Merge tag 'pull-la-20220814' of https://gitlab.com/rth7680/qemu into staging
[qemu.git] / linux-user / openrisc / signal.c
1 /*
2 * Emulation of Linux signals
3 *
4 * Copyright (c) 2003 Fabrice Bellard
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
18 */
19 #include "qemu/osdep.h"
20 #include "qemu.h"
21 #include "user-internals.h"
22 #include "signal-common.h"
23 #include "linux-user/trace.h"
24
25 typedef struct target_sigcontext {
26 struct target_pt_regs regs;
27 abi_ulong oldmask;
28 } target_sigcontext;
29
30 typedef struct target_ucontext {
31 abi_ulong tuc_flags;
32 abi_ulong tuc_link;
33 target_stack_t tuc_stack;
34 target_sigcontext tuc_mcontext;
35 target_sigset_t tuc_sigmask; /* mask last for extensibility */
36 } target_ucontext;
37
38 typedef struct target_rt_sigframe {
39 struct target_siginfo info;
40 target_ucontext uc;
41 } target_rt_sigframe;
42
43 static void restore_sigcontext(CPUOpenRISCState *env, target_sigcontext *sc)
44 {
45 int i;
46 abi_ulong v;
47
48 for (i = 0; i < 32; ++i) {
49 __get_user(v, &sc->regs.gpr[i]);
50 cpu_set_gpr(env, i, v);
51 }
52 __get_user(env->pc, &sc->regs.pc);
53
54 /* Make sure the supervisor flag is clear. */
55 __get_user(v, &sc->regs.sr);
56 cpu_set_sr(env, v & ~SR_SM);
57 }
58
59 /* Set up a signal frame. */
60
61 static void setup_sigcontext(target_sigcontext *sc, CPUOpenRISCState *env)
62 {
63 int i;
64
65 for (i = 0; i < 32; ++i) {
66 __put_user(cpu_get_gpr(env, i), &sc->regs.gpr[i]);
67 }
68
69 __put_user(env->pc, &sc->regs.pc);
70 __put_user(cpu_get_sr(env), &sc->regs.sr);
71 }
72
73 static inline abi_ulong get_sigframe(struct target_sigaction *ka,
74 CPUOpenRISCState *env,
75 size_t frame_size)
76 {
77 target_ulong sp = get_sp_from_cpustate(env);
78
79 /* Honor redzone now. If we swap to signal stack, no need to waste
80 * the 128 bytes by subtracting afterward.
81 */
82 sp -= 128;
83
84 sp = target_sigsp(sp, ka);
85 sp -= frame_size;
86 sp = QEMU_ALIGN_DOWN(sp, 4);
87
88 return sp;
89 }
90
91 void setup_rt_frame(int sig, struct target_sigaction *ka,
92 target_siginfo_t *info,
93 target_sigset_t *set, CPUOpenRISCState *env)
94 {
95 abi_ulong frame_addr;
96 target_rt_sigframe *frame;
97 int i;
98
99 frame_addr = get_sigframe(ka, env, sizeof(*frame));
100 trace_user_setup_rt_frame(env, frame_addr);
101 if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0)) {
102 goto give_sigsegv;
103 }
104
105 if (ka->sa_flags & SA_SIGINFO) {
106 tswap_siginfo(&frame->info, info);
107 }
108
109 __put_user(0, &frame->uc.tuc_flags);
110 __put_user(0, &frame->uc.tuc_link);
111
112 target_save_altstack(&frame->uc.tuc_stack, env);
113 setup_sigcontext(&frame->uc.tuc_mcontext, env);
114 for (i = 0; i < TARGET_NSIG_WORDS; ++i) {
115 __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
116 }
117
118 /* Set up registers for signal handler */
119 cpu_set_gpr(env, 9, default_rt_sigreturn);
120 cpu_set_gpr(env, 3, sig);
121 cpu_set_gpr(env, 4, frame_addr + offsetof(target_rt_sigframe, info));
122 cpu_set_gpr(env, 5, frame_addr + offsetof(target_rt_sigframe, uc));
123 cpu_set_gpr(env, 1, frame_addr);
124
125 /* For debugging convenience, set ppc to the insn that faulted. */
126 env->ppc = env->pc;
127 /* When setting the PC for the signal handler, exit delay slot. */
128 env->pc = ka->_sa_handler;
129 env->dflag = 0;
130 return;
131
132 give_sigsegv:
133 unlock_user_struct(frame, frame_addr, 1);
134 force_sigsegv(sig);
135 }
136
137 long do_rt_sigreturn(CPUOpenRISCState *env)
138 {
139 abi_ulong frame_addr = get_sp_from_cpustate(env);
140 target_rt_sigframe *frame;
141 sigset_t set;
142
143 trace_user_do_rt_sigreturn(env, 0);
144 if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1)) {
145 goto badframe;
146 }
147 if (frame_addr & 3) {
148 goto badframe;
149 }
150
151 target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
152 set_sigmask(&set);
153
154 restore_sigcontext(env, &frame->uc.tuc_mcontext);
155 target_restore_altstack(&frame->uc.tuc_stack, env);
156
157 unlock_user_struct(frame, frame_addr, 0);
158 return cpu_get_gpr(env, 11);
159
160 badframe:
161 unlock_user_struct(frame, frame_addr, 0);
162 force_sig(TARGET_SIGSEGV);
163 return 0;
164 }
165
166 void setup_sigtramp(abi_ulong sigtramp_page)
167 {
168 uint32_t *tramp = lock_user(VERIFY_WRITE, sigtramp_page, 8, 0);
169 assert(tramp != NULL);
170
171 /* This is l.ori r11,r0,__NR_sigreturn; l.sys 1 */
172 __put_user(0xa9600000 | TARGET_NR_rt_sigreturn, tramp + 0);
173 __put_user(0x20000001, tramp + 1);
174
175 default_rt_sigreturn = sigtramp_page;
176 unlock_user(tramp, sigtramp_page, 8);
177 }