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21#include <linux/linkage.h>
22#include <linux/syscalls.h>
23#include <linux/tracehook.h>
24#include <asm/registers.h>
25#include <asm/thread_info.h>
26#include <asm/unistd.h>
27#include <asm/uaccess.h>
28#include <asm/ucontext.h>
29#include <asm/cacheflush.h>
30#include <asm/signal.h>
31#include <asm/vdso.h>
32
33struct rt_sigframe {
34 unsigned long tramp[2];
35 struct siginfo info;
36 struct ucontext uc;
37};
38
39static void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
40 size_t frame_size)
41{
42 unsigned long sp = regs->r29;
43
44
45 if (on_sig_stack(sp) && !likely(on_sig_stack(sp - frame_size)))
46 return (void __user __force *)-1UL;
47
48
49 if ((ka->sa.sa_flags & SA_ONSTACK) && (sas_ss_flags(sp) == 0))
50 sp = current->sas_ss_sp + current->sas_ss_size;
51
52 return (void __user *)((sp - frame_size) & ~(sizeof(long long) - 1));
53}
54
55static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
56{
57 unsigned long tmp;
58 int err = 0;
59
60 err |= copy_to_user(&sc->sc_regs.r0, ®s->r00,
61 32*sizeof(unsigned long));
62
63 err |= __put_user(regs->sa0, &sc->sc_regs.sa0);
64 err |= __put_user(regs->lc0, &sc->sc_regs.lc0);
65 err |= __put_user(regs->sa1, &sc->sc_regs.sa1);
66 err |= __put_user(regs->lc1, &sc->sc_regs.lc1);
67 err |= __put_user(regs->m0, &sc->sc_regs.m0);
68 err |= __put_user(regs->m1, &sc->sc_regs.m1);
69 err |= __put_user(regs->usr, &sc->sc_regs.usr);
70 err |= __put_user(regs->preds, &sc->sc_regs.p3_0);
71 err |= __put_user(regs->gp, &sc->sc_regs.gp);
72 err |= __put_user(regs->ugp, &sc->sc_regs.ugp);
73#if CONFIG_HEXAGON_ARCH_VERSION >= 4
74 err |= __put_user(regs->cs0, &sc->sc_regs.cs0);
75 err |= __put_user(regs->cs1, &sc->sc_regs.cs1);
76#endif
77 tmp = pt_elr(regs); err |= __put_user(tmp, &sc->sc_regs.pc);
78 tmp = pt_cause(regs); err |= __put_user(tmp, &sc->sc_regs.cause);
79 tmp = pt_badva(regs); err |= __put_user(tmp, &sc->sc_regs.badva);
80
81 return err;
82}
83
84static int restore_sigcontext(struct pt_regs *regs,
85 struct sigcontext __user *sc)
86{
87 unsigned long tmp;
88 int err = 0;
89
90 err |= copy_from_user(®s->r00, &sc->sc_regs.r0,
91 32 * sizeof(unsigned long));
92
93 err |= __get_user(regs->sa0, &sc->sc_regs.sa0);
94 err |= __get_user(regs->lc0, &sc->sc_regs.lc0);
95 err |= __get_user(regs->sa1, &sc->sc_regs.sa1);
96 err |= __get_user(regs->lc1, &sc->sc_regs.lc1);
97 err |= __get_user(regs->m0, &sc->sc_regs.m0);
98 err |= __get_user(regs->m1, &sc->sc_regs.m1);
99 err |= __get_user(regs->usr, &sc->sc_regs.usr);
100 err |= __get_user(regs->preds, &sc->sc_regs.p3_0);
101 err |= __get_user(regs->gp, &sc->sc_regs.gp);
102 err |= __get_user(regs->ugp, &sc->sc_regs.ugp);
103#if CONFIG_HEXAGON_ARCH_VERSION >= 4
104 err |= __get_user(regs->cs0, &sc->sc_regs.cs0);
105 err |= __get_user(regs->cs1, &sc->sc_regs.cs1);
106#endif
107 err |= __get_user(tmp, &sc->sc_regs.pc); pt_set_elr(regs, tmp);
108
109 return err;
110}
111
112
113
114
115static int setup_rt_frame(int signr, struct k_sigaction *ka, siginfo_t *info,
116 sigset_t *set, struct pt_regs *regs)
117{
118 int err = 0;
119 struct rt_sigframe __user *frame;
120 struct hexagon_vdso *vdso = current->mm->context.vdso;
121
122 frame = get_sigframe(ka, regs, sizeof(struct rt_sigframe));
123
124 if (!access_ok(VERIFY_WRITE, frame, sizeof(struct rt_sigframe)))
125 goto sigsegv;
126
127 if (copy_siginfo_to_user(&frame->info, info))
128 goto sigsegv;
129
130
131
132
133
134 err |= __put_user(0x7800d166, &frame->tramp[0]);
135 err |= __put_user(0x5400c004, &frame->tramp[1]);
136 err |= setup_sigcontext(regs, &frame->uc.uc_mcontext);
137 err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
138 err |= __save_altstack(&frame->uc.uc_stack, user_stack_pointer(regs));
139 if (err)
140 goto sigsegv;
141
142
143 regs->r0100 = ((unsigned long long)((unsigned long)&frame->info) << 32)
144 | (unsigned long long)signr;
145 regs->r02 = (unsigned long) &frame->uc;
146 regs->r31 = (unsigned long) vdso->rt_signal_trampoline;
147 pt_psp(regs) = (unsigned long) frame;
148 pt_set_elr(regs, (unsigned long)ka->sa.sa_handler);
149
150 return 0;
151
152sigsegv:
153 force_sigsegv(signr, current);
154 return -EFAULT;
155}
156
157
158
159
160static void handle_signal(int sig, siginfo_t *info, struct k_sigaction *ka,
161 struct pt_regs *regs)
162{
163
164
165
166
167
168
169 if (regs->syscall_nr >= 0) {
170 switch (regs->r00) {
171 case -ERESTART_RESTARTBLOCK:
172 case -ERESTARTNOHAND:
173 regs->r00 = -EINTR;
174 break;
175 case -ERESTARTSYS:
176 if (!(ka->sa.sa_flags & SA_RESTART)) {
177 regs->r00 = -EINTR;
178 break;
179 }
180
181 case -ERESTARTNOINTR:
182 regs->r06 = regs->syscall_nr;
183 pt_set_elr(regs, pt_elr(regs) - 4);
184 regs->r00 = regs->restart_r0;
185 break;
186 default:
187 break;
188 }
189 }
190
191
192
193
194
195
196 if (setup_rt_frame(sig, ka, info, sigmask_to_save(), regs) < 0)
197 return;
198
199 signal_delivered(sig, info, ka, regs,
200 test_thread_flag(TIF_SINGLESTEP));
201}
202
203
204
205
206void do_signal(struct pt_regs *regs)
207{
208 struct k_sigaction sigact;
209 siginfo_t info;
210 int signo;
211
212 if (!user_mode(regs))
213 return;
214
215 signo = get_signal_to_deliver(&info, &sigact, regs, NULL);
216
217 if (signo > 0) {
218 handle_signal(signo, &info, &sigact, regs);
219 return;
220 }
221
222
223
224
225
226 if (regs->syscall_nr >= 0) {
227 switch (regs->r00) {
228 case -ERESTARTNOHAND:
229 case -ERESTARTSYS:
230 case -ERESTARTNOINTR:
231 regs->r06 = regs->syscall_nr;
232 break;
233 case -ERESTART_RESTARTBLOCK:
234 regs->r06 = __NR_restart_syscall;
235 break;
236 default:
237 goto no_restart;
238 }
239 pt_set_elr(regs, pt_elr(regs) - 4);
240 regs->r00 = regs->restart_r0;
241 }
242
243no_restart:
244
245 restore_saved_sigmask();
246}
247
248
249
250
251
252asmlinkage int sys_rt_sigreturn(void)
253{
254 struct pt_regs *regs = current_pt_regs();
255 struct rt_sigframe __user *frame;
256 sigset_t blocked;
257
258
259 current_thread_info()->restart_block.fn = do_no_restart_syscall;
260
261 frame = (struct rt_sigframe __user *)pt_psp(regs);
262 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
263 goto badframe;
264 if (__copy_from_user(&blocked, &frame->uc.uc_sigmask, sizeof(blocked)))
265 goto badframe;
266
267 set_current_blocked(&blocked);
268
269 if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
270 goto badframe;
271
272
273 pt_psp(regs) = regs->r29;
274
275 regs->syscall_nr = -1;
276
277 if (restore_altstack(&frame->uc.uc_stack))
278 goto badframe;
279
280 return regs->r00;
281
282badframe:
283 force_sig(SIGSEGV, current);
284 return 0;
285}
286