Commit 1cb8e85a authored by Nishanth Aravamudan's avatar Nishanth Aravamudan Committed by Benjamin Herrenschmidt
Browse files

powerpc/dma: Fix dma_iommu_dma_supported compare 



The table offset is in entries, each of which imply a dma address of
an IOMMU page.

Also, we should check the device can reach the whole IOMMU table.

Signed-off-by: default avatarMilton Miller <miltonm@bga.com>
Signed-off-by: default avatarNishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent dda804ad

arch/powerpc/kernel/dma-iommu.c

+11 −10
Original line number Diff line number Diff line
@@ -74,16 +74,17 @@ static int dma_iommu_dma_supported(struct device *dev, u64 mask) 
{

	struct iommu_table *tbl = get_iommu_table_base(dev);



	if (!tbl || tbl->it_offset > mask) {

		printk(KERN_INFO

		       "Warning: IOMMU offset too big for device mask\n");

		if (tbl)

			printk(KERN_INFO

			       "mask: 0x%08llx, table offset: 0x%08lx\n",

				mask, tbl->it_offset);

		else

			printk(KERN_INFO "mask: 0x%08llx, table unavailable\n",

				mask);

	if (!tbl) {

		dev_info(dev, "Warning: IOMMU dma not supported: mask 0x%08llx"

			", table unavailable\n", mask);

		return 0;

	}



	if ((tbl->it_offset + tbl->it_size) > (mask >> IOMMU_PAGE_SHIFT)) {

		dev_info(dev, "Warning: IOMMU window too big for device mask\n");

		dev_info(dev, "mask: 0x%08llx, table end: 0x%08lx\n",

				mask, (tbl->it_offset + tbl->it_size) <<

				IOMMU_PAGE_SHIFT);

		return 0;

	} else

		return 1;