2 files changed, 154 insertions, 163 deletions

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 52fa56399a50..a2fd72e0ab35 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -1437,27 +1437,21 @@ void enable_x2apic(void)
 
 int __init enable_IR(void)
 {
-#ifdef CONFIG_INTR_REMAP
+#ifdef CONFIG_IRQ_REMAP
 	if (!intr_remapping_supported()) {
 		pr_debug("intr-remapping not supported\n");
-		return 0;
+		return -1;
 	}
 
 	if (!x2apic_preenabled && skip_ioapic_setup) {
 		pr_info("Skipped enabling intr-remap because of skipping "
 			"io-apic setup\n");
-		return 0;
+		return -1;
 	}
 
-	if (enable_intr_remapping(x2apic_supported()))
-		return 0;
-
-	pr_info("Enabled Interrupt-remapping\n");
-
-	return 1;
-
+	return enable_intr_remapping();
 #endif
-	return 0;
+	return -1;
 }
 
 void __init enable_IR_x2apic(void)
@@ -1481,11 +1475,11 @@ void __init enable_IR_x2apic(void)
 	mask_ioapic_entries();
 
 	if (dmar_table_init_ret)
-		ret = 0;
+		ret = -1;
 	else
 		ret = enable_IR();
 
-	if (!ret) {
+	if (ret < 0) {
 		/* IR is required if there is APIC ID > 255 even when running
 		 * under KVM
 		 */
@@ -1499,6 +1493,9 @@ void __init enable_IR_x2apic(void)
 		x2apic_force_phys();
 	}
 
+	if (ret == IRQ_REMAP_XAPIC_MODE)
+		goto nox2apic;
+
 	x2apic_enabled = 1;
 
 	if (x2apic_supported() && !x2apic_mode) {
@@ -1508,19 +1505,21 @@ void __init enable_IR_x2apic(void)
 	}
 
 nox2apic:
-	if (!ret) /* IR enabling failed */
+	if (ret < 0) /* IR enabling failed */
 		restore_ioapic_entries();
 	legacy_pic->restore_mask();
 	local_irq_restore(flags);
 
 out:
-	if (x2apic_enabled)
+	if (x2apic_enabled || !x2apic_supported())
 		return;
 
 	if (x2apic_preenabled)
 		panic("x2apic: enabled by BIOS but kernel init failed.");
-	else if (cpu_has_x2apic)
-		pr_info("Not enabling x2apic, Intr-remapping init failed.\n");
+	else if (ret == IRQ_REMAP_XAPIC_MODE)
+		pr_info("x2apic not enabled, IRQ remapping is in xapic mode\n");
+	else if (ret < 0)
+		pr_info("x2apic not enabled, IRQ remapping init failed\n");
 }
 
 #ifdef CONFIG_X86_64
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 8eb863e27ea6..229e19f3eb57 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -394,13 +394,21 @@ union entry_union {
 	struct IO_APIC_route_entry entry;
 };
 
+static struct IO_APIC_route_entry __ioapic_read_entry(int apic, int pin)
+{
+	union entry_union eu;
+
+	eu.w1 = io_apic_read(apic, 0x10 + 2 * pin);
+	eu.w2 = io_apic_read(apic, 0x11 + 2 * pin);
+	return eu.entry;
+}
+
 static struct IO_APIC_route_entry ioapic_read_entry(int apic, int pin)
 {
 	union entry_union eu;
 	unsigned long flags;
 	raw_spin_lock_irqsave(&ioapic_lock, flags);
-	eu.w1 = io_apic_read(apic, 0x10 + 2 * pin);
-	eu.w2 = io_apic_read(apic, 0x11 + 2 * pin);
+	eu.entry = __ioapic_read_entry(apic, pin);
 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 	return eu.entry;
 }
@@ -529,18 +537,6 @@ static void io_apic_modify_irq(struct irq_cfg *cfg,
 		__io_apic_modify_irq(entry, mask_and, mask_or, final);
 }
 
-static void __mask_and_edge_IO_APIC_irq(struct irq_pin_list *entry)
-{
-	__io_apic_modify_irq(entry, ~IO_APIC_REDIR_LEVEL_TRIGGER,
-			     IO_APIC_REDIR_MASKED, NULL);
-}
-
-static void __unmask_and_level_IO_APIC_irq(struct irq_pin_list *entry)
-{
-	__io_apic_modify_irq(entry, ~IO_APIC_REDIR_MASKED,
-			     IO_APIC_REDIR_LEVEL_TRIGGER, NULL);
-}
-
 static void io_apic_sync(struct irq_pin_list *entry)
 {
 	/*
@@ -585,6 +581,66 @@ static void unmask_ioapic_irq(struct irq_data *data)
 	unmask_ioapic(data->chip_data);
 }
 
+/*
+ * IO-APIC versions below 0x20 don't support EOI register.
+ * For the record, here is the information about various versions:
+ *     0Xh     82489DX
+ *     1Xh     I/OAPIC or I/O(x)APIC which are not PCI 2.2 Compliant
+ *     2Xh     I/O(x)APIC which is PCI 2.2 Compliant
+ *     30h-FFh Reserved
+ *
+ * Some of the Intel ICH Specs (ICH2 to ICH5) documents the io-apic
+ * version as 0x2. This is an error with documentation and these ICH chips
+ * use io-apic's of version 0x20.
+ *
+ * For IO-APIC's with EOI register, we use that to do an explicit EOI.
+ * Otherwise, we simulate the EOI message manually by changing the trigger
+ * mode to edge and then back to level, with RTE being masked during this.
+ */
+static void __eoi_ioapic_pin(int apic, int pin, int vector, struct irq_cfg *cfg)
+{
+	if (mpc_ioapic_ver(apic) >= 0x20) {
+		/*
+		 * Intr-remapping uses pin number as the virtual vector
+		 * in the RTE. Actual vector is programmed in
+		 * intr-remapping table entry. Hence for the io-apic
+		 * EOI we use the pin number.
+		 */
+		if (cfg && irq_remapped(cfg))
+			io_apic_eoi(apic, pin);
+		else
+			io_apic_eoi(apic, vector);
+	} else {
+		struct IO_APIC_route_entry entry, entry1;
+
+		entry = entry1 = __ioapic_read_entry(apic, pin);
+
+		/*
+		 * Mask the entry and change the trigger mode to edge.
+		 */
+		entry1.mask = 1;
+		entry1.trigger = IOAPIC_EDGE;
+
+		__ioapic_write_entry(apic, pin, entry1);
+
+		/*
+		 * Restore the previous level triggered entry.
+		 */
+		__ioapic_write_entry(apic, pin, entry);
+	}
+}
+
+static void eoi_ioapic_irq(unsigned int irq, struct irq_cfg *cfg)
+{
+	struct irq_pin_list *entry;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&ioapic_lock, flags);
+	for_each_irq_pin(entry, cfg->irq_2_pin)
+		__eoi_ioapic_pin(entry->apic, entry->pin, cfg->vector, cfg);
+	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+}
+
 static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
 {
 	struct IO_APIC_route_entry entry;
@@ -593,10 +649,44 @@ static void clear_IO_APIC_pin(unsigned int apic, unsigned int pin)
 	entry = ioapic_read_entry(apic, pin);
 	if (entry.delivery_mode == dest_SMI)
 		return;
+
+	/*
+	 * Make sure the entry is masked and re-read the contents to check
+	 * if it is a level triggered pin and if the remote-IRR is set.
+	 */
+	if (!entry.mask) {
+		entry.mask = 1;
+		ioapic_write_entry(apic, pin, entry);
+		entry = ioapic_read_entry(apic, pin);
+	}
+
+	if (entry.irr) {
+		unsigned long flags;
+
+		/*
+		 * Make sure the trigger mode is set to level. Explicit EOI
+		 * doesn't clear the remote-IRR if the trigger mode is not
+		 * set to level.
+		 */
+		if (!entry.trigger) {
+			entry.trigger = IOAPIC_LEVEL;
+			ioapic_write_entry(apic, pin, entry);
+		}
+
+		raw_spin_lock_irqsave(&ioapic_lock, flags);
+		__eoi_ioapic_pin(apic, pin, entry.vector, NULL);
+		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
+	}
+
 	/*
-	 * Disable it in the IO-APIC irq-routing table:
+	 * Clear the rest of the bits in the IO-APIC RTE except for the mask
+	 * bit.
 	 */
 	ioapic_mask_entry(apic, pin);
+	entry = ioapic_read_entry(apic, pin);
+	if (entry.irr)
+		printk(KERN_ERR "Unable to reset IRR for apic: %d, pin :%d\n",
+		       mpc_ioapic_id(apic), pin);
 }
 
 static void clear_IO_APIC (void)
@@ -1202,7 +1292,6 @@ void __setup_vector_irq(int cpu)
 }
 
 static struct irq_chip ioapic_chip;
-static struct irq_chip ir_ioapic_chip;
 
 #ifdef CONFIG_X86_32
 static inline int IO_APIC_irq_trigger(int irq)
@@ -1246,7 +1335,7 @@ static void ioapic_register_intr(unsigned int irq, struct irq_cfg *cfg,
 
 	if (irq_remapped(cfg)) {
 		irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
-		chip = &ir_ioapic_chip;
+		irq_remap_modify_chip_defaults(chip);
 		fasteoi = trigger != 0;
 	}
 
@@ -2255,7 +2344,7 @@ ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
 	return ret;
 }
 
-#ifdef CONFIG_INTR_REMAP
+#ifdef CONFIG_IRQ_REMAP
 
 /*
  * Migrate the IO-APIC irq in the presence of intr-remapping.
@@ -2267,6 +2356,9 @@ ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
  * updated vector information), by using a virtual vector (io-apic pin number).
  * Real vector that is used for interrupting cpu will be coming from
  * the interrupt-remapping table entry.
+ *
+ * As the migration is a simple atomic update of IRTE, the same mechanism
+ * is used to migrate MSI irq's in the presence of interrupt-remapping.
  */
 static int
 ir_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
@@ -2291,10 +2383,16 @@ ir_ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
 	irte.dest_id = IRTE_DEST(dest);
 
 	/*
-	 * Modified the IRTE and flushes the Interrupt entry cache.
+	 * Atomically updates the IRTE with the new destination, vector
+	 * and flushes the interrupt entry cache.
 	 */
 	modify_irte(irq, &irte);
 
+	/*
+	 * After this point, all the interrupts will start arriving
+	 * at the new destination. So, time to cleanup the previous
+	 * vector allocation.
+	 */
 	if (cfg->move_in_progress)
 		send_cleanup_vector(cfg);
 
@@ -2407,48 +2505,6 @@ static void ack_apic_edge(struct irq_data *data)
 
 atomic_t irq_mis_count;
 
-/*
- * IO-APIC versions below 0x20 don't support EOI register.
- * For the record, here is the information about various versions:
- *     0Xh     82489DX
- *     1Xh     I/OAPIC or I/O(x)APIC which are not PCI 2.2 Compliant
- *     2Xh     I/O(x)APIC which is PCI 2.2 Compliant
- *     30h-FFh Reserved
- *
- * Some of the Intel ICH Specs (ICH2 to ICH5) documents the io-apic
- * version as 0x2. This is an error with documentation and these ICH chips
- * use io-apic's of version 0x20.
- *
- * For IO-APIC's with EOI register, we use that to do an explicit EOI.
- * Otherwise, we simulate the EOI message manually by changing the trigger
- * mode to edge and then back to level, with RTE being masked during this.
-*/
-static void eoi_ioapic_irq(unsigned int irq, struct irq_cfg *cfg)
-{
-	struct irq_pin_list *entry;
-	unsigned long flags;
-
-	raw_spin_lock_irqsave(&ioapic_lock, flags);
-	for_each_irq_pin(entry, cfg->irq_2_pin) {
-		if (mpc_ioapic_ver(entry->apic) >= 0x20) {
-			/*
-			 * Intr-remapping uses pin number as the virtual vector
-			 * in the RTE. Actual vector is programmed in
-			 * intr-remapping table entry. Hence for the io-apic
-			 * EOI we use the pin number.
-			 */
-			if (irq_remapped(cfg))
-				io_apic_eoi(entry->apic, entry->pin);
-			else
-				io_apic_eoi(entry->apic, cfg->vector);
-		} else {
-			__mask_and_edge_IO_APIC_irq(entry);
-			__unmask_and_level_IO_APIC_irq(entry);
-		}
-	}
-	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
-}
-
 static void ack_apic_level(struct irq_data *data)
 {
 	struct irq_cfg *cfg = data->chip_data;
@@ -2552,7 +2608,7 @@ static void ack_apic_level(struct irq_data *data)
 	}
 }
 
-#ifdef CONFIG_INTR_REMAP
+#ifdef CONFIG_IRQ_REMAP
 static void ir_ack_apic_edge(struct irq_data *data)
 {
 	ack_APIC_irq();
@@ -2563,7 +2619,23 @@ static void ir_ack_apic_level(struct irq_data *data)
 	ack_APIC_irq();
 	eoi_ioapic_irq(data->irq, data->chip_data);
 }
-#endif /* CONFIG_INTR_REMAP */
+
+static void ir_print_prefix(struct irq_data *data, struct seq_file *p)
+{
+	seq_printf(p, " IR-%s", data->chip->name);
+}
+
+static void irq_remap_modify_chip_defaults(struct irq_chip *chip)
+{
+	chip->irq_print_chip = ir_print_prefix;
+	chip->irq_ack = ir_ack_apic_edge;
+	chip->irq_eoi = ir_ack_apic_level;
+
+#ifdef CONFIG_SMP
+	chip->irq_set_affinity = ir_ioapic_set_affinity;
+#endif
+}
+#endif /* CONFIG_IRQ_REMAP */
 
 static struct irq_chip ioapic_chip __read_mostly = {
 	.name			= "IO-APIC",
@@ -2578,21 +2650,6 @@ static struct irq_chip ioapic_chip __read_mostly = {
 	.irq_retrigger		= ioapic_retrigger_irq,
 };
 
-static struct irq_chip ir_ioapic_chip __read_mostly = {
-	.name			= "IR-IO-APIC",
-	.irq_startup		= startup_ioapic_irq,
-	.irq_mask		= mask_ioapic_irq,
-	.irq_unmask		= unmask_ioapic_irq,
-#ifdef CONFIG_INTR_REMAP
-	.irq_ack		= ir_ack_apic_edge,
-	.irq_eoi		= ir_ack_apic_level,
-#ifdef CONFIG_SMP
-	.irq_set_affinity	= ir_ioapic_set_affinity,
-#endif
-#endif
-	.irq_retrigger		= ioapic_retrigger_irq,
-};
-
 static inline void init_IO_APIC_traps(void)
 {
 	struct irq_cfg *cfg;
@@ -3144,45 +3201,6 @@ msi_set_affinity(struct irq_data *data, const struct cpumask *mask, bool force)
 
 	return 0;
 }
-#ifdef CONFIG_INTR_REMAP
-/*
- * Migrate the MSI irq to another cpumask. This migration is
- * done in the process context using interrupt-remapping hardware.
- */
-static int
-ir_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
-		    bool force)
-{
-	struct irq_cfg *cfg = data->chip_data;
-	unsigned int dest, irq = data->irq;
-	struct irte irte;
-
-	if (get_irte(irq, &irte))
-		return -1;
-
-	if (__ioapic_set_affinity(data, mask, &dest))
-		return -1;
-
-	irte.vector = cfg->vector;
-	irte.dest_id = IRTE_DEST(dest);
-
-	/*
-	 * atomically update the IRTE with the new destination and vector.
-	 */
-	modify_irte(irq, &irte);
-
-	/*
-	 * After this point, all the interrupts will start arriving
-	 * at the new destination. So, time to cleanup the previous
-	 * vector allocation.
-	 */
-	if (cfg->move_in_progress)
-		send_cleanup_vector(cfg);
-
-	return 0;
-}
-
-#endif
 #endif /* CONFIG_SMP */
 
 /*
@@ -3200,19 +3218,6 @@ static struct irq_chip msi_chip = {
 	.irq_retrigger		= ioapic_retrigger_irq,
 };
 
-static struct irq_chip msi_ir_chip = {
-	.name			= "IR-PCI-MSI",
-	.irq_unmask		= unmask_msi_irq,
-	.irq_mask		= mask_msi_irq,
-#ifdef CONFIG_INTR_REMAP
-	.irq_ack		= ir_ack_apic_edge,
-#ifdef CONFIG_SMP
-	.irq_set_affinity	= ir_msi_set_affinity,
-#endif
-#endif
-	.irq_retrigger		= ioapic_retrigger_irq,
-};
-
 /*
  * Map the PCI dev to the corresponding remapping hardware unit
  * and allocate 'nvec' consecutive interrupt-remapping table entries
@@ -3255,7 +3260,7 @@ static int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int irq)
 
 	if (irq_remapped(irq_get_chip_data(irq))) {
 		irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
-		chip = &msi_ir_chip;
+		irq_remap_modify_chip_defaults(chip);
 	}
 
 	irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "edge");
@@ -3328,7 +3333,7 @@ void native_teardown_msi_irq(unsigned int irq)
 	destroy_irq(irq);
 }
 
-#if defined (CONFIG_DMAR) || defined (CONFIG_INTR_REMAP)
+#ifdef CONFIG_DMAR_TABLE
 #ifdef CONFIG_SMP
 static int
 dmar_msi_set_affinity(struct irq_data *data, const struct cpumask *mask,
@@ -3409,19 +3414,6 @@ static int hpet_msi_set_affinity(struct irq_data *data,
 
 #endif /* CONFIG_SMP */
 
-static struct irq_chip ir_hpet_msi_type = {
-	.name			= "IR-HPET_MSI",
-	.irq_unmask		= hpet_msi_unmask,
-	.irq_mask		= hpet_msi_mask,
-#ifdef CONFIG_INTR_REMAP
-	.irq_ack		= ir_ack_apic_edge,
-#ifdef CONFIG_SMP
-	.irq_set_affinity	= ir_msi_set_affinity,
-#endif
-#endif
-	.irq_retrigger		= ioapic_retrigger_irq,
-};
-
 static struct irq_chip hpet_msi_type = {
 	.name = "HPET_MSI",
 	.irq_unmask = hpet_msi_unmask,
@@ -3458,7 +3450,7 @@ int arch_setup_hpet_msi(unsigned int irq, unsigned int id)
 	hpet_msi_write(irq_get_handler_data(irq), &msg);
 	irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
 	if (irq_remapped(irq_get_chip_data(irq)))
-		chip = &ir_hpet_msi_type;
+		irq_remap_modify_chip_defaults(chip);
 
 	irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "edge");
 	return 0;