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/*
* Copyright (C) 2003, Axis Communications AB.
*/
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/slab.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/stddef.h>
#include <linux/syscalls.h>
#include <linux/vmalloc.h>
#include <asm/io.h>
#include <asm/processor.h>
#include <asm/ucontext.h>
#include <asm/uaccess.h>
#include <arch/ptrace.h>
#include <arch/hwregs/cpu_vect.h>
extern unsigned long cris_signal_return_page;
/* Flag to check if a signal is blockable. */
#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
/*
* A syscall in CRIS is really a "break 13" instruction, which is 2
* bytes. The registers is manipulated so upon return the instruction
* will be executed again.
*
* This relies on that PC points to the instruction after the break call.
*/
#define RESTART_CRIS_SYS(regs) regs->r10 = regs->orig_r10; regs->erp -= 2;
/* Signal frames. */
struct signal_frame {
struct sigcontext sc;
unsigned long extramask[_NSIG_WORDS - 1];
unsigned char retcode[8]; /* Trampoline code. */
};
struct rt_signal_frame {
struct siginfo *pinfo;
void *puc;
struct siginfo info;
struct ucontext uc;
unsigned char retcode[8]; /* Trampoline code. */
};
void do_signal(int restart, struct pt_regs *regs);
void keep_debug_flags(unsigned long oldccs, unsigned long oldspc,
struct pt_regs *regs);
/*
* Swap in the new signal mask, and wait for a signal. Define some
* dummy arguments to be able to reach the regs argument.
*/
int
sys_sigsuspend(old_sigset_t mask)
{
sigset_t blocked;
siginitset(&blocked, mask);
return sigsuspend(&blocked);
}
int
sys_sigaction(int signal, const struct old_sigaction *act,
struct old_sigaction *oact)
{
int retval;
struct k_sigaction newk;
struct k_sigaction oldk;
if (act) {
old_sigset_t mask;
if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
__get_user(newk.sa.sa_handler, &act->sa_handler) ||
__get_user(newk.sa.sa_restorer, &act->sa_restorer) ||
__get_user(newk.sa.sa_flags, &act->sa_flags) ||
__get_user(mask, &act->sa_mask))
return -EFAULT;
siginitset(&newk.sa.sa_mask, mask);
}
retval = do_sigaction(signal, act ? &newk : NULL, oact ? &oldk : NULL);
if (!retval && oact) {
if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
__put_user(oldk.sa.sa_handler, &oact->sa_handler) ||
__put_user(oldk.sa.sa_restorer, &oact->sa_restorer) ||
__put_user(oldk.sa.sa_flags, &oact->sa_flags) ||
__put_user(oldk.sa.sa_mask.sig[0], &oact->sa_mask))
return -EFAULT;
}
return retval;
}
int
sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss)
{
return do_sigaltstack(uss, uoss, rdusp());
}
static int
restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc)
{
unsigned int err = 0;
unsigned long old_usp;
/* Always make any pending restarted system calls return -EINTR */
current_thread_info()->restart_block.fn = do_no_restart_syscall;
/*
* Restore the registers from &sc->regs. sc is already checked
* for VERIFY_READ since the signal_frame was previously
* checked in sys_sigreturn().
*/
if (__copy_from_user(regs, sc, sizeof(struct pt_regs)))
goto badframe;
/* Make that the user-mode flag is set. */
regs->ccs |= (1 << (U_CCS_BITNR + CCS_SHIFT));
/* Restore the old USP. */
err |= __get_user(old_usp, &sc->usp);
wrusp(old_usp);
return err;
badframe:
return 1;
}
/* Define some dummy arguments to be able to reach the regs argument. */
asmlinkage int
sys_sigreturn(long r10, long r11, long r12, long r13, long mof, long srp,
struct pt_regs *regs)
{
sigset_t set;
struct signal_frame __user *frame;
unsigned long oldspc = regs->spc;
unsigned long oldccs = regs->ccs;
frame = (struct signal_frame *) rdusp();
/*
* Since the signal is stacked on a dword boundary, the frame
* should be dword aligned here as well. It it's not, then the
* user is trying some funny business.
*/
if (((long)frame) & 3)
goto badframe;
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__get_user(set.sig[0], &frame->sc.oldmask) ||
(_NSIG_WORDS > 1 && __copy_from_user(&set.sig[1],
frame->extramask,
sizeof(frame->extramask))))
goto badframe;
sigdelsetmask(&set, ~_BLOCKABLE);
set_current_blocked(&set);
if (restore_sigcontext(regs, &frame->sc))
goto badframe;
keep_debug_flags(oldccs, oldspc, regs);
return regs->r10;
badframe:
force_sig(SIGSEGV, current);
return 0;
}
/* Define some dummy variables to be able to reach the regs argument. */
asmlinkage int
sys_rt_sigreturn(long r10, long r11, long r12, long r13, long mof, long srp,
struct pt_regs *regs)
{
sigset_t set;
struct rt_signal_frame __user *frame;
unsigned long oldspc = regs->spc;
unsigned long oldccs = regs->ccs;
frame = (struct rt_signal_frame *) rdusp();
/*
* Since the signal is stacked on a dword boundary, the frame
* should be dword aligned here as well. It it's not, then the
* user is trying some funny business.
*/
if (((long)frame) & 3)
goto badframe;
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);
set_current_blocked(&set);
if (restore_sigcontext(regs, &frame->uc.uc_mcontext))
goto badframe;
if (do_sigaltstack(&frame->uc.uc_stack, NULL, rdusp()) == -EFAULT)
goto badframe;
keep_debug_flags(oldccs, oldspc, regs);
return regs->r10;
badframe:
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