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 | |
Gerald Schaefer | 59f35d5 | 2006-12-04 15:40:45 +0100 | [diff] [blame] | 30 | extern size_t copy_from_user_std(size_t, const void __user *, void *); |
| 31 | extern size_t copy_to_user_std(size_t, void __user *, const void *); |
| 32 | |
Gerald Schaefer | 6c2a9e6 | 2006-09-20 15:59:44 +0200 | [diff] [blame] | 33 | size_t copy_from_user_mvcos(size_t size, const void __user *ptr, void *x) |
| 34 | { |
| 35 | register unsigned long reg0 asm("0") = 0x81UL; |
| 36 | unsigned long tmp1, tmp2; |
| 37 | |
| 38 | tmp1 = -4096UL; |
| 39 | asm volatile( |
| 40 | "0: .insn ss,0xc80000000000,0(%0,%2),0(%1),0\n" |
Martin Schwidefsky | 52149ba | 2006-09-28 16:56:03 +0200 | [diff] [blame] | 41 | " jz 7f\n" |
Gerald Schaefer | 6c2a9e6 | 2006-09-20 15:59:44 +0200 | [diff] [blame] | 42 | "1:"ALR" %0,%3\n" |
| 43 | " "SLR" %1,%3\n" |
| 44 | " "SLR" %2,%3\n" |
| 45 | " j 0b\n" |
| 46 | "2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */ |
| 47 | " nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */ |
| 48 | " "SLR" %4,%1\n" |
| 49 | " "CLR" %0,%4\n" /* copy crosses next page boundary? */ |
Martin Schwidefsky | 52149ba | 2006-09-28 16:56:03 +0200 | [diff] [blame] | 50 | " jnh 4f\n" |
Gerald Schaefer | 6c2a9e6 | 2006-09-20 15:59:44 +0200 | [diff] [blame] | 51 | "3: .insn ss,0xc80000000000,0(%4,%2),0(%1),0\n" |
| 52 | " "SLR" %0,%4\n" |
Martin Schwidefsky | 52149ba | 2006-09-28 16:56:03 +0200 | [diff] [blame] | 53 | " "ALR" %2,%4\n" |
| 54 | "4:"LHI" %4,-1\n" |
| 55 | " "ALR" %4,%0\n" /* copy remaining size, subtract 1 */ |
| 56 | " bras %3,6f\n" /* memset loop */ |
| 57 | " xc 0(1,%2),0(%2)\n" |
| 58 | "5: xc 0(256,%2),0(%2)\n" |
| 59 | " la %2,256(%2)\n" |
| 60 | "6:"AHI" %4,-256\n" |
| 61 | " jnm 5b\n" |
| 62 | " ex %4,0(%3)\n" |
| 63 | " j 8f\n" |
| 64 | "7:"SLR" %0,%0\n" |
| 65 | "8: \n" |
| 66 | EX_TABLE(0b,2b) EX_TABLE(3b,4b) |
Gerald Schaefer | 6c2a9e6 | 2006-09-20 15:59:44 +0200 | [diff] [blame] | 67 | : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2) |
| 68 | : "d" (reg0) : "cc", "memory"); |
| 69 | return size; |
| 70 | } |
| 71 | |
Gerald Schaefer | 59f35d5 | 2006-12-04 15:40:45 +0100 | [diff] [blame] | 72 | size_t copy_from_user_mvcos_check(size_t size, const void __user *ptr, void *x) |
| 73 | { |
| 74 | if (size <= 256) |
| 75 | return copy_from_user_std(size, ptr, x); |
| 76 | return copy_from_user_mvcos(size, ptr, x); |
| 77 | } |
| 78 | |
Gerald Schaefer | 6c2a9e6 | 2006-09-20 15:59:44 +0200 | [diff] [blame] | 79 | size_t copy_to_user_mvcos(size_t size, void __user *ptr, const void *x) |
| 80 | { |
| 81 | register unsigned long reg0 asm("0") = 0x810000UL; |
| 82 | unsigned long tmp1, tmp2; |
| 83 | |
| 84 | tmp1 = -4096UL; |
| 85 | asm volatile( |
| 86 | "0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n" |
| 87 | " jz 4f\n" |
| 88 | "1:"ALR" %0,%3\n" |
| 89 | " "SLR" %1,%3\n" |
| 90 | " "SLR" %2,%3\n" |
| 91 | " j 0b\n" |
| 92 | "2: la %4,4095(%1)\n"/* %4 = ptr + 4095 */ |
| 93 | " nr %4,%3\n" /* %4 = (ptr + 4095) & -4096 */ |
| 94 | " "SLR" %4,%1\n" |
| 95 | " "CLR" %0,%4\n" /* copy crosses next page boundary? */ |
| 96 | " jnh 5f\n" |
| 97 | "3: .insn ss,0xc80000000000,0(%4,%1),0(%2),0\n" |
| 98 | " "SLR" %0,%4\n" |
| 99 | " j 5f\n" |
| 100 | "4:"SLR" %0,%0\n" |
| 101 | "5: \n" |
| 102 | EX_TABLE(0b,2b) EX_TABLE(3b,5b) |
| 103 | : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2) |
| 104 | : "d" (reg0) : "cc", "memory"); |
| 105 | return size; |
| 106 | } |
| 107 | |
Gerald Schaefer | 59f35d5 | 2006-12-04 15:40:45 +0100 | [diff] [blame] | 108 | size_t copy_to_user_mvcos_check(size_t size, void __user *ptr, const void *x) |
| 109 | { |
| 110 | if (size <= 256) |
| 111 | return copy_to_user_std(size, ptr, x); |
| 112 | return copy_to_user_mvcos(size, ptr, x); |
| 113 | } |
| 114 | |
Gerald Schaefer | 6c2a9e6 | 2006-09-20 15:59:44 +0200 | [diff] [blame] | 115 | size_t copy_in_user_mvcos(size_t size, void __user *to, const void __user *from) |
| 116 | { |
| 117 | register unsigned long reg0 asm("0") = 0x810081UL; |
| 118 | unsigned long tmp1, tmp2; |
| 119 | |
| 120 | tmp1 = -4096UL; |
| 121 | /* FIXME: copy with reduced length. */ |
| 122 | asm volatile( |
| 123 | "0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n" |
| 124 | " jz 2f\n" |
| 125 | "1:"ALR" %0,%3\n" |
| 126 | " "SLR" %1,%3\n" |
| 127 | " "SLR" %2,%3\n" |
| 128 | " j 0b\n" |
| 129 | "2:"SLR" %0,%0\n" |
| 130 | "3: \n" |
| 131 | EX_TABLE(0b,3b) |
| 132 | : "+a" (size), "+a" (to), "+a" (from), "+a" (tmp1), "=a" (tmp2) |
| 133 | : "d" (reg0) : "cc", "memory"); |
| 134 | return size; |
| 135 | } |
| 136 | |
| 137 | size_t clear_user_mvcos(size_t size, void __user *to) |
| 138 | { |
| 139 | register unsigned long reg0 asm("0") = 0x810000UL; |
| 140 | unsigned long tmp1, tmp2; |
| 141 | |
| 142 | tmp1 = -4096UL; |
| 143 | asm volatile( |
| 144 | "0: .insn ss,0xc80000000000,0(%0,%1),0(%4),0\n" |
| 145 | " jz 4f\n" |
| 146 | "1:"ALR" %0,%2\n" |
| 147 | " "SLR" %1,%2\n" |
| 148 | " j 0b\n" |
| 149 | "2: la %3,4095(%1)\n"/* %4 = to + 4095 */ |
| 150 | " nr %3,%2\n" /* %4 = (to + 4095) & -4096 */ |
| 151 | " "SLR" %3,%1\n" |
| 152 | " "CLR" %0,%3\n" /* copy crosses next page boundary? */ |
| 153 | " jnh 5f\n" |
| 154 | "3: .insn ss,0xc80000000000,0(%3,%1),0(%4),0\n" |
| 155 | " "SLR" %0,%3\n" |
| 156 | " j 5f\n" |
| 157 | "4:"SLR" %0,%0\n" |
| 158 | "5: \n" |
| 159 | EX_TABLE(0b,2b) EX_TABLE(3b,5b) |
| 160 | : "+a" (size), "+a" (to), "+a" (tmp1), "=a" (tmp2) |
| 161 | : "a" (empty_zero_page), "d" (reg0) : "cc", "memory"); |
| 162 | return size; |
| 163 | } |
| 164 | |
Gerald Schaefer | 6c2a9e6 | 2006-09-20 15:59:44 +0200 | [diff] [blame] | 165 | extern size_t strnlen_user_std(size_t, const char __user *); |
| 166 | extern size_t strncpy_from_user_std(size_t, const char __user *, char *); |
| 167 | extern int futex_atomic_op(int, int __user *, int, int *); |
| 168 | extern int futex_atomic_cmpxchg(int __user *, int, int); |
| 169 | |
| 170 | struct uaccess_ops uaccess_mvcos = { |
Gerald Schaefer | 59f35d5 | 2006-12-04 15:40:45 +0100 | [diff] [blame] | 171 | .copy_from_user = copy_from_user_mvcos_check, |
| 172 | .copy_from_user_small = copy_from_user_std, |
| 173 | .copy_to_user = copy_to_user_mvcos_check, |
| 174 | .copy_to_user_small = copy_to_user_std, |
Gerald Schaefer | 6c2a9e6 | 2006-09-20 15:59:44 +0200 | [diff] [blame] | 175 | .copy_in_user = copy_in_user_mvcos, |
| 176 | .clear_user = clear_user_mvcos, |
| 177 | .strnlen_user = strnlen_user_std, |
| 178 | .strncpy_from_user = strncpy_from_user_std, |
| 179 | .futex_atomic_op = futex_atomic_op, |
| 180 | .futex_atomic_cmpxchg = futex_atomic_cmpxchg, |
| 181 | }; |