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| author | Jacob Pan <jacob.jun.pan@linux.intel.com> | 2016-12-06 10:14:23 -0800 |
|---|---|---|
| committer | Joerg Roedel <jroedel@suse.de> | 2017-01-04 15:18:57 +0100 |
| commit | 65ca7f5f7d1cdde6c25172fe6107cd16902f826f (patch) | |
| tree | 6fff0dccb8fcf28797336c23e973f7dfbd8a20a4 | |
| parent | aec0e86172a79eb5e44aff1055bb953fe4d47c59 (diff) | |
| download | linux-65ca7f5f7d1cdde6c25172fe6107cd16902f826f.tar.bz2 | |
iommu/vt-d: Fix pasid table size encoding
Different encodings are used to represent supported PASID bits
and number of PASID table entries.
The current code assigns ecap_pss directly to extended context
table entry PTS which is wrong and could result in writing
non-zero bits to the reserved fields. IOMMU fault reason
11 will be reported when reserved bits are nonzero.
This patch converts ecap_pss to extend context entry pts encoding
based on VT-d spec. Chapter 9.4 as follows:
- number of PASID bits = ecap_pss + 1
- number of PASID table entries = 2^(pts + 5)
Software assigned limit of pasid_max value is also respected to
match the allocation limitation of PASID table.
cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
cc: Ashok Raj <ashok.raj@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Tested-by: Mika Kuoppala <mika.kuoppala@intel.com>
Fixes: 2f26e0a9c9860 ('iommu/vt-d: Add basic SVM PASID support')
Signed-off-by: Joerg Roedel <jroedel@suse.de>
| -rw-r--r-- | drivers/iommu/intel-iommu.c | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 8862dc1e88eb..8a185250ae5a 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -5204,6 +5204,25 @@ static void intel_iommu_remove_device(struct device *dev) } #ifdef CONFIG_INTEL_IOMMU_SVM +#define MAX_NR_PASID_BITS (20) +static inline unsigned long intel_iommu_get_pts(struct intel_iommu *iommu) +{ + /* + * Convert ecap_pss to extend context entry pts encoding, also + * respect the soft pasid_max value set by the iommu. + * - number of PASID bits = ecap_pss + 1 + * - number of PASID table entries = 2^(pts + 5) + * Therefore, pts = ecap_pss - 4 + * e.g. KBL ecap_pss = 0x13, PASID has 20 bits, pts = 15 + */ + if (ecap_pss(iommu->ecap) < 5) + return 0; + + /* pasid_max is encoded as actual number of entries not the bits */ + return find_first_bit((unsigned long *)&iommu->pasid_max, + MAX_NR_PASID_BITS) - 5; +} + int intel_iommu_enable_pasid(struct intel_iommu *iommu, struct intel_svm_dev *sdev) { struct device_domain_info *info; @@ -5236,7 +5255,9 @@ int intel_iommu_enable_pasid(struct intel_iommu *iommu, struct intel_svm_dev *sd if (!(ctx_lo & CONTEXT_PASIDE)) { context[1].hi = (u64)virt_to_phys(iommu->pasid_state_table); - context[1].lo = (u64)virt_to_phys(iommu->pasid_table) | ecap_pss(iommu->ecap); + context[1].lo = (u64)virt_to_phys(iommu->pasid_table) | + intel_iommu_get_pts(iommu); + wmb(); /* CONTEXT_TT_MULTI_LEVEL and CONTEXT_TT_DEV_IOTLB are both * extended to permit requests-with-PASID if the PASIDE bit |