2 * linux/arch/unicore32/kernel/signal.c
4 * Code specific to PKUnity SoC and UniCore ISA
6 * Copyright (C) 2001-2010 GUAN Xue-tao
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
12 #include <linux/errno.h>
13 #include <linux/signal.h>
14 #include <linux/personality.h>
15 #include <linux/freezer.h>
16 #include <linux/uaccess.h>
17 #include <linux/tracehook.h>
18 #include <linux/elf.h>
19 #include <linux/unistd.h>
21 #include <asm/cacheflush.h>
22 #include <asm/ucontext.h>
25 * For UniCore syscalls, we encode the syscall number into the instruction.
27 #define SWI_SYS_SIGRETURN (0xff000000) /* error number for new abi */
28 #define SWI_SYS_RT_SIGRETURN (0xff000000 | (__NR_rt_sigreturn))
29 #define SWI_SYS_RESTART (0xff000000 | (__NR_restart_syscall))
31 #define KERN_SIGRETURN_CODE (KUSER_VECPAGE_BASE + 0x00000500)
32 #define KERN_RESTART_CODE (KERN_SIGRETURN_CODE + sizeof(sigreturn_codes))
34 const unsigned long sigreturn_codes[3] = {
35 SWI_SYS_SIGRETURN, SWI_SYS_RT_SIGRETURN,
38 const unsigned long syscall_restart_code[2] = {
39 SWI_SYS_RESTART, /* swi __NR_restart_syscall */
40 0x69efc004, /* ldr pc, [sp], #4 */
44 * Do a signal return; undo the signal stack. These are aligned to 64-bit.
48 unsigned long retcode[2];
56 static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf)
61 err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));
63 set_current_blocked(&set);
65 err |= __get_user(regs->UCreg_00, &sf->uc.uc_mcontext.regs.UCreg_00);
66 err |= __get_user(regs->UCreg_01, &sf->uc.uc_mcontext.regs.UCreg_01);
67 err |= __get_user(regs->UCreg_02, &sf->uc.uc_mcontext.regs.UCreg_02);
68 err |= __get_user(regs->UCreg_03, &sf->uc.uc_mcontext.regs.UCreg_03);
69 err |= __get_user(regs->UCreg_04, &sf->uc.uc_mcontext.regs.UCreg_04);
70 err |= __get_user(regs->UCreg_05, &sf->uc.uc_mcontext.regs.UCreg_05);
71 err |= __get_user(regs->UCreg_06, &sf->uc.uc_mcontext.regs.UCreg_06);
72 err |= __get_user(regs->UCreg_07, &sf->uc.uc_mcontext.regs.UCreg_07);
73 err |= __get_user(regs->UCreg_08, &sf->uc.uc_mcontext.regs.UCreg_08);
74 err |= __get_user(regs->UCreg_09, &sf->uc.uc_mcontext.regs.UCreg_09);
75 err |= __get_user(regs->UCreg_10, &sf->uc.uc_mcontext.regs.UCreg_10);
76 err |= __get_user(regs->UCreg_11, &sf->uc.uc_mcontext.regs.UCreg_11);
77 err |= __get_user(regs->UCreg_12, &sf->uc.uc_mcontext.regs.UCreg_12);
78 err |= __get_user(regs->UCreg_13, &sf->uc.uc_mcontext.regs.UCreg_13);
79 err |= __get_user(regs->UCreg_14, &sf->uc.uc_mcontext.regs.UCreg_14);
80 err |= __get_user(regs->UCreg_15, &sf->uc.uc_mcontext.regs.UCreg_15);
81 err |= __get_user(regs->UCreg_16, &sf->uc.uc_mcontext.regs.UCreg_16);
82 err |= __get_user(regs->UCreg_17, &sf->uc.uc_mcontext.regs.UCreg_17);
83 err |= __get_user(regs->UCreg_18, &sf->uc.uc_mcontext.regs.UCreg_18);
84 err |= __get_user(regs->UCreg_19, &sf->uc.uc_mcontext.regs.UCreg_19);
85 err |= __get_user(regs->UCreg_20, &sf->uc.uc_mcontext.regs.UCreg_20);
86 err |= __get_user(regs->UCreg_21, &sf->uc.uc_mcontext.regs.UCreg_21);
87 err |= __get_user(regs->UCreg_22, &sf->uc.uc_mcontext.regs.UCreg_22);
88 err |= __get_user(regs->UCreg_23, &sf->uc.uc_mcontext.regs.UCreg_23);
89 err |= __get_user(regs->UCreg_24, &sf->uc.uc_mcontext.regs.UCreg_24);
90 err |= __get_user(regs->UCreg_25, &sf->uc.uc_mcontext.regs.UCreg_25);
91 err |= __get_user(regs->UCreg_26, &sf->uc.uc_mcontext.regs.UCreg_26);
92 err |= __get_user(regs->UCreg_fp, &sf->uc.uc_mcontext.regs.UCreg_fp);
93 err |= __get_user(regs->UCreg_ip, &sf->uc.uc_mcontext.regs.UCreg_ip);
94 err |= __get_user(regs->UCreg_sp, &sf->uc.uc_mcontext.regs.UCreg_sp);
95 err |= __get_user(regs->UCreg_lr, &sf->uc.uc_mcontext.regs.UCreg_lr);
96 err |= __get_user(regs->UCreg_pc, &sf->uc.uc_mcontext.regs.UCreg_pc);
97 err |= __get_user(regs->UCreg_asr, &sf->uc.uc_mcontext.regs.UCreg_asr);
99 err |= !valid_user_regs(regs);
104 asmlinkage int __sys_rt_sigreturn(struct pt_regs *regs)
106 struct rt_sigframe __user *frame;
108 /* Always make any pending restarted system calls return -EINTR */
109 current_thread_info()->restart_block.fn = do_no_restart_syscall;
112 * Since we stacked the signal on a 64-bit boundary,
113 * then 'sp' should be word aligned here. If it's
114 * not, then the user is trying to mess with us.
116 if (regs->UCreg_sp & 7)
119 frame = (struct rt_sigframe __user *)regs->UCreg_sp;
121 if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
124 if (restore_sigframe(regs, &frame->sig))
127 if (do_sigaltstack(&frame->sig.uc.uc_stack, NULL, regs->UCreg_sp)
131 return regs->UCreg_00;
134 force_sig(SIGSEGV, current);
138 static int setup_sigframe(struct sigframe __user *sf, struct pt_regs *regs,
143 err |= __put_user(regs->UCreg_00, &sf->uc.uc_mcontext.regs.UCreg_00);
144 err |= __put_user(regs->UCreg_01, &sf->uc.uc_mcontext.regs.UCreg_01);
145 err |= __put_user(regs->UCreg_02, &sf->uc.uc_mcontext.regs.UCreg_02);
146 err |= __put_user(regs->UCreg_03, &sf->uc.uc_mcontext.regs.UCreg_03);
147 err |= __put_user(regs->UCreg_04, &sf->uc.uc_mcontext.regs.UCreg_04);
148 err |= __put_user(regs->UCreg_05, &sf->uc.uc_mcontext.regs.UCreg_05);
149 err |= __put_user(regs->UCreg_06, &sf->uc.uc_mcontext.regs.UCreg_06);
150 err |= __put_user(regs->UCreg_07, &sf->uc.uc_mcontext.regs.UCreg_07);
151 err |= __put_user(regs->UCreg_08, &sf->uc.uc_mcontext.regs.UCreg_08);
152 err |= __put_user(regs->UCreg_09, &sf->uc.uc_mcontext.regs.UCreg_09);
153 err |= __put_user(regs->UCreg_10, &sf->uc.uc_mcontext.regs.UCreg_10);
154 err |= __put_user(regs->UCreg_11, &sf->uc.uc_mcontext.regs.UCreg_11);
155 err |= __put_user(regs->UCreg_12, &sf->uc.uc_mcontext.regs.UCreg_12);
156 err |= __put_user(regs->UCreg_13, &sf->uc.uc_mcontext.regs.UCreg_13);
157 err |= __put_user(regs->UCreg_14, &sf->uc.uc_mcontext.regs.UCreg_14);
158 err |= __put_user(regs->UCreg_15, &sf->uc.uc_mcontext.regs.UCreg_15);
159 err |= __put_user(regs->UCreg_16, &sf->uc.uc_mcontext.regs.UCreg_16);
160 err |= __put_user(regs->UCreg_17, &sf->uc.uc_mcontext.regs.UCreg_17);
161 err |= __put_user(regs->UCreg_18, &sf->uc.uc_mcontext.regs.UCreg_18);
162 err |= __put_user(regs->UCreg_19, &sf->uc.uc_mcontext.regs.UCreg_19);
163 err |= __put_user(regs->UCreg_20, &sf->uc.uc_mcontext.regs.UCreg_20);
164 err |= __put_user(regs->UCreg_21, &sf->uc.uc_mcontext.regs.UCreg_21);
165 err |= __put_user(regs->UCreg_22, &sf->uc.uc_mcontext.regs.UCreg_22);
166 err |= __put_user(regs->UCreg_23, &sf->uc.uc_mcontext.regs.UCreg_23);
167 err |= __put_user(regs->UCreg_24, &sf->uc.uc_mcontext.regs.UCreg_24);
168 err |= __put_user(regs->UCreg_25, &sf->uc.uc_mcontext.regs.UCreg_25);
169 err |= __put_user(regs->UCreg_26, &sf->uc.uc_mcontext.regs.UCreg_26);
170 err |= __put_user(regs->UCreg_fp, &sf->uc.uc_mcontext.regs.UCreg_fp);
171 err |= __put_user(regs->UCreg_ip, &sf->uc.uc_mcontext.regs.UCreg_ip);
172 err |= __put_user(regs->UCreg_sp, &sf->uc.uc_mcontext.regs.UCreg_sp);
173 err |= __put_user(regs->UCreg_lr, &sf->uc.uc_mcontext.regs.UCreg_lr);
174 err |= __put_user(regs->UCreg_pc, &sf->uc.uc_mcontext.regs.UCreg_pc);
175 err |= __put_user(regs->UCreg_asr, &sf->uc.uc_mcontext.regs.UCreg_asr);
177 err |= __put_user(current->thread.trap_no,
178 &sf->uc.uc_mcontext.trap_no);
179 err |= __put_user(current->thread.error_code,
180 &sf->uc.uc_mcontext.error_code);
181 err |= __put_user(current->thread.address,
182 &sf->uc.uc_mcontext.fault_address);
183 err |= __put_user(set->sig[0], &sf->uc.uc_mcontext.oldmask);
185 err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(*set));
190 static inline void __user *get_sigframe(struct k_sigaction *ka,
191 struct pt_regs *regs, int framesize)
193 unsigned long sp = regs->UCreg_sp;
197 * This is the X/Open sanctioned signal stack switching.
199 if ((ka->sa.sa_flags & SA_ONSTACK) && !sas_ss_flags(sp))
200 sp = current->sas_ss_sp + current->sas_ss_size;
203 * ATPCS B01 mandates 8-byte alignment
205 frame = (void __user *)((sp - framesize) & ~7);
208 * Check that we can actually write to the signal frame.
210 if (!access_ok(VERIFY_WRITE, frame, framesize))
216 static int setup_return(struct pt_regs *regs, struct k_sigaction *ka,
217 unsigned long __user *rc, void __user *frame, int usig)
219 unsigned long handler = (unsigned long)ka->sa.sa_handler;
220 unsigned long retcode;
221 unsigned long asr = regs->UCreg_asr & ~PSR_f;
223 unsigned int idx = 0;
225 if (ka->sa.sa_flags & SA_SIGINFO)
228 if (__put_user(sigreturn_codes[idx], rc) ||
229 __put_user(sigreturn_codes[idx+1], rc+1))
232 retcode = KERN_SIGRETURN_CODE + (idx << 2);
234 regs->UCreg_00 = usig;
235 regs->UCreg_sp = (unsigned long)frame;
236 regs->UCreg_lr = retcode;
237 regs->UCreg_pc = handler;
238 regs->UCreg_asr = asr;
243 static int setup_frame(int usig, struct k_sigaction *ka,
244 sigset_t *set, struct pt_regs *regs)
246 struct sigframe __user *frame = get_sigframe(ka, regs, sizeof(*frame));
253 * Set uc.uc_flags to a value which sc.trap_no would never have.
255 err |= __put_user(0x5ac3c35a, &frame->uc.uc_flags);
257 err |= setup_sigframe(frame, regs, set);
259 err |= setup_return(regs, ka, frame->retcode, frame, usig);
264 static int setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info,
265 sigset_t *set, struct pt_regs *regs)
267 struct rt_sigframe __user *frame =
268 get_sigframe(ka, regs, sizeof(*frame));
275 err |= copy_siginfo_to_user(&frame->info, info);
277 err |= __put_user(0, &frame->sig.uc.uc_flags);
278 err |= __put_user(NULL, &frame->sig.uc.uc_link);
280 memset(&stack, 0, sizeof(stack));
281 stack.ss_sp = (void __user *)current->sas_ss_sp;
282 stack.ss_flags = sas_ss_flags(regs->UCreg_sp);
283 stack.ss_size = current->sas_ss_size;
284 err |= __copy_to_user(&frame->sig.uc.uc_stack, &stack, sizeof(stack));
286 err |= setup_sigframe(&frame->sig, regs, set);
288 err |= setup_return(regs, ka, frame->sig.retcode, frame, usig);
292 * For realtime signals we must also set the second and third
293 * arguments for the signal handler.
295 regs->UCreg_01 = (unsigned long)&frame->info;
296 regs->UCreg_02 = (unsigned long)&frame->sig.uc;
302 static inline void setup_syscall_restart(struct pt_regs *regs)
304 regs->UCreg_00 = regs->UCreg_ORIG_00;
309 * OK, we're invoking a handler
311 static void handle_signal(unsigned long sig, struct k_sigaction *ka,
312 siginfo_t *info, struct pt_regs *regs, int syscall)
314 struct thread_info *thread = current_thread_info();
315 struct task_struct *tsk = current;
316 sigset_t *oldset = sigmask_to_save();
321 * If we were from a system call, check for system call restarting...
324 switch (regs->UCreg_00) {
325 case -ERESTART_RESTARTBLOCK:
326 case -ERESTARTNOHAND:
327 regs->UCreg_00 = -EINTR;
330 if (!(ka->sa.sa_flags & SA_RESTART)) {
331 regs->UCreg_00 = -EINTR;
335 case -ERESTARTNOINTR:
336 setup_syscall_restart(regs);
341 * translate the signal
343 if (usig < 32 && thread->exec_domain
344 && thread->exec_domain->signal_invmap)
345 usig = thread->exec_domain->signal_invmap[usig];
348 * Set up the stack frame
350 if (ka->sa.sa_flags & SA_SIGINFO)
351 ret = setup_rt_frame(usig, ka, info, oldset, regs);
353 ret = setup_frame(usig, ka, oldset, regs);
356 * Check that the resulting registers are actually sane.
358 ret |= !valid_user_regs(regs);
361 force_sigsegv(sig, tsk);
365 signal_delivered(sig, info, ka, regs, 0);
369 * Note that 'init' is a special process: it doesn't get signals it doesn't
370 * want to handle. Thus you cannot kill init even with a SIGKILL even by
373 * Note that we go through the signals twice: once to check the signals that
374 * the kernel can handle, and then we build all the user-level signal handling
375 * stack-frames in one go after that.
377 static void do_signal(struct pt_regs *regs, int syscall)
379 struct k_sigaction ka;
384 * We want the common case to go fast, which
385 * is why we may in certain cases get here from
386 * kernel mode. Just return without doing anything
389 if (!user_mode(regs))
392 signr = get_signal_to_deliver(&info, &ka, regs, NULL);
394 handle_signal(signr, &ka, &info, regs, syscall);
399 * No signal to deliver to the process - restart the syscall.
402 if (regs->UCreg_00 == -ERESTART_RESTARTBLOCK) {
406 usp = (u32 __user *)regs->UCreg_sp;
408 if (put_user(regs->UCreg_pc, usp) == 0) {
409 regs->UCreg_pc = KERN_RESTART_CODE;
412 force_sigsegv(0, current);
415 if (regs->UCreg_00 == -ERESTARTNOHAND ||
416 regs->UCreg_00 == -ERESTARTSYS ||
417 regs->UCreg_00 == -ERESTARTNOINTR) {
418 setup_syscall_restart(regs);
421 /* If there's no signal to deliver, we just put the saved
424 restore_saved_sigmask();
427 asmlinkage void do_notify_resume(struct pt_regs *regs,
428 unsigned int thread_flags, int syscall)
430 if (thread_flags & _TIF_SIGPENDING)
431 do_signal(regs, syscall);
433 if (thread_flags & _TIF_NOTIFY_RESUME) {
434 clear_thread_flag(TIF_NOTIFY_RESUME);
435 tracehook_notify_resume(regs);
440 * Copy signal return handlers into the vector page, and
441 * set sigreturn to be a pointer to these.
443 void __init early_signal_init(void)
445 memcpy((void *)kuser_vecpage_to_vectors(KERN_SIGRETURN_CODE),
446 sigreturn_codes, sizeof(sigreturn_codes));
447 memcpy((void *)kuser_vecpage_to_vectors(KERN_RESTART_CODE),
448 syscall_restart_code, sizeof(syscall_restart_code));
449 /* Need not to flush icache, since early_trap_init will do it last. */