Commit 22af48cf authored by Xie Yongji's avatar Xie Yongji Committed by Michael S. Tsirkin
Browse files

vdpa: factor out vhost_vdpa_pa_map() and vhost_vdpa_pa_unmap() 



The upcoming patch is going to support VA mapping/unmapping.
So let's factor out the logic of PA mapping/unmapping firstly
to make the code more readable.

Suggested-by: default avatarJason Wang <jasowang@redhat.com>
Signed-off-by: default avatarXie Yongji <xieyongji@bytedance.com>
Acked-by: default avatarJason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210831103634.33-10-xieyongji@bytedance.com


Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent c10fb945

drivers/vhost/vdpa.c

+35 −20
Original line number Diff line number Diff line
@@ -504,7 +504,7 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep, 
	return r;

}



static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)

static void vhost_vdpa_pa_unmap(struct vhost_vdpa *v, u64 start, u64 last)

{

	struct vhost_dev *dev = &v->vdev;

	struct vhost_iotlb *iotlb = dev->iotlb;
@@ -526,6 +526,11 @@ static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last) 
	}

}



static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)

{

	return vhost_vdpa_pa_unmap(v, start, last);

}



static void vhost_vdpa_iotlb_free(struct vhost_vdpa *v)

{

	struct vhost_dev *dev = &v->vdev;
@@ -606,38 +611,28 @@ static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size) 
	}

}



static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,

					   struct vhost_iotlb_msg *msg)

static int vhost_vdpa_pa_map(struct vhost_vdpa *v,

			     u64 iova, u64 size, u64 uaddr, u32 perm)

{

	struct vhost_dev *dev = &v->vdev;

	struct vhost_iotlb *iotlb = dev->iotlb;

	struct page **page_list;

	unsigned long list_size = PAGE_SIZE / sizeof(struct page *);

	unsigned int gup_flags = FOLL_LONGTERM;

	unsigned long npages, cur_base, map_pfn, last_pfn = 0;

	unsigned long lock_limit, sz2pin, nchunks, i;

	u64 iova = msg->iova;

	u64 start = iova;

	long pinned;

	int ret = 0;



	if (msg->iova < v->range.first || !msg->size ||

	    msg->iova > U64_MAX - msg->size + 1 ||

	    msg->iova + msg->size - 1 > v->range.last)

		return -EINVAL;



	if (vhost_iotlb_itree_first(iotlb, msg->iova,

				    msg->iova + msg->size - 1))

		return -EEXIST;



	/* Limit the use of memory for bookkeeping */

	page_list = (struct page **) __get_free_page(GFP_KERNEL);

	if (!page_list)

		return -ENOMEM;



	if (msg->perm & VHOST_ACCESS_WO)

	if (perm & VHOST_ACCESS_WO)

		gup_flags |= FOLL_WRITE;



	npages = PFN_UP(msg->size + (iova & ~PAGE_MASK));

	npages = PFN_UP(size + (iova & ~PAGE_MASK));

	if (!npages) {

		ret = -EINVAL;

		goto free;
@@ -651,7 +646,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v, 
		goto unlock;

	}



	cur_base = msg->uaddr & PAGE_MASK;

	cur_base = uaddr & PAGE_MASK;

	iova &= PAGE_MASK;

	nchunks = 0;
@@ -682,7 +677,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v, 
				csize = PFN_PHYS(last_pfn - map_pfn + 1);

				ret = vhost_vdpa_map(v, iova, csize,

						     PFN_PHYS(map_pfn),

						     msg->perm);

						     perm);

				if (ret) {

					/*

					 * Unpin the pages that are left unmapped
@@ -711,7 +706,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v, 


	/* Pin the rest chunk */

	ret = vhost_vdpa_map(v, iova, PFN_PHYS(last_pfn - map_pfn + 1),

			     PFN_PHYS(map_pfn), msg->perm);

			     PFN_PHYS(map_pfn), perm);

out:

	if (ret) {

		if (nchunks) {
@@ -730,13 +725,33 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v, 
			for (pfn = map_pfn; pfn <= last_pfn; pfn++)

				unpin_user_page(pfn_to_page(pfn));

		}

		vhost_vdpa_unmap(v, msg->iova, msg->size);

		vhost_vdpa_unmap(v, start, size);

	}

unlock:

	mmap_read_unlock(dev->mm);

free:

	free_page((unsigned long)page_list);

	return ret;



}



static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,

					   struct vhost_iotlb_msg *msg)

{

	struct vhost_dev *dev = &v->vdev;

	struct vhost_iotlb *iotlb = dev->iotlb;



	if (msg->iova < v->range.first || !msg->size ||

	    msg->iova > U64_MAX - msg->size + 1 ||

	    msg->iova + msg->size - 1 > v->range.last)

		return -EINVAL;



	if (vhost_iotlb_itree_first(iotlb, msg->iova,

				    msg->iova + msg->size - 1))

		return -EEXIST;



	return vhost_vdpa_pa_map(v, msg->iova, msg->size, msg->uaddr,

				 msg->perm);

}



static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev,