On 5/30/24 3:58 PM, Dmitry Baryshkov wrote:
On Thu, 30 May 2024 at 04:59, Baolu Lu<baolu.lu@xxxxxxxxxxxxxxx> wrote:
On 5/29/24 4:21 PM, Dmitry Baryshkov wrote:
On Wed, May 29, 2024 at 01:32:36PM +0800, Lu Baolu wrote:
The domain allocated in msm_iommu_new() is for the @dev. Replace
iommu_domain_alloc() with iommu_paging_domain_alloc() to make it explicit.
Update msm_iommu_new() to always return ERR_PTR in failure cases instead
of NULL.
Please don't mix unrelated changes, because ...
Signed-off-by: Lu Baolu<baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/gpu/drm/msm/msm_iommu.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c
index d5512037c38b..f7e28d4b5f62 100644
--- a/drivers/gpu/drm/msm/msm_iommu.c
+++ b/drivers/gpu/drm/msm/msm_iommu.c
@@ -407,9 +407,9 @@ struct msm_mmu *msm_iommu_new(struct device *dev, unsigned long quirks)
struct msm_iommu *iommu;
int ret;
- domain = iommu_domain_alloc(dev->bus);
- if (!domain)
- return NULL;
+ domain = iommu_paging_domain_alloc(dev);
+ if (IS_ERR(domain))
+ return ERR_CAST(domain);
iommu_set_pgtable_quirks(domain, quirks);
@@ -441,7 +441,7 @@ struct msm_mmu *msm_iommu_gpu_new(struct device *dev, struct msm_gpu *gpu, unsig
struct msm_mmu *mmu;
mmu = msm_iommu_new(dev, quirks);
- if (IS_ERR_OR_NULL(mmu))
+ if (IS_ERR(mmu))
return mmu;
NAK, not having an IOMMU is a poor but legit usecase for some of devices
which don't have IOMMU support yet (for example because of the buggy
implementation for which we were not able to get all the hooks in).
Please don't break compatibility for existing platforms.
Sure. I will remove this line of change. Though I have no idea in which
case msm_iommu_new() could return NULL after this patch.
So, even without this chunk you are going to break the no-IOMMU case.
Please don't. This will result in a regression report and a revert.
Instead please provide a way for the existing drivers to continue
working. For example, something like:
if (IS_ERR(mmu) && ERR_PTR(mmu) == -ENODEV))
return NULL;
Oh I see. msm_iommu_new() returning NULL indicates a no-IOMMU case,
right? So perhaps we can make it explicit like below?
if (!device_iommu_mapped(dev))
return NULL;
domain = iommu_paging_domain_alloc(dev);
if (IS_ERR(domain))
return ERR_CAST(domain);
Best regards,
baolu
