[libvirt RFCv11 17/33] qemu: saveimage: wire up saveimage code with the multifd helper

[Claudio Fontana]

prepare to use the multifd helper.

Signed-off-by: Claudio Fontana <cfont...@suse.de>
---
 src/qemu/qemu_saveimage.c | 41 ++++++++++++++++++++++++++++++++++-----
 1 file changed, 36 insertions(+), 5 deletions(-)

diff --git a/src/qemu/qemu_saveimage.c b/src/qemu/qemu_saveimage.c
index 6418114d8a..8af9b92b35 100644
--- a/src/qemu/qemu_saveimage.c
+++ b/src/qemu/qemu_saveimage.c
@@ -17,6 +17,7 @@
  */
 
 #include <config.h>
+#include <configmake.h>
 
 #include "qemu_saveimage.h"
 #include "qemu_domain.h"
@@ -542,7 +543,7 @@ qemuSaveImageCreate(virQEMUDriver *driver,
                     const char *path,
                     virQEMUSaveData *data,
                     virCommand *compressor,
-                    int nconn G_GNUC_UNUSED,
+                    int nconn,
                     unsigned int flags,
                     virDomainAsyncJob asyncJob)
 {
@@ -566,10 +567,40 @@ qemuSaveImageCreate(virQEMUDriver *driver,
         goto cleanup;
     if (virQEMUSaveDataWrite(data, saveFd.fd, saveFd.path) < 0)
         goto cleanup;
-
-    /* Perform the migration */
-    if (qemuMigrationSrcToFile(driver, vm, saveFd.fd, compressor, asyncJob) < 
0)
-        goto cleanup;
+    if (nconn > 0) {
+        if (virQEMUSaveFdAddChannels(&saveFd, nconn) < 0)
+            goto cleanup;
+    }
+    if (flags & VIR_DOMAIN_SAVE_PARALLEL) {
+        g_autoptr(virCommand) cmd = NULL;
+        g_autofree char *helper_path = NULL;
+        qemuDomainObjPrivate *priv = vm->privateData;
+        g_autofree char *sun_path = g_strdup_printf("%s/save-multifd.sock", 
priv->libDir);
+        char buf[1];
+        int helper_out = -1;
+        if (!(helper_path = virFileFindResource("libvirt_multifd_helper",
+                                                abs_top_builddir "/src",
+                                                LIBEXECDIR)))
+            goto cleanup;
+        cmd = virCommandNewArgList(helper_path, sun_path, saveFd.path, NULL);
+        virCommandAddArgFormat(cmd, "%d", nconn);
+        virCommandAddArgFormat(cmd, "%d", saveFd.fd);
+        virCommandPassFD(cmd, saveFd.fd, 0);
+        virCommandSetOutputFD(cmd, &helper_out); /* should create pipe 
automagically */
+        if (virCommandRunAsync(cmd, NULL) < 0)
+            goto cleanup;
+        if (saferead(helper_out, &buf, 1) != 1 || buf[0] != 'R')
+            goto cleanup;
+        if (chown(sun_path, cfg->user, cfg->group) < 0)
+            goto cleanup;
+        /* still using single fd migration for now */
+        if (qemuMigrationSrcToFile(driver, vm, saveFd.fd, compressor, 
asyncJob) < 0)
+            goto cleanup;
+    } else {
+        /* Perform non-parallel migration to file */
+        if (qemuMigrationSrcToFile(driver, vm, saveFd.fd, compressor, 
asyncJob) < 0)
+            goto cleanup;
+    }
 
     if (virQEMUSaveFdClose(&saveFd, vm) < 0)
         goto cleanup;
-- 
2.26.2