patch-1.3.31 linux/arch/i386/mm/init.c

• Lines: 67
• Date: Mon Oct 2 14:25:10 1995
• Orig file: v1.3.30/linux/arch/i386/mm/init.c
• Orig date: Mon Sep 25 12:26:21 1995

diff -u --recursive --new-file v1.3.30/linux/arch/i386/mm/init.c linux/arch/i386/mm/init.c
@@ -15,6 +15,7 @@
 #include <linux/ptrace.h>
 #include <linux/mman.h>
 #include <linux/mm.h>
+#include <linux/smp.h>
 
 #include <asm/system.h>
 #include <asm/segment.h>
@@ -111,10 +112,27 @@
  * and SMM (for laptops with [34]86/SL chips) may need it.  It is read
  * and write protected to detect null pointer references in the
  * kernel.
+ * It may also hold the MP configuration table when we are booting SMP.
  */
 #if 0
 	memset((void *) 0, 0, PAGE_SIZE);
 #endif
+#ifdef CONFIG_SMP
+	smp_scan_config(0x0,0x400);	/* Scan the bottom 1K for a signature */
+	/*
+	 *	FIXME: Linux assumes you have 640K of base ram.. this continues
+	 *	the error...
+	 */
+	smp_scan_config(639*0x400,0x400);	/* Scan the top 1K of base RAM */
+	smp_scan_config(0xF0000,0x10000);	/* Scan the 64K of bios */
+	/*
+	 *	If it is an SMP machine we should know now, unless the configuration
+	 *	is in an EISA/MCA bus machine with an extended bios data area. I don't
+	 *	have such a machine so someone else can fill in the check of the EBDA
+	 *	here.
+	 */
+/*	smp_alloc_memory(8192); */
+#endif
 #ifdef CONFIG_TEST_VERIFY_AREA
 	wp_works_ok = 0;
 #endif
@@ -123,6 +141,7 @@
 	pg_dir = swapper_pg_dir;
 	while (address < end_mem) {
 #ifdef CONFIG_PENTIUM_MM
+#ifndef CONFIG_SMP
 		if (address <= end_mem + 4*1024*1024 &&
 		    (x86_capability & 8)) {
 #ifdef GAS_KNOWS_CR4
@@ -144,6 +163,7 @@
 			continue;
 		}
 #endif
+#endif
 		/* map the memory at virtual addr 0xC0000000 */
 		pg_table = (pte_t *) (PAGE_MASK & pgd_val(pg_dir[768]));
 		if (!pg_table) {
@@ -184,6 +204,14 @@
 
 	/* mark usable pages in the mem_map[] */
 	start_low_mem = PAGE_ALIGN(start_low_mem);
+
+#ifdef CONFIG_SMP
+	/*
+	 * But first pinch a few for the stack/trampoline stuff
+	 */
+	start_low_mem += PAGE_SIZE;				/* 32bit startup code */
+	start_low_mem = smp_alloc_memory(start_low_mem); 	/* AP processor stacks */
+#endif
 	start_mem = PAGE_ALIGN(start_mem);
 
 	/*