[PATCH 08/11] types, x86 boot: define DEFINE_PTR_TYPE and char_ptr_t

[Christopher Clark <christopher.w.clark@xxxxxxxxx>]

Pointer fields within structs need to be defined as fixed size types in
the x86 boot build environment. Using a typedef for the field type
enables the definition to be changed in the 32-bit boot build and
the main hypervisor build, allowing for a single common structure
definition and a common header file.

Add a macro for defining pointer types for fields and use this macro for
pointers to chars in <xen/bootinfo.h> and <asm/bootinfo.h> as
preparation for using these headers in the x86 boot build.

The 32-bit behaviour is obtained by inclusion of "defs.h" first with a
check for such an existing definition on the <xen/types.h> version.

Signed-off-by: Christopher Clark <christopher.w.clark@xxxxxxxxx>
Signed-off-by: Daniel P. Smith <dpsmith@xxxxxxxxxxxxxxxxxxxx>

New in v2
---
 xen/arch/x86/boot/defs.h            | 4 ++++
 xen/arch/x86/include/asm/bootinfo.h | 2 +-
 xen/include/xen/bootinfo.h          | 2 +-
 xen/include/xen/types.h             | 6 ++++++
 4 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/xen/arch/x86/boot/defs.h b/xen/arch/x86/boot/defs.h
index 867df6d18d..bc0f1b5cf8 100644
--- a/xen/arch/x86/boot/defs.h
+++ b/xen/arch/x86/boot/defs.h
@@ -65,4 +65,8 @@ typedef unsigned long long paddr_t;
 #define DEFINE_STRUCT_PTR_TYPE(struct_name) \
     typedef uint64_t struct_name ## _ptr_t;
 
+#define DEFINE_PTR_TYPE(type) \
+    typedef uint64_t type ## _ptr_t;
+DEFINE_PTR_TYPE(char);
+
 #endif /* __BOOT_DEFS_H__ */
diff --git a/xen/arch/x86/include/asm/bootinfo.h 
b/xen/arch/x86/include/asm/bootinfo.h
index 8d1261503d..989fb7a1da 100644
--- a/xen/arch/x86/include/asm/bootinfo.h
+++ b/xen/arch/x86/include/asm/bootinfo.h
@@ -15,7 +15,7 @@ struct arch_boot_info {
 #define BOOTINFO_FLAG_X86_MEMMAP       1U << 6
 #define BOOTINFO_FLAG_X86_LOADERNAME   1U << 9
 
-    char *boot_loader_name;
+    char_ptr_t boot_loader_name;
 
     uint32_t mmap_length;
     paddr_t mmap_addr;
diff --git a/xen/include/xen/bootinfo.h b/xen/include/xen/bootinfo.h
index 8ee3ee36e9..8389da4f72 100644
--- a/xen/include/xen/bootinfo.h
+++ b/xen/include/xen/bootinfo.h
@@ -41,7 +41,7 @@ struct boot_module {
 DEFINE_STRUCT_PTR_TYPE(boot_module);
 
 struct boot_info {
-    char *cmdline;
+    char_ptr_t cmdline;
 
     unsigned int nr_mods;
     boot_module_ptr_t mods;
diff --git a/xen/include/xen/types.h b/xen/include/xen/types.h
index 78a2079619..e807ffe255 100644
--- a/xen/include/xen/types.h
+++ b/xen/include/xen/types.h
@@ -76,4 +76,10 @@ typedef bool bool_t;
     typedef struct struct_name * struct_name ## _ptr_t;
 #endif
 
+#ifndef DEFINE_PTR_TYPE
+#define DEFINE_PTR_TYPE(type) \
+    typedef type * type ## _ptr_t;
+DEFINE_PTR_TYPE(char);
+#endif
+
 #endif /* __TYPES_H__ */
-- 
2.25.1