diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_64_mmu_radix.c')
-rw-r--r-- | arch/powerpc/kvm/book3s_64_mmu_radix.c | 107 |
1 files changed, 68 insertions, 39 deletions
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c index aa41183d2a97..3cb0c9843d01 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c @@ -11,12 +11,12 @@ #include <linux/anon_inodes.h> #include <linux/file.h> #include <linux/debugfs.h> +#include <linux/pgtable.h> #include <asm/kvm_ppc.h> #include <asm/kvm_book3s.h> #include <asm/page.h> #include <asm/mmu.h> -#include <asm/pgtable.h> #include <asm/pgalloc.h> #include <asm/pte-walk.h> #include <asm/ultravisor.h> @@ -514,13 +514,14 @@ void kvmppc_free_pgtable_radix(struct kvm *kvm, pgd_t *pgd, unsigned int lpid) unsigned long ig; for (ig = 0; ig < PTRS_PER_PGD; ++ig, ++pgd) { + p4d_t *p4d = p4d_offset(pgd, 0); pud_t *pud; - if (!pgd_present(*pgd)) + if (!p4d_present(*p4d)) continue; - pud = pud_offset(pgd, 0); + pud = pud_offset(p4d, 0); kvmppc_unmap_free_pud(kvm, pud, lpid); - pgd_clear(pgd); + p4d_clear(p4d); } } @@ -581,6 +582,7 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte, unsigned long *rmapp, struct rmap_nested **n_rmap) { pgd_t *pgd; + p4d_t *p4d; pud_t *pud, *new_pud = NULL; pmd_t *pmd, *new_pmd = NULL; pte_t *ptep, *new_ptep = NULL; @@ -588,9 +590,11 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte, /* Traverse the guest's 2nd-level tree, allocate new levels needed */ pgd = pgtable + pgd_index(gpa); + p4d = p4d_offset(pgd, gpa); + pud = NULL; - if (pgd_present(*pgd)) - pud = pud_offset(pgd, gpa); + if (p4d_present(*p4d)) + pud = pud_offset(p4d, gpa); else new_pud = pud_alloc_one(kvm->mm, gpa); @@ -611,13 +615,13 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte, /* Now traverse again under the lock and change the tree */ ret = -ENOMEM; - if (pgd_none(*pgd)) { + if (p4d_none(*p4d)) { if (!new_pud) goto out_unlock; - pgd_populate(kvm->mm, pgd, new_pud); + p4d_populate(kvm->mm, p4d, new_pud); new_pud = NULL; } - pud = pud_offset(pgd, gpa); + pud = pud_offset(p4d, gpa); if (pud_is_leaf(*pud)) { unsigned long hgpa = gpa & PUD_MASK; @@ -750,7 +754,7 @@ int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte, return ret; } -bool kvmppc_hv_handle_set_rc(struct kvm *kvm, pgd_t *pgtable, bool writing, +bool kvmppc_hv_handle_set_rc(struct kvm *kvm, bool nested, bool writing, unsigned long gpa, unsigned int lpid) { unsigned long pgflags; @@ -765,12 +769,12 @@ bool kvmppc_hv_handle_set_rc(struct kvm *kvm, pgd_t *pgtable, bool writing, pgflags = _PAGE_ACCESSED; if (writing) pgflags |= _PAGE_DIRTY; - /* - * We are walking the secondary (partition-scoped) page table here. - * We can do this without disabling irq because the Linux MM - * subsystem doesn't do THP splits and collapses on this tree. - */ - ptep = __find_linux_pte(pgtable, gpa, NULL, &shift); + + if (nested) + ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift); + else + ptep = find_kvm_secondary_pte(kvm, gpa, &shift); + if (ptep && pte_present(*ptep) && (!writing || pte_write(*ptep))) { kvmppc_radix_update_pte(kvm, ptep, 0, pgflags, gpa, shift); return true; @@ -806,7 +810,7 @@ int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu, * is that the page is writable. */ hva = gfn_to_hva_memslot(memslot, gfn); - if (!kvm_ro && __get_user_pages_fast(hva, 1, 1, &page) == 1) { + if (!kvm_ro && get_user_page_fast_only(hva, FOLL_WRITE, &page)) { upgrade_write = true; } else { unsigned long pfn; @@ -828,12 +832,12 @@ int kvmppc_book3s_instantiate_page(struct kvm_vcpu *vcpu, * Read the PTE from the process' radix tree and use that * so we get the shift and attribute bits. */ - local_irq_disable(); - ptep = __find_linux_pte(vcpu->arch.pgdir, hva, NULL, &shift); + spin_lock(&kvm->mmu_lock); + ptep = find_kvm_host_pte(kvm, mmu_seq, hva, &shift); pte = __pte(0); if (ptep) - pte = *ptep; - local_irq_enable(); + pte = READ_ONCE(*ptep); + spin_unlock(&kvm->mmu_lock); /* * If the PTE disappeared temporarily due to a THP * collapse, just return and let the guest try again. @@ -964,8 +968,8 @@ int kvmppc_book3s_radix_page_fault(struct kvm_vcpu *vcpu, /* Failed to set the reference/change bits */ if (dsisr & DSISR_SET_RC) { spin_lock(&kvm->mmu_lock); - if (kvmppc_hv_handle_set_rc(kvm, kvm->arch.pgtable, - writing, gpa, kvm->arch.lpid)) + if (kvmppc_hv_handle_set_rc(kvm, false, writing, + gpa, kvm->arch.lpid)) dsisr &= ~DSISR_SET_RC; spin_unlock(&kvm->mmu_lock); @@ -996,11 +1000,11 @@ int kvm_unmap_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, return 0; } - ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift); + ptep = find_kvm_secondary_pte(kvm, gpa, &shift); if (ptep && pte_present(*ptep)) kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot, kvm->arch.lpid); - return 0; + return 0; } /* Called with kvm->mmu_lock held */ @@ -1016,7 +1020,7 @@ int kvm_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) return ref; - ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift); + ptep = find_kvm_secondary_pte(kvm, gpa, &shift); if (ptep && pte_present(*ptep) && pte_young(*ptep)) { old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_ACCESSED, 0, gpa, shift); @@ -1043,7 +1047,7 @@ int kvm_test_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot, if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) return ref; - ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift); + ptep = find_kvm_secondary_pte(kvm, gpa, &shift); if (ptep && pte_present(*ptep) && pte_young(*ptep)) ref = 1; return ref; @@ -1055,7 +1059,7 @@ static int kvm_radix_test_clear_dirty(struct kvm *kvm, { unsigned long gfn = memslot->base_gfn + pagenum; unsigned long gpa = gfn << PAGE_SHIFT; - pte_t *ptep; + pte_t *ptep, pte; unsigned int shift; int ret = 0; unsigned long old, *rmapp; @@ -1063,12 +1067,35 @@ static int kvm_radix_test_clear_dirty(struct kvm *kvm, if (kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE) return ret; - ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift); - if (ptep && pte_present(*ptep) && pte_dirty(*ptep)) { - ret = 1; - if (shift) - ret = 1 << (shift - PAGE_SHIFT); + /* + * For performance reasons we don't hold kvm->mmu_lock while walking the + * partition scoped table. + */ + ptep = find_kvm_secondary_pte_unlocked(kvm, gpa, &shift); + if (!ptep) + return 0; + + pte = READ_ONCE(*ptep); + if (pte_present(pte) && pte_dirty(pte)) { spin_lock(&kvm->mmu_lock); + /* + * Recheck the pte again + */ + if (pte_val(pte) != pte_val(*ptep)) { + /* + * We have KVM_MEM_LOG_DIRTY_PAGES enabled. Hence we can + * only find PAGE_SIZE pte entries here. We can continue + * to use the pte addr returned by above page table + * walk. + */ + if (!pte_present(*ptep) || !pte_dirty(*ptep)) { + spin_unlock(&kvm->mmu_lock); + return 0; + } + } + + ret = 1; + VM_BUG_ON(shift); old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_DIRTY, 0, gpa, shift); kvmppc_radix_tlbie_page(kvm, gpa, shift, kvm->arch.lpid); @@ -1124,7 +1151,7 @@ void kvmppc_radix_flush_memslot(struct kvm *kvm, gpa = memslot->base_gfn << PAGE_SHIFT; spin_lock(&kvm->mmu_lock); for (n = memslot->npages; n; --n) { - ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift); + ptep = find_kvm_secondary_pte(kvm, gpa, &shift); if (ptep && pte_present(*ptep)) kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot, kvm->arch.lpid); @@ -1240,7 +1267,8 @@ static ssize_t debugfs_radix_read(struct file *file, char __user *buf, unsigned long gpa; pgd_t *pgt; struct kvm_nested_guest *nested; - pgd_t pgd, *pgdp; + pgd_t *pgdp; + p4d_t p4d, *p4dp; pud_t pud, *pudp; pmd_t pmd, *pmdp; pte_t *ptep; @@ -1313,13 +1341,14 @@ static ssize_t debugfs_radix_read(struct file *file, char __user *buf, } pgdp = pgt + pgd_index(gpa); - pgd = READ_ONCE(*pgdp); - if (!(pgd_val(pgd) & _PAGE_PRESENT)) { - gpa = (gpa & PGDIR_MASK) + PGDIR_SIZE; + p4dp = p4d_offset(pgdp, gpa); + p4d = READ_ONCE(*p4dp); + if (!(p4d_val(p4d) & _PAGE_PRESENT)) { + gpa = (gpa & P4D_MASK) + P4D_SIZE; continue; } - pudp = pud_offset(&pgd, gpa); + pudp = pud_offset(&p4d, gpa); pud = READ_ONCE(*pudp); if (!(pud_val(pud) & _PAGE_PRESENT)) { gpa = (gpa & PUD_MASK) + PUD_SIZE; |