[PATCH v1 2/3] xen/dom0less: refactor architecture-specific DomU construction

[Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>]

Refactor construct_domU() to improve architecture separation and reduce
reliance on ARM-specific logic in common code:
- Drop set_domain_type() from generic code. This function is specific
  to ARM and serves no purpose on other architectures like RISC-V,
  which lack the arch.type field in kernel_info.
- Introduce arch_construct_domU() to encapsulate architecture-specific
  DomU construction steps.
- Implement arch_construct_domU() for ARM. This includes:
  - Setting the domain type for CONFIG_ARM64.
  - Handling static memory allocation if xen,static-mem is present in
    the device tree.
  - Processing static shared memory.
- Move call of make_resv_memory_node() to Arm's make_arch_nodes() as
  this call is specific to CONFIG_STATIC_SHM which is ARM specific,
  at least, now.

This cleanup avoids empty stubs on other architectures and moves
ARM-specific logic into arch code where it belongs.

Also, don't loose  a return value of functions called in
Arm's make_arch_nodes().

Suggested-by: Michal Orzel <michal.orzel@xxxxxxx>
Signed-off-by: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
---
 xen/arch/arm/dom0less-build.c            | 42 +++++++++++++++++-------
 xen/common/device-tree/dom0less-build.c  | 30 ++---------------
 xen/include/asm-generic/dom0less-build.h |  3 +-
 3 files changed, 36 insertions(+), 39 deletions(-)

diff --git a/xen/arch/arm/dom0less-build.c b/xen/arch/arm/dom0less-build.c
index a49764f0ad..592173268f 100644
--- a/xen/arch/arm/dom0less-build.c
+++ b/xen/arch/arm/dom0less-build.c
@@ -220,9 +220,14 @@ int __init make_arch_nodes(struct kernel_info *kinfo)
 {
     int ret;
 
+    ret = make_resv_memory_node(kinfo, GUEST_ROOT_ADDRESS_CELLS,
+                                GUEST_ROOT_SIZE_CELLS);
+    if ( ret )
+        return ret;
+
     ret = make_psci_node(kinfo->fdt);
     if ( ret )
-        return -EINVAL;
+        return ret;
 
     if ( kinfo->arch.vpl011 )
     {
@@ -230,26 +235,41 @@ int __init make_arch_nodes(struct kernel_info *kinfo)
         ret = make_vpl011_uart_node(kinfo);
 #endif
         if ( ret )
-            return -EINVAL;
+            return ret;
     }
 
     return 0;
 }
 
-/* TODO: make arch.type generic ? */
-#ifdef CONFIG_ARM_64
-void __init set_domain_type(struct domain *d, struct kernel_info *kinfo)
+int __init arch_construct_domU(struct kernel_info *kinfo,
+                               const struct dt_device_node *node)
 {
+    int rc = 0;
+    struct domain *d = kinfo->d;
+
+#ifdef CONFIG_ARM_64
     /* type must be set before allocate memory */
     d->arch.type = kinfo->arch.type;
-}
-#else
-void __init set_domain_type(struct domain *d, struct kernel_info *kinfo)
-{
-    /* Nothing to do */
-}
 #endif
 
+    if ( !is_hardware_domain(d) )
+    {
+        if ( dt_find_property(node, "xen,static-mem", NULL) )
+        {
+            if ( !is_domain_direct_mapped(d) )
+                allocate_static_memory(d, kinfo, node);
+            else
+                assign_static_memory_11(d, kinfo, node);
+        }
+
+        rc = process_shm(d, kinfo, node);
+        if ( rc < 0 )
+            return rc;
+    }
+
+    return rc;
+}
+
 int __init init_vuart(struct domain *d, struct kernel_info *kinfo,
                       const struct dt_device_node *node)
 {
diff --git a/xen/common/device-tree/dom0less-build.c 
b/xen/common/device-tree/dom0less-build.c
index 2c56f13771..f6aabc2093 100644
--- a/xen/common/device-tree/dom0less-build.c
+++ b/xen/common/device-tree/dom0less-build.c
@@ -28,14 +28,6 @@
 #include <asm/dom0less-build.h>
 #include <asm/setup.h>
 
-#if __has_include(<asm/static-memory.h>)
-#   include <asm/static-memory.h>
-#endif
-
-#if __has_include(<asm/static-shmem.h>)
-#   include <asm/static-shmem.h>
-#endif
-
 #define XENSTORE_PFN_LATE_ALLOC UINT64_MAX
 
 static domid_t __initdata xs_domid = DOMID_INVALID;
@@ -507,12 +499,6 @@ static int __init prepare_dtb_domU(struct domain *d, 
struct kernel_info *kinfo)
     if ( ret )
         goto err;
 
-#ifdef CONFIG_STATIC_SHM
-    ret = make_resv_memory_node(kinfo, addrcells, sizecells);
-    if ( ret )
-        goto err;
-#endif
-
     /*
      * domain_handle_dtb_bootmodule has to be called before the rest of
      * the device tree is generated because it depends on the value of
@@ -787,7 +773,9 @@ static int __init construct_domU(struct domain *d,
     if ( rc < 0 )
         return rc;
 
-    set_domain_type(d, &kinfo);
+    rc = arch_construct_domU(&kinfo, node);
+    if ( rc )
+        return rc;
 
     if ( is_hardware_domain(d) )
     {
@@ -799,18 +787,6 @@ static int __init construct_domU(struct domain *d,
     {
         if ( !dt_find_property(node, "xen,static-mem", NULL) )
             allocate_memory(d, &kinfo);
-#ifdef CONFIG_STATIC_MEMORY
-        else if ( !is_domain_direct_mapped(d) )
-            allocate_static_memory(d, &kinfo, node);
-        else
-            assign_static_memory_11(d, &kinfo, node);
-#endif
-
-#ifdef CONFIG_STATIC_SHM
-        rc = process_shm(d, &kinfo, node);
-        if ( rc < 0 )
-            return rc;
-#endif
 
         rc = init_vuart(d, &kinfo, node);
         if ( rc < 0 )
diff --git a/xen/include/asm-generic/dom0less-build.h 
b/xen/include/asm-generic/dom0less-build.h
index e0ad0429ec..78142e71ca 100644
--- a/xen/include/asm-generic/dom0less-build.h
+++ b/xen/include/asm-generic/dom0less-build.h
@@ -56,7 +56,8 @@ int init_vuart(struct domain *d, struct kernel_info *kinfo,
 int make_intc_domU_node(struct kernel_info *kinfo);
 int make_arch_nodes(struct kernel_info *kinfo);
 
-void set_domain_type(struct domain *d, struct kernel_info *kinfo);
+int arch_construct_domU(struct kernel_info *kinfo,
+                        const struct dt_device_node *node);
 
 int init_intc_phandle(struct kernel_info *kinfo, const char *name,
                       const int node_next, const void *pfdt);
-- 
2.49.0