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: Christoph Hellwig <hch@lst.de>
Tested-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dan Williams 2015-05-31 15:02:11 -04:00
parent 1f7df6f88b
commit 3d88002e4a
13 changed files with 383 additions and 8 deletions

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@ -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,
};

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@ -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

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@ -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;
}

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@ -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();
}

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@ -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);
}

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@ -0,0 +1,111 @@
/*
* Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that 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 <linux/module.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/nd.h>
#include "nd.h"
static void namespace_io_release(struct device *dev)
{
struct nd_namespace_io *nsio = to_nd_namespace_io(dev);
kfree(nsio);
}
static struct device_type namespace_io_device_type = {
.name = "nd_namespace_io",
.release = namespace_io_release,
};
static ssize_t nstype_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region *nd_region = to_nd_region(dev->parent);
return sprintf(buf, "%d\n", nd_region_to_nstype(nd_region));
}
static DEVICE_ATTR_RO(nstype);
static struct attribute *nd_namespace_attributes[] = {
&dev_attr_nstype.attr,
NULL,
};
static struct attribute_group nd_namespace_attribute_group = {
.attrs = nd_namespace_attributes,
};
static const struct attribute_group *nd_namespace_attribute_groups[] = {
&nd_device_attribute_group,
&nd_namespace_attribute_group,
NULL,
};
static struct device **create_namespace_io(struct nd_region *nd_region)
{
struct nd_namespace_io *nsio;
struct device *dev, **devs;
struct resource *res;
nsio = kzalloc(sizeof(*nsio), GFP_KERNEL);
if (!nsio)
return NULL;
devs = kcalloc(2, sizeof(struct device *), GFP_KERNEL);
if (!devs) {
kfree(nsio);
return NULL;
}
dev = &nsio->dev;
dev->type = &namespace_io_device_type;
dev->parent = &nd_region->dev;
res = &nsio->res;
res->name = dev_name(&nd_region->dev);
res->flags = IORESOURCE_MEM;
res->start = nd_region->ndr_start;
res->end = res->start + nd_region->ndr_size - 1;
devs[0] = dev;
return devs;
}
int nd_region_register_namespaces(struct nd_region *nd_region, int *err)
{
struct device **devs = NULL;
int i;
*err = 0;
switch (nd_region_to_nstype(nd_region)) {
case ND_DEVICE_NAMESPACE_IO:
devs = create_namespace_io(nd_region);
break;
default:
break;
}
if (!devs)
return -ENODEV;
for (i = 0; devs[i]; i++) {
struct device *dev = devs[i];
dev_set_name(dev, "namespace%d.%d", nd_region->id, i);
dev->groups = nd_namespace_attribute_groups;
nd_device_register(dev);
}
kfree(devs);
return i;
}

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@ -21,9 +21,11 @@ extern int nvdimm_major;
struct nvdimm_bus {
struct nvdimm_bus_descriptor *nd_desc;
struct module *module;
struct list_head list;
struct device dev;
int id;
struct mutex reconfig_mutex;
};
struct nvdimm {
@ -34,6 +36,9 @@ struct nvdimm {
int id;
};
bool is_nvdimm(struct device *dev);
bool is_nd_blk(struct device *dev);
bool is_nd_pmem(struct device *dev);
struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev);
int __init nvdimm_bus_init(void);
void nvdimm_bus_exit(void);
@ -43,5 +48,4 @@ void nd_synchronize(void);
int nvdimm_bus_register_dimms(struct nvdimm_bus *nvdimm_bus);
int nvdimm_bus_register_regions(struct nvdimm_bus *nvdimm_bus);
int nd_match_dimm(struct device *dev, void *data);
bool is_nvdimm(struct device *dev);
#endif /* __ND_CORE_H__ */

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@ -23,6 +23,11 @@ struct nvdimm_drvdata {
void *data;
};
struct nd_region_namespaces {
int count;
int active;
};
struct nd_region {
struct device dev;
u16 ndr_mappings;
@ -41,7 +46,15 @@ enum nd_async_mode {
void nd_device_register(struct device *dev);
void nd_device_unregister(struct device *dev, enum nd_async_mode mode);
int __init nvdimm_init(void);
int __init nd_region_init(void);
void nvdimm_exit(void);
void nd_region_exit(void);
int nvdimm_init_nsarea(struct nvdimm_drvdata *ndd);
int nvdimm_init_config_data(struct nvdimm_drvdata *ndd);
struct nd_region *to_nd_region(struct device *dev);
int nd_region_to_nstype(struct nd_region *nd_region);
int nd_region_register_namespaces(struct nd_region *nd_region, int *err);
void nvdimm_bus_lock(struct device *dev);
void nvdimm_bus_unlock(struct device *dev);
bool is_nvdimm_bus_locked(struct device *dev);
#endif /* __ND_H__ */

93
drivers/nvdimm/region.c Normal file
View File

@ -0,0 +1,93 @@
/*
* Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that 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 <linux/module.h>
#include <linux/device.h>
#include <linux/nd.h>
#include "nd.h"
static int nd_region_probe(struct device *dev)
{
int err;
struct nd_region_namespaces *num_ns;
struct nd_region *nd_region = to_nd_region(dev);
int rc = nd_region_register_namespaces(nd_region, &err);
num_ns = devm_kzalloc(dev, sizeof(*num_ns), GFP_KERNEL);
if (!num_ns)
return -ENOMEM;
if (rc < 0)
return rc;
num_ns->active = rc;
num_ns->count = rc + err;
dev_set_drvdata(dev, num_ns);
if (err == 0)
return 0;
if (rc == err)
return -ENODEV;
/*
* Given multiple namespaces per region, we do not want to
* disable all the successfully registered peer namespaces upon
* a single registration failure. If userspace is missing a
* namespace that it expects it can disable/re-enable the region
* to retry discovery after correcting the failure.
* <regionX>/namespaces returns the current
* "<async-registered>/<total>" namespace count.
*/
dev_err(dev, "failed to register %d namespace%s, continuing...\n",
err, err == 1 ? "" : "s");
return 0;
}
static int child_unregister(struct device *dev, void *data)
{
nd_device_unregister(dev, ND_SYNC);
return 0;
}
static int nd_region_remove(struct device *dev)
{
/* flush attribute readers and disable */
nvdimm_bus_lock(dev);
dev_set_drvdata(dev, NULL);
nvdimm_bus_unlock(dev);
device_for_each_child(dev, NULL, child_unregister);
return 0;
}
static struct nd_device_driver nd_region_driver = {
.probe = nd_region_probe,
.remove = nd_region_remove,
.drv = {
.name = "nd_region",
},
.type = ND_DRIVER_REGION_BLK | ND_DRIVER_REGION_PMEM,
};
int __init nd_region_init(void)
{
return nd_driver_register(&nd_region_driver);
}
void nd_region_exit(void)
{
driver_unregister(&nd_region_driver.drv);
}
MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_PMEM);
MODULE_ALIAS_ND_DEVICE(ND_DEVICE_REGION_BLK);

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@ -47,11 +47,16 @@ static struct device_type nd_volatile_device_type = {
.release = nd_region_release,
};
static bool is_nd_pmem(struct device *dev)
bool is_nd_pmem(struct device *dev)
{
return dev ? dev->type == &nd_pmem_device_type : false;
}
bool is_nd_blk(struct device *dev)
{
return dev ? dev->type == &nd_blk_device_type : false;
}
struct nd_region *to_nd_region(struct device *dev)
{
struct nd_region *nd_region = container_of(dev, struct nd_region, dev);
@ -61,6 +66,37 @@ struct nd_region *to_nd_region(struct device *dev)
}
EXPORT_SYMBOL_GPL(to_nd_region);
/**
* nd_region_to_nstype() - region to an integer namespace type
* @nd_region: region-device to interrogate
*
* This is the 'nstype' attribute of a region as well, an input to the
* MODALIAS for namespace devices, and bit number for a nvdimm_bus to match
* namespace devices with namespace drivers.
*/
int nd_region_to_nstype(struct nd_region *nd_region)
{
if (is_nd_pmem(&nd_region->dev)) {
u16 i, alias;
for (i = 0, alias = 0; i < nd_region->ndr_mappings; i++) {
struct nd_mapping *nd_mapping = &nd_region->mapping[i];
struct nvdimm *nvdimm = nd_mapping->nvdimm;
if (nvdimm->flags & NDD_ALIASING)
alias++;
}
if (alias)
return ND_DEVICE_NAMESPACE_PMEM;
else
return ND_DEVICE_NAMESPACE_IO;
} else if (is_nd_blk(&nd_region->dev)) {
return ND_DEVICE_NAMESPACE_BLK;
}
return 0;
}
static ssize_t size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
@ -88,9 +124,37 @@ static ssize_t mappings_show(struct device *dev,
}
static DEVICE_ATTR_RO(mappings);
static ssize_t nstype_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region *nd_region = to_nd_region(dev);
return sprintf(buf, "%d\n", nd_region_to_nstype(nd_region));
}
static DEVICE_ATTR_RO(nstype);
static ssize_t init_namespaces_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region_namespaces *num_ns = dev_get_drvdata(dev);
ssize_t rc;
nvdimm_bus_lock(dev);
if (num_ns)
rc = sprintf(buf, "%d/%d\n", num_ns->active, num_ns->count);
else
rc = -ENXIO;
nvdimm_bus_unlock(dev);
return rc;
}
static DEVICE_ATTR_RO(init_namespaces);
static struct attribute *nd_region_attributes[] = {
&dev_attr_size.attr,
&dev_attr_nstype.attr,
&dev_attr_mappings.attr,
&dev_attr_init_namespaces.attr,
NULL,
};

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@ -71,8 +71,11 @@ struct nd_region_desc {
struct nvdimm_bus;
struct device;
struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
struct nvdimm_bus_descriptor *nfit_desc);
struct module;
struct nvdimm_bus *__nvdimm_bus_register(struct device *parent,
struct nvdimm_bus_descriptor *nfit_desc, struct module *module);
#define nvdimm_bus_register(parent, desc) \
__nvdimm_bus_register(parent, desc, THIS_MODULE)
void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus);
struct nvdimm_bus *to_nvdimm_bus(struct device *dev);
struct nvdimm *to_nvdimm(struct device *dev);

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@ -26,6 +26,16 @@ static inline struct nd_device_driver *to_nd_device_driver(
struct device_driver *drv)
{
return container_of(drv, struct nd_device_driver, drv);
};
struct nd_namespace_io {
struct device dev;
struct resource res;
};
static inline struct nd_namespace_io *to_nd_namespace_io(struct device *dev)
{
return container_of(dev, struct nd_namespace_io, dev);
}
#define MODULE_ALIAS_ND_DEVICE(type) \

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@ -177,8 +177,18 @@ static inline const char *nvdimm_cmd_name(unsigned cmd)
#define ND_DEVICE_DIMM 1 /* nd_dimm: container for "config data" */
#define ND_DEVICE_REGION_PMEM 2 /* nd_region: (parent of PMEM namespaces) */
#define ND_DEVICE_REGION_BLK 3 /* nd_region: (parent of BLK namespaces) */
#define ND_DEVICE_NAMESPACE_IO 4 /* legacy persistent memory */
#define ND_DEVICE_NAMESPACE_PMEM 5 /* PMEM namespace (may alias with BLK) */
#define ND_DEVICE_NAMESPACE_BLK 6 /* BLK namespace (may alias with PMEM) */
enum nd_driver_flags {
ND_DRIVER_DIMM = 1 << ND_DEVICE_DIMM,
ND_DRIVER_REGION_PMEM = 1 << ND_DEVICE_REGION_PMEM,
ND_DRIVER_REGION_BLK = 1 << ND_DEVICE_REGION_BLK,
ND_DRIVER_NAMESPACE_IO = 1 << ND_DEVICE_NAMESPACE_IO,
ND_DRIVER_NAMESPACE_PMEM = 1 << ND_DEVICE_NAMESPACE_PMEM,
ND_DRIVER_NAMESPACE_BLK = 1 << ND_DEVICE_NAMESPACE_BLK,
};
#endif /* __NDCTL_H__ */