Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

Pull virtio fixups from Michael Tsirkin:

 - Latest header update will break QEMU (if it's rebuilt with the new
   header) - and it seems that the code there is so fragile that any
   change in this header will break it. Add a better interface so users
   do not need to change their code every time that header changes.

 - Fix virtio console for spec compliance.

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio_console: reset on out of memory
  virtio_console: move removal code
  virtio_console: drop custom control queue cleanup
  virtio_console: free buffers after reset
  virtio: add ability to iterate over vqs
  virtio_console: don't tie bufs to a vq
  virtio_balloon: add array of stat names

3 files changed, 89 insertions, 86 deletions

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 468f06134012..21085515814f 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -422,7 +422,7 @@ static void reclaim_dma_bufs(void)
         }
 }
 
-static struct port_buffer *alloc_buf(struct virtqueue *vq, size_t buf_size,
+static struct port_buffer *alloc_buf(struct virtio_device *vdev, size_t buf_size,
                                      int pages)
 {
         struct port_buffer *buf;
@@ -445,16 +445,16 @@ static struct port_buffer *alloc_buf(struct virtqueue *vq, size_t buf_size,
                 return buf;
         }
 
-        if (is_rproc_serial(vq->vdev)) {
+        if (is_rproc_serial(vdev)) {
                 /*
                  * Allocate DMA memory from ancestor. When a virtio
                  * device is created by remoteproc, the DMA memory is
                  * associated with the grandparent device:
                  * vdev => rproc => platform-dev.
                  */
-                if (!vq->vdev->dev.parent || !vq->vdev->dev.parent->parent)
+                if (!vdev->dev.parent || !vdev->dev.parent->parent)
                         goto free_buf;
-                buf->dev = vq->vdev->dev.parent->parent;
+                buf->dev = vdev->dev.parent->parent;
 
                 /* Increase device refcnt to avoid freeing it */
                 get_device(buf->dev);
@@ -838,7 +838,7 @@ static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
 
         count = min((size_t)(32 * 1024), count);
 
-        buf = alloc_buf(port->out_vq, count, 0);
+        buf = alloc_buf(port->portdev->vdev, count, 0);
         if (!buf)
                 return -ENOMEM;
 
@@ -957,7 +957,7 @@ static ssize_t port_fops_splice_write(struct pipe_inode_info *pipe,
         if (ret < 0)
                 goto error_out;
 
-        buf = alloc_buf(port->out_vq, 0, pipe->nrbufs);
+        buf = alloc_buf(port->portdev->vdev, 0, pipe->nrbufs);
         if (!buf) {
                 ret = -ENOMEM;
                 goto error_out;
@@ -1374,7 +1374,7 @@ static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock)
 
         nr_added_bufs = 0;
         do {
-                buf = alloc_buf(vq, PAGE_SIZE, 0);
+                buf = alloc_buf(vq->vdev, PAGE_SIZE, 0);
                 if (!buf)
                         break;
 
@@ -1402,7 +1402,6 @@ static int add_port(struct ports_device *portdev, u32 id)
 {
         char debugfs_name[16];
         struct port *port;
-        struct port_buffer *buf;
         dev_t devt;
         unsigned int nr_added_bufs;
         int err;
@@ -1513,8 +1512,6 @@ static int add_port(struct ports_device *portdev, u32 id)
         return 0;
 
 free_inbufs:
-        while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
-                free_buf(buf, true);
 free_device:
         device_destroy(pdrvdata.class, port->dev->devt);
 free_cdev:
@@ -1539,34 +1536,14 @@ static void remove_port(struct kref *kref)
 
 static void remove_port_data(struct port *port)
 {
-        struct port_buffer *buf;
-
         spin_lock_irq(&port->inbuf_lock);
         /* Remove unused data this port might have received. */
         discard_port_data(port);
         spin_unlock_irq(&port->inbuf_lock);
 
-        /* Remove buffers we queued up for the Host to send us data in. */
-        do {
-                spin_lock_irq(&port->inbuf_lock);
-                buf = virtqueue_detach_unused_buf(port->in_vq);
-                spin_unlock_irq(&port->inbuf_lock);
-                if (buf)
-                        free_buf(buf, true);
-        } while (buf);
-
         spin_lock_irq(&port->outvq_lock);
         reclaim_consumed_buffers(port);
         spin_unlock_irq(&port->outvq_lock);
-
-        /* Free pending buffers from the out-queue. */
-        do {
-                spin_lock_irq(&port->outvq_lock);
-                buf = virtqueue_detach_unused_buf(port->out_vq);
-                spin_unlock_irq(&port->outvq_lock);
-                if (buf)
-                        free_buf(buf, true);
-        } while (buf);
 }
 
 /*
@@ -1791,13 +1768,24 @@ static void control_work_handler(struct work_struct *work)
         spin_unlock(&portdev->c_ivq_lock);
 }
 
+static void flush_bufs(struct virtqueue *vq, bool can_sleep)
+{
+        struct port_buffer *buf;
+        unsigned int len;
+
+        while ((buf = virtqueue_get_buf(vq, &len)))
+                free_buf(buf, can_sleep);
+}
+
 static void out_intr(struct virtqueue *vq)
 {
         struct port *port;
 
         port = find_port_by_vq(vq->vdev->priv, vq);
-        if (!port)
+        if (!port) {
+                flush_bufs(vq, false);
                 return;
+        }
 
         wake_up_interruptible(&port->waitqueue);
 }
@@ -1808,8 +1796,10 @@ static void in_intr(struct virtqueue *vq)
         unsigned long flags;
 
         port = find_port_by_vq(vq->vdev->priv, vq);
-        if (!port)
+        if (!port) {
+                flush_bufs(vq, false);
                 return;
+        }
 
         spin_lock_irqsave(&port->inbuf_lock, flags);
         port->inbuf = get_inbuf(port);
@@ -1984,24 +1974,54 @@ static const struct file_operations portdev_fops = {
 
 static void remove_vqs(struct ports_device *portdev)
 {
+        struct virtqueue *vq;
+
+        virtio_device_for_each_vq(portdev->vdev, vq) {
+                struct port_buffer *buf;
+
+                flush_bufs(vq, true);
+                while ((buf = virtqueue_detach_unused_buf(vq)))
+                        free_buf(buf, true);
+        }
         portdev->vdev->config->del_vqs(portdev->vdev);
         kfree(portdev->in_vqs);