From: Robin Murphy Date: Tue, 12 Sep 2023 16:18:44 +0000 (+0100) Subject: iommu: Improve map/unmap sanity checks X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=afad94a93ef12887390d67aa9b6dd6be2657712f;p=linux.git 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: Robin Murphy Link: https://lore.kernel.org/r/524db1ec0139c964d26928a6a264945aa66d010c.1694525662.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel --- diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 865fa4f179a8f..b2d08e422942b 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -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 */