Commit d0f8fce9 authored by jiangdongxu's avatar jiangdongxu
Browse files

vhost-vdpa: Allow transparent MSI IOV 

virt inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I86ITO



----------------------------------------------------------------------

When attach dma_dev to iommu domain, check the device's
reserved regions and test whether the IOMMU translates
MSI transactions. If yes, we initialize an IOVA allocator
through the iommu_get_msi_cookie API. This will allow the
MSI IOVAs to be transparently allocated on MSI controller's
compose().

Signed-off-by: default avatarjiangdongxu <jiangdongxu1@huawei.com>
parent 8049ef97

drivers/vhost/vdpa.c

+57 −3
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ 
#include <linux/vdpa.h>

#include <linux/nospec.h>

#include <linux/vhost.h>

#include <linux/dma-iommu.h>



#include "vhost.h"
@@ -49,6 +50,7 @@ struct vhost_vdpa { 
	struct completion completion;

	struct vdpa_device *vdpa;

	struct hlist_head as[VHOST_VDPA_IOTLB_BUCKETS];

	struct vhost_iotlb resv_iotlb;

	struct device dev;

	struct cdev cdev;

	atomic_t opened;
@@ -1251,6 +1253,10 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v, 
	    msg->iova + msg->size - 1 > v->range.last)

		return -EINVAL;



	if (vhost_iotlb_itree_first(&v->resv_iotlb, msg->iova,

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

		return -EINVAL;



	if (vhost_iotlb_itree_first(iotlb, msg->iova,

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

		return -EEXIST;
@@ -1339,6 +1345,46 @@ static ssize_t vhost_vdpa_chr_write_iter(struct kiocb *iocb, 
	return vhost_chr_write_iter(dev, from);

}



static int vhost_vdpa_resv_iommu_region(struct iommu_domain *domain, struct device *dma_dev,

	struct vhost_iotlb *resv_iotlb)

{

	struct list_head dev_resv_regions;

	phys_addr_t resv_msi_base = 0;

	struct iommu_resv_region *region;

	int ret = 0;

	bool with_sw_msi = false;

	bool with_hw_msi = false;



	INIT_LIST_HEAD(&dev_resv_regions);

	iommu_get_resv_regions(dma_dev, &dev_resv_regions);



	list_for_each_entry(region, &dev_resv_regions, list) {

		ret = vhost_iotlb_add_range_ctx(resv_iotlb, region->start,

						region->start + region->length - 1,

						0, 0, NULL);

		if (ret) {

			vhost_iotlb_reset(resv_iotlb);

			break;

		}



		if (region->type == IOMMU_RESV_MSI)

			with_hw_msi = true;



		if (region->type == IOMMU_RESV_SW_MSI) {

			resv_msi_base = region->start;

			with_sw_msi = true;

		}



	}



	if (!ret && !with_hw_msi && with_sw_msi)

		ret = iommu_get_msi_cookie(domain, resv_msi_base);



	iommu_put_resv_regions(dma_dev, &dev_resv_regions);



	return ret;

}



static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v)

{

	struct vdpa_device *vdpa = v->vdpa;
@@ -1364,11 +1410,16 @@ static int vhost_vdpa_alloc_domain(struct vhost_vdpa *v) 


	ret = iommu_attach_device(v->domain, dma_dev);

	if (ret)

		goto err_attach;

		goto err_alloc_domain;



	return 0;

	ret = vhost_vdpa_resv_iommu_region(v->domain, dma_dev, &v->resv_iotlb);

	if (ret)

		goto err_attach_device;



err_attach:

	return 0;

err_attach_device:

	iommu_detach_device(v->domain, dma_dev);

err_alloc_domain:

	iommu_domain_free(v->domain);

	v->domain = NULL;

	return ret;
@@ -1495,6 +1546,7 @@ static int vhost_vdpa_release(struct inode *inode, struct file *filep) 
	vhost_vdpa_unbind_mm(v);

	vhost_vdpa_config_put(v);

	vhost_vdpa_cleanup(v);

	vhost_iotlb_reset(&v->resv_iotlb);

	mutex_unlock(&d->mutex);



	atomic_dec(&v->opened);
@@ -1627,6 +1679,8 @@ static int vhost_vdpa_probe(struct vdpa_device *vdpa) 
		goto err;

	}



	vhost_iotlb_init(&v->resv_iotlb, 0, 0);



	r = dev_set_name(&v->dev, "vhost-vdpa-%u", minor);

	if (r)

		goto err;