[PATCH 0/4] Fix checking of iommu_map_sgtable return value

[PATCH 0/4] Fix checking of iommu_map_sgtable return value

[Mikko Perttunen]

The return value of iommu_map_sgtable changed from unsigned to signed
quite a while ago, but not all callers were updated. Do that.

Each patch is independent of each other. The drm/msm patch additionally
changes from WARNing in case of mapping error to returning the error
code now available.

Best regards
Mikko

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
---
Mikko Perttunen (4):
      gpu: host1x: Fix iommu_map_sgtable() return value check
      drm/tegra: Fix iommu_map_sgtable() return value check
      drm/msm: Fix iommu_map_sgtable() return value check and avoid WARN
      media: nvidia: tegra-vde: Fix iommu_map_sgtable() return value check

 drivers/gpu/drm/msm/msm_iommu.c                 |  5 +++--
 drivers/gpu/drm/tegra/gem.c                     |  9 ++++++---
 drivers/gpu/host1x/job.c                        | 10 ++++++----
 drivers/media/platform/nvidia/tegra-vde/iommu.c |  9 +++++----
 4 files changed, 20 insertions(+), 13 deletions(-)
---
base-commit: 028ef9c96e96197026887c0f092424679298aae8
change-id: 20260417-iommu_map_sgtable-return-a8d3cd591fbc

[PATCH 1/4] gpu: host1x: Fix iommu_map_sgtable() return value check

[Mikko Perttunen]

Commit "iommu: return full error code from iommu_map_sg[_atomic]()"
changed iommu_map_sgtable() to return an ssize_t and negative values
in error cases, rather than a size_t and a zero.

pin_job() also was incorrectly assigning to 'int', which could cause
overflows into negative values.

Update pin_job() to correctly check for errors from iommu_map_sgtable.

Fixes: ad8f36e4b6b1 ("iommu: return full error code from iommu_map_sg[_atomic]()")
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
---
 drivers/gpu/host1x/job.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/host1x/job.c b/drivers/gpu/host1x/job.c
index 3ed49e1fd933..70bda32f1ff4 100644
--- a/drivers/gpu/host1x/job.c
+++ b/drivers/gpu/host1x/job.c
@@ -235,6 +235,8 @@ static unsigned int pin_job(struct host1x *host, struct host1x_job *job)
 		}
 
 		if (host->domain) {
+			ssize_t map_err;
+
 			for_each_sgtable_sg(map->sgt, sg, j)
 				gather_size += sg->length;
 
@@ -248,11 +250,11 @@ static unsigned int pin_job(struct host1x *host, struct host1x_job *job)
 				goto put;
 			}
 
-			err = iommu_map_sgtable(host->domain, iova_dma_addr(&host->iova, alloc),
-						map->sgt, IOMMU_READ);
-			if (err == 0) {
+			map_err = iommu_map_sgtable(host->domain, iova_dma_addr(&host->iova, alloc),
+						    map->sgt, IOMMU_READ);
+			if (map_err < 0) {
 				__free_iova(&host->iova, alloc);
-				err = -EINVAL;
+				err = map_err;
 				goto put;
 			}
 

-- 
2.53.0

[PATCH 2/4] drm/tegra: Fix iommu_map_sgtable() return value check

[Mikko Perttunen]

Commit "iommu: return full error code from iommu_map_sg[_atomic]()"
changed iommu_map_sgtable() to return an ssize_t and negative values
in error cases, rather than a size_t and a zero.

Update tegra_bo_iommu_map() to correctly check for errors from
iommu_map_sgtable.

Fixes: ad8f36e4b6b1 ("iommu: return full error code from iommu_map_sg[_atomic]()")
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
---
 drivers/gpu/drm/tegra/gem.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c
index d2bae88ad545..684a16be2c0f 100644
--- a/drivers/gpu/drm/tegra/gem.c
+++ b/drivers/gpu/drm/tegra/gem.c
@@ -235,6 +235,7 @@ static const struct host1x_bo_ops tegra_bo_ops = {
 static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo)
 {
 	int prot = IOMMU_READ | IOMMU_WRITE;
+	ssize_t size;
 	int err;
 
 	if (bo->mm)
@@ -256,13 +257,15 @@ static int tegra_bo_iommu_map(struct tegra_drm *tegra, struct tegra_bo *bo)
 
 	bo->iova = bo->mm->start;
 
-	bo->size = iommu_map_sgtable(tegra->domain, bo->iova, bo->sgt, prot);
-	if (!bo->size) {
+	size = iommu_map_sgtable(tegra->domain, bo->iova, bo->sgt, prot);
+	if (size < 0) {
 		dev_err(tegra->drm->dev, "failed to map buffer\n");
-		err = -ENOMEM;
+		err = size;
 		goto remove;
 	}
 
+	bo->size = size;
+
 	mutex_unlock(&tegra->mm_lock);
 
 	return 0;

-- 
2.53.0

[PATCH 3/4] drm/msm: Fix iommu_map_sgtable() return value check and avoid WARN

[Mikko Perttunen]

Commit "iommu: return full error code from iommu_map_sg[_atomic]()"
changed iommu_map_sgtable() to return an ssize_t and negative values
in error cases, rather than a size_t and a zero.

Store the return value in the appropriate type and in case of error,
return it rather than WARNing.

Fixes: ad8f36e4b6b1 ("iommu: return full error code from iommu_map_sg[_atomic]()")
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
---
 drivers/gpu/drm/msm/msm_iommu.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c
index 7d449e5202c5..058c71c82cf5 100644
--- a/drivers/gpu/drm/msm/msm_iommu.c
+++ b/drivers/gpu/drm/msm/msm_iommu.c
@@ -677,7 +677,7 @@ static int msm_iommu_map(struct msm_mmu *mmu, uint64_t iova,
 			 int prot)
 {
 	struct msm_iommu *iommu = to_msm_iommu(mmu);
-	size_t ret;
+	ssize_t ret;
 
 	WARN_ON(off != 0);
 
@@ -686,7 +686,8 @@ static int msm_iommu_map(struct msm_mmu *mmu, uint64_t iova,
 		iova |= GENMASK_ULL(63, 49);
 
 	ret = iommu_map_sgtable(iommu->domain, iova, sgt, prot);
-	WARN_ON(!ret);
+	if (ret < 0)
+		return ret;
 
 	return (ret == len) ? 0 : -EINVAL;
 }

-- 
2.53.0

[PATCH 4/4] media: nvidia: tegra-vde: Fix iommu_map_sgtable() return value check

[Mikko Perttunen]

Commit "iommu: return full error code from iommu_map_sg[_atomic]()"
changed iommu_map_sgtable() to return an ssize_t and negative values
in error cases, rather than a size_t and a zero.

Update tegra_vde_iommu_map() to correctly check for errors from
iommu_map_sgtable.

Fixes: ad8f36e4b6b1 ("iommu: return full error code from iommu_map_sg[_atomic]()")
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
---
 drivers/media/platform/nvidia/tegra-vde/iommu.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/media/platform/nvidia/tegra-vde/iommu.c b/drivers/media/platform/nvidia/tegra-vde/iommu.c
index b1d9d841d944..824d2aa80a43 100644
--- a/drivers/media/platform/nvidia/tegra-vde/iommu.c
+++ b/drivers/media/platform/nvidia/tegra-vde/iommu.c
@@ -25,6 +25,7 @@ int tegra_vde_iommu_map(struct tegra_vde *vde,
 	unsigned long shift;
 	unsigned long end;
 	dma_addr_t addr;
+	ssize_t map_err;
 
 	end = vde->domain->geometry.aperture_end;
 	size = iova_align(&vde->iova, size);
@@ -36,11 +37,11 @@ int tegra_vde_iommu_map(struct tegra_vde *vde,
 
 	addr = iova_dma_addr(&vde->iova, iova);
 
-	size = iommu_map_sgtable(vde->domain, addr, sgt,
-				 IOMMU_READ | IOMMU_WRITE);
-	if (!size) {
+	map_err = iommu_map_sgtable(vde->domain, addr, sgt,
+				    IOMMU_READ | IOMMU_WRITE);
+	if (map_err < 0) {
 		__free_iova(&vde->iova, iova);
-		return -ENXIO;
+		return map_err;
 	}
 
 	*iovap = iova;

-- 
2.53.0