diff options
Diffstat (limited to '')
-rw-r--r-- | arch/riscv/kvm/mmu.c | 802 |
1 files changed, 802 insertions, 0 deletions
diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c new file mode 100644 index 000000000..e47aeb6f0 --- /dev/null +++ b/arch/riscv/kvm/mmu.c @@ -0,0 +1,802 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2019 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <linux/bitops.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/hugetlb.h> +#include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/vmalloc.h> +#include <linux/kvm_host.h> +#include <linux/sched/signal.h> +#include <asm/csr.h> +#include <asm/page.h> +#include <asm/pgtable.h> + +#ifdef CONFIG_64BIT +static unsigned long gstage_mode = (HGATP_MODE_SV39X4 << HGATP_MODE_SHIFT); +static unsigned long gstage_pgd_levels = 3; +#define gstage_index_bits 9 +#else +static unsigned long gstage_mode = (HGATP_MODE_SV32X4 << HGATP_MODE_SHIFT); +static unsigned long gstage_pgd_levels = 2; +#define gstage_index_bits 10 +#endif + +#define gstage_pgd_xbits 2 +#define gstage_pgd_size (1UL << (HGATP_PAGE_SHIFT + gstage_pgd_xbits)) +#define gstage_gpa_bits (HGATP_PAGE_SHIFT + \ + (gstage_pgd_levels * gstage_index_bits) + \ + gstage_pgd_xbits) +#define gstage_gpa_size ((gpa_t)(1ULL << gstage_gpa_bits)) + +#define gstage_pte_leaf(__ptep) \ + (pte_val(*(__ptep)) & (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)) + +static inline unsigned long gstage_pte_index(gpa_t addr, u32 level) +{ + unsigned long mask; + unsigned long shift = HGATP_PAGE_SHIFT + (gstage_index_bits * level); + + if (level == (gstage_pgd_levels - 1)) + mask = (PTRS_PER_PTE * (1UL << gstage_pgd_xbits)) - 1; + else + mask = PTRS_PER_PTE - 1; + + return (addr >> shift) & mask; +} + +static inline unsigned long gstage_pte_page_vaddr(pte_t pte) +{ + return (unsigned long)pfn_to_virt(__page_val_to_pfn(pte_val(pte))); +} + +static int gstage_page_size_to_level(unsigned long page_size, u32 *out_level) +{ + u32 i; + unsigned long psz = 1UL << 12; + + for (i = 0; i < gstage_pgd_levels; i++) { + if (page_size == (psz << (i * gstage_index_bits))) { + *out_level = i; + return 0; + } + } + + return -EINVAL; +} + +static int gstage_level_to_page_order(u32 level, unsigned long *out_pgorder) +{ + if (gstage_pgd_levels < level) + return -EINVAL; + + *out_pgorder = 12 + (level * gstage_index_bits); + return 0; +} + +static int gstage_level_to_page_size(u32 level, unsigned long *out_pgsize) +{ + int rc; + unsigned long page_order = PAGE_SHIFT; + + rc = gstage_level_to_page_order(level, &page_order); + if (rc) + return rc; + + *out_pgsize = BIT(page_order); + return 0; +} + +static bool gstage_get_leaf_entry(struct kvm *kvm, gpa_t addr, + pte_t **ptepp, u32 *ptep_level) +{ + pte_t *ptep; + u32 current_level = gstage_pgd_levels - 1; + + *ptep_level = current_level; + ptep = (pte_t *)kvm->arch.pgd; + ptep = &ptep[gstage_pte_index(addr, current_level)]; + while (ptep && pte_val(*ptep)) { + if (gstage_pte_leaf(ptep)) { + *ptep_level = current_level; + *ptepp = ptep; + return true; + } + + if (current_level) { + current_level--; + *ptep_level = current_level; + ptep = (pte_t *)gstage_pte_page_vaddr(*ptep); + ptep = &ptep[gstage_pte_index(addr, current_level)]; + } else { + ptep = NULL; + } + } + + return false; +} + +static void gstage_remote_tlb_flush(struct kvm *kvm, u32 level, gpa_t addr) +{ + unsigned long order = PAGE_SHIFT; + + if (gstage_level_to_page_order(level, &order)) + return; + addr &= ~(BIT(order) - 1); + + kvm_riscv_hfence_gvma_vmid_gpa(kvm, -1UL, 0, addr, BIT(order), order); +} + +static int gstage_set_pte(struct kvm *kvm, u32 level, + struct kvm_mmu_memory_cache *pcache, + gpa_t addr, const pte_t *new_pte) +{ + u32 current_level = gstage_pgd_levels - 1; + pte_t *next_ptep = (pte_t *)kvm->arch.pgd; + pte_t *ptep = &next_ptep[gstage_pte_index(addr, current_level)]; + + if (current_level < level) + return -EINVAL; + + while (current_level != level) { + if (gstage_pte_leaf(ptep)) + return -EEXIST; + + if (!pte_val(*ptep)) { + if (!pcache) + return -ENOMEM; + next_ptep = kvm_mmu_memory_cache_alloc(pcache); + if (!next_ptep) + return -ENOMEM; + *ptep = pfn_pte(PFN_DOWN(__pa(next_ptep)), + __pgprot(_PAGE_TABLE)); + } else { + if (gstage_pte_leaf(ptep)) + return -EEXIST; + next_ptep = (pte_t *)gstage_pte_page_vaddr(*ptep); + } + + current_level--; + ptep = &next_ptep[gstage_pte_index(addr, current_level)]; + } + + *ptep = *new_pte; + if (gstage_pte_leaf(ptep)) + gstage_remote_tlb_flush(kvm, current_level, addr); + + return 0; +} + +static int gstage_map_page(struct kvm *kvm, + struct kvm_mmu_memory_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 = gstage_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 G-stage + * mapping. To support KVM dirty page logging with both options + * mentioned above, we will write-protect G-stage 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 gstage_set_pte(kvm, level, pcache, gpa, &new_pte); +} + +enum gstage_op { + GSTAGE_OP_NOP = 0, /* Nothing */ + GSTAGE_OP_CLEAR, /* Clear/Unmap */ + GSTAGE_OP_WP, /* Write-protect */ +}; + +static void gstage_op_pte(struct kvm *kvm, gpa_t addr, + pte_t *ptep, u32 ptep_level, enum gstage_op op) +{ + int i, ret; + pte_t *next_ptep; + u32 next_ptep_level; + unsigned long next_page_size, page_size; + + ret = gstage_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 && !gstage_pte_leaf(ptep)) { + next_ptep = (pte_t *)gstage_pte_page_vaddr(*ptep); + next_ptep_level = ptep_level - 1; + ret = gstage_level_to_page_size(next_ptep_level, + &next_page_size); + if (ret) + return; + + if (op == GSTAGE_OP_CLEAR) + set_pte(ptep, __pte(0)); + for (i = 0; i < PTRS_PER_PTE; i++) + gstage_op_pte(kvm, addr + i * next_page_size, + &next_ptep[i], next_ptep_level, op); + if (op == GSTAGE_OP_CLEAR) + put_page(virt_to_page(next_ptep)); + } else { + if (op == GSTAGE_OP_CLEAR) + set_pte(ptep, __pte(0)); + else if (op == GSTAGE_OP_WP) + set_pte(ptep, __pte(pte_val(*ptep) & ~_PAGE_WRITE)); + gstage_remote_tlb_flush(kvm, ptep_level, addr); + } +} + +static void gstage_unmap_range(struct kvm *kvm, gpa_t start, + gpa_t size, bool may_block) +{ + 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 = gstage_get_leaf_entry(kvm, addr, + &ptep, &ptep_level); + ret = gstage_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)) + gstage_op_pte(kvm, addr, ptep, + ptep_level, GSTAGE_OP_CLEAR); + +next: + addr += page_size; + + /* + * If the range is too large, release the kvm->mmu_lock + * to prevent starvation and lockup detector warnings. + */ + if (may_block && addr < end) + cond_resched_lock(&kvm->mmu_lock); + } +} + +static void gstage_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 = gstage_get_leaf_entry(kvm, addr, + &ptep, &ptep_level); + ret = gstage_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)) + gstage_op_pte(kvm, addr, ptep, + ptep_level, GSTAGE_OP_WP); + +next: + addr += page_size; + } +} + +static void gstage_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); + gstage_wp_range(kvm, start, end); + spin_unlock(&kvm->mmu_lock); + kvm_flush_remote_tlbs(kvm); +} + +int kvm_riscv_gstage_ioremap(struct kvm *kvm, gpa_t gpa, + phys_addr_t hpa, unsigned long size, + bool writable, bool in_atomic) +{ + pte_t pte; + int ret = 0; + unsigned long pfn; + phys_addr_t addr, end; + struct kvm_mmu_memory_cache pcache = { + .gfp_custom = (in_atomic) ? GFP_ATOMIC | __GFP_ACCOUNT : 0, + .gfp_zero = __GFP_ZERO, + }; + + 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_IO); + + if (!writable) + pte = pte_wrprotect(pte); + + ret = kvm_mmu_topup_memory_cache(&pcache, gstage_pgd_levels); + if (ret) + goto out; + + spin_lock(&kvm->mmu_lock); + ret = gstage_set_pte(kvm, 0, &pcache, addr, &pte); + spin_unlock(&kvm->mmu_lock); + if (ret) + goto out; + + pfn++; + } + +out: + kvm_mmu_free_memory_cache(&pcache); + return ret; +} + +void kvm_riscv_gstage_iounmap(struct kvm *kvm, gpa_t gpa, unsigned long size) +{ + spin_lock(&kvm->mmu_lock); + gstage_unmap_range(kvm, gpa, size, false); + spin_unlock(&kvm->mmu_lock); +} + +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; + + gstage_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) +{ +} + +void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) +{ +} + +void kvm_arch_flush_shadow_all(struct kvm *kvm) +{ + kvm_riscv_gstage_free_pgd(kvm); +} + +void kvm_arch_flush_shadow_memslot(struct kvm *kvm, + struct kvm_memory_slot *slot) +{ + gpa_t gpa = slot->base_gfn << PAGE_SHIFT; + phys_addr_t size = slot->npages << PAGE_SHIFT; + + spin_lock(&kvm->mmu_lock); + gstage_unmap_range(kvm, gpa, size, false); + spin_unlock(&kvm->mmu_lock); +} + +void kvm_arch_commit_memory_region(struct kvm *kvm, + struct kvm_memory_slot *old, + const struct kvm_memory_slot *new, + enum kvm_mr_change change) +{ + /* + * 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 && new->flags & KVM_MEM_LOG_DIRTY_PAGES) + gstage_wp_memory_region(kvm, new->id); +} + +int kvm_arch_prepare_memory_region(struct kvm *kvm, + const struct kvm_memory_slot *old, + struct kvm_memory_slot *new, + enum kvm_mr_change change) +{ + hva_t hva, reg_end, size; + gpa_t base_gpa; + bool writable; + 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 ((new->base_gfn + new->npages) >= + (gstage_gpa_size >> PAGE_SHIFT)) + return -EFAULT; + + hva = new->userspace_addr; + size = new->npages << PAGE_SHIFT; + reg_end = hva + size; + base_gpa = new->base_gfn << PAGE_SHIFT; + writable = !(new->flags & KVM_MEM_READONLY); + + 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 = base_gpa + (vm_start - hva); + 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 (new->flags & KVM_MEM_LOG_DIRTY_PAGES) { + ret = -EINVAL; + goto out; + } + + ret = kvm_riscv_gstage_ioremap(kvm, gpa, pa, + vm_end - vm_start, + writable, false); + 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) + gstage_unmap_range(kvm, base_gpa, size, false); + spin_unlock(&kvm->mmu_lock); + +out: + mmap_read_unlock(current->mm); + return ret; +} + +bool kvm_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range) +{ + if (!kvm->arch.pgd) + return false; + + gstage_unmap_range(kvm, range->start << PAGE_SHIFT, + (range->end - range->start) << PAGE_SHIFT, + range->may_block); + return false; +} + +bool kvm_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range) +{ + int ret; + kvm_pfn_t pfn = pte_pfn(range->pte); + + if (!kvm->arch.pgd) + return false; + + WARN_ON(range->end - range->start != 1); + + ret = gstage_map_page(kvm, NULL, range->start << PAGE_SHIFT, + __pfn_to_phys(pfn), PAGE_SIZE, true, true); + if (ret) { + kvm_debug("Failed to map G-stage page (error %d)\n", ret); + return true; + } + + return false; +} + +bool kvm_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) +{ + pte_t *ptep; + u32 ptep_level = 0; + u64 size = (range->end - range->start) << PAGE_SHIFT; + + if (!kvm->arch.pgd) + return false; + + WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PGDIR_SIZE); + + if (!gstage_get_leaf_entry(kvm, range->start << PAGE_SHIFT, + &ptep, &ptep_level)) + return false; + + return ptep_test_and_clear_young(NULL, 0, ptep); +} + +bool kvm_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range) +{ + pte_t *ptep; + u32 ptep_level = 0; + u64 size = (range->end - range->start) << PAGE_SHIFT; + + if (!kvm->arch.pgd) + return false; + + WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PGDIR_SIZE); + + if (!gstage_get_leaf_entry(kvm, range->start << PAGE_SHIFT, + &ptep, &ptep_level)) + return false; + + return pte_young(*ptep); +} + +int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu, + struct kvm_memory_slot *memslot, + gpa_t gpa, unsigned long hva, bool is_write) +{ + int ret; + kvm_pfn_t hfn; + bool writable; + short vma_pageshift; + gfn_t gfn = gpa >> PAGE_SHIFT; + struct vm_area_struct *vma; + struct kvm *kvm = vcpu->kvm; + struct kvm_mmu_memory_cache *pcache = &vcpu->arch.mmu_page_cache; + bool logging = (memslot->dirty_bitmap && + !(memslot->flags & KVM_MEM_READONLY)) ? true : false; + unsigned long vma_pagesize, mmu_seq; + + /* We need minimum second+third level pages */ + ret = kvm_mmu_topup_memory_cache(pcache, gstage_pgd_levels); + if (ret) { + kvm_err("Failed to topup G-stage cache\n"); + return ret; + } + + 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; + + /* + * Read mmu_invalidate_seq so that KVM can detect if the results of + * vma_lookup() or gfn_to_pfn_prot() become stale priort to acquiring + * kvm->mmu_lock. + * + * Rely on mmap_read_unlock() for an implicit smp_rmb(), which pairs + * with the smp_wmb() in kvm_mmu_invalidate_end(). + */ + mmu_seq = kvm->mmu_invalidate_seq; + 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; + } + + hfn = gfn_to_pfn_prot(kvm, gfn, is_write, &writable); + 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) + writable = false; + + spin_lock(&kvm->mmu_lock); + + if (mmu_invalidate_retry(kvm, mmu_seq)) + goto out_unlock; + + if (writable) { + kvm_set_pfn_dirty(hfn); + mark_page_dirty(kvm, gfn); + ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT, + vma_pagesize, false, true); + } else { + ret = gstage_map_page(kvm, pcache, gpa, hfn << PAGE_SHIFT, + vma_pagesize, true, true); + } + + if (ret) + kvm_err("Failed to map in G-stage\n"); + +out_unlock: + spin_unlock(&kvm->mmu_lock); + kvm_set_pfn_accessed(hfn); + kvm_release_pfn_clean(hfn); + return ret; +} + +int kvm_riscv_gstage_alloc_pgd(struct kvm *kvm) +{ + 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(gstage_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_gstage_free_pgd(struct kvm *kvm) +{ + void *pgd = NULL; + + spin_lock(&kvm->mmu_lock); + if (kvm->arch.pgd) { + gstage_unmap_range(kvm, 0UL, gstage_gpa_size, false); + 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(gstage_pgd_size)); +} + +void kvm_riscv_gstage_update_hgatp(struct kvm_vcpu *vcpu) +{ + unsigned long hgatp = gstage_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_gstage_vmid_bits()) + kvm_riscv_local_hfence_gvma_all(); +} + +void kvm_riscv_gstage_mode_detect(void) +{ +#ifdef CONFIG_64BIT + /* Try Sv57x4 G-stage mode */ + csr_write(CSR_HGATP, HGATP_MODE_SV57X4 << HGATP_MODE_SHIFT); + if ((csr_read(CSR_HGATP) >> HGATP_MODE_SHIFT) == HGATP_MODE_SV57X4) { + gstage_mode = (HGATP_MODE_SV57X4 << HGATP_MODE_SHIFT); + gstage_pgd_levels = 5; + goto skip_sv48x4_test; + } + + /* Try Sv48x4 G-stage mode */ + csr_write(CSR_HGATP, HGATP_MODE_SV48X4 << HGATP_MODE_SHIFT); + if ((csr_read(CSR_HGATP) >> HGATP_MODE_SHIFT) == HGATP_MODE_SV48X4) { + gstage_mode = (HGATP_MODE_SV48X4 << HGATP_MODE_SHIFT); + gstage_pgd_levels = 4; + } +skip_sv48x4_test: + + csr_write(CSR_HGATP, 0); + kvm_riscv_local_hfence_gvma_all(); +#endif +} + +unsigned long kvm_riscv_gstage_mode(void) +{ + return gstage_mode >> HGATP_MODE_SHIFT; +} + +int kvm_riscv_gstage_gpa_bits(void) +{ + return gstage_gpa_bits; +} |