Gerald Schaefer | 6c2a9e6 | 2006-09-20 15:59:44 +0200 | [diff] [blame^] | 1 | /* |
| 2 | * arch/s390/lib/uaccess_mvcos.c |
| 3 | * |
| 4 | * Optimized user space space access functions based on mvcos. |
| 5 | * |
| 6 | * Copyright (C) IBM Corp. 2006 |
| 7 | * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), |
| 8 | * Gerald Schaefer (gerald.schaefer@de.ibm.com) |
| 9 | */ |
| 10 | |
| 11 | #include <linux/errno.h> |
| 12 | #include <linux/mm.h> |
| 13 | #include <asm/uaccess.h> |
| 14 | #include <asm/futex.h> |
| 15 | |
| 16 | #ifndef __s390x__ |
| 17 | #define AHI "ahi" |
| 18 | #define ALR "alr" |
| 19 | #define CLR "clr" |
| 20 | #define LHI "lhi" |
| 21 | #define SLR "slr" |
| 22 | #else |
| 23 | #define AHI "aghi" |
| 24 | #define ALR "algr" |
| 25 | #define CLR "clgr" |
| 26 | #define LHI "lghi" |
| 27 | #define SLR "slgr" |
| 28 | #endif |
| 29 | |
| 30 | size_t copy_from_user_mvcos(size_t size, const void __user *ptr, void *x) |
| 31 | { |
| 32 | register unsigned long reg0 asm("0") = 0x81UL; |
| 33 | unsigned long tmp1, tmp2; |
| 34 | |
| 35 | tmp1 = -4096UL; |
| 36 | asm volatile( |
| 37 | "0: .insn ss,0xc80000000000,0(%0,%2),0(%1),0\n" |
| 38 | " jz 4f\n" |
| 39 | "1:"ALR" %0,%3\n" |
| 40 | " "SLR" %1,%3\n" |
| 41 | " "SLR" %2,%3\n" |
| 42 | " j 0b\n" |
| 43 | "2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */ |
| 44 | " nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */ |
| 45 | " "SLR" %4,%1\n" |
| 46 | " "CLR" %0,%4\n" /* copy crosses next page boundary? */ |
| 47 | " jnh 5f\n" |
| 48 | "3: .insn ss,0xc80000000000,0(%4,%2),0(%1),0\n" |
| 49 | " "SLR" %0,%4\n" |
| 50 | " j 5f\n" |
| 51 | "4:"SLR" %0,%0\n" |
| 52 | "5: \n" |
| 53 | EX_TABLE(0b,2b) EX_TABLE(3b,5b) |
| 54 | : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2) |
| 55 | : "d" (reg0) : "cc", "memory"); |
| 56 | return size; |
| 57 | } |
| 58 | |
| 59 | size_t copy_to_user_mvcos(size_t size, void __user *ptr, const void *x) |
| 60 | { |
| 61 | register unsigned long reg0 asm("0") = 0x810000UL; |
| 62 | unsigned long tmp1, tmp2; |
| 63 | |
| 64 | tmp1 = -4096UL; |
| 65 | asm volatile( |
| 66 | "0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n" |
| 67 | " jz 4f\n" |
| 68 | "1:"ALR" %0,%3\n" |
| 69 | " "SLR" %1,%3\n" |
| 70 | " "SLR" %2,%3\n" |
| 71 | " j 0b\n" |
| 72 | "2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */ |
| 73 | " nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */ |
| 74 | " "SLR" %4,%1\n" |
| 75 | " "CLR" %0,%4\n" /* copy crosses next page boundary? */ |
| 76 | " jnh 5f\n" |
| 77 | "3: .insn ss,0xc80000000000,0(%4,%1),0(%2),0\n" |
| 78 | " "SLR" %0,%4\n" |
| 79 | " j 5f\n" |
| 80 | "4:"SLR" %0,%0\n" |
| 81 | "5: \n" |
| 82 | EX_TABLE(0b,2b) EX_TABLE(3b,5b) |
| 83 | : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2) |
| 84 | : "d" (reg0) : "cc", "memory"); |
| 85 | return size; |
| 86 | } |
| 87 | |
| 88 | size_t copy_in_user_mvcos(size_t size, void __user *to, const void __user *from) |
| 89 | { |
| 90 | register unsigned long reg0 asm("0") = 0x810081UL; |
| 91 | unsigned long tmp1, tmp2; |
| 92 | |
| 93 | tmp1 = -4096UL; |
| 94 | /* FIXME: copy with reduced length. */ |
| 95 | asm volatile( |
| 96 | "0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n" |
| 97 | " jz 2f\n" |
| 98 | "1:"ALR" %0,%3\n" |
| 99 | " "SLR" %1,%3\n" |
| 100 | " "SLR" %2,%3\n" |
| 101 | " j 0b\n" |
| 102 | "2:"SLR" %0,%0\n" |
| 103 | "3: \n" |
| 104 | EX_TABLE(0b,3b) |
| 105 | : "+a" (size), "+a" (to), "+a" (from), "+a" (tmp1), "=a" (tmp2) |
| 106 | : "d" (reg0) : "cc", "memory"); |
| 107 | return size; |
| 108 | } |
| 109 | |
| 110 | size_t clear_user_mvcos(size_t size, void __user *to) |
| 111 | { |
| 112 | register unsigned long reg0 asm("0") = 0x810000UL; |
| 113 | unsigned long tmp1, tmp2; |
| 114 | |
| 115 | tmp1 = -4096UL; |
| 116 | asm volatile( |
| 117 | "0: .insn ss,0xc80000000000,0(%0,%1),0(%4),0\n" |
| 118 | " jz 4f\n" |
| 119 | "1:"ALR" %0,%2\n" |
| 120 | " "SLR" %1,%2\n" |
| 121 | " j 0b\n" |
| 122 | "2: la %3,4095(%1)\n"/* %4 = to + 4095 */ |
| 123 | " nr %3,%2\n" /* %4 = (to + 4095) & -4096 */ |
| 124 | " "SLR" %3,%1\n" |
| 125 | " "CLR" %0,%3\n" /* copy crosses next page boundary? */ |
| 126 | " jnh 5f\n" |
| 127 | "3: .insn ss,0xc80000000000,0(%3,%1),0(%4),0\n" |
| 128 | " "SLR" %0,%3\n" |
| 129 | " j 5f\n" |
| 130 | "4:"SLR" %0,%0\n" |
| 131 | "5: \n" |
| 132 | EX_TABLE(0b,2b) EX_TABLE(3b,5b) |
| 133 | : "+a" (size), "+a" (to), "+a" (tmp1), "=a" (tmp2) |
| 134 | : "a" (empty_zero_page), "d" (reg0) : "cc", "memory"); |
| 135 | return size; |
| 136 | } |
| 137 | |
| 138 | extern size_t copy_from_user_std_small(size_t, const void __user *, void *); |
| 139 | extern size_t copy_to_user_std_small(size_t, void __user *, const void *); |
| 140 | extern size_t strnlen_user_std(size_t, const char __user *); |
| 141 | extern size_t strncpy_from_user_std(size_t, const char __user *, char *); |
| 142 | extern int futex_atomic_op(int, int __user *, int, int *); |
| 143 | extern int futex_atomic_cmpxchg(int __user *, int, int); |
| 144 | |
| 145 | struct uaccess_ops uaccess_mvcos = { |
| 146 | .copy_from_user = copy_from_user_mvcos, |
| 147 | .copy_from_user_small = copy_from_user_std_small, |
| 148 | .copy_to_user = copy_to_user_mvcos, |
| 149 | .copy_to_user_small = copy_to_user_std_small, |
| 150 | .copy_in_user = copy_in_user_mvcos, |
| 151 | .clear_user = clear_user_mvcos, |
| 152 | .strnlen_user = strnlen_user_std, |
| 153 | .strncpy_from_user = strncpy_from_user_std, |
| 154 | .futex_atomic_op = futex_atomic_op, |
| 155 | .futex_atomic_cmpxchg = futex_atomic_cmpxchg, |
| 156 | }; |