[PATCH 02/12] xen: remap MSIs into pirqs when running as initial domain

stefano.stabellini
2010-09-28T12:17:32Z

From: Qing He <qing.he@intel.com>

Implement xen_create_msi_irq to create an msi and remap it as pirq.
Use xen_create_msi_irq to implement an initial domain specific version
of setup_msi_irqs.

Signed-off-by: Qing He <qing.he@intel.com>
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
---
arch/x86/pci/xen.c | 55 +++++++++++++++++++++++++++++++---------------
drivers/xen/events.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++
include/xen/events.h | 2 +
3 files changed, 97 insertions(+), 18 deletions(-)

diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index cb8d5be..8453e36 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -229,14 +229,12 @@ static int xen_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
if (!v)
return -ENOMEM;

- if (!xen_initial_domain()) {
- if (type == PCI_CAP_ID_MSIX)
- ret = xen_pci_frontend_enable_msix(dev, &v, nvec);
- else
- ret = xen_pci_frontend_enable_msi(dev, &v);
- if (ret)
- goto error;
- }
+ if (type == PCI_CAP_ID_MSIX)
+ ret = xen_pci_frontend_enable_msix(dev, &v, nvec);
+ else
+ ret = xen_pci_frontend_enable_msi(dev, &v);
+ if (ret)
+ goto error;
i = 0;
list_for_each_entry(msidesc, &dev->msi_list, list) {
irq = xen_allocate_pirq(v[i], 0, /* not sharable */
@@ -266,23 +264,40 @@ error:

static void xen_teardown_msi_irqs(struct pci_dev *dev)
{
- /* Only do this when were are in non-privileged mode.*/
- if (!xen_initial_domain()) {
- struct msi_desc *msidesc;
-
- msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
- if (msidesc->msi_attrib.is_msix)
- xen_pci_frontend_disable_msix(dev);
- else
- xen_pci_frontend_disable_msi(dev);
- }
+ struct msi_desc *msidesc;

+ msidesc = list_entry(dev->msi_list.next, struct msi_desc, list);
+ if (msidesc->msi_attrib.is_msix)
+ xen_pci_frontend_disable_msix(dev);
+ else
+ xen_pci_frontend_disable_msi(dev);
}

static void xen_teardown_msi_irq(unsigned int irq)
{
xen_destroy_irq(irq);
}
+
+int xen_initdom_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
+{
+ int irq, ret;
+ struct msi_desc *msidesc;
+
+ list_for_each_entry(msidesc, &dev->msi_list, list) {
+ irq = xen_create_msi_irq(dev, msidesc, type);
+ if (irq < 0)
+ return -1;
+
+ ret = set_irq_msi(irq, msidesc);
+ if (ret)
+ goto error;
+ }
+ return 0;
+
+error:
+ xen_destroy_irq(irq);
+ return ret;
+}
#endif

static int xen_pcifront_enable_irq(struct pci_dev *dev)
@@ -351,6 +366,10 @@ int __init pci_xen_init(void)

static int __init pci_xen_initial_domain(void)
{
+#ifdef CONFIG_PCI_MSI
+ x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs;
+ x86_msi.teardown_msi_irq = xen_teardown_msi_irq;
+#endif
xen_setup_acpi_sci();
__acpi_register_gsi = acpi_register_gsi_xen;

diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 27e4b70..b83918a 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -29,6 +29,8 @@
#include <linux/bootmem.h>
#include <linux/slab.h>
#include <linux/irqnr.h>
+#include <linux/pci.h>
+#include <linux/msi.h>

#include <asm/desc.h>
#include <asm/ptrace.h>
@@ -49,6 +51,8 @@
#include <xen/interface/hvm/hvm_op.h>
#include <xen/interface/hvm/params.h>

+#include "../pci/msi.h"
+
/*
* This lock protects updates to the following mapping and reference-count
* arrays. The lock does not need to be acquired to read the mapping tables.
@@ -704,6 +708,60 @@ out:
return rc;
}

+int xen_create_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int type)
+{
+ int irq = 0;
+ 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);
+
+ dynamic_irq_cleanup(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;
+}
+
int xen_vector_from_irq(unsigned irq)
{
return vector_from_irq(irq);
diff --git a/include/xen/events.h b/include/xen/events.h
index 9853fce..8cd18a5 100644
--- a/include/xen/events.h
+++ b/include/xen/events.h
@@ -78,6 +78,8 @@ void xen_allocate_pirq_msi(char *name, int *irq, int *pirq);
/* De-allocates the above mentioned physical interrupt. */
int xen_destroy_irq(int irq);

+int xen_create_msi_irq(struct pci_dev *dev, struct msi_desc *msidesc, int type);
+
/* Return vector allocated to pirq */
int xen_vector_from_irq(unsigned pirq);

--
1.5.6.5