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linux/arch/sparc64/kernel/signal.c
Steven Rostedt 69be8f1896 [PATCH] convert signal handling of NODEFER to act like other Unix boxes.
It has been reported that the way Linux handles NODEFER for signals is
not consistent with the way other Unix boxes handle it.  I've written a
program to test the behavior of how this flag affects signals and had
several reports from people who ran this on various Unix boxes,
confirming that Linux seems to be unique on the way this is handled.

The way NODEFER affects signals on other Unix boxes is as follows:

1) If NODEFER is set, other signals in sa_mask are still blocked.

2) If NODEFER is set and the signal is in sa_mask, then the signal is
still blocked. (Note: this is the behavior of all tested but Linux _and_
NetBSD 2.0 *).

The way NODEFER affects signals on Linux:

1) If NODEFER is set, other signals are _not_ blocked regardless of
sa_mask (Even NetBSD doesn't do this).

2) If NODEFER is set and the signal is in sa_mask, then the signal being
handled is not blocked.

The patch converts signal handling in all current Linux architectures to
the way most Unix boxes work.

Unix boxes that were tested:  DU4, AIX 5.2, Irix 6.5, NetBSD 2.0, SFU
3.5 on WinXP, AIX 5.3, Mac OSX, and of course Linux 2.6.13-rcX.

* NetBSD was the only other Unix to behave like Linux on point #2. The
main concern was brought up by point #1 which even NetBSD isn't like
Linux.  So with this patch, we leave NetBSD as the lonely one that
behaves differently here with #2.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-08-29 10:03:11 -07:00

688 lines
20 KiB
C

/* $Id: signal.c,v 1.60 2002/02/09 19:49:31 davem Exp $
* arch/sparc64/kernel/signal.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
* Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
* Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
* Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*/
#include <linux/config.h>
#ifdef CONFIG_SPARC32_COMPAT
#include <linux/compat.h> /* for compat_old_sigset_t */
#endif
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/errno.h>
#include <linux/wait.h>
#include <linux/ptrace.h>
#include <linux/unistd.h>
#include <linux/mm.h>
#include <linux/tty.h>
#include <linux/smp_lock.h>
#include <linux/binfmts.h>
#include <linux/bitops.h>
#include <asm/uaccess.h>
#include <asm/ptrace.h>
#include <asm/svr4.h>
#include <asm/pgtable.h>
#include <asm/fpumacro.h>
#include <asm/uctx.h>
#include <asm/siginfo.h>
#include <asm/visasm.h>
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
static int do_signal(sigset_t *oldset, struct pt_regs * regs,
unsigned long orig_o0, int ret_from_syscall);
/* {set, get}context() needed for 64-bit SparcLinux userland. */
asmlinkage void sparc64_set_context(struct pt_regs *regs)
{
struct ucontext __user *ucp = (struct ucontext __user *)
regs->u_regs[UREG_I0];
mc_gregset_t __user *grp;
unsigned long pc, npc, tstate;
unsigned long fp, i7;
unsigned char fenab;
int err;
flush_user_windows();
if (get_thread_wsaved() ||
(((unsigned long)ucp) & (sizeof(unsigned long)-1)) ||
(!__access_ok(ucp, sizeof(*ucp))))
goto do_sigsegv;
grp = &ucp->uc_mcontext.mc_gregs;
err = __get_user(pc, &((*grp)[MC_PC]));
err |= __get_user(npc, &((*grp)[MC_NPC]));
if (err || ((pc | npc) & 3))
goto do_sigsegv;
if (regs->u_regs[UREG_I1]) {
sigset_t set;
if (_NSIG_WORDS == 1) {
if (__get_user(set.sig[0], &ucp->uc_sigmask.sig[0]))
goto do_sigsegv;
} else {
if (__copy_from_user(&set, &ucp->uc_sigmask, sizeof(sigset_t)))
goto do_sigsegv;
}
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
}
if (test_thread_flag(TIF_32BIT)) {
pc &= 0xffffffff;
npc &= 0xffffffff;
}
regs->tpc = pc;
regs->tnpc = npc;
err |= __get_user(regs->y, &((*grp)[MC_Y]));
err |= __get_user(tstate, &((*grp)[MC_TSTATE]));
regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
err |= __get_user(regs->u_regs[UREG_G1], (&(*grp)[MC_G1]));
err |= __get_user(regs->u_regs[UREG_G2], (&(*grp)[MC_G2]));
err |= __get_user(regs->u_regs[UREG_G3], (&(*grp)[MC_G3]));
err |= __get_user(regs->u_regs[UREG_G4], (&(*grp)[MC_G4]));
err |= __get_user(regs->u_regs[UREG_G5], (&(*grp)[MC_G5]));
err |= __get_user(regs->u_regs[UREG_G6], (&(*grp)[MC_G6]));
err |= __get_user(regs->u_regs[UREG_G7], (&(*grp)[MC_G7]));
err |= __get_user(regs->u_regs[UREG_I0], (&(*grp)[MC_O0]));
err |= __get_user(regs->u_regs[UREG_I1], (&(*grp)[MC_O1]));
err |= __get_user(regs->u_regs[UREG_I2], (&(*grp)[MC_O2]));
err |= __get_user(regs->u_regs[UREG_I3], (&(*grp)[MC_O3]));
err |= __get_user(regs->u_regs[UREG_I4], (&(*grp)[MC_O4]));
err |= __get_user(regs->u_regs[UREG_I5], (&(*grp)[MC_O5]));
err |= __get_user(regs->u_regs[UREG_I6], (&(*grp)[MC_O6]));
err |= __get_user(regs->u_regs[UREG_I7], (&(*grp)[MC_O7]));
err |= __get_user(fp, &(ucp->uc_mcontext.mc_fp));
err |= __get_user(i7, &(ucp->uc_mcontext.mc_i7));
err |= __put_user(fp,
(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
err |= __put_user(i7,
(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
err |= __get_user(fenab, &(ucp->uc_mcontext.mc_fpregs.mcfpu_enab));
if (fenab) {
unsigned long *fpregs = current_thread_info()->fpregs;
unsigned long fprs;
fprs_write(0);
err |= __get_user(fprs, &(ucp->uc_mcontext.mc_fpregs.mcfpu_fprs));
if (fprs & FPRS_DL)
err |= copy_from_user(fpregs,
&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs),
(sizeof(unsigned int) * 32));
if (fprs & FPRS_DU)
err |= copy_from_user(fpregs+16,
((unsigned long __user *)&(ucp->uc_mcontext.mc_fpregs.mcfpu_fregs))+16,
(sizeof(unsigned int) * 32));
err |= __get_user(current_thread_info()->xfsr[0],
&(ucp->uc_mcontext.mc_fpregs.mcfpu_fsr));
err |= __get_user(current_thread_info()->gsr[0],
&(ucp->uc_mcontext.mc_fpregs.mcfpu_gsr));
regs->tstate &= ~TSTATE_PEF;
}
if (err)
goto do_sigsegv;
return;
do_sigsegv:
force_sig(SIGSEGV, current);
}
asmlinkage void sparc64_get_context(struct pt_regs *regs)
{
struct ucontext __user *ucp = (struct ucontext __user *)
regs->u_regs[UREG_I0];
mc_gregset_t __user *grp;
mcontext_t __user *mcp;
unsigned long fp, i7;
unsigned char fenab;
int err;
synchronize_user_stack();
if (get_thread_wsaved() || clear_user(ucp, sizeof(*ucp)))
goto do_sigsegv;
#if 1
fenab = 0; /* IMO get_context is like any other system call, thus modifies FPU state -jj */
#else
fenab = (current_thread_info()->fpsaved[0] & FPRS_FEF);
#endif
mcp = &ucp->uc_mcontext;
grp = &mcp->mc_gregs;
/* Skip over the trap instruction, first. */
if (test_thread_flag(TIF_32BIT)) {
regs->tpc = (regs->tnpc & 0xffffffff);
regs->tnpc = (regs->tnpc + 4) & 0xffffffff;
} else {
regs->tpc = regs->tnpc;
regs->tnpc += 4;
}
err = 0;
if (_NSIG_WORDS == 1)
err |= __put_user(current->blocked.sig[0],
(unsigned long __user *)&ucp->uc_sigmask);
else
err |= __copy_to_user(&ucp->uc_sigmask, &current->blocked,
sizeof(sigset_t));
err |= __put_user(regs->tstate, &((*grp)[MC_TSTATE]));
err |= __put_user(regs->tpc, &((*grp)[MC_PC]));
err |= __put_user(regs->tnpc, &((*grp)[MC_NPC]));
err |= __put_user(regs->y, &((*grp)[MC_Y]));
err |= __put_user(regs->u_regs[UREG_G1], &((*grp)[MC_G1]));
err |= __put_user(regs->u_regs[UREG_G2], &((*grp)[MC_G2]));
err |= __put_user(regs->u_regs[UREG_G3], &((*grp)[MC_G3]));
err |= __put_user(regs->u_regs[UREG_G4], &((*grp)[MC_G4]));
err |= __put_user(regs->u_regs[UREG_G5], &((*grp)[MC_G5]));
err |= __put_user(regs->u_regs[UREG_G6], &((*grp)[MC_G6]));
err |= __put_user(regs->u_regs[UREG_G7], &((*grp)[MC_G7]));
err |= __put_user(regs->u_regs[UREG_I0], &((*grp)[MC_O0]));
err |= __put_user(regs->u_regs[UREG_I1], &((*grp)[MC_O1]));
err |= __put_user(regs->u_regs[UREG_I2], &((*grp)[MC_O2]));
err |= __put_user(regs->u_regs[UREG_I3], &((*grp)[MC_O3]));
err |= __put_user(regs->u_regs[UREG_I4], &((*grp)[MC_O4]));
err |= __put_user(regs->u_regs[UREG_I5], &((*grp)[MC_O5]));
err |= __put_user(regs->u_regs[UREG_I6], &((*grp)[MC_O6]));
err |= __put_user(regs->u_regs[UREG_I7], &((*grp)[MC_O7]));
err |= __get_user(fp,
(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[6])));
err |= __get_user(i7,
(&(((struct reg_window __user *)(STACK_BIAS+regs->u_regs[UREG_I6]))->ins[7])));
err |= __put_user(fp, &(mcp->mc_fp));
err |= __put_user(i7, &(mcp->mc_i7));
err |= __put_user(fenab, &(mcp->mc_fpregs.mcfpu_enab));
if (fenab) {
unsigned long *fpregs = current_thread_info()->fpregs;
unsigned long fprs;
fprs = current_thread_info()->fpsaved[0];
if (fprs & FPRS_DL)
err |= copy_to_user(&(mcp->mc_fpregs.mcfpu_fregs), fpregs,
(sizeof(unsigned int) * 32));
if (fprs & FPRS_DU)
err |= copy_to_user(
((unsigned long __user *)&(mcp->mc_fpregs.mcfpu_fregs))+16, fpregs+16,
(sizeof(unsigned int) * 32));
err |= __put_user(current_thread_info()->xfsr[0], &(mcp->mc_fpregs.mcfpu_fsr));
err |= __put_user(current_thread_info()->gsr[0], &(mcp->mc_fpregs.mcfpu_gsr));
err |= __put_user(fprs, &(mcp->mc_fpregs.mcfpu_fprs));
}
if (err)
goto do_sigsegv;
return;
do_sigsegv:
force_sig(SIGSEGV, current);
}
struct rt_signal_frame {
struct sparc_stackf ss;
siginfo_t info;
struct pt_regs regs;
__siginfo_fpu_t __user *fpu_save;
stack_t stack;
sigset_t mask;
__siginfo_fpu_t fpu_state;
};
/* Align macros */
#define RT_ALIGNEDSZ (((sizeof(struct rt_signal_frame) + 7) & (~7)))
/*
* atomically swap in the new signal mask, and wait for a signal.
* This is really tricky on the Sparc, watch out...
*/
asmlinkage void _sigpause_common(old_sigset_t set, struct pt_regs *regs)
{
sigset_t saveset;
#ifdef CONFIG_SPARC32_COMPAT
if (test_thread_flag(TIF_32BIT)) {
extern asmlinkage void _sigpause32_common(compat_old_sigset_t,
struct pt_regs *);
_sigpause32_common(set, regs);
return;
}
#endif
set &= _BLOCKABLE;
spin_lock_irq(&current->sighand->siglock);
saveset = current->blocked;
siginitset(&current->blocked, set);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (test_thread_flag(TIF_32BIT)) {
regs->tpc = (regs->tnpc & 0xffffffff);
regs->tnpc = (regs->tnpc + 4) & 0xffffffff;
} else {
regs->tpc = regs->tnpc;
regs->tnpc += 4;
}
/* Condition codes and return value where set here for sigpause,
* and so got used by setup_frame, which again causes sigreturn()
* to return -EINTR.
*/
while (1) {
current->state = TASK_INTERRUPTIBLE;
schedule();
/*
* Return -EINTR and set condition code here,
* so the interrupted system call actually returns
* these.
*/
regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
regs->u_regs[UREG_I0] = EINTR;
if (do_signal(&saveset, regs, 0, 0))
return;
}
}
asmlinkage void do_sigpause(unsigned int set, struct pt_regs *regs)
{
_sigpause_common(set, regs);
}
asmlinkage void do_sigsuspend(struct pt_regs *regs)
{
_sigpause_common(regs->u_regs[UREG_I0], regs);
}
asmlinkage void do_rt_sigsuspend(sigset_t __user *uset, size_t sigsetsize, struct pt_regs *regs)
{
sigset_t oldset, set;
/* XXX: Don't preclude handling different sized sigset_t's. */
if (sigsetsize != sizeof(sigset_t)) {
regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
regs->u_regs[UREG_I0] = EINVAL;
return;
}
if (copy_from_user(&set, uset, sizeof(set))) {
regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
regs->u_regs[UREG_I0] = EFAULT;
return;
}
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
oldset = current->blocked;
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
if (test_thread_flag(TIF_32BIT)) {
regs->tpc = (regs->tnpc & 0xffffffff);
regs->tnpc = (regs->tnpc + 4) & 0xffffffff;
} else {
regs->tpc = regs->tnpc;
regs->tnpc += 4;
}
/* Condition codes and return value where set here for sigpause,
* and so got used by setup_frame, which again causes sigreturn()
* to return -EINTR.
*/
while (1) {
current->state = TASK_INTERRUPTIBLE;
schedule();
/*
* Return -EINTR and set condition code here,
* so the interrupted system call actually returns
* these.
*/
regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
regs->u_regs[UREG_I0] = EINTR;
if (do_signal(&oldset, regs, 0, 0))
return;
}
}
static inline int
restore_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
{
unsigned long *fpregs = current_thread_info()->fpregs;
unsigned long fprs;
int err;
err = __get_user(fprs, &fpu->si_fprs);
fprs_write(0);
regs->tstate &= ~TSTATE_PEF;
if (fprs & FPRS_DL)
err |= copy_from_user(fpregs, &fpu->si_float_regs[0],
(sizeof(unsigned int) * 32));
if (fprs & FPRS_DU)
err |= copy_from_user(fpregs+16, &fpu->si_float_regs[32],
(sizeof(unsigned int) * 32));
err |= __get_user(current_thread_info()->xfsr[0], &fpu->si_fsr);
err |= __get_user(current_thread_info()->gsr[0], &fpu->si_gsr);
current_thread_info()->fpsaved[0] |= fprs;
return err;
}
void do_rt_sigreturn(struct pt_regs *regs)
{
struct rt_signal_frame __user *sf;
unsigned long tpc, tnpc, tstate;
__siginfo_fpu_t __user *fpu_save;
mm_segment_t old_fs;
sigset_t set;
stack_t st;
int err;
/* Always make any pending restarted system calls return -EINTR */
current_thread_info()->restart_block.fn = do_no_restart_syscall;
synchronize_user_stack ();
sf = (struct rt_signal_frame __user *)
(regs->u_regs [UREG_FP] + STACK_BIAS);
/* 1. Make sure we are not getting garbage from the user */
if (((unsigned long) sf) & 3)
goto segv;
err = get_user(tpc, &sf->regs.tpc);
err |= __get_user(tnpc, &sf->regs.tnpc);
if (test_thread_flag(TIF_32BIT)) {
tpc &= 0xffffffff;
tnpc &= 0xffffffff;
}
err |= ((tpc | tnpc) & 3);
/* 2. Restore the state */
err |= __get_user(regs->y, &sf->regs.y);
err |= __get_user(tstate, &sf->regs.tstate);
err |= copy_from_user(regs->u_regs, sf->regs.u_regs, sizeof(regs->u_regs));
/* User can only change condition codes and %asi in %tstate. */
regs->tstate &= ~(TSTATE_ASI | TSTATE_ICC | TSTATE_XCC);
regs->tstate |= (tstate & (TSTATE_ASI | TSTATE_ICC | TSTATE_XCC));
err |= __get_user(fpu_save, &sf->fpu_save);
if (fpu_save)
err |= restore_fpu_state(regs, &sf->fpu_state);
err |= __copy_from_user(&set, &sf->mask, sizeof(sigset_t));
err |= __copy_from_user(&st, &sf->stack, sizeof(stack_t));
if (err)
goto segv;
regs->tpc = tpc;
regs->tnpc = tnpc;
/* It is more difficult to avoid calling this function than to
call it and ignore errors. */
old_fs = get_fs();
set_fs(KERNEL_DS);
do_sigaltstack((const stack_t __user *) &st, NULL, (unsigned long)sf);
set_fs(old_fs);
sigdelsetmask(&set, ~_BLOCKABLE);
spin_lock_irq(&current->sighand->siglock);
current->blocked = set;
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
return;
segv:
force_sig(SIGSEGV, current);
}
/* Checks if the fp is valid */
static int invalid_frame_pointer(void __user *fp, int fplen)
{
if (((unsigned long) fp) & 7)
return 1;
return 0;
}
static inline int
save_fpu_state(struct pt_regs *regs, __siginfo_fpu_t __user *fpu)
{
unsigned long *fpregs = (unsigned long *)(regs+1);
unsigned long fprs;
int err = 0;
fprs = current_thread_info()->fpsaved[0];
if (fprs & FPRS_DL)
err |= copy_to_user(&fpu->si_float_regs[0], fpregs,
(sizeof(unsigned int) * 32));
if (fprs & FPRS_DU)
err |= copy_to_user(&fpu->si_float_regs[32], fpregs+16,
(sizeof(unsigned int) * 32));
err |= __put_user(current_thread_info()->xfsr[0], &fpu->si_fsr);
err |= __put_user(current_thread_info()->gsr[0], &fpu->si_gsr);
err |= __put_user(fprs, &fpu->si_fprs);
return err;
}
static inline void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, unsigned long framesize)
{
unsigned long sp;
sp = regs->u_regs[UREG_FP] + STACK_BIAS;
/* This is the X/Open sanctioned signal stack switching. */
if (ka->sa.sa_flags & SA_ONSTACK) {
if (!on_sig_stack(sp) &&
!((current->sas_ss_sp + current->sas_ss_size) & 7))
sp = current->sas_ss_sp + current->sas_ss_size;
}
return (void __user *)(sp - framesize);
}
static inline void
setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
int signo, sigset_t *oldset, siginfo_t *info)
{
struct rt_signal_frame __user *sf;
int sigframe_size, err;
/* 1. Make sure everything is clean */
synchronize_user_stack();
save_and_clear_fpu();
sigframe_size = RT_ALIGNEDSZ;
if (!(current_thread_info()->fpsaved[0] & FPRS_FEF))
sigframe_size -= sizeof(__siginfo_fpu_t);
sf = (struct rt_signal_frame __user *)
get_sigframe(ka, regs, sigframe_size);
if (invalid_frame_pointer (sf, sigframe_size))
goto sigill;
if (get_thread_wsaved() != 0)
goto sigill;
/* 2. Save the current process state */
err = copy_to_user(&sf->regs, regs, sizeof (*regs));
if (current_thread_info()->fpsaved[0] & FPRS_FEF) {
err |= save_fpu_state(regs, &sf->fpu_state);
err |= __put_user((u64)&sf->fpu_state, &sf->fpu_save);
} else {
err |= __put_user(0, &sf->fpu_save);
}
/* Setup sigaltstack */
err |= __put_user(current->sas_ss_sp, &sf->stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->u_regs[UREG_FP]), &sf->stack.ss_flags);
err |= __put_user(current->sas_ss_size, &sf->stack.ss_size);
err |= copy_to_user(&sf->mask, oldset, sizeof(sigset_t));
err |= copy_in_user((u64 __user *)sf,
(u64 __user *)(regs->u_regs[UREG_FP]+STACK_BIAS),
sizeof(struct reg_window));
if (info)
err |= copy_siginfo_to_user(&sf->info, info);
else {
err |= __put_user(signo, &sf->info.si_signo);
err |= __put_user(SI_NOINFO, &sf->info.si_code);
}
if (err)
goto sigsegv;
/* 3. signal handler back-trampoline and parameters */
regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS;
regs->u_regs[UREG_I0] = signo;
regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
/* The sigcontext is passed in this way because of how it
* is defined in GLIBC's /usr/include/bits/sigcontext.h
* for sparc64. It includes the 128 bytes of siginfo_t.
*/
regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
/* 5. signal handler */
regs->tpc = (unsigned long) ka->sa.sa_handler;
regs->tnpc = (regs->tpc + 4);
if (test_thread_flag(TIF_32BIT)) {
regs->tpc &= 0xffffffff;
regs->tnpc &= 0xffffffff;
}
/* 4. return to kernel instructions */
regs->u_regs[UREG_I7] = (unsigned long)ka->ka_restorer;
return;
sigill:
do_exit(SIGILL);
sigsegv:
force_sigsegv(signo, current);
}
static inline void handle_signal(unsigned long signr, struct k_sigaction *ka,
siginfo_t *info,
sigset_t *oldset, struct pt_regs *regs)
{
setup_rt_frame(ka, regs, signr, oldset,
(ka->sa.sa_flags & SA_SIGINFO) ? info : NULL);
spin_lock_irq(&current->sighand->siglock);
sigorsets(&current->blocked,&current->blocked,&ka->sa.sa_mask);
if (!(ka->sa.sa_flags & SA_NOMASK))
sigaddset(&current->blocked,signr);
recalc_sigpending();
spin_unlock_irq(&current->sighand->siglock);
}
static inline void syscall_restart(unsigned long orig_i0, struct pt_regs *regs,
struct sigaction *sa)
{
switch (regs->u_regs[UREG_I0]) {
case ERESTART_RESTARTBLOCK:
case ERESTARTNOHAND:
no_system_call_restart:
regs->u_regs[UREG_I0] = EINTR;
regs->tstate |= (TSTATE_ICARRY|TSTATE_XCARRY);
break;
case ERESTARTSYS:
if (!(sa->sa_flags & SA_RESTART))
goto no_system_call_restart;
/* fallthrough */
case ERESTARTNOINTR:
regs->u_regs[UREG_I0] = orig_i0;
regs->tpc -= 4;
regs->tnpc -= 4;
}
}
/* 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.
*/
static int do_signal(sigset_t *oldset, struct pt_regs * regs,
unsigned long orig_i0, int restart_syscall)
{
siginfo_t info;
struct signal_deliver_cookie cookie;
struct k_sigaction ka;
int signr;
cookie.restart_syscall = restart_syscall;
cookie.orig_i0 = orig_i0;
if (!oldset)
oldset = &current->blocked;
#ifdef CONFIG_SPARC32_COMPAT
if (test_thread_flag(TIF_32BIT)) {
extern int do_signal32(sigset_t *, struct pt_regs *,
unsigned long, int);
return do_signal32(oldset, regs, orig_i0,
cookie.restart_syscall);
}
#endif
signr = get_signal_to_deliver(&info, &ka, regs, &cookie);
if (signr > 0) {
if (cookie.restart_syscall)
syscall_restart(orig_i0, regs, &ka.sa);
handle_signal(signr, &ka, &info, oldset, regs);
return 1;
}
if (cookie.restart_syscall &&
(regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
regs->u_regs[UREG_I0] == ERESTARTSYS ||
regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
/* replay the system call when we are done */
regs->u_regs[UREG_I0] = cookie.orig_i0;
regs->tpc -= 4;
regs->tnpc -= 4;
}
if (cookie.restart_syscall &&
regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
regs->u_regs[UREG_G1] = __NR_restart_syscall;
regs->tpc -= 4;
regs->tnpc -= 4;
}
return 0;
}
void do_notify_resume(sigset_t *oldset, struct pt_regs *regs,
unsigned long orig_i0, int restart_syscall,
unsigned long thread_info_flags)
{
if (thread_info_flags & _TIF_SIGPENDING)
do_signal(oldset, regs, orig_i0, restart_syscall);
}
void ptrace_signal_deliver(struct pt_regs *regs, void *cookie)
{
struct signal_deliver_cookie *cp = cookie;
if (cp->restart_syscall &&
(regs->u_regs[UREG_I0] == ERESTARTNOHAND ||
regs->u_regs[UREG_I0] == ERESTARTSYS ||
regs->u_regs[UREG_I0] == ERESTARTNOINTR)) {
/* replay the system call when we are done */
regs->u_regs[UREG_I0] = cp->orig_i0;
regs->tpc -= 4;
regs->tnpc -= 4;
cp->restart_syscall = 0;
}
if (cp->restart_syscall &&
regs->u_regs[UREG_I0] == ERESTART_RESTARTBLOCK) {
regs->u_regs[UREG_G1] = __NR_restart_syscall;
regs->tpc -= 4;
regs->tnpc -= 4;
cp->restart_syscall = 0;
}
}