libnvdimm: Export max available extent (1e687220) · Commits · 戴 / test

The 'available_size' attribute showing the combined total of all unallocated space isn't always useful to know how large of a namespace a user may be able to allocate if the region is fragmented. This patch will export the largest extent of unallocated space that may be allocated to create a new namespace. Signed-off-by:

Keith Busch <keith.busch@intel.com> Reviewed-by:

Vishal Verma <vishal.l.verma@intel.com> Signed-off-by:

Dave Jiang <dave.jiang@intel.com>

drivers/nvdimm/region_devs.c

+16 −0

Original line number	Diff line number	Diff line
		@@ -434,6 +434,21 @@ static ssize_t available_size_show(struct device *dev,
		}
		static DEVICE_ATTR_RO(available_size);

		static ssize_t max_available_extent_show(struct device *dev,
		struct device_attribute attr, char buf)
		{
		struct nd_region *nd_region = to_nd_region(dev);
		unsigned long long available = 0;

		nvdimm_bus_lock(dev);
		wait_nvdimm_bus_probe_idle(dev);
		available = nd_region_allocatable_dpa(nd_region);
		nvdimm_bus_unlock(dev);

		return sprintf(buf, "%llu\n", available);
		}
		static DEVICE_ATTR_RO(max_available_extent);

		static ssize_t init_namespaces_show(struct device *dev,
		struct device_attribute attr, char buf)
		{
		@@ -585,6 +600,7 @@ static struct attribute *nd_region_attributes[] = {
		&dev_attr_read_only.attr,
		&dev_attr_set_cookie.attr,
		&dev_attr_available_size.attr,
		&dev_attr_max_available_extent.attr,
		&dev_attr_namespace_seed.attr,
		&dev_attr_init_namespaces.attr,
		&dev_attr_badblocks.attr,

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