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Diffstat (limited to 'arch/parisc/include/asm/uaccess.h')
| -rw-r--r-- | arch/parisc/include/asm/uaccess.h | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/uaccess.h b/arch/parisc/include/asm/uaccess.h new file mode 100644 index 000000000..0abdd4c60 --- /dev/null +++ b/arch/parisc/include/asm/uaccess.h @@ -0,0 +1,260 @@ +#ifndef __PARISC_UACCESS_H +#define __PARISC_UACCESS_H + +/* + * User space memory access functions + */ +#include <asm/page.h> +#include <asm/cache.h> +#include <asm/errno.h> +#include <asm-generic/uaccess-unaligned.h> + +#include <linux/bug.h> + +#define VERIFY_READ 0 +#define VERIFY_WRITE 1 + +#define KERNEL_DS ((mm_segment_t){0}) +#define USER_DS ((mm_segment_t){1}) + +#define segment_eq(a, b) ((a).seg == (b).seg) + +#define get_ds() (KERNEL_DS) +#define get_fs() (current_thread_info()->addr_limit) +#define set_fs(x) (current_thread_info()->addr_limit = (x)) + +/* + * Note that since kernel addresses are in a separate address space on + * parisc, we don't need to do anything for access_ok(). + * We just let the page fault handler do the right thing. This also means + * that put_user is the same as __put_user, etc. + */ + +static inline long access_ok(int type, const void __user * addr, + unsigned long size) +{ + return 1; +} + +#define put_user __put_user +#define get_user __get_user + +#if !defined(CONFIG_64BIT) +#define LDD_KERNEL(ptr) BUILD_BUG() +#define LDD_USER(ptr) BUILD_BUG() +#define STD_KERNEL(x, ptr) __put_kernel_asm64(x, ptr) +#define STD_USER(x, ptr) __put_user_asm64(x, ptr) +#define ASM_WORD_INSN ".word\t" +#else +#define LDD_KERNEL(ptr) __get_kernel_asm("ldd", ptr) +#define LDD_USER(ptr) __get_user_asm("ldd", ptr) +#define STD_KERNEL(x, ptr) __put_kernel_asm("std", x, ptr) +#define STD_USER(x, ptr) __put_user_asm("std", x, ptr) +#define ASM_WORD_INSN ".dword\t" +#endif + +/* + * The exception table contains two values: the first is an address + * for an instruction that is allowed to fault, and the second is + * the address to the fixup routine. Even on a 64bit kernel we could + * use a 32bit (unsigned int) address here. + */ + +struct exception_table_entry { + unsigned long insn; /* address of insn that is allowed to fault. */ + unsigned long fixup; /* fixup routine */ +}; + +#define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\ + ".section __ex_table,\"aw\"\n" \ + ASM_WORD_INSN #fault_addr ", " #except_addr "\n\t" \ + ".previous\n" + +/* + * The page fault handler stores, in a per-cpu area, the following information + * if a fixup routine is available. + */ +struct exception_data { + unsigned long fault_ip; + unsigned long fault_space; + unsigned long fault_addr; +}; + +#define __get_user(x, ptr) \ +({ \ + register long __gu_err __asm__ ("r8") = 0; \ + register long __gu_val __asm__ ("r9") = 0; \ + \ + if (segment_eq(get_fs(), KERNEL_DS)) { \ + switch (sizeof(*(ptr))) { \ + case 1: __get_kernel_asm("ldb", ptr); break; \ + case 2: __get_kernel_asm("ldh", ptr); break; \ + case 4: __get_kernel_asm("ldw", ptr); break; \ + case 8: LDD_KERNEL(ptr); break; \ + default: BUILD_BUG(); break; \ + } \ + } \ + else { \ + switch (sizeof(*(ptr))) { \ + case 1: __get_user_asm("ldb", ptr); break; \ + case 2: __get_user_asm("ldh", ptr); break; \ + case 4: __get_user_asm("ldw", ptr); break; \ + case 8: LDD_USER(ptr); break; \ + default: BUILD_BUG(); break; \ + } \ + } \ + \ + (x) = (__force __typeof__(*(ptr))) __gu_val; \ + __gu_err; \ +}) + +#define __get_kernel_asm(ldx, ptr) \ + __asm__("\n1:\t" ldx "\t0(%2),%0\n\t" \ + ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\ + : "=r"(__gu_val), "=r"(__gu_err) \ + : "r"(ptr), "1"(__gu_err) \ + : "r1"); + +#define __get_user_asm(ldx, ptr) \ + __asm__("\n1:\t" ldx "\t0(%%sr3,%2),%0\n\t" \ + ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_get_user_skip_1)\ + : "=r"(__gu_val), "=r"(__gu_err) \ + : "r"(ptr), "1"(__gu_err) \ + : "r1"); + +#define __put_user(x, ptr) \ +({ \ + register long __pu_err __asm__ ("r8") = 0; \ + __typeof__(*(ptr)) __x = (__typeof__(*(ptr)))(x); \ + \ + if (segment_eq(get_fs(), KERNEL_DS)) { \ + switch (sizeof(*(ptr))) { \ + case 1: __put_kernel_asm("stb", __x, ptr); break; \ + case 2: __put_kernel_asm("sth", __x, ptr); break; \ + case 4: __put_kernel_asm("stw", __x, ptr); break; \ + case 8: STD_KERNEL(__x, ptr); break; \ + default: BUILD_BUG(); break; \ + } \ + } \ + else { \ + switch (sizeof(*(ptr))) { \ + case 1: __put_user_asm("stb", __x, ptr); break; \ + case 2: __put_user_asm("sth", __x, ptr); break; \ + case 4: __put_user_asm("stw", __x, ptr); break; \ + case 8: STD_USER(__x, ptr); break; \ + default: BUILD_BUG(); break; \ + } \ + } \ + \ + __pu_err; \ +}) + +/* + * The "__put_user/kernel_asm()" macros tell gcc they read from memory + * instead of writing. This is because they do not write to any memory + * gcc knows about, so there are no aliasing issues. These macros must + * also be aware that "fixup_put_user_skip_[12]" are executed in the + * context of the fault, and any registers used there must be listed + * as clobbers. In this case only "r1" is used by the current routines. + * r8/r9 are already listed as err/val. + */ + +#define __put_kernel_asm(stx, x, ptr) \ + __asm__ __volatile__ ( \ + "\n1:\t" stx "\t%2,0(%1)\n\t" \ + ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\ + : "=r"(__pu_err) \ + : "r"(ptr), "r"(x), "0"(__pu_err) \ + : "r1") + +#define __put_user_asm(stx, x, ptr) \ + __asm__ __volatile__ ( \ + "\n1:\t" stx "\t%2,0(%%sr3,%1)\n\t" \ + ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_1)\ + : "=r"(__pu_err) \ + : "r"(ptr), "r"(x), "0"(__pu_err) \ + : "r1") + + +#if !defined(CONFIG_64BIT) + +#define __put_kernel_asm64(__val, ptr) do { \ + __asm__ __volatile__ ( \ + "\n1:\tstw %2,0(%1)" \ + "\n2:\tstw %R2,4(%1)\n\t" \ + ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\ + ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\ + : "=r"(__pu_err) \ + : "r"(ptr), "r"(__val), "0"(__pu_err) \ + : "r1"); \ +} while (0) + +#define __put_user_asm64(__val, ptr) do { \ + __asm__ __volatile__ ( \ + "\n1:\tstw %2,0(%%sr3,%1)" \ + "\n2:\tstw %R2,4(%%sr3,%1)\n\t" \ + ASM_EXCEPTIONTABLE_ENTRY(1b, fixup_put_user_skip_2)\ + ASM_EXCEPTIONTABLE_ENTRY(2b, fixup_put_user_skip_1)\ + : "=r"(__pu_err) \ + : "r"(ptr), "r"(__val), "0"(__pu_err) \ + : "r1"); \ +} while (0) + +#endif /* !defined(CONFIG_64BIT) */ + + +/* + * Complex access routines -- external declarations + */ + +extern unsigned long lcopy_to_user(void __user *, const void *, unsigned long); +extern unsigned long lcopy_from_user(void *, const void __user *, unsigned long); +extern unsigned long lcopy_in_user(void __user *, const void __user *, unsigned long); +extern long strncpy_from_user(char *, const char __user *, long); +extern unsigned lclear_user(void __user *, unsigned long); +extern long lstrnlen_user(const char __user *, long); +/* + * Complex access routines -- macros + */ +#define user_addr_max() (~0UL) + +#define strnlen_user lstrnlen_user +#define strlen_user(str) lstrnlen_user(str, 0x7fffffffL) +#define clear_user lclear_user +#define __clear_user lclear_user + +unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len); +#define __copy_to_user copy_to_user +unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len); +unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len); +#define __copy_in_user copy_in_user +#define __copy_to_user_inatomic __copy_to_user +#define __copy_from_user_inatomic __copy_from_user + +extern void copy_from_user_overflow(void) +#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS + __compiletime_error("copy_from_user() buffer size is not provably correct") +#else + __compiletime_warning("copy_from_user() buffer size is not provably correct") +#endif +; + +static inline unsigned long __must_check copy_from_user(void *to, + const void __user *from, + unsigned long n) +{ + int sz = __compiletime_object_size(to); + int ret = -EFAULT; + + if (likely(sz == -1 || !__builtin_constant_p(n) || sz >= n)) + ret = __copy_from_user(to, from, n); + else + copy_from_user_overflow(); + + return ret; +} + +struct pt_regs; +int fixup_exception(struct pt_regs *regs); + +#endif /* __PARISC_UACCESS_H */ |