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Commit 3d88002e authored by Dan Williams's avatar Dan Williams
Browse files

libnvdimm: support for legacy (non-aliasing) nvdimms 



The libnvdimm region driver is an intermediary driver that translates
non-volatile "region"s into "namespace" sub-devices that are surfaced by
persistent memory block-device drivers (PMEM and BLK).

ACPI 6 introduces the concept that a given nvdimm may simultaneously
offer multiple access modes to its media through direct PMEM load/store
access, or windowed BLK mode.  Existing nvdimms mostly implement a PMEM
interface, some offer a BLK-like mode, but never both as ACPI 6 defines.
If an nvdimm is single interfaced, then there is no need for dimm
metadata labels.  For these devices we can take the region boundaries
directly to create a child namespace device (nd_namespace_io).

Acked-by: default avatarChristoph Hellwig <hch@lst.de>
Tested-by: default avatarToshi Kani <toshi.kani@hp.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent 1f7df6f8

drivers/acpi/nfit.c

+1 −0
Original line number Diff line number Diff line
@@ -780,6 +780,7 @@ static struct attribute_group acpi_nfit_region_attribute_group = { 
static const struct attribute_group *acpi_nfit_region_attribute_groups[] = {

	&nd_region_attribute_group,

	&nd_mapping_attribute_group,

	&nd_device_attribute_group,

	&acpi_nfit_region_attribute_group,

	NULL,

};

drivers/nvdimm/Makefile

+2 −0
Original line number Diff line number Diff line
@@ -5,3 +5,5 @@ libnvdimm-y += bus.o 
libnvdimm-y += dimm_devs.o

libnvdimm-y += dimm.o

libnvdimm-y += region_devs.o

libnvdimm-y += region.o

libnvdimm-y += namespace_devs.o

drivers/nvdimm/bus.c

+26 −0
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ 
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/vmalloc.h>

#include <linux/uaccess.h>

#include <linux/module.h>

#include <linux/fcntl.h>

#include <linux/async.h>

#include <linux/ndctl.h>
@@ -33,6 +34,12 @@ static int to_nd_device_type(struct device *dev) 
{

	if (is_nvdimm(dev))

		return ND_DEVICE_DIMM;

	else if (is_nd_pmem(dev))

		return ND_DEVICE_REGION_PMEM;

	else if (is_nd_blk(dev))

		return ND_DEVICE_REGION_BLK;

	else if (is_nd_pmem(dev->parent) || is_nd_blk(dev->parent))

		return nd_region_to_nstype(to_nd_region(dev->parent));



	return 0;

}
@@ -50,27 +57,46 @@ static int nvdimm_bus_match(struct device *dev, struct device_driver *drv) 
	return test_bit(to_nd_device_type(dev), &nd_drv->type);

}



static struct module *to_bus_provider(struct device *dev)

{

	/* pin bus providers while regions are enabled */

	if (is_nd_pmem(dev) || is_nd_blk(dev)) {

		struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);



		return nvdimm_bus->module;

	}

	return NULL;

}



static int nvdimm_bus_probe(struct device *dev)

{

	struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);

	struct module *provider = to_bus_provider(dev);

	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);

	int rc;



	if (!try_module_get(provider))

		return -ENXIO;



	rc = nd_drv->probe(dev);

	dev_dbg(&nvdimm_bus->dev, "%s.probe(%s) = %d\n", dev->driver->name,

			dev_name(dev), rc);

	if (rc != 0)

		module_put(provider);

	return rc;

}



static int nvdimm_bus_remove(struct device *dev)

{

	struct nd_device_driver *nd_drv = to_nd_device_driver(dev->driver);

	struct module *provider = to_bus_provider(dev);

	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);

	int rc;



	rc = nd_drv->remove(dev);

	dev_dbg(&nvdimm_bus->dev, "%s.remove(%s) = %d\n", dev->driver->name,

			dev_name(dev), rc);

	module_put(provider);

	return rc;

}

drivers/nvdimm/core.c

+41 −3
Original line number Diff line number Diff line
@@ -24,6 +24,36 @@ LIST_HEAD(nvdimm_bus_list); 
DEFINE_MUTEX(nvdimm_bus_list_mutex);

static DEFINE_IDA(nd_ida);



void nvdimm_bus_lock(struct device *dev)

{

	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);



	if (!nvdimm_bus)

		return;

	mutex_lock(&nvdimm_bus->reconfig_mutex);

}

EXPORT_SYMBOL(nvdimm_bus_lock);



void nvdimm_bus_unlock(struct device *dev)

{

	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);



	if (!nvdimm_bus)

		return;

	mutex_unlock(&nvdimm_bus->reconfig_mutex);

}

EXPORT_SYMBOL(nvdimm_bus_unlock);



bool is_nvdimm_bus_locked(struct device *dev)

{

	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);



	if (!nvdimm_bus)

		return false;

	return mutex_is_locked(&nvdimm_bus->reconfig_mutex);

}

EXPORT_SYMBOL(is_nvdimm_bus_locked);



static void nvdimm_bus_release(struct device *dev)

{

	struct nvdimm_bus *nvdimm_bus;
@@ -135,8 +165,8 @@ struct attribute_group nvdimm_bus_attribute_group = { 
};

EXPORT_SYMBOL_GPL(nvdimm_bus_attribute_group);



struct nvdimm_bus *nvdimm_bus_register(struct device *parent,

		struct nvdimm_bus_descriptor *nd_desc)

struct nvdimm_bus *__nvdimm_bus_register(struct device *parent,

		struct nvdimm_bus_descriptor *nd_desc, struct module *module)

{

	struct nvdimm_bus *nvdimm_bus;

	int rc;
@@ -146,11 +176,13 @@ struct nvdimm_bus *nvdimm_bus_register(struct device *parent, 
		return NULL;

	INIT_LIST_HEAD(&nvdimm_bus->list);

	nvdimm_bus->id = ida_simple_get(&nd_ida, 0, 0, GFP_KERNEL);

	mutex_init(&nvdimm_bus->reconfig_mutex);

	if (nvdimm_bus->id < 0) {

		kfree(nvdimm_bus);

		return NULL;

	}

	nvdimm_bus->nd_desc = nd_desc;

	nvdimm_bus->module = module;

	nvdimm_bus->dev.parent = parent;

	nvdimm_bus->dev.release = nvdimm_bus_release;

	nvdimm_bus->dev.groups = nd_desc->attr_groups;
@@ -174,7 +206,7 @@ struct nvdimm_bus *nvdimm_bus_register(struct device *parent, 
	put_device(&nvdimm_bus->dev);

	return NULL;

}

EXPORT_SYMBOL_GPL(nvdimm_bus_register);

EXPORT_SYMBOL_GPL(__nvdimm_bus_register);



static int child_unregister(struct device *dev, void *data)

{
@@ -218,7 +250,12 @@ static __init int libnvdimm_init(void) 
	rc = nvdimm_init();

	if (rc)

		goto err_dimm;

	rc = nd_region_init();

	if (rc)

		goto err_region;

	return 0;

 err_region:

	nvdimm_exit();

 err_dimm:

	nvdimm_bus_exit();

	return rc;
@@ -227,6 +264,7 @@ static __init int libnvdimm_init(void) 
static __exit void libnvdimm_exit(void)

{

	WARN_ON(!list_empty(&nvdimm_bus_list));

	nd_region_exit();

	nvdimm_exit();

	nvdimm_bus_exit();

}

drivers/nvdimm/dimm.c

+1 −1
Original line number Diff line number Diff line
@@ -84,7 +84,7 @@ int __init nvdimm_init(void) 
	return nd_driver_register(&nvdimm_driver);

}



void __exit nvdimm_exit(void)

void nvdimm_exit(void)

{

	driver_unregister(&nvdimm_driver.drv);

}