On Sun, 9 Jun 2019 06:44:15 -0700 Jacob Pan <[email protected]> wrote:
> Make use of generic IOASID code to manage PASID allocation, > free, and lookup. Replace Intel specific code. > > Signed-off-by: Jacob Pan <[email protected]> Hi Jacob, One question inline. Jonathan > --- > drivers/iommu/intel-iommu.c | 11 +++++------ > drivers/iommu/intel-pasid.c | 36 ------------------------------------ > drivers/iommu/intel-svm.c | 37 +++++++++++++++++++++---------------- > 3 files changed, 26 insertions(+), 58 deletions(-) > > diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c > index 5b84994..39b63fe 100644 > --- a/drivers/iommu/intel-iommu.c > +++ b/drivers/iommu/intel-iommu.c > @@ -5167,7 +5167,7 @@ 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, > @@ -5185,10 +5185,9 @@ 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) { > + pasid = ioasid_alloc(NULL, PASID_MIN, > pci_max_pasids(to_pci_dev(dev)) - 1, > + domain); Is there any point in passing the domain in as the private pointer here? I can't immediately see anywhere it is read back? It is also rather confusing as the same driver stashes two different types of data in the same xarray. > + if (pasid == INVALID_IOASID) { > pr_err("Can't allocate default pasid\n"); > return -ENODEV; > } > @@ -5224,7 +5223,7 @@ 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 69fddd3..1e25539 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; > -} > > int vcmd_alloc_pasid(struct intel_iommu *iommu, unsigned int *pasid) > { > diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c > index 8f87304..9cbcc1f 100644 > --- a/drivers/iommu/intel-svm.c > +++ b/drivers/iommu/intel-svm.c > @@ -25,6 +25,7 @@ > #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" > @@ -332,16 +333,15 @@ 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 - 1, 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; > @@ -351,7 +351,7 @@ 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; > @@ -367,7 +367,7 @@ 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; > @@ -400,7 +400,12 @@ 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 (IS_ERR(svm)) { > + ret = PTR_ERR(svm); > + goto out; > + } > + > if (!svm) > goto out; > > @@ -422,7 +427,7 @@ 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); > > @@ -457,10 +462,11 @@ int intel_svm_is_pasid_valid(struct device *dev, int > pasid) > if (!iommu) > goto out; > > - svm = intel_pasid_lookup_id(pasid); > - if (!svm) > + svm = ioasid_find(NULL, pasid, NULL); > + if (IS_ERR(svm)) { > + ret = PTR_ERR(svm); > goto out; > - > + } > /* init_mm is used in this case */ > if (!svm->mm) > ret = 1; > @@ -567,13 +573,12 @@ 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(svm) || !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]);
