Hi Lu,
On 11/5/18 8:34 AM, Lu Baolu wrote:
> When multiple domains per device has been enabled by the
> device driver, the device will tag the default PASID for
> the domain to all DMA traffics out of the subset of this
> device; and the IOMMU should translate the DMA requests
> in PASID granularity.
>
> This extends the intel_iommu_attach/detach_device() ops
> to support managing PASID granular translation structures
> when the device driver has enabled multiple domains per
> device.
>
> Cc: Ashok Raj <ashok.raj@xxxxxxxxx>
> Cc: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
> Cc: Kevin Tian <kevin.tian@xxxxxxxxx>
> Signed-off-by: Sanjay Kumar <sanjay.k.kumar@xxxxxxxxx>
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Signed-off-by: Liu Yi L <yi.l.liu@xxxxxxxxx>
> ---
> drivers/iommu/intel-iommu.c | 192 +++++++++++++++++++++++++++++++-----
> include/linux/intel-iommu.h | 10 ++
> 2 files changed, 180 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
> index 2c86ac71c774..a61b25ad0d3b 100644
> --- a/drivers/iommu/intel-iommu.c
> +++ b/drivers/iommu/intel-iommu.c
> @@ -2477,6 +2477,7 @@ static struct dmar_domain *dmar_insert_one_dev_info(struct intel_iommu *iommu,
> info->iommu = iommu;
> info->pasid_table = NULL;
> info->auxd_enabled = 0;
> + INIT_LIST_HEAD(&info->auxiliary_domains);
>
> if (dev && dev_is_pci(dev)) {
> struct pci_dev *pdev = to_pci_dev(info->dev);
> @@ -5010,35 +5011,134 @@ static void intel_iommu_domain_free(struct iommu_domain *domain)
> domain_exit(to_dmar_domain(domain));
> }
>
> -static int intel_iommu_attach_device(struct iommu_domain *domain,
> - struct device *dev)
> +/*
> + * Check whether a @domain will be attached to the @dev in the
> + * auxiliary mode.
> + */
> +static inline bool
> +is_device_attach_aux_domain(struct device *dev, struct iommu_domain *domain)
> {
> - struct dmar_domain *dmar_domain = to_dmar_domain(domain);
> - struct intel_iommu *iommu;
> - int addr_width;
> - u8 bus, devfn;
> + struct device_domain_info *info = dev->archdata.iommu;
>
> - if (device_is_rmrr_locked(dev)) {
> - dev_warn(dev, "Device is ineligible for IOMMU domain attach due to platform RMRR requirement. Contact your platform vendor.\n");
> - return -EPERM;
> - }
> + return info && info->auxd_enabled &&
> + domain->type == IOMMU_DOMAIN_UNMANAGED;
> +}
>
> - /* normally dev is not mapped */
> - if (unlikely(domain_context_mapped(dev))) {
> - struct dmar_domain *old_domain;
> +static void auxiliary_link_device(struct dmar_domain *domain,
> + struct device *dev)
> +{
> + struct device_domain_info *info = dev->archdata.iommu;
>
> - old_domain = find_domain(dev);
> - if (old_domain) {
> - rcu_read_lock();
> - dmar_remove_one_dev_info(old_domain, dev);
> - rcu_read_unlock();
> + assert_spin_locked(&device_domain_lock);
> + if (WARN_ON(!info))
> + return;
>
> - if (!domain_type_is_vm_or_si(old_domain) &&
> - list_empty(&old_domain->devices))
> - domain_exit(old_domain);
> + domain->auxd_refcnt++;
> + list_add(&domain->auxd, &info->auxiliary_domains);
> +}
> +
> +static void auxiliary_unlink_device(struct dmar_domain *domain,
> + struct device *dev)
> +{
> + struct device_domain_info *info = dev->archdata.iommu;
> +
> + assert_spin_locked(&device_domain_lock);
> + if (WARN_ON(!info))
> + return;
> +
> + list_del(&domain->auxd);
> + domain->auxd_refcnt--;
> +
> + if (!domain->auxd_refcnt && domain->default_pasid > 0)
> + intel_pasid_free_id(domain->default_pasid);
> +}
> +
> +static int domain_add_dev_auxd(struct dmar_domain *domain,
> + struct device *dev)
> +{
> + int ret;
> + u8 bus, devfn;
> + unsigned long flags;
> + struct intel_iommu *iommu;
> +
> + iommu = device_to_iommu(dev, &bus, &devfn);
> + if (!iommu)
> + return -ENODEV;
> +
> + spin_lock_irqsave(&device_domain_lock, flags);
> + if (domain->default_pasid <= 0) {
> + domain->default_pasid = intel_pasid_alloc_id(domain, PASID_MIN,
> + pci_max_pasids(to_pci_dev(dev)), GFP_ATOMIC);
> + if (domain->default_pasid < 0) {
> + pr_err("Can't allocate default pasid\n");
> + ret = -ENODEV;
> + goto pasid_failed;
> }
> }
>
> + spin_lock(&iommu->lock);
You may comment your nested lock policy somewhere.
> + ret = domain_attach_iommu(domain, iommu);
> + if (ret)
> + goto attach_failed;
> +
> + /* Setup the PASID entry for mediated devices: */
> + ret = intel_pasid_setup_second_level(iommu, domain, dev,
> + domain->default_pasid);
> + if (ret)
> + goto table_failed;
> + spin_unlock(&iommu->lock);
> +
> + auxiliary_link_device(domain, dev);
> +
> + spin_unlock_irqrestore(&device_domain_lock, flags);
> +
> + return 0;
> +
> +table_failed:
> + domain_detach_iommu(domain, iommu);
> +attach_failed:
> + spin_unlock(&iommu->lock);
> + if (!domain->auxd_refcnt && domain->default_pasid > 0)
> + intel_pasid_free_id(domain->default_pasid);
> +pasid_failed:
> + spin_unlock_irqrestore(&device_domain_lock, flags);
> +
> + return ret;
> +}
> +
> +static void domain_remove_dev_aux(struct dmar_domain *domain,
> + struct device *dev)
> +{
> + struct device_domain_info *info;
> + struct intel_iommu *iommu;
> + unsigned long flags;
> +
> + if (!is_device_attach_aux_domain(dev, &domain->domain))
> + return;
> +
> + spin_lock_irqsave(&device_domain_lock, flags);
> + info = dev->archdata.iommu;
> + iommu = info->iommu;
> +
> + intel_pasid_tear_down_entry(iommu, dev, domain->default_pasid);
> +
> + auxiliary_unlink_device(domain, dev);
> +
> + spin_lock(&iommu->lock);
> + domain_detach_iommu(domain, iommu);
> + spin_unlock(&iommu->lock);
> +
> + spin_unlock_irqrestore(&device_domain_lock, flags);
> +}
> +
> +static int __intel_iommu_attach_device(struct iommu_domain *domain,
> + struct device *dev)
> +{
Maybe introducing __intel_iommu_attach_device in a patch prior to that
one would help the review.
> + struct dmar_domain *dmar_domain = to_dmar_domain(domain);
> + struct intel_iommu *iommu;
> + int addr_width;
> + u8 bus, devfn;
> +
> iommu = device_to_iommu(dev, &bus, &devfn);
> if (!iommu)
> return -ENODEV;
> @@ -5071,7 +5171,47 @@ static int intel_iommu_attach_device(struct iommu_domain *domain,
> dmar_domain->agaw--;
> }
>
> - return domain_add_dev_info(dmar_domain, dev);
> + if (is_device_attach_aux_domain(dev, domain))
> + return domain_add_dev_auxd(dmar_domain, dev);
why not putting this directly into intel_iommu_attach_device_aux()?
> + else
> + return domain_add_dev_info(dmar_domain, dev);
and this into intel_iommu_attach_device() as
__intel_iommu_attach_device() is the common part now?
> +}
> +
> +static int intel_iommu_attach_device(struct iommu_domain *domain,
> + struct device *dev)
> +{
> + if (device_is_rmrr_locked(dev)) {
> + dev_warn(dev, "Device is ineligible for IOMMU domain attach due to platform RMRR requirement. Contact your platform vendor.\n");
> + return -EPERM;
> + }
shouldn't we test this in the common part (ie. in
__intel_iommu_attach_device). Don't RMRR also impact aux domains ?
> +
> + if (is_device_attach_aux_domain(dev, domain))
> + return -EPERM;
> +
> + /* normally dev is not mapped */
> + if (unlikely(domain_context_mapped(dev))) {
> + struct dmar_domain *old_domain;
> +
> + old_domain = find_domain(dev);
> + if (old_domain) {
> + rcu_read_lock();
> + dmar_remove_one_dev_info(old_domain, dev);
> + rcu_read_unlock();
> +
> + if (!domain_type_is_vm_or_si(old_domain) &&
> + list_empty(&old_domain->devices))
> + domain_exit(old_domain);
> + }
> + }
> +
> + return __intel_iommu_attach_device(domain, dev);
> +}
> +
> +static int intel_iommu_attach_device_aux(struct iommu_domain *domain,
> + struct device *dev)
> +{
> + return is_device_attach_aux_domain(dev, domain) ?
> + __intel_iommu_attach_device(domain, dev) : -EPERM;
> }
>
> static void intel_iommu_detach_device(struct iommu_domain *domain,
> @@ -5080,6 +5220,12 @@ static void intel_iommu_detach_device(struct iommu_domain *domain,
> dmar_remove_one_dev_info(to_dmar_domain(domain), dev);
> }
>
> +static void intel_iommu_detach_device_aux(struct iommu_domain *domain,
> + struct device *dev)
> +{
> + domain_remove_dev_aux(to_dmar_domain(domain), dev);
> +}
> +
> static int intel_iommu_map(struct iommu_domain *domain,
> unsigned long iova, phys_addr_t hpa,
> size_t size, int iommu_prot)
> @@ -5436,6 +5582,8 @@ const struct iommu_ops intel_iommu_ops = {
> .domain_free = intel_iommu_domain_free,
> .attach_dev = intel_iommu_attach_device,
> .detach_dev = intel_iommu_detach_device,
> + .attach_dev_aux = intel_iommu_attach_device_aux,
> + .detach_dev_aux = intel_iommu_detach_device_aux,
> .map = intel_iommu_map,
> .unmap = intel_iommu_unmap,
> .iova_to_phys = intel_iommu_iova_to_phys,
> diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
> index 6b198e13e75e..678c7fb05e74 100644
> --- a/include/linux/intel-iommu.h
> +++ b/include/linux/intel-iommu.h
> @@ -473,9 +473,11 @@ struct dmar_domain {
> /* Domain ids per IOMMU. Use u16 since
> * domain ids are 16 bit wide according
> * to VT-d spec, section 9.3 */
> + unsigned int auxd_refcnt; /* Refcount of auxiliary attaching */
>
> bool has_iotlb_device;
> struct list_head devices; /* all devices' list */
> + struct list_head auxd; /* link to device's auxiliary list */
> struct iova_domain iovad; /* iova's that belong to this domain */
>
> struct dma_pte *pgd; /* virtual address */
> @@ -494,6 +496,11 @@ struct dmar_domain {
> 2 == 1GiB, 3 == 512GiB, 4 == 1TiB */
> u64 max_addr; /* maximum mapped address */
>
> + int default_pasid; /*
> + * The default pasid used for non-SVM
> + * traffic on mediated devices.
> + */
> +
> struct iommu_domain domain; /* generic domain data structure for
> iommu core */
> };
> @@ -543,6 +550,9 @@ struct device_domain_info {
> struct list_head link; /* link to domain siblings */
> struct list_head global; /* link to global list */
> struct list_head table; /* link to pasid table */
> + struct list_head auxiliary_domains; /* auxiliary domains
> + * attached to this device
> + */
> u8 bus; /* PCI bus number */
> u8 devfn; /* PCI devfn number */
> u16 pfsid; /* SRIOV physical function source ID */
>
Thanks
Eric
