diff options
| author | Charlie Jenkins <charlie@rivosinc.com> | 2023-08-10 02:22:01 +0300 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2023-08-24 00:54:12 +0300 |
| commit | add2cc6b6515f78d3a150f1fbbaf12c28c4bb20a (patch) | |
| tree | 0da0e3e7527e101585eda5a6e9beec4503e8fd0b /arch/riscv/include/asm/processor.h | |
| parent | 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5 (diff) | |
| download | linux-add2cc6b6515f78d3a150f1fbbaf12c28c4bb20a.tar.xz | |
RISC-V: mm: Restrict address space for sv39,sv48,sv57
Make sv48 the default address space for mmap as some applications
currently depend on this assumption. A hint address passed to mmap will
cause the largest address space that fits entirely into the hint to be
used. If the hint is less than or equal to 1<<38, an sv39 address will
be used. An exception is that if the hint address is 0, then a sv48
address will be used. After an address space is completely full, the next
smallest address space will be used.
Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
Link: https://lore.kernel.org/r/20230809232218.849726-2-charlie@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/include/asm/processor.h')
| -rw-r--r-- | arch/riscv/include/asm/processor.h | 52 |
1 files changed, 46 insertions, 6 deletions
diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h index c950a8d9edef..3e23e1786d05 100644 --- a/arch/riscv/include/asm/processor.h +++ b/arch/riscv/include/asm/processor.h @@ -13,19 +13,59 @@ #include <asm/ptrace.h> +#ifdef CONFIG_64BIT +#define DEFAULT_MAP_WINDOW (UL(1) << (MMAP_VA_BITS - 1)) +#define STACK_TOP_MAX TASK_SIZE_64 + +#define arch_get_mmap_end(addr, len, flags) \ +({ \ + unsigned long mmap_end; \ + typeof(addr) _addr = (addr); \ + if ((_addr) == 0 || (IS_ENABLED(CONFIG_COMPAT) && is_compat_task())) \ + mmap_end = STACK_TOP_MAX; \ + else if ((_addr) >= VA_USER_SV57) \ + mmap_end = STACK_TOP_MAX; \ + else if ((((_addr) >= VA_USER_SV48)) && (VA_BITS >= VA_BITS_SV48)) \ + mmap_end = VA_USER_SV48; \ + else \ + mmap_end = VA_USER_SV39; \ + mmap_end; \ +}) + +#define arch_get_mmap_base(addr, base) \ +({ \ + unsigned long mmap_base; \ + typeof(addr) _addr = (addr); \ + typeof(base) _base = (base); \ + unsigned long rnd_gap = DEFAULT_MAP_WINDOW - (_base); \ + if ((_addr) == 0 || (IS_ENABLED(CONFIG_COMPAT) && is_compat_task())) \ + mmap_base = (_base); \ + else if (((_addr) >= VA_USER_SV57) && (VA_BITS >= VA_BITS_SV57)) \ + mmap_base = VA_USER_SV57 - rnd_gap; \ + else if ((((_addr) >= VA_USER_SV48)) && (VA_BITS >= VA_BITS_SV48)) \ + mmap_base = VA_USER_SV48 - rnd_gap; \ + else \ + mmap_base = VA_USER_SV39 - rnd_gap; \ + mmap_base; \ +}) + +#else +#define DEFAULT_MAP_WINDOW TASK_SIZE +#define STACK_TOP_MAX TASK_SIZE +#endif +#define STACK_ALIGN 16 + +#define STACK_TOP DEFAULT_MAP_WINDOW + /* * This decides where the kernel will search for a free chunk of vm * space during mmap's. */ -#define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3) - -#define STACK_TOP TASK_SIZE #ifdef CONFIG_64BIT -#define STACK_TOP_MAX TASK_SIZE_64 +#define TASK_UNMAPPED_BASE PAGE_ALIGN((UL(1) << MMAP_MIN_VA_BITS) / 3) #else -#define STACK_TOP_MAX TASK_SIZE +#define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3) #endif -#define STACK_ALIGN 16 #ifndef __ASSEMBLY__ |