LoongArch: KVM: Use standard bitops API with eiointc

[ Upstream commit d23bd87 ]

Standard bitops APIs such test_bit() is used here, rather than manually
calculating the offset and mask. Also use non-atomic API __set_bit() and
__clear_bit() rather than set_bit() and clear_bit(), since the global
spinlock is held already.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Stable-dep-of: 0dfd9ea ("LoongArch: KVM: Use kvm_get_vcpu_by_id() instead of kvm_get_vcpu()")
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: bibo-mao

arch/loongarch/kvm/intc/eiointc.c

@@ -9,7 +9,7 @@
 
 static void eiointc_set_sw_coreisr(struct loongarch_eiointc *s)
 {
-	int ipnum, cpu, cpuid, irq_index, irq_mask, irq;
+	int ipnum, cpu, cpuid, irq;
 	struct kvm_vcpu *vcpu;
 
 	for (irq = 0; irq < EIOINTC_IRQS; irq++) {
@@ -18,25 +18,23 @@ static void eiointc_set_sw_coreisr(struct loongarch_eiointc *s)
 			ipnum = count_trailing_zeros(ipnum);
 			ipnum = (ipnum >= 0 && ipnum < 4) ? ipnum : 0;
 		}
-		irq_index = irq / 32;
-		irq_mask = BIT(irq & 0x1f);
 
 		cpuid = s->coremap.reg_u8[irq];
 		vcpu = kvm_get_vcpu_by_cpuid(s->kvm, cpuid);
 		if (!vcpu)
 			continue;
 
 		cpu = vcpu->vcpu_id;
-		if (!!(s->coreisr.reg_u32[cpu][irq_index] & irq_mask))
-			set_bit(irq, s->sw_coreisr[cpu][ipnum]);
+		if (test_bit(irq, (unsigned long *)s->coreisr.reg_u32[cpu]))
+			__set_bit(irq, s->sw_coreisr[cpu][ipnum]);
 		else
-			clear_bit(irq, s->sw_coreisr[cpu][ipnum]);
+			__clear_bit(irq, s->sw_coreisr[cpu][ipnum]);
 	}
 }
 
 static void eiointc_update_irq(struct loongarch_eiointc *s, int irq, int level)
 {
-	int ipnum, cpu, found, irq_index, irq_mask;
+	int ipnum, cpu, found;
 	struct kvm_vcpu *vcpu;
 	struct kvm_interrupt vcpu_irq;
 
@@ -48,19 +46,16 @@ static void eiointc_update_irq(struct loongarch_eiointc *s, int irq, int level)
 
 	cpu = s->sw_coremap[irq];
 	vcpu = kvm_get_vcpu(s->kvm, cpu);
-	irq_index = irq / 32;
-	irq_mask = BIT(irq & 0x1f);
-
 	if (level) {
 		/* if not enable return false */
-		if (((s->enable.reg_u32[irq_index]) & irq_mask) == 0)
+		if (!test_bit(irq, (unsigned long *)s->enable.reg_u32))
 			return;
-		s->coreisr.reg_u32[cpu][irq_index] |= irq_mask;
+		__set_bit(irq, (unsigned long *)s->coreisr.reg_u32[cpu]);
 		found = find_first_bit(s->sw_coreisr[cpu][ipnum], EIOINTC_IRQS);
-		set_bit(irq, s->sw_coreisr[cpu][ipnum]);
+		__set_bit(irq, s->sw_coreisr[cpu][ipnum]);
 	} else {
-		s->coreisr.reg_u32[cpu][irq_index] &= ~irq_mask;
-		clear_bit(irq, s->sw_coreisr[cpu][ipnum]);
+		__clear_bit(irq, (unsigned long *)s->coreisr.reg_u32[cpu]);
+		__clear_bit(irq, s->sw_coreisr[cpu][ipnum]);
 		found = find_first_bit(s->sw_coreisr[cpu][ipnum], EIOINTC_IRQS);
 	}
 
@@ -110,8 +105,8 @@ void eiointc_set_irq(struct loongarch_eiointc *s, int irq, int level)
 	unsigned long flags;
 	unsigned long *isr = (unsigned long *)s->isr.reg_u8;
 
-	level ? set_bit(irq, isr) : clear_bit(irq, isr);
 	spin_lock_irqsave(&s->lock, flags);
+	level ? __set_bit(irq, isr) : __clear_bit(irq, isr);
 	eiointc_update_irq(s, irq, level);
 	spin_unlock_irqrestore(&s->lock, flags);
 }