On Thu, Jun 30, 2011 at 04:24:06PM +0800, Xiao Guangrong wrote: > If the page fault is caused by mmio, the gfn can not be found in memslots, and > 'bad_pfn' is returned on gfn_to_hva path, so we can use 'bad_pfn' to identify > the mmio page fault. > And, to clarify the meaning of mmio pfn, we return fault page instead of bad > page when the gfn is not allowd to prefetch > > Signed-off-by: Xiao Guangrong <xiaoguangrong@xxxxxxxxxxxxxx> > --- > arch/x86/kvm/mmu.c | 4 ++-- > include/linux/kvm_host.h | 5 +++++ > virt/kvm/kvm_main.c | 16 ++++++++++++++-- > 3 files changed, 21 insertions(+), 4 deletions(-) > > diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c > index 5334b4e..96a7ed4 100644 > --- a/arch/x86/kvm/mmu.c > +++ b/arch/x86/kvm/mmu.c > @@ -2085,8 +2085,8 @@ static pfn_t pte_prefetch_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn, > > slot = gfn_to_memslot_dirty_bitmap(vcpu, gfn, no_dirty_log); > if (!slot) { > - get_page(bad_page); > - return page_to_pfn(bad_page); > + get_page(fault_page); > + return page_to_pfn(fault_page); > } > > hva = gfn_to_hva_memslot(slot, gfn); > diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h > index 31ebb59..3e548e8 100644 > --- a/include/linux/kvm_host.h > +++ b/include/linux/kvm_host.h > @@ -326,12 +326,17 @@ static inline struct kvm_memslots *kvm_memslots(struct kvm *kvm) > static inline int is_error_hpa(hpa_t hpa) { return hpa >> HPA_MSB; } > > extern struct page *bad_page; > +extern struct page *fault_page; > + > extern pfn_t bad_pfn; > +extern pfn_t fault_pfn; > > int is_error_page(struct page *page); > int is_error_pfn(pfn_t pfn); > int is_hwpoison_pfn(pfn_t pfn); > int is_fault_pfn(pfn_t pfn); > +int is_mmio_pfn(pfn_t pfn); > +int is_invalid_pfn(pfn_t pfn); > int kvm_is_error_hva(unsigned long addr); > int kvm_set_memory_region(struct kvm *kvm, > struct kvm_userspace_memory_region *mem, > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index 11d2783..c7d41d4 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -101,8 +101,8 @@ static bool largepages_enabled = true; > static struct page *hwpoison_page; > static pfn_t hwpoison_pfn; > > -static struct page *fault_page; > -static pfn_t fault_pfn; > +struct page *fault_page; > +pfn_t fault_pfn; > > inline int kvm_is_mmio_pfn(pfn_t pfn) > { > @@ -931,6 +931,18 @@ int is_fault_pfn(pfn_t pfn) > } > EXPORT_SYMBOL_GPL(is_fault_pfn); > > +int is_mmio_pfn(pfn_t pfn) > +{ > + return pfn == bad_pfn; > +} > +EXPORT_SYMBOL_GPL(is_mmio_pfn); Please use another name this conflicts with real mmio pfn, see kvm_is_mmio_pfn. "noslot_pfn" is meaningful to me. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html