linux/drivers/nvdimm/namespace_devs.c
Dan Williams 3d88002e4a 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>
2015-06-24 21:24:10 -04:00

112 lines
2.6 KiB
C

/*
* 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;
}