Messages in this thread | | | Date | Tue, 13 Aug 2019 09:57:23 -0700 | From | Jacob Pan <> | Subject | Re: [PATCH v4 13/22] iommu/vt-d: Enlightened PASID allocation |
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Hi Eric,
Apologize for the delayed response below,
On Tue, 16 Jul 2019 11:29:30 +0200 Auger Eric <eric.auger@redhat.com> wrote:
> Hi Jacob, > On 6/9/19 3:44 PM, Jacob Pan wrote: > > From: Lu Baolu <baolu.lu@linux.intel.com> > > > > If Intel IOMMU runs in caching mode, a.k.a. virtual IOMMU, the > > IOMMU driver should rely on the emulation software to allocate > > and free PASID IDs. The Intel vt-d spec revision 3.0 defines a > > register set to support this. This includes a capability register, > > a virtual command register and a virtual response register. Refer > > to section 10.4.42, 10.4.43, 10.4.44 for more information. > > > > This patch adds the enlightened PASID allocation/free interfaces > > via the virtual command register.> > > Cc: Ashok Raj <ashok.raj@intel.com> > > Cc: Jacob Pan <jacob.jun.pan@linux.intel.com> > > Cc: Kevin Tian <kevin.tian@intel.com> > > Signed-off-by: Liu Yi L <yi.l.liu@intel.com> > > Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> > > Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> > > --- > > drivers/iommu/intel-pasid.c | 76 > > +++++++++++++++++++++++++++++++++++++++++++++ > > drivers/iommu/intel-pasid.h | 13 +++++++- > > include/linux/intel-iommu.h | 2 ++ 3 files changed, 90 > > insertions(+), 1 deletion(-) > > > > diff --git a/drivers/iommu/intel-pasid.c > > b/drivers/iommu/intel-pasid.c index 2fefeaf..69fddd3 100644 > > --- a/drivers/iommu/intel-pasid.c > > +++ b/drivers/iommu/intel-pasid.c > > @@ -63,6 +63,82 @@ void *intel_pasid_lookup_id(int pasid) > > return p; > > } > > > > +int vcmd_alloc_pasid(struct intel_iommu *iommu, unsigned int > > *pasid) +{ > > + u64 res; > > + u64 cap; > > + u8 status_code; > > + unsigned long flags; > > + int ret = 0; > > + > > + if (!ecap_vcs(iommu->ecap)) { > > + pr_warn("IOMMU: %s: Hardware doesn't support > > virtual command\n", > > + iommu->name); > > + return -ENODEV; > > + } > > + > > + cap = dmar_readq(iommu->reg + DMAR_VCCAP_REG); > > + if (!(cap & DMA_VCS_PAS)) { > > + pr_warn("IOMMU: %s: Emulation software doesn't > > support PASID allocation\n", > > + iommu->name); > > + return -ENODEV; > > + } > > + > > + raw_spin_lock_irqsave(&iommu->register_lock, flags); > > + dmar_writeq(iommu->reg + DMAR_VCMD_REG, VCMD_CMD_ALLOC); > > + IOMMU_WAIT_OP(iommu, DMAR_VCRSP_REG, dmar_readq, > > + !(res & VCMD_VRSP_IP), res); > > + raw_spin_unlock_irqrestore(&iommu->register_lock, flags); > > + > > + status_code = VCMD_VRSP_SC(res); > > + switch (status_code) { > > + case VCMD_VRSP_SC_SUCCESS: > > + *pasid = VCMD_VRSP_RESULT(res); > > + break; > > + case VCMD_VRSP_SC_NO_PASID_AVAIL: > > + pr_info("IOMMU: %s: No PASID available\n", > > iommu->name); > > + ret = -ENOMEM; > > + break; > > + default: > > + ret = -ENODEV; > > + pr_warn("IOMMU: %s: Unkonwn error code %d\n", > unknown > s/unknown/unexpected sounds good. > > + iommu->name, status_code); > > + } > > + > > + return ret; > > +} > > + > > +void vcmd_free_pasid(struct intel_iommu *iommu, unsigned int pasid) > > +{ > > + u64 res; > > + u8 status_code; > > + unsigned long flags; > > + > > + if (!ecap_vcs(iommu->ecap)) { > > + pr_warn("IOMMU: %s: Hardware doesn't support > > virtual command\n", > > + iommu->name); > > + return; > > + } > Logically shouldn't you also check DMAR_VCCAP_REG as well? Good point, we may have more than just PASID allocation virtual commands. > > + > > + raw_spin_lock_irqsave(&iommu->register_lock, flags); > > + dmar_writeq(iommu->reg + DMAR_VCMD_REG, (pasid << 8) | > > VCMD_CMD_FREE); > > + IOMMU_WAIT_OP(iommu, DMAR_VCRSP_REG, dmar_readq, > > + !(res & VCMD_VRSP_IP), res); > > + raw_spin_unlock_irqrestore(&iommu->register_lock, flags); > > + > > + status_code = VCMD_VRSP_SC(res); > > + switch (status_code) { > > + case VCMD_VRSP_SC_SUCCESS: > > + break; > > + case VCMD_VRSP_SC_INVALID_PASID: > > + pr_info("IOMMU: %s: Invalid PASID\n", iommu->name); > > + break; > > + default: > > + pr_warn("IOMMU: %s: Unkonwn error code %d\n", > > + iommu->name, status_code); > s/Unkonwn/Unexpected will fix. > > + } > > +} > > + > > /* > > * Per device pasid table management: > > */ > > diff --git a/drivers/iommu/intel-pasid.h > > b/drivers/iommu/intel-pasid.h index 23537b3..4b26ab5 100644 > > --- a/drivers/iommu/intel-pasid.h > > +++ b/drivers/iommu/intel-pasid.h > > @@ -19,6 +19,16 @@ > > #define PASID_PDE_SHIFT 6 > > #define MAX_NR_PASID_BITS 20 > > > > +/* Virtual command interface for enlightened pasid management. */ > > +#define VCMD_CMD_ALLOC 0x1 > > +#define VCMD_CMD_FREE 0x2 > > +#define VCMD_VRSP_IP 0x1 > > +#define VCMD_VRSP_SC(e) (((e) >> 1) & 0x3) > > +#define VCMD_VRSP_SC_SUCCESS 0 > > +#define VCMD_VRSP_SC_NO_PASID_AVAIL 1 > > +#define VCMD_VRSP_SC_INVALID_PASID 1 > > +#define VCMD_VRSP_RESULT(e) (((e) >> 8) & 0xfffff) > > + > > /* > > * Domain ID reserved for pasid entries programmed for first-level > > * only and pass-through transfer modes. > > @@ -69,5 +79,6 @@ int intel_pasid_setup_pass_through(struct > > intel_iommu *iommu, struct device *dev, int pasid); > > void intel_pasid_tear_down_entry(struct intel_iommu *iommu, > > struct device *dev, int pasid); > > - > > +int vcmd_alloc_pasid(struct intel_iommu *iommu, unsigned int > > *pasid); +void vcmd_free_pasid(struct intel_iommu *iommu, unsigned > > int pasid); #endif /* __INTEL_PASID_H */ > > diff --git a/include/linux/intel-iommu.h > > b/include/linux/intel-iommu.h index 6925a18..bff907b 100644 > > --- a/include/linux/intel-iommu.h > > +++ b/include/linux/intel-iommu.h > > @@ -173,6 +173,7 @@ > > #define ecap_smpwc(e) (((e) >> 48) & 0x1) > > #define ecap_flts(e) (((e) >> 47) & 0x1) > > #define ecap_slts(e) (((e) >> 46) & 0x1) > > +#define ecap_vcs(e) (((e) >> 44) & 0x1) > > #define ecap_smts(e) (((e) >> 43) & 0x1) > > #define ecap_dit(e) ((e >> 41) & 0x1) > > #define ecap_pasid(e) ((e >> 40) & 0x1) > > @@ -289,6 +290,7 @@ > > > > /* PRS_REG */ > > #define DMA_PRS_PPR ((u32)1) > > +#define DMA_VCS_PAS ((u64)1) > > > > #define IOMMU_WAIT_OP(iommu, offset, op, cond, > > sts) \ do > > { > > \ > Otherwise > > Reviewed-by: Eric Auger <eric.auger@redhat.com> > > Thanks > > Eric >
[Jacob Pan]
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