diff options
| -rw-r--r-- | drivers/gpu/drm/i915/i915_gem_userptr.c | 88 |
1 files changed, 62 insertions, 26 deletions
diff --git a/drivers/gpu/drm/i915/i915_gem_userptr.c b/drivers/gpu/drm/i915/i915_gem_userptr.c index dc9bf5282071..07046fa4c6a9 100644 --- a/drivers/gpu/drm/i915/i915_gem_userptr.c +++ b/drivers/gpu/drm/i915/i915_gem_userptr.c @@ -488,6 +488,37 @@ __i915_gem_userptr_set_active(struct drm_i915_gem_object *obj, return ret; } +static bool noncontiguous_or_overlaps_ggtt(struct drm_i915_gem_object *obj, + struct mm_struct *mm) +{ + const struct vm_operations_struct *gem_vm_ops = + obj->base.dev->driver->gem_vm_ops; + unsigned long addr = obj->userptr.ptr; + const unsigned long end = addr + obj->base.size; + struct vm_area_struct *vma; + + /* Check for a contiguous set of vma covering the userptr, if any + * are absent, they will EFAULT. More importantly if any point back + * to a drm_i915_gem_object GTT mmaping, we may trigger a deadlock + * between the deferred gup of this userptr and the object being + * unbound calling invalidate_range -> cancel_userptr. + */ + for (vma = find_vma(mm, addr); vma; vma = vma->vm_next) { + if (vma->vm_start > addr) /* gap */ + break; + + if (vma->vm_ops == gem_vm_ops) /* GTT mmapping */ + break; + + if (vma->vm_end >= end) + return false; + + addr = vma->vm_end; + } + + return true; +} + static void __i915_gem_userptr_get_pages_worker(struct work_struct *_work) { @@ -556,8 +587,7 @@ __i915_gem_userptr_get_pages_worker(struct work_struct *_work) } static struct sg_table * -__i915_gem_userptr_get_pages_schedule(struct drm_i915_gem_object *obj, - bool *active) +__i915_gem_userptr_get_pages_schedule(struct drm_i915_gem_object *obj) { struct get_pages_work *work; @@ -594,7 +624,6 @@ __i915_gem_userptr_get_pages_schedule(struct drm_i915_gem_object *obj, INIT_WORK(&work->work, __i915_gem_userptr_get_pages_worker); schedule_work(&work->work); - *active = true; return ERR_PTR(-EAGAIN); } @@ -602,10 +631,11 @@ static struct sg_table * 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; - int pinned, ret; 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 @@ -632,37 +662,43 @@ i915_gem_userptr_get_pages(struct drm_i915_gem_object *obj) return ERR_PTR(-EAGAIN); } - /* Let the mmu-notifier know that we have begun and need cancellation */ - ret = __i915_gem_userptr_set_active(obj, true); - if (ret) - return ERR_PTR(ret); - pvec = NULL; pinned = 0; - if (obj->userptr.mm->mm == current->mm) { - pvec = drm_malloc_gfp(num_pages, sizeof(struct page *), - GFP_TEMPORARY); - if (pvec == NULL) { - __i915_gem_userptr_set_active(obj, false); - return ERR_PTR(-ENOMEM); - } - pinned = __get_user_pages_fast(obj->userptr.ptr, num_pages, - !obj->userptr.read_only, pvec); + down_read(&mm->mmap_sem); + if (unlikely(noncontiguous_or_overlaps_ggtt(obj, mm))) { + pinned = -EFAULT; + } else if (mm == current->mm) { + pvec = drm_malloc_gfp(num_pages, sizeof(struct page *), + GFP_TEMPORARY | + __GFP_NORETRY | + __GFP_NOWARN); + if (pvec) /* defer to worker if malloc fails */ + pinned = __get_user_pages_fast(obj->userptr.ptr, + num_pages, + !obj->userptr.read_only, + 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); - else + 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_set_pages(obj, pvec, num_pages); - if (IS_ERR(pages)) { - __i915_gem_userptr_set_active(obj, active); - release_pages(pvec, pinned, 0); + active = !IS_ERR(pages); } + if (active) + __i915_gem_userptr_set_active(obj, true); + up_read(&mm->mmap_sem); + + if (IS_ERR(pages)) + release_pages(pvec, pinned, 0); drm_free_large(pvec); + return pages; } |