[libvirt] [PATCH v2 2/4] Added Function virNetDevGetVirtualFunctions

[Shradha Shah]

This functions enables us to get the Virtual Functions attached to
a Physical function given the name of a SR-IOV physical functio.

In order to accomplish the task, added a getter function pciGetDeviceAddrString
to get the BDF of the Virtual Function in a char array.
---
 src/util/pci.c       |   23 ++++++++++++++
 src/util/pci.h       |    5 +++
 src/util/virnetdev.c |   83 ++++++++++++++++++++++++++++++++++++++++++++++++++
 src/util/virnetdev.h |    6 +++
 4 files changed, 117 insertions(+), 0 deletions(-)

diff --git a/src/util/pci.c b/src/util/pci.c
index d0ba4c5..ca05e8f 100644
--- a/src/util/pci.c
+++ b/src/util/pci.c
@@ -1293,6 +1293,29 @@ pciReadDeviceID(pciDevice *dev, const char *id_name)
     return id_str;
 }
 
+int
+pciGetDeviceAddrString(unsigned domain,
+                       unsigned bus,
+                       unsigned slot,
+                       unsigned function,
+                       char **pciConfigAddr)
+{
+    pciDevice *dev = NULL;
+    int ret = -1;
+    
+    dev = pciGetDevice(domain, 
+                       bus, 
+                       slot, 
+                       function);
+    if (dev != NULL) {
+        *pciConfigAddr = strdup(dev->name);
+        ret = 0;
+    }
+    
+    pciFreeDevice(dev);
+    return ret;
+}
+
 pciDevice *
 pciGetDevice(unsigned domain,
              unsigned bus,
diff --git a/src/util/pci.h b/src/util/pci.h
index f98e745..b7723b1 100644
--- a/src/util/pci.h
+++ b/src/util/pci.h
@@ -111,4 +111,9 @@ int pciDeviceNetName(char *device_link_sysfs_path, char **netname);
 
 int pciSysfsFile(char *pciDeviceName, char **pci_sysfs_device_link);
 
+int pciGetDeviceAddrString(unsigned domain,
+                           unsigned bus,
+                           unsigned slot,
+                           unsigned function,
+                           char **pciConfigAddr);
 #endif /* __VIR_PCI_H__ */
diff --git a/src/util/virnetdev.c b/src/util/virnetdev.c
index fee87ef..3bbb76e 100644
--- a/src/util/virnetdev.c
+++ b/src/util/virnetdev.c
@@ -970,6 +970,78 @@ virNetDevSysfsDeviceFile(char **pf_sysfs_device_link, const char *ifname,
 }
 
 /**
+ * virNetDevGetVirtualFunctions:
+ *
+ * @pfname : name of the physical function interface name
+ * @vfname: array that will hold the interface names of the virtual_functions
+ * @n_vfname: pointer to the number of virtual functions
+ *
+ * Returns 0 on success and -1 on failure
+ */
+
+int
+virNetDevGetVirtualFunctions(const char *pfname, 
+                             char ***vfname,
+                             unsigned int *n_vfname)
+{                            
+    int ret = -1, i;
+    char *pf_sysfs_device_link = NULL;
+    char *pci_sysfs_device_link = NULL;
+    struct pci_config_address **virt_fns;
+    char *pciConfigAddr;
+    
+    if (virNetDevSysfsFile(&pf_sysfs_device_link, pfname, "device") < 0)
+        return ret;
+    
+    if (pciGetVirtualFunctions(pf_sysfs_device_link, &virt_fns,
+                               n_vfname) < 0) {
+        virReportSystemError(ENOSYS, "%s",
+                             _("Failed to get virtual functions"));
+        goto out;
+    }
+    
+    if (VIR_ALLOC_N(*vfname, *n_vfname) < 0) {
+        virReportOOMError();
+        goto out;
+    }
+    
+    for (i = 0; i < *n_vfname; i++)
+    {
+        if (pciGetDeviceAddrString(virt_fns[i]->domain, 
+                                   virt_fns[i]->bus, 
+                                   virt_fns[i]->slot, 
+                                   virt_fns[i]->function,
+                                   &pciConfigAddr) < 0) {
+            virReportSystemError(ENOSYS, "%s",
+                                 _("Failed to get PCI Config Address String"));
+            goto out;
+        }
+        if (pciSysfsFile(pciConfigAddr, &pci_sysfs_device_link) < 0) {
+            virReportSystemError(ENOSYS, "%s",
+                                 _("Failed to get PCI SYSFS file"));
+            goto out;
+        } 
+        
+        if (pciDeviceNetName(pci_sysfs_device_link, &((*vfname)[i])) < 0) {
+            virReportSystemError(ENOSYS, "%s",
+                                 _("Failed to get interface name of the VF"));
+            goto out;
+        }
+    }  
+    
+    ret = 0;
+    
+out:
+    for (i = 0; i < *n_vfname; i++)
+        VIR_FREE(virt_fns[i]);
+    VIR_FREE(virt_fns);    
+    VIR_FREE(pf_sysfs_device_link);
+    VIR_FREE(pci_sysfs_device_link);
+    VIR_FREE(pciConfigAddr);
+    return ret;
+}
+
+/**
  * virNetDevIsVirtualFunction:
  * @ifname : name of the interface
  *
@@ -1056,6 +1128,17 @@ virNetDevGetPhysicalFunction(const char *ifname, char **pfname)
     return ret;
 }
 #else /* !__linux__ */
+
+int
+virNetDevGetVirtualFunctions(const char *pfname ATTRIBUTE_UNUSED, 
+                             char ***vfname ATTRIBUTE_UNUSED,
+                             unsigned int *n_vfname ATTRIBUTE_UNUSED)
+{
+    virReportSystemError(ENOSYS, "%s",
+                         _("Unable to get virtual functions on this platfornm"));
+    return -1;
+}
+
 int
 virNetDevIsVirtualFunction(const char *ifname ATTRIBUTE_UNUSED)
 {
diff --git a/src/util/virnetdev.h b/src/util/virnetdev.h
index 13ba1da..0a885d5 100644
--- a/src/util/virnetdev.h
+++ b/src/util/virnetdev.h
@@ -99,4 +99,10 @@ int virNetDevGetVirtualFunctionIndex(const char *pfname, const char *vfname,
 int virNetDevGetPhysicalFunction(const char *ifname, char **pfname)
     ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_RETURN_CHECK;
 
+int virNetDevGetVirtualFunctions(const char *pfname, 
+                                 char ***vfname,
+                                 unsigned int *n_vfname)
+    ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2) ATTRIBUTE_NONNULL(3)
+    ATTRIBUTE_RETURN_CHECK;
+
 #endif /* __VIR_NETDEV_H__ */
-- 
1.7.4.4