Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756002Ab0GAN46 (ORCPT ); Thu, 1 Jul 2010 09:56:58 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:57943 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752159Ab0GAN44 (ORCPT ); Thu, 1 Jul 2010 09:56:56 -0400 Message-ID: <4C2C9DC0.8050607@cn.fujitsu.com> Date: Thu, 01 Jul 2010 21:53:04 +0800 From: Xiao Guangrong User-Agent: Thunderbird 2.0.0.24 (Windows/20100228) MIME-Version: 1.0 To: Avi Kivity CC: Marcelo Tosatti , LKML , KVM list Subject: [PATCH v4 1/6] KVM: MMU: introduce gfn_to_pfn_atomic() function Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3771 Lines: 130 Introduce gfn_to_pfn_atomic(), it's the fast path and can used in atomic context, the later patch will use it Signed-off-by: Xiao Guangrong --- arch/x86/mm/gup.c | 2 ++ include/linux/kvm_host.h | 1 + virt/kvm/kvm_main.c | 32 +++++++++++++++++++++++++------- 3 files changed, 28 insertions(+), 7 deletions(-) diff --git a/arch/x86/mm/gup.c b/arch/x86/mm/gup.c index 738e659..0c9034b 100644 --- a/arch/x86/mm/gup.c +++ b/arch/x86/mm/gup.c @@ -6,6 +6,7 @@ */ #include #include +#include #include #include @@ -274,6 +275,7 @@ int __get_user_pages_fast(unsigned long start, int nr_pages, int write, return nr; } +EXPORT_SYMBOL_GPL(__get_user_pages_fast); /** * get_user_pages_fast() - pin user pages in memory diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index e796326..e0fb543 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -295,6 +295,7 @@ void kvm_release_page_dirty(struct page *page); void kvm_set_page_dirty(struct page *page); void kvm_set_page_accessed(struct page *page); +pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn); pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn); pfn_t gfn_to_pfn_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, gfn_t gfn); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index ec2e3c6..3f976b0 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -934,19 +934,25 @@ unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn) } EXPORT_SYMBOL_GPL(gfn_to_hva); -static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr) +static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr, bool atomic) { struct page *page[1]; int npages; pfn_t pfn; - might_sleep(); - - npages = get_user_pages_fast(addr, 1, 1, page); + if (atomic) + npages = __get_user_pages_fast(addr, 1, 1, page); + else { + might_sleep(); + npages = get_user_pages_fast(addr, 1, 1, page); + } if (unlikely(npages != 1)) { struct vm_area_struct *vma; + if (atomic) + goto return_bad_page; + down_read(¤t->mm->mmap_sem); if (is_hwpoison_address(addr)) { up_read(¤t->mm->mmap_sem); @@ -959,6 +965,7 @@ static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr) if (vma == NULL || addr < vma->vm_start || !(vma->vm_flags & VM_PFNMAP)) { up_read(¤t->mm->mmap_sem); +return_bad_page: get_page(bad_page); return page_to_pfn(bad_page); } @@ -972,7 +979,7 @@ static pfn_t hva_to_pfn(struct kvm *kvm, unsigned long addr) return pfn; } -pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn) +pfn_t __gfn_to_pfn(struct kvm *kvm, gfn_t gfn, bool atomic) { unsigned long addr; @@ -982,7 +989,18 @@ pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn) return page_to_pfn(bad_page); } - return hva_to_pfn(kvm, addr); + return hva_to_pfn(kvm, addr, atomic); +} + +pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn) +{ + return __gfn_to_pfn(kvm, gfn, true); +} +EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic); + +pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn) +{ + return __gfn_to_pfn(kvm, gfn, false); } EXPORT_SYMBOL_GPL(gfn_to_pfn); @@ -990,7 +1008,7 @@ pfn_t gfn_to_pfn_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, gfn_t gfn) { unsigned long addr = gfn_to_hva_memslot(slot, gfn); - return hva_to_pfn(kvm, addr); + return hva_to_pfn(kvm, addr, false); } struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn) -- 1.6.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/