From b1d99dc5f983b4ae8ab9841981c5dbd5530f6344 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Wed, 16 Jun 2021 06:38:48 -0700 Subject: [PATCH] iommu: Hook up '->unmap_pages' driver callback Extend iommu_pgsize() to populate an optional 'count' parameter so that we can direct unmapping operation to the ->unmap_pages callback if it has been provided by the driver. Signed-off-by: Will Deacon Signed-off-by: Isaac J. Manjarres Signed-off-by: Georgi Djakov Reviewed-by: Lu Baolu Link: https://lore.kernel.org/r/1623850736-389584-8-git-send-email-quic_c_gdjako@quicinc.com Signed-off-by: Joerg Roedel --- drivers/iommu/iommu.c | 59 ++++++++++++++++++++++++++++++++++++------- 1 file changed, 50 insertions(+), 9 deletions(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 80e14c139d40..725622c7e603 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -2376,11 +2376,11 @@ phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova) EXPORT_SYMBOL_GPL(iommu_iova_to_phys); static size_t iommu_pgsize(struct iommu_domain *domain, unsigned long iova, - phys_addr_t paddr, size_t size) + phys_addr_t paddr, size_t size, size_t *count) { - unsigned int pgsize_idx; + unsigned int pgsize_idx, pgsize_idx_next; unsigned long pgsizes; - size_t pgsize; + size_t offset, pgsize, pgsize_next; unsigned long addr_merge = paddr | iova; /* Page sizes supported by the hardware and small enough for @size */ @@ -2396,7 +2396,36 @@ static size_t iommu_pgsize(struct iommu_domain *domain, unsigned long iova, /* Pick the biggest page size remaining */ pgsize_idx = __fls(pgsizes); pgsize = BIT(pgsize_idx); + if (!count) + return pgsize; + /* Find the next biggest support page size, if it exists */ + pgsizes = domain->pgsize_bitmap & ~GENMASK(pgsize_idx, 0); + if (!pgsizes) + goto out_set_count; + + pgsize_idx_next = __ffs(pgsizes); + pgsize_next = BIT(pgsize_idx_next); + + /* + * There's no point trying a bigger page size unless the virtual + * and physical addresses are similarly offset within the larger page. + */ + if ((iova ^ paddr) & (pgsize_next - 1)) + goto out_set_count; + + /* Calculate the offset to the next page size alignment boundary */ + offset = pgsize_next - (addr_merge & (pgsize_next - 1)); + + /* + * If size is big enough to accommodate the larger page, reduce + * the number of smaller pages. + */ + if (offset + pgsize_next <= size) + size = offset; + +out_set_count: + *count = size >> pgsize_idx; return pgsize; } @@ -2434,7 +2463,7 @@ static int __iommu_map(struct iommu_domain *domain, unsigned long iova, pr_debug("map: iova 0x%lx pa %pa size 0x%zx\n", iova, &paddr, size); while (size) { - size_t pgsize = iommu_pgsize(domain, iova, paddr, size); + size_t pgsize = iommu_pgsize(domain, iova, paddr, size, NULL); pr_debug("mapping: iova 0x%lx pa %pa pgsize 0x%zx\n", iova, &paddr, pgsize); @@ -2485,6 +2514,19 @@ int iommu_map_atomic(struct iommu_domain *domain, unsigned long iova, } EXPORT_SYMBOL_GPL(iommu_map_atomic); +static size_t __iommu_unmap_pages(struct iommu_domain *domain, + unsigned long iova, size_t size, + struct iommu_iotlb_gather *iotlb_gather) +{ + const struct iommu_ops *ops = domain->ops; + size_t pgsize, count; + + pgsize = iommu_pgsize(domain, iova, iova, size, &count); + return ops->unmap_pages ? + ops->unmap_pages(domain, iova, pgsize, count, iotlb_gather) : + ops->unmap(domain, iova, pgsize, iotlb_gather); +} + static size_t __iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size, struct iommu_iotlb_gather *iotlb_gather) @@ -2494,7 +2536,7 @@ static size_t __iommu_unmap(struct iommu_domain *domain, unsigned long orig_iova = iova; unsigned int min_pagesz; - if (unlikely(ops->unmap == NULL || + if (unlikely(!(ops->unmap || ops->unmap_pages) || domain->pgsize_bitmap == 0UL)) return 0; @@ -2522,10 +2564,9 @@ static size_t __iommu_unmap(struct iommu_domain *domain, * or we hit an area that isn't mapped. */ while (unmapped < size) { - size_t pgsize; - - pgsize = iommu_pgsize(domain, iova, iova, size - unmapped); - unmapped_page = ops->unmap(domain, iova, pgsize, iotlb_gather); + unmapped_page = __iommu_unmap_pages(domain, iova, + size - unmapped, + iotlb_gather); if (!unmapped_page) break; -- 2.25.1