nestedhap: Change hostcr3 and p2m->cr3 to meaningful words

VMX doesn't have the concept about host cr3 for nested p2m,
and only SVM has, so change it to netural words.

Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Acked-by: Tim Deegan <tim@xen.org>
Acked-by: Jun Nakajima <jun.nakajima@intel.com>
Acked-by: Eddie Dong <eddie.dong@intel.com>
Committed-by: Jan Beulich <jbeulich@suse.com>

3 files changed, 23 insertions, 21 deletions

diff --git a/xen/arch/x86/mm/hap/nested_hap.c b/xen/arch/x86/mm/hap/nested_hap.c
index 317875d682..9a97d366fd 100644
--- a/xen/arch/x86/mm/hap/nested_hap.c
+++ b/xen/arch/x86/mm/hap/nested_hap.c
@@ -48,9 +48,11 @@
  *    1. If #NPF is from L1 guest, then we crash the guest VM (same as old 
  *       code)
  *    2. If #NPF is from L2 guest, then we continue from (3)
- *    3. Get h_cr3 from L1 guest. Map h_cr3 into L0 hypervisor address space.
- *    4. Walk the h_cr3 page table
- *    5.    - if not present, then we inject #NPF back to L1 guest and 
+ *    3. Get np2m base from L1 guest. Map np2m base into L0 hypervisor address
+ *       space.
+ *    4. Walk the np2m's  page table
+ *    5.    - if not present or permission check failure, then we inject #NPF
+ *            back to L1 guest and
  *            re-launch L1 guest (L1 guest will either treat this #NPF as MMIO,
  *            or fix its p2m table for L2 guest)
  *    6.    - if present, then we will get the a new translated value L1-GPA 
@@ -89,7 +91,7 @@ nestedp2m_write_p2m_entry(struct p2m_domain *p2m, unsigned long gfn,
 
     if (old_flags & _PAGE_PRESENT)
         flush_tlb_mask(p2m->dirty_cpumask);
-    
+
     paging_unlock(d);
 }
 
@@ -110,7 +112,7 @@ nestedhap_fix_p2m(struct vcpu *v, struct p2m_domain *p2m,
     /* If this p2m table has been flushed or recycled under our feet, 
      * leave it alone.  We'll pick up the right one as we try to 
      * vmenter the guest. */
-    if ( p2m->cr3 == nhvm_vcpu_hostcr3(v) )
+    if ( p2m->np2m_base == nhvm_vcpu_p2m_base(v) )
     {
         unsigned long gfn, mask;
         mfn_t mfn;
@@ -186,7 +188,7 @@ nestedhap_walk_L1_p2m(struct vcpu *v, paddr_t L2_gpa, paddr_t *L1_gpa,
     uint32_t pfec;
     unsigned long nested_cr3, gfn;
     
-    nested_cr3 = nhvm_vcpu_hostcr3(v);
+    nested_cr3 = nhvm_vcpu_p2m_base(v);
 
     pfec = PFEC_user_mode | PFEC_page_present;
     if (access_w)
@@ -221,7 +223,7 @@ nestedhvm_hap_nested_page_fault(struct vcpu *v, paddr_t *L2_gpa,
     p2m_type_t p2mt_10;
 
     p2m = p2m_get_hostp2m(d); /* L0 p2m */
-    nested_p2m = p2m_get_nestedp2m(v, nhvm_vcpu_hostcr3(v));
+    nested_p2m = p2m_get_nestedp2m(v, nhvm_vcpu_p2m_base(v));
 
     /* walk the L1 P2M table */
     rv = nestedhap_walk_L1_p2m(v, *L2_gpa, &L1_gpa, &page_order_21,
diff --git a/xen/arch/x86/mm/mm-locks.h b/xen/arch/x86/mm/mm-locks.h
index 3700e32cc8..3ce3489f20 100644
--- a/xen/arch/x86/mm/mm-locks.h
+++ b/xen/arch/x86/mm/mm-locks.h
@@ -249,7 +249,7 @@ declare_mm_order_constraint(per_page_sharing)
  * A per-domain lock that protects the mapping from nested-CR3 to 
  * nested-p2m.  In particular it covers:
  * - the array of nested-p2m tables, and all LRU activity therein; and
- * - setting the "cr3" field of any p2m table to a non-CR3_EADDR value. 
+ * - setting the "cr3" field of any p2m table to a non-P2M_BASE_EAADR value.
  *   (i.e. assigning a p2m table to be the shadow of that cr3 */
 
 /* PoD lock (per-p2m-table)
diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
index 258f46e21a..41a461b55b 100644
--- a/xen/arch/x86/mm/p2m.c
+++ b/xen/arch/x86/mm/p2m.c
@@ -69,7 +69,7 @@ static void p2m_initialise(struct domain *d, struct p2m_domain *p2m)
     p2m->domain = d;
     p2m->default_access = p2m_access_rwx;
 
-    p2m->cr3 = CR3_EADDR;
+    p2m->np2m_base = P2M_BASE_EADDR;
 
     if ( hap_enabled(d) && cpu_has_vmx )
         ept_p2m_init(p2m);
@@ -1433,7 +1433,7 @@ p2m_flush_table(struct p2m_domain *p2m)
     ASSERT(page_list_empty(&p2m->pod.single));
 
     /* This is no longer a valid nested p2m for any address space */
-    p2m->cr3 = CR3_EADDR;
+    p2m->np2m_base = P2M_BASE_EADDR;
     
     /* Zap the top level of the trie */
     top = mfn_to_page(pagetable_get_mfn(p2m_get_pagetable(p2m)));
@@ -1471,7 +1471,7 @@ p2m_flush_nestedp2m(struct domain *d)
 }
 
 struct p2m_domain *
-p2m_get_nestedp2m(struct vcpu *v, uint64_t cr3)
+p2m_get_nestedp2m(struct vcpu *v, uint64_t np2m_base)
 {
     /* Use volatile to prevent gcc to cache nv->nv_p2m in a cpu register as
      * this may change within the loop by an other (v)cpu.
@@ -1480,8 +1480,8 @@ p2m_get_nestedp2m(struct vcpu *v, uint64_t cr3)
     struct domain *d;
     struct p2m_domain *p2m;
 
-    /* Mask out low bits; this avoids collisions with CR3_EADDR */
-    cr3 &= ~(0xfffull);
+    /* Mask out low bits; this avoids collisions with P2M_BASE_EADDR */
+    np2m_base &= ~(0xfffull);
 
     if (nv->nv_flushp2m && nv->nv_p2m) {
         nv->nv_p2m = NULL;
@@ -1493,14 +1493,14 @@ p2m_get_nestedp2m(struct vcpu *v, uint64_t cr3)
     if ( p2m ) 
     {
         p2m_lock(p2m);
-        if ( p2m->cr3 == cr3 || p2m->cr3 == CR3_EADDR )
+        if ( p2m->np2m_base == np2m_base || p2m->np2m_base == P2M_BASE_EADDR )
         {
             nv->nv_flushp2m = 0;
             p2m_getlru_nestedp2m(d, p2m);
             nv->nv_p2m = p2m;
-            if (p2m->cr3 == CR3_EADDR)
+            if ( p2m->np2m_base == P2M_BASE_EADDR )
                 hvm_asid_flush_vcpu(v);
-            p2m->cr3 = cr3;
+            p2m->np2m_base = np2m_base;
             cpumask_set_cpu(v->processor, p2m->dirty_cpumask);
             p2m_unlock(p2m);
             nestedp2m_unlock(d);
@@ -1515,7 +1515,7 @@ p2m_get_nestedp2m(struct vcpu *v, uint64_t cr3)
     p2m_flush_table(p2m);
     p2m_lock(p2m);
     nv->nv_p2m = p2m;
-    p2m->cr3 = cr3;
+    p2m->np2m_base = np2m_base;
     nv->nv_flushp2m = 0;
     hvm_asid_flush_vcpu(v);
     cpumask_set_cpu(v->processor, p2m->dirty_cpumask);
@@ -1531,7 +1531,7 @@ p2m_get_p2m(struct vcpu *v)
     if (!nestedhvm_is_n2(v))
         return p2m_get_hostp2m(v->domain);
 
-    return p2m_get_nestedp2m(v, nhvm_vcpu_hostcr3(v));
+    return p2m_get_nestedp2m(v, nhvm_vcpu_p2m_base(v));
 }
 
 unsigned long paging_gva_to_gfn(struct vcpu *v,
@@ -1549,15 +1549,15 @@ unsigned long paging_gva_to_gfn(struct vcpu *v,
         struct p2m_domain *p2m;
         const struct paging_mode *mode;
         uint32_t pfec_21 = *pfec;
-        uint64_t ncr3 = nhvm_vcpu_hostcr3(v);
+        uint64_t np2m_base = nhvm_vcpu_p2m_base(v);
 
         /* translate l2 guest va into l2 guest gfn */
-        p2m = p2m_get_nestedp2m(v, ncr3);
+        p2m = p2m_get_nestedp2m(v, np2m_base);
         mode = paging_get_nestedmode(v);
         gfn = mode->gva_to_gfn(v, p2m, va, pfec);
 
         /* translate l2 guest gfn into l1 guest gfn */
-        return hostmode->p2m_ga_to_gfn(v, hostp2m, ncr3,
+        return hostmode->p2m_ga_to_gfn(v, hostp2m, np2m_base,
                                        gfn << PAGE_SHIFT, &pfec_21, NULL);
     }