diff options
Diffstat (limited to 'fs/ceph/acl.c')
| -rw-r--r-- | fs/ceph/acl.c | 194 | 
1 files changed, 194 insertions, 0 deletions
diff --git a/fs/ceph/acl.c b/fs/ceph/acl.c new file mode 100644 index 00000000000..469f2e8657e --- /dev/null +++ b/fs/ceph/acl.c @@ -0,0 +1,194 @@ +/* + * linux/fs/ceph/acl.c + * + * Copyright (C) 2013 Guangliang Zhao, <lucienchao@gmail.com> + * + * 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); +} + +static inline struct posix_acl *ceph_get_cached_acl(struct inode *inode, +							int type) +{ +	struct ceph_inode_info *ci = ceph_inode(inode); +	struct posix_acl *acl = ACL_NOT_CACHED; + +	spin_lock(&ci->i_ceph_lock); +	if (__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 0)) +		acl = get_cached_acl(inode, type); +	spin_unlock(&ci->i_ceph_lock); + +	return acl; +} + +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_init_acl(struct dentry *dentry, struct inode *inode, struct inode *dir) +{ +	struct posix_acl *default_acl, *acl; +	int error; + +	error = posix_acl_create(dir, &inode->i_mode, &default_acl, &acl); +	if (error) +		return error; + +	if (!default_acl && !acl) +		cache_no_acl(inode); + +	if (default_acl) { +		error = ceph_set_acl(inode, default_acl, ACL_TYPE_DEFAULT); +		posix_acl_release(default_acl); +	} +	if (acl) { +		if (!error) +			error = ceph_set_acl(inode, acl, ACL_TYPE_ACCESS); +		posix_acl_release(acl); +	} +	return error; +}  | 
