From e79e68cf3973c06d05fbe5fe555f99a1c03028d5 Mon Sep 17 00:00:00 2001 From: Mostafa Saleh Date: Thu, 12 Dec 2024 18:04:20 +0000 Subject: [PATCH] BACKPORT: FROMLIST: KVM: arm64: iommu: Add hypercall for map_sg Add a new type struct kvm_iommu_sg, that describes a simple sglist, and a hypercall that can consume it while calling the map_pages ops. Link: https://lore.kernel.org/all/20241212180423.1578358-57-smostafa@google.com/ Bug: 357781595 Bug: 384432312 Change-Id: I16d7ab89fa84baf356f4f50980a839c08e526f0f Signed-off-by: Mostafa Saleh --- arch/arm64/include/asm/kvm_asm.h | 1 + arch/arm64/include/asm/kvm_host.h | 19 ++++++++ arch/arm64/kvm/hyp/include/nvhe/iommu.h | 2 + arch/arm64/kvm/hyp/nvhe/hyp-main.c | 14 ++++++ arch/arm64/kvm/hyp/nvhe/iommu/iommu.c | 58 +++++++++++++++++++++++++ arch/arm64/kvm/iommu.c | 34 +++++++++++++++ 6 files changed, 128 insertions(+) diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index 09850cf2b784..5872a47d9ac4 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -117,6 +117,7 @@ enum __kvm_host_smccc_func { __KVM_HOST_SMCCC_FUNC___pkvm_host_iommu_iova_to_phys, __KVM_HOST_SMCCC_FUNC___pkvm_host_hvc_pd, __KVM_HOST_SMCCC_FUNC___pkvm_ptdump, + __KVM_HOST_SMCCC_FUNC___pkvm_host_iommu_map_sg, /* * Start of the dynamically registered hypercalls. Start a bit diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 519ac79305cf..a724dc5e49b8 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -1688,4 +1688,23 @@ void kvm_iommu_remove_driver(void); int pkvm_iommu_suspend(struct device *dev); int pkvm_iommu_resume(struct device *dev); +struct kvm_iommu_sg { + phys_addr_t phys; + size_t pgsize; + unsigned int pgcount; +}; + +static inline struct kvm_iommu_sg *kvm_iommu_sg_alloc(unsigned int nents, gfp_t gfp) +{ + return alloc_pages_exact(PAGE_ALIGN(nents * sizeof(struct kvm_iommu_sg)), gfp); +} + +static inline void kvm_iommu_sg_free(struct kvm_iommu_sg *sg, unsigned int nents) +{ + free_pages_exact(sg, PAGE_ALIGN(nents * sizeof(struct kvm_iommu_sg))); +} + +int kvm_iommu_share_hyp_sg(struct kvm_iommu_sg *sg, unsigned int nents); +int kvm_iommu_unshare_hyp_sg(struct kvm_iommu_sg *sg, unsigned int nents); + #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kvm/hyp/include/nvhe/iommu.h b/arch/arm64/kvm/hyp/include/nvhe/iommu.h index fc02ab6fa26d..7d939c2ac894 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/iommu.h +++ b/arch/arm64/kvm/hyp/include/nvhe/iommu.h @@ -27,6 +27,8 @@ size_t kvm_iommu_unmap_pages(pkvm_handle_t domain_id, unsigned long iova, size_t pgsize, size_t pgcount); phys_addr_t kvm_iommu_iova_to_phys(pkvm_handle_t domain_id, unsigned long iova); bool kvm_iommu_host_dabt_handler(struct kvm_cpu_context *host_ctxt, u64 esr, u64 addr); +size_t kvm_iommu_map_sg(pkvm_handle_t domain, unsigned long iova, struct kvm_iommu_sg *sg, + unsigned int nent, unsigned int prot); /* Flags for memory allocation for IOMMU drivers */ #define IOMMU_PAGE_NOCACHE BIT(0) diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c index cd2b999c14aa..d3aa10bcaedb 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -1710,6 +1710,19 @@ static void handle___pkvm_ptdump(struct kvm_cpu_context *host_ctxt) cpu_reg(host_ctxt, 0) = SMCCC_RET_NOT_SUPPORTED; } +static void handle___pkvm_host_iommu_map_sg(struct kvm_cpu_context *host_ctxt) +{ + unsigned long ret; + DECLARE_REG(pkvm_handle_t, domain, host_ctxt, 1); + DECLARE_REG(unsigned long, iova, host_ctxt, 2); + DECLARE_REG(struct kvm_iommu_sg *, sg, host_ctxt, 3); + DECLARE_REG(unsigned int, nent, host_ctxt, 4); + DECLARE_REG(unsigned int, prot, host_ctxt, 5); + + ret = kvm_iommu_map_sg(domain, iova, kern_hyp_va(sg), nent, prot); + hyp_reqs_smccc_encode(ret, host_ctxt, this_cpu_ptr(&host_hyp_reqs)); +} + typedef void (*hcall_t)(struct kvm_cpu_context *); #define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x @@ -1777,6 +1790,7 @@ static const hcall_t host_hcall[] = { HANDLE_FUNC(__pkvm_host_iommu_iova_to_phys), HANDLE_FUNC(__pkvm_host_hvc_pd), HANDLE_FUNC(__pkvm_ptdump), + HANDLE_FUNC(__pkvm_host_iommu_map_sg), }; static void handle_host_hcall(struct kvm_cpu_context *host_ctxt) diff --git a/arch/arm64/kvm/hyp/nvhe/iommu/iommu.c b/arch/arm64/kvm/hyp/nvhe/iommu/iommu.c index 3c21b5b7cb4d..4462ddf14de0 100644 --- a/arch/arm64/kvm/hyp/nvhe/iommu/iommu.c +++ b/arch/arm64/kvm/hyp/nvhe/iommu/iommu.c @@ -455,6 +455,64 @@ bool kvm_iommu_host_dabt_handler(struct kvm_cpu_context *host_ctxt, u64 esr, u64 return ret; } +size_t kvm_iommu_map_sg(pkvm_handle_t domain_id, unsigned long iova, struct kvm_iommu_sg *sg, + unsigned int nent, unsigned int prot) +{ + int ret; + size_t total_mapped = 0, mapped; + struct kvm_hyp_iommu_domain *domain; + phys_addr_t phys; + size_t size, pgsize, pgcount; + unsigned int orig_nent = nent; + struct kvm_iommu_sg *orig_sg = sg; + + if (!kvm_iommu_ops || !kvm_iommu_ops->map_pages) + return 0; + + if (prot & ~IOMMU_PROT_MASK) + return 0; + + domain = handle_to_domain(domain_id); + if (!domain || domain_get(domain)) + return 0; + + ret = hyp_pin_shared_mem(sg, sg + nent); + if (ret) + goto out_put_domain; + + while (nent--) { + phys = sg->phys; + pgsize = sg->pgsize; + pgcount = sg->pgcount; + + if (__builtin_mul_overflow(pgsize, pgcount, &size) || + iova + size < iova) + goto out_unpin_sg; + + ret = __pkvm_host_use_dma(phys, size); + if (ret) + goto out_unpin_sg; + + mapped = 0; + kvm_iommu_ops->map_pages(domain, iova, phys, pgsize, pgcount, prot, &mapped); + total_mapped += mapped; + phys += mapped; + iova += mapped; + /* Might need memory */ + if (mapped != size) { + __pkvm_host_unuse_dma(phys, size - mapped); + break; + } + sg++; + } + +out_unpin_sg: + hyp_unpin_shared_mem(orig_sg, orig_sg + orig_nent); +out_put_domain: + domain_put(domain); + return total_mapped; +} + static int iommu_power_on(struct kvm_power_domain *pd) { struct kvm_hyp_iommu *iommu = container_of(pd, struct kvm_hyp_iommu, diff --git a/arch/arm64/kvm/iommu.c b/arch/arm64/kvm/iommu.c index 5bc3e3fae983..1686e04cc342 100644 --- a/arch/arm64/kvm/iommu.c +++ b/arch/arm64/kvm/iommu.c @@ -82,3 +82,37 @@ int pkvm_iommu_resume(struct device *dev) return kvm_call_hyp_nvhe(__pkvm_host_hvc_pd, device_id, 1); } EXPORT_SYMBOL(pkvm_iommu_resume); + +int kvm_iommu_share_hyp_sg(struct kvm_iommu_sg *sg, unsigned int nents) +{ + size_t nr_pages = PAGE_ALIGN(sizeof(*sg) * nents) >> PAGE_SHIFT; + phys_addr_t sg_pfn = virt_to_phys(sg) >> PAGE_SHIFT; + int i; + int ret; + + for (i = 0 ; i < nr_pages ; ++i) { + ret = kvm_call_hyp_nvhe(__pkvm_host_share_hyp, sg_pfn + i); + if (ret) + return ret; + } + + return 0; +} +EXPORT_SYMBOL(kvm_iommu_share_hyp_sg); + +int kvm_iommu_unshare_hyp_sg(struct kvm_iommu_sg *sg, unsigned int nents) +{ + size_t nr_pages = PAGE_ALIGN(sizeof(*sg) * nents) >> PAGE_SHIFT; + phys_addr_t sg_pfn = virt_to_phys(sg) >> PAGE_SHIFT; + int i; + int ret; + + for (i = 0 ; i < nr_pages ; ++i) { + ret = kvm_call_hyp_nvhe(__pkvm_host_unshare_hyp, sg_pfn + i); + if (ret) + return ret; + } + + return 0; +} +EXPORT_SYMBOL(kvm_iommu_unshare_hyp_sg);