drivers/xen/xen-pciback/conf_space_capability_msi.c

   1 /*
   2  * PCI Backend -- Configuration overlay for MSI capability
   3  */
   4 #include <linux/pci.h>
   5 #include <linux/slab.h>
   6 #include "conf_space.h"
   7 #include "conf_space_capability.h"
   8 #include <xen/interface/io/pciif.h>
   9 #include <xen/events.h>
  10 #include "pciback.h"
  11
  12 int pciback_enable_msi(struct pciback_device *pdev,
  13                 struct pci_dev *dev, struct xen_pci_op *op)
  14 {
  15         struct pciback_dev_data *dev_data;
  16         int otherend = pdev->xdev->otherend_id;
  17         int status;
  18
  19         status = pci_enable_msi(dev);
  20
  21         if (status) {
  22                 printk(KERN_ERR "error enable msi for guest %x status %x\n",
  23                         otherend, status);
  24                 op->value = 0;
  25                 return XEN_PCI_ERR_op_failed;
  26         }
  27
  28         /* The value the guest needs is actually the IDT vector, not the
  29          * the local domain's IRQ number. */
  30
  31         op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
  32         dev_data = pci_get_drvdata(dev);
  33         if (dev_data)
  34                 dev_data->ack_intr = 0;
  35         return 0;
  36 }
  37
  38 int pciback_disable_msi(struct pciback_device *pdev,
  39                 struct pci_dev *dev, struct xen_pci_op *op)
  40 {
  41         struct pciback_dev_data *dev_data;
  42         pci_disable_msi(dev);
  43
  44         op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
  45         dev_data = pci_get_drvdata(dev);
  46         if (dev_data)
  47                 dev_data->ack_intr = 1;
  48         return 0;
  49 }
  50
  51 int pciback_enable_msix(struct pciback_device *pdev,
  52                 struct pci_dev *dev, struct xen_pci_op *op)
  53 {
  54         struct pciback_dev_data *dev_data;
  55         int i, result;
  56         struct msix_entry *entries;
  57
  58         if (op->value > SH_INFO_MAX_VEC)
  59                 return -EINVAL;
  60
  61         entries = kmalloc(op->value * sizeof(*entries), GFP_KERNEL);
  62         if (entries == NULL)
  63                 return -ENOMEM;
  64
  65         for (i = 0; i < op->value; i++) {
  66                 entries[i].entry = op->msix_entries[i].entry;
  67                 entries[i].vector = op->msix_entries[i].vector;
  68         }
  69
  70         result = pci_enable_msix(dev, entries, op->value);
  71
  72         if (result == 0) {
  73                 for (i = 0; i < op->value; i++) {
  74                         op->msix_entries[i].entry = entries[i].entry;
  75                         if (entries[i].vector)
  76                                 op->msix_entries[i].vector =
  77                                         xen_pirq_from_irq(entries[i].vector);
  78                 }
  79         } else {
  80                 printk(KERN_WARNING "pciback: %s: failed to enable MSI-X: err %d!\n",
  81                         pci_name(dev), result);
  82         }
  83         kfree(entries);
  84
  85         op->value = result;
  86         dev_data = pci_get_drvdata(dev);
  87         if (dev_data)
  88                 dev_data->ack_intr = 0;
  89
  90         return result;
  91 }
  92
  93 int pciback_disable_msix(struct pciback_device *pdev,
  94                 struct pci_dev *dev, struct xen_pci_op *op)
  95 {
  96         struct pciback_dev_data *dev_data;
  97
  98         pci_disable_msix(dev);
  99
 100         /*
 101          * SR-IOV devices (which don't have any legacy IRQ) have
 102          * an undefined IRQ value of zero.
 103          */
 104         op->value = dev->irq ? xen_pirq_from_irq(dev->irq) : 0;
 105         dev_data = pci_get_drvdata(dev);
 106         if (dev_data)
 107                 dev_data->ack_intr = 1;
 108
 109         return 0;
 110 }
 111