Subversion Repositories HelenOS-historic

Rev

Rev 1120 | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
1120 palkovsky 1
#
2
# Copyright (C) 2001-2004 Jakub Jermar
3
# All rights reserved.
4
#
5
# Redistribution and use in source and binary forms, with or without
6
# modification, are permitted provided that the following conditions
7
# are met:
8
#
9
# - Redistributions of source code must retain the above copyright
10
#   notice, this list of conditions and the following disclaimer.
11
# - Redistributions in binary form must reproduce the above copyright
12
#   notice, this list of conditions and the following disclaimer in the
13
#   documentation and/or other materials provided with the distribution.
14
# - The name of the author may not be used to endorse or promote products
15
#   derived from this software without specific prior written permission.
16
#
17
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
#
28
 
29
.text
30
 
31
.global context_save
32
.global context_restore
33
 
34
 
35
## Save current CPU context
36
#
37
# Save CPU context to the context_t variable
38
# pointed by the 1st argument. Returns 1 in EAX.
39
#
40
context_save:
41
	movl 0(%esp),%eax	# the caller's return %eip
42
	movl 4(%esp),%edx	# address of the kernel_context variable to save context to
43
 
44
	movl %esp,0(%edx)	# %esp -> ctx->sp
45
	movl %eax,4(%edx)	# %eip -> ctx->pc
46
	movl %ebx,8(%edx)	# %ebx -> ctx->ebx
47
	movl %esi,12(%edx)	# %esi -> ctx->esi
48
	movl %edi,16(%edx)	# %edi -> ctx->edi
49
	movl %ebp,20(%edx)	# %ebp -> ctx->ebp
50
 
51
	# Save TLS
52
	movl %gs:0, %eax
53
	movl %eax, 24(%edx)     # tls -> ctx->tls
54
 
55
	xorl %eax,%eax		# context_save returns 1
56
	incl %eax
57
	ret
58
 
59
 
60
## Restore saved CPU context
61
#
62
# Restore CPU context from context_t variable
63
# pointed by the 1st argument. Returns 0 in EAX.
64
#
65
context_restore:
66
	movl 4(%esp),%eax	# address of the kernel_context variable to restore context from
67
	movl 0(%eax),%esp	# ctx->sp -> %esp
68
	movl 4(%eax),%edx	# ctx->pc -> %edx
69
	movl 8(%eax),%ebx	# ctx->ebx -> %ebx
70
	movl 12(%eax),%esi	# ctx->esi -> %esi
71
	movl 16(%eax),%edi	# ctx->edi -> %edi
72
	movl 20(%eax),%ebp	# ctx->ebp -> %ebp
73
 
74
	movl %edx,0(%esp)	# ctx->pc -> saver's return %eip
1391 palkovsky 75
 
1120 palkovsky 76
	# Set thread local storage
1391 palkovsky 77
	pushl %edi
1120 palkovsky 78
	movl 24(%eax), %eax   # Set arg1 to TLS addr
79
	movl $1, %edi         # Syscall 1
80
	int $0x30
1391 palkovsky 81
	popl %edi
1120 palkovsky 82
 
83
	xorl %eax,%eax		# context_restore returns 0
84
	ret