[PATCH v2 09/28] ARM: mmu: Specify size in bytes in create_sections()
Andrey Smirnov
andrew.smirnov at gmail.com
Wed May 16 13:00:17 PDT 2018
Seeing
create_sections(ttb, 0, PAGE_SIZE, ...);
as the code the creates initial flat 4 GiB mapping is a bit less
intuitive then
create_sections(ttb, 0, SZ_4G, ...);
so, for the sake of clarification, convert create_sections() to accept
size in bytes and do bytes -> MiB converstion as a part of the
function.
NOTE: To keep all of the arguments of create_sections() 32-bit:
- Move all of the real code into a helper function accepting first
and last addresses of the region (e.g passing 0 and U32_MAX
means all 4GiB of address space)
- Convert create_section() into a macro that does necessary size
-> last addres conversion under the hood to preserve original API
Signed-off-by: Andrey Smirnov <andrew.smirnov at gmail.com>
---
arch/arm/cpu/mmu-early.c | 4 ++--
arch/arm/cpu/mmu.c | 4 ++--
arch/arm/cpu/mmu.h | 22 ++++++++++++++++------
3 files changed, 20 insertions(+), 10 deletions(-)
diff --git a/arch/arm/cpu/mmu-early.c b/arch/arm/cpu/mmu-early.c
index 70ece0d2f..136b33c3a 100644
--- a/arch/arm/cpu/mmu-early.c
+++ b/arch/arm/cpu/mmu-early.c
@@ -16,7 +16,7 @@ static void map_cachable(unsigned long start, unsigned long size)
start = ALIGN_DOWN(start, SZ_1M);
size = ALIGN(size, SZ_1M);
- create_sections(ttb, start, size >> 20, PMD_SECT_AP_WRITE |
+ create_sections(ttb, start, size, PMD_SECT_AP_WRITE |
PMD_SECT_AP_READ | PMD_TYPE_SECT | PMD_SECT_WB);
}
@@ -30,7 +30,7 @@ void mmu_early_enable(unsigned long membase, unsigned long memsize,
set_ttbr(ttb);
set_domain(DOMAIN_MANAGER);
- create_sections(ttb, 0, 4096, PMD_SECT_AP_WRITE |
+ create_sections(ttb, 0, SZ_4G, PMD_SECT_AP_WRITE |
PMD_SECT_AP_READ | PMD_TYPE_SECT);
map_cachable(membase, memsize);
diff --git a/arch/arm/cpu/mmu.c b/arch/arm/cpu/mmu.c
index 0c367e47c..f02c99f65 100644
--- a/arch/arm/cpu/mmu.c
+++ b/arch/arm/cpu/mmu.c
@@ -460,7 +460,7 @@ static int mmu_init(void)
set_domain(DOMAIN_MANAGER);
/* create a flat mapping using 1MiB sections */
- create_sections(ttb, 0, PAGE_SIZE, PMD_SECT_AP_WRITE | PMD_SECT_AP_READ |
+ create_sections(ttb, 0, SZ_4G, PMD_SECT_AP_WRITE | PMD_SECT_AP_READ |
PMD_TYPE_SECT);
__mmu_cache_flush();
@@ -472,7 +472,7 @@ static int mmu_init(void)
* below
*/
for_each_memory_bank(bank) {
- create_sections(ttb, bank->start, bank->size >> 20,
+ create_sections(ttb, bank->start, bank->size,
PMD_SECT_DEF_CACHED);
__mmu_cache_flush();
}
diff --git a/arch/arm/cpu/mmu.h b/arch/arm/cpu/mmu.h
index d71cd7e38..52689359a 100644
--- a/arch/arm/cpu/mmu.h
+++ b/arch/arm/cpu/mmu.h
@@ -27,16 +27,26 @@ static inline void set_domain(unsigned val)
}
static inline void
-create_sections(uint32_t *ttb, unsigned long addr,
- int size_m, unsigned int flags)
+__create_sections(uint32_t *ttb, unsigned long first,
+ unsigned long last, unsigned int flags)
{
- unsigned long ttb_start = addr >> 20;
- unsigned long ttb_end = ttb_start + size_m;
- unsigned int i;
+ unsigned long ttb_start = first >> 20;
+ unsigned long ttb_end = (last >> 20) + 1;
+ unsigned int i, addr;
- for (i = ttb_start; i < ttb_end; i++, addr += SZ_1M)
+ for (i = ttb_start, addr = first; i < ttb_end; i++, addr += SZ_1M)
ttb[i] = addr | flags;
}
+#define create_sections(ttb, addr, size, flags) \
+ ({ \
+ typeof(addr) __addr = addr; \
+ typeof(size) __size = size; \
+ /* Check for overflow */ \
+ BUG_ON(__addr > ULONG_MAX - __size + 1); \
+ __create_sections(ttb, __addr, __addr + (size) - 1, \
+ flags); \
+ })
+
#endif /* __ARM_MMU_H */
--
2.17.0
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