[libvirt] [PATCH] LXC: Fix some error reporting in filesystem setup

[Daniel P. Berrange]

From: "Daniel P. Berrange" <berrange at redhat.com>

A couple of places in LXC setup for filesystems did not do
a "goto cleanup" after reporting errors. While fixing this,
also add in many more debug statements to aid troubleshooting

Signed-off-by: Daniel P. Berrange <berrange at redhat.com>
---
 src/lxc/lxc_container.c  | 23 ++++++++++++++++++-----
 src/lxc/lxc_controller.c |  6 ++++++
 2 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c
index 595c0f2..389c336 100644
--- a/src/lxc/lxc_container.c
+++ b/src/lxc/lxc_container.c
@@ -551,6 +551,8 @@ static int lxcContainerPrepareRoot(virDomainDefPtr def,
     char *dst;
     char *tmp;
 
+    VIR_DEBUG("Prepare root %d", root->type);
+
     if (root->type == VIR_DOMAIN_FS_TYPE_MOUNT)
         return 0;
 
@@ -1230,7 +1232,8 @@ static int lxcContainerMountFSBlockHelper(virDomainFSDefPtr fs,
         goto cleanup;
 
     if (format) {
-        VIR_DEBUG("Mount %s with detected format %s", src, format);
+        VIR_DEBUG("Mount '%s' on '%s' with detected format '%s'",
+                  src, fs->dst, format);
         if (mount(src, fs->dst, format, fsflags, NULL) < 0) {
             virReportSystemError(errno,
                                  _("Failed to mount device %s to %s as %s"),
@@ -1339,12 +1342,12 @@ static int lxcContainerMountFS(virDomainFSDefPtr fs,
         virReportError(VIR_ERR_INTERNAL_ERROR,
                        _("Unexpected filesystem type %s"),
                        virDomainFSTypeToString(fs->type));
-        break;
+        return -1;
     default:
         virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                        _("Cannot mount filesystem type %s"),
                        virDomainFSTypeToString(fs->type));
-        break;
+        return -1;
     }
     return 0;
 }
@@ -1885,18 +1888,26 @@ static int lxcContainerResolveSymlinks(virDomainDefPtr vmDef)
     char *newroot;
     size_t i;
 
+    VIR_DEBUG("Resolving filesystem symlinks");
     for (i = 0; i < vmDef->nfss; i++) {
+        VIR_DEBUG("Res %zu", i);
         virDomainFSDefPtr fs = vmDef->fss[i];
-        if (!fs->src)
+        if (!fs->src) {
+            VIR_DEBUG("Skip");
             continue;
-        if (virFileResolveAllLinks(fs->src, &newroot) < 0)
+        }
+        VIR_DEBUG("Resolving '%s'", fs->src);
+        if (virFileResolveAllLinks(fs->src, &newroot) < 0) {
+            VIR_DEBUG("Failed to resolve symlink at %s", fs->src);
             return -1;
+        }
 
         VIR_DEBUG("Resolved '%s' to %s", fs->src, newroot);
 
         VIR_FREE(fs->src);
         fs->src = newroot;
     }
+    VIR_DEBUG("Resolved all filesystem symlinks");
 
     return 0;
 }
@@ -2020,9 +2031,11 @@ static int lxcContainerChild(void *data)
         goto cleanup;
     }
 
+    VIR_DEBUG("Resolve t");
     if (lxcContainerResolveSymlinks(vmDef) < 0)
         goto cleanup;
 
+    VIR_DEBUG("Setting up pivot");
     if (lxcContainerSetupPivotRoot(vmDef, root,
                                    argv->ttyPaths, argv->nttyPaths,
                                    argv->securityDriver) < 0)
diff --git a/src/lxc/lxc_controller.c b/src/lxc/lxc_controller.c
index ef35c05..831dff8 100644
--- a/src/lxc/lxc_controller.c
+++ b/src/lxc/lxc_controller.c
@@ -450,6 +450,8 @@ static int virLXCControllerSetupLoopDevices(virLXCControllerPtr ctrl)
     size_t i;
     int ret = -1;
 
+    VIR_DEBUG("Setting up loop devices for filesystems");
+
     for (i = 0; i < ctrl->def->nfss; i++) {
         virDomainFSDefPtr fs = ctrl->def->fss[i];
         int fd;
@@ -492,9 +494,12 @@ static int virLXCControllerSetupLoopDevices(virLXCControllerPtr ctrl)
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                            _("fs driver %s is not supported"),
                            virDomainFSDriverTypeTypeToString(fs->fsdriver));
+            goto cleanup;
         }
     }
 
+    VIR_DEBUG("Setting up loop devices for disks");
+
     for (i = 0; i < ctrl->def->ndisks; i++) {
         virDomainDiskDefPtr disk = ctrl->def->disks[i];
         int fd;
@@ -548,6 +553,7 @@ static int virLXCControllerSetupLoopDevices(virLXCControllerPtr ctrl)
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
                            _("disk driver %s is not supported"),
                            disk->driverName);
+            goto cleanup;
         }
     }
 
-- 
1.8.3.1