From e1a17bbb0ee4fb11526e46f5aecf8b7ebaafdca4 Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Wed, 16 Nov 2011 13:02:57 +0100
Subject: [PATCH] virtio-pci: allocate vq in vp_find_vq

Another common bit that can be made generic.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 src/virtio-blk.c | 11 ++++-------
 src/virtio-pci.c | 22 +++++++++++++++++-----
 src/virtio-pci.h |  2 +-
 3 files changed, 22 insertions(+), 13 deletions(-)

diff --git a/src/virtio-blk.c b/src/virtio-blk.c
index 9ed82e0..b869189 100644
--- a/src/virtio-blk.c
+++ b/src/virtio-blk.c
@@ -103,20 +103,17 @@ init_virtio_blk(struct pci_device *pci)
     dprintf(1, "found virtio-blk at %x:%x\n", pci_bdf_to_bus(bdf),
             pci_bdf_to_dev(bdf));
     struct virtiodrive_s *vdrive_g = malloc_fseg(sizeof(*vdrive_g));
-    struct vring_virtqueue *vq = memalign_low(PAGE_SIZE, sizeof(*vq));
-    if (!vdrive_g || !vq) {
+    if (!vdrive_g) {
         warn_noalloc();
-        goto fail;
+        return;
     }
     memset(vdrive_g, 0, sizeof(*vdrive_g));
-    memset(vq, 0, sizeof(*vq));
     vdrive_g->drive.type = DTYPE_VIRTIO_BLK;
     vdrive_g->drive.cntl_id = bdf;
-    vdrive_g->vq = vq;
 
     u16 ioaddr = vp_init_simple(bdf);
     vdrive_g->ioaddr = ioaddr;
-    if (vp_find_vq(ioaddr, 0, vdrive_g->vq) < 0 ) {
+    if (vp_find_vq(ioaddr, 0, &vdrive_g->vq) < 0 ) {
         dprintf(1, "fail to find vq for virtio-blk %x:%x\n",
                 pci_bdf_to_bus(bdf), pci_bdf_to_dev(bdf));
         goto fail;
@@ -154,8 +151,8 @@ init_virtio_blk(struct pci_device *pci)
     return;
 
 fail:
+    free(vdrive_g->vq);
     free(vdrive_g);
-    free(vq);
 }
 
 void
diff --git a/src/virtio-pci.c b/src/virtio-pci.c
index 6a23d5d..7e0c1a5 100644
--- a/src/virtio-pci.c
+++ b/src/virtio-pci.c
@@ -21,12 +21,18 @@
 #include "util.h" // dprintf
 
 int vp_find_vq(unsigned int ioaddr, int queue_index,
-               struct vring_virtqueue *vq)
+               struct vring_virtqueue **p_vq)
 {
-   struct vring * vr = &vq->vring;
    u16 num;
 
    ASSERT32FLAT();
+   struct vring_virtqueue *vq = *p_vq = memalign_low(PAGE_SIZE, sizeof(*vq));
+   if (!vq) {
+       warn_noalloc();
+       goto fail;
+   }
+   memset(vq, 0, sizeof(*vq));
+
    /* select the queue */
 
    outw(queue_index, ioaddr + VIRTIO_PCI_QUEUE_SEL);
@@ -36,25 +42,26 @@ int vp_find_vq(unsigned int ioaddr, int queue_index,
    num = inw(ioaddr + VIRTIO_PCI_QUEUE_NUM);
    if (!num) {
        dprintf(1, "ERROR: queue size is 0\n");
-       return -1;
+       goto fail;
    }
 
    if (num > MAX_QUEUE_NUM) {
        dprintf(1, "ERROR: queue size %d > %d\n", num, MAX_QUEUE_NUM);
-       return -1;
+       goto fail;
    }
 
    /* check if the queue is already active */
 
    if (inl(ioaddr + VIRTIO_PCI_QUEUE_PFN)) {
        dprintf(1, "ERROR: queue already active\n");
-       return -1;
+       goto fail;
    }
 
    vq->queue_index = queue_index;
 
    /* initialize the queue */
 
+   struct vring * vr = &vq->vring;
    vring_init(vr, num, (unsigned char*)&vq->queue);
 
    /* activate the queue
@@ -66,6 +73,11 @@ int vp_find_vq(unsigned int ioaddr, int queue_index,
         ioaddr + VIRTIO_PCI_QUEUE_PFN);
 
    return num;
+
+fail:
+   free(vq);
+   *p_vq = NULL;
+   return -1;
 }
 
 u16 vp_init_simple(u16 bdf)
diff --git a/src/virtio-pci.h b/src/virtio-pci.h
index 60e7b35..e1d972d 100644
--- a/src/virtio-pci.h
+++ b/src/virtio-pci.h
@@ -101,5 +101,5 @@ static inline void vp_del_vq(unsigned int ioaddr, int queue_index)
 struct vring_virtqueue;
 u16 vp_init_simple(u16 bdf);
 int vp_find_vq(unsigned int ioaddr, int queue_index,
-               struct vring_virtqueue *vq);
+               struct vring_virtqueue **p_vq);
 #endif /* _VIRTIO_PCI_H_ */
-- 
2.25.1