nfsd4: setclientid_confirm callback-change fixes

[safe/jmp/linux-2.6] / drivers / virtio / virtio_ring.c

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 9849bab..5c52369 100644 (file)
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -18,19 +18,26 @@
  */
 #include <linux/virtio.h>
 #include <linux/virtio_ring.h>
+#include <linux/virtio_config.h>
 #include <linux/device.h>
 
 #ifdef DEBUG
 /* For development, we want to crash whenever the ring is screwed. */
-#define BAD_RING(vq, fmt...)                   \
-       do { dev_err(&vq->vq.vdev->dev, fmt); BUG(); } while(0)
-#define START_USE(vq) \
-       do { if ((vq)->in_use) panic("in_use = %i\n", (vq)->in_use); (vq)->in_use = __LINE__; mb(); } while(0)
-#define END_USE(vq) \
-       do { BUG_ON(!(vq)->in_use); (vq)->in_use = 0; mb(); } while(0)
+#define BAD_RING(_vq, fmt...)                  \
+       do { dev_err(&(_vq)->vq.vdev->dev, fmt); BUG(); } while(0)
+/* Caller is supposed to guarantee no reentry. */
+#define START_USE(_vq)                                         \
+       do {                                                    \
+               if ((_vq)->in_use)                              \
+                       panic("in_use = %i\n", (_vq)->in_use);  \
+               (_vq)->in_use = __LINE__;                       \
+               mb();                                           \
+       } while(0)
+#define END_USE(_vq) \
+       do { BUG_ON(!(_vq)->in_use); (_vq)->in_use = 0; mb(); } while(0)
 #else
-#define BAD_RING(vq, fmt...)                   \
-       do { dev_err(&vq->vq.vdev->dev, fmt); (vq)->broken = true; } while(0)
+#define BAD_RING(_vq, fmt...)                  \
+       do { dev_err(&_vq->vq.vdev->dev, fmt); (_vq)->broken = true; } while(0)
 #define START_USE(vq)
 #define END_USE(vq)
 #endif
@@ -87,8 +94,11 @@ static int vring_add_buf(struct virtqueue *_vq,
        if (vq->num_free < out + in) {
                pr_debug("Can't add buf len %i - avail = %i\n",
                         out + in, vq->num_free);
-               /* We notify *even if* VRING_USED_F_NO_NOTIFY is set here. */
-               vq->notify(&vq->vq);
+               /* FIXME: for historical reasons, we force a notify here if
+                * there are outgoing parts to the buffer.  Presumably the
+                * host should service the ring ASAP. */
+               if (out)
+                       vq->notify(&vq->vq);
                END_USE(vq);
                return -ENOSPC;
        }
@@ -99,16 +109,14 @@ static int vring_add_buf(struct virtqueue *_vq,
        head = vq->free_head;
        for (i = vq->free_head; out; i = vq->vring.desc[i].next, out--) {
                vq->vring.desc[i].flags = VRING_DESC_F_NEXT;
-               vq->vring.desc[i].addr = (page_to_pfn(sg_page(sg))<<PAGE_SHIFT)
-                       + sg->offset;
+               vq->vring.desc[i].addr = sg_phys(sg);
                vq->vring.desc[i].len = sg->length;
                prev = i;
                sg++;
        }
        for (; in; i = vq->vring.desc[i].next, in--) {
                vq->vring.desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE;
-               vq->vring.desc[i].addr = (page_to_pfn(sg_page(sg))<<PAGE_SHIFT)
-                       + sg->offset;
+               vq->vring.desc[i].addr = sg_phys(sg);
                vq->vring.desc[i].len = sg->length;
                prev = i;
                sg++;
@@ -186,6 +194,11 @@ static void *vring_get_buf(struct virtqueue *_vq, unsigned int *len)
 
        START_USE(vq);
 
+       if (unlikely(vq->broken)) {
+               END_USE(vq);
+               return NULL;
+       }
+
        if (!more_used(vq)) {
                pr_debug("No more buffers in queue\n");
                END_USE(vq);
@@ -216,10 +229,7 @@ static void vring_disable_cb(struct virtqueue *_vq)
 {
        struct vring_virtqueue *vq = to_vvq(_vq);
 
-       START_USE(vq);
-       BUG_ON(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT);
        vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
-       END_USE(vq);
 }
 
 static bool vring_enable_cb(struct virtqueue *_vq)
@@ -227,14 +237,12 @@ static bool vring_enable_cb(struct virtqueue *_vq)
        struct vring_virtqueue *vq = to_vvq(_vq);
 
        START_USE(vq);
-       BUG_ON(!(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT));
 
        /* We optimistically turn back on interrupts, then check if there was
         * more to do. */
        vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT;
        mb();
        if (unlikely(more_used(vq))) {
-               vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
                END_USE(vq);
                return false;
        }
@@ -261,6 +269,7 @@ irqreturn_t vring_interrupt(int irq, void *_vq)
 
        return IRQ_HANDLED;
 }
+EXPORT_SYMBOL_GPL(vring_interrupt);
 
 static struct virtqueue_ops vring_vq_ops = {
        .add_buf = vring_add_buf,
@@ -271,6 +280,7 @@ static struct virtqueue_ops vring_vq_ops = {
 };
 
 struct virtqueue *vring_new_virtqueue(unsigned int num,
+                                     unsigned int vring_align,
                                      struct virtio_device *vdev,
                                      void *pages,
                                      void (*notify)(struct virtqueue *),
@@ -289,7 +299,7 @@ struct virtqueue *vring_new_virtqueue(unsigned int num,
        if (!vq)
                return NULL;
 
-       vring_init(&vq->vring, num, pages, PAGE_SIZE);
+       vring_init(&vq->vring, num, pages, vring_align);
        vq->vq.callback = callback;
        vq->vq.vdev = vdev;
        vq->vq.vq_ops = &vring_vq_ops;
@@ -313,9 +323,27 @@ struct virtqueue *vring_new_virtqueue(unsigned int num,
 
        return &vq->vq;
 }
+EXPORT_SYMBOL_GPL(vring_new_virtqueue);
 
 void vring_del_virtqueue(struct virtqueue *vq)
 {
        kfree(to_vvq(vq));
 }
+EXPORT_SYMBOL_GPL(vring_del_virtqueue);
+
+/* Manipulates transport-specific feature bits. */
+void vring_transport_features(struct virtio_device *vdev)
+{
+       unsigned int i;
+
+       for (i = VIRTIO_TRANSPORT_F_START; i < VIRTIO_TRANSPORT_F_END; i++) {
+               switch (i) {
+               default:
+                       /* We don't understand this bit. */
+                       clear_bit(i, vdev->features);
+               }
+       }
+}
+EXPORT_SYMBOL_GPL(vring_transport_features);
 
+MODULE_LICENSE("GPL");