xref: /openbmc/linux/arch/x86/um/os-Linux/registers.c (revision 293d5b43)
1 /*
2  * Copyright (C) 2004 PathScale, Inc
3  * Copyright (C) 2004 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
4  * Licensed under the GPL
5  */
6 
7 #include <errno.h>
8 #include <sys/ptrace.h>
9 #ifdef __i386__
10 #include <sys/user.h>
11 #endif
12 #include <longjmp.h>
13 #include <sysdep/ptrace_user.h>
14 #include <sys/uio.h>
15 #include <asm/sigcontext.h>
16 #include <linux/elf.h>
17 
18 int have_xstate_support;
19 
20 int save_i387_registers(int pid, unsigned long *fp_regs)
21 {
22 	if (ptrace(PTRACE_GETFPREGS, pid, 0, fp_regs) < 0)
23 		return -errno;
24 	return 0;
25 }
26 
27 int save_fp_registers(int pid, unsigned long *fp_regs)
28 {
29 	struct iovec iov;
30 
31 	if (have_xstate_support) {
32 		iov.iov_base = fp_regs;
33 		iov.iov_len = sizeof(struct _xstate);
34 		if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
35 			return -errno;
36 		return 0;
37 	} else {
38 		return save_i387_registers(pid, fp_regs);
39 	}
40 }
41 
42 int restore_i387_registers(int pid, unsigned long *fp_regs)
43 {
44 	if (ptrace(PTRACE_SETFPREGS, pid, 0, fp_regs) < 0)
45 		return -errno;
46 	return 0;
47 }
48 
49 int restore_fp_registers(int pid, unsigned long *fp_regs)
50 {
51 	struct iovec iov;
52 
53 	if (have_xstate_support) {
54 		iov.iov_base = fp_regs;
55 		iov.iov_len = sizeof(struct _xstate);
56 		if (ptrace(PTRACE_SETREGSET, pid, NT_X86_XSTATE, &iov) < 0)
57 			return -errno;
58 		return 0;
59 	} else {
60 		return restore_i387_registers(pid, fp_regs);
61 	}
62 }
63 
64 #ifdef __i386__
65 int have_fpx_regs = 1;
66 int save_fpx_registers(int pid, unsigned long *fp_regs)
67 {
68 	if (ptrace(PTRACE_GETFPXREGS, pid, 0, fp_regs) < 0)
69 		return -errno;
70 	return 0;
71 }
72 
73 int restore_fpx_registers(int pid, unsigned long *fp_regs)
74 {
75 	if (ptrace(PTRACE_SETFPXREGS, pid, 0, fp_regs) < 0)
76 		return -errno;
77 	return 0;
78 }
79 
80 int get_fp_registers(int pid, unsigned long *regs)
81 {
82 	if (have_fpx_regs)
83 		return save_fpx_registers(pid, regs);
84 	else
85 		return save_fp_registers(pid, regs);
86 }
87 
88 int put_fp_registers(int pid, unsigned long *regs)
89 {
90 	if (have_fpx_regs)
91 		return restore_fpx_registers(pid, regs);
92 	else
93 		return restore_fp_registers(pid, regs);
94 }
95 
96 void arch_init_registers(int pid)
97 {
98 	struct user_fpxregs_struct fpx_regs;
99 	int err;
100 
101 	err = ptrace(PTRACE_GETFPXREGS, pid, 0, &fpx_regs);
102 	if (!err)
103 		return;
104 
105 	if (errno != EIO)
106 		panic("check_ptrace : PTRACE_GETFPXREGS failed, errno = %d",
107 		      errno);
108 
109 	have_fpx_regs = 0;
110 }
111 #else
112 
113 int get_fp_registers(int pid, unsigned long *regs)
114 {
115 	return save_fp_registers(pid, regs);
116 }
117 
118 int put_fp_registers(int pid, unsigned long *regs)
119 {
120 	return restore_fp_registers(pid, regs);
121 }
122 
123 void arch_init_registers(int pid)
124 {
125 	struct _xstate fp_regs;
126 	struct iovec iov;
127 
128 	iov.iov_base = &fp_regs;
129 	iov.iov_len = sizeof(struct _xstate);
130 	if (ptrace(PTRACE_GETREGSET, pid, NT_X86_XSTATE, &iov) == 0)
131 		have_xstate_support = 1;
132 }
133 #endif
134 
135 unsigned long get_thread_reg(int reg, jmp_buf *buf)
136 {
137 	switch (reg) {
138 #ifdef __i386__
139 	case HOST_IP:
140 		return buf[0]->__eip;
141 	case HOST_SP:
142 		return buf[0]->__esp;
143 	case HOST_BP:
144 		return buf[0]->__ebp;
145 #else
146 	case HOST_IP:
147 		return buf[0]->__rip;
148 	case HOST_SP:
149 		return buf[0]->__rsp;
150 	case HOST_BP:
151 		return buf[0]->__rbp;
152 #endif
153 	default:
154 		printk(UM_KERN_ERR "get_thread_regs - unknown register %d\n",
155 		       reg);
156 		return 0;
157 	}
158 }
159