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
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
|
/*
* rtrap.S: Return from Sparc trap low-level code.
*
* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
*/
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/psr.h>
#include <asm/asi.h>
#include <asm/smp.h>
#include <asm/contregs.h>
#include <asm/winmacro.h>
#include <asm/asmmacro.h>
#include <asm/thread_info.h>
#define t_psr l0
#define t_pc l1
#define t_npc l2
#define t_wim l3
#define twin_tmp1 l4
#define glob_tmp g4
#define curptr g6
/* 7 WINDOW SPARC PATCH INSTRUCTIONS */
.globl rtrap_7win_patch1, rtrap_7win_patch2, rtrap_7win_patch3
.globl rtrap_7win_patch4, rtrap_7win_patch5
rtrap_7win_patch1: srl %t_wim, 0x6, %glob_tmp
rtrap_7win_patch2: and %glob_tmp, 0x7f, %glob_tmp
rtrap_7win_patch3: srl %g1, 7, %g2
rtrap_7win_patch4: srl %g2, 6, %g2
rtrap_7win_patch5: and %g1, 0x7f, %g1
/* END OF PATCH INSTRUCTIONS */
/* We need to check for a few things which are:
* 1) The need to call schedule() because this
* processes quantum is up.
* 2) Pending signals for this process, if any
* exist we need to call do_signal() to do
* the needy.
*
* Else we just check if the rett would land us
* in an invalid window, if so we need to grab
* it off the user/kernel stack first.
*/
.globl ret_trap_entry, rtrap_patch1, rtrap_patch2
.globl rtrap_patch3, rtrap_patch4, rtrap_patch5
.globl ret_trap_lockless_ipi
ret_trap_entry:
ret_trap_lockless_ipi:
andcc %t_psr, PSR_PS, %g0
sethi %hi(PSR_SYSCALL), %g1
be 1f
andn %t_psr, %g1, %t_psr
wr %t_psr, 0x0, %psr
b ret_trap_kernel
nop
1:
ld [%curptr + TI_FLAGS], %g2
andcc %g2, (_TIF_NEED_RESCHED), %g0
be signal_p
nop
call schedule
nop
ld [%curptr + TI_FLAGS], %g2
signal_p:
andcc %g2, _TIF_DO_NOTIFY_RESUME_MASK, %g0
bz,a ret_trap_continue
ld [%sp + STACKFRAME_SZ + PT_PSR], %t_psr
mov %g2, %o2
mov %l5, %o1
call do_notify_resume
add %sp, STACKFRAME_SZ, %o0 ! pt_regs ptr
b signal_p
ld [%curptr + TI_FLAGS], %g2
ret_trap_continue:
sethi %hi(PSR_SYSCALL), %g1
andn %t_psr, %g1, %t_psr
wr %t_psr, 0x0, %psr
WRITE_PAUSE
ld [%curptr + TI_W_SAVED], %twin_tmp1
orcc %g0, %twin_tmp1, %g0
be ret_trap_nobufwins
nop
wr %t_psr, PSR_ET, %psr
WRITE_PAUSE
mov 1, %o1
call try_to_clear_window_buffer
add %sp, STACKFRAME_SZ, %o0
b signal_p
ld [%curptr + TI_FLAGS], %g2
ret_trap_nobufwins:
/* Load up the user's out registers so we can pull
* a window from the stack, if necessary.
*/
LOAD_PT_INS(sp)
/* If there are already live user windows in the
* set we can return from trap safely.
*/
ld [%curptr + TI_UWINMASK], %twin_tmp1
orcc %g0, %twin_tmp1, %g0
bne ret_trap_userwins_ok
nop
/* Calculate new %wim, we have to pull a register
* window from the users stack.
*/
ret_trap_pull_one_window:
rd %wim, %t_wim
sll %t_wim, 0x1, %twin_tmp1
rtrap_patch1: srl %t_wim, 0x7, %glob_tmp
or %glob_tmp, %twin_tmp1, %glob_tmp
rtrap_patch2: and %glob_tmp, 0xff, %glob_tmp
wr %glob_tmp, 0x0, %wim
/* Here comes the architecture specific
* branch to the user stack checking routine
* for return from traps.
*/
b srmmu_rett_stackchk
andcc %fp, 0x7, %g0
ret_trap_userwins_ok:
LOAD_PT_PRIV(sp, t_psr, t_pc, t_npc)
or %t_pc, %t_npc, %g2
andcc %g2, 0x3, %g0
sethi %hi(PSR_SYSCALL), %g2
be 1f
andn %t_psr, %g2, %t_psr
b ret_trap_unaligned_pc
add %sp, STACKFRAME_SZ, %o0
1:
LOAD_PT_YREG(sp, g1)
LOAD_PT_GLOBALS(sp)
wr %t_psr, 0x0, %psr
WRITE_PAUSE
jmp %t_pc
rett %t_npc
ret_trap_unaligned_pc:
ld [%sp + STACKFRAME_SZ + PT_PC], %o1
ld [%sp + STACKFRAME_SZ + PT_NPC], %o2
ld [%sp + STACKFRAME_SZ + PT_PSR], %o3
wr %t_wim, 0x0, %wim ! or else...
wr %t_psr, PSR_ET, %psr
WRITE_PAUSE
call do_memaccess_unaligned
nop
b signal_p
ld [%curptr + TI_FLAGS], %g2
ret_trap_kernel:
/* Will the rett land us in the invalid window? */
mov 2, %g1
sll %g1, %t_psr, %g1
rtrap_patch3: srl %g1, 8, %g2
or %g1, %g2, %g1
rd %wim, %g2
andcc %g2, %g1, %g0
be 1f ! Nope, just return from the trap
sll %g2, 0x1, %g1
/* We have to grab a window before returning. */
rtrap_patch4: srl %g2, 7, %g2
or %g1, %g2, %g1
rtrap_patch5: and %g1, 0xff, %g1
wr %g1, 0x0, %wim
/* Grrr, make sure we load from the right %sp... */
LOAD_PT_ALL(sp, t_psr, t_pc, t_npc, g1)
restore %g0, %g0, %g0
LOAD_WINDOW(sp)
b 2f
save %g0, %g0, %g0
/* Reload the entire frame in case this is from a
* kernel system call or whatever...
*/
1:
LOAD_PT_ALL(sp, t_psr, t_pc, t_npc, g1)
2:
sethi %hi(PSR_SYSCALL), %twin_tmp1
andn %t_psr, %twin_tmp1, %t_psr
wr %t_psr, 0x0, %psr
WRITE_PAUSE
jmp %t_pc
rett %t_npc
ret_trap_user_stack_is_bolixed:
wr %t_wim, 0x0, %wim
wr %t_psr, PSR_ET, %psr
WRITE_PAUSE
call window_ret_fault
add %sp, STACKFRAME_SZ, %o0
b signal_p
ld [%curptr + TI_FLAGS], %g2
.globl srmmu_rett_stackchk
srmmu_rett_stackchk:
bne ret_trap_user_stack_is_bolixed
sethi %hi(PAGE_OFFSET), %g1
cmp %g1, %fp
bleu ret_trap_user_stack_is_bolixed
mov AC_M_SFSR, %g1
LEON_PI(lda [%g1] ASI_LEON_MMUREGS, %g0)
SUN_PI_(lda [%g1] ASI_M_MMUREGS, %g0)
LEON_PI(lda [%g0] ASI_LEON_MMUREGS, %g1)
SUN_PI_(lda [%g0] ASI_M_MMUREGS, %g1)
or %g1, 0x2, %g1
LEON_PI(sta %g1, [%g0] ASI_LEON_MMUREGS)
SUN_PI_(sta %g1, [%g0] ASI_M_MMUREGS)
restore %g0, %g0, %g0
LOAD_WINDOW(sp)
save %g0, %g0, %g0
andn %g1, 0x2, %g1
LEON_PI(sta %g1, [%g0] ASI_LEON_MMUREGS)
SUN_PI_(sta %g1, [%g0] ASI_M_MMUREGS)
mov AC_M_SFAR, %g2
LEON_PI(lda [%g2] ASI_LEON_MMUREGS, %g2)
SUN_PI_(lda [%g2] ASI_M_MMUREGS, %g2)
mov AC_M_SFSR, %g1
LEON_PI(lda [%g1] ASI_LEON_MMUREGS, %g1)
SUN_PI_(lda [%g1] ASI_M_MMUREGS, %g1)
andcc %g1, 0x2, %g0
be ret_trap_userwins_ok
nop
b,a ret_trap_user_stack_is_bolixed
|
