Commit afad94a9 authored by Robin Murphy's avatar Robin Murphy Committed by Joerg Roedel
Browse files

iommu: Improve map/unmap sanity checks 



The current checks for the __IOMMU_DOMAIN_PAGING capability seem a
bit stifled, since it is quite likely now that a non-paging domain
won't have a pgsize_bitmap and/or mapping ops, and thus get caught
by the earlier condition anyway. Swap them around to test the more
fundamental condition first, then we can reasonably also upgrade
the other to a WARN_ON, since if a driver does ever expose a paging
domain without the means to actually page, it's clearly very broken.

Signed-off-by: default avatarRobin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/524db1ec0139c964d26928a6a264945aa66d010c.1694525662.git.robin.murphy@arm.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent bd111e98

drivers/iommu/iommu.c

+5 −5
Original line number Diff line number Diff line
@@ -2519,12 +2519,12 @@ static int __iommu_map(struct iommu_domain *domain, unsigned long iova, 
	phys_addr_t orig_paddr = paddr;

	int ret = 0;



	if (unlikely(!ops->map_pages || domain->pgsize_bitmap == 0UL))

		return -ENODEV;



	if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))

		return -EINVAL;



	if (WARN_ON(!ops->map_pages || domain->pgsize_bitmap == 0UL))

		return -ENODEV;



	/* find out the minimum page size supported */

	min_pagesz = 1 << __ffs(domain->pgsize_bitmap);
@@ -2602,10 +2602,10 @@ static size_t __iommu_unmap(struct iommu_domain *domain, 
	unsigned long orig_iova = iova;

	unsigned int min_pagesz;



	if (unlikely(!ops->unmap_pages || domain->pgsize_bitmap == 0UL))

	if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))

		return 0;



	if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING)))

	if (WARN_ON(!ops->unmap_pages || domain->pgsize_bitmap == 0UL))

		return 0;



	/* find out the minimum page size supported */