libnvdimm, pfn, dax: limit namespace alignments to the supported set (f13d2b61) · Commits · 戴 / test

Now that we properly advertise the supported pte, pmd, and pud sizes, restrict the supported alignments that can be set on a namespace. This assumes that userspace was not previously relying on the ability to set odd alignments. At least ndctl only ever supported setting the namespace alignment to 4K, 2M, or 1G. Cc: Oliver O'Halloran <oohall@gmail.com> Signed-off-by:

Dan Williams <dan.j.williams@intel.com>

drivers/nvdimm/pfn_devs.c

+2 −21

Original line number	Diff line number	Diff line
		@@ -134,26 +134,6 @@ static const unsigned long *nd_pfn_supported_alignments(void)
		return data;
		}

		static ssize_t __align_store(struct nd_pfn nd_pfn, const char buf)
		{
		unsigned long val;
		int rc;

		rc = kstrtoul(buf, 0, &val);
		if (rc)
		return rc;

		if (!is_power_of_2(val) \|\| val < PAGE_SIZE \|\| val > SZ_1G)
		return -EINVAL;

		if (nd_pfn->dev.driver)
		return -EBUSY;
		else
		nd_pfn->align = val;

		return 0;
		}

		static ssize_t align_store(struct device *dev,
		struct device_attribute attr, const char buf, size_t len)
		{
		@@ -162,7 +142,8 @@ static ssize_t align_store(struct device *dev,

		device_lock(dev);
		nvdimm_bus_lock(dev);
		rc = __align_store(nd_pfn, buf);
		rc = nd_size_select_store(dev, buf, &nd_pfn->align,
		nd_pfn_supported_alignments());
		dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__,
		rc, buf, buf[len - 1] == '\n' ? "" : "\n");
		nvdimm_bus_unlock(dev);

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