From 4a20ce0ff68eb6fc4b1e8f25139c93b312f21229 Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Thu, 4 May 2023 22:10:55 +0100 Subject: iommu: Add a capability for flush queue support Passing a special type to domain_alloc to indirectly query whether flush queues are a worthwhile optimisation with the given driver is a bit clunky, and looking increasingly anachronistic. Let's put that into an explicit capability instead. Signed-off-by: Robin Murphy Reviewed-by: Lu Baolu Tested-by: Jerry Snitselaar # amd, intel, smmu-v3 Reviewed-by: Jerry Snitselaar Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/f0086a93dbccb92622e1ace775846d81c1c4b174.1683233867.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel --- include/linux/iommu.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux/iommu.h') diff --git a/include/linux/iommu.h b/include/linux/iommu.h index e8c9a7da1060..1b7180d6edae 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -127,6 +127,11 @@ enum iommu_cap { * this device. */ IOMMU_CAP_ENFORCE_CACHE_COHERENCY, + /* + * IOMMU driver does not issue TLB maintenance during .unmap, so can + * usefully support the non-strict DMA flush queue. + */ + IOMMU_CAP_DEFERRED_FLUSH, }; /* These are the possible reserved region types */ -- cgit v1.2.3-59-g8ed1b From a4fdd976227240b06ced89b5df88a1a1f388f092 Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Thu, 4 May 2023 22:10:56 +0100 Subject: iommu: Use flush queue capability It remains really handy to have distinct DMA domain types within core code for the sake of default domain policy selection, but we can now hide that detail from drivers by using the new capability instead. Signed-off-by: Robin Murphy Tested-by: Jerry Snitselaar # amd, intel, smmu-v3 Reviewed-by: Jerry Snitselaar Reviewed-by: Jason Gunthorpe Link: https://lore.kernel.org/r/1c552d99e8ba452bdac48209fa74c0bdd52fd9d9.1683233867.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 1 - drivers/iommu/arm/arm-smmu/arm-smmu.c | 3 +-- drivers/iommu/dma-iommu.c | 3 ++- drivers/iommu/intel/iommu.c | 1 - drivers/iommu/iommu.c | 3 ++- include/linux/iommu.h | 1 + 6 files changed, 6 insertions(+), 6 deletions(-) (limited to 'include/linux/iommu.h') diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 6d65a7e81df4..1ed9c4ed5db9 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -2024,7 +2024,6 @@ static struct iommu_domain *arm_smmu_domain_alloc(unsigned type) if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA && - type != IOMMU_DOMAIN_DMA_FQ && type != IOMMU_DOMAIN_IDENTITY) return NULL; diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c index 7f4ee365912c..a86acd76c1df 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c @@ -856,8 +856,7 @@ static struct iommu_domain *arm_smmu_domain_alloc(unsigned type) struct arm_smmu_domain *smmu_domain; if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_IDENTITY) { - if (using_legacy_binding || - (type != IOMMU_DOMAIN_DMA && type != IOMMU_DOMAIN_DMA_FQ)) + if (using_legacy_binding || type != IOMMU_DOMAIN_DMA) return NULL; } /* diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 7a9f0b0bddbd..c4bdd2587daf 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -586,7 +586,8 @@ static int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, goto done_unlock; /* If the FQ fails we can simply fall back to strict mode */ - if (domain->type == IOMMU_DOMAIN_DMA_FQ && iommu_dma_init_fq(domain)) + if (domain->type == IOMMU_DOMAIN_DMA_FQ && + (!device_iommu_capable(dev, IOMMU_CAP_DEFERRED_FLUSH) || iommu_dma_init_fq(domain))) domain->type = IOMMU_DOMAIN_DMA; ret = iova_reserve_iommu_regions(dev, domain); diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index ff923298f8ed..8096273b034c 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4064,7 +4064,6 @@ static struct iommu_domain *intel_iommu_domain_alloc(unsigned type) case IOMMU_DOMAIN_BLOCKED: return &blocking_domain; case IOMMU_DOMAIN_DMA: - case IOMMU_DOMAIN_DMA_FQ: case IOMMU_DOMAIN_UNMANAGED: dmar_domain = alloc_domain(type); if (!dmar_domain) { diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index f1dcfa3f1a1b..7078bf4a8ec8 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -1980,11 +1980,12 @@ static struct iommu_domain *__iommu_domain_alloc(const struct bus_type *bus, unsigned type) { struct iommu_domain *domain; + unsigned int alloc_type = type & IOMMU_DOMAIN_ALLOC_FLAGS; if (bus == NULL || bus->iommu_ops == NULL) return NULL; - domain = bus->iommu_ops->domain_alloc(type); + domain = bus->iommu_ops->domain_alloc(alloc_type); if (!domain) return NULL; diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 1b7180d6edae..d31642596675 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -65,6 +65,7 @@ struct iommu_domain_geometry { #define __IOMMU_DOMAIN_SVA (1U << 4) /* Shared process address space */ +#define IOMMU_DOMAIN_ALLOC_FLAGS ~__IOMMU_DOMAIN_DMA_FQ /* * This are the possible domain-types * -- cgit v1.2.3-59-g8ed1b