2015-04-02 12:08:30

by Paolo Bonzini

Subject: [PATCH] KVM: remove kvm_read_hva and kvm_read_hva_atomic

The corresponding write functions just use __copy_to_user. Do the
same on the read side.

This reverts what's left of commit 86ab8cffb498 (KVM: introduce
gfn_to_hva_read/kvm_read_hva/kvm_read_hva_atomic, 2012-08-21)

Cc: Xiao Guangrong <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
---
virt/kvm/kvm_main.c | 14 ++------------
1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index a1093700f3a4..c772c31a87bb 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1193,16 +1193,6 @@ unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable)
return gfn_to_hva_memslot_prot(slot, gfn, writable);
}

-static int kvm_read_hva(void *data, void __user *hva, int len)
-{
- return __copy_from_user(data, hva, len);
-}
-
-static int kvm_read_hva_atomic(void *data, void __user *hva, int len)
-{
- return __copy_from_user_inatomic(data, hva, len);
-}
-
static int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm,
unsigned long start, int write, struct page **page)
{
@@ -1554,7 +1544,7 @@ int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
addr = gfn_to_hva_prot(kvm, gfn, NULL);
if (kvm_is_error_hva(addr))
return -EFAULT;
- r = kvm_read_hva(data, (void __user *)addr + offset, len);
+ r = __copy_from_user(data, (void __user *)addr + offset, len);
if (r)
return -EFAULT;
return 0;
@@ -1593,7 +1583,7 @@ int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data,
if (kvm_is_error_hva(addr))
return -EFAULT;
pagefault_disable();
- r = kvm_read_hva_atomic(data, (void __user *)addr + offset, len);
+ r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
pagefault_enable();
if (r)
return -EFAULT;
--
2.3.4

2015-04-03 04:09:38

by Xiao Guangrong

Subject: Re: [PATCH] KVM: remove kvm_read_hva and kvm_read_hva_atomic

On 04/02/2015 08:08 PM, Paolo Bonzini wrote:
> The corresponding write functions just use __copy_to_user. Do the
> same on the read side.
>
> This reverts what's left of commit 86ab8cffb498 (KVM: introduce
> gfn_to_hva_read/kvm_read_hva/kvm_read_hva_atomic, 2012-08-21)
>

It looks good to me.

Reviewed-by: Xiao Guangrong <[email protected]>