1 files changed, 76 insertions, 33 deletions

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 2811bb988ea0..31af0ac31a98 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -105,7 +105,6 @@ struct irq_info
 
 static struct irq_info *irq_info;
 static int *pirq_to_irq;
-static int nr_pirqs;
 
 static int *evtchn_to_irq;
 struct cpu_evtchn_s {
@@ -385,12 +384,17 @@ static int get_nr_hw_irqs(void)
         return ret;
 }
 
-/* callers of this function should make sure that PHYSDEVOP_get_nr_pirqs
- * succeeded otherwise nr_pirqs won't hold the right value */
-static int find_unbound_pirq(void)
+static int find_unbound_pirq(int type)
 {
-        int i;
-        for (i = nr_pirqs-1; i >= 0; i--) {
+        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;
         }
@@ -423,7 +427,7 @@ static int find_unbound_irq(void)
         if (irq == start)
                 goto no_irqs;
 
-        res = irq_alloc_desc_at(irq, 0);
+        res = irq_alloc_desc_at(irq, -1);
 
         if (WARN_ON(res != irq))
                 return -1;
@@ -611,10 +615,10 @@ int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name)
 
         spin_lock(&irq_mapping_update_lock);
 
-        if ((pirq > nr_pirqs) || (gsi > nr_irqs)) {
+        if ((pirq > nr_irqs) || (gsi > nr_irqs)) {
                 printk(KERN_WARNING "xen_map_pirq_gsi: %s %s is incorrect!\n",
-                        pirq > nr_pirqs ? "nr_pirqs" :"",
-                        gsi > nr_irqs ? "nr_irqs" : "");
+                        pirq > nr_irqs ? "pirq" :"",
+                        gsi > nr_irqs ? "gsi" : "");
                 goto out;
         }
 
@@ -630,7 +634,7 @@ int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name)
         if (identity_mapped_irq(gsi) || (!xen_initial_domain() &&
                                 xen_pv_domain())) {
                 irq = gsi;
-                irq_alloc_desc_at(irq, 0);
+                irq_alloc_desc_at(irq, -1);
         } else
                 irq = find_unbound_irq();
 
@@ -664,17 +668,21 @@ out:
 #include <linux/msi.h>
 #include "../pci/msi.h"
 
-void xen_allocate_pirq_msi(char *name, int *irq, int *pirq)
+void xen_allocate_pirq_msi(char *name, int *irq, int *pirq, int alloc)
 {
         spin_lock(&irq_mapping_update_lock);
 
-        *irq = find_unbound_irq();
-        if (*irq == -1)
-                goto out;
+        if (alloc & XEN_ALLOC_IRQ) {
+                *irq = find_unbound_irq();
+                if (*irq == -1)
+                        goto out;
+        }
 
-        *pirq = find_unbound_pirq();
-        if (*pirq == -1)
-                goto out;
+        if (alloc & XEN_ALLOC_PIRQ) {
+                *pirq = find_unbound_pirq(MAP_PIRQ_TYPE_MSI);
+                if (*pirq == -1)
+                        goto out;
+        }
 
         set_irq_chip_and_handler_name(*irq, &xen_pirq_chip,
                                       handle_level_irq, name);
@@ -762,6 +770,7 @@ int xen_destroy_irq(int irq)
                         printk(KERN_WARNING "unmap irq failed %d\n", rc);
                         goto out;
                 }
+                pirq_to_irq[info->u.pirq.pirq] = -1;
         }
         irq_info[irq] = mk_unbound_info();
 
@@ -782,6 +791,11 @@ int xen_gsi_from_irq(unsigned irq)
         return gsi_from_irq(irq);
 }
 
+int xen_irq_from_pirq(unsigned pirq)
+{
+        return pirq_to_irq[pirq];
+}
+
 int bind_evtchn_to_irq(unsigned int evtchn)
 {
         int irq;
@@ -1279,6 +1293,42 @@ static int retrigger_dynirq(unsigned int irq)
         return ret;
 }
 
+static void restore_cpu_pirqs(void)
+{
+        int pirq, rc, irq, gsi;
+        struct physdev_map_pirq map_irq;
+
+        for (pirq = 0; pirq < nr_irqs; pirq++) {
+                irq = pirq_to_irq[pirq];
+                if (irq == -1)
+                        continue;
+
+                /* save/restore of PT devices doesn't work, so at this point the
+                 * only devices present are GSI based emulated devices */
+                gsi = gsi_from_irq(irq);
+                if (!gsi)
+                        continue;
+
+                map_irq.domid = DOMID_SELF;
+                map_irq.type = MAP_PIRQ_TYPE_GSI;
+                map_irq.index = gsi;
+                map_irq.pirq = pirq;
+
+                rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
+                if (rc) {
+                        printk(KERN_WARNING "xen map irq failed gsi=%d irq=%d pirq=%d rc=%d\n",
+                                        gsi, irq, pirq, rc);
+                        irq_info[irq] = mk_unbound_info();
+                        pirq_to_irq[pirq] = -1;
+                        continue;
+                }
+
+                printk(KERN_DEBUG "xen: --> irq=%d, pirq=%d\n", irq, map_irq.pirq);
+
+                startup_pirq(irq);
+        }
+}
+
 static void restore_cpu_virqs(unsigned int cpu)
 {
         struct evtchn_bind_virq bind_virq;
@@ -1422,6 +1472,8 @@ void xen_irq_resume(void)
 
                 unmask_evtchn(evtchn);
         }
+
+        restore_cpu_pirqs();
 }
 
 static struct irq_chip xen_dynamic_chip __read_mostly = {
@@ -1506,26 +1558,17 @@ void xen_callback_vector(void) {}
 
 void __init xen_init_IRQ(void)
 {
-        int i, rc;
-        struct physdev_nr_pirqs op_nr_pirqs;
+        int i;
 
         cpu_evtchn_mask_p = kcalloc(nr_cpu_ids, sizeof(struct cpu_evtchn_s),
                                     GFP_KERNEL);
         irq_info = kcalloc(nr_irqs, sizeof(*irq_info), GFP_KERNEL);
 
-        rc = HYPERVISOR_physdev_op(PHYSDEVOP_get_nr_pirqs, &op_nr_pirqs);
-        if (rc < 0) {
-                nr_pirqs = nr_irqs;
-                if (rc != -ENOSYS)
-                        printk(KERN_WARNING "PHYSDEVOP_get_nr_pirqs returned rc=%d\n", rc);
-        } else {
-                if (xen_pv_domain() && !xen_initial_domain())
-                        nr_pirqs = max((int)op_nr_pirqs.nr_pirqs, nr_irqs);
-                else
-                        nr_pirqs = op_nr_pirqs.nr_pirqs;
-        }
-        pirq_to_irq = kcalloc(nr_pirqs, sizeof(*pirq_to_irq), GFP_KERNEL);
-        for (i = 0; i < nr_pirqs; i++)
+        /* We are using nr_irqs as the maximum number of pirq available but
+         * that number is actually chosen by Xen and we don't know exactly
+         * what it is. Be careful choosing high pirq numbers. */
+        pirq_to_irq = kcalloc(nr_irqs, sizeof(*pirq_to_irq), GFP_KERNEL);
+        for (i = 0; i < nr_irqs; i++)
                 pirq_to_irq[i] = -1;
 
         evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq),