virtio: fix device specific header offset when MSI-X is disabled

[dpdk.git] / lib / librte_pmd_virtio / virtio_ethdev.c

diff --git a/lib/librte_pmd_virtio/virtio_ethdev.c b/lib/librte_pmd_virtio/virtio_ethdev.c
index d4730f9..afc903c 100644 (file)
--- a/lib/librte_pmd_virtio/virtio_ethdev.c
+++ b/lib/librte_pmd_virtio/virtio_ethdev.c
@@ -647,6 +647,30 @@ static int get_uio_dev(struct rte_pci_addr *loc, char *buf, unsigned int buflen)
 
        return 0;
 }
+
+static int
+virtio_has_msix(const struct rte_pci_addr *loc)
+{
+       DIR *d;
+       char dirname[PATH_MAX];
+
+       snprintf(dirname, sizeof(dirname),
+                    SYSFS_PCI_DEVICES "/" PCI_PRI_FMT "/msi_irqs",
+                    loc->domain, loc->bus, loc->devid, loc->function);
+
+       d = opendir(dirname);
+       if (d)
+               closedir(d);
+
+       return (d != NULL);
+}
+#else
+static int
+virtio_has_msix(const struct rte_pci_addr *loc __rte_unused)
+{
+       /* nic_uio does not enable interrupts, return 0 (false). */
+       return 0;
+}
 #endif
 
 /*
@@ -720,6 +744,7 @@ eth_virtio_dev_init(__rte_unused struct eth_driver *eth_drv,
                             start, size);
        }
 #endif
+       hw->use_msix = virtio_has_msix(&pci_dev->addr);
        hw->io_base = (uint32_t)(uintptr_t)pci_dev->mem_resource[0].addr;
 
        /* Reset the device although not necessary at startup */