1 // SPDX-License-Identifier: GPL-2.0-only
3  * Signal Handling for ARC
5  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
7  * vineetg: Jan 2010 (Restarting of timer related syscalls)
10  *  -do_signal() supports TIF_RESTORE_SIGMASK
11  *  -do_signal() no longer needs oldset, required by OLD sys_sigsuspend
12  *  -sys_rt_sigsuspend() now comes from generic code, so discard arch
14  *  -sys_sigsuspend() no longer needs to fudge ptregs, hence that arg removed
15  *  -sys_sigsuspend() no longer loops for do_signal(), sets TIF_xxx and leaves
19  *  -Modified Code to support the uClibc provided userland sigreturn stub
24  *  -In stash_usr_regs( ) and restore_usr_regs( ), save/restore of user regs
29  *  - Support for Realtime Signals
32  *  -ViXS were still seeing crashes when using insmod to load drivers.
38  *  -Exception happens in Delay slot of a JMP, and before user space resumes,
43  *  -FIX: clear the DE bit from status32 in setup_frame( )
72 	v2abi.r30 = regs->r30;  in save_arcv2_regs()
74 	v2abi.r58 = regs->r58;  in save_arcv2_regs()
75 	v2abi.r59 = regs->r59;  in save_arcv2_regs()
79 	err = __copy_to_user(&mctx->v2abi, (void const *)&v2abi, sizeof(v2abi));  in save_arcv2_regs()
90 	err = __copy_from_user(&v2abi, &mctx->v2abi, sizeof(v2abi));  in restore_arcv2_regs()
92 	regs->r30 = v2abi.r30;  in restore_arcv2_regs()
94 	regs->r58 = v2abi.r58;  in restore_arcv2_regs()
95 	regs->r59 = v2abi.r59;  in restore_arcv2_regs()
108 	uregs.scratch.bta	= regs->bta;  in stash_usr_regs()
109 	uregs.scratch.lp_start	= regs->lp_start;  in stash_usr_regs()
110 	uregs.scratch.lp_end	= regs->lp_end;  in stash_usr_regs()
111 	uregs.scratch.lp_count	= regs->lp_count;  in stash_usr_regs()
112 	uregs.scratch.status32	= regs->status32;  in stash_usr_regs()
113 	uregs.scratch.ret	= regs->ret;  in stash_usr_regs()
114 	uregs.scratch.blink	= regs->blink;  in stash_usr_regs()
115 	uregs.scratch.fp	= regs->fp;  in stash_usr_regs()
116 	uregs.scratch.gp	= regs->r26;  in stash_usr_regs()
117 	uregs.scratch.r12	= regs->r12;  in stash_usr_regs()
118 	uregs.scratch.r11	= regs->r11;  in stash_usr_regs()
119 	uregs.scratch.r10	= regs->r10;  in stash_usr_regs()
120 	uregs.scratch.r9	= regs->r9;  in stash_usr_regs()
121 	uregs.scratch.r8	= regs->r8;  in stash_usr_regs()
122 	uregs.scratch.r7	= regs->r7;  in stash_usr_regs()
123 	uregs.scratch.r6	= regs->r6;  in stash_usr_regs()
124 	uregs.scratch.r5	= regs->r5;  in stash_usr_regs()
125 	uregs.scratch.r4	= regs->r4;  in stash_usr_regs()
126 	uregs.scratch.r3	= regs->r3;  in stash_usr_regs()
127 	uregs.scratch.r2	= regs->r2;  in stash_usr_regs()
128 	uregs.scratch.r1	= regs->r1;  in stash_usr_regs()
129 	uregs.scratch.r0	= regs->r0;  in stash_usr_regs()
130 	uregs.scratch.sp	= regs->sp;  in stash_usr_regs()
132 	err = __copy_to_user(&(sf->uc.uc_mcontext.regs.scratch), &uregs.scratch,  in stash_usr_regs()
133 			     sizeof(sf->uc.uc_mcontext.regs.scratch));  in stash_usr_regs()
136 		err |= save_arcv2_regs(&(sf->uc.uc_mcontext), regs);  in stash_usr_regs()
138 	err |= __copy_to_user(&sf->uc.uc_sigmask, set, sizeof(sigset_t));  in stash_usr_regs()
140 	return err ? -EFAULT : 0;  in stash_usr_regs()
149 	err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set));  in restore_usr_regs()
151 				&(sf->uc.uc_mcontext.regs.scratch),  in restore_usr_regs()
152 				sizeof(sf->uc.uc_mcontext.regs.scratch));  in restore_usr_regs()
155 		err |= restore_arcv2_regs(&(sf->uc.uc_mcontext), regs);  in restore_usr_regs()
158 		return -EFAULT;  in restore_usr_regs()
161 	regs->bta	= uregs.scratch.bta;  in restore_usr_regs()
162 	regs->lp_start	= uregs.scratch.lp_start;  in restore_usr_regs()
163 	regs->lp_end	= uregs.scratch.lp_end;  in restore_usr_regs()
164 	regs->lp_count	= uregs.scratch.lp_count;  in restore_usr_regs()
165 	regs->status32	= uregs.scratch.status32;  in restore_usr_regs()
166 	regs->ret	= uregs.scratch.ret;  in restore_usr_regs()
167 	regs->blink	= uregs.scratch.blink;  in restore_usr_regs()
168 	regs->fp	= uregs.scratch.fp;  in restore_usr_regs()
169 	regs->r26	= uregs.scratch.gp;  in restore_usr_regs()
170 	regs->r12	= uregs.scratch.r12;  in restore_usr_regs()
171 	regs->r11	= uregs.scratch.r11;  in restore_usr_regs()
172 	regs->r10	= uregs.scratch.r10;  in restore_usr_regs()
173 	regs->r9	= uregs.scratch.r9;  in restore_usr_regs()
174 	regs->r8	= uregs.scratch.r8;  in restore_usr_regs()
175 	regs->r7	= uregs.scratch.r7;  in restore_usr_regs()
176 	regs->r6	= uregs.scratch.r6;  in restore_usr_regs()
177 	regs->r5	= uregs.scratch.r5;  in restore_usr_regs()
178 	regs->r4	= uregs.scratch.r4;  in restore_usr_regs()
179 	regs->r3	= uregs.scratch.r3;  in restore_usr_regs()
180 	regs->r2	= uregs.scratch.r2;  in restore_usr_regs()
181 	regs->r1	= uregs.scratch.r1;  in restore_usr_regs()
182 	regs->r0	= uregs.scratch.r0;  in restore_usr_regs()
183 	regs->sp	= uregs.scratch.sp;  in restore_usr_regs()
202 	/* Always make any pending restarted system calls return -EINTR */  in SYSCALL_DEFINE0()
203 	current->restart_block.fn = do_no_restart_syscall;  in SYSCALL_DEFINE0()
209 	if (regs->sp & 3)  in SYSCALL_DEFINE0()
212 	sf = (struct rt_sigframe __force __user *)(regs->sp);  in SYSCALL_DEFINE0()
217 	if (__get_user(magic, &sf->sigret_magic))  in SYSCALL_DEFINE0()
221 		if (restore_altstack(&sf->uc.uc_stack))  in SYSCALL_DEFINE0()
237 	regs->status32 |= STATUS_U_MASK;  in SYSCALL_DEFINE0()
239 	return regs->r0;  in SYSCALL_DEFINE0()
253 	unsigned long sp = sigsp(regs->sp, ksig);  in get_sigframe()
260 	/* ATPCS B01 mandates 8-byte alignment */  in get_sigframe()
261 	frame = (void __user *)((sp - framesize) & ~7);  in get_sigframe()
292 	 *  #1: sig-no (common to any handler)  in setup_rt_frame()
296 	if (unlikely(ksig->ka.sa.sa_flags & SA_SIGINFO)) {  in setup_rt_frame()
297 		err |= copy_siginfo_to_user(&sf->info, &ksig->info);  in setup_rt_frame()
298 		err |= __put_user(0, &sf->uc.uc_flags);  in setup_rt_frame()
299 		err |= __put_user(NULL, &sf->uc.uc_link);  in setup_rt_frame()
300 		err |= __save_altstack(&sf->uc.uc_stack, regs->sp);  in setup_rt_frame()
303 		regs->r1 = (unsigned long)&sf->info;  in setup_rt_frame()
304 		regs->r2 = (unsigned long)&sf->uc;  in setup_rt_frame()
313 	err |= __put_user(magic, &sf->sigret_magic);  in setup_rt_frame()
318 	regs->r0 = ksig->sig;  in setup_rt_frame()
321 	regs->ret = (unsigned long)ksig->ka.sa.sa_handler;  in setup_rt_frame()
327 	if(!(ksig->ka.sa.sa_flags & SA_RESTORER))  in setup_rt_frame()
330 	regs->blink = (unsigned long)ksig->ka.sa.sa_restorer;  in setup_rt_frame()
333 	regs->sp = (unsigned long)sf;  in setup_rt_frame()
339 	regs->status32 &= ~STATUS_DE_MASK;  in setup_rt_frame()
340 	regs->status32 |= STATUS_L_MASK;  in setup_rt_frame()
347 	switch (regs->r0) {  in arc_restart_syscall()
348 	case -ERESTART_RESTARTBLOCK:  in arc_restart_syscall()
349 	case -ERESTARTNOHAND:  in arc_restart_syscall()
356 		regs->r0 = -EINTR;   /* ERESTART_xxx is internal */  in arc_restart_syscall()
359 	case -ERESTARTSYS:  in arc_restart_syscall()
365 		if (!(ka->sa.sa_flags & SA_RESTART)) {  in arc_restart_syscall()
366 			regs->r0 = -EINTR;  in arc_restart_syscall()
371 	case -ERESTARTNOINTR:  in arc_restart_syscall()
378 		 * in orig_r0. Rest of relevant reg-file:  in arc_restart_syscall()
379 		 * r8 (syscall num) and (r1 - r7) will be reset to  in arc_restart_syscall()
382 		regs->r0 = regs->orig_r0;  in arc_restart_syscall()
383 		regs->ret -= is_isa_arcv2() ? 2 : 4;  in arc_restart_syscall()
421 		if (regs->r0 == -ERESTARTNOHAND ||  in do_signal()
422 		    regs->r0 == -ERESTARTSYS || regs->r0 == -ERESTARTNOINTR) {  in do_signal()
423 			regs->r0 = regs->orig_r0;  in do_signal()
424 			regs->ret -= is_isa_arcv2() ? 2 : 4;  in do_signal()
425 		} else if (regs->r0 == -ERESTART_RESTARTBLOCK) {  in do_signal()
426 			regs->r8 = __NR_restart_syscall;  in do_signal()
427 			regs->ret -= is_isa_arcv2() ? 2 : 4;  in do_signal()