diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_64_mmu_radix.c')
-rw-r--r-- | arch/powerpc/kvm/book3s_64_mmu_radix.c | 348 |
1 files changed, 221 insertions, 127 deletions
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c index 481da8f93fa4..176f911ee983 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c @@ -139,44 +139,24 @@ int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, return 0; } -#ifdef CONFIG_PPC_64K_PAGES -#define MMU_BASE_PSIZE MMU_PAGE_64K -#else -#define MMU_BASE_PSIZE MMU_PAGE_4K -#endif - static void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr, unsigned int pshift) { - int psize = MMU_BASE_PSIZE; - - if (pshift >= PUD_SHIFT) - psize = MMU_PAGE_1G; - else if (pshift >= PMD_SHIFT) - psize = MMU_PAGE_2M; - addr &= ~0xfffUL; - addr |= mmu_psize_defs[psize].ap << 5; - asm volatile("ptesync": : :"memory"); - asm volatile(PPC_TLBIE_5(%0, %1, 0, 0, 1) - : : "r" (addr), "r" (kvm->arch.lpid) : "memory"); - if (cpu_has_feature(CPU_FTR_P9_TLBIE_BUG)) - asm volatile(PPC_TLBIE_5(%0, %1, 0, 0, 1) - : : "r" (addr), "r" (kvm->arch.lpid) : "memory"); - asm volatile("eieio ; tlbsync ; ptesync": : :"memory"); + unsigned long psize = PAGE_SIZE; + + if (pshift) + psize = 1UL << pshift; + + addr &= ~(psize - 1); + radix__flush_tlb_lpid_page(kvm->arch.lpid, addr, psize); } -static void kvmppc_radix_flush_pwc(struct kvm *kvm, unsigned long addr) +static void kvmppc_radix_flush_pwc(struct kvm *kvm) { - unsigned long rb = 0x2 << PPC_BITLSHIFT(53); /* IS = 2 */ - - asm volatile("ptesync": : :"memory"); - /* RIC=1 PRS=0 R=1 IS=2 */ - asm volatile(PPC_TLBIE_5(%0, %1, 1, 0, 1) - : : "r" (rb), "r" (kvm->arch.lpid) : "memory"); - asm volatile("eieio ; tlbsync ; ptesync": : :"memory"); + radix__flush_pwc_lpid(kvm->arch.lpid); } -unsigned long kvmppc_radix_update_pte(struct kvm *kvm, pte_t *ptep, +static unsigned long kvmppc_radix_update_pte(struct kvm *kvm, pte_t *ptep, unsigned long clr, unsigned long set, unsigned long addr, unsigned int shift) { @@ -228,6 +208,167 @@ static void kvmppc_pmd_free(pmd_t *pmdp) kmem_cache_free(kvm_pmd_cache, pmdp); } +static void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte, + unsigned long gpa, unsigned int shift) + +{ + unsigned long page_size = 1ul << shift; + unsigned long old; + + old = kvmppc_radix_update_pte(kvm, pte, ~0UL, 0, gpa, shift); + kvmppc_radix_tlbie_page(kvm, gpa, shift); + if (old & _PAGE_DIRTY) { + unsigned long gfn = gpa >> PAGE_SHIFT; + struct kvm_memory_slot *memslot; + + memslot = gfn_to_memslot(kvm, gfn); + if (memslot && memslot->dirty_bitmap) + kvmppc_update_dirty_map(memslot, gfn, page_size); + } +} + +/* + * kvmppc_free_p?d are used to free existing page tables, and recursively + * descend and clear and free children. + * Callers are responsible for flushing the PWC. + * + * When page tables are being unmapped/freed as part of page fault path + * (full == false), ptes are not expected. There is code to unmap them + * and emit a warning if encountered, but there may already be data + * corruption due to the unexpected mappings. + */ +static void kvmppc_unmap_free_pte(struct kvm *kvm, pte_t *pte, bool full) +{ + if (full) { + memset(pte, 0, sizeof(long) << PTE_INDEX_SIZE); + } else { + pte_t *p = pte; + unsigned long it; + + for (it = 0; it < PTRS_PER_PTE; ++it, ++p) { + if (pte_val(*p) == 0) + continue; + WARN_ON_ONCE(1); + kvmppc_unmap_pte(kvm, p, + pte_pfn(*p) << PAGE_SHIFT, + PAGE_SHIFT); + } + } + + kvmppc_pte_free(pte); +} + +static void kvmppc_unmap_free_pmd(struct kvm *kvm, pmd_t *pmd, bool full) +{ + unsigned long im; + pmd_t *p = pmd; + + for (im = 0; im < PTRS_PER_PMD; ++im, ++p) { + if (!pmd_present(*p)) + continue; + if (pmd_is_leaf(*p)) { + if (full) { + pmd_clear(p); + } else { + WARN_ON_ONCE(1); + kvmppc_unmap_pte(kvm, (pte_t *)p, + pte_pfn(*(pte_t *)p) << PAGE_SHIFT, + PMD_SHIFT); + } + } else { + pte_t *pte; + + pte = pte_offset_map(p, 0); + kvmppc_unmap_free_pte(kvm, pte, full); + pmd_clear(p); + } + } + kvmppc_pmd_free(pmd); +} + +static void kvmppc_unmap_free_pud(struct kvm *kvm, pud_t *pud) +{ + unsigned long iu; + pud_t *p = pud; + + for (iu = 0; iu < PTRS_PER_PUD; ++iu, ++p) { + if (!pud_present(*p)) + continue; + if (pud_huge(*p)) { + pud_clear(p); + } else { + pmd_t *pmd; + + pmd = pmd_offset(p, 0); + kvmppc_unmap_free_pmd(kvm, pmd, true); + pud_clear(p); + } + } + pud_free(kvm->mm, pud); +} + +void kvmppc_free_radix(struct kvm *kvm) +{ + unsigned long ig; + pgd_t *pgd; + + if (!kvm->arch.pgtable) + return; + pgd = kvm->arch.pgtable; + for (ig = 0; ig < PTRS_PER_PGD; ++ig, ++pgd) { + pud_t *pud; + + if (!pgd_present(*pgd)) + continue; + pud = pud_offset(pgd, 0); + kvmppc_unmap_free_pud(kvm, pud); + pgd_clear(pgd); + } + pgd_free(kvm->mm, kvm->arch.pgtable); + kvm->arch.pgtable = NULL; +} + +static void kvmppc_unmap_free_pmd_entry_table(struct kvm *kvm, pmd_t *pmd, + unsigned long gpa) +{ + pte_t *pte = pte_offset_kernel(pmd, 0); + + /* + * Clearing the pmd entry then flushing the PWC ensures that the pte + * page no longer be cached by the MMU, so can be freed without + * flushing the PWC again. + */ + pmd_clear(pmd); + kvmppc_radix_flush_pwc(kvm); + + kvmppc_unmap_free_pte(kvm, pte, false); +} + +static void kvmppc_unmap_free_pud_entry_table(struct kvm *kvm, pud_t *pud, + unsigned long gpa) +{ + pmd_t *pmd = pmd_offset(pud, 0); + + /* + * Clearing the pud entry then flushing the PWC ensures that the pmd + * page and any children pte pages will no longer be cached by the MMU, + * so can be freed without flushing the PWC again. + */ + pud_clear(pud); + kvmppc_radix_flush_pwc(kvm); + + kvmppc_unmap_free_pmd(kvm, pmd, false); +} + +/* + * There are a number of bits which may differ between different faults to + * the same partition scope entry. RC bits, in the course of cleaning and + * aging. And the write bit can change, either the access could have been + * upgraded, or a read fault could happen concurrently with a write fault + * that sets those bits first. + */ +#define PTE_BITS_MUST_MATCH (~(_PAGE_WRITE | _PAGE_DIRTY | _PAGE_ACCESSED)) + static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa, unsigned int level, unsigned long mmu_seq) { @@ -235,7 +376,6 @@ static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa, pud_t *pud, *new_pud = NULL; pmd_t *pmd, *new_pmd = NULL; pte_t *ptep, *new_ptep = NULL; - unsigned long old; int ret; /* Traverse the guest's 2nd-level tree, allocate new levels needed */ @@ -273,42 +413,39 @@ static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa, if (pud_huge(*pud)) { unsigned long hgpa = gpa & PUD_MASK; + /* Check if we raced and someone else has set the same thing */ + if (level == 2) { + if (pud_raw(*pud) == pte_raw(pte)) { + ret = 0; + goto out_unlock; + } + /* Valid 1GB page here already, add our extra bits */ + WARN_ON_ONCE((pud_val(*pud) ^ pte_val(pte)) & + PTE_BITS_MUST_MATCH); + kvmppc_radix_update_pte(kvm, (pte_t *)pud, + 0, pte_val(pte), hgpa, PUD_SHIFT); + ret = 0; + goto out_unlock; + } /* * If we raced with another CPU which has just put * a 1GB pte in after we saw a pmd page, try again. */ - if (level <= 1 && !new_pmd) { + if (!new_pmd) { ret = -EAGAIN; goto out_unlock; } - /* Check if we raced and someone else has set the same thing */ - if (level == 2 && pud_raw(*pud) == pte_raw(pte)) { - ret = 0; - goto out_unlock; - } /* Valid 1GB page here already, remove it */ - old = kvmppc_radix_update_pte(kvm, (pte_t *)pud, - ~0UL, 0, hgpa, PUD_SHIFT); - kvmppc_radix_tlbie_page(kvm, hgpa, PUD_SHIFT); - if (old & _PAGE_DIRTY) { - unsigned long gfn = hgpa >> PAGE_SHIFT; - struct kvm_memory_slot *memslot; - memslot = gfn_to_memslot(kvm, gfn); - if (memslot && memslot->dirty_bitmap) - kvmppc_update_dirty_map(memslot, - gfn, PUD_SIZE); - } + kvmppc_unmap_pte(kvm, (pte_t *)pud, hgpa, PUD_SHIFT); } if (level == 2) { if (!pud_none(*pud)) { /* * There's a page table page here, but we wanted to * install a large page, so remove and free the page - * table page. new_pmd will be NULL since level == 2. + * table page. */ - new_pmd = pmd_offset(pud, 0); - pud_clear(pud); - kvmppc_radix_flush_pwc(kvm, gpa); + kvmppc_unmap_free_pud_entry_table(kvm, pud, gpa); } kvmppc_radix_set_pte_at(kvm, gpa, (pte_t *)pud, pte); ret = 0; @@ -324,42 +461,40 @@ static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa, if (pmd_is_leaf(*pmd)) { unsigned long lgpa = gpa & PMD_MASK; + /* Check if we raced and someone else has set the same thing */ + if (level == 1) { + if (pmd_raw(*pmd) == pte_raw(pte)) { + ret = 0; + goto out_unlock; + } + /* Valid 2MB page here already, add our extra bits */ + WARN_ON_ONCE((pmd_val(*pmd) ^ pte_val(pte)) & + PTE_BITS_MUST_MATCH); + kvmppc_radix_update_pte(kvm, pmdp_ptep(pmd), + 0, pte_val(pte), lgpa, PMD_SHIFT); + ret = 0; + goto out_unlock; + } + /* * If we raced with another CPU which has just put * a 2MB pte in after we saw a pte page, try again. */ - if (level == 0 && !new_ptep) { + if (!new_ptep) { ret = -EAGAIN; goto out_unlock; } - /* Check if we raced and someone else has set the same thing */ - if (level == 1 && pmd_raw(*pmd) == pte_raw(pte)) { - ret = 0; - goto out_unlock; - } /* Valid 2MB page here already, remove it */ - old = kvmppc_radix_update_pte(kvm, pmdp_ptep(pmd), - ~0UL, 0, lgpa, PMD_SHIFT); - kvmppc_radix_tlbie_page(kvm, lgpa, PMD_SHIFT); - if (old & _PAGE_DIRTY) { - unsigned long gfn = lgpa >> PAGE_SHIFT; - struct kvm_memory_slot *memslot; - memslot = gfn_to_memslot(kvm, gfn); - if (memslot && memslot->dirty_bitmap) - kvmppc_update_dirty_map(memslot, - gfn, PMD_SIZE); - } + kvmppc_unmap_pte(kvm, pmdp_ptep(pmd), lgpa, PMD_SHIFT); } if (level == 1) { if (!pmd_none(*pmd)) { /* * There's a page table page here, but we wanted to * install a large page, so remove and free the page - * table page. new_ptep will be NULL since level == 1. + * table page. */ - new_ptep = pte_offset_kernel(pmd, 0); - pmd_clear(pmd); - kvmppc_radix_flush_pwc(kvm, gpa); + kvmppc_unmap_free_pmd_entry_table(kvm, pmd, gpa); } kvmppc_radix_set_pte_at(kvm, gpa, pmdp_ptep(pmd), pte); ret = 0; @@ -378,12 +513,12 @@ static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa, ret = 0; goto out_unlock; } - /* PTE was previously valid, so invalidate it */ - old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_PRESENT, - 0, gpa, 0); - kvmppc_radix_tlbie_page(kvm, gpa, 0); - if (old & _PAGE_DIRTY) - mark_page_dirty(kvm, gpa >> PAGE_SHIFT); + /* Valid page here already, add our extra bits */ + WARN_ON_ONCE((pte_val(*ptep) ^ pte_val(pte)) & + PTE_BITS_MUST_MATCH); + kvmppc_radix_update_pte(kvm, ptep, 0, pte_val(pte), gpa, 0); + ret = 0; + goto out_unlock; } kvmppc_radix_set_pte_at(kvm, gpa, ptep, pte); ret = 0; @@ -565,9 +700,13 @@ int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, unsigned long mask = (1ul << shift) - PAGE_SIZE; pte = __pte(pte_val(pte) | (hva & mask)); } - if (!(writing || upgrade_write)) - pte = __pte(pte_val(pte) & ~ _PAGE_WRITE); - pte = __pte(pte_val(pte) | _PAGE_EXEC); + pte = __pte(pte_val(pte) | _PAGE_EXEC | _PAGE_ACCESSED); + if (writing || upgrade_write) { + if (pte_val(pte) & _PAGE_WRITE) + pte = __pte(pte_val(pte) | _PAGE_DIRTY); + } else { + pte = __pte(pte_val(pte) & ~(_PAGE_WRITE | _PAGE_DIRTY)); + } } /* Allocate space in the tree and write the PTE */ @@ -734,51 +873,6 @@ int kvmppc_init_vm_radix(struct kvm *kvm) return 0; } -void kvmppc_free_radix(struct kvm *kvm) -{ - unsigned long ig, iu, im; - pte_t *pte; - pmd_t *pmd; - pud_t *pud; - pgd_t *pgd; - - if (!kvm->arch.pgtable) - return; - pgd = kvm->arch.pgtable; - for (ig = 0; ig < PTRS_PER_PGD; ++ig, ++pgd) { - if (!pgd_present(*pgd)) - continue; - pud = pud_offset(pgd, 0); - for (iu = 0; iu < PTRS_PER_PUD; ++iu, ++pud) { - if (!pud_present(*pud)) - continue; - if (pud_huge(*pud)) { - pud_clear(pud); - continue; - } - pmd = pmd_offset(pud, 0); - for (im = 0; im < PTRS_PER_PMD; ++im, ++pmd) { - if (pmd_is_leaf(*pmd)) { - pmd_clear(pmd); - continue; - } - if (!pmd_present(*pmd)) - continue; - pte = pte_offset_map(pmd, 0); - memset(pte, 0, sizeof(long) << PTE_INDEX_SIZE); - kvmppc_pte_free(pte); - pmd_clear(pmd); - } - kvmppc_pmd_free(pmd_offset(pud, 0)); - pud_clear(pud); - } - pud_free(kvm->mm, pud_offset(pgd, 0)); - pgd_clear(pgd); - } - pgd_free(kvm->mm, kvm->arch.pgtable); - kvm->arch.pgtable = NULL; -} - static void pte_ctor(void *addr) { memset(addr, 0, RADIX_PTE_TABLE_SIZE); |