[PATCH v3 15/52] xen: make VMAP only support in MMU system

[Penny Zheng <Penny.Zheng@xxxxxxx>]

VMAP is widely used in ALTERNATIVE feature, CPUERRATA feature, Grant
Table feature, LIVEPATCH feature etc, to remap a range of memory with new
memory attributes. Since this is highly dependent on virtual address
translation, we choose to fold VMAP in MMU system.

In this patch, we introduce a new Kconfig CONFIG_HAS_VMAP, and make it only
support in MMU system on ARM architecture. And we make features like
ALTERNATIVE, CPUERRATA, LIVEPATCH, Grant Table, etc, now depend on VMAP.

Signed-off-by: Penny Zheng <penny.zheng@xxxxxxx>
Signed-off-by: Wei Chen <wei.chen@xxxxxxx>
---
v2:
- new commit
---
v3:
- make LIVEPATCH/ALTERNATIVE/CPUERRATA/Grant Table/LIVEPATCH depend on HAS_VMAP
- function call should be wrapped in context, then we could remove inline stubs
---
 xen/arch/arm/Kconfig   |  3 ++-
 xen/arch/arm/Makefile  |  2 +-
 xen/arch/arm/setup.c   |  7 +++++++
 xen/arch/arm/smpboot.c |  2 ++
 xen/arch/x86/Kconfig   |  1 +
 xen/arch/x86/setup.c   |  2 ++
 xen/common/Kconfig     |  5 +++++
 xen/common/Makefile    |  2 +-
 xen/common/vmap.c      |  7 +++++++
 xen/include/xen/vmap.h | 11 ++++-------
 10 files changed, 32 insertions(+), 10 deletions(-)

diff --git a/xen/arch/arm/Kconfig b/xen/arch/arm/Kconfig
index 22b28b8ba2..a88500fb50 100644
--- a/xen/arch/arm/Kconfig
+++ b/xen/arch/arm/Kconfig
@@ -11,7 +11,7 @@ config ARM_64
 
 config ARM
        def_bool y
-       select HAS_ALTERNATIVE
+       select HAS_ALTERNATIVE if HAS_VMAP
        select HAS_DEVICE_TREE
        select HAS_PASSTHROUGH
        select HAS_PDX
@@ -63,6 +63,7 @@ config HAS_MMU
        bool "Memory Management Unit support in a VMSA system"
        default y
        select HAS_PMAP
+       select HAS_VMAP
        help
          In a VMSA system, a Memory Management Unit (MMU) provides 
fine-grained control of
          a memory system through a set of virtual to physical address mappings 
and associated memory
diff --git a/xen/arch/arm/Makefile b/xen/arch/arm/Makefile
index c1babdba6a..d01528cac6 100644
--- a/xen/arch/arm/Makefile
+++ b/xen/arch/arm/Makefile
@@ -10,7 +10,7 @@ obj-$(CONFIG_HAS_VPCI) += vpci.o
 
 obj-$(CONFIG_HAS_ALTERNATIVE) += alternative.o
 obj-y += bootfdt.init.o
-obj-y += cpuerrata.o
+obj-$(CONFIG_HAS_VMAP) += cpuerrata.o
 obj-y += cpufeature.o
 obj-y += decode.o
 obj-y += device.o
diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
index 50259552a0..34923d9984 100644
--- a/xen/arch/arm/setup.c
+++ b/xen/arch/arm/setup.c
@@ -812,7 +812,9 @@ void __init start_xen(unsigned long boot_phys_offset,
      */
     system_state = SYS_STATE_boot;
 
+#ifdef CONFIG_HAS_VMAP
     vm_init();
+#endif
 
     if ( acpi_disabled )
     {
@@ -844,11 +846,13 @@ void __init start_xen(unsigned long boot_phys_offset,
     nr_cpu_ids = smp_get_max_cpus();
     printk(XENLOG_INFO "SMP: Allowing %u CPUs\n", nr_cpu_ids);
 
+#ifdef CONFIG_HAS_VMAP
     /*
      * Some errata relies on SMCCC version which is detected by psci_init()
      * (called from smp_init_cpus()).
      */
     check_local_cpu_errata();
+#endif
 
     check_local_cpu_features();
 
@@ -915,12 +919,15 @@ void __init start_xen(unsigned long boot_phys_offset,
 
     do_initcalls();
 
+
+#ifdef CONFIG_HAS_VMAP
     /*
      * It needs to be called after do_initcalls to be able to use
      * stop_machine (tasklets initialized via an initcall).
      */
     apply_alternatives_all();
     enable_errata_workarounds();
+#endif
     enable_cpu_features();
 
     /* Create initial domain 0. */
diff --git a/xen/arch/arm/smpboot.c b/xen/arch/arm/smpboot.c
index 8bcdbea66c..0796e534ec 100644
--- a/xen/arch/arm/smpboot.c
+++ b/xen/arch/arm/smpboot.c
@@ -388,7 +388,9 @@ void start_secondary(void)
 
     local_abort_enable();
 
+#ifdef CONFIG_HAS_VMAP
     check_local_cpu_errata();
+#endif
     check_local_cpu_features();
 
     printk(XENLOG_DEBUG "CPU %u booted.\n", smp_processor_id());
diff --git a/xen/arch/x86/Kconfig b/xen/arch/x86/Kconfig
index 406445a358..033cc2332e 100644
--- a/xen/arch/x86/Kconfig
+++ b/xen/arch/x86/Kconfig
@@ -27,6 +27,7 @@ config X86
        select HAS_PDX
        select HAS_SCHED_GRANULARITY
        select HAS_UBSAN
+       select HAS_VMAP
        select HAS_VPCI if HVM
        select NEEDS_LIBELF
 
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index 74e3915a4d..9f06879225 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -1750,12 +1750,14 @@ void __init noreturn __start_xen(unsigned long mbi_p)
         end_boot_allocator();
 
     system_state = SYS_STATE_boot;
+#ifdef CONFIG_HAS_VMAP
     /*
      * No calls involving ACPI code should go between the setting of
      * SYS_STATE_boot and vm_init() (or else acpi_os_{,un}map_memory()
      * will break).
      */
     vm_init();
+#endif
 
     bsp_stack = cpu_alloc_stack(0);
     if ( !bsp_stack )
diff --git a/xen/common/Kconfig b/xen/common/Kconfig
index 3d2123a783..2c29e89b75 100644
--- a/xen/common/Kconfig
+++ b/xen/common/Kconfig
@@ -15,6 +15,7 @@ config CORE_PARKING
 config GRANT_TABLE
        bool "Grant table support" if EXPERT
        default y
+       depends on HAS_VMAP
        ---help---
          Grant table provides a generic mechanism to memory sharing
          between domains. This shared memory interface underpins the
@@ -65,6 +66,9 @@ config HAS_SCHED_GRANULARITY
 config HAS_UBSAN
        bool
 
+config HAS_VMAP
+       bool
+
 config MEM_ACCESS_ALWAYS_ON
        bool
 
@@ -367,6 +371,7 @@ config LIVEPATCH
        bool "Live patching support"
        default X86
        depends on "$(XEN_HAS_BUILD_ID)" = "y"
+       depends on HAS_VMAP
        select CC_SPLIT_SECTIONS
        ---help---
          Allows a running Xen hypervisor to be dynamically patched using
diff --git a/xen/common/Makefile b/xen/common/Makefile
index 46049eac35..4803282d62 100644
--- a/xen/common/Makefile
+++ b/xen/common/Makefile
@@ -51,7 +51,7 @@ obj-$(CONFIG_TRACEBUFFER) += trace.o
 obj-y += version.o
 obj-y += virtual_region.o
 obj-y += vm_event.o
-obj-y += vmap.o
+obj-$(CONFIG_HAS_VMAP) += vmap.o
 obj-y += vsprintf.o
 obj-y += wait.o
 obj-bin-y += warning.init.o
diff --git a/xen/common/vmap.c b/xen/common/vmap.c
index 4fd6b3067e..51e13e17ed 100644
--- a/xen/common/vmap.c
+++ b/xen/common/vmap.c
@@ -331,4 +331,11 @@ void vfree(void *va)
     while ( (pg = page_list_remove_head(&pg_list)) != NULL )
         free_domheap_page(pg);
 }
+
+void iounmap(void __iomem *va)
+{
+    unsigned long addr = (unsigned long)(void __force *)va;
+
+    vunmap((void *)(addr & PAGE_MASK));
+}
 #endif
diff --git a/xen/include/xen/vmap.h b/xen/include/xen/vmap.h
index b0f7632e89..d7ef4df452 100644
--- a/xen/include/xen/vmap.h
+++ b/xen/include/xen/vmap.h
@@ -1,4 +1,4 @@
-#if !defined(__XEN_VMAP_H__) && defined(VMAP_VIRT_START)
+#if !defined(__XEN_VMAP_H__) && (defined(VMAP_VIRT_START) || 
!defined(CONFIG_HAS_VMAP))
 #define __XEN_VMAP_H__
 
 #include <xen/mm-frame.h>
@@ -25,17 +25,14 @@ void vfree(void *va);
 
 void __iomem *ioremap(paddr_t, size_t);
 
-static inline void iounmap(void __iomem *va)
-{
-    unsigned long addr = (unsigned long)(void __force *)va;
-
-    vunmap((void *)(addr & PAGE_MASK));
-}
+void iounmap(void __iomem *va);
 
 void *arch_vmap_virt_end(void);
 static inline void vm_init(void)
 {
+#if defined(VMAP_VIRT_START)
     vm_init_type(VMAP_DEFAULT, (void *)VMAP_VIRT_START, arch_vmap_virt_end());
+#endif
 }
 
 #endif /* __XEN_VMAP_H__ */
-- 
2.25.1