summaryrefslogtreecommitdiff
path: root/src/arch/x86/isa/insts/general_purpose/system_calls.py
blob: d6f1a39bf89cf6dfb5b43e5137512f353bd45213 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
# Copyright (c) 2007 The Hewlett-Packard Development Company
# All rights reserved.
#
# The license below extends only to copyright in the software and shall
# not be construed as granting a license to any other intellectual
# property including but not limited to intellectual property relating
# to a hardware implementation of the functionality of the software
# licensed hereunder.  You may use the software subject to the license
# terms below provided that you ensure that this notice is replicated
# unmodified and in its entirety in all distributions of the software,
# modified or unmodified, in source code or in binary form.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met: redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer;
# redistributions in binary form must reproduce the above copyright
# notice, this list of conditions and the following disclaimer in the
# documentation and/or other materials provided with the distribution;
# neither the name of the copyright holders nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
# Authors: Gabe Black

microcode = '''
def macroop SYSCALL_64
{
    # All 1s.
    limm t1, "(uint64_t)(-1)", dataSize=8

    # Save the next RIP.
    rdip rcx
    
    # Stick rflags with RF masked into r11.
    rflags t2
    limm t3, "~RFBit", dataSize=8
    and r11, t2, t3, dataSize=8

    rdval t3, star
    srli t3, t3, 32, dataSize=8
    andi t3, t3, 0xFC, dataSize=1

    # Set up CS.
    wrsel cs, t3
    wrbase cs, t0, dataSize=8
    wrlimit cs, t1, dataSize=4
    # Not writable, read/execute-able, not expandDown,
    # dpl=0, defaultSize=0, long mode
    limm t4, ((0 << 0)  | (0  << 2)  | (0 << 3)   | \
              (1 << 4)  | (0  << 5)  | (1 << 6)   | \
              (1 << 7)  | (10 << 8)  | (0 << 12)  | \
              (1 << 13) | (0  << 14) | (1 << 15)), dataSize=8
    wrattr cs, t4

    # Set up SS.
    addi t3, t3, 8
    wrsel ss, t3
    wrbase ss, t0, dataSize=8
    wrlimit ss, t1, dataSize=4
    # Writable, readable, not expandDown,
    # dpl=0, defaultSize=0, not long mode
    limm t4, ((0 << 0)  | (0  << 2)  | (1 << 3)   | \
              (0 << 4)  | (0  << 5)  | (1 << 6)   | \
              (1 << 7)  | (2  << 8)  | (1 << 12)  | \
              (1 << 13) | (0  << 14) | (1 << 15)), dataSize=8
    wrattr ss, t4

    # Set the new rip.
    rdval t7, lstar, dataSize=8
    wrip t0, t7, dataSize=8

    # Mask the flags against sf_mask and leave RF turned off.
    rdval t3, sf_mask, dataSize=8
    xor t3, t3, t1, dataSize=8
    and t3, t3, r11, dataSize=8
    wrflags t3, t0
};

def macroop SYSCALL_COMPAT
{
    # All 1s.
    limm t1, "(uint64_t)(-1)", dataSize=8

    # Save the next RIP.
    rdip rcx
    
    # Stick rflags with RF masked into r11.
    rflags t2
    limm t3, "~RFBit", dataSize=8
    and r11, t2, t3, dataSize=8

    rdval t3, star
    srli t3, t3, 32, dataSize=8
    andi t3, t3, 0xFC, dataSize=1

    # Set up CS.
    wrsel cs, t3
    wrbase cs, t0, dataSize=8
    wrlimit cs, t1, dataSize=4
    # Not writable, read/execute-able, not expandDown,
    # dpl=0, defaultSize=0, long mode
    limm t4, ((0 << 0)  | (0  << 2)  | (0 << 3)   | \
              (1 << 4)  | (0  << 5)  | (1 << 6)   | \
              (1 << 7)  | (10 << 8)  | (0 << 12)  | \
              (1 << 13) | (0  << 14) | (1 << 15)), dataSize=8
    wrattr cs, t4

    # Set up SS.
    addi t3, t3, 8
    wrsel ss, t3
    wrbase ss, t0, dataSize=8
    wrlimit ss, t1, dataSize=4
    # Writable, readable, not expandDown,
    # dpl=0, defaultSize=0, not long mode
    limm t4, ((0 << 0)  | (0  << 2)  | (1 << 3)   | \
              (0 << 4)  | (0  << 5)  | (1 << 6)   | \
              (1 << 7)  | (2  << 8)  | (1 << 12)  | \
              (1 << 13) | (0  << 14) | (1 << 15)), dataSize=8
    wrattr ss, t4

    # Set the new rip.
    rdval t7, cstar
    wrip t0, t7

    # Mask the flags against sf_mask and leave RF turned off.
    rdval t3, sf_mask, dataSize=8
    xor t3, t3, t1, dataSize=8
    and t3, t3, r11, dataSize=8
    wrflags t3, t0
};

def macroop SYSCALL_LEGACY
{
    panic "The syscall instruction isn't implemented in legacy mode."
};

def macroop SYSRET_TO_64
{
    # All 1s.
    limm t1, "(uint64_t)(-1)", dataSize=8

    rdval t3, star
    srli t3, t3, 48, dataSize=8
    ori t3, t3, 3, dataSize=1

    # Set rflags to r11 with RF and VM cleared.
    limm t4, "~(RFBit | VMBit)", dataSize=8
    and t4, t4, r11, dataSize=8
    wrflags t4, t0

    # Set up CS.
    addi t4, t3, 16, dataSize=8
    wrsel cs, t4
    wrbase cs, t0, dataSize=8
    wrlimit cs, t1, dataSize=4
    # Not writable, read/execute-able, not expandDown,
    # dpl=3, defaultSize=0, long mode
    limm t4, ((3 << 0)  | (0  << 2)  | (0 << 3)   | \
              (1 << 4)  | (0  << 5)  | (1 << 6)   | \
              (1 << 7)  | (10 << 8)  | (0 << 12)  | \
              (1 << 13) | (0  << 14) | (1 << 15)), dataSize=8
    wrattr cs, t4

    # Only the selector is changed for SS.
    addi t4, t3, 8, dataSize=8
    wrsel ss, t4

    # Set the RIP back.
    wrip rcx, t0, dataSize=8
};

def macroop SYSRET_TO_COMPAT
{
    # All 1s.
    limm t1, "(uint64_t)(-1)", dataSize=8

    rdval t3, star
    srli t3, t3, 48, dataSize=8
    ori t3, t3, 3, dataSize=1

    # Set rflags to r11 with RF and VM cleared.
    limm t4, "~(RFBit | VMBit)", dataSize=8
    and t4, t4, r11, dataSize=8
    wrflags t4, t0

    # Set up CS.
    wrsel cs, t3
    wrbase cs, t0, dataSize=8
    wrlimit cs, t1, dataSize=4
    # Not writable, read/execute-able, not expandDown,
    # dpl=3, defaultSize=1, not long mode
    limm t4, ((3 << 0)  | (0  << 2)  | (0 << 3)   | \
              (1 << 4)  | (0  << 5)  | (1 << 6)   | \
              (1 << 7)  | (10 << 8)  | (0 << 12)  | \
              (1 << 13) | (0  << 14) | (1 << 15)), dataSize=8
    wrattr cs, t4

    # Only the selector is changed for SS.
    addi t4, t3, 8, dataSize=8
    wrsel ss, t4

    # Set the RIP back.
    wrip rcx, t0, dataSize=8
};

def macroop SYSRET_NON_64
{
    panic "The sysret instruction isn't implemented in legacy mode."
};
'''
#let {{
#    class SYSENTER(Inst):
#       "GenFault ${new UnimpInstFault}"
#    class SYSEXIT(Inst):
#       "GenFault ${new UnimpInstFault}"
#}};