&init_user_ns, acl, value, size);
	125	if (ret < 0)
	126	goto out_free;
	127	}
	128
77516dc9	129	dentry = d_find_alias(inode);
7221fe4c GZ	130	if (new_mode != old_mode) {
	131	newattrs.ia_mode = new_mode;
	132	newattrs.ia_valid = ATTR_MODE;
	133	ret = ceph_setattr(dentry, &newattrs);
	134	if (ret)
77516dc9	135	goto out_dput;
7221fe4c GZ	136	}
7221fe4c GZ	137
7a92d647	138	ret = __ceph_setxattr(dentry, name, value, size, 0);
7221fe4c GZ	139	if (ret) {
	140	if (new_mode != old_mode) {
	141	newattrs.ia_mode = old_mode;
	142	newattrs.ia_valid = ATTR_MODE;
	143	ceph_setattr(dentry, &newattrs);
	144	}
77516dc9	145	goto out_dput;
7221fe4c GZ	146	}
	147
	148	ceph_set_cached_acl(inode, type, acl);
	149
77516dc9 SW	150	out_dput:
77516dc9 SW	151	dput(dentry);
7221fe4c GZ	152	out_free:
	153	kfree(value);
	154	out:
	155	return ret;
	156	}
	157
b1ee94aa YZ	158	int ceph_pre_init_acls(struct inode dir, umode_t mode,
b1ee94aa YZ	159	struct ceph_acls_info *info)
7221fe4c	160	{
b1ee94aa YZ	161	struct posix_acl acl, default_acl;
	162	size_t val_size1 = 0, val_size2 = 0;
	163	struct ceph_pagelist *pagelist = NULL;
	164	void *tmp_buf = NULL;
	165	int err;
	166
	167	err = posix_acl_create(dir, mode, &default_acl, &acl);
	168	if (err)
	169	return err;
	170
	171	if (acl) {
	172	int ret = posix_acl_equiv_mode(acl, mode);
	173	if (ret < 0)
	174	goto out_err;
	175	if (ret == 0) {
	176	posix_acl_release(acl);
	177	acl = NULL;
f5f18647	178	}
f5f18647	179	}
7221fe4c	180
b1ee94aa YZ	181	if (!default_acl && !acl)
	182	return 0;
	183
	184	if (acl)
	185	val_size1 = posix_acl_xattr_size(acl->a_count);
	186	if (default_acl)
	187	val_size2 = posix_acl_xattr_size(default_acl->a_count);
	188
	189	err = -ENOMEM;
	190	tmp_buf = kmalloc(max(val_size1, val_size2), GFP_NOFS);
	191	if (!tmp_buf)
	192	goto out_err;
	193	pagelist = kmalloc(sizeof(struct ceph_pagelist), GFP_NOFS);
	194	if (!pagelist)
	195	goto out_err;
	196	ceph_pagelist_init(pagelist);
	197
	198	err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
	199	if (err)
	200	goto out_err;
	201
	202	ceph_pagelist_encode_32(pagelist, acl && default_acl ? 2 : 1);
	203
75858236	204	if (acl) {
b1ee94aa YZ	205	size_t len = strlen(POSIX_ACL_XATTR_ACCESS);
	206	err = ceph_pagelist_reserve(pagelist, len + val_size1 + 8);
	207	if (err)
	208	goto out_err;
	209	ceph_pagelist_encode_string(pagelist, POSIX_ACL_XATTR_ACCESS,
	210	len);
	211	err = posix_acl_to_xattr(&init_user_ns, acl,
	212	tmp_buf, val_size1);
	213	if (err < 0)
	214	goto out_err;
	215	ceph_pagelist_encode_32(pagelist, val_size1);
	216	ceph_pagelist_append(pagelist, tmp_buf, val_size1);
75858236	217	}
b1ee94aa YZ	218	if (default_acl) {
	219	size_t len = strlen(POSIX_ACL_XATTR_DEFAULT);
	220	err = ceph_pagelist_reserve(pagelist, len + val_size2 + 8);
	221	if (err)
	222	goto out_err;
	223	err = ceph_pagelist_encode_string(pagelist,
	224	POSIX_ACL_XATTR_DEFAULT, len);
	225	err = posix_acl_to_xattr(&init_user_ns, default_acl,
	226	tmp_buf, val_size2);
	227	if (err < 0)
	228	goto out_err;
	229	ceph_pagelist_encode_32(pagelist, val_size2);
	230	ceph_pagelist_append(pagelist, tmp_buf, val_size2);
	231	}
	232
	233	kfree(tmp_buf);
	234
	235	info->acl = acl;
	236	info->default_acl = default_acl;
	237	info->pagelist = pagelist;
	238	return 0;
	239
	240	out_err:
	241	posix_acl_release(acl);
	242	posix_acl_release(default_acl);
	243	kfree(tmp_buf);
	244	if (pagelist)
	245	ceph_pagelist_release(pagelist);
	246	return err;
	247	}
	248
	249	void ceph_init_inode_acls(struct inode* inode, struct ceph_acls_info *info)
	250	{
	251	if (!inode)
	252	return;
	253	ceph_set_cached_acl(inode, ACL_TYPE_ACCESS, info->acl);
	254	ceph_set_cached_acl(inode, ACL_TYPE_DEFAULT, info->default_acl);
	255	}
	256
	257	void ceph_release_acls_info(struct ceph_acls_info *info)
	258	{
	259	posix_acl_release(info->acl);
	260	posix_acl_release(info->default_acl);
	261	if (info->pagelist)
	262	ceph_pagelist_release(info->pagelist);
7221fe4c	263	}