[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <f66b7ee2da7b7bb357fe17d319ec0932451ba5bf.1446162273.git.luto@kernel.org>
Date: Thu, 29 Oct 2015 18:09:50 -0700
From: Andy Lutomirski <luto@...nel.org>
To: linux-kernel@...r.kernel.org,
"David S. Miller" <davem@...emloft.net>, sparclinux@...r.kernel.org
Cc: Joerg Roedel <jroedel@...e.de>,
Christian Borntraeger <borntraeger@...ibm.com>,
Cornelia Huck <cornelia.huck@...ibm.com>,
Sebastian Ott <sebott@...ux.vnet.ibm.com>,
Paolo Bonzini <pbonzini@...hat.com>,
Christoph Hellwig <hch@....de>, benh@...nel.crashing.org,
KVM <kvm@...r.kernel.org>, dwmw2@...radead.org,
Martin Schwidefsky <schwidefsky@...ibm.com>,
linux-s390 <linux-s390@...r.kernel.org>,
"Michael S. Tsirkin" <mst@...hat.com>,
virtualization@...ts.linux-foundation.org,
Andy Lutomirski <luto@...nel.org>
Subject: [PATCH v4 5/6] virtio_mmio: Use the DMA API
This switches to vring_create_virtqueue, simplifying the driver and
adding DMA API support.
Signed-off-by: Andy Lutomirski <luto@...nel.org>
---
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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists