diff options
| -rw-r--r-- | drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c | 5 | ||||
| -rw-r--r-- | drivers/iommu/intel/iommu.c | 4 | ||||
| -rw-r--r-- | drivers/iommu/intel/svm.c | 9 | ||||
| -rw-r--r-- | drivers/iommu/ioasid.c | 39 | ||||
| -rw-r--r-- | drivers/iommu/iommu-sva-lib.c | 39 | ||||
| -rw-r--r-- | drivers/iommu/iommu-sva-lib.h | 1 | ||||
| -rw-r--r-- | include/linux/ioasid.h | 12 | ||||
| -rw-r--r-- | include/linux/sched/mm.h | 16 | ||||
| -rw-r--r-- | kernel/fork.c | 1 |
9 files changed, 38 insertions, 88 deletions
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c index a737ba5f727e..22ddd05bbdcd 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-sva.c @@ -340,14 +340,12 @@ __arm_smmu_sva_bind(struct device *dev, struct mm_struct *mm) bond->smmu_mn = arm_smmu_mmu_notifier_get(smmu_domain, mm); if (IS_ERR(bond->smmu_mn)) { ret = PTR_ERR(bond->smmu_mn); - goto err_free_pasid; + goto err_free_bond; } list_add(&bond->list, &master->bonds); return &bond->sva; -err_free_pasid: - iommu_sva_free_pasid(mm); err_free_bond: kfree(bond); return ERR_PTR(ret); @@ -377,7 +375,6 @@ void arm_smmu_sva_unbind(struct iommu_sva *handle) if (refcount_dec_and_test(&bond->refs)) { list_del(&bond->list); arm_smmu_mmu_notifier_put(bond->smmu_mn); - iommu_sva_free_pasid(bond->mm); kfree(bond); } mutex_unlock(&sva_lock); diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 92fea3fbbb11..ef03b2176bbd 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4781,7 +4781,7 @@ attach_failed: link_failed: spin_unlock_irqrestore(&device_domain_lock, flags); if (list_empty(&domain->subdevices) && domain->default_pasid > 0) - ioasid_put(domain->default_pasid); + ioasid_free(domain->default_pasid); return ret; } @@ -4811,7 +4811,7 @@ static void aux_domain_remove_dev(struct dmar_domain *domain, spin_unlock_irqrestore(&device_domain_lock, flags); if (list_empty(&domain->subdevices) && domain->default_pasid > 0) - ioasid_put(domain->default_pasid); + ioasid_free(domain->default_pasid); } static int prepare_domain_attach_device(struct iommu_domain *domain, diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c index 5b5d69b04fcc..51ac2096b3da 100644 --- a/drivers/iommu/intel/svm.c +++ b/drivers/iommu/intel/svm.c @@ -514,11 +514,6 @@ static int intel_svm_alloc_pasid(struct device *dev, struct mm_struct *mm, return iommu_sva_alloc_pasid(mm, PASID_MIN, max_pasid - 1); } -static void intel_svm_free_pasid(struct mm_struct *mm) -{ - iommu_sva_free_pasid(mm); -} - static struct iommu_sva *intel_svm_bind_mm(struct intel_iommu *iommu, struct device *dev, struct mm_struct *mm, @@ -662,8 +657,6 @@ static int intel_svm_unbind_mm(struct device *dev, u32 pasid) kfree(svm); } } - /* Drop a PASID reference and free it if no reference. */ - intel_svm_free_pasid(mm); } out: return ret; @@ -1047,8 +1040,6 @@ struct iommu_sva *intel_svm_bind(struct device *dev, struct mm_struct *mm, void } sva = intel_svm_bind_mm(iommu, dev, mm, flags); - if (IS_ERR_OR_NULL(sva)) - intel_svm_free_pasid(mm); mutex_unlock(&pasid_mutex); return sva; diff --git a/drivers/iommu/ioasid.c b/drivers/iommu/ioasid.c index 06fee7416816..a786c034907c 100644 --- a/drivers/iommu/ioasid.c +++ b/drivers/iommu/ioasid.c @@ -2,7 +2,7 @@ /* * I/O Address Space ID allocator. There is one global IOASID space, split into * subsets. Users create a subset with DECLARE_IOASID_SET, then allocate and - * free IOASIDs with ioasid_alloc and ioasid_put. + * free IOASIDs with ioasid_alloc() and ioasid_free(). */ #include <linux/ioasid.h> #include <linux/module.h> @@ -15,7 +15,6 @@ struct ioasid_data { struct ioasid_set *set; void *private; struct rcu_head rcu; - refcount_t refs; }; /* @@ -315,7 +314,6 @@ ioasid_t ioasid_alloc(struct ioasid_set *set, ioasid_t min, ioasid_t max, data->set = set; data->private = private; - refcount_set(&data->refs, 1); /* * Custom allocator needs allocator data to perform platform specific @@ -348,35 +346,11 @@ exit_free: EXPORT_SYMBOL_GPL(ioasid_alloc); /** - * ioasid_get - obtain a reference to the IOASID - * @ioasid: the ID to get - */ -void ioasid_get(ioasid_t ioasid) -{ - struct ioasid_data *ioasid_data; - - spin_lock(&ioasid_allocator_lock); - ioasid_data = xa_load(&active_allocator->xa, ioasid); - if (ioasid_data) - refcount_inc(&ioasid_data->refs); - else - WARN_ON(1); - spin_unlock(&ioasid_allocator_lock); -} -EXPORT_SYMBOL_GPL(ioasid_get); - -/** - * ioasid_put - Release a reference to an ioasid + * ioasid_free - Free an ioasid * @ioasid: the ID to remove - * - * Put a reference to the IOASID, free it when the number of references drops to - * zero. - * - * Return: %true if the IOASID was freed, %false otherwise. */ -bool ioasid_put(ioasid_t ioasid) +void ioasid_free(ioasid_t ioasid) { - bool free = false; struct ioasid_data *ioasid_data; spin_lock(&ioasid_allocator_lock); @@ -386,10 +360,6 @@ bool ioasid_put(ioasid_t ioasid) goto exit_unlock; } - free = refcount_dec_and_test(&ioasid_data->refs); - if (!free) - goto exit_unlock; - active_allocator->ops->free(ioasid, active_allocator->ops->pdata); /* Custom allocator needs additional steps to free the xa element */ if (active_allocator->flags & IOASID_ALLOCATOR_CUSTOM) { @@ -399,9 +369,8 @@ bool ioasid_put(ioasid_t ioasid) exit_unlock: spin_unlock(&ioasid_allocator_lock); - return free; } -EXPORT_SYMBOL_GPL(ioasid_put); +EXPORT_SYMBOL_GPL(ioasid_free); /** * ioasid_find - Find IOASID data diff --git a/drivers/iommu/iommu-sva-lib.c b/drivers/iommu/iommu-sva-lib.c index bd41405d34e9..106506143896 100644 --- a/drivers/iommu/iommu-sva-lib.c +++ b/drivers/iommu/iommu-sva-lib.c @@ -18,8 +18,7 @@ static DECLARE_IOASID_SET(iommu_sva_pasid); * * Try to allocate a PASID for this mm, or take a reference to the existing one * provided it fits within the [@min, @max] range. On success the PASID is - * available in mm->pasid, and must be released with iommu_sva_free_pasid(). - * @min must be greater than 0, because 0 indicates an unused mm->pasid. + * available in mm->pasid and will be available for the lifetime of the mm. * * Returns 0 on success and < 0 on error. */ @@ -33,38 +32,24 @@ int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min, ioasid_t max) return -EINVAL; mutex_lock(&iommu_sva_lock); - if (mm->pasid) { - if (mm->pasid >= min && mm->pasid <= max) - ioasid_get(mm->pasid); - else + /* Is a PASID already associated with this mm? */ + if (pasid_valid(mm->pasid)) { + if (mm->pasid < min || mm->pasid >= max) ret = -EOVERFLOW; - } else { - pasid = ioasid_alloc(&iommu_sva_pasid, min, max, mm); - if (pasid == INVALID_IOASID) - ret = -ENOMEM; - else - mm->pasid = pasid; + goto out; } + + pasid = ioasid_alloc(&iommu_sva_pasid, min, max, mm); + if (!pasid_valid(pasid)) + ret = -ENOMEM; + else + mm_pasid_set(mm, pasid); +out: mutex_unlock(&iommu_sva_lock); return ret; } EXPORT_SYMBOL_GPL(iommu_sva_alloc_pasid); -/** - * iommu_sva_free_pasid - Release the mm's PASID - * @mm: the mm - * - * Drop one reference to a PASID allocated with iommu_sva_alloc_pasid() - */ -void iommu_sva_free_pasid(struct mm_struct *mm) -{ - mutex_lock(&iommu_sva_lock); - if (ioasid_put(mm->pasid)) - mm->pasid = 0; - mutex_unlock(&iommu_sva_lock); -} -EXPORT_SYMBOL_GPL(iommu_sva_free_pasid); - /* ioasid_find getter() requires a void * argument */ static bool __mmget_not_zero(void *mm) { diff --git a/drivers/iommu/iommu-sva-lib.h b/drivers/iommu/iommu-sva-lib.h index 95dc3ebc1928..8909ea1094e3 100644 --- a/drivers/iommu/iommu-sva-lib.h +++ b/drivers/iommu/iommu-sva-lib.h @@ -9,7 +9,6 @@ #include <linux/mm_types.h> int iommu_sva_alloc_pasid(struct mm_struct *mm, ioasid_t min, ioasid_t max); -void iommu_sva_free_pasid(struct mm_struct *mm); struct mm_struct *iommu_sva_find(ioasid_t pasid); /* I/O Page fault */ diff --git a/include/linux/ioasid.h b/include/linux/ioasid.h index 2237f64dbaae..af1c9d62e642 100644 --- a/include/linux/ioasid.h +++ b/include/linux/ioasid.h @@ -34,8 +34,7 @@ struct ioasid_allocator_ops { #if IS_ENABLED(CONFIG_IOASID) ioasid_t ioasid_alloc(struct ioasid_set *set, ioasid_t min, ioasid_t max, void *private); -void ioasid_get(ioasid_t ioasid); -bool ioasid_put(ioasid_t ioasid); +void ioasid_free(ioasid_t ioasid); void *ioasid_find(struct ioasid_set *set, ioasid_t ioasid, bool (*getter)(void *)); int ioasid_register_allocator(struct ioasid_allocator_ops *allocator); @@ -53,14 +52,7 @@ static inline ioasid_t ioasid_alloc(struct ioasid_set *set, ioasid_t min, return INVALID_IOASID; } -static inline void ioasid_get(ioasid_t ioasid) -{ -} - -static inline bool ioasid_put(ioasid_t ioasid) -{ - return false; -} +static inline void ioasid_free(ioasid_t ioasid) { } static inline void *ioasid_find(struct ioasid_set *set, ioasid_t ioasid, bool (*getter)(void *)) diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h index c74d1edbac2f..a80356e9dc69 100644 --- a/include/linux/sched/mm.h +++ b/include/linux/sched/mm.h @@ -439,8 +439,24 @@ static inline void mm_pasid_init(struct mm_struct *mm) { mm->pasid = INVALID_IOASID; } + +/* Associate a PASID with an mm_struct: */ +static inline void mm_pasid_set(struct mm_struct *mm, u32 pasid) +{ + mm->pasid = pasid; +} + +static inline void mm_pasid_drop(struct mm_struct *mm) +{ + if (pasid_valid(mm->pasid)) { + ioasid_free(mm->pasid); + mm->pasid = INVALID_IOASID; + } +} #else static inline void mm_pasid_init(struct mm_struct *mm) {} +static inline void mm_pasid_set(struct mm_struct *mm, u32 pasid) {} +static inline void mm_pasid_drop(struct mm_struct *mm) {} #endif #endif /* _LINUX_SCHED_MM_H */ diff --git a/kernel/fork.c b/kernel/fork.c index deacd2c17a7f..c03c6682464c 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1115,6 +1115,7 @@ static inline void __mmput(struct mm_struct *mm) } if (mm->binfmt) module_put(mm->binfmt->module); + mm_pasid_drop(mm); mmdrop(mm); } |