Commit 3d569879 authored by Gautam Dawar's avatar Gautam Dawar Committed by Michael S. Tsirkin
Browse files

vhost-vdpa: introduce asid based IOTLB 



This patch converts the vhost-vDPA device to support multiple IOTLBs
tagged via ASID via hlist. This will be used for supporting multiple
address spaces in the following patches.

Signed-off-by: default avatarJason Wang <jasowang@redhat.com>
Signed-off-by: default avatarGautam Dawar <gdawar@xilinx.com>
Message-Id: <20220330180436.24644-11-gdawar@xilinx.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent 91233ad7

drivers/vhost/vdpa.c

+72 −25
Original line number Diff line number Diff line
@@ -33,13 +33,21 @@ enum { 


#define VHOST_VDPA_DEV_MAX (1U << MINORBITS)



#define VHOST_VDPA_IOTLB_BUCKETS 16



struct vhost_vdpa_as {

	struct hlist_node hash_link;

	struct vhost_iotlb iotlb;

	u32 id;

};



struct vhost_vdpa {

	struct vhost_dev vdev;

	struct iommu_domain *domain;

	struct vhost_virtqueue *vqs;

	struct completion completion;

	struct vdpa_device *vdpa;

	struct vhost_iotlb *iotlb;

	struct hlist_head as[VHOST_VDPA_IOTLB_BUCKETS];

	struct device dev;

	struct cdev cdev;

	atomic_t opened;
@@ -55,6 +63,51 @@ static DEFINE_IDA(vhost_vdpa_ida); 


static dev_t vhost_vdpa_major;



static struct vhost_vdpa_as *asid_to_as(struct vhost_vdpa *v, u32 asid)

{

	struct hlist_head *head = &v->as[asid % VHOST_VDPA_IOTLB_BUCKETS];

	struct vhost_vdpa_as *as;



	hlist_for_each_entry(as, head, hash_link)

		if (as->id == asid)

			return as;



	return NULL;

}



static struct vhost_vdpa_as *vhost_vdpa_alloc_as(struct vhost_vdpa *v, u32 asid)

{

	struct hlist_head *head = &v->as[asid % VHOST_VDPA_IOTLB_BUCKETS];

	struct vhost_vdpa_as *as;



	if (asid_to_as(v, asid))

		return NULL;



	as = kmalloc(sizeof(*as), GFP_KERNEL);

	if (!as)

		return NULL;



	vhost_iotlb_init(&as->iotlb, 0, 0);

	as->id = asid;

	hlist_add_head(&as->hash_link, head);



	return as;

}



static int vhost_vdpa_remove_as(struct vhost_vdpa *v, u32 asid)

{

	struct vhost_vdpa_as *as = asid_to_as(v, asid);



	if (!as)

		return -EINVAL;



	hlist_del(&as->hash_link);

	vhost_iotlb_reset(&as->iotlb);

	kfree(as);



	return 0;

}



static void handle_vq_kick(struct vhost_work *work)

{

	struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
@@ -588,15 +641,6 @@ static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, 
	return vhost_vdpa_pa_unmap(v, iotlb, start, last);

}



static void vhost_vdpa_iotlb_free(struct vhost_vdpa *v)

{

	struct vhost_iotlb *iotlb = v->iotlb;



	vhost_vdpa_iotlb_unmap(v, iotlb, 0ULL, 0ULL - 1);

	kfree(v->iotlb);

	v->iotlb = NULL;

}



static int perm_to_iommu_flags(u32 perm)

{

	int flags = 0;
@@ -876,7 +920,8 @@ static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev, u32 asid, 
	struct vhost_vdpa *v = container_of(dev, struct vhost_vdpa, vdev);

	struct vdpa_device *vdpa = v->vdpa;

	const struct vdpa_config_ops *ops = vdpa->config;

	struct vhost_iotlb *iotlb = v->iotlb;

	struct vhost_vdpa_as *as = asid_to_as(v, 0);

	struct vhost_iotlb *iotlb = &as->iotlb;

	int r = 0;



	if (asid != 0)
@@ -987,6 +1032,13 @@ static void vhost_vdpa_set_iova_range(struct vhost_vdpa *v) 
	}

}



static void vhost_vdpa_cleanup(struct vhost_vdpa *v)

{

	vhost_dev_cleanup(&v->vdev);

	kfree(v->vdev.vqs);

	vhost_vdpa_remove_as(v, 0);

}



static int vhost_vdpa_open(struct inode *inode, struct file *filep)

{

	struct vhost_vdpa *v;
@@ -1020,15 +1072,12 @@ static int vhost_vdpa_open(struct inode *inode, struct file *filep) 
	vhost_dev_init(dev, vqs, nvqs, 0, 0, 0, false,

		       vhost_vdpa_process_iotlb_msg);



	v->iotlb = vhost_iotlb_alloc(0, 0);

	if (!v->iotlb) {

		r = -ENOMEM;

		goto err_init_iotlb;

	}

	if (!vhost_vdpa_alloc_as(v, 0))

		goto err_alloc_as;



	r = vhost_vdpa_alloc_domain(v);

	if (r)

		goto err_alloc_domain;

		goto err_alloc_as;



	vhost_vdpa_set_iova_range(v);
@@ -1036,11 +1085,8 @@ static int vhost_vdpa_open(struct inode *inode, struct file *filep) 


	return 0;



err_alloc_domain:

	vhost_vdpa_iotlb_free(v);

err_init_iotlb:

	vhost_dev_cleanup(&v->vdev);

	kfree(vqs);

err_alloc_as:

	vhost_vdpa_cleanup(v);

err:

	atomic_dec(&v->opened);

	return r;
@@ -1064,11 +1110,9 @@ static int vhost_vdpa_release(struct inode *inode, struct file *filep) 
	vhost_vdpa_clean_irq(v);

	vhost_vdpa_reset(v);

	vhost_dev_stop(&v->vdev);

	vhost_vdpa_iotlb_free(v);

	vhost_vdpa_free_domain(v);

	vhost_vdpa_config_put(v);

	vhost_dev_cleanup(&v->vdev);

	kfree(v->vdev.vqs);

	mutex_unlock(&d->mutex);



	atomic_dec(&v->opened);
@@ -1164,7 +1208,7 @@ static int vhost_vdpa_probe(struct vdpa_device *vdpa) 
	const struct vdpa_config_ops *ops = vdpa->config;

	struct vhost_vdpa *v;

	int minor;

	int r;

	int i, r;



	/* Only support 1 address space and 1 groups */

	if (vdpa->ngroups != 1 || vdpa->nas != 1)
@@ -1212,6 +1256,9 @@ static int vhost_vdpa_probe(struct vdpa_device *vdpa) 
	init_completion(&v->completion);

	vdpa_set_drvdata(vdpa, v);



	for (i = 0; i < VHOST_VDPA_IOTLB_BUCKETS; i++)

		INIT_HLIST_HEAD(&v->as[i]);



	return 0;



err: