Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Architecture-specific signal handling support. | |
3 | * | |
4 | * Copyright (C) 1999-2004 Hewlett-Packard Co | |
5 | * David Mosberger-Tang <davidm@hpl.hp.com> | |
6 | * | |
7 | * Derived from i386 and Alpha versions. | |
8 | */ | |
9 | ||
1da177e4 LT |
10 | #include <linux/errno.h> |
11 | #include <linux/kernel.h> | |
12 | #include <linux/mm.h> | |
13 | #include <linux/ptrace.h> | |
f14488cc | 14 | #include <linux/tracehook.h> |
1da177e4 LT |
15 | #include <linux/sched.h> |
16 | #include <linux/signal.h> | |
17 | #include <linux/smp.h> | |
1da177e4 LT |
18 | #include <linux/stddef.h> |
19 | #include <linux/tty.h> | |
20 | #include <linux/binfmts.h> | |
21 | #include <linux/unistd.h> | |
22 | #include <linux/wait.h> | |
23 | ||
1da177e4 LT |
24 | #include <asm/intrinsics.h> |
25 | #include <asm/uaccess.h> | |
26 | #include <asm/rse.h> | |
27 | #include <asm/sigcontext.h> | |
28 | ||
29 | #include "sigframe.h" | |
30 | ||
31 | #define DEBUG_SIG 0 | |
32 | #define STACK_ALIGN 16 /* minimal alignment for stack pointer */ | |
33 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) | |
34 | ||
35 | #if _NSIG_WORDS > 1 | |
36 | # define PUT_SIGSET(k,u) __copy_to_user((u)->sig, (k)->sig, sizeof(sigset_t)) | |
37 | # define GET_SIGSET(k,u) __copy_from_user((k)->sig, (u)->sig, sizeof(sigset_t)) | |
38 | #else | |
39 | # define PUT_SIGSET(k,u) __put_user((k)->sig[0], &(u)->sig[0]) | |
40 | # define GET_SIGSET(k,u) __get_user((k)->sig[0], &(u)->sig[0]) | |
41 | #endif | |
42 | ||
1da177e4 LT |
43 | asmlinkage long |
44 | sys_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, long arg2, | |
45 | long arg3, long arg4, long arg5, long arg6, long arg7, | |
46 | struct pt_regs regs) | |
47 | { | |
48 | return do_sigaltstack(uss, uoss, regs.r12); | |
49 | } | |
50 | ||
51 | static long | |
52 | restore_sigcontext (struct sigcontext __user *sc, struct sigscratch *scr) | |
53 | { | |
4ea78729 | 54 | unsigned long ip, flags, nat, um, cfm, rsc; |
1da177e4 LT |
55 | long err; |
56 | ||
57 | /* Always make any pending restarted system calls return -EINTR */ | |
58 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
59 | ||
60 | /* restore scratch that always needs gets updated during signal delivery: */ | |
61 | err = __get_user(flags, &sc->sc_flags); | |
62 | err |= __get_user(nat, &sc->sc_nat); | |
63 | err |= __get_user(ip, &sc->sc_ip); /* instruction pointer */ | |
64 | err |= __get_user(cfm, &sc->sc_cfm); | |
65 | err |= __get_user(um, &sc->sc_um); /* user mask */ | |
4ea78729 | 66 | err |= __get_user(rsc, &sc->sc_ar_rsc); |
1da177e4 LT |
67 | err |= __get_user(scr->pt.ar_unat, &sc->sc_ar_unat); |
68 | err |= __get_user(scr->pt.ar_fpsr, &sc->sc_ar_fpsr); | |
69 | err |= __get_user(scr->pt.ar_pfs, &sc->sc_ar_pfs); | |
70 | err |= __get_user(scr->pt.pr, &sc->sc_pr); /* predicates */ | |
71 | err |= __get_user(scr->pt.b0, &sc->sc_br[0]); /* b0 (rp) */ | |
72 | err |= __get_user(scr->pt.b6, &sc->sc_br[6]); /* b6 */ | |
73 | err |= __copy_from_user(&scr->pt.r1, &sc->sc_gr[1], 8); /* r1 */ | |
74 | err |= __copy_from_user(&scr->pt.r8, &sc->sc_gr[8], 4*8); /* r8-r11 */ | |
75 | err |= __copy_from_user(&scr->pt.r12, &sc->sc_gr[12], 2*8); /* r12-r13 */ | |
76 | err |= __copy_from_user(&scr->pt.r15, &sc->sc_gr[15], 8); /* r15 */ | |
77 | ||
78 | scr->pt.cr_ifs = cfm | (1UL << 63); | |
4ea78729 | 79 | scr->pt.ar_rsc = rsc | (3 << 2); /* force PL3 */ |
1da177e4 LT |
80 | |
81 | /* establish new instruction pointer: */ | |
82 | scr->pt.cr_iip = ip & ~0x3UL; | |
83 | ia64_psr(&scr->pt)->ri = ip & 0x3; | |
84 | scr->pt.cr_ipsr = (scr->pt.cr_ipsr & ~IA64_PSR_UM) | (um & IA64_PSR_UM); | |
85 | ||
86 | scr->scratch_unat = ia64_put_scratch_nat_bits(&scr->pt, nat); | |
87 | ||
88 | if (!(flags & IA64_SC_FLAG_IN_SYSCALL)) { | |
89 | /* Restore most scratch-state only when not in syscall. */ | |
90 | err |= __get_user(scr->pt.ar_ccv, &sc->sc_ar_ccv); /* ar.ccv */ | |
91 | err |= __get_user(scr->pt.b7, &sc->sc_br[7]); /* b7 */ | |
92 | err |= __get_user(scr->pt.r14, &sc->sc_gr[14]); /* r14 */ | |
93 | err |= __copy_from_user(&scr->pt.ar_csd, &sc->sc_ar25, 2*8); /* ar.csd & ar.ssd */ | |
94 | err |= __copy_from_user(&scr->pt.r2, &sc->sc_gr[2], 2*8); /* r2-r3 */ | |
95 | err |= __copy_from_user(&scr->pt.r16, &sc->sc_gr[16], 16*8); /* r16-r31 */ | |
96 | } | |
97 | ||
98 | if ((flags & IA64_SC_FLAG_FPH_VALID) != 0) { | |
99 | struct ia64_psr *psr = ia64_psr(&scr->pt); | |
100 | ||
b9ab117c | 101 | err |= __copy_from_user(current->thread.fph, &sc->sc_fr[32], 96*16); |
1da177e4 | 102 | psr->mfh = 0; /* drop signal handler's fph contents... */ |
2ba3e3e6 | 103 | preempt_disable(); |
1da177e4 LT |
104 | if (psr->dfh) |
105 | ia64_drop_fpu(current); | |
106 | else { | |
107 | /* We already own the local fph, otherwise psr->dfh wouldn't be 0. */ | |
108 | __ia64_load_fpu(current->thread.fph); | |
109 | ia64_set_local_fpu_owner(current); | |
110 | } | |
2ba3e3e6 | 111 | preempt_enable(); |
1da177e4 LT |
112 | } |
113 | return err; | |
114 | } | |
115 | ||
116 | int | |
117 | copy_siginfo_to_user (siginfo_t __user *to, siginfo_t *from) | |
118 | { | |
119 | if (!access_ok(VERIFY_WRITE, to, sizeof(siginfo_t))) | |
120 | return -EFAULT; | |
121 | if (from->si_code < 0) { | |
122 | if (__copy_to_user(to, from, sizeof(siginfo_t))) | |
123 | return -EFAULT; | |
124 | return 0; | |
125 | } else { | |
126 | int err; | |
127 | ||
128 | /* | |
129 | * If you change siginfo_t structure, please be sure this code is fixed | |
130 | * accordingly. It should never copy any pad contained in the structure | |
131 | * to avoid security leaks, but must copy the generic 3 ints plus the | |
132 | * relevant union member. | |
133 | */ | |
134 | err = __put_user(from->si_signo, &to->si_signo); | |
135 | err |= __put_user(from->si_errno, &to->si_errno); | |
136 | err |= __put_user((short)from->si_code, &to->si_code); | |
137 | switch (from->si_code >> 16) { | |
138 | case __SI_FAULT >> 16: | |
139 | err |= __put_user(from->si_flags, &to->si_flags); | |
140 | err |= __put_user(from->si_isr, &to->si_isr); | |
141 | case __SI_POLL >> 16: | |
142 | err |= __put_user(from->si_addr, &to->si_addr); | |
143 | err |= __put_user(from->si_imm, &to->si_imm); | |
144 | break; | |
145 | case __SI_TIMER >> 16: | |
146 | err |= __put_user(from->si_tid, &to->si_tid); | |
147 | err |= __put_user(from->si_overrun, &to->si_overrun); | |
148 | err |= __put_user(from->si_ptr, &to->si_ptr); | |
149 | break; | |
150 | case __SI_RT >> 16: /* Not generated by the kernel as of now. */ | |
151 | case __SI_MESGQ >> 16: | |
152 | err |= __put_user(from->si_uid, &to->si_uid); | |
153 | err |= __put_user(from->si_pid, &to->si_pid); | |
154 | err |= __put_user(from->si_ptr, &to->si_ptr); | |
155 | break; | |
156 | case __SI_CHLD >> 16: | |
157 | err |= __put_user(from->si_utime, &to->si_utime); | |
158 | err |= __put_user(from->si_stime, &to->si_stime); | |
159 | err |= __put_user(from->si_status, &to->si_status); | |
160 | default: | |
161 | err |= __put_user(from->si_uid, &to->si_uid); | |
162 | err |= __put_user(from->si_pid, &to->si_pid); | |
163 | break; | |
164 | } | |
165 | return err; | |
166 | } | |
167 | } | |
168 | ||
169 | long | |
170 | ia64_rt_sigreturn (struct sigscratch *scr) | |
171 | { | |
172 | extern char ia64_strace_leave_kernel, ia64_leave_kernel; | |
173 | struct sigcontext __user *sc; | |
174 | struct siginfo si; | |
175 | sigset_t set; | |
176 | long retval; | |
177 | ||
178 | sc = &((struct sigframe __user *) (scr->pt.r12 + 16))->sc; | |
179 | ||
180 | /* | |
181 | * When we return to the previously executing context, r8 and r10 have already | |
182 | * been setup the way we want them. Indeed, if the signal wasn't delivered while | |
183 | * in a system call, we must not touch r8 or r10 as otherwise user-level state | |
184 | * could be corrupted. | |
185 | */ | |
186 | retval = (long) &ia64_leave_kernel; | |
446b8831 DW |
187 | if (test_thread_flag(TIF_SYSCALL_TRACE) |
188 | || test_thread_flag(TIF_SYSCALL_AUDIT)) | |
1da177e4 LT |
189 | /* |
190 | * strace expects to be notified after sigreturn returns even though the | |
191 | * context to which we return may not be in the middle of a syscall. | |
192 | * Thus, the return-value that strace displays for sigreturn is | |
193 | * meaningless. | |
194 | */ | |
195 | retval = (long) &ia64_strace_leave_kernel; | |
196 | ||
197 | if (!access_ok(VERIFY_READ, sc, sizeof(*sc))) | |
198 | goto give_sigsegv; | |
199 | ||
200 | if (GET_SIGSET(&set, &sc->sc_mask)) | |
201 | goto give_sigsegv; | |
202 | ||
203 | sigdelsetmask(&set, ~_BLOCKABLE); | |
204 | ||
205 | spin_lock_irq(¤t->sighand->siglock); | |
206 | { | |
207 | current->blocked = set; | |
208 | recalc_sigpending(); | |
209 | } | |
210 | spin_unlock_irq(¤t->sighand->siglock); | |
211 | ||
212 | if (restore_sigcontext(sc, scr)) | |
213 | goto give_sigsegv; | |
214 | ||
215 | #if DEBUG_SIG | |
216 | printk("SIG return (%s:%d): sp=%lx ip=%lx\n", | |
217 | current->comm, current->pid, scr->pt.r12, scr->pt.cr_iip); | |
218 | #endif | |
219 | /* | |
220 | * It is more difficult to avoid calling this function than to | |
221 | * call it and ignore errors. | |
222 | */ | |
223 | do_sigaltstack(&sc->sc_stack, NULL, scr->pt.r12); | |
224 | return retval; | |
225 | ||
226 | give_sigsegv: | |
227 | si.si_signo = SIGSEGV; | |
228 | si.si_errno = 0; | |
229 | si.si_code = SI_KERNEL; | |
b488893a | 230 | si.si_pid = task_pid_vnr(current); |
ef81ee98 | 231 | si.si_uid = current_uid(); |
1da177e4 LT |
232 | si.si_addr = sc; |
233 | force_sig_info(SIGSEGV, &si, current); | |
234 | return retval; | |
235 | } | |
236 | ||
237 | /* | |
238 | * This does just the minimum required setup of sigcontext. | |
239 | * Specifically, it only installs data that is either not knowable at | |
240 | * the user-level or that gets modified before execution in the | |
241 | * trampoline starts. Everything else is done at the user-level. | |
242 | */ | |
243 | static long | |
244 | setup_sigcontext (struct sigcontext __user *sc, sigset_t *mask, struct sigscratch *scr) | |
245 | { | |
246 | unsigned long flags = 0, ifs, cfm, nat; | |
b9ab117c | 247 | long err = 0; |
1da177e4 LT |
248 | |
249 | ifs = scr->pt.cr_ifs; | |
250 | ||
251 | if (on_sig_stack((unsigned long) sc)) | |
252 | flags |= IA64_SC_FLAG_ONSTACK; | |
253 | if ((ifs & (1UL << 63)) == 0) | |
254 | /* if cr_ifs doesn't have the valid bit set, we got here through a syscall */ | |
255 | flags |= IA64_SC_FLAG_IN_SYSCALL; | |
256 | cfm = ifs & ((1UL << 38) - 1); | |
257 | ia64_flush_fph(current); | |
258 | if ((current->thread.flags & IA64_THREAD_FPH_VALID)) { | |
259 | flags |= IA64_SC_FLAG_FPH_VALID; | |
b9ab117c | 260 | err = __copy_to_user(&sc->sc_fr[32], current->thread.fph, 96*16); |
1da177e4 LT |
261 | } |
262 | ||
263 | nat = ia64_get_scratch_nat_bits(&scr->pt, scr->scratch_unat); | |
264 | ||
b9ab117c | 265 | err |= __put_user(flags, &sc->sc_flags); |
1da177e4 LT |
266 | err |= __put_user(nat, &sc->sc_nat); |
267 | err |= PUT_SIGSET(mask, &sc->sc_mask); | |
268 | err |= __put_user(cfm, &sc->sc_cfm); | |
269 | err |= __put_user(scr->pt.cr_ipsr & IA64_PSR_UM, &sc->sc_um); | |
270 | err |= __put_user(scr->pt.ar_rsc, &sc->sc_ar_rsc); | |
271 | err |= __put_user(scr->pt.ar_unat, &sc->sc_ar_unat); /* ar.unat */ | |
272 | err |= __put_user(scr->pt.ar_fpsr, &sc->sc_ar_fpsr); /* ar.fpsr */ | |
273 | err |= __put_user(scr->pt.ar_pfs, &sc->sc_ar_pfs); | |
274 | err |= __put_user(scr->pt.pr, &sc->sc_pr); /* predicates */ | |
275 | err |= __put_user(scr->pt.b0, &sc->sc_br[0]); /* b0 (rp) */ | |
276 | err |= __put_user(scr->pt.b6, &sc->sc_br[6]); /* b6 */ | |
277 | err |= __copy_to_user(&sc->sc_gr[1], &scr->pt.r1, 8); /* r1 */ | |
278 | err |= __copy_to_user(&sc->sc_gr[8], &scr->pt.r8, 4*8); /* r8-r11 */ | |
279 | err |= __copy_to_user(&sc->sc_gr[12], &scr->pt.r12, 2*8); /* r12-r13 */ | |
280 | err |= __copy_to_user(&sc->sc_gr[15], &scr->pt.r15, 8); /* r15 */ | |
281 | err |= __put_user(scr->pt.cr_iip + ia64_psr(&scr->pt)->ri, &sc->sc_ip); | |
282 | ||
2018df76 | 283 | if (!(flags & IA64_SC_FLAG_IN_SYSCALL)) { |
1da177e4 LT |
284 | /* Copy scratch regs to sigcontext if the signal didn't interrupt a syscall. */ |
285 | err |= __put_user(scr->pt.ar_ccv, &sc->sc_ar_ccv); /* ar.ccv */ | |
286 | err |= __put_user(scr->pt.b7, &sc->sc_br[7]); /* b7 */ | |
287 | err |= __put_user(scr->pt.r14, &sc->sc_gr[14]); /* r14 */ | |
288 | err |= __copy_to_user(&sc->sc_ar25, &scr->pt.ar_csd, 2*8); /* ar.csd & ar.ssd */ | |
289 | err |= __copy_to_user(&sc->sc_gr[2], &scr->pt.r2, 2*8); /* r2-r3 */ | |
290 | err |= __copy_to_user(&sc->sc_gr[16], &scr->pt.r16, 16*8); /* r16-r31 */ | |
291 | } | |
292 | return err; | |
293 | } | |
294 | ||
295 | /* | |
296 | * Check whether the register-backing store is already on the signal stack. | |
297 | */ | |
298 | static inline int | |
299 | rbs_on_sig_stack (unsigned long bsp) | |
300 | { | |
301 | return (bsp - current->sas_ss_sp < current->sas_ss_size); | |
302 | } | |
303 | ||
304 | static long | |
305 | force_sigsegv_info (int sig, void __user *addr) | |
306 | { | |
307 | unsigned long flags; | |
308 | struct siginfo si; | |
309 | ||
310 | if (sig == SIGSEGV) { | |
311 | /* | |
312 | * Acquiring siglock around the sa_handler-update is almost | |
313 | * certainly overkill, but this isn't a | |
314 | * performance-critical path and I'd rather play it safe | |
315 | * here than having to debug a nasty race if and when | |
316 | * something changes in kernel/signal.c that would make it | |
317 | * no longer safe to modify sa_handler without holding the | |
318 | * lock. | |
319 | */ | |
320 | spin_lock_irqsave(¤t->sighand->siglock, flags); | |
321 | current->sighand->action[sig - 1].sa.sa_handler = SIG_DFL; | |
322 | spin_unlock_irqrestore(¤t->sighand->siglock, flags); | |
323 | } | |
324 | si.si_signo = SIGSEGV; | |
325 | si.si_errno = 0; | |
326 | si.si_code = SI_KERNEL; | |
b488893a | 327 | si.si_pid = task_pid_vnr(current); |
ef81ee98 | 328 | si.si_uid = current_uid(); |
1da177e4 LT |
329 | si.si_addr = addr; |
330 | force_sig_info(SIGSEGV, &si, current); | |
331 | return 0; | |
332 | } | |
333 | ||
334 | static long | |
335 | setup_frame (int sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *set, | |
336 | struct sigscratch *scr) | |
337 | { | |
338 | extern char __kernel_sigtramp[]; | |
cf20d1ea | 339 | unsigned long tramp_addr, new_rbs = 0, new_sp; |
1da177e4 LT |
340 | struct sigframe __user *frame; |
341 | long err; | |
342 | ||
cf20d1ea | 343 | new_sp = scr->pt.r12; |
1da177e4 | 344 | tramp_addr = (unsigned long) __kernel_sigtramp; |
d7a6c68a SW |
345 | if (ka->sa.sa_flags & SA_ONSTACK) { |
346 | int onstack = sas_ss_flags(new_sp); | |
347 | ||
348 | if (onstack == 0) { | |
349 | new_sp = current->sas_ss_sp + current->sas_ss_size; | |
350 | /* | |
351 | * We need to check for the register stack being on the | |
352 | * signal stack separately, because it's switched | |
353 | * separately (memory stack is switched in the kernel, | |
354 | * register stack is switched in the signal trampoline). | |
355 | */ | |
356 | if (!rbs_on_sig_stack(scr->pt.ar_bspstore)) | |
357 | new_rbs = ALIGN(current->sas_ss_sp, | |
358 | sizeof(long)); | |
359 | } else if (onstack == SS_ONSTACK) { | |
360 | unsigned long check_sp; | |
361 | ||
362 | /* | |
363 | * If we are on the alternate signal stack and would | |
364 | * overflow it, don't. Return an always-bogus address | |
365 | * instead so we will die with SIGSEGV. | |
366 | */ | |
367 | check_sp = (new_sp - sizeof(*frame)) & -STACK_ALIGN; | |
368 | if (!likely(on_sig_stack(check_sp))) | |
369 | return force_sigsegv_info(sig, (void __user *) | |
370 | check_sp); | |
371 | } | |
1da177e4 | 372 | } |
cf20d1ea | 373 | frame = (void __user *) ((new_sp - sizeof(*frame)) & -STACK_ALIGN); |
1da177e4 LT |
374 | |
375 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) | |
376 | return force_sigsegv_info(sig, frame); | |
377 | ||
378 | err = __put_user(sig, &frame->arg0); | |
379 | err |= __put_user(&frame->info, &frame->arg1); | |
380 | err |= __put_user(&frame->sc, &frame->arg2); | |
381 | err |= __put_user(new_rbs, &frame->sc.sc_rbs_base); | |
382 | err |= __put_user(0, &frame->sc.sc_loadrs); /* initialize to zero */ | |
383 | err |= __put_user(ka->sa.sa_handler, &frame->handler); | |
384 | ||
385 | err |= copy_siginfo_to_user(&frame->info, info); | |
386 | ||
387 | err |= __put_user(current->sas_ss_sp, &frame->sc.sc_stack.ss_sp); | |
388 | err |= __put_user(current->sas_ss_size, &frame->sc.sc_stack.ss_size); | |
389 | err |= __put_user(sas_ss_flags(scr->pt.r12), &frame->sc.sc_stack.ss_flags); | |
390 | err |= setup_sigcontext(&frame->sc, set, scr); | |
391 | ||
392 | if (unlikely(err)) | |
393 | return force_sigsegv_info(sig, frame); | |
394 | ||
395 | scr->pt.r12 = (unsigned long) frame - 16; /* new stack pointer */ | |
396 | scr->pt.ar_fpsr = FPSR_DEFAULT; /* reset fpsr for signal handler */ | |
397 | scr->pt.cr_iip = tramp_addr; | |
398 | ia64_psr(&scr->pt)->ri = 0; /* start executing in first slot */ | |
399 | ia64_psr(&scr->pt)->be = 0; /* force little-endian byte-order */ | |
400 | /* | |
401 | * Force the interruption function mask to zero. This has no effect when a | |
402 | * system-call got interrupted by a signal (since, in that case, scr->pt_cr_ifs is | |
403 | * ignored), but it has the desirable effect of making it possible to deliver a | |
404 | * signal with an incomplete register frame (which happens when a mandatory RSE | |
405 | * load faults). Furthermore, it has no negative effect on the getting the user's | |
406 | * dirty partition preserved, because that's governed by scr->pt.loadrs. | |
407 | */ | |
408 | scr->pt.cr_ifs = (1UL << 63); | |
409 | ||
410 | /* | |
411 | * Note: this affects only the NaT bits of the scratch regs (the ones saved in | |
412 | * pt_regs), which is exactly what we want. | |
413 | */ | |
414 | scr->scratch_unat = 0; /* ensure NaT bits of r12 is clear */ | |
415 | ||
416 | #if DEBUG_SIG | |
417 | printk("SIG deliver (%s:%d): sig=%d sp=%lx ip=%lx handler=%p\n", | |
418 | current->comm, current->pid, sig, scr->pt.r12, frame->sc.sc_ip, frame->handler); | |
419 | #endif | |
420 | return 1; | |
421 | } | |
422 | ||
423 | static long | |
424 | handle_signal (unsigned long sig, struct k_sigaction *ka, siginfo_t *info, sigset_t *oldset, | |
425 | struct sigscratch *scr) | |
426 | { | |
32974ad4 TL |
427 | if (!setup_frame(sig, ka, info, oldset, scr)) |
428 | return 0; | |
1da177e4 | 429 | |
69be8f18 SR |
430 | spin_lock_irq(¤t->sighand->siglock); |
431 | sigorsets(¤t->blocked, ¤t->blocked, &ka->sa.sa_mask); | |
432 | if (!(ka->sa.sa_flags & SA_NODEFER)) | |
433 | sigaddset(¤t->blocked, sig); | |
434 | recalc_sigpending(); | |
435 | spin_unlock_irq(¤t->sighand->siglock); | |
f14488cc SL |
436 | |
437 | /* | |
438 | * Let tracing know that we've done the handler setup. | |
439 | */ | |
440 | tracehook_signal_handler(sig, info, ka, &scr->pt, | |
441 | test_thread_flag(TIF_SINGLESTEP)); | |
442 | ||
1da177e4 LT |
443 | return 1; |
444 | } | |
445 | ||
446 | /* | |
447 | * Note that `init' is a special process: it doesn't get signals it doesn't want to | |
448 | * handle. Thus you cannot kill init even with a SIGKILL even by mistake. | |
449 | */ | |
4a177cbf AD |
450 | void |
451 | ia64_do_signal (struct sigscratch *scr, long in_syscall) | |
1da177e4 LT |
452 | { |
453 | struct k_sigaction ka; | |
4a177cbf | 454 | sigset_t *oldset; |
1da177e4 LT |
455 | siginfo_t info; |
456 | long restart = in_syscall; | |
457 | long errno = scr->pt.r8; | |
1da177e4 LT |
458 | |
459 | /* | |
460 | * In the ia64_leave_kernel code path, we want the common case to go fast, which | |
461 | * is why we may in certain cases get here from kernel mode. Just return without | |
462 | * doing anything if so. | |
463 | */ | |
464 | if (!user_mode(&scr->pt)) | |
4a177cbf | 465 | return; |
1da177e4 | 466 | |
848376c7 | 467 | if (current_thread_info()->status & TS_RESTORE_SIGMASK) |
4a177cbf AD |
468 | oldset = ¤t->saved_sigmask; |
469 | else | |
1da177e4 LT |
470 | oldset = ¤t->blocked; |
471 | ||
472 | /* | |
473 | * This only loops in the rare cases of handle_signal() failing, in which case we | |
474 | * need to push through a forced SIGSEGV. | |
475 | */ | |
476 | while (1) { | |
477 | int signr = get_signal_to_deliver(&info, &ka, &scr->pt, NULL); | |
478 | ||
479 | /* | |
480 | * get_signal_to_deliver() may have run a debugger (via notify_parent()) | |
481 | * and the debugger may have modified the state (e.g., to arrange for an | |
482 | * inferior call), thus it's important to check for restarting _after_ | |
483 | * get_signal_to_deliver(). | |
484 | */ | |
32974ad4 | 485 | if ((long) scr->pt.r10 != -1) |
1da177e4 LT |
486 | /* |
487 | * A system calls has to be restarted only if one of the error codes | |
488 | * ERESTARTNOHAND, ERESTARTSYS, or ERESTARTNOINTR is returned. If r10 | |
489 | * isn't -1 then r8 doesn't hold an error code and we don't need to | |
490 | * restart the syscall, so we can clear the "restart" flag here. | |
491 | */ | |
492 | restart = 0; | |
493 | ||
494 | if (signr <= 0) | |
495 | break; | |
496 | ||
497 | if (unlikely(restart)) { | |
498 | switch (errno) { | |
499 | case ERESTART_RESTARTBLOCK: | |
500 | case ERESTARTNOHAND: | |
32974ad4 | 501 | scr->pt.r8 = EINTR; |
1da177e4 LT |
502 | /* note: scr->pt.r10 is already -1 */ |
503 | break; | |
504 | ||
505 | case ERESTARTSYS: | |
506 | if ((ka.sa.sa_flags & SA_RESTART) == 0) { | |
32974ad4 | 507 | scr->pt.r8 = EINTR; |
1da177e4 LT |
508 | /* note: scr->pt.r10 is already -1 */ |
509 | break; | |
510 | } | |
511 | case ERESTARTNOINTR: | |
32974ad4 | 512 | ia64_decrement_ip(&scr->pt); |
1da177e4 LT |
513 | restart = 0; /* don't restart twice if handle_signal() fails... */ |
514 | } | |
515 | } | |
516 | ||
517 | /* | |
518 | * Whee! Actually deliver the signal. If the delivery failed, we need to | |
519 | * continue to iterate in this loop so we can deliver the SIGSEGV... | |
520 | */ | |
4a177cbf | 521 | if (handle_signal(signr, &ka, &info, oldset, scr)) { |
848376c7 RM |
522 | /* |
523 | * A signal was successfully delivered; the saved | |
4a177cbf AD |
524 | * sigmask will have been stored in the signal frame, |
525 | * and will be restored by sigreturn, so we can simply | |
848376c7 RM |
526 | * clear the TS_RESTORE_SIGMASK flag. |
527 | */ | |
528 | current_thread_info()->status &= ~TS_RESTORE_SIGMASK; | |
4a177cbf AD |
529 | return; |
530 | } | |
1da177e4 LT |
531 | } |
532 | ||
533 | /* Did we come from a system call? */ | |
534 | if (restart) { | |
535 | /* Restart the system call - no handlers present */ | |
536 | if (errno == ERESTARTNOHAND || errno == ERESTARTSYS || errno == ERESTARTNOINTR | |
537 | || errno == ERESTART_RESTARTBLOCK) | |
538 | { | |
32974ad4 TL |
539 | /* |
540 | * Note: the syscall number is in r15 which is saved in | |
541 | * pt_regs so all we need to do here is adjust ip so that | |
542 | * the "break" instruction gets re-executed. | |
543 | */ | |
544 | ia64_decrement_ip(&scr->pt); | |
545 | if (errno == ERESTART_RESTARTBLOCK) | |
546 | scr->pt.r15 = __NR_restart_syscall; | |
1da177e4 LT |
547 | } |
548 | } | |
4a177cbf AD |
549 | |
550 | /* if there's no signal to deliver, we just put the saved sigmask | |
551 | * back */ | |
848376c7 RM |
552 | if (current_thread_info()->status & TS_RESTORE_SIGMASK) { |
553 | current_thread_info()->status &= ~TS_RESTORE_SIGMASK; | |
4a177cbf AD |
554 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); |
555 | } | |
1da177e4 | 556 | } |