Memory access and ALTP2M are two seperate features, while both depending on
helper xenmem_access_to_p2m_access(). So it betters lives in common p2m.c,
other than mem_access.c which will be compiled out when VM_EVENT=n && ALTP2M=y.
Coding style has been corrected at the same time.

Signed-off-by: Penny Zheng <Penny.Zheng@amd.com>
---
v3 -> v4:
- new commit
---
 xen/arch/x86/mm/mem_access.c | 36 ----------------------------------
 xen/arch/x86/mm/p2m.c        | 38 ++++++++++++++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 36 deletions(-)

diff --git a/xen/arch/x86/mm/mem_access.c b/xen/arch/x86/mm/mem_access.c
index e6b609064c..e55e53f44c 100644
--- a/xen/arch/x86/mm/mem_access.c
+++ b/xen/arch/x86/mm/mem_access.c
@@ -298,42 +298,6 @@ static int set_mem_access(struct domain *d, struct p2m_domain *p2m,
     return rc;
 }
 
-bool xenmem_access_to_p2m_access(const struct p2m_domain *p2m,
-                                 xenmem_access_t xaccess,
-                                 p2m_access_t *paccess)
-{
-    static const p2m_access_t memaccess[] = {
-#define ACCESS(ac) [XENMEM_access_##ac] = p2m_access_##ac
-        ACCESS(n),
-        ACCESS(r),
-        ACCESS(w),
-        ACCESS(rw),
-        ACCESS(x),
-        ACCESS(rx),
-        ACCESS(wx),
-        ACCESS(rwx),
-        ACCESS(rx2rw),
-        ACCESS(n2rwx),
-        ACCESS(r_pw),
-#undef ACCESS
-    };
-
-    switch ( xaccess )
-    {
-    case 0 ... ARRAY_SIZE(memaccess) - 1:
-        xaccess = array_index_nospec(xaccess, ARRAY_SIZE(memaccess));
-        *paccess = memaccess[xaccess];
-        break;
-    case XENMEM_access_default:
-        *paccess = p2m->default_access;
-        break;
-    default:
-        return false;
-    }
-
-    return true;
-}
-
 /*
  * Set access type for a region of gfns.
  * If gfn == INVALID_GFN, sets the default access type.
diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c
index e2a00a0efd..f2bf5ef8d3 100644
--- a/xen/arch/x86/mm/p2m.c
+++ b/xen/arch/x86/mm/p2m.c
@@ -2189,6 +2189,44 @@ void p2m_log_dirty_range(struct domain *d, unsigned long begin_pfn,
     guest_flush_tlb_mask(d, d->dirty_cpumask);
 }
 
+bool xenmem_access_to_p2m_access(const struct p2m_domain *p2m,
+                                 xenmem_access_t xaccess,
+                                 p2m_access_t *paccess)
+{
+    static const p2m_access_t memaccess[] = {
+#define ACCESS(ac) [XENMEM_access_##ac] = p2m_access_##ac
+        ACCESS(n),
+        ACCESS(r),
+        ACCESS(w),
+        ACCESS(rw),
+        ACCESS(x),
+        ACCESS(rx),
+        ACCESS(wx),
+        ACCESS(rwx),
+        ACCESS(rx2rw),
+        ACCESS(n2rwx),
+        ACCESS(r_pw),
+#undef ACCESS
+    };
+
+    switch ( xaccess )
+    {
+    case 0 ... ARRAY_SIZE(memaccess) - 1:
+        xaccess = array_index_nospec(xaccess, ARRAY_SIZE(memaccess));
+        *paccess = memaccess[xaccess];
+        break;
+
+    case XENMEM_access_default:
+        *paccess = p2m->default_access;
+        break;
+
+    default:
+        return false;
+    }
+
+    return true;
+}
+
 /*
  * Local variables:
  * mode: C
-- 
2.34.1

On 13.11.2025 04:16, Penny Zheng wrote:
> Memory access and ALTP2M are two seperate features, while both depending on
> helper xenmem_access_to_p2m_access(). So it betters lives in common p2m.c,
> other than mem_access.c which will be compiled out when VM_EVENT=n && ALTP2M=y.

Yet when both are off, the function becomes unreachable? I.e. doesn't there need
to be #ifdef around it, to please Misra?

> Coding style has been corrected at the same time.

That is, blank lines were inserted and nothing else, afaics. Could have been said
explicitly.

> Signed-off-by: Penny Zheng <Penny.Zheng@amd.com>
> ---
> v3 -> v4:
> - new commit
> ---
>  xen/arch/x86/mm/mem_access.c | 36 ----------------------------------
>  xen/arch/x86/mm/p2m.c        | 38 ++++++++++++++++++++++++++++++++++++
>  2 files changed, 38 insertions(+), 36 deletions(-)

Imo with this movement, the declaration wants to move out of mem_access.h as well.

Jan