#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>
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;
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);
};
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;
* 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;
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
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
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) {
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) {
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);
return -ENODEV;
}
- /* Allocate the new object */
obj = i915_gem_object_alloc(dev);
if (obj == NULL)
return -ENOMEM;
* 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);
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;
}
projects / cascardo / linux.git / commitdiff