1 files changed, 20 insertions, 6 deletions

diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 7d46bb260334..e2ce85db2283 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -149,6 +149,9 @@ static void __init e820_print_type(u32 type)
 	case E820_UNUSABLE:
 		printk(KERN_CONT "unusable");
 		break;
+	case E820_PRAM:
+		printk(KERN_CONT "persistent (type %u)", type);
+		break;
 	default:
 		printk(KERN_CONT "type %u", type);
 		break;
@@ -343,7 +346,7 @@ int __init sanitize_e820_map(struct e820entry *biosmap, int max_nr_map,
 		 * continue building up new bios map based on this
 		 * information
 		 */
-		if (current_type != last_type)	{
+		if (current_type != last_type || current_type == E820_PRAM) {
 			if (last_type != 0)	 {
 				new_bios[new_bios_entry].size =
 					change_point[chgidx]->addr - last_addr;
@@ -688,6 +691,7 @@ void __init e820_mark_nosave_regions(unsigned long limit_pfn)
 			register_nosave_region(pfn, PFN_UP(ei->addr));
 
 		pfn = PFN_DOWN(ei->addr + ei->size);
+
 		if (ei->type != E820_RAM && ei->type != E820_RESERVED_KERN)
 			register_nosave_region(PFN_UP(ei->addr), pfn);
 
@@ -748,7 +752,7 @@ u64 __init early_reserve_e820(u64 size, u64 align)
 /*
  * Find the highest page frame number we have available
  */
-static unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
+static unsigned long __init e820_end_pfn(unsigned long limit_pfn)
 {
 	int i;
 	unsigned long last_pfn = 0;
@@ -759,7 +763,11 @@ static unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
 		unsigned long start_pfn;
 		unsigned long end_pfn;
 
-		if (ei->type != type)
+		/*
+		 * Persistent memory is accounted as ram for purposes of
+		 * establishing max_pfn and mem_map.
+		 */
+		if (ei->type != E820_RAM && ei->type != E820_PRAM)
 			continue;
 
 		start_pfn = ei->addr >> PAGE_SHIFT;
@@ -784,12 +792,12 @@ static unsigned long __init e820_end_pfn(unsigned long limit_pfn, unsigned type)
 }
 unsigned long __init e820_end_of_ram_pfn(void)
 {
-	return e820_end_pfn(MAX_ARCH_PFN, E820_RAM);
+	return e820_end_pfn(MAX_ARCH_PFN);
 }
 
 unsigned long __init e820_end_of_low_ram_pfn(void)
 {
-	return e820_end_pfn(1UL<<(32 - PAGE_SHIFT), E820_RAM);
+	return e820_end_pfn(1UL << (32-PAGE_SHIFT));
 }
 
 static void early_panic(char *msg)
@@ -866,6 +874,9 @@ static int __init parse_memmap_one(char *p)
 	} else if (*p == '$') {
 		start_at = memparse(p+1, &p);
 		e820_add_region(start_at, mem_size, E820_RESERVED);
+	} else if (*p == '!') {
+		start_at = memparse(p+1, &p);
+		e820_add_region(start_at, mem_size, E820_PRAM);
 	} else
 		e820_remove_range(mem_size, ULLONG_MAX - mem_size, E820_RAM, 1);
 
@@ -907,6 +918,7 @@ static inline const char *e820_type_to_string(int e820_type)
 	case E820_ACPI:	return "ACPI Tables";
 	case E820_NVS:	return "ACPI Non-volatile Storage";
 	case E820_UNUSABLE:	return "Unusable memory";
+	case E820_PRAM: return "Persistent RAM";
 	default:	return "reserved";
 	}
 }
@@ -940,7 +952,9 @@ void __init e820_reserve_resources(void)
 		 * pci device BAR resource and insert them later in
 		 * pcibios_resource_survey()
 		 */
-		if (e820.map[i].type != E820_RESERVED || res->start < (1ULL<<20)) {
+		if (((e820.map[i].type != E820_RESERVED) &&
+		     (e820.map[i].type != E820_PRAM)) ||
+		     res->start < (1ULL<<20)) {
 			res->flags |= IORESOURCE_BUSY;
 			insert_resource(&iomem_resource, res);
 		}