Commit 44ebaa17 authored by Jason Gunthorpe's avatar Jason Gunthorpe
Browse files

iommufd: Accept a DMABUF through IOMMU_IOAS_MAP_FILE 

Finally call iopt_alloc_dmabuf_pages() if the user passed in a DMABUF
through IOMMU_IOAS_MAP_FILE. This makes the feature visible to userspace.

Link: https://patch.msgid.link/r/8-v2-b2c110338e3f+5c2-iommufd_dmabuf_jgg@nvidia.com


Reviewed-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Tested-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Tested-by: default avatarShuai Xue <xueshuai@linux.alibaba.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 217725f0

drivers/iommu/iommufd/io_pagetable.c

+33 −10
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 
 * The datastructure uses the iopt_pages to optimize the storage of the PFNs

 * between the domains and xarray.

 */

#include <linux/dma-buf.h>

#include <linux/err.h>

#include <linux/errno.h>

#include <linux/file.h>
@@ -484,19 +485,41 @@ int iopt_map_file_pages(struct iommufd_ctx *ictx, struct io_pagetable *iopt, 
			unsigned int flags)

{

	struct iopt_pages *pages;

	struct dma_buf *dmabuf;

	unsigned long start_byte;

	unsigned long last;



	if (!length)

		return -EINVAL;

	if (check_add_overflow(start, length - 1, &last))

		return -EOVERFLOW;



	start_byte = start - ALIGN_DOWN(start, PAGE_SIZE);

	dmabuf = dma_buf_get(fd);

	if (!IS_ERR(dmabuf)) {

		pages = iopt_alloc_dmabuf_pages(ictx, dmabuf, start_byte, start,

						length,

						iommu_prot & IOMMU_WRITE);

		if (IS_ERR(pages)) {

			dma_buf_put(dmabuf);

			return PTR_ERR(pages);

		}

	} else {

		struct file *file;



		file = fget(fd);

		if (!file)

			return -EBADF;



	pages = iopt_alloc_file_pages(file, start, length,

		pages = iopt_alloc_file_pages(file, start_byte, start, length,

					      iommu_prot & IOMMU_WRITE);

		fput(file);

		if (IS_ERR(pages))

			return PTR_ERR(pages);

	}



	return iopt_map_common(ictx, iopt, pages, iova, length,

			       start - pages->start, iommu_prot, flags);

			       start_byte, iommu_prot, flags);

}



struct iova_bitmap_fn_arg {

drivers/iommu/iommufd/io_pagetable.h

+3 −1
Original line number Diff line number Diff line
@@ -265,7 +265,9 @@ static inline bool iopt_dmabuf_revoked(struct iopt_pages *pages) 


struct iopt_pages *iopt_alloc_user_pages(void __user *uptr,

					 unsigned long length, bool writable);

struct iopt_pages *iopt_alloc_file_pages(struct file *file, unsigned long start,

struct iopt_pages *iopt_alloc_file_pages(struct file *file,

					 unsigned long start_byte,

					 unsigned long start,

					 unsigned long length, bool writable);

struct iopt_pages *iopt_alloc_dmabuf_pages(struct iommufd_ctx *ictx,

					   struct dma_buf *dmabuf,

drivers/iommu/iommufd/pages.c

+5 −8
Original line number Diff line number Diff line
@@ -1413,22 +1413,19 @@ struct iopt_pages *iopt_alloc_user_pages(void __user *uptr, 
	return pages;

}



struct iopt_pages *iopt_alloc_file_pages(struct file *file, unsigned long start,

struct iopt_pages *iopt_alloc_file_pages(struct file *file,

					 unsigned long start_byte,

					 unsigned long start,

					 unsigned long length, bool writable)



{

	struct iopt_pages *pages;

	unsigned long start_down = ALIGN_DOWN(start, PAGE_SIZE);

	unsigned long end;



	if (length && check_add_overflow(start, length - 1, &end))

		return ERR_PTR(-EOVERFLOW);



	pages = iopt_alloc_pages(start - start_down, length, writable);

	pages = iopt_alloc_pages(start_byte, length, writable);

	if (IS_ERR(pages))

		return pages;

	pages->file = get_file(file);

	pages->start = start_down;

	pages->start = start - start_byte;

	pages->type = IOPT_ADDRESS_FILE;

	return pages;

}