More sys_mmap2 madness. Different architectures implement this differently.
Not only is the shift count inconsistent, but some architectures test that
the offset is valid, others don't, so do it ourselves.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/klibc/mmap.c b/klibc/mmap.c
index da11c70..2412e32 100644
--- a/klibc/mmap.c
+++ b/klibc/mmap.c
@@ -10,19 +10,23 @@
#include <bitsize.h>
/*
- * MMAP2_SHIFT is definitely *NOT* equal to getpageshift() for
- * at least some architectures...
- */
-#if defined(__i386__) || defined( __sparc__) || defined(__arm__)
-# define MMAP2_SHIFT 12 /* Fixed by syscall definition */
-#endif
-
-/*
* Set in SYSCALLS whether or not we should use an unadorned mmap() system
* call (typical on 64-bit architectures).
*/
#if (_BITSIZE == 32 && defined(__NR_mmap2)) || (_BITSIZE == 64 && !defined(__NR_mmap))
+/*
+ * Some architectures use a fixed value for MMAP2_SHIFT, other use the
+ * current page size. This, of course, isn't documented or even
+ * #define'd anywhere.
+ */
+#if defined(__cris__) || defined(__m68k__) || defined(__mips__)
+/* Use the current page size */
+#else
+# define MMAP2_SHIFT 12 /* Fixed by syscall definition */
+#endif
+
+
/* This architecture uses mmap2(). The Linux mmap2() system call takes
a page offset as the offset argument. We need to make sure we have
the proper conversion in place. */
@@ -33,12 +37,12 @@
{
#ifdef MMAP2_SHIFT
const int mmap2_shift = MMAP2_SHIFT;
- const unsigned long mmap2_mask = (1UL << mmap2_shift) - 1;
#else
- extern unsigned int __page_size, __page_shift;
+ extern unsigned int __page_shift;
const int mmap2_shift = __page_shift;
- const unsigned long mmap2_mask = (unsigned long)__page_size - 1;
#endif
+ extern unsigned int __page_size;
+ const unsigned int mmap2_mask = __page_size - 1;
if ( offset & mmap2_mask ) {
errno = EINVAL;
