linux.c32: make load_linux() support relocation

In the case where the preferred kernel locations are not available,
make load_linux() smart enough to be able to relocate the kernel if at
all possible.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 47 insertions, 0 deletions

diff --git a/com32/include/syslinux/align.h b/com32/include/syslinux/align.h
new file mode 100644
index 00000000..5b01bf27
--- /dev/null
+++ b/com32/include/syslinux/align.h
@@ -0,0 +1,47 @@
+/* ----------------------------------------------------------------------- *
+ *
+ *   Copyright 2009 Intel Corporation; author H. Peter Anvin
+ *
+ *   Permission is hereby granted, free of charge, to any person
+ *   obtaining a copy of this software and associated documentation
+ *   files (the "Software"), to deal in the Software without
+ *   restriction, including without limitation the rights to use,
+ *   copy, modify, merge, publish, distribute, sublicense, and/or
+ *   sell copies of the Software, and to permit persons to whom
+ *   the Software is furnished to do so, subject to the following
+ *   conditions:
+ *
+ *   The above copyright notice and this permission notice shall
+ *   be included in all copies or substantial portions of the Software.
+ *
+ *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ *   OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ *   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ *   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ *   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ *   OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * ----------------------------------------------------------------------- */
+
+#ifndef _SYSLINUX_ALIGN_H
+#define _SYSLINUX_ALIGN_H
+
+#include <stdint.h>
+
+static inline uintptr_t __align_down(uintptr_t __p, uintptr_t __a)
+{
+  return __p & ~(__a - 1);
+}
+static inline uintptr_t __align_up(uintptr_t __p, uintptr_t __a)
+{
+  return (__p + __a - 1) & ~(__a - 1);
+}
+
+#define ALIGN_UP(p,a) ((__typeof__(p))__align_up((uintptr_t)(p), (a)))
+#define ALIGN_DOWN(p,a) ((__typeof__(p))__align_down((uintptr_t)(p), (a)))
+#define ALIGN_UP_FOR(p,t) ALIGN_UP(p,sizeof(t))
+#define ALIGN_DOWN_FOR(p,t) ALIGN_DOWN(p,sizeof(t))
+
+#endif /* _SYSLINUX_ALIGN_H */