]> Pileus Git - ~andy/linux/blobdiff - drivers/xen/events.c
Merge branches 'stable/irq', 'stable/p2m.bugfixes', 'stable/e820.bugfixes' and 'stabl...
[~andy/linux] / drivers / xen / events.c
index 036343ba204eaab47758641c8657cb37bba08f54..3ff822b481454847487b2c3eeaaa18d354f33721 100644 (file)
@@ -5,7 +5,7 @@
  * domain gets 1024 event channels, but NR_IRQ is not that large, we
  * must dynamically map irqs<->event channels.  The event channels
  * interface with the rest of the kernel by defining a xen interrupt
- * chip.  When an event is recieved, it is mapped to an irq and sent
+ * chip.  When an event is received, it is mapped to an irq and sent
  * through the normal interrupt processing path.
  *
  * There are four kinds of events which can be mapped to an event
@@ -101,6 +101,7 @@ struct irq_info
                        unsigned short gsi;
                        unsigned char vector;
                        unsigned char flags;
+                       uint16_t domid;
                } pirq;
        } u;
 };
@@ -118,6 +119,8 @@ 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)
@@ -184,6 +187,7 @@ static void xen_irq_info_pirq_init(unsigned irq,
                                   unsigned short pirq,
                                   unsigned short gsi,
                                   unsigned short vector,
+                                  uint16_t domid,
                                   unsigned char flags)
 {
        struct irq_info *info = info_for_irq(irq);
@@ -193,6 +197,7 @@ static void xen_irq_info_pirq_init(unsigned irq,
        info->u.pirq.pirq = pirq;
        info->u.pirq.gsi = gsi;
        info->u.pirq.vector = vector;
+       info->u.pirq.domid = domid;
        info->u.pirq.flags = flags;
 }
 
@@ -416,7 +421,7 @@ static int __must_check xen_allocate_irq_dynamic(void)
 #ifdef CONFIG_X86_IO_APIC
        /*
         * For an HVM guest or domain 0 which see "real" (emulated or
-        * actual repectively) GSIs we allocate dynamic IRQs
+        * actual respectively) 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.
@@ -473,16 +478,6 @@ 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 +501,29 @@ 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 +557,7 @@ 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 +597,7 @@ 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 +646,6 @@ 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;
 
@@ -655,9 +659,35 @@ int xen_bind_pirq_gsi_to_irq(unsigned gsi,
                goto out;
        }
 
-       xen_irq_info_pirq_init(irq, 0, pirq, gsi, irq_op.vector,
+       xen_irq_info_pirq_init(irq, 0, pirq, gsi, irq_op.vector, DOMID_SELF,
                               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);
 
@@ -680,7 +710,8 @@ int xen_allocate_pirq_msi(struct pci_dev *dev, struct msi_desc *msidesc)
 }
 
 int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc,
-                            int pirq, int vector, const char *name)
+                            int pirq, int vector, const char *name,
+                            domid_t domid)
 {
        int irq, ret;
 
@@ -690,10 +721,10 @@ 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);
+       xen_irq_info_pirq_init(irq, 0, pirq, 0, vector, domid, 0);
        ret = irq_set_msi_desc(irq, msidesc);
        if (ret < 0)
                goto error_irq;
@@ -722,9 +753,16 @@ int xen_destroy_irq(int irq)
 
        if (xen_initial_domain()) {
                unmap_irq.pirq = info->u.pirq.pirq;
-               unmap_irq.domid = DOMID_SELF;
+               unmap_irq.domid = info->u.pirq.domid;
                rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq);
-               if (rc) {
+               /* If another domain quits without making the pci_disable_msix
+                * call, the Xen hypervisor takes care of freeing the PIRQs
+                * (free_domain_pirqs).
+                */
+               if ((rc == -ESRCH && info->u.pirq.domid != DOMID_SELF))
+                       printk(KERN_INFO "domain %d does not have %d anymore\n",
+                               info->u.pirq.domid, info->u.pirq.pirq);
+               else if (rc) {
                        printk(KERN_WARNING "unmap irq failed %d\n", rc);
                        goto out;
                }
@@ -759,6 +797,12 @@ out:
        return irq;
 }
 
+
+int xen_pirq_from_irq(unsigned irq)
+{
+       return pirq_from_irq(irq);
+}
+EXPORT_SYMBOL_GPL(xen_pirq_from_irq);
 int bind_evtchn_to_irq(unsigned int evtchn)
 {
        int irq;
@@ -773,7 +817,7 @@ 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);
        }
@@ -912,8 +956,7 @@ int bind_evtchn_to_irqhandler(unsigned int evtchn,
                              unsigned long irqflags,
                              const char *devname, void *dev_id)
 {
-       unsigned int irq;
-       int retval;
+       int irq, retval;
 
        irq = bind_evtchn_to_irq(evtchn);
        if (irq < 0)
@@ -955,8 +998,7 @@ int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
                            irq_handler_t handler,
                            unsigned long irqflags, const char *devname, void *dev_id)
 {
-       unsigned int irq;
-       int retval;
+       int irq, retval;
 
        irq = bind_virq_to_irq(virq, cpu);
        if (irq < 0)
@@ -1181,9 +1223,6 @@ 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)
@@ -1339,10 +1378,16 @@ 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)
@@ -1504,6 +1549,18 @@ void xen_poll_irq(int irq)
        xen_poll_irq_timeout(irq, 0 /* no timeout */);
 }
 
+/* Check whether the IRQ line is shared with other guests. */
+int xen_test_irq_shared(int irq)
+{
+       struct irq_info *info = info_for_irq(irq);
+       struct physdev_irq_status_query irq_status = { .irq = info->u.pirq.pirq };
+
+       if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
+               return 0;
+       return !(irq_status.flags & XENIRQSTAT_shared);
+}
+EXPORT_SYMBOL_GPL(xen_test_irq_shared);
+
 void xen_irq_resume(void)
 {
        unsigned int cpu, evtchn;
@@ -1537,7 +1594,9 @@ 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,
 };
@@ -1547,14 +1606,15 @@ 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,