To allow generic code to remap memory as read-only, let's add the
definition to the global header.

On platforms other than ARM, mapping R/O will just be cached R/W.

Signed-off-by: Ahmad Fatoum <[email protected]>
---
 arch/Kconfig              | 3 +++
 arch/arm/Kconfig          | 1 +
 arch/arm/cpu/mmu-common.c | 4 ++--
 arch/arm/cpu/mmu-common.h | 3 +--
 arch/arm/cpu/mmu_32.c     | 4 ++--
 arch/arm/cpu/mmu_64.c     | 2 +-
 include/mmu.h             | 6 ++++++
 7 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/arch/Kconfig b/arch/Kconfig
index ca9aa25a9c4b..3daba5239740 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -62,6 +62,9 @@ config ARCH_DMA_DEFAULT_COHERENT
 config ARCH_HAS_DMA_WRITE_COMBINE
        bool
 
+config ARCH_HAS_RO_MAPPINGS
+       bool
+
 config ARCH_HAS_ASAN_FIBER_API
        bool
 
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 5123e9b1402c..d9b1f5de1fa7 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -17,6 +17,7 @@ config ARM
        select HAVE_ARCH_BOOTM_OFTREE
        select HW_HAS_PCI
        select ARCH_HAS_DMA_WRITE_COMBINE
+       select ARCH_HAS_RO_MAPPINGS
        select HAVE_EFI_LOADER if MMU # for payload unaligned accesses
        default y
 
diff --git a/arch/arm/cpu/mmu-common.c b/arch/arm/cpu/mmu-common.c
index a1431c0ff461..6db85fa9c7d4 100644
--- a/arch/arm/cpu/mmu-common.c
+++ b/arch/arm/cpu/mmu-common.c
@@ -22,7 +22,7 @@ const char *map_type_tostr(maptype_t map_type)
 
        switch (map_type) {
        case ARCH_MAP_CACHED_RWX:       return "RWX";
-       case ARCH_MAP_CACHED_RO:        return "RO";
+       case MAP_RO:                    return "RO";
        case MAP_CACHED:                return "CACHED";
        case MAP_UNCACHED:              return "UNCACHED";
        case MAP_CODE:                  return "CODE";
@@ -158,7 +158,7 @@ static void mmu_remap_memory_banks(void)
        }
 
        remap_range((void *)code_start, code_size, MAP_CODE);
-       remap_range((void *)rodata_start, rodata_size, ARCH_MAP_CACHED_RO);
+       remap_range((void *)rodata_start, rodata_size, MAP_RO);
 
        setup_trap_pages();
 }
diff --git a/arch/arm/cpu/mmu-common.h b/arch/arm/cpu/mmu-common.h
index a111e15a21b4..39332d8f5a98 100644
--- a/arch/arm/cpu/mmu-common.h
+++ b/arch/arm/cpu/mmu-common.h
@@ -12,7 +12,6 @@
 #include <linux/bits.h>
 
 #define ARCH_MAP_CACHED_RWX    MAP_ARCH(2)
-#define ARCH_MAP_CACHED_RO     MAP_ARCH(3)
 
 #define ARCH_MAP_FLAG_PAGEWISE BIT(31)
 
@@ -32,7 +31,7 @@ static inline maptype_t 
arm_mmu_maybe_skip_permissions(maptype_t map_type)
        switch (map_type & MAP_TYPE_MASK) {
        case MAP_CODE:
        case MAP_CACHED:
-       case ARCH_MAP_CACHED_RO:
+       case MAP_RO:
                return ARCH_MAP_CACHED_RWX;
        default:
                return map_type;
diff --git a/arch/arm/cpu/mmu_32.c b/arch/arm/cpu/mmu_32.c
index 912d14e8cf82..d41ebcfb7fe4 100644
--- a/arch/arm/cpu/mmu_32.c
+++ b/arch/arm/cpu/mmu_32.c
@@ -304,7 +304,7 @@ static uint32_t get_pte_flags(maptype_t map_type)
                switch (map_type & MAP_TYPE_MASK) {
                case ARCH_MAP_CACHED_RWX:
                        return PTE_FLAGS_CACHED_V7_RWX;
-               case ARCH_MAP_CACHED_RO:
+               case MAP_RO:
                        return PTE_FLAGS_CACHED_RO_V7;
                case MAP_CACHED:
                        return PTE_FLAGS_CACHED_V7;
@@ -320,7 +320,7 @@ static uint32_t get_pte_flags(maptype_t map_type)
                }
        } else {
                switch (map_type & MAP_TYPE_MASK) {
-               case ARCH_MAP_CACHED_RO:
+               case MAP_RO:
                case MAP_CODE:
                        return PTE_FLAGS_CACHED_RO_V4;
                case ARCH_MAP_CACHED_RWX:
diff --git a/arch/arm/cpu/mmu_64.c b/arch/arm/cpu/mmu_64.c
index 56c6a21f2b2a..006b2b29478f 100644
--- a/arch/arm/cpu/mmu_64.c
+++ b/arch/arm/cpu/mmu_64.c
@@ -159,7 +159,7 @@ static unsigned long get_pte_attrs(maptype_t map_type)
                return attrs_xn() | MEM_ALLOC_WRITECOMBINE;
        case MAP_CODE:
                return CACHED_MEM | PTE_BLOCK_RO;
-       case ARCH_MAP_CACHED_RO:
+       case MAP_RO:
                return attrs_xn() | CACHED_MEM | PTE_BLOCK_RO;
        case ARCH_MAP_CACHED_RWX:
                return CACHED_MEM;
diff --git a/include/mmu.h b/include/mmu.h
index f79619808829..7d87885a5cb4 100644
--- a/include/mmu.h
+++ b/include/mmu.h
@@ -16,6 +16,12 @@
 #define MAP_WRITECOMBINE       MAP_UNCACHED
 #endif
 
+#ifdef CONFIG_ARCH_HAS_RO_MAPPINGS
+#define MAP_RO                 5
+#else
+#define MAP_RO                 MAP_CACHED
+#endif
+
 #define MAP_TYPE_MASK  0xFFFF
 #define MAP_ARCH(x)    ((u16)~(x))
 
-- 
2.47.3


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