From 9d05c1fee837572d91f2b5463d67d4e098987e95 Mon Sep 17 00:00:00 2001 From: Anup Patel Date: Mon, 27 Sep 2021 17:10:09 +0530 Subject: [PATCH] RISC-V: KVM: Implement stage2 page table programming This patch implements all required functions for programming the stage2 page table for each Guest/VM. At high-level, the flow of stage2 related functions is similar from KVM ARM/ARM64 implementation but the stage2 page table format is quite different for KVM RISC-V. [jiangyifei: stage2 dirty log support] Signed-off-by: Yifei Jiang Signed-off-by: Anup Patel Acked-by: Paolo Bonzini Reviewed-by: Paolo Bonzini Acked-by: Palmer Dabbelt --- arch/riscv/include/asm/kvm_host.h | 12 + arch/riscv/kvm/Kconfig | 1 + arch/riscv/kvm/main.c | 19 + arch/riscv/kvm/mmu.c | 654 +++++++++++++++++++++++++++++- arch/riscv/kvm/vm.c | 6 - 5 files changed, 676 insertions(+), 16 deletions(-) diff --git a/arch/riscv/include/asm/kvm_host.h b/arch/riscv/include/asm/kvm_host.h index 69c342430242..2e71a353395e 100644 --- a/arch/riscv/include/asm/kvm_host.h +++ b/arch/riscv/include/asm/kvm_host.h @@ -70,6 +70,13 @@ struct kvm_mmio_decode { int return_handled; }; +#define KVM_MMU_PAGE_CACHE_NR_OBJS 32 + +struct kvm_mmu_page_cache { + int nobjs; + void *objects[KVM_MMU_PAGE_CACHE_NR_OBJS]; +}; + struct kvm_cpu_trap { unsigned long sepc; unsigned long scause; @@ -171,6 +178,9 @@ struct kvm_vcpu_arch { /* MMIO instruction details */ struct kvm_mmio_decode mmio_decode; + /* Cache pages needed to program page tables with spinlock held */ + struct kvm_mmu_page_cache mmu_page_cache; + /* VCPU power-off state */ bool power_off; @@ -198,6 +208,8 @@ void kvm_riscv_stage2_flush_cache(struct kvm_vcpu *vcpu); int kvm_riscv_stage2_alloc_pgd(struct kvm *kvm); void kvm_riscv_stage2_free_pgd(struct kvm *kvm); void kvm_riscv_stage2_update_hgatp(struct kvm_vcpu *vcpu); +void kvm_riscv_stage2_mode_detect(void); +unsigned long kvm_riscv_stage2_mode(void); void kvm_riscv_stage2_vmid_detect(void); unsigned long kvm_riscv_stage2_vmid_bits(void); diff --git a/arch/riscv/kvm/Kconfig b/arch/riscv/kvm/Kconfig index b42979f84042..633063edaee8 100644 --- a/arch/riscv/kvm/Kconfig +++ b/arch/riscv/kvm/Kconfig @@ -23,6 +23,7 @@ config KVM select PREEMPT_NOTIFIERS select ANON_INODES select KVM_MMIO + select KVM_GENERIC_DIRTYLOG_READ_PROTECT select HAVE_KVM_VCPU_ASYNC_IOCTL select HAVE_KVM_EVENTFD select SRCU diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c index 49a4941e3838..421ecf4e6360 100644 --- a/arch/riscv/kvm/main.c +++ b/arch/riscv/kvm/main.c @@ -64,6 +64,8 @@ void kvm_arch_hardware_disable(void) int kvm_arch_init(void *opaque) { + const char *str; + if (!riscv_isa_extension_available(NULL, h)) { kvm_info("hypervisor extension not available\n"); return -ENODEV; @@ -79,10 +81,27 @@ int kvm_arch_init(void *opaque) return -ENODEV; } + kvm_riscv_stage2_mode_detect(); + kvm_riscv_stage2_vmid_detect(); kvm_info("hypervisor extension available\n"); + switch (kvm_riscv_stage2_mode()) { + case HGATP_MODE_SV32X4: + str = "Sv32x4"; + break; + case HGATP_MODE_SV39X4: + str = "Sv39x4"; + break; + case HGATP_MODE_SV48X4: + str = "Sv48x4"; + break; + default: + return -ENODEV; + } + kvm_info("using %s G-stage page table format\n", str); + kvm_info("VMID %ld bits available\n", kvm_riscv_stage2_vmid_bits()); return 0; diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c index 8ec10ef861e7..fa9a4f9b9542 100644 --- a/arch/riscv/kvm/mmu.c +++ b/arch/riscv/kvm/mmu.c @@ -15,13 +15,421 @@ #include #include #include +#include #include #include +#include + +#ifdef CONFIG_64BIT +static unsigned long stage2_mode = (HGATP_MODE_SV39X4 << HGATP_MODE_SHIFT); +static unsigned long stage2_pgd_levels = 3; +#define stage2_index_bits 9 +#else +static unsigned long stage2_mode = (HGATP_MODE_SV32X4 << HGATP_MODE_SHIFT); +static unsigned long stage2_pgd_levels = 2; +#define stage2_index_bits 10 +#endif + +#define stage2_pgd_xbits 2 +#define stage2_pgd_size (1UL << (HGATP_PAGE_SHIFT + stage2_pgd_xbits)) +#define stage2_gpa_bits (HGATP_PAGE_SHIFT + \ + (stage2_pgd_levels * stage2_index_bits) + \ + stage2_pgd_xbits) +#define stage2_gpa_size ((gpa_t)(1ULL << stage2_gpa_bits)) + +#define stage2_pte_leaf(__ptep) \ + (pte_val(*(__ptep)) & (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)) + +static inline unsigned long stage2_pte_index(gpa_t addr, u32 level) +{ + unsigned long mask; + unsigned long shift = HGATP_PAGE_SHIFT + (stage2_index_bits * level); + + if (level == (stage2_pgd_levels - 1)) + mask = (PTRS_PER_PTE * (1UL << stage2_pgd_xbits)) - 1; + else + mask = PTRS_PER_PTE - 1; + + return (addr >> shift) & mask; +} + +static inline unsigned long stage2_pte_page_vaddr(pte_t pte) +{ + return (unsigned long)pfn_to_virt(pte_val(pte) >> _PAGE_PFN_SHIFT); +} + +static int stage2_page_size_to_level(unsigned long page_size, u32 *out_level) +{ + u32 i; + unsigned long psz = 1UL << 12; + + for (i = 0; i < stage2_pgd_levels; i++) { + if (page_size == (psz << (i * stage2_index_bits))) { + *out_level = i; + return 0; + } + } + + return -EINVAL; +} + +static int stage2_level_to_page_size(u32 level, unsigned long *out_pgsize) +{ + if (stage2_pgd_levels < level) + return -EINVAL; + + *out_pgsize = 1UL << (12 + (level * stage2_index_bits)); + + return 0; +} + +static int stage2_cache_topup(struct kvm_mmu_page_cache *pcache, + int min, int max) +{ + void *page; + + BUG_ON(max > KVM_MMU_PAGE_CACHE_NR_OBJS); + if (pcache->nobjs >= min) + return 0; + while (pcache->nobjs < max) { + page = (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO); + if (!page) + return -ENOMEM; + pcache->objects[pcache->nobjs++] = page; + } + + return 0; +} + +static void stage2_cache_flush(struct kvm_mmu_page_cache *pcache) +{ + while (pcache && pcache->nobjs) + free_page((unsigned long)pcache->objects[--pcache->nobjs]); +} + +static void *stage2_cache_alloc(struct kvm_mmu_page_cache *pcache) +{ + void *p; + + if (!pcache) + return NULL; + + BUG_ON(!pcache->nobjs); + p = pcache->objects[--pcache->nobjs]; + + return p; +} + +static bool stage2_get_leaf_entry(struct kvm *kvm, gpa_t addr, + pte_t **ptepp, u32 *ptep_level) +{ + pte_t *ptep; + u32 current_level = stage2_pgd_levels - 1; + + *ptep_level = current_level; + ptep = (pte_t *)kvm->arch.pgd; + ptep = &ptep[stage2_pte_index(addr, current_level)]; + while (ptep && pte_val(*ptep)) { + if (stage2_pte_leaf(ptep)) { + *ptep_level = current_level; + *ptepp = ptep; + return true; + } + + if (current_level) { + current_level--; + *ptep_level = current_level; + ptep = (pte_t *)stage2_pte_page_vaddr(*ptep); + ptep = &ptep[stage2_pte_index(addr, current_level)]; + } else { + ptep = NULL; + } + } + + return false; +} + +static void stage2_remote_tlb_flush(struct kvm *kvm, u32 level, gpa_t addr) +{ + struct cpumask hmask; + unsigned long size = PAGE_SIZE; + struct kvm_vmid *vmid = &kvm->arch.vmid; + + if (stage2_level_to_page_size(level, &size)) + return; + addr &= ~(size - 1); + + /* + * TODO: Instead of cpu_online_mask, we should only target CPUs + * where the Guest/VM is running. + */ + preempt_disable(); + riscv_cpuid_to_hartid_mask(cpu_online_mask, &hmask); + sbi_remote_hfence_gvma_vmid(cpumask_bits(&hmask), addr, size, + READ_ONCE(vmid->vmid)); + preempt_enable(); +} + +static int stage2_set_pte(struct kvm *kvm, u32 level, + struct kvm_mmu_page_cache *pcache, + gpa_t addr, const pte_t *new_pte) +{ + u32 current_level = stage2_pgd_levels - 1; + pte_t *next_ptep = (pte_t *)kvm->arch.pgd; + pte_t *ptep = &next_ptep[stage2_pte_index(addr, current_level)]; + + if (current_level < level) + return -EINVAL; + + while (current_level != level) { + if (stage2_pte_leaf(ptep)) + return -EEXIST; + + if (!pte_val(*ptep)) { + next_ptep = stage2_cache_alloc(pcache); + if (!next_ptep) + return -ENOMEM; + *ptep = pfn_pte(PFN_DOWN(__pa(next_ptep)), + __pgprot(_PAGE_TABLE)); + } else { + if (stage2_pte_leaf(ptep)) + return -EEXIST; + next_ptep = (pte_t *)stage2_pte_page_vaddr(*ptep); + } + + current_level--; + ptep = &next_ptep[stage2_pte_index(addr, current_level)]; + } + + *ptep = *new_pte; + if (stage2_pte_leaf(ptep)) + stage2_remote_tlb_flush(kvm, current_level, addr); + + return 0; +} + +static int stage2_map_page(struct kvm *kvm, + struct kvm_mmu_page_cache *pcache, + gpa_t gpa, phys_addr_t hpa, + unsigned long page_size, + bool page_rdonly, bool page_exec) +{ + int ret; + u32 level = 0; + pte_t new_pte; + pgprot_t prot; + + ret = stage2_page_size_to_level(page_size, &level); + if (ret) + return ret; + + /* + * A RISC-V implementation can choose to either: + * 1) Update 'A' and 'D' PTE bits in hardware + * 2) Generate page fault when 'A' and/or 'D' bits are not set + * PTE so that software can update these bits. + * + * We support both options mentioned above. To achieve this, we + * always set 'A' and 'D' PTE bits at time of creating stage2 + * mapping. To support KVM dirty page logging with both options + * mentioned above, we will write-protect stage2 PTEs to track + * dirty pages. + */ + + if (page_exec) { + if (page_rdonly) + prot = PAGE_READ_EXEC; + else + prot = PAGE_WRITE_EXEC; + } else { + if (page_rdonly) + prot = PAGE_READ; + else + prot = PAGE_WRITE; + } + new_pte = pfn_pte(PFN_DOWN(hpa), prot); + new_pte = pte_mkdirty(new_pte); + + return stage2_set_pte(kvm, level, pcache, gpa, &new_pte); +} + +enum stage2_op { + STAGE2_OP_NOP = 0, /* Nothing */ + STAGE2_OP_CLEAR, /* Clear/Unmap */ + STAGE2_OP_WP, /* Write-protect */ +}; + +static void stage2_op_pte(struct kvm *kvm, gpa_t addr, + pte_t *ptep, u32 ptep_level, enum stage2_op op) +{ + int i, ret; + pte_t *next_ptep; + u32 next_ptep_level; + unsigned long next_page_size, page_size; + + ret = stage2_level_to_page_size(ptep_level, &page_size); + if (ret) + return; + + BUG_ON(addr & (page_size - 1)); + + if (!pte_val(*ptep)) + return; + + if (ptep_level && !stage2_pte_leaf(ptep)) { + next_ptep = (pte_t *)stage2_pte_page_vaddr(*ptep); + next_ptep_level = ptep_level - 1; + ret = stage2_level_to_page_size(next_ptep_level, + &next_page_size); + if (ret) + return; + + if (op == STAGE2_OP_CLEAR) + set_pte(ptep, __pte(0)); + for (i = 0; i < PTRS_PER_PTE; i++) + stage2_op_pte(kvm, addr + i * next_page_size, + &next_ptep[i], next_ptep_level, op); + if (op == STAGE2_OP_CLEAR) + put_page(virt_to_page(next_ptep)); + } else { + if (op == STAGE2_OP_CLEAR) + set_pte(ptep, __pte(0)); + else if (op == STAGE2_OP_WP) + set_pte(ptep, __pte(pte_val(*ptep) & ~_PAGE_WRITE)); + stage2_remote_tlb_flush(kvm, ptep_level, addr); + } +} + +static void stage2_unmap_range(struct kvm *kvm, gpa_t start, gpa_t size) +{ + int ret; + pte_t *ptep; + u32 ptep_level; + bool found_leaf; + unsigned long page_size; + gpa_t addr = start, end = start + size; + + while (addr < end) { + found_leaf = stage2_get_leaf_entry(kvm, addr, + &ptep, &ptep_level); + ret = stage2_level_to_page_size(ptep_level, &page_size); + if (ret) + break; + + if (!found_leaf) + goto next; + + if (!(addr & (page_size - 1)) && ((end - addr) >= page_size)) + stage2_op_pte(kvm, addr, ptep, + ptep_level, STAGE2_OP_CLEAR); + +next: + addr += page_size; + } +} + +static void stage2_wp_range(struct kvm *kvm, gpa_t start, gpa_t end) +{ + int ret; + pte_t *ptep; + u32 ptep_level; + bool found_leaf; + gpa_t addr = start; + unsigned long page_size; + + while (addr < end) { + found_leaf = stage2_get_leaf_entry(kvm, addr, + &ptep, &ptep_level); + ret = stage2_level_to_page_size(ptep_level, &page_size); + if (ret) + break; + + if (!found_leaf) + goto next; + + if (!(addr & (page_size - 1)) && ((end - addr) >= page_size)) + stage2_op_pte(kvm, addr, ptep, + ptep_level, STAGE2_OP_WP); + +next: + addr += page_size; + } +} + +static void stage2_wp_memory_region(struct kvm *kvm, int slot) +{ + struct kvm_memslots *slots = kvm_memslots(kvm); + struct kvm_memory_slot *memslot = id_to_memslot(slots, slot); + phys_addr_t start = memslot->base_gfn << PAGE_SHIFT; + phys_addr_t end = (memslot->base_gfn + memslot->npages) << PAGE_SHIFT; + + spin_lock(&kvm->mmu_lock); + stage2_wp_range(kvm, start, end); + spin_unlock(&kvm->mmu_lock); + kvm_flush_remote_tlbs(kvm); +} + +static int stage2_ioremap(struct kvm *kvm, gpa_t gpa, phys_addr_t hpa, + unsigned long size, bool writable) +{ + pte_t pte; + int ret = 0; + unsigned long pfn; + phys_addr_t addr, end; + struct kvm_mmu_page_cache pcache = { 0, }; + + end = (gpa + size + PAGE_SIZE - 1) & PAGE_MASK; + pfn = __phys_to_pfn(hpa); + + for (addr = gpa; addr < end; addr += PAGE_SIZE) { + pte = pfn_pte(pfn, PAGE_KERNEL); + + if (!writable) + pte = pte_wrprotect(pte); + + ret = stage2_cache_topup(&pcache, + stage2_pgd_levels, + KVM_MMU_PAGE_CACHE_NR_OBJS); + if (ret) + goto out; + + spin_lock(&kvm->mmu_lock); + ret = stage2_set_pte(kvm, 0, &pcache, addr, &pte); + spin_unlock(&kvm->mmu_lock); + if (ret) + goto out; + + pfn++; + } + +out: + stage2_cache_flush(&pcache); + return ret; + +} + +void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm, + struct kvm_memory_slot *slot, + gfn_t gfn_offset, + unsigned long mask) +{ + phys_addr_t base_gfn = slot->base_gfn + gfn_offset; + phys_addr_t start = (base_gfn + __ffs(mask)) << PAGE_SHIFT; + phys_addr_t end = (base_gfn + __fls(mask) + 1) << PAGE_SHIFT; + + stage2_wp_range(kvm, start, end); +} void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot) { } +void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm, + const struct kvm_memory_slot *memslot) +{ + kvm_flush_remote_tlbs(kvm); +} + void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free) { } @@ -32,7 +440,7 @@ void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) void kvm_arch_flush_shadow_all(struct kvm *kvm) { - /* TODO: */ + kvm_riscv_stage2_free_pgd(kvm); } void kvm_arch_flush_shadow_memslot(struct kvm *kvm, @@ -46,7 +454,13 @@ void kvm_arch_commit_memory_region(struct kvm *kvm, const struct kvm_memory_slot *new, enum kvm_mr_change change) { - /* TODO: */ + /* + * At this point memslot has been committed and there is an + * allocated dirty_bitmap[], dirty pages will be tracked while + * the memory slot is write protected. + */ + if (change != KVM_MR_DELETE && mem->flags & KVM_MEM_LOG_DIRTY_PAGES) + stage2_wp_memory_region(kvm, mem->slot); } int kvm_arch_prepare_memory_region(struct kvm *kvm, @@ -54,35 +468,255 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm, const struct kvm_userspace_memory_region *mem, enum kvm_mr_change change) { - /* TODO: */ - return 0; + hva_t hva = mem->userspace_addr; + hva_t reg_end = hva + mem->memory_size; + bool writable = !(mem->flags & KVM_MEM_READONLY); + int ret = 0; + + if (change != KVM_MR_CREATE && change != KVM_MR_MOVE && + change != KVM_MR_FLAGS_ONLY) + return 0; + + /* + * Prevent userspace from creating a memory region outside of the GPA + * space addressable by the KVM guest GPA space. + */ + if ((memslot->base_gfn + memslot->npages) >= + (stage2_gpa_size >> PAGE_SHIFT)) + return -EFAULT; + + mmap_read_lock(current->mm); + + /* + * A memory region could potentially cover multiple VMAs, and + * any holes between them, so iterate over all of them to find + * out if we can map any of them right now. + * + * +--------------------------------------------+ + * +---------------+----------------+ +----------------+ + * | : VMA 1 | VMA 2 | | VMA 3 : | + * +---------------+----------------+ +----------------+ + * | memory region | + * +--------------------------------------------+ + */ + do { + struct vm_area_struct *vma = find_vma(current->mm, hva); + hva_t vm_start, vm_end; + + if (!vma || vma->vm_start >= reg_end) + break; + + /* + * Mapping a read-only VMA is only allowed if the + * memory region is configured as read-only. + */ + if (writable && !(vma->vm_flags & VM_WRITE)) { + ret = -EPERM; + break; + } + + /* Take the intersection of this VMA with the memory region */ + vm_start = max(hva, vma->vm_start); + vm_end = min(reg_end, vma->vm_end); + + if (vma->vm_flags & VM_PFNMAP) { + gpa_t gpa = mem->guest_phys_addr + + (vm_start - mem->userspace_addr); + phys_addr_t pa; + + pa = (phys_addr_t)vma->vm_pgoff << PAGE_SHIFT; + pa += vm_start - vma->vm_start; + + /* IO region dirty page logging not allowed */ + if (memslot->flags & KVM_MEM_LOG_DIRTY_PAGES) { + ret = -EINVAL; + goto out; + } + + ret = stage2_ioremap(kvm, gpa, pa, + vm_end - vm_start, writable); + if (ret) + break; + } + hva = vm_end; + } while (hva < reg_end); + + if (change == KVM_MR_FLAGS_ONLY) + goto out; + + spin_lock(&kvm->mmu_lock); + if (ret) + stage2_unmap_range(kvm, mem->guest_phys_addr, + mem->memory_size); + spin_unlock(&kvm->mmu_lock); + +out: + mmap_read_unlock(current->mm); + return ret; } int kvm_riscv_stage2_map(struct kvm_vcpu *vcpu, struct kvm_memory_slot *memslot, gpa_t gpa, unsigned long hva, bool is_write) { - /* TODO: */ - return 0; + int ret; + kvm_pfn_t hfn; + bool writeable; + short vma_pageshift; + gfn_t gfn = gpa >> PAGE_SHIFT; + struct vm_area_struct *vma; + struct kvm *kvm = vcpu->kvm; + struct kvm_mmu_page_cache *pcache = &vcpu->arch.mmu_page_cache; + bool logging = (memslot->dirty_bitmap && + !(memslot->flags & KVM_MEM_READONLY)) ? true : false; + unsigned long vma_pagesize; + + mmap_read_lock(current->mm); + + vma = find_vma_intersection(current->mm, hva, hva + 1); + if (unlikely(!vma)) { + kvm_err("Failed to find VMA for hva 0x%lx\n", hva); + mmap_read_unlock(current->mm); + return -EFAULT; + } + + if (is_vm_hugetlb_page(vma)) + vma_pageshift = huge_page_shift(hstate_vma(vma)); + else + vma_pageshift = PAGE_SHIFT; + vma_pagesize = 1ULL << vma_pageshift; + if (logging || (vma->vm_flags & VM_PFNMAP)) + vma_pagesize = PAGE_SIZE; + + if (vma_pagesize == PMD_SIZE || vma_pagesize == PGDIR_SIZE) + gfn = (gpa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT; + + mmap_read_unlock(current->mm); + + if (vma_pagesize != PGDIR_SIZE && + vma_pagesize != PMD_SIZE && + vma_pagesize != PAGE_SIZE) { + kvm_err("Invalid VMA page size 0x%lx\n", vma_pagesize); + return -EFAULT; + } + + /* We need minimum second+third level pages */ + ret = stage2_cache_topup(pcache, stage2_pgd_levels, + KVM_MMU_PAGE_CACHE_NR_OBJS); + if (ret) { + kvm_err("Failed to topup stage2 cache\n"); + return ret; + } + + hfn = gfn_to_pfn_prot(kvm, gfn, is_write, &writeable); + if (hfn == KVM_PFN_ERR_HWPOISON) { + send_sig_mceerr(BUS_MCEERR_AR, (void __user *)hva, + vma_pageshift, current); + return 0; + } + if (is_error_noslot_pfn(hfn)) + return -EFAULT; + + /* + * If logging is active then we allow writable pages only + * for write faults. + */ + if (logging && !is_write) + writeable = false; + + spin_lock(&kvm->mmu_lock); + + if (writeable) { + kvm_set_pfn_dirty(hfn); + mark_page_dirty(kvm, gfn); + ret = stage2_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT, + vma_pagesize, false, true); + } else { + ret = stage2_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT, + vma_pagesize, true, true); + } + + if (ret) + kvm_err("Failed to map in stage2\n"); + + spin_unlock(&kvm->mmu_lock); + kvm_set_pfn_accessed(hfn); + kvm_release_pfn_clean(hfn); + return ret; } void kvm_riscv_stage2_flush_cache(struct kvm_vcpu *vcpu) { - /* TODO: */ + stage2_cache_flush(&vcpu->arch.mmu_page_cache); } int kvm_riscv_stage2_alloc_pgd(struct kvm *kvm) { - /* TODO: */ + struct page *pgd_page; + + if (kvm->arch.pgd != NULL) { + kvm_err("kvm_arch already initialized?\n"); + return -EINVAL; + } + + pgd_page = alloc_pages(GFP_KERNEL | __GFP_ZERO, + get_order(stage2_pgd_size)); + if (!pgd_page) + return -ENOMEM; + kvm->arch.pgd = page_to_virt(pgd_page); + kvm->arch.pgd_phys = page_to_phys(pgd_page); + return 0; } void kvm_riscv_stage2_free_pgd(struct kvm *kvm) { - /* TODO: */ + void *pgd = NULL; + + spin_lock(&kvm->mmu_lock); + if (kvm->arch.pgd) { + stage2_unmap_range(kvm, 0UL, stage2_gpa_size); + pgd = READ_ONCE(kvm->arch.pgd); + kvm->arch.pgd = NULL; + kvm->arch.pgd_phys = 0; + } + spin_unlock(&kvm->mmu_lock); + + if (pgd) + free_pages((unsigned long)pgd, get_order(stage2_pgd_size)); } void kvm_riscv_stage2_update_hgatp(struct kvm_vcpu *vcpu) { - /* TODO: */ + unsigned long hgatp = stage2_mode; + struct kvm_arch *k = &vcpu->kvm->arch; + + hgatp |= (READ_ONCE(k->vmid.vmid) << HGATP_VMID_SHIFT) & + HGATP_VMID_MASK; + hgatp |= (k->pgd_phys >> PAGE_SHIFT) & HGATP_PPN; + + csr_write(CSR_HGATP, hgatp); + + if (!kvm_riscv_stage2_vmid_bits()) + __kvm_riscv_hfence_gvma_all(); +} + +void kvm_riscv_stage2_mode_detect(void) +{ +#ifdef CONFIG_64BIT + /* Try Sv48x4 stage2 mode */ + csr_write(CSR_HGATP, HGATP_MODE_SV48X4 << HGATP_MODE_SHIFT); + if ((csr_read(CSR_HGATP) >> HGATP_MODE_SHIFT) == HGATP_MODE_SV48X4) { + stage2_mode = (HGATP_MODE_SV48X4 << HGATP_MODE_SHIFT); + stage2_pgd_levels = 4; + } + csr_write(CSR_HGATP, 0); + + __kvm_riscv_hfence_gvma_all(); +#endif +} + +unsigned long kvm_riscv_stage2_mode(void) +{ + return stage2_mode >> HGATP_MODE_SHIFT; } diff --git a/arch/riscv/kvm/vm.c b/arch/riscv/kvm/vm.c index 42e75dc8ab06..e2834ab9044c 100644 --- a/arch/riscv/kvm/vm.c +++ b/arch/riscv/kvm/vm.c @@ -27,12 +27,6 @@ const struct kvm_stats_header kvm_vm_stats_header = { sizeof(kvm_vm_stats_desc), }; -int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) -{ - /* TODO: To be added later. */ - return -EOPNOTSUPP; -} - int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) { int r;