[XEN PATCH v3] x86: p2m-pod: address violation of MISRA C Rule 2.1

[Nicola Vetrini <nicola.vetrini@xxxxxxxxxxx>]

Rule 2.1 states: "A project shall not contain unreachable code".

The placement of the loop after "out_unmap" can be moved earlier
in order to avoid the unconditional return to be marked as a cause of
unreachability for the loop, as this is a consequence of
"__builtin_unreachable" being configured in ECLAIR as being deliberately
unreachable, and therefore not reported as causing the code after the
"out_unmap" label to be unreachable.

Replacing one instance of "goto out_unmap" with the loop avoids
considering the unconditional return at the end of the function as a cause
of unreachability, while preserving the semantics of the function.

No functional change intended.

Signed-off-by: Nicola Vetrini <nicola.vetrini@xxxxxxxxxxx>
---
Changes in v2:
- rebased against current staging
Changes in v3:
- move the loop inside the if and avoid one goto
---
 xen/arch/x86/mm/p2m-pod.c | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/xen/arch/x86/mm/p2m-pod.c b/xen/arch/x86/mm/p2m-pod.c
index bd84fe9e27ee..8b6f9909c5a1 100644
--- a/xen/arch/x86/mm/p2m-pod.c
+++ b/xen/arch/x86/mm/p2m-pod.c
@@ -1005,7 +1005,14 @@ p2m_pod_zero_check(struct p2m_domain *p2m, const gfn_t 
*gfns, unsigned int count
             {
                 ASSERT_UNREACHABLE();
                 domain_crash(d);
-                goto out_unmap;
+out_unmap:
+                /*
+                 * Something went wrong, probably crashing the domain.  Unmap
+                 * everything and return.
+                 */
+                for ( i = 0; i < count; i++ )
+                    if ( map[i] )
+                        unmap_domain_page(map[i]);
             }
         }
         else
@@ -1032,17 +1039,6 @@ p2m_pod_zero_check(struct p2m_domain *p2m, const gfn_t 
*gfns, unsigned int count
             ioreq_request_mapcache_invalidate(d);
         }
     }
-
-    return;
-
-out_unmap:
-    /*
-     * Something went wrong, probably crashing the domain.  Unmap
-     * everything and return.
-     */
-    for ( i = 0; i < count; i++ )
-        if ( map[i] )
-            unmap_domain_page(map[i]);
 }

 static void
--
2.43.0