[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;
	unsigned int retry_cnt = 0;
	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();
	}

retry:
	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 == -ERANGE && retry_cnt < 10) {
		retry_cnt++;
		kfree(value);
		value = NULL;
		goto retry;
	}

	if (size > 0) {
		acl = posix_acl_from_xattr(&init_user_ns, value, size);
	} else if (size == -ENODATA || size == 0) {
		acl = NULL;
	} else {
		pr_err_ratelimited("get acl %llx.%llx failed, err=%d\n",
				   ceph_vinop(inode), size);
		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;
	struct timespec64 old_ctime = inode->i_ctime;
	umode_t new_mode = inode->i_mode, old_mode = inode->i_mode;

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

	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 (new_mode != old_mode) {
		newattrs.ia_ctime = current_time(inode);
		newattrs.ia_mode = new_mode;
		newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
		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_ctime = old_ctime;
			newattrs.ia_mode = old_mode;
			newattrs.ia_valid = ATTR_MODE | ATTR_CTIME;
			__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) {
		err = posix_acl_equiv_mode(acl, mode);
		if (err < 0)
			goto out_err;
		if (err == 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 = ceph_pagelist_alloc(GFP_KERNEL);
	if (!pagelist)
		goto out_err;

	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;
f017754d	48	unsigned int retry_cnt = 0;
7221fe4c GZ	49	const char *name;
	50	char *value = NULL;
	51	struct posix_acl *acl;
	52
7221fe4c GZ	53	switch (type) {
7221fe4c GZ	54	case ACL_TYPE_ACCESS:
97d79299	55	name = XATTR_NAME_POSIX_ACL_ACCESS;
7221fe4c GZ	56	break;
7221fe4c GZ	57	case ACL_TYPE_DEFAULT:
97d79299	58	name = XATTR_NAME_POSIX_ACL_DEFAULT;
7221fe4c GZ	59	break;
	60	default:
	61	BUG();
	62	}
	63
f017754d	64	retry:
7221fe4c GZ	65	size = __ceph_getxattr(inode, name, "", 0);
	66	if (size > 0) {
	67	value = kzalloc(size, GFP_NOFS);
	68	if (!value)
	69	return ERR_PTR(-ENOMEM);
	70	size = __ceph_getxattr(inode, name, value, size);
	71	}
	72
f017754d CX	73	if (size == -ERANGE && retry_cnt < 10) {
	74	retry_cnt++;
	75	kfree(value);
	76	value = NULL;
	77	goto retry;
	78	}
	79
	80	if (size > 0) {
7221fe4c	81	acl = posix_acl_from_xattr(&init_user_ns, value, size);
f017754d	82	} else if (size == -ENODATA \|\| size == 0) {
7221fe4c	83	acl = NULL;
f017754d CX	84	} else {
	85	pr_err_ratelimited("get acl %llx.%llx failed, err=%d\n",
	86	ceph_vinop(inode), size);
7221fe4c	87	acl = ERR_PTR(-EIO);
f017754d	88	}
7221fe4c GZ	89
	90	kfree(value);
	91
	92	if (!IS_ERR(acl))
	93	ceph_set_cached_acl(inode, type, acl);
	94
	95	return acl;
	96	}
	97
72466d0b	98	int ceph_set_acl(struct inode inode, struct posix_acl acl, int type)
7221fe4c GZ	99	{
	100	int ret = 0, size = 0;
	101	const char *name = NULL;
	102	char *value = NULL;
	103	struct iattr newattrs;
93d35c75	104	struct timespec64 old_ctime = inode->i_ctime;
7221fe4c GZ	105	umode_t new_mode = inode->i_mode, old_mode = inode->i_mode;
7221fe4c GZ	106
5da20799 CX	107	if (ceph_snap(inode) != CEPH_NOSNAP) {
	108	ret = -EROFS;
	109	goto out;
	110	}
	111
7221fe4c GZ	112	switch (type) {
7221fe4c GZ	113	case ACL_TYPE_ACCESS:
97d79299	114	name = XATTR_NAME_POSIX_ACL_ACCESS;
7221fe4c	115	if (acl) {
07393101 JK	116	ret = posix_acl_update_mode(inode, &new_mode, &acl);
07393101 JK	117	if (ret)
7221fe4c	118	goto out;
7221fe4c GZ	119	}
	120	break;
	121	case ACL_TYPE_DEFAULT:
	122	if (!S_ISDIR(inode->i_mode)) {
	123	ret = acl ? -EINVAL : 0;
	124	goto out;
	125	}
97d79299	126	name = XATTR_NAME_POSIX_ACL_DEFAULT;
7221fe4c GZ	127	break;
	128	default:
	129	ret = -EINVAL;
	130	goto out;
	131	}
	132
	133	if (acl) {
	134	size = posix_acl_xattr_size(acl->a_count);
	135	value = kmalloc(size, GFP_NOFS);
	136	if (!value) {
	137	ret = -ENOMEM;
	138	goto out;
	139	}
	140
	141	ret = posix_acl_to_xattr(&init_user_ns, acl, value, size);
	142	if (ret < 0)
	143	goto out_free;
	144	}
	145
	146	if (new_mode != old_mode) {
4ca2fea6	147	newattrs.ia_ctime = current_time(inode);
7221fe4c	148	newattrs.ia_mode = new_mode;
93d35c75	149	newattrs.ia_valid = ATTR_MODE \| ATTR_CTIME;
a26fecca	150	ret = __ceph_setattr(inode, &newattrs);
7221fe4c	151	if (ret)
a26fecca	152	goto out_free;
7221fe4c GZ	153	}
7221fe4c GZ	154
a26fecca	155	ret = __ceph_setxattr(inode, name, value, size, 0);
7221fe4c GZ	156	if (ret) {
7221fe4c GZ	157	if (new_mode != old_mode) {
93d35c75	158	newattrs.ia_ctime = old_ctime;
7221fe4c	159	newattrs.ia_mode = old_mode;
93d35c75	160	newattrs.ia_valid = ATTR_MODE \| ATTR_CTIME;
a26fecca	161	__ceph_setattr(inode, &newattrs);
7221fe4c	162	}
a26fecca	163	goto out_free;
7221fe4c GZ	164	}
	165
	166	ceph_set_cached_acl(inode, type, acl);
	167
	168	out_free:
	169	kfree(value);
	170	out:
	171	return ret;
	172	}
	173
b1ee94aa YZ	174	int ceph_pre_init_acls(struct inode dir, umode_t mode,
b1ee94aa YZ	175	struct ceph_acls_info *info)
7221fe4c	176	{
b1ee94aa YZ	177	struct posix_acl acl, default_acl;
	178	size_t val_size1 = 0, val_size2 = 0;
	179	struct ceph_pagelist *pagelist = NULL;
	180	void *tmp_buf = NULL;
	181	int err;
	182
	183	err = posix_acl_create(dir, mode, &default_acl, &acl);
	184	if (err)
	185	return err;
	186
	187	if (acl) {
61ad36d4 CX	188	err = posix_acl_equiv_mode(acl, mode);
61ad36d4 CX	189	if (err < 0)
b1ee94aa	190	goto out_err;
61ad36d4	191	if (err == 0) {
b1ee94aa YZ	192	posix_acl_release(acl);
b1ee94aa YZ	193	acl = NULL;
f5f18647	194	}
f5f18647	195	}
7221fe4c	196
b1ee94aa YZ	197	if (!default_acl && !acl)
	198	return 0;
	199
	200	if (acl)
	201	val_size1 = posix_acl_xattr_size(acl->a_count);
	202	if (default_acl)
	203	val_size2 = posix_acl_xattr_size(default_acl->a_count);
	204
	205	err = -ENOMEM;
687265e5	206	tmp_buf = kmalloc(max(val_size1, val_size2), GFP_KERNEL);
b1ee94aa YZ	207	if (!tmp_buf)
b1ee94aa YZ	208	goto out_err;
33165d47	209	pagelist = ceph_pagelist_alloc(GFP_KERNEL);
b1ee94aa YZ	210	if (!pagelist)
b1ee94aa YZ	211	goto out_err;
b1ee94aa YZ	212
	213	err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
	214	if (err)
	215	goto out_err;
	216
	217	ceph_pagelist_encode_32(pagelist, acl && default_acl ? 2 : 1);
	218
75858236	219	if (acl) {
97d79299	220	size_t len = strlen(XATTR_NAME_POSIX_ACL_ACCESS);
b1ee94aa YZ	221	err = ceph_pagelist_reserve(pagelist, len + val_size1 + 8);
	222	if (err)
	223	goto out_err;
97d79299	224	ceph_pagelist_encode_string(pagelist, XATTR_NAME_POSIX_ACL_ACCESS,
b1ee94aa YZ	225	len);
	226	err = posix_acl_to_xattr(&init_user_ns, acl,
	227	tmp_buf, val_size1);
	228	if (err < 0)
	229	goto out_err;
	230	ceph_pagelist_encode_32(pagelist, val_size1);
	231	ceph_pagelist_append(pagelist, tmp_buf, val_size1);
75858236	232	}
b1ee94aa	233	if (default_acl) {
97d79299	234	size_t len = strlen(XATTR_NAME_POSIX_ACL_DEFAULT);
b1ee94aa YZ	235	err = ceph_pagelist_reserve(pagelist, len + val_size2 + 8);
	236	if (err)
	237	goto out_err;
	238	err = ceph_pagelist_encode_string(pagelist,
97d79299	239	XATTR_NAME_POSIX_ACL_DEFAULT, len);
b1ee94aa YZ	240	err = posix_acl_to_xattr(&init_user_ns, default_acl,
	241	tmp_buf, val_size2);
	242	if (err < 0)
	243	goto out_err;
	244	ceph_pagelist_encode_32(pagelist, val_size2);
	245	ceph_pagelist_append(pagelist, tmp_buf, val_size2);
	246	}
	247
	248	kfree(tmp_buf);
	249
	250	info->acl = acl;
	251	info->default_acl = default_acl;
	252	info->pagelist = pagelist;
	253	return 0;
	254
	255	out_err:
	256	posix_acl_release(acl);
	257	posix_acl_release(default_acl);
	258	kfree(tmp_buf);
	259	if (pagelist)
	260	ceph_pagelist_release(pagelist);
	261	return err;
	262	}
	263
	264	void ceph_init_inode_acls(struct inode* inode, struct ceph_acls_info *info)
	265	{
	266	if (!inode)
	267	return;
	268	ceph_set_cached_acl(inode, ACL_TYPE_ACCESS, info->acl);
	269	ceph_set_cached_acl(inode, ACL_TYPE_DEFAULT, info->default_acl);
	270	}
	271
	272	void ceph_release_acls_info(struct ceph_acls_info *info)
	273	{
	274	posix_acl_release(info->acl);
	275	posix_acl_release(info->default_acl);
	276	if (info->pagelist)
	277	ceph_pagelist_release(info->pagelist);
7221fe4c	278	}