OpenE2K/linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
4c3181bd3b
linux/arch/score/kernel/signal.c
Matt Fleming 4c3181bd3b score: use set_current_blocked() and block_sigmask() 
As described in e6fa16ab ("signal: sigprocmask() should do
retarget_shared_pending()") the modification of current->blocked is
incorrect as we need to check whether the signal we're about to block is
pending in the shared queue.

Also, use the new helper function introduced in commit 5e6292c0f2
("signal: add block_sigmask() for adding sigmask to current->blocked")
which centralises the code for updating current->blocked after
successfully delivering a signal and reduces the amount of duplicate code
across architectures.  In the past some architectures got this code wrong,
so using this helper function should stop that from happening again.

Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-21 23:52:33 -04:00

355 lines
9.6 KiB
C
Raw Blame History

/*
* arch/score/kernel/signal.c
*
* Score Processor version.
*
* Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
* Chen Liqin <liqin.chen@sunplusct.com>
* Lennox Wu <lennox.wu@sunplusct.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/ptrace.h>
#include <linux/unistd.h>
#include <linux/uaccess.h>
#include <asm/cacheflush.h>
#include <asm/syscalls.h>
#include <asm/ucontext.h>
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
struct rt_sigframe {
u32 rs_ass[4]; /* argument save space */
u32 rs_code[2]; /* signal trampoline */
struct siginfo rs_info;
struct ucontext rs_uc;
};
static int setup_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
int err = 0;
unsigned long reg;
reg = regs->cp0_epc; err |= __put_user(reg, &sc->sc_pc);
err |= __put_user(regs->cp0_psr, &sc->sc_psr);
err |= __put_user(regs->cp0_condition, &sc->sc_condition);
#define save_gp_reg(i) { \
reg = regs->regs[i]; \
err |= __put_user(reg, &sc->sc_regs[i]); \
} while (0)
save_gp_reg(0); save_gp_reg(1); save_gp_reg(2);
save_gp_reg(3); save_gp_reg(4); save_gp_reg(5);
save_gp_reg(6); save_gp_reg(7); save_gp_reg(8);
save_gp_reg(9); save_gp_reg(10); save_gp_reg(11);
save_gp_reg(12); save_gp_reg(13); save_gp_reg(14);
save_gp_reg(15); save_gp_reg(16); save_gp_reg(17);
save_gp_reg(18); save_gp_reg(19); save_gp_reg(20);
save_gp_reg(21); save_gp_reg(22); save_gp_reg(23);
save_gp_reg(24); save_gp_reg(25); save_gp_reg(26);
save_gp_reg(27); save_gp_reg(28); save_gp_reg(29);
#undef save_gp_reg
reg = regs->ceh; err |= __put_user(reg, &sc->sc_mdceh);
reg = regs->cel; err |= __put_user(reg, &sc->sc_mdcel);
err |= __put_user(regs->cp0_ecr, &sc->sc_ecr);
err |= __put_user(regs->cp0_ema, &sc->sc_ema);
return err;
}
static int restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
int err = 0;
u32 reg;
err |= __get_user(regs->cp0_epc, &sc->sc_pc);
err |= __get_user(regs->cp0_condition, &sc->sc_condition);
err |= __get_user(reg, &sc->sc_mdceh);
regs->ceh = (int) reg;
err |= __get_user(reg, &sc->sc_mdcel);
regs->cel = (int) reg;
err |= __get_user(reg, &sc->sc_psr);
regs->cp0_psr = (int) reg;
err |= __get_user(reg, &sc->sc_ecr);
regs->cp0_ecr = (int) reg;
err |= __get_user(reg, &sc->sc_ema);
regs->cp0_ema = (int) reg;
#define restore_gp_reg(i) do { \
err |= __get_user(reg, &sc->sc_regs[i]); \
regs->regs[i] = reg; \
} while (0)
restore_gp_reg(0); restore_gp_reg(1); restore_gp_reg(2);
restore_gp_reg(3); restore_gp_reg(4); restore_gp_reg(5);
restore_gp_reg(6); restore_gp_reg(7); restore_gp_reg(8);
restore_gp_reg(9); restore_gp_reg(10); restore_gp_reg(11);
restore_gp_reg(12); restore_gp_reg(13); restore_gp_reg(14);
restore_gp_reg(15); restore_gp_reg(16); restore_gp_reg(17);
restore_gp_reg(18); restore_gp_reg(19); restore_gp_reg(20);
restore_gp_reg(21); restore_gp_reg(22); restore_gp_reg(23);
restore_gp_reg(24); restore_gp_reg(25); restore_gp_reg(26);
restore_gp_reg(27); restore_gp_reg(28); restore_gp_reg(29);
#undef restore_gp_reg
return err;
}
/*
* Determine which stack to use..
*/
static void __user *get_sigframe(struct k_sigaction *ka,
struct pt_regs *regs, size_t frame_size)
{
unsigned long sp;
/* Default to using normal stack */
sp = regs->regs[0];
sp -= 32;
/* This is the X/Open sanctioned signal stack switching. */
if ((ka->sa.sa_flags & SA_ONSTACK) && (!on_sig_stack(sp)))
sp = current->sas_ss_sp + current->sas_ss_size;
return (void __user*)((sp - frame_size) & ~7);
}
asmlinkage long
score_sigaltstack(struct pt_regs *regs)
{
const stack_t __user *uss = (const stack_t __user *) regs->regs[4];
stack_t __user *uoss = (stack_t __user *) regs->regs[5];
unsigned long usp = regs->regs[0];
return do_sigaltstack(uss, uoss, usp);
}
asmlinkage long
score_rt_sigreturn(struct pt_regs *regs)
{
struct rt_sigframe __user *frame;
sigset_t set;
stack_t st;
int sig;
frame = (struct rt_sigframe __user *) regs->regs[0];
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__copy_from_user(&set, &frame->rs_uc.uc_sigmask, sizeof(set)))
goto badframe;
sigdelsetmask(&set, ~_BLOCKABLE);
set_current_blocked(&set);
sig = restore_sigcontext(regs, &frame->rs_uc.uc_mcontext);
if (sig < 0)
goto badframe;
else if (sig)
force_sig(sig, current);
if (__copy_from_user(&st, &frame->rs_uc.uc_stack, sizeof(st)))
goto badframe;
/* It is more difficult to avoid calling this function than to
call it and ignore errors. */
do_sigaltstack((stack_t __user *)&st, NULL, regs->regs[0]);
__asm__ __volatile__(
"mv\tr0, %0\n\t"
"la\tr8, syscall_exit\n\t"
"br\tr8\n\t"
: : "r" (regs) : "r8");
badframe:
force_sig(SIGSEGV, current);
return 0;
}
static int setup_rt_frame(struct k_sigaction *ka, struct pt_regs *regs,
int signr, sigset_t *set, siginfo_t *info)
{
struct rt_sigframe __user *frame;
int err = 0;
frame = get_sigframe(ka, regs, sizeof(*frame));
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
/*
* Set up the return code ...
*
* li v0, __NR_rt_sigreturn
* syscall
*/
err |= __put_user(0x87788000 + __NR_rt_sigreturn*2,
frame->rs_code + 0);
err |= __put_user(0x80008002, frame->rs_code + 1);
flush_cache_sigtramp((unsigned long) frame->rs_code);
err |= copy_siginfo_to_user(&frame->rs_info, info);
err |= __put_user(0, &frame->rs_uc.uc_flags);
err |= __put_user(NULL, &frame->rs_uc.uc_link);
err |= __put_user((void __user *)current->sas_ss_sp,
&frame->rs_uc.uc_stack.ss_sp);
err |= __put_user(sas_ss_flags(regs->regs[0]),
&frame->rs_uc.uc_stack.ss_flags);
err |= __put_user(current->sas_ss_size,
&frame->rs_uc.uc_stack.ss_size);
err |= setup_sigcontext(regs, &frame->rs_uc.uc_mcontext);
err |= __copy_to_user(&frame->rs_uc.uc_sigmask, set, sizeof(*set));
if (err)
goto give_sigsegv;
regs->regs[0] = (unsigned long) frame;
regs->regs[3] = (unsigned long) frame->rs_code;
regs->regs[4] = signr;
regs->regs[5] = (unsigned long) &frame->rs_info;
regs->regs[6] = (unsigned long) &frame->rs_uc;
regs->regs[29] = (unsigned long) ka->sa.sa_handler;
regs->cp0_epc = (unsigned long) ka->sa.sa_handler;
return 0;
give_sigsegv:
if (signr == SIGSEGV)
ka->sa.sa_handler = SIG_DFL;
force_sig(SIGSEGV, current);
return -EFAULT;
}
static int handle_signal(unsigned long sig, siginfo_t *info,
struct k_sigaction *ka, sigset_t *oldset, struct pt_regs *regs)
{
int ret;
if (regs->is_syscall) {
switch (regs->regs[4]) {
case ERESTART_RESTARTBLOCK:
case ERESTARTNOHAND:
regs->regs[4] = EINTR;
break;
case ERESTARTSYS:
if (!(ka->sa.sa_flags & SA_RESTART)) {
regs->regs[4] = EINTR;
break;
}
case ERESTARTNOINTR:
regs->regs[4] = regs->orig_r4;
regs->regs[7] = regs->orig_r7;
regs->cp0_epc -= 8;
}
regs->is_syscall = 0;
}
/*
* Set up the stack frame
*/
ret = setup_rt_frame(ka, regs, sig, oldset, info);
if (ret == 0)
block_sigmask(ka, sig);
return ret;
}
static void do_signal(struct pt_regs *regs)
{
struct k_sigaction ka;
sigset_t *oldset;
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;
if (test_thread_flag(TIF_RESTORE_SIGMASK))
oldset = &current->saved_sigmask;
else
oldset = &current->blocked;
signr = get_signal_to_deliver(&info, &ka, regs, NULL);
if (signr > 0) {
/* Actually deliver the signal. */
if (handle_signal(signr, &info, &ka, oldset, regs) == 0) {
/*
* A signal was successfully delivered; the saved
* sigmask will have been stored in the signal frame,
* and will be restored by sigreturn, so we can simply
* clear the TIF_RESTORE_SIGMASK flag.
*/
if (test_thread_flag(TIF_RESTORE_SIGMASK))
clear_thread_flag(TIF_RESTORE_SIGMASK);
}
return;
}
if (regs->is_syscall) {
if (regs->regs[4] == ERESTARTNOHAND ||
regs->regs[4] == ERESTARTSYS ||
regs->regs[4] == ERESTARTNOINTR) {
regs->regs[4] = regs->orig_r4;
regs->regs[7] = regs->orig_r7;
regs->cp0_epc -= 8;
}
if (regs->regs[4] == ERESTART_RESTARTBLOCK) {
regs->regs[27] = __NR_restart_syscall;
regs->regs[4] = regs->orig_r4;
regs->regs[7] = regs->orig_r7;
regs->cp0_epc -= 8;
}
regs->is_syscall = 0; /* Don't deal with this again. */
}
/*
* If there's no signal to deliver, we just put the saved sigmask
* back
*/
if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
clear_thread_flag(TIF_RESTORE_SIGMASK);
sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
}
}
/*
* notification of userspace execution resumption
* - triggered by the TIF_WORK_MASK flags
*/
asmlinkage void do_notify_resume(struct pt_regs *regs, void *unused,
__u32 thread_info_flags)
{
/* deal with pending signal delivery */
if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
do_signal(regs);
}
Reference in New Issue View Git Blame Copy Permalink