diff options
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_drv.h | 10 | ||||
| -rw-r--r-- | drivers/gpu/drm/i915/i915_gem_userptr.c | 409 |
2 files changed, 235 insertions, 184 deletions
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 7a830eac5ba3..3524306d8cfb 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -184,6 +184,7 @@ enum hpd_pin { if ((1 << (domain)) & (mask)) struct drm_i915_private; +struct i915_mm_struct; struct i915_mmu_object; enum intel_dpll_id { @@ -1506,9 +1507,8 @@ struct drm_i915_private { struct i915_gtt gtt; /* VM representing the global address space */ struct i915_gem_mm mm; -#if defined(CONFIG_MMU_NOTIFIER) - DECLARE_HASHTABLE(mmu_notifiers, 7); -#endif + DECLARE_HASHTABLE(mm_structs, 7); + struct mutex mm_lock; /* Kernel Modesetting */ @@ -1814,8 +1814,8 @@ struct drm_i915_gem_object { unsigned workers :4; #define I915_GEM_USERPTR_MAX_WORKERS 15 - struct mm_struct *mm; - struct i915_mmu_object *mn; + struct i915_mm_struct *mm; + struct i915_mmu_object *mmu_object; struct work_struct *work; } userptr; }; diff --git a/drivers/gpu/drm/i915/i915_gem_userptr.c b/drivers/gpu/drm/i915/i915_gem_userptr.c index fe69fc837d9e..d38413997379 100644 --- a/drivers/gpu/drm/i915/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/i915_gem_userptr.c @@ -32,6 +32,15 @@ #include <linux/mempolicy.h> #include <linux/swap.h> +struct i915_mm_struct { + struct mm_struct *mm; + struct drm_device *dev; + struct i915_mmu_notifier *mn; + struct hlist_node node; + struct kref kref; + struct work_struct work; +}; + #if defined(CONFIG_MMU_NOTIFIER) #include <linux/interval_tree.h> @@ -41,16 +50,12 @@ struct i915_mmu_notifier { struct mmu_notifier mn; struct rb_root objects; struct list_head linear; - struct drm_device *dev; - struct mm_struct *mm; - struct work_struct work; - unsigned long count; unsigned long serial; bool has_linear; }; struct i915_mmu_object { - struct i915_mmu_notifier *mmu; + struct i915_mmu_notifier *mn; struct interval_tree_node it; struct list_head link; struct drm_i915_gem_object *obj; @@ -96,18 +101,18 @@ static void *invalidate_range__linear(struct i915_mmu_notifier *mn, unsigned long start, unsigned long end) { - struct i915_mmu_object *mmu; + struct i915_mmu_object *mo; unsigned long serial; restart: serial = mn->serial; - list_for_each_entry(mmu, &mn->linear, link) { + list_for_each_entry(mo, &mn->linear, link) { struct drm_i915_gem_object *obj; - if (mmu->it.last < start || mmu->it.start > end) + if (mo->it.last < start || mo->it.start > end) continue; - obj = mmu->obj; + obj = mo->obj; drm_gem_object_reference(&obj->base); spin_unlock(&mn->lock); @@ -160,130 +165,47 @@ static const struct mmu_notifier_ops i915_gem_userptr_notifier = { }; static struct i915_mmu_notifier * -__i915_mmu_notifier_lookup(struct drm_device *dev, struct mm_struct *mm) -{ - struct drm_i915_private *dev_priv = to_i915(dev); - struct i915_mmu_notifier *mmu; - - /* Protected by dev->struct_mutex */ - hash_for_each_possible(dev_priv->mmu_notifiers, mmu, node, (unsigned long)mm) - if (mmu->mm == mm) - return mmu; - - return NULL; -} - -static struct i915_mmu_notifier * -i915_mmu_notifier_get(struct drm_device *dev, struct mm_struct *mm) +i915_mmu_notifier_create(struct mm_struct *mm) { - struct drm_i915_private *dev_priv = to_i915(dev); - struct i915_mmu_notifier *mmu; + struct i915_mmu_notifier *mn; int ret; - lockdep_assert_held(&dev->struct_mutex); - - mmu = __i915_mmu_notifier_lookup(dev, mm); - if (mmu) - return mmu; - - mmu = kmalloc(sizeof(*mmu), GFP_KERNEL); - if (mmu == NULL) + mn = kmalloc(sizeof(*mn), GFP_KERNEL); + if (mn == NULL) return ERR_PTR(-ENOMEM); - spin_lock_init(&mmu->lock); - mmu->dev = dev; - mmu->mn.ops = &i915_gem_userptr_notifier; - mmu->mm = mm; - mmu->objects = RB_ROOT; - mmu->count = 0; - mmu->serial = 1; - INIT_LIST_HEAD(&mmu->linear); - mmu->has_linear = false; - - /* Protected by mmap_sem (write-lock) */ - ret = __mmu_notifier_register(&mmu->mn, mm); + spin_lock_init(&mn->lock); + mn->mn.ops = &i915_gem_userptr_notifier; + mn->objects = RB_ROOT; + mn->serial = 1; + INIT_LIST_HEAD(&mn->linear); + mn->has_linear = false; + + /* Protected by mmap_sem (write-lock) */ + ret = __mmu_notifier_register(&mn->mn, mm); if (ret) { - kfree(mmu); + kfree(mn); return ERR_PTR(ret); } - /* Protected by dev->struct_mutex */ - hash_add(dev_priv->mmu_notifiers, &mmu->node, (unsigned long)mm); - return mmu; + return mn; } -static void -__i915_mmu_notifier_destroy_worker(struct work_struct *work) +static void __i915_mmu_notifier_update_serial(struct i915_mmu_notifier *mn) { - struct i915_mmu_notifier *mmu = container_of(work, typeof(*mmu), work); - mmu_notifier_unregister(&mmu->mn, mmu->mm); - kfree(mmu); -} - -static void -__i915_mmu_notifier_destroy(struct i915_mmu_notifier *mmu) -{ - lockdep_assert_held(&mmu->dev->struct_mutex); - - /* Protected by dev->struct_mutex */ - hash_del(&mmu->node); - - /* Our lock ordering is: mmap_sem, mmu_notifier_scru, struct_mutex. - * We enter the function holding struct_mutex, therefore we need - * to drop our mutex prior to calling mmu_notifier_unregister in - * order to prevent lock inversion (and system-wide deadlock) - * between the mmap_sem and struct-mutex. Hence we defer the - * unregistration to a workqueue where we hold no locks. - */ - INIT_WORK(&mmu->work, __i915_mmu_notifier_destroy_worker); - schedule_work(&mmu->work); -} - -static void __i915_mmu_notifier_update_serial(struct i915_mmu_notifier *mmu) -{ - if (++mmu->serial == 0) - mmu->serial = 1; -} - -static bool i915_mmu_notifier_has_linear(struct i915_mmu_notifier *mmu) -{ - struct i915_mmu_object *mn; - - list_for_each_entry(mn, &mmu->linear, link) - if (mn->is_linear) - return true; - - return false; -} - -static void -i915_mmu_notifier_del(struct i915_mmu_notifier *mmu, - struct i915_mmu_object *mn) -{ - lockdep_assert_held(&mmu->dev->struct_mutex); - - spin_lock(&mmu->lock); - list_del(&mn->link); - if (mn->is_linear) - mmu->has_linear = i915_mmu_notifier_has_linear(mmu); - else - interval_tree_remove(&mn->it, &mmu->objects); - __i915_mmu_notifier_update_serial(mmu); - spin_unlock(&mmu->lock); - - /* Protected against _add() by dev->struct_mutex */ - if (--mmu->count == 0) - __i915_mmu_notifier_destroy(mmu); + if (++mn->serial == 0) + mn->serial = 1; } static int -i915_mmu_notifier_add(struct i915_mmu_notifier *mmu, - struct i915_mmu_object *mn) +i915_mmu_notifier_add(struct drm_device *dev, + struct i915_mmu_notifier *mn, + struct i915_mmu_object *mo) { struct interval_tree_node *it; int ret; - ret = i915_mutex_lock_interruptible(mmu->dev); + ret = i915_mutex_lock_interruptible(dev); if (ret) return ret; @@ -291,11 +213,11 @@ i915_mmu_notifier_add(struct i915_mmu_notifier *mmu, * remove the objects from the interval tree) before we do * the check for overlapping objects. */ - i915_gem_retire_requests(mmu->dev); + i915_gem_retire_requests(dev); - spin_lock(&mmu->lock); - it = interval_tree_iter_first(&mmu->objects, - mn->it.start, mn->it.last); + spin_lock(&mn->lock); + it = interval_tree_iter_first(&mn->objects, + mo->it.start, mo->it.last); if (it) { struct drm_i915_gem_object *obj; @@ -312,86 +234,122 @@ i915_mmu_notifier_add(struct i915_mmu_notifier *mmu, obj = container_of(it, struct i915_mmu_object, it)->obj; if (!obj->userptr.workers) - mmu->has_linear = mn->is_linear = true; + mn->has_linear = mo->is_linear = true; else ret = -EAGAIN; } else - interval_tree_insert(&mn->it, &mmu->objects); + interval_tree_insert(&mo->it, &mn->objects); if (ret == 0) { - list_add(&mn->link, &mmu->linear); - __i915_mmu_notifier_update_serial(mmu); + list_add(&mo->link, &mn->linear); + __i915_mmu_notifier_update_serial(mn); } - spin_unlock(&mmu->lock); - mutex_unlock(&mmu->dev->struct_mutex); + spin_unlock(&mn->lock); + mutex_unlock(&dev->struct_mutex); return ret; } +static bool i915_mmu_notifier_has_linear(struct i915_mmu_notifier *mn) +{ + struct i915_mmu_object *mo; + + list_for_each_entry(mo, &mn->linear, link) + if (mo->is_linear) + return true; + + return false; +} + +static void +i915_mmu_notifier_del(struct i915_mmu_notifier *mn, + struct i915_mmu_object *mo) +{ + spin_lock(&mn->lock); + list_del(&mo->link); + if (mo->is_linear) + mn->has_linear = i915_mmu_notifier_has_linear(mn); + else + interval_tree_remove(&mo->it, &mn->objects); + __i915_mmu_notifier_update_serial(mn); + spin_unlock(&mn->lock); +} + static void i915_gem_userptr_release__mmu_notifier(struct drm_i915_gem_object *obj) { - struct i915_mmu_object *mn; + struct i915_mmu_object *mo; - mn = obj->userptr.mn; - if (mn == NULL) + mo = obj->userptr.mmu_object; + if (mo == NULL) return; - i915_mmu_notifier_del(mn->mmu, mn); - obj->userptr.mn = NULL; + i915_mmu_notifier_del(mo->mn, mo); + kfree(mo); + + obj->userptr.mmu_object = NULL; +} + +static struct i915_mmu_notifier * +i915_mmu_notifier_find(struct i915_mm_struct *mm) +{ + if (mm->mn == NULL) { + down_write(&mm->mm->mmap_sem); + mutex_lock(&to_i915(mm->dev)->mm_lock); + if (mm->mn == NULL) + mm->mn = i915_mmu_notifier_create(mm->mm); + mutex_unlock(&to_i915(mm->dev)->mm_lock); + up_write(&mm->mm->mmap_sem); + } + return mm->mn; } static int i915_gem_userptr_init__mmu_notifier(struct drm_i915_gem_object *obj, unsigned flags) { - struct i915_mmu_notifier *mmu; - struct i915_mmu_object *mn; + struct i915_mmu_notifier *mn; + struct i915_mmu_object *mo; int ret; if (flags & I915_USERPTR_UNSYNCHRONIZED) return capable(CAP_SYS_ADMIN) ? 0 : -EPERM; - down_write(&obj->userptr.mm->mmap_sem); - ret = i915_mutex_lock_interruptible(obj->base.dev); - if (ret == 0) { - mmu = i915_mmu_notifier_get(obj->base.dev, obj->userptr.mm); - if (!IS_ERR(mmu)) - mmu->count++; /* preemptive add to act as a refcount */ - else - ret = PTR_ERR(mmu); - mutex_unlock(&obj->base.dev->struct_mutex); - } - up_write(&obj->userptr.mm->mmap_sem); - if (ret) - return ret; + if (WARN_ON(obj->userptr.mm == NULL)) + return -EINVAL; - mn = kzalloc(sizeof(*mn), GFP_KERNEL); - if (mn == NULL) { - ret = -ENOMEM; - goto destroy_mmu; - } + mn = i915_mmu_notifier_find(obj->userptr.mm); + if (IS_ERR(mn)) + return PTR_ERR(mn); - mn->mmu = mmu; - mn->it.start = obj->userptr.ptr; - mn->it.last = mn->it.start + obj->base.size - 1; - mn->obj = obj; + mo = kzalloc(sizeof(*mo), GFP_KERNEL); + if (mo == NULL) + return -ENOMEM; - ret = i915_mmu_notifier_add(mmu, mn); - if (ret) - goto free_mn; + mo->mn = mn; + mo->it.start = obj->userptr.ptr; + mo->it.last = mo->it.start + obj->base.size - 1; + mo->obj = obj; - obj->userptr.mn = mn; + ret = i915_mmu_notifier_add(obj->base.dev, mn, mo); + if (ret) { + kfree(mo); + return ret; + } + + obj->userptr.mmu_object = mo; return 0; +} + +static void +i915_mmu_notifier_free(struct i915_mmu_notifier *mn, + struct mm_struct *mm) +{ + if (mn == NULL) + return; -free_mn: + mmu_notifier_unregister(&mn->mn, mm); kfree(mn); -destroy_mmu: - mutex_lock(&obj->base.dev->struct_mutex); - if (--mmu->count == 0) - __i915_mmu_notifier_destroy(mmu); - mutex_unlock(&obj->base.dev->struct_mutex); - return ret; } #else @@ -413,15 +371,114 @@ i915_gem_userptr_init__mmu_notifier(struct drm_i915_gem_object *obj, return 0; } + +static void +i915_mmu_notifier_free(struct i915_mmu_notifier *mn, + struct mm_struct *mm) +{ +} + #endif +static struct i915_mm_struct * +__i915_mm_struct_find(struct drm_i915_private *dev_priv, struct mm_struct *real) +{ + struct i915_mm_struct *mm; + + /* Protected by dev_priv->mm_lock */ + hash_for_each_possible(dev_priv->mm_structs, mm, node, (unsigned long)real) + if (mm->mm == real) + return mm; + + return NULL; +} + +static int +i915_gem_userptr_init__mm_struct(struct drm_i915_gem_object *obj) +{ + struct drm_i915_private *dev_priv = to_i915(obj->base.dev); + struct i915_mm_struct *mm; + int ret = 0; + + /* During release of the GEM object we hold the struct_mutex. This + * precludes us from calling mmput() at that time as that may be + * the last reference and so call exit_mmap(). exit_mmap() will + * attempt to reap the vma, and if we were holding a GTT mmap + * would then call drm_gem_vm_close() and attempt to reacquire + * the struct mutex. So in order to avoid that recursion, we have + * to defer releasing the mm reference until after we drop the + * struct_mutex, i.e. we need to schedule a worker to do the clean + * up. + */ + mutex_lock(&dev_priv->mm_lock); + mm = __i915_mm_struct_find(dev_priv, current->mm); + if (mm == NULL) { + mm = kmalloc(sizeof(*mm), GFP_KERNEL); + if (mm == NULL) { + ret = -ENOMEM; + goto out; + } + + kref_init(&mm->kref); + mm->dev = obj->base.dev; + + mm->mm = current->mm; + atomic_inc(¤t->mm->mm_count); + + mm->mn = NULL; + + /* Protected by dev_priv->mm_lock */ + hash_add(dev_priv->mm_structs, + &mm->node, (unsigned long)mm->mm); + } else + kref_get(&mm->kref); + + obj->userptr.mm = mm; +out: + mutex_unlock(&dev_priv->mm_lock); + return ret; +} + +static void +__i915_mm_struct_free__worker(struct work_struct *work) +{ + struct i915_mm_struct *mm = container_of(work, typeof(*mm), work); + i915_mmu_notifier_free(mm->mn, mm->mm); + mmdrop(mm->mm); + kfree(mm); +} + +static void +__i915_mm_struct_free(struct kref *kref) +{ + struct i915_mm_struct *mm = container_of(kref, typeof(*mm), kref); + + /* Protected by dev_priv->mm_lock */ + hash_del(&mm->node); + mutex_unlock(&to_i915(mm->dev)->mm_lock); + + INIT_WORK(&mm->work, __i915_mm_struct_free__worker); + schedule_work(&mm->work); +} + +static void +i915_gem_userptr_release__mm_struct(struct drm_i915_gem_object *obj) +{ + if (obj->userptr.mm == NULL) + return; + + kref_put_mutex(&obj->userptr.mm->kref, + __i915_mm_struct_free, + &to_i915(obj->base.dev)->mm_lock); + obj->userptr.mm = NULL; +} + struct get_pages_work { struct work_struct work; struct drm_i915_gem_object *obj; struct task_struct *task; }; - #if IS_ENABLED(CONFIG_SWIOTLB) #define swiotlb_active() swiotlb_nr_tbl() #else @@ -479,7 +536,7 @@ __i915_gem_userptr_get_pages_worker(struct work_struct *_work) if (pvec == NULL) pvec = drm_malloc_ab(num_pages, sizeof(struct page *)); if (pvec != NULL) { - struct mm_struct *mm = obj->userptr.mm; + struct mm_struct *mm = obj->userptr.mm->mm; down_read(&mm->mmap_sem); while (pinned < num_pages) { @@ -545,7 +602,7 @@ i915_gem_userptr_get_pages(struct drm_i915_gem_object *obj) pvec = NULL; pinned = 0; - if (obj->userptr.mm == current->mm) { + if (obj->userptr.mm->mm == current->mm) { pvec = kmalloc(num_pages*sizeof(struct page *), GFP_TEMPORARY | __GFP_NOWARN | __GFP_NORETRY); if (pvec == NULL) { @@ -651,17 +708,13 @@ static void i915_gem_userptr_release(struct drm_i915_gem_object *obj) { i915_gem_userptr_release__mmu_notifier(obj); - - if (obj->userptr.mm) { - mmput(obj->userptr.mm); - obj->userptr.mm = NULL; - } + i915_gem_userptr_release__mm_struct(obj); } static int i915_gem_userptr_dmabuf_export(struct drm_i915_gem_object *obj) { - if (obj->userptr.mn) + if (obj->userptr.mmu_object) return 0; return i915_gem_userptr_init__mmu_notifier(obj, 0); @@ -736,7 +789,6 @@ i915_gem_userptr_ioctl(struct drm_device *dev, void *data, struct drm_file *file return -ENODEV; } - /* Allocate the new object */ obj = i915_gem_object_alloc(dev); if (obj == NULL) return -ENOMEM; @@ -754,8 +806,8 @@ i915_gem_userptr_ioctl(struct drm_device *dev, void *data, struct drm_file *file * at binding. This means that we need to hook into the mmu_notifier * in order to detect if the mmu is destroyed. */ - ret = -ENOMEM; - if ((obj->userptr.mm = get_task_mm(current))) + ret = i915_gem_userptr_init__mm_struct(obj); + if (ret == 0) ret = i915_gem_userptr_init__mmu_notifier(obj, args->flags); if (ret == 0) ret = drm_gem_handle_create(file, &obj->base, &handle); @@ -772,9 +824,8 @@ i915_gem_userptr_ioctl(struct drm_device *dev, void *data, struct drm_file *file int i915_gem_init_userptr(struct drm_device *dev) { -#if defined(CONFIG_MMU_NOTIFIER) struct drm_i915_private *dev_priv = to_i915(dev); - hash_init(dev_priv->mmu_notifiers); -#endif + mutex_init(&dev_priv->mm_lock); + hash_init(dev_priv->mm_structs); return 0; } |