Introduce acpi_ioapic_registered() to check whether an IOAPIC has already been registered, it will be used when enabling IOAPIC hotplug. Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx> --- Hi Thomas, I have fixed docbook issues in this patch. Regards! Gerry --- arch/x86/include/asm/io_apic.h | 1 + arch/x86/kernel/acpi/boot.c | 22 ++++++++++++++++++++++ arch/x86/kernel/apic/io_apic.c | 11 +++++++++++ include/linux/acpi.h | 1 + 4 files changed, 35 insertions(+) diff --git a/arch/x86/include/asm/io_apic.h b/arch/x86/include/asm/io_apic.h index 7c04b8ec22a4..ca742d5249db 100644 --- a/arch/x86/include/asm/io_apic.h +++ b/arch/x86/include/asm/io_apic.h @@ -191,6 +191,7 @@ extern void mp_unmap_irq(int irq); extern int mp_register_ioapic(int id, u32 address, u32 gsi_base, struct ioapic_domain_cfg *cfg); extern int mp_unregister_ioapic(u32 gsi_base); +extern int mp_ioapic_registered(u32 gsi_base); extern int mp_irqdomain_map(struct irq_domain *domain, unsigned int virq, irq_hw_number_t hwirq); extern void mp_irqdomain_unmap(struct irq_domain *domain, unsigned int virq); diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c index 0e67d792741d..5a69df5dba56 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -821,6 +821,28 @@ int acpi_unregister_ioapic(acpi_handle handle, u32 gsi_base) } EXPORT_SYMBOL(acpi_unregister_ioapic); +/** + * acpi_ioapic_registered - Check whether IOAPIC assoicatied with @gsi_base + * has been registered + * @handle: ACPI handle of the IOAPIC deivce + * @gsi_base: GSI base associated with the IOAPIC + * + * Assume caller holds some type of lock to serialize acpi_ioapic_registered() + * with acpi_register_ioapic()/acpi_unregister_ioapic(). + */ +int acpi_ioapic_registered(acpi_handle handle, u32 gsi_base) +{ + int ret = 0; + +#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC + down_read(&acpi_ioapic_rwsem); + ret = mp_ioapic_registered(gsi_base); + up_read(&acpi_ioapic_rwsem); +#endif + + return ret; +} + static int __init acpi_parse_sbf(struct acpi_table_header *table) { struct acpi_table_boot *sb; diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 7fec2a8f72f3..eba25bccefd2 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -4013,6 +4013,17 @@ int mp_unregister_ioapic(u32 gsi_base) return 0; } +int mp_ioapic_registered(u32 gsi_base) +{ + int ioapic; + + for_each_ioapic(ioapic) + if (ioapics[ioapic].gsi_config.gsi_base == gsi_base) + return 1; + + return 0; +} + int mp_irqdomain_map(struct irq_domain *domain, unsigned int virq, irq_hw_number_t hwirq) { diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 3574f137242e..e916cc9ca5a8 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -152,6 +152,7 @@ int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr); int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base); int acpi_unregister_ioapic(acpi_handle handle, u32 gsi_base); +int acpi_ioapic_registered(acpi_handle handle, u32 gsi_base); void acpi_irq_stats_init(void); extern u32 acpi_irq_handled; extern u32 acpi_irq_not_handled; -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html