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-rw-r--r--drivers/xen/events.c509
1 files changed, 488 insertions, 21 deletions
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 347f17e..97612f5 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -16,7 +16,7 @@
* (typically dom0).
* 2. VIRQs, typically used for timers. These are per-cpu events.
* 3. IPIs.
- * 4. Hardware interrupts. Not supported at present.
+ * 4. PIRQs - Hardware interrupts.
*
* Jeremy Fitzhardinge <jeremy@xensource.com>, XenSource Inc, 2007
*/
@@ -28,12 +28,16 @@
#include <linux/string.h>
#include <linux/bootmem.h>
#include <linux/slab.h>
+#include <linux/irqnr.h>
+#include <linux/pci.h>
#include <asm/desc.h>
#include <asm/ptrace.h>
#include <asm/irq.h>
#include <asm/idle.h>
+#include <asm/io_apic.h>
#include <asm/sync_bitops.h>
+#include <asm/xen/pci.h>
#include <asm/xen/hypercall.h>
#include <asm/xen/hypervisor.h>
@@ -73,7 +77,8 @@ enum xen_irq_type {
* event channel - irq->event channel mapping
* cpu - cpu this event channel is bound to
* index - type-specific information:
- * PIRQ - vector, with MSB being "needs EIO"
+ * PIRQ - vector, with MSB being "needs EIO", or physical IRQ of the HVM
+ * guest, or GSI (real passthrough IRQ) of the device.
* VIRQ - virq number
* IPI - IPI vector
* EVTCHN -
@@ -88,21 +93,30 @@ struct irq_info
unsigned short virq;
enum ipi_vector ipi;
struct {
+ unsigned short pirq;
unsigned short gsi;
- unsigned short vector;
+ unsigned char vector;
+ unsigned char flags;
} pirq;
} u;
};
+#define PIRQ_NEEDS_EOI (1 << 0)
+#define PIRQ_SHAREABLE (1 << 1)
-static struct irq_info irq_info[NR_IRQS];
+static struct irq_info *irq_info;
+static int *pirq_to_irq;
+static int nr_pirqs;
-static int evtchn_to_irq[NR_EVENT_CHANNELS] = {
- [0 ... NR_EVENT_CHANNELS-1] = -1
-};
+static int *evtchn_to_irq;
struct cpu_evtchn_s {
unsigned long bits[NR_EVENT_CHANNELS/BITS_PER_LONG];
};
-static struct cpu_evtchn_s *cpu_evtchn_mask_p;
+
+static __initdata struct cpu_evtchn_s init_evtchn_mask = {
+ .bits[0 ... (NR_EVENT_CHANNELS/BITS_PER_LONG)-1] = ~0ul,
+};
+static struct cpu_evtchn_s *cpu_evtchn_mask_p = &init_evtchn_mask;
+
static inline unsigned long *cpu_evtchn_mask(int cpu)
{
return cpu_evtchn_mask_p[cpu].bits;
@@ -113,6 +127,7 @@ static inline unsigned long *cpu_evtchn_mask(int cpu)
static struct irq_chip xen_dynamic_chip;
static struct irq_chip xen_percpu_chip;
+static struct irq_chip xen_pirq_chip;
/* Constructor for packed IRQ information. */
static struct irq_info mk_unbound_info(void)
@@ -138,11 +153,12 @@ static struct irq_info mk_virq_info(unsigned short evtchn, unsigned short virq)
.cpu = 0, .u.virq = virq };
}
-static struct irq_info mk_pirq_info(unsigned short evtchn,
+static struct irq_info mk_pirq_info(unsigned short evtchn, unsigned short pirq,
unsigned short gsi, unsigned short vector)
{
return (struct irq_info) { .type = IRQT_PIRQ, .evtchn = evtchn,
- .cpu = 0, .u.pirq = { .gsi = gsi, .vector = vector } };
+ .cpu = 0,
+ .u.pirq = { .pirq = pirq, .gsi = gsi, .vector = vector } };
}
/*
@@ -184,6 +200,16 @@ static unsigned virq_from_irq(unsigned irq)
return info->u.virq;
}
+static unsigned pirq_from_irq(unsigned irq)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ BUG_ON(info == NULL);
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ return info->u.pirq.pirq;
+}
+
static unsigned gsi_from_irq(unsigned irq)
{
struct irq_info *info = info_for_irq(irq);
@@ -225,6 +251,15 @@ static unsigned int cpu_from_evtchn(unsigned int evtchn)
return ret;
}
+static bool pirq_needs_eoi(unsigned irq)
+{
+ struct irq_info *info = info_for_irq(irq);
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ return info->u.pirq.flags & PIRQ_NEEDS_EOI;
+}
+
static inline unsigned long active_evtchns(unsigned int cpu,
struct shared_info *sh,
unsigned int idx)
@@ -336,12 +371,40 @@ static void unmask_evtchn(int port)
put_cpu();
}
+static int get_nr_hw_irqs(void)
+{
+ int ret = 1;
+
+#ifdef CONFIG_X86_IO_APIC
+ ret = get_nr_irqs_gsi();
+#endif
+
+ 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)
+{
+ int i;
+ for (i = nr_pirqs-1; i >= 0; i--) {
+ if (pirq_to_irq[i] < 0)
+ return i;
+ }
+ return -1;
+}
+
static int find_unbound_irq(void)
{
struct irq_data *data;
int irq, res;
+ int start = get_nr_hw_irqs();
- for (irq = 0; irq < nr_irqs; irq++) {
+ if (start == nr_irqs)
+ goto no_irqs;
+
+ /* nr_irqs is a magic value. Must not use it.*/
+ for (irq = nr_irqs-1; irq > start; irq--) {
data = irq_get_irq_data(irq);
/* only 0->15 have init'd desc; handle irq > 16 */
if (!data)
@@ -354,8 +417,8 @@ static int find_unbound_irq(void)
return irq;
}
- if (irq == nr_irqs)
- panic("No available IRQ to bind to: increase nr_irqs!\n");
+ if (irq == start)
+ goto no_irqs;
res = irq_alloc_desc_at(irq, 0);
@@ -363,6 +426,357 @@ static int find_unbound_irq(void)
return -1;
return irq;
+
+no_irqs:
+ panic("No available IRQ to bind to: increase nr_irqs!\n");
+}
+
+static bool identity_mapped_irq(unsigned irq)
+{
+ /* identity map all the hardware irqs */
+ return irq < get_nr_hw_irqs();
+}
+
+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;
+ struct irq_info *info = info_for_irq(irq);
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ irq_status.irq = pirq_from_irq(irq);
+ if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))
+ irq_status.flags = 0;
+
+ info->u.pirq.flags &= ~PIRQ_NEEDS_EOI;
+ if (irq_status.flags & XENIRQSTAT_needs_eoi)
+ info->u.pirq.flags |= PIRQ_NEEDS_EOI;
+}
+
+static bool probing_irq(int irq)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+
+ return desc && desc->action == NULL;
+}
+
+static unsigned int startup_pirq(unsigned int irq)
+{
+ struct evtchn_bind_pirq bind_pirq;
+ struct irq_info *info = info_for_irq(irq);
+ int evtchn = evtchn_from_irq(irq);
+ int rc;
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ if (VALID_EVTCHN(evtchn))
+ goto out;
+
+ bind_pirq.pirq = pirq_from_irq(irq);
+ /* NB. We are happy to share unless we are probing. */
+ bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ?
+ BIND_PIRQ__WILL_SHARE : 0;
+ rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq);
+ if (rc != 0) {
+ if (!probing_irq(irq))
+ printk(KERN_INFO "Failed to obtain physical IRQ %d\n",
+ irq);
+ return 0;
+ }
+ evtchn = bind_pirq.port;
+
+ pirq_query_unmask(irq);
+
+ evtchn_to_irq[evtchn] = irq;
+ bind_evtchn_to_cpu(evtchn, 0);
+ info->evtchn = evtchn;
+
+out:
+ unmask_evtchn(evtchn);
+ pirq_unmask_notify(irq);
+
+ return 0;
+}
+
+static void shutdown_pirq(unsigned int irq)
+{
+ struct evtchn_close close;
+ struct irq_info *info = info_for_irq(irq);
+ int evtchn = evtchn_from_irq(irq);
+
+ BUG_ON(info->type != IRQT_PIRQ);
+
+ if (!VALID_EVTCHN(evtchn))
+ return;
+
+ mask_evtchn(evtchn);
+
+ close.port = evtchn;
+ if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
+ BUG();
+
+ bind_evtchn_to_cpu(evtchn, 0);
+ evtchn_to_irq[evtchn] = -1;
+ info->evtchn = 0;
+}
+
+static void enable_pirq(unsigned int irq)
+{
+ startup_pirq(irq);
+}
+
+static void disable_pirq(unsigned int irq)
+{
+}
+
+static void ack_pirq(unsigned int irq)
+{
+ int evtchn = evtchn_from_irq(irq);
+
+ move_native_irq(irq);
+
+ if (VALID_EVTCHN(evtchn)) {
+ mask_evtchn(evtchn);
+ clear_evtchn(evtchn);
+ }
+}
+
+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;
+
+ for (irq = 0; irq < nr_irqs; irq++) {
+ struct irq_info *info = info_for_irq(irq);
+
+ if (info == NULL || info->type != IRQT_PIRQ)
+ continue;
+
+ if (gsi_from_irq(irq) == gsi)
+ return irq;
+ }
+
+ return -1;
+}
+
+int xen_allocate_pirq(unsigned gsi, int shareable, char *name)
+{
+ return xen_map_pirq_gsi(gsi, gsi, shareable, name);
+}
+
+/* xen_map_pirq_gsi might allocate irqs from the top down, as a
+ * consequence don't assume that the irq number returned has a low value
+ * or can be used as a pirq number unless you know otherwise.
+ *
+ * One notable exception is when xen_map_pirq_gsi is called passing an
+ * hardware gsi as argument, in that case the irq number returned
+ * matches the gsi number passed as second argument.
+ *
+ * Note: We don't assign an event channel until the irq actually started
+ * up. Return an existing irq if we've already got one for the gsi.
+ */
+int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name)
+{
+ int irq = 0;
+ struct physdev_irq irq_op;
+
+ spin_lock(&irq_mapping_update_lock);
+
+ if ((pirq > nr_pirqs) || (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" : "");
+ goto out;
+ }
+
+ irq = find_irq_by_gsi(gsi);
+ if (irq != -1) {
+ printk(KERN_INFO "xen_map_pirq_gsi: returning irq %d for gsi %u\n",
+ irq, gsi);
+ 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, 0);
+ } else
+ irq = find_unbound_irq();
+
+ set_irq_chip_and_handler_name(irq, &xen_pirq_chip,
+ handle_level_irq, name);
+
+ irq_op.irq = irq;
+ irq_op.vector = 0;
+
+ /* Only the privileged domain can do this. For non-priv, the pcifront
+ * driver provides a PCI bus that does the call to do exactly
+ * this in the priv domain. */
+ if (xen_initial_domain() &&
+ HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op)) {
+ irq_free_desc(irq);
+ irq = -ENOSPC;
+ goto out;
+ }
+
+ irq_info[irq] = mk_pirq_info(0, pirq, gsi, irq_op.vector);
+ irq_info[irq].u.pirq.flags |= shareable ? PIRQ_SHAREABLE : 0;
+ pirq_to_irq[pirq] = irq;
+
+out:
+ spin_unlock(&irq_mapping_update_lock);
+
+ return irq;
+}
+
+#ifdef CONFIG_PCI_MSI
+#include <linux/msi.h>
+#include "../pci/msi.h"
+
+void xen_allocate_pirq_msi(char *name, int *irq, int *pirq)
+{
+ spin_lock(&irq_mapping_update_lock);
+
+ *irq = find_unbound_irq();
+ if (*irq == -1)
+ goto out;
+
+ *pirq = find_unbound_pirq();
+ if (*pirq == -1)
+ goto out;
+
+ set_irq_chip_and_handler_name(*irq, &xen_pirq_chip,
+ handle_level_irq, name);
+
+ irq_info[*irq] = mk_pirq_info(0, *pirq, 0, 0);
+ pirq_to_irq[*pirq] = *irq;
+
+out:
+ spin_unlock(&irq_mapping_update_lock);
+}
+
+int xen_create_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int type)
+{
+ int irq = -1;
+ struct physdev_map_pirq map_irq;
+ int rc;
+ int pos;
+ u32 table_offset, bir;
+
+ memset(&map_irq, 0, sizeof(map_irq));
+ map_irq.domid = DOMID_SELF;
+ map_irq.type = MAP_PIRQ_TYPE_MSI;
+ map_irq.index = -1;
+ map_irq.pirq = -1;
+ map_irq.bus = dev->bus->number;
+ map_irq.devfn = dev->devfn;
+
+ if (type == PCI_CAP_ID_MSIX) {
+ pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
+
+ pci_read_config_dword(dev, msix_table_offset_reg(pos),
+ &table_offset);
+ bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
+
+ map_irq.table_base = pci_resource_start(dev, bir);
+ map_irq.entry_nr = msidesc->msi_attrib.entry_nr;
+ }
+
+ spin_lock(&irq_mapping_update_lock);
+
+ irq = find_unbound_irq();
+
+ if (irq == -1)
+ goto out;
+
+ rc = HYPERVISOR_physdev_op(PHYSDEVOP_map_pirq, &map_irq);
+ if (rc) {
+ printk(KERN_WARNING "xen map irq failed %d\n", rc);
+
+ irq_free_desc(irq);
+
+ irq = -1;
+ goto out;
+ }
+ irq_info[irq] = mk_pirq_info(0, map_irq.pirq, 0, map_irq.index);
+
+ set_irq_chip_and_handler_name(irq, &xen_pirq_chip,
+ handle_level_irq,
+ (type == PCI_CAP_ID_MSIX) ? "msi-x":"msi");
+
+out:
+ spin_unlock(&irq_mapping_update_lock);
+ return irq;
+}
+#endif
+
+int xen_destroy_irq(int irq)
+{
+ struct irq_desc *desc;
+ struct physdev_unmap_pirq unmap_irq;
+ struct irq_info *info = info_for_irq(irq);
+ int rc = -ENOENT;
+
+ spin_lock(&irq_mapping_update_lock);
+
+ desc = irq_to_desc(irq);
+ if (!desc)
+ goto out;
+
+ if (xen_initial_domain()) {
+ unmap_irq.pirq = info->u.pirq.gsi;
+ unmap_irq.domid = DOMID_SELF;
+ rc = HYPERVISOR_physdev_op(PHYSDEVOP_unmap_pirq, &unmap_irq);
+ if (rc) {
+ printk(KERN_WARNING "unmap irq failed %d\n", rc);
+ goto out;
+ }
+ }
+ irq_info[irq] = mk_unbound_info();
+
+ irq_free_desc(irq);
+
+out:
+ spin_unlock(&irq_mapping_update_lock);
+ return rc;
+}
+
+int xen_vector_from_irq(unsigned irq)
+{
+ return vector_from_irq(irq);
+}
+
+int xen_gsi_from_irq(unsigned irq)
+{
+ return gsi_from_irq(irq);
}
int bind_evtchn_to_irq(unsigned int evtchn)
@@ -425,7 +839,7 @@ static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
}
-static int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
+int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
{
struct evtchn_bind_virq bind_virq;
int evtchn, irq;
@@ -928,7 +1342,7 @@ void xen_clear_irq_pending(int irq)
if (VALID_EVTCHN(evtchn))
clear_evtchn(evtchn);
}
-
+EXPORT_SYMBOL(xen_clear_irq_pending);
void xen_set_irq_pending(int irq)
{
int evtchn = evtchn_from_irq(irq);
@@ -948,9 +1362,9 @@ bool xen_test_irq_pending(int irq)
return ret;
}
-/* Poll waiting for an irq to become pending. In the usual case, the
- irq will be disabled so it won't deliver an interrupt. */
-void xen_poll_irq(int irq)
+/* Poll waiting for an irq to become pending with timeout. In the usual case,
+ * the irq will be disabled so it won't deliver an interrupt. */
+void xen_poll_irq_timeout(int irq, u64 timeout)
{
evtchn_port_t evtchn = evtchn_from_irq(irq);
@@ -958,13 +1372,20 @@ void xen_poll_irq(int irq)
struct sched_poll poll;
poll.nr_ports = 1;
- poll.timeout = 0;
+ poll.timeout = timeout;
set_xen_guest_handle(poll.ports, &evtchn);
if (HYPERVISOR_sched_op(SCHEDOP_poll, &poll) != 0)
BUG();
}
}
+EXPORT_SYMBOL(xen_poll_irq_timeout);
+/* Poll waiting for an irq to become pending. In the usual case, the
+ * irq will be disabled so it won't deliver an interrupt. */
+void xen_poll_irq(int irq)
+{
+ xen_poll_irq_timeout(irq, 0 /* no timeout */);
+}
void xen_irq_resume(void)
{
@@ -1001,6 +1422,26 @@ static struct irq_chip xen_dynamic_chip __read_mostly = {
.retrigger = retrigger_dynirq,
};
+static struct irq_chip xen_pirq_chip __read_mostly = {
+ .name = "xen-pirq",
+
+ .startup = startup_pirq,
+ .shutdown = shutdown_pirq,
+
+ .enable = enable_pirq,
+ .unmask = enable_pirq,
+
+ .disable = disable_pirq,
+ .mask = disable_pirq,
+
+ .ack = ack_pirq,
+ .end = end_pirq,
+
+ .set_affinity = set_affinity_irq,
+
+ .retrigger = retrigger_dynirq,
+};
+
static struct irq_chip xen_percpu_chip __read_mostly = {
.name = "xen-percpu",
@@ -1051,11 +1492,32 @@ void xen_callback_vector(void) {}
void __init xen_init_IRQ(void)
{
- int i;
+ int i, rc;
+ struct physdev_nr_pirqs op_nr_pirqs;
cpu_evtchn_mask_p = kcalloc(nr_cpu_ids, sizeof(struct cpu_evtchn_s),
GFP_KERNEL);
- BUG_ON(cpu_evtchn_mask_p == NULL);
+ 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++)
+ pirq_to_irq[i] = -1;
+
+ evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq),
+ GFP_KERNEL);
+ for (i = 0; i < NR_EVENT_CHANNELS; i++)
+ evtchn_to_irq[i] = -1;
init_evtchn_cpu_bindings();
@@ -1066,7 +1528,12 @@ void __init xen_init_IRQ(void)
if (xen_hvm_domain()) {
xen_callback_vector();
native_init_IRQ();
+ /* pci_xen_hvm_init must be called after native_init_IRQ so that
+ * __acpi_register_gsi can point at the right function */
+ pci_xen_hvm_init();
} else {
irq_ctx_init(smp_processor_id());
+ if (xen_initial_domain())
+ xen_setup_pirqs();
}
}
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