[PATCH 1 of 2] Use get page from gfn also in svm code

[Andres Lagar-Cavilla <andres@lagarcavilla.org>]

 xen/arch/x86/hvm/svm/svm.c |  20 ++++++++------------
 1 files changed, 8 insertions(+), 12 deletions(-)


And clean up some unnecessary uses of get_gfn locked.

Signed-off-by: Andres Lagar-Cavilla <andres@lagarcavilla.org>

diff -r 310e84676db3 -r 42634eca923f xen/arch/x86/hvm/svm/svm.c
--- a/xen/arch/x86/hvm/svm/svm.c
+++ b/xen/arch/x86/hvm/svm/svm.c
@@ -232,8 +232,7 @@ static int svm_vmcb_save(struct vcpu *v,
 
 static int svm_vmcb_restore(struct vcpu *v, struct hvm_hw_cpu *c)
 {
-    unsigned long mfn = 0;
-    p2m_type_t p2mt;
+    struct page_info *page = NULL;
     struct vmcb_struct *vmcb = v->arch.hvm_svm.vmcb;
     struct p2m_domain *p2m = p2m_get_hostp2m(v->domain);
 
@@ -250,10 +249,10 @@ static int svm_vmcb_restore(struct vcpu 
     {
         if ( c->cr0 & X86_CR0_PG )
         {
-            mfn = mfn_x(get_gfn(v->domain, c->cr3 >> PAGE_SHIFT, &p2mt));
-            if ( !p2m_is_ram(p2mt) || !get_page(mfn_to_page(mfn), v->domain) )
+            page = get_page_from_gfn(v->domain, c->cr3 >> PAGE_SHIFT,
+                                     NULL, P2M_ALLOC);
+            if ( !page )
             {
-                put_gfn(v->domain, c->cr3 >> PAGE_SHIFT);
                 gdprintk(XENLOG_ERR, "Invalid CR3 value=0x%"PRIx64"\n",
                          c->cr3);
                 return -EINVAL;
@@ -263,9 +262,8 @@ static int svm_vmcb_restore(struct vcpu 
         if ( v->arch.hvm_vcpu.guest_cr[0] & X86_CR0_PG )
             put_page(pagetable_get_page(v->arch.guest_table));
 
-        v->arch.guest_table = pagetable_from_pfn(mfn);
-        if ( c->cr0 & X86_CR0_PG )
-            put_gfn(v->domain, c->cr3 >> PAGE_SHIFT);
+        v->arch.guest_table = 
+            page ? pagetable_from_page(page) : pagetable_null();
     }
 
     v->arch.hvm_vcpu.guest_cr[0] = c->cr0 | X86_CR0_ET;
@@ -1321,8 +1319,7 @@ static void svm_do_nested_pgfault(struct
         p2m = p2m_get_p2m(v);
         _d.gpa = gpa;
         _d.qualification = 0;
-        mfn = get_gfn_type_access(p2m, gfn, &_d.p2mt, &p2ma, 0, NULL);
-        __put_gfn(p2m, gfn);
+        mfn = __get_gfn_type_access(p2m, gfn, &_d.p2mt, &p2ma, 0, NULL, 0);
         _d.mfn = mfn_x(mfn);
         
         __trace_var(TRC_HVM_NPF, 0, sizeof(_d), &_d);
@@ -1343,8 +1340,7 @@ static void svm_do_nested_pgfault(struct
     if ( p2m == NULL )
         p2m = p2m_get_p2m(v);
     /* Everything else is an error. */
-    mfn = get_gfn_type_access(p2m, gfn, &p2mt, &p2ma, 0, NULL);
-    __put_gfn(p2m, gfn);
+    mfn = __get_gfn_type_access(p2m, gfn, &p2mt, &p2ma, 0, NULL, 0);
     gdprintk(XENLOG_ERR,
          "SVM violation gpa %#"PRIpaddr", mfn %#lx, type %i\n",
          gpa, mfn_x(mfn), p2mt);