genirq: Add and use an irq_data_update_affinity helper

Some architectures and irqchip drivers modify the cpumask returned by
irq_data_get_affinity_mask, usually by copying in to it. This is
problematic for uniprocessor configurations, where the affinity mask
should be constant, as it is known at compile time.

Add and use a setter for the affinity mask, following the pattern of
irq_data_update_effective_affinity. This allows the getter function to
return a const cpumask pointer.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> # Xen bits
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220701200056.46555-7-samuel@sholland.org

5 files changed, 7 insertions, 7 deletions

diff --git a/arch/alpha/kernel/irq.c b/arch/alpha/kernel/irq.c
index f6d2946edbd2..15f2effd6baf 100644
--- a/arch/alpha/kernel/irq.c
+++ b/arch/alpha/kernel/irq.c
@@ -60,7 +60,7 @@ int irq_select_affinity(unsigned int irq)
 		cpu = (cpu < (NR_CPUS-1) ? cpu + 1 : 0);
 	last_cpu = cpu;
 
-	cpumask_copy(irq_data_get_affinity_mask(data), cpumask_of(cpu));
+	irq_data_update_affinity(data, cpumask_of(cpu));
 	chip->irq_set_affinity(data, cpumask_of(cpu), false);
 	return 0;
 }
diff --git a/arch/ia64/kernel/iosapic.c b/arch/ia64/kernel/iosapic.c
index 35adcf89035a..99300850abc1 100644
--- a/arch/ia64/kernel/iosapic.c
+++ b/arch/ia64/kernel/iosapic.c
@@ -834,7 +834,7 @@ iosapic_unregister_intr (unsigned int gsi)
 	if (iosapic_intr_info[irq].count == 0) {
 #ifdef CONFIG_SMP
 		/* Clear affinity */
-		cpumask_setall(irq_get_affinity_mask(irq));
+		irq_data_update_affinity(irq_get_irq_data(irq), cpu_all_mask);
 #endif
 		/* Clear the interrupt information */
 		iosapic_intr_info[irq].dest = 0;
diff --git a/arch/ia64/kernel/irq.c b/arch/ia64/kernel/irq.c
index ecef17c7c35b..275b9ea58c64 100644
--- a/arch/ia64/kernel/irq.c
+++ b/arch/ia64/kernel/irq.c
@@ -57,8 +57,8 @@ static char irq_redir [NR_IRQS]; // = { [0 ... NR_IRQS-1] = 1 };
 void set_irq_affinity_info (unsigned int irq, int hwid, int redir)
 {
 	if (irq < NR_IRQS) {
-		cpumask_copy(irq_get_affinity_mask(irq),
-			     cpumask_of(cpu_logical_id(hwid)));
+		irq_data_update_affinity(irq_get_irq_data(irq),
+					 cpumask_of(cpu_logical_id(hwid)));
 		irq_redir[irq] = (char) (redir & 0xff);
 	}
 }
diff --git a/arch/ia64/kernel/msi_ia64.c b/arch/ia64/kernel/msi_ia64.c
index df5c28f252e3..025e5133c860 100644
--- a/arch/ia64/kernel/msi_ia64.c
+++ b/arch/ia64/kernel/msi_ia64.c
@@ -37,7 +37,7 @@ static int ia64_set_msi_irq_affinity(struct irq_data *idata,
 	msg.data = data;
 
 	pci_write_msi_msg(irq, &msg);
-	cpumask_copy(irq_data_get_affinity_mask(idata), cpumask_of(cpu));
+	irq_data_update_affinity(idata, cpumask_of(cpu));
 
 	return 0;
 }
@@ -132,7 +132,7 @@ static int dmar_msi_set_affinity(struct irq_data *data,
 	msg.address_lo |= MSI_ADDR_DEST_ID_CPU(cpu_physical_id(cpu));
 
 	dmar_msi_write(irq, &msg);
-	cpumask_copy(irq_data_get_affinity_mask(data), mask);
+	irq_data_update_affinity(data, mask);
 
 	return 0;
 }
diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c
index 0fe2d79fb123..5ebb1771b4ab 100644
--- a/arch/parisc/kernel/irq.c
+++ b/arch/parisc/kernel/irq.c
@@ -315,7 +315,7 @@ unsigned long txn_affinity_addr(unsigned int irq, int cpu)
 {
 #ifdef CONFIG_SMP
 	struct irq_data *d = irq_get_irq_data(irq);
-	cpumask_copy(irq_data_get_affinity_mask(d), cpumask_of(cpu));
+	irq_data_update_affinity(d, cpumask_of(cpu));
 #endif
 
 	return per_cpu(cpu_data, cpu).txn_addr;