1 /* $NetBSD: compat_13_machdep.c,v 1.22 2023/05/28 08:21:24 andvar Exp $ */
2
3 /*
4 * Copyright 1996 The Board of Trustees of The Leland Stanford
5 * Junior University. All Rights Reserved.
6 *
7 * Permission to use, copy, modify, and distribute this
8 * software and its documentation for any purpose and without
9 * fee is hereby granted, provided that the above copyright
10 * notice appear in all copies. Stanford University
11 * makes no representations about the suitability of this
12 * software for any purpose. It is provided "as is" without
13 * express or implied warranty.
14 */
15
16 #include <sys/cdefs.h> /* RCS ID & Copyright macro defns */
17
18 __KERNEL_RCSID(0, "$NetBSD: compat_13_machdep.c,v 1.22 2023/05/28 08:21:24 andvar Exp $");
19
20 #include <sys/param.h>
21 #include <sys/systm.h>
22 #include <sys/signalvar.h>
23 #include <sys/kernel.h>
24 #include <sys/proc.h>
25 #include <sys/mount.h>
26 #include <sys/syscallargs.h>
27
28 #include <compat/sys/signal.h>
29 #include <compat/sys/signalvar.h>
30
31 #include <mips/regnum.h>
32 #include <mips/locore.h>
33 #include <mips/pcb.h>
34
35 #ifdef DEBUG
36 extern int sigdebug;
37 /* XXX defined in mips_machdep.c */
38 #define SDB_FOLLOW 0x01
39 #define SDB_KSTACK 0x02
40 #define SDB_FPSTATE 0x04
41 #endif
42
43 #if !defined(__mips_o32)
44 #define fpreg fpreg_oabi
45 #endif
46
47 int
compat_13_sys_sigreturn(struct lwp * l,const struct compat_13_sys_sigreturn_args * uap,register_t * retval)48 compat_13_sys_sigreturn(struct lwp *l, const struct compat_13_sys_sigreturn_args *uap, register_t *retval)
49 {
50 /* {
51 syscallarg(struct sigcontext13 *) sigcntxp;
52 } */
53 struct sigcontext13 *scp, ksc;
54 struct proc *p = l->l_proc;
55 int error;
56 struct trapframe *tf = l->l_md.md_utf;
57 sigset_t mask;
58
59 #if !defined(__mips_o32)
60 if (p->p_md.md_abi != _MIPS_BSD_API_O32)
61 return ENOSYS;
62 #endif
63
64 /*
65 * The trampoline code hands us the context.
66 * It is unsafe to keep track of it ourselves, in the event that a
67 * program jumps out of a signal handler.
68 */
69 scp = SCARG(uap, sigcntxp);
70 #ifdef DEBUG
71 if (sigdebug & SDB_FOLLOW)
72 printf("sigreturn13: pid %d, scp %p\n", p->p_pid, scp);
73 #endif
74 if ((error = copyin(scp, &ksc, sizeof(ksc))) != 0)
75 return (error);
76
77 if ((uint32_t)ksc.sc_regs[_R_ZERO] != 0xacedbadeU)/* magic number */
78 return (EINVAL);
79
80 /* Restore the register context. */
81 tf->tf_regs[_R_PC] = ksc.sc_pc;
82 tf->tf_regs[_R_MULLO] = ksc.mullo;
83 tf->tf_regs[_R_MULHI] = ksc.mulhi;
84 #if defined(__mips_o32)
85 memcpy(&tf->tf_regs[1], &scp->sc_regs[1],
86 sizeof(scp->sc_regs) - sizeof(scp->sc_regs[0]));
87 #else
88 for (size_t i = 1; i < __arraycount(scp->sc_regs); i++)
89 tf->tf_regs[i] = scp->sc_regs[i];
90 #endif
91 if (scp->sc_fpused) {
92 struct pcb * const pcb = lwp_getpcb(l);
93 *(struct fpreg *)&pcb->pcb_fpregs = *(struct fpreg *)scp->sc_fpregs;
94 }
95
96 mutex_enter(p->p_lock);
97
98 /* Restore signal stack. */
99 if (ksc.sc_onstack & SS_ONSTACK)
100 l->l_sigstk.ss_flags |= SS_ONSTACK;
101 else
102 l->l_sigstk.ss_flags &= ~SS_ONSTACK;
103
104 mutex_exit(p->p_lock);
105
106 /* Restore signal mask-> */
107 native_sigset13_to_sigset(&ksc.sc_mask, &mask);
108 (void) sigprocmask1(l, SIG_SETMASK, &mask, 0);
109
110 return (EJUSTRETURN);
111 }
112