| Message ID | 20190621004038.15180-1-vishal.l.verma@intel.com (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | 40cdc60ac16a42eb4e013f84d0e7aa1d6ee060d3 |
| Headers | show |
| Series | device-dax: Add a 'resource' attribute | expand |
On Thu, Jun 20, 2019 at 5:41 PM Vishal Verma <vishal.l.verma@intel.com> wrote: > > device-dax based devices were missing a 'resource' attribute to indicate > the physical address range contributed by the device in question. This > information is desirable to userspace tooling that may want to use the > dax device as system-ram, and wants to selectively hotplug and online > the memory blocks associated with a given device. > > Without this, the tooling would have to parse /proc/iomem for the memory > ranges contributed by dax devices, which can be a workaround, but it is > far easier to provide this information in the sysfs hierarchy. > > Cc: Dave Hansen <dave.hansen@linux.intel.com> > Cc: Dan Williams <dan.j.williams@intel.com> > Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Looks good to me, applied.
diff --git a/drivers/dax/bus.c b/drivers/dax/bus.c index 2109cfe80219..2f3c42ca416a 100644 --- a/drivers/dax/bus.c +++ b/drivers/dax/bus.c @@ -295,6 +295,22 @@ static ssize_t target_node_show(struct device *dev, } static DEVICE_ATTR_RO(target_node); +static unsigned long long dev_dax_resource(struct dev_dax *dev_dax) +{ + struct dax_region *dax_region = dev_dax->region; + + return dax_region->res.start; +} + +static ssize_t resource_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dev_dax *dev_dax = to_dev_dax(dev); + + return sprintf(buf, "%#llx\n", dev_dax_resource(dev_dax)); +} +static DEVICE_ATTR_RO(resource); + static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -313,6 +329,8 @@ static umode_t dev_dax_visible(struct kobject *kobj, struct attribute *a, int n) if (a == &dev_attr_target_node.attr && dev_dax_target_node(dev_dax) < 0) return 0; + if (a == &dev_attr_resource.attr) + return 0400; return a->mode; } @@ -320,6 +338,7 @@ static struct attribute *dev_dax_attributes[] = { &dev_attr_modalias.attr, &dev_attr_size.attr, &dev_attr_target_node.attr, + &dev_attr_resource.attr, NULL, };
device-dax based devices were missing a 'resource' attribute to indicate the physical address range contributed by the device in question. This information is desirable to userspace tooling that may want to use the dax device as system-ram, and wants to selectively hotplug and online the memory blocks associated with a given device. Without this, the tooling would have to parse /proc/iomem for the memory ranges contributed by dax devices, which can be a workaround, but it is far easier to provide this information in the sysfs hierarchy. Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> --- drivers/dax/bus.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)