diff options
Diffstat (limited to 'fs/ceph/acl.c')
| -rw-r--r-- | fs/ceph/acl.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/fs/ceph/acl.c b/fs/ceph/acl.c new file mode 100644 index 000000000000..21887d63dad5 --- /dev/null +++ b/fs/ceph/acl.c @@ -0,0 +1,200 @@ +/* + * 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; + + if (acl) { + ret = posix_acl_valid(acl); + if (ret < 0) + goto out; + } + + 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; +} |