drm/i915: Move more GEM objects under gem/

Continuing the theme of separating out the GEM clutter.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190528092956.14910-8-chris@chris-wilson.co.uk

1 files changed, 0 insertions, 851 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem_userptr.c b/drivers/gpu/drm/i915/i915_gem_userptr.c
deleted file mode 100644
index 2c1b6bb7a040..000000000000
--- a/drivers/gpu/drm/i915/i915_gem_userptr.c
+++ /dev/null
@@ -1,851 +0,0 @@
-/*
- * Copyright © 2012-2014 Intel Corporation
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the "Software"),
- * to deal in the Software without restriction, including without limitation
- * the rights to use, copy, modify, merge, publish, distribute, sublicense,
- * and/or sell copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice (including the next
- * paragraph) shall be included in all copies or substantial portions of the
- * Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
- * IN THE SOFTWARE.
- *
- */
-
-#include <linux/mmu_context.h>
-#include <linux/mmu_notifier.h>
-#include <linux/mempolicy.h>
-#include <linux/swap.h>
-#include <linux/sched/mm.h>
-
-#include <drm/i915_drm.h>
-
-#include "gem/i915_gem_ioctls.h"
-
-#include "i915_drv.h"
-#include "i915_trace.h"
-#include "intel_drv.h"
-
-struct i915_mm_struct {
-	struct mm_struct *mm;
-	struct drm_i915_private *i915;
-	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 i915_mmu_notifier {
-	spinlock_t lock;
-	struct hlist_node node;
-	struct mmu_notifier mn;
-	struct rb_root_cached objects;
-	struct i915_mm_struct *mm;
-};
-
-struct i915_mmu_object {
-	struct i915_mmu_notifier *mn;
-	struct drm_i915_gem_object *obj;
-	struct interval_tree_node it;
-};
-
-static void add_object(struct i915_mmu_object *mo)
-{
-	GEM_BUG_ON(!RB_EMPTY_NODE(&mo->it.rb));
-	interval_tree_insert(&mo->it, &mo->mn->objects);
-}
-
-static void del_object(struct i915_mmu_object *mo)
-{
-	if (RB_EMPTY_NODE(&mo->it.rb))
-		return;
-
-	interval_tree_remove(&mo->it, &mo->mn->objects);
-	RB_CLEAR_NODE(&mo->it.rb);
-}
-
-static void
-__i915_gem_userptr_set_active(struct drm_i915_gem_object *obj, bool value)
-{
-	struct i915_mmu_object *mo = obj->userptr.mmu_object;
-
-	/*
-	 * During mm_invalidate_range we need to cancel any userptr that
-	 * overlaps the range being invalidated. Doing so requires the
-	 * struct_mutex, and that risks recursion. In order to cause
-	 * recursion, the user must alias the userptr address space with
-	 * a GTT mmapping (possible with a MAP_FIXED) - then when we have
-	 * to invalidate that mmaping, mm_invalidate_range is called with
-	 * the userptr address *and* the struct_mutex held.  To prevent that
-	 * we set a flag under the i915_mmu_notifier spinlock to indicate
-	 * whether this object is valid.
-	 */
-	if (!mo)
-		return;
-
-	spin_lock(&mo->mn->lock);
-	if (value)
-		add_object(mo);
-	else
-		del_object(mo);
-	spin_unlock(&mo->mn->lock);
-}
-
-static int
-userptr_mn_invalidate_range_start(struct mmu_notifier *_mn,
-				  const struct mmu_notifier_range *range)
-{
-	struct i915_mmu_notifier *mn =
-		container_of(_mn, struct i915_mmu_notifier, mn);
-	struct interval_tree_node *it;
-	struct mutex *unlock = NULL;
-	unsigned long end;
-	int ret = 0;
-
-	if (RB_EMPTY_ROOT(&mn->objects.rb_root))
-		return 0;
-
-	/* interval ranges are inclusive, but invalidate range is exclusive */
-	end = range->end - 1;
-
-	spin_lock(&mn->lock);
-	it = interval_tree_iter_first(&mn->objects, range->start, end);
-	while (it) {
-		struct drm_i915_gem_object *obj;
-
-		if (!mmu_notifier_range_blockable(range)) {
-			ret = -EAGAIN;
-			break;
-		}
-
-		/*
-		 * The mmu_object is released late when destroying the
-		 * GEM object so it is entirely possible to gain a
-		 * reference on an object in the process of being freed
-		 * since our serialisation is via the spinlock and not
-		 * the struct_mutex - and consequently use it after it
-		 * is freed and then double free it. To prevent that
-		 * use-after-free we only acquire a reference on the
-		 * object if it is not in the process of being destroyed.
-		 */
-		obj = container_of(it, struct i915_mmu_object, it)->obj;
-		if (!kref_get_unless_zero(&obj->base.refcount)) {
-			it = interval_tree_iter_next(it, range->start, end);
-			continue;
-		}
-		spin_unlock(&mn->lock);
-
-		if (!unlock) {
-			unlock = &mn->mm->i915->drm.struct_mutex;
-
-			switch (mutex_trylock_recursive(unlock)) {
-			default:
-			case MUTEX_TRYLOCK_FAILED:
-				if (mutex_lock_killable_nested(unlock, I915_MM_SHRINKER)) {
-					i915_gem_object_put(obj);
-					return -EINTR;
-				}
-				/* fall through */
-			case MUTEX_TRYLOCK_SUCCESS:
-				break;
-
-			case MUTEX_TRYLOCK_RECURSIVE:
-				unlock = ERR_PTR(-EEXIST);
-				break;
-			}
-		}
-
-		ret = i915_gem_object_unbind(obj);
-		if (ret == 0)
-			ret = __i915_gem_object_put_pages(obj, I915_MM_SHRINKER);
-		i915_gem_object_put(obj);
-		if (ret)
-			goto unlock;
-
-		spin_lock(&mn->lock);
-
-		/*
-		 * As we do not (yet) protect the mmu from concurrent insertion
-		 * over this range, there is no guarantee that this search will
-		 * terminate given a pathologic workload.
-		 */
-		it = interval_tree_iter_first(&mn->objects, range->start, end);
-	}
-	spin_unlock(&mn->lock);
-
-unlock:
-	if (!IS_ERR_OR_NULL(unlock))
-		mutex_unlock(unlock);
-
-	return ret;
-
-}
-
-static const struct mmu_notifier_ops i915_gem_userptr_notifier = {
-	.invalidate_range_start = userptr_mn_invalidate_range_start,
-};
-
-static struct i915_mmu_notifier *
-i915_mmu_notifier_create(struct i915_mm_struct *mm)
-{
-	struct i915_mmu_notifier *mn;
-
-	mn = kmalloc(sizeof(*mn), GFP_KERNEL);
-	if (mn == NULL)
-		return ERR_PTR(-ENOMEM);
-
-	spin_lock_init(&mn->lock);
-	mn->mn.ops = &i915_gem_userptr_notifier;
-	mn->objects = RB_ROOT_CACHED;
-	mn->mm = mm;
-
-	return mn;
-}
-
-static void
-i915_gem_userptr_release__mmu_notifier(struct drm_i915_gem_object *obj)
-{
-	struct i915_mmu_object *mo;
-
-	mo = fetch_and_zero(&obj->userptr.mmu_object);
-	if (!mo)
-		return;
-
-	spin_lock(&mo->mn->lock);
-	del_object(mo);
-	spin_unlock(&mo->mn->lock);
-	kfree(mo);
-}
-
-static struct i915_mmu_notifier *
-i915_mmu_notifier_find(struct i915_mm_struct *mm)
-{
-	struct i915_mmu_notifier *mn;
-	int err = 0;
-
-	mn = mm->mn;
-	if (mn)
-		return mn;
-
-	mn = i915_mmu_notifier_create(mm);
-	if (IS_ERR(mn))
-		err = PTR_ERR(mn);
-
-	down_write(&mm->mm->mmap_sem);
-	mutex_lock(&mm->i915->mm_lock);
-	if (mm->mn == NULL && !err) {
-		/* Protected by mmap_sem (write-lock) */
-		err = __mmu_notifier_register(&mn->mn, mm->mm);
-		if (!err) {
-			/* Protected by mm_lock */
-			mm->mn = fetch_and_zero(&mn);
-		}
-	} else if (mm->mn) {
-		/*
-		 * Someone else raced and successfully installed the mmu
-		 * notifier, we can cancel our own errors.
-		 */
-		err = 0;
-	}
-	mutex_unlock(&mm->i915->mm_lock);
-	up_write(&mm->mm->mmap_sem);
-
-	if (mn && !IS_ERR(mn))
-		kfree(mn);
-
-	return err ? ERR_PTR(err) : mm->mn;
-}
-
-static int
-i915_gem_userptr_init__mmu_notifier(struct drm_i915_gem_object *obj,
-				    unsigned flags)
-{
-	struct i915_mmu_notifier *mn;
-	struct i915_mmu_object *mo;
-
-	if (flags & I915_USERPTR_UNSYNCHRONIZED)
-		return capable(CAP_SYS_ADMIN) ? 0 : -EPERM;
-
-	if (WARN_ON(obj->userptr.mm == NULL))
-		return -EINVAL;
-
-	mn = i915_mmu_notifier_find(obj->userptr.mm);
-	if (IS_ERR(mn))
-		return PTR_ERR(mn);
-
-	mo = kzalloc(sizeof(*mo), GFP_KERNEL);
-	if (!mo)
-		return -ENOMEM;
-
-	mo->mn = mn;
-	mo->obj = obj;
-	mo->it.start = obj->userptr.ptr;
-	mo->it.last = obj->userptr.ptr + obj->base.size - 1;
-	RB_CLEAR_NODE(&mo->it.rb);
-
-	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;
-
-	mmu_notifier_unregister(&mn->mn, mm);
-	kfree(mn);
-}
-
-#else
-
-static void
-__i915_gem_userptr_set_active(struct drm_i915_gem_object *obj, bool value)
-{
-}
-
-static void
-i915_gem_userptr_release__mmu_notifier(struct drm_i915_gem_object *obj)
-{
-}
-
-static int
-i915_gem_userptr_init__mmu_notifier(struct drm_i915_gem_object *obj,
-				    unsigned flags)
-{
-	if ((flags & I915_USERPTR_UNSYNCHRONIZED) == 0)
-		return -ENODEV;
-
-	if (!capable(CAP_SYS_ADMIN))
-		return -EPERM;
-
-	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->i915 = to_i915(obj->base.dev);
-
-		mm->mm = current->mm;
-		mmgrab(current->mm);
-
-		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(&mm->i915->mm_lock);
-
-	INIT_WORK(&mm->work, __i915_mm_struct_free__worker);
-	queue_work(mm->i915->mm.userptr_wq, &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;
-};
-
-static struct sg_table *
-__i915_gem_userptr_alloc_pages(struct drm_i915_gem_object *obj,
-			       struct page **pvec, int num_pages)
-{
-	unsigned int max_segment = i915_sg_segment_size();
-	struct sg_table *st;
-	unsigned int sg_page_sizes;
-	int ret;
-
-	st = kmalloc(sizeof(*st), GFP_KERNEL);
-	if (!st)
-		return ERR_PTR(-ENOMEM);
-
-alloc_table:
-	ret = __sg_alloc_table_from_pages(st, pvec, num_pages,
-					  0, num_pages << PAGE_SHIFT,
-					  max_segment,
-					  GFP_KERNEL);
-	if (ret) {
-		kfree(st);
-		return ERR_PTR(ret);
-	}
-
-	ret = i915_gem_gtt_prepare_pages(obj, st);
-	if (ret) {
-		sg_free_table(st);
-
-		if (max_segment > PAGE_SIZE) {
-			max_segment = PAGE_SIZE;
-			goto alloc_table;
-		}
-
-		kfree(st);
-		return ERR_PTR(ret);
-	}
-
-	sg_page_sizes = i915_sg_page_sizes(st->sgl);
-
-	__i915_gem_object_set_pages(obj, st, sg_page_sizes);
-
-	return st;
-}
-
-static void
-__i915_gem_userptr_get_pages_worker(struct work_struct *_work)
-{
-	struct get_pages_work *work = container_of(_work, typeof(*work), work);
-	struct drm_i915_gem_object *obj = work->obj;
-	const int npages = obj->base.size >> PAGE_SHIFT;
-	struct page **pvec;
-	int pinned, ret;
-
-	ret = -ENOMEM;
-	pinned = 0;
-
-	pvec = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
-	if (pvec != NULL) {
-		struct mm_struct *mm = obj->userptr.mm->mm;
-		unsigned int flags = 0;
-
-		if (!i915_gem_object_is_readonly(obj))
-			flags |= FOLL_WRITE;
-
-		ret = -EFAULT;
-		if (mmget_not_zero(mm)) {
-			down_read(&mm->mmap_sem);
-			while (pinned < npages) {
-				ret = get_user_pages_remote
-					(work->task, mm,
-					 obj->userptr.ptr + pinned * PAGE_SIZE,
-					 npages - pinned,
-					 flags,
-					 pvec + pinned, NULL, NULL);
-				if (ret < 0)
-					break;
-
-				pinned += ret;
-			}
-			up_read(&mm->mmap_sem);
-			mmput(mm);
-		}
-	}
-
-	mutex_lock(&obj->mm.lock);
-	if (obj->userptr.work == &work->work) {
-		struct sg_table *pages = ERR_PTR(ret);
-
-		if (pinned == npages) {
-			pages = __i915_gem_userptr_alloc_pages(obj, pvec,
-							       npages);
-			if (!IS_ERR(pages)) {
-				pinned = 0;
-				pages = NULL;
-			}
-		}
-
-		obj->userptr.work = ERR_CAST(pages);
-		if (IS_ERR(pages))
-			__i915_gem_userptr_set_active(obj, false);
-	}
-	mutex_unlock(&obj->mm.lock);
-
-	release_pages(pvec, pinned);
-	kvfree(pvec);
-
-	i915_gem_object_put(obj);
-	put_task_struct(work->task);
-	kfree(work);
-}
-
-static struct sg_table *
-__i915_gem_userptr_get_pages_schedule(struct drm_i915_gem_object *obj)
-{
-	struct get_pages_work *work;
-
-	/* Spawn a worker so that we can acquire the
-	 * user pages without holding our mutex. Access
-	 * to the user pages requires mmap_sem, and we have
-	 * a strict lock ordering of mmap_sem, struct_mutex -
-	 * we already hold struct_mutex here and so cannot
-	 * call gup without encountering a lock inversion.
-	 *
-	 * Userspace will keep on repeating the operation
-	 * (thanks to EAGAIN) until either we hit the fast
-	 * path or the worker completes. If the worker is
-	 * cancelled or superseded, the task is still run
-	 * but the results ignored. (This leads to
-	 * complications that we may have a stray object
-	 * refcount that we need to be wary of when
-	 * checking for existing objects during creation.)
-	 * If the worker encounters an error, it reports
-	 * that error back to this function through
-	 * obj->userptr.work = ERR_PTR.
-	 */
-	work = kmalloc(sizeof(*work), GFP_KERNEL);
-	if (work == NULL)
-		return ERR_PTR(-ENOMEM);
-
-	obj->userptr.work = &work->work;
-
-	work->obj = i915_gem_object_get(obj);
-
-	work->task = current;
-	get_task_struct(work->task);
-
-	INIT_WORK(&work->work, __i915_gem_userptr_get_pages_worker);
-	queue_work(to_i915(obj->base.dev)->mm.userptr_wq, &work->work);
-
-	return ERR_PTR(-EAGAIN);
-}
-
-static int i915_gem_userptr_get_pages(struct drm_i915_gem_object *obj)
-{
-	const int num_pages = obj->base.size >> PAGE_SHIFT;
-	struct mm_struct *mm = obj->userptr.mm->mm;
-	struct page **pvec;
-	struct sg_table *pages;
-	bool active;
-	int pinned;
-
-	/* If userspace should engineer that these pages are replaced in
-	 * the vma between us binding this page into the GTT and completion
-	 * of rendering... Their loss. If they change the mapping of their
-	 * pages they need to create a new bo to point to the new vma.
-	 *
-	 * However, that still leaves open the possibility of the vma
-	 * being copied upon fork. Which falls under the same userspace
-	 * synchronisation issue as a regular bo, except that this time
-	 * the process may not be expecting that a particular piece of
-	 * memory is tied to the GPU.
-	 *
-	 * Fortunately, we can hook into the mmu_notifier in order to
-	 * discard the page references prior to anything nasty happening
-	 * to the vma (discard or cloning) which should prevent the more
-	 * egregious cases from causing harm.
-	 */
-
-	if (obj->userptr.work) {
-		/* active flag should still be held for the pending work */
-		if (IS_ERR(obj->userptr.work))
-			return PTR_ERR(obj->userptr.work);
-		else
-			return -EAGAIN;
-	}
-
-	pvec = NULL;
-	pinned = 0;
-
-	if (mm == current->mm) {
-		pvec = kvmalloc_array(num_pages, sizeof(struct page *),
-				      GFP_KERNEL |
-				      __GFP_NORETRY |
-				      __GFP_NOWARN);
-		if (pvec) /* defer to worker if malloc fails */
-			pinned = __get_user_pages_fast(obj->userptr.ptr,
-						       num_pages,
-						       !i915_gem_object_is_readonly(obj),
-						       pvec);
-	}
-
-	active = false;
-	if (pinned < 0) {
-		pages = ERR_PTR(pinned);
-		pinned = 0;
-	} else if (pinned < num_pages) {
-		pages = __i915_gem_userptr_get_pages_schedule(obj);
-		active = pages == ERR_PTR(-EAGAIN);
-	} else {
-		pages = __i915_gem_userptr_alloc_pages(obj, pvec, num_pages);
-		active = !IS_ERR(pages);
-	}
-	if (active)
-		__i915_gem_userptr_set_active(obj, true);
-
-	if (IS_ERR(pages))
-		release_pages(pvec, pinned);
-	kvfree(pvec);
-
-	return PTR_ERR_OR_ZERO(pages);
-}
-
-static void
-i915_gem_userptr_put_pages(struct drm_i915_gem_object *obj,
-			   struct sg_table *pages)
-{
-	struct sgt_iter sgt_iter;
-	struct page *page;
-
-	/* Cancel any inflight work and force them to restart their gup */
-	obj->userptr.work = NULL;
-	__i915_gem_userptr_set_active(obj, false);
-	if (!pages)
-		return;
-
-	__i915_gem_object_release_shmem(obj, pages, true);
-	i915_gem_gtt_finish_pages(obj, pages);
-
-	for_each_sgt_page(page, sgt_iter, pages) {
-		if (obj->mm.dirty)
-			set_page_dirty(page);
-
-		mark_page_accessed(page);
-		put_page(page);
-	}
-	obj->mm.dirty = false;
-
-	sg_free_table(pages);
-	kfree(pages);
-}
-
-static void
-i915_gem_userptr_release(struct drm_i915_gem_object *obj)
-{
-	i915_gem_userptr_release__mmu_notifier(obj);
-	i915_gem_userptr_release__mm_struct(obj);
-}
-
-static int
-i915_gem_userptr_dmabuf_export(struct drm_i915_gem_object *obj)
-{
-	if (obj->userptr.mmu_object)
-		return 0;
-
-	return i915_gem_userptr_init__mmu_notifier(obj, 0);
-}
-
-static const struct drm_i915_gem_object_ops i915_gem_userptr_ops = {
-	.flags = I915_GEM_OBJECT_HAS_STRUCT_PAGE |
-		 I915_GEM_OBJECT_IS_SHRINKABLE |
-		 I915_GEM_OBJECT_ASYNC_CANCEL,
-	.get_pages = i915_gem_userptr_get_pages,
-	.put_pages = i915_gem_userptr_put_pages,
-	.dmabuf_export = i915_gem_userptr_dmabuf_export,
-	.release = i915_gem_userptr_release,
-};
-
-/*
- * Creates a new mm object that wraps some normal memory from the process
- * context - user memory.
- *
- * We impose several restrictions upon the memory being mapped
- * into the GPU.
- * 1. It must be page aligned (both start/end addresses, i.e ptr and size).
- * 2. It must be normal system memory, not a pointer into another map of IO
- *    space (e.g. it must not be a GTT mmapping of another object).
- * 3. We only allow a bo as large as we could in theory map into the GTT,
- *    that is we limit the size to the total size of the GTT.
- * 4. The bo is marked as being snoopable. The backing pages are left
- *    accessible directly by the CPU, but reads and writes by the GPU may
- *    incur the cost of a snoop (unless you have an LLC architecture).
- *
- * Synchronisation between multiple users and the GPU is left to userspace
- * through the normal set-domain-ioctl. The kernel will enforce that the
- * GPU relinquishes the VMA before it is returned back to the system
- * i.e. upon free(), munmap() or process termination. However, the userspace
- * malloc() library may not immediately relinquish the VMA after free() and
- * instead reuse it whilst the GPU is still reading and writing to the VMA.
- * Caveat emptor.
- *
- * Also note, that the object created here is not currently a "first class"
- * object, in that several ioctls are banned. These are the CPU access
- * ioctls: mmap(), pwrite and pread. In practice, you are expected to use
- * direct access via your pointer rather than use those ioctls. Another
- * restriction is that we do not allow userptr surfaces to be pinned to the
- * hardware and so we reject any attempt to create a framebuffer out of a
- * userptr.
- *
- * If you think this is a good interface to use to pass GPU memory between
- * drivers, please use dma-buf instead. In fact, wherever possible use
- * dma-buf instead.
- */
-int
-i915_gem_userptr_ioctl(struct drm_device *dev,
-		       void *data,
-		       struct drm_file *file)
-{
-	struct drm_i915_private *dev_priv = to_i915(dev);
-	struct drm_i915_gem_userptr *args = data;
-	struct drm_i915_gem_object *obj;
-	int ret;
-	u32 handle;
-
-	if (!HAS_LLC(dev_priv) && !HAS_SNOOP(dev_priv)) {
-		/* We cannot support coherent userptr objects on hw without
-		 * LLC and broken snooping.
-		 */
-		return -ENODEV;
-	}
-
-	if (args->flags & ~(I915_USERPTR_READ_ONLY |
-			    I915_USERPTR_UNSYNCHRONIZED))
-		return -EINVAL;
-
-	if (!args->user_size)
-		return -EINVAL;
-
-	if (offset_in_page(args->user_ptr | args->user_size))
-		return -EINVAL;
-
-	if (!access_ok((char __user *)(unsigned long)args->user_ptr, args->user_size))
-		return -EFAULT;
-
-	if (args->flags & I915_USERPTR_READ_ONLY) {
-		struct i915_hw_ppgtt *ppgtt;
-
-		/*
-		 * On almost all of the older hw, we cannot tell the GPU that
-		 * a page is readonly.
-		 */
-		ppgtt = dev_priv->kernel_context->ppgtt;
-		if (!ppgtt || !ppgtt->vm.has_read_only)
-			return -ENODEV;
-	}
-
-	obj = i915_gem_object_alloc();
-	if (obj == NULL)
-		return -ENOMEM;
-
-	drm_gem_private_object_init(dev, &obj->base, args->user_size);
-	i915_gem_object_init(obj, &i915_gem_userptr_ops);
-	obj->read_domains = I915_GEM_DOMAIN_CPU;
-	obj->write_domain = I915_GEM_DOMAIN_CPU;
-	i915_gem_object_set_cache_coherency(obj, I915_CACHE_LLC);
-
-	obj->userptr.ptr = args->user_ptr;
-	if (args->flags & I915_USERPTR_READ_ONLY)
-		i915_gem_object_set_readonly(obj);
-
-	/* And keep a pointer to the current->mm for resolving the user pages
-	 * at binding. This means that we need to hook into the mmu_notifier
-	 * in order to detect if the mmu is destroyed.
-	 */
-	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);
-
-	/* drop reference from allocate - handle holds it now */
-	i915_gem_object_put(obj);
-	if (ret)
-		return ret;
-
-	args->handle = handle;
-	return 0;
-}
-
-int i915_gem_init_userptr(struct drm_i915_private *dev_priv)
-{
-	mutex_init(&dev_priv->mm_lock);
-	hash_init(dev_priv->mm_structs);
-
-	dev_priv->mm.userptr_wq =
-		alloc_workqueue("i915-userptr-acquire",
-				WQ_HIGHPRI | WQ_UNBOUND,
-				0);
-	if (!dev_priv->mm.userptr_wq)
-		return -ENOMEM;
-
-	return 0;
-}
-
-void i915_gem_cleanup_userptr(struct drm_i915_private *dev_priv)
-{
-	destroy_workqueue(dev_priv->mm.userptr_wq);
-}