Merge tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd

Pull iommufd updates from Jason Gunthorpe:
 "This is a pretty consequential cycle for iommufd, though this pull is
  not too big. It is based on a shared branch with VFIO that introduces
  VFIO_DEVICE_FEATURE_DMA_BUF a DMABUF exporter for VFIO device's MMIO
  PCI BARs. This was a large multiple series journey over the last year
  and a half.

  Based on that work IOMMUFD gains support for VFIO DMABUF's in its
  existing IOMMU_IOAS_MAP_FILE, which closes the last major gap to
  support PCI peer to peer transfers within VMs.

  In Joerg's iommu tree we have the "generic page table" work which aims
  to consolidate all the duplicated page table code in every iommu
  driver into a single algorithm. This will be used by iommufd to
  implement unique page table operations to start adding new features
  and improve performance.

  In here:

   - Expand IOMMU_IOAS_MAP_FILE to accept a DMABUF exported from VFIO.
     This is the first step to broader DMABUF support in iommufd, right
     now it only works with VFIO. This closes the last functional gap
     with classic VFIO type 1 to safely support PCI peer to peer DMA by
     mapping the VFIO device's MMIO into the IOMMU.

   - Relax SMMUv3 restrictions on nesting domains to better support
     qemu's sequence to have an identity mapping before the vSID is
     established"

* tag 'for-linus-iommufd' of git://git.kernel.org/pub/scm/linux/kernel/git/jgg/iommufd:
  iommu/arm-smmu-v3-iommufd: Allow attaching nested domain for GBPA cases
  iommufd/selftest: Add some tests for the dmabuf flow
  iommufd: Accept a DMABUF through IOMMU_IOAS_MAP_FILE
  iommufd: Have iopt_map_file_pages convert the fd to a file
  iommufd: Have pfn_reader process DMABUF iopt_pages
  iommufd: Allow MMIO pages in a batch
  iommufd: Allow a DMABUF to be revoked
  iommufd: Do not map/unmap revoked DMABUFs
  iommufd: Add DMABUF to iopt_pages
  vfio/pci: Add vfio_pci_dma_buf_iommufd_map()

2 files changed, 87 insertions, 0 deletions

diff --git a/tools/testing/selftests/iommu/iommufd.c b/tools/testing/selftests/iommu/iommufd.c
index 55c6658cece1..10e051b6f592 100644
--- a/tools/testing/selftests/iommu/iommufd.c
+++ b/tools/testing/selftests/iommu/iommufd.c
@@ -1571,6 +1571,49 @@ TEST_F(iommufd_ioas, copy_sweep)
 	test_ioctl_destroy(dst_ioas_id);
 }
 
+TEST_F(iommufd_ioas, dmabuf_simple)
+{
+	size_t buf_size = PAGE_SIZE*4;
+	__u64 iova;
+	int dfd;
+
+	test_cmd_get_dmabuf(buf_size, &dfd);
+	test_err_ioctl_ioas_map_file(EINVAL, dfd, 0, 0, &iova);
+	test_err_ioctl_ioas_map_file(EINVAL, dfd, buf_size, buf_size, &iova);
+	test_err_ioctl_ioas_map_file(EINVAL, dfd, 0, buf_size + 1, &iova);
+	test_ioctl_ioas_map_file(dfd, 0, buf_size, &iova);
+
+	close(dfd);
+}
+
+TEST_F(iommufd_ioas, dmabuf_revoke)
+{
+	size_t buf_size = PAGE_SIZE*4;
+	__u32 hwpt_id;
+	__u64 iova;
+	__u64 iova2;
+	int dfd;
+
+	test_cmd_get_dmabuf(buf_size, &dfd);
+	test_ioctl_ioas_map_file(dfd, 0, buf_size, &iova);
+	test_cmd_revoke_dmabuf(dfd, true);
+
+	if (variant->mock_domains)
+		test_cmd_hwpt_alloc(self->device_id, self->ioas_id, 0,
+				    &hwpt_id);
+
+	test_err_ioctl_ioas_map_file(ENODEV, dfd, 0, buf_size, &iova2);
+
+	test_cmd_revoke_dmabuf(dfd, false);
+	test_ioctl_ioas_map_file(dfd, 0, buf_size, &iova2);
+
+	/* Restore the iova back */
+	test_ioctl_ioas_unmap(iova, buf_size);
+	test_ioctl_ioas_map_fixed_file(dfd, 0, buf_size, iova);
+
+	close(dfd);
+}
+
 FIXTURE(iommufd_mock_domain)
 {
 	int fd;
diff --git a/tools/testing/selftests/iommu/iommufd_utils.h b/tools/testing/selftests/iommu/iommufd_utils.h
index 4d9d19a1c6f6..0a0ff6f7926d 100644
--- a/tools/testing/selftests/iommu/iommufd_utils.h
+++ b/tools/testing/selftests/iommu/iommufd_utils.h
@@ -560,6 +560,39 @@ static int _test_cmd_destroy_access_pages(int fd, unsigned int access_id,
 	EXPECT_ERRNO(_errno, _test_cmd_destroy_access_pages(              \
 				     self->fd, access_id, access_pages_id))
 
+static int _test_cmd_get_dmabuf(int fd, size_t len, int *out_fd)
+{
+	struct iommu_test_cmd cmd = {
+		.size = sizeof(cmd),
+		.op = IOMMU_TEST_OP_DMABUF_GET,
+		.dmabuf_get = { .length = len, .open_flags = O_CLOEXEC },
+	};
+
+	*out_fd = ioctl(fd, IOMMU_TEST_CMD, &cmd);
+	if (*out_fd < 0)
+		return -1;
+	return 0;
+}
+#define test_cmd_get_dmabuf(len, out_fd) \
+	ASSERT_EQ(0, _test_cmd_get_dmabuf(self->fd, len, out_fd))
+
+static int _test_cmd_revoke_dmabuf(int fd, int dmabuf_fd, bool revoked)
+{
+	struct iommu_test_cmd cmd = {
+		.size = sizeof(cmd),
+		.op = IOMMU_TEST_OP_DMABUF_REVOKE,
+		.dmabuf_revoke = { .dmabuf_fd = dmabuf_fd, .revoked = revoked },
+	};
+	int ret;
+
+	ret = ioctl(fd, IOMMU_TEST_CMD, &cmd);
+	if (ret < 0)
+		return -1;
+	return 0;
+}
+#define test_cmd_revoke_dmabuf(dmabuf_fd, revoke) \
+	ASSERT_EQ(0, _test_cmd_revoke_dmabuf(self->fd, dmabuf_fd, revoke))
+
 static int _test_ioctl_destroy(int fd, unsigned int id)
 {
 	struct iommu_destroy cmd = {
@@ -730,6 +763,17 @@ static int _test_ioctl_ioas_map_file(int fd, unsigned int ioas_id, int mfd,
 			  self->fd, ioas_id, mfd, start, length, iova_p,     \
 			  IOMMU_IOAS_MAP_WRITEABLE | IOMMU_IOAS_MAP_READABLE))
 
+#define test_ioctl_ioas_map_fixed_file(mfd, start, length, iova)          \
+	({                                                                \
+		__u64 __iova = iova;                                      \
+		ASSERT_EQ(0, _test_ioctl_ioas_map_file(                   \
+				     self->fd, self->ioas_id, mfd, start, \
+				     length, &__iova,                     \
+				     IOMMU_IOAS_MAP_FIXED_IOVA |          \
+					     IOMMU_IOAS_MAP_WRITEABLE |   \
+					     IOMMU_IOAS_MAP_READABLE));   \
+	})
+
 static int _test_ioctl_set_temp_memory_limit(int fd, unsigned int limit)
 {
 	struct iommu_test_cmd memlimit_cmd = {