Commit fef2b580 authored by David Howells's avatar David Howells Committed by Linus Torvalds
Browse files

[PATCH] frv: improve signal handling 



The attached patch improves the signal handling:

 (1) It makes do_signal() static as it isn't called from anywhere outside of
     the arch code.

 (2) It removes the regs argument to all the static functions within that file,
     using __frame instead (which is the same thing held in a global register).

Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 8efc0ab5

arch/frv/kernel/signal.c

+50 −52
Original line number Diff line number Diff line
@@ -35,7 +35,7 @@ struct fdpic_func_descriptor { 
	unsigned long	GOT;

};



asmlinkage int do_signal(struct pt_regs *regs, sigset_t *oldset);

static int do_signal(sigset_t *oldset);



/*

 * Atomically swap in the new signal mask, and wait for a signal.
@@ -55,7 +55,7 @@ asmlinkage int sys_sigsuspend(int history0, int history1, old_sigset_t mask) 
	while (1) {

		current->state = TASK_INTERRUPTIBLE;

		schedule();

		if (do_signal(__frame, &saveset))

		if (do_signal(&saveset))

			/* return the signal number as the return value of this function

			 * - this is an utterly evil hack. syscalls should not invoke do_signal()

			 *   as entry.S sets regs->gr8 to the return value of the system call
@@ -91,7 +91,7 @@ asmlinkage int sys_rt_sigsuspend(sigset_t __user *unewset, size_t sigsetsize) 
	while (1) {

		current->state = TASK_INTERRUPTIBLE;

		schedule();

		if (do_signal(__frame, &saveset))

		if (do_signal(&saveset))

			/* return the signal number as the return value of this function

			 * - this is an utterly evil hack. syscalls should not invoke do_signal()

			 *   as entry.S sets regs->gr8 to the return value of the system call
@@ -276,13 +276,12 @@ static int setup_sigcontext(struct sigcontext __user *sc, unsigned long mask) 
 * Determine which stack to use..

 */

static inline 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->sp;

	sp = __frame->sp;



	/* This is the X/Open sanctioned signal stack switching.  */

	if (ka->sa.sa_flags & SA_ONSTACK) {
@@ -291,19 +290,19 @@ static inline void __user *get_sigframe(struct k_sigaction *ka, 
	}



	return (void __user *) ((sp - frame_size) & ~7UL);



} /* end get_sigframe() */



/*****************************************************************************/

/*

 *

 */

static int setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,

		       struct pt_regs *regs)

static int setup_frame(int sig, struct k_sigaction *ka, sigset_t *set)

{

	struct sigframe __user *frame;

	int rsig;



	frame = get_sigframe(ka, regs, sizeof(*frame));

	frame = get_sigframe(ka, sizeof(*frame));



	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))

		goto give_sigsegv;
@@ -347,18 +346,18 @@ static int setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, 
	}



	/* set up registers for signal handler */

	regs->sp   = (unsigned long) frame;

	regs->lr   = (unsigned long) &frame->retcode;

	regs->gr8  = sig;

	__frame->sp   = (unsigned long) frame;

	__frame->lr   = (unsigned long) &frame->retcode;

	__frame->gr8  = sig;



	if (get_personality & FDPIC_FUNCPTRS) {

		struct fdpic_func_descriptor __user *funcptr =

			(struct fdpic_func_descriptor *) ka->sa.sa_handler;

		__get_user(regs->pc, &funcptr->text);

		__get_user(regs->gr15, &funcptr->GOT);

		__get_user(__frame->pc, &funcptr->text);

		__get_user(__frame->gr15, &funcptr->GOT);

	} else {

		regs->pc   = (unsigned long) ka->sa.sa_handler;

		regs->gr15 = 0;

		__frame->pc   = (unsigned long) ka->sa.sa_handler;

		__frame->gr15 = 0;

	}



	set_fs(USER_DS);
@@ -369,7 +368,7 @@ static int setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, 


#if DEBUG_SIG

	printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",

	       sig, current->comm, current->pid, frame, regs->pc,

	       sig, current->comm, current->pid, frame, __frame->pc,

	       frame->pretcode);

#endif
@@ -386,12 +385,12 @@ give_sigsegv: 
 *

 */

static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,

			  sigset_t *set, struct pt_regs * regs)

			  sigset_t *set)

{

	struct rt_sigframe __user *frame;

	int rsig;



	frame = get_sigframe(ka, regs, sizeof(*frame));

	frame = get_sigframe(ka, sizeof(*frame));



	if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))

		goto give_sigsegv;
@@ -414,7 +413,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, 
	if (__put_user(0, &frame->uc.uc_flags) ||

	    __put_user(0, &frame->uc.uc_link) ||

	    __put_user((void*)current->sas_ss_sp, &frame->uc.uc_stack.ss_sp) ||

	    __put_user(sas_ss_flags(regs->sp), &frame->uc.uc_stack.ss_flags) ||

	    __put_user(sas_ss_flags(__frame->sp), &frame->uc.uc_stack.ss_flags) ||

	    __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size))

		goto give_sigsegv;
@@ -445,19 +444,19 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, 
	}



	/* Set up registers for signal handler */

	regs->sp  = (unsigned long) frame;

	regs->lr   = (unsigned long) &frame->retcode;

	regs->gr8 = sig;

	regs->gr9 = (unsigned long) &frame->info;

	__frame->sp  = (unsigned long) frame;

	__frame->lr   = (unsigned long) &frame->retcode;

	__frame->gr8 = sig;

	__frame->gr9 = (unsigned long) &frame->info;



	if (get_personality & FDPIC_FUNCPTRS) {

		struct fdpic_func_descriptor *funcptr =

			(struct fdpic_func_descriptor __user *) ka->sa.sa_handler;

		__get_user(regs->pc, &funcptr->text);

		__get_user(regs->gr15, &funcptr->GOT);

		__get_user(__frame->pc, &funcptr->text);

		__get_user(__frame->gr15, &funcptr->GOT);

	} else {

		regs->pc   = (unsigned long) ka->sa.sa_handler;

		regs->gr15 = 0;

		__frame->pc   = (unsigned long) ka->sa.sa_handler;

		__frame->gr15 = 0;

	}



	set_fs(USER_DS);
@@ -468,7 +467,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, 


#if DEBUG_SIG

	printk("SIG deliver %d (%s:%d): sp=%p pc=%lx ra=%p\n",

		sig, current->comm, current->pid, frame, regs->pc,

	       sig, current->comm, current->pid, frame, __frame->pc,

	       frame->pretcode);

#endif
@@ -485,38 +484,37 @@ give_sigsegv: 
 * OK, we're invoking a handler

 */

static int handle_signal(unsigned long sig, siginfo_t *info,

			 struct k_sigaction *ka, sigset_t *oldset,

			 struct pt_regs *regs)

			 struct k_sigaction *ka, sigset_t *oldset)

{

	int ret;



	/* Are we from a system call? */

	if (in_syscall(regs)) {

	if (in_syscall(__frame)) {

		/* If so, check system call restarting.. */

		switch (regs->gr8) {

		switch (__frame->gr8) {

		case -ERESTART_RESTARTBLOCK:

		case -ERESTARTNOHAND:

			regs->gr8 = -EINTR;

			__frame->gr8 = -EINTR;

			break;



		case -ERESTARTSYS:

			if (!(ka->sa.sa_flags & SA_RESTART)) {

				regs->gr8 = -EINTR;

				__frame->gr8 = -EINTR;

				break;

			}



			/* fallthrough */

		case -ERESTARTNOINTR:

			regs->gr8 = regs->orig_gr8;

			regs->pc -= 4;

			__frame->gr8 = __frame->orig_gr8;

			__frame->pc -= 4;

		}

	}



	/* Set up the stack frame */

	if (ka->sa.sa_flags & SA_SIGINFO)

		ret = setup_rt_frame(sig, ka, info, oldset, regs);

		ret = setup_rt_frame(sig, ka, info, oldset);

	else

		ret = setup_frame(sig, ka, oldset, regs);

		ret = setup_frame(sig, ka, oldset);



	if (ret) {

		spin_lock_irq(&current->sighand->siglock);
@@ -538,7 +536,7 @@ static int handle_signal(unsigned long sig, siginfo_t *info, 
 * want to handle. Thus you cannot kill init even with a SIGKILL even by

 * mistake.

 */

int do_signal(struct pt_regs *regs, sigset_t *oldset)

static int do_signal(sigset_t *oldset)

{

	struct k_sigaction ka;

	siginfo_t info;
@@ -550,7 +548,7 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset) 
	 * kernel mode. Just return without doing anything

	 * if so.

	 */

	if (!user_mode(regs))

	if (!user_mode(__frame))

		return 1;



	if (try_to_freeze())
@@ -559,24 +557,24 @@ int do_signal(struct pt_regs *regs, sigset_t *oldset) 
	if (!oldset)

		oldset = &current->blocked;



	signr = get_signal_to_deliver(&info, &ka, regs, NULL);

	signr = get_signal_to_deliver(&info, &ka, __frame, NULL);

	if (signr > 0)

		return handle_signal(signr, &info, &ka, oldset, regs);

		return handle_signal(signr, &info, &ka, oldset);



no_signal:

	/* Did we come from a system call? */

	if (regs->syscallno >= 0) {

	if (__frame->syscallno >= 0) {

		/* Restart the system call - no handlers present */

		if (regs->gr8 == -ERESTARTNOHAND ||

		    regs->gr8 == -ERESTARTSYS ||

		    regs->gr8 == -ERESTARTNOINTR) {

			regs->gr8 = regs->orig_gr8;

			regs->pc -= 4;

		if (__frame->gr8 == -ERESTARTNOHAND ||

		    __frame->gr8 == -ERESTARTSYS ||

		    __frame->gr8 == -ERESTARTNOINTR) {

			__frame->gr8 = __frame->orig_gr8;

			__frame->pc -= 4;

		}



		if (regs->gr8 == -ERESTART_RESTARTBLOCK){

			regs->gr8 = __NR_restart_syscall;

			regs->pc -= 4;

		if (__frame->gr8 == -ERESTART_RESTARTBLOCK){

			__frame->gr8 = __NR_restart_syscall;

			__frame->pc -= 4;

		}

	}
@@ -597,6 +595,6 @@ asmlinkage void do_notify_resume(__u32 thread_info_flags) 


	/* deal with pending signal delivery */

	if (thread_info_flags & _TIF_SIGPENDING)

		do_signal(__frame, NULL);

		do_signal(NULL);



} /* end do_notify_resume() */

include/asm-frv/signal.h

+0 −1
Original line number Diff line number Diff line
@@ -151,7 +151,6 @@ typedef struct sigaltstack { 
	size_t ss_size;

} stack_t;



extern int do_signal(struct pt_regs *regs, sigset_t *oldset);

#define ptrace_signal_deliver(regs, cookie) do { } while (0)



#ifdef __KERNEL__

CRA Git | Maintained and supported by SUSTech CRA and CCSE