Use extended crashkernel command line on i386

This patch removes the crashkernel parsing from
arch/i386/kernel/machine_kexec.c and calls the generic function, introduced in
the last patch, in setup_bootmem_allocator().

This is necessary because the amount of System RAM must be known in this
function now because of the new syntax.
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/x86/kernel/e820_32.c

@@ -288,7 +288,8 @@ legacy_init_iomem_resources(struct resource *code_resource, struct resource *dat
 			request_resource(res, code_resource);
 			request_resource(res, data_resource);
 #ifdef CONFIG_KEXEC
-			request_resource(res, &crashk_res);
+			if (crashk_res.start != crashk_res.end)
+				request_resource(res, &crashk_res);
 #endif
 		}
 	}

arch/x86/kernel/machine_kexec_32.c

@@ -149,28 +149,6 @@ NORET_TYPE void machine_kexec(struct kimage *image)
 			image->start, cpu_has_pae);
 }
 
-/* crashkernel=size@addr specifies the location to reserve for
- * a crash kernel.  By reserving this memory we guarantee
- * that linux never sets it up as a DMA target.
- * Useful for holding code to do something appropriate
- * after a kernel panic.
- */
-static int __init parse_crashkernel(char *arg)
-{
-	unsigned long size, base;
-	size = memparse(arg, &arg);
-	if (*arg == '@') {
-		base = memparse(arg+1, &arg);
-		/* FIXME: Do I want a sanity check
-		 * to validate the memory range?
-		 */
-		crashk_res.start = base;
-		crashk_res.end   = base + size - 1;
-	}
-	return 0;
-}
-early_param("crashkernel", parse_crashkernel);
-
 void arch_crash_save_vmcoreinfo(void)
 {
 #ifdef CONFIG_ARCH_DISCONTIGMEM_ENABLE

arch/x86/kernel/setup_32.c

@@ -378,6 +378,49 @@ extern unsigned long __init setup_memory(void);
 extern void zone_sizes_init(void);
 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 
+static inline unsigned long long get_total_mem(void)
+{
+	unsigned long long total;
+
+	total = max_low_pfn - min_low_pfn;
+#ifdef CONFIG_HIGHMEM
+	total += highend_pfn - highstart_pfn;
+#endif
+
+	return total << PAGE_SHIFT;
+}
+
+#ifdef CONFIG_KEXEC
+static void __init reserve_crashkernel(void)
+{
+	unsigned long long total_mem;
+	unsigned long long crash_size, crash_base;
+	int ret;
+
+	total_mem = get_total_mem();
+
+	ret = parse_crashkernel(boot_command_line, total_mem,
+			&crash_size, &crash_base);
+	if (ret == 0 && crash_size > 0) {
+		if (crash_base > 0) {
+			printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
+					"for crashkernel (System RAM: %ldMB)\n",
+					(unsigned long)(crash_size >> 20),
+					(unsigned long)(crash_base >> 20),
+					(unsigned long)(total_mem >> 20));
+			crashk_res.start = crash_base;
+			crashk_res.end   = crash_base + crash_size - 1;
+			reserve_bootmem(crash_base, crash_size);
+		} else
+			printk(KERN_INFO "crashkernel reservation failed - "
+					"you have to specify a base address\n");
+	}
+}
+#else
+static inline void __init reserve_crashkernel(void)
+{}
+#endif
+
 void __init setup_bootmem_allocator(void)
 {
 	unsigned long bootmap_size;
@@ -453,11 +496,7 @@ void __init setup_bootmem_allocator(void)
 		}
 	}
 #endif
-#ifdef CONFIG_KEXEC
-	if (crashk_res.start != crashk_res.end)
-		reserve_bootmem(crashk_res.start,
-			crashk_res.end - crashk_res.start + 1);
-#endif
+	reserve_crashkernel();
 }
 
 /*