[RFC PATCH 17/36] arm64: remove daifflags.h

[Vladimir Murzin <vladimir.murzin@arm.com>]

From: Ada Couprie Diaz <ada.coupriediaz@arm.com>

Interrupt masking is now split in different APIs and `local_daif_...`
functions are not in use anymore.
The `DAIF_...` masks defines are now in `asm/interrupts/common_flags.h`,
so we can safely remove `daifflags.h` and all `#include`s referring to it.

Only kprobes.c and process.c use `DAIF_...` masks defines, so add the
new header there.

Signed-off-by: Ada Couprie Diaz <ada.coupriediaz@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
---
 arch/arm64/include/asm/daifflags.h    | 123 --------------------------
 arch/arm64/include/asm/entry-common.h |   1 -
 arch/arm64/include/asm/kvm_host.h     |   1 -
 arch/arm64/include/asm/mmu_context.h  |   1 -
 arch/arm64/kernel/debug-monitors.c    |   1 -
 arch/arm64/kernel/probes/kprobes.c    |   2 +-
 arch/arm64/kernel/signal.c            |   1 -
 arch/arm64/kernel/traps.c             |   1 -
 arch/arm64/mm/fault.c                 |   1 -
 9 files changed, 1 insertion(+), 131 deletions(-)
 delete mode 100644 arch/arm64/include/asm/daifflags.h

diff --git a/arch/arm64/include/asm/daifflags.h b/arch/arm64/include/asm/daifflags.h
deleted file mode 100644
index 8f097a2d9099..000000000000
--- a/arch/arm64/include/asm/daifflags.h
+++ /dev/null
@@ -1,123 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2017 ARM Ltd.
- */
-#ifndef __ASM_DAIFFLAGS_H
-#define __ASM_DAIFFLAGS_H
-
-#include <linux/irqflags.h>
-
-#include <asm/arch_gicv3.h>
-#include <asm/barrier.h>
-#include <asm/cpufeature.h>
-#include <asm/ptrace.h>
-
-#define DAIF_PROCCTX		0
-#define DAIF_PROCCTX_NOIRQ	(PSR_I_BIT | PSR_F_BIT)
-#define DAIF_ERRCTX		(PSR_A_BIT | PSR_I_BIT | PSR_F_BIT)
-#define DAIF_MASK		(PSR_D_BIT | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT)
-
-
-/* mask/save/unmask/restore all exceptions, including interrupts. */
-static __always_inline void local_daif_mask(void)
-{
-	WARN_ON(system_has_prio_mask_debugging() &&
-		(read_sysreg_s(SYS_ICC_PMR_EL1) == (GIC_PRIO_IRQOFF |
-						    GIC_PRIO_PSR_I_SET)));
-
-	asm volatile(
-		"msr	daifset, #0xf		// local_daif_mask\n"
-		:
-		:
-		: "memory");
-
-	/* Don't really care for a dsb here, we don't intend to enable IRQs */
-	if (system_uses_irq_prio_masking())
-		gic_write_pmr(GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET);
-
-	trace_hardirqs_off();
-}
-
-static __always_inline unsigned long local_daif_save_flags(void)
-{
-	unsigned long flags;
-
-	flags = read_sysreg(daif);
-
-	if (system_uses_irq_prio_masking()) {
-		/* If IRQs are masked with PMR, reflect it in the flags */
-		if (read_sysreg_s(SYS_ICC_PMR_EL1) != GIC_PRIO_IRQON)
-			flags |= PSR_I_BIT | PSR_F_BIT;
-	}
-
-	return flags;
-}
-
-static __always_inline unsigned long local_daif_save(void)
-{
-	unsigned long flags;
-
-	flags = local_daif_save_flags();
-
-	local_daif_mask();
-
-	return flags;
-}
-
-static __always_inline void local_daif_restore(unsigned long flags)
-{
-	bool irq_disabled = flags & PSR_I_BIT;
-
-	WARN_ON(system_has_prio_mask_debugging() &&
-		(read_sysreg(daif) & (PSR_I_BIT | PSR_F_BIT)) != (PSR_I_BIT | PSR_F_BIT));
-
-	if (!irq_disabled) {
-		trace_hardirqs_on();
-
-		if (system_uses_irq_prio_masking()) {
-			gic_write_pmr(GIC_PRIO_IRQON);
-			pmr_sync();
-		}
-	} else if (system_uses_irq_prio_masking()) {
-		u64 pmr;
-
-		if (!(flags & PSR_A_BIT)) {
-			/*
-			 * If interrupts are disabled but we can take
-			 * asynchronous errors, we can take NMIs
-			 */
-			flags &= ~(PSR_I_BIT | PSR_F_BIT);
-			pmr = GIC_PRIO_IRQOFF;
-		} else {
-			pmr = GIC_PRIO_IRQON | GIC_PRIO_PSR_I_SET;
-		}
-
-		/*
-		 * There has been concern that the write to daif
-		 * might be reordered before this write to PMR.
-		 * From the ARM ARM DDI 0487D.a, section D1.7.1
-		 * "Accessing PSTATE fields":
-		 *   Writes to the PSTATE fields have side-effects on
-		 *   various aspects of the PE operation. All of these
-		 *   side-effects are guaranteed:
-		 *     - Not to be visible to earlier instructions in
-		 *       the execution stream.
-		 *     - To be visible to later instructions in the
-		 *       execution stream
-		 *
-		 * Also, writes to PMR are self-synchronizing, so no
-		 * interrupts with a lower priority than PMR is signaled
-		 * to the PE after the write.
-		 *
-		 * So we don't need additional synchronization here.
-		 */
-		gic_write_pmr(pmr);
-	}
-
-	write_sysreg(flags, daif);
-
-	if (irq_disabled)
-		trace_hardirqs_off();
-}
-
-#endif
diff --git a/arch/arm64/include/asm/entry-common.h b/arch/arm64/include/asm/entry-common.h
index 1905765159aa..73d82a8d8e95 100644
--- a/arch/arm64/include/asm/entry-common.h
+++ b/arch/arm64/include/asm/entry-common.h
@@ -6,7 +6,6 @@
 #include <linux/thread_info.h>
 
 #include <asm/cpufeature.h>
-#include <asm/daifflags.h>
 #include <asm/fpsimd.h>
 #include <asm/mte.h>
 #include <asm/stacktrace.h>
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index bae2c4f92ef5..74358e93f1bb 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -23,7 +23,6 @@
 #include <asm/barrier.h>
 #include <asm/cpufeature.h>
 #include <asm/cputype.h>
-#include <asm/daifflags.h>
 #include <asm/fpsimd.h>
 #include <asm/kvm.h>
 #include <asm/kvm_asm.h>
diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/mmu_context.h
index 803b68758152..b3354a1350cf 100644
--- a/arch/arm64/include/asm/mmu_context.h
+++ b/arch/arm64/include/asm/mmu_context.h
@@ -19,7 +19,6 @@
 
 #include <asm/cacheflush.h>
 #include <asm/cpufeature.h>
-#include <asm/daifflags.h>
 #include <asm/gcs.h>
 #include <asm/proc-fns.h>
 #include <asm/cputype.h>
diff --git a/arch/arm64/kernel/debug-monitors.c b/arch/arm64/kernel/debug-monitors.c
index e271fbac5f82..5db27c7e86bb 100644
--- a/arch/arm64/kernel/debug-monitors.c
+++ b/arch/arm64/kernel/debug-monitors.c
@@ -19,7 +19,6 @@
 
 #include <asm/cpufeature.h>
 #include <asm/cputype.h>
-#include <asm/daifflags.h>
 #include <asm/debug-monitors.h>
 #include <asm/exception.h>
 #include <asm/kgdb.h>
diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c
index 43a0361a8bf0..d9d25d184309 100644
--- a/arch/arm64/kernel/probes/kprobes.c
+++ b/arch/arm64/kernel/probes/kprobes.c
@@ -24,9 +24,9 @@
 #include <linux/vmalloc.h>
 
 #include <asm/cacheflush.h>
-#include <asm/daifflags.h>
 #include <asm/debug-monitors.h>
 #include <asm/insn.h>
+#include <asm/interrupts/common_flags.h>
 #include <asm/irq.h>
 #include <asm/text-patching.h>
 #include <asm/ptrace.h>
diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c
index 38e6fa204c17..2276d316cc9e 100644
--- a/arch/arm64/kernel/signal.c
+++ b/arch/arm64/kernel/signal.c
@@ -22,7 +22,6 @@
 #include <linux/syscalls.h>
 #include <linux/pkeys.h>
 
-#include <asm/daifflags.h>
 #include <asm/debug-monitors.h>
 #include <asm/elf.h>
 #include <asm/exception.h>
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index 914282016069..77b6be6fc4c1 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -33,7 +33,6 @@
 #include <asm/atomic.h>
 #include <asm/bug.h>
 #include <asm/cpufeature.h>
-#include <asm/daifflags.h>
 #include <asm/debug-monitors.h>
 #include <asm/efi.h>
 #include <asm/esr.h>
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 85e23388f9bb..83aca64745f0 100644
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -34,7 +34,6 @@
 #include <asm/cpufeature.h>
 #include <asm/efi.h>
 #include <asm/exception.h>
-#include <asm/daifflags.h>
 #include <asm/debug-monitors.h>
 #include <asm/esr.h>
 #include <asm/kprobes.h>
-- 
2.34.1