[PATCH v7 10/16] libnvdimm, pmem: add libnvdimm support to the pmem driver
From: Dan Williams
Date: Wed Jun 17 2015 - 19:17:08 EST
nd_pmem attaches to persistent memory regions and namespaces emitted by
the libnvdimm subsystem, and, same as the original pmem driver, presents
the system-physical-address range as a block device.
The existing e820-type-12 to pmem setup is converted to an nvdimm_bus
that emits an nd_namespace_io device.
Note that the X in 'pmemX' is now derived from the parent region. This
provides some stability to the pmem devices names from boot-to-boot.
The minor numbers are also more predictable by passing 0 to
alloc_disk().
Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx>
Cc: Boaz Harrosh <boaz@xxxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Ross Zwisler <ross.zwisler@xxxxxxxxxxxxxxx>
Acked-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
arch/x86/Kconfig | 3 ++
arch/x86/kernel/pmem.c | 92 +++++++++++++++++++++++++++++++-----------------
drivers/nvdimm/pmem.c | 68 +++++++++++++++++------------------
3 files changed, 96 insertions(+), 67 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 226d5696e1d1..1a2cbf641667 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1424,6 +1424,9 @@ source "mm/Kconfig"
config X86_PMEM_LEGACY
bool "Support non-standard NVDIMMs and ADR protected memory"
+ depends on PHYS_ADDR_T_64BIT
+ depends on BLK_DEV
+ select LIBNVDIMM
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.
diff --git a/arch/x86/kernel/pmem.c b/arch/x86/kernel/pmem.c
index 3420c874ddc5..0f4ef472ab9e 100644
--- a/arch/x86/kernel/pmem.c
+++ b/arch/x86/kernel/pmem.c
@@ -1,53 +1,81 @@
/*
* Copyright (c) 2015, Christoph Hellwig.
+ * Copyright (c) 2015, Intel Corporation.
*/
-#include <linux/memblock.h>
#include <linux/platform_device.h>
-#include <linux/slab.h>
+#include <linux/libnvdimm.h>
+#include <linux/module.h>
#include <asm/e820.h>
-#include <asm/page_types.h>
-#include <asm/setup.h>
-static __init void register_pmem_device(struct resource *res)
+static void e820_pmem_release(struct device *dev)
{
- struct platform_device *pdev;
- int error;
+ struct nvdimm_bus *nvdimm_bus = dev->platform_data;
- pdev = platform_device_alloc("pmem", PLATFORM_DEVID_AUTO);
- if (!pdev)
- return;
+ if (nvdimm_bus)
+ nvdimm_bus_unregister(nvdimm_bus);
+}
- error = platform_device_add_resources(pdev, res, 1);
- if (error)
- goto out_put_pdev;
+static struct platform_device e820_pmem = {
+ .name = "e820_pmem",
+ .id = -1,
+ .dev = {
+ .release = e820_pmem_release,
+ },
+};
- error = platform_device_add(pdev);
- if (error)
- goto out_put_pdev;
- return;
+static const struct attribute_group *e820_pmem_attribute_groups[] = {
+ &nvdimm_bus_attribute_group,
+ NULL,
+};
-out_put_pdev:
- dev_warn(&pdev->dev, "failed to add 'pmem' (persistent memory) device!\n");
- platform_device_put(pdev);
-}
+static const struct attribute_group *e820_pmem_region_attribute_groups[] = {
+ &nd_region_attribute_group,
+ &nd_device_attribute_group,
+ NULL,
+};
-static __init int register_pmem_devices(void)
+static __init int register_e820_pmem(void)
{
- int i;
+ static struct nvdimm_bus_descriptor nd_desc;
+ struct device *dev = &e820_pmem.dev;
+ struct nvdimm_bus *nvdimm_bus;
+ int rc, i;
+
+ rc = platform_device_register(&e820_pmem);
+ if (rc)
+ return rc;
+
+ nd_desc.attr_groups = e820_pmem_attribute_groups;
+ nd_desc.provider_name = "e820";
+ nvdimm_bus = nvdimm_bus_register(dev, &nd_desc);
+ if (!nvdimm_bus)
+ goto err;
+ dev->platform_data = nvdimm_bus;
for (i = 0; i < e820.nr_map; i++) {
struct e820entry *ei = &e820.map[i];
+ struct resource res = {
+ .flags = IORESOURCE_MEM,
+ .start = ei->addr,
+ .end = ei->addr + ei->size - 1,
+ };
+ struct nd_region_desc ndr_desc;
+
+ if (ei->type != E820_PRAM)
+ continue;
- if (ei->type == E820_PRAM) {
- struct resource res = {
- .flags = IORESOURCE_MEM,
- .start = ei->addr,
- .end = ei->addr + ei->size - 1,
- };
- register_pmem_device(&res);
- }
+ memset(&ndr_desc, 0, sizeof(ndr_desc));
+ ndr_desc.res = &res;
+ ndr_desc.attr_groups = e820_pmem_region_attribute_groups;
+ if (!nvdimm_pmem_region_create(nvdimm_bus, &ndr_desc))
+ goto err;
}
return 0;
+
+ err:
+ dev_err(dev, "failed to register legacy persistent memory ranges\n");
+ platform_device_unregister(&e820_pmem);
+ return -ENXIO;
}
-device_initcall(register_pmem_devices);
+device_initcall(register_e820_pmem);
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index eabf4a8d0085..d46975ed9e40 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -1,7 +1,7 @@
/*
* Persistent Memory Driver
*
- * Copyright (c) 2014, Intel Corporation.
+ * Copyright (c) 2014-2015, Intel Corporation.
* Copyright (c) 2015, Christoph Hellwig <hch@xxxxxx>.
* Copyright (c) 2015, Boaz Harrosh <boaz@xxxxxxxxxxxxx>.
*
@@ -23,8 +23,8 @@
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/slab.h>
-
-#define PMEM_MINORS 16
+#include <linux/nd.h>
+#include "nd.h"
struct pmem_device {
struct request_queue *pmem_queue;
@@ -37,7 +37,6 @@ struct pmem_device {
};
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,
@@ -118,11 +117,12 @@ static const struct block_device_operations pmem_fops = {
.direct_access = pmem_direct_access,
};
-static struct pmem_device *pmem_alloc(struct device *dev, struct resource *res)
+static struct pmem_device *pmem_alloc(struct device *dev,
+ struct resource *res, int id)
{
struct pmem_device *pmem;
struct gendisk *disk;
- int idx, err;
+ int err;
err = -ENOMEM;
pmem = kzalloc(sizeof(*pmem), GFP_KERNEL);
@@ -134,7 +134,8 @@ static struct pmem_device *pmem_alloc(struct device *dev, struct resource *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);
+ dev_warn(dev, "could not reserve region [0x%pa:0x%zx]\n",
+ &pmem->phys_addr, pmem->size);
goto out_free_dev;
}
@@ -155,19 +156,17 @@ static struct pmem_device *pmem_alloc(struct device *dev, struct resource *res)
blk_queue_max_hw_sectors(pmem->pmem_queue, 1024);
blk_queue_bounce_limit(pmem->pmem_queue, BLK_BOUNCE_ANY);
- disk = alloc_disk(PMEM_MINORS);
+ disk = alloc_disk(0);
if (!disk)
goto out_free_queue;
- idx = atomic_inc_return(&pmem_index) - 1;
-
disk->major = pmem_major;
- disk->first_minor = PMEM_MINORS * idx;
+ disk->first_minor = 0;
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);
+ sprintf(disk->disk_name, "pmem%d", id);
disk->driverfs_dev = dev;
set_capacity(disk, pmem->size >> 9);
pmem->pmem_disk = disk;
@@ -198,42 +197,38 @@ static void pmem_free(struct pmem_device *pmem)
kfree(pmem);
}
-static int pmem_probe(struct platform_device *pdev)
+static int nd_pmem_probe(struct device *dev)
{
+ struct nd_region *nd_region = to_nd_region(dev->parent);
+ struct nd_namespace_io *nsio = to_nd_namespace_io(dev);
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);
+ pmem = pmem_alloc(dev, &nsio->res, nd_region->id);
if (IS_ERR(pmem))
return PTR_ERR(pmem);
- platform_set_drvdata(pdev, pmem);
+ dev_set_drvdata(dev, pmem);
return 0;
}
-static int pmem_remove(struct platform_device *pdev)
+static int nd_pmem_remove(struct device *dev)
{
- struct pmem_device *pmem = platform_get_drvdata(pdev);
+ struct pmem_device *pmem = dev_get_drvdata(dev);
pmem_free(pmem);
return 0;
}
-static struct platform_driver pmem_driver = {
- .probe = pmem_probe,
- .remove = pmem_remove,
- .driver = {
- .owner = THIS_MODULE,
- .name = "pmem",
+MODULE_ALIAS("pmem");
+MODULE_ALIAS_ND_DEVICE(ND_DEVICE_NAMESPACE_IO);
+static struct nd_device_driver nd_pmem_driver = {
+ .probe = nd_pmem_probe,
+ .remove = nd_pmem_remove,
+ .drv = {
+ .name = "nd_pmem",
},
+ .type = ND_DRIVER_NAMESPACE_IO,
};
static int __init pmem_init(void)
@@ -244,16 +239,19 @@ static int __init pmem_init(void)
if (pmem_major < 0)
return pmem_major;
- error = platform_driver_register(&pmem_driver);
- if (error)
+ error = nd_driver_register(&nd_pmem_driver);
+ if (error) {
unregister_blkdev(pmem_major, "pmem");
- return error;
+ return error;
+ }
+
+ return 0;
}
module_init(pmem_init);
static void pmem_exit(void)
{
- platform_driver_unregister(&pmem_driver);
+ driver_unregister(&nd_pmem_driver.drv);
unregister_blkdev(pmem_major, "pmem");
}
module_exit(pmem_exit);
--
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