/* SPDX-License-Identifier: GPL-2.0 */ #ifndef __ALPHA_UACCESS_H #define __ALPHA_UACCESS_H #include <asm-generic/access_ok.h> /* * These are the main single-value transfer routines. They automatically * use the right size if we just have the right pointer type. * * As the alpha uses the same address space for kernel and user * data, we can just do these as direct assignments. (Of course, the * exception handling means that it's no longer "just"...) * * Careful to not * (a) re-use the arguments for side effects (sizeof/typeof is ok) * (b) require any knowledge of processes at this stage */ #define put_user(x, ptr) \ __put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) #define get_user(x, ptr) \ __get_user_check((x), (ptr), sizeof(*(ptr))) /* * The "__xxx" versions do not do address space checking, useful when * doing multiple accesses to the same area (the programmer has to do the * checks by hand with "access_ok()") */ #define __put_user(x, ptr) \ __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr))) #define __get_user(x, ptr) \ __get_user_nocheck((x), (ptr), sizeof(*(ptr))) /* * The "lda %1, 2b-1b(%0)" bits are magic to get the assembler to * encode the bits we need for resolving the exception. See the * more extensive comments with fixup_inline_exception below for * more information. */ #define EXC(label,cont,res,err) \ ".section __ex_table,\"a\"\n" \ " .long "#label"-.\n" \ " lda "#res","#cont"-"#label"("#err")\n" \ ".previous\n" extern void __get_user_unknown(void); #define __get_user_nocheck(x, ptr, size) \ ({ \ long __gu_err = 0; \ unsigned long __gu_val; \ __chk_user_ptr(ptr); \ switch (size) { \ case 1: __get_user_8(ptr); break; \ case 2: __get_user_16(ptr); break; \ case 4: __get_user_32(ptr); break; \ case 8: __get_user_64(ptr); break; \ default: __get_user_unknown(); break; \ } \ (x) = (__force __typeof__(*(ptr))) __gu_val; \ __gu_err; \ }) #define __get_user_check(x, ptr, size) \ ({ \ long __gu_err = -EFAULT; \ unsigned long __gu_val = 0; \ const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \ if (__access_ok(__gu_addr, size)) { \ __gu_err = 0; \ switch (size) { \ case 1: __get_user_8(__gu_addr); break; \ case 2: __get_user_16(__gu_addr); break; \ case 4: __get_user_32(__gu_addr); break; \ case 8: __get_user_64(__gu_addr); break; \ default: __get_user_unknown(); break; \ } \ } \ (x) = (__force __typeof__(*(ptr))) __gu_val; \ __gu_err; \ }) struct __large_struct { unsigned long buf[100]; }; #define __m(x) (*(struct __large_struct __user *)(x)) #define __get_user_64(addr) \ __asm__("1: ldq %0,%2\n" \ "2:\n" \ EXC(1b,2b,%0,%1) \ : "=r"(__gu_val), "=r"(__gu_err) \ : "m"(__m(addr)), "1"(__gu_err)) #define __get_user_32(addr) \ __asm__("1: ldl %0,%2\n" \ "2:\n" \ EXC(1b,2b,%0,%1) \ : "=r"(__gu_val), "=r"(__gu_err) \ : "m"(__m(addr)), "1"(__gu_err)) #ifdef __alpha_bwx__ /* Those lucky bastards with ev56 and later CPUs can do byte/word moves. */ #define __get_user_16(addr) \ __asm__("1: ldwu %0,%2\n" \ "2:\n" \ EXC(1b,2b,%0,%1) \ : "=r"(__gu_val), "=r"(__gu_err) \ : "m"(__m(addr)), "1"(__gu_err)) #define __get_user_8(addr) \ __asm__("1: ldbu %0,%2\n" \ "2:\n" \ EXC(1b,2b,%0,%1) \ : "=r"(__gu_val), "=r"(__gu_err) \ : "m"(__m(addr)), "1"(__gu_err)) #else /* Unfortunately, we can't get an unaligned access trap for the sub-word load, so we have to do a general unaligned operation. */ #define __get_user_16(addr) \ { \ long __gu_tmp; \ __asm__("1: ldq_u %0,0(%3)\n" \ "2: ldq_u %1,1(%3)\n" \ " extwl %0,%3,%0\n" \ " extwh %1,%3,%1\n" \ " or %0,%1,%0\n" \ "3:\n" \ EXC(1b,3b,%0,%2) \ EXC(2b,3b,%0,%2) \ : "=&r"(__gu_val), "=&r"(__gu_tmp), "=r"(__gu_err) \ : "r"(addr), "2"(__gu_err)); \ } #define __get_user_8(addr) \ __asm__("1: ldq_u %0,0(%2)\n" \ " extbl %0,%2,%0\n" \ "2:\n" \ EXC(1b,2b,%0,%1) \ : "=&r"(__gu_val), "=r"(__gu_err) \ : "r"(addr), "1"(__gu_err)) #endif extern void __put_user_unknown(void); #define __put_user_nocheck(x, ptr, size) \ ({ \ long __pu_err = 0; \ __chk_user_ptr(ptr); \ switch (size) { \ case 1: __put_user_8(x, ptr); break; \ case 2: __put_user_16(x, ptr); break; \ case 4: __put_user_32(x, ptr); break; \ case 8: __put_user_64(x, ptr); break; \ default: __put_user_unknown(); break; \ } \ __pu_err; \ }) #define __put_user_check(x, ptr, size) \ ({ \ long __pu_err = -EFAULT; \ __typeof__(*(ptr)) __user *__pu_addr = (ptr); \ if (__access_ok(__pu_addr, size)) { \ __pu_err = 0; \ switch (size) { \ case 1: __put_user_8(x, __pu_addr); break; \ case 2: __put_user_16(x, __pu_addr); break; \ case 4: __put_user_32(x, __pu_addr); break; \ case 8: __put_user_64(x, __pu_addr); break; \ default: __put_user_unknown(); break; \ } \ } \ __pu_err; \ }) /* * The "__put_user_xx()" 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 */ #define __put_user_64(x, addr) \ __asm__ __volatile__("1: stq %r2,%1\n" \ "2:\n" \ EXC(1b,2b,$31,%0) \ : "=r"(__pu_err) \ : "m" (__m(addr)), "rJ" (x), "0"(__pu_err)) #define __put_user_32(x, addr) \ __asm__ __volatile__("1: stl %r2,%1\n" \ "2:\n" \ EXC(1b,2b,$31,%0) \ : "=r"(__pu_err) \ : "m"(__m(addr)), "rJ"(x), "0"(__pu_err)) #ifdef __alpha_bwx__ /* Those lucky bastards with ev56 and later CPUs can do byte/word moves. */ #define __put_user_16(x, addr) \ __asm__ __volatile__("1: stw %r2,%1\n" \ "2:\n" \ EXC(1b,2b,$31,%0) \ : "=r"(__pu_err) \ : "m"(__m(addr)), "rJ"(x), "0"(__pu_err)) #define __put_user_8(x, addr) \ __asm__ __volatile__("1: stb %r2,%1\n" \ "2:\n" \ EXC(1b,2b,$31,%0) \ : "=r"(__pu_err) \ : "m"(__m(addr)), "rJ"(x), "0"(__pu_err)) #else /* Unfortunately, we can't get an unaligned access trap for the sub-word write, so we have to do a general unaligned operation. */ #define __put_user_16(x, addr) \ { \ long __pu_tmp1, __pu_tmp2, __pu_tmp3, __pu_tmp4; \ __asm__ __volatile__( \ "1: ldq_u %2,1(%5)\n" \ "2: ldq_u %1,0(%5)\n" \ " inswh %6,%5,%4\n" \ " inswl %6,%5,%3\n" \ " mskwh %2,%5,%2\n" \ " mskwl %1,%5,%1\n" \ " or %2,%4,%2\n" \ " or %1,%3,%1\n" \ "3: stq_u %2,1(%5)\n" \ "4: stq_u %1,0(%5)\n" \ "5:\n" \ EXC(1b,5b,$31,%0) \ EXC(2b,5b,$31,%0) \ EXC(3b,5b,$31,%0) \ EXC(4b,5b,$31,%0) \ : "=r"(__pu_err), "=&r"(__pu_tmp1), \ "=&r"(__pu_tmp2), "=&r"(__pu_tmp3), \ "=&r"(__pu_tmp4) \ : "r"(addr), "r"((unsigned long)(x)), "0"(__pu_err)); \ } #define __put_user_8(x, addr) \ { \ long __pu_tmp1, __pu_tmp2; \ __asm__ __volatile__( \ "1: ldq_u %1,0(%4)\n" \ " insbl %3,%4,%2\n" \ " mskbl %1,%4,%1\n" \ " or %1,%2,%1\n" \ "2: stq_u %1,0(%4)\n" \ "3:\n" \ EXC(1b,3b,$31,%0) \ EXC(2b,3b,$31,%0) \ : "=r"(__pu_err), \ "=&r"(__pu_tmp1), "=&r"(__pu_tmp2) \ : "r"((unsigned long)(x)), "r"(addr), "0"(__pu_err)); \ } #endif /* * Complex access routines */ extern long __copy_user(void *to, const void *from, long len); static inline unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long len) { return __copy_user(to, (__force const void *)from, len); } static inline unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long len) { return __copy_user((__force void *)to, from, len); } extern long __clear_user(void __user *to, long len); static inline long clear_user(void __user *to, long len) { if (__access_ok(to, len)) len = __clear_user(to, len); return len; } extern long strncpy_from_user(char *dest, const char __user *src, long count); extern __must_check long strnlen_user(const char __user *str, long n); #include <asm/extable.h> #endif /* __ALPHA_UACCESS_H */