Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * linux/arch/parisc/kernel/signal.c: Architecture-specific signal | |
3 | * handling support. | |
4 | * | |
5 | * Copyright (C) 2000 David Huggins-Daines <dhd@debian.org> | |
6 | * Copyright (C) 2000 Linuxcare, Inc. | |
7 | * | |
8 | * Based on the ia64, i386, and alpha versions. | |
9 | * | |
10 | * Like the IA-64, we are a recent enough port (we are *starting* | |
11 | * with glibc2.2) that we do not need to support the old non-realtime | |
12 | * Linux signals. Therefore we don't. HP/UX signals will go in | |
13 | * arch/parisc/hpux/signal.c when we figure out how to do them. | |
14 | */ | |
15 | ||
16 | #include <linux/sched.h> | |
17 | #include <linux/mm.h> | |
18 | #include <linux/smp.h> | |
1da177e4 LT |
19 | #include <linux/kernel.h> |
20 | #include <linux/signal.h> | |
21 | #include <linux/errno.h> | |
22 | #include <linux/wait.h> | |
23 | #include <linux/ptrace.h> | |
ecf02de5 | 24 | #include <linux/tracehook.h> |
1da177e4 LT |
25 | #include <linux/unistd.h> |
26 | #include <linux/stddef.h> | |
27 | #include <linux/compat.h> | |
28 | #include <linux/elf.h> | |
1da177e4 LT |
29 | #include <asm/ucontext.h> |
30 | #include <asm/rt_sigframe.h> | |
31 | #include <asm/uaccess.h> | |
32 | #include <asm/pgalloc.h> | |
33 | #include <asm/cacheflush.h> | |
0013a854 | 34 | #include <asm/asm-offsets.h> |
1da177e4 LT |
35 | |
36 | #ifdef CONFIG_COMPAT | |
1da177e4 LT |
37 | #include "signal32.h" |
38 | #endif | |
39 | ||
40 | #define DEBUG_SIG 0 | |
41 | #define DEBUG_SIG_LEVEL 2 | |
42 | ||
43 | #if DEBUG_SIG | |
44 | #define DBG(LEVEL, ...) \ | |
45 | ((DEBUG_SIG_LEVEL >= LEVEL) \ | |
46 | ? printk(__VA_ARGS__) : (void) 0) | |
47 | #else | |
48 | #define DBG(LEVEL, ...) | |
49 | #endif | |
50 | ||
51 | ||
52 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) | |
53 | ||
54 | /* gcc will complain if a pointer is cast to an integer of different | |
55 | * size. If you really need to do this (and we do for an ELF32 user | |
56 | * application in an ELF64 kernel) then you have to do a cast to an | |
57 | * integer of the same size first. The A() macro accomplishes | |
58 | * this. */ | |
59 | #define A(__x) ((unsigned long)(__x)) | |
60 | ||
1da177e4 LT |
61 | /* |
62 | * Atomically swap in the new signal mask, and wait for a signal. | |
63 | */ | |
a8f44e38 | 64 | #ifdef CONFIG_64BIT |
1da177e4 LT |
65 | #include "sys32.h" |
66 | #endif | |
67 | ||
1da177e4 LT |
68 | /* |
69 | * Do a signal return - restore sigcontext. | |
70 | */ | |
71 | ||
72 | /* Trampoline for calling rt_sigreturn() */ | |
73 | #define INSN_LDI_R25_0 0x34190000 /* ldi 0,%r25 (in_syscall=0) */ | |
74 | #define INSN_LDI_R25_1 0x34190002 /* ldi 1,%r25 (in_syscall=1) */ | |
75 | #define INSN_LDI_R20 0x3414015a /* ldi __NR_rt_sigreturn,%r20 */ | |
76 | #define INSN_BLE_SR2_R0 0xe4008200 /* be,l 0x100(%sr2,%r0),%sr0,%r31 */ | |
77 | #define INSN_NOP 0x08000240 /* nop */ | |
78 | /* For debugging */ | |
79 | #define INSN_DIE_HORRIBLY 0x68000ccc /* stw %r0,0x666(%sr0,%r0) */ | |
80 | ||
81 | static long | |
82 | restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs) | |
83 | { | |
84 | long err = 0; | |
85 | ||
86 | err |= __copy_from_user(regs->gr, sc->sc_gr, sizeof(regs->gr)); | |
87 | err |= __copy_from_user(regs->fr, sc->sc_fr, sizeof(regs->fr)); | |
88 | err |= __copy_from_user(regs->iaoq, sc->sc_iaoq, sizeof(regs->iaoq)); | |
89 | err |= __copy_from_user(regs->iasq, sc->sc_iasq, sizeof(regs->iasq)); | |
90 | err |= __get_user(regs->sar, &sc->sc_sar); | |
91 | DBG(2,"restore_sigcontext: iaoq is 0x%#lx / 0x%#lx\n", | |
92 | regs->iaoq[0],regs->iaoq[1]); | |
93 | DBG(2,"restore_sigcontext: r28 is %ld\n", regs->gr[28]); | |
94 | return err; | |
95 | } | |
96 | ||
97 | void | |
98 | sys_rt_sigreturn(struct pt_regs *regs, int in_syscall) | |
99 | { | |
100 | struct rt_sigframe __user *frame; | |
1da177e4 LT |
101 | sigset_t set; |
102 | unsigned long usp = (regs->gr[30] & ~(0x01UL)); | |
103 | unsigned long sigframe_size = PARISC_RT_SIGFRAME_SIZE; | |
a8f44e38 | 104 | #ifdef CONFIG_64BIT |
1da177e4 LT |
105 | compat_sigset_t compat_set; |
106 | struct compat_rt_sigframe __user * compat_frame; | |
107 | ||
a3ea84fa | 108 | if (is_compat_task()) |
1da177e4 LT |
109 | sigframe_size = PARISC_RT_SIGFRAME_SIZE32; |
110 | #endif | |
111 | ||
85a847ff | 112 | current_thread_info()->restart_block.fn = do_no_restart_syscall; |
1da177e4 LT |
113 | |
114 | /* Unwind the user stack to get the rt_sigframe structure. */ | |
115 | frame = (struct rt_sigframe __user *) | |
116 | (usp - sigframe_size); | |
117 | DBG(2,"sys_rt_sigreturn: frame is %p\n", frame); | |
118 | ||
a8f44e38 | 119 | #ifdef CONFIG_64BIT |
1da177e4 LT |
120 | compat_frame = (struct compat_rt_sigframe __user *)frame; |
121 | ||
a3ea84fa | 122 | if (is_compat_task()) { |
1da177e4 LT |
123 | DBG(2,"sys_rt_sigreturn: ELF32 process.\n"); |
124 | if (__copy_from_user(&compat_set, &compat_frame->uc.uc_sigmask, sizeof(compat_set))) | |
125 | goto give_sigsegv; | |
126 | sigset_32to64(&set,&compat_set); | |
127 | } else | |
128 | #endif | |
129 | { | |
130 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) | |
131 | goto give_sigsegv; | |
132 | } | |
133 | ||
134 | sigdelsetmask(&set, ~_BLOCKABLE); | |
ade7728b | 135 | set_current_blocked(&set); |
1da177e4 LT |
136 | |
137 | /* Good thing we saved the old gr[30], eh? */ | |
a8f44e38 | 138 | #ifdef CONFIG_64BIT |
a3ea84fa | 139 | if (is_compat_task()) { |
1da177e4 LT |
140 | DBG(1,"sys_rt_sigreturn: compat_frame->uc.uc_mcontext 0x%p\n", |
141 | &compat_frame->uc.uc_mcontext); | |
142 | // FIXME: Load upper half from register file | |
143 | if (restore_sigcontext32(&compat_frame->uc.uc_mcontext, | |
144 | &compat_frame->regs, regs)) | |
145 | goto give_sigsegv; | |
146 | DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n", | |
147 | usp, &compat_frame->uc.uc_stack); | |
148 | if (do_sigaltstack32(&compat_frame->uc.uc_stack, NULL, usp) == -EFAULT) | |
149 | goto give_sigsegv; | |
150 | } else | |
151 | #endif | |
152 | { | |
153 | DBG(1,"sys_rt_sigreturn: frame->uc.uc_mcontext 0x%p\n", | |
154 | &frame->uc.uc_mcontext); | |
155 | if (restore_sigcontext(&frame->uc.uc_mcontext, regs)) | |
156 | goto give_sigsegv; | |
157 | DBG(1,"sys_rt_sigreturn: usp %#08lx stack 0x%p\n", | |
158 | usp, &frame->uc.uc_stack); | |
159 | if (do_sigaltstack(&frame->uc.uc_stack, NULL, usp) == -EFAULT) | |
160 | goto give_sigsegv; | |
161 | } | |
162 | ||
163 | ||
164 | ||
165 | /* If we are on the syscall path IAOQ will not be restored, and | |
166 | * if we are on the interrupt path we must not corrupt gr31. | |
167 | */ | |
168 | if (in_syscall) | |
169 | regs->gr[31] = regs->iaoq[0]; | |
170 | #if DEBUG_SIG | |
171 | DBG(1,"sys_rt_sigreturn: returning to %#lx, DUMPING REGS:\n", regs->iaoq[0]); | |
172 | show_regs(regs); | |
173 | #endif | |
174 | return; | |
175 | ||
176 | give_sigsegv: | |
177 | DBG(1,"sys_rt_sigreturn: Sending SIGSEGV\n"); | |
67bace72 | 178 | force_sig(SIGSEGV, current); |
1da177e4 LT |
179 | return; |
180 | } | |
181 | ||
182 | /* | |
183 | * Set up a signal frame. | |
184 | */ | |
185 | ||
186 | static inline void __user * | |
187 | get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size) | |
188 | { | |
189 | /*FIXME: ELF32 vs. ELF64 has different frame_size, but since we | |
190 | don't use the parameter it doesn't matter */ | |
191 | ||
192 | DBG(1,"get_sigframe: ka = %#lx, sp = %#lx, frame_size = %#lx\n", | |
193 | (unsigned long)ka, sp, frame_size); | |
194 | ||
d09042da | 195 | if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp)) |
1da177e4 LT |
196 | sp = current->sas_ss_sp; /* Stacks grow up! */ |
197 | ||
198 | DBG(1,"get_sigframe: Returning sp = %#lx\n", (unsigned long)sp); | |
199 | return (void __user *) sp; /* Stacks grow up. Fun. */ | |
200 | } | |
201 | ||
202 | static long | |
203 | setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, int in_syscall) | |
204 | ||
205 | { | |
206 | unsigned long flags = 0; | |
207 | long err = 0; | |
208 | ||
209 | if (on_sig_stack((unsigned long) sc)) | |
210 | flags |= PARISC_SC_FLAG_ONSTACK; | |
211 | if (in_syscall) { | |
212 | flags |= PARISC_SC_FLAG_IN_SYSCALL; | |
213 | /* regs->iaoq is undefined in the syscall return path */ | |
214 | err |= __put_user(regs->gr[31], &sc->sc_iaoq[0]); | |
215 | err |= __put_user(regs->gr[31]+4, &sc->sc_iaoq[1]); | |
216 | err |= __put_user(regs->sr[3], &sc->sc_iasq[0]); | |
217 | err |= __put_user(regs->sr[3], &sc->sc_iasq[1]); | |
218 | DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (in syscall)\n", | |
219 | regs->gr[31], regs->gr[31]+4); | |
220 | } else { | |
221 | err |= __copy_to_user(sc->sc_iaoq, regs->iaoq, sizeof(regs->iaoq)); | |
222 | err |= __copy_to_user(sc->sc_iasq, regs->iasq, sizeof(regs->iasq)); | |
223 | DBG(1,"setup_sigcontext: iaoq %#lx / %#lx (not in syscall)\n", | |
224 | regs->iaoq[0], regs->iaoq[1]); | |
225 | } | |
226 | ||
227 | err |= __put_user(flags, &sc->sc_flags); | |
228 | err |= __copy_to_user(sc->sc_gr, regs->gr, sizeof(regs->gr)); | |
229 | err |= __copy_to_user(sc->sc_fr, regs->fr, sizeof(regs->fr)); | |
230 | err |= __put_user(regs->sar, &sc->sc_sar); | |
231 | DBG(1,"setup_sigcontext: r28 is %ld\n", regs->gr[28]); | |
232 | ||
233 | return err; | |
234 | } | |
235 | ||
236 | static long | |
237 | setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, | |
238 | sigset_t *set, struct pt_regs *regs, int in_syscall) | |
239 | { | |
240 | struct rt_sigframe __user *frame; | |
241 | unsigned long rp, usp; | |
242 | unsigned long haddr, sigframe_size; | |
1da177e4 | 243 | int err = 0; |
a8f44e38 | 244 | #ifdef CONFIG_64BIT |
1da177e4 LT |
245 | compat_int_t compat_val; |
246 | struct compat_rt_sigframe __user * compat_frame; | |
247 | compat_sigset_t compat_set; | |
248 | #endif | |
249 | ||
250 | usp = (regs->gr[30] & ~(0x01UL)); | |
251 | /*FIXME: frame_size parameter is unused, remove it. */ | |
252 | frame = get_sigframe(ka, usp, sizeof(*frame)); | |
253 | ||
254 | DBG(1,"SETUP_RT_FRAME: START\n"); | |
255 | DBG(1,"setup_rt_frame: frame %p info %p\n", frame, info); | |
256 | ||
257 | ||
a8f44e38 | 258 | #ifdef CONFIG_64BIT |
1da177e4 LT |
259 | |
260 | compat_frame = (struct compat_rt_sigframe __user *)frame; | |
261 | ||
a3ea84fa | 262 | if (is_compat_task()) { |
1da177e4 | 263 | DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &compat_frame->info); |
f671c45d | 264 | err |= copy_siginfo_to_user32(&compat_frame->info, info); |
1da177e4 LT |
265 | DBG(1,"SETUP_RT_FRAME: 1\n"); |
266 | compat_val = (compat_int_t)current->sas_ss_sp; | |
267 | err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_sp); | |
268 | DBG(1,"SETUP_RT_FRAME: 2\n"); | |
269 | compat_val = (compat_int_t)current->sas_ss_size; | |
270 | err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_size); | |
271 | DBG(1,"SETUP_RT_FRAME: 3\n"); | |
272 | compat_val = sas_ss_flags(regs->gr[30]); | |
273 | err |= __put_user(compat_val, &compat_frame->uc.uc_stack.ss_flags); | |
274 | DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &compat_frame->uc); | |
275 | DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &compat_frame->uc.uc_mcontext); | |
276 | err |= setup_sigcontext32(&compat_frame->uc.uc_mcontext, | |
277 | &compat_frame->regs, regs, in_syscall); | |
278 | sigset_64to32(&compat_set,set); | |
279 | err |= __copy_to_user(&compat_frame->uc.uc_sigmask, &compat_set, sizeof(compat_set)); | |
280 | } else | |
281 | #endif | |
282 | { | |
283 | DBG(1,"setup_rt_frame: frame->info = 0x%p\n", &frame->info); | |
284 | err |= copy_siginfo_to_user(&frame->info, info); | |
285 | err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); | |
286 | err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); | |
287 | err |= __put_user(sas_ss_flags(regs->gr[30]), | |
288 | &frame->uc.uc_stack.ss_flags); | |
289 | DBG(1,"setup_rt_frame: frame->uc = 0x%p\n", &frame->uc); | |
290 | DBG(1,"setup_rt_frame: frame->uc.uc_mcontext = 0x%p\n", &frame->uc.uc_mcontext); | |
291 | err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, in_syscall); | |
25985edc | 292 | /* FIXME: Should probably be converted as well for the compat case */ |
1da177e4 LT |
293 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); |
294 | } | |
295 | ||
296 | if (err) | |
297 | goto give_sigsegv; | |
298 | ||
299 | /* Set up to return from userspace. If provided, use a stub | |
300 | already in userspace. The first words of tramp are used to | |
301 | save the previous sigrestartblock trampoline that might be | |
302 | on the stack. We start the sigreturn trampoline at | |
303 | SIGRESTARTBLOCK_TRAMP+X. */ | |
304 | err |= __put_user(in_syscall ? INSN_LDI_R25_1 : INSN_LDI_R25_0, | |
305 | &frame->tramp[SIGRESTARTBLOCK_TRAMP+0]); | |
306 | err |= __put_user(INSN_LDI_R20, | |
307 | &frame->tramp[SIGRESTARTBLOCK_TRAMP+1]); | |
308 | err |= __put_user(INSN_BLE_SR2_R0, | |
309 | &frame->tramp[SIGRESTARTBLOCK_TRAMP+2]); | |
310 | err |= __put_user(INSN_NOP, &frame->tramp[SIGRESTARTBLOCK_TRAMP+3]); | |
311 | ||
312 | #if DEBUG_SIG | |
313 | /* Assert that we're flushing in the correct space... */ | |
314 | { | |
315 | int sid; | |
316 | asm ("mfsp %%sr3,%0" : "=r" (sid)); | |
317 | DBG(1,"setup_rt_frame: Flushing 64 bytes at space %#x offset %p\n", | |
318 | sid, frame->tramp); | |
319 | } | |
320 | #endif | |
321 | ||
322 | flush_user_dcache_range((unsigned long) &frame->tramp[0], | |
323 | (unsigned long) &frame->tramp[TRAMP_SIZE]); | |
324 | flush_user_icache_range((unsigned long) &frame->tramp[0], | |
325 | (unsigned long) &frame->tramp[TRAMP_SIZE]); | |
326 | ||
efad798b | 327 | /* TRAMP Words 0-4, Length 5 = SIGRESTARTBLOCK_TRAMP |
1da177e4 LT |
328 | * TRAMP Words 5-9, Length 4 = SIGRETURN_TRAMP |
329 | * So the SIGRETURN_TRAMP is at the end of SIGRESTARTBLOCK_TRAMP | |
330 | */ | |
331 | rp = (unsigned long) &frame->tramp[SIGRESTARTBLOCK_TRAMP]; | |
332 | ||
333 | if (err) | |
334 | goto give_sigsegv; | |
335 | ||
336 | haddr = A(ka->sa.sa_handler); | |
337 | /* The sa_handler may be a pointer to a function descriptor */ | |
a8f44e38 | 338 | #ifdef CONFIG_64BIT |
a3ea84fa | 339 | if (is_compat_task()) { |
1da177e4 LT |
340 | #endif |
341 | if (haddr & PA_PLABEL_FDESC) { | |
342 | Elf32_Fdesc fdesc; | |
343 | Elf32_Fdesc __user *ufdesc = (Elf32_Fdesc __user *)A(haddr & ~3); | |
344 | ||
345 | err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc)); | |
346 | ||
347 | if (err) | |
348 | goto give_sigsegv; | |
349 | ||
350 | haddr = fdesc.addr; | |
351 | regs->gr[19] = fdesc.gp; | |
352 | } | |
a8f44e38 | 353 | #ifdef CONFIG_64BIT |
1da177e4 LT |
354 | } else { |
355 | Elf64_Fdesc fdesc; | |
356 | Elf64_Fdesc __user *ufdesc = (Elf64_Fdesc __user *)A(haddr & ~3); | |
357 | ||
358 | err = __copy_from_user(&fdesc, ufdesc, sizeof(fdesc)); | |
359 | ||
360 | if (err) | |
361 | goto give_sigsegv; | |
362 | ||
363 | haddr = fdesc.addr; | |
364 | regs->gr[19] = fdesc.gp; | |
365 | DBG(1,"setup_rt_frame: 64 bit signal, exe=%#lx, r19=%#lx, in_syscall=%d\n", | |
366 | haddr, regs->gr[19], in_syscall); | |
367 | } | |
368 | #endif | |
369 | ||
370 | /* The syscall return path will create IAOQ values from r31. | |
371 | */ | |
372 | sigframe_size = PARISC_RT_SIGFRAME_SIZE; | |
a8f44e38 | 373 | #ifdef CONFIG_64BIT |
a3ea84fa | 374 | if (is_compat_task()) |
1da177e4 LT |
375 | sigframe_size = PARISC_RT_SIGFRAME_SIZE32; |
376 | #endif | |
377 | if (in_syscall) { | |
378 | regs->gr[31] = haddr; | |
a8f44e38 | 379 | #ifdef CONFIG_64BIT |
df570b9c | 380 | if (!test_thread_flag(TIF_32BIT)) |
1da177e4 LT |
381 | sigframe_size |= 1; |
382 | #endif | |
383 | } else { | |
384 | unsigned long psw = USER_PSW; | |
a8f44e38 | 385 | #ifdef CONFIG_64BIT |
df570b9c | 386 | if (!test_thread_flag(TIF_32BIT)) |
1da177e4 LT |
387 | psw |= PSW_W; |
388 | #endif | |
389 | ||
390 | /* If we are singlestepping, arrange a trap to be delivered | |
391 | when we return to userspace. Note the semantics -- we | |
392 | should trap before the first insn in the handler is | |
393 | executed. Ref: | |
394 | http://sources.redhat.com/ml/gdb/2004-11/msg00245.html | |
395 | */ | |
396 | if (pa_psw(current)->r) { | |
397 | pa_psw(current)->r = 0; | |
398 | psw |= PSW_R; | |
399 | mtctl(-1, 0); | |
400 | } | |
401 | ||
402 | regs->gr[0] = psw; | |
403 | regs->iaoq[0] = haddr | 3; | |
404 | regs->iaoq[1] = regs->iaoq[0] + 4; | |
405 | } | |
406 | ||
407 | regs->gr[2] = rp; /* userland return pointer */ | |
408 | regs->gr[26] = sig; /* signal number */ | |
409 | ||
a8f44e38 | 410 | #ifdef CONFIG_64BIT |
a3ea84fa | 411 | if (is_compat_task()) { |
1da177e4 LT |
412 | regs->gr[25] = A(&compat_frame->info); /* siginfo pointer */ |
413 | regs->gr[24] = A(&compat_frame->uc); /* ucontext pointer */ | |
414 | } else | |
415 | #endif | |
416 | { | |
417 | regs->gr[25] = A(&frame->info); /* siginfo pointer */ | |
418 | regs->gr[24] = A(&frame->uc); /* ucontext pointer */ | |
419 | } | |
420 | ||
421 | DBG(1,"setup_rt_frame: making sigreturn frame: %#lx + %#lx = %#lx\n", | |
422 | regs->gr[30], sigframe_size, | |
423 | regs->gr[30] + sigframe_size); | |
424 | /* Raise the user stack pointer to make a proper call frame. */ | |
425 | regs->gr[30] = (A(frame) + sigframe_size); | |
426 | ||
427 | ||
428 | DBG(1,"setup_rt_frame: sig deliver (%s,%d) frame=0x%p sp=%#lx iaoq=%#lx/%#lx rp=%#lx\n", | |
429 | current->comm, current->pid, frame, regs->gr[30], | |
430 | regs->iaoq[0], regs->iaoq[1], rp); | |
431 | ||
432 | return 1; | |
433 | ||
434 | give_sigsegv: | |
435 | DBG(1,"setup_rt_frame: sending SIGSEGV\n"); | |
40c72f20 | 436 | force_sigsegv(sig, current); |
1da177e4 LT |
437 | return 0; |
438 | } | |
439 | ||
440 | /* | |
441 | * OK, we're invoking a handler. | |
442 | */ | |
443 | ||
444 | static long | |
445 | handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, | |
446 | sigset_t *oldset, struct pt_regs *regs, int in_syscall) | |
447 | { | |
448 | DBG(1,"handle_signal: sig=%ld, ka=%p, info=%p, oldset=%p, regs=%p\n", | |
449 | sig, ka, info, oldset, regs); | |
450 | ||
451 | /* Set up the stack frame */ | |
452 | if (!setup_rt_frame(sig, ka, info, oldset, regs, in_syscall)) | |
453 | return 0; | |
454 | ||
ade7728b | 455 | block_sigmask(ka, sig); |
ecf02de5 | 456 | |
22a8cdd6 KM |
457 | tracehook_signal_handler(sig, info, ka, regs, |
458 | test_thread_flag(TIF_SINGLESTEP) || | |
459 | test_thread_flag(TIF_BLOCKSTEP)); | |
ecf02de5 | 460 | |
1da177e4 LT |
461 | return 1; |
462 | } | |
463 | ||
2b163b71 KM |
464 | static inline void |
465 | syscall_restart(struct pt_regs *regs, struct k_sigaction *ka) | |
466 | { | |
467 | /* Check the return code */ | |
468 | switch (regs->gr[28]) { | |
469 | case -ERESTART_RESTARTBLOCK: | |
2b163b71 KM |
470 | case -ERESTARTNOHAND: |
471 | DBG(1,"ERESTARTNOHAND: returning -EINTR\n"); | |
472 | regs->gr[28] = -EINTR; | |
473 | break; | |
474 | ||
475 | case -ERESTARTSYS: | |
476 | if (!(ka->sa.sa_flags & SA_RESTART)) { | |
477 | DBG(1,"ERESTARTSYS: putting -EINTR\n"); | |
478 | regs->gr[28] = -EINTR; | |
479 | break; | |
480 | } | |
481 | /* fallthrough */ | |
482 | case -ERESTARTNOINTR: | |
483 | /* A syscall is just a branch, so all | |
484 | * we have to do is fiddle the return pointer. | |
485 | */ | |
486 | regs->gr[31] -= 8; /* delayed branching */ | |
487 | /* Preserve original r28. */ | |
488 | regs->gr[28] = regs->orig_r28; | |
489 | break; | |
490 | } | |
491 | } | |
492 | ||
493 | static inline void | |
494 | insert_restart_trampoline(struct pt_regs *regs) | |
495 | { | |
496 | switch(regs->gr[28]) { | |
497 | case -ERESTART_RESTARTBLOCK: { | |
498 | /* Restart the system call - no handlers present */ | |
499 | unsigned int *usp = (unsigned int *)regs->gr[30]; | |
500 | ||
501 | /* Setup a trampoline to restart the syscall | |
502 | * with __NR_restart_syscall | |
503 | * | |
504 | * 0: <return address (orig r31)> | |
505 | * 4: <2nd half for 64-bit> | |
506 | * 8: ldw 0(%sp), %r31 | |
507 | * 12: be 0x100(%sr2, %r0) | |
508 | * 16: ldi __NR_restart_syscall, %r20 | |
509 | */ | |
510 | #ifdef CONFIG_64BIT | |
511 | put_user(regs->gr[31] >> 32, &usp[0]); | |
512 | put_user(regs->gr[31] & 0xffffffff, &usp[1]); | |
513 | put_user(0x0fc010df, &usp[2]); | |
514 | #else | |
515 | put_user(regs->gr[31], &usp[0]); | |
516 | put_user(0x0fc0109f, &usp[2]); | |
517 | #endif | |
518 | put_user(0xe0008200, &usp[3]); | |
519 | put_user(0x34140000, &usp[4]); | |
520 | ||
521 | /* Stack is 64-byte aligned, and we only need | |
522 | * to flush 1 cache line. | |
523 | * Flushing one cacheline is cheap. | |
524 | * "sync" on bigger (> 4 way) boxes is not. | |
525 | */ | |
cf39cc3b KM |
526 | flush_user_dcache_range(regs->gr[30], regs->gr[30] + 4); |
527 | flush_user_icache_range(regs->gr[30], regs->gr[30] + 4); | |
2b163b71 KM |
528 | |
529 | regs->gr[31] = regs->gr[30] + 8; | |
530 | /* Preserve original r28. */ | |
531 | regs->gr[28] = regs->orig_r28; | |
532 | ||
533 | return; | |
534 | } | |
535 | case -ERESTARTNOHAND: | |
536 | case -ERESTARTSYS: | |
537 | case -ERESTARTNOINTR: { | |
538 | /* Hooray for delayed branching. We don't | |
539 | * have to restore %r20 (the system call | |
540 | * number) because it gets loaded in the delay | |
541 | * slot of the branch external instruction. | |
542 | */ | |
543 | regs->gr[31] -= 8; | |
544 | /* Preserve original r28. */ | |
545 | regs->gr[28] = regs->orig_r28; | |
546 | ||
547 | return; | |
548 | } | |
549 | default: | |
550 | break; | |
551 | } | |
552 | } | |
553 | ||
1da177e4 LT |
554 | /* |
555 | * Note that 'init' is a special process: it doesn't get signals it doesn't | |
556 | * want to handle. Thus you cannot kill init even with a SIGKILL even by | |
557 | * mistake. | |
558 | * | |
559 | * We need to be able to restore the syscall arguments (r21-r26) to | |
560 | * restart syscalls. Thus, the syscall path should save them in the | |
561 | * pt_regs structure (it's okay to do so since they are caller-save | |
562 | * registers). As noted below, the syscall number gets restored for | |
563 | * us due to the magic of delayed branching. | |
564 | */ | |
4650f0a5 KM |
565 | asmlinkage void |
566 | do_signal(struct pt_regs *regs, long in_syscall) | |
1da177e4 LT |
567 | { |
568 | siginfo_t info; | |
569 | struct k_sigaction ka; | |
570 | int signr; | |
4650f0a5 | 571 | sigset_t *oldset; |
1da177e4 LT |
572 | |
573 | DBG(1,"\ndo_signal: oldset=0x%p, regs=0x%p, sr7 %#lx, in_syscall=%d\n", | |
574 | oldset, regs, regs->sr[7], in_syscall); | |
575 | ||
576 | /* Everyone else checks to see if they are in kernel mode at | |
577 | this point and exits if that's the case. I'm not sure why | |
578 | we would be called in that case, but for some reason we | |
579 | are. */ | |
580 | ||
4650f0a5 KM |
581 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) |
582 | oldset = ¤t->saved_sigmask; | |
583 | else | |
1da177e4 LT |
584 | oldset = ¤t->blocked; |
585 | ||
586 | DBG(1,"do_signal: oldset %08lx / %08lx\n", | |
587 | oldset->sig[0], oldset->sig[1]); | |
588 | ||
589 | ||
590 | /* May need to force signal if handle_signal failed to deliver */ | |
591 | while (1) { | |
592 | ||
593 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); | |
594 | DBG(3,"do_signal: signr = %d, regs->gr[28] = %ld\n", signr, regs->gr[28]); | |
595 | ||
596 | if (signr <= 0) | |
597 | break; | |
598 | ||
599 | /* Restart a system call if necessary. */ | |
2b163b71 KM |
600 | if (in_syscall) |
601 | syscall_restart(regs, &ka); | |
602 | ||
1da177e4 LT |
603 | /* Whee! Actually deliver the signal. If the |
604 | delivery failed, we need to continue to iterate in | |
605 | this loop so we can deliver the SIGSEGV... */ | |
2b163b71 KM |
606 | if (handle_signal(signr, &info, &ka, oldset, |
607 | regs, in_syscall)) { | |
1da177e4 LT |
608 | DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n", |
609 | regs->gr[28]); | |
4650f0a5 KM |
610 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) |
611 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
612 | return; | |
1da177e4 LT |
613 | } |
614 | } | |
615 | /* end of while(1) looping forever if we can't force a signal */ | |
616 | ||
617 | /* Did we come from a system call? */ | |
2b163b71 KM |
618 | if (in_syscall) |
619 | insert_restart_trampoline(regs); | |
1da177e4 LT |
620 | |
621 | DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n", | |
622 | regs->gr[28]); | |
623 | ||
4650f0a5 KM |
624 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) { |
625 | clear_thread_flag(TIF_RESTORE_SIGMASK); | |
626 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); | |
627 | } | |
628 | ||
629 | return; | |
630 | } | |
631 | ||
632 | void do_notify_resume(struct pt_regs *regs, long in_syscall) | |
633 | { | |
634 | if (test_thread_flag(TIF_SIGPENDING) || | |
635 | test_thread_flag(TIF_RESTORE_SIGMASK)) | |
636 | do_signal(regs, in_syscall); | |
d0420c83 DH |
637 | |
638 | if (test_thread_flag(TIF_NOTIFY_RESUME)) { | |
639 | clear_thread_flag(TIF_NOTIFY_RESUME); | |
640 | tracehook_notify_resume(regs); | |
ee18d64c DH |
641 | if (current->replacement_session_keyring) |
642 | key_replace_session_keyring(); | |
d0420c83 | 643 | } |
1da177e4 | 644 | } |