libqos: Added indirect descriptor support to virtio implementation

Add functions necessary for working with indirect descriptors.
Add test using new functions.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Marc Marí <marc.mari.barcelo@gmail.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

3 files changed, 95 insertions, 1 deletions

diff --git a/tests/libqos/virtio-pci.c b/tests/libqos/virtio-pci.c
index 12b06a2f53..cf15f7a45b 100644
--- a/tests/libqos/virtio-pci.c
+++ b/tests/libqos/virtio-pci.c
@@ -107,6 +107,12 @@ static void qvirtio_pci_set_features(QVirtioDevice *d, uint32_t features)
     qpci_io_writel(dev->pdev, dev->addr + QVIRTIO_GUEST_FEATURES, features);
 }
 
+static uint32_t qvirtio_pci_get_guest_features(QVirtioDevice *d)
+{
+    QVirtioPCIDevice *dev = (QVirtioPCIDevice *)d;
+    return qpci_io_readl(dev->pdev, dev->addr + QVIRTIO_GUEST_FEATURES);
+}
+
 static uint8_t qvirtio_pci_get_status(QVirtioDevice *d)
 {
     QVirtioPCIDevice *dev = (QVirtioPCIDevice *)d;
@@ -146,10 +152,12 @@ static void qvirtio_pci_set_queue_address(QVirtioDevice *d, uint32_t pfn)
 static QVirtQueue *qvirtio_pci_virtqueue_setup(QVirtioDevice *d,
                                         QGuestAllocator *alloc, uint16_t index)
 {
+    uint32_t feat;
     uint64_t addr;
     QVirtQueue *vq;
 
     vq = g_malloc0(sizeof(*vq));
+    feat = qvirtio_pci_get_guest_features(d);
 
     qvirtio_pci_queue_select(d, index);
     vq->index = index;
@@ -157,6 +165,7 @@ static QVirtQueue *qvirtio_pci_virtqueue_setup(QVirtioDevice *d,
     vq->free_head = 0;
     vq->num_free = vq->size;
     vq->align = QVIRTIO_PCI_ALIGN;
+    vq->indirect = (feat & QVIRTIO_F_RING_INDIRECT_DESC) != 0;
 
     /* Check different than 0 */
     g_assert_cmpint(vq->size, !=, 0);
@@ -186,6 +195,7 @@ const QVirtioBus qvirtio_pci = {
     .config_readq = qvirtio_pci_config_readq,
     .get_features = qvirtio_pci_get_features,
     .set_features = qvirtio_pci_set_features,
+    .get_guest_features = qvirtio_pci_get_guest_features,
     .get_status = qvirtio_pci_get_status,
     .set_status = qvirtio_pci_set_status,
     .get_isr_status = qvirtio_pci_get_isr_status,
diff --git a/tests/libqos/virtio.c b/tests/libqos/virtio.c
index de92642819..b1cab1f699 100644
--- a/tests/libqos/virtio.c
+++ b/tests/libqos/virtio.c
@@ -116,6 +116,51 @@ void qvring_init(const QGuestAllocator *alloc, QVirtQueue *vq, uint64_t addr)
     writew(vq->used, 0);
 }
 
+QVRingIndirectDesc *qvring_indirect_desc_setup(QVirtioDevice *d,
+                                        QGuestAllocator *alloc, uint16_t elem)
+{
+    int i;
+    QVRingIndirectDesc *indirect = g_malloc(sizeof(*indirect));
+
+    indirect->index = 0;
+    indirect->elem = elem;
+    indirect->desc = guest_alloc(alloc, sizeof(QVRingDesc)*elem);
+
+    for (i = 0; i < elem - 1; ++i) {
+        /* indirect->desc[i].addr */
+        writeq(indirect->desc + (16 * i), 0);
+        /* indirect->desc[i].flags */
+        writew(indirect->desc + (16 * i) + 12, QVRING_DESC_F_NEXT);
+        /* indirect->desc[i].next */
+        writew(indirect->desc + (16 * i) + 14, i + 1);
+    }
+
+    return indirect;
+}
+
+void qvring_indirect_desc_add(QVRingIndirectDesc *indirect, uint64_t data,
+                                                    uint32_t len, bool write)
+{
+    uint16_t flags;
+
+    g_assert_cmpint(indirect->index, <, indirect->elem);
+
+    flags = readw(indirect->desc + (16 * indirect->index) + 12);
+
+    if (write) {
+        flags |= QVRING_DESC_F_WRITE;
+    }
+
+    /* indirect->desc[indirect->index].addr */
+    writeq(indirect->desc + (16 * indirect->index), data);
+    /* indirect->desc[indirect->index].len */
+    writel(indirect->desc + (16 * indirect->index) + 8, len);
+    /* indirect->desc[indirect->index].flags */
+    writew(indirect->desc + (16 * indirect->index) + 12, flags);
+
+    indirect->index++;
+}
+
 uint32_t qvirtqueue_add(QVirtQueue *vq, uint64_t data, uint32_t len, bool write,
                                                                     bool next)
 {
@@ -140,6 +185,25 @@ uint32_t qvirtqueue_add(QVirtQueue *vq, uint64_t data, uint32_t len, bool write,
     return vq->free_head++; /* Return and increase, in this order */
 }
 
+uint32_t qvirtqueue_add_indirect(QVirtQueue *vq, QVRingIndirectDesc *indirect)
+{
+    g_assert(vq->indirect);
+    g_assert_cmpint(vq->size, >=, indirect->elem);
+    g_assert_cmpint(indirect->index, ==, indirect->elem);
+
+    vq->num_free--;
+
+    /* vq->desc[vq->free_head].addr */
+    writeq(vq->desc + (16 * vq->free_head), indirect->desc);
+    /* vq->desc[vq->free_head].len */
+    writel(vq->desc + (16 * vq->free_head) + 8,
+                                        sizeof(QVRingDesc) * indirect->elem);
+    /* vq->desc[vq->free_head].flags */
+    writew(vq->desc + (16 * vq->free_head) + 12, QVRING_DESC_F_INDIRECT);
+
+    return vq->free_head++; /* Return and increase, in this order */
+}
+
 void qvirtqueue_kick(const QVirtioBus *bus, QVirtioDevice *d, QVirtQueue *vq,
                                                             uint32_t free_head)
 {
diff --git a/tests/libqos/virtio.h b/tests/libqos/virtio.h
index aba5a1e12c..1860660dfd 100644
--- a/tests/libqos/virtio.h
+++ b/tests/libqos/virtio.h
@@ -22,6 +22,11 @@
 #define QVIRTIO_NET_DEVICE_ID   0x1
 #define QVIRTIO_BLK_DEVICE_ID   0x2
 
+#define QVIRTIO_F_NOTIFY_ON_EMPTY       0x01000000
+#define QVIRTIO_F_ANY_LAYOUT            0x08000000
+#define QVIRTIO_F_RING_INDIRECT_DESC    0x10000000
+#define QVIRTIO_F_RING_EVENT_IDX        0x20000000
+
 #define QVRING_DESC_F_NEXT      0x1
 #define QVRING_DESC_F_WRITE     0x2
 #define QVRING_DESC_F_INDIRECT  0x4
@@ -74,8 +79,15 @@ typedef struct QVirtQueue {
     uint32_t free_head;
     uint32_t num_free;
     uint32_t align;
+    bool indirect;
 } QVirtQueue;
 
+typedef struct QVRingIndirectDesc {
+    uint64_t desc; /* This points to an array fo QVRingDesc */
+    uint16_t index;
+    uint16_t elem;
+} QVRingIndirectDesc;
+
 typedef struct QVirtioBus {
     uint8_t (*config_readb)(QVirtioDevice *d, void *addr);
     uint16_t (*config_readw)(QVirtioDevice *d, void *addr);
@@ -85,9 +97,12 @@ typedef struct QVirtioBus {
     /* Get features of the device */
     uint32_t (*get_features)(QVirtioDevice *d);
 
-    /* Get features of the device */
+    /* Set features of the device */
     void (*set_features)(QVirtioDevice *d, uint32_t features);
 
+    /* Get features of the guest */
+    uint32_t (*get_guest_features)(QVirtioDevice *d);
+
     /* Get status of the device */
     uint8_t (*get_status)(QVirtioDevice *d);
 
@@ -144,8 +159,13 @@ QVirtQueue *qvirtqueue_setup(const QVirtioBus *bus, QVirtioDevice *d,
                                         QGuestAllocator *alloc, uint16_t index);
 
 void qvring_init(const QGuestAllocator *alloc, QVirtQueue *vq, uint64_t addr);
+QVRingIndirectDesc *qvring_indirect_desc_setup(QVirtioDevice *d,
+                                        QGuestAllocator *alloc, uint16_t elem);
+void qvring_indirect_desc_add(QVRingIndirectDesc *indirect, uint64_t data,
+                                                    uint32_t len, bool write);
 uint32_t qvirtqueue_add(QVirtQueue *vq, uint64_t data, uint32_t len, bool write,
                                                                     bool next);
+uint32_t qvirtqueue_add_indirect(QVirtQueue *vq, QVRingIndirectDesc *indirect);
 void qvirtqueue_kick(const QVirtioBus *bus, QVirtioDevice *d, QVirtQueue *vq,
                                                             uint32_t free_head);