diff options
Diffstat (limited to 'target/linux/layerscape/patches-5.4/811-kvm-0003-arm-arm64-KVM-drop-qman-mmio-cacheable-mapping-hack.patch')
| -rw-r--r-- | target/linux/layerscape/patches-5.4/811-kvm-0003-arm-arm64-KVM-drop-qman-mmio-cacheable-mapping-hack.patch | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/target/linux/layerscape/patches-5.4/811-kvm-0003-arm-arm64-KVM-drop-qman-mmio-cacheable-mapping-hack.patch b/target/linux/layerscape/patches-5.4/811-kvm-0003-arm-arm64-KVM-drop-qman-mmio-cacheable-mapping-hack.patch new file mode 100644 index 0000000000..8593714b3d --- /dev/null +++ b/target/linux/layerscape/patches-5.4/811-kvm-0003-arm-arm64-KVM-drop-qman-mmio-cacheable-mapping-hack.patch @@ -0,0 +1,132 @@ +From d637252f72998261c9d77c0be57317c73ad77f83 Mon Sep 17 00:00:00 2001 +From: Laurentiu Tudor <laurentiu.tudor@nxp.com> +Date: Tue, 26 Jul 2016 16:38:18 +0300 +Subject: [PATCH] arm/arm64: KVM: drop qman mmio cacheable mapping hack + +Instead of hardcoding checks for qman cacheable +mmio region physical addresses extract mapping +information from the user-space mapping. +The involves several steps; + - get access to a pte part of the user-space mapping + by using get_locked_pte() / pte_unmap_unlock() apis + - extract memtype (normal / device), shareability from + the pte + - convert to S2 translation bits in newly added + function stage1_to_stage2_pgprot() + - finish making the s2 translation with the obtained bits + +Another explored option was using vm_area_struct::vm_page_prot +which is set in vfio-mc mmap code to the correct page bits. +However, experiments show that these bits are later altered +in the generic mmap code (e.g. the shareability bit is always +set on arm64). +The only place where the original bits can still be found +is the user-space mapping, using the method described above. + +Signed-off-by: Laurentiu Tudor <laurentiu.tudor@nxp.com> +[Bharat - Fixed mem_type check issue] +[changed "ifdef ARM64" to CONFIG_ARM64] +Signed-off-by: Bharat Bhushan <Bharat.Bhushan@nxp.com> +[Ioana - added a sanity check for hugepages] +Signed-off-by: Ioana Ciornei <ioana.ciornei@nxp.com> +[Fixed format issues] +Signed-off-by: Diana Craciun <diana.craciun@nxp.com> +--- + virt/kvm/arm/mmu.c | 55 ++++++++++++++++++++++++++++++++++++++++++++++++++++-- + 1 file changed, 53 insertions(+), 2 deletions(-) + +--- a/virt/kvm/arm/mmu.c ++++ b/virt/kvm/arm/mmu.c +@@ -1375,6 +1375,30 @@ out: + return ret; + } + ++#ifdef CONFIG_ARM64 ++static pgprot_t stage1_to_stage2_pgprot(pgprot_t prot) ++{ ++ switch (pgprot_val(prot) & PTE_ATTRINDX_MASK) { ++ case PTE_ATTRINDX(MT_DEVICE_nGnRE): ++ case PTE_ATTRINDX(MT_DEVICE_nGnRnE): ++ case PTE_ATTRINDX(MT_DEVICE_GRE): ++ return PAGE_S2_DEVICE; ++ case PTE_ATTRINDX(MT_NORMAL_NC): ++ case PTE_ATTRINDX(MT_NORMAL): ++ return (pgprot_val(prot) & PTE_SHARED) ++ ? PAGE_S2 ++ : PAGE_S2_NS; ++ } ++ ++ return PAGE_S2_DEVICE; ++} ++#else ++static pgprot_t stage1_to_stage2_pgprot(pgprot_t prot) ++{ ++ return PAGE_S2_DEVICE; ++} ++#endif ++ + static bool transparent_hugepage_adjust(kvm_pfn_t *pfnp, phys_addr_t *ipap) + { + kvm_pfn_t pfn = *pfnp; +@@ -1719,8 +1743,23 @@ static int user_mem_abort(struct kvm_vcp + * 3 levels, i.e, PMD is not folded. + */ + if (vma_pagesize == PMD_SIZE || +- (vma_pagesize == PUD_SIZE && kvm_stage2_has_pmd(kvm))) ++ (vma_pagesize == PUD_SIZE && kvm_stage2_has_pmd(kvm))) { + gfn = (fault_ipa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT; ++ } else { ++ if (!is_vm_hugetlb_page(vma)) { ++ pte_t *pte; ++ spinlock_t *ptl; ++ pgprot_t prot; ++ ++ pte = get_locked_pte(current->mm, memslot->userspace_addr, &ptl); ++ prot = stage1_to_stage2_pgprot(__pgprot(pte_val(*pte))); ++ pte_unmap_unlock(pte, ptl); ++#ifdef CONFIG_ARM64 ++ if (pgprot_val(prot) == pgprot_val(PAGE_S2_NS)) ++ mem_type = PAGE_S2_NS; ++#endif ++ } ++ } + up_read(¤t->mm->mmap_sem); + + /* We need minimum second+third level pages */ +@@ -1749,6 +1788,11 @@ static int user_mem_abort(struct kvm_vcp + if (is_error_noslot_pfn(pfn)) + return -EFAULT; + ++#ifdef CONFIG_ARM64 ++ if (pgprot_val(mem_type) == pgprot_val(PAGE_S2_NS)) { ++ flags |= KVM_S2PTE_FLAG_IS_IOMAP; ++ } else ++#endif + if (kvm_is_device_pfn(pfn)) { + mem_type = PAGE_S2_DEVICE; + flags |= KVM_S2PTE_FLAG_IS_IOMAP; +@@ -2336,6 +2380,9 @@ int kvm_arch_prepare_memory_region(struc + gpa_t gpa = mem->guest_phys_addr + + (vm_start - mem->userspace_addr); + phys_addr_t pa; ++ pgprot_t prot; ++ pte_t *pte; ++ spinlock_t *ptl; + + pa = (phys_addr_t)vma->vm_pgoff << PAGE_SHIFT; + pa += vm_start - vma->vm_start; +@@ -2346,9 +2393,13 @@ int kvm_arch_prepare_memory_region(struc + goto out; + } + ++ pte = get_locked_pte(current->mm, mem->userspace_addr, &ptl); ++ prot = stage1_to_stage2_pgprot(__pgprot(pte_val(*pte))); ++ pte_unmap_unlock(pte, ptl); ++ + ret = kvm_phys_addr_ioremap(kvm, gpa, pa, + vm_end - vm_start, +- writable, PAGE_S2_DEVICE); ++ writable, prot); + if (ret) + break; + } |