2021-02-24 00:15:08

by Eric Auger

[permalink] [raw]
Subject: [PATCH v14 05/13] iommu/smmuv3: Implement attach/detach_pasid_table

On attach_pasid_table() we program STE S1 related info set
by the guest into the actual physical STEs. At minimum
we need to program the context descriptor GPA and compute
whether the stage1 is translated/bypassed or aborted.

On detach, the stage 1 config is unset and the abort flag is
unset.

Signed-off-by: Eric Auger <[email protected]>

---
v13 -> v14:
- on PASID table detach, reset the abort flag (Keqian)

v7 -> v8:
- remove smmu->features check, now done on domain finalize

v6 -> v7:
- check versions and comment the fact we don't need to take
into account s1dss and s1fmt
v3 -> v4:
- adapt to changes in iommu_pasid_table_config
- different programming convention at s1_cfg/s2_cfg/ste.abort

v2 -> v3:
- callback now is named set_pasid_table and struct fields
are laid out differently.

v1 -> v2:
- invalidate the STE before changing them
- hold init_mutex
- handle new fields
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 89 +++++++++++++++++++++
1 file changed, 89 insertions(+)

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 085a784dfaee..5579ec4fccc8 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2842,6 +2842,93 @@ static void arm_smmu_get_resv_regions(struct device *dev,
iommu_dma_get_resv_regions(dev, head);
}

+static int arm_smmu_attach_pasid_table(struct iommu_domain *domain,
+ struct iommu_pasid_table_config *cfg)
+{
+ struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+ struct arm_smmu_master *master;
+ struct arm_smmu_device *smmu;
+ unsigned long flags;
+ int ret = -EINVAL;
+
+ if (cfg->format != IOMMU_PASID_FORMAT_SMMUV3)
+ return -EINVAL;
+
+ if (cfg->version != PASID_TABLE_CFG_VERSION_1 ||
+ cfg->vendor_data.smmuv3.version != PASID_TABLE_SMMUV3_CFG_VERSION_1)
+ return -EINVAL;
+
+ mutex_lock(&smmu_domain->init_mutex);
+
+ smmu = smmu_domain->smmu;
+
+ if (!smmu)
+ goto out;
+
+ if (smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
+ goto out;
+
+ switch (cfg->config) {
+ case IOMMU_PASID_CONFIG_ABORT:
+ smmu_domain->s1_cfg.set = false;
+ smmu_domain->abort = true;
+ break;
+ case IOMMU_PASID_CONFIG_BYPASS:
+ smmu_domain->s1_cfg.set = false;
+ smmu_domain->abort = false;
+ break;
+ case IOMMU_PASID_CONFIG_TRANSLATE:
+ /* we do not support S1 <-> S1 transitions */
+ if (smmu_domain->s1_cfg.set)
+ goto out;
+
+ /*
+ * we currently support a single CD so s1fmt and s1dss
+ * fields are also ignored
+ */
+ if (cfg->pasid_bits)
+ goto out;
+
+ smmu_domain->s1_cfg.cdcfg.cdtab_dma = cfg->base_ptr;
+ smmu_domain->s1_cfg.set = true;
+ smmu_domain->abort = false;
+ break;
+ default:
+ goto out;
+ }
+ spin_lock_irqsave(&smmu_domain->devices_lock, flags);
+ list_for_each_entry(master, &smmu_domain->devices, domain_head)
+ arm_smmu_install_ste_for_dev(master);
+ spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
+ ret = 0;
+out:
+ mutex_unlock(&smmu_domain->init_mutex);
+ return ret;
+}
+
+static void arm_smmu_detach_pasid_table(struct iommu_domain *domain)
+{
+ struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
+ struct arm_smmu_master *master;
+ unsigned long flags;
+
+ mutex_lock(&smmu_domain->init_mutex);
+
+ if (smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
+ goto unlock;
+
+ smmu_domain->s1_cfg.set = false;
+ smmu_domain->abort = false;
+
+ spin_lock_irqsave(&smmu_domain->devices_lock, flags);
+ list_for_each_entry(master, &smmu_domain->devices, domain_head)
+ arm_smmu_install_ste_for_dev(master);
+ spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
+
+unlock:
+ mutex_unlock(&smmu_domain->init_mutex);
+}
+
static bool arm_smmu_dev_has_feature(struct device *dev,
enum iommu_dev_features feat)
{
@@ -2939,6 +3026,8 @@ static struct iommu_ops arm_smmu_ops = {
.of_xlate = arm_smmu_of_xlate,
.get_resv_regions = arm_smmu_get_resv_regions,
.put_resv_regions = generic_iommu_put_resv_regions,
+ .attach_pasid_table = arm_smmu_attach_pasid_table,
+ .detach_pasid_table = arm_smmu_detach_pasid_table,
.dev_has_feat = arm_smmu_dev_has_feature,
.dev_feat_enabled = arm_smmu_dev_feature_enabled,
.dev_enable_feat = arm_smmu_dev_enable_feature,
--
2.26.2


2021-03-04 06:06:22

by Keqian Zhu

[permalink] [raw]
Subject: Re: [PATCH v14 05/13] iommu/smmuv3: Implement attach/detach_pasid_table

Hi Eric,

On 2021/2/24 4:56, Eric Auger wrote:
> On attach_pasid_table() we program STE S1 related info set
> by the guest into the actual physical STEs. At minimum
> we need to program the context descriptor GPA and compute
> whether the stage1 is translated/bypassed or aborted.
>
> On detach, the stage 1 config is unset and the abort flag is
> unset.
>
> Signed-off-by: Eric Auger <[email protected]>
>
[...]

> +
> + /*
> + * we currently support a single CD so s1fmt and s1dss
> + * fields are also ignored
> + */
> + if (cfg->pasid_bits)
> + goto out;
> +
> + smmu_domain->s1_cfg.cdcfg.cdtab_dma = cfg->base_ptr;
only the "cdtab_dma" field of "cdcfg" is set, we are not able to locate a specific cd using arm_smmu_get_cd_ptr().

Maybe we'd better use a specialized function to fill other fields of "cdcfg" or add a sanity check in arm_smmu_get_cd_ptr()
to prevent calling it under nested mode?

As now we just call arm_smmu_get_cd_ptr() during finalise_s1(), no problem found. Just a suggestion ;-)

Thanks,
Keqian


> + smmu_domain->s1_cfg.set = true;
> + smmu_domain->abort = false;
> + break;
> + default:
> + goto out;
> + }
> + spin_lock_irqsave(&smmu_domain->devices_lock, flags);
> + list_for_each_entry(master, &smmu_domain->devices, domain_head)
> + arm_smmu_install_ste_for_dev(master);
> + spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
> + ret = 0;
> +out:
> + mutex_unlock(&smmu_domain->init_mutex);
> + return ret;
> +}
> +
> +static void arm_smmu_detach_pasid_table(struct iommu_domain *domain)
> +{
> + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
> + struct arm_smmu_master *master;
> + unsigned long flags;
> +
> + mutex_lock(&smmu_domain->init_mutex);
> +
> + if (smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
> + goto unlock;
> +
> + smmu_domain->s1_cfg.set = false;
> + smmu_domain->abort = false;
> +
> + spin_lock_irqsave(&smmu_domain->devices_lock, flags);
> + list_for_each_entry(master, &smmu_domain->devices, domain_head)
> + arm_smmu_install_ste_for_dev(master);
> + spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
> +
> +unlock:
> + mutex_unlock(&smmu_domain->init_mutex);
> +}
> +
> static bool arm_smmu_dev_has_feature(struct device *dev,
> enum iommu_dev_features feat)
> {
> @@ -2939,6 +3026,8 @@ static struct iommu_ops arm_smmu_ops = {
> .of_xlate = arm_smmu_of_xlate,
> .get_resv_regions = arm_smmu_get_resv_regions,
> .put_resv_regions = generic_iommu_put_resv_regions,
> + .attach_pasid_table = arm_smmu_attach_pasid_table,
> + .detach_pasid_table = arm_smmu_detach_pasid_table,
> .dev_has_feat = arm_smmu_dev_has_feature,
> .dev_feat_enabled = arm_smmu_dev_feature_enabled,
> .dev_enable_feat = arm_smmu_dev_enable_feature,
>

2021-03-19 13:18:20

by Eric Auger

[permalink] [raw]
Subject: Re: [PATCH v14 05/13] iommu/smmuv3: Implement attach/detach_pasid_table

Hi Keqian,

On 3/2/21 9:35 AM, Keqian Zhu wrote:
> Hi Eric,
>
> On 2021/2/24 4:56, Eric Auger wrote:
>> On attach_pasid_table() we program STE S1 related info set
>> by the guest into the actual physical STEs. At minimum
>> we need to program the context descriptor GPA and compute
>> whether the stage1 is translated/bypassed or aborted.
>>
>> On detach, the stage 1 config is unset and the abort flag is
>> unset.
>>
>> Signed-off-by: Eric Auger <[email protected]>
>>
> [...]
>
>> +
>> + /*
>> + * we currently support a single CD so s1fmt and s1dss
>> + * fields are also ignored
>> + */
>> + if (cfg->pasid_bits)
>> + goto out;
>> +
>> + smmu_domain->s1_cfg.cdcfg.cdtab_dma = cfg->base_ptr;
> only the "cdtab_dma" field of "cdcfg" is set, we are not able to locate a specific cd using arm_smmu_get_cd_ptr().
>
> Maybe we'd better use a specialized function to fill other fields of "cdcfg" or add a sanity check in arm_smmu_get_cd_ptr()
> to prevent calling it under nested mode?
>
> As now we just call arm_smmu_get_cd_ptr() during finalise_s1(), no problem found. Just a suggestion ;-)

forgive me for the delay. yes I can indeed make sure that code is not
called in nested mode. Please could you detail why you would need to
call arm_smmu_get_cd_ptr()?

Thanks

Eric
>
> Thanks,
> Keqian
>
>
>> + smmu_domain->s1_cfg.set = true;
>> + smmu_domain->abort = false;
>> + break;
>> + default:
>> + goto out;
>> + }
>> + spin_lock_irqsave(&smmu_domain->devices_lock, flags);
>> + list_for_each_entry(master, &smmu_domain->devices, domain_head)
>> + arm_smmu_install_ste_for_dev(master);
>> + spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
>> + ret = 0;
>> +out:
>> + mutex_unlock(&smmu_domain->init_mutex);
>> + return ret;
>> +}
>> +
>> +static void arm_smmu_detach_pasid_table(struct iommu_domain *domain)
>> +{
>> + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
>> + struct arm_smmu_master *master;
>> + unsigned long flags;
>> +
>> + mutex_lock(&smmu_domain->init_mutex);
>> +
>> + if (smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
>> + goto unlock;
>> +
>> + smmu_domain->s1_cfg.set = false;
>> + smmu_domain->abort = false;
>> +
>> + spin_lock_irqsave(&smmu_domain->devices_lock, flags);
>> + list_for_each_entry(master, &smmu_domain->devices, domain_head)
>> + arm_smmu_install_ste_for_dev(master);
>> + spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
>> +
>> +unlock:
>> + mutex_unlock(&smmu_domain->init_mutex);
>> +}
>> +
>> static bool arm_smmu_dev_has_feature(struct device *dev,
>> enum iommu_dev_features feat)
>> {
>> @@ -2939,6 +3026,8 @@ static struct iommu_ops arm_smmu_ops = {
>> .of_xlate = arm_smmu_of_xlate,
>> .get_resv_regions = arm_smmu_get_resv_regions,
>> .put_resv_regions = generic_iommu_put_resv_regions,
>> + .attach_pasid_table = arm_smmu_attach_pasid_table,
>> + .detach_pasid_table = arm_smmu_detach_pasid_table,
>> .dev_has_feat = arm_smmu_dev_has_feature,
>> .dev_feat_enabled = arm_smmu_dev_feature_enabled,
>> .dev_enable_feat = arm_smmu_dev_enable_feature,
>>
>

2021-03-22 06:25:50

by Keqian Zhu

[permalink] [raw]
Subject: Re: [PATCH v14 05/13] iommu/smmuv3: Implement attach/detach_pasid_table

Hi Eric,

On 2021/3/19 21:15, Auger Eric wrote:
> Hi Keqian,
>
> On 3/2/21 9:35 AM, Keqian Zhu wrote:
>> Hi Eric,
>>
>> On 2021/2/24 4:56, Eric Auger wrote:
>>> On attach_pasid_table() we program STE S1 related info set
>>> by the guest into the actual physical STEs. At minimum
>>> we need to program the context descriptor GPA and compute
>>> whether the stage1 is translated/bypassed or aborted.
>>>
>>> On detach, the stage 1 config is unset and the abort flag is
>>> unset.
>>>
>>> Signed-off-by: Eric Auger <[email protected]>
>>>
>> [...]
>>
>>> +
>>> + /*
>>> + * we currently support a single CD so s1fmt and s1dss
>>> + * fields are also ignored
>>> + */
>>> + if (cfg->pasid_bits)
>>> + goto out;
>>> +
>>> + smmu_domain->s1_cfg.cdcfg.cdtab_dma = cfg->base_ptr;
>> only the "cdtab_dma" field of "cdcfg" is set, we are not able to locate a specific cd using arm_smmu_get_cd_ptr().
>>
>> Maybe we'd better use a specialized function to fill other fields of "cdcfg" or add a sanity check in arm_smmu_get_cd_ptr()
>> to prevent calling it under nested mode?
>>
>> As now we just call arm_smmu_get_cd_ptr() during finalise_s1(), no problem found. Just a suggestion ;-)
>
> forgive me for the delay. yes I can indeed make sure that code is not
> called in nested mode. Please could you detail why you would need to
> call arm_smmu_get_cd_ptr()?
I accidentally called this function in nested mode when verify the smmu mpam feature. :)

Yes, in nested mode, context descriptor is owned by guest, hypervisor does not need to care about its content.
Maybe we'd better give an explicit comment for arm_smmu_get_cd_ptr() to let coder pay attention to this? :)

Thanks,
Keqian

>
> Thanks
>
> Eric
>>
>> Thanks,
>> Keqian
>>
>>
>>> + smmu_domain->s1_cfg.set = true;
>>> + smmu_domain->abort = false;
>>> + break;
>>> + default:
>>> + goto out;
>>> + }
>>> + spin_lock_irqsave(&smmu_domain->devices_lock, flags);
>>> + list_for_each_entry(master, &smmu_domain->devices, domain_head)
>>> + arm_smmu_install_ste_for_dev(master);
>>> + spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
>>> + ret = 0;
>>> +out:
>>> + mutex_unlock(&smmu_domain->init_mutex);
>>> + return ret;
>>> +}
>>> +
>>> +static void arm_smmu_detach_pasid_table(struct iommu_domain *domain)
>>> +{
>>> + struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
>>> + struct arm_smmu_master *master;
>>> + unsigned long flags;
>>> +
>>> + mutex_lock(&smmu_domain->init_mutex);
>>> +
>>> + if (smmu_domain->stage != ARM_SMMU_DOMAIN_NESTED)
>>> + goto unlock;
>>> +
>>> + smmu_domain->s1_cfg.set = false;
>>> + smmu_domain->abort = false;
>>> +
>>> + spin_lock_irqsave(&smmu_domain->devices_lock, flags);
>>> + list_for_each_entry(master, &smmu_domain->devices, domain_head)
>>> + arm_smmu_install_ste_for_dev(master);
>>> + spin_unlock_irqrestore(&smmu_domain->devices_lock, flags);
>>> +
>>> +unlock:
>>> + mutex_unlock(&smmu_domain->init_mutex);
>>> +}
>>> +
>>> static bool arm_smmu_dev_has_feature(struct device *dev,
>>> enum iommu_dev_features feat)
>>> {
>>> @@ -2939,6 +3026,8 @@ static struct iommu_ops arm_smmu_ops = {
>>> .of_xlate = arm_smmu_of_xlate,
>>> .get_resv_regions = arm_smmu_get_resv_regions,
>>> .put_resv_regions = generic_iommu_put_resv_regions,
>>> + .attach_pasid_table = arm_smmu_attach_pasid_table,
>>> + .detach_pasid_table = arm_smmu_detach_pasid_table,
>>> .dev_has_feat = arm_smmu_dev_has_feature,
>>> .dev_feat_enabled = arm_smmu_dev_feature_enabled,
>>> .dev_enable_feat = arm_smmu_dev_enable_feature,
>>>
>>
>
> .
>