[PATCH v3] vfio/type1: Fix vfio_find_dma_valid return

[PATCH v3] vfio/type1: Fix vfio_find_dma_valid return

[Anthony Yznaga]

vfio_find_dma_valid is defined to return WAITED on success if it was
necessary to wait.  However, the loop forgets the WAITED value returned
by vfio_wait() and returns 0 in a later iteration.  Fix it.

Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
Reviewed-by: Steve Sistare <steven.sistare@oracle.com>

---
v3:
  use Steve Sistare's suggested commit text and add his R-b
v2:
  use Alex Williamson's simplified fix

 drivers/vfio/vfio_iommu_type1.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 0b4f7c174c7a..0e9217687f5c 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -612,17 +612,17 @@ static int vfio_wait(struct vfio_iommu *iommu)
 static int vfio_find_dma_valid(struct vfio_iommu *iommu, dma_addr_t start,
 			       size_t size, struct vfio_dma **dma_p)
 {
-	int ret;
+	int ret = 0;
 
 	do {
 		*dma_p = vfio_find_dma(iommu, start, size);
 		if (!*dma_p)
-			ret = -EINVAL;
+			return -EINVAL;
 		else if (!(*dma_p)->vaddr_invalid)
-			ret = 0;
+			return ret;
 		else
 			ret = vfio_wait(iommu);
-	} while (ret > 0);
+	} while (ret == WAITED);
 
 	return ret;
 }
-- 
1.8.3.1

Re: [PATCH v3] vfio/type1: Fix vfio_find_dma_valid return

[Alex Williamson]

On Mon, 23 Aug 2021 09:35:50 -0700
Anthony Yznaga <anthony.yznaga@oracle.com> wrote:

> vfio_find_dma_valid is defined to return WAITED on success if it was
> necessary to wait.  However, the loop forgets the WAITED value returned
> by vfio_wait() and returns 0 in a later iteration.  Fix it.
> 
> Signed-off-by: Anthony Yznaga <anthony.yznaga@oracle.com>
> Reviewed-by: Steve Sistare <steven.sistare@oracle.com>
> 
> ---
> v3:
>   use Steve Sistare's suggested commit text and add his R-b
> v2:
>   use Alex Williamson's simplified fix
> 
>  drivers/vfio/vfio_iommu_type1.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)

Applied to vfio next branch for v5.15.  Thanks,

Alex