summaryrefslogtreecommitdiff
path: root/include/vdso/page.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/vdso/page.h')
-rw-r--r--include/vdso/page.h31
1 files changed, 31 insertions, 0 deletions
diff --git a/include/vdso/page.h b/include/vdso/page.h
new file mode 100644
index 000000000000..710ae2414e68
--- /dev/null
+++ b/include/vdso/page.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_PAGE_H
+#define __VDSO_PAGE_H
+
+#include <uapi/linux/const.h>
+
+/*
+ * PAGE_SHIFT determines the page size.
+ *
+ * Note: This definition is required because PAGE_SHIFT is used
+ * in several places throuout the codebase.
+ */
+#define PAGE_SHIFT CONFIG_PAGE_SHIFT
+
+#define PAGE_SIZE (_AC(1,UL) << CONFIG_PAGE_SHIFT)
+
+#if !defined(CONFIG_64BIT)
+/*
+ * Applies only to 32-bit architectures.
+ *
+ * Subtle: (1 << CONFIG_PAGE_SHIFT) is an int, not an unsigned long.
+ * So if we assign PAGE_MASK to a larger type it gets extended the
+ * way we want (i.e. with 1s in the high bits) while masking a
+ * 64-bit value such as phys_addr_t.
+ */
+#define PAGE_MASK (~((1 << CONFIG_PAGE_SHIFT) - 1))
+#else
+#define PAGE_MASK (~(PAGE_SIZE - 1))
+#endif
+
+#endif /* __VDSO_PAGE_H */