virtio-mmio: Remove virtqueue list from mmio device

The MMIO transport implementation creates a list of virtqueues for a
virtio device, while the same is already available in the struct
virtio_device.

Don't create a duplicate list, and use the other one instead.

While at it, fix the virtio_device_for_each_vq() macro to accept an
argument like "&vm_dev->vdev" (which currently fails to build).

Signed-off-by: Viresh Kumar <[e-mail]>
Message-Id: <3e56[e-mail]>
Signed-off-by: Michael S. Tsirkin <[e-mail]>
Acked-by: Jason Wang <[e-mail]>

drivers/virtio/virtio_mmio.c

···
 #include <linux/platform_device.h>
 #include <linux/pm.h>
 #include <linux/slab.h>
-#include <linux/spinlock.h>
 #include <linux/virtio.h>
 #include <linux/virtio_config.h>
 #include <uapi/linux/virtio_mmio.h>
···
 
 	void __iomem *base;
 	unsigned long version;
-
-	/* a list of queues so we can dispatch IRQs */
-	spinlock_t lock;
-	struct list_head virtqueues;
 };
-
-struct virtio_mmio_vq_info {
-	/* the actual virtqueue */
-	struct virtqueue *vq;
-
-	/* the list node for the virtqueues list */
-	struct list_head node;
-};
-
-
 
 /* Configuration interface */
 
···
 static irqreturn_t vm_interrupt(int irq, void *opaque)
 {
 	struct virtio_mmio_device *vm_dev = opaque;
-	struct virtio_mmio_vq_info *info;
+	struct virtqueue *vq;
 	unsigned long status;
-	unsigned long flags;
 	irqreturn_t ret = IRQ_NONE;
 
 	/* Read and acknowledge interrupts */
···
 	}
 
 	if (likely(status & VIRTIO_MMIO_INT_VRING)) {
-		spin_lock_irqsave(&vm_dev->lock, flags);
-		list_for_each_entry(info, &vm_dev->virtqueues, node)
-			ret |= vring_interrupt(irq, info->vq);
-		spin_unlock_irqrestore(&vm_dev->lock, flags);
+		virtio_device_for_each_vq(&vm_dev->vdev, vq)
+			ret |= vring_interrupt(irq, vq);
 	}
 
 	return ret;
···
 static void vm_del_vq(struct virtqueue *vq)
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev);
-	struct virtio_mmio_vq_info *info = vq->priv;
-	unsigned long flags;
 	unsigned int index = vq->index;
-
-	spin_lock_irqsave(&vm_dev->lock, flags);
-	list_del(&info->node);
-	spin_unlock_irqrestore(&vm_dev->lock, flags);
 
 	/* Select and deactivate the queue */
 	writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL);
···
 	}
 
 	vring_del_virtqueue(vq);
-
-	kfree(info);
 }
 
 static void vm_del_vqs(struct virtio_device *vdev)
···
 {
 	struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
 	bool (*notify)(struct virtqueue *vq);
-	struct virtio_mmio_vq_info *info;
 	struct virtqueue *vq;
-	unsigned long flags;
 	unsigned int num;
 	int err;
 
···
 			VIRTIO_MMIO_QUEUE_PFN : VIRTIO_MMIO_QUEUE_READY))) {
 		err = -ENOENT;
 		goto error_available;
-	}
-
-	/* Allocate and fill out our active queue description */
-	info = kmalloc(sizeof(*info), GFP_KERNEL);
-	if (!info) {
-		err = -ENOMEM;
-		goto error_kmalloc;
 	}
 
 	num = readl(vm_dev->base + VIRTIO_MMIO_QUEUE_NUM_MAX);
···
 		writel(1, vm_dev->base + VIRTIO_MMIO_QUEUE_READY);
 	}
 
-	vq->priv = info;
-	info->vq = vq;
-
-	spin_lock_irqsave(&vm_dev->lock, flags);
-	list_add(&info->node, &vm_dev->virtqueues);
-	spin_unlock_irqrestore(&vm_dev->lock, flags);
-
 	return vq;
 
 error_bad_pfn:
···
 		writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_READY);
 		WARN_ON(readl(vm_dev->base + VIRTIO_MMIO_QUEUE_READY));
 	}
-	kfree(info);
-error_kmalloc:
 error_available:
 	return ERR_PTR(err);
 }
···
 	vm_dev->vdev.dev.release = virtio_mmio_release_dev;
 	vm_dev->vdev.config = &virtio_mmio_config_ops;
 	vm_dev->pdev = pdev;
-	INIT_LIST_HEAD(&vm_dev->virtqueues);
-	spin_lock_init(&vm_dev->lock);
 
 	vm_dev->base = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(vm_dev->base)) {

include/linux/virtio.h

···
 size_t virtio_max_dma_size(const struct virtio_device *vdev);
 
 #define virtio_device_for_each_vq(vdev, vq) \
-	list_for_each_entry(vq, &vdev->vqs, list)
+	list_for_each_entry(vq, &(vdev)->vqs, list)
 
 /**
  * struct virtio_driver - operations for a virtio I/O driver