1 /*
2 * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
3 * Licensed under the GPL
4 */
5
6 #ifndef __UM_PROCESSOR_I386_H
7 #define __UM_PROCESSOR_I386_H
8
9 #include <linux/string.h>
10 #include <asm/segment.h>
11 #include <asm/ldt.h>
12
13 extern int host_has_cmov;
14
15 struct uml_tls_struct {
16 struct user_desc tls;
17 unsigned flushed:1;
18 unsigned present:1;
19 };
20
21 struct arch_thread {
22 struct uml_tls_struct tls_array[GDT_ENTRY_TLS_ENTRIES];
23 unsigned long debugregs[8];
24 int debugregs_seq;
25 struct faultinfo faultinfo;
26 };
27
28 #define INIT_ARCH_THREAD { \
29 .tls_array = { [ 0 ... GDT_ENTRY_TLS_ENTRIES - 1 ] = \
30 { .present = 0, .flushed = 0 } }, \
31 .debugregs = { [ 0 ... 7 ] = 0 }, \
32 .debugregs_seq = 0, \
33 .faultinfo = { 0, 0, 0 } \
34 }
35
arch_flush_thread(struct arch_thread * thread)36 static inline void arch_flush_thread(struct arch_thread *thread)
37 {
38 /* Clear any TLS still hanging */
39 memset(&thread->tls_array, 0, sizeof(thread->tls_array));
40 }
41
arch_copy_thread(struct arch_thread * from,struct arch_thread * to)42 static inline void arch_copy_thread(struct arch_thread *from,
43 struct arch_thread *to)
44 {
45 memcpy(&to->tls_array, &from->tls_array, sizeof(from->tls_array));
46 }
47
48 #include <asm/user.h>
49
50 /* REP NOP (PAUSE) is a good thing to insert into busy-wait loops. */
rep_nop(void)51 static inline void rep_nop(void)
52 {
53 __asm__ __volatile__("rep;nop": : :"memory");
54 }
55
56 #define cpu_relax() rep_nop()
57
58 /*
59 * Default implementation of macro that returns current
60 * instruction pointer ("program counter"). Stolen
61 * from asm-i386/processor.h
62 */
63 #define current_text_addr() \
64 ({ void *pc; __asm__("movl $1f,%0\n1:":"=g" (pc)); pc; })
65
66 #endif
67