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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/arch/arm/kernel/signal.c | |
3 | * | |
ab72b007 | 4 | * Copyright (C) 1995-2009 Russell King |
1da177e4 LT |
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 version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | */ | |
1da177e4 LT |
10 | #include <linux/errno.h> |
11 | #include <linux/signal.h> | |
1da177e4 | 12 | #include <linux/personality.h> |
33fa9b13 | 13 | #include <linux/uaccess.h> |
733e5e4b | 14 | #include <linux/tracehook.h> |
1da177e4 | 15 | |
ee90dabc | 16 | #include <asm/elf.h> |
1da177e4 LT |
17 | #include <asm/cacheflush.h> |
18 | #include <asm/ucontext.h> | |
1da177e4 | 19 | #include <asm/unistd.h> |
82c6f5a5 | 20 | #include <asm/vfp.h> |
1da177e4 | 21 | |
e00d349e | 22 | #include "signal.h" |
1da177e4 | 23 | |
1da177e4 LT |
24 | /* |
25 | * For ARM syscalls, we encode the syscall number into the instruction. | |
26 | */ | |
ee4cd588 | 27 | #define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn)|(__NR_OABI_SYSCALL_BASE)) |
28 | #define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn)|(__NR_OABI_SYSCALL_BASE)) | |
1da177e4 | 29 | |
fcca538b NP |
30 | /* |
31 | * With EABI, the syscall number has to be loaded into r7. | |
32 | */ | |
33 | #define MOV_R7_NR_SIGRETURN (0xe3a07000 | (__NR_sigreturn - __NR_SYSCALL_BASE)) | |
34 | #define MOV_R7_NR_RT_SIGRETURN (0xe3a07000 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE)) | |
35 | ||
1da177e4 LT |
36 | /* |
37 | * For Thumb syscalls, we pass the syscall number via r7. We therefore | |
38 | * need two 16-bit instructions. | |
39 | */ | |
40 | #define SWI_THUMB_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_sigreturn - __NR_SYSCALL_BASE)) | |
41 | #define SWI_THUMB_RT_SIGRETURN (0xdf00 << 16 | 0x2700 | (__NR_rt_sigreturn - __NR_SYSCALL_BASE)) | |
42 | ||
fcca538b NP |
43 | const unsigned long sigreturn_codes[7] = { |
44 | MOV_R7_NR_SIGRETURN, SWI_SYS_SIGRETURN, SWI_THUMB_SIGRETURN, | |
45 | MOV_R7_NR_RT_SIGRETURN, SWI_SYS_RT_SIGRETURN, SWI_THUMB_RT_SIGRETURN, | |
1da177e4 LT |
46 | }; |
47 | ||
3bec6ded | 48 | #ifdef CONFIG_CRUNCH |
65a5053b | 49 | static int preserve_crunch_context(struct crunch_sigframe __user *frame) |
3bec6ded LB |
50 | { |
51 | char kbuf[sizeof(*frame) + 8]; | |
52 | struct crunch_sigframe *kframe; | |
53 | ||
54 | /* the crunch context must be 64 bit aligned */ | |
55 | kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7); | |
56 | kframe->magic = CRUNCH_MAGIC; | |
57 | kframe->size = CRUNCH_STORAGE_SIZE; | |
58 | crunch_task_copy(current_thread_info(), &kframe->storage); | |
59 | return __copy_to_user(frame, kframe, sizeof(*frame)); | |
60 | } | |
61 | ||
65a5053b | 62 | static int restore_crunch_context(struct crunch_sigframe __user *frame) |
3bec6ded LB |
63 | { |
64 | char kbuf[sizeof(*frame) + 8]; | |
65 | struct crunch_sigframe *kframe; | |
66 | ||
67 | /* the crunch context must be 64 bit aligned */ | |
68 | kframe = (struct crunch_sigframe *)((unsigned long)(kbuf + 8) & ~7); | |
69 | if (__copy_from_user(kframe, frame, sizeof(*frame))) | |
70 | return -1; | |
71 | if (kframe->magic != CRUNCH_MAGIC || | |
72 | kframe->size != CRUNCH_STORAGE_SIZE) | |
73 | return -1; | |
74 | crunch_task_restore(current_thread_info(), &kframe->storage); | |
75 | return 0; | |
76 | } | |
77 | #endif | |
78 | ||
1da177e4 LT |
79 | #ifdef CONFIG_IWMMXT |
80 | ||
1da177e4 LT |
81 | static int preserve_iwmmxt_context(struct iwmmxt_sigframe *frame) |
82 | { | |
69b04754 HD |
83 | char kbuf[sizeof(*frame) + 8]; |
84 | struct iwmmxt_sigframe *kframe; | |
1da177e4 LT |
85 | |
86 | /* the iWMMXt context must be 64 bit aligned */ | |
69b04754 | 87 | kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); |
85fe0681 DJ |
88 | kframe->magic = IWMMXT_MAGIC; |
89 | kframe->size = IWMMXT_STORAGE_SIZE; | |
69b04754 HD |
90 | iwmmxt_task_copy(current_thread_info(), &kframe->storage); |
91 | return __copy_to_user(frame, kframe, sizeof(*frame)); | |
1da177e4 LT |
92 | } |
93 | ||
94 | static int restore_iwmmxt_context(struct iwmmxt_sigframe *frame) | |
95 | { | |
69b04754 HD |
96 | char kbuf[sizeof(*frame) + 8]; |
97 | struct iwmmxt_sigframe *kframe; | |
98 | ||
99 | /* the iWMMXt context must be 64 bit aligned */ | |
100 | kframe = (struct iwmmxt_sigframe *)((unsigned long)(kbuf + 8) & ~7); | |
101 | if (__copy_from_user(kframe, frame, sizeof(*frame))) | |
102 | return -1; | |
85fe0681 DJ |
103 | if (kframe->magic != IWMMXT_MAGIC || |
104 | kframe->size != IWMMXT_STORAGE_SIZE) | |
69b04754 HD |
105 | return -1; |
106 | iwmmxt_task_restore(current_thread_info(), &kframe->storage); | |
107 | return 0; | |
1da177e4 LT |
108 | } |
109 | ||
110 | #endif | |
111 | ||
82c6f5a5 ID |
112 | #ifdef CONFIG_VFP |
113 | ||
114 | static int preserve_vfp_context(struct vfp_sigframe __user *frame) | |
115 | { | |
82c6f5a5 ID |
116 | const unsigned long magic = VFP_MAGIC; |
117 | const unsigned long size = VFP_STORAGE_SIZE; | |
118 | int err = 0; | |
119 | ||
82c6f5a5 ID |
120 | __put_user_error(magic, &frame->magic, err); |
121 | __put_user_error(size, &frame->size, err); | |
122 | ||
2498814f WD |
123 | if (err) |
124 | return -EFAULT; | |
125 | ||
126 | return vfp_preserve_user_clear_hwstate(&frame->ufp, &frame->ufp_exc); | |
82c6f5a5 ID |
127 | } |
128 | ||
129 | static int restore_vfp_context(struct vfp_sigframe __user *frame) | |
130 | { | |
82c6f5a5 ID |
131 | unsigned long magic; |
132 | unsigned long size; | |
82c6f5a5 ID |
133 | int err = 0; |
134 | ||
135 | __get_user_error(magic, &frame->magic, err); | |
136 | __get_user_error(size, &frame->size, err); | |
137 | ||
138 | if (err) | |
139 | return -EFAULT; | |
140 | if (magic != VFP_MAGIC || size != VFP_STORAGE_SIZE) | |
141 | return -EINVAL; | |
142 | ||
2498814f | 143 | return vfp_restore_user_hwstate(&frame->ufp, &frame->ufp_exc); |
82c6f5a5 ID |
144 | } |
145 | ||
146 | #endif | |
147 | ||
1da177e4 LT |
148 | /* |
149 | * Do a signal return; undo the signal stack. These are aligned to 64-bit. | |
150 | */ | |
151 | struct sigframe { | |
7d4fdc19 | 152 | struct ucontext uc; |
fcca538b | 153 | unsigned long retcode[2]; |
1da177e4 LT |
154 | }; |
155 | ||
156 | struct rt_sigframe { | |
1da177e4 | 157 | struct siginfo info; |
cb3504e8 | 158 | struct sigframe sig; |
1da177e4 LT |
159 | }; |
160 | ||
68071484 | 161 | static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf) |
1da177e4 | 162 | { |
85fe0681 | 163 | struct aux_sigframe __user *aux; |
68071484 RK |
164 | sigset_t set; |
165 | int err; | |
166 | ||
167 | err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set)); | |
77097ae5 | 168 | if (err == 0) |
101d9b0d | 169 | set_current_blocked(&set); |
1da177e4 | 170 | |
68071484 RK |
171 | __get_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err); |
172 | __get_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err); | |
173 | __get_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err); | |
174 | __get_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err); | |
175 | __get_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err); | |
176 | __get_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err); | |
177 | __get_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err); | |
178 | __get_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err); | |
179 | __get_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err); | |
180 | __get_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err); | |
181 | __get_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err); | |
182 | __get_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err); | |
183 | __get_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err); | |
184 | __get_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err); | |
185 | __get_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err); | |
186 | __get_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err); | |
187 | __get_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err); | |
1da177e4 LT |
188 | |
189 | err |= !valid_user_regs(regs); | |
190 | ||
85fe0681 | 191 | aux = (struct aux_sigframe __user *) sf->uc.uc_regspace; |
3bec6ded LB |
192 | #ifdef CONFIG_CRUNCH |
193 | if (err == 0) | |
194 | err |= restore_crunch_context(&aux->crunch); | |
195 | #endif | |
1da177e4 LT |
196 | #ifdef CONFIG_IWMMXT |
197 | if (err == 0 && test_thread_flag(TIF_USING_IWMMXT)) | |
198 | err |= restore_iwmmxt_context(&aux->iwmmxt); | |
199 | #endif | |
200 | #ifdef CONFIG_VFP | |
82c6f5a5 ID |
201 | if (err == 0) |
202 | err |= restore_vfp_context(&aux->vfp); | |
1da177e4 LT |
203 | #endif |
204 | ||
205 | return err; | |
206 | } | |
207 | ||
208 | asmlinkage int sys_sigreturn(struct pt_regs *regs) | |
209 | { | |
210 | struct sigframe __user *frame; | |
1da177e4 LT |
211 | |
212 | /* Always make any pending restarted system calls return -EINTR */ | |
213 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
214 | ||
215 | /* | |
216 | * Since we stacked the signal on a 64-bit boundary, | |
217 | * then 'sp' should be word aligned here. If it's | |
218 | * not, then the user is trying to mess with us. | |
219 | */ | |
220 | if (regs->ARM_sp & 7) | |
221 | goto badframe; | |
222 | ||
223 | frame = (struct sigframe __user *)regs->ARM_sp; | |
224 | ||
225 | if (!access_ok(VERIFY_READ, frame, sizeof (*frame))) | |
226 | goto badframe; | |
1da177e4 | 227 | |
68071484 | 228 | if (restore_sigframe(regs, frame)) |
1da177e4 LT |
229 | goto badframe; |
230 | ||
1da177e4 LT |
231 | return regs->ARM_r0; |
232 | ||
233 | badframe: | |
234 | force_sig(SIGSEGV, current); | |
235 | return 0; | |
236 | } | |
237 | ||
238 | asmlinkage int sys_rt_sigreturn(struct pt_regs *regs) | |
239 | { | |
240 | struct rt_sigframe __user *frame; | |
1da177e4 LT |
241 | |
242 | /* Always make any pending restarted system calls return -EINTR */ | |
243 | current_thread_info()->restart_block.fn = do_no_restart_syscall; | |
244 | ||
245 | /* | |
246 | * Since we stacked the signal on a 64-bit boundary, | |
247 | * then 'sp' should be word aligned here. If it's | |
248 | * not, then the user is trying to mess with us. | |
249 | */ | |
250 | if (regs->ARM_sp & 7) | |
251 | goto badframe; | |
252 | ||
253 | frame = (struct rt_sigframe __user *)regs->ARM_sp; | |
254 | ||
255 | if (!access_ok(VERIFY_READ, frame, sizeof (*frame))) | |
256 | goto badframe; | |
1da177e4 | 257 | |
68071484 | 258 | if (restore_sigframe(regs, &frame->sig)) |
1da177e4 LT |
259 | goto badframe; |
260 | ||
ec93ac86 | 261 | if (restore_altstack(&frame->sig.uc.uc_stack)) |
1da177e4 LT |
262 | goto badframe; |
263 | ||
1da177e4 LT |
264 | return regs->ARM_r0; |
265 | ||
266 | badframe: | |
267 | force_sig(SIGSEGV, current); | |
268 | return 0; | |
269 | } | |
270 | ||
271 | static int | |
aca6ca10 | 272 | setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs, sigset_t *set) |
1da177e4 | 273 | { |
85fe0681 | 274 | struct aux_sigframe __user *aux; |
1da177e4 LT |
275 | int err = 0; |
276 | ||
aca6ca10 RK |
277 | __put_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err); |
278 | __put_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err); | |
279 | __put_user_error(regs->ARM_r2, &sf->uc.uc_mcontext.arm_r2, err); | |
280 | __put_user_error(regs->ARM_r3, &sf->uc.uc_mcontext.arm_r3, err); | |
281 | __put_user_error(regs->ARM_r4, &sf->uc.uc_mcontext.arm_r4, err); | |
282 | __put_user_error(regs->ARM_r5, &sf->uc.uc_mcontext.arm_r5, err); | |
283 | __put_user_error(regs->ARM_r6, &sf->uc.uc_mcontext.arm_r6, err); | |
284 | __put_user_error(regs->ARM_r7, &sf->uc.uc_mcontext.arm_r7, err); | |
285 | __put_user_error(regs->ARM_r8, &sf->uc.uc_mcontext.arm_r8, err); | |
286 | __put_user_error(regs->ARM_r9, &sf->uc.uc_mcontext.arm_r9, err); | |
287 | __put_user_error(regs->ARM_r10, &sf->uc.uc_mcontext.arm_r10, err); | |
288 | __put_user_error(regs->ARM_fp, &sf->uc.uc_mcontext.arm_fp, err); | |
289 | __put_user_error(regs->ARM_ip, &sf->uc.uc_mcontext.arm_ip, err); | |
290 | __put_user_error(regs->ARM_sp, &sf->uc.uc_mcontext.arm_sp, err); | |
291 | __put_user_error(regs->ARM_lr, &sf->uc.uc_mcontext.arm_lr, err); | |
292 | __put_user_error(regs->ARM_pc, &sf->uc.uc_mcontext.arm_pc, err); | |
293 | __put_user_error(regs->ARM_cpsr, &sf->uc.uc_mcontext.arm_cpsr, err); | |
294 | ||
295 | __put_user_error(current->thread.trap_no, &sf->uc.uc_mcontext.trap_no, err); | |
296 | __put_user_error(current->thread.error_code, &sf->uc.uc_mcontext.error_code, err); | |
297 | __put_user_error(current->thread.address, &sf->uc.uc_mcontext.fault_address, err); | |
298 | __put_user_error(set->sig[0], &sf->uc.uc_mcontext.oldmask, err); | |
299 | ||
300 | err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set)); | |
1da177e4 | 301 | |
85fe0681 | 302 | aux = (struct aux_sigframe __user *) sf->uc.uc_regspace; |
3bec6ded LB |
303 | #ifdef CONFIG_CRUNCH |
304 | if (err == 0) | |
305 | err |= preserve_crunch_context(&aux->crunch); | |
306 | #endif | |
1da177e4 LT |
307 | #ifdef CONFIG_IWMMXT |
308 | if (err == 0 && test_thread_flag(TIF_USING_IWMMXT)) | |
309 | err |= preserve_iwmmxt_context(&aux->iwmmxt); | |
310 | #endif | |
311 | #ifdef CONFIG_VFP | |
82c6f5a5 ID |
312 | if (err == 0) |
313 | err |= preserve_vfp_context(&aux->vfp); | |
1da177e4 | 314 | #endif |
85fe0681 | 315 | __put_user_error(0, &aux->end_magic, err); |
1da177e4 LT |
316 | |
317 | return err; | |
318 | } | |
319 | ||
320 | static inline void __user * | |
7e243643 | 321 | get_sigframe(struct ksignal *ksig, struct pt_regs *regs, int framesize) |
1da177e4 | 322 | { |
7e243643 | 323 | unsigned long sp = sigsp(regs->ARM_sp, ksig); |
1da177e4 LT |
324 | void __user *frame; |
325 | ||
1da177e4 LT |
326 | /* |
327 | * ATPCS B01 mandates 8-byte alignment | |
328 | */ | |
329 | frame = (void __user *)((sp - framesize) & ~7); | |
330 | ||
331 | /* | |
332 | * Check that we can actually write to the signal frame. | |
333 | */ | |
334 | if (!access_ok(VERIFY_WRITE, frame, framesize)) | |
335 | frame = NULL; | |
336 | ||
337 | return frame; | |
338 | } | |
339 | ||
7e243643 AV |
340 | /* |
341 | * translate the signal | |
342 | */ | |
343 | static inline int map_sig(int sig) | |
344 | { | |
345 | struct thread_info *thread = current_thread_info(); | |
346 | if (sig < 32 && thread->exec_domain && thread->exec_domain->signal_invmap) | |
347 | sig = thread->exec_domain->signal_invmap[sig]; | |
348 | return sig; | |
349 | } | |
350 | ||
1da177e4 | 351 | static int |
7e243643 AV |
352 | setup_return(struct pt_regs *regs, struct ksignal *ksig, |
353 | unsigned long __user *rc, void __user *frame) | |
1da177e4 | 354 | { |
7e243643 | 355 | unsigned long handler = (unsigned long)ksig->ka.sa.sa_handler; |
1da177e4 LT |
356 | unsigned long retcode; |
357 | int thumb = 0; | |
53399053 RK |
358 | unsigned long cpsr = regs->ARM_cpsr & ~(PSR_f | PSR_E_BIT); |
359 | ||
360 | cpsr |= PSR_ENDSTATE; | |
1da177e4 LT |
361 | |
362 | /* | |
363 | * Maybe we need to deliver a 32-bit signal to a 26-bit task. | |
364 | */ | |
7e243643 | 365 | if (ksig->ka.sa.sa_flags & SA_THIRTYTWO) |
1da177e4 LT |
366 | cpsr = (cpsr & ~MODE_MASK) | USR_MODE; |
367 | ||
368 | #ifdef CONFIG_ARM_THUMB | |
369 | if (elf_hwcap & HWCAP_THUMB) { | |
370 | /* | |
371 | * The LSB of the handler determines if we're going to | |
372 | * be using THUMB or ARM mode for this signal handler. | |
373 | */ | |
374 | thumb = handler & 1; | |
375 | ||
d71e1352 | 376 | if (thumb) { |
1da177e4 | 377 | cpsr |= PSR_T_BIT; |
d71e1352 CM |
378 | #if __LINUX_ARM_ARCH__ >= 7 |
379 | /* clear the If-Then Thumb-2 execution state */ | |
380 | cpsr &= ~PSR_IT_MASK; | |
381 | #endif | |
382 | } else | |
1da177e4 LT |
383 | cpsr &= ~PSR_T_BIT; |
384 | } | |
385 | #endif | |
386 | ||
7e243643 AV |
387 | if (ksig->ka.sa.sa_flags & SA_RESTORER) { |
388 | retcode = (unsigned long)ksig->ka.sa.sa_restorer; | |
1da177e4 | 389 | } else { |
fcca538b | 390 | unsigned int idx = thumb << 1; |
1da177e4 | 391 | |
7e243643 | 392 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) |
fcca538b | 393 | idx += 3; |
1da177e4 | 394 | |
fcca538b NP |
395 | if (__put_user(sigreturn_codes[idx], rc) || |
396 | __put_user(sigreturn_codes[idx+1], rc+1)) | |
1da177e4 LT |
397 | return 1; |
398 | ||
e00d349e RK |
399 | if (cpsr & MODE32_BIT) { |
400 | /* | |
401 | * 32-bit code can use the new high-page | |
402 | * signal return code support. | |
403 | */ | |
404 | retcode = KERN_SIGRETURN_CODE + (idx << 2) + thumb; | |
405 | } else { | |
406 | /* | |
407 | * Ensure that the instruction cache sees | |
408 | * the return code written onto the stack. | |
409 | */ | |
410 | flush_icache_range((unsigned long)rc, | |
fcca538b | 411 | (unsigned long)(rc + 2)); |
e00d349e RK |
412 | |
413 | retcode = ((unsigned long)rc) + thumb; | |
414 | } | |
1da177e4 LT |
415 | } |
416 | ||
7e243643 | 417 | regs->ARM_r0 = map_sig(ksig->sig); |
1da177e4 LT |
418 | regs->ARM_sp = (unsigned long)frame; |
419 | regs->ARM_lr = retcode; | |
420 | regs->ARM_pc = handler; | |
421 | regs->ARM_cpsr = cpsr; | |
422 | ||
423 | return 0; | |
424 | } | |
425 | ||
426 | static int | |
7e243643 | 427 | setup_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) |
1da177e4 | 428 | { |
7e243643 | 429 | struct sigframe __user *frame = get_sigframe(ksig, regs, sizeof(*frame)); |
1da177e4 LT |
430 | int err = 0; |
431 | ||
432 | if (!frame) | |
433 | return 1; | |
434 | ||
ca195cfe RK |
435 | /* |
436 | * Set uc.uc_flags to a value which sc.trap_no would never have. | |
437 | */ | |
438 | __put_user_error(0x5ac3c35a, &frame->uc.uc_flags, err); | |
1da177e4 | 439 | |
aca6ca10 | 440 | err |= setup_sigframe(frame, regs, set); |
1da177e4 | 441 | if (err == 0) |
7e243643 | 442 | err = setup_return(regs, ksig, frame->retcode, frame); |
1da177e4 LT |
443 | |
444 | return err; | |
445 | } | |
446 | ||
447 | static int | |
7e243643 | 448 | setup_rt_frame(struct ksignal *ksig, sigset_t *set, struct pt_regs *regs) |
1da177e4 | 449 | { |
7e243643 | 450 | struct rt_sigframe __user *frame = get_sigframe(ksig, regs, sizeof(*frame)); |
1da177e4 LT |
451 | int err = 0; |
452 | ||
453 | if (!frame) | |
454 | return 1; | |
455 | ||
7e243643 | 456 | err |= copy_siginfo_to_user(&frame->info, &ksig->info); |
1da177e4 | 457 | |
cb3504e8 RK |
458 | __put_user_error(0, &frame->sig.uc.uc_flags, err); |
459 | __put_user_error(NULL, &frame->sig.uc.uc_link, err); | |
1da177e4 | 460 | |
ec93ac86 | 461 | err |= __save_altstack(&frame->sig.uc.uc_stack, regs->ARM_sp); |
aca6ca10 | 462 | err |= setup_sigframe(&frame->sig, regs, set); |
1da177e4 | 463 | if (err == 0) |
7e243643 | 464 | err = setup_return(regs, ksig, frame->sig.retcode, frame); |
1da177e4 LT |
465 | |
466 | if (err == 0) { | |
467 | /* | |
468 | * For realtime signals we must also set the second and third | |
469 | * arguments for the signal handler. | |
470 | * -- Peter Maydell <pmaydell@chiark.greenend.org.uk> 2000-12-06 | |
471 | */ | |
472 | regs->ARM_r1 = (unsigned long)&frame->info; | |
cb3504e8 | 473 | regs->ARM_r2 = (unsigned long)&frame->sig.uc; |
1da177e4 LT |
474 | } |
475 | ||
476 | return err; | |
477 | } | |
478 | ||
1da177e4 LT |
479 | /* |
480 | * OK, we're invoking a handler | |
481 | */ | |
7e243643 | 482 | static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) |
1da177e4 | 483 | { |
b7f9a11a | 484 | sigset_t *oldset = sigmask_to_save(); |
1da177e4 LT |
485 | int ret; |
486 | ||
1da177e4 LT |
487 | /* |
488 | * Set up the stack frame | |
489 | */ | |
7e243643 AV |
490 | if (ksig->ka.sa.sa_flags & SA_SIGINFO) |
491 | ret = setup_rt_frame(ksig, oldset, regs); | |
1da177e4 | 492 | else |
7e243643 | 493 | ret = setup_frame(ksig, oldset, regs); |
1da177e4 LT |
494 | |
495 | /* | |
496 | * Check that the resulting registers are actually sane. | |
497 | */ | |
498 | ret |= !valid_user_regs(regs); | |
499 | ||
7e243643 | 500 | signal_setup_done(ret, ksig, 0); |
1da177e4 LT |
501 | } |
502 | ||
503 | /* | |
504 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
505 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
506 | * mistake. | |
507 | * | |
508 | * Note that we go through the signals twice: once to check the signals that | |
509 | * the kernel can handle, and then we build all the user-level signal handling | |
510 | * stack-frames in one go after that. | |
511 | */ | |
81783786 | 512 | static int do_signal(struct pt_regs *regs, int syscall) |
1da177e4 | 513 | { |
2af68df0 | 514 | unsigned int retval = 0, continue_addr = 0, restart_addr = 0; |
7e243643 | 515 | struct ksignal ksig; |
81783786 | 516 | int restart = 0; |
1da177e4 | 517 | |
2af68df0 AB |
518 | /* |
519 | * If we were from a system call, check for system call restarting... | |
520 | */ | |
521 | if (syscall) { | |
522 | continue_addr = regs->ARM_pc; | |
523 | restart_addr = continue_addr - (thumb_mode(regs) ? 2 : 4); | |
524 | retval = regs->ARM_r0; | |
525 | ||
526 | /* | |
527 | * Prepare for system call restart. We do this here so that a | |
528 | * debugger will see the already changed PSW. | |
529 | */ | |
530 | switch (retval) { | |
81783786 | 531 | case -ERESTART_RESTARTBLOCK: |
66285217 | 532 | restart -= 2; |
2af68df0 AB |
533 | case -ERESTARTNOHAND: |
534 | case -ERESTARTSYS: | |
535 | case -ERESTARTNOINTR: | |
81783786 | 536 | restart++; |
2af68df0 AB |
537 | regs->ARM_r0 = regs->ARM_ORIG_r0; |
538 | regs->ARM_pc = restart_addr; | |
539 | break; | |
2af68df0 AB |
540 | } |
541 | } | |
542 | ||
2af68df0 AB |
543 | /* |
544 | * Get the signal to deliver. When running under ptrace, at this | |
545 | * point the debugger may change all our registers ... | |
546 | */ | |
81783786 AV |
547 | /* |
548 | * Depending on the signal settings we may need to revert the | |
549 | * decision to restart the system call. But skip this if a | |
550 | * debugger has chosen to restart at a different PC. | |
551 | */ | |
7e243643 AV |
552 | if (get_signal(&ksig)) { |
553 | /* handler */ | |
554 | if (unlikely(restart) && regs->ARM_pc == restart_addr) { | |
ad82cc08 WD |
555 | if (retval == -ERESTARTNOHAND || |
556 | retval == -ERESTART_RESTARTBLOCK | |
2af68df0 | 557 | || (retval == -ERESTARTSYS |
7e243643 | 558 | && !(ksig.ka.sa.sa_flags & SA_RESTART))) { |
2af68df0 AB |
559 | regs->ARM_r0 = -EINTR; |
560 | regs->ARM_pc = continue_addr; | |
561 | } | |
562 | } | |
7e243643 AV |
563 | handle_signal(&ksig, regs); |
564 | } else { | |
565 | /* no handler */ | |
566 | restore_saved_sigmask(); | |
567 | if (unlikely(restart) && regs->ARM_pc == restart_addr) { | |
568 | regs->ARM_pc = continue_addr; | |
569 | return restart; | |
570 | } | |
1da177e4 | 571 | } |
7e243643 | 572 | return 0; |
1da177e4 LT |
573 | } |
574 | ||
81783786 | 575 | asmlinkage int |
0a267fa6 | 576 | do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall) |
1da177e4 | 577 | { |
0a267fa6 AV |
578 | do { |
579 | if (likely(thread_flags & _TIF_NEED_RESCHED)) { | |
580 | schedule(); | |
581 | } else { | |
582 | if (unlikely(!user_mode(regs))) | |
81783786 | 583 | return 0; |
0a267fa6 AV |
584 | local_irq_enable(); |
585 | if (thread_flags & _TIF_SIGPENDING) { | |
66285217 AV |
586 | int restart = do_signal(regs, syscall); |
587 | if (unlikely(restart)) { | |
81783786 AV |
588 | /* |
589 | * Restart without handlers. | |
590 | * Deal with it without leaving | |
591 | * the kernel space. | |
592 | */ | |
66285217 | 593 | return restart; |
81783786 | 594 | } |
0a267fa6 AV |
595 | syscall = 0; |
596 | } else { | |
597 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
598 | tracehook_notify_resume(regs); | |
599 | } | |
600 | } | |
601 | local_irq_disable(); | |
602 | thread_flags = current_thread_info()->flags; | |
603 | } while (thread_flags & _TIF_WORK_MASK); | |
81783786 | 604 | return 0; |
1da177e4 | 605 | } |