From: Jason Gunthorpe Date: Tue, 11 Jun 2024 00:31:10 +0000 (-0300) Subject: iommu/arm-smmu-v3: Do not zero the strtab twice X-Git-Tag: io_uring-6.11-20240722~23^2~8^2~1^2~12 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=c84c5ab76c9c04b5f1c8cc66ee9313198e89bb11;p=linux-2.6-block.git iommu/arm-smmu-v3: Do not zero the strtab twice dmam_alloc_coherent() already returns zero'd memory so cfg->strtab.l1_desc (the list of DMA addresses for the L2 entries) is already zero'd. arm_smmu_init_l1_strtab() goes through and calls arm_smmu_write_strtab_l1_desc() on the newly allocated (and zero'd) struct arm_smmu_strtab_l1_desc, which ends up computing 'val = 0' and zeroing it again. Remove arm_smmu_init_l1_strtab() and just call devm_kcalloc() from arm_smmu_init_strtab_2lvl to allocate the companion struct. Tested-by: Nicolin Chen Reviewed-by: Mostafa Saleh Signed-off-by: Jason Gunthorpe Reviewed-by: Nicolin Chen Link: https://lore.kernel.org/r/1-v2-318ed5f6983b+198f-smmuv3_tidy_jgg@nvidia.com Signed-off-by: Will Deacon --- 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 8c3031fe542b..bb2d9b0c0f63 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -3523,25 +3523,6 @@ static int arm_smmu_init_queues(struct arm_smmu_device *smmu) PRIQ_ENT_DWORDS, "priq"); } -static int arm_smmu_init_l1_strtab(struct arm_smmu_device *smmu) -{ - unsigned int i; - struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg; - void *strtab = smmu->strtab_cfg.strtab; - - cfg->l1_desc = devm_kcalloc(smmu->dev, cfg->num_l1_ents, - sizeof(*cfg->l1_desc), GFP_KERNEL); - if (!cfg->l1_desc) - return -ENOMEM; - - for (i = 0; i < cfg->num_l1_ents; ++i) { - arm_smmu_write_strtab_l1_desc(strtab, &cfg->l1_desc[i]); - strtab += STRTAB_L1_DESC_DWORDS << 3; - } - - return 0; -} - static int arm_smmu_init_strtab_2lvl(struct arm_smmu_device *smmu) { void *strtab; @@ -3577,7 +3558,12 @@ static int arm_smmu_init_strtab_2lvl(struct arm_smmu_device *smmu) reg |= FIELD_PREP(STRTAB_BASE_CFG_SPLIT, STRTAB_SPLIT); cfg->strtab_base_cfg = reg; - return arm_smmu_init_l1_strtab(smmu); + cfg->l1_desc = devm_kcalloc(smmu->dev, cfg->num_l1_ents, + sizeof(*cfg->l1_desc), GFP_KERNEL); + if (!cfg->l1_desc) + return -ENOMEM; + + return 0; } static int arm_smmu_init_strtab_linear(struct arm_smmu_device *smmu)