ceph: add acl for cephfs

Signed-off-by: Guangliang Zhao <lucienchao@gmail.com>
Reviewed-by: Li Wang <li.wang@ubuntykylin.com>
Reviewed-by: Zheng Yan <zheng.z.yan@intel.com>
diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index be661d8..c7581f37 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -11,11 +11,24 @@
 #define XATTR_CEPH_PREFIX "ceph."
 #define XATTR_CEPH_PREFIX_LEN (sizeof (XATTR_CEPH_PREFIX) - 1)
 
+/*
+ * List of handlers for synthetic system.* attributes. Other
+ * attributes are handled directly.
+ */
+const struct xattr_handler *ceph_xattr_handlers[] = {
+#ifdef CONFIG_CEPH_FS_POSIX_ACL
+	&ceph_xattr_acl_access_handler,
+	&ceph_xattr_acl_default_handler,
+#endif
+	NULL,
+};
+
 static bool ceph_is_valid_xattr(const char *name)
 {
 	return !strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN) ||
 	       !strncmp(name, XATTR_SECURITY_PREFIX,
 			XATTR_SECURITY_PREFIX_LEN) ||
+	       !strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN) ||
 	       !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) ||
 	       !strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
 }
@@ -663,10 +676,9 @@
 	}
 }
 
-ssize_t ceph_getxattr(struct dentry *dentry, const char *name, void *value,
+ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 		      size_t size)
 {
-	struct inode *inode = dentry->d_inode;
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	int err;
 	struct ceph_inode_xattr *xattr;
@@ -675,7 +687,6 @@
 	if (!ceph_is_valid_xattr(name))
 		return -ENODATA;
 
-
 	/* let's see if a virtual xattr was requested */
 	vxattr = ceph_match_vxattr(inode, name);
 	if (vxattr && !(vxattr->exists_cb && !vxattr->exists_cb(ci))) {
@@ -725,6 +736,15 @@
 	return err;
 }
 
+ssize_t ceph_getxattr(struct dentry *dentry, const char *name, void *value,
+		      size_t size)
+{
+	if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
+		return generic_getxattr(dentry, name, value, size);
+
+	return __ceph_getxattr(dentry->d_inode, name, value, size);
+}
+
 ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
 {
 	struct inode *inode = dentry->d_inode;
@@ -863,8 +883,8 @@
 	return err;
 }
 
-int ceph_setxattr(struct dentry *dentry, const char *name,
-		  const void *value, size_t size, int flags)
+int __ceph_setxattr(struct dentry *dentry, const char *name,
+			const void *value, size_t size, int flags)
 {
 	struct inode *inode = dentry->d_inode;
 	struct ceph_vxattr *vxattr;
@@ -879,9 +899,6 @@
 	struct ceph_inode_xattr *xattr = NULL;
 	int required_blob_size;
 
-	if (ceph_snap(inode) != CEPH_NOSNAP)
-		return -EROFS;
-
 	if (!ceph_is_valid_xattr(name))
 		return -EOPNOTSUPP;
 
@@ -958,6 +975,18 @@
 	return err;
 }
 
+int ceph_setxattr(struct dentry *dentry, const char *name,
+		  const void *value, size_t size, int flags)
+{
+	if (ceph_snap(dentry->d_inode) != CEPH_NOSNAP)
+		return -EROFS;
+
+	if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
+		return generic_setxattr(dentry, name, value, size, flags);
+
+	return __ceph_setxattr(dentry, name, value, size, flags);
+}
+
 static int ceph_send_removexattr(struct dentry *dentry, const char *name)
 {
 	struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
@@ -984,7 +1013,7 @@
 	return err;
 }
 
-int ceph_removexattr(struct dentry *dentry, const char *name)
+int __ceph_removexattr(struct dentry *dentry, const char *name)
 {
 	struct inode *inode = dentry->d_inode;
 	struct ceph_vxattr *vxattr;
@@ -994,9 +1023,6 @@
 	int required_blob_size;
 	int dirty;
 
-	if (ceph_snap(inode) != CEPH_NOSNAP)
-		return -EROFS;
-
 	if (!ceph_is_valid_xattr(name))
 		return -EOPNOTSUPP;
 
@@ -1053,3 +1079,13 @@
 	return err;
 }
 
+int ceph_removexattr(struct dentry *dentry, const char *name)
+{
+	if (ceph_snap(dentry->d_inode) != CEPH_NOSNAP)
+		return -EROFS;
+
+	if (!strncmp(name, XATTR_SYSTEM_PREFIX, XATTR_SYSTEM_PREFIX_LEN))
+		return generic_removexattr(dentry, name);
+
+	return __ceph_removexattr(dentry, name);
+}