Port 0.8.50 acl-xattr patch to 2.5 (harmonize header file with SGI/XFS)

This patch provides converts extended attributes passed in from user
space to a generic Posix ACL representation.

2 files changed, 105 insertions, 0 deletions

diff --git a/include/linux/posix_acl_xattr.h b/include/linux/posix_acl_xattr.h
new file mode 100644
index 000000000000..5efd0a6dad94
--- /dev/null
+++ b/include/linux/posix_acl_xattr.h
@@ -0,0 +1,55 @@
+/*
+  File: linux/posix_acl_xattr.h
+
+  Extended attribute system call representation of Access Control Lists.
+
+  Copyright (C) 2000 by Andreas Gruenbacher <a.gruenbacher@computer.org>
+  Copyright (C) 2002 SGI - Silicon Graphics, Inc <linux-xfs@oss.sgi.com>
+ */
+#ifndef _POSIX_ACL_XATTR_H
+#define _POSIX_ACL_XATTR_H
+
+#include <linux/posix_acl.h>
+
+/* Extended attribute names */
+#define POSIX_ACL_XATTR_ACCESS	"system.posix_acl_access"
+#define POSIX_ACL_XATTR_DEFAULT	"system.posix_acl_default"
+
+/* Supported ACL a_version fields */
+#define POSIX_ACL_XATTR_VERSION	0x0002
+
+
+/* An undefined entry e_id value */
+#define ACL_UNDEFINED_ID	(-1)
+
+typedef struct {
+	__u16			e_tag;
+	__u16			e_perm;
+	__u32			e_id;
+} posix_acl_xattr_entry;
+
+typedef struct {
+	__u32			a_version;
+	posix_acl_xattr_entry	a_entries[0];
+} posix_acl_xattr_header;
+
+
+static inline size_t
+posix_acl_xattr_size(int count)
+{
+	return (sizeof(posix_acl_xattr_header) +
+		(count * sizeof(posix_acl_xattr_entry)));
+}
+
+static inline int
+posix_acl_xattr_count(size_t size)
+{
+	if (size < sizeof(posix_acl_xattr_header))
+		return -1;
+	size -= sizeof(posix_acl_xattr_header);
+	if (size % sizeof(posix_acl_xattr_entry))
+		return -1;
+	return size / sizeof(posix_acl_xattr_entry);
+}
+
+#endif	/* _POSIX_ACL_XATTR_H */
diff --git a/include/linux/xattr_acl.h b/include/linux/xattr_acl.h
new file mode 100644
index 000000000000..7a1f9b93a45f
--- /dev/null
+++ b/include/linux/xattr_acl.h
@@ -0,0 +1,50 @@
+/*
+  File: linux/xattr_acl.h
+
+  (extended attribute representation of access control lists)
+
+  (C) 2000 Andreas Gruenbacher, <a.gruenbacher@computer.org>
+*/
+
+#ifndef _LINUX_XATTR_ACL_H
+#define _LINUX_XATTR_ACL_H
+
+#include <linux/posix_acl.h>
+
+#define XATTR_NAME_ACL_ACCESS	"system.posix_acl_access"
+#define XATTR_NAME_ACL_DEFAULT	"system.posix_acl_default"
+
+#define XATTR_ACL_VERSION	0x0002
+
+typedef struct {
+	__u16		e_tag;
+	__u16		e_perm;
+	__u32		e_id;
+} xattr_acl_entry;
+
+typedef struct {
+	__u32		a_version;
+	xattr_acl_entry	a_entries[0];
+} xattr_acl_header;
+
+static inline size_t xattr_acl_size(int count)
+{
+	return sizeof(xattr_acl_header) + count * sizeof(xattr_acl_entry);
+}
+
+static inline int xattr_acl_count(size_t size)
+{
+	if (size < sizeof(xattr_acl_header))
+		return -1;
+	size -= sizeof(xattr_acl_header);
+	if (size % sizeof(xattr_acl_entry))
+		return -1;
+	return size / sizeof(xattr_acl_entry);
+}
+
+struct posix_acl * posix_acl_from_xattr(const void *value, size_t size);
+int posix_acl_to_xattr(const struct posix_acl *acl, void *buffer, size_t size);
+
+
+
+#endif /* _LINUX_XATTR_ACL_H */