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

Sasha Levin
2024-09-25T11:42:46Z

From: Jason Gunthorpe <jgg@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@nvidia.com>
Reviewed-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/5-v4-6416877274e1+1af-smmuv3_tidy_jgg@nvidia.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@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