[deliverable/linux.git] / drivers / gpu / drm / ttm / ttm_bo_vm.c

/**************************************************************************
 *
 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
 * All Rights Reserved.
 *
 * 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, sub license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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.
 *
 **************************************************************************/
/*
 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
 */

#define pr_fmt(fmt) "[TTM] " fmt

#include <ttm/ttm_module.h>
#include <ttm/ttm_bo_driver.h>
#include <ttm/ttm_placement.h>
#include <drm/drm_vma_manager.h>
#include <linux/mm.h>
#include <linux/rbtree.h>
#include <linux/module.h>
#include <linux/uaccess.h>

#define TTM_BO_VM_NUM_PREFAULT 16

static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo,
				struct vm_area_struct *vma,
				struct vm_fault *vmf)
{
	struct ttm_bo_device *bdev = bo->bdev;
	int ret = 0;

	spin_lock(&bdev->fence_lock);
	if (likely(!test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)))
		goto out_unlock;

	/*
	 * Quick non-stalling check for idle.
	 */
	ret = ttm_bo_wait(bo, false, false, true);
	if (likely(ret == 0))
		goto out_unlock;

	/*
	 * If possible, avoid waiting for GPU with mmap_sem
	 * held.
	 */
	if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
		ret = VM_FAULT_RETRY;
		if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT)
			goto out_unlock;

		up_read(&vma->vm_mm->mmap_sem);
		(void) ttm_bo_wait(bo, false, true, false);
		goto out_unlock;
	}

	/*
	 * Ordinary wait.
	 */
	ret = ttm_bo_wait(bo, false, true, false);
	if (unlikely(ret != 0))
		ret = (ret != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
			VM_FAULT_NOPAGE;

out_unlock:
	spin_unlock(&bdev->fence_lock);
	return ret;
}

static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
{
	struct ttm_buffer_object *bo = (struct ttm_buffer_object *)
	    vma->vm_private_data;
	struct ttm_bo_device *bdev = bo->bdev;
	unsigned long page_offset;
	unsigned long page_last;
	unsigned long pfn;
	struct ttm_tt *ttm = NULL;
	struct page *page;
	int ret;
	int i;
	unsigned long address = (unsigned long)vmf->virtual_address;
	int retval = VM_FAULT_NOPAGE;
	struct ttm_mem_type_manager *man =
		&bdev->man[bo->mem.mem_type];
	struct vm_area_struct cvma;

	/*
	 * Work around locking order reversal in fault / nopfn
	 * between mmap_sem and bo_reserve: Perform a trylock operation
	 * for reserve, and if it fails, retry the fault after scheduling.
	 */

	ret = ttm_bo_reserve(bo, true, true, false, 0);
	if (unlikely(ret != 0)) {
		if (ret == -EBUSY)
			set_need_resched();
		return VM_FAULT_NOPAGE;
	}

	if (bdev->driver->fault_reserve_notify) {
		ret = bdev->driver->fault_reserve_notify(bo);
		switch (ret) {
		case 0:
			break;
		case -EBUSY:
			set_need_resched();
		case -ERESTARTSYS:
			retval = VM_FAULT_NOPAGE;
			goto out_unlock;
		default:
			retval = VM_FAULT_SIGBUS;
			goto out_unlock;
		}
	}

	/*
	 * Wait for buffer data in transit, due to a pipelined
	 * move.
	 */
	ret = ttm_bo_vm_fault_idle(bo, vma, vmf);
	if (unlikely(ret != 0)) {
		retval = ret;
		goto out_unlock;
	}

	ret = ttm_mem_io_lock(man, true);
	if (unlikely(ret != 0)) {
		retval = VM_FAULT_NOPAGE;
		goto out_unlock;
	}
	ret = ttm_mem_io_reserve_vm(bo);
	if (unlikely(ret != 0)) {
		retval = VM_FAULT_SIGBUS;
		goto out_io_unlock;
	}

	page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
	    drm_vma_node_start(&bo->vma_node) - vma->vm_pgoff;
	page_last = vma_pages(vma) +
	    drm_vma_node_start(&bo->vma_node) - vma->vm_pgoff;

	if (unlikely(page_offset >= bo->num_pages)) {
		retval = VM_FAULT_SIGBUS;
		goto out_io_unlock;
	}

	/*
	 * Make a local vma copy to modify the page_prot member
	 * and vm_flags if necessary. The vma parameter is protected
	 * by mmap_sem in write mode.
	 */
	cvma = *vma;
	cvma.vm_page_prot = vm_get_page_prot(cvma.vm_flags);

	if (bo->mem.bus.is_iomem) {
		cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
						cvma.vm_page_prot);
	} else {
		ttm = bo->ttm;
		if (!(bo->mem.placement & TTM_PL_FLAG_CACHED))
			cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
							cvma.vm_page_prot);

		/* Allocate all page at once, most common usage */
		if (ttm->bdev->driver->ttm_tt_populate(ttm)) {
			retval = VM_FAULT_OOM;
			goto out_io_unlock;
		}
	}

	/*
	 * Speculatively prefault a number of pages. Only error on
	 * first page.
	 */
	for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) {
		if (bo->mem.bus.is_iomem)
			pfn = ((bo->mem.bus.base + bo->mem.bus.offset) >> PAGE_SHIFT) + page_offset;
		else {
			page = ttm->pages[page_offset];
			if (unlikely(!page && i == 0)) {
				retval = VM_FAULT_OOM;
				goto out_io_unlock;
			} else if (unlikely(!page)) {
				break;
			}
			pfn = page_to_pfn(page);
		}

		ret = vm_insert_mixed(&cvma, address, pfn);
		/*
		 * Somebody beat us to this PTE or prefaulting to
		 * an already populated PTE, or prefaulting error.
		 */

		if (unlikely((ret == -EBUSY) || (ret != 0 && i > 0)))
			break;
		else if (unlikely(ret != 0)) {
			retval =
			    (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
			goto out_io_unlock;
		}

		address += PAGE_SIZE;
		if (unlikely(++page_offset >= page_last))
			break;
	}
out_io_unlock:
	ttm_mem_io_unlock(man);
out_unlock:
	ttm_bo_unreserve(bo);
	return retval;
}

static void ttm_bo_vm_open(struct vm_area_struct *vma)
{
	struct ttm_buffer_object *bo =
	    (struct ttm_buffer_object *)vma->vm_private_data;

	(void)ttm_bo_reference(bo);
}

static void ttm_bo_vm_close(struct vm_area_struct *vma)
{
	struct ttm_buffer_object *bo = (struct ttm_buffer_object *)vma->vm_private_data;

	ttm_bo_unref(&bo);
	vma->vm_private_data = NULL;
}

static const struct vm_operations_struct ttm_bo_vm_ops = {
	.fault = ttm_bo_vm_fault,
	.open = ttm_bo_vm_open,
	.close = ttm_bo_vm_close
};

static struct ttm_buffer_object *ttm_bo_vm_lookup(struct ttm_bo_device *bdev,
						  unsigned long offset,
						  unsigned long pages)
{
	struct drm_vma_offset_node *node;
	struct ttm_buffer_object *bo = NULL;

	drm_vma_offset_lock_lookup(&bdev->vma_manager);

	node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, pages);
	if (likely(node)) {
		bo = container_of(node, struct ttm_buffer_object, vma_node);
		if (!kref_get_unless_zero(&bo->kref))
			bo = NULL;
	}

	drm_vma_offset_unlock_lookup(&bdev->vma_manager);

	if (!bo)
		pr_err("Could not find buffer object to map\n");

	return bo;
}

int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
		struct ttm_bo_device *bdev)
{
	struct ttm_bo_driver *driver;
	struct ttm_buffer_object *bo;
	int ret;

	bo = ttm_bo_vm_lookup(bdev, vma->vm_pgoff, vma_pages(vma));
	if (unlikely(!bo))
		return -EINVAL;

	driver = bo->bdev->driver;
	if (unlikely(!driver->verify_access)) {
		ret = -EPERM;
		goto out_unref;
	}
	ret = driver->verify_access(bo, filp);
	if (unlikely(ret != 0))
		goto out_unref;

	vma->vm_ops = &ttm_bo_vm_ops;

	/*
	 * Note: We're transferring the bo reference to
	 * vma->vm_private_data here.
	 */

	vma->vm_private_data = bo;
	vma->vm_flags |= VM_IO | VM_MIXEDMAP | VM_DONTEXPAND | VM_DONTDUMP;
	return 0;
out_unref:
	ttm_bo_unref(&bo);
	return ret;
}
EXPORT_SYMBOL(ttm_bo_mmap);

int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
{
	if (vma->vm_pgoff != 0)
		return -EACCES;

	vma->vm_ops = &ttm_bo_vm_ops;
	vma->vm_private_data = ttm_bo_reference(bo);
	vma->vm_flags |= VM_IO | VM_MIXEDMAP | VM_DONTEXPAND;
	return 0;
}
EXPORT_SYMBOL(ttm_fbdev_mmap);
Commit	Line	Data
ba4e7d97 TH	1	/**************************************************************************
	2	*
	3	* Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
	4	* All Rights Reserved.
	5	*
	6	* Permission is hereby granted, free of charge, to any person obtaining a
	7	* copy of this software and associated documentation files (the
	8	* "Software"), to deal in the Software without restriction, including
	9	* without limitation the rights to use, copy, modify, merge, publish,
	10	* distribute, sub license, and/or sell copies of the Software, and to
	11	* permit persons to whom the Software is furnished to do so, subject to
	12	* the following conditions:
	13	*
	14	* The above copyright notice and this permission notice (including the
	15	* next paragraph) shall be included in all copies or substantial portions
	16	* of the Software.
	17	*
	18	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	19	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	20	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	21	* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
	22	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	23	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
	24	* USE OR OTHER DEALINGS IN THE SOFTWARE.
	25	*
	26	**************************************************************************/
	27	/*
	28	* Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
	29	*/
	30
25d0479a JP	31	#define pr_fmt(fmt) "[TTM] " fmt
25d0479a JP	32
ba4e7d97 TH	33	#include <ttm/ttm_module.h>
	34	#include <ttm/ttm_bo_driver.h>
	35	#include <ttm/ttm_placement.h>
72525b3f	36	#include <drm/drm_vma_manager.h>
ba4e7d97	37	#include <linux/mm.h>
ba4e7d97 TH	38	#include <linux/rbtree.h>
	39	#include <linux/module.h>
	40	#include <linux/uaccess.h>
	41
	42	#define TTM_BO_VM_NUM_PREFAULT 16
	43
cbe12e74 TH	44	static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo,
	45	struct vm_area_struct *vma,
	46	struct vm_fault *vmf)
	47	{
	48	struct ttm_bo_device *bdev = bo->bdev;
	49	int ret = 0;
	50
	51	spin_lock(&bdev->fence_lock);
	52	if (likely(!test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)))
	53	goto out_unlock;
	54
	55	/*
	56	* Quick non-stalling check for idle.
	57	*/
	58	ret = ttm_bo_wait(bo, false, false, true);
	59	if (likely(ret == 0))
	60	goto out_unlock;
	61
	62	/*
	63	* If possible, avoid waiting for GPU with mmap_sem
	64	* held.
	65	*/
	66	if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
	67	ret = VM_FAULT_RETRY;
	68	if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT)
	69	goto out_unlock;
	70
	71	up_read(&vma->vm_mm->mmap_sem);
	72	(void) ttm_bo_wait(bo, false, true, false);
	73	goto out_unlock;
	74	}
	75
	76	/*
	77	* Ordinary wait.
	78	*/
	79	ret = ttm_bo_wait(bo, false, true, false);
	80	if (unlikely(ret != 0))
	81	ret = (ret != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
	82	VM_FAULT_NOPAGE;
	83
	84	out_unlock:
	85	spin_unlock(&bdev->fence_lock);
	86	return ret;
	87	}
	88
ba4e7d97 TH	89	static int ttm_bo_vm_fault(struct vm_area_struct vma, struct vm_fault vmf)
	90	{
	91	struct ttm_buffer_object bo = (struct ttm_buffer_object )
	92	vma->vm_private_data;
	93	struct ttm_bo_device *bdev = bo->bdev;
ba4e7d97 TH	94	unsigned long page_offset;
	95	unsigned long page_last;
	96	unsigned long pfn;
	97	struct ttm_tt *ttm = NULL;
	98	struct page *page;
	99	int ret;
	100	int i;
ba4e7d97 TH	101	unsigned long address = (unsigned long)vmf->virtual_address;
ba4e7d97 TH	102	int retval = VM_FAULT_NOPAGE;
eba67093 TH	103	struct ttm_mem_type_manager *man =
eba67093 TH	104	&bdev->man[bo->mem.mem_type];
3943875e	105	struct vm_area_struct cvma;
ba4e7d97 TH	106
	107	/*
	108	* Work around locking order reversal in fault / nopfn
	109	* between mmap_sem and bo_reserve: Perform a trylock operation
	110	* for reserve, and if it fails, retry the fault after scheduling.
	111	*/
	112
	113	ret = ttm_bo_reserve(bo, true, true, false, 0);
	114	if (unlikely(ret != 0)) {
	115	if (ret == -EBUSY)
	116	set_need_resched();
	117	return VM_FAULT_NOPAGE;
	118	}
	119
82c5da6b JG	120	if (bdev->driver->fault_reserve_notify) {
	121	ret = bdev->driver->fault_reserve_notify(bo);
	122	switch (ret) {
	123	case 0:
	124	break;
	125	case -EBUSY:
	126	set_need_resched();
	127	case -ERESTARTSYS:
	128	retval = VM_FAULT_NOPAGE;
	129	goto out_unlock;
	130	default:
	131	retval = VM_FAULT_SIGBUS;
	132	goto out_unlock;
	133	}
	134	}
e024e110	135
ba4e7d97 TH	136	/*
	137	* Wait for buffer data in transit, due to a pipelined
	138	* move.
	139	*/
cbe12e74 TH	140	ret = ttm_bo_vm_fault_idle(bo, vma, vmf);
	141	if (unlikely(ret != 0)) {
	142	retval = ret;
	143	goto out_unlock;
	144	}
ba4e7d97	145
eba67093 TH	146	ret = ttm_mem_io_lock(man, true);
	147	if (unlikely(ret != 0)) {
	148	retval = VM_FAULT_NOPAGE;
ba4e7d97 TH	149	goto out_unlock;
ba4e7d97 TH	150	}
eba67093 TH	151	ret = ttm_mem_io_reserve_vm(bo);
	152	if (unlikely(ret != 0)) {
	153	retval = VM_FAULT_SIGBUS;
	154	goto out_io_unlock;
	155	}
ba4e7d97	156
ba4e7d97	157	page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
72525b3f	158	drm_vma_node_start(&bo->vma_node) - vma->vm_pgoff;
025df775	159	page_last = vma_pages(vma) +
72525b3f	160	drm_vma_node_start(&bo->vma_node) - vma->vm_pgoff;
ba4e7d97 TH	161
	162	if (unlikely(page_offset >= bo->num_pages)) {
	163	retval = VM_FAULT_SIGBUS;
eba67093	164	goto out_io_unlock;
ba4e7d97 TH	165	}
	166
	167	/*
3943875e TH	168	* Make a local vma copy to modify the page_prot member
	169	* and vm_flags if necessary. The vma parameter is protected
	170	* by mmap_sem in write mode.
ba4e7d97	171	*/
3943875e TH	172	cvma = *vma;
	173	cvma.vm_page_prot = vm_get_page_prot(cvma.vm_flags);
	174
82c5da6b	175	if (bo->mem.bus.is_iomem) {
3943875e TH	176	cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
3943875e TH	177	cvma.vm_page_prot);
ba4e7d97 TH	178	} else {
ba4e7d97 TH	179	ttm = bo->ttm;
3943875e TH	180	if (!(bo->mem.placement & TTM_PL_FLAG_CACHED))
	181	cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
	182	cvma.vm_page_prot);
b1e5f172 JG	183
	184	/* Allocate all page at once, most common usage */
	185	if (ttm->bdev->driver->ttm_tt_populate(ttm)) {
	186	retval = VM_FAULT_OOM;
	187	goto out_io_unlock;
	188	}
ba4e7d97 TH	189	}
	190
	191	/*
	192	* Speculatively prefault a number of pages. Only error on
	193	* first page.
	194	*/
ba4e7d97	195	for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) {
82c5da6b JG	196	if (bo->mem.bus.is_iomem)
82c5da6b JG	197	pfn = ((bo->mem.bus.base + bo->mem.bus.offset) >> PAGE_SHIFT) + page_offset;
ba4e7d97	198	else {
b1e5f172	199	page = ttm->pages[page_offset];
ba4e7d97 TH	200	if (unlikely(!page && i == 0)) {
ba4e7d97 TH	201	retval = VM_FAULT_OOM;
eba67093	202	goto out_io_unlock;
ba4e7d97 TH	203	} else if (unlikely(!page)) {
	204	break;
	205	}
	206	pfn = page_to_pfn(page);
	207	}
	208
3943875e	209	ret = vm_insert_mixed(&cvma, address, pfn);
ba4e7d97 TH	210	/*
	211	* Somebody beat us to this PTE or prefaulting to
	212	* an already populated PTE, or prefaulting error.
	213	*/
	214
	215	if (unlikely((ret == -EBUSY) \|\| (ret != 0 && i > 0)))
	216	break;
	217	else if (unlikely(ret != 0)) {
	218	retval =
	219	(ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
eba67093	220	goto out_io_unlock;
ba4e7d97 TH	221	}
	222
	223	address += PAGE_SIZE;
	224	if (unlikely(++page_offset >= page_last))
	225	break;
	226	}
eba67093 TH	227	out_io_unlock:
eba67093 TH	228	ttm_mem_io_unlock(man);
ba4e7d97 TH	229	out_unlock:
	230	ttm_bo_unreserve(bo);
	231	return retval;
	232	}
	233
	234	static void ttm_bo_vm_open(struct vm_area_struct *vma)
	235	{
	236	struct ttm_buffer_object *bo =
	237	(struct ttm_buffer_object *)vma->vm_private_data;
	238
	239	(void)ttm_bo_reference(bo);
	240	}
	241
	242	static void ttm_bo_vm_close(struct vm_area_struct *vma)
	243	{
82c5da6b	244	struct ttm_buffer_object bo = (struct ttm_buffer_object )vma->vm_private_data;
ba4e7d97 TH	245
	246	ttm_bo_unref(&bo);
	247	vma->vm_private_data = NULL;
	248	}
	249
f0f37e2f	250	static const struct vm_operations_struct ttm_bo_vm_ops = {
ba4e7d97 TH	251	.fault = ttm_bo_vm_fault,
	252	.open = ttm_bo_vm_open,
	253	.close = ttm_bo_vm_close
	254	};
	255
72525b3f DH	256	static struct ttm_buffer_object ttm_bo_vm_lookup(struct ttm_bo_device bdev,
	257	unsigned long offset,
	258	unsigned long pages)
	259	{
	260	struct drm_vma_offset_node *node;
	261	struct ttm_buffer_object *bo = NULL;
	262
	263	drm_vma_offset_lock_lookup(&bdev->vma_manager);
	264
	265	node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, pages);
	266	if (likely(node)) {
	267	bo = container_of(node, struct ttm_buffer_object, vma_node);
	268	if (!kref_get_unless_zero(&bo->kref))
	269	bo = NULL;
	270	}
	271
	272	drm_vma_offset_unlock_lookup(&bdev->vma_manager);
	273
	274	if (!bo)
	275	pr_err("Could not find buffer object to map\n");
	276
	277	return bo;
	278	}
	279
ba4e7d97 TH	280	int ttm_bo_mmap(struct file filp, struct vm_area_struct vma,
	281	struct ttm_bo_device *bdev)
	282	{
	283	struct ttm_bo_driver *driver;
	284	struct ttm_buffer_object *bo;
	285	int ret;
	286
72525b3f DH	287	bo = ttm_bo_vm_lookup(bdev, vma->vm_pgoff, vma_pages(vma));
72525b3f DH	288	if (unlikely(!bo))
ba4e7d97	289	return -EINVAL;
ba4e7d97 TH	290
	291	driver = bo->bdev->driver;
	292	if (unlikely(!driver->verify_access)) {
	293	ret = -EPERM;
	294	goto out_unref;
	295	}
	296	ret = driver->verify_access(bo, filp);
	297	if (unlikely(ret != 0))
	298	goto out_unref;
	299
	300	vma->vm_ops = &ttm_bo_vm_ops;
	301
	302	/*
	303	* Note: We're transferring the bo reference to
	304	* vma->vm_private_data here.
	305	*/
	306
	307	vma->vm_private_data = bo;
314e51b9	308	vma->vm_flags \|= VM_IO \| VM_MIXEDMAP \| VM_DONTEXPAND \| VM_DONTDUMP;
ba4e7d97 TH	309	return 0;
	310	out_unref:
	311	ttm_bo_unref(&bo);
	312	return ret;
	313	}
	314	EXPORT_SYMBOL(ttm_bo_mmap);
	315
	316	int ttm_fbdev_mmap(struct vm_area_struct vma, struct ttm_buffer_object bo)
	317	{
	318	if (vma->vm_pgoff != 0)
	319	return -EACCES;
	320
	321	vma->vm_ops = &ttm_bo_vm_ops;
	322	vma->vm_private_data = ttm_bo_reference(bo);
314e51b9	323	vma->vm_flags \|= VM_IO \| VM_MIXEDMAP \| VM_DONTEXPAND;
ba4e7d97 TH	324	return 0;
	325	}
	326	EXPORT_SYMBOL(ttm_fbdev_mmap);