[Patch v8 17/18] x86, irq: Introduce helper to check whether an IOAPIC has been registered
flat view
STALE4312d
REVIEWED: 1 (0M)
From: Jiang Liu <hidden>
Date: 2014-11-02 06:03:52
Also in:
linux-acpi, linux-pci, lkml
Subsystem:
acpi, the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
"Rafael J. Wysocki", Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
1 review trailer.
Introduce acpi_ioapic_registered() to check whether an IOAPIC has already been registered, it will be used when enabling IOAPIC hotplug. Acked-by: Pavel Machek <redacted> Signed-off-by: Jiang Liu <redacted> --- 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 37a990146e90..0e18705cee1e 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c@@ -825,6 +825,28 @@ 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 9e5432ee2070..df3858de3031 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c@@ -4018,6 +4018,17 @@ 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 77cecd0350e7..be6be0f91337 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;
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1.7.10.4