3 files changed, 138 insertions, 143 deletions

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index 25cd4a07d09f..2a12f3dbdd02 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -226,21 +226,27 @@ static int xen_pcifront_enable_irq(struct pci_dev *dev)
 {
         int rc;
         int share = 1;
+        u8 gsi;
 
-        dev_info(&dev->dev, "Xen PCI enabling IRQ: %d\n", dev->irq);
-
-        if (dev->irq < 0)
-                return -EINVAL;
+        rc = pci_read_config_byte(dev, PCI_INTERRUPT_LINE, &gsi);
+        if (rc < 0) {
+                dev_warn(&dev->dev, "Xen PCI: failed to read interrupt line: %d\n",
+                         rc);
+                return rc;
+        }
 
-        if (dev->irq < NR_IRQS_LEGACY)
+        if (gsi < NR_IRQS_LEGACY)
                 share = 0;
 
-        rc = xen_allocate_pirq(dev->irq, share, "pcifront");
+        rc = xen_allocate_pirq(gsi, share, "pcifront");
         if (rc < 0) {
-                dev_warn(&dev->dev, "Xen PCI IRQ: %d, failed to register:%d\n",
-                         dev->irq, rc);
+                dev_warn(&dev->dev, "Xen PCI: failed to register GSI%d: %d\n",
+                         gsi, rc);
                 return rc;
         }
+
+        dev->irq = rc;
+        dev_info(&dev->dev, "Xen PCI mapped GSI%d to IRQ%d\n", gsi, dev->irq);
         return 0;
 }
 
diff --git a/arch/x86/xen/time.c b/arch/x86/xen/time.c
index 067759e3d6a5..2e2d370a47b1 100644
--- a/arch/x86/xen/time.c
+++ b/arch/x86/xen/time.c
@@ -397,7 +397,9 @@ void xen_setup_timer(int cpu)
                 name = "<timer kasprintf failed>";
 
         irq = bind_virq_to_irqhandler(VIRQ_TIMER, cpu, xen_timer_interrupt,
-                                      IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING|IRQF_TIMER,
+                                      IRQF_DISABLED|IRQF_PERCPU|
+                                      IRQF_NOBALANCING|IRQF_TIMER|
+                                      IRQF_FORCE_RESUME,
                                       name, NULL);
 
         evt = &per_cpu(xen_clock_events, cpu);
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 74681478100a..5aa422a3c3cd 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -277,7 +277,7 @@ static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
 
         BUG_ON(irq == -1);
 #ifdef CONFIG_SMP
-        cpumask_copy(irq_to_desc(irq)->affinity, cpumask_of(cpu));
+        cpumask_copy(irq_to_desc(irq)->irq_data.affinity, cpumask_of(cpu));
 #endif
 
         clear_bit(chn, cpu_evtchn_mask(cpu_from_irq(irq)));
@@ -294,7 +294,7 @@ static void init_evtchn_cpu_bindings(void)
 
         /* By default all event channels notify CPU#0. */
         for_each_irq_desc(i, desc) {
-                cpumask_copy(desc->affinity, cpumask_of(0));
+                cpumask_copy(desc->irq_data.affinity, cpumask_of(0));
         }
 #endif
 
@@ -376,81 +376,69 @@ static void unmask_evtchn(int port)
         put_cpu();
 }
 
-static int get_nr_hw_irqs(void)
+static int xen_allocate_irq_dynamic(void)
 {
-        int ret = 1;
+        int first = 0;
+        int irq;
 
 #ifdef CONFIG_X86_IO_APIC
-        ret = get_nr_irqs_gsi();
+        /*
+         * For an HVM guest or domain 0 which see "real" (emulated or
+         * actual repectively) GSIs we allocate dynamic IRQs
+         * e.g. those corresponding to event channels or MSIs
+         * etc. from the range above those "real" GSIs to avoid
+         * collisions.
+         */
+        if (xen_initial_domain() || xen_hvm_domain())
+                first = get_nr_irqs_gsi();
 #endif
 
-        return ret;
-}
+retry:
+        irq = irq_alloc_desc_from(first, -1);
 
-static int find_unbound_pirq(int type)
-{
-        int rc, i;
-        struct physdev_get_free_pirq op_get_free_pirq;
-        op_get_free_pirq.type = type;
+        if (irq == -ENOMEM && first > NR_IRQS_LEGACY) {
+                printk(KERN_ERR "Out of dynamic IRQ space and eating into GSI space. You should increase nr_irqs\n");
+                first = max(NR_IRQS_LEGACY, first - NR_IRQS_LEGACY);
+                goto retry;
+        }
 
-        rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq, &op_get_free_pirq);
-        if (!rc)
-                return op_get_free_pirq.pirq;
+        if (irq < 0)
+                panic("No available IRQ to bind to: increase nr_irqs!\n");
 
-        for (i = 0; i < nr_irqs; i++) {
-                if (pirq_to_irq[i] < 0)
-                        return i;
-        }
-        return -1;
+        return irq;
 }
 
-static int find_unbound_irq(void)
+static int xen_allocate_irq_gsi(unsigned gsi)
 {
-        struct irq_data *data;
-        int irq, res;
-        int bottom = get_nr_hw_irqs();
-        int top = nr_irqs-1;
-
-        if (bottom == nr_irqs)
-                goto no_irqs;
+        int irq;
 
-        /* This loop starts from the top of IRQ space and goes down.
-         * We need this b/c if we have a PCI device in a Xen PV guest
-         * we do not have an IO-APIC (though the backend might have them)
-         * mapped in. To not have a collision of physical IRQs with the Xen
-         * event channels start at the top of the IRQ space for virtual IRQs.
+        /*
+         * A PV guest has no concept of a GSI (since it has no ACPI
+         * nor access to/knowledge of the physical APICs). Therefore
+         * all IRQs are dynamically allocated from the entire IRQ
+         * space.
          */
-        for (irq = top; irq > bottom; irq--) {
-                data = irq_get_irq_data(irq);
-                /* only 15->0 have init'd desc; handle irq > 16 */
-                if (!data)
-                        break;
-                if (data->chip == &no_irq_chip)
-                        break;
-                if (data->chip != &xen_dynamic_chip)
-                        continue;
-                if (irq_info[irq].type == IRQT_UNBOUND)
-                        return irq;
-        }
-
-        if (irq == bottom)
-                goto no_irqs;
+        if (xen_pv_domain() && !xen_initial_domain())
+                return xen_allocate_irq_dynamic();
 
-        res = irq_alloc_desc_at(irq, -1);
+        /* Legacy IRQ descriptors are already allocated by the arch. */
+        if (gsi < NR_IRQS_LEGACY)
+                return gsi;
 
-        if (WARN_ON(res != irq))
-                return -1;
+        irq = irq_alloc_desc_at(gsi, -1);
+        if (irq < 0)
+                panic("Unable to allocate to IRQ%d (%d)\n", gsi, irq);
 
         return irq;
-
-no_irqs:
-        panic("No available IRQ to bind to: increase nr_irqs!\n");
 }
 
-static bool identity_mapped_irq(unsigned irq)
+static void xen_free_irq(unsigned irq)
 {
-        /* identity map all the hardware irqs */
-        return irq < get_nr_hw_irqs();
+        /* Legacy IRQ descriptors are managed by the arch. */
+        if (irq < NR_IRQS_LEGACY)
+                return;
+
+        irq_free_desc(irq);
 }
 
 static void pirq_unmask_notify(int irq)
@@ -486,7 +474,7 @@ static bool probing_irq(int irq)
         return desc && desc->action == NULL;
 }
 
-static unsigned int startup_pirq(unsigned int irq)
+static unsigned int __startup_pirq(unsigned int irq)
 {
         struct evtchn_bind_pirq bind_pirq;
         struct irq_info *info = info_for_irq(irq);
@@ -524,9 +512,15 @@ out:
         return 0;
 }
 
-static void shutdown_pirq(unsigned int irq)
+static unsigned int startup_pirq(struct irq_data *data)
+{
+        return __startup_pirq(data->irq);
+}
+
+static void shutdown_pirq(struct irq_data *data)
 {
         struct evtchn_close close;
+        unsigned int irq = data->irq;
         struct irq_info *info = info_for_irq(irq);
         int evtchn = evtchn_from_irq(irq);
 
@@ -546,20 +540,20 @@ static void shutdown_pirq(unsigned int irq)
         info->evtchn = 0;
 }
 
-static void enable_pirq(unsigned int irq)
+static void enable_pirq(struct irq_data *data)
 {
-        startup_pirq(irq);
+        startup_pirq(data);
 }
 
-static void disable_pirq(unsigned int irq)
+static void disable_pirq(struct irq_data *data)
 {
 }
 
-static void ack_pirq(unsigned int irq)
+static void ack_pirq(struct irq_data *data)
 {
-        int evtchn = evtchn_from_irq(irq);
+        int evtchn = evtchn_from_irq(data->irq);
 
-        move_native_irq(irq);
+        move_native_irq(data->irq);
 
         if (VALID_EVTCHN(evtchn)) {
                 mask_evtchn(evtchn);
@@ -567,23 +561,6 @@ static void ack_pirq(unsigned int irq)
         }
 }
 
-static void end_pirq(unsigned int irq)
-{
-        int evtchn = evtchn_from_irq(irq);
-        struct irq_desc *desc = irq_to_desc(irq);
-
-        if (WARN_ON(!desc))
-                return;
-
-        if ((desc->status & (IRQ_DISABLED|IRQ_PENDING)) ==
-            (IRQ_DISABLED|IRQ_PENDING)) {
-                shutdown_pirq(irq);
-        } else if (VALID_EVTCHN(evtchn)) {
-                unmask_evtchn(evtchn);
-                pirq_unmask_notify(irq);
-        }
-}
-
 static int find_irq_by_gsi(unsigned gsi)
 {
         int irq;
@@ -638,14 +615,7 @@ int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name)
                 goto out;       /* XXX need refcount? */
         }
 
-        /* If we are a PV guest, we don't have GSIs (no ACPI passed). Therefore
-         * we are using the !xen_initial_domain() to drop in the function.*/
-        if (identity_mapped_irq(gsi) || (!xen_initial_domain() &&
-                                xen_pv_domain())) {
-                irq = gsi;
-                irq_alloc_desc_at(irq, -1);
-        } else
-                irq = find_unbound_irq();
+        irq = xen_allocate_irq_gsi(gsi);
 
         set_irq_chip_and_handler_name(irq, &xen_pirq_chip,
                                       handle_level_irq, name);
@@ -658,7 +628,7 @@ int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name)
          * this in the priv domain. */
         if (xen_initial_domain() &&
             HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) {
-                irq_free_desc(irq);
+                xen_free_irq(irq);
                 irq = -ENOSPC;
                 goto out;
         }
@@ -677,12 +647,29 @@ out:
 #include <linux/msi.h>
 #include "../pci/msi.h"
 
+static int find_unbound_pirq(int type)
+{
+        int rc, i;
+        struct physdev_get_free_pirq op_get_free_pirq;
+        op_get_free_pirq.type = type;
+
+        rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_free_pirq, &op_get_free_pirq);
+        if (!rc)
+                return op_get_free_pirq.pirq;
+
+        for (i = 0; i < nr_irqs; i++) {
+                if (pirq_to_irq[i] < 0)
+                        return i;
+        }
+        return -1;
+}
+
 void xen_allocate_pirq_msi(char *name, int *irq, int *pirq, int alloc)
 {
         spin_lock(&irq_mapping_update_lock);
 
         if (alloc & XEN_ALLOC_IRQ) {
-                *irq = find_unbound_irq();
+                *irq = xen_allocate_irq_dynamic();
                 if (*irq == -1)
                         goto out;
         }
@@ -732,7 +719,7 @@ int xen_create_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int type)
 
         spin_lock(&irq_mapping_update_lock);
 
-        irq = find_unbound_irq();
+        irq = xen_allocate_irq_dynamic();
 
         if (irq == -1)
                 goto out;
@@ -741,7 +728,7 @@ int xen_create_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int type)
         if (rc) {
                 printk(KERN_WARNING "xen map irq failed %d\n", rc);
 
-                irq_free_desc(irq);
+                xen_free_irq(irq);
 
                 irq = -1;
                 goto out;
@@ -783,7 +770,7 @@ int xen_destroy_irq(int irq)
         }
         irq_info[irq] = mk_unbound_info();
 
-        irq_free_desc(irq);
+        xen_free_irq(irq);
 
 out:
         spin_unlock(&irq_mapping_update_lock);
@@ -814,7 +801,7 @@ int bind_evtchn_to_irq(unsigned int evtchn)
         irq = evtchn_to_irq[evtchn];
 
         if (irq == -1) {
-                irq = find_unbound_irq();
+                irq = xen_allocate_irq_dynamic();
 
                 set_irq_chip_and_handler_name(irq, &xen_dynamic_chip,
                                               handle_fasteoi_irq, "event");
@@ -839,7 +826,7 @@ static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
         irq = per_cpu(ipi_to_irq, cpu)[ipi];
 
         if (irq == -1) {
-                irq = find_unbound_irq();
+                irq = xen_allocate_irq_dynamic();
                 if (irq < 0)
                         goto out;
 
@@ -875,7 +862,7 @@ int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
         irq = per_cpu(virq_to_irq, cpu)[virq];
 
         if (irq == -1) {
-                irq = find_unbound_irq();
+                irq = xen_allocate_irq_dynamic();
 
                 set_irq_chip_and_handler_name(irq, &xen_percpu_chip,
                                               handle_percpu_irq, "virq");
@@ -934,7 +921,7 @@ static void unbind_from_irq(unsigned int irq)
         if (irq_info[irq].type != IRQT_UNBOUND) {
                 irq_info[irq] = mk_unbound_info();
 
-                irq_free_desc(irq);
+                xen_free_irq(irq);
         }
 
         spin_unlock(&irq_mapping_update_lock);
@@ -1234,11 +1221,12 @@ static int rebind_irq_to_cpu(unsigned irq, unsigned tcpu)
         return 0;
 }
 
-static int set_affinity_irq(unsigned irq, const struct cpumask *dest)
+static int set_affinity_irq(struct irq_data *data, const struct cpumask *dest,
+                            bool force)
 {
         unsigned tcpu = cpumask_first(dest);
 
-        return rebind_irq_to_cpu(irq, tcpu);
+        return rebind_irq_to_cpu(data->irq, tcpu);
 }
 
 int resend_irq_on_evtchn(unsigned int irq)
@@ -1257,35 +1245,35 @@ int resend_irq_on_evtchn(unsigned int irq)
         return 1;
 }
 
-static void enable_dynirq(unsigned int irq)
+static void enable_dynirq(struct irq_data *data)
 {
-        int evtchn = evtchn_from_irq(irq);
+        int evtchn = evtchn_from_irq(data->irq);
 
         if (VALID_EVTCHN(evtchn))
                 unmask_evtchn(evtchn);
 }
 
-static void disable_dynirq(unsigned int irq)
+static void disable_dynirq(struct irq_data *data)
 {
-        int evtchn = evtchn_from_irq(irq);
+        int evtchn = evtchn_from_irq(data->irq);
 
         if (VALID_EVTCHN(evtchn))
                 mask_evtchn(evtchn);
 }
 
-static void ack_dynirq(unsigned int irq)
+static void ack_dynirq(struct irq_data *data)
 {
-        int evtchn = evtchn_from_irq(irq);
+        int evtchn = evtchn_from_irq(data->irq);
 
-        move_masked_irq(irq);
+        move_masked_irq(data->irq);
 
         if (VALID_EVTCHN(evtchn))
                 unmask_evtchn(evtchn);
 }
 
-static int retrigger_dynirq(unsigned int irq)
+static int retrigger_dynirq(struct irq_data *data)
 {
-        int evtchn = evtchn_from_irq(irq);
+        int evtchn = evtchn_from_irq(data->irq);
         struct shared_info *sh = HYPERVISOR_shared_info;
         int ret = 0;
 
@@ -1334,7 +1322,7 @@ static void restore_cpu_pirqs(void)
 
                 printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
 
-                startup_pirq(irq);
+                __startup_pirq(irq);
         }
 }
 
@@ -1486,45 +1474,44 @@ void xen_irq_resume(void)
 }
 
 static struct irq_chip xen_dynamic_chip __read_mostly = {
-        .name           = "xen-dyn",
+        .name                   = "xen-dyn",
 
-        .disable        = disable_dynirq,
-        .mask           = disable_dynirq,
-        .unmask         = enable_dynirq,
+        .irq_disable            = disable_dynirq,
+        .irq_mask               = disable_dynirq,
+        .irq_unmask             = enable_dynirq,
 
-        .eoi            = ack_dynirq,
-        .set_affinity   = set_affinity_irq,
-        .retrigger      = retrigger_dynirq,
+        .irq_eoi                = ack_dynirq,
+        .irq_set_affinity       = set_affinity_irq,
+        .irq_retrigger          = retrigger_dynirq,
 };
 
 static struct irq_chip xen_pirq_chip __read_mostly = {
-        .name           = "xen-pirq",
+        .name                   = "xen-pirq",
 
-        .startup        = startup_pirq,
-        .shutdown       = shutdown_pirq,
+        .irq_startup            = startup_pirq,
+        .irq_shutdown           = shutdown_pirq,
 
-        .enable         = enable_pirq,
-        .unmask         = enable_pirq,
+        .irq_enable             = enable_pirq,
+        .irq_unmask             = enable_pirq,
 
-        .disable        = disable_pirq,
-        .mask           = disable_pirq,
+        .irq_disable            = disable_pirq,
+        .irq_mask               = disable_pirq,
 
-        .ack            = ack_pirq,
-        .end            = end_pirq,
+        .irq_ack                = ack_pirq,
 
-        .set_affinity   = set_affinity_irq,
+        .irq_set_affinity       = set_affinity_irq,
 
-        .retrigger      = retrigger_dynirq,
+        .irq_retrigger          = retrigger_dynirq,
 };
 
 static struct irq_chip xen_percpu_chip __read_mostly = {
-        .name           = "xen-percpu",
+        .name                   = "xen-percpu",
 
-        .disable        = disable_dynirq,
-        .mask           = disable_dynirq,
-        .unmask         = enable_dynirq,
+        .irq_disable            = disable_dynirq,
+        .irq_mask               = disable_dynirq,
+        .irq_unmask             = enable_dynirq,
 
-        .ack            = ack_dynirq,
+        .irq_ack                = ack_dynirq,
 };
 
 int xen_set_callback_via(uint64_t via)