projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| b886d83c | 1 | /* SPDX-License-Identifier: GPL-2.0-only */ |
| 79e1dd05 | 2 | |
| 94ea9c05 | 3 | #include <linux/export.h> |
| 79e1dd05 | 4 | #include <linux/linkage.h> |
| 6d12c8d3 PZ |
5 | #include <asm/percpu.h> |
| 6 | #include <asm/processor-flags.h> | |
| 79e1dd05 | 7 | |
| 79e1dd05 AV |
8 | .text |
| 9 | ||
| 6d12c8d3 PZ |
10 | #ifndef CONFIG_X86_CMPXCHG64 |
| 11 | ||
| 79e1dd05 | 12 | /* |
| 6d12c8d3 PZ |
13 | * Emulate 'cmpxchg8b (%esi)' on UP |
| 14 | * | |
| 79e1dd05 AV |
15 | * Inputs: |
| 16 | * %esi : memory location to compare | |
| 17 | * %eax : low 32 bits of old value | |
| 18 | * %edx : high 32 bits of old value | |
| 19 | * %ebx : low 32 bits of new value | |
| 20 | * %ecx : high 32 bits of new value | |
| 21 | */ | |
| 6dcc5627 | 22 | SYM_FUNC_START(cmpxchg8b_emu) |
| 79e1dd05 | 23 | |
| 131484c8 | 24 | pushfl |
| 79e1dd05 AV |
25 | cli |
| 26 | ||
| 59bec00a | 27 | cmpl (%esi), %eax |
| 6d12c8d3 PZ |
28 | jne .Lnot_same |
| 29 | cmpl 4(%esi), %edx | |
| 30 | jne .Lnot_same | |
| 31 | ||
| 59bec00a | 32 | movl %ebx, (%esi) |
| 6d12c8d3 | 33 | movl %ecx, 4(%esi) |
| 79e1dd05 | 34 | |
| 6d12c8d3 | 35 | orl $X86_EFLAGS_ZF, (%esp) |
| 79e1dd05 | 36 | |
| 131484c8 | 37 | popfl |
| f94909ce | 38 | RET |
| 79e1dd05 | 39 | |
| 5f1d919a | 40 | .Lnot_same: |
| 59bec00a | 41 | movl (%esi), %eax |
| 6d12c8d3 PZ |
42 | movl 4(%esi), %edx |
| 43 | ||
| 44 | andl $(~X86_EFLAGS_ZF), (%esp) | |
| 79e1dd05 | 45 | |
| 131484c8 | 46 | popfl |
| f94909ce | 47 | RET |
| 79e1dd05 | 48 | |
| 6dcc5627 | 49 | SYM_FUNC_END(cmpxchg8b_emu) |
| 784d5699 | 50 | EXPORT_SYMBOL(cmpxchg8b_emu) |
| 6d12c8d3 PZ |
51 | |
| 52 | #endif | |
| 53 | ||
| 54 | #ifndef CONFIG_UML | |
| 55 | ||
| 59bec00a UB |
56 | /* |
| 57 | * Emulate 'cmpxchg8b %fs:(%rsi)' | |
| 58 | * | |
| 59 | * Inputs: | |
| 60 | * %esi : memory location to compare | |
| 61 | * %eax : low 32 bits of old value | |
| 62 | * %edx : high 32 bits of old value | |
| 63 | * %ebx : low 32 bits of new value | |
| 64 | * %ecx : high 32 bits of new value | |
| 65 | * | |
| 66 | * Notably this is not LOCK prefixed and is not safe against NMIs | |
| 67 | */ | |
| 6d12c8d3 PZ |
68 | SYM_FUNC_START(this_cpu_cmpxchg8b_emu) |
| 69 | ||
| 70 | pushfl | |
| 71 | cli | |
| 72 | ||
| 59bec00a | 73 | cmpl __percpu (%esi), %eax |
| 6d12c8d3 | 74 | jne .Lnot_same2 |
| 59bec00a | 75 | cmpl __percpu 4(%esi), %edx |
| 6d12c8d3 PZ |
76 | jne .Lnot_same2 |
| 77 | ||
| 59bec00a UB |
78 | movl %ebx, __percpu (%esi) |
| 79 | movl %ecx, __percpu 4(%esi) | |
| 6d12c8d3 PZ |
80 | |
| 81 | orl $X86_EFLAGS_ZF, (%esp) | |
| 82 | ||
| 83 | popfl | |
| 84 | RET | |
| 85 | ||
| 86 | .Lnot_same2: | |
| 59bec00a UB |
87 | movl __percpu (%esi), %eax |
| 88 | movl __percpu 4(%esi), %edx | |
| 6d12c8d3 PZ |
89 | |
| 90 | andl $(~X86_EFLAGS_ZF), (%esp) | |
| 91 | ||
| 92 | popfl | |
| 93 | RET | |
| 94 | ||
| 95 | SYM_FUNC_END(this_cpu_cmpxchg8b_emu) | |
| 96 | ||
| 97 | #endif |