[PARISC] factor syscall_restart code out of do_signal

looks better this way... ;)

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>

arch/parisc/kernel/signal.c

@@ -471,6 +471,97 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
 	return 1;
 }
 
+static inline void
+syscall_restart(struct pt_regs *regs, struct k_sigaction *ka)
+{
+	/* Check the return code */
+	switch (regs->gr[28]) {
+	case -ERESTART_RESTARTBLOCK:
+		current_thread_info()->restart_block.fn =
+			do_no_restart_syscall;
+	case -ERESTARTNOHAND:
+		DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
+		regs->gr[28] = -EINTR;
+		break;
+
+	case -ERESTARTSYS:
+		if (!(ka->sa.sa_flags & SA_RESTART)) {
+			DBG(1,"ERESTARTSYS: putting -EINTR\n");
+			regs->gr[28] = -EINTR;
+			break;
+		}
+		/* fallthrough */
+	case -ERESTARTNOINTR:
+		/* A syscall is just a branch, so all
+		 * we have to do is fiddle the return pointer.
+		 */
+		regs->gr[31] -= 8; /* delayed branching */
+		/* Preserve original r28. */
+		regs->gr[28] = regs->orig_r28;
+		break;
+	}
+}
+
+static inline void
+insert_restart_trampoline(struct pt_regs *regs)
+{
+	switch(regs->gr[28]) {
+	case -ERESTART_RESTARTBLOCK: {
+		/* Restart the system call - no handlers present */
+		unsigned int *usp = (unsigned int *)regs->gr[30];
+
+		/* Setup a trampoline to restart the syscall
+		 * with __NR_restart_syscall
+		 *
+		 *  0: <return address (orig r31)>
+		 *  4: <2nd half for 64-bit>
+		 *  8: ldw 0(%sp), %r31
+		 * 12: be 0x100(%sr2, %r0)
+		 * 16: ldi __NR_restart_syscall, %r20
+		 */
+#ifdef CONFIG_64BIT
+		put_user(regs->gr[31] >> 32, &usp[0]);
+		put_user(regs->gr[31] & 0xffffffff, &usp[1]);
+		put_user(0x0fc010df, &usp[2]);
+#else
+		put_user(regs->gr[31], &usp[0]);
+		put_user(0x0fc0109f, &usp[2]);
+#endif
+		put_user(0xe0008200, &usp[3]);
+		put_user(0x34140000, &usp[4]);
+
+		/* Stack is 64-byte aligned, and we only need
+		 * to flush 1 cache line.
+		 * Flushing one cacheline is cheap.
+		 * "sync" on bigger (> 4 way) boxes is not.
+		 */
+		flush_icache_range(regs->gr[30], regs->gr[30] + 4);
+
+		regs->gr[31] = regs->gr[30] + 8;
+		/* Preserve original r28. */
+		regs->gr[28] = regs->orig_r28;
+
+		return;
+	}
+	case -ERESTARTNOHAND:
+	case -ERESTARTSYS:
+	case -ERESTARTNOINTR: {
+		/* Hooray for delayed branching.  We don't
+		 * have to restore %r20 (the system call
+		 * number) because it gets loaded in the delay
+		 * slot of the branch external instruction.
+		 */
+		regs->gr[31] -= 8;
+		/* Preserve original r28. */
+		regs->gr[28] = regs->orig_r28;
+
+		return;
+	}
+	default:
+		break;
+	}
+}
+
 /*
  * 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
@@ -482,7 +573,6 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
  * registers).  As noted below, the syscall number gets restored for
  * us due to the magic of delayed branching.
  */
-
 asmlinkage void
 do_signal(struct pt_regs *regs, long in_syscall)
 {
@@ -518,36 +608,14 @@ do_signal(struct pt_regs *regs, long in_syscall)
 		  break;
 		
 		/* Restart a system call if necessary. */
-		if (in_syscall) {
-			/* Check the return code */
-			switch (regs->gr[28]) {
-		        case -ERESTART_RESTARTBLOCK:
-				current_thread_info()->restart_block.fn = do_no_restart_syscall;
-			case -ERESTARTNOHAND:
-				DBG(1,"ERESTARTNOHAND: returning -EINTR\n");
-				regs->gr[28] = -EINTR;
-				break;
-
-			case -ERESTARTSYS:
-				if (!(ka.sa.sa_flags & SA_RESTART)) {
-					DBG(1,"ERESTARTSYS: putting -EINTR\n");
-					regs->gr[28] = -EINTR;
-					break;
-				}
-			/* fallthrough */
-			case -ERESTARTNOINTR:
-				/* A syscall is just a branch, so all
-				   we have to do is fiddle the return pointer. */
-				regs->gr[31] -= 8; /* delayed branching */
-				/* Preserve original r28. */
-				regs->gr[28] = regs->orig_r28;
-				break;
-			}
-		}
+		if (in_syscall)
+			syscall_restart(regs, &ka);
+
 		/* Whee!  Actually deliver the signal.  If the
 		   delivery failed, we need to continue to iterate in
 		   this loop so we can deliver the SIGSEGV... */
-		if (handle_signal(signr, &info, &ka, oldset, regs, in_syscall)) {
+		if (handle_signal(signr, &info, &ka, oldset,
+				  regs, in_syscall)) {
 			DBG(1,KERN_DEBUG "do_signal: Exit (success), regs->gr[28] = %ld\n",
 				regs->gr[28]);
 			if (test_thread_flag(TIF_RESTORE_SIGMASK))
@@ -558,57 +626,8 @@ do_signal(struct pt_regs *regs, long in_syscall)
 	/* end of while(1) looping forever if we can't force a signal */
 
 	/* Did we come from a system call? */
-	if (in_syscall) {
-		/* Restart the system call - no handlers present */
-		if (regs->gr[28] == -ERESTART_RESTARTBLOCK) {
-			unsigned int *usp = (unsigned int *)regs->gr[30];
-
-			/* Setup a trampoline to restart the syscall
-			 * with __NR_restart_syscall
-			 *
-			 *  0: <return address (orig r31)>
-			 *  4: <2nd half for 64-bit>
-			 *  8: ldw 0(%sp), %r31
-			 * 12: be 0x100(%sr2, %r0)
-			 * 16: ldi __NR_restart_syscall, %r20
-			 */
-#ifndef __LP64__
-			put_user(regs->gr[31], &usp[0]);
-			put_user(0x0fc0109f, &usp[2]);
-#else
-			put_user(regs->gr[31] >> 32, &usp[0]);
-			put_user(regs->gr[31] & 0xffffffff, &usp[1]);
-			put_user(0x0fc010df, &usp[2]);
-#endif
-			put_user(0xe0008200, &usp[3]);
-			put_user(0x34140000, &usp[4]);
-
-			/* Stack is 64-byte aligned, and we only need
-			 * to flush 1 cache line.
-			 * Flushing one cacheline is cheap.
-			 * "sync" on bigger (> 4 way) boxes is not.
-			 */
-			asm("fdc %%r0(%%sr3, %0)\n"
-			    "sync\n"
-			    "fic %%r0(%%sr3, %0)\n"
-			    "sync\n"
-			    : : "r"(regs->gr[30]));
-
-			regs->gr[31] = regs->gr[30] + 8;
-			/* Preserve original r28. */
-			regs->gr[28] = regs->orig_r28;
-		} else if (regs->gr[28] == -ERESTARTNOHAND ||
-		           regs->gr[28] == -ERESTARTSYS ||
-		           regs->gr[28] == -ERESTARTNOINTR) {
-			/* Hooray for delayed branching.  We don't
-                           have to restore %r20 (the system call
-                           number) because it gets loaded in the delay
-                           slot of the branch external instruction. */
-			regs->gr[31] -= 8;
-			/* Preserve original r28. */
-			regs->gr[28] = regs->orig_r28;
-		}
-	}
+	if (in_syscall)
+		insert_restart_trampoline(regs);
 	
 	DBG(1,"do_signal: Exit (not delivered), regs->gr[28] = %ld\n", 
 		regs->gr[28]);