From 954bbbc236afe23b368abdf4942f313a5f6e1d50 Mon Sep 17 00:00:00 2001 From: Avi Kivity Date: Fri, 30 Mar 2007 14:02:32 +0300 Subject: [PATCH] KVM: Simply gfn_to_page() Mapping a guest page to a host page is a common operation. Currently, one has first to find the memory slot where the page belongs (gfn_to_memslot), then locate the page itself (gfn_to_page()). This is clumsy, and also won't work well with memory aliases. So simplify gfn_to_page() not to require memory slot translation first, and instead do it internally. Signed-off-by: Avi Kivity --- drivers/kvm/kvm.h | 12 +---------- drivers/kvm/kvm_main.c | 45 +++++++++++++++++++++++------------------- drivers/kvm/mmu.c | 12 ++++------- drivers/kvm/vmx.c | 6 +++--- 4 files changed, 33 insertions(+), 42 deletions(-) diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h index 59357bea5b61..d19985a5508a 100644 --- a/drivers/kvm/kvm.h +++ b/drivers/kvm/kvm.h @@ -443,11 +443,7 @@ void kvm_emulator_want_group7_invlpg(void); extern hpa_t bad_page_address; -static inline struct page *gfn_to_page(struct kvm_memory_slot *slot, gfn_t gfn) -{ - return slot->phys_mem[gfn - slot->base_gfn]; -} - +struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn); struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn); void mark_page_dirty(struct kvm *kvm, gfn_t gfn); @@ -523,12 +519,6 @@ static inline int kvm_mmu_page_fault(struct kvm_vcpu *vcpu, gva_t gva, return vcpu->mmu.page_fault(vcpu, gva, error_code); } -static inline struct page *_gfn_to_page(struct kvm *kvm, gfn_t gfn) -{ - struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn); - return (slot) ? slot->phys_mem[gfn - slot->base_gfn] : NULL; -} - static inline int is_long_mode(struct kvm_vcpu *vcpu) { #ifdef CONFIG_X86_64 diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c index 33eade7e237c..a0ec5dda3305 100644 --- a/drivers/kvm/kvm_main.c +++ b/drivers/kvm/kvm_main.c @@ -420,12 +420,12 @@ static int load_pdptrs(struct kvm_vcpu *vcpu, unsigned long cr3) u64 pdpte; u64 *pdpt; int ret; - struct kvm_memory_slot *memslot; + struct page *page; spin_lock(&vcpu->kvm->lock); - memslot = gfn_to_memslot(vcpu->kvm, pdpt_gfn); - /* FIXME: !memslot - emulate? 0xff? */ - pdpt = kmap_atomic(gfn_to_page(memslot, pdpt_gfn), KM_USER0); + page = gfn_to_page(vcpu->kvm, pdpt_gfn); + /* FIXME: !page - emulate? 0xff? */ + pdpt = kmap_atomic(page, KM_USER0); ret = 1; for (i = 0; i < 4; ++i) { @@ -861,6 +861,17 @@ struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn) } EXPORT_SYMBOL_GPL(gfn_to_memslot); +struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn) +{ + struct kvm_memory_slot *slot; + + slot = gfn_to_memslot(kvm, gfn); + if (!slot) + return NULL; + return slot->phys_mem[gfn - slot->base_gfn]; +} +EXPORT_SYMBOL_GPL(gfn_to_page); + void mark_page_dirty(struct kvm *kvm, gfn_t gfn) { int i; @@ -899,20 +910,20 @@ static int emulator_read_std(unsigned long addr, unsigned offset = addr & (PAGE_SIZE-1); unsigned tocopy = min(bytes, (unsigned)PAGE_SIZE - offset); unsigned long pfn; - struct kvm_memory_slot *memslot; - void *page; + struct page *page; + void *page_virt; if (gpa == UNMAPPED_GVA) return X86EMUL_PROPAGATE_FAULT; pfn = gpa >> PAGE_SHIFT; - memslot = gfn_to_memslot(vcpu->kvm, pfn); - if (!memslot) + page = gfn_to_page(vcpu->kvm, pfn); + if (!page) return X86EMUL_UNHANDLEABLE; - page = kmap_atomic(gfn_to_page(memslot, pfn), KM_USER0); + page_virt = kmap_atomic(page, KM_USER0); - memcpy(data, page + offset, tocopy); + memcpy(data, page_virt + offset, tocopy); - kunmap_atomic(page, KM_USER0); + kunmap_atomic(page_virt, KM_USER0); bytes -= tocopy; data += tocopy; @@ -963,16 +974,14 @@ static int emulator_read_emulated(unsigned long addr, static int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa, unsigned long val, int bytes) { - struct kvm_memory_slot *m; struct page *page; void *virt; if (((gpa + bytes - 1) >> PAGE_SHIFT) != (gpa >> PAGE_SHIFT)) return 0; - m = gfn_to_memslot(vcpu->kvm, gpa >> PAGE_SHIFT); - if (!m) + page = gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT); + if (!page) return 0; - page = gfn_to_page(m, gpa >> PAGE_SHIFT); kvm_mmu_pre_write(vcpu, gpa, bytes); mark_page_dirty(vcpu->kvm, gpa >> PAGE_SHIFT); virt = kmap_atomic(page, KM_USER0); @@ -2516,15 +2525,11 @@ static struct page *kvm_vm_nopage(struct vm_area_struct *vma, { struct kvm *kvm = vma->vm_file->private_data; unsigned long pgoff; - struct kvm_memory_slot *slot; struct page *page; *type = VM_FAULT_MINOR; pgoff = ((address - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; - slot = gfn_to_memslot(kvm, pgoff); - if (!slot) - return NOPAGE_SIGBUS; - page = gfn_to_page(slot, pgoff); + page = gfn_to_page(kvm, pgoff); if (!page) return NOPAGE_SIGBUS; get_page(page); diff --git a/drivers/kvm/mmu.c b/drivers/kvm/mmu.c index 376800a33968..8bdb9ca1811c 100644 --- a/drivers/kvm/mmu.c +++ b/drivers/kvm/mmu.c @@ -390,13 +390,11 @@ static void rmap_write_protect(struct kvm_vcpu *vcpu, u64 gfn) { struct kvm *kvm = vcpu->kvm; struct page *page; - struct kvm_memory_slot *slot; struct kvm_rmap_desc *desc; u64 *spte; - slot = gfn_to_memslot(kvm, gfn); - BUG_ON(!slot); - page = gfn_to_page(slot, gfn); + page = gfn_to_page(kvm, gfn); + BUG_ON(!page); while (page_private(page)) { if (!(page_private(page) & 1)) @@ -711,14 +709,12 @@ hpa_t safe_gpa_to_hpa(struct kvm_vcpu *vcpu, gpa_t gpa) hpa_t gpa_to_hpa(struct kvm_vcpu *vcpu, gpa_t gpa) { - struct kvm_memory_slot *slot; struct page *page; ASSERT((gpa & HPA_ERR_MASK) == 0); - slot = gfn_to_memslot(vcpu->kvm, gpa >> PAGE_SHIFT); - if (!slot) + page = gfn_to_page(vcpu->kvm, gpa >> PAGE_SHIFT); + if (!page) return gpa | HPA_ERR_MASK; - page = gfn_to_page(slot, gpa >> PAGE_SHIFT); return ((hpa_t)page_to_pfn(page) << PAGE_SHIFT) | (gpa & (PAGE_SIZE-1)); } diff --git a/drivers/kvm/vmx.c b/drivers/kvm/vmx.c index b64b7b792e84..61a611691e50 100644 --- a/drivers/kvm/vmx.c +++ b/drivers/kvm/vmx.c @@ -926,9 +926,9 @@ static int init_rmode_tss(struct kvm* kvm) gfn_t fn = rmode_tss_base(kvm) >> PAGE_SHIFT; char *page; - p1 = _gfn_to_page(kvm, fn++); - p2 = _gfn_to_page(kvm, fn++); - p3 = _gfn_to_page(kvm, fn); + p1 = gfn_to_page(kvm, fn++); + p2 = gfn_to_page(kvm, fn++); + p3 = gfn_to_page(kvm, fn); if (!p1 || !p2 || !p3) { kvm_printf(kvm,"%s: gfn_to_page failed\n", __FUNCTION__);