[Qemu-block] [PATCH v7 18/20] tests: Use null-co:// instead of /dev/null

[Fam Zheng]

With image locking, opening /dev/null can fail when multiple tests run
in parallel (make -j2, for example). Use null-co:// as the null protocol
doesn't do image locking.

While it's arguable we could special-case /dev/null, /dev/zero,
/dev/urandom etc in raw-posix driver, it is not really necessary because
user can always specify lock-mode=off when it is appropriate. So let's
write sensible testing code too.

Signed-off-by: Fam Zheng <address@hidden>
Reviewed-by: Max Reitz <address@hidden>
---
 tests/drive_del-test.c    | 2 +-
 tests/nvme-test.c         | 2 +-
 tests/usb-hcd-uhci-test.c | 2 +-
 tests/usb-hcd-xhci-test.c | 2 +-
 tests/virtio-blk-test.c   | 2 +-
 tests/virtio-scsi-test.c  | 4 ++--
 6 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/tests/drive_del-test.c b/tests/drive_del-test.c
index 121b9c9..2175139 100644
--- a/tests/drive_del-test.c
+++ b/tests/drive_del-test.c
@@ -92,7 +92,7 @@ static void test_after_failed_device_add(void)
 static void test_drive_del_device_del(void)
 {
     /* Start with a drive used by a device that unplugs instantaneously */
-    qtest_start("-drive if=none,id=drive0,file=/dev/null,format=raw"
+    qtest_start("-drive if=none,id=drive0,file=null-co://,format=raw"
                 " -device virtio-scsi-pci"
                 " -device scsi-hd,drive=drive0,id=dev0");
 
diff --git a/tests/nvme-test.c b/tests/nvme-test.c
index c8bece4..7674a44 100644
--- a/tests/nvme-test.c
+++ b/tests/nvme-test.c
@@ -22,7 +22,7 @@ int main(int argc, char **argv)
     g_test_init(&argc, &argv, NULL);
     qtest_add_func("/nvme/nop", nop);
 
-    qtest_start("-drive id=drv0,if=none,file=/dev/null,format=raw "
+    qtest_start("-drive id=drv0,if=none,file=null-co://,format=raw "
                 "-device nvme,drive=drv0,serial=foo");
     ret = g_test_run();
 
diff --git a/tests/usb-hcd-uhci-test.c b/tests/usb-hcd-uhci-test.c
index 5cd59ad..3684503 100644
--- a/tests/usb-hcd-uhci-test.c
+++ b/tests/usb-hcd-uhci-test.c
@@ -85,7 +85,7 @@ int main(int argc, char **argv)
     qtest_add_func("/uhci/pci/hotplug/usb-storage", test_usb_storage_hotplug);
 
     qtest_start("-device piix3-usb-uhci,id=uhci,addr=1d.0"
-                " -drive id=drive0,if=none,file=/dev/null,format=raw"
+                " -drive id=drive0,if=none,file=null-co://,format=raw"
                 " -device usb-tablet,bus=uhci.0,port=1");
     ret = g_test_run();
     qtest_end();
diff --git a/tests/usb-hcd-xhci-test.c b/tests/usb-hcd-xhci-test.c
index 22513e9..031764d 100644
--- a/tests/usb-hcd-xhci-test.c
+++ b/tests/usb-hcd-xhci-test.c
@@ -89,7 +89,7 @@ int main(int argc, char **argv)
     qtest_add_func("/xhci/pci/hotplug/usb-uas", test_usb_uas_hotplug);
 
     qtest_start("-device nec-usb-xhci,id=xhci"
-                " -drive id=drive0,if=none,file=/dev/null,format=raw");
+                " -drive id=drive0,if=none,file=null-co://,format=raw");
     ret = g_test_run();
     qtest_end();
 
diff --git a/tests/virtio-blk-test.c b/tests/virtio-blk-test.c
index 811cf75..5dba567 100644
--- a/tests/virtio-blk-test.c
+++ b/tests/virtio-blk-test.c
@@ -66,7 +66,7 @@ static QPCIBus *pci_test_start(void)
     tmp_path = drive_create();
 
     cmdline = g_strdup_printf("-drive if=none,id=drive0,file=%s,format=raw "
-                        "-drive if=none,id=drive1,file=/dev/null,format=raw "
+                        "-drive if=none,id=drive1,file=null-co://,format=raw "
                         "-device virtio-blk-pci,id=drv0,drive=drive0,"
                         "addr=%x.%x",
                         tmp_path, PCI_SLOT, PCI_FN);
diff --git a/tests/virtio-scsi-test.c b/tests/virtio-scsi-test.c
index f1489e6..3c2f5df 100644
--- a/tests/virtio-scsi-test.c
+++ b/tests/virtio-scsi-test.c
@@ -40,7 +40,7 @@ static void qvirtio_scsi_start(const char *extra_opts)
     char *cmdline;
 
     cmdline = g_strdup_printf(
-                "-drive id=drv0,if=none,file=/dev/null,format=raw "
+                "-drive id=drv0,if=none,file=null-co://,format=raw "
                 "-device virtio-scsi-pci,id=vs0 "
                 "-device scsi-hd,bus=vs0.0,drive=drv0 %s",
                 extra_opts ? : "");
@@ -192,7 +192,7 @@ static void hotplug(void)
 {
     QDict *response;
 
-    qvirtio_scsi_start("-drive id=drv1,if=none,file=/dev/null,format=raw");
+    qvirtio_scsi_start("-drive id=drv1,if=none,file=null-co://,format=raw");
     response = qmp("{\"execute\": \"device_add\","
                    " \"arguments\": {"
                    "   \"driver\": \"scsi-hd\","
-- 
2.7.4