From 8eb0243fe65c82ce5c680766a1ffef12e7807aaf Mon Sep 17 00:00:00 2001
From: Alan Cox <alan@linux.intel.com>
Date: Thu, 19 Feb 2015 22:49:47 +0000
Subject: [PATCH] swap, bankfixed: move the swapin/out methods to the memory
 manager

---
 Kernel/bankfixed.c | 69 ++++++++++++++++++++++++++++++++++++++++++
 Kernel/swap.c      | 75 +++++-----------------------------------------
 2 files changed, 77 insertions(+), 67 deletions(-)

diff --git a/Kernel/bankfixed.c b/Kernel/bankfixed.c
index 758dfd45..a38e909e 100644
--- a/Kernel/bankfixed.c
+++ b/Kernel/bankfixed.c
@@ -33,6 +33,10 @@
 
 #ifdef CONFIG_BANK_FIXED
 
+#ifndef CONFIG_COMMON_COPY
+#define flush_cache(p)	do {} while(0)
+#endif
+
 /* Kernel is 0, apps 1,2,3 etc */
 static unsigned char pfree[MAX_MAPS];
 static unsigned char pfptr = 0;
@@ -77,4 +81,69 @@ uint16_t pagemap_mem_used(void)
 	return (pfmax - pfptr) * (MAP_SIZE >> 10);
 }
 
+/*
+ *	Swap out the memory of a process to make room
+ *	for something else
+ */
+int swapout(ptptr p)
+{
+	uint16_t page = p->p_page;
+	uint16_t blk;
+	uint16_t map;
+
+	swapproc = p;
+
+	if (page) {
+#ifdef DEBUG
+		kprintf("Swapping out %x (%d)\n", p, p->p_page);
+#endif
+		/* Are we out of swap ? */
+		map = swapmap_alloc();
+		if (map == 0)
+			return ENOMEM;
+                flush_cache(p);
+		blk = map * SWAP_SIZE;
+		/* Write the app (and possibly the uarea etc..) to disk */
+		swapwrite(SWAPDEV, blk, SWAPTOP - SWAPBASE,
+			  SWAPBASE);
+		pagemap_free(p);
+		p->p_page = 0;
+		p->p_page2 = map;
+#ifdef DEBUG
+		kprintf("%x: swapout done %d\n", p, p->p_page);
+#endif
+	}
+#ifdef DEBUG
+	else
+		kprintf("%x: process already swapped!\n", p);
+#endif
+	return 0;
+}
+
+/*
+ * Swap ourself in: must be on the swap stack when we do this
+ */
+void swapin(ptptr p)
+{
+	uint16_t blk = p->p_page2 * SWAP_SIZE;
+
+#ifdef DEBUG
+	kprintf("Swapin %x, %d\n", p, p->p_page);
+#endif
+	if (!p->p_page) {
+		kprintf("%x: nopage!\n", p);
+		return;
+	}
+
+	/* Return our swap */
+	swapmap_add(p->p_page2);
+
+	swapproc = p;		/* always ourself */
+	swapread(SWAPDEV, blk, SWAPTOP - SWAPBASE,
+		 SWAPBASE);
+#ifdef DEBUG
+	kprintf("%x: swapin done %d\n", p, p->p_page);
+#endif
+}
+
 #endif
diff --git a/Kernel/swap.c b/Kernel/swap.c
index 9b6eaef7..bac72ed4 100644
--- a/Kernel/swap.c
+++ b/Kernel/swap.c
@@ -11,9 +11,6 @@
 
 #ifdef SWAPDEV
 
-#ifndef CONFIG_COMMON_COPY
-#define flush_cache(p)	do {} while(0)
-#endif
 
 uint8_t *swapbase;
 unsigned int swapcnt;
@@ -31,6 +28,14 @@ void swapmap_add(uint8_t swap)
 	swapmap[swapptr++] = swap;
 }
 
+int swapmap_alloc(void)
+{
+        if (swapptr)
+                return swapmap[--swapptr];
+        else
+                return 0;
+}
+
 int swapread(uint16_t dev, blkno_t blkno, unsigned int nbytes,
                     uint8_t *buf)
 {
@@ -50,70 +55,6 @@ int swapwrite(uint16_t dev, blkno_t blkno, unsigned int nbytes,
 	return ((*dev_tab[major(dev)].dev_write) (minor(dev), 2, 0));
 }
 
-/*
- *	Swap out the memory of a process to make room
- *	for something else
- */
-int swapout(ptptr p)
-{
-	uint16_t page = p->p_page;
-	uint16_t blk;
-	uint16_t map;
-
-	swapproc = p;
-
-	if (page) {
-#ifdef DEBUG
-		kprintf("Swapping out %x (%d)\n", p, p->p_page);
-#endif
-		/* Are we out of swap ? */
-		if (swapptr == 0)
-			return ENOMEM;
-                flush_cache(p);
-		map = swapmap[--swapptr];
-		blk = map * SWAP_SIZE;
-		/* Write the app (and possibly the uarea etc..) to disk */
-		swapwrite(SWAPDEV, blk, SWAPTOP - SWAPBASE,
-			  SWAPBASE);
-		pagemap_free(p);
-		p->p_page = 0;
-		p->p_page2 = map;
-#ifdef DEBUG
-		kprintf("%x: swapout done %d\n", p, p->p_page);
-#endif
-	}
-#ifdef DEBUG
-	else
-		kprintf("%x: process already swapped!\n", p);
-#endif
-	return 0;
-}
-
-/*
- * Swap ourself in: must be on the swap stack when we do this
- */
-void swapin(ptptr p)
-{
-	uint16_t blk = p->p_page2 * SWAP_SIZE;
-
-#ifdef DEBUG
-	kprintf("Swapin %x, %d\n", p, p->p_page);
-#endif
-	if (!p->p_page) {
-		kprintf("%x: nopage!\n", p);
-		return;
-	}
-
-	/* Return our swap */
-	swapmap[swapptr++] = p->p_page2;
-
-	swapproc = p;		/* always ourself */
-	swapread(SWAPDEV, blk, SWAPTOP - SWAPBASE,
-		 SWAPBASE);
-#ifdef DEBUG
-	kprintf("%x: swapin done %d\n", p, p->p_page);
-#endif
-}
 
 /*
  *	Swap out process. As we have them all the same size we ignore
-- 
2.34.1