qemu: Introduce qemuBuildFSDevCommandLine

Add new function to manage adding the -fsdev options to the
command line removing that task from the mainline qemuBuildCommandLine.
Alter the code slightly to perform the !caps and fsdev failure check
up front.

Since both qemuBuildFSStr and qemuBuildFSDevStr are local, make them
static and fix their prototypes to use the const virDomainDef as well.
Make some minor formatting changes for long lines.

Signed-off-by: John Ferlan <jferlan@redhat.com>

src/qemu/qemu_command.c

@@ -1982,8 +1982,9 @@ qemuBuildDiskDriveCommandLine(virCommandPtr cmd,
 }
 
 
-char *qemuBuildFSStr(virDomainFSDefPtr fs,
+static char *
-                     virQEMUCapsPtr qemuCaps ATTRIBUTE_UNUSED)
+qemuBuildFSStr(virDomainFSDefPtr fs,
+               virQEMUCapsPtr qemuCaps)
 {
     virBuffer opt = VIR_BUFFER_INITIALIZER;
     const char *driver = qemuDomainFSDriverTypeToString(fs->fsdriver);
@@ -2056,8 +2057,8 @@ char *qemuBuildFSStr(virDomainFSDefPtr fs,
 }
 
 
-char *
+static char *
-qemuBuildFSDevStr(virDomainDefPtr def,
+qemuBuildFSDevStr(const virDomainDef *def,
                   virDomainFSDefPtr fs,
                   virQEMUCapsPtr qemuCaps)
 {
@@ -2075,7 +2076,8 @@ qemuBuildFSDevStr(virDomainDefPtr def,
         virBufferAddLit(&opt, "virtio-9p-pci");
 
     virBufferAsprintf(&opt, ",id=%s", fs->info.alias);
-    virBufferAsprintf(&opt, ",fsdev=%s%s", QEMU_FSDEV_HOST_PREFIX, fs->info.alias);
+    virBufferAsprintf(&opt, ",fsdev=%s%s",
+                      QEMU_FSDEV_HOST_PREFIX, fs->info.alias);
     virBufferAsprintf(&opt, ",mount_tag=%s", fs->dst);
 
     if (qemuBuildDeviceAddressStr(&opt, def, &fs->info, qemuCaps) < 0)
@@ -2092,6 +2094,40 @@ qemuBuildFSDevStr(virDomainDefPtr def,
 }
 
 
+static int
+qemuBuildFSDevCommandLine(virCommandPtr cmd,
+                          const virDomainDef *def,
+                          virQEMUCapsPtr qemuCaps)
+{
+    size_t i;
+
+    if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_FSDEV) && def->nfss) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                       _("filesystem passthrough not supported by this QEMU"));
+        return -1;
+    }
+
+    for (i = 0; i < def->nfss; i++) {
+        char *optstr;
+        virDomainFSDefPtr fs = def->fss[i];
+
+        virCommandAddArg(cmd, "-fsdev");
+        if (!(optstr = qemuBuildFSStr(fs, qemuCaps)))
+            return -1;
+        virCommandAddArg(cmd, optstr);
+        VIR_FREE(optstr);
+
+        virCommandAddArg(cmd, "-device");
+        if (!(optstr = qemuBuildFSDevStr(def, fs, qemuCaps)))
+            return -1;
+        virCommandAddArg(cmd, optstr);
+        VIR_FREE(optstr);
+    }
+
+    return 0;
+}
+
+
 static int
 qemuControllerModelUSBToCaps(int model)
 {
@@ -8013,30 +8049,8 @@ qemuBuildCommandLine(virConnectPtr conn,
                                       emitBootindex) < 0)
         goto error;
 
-    if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_FSDEV)) {
+    if (qemuBuildFSDevCommandLine(cmd, def, qemuCaps) < 0)
-        for (i = 0; i < def->nfss; i++) {
+        goto error;
-            char *optstr;
-            virDomainFSDefPtr fs = def->fss[i];
-
-            virCommandAddArg(cmd, "-fsdev");
-            if (!(optstr = qemuBuildFSStr(fs, qemuCaps)))
-                goto error;
-            virCommandAddArg(cmd, optstr);
-            VIR_FREE(optstr);
-
-            virCommandAddArg(cmd, "-device");
-            if (!(optstr = qemuBuildFSDevStr(def, fs, qemuCaps)))
-                goto error;
-            virCommandAddArg(cmd, optstr);
-            VIR_FREE(optstr);
-        }
-    } else {
-        if (def->nfss) {
-            virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
-                           _("filesystem passthrough not supported by this QEMU"));
-            goto error;
-        }
-    }
 
     if (!def->nnets) {
         /* If we have -device, then we set -nodefault already */

src/qemu/qemu_command.h

@@ -117,17 +117,13 @@ char *qemuBuildDriveStr(virConnectPtr conn,
                         virDomainDiskDefPtr disk,
                         bool bootable,
                         virQEMUCapsPtr qemuCaps);
-char *qemuBuildFSStr(virDomainFSDefPtr fs,
-                     virQEMUCapsPtr qemuCaps);
 
 /* Current, best practice */
 char *qemuBuildDriveDevStr(const virDomainDef *def,
                            virDomainDiskDefPtr disk,
                            int bootindex,
                            virQEMUCapsPtr qemuCaps);
-char *qemuBuildFSDevStr(virDomainDefPtr domainDef,
+
-                        virDomainFSDefPtr fs,
-                        virQEMUCapsPtr qemuCaps);
 /* Current, best practice */
 char *qemuBuildControllerDevStr(const virDomainDef *domainDef,
                                 virDomainControllerDefPtr def,