Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
a53c8fab | 2 | * Copyright IBM Corp. 1999, 2006 |
1da177e4 LT |
3 | * Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com) |
4 | * | |
5 | * Based on Intel version | |
6 | * | |
7 | * Copyright (C) 1991, 1992 Linus Torvalds | |
8 | * | |
9 | * 1997-11-28 Modified for POSIX.1b signals by Richard Henderson | |
10 | */ | |
11 | ||
1da177e4 LT |
12 | #include <linux/sched.h> |
13 | #include <linux/mm.h> | |
14 | #include <linux/smp.h> | |
1da177e4 LT |
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> | |
20 | #include <linux/unistd.h> | |
21 | #include <linux/stddef.h> | |
22 | #include <linux/tty.h> | |
23 | #include <linux/personality.h> | |
24 | #include <linux/binfmts.h> | |
753c4dd6 | 25 | #include <linux/tracehook.h> |
26689452 | 26 | #include <linux/syscalls.h> |
7757591a | 27 | #include <linux/compat.h> |
1da177e4 LT |
28 | #include <asm/ucontext.h> |
29 | #include <asm/uaccess.h> | |
30 | #include <asm/lowcore.h> | |
a0616cde | 31 | #include <asm/switch_to.h> |
a806170e | 32 | #include "entry.h" |
1da177e4 | 33 | |
80703617 MS |
34 | /* |
35 | * Layout of an old-style signal-frame: | |
36 | * ----------------------------------------- | |
37 | * | save area (_SIGNAL_FRAMESIZE) | | |
38 | * ----------------------------------------- | |
39 | * | struct sigcontext | | |
40 | * | oldmask | | |
41 | * | _sigregs * | | |
42 | * ----------------------------------------- | |
43 | * | _sigregs with | | |
44 | * | _s390_regs_common | | |
45 | * | _s390_fp_regs | | |
46 | * ----------------------------------------- | |
47 | * | int signo | | |
48 | * ----------------------------------------- | |
49 | * | _sigregs_ext with | | |
50 | * | gprs_high 64 byte (opt) | | |
51 | * | vxrs_low 128 byte (opt) | | |
52 | * | vxrs_high 256 byte (opt) | | |
53 | * | reserved 128 byte (opt) | | |
54 | * ----------------------------------------- | |
55 | * | __u16 svc_insn | | |
56 | * ----------------------------------------- | |
57 | * The svc_insn entry with the sigreturn system call opcode does not | |
58 | * have a fixed position and moves if gprs_high or vxrs exist. | |
59 | * Future extensions will be added to _sigregs_ext. | |
60 | */ | |
61 | struct sigframe | |
1da177e4 LT |
62 | { |
63 | __u8 callee_used_stack[__SIGNAL_FRAMESIZE]; | |
64 | struct sigcontext sc; | |
65 | _sigregs sregs; | |
66 | int signo; | |
80703617 MS |
67 | _sigregs_ext sregs_ext; |
68 | __u16 svc_insn; /* Offset of svc_insn is NOT fixed! */ | |
69 | }; | |
1da177e4 | 70 | |
80703617 MS |
71 | /* |
72 | * Layout of an rt signal-frame: | |
73 | * ----------------------------------------- | |
74 | * | save area (_SIGNAL_FRAMESIZE) | | |
75 | * ----------------------------------------- | |
76 | * | svc __NR_rt_sigreturn 2 byte | | |
77 | * ----------------------------------------- | |
78 | * | struct siginfo | | |
79 | * ----------------------------------------- | |
80 | * | struct ucontext_extended with | | |
81 | * | unsigned long uc_flags | | |
82 | * | struct ucontext *uc_link | | |
83 | * | stack_t uc_stack | | |
84 | * | _sigregs uc_mcontext with | | |
85 | * | _s390_regs_common | | |
86 | * | _s390_fp_regs | | |
87 | * | sigset_t uc_sigmask | | |
88 | * | _sigregs_ext uc_mcontext_ext | | |
89 | * | gprs_high 64 byte (opt) | | |
90 | * | vxrs_low 128 byte (opt) | | |
91 | * | vxrs_high 256 byte (opt)| | |
92 | * | reserved 128 byte (opt) | | |
93 | * ----------------------------------------- | |
94 | * Future extensions will be added to _sigregs_ext. | |
95 | */ | |
96 | struct rt_sigframe | |
1da177e4 LT |
97 | { |
98 | __u8 callee_used_stack[__SIGNAL_FRAMESIZE]; | |
80703617 | 99 | __u16 svc_insn; |
1da177e4 | 100 | struct siginfo info; |
80703617 MS |
101 | struct ucontext_extended uc; |
102 | }; | |
103 | ||
104 | /* Store registers needed to create the signal frame */ | |
105 | static void store_sigregs(void) | |
106 | { | |
107 | save_access_regs(current->thread.acrs); | |
d0164ee2 | 108 | save_fpu_regs(); |
80703617 MS |
109 | } |
110 | ||
111 | /* Load registers after signal return */ | |
112 | static void load_sigregs(void) | |
113 | { | |
114 | restore_access_regs(current->thread.acrs); | |
80703617 | 115 | } |
1da177e4 | 116 | |
1da177e4 LT |
117 | /* Returns non-zero on fault. */ |
118 | static int save_sigregs(struct pt_regs *regs, _sigregs __user *sregs) | |
119 | { | |
6837a8c3 GS |
120 | _sigregs user_sregs; |
121 | ||
1da177e4 LT |
122 | /* Copy a 'clean' PSW mask to the user to avoid leaking |
123 | information about whether PER is currently on. */ | |
e258d719 | 124 | user_sregs.regs.psw.mask = PSW_USER_BITS | |
5ebf250d | 125 | (regs->psw.mask & (PSW_MASK_USER | PSW_MASK_RI)); |
b05e3703 MS |
126 | user_sregs.regs.psw.addr = regs->psw.addr; |
127 | memcpy(&user_sregs.regs.gprs, ®s->gprs, sizeof(sregs->regs.gprs)); | |
6837a8c3 | 128 | memcpy(&user_sregs.regs.acrs, current->thread.acrs, |
4725c860 | 129 | sizeof(user_sregs.regs.acrs)); |
904818e2 | 130 | fpregs_store(&user_sregs.fpregs, ¤t->thread.fpu); |
f8544ec4 HC |
131 | if (__copy_to_user(sregs, &user_sregs, sizeof(_sigregs))) |
132 | return -EFAULT; | |
133 | return 0; | |
1da177e4 LT |
134 | } |
135 | ||
1da177e4 LT |
136 | static int restore_sigregs(struct pt_regs *regs, _sigregs __user *sregs) |
137 | { | |
6837a8c3 | 138 | _sigregs user_sregs; |
1da177e4 LT |
139 | |
140 | /* Alwys make any pending restarted system call return -EINTR */ | |
f56141e3 | 141 | current->restart_block.fn = do_no_restart_syscall; |
1da177e4 | 142 | |
4725c860 | 143 | if (__copy_from_user(&user_sregs, sregs, sizeof(user_sregs))) |
f8544ec4 | 144 | return -EFAULT; |
4725c860 | 145 | |
5ebf250d HC |
146 | if (!is_ri_task(current) && (user_sregs.regs.psw.mask & PSW_MASK_RI)) |
147 | return -EINVAL; | |
148 | ||
4084eb77 HB |
149 | /* Test the floating-point-control word. */ |
150 | if (test_fp_ctl(user_sregs.fpregs.fpc)) | |
4725c860 MS |
151 | return -EINVAL; |
152 | ||
e258d719 | 153 | /* Use regs->psw.mask instead of PSW_USER_BITS to preserve PER bit. */ |
aa7e04b3 | 154 | regs->psw.mask = (regs->psw.mask & ~(PSW_MASK_USER | PSW_MASK_RI)) | |
5ebf250d | 155 | (user_sregs.regs.psw.mask & (PSW_MASK_USER | PSW_MASK_RI)); |
fa968ee2 | 156 | /* Check for invalid user address space control. */ |
e258d719 MS |
157 | if ((regs->psw.mask & PSW_MASK_ASC) == PSW_ASC_HOME) |
158 | regs->psw.mask = PSW_ASC_PRIMARY | | |
fa968ee2 | 159 | (regs->psw.mask & ~PSW_MASK_ASC); |
d4e81b35 MS |
160 | /* Check for invalid amode */ |
161 | if (regs->psw.mask & PSW_MASK_EA) | |
162 | regs->psw.mask |= PSW_MASK_BA; | |
163 | regs->psw.addr = user_sregs.regs.psw.addr; | |
b05e3703 | 164 | memcpy(®s->gprs, &user_sregs.regs.gprs, sizeof(sregs->regs.gprs)); |
6837a8c3 | 165 | memcpy(¤t->thread.acrs, &user_sregs.regs.acrs, |
4725c860 | 166 | sizeof(current->thread.acrs)); |
1da177e4 | 167 | |
904818e2 | 168 | fpregs_load(&user_sregs.fpregs, ¤t->thread.fpu); |
1da177e4 | 169 | |
d3a73acb | 170 | clear_pt_regs_flag(regs, PIF_SYSCALL); /* No longer in a system call */ |
1da177e4 LT |
171 | return 0; |
172 | } | |
173 | ||
80703617 MS |
174 | /* Returns non-zero on fault. */ |
175 | static int save_sigregs_ext(struct pt_regs *regs, | |
176 | _sigregs_ext __user *sregs_ext) | |
177 | { | |
80703617 MS |
178 | __u64 vxrs[__NUM_VXRS_LOW]; |
179 | int i; | |
180 | ||
181 | /* Save vector registers to signal stack */ | |
b5510d9b | 182 | if (MACHINE_HAS_VX) { |
80703617 | 183 | for (i = 0; i < __NUM_VXRS_LOW; i++) |
904818e2 | 184 | vxrs[i] = *((__u64 *)(current->thread.fpu.vxrs + i) + 1); |
80703617 MS |
185 | if (__copy_to_user(&sregs_ext->vxrs_low, vxrs, |
186 | sizeof(sregs_ext->vxrs_low)) || | |
187 | __copy_to_user(&sregs_ext->vxrs_high, | |
904818e2 | 188 | current->thread.fpu.vxrs + __NUM_VXRS_LOW, |
80703617 MS |
189 | sizeof(sregs_ext->vxrs_high))) |
190 | return -EFAULT; | |
191 | } | |
80703617 MS |
192 | return 0; |
193 | } | |
194 | ||
195 | static int restore_sigregs_ext(struct pt_regs *regs, | |
196 | _sigregs_ext __user *sregs_ext) | |
197 | { | |
80703617 MS |
198 | __u64 vxrs[__NUM_VXRS_LOW]; |
199 | int i; | |
200 | ||
201 | /* Restore vector registers from signal stack */ | |
b5510d9b | 202 | if (MACHINE_HAS_VX) { |
80703617 MS |
203 | if (__copy_from_user(vxrs, &sregs_ext->vxrs_low, |
204 | sizeof(sregs_ext->vxrs_low)) || | |
904818e2 | 205 | __copy_from_user(current->thread.fpu.vxrs + __NUM_VXRS_LOW, |
80703617 MS |
206 | &sregs_ext->vxrs_high, |
207 | sizeof(sregs_ext->vxrs_high))) | |
208 | return -EFAULT; | |
209 | for (i = 0; i < __NUM_VXRS_LOW; i++) | |
904818e2 | 210 | *((__u64 *)(current->thread.fpu.vxrs + i) + 1) = vxrs[i]; |
80703617 | 211 | } |
80703617 MS |
212 | return 0; |
213 | } | |
214 | ||
26689452 | 215 | SYSCALL_DEFINE0(sigreturn) |
1da177e4 | 216 | { |
03ff9a23 | 217 | struct pt_regs *regs = task_pt_regs(current); |
80703617 MS |
218 | struct sigframe __user *frame = |
219 | (struct sigframe __user *) regs->gprs[15]; | |
1da177e4 LT |
220 | sigset_t set; |
221 | ||
1da177e4 LT |
222 | if (__copy_from_user(&set.sig, &frame->sc.oldmask, _SIGMASK_COPY_SIZE)) |
223 | goto badframe; | |
391c62fe | 224 | set_current_blocked(&set); |
d0164ee2 | 225 | save_fpu_regs(); |
1da177e4 LT |
226 | if (restore_sigregs(regs, &frame->sregs)) |
227 | goto badframe; | |
80703617 MS |
228 | if (restore_sigregs_ext(regs, &frame->sregs_ext)) |
229 | goto badframe; | |
230 | load_sigregs(); | |
1da177e4 | 231 | return regs->gprs[2]; |
1da177e4 LT |
232 | badframe: |
233 | force_sig(SIGSEGV, current); | |
234 | return 0; | |
235 | } | |
236 | ||
26689452 | 237 | SYSCALL_DEFINE0(rt_sigreturn) |
1da177e4 | 238 | { |
03ff9a23 | 239 | struct pt_regs *regs = task_pt_regs(current); |
80703617 MS |
240 | struct rt_sigframe __user *frame = |
241 | (struct rt_sigframe __user *)regs->gprs[15]; | |
1da177e4 LT |
242 | sigset_t set; |
243 | ||
1da177e4 LT |
244 | if (__copy_from_user(&set.sig, &frame->uc.uc_sigmask, sizeof(set))) |
245 | goto badframe; | |
391c62fe | 246 | set_current_blocked(&set); |
80703617 MS |
247 | if (restore_altstack(&frame->uc.uc_stack)) |
248 | goto badframe; | |
d0164ee2 | 249 | save_fpu_regs(); |
1da177e4 LT |
250 | if (restore_sigregs(regs, &frame->uc.uc_mcontext)) |
251 | goto badframe; | |
80703617 | 252 | if (restore_sigregs_ext(regs, &frame->uc.uc_mcontext_ext)) |
4e3df37e | 253 | goto badframe; |
80703617 | 254 | load_sigregs(); |
1da177e4 | 255 | return regs->gprs[2]; |
1da177e4 LT |
256 | badframe: |
257 | force_sig(SIGSEGV, current); | |
258 | return 0; | |
259 | } | |
260 | ||
1da177e4 LT |
261 | /* |
262 | * Determine which stack to use.. | |
263 | */ | |
264 | static inline void __user * | |
265 | get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size) | |
266 | { | |
267 | unsigned long sp; | |
268 | ||
269 | /* Default to using normal stack */ | |
270 | sp = regs->gprs[15]; | |
271 | ||
de553438 HC |
272 | /* Overflow on alternate signal stack gives SIGSEGV. */ |
273 | if (on_sig_stack(sp) && !on_sig_stack((sp - frame_size) & -8UL)) | |
274 | return (void __user *) -1UL; | |
275 | ||
1da177e4 LT |
276 | /* This is the X/Open sanctioned signal stack switching. */ |
277 | if (ka->sa.sa_flags & SA_ONSTACK) { | |
278 | if (! sas_ss_flags(sp)) | |
279 | sp = current->sas_ss_sp + current->sas_ss_size; | |
280 | } | |
281 | ||
1da177e4 LT |
282 | return (void __user *)((sp - frame_size) & -8ul); |
283 | } | |
284 | ||
54dfe5dd HC |
285 | static int setup_frame(int sig, struct k_sigaction *ka, |
286 | sigset_t *set, struct pt_regs * regs) | |
1da177e4 | 287 | { |
80703617 MS |
288 | struct sigframe __user *frame; |
289 | struct sigcontext sc; | |
290 | unsigned long restorer; | |
291 | size_t frame_size; | |
292 | ||
293 | /* | |
294 | * gprs_high are only present for a 31-bit task running on | |
295 | * a 64-bit kernel (see compat_signal.c) but the space for | |
296 | * gprs_high need to be allocated if vector registers are | |
297 | * included in the signal frame on a 31-bit system. | |
298 | */ | |
299 | frame_size = sizeof(*frame) - sizeof(frame->sregs_ext); | |
300 | if (MACHINE_HAS_VX) | |
301 | frame_size += sizeof(frame->sregs_ext); | |
302 | frame = get_sigframe(ka, regs, frame_size); | |
de553438 | 303 | if (frame == (void __user *) -1UL) |
067bf2d4 | 304 | return -EFAULT; |
de553438 | 305 | |
80703617 MS |
306 | /* Set up backchain. */ |
307 | if (__put_user(regs->gprs[15], (addr_t __user *) frame)) | |
067bf2d4 | 308 | return -EFAULT; |
1da177e4 | 309 | |
80703617 MS |
310 | /* Create struct sigcontext on the signal stack */ |
311 | memcpy(&sc.oldmask, &set->sig, _SIGMASK_COPY_SIZE); | |
312 | sc.sregs = (_sigregs __user __force *) &frame->sregs; | |
313 | if (__copy_to_user(&frame->sc, &sc, sizeof(frame->sc))) | |
314 | return -EFAULT; | |
315 | ||
316 | /* Store registers needed to create the signal frame */ | |
317 | store_sigregs(); | |
318 | ||
319 | /* Create _sigregs on the signal stack */ | |
1da177e4 | 320 | if (save_sigregs(regs, &frame->sregs)) |
067bf2d4 | 321 | return -EFAULT; |
80703617 MS |
322 | |
323 | /* Place signal number on stack to allow backtrace from handler. */ | |
324 | if (__put_user(regs->gprs[2], (int __user *) &frame->signo)) | |
325 | return -EFAULT; | |
326 | ||
327 | /* Create _sigregs_ext on the signal stack */ | |
328 | if (save_sigregs_ext(regs, &frame->sregs_ext)) | |
067bf2d4 | 329 | return -EFAULT; |
1da177e4 LT |
330 | |
331 | /* Set up to return from userspace. If provided, use a stub | |
332 | already in userspace. */ | |
333 | if (ka->sa.sa_flags & SA_RESTORER) { | |
fecc868a | 334 | restorer = (unsigned long) ka->sa.sa_restorer; |
1da177e4 | 335 | } else { |
80703617 | 336 | /* Signal frame without vector registers are short ! */ |
37d2cd9d | 337 | __u16 __user *svc = (void __user *) frame + frame_size - 2; |
80703617 | 338 | if (__put_user(S390_SYSCALL_OPCODE | __NR_sigreturn, svc)) |
067bf2d4 | 339 | return -EFAULT; |
fecc868a | 340 | restorer = (unsigned long) svc; |
1da177e4 LT |
341 | } |
342 | ||
1da177e4 | 343 | /* Set up registers for signal handler */ |
80703617 | 344 | regs->gprs[14] = restorer; |
1da177e4 | 345 | regs->gprs[15] = (unsigned long) frame; |
fa968ee2 MS |
346 | /* Force default amode and default user address space control. */ |
347 | regs->psw.mask = PSW_MASK_EA | PSW_MASK_BA | | |
e258d719 | 348 | (PSW_USER_BITS & PSW_MASK_ASC) | |
fa968ee2 | 349 | (regs->psw.mask & ~PSW_MASK_ASC); |
fecc868a | 350 | regs->psw.addr = (unsigned long) ka->sa.sa_handler; |
1da177e4 | 351 | |
6a32591a | 352 | regs->gprs[2] = sig; |
1da177e4 LT |
353 | regs->gprs[3] = (unsigned long) &frame->sc; |
354 | ||
355 | /* We forgot to include these in the sigcontext. | |
356 | To avoid breaking binary compatibility, they are passed as args. */ | |
aa33c8cb MS |
357 | if (sig == SIGSEGV || sig == SIGBUS || sig == SIGILL || |
358 | sig == SIGTRAP || sig == SIGFPE) { | |
359 | /* set extra registers only for synchronous signals */ | |
360 | regs->gprs[4] = regs->int_code & 127; | |
361 | regs->gprs[5] = regs->int_parm_long; | |
362 | regs->gprs[6] = task_thread_info(current)->last_break; | |
363 | } | |
54dfe5dd | 364 | return 0; |
1da177e4 LT |
365 | } |
366 | ||
067bf2d4 RW |
367 | static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, |
368 | struct pt_regs *regs) | |
1da177e4 | 369 | { |
80703617 MS |
370 | struct rt_sigframe __user *frame; |
371 | unsigned long uc_flags, restorer; | |
372 | size_t frame_size; | |
373 | ||
374 | frame_size = sizeof(struct rt_sigframe) - sizeof(_sigregs_ext); | |
375 | /* | |
376 | * gprs_high are only present for a 31-bit task running on | |
377 | * a 64-bit kernel (see compat_signal.c) but the space for | |
378 | * gprs_high need to be allocated if vector registers are | |
379 | * included in the signal frame on a 31-bit system. | |
380 | */ | |
381 | uc_flags = 0; | |
80703617 MS |
382 | if (MACHINE_HAS_VX) { |
383 | frame_size += sizeof(_sigregs_ext); | |
b5510d9b | 384 | uc_flags |= UC_VXRS; |
80703617 | 385 | } |
80703617 | 386 | frame = get_sigframe(&ksig->ka, regs, frame_size); |
de553438 | 387 | if (frame == (void __user *) -1UL) |
067bf2d4 | 388 | return -EFAULT; |
de553438 | 389 | |
80703617 MS |
390 | /* Set up backchain. */ |
391 | if (__put_user(regs->gprs[15], (addr_t __user *) frame)) | |
067bf2d4 | 392 | return -EFAULT; |
1da177e4 LT |
393 | |
394 | /* Set up to return from userspace. If provided, use a stub | |
395 | already in userspace. */ | |
067bf2d4 | 396 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
fecc868a | 397 | restorer = (unsigned long) ksig->ka.sa.sa_restorer; |
1da177e4 | 398 | } else { |
80703617 MS |
399 | __u16 __user *svc = &frame->svc_insn; |
400 | if (__put_user(S390_SYSCALL_OPCODE | __NR_rt_sigreturn, svc)) | |
067bf2d4 | 401 | return -EFAULT; |
fecc868a | 402 | restorer = (unsigned long) svc; |
1da177e4 LT |
403 | } |
404 | ||
80703617 MS |
405 | /* Create siginfo on the signal stack */ |
406 | if (copy_siginfo_to_user(&frame->info, &ksig->info)) | |
407 | return -EFAULT; | |
408 | ||
409 | /* Store registers needed to create the signal frame */ | |
410 | store_sigregs(); | |
411 | ||
412 | /* Create ucontext on the signal stack. */ | |
413 | if (__put_user(uc_flags, &frame->uc.uc_flags) || | |
414 | __put_user(NULL, &frame->uc.uc_link) || | |
415 | __save_altstack(&frame->uc.uc_stack, regs->gprs[15]) || | |
416 | save_sigregs(regs, &frame->uc.uc_mcontext) || | |
417 | __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)) || | |
418 | save_sigregs_ext(regs, &frame->uc.uc_mcontext_ext)) | |
067bf2d4 | 419 | return -EFAULT; |
1da177e4 LT |
420 | |
421 | /* Set up registers for signal handler */ | |
80703617 | 422 | regs->gprs[14] = restorer; |
1da177e4 | 423 | regs->gprs[15] = (unsigned long) frame; |
fa968ee2 MS |
424 | /* Force default amode and default user address space control. */ |
425 | regs->psw.mask = PSW_MASK_EA | PSW_MASK_BA | | |
e258d719 | 426 | (PSW_USER_BITS & PSW_MASK_ASC) | |
fa968ee2 | 427 | (regs->psw.mask & ~PSW_MASK_ASC); |
fecc868a | 428 | regs->psw.addr = (unsigned long) ksig->ka.sa.sa_handler; |
1da177e4 | 429 | |
6a32591a | 430 | regs->gprs[2] = ksig->sig; |
1da177e4 LT |
431 | regs->gprs[3] = (unsigned long) &frame->info; |
432 | regs->gprs[4] = (unsigned long) &frame->uc; | |
86f2552b | 433 | regs->gprs[5] = task_thread_info(current)->last_break; |
54dfe5dd | 434 | return 0; |
1da177e4 LT |
435 | } |
436 | ||
067bf2d4 RW |
437 | static void handle_signal(struct ksignal *ksig, sigset_t *oldset, |
438 | struct pt_regs *regs) | |
1da177e4 | 439 | { |
54dfe5dd HC |
440 | int ret; |
441 | ||
1da177e4 | 442 | /* Set up the stack frame */ |
067bf2d4 RW |
443 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) |
444 | ret = setup_rt_frame(ksig, oldset, regs); | |
1da177e4 | 445 | else |
067bf2d4 RW |
446 | ret = setup_frame(ksig->sig, &ksig->ka, oldset, regs); |
447 | ||
448 | signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLE_STEP)); | |
1da177e4 LT |
449 | } |
450 | ||
451 | /* | |
452 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
453 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
454 | * mistake. | |
455 | * | |
456 | * Note that we go through the signals twice: once to check the signals that | |
457 | * the kernel can handle, and then we build all the user-level signal handling | |
458 | * stack-frames in one go after that. | |
459 | */ | |
54dfe5dd | 460 | void do_signal(struct pt_regs *regs) |
1da177e4 | 461 | { |
067bf2d4 | 462 | struct ksignal ksig; |
b7f9a11a | 463 | sigset_t *oldset = sigmask_to_save(); |
1da177e4 | 464 | |
20b40a79 MS |
465 | /* |
466 | * Get signal to deliver. When running under ptrace, at this point | |
467 | * the debugger may change all our registers, including the system | |
468 | * call information. | |
469 | */ | |
b6ef5bb3 | 470 | current_thread_info()->system_call = |
d3a73acb | 471 | test_pt_regs_flag(regs, PIF_SYSCALL) ? regs->int_code : 0; |
1da177e4 | 472 | |
067bf2d4 | 473 | if (get_signal(&ksig)) { |
1da177e4 | 474 | /* Whee! Actually deliver the signal. */ |
b6ef5bb3 | 475 | if (current_thread_info()->system_call) { |
aa33c8cb | 476 | regs->int_code = current_thread_info()->system_call; |
20b40a79 MS |
477 | /* Check for system call restarting. */ |
478 | switch (regs->gprs[2]) { | |
479 | case -ERESTART_RESTARTBLOCK: | |
480 | case -ERESTARTNOHAND: | |
481 | regs->gprs[2] = -EINTR; | |
482 | break; | |
483 | case -ERESTARTSYS: | |
067bf2d4 | 484 | if (!(ksig.ka.sa.sa_flags & SA_RESTART)) { |
20b40a79 MS |
485 | regs->gprs[2] = -EINTR; |
486 | break; | |
487 | } | |
488 | /* fallthrough */ | |
489 | case -ERESTARTNOINTR: | |
490 | regs->gprs[2] = regs->orig_gpr2; | |
ccf45caf MS |
491 | regs->psw.addr = |
492 | __rewind_psw(regs->psw, | |
aa33c8cb | 493 | regs->int_code >> 16); |
20b40a79 MS |
494 | break; |
495 | } | |
20b40a79 | 496 | } |
d9ae6772 | 497 | /* No longer in a system call */ |
d3a73acb | 498 | clear_pt_regs_flag(regs, PIF_SYSCALL); |
20b40a79 | 499 | |
a610d6e6 | 500 | if (is_compat_task()) |
067bf2d4 | 501 | handle_signal32(&ksig, oldset, regs); |
a610d6e6 | 502 | else |
067bf2d4 | 503 | handle_signal(&ksig, oldset, regs); |
54dfe5dd HC |
504 | return; |
505 | } | |
506 | ||
20b40a79 | 507 | /* No handlers present - check for system call restart */ |
d3a73acb | 508 | clear_pt_regs_flag(regs, PIF_SYSCALL); |
b6ef5bb3 | 509 | if (current_thread_info()->system_call) { |
aa33c8cb | 510 | regs->int_code = current_thread_info()->system_call; |
20b40a79 MS |
511 | switch (regs->gprs[2]) { |
512 | case -ERESTART_RESTARTBLOCK: | |
513 | /* Restart with sys_restart_syscall */ | |
aa33c8cb | 514 | regs->int_code = __NR_restart_syscall; |
20b40a79 MS |
515 | /* fallthrough */ |
516 | case -ERESTARTNOHAND: | |
517 | case -ERESTARTSYS: | |
518 | case -ERESTARTNOINTR: | |
519 | /* Restart system call with magic TIF bit. */ | |
520 | regs->gprs[2] = regs->orig_gpr2; | |
d3a73acb | 521 | set_pt_regs_flag(regs, PIF_SYSCALL); |
39efd4ec | 522 | if (test_thread_flag(TIF_SINGLE_STEP)) |
d3a73acb | 523 | clear_pt_regs_flag(regs, PIF_PER_TRAP); |
b6ef5bb3 | 524 | break; |
20b40a79 MS |
525 | } |
526 | } | |
527 | ||
54dfe5dd HC |
528 | /* |
529 | * If there's no signal to deliver, we just put the saved sigmask back. | |
530 | */ | |
51a7b448 | 531 | restore_saved_sigmask(); |
1da177e4 | 532 | } |
753c4dd6 MS |
533 | |
534 | void do_notify_resume(struct pt_regs *regs) | |
535 | { | |
536 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
537 | tracehook_notify_resume(regs); | |
538 | } |