korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-24 04:34:08 +08:00
Code Issues Packages Projects Releases Wiki Activity
775ecf8714
linux/arch/m68knommu/kernel/signal.c
Greg Ungerer bb28632c0d [PATCH] m68knommu: check DEBUG defined arch code 
Don't rely on DEBUG having a value, check for it being defined.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-25 17:43:34 -07:00

796 lines
20 KiB
C
Raw Blame History

/*
* linux/arch/m68knommu/kernel/signal.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
/*
* Linux/m68k support by Hamish Macdonald
*
* 68060 fixes by Jesper Skov
*
* 1997-12-01 Modified for POSIX.1b signals by Andreas Schwab
*
* mathemu support by Roman Zippel
* (Note: fpstate in the signal context is completely ignored for the emulator
* and the internal floating point format is put on stack)
*/
/*
* ++roman (07/09/96): implemented signal stacks (specially for tosemu on
* Atari :-) Current limitation: Only one sigstack can be active at one time.
* If a second signal with SA_ONSTACK set arrives while working on a sigstack,
* SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested
* signal handlers!
*/
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/syscalls.h>
#include <linux/errno.h>
#include <linux/wait.h>
#include <linux/ptrace.h>
#include <linux/unistd.h>
#include <linux/stddef.h>
#include <linux/highuid.h>
#include <linux/tty.h>
#include <linux/personality.h>
#include <linux/binfmts.h>
#include <asm/setup.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/traps.h>
#include <asm/ucontext.h>
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs);
/*
* Atomically swap in the new signal mask, and wait for a signal.
*/
asmlinkage int do_sigsuspend(struct pt_regs *regs)
{
old_sigset_t mask = regs->d3;
sigset_t saveset;
mask &= _BLOCKABLE;
spin_lock_irq(&current->sighand->siglock);
saveset = current->blocked;
siginitset(&current->blocked, mask);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
regs->d0 = -EINTR;
while (1) {
current->state = TASK_INTERRUPTIBLE;
schedule();
if (do_signal(&saveset, regs))
return -EINTR;
}
}
asmlinkage int
do_rt_sigsuspend(struct pt_regs *regs)
{
sigset_t *unewset = (sigset_t *)regs->d1;
size_t sigsetsize = (size_t)regs->d2;
sigset_t saveset, newset;
/* XXX: Don't preclude handling different sized sigset_t's. */
if (sigsetsize != sizeof(sigset_t))
return -EINVAL;
if (copy_from_user(&newset, unewset, sizeof(newset)))
return -EFAULT;
sigdelsetmask(&newset, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
saveset = current->blocked;
current->blocked = newset;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
regs->d0 = -EINTR;
while (1) {
current->state = TASK_INTERRUPTIBLE;
schedule();
if (do_signal(&saveset, regs))
return -EINTR;
}
}
asmlinkage int
sys_sigaction(int sig, const struct old_sigaction *act,
struct old_sigaction *oact)
{
struct k_sigaction new_ka, old_ka;
int ret;
if (act) {
old_sigset_t mask;
if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
__get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
__get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
return -EFAULT;
__get_user(new_ka.sa.sa_flags, &act->sa_flags);
__get_user(mask, &act->sa_mask);
siginitset(&new_ka.sa.sa_mask, mask);
}
ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
if (!ret && oact) {
if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
__put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
__put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
return -EFAULT;
__put_user(old_ka.sa.sa_flags, &oact->sa_flags);
__put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
}
return ret;
}
asmlinkage int
sys_sigaltstack(const stack_t *uss, stack_t *uoss)
{
return do_sigaltstack(uss, uoss, rdusp());
}
/*
* Do a signal return; undo the signal stack.
*
* Keep the return code on the stack quadword aligned!
* That makes the cache flush below easier.
*/
struct sigframe
{
char *pretcode;
int sig;
int code;
struct sigcontext *psc;
char retcode[8];
unsigned long extramask[_NSIG_WORDS-1];
struct sigcontext sc;
};
struct rt_sigframe
{
char *pretcode;
int sig;
struct siginfo *pinfo;
void *puc;
char retcode[8];
struct siginfo info;
struct ucontext uc;
};
#ifdef CONFIG_FPU
static unsigned char fpu_version = 0; /* version number of fpu, set by setup_frame */
static inline int restore_fpu_state(struct sigcontext *sc)
{
int err = 1;
if (FPU_IS_EMU) {
/* restore registers */
memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12);
memcpy(current->thread.fp, sc->sc_fpregs, 24);
return 0;
}
if (sc->sc_fpstate[0]) {
/* Verify the frame format. */
if (sc->sc_fpstate[0] != fpu_version)
goto out;
__asm__ volatile (".chip 68k/68881\n\t"
"fmovemx %0,%/fp0-%/fp1\n\t"
"fmoveml %1,%/fpcr/%/fpsr/%/fpiar\n\t"
".chip 68k"
: /* no outputs */
: "m" (*sc->sc_fpregs), "m" (*sc->sc_fpcntl));
}
__asm__ volatile (".chip 68k/68881\n\t"
"frestore %0\n\t"
".chip 68k" : : "m" (*sc->sc_fpstate));
err = 0;
out:
return err;
}
#define FPCONTEXT_SIZE 216
#define uc_fpstate uc_filler[0]
#define uc_formatvec uc_filler[FPCONTEXT_SIZE/4]
#define uc_extra uc_filler[FPCONTEXT_SIZE/4+1]
static inline int rt_restore_fpu_state(struct ucontext *uc)
{
unsigned char fpstate[FPCONTEXT_SIZE];
int context_size = 0;
fpregset_t fpregs;
int err = 1;
if (FPU_IS_EMU) {
/* restore fpu control register */
if (__copy_from_user(current->thread.fpcntl,
&uc->uc_mcontext.fpregs.f_pcr, 12))
goto out;
/* restore all other fpu register */
if (__copy_from_user(current->thread.fp,
uc->uc_mcontext.fpregs.f_fpregs, 96))
goto out;
return 0;
}
if (__get_user(*(long *)fpstate, (long *)&uc->uc_fpstate))
goto out;
if (fpstate[0]) {
context_size = fpstate[1];
/* Verify the frame format. */
if (fpstate[0] != fpu_version)
goto out;
if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs,
sizeof(fpregs)))
goto out;
__asm__ volatile (".chip 68k/68881\n\t"
"fmovemx %0,%/fp0-%/fp7\n\t"
"fmoveml %1,%/fpcr/%/fpsr/%/fpiar\n\t"
".chip 68k"
: /* no outputs */
: "m" (*fpregs.f_fpregs),
"m" (fpregs.f_pcr));
}
if (context_size &&
__copy_from_user(fpstate + 4, (long *)&uc->uc_fpstate + 1,
context_size))
goto out;
__asm__ volatile (".chip 68k/68881\n\t"
"frestore %0\n\t"
".chip 68k" : : "m" (*fpstate));
err = 0;
out:
return err;
}
#endif
static inline int
restore_sigcontext(struct pt_regs *regs, struct sigcontext *usc, void *fp,
int *pd0)
{
int formatvec;
struct sigcontext context;
int err = 0;
/* get previous context */
if (copy_from_user(&context, usc, sizeof(context)))
goto badframe;
/* restore passed registers */
regs->d1 = context.sc_d1;
regs->a0 = context.sc_a0;
regs->a1 = context.sc_a1;
((struct switch_stack *)regs - 1)->a5 = context.sc_a5;
regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff);
regs->pc = context.sc_pc;
regs->orig_d0 = -1; /* disable syscall checks */
wrusp(context.sc_usp);
formatvec = context.sc_formatvec;
regs->format = formatvec >> 12;
regs->vector = formatvec & 0xfff;
#ifdef CONFIG_FPU
err = restore_fpu_state(&context);
#endif
*pd0 = context.sc_d0;
return err;
badframe:
return 1;
}
static inline int
rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw,
struct ucontext *uc, int *pd0)
{
int temp;
greg_t *gregs = uc->uc_mcontext.gregs;
unsigned long usp;
int err;
err = __get_user(temp, &uc->uc_mcontext.version);
if (temp != MCONTEXT_VERSION)
goto badframe;
/* restore passed registers */
err |= __get_user(regs->d0, &gregs[0]);
err |= __get_user(regs->d1, &gregs[1]);
err |= __get_user(regs->d2, &gregs[2]);
err |= __get_user(regs->d3, &gregs[3]);
err |= __get_user(regs->d4, &gregs[4]);
err |= __get_user(regs->d5, &gregs[5]);
err |= __get_user(sw->d6, &gregs[6]);
err |= __get_user(sw->d7, &gregs[7]);
err |= __get_user(regs->a0, &gregs[8]);
err |= __get_user(regs->a1, &gregs[9]);
err |= __get_user(regs->a2, &gregs[10]);
err |= __get_user(sw->a3, &gregs[11]);
err |= __get_user(sw->a4, &gregs[12]);
err |= __get_user(sw->a5, &gregs[13]);
err |= __get_user(sw->a6, &gregs[14]);
err |= __get_user(usp, &gregs[15]);
wrusp(usp);
err |= __get_user(regs->pc, &gregs[16]);
err |= __get_user(temp, &gregs[17]);
regs->sr = (regs->sr & 0xff00) | (temp & 0xff);
regs->orig_d0 = -1; /* disable syscall checks */
regs->format = temp >> 12;
regs->vector = temp & 0xfff;
if (do_sigaltstack(&uc->uc_stack, NULL, usp) == -EFAULT)
goto badframe;
*pd0 = regs->d0;
return err;
badframe:
return 1;
}
asmlinkage int do_sigreturn(unsigned long __unused)
{
struct switch_stack *sw = (struct switch_stack *) &__unused;
struct pt_regs *regs = (struct pt_regs *) (sw + 1);
unsigned long usp = rdusp();
struct sigframe *frame = (struct sigframe *)(usp - 4);
sigset_t set;
int d0;
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__get_user(set.sig[0], &frame->sc.sc_mask) ||
(_NSIG_WORDS > 1 &&
__copy_from_user(&set.sig[1], &frame->extramask,
sizeof(frame->extramask))))
goto badframe;
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (restore_sigcontext(regs, &frame->sc, frame + 1, &d0))
goto badframe;
return d0;
badframe:
force_sig(SIGSEGV, current);
return 0;
}
asmlinkage int do_rt_sigreturn(unsigned long __unused)
{
struct switch_stack *sw = (struct switch_stack *) &__unused;
struct pt_regs *regs = (struct pt_regs *) (sw + 1);
unsigned long usp = rdusp();
struct rt_sigframe *frame = (struct rt_sigframe *)(usp - 4);
sigset_t set;
int d0;
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
goto badframe;
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (rt_restore_ucontext(regs, sw, &frame->uc, &d0))
goto badframe;
return d0;
badframe:
force_sig(SIGSEGV, current);
return 0;
}
#ifdef CONFIG_FPU
/*
* Set up a signal frame.
*/
static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs)
{
if (FPU_IS_EMU) {
/* save registers */
memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12);
memcpy(sc->sc_fpregs, current->thread.fp, 24);
return;
}
__asm__ volatile (".chip 68k/68881\n\t"
"fsave %0\n\t"
".chip 68k"
: : "m" (*sc->sc_fpstate) : "memory");
if (sc->sc_fpstate[0]) {
fpu_version = sc->sc_fpstate[0];
__asm__ volatile (".chip 68k/68881\n\t"
"fmovemx %/fp0-%/fp1,%0\n\t"
"fmoveml %/fpcr/%/fpsr/%/fpiar,%1\n\t"
".chip 68k"
: /* no outputs */
: "m" (*sc->sc_fpregs),
"m" (*sc->sc_fpcntl)
: "memory");
}
}
static inline int rt_save_fpu_state(struct ucontext *uc, struct pt_regs *regs)
{
unsigned char fpstate[FPCONTEXT_SIZE];
int context_size = 0;
int err = 0;
if (FPU_IS_EMU) {
/* save fpu control register */
err |= copy_to_user(&uc->uc_mcontext.fpregs.f_pcr,
current->thread.fpcntl, 12);
/* save all other fpu register */
err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs,
current->thread.fp, 96);
return err;
}
__asm__ volatile (".chip 68k/68881\n\t"
"fsave %0\n\t"
".chip 68k"
: : "m" (*fpstate) : "memory");
err |= __put_user(*(long *)fpstate, (long *)&uc->uc_fpstate);
if (fpstate[0]) {
fpregset_t fpregs;
context_size = fpstate[1];
fpu_version = fpstate[0];
__asm__ volatile (".chip 68k/68881\n\t"
"fmovemx %/fp0-%/fp7,%0\n\t"
"fmoveml %/fpcr/%/fpsr/%/fpiar,%1\n\t"
".chip 68k"
: /* no outputs */
: "m" (*fpregs.f_fpregs),
"m" (fpregs.f_pcr)
: "memory");
err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs,
sizeof(fpregs));
}
if (context_size)
err |= copy_to_user((long *)&uc->uc_fpstate + 1, fpstate + 4,
context_size);
return err;
}
#endif
static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs,
unsigned long mask)
{
sc->sc_mask = mask;
sc->sc_usp = rdusp();
sc->sc_d0 = regs->d0;
sc->sc_d1 = regs->d1;
sc->sc_a0 = regs->a0;
sc->sc_a1 = regs->a1;
sc->sc_a5 = ((struct switch_stack *)regs - 1)->a5;
sc->sc_sr = regs->sr;
sc->sc_pc = regs->pc;
sc->sc_formatvec = regs->format << 12 | regs->vector;
#ifdef CONFIG_FPU
save_fpu_state(sc, regs);
#endif
}
static inline int rt_setup_ucontext(struct ucontext *uc, struct pt_regs *regs)
{
struct switch_stack *sw = (struct switch_stack *)regs - 1;
greg_t *gregs = uc->uc_mcontext.gregs;
int err = 0;
err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version);
err |= __put_user(regs->d0, &gregs[0]);
err |= __put_user(regs->d1, &gregs[1]);
err |= __put_user(regs->d2, &gregs[2]);
err |= __put_user(regs->d3, &gregs[3]);
err |= __put_user(regs->d4, &gregs[4]);
err |= __put_user(regs->d5, &gregs[5]);
err |= __put_user(sw->d6, &gregs[6]);
err |= __put_user(sw->d7, &gregs[7]);
err |= __put_user(regs->a0, &gregs[8]);
err |= __put_user(regs->a1, &gregs[9]);
err |= __put_user(regs->a2, &gregs[10]);
err |= __put_user(sw->a3, &gregs[11]);
err |= __put_user(sw->a4, &gregs[12]);
err |= __put_user(sw->a5, &gregs[13]);
err |= __put_user(sw->a6, &gregs[14]);
err |= __put_user(rdusp(), &gregs[15]);
err |= __put_user(regs->pc, &gregs[16]);
err |= __put_user(regs->sr, &gregs[17]);
#ifdef CONFIG_FPU
err |= rt_save_fpu_state(uc, regs);
#endif
return err;
}
static inline void push_cache (unsigned long vaddr)
{
}
static inline void *
get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
{
unsigned long usp;
/* Default to using normal stack. */
usp = rdusp();
/* This is the X/Open sanctioned signal stack switching. */
if (ka->sa.sa_flags & SA_ONSTACK) {
if (!sas_ss_flags(usp))
usp = current->sas_ss_sp + current->sas_ss_size;
}
return (void *)((usp - frame_size) & -8UL);
}
static void setup_frame (int sig, struct k_sigaction *ka,
sigset_t *set, struct pt_regs *regs)
{
struct sigframe *frame;
struct sigcontext context;
int err = 0;
frame = get_sigframe(ka, regs, sizeof(*frame));
err |= __put_user((current_thread_info()->exec_domain
&& current_thread_info()->exec_domain->signal_invmap
&& sig < 32
? current_thread_info()->exec_domain->signal_invmap[sig]
: sig),
&frame->sig);
err |= __put_user(regs->vector, &frame->code);
err |= __put_user(&frame->sc, &frame->psc);
if (_NSIG_WORDS > 1)
err |= copy_to_user(frame->extramask, &set->sig[1],
sizeof(frame->extramask));
setup_sigcontext(&context, regs, set->sig[0]);
err |= copy_to_user (&frame->sc, &context, sizeof(context));
/* Set up to return from userspace. */
err |= __put_user(frame->retcode, &frame->pretcode);
/* moveq #,d0; trap #0 */
err |= __put_user(0x70004e40 + (__NR_sigreturn << 16),
(long *)(frame->retcode));
if (err)
goto give_sigsegv;
push_cache ((unsigned long) &frame->retcode);
/* Set up registers for signal handler */
wrusp ((unsigned long) frame);
regs->pc = (unsigned long) ka->sa.sa_handler;
((struct switch_stack *)regs - 1)->a5 = current->mm->start_data;
regs->format = 0x4; /*set format byte to make stack appear modulo 4
which it will be when doing the rte */
adjust_stack:
/* Prepare to skip over the extra stuff in the exception frame. */
if (regs->stkadj) {
struct pt_regs *tregs =
(struct pt_regs *)((ulong)regs + regs->stkadj);
#if defined(DEBUG)
printk(KERN_DEBUG "Performing stackadjust=%04x\n", regs->stkadj);
#endif
/* This must be copied with decreasing addresses to
handle overlaps. */
tregs->vector = 0;
tregs->format = 0;
tregs->pc = regs->pc;
tregs->sr = regs->sr;
}
return;
give_sigsegv:
force_sigsegv(sig, current);
goto adjust_stack;
}
static void setup_rt_frame (int sig, struct k_sigaction *ka, siginfo_t *info,
sigset_t *set, struct pt_regs *regs)
{
struct rt_sigframe *frame;
int err = 0;
frame = get_sigframe(ka, regs, sizeof(*frame));
err |= __put_user((current_thread_info()->exec_domain
&& current_thread_info()->exec_domain->signal_invmap
&& sig < 32
? current_thread_info()->exec_domain->signal_invmap[sig]
: sig),
&frame->sig);
err |= __put_user(&frame->info, &frame->pinfo);
err |= __put_user(&frame->uc, &frame->puc);
err |= copy_siginfo_to_user(&frame->info, info);
/* Create the ucontext. */
err |= __put_user(0, &frame->uc.uc_flags);
err |= __put_user(0, &frame->uc.uc_link);
err |= __put_user((void *)current->sas_ss_sp,
&frame->uc.uc_stack.ss_sp);
err |= __put_user(sas_ss_flags(rdusp()),
&frame->uc.uc_stack.ss_flags);
err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
err |= rt_setup_ucontext(&frame->uc, regs);
err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set));
/* Set up to return from userspace. */
err |= __put_user(frame->retcode, &frame->pretcode);
/* moveq #,d0; notb d0; trap #0 */
err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16),
(long *)(frame->retcode + 0));
err |= __put_user(0x4e40, (short *)(frame->retcode + 4));
if (err)
goto give_sigsegv;
push_cache ((unsigned long) &frame->retcode);
/* Set up registers for signal handler */
wrusp ((unsigned long) frame);
regs->pc = (unsigned long) ka->sa.sa_handler;
((struct switch_stack *)regs - 1)->a5 = current->mm->start_data;
regs->format = 0x4; /*set format byte to make stack appear modulo 4
which it will be when doing the rte */
adjust_stack:
/* Prepare to skip over the extra stuff in the exception frame. */
if (regs->stkadj) {
struct pt_regs *tregs =
(struct pt_regs *)((ulong)regs + regs->stkadj);
#if defined(DEBUG)
printk(KERN_DEBUG "Performing stackadjust=%04x\n", regs->stkadj);
#endif
/* This must be copied with decreasing addresses to
handle overlaps. */
tregs->vector = 0;
tregs->format = 0;
tregs->pc = regs->pc;
tregs->sr = regs->sr;
}
return;
give_sigsegv:
force_sigsegv(sig, current);
goto adjust_stack;
}
static inline void
handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler)
{
switch (regs->d0) {
case -ERESTARTNOHAND:
if (!has_handler)
goto do_restart;
regs->d0 = -EINTR;
break;
case -ERESTARTSYS:
if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) {
regs->d0 = -EINTR;
break;
}
/* fallthrough */
case -ERESTARTNOINTR:
do_restart:
regs->d0 = regs->orig_d0;
regs->pc -= 2;
break;
}
}
/*
* OK, we're invoking a handler
*/
static void
handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
sigset_t *oldset, struct pt_regs *regs)
{
/* are we from a system call? */
if (regs->orig_d0 >= 0)
/* If so, check system call restarting.. */
handle_restart(regs, ka, 1);
/* set up the stack frame */
if (ka->sa.sa_flags & SA_SIGINFO)
setup_rt_frame(sig, ka, info, oldset, regs);
else
setup_frame(sig, ka, oldset, regs);
if (ka->sa.sa_flags & SA_ONESHOT)
ka->sa.sa_handler = SIG_DFL;
spin_lock_irq(&current->sighand->siglock);
sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
if (!(ka->sa.sa_flags & SA_NODEFER))
sigaddset(&current->blocked,sig);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
}
/*
* Note that 'init' is a special process: it doesn't get signals it doesn't
* want to handle. Thus you cannot kill init even with a SIGKILL even by
* mistake.
*/
asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs)
{
struct k_sigaction ka;
siginfo_t info;
int signr;
/*
* We want the common case to go fast, which
* is why we may in certain cases get here from
* kernel mode. Just return without doing anything
* if so.
*/
if (!user_mode(regs))
return 1;
if (!oldset)
oldset = &current->blocked;
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
if (signr > 0) {
/* Whee! Actually deliver the signal. */
handle_signal(signr, &ka, &info, oldset, regs);
return 1;
}
/* Did we come from a system call? */
if (regs->orig_d0 >= 0) {
/* Restart the system call - no handlers present */
if (regs->d0 == -ERESTARTNOHAND
|| regs->d0 == -ERESTARTSYS
|| regs->d0 == -ERESTARTNOINTR) {
regs->d0 = regs->orig_d0;
regs->pc -= 2;
} else if (regs->d0 == -ERESTART_RESTARTBLOCK) {
regs->d0 = __NR_restart_syscall;
regs->pc -= 2;
}
}
return 0;
}
Reference in New Issue View Git Blame Copy Permalink