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

View File

@@ -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,
};