These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / xen / xen-pciback / pciback_ops.c

diff --git a/kernel/drivers/xen/xen-pciback/pciback_ops.c b/kernel/drivers/xen/xen-pciback/pciback_ops.c
index c4a0666..fb02214 100644 (file)
--- a/kernel/drivers/xen/xen-pciback/pciback_ops.c
+++ b/kernel/drivers/xen/xen-pciback/pciback_ops.c
@@ -70,6 +70,13 @@ static void xen_pcibk_control_isr(struct pci_dev *dev, int reset)
                enable ? "enable" : "disable");
 
        if (enable) {
+               /*
+                * The MSI or MSI-X should not have an IRQ handler. Otherwise
+                * if the guest terminates we BUG_ON in free_msi_irqs.
+                */
+               if (dev->msi_enabled || dev->msix_enabled)
+                       goto out;
+
                rc = request_irq(dev_data->irq,
                                xen_pcibk_guest_interrupt, IRQF_SHARED,
                                dev_data->irq_name, dev);
@@ -144,7 +151,12 @@ int xen_pcibk_enable_msi(struct xen_pcibk_device *pdev,
        if (unlikely(verbose_request))
                printk(KERN_DEBUG DRV_NAME ": %s: enable MSI\n", pci_name(dev));
 
-       status = pci_enable_msi(dev);
+       if (dev->msi_enabled)
+               status = -EALREADY;
+       else if (dev->msix_enabled)
+               status = -ENXIO;
+       else
+               status = pci_enable_msi(dev);
 
        if (status) {
                pr_warn_ratelimited("%s: error enabling MSI for guest %u: err %d\n",
@@ -173,20 +185,23 @@ static
 int xen_pcibk_disable_msi(struct xen_pcibk_device *pdev,
                          struct pci_dev *dev, struct xen_pci_op *op)
 {
-       struct xen_pcibk_dev_data *dev_data;
-
        if (unlikely(verbose_request))
                printk(KERN_DEBUG DRV_NAME ": %s: disable MSI\n",
                       pci_name(dev));
-       pci_disable_msi(dev);
 
+       if (dev->msi_enabled) {
+               struct xen_pcibk_dev_data *dev_data;
+
+               pci_disable_msi(dev);
+
+               dev_data = pci_get_drvdata(dev);
+               if (dev_data)
+                       dev_data->ack_intr = 1;
+       }
        op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
        if (unlikely(verbose_request))
                printk(KERN_DEBUG DRV_NAME ": %s: MSI: %d\n", pci_name(dev),
                        op->value);
-       dev_data = pci_get_drvdata(dev);
-       if (dev_data)
-               dev_data->ack_intr = 1;
        return 0;
 }
 
@@ -197,13 +212,27 @@ int xen_pcibk_enable_msix(struct xen_pcibk_device *pdev,
        struct xen_pcibk_dev_data *dev_data;
        int i, result;
        struct msix_entry *entries;
+       u16 cmd;
 
        if (unlikely(verbose_request))
                printk(KERN_DEBUG DRV_NAME ": %s: enable MSI-X\n",
                       pci_name(dev));
+
        if (op->value > SH_INFO_MAX_VEC)
                return -EINVAL;
 
+       if (dev->msix_enabled)
+               return -EALREADY;
+
+       /*
+        * PCI_COMMAND_MEMORY must be enabled, otherwise we may not be able
+        * to access the BARs where the MSI-X entries reside.
+        * But VF devices are unique in which the PF needs to be checked.
+        */
+       pci_read_config_word(pci_physfn(dev), PCI_COMMAND, &cmd);
+       if (dev->msi_enabled || !(cmd & PCI_COMMAND_MEMORY))
+               return -ENXIO;
+
        entries = kmalloc(op->value * sizeof(*entries), GFP_KERNEL);
        if (entries == NULL)
                return -ENOMEM;
@@ -245,23 +274,27 @@ static
 int xen_pcibk_disable_msix(struct xen_pcibk_device *pdev,
                           struct pci_dev *dev, struct xen_pci_op *op)
 {
-       struct xen_pcibk_dev_data *dev_data;
        if (unlikely(verbose_request))
                printk(KERN_DEBUG DRV_NAME ": %s: disable MSI-X\n",
                        pci_name(dev));
-       pci_disable_msix(dev);
 
+       if (dev->msix_enabled) {
+               struct xen_pcibk_dev_data *dev_data;
+
+               pci_disable_msix(dev);
+
+               dev_data = pci_get_drvdata(dev);
+               if (dev_data)
+                       dev_data->ack_intr = 1;
+       }
        /*
         * SR-IOV devices (which don't have any legacy IRQ) have
         * an undefined IRQ value of zero.
         */
        op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
        if (unlikely(verbose_request))
-               printk(KERN_DEBUG DRV_NAME ": %s: MSI-X: %d\n", pci_name(dev),
-                       op->value);
-       dev_data = pci_get_drvdata(dev);
-       if (dev_data)
-               dev_data->ack_intr = 1;
+               printk(KERN_DEBUG DRV_NAME ": %s: MSI-X: %d\n",
+                      pci_name(dev), op->value);
        return 0;
 }
 #endif
@@ -298,9 +331,14 @@ void xen_pcibk_do_op(struct work_struct *data)
                container_of(data, struct xen_pcibk_device, op_work);
        struct pci_dev *dev;
        struct xen_pcibk_dev_data *dev_data = NULL;
-       struct xen_pci_op *op = &pdev->sh_info->op;
+       struct xen_pci_op *op = &pdev->op;
        int test_intx = 0;
+#ifdef CONFIG_PCI_MSI
+       unsigned int nr = 0;
+#endif
 
+       *op = pdev->sh_info->op;
+       barrier();
        dev = xen_pcibk_get_pci_dev(pdev, op->domain, op->bus, op->devfn);
 
        if (dev == NULL)
@@ -326,6 +364,7 @@ void xen_pcibk_do_op(struct work_struct *data)
                        op->err = xen_pcibk_disable_msi(pdev, dev, op);
                        break;
                case XEN_PCI_OP_enable_msix:
+                       nr = op->value;
                        op->err = xen_pcibk_enable_msix(pdev, dev, op);
                        break;
                case XEN_PCI_OP_disable_msix:
@@ -342,6 +381,17 @@ void xen_pcibk_do_op(struct work_struct *data)
                if ((dev_data->enable_intx != test_intx))
                        xen_pcibk_control_isr(dev, 0 /* no reset */);
        }
+       pdev->sh_info->op.err = op->err;
+       pdev->sh_info->op.value = op->value;
+#ifdef CONFIG_PCI_MSI
+       if (op->cmd == XEN_PCI_OP_enable_msix && op->err == 0) {
+               unsigned int i;
+
+               for (i = 0; i < nr; i++)
+                       pdev->sh_info->op.msix_entries[i].vector =
+                               op->msix_entries[i].vector;
+       }
+#endif
        /* Tell the driver domain that we're done. */
        wmb();
        clear_bit(_XEN_PCIF_active, (unsigned long *)&pdev->sh_info->flags);