diff options
Diffstat (limited to 'arch/arc/include/asm/uaccess.h')
| -rw-r--r-- | arch/arc/include/asm/uaccess.h | 123 |
1 files changed, 8 insertions, 115 deletions
diff --git a/arch/arc/include/asm/uaccess.h b/arch/arc/include/asm/uaccess.h index ea40ec7f6cae..1e8809ea000a 100644 --- a/arch/arc/include/asm/uaccess.h +++ b/arch/arc/include/asm/uaccess.h @@ -23,35 +23,6 @@ #include <linux/string.h> /* for generic string functions */ - -#define __kernel_ok (uaccess_kernel()) - -/* - * Algorithmically, for __user_ok() we want do: - * (start < TASK_SIZE) && (start+len < TASK_SIZE) - * where TASK_SIZE could either be retrieved from thread_info->addr_limit or - * emitted directly in code. - * - * This can however be rewritten as follows: - * (len <= TASK_SIZE) && (start+len < TASK_SIZE) - * - * Because it essentially checks if buffer end is within limit and @len is - * non-ngeative, which implies that buffer start will be within limit too. - * - * The reason for rewriting being, for majority of cases, @len is generally - * compile time constant, causing first sub-expression to be compile time - * subsumed. - * - * The second part would generate weird large LIMMs e.g. (0x6000_0000 - 0x10), - * so we check for TASK_SIZE using get_fs() since the addr_limit load from mem - * would already have been done at this call site for __kernel_ok() - * - */ -#define __user_ok(addr, sz) (((sz) <= TASK_SIZE) && \ - ((addr) <= (get_fs() - (sz)))) -#define __access_ok(addr, sz) (unlikely(__kernel_ok) || \ - likely(__user_ok((addr), (sz)))) - /*********** Single byte/hword/word copies ******************/ #define __get_user_fn(sz, u, k) \ @@ -175,8 +146,9 @@ raw_copy_from_user(void *to, const void __user *from, unsigned long n) if (n == 0) return 0; - /* unaligned */ - if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) { + /* fallback for unaligned access when hardware doesn't support */ + if (!IS_ENABLED(CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS) && + (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3))) { unsigned char tmp; @@ -402,8 +374,9 @@ raw_copy_to_user(void __user *to, const void *from, unsigned long n) if (n == 0) return 0; - /* unaligned */ - if (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3)) { + /* fallback for unaligned access when hardware doesn't support */ + if (!IS_ENABLED(CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS) && + (((unsigned long)to & 0x3) || ((unsigned long)from & 0x3))) { unsigned char tmp; @@ -613,7 +586,7 @@ raw_copy_to_user(void __user *to, const void *from, unsigned long n) return res; } -static inline unsigned long __arc_clear_user(void __user *to, unsigned long n) +static inline unsigned long __clear_user(void __user *to, unsigned long n) { long res = n; unsigned char *d_char = to; @@ -655,91 +628,11 @@ static inline unsigned long __arc_clear_user(void __user *to, unsigned long n) return res; } -static inline long -__arc_strncpy_from_user(char *dst, const char __user *src, long count) -{ - long res = 0; - char val; - - if (count == 0) - return 0; - - __asm__ __volatile__( - " mov lp_count, %5 \n" - " lp 3f \n" - "1: ldb.ab %3, [%2, 1] \n" - " breq.d %3, 0, 3f \n" - " stb.ab %3, [%1, 1] \n" - " add %0, %0, 1 # Num of NON NULL bytes copied \n" - "3: \n" - " .section .fixup, \"ax\" \n" - " .align 4 \n" - "4: mov %0, %4 # sets @res as -EFAULT \n" - " j 3b \n" - " .previous \n" - " .section __ex_table, \"a\" \n" - " .align 4 \n" - " .word 1b, 4b \n" - " .previous \n" - : "+r"(res), "+r"(dst), "+r"(src), "=r"(val) - : "g"(-EFAULT), "r"(count) - : "lp_count", "memory"); - - return res; -} - -static inline long __arc_strnlen_user(const char __user *s, long n) -{ - long res, tmp1, cnt; - char val; - - __asm__ __volatile__( - " mov %2, %1 \n" - "1: ldb.ab %3, [%0, 1] \n" - " breq.d %3, 0, 2f \n" - " sub.f %2, %2, 1 \n" - " bnz 1b \n" - " sub %2, %2, 1 \n" - "2: sub %0, %1, %2 \n" - "3: ;nop \n" - " .section .fixup, \"ax\" \n" - " .align 4 \n" - "4: mov %0, 0 \n" - " j 3b \n" - " .previous \n" - " .section __ex_table, \"a\" \n" - " .align 4 \n" - " .word 1b, 4b \n" - " .previous \n" - : "=r"(res), "=r"(tmp1), "=r"(cnt), "=r"(val) - : "0"(s), "1"(n) - : "memory"); - - return res; -} - -#ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE - #define INLINE_COPY_TO_USER #define INLINE_COPY_FROM_USER -#define __clear_user(d, n) __arc_clear_user(d, n) -#define __strncpy_from_user(d, s, n) __arc_strncpy_from_user(d, s, n) -#define __strnlen_user(s, n) __arc_strnlen_user(s, n) -#else -extern unsigned long arc_clear_user_noinline(void __user *to, - unsigned long n); -extern long arc_strncpy_from_user_noinline (char *dst, const char __user *src, - long count); -extern long arc_strnlen_user_noinline(const char __user *src, long n); - -#define __clear_user(d, n) arc_clear_user_noinline(d, n) -#define __strncpy_from_user(d, s, n) arc_strncpy_from_user_noinline(d, s, n) -#define __strnlen_user(s, n) arc_strnlen_user_noinline(s, n) - -#endif +#define __clear_user __clear_user -#include <asm/segment.h> #include <asm-generic/uaccess.h> #endif |