[PATCH v2 5/5] iommu/arm-smmu: Convert to domain_alloc_paging()

[Will Deacon]

On Tue, Dec 12, 2023 at 02:10:23PM +0000, Will Deacon wrote:
> On Tue, Dec 12, 2023 at 10:03:07AM -0400, Jason Gunthorpe wrote:
> > On Tue, Dec 12, 2023 at 01:26:51PM +0000, Will Deacon wrote:
> > > Why do we need to handle the 'dev && !cfg' case here, instead g
> > > returning NULL?
> > 
> > dev && !cfg is impossible these days, so we can shuffle the if and
> > then just crash on that case like the other drivers do.
> 
> Thanks, that would simplify it a little.

Folded in the diff below.

Will

--->8

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
index 536e47e3a65a..b0a6b367d8a2 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
@@ -861,7 +861,6 @@ static void arm_smmu_destroy_domain_context(struct arm_smmu_domain *smmu_domain)
 
 static struct iommu_domain *arm_smmu_domain_alloc_paging(struct device *dev)
 {
-	struct arm_smmu_master_cfg *cfg = NULL;
 	struct arm_smmu_domain *smmu_domain;
 
 	/*
@@ -876,13 +875,10 @@ static struct iommu_domain *arm_smmu_domain_alloc_paging(struct device *dev)
 	mutex_init(&smmu_domain->init_mutex);
 	spin_lock_init(&smmu_domain->cb_lock);
 
-	if (dev)
-		cfg = dev_iommu_priv_get(dev);
-	if (cfg) {
-		int ret;
+	if (dev) {
+		struct arm_smmu_master_cfg *cfg = dev_iommu_priv_get(dev);
 
-		ret = arm_smmu_init_domain_context(smmu_domain, cfg->smmu, dev);
-		if (ret) {
+		if (arm_smmu_init_domain_context(smmu_domain, cfg->smmu, dev)) {
 			kfree(smmu_domain);
 			return NULL;
 		}