[PATCH 09/16] kvm: expose MSI capability to guest

Sheng Yang
2009-03-12T13:37:06Z

(Alex: correct libpci usage)

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
---
qemu/hw/device-assignment.c | 140 ++++++++++++++++++++++++++++++++++++++++--
qemu/hw/device-assignment.h | 9 +++
2 files changed, 142 insertions(+), 7 deletions(-)

diff --git a/qemu/hw/device-assignment.c b/qemu/hw/device-assignment.c
index a354681..bda0e95 100644
--- a/qemu/hw/device-assignment.c
+++ b/qemu/hw/device-assignment.c
@@ -265,7 +265,8 @@ static void assigned_dev_pci_write_config(PCIDevice *d, uint32_t address,
}

if ((address >= 0x10 && address <= 0x24) || address == 0x34 ||
- address == 0x3c || address == 0x3d) {
+ address == 0x3c || address == 0x3d ||
+ pci_access_cap_config(d, address, len)) {
/* used for update-mappings (BAR emulation) */
pci_default_write_config(d, address, val, len);
return;
@@ -299,7 +300,8 @@ static uint32_t assigned_dev_pci_read_config(PCIDevice *d, uint32_t address,
AssignedDevice *pci_dev = container_of(d, AssignedDevice, dev);

if ((address >= 0x10 && address <= 0x24) || address == 0x34 ||
- address == 0x3c || address == 0x3d) {
+ address == 0x3c || address == 0x3d ||
+ pci_access_cap_config(d, address, len)) {
val = pci_default_read_config(d, address, len);
DEBUG("(%x.%x): address=%04x val=0x%08x len=%d\n",
(d->devfn >> 3) & 0x1F, (d->devfn & 0x7), address, val, len);
@@ -328,11 +330,13 @@ do_log:
DEBUG("(%x.%x): address=%04x val=0x%08x len=%d\n",
(d->devfn >> 3) & 0x1F, (d->devfn & 0x7), address, val, len);

- /* kill the special capabilities */
- if (address == 4 && len == 4)
- val &= ~0x100000;
- else if (address == 6)
- val &= ~0x10;
+ if (!pci_dev->cap.available) {
+ /* kill the special capabilities */
+ if (address == 4 && len == 4)
+ val &= ~0x100000;
+ else if (address == 6)
+ val &= ~0x10;
+ }

return val;
}
@@ -474,6 +478,19 @@ again:

static LIST_HEAD(, AssignedDevInfo) adev_head;

+#ifdef KVM_CAP_IRQ_ROUTING
+static void free_dev_irq_entries(AssignedDevice *dev)
+{
+ int i;
+
+ for (i = 0; i < dev->irq_entries_nr; i++)
+ kvm_del_routing_entry(kvm_context, &dev->entry[i]);
+ free(dev->entry);
+ dev->entry = NULL;
+ dev->irq_entries_nr = 0;
+}
+#endif
+
static void free_assigned_device(AssignedDevInfo *adev)
{
AssignedDevice *dev = adev->assigned_dev;
@@ -506,6 +523,9 @@ static void free_assigned_device(AssignedDevInfo *adev)
}

pci_unregister_device(&dev->dev);
+#ifdef KVM_CAP_IRQ_ROUTING
+ free_dev_irq_entries(dev);
+#endif
adev->assigned_dev = dev = NULL;
}

@@ -645,11 +665,108 @@ void assigned_dev_update_irqs()
}
}

+#if defined(KVM_CAP_DEVICE_MSI) && defined (KVM_CAP_IRQ_ROUTING)
+static void assigned_dev_update_msi(PCIDevice *pci_dev, unsigned int ctrl_pos)
+{
+ struct kvm_assigned_irq assigned_irq_data;
+ AssignedDevice *assigned_dev = container_of(pci_dev, AssignedDevice, dev);
+ uint8_t ctrl_byte = pci_dev->config[ctrl_pos];
+ int r;
+
+ memset(&assigned_irq_data, 0, sizeof assigned_irq_data);
+ assigned_irq_data.assigned_dev_id =
+ calc_assigned_dev_id(assigned_dev->h_busnr,
+ (uint8_t)assigned_dev->h_devfn);
+
+ assigned_irq_data.flags = KVM_DEV_IRQ_HOST_MSI | KVM_DEV_IRQ_GUEST_MSI;
+
+ free_dev_irq_entries(assigned_dev);
+ r = kvm_deassign_irq(kvm_context, &assigned_irq_data);
+ /* -ENXIO means no assigned irq */
+ if (r && r != -ENXIO)
+ perror("assigned_dev_update_msi: deassign irq");
+
+ if (ctrl_byte & PCI_MSI_FLAGS_ENABLE) {
+ assigned_dev->entry = calloc(1, sizeof(struct kvm_irq_routing_entry));
+ if (!assigned_dev->entry) {
+ perror("assigned_dev_update_msi: ");
+ return;
+ }
+ assigned_dev->entry->u.msi.address_lo =
+ *(uint32_t *)(pci_dev->config + pci_dev->cap.start +
+ PCI_MSI_ADDRESS_LO);
+ assigned_dev->entry->u.msi.address_hi = 0;
+ assigned_dev->entry->u.msi.data = *(uint16_t *)(pci_dev->config +
+ pci_dev->cap.start + PCI_MSI_DATA_32);
+ assigned_dev->entry->type = KVM_IRQ_ROUTING_MSI;
+ assigned_dev->entry->gsi = kvm_get_irq_route_gsi(kvm_context);
+ if (assigned_dev->entry->gsi < 0) {
+ perror("assigned_dev_update_msi: kvm_get_irq_route_gsi");
+ return;
+ }
+
+ kvm_add_routing_entry(kvm_context, assigned_dev->entry);
+ if (kvm_commit_irq_routes(kvm_context) < 0) {
+ perror("assigned_dev_update_msi: kvm_commit_irq_routes");
+ assigned_dev->cap.state &= ~ASSIGNED_DEVICE_MSI_ENABLED;
+ return;
+ }
+ assigned_irq_data.guest_irq = assigned_dev->entry->gsi;
+ }
+
+ if (ctrl_byte & PCI_MSI_FLAGS_ENABLE)
+ if (kvm_assign_irq(kvm_context, &assigned_irq_data) < 0)
+ perror("assigned_dev_enable_msi: assign irq");
+}
+#endif
+
+static void assigned_device_pci_cap_write_config(PCIDevice *pci_dev, uint32_t address,
+ uint32_t val, int len)
+{
+ AssignedDevice *assigned_dev = container_of(pci_dev, AssignedDevice, dev);
+ unsigned int pos = pci_dev->cap.start, ctrl_pos;
+
+ pci_default_cap_write_config(pci_dev, address, val, len);
+#if defined(KVM_CAP_DEVICE_MSI) && defined (KVM_CAP_IRQ_ROUTING)
+ if (assigned_dev->cap.available & ASSIGNED_DEVICE_CAP_MSI) {
+ ctrl_pos = pos + PCI_MSI_FLAGS;
+ if (address <= ctrl_pos && address + len > ctrl_pos)
+ assigned_dev_update_msi(pci_dev, ctrl_pos);
+ pos += PCI_CAPABILITY_CONFIG_MSI_LENGTH;
+ }
+#endif
+ return;
+}
+
+static int assigned_device_pci_cap_init(PCIDevice *pci_dev)
+{
+ AssignedDevice *dev = container_of(pci_dev, AssignedDevice, dev);
+ int next_cap_pt = 0;
+
+ pci_dev->cap.length = 0;
+#if defined(KVM_CAP_DEVICE_MSI) && defined (KVM_CAP_IRQ_ROUTING)
+ /* Expose MSI capability
+ * MSI capability is the 1st capability in capability config */
+ if (pci_find_cap_offset(dev->pdev, PCI_CAP_ID_MSI)) {
+ dev->cap.available |= ASSIGNED_DEVICE_CAP_MSI;
+ memset(&pci_dev->config[pci_dev->cap.start + pci_dev->cap.length],
+ 0, PCI_CAPABILITY_CONFIG_MSI_LENGTH);
+ pci_dev->config[pci_dev->cap.start + pci_dev->cap.length] =
+ PCI_CAP_ID_MSI;
+ pci_dev->cap.length += PCI_CAPABILITY_CONFIG_MSI_LENGTH;
+ next_cap_pt = 1;
+ }
+#endif
+
+ return 0;
+}
+
struct PCIDevice *init_assigned_device(AssignedDevInfo *adev, PCIBus *bus)
{
int r;
AssignedDevice *dev;
PCIDevice *pci_dev;
+ struct pci_access *pacc;
uint8_t e_device, e_intx;

DEBUG("Registering real physical device %s (bus=%x dev=%x func=%x)\n",
@@ -689,6 +806,10 @@ struct PCIDevice *init_assigned_device(AssignedDevInfo *adev, PCIBus *bus)
dev->h_busnr = adev->bus;
dev->h_devfn = PCI_DEVFN(adev->dev, adev->func);

+ pacc = pci_alloc();
+ pci_init(pacc);
+ dev->pdev = pci_get_dev(pacc, 0, adev->bus, adev->dev, adev->func);
+
/* assign device to guest */
r = assign_device(adev);
if (r < 0)
@@ -699,6 +820,11 @@ struct PCIDevice *init_assigned_device(AssignedDevInfo *adev, PCIBus *bus)
if (r < 0)
goto assigned_out;

+ if (pci_enable_capability_support(pci_dev, 0, NULL,
+ assigned_device_pci_cap_write_config,
+ assigned_device_pci_cap_init) < 0)
+ goto assigned_out;
+
return &dev->dev;

assigned_out:
diff --git a/qemu/hw/device-assignment.h b/qemu/hw/device-assignment.h
index 0fd78de..b1f2156 100644
--- a/qemu/hw/device-assignment.h
+++ b/qemu/hw/device-assignment.h
@@ -81,6 +81,15 @@ typedef struct {
unsigned char h_busnr;
unsigned int h_devfn;
int bound;
+ struct pci_dev *pdev;
+ struct {
+#define ASSIGNED_DEVICE_CAP_MSI (1 << 0)
+ uint32_t available;
+#define ASSIGNED_DEVICE_MSI_ENABLED (1 << 0)
+ uint32_t state;
+ } cap;
+ int irq_entries_nr;
+ struct kvm_irq_routing_entry *entry;
} AssignedDevice;

typedef struct AssignedDevInfo AssignedDevInfo;
--
1.5.4.5