1 files changed, 73 insertions, 40 deletions

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 33167b43ac7..0ae1d4d7e18 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -118,6 +118,8 @@ static DEFINE_PER_CPU(unsigned long [NR_EVENT_CHANNELS/BITS_PER_LONG],
 static struct irq_chip xen_dynamic_chip;
 static struct irq_chip xen_percpu_chip;
 static struct irq_chip xen_pirq_chip;
+static void enable_dynirq(struct irq_data *data);
+static void disable_dynirq(struct irq_data *data);
 
 /* Get info for IRQ */
 static struct irq_info *info_for_irq(unsigned irq)
@@ -473,16 +475,6 @@ static void xen_free_irq(unsigned irq)
         irq_free_desc(irq);
 }
 
-static void pirq_unmask_notify(int irq)
-{
-        struct physdev_eoi eoi = { .irq = pirq_from_irq(irq) };
-
-        if (unlikely(pirq_needs_eoi(irq))) {
-                int rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
-                WARN_ON(rc);
-        }
-}
-
 static void pirq_query_unmask(int irq)
 {
         struct physdev_irq_status_query irq_status;
@@ -506,6 +498,29 @@ static bool probing_irq(int irq)
         return desc && desc->action == NULL;
 }
 
+static void eoi_pirq(struct irq_data *data)
+{
+        int evtchn = evtchn_from_irq(data->irq);
+        struct physdev_eoi eoi = { .irq = pirq_from_irq(data->irq) };
+        int rc = 0;
+
+        irq_move_irq(data);
+
+        if (VALID_EVTCHN(evtchn))
+                clear_evtchn(evtchn);
+
+        if (pirq_needs_eoi(data->irq)) {
+                rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
+                WARN_ON(rc);
+        }
+}
+
+static void mask_ack_pirq(struct irq_data *data)
+{
+        disable_dynirq(data);
+        eoi_pirq(data);
+}
+
 static unsigned int __startup_pirq(unsigned int irq)
 {
         struct evtchn_bind_pirq bind_pirq;
@@ -539,7 +554,7 @@ static unsigned int __startup_pirq(unsigned int irq)
 
 out:
         unmask_evtchn(evtchn);
-        pirq_unmask_notify(irq);
+        eoi_pirq(irq_get_irq_data(irq));
 
         return 0;
 }
@@ -579,18 +594,7 @@ static void enable_pirq(struct irq_data *data)
 
 static void disable_pirq(struct irq_data *data)
 {
-}
-
-static void ack_pirq(struct irq_data *data)
-{
-        int evtchn = evtchn_from_irq(data->irq);
-
-        irq_move_irq(data);
-
-        if (VALID_EVTCHN(evtchn)) {
-                mask_evtchn(evtchn);
-                clear_evtchn(evtchn);
-        }
+        disable_dynirq(data);
 }
 
 static int find_irq_by_gsi(unsigned gsi)
@@ -639,9 +643,6 @@ int xen_bind_pirq_gsi_to_irq(unsigned gsi,
         if (irq < 0)
                 goto out;
 
-        irq_set_chip_and_handler_name(irq, &xen_pirq_chip, handle_level_irq,
-                                      name);
-
         irq_op.irq = irq;
         irq_op.vector = 0;
 
@@ -658,6 +659,32 @@ int xen_bind_pirq_gsi_to_irq(unsigned gsi,
         xen_irq_info_pirq_init(irq, 0, pirq, gsi, irq_op.vector,
                                shareable ? PIRQ_SHAREABLE : 0);
 
+        pirq_query_unmask(irq);
+        /* We try to use the handler with the appropriate semantic for the
+         * type of interrupt: if the interrupt doesn't need an eoi
+         * (pirq_needs_eoi returns false), we treat it like an edge
+         * triggered interrupt so we use handle_edge_irq.
+         * As a matter of fact this only happens when the corresponding
+         * physical interrupt is edge triggered or an msi.
+         *
+         * On the other hand if the interrupt needs an eoi (pirq_needs_eoi
+         * returns true) we treat it like a level triggered interrupt so we
+         * use handle_fasteoi_irq like the native code does for this kind of
+         * interrupts.
+         * Depending on the Xen version, pirq_needs_eoi might return true
+         * not only for level triggered interrupts but for edge triggered
+         * interrupts too. In any case Xen always honors the eoi mechanism,
+         * not injecting any more pirqs of the same kind if the first one
+         * hasn't received an eoi yet. Therefore using the fasteoi handler
+         * is the right choice either way.
+         */
+        if (pirq_needs_eoi(irq))
+                irq_set_chip_and_handler_name(irq, &xen_pirq_chip,
+                                handle_fasteoi_irq, name);
+        else
+                irq_set_chip_and_handler_name(irq, &xen_pirq_chip,
+                                handle_edge_irq, name);
+
 out:
         spin_unlock(&irq_mapping_update_lock);
 
@@ -690,8 +717,8 @@ int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc,
         if (irq == -1)
                 goto out;
 
-        irq_set_chip_and_handler_name(irq, &xen_pirq_chip, handle_level_irq,
-                                      name);
+        irq_set_chip_and_handler_name(irq, &xen_pirq_chip, handle_edge_irq,
+                        name);
 
         xen_irq_info_pirq_init(irq, 0, pirq, 0, vector, 0);
         ret = irq_set_msi_desc(irq, msidesc);
@@ -773,7 +800,7 @@ int bind_evtchn_to_irq(unsigned int evtchn)
                         goto out;
 
                 irq_set_chip_and_handler_name(irq, &xen_dynamic_chip,
-                                              handle_fasteoi_irq, "event");
+                                              handle_edge_irq, "event");
 
                 xen_irq_info_evtchn_init(irq, evtchn);
         }
@@ -1179,9 +1206,6 @@ static void __xen_evtchn_do_upcall(void)
                                 port = (word_idx * BITS_PER_LONG) + bit_idx;
                                 irq = evtchn_to_irq[port];
 
-                                mask_evtchn(port);
-                                clear_evtchn(port);
-
                                 if (irq != -1) {
                                         desc = irq_to_desc(irq);
                                         if (desc)
@@ -1337,10 +1361,16 @@ static void ack_dynirq(struct irq_data *data)
 {
         int evtchn = evtchn_from_irq(data->irq);
 
-        irq_move_masked_irq(data);
+        irq_move_irq(data);
 
         if (VALID_EVTCHN(evtchn))
-                unmask_evtchn(evtchn);
+                clear_evtchn(evtchn);
+}
+
+static void mask_ack_dynirq(struct irq_data *data)
+{
+        disable_dynirq(data);
+        ack_dynirq(data);
 }
 
 static int retrigger_dynirq(struct irq_data *data)
@@ -1535,7 +1565,9 @@ static struct irq_chip xen_dynamic_chip __read_mostly = {
         .irq_mask               = disable_dynirq,
         .irq_unmask             = enable_dynirq,
 
-        .irq_eoi                = ack_dynirq,
+        .irq_ack                = ack_dynirq,
+        .irq_mask_ack           = mask_ack_dynirq,
+
         .irq_set_affinity       = set_affinity_irq,
         .irq_retrigger          = retrigger_dynirq,
 };
@@ -1545,14 +1577,15 @@ static struct irq_chip xen_pirq_chip __read_mostly = {
 
         .irq_startup            = startup_pirq,
         .irq_shutdown           = shutdown_pirq,
-
         .irq_enable             = enable_pirq,
-        .irq_unmask             = enable_pirq,
-
         .irq_disable            = disable_pirq,
-        .irq_mask               = disable_pirq,
 
-        .irq_ack                = ack_pirq,
+        .irq_mask               = disable_dynirq,
+        .irq_unmask             = enable_dynirq,
+
+        .irq_ack                = eoi_pirq,
+        .irq_eoi                = eoi_pirq,
+        .irq_mask_ack           = mask_ack_pirq,
 
         .irq_set_affinity       = set_affinity_irq,