From 0d5367900a319ab8971817b0ca15a8b9f7c47e6f Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Wed, 13 May 2015 14:42:20 +0800 Subject: [PATCH] KVM: MMU: introduce for_each_rmap_spte() It's used to walk all the sptes on the rmap to clean up the code Signed-off-by: Xiao Guangrong Signed-off-by: Paolo Bonzini --- arch/x86/kvm/mmu.c | 53 ++++++++++++++-------------------------- arch/x86/kvm/mmu_audit.c | 4 +-- 2 files changed, 19 insertions(+), 38 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 44a7d2515497..7a1158533f89 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1142,6 +1142,11 @@ static u64 *rmap_get_next(struct rmap_iterator *iter) return NULL; } +#define for_each_rmap_spte(_rmap_, _iter_, _spte_) \ + for (_spte_ = rmap_get_first(*_rmap_, _iter_); \ + _spte_ && ({BUG_ON(!is_shadow_present_pte(*_spte_)); 1;}); \ + _spte_ = rmap_get_next(_iter_)) + static void drop_spte(struct kvm *kvm, u64 *sptep) { if (mmu_spte_clear_track_bits(sptep)) @@ -1205,12 +1210,8 @@ static bool __rmap_write_protect(struct kvm *kvm, unsigned long *rmapp, struct rmap_iterator iter; bool flush = false; - for (sptep = rmap_get_first(*rmapp, &iter); sptep;) { - BUG_ON(!(*sptep & PT_PRESENT_MASK)); - + for_each_rmap_spte(rmapp, &iter, sptep) flush |= spte_write_protect(kvm, sptep, pt_protect); - sptep = rmap_get_next(&iter); - } return flush; } @@ -1232,12 +1233,8 @@ static bool __rmap_clear_dirty(struct kvm *kvm, unsigned long *rmapp) struct rmap_iterator iter; bool flush = false; - for (sptep = rmap_get_first(*rmapp, &iter); sptep;) { - BUG_ON(!(*sptep & PT_PRESENT_MASK)); - + for_each_rmap_spte(rmapp, &iter, sptep) flush |= spte_clear_dirty(kvm, sptep); - sptep = rmap_get_next(&iter); - } return flush; } @@ -1259,12 +1256,8 @@ static bool __rmap_set_dirty(struct kvm *kvm, unsigned long *rmapp) struct rmap_iterator iter; bool flush = false; - for (sptep = rmap_get_first(*rmapp, &iter); sptep;) { - BUG_ON(!(*sptep & PT_PRESENT_MASK)); - + for_each_rmap_spte(rmapp, &iter, sptep) flush |= spte_set_dirty(kvm, sptep); - sptep = rmap_get_next(&iter); - } return flush; } @@ -1394,8 +1387,8 @@ static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp, WARN_ON(pte_huge(*ptep)); new_pfn = pte_pfn(*ptep); - for (sptep = rmap_get_first(*rmapp, &iter); sptep;) { - BUG_ON(!is_shadow_present_pte(*sptep)); +restart: + for_each_rmap_spte(rmapp, &iter, sptep) { rmap_printk("kvm_set_pte_rmapp: spte %p %llx gfn %llx (%d)\n", sptep, *sptep, gfn, level); @@ -1403,7 +1396,7 @@ static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp, if (pte_write(*ptep)) { drop_spte(kvm, sptep); - sptep = rmap_get_first(*rmapp, &iter); + goto restart; } else { new_spte = *sptep & ~PT64_BASE_ADDR_MASK; new_spte |= (u64)new_pfn << PAGE_SHIFT; @@ -1414,7 +1407,6 @@ static int kvm_set_pte_rmapp(struct kvm *kvm, unsigned long *rmapp, mmu_spte_clear_track_bits(sptep); mmu_spte_set(sptep, new_spte); - sptep = rmap_get_next(&iter); } } @@ -1518,16 +1510,13 @@ static int kvm_age_rmapp(struct kvm *kvm, unsigned long *rmapp, BUG_ON(!shadow_accessed_mask); - for (sptep = rmap_get_first(*rmapp, &iter); sptep; - sptep = rmap_get_next(&iter)) { - BUG_ON(!is_shadow_present_pte(*sptep)); - + for_each_rmap_spte(rmapp, &iter, sptep) if (*sptep & shadow_accessed_mask) { young = 1; clear_bit((ffs(shadow_accessed_mask) - 1), (unsigned long *)sptep); } - } + trace_kvm_age_page(gfn, level, slot, young); return young; } @@ -1548,15 +1537,11 @@ static int kvm_test_age_rmapp(struct kvm *kvm, unsigned long *rmapp, if (!shadow_accessed_mask) goto out; - for (sptep = rmap_get_first(*rmapp, &iter); sptep; - sptep = rmap_get_next(&iter)) { - BUG_ON(!is_shadow_present_pte(*sptep)); - + for_each_rmap_spte(rmapp, &iter, sptep) if (*sptep & shadow_accessed_mask) { young = 1; break; } - } out: return young; } @@ -4482,9 +4467,8 @@ static bool kvm_mmu_zap_collapsible_spte(struct kvm *kvm, pfn_t pfn; struct kvm_mmu_page *sp; - for (sptep = rmap_get_first(*rmapp, &iter); sptep;) { - BUG_ON(!(*sptep & PT_PRESENT_MASK)); - +restart: + for_each_rmap_spte(rmapp, &iter, sptep) { sp = page_header(__pa(sptep)); pfn = spte_to_pfn(*sptep); @@ -4499,10 +4483,9 @@ static bool kvm_mmu_zap_collapsible_spte(struct kvm *kvm, !kvm_is_reserved_pfn(pfn) && PageTransCompound(pfn_to_page(pfn))) { drop_spte(kvm, sptep); - sptep = rmap_get_first(*rmapp, &iter); need_tlb_flush = 1; - } else - sptep = rmap_get_next(&iter); + goto restart; + } } return need_tlb_flush; diff --git a/arch/x86/kvm/mmu_audit.c b/arch/x86/kvm/mmu_audit.c index 9ade5cfb5a4c..368d53497314 100644 --- a/arch/x86/kvm/mmu_audit.c +++ b/arch/x86/kvm/mmu_audit.c @@ -197,13 +197,11 @@ static void audit_write_protection(struct kvm *kvm, struct kvm_mmu_page *sp) rmapp = gfn_to_rmap(kvm, sp->gfn, PT_PAGE_TABLE_LEVEL); - for (sptep = rmap_get_first(*rmapp, &iter); sptep; - sptep = rmap_get_next(&iter)) { + for_each_rmap_spte(rmapp, &iter, sptep) if (is_writable_pte(*sptep)) audit_printk(kvm, "shadow page has writable " "mappings: gfn %llx role %x\n", sp->gfn, sp->role.word); - } } static void audit_sp(struct kvm *kvm, struct kvm_mmu_page *sp)