[PATCH 07/16] powerpc: mm: Support MAP_BELOW_HINT

Charlie Jenkins
2024-08-28T08:00:43Z

Add support for MAP_BELOW_HINT to arch_get_mmap_base() and
arch_get_mmap_end().

Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
---
arch/powerpc/include/asm/task_size_64.h | 36 +++++++++++++++++++++++++++------
1 file changed, 30 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/include/asm/task_size_64.h b/arch/powerpc/include/asm/task_size_64.h
index 239b363841aa..a37a5a81365d 100644
--- a/arch/powerpc/include/asm/task_size_64.h
+++ b/arch/powerpc/include/asm/task_size_64.h
@@ -72,12 +72,36 @@
#define STACK_TOP_MAX TASK_SIZE_USER64
#define STACK_TOP (is_32bit_task() ? STACK_TOP_USER32 : STACK_TOP_USER64)

-#define arch_get_mmap_base(addr, len, base, flags) \
- (((addr) > DEFAULT_MAP_WINDOW) ? (base) + TASK_SIZE - DEFAULT_MAP_WINDOW : (base))
+#define arch_get_mmap_base(addr, len, base, flags) \
+({ \
+ unsigned long mmap_base; \
+ typeof(flags) _flags = (flags); \
+ typeof(addr) _addr = (addr); \
+ typeof(base) _base = (base); \
+ typeof(len) _len = (len); \
+ unsigned long rnd_gap = DEFAULT_MAP_WINDOW - (_base); \
+ if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1)))\
+ mmap_base = (_addr + _len) - rnd_gap; \
+ else \
+ mmap_end = ((_addr > DEFAULT_MAP_WINDOW) ? \
+ _base + TASK_SIZE - DEFAULT_MAP_WINDOW : \
+ _base); \
+ mmap_end; \
+})

-#define arch_get_mmap_end(addr, len, flags) \
- (((addr) > DEFAULT_MAP_WINDOW) || \
- (((flags) & MAP_FIXED) && ((addr) + (len) > DEFAULT_MAP_WINDOW)) ? TASK_SIZE : \
- DEFAULT_MAP_WINDOW)
+#define arch_get_mmap_end(addr, len, flags) \
+({ \
+ unsigned long mmap_end; \
+ typeof(flags) _flags = (flags); \
+ typeof(addr) _addr = (addr); \
+ typeof(len) _len = (len); \
+ if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1))) \
+ mmap_end = (_addr + _len); \
+ else \
+ mmap_end = (((_addr) > DEFAULT_MAP_WINDOW) || \
+ (((_flags) & MAP_FIXED) && ((_addr) + (_len) > DEFAULT_MAP_WINDOW))\
+ ? TASK_SIZE : DEFAULT_MAP_WINDOW) \
+ mmap_end; \
+})

#endif /* _ASM_POWERPC_TASK_SIZE_64_H */

--
2.45.0