From: Jason Gunthorpe <jgg@nvidia.com> Introducing global statics which are of type struct iommu_domain, not struct arm_smmu_domain makes it difficult to retain arm_smmu_master->domain, as it can no longer point to an IDENTITY or BLOCKED domain. The only place that uses the value is arm_smmu_detach_dev(). Change things to work like other drivers and call iommu_get_domain_for_dev() to obtain the current domain. The master->domain is subtly protecting the master->domain_head against being unused as only PAGING domains will set master->domain and only paging domains use the master->domain_head. To make it simple keep the master->domain_head initialized so that the list_del() logic just does nothing for attached non-PAGING domains. Tested-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Tested-by: Nicolin Chen <nicolinc@nvidia.com> Tested-by: Moritz Fischer <moritzf@google.com> Reviewed-by: Nicolin Chen <nicolinc@nvidia.com> Reviewed-by: Mostafa Saleh <smostafa@google.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Link: https://lore.kernel.org/r/10-v6-96275f25c39d+2d4-smmuv3_newapi_p1_jgg@nvidia... Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 26 ++++++++------------- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 1 - 2 files changed, 10 insertions(+), 17 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 157be241db1b..7fc29d826600 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -2721,19 +2721,20 @@ static void arm_smmu_disable_pasid(struct arm_smmu_master *master) static void arm_smmu_detach_dev(struct arm_smmu_master *master) { + struct iommu_domain *domain = iommu_get_domain_for_dev(master->dev); + struct arm_smmu_domain *smmu_domain; unsigned long flags; - struct arm_smmu_domain *smmu_domain = master->domain; - if (!smmu_domain) + if (!domain) return; + smmu_domain = to_smmu_domain(domain); arm_smmu_disable_ats(master, smmu_domain); spin_lock_irqsave(&smmu_domain->devices_lock, flags); - list_del(&master->domain_head); + list_del_init(&master->domain_head); spin_unlock_irqrestore(&smmu_domain->devices_lock, flags); - master->domain = NULL; master->ats_enabled = false; } @@ -2787,8 +2788,6 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) arm_smmu_detach_dev(master); - master->domain = smmu_domain; - /* * The SMMU does not support enabling ATS with bypass. When the STE is * in bypass (STE.Config[2:0] == 0b100), ATS Translation Requests and @@ -2807,10 +2806,8 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) case ARM_SMMU_DOMAIN_S1: if (!master->cd_table.cdtab) { ret = arm_smmu_alloc_cd_tables(master); - if (ret) { - master->domain = NULL; + if (ret) goto out_list_del; - } } else { /* * arm_smmu_write_ctx_desc() relies on the entry being @@ -2818,17 +2815,13 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) */ ret = arm_smmu_write_ctx_desc(master, IOMMU_NO_PASID, NULL); - if (ret) { - master->domain = NULL; + if (ret) goto out_list_del; - } } ret = arm_smmu_write_ctx_desc(master, IOMMU_NO_PASID, &smmu_domain->cd); - if (ret) { - master->domain = NULL; + if (ret) goto out_list_del; - } arm_smmu_make_cdtable_ste(&target, master); arm_smmu_install_ste_for_dev(master, &target); @@ -2854,7 +2847,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev) out_list_del: spin_lock_irqsave(&smmu_domain->devices_lock, flags); - list_del(&master->domain_head); + list_del_init(&master->domain_head); spin_unlock_irqrestore(&smmu_domain->devices_lock, flags); out_unlock: @@ -3074,6 +3067,7 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev) master->dev = dev; master->smmu = smmu; INIT_LIST_HEAD(&master->bonds); + INIT_LIST_HEAD(&master->domain_head); dev_iommu_priv_set(dev, master); ret = arm_smmu_insert_master(smmu, master); diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h index a7f61b853e4c..f13557a84395 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h @@ -760,7 +760,6 @@ struct arm_smmu_stream { struct arm_smmu_master { struct arm_smmu_device *smmu; struct device *dev; - struct arm_smmu_domain *domain; struct list_head domain_head; struct arm_smmu_stream *streams; /* Locked by the iommu core using the group mutex */ -- 2.27.0