Commit | Line | Data |
---|---|---|
b00dc837 | 1 | /* |
1da177e4 LT |
2 | * arch/sparc64/kernel/signal.c |
3 | * | |
4 | * Copyright (C) 1991, 1992 Linus Torvalds | |
0a4949c4 | 5 | * Copyright (C) 1995, 2008 David S. Miller (davem@davemloft.net) |
1da177e4 LT |
6 | * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx) |
7 | * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be) | |
8 | * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) | |
9 | */ | |
10 | ||
09337f50 | 11 | #ifdef CONFIG_COMPAT |
1da177e4 LT |
12 | #include <linux/compat.h> /* for compat_old_sigset_t */ |
13 | #endif | |
14 | #include <linux/sched.h> | |
15 | #include <linux/kernel.h> | |
16 | #include <linux/signal.h> | |
17 | #include <linux/errno.h> | |
18 | #include <linux/wait.h> | |
19 | #include <linux/ptrace.h> | |
e35a8925 | 20 | #include <linux/tracehook.h> |
1da177e4 LT |
21 | #include <linux/unistd.h> |
22 | #include <linux/mm.h> | |
23 | #include <linux/tty.h> | |
1da177e4 LT |
24 | #include <linux/binfmts.h> |
25 | #include <linux/bitops.h> | |
812cb83a | 26 | #include <linux/context_tracking.h> |
1da177e4 LT |
27 | |
28 | #include <asm/uaccess.h> | |
29 | #include <asm/ptrace.h> | |
1da177e4 LT |
30 | #include <asm/pgtable.h> |
31 | #include <asm/fpumacro.h> | |
32 | #include <asm/uctx.h> | |
33 | #include <asm/siginfo.h> | |
34 | #include <asm/visasm.h> | |
d550bbd4 DH |
35 | #include <asm/switch_to.h> |
36 | #include <asm/cacheflush.h> | |
1da177e4 | 37 | |
5598473a | 38 | #include "sigutil.h" |
abaff455 SR |
39 | #include "systbls.h" |
40 | #include "kernel.h" | |
41 | #include "entry.h" | |
062ea6d3 | 42 | |
1da177e4 LT |
43 | /* {set, get}context() needed for 64-bit SparcLinux userland. */ |
44 | asmlinkage void sparc64_set_context(struct pt_regs *regs) | |
45 | { | |
46 | struct ucontext __user *ucp = (struct ucontext __user *) | |
47 | regs->u_regs[UREG_I0]; | |
812cb83a | 48 | enum ctx_state prev_state = exception_enter(); |
1da177e4 LT |
49 | mc_gregset_t __user *grp; |
50 | unsigned long pc, npc, tstate; | |
51 | unsigned long fp, i7; | |
52 | unsigned char fenab; | |
53 | int err; | |
54 | ||
397d1533 | 55 | synchronize_user_stack(); |
1da177e4 LT |
56 | if (get_thread_wsaved() || |
57 | (((unsigned long)ucp) & (sizeof(unsigned long)-1)) || | |
58 | (!__access_ok(ucp, sizeof(*ucp)))) | |
59 | goto do_sigsegv; | |
60 | grp = &ucp->uc_mcontext.mc_gregs; | |
61 | err = __get_user(pc, &((*grp)[MC_PC])); | |
62 | err |= __get_user(npc, &((*grp)[MC_NPC])); | |
63 | if (err || ((pc | npc) & 3)) | |
64 | goto do_sigsegv; | |
65 | if (regs->u_regs[UREG_I1]) { | |
66 | sigset_t set; | |
67 | ||
68 | if (_NSIG_WORDS == 1) { | |
69 | if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0])) | |
70 | goto do_sigsegv; | |
71 | } else { | |
72 | if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t))) | |
73 | goto do_sigsegv; | |
74 | } | |
faddf598 | 75 | set_current_blocked(&set); |
1da177e4 LT |
76 | } |
77 | if (test_thread_flag(TIF_32BIT)) { | |
78 | pc &= 0xffffffff; | |
79 | npc &= 0xffffffff; | |
80 | } | |
81 | regs->tpc = pc; | |
82 | regs->tnpc = npc; | |
83 | err |= __get_user(regs->y, &((*grp)[MC_Y])); | |
84 | err |= __get_user(tstate, &((*grp)[MC_TSTATE])); | |
85 | regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC); | |
86 | regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC)); | |
87 | err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1])); | |
88 | err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2])); | |
89 | err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3])); | |
90 | err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4])); | |
91 | err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5])); | |
92 | err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6])); | |
0a4949c4 DM |
93 | |
94 | /* Skip %g7 as that's the thread register in userspace. */ | |
95 | ||
1da177e4 LT |
96 | err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0])); |
97 | err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1])); | |
98 | err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2])); | |
99 | err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3])); | |
100 | err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4])); | |
101 | err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5])); | |
102 | err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6])); | |
103 | err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7])); | |
104 | ||
105 | err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp)); | |
106 | err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7)); | |
107 | err |= __put_user(fp, | |
108 | (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6]))); | |
109 | err |= __put_user(i7, | |
110 | (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7]))); | |
111 | ||
112 | err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab)); | |
113 | if (fenab) { | |
114 | unsigned long *fpregs = current_thread_info()->fpregs; | |
115 | unsigned long fprs; | |
116 | ||
117 | fprs_write(0); | |
118 | err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs)); | |
119 | if (fprs & FPRS_DL) | |
120 | err |= copy_from_user(fpregs, | |
121 | &(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs), | |
122 | (sizeof(unsigned int) * 32)); | |
123 | if (fprs & FPRS_DU) | |
124 | err |= copy_from_user(fpregs+16, | |
125 | ((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16, | |
126 | (sizeof(unsigned int) * 32)); | |
127 | err |= __get_user(current_thread_info()->xfsr[0], | |
128 | &(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr)); | |
129 | err |= __get_user(current_thread_info()->gsr[0], | |
130 | &(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr)); | |
131 | regs->tstate &= ~TSTATE_PEF; | |
132 | } | |
133 | if (err) | |
134 | goto do_sigsegv; | |
812cb83a KT |
135 | out: |
136 | exception_exit(prev_state); | |
1da177e4 LT |
137 | return; |
138 | do_sigsegv: | |
139 | force_sig(SIGSEGV, current); | |
812cb83a | 140 | goto out; |
1da177e4 LT |
141 | } |
142 | ||
143 | asmlinkage void sparc64_get_context(struct pt_regs *regs) | |
144 | { | |
145 | struct ucontext __user *ucp = (struct ucontext __user *) | |
146 | regs->u_regs[UREG_I0]; | |
812cb83a | 147 | enum ctx_state prev_state = exception_enter(); |
1da177e4 LT |
148 | mc_gregset_t __user *grp; |
149 | mcontext_t __user *mcp; | |
150 | unsigned long fp, i7; | |
151 | unsigned char fenab; | |
152 | int err; | |
153 | ||
154 | synchronize_user_stack(); | |
155 | if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp))) | |
156 | goto do_sigsegv; | |
157 | ||
158 | #if 1 | |
159 | fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */ | |
160 | #else | |
161 | fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF); | |
162 | #endif | |
163 | ||
164 | mcp = &ucp->uc_mcontext; | |
165 | grp = &mcp->mc_gregs; | |
166 | ||
167 | /* Skip over the trap instruction, first. */ | |
168 | if (test_thread_flag(TIF_32BIT)) { | |
169 | regs->tpc = (regs->tnpc & 0xffffffff); | |
170 | regs->tnpc = (regs->tnpc + 4) & 0xffffffff; | |
171 | } else { | |
172 | regs->tpc = regs->tnpc; | |
173 | regs->tnpc += 4; | |
174 | } | |
175 | err = 0; | |
176 | if (_NSIG_WORDS == 1) | |
177 | err |= __put_user(current->blocked.sig[0], | |
178 | (unsigned long __user *)&ucp->uc_sigmask); | |
179 | else | |
180 | err |= __copy_to_user(&ucp->uc_sigmask, ¤t->blocked, | |
181 | sizeof(sigset_t)); | |
182 | ||
183 | err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE])); | |
184 | err |= __put_user(regs->tpc, &((*grp)[MC_PC])); | |
185 | err |= __put_user(regs->tnpc, &((*grp)[MC_NPC])); | |
186 | err |= __put_user(regs->y, &((*grp)[MC_Y])); | |
187 | err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1])); | |
188 | err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2])); | |
189 | err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3])); | |
190 | err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4])); | |
191 | err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5])); | |
192 | err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6])); | |
193 | err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7])); | |
194 | err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0])); | |
195 | err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1])); | |
196 | err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2])); | |
197 | err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3])); | |
198 | err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4])); | |
199 | err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5])); | |
200 | err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6])); | |
201 | err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7])); | |
202 | ||
203 | err |= __get_user(fp, | |
204 | (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6]))); | |
205 | err |= __get_user(i7, | |
206 | (&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7]))); | |
207 | err |= __put_user(fp, &(mcp->mc_fp)); | |
208 | err |= __put_user(i7, &(mcp->mc_i7)); | |
209 | ||
210 | err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab)); | |
211 | if (fenab) { | |
212 | unsigned long *fpregs = current_thread_info()->fpregs; | |
213 | unsigned long fprs; | |
214 | ||
215 | fprs = current_thread_info()->fpsaved[0]; | |
216 | if (fprs & FPRS_DL) | |
217 | err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs, | |
218 | (sizeof(unsigned int) * 32)); | |
219 | if (fprs & FPRS_DU) | |
220 | err |= copy_to_user( | |
221 | ((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16, | |
222 | (sizeof(unsigned int) * 32)); | |
223 | err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr)); | |
224 | err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr)); | |
225 | err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs)); | |
226 | } | |
227 | if (err) | |
228 | goto do_sigsegv; | |
812cb83a KT |
229 | out: |
230 | exception_exit(prev_state); | |
1da177e4 LT |
231 | return; |
232 | do_sigsegv: | |
233 | force_sig(SIGSEGV, current); | |
812cb83a | 234 | goto out; |
1da177e4 LT |
235 | } |
236 | ||
237 | struct rt_signal_frame { | |
238 | struct sparc_stackf ss; | |
239 | siginfo_t info; | |
240 | struct pt_regs regs; | |
241 | __siginfo_fpu_t __user *fpu_save; | |
242 | stack_t stack; | |
243 | sigset_t mask; | |
5598473a | 244 | __siginfo_rwin_t *rwin_save; |
1da177e4 LT |
245 | }; |
246 | ||
1da177e4 LT |
247 | void do_rt_sigreturn(struct pt_regs *regs) |
248 | { | |
249 | struct rt_signal_frame __user *sf; | |
250 | unsigned long tpc, tnpc, tstate; | |
251 | __siginfo_fpu_t __user *fpu_save; | |
5598473a | 252 | __siginfo_rwin_t __user *rwin_save; |
1da177e4 | 253 | sigset_t set; |
1da177e4 LT |
254 | int err; |
255 | ||
256 | /* Always make any pending restarted system calls return -EINTR */ | |
f56141e3 | 257 | current->restart_block.fn = do_no_restart_syscall; |
1da177e4 LT |
258 | |
259 | synchronize_user_stack (); | |
260 | sf = (struct rt_signal_frame __user *) | |
261 | (regs->u_regs [UREG_FP] + STACK_BIAS); | |
262 | ||
263 | /* 1. Make sure we are not getting garbage from the user */ | |
264 | if (((unsigned long) sf) & 3) | |
265 | goto segv; | |
266 | ||
267 | err = get_user(tpc, &sf->regs.tpc); | |
268 | err |= __get_user(tnpc, &sf->regs.tnpc); | |
269 | if (test_thread_flag(TIF_32BIT)) { | |
270 | tpc &= 0xffffffff; | |
271 | tnpc &= 0xffffffff; | |
272 | } | |
273 | err |= ((tpc | tnpc) & 3); | |
274 | ||
275 | /* 2. Restore the state */ | |
276 | err |= __get_user(regs->y, &sf->regs.y); | |
277 | err |= __get_user(tstate, &sf->regs.tstate); | |
278 | err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs)); | |
279 | ||
280 | /* User can only change condition codes and %asi in %tstate. */ | |
281 | regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC); | |
282 | regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC)); | |
283 | ||
284 | err |= __get_user(fpu_save, &sf->fpu_save); | |
5598473a DM |
285 | if (!err && fpu_save) |
286 | err |= restore_fpu_state(regs, fpu_save); | |
1da177e4 LT |
287 | |
288 | err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t)); | |
99b06feb AV |
289 | err |= restore_altstack(&sf->stack); |
290 | if (err) | |
1da177e4 | 291 | goto segv; |
62715ec8 | 292 | |
5598473a DM |
293 | err |= __get_user(rwin_save, &sf->rwin_save); |
294 | if (!err && rwin_save) { | |
295 | if (restore_rwin_state(rwin_save)) | |
296 | goto segv; | |
297 | } | |
298 | ||
1da177e4 LT |
299 | regs->tpc = tpc; |
300 | regs->tnpc = tnpc; | |
1da177e4 | 301 | |
2678fefe | 302 | /* Prevent syscall restart. */ |
28e61036 | 303 | pt_regs_clear_syscall(regs); |
2678fefe | 304 | |
faddf598 | 305 | set_current_blocked(&set); |
1da177e4 LT |
306 | return; |
307 | segv: | |
308 | force_sig(SIGSEGV, current); | |
309 | } | |
310 | ||
311 | /* Checks if the fp is valid */ | |
5598473a | 312 | static int invalid_frame_pointer(void __user *fp) |
1da177e4 | 313 | { |
f036d9f3 | 314 | if (((unsigned long) fp) & 15) |
1da177e4 LT |
315 | return 1; |
316 | return 0; | |
317 | } | |
318 | ||
08f73957 | 319 | static inline void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize) |
1da177e4 | 320 | { |
dc5dc7e6 | 321 | unsigned long sp = regs->u_regs[UREG_FP] + STACK_BIAS; |
1da177e4 | 322 | |
dc5dc7e6 DM |
323 | /* |
324 | * If we are on the alternate signal stack and would overflow it, don't. | |
325 | * Return an always-bogus address instead so we will die with SIGSEGV. | |
326 | */ | |
327 | if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize))) | |
328 | return (void __user *) -1L; | |
1da177e4 LT |
329 | |
330 | /* This is the X/Open sanctioned signal stack switching. */ | |
08f73957 | 331 | sp = sigsp(sp, ksig) - framesize; |
f036d9f3 | 332 | |
dc5dc7e6 DM |
333 | /* Always align the stack frame. This handles two cases. First, |
334 | * sigaltstack need not be mindful of platform specific stack | |
335 | * alignment. Second, if we took this signal because the stack | |
336 | * is not aligned properly, we'd like to take the signal cleanly | |
337 | * and report that. | |
338 | */ | |
f036d9f3 | 339 | sp &= ~15UL; |
dc5dc7e6 | 340 | |
f036d9f3 | 341 | return (void __user *) sp; |
1da177e4 LT |
342 | } |
343 | ||
392c2180 | 344 | static inline int |
08f73957 | 345 | setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) |
1da177e4 LT |
346 | { |
347 | struct rt_signal_frame __user *sf; | |
5598473a DM |
348 | int wsaved, err, sf_size; |
349 | void __user *tail; | |
1da177e4 LT |
350 | |
351 | /* 1. Make sure everything is clean */ | |
352 | synchronize_user_stack(); | |
353 | save_and_clear_fpu(); | |
354 | ||
5598473a | 355 | wsaved = get_thread_wsaved(); |
1da177e4 | 356 | |
5598473a DM |
357 | sf_size = sizeof(struct rt_signal_frame); |
358 | if (current_thread_info()->fpsaved[0] & FPRS_FEF) | |
359 | sf_size += sizeof(__siginfo_fpu_t); | |
360 | if (wsaved) | |
361 | sf_size += sizeof(__siginfo_rwin_t); | |
1da177e4 | 362 | sf = (struct rt_signal_frame __user *) |
08f73957 | 363 | get_sigframe(ksig, regs, sf_size); |
1da177e4 | 364 | |
08f73957 AV |
365 | if (invalid_frame_pointer (sf)) { |
366 | do_exit(SIGILL); /* won't return, actually */ | |
367 | return -EINVAL; | |
368 | } | |
1da177e4 | 369 | |
5598473a DM |
370 | tail = (sf + 1); |
371 | ||
1da177e4 LT |
372 | /* 2. Save the current process state */ |
373 | err = copy_to_user(&sf->regs, regs, sizeof (*regs)); | |
374 | ||
375 | if (current_thread_info()->fpsaved[0] & FPRS_FEF) { | |
5598473a DM |
376 | __siginfo_fpu_t __user *fpu_save = tail; |
377 | tail += sizeof(__siginfo_fpu_t); | |
378 | err |= save_fpu_state(regs, fpu_save); | |
379 | err |= __put_user((u64)fpu_save, &sf->fpu_save); | |
1da177e4 LT |
380 | } else { |
381 | err |= __put_user(0, &sf->fpu_save); | |
382 | } | |
5598473a DM |
383 | if (wsaved) { |
384 | __siginfo_rwin_t __user *rwin_save = tail; | |
385 | tail += sizeof(__siginfo_rwin_t); | |
386 | err |= save_rwin_state(wsaved, rwin_save); | |
387 | err |= __put_user((u64)rwin_save, &sf->rwin_save); | |
388 | set_thread_wsaved(0); | |
389 | } else { | |
390 | err |= __put_user(0, &sf->rwin_save); | |
391 | } | |
1da177e4 LT |
392 | |
393 | /* Setup sigaltstack */ | |
99b06feb | 394 | err |= __save_altstack(&sf->stack, regs->u_regs[UREG_FP]); |
1da177e4 | 395 | |
08f73957 | 396 | err |= copy_to_user(&sf->mask, sigmask_to_save(), sizeof(sigset_t)); |
1da177e4 | 397 | |
5598473a DM |
398 | if (!wsaved) { |
399 | err |= copy_in_user((u64 __user *)sf, | |
400 | (u64 __user *)(regs->u_regs[UREG_FP] + | |
401 | STACK_BIAS), | |
402 | sizeof(struct reg_window)); | |
403 | } else { | |
404 | struct reg_window *rp; | |
1da177e4 | 405 | |
5598473a DM |
406 | rp = ¤t_thread_info()->reg_window[wsaved - 1]; |
407 | err |= copy_to_user(sf, rp, sizeof(struct reg_window)); | |
408 | } | |
08f73957 AV |
409 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) |
410 | err |= copy_siginfo_to_user(&sf->info, &ksig->info); | |
1da177e4 | 411 | else { |
08f73957 | 412 | err |= __put_user(ksig->sig, &sf->info.si_signo); |
1da177e4 LT |
413 | err |= __put_user(SI_NOINFO, &sf->info.si_code); |
414 | } | |
415 | if (err) | |
08f73957 | 416 | return err; |
1da177e4 LT |
417 | |
418 | /* 3. signal handler back-trampoline and parameters */ | |
419 | regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS; | |
08f73957 | 420 | regs->u_regs[UREG_I0] = ksig->sig; |
1da177e4 LT |
421 | regs->u_regs[UREG_I1] = (unsigned long) &sf->info; |
422 | ||
423 | /* The sigcontext is passed in this way because of how it | |
424 | * is defined in GLIBC's /usr/include/bits/sigcontext.h | |
425 | * for sparc64. It includes the 128 bytes of siginfo_t. | |
426 | */ | |
427 | regs->u_regs[UREG_I2] = (unsigned long) &sf->info; | |
428 | ||
429 | /* 5. signal handler */ | |
08f73957 | 430 | regs->tpc = (unsigned long) ksig->ka.sa.sa_handler; |
1da177e4 LT |
431 | regs->tnpc = (regs->tpc + 4); |
432 | if (test_thread_flag(TIF_32BIT)) { | |
433 | regs->tpc &= 0xffffffff; | |
434 | regs->tnpc &= 0xffffffff; | |
435 | } | |
436 | /* 4. return to kernel instructions */ | |
08f73957 | 437 | regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer; |
392c2180 | 438 | return 0; |
1da177e4 LT |
439 | } |
440 | ||
441 | static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs, | |
28e61036 | 442 | struct sigaction *sa) |
1da177e4 LT |
443 | { |
444 | switch (regs->u_regs[UREG_I0]) { | |
445 | case ERESTART_RESTARTBLOCK: | |
446 | case ERESTARTNOHAND: | |
447 | no_system_call_restart: | |
448 | regs->u_regs[UREG_I0] = EINTR; | |
449 | regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY); | |
450 | break; | |
451 | case ERESTARTSYS: | |
452 | if (!(sa->sa_flags & SA_RESTART)) | |
453 | goto no_system_call_restart; | |
454 | /* fallthrough */ | |
455 | case ERESTARTNOINTR: | |
456 | regs->u_regs[UREG_I0] = orig_i0; | |
457 | regs->tpc -= 4; | |
458 | regs->tnpc -= 4; | |
459 | } | |
460 | } | |
461 | ||
462 | /* Note that 'init' is a special process: it doesn't get signals it doesn't | |
463 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
464 | * mistake. | |
465 | */ | |
238468b2 | 466 | static void do_signal(struct pt_regs *regs, unsigned long orig_i0) |
1da177e4 | 467 | { |
08f73957 | 468 | struct ksignal ksig; |
28e61036 | 469 | int restart_syscall; |
08f73957 | 470 | bool has_handler; |
1da177e4 | 471 | |
1d299bc7 DM |
472 | /* It's a lot of work and synchronization to add a new ptrace |
473 | * register for GDB to save and restore in order to get | |
474 | * orig_i0 correct for syscall restarts when debugging. | |
475 | * | |
e88d2468 DM |
476 | * Although it should be the case that most of the global |
477 | * registers are volatile across a system call, glibc already | |
478 | * depends upon that fact that we preserve them. So we can't | |
479 | * just use any global register to save away the orig_i0 value. | |
480 | * | |
481 | * In particular %g2, %g3, %g4, and %g5 are all assumed to be | |
482 | * preserved across a system call trap by various pieces of | |
483 | * code in glibc. | |
484 | * | |
485 | * %g7 is used as the "thread register". %g6 is not used in | |
486 | * any fixed manner. %g6 is used as a scratch register and | |
487 | * a compiler temporary, but it's value is never used across | |
488 | * a system call. Therefore %g6 is usable for orig_i0 storage. | |
1d299bc7 | 489 | */ |
2678fefe | 490 | if (pt_regs_is_syscall(regs) && |
1d299bc7 | 491 | (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) |
e88d2468 | 492 | regs->u_regs[UREG_G6] = orig_i0; |
1da177e4 | 493 | |
09337f50 | 494 | #ifdef CONFIG_COMPAT |
1da177e4 | 495 | if (test_thread_flag(TIF_32BIT)) { |
08f73957 | 496 | do_signal32(regs); |
2d7d5f05 | 497 | return; |
1da177e4 LT |
498 | } |
499 | #endif | |
500 | ||
08f73957 | 501 | has_handler = get_signal(&ksig); |
28e61036 | 502 | |
1d299bc7 DM |
503 | restart_syscall = 0; |
504 | if (pt_regs_is_syscall(regs) && | |
505 | (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) { | |
506 | restart_syscall = 1; | |
e88d2468 | 507 | orig_i0 = regs->u_regs[UREG_G6]; |
1d299bc7 | 508 | } |
28e61036 | 509 | |
08f73957 | 510 | if (has_handler) { |
28e61036 | 511 | if (restart_syscall) |
08f73957 AV |
512 | syscall_restart(orig_i0, regs, &ksig.ka.sa); |
513 | signal_setup_done(setup_rt_frame(&ksig, regs), &ksig, 0); | |
514 | } else { | |
515 | if (restart_syscall) { | |
516 | switch (regs->u_regs[UREG_I0]) { | |
517 | case ERESTARTNOHAND: | |
518 | case ERESTARTSYS: | |
519 | case ERESTARTNOINTR: | |
520 | /* replay the system call when we are done */ | |
521 | regs->u_regs[UREG_I0] = orig_i0; | |
522 | regs->tpc -= 4; | |
523 | regs->tnpc -= 4; | |
524 | pt_regs_clear_syscall(regs); | |
525 | case ERESTART_RESTARTBLOCK: | |
526 | regs->u_regs[UREG_G1] = __NR_restart_syscall; | |
527 | regs->tpc -= 4; | |
528 | regs->tnpc -= 4; | |
529 | pt_regs_clear_syscall(regs); | |
530 | } | |
531 | } | |
532 | restore_saved_sigmask(); | |
1da177e4 | 533 | } |
1da177e4 LT |
534 | } |
535 | ||
7697daaa | 536 | void do_notify_resume(struct pt_regs *regs, unsigned long orig_i0, unsigned long thread_info_flags) |
1da177e4 | 537 | { |
812cb83a | 538 | user_exit(); |
9a28dbf8 | 539 | if (thread_info_flags & _TIF_SIGPENDING) |
238468b2 | 540 | do_signal(regs, orig_i0); |
e35a8925 RM |
541 | if (thread_info_flags & _TIF_NOTIFY_RESUME) { |
542 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
543 | tracehook_notify_resume(regs); | |
544 | } | |
812cb83a | 545 | user_enter(); |
1da177e4 | 546 | } |
ee18d64c | 547 |