Messages in this thread | | | Subject | Re: [PATCH v2 11/19] iommu/vt-d: Replace Intel specific PASID allocator with IOASID | From | Auger Eric <> | Date | Sat, 27 Apr 2019 10:38:46 +0200 |
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On 4/26/19 11:01 PM, Jacob Pan wrote: > On Thu, 25 Apr 2019 12:04:01 +0200 > Auger Eric <eric.auger@redhat.com> wrote: > >> Hi Jacob, >> >> On 4/24/19 1:31 AM, Jacob Pan wrote: >>> Make use of generic IOASID code to manage PASID allocation, >>> free, and lookup. >>> >>> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> >>> --- >>> drivers/iommu/Kconfig | 1 + >>> drivers/iommu/intel-iommu.c | 9 ++++----- >>> drivers/iommu/intel-pasid.c | 36 >>> ------------------------------------ drivers/iommu/intel-svm.c | >>> 41 ++++++++++++++++++++++++----------------- 4 files changed, 29 >>> insertions(+), 58 deletions(-) >>> >>> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig >>> index 6f07f3b..7f92009 100644 >>> --- a/drivers/iommu/Kconfig >>> +++ b/drivers/iommu/Kconfig >>> @@ -204,6 +204,7 @@ config INTEL_IOMMU_SVM >>> bool "Support for Shared Virtual Memory with Intel IOMMU" >>> depends on INTEL_IOMMU && X86 >>> select PCI_PASID >>> + select IOASID >>> select MMU_NOTIFIER >>> help >>> Shared Virtual Memory (SVM) provides a facility for >>> devices diff --git a/drivers/iommu/intel-iommu.c >>> b/drivers/iommu/intel-iommu.c index ec6f22d..785330a 100644 >>> --- a/drivers/iommu/intel-iommu.c >>> +++ b/drivers/iommu/intel-iommu.c >>> @@ -5153,7 +5153,7 @@ 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, >>> @@ -5171,9 +5171,8 @@ 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); >>> + pasid = ioasid_alloc(NULL, PASID_MIN, >>> pci_max_pasids(to_pci_dev(dev)) - 1, >>> + domain); >>> if (pasid <= 0) { >> ioasid_t is a uint and returns INVALID_IOASID on error. Wouldn't it be >> simpler to make ioasid_alloc return an int? > Well, I think we still want the full uint range - 1(INVALID_IOASID). > Intel uses 20bit but I think SMMUs use 32 bits for streamID? I > should just check > if (pasid == INVALID_IOASID) { Jean-Philippe may correct me but SMMU uses 20b SubstreamId which is a superset of PASIDs. StreamId is 32b. > >>> pr_err("Can't allocate default pasid\n"); >>> return -ENODEV; >>> @@ -5210,7 +5209,7 @@ 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 5b1d3be..d339e8f 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..8fff212 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" >>> @@ -211,7 +212,9 @@ static void intel_mm_release(struct >>> mmu_notifier *mn, struct mm_struct *mm) rcu_read_lock(); >>> list_for_each_entry_rcu(sdev, &svm->devs, list) { >>> intel_pasid_tear_down_entry(svm->iommu, sdev->dev, >>> svm->pasid); >>> - intel_flush_svm_range_dev(svm, sdev, 0, -1, >>> 0, !svm->mm)> + /* for emulated iommu, PASID cache >>> invalidation implies IOTLB/DTLB */ >>> + if (!cap_caching_mode(svm->iommu->cap)) >>> + intel_flush_svm_range_dev(svm, sdev, 0, >>> -1, 0, !svm->mm); >> This change is not documented in the commit message. Isn't it a >> separate fix? > right, should be separate. > >>> } >>> rcu_read_unlock(); >>> >>> @@ -332,16 +335,15 @@ 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); >> the fact the max is not decremented compared to intel_pasid_alloc_id >> looks suspicious to me (exclusive to inclusive move). I guess it is a >> fix in which case this may be documented in the commit msg? > Yes, it should be in separate patch. > > VT-d will always support device with full 20bit PASID range only, we > should fail svm_bind if device pasid_max < 20. It has to be > included in this series otherwise we could have assigned a device with < > 20 PASID and our virtual command can only handle full 20bit. OK
Thanks
Eric > >>> + if (svm->pasid == INVALID_IOASID) { >>> kfree(svm); >>> kfree(sdev); >>> + ret = ENOSPC; >> -ENOSPC >>> goto out; >>> } >>> - svm->pasid = ret; >>> svm->notifier.ops = &intel_mmuops; >>> svm->mm = mm; >>> svm->flags = flags; >>> @@ -351,7 +353,7 @@ 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 +369,7 @@ 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); >> the ioasid_free returned value never is tested. Is it useful? >>> kfree(svm); >>> kfree(sdev); >>> goto out; >>> @@ -400,7 +402,12 @@ 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 +429,7 @@ 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 +464,11 @@ 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 +575,12 @@ 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]); >>> >> >> Thanks >> >> Eric > > [Jacob Pan] >
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