Re: [RFC PATCH 05/24] vhost-vdpa: passing iotlb to IOMMU mapping helpers

[Jason Wang <jasowang@redhat.com>]

On 2020/9/30 下午7:26, Eli Cohen wrote:
> On Thu, Sep 24, 2020 at 11:21:06AM +0800, Jason Wang wrote:
>> To prepare for the ASID support for vhost-vdpa, try to pass IOTLB
>> object to dma helpers.
> Maybe it's worth mentioning here that this patch does not change any
> functionality and is presented as a preparation for passing different
> iotlb's instead of using dev->iotlb


Right, let me add them in the next version.

Thanks


>
>> Signed-off-by: Jason Wang <jasowang@redhat.com>
>> ---
>>   drivers/vhost/vdpa.c | 40 ++++++++++++++++++++++------------------
>>   1 file changed, 22 insertions(+), 18 deletions(-)
>>
>> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
>> index 9c641274b9f3..74bef1c15a70 100644
>> --- a/drivers/vhost/vdpa.c
>> +++ b/drivers/vhost/vdpa.c
>> @@ -489,10 +489,11 @@ 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_iotlb_unmap(struct vhost_vdpa *v,
>> +				   struct vhost_iotlb *iotlb,
>> +				   u64 start, u64 last)
>>   {
>>   	struct vhost_dev *dev = &v->vdev;
>> -	struct vhost_iotlb *iotlb = dev->iotlb;
>>   	struct vhost_iotlb_map *map;
>>   	struct page *page;
>>   	unsigned long pfn, pinned;
>> @@ -514,8 +515,9 @@ static void vhost_vdpa_iotlb_unmap(struct vhost_vdpa *v, u64 start, u64 last)
>>   static void vhost_vdpa_iotlb_free(struct vhost_vdpa *v)
>>   {
>>   	struct vhost_dev *dev = &v->vdev;
>> +	struct vhost_iotlb *iotlb = dev->iotlb;
>>   
>> -	vhost_vdpa_iotlb_unmap(v, 0ULL, 0ULL - 1);
>> +	vhost_vdpa_iotlb_unmap(v, iotlb, 0ULL, 0ULL - 1);
>>   	kfree(dev->iotlb);
>>   	dev->iotlb = NULL;
>>   }
>> @@ -542,15 +544,14 @@ static int perm_to_iommu_flags(u32 perm)
>>   	return flags | IOMMU_CACHE;
>>   }
>>   
>> -static int vhost_vdpa_map(struct vhost_vdpa *v,
>> +static int vhost_vdpa_map(struct vhost_vdpa *v, struct vhost_iotlb *iotlb,
>>   			  u64 iova, u64 size, u64 pa, u32 perm)
>>   {
>> -	struct vhost_dev *dev = &v->vdev;
>>   	struct vdpa_device *vdpa = v->vdpa;
>>   	const struct vdpa_config_ops *ops = vdpa->config;
>>   	int r = 0;
>>   
>> -	r = vhost_iotlb_add_range(dev->iotlb, iova, iova + size - 1,
>> +	r = vhost_iotlb_add_range(iotlb, iova, iova + size - 1,
>>   				  pa, perm);
>>   	if (r)
>>   		return r;
>> @@ -559,7 +560,7 @@ static int vhost_vdpa_map(struct vhost_vdpa *v,
>>   		r = ops->dma_map(vdpa, iova, size, pa, perm);
>>   	} else if (ops->set_map) {
>>   		if (!v->in_batch)
>> -			r = ops->set_map(vdpa, dev->iotlb);
>> +			r = ops->set_map(vdpa, iotlb);
>>   	} else {
>>   		r = iommu_map(v->domain, iova, pa, size,
>>   			      perm_to_iommu_flags(perm));
>> @@ -568,29 +569,30 @@ static int vhost_vdpa_map(struct vhost_vdpa *v,
>>   	return r;
>>   }
>>   
>> -static void vhost_vdpa_unmap(struct vhost_vdpa *v, u64 iova, u64 size)
>> +static void vhost_vdpa_unmap(struct vhost_vdpa *v,
>> +			     struct vhost_iotlb *iotlb,
>> +			     u64 iova, u64 size)
>>   {
>> -	struct vhost_dev *dev = &v->vdev;
>>   	struct vdpa_device *vdpa = v->vdpa;
>>   	const struct vdpa_config_ops *ops = vdpa->config;
>>   
>> -	vhost_vdpa_iotlb_unmap(v, iova, iova + size - 1);
>> +	vhost_vdpa_iotlb_unmap(v, iotlb, iova, iova + size - 1);
>>   
>>   	if (ops->dma_map) {
>>   		ops->dma_unmap(vdpa, iova, size);
>>   	} else if (ops->set_map) {
>>   		if (!v->in_batch)
>> -			ops->set_map(vdpa, dev->iotlb);
>> +			ops->set_map(vdpa, iotlb);
>>   	} else {
>>   		iommu_unmap(v->domain, iova, size);
>>   	}
>>   }
>>   
>>   static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
>> +					   struct vhost_iotlb *iotlb,
>>   					   struct vhost_iotlb_msg *msg)
>>   {
>>   	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;
>> @@ -644,7 +646,7 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
>>   			if (last_pfn && (this_pfn != last_pfn + 1)) {
>>   				/* Pin a contiguous chunk of memory */
>>   				csize = (last_pfn - map_pfn + 1) << PAGE_SHIFT;
>> -				if (vhost_vdpa_map(v, iova, csize,
>> +				if (vhost_vdpa_map(v, iotlb, iova, csize,
>>   						   map_pfn << PAGE_SHIFT,
>>   						   msg->perm))
>>   					goto out;
>> @@ -660,11 +662,12 @@ static int vhost_vdpa_process_iotlb_update(struct vhost_vdpa *v,
>>   	}
>>   
>>   	/* Pin the rest chunk */
>> -	ret = vhost_vdpa_map(v, iova, (last_pfn - map_pfn + 1) << PAGE_SHIFT,
>> +	ret = vhost_vdpa_map(v, iotlb, iova,
>> +			     (last_pfn - map_pfn + 1) << PAGE_SHIFT,
>>   			     map_pfn << PAGE_SHIFT, msg->perm);
>>   out:
>>   	if (ret) {
>> -		vhost_vdpa_unmap(v, msg->iova, msg->size);
>> +		vhost_vdpa_unmap(v, iotlb, msg->iova, msg->size);
>>   		atomic64_sub(npages, &dev->mm->pinned_vm);
>>   	}
>>   	mmap_read_unlock(dev->mm);
>> @@ -678,6 +681,7 @@ static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev,
>>   	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 = dev->iotlb;
>>   	int r = 0;
>>   
>>   	r = vhost_dev_check_owner(dev);
>> @@ -686,17 +690,17 @@ static int vhost_vdpa_process_iotlb_msg(struct vhost_dev *dev,
>>   
>>   	switch (msg->type) {
>>   	case VHOST_IOTLB_UPDATE:
>> -		r = vhost_vdpa_process_iotlb_update(v, msg);
>> +		r = vhost_vdpa_process_iotlb_update(v, iotlb, msg);
>>   		break;
>>   	case VHOST_IOTLB_INVALIDATE:
>> -		vhost_vdpa_unmap(v, msg->iova, msg->size);
>> +		vhost_vdpa_unmap(v, iotlb, msg->iova, msg->size);
>>   		break;
>>   	case VHOST_IOTLB_BATCH_BEGIN:
>>   		v->in_batch = true;
>>   		break;
>>   	case VHOST_IOTLB_BATCH_END:
>>   		if (v->in_batch && ops->set_map)
>> -			ops->set_map(vdpa, dev->iotlb);
>> +			ops->set_map(vdpa, iotlb);
>>   		v->in_batch = false;
>>   		break;
>>   	default:
>> -- 
>> 2.20.1
>>