x86/PCI: VMD: Synchronize with RCU freeing MSI IRQ descs

[cascardo/linux.git] / arch / x86 / pci / vmd.c

diff --git a/arch/x86/pci/vmd.c b/arch/x86/pci/vmd.c
index b814ca6..5705852 100644 (file)
--- a/arch/x86/pci/vmd.c
+++ b/arch/x86/pci/vmd.c
@@ -56,16 +56,11 @@ struct vmd_irq {
 /**
  * struct vmd_irq_list - list of driver requested IRQs mapping to a VMD vector
  * @irq_list:  the list of irq's the VMD one demuxes to.
- * @vmd_vector:        the h/w IRQ assigned to the VMD.
- * @index:     index into the VMD MSI-X table; used for message routing.
  * @count:     number of child IRQs assigned to this vector; used to track
  *             sharing.
  */
 struct vmd_irq_list {
        struct list_head        irq_list;
-       struct vmd_dev          *vmd;
-       unsigned int            vmd_vector;
-       unsigned int            index;
        unsigned int            count;
 };
 
@@ -76,7 +71,6 @@ struct vmd_dev {
        char __iomem            *cfgbar;
 
        int msix_count;
-       struct msix_entry       *msix_entries;
        struct vmd_irq_list     *irqs;
 
        struct pci_sysdata      sysdata;
@@ -95,6 +89,12 @@ static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus)
        return container_of(bus->sysdata, struct vmd_dev, sysdata);
 }
 
+static inline unsigned int index_from_irqs(struct vmd_dev *vmd,
+                                          struct vmd_irq_list *irqs)
+{
+       return irqs - vmd->irqs;
+}
+
 /*
  * Drivers managing a device in a VMD domain allocate their own IRQs as before,
  * but the MSI entry for the hardware it's driving will be programmed with a
@@ -107,9 +107,11 @@ static void vmd_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
 {
        struct vmd_irq *vmdirq = data->chip_data;
        struct vmd_irq_list *irq = vmdirq->irq;
+       struct vmd_dev *vmd = irq_data_get_irq_handler_data(data);
 
        msg->address_hi = MSI_ADDR_BASE_HI;
-       msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_DEST_ID(irq->index);
+       msg->address_lo = MSI_ADDR_BASE_LO |
+                         MSI_ADDR_DEST_ID(index_from_irqs(vmd, irq));
        msg->data = 0;
 }
 
@@ -194,6 +196,7 @@ static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
        struct msi_desc *desc = arg->desc;
        struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus);
        struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL);
+       unsigned int index, vector;
 
        if (!vmdirq)
                return -ENOMEM;
@@ -201,9 +204,11 @@ static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info,
        INIT_LIST_HEAD(&vmdirq->node);
        vmdirq->irq = vmd_next_irq(vmd, desc);
        vmdirq->virq = virq;
+       index = index_from_irqs(vmd, vmdirq->irq);
+       vector = pci_irq_vector(vmd->dev, index);
 
-       irq_domain_set_info(domain, virq, vmdirq->irq->vmd_vector, info->chip,
-                           vmdirq, handle_untracked_irq, vmd, NULL);
+       irq_domain_set_info(domain, virq, vector, info->chip, vmdirq,
+                           handle_untracked_irq, vmd, NULL);
        return 0;
 }
 
@@ -213,6 +218,8 @@ static void vmd_msi_free(struct irq_domain *domain,
        struct vmd_irq *vmdirq = irq_get_chip_data(virq);
        unsigned long flags;
 
+       synchronize_rcu();
+
        /* XXX: Potential optimization to rebalance */
        raw_spin_lock_irqsave(&list_lock, flags);
        vmdirq->irq->count--;
@@ -671,30 +678,19 @@ static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id)
        if (vmd->msix_count < 0)
                return -ENODEV;
 
+       vmd->msix_count = pci_alloc_irq_vectors(dev, 1, vmd->msix_count,
+                                       PCI_IRQ_MSIX | PCI_IRQ_AFFINITY);
+       if (vmd->msix_count < 0)
+               return vmd->msix_count;
+
        vmd->irqs = devm_kcalloc(&dev->dev, vmd->msix_count, sizeof(*vmd->irqs),
                                 GFP_KERNEL);
        if (!vmd->irqs)
                return -ENOMEM;
 
-       vmd->msix_entries = devm_kcalloc(&dev->dev, vmd->msix_count,
-                                        sizeof(*vmd->msix_entries),
-                                        GFP_KERNEL);
-       if (!vmd->msix_entries)
-               return -ENOMEM;
-       for (i = 0; i < vmd->msix_count; i++)
-               vmd->msix_entries[i].entry = i;
-
-       vmd->msix_count = pci_enable_msix_range(vmd->dev, vmd->msix_entries, 1,
-                                               vmd->msix_count);
-       if (vmd->msix_count < 0)
-               return vmd->msix_count;
-
        for (i = 0; i < vmd->msix_count; i++) {
                INIT_LIST_HEAD(&vmd->irqs[i].irq_list);
-               vmd->irqs[i].vmd_vector = vmd->msix_entries[i].vector;
-               vmd->irqs[i].index = i;
-
-               err = devm_request_irq(&dev->dev, vmd->irqs[i].vmd_vector,
+               err = devm_request_irq(&dev->dev, pci_irq_vector(dev, i),
                                       vmd_irq, 0, "vmd", &vmd->irqs[i]);
                if (err)
                        return err;