Merge branch irq/remove-handle-domain-irq-20211026 into irq/irqchip-next

* irq/remove-handle-domain-irq-20211026:
  : Large rework of the architecture entry code from Mark Rutland.
  : From the cover letter:
  :
  : <quote>
  : The handle_domain_{irq,nmi}() functions were oringally intended as a
  : convenience, but recent rework to entry code across the kernel tree has
  : demonstrated that they cause more pain than they're worth and prevent
  : architectures from being able to write robust entry code.
  :
  : This series reworks the irq code to remove them, handling the necessary
  : entry work consistently in entry code (be it architectural or generic).
  : </quote>
  MIPS: irq: Avoid an unused-variable error
  irq: remove handle_domain_{irq,nmi}()
  irq: remove CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY
  irq: riscv: perform irqentry in entry code
  irq: openrisc: perform irqentry in entry code
  irq: csky: perform irqentry in entry code
  irq: arm64: perform irqentry in entry code
  irq: arm: perform irqentry in entry code
  irq: add a (temporary) CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY
  irq: nds32: avoid CONFIG_HANDLE_DOMAIN_IRQ
  irq: arc: avoid CONFIG_HANDLE_DOMAIN_IRQ
  irq: add generic_handle_arch_irq()
  irq: unexport handle_irq_desc()
  irq: simplify handle_domain_{irq,nmi}()
  irq: mips: simplify do_domain_IRQ()
  irq: mips: stop (ab)using handle_domain_irq()
  irq: mips: simplify bcm6345_l1_irq_handle()
  irq: mips: avoid nested irq_enter()

Signed-off-by: Marc Zyngier <maz@kernel.org>

24 files changed, 63 insertions, 75 deletions

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 3a5a80f302e1..b4ae6058902a 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -40,7 +40,6 @@ config ARC
 	select HAVE_KRETPROBES
 	select HAVE_MOD_ARCH_SPECIFIC
 	select HAVE_PERF_EVENTS
-	select HANDLE_DOMAIN_IRQ
 	select IRQ_DOMAIN
 	select MODULES_USE_ELF_RELA
 	select OF
diff --git a/arch/arc/kernel/irq.c b/arch/arc/kernel/irq.c
index ef909dd4b40c..dd09b58ff82d 100644
--- a/arch/arc/kernel/irq.c
+++ b/arch/arc/kernel/irq.c
@@ -6,6 +6,8 @@
 #include <linux/interrupt.h>
 #include <linux/irqchip.h>
 #include <asm/mach_desc.h>
+
+#include <asm/irq_regs.h>
 #include <asm/smp.h>
 
 /*
@@ -39,5 +41,11 @@ void __init init_IRQ(void)
  */
 void arch_do_IRQ(unsigned int hwirq, struct pt_regs *regs)
 {
-	handle_domain_irq(NULL, hwirq, regs);
+	struct pt_regs *old_regs;
+
+	irq_enter();
+	old_regs = set_irq_regs(regs);
+	generic_handle_domain_irq(NULL, hwirq);
+	set_irq_regs(old_regs);
+	irq_exit();
 }
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index fc196421b2ce..3361a6c29ee9 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -64,7 +64,6 @@ config ARM
 	select GENERIC_PCI_IOMAP
 	select GENERIC_SCHED_CLOCK
 	select GENERIC_SMP_IDLE_THREAD
-	select HANDLE_DOMAIN_IRQ
 	select HARDIRQS_SW_RESEND
 	select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
 	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
diff --git a/arch/arm/kernel/entry-armv.S b/arch/arm/kernel/entry-armv.S
index 241b73d64df7..3d0b6169ab86 100644
--- a/arch/arm/kernel/entry-armv.S
+++ b/arch/arm/kernel/entry-armv.S
@@ -38,14 +38,11 @@
  */
 	.macro	irq_handler
 #ifdef CONFIG_GENERIC_IRQ_MULTI_HANDLER
-	ldr	r1, =handle_arch_irq
 	mov	r0, sp
-	badr	lr, 9997f
-	ldr	pc, [r1]
+	bl	generic_handle_arch_irq
 #else
 	arch_irq_handler_default
 #endif
-9997:
 	.endm
 
 	.macro	pabt_helper
diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c
index 20ab1e607522..b79975bd988c 100644
--- a/arch/arm/kernel/irq.c
+++ b/arch/arm/kernel/irq.c
@@ -63,11 +63,8 @@ int arch_show_interrupts(struct seq_file *p, int prec)
  */
 void handle_IRQ(unsigned int irq, struct pt_regs *regs)
 {
-	struct pt_regs *old_regs = set_irq_regs(regs);
 	struct irq_desc *desc;
 
-	irq_enter();
-
 	/*
 	 * Some hardware gives randomly wrong interrupts.  Rather
 	 * than crashing, do something sensible.
@@ -81,9 +78,6 @@ void handle_IRQ(unsigned int irq, struct pt_regs *regs)
 		handle_irq_desc(desc);
 	else
 		ack_bad_irq(irq);
-
-	irq_exit();
-	set_irq_regs(old_regs);
 }
 
 /*
@@ -92,7 +86,15 @@ void handle_IRQ(unsigned int irq, struct pt_regs *regs)
 asmlinkage void __exception_irq_entry
 asm_do_IRQ(unsigned int irq, struct pt_regs *regs)
 {
+	struct pt_regs *old_regs;
+
+	irq_enter();
+	old_regs = set_irq_regs(regs);
+
 	handle_IRQ(irq, regs);
+
+	set_irq_regs(old_regs);
+	irq_exit();
 }
 
 void __init init_IRQ(void)
diff --git a/arch/arm/mach-imx/avic.c b/arch/arm/mach-imx/avic.c
index 21bce4049cec..cf6546ddc7a3 100644
--- a/arch/arm/mach-imx/avic.c
+++ b/arch/arm/mach-imx/avic.c
@@ -154,7 +154,7 @@ static void __exception_irq_entry avic_handle_irq(struct pt_regs *regs)
 		if (nivector == 0xffff)
 			break;
 
-		handle_domain_irq(domain, nivector, regs);
+		generic_handle_domain_irq(domain, nivector);
 	} while (1);
 }
 
diff --git a/arch/arm/mach-imx/tzic.c b/arch/arm/mach-imx/tzic.c
index 479a01bdac56..8b3d98d288d9 100644
--- a/arch/arm/mach-imx/tzic.c
+++ b/arch/arm/mach-imx/tzic.c
@@ -134,7 +134,7 @@ static void __exception_irq_entry tzic_handle_irq(struct pt_regs *regs)
 			while (stat) {
 				handled = 1;
 				irqofs = fls(stat) - 1;
-				handle_domain_irq(domain, irqofs + i * 32, regs);
+				generic_handle_domain_irq(domain, irqofs + i * 32);
 				stat &= ~(1 << irqofs);
 			}
 		}
diff --git a/arch/arm/mach-omap1/irq.c b/arch/arm/mach-omap1/irq.c
index b11edc8a46f0..ee6a93083154 100644
--- a/arch/arm/mach-omap1/irq.c
+++ b/arch/arm/mach-omap1/irq.c
@@ -165,7 +165,7 @@ asmlinkage void __exception_irq_entry omap1_handle_irq(struct pt_regs *regs)
 		}
 irq:
 		if (irqnr)
-			handle_domain_irq(domain, irqnr, regs);
+			generic_handle_domain_irq(domain, irqnr);
 		else
 			break;
 	} while (irqnr);
diff --git a/arch/arm/mach-s3c/irq-s3c24xx.c b/arch/arm/mach-s3c/irq-s3c24xx.c
index 3edc5f614eef..45dfd546e6fa 100644
--- a/arch/arm/mach-s3c/irq-s3c24xx.c
+++ b/arch/arm/mach-s3c/irq-s3c24xx.c
@@ -354,7 +354,7 @@ static inline int s3c24xx_handle_intc(struct s3c_irq_intc *intc,
 	if (!(pnd & (1 << offset)))
 		offset =  __ffs(pnd);
 
-	handle_domain_irq(intc->domain, intc_offset + offset, regs);
+	generic_handle_domain_irq(intc->domain, intc_offset + offset);
 	return true;
 }
 
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 5c7ae4c3954b..e6593a03ea27 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -133,7 +133,6 @@ config ARM64
 	select GENERIC_TIME_VSYSCALL
 	select GENERIC_GETTIMEOFDAY
 	select GENERIC_VDSO_TIME_NS
-	select HANDLE_DOMAIN_IRQ
 	select HARDIRQS_SW_RESEND
 	select HAVE_MOVE_PMD
 	select HAVE_MOVE_PUD
diff --git a/arch/arm64/kernel/entry-common.c b/arch/arm64/kernel/entry-common.c
index 32f9796c4ffe..f7408edf8571 100644
--- a/arch/arm64/kernel/entry-common.c
+++ b/arch/arm64/kernel/entry-common.c
@@ -17,6 +17,7 @@
 #include <asm/daifflags.h>
 #include <asm/esr.h>
 #include <asm/exception.h>
+#include <asm/irq_regs.h>
 #include <asm/kprobes.h>
 #include <asm/mmu.h>
 #include <asm/processor.h>
@@ -219,22 +220,6 @@ static void noinstr arm64_exit_el1_dbg(struct pt_regs *regs)
 		lockdep_hardirqs_on(CALLER_ADDR0);
 }
 
-static void noinstr enter_el1_irq_or_nmi(struct pt_regs *regs)
-{
-	if (IS_ENABLED(CONFIG_ARM64_PSEUDO_NMI) && !interrupts_enabled(regs))
-		arm64_enter_nmi(regs);
-	else
-		enter_from_kernel_mode(regs);
-}
-
-static void noinstr exit_el1_irq_or_nmi(struct pt_regs *regs)
-{
-	if (IS_ENABLED(CONFIG_ARM64_PSEUDO_NMI) && !interrupts_enabled(regs))
-		arm64_exit_nmi(regs);
-	else
-		exit_to_kernel_mode(regs);
-}
-
 static void __sched arm64_preempt_schedule_irq(void)
 {
 	lockdep_assert_irqs_disabled();
@@ -263,10 +248,14 @@ static void __sched arm64_preempt_schedule_irq(void)
 static void do_interrupt_handler(struct pt_regs *regs,
 				 void (*handler)(struct pt_regs *))
 {
+	struct pt_regs *old_regs = set_irq_regs(regs);
+
 	if (on_thread_stack())
 		call_on_irq_stack(regs, handler);
 	else
 		handler(regs);
+
+	set_irq_regs(old_regs);
 }
 
 extern void (*handle_arch_irq)(struct pt_regs *);
@@ -432,13 +421,22 @@ asmlinkage void noinstr el1h_64_sync_handler(struct pt_regs *regs)
 	}
 }
 
-static void noinstr el1_interrupt(struct pt_regs *regs,
-				  void (*handler)(struct pt_regs *))
+static __always_inline void __el1_pnmi(struct pt_regs *regs,
+				       void (*handler)(struct pt_regs *))
 {
-	write_sysreg(DAIF_PROCCTX_NOIRQ, daif);
+	arm64_enter_nmi(regs);
+	do_interrupt_handler(regs, handler);
+	arm64_exit_nmi(regs);
+}
+
+static __always_inline void __el1_irq(struct pt_regs *regs,
+				      void (*handler)(struct pt_regs *))
+{
+	enter_from_kernel_mode(regs);
 
-	enter_el1_irq_or_nmi(regs);
+	irq_enter_rcu();
 	do_interrupt_handler(regs, handler);
+	irq_exit_rcu();
 
 	/*
 	 * Note: thread_info::preempt_count includes both thread_info::count
@@ -449,7 +447,17 @@ static void noinstr el1_interrupt(struct pt_regs *regs,
 	    READ_ONCE(current_thread_info()->preempt_count) == 0)
 		arm64_preempt_schedule_irq();
 
-	exit_el1_irq_or_nmi(regs);
+	exit_to_kernel_mode(regs);
+}
+static void noinstr el1_interrupt(struct pt_regs *regs,
+				  void (*handler)(struct pt_regs *))
+{
+	write_sysreg(DAIF_PROCCTX_NOIRQ, daif);
+
+	if (IS_ENABLED(CONFIG_ARM64_PSEUDO_NMI) && !interrupts_enabled(regs))
+		__el1_pnmi(regs, handler);
+	else
+		__el1_irq(regs, handler);
 }
 
 asmlinkage void noinstr el1h_64_irq_handler(struct pt_regs *regs)
@@ -667,7 +675,9 @@ static void noinstr el0_interrupt(struct pt_regs *regs,
 	if (regs->pc & BIT(55))
 		arm64_apply_bp_hardening();
 
+	irq_enter_rcu();
 	do_interrupt_handler(regs, handler);
+	irq_exit_rcu();
 
 	exit_to_user_mode(regs);
 }
diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
index 9d4d898df76b..e0bd71b9e23f 100644
--- a/arch/csky/Kconfig
+++ b/arch/csky/Kconfig
@@ -17,7 +17,6 @@ config CSKY
 	select CSKY_APB_INTC
 	select DMA_DIRECT_REMAP
 	select IRQ_DOMAIN
-	select HANDLE_DOMAIN_IRQ
 	select DW_APB_TIMER_OF
 	select GENERIC_IOREMAP
 	select GENERIC_LIB_ASHLDI3
diff --git a/arch/csky/kernel/entry.S b/arch/csky/kernel/entry.S
index 00e3c8ebf9b8..a4ababf25e24 100644
--- a/arch/csky/kernel/entry.S
+++ b/arch/csky/kernel/entry.S
@@ -249,7 +249,7 @@ ENTRY(csky_irq)
 
 
 	mov	a0, sp
-	jbsr	csky_do_IRQ
+	jbsr	generic_handle_arch_irq
 
 	jmpi	ret_from_exception
 
diff --git a/arch/csky/kernel/irq.c b/arch/csky/kernel/irq.c
index 03a1930f1cbb..fcdaf3156286 100644
--- a/arch/csky/kernel/irq.c
+++ b/arch/csky/kernel/irq.c
@@ -15,8 +15,3 @@ void __init init_IRQ(void)
 	setup_smp_ipi();
 #endif
 }
-
-asmlinkage void __irq_entry csky_do_IRQ(struct pt_regs *regs)
-{
-	handle_arch_irq(regs);
-}
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 2c03b27cec02..bf172aeaa2c0 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -47,7 +47,6 @@ config MIPS
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_TIME_VSYSCALL
 	select GUP_GET_PTE_LOW_HIGH if CPU_MIPS32 && PHYS_ADDR_T_64BIT
-	select HANDLE_DOMAIN_IRQ
 	select HAVE_ARCH_COMPILER_H
 	select HAVE_ARCH_JUMP_LABEL
 	select HAVE_ARCH_KGDB if MIPS_FP_SUPPORT
diff --git a/arch/mips/cavium-octeon/octeon-irq.c b/arch/mips/cavium-octeon/octeon-irq.c
index be5d4afcd30f..844f882096e6 100644
--- a/arch/mips/cavium-octeon/octeon-irq.c
+++ b/arch/mips/cavium-octeon/octeon-irq.c
@@ -2609,7 +2609,10 @@ static void octeon_irq_ciu3_ip2(void)
 		else
 			hw = intsn;
 
-		ret = handle_domain_irq(domain, hw, NULL);
+		irq_enter();
+		ret = generic_handle_domain_irq(domain, hw);
+		irq_exit();
+
 		if (ret < 0) {
 			union cvmx_ciu3_iscx_w1c isc_w1c;
 			u64 isc_w1c_addr = ciu3_addr + CIU3_ISC_W1C(intsn);
diff --git a/arch/mips/kernel/irq.c b/arch/mips/kernel/irq.c
index d20e002b3246..5e11582fe308 100644
--- a/arch/mips/kernel/irq.c
+++ b/arch/mips/kernel/irq.c
@@ -111,15 +111,9 @@ void __irq_entry do_IRQ(unsigned int irq)
 #ifdef CONFIG_IRQ_DOMAIN
 void __irq_entry do_domain_IRQ(struct irq_domain *domain, unsigned int hwirq)
 {
-	struct irq_desc *desc;
-
 	irq_enter();
 	check_stack_overflow();
-
-	desc = irq_resolve_mapping(domain, hwirq);
-	if (likely(desc))
-		handle_irq_desc(desc);
-
+	generic_handle_domain_irq(domain, hwirq);
 	irq_exit();
 }
 #endif
diff --git a/arch/nds32/Kconfig b/arch/nds32/Kconfig
index aea26e739543..4d1421b18734 100644
--- a/arch/nds32/Kconfig
+++ b/arch/nds32/Kconfig
@@ -27,7 +27,6 @@ config NDS32
 	select GENERIC_LIB_MULDI3
 	select GENERIC_LIB_UCMPDI2
 	select GENERIC_TIME_VSYSCALL
-	select HANDLE_DOMAIN_IRQ
 	select HAVE_ARCH_TRACEHOOK
 	select HAVE_DEBUG_KMEMLEAK
 	select HAVE_EXIT_THREAD
diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
index e804026b4797..c2491b295d60 100644
--- a/arch/openrisc/Kconfig
+++ b/arch/openrisc/Kconfig
@@ -13,7 +13,6 @@ config OPENRISC
 	select OF
 	select OF_EARLY_FLATTREE
 	select IRQ_DOMAIN
-	select HANDLE_DOMAIN_IRQ
 	select GPIOLIB
 	select HAVE_ARCH_TRACEHOOK
 	select SPARSE_IRQ
diff --git a/arch/openrisc/kernel/entry.S b/arch/openrisc/kernel/entry.S
index edaa775a648e..59c6d3aa7081 100644
--- a/arch/openrisc/kernel/entry.S
+++ b/arch/openrisc/kernel/entry.S
@@ -569,8 +569,8 @@ EXCEPTION_ENTRY(_external_irq_handler)
 #endif
 	CLEAR_LWA_FLAG(r3)
 	l.addi	r3,r1,0
-	l.movhi	r8,hi(do_IRQ)
-	l.ori	r8,r8,lo(do_IRQ)
+	l.movhi	r8,hi(generic_handle_arch_irq)
+	l.ori	r8,r8,lo(generic_handle_arch_irq)
 	l.jalr r8
 	l.nop
 	l.j    _ret_from_intr
diff --git a/arch/openrisc/kernel/irq.c b/arch/openrisc/kernel/irq.c
index c38fa863afa8..f38e10962a84 100644
--- a/arch/openrisc/kernel/irq.c
+++ b/arch/openrisc/kernel/irq.c
@@ -36,8 +36,3 @@ void __init init_IRQ(void)
 {
 	irqchip_init();
 }
-
-void __irq_entry do_IRQ(struct pt_regs *regs)
-{
-	handle_arch_irq(regs);
-}
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 301a54233c7e..353e28f5f849 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -62,7 +62,6 @@ config RISCV
 	select GENERIC_SCHED_CLOCK
 	select GENERIC_SMP_IDLE_THREAD
 	select GENERIC_TIME_VSYSCALL if MMU && 64BIT
-	select HANDLE_DOMAIN_IRQ
 	select HAVE_ARCH_AUDITSYSCALL
 	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
 	select HAVE_ARCH_JUMP_LABEL_RELATIVE if !XIP_KERNEL
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
index 98f502654edd..64236f7efde5 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -130,8 +130,7 @@ skip_context_tracking:
 
 	/* Handle interrupts */
 	move a0, sp /* pt_regs */
-	la a1, handle_arch_irq
-	REG_L a1, (a1)
+	la a1, generic_handle_arch_irq
 	jr a1
 1:
 	/*
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 921d9d7df400..2f6da845c9ae 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -140,12 +140,9 @@ void arch_irq_work_raise(void)
 
 void handle_IPI(struct pt_regs *regs)
 {
-	struct pt_regs *old_regs = set_irq_regs(regs);
 	unsigned long *pending_ipis = &ipi_data[smp_processor_id()].bits;
 	unsigned long *stats = ipi_data[smp_processor_id()].stats;
 
-	irq_enter();
-
 	riscv_clear_ipi();
 
 	while (true) {
@@ -156,7 +153,7 @@ void handle_IPI(struct pt_regs *regs)
 
 		ops = xchg(pending_ipis, 0);
 		if (ops == 0)
-			goto done;
+			return;
 
 		if (ops & (1 << IPI_RESCHEDULE)) {
 			stats[IPI_RESCHEDULE]++;
@@ -189,10 +186,6 @@ void handle_IPI(struct pt_regs *regs)
 		/* Order data access and bit testing. */
 		mb();
 	}
-
-done:
-	irq_exit();
-	set_irq_regs(old_regs);
 }
 
 static const char * const ipi_names[] = {