diff mbox series

[v3,01/14] vfio/type1: Refactor vfio_iommu_type1_ioctl()

Message ID 1592988927-48009-2-git-send-email-yi.l.liu@intel.com (mailing list archive)
State New, archived
Headers show
Series vfio: expose virtual Shared Virtual Addressing to VMs | expand

Commit Message

Yi Liu June 24, 2020, 8:55 a.m. UTC 
This patch refactors the vfio_iommu_type1_ioctl() to use switch instead of
if-else, and each cmd got a helper function.

Cc: Kevin Tian <kevin.tian@intel.com>
CC: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Lu Baolu <baolu.lu@linux.intel.com>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
---
 drivers/vfio/vfio_iommu_type1.c | 392 ++++++++++++++++++++++------------------
 1 file changed, 213 insertions(+), 179 deletions(-)

Comments

Alex Williamson July 2, 2020, 9:21 p.m. UTC | #1 
On Wed, 24 Jun 2020 01:55:14 -0700
Liu Yi L <yi.l.liu@intel.com> wrote:

> This patch refactors the vfio_iommu_type1_ioctl() to use switch instead of
> if-else, and each cmd got a helper function.
> 
> Cc: Kevin Tian <kevin.tian@intel.com>
> CC: Jacob Pan <jacob.jun.pan@linux.intel.com>
> Cc: Alex Williamson <alex.williamson@redhat.com>
> Cc: Eric Auger <eric.auger@redhat.com>
> Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
> Cc: Joerg Roedel <joro@8bytes.org>
> Cc: Lu Baolu <baolu.lu@linux.intel.com>
> Suggested-by: Christoph Hellwig <hch@infradead.org>
> Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
> ---
>  drivers/vfio/vfio_iommu_type1.c | 392 ++++++++++++++++++++++------------------
>  1 file changed, 213 insertions(+), 179 deletions(-)

I can go ahead and grab this one for my v5.9 next branch.  Thanks,

Alex
 
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 5e556ac..7accb59 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -2453,6 +2453,23 @@ static int vfio_domains_have_iommu_cache(struct vfio_iommu *iommu)
>  	return ret;
>  }
>  
> +static int vfio_iommu_type1_check_extension(struct vfio_iommu *iommu,
> +					    unsigned long arg)
> +{
> +	switch (arg) {
> +	case VFIO_TYPE1_IOMMU:
> +	case VFIO_TYPE1v2_IOMMU:
> +	case VFIO_TYPE1_NESTING_IOMMU:
> +		return 1;
> +	case VFIO_DMA_CC_IOMMU:
> +		if (!iommu)
> +			return 0;
> +		return vfio_domains_have_iommu_cache(iommu);
> +	default:
> +		return 0;
> +	}
> +}
> +
>  static int vfio_iommu_iova_add_cap(struct vfio_info_cap *caps,
>  		 struct vfio_iommu_type1_info_cap_iova_range *cap_iovas,
>  		 size_t size)
> @@ -2529,238 +2546,255 @@ static int vfio_iommu_migration_build_caps(struct vfio_iommu *iommu,
>  	return vfio_info_add_capability(caps, &cap_mig.header, sizeof(cap_mig));
>  }
>  
> -static long vfio_iommu_type1_ioctl(void *iommu_data,
> -				   unsigned int cmd, unsigned long arg)
> +static int vfio_iommu_type1_get_info(struct vfio_iommu *iommu,
> +				     unsigned long arg)
>  {
> -	struct vfio_iommu *iommu = iommu_data;
> +	struct vfio_iommu_type1_info info;
>  	unsigned long minsz;
> +	struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
> +	unsigned long capsz;
> +	int ret;
>  
> -	if (cmd == VFIO_CHECK_EXTENSION) {
> -		switch (arg) {
> -		case VFIO_TYPE1_IOMMU:
> -		case VFIO_TYPE1v2_IOMMU:
> -		case VFIO_TYPE1_NESTING_IOMMU:
> -			return 1;
> -		case VFIO_DMA_CC_IOMMU:
> -			if (!iommu)
> -				return 0;
> -			return vfio_domains_have_iommu_cache(iommu);
> -		default:
> -			return 0;
> -		}
> -	} else if (cmd == VFIO_IOMMU_GET_INFO) {
> -		struct vfio_iommu_type1_info info;
> -		struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
> -		unsigned long capsz;
> -		int ret;
> -
> -		minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes);
> +	minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes);
>  
> -		/* For backward compatibility, cannot require this */
> -		capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset);
> +	/* For backward compatibility, cannot require this */
> +	capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset);
>  
> -		if (copy_from_user(&info, (void __user *)arg, minsz))
> -			return -EFAULT;
> +	if (copy_from_user(&info, (void __user *)arg, minsz))
> +		return -EFAULT;
>  
> -		if (info.argsz < minsz)
> -			return -EINVAL;
> +	if (info.argsz < minsz)
> +		return -EINVAL;
>  
> -		if (info.argsz >= capsz) {
> -			minsz = capsz;
> -			info.cap_offset = 0; /* output, no-recopy necessary */
> -		}
> +	if (info.argsz >= capsz) {
> +		minsz = capsz;
> +		info.cap_offset = 0; /* output, no-recopy necessary */
> +	}
>  
> -		mutex_lock(&iommu->lock);
> -		info.flags = VFIO_IOMMU_INFO_PGSIZES;
> +	mutex_lock(&iommu->lock);
> +	info.flags = VFIO_IOMMU_INFO_PGSIZES;
>  
> -		info.iova_pgsizes = iommu->pgsize_bitmap;
> +	info.iova_pgsizes = iommu->pgsize_bitmap;
>  
> -		ret = vfio_iommu_migration_build_caps(iommu, &caps);
> +	ret = vfio_iommu_migration_build_caps(iommu, &caps);
>  
> -		if (!ret)
> -			ret = vfio_iommu_iova_build_caps(iommu, &caps);
> +	if (!ret)
> +		ret = vfio_iommu_iova_build_caps(iommu, &caps);
>  
> -		mutex_unlock(&iommu->lock);
> +	mutex_unlock(&iommu->lock);
>  
> -		if (ret)
> -			return ret;
> +	if (ret)
> +		return ret;
>  
> -		if (caps.size) {
> -			info.flags |= VFIO_IOMMU_INFO_CAPS;
> +	if (caps.size) {
> +		info.flags |= VFIO_IOMMU_INFO_CAPS;
>  
> -			if (info.argsz < sizeof(info) + caps.size) {
> -				info.argsz = sizeof(info) + caps.size;
> -			} else {
> -				vfio_info_cap_shift(&caps, sizeof(info));
> -				if (copy_to_user((void __user *)arg +
> -						sizeof(info), caps.buf,
> -						caps.size)) {
> -					kfree(caps.buf);
> -					return -EFAULT;
> -				}
> -				info.cap_offset = sizeof(info);
> +		if (info.argsz < sizeof(info) + caps.size) {
> +			info.argsz = sizeof(info) + caps.size;
> +		} else {
> +			vfio_info_cap_shift(&caps, sizeof(info));
> +			if (copy_to_user((void __user *)arg +
> +					sizeof(info), caps.buf,
> +					caps.size)) {
> +				kfree(caps.buf);
> +				return -EFAULT;
>  			}
> -
> -			kfree(caps.buf);
> +			info.cap_offset = sizeof(info);
>  		}
>  
> -		return copy_to_user((void __user *)arg, &info, minsz) ?
> -			-EFAULT : 0;
> +		kfree(caps.buf);
> +	}
>  
> -	} else if (cmd == VFIO_IOMMU_MAP_DMA) {
> -		struct vfio_iommu_type1_dma_map map;
> -		uint32_t mask = VFIO_DMA_MAP_FLAG_READ |
> -				VFIO_DMA_MAP_FLAG_WRITE;
> +	return copy_to_user((void __user *)arg, &info, minsz) ?
> +			-EFAULT : 0;
> +}
>  
> -		minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
> +static int vfio_iommu_type1_map_dma(struct vfio_iommu *iommu,
> +				    unsigned long arg)
> +{
> +	struct vfio_iommu_type1_dma_map map;
> +	unsigned long minsz;
> +	uint32_t mask = VFIO_DMA_MAP_FLAG_READ |
> +			VFIO_DMA_MAP_FLAG_WRITE;
>  
> -		if (copy_from_user(&map, (void __user *)arg, minsz))
> -			return -EFAULT;
> +	minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
>  
> -		if (map.argsz < minsz || map.flags & ~mask)
> -			return -EINVAL;
> +	if (copy_from_user(&map, (void __user *)arg, minsz))
> +		return -EFAULT;
>  
> -		return vfio_dma_do_map(iommu, &map);
> +	if (map.argsz < minsz || map.flags & ~mask)
> +		return -EINVAL;
>  
> -	} else if (cmd == VFIO_IOMMU_UNMAP_DMA) {
> -		struct vfio_iommu_type1_dma_unmap unmap;
> -		struct vfio_bitmap bitmap = { 0 };
> -		int ret;
> +	return vfio_dma_do_map(iommu, &map);
> +}
>  
> -		minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size);
> +static int vfio_iommu_type1_unmap_dma(struct vfio_iommu *iommu,
> +				      unsigned long arg)
> +{
> +	struct vfio_iommu_type1_dma_unmap unmap;
> +	struct vfio_bitmap bitmap = { 0 };
> +	unsigned long minsz;
> +	long ret;
>  
> -		if (copy_from_user(&unmap, (void __user *)arg, minsz))
> -			return -EFAULT;
> +	minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size);
>  
> -		if (unmap.argsz < minsz ||
> -		    unmap.flags & ~VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP)
> -			return -EINVAL;
> +	if (copy_from_user(&unmap, (void __user *)arg, minsz))
> +		return -EFAULT;
>  
> -		if (unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
> -			unsigned long pgshift;
> +	if (unmap.argsz < minsz ||
> +	    unmap.flags & ~VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP)
> +		return -EINVAL;
>  
> -			if (unmap.argsz < (minsz + sizeof(bitmap)))
> -				return -EINVAL;
> +	if (unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
> +		unsigned long pgshift;
>  
> -			if (copy_from_user(&bitmap,
> -					   (void __user *)(arg + minsz),
> -					   sizeof(bitmap)))
> -				return -EFAULT;
> +		if (unmap.argsz < (minsz + sizeof(bitmap)))
> +			return -EINVAL;
>  
> -			if (!access_ok((void __user *)bitmap.data, bitmap.size))
> -				return -EINVAL;
> +		if (copy_from_user(&bitmap,
> +				   (void __user *)(arg + minsz),
> +				   sizeof(bitmap)))
> +			return -EFAULT;
>  
> -			pgshift = __ffs(bitmap.pgsize);
> -			ret = verify_bitmap_size(unmap.size >> pgshift,
> -						 bitmap.size);
> -			if (ret)
> -				return ret;
> -		}
> +		if (!access_ok((void __user *)bitmap.data, bitmap.size))
> +			return -EINVAL;
>  
> -		ret = vfio_dma_do_unmap(iommu, &unmap, &bitmap);
> +		pgshift = __ffs(bitmap.pgsize);
> +		ret = verify_bitmap_size(unmap.size >> pgshift,
> +					 bitmap.size);
>  		if (ret)
>  			return ret;
> +	}
> +
> +	ret = vfio_dma_do_unmap(iommu, &unmap, &bitmap);
> +	if (ret)
> +		return ret;
>  
> -		return copy_to_user((void __user *)arg, &unmap, minsz) ?
> +	return copy_to_user((void __user *)arg, &unmap, minsz) ?
>  			-EFAULT : 0;
> -	} else if (cmd == VFIO_IOMMU_DIRTY_PAGES) {
> -		struct vfio_iommu_type1_dirty_bitmap dirty;
> -		uint32_t mask = VFIO_IOMMU_DIRTY_PAGES_FLAG_START |
> -				VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP |
> -				VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
> -		int ret = 0;
> +}
>  
> -		if (!iommu->v2)
> -			return -EACCES;
> +static int vfio_iommu_type1_dirty_pages(struct vfio_iommu *iommu,
> +					unsigned long arg)
> +{
> +	struct vfio_iommu_type1_dirty_bitmap dirty;
> +	uint32_t mask = VFIO_IOMMU_DIRTY_PAGES_FLAG_START |
> +			VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP |
> +			VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
> +	unsigned long minsz;
> +	int ret = 0;
>  
> -		minsz = offsetofend(struct vfio_iommu_type1_dirty_bitmap,
> -				    flags);
> +	if (!iommu->v2)
> +		return -EACCES;
>  
> -		if (copy_from_user(&dirty, (void __user *)arg, minsz))
> -			return -EFAULT;
> +	minsz = offsetofend(struct vfio_iommu_type1_dirty_bitmap,
> +			    flags);
>  
> -		if (dirty.argsz < minsz || dirty.flags & ~mask)
> -			return -EINVAL;
> +	if (copy_from_user(&dirty, (void __user *)arg, minsz))
> +		return -EFAULT;
> +
> +	if (dirty.argsz < minsz || dirty.flags & ~mask)
> +		return -EINVAL;
> +
> +	/* only one flag should be set at a time */
> +	if (__ffs(dirty.flags) != __fls(dirty.flags))
> +		return -EINVAL;
> +
> +	if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_START) {
> +		size_t pgsize;
>  
> -		/* only one flag should be set at a time */
> -		if (__ffs(dirty.flags) != __fls(dirty.flags))
> +		mutex_lock(&iommu->lock);
> +		pgsize = 1 << __ffs(iommu->pgsize_bitmap);
> +		if (!iommu->dirty_page_tracking) {
> +			ret = vfio_dma_bitmap_alloc_all(iommu, pgsize);
> +			if (!ret)
> +				iommu->dirty_page_tracking = true;
> +		}
> +		mutex_unlock(&iommu->lock);
> +		return ret;
> +	} else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP) {
> +		mutex_lock(&iommu->lock);
> +		if (iommu->dirty_page_tracking) {
> +			iommu->dirty_page_tracking = false;
> +			vfio_dma_bitmap_free_all(iommu);
> +		}
> +		mutex_unlock(&iommu->lock);
> +		return 0;
> +	} else if (dirty.flags &
> +			 VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP) {
> +		struct vfio_iommu_type1_dirty_bitmap_get range;
> +		unsigned long pgshift;
> +		size_t data_size = dirty.argsz - minsz;
> +		size_t iommu_pgsize;
> +
> +		if (!data_size || data_size < sizeof(range))
>  			return -EINVAL;
>  
> -		if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_START) {
> -			size_t pgsize;
> +		if (copy_from_user(&range, (void __user *)(arg + minsz),
> +				   sizeof(range)))
> +			return -EFAULT;
>  
> -			mutex_lock(&iommu->lock);
> -			pgsize = 1 << __ffs(iommu->pgsize_bitmap);
> -			if (!iommu->dirty_page_tracking) {
> -				ret = vfio_dma_bitmap_alloc_all(iommu, pgsize);
> -				if (!ret)
> -					iommu->dirty_page_tracking = true;
> -			}
> -			mutex_unlock(&iommu->lock);
> +		if (range.iova + range.size < range.iova)
> +			return -EINVAL;
> +		if (!access_ok((void __user *)range.bitmap.data,
> +			       range.bitmap.size))
> +			return -EINVAL;
> +
> +		pgshift = __ffs(range.bitmap.pgsize);
> +		ret = verify_bitmap_size(range.size >> pgshift,
> +					 range.bitmap.size);
> +		if (ret)
>  			return ret;
> -		} else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP) {
> -			mutex_lock(&iommu->lock);
> -			if (iommu->dirty_page_tracking) {
> -				iommu->dirty_page_tracking = false;
> -				vfio_dma_bitmap_free_all(iommu);
> -			}
> -			mutex_unlock(&iommu->lock);
> -			return 0;
> -		} else if (dirty.flags &
> -				 VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP) {
> -			struct vfio_iommu_type1_dirty_bitmap_get range;
> -			unsigned long pgshift;
> -			size_t data_size = dirty.argsz - minsz;
> -			size_t iommu_pgsize;
> -
> -			if (!data_size || data_size < sizeof(range))
> -				return -EINVAL;
> -
> -			if (copy_from_user(&range, (void __user *)(arg + minsz),
> -					   sizeof(range)))
> -				return -EFAULT;
>  
> -			if (range.iova + range.size < range.iova)
> -				return -EINVAL;
> -			if (!access_ok((void __user *)range.bitmap.data,
> -				       range.bitmap.size))
> -				return -EINVAL;
> +		mutex_lock(&iommu->lock);
>  
> -			pgshift = __ffs(range.bitmap.pgsize);
> -			ret = verify_bitmap_size(range.size >> pgshift,
> -						 range.bitmap.size);
> -			if (ret)
> -				return ret;
> +		iommu_pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
>  
> -			mutex_lock(&iommu->lock);
> +		/* allow only smallest supported pgsize */
> +		if (range.bitmap.pgsize != iommu_pgsize) {
> +			ret = -EINVAL;
> +			goto out_unlock;
> +		}
> +		if (range.iova & (iommu_pgsize - 1)) {
> +			ret = -EINVAL;
> +			goto out_unlock;
> +		}
> +		if (!range.size || range.size & (iommu_pgsize - 1)) {
> +			ret = -EINVAL;
> +			goto out_unlock;
> +		}
>  
> -			iommu_pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
> +		if (iommu->dirty_page_tracking)
> +			ret = vfio_iova_dirty_bitmap(range.bitmap.data,
> +					iommu, range.iova, range.size,
> +					range.bitmap.pgsize);
> +		else
> +			ret = -EINVAL;
> +out_unlock:
> +		mutex_unlock(&iommu->lock);
>  
> -			/* allow only smallest supported pgsize */
> -			if (range.bitmap.pgsize != iommu_pgsize) {
> -				ret = -EINVAL;
> -				goto out_unlock;
> -			}
> -			if (range.iova & (iommu_pgsize - 1)) {
> -				ret = -EINVAL;
> -				goto out_unlock;
> -			}
> -			if (!range.size || range.size & (iommu_pgsize - 1)) {
> -				ret = -EINVAL;
> -				goto out_unlock;
> -			}
> +		return ret;
> +	}
>  
> -			if (iommu->dirty_page_tracking)
> -				ret = vfio_iova_dirty_bitmap(range.bitmap.data,
> -						iommu, range.iova, range.size,
> -						range.bitmap.pgsize);
> -			else
> -				ret = -EINVAL;
> -out_unlock:
> -			mutex_unlock(&iommu->lock);
> +	return -EINVAL;
> +}
>  
> -			return ret;
> -		}
> +static long vfio_iommu_type1_ioctl(void *iommu_data,
> +				   unsigned int cmd, unsigned long arg)
> +{
> +	struct vfio_iommu *iommu = iommu_data;
> +
> +	switch (cmd) {
> +	case VFIO_CHECK_EXTENSION:
> +		return vfio_iommu_type1_check_extension(iommu, arg);
> +	case VFIO_IOMMU_GET_INFO:
> +		return vfio_iommu_type1_get_info(iommu, arg);
> +	case VFIO_IOMMU_MAP_DMA:
> +		return vfio_iommu_type1_map_dma(iommu, arg);
> +	case VFIO_IOMMU_UNMAP_DMA:
> +		return vfio_iommu_type1_unmap_dma(iommu, arg);
> +	case VFIO_IOMMU_DIRTY_PAGES:
> +		return vfio_iommu_type1_dirty_pages(iommu, arg);
>  	}
>  
>  	return -ENOTTY;
Yi Liu July 3, 2020, 3:46 a.m. UTC | #2 
> From: Alex Williamson <alex.williamson@redhat.com>
> Sent: Friday, July 3, 2020 5:21 AM
> To: Liu, Yi L <yi.l.liu@intel.com>
> 
> On Wed, 24 Jun 2020 01:55:14 -0700
> Liu Yi L <yi.l.liu@intel.com> wrote:
> 
> > This patch refactors the vfio_iommu_type1_ioctl() to use switch
> > instead of if-else, and each cmd got a helper function.
> >
> > Cc: Kevin Tian <kevin.tian@intel.com>
> > CC: Jacob Pan <jacob.jun.pan@linux.intel.com>
> > Cc: Alex Williamson <alex.williamson@redhat.com>
> > Cc: Eric Auger <eric.auger@redhat.com>
> > Cc: Jean-Philippe Brucker <jean-philippe@linaro.org>
> > Cc: Joerg Roedel <joro@8bytes.org>
> > Cc: Lu Baolu <baolu.lu@linux.intel.com>
> > Suggested-by: Christoph Hellwig <hch@infradead.org>
> > Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
> > ---
> >  drivers/vfio/vfio_iommu_type1.c | 392
> > ++++++++++++++++++++++------------------
> >  1 file changed, 213 insertions(+), 179 deletions(-)
> 
> I can go ahead and grab this one for my v5.9 next branch.  Thanks,

thanks, that would be great help. I'll monitor your next branch on github.

Regards,
Yi Liu

> Alex
> 
> > diff --git a/drivers/vfio/vfio_iommu_type1.c
> > b/drivers/vfio/vfio_iommu_type1.c index 5e556ac..7accb59 100644
> > --- a/drivers/vfio/vfio_iommu_type1.c
> > +++ b/drivers/vfio/vfio_iommu_type1.c
> > @@ -2453,6 +2453,23 @@ static int vfio_domains_have_iommu_cache(struct
> vfio_iommu *iommu)
> >  	return ret;
> >  }
> >
> > +static int vfio_iommu_type1_check_extension(struct vfio_iommu *iommu,
> > +					    unsigned long arg)
> > +{
> > +	switch (arg) {
> > +	case VFIO_TYPE1_IOMMU:
> > +	case VFIO_TYPE1v2_IOMMU:
> > +	case VFIO_TYPE1_NESTING_IOMMU:
> > +		return 1;
> > +	case VFIO_DMA_CC_IOMMU:
> > +		if (!iommu)
> > +			return 0;
> > +		return vfio_domains_have_iommu_cache(iommu);
> > +	default:
> > +		return 0;
> > +	}
> > +}
> > +
> >  static int vfio_iommu_iova_add_cap(struct vfio_info_cap *caps,
> >  		 struct vfio_iommu_type1_info_cap_iova_range *cap_iovas,
> >  		 size_t size)
> > @@ -2529,238 +2546,255 @@ static int
> vfio_iommu_migration_build_caps(struct vfio_iommu *iommu,
> >  	return vfio_info_add_capability(caps, &cap_mig.header,
> > sizeof(cap_mig));  }
> >
> > -static long vfio_iommu_type1_ioctl(void *iommu_data,
> > -				   unsigned int cmd, unsigned long arg)
> > +static int vfio_iommu_type1_get_info(struct vfio_iommu *iommu,
> > +				     unsigned long arg)
> >  {
> > -	struct vfio_iommu *iommu = iommu_data;
> > +	struct vfio_iommu_type1_info info;
> >  	unsigned long minsz;
> > +	struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
> > +	unsigned long capsz;
> > +	int ret;
> >
> > -	if (cmd == VFIO_CHECK_EXTENSION) {
> > -		switch (arg) {
> > -		case VFIO_TYPE1_IOMMU:
> > -		case VFIO_TYPE1v2_IOMMU:
> > -		case VFIO_TYPE1_NESTING_IOMMU:
> > -			return 1;
> > -		case VFIO_DMA_CC_IOMMU:
> > -			if (!iommu)
> > -				return 0;
> > -			return vfio_domains_have_iommu_cache(iommu);
> > -		default:
> > -			return 0;
> > -		}
> > -	} else if (cmd == VFIO_IOMMU_GET_INFO) {
> > -		struct vfio_iommu_type1_info info;
> > -		struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
> > -		unsigned long capsz;
> > -		int ret;
> > -
> > -		minsz = offsetofend(struct vfio_iommu_type1_info,
> iova_pgsizes);
> > +	minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes);
> >
> > -		/* For backward compatibility, cannot require this */
> > -		capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset);
> > +	/* For backward compatibility, cannot require this */
> > +	capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset);
> >
> > -		if (copy_from_user(&info, (void __user *)arg, minsz))
> > -			return -EFAULT;
> > +	if (copy_from_user(&info, (void __user *)arg, minsz))
> > +		return -EFAULT;
> >
> > -		if (info.argsz < minsz)
> > -			return -EINVAL;
> > +	if (info.argsz < minsz)
> > +		return -EINVAL;
> >
> > -		if (info.argsz >= capsz) {
> > -			minsz = capsz;
> > -			info.cap_offset = 0; /* output, no-recopy necessary */
> > -		}
> > +	if (info.argsz >= capsz) {
> > +		minsz = capsz;
> > +		info.cap_offset = 0; /* output, no-recopy necessary */
> > +	}
> >
> > -		mutex_lock(&iommu->lock);
> > -		info.flags = VFIO_IOMMU_INFO_PGSIZES;
> > +	mutex_lock(&iommu->lock);
> > +	info.flags = VFIO_IOMMU_INFO_PGSIZES;
> >
> > -		info.iova_pgsizes = iommu->pgsize_bitmap;
> > +	info.iova_pgsizes = iommu->pgsize_bitmap;
> >
> > -		ret = vfio_iommu_migration_build_caps(iommu, &caps);
> > +	ret = vfio_iommu_migration_build_caps(iommu, &caps);
> >
> > -		if (!ret)
> > -			ret = vfio_iommu_iova_build_caps(iommu, &caps);
> > +	if (!ret)
> > +		ret = vfio_iommu_iova_build_caps(iommu, &caps);
> >
> > -		mutex_unlock(&iommu->lock);
> > +	mutex_unlock(&iommu->lock);
> >
> > -		if (ret)
> > -			return ret;
> > +	if (ret)
> > +		return ret;
> >
> > -		if (caps.size) {
> > -			info.flags |= VFIO_IOMMU_INFO_CAPS;
> > +	if (caps.size) {
> > +		info.flags |= VFIO_IOMMU_INFO_CAPS;
> >
> > -			if (info.argsz < sizeof(info) + caps.size) {
> > -				info.argsz = sizeof(info) + caps.size;
> > -			} else {
> > -				vfio_info_cap_shift(&caps, sizeof(info));
> > -				if (copy_to_user((void __user *)arg +
> > -						sizeof(info), caps.buf,
> > -						caps.size)) {
> > -					kfree(caps.buf);
> > -					return -EFAULT;
> > -				}
> > -				info.cap_offset = sizeof(info);
> > +		if (info.argsz < sizeof(info) + caps.size) {
> > +			info.argsz = sizeof(info) + caps.size;
> > +		} else {
> > +			vfio_info_cap_shift(&caps, sizeof(info));
> > +			if (copy_to_user((void __user *)arg +
> > +					sizeof(info), caps.buf,
> > +					caps.size)) {
> > +				kfree(caps.buf);
> > +				return -EFAULT;
> >  			}
> > -
> > -			kfree(caps.buf);
> > +			info.cap_offset = sizeof(info);
> >  		}
> >
> > -		return copy_to_user((void __user *)arg, &info, minsz) ?
> > -			-EFAULT : 0;
> > +		kfree(caps.buf);
> > +	}
> >
> > -	} else if (cmd == VFIO_IOMMU_MAP_DMA) {
> > -		struct vfio_iommu_type1_dma_map map;
> > -		uint32_t mask = VFIO_DMA_MAP_FLAG_READ |
> > -				VFIO_DMA_MAP_FLAG_WRITE;
> > +	return copy_to_user((void __user *)arg, &info, minsz) ?
> > +			-EFAULT : 0;
> > +}
> >
> > -		minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
> > +static int vfio_iommu_type1_map_dma(struct vfio_iommu *iommu,
> > +				    unsigned long arg)
> > +{
> > +	struct vfio_iommu_type1_dma_map map;
> > +	unsigned long minsz;
> > +	uint32_t mask = VFIO_DMA_MAP_FLAG_READ |
> > +			VFIO_DMA_MAP_FLAG_WRITE;
> >
> > -		if (copy_from_user(&map, (void __user *)arg, minsz))
> > -			return -EFAULT;
> > +	minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
> >
> > -		if (map.argsz < minsz || map.flags & ~mask)
> > -			return -EINVAL;
> > +	if (copy_from_user(&map, (void __user *)arg, minsz))
> > +		return -EFAULT;
> >
> > -		return vfio_dma_do_map(iommu, &map);
> > +	if (map.argsz < minsz || map.flags & ~mask)
> > +		return -EINVAL;
> >
> > -	} else if (cmd == VFIO_IOMMU_UNMAP_DMA) {
> > -		struct vfio_iommu_type1_dma_unmap unmap;
> > -		struct vfio_bitmap bitmap = { 0 };
> > -		int ret;
> > +	return vfio_dma_do_map(iommu, &map); }
> >
> > -		minsz = offsetofend(struct vfio_iommu_type1_dma_unmap,
> size);
> > +static int vfio_iommu_type1_unmap_dma(struct vfio_iommu *iommu,
> > +				      unsigned long arg)
> > +{
> > +	struct vfio_iommu_type1_dma_unmap unmap;
> > +	struct vfio_bitmap bitmap = { 0 };
> > +	unsigned long minsz;
> > +	long ret;
> >
> > -		if (copy_from_user(&unmap, (void __user *)arg, minsz))
> > -			return -EFAULT;
> > +	minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size);
> >
> > -		if (unmap.argsz < minsz ||
> > -		    unmap.flags &
> ~VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP)
> > -			return -EINVAL;
> > +	if (copy_from_user(&unmap, (void __user *)arg, minsz))
> > +		return -EFAULT;
> >
> > -		if (unmap.flags &
> VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
> > -			unsigned long pgshift;
> > +	if (unmap.argsz < minsz ||
> > +	    unmap.flags & ~VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP)
> > +		return -EINVAL;
> >
> > -			if (unmap.argsz < (minsz + sizeof(bitmap)))
> > -				return -EINVAL;
> > +	if (unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
> > +		unsigned long pgshift;
> >
> > -			if (copy_from_user(&bitmap,
> > -					   (void __user *)(arg + minsz),
> > -					   sizeof(bitmap)))
> > -				return -EFAULT;
> > +		if (unmap.argsz < (minsz + sizeof(bitmap)))
> > +			return -EINVAL;
> >
> > -			if (!access_ok((void __user *)bitmap.data, bitmap.size))
> > -				return -EINVAL;
> > +		if (copy_from_user(&bitmap,
> > +				   (void __user *)(arg + minsz),
> > +				   sizeof(bitmap)))
> > +			return -EFAULT;
> >
> > -			pgshift = __ffs(bitmap.pgsize);
> > -			ret = verify_bitmap_size(unmap.size >> pgshift,
> > -						 bitmap.size);
> > -			if (ret)
> > -				return ret;
> > -		}
> > +		if (!access_ok((void __user *)bitmap.data, bitmap.size))
> > +			return -EINVAL;
> >
> > -		ret = vfio_dma_do_unmap(iommu, &unmap, &bitmap);
> > +		pgshift = __ffs(bitmap.pgsize);
> > +		ret = verify_bitmap_size(unmap.size >> pgshift,
> > +					 bitmap.size);
> >  		if (ret)
> >  			return ret;
> > +	}
> > +
> > +	ret = vfio_dma_do_unmap(iommu, &unmap, &bitmap);
> > +	if (ret)
> > +		return ret;
> >
> > -		return copy_to_user((void __user *)arg, &unmap, minsz) ?
> > +	return copy_to_user((void __user *)arg, &unmap, minsz) ?
> >  			-EFAULT : 0;
> > -	} else if (cmd == VFIO_IOMMU_DIRTY_PAGES) {
> > -		struct vfio_iommu_type1_dirty_bitmap dirty;
> > -		uint32_t mask = VFIO_IOMMU_DIRTY_PAGES_FLAG_START |
> > -				VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP |
> > -
> 	VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
> > -		int ret = 0;
> > +}
> >
> > -		if (!iommu->v2)
> > -			return -EACCES;
> > +static int vfio_iommu_type1_dirty_pages(struct vfio_iommu *iommu,
> > +					unsigned long arg)
> > +{
> > +	struct vfio_iommu_type1_dirty_bitmap dirty;
> > +	uint32_t mask = VFIO_IOMMU_DIRTY_PAGES_FLAG_START |
> > +			VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP |
> > +			VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
> > +	unsigned long minsz;
> > +	int ret = 0;
> >
> > -		minsz = offsetofend(struct vfio_iommu_type1_dirty_bitmap,
> > -				    flags);
> > +	if (!iommu->v2)
> > +		return -EACCES;
> >
> > -		if (copy_from_user(&dirty, (void __user *)arg, minsz))
> > -			return -EFAULT;
> > +	minsz = offsetofend(struct vfio_iommu_type1_dirty_bitmap,
> > +			    flags);
> >
> > -		if (dirty.argsz < minsz || dirty.flags & ~mask)
> > -			return -EINVAL;
> > +	if (copy_from_user(&dirty, (void __user *)arg, minsz))
> > +		return -EFAULT;
> > +
> > +	if (dirty.argsz < minsz || dirty.flags & ~mask)
> > +		return -EINVAL;
> > +
> > +	/* only one flag should be set at a time */
> > +	if (__ffs(dirty.flags) != __fls(dirty.flags))
> > +		return -EINVAL;
> > +
> > +	if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_START) {
> > +		size_t pgsize;
> >
> > -		/* only one flag should be set at a time */
> > -		if (__ffs(dirty.flags) != __fls(dirty.flags))
> > +		mutex_lock(&iommu->lock);
> > +		pgsize = 1 << __ffs(iommu->pgsize_bitmap);
> > +		if (!iommu->dirty_page_tracking) {
> > +			ret = vfio_dma_bitmap_alloc_all(iommu, pgsize);
> > +			if (!ret)
> > +				iommu->dirty_page_tracking = true;
> > +		}
> > +		mutex_unlock(&iommu->lock);
> > +		return ret;
> > +	} else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP) {
> > +		mutex_lock(&iommu->lock);
> > +		if (iommu->dirty_page_tracking) {
> > +			iommu->dirty_page_tracking = false;
> > +			vfio_dma_bitmap_free_all(iommu);
> > +		}
> > +		mutex_unlock(&iommu->lock);
> > +		return 0;
> > +	} else if (dirty.flags &
> > +			 VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP) {
> > +		struct vfio_iommu_type1_dirty_bitmap_get range;
> > +		unsigned long pgshift;
> > +		size_t data_size = dirty.argsz - minsz;
> > +		size_t iommu_pgsize;
> > +
> > +		if (!data_size || data_size < sizeof(range))
> >  			return -EINVAL;
> >
> > -		if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_START) {
> > -			size_t pgsize;
> > +		if (copy_from_user(&range, (void __user *)(arg + minsz),
> > +				   sizeof(range)))
> > +			return -EFAULT;
> >
> > -			mutex_lock(&iommu->lock);
> > -			pgsize = 1 << __ffs(iommu->pgsize_bitmap);
> > -			if (!iommu->dirty_page_tracking) {
> > -				ret = vfio_dma_bitmap_alloc_all(iommu, pgsize);
> > -				if (!ret)
> > -					iommu->dirty_page_tracking = true;
> > -			}
> > -			mutex_unlock(&iommu->lock);
> > +		if (range.iova + range.size < range.iova)
> > +			return -EINVAL;
> > +		if (!access_ok((void __user *)range.bitmap.data,
> > +			       range.bitmap.size))
> > +			return -EINVAL;
> > +
> > +		pgshift = __ffs(range.bitmap.pgsize);
> > +		ret = verify_bitmap_size(range.size >> pgshift,
> > +					 range.bitmap.size);
> > +		if (ret)
> >  			return ret;
> > -		} else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP)
> {
> > -			mutex_lock(&iommu->lock);
> > -			if (iommu->dirty_page_tracking) {
> > -				iommu->dirty_page_tracking = false;
> > -				vfio_dma_bitmap_free_all(iommu);
> > -			}
> > -			mutex_unlock(&iommu->lock);
> > -			return 0;
> > -		} else if (dirty.flags &
> > -
> VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP) {
> > -			struct vfio_iommu_type1_dirty_bitmap_get range;
> > -			unsigned long pgshift;
> > -			size_t data_size = dirty.argsz - minsz;
> > -			size_t iommu_pgsize;
> > -
> > -			if (!data_size || data_size < sizeof(range))
> > -				return -EINVAL;
> > -
> > -			if (copy_from_user(&range, (void __user *)(arg + minsz),
> > -					   sizeof(range)))
> > -				return -EFAULT;
> >
> > -			if (range.iova + range.size < range.iova)
> > -				return -EINVAL;
> > -			if (!access_ok((void __user *)range.bitmap.data,
> > -				       range.bitmap.size))
> > -				return -EINVAL;
> > +		mutex_lock(&iommu->lock);
> >
> > -			pgshift = __ffs(range.bitmap.pgsize);
> > -			ret = verify_bitmap_size(range.size >> pgshift,
> > -						 range.bitmap.size);
> > -			if (ret)
> > -				return ret;
> > +		iommu_pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
> >
> > -			mutex_lock(&iommu->lock);
> > +		/* allow only smallest supported pgsize */
> > +		if (range.bitmap.pgsize != iommu_pgsize) {
> > +			ret = -EINVAL;
> > +			goto out_unlock;
> > +		}
> > +		if (range.iova & (iommu_pgsize - 1)) {
> > +			ret = -EINVAL;
> > +			goto out_unlock;
> > +		}
> > +		if (!range.size || range.size & (iommu_pgsize - 1)) {
> > +			ret = -EINVAL;
> > +			goto out_unlock;
> > +		}
> >
> > -			iommu_pgsize = (size_t)1 << __ffs(iommu-
> >pgsize_bitmap);
> > +		if (iommu->dirty_page_tracking)
> > +			ret = vfio_iova_dirty_bitmap(range.bitmap.data,
> > +					iommu, range.iova, range.size,
> > +					range.bitmap.pgsize);
> > +		else
> > +			ret = -EINVAL;
> > +out_unlock:
> > +		mutex_unlock(&iommu->lock);
> >
> > -			/* allow only smallest supported pgsize */
> > -			if (range.bitmap.pgsize != iommu_pgsize) {
> > -				ret = -EINVAL;
> > -				goto out_unlock;
> > -			}
> > -			if (range.iova & (iommu_pgsize - 1)) {
> > -				ret = -EINVAL;
> > -				goto out_unlock;
> > -			}
> > -			if (!range.size || range.size & (iommu_pgsize - 1)) {
> > -				ret = -EINVAL;
> > -				goto out_unlock;
> > -			}
> > +		return ret;
> > +	}
> >
> > -			if (iommu->dirty_page_tracking)
> > -				ret = vfio_iova_dirty_bitmap(range.bitmap.data,
> > -						iommu, range.iova, range.size,
> > -						range.bitmap.pgsize);
> > -			else
> > -				ret = -EINVAL;
> > -out_unlock:
> > -			mutex_unlock(&iommu->lock);
> > +	return -EINVAL;
> > +}
> >
> > -			return ret;
> > -		}
> > +static long vfio_iommu_type1_ioctl(void *iommu_data,
> > +				   unsigned int cmd, unsigned long arg) {
> > +	struct vfio_iommu *iommu = iommu_data;
> > +
> > +	switch (cmd) {
> > +	case VFIO_CHECK_EXTENSION:
> > +		return vfio_iommu_type1_check_extension(iommu, arg);
> > +	case VFIO_IOMMU_GET_INFO:
> > +		return vfio_iommu_type1_get_info(iommu, arg);
> > +	case VFIO_IOMMU_MAP_DMA:
> > +		return vfio_iommu_type1_map_dma(iommu, arg);
> > +	case VFIO_IOMMU_UNMAP_DMA:
> > +		return vfio_iommu_type1_unmap_dma(iommu, arg);
> > +	case VFIO_IOMMU_DIRTY_PAGES:
> > +		return vfio_iommu_type1_dirty_pages(iommu, arg);
> >  	}
> >
> >  	return -ENOTTY;
diff mbox series

Patch

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 5e556ac..7accb59 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -2453,6 +2453,23 @@  static int vfio_domains_have_iommu_cache(struct vfio_iommu *iommu)
 	return ret;
 }
 
+static int vfio_iommu_type1_check_extension(struct vfio_iommu *iommu,
+					    unsigned long arg)
+{
+	switch (arg) {
+	case VFIO_TYPE1_IOMMU:
+	case VFIO_TYPE1v2_IOMMU:
+	case VFIO_TYPE1_NESTING_IOMMU:
+		return 1;
+	case VFIO_DMA_CC_IOMMU:
+		if (!iommu)
+			return 0;
+		return vfio_domains_have_iommu_cache(iommu);
+	default:
+		return 0;
+	}
+}
+
 static int vfio_iommu_iova_add_cap(struct vfio_info_cap *caps,
 		 struct vfio_iommu_type1_info_cap_iova_range *cap_iovas,
 		 size_t size)
@@ -2529,238 +2546,255 @@  static int vfio_iommu_migration_build_caps(struct vfio_iommu *iommu,
 	return vfio_info_add_capability(caps, &cap_mig.header, sizeof(cap_mig));
 }
 
-static long vfio_iommu_type1_ioctl(void *iommu_data,
-				   unsigned int cmd, unsigned long arg)
+static int vfio_iommu_type1_get_info(struct vfio_iommu *iommu,
+				     unsigned long arg)
 {
-	struct vfio_iommu *iommu = iommu_data;
+	struct vfio_iommu_type1_info info;
 	unsigned long minsz;
+	struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
+	unsigned long capsz;
+	int ret;
 
-	if (cmd == VFIO_CHECK_EXTENSION) {
-		switch (arg) {
-		case VFIO_TYPE1_IOMMU:
-		case VFIO_TYPE1v2_IOMMU:
-		case VFIO_TYPE1_NESTING_IOMMU:
-			return 1;
-		case VFIO_DMA_CC_IOMMU:
-			if (!iommu)
-				return 0;
-			return vfio_domains_have_iommu_cache(iommu);
-		default:
-			return 0;
-		}
-	} else if (cmd == VFIO_IOMMU_GET_INFO) {
-		struct vfio_iommu_type1_info info;
-		struct vfio_info_cap caps = { .buf = NULL, .size = 0 };
-		unsigned long capsz;
-		int ret;
-
-		minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes);
+	minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes);
 
-		/* For backward compatibility, cannot require this */
-		capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset);
+	/* For backward compatibility, cannot require this */
+	capsz = offsetofend(struct vfio_iommu_type1_info, cap_offset);
 
-		if (copy_from_user(&info, (void __user *)arg, minsz))
-			return -EFAULT;
+	if (copy_from_user(&info, (void __user *)arg, minsz))
+		return -EFAULT;
 
-		if (info.argsz < minsz)
-			return -EINVAL;
+	if (info.argsz < minsz)
+		return -EINVAL;
 
-		if (info.argsz >= capsz) {
-			minsz = capsz;
-			info.cap_offset = 0; /* output, no-recopy necessary */
-		}
+	if (info.argsz >= capsz) {
+		minsz = capsz;
+		info.cap_offset = 0; /* output, no-recopy necessary */
+	}
 
-		mutex_lock(&iommu->lock);
-		info.flags = VFIO_IOMMU_INFO_PGSIZES;
+	mutex_lock(&iommu->lock);
+	info.flags = VFIO_IOMMU_INFO_PGSIZES;
 
-		info.iova_pgsizes = iommu->pgsize_bitmap;
+	info.iova_pgsizes = iommu->pgsize_bitmap;
 
-		ret = vfio_iommu_migration_build_caps(iommu, &caps);
+	ret = vfio_iommu_migration_build_caps(iommu, &caps);
 
-		if (!ret)
-			ret = vfio_iommu_iova_build_caps(iommu, &caps);
+	if (!ret)
+		ret = vfio_iommu_iova_build_caps(iommu, &caps);
 
-		mutex_unlock(&iommu->lock);
+	mutex_unlock(&iommu->lock);
 
-		if (ret)
-			return ret;
+	if (ret)
+		return ret;
 
-		if (caps.size) {
-			info.flags |= VFIO_IOMMU_INFO_CAPS;
+	if (caps.size) {
+		info.flags |= VFIO_IOMMU_INFO_CAPS;
 
-			if (info.argsz < sizeof(info) + caps.size) {
-				info.argsz = sizeof(info) + caps.size;
-			} else {
-				vfio_info_cap_shift(&caps, sizeof(info));
-				if (copy_to_user((void __user *)arg +
-						sizeof(info), caps.buf,
-						caps.size)) {
-					kfree(caps.buf);
-					return -EFAULT;
-				}
-				info.cap_offset = sizeof(info);
+		if (info.argsz < sizeof(info) + caps.size) {
+			info.argsz = sizeof(info) + caps.size;
+		} else {
+			vfio_info_cap_shift(&caps, sizeof(info));
+			if (copy_to_user((void __user *)arg +
+					sizeof(info), caps.buf,
+					caps.size)) {
+				kfree(caps.buf);
+				return -EFAULT;
 			}
-
-			kfree(caps.buf);
+			info.cap_offset = sizeof(info);
 		}
 
-		return copy_to_user((void __user *)arg, &info, minsz) ?
-			-EFAULT : 0;
+		kfree(caps.buf);
+	}
 
-	} else if (cmd == VFIO_IOMMU_MAP_DMA) {
-		struct vfio_iommu_type1_dma_map map;
-		uint32_t mask = VFIO_DMA_MAP_FLAG_READ |
-				VFIO_DMA_MAP_FLAG_WRITE;
+	return copy_to_user((void __user *)arg, &info, minsz) ?
+			-EFAULT : 0;
+}
 
-		minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
+static int vfio_iommu_type1_map_dma(struct vfio_iommu *iommu,
+				    unsigned long arg)
+{
+	struct vfio_iommu_type1_dma_map map;
+	unsigned long minsz;
+	uint32_t mask = VFIO_DMA_MAP_FLAG_READ |
+			VFIO_DMA_MAP_FLAG_WRITE;
 
-		if (copy_from_user(&map, (void __user *)arg, minsz))
-			return -EFAULT;
+	minsz = offsetofend(struct vfio_iommu_type1_dma_map, size);
 
-		if (map.argsz < minsz || map.flags & ~mask)
-			return -EINVAL;
+	if (copy_from_user(&map, (void __user *)arg, minsz))
+		return -EFAULT;
 
-		return vfio_dma_do_map(iommu, &map);
+	if (map.argsz < minsz || map.flags & ~mask)
+		return -EINVAL;
 
-	} else if (cmd == VFIO_IOMMU_UNMAP_DMA) {
-		struct vfio_iommu_type1_dma_unmap unmap;
-		struct vfio_bitmap bitmap = { 0 };
-		int ret;
+	return vfio_dma_do_map(iommu, &map);
+}
 
-		minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size);
+static int vfio_iommu_type1_unmap_dma(struct vfio_iommu *iommu,
+				      unsigned long arg)
+{
+	struct vfio_iommu_type1_dma_unmap unmap;
+	struct vfio_bitmap bitmap = { 0 };
+	unsigned long minsz;
+	long ret;
 
-		if (copy_from_user(&unmap, (void __user *)arg, minsz))
-			return -EFAULT;
+	minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size);
 
-		if (unmap.argsz < minsz ||
-		    unmap.flags & ~VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP)
-			return -EINVAL;
+	if (copy_from_user(&unmap, (void __user *)arg, minsz))
+		return -EFAULT;
 
-		if (unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
-			unsigned long pgshift;
+	if (unmap.argsz < minsz ||
+	    unmap.flags & ~VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP)
+		return -EINVAL;
 
-			if (unmap.argsz < (minsz + sizeof(bitmap)))
-				return -EINVAL;
+	if (unmap.flags & VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP) {
+		unsigned long pgshift;
 
-			if (copy_from_user(&bitmap,
-					   (void __user *)(arg + minsz),
-					   sizeof(bitmap)))
-				return -EFAULT;
+		if (unmap.argsz < (minsz + sizeof(bitmap)))
+			return -EINVAL;
 
-			if (!access_ok((void __user *)bitmap.data, bitmap.size))
-				return -EINVAL;
+		if (copy_from_user(&bitmap,
+				   (void __user *)(arg + minsz),
+				   sizeof(bitmap)))
+			return -EFAULT;
 
-			pgshift = __ffs(bitmap.pgsize);
-			ret = verify_bitmap_size(unmap.size >> pgshift,
-						 bitmap.size);
-			if (ret)
-				return ret;
-		}
+		if (!access_ok((void __user *)bitmap.data, bitmap.size))
+			return -EINVAL;
 
-		ret = vfio_dma_do_unmap(iommu, &unmap, &bitmap);
+		pgshift = __ffs(bitmap.pgsize);
+		ret = verify_bitmap_size(unmap.size >> pgshift,
+					 bitmap.size);
 		if (ret)
 			return ret;
+	}
+
+	ret = vfio_dma_do_unmap(iommu, &unmap, &bitmap);
+	if (ret)
+		return ret;
 
-		return copy_to_user((void __user *)arg, &unmap, minsz) ?
+	return copy_to_user((void __user *)arg, &unmap, minsz) ?
 			-EFAULT : 0;
-	} else if (cmd == VFIO_IOMMU_DIRTY_PAGES) {
-		struct vfio_iommu_type1_dirty_bitmap dirty;
-		uint32_t mask = VFIO_IOMMU_DIRTY_PAGES_FLAG_START |
-				VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP |
-				VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
-		int ret = 0;
+}
 
-		if (!iommu->v2)
-			return -EACCES;
+static int vfio_iommu_type1_dirty_pages(struct vfio_iommu *iommu,
+					unsigned long arg)
+{
+	struct vfio_iommu_type1_dirty_bitmap dirty;
+	uint32_t mask = VFIO_IOMMU_DIRTY_PAGES_FLAG_START |
+			VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP |
+			VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP;
+	unsigned long minsz;
+	int ret = 0;
 
-		minsz = offsetofend(struct vfio_iommu_type1_dirty_bitmap,
-				    flags);
+	if (!iommu->v2)
+		return -EACCES;
 
-		if (copy_from_user(&dirty, (void __user *)arg, minsz))
-			return -EFAULT;
+	minsz = offsetofend(struct vfio_iommu_type1_dirty_bitmap,
+			    flags);
 
-		if (dirty.argsz < minsz || dirty.flags & ~mask)
-			return -EINVAL;
+	if (copy_from_user(&dirty, (void __user *)arg, minsz))
+		return -EFAULT;
+
+	if (dirty.argsz < minsz || dirty.flags & ~mask)
+		return -EINVAL;
+
+	/* only one flag should be set at a time */
+	if (__ffs(dirty.flags) != __fls(dirty.flags))
+		return -EINVAL;
+
+	if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_START) {
+		size_t pgsize;
 
-		/* only one flag should be set at a time */
-		if (__ffs(dirty.flags) != __fls(dirty.flags))
+		mutex_lock(&iommu->lock);
+		pgsize = 1 << __ffs(iommu->pgsize_bitmap);
+		if (!iommu->dirty_page_tracking) {
+			ret = vfio_dma_bitmap_alloc_all(iommu, pgsize);
+			if (!ret)
+				iommu->dirty_page_tracking = true;
+		}
+		mutex_unlock(&iommu->lock);
+		return ret;
+	} else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP) {
+		mutex_lock(&iommu->lock);
+		if (iommu->dirty_page_tracking) {
+			iommu->dirty_page_tracking = false;
+			vfio_dma_bitmap_free_all(iommu);
+		}
+		mutex_unlock(&iommu->lock);
+		return 0;
+	} else if (dirty.flags &
+			 VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP) {
+		struct vfio_iommu_type1_dirty_bitmap_get range;
+		unsigned long pgshift;
+		size_t data_size = dirty.argsz - minsz;
+		size_t iommu_pgsize;
+
+		if (!data_size || data_size < sizeof(range))
 			return -EINVAL;
 
-		if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_START) {
-			size_t pgsize;
+		if (copy_from_user(&range, (void __user *)(arg + minsz),
+				   sizeof(range)))
+			return -EFAULT;
 
-			mutex_lock(&iommu->lock);
-			pgsize = 1 << __ffs(iommu->pgsize_bitmap);
-			if (!iommu->dirty_page_tracking) {
-				ret = vfio_dma_bitmap_alloc_all(iommu, pgsize);
-				if (!ret)
-					iommu->dirty_page_tracking = true;
-			}
-			mutex_unlock(&iommu->lock);
+		if (range.iova + range.size < range.iova)
+			return -EINVAL;
+		if (!access_ok((void __user *)range.bitmap.data,
+			       range.bitmap.size))
+			return -EINVAL;
+
+		pgshift = __ffs(range.bitmap.pgsize);
+		ret = verify_bitmap_size(range.size >> pgshift,
+					 range.bitmap.size);
+		if (ret)
 			return ret;
-		} else if (dirty.flags & VFIO_IOMMU_DIRTY_PAGES_FLAG_STOP) {
-			mutex_lock(&iommu->lock);
-			if (iommu->dirty_page_tracking) {
-				iommu->dirty_page_tracking = false;
-				vfio_dma_bitmap_free_all(iommu);
-			}
-			mutex_unlock(&iommu->lock);
-			return 0;
-		} else if (dirty.flags &
-				 VFIO_IOMMU_DIRTY_PAGES_FLAG_GET_BITMAP) {
-			struct vfio_iommu_type1_dirty_bitmap_get range;
-			unsigned long pgshift;
-			size_t data_size = dirty.argsz - minsz;
-			size_t iommu_pgsize;
-
-			if (!data_size || data_size < sizeof(range))
-				return -EINVAL;
-
-			if (copy_from_user(&range, (void __user *)(arg + minsz),
-					   sizeof(range)))
-				return -EFAULT;
 
-			if (range.iova + range.size < range.iova)
-				return -EINVAL;
-			if (!access_ok((void __user *)range.bitmap.data,
-				       range.bitmap.size))
-				return -EINVAL;
+		mutex_lock(&iommu->lock);
 
-			pgshift = __ffs(range.bitmap.pgsize);
-			ret = verify_bitmap_size(range.size >> pgshift,
-						 range.bitmap.size);
-			if (ret)
-				return ret;
+		iommu_pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
 
-			mutex_lock(&iommu->lock);
+		/* allow only smallest supported pgsize */
+		if (range.bitmap.pgsize != iommu_pgsize) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+		if (range.iova & (iommu_pgsize - 1)) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+		if (!range.size || range.size & (iommu_pgsize - 1)) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
 
-			iommu_pgsize = (size_t)1 << __ffs(iommu->pgsize_bitmap);
+		if (iommu->dirty_page_tracking)
+			ret = vfio_iova_dirty_bitmap(range.bitmap.data,
+					iommu, range.iova, range.size,
+					range.bitmap.pgsize);
+		else
+			ret = -EINVAL;
+out_unlock:
+		mutex_unlock(&iommu->lock);
 
-			/* allow only smallest supported pgsize */
-			if (range.bitmap.pgsize != iommu_pgsize) {
-				ret = -EINVAL;
-				goto out_unlock;
-			}
-			if (range.iova & (iommu_pgsize - 1)) {
-				ret = -EINVAL;
-				goto out_unlock;
-			}
-			if (!range.size || range.size & (iommu_pgsize - 1)) {
-				ret = -EINVAL;
-				goto out_unlock;
-			}
+		return ret;
+	}
 
-			if (iommu->dirty_page_tracking)
-				ret = vfio_iova_dirty_bitmap(range.bitmap.data,
-						iommu, range.iova, range.size,
-						range.bitmap.pgsize);
-			else
-				ret = -EINVAL;
-out_unlock:
-			mutex_unlock(&iommu->lock);
+	return -EINVAL;
+}
 
-			return ret;
-		}
+static long vfio_iommu_type1_ioctl(void *iommu_data,
+				   unsigned int cmd, unsigned long arg)
+{
+	struct vfio_iommu *iommu = iommu_data;
+
+	switch (cmd) {
+	case VFIO_CHECK_EXTENSION:
+		return vfio_iommu_type1_check_extension(iommu, arg);
+	case VFIO_IOMMU_GET_INFO:
+		return vfio_iommu_type1_get_info(iommu, arg);
+	case VFIO_IOMMU_MAP_DMA:
+		return vfio_iommu_type1_map_dma(iommu, arg);
+	case VFIO_IOMMU_UNMAP_DMA:
+		return vfio_iommu_type1_unmap_dma(iommu, arg);
+	case VFIO_IOMMU_DIRTY_PAGES:
+		return vfio_iommu_type1_dirty_pages(iommu, arg);
 	}
 
 	return -ENOTTY;