On Wed, 2017-05-03 at 17:25 -0600, Toshi Kani wrote:
On Wed, 2017-05-03 at 16:08 -0700, Dan Williams wrote:
> On Wed, May 3, 2017 at 3:51 PM, Dan Williams <dan.j.williams@intel.
> co
> m> wrote:
> > On Wed, May 3, 2017 at 3:41 PM, Kani, Toshimitsu <toshi.kani@hpe.
> > co
> > m> wrote:
> > > On Wed, 2017-05-03 at 14:48 -0700, Dan Williams wrote:
:
> >
> > I believe we already have all the data needed to calculate the
> > data
> > offset. Given the following sysfs path:
> >
> > /sys/devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/regio
> > n1
> > /dax1.1/dax/dax1.0
> >
> > ...we can find the associated namespace device from that dax1.1.
> > From
> > there we have the base address of the namespace and the size
> > device-dax instance.
> >
> > device_dax_data_offset == namespace_base + namespace_size -
> > device_dax_size
>
> Dave reminds me that we do have the data offset of the device-dax
> instance at the libnvdimm level:
>
> /sys/devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region1
> /d
> ax1.1/resource
>
> ...in this example, which maps to ndctl_dax_get_resource().
Thanks for the info! I noticed why I did not catch this info before.
# ll /dev/dax*
crw------- 1 root root 251, 3 May 3 04:28 /dev/dax0.0
# pwd
/sys/devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region0/dax0.
0
# grep . *
align:2097152
devtype:nd_dax
modalias:nd:t7
mode:none
numa_node:0
grep: power: Is a directory
grep: resource: No such device or address
grep: size: No such device or address
grep: subsystem: Is a directory
uevent:DEVTYPE=nd_dax
uevent:MODALIAS=nd:t7
But I noticed that "resource" and "size" that are under
".../region0/dax0.1" work. Is this intended?
Here is an output from dax0.1 (I removed the size value). Noticed that
mode is different.
# pwd
/sys/devices/LNXSYSTM:00/LNXSYBUS:00/ACPI0012:00/ndbus0/region0/dax0.1
# grep . *
align:2097152
grep: dax: Is a directory
grep: dax_region: Is a directory
devtype:nd_dax
grep: driver: Is a directory
modalias:nd:t7
mode:pmem
namespace:namespace0.0
numa_node:0
grep: power: Is a directory
resource:0x250200000
size:(size value)
grep: subsystem: Is a directory
uevent:DEVTYPE=nd_dax
uevent:DRIVER=dax_pmem
uevent:MODALIAS=nd:t7
uuid:8c71811f-260d-4788-8487-db88d829d393
Thanks,
-Toshi