[xen master] arm/dom0less: introduce Kconfig for dom0less feature

[patchbot@xxxxxxx]

commit 18540a313cc66a04eb15a67d74c7992a8576fbec
Author:     Luca Fancellu <luca.fancellu@xxxxxxx>
AuthorDate: Fri Nov 24 09:48:41 2023 +0000
Commit:     Julien Grall <julien@xxxxxxx>
CommitDate: Tue Nov 28 19:21:43 2023 +0100

    arm/dom0less: introduce Kconfig for dom0less feature
    
    Introduce a Kconfig for the dom0less feature, enabled by default,
    to be able to choose if the feature should be compiled or not.
    
    Provide static inline stubs when the option is disabled for the
    functions externally visible.
    
    Use the new Kconfig to remove dom0less DT binding from the efi-boot.h
    code when the Kconfig is not enabled, do the same for
    allocate_bank_memory inside domain_build.c that currently is used
    only by dom0less-build.c module, but it's kept there provisioning
    its usage by dom0 code.
    
    Signed-off-by: Luca Fancellu <luca.fancellu@xxxxxxx>
    Reviewed-by: Michal Orzel <michal.orzel@xxxxxxx>
---
 xen/arch/arm/Kconfig                      |  8 ++++++++
 xen/arch/arm/Makefile                     |  2 +-
 xen/arch/arm/domain_build.c               |  2 ++
 xen/arch/arm/efi/efi-boot.h               |  4 ++++
 xen/arch/arm/include/asm/dom0less-build.h | 12 ++++++++++++
 xen/common/Kconfig                        |  2 +-
 6 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig
index 57dc995712..f73b62e50d 100644
--- a/xen/arch/arm/Kconfig
+++ b/xen/arch/arm/Kconfig
@@ -88,6 +88,14 @@ config GICV2
          Driver for the ARM Generic Interrupt Controller v2.
          If unsure, say Y
 
+config DOM0LESS_BOOT
+       bool "Dom0less boot support" if EXPERT
+       default y
+       help
+         Dom0less boot support enables Xen to create and start domU guests 
during
+         Xen boot without the need of a control domain (Dom0), which could be
+         present anyway.
+
 config GICV3
        bool "GICv3 driver"
        depends on !NEW_VGIC
diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile
index 2fcc3c2535..809772417c 100644
--- a/xen/arch/arm/Makefile
+++ b/xen/arch/arm/Makefile
@@ -16,7 +16,7 @@ obj-y += cpufeature.o
 obj-y += decode.o
 obj-y += device.o
 obj-$(CONFIG_IOREQ_SERVER) += dm.o
-obj-y += dom0less-build.init.o
+obj-$(CONFIG_DOM0LESS_BOOT) += dom0less-build.init.o
 obj-y += domain.o
 obj-y += domain_build.init.o
 obj-$(CONFIG_ARCH_MAP_DOMAIN_PAGE) += domain_page.o
diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 7eb766da9c..df66fb88d8 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -416,6 +416,7 @@ static void __init allocate_memory_11(struct domain *d,
     }
 }
 
+#ifdef CONFIG_DOM0LESS_BOOT
 bool __init allocate_bank_memory(struct domain *d, struct kernel_info *kinfo,
                                  gfn_t sgfn, paddr_t tot_size)
 {
@@ -477,6 +478,7 @@ bool __init allocate_bank_memory(struct domain *d, struct 
kernel_info *kinfo,
 
     return true;
 }
+#endif
 
 /*
  * When PCI passthrough is available we want to keep the
diff --git a/xen/arch/arm/efi/efi-boot.h b/xen/arch/arm/efi/efi-boot.h
index 6e6db24455..0cb29f90a0 100644
--- a/xen/arch/arm/efi/efi-boot.h
+++ b/xen/arch/arm/efi/efi-boot.h
@@ -787,6 +787,7 @@ static int __init handle_module_node(const EFI_LOADED_IMAGE 
*loaded_image,
     return 1;
 }
 
+#ifdef CONFIG_DOM0LESS_BOOT
 /*
  * This function checks for boot modules under the domU guest domain node
  * in the DT.
@@ -834,6 +835,7 @@ static int __init handle_dom0less_domain_node(const 
EFI_LOADED_IMAGE *loaded_ima
 
     return mb_modules_found;
 }
+#endif
 
 /*
  * This function checks for xen domain nodes under the /chosen node for 
possible
@@ -861,6 +863,7 @@ static int __init efi_check_dt_boot(const EFI_LOADED_IMAGE 
*loaded_image)
     {
         int ret;
 
+#ifdef CONFIG_DOM0LESS_BOOT
         if ( !fdt_node_check_compatible(fdt_efi, node, "xen,domain") )
         {
             /* Found a node with compatible xen,domain; handle this node. */
@@ -869,6 +872,7 @@ static int __init efi_check_dt_boot(const EFI_LOADED_IMAGE 
*loaded_image)
                 return ERROR_DT_MODULE_DOMU;
         }
         else
+#endif
         {
             ret = handle_module_node(loaded_image, &dir_handle, node, addr_len,
                                      size_len, false);
diff --git a/xen/arch/arm/include/asm/dom0less-build.h 
b/xen/arch/arm/include/asm/dom0less-build.h
index e027225803..5864944bda 100644
--- a/xen/arch/arm/include/asm/dom0less-build.h
+++ b/xen/arch/arm/include/asm/dom0less-build.h
@@ -5,9 +5,21 @@
 
 #include <xen/stdbool.h>
 
+#ifdef CONFIG_DOM0LESS_BOOT
+
 void create_domUs(void);
 bool is_dom0less_mode(void);
 
+#else /* !CONFIG_DOM0LESS_BOOT */
+
+static inline void create_domUs(void) {}
+static inline bool is_dom0less_mode(void)
+{
+    return false;
+}
+
+#endif /* CONFIG_DOM0LESS_BOOT */
+
 #endif /* __ASM_DOM0LESS_BUILD_H_ */
 
 /*
diff --git a/xen/common/Kconfig b/xen/common/Kconfig
index 4d6fe05164..310ad4229c 100644
--- a/xen/common/Kconfig
+++ b/xen/common/Kconfig
@@ -100,7 +100,7 @@ config NUMA
 
 config STATIC_MEMORY
        bool "Static Allocation Support (UNSUPPORTED)" if UNSUPPORTED
-       depends on ARM
+       depends on DOM0LESS_BOOT
        help
          Static Allocation refers to system or sub-system(domains) for
          which memory areas are pre-defined by configuration using physical
--
generated by git-patchbot for /home/xen/git/xen.git#master