Use it to store all vSMMU-related data. The vsid (Virtual Stream ID) will be the first use case. Then, add a rw_semaphore to protect it.
Also add a pair of arm_smmu_attach_prepare/commit_vmaster helpers to set or unset the master->vmaster point. Put these helpers inside the existing arm_smmu_attach_prepare/commit(). Note that identity and blocked ops don't call arm_smmu_attach_prepare/commit(), thus simply call the new helpers at the top, so a device attaching to an identity/blocked domain can unset the master->vmaster when the device is moving away from a nested domain.
Signed-off-by: Nicolin Chen nicolinc@nvidia.com --- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 23 +++++++++ .../arm/arm-smmu-v3/arm-smmu-v3-iommufd.c | 49 +++++++++++++++++++ drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 32 +++++++++++- 3 files changed, 103 insertions(+), 1 deletion(-)
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 bd9d7c85576a..4435ad7db776 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h @@ -799,6 +799,11 @@ struct arm_smmu_stream { struct rb_node node; };
+struct arm_smmu_vmaster { + struct arm_vsmmu *vsmmu; + unsigned long vsid; +}; + struct arm_smmu_event { u8 stall : 1, ssv : 1, @@ -824,6 +829,8 @@ struct arm_smmu_master { struct arm_smmu_device *smmu; struct device *dev; struct arm_smmu_stream *streams; + struct arm_smmu_vmaster *vmaster; + struct rw_semaphore vmaster_rwsem; /* Locked by the iommu core using the group mutex */ struct arm_smmu_ctx_desc_cfg cd_table; unsigned int num_streams; @@ -972,6 +979,7 @@ struct arm_smmu_attach_state { bool disable_ats; ioasid_t ssid; /* Resulting state */ + struct arm_smmu_vmaster *vmaster; bool ats_enabled; };
@@ -1055,9 +1063,24 @@ struct iommufd_viommu *arm_vsmmu_alloc(struct device *dev, struct iommu_domain *parent, struct iommufd_ctx *ictx, unsigned int viommu_type); +int arm_smmu_attach_prepare_vmaster(struct arm_smmu_attach_state *state, + struct iommu_domain *domain); +void arm_smmu_attach_commit_vmaster(struct arm_smmu_attach_state *state); #else #define arm_smmu_hw_info NULL #define arm_vsmmu_alloc NULL + +static inline int +arm_smmu_attach_prepare_vmaster(struct arm_smmu_attach_state *state, + struct iommu_domain *domain) +{ + return 0; /* NOP */ +} + +static inline void +arm_smmu_attach_commit_vmaster(struct arm_smmu_attach_state *state) +{ +} #endif /* CONFIG_ARM_SMMU_V3_IOMMUFD */
#endif /* _ARM_SMMU_V3_H */ diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c index c7cc613050d9..2b6253ef0e8f 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c @@ -85,6 +85,55 @@ static void arm_smmu_make_nested_domain_ste( } }
+int arm_smmu_attach_prepare_vmaster(struct arm_smmu_attach_state *state, + struct iommu_domain *domain) +{ + struct arm_smmu_nested_domain *nested_domain; + struct arm_smmu_vmaster *vmaster; + unsigned long vsid; + unsigned int cfg; + + iommu_group_mutex_assert(state->master->dev); + + if (domain->type != IOMMU_DOMAIN_NESTED) + return 0; + nested_domain = to_smmu_nested_domain(domain); + + /* Skip ABORT/BYPASS or invalid vSTE */ + cfg = FIELD_GET(STRTAB_STE_0_CFG, le64_to_cpu(nested_domain->ste[0])); + if (cfg == STRTAB_STE_0_CFG_ABORT || cfg == STRTAB_STE_0_CFG_BYPASS) + return 0; + if (!(nested_domain->ste[0] & cpu_to_le64(STRTAB_STE_0_V))) + return 0; + + vsid = iommufd_viommu_get_vdev_id(&nested_domain->vsmmu->core, + state->master->dev); + /* Fail the attach if vSID is not correct set by the user space */ + if (!vsid) + return -ENOENT; + + vmaster = kzalloc(sizeof(*vmaster), GFP_KERNEL); + if (!vmaster) + return -ENOMEM; + vmaster->vsmmu = nested_domain->vsmmu; + vmaster->vsid = vsid; + state->vmaster = vmaster; + + return 0; +} + +void arm_smmu_attach_commit_vmaster(struct arm_smmu_attach_state *state) +{ + struct arm_smmu_master *master = state->master; + + down_write(&master->vmaster_rwsem); + if (state->vmaster != master->vmaster) { + kfree(master->vmaster); + master->vmaster = state->vmaster; + } + up_write(&master->vmaster_rwsem); +} + static int arm_smmu_attach_dev_nested(struct iommu_domain *domain, struct device *dev) { 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 ea76f25c0661..686c171dd273 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -2802,6 +2802,7 @@ int arm_smmu_attach_prepare(struct arm_smmu_attach_state *state, struct arm_smmu_domain *smmu_domain = to_smmu_domain_devices(new_domain); unsigned long flags; + int ret;
/* * arm_smmu_share_asid() must not see two domains pointing to the same @@ -2831,9 +2832,15 @@ int arm_smmu_attach_prepare(struct arm_smmu_attach_state *state, }
if (smmu_domain) { + ret = arm_smmu_attach_prepare_vmaster(state, new_domain); + if (ret) + return ret; + master_domain = kzalloc(sizeof(*master_domain), GFP_KERNEL); - if (!master_domain) + if (!master_domain) { + kfree(state->vmaster); return -ENOMEM; + } master_domain->master = master; master_domain->ssid = state->ssid; if (new_domain->type == IOMMU_DOMAIN_NESTED) @@ -2860,6 +2867,7 @@ int arm_smmu_attach_prepare(struct arm_smmu_attach_state *state, spin_unlock_irqrestore(&smmu_domain->devices_lock, flags); kfree(master_domain); + kfree(state->vmaster); return -EINVAL; }
@@ -2892,6 +2900,8 @@ void arm_smmu_attach_commit(struct arm_smmu_attach_state *state)
lockdep_assert_held(&arm_smmu_asid_lock);
+ arm_smmu_attach_commit_vmaster(state); + if (state->ats_enabled && !master->ats_enabled) { arm_smmu_enable_ats(master); } else if (state->ats_enabled && master->ats_enabled) { @@ -3158,8 +3168,17 @@ static void arm_smmu_attach_dev_ste(struct iommu_domain *domain, static int arm_smmu_attach_dev_identity(struct iommu_domain *domain, struct device *dev) { + int ret; struct arm_smmu_ste ste; struct arm_smmu_master *master = dev_iommu_priv_get(dev); + struct arm_smmu_attach_state state = { + .master = master, + }; + + ret = arm_smmu_attach_prepare_vmaster(&state, domain); + if (ret) + return ret; + arm_smmu_attach_commit_vmaster(&state);
arm_smmu_make_bypass_ste(master->smmu, &ste); arm_smmu_attach_dev_ste(domain, dev, &ste, STRTAB_STE_1_S1DSS_BYPASS); @@ -3178,7 +3197,17 @@ static struct iommu_domain arm_smmu_identity_domain = { static int arm_smmu_attach_dev_blocked(struct iommu_domain *domain, struct device *dev) { + int ret; struct arm_smmu_ste ste; + struct arm_smmu_master *master = dev_iommu_priv_get(dev); + struct arm_smmu_attach_state state = { + .master = master, + }; + + ret = arm_smmu_attach_prepare_vmaster(&state, domain); + if (ret) + return ret; + arm_smmu_attach_commit_vmaster(&state);
arm_smmu_make_abort_ste(&ste); arm_smmu_attach_dev_ste(domain, dev, &ste, @@ -3428,6 +3457,7 @@ static struct iommu_device *arm_smmu_probe_device(struct device *dev)
master->dev = dev; master->smmu = smmu; + init_rwsem(&master->vmaster_rwsem); dev_iommu_priv_set(dev, master);
ret = arm_smmu_insert_master(smmu, master);