[Qemu-block] [PATCH v4 6/6] tests/virtio-blk: add test for WRITE_ZEROES command

[Stefano Garzarella]

If the WRITE_ZEROES feature is enabled, we check this command
in the test_basic().

Reviewed-by: Michael S. Tsirkin <address@hidden>
Reviewed-by: Stefan Hajnoczi <address@hidden>
Acked-by: Thomas Huth <address@hidden>
Signed-off-by: Stefano Garzarella <address@hidden>
---
 tests/virtio-blk-test.c | 60 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

diff --git a/tests/virtio-blk-test.c b/tests/virtio-blk-test.c
index 0739498da7..35bd92dbfc 100644
--- a/tests/virtio-blk-test.c
+++ b/tests/virtio-blk-test.c
@@ -244,6 +244,66 @@ static void test_basic(QVirtioDevice *dev, QGuestAllocator 
*alloc,
 
     guest_free(alloc, req_addr);
 
+    if (features & (1u << VIRTIO_BLK_F_WRITE_ZEROES)) {
+        struct virtio_blk_discard_write_zeroes dwz_hdr;
+        void *expected;
+
+        /*
+         * WRITE_ZEROES request on the same sector of previous test where
+         * we wrote "TEST".
+         */
+        req.type = VIRTIO_BLK_T_WRITE_ZEROES;
+        req.data = (char *) &dwz_hdr;
+        dwz_hdr.sector = 0;
+        dwz_hdr.num_sectors = 1;
+        dwz_hdr.flags = 0;
+
+        req_addr = virtio_blk_request(alloc, dev, &req, sizeof(dwz_hdr));
+
+        free_head = qvirtqueue_add(vq, req_addr, 16, false, true);
+        qvirtqueue_add(vq, req_addr + 16, sizeof(dwz_hdr), false, true);
+        qvirtqueue_add(vq, req_addr + 16 + sizeof(dwz_hdr), 1, true, false);
+
+        qvirtqueue_kick(dev, vq, free_head);
+
+        qvirtio_wait_used_elem(dev, vq, free_head, NULL,
+                               QVIRTIO_BLK_TIMEOUT_US);
+        status = readb(req_addr + 16 + sizeof(dwz_hdr));
+        g_assert_cmpint(status, ==, 0);
+
+        guest_free(alloc, req_addr);
+
+        /* Read request to check if the sector contains all zeroes */
+        req.type = VIRTIO_BLK_T_IN;
+        req.ioprio = 1;
+        req.sector = 0;
+        req.data = g_malloc0(512);
+
+        req_addr = virtio_blk_request(alloc, dev, &req, 512);
+
+        g_free(req.data);
+
+        free_head = qvirtqueue_add(vq, req_addr, 16, false, true);
+        qvirtqueue_add(vq, req_addr + 16, 512, true, true);
+        qvirtqueue_add(vq, req_addr + 528, 1, true, false);
+
+        qvirtqueue_kick(dev, vq, free_head);
+
+        qvirtio_wait_used_elem(dev, vq, free_head, NULL,
+                               QVIRTIO_BLK_TIMEOUT_US);
+        status = readb(req_addr + 528);
+        g_assert_cmpint(status, ==, 0);
+
+        data = g_malloc(512);
+        expected = g_malloc0(512);
+        memread(req_addr + 16, data, 512);
+        g_assert_cmpmem(data, 512, expected, 512);
+        g_free(expected);
+        g_free(data);
+
+        guest_free(alloc, req_addr);
+    }
+
     if (features & (1u << VIRTIO_F_ANY_LAYOUT)) {
         /* Write and read with 2 descriptor layout */
         /* Write request */
-- 
2.20.1