[PATCH AUTOSEL 6.11 127/244] iommu/arm-smmu-v3: Do not use devm for the cd table allocations

Sasha Levin sashal at kernel.org
Wed Sep 25 04:25:48 PDT 2024


From: Jason Gunthorpe <jgg at nvidia.com>

[ Upstream commit 47b2de35cab2b683f69d03515c2658c2d8515323 ]

The master->cd_table is entirely contained within the struct
arm_smmu_master which is guaranteed to be freed by the core code under
arm_smmu_release_device().

There is no reason to use devm here, arm_smmu_free_cd_tables() is reliably
called to free the CD related memory. Remove it and save some memory.

Tested-by: Nicolin Chen <nicolinc at nvidia.com>
Reviewed-by: Nicolin Chen <nicolinc at nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg at nvidia.com>
Link: https://lore.kernel.org/r/5-v4-6416877274e1+1af-smmuv3_tidy_jgg@nvidia.com
Signed-off-by: Will Deacon <will at kernel.org>
Signed-off-by: Sasha Levin <sashal at kernel.org>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 29 +++++++++------------
 1 file changed, 13 insertions(+), 16 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index a7d2a6b8a4980..8a419e88a920e 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -1185,8 +1185,8 @@ static int arm_smmu_alloc_cd_leaf_table(struct arm_smmu_device *smmu,
 {
 	size_t size = CTXDESC_L2_ENTRIES * (CTXDESC_CD_DWORDS << 3);
 
-	l1_desc->l2ptr = dmam_alloc_coherent(smmu->dev, size,
-					     &l1_desc->l2ptr_dma, GFP_KERNEL);
+	l1_desc->l2ptr = dma_alloc_coherent(smmu->dev, size,
+					    &l1_desc->l2ptr_dma, GFP_KERNEL);
 	if (!l1_desc->l2ptr) {
 		dev_warn(smmu->dev,
 			 "failed to allocate context descriptor table\n");
@@ -1400,17 +1400,17 @@ static int arm_smmu_alloc_cd_tables(struct arm_smmu_master *master)
 		cd_table->num_l1_ents = DIV_ROUND_UP(max_contexts,
 						  CTXDESC_L2_ENTRIES);
 
-		cd_table->l1_desc = devm_kcalloc(smmu->dev, cd_table->num_l1_ents,
-					      sizeof(*cd_table->l1_desc),
-					      GFP_KERNEL);
+		cd_table->l1_desc = kcalloc(cd_table->num_l1_ents,
+					    sizeof(*cd_table->l1_desc),
+					    GFP_KERNEL);
 		if (!cd_table->l1_desc)
 			return -ENOMEM;
 
 		l1size = cd_table->num_l1_ents * (CTXDESC_L1_DESC_DWORDS << 3);
 	}
 
-	cd_table->cdtab = dmam_alloc_coherent(smmu->dev, l1size, &cd_table->cdtab_dma,
-					   GFP_KERNEL);
+	cd_table->cdtab = dma_alloc_coherent(smmu->dev, l1size,
+					     &cd_table->cdtab_dma, GFP_KERNEL);
 	if (!cd_table->cdtab) {
 		dev_warn(smmu->dev, "failed to allocate context descriptor\n");
 		ret = -ENOMEM;
@@ -1421,7 +1421,7 @@ static int arm_smmu_alloc_cd_tables(struct arm_smmu_master *master)
 
 err_free_l1:
 	if (cd_table->l1_desc) {
-		devm_kfree(smmu->dev, cd_table->l1_desc);
+		kfree(cd_table->l1_desc);
 		cd_table->l1_desc = NULL;
 	}
 	return ret;
@@ -1441,21 +1441,18 @@ static void arm_smmu_free_cd_tables(struct arm_smmu_master *master)
 			if (!cd_table->l1_desc[i].l2ptr)
 				continue;
 
-			dmam_free_coherent(smmu->dev, size,
-					   cd_table->l1_desc[i].l2ptr,
-					   cd_table->l1_desc[i].l2ptr_dma);
+			dma_free_coherent(smmu->dev, size,
+					  cd_table->l1_desc[i].l2ptr,
+					  cd_table->l1_desc[i].l2ptr_dma);
 		}
-		devm_kfree(smmu->dev, cd_table->l1_desc);
-		cd_table->l1_desc = NULL;
+		kfree(cd_table->l1_desc);
 
 		l1size = cd_table->num_l1_ents * (CTXDESC_L1_DESC_DWORDS << 3);
 	} else {
 		l1size = cd_table->num_l1_ents * (CTXDESC_CD_DWORDS << 3);
 	}
 
-	dmam_free_coherent(smmu->dev, l1size, cd_table->cdtab, cd_table->cdtab_dma);
-	cd_table->cdtab_dma = 0;
-	cd_table->cdtab = NULL;
+	dma_free_coherent(smmu->dev, l1size, cd_table->cdtab, cd_table->cdtab_dma);
 }
 
 /* Stream table manipulation functions */
-- 
2.43.0




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