nodedev: Introduce virNodeDeviceCapsListExport

Whether asking for a number of capabilities supported by a device or
listing them, it's handled essentially by a copy-paste code, so extract
the common stuff into this new helper which also updates all
capabilities just before touching them.

Signed-off-by: Erik Skultety <eskultet@redhat.com>

src/conf/node_device_conf.c

@@ -2487,6 +2487,79 @@ virNodeDeviceUpdateCaps(virNodeDeviceDefPtr def)
 }
 
 
+/**
+ * virNodeDeviceCapsListExport:
+ * @def: node device definition
+ * @list: pointer to an array to store all supported capabilities by a device
+ *
+ * Takes the definition, scans through all the capabilities that the device
+ * supports (including the nested caps) and populates a newly allocated list
+ * with them. Caller is responsible for freeing the list.
+ * If NULL is passed to @list, only the number of caps will be returned.
+ *
+ * Returns the number of capabilities the device supports, -1 on error.
+ */
+int
+virNodeDeviceCapsListExport(virNodeDeviceDefPtr def,
+                            virNodeDevCapType **list)
+{
+    virNodeDevCapsDefPtr caps = NULL;
+    virNodeDevCapType *tmp = NULL;
+    bool want_list = !!list;
+    int ncaps = 0;
+    int ret = -1;
+
+#define MAYBE_ADD_CAP(cap) \
+    do { \
+        if (want_list) \
+            tmp[ncaps] = cap; \
+    } while (0)
+
+    if (want_list && VIR_ALLOC_N(tmp, VIR_NODE_DEV_CAP_LAST - 1) < 0)
+        goto cleanup;
+
+    for (caps = def->caps; caps; caps = caps->next) {
+        unsigned int flags;
+
+        MAYBE_ADD_CAP(caps->data.type);
+        ncaps++;
+
+        /* check nested caps for a given type as well */
+        if (caps->data.type == VIR_NODE_DEV_CAP_SCSI_HOST) {
+            flags = caps->data.scsi_host.flags;
+
+            if (flags & VIR_NODE_DEV_CAP_FLAG_HBA_FC_HOST) {
+                MAYBE_ADD_CAP(VIR_NODE_DEV_CAP_FC_HOST);
+                ncaps++;
+            }
+
+            if (flags  & VIR_NODE_DEV_CAP_FLAG_HBA_VPORT_OPS) {
+                MAYBE_ADD_CAP(VIR_NODE_DEV_CAP_VPORTS);
+                ncaps++;
+            }
+        }
+
+        if (caps->data.type == VIR_NODE_DEV_CAP_PCI_DEV) {
+            flags = caps->data.pci_dev.flags;
+
+            if (flags & VIR_NODE_DEV_CAP_FLAG_PCI_MDEV) {
+                MAYBE_ADD_CAP(VIR_NODE_DEV_CAP_MDEV_TYPES);
+                ncaps++;
+            }
+        }
+    }
+
+#undef MAYBE_ADD_CAP
+
+    if (want_list)
+        VIR_STEAL_PTR(*list, tmp);
+    ret = ncaps;
+ cleanup:
+    VIR_FREE(tmp);
+    return ret;
+}
+
+
 #ifdef __linux__
 
 int

src/conf/node_device_conf.h

@@ -403,4 +403,9 @@ virNodeDeviceGetPCIDynamicCaps(const char *sysfsPath,
 
 int
 virNodeDeviceUpdateCaps(virNodeDeviceDefPtr def);
+
+int
+virNodeDeviceCapsListExport(virNodeDeviceDefPtr def,
+                            virNodeDevCapType **list);
+
 #endif /* __VIR_NODE_DEVICE_CONF_H__ */

src/libvirt_private.syms

@@ -699,6 +699,7 @@ virNodeDevCapMdevTypeFree;
 virNodeDevCapsDefFree;
 virNodeDevCapTypeFromString;
 virNodeDevCapTypeToString;
+virNodeDeviceCapsListExport;
 virNodeDeviceCreateVport;
 virNodeDeviceDefFormat;
 virNodeDeviceDefFree;

src/node_device/node_device_driver.c

@@ -306,8 +306,6 @@ nodeDeviceNumOfCaps(virNodeDevicePtr device)
 {
     virNodeDeviceObjPtr obj;
     virNodeDeviceDefPtr def;
-    virNodeDevCapsDefPtr caps;
-    int ncaps = 0;
     int ret = -1;
 
     if (!(obj = nodeDeviceObjFindByName(device->name)))
@@ -317,27 +315,7 @@ nodeDeviceNumOfCaps(virNodeDevicePtr device)
     if (virNodeDeviceNumOfCapsEnsureACL(device->conn, def) < 0)
         goto cleanup;
 
-    for (caps = def->caps; caps; caps = caps->next) {
+    ret = virNodeDeviceCapsListExport(def, NULL);
-        ++ncaps;
-
-        if (caps->data.type == VIR_NODE_DEV_CAP_SCSI_HOST) {
-            if (caps->data.scsi_host.flags &
-                VIR_NODE_DEV_CAP_FLAG_HBA_FC_HOST)
-                ncaps++;
-
-            if (caps->data.scsi_host.flags &
-                VIR_NODE_DEV_CAP_FLAG_HBA_VPORT_OPS)
-                ncaps++;
-        }
-        if (caps->data.type == VIR_NODE_DEV_CAP_PCI_DEV) {
-            if (caps->data.pci_dev.flags &
-                VIR_NODE_DEV_CAP_FLAG_PCI_MDEV)
-                ncaps++;
-        }
-
-    }
-
-    ret = ncaps;
 
  cleanup:
     virNodeDeviceObjEndAPI(&obj);
@@ -353,9 +331,10 @@ nodeDeviceListCaps(virNodeDevicePtr device,
 {
     virNodeDeviceObjPtr obj;
     virNodeDeviceDefPtr def;
-    virNodeDevCapsDefPtr caps;
+    virNodeDevCapType *list = NULL;
     int ncaps = 0;
     int ret = -1;
+    size_t i = 0;
 
     if (!(obj = nodeDeviceObjFindByName(device->name)))
         return -1;
@@ -364,46 +343,28 @@ nodeDeviceListCaps(virNodeDevicePtr device,
     if (virNodeDeviceListCapsEnsureACL(device->conn, def) < 0)
         goto cleanup;
 
-    for (caps = def->caps; caps && ncaps < maxnames; caps = caps->next) {
+    if ((ncaps = virNodeDeviceCapsListExport(def, &list)) < 0)
-        if (VIR_STRDUP(names[ncaps++], virNodeDevCapTypeToString(caps->data.type)) < 0)
+        goto cleanup;
+
+    if (ncaps > maxnames)
+        ncaps = maxnames;
+
+    for (i = 0; i < ncaps; i++) {
+        if (VIR_STRDUP(names[i], virNodeDevCapTypeToString(list[i])) < 0)
             goto cleanup;
-
-        if (caps->data.type == VIR_NODE_DEV_CAP_SCSI_HOST) {
-            if (ncaps < maxnames &&
-                caps->data.scsi_host.flags &
-                VIR_NODE_DEV_CAP_FLAG_HBA_FC_HOST) {
-                if (VIR_STRDUP(names[ncaps++],
-                               virNodeDevCapTypeToString(VIR_NODE_DEV_CAP_FC_HOST)) < 0)
-                    goto cleanup;
-            }
-
-            if (ncaps < maxnames &&
-                caps->data.scsi_host.flags &
-                VIR_NODE_DEV_CAP_FLAG_HBA_VPORT_OPS) {
-                if (VIR_STRDUP(names[ncaps++],
-                               virNodeDevCapTypeToString(VIR_NODE_DEV_CAP_VPORTS)) < 0)
-                    goto cleanup;
-            }
-        }
-        if (caps->data.type == VIR_NODE_DEV_CAP_PCI_DEV) {
-            if (ncaps < maxnames &&
-                caps->data.pci_dev.flags &
-                VIR_NODE_DEV_CAP_FLAG_PCI_MDEV) {
-                if (VIR_STRDUP(names[ncaps++],
-                               virNodeDevCapTypeToString(VIR_NODE_DEV_CAP_MDEV_TYPES)) < 0)
-                    goto cleanup;
-            }
-        }
     }
+
     ret = ncaps;
 
  cleanup:
     virNodeDeviceObjEndAPI(&obj);
-    if (ret == -1) {
+    if (ret < 0) {
-        --ncaps;
+        size_t j;
-        while (--ncaps >= 0)
+        for (j = 0; j < i; j++)
-            VIR_FREE(names[ncaps]);
+            VIR_FREE(names[j]);
     }
+
+    VIR_FREE(list);
     return ret;
 }