From: Christoph Hellwig Date: Mon, 5 May 2025 07:01:40 +0000 (+0300) Subject: iommu: generalize the batched sync after map interface X-Git-Tag: v6.16-rc1~159^2~6 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5c87cffe2d3853cfae61e9373ee98a0409839178;p=thirdparty%2Flinux.git iommu: generalize the batched sync after map interface For the upcoming IOVA-based DMA API we want to batch the ops->iotlb_sync_map() call after mapping multiple IOVAs from dma-iommu without having a scatterlist. Improve the API. Add a wrapper for the map_sync as iommu_sync_map() so that callers don't need to poke into the methods directly. Formalize __iommu_map() into iommu_map_nosync() which requires the caller to call iommu_sync_map() after all maps are completed. Refactor the existing sanity checks from all the different layers into iommu_map_nosync(). Signed-off-by: Christoph Hellwig Acked-by: Will Deacon Tested-by: Jens Axboe Reviewed-by: Jason Gunthorpe Reviewed-by: Luis Chamberlain Signed-off-by: Leon Romanovsky Signed-off-by: Marek Szyprowski --- diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index c8033ca663777..3dc47f62d9ff1 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -2440,8 +2440,8 @@ out_set_count: return pgsize; } -static int __iommu_map(struct iommu_domain *domain, unsigned long iova, - phys_addr_t paddr, size_t size, int prot, gfp_t gfp) +int iommu_map_nosync(struct iommu_domain *domain, unsigned long iova, + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) { const struct iommu_domain_ops *ops = domain->ops; unsigned long orig_iova = iova; @@ -2450,12 +2450,19 @@ static int __iommu_map(struct iommu_domain *domain, unsigned long iova, phys_addr_t orig_paddr = paddr; int ret = 0; + might_sleep_if(gfpflags_allow_blocking(gfp)); + if (unlikely(!(domain->type & __IOMMU_DOMAIN_PAGING))) return -EINVAL; if (WARN_ON(!ops->map_pages || domain->pgsize_bitmap == 0UL)) return -ENODEV; + /* Discourage passing strange GFP flags */ + if (WARN_ON_ONCE(gfp & (__GFP_COMP | __GFP_DMA | __GFP_DMA32 | + __GFP_HIGHMEM))) + return -EINVAL; + /* find out the minimum page size supported */ min_pagesz = 1 << __ffs(domain->pgsize_bitmap); @@ -2503,31 +2510,27 @@ static int __iommu_map(struct iommu_domain *domain, unsigned long iova, return ret; } -int iommu_map(struct iommu_domain *domain, unsigned long iova, - phys_addr_t paddr, size_t size, int prot, gfp_t gfp) +int iommu_sync_map(struct iommu_domain *domain, unsigned long iova, size_t size) { const struct iommu_domain_ops *ops = domain->ops; - int ret; - - might_sleep_if(gfpflags_allow_blocking(gfp)); - /* Discourage passing strange GFP flags */ - if (WARN_ON_ONCE(gfp & (__GFP_COMP | __GFP_DMA | __GFP_DMA32 | - __GFP_HIGHMEM))) - return -EINVAL; + if (!ops->iotlb_sync_map) + return 0; + return ops->iotlb_sync_map(domain, iova, size); +} - ret = __iommu_map(domain, iova, paddr, size, prot, gfp); - if (ret == 0 && ops->iotlb_sync_map) { - ret = ops->iotlb_sync_map(domain, iova, size); - if (ret) - goto out_err; - } +int iommu_map(struct iommu_domain *domain, unsigned long iova, + phys_addr_t paddr, size_t size, int prot, gfp_t gfp) +{ + int ret; - return ret; + ret = iommu_map_nosync(domain, iova, paddr, size, prot, gfp); + if (ret) + return ret; -out_err: - /* undo mappings already done */ - iommu_unmap(domain, iova, size); + ret = iommu_sync_map(domain, iova, size); + if (ret) + iommu_unmap(domain, iova, size); return ret; } @@ -2627,26 +2630,17 @@ ssize_t iommu_map_sg(struct iommu_domain *domain, unsigned long iova, struct scatterlist *sg, unsigned int nents, int prot, gfp_t gfp) { - const struct iommu_domain_ops *ops = domain->ops; size_t len = 0, mapped = 0; phys_addr_t start; unsigned int i = 0; int ret; - might_sleep_if(gfpflags_allow_blocking(gfp)); - - /* Discourage passing strange GFP flags */ - if (WARN_ON_ONCE(gfp & (__GFP_COMP | __GFP_DMA | __GFP_DMA32 | - __GFP_HIGHMEM))) - return -EINVAL; - while (i <= nents) { phys_addr_t s_phys = sg_phys(sg); if (len && s_phys != start + len) { - ret = __iommu_map(domain, iova + mapped, start, + ret = iommu_map_nosync(domain, iova + mapped, start, len, prot, gfp); - if (ret) goto out_err; @@ -2669,11 +2663,10 @@ next: sg = sg_next(sg); } - if (ops->iotlb_sync_map) { - ret = ops->iotlb_sync_map(domain, iova, mapped); - if (ret) - goto out_err; - } + ret = iommu_sync_map(domain, iova, mapped); + if (ret) + goto out_err; + return mapped; out_err: diff --git a/include/linux/iommu.h b/include/linux/iommu.h index ccce8a751e2a5..ce472af8e9c39 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -872,6 +872,10 @@ extern struct iommu_domain *iommu_get_domain_for_dev(struct device *dev); extern struct iommu_domain *iommu_get_dma_domain(struct device *dev); extern int iommu_map(struct iommu_domain *domain, unsigned long iova, phys_addr_t paddr, size_t size, int prot, gfp_t gfp); +int iommu_map_nosync(struct iommu_domain *domain, unsigned long iova, + phys_addr_t paddr, size_t size, int prot, gfp_t gfp); +int iommu_sync_map(struct iommu_domain *domain, unsigned long iova, + size_t size); extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova, size_t size); extern size_t iommu_unmap_fast(struct iommu_domain *domain,