KVM: arm64: Convert user_mem_abort() to generic page-table API (6f745f1b) · Commits · 戴 / test

arch/arm64/kvm/mmu.c

+44 −80

Original line number	Diff line number	Diff line
		@@ -1499,18 +1499,19 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
		{
		int ret;
		bool write_fault, writable, force_pte = false;
		bool exec_fault, needs_exec;
		bool exec_fault;
		bool device = false;
		unsigned long mmu_seq;
		gfn_t gfn = fault_ipa >> PAGE_SHIFT;
		struct kvm *kvm = vcpu->kvm;
		struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache;
		struct vm_area_struct *vma;
		short vma_shift;
		gfn_t gfn;
		kvm_pfn_t pfn;
		pgprot_t mem_type = PAGE_S2;
		bool logging_active = memslot_is_logging(memslot);
		unsigned long vma_pagesize, flags = 0;
		struct kvm_s2_mmu *mmu = vcpu->arch.hw_mmu;
		unsigned long vma_pagesize;
		enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R;
		struct kvm_pgtable *pgt;

		write_fault = kvm_is_write_fault(vcpu);
		exec_fault = kvm_vcpu_trap_is_iabt(vcpu);
		@@ -1543,22 +1544,24 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
		vma_pagesize = PAGE_SIZE;
		}

		/*
		* The stage2 has a minimum of 2 level table (For arm64 see
		* kvm_arm_setup_stage2()). Hence, we are guaranteed that we can
		* use PMD_SIZE huge mappings (even when the PMD is folded into PGD).
		* As for PUD huge maps, we must make sure that we have at least
		* 3 levels, i.e, PMD is not folded.
		*/
		if (vma_pagesize == PMD_SIZE \|\|
		(vma_pagesize == PUD_SIZE && kvm_stage2_has_pmd(kvm)))
		gfn = (fault_ipa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT;
		if (vma_pagesize == PMD_SIZE \|\| vma_pagesize == PUD_SIZE)
		fault_ipa &= huge_page_mask(hstate_vma(vma));

		gfn = fault_ipa >> PAGE_SHIFT;
		mmap_read_unlock(current->mm);

		/* We need minimum second+third level pages */
		ret = kvm_mmu_topup_memory_cache(memcache, kvm_mmu_cache_min_pages(kvm));
		/*
		* Permission faults just need to update the existing leaf entry,
		* and so normally don't require allocations from the memcache. The
		* only exception to this is when dirty logging is enabled at runtime
		* and a write fault needs to collapse a block entry into a table.
		*/
		if (fault_status != FSC_PERM \|\| (logging_active && write_fault)) {
		ret = kvm_mmu_topup_memory_cache(memcache,
		kvm_mmu_cache_min_pages(kvm));
		if (ret)
		return ret;
		}

		mmu_seq = vcpu->kvm->mmu_notifier_seq;
		/*
		@@ -1581,28 +1584,20 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
		return -EFAULT;

		if (kvm_is_device_pfn(pfn)) {
		mem_type = PAGE_S2_DEVICE;
		flags \|= KVM_S2PTE_FLAG_IS_IOMAP;
		} else if (logging_active) {
		/*
		* Faults on pages in a memslot with logging enabled
		* should not be mapped with huge pages (it introduces churn
		* and performance degradation), so force a pte mapping.
		*/
		flags \|= KVM_S2_FLAG_LOGGING_ACTIVE;

		device = true;
		} else if (logging_active && !write_fault) {
		/*
		* Only actually map the page as writable if this was a write
		* fault.
		*/
		if (!write_fault)
		writable = false;
		}

		if (exec_fault && is_iomap(flags))
		if (exec_fault && device)
		return -ENOEXEC;

		spin_lock(&kvm->mmu_lock);
		pgt = vcpu->arch.hw_mmu->pgt;
		if (mmu_notifier_retry(kvm, mmu_seq))
		goto out_unlock;

		@@ -1613,62 +1608,31 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
		if (vma_pagesize == PAGE_SIZE && !force_pte)
		vma_pagesize = transparent_hugepage_adjust(memslot, hva,
		&pfn, &fault_ipa);
		if (writable)
		if (writable) {
		prot \|= KVM_PGTABLE_PROT_W;
		kvm_set_pfn_dirty(pfn);
		mark_page_dirty(kvm, gfn);
		}

		if (fault_status != FSC_PERM && !is_iomap(flags))
		if (fault_status != FSC_PERM && !device)
		clean_dcache_guest_page(pfn, vma_pagesize);

		if (exec_fault)
		if (exec_fault) {
		prot \|= KVM_PGTABLE_PROT_X;
		invalidate_icache_guest_page(pfn, vma_pagesize);

		/*
		* If we took an execution fault we have made the
		* icache/dcache coherent above and should now let the s2
		* mapping be executable.
		*
		* Write faults (!exec_fault && FSC_PERM) are orthogonal to
		* execute permissions, and we preserve whatever we have.
		*/
		needs_exec = exec_fault \|\|
		(fault_status == FSC_PERM &&
		stage2_is_exec(mmu, fault_ipa, vma_pagesize));

		if (vma_pagesize == PUD_SIZE) {
		pud_t new_pud = kvm_pfn_pud(pfn, mem_type);

		new_pud = kvm_pud_mkhuge(new_pud);
		if (writable)
		new_pud = kvm_s2pud_mkwrite(new_pud);

		if (needs_exec)
		new_pud = kvm_s2pud_mkexec(new_pud);

		ret = stage2_set_pud_huge(mmu, memcache, fault_ipa, &new_pud);
		} else if (vma_pagesize == PMD_SIZE) {
		pmd_t new_pmd = kvm_pfn_pmd(pfn, mem_type);

		new_pmd = kvm_pmd_mkhuge(new_pmd);

		if (writable)
		new_pmd = kvm_s2pmd_mkwrite(new_pmd);

		if (needs_exec)
		new_pmd = kvm_s2pmd_mkexec(new_pmd);

		ret = stage2_set_pmd_huge(mmu, memcache, fault_ipa, &new_pmd);
		} else {
		pte_t new_pte = kvm_pfn_pte(pfn, mem_type);

		if (writable) {
		new_pte = kvm_s2pte_mkwrite(new_pte);
		mark_page_dirty(kvm, gfn);
		}

		if (needs_exec)
		new_pte = kvm_s2pte_mkexec(new_pte);
		if (device)
		prot \|= KVM_PGTABLE_PROT_DEVICE;
		else if (cpus_have_const_cap(ARM64_HAS_CACHE_DIC))
		prot \|= KVM_PGTABLE_PROT_X;

		ret = stage2_set_pte(mmu, memcache, fault_ipa, &new_pte, flags);
		if (fault_status == FSC_PERM && !(logging_active && writable)) {
		ret = kvm_pgtable_stage2_relax_perms(pgt, fault_ipa, prot);
		} else {
		ret = kvm_pgtable_stage2_map(pgt, fault_ipa, vma_pagesize,
		__pfn_to_phys(pfn), prot,
		memcache);
		}

		out_unlock:

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