[Xen-devel] [PATCH 08/17] xen/x86: traps: Convert show_page_walk() to use typesafe MFN

[julien@xxxxxxx]

From: Julien Grall <jgrall@xxxxxxxxxx>

Note that the code is now using cr3_to_mfn() to get the MFN. This is
slightly different as the top 12-bits will now be masked.

No functional changes intended.

Signed-off-by: Julien Grall <jgrall@xxxxxxxxxx>
---
 xen/arch/x86/x86_64/traps.c | 42 ++++++++++++++++++-------------------
 1 file changed, 21 insertions(+), 21 deletions(-)

diff --git a/xen/arch/x86/x86_64/traps.c b/xen/arch/x86/x86_64/traps.c
index c3d4faea6b..811c2cb37b 100644
--- a/xen/arch/x86/x86_64/traps.c
+++ b/xen/arch/x86/x86_64/traps.c
@@ -184,7 +184,8 @@ void vcpu_show_registers(const struct vcpu *v)
 
 void show_page_walk(unsigned long addr)
 {
-    unsigned long pfn, mfn = read_cr3() >> PAGE_SHIFT;
+    unsigned long pfn;
+    mfn_t mfn = cr3_to_mfn(read_cr3());
     l4_pgentry_t l4e, *l4t;
     l3_pgentry_t l3e, *l3t;
     l2_pgentry_t l2e, *l2t;
@@ -194,52 +195,51 @@ void show_page_walk(unsigned long addr)
     if ( !is_canonical_address(addr) )
         return;
 
-    l4t = map_domain_page(_mfn(mfn));
+    l4t = map_domain_page(mfn);
     l4e = l4t[l4_table_offset(addr)];
     unmap_domain_page(l4t);
-    mfn = l4e_get_pfn(l4e);
-    pfn = mfn_valid(_mfn(mfn)) && machine_to_phys_mapping_valid ?
-          get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY;
+    mfn = l4e_get_mfn(l4e);
+    pfn = mfn_valid(mfn) && machine_to_phys_mapping_valid ?
+          get_gpfn_from_mfn(mfn_x(mfn)) : INVALID_M2P_ENTRY;
     printk(" L4[0x%03lx] = %"PRIpte" %016lx\n",
            l4_table_offset(addr), l4e_get_intpte(l4e), pfn);
-    if ( !(l4e_get_flags(l4e) & _PAGE_PRESENT) ||
-         !mfn_valid(_mfn(mfn)) )
+    if ( !(l4e_get_flags(l4e) & _PAGE_PRESENT) || !mfn_valid(mfn) )
         return;
 
-    l3t = map_domain_page(_mfn(mfn));
+    l3t = map_domain_page(mfn);
     l3e = l3t[l3_table_offset(addr)];
     unmap_domain_page(l3t);
-    mfn = l3e_get_pfn(l3e);
-    pfn = mfn_valid(_mfn(mfn)) && machine_to_phys_mapping_valid ?
-          get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY;
+    mfn = l3e_get_mfn(l3e);
+    pfn = mfn_valid(mfn) && machine_to_phys_mapping_valid ?
+          get_gpfn_from_mfn(mfn_x(mfn)) : INVALID_M2P_ENTRY;
     printk(" L3[0x%03lx] = %"PRIpte" %016lx%s\n",
            l3_table_offset(addr), l3e_get_intpte(l3e), pfn,
            (l3e_get_flags(l3e) & _PAGE_PSE) ? " (PSE)" : "");
     if ( !(l3e_get_flags(l3e) & _PAGE_PRESENT) ||
          (l3e_get_flags(l3e) & _PAGE_PSE) ||
-         !mfn_valid(_mfn(mfn)) )
+         !mfn_valid(mfn) )
         return;
 
-    l2t = map_domain_page(_mfn(mfn));
+    l2t = map_domain_page(mfn);
     l2e = l2t[l2_table_offset(addr)];
     unmap_domain_page(l2t);
-    mfn = l2e_get_pfn(l2e);
-    pfn = mfn_valid(_mfn(mfn)) && machine_to_phys_mapping_valid ?
-          get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY;
+    mfn = l2e_get_mfn(l2e);
+    pfn = mfn_valid(mfn) && machine_to_phys_mapping_valid ?
+          get_gpfn_from_mfn(mfn_x(mfn)) : INVALID_M2P_ENTRY;
     printk(" L2[0x%03lx] = %"PRIpte" %016lx%s\n",
            l2_table_offset(addr), l2e_get_intpte(l2e), pfn,
            (l2e_get_flags(l2e) & _PAGE_PSE) ? " (PSE)" : "");
     if ( !(l2e_get_flags(l2e) & _PAGE_PRESENT) ||
          (l2e_get_flags(l2e) & _PAGE_PSE) ||
-         !mfn_valid(_mfn(mfn)) )
+         !mfn_valid(mfn) )
         return;
 
-    l1t = map_domain_page(_mfn(mfn));
+    l1t = map_domain_page(mfn);
     l1e = l1t[l1_table_offset(addr)];
     unmap_domain_page(l1t);
-    mfn = l1e_get_pfn(l1e);
-    pfn = mfn_valid(_mfn(mfn)) && machine_to_phys_mapping_valid ?
-          get_gpfn_from_mfn(mfn) : INVALID_M2P_ENTRY;
+    mfn = l1e_get_mfn(l1e);
+    pfn = mfn_valid(mfn) && machine_to_phys_mapping_valid ?
+          get_gpfn_from_mfn(mfn_x(mfn)) : INVALID_M2P_ENTRY;
     printk(" L1[0x%03lx] = %"PRIpte" %016lx\n",
            l1_table_offset(addr), l1e_get_intpte(l1e), pfn);
 }
-- 
2.17.1


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