[PATCH v3 2/6] iommu/dma: add support for non-strict mode
From: Zhen Lei <hidden>
Date: 2018-07-12 06:19:25
Also in:
linux-iommu, lkml
Subsystem:
iommu dma-api layer, iommu subsystem, the rest · Maintainers:
Robin Murphy, Joerg Roedel, Will Deacon, Linus Torvalds
1. Save the related domain pointer in struct iommu_dma_cookie, make iovad capable call domain->ops->flush_iotlb_all to flush TLB. 2. Add a new iommu capability: IOMMU_CAP_NON_STRICT, which used to indicate that the iommu domain support non-strict mode. 3. During the iommu domain initialization phase, call capable() to check whether it support non-strcit mode. If so, call init_iova_flush_queue to register iovad->flush_cb callback. 4. All unmap(contains iova-free) APIs will finally invoke __iommu_dma_unmap -->iommu_dma_free_iova. If the domain is non-strict, call queue_iova to put off iova freeing. Signed-off-by: Zhen Lei <redacted> --- drivers/iommu/dma-iommu.c | 25 +++++++++++++++++++++++++ include/linux/iommu.h | 7 +++++++ 2 files changed, 32 insertions(+)
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index ddcbbdb..9f0c77a 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c@@ -55,6 +55,7 @@ struct iommu_dma_cookie { }; struct list_head msi_page_list; spinlock_t msi_lock; + struct iommu_domain *domain_non_strict; }; static inline size_t cookie_msi_granule(struct iommu_dma_cookie *cookie)
@@ -257,6 +258,17 @@ static int iova_reserve_iommu_regions(struct device *dev, return ret; } +static void iommu_dma_flush_iotlb_all(struct iova_domain *iovad) +{ + struct iommu_dma_cookie *cookie; + struct iommu_domain *domain; + + cookie = container_of(iovad, struct iommu_dma_cookie, iovad); + domain = cookie->domain_non_strict; + + domain->ops->flush_iotlb_all(domain); +} + /** * iommu_dma_init_domain - Initialise a DMA mapping domain * @domain: IOMMU domain previously prepared by iommu_get_dma_cookie()
@@ -272,6 +284,7 @@ static int iova_reserve_iommu_regions(struct device *dev, int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, u64 size, struct device *dev) { + const struct iommu_ops *ops = domain->ops; struct iommu_dma_cookie *cookie = domain->iova_cookie; struct iova_domain *iovad = &cookie->iovad; unsigned long order, base_pfn, end_pfn;
@@ -308,6 +321,15 @@ int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, } init_iova_domain(iovad, 1UL << order, base_pfn); + + if ((ops->capable && ops->capable(IOMMU_CAP_NON_STRICT)) && + (IOMMU_DOMAIN_STRICT_MODE(domain) == IOMMU_NON_STRICT)) { + BUG_ON(!ops->flush_iotlb_all); + + cookie->domain_non_strict = domain; + init_iova_flush_queue(iovad, iommu_dma_flush_iotlb_all, NULL); + } + if (!dev) return 0;
@@ -390,6 +412,9 @@ static void iommu_dma_free_iova(struct iommu_dma_cookie *cookie, /* The MSI case is only ever cleaning up its most recent allocation */ if (cookie->type == IOMMU_DMA_MSI_COOKIE) cookie->msi_iova -= size; + else if (cookie->domain_non_strict) + queue_iova(iovad, iova_pfn(iovad, iova), + size >> iova_shift(iovad), 0); else free_iova_fast(iovad, iova_pfn(iovad, iova), size >> iova_shift(iovad));
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 19938ee..82ed979 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h@@ -86,6 +86,12 @@ struct iommu_domain_geometry { #define IOMMU_DOMAIN_DMA (__IOMMU_DOMAIN_PAGING | \ __IOMMU_DOMAIN_DMA_API) +#define IOMMU_STRICT 0 +#define IOMMU_NON_STRICT 1 +#define IOMMU_STRICT_MODE_MASK 1UL +#define IOMMU_DOMAIN_STRICT_MODE(domain) \ + (domain->type != IOMMU_DOMAIN_UNMANAGED) + struct iommu_domain { unsigned type; const struct iommu_ops *ops;
@@ -101,6 +107,7 @@ enum iommu_cap { transactions */ IOMMU_CAP_INTR_REMAP, /* IOMMU supports interrupt isolation */ IOMMU_CAP_NOEXEC, /* IOMMU_NOEXEC flag */ + IOMMU_CAP_NON_STRICT, /* IOMMU supports non-strict mode */ }; /*
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1.8.3