From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andy Lutomirski Subject: [PATCH v4 5/6] virtio_mmio: Use the DMA API Date: Thu, 29 Oct 2015 18:09:50 -0700 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: In-Reply-To: References: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: linux-kernel@vger.kernel.org, "David S. Miller" , sparclinux@vger.kernel.org Cc: linux-s390 , Joerg Roedel , KVM , "Michael S. Tsirkin" , benh@kernel.crashing.org, Sebastian Ott , virtualization@lists.linux-foundation.org, Christian Borntraeger , Andy Lutomirski , Paolo Bonzini , dwmw2@infradead.org, Christoph Hellwig , Martin Schwidefsky List-Id: virtualization@lists.linuxfoundation.org This switches to vring_create_virtqueue, simplifying the driver and adding DMA API support. Signed-off-by: Andy Lutomirski --- drivers/virtio/virtio_mmio.c | 67 ++++++++++---------------------------------- 1 file changed, 15 insertions(+), 52 deletions(-) diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index f499d9da7237..2b9fab52a3cb 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -99,12 +99,6 @@ struct virtio_mmio_vq_info { /* the actual virtqueue */ struct virtqueue *vq; - /* the number of entries in the queue */ - unsigned int num; - - /* the virtual address of the ring queue */ - void *queue; - /* the list node for the virtqueues list */ struct list_head node; }; @@ -322,15 +316,13 @@ 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, size; + 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); - vring_del_virtqueue(vq); - /* Select and deactivate the queue */ writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL); if (vm_dev->version == 1) { @@ -340,8 +332,8 @@ static void vm_del_vq(struct virtqueue *vq) WARN_ON(readl(vm_dev->base + VIRTIO_MMIO_QUEUE_READY)); } - size = PAGE_ALIGN(vring_size(info->num, VIRTIO_MMIO_VRING_ALIGN)); - free_pages_exact(info->queue, size); + vring_del_virtqueue(vq); + kfree(info); } @@ -356,8 +348,6 @@ static void vm_del_vqs(struct virtio_device *vdev) free_irq(platform_get_irq(vm_dev->pdev, 0), vm_dev); } - - static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index, void (*callback)(struct virtqueue *vq), const char *name) @@ -365,7 +355,8 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index, struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); struct virtio_mmio_vq_info *info; struct virtqueue *vq; - unsigned long flags, size; + unsigned long flags; + unsigned int num; int err; if (!name) @@ -388,66 +379,40 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index, goto error_kmalloc; } - /* Allocate pages for the queue - start with a queue as big as - * possible (limited by maximum size allowed by device), drop down - * to a minimal size, just big enough to fit descriptor table - * and two rings (which makes it "alignment_size * 2") - */ - info->num = readl(vm_dev->base + VIRTIO_MMIO_QUEUE_NUM_MAX); - - /* If the device reports a 0 entry queue, we won't be able to - * use it to perform I/O, and vring_new_virtqueue() can't create - * empty queues anyway, so don't bother to set up the device. - */ - if (info->num == 0) { + num = readl(vm_dev->base + VIRTIO_MMIO_QUEUE_NUM_MAX); + if (num == 0) { err = -ENOENT; - goto error_alloc_pages; - } - - while (1) { - size = PAGE_ALIGN(vring_size(info->num, - VIRTIO_MMIO_VRING_ALIGN)); - /* Did the last iter shrink the queue below minimum size? */ - if (size < VIRTIO_MMIO_VRING_ALIGN * 2) { - err = -ENOMEM; - goto error_alloc_pages; - } - - info->queue = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO); - if (info->queue) - break; - - info->num /= 2; + goto error_new_virtqueue; } /* Create the vring */ - vq = vring_new_virtqueue(index, info->num, VIRTIO_MMIO_VRING_ALIGN, vdev, - true, info->queue, vm_notify, callback, name); + vq = vring_create_virtqueue(index, num, VIRTIO_MMIO_VRING_ALIGN, vdev, + true, true, vm_notify, callback, name); if (!vq) { err = -ENOMEM; goto error_new_virtqueue; } /* Activate the queue */ - writel(info->num, vm_dev->base + VIRTIO_MMIO_QUEUE_NUM); + writel(virtqueue_get_vring_size(vq), vm_dev->base + VIRTIO_MMIO_QUEUE_NUM); if (vm_dev->version == 1) { writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_QUEUE_ALIGN); - writel(virt_to_phys(info->queue) >> PAGE_SHIFT, + writel(virtqueue_get_desc_addr(vq) >> PAGE_SHIFT, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); } else { u64 addr; - addr = virt_to_phys(info->queue); + addr = virtqueue_get_desc_addr(vq); writel((u32)addr, vm_dev->base + VIRTIO_MMIO_QUEUE_DESC_LOW); writel((u32)(addr >> 32), vm_dev->base + VIRTIO_MMIO_QUEUE_DESC_HIGH); - addr = virt_to_phys(virtqueue_get_avail(vq)); + addr = virtqueue_get_avail_addr(vq); writel((u32)addr, vm_dev->base + VIRTIO_MMIO_QUEUE_AVAIL_LOW); writel((u32)(addr >> 32), vm_dev->base + VIRTIO_MMIO_QUEUE_AVAIL_HIGH); - addr = virt_to_phys(virtqueue_get_used(vq)); + addr = virtqueue_get_used_addr(vq); writel((u32)addr, vm_dev->base + VIRTIO_MMIO_QUEUE_USED_LOW); writel((u32)(addr >> 32), vm_dev->base + VIRTIO_MMIO_QUEUE_USED_HIGH); @@ -471,8 +436,6 @@ error_new_virtqueue: writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_READY); WARN_ON(readl(vm_dev->base + VIRTIO_MMIO_QUEUE_READY)); } - free_pages_exact(info->queue, size); -error_alloc_pages: kfree(info); error_kmalloc: error_available: -- 2.4.3