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-rw-r--r--Documentation/kernel-parameters.txt6
-rw-r--r--MAINTAINERS6
-rw-r--r--arch/x86/Kconfig10
-rw-r--r--arch/x86/include/uapi/asm/e820.h10
-rw-r--r--arch/x86/kernel/Makefile1
-rw-r--r--arch/x86/kernel/e820.c26
-rw-r--r--arch/x86/kernel/pmem.c53
-rw-r--r--drivers/block/Kconfig11
-rw-r--r--drivers/block/Makefile1
-rw-r--r--drivers/block/pmem.c262
10 files changed, 380 insertions, 6 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 5bc92d2f4716..274252f205b7 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 dcd43465eae1..db335f98cad0 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 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);
diff --git a/drivers/block/Kconfig b/drivers/block/Kconfig
index 1b8094d4d7af..eb1fed5bd516 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 02b688d1438d..9cc6c18a1c7e 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 000000000000..eabf4a8d0085
--- /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");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-06 22:40:22 +0000