Merge tag 'ioapic-cleanups-for-tip' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu into x86/apic

Pull "x86 IOAPIC code from interrupt remapping details cleanups" from
Joerg Roedel:

"These patches move all interrupt remapping specific checks out of the
x86 core code and replaces the respective call-sites with function
pointers. As a result the interrupt remapping code is better abstraced
from x86 core interrupt handling code.

The code was rebased to v3.8-rc4 and tested on systems with AMD-Vi and
Intel VT-d (both capable of interrupt remapping). The systems were
tested with IOMMU enabled and with IOMMU disabled. No issues were found."

Signed-off-by: Ingo Molnar <[e-mail]>

arch/x86/include/asm/hpet.h

···
 extern void hpet_msi_read(struct hpet_dev *hdev, struct msi_msg *msg);
 
 #ifdef CONFIG_PCI_MSI
-extern int arch_setup_hpet_msi(unsigned int irq, unsigned int id);
+extern int default_setup_hpet_msi(unsigned int irq, unsigned int id);
 #else
-static inline int arch_setup_hpet_msi(unsigned int irq, unsigned int id)
+static inline int default_setup_hpet_msi(unsigned int irq, unsigned int id)
 {
 	return -EINVAL;
 }
···
 static inline int hpet_enable(void) { return 0; }
 static inline int is_hpet_enabled(void) { return 0; }
 #define hpet_readl(a) 0
+#define default_setup_hpet_msi	NULL
 
 #endif
 #endif /* _ASM_X86_HPET_H */

arch/x86/include/asm/hw_irq.h

···
 	irq_attr->polarity	= polarity;
 }
 
+/* Intel specific interrupt remapping information */
 struct irq_2_iommu {
 	struct intel_iommu *iommu;
 	u16 irte_index;
 	u16 sub_handle;
 	u8  irte_mask;
+};
+
+/* AMD specific interrupt remapping information */
+struct irq_2_irte {
+	u16 devid; /* Device ID for IRTE table */
+	u16 index; /* Index into IRTE table*/
 };
 
 /*
···
 	u8			vector;
 	u8			move_in_progress : 1;
 #ifdef CONFIG_IRQ_REMAP
-	struct irq_2_iommu	irq_2_iommu;
+	u8			remapped : 1;
+	union {
+		struct irq_2_iommu irq_2_iommu;
+		struct irq_2_irte  irq_2_irte;
+	};
 #endif
 };
 

arch/x86/include/asm/io_apic.h

···
 	(mp_irq_entries && !skip_ioapic_setup && io_apic_irqs)
 
 struct io_apic_irq_attr;
+struct irq_cfg;
 extern int io_apic_set_pci_routing(struct device *dev, int irq,
 		 struct io_apic_irq_attr *irq_attr);
 void setup_IO_APIC_irq_extra(u32 gsi);
 extern void ioapic_insert_resources(void);
 
+extern int native_setup_ioapic_entry(int, struct IO_APIC_route_entry *,
+				     unsigned int, int,
+				     struct io_apic_irq_attr *);
+extern int native_setup_ioapic_entry(int, struct IO_APIC_route_entry *,
+				     unsigned int, int,
+				     struct io_apic_irq_attr *);
+extern void eoi_ioapic_irq(unsigned int irq, struct irq_cfg *cfg);
+
+extern void native_compose_msi_msg(struct pci_dev *pdev,
+				   unsigned int irq, unsigned int dest,
+				   struct msi_msg *msg, u8 hpet_id);
+extern void native_eoi_ioapic_pin(int apic, int pin, int vector);
 int io_apic_setup_irq_pin_once(unsigned int irq, int node, struct io_apic_irq_attr *attr);
 
 extern int save_ioapic_entries(void);
···
 extern unsigned int native_io_apic_read(unsigned int apic, unsigned int reg);
 extern void native_io_apic_write(unsigned int apic, unsigned int reg, unsigned int val);
 extern void native_io_apic_modify(unsigned int apic, unsigned int reg, unsigned int val);
+extern void native_disable_io_apic(void);
+extern void native_io_apic_print_entries(unsigned int apic, unsigned int nr_entries);
+extern void intel_ir_io_apic_print_entries(unsigned int apic, unsigned int nr_entries);
+extern int native_ioapic_set_affinity(struct irq_data *,
+				      const struct cpumask *,
+				      bool);
 
 static inline unsigned int io_apic_read(unsigned int apic, unsigned int reg)
 {
···
 {
 	x86_io_apic_ops.modify(apic, reg, value);
 }
+
+extern void io_apic_eoi(unsigned int apic, unsigned int vector);
+
 #else  /* !CONFIG_X86_IO_APIC */
 
 #define io_apic_assign_pci_irqs 0
···
 #define native_io_apic_read		NULL
 #define native_io_apic_write		NULL
 #define native_io_apic_modify		NULL
+#define native_disable_io_apic		NULL
+#define native_io_apic_print_entries	NULL
+#define native_ioapic_set_affinity	NULL
+#define native_setup_ioapic_entry	NULL
+#define native_compose_msi_msg		NULL
+#define native_eoi_ioapic_pin		NULL
 #endif
 
 #endif /* _ASM_X86_IO_APIC_H */

arch/x86/include/asm/irq_remapping.h

···
 
 #ifdef CONFIG_IRQ_REMAP
 
-extern int irq_remapping_enabled;
-
 extern void setup_irq_remapping_ops(void);
 extern int irq_remapping_supported(void);
 extern int irq_remapping_prepare(void);
···
 				       unsigned int destination,
 				       int vector,
 				       struct io_apic_irq_attr *attr);
-extern int set_remapped_irq_affinity(struct irq_data *data,
-				     const struct cpumask *mask,
-				     bool force);
 extern void free_remapped_irq(int irq);
 extern void compose_remapped_msi_msg(struct pci_dev *pdev,
 				     unsigned int irq, unsigned int dest,
 				     struct msi_msg *msg, u8 hpet_id);
-extern int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec);
-extern int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
-				  int index, int sub_handle);
 extern int setup_hpet_msi_remapped(unsigned int irq, unsigned int id);
+extern void panic_if_irq_remap(const char *msg);
+extern bool setup_remapped_irq(int irq,
+			       struct irq_cfg *cfg,
+			       struct irq_chip *chip);
+
+void irq_remap_modify_chip_defaults(struct irq_chip *chip);
 
 #else  /* CONFIG_IRQ_REMAP */
-
-#define irq_remapping_enabled	0
 
 static inline void setup_irq_remapping_ops(void) { }
 static inline int irq_remapping_supported(void) { return 0; }
···
 {
 	return -ENODEV;
 }
-static inline int set_remapped_irq_affinity(struct irq_data *data,
-					    const struct cpumask *mask,
-					    bool force)
-{
-	return 0;
-}
 static inline void free_remapped_irq(int irq) { }
 static inline void compose_remapped_msi_msg(struct pci_dev *pdev,
 					    unsigned int irq, unsigned int dest,
 					    struct msi_msg *msg, u8 hpet_id)
 {
 }
-static inline int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec)
-{
-	return -ENODEV;
-}
-static inline int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
-					 int index, int sub_handle)
-{
-	return -ENODEV;
-}
 static inline int setup_hpet_msi_remapped(unsigned int irq, unsigned int id)
 {
 	return -ENODEV;
+}
+
+static inline void panic_if_irq_remap(const char *msg)
+{
+}
+
+static inline void irq_remap_modify_chip_defaults(struct irq_chip *chip)
+{
+}
+
+static inline bool setup_remapped_irq(int irq,
+				      struct irq_cfg *cfg,
+				      struct irq_chip *chip)
+{
+	return false;
 }
 #endif /* CONFIG_IRQ_REMAP */
 

arch/x86/include/asm/pci.h

···
 #define arch_teardown_msi_irq x86_teardown_msi_irq
 #define arch_restore_msi_irqs x86_restore_msi_irqs
 /* implemented in arch/x86/kernel/apic/io_apic. */
+struct msi_desc;
 int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type);
 void native_teardown_msi_irq(unsigned int irq);
 void native_restore_msi_irqs(struct pci_dev *dev, int irq);
+int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc,
+		  unsigned int irq_base, unsigned int irq_offset);
 /* default to the implementation in drivers/lib/msi.c */
 #define HAVE_DEFAULT_MSI_TEARDOWN_IRQS
 #define HAVE_DEFAULT_MSI_RESTORE_IRQS

arch/x86/include/asm/x86_init.h

···
 };
 
 struct pci_dev;
+struct msi_msg;
 
 struct x86_msi_ops {
 	int (*setup_msi_irqs)(struct pci_dev *dev, int nvec, int type);
+	void (*compose_msi_msg)(struct pci_dev *dev, unsigned int irq,
+				unsigned int dest, struct msi_msg *msg,
+			       u8 hpet_id);
 	void (*teardown_msi_irq)(unsigned int irq);
 	void (*teardown_msi_irqs)(struct pci_dev *dev);
 	void (*restore_msi_irqs)(struct pci_dev *dev, int irq);
+	int  (*setup_hpet_msi)(unsigned int irq, unsigned int id);
 };
 
+struct IO_APIC_route_entry;
+struct io_apic_irq_attr;
+struct irq_data;
+struct cpumask;
+
 struct x86_io_apic_ops {
-	void		(*init)  (void);
-	unsigned int	(*read)  (unsigned int apic, unsigned int reg);
-	void		(*write) (unsigned int apic, unsigned int reg, unsigned int value);
-	void		(*modify)(unsigned int apic, unsigned int reg, unsigned int value);
+	void		(*init)   (void);
+	unsigned int	(*read)   (unsigned int apic, unsigned int reg);
+	void		(*write)  (unsigned int apic, unsigned int reg, unsigned int value);
+	void		(*modify) (unsigned int apic, unsigned int reg, unsigned int value);
+	void		(*disable)(void);
+	void		(*print_entries)(unsigned int apic, unsigned int nr_entries);
+	int		(*set_affinity)(struct irq_data *data,
+					const struct cpumask *mask,
+					bool force);
+	int		(*setup_entry)(int irq, struct IO_APIC_route_entry *entry,
+				       unsigned int destination, int vector,
+				       struct io_apic_irq_attr *attr);
+	void		(*eoi_ioapic_pin)(int apic, int pin, int vector);
 };
 
 extern struct x86_init_ops x86_init;

arch/x86/kernel/apic/apic.c

···
 	 * Now that local APIC setup is completed for BP, configure the fault
 	 * handling for interrupt remapping.
 	 */
-	if (irq_remapping_enabled)
-		irq_remap_enable_fault_handling();
+	irq_remap_enable_fault_handling();
 
 }
 
···
 	local_irq_save(flags);
 	disable_local_APIC();
 
-	if (irq_remapping_enabled)
-		irq_remapping_disable();
+	irq_remapping_disable();
 
 	local_irq_restore(flags);
 	return 0;
···
 		return;
 
 	local_irq_save(flags);
-	if (irq_remapping_enabled) {
-		/*
-		 * IO-APIC and PIC have their own resume routines.
-		 * We just mask them here to make sure the interrupt
-		 * subsystem is completely quiet while we enable x2apic
-		 * and interrupt-remapping.
-		 */
-		mask_ioapic_entries();
-		legacy_pic->mask_all();
-	}
+
+	/*
+	 * IO-APIC and PIC have their own resume routines.
+	 * We just mask them here to make sure the interrupt
+	 * subsystem is completely quiet while we enable x2apic
+	 * and interrupt-remapping.
+	 */
+	mask_ioapic_entries();
+	legacy_pic->mask_all();
 
 	if (x2apic_mode)
 		enable_x2apic();
···
 	apic_write(APIC_ESR, 0);
 	apic_read(APIC_ESR);
 
-	if (irq_remapping_enabled)
-		irq_remapping_reenable(x2apic_mode);
+	irq_remapping_reenable(x2apic_mode);
 
 	local_irq_restore(flags);
 }

arch/x86/kernel/apic/io_apic.c

···
 #define for_each_irq_pin(entry, head) \
 	for (entry = head; entry; entry = entry->next)
 
-#ifdef CONFIG_IRQ_REMAP
-static void irq_remap_modify_chip_defaults(struct irq_chip *chip);
-static inline bool irq_remapped(struct irq_cfg *cfg)
-{
-	return cfg->irq_2_iommu.iommu != NULL;
-}
-#else
-static inline bool irq_remapped(struct irq_cfg *cfg)
-{
-	return false;
-}
-static inline void irq_remap_modify_chip_defaults(struct irq_chip *chip)
-{
-}
-#endif
-
 /*
  *      Is the SiS APIC rmw bug present ?
  *      -1 = don't know, 0 = no, 1 = yes
···
 		+ (mpc_ioapic_addr(idx) & ~PAGE_MASK);
 }
 
-static inline void io_apic_eoi(unsigned int apic, unsigned int vector)
+void io_apic_eoi(unsigned int apic, unsigned int vector)
 {
 	struct io_apic __iomem *io_apic = io_apic_base(apic);
 	writel(vector, &io_apic->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)
+void native_eoi_ioapic_pin(int apic, int pin, int vector)
 {
 	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);
+		io_apic_eoi(apic, vector);
 	} else {
 		struct IO_APIC_route_entry entry, entry1;
 
···
 	}
 }
 
-static void eoi_ioapic_irq(unsigned int irq, struct irq_cfg *cfg)
+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);
+		x86_io_apic_ops.eoi_ioapic_pin(entry->apic, entry->pin,
+					       cfg->vector);
 	raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 }
 
···
 		}
 
 		raw_spin_lock_irqsave(&ioapic_lock, flags);
-		__eoi_ioapic_pin(apic, pin, entry.vector, NULL);
+		x86_io_apic_ops.eoi_ioapic_pin(apic, pin, entry.vector);
 		raw_spin_unlock_irqrestore(&ioapic_lock, flags);
 	}
 
···
 		fasteoi = false;
 	}
 
-	if (irq_remapped(cfg)) {
-		irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
-		irq_remap_modify_chip_defaults(chip);
+	if (setup_remapped_irq(irq, cfg, chip))
 		fasteoi = trigger != 0;
-	}
 
 	hdl = fasteoi ? handle_fasteoi_irq : handle_edge_irq;
 	irq_set_chip_and_handler_name(irq, chip, hdl,
 				      fasteoi ? "fasteoi" : "edge");
 }
 
-static int setup_ioapic_entry(int irq, struct IO_APIC_route_entry *entry,
-			       unsigned int destination, int vector,
-			       struct io_apic_irq_attr *attr)
+int native_setup_ioapic_entry(int irq, struct IO_APIC_route_entry *entry,
+			      unsigned int destination, int vector,
+			      struct io_apic_irq_attr *attr)
 {
-	if (irq_remapping_enabled)
-		return setup_ioapic_remapped_entry(irq, entry, destination,
-						   vector, attr);
-
 	memset(entry, 0, sizeof(*entry));
 
 	entry->delivery_mode = apic->irq_delivery_mode;
···
 		    attr->ioapic, mpc_ioapic_id(attr->ioapic), attr->ioapic_pin,
 		    cfg->vector, irq, attr->trigger, attr->polarity, dest);
 
-	if (setup_ioapic_entry(irq, &entry, dest, cfg->vector, attr)) {
-		pr_warn("Failed to setup ioapic entry for ioapic %d, pin %d\n",
+	if (x86_io_apic_ops.setup_entry(irq, &entry, dest, cfg->vector, attr)) {
+		pr_warn("Failed to setup ioapic entry for ioapic  %d, pin %d\n",
 			mpc_ioapic_id(attr->ioapic), attr->ioapic_pin);
 		__clear_irq_vector(irq, cfg);
 
···
 	struct IO_APIC_route_entry entry;
 	unsigned int dest;
 
-	if (irq_remapping_enabled)
-		return;
-
 	memset(&entry, 0, sizeof(entry));
 
 	/*
···
 	ioapic_write_entry(ioapic_idx, pin, entry);
 }
 
-__apicdebuginit(void) print_IO_APIC(int ioapic_idx)
+void native_io_apic_print_entries(unsigned int apic, unsigned int nr_entries)
 {
 	int i;
+
+	pr_debug(" NR Dst Mask Trig IRR Pol Stat Dmod Deli Vect:\n");
+
+	for (i = 0; i <= nr_entries; i++) {
+		struct IO_APIC_route_entry entry;
+
+		entry = ioapic_read_entry(apic, i);
+
+		pr_debug(" %02x %02X  ", i, entry.dest);
+		pr_cont("%1d    %1d    %1d   %1d   %1d    "
+			"%1d    %1d    %02X\n",
+			entry.mask,
+			entry.trigger,
+			entry.irr,
+			entry.polarity,
+			entry.delivery_status,
+			entry.dest_mode,
+			entry.delivery_mode,
+			entry.vector);
+	}
+}
+
+void intel_ir_io_apic_print_entries(unsigned int apic,
+				    unsigned int nr_entries)
+{
+	int i;
+
+	pr_debug(" NR Indx Fmt Mask Trig IRR Pol Stat Indx2 Zero Vect:\n");
+
+	for (i = 0; i <= nr_entries; i++) {
+		struct IR_IO_APIC_route_entry *ir_entry;
+		struct IO_APIC_route_entry entry;
+
+		entry = ioapic_read_entry(apic, i);
+
+		ir_entry = (struct IR_IO_APIC_route_entry *)&entry;
+
+		pr_debug(" %02x %04X ", i, ir_entry->index);
+		pr_cont("%1d   %1d    %1d    %1d   %1d   "
+			"%1d    %1d     %X    %02X\n",
+			ir_entry->format,
+			ir_entry->mask,
+			ir_entry->trigger,
+			ir_entry->irr,
+			ir_entry->polarity,
+			ir_entry->delivery_status,
+			ir_entry->index2,
+			ir_entry->zero,
+			ir_entry->vector);
+	}
+}
+
+__apicdebuginit(void) print_IO_APIC(int ioapic_idx)
+{
 	union IO_APIC_reg_00 reg_00;
 	union IO_APIC_reg_01 reg_01;
 	union IO_APIC_reg_02 reg_02;
···
 
 	printk(KERN_DEBUG ".... IRQ redirection table:\n");
 
-	if (irq_remapping_enabled) {
-		printk(KERN_DEBUG " NR Indx Fmt Mask Trig IRR"
-			" Pol Stat Indx2 Zero Vect:\n");
-	} else {
-		printk(KERN_DEBUG " NR Dst Mask Trig IRR Pol"
-			" Stat Dmod Deli Vect:\n");
-	}
-
-	for (i = 0; i <= reg_01.bits.entries; i++) {
-		if (irq_remapping_enabled) {
-			struct IO_APIC_route_entry entry;
-			struct IR_IO_APIC_route_entry *ir_entry;
-
-			entry = ioapic_read_entry(ioapic_idx, i);
-			ir_entry = (struct IR_IO_APIC_route_entry *) &entry;
-			printk(KERN_DEBUG " %02x %04X ",
-				i,
-				ir_entry->index
-			);
-			pr_cont("%1d   %1d    %1d    %1d   %1d   "
-				"%1d    %1d     %X    %02X\n",
-				ir_entry->format,
-				ir_entry->mask,
-				ir_entry->trigger,
-				ir_entry->irr,
-				ir_entry->polarity,
-				ir_entry->delivery_status,
-				ir_entry->index2,
-				ir_entry->zero,
-				ir_entry->vector
-			);
-		} else {
-			struct IO_APIC_route_entry entry;
-
-			entry = ioapic_read_entry(ioapic_idx, i);
-			printk(KERN_DEBUG " %02x %02X  ",
-				i,
-				entry.dest
-			);
-			pr_cont("%1d    %1d    %1d   %1d   %1d    "
-				"%1d    %1d    %02X\n",
-				entry.mask,
-				entry.trigger,
-				entry.irr,
-				entry.polarity,
-				entry.delivery_status,
-				entry.dest_mode,
-				entry.delivery_mode,
-				entry.vector
-			);
-		}
-	}
+	x86_io_apic_ops.print_entries(ioapic_idx, reg_01.bits.entries);
 }
 
 __apicdebuginit(void) print_IO_APICs(void)
···
 	clear_IO_APIC();
 }
 
-/*
- * Not an __init, needed by the reboot code
- */
-void disable_IO_APIC(void)
+void native_disable_io_apic(void)
 {
-	/*
-	 * Clear the IO-APIC before rebooting:
-	 */
-	clear_IO_APIC();
-
-	if (!legacy_pic->nr_legacy_irqs)
-		return;
-
 	/*
 	 * If the i8259 is routed through an IOAPIC
 	 * Put that IOAPIC in virtual wire mode
 	 * so legacy interrupts can be delivered.
-	 *
-	 * With interrupt-remapping, for now we will use virtual wire A mode,
-	 * as virtual wire B is little complex (need to configure both
-	 * IOAPIC RTE as well as interrupt-remapping table entry).
-	 * As this gets called during crash dump, keep this simple for now.
 	 */
-	if (ioapic_i8259.pin != -1 && !irq_remapping_enabled) {
+	if (ioapic_i8259.pin != -1) {
 		struct IO_APIC_route_entry entry;
 
 		memset(&entry, 0, sizeof(entry));
···
 		ioapic_write_entry(ioapic_i8259.apic, ioapic_i8259.pin, entry);
 	}
 
-	/*
-	 * Use virtual wire A mode when interrupt remapping is enabled.
-	 */
 	if (cpu_has_apic || apic_from_smp_config())
-		disconnect_bsp_APIC(!irq_remapping_enabled &&
-				ioapic_i8259.pin != -1);
+		disconnect_bsp_APIC(ioapic_i8259.pin != -1);
+
+}
+
+/*
+ * Not an __init, needed by the reboot code
+ */
+void disable_IO_APIC(void)
+{
+	/*
+	 * Clear the IO-APIC before rebooting:
+	 */
+	clear_IO_APIC();
+
+	if (!legacy_pic->nr_legacy_irqs)
+		return;
+
+	x86_io_apic_ops.disable();
 }
 
 #ifdef CONFIG_X86_32
···
 
 		apic = entry->apic;
 		pin = entry->pin;
-		/*
-		 * With interrupt-remapping, destination information comes
-		 * from interrupt-remapping table entry.
-		 */
-		if (!irq_remapped(cfg))
-			io_apic_write(apic, 0x11 + pin*2, dest);
+
+		io_apic_write(apic, 0x11 + pin*2, dest);
 		reg = io_apic_read(apic, 0x10 + pin*2);
 		reg &= ~IO_APIC_REDIR_VECTOR_MASK;
 		reg |= vector;
···
 	return 0;
 }
 
-static int
-ioapic_set_affinity(struct irq_data *data, const struct cpumask *mask,
-		    bool force)
+
+int native_ioapic_set_affinity(struct irq_data *data,
+			       const struct cpumask *mask,
+			       bool force)
 {
 	unsigned int dest, irq = data->irq;
 	unsigned long flags;
···
 	ioapic_irqd_unmask(data, cfg, masked);
 }
 
-#ifdef CONFIG_IRQ_REMAP
-static void ir_ack_apic_edge(struct irq_data *data)
-{
-	ack_APIC_irq();
-}
-
-static void ir_ack_apic_level(struct irq_data *data)
-{
-	ack_APIC_irq();
-	eoi_ioapic_irq(data->irq, data->chip_data);
-}
-
-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;
-
-	chip->irq_set_affinity = set_remapped_irq_affinity;
-}
-#endif /* CONFIG_IRQ_REMAP */
-
 static struct irq_chip ioapic_chip __read_mostly = {
 	.name			= "IO-APIC",
 	.irq_startup		= startup_ioapic_irq,
···
 	.irq_unmask		= unmask_ioapic_irq,
 	.irq_ack		= ack_apic_edge,
 	.irq_eoi		= ack_apic_level,
-	.irq_set_affinity	= ioapic_set_affinity,
+	.irq_set_affinity	= native_ioapic_set_affinity,
 	.irq_retrigger		= ioapic_retrigger_irq,
 };
 
···
 	 * 8259A.
 	 */
 	if (pin1 == -1) {
-		if (irq_remapping_enabled)
-			panic("BIOS bug: timer not connected to IO-APIC");
+		panic_if_irq_remap("BIOS bug: timer not connected to IO-APIC");
 		pin1 = pin2;
 		apic1 = apic2;
 		no_pin1 = 1;
···
 				clear_IO_APIC_pin(0, pin1);
 			goto out;
 		}
-		if (irq_remapping_enabled)
-			panic("timer doesn't work through Interrupt-remapped IO-APIC");
+		panic_if_irq_remap("timer doesn't work through Interrupt-remapped IO-APIC");
 		local_irq_disable();
 		clear_IO_APIC_pin(apic1, pin1);
 		if (!no_pin1)
···
 
 	irq_set_status_flags(irq, IRQ_NOREQUEST|IRQ_NOPROBE);
 
-	if (irq_remapped(cfg))
-		free_remapped_irq(irq);
+	free_remapped_irq(irq);
+
 	raw_spin_lock_irqsave(&vector_lock, flags);
 	__clear_irq_vector(irq, cfg);
 	raw_spin_unlock_irqrestore(&vector_lock, flags);
 	free_irq_at(irq, cfg);
 }
 
-static inline void destroy_irqs(unsigned int irq, unsigned int count)
+void destroy_irqs(unsigned int irq, unsigned int count)
 {
 	unsigned int i;
 
···
 /*
  * MSI message composition
  */
+void native_compose_msi_msg(struct pci_dev *pdev,
+			    unsigned int irq, unsigned int dest,
+			    struct msi_msg *msg, u8 hpet_id)
+{
+	struct irq_cfg *cfg = irq_cfg(irq);
+
+	msg->address_hi = MSI_ADDR_BASE_HI;
+
+	if (x2apic_enabled())
+		msg->address_hi |= MSI_ADDR_EXT_DEST_ID(dest);
+
+	msg->address_lo =
+		MSI_ADDR_BASE_LO |
+		((apic->irq_dest_mode == 0) ?
+			MSI_ADDR_DEST_MODE_PHYSICAL:
+			MSI_ADDR_DEST_MODE_LOGICAL) |
+		((apic->irq_delivery_mode != dest_LowestPrio) ?
+			MSI_ADDR_REDIRECTION_CPU:
+			MSI_ADDR_REDIRECTION_LOWPRI) |
+		MSI_ADDR_DEST_ID(dest);
+
+	msg->data =
+		MSI_DATA_TRIGGER_EDGE |
+		MSI_DATA_LEVEL_ASSERT |
+		((apic->irq_delivery_mode != dest_LowestPrio) ?
+			MSI_DATA_DELIVERY_FIXED:
+			MSI_DATA_DELIVERY_LOWPRI) |
+		MSI_DATA_VECTOR(cfg->vector);
+}
+
 #ifdef CONFIG_PCI_MSI
 static int msi_compose_msg(struct pci_dev *pdev, unsigned int irq,
 			   struct msi_msg *msg, u8 hpet_id)
···
 	if (err)
 		return err;
 
-	if (irq_remapped(cfg)) {
-		compose_remapped_msi_msg(pdev, irq, dest, msg, hpet_id);
-		return 0;
-	}
-
-	if (x2apic_enabled())
-		msg->address_hi = MSI_ADDR_BASE_HI |
-				  MSI_ADDR_EXT_DEST_ID(dest);
-	else
-		msg->address_hi = MSI_ADDR_BASE_HI;
-
-	msg->address_lo =
-		MSI_ADDR_BASE_LO |
-		((apic->irq_dest_mode == 0) ?
-			MSI_ADDR_DEST_MODE_PHYSICAL:
-			MSI_ADDR_DEST_MODE_LOGICAL) |
-		((apic->irq_delivery_mode != dest_LowestPrio) ?
-			MSI_ADDR_REDIRECTION_CPU:
-			MSI_ADDR_REDIRECTION_LOWPRI) |
-		MSI_ADDR_DEST_ID(dest);
-
-	msg->data =
-		MSI_DATA_TRIGGER_EDGE |
-		MSI_DATA_LEVEL_ASSERT |
-		((apic->irq_delivery_mode != dest_LowestPrio) ?
-			MSI_DATA_DELIVERY_FIXED:
-			MSI_DATA_DELIVERY_LOWPRI) |
-		MSI_DATA_VECTOR(cfg->vector);
+	x86_msi.compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 
 	return 0;
 }
···
 	.irq_retrigger		= ioapic_retrigger_irq,
 };
 
-static int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc,
-			 unsigned int irq_base, unsigned int irq_offset)
+int setup_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc,
+		  unsigned int irq_base, unsigned int irq_offset)
 {
 	struct irq_chip *chip = &msi_chip;
 	struct msi_msg msg;
···
 	if (!irq_offset)
 		write_msi_msg(irq, &msg);
 
-	if (irq_remapped(irq_get_chip_data(irq))) {
-		irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
-		irq_remap_modify_chip_defaults(chip);
-	}
+	setup_remapped_irq(irq, irq_get_chip_data(irq), chip);
 
 	irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "edge");
 
···
 	return 0;
 }
 
-int setup_msix_irqs(struct pci_dev *dev, int nvec)
+int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 {
-	int node, ret, sub_handle, index = 0;
 	unsigned int irq, irq_want;
 	struct msi_desc *msidesc;
+	int node, ret;
+
+	/* Multiple MSI vectors only supported with interrupt remapping */
+	if (type == PCI_CAP_ID_MSI && nvec > 1)
+		return 1;
 
 	node = dev_to_node(&dev->dev);
 	irq_want = nr_irqs_gsi;
-	sub_handle = 0;
 	list_for_each_entry(msidesc, &dev->msi_list, list) {
 		irq = create_irq_nr(irq_want, node);
 		if (irq == 0)
 			return -ENOSPC;
-		irq_want = irq + 1;
-		if (!irq_remapping_enabled)
-			goto no_ir;
 
-		if (!sub_handle) {
-			/*
-			 * allocate the consecutive block of IRTE's
-			 * for 'nvec'
-			 */
-			index = msi_alloc_remapped_irq(dev, irq, nvec);
-			if (index < 0) {
-				ret = index;
-				goto error;
-			}
-		} else {
-			ret = msi_setup_remapped_irq(dev, irq, index,
-						     sub_handle);
-			if (ret < 0)
-				goto error;
-		}
-no_ir:
+		irq_want = irq + 1;
+
 		ret = setup_msi_irq(dev, msidesc, irq, 0);
 		if (ret < 0)
 			goto error;
-		sub_handle++;
 	}
 	return 0;
 
 error:
 	destroy_irq(irq);
 	return ret;
-}
-
-int setup_msi_irqs(struct pci_dev *dev, int nvec)
-{
-	int node, ret, sub_handle, index = 0;
-	unsigned int irq;
-	struct msi_desc *msidesc;
-
-	if (nvec > 1 && !irq_remapping_enabled)
-		return 1;
-
-	nvec = __roundup_pow_of_two(nvec);
-
-	WARN_ON(!list_is_singular(&dev->msi_list));
-	msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
-	WARN_ON(msidesc->irq);
-	WARN_ON(msidesc->msi_attrib.multiple);
-
-	node = dev_to_node(&dev->dev);
-	irq = __create_irqs(nr_irqs_gsi, nvec, node);
-	if (irq == 0)
-		return -ENOSPC;
-
-	if (!irq_remapping_enabled) {
-		ret = setup_msi_irq(dev, msidesc, irq, 0);
-		if (ret < 0)
-			goto error;
-		return 0;
-	}
-
-	msidesc->msi_attrib.multiple = ilog2(nvec);
-	for (sub_handle = 0; sub_handle < nvec; sub_handle++) {
-		if (!sub_handle) {
-			index = msi_alloc_remapped_irq(dev, irq, nvec);
-			if (index < 0) {
-				ret = index;
-				goto error;
-			}
-		} else {
-			ret = msi_setup_remapped_irq(dev, irq + sub_handle,
-						     index, sub_handle);
-			if (ret < 0)
-				goto error;
-		}
-		ret = setup_msi_irq(dev, msidesc, irq, sub_handle);
-		if (ret < 0)
-			goto error;
-	}
-	return 0;
-
-error:
-	destroy_irqs(irq, nvec);
-
-	/*
-	 * Restore altered MSI descriptor fields and prevent just destroyed
-	 * IRQs from tearing down again in default_teardown_msi_irqs()
-	 */
-	msidesc->irq = 0;
-	msidesc->msi_attrib.multiple = 0;
-
-	return ret;
-}
-
-int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
-{
-	if (type == PCI_CAP_ID_MSI)
-		return setup_msi_irqs(dev, nvec);
-	return setup_msix_irqs(dev, nvec);
 }
 
 void native_teardown_msi_irq(unsigned int irq)
···
 	.irq_retrigger = ioapic_retrigger_irq,
 };
 
-int arch_setup_hpet_msi(unsigned int irq, unsigned int id)
+int default_setup_hpet_msi(unsigned int irq, unsigned int id)
 {
 	struct irq_chip *chip = &hpet_msi_type;
 	struct msi_msg msg;
 	int ret;
-
-	if (irq_remapping_enabled) {
-		ret = setup_hpet_msi_remapped(irq, id);
-		if (ret)
-			return ret;
-	}
 
 	ret = msi_compose_msg(NULL, irq, &msg, id);
 	if (ret < 0)
···
 
 	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)))
-		irq_remap_modify_chip_defaults(chip);
+	setup_remapped_irq(irq, irq_get_chip_data(irq), chip);
 
 	irq_set_chip_and_handler_name(irq, chip, handle_edge_irq, "edge");
 	return 0;
···
 		else
 			mask = apic->target_cpus();
 
-		if (irq_remapping_enabled)
-			set_remapped_irq_affinity(idata, mask, false);
-		else
-			ioapic_set_affinity(idata, mask, false);
+		x86_io_apic_ops.set_affinity(idata, mask, false);
 	}
 
 }

arch/x86/kernel/hpet.c

···
 
 static int hpet_setup_msi_irq(unsigned int irq)
 {
-	if (arch_setup_hpet_msi(irq, hpet_blockid)) {
+	if (x86_msi.setup_hpet_msi(irq, hpet_blockid)) {
 		destroy_irq(irq);
 		return -EINVAL;
 	}

arch/x86/kernel/x86_init.c

···
 #include <asm/time.h>
 #include <asm/irq.h>
 #include <asm/io_apic.h>
+#include <asm/hpet.h>
 #include <asm/pat.h>
 #include <asm/tsc.h>
 #include <asm/iommu.h>
···
 
 EXPORT_SYMBOL_GPL(x86_platform);
 struct x86_msi_ops x86_msi = {
-	.setup_msi_irqs = native_setup_msi_irqs,
-	.teardown_msi_irq = native_teardown_msi_irq,
-	.teardown_msi_irqs = default_teardown_msi_irqs,
-	.restore_msi_irqs = default_restore_msi_irqs,
+	.setup_msi_irqs		= native_setup_msi_irqs,
+	.compose_msi_msg	= native_compose_msi_msg,
+	.teardown_msi_irq	= native_teardown_msi_irq,
+	.teardown_msi_irqs	= default_teardown_msi_irqs,
+	.restore_msi_irqs	= default_restore_msi_irqs,
+	.setup_hpet_msi		= default_setup_hpet_msi,
 };
 
 struct x86_io_apic_ops x86_io_apic_ops = {
-	.init	= native_io_apic_init_mappings,
-	.read	= native_io_apic_read,
-	.write	= native_io_apic_write,
-	.modify	= native_io_apic_modify,
+	.init			= native_io_apic_init_mappings,
+	.read			= native_io_apic_read,
+	.write			= native_io_apic_write,
+	.modify			= native_io_apic_modify,
+	.disable		= native_disable_io_apic,
+	.print_entries		= native_io_apic_print_entries,
+	.set_affinity		= native_ioapic_set_affinity,
+	.setup_entry		= native_setup_ioapic_entry,
+	.eoi_ioapic_pin		= native_eoi_ioapic_pin,
 };

drivers/iommu/amd_iommu.c

···
 
 			index -= count - 1;
 
+			cfg->remapped	      = 1;
 			irte_info             = &cfg->irq_2_iommu;
 			irte_info->sub_handle = devid;
 			irte_info->irte_index = index;
-			irte_info->iommu      = (void *)cfg;
 
 			goto out;
 		}
···
 	index = attr->ioapic_pin;
 
 	/* Setup IRQ remapping info */
+	cfg->remapped	      = 1;
 	irte_info->sub_handle = devid;
 	irte_info->irte_index = index;
-	irte_info->iommu      = (void *)cfg;
 
 	/* Setup IRTE for IOMMU */
 	irte.val		= 0;
···
 	devid		= get_device_id(&pdev->dev);
 	irte_info	= &cfg->irq_2_iommu;
 
+	cfg->remapped	      = 1;
 	irte_info->sub_handle = devid;
 	irte_info->irte_index = index + offset;
-	irte_info->iommu      = (void *)cfg;
 
 	return 0;
 }
···
 	if (index < 0)
 		return index;
 
+	cfg->remapped	      = 1;
 	irte_info->sub_handle = devid;
 	irte_info->irte_index = index;
-	irte_info->iommu      = (void *)cfg;
 
 	return 0;
 }

drivers/iommu/dmar.c

···
 #include <asm/irq_remapping.h>
 #include <asm/iommu_table.h>
 
+#include "irq_remapping.h"
+
 /* No locks are needed as DMA remapping hardware unit
  * list is constructed at boot time and hotplug of
  * these units are not supported by the architecture.

drivers/iommu/intel-iommu.c

···
 #include <asm/cacheflush.h>
 #include <asm/iommu.h>
 
+#include "irq_remapping.h"
+
 #define ROOT_SIZE		VTD_PAGE_SIZE
 #define CONTEXT_SIZE		VTD_PAGE_SIZE
 

drivers/iommu/intel_irq_remapping.c

···
 {
 	struct ir_table *table = iommu->ir_table;
 	struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+	struct irq_cfg *cfg = irq_get_chip_data(irq);
 	u16 index, start_index;
 	unsigned int mask = 0;
 	unsigned long flags;
···
 	for (i = index; i < index + count; i++)
 		table->base[i].present = 1;
 
+	cfg->remapped = 1;
 	irq_iommu->iommu = iommu;
 	irq_iommu->irte_index =  index;
 	irq_iommu->sub_handle = 0;
···
 static int set_irte_irq(int irq, struct intel_iommu *iommu, u16 index, u16 subhandle)
 {
 	struct irq_2_iommu *irq_iommu = irq_2_iommu(irq);
+	struct irq_cfg *cfg = irq_get_chip_data(irq);
 	unsigned long flags;
 
 	if (!irq_iommu)
···
 
 	raw_spin_lock_irqsave(&irq_2_ir_lock, flags);
 
+	cfg->remapped = 1;
 	irq_iommu->iommu = iommu;
 	irq_iommu->irte_index = index;
 	irq_iommu->sub_handle = subhandle;
···
 		goto error;
 
 	irq_remapping_enabled = 1;
+
+	/*
+	 * VT-d has a different layout for IO-APIC entries when
+	 * interrupt remapping is enabled. So it needs a special routine
+	 * to print IO-APIC entries for debugging purposes too.
+	 */
+	x86_io_apic_ops.print_entries = intel_ir_io_apic_print_entries;
+
 	pr_info("Enabled IRQ remapping in %s mode\n", eim ? "x2apic" : "xapic");
 
 	return eim ? IRQ_REMAP_X2APIC_MODE : IRQ_REMAP_XAPIC_MODE;

drivers/iommu/irq_remapping.c

···
+#include <linux/seq_file.h>
+#include <linux/cpumask.h>
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/cpumask.h>
 #include <linux/errno.h>
 #include <linux/msi.h>
+#include <linux/irq.h>
+#include <linux/pci.h>
 
 #include <asm/hw_irq.h>
 #include <asm/irq_remapping.h>
+#include <asm/processor.h>
+#include <asm/x86_init.h>
+#include <asm/apic.h>
 
 #include "irq_remapping.h"
 
···
 int no_x2apic_optout;
 
 static struct irq_remap_ops *remap_ops;
+
+static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec);
+static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
+				  int index, int sub_handle);
+static int set_remapped_irq_affinity(struct irq_data *data,
+				     const struct cpumask *mask,
+				     bool force);
+
+static bool irq_remapped(struct irq_cfg *cfg)
+{
+	return (cfg->remapped == 1);
+}
+
+static void irq_remapping_disable_io_apic(void)
+{
+	/*
+	 * With interrupt-remapping, for now we will use virtual wire A
+	 * mode, as virtual wire B is little complex (need to configure
+	 * both IOAPIC RTE as well as interrupt-remapping table entry).
+	 * As this gets called during crash dump, keep this simple for
+	 * now.
+	 */
+	if (cpu_has_apic || apic_from_smp_config())
+		disconnect_bsp_APIC(0);
+}
+
+static int do_setup_msi_irqs(struct pci_dev *dev, int nvec)
+{
+	int node, ret, sub_handle, index = 0;
+	unsigned int irq;
+	struct msi_desc *msidesc;
+
+	nvec = __roundup_pow_of_two(nvec);
+
+	WARN_ON(!list_is_singular(&dev->msi_list));
+	msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
+	WARN_ON(msidesc->irq);
+	WARN_ON(msidesc->msi_attrib.multiple);
+
+	node = dev_to_node(&dev->dev);
+	irq = __create_irqs(get_nr_irqs_gsi(), nvec, node);
+	if (irq == 0)
+		return -ENOSPC;
+
+	msidesc->msi_attrib.multiple = ilog2(nvec);
+	for (sub_handle = 0; sub_handle < nvec; sub_handle++) {
+		if (!sub_handle) {
+			index = msi_alloc_remapped_irq(dev, irq, nvec);
+			if (index < 0) {
+				ret = index;
+				goto error;
+			}
+		} else {
+			ret = msi_setup_remapped_irq(dev, irq + sub_handle,
+						     index, sub_handle);
+			if (ret < 0)
+				goto error;
+		}
+		ret = setup_msi_irq(dev, msidesc, irq, sub_handle);
+		if (ret < 0)
+			goto error;
+	}
+	return 0;
+
+error:
+	destroy_irqs(irq, nvec);
+
+	/*
+	 * Restore altered MSI descriptor fields and prevent just destroyed
+	 * IRQs from tearing down again in default_teardown_msi_irqs()
+	 */
+	msidesc->irq = 0;
+	msidesc->msi_attrib.multiple = 0;
+
+	return ret;
+}
+
+static int do_setup_msix_irqs(struct pci_dev *dev, int nvec)
+{
+	int node, ret, sub_handle, index = 0;
+	struct msi_desc *msidesc;
+	unsigned int irq;
+
+	node		= dev_to_node(&dev->dev);
+	irq		= get_nr_irqs_gsi();
+	sub_handle	= 0;
+
+	list_for_each_entry(msidesc, &dev->msi_list, list) {
+
+		irq = create_irq_nr(irq, node);
+		if (irq == 0)
+			return -1;
+
+		if (sub_handle == 0)
+			ret = index = msi_alloc_remapped_irq(dev, irq, nvec);
+		else
+			ret = msi_setup_remapped_irq(dev, irq, index, sub_handle);
+
+		if (ret < 0)
+			goto error;
+
+		ret = setup_msi_irq(dev, msidesc, irq, 0);
+		if (ret < 0)
+			goto error;
+
+		sub_handle += 1;
+		irq        += 1;
+	}
+
+	return 0;
+
+error:
+	destroy_irq(irq);
+	return ret;
+}
+
+static int irq_remapping_setup_msi_irqs(struct pci_dev *dev,
+					int nvec, int type)
+{
+	if (type == PCI_CAP_ID_MSI)
+		return do_setup_msi_irqs(dev, nvec);
+	else
+		return do_setup_msix_irqs(dev, nvec);
+}
+
+void eoi_ioapic_pin_remapped(int apic, int pin, int vector)
+{
+	/*
+	 * 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.
+	 */
+	io_apic_eoi(apic, pin);
+}
+
+static void __init irq_remapping_modify_x86_ops(void)
+{
+	x86_io_apic_ops.disable		= irq_remapping_disable_io_apic;
+	x86_io_apic_ops.set_affinity	= set_remapped_irq_affinity;
+	x86_io_apic_ops.setup_entry	= setup_ioapic_remapped_entry;
+	x86_io_apic_ops.eoi_ioapic_pin	= eoi_ioapic_pin_remapped;
+	x86_msi.setup_msi_irqs		= irq_remapping_setup_msi_irqs;
+	x86_msi.setup_hpet_msi		= setup_hpet_msi_remapped;
+	x86_msi.compose_msi_msg		= compose_remapped_msi_msg;
+}
 
 static __init int setup_nointremap(char *str)
 {
···
 
 int __init irq_remapping_enable(void)
 {
+	int ret;
+
 	if (!remap_ops || !remap_ops->enable)
 		return -ENODEV;
 
-	return remap_ops->enable();
+	ret = remap_ops->enable();
+
+	if (irq_remapping_enabled)
+		irq_remapping_modify_x86_ops();
+
+	return ret;
 }
 
 void irq_remapping_disable(void)
 {
-	if (!remap_ops || !remap_ops->disable)
+	if (!irq_remapping_enabled ||
+	    !remap_ops ||
+	    !remap_ops->disable)
 		return;
 
 	remap_ops->disable();
···
 
 int irq_remapping_reenable(int mode)
 {
-	if (!remap_ops || !remap_ops->reenable)
+	if (!irq_remapping_enabled ||
+	    !remap_ops ||
+	    !remap_ops->reenable)
 		return 0;
 
 	return remap_ops->reenable(mode);
···
 
 int __init irq_remap_enable_fault_handling(void)
 {
+	if (!irq_remapping_enabled)
+		return 0;
+
 	if (!remap_ops || !remap_ops->enable_faulting)
 		return -ENODEV;
 
···
 
 void free_remapped_irq(int irq)
 {
+	struct irq_cfg *cfg = irq_get_chip_data(irq);
+
 	if (!remap_ops || !remap_ops->free_irq)
 		return;
 
-	remap_ops->free_irq(irq);
+	if (irq_remapped(cfg))
+		remap_ops->free_irq(irq);
 }
 
 void compose_remapped_msi_msg(struct pci_dev *pdev,
 			      unsigned int irq, unsigned int dest,
 			      struct msi_msg *msg, u8 hpet_id)
 {
-	if (!remap_ops || !remap_ops->compose_msi_msg)
-		return;
+	struct irq_cfg *cfg = irq_get_chip_data(irq);
 
-	remap_ops->compose_msi_msg(pdev, irq, dest, msg, hpet_id);
+	if (!irq_remapped(cfg))
+		native_compose_msi_msg(pdev, irq, dest, msg, hpet_id);
+	else if (remap_ops && remap_ops->compose_msi_msg)
+		remap_ops->compose_msi_msg(pdev, irq, dest, msg, hpet_id);
 }
 
-int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec)
+static int msi_alloc_remapped_irq(struct pci_dev *pdev, int irq, int nvec)
 {
 	if (!remap_ops || !remap_ops->msi_alloc_irq)
 		return -ENODEV;
···
 	return remap_ops->msi_alloc_irq(pdev, irq, nvec);
 }
 
-int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
-			   int index, int sub_handle)
+static int msi_setup_remapped_irq(struct pci_dev *pdev, unsigned int irq,
+				  int index, int sub_handle)
 {
 	if (!remap_ops || !remap_ops->msi_setup_irq)
 		return -ENODEV;
···
 		return -ENODEV;
 
 	return remap_ops->setup_hpet_msi(irq, id);
+}
+
+void panic_if_irq_remap(const char *msg)
+{
+	if (irq_remapping_enabled)
+		panic(msg);
+}
+
+static void ir_ack_apic_edge(struct irq_data *data)
+{
+	ack_APIC_irq();
+}
+
+static void ir_ack_apic_level(struct irq_data *data)
+{
+	ack_APIC_irq();
+	eoi_ioapic_irq(data->irq, data->chip_data);
+}
+
+static void ir_print_prefix(struct irq_data *data, struct seq_file *p)
+{
+	seq_printf(p, " IR-%s", data->chip->name);
+}
+
+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;
+	chip->irq_set_affinity = x86_io_apic_ops.set_affinity;
+}
+
+bool setup_remapped_irq(int irq, struct irq_cfg *cfg, struct irq_chip *chip)
+{
+	if (!irq_remapped(cfg))
+		return false;
+	irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
+	irq_remap_modify_chip_defaults(chip);
+	return true;
 }

drivers/iommu/irq_remapping.h

···
 extern int disable_irq_remap;
 extern int disable_sourceid_checking;
 extern int no_x2apic_optout;
+extern int irq_remapping_enabled;
 
 struct irq_remap_ops {
 	/* Check whether Interrupt Remapping is supported */

include/linux/irq.h

···
 
 /* Handle dynamic irq creation and destruction */
 extern unsigned int create_irq_nr(unsigned int irq_want, int node);
+extern unsigned int __create_irqs(unsigned int from, unsigned int count,
+				  int node);
 extern int create_irq(void);
 extern void destroy_irq(unsigned int irq);
+extern void destroy_irqs(unsigned int irq, unsigned int count);
 
 /*
  * Dynamic irq helper functions. Obsolete. Use irq_alloc_desc* and