lkml.org 
[lkml]   [2018]   [Aug]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH v2 05/12] iommu/vt-d: Reserve a domain id for FL and PT modes
    Date
    Vt-d spec rev3.0 (section 6.2.3.1) requires that each pasid
    entry for first-level or pass-through translation should be
    programmed with a domain id different from those used for
    second-level or nested translation. It is recommended that
    software could use a same domain id for all first-only and
    pass-through translations.

    This reserves a domain id for first-level and pass-through
    translations.

    Cc: Ashok Raj <ashok.raj@intel.com>
    Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
    Cc: Kevin Tian <kevin.tian@intel.com>
    Cc: Liu Yi L <yi.l.liu@intel.com>
    Cc: Sanjay Kumar <sanjay.k.kumar@intel.com>
    Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
    ---
    drivers/iommu/intel-iommu.c | 10 ++++++++++
    drivers/iommu/intel-pasid.h | 6 ++++++
    2 files changed, 16 insertions(+)

    diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
    index 93cde957adc7..562da10bf93e 100644
    --- a/drivers/iommu/intel-iommu.c
    +++ b/drivers/iommu/intel-iommu.c
    @@ -1643,6 +1643,16 @@ static int iommu_init_domains(struct intel_iommu *iommu)
    */
    set_bit(0, iommu->domain_ids);

    + /*
    + * Vt-d spec rev3.0 (section 6.2.3.1) requires that each pasid
    + * entry for first-level or pass-through translation modes should
    + * be programmed with a domain id different from those used for
    + * second-level or nested translation. We reserve a domain id for
    + * this purpose.
    + */
    + if (sm_supported(iommu))
    + set_bit(FLPT_DEFAULT_DID, iommu->domain_ids);
    +
    return 0;
    }

    diff --git a/drivers/iommu/intel-pasid.h b/drivers/iommu/intel-pasid.h
    index 12f480c2bb8b..03c1612d173c 100644
    --- a/drivers/iommu/intel-pasid.h
    +++ b/drivers/iommu/intel-pasid.h
    @@ -17,6 +17,12 @@
    #define PDE_PFN_MASK PAGE_MASK
    #define PASID_PDE_SHIFT 6

    +/*
    + * Domain ID reserved for pasid entries programmed for first-level
    + * only and pass-through transfer modes.
    + */
    +#define FLPT_DEFAULT_DID 1
    +
    struct pasid_dir_entry {
    u64 val;
    };
    --
    2.17.1
    \
     
     \ /
      Last update: 2018-08-30 03:38    [W:2.874 / U:0.004 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site