[v2,02/10] KVM: introduce KVM_PFN_ERR_FAULT

Commit Message

Xiao Guangrong Aug. 3, 2012, 7:37 a.m. UTC

After that, the exported and un-inline function, get_fault_pfn,
can be removed

Signed-off-by: Xiao Guangrong <[e-mail]>
---
 arch/x86/kvm/mmu.c       |    2 +-
 include/linux/kvm_host.h |    3 ++-
 virt/kvm/kvm_main.c      |   12 +++---------
 3 files changed, 6 insertions(+), 11 deletions(-)

Comments

Avi Kivity Aug. 6, 2012, 1:01 p.m. UTC | #1

On 08/03/2012 10:37 AM, Xiao Guangrong wrote:
> After that, the exported and un-inline function, get_fault_pfn,
> can be removed
> 
> 
> +#define KVM_PFN_ERR_FAULT	(-EFAULT)
> +

IMO this symbol isn't needed, just use -EFAULT (and -EHWPOISON etc.)
directly.  Just document it in hva_to_pfn(), since this isn't an
ordinary -EFAULT (and -ENOENT certainly needs describing).

Avi Kivity Aug. 6, 2012, 1:03 p.m. UTC | #2

On 08/06/2012 04:01 PM, Avi Kivity wrote:
> On 08/03/2012 10:37 AM, Xiao Guangrong wrote:
>> After that, the exported and un-inline function, get_fault_pfn,
>> can be removed
>> 
>> 
>> +#define KVM_PFN_ERR_FAULT	(-EFAULT)
>> +
> 
> IMO this symbol isn't needed, just use -EFAULT (and -EHWPOISON etc.)
> directly.  Just document it in hva_to_pfn(), since this isn't an
> ordinary -EFAULT (and -ENOENT certainly needs describing).

Okay, I see why you did that, in patch 10.

Patch

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index a9a2052..39ed315 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -2514,7 +2514,7 @@  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)
-		return get_fault_pfn();
+		return KVM_PFN_ERR_FAULT;

 	hva = gfn_to_hva_memslot(slot, gfn);

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index dbc65f9..4c39543 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -48,6 +48,8 @@ 
 #define KVM_MAX_MMIO_FRAGMENTS \
 	(KVM_MMIO_SIZE / KVM_USER_MMIO_SIZE + KVM_EXTRA_MMIO_FRAGMENTS)

+#define KVM_PFN_ERR_FAULT	(-EFAULT)
+
 /*
  * vcpu->requests bit members
  */
@@ -444,7 +446,6 @@  void kvm_release_pfn_clean(pfn_t pfn);
 void kvm_set_pfn_dirty(pfn_t pfn);
 void kvm_set_pfn_accessed(pfn_t pfn);
 void kvm_get_pfn(pfn_t pfn);
-pfn_t get_fault_pfn(void);

 int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
 			int len);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index bcf973e..9c084f8 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -948,12 +948,6 @@  static pfn_t get_bad_pfn(void)
 	return -ENOENT;
 }

-pfn_t get_fault_pfn(void)
-{
-	return -EFAULT;
-}
-EXPORT_SYMBOL_GPL(get_fault_pfn);
-
 static pfn_t get_hwpoison_pfn(void)
 {
 	return -EHWPOISON;
@@ -1124,7 +1118,7 @@  static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
 		struct vm_area_struct *vma;

 		if (atomic)
-			return get_fault_pfn();
+			return KVM_PFN_ERR_FAULT;

 		down_read(&current->mm->mmap_sem);
 		if (npages == -EHWPOISON ||
@@ -1136,7 +1130,7 @@  static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
 		vma = find_vma_intersection(current->mm, addr, addr+1);

 		if (vma == NULL)
-			pfn = get_fault_pfn();
+			pfn = KVM_PFN_ERR_FAULT;
 		else if ((vma->vm_flags & VM_PFNMAP)) {
 			pfn = ((addr - vma->vm_start) >> PAGE_SHIFT) +
 				vma->vm_pgoff;
@@ -1144,7 +1138,7 @@  static pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async,
 		} else {
 			if (async && (vma->vm_flags & VM_WRITE))
 				*async = true;
-			pfn = get_fault_pfn();
+			pfn = KVM_PFN_ERR_FAULT;
 		}
 		up_read(&current->mm->mmap_sem);
 	} else