Messages in this thread | | | Subject | Re: [PATCH v3 6/8] iommu/vt-d: Replace Intel specific PASID allocator with IOASID | From | Auger Eric <> | Date | Wed, 20 Nov 2019 22:06:24 +0100 |
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Hi Jacob,
On 11/19/19 6:56 PM, Jacob Pan wrote: > Make use of generic IOASID code to manage PASID allocation, > free, and lookup. Replace Intel specific code. > IOASID allocator is inclusive for both start and end of the allocation > range. The current code is based on IDR, which is exclusive for > the end of the allocation range. This patch fixes the off-by-one > error in intel_svm_bind_mm, where pasid_max - 1 is used for the end of > allocation range. no more as this is handled in 5/8 > > Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> > Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com> > Acked-by: Lu Baolu <baolu.lu@linux.intel.com> > --- > drivers/iommu/Kconfig | 1 + > drivers/iommu/intel-iommu.c | 13 +++++++------ > drivers/iommu/intel-pasid.c | 36 ------------------------------------ > drivers/iommu/intel-svm.c | 39 +++++++++++++++++++++++++-------------- > 4 files changed, 33 insertions(+), 56 deletions(-) > > diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig > index fd50ddffffbf..43ce450a40d3 100644 > --- a/drivers/iommu/Kconfig > +++ b/drivers/iommu/Kconfig > @@ -212,6 +212,7 @@ config INTEL_IOMMU_SVM > depends on INTEL_IOMMU && X86 > select PCI_PASID > select MMU_NOTIFIER > + select IOASID > help > Shared Virtual Memory (SVM) provides a facility for devices > to access DMA resources through process address space by > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c > index d598168e410d..a84f0caa33a0 100644 > --- a/drivers/iommu/intel-iommu.c > +++ b/drivers/iommu/intel-iommu.c > @@ -5238,7 +5238,7 @@ static void auxiliary_unlink_device(struct dmar_domain *domain, > domain->auxd_refcnt--; > > if (!domain->auxd_refcnt && domain->default_pasid > 0) > - intel_pasid_free_id(domain->default_pasid); > + ioasid_free(domain->default_pasid); > } > > static int aux_domain_add_dev(struct dmar_domain *domain, > @@ -5256,10 +5256,11 @@ static int aux_domain_add_dev(struct dmar_domain *domain, > if (domain->default_pasid <= 0) { > int pasid; > > - pasid = intel_pasid_alloc_id(domain, PASID_MIN, > - pci_max_pasids(to_pci_dev(dev)), > - GFP_KERNEL); > - if (pasid <= 0) { > + /* No private data needed for the default pasid */ > + pasid = ioasid_alloc(NULL, PASID_MIN, > + pci_max_pasids(to_pci_dev(dev)) - 1, > + NULL); > + if (pasid == INVALID_IOASID) { > pr_err("Can't allocate default pasid\n"); > return -ENODEV; > } > @@ -5295,7 +5296,7 @@ static int aux_domain_add_dev(struct dmar_domain *domain, > spin_unlock(&iommu->lock); > spin_unlock_irqrestore(&device_domain_lock, flags); > if (!domain->auxd_refcnt && domain->default_pasid > 0) > - intel_pasid_free_id(domain->default_pasid); > + ioasid_free(domain->default_pasid); > > return ret; > } > diff --git a/drivers/iommu/intel-pasid.c b/drivers/iommu/intel-pasid.c > index 732bfee228df..3cb569e76642 100644 > --- a/drivers/iommu/intel-pasid.c > +++ b/drivers/iommu/intel-pasid.c > @@ -26,42 +26,6 @@ > */ > static DEFINE_SPINLOCK(pasid_lock); > u32 intel_pasid_max_id = PASID_MAX; > -static DEFINE_IDR(pasid_idr); > - > -int intel_pasid_alloc_id(void *ptr, int start, int end, gfp_t gfp) > -{ > - int ret, min, max; > - > - min = max_t(int, start, PASID_MIN); > - max = min_t(int, end, intel_pasid_max_id); > - > - WARN_ON(in_interrupt()); > - idr_preload(gfp); > - spin_lock(&pasid_lock); > - ret = idr_alloc(&pasid_idr, ptr, min, max, GFP_ATOMIC); > - spin_unlock(&pasid_lock); > - idr_preload_end(); > - > - return ret; > -} > - > -void intel_pasid_free_id(int pasid) > -{ > - spin_lock(&pasid_lock); > - idr_remove(&pasid_idr, pasid); > - spin_unlock(&pasid_lock); > -} > - > -void *intel_pasid_lookup_id(int pasid) > -{ > - void *p; > - > - spin_lock(&pasid_lock); > - p = idr_find(&pasid_idr, pasid); > - spin_unlock(&pasid_lock); > - > - return p; > -} > > /* > * Per device pasid table management: > diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c > index e90d0b914afe..71b85b892c56 100644 > --- a/drivers/iommu/intel-svm.c > +++ b/drivers/iommu/intel-svm.c > @@ -17,6 +17,7 @@ > #include <linux/dmar.h> > #include <linux/interrupt.h> > #include <linux/mm_types.h> > +#include <linux/ioasid.h> > #include <asm/page.h> > > #include "intel-pasid.h" > @@ -335,16 +336,15 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_ > if (pasid_max > intel_pasid_max_id) > pasid_max = intel_pasid_max_id; > > - /* Do not use PASID 0 in caching mode (virtualised IOMMU) */ > - ret = intel_pasid_alloc_id(svm, > - !!cap_caching_mode(iommu->cap), > - pasid_max, GFP_KERNEL); > - if (ret < 0) { > + /* Do not use PASID 0, reserved for RID to PASID */ > + svm->pasid = ioasid_alloc(NULL, PASID_MIN, > + pasid_max - 1, svm); > + if (svm->pasid == INVALID_IOASID) { > kfree(svm); > kfree(sdev); > + ret = -ENOSPC; > goto out; > } > - svm->pasid = ret; > svm->notifier.ops = &intel_mmuops; > svm->mm = mm; > svm->flags = flags; > @@ -354,7 +354,7 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_ > if (mm) { > ret = mmu_notifier_register(&svm->notifier, mm); > if (ret) { > - intel_pasid_free_id(svm->pasid); > + ioasid_free(svm->pasid); > kfree(svm); > kfree(sdev); > goto out; > @@ -370,7 +370,7 @@ int intel_svm_bind_mm(struct device *dev, int *pasid, int flags, struct svm_dev_ > if (ret) { > if (mm) > mmu_notifier_unregister(&svm->notifier, mm); > - intel_pasid_free_id(svm->pasid); > + ioasid_free(svm->pasid); > kfree(svm); > kfree(sdev); > goto out; > @@ -418,7 +418,15 @@ int intel_svm_unbind_mm(struct device *dev, int pasid) > if (!iommu) > goto out; > > - svm = intel_pasid_lookup_id(pasid); > + svm = ioasid_find(NULL, pasid, NULL); > + if (!svm) > + goto out; > + > + if (IS_ERR(svm)) { > + ret = PTR_ERR(svm); > + goto out; > + } > + > if (!svm) > goto out; > > @@ -440,7 +448,7 @@ int intel_svm_unbind_mm(struct device *dev, int pasid) > kfree_rcu(sdev, rcu); > > if (list_empty(&svm->devs)) { > - intel_pasid_free_id(svm->pasid); > + ioasid_free(svm->pasid); > if (svm->mm) > mmu_notifier_unregister(&svm->notifier, svm->mm); > > @@ -475,10 +483,14 @@ int intel_svm_is_pasid_valid(struct device *dev, int pasid) > if (!iommu) > goto out; > > - svm = intel_pasid_lookup_id(pasid); > + svm = ioasid_find(NULL, pasid, NULL); > if (!svm) > goto out; > > + if (IS_ERR(svm)) { > + ret = PTR_ERR(svm); > + goto out; > + } > /* init_mm is used in this case */ > if (!svm->mm) > ret = 1; > @@ -585,13 +597,12 @@ static irqreturn_t prq_event_thread(int irq, void *d) > > if (!svm || svm->pasid != req->pasid) { > rcu_read_lock(); > - svm = intel_pasid_lookup_id(req->pasid); > + svm = ioasid_find(NULL, req->pasid, NULL); > /* It *can't* go away, because the driver is not permitted > * to unbind the mm while any page faults are outstanding. > * So we only need RCU to protect the internal idr code. */ > rcu_read_unlock(); > - > - if (!svm) { > + if (IS_ERR_OR_NULL(svm)) { > pr_err("%s: Page request for invalid PASID %d: %08llx %08llx\n", > iommu->name, req->pasid, ((unsigned long long *)req)[0], > ((unsigned long long *)req)[1]); > Besides Reviewed-by: Eric Auger <eric.auger@redhat.com>
Thanks
Eric
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