diff options
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/Kconfig | 10 | ||||
| -rw-r--r-- | arch/x86/include/uapi/asm/e820.h | 10 | ||||
| -rw-r--r-- | arch/x86/kernel/Makefile | 1 | ||||
| -rw-r--r-- | arch/x86/kernel/e820.c | 26 | ||||
| -rw-r--r-- | arch/x86/kernel/pmem.c | 53 |
5 files changed, 94 insertions, 6 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 937812b8e0b9..6049d587599e 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1421,6 +1421,16 @@ config ILLEGAL_POINTER_VALUE source "mm/Kconfig" +config X86_PMEM_LEGACY + bool "Support non-standard NVDIMMs and ADR protected memory" + help + Treat memory marked using the non-standard e820 type of 12 as used + by the Intel Sandy Bridge-EP reference BIOS as protected memory. + The kernel will offer these regions to the 'pmem' driver so + they can be used for persistent storage. + + Say Y if unsure. + config HIGHPTE bool "Allocate 3rd-level pagetables from highmem" depends on HIGHMEM diff --git a/arch/x86/include/uapi/asm/e820.h b/arch/x86/include/uapi/asm/e820.h index d993e33f5236..960a8a9dc4ab 100644 --- a/arch/x86/include/uapi/asm/e820.h +++ b/arch/x86/include/uapi/asm/e820.h @@ -33,6 +33,16 @@ #define E820_NVS 4 #define E820_UNUSABLE 5 +/* + * This is a non-standardized way to represent ADR or NVDIMM regions that + * persist over a reboot. The kernel will ignore their special capabilities + * unless the CONFIG_X86_PMEM_LEGACY=y option is set. + * + * ( Note that older platforms also used 6 for the same type of memory, + * but newer versions switched to 12 as 6 was assigned differently. Some + * time they will learn... ) + */ +#define E820_PRAM 12 /* * reserved RAM used by kernel itself diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index c887cd944f0c..9bcd0b56ca17 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -95,6 +95,7 @@ obj-$(CONFIG_KVM_GUEST) += kvm.o kvmclock.o obj-$(CONFIG_PARAVIRT) += paravirt.o paravirt_patch_$(BITS).o obj-$(CONFIG_PARAVIRT_SPINLOCKS)+= paravirt-spinlocks.o obj-$(CONFIG_PARAVIRT_CLOCK) += pvclock.o +obj-$(CONFIG_X86_PMEM_LEGACY) += pmem.o obj-$(CONFIG_PCSPKR_PLATFORM) += pcspeaker.o 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); } diff --git a/arch/x86/kernel/pmem.c b/arch/x86/kernel/pmem.c new file mode 100644 index 000000000000..3420c874ddc5 --- /dev/null +++ b/arch/x86/kernel/pmem.c @@ -0,0 +1,53 @@ +/* + * Copyright (c) 2015, Christoph Hellwig. + */ +#include <linux/memblock.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <asm/e820.h> +#include <asm/page_types.h> +#include <asm/setup.h> + +static __init void register_pmem_device(struct resource *res) +{ + struct platform_device *pdev; + int error; + + pdev = platform_device_alloc("pmem", PLATFORM_DEVID_AUTO); + if (!pdev) + return; + + error = platform_device_add_resources(pdev, res, 1); + if (error) + goto out_put_pdev; + + error = platform_device_add(pdev); + if (error) + goto out_put_pdev; + return; + +out_put_pdev: + dev_warn(&pdev->dev, "failed to add 'pmem' (persistent memory) device!\n"); + platform_device_put(pdev); +} + +static __init int register_pmem_devices(void) +{ + int i; + + for (i = 0; i < e820.nr_map; i++) { + struct e820entry *ei = &e820.map[i]; + + if (ei->type == E820_PRAM) { + struct resource res = { + .flags = IORESOURCE_MEM, + .start = ei->addr, + .end = ei->addr + ei->size - 1, + }; + register_pmem_device(&res); + } + } + + return 0; +} +device_initcall(register_pmem_devices); |