x86: corruption check: move the corruption checks into their own file

Impact: cleanup

The corruption check code is rather sizable and it's likely to grow over
time when we add checks for more types of corruptions (there's a few
candidates in kerneloops.org that I want to add checks for)... so lets move
it to its own file

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

4 files changed, 163 insertions, 152 deletions

diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index f12d37237465..1ed8b2e80727 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -8,6 +8,10 @@
 /* Interrupt control for vSMPowered x86_64 systems */
 void vsmp_init(void);
 
+
+void setup_bios_corruption_check(void);
+
+
 #ifdef CONFIG_X86_VISWS
 extern void visws_early_detect(void);
 extern int is_visws_box(void);
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index d7e5a58ee22f..31fbcaf3df70 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -35,6 +35,7 @@ obj-y			+= bootflag.o e820.o
 obj-y                   += pci-dma.o quirks.o i8237.o topology.o kdebugfs.o
 obj-y                   += alternative.o i8253.o pci-nommu.o
 obj-y                   += tsc.o io_delay.o rtc.o
+obj-y                   += check.o
 
 obj-$(CONFIG_X86_TRAMPOLINE)    += trampoline.o
 obj-y                           += process.o
diff --git a/arch/x86/kernel/check.c b/arch/x86/kernel/check.c
new file mode 100644
index 000000000000..5056703e1b05
--- /dev/null
+++ b/arch/x86/kernel/check.c
@@ -0,0 +1,158 @@
+#include <linux/module.h>
+#include <linux/sched.h>
+
+#include <asm/e820.h>
+#include <asm/proto.h>
+
+/*
+ * Some BIOSes seem to corrupt the low 64k of memory during events
+ * like suspend/resume and unplugging an HDMI cable.  Reserve all
+ * remaining free memory in that area and fill it with a distinct
+ * pattern.
+ */
+#ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
+#define MAX_SCAN_AREAS  8
+
+static int __read_mostly memory_corruption_check = -1;
+
+static unsigned __read_mostly corruption_check_size = 64*1024;
+static unsigned __read_mostly corruption_check_period = 60; /* seconds */
+
+static struct e820entry scan_areas[MAX_SCAN_AREAS];
+static int num_scan_areas;
+
+
+static int set_corruption_check(char *arg)
+{
+        char *end;
+
+        memory_corruption_check = simple_strtol(arg, &end, 10);
+
+        return (*end == 0) ? 0 : -EINVAL;
+}
+early_param("memory_corruption_check", set_corruption_check);
+
+static int set_corruption_check_period(char *arg)
+{
+        char *end;
+
+        corruption_check_period = simple_strtoul(arg, &end, 10);
+
+        return (*end == 0) ? 0 : -EINVAL;
+}
+early_param("memory_corruption_check_period", set_corruption_check_period);
+
+static int set_corruption_check_size(char *arg)
+{
+        char *end;
+        unsigned size;
+
+        size = memparse(arg, &end);
+
+        if (*end == '\0')
+                corruption_check_size = size;
+
+        return (size == corruption_check_size) ? 0 : -EINVAL;
+}
+early_param("memory_corruption_check_size", set_corruption_check_size);
+
+
+void __init setup_bios_corruption_check(void)
+{
+        u64 addr = PAGE_SIZE;   /* assume first page is reserved anyway */
+
+        if (memory_corruption_check == -1) {
+                memory_corruption_check =
+#ifdef CONFIG_X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
+                        1
+#else
+                        0
+#endif
+                        ;
+        }
+
+        if (corruption_check_size == 0)
+                memory_corruption_check = 0;
+
+        if (!memory_corruption_check)
+                return;
+
+        corruption_check_size = round_up(corruption_check_size, PAGE_SIZE);
+
+        while (addr < corruption_check_size && num_scan_areas < MAX_SCAN_AREAS) {
+                u64 size;
+                addr = find_e820_area_size(addr, &size, PAGE_SIZE);
+
+                if (addr == 0)
+                        break;
+
+                if ((addr + size) > corruption_check_size)
+                        size = corruption_check_size - addr;
+
+                if (size == 0)
+                        break;
+
+                e820_update_range(addr, size, E820_RAM, E820_RESERVED);
+                scan_areas[num_scan_areas].addr = addr;
+                scan_areas[num_scan_areas].size = size;
+                num_scan_areas++;
+
+                /* Assume we've already mapped this early memory */
+                memset(__va(addr), 0, size);
+
+                addr += size;
+        }
+
+        printk(KERN_INFO "Scanning %d areas for low memory corruption\n",
+               num_scan_areas);
+        update_e820();
+}
+
+static struct timer_list periodic_check_timer;
+
+void check_for_bios_corruption(void)
+{
+        int i;
+        int corruption = 0;
+
+        if (!memory_corruption_check)
+                return;
+
+        for (i = 0; i < num_scan_areas; i++) {
+                unsigned long *addr = __va(scan_areas[i].addr);
+                unsigned long size = scan_areas[i].size;
+
+                for (; size; addr++, size -= sizeof(unsigned long)) {
+                        if (!*addr)
+                                continue;
+                        printk(KERN_ERR "Corrupted low memory at %p (%lx phys) = %08lx\n",
+                               addr, __pa(addr), *addr);
+                        corruption = 1;
+                        *addr = 0;
+                }
+        }
+
+        WARN(corruption, KERN_ERR "Memory corruption detected in low memory\n");
+}
+
+static void periodic_check_for_corruption(unsigned long data)
+{
+        check_for_bios_corruption();
+        mod_timer(&periodic_check_timer,
+                round_jiffies(jiffies + corruption_check_period*HZ));
+}
+
+void start_periodic_check_for_corruption(void)
+{
+        if (!memory_corruption_check || corruption_check_period == 0)
+                return;
+
+        printk(KERN_INFO "Scanning for low memory corruption every %d seconds\n",
+               corruption_check_period);
+
+        init_timer(&periodic_check_timer);
+        periodic_check_timer.function = &periodic_check_for_corruption;
+        periodic_check_for_corruption(0);
+}
+#endif
+
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 4f38e0305b07..af690aa593a9 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -587,158 +587,6 @@ static struct x86_quirks default_x86_quirks __initdata;
 
 struct x86_quirks *x86_quirks __initdata = &default_x86_quirks;
 
-/*
- * Some BIOSes seem to corrupt the low 64k of memory during events
- * like suspend/resume and unplugging an HDMI cable.  Reserve all
- * remaining free memory in that area and fill it with a distinct
- * pattern.
- */
-#ifdef CONFIG_X86_CHECK_BIOS_CORRUPTION
-#define MAX_SCAN_AREAS  8
-
-static int __read_mostly memory_corruption_check = -1;
-
-static unsigned __read_mostly corruption_check_size = 64*1024;
-static unsigned __read_mostly corruption_check_period = 60; /* seconds */
-
-static struct e820entry scan_areas[MAX_SCAN_AREAS];
-static int num_scan_areas;
-
-
-static int set_corruption_check(char *arg)
-{
-        char *end;
-
-        memory_corruption_check = simple_strtol(arg, &end, 10);
-
-        return (*end == 0) ? 0 : -EINVAL;
-}
-early_param("memory_corruption_check", set_corruption_check);
-
-static int set_corruption_check_period(char *arg)
-{
-        char *end;
-
-        corruption_check_period = simple_strtoul(arg, &end, 10);
-
-        return (*end == 0) ? 0 : -EINVAL;
-}
-early_param("memory_corruption_check_period", set_corruption_check_period);
-
-static int set_corruption_check_size(char *arg)
-{
-        char *end;
-        unsigned size;
-
-        size = memparse(arg, &end);
-
-        if (*end == '\0')
-                corruption_check_size = size;
-
-        return (size == corruption_check_size) ? 0 : -EINVAL;
-}
-early_param("memory_corruption_check_size", set_corruption_check_size);
-
-
-static void __init setup_bios_corruption_check(void)
-{
-        u64 addr = PAGE_SIZE;   /* assume first page is reserved anyway */
-
-        if (memory_corruption_check == -1) {
-                memory_corruption_check =
-#ifdef CONFIG_X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
-                        1
-#else
-                        0
-#endif
-                        ;
-        }
-
-        if (corruption_check_size == 0)
-                memory_corruption_check = 0;
-
-        if (!memory_corruption_check)
-                return;
-
-        corruption_check_size = round_up(corruption_check_size, PAGE_SIZE);
-
-        while (addr < corruption_check_size && num_scan_areas < MAX_SCAN_AREAS) {
-                u64 size;
-                addr = find_e820_area_size(addr, &size, PAGE_SIZE);
-
-                if (addr == 0)
-                        break;
-
-                if ((addr + size) > corruption_check_size)
-                        size = corruption_check_size - addr;
-
-                if (size == 0)
-                        break;
-
-                e820_update_range(addr, size, E820_RAM, E820_RESERVED);
-                scan_areas[num_scan_areas].addr = addr;
-                scan_areas[num_scan_areas].size = size;
-                num_scan_areas++;
-
-                /* Assume we've already mapped this early memory */
-                memset(__va(addr), 0, size);
-
-                addr += size;
-        }
-
-        printk(KERN_INFO "Scanning %d areas for low memory corruption\n",
-               num_scan_areas);
-        update_e820();
-}
-
-static struct timer_list periodic_check_timer;
-
-void check_for_bios_corruption(void)
-{
-        int i;
-        int corruption = 0;
-
-        if (!memory_corruption_check)
-                return;
-
-        for (i = 0; i < num_scan_areas; i++) {
-                unsigned long *addr = __va(scan_areas[i].addr);
-                unsigned long size = scan_areas[i].size;
-
-                for (; size; addr++, size -= sizeof(unsigned long)) {
-                        if (!*addr)
-                                continue;
-                        printk(KERN_ERR "Corrupted low memory at %p (%lx phys) = %08lx\n",
-                               addr, __pa(addr), *addr);
-                        corruption = 1;
-                        *addr = 0;
-                }
-        }
-
-        WARN(corruption, KERN_ERR "Memory corruption detected in low memory\n");
-}
-
-static void periodic_check_for_corruption(unsigned long data)
-{
-        check_for_bios_corruption();
-        mod_timer(&periodic_check_timer,
-                round_jiffies(jiffies + corruption_check_period*HZ));
-}
-
-void start_periodic_check_for_corruption(void)
-{
-        if (!memory_corruption_check || corruption_check_period == 0)
-                return;
-
-        printk(KERN_INFO "Scanning for low memory corruption every %d seconds\n",
-               corruption_check_period);
-
-        init_timer(&periodic_check_timer);
-        periodic_check_timer.function = &periodic_check_for_corruption;
-        periodic_check_for_corruption(0);
-}
-#endif
-
 static int __init dmi_low_memory_corruption(const struct dmi_system_id *d)
 {
         printk(KERN_NOTICE