[PATCH 2/6] m68k: switch to saner sigsuspend()

Al Viro
2010-10-07T17:09:34Z

and saner do_signal() arguments, while we are at it

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
arch/m68k/include/asm/thread_info_mm.h | 1 +
arch/m68k/include/asm/unistd.h | 1 +
arch/m68k/kernel/entry.S | 19 +---------
arch/m68k/kernel/signal.c | 64 ++++++++++---------------------
4 files changed, 24 insertions(+), 61 deletions(-)

diff --git a/arch/m68k/include/asm/thread_info_mm.h b/arch/m68k/include/asm/thread_info_mm.h
index 3bf31dc..b2ea8be 100644
--- a/arch/m68k/include/asm/thread_info_mm.h
+++ b/arch/m68k/include/asm/thread_info_mm.h
@@ -67,5 +67,6 @@ struct thread_info {
#define TIF_SYSCALL_TRACE 15 /* syscall trace active */
#define TIF_MEMDIE 16 /* is terminating due to OOM killer */
#define TIF_FREEZE 17 /* thread is freezing for suspend */
+#define TIF_RESTORE_SIGMASK 18 /* restore signal mask in do_signal */

#endif /* _ASM_M68K_THREAD_INFO_H */
diff --git a/arch/m68k/include/asm/unistd.h b/arch/m68k/include/asm/unistd.h
index b43b36b..26d851d 100644
--- a/arch/m68k/include/asm/unistd.h
+++ b/arch/m68k/include/asm/unistd.h
@@ -373,6 +373,7 @@
#define __ARCH_WANT_SYS_SIGPENDING
#define __ARCH_WANT_SYS_SIGPROCMASK
#define __ARCH_WANT_SYS_RT_SIGACTION
+#define __ARCH_WANT_SYS_RT_SIGSUSPEND

/*
* "Conditional" syscalls
diff --git a/arch/m68k/kernel/entry.S b/arch/m68k/kernel/entry.S
index 6360c43..3a15a03 100644
--- a/arch/m68k/kernel/entry.S
+++ b/arch/m68k/kernel/entry.S
@@ -174,9 +174,8 @@ do_signal_return:
subql #4,%sp | dummy return address
SAVE_SWITCH_STACK
pea %sp@(SWITCH_STACK_SIZE)
- clrl %sp@-
bsrl do_signal
- addql #8,%sp
+ addql #4,%sp
RESTORE_SWITCH_STACK
addql #4,%sp
tstl %d0
@@ -290,22 +289,6 @@ ENTRY(sys_vfork)
RESTORE_SWITCH_STACK
rts

-ENTRY(sys_sigsuspend)
- SAVE_SWITCH_STACK
- pea %sp@(SWITCH_STACK_SIZE)
- jbsr do_sigsuspend
- addql #4,%sp
- RESTORE_SWITCH_STACK
- rts
-
-ENTRY(sys_rt_sigsuspend)
- SAVE_SWITCH_STACK
- pea %sp@(SWITCH_STACK_SIZE)
- jbsr do_rt_sigsuspend
- addql #4,%sp
- RESTORE_SWITCH_STACK
- rts
-
ENTRY(sys_sigreturn)
SAVE_SWITCH_STACK
jbsr do_sigreturn
diff --git a/arch/m68k/kernel/signal.c b/arch/m68k/kernel/signal.c
index c776c81..fa8200d 100644
--- a/arch/m68k/kernel/signal.c
+++ b/arch/m68k/kernel/signal.c
@@ -51,8 +51,6 @@

#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))

-asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs);
-
const int frame_extra_sizes[16] = {
[1] = -1, /* sizeof(((struct frame *)0)->un.fmt1), */
[2] = sizeof(((struct frame *)0)->un.fmt2),
@@ -74,51 +72,21 @@ const int frame_extra_sizes[16] = {
/*
* Atomically swap in the new signal mask, and wait for a signal.
*/
-asmlinkage int do_sigsuspend(struct pt_regs *regs)
+asmlinkage int
+sys_sigsuspend(int unused0, int unused1, old_sigset_t mask)
{
- old_sigset_t mask = regs->d3;
- sigset_t saveset;
-
mask &= _BLOCKABLE;
- saveset = current->blocked;
+ spin_lock_irq(&current->sighand->siglock);
+ current->saved_sigmask = 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 __user *unewset = (sigset_t __user *)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);
-
- saveset = current->blocked;
- current->blocked = newset;
- recalc_sigpending();
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ set_restore_sigmask();

- regs->d0 = -EINTR;
- while (1) {
- current->state = TASK_INTERRUPTIBLE;
- schedule();
- if (do_signal(&saveset, regs))
- return -EINTR;
- }
+ return -ERESTARTNOHAND;
}

asmlinkage int
@@ -1017,21 +985,25 @@ handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info,
* 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)
+asmlinkage int do_signal(struct pt_regs *regs)
{
siginfo_t info;
struct k_sigaction ka;
int signr;
+ sigset_t *oldset;

current->thread.esp0 = (unsigned long) regs;

- if (!oldset)
+ 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) {
/* Whee! Actually deliver the signal. */
handle_signal(signr, &ka, &info, oldset, regs);
+ clear_thread_flag(TIF_RESTORE_SIGMASK);
return 1;
}

@@ -1040,5 +1012,11 @@ asmlinkage int do_signal(sigset_t *oldset, struct pt_regs *regs)
/* Restart the system call - no handlers present */
handle_restart(regs, NULL, 0);

+ /* If there's no signal to deliver, we just restore the saved mask. */
+ if (test_thread_flag(TIF_RESTORE_SIGMASK)) {
+ clear_thread_flag(TIF_RESTORE_SIGMASK);
+ sigprocmask(SIG_SETMASK, &current->saved_sigmask, NULL);
+ }
+
return 0;
}
--
1.5.6.5