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 */