[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);
	else
		forget_cached_acl(inode, type);
	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 = XATTR_NAME_POSIX_ACL_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		name = XATTR_NAME_POSIX_ACL_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;

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = XATTR_NAME_POSIX_ACL_ACCESS;
		if (acl) {
			ret = posix_acl_update_mode(inode, &new_mode, &acl);
			if (ret)
				goto out;
		}
		break;
	case ACL_TYPE_DEFAULT:
		if (!S_ISDIR(inode->i_mode)) {
			ret = acl ? -EINVAL : 0;
			goto out;
		}
		name = XATTR_NAME_POSIX_ACL_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;
	}

	if (ceph_snap(inode) != CEPH_NOSNAP) {
		ret = -EROFS;
		goto out_free;
	}

	if (new_mode != old_mode) {
		newattrs.ia_ctime = current_time(inode);
		newattrs.ia_mode = new_mode;
		newattrs.ia_valid = ATTR_MODE;
		ret = __ceph_setattr(inode, &newattrs);
		if (ret)
			goto out_free;
	}

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

	ceph_set_cached_acl(inode, type, acl);

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_KERNEL);
	if (!tmp_buf)
		goto out_err;
	pagelist = kmalloc(sizeof(struct ceph_pagelist), GFP_KERNEL);
	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(XATTR_NAME_POSIX_ACL_ACCESS);
		err = ceph_pagelist_reserve(pagelist, len + val_size1 + 8);
		if (err)
			goto out_err;
		ceph_pagelist_encode_string(pagelist, XATTR_NAME_POSIX_ACL_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(XATTR_NAME_POSIX_ACL_DEFAULT);
		err = ceph_pagelist_reserve(pagelist, len + val_size2 + 8);
		if (err)
			goto out_err;
		err = ceph_pagelist_encode_string(pagelist,
						  XATTR_NAME_POSIX_ACL_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);
b8a7a3a6 AG	40	else
b8a7a3a6 AG	41	forget_cached_acl(inode, type);
7221fe4c GZ	42	spin_unlock(&ci->i_ceph_lock);
	43	}
	44
7221fe4c GZ	45	struct posix_acl ceph_get_acl(struct inode inode, int type)
	46	{
	47	int size;
	48	const char *name;
	49	char *value = NULL;
	50	struct posix_acl *acl;
	51
7221fe4c GZ	52	switch (type) {
7221fe4c GZ	53	case ACL_TYPE_ACCESS:
97d79299	54	name = XATTR_NAME_POSIX_ACL_ACCESS;
7221fe4c GZ	55	break;
7221fe4c GZ	56	case ACL_TYPE_DEFAULT:
97d79299	57	name = XATTR_NAME_POSIX_ACL_DEFAULT;
7221fe4c GZ	58	break;
	59	default:
	60	BUG();
	61	}
	62
	63	size = __ceph_getxattr(inode, name, "", 0);
	64	if (size > 0) {
	65	value = kzalloc(size, GFP_NOFS);
	66	if (!value)
	67	return ERR_PTR(-ENOMEM);
	68	size = __ceph_getxattr(inode, name, value, size);
	69	}
	70
	71	if (size > 0)
	72	acl = posix_acl_from_xattr(&init_user_ns, value, size);
	73	else if (size == -ERANGE \|\| size == -ENODATA \|\| size == 0)
	74	acl = NULL;
	75	else
	76	acl = ERR_PTR(-EIO);
	77
	78	kfree(value);
	79
	80	if (!IS_ERR(acl))
	81	ceph_set_cached_acl(inode, type, acl);
	82
	83	return acl;
	84	}
	85
72466d0b	86	int ceph_set_acl(struct inode inode, struct posix_acl acl, int type)
7221fe4c GZ	87	{
	88	int ret = 0, size = 0;
	89	const char *name = NULL;
	90	char *value = NULL;
	91	struct iattr newattrs;
	92	umode_t new_mode = inode->i_mode, old_mode = inode->i_mode;
	93
7221fe4c GZ	94	switch (type) {
7221fe4c GZ	95	case ACL_TYPE_ACCESS:
97d79299	96	name = XATTR_NAME_POSIX_ACL_ACCESS;
7221fe4c	97	if (acl) {
07393101 JK	98	ret = posix_acl_update_mode(inode, &new_mode, &acl);
07393101 JK	99	if (ret)
7221fe4c	100	goto out;
7221fe4c GZ	101	}
	102	break;
	103	case ACL_TYPE_DEFAULT:
	104	if (!S_ISDIR(inode->i_mode)) {
	105	ret = acl ? -EINVAL : 0;
	106	goto out;
	107	}
97d79299	108	name = XATTR_NAME_POSIX_ACL_DEFAULT;
7221fe4c GZ	109	break;
	110	default:
	111	ret = -EINVAL;
	112	goto out;
	113	}
	114
	115	if (acl) {
	116	size = posix_acl_xattr_size(acl->a_count);
	117	value = kmalloc(size, GFP_NOFS);
	118	if (!value) {
	119	ret = -ENOMEM;
	120	goto out;
	121	}
	122
	123	ret = posix_acl_to_xattr(&init_user_ns, acl, value, size);
	124	if (ret < 0)
	125	goto out_free;
	126	}
	127
fd5472ed JK	128	if (ceph_snap(inode) != CEPH_NOSNAP) {
	129	ret = -EROFS;
	130	goto out_free;
	131	}
	132
7221fe4c	133	if (new_mode != old_mode) {
4ca2fea6	134	newattrs.ia_ctime = current_time(inode);
7221fe4c GZ	135	newattrs.ia_mode = new_mode;
7221fe4c GZ	136	newattrs.ia_valid = ATTR_MODE;
a26fecca	137	ret = __ceph_setattr(inode, &newattrs);
7221fe4c	138	if (ret)
a26fecca	139	goto out_free;
7221fe4c GZ	140	}
7221fe4c GZ	141
a26fecca	142	ret = __ceph_setxattr(inode, name, value, size, 0);
7221fe4c GZ	143	if (ret) {
	144	if (new_mode != old_mode) {
	145	newattrs.ia_mode = old_mode;
	146	newattrs.ia_valid = ATTR_MODE;
a26fecca	147	__ceph_setattr(inode, &newattrs);
7221fe4c	148	}
a26fecca	149	goto out_free;
7221fe4c GZ	150	}
	151
	152	ceph_set_cached_acl(inode, type, acl);
	153
	154	out_free:
	155	kfree(value);
	156	out:
	157	return ret;
	158	}
	159
b1ee94aa YZ	160	int ceph_pre_init_acls(struct inode dir, umode_t mode,
b1ee94aa YZ	161	struct ceph_acls_info *info)
7221fe4c	162	{
b1ee94aa YZ	163	struct posix_acl acl, default_acl;
	164	size_t val_size1 = 0, val_size2 = 0;
	165	struct ceph_pagelist *pagelist = NULL;
	166	void *tmp_buf = NULL;
	167	int err;
	168
	169	err = posix_acl_create(dir, mode, &default_acl, &acl);
	170	if (err)
	171	return err;
	172
	173	if (acl) {
	174	int ret = posix_acl_equiv_mode(acl, mode);
	175	if (ret < 0)
	176	goto out_err;
	177	if (ret == 0) {
	178	posix_acl_release(acl);
	179	acl = NULL;
f5f18647	180	}
f5f18647	181	}
7221fe4c	182
b1ee94aa YZ	183	if (!default_acl && !acl)
	184	return 0;
	185
	186	if (acl)
	187	val_size1 = posix_acl_xattr_size(acl->a_count);
	188	if (default_acl)
	189	val_size2 = posix_acl_xattr_size(default_acl->a_count);
	190
	191	err = -ENOMEM;
687265e5	192	tmp_buf = kmalloc(max(val_size1, val_size2), GFP_KERNEL);
b1ee94aa YZ	193	if (!tmp_buf)
b1ee94aa YZ	194	goto out_err;
687265e5	195	pagelist = kmalloc(sizeof(struct ceph_pagelist), GFP_KERNEL);
b1ee94aa YZ	196	if (!pagelist)
	197	goto out_err;
	198	ceph_pagelist_init(pagelist);
	199
	200	err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
	201	if (err)
	202	goto out_err;
	203
	204	ceph_pagelist_encode_32(pagelist, acl && default_acl ? 2 : 1);
	205
75858236	206	if (acl) {
97d79299	207	size_t len = strlen(XATTR_NAME_POSIX_ACL_ACCESS);
b1ee94aa YZ	208	err = ceph_pagelist_reserve(pagelist, len + val_size1 + 8);
	209	if (err)
	210	goto out_err;
97d79299	211	ceph_pagelist_encode_string(pagelist, XATTR_NAME_POSIX_ACL_ACCESS,
b1ee94aa YZ	212	len);
	213	err = posix_acl_to_xattr(&init_user_ns, acl,
	214	tmp_buf, val_size1);
	215	if (err < 0)
	216	goto out_err;
	217	ceph_pagelist_encode_32(pagelist, val_size1);
	218	ceph_pagelist_append(pagelist, tmp_buf, val_size1);
75858236	219	}
b1ee94aa	220	if (default_acl) {
97d79299	221	size_t len = strlen(XATTR_NAME_POSIX_ACL_DEFAULT);
b1ee94aa YZ	222	err = ceph_pagelist_reserve(pagelist, len + val_size2 + 8);
	223	if (err)
	224	goto out_err;
	225	err = ceph_pagelist_encode_string(pagelist,
97d79299	226	XATTR_NAME_POSIX_ACL_DEFAULT, len);
b1ee94aa YZ	227	err = posix_acl_to_xattr(&init_user_ns, default_acl,
	228	tmp_buf, val_size2);
	229	if (err < 0)
	230	goto out_err;
	231	ceph_pagelist_encode_32(pagelist, val_size2);
	232	ceph_pagelist_append(pagelist, tmp_buf, val_size2);
	233	}
	234
	235	kfree(tmp_buf);
	236
	237	info->acl = acl;
	238	info->default_acl = default_acl;
	239	info->pagelist = pagelist;
	240	return 0;
	241
	242	out_err:
	243	posix_acl_release(acl);
	244	posix_acl_release(default_acl);
	245	kfree(tmp_buf);
	246	if (pagelist)
	247	ceph_pagelist_release(pagelist);
	248	return err;
	249	}
	250
	251	void ceph_init_inode_acls(struct inode* inode, struct ceph_acls_info *info)
	252	{
	253	if (!inode)
	254	return;
	255	ceph_set_cached_acl(inode, ACL_TYPE_ACCESS, info->acl);
	256	ceph_set_cached_acl(inode, ACL_TYPE_DEFAULT, info->default_acl);
	257	}
	258
	259	void ceph_release_acls_info(struct ceph_acls_info *info)
	260	{
	261	posix_acl_release(info->acl);
	262	posix_acl_release(info->default_acl);
	263	if (info->pagelist)
	264	ceph_pagelist_release(info->pagelist);
7221fe4c	265	}