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Diffstat (limited to 'arch/parisc/include/asm/uaccess.h')
| -rw-r--r-- | arch/parisc/include/asm/uaccess.h | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/arch/parisc/include/asm/uaccess.h b/arch/parisc/include/asm/uaccess.h new file mode 100644 index 0000000000..4165079898 --- /dev/null +++ b/arch/parisc/include/asm/uaccess.h @@ -0,0 +1,222 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __PARISC_UACCESS_H +#define __PARISC_UACCESS_H + +/* + * User space memory access functions + */ +#include <asm/page.h> +#include <asm/cache.h> + +#include <linux/bug.h> +#include <linux/string.h> + +#define TASK_SIZE_MAX DEFAULT_TASK_SIZE +#include <asm/pgtable.h> +#include <asm-generic/access_ok.h> + +#define put_user __put_user +#define get_user __get_user + +#if !defined(CONFIG_64BIT) +#define LDD_USER(sr, val, ptr) __get_user_asm64(sr, val, ptr) +#define STD_USER(sr, x, ptr) __put_user_asm64(sr, x, ptr) +#else +#define LDD_USER(sr, val, ptr) __get_user_asm(sr, val, "ldd", ptr) +#define STD_USER(sr, x, ptr) __put_user_asm(sr, "std", x, ptr) +#endif + +/* + * The exception table contains two values: the first is the relative offset to + * the address of the instruction that is allowed to fault, and the second is + * the relative offset to the address of the fixup routine. Since relative + * addresses are used, 32bit values are sufficient even on 64bit kernel. + */ + +#define ARCH_HAS_RELATIVE_EXTABLE +struct exception_table_entry { + int insn; /* relative address of insn that is allowed to fault. */ + int fixup; /* relative address of fixup routine */ +}; + +#define ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr )\ + ".section __ex_table,\"aw\"\n" \ + ".align 4\n" \ + ".word (" #fault_addr " - .), (" #except_addr " - .)\n\t" \ + ".previous\n" + +/* + * ASM_EXCEPTIONTABLE_ENTRY_EFAULT() creates a special exception table entry + * (with lowest bit set) for which the fault handler in fixup_exception() will + * load -EFAULT into %r29 for a read or write fault, and zeroes the target + * register in case of a read fault in get_user(). + */ +#define ASM_EXCEPTIONTABLE_REG 29 +#define ASM_EXCEPTIONTABLE_VAR(__variable) \ + register long __variable __asm__ ("r29") = 0 +#define ASM_EXCEPTIONTABLE_ENTRY_EFAULT( fault_addr, except_addr )\ + ASM_EXCEPTIONTABLE_ENTRY( fault_addr, except_addr + 1) + +#define __get_user_internal(sr, val, ptr) \ +({ \ + ASM_EXCEPTIONTABLE_VAR(__gu_err); \ + \ + switch (sizeof(*(ptr))) { \ + case 1: __get_user_asm(sr, val, "ldb", ptr); break; \ + case 2: __get_user_asm(sr, val, "ldh", ptr); break; \ + case 4: __get_user_asm(sr, val, "ldw", ptr); break; \ + case 8: LDD_USER(sr, val, ptr); break; \ + default: BUILD_BUG(); \ + } \ + \ + __gu_err; \ +}) + +#define __get_user(val, ptr) \ +({ \ + __get_user_internal(SR_USER, val, ptr); \ +}) + +#define __get_user_asm(sr, val, ldx, ptr) \ +{ \ + register long __gu_val; \ + \ + __asm__("1: " ldx " 0(%%sr%2,%3),%0\n" \ + "9:\n" \ + ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ + : "=r"(__gu_val), "+r"(__gu_err) \ + : "i"(sr), "r"(ptr)); \ + \ + (val) = (__force __typeof__(*(ptr))) __gu_val; \ +} + +#define __get_kernel_nofault(dst, src, type, err_label) \ +{ \ + type __z; \ + long __err; \ + __err = __get_user_internal(SR_KERNEL, __z, (type *)(src)); \ + if (unlikely(__err)) \ + goto err_label; \ + else \ + *(type *)(dst) = __z; \ +} + + +#if !defined(CONFIG_64BIT) + +#define __get_user_asm64(sr, val, ptr) \ +{ \ + union { \ + unsigned long long l; \ + __typeof__(*(ptr)) t; \ + } __gu_tmp; \ + \ + __asm__(" copy %%r0,%R0\n" \ + "1: ldw 0(%%sr%2,%3),%0\n" \ + "2: ldw 4(%%sr%2,%3),%R0\n" \ + "9:\n" \ + ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ + ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \ + : "=&r"(__gu_tmp.l), "+r"(__gu_err) \ + : "i"(sr), "r"(ptr)); \ + \ + (val) = __gu_tmp.t; \ +} + +#endif /* !defined(CONFIG_64BIT) */ + + +#define __put_user_internal(sr, x, ptr) \ +({ \ + ASM_EXCEPTIONTABLE_VAR(__pu_err); \ + \ + switch (sizeof(*(ptr))) { \ + case 1: __put_user_asm(sr, "stb", x, ptr); break; \ + case 2: __put_user_asm(sr, "sth", x, ptr); break; \ + case 4: __put_user_asm(sr, "stw", x, ptr); break; \ + case 8: STD_USER(sr, x, ptr); break; \ + default: BUILD_BUG(); \ + } \ + \ + __pu_err; \ +}) + +#define __put_user(x, ptr) \ +({ \ + __typeof__(&*(ptr)) __ptr = ptr; \ + __typeof__(*(__ptr)) __x = (__typeof__(*(__ptr)))(x); \ + __put_user_internal(SR_USER, __x, __ptr); \ +}) + +#define __put_kernel_nofault(dst, src, type, err_label) \ +{ \ + type __z = *(type *)(src); \ + long __err; \ + __err = __put_user_internal(SR_KERNEL, __z, (type *)(dst)); \ + if (unlikely(__err)) \ + goto err_label; \ +} + + + + +/* + * 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 fixups are executed in the context of the fault, + * and any registers used there must be listed as clobbers. + * The register holding the possible EFAULT error (ASM_EXCEPTIONTABLE_REG) + * is already listed as input and output register. + */ + +#define __put_user_asm(sr, stx, x, ptr) \ + __asm__ __volatile__ ( \ + "1: " stx " %1,0(%%sr%2,%3)\n" \ + "9:\n" \ + ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ + : "+r"(__pu_err) \ + : "r"(x), "i"(sr), "r"(ptr)) + + +#if !defined(CONFIG_64BIT) + +#define __put_user_asm64(sr, __val, ptr) do { \ + __asm__ __volatile__ ( \ + "1: stw %1,0(%%sr%2,%3)\n" \ + "2: stw %R1,4(%%sr%2,%3)\n" \ + "9:\n" \ + ASM_EXCEPTIONTABLE_ENTRY_EFAULT(1b, 9b) \ + ASM_EXCEPTIONTABLE_ENTRY_EFAULT(2b, 9b) \ + : "+r"(__pu_err) \ + : "r"(__val), "i"(sr), "r"(ptr)); \ +} while (0) + +#endif /* !defined(CONFIG_64BIT) */ + + +/* + * Complex access routines -- external declarations + */ + +extern long strncpy_from_user(char *, const char __user *, long); +extern __must_check unsigned lclear_user(void __user *, unsigned long); +extern __must_check long strnlen_user(const char __user *src, long n); +/* + * Complex access routines -- macros + */ + +#define clear_user lclear_user +#define __clear_user lclear_user + +unsigned long __must_check raw_copy_to_user(void __user *dst, const void *src, + unsigned long len); +unsigned long __must_check raw_copy_from_user(void *dst, const void __user *src, + unsigned long len); +#define INLINE_COPY_TO_USER +#define INLINE_COPY_FROM_USER + +struct pt_regs; +int fixup_exception(struct pt_regs *regs); + +#endif /* __PARISC_UACCESS_H */ |