libnvdimm, dax: autodetect support

For autodetecting a previously established dax configuration we need the
info block to indicate block-device vs device-dax mode, and we need to
have the default namespace probe hand-off the configuration to the
dax_pmem driver.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This commit is contained in:
Dan Williams 2016-05-18 14:50:12 -07:00
parent b354aba016
commit c5ed926864
5 changed files with 57 additions and 8 deletions

View File

@ -15,6 +15,7 @@
#include <linux/slab.h>
#include <linux/mm.h>
#include "nd-core.h"
#include "pfn.h"
#include "nd.h"
static void nd_dax_release(struct device *dev)
@ -97,3 +98,37 @@ struct device *nd_dax_create(struct nd_region *nd_region)
__nd_device_register(dev);
return dev;
}
int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns)
{
int rc;
struct nd_dax *nd_dax;
struct device *dax_dev;
struct nd_pfn *nd_pfn;
struct nd_pfn_sb *pfn_sb;
struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
if (ndns->force_raw)
return -ENODEV;
nvdimm_bus_lock(&ndns->dev);
nd_dax = nd_dax_alloc(nd_region);
nd_pfn = &nd_dax->nd_pfn;
dax_dev = nd_pfn_devinit(nd_pfn, ndns);
nvdimm_bus_unlock(&ndns->dev);
if (!dax_dev)
return -ENOMEM;
pfn_sb = devm_kzalloc(dev, sizeof(*pfn_sb), GFP_KERNEL);
nd_pfn->pfn_sb = pfn_sb;
rc = nd_pfn_validate(nd_pfn, DAX_SIG);
dev_dbg(dev, "%s: dax: %s\n", __func__,
rc == 0 ? dev_name(dax_dev) : "<none>");
if (rc < 0) {
__nd_detach_ndns(dax_dev, &nd_pfn->ndns);
put_device(dax_dev);
} else
__nd_device_register(dax_dev);
return rc;
}
EXPORT_SYMBOL(nd_dax_probe);

View File

@ -232,7 +232,7 @@ bool is_nd_pfn(struct device *dev);
struct device *nd_pfn_create(struct nd_region *nd_region);
struct device *nd_pfn_devinit(struct nd_pfn *nd_pfn,
struct nd_namespace_common *ndns);
int nd_pfn_validate(struct nd_pfn *nd_pfn);
int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig);
extern struct attribute_group nd_pfn_attribute_group;
#else
static inline int nd_pfn_probe(struct device *dev,
@ -251,7 +251,7 @@ static inline struct device *nd_pfn_create(struct nd_region *nd_region)
return NULL;
}
static inline int nd_pfn_validate(struct nd_pfn *nd_pfn)
static inline int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig)
{
return -ENODEV;
}
@ -259,9 +259,16 @@ static inline int nd_pfn_validate(struct nd_pfn *nd_pfn)
struct nd_dax *to_nd_dax(struct device *dev);
#if IS_ENABLED(CONFIG_NVDIMM_DAX)
int nd_dax_probe(struct device *dev, struct nd_namespace_common *ndns);
bool is_nd_dax(struct device *dev);
struct device *nd_dax_create(struct nd_region *nd_region);
#else
static inline int nd_dax_probe(struct device *dev,
struct nd_namespace_common *ndns)
{
return -ENODEV;
}
static inline bool is_nd_dax(struct device *dev)
{
return false;

View File

@ -19,6 +19,7 @@
#define PFN_SIG_LEN 16
#define PFN_SIG "NVDIMM_PFN_INFO\0"
#define DAX_SIG "NVDIMM_DAX_INFO\0"
struct nd_pfn_sb {
u8 signature[PFN_SIG_LEN];

View File

@ -360,7 +360,7 @@ struct device *nd_pfn_create(struct nd_region *nd_region)
return dev;
}
int nd_pfn_validate(struct nd_pfn *nd_pfn)
int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig)
{
u64 checksum, offset;
struct nd_namespace_io *nsio;
@ -377,7 +377,7 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn)
if (nvdimm_read_bytes(ndns, SZ_4K, pfn_sb, sizeof(*pfn_sb)))
return -ENXIO;
if (memcmp(pfn_sb->signature, PFN_SIG, PFN_SIG_LEN) != 0)
if (memcmp(pfn_sb->signature, sig, PFN_SIG_LEN) != 0)
return -ENODEV;
checksum = le64_to_cpu(pfn_sb->checksum);
@ -467,7 +467,7 @@ int nd_pfn_probe(struct device *dev, struct nd_namespace_common *ndns)
pfn_sb = devm_kzalloc(dev, sizeof(*pfn_sb), GFP_KERNEL);
nd_pfn = to_nd_pfn(pfn_dev);
nd_pfn->pfn_sb = pfn_sb;
rc = nd_pfn_validate(nd_pfn);
rc = nd_pfn_validate(nd_pfn, PFN_SIG);
dev_dbg(dev, "%s: pfn: %s\n", __func__,
rc == 0 ? dev_name(pfn_dev) : "<none>");
if (rc < 0) {
@ -552,6 +552,7 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn)
struct nd_pfn_sb *pfn_sb;
unsigned long npfns;
phys_addr_t offset;
const char *sig;
u64 checksum;
int rc;
@ -560,7 +561,11 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn)
return -ENOMEM;
nd_pfn->pfn_sb = pfn_sb;
rc = nd_pfn_validate(nd_pfn);
if (is_nd_dax(&nd_pfn->dev))
sig = DAX_SIG;
else
sig = PFN_SIG;
rc = nd_pfn_validate(nd_pfn, sig);
if (rc != -ENODEV)
return rc;
@ -628,7 +633,7 @@ static int nd_pfn_init(struct nd_pfn *nd_pfn)
pfn_sb->mode = cpu_to_le32(nd_pfn->mode);
pfn_sb->dataoff = cpu_to_le64(offset);
pfn_sb->npfns = cpu_to_le64(npfns);
memcpy(pfn_sb->signature, PFN_SIG, PFN_SIG_LEN);
memcpy(pfn_sb->signature, sig, PFN_SIG_LEN);
memcpy(pfn_sb->uuid, nd_pfn->uuid, 16);
memcpy(pfn_sb->parent_uuid, nd_dev_to_uuid(&ndns->dev), 16);
pfn_sb->version_major = cpu_to_le16(1);

View File

@ -320,7 +320,8 @@ static int nd_pmem_probe(struct device *dev)
return pmem_attach_disk(dev, ndns);
/* if we find a valid info-block we'll come back as that personality */
if (nd_btt_probe(dev, ndns) == 0 || nd_pfn_probe(dev, ndns) == 0)
if (nd_btt_probe(dev, ndns) == 0 || nd_pfn_probe(dev, ndns) == 0
|| nd_dax_probe(dev, ndns) == 0)
return -ENXIO;
/* ...otherwise we're just a raw pmem device */