[PATCH v3 1/5] powerpc/interrupt: Rename and lightly change syscall_exit_prepare_main()

@@ -243,11 +243,10 @@ static notrace void booke_load_dbcr0(void)
 #endif
 }
 
-notrace unsigned long syscall_exit_prepare_main(unsigned long r3,
-						struct pt_regs *regs)
+static notrace unsigned long
+interrupt_exit_user_prepare_main(struct pt_regs *regs, unsigned long ret)
 {
 	unsigned long ti_flags;
-	unsigned long ret = 0;
 
 again:
 	ti_flags = READ_ONCE(current_thread_info()->flags);

@@ -269,7 +268,7 @@ notrace unsigned long syscall_exit_prepare_main(unsigned long r3,
 		ti_flags = READ_ONCE(current_thread_info()->flags);
 	}
 
-	if (IS_ENABLED(CONFIG_PPC_BOOK3S) && IS_ENABLED(CONFIG_PPC_FPU)) {
+	if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && IS_ENABLED(CONFIG_PPC_FPU)) {
 		if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) &&
 				unlikely((ti_flags & _TIF_RESTORE_TM))) {
 			restore_tm_state(regs);

@@ -365,7 +364,7 @@ notrace unsigned long syscall_exit_prepare(unsigned long r3,
 	}
 
 	local_irq_disable();
-	ret |= syscall_exit_prepare_main(r3, regs);
+	ret = interrupt_exit_user_prepare_main(regs, ret);
 
 #ifdef CONFIG_PPC64
 	regs->exit_result = ret;

@@ -393,7 +392,7 @@ notrace unsigned long syscall_exit_restart(unsigned long r3, struct pt_regs *reg
 
 	BUG_ON(!user_mode(regs));
 
-	regs->exit_result |= syscall_exit_prepare_main(r3, regs);
+	regs->exit_result = interrupt_exit_user_prepare_main(regs, regs->exit_result);
 
 	return regs->exit_result;
 }

@@ -400,9 +400,7 @@ notrace unsigned long syscall_exit_restart(unsigned long r3, struct pt_regs *reg
 
 notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs)
 {
-	unsigned long ti_flags;
-	unsigned long flags;
-	unsigned long ret = 0;
+	unsigned long ret;
 
 	if (!IS_ENABLED(CONFIG_BOOKE) && !IS_ENABLED(CONFIG_40x))
 		BUG_ON(!(regs->msr & MSR_RI));

@@ -416,63 +414,14 @@ notrace unsigned long interrupt_exit_user_prepare(struct pt_regs *regs)
 	 */
 	kuap_assert_locked();
 
-	local_irq_save(flags);
-
-again:
-	ti_flags = READ_ONCE(current_thread_info()->flags);
-	while (unlikely(ti_flags & (_TIF_USER_WORK_MASK & ~_TIF_RESTORE_TM))) {
-		local_irq_enable(); /* returning to user: may enable */
-		if (ti_flags & _TIF_NEED_RESCHED) {
-			schedule();
-		} else {
-			if (ti_flags & _TIF_SIGPENDING)
-				ret |= _TIF_RESTOREALL;
-			do_notify_resume(regs, ti_flags);
-		}
-		local_irq_disable();
-		ti_flags = READ_ONCE(current_thread_info()->flags);
-	}
-
-	if (IS_ENABLED(CONFIG_PPC_BOOK3S_64) && IS_ENABLED(CONFIG_PPC_FPU)) {
-		if (IS_ENABLED(CONFIG_PPC_TRANSACTIONAL_MEM) &&
-				unlikely((ti_flags & _TIF_RESTORE_TM))) {
-			restore_tm_state(regs);
-		} else {
-			unsigned long mathflags = MSR_FP;
-
-			if (cpu_has_feature(CPU_FTR_VSX))
-				mathflags |= MSR_VEC | MSR_VSX;
-			else if (cpu_has_feature(CPU_FTR_ALTIVEC))
-				mathflags |= MSR_VEC;
-
-			/* See above restore_math comment */
-			if ((regs->msr & mathflags) != mathflags)
-				restore_math(regs);
-		}
-	}
-
-	if (!prep_irq_for_user_exit()) {
-		local_irq_enable();
-		local_irq_disable();
-		goto again;
-	}
-
-	booke_load_dbcr0();
-
-#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
-	local_paca->tm_scratch = regs->msr;
-#endif
+	local_irq_disable();
 
-	account_cpu_user_exit();
+	ret = interrupt_exit_user_prepare_main(regs, 0);
 
 #ifdef CONFIG_PPC64
 	regs->exit_result = ret;
 #endif
 
-	/* Restore user access locks last */
-	kuap_user_restore(regs);
-	kuep_unlock();
-
 	return ret;
 }
 

@@ -46,27 +46,28 @@ static inline bool exit_must_hard_disable(void)
  * This should be called with local irqs disabled, but if they were previously
  * enabled when the interrupt handler returns (indicating a process-context /
  * synchronous interrupt) then irqs_enabled should be true.
+ *
+ * restartable is true then EE/RI can be left on because interrupts are handled
+ * with a restart sequence.
  */
-static notrace __always_inline bool prep_irq_for_user_exit(void)
+static notrace __always_inline bool prep_irq_for_kernel_enabled_exit(bool restartable)
 {
-	user_enter_irqoff();
 	/* This must be done with RI=1 because tracing may touch vmaps */
 	trace_hardirqs_on();
 
 #ifdef CONFIG_PPC32
 	__hard_EE_RI_disable();
 #else
-	if (exit_must_hard_disable())
+	if (exit_must_hard_disable() || !restartable)
 		__hard_EE_RI_disable();
 
 	/* This pattern matches prep_irq_for_idle */
 	if (unlikely(lazy_irq_pending_nocheck())) {
-		if (exit_must_hard_disable()) {
+		if (exit_must_hard_disable() || !restartable) {
 			local_paca->irq_happened |= PACA_IRQ_HARD_DIS;
 			__hard_RI_enable();
 		}
 		trace_hardirqs_off();
-		user_exit_irqoff();
 
 		return false;
 	}

@@ -74,28 +75,26 @@ static notrace __always_inline bool prep_irq_for_user_exit(void)
 	return true;
 }
 
-/*
- * restartable is true then EE/RI can be left on because interrupts are handled
- * with a restart sequence.
- */
-static notrace __always_inline bool prep_irq_for_kernel_enabled_exit(bool restartable)
+static notrace __always_inline bool prep_irq_for_user_exit(void)
 {
+	user_enter_irqoff();
 	/* This must be done with RI=1 because tracing may touch vmaps */
 	trace_hardirqs_on();
 
 #ifdef CONFIG_PPC32
 	__hard_EE_RI_disable();
 #else
-	if (exit_must_hard_disable() || !restartable)
+	if (exit_must_hard_disable())
 		__hard_EE_RI_disable();
 
 	/* This pattern matches prep_irq_for_idle */
 	if (unlikely(lazy_irq_pending_nocheck())) {
-		if (exit_must_hard_disable() || !restartable) {
+		if (exit_must_hard_disable()) {
 			local_paca->irq_happened |= PACA_IRQ_HARD_DIS;
 			__hard_RI_enable();
 		}
 		trace_hardirqs_off();
+		user_exit_irqoff();
 
 		return false;
 	}

@@ -50,7 +50,7 @@ static inline bool exit_must_hard_disable(void)
  * restartable is true then EE/RI can be left on because interrupts are handled
  * with a restart sequence.
  */
-static notrace __always_inline bool prep_irq_for_kernel_enabled_exit(bool restartable)
+static notrace __always_inline bool prep_irq_for_enabled_exit(bool restartable)
 {
 	/* This must be done with RI=1 because tracing may touch vmaps */
 	trace_hardirqs_on();

@@ -77,29 +77,14 @@ static notrace __always_inline bool prep_irq_for_kernel_enabled_exit(bool restar
 
 static notrace __always_inline bool prep_irq_for_user_exit(void)
 {
-	user_enter_irqoff();
-	/* This must be done with RI=1 because tracing may touch vmaps */
-	trace_hardirqs_on();
-
-#ifdef CONFIG_PPC32
-	__hard_EE_RI_disable();
-#else
-	if (exit_must_hard_disable())
-		__hard_EE_RI_disable();
+	bool ret;
 
-	/* This pattern matches prep_irq_for_idle */
-	if (unlikely(lazy_irq_pending_nocheck())) {
-		if (exit_must_hard_disable()) {
-			local_paca->irq_happened |= PACA_IRQ_HARD_DIS;
-			__hard_RI_enable();
-		}
-		trace_hardirqs_off();
+	user_enter_irqoff();
+	ret = prep_irq_for_enabled_exit(true);
+	if (!ret)
 		user_exit_irqoff();
 
-		return false;
-	}
-#endif
-	return true;
+	return ret;
 }
 
 /* Has to run notrace because it is entered not completely "reconciled" */

@@ -465,7 +450,7 @@ notrace unsigned long interrupt_exit_kernel_prepare(struct pt_regs *regs)
 		 * Stack store exit can't be restarted because the interrupt
 		 * stack frame might have been clobbered.
 		 */
-		if (!prep_irq_for_kernel_enabled_exit(unlikely(stack_store))) {
+		if (!prep_irq_for_enabled_exit(unlikely(stack_store))) {
 			/*
 			 * Replay pending soft-masked interrupts now. Don't
 			 * just local_irq_enabe(); local_irq_disable(); because

@@ -75,18 +75,6 @@ static notrace __always_inline bool prep_irq_for_enabled_exit(bool restartable)
 	return true;
 }
 
-static notrace __always_inline bool prep_irq_for_user_exit(void)
-{
-	bool ret;
-
-	user_enter_irqoff();
-	ret = prep_irq_for_enabled_exit(true);
-	if (!ret)
-		user_exit_irqoff();
-
-	return ret;
-}
-
 /* Has to run notrace because it is entered not completely "reconciled" */
 notrace long system_call_exception(long r3, long r4, long r5,
 				   long r6, long r7, long r8,

@@ -276,7 +264,9 @@ interrupt_exit_user_prepare_main(struct pt_regs *regs, unsigned long ret)
 		}
 	}
 
-	if (!prep_irq_for_user_exit()) {
+	user_enter_irqoff();
+	if (!prep_irq_for_enabled_exit(true)) {
+		user_exit_irqoff();
 		local_irq_enable();
 		local_irq_disable();
 		goto again;