diff options
| -rw-r--r-- | Documentation/kernel-parameters.txt | 6 | ||||
| -rw-r--r-- | MAINTAINERS | 6 | ||||
| -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 | ||||
| -rw-r--r-- | drivers/block/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/block/Makefile | 1 | ||||
| -rw-r--r-- | drivers/block/pmem.c | 262 |
10 files changed, 380 insertions, 6 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 5bc92d2..274252f 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1972,6 +1972,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. or memmap=0x10000$0x18690000 + memmap=nn[KMG]!ss[KMG] + [KNL,X86] Mark specific memory as protected. + Region of memory to be used, from ss to ss+nn. + The memory region may be marked as e820 type 12 (0xc) + and is NVDIMM or ADR memory. + memory_corruption_check=0/1 [X86] Some BIOSes seem to corrupt the first 64k of memory when doing things like suspend/resume. diff --git a/MAINTAINERS b/MAINTAINERS index dcd4346..db335f9 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -8130,6 +8130,12 @@ S: Maintained F: Documentation/blockdev/ramdisk.txt F: drivers/block/brd.c +PERSISTENT MEMORY DRIVER +M: Ross Zwisler <ross.zwisler@linux.intel.com> +L: linux-nvdimm@lists.01.org +S: Supported +F: drivers/block/pmem.c + RANDOM NUMBER DRIVER M: "Theodore Ts'o" <tytso@mit.edu> S: Maintained diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 937812b..6049d58 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 d993e33..960a8a9 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 c887cd9..9bcd0b5 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 7d46bb2..e2ce85d 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 0000000..3420c87 --- /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); diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig index 1b8094d..eb1fed5 100644 --- a/drivers/block/Kconfig +++ b/drivers/block/Kconfig @@ -404,6 +404,17 @@ config BLK_DEV_RAM_DAX and will prevent RAM block device backing store memory from being allocated from highmem (only a problem for highmem systems). +config BLK_DEV_PMEM + tristate "Persistent memory block device support" + help + Saying Y here will allow you to use a contiguous range of reserved + memory as one or more persistent block devices. + + To compile this driver as a module, choose M here: the module will be + called 'pmem'. + + If unsure, say N. + config CDROM_PKTCDVD tristate "Packet writing on CD/DVD media" depends on !UML diff --git a/drivers/block/Makefile b/drivers/block/Makefile index 02b688d..9cc6c18 100644 --- a/drivers/block/Makefile +++ b/drivers/block/Makefile @@ -14,6 +14,7 @@ obj-$(CONFIG_PS3_VRAM) += ps3vram.o obj-$(CONFIG_ATARI_FLOPPY) += ataflop.o obj-$(CONFIG_AMIGA_Z2RAM) += z2ram.o obj-$(CONFIG_BLK_DEV_RAM) += brd.o +obj-$(CONFIG_BLK_DEV_PMEM) += pmem.o obj-$(CONFIG_BLK_DEV_LOOP) += loop.o obj-$(CONFIG_BLK_CPQ_DA) += cpqarray.o obj-$(CONFIG_BLK_CPQ_CISS_DA) += cciss.o diff --git a/drivers/block/pmem.c b/drivers/block/pmem.c new file mode 100644 index 0000000..eabf4a8 --- /dev/null +++ b/drivers/block/pmem.c @@ -0,0 +1,262 @@ +/* + * Persistent Memory Driver + * + * Copyright (c) 2014, Intel Corporation. + * Copyright (c) 2015, Christoph Hellwig <hch@lst.de>. + * Copyright (c) 2015, Boaz Harrosh <boaz@plexistor.com>. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#include <asm/cacheflush.h> +#include <linux/blkdev.h> +#include <linux/hdreg.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/slab.h> + +#define PMEM_MINORS 16 + +struct pmem_device { + struct request_queue *pmem_queue; + struct gendisk *pmem_disk; + + /* One contiguous memory region per device */ + phys_addr_t phys_addr; + void *virt_addr; + size_t size; +}; + +static int pmem_major; +static atomic_t pmem_index; + +static void pmem_do_bvec(struct pmem_device *pmem, struct page *page, + unsigned int len, unsigned int off, int rw, + sector_t sector) +{ + void *mem = kmap_atomic(page); + size_t pmem_off = sector << 9; + + if (rw == READ) { + memcpy(mem + off, pmem->virt_addr + pmem_off, len); + flush_dcache_page(page); + } else { + flush_dcache_page(page); + memcpy(pmem->virt_addr + pmem_off, mem + off, len); + } + + kunmap_atomic(mem); +} + +static void pmem_make_request(struct request_queue *q, struct bio *bio) +{ + struct block_device *bdev = bio->bi_bdev; + struct pmem_device *pmem = bdev->bd_disk->private_data; + int rw; + struct bio_vec bvec; + sector_t sector; + struct bvec_iter iter; + int err = 0; + + if (bio_end_sector(bio) > get_capacity(bdev->bd_disk)) { + err = -EIO; + goto out; + } + + BUG_ON(bio->bi_rw & REQ_DISCARD); + + rw = bio_data_dir(bio); + sector = bio->bi_iter.bi_sector; + bio_for_each_segment(bvec, bio, iter) { + pmem_do_bvec(pmem, bvec.bv_page, bvec.bv_len, bvec.bv_offset, + rw, sector); + sector += bvec.bv_len >> 9; + } + +out: + bio_endio(bio, err); +} + +static int pmem_rw_page(struct block_device *bdev, sector_t sector, + struct page *page, int rw) +{ + struct pmem_device *pmem = bdev->bd_disk->private_data; + + pmem_do_bvec(pmem, page, PAGE_CACHE_SIZE, 0, rw, sector); + page_endio(page, rw & WRITE, 0); + + return 0; +} + +static long pmem_direct_access(struct block_device *bdev, sector_t sector, + void **kaddr, unsigned long *pfn, long size) +{ + struct pmem_device *pmem = bdev->bd_disk->private_data; + size_t offset = sector << 9; + + if (!pmem) + return -ENODEV; + + *kaddr = pmem->virt_addr + offset; + *pfn = (pmem->phys_addr + offset) >> PAGE_SHIFT; + + return pmem->size - offset; +} + +static const struct block_device_operations pmem_fops = { + .owner = THIS_MODULE, + .rw_page = pmem_rw_page, + .direct_access = pmem_direct_access, +}; + +static struct pmem_device *pmem_alloc(struct device *dev, struct resource *res) +{ + struct pmem_device *pmem; + struct gendisk *disk; + int idx, err; + + err = -ENOMEM; + pmem = kzalloc(sizeof(*pmem), GFP_KERNEL); + if (!pmem) + goto out; + + pmem->phys_addr = res->start; + pmem->size = resource_size(res); + + err = -EINVAL; + if (!request_mem_region(pmem->phys_addr, pmem->size, "pmem")) { + dev_warn(dev, "could not reserve region [0x%pa:0x%zx]\n", &pmem->phys_addr, pmem->size); + goto out_free_dev; + } + + /* + * Map the memory as non-cachable, as we can't write back the contents + * of the CPU caches in case of a crash. + */ + err = -ENOMEM; + pmem->virt_addr = ioremap_nocache(pmem->phys_addr, pmem->size); + if (!pmem->virt_addr) + goto out_release_region; + + pmem->pmem_queue = blk_alloc_queue(GFP_KERNEL); + if (!pmem->pmem_queue) + goto out_unmap; + + blk_queue_make_request(pmem->pmem_queue, pmem_make_request); + blk_queue_max_hw_sectors(pmem->pmem_queue, 1024); + blk_queue_bounce_limit(pmem->pmem_queue, BLK_BOUNCE_ANY); + + disk = alloc_disk(PMEM_MINORS); + if (!disk) + goto out_free_queue; + + idx = atomic_inc_return(&pmem_index) - 1; + + disk->major = pmem_major; + disk->first_minor = PMEM_MINORS * idx; + disk->fops = &pmem_fops; + disk->private_data = pmem; + disk->queue = pmem->pmem_queue; + disk->flags = GENHD_FL_EXT_DEVT; + sprintf(disk->disk_name, "pmem%d", idx); + disk->driverfs_dev = dev; + set_capacity(disk, pmem->size >> 9); + pmem->pmem_disk = disk; + + add_disk(disk); + + return pmem; + +out_free_queue: + blk_cleanup_queue(pmem->pmem_queue); +out_unmap: + iounmap(pmem->virt_addr); +out_release_region: + release_mem_region(pmem->phys_addr, pmem->size); +out_free_dev: + kfree(pmem); +out: + return ERR_PTR(err); +} + +static void pmem_free(struct pmem_device *pmem) +{ + del_gendisk(pmem->pmem_disk); + put_disk(pmem->pmem_disk); + blk_cleanup_queue(pmem->pmem_queue); + iounmap(pmem->virt_addr); + release_mem_region(pmem->phys_addr, pmem->size); + kfree(pmem); +} + +static int pmem_probe(struct platform_device *pdev) +{ + struct pmem_device *pmem; + struct resource *res; + + if (WARN_ON(pdev->num_resources > 1)) + return -ENXIO; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENXIO; + + pmem = pmem_alloc(&pdev->dev, res); + if (IS_ERR(pmem)) + return PTR_ERR(pmem); + + platform_set_drvdata(pdev, pmem); + + return 0; +} + +static int pmem_remove(struct platform_device *pdev) +{ + struct pmem_device *pmem = platform_get_drvdata(pdev); + + pmem_free(pmem); + return 0; +} + +static struct platform_driver pmem_driver = { + .probe = pmem_probe, + .remove = pmem_remove, + .driver = { + .owner = THIS_MODULE, + .name = "pmem", + }, +}; + +static int __init pmem_init(void) +{ + int error; + + pmem_major = register_blkdev(0, "pmem"); + if (pmem_major < 0) + return pmem_major; + + error = platform_driver_register(&pmem_driver); + if (error) + unregister_blkdev(pmem_major, "pmem"); + return error; +} +module_init(pmem_init); + +static void pmem_exit(void) +{ + platform_driver_unregister(&pmem_driver); + unregister_blkdev(pmem_major, "pmem"); +} +module_exit(pmem_exit); + +MODULE_AUTHOR("Ross Zwisler <ross.zwisler@linux.intel.com>"); +MODULE_LICENSE("GPL v2"); |
