[PATCH 2.6] Make linux/swap.h usable by userspace code.

From: Steven J. Hill
Date: Mon Mar 01 2004 - 09:34:58 EST


Greetings.

This patch allows 'swap.h' to be included by userspace code. AFAIK the
LTP suite is the only code that does this so far.

-Steve --- linux/include/linux/swap.h Thu Feb 5 17:46:32 2004
+++ linux-new/include/linux/swap.h Mon Mar 1 09:00:35 2004
@@ -2,6 +2,20 @@
#define _LINUX_SWAP_H

#include <linux/config.h>
+
+/*
+ * MAX_SWAPFILES defines the maximum number of swaptypes: things which can
+ * be swapped to. The swap type and the offset into that swap type are
+ * encoded into pte's and into pgoff_t's in the swapcache. Using five bits
+ * for the type means that the maximum number of swapcache pages is 27 bits
+ * on 32-bit-pgoff_t architectures. And that assumes that the architecture packs
+ * the type/offset into the pte as 5/27 as well.
+ */
+#define MAX_SWAPFILES_SHIFT 5
+#define MAX_SWAPFILES (1 << MAX_SWAPFILES_SHIFT)
+
+#ifdef __KERNEL__
+
#include <linux/spinlock.h>
#include <linux/linkage.h>
#include <linux/mmzone.h>
@@ -20,17 +34,6 @@
}

/*
- * MAX_SWAPFILES defines the maximum number of swaptypes: things which can
- * be swapped to. The swap type and the offset into that swap type are
- * encoded into pte's and into pgoff_t's in the swapcache. Using five bits
- * for the type means that the maximum number of swapcache pages is 27 bits
- * on 32-bit-pgoff_t architectures. And that assumes that the architecture packs
- * the type/offset into the pte as 5/27 as well.
- */
-#define MAX_SWAPFILES_SHIFT 5
-#define MAX_SWAPFILES (1 << MAX_SWAPFILES_SHIFT)
-
-/*
* Magic header for a swap area. The first part of the union is
* what the swap magic looks like for the old (limited to 128MB)
* swap area format, the second part of the union adds - in the
@@ -72,8 +75,6 @@
struct reclaim_state {
unsigned long reclaimed_slab;
};
-
-#ifdef __KERNEL__

struct address_space;
struct pte_chain;