[mirror_ubuntu-bionic-kernel.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/pfn_t.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_fault *vmf)
{
	int ret = 0;

	if (likely(!bo->moving))
		goto out_unlock;

	/*
	 * Quick non-stalling check for idle.
	 */
	if (dma_fence_is_signaled(bo->moving))
		goto out_clear;

	/*
	 * 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;

		ttm_bo_reference(bo);
		up_read(&vmf->vma->vm_mm->mmap_sem);
		(void) dma_fence_wait(bo->moving, true);
		ttm_bo_unreserve(bo);
		ttm_bo_unref(&bo);
		goto out_unlock;
	}

	/*
	 * Ordinary wait.
	 */
	ret = dma_fence_wait(bo->moving, true);
	if (unlikely(ret != 0)) {
		ret = (ret != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
			VM_FAULT_NOPAGE;
		goto out_unlock;
	}

out_clear:
	dma_fence_put(bo->moving);
	bo->moving = NULL;

out_unlock:
	return ret;
}

static int ttm_bo_vm_fault(struct vm_fault *vmf)
{
	struct vm_area_struct *vma = vmf->vma;
	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 = vmf->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 waiting
	 * for the buffer to become unreserved.
	 */
	ret = ttm_bo_reserve(bo, true, true, NULL);
	if (unlikely(ret != 0)) {
		if (ret != -EBUSY)
			return VM_FAULT_NOPAGE;

		if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
			if (!(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) {
				ttm_bo_reference(bo);
				up_read(&vmf->vma->vm_mm->mmap_sem);
				(void) ttm_bo_wait_unreserved(bo);
				ttm_bo_unref(&bo);
			}

			return VM_FAULT_RETRY;
		}

		/*
		 * If we'd want to change locking order to
		 * mmap_sem -> bo::reserve, we'd use a blocking reserve here
		 * instead of retrying the fault...
		 */
		return VM_FAULT_NOPAGE;
	}

	/*
	 * Refuse to fault imported pages. This should be handled
	 * (if at all) by redirecting mmap to the exporter.
	 */
	if (bo->ttm && (bo->ttm->page_flags & TTM_PAGE_FLAG_SG)) {
		retval = VM_FAULT_SIGBUS;
		goto out_unlock;
	}

	if (bdev->driver->fault_reserve_notify) {
		ret = bdev->driver->fault_reserve_notify(bo);
		switch (ret) {
		case 0:
			break;
		case -EBUSY:
		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, vmf);
	if (unlikely(ret != 0)) {
		retval = ret;

		if (retval == VM_FAULT_RETRY &&
		    !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) {
			/* The BO has already been unreserved. */
			return retval;
		}

		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) +
		vma->vm_pgoff - drm_vma_node_start(&bo->vma_node);
	page_last = vma_pages(vma) + vma->vm_pgoff -
		drm_vma_node_start(&bo->vma_node);

	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;
		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;
			}
			page->mapping = vma->vm_file->f_mapping;
			page->index = drm_vma_node_start(&bo->vma_node) +
				page_offset;
			pfn = page_to_pfn(page);
		}

		if (vma->vm_flags & VM_MIXEDMAP)
			ret = vm_insert_mixed(&cvma, address,
					__pfn_to_pfn_t(pfn, PFN_DEV));
		else
			ret = vm_insert_pfn(&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;

	WARN_ON(bo->bdev->dev_mapping != vma->vm_file->f_mapping);

	(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;

	/*
	 * We'd like to use VM_PFNMAP on shared mappings, where
	 * (vma->vm_flags & VM_SHARED) != 0, for performance reasons,
	 * but for some reason VM_PFNMAP + x86 PAT + write-combine is very
	 * bad for performance. Until that has been sorted out, use
	 * VM_MIXEDMAP on all mappings. See freedesktop.org bug #75719
	 */
	vma->vm_flags |= VM_MIXEDMAP;
	vma->vm_flags |= VM_IO | 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_MIXEDMAP;
	vma->vm_flags |= VM_IO | 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>
01c8f1c4	38	#include <linux/pfn_t.h>
ba4e7d97 TH	39	#include <linux/rbtree.h>
	40	#include <linux/module.h>
	41	#include <linux/uaccess.h>
	42
	43	#define TTM_BO_VM_NUM_PREFAULT 16
	44
cbe12e74	45	static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo,
cbe12e74 TH	46	struct vm_fault *vmf)
cbe12e74 TH	47	{
cbe12e74 TH	48	int ret = 0;
cbe12e74 TH	49
5bc73067	50	if (likely(!bo->moving))
cbe12e74 TH	51	goto out_unlock;
	52
	53	/*
	54	* Quick non-stalling check for idle.
	55	*/
f54d1867	56	if (dma_fence_is_signaled(bo->moving))
5bc73067	57	goto out_clear;
cbe12e74 TH	58
	59	/*
	60	* If possible, avoid waiting for GPU with mmap_sem
	61	* held.
	62	*/
	63	if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
	64	ret = VM_FAULT_RETRY;
	65	if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT)
	66	goto out_unlock;
	67
3089c1df	68	ttm_bo_reference(bo);
11bac800	69	up_read(&vmf->vma->vm_mm->mmap_sem);
f54d1867	70	(void) dma_fence_wait(bo->moving, true);
3089c1df NH	71	ttm_bo_unreserve(bo);
3089c1df NH	72	ttm_bo_unref(&bo);
cbe12e74 TH	73	goto out_unlock;
	74	}
	75
	76	/*
	77	* Ordinary wait.
	78	*/
f54d1867	79	ret = dma_fence_wait(bo->moving, true);
5bc73067	80	if (unlikely(ret != 0)) {
cbe12e74 TH	81	ret = (ret != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
cbe12e74 TH	82	VM_FAULT_NOPAGE;
5bc73067 CK	83	goto out_unlock;
	84	}
	85
	86	out_clear:
f54d1867	87	dma_fence_put(bo->moving);
5bc73067	88	bo->moving = NULL;
cbe12e74 TH	89
cbe12e74 TH	90	out_unlock:
cbe12e74 TH	91	return ret;
	92	}
	93
11bac800	94	static int ttm_bo_vm_fault(struct vm_fault *vmf)
ba4e7d97	95	{
11bac800	96	struct vm_area_struct *vma = vmf->vma;
ba4e7d97 TH	97	struct ttm_buffer_object bo = (struct ttm_buffer_object )
	98	vma->vm_private_data;
	99	struct ttm_bo_device *bdev = bo->bdev;
ba4e7d97 TH	100	unsigned long page_offset;
	101	unsigned long page_last;
	102	unsigned long pfn;
	103	struct ttm_tt *ttm = NULL;
	104	struct page *page;
	105	int ret;
	106	int i;
1a29d85e	107	unsigned long address = vmf->address;
ba4e7d97	108	int retval = VM_FAULT_NOPAGE;
eba67093 TH	109	struct ttm_mem_type_manager *man =
eba67093 TH	110	&bdev->man[bo->mem.mem_type];
3943875e	111	struct vm_area_struct cvma;
ba4e7d97 TH	112
	113	/*
	114	* Work around locking order reversal in fault / nopfn
	115	* between mmap_sem and bo_reserve: Perform a trylock operation
c58f009e TH	116	* for reserve, and if it fails, retry the fault after waiting
c58f009e TH	117	* for the buffer to become unreserved.
ba4e7d97	118	*/
dfd5e50e	119	ret = ttm_bo_reserve(bo, true, true, NULL);
ba4e7d97	120	if (unlikely(ret != 0)) {
c58f009e TH	121	if (ret != -EBUSY)
	122	return VM_FAULT_NOPAGE;
	123
	124	if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
	125	if (!(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) {
3089c1df	126	ttm_bo_reference(bo);
11bac800	127	up_read(&vmf->vma->vm_mm->mmap_sem);
c58f009e	128	(void) ttm_bo_wait_unreserved(bo);
3089c1df	129	ttm_bo_unref(&bo);
c58f009e TH	130	}
	131
	132	return VM_FAULT_RETRY;
	133	}
	134
	135	/*
	136	* If we'd want to change locking order to
	137	* mmap_sem -> bo::reserve, we'd use a blocking reserve here
	138	* instead of retrying the fault...
	139	*/
ba4e7d97 TH	140	return VM_FAULT_NOPAGE;
	141	}
	142
667a50db TH	143	/*
	144	* Refuse to fault imported pages. This should be handled
	145	* (if at all) by redirecting mmap to the exporter.
	146	*/
	147	if (bo->ttm && (bo->ttm->page_flags & TTM_PAGE_FLAG_SG)) {
	148	retval = VM_FAULT_SIGBUS;
	149	goto out_unlock;
	150	}
	151
82c5da6b JG	152	if (bdev->driver->fault_reserve_notify) {
	153	ret = bdev->driver->fault_reserve_notify(bo);
	154	switch (ret) {
	155	case 0:
	156	break;
	157	case -EBUSY:
82c5da6b JG	158	case -ERESTARTSYS:
	159	retval = VM_FAULT_NOPAGE;
	160	goto out_unlock;
	161	default:
	162	retval = VM_FAULT_SIGBUS;
	163	goto out_unlock;
	164	}
	165	}
e024e110	166
ba4e7d97 TH	167	/*
	168	* Wait for buffer data in transit, due to a pipelined
	169	* move.
	170	*/
11bac800	171	ret = ttm_bo_vm_fault_idle(bo, vmf);
cbe12e74 TH	172	if (unlikely(ret != 0)) {
cbe12e74 TH	173	retval = ret;
3089c1df NH	174
	175	if (retval == VM_FAULT_RETRY &&
	176	!(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) {
	177	/* The BO has already been unreserved. */
	178	return retval;
	179	}
	180
cbe12e74 TH	181	goto out_unlock;
cbe12e74 TH	182	}
ba4e7d97	183
eba67093 TH	184	ret = ttm_mem_io_lock(man, true);
	185	if (unlikely(ret != 0)) {
	186	retval = VM_FAULT_NOPAGE;
ba4e7d97 TH	187	goto out_unlock;
ba4e7d97 TH	188	}
eba67093 TH	189	ret = ttm_mem_io_reserve_vm(bo);
	190	if (unlikely(ret != 0)) {
	191	retval = VM_FAULT_SIGBUS;
	192	goto out_io_unlock;
	193	}
ba4e7d97	194
ba4e7d97	195	page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
d3867355 TH	196	vma->vm_pgoff - drm_vma_node_start(&bo->vma_node);
	197	page_last = vma_pages(vma) + vma->vm_pgoff -
	198	drm_vma_node_start(&bo->vma_node);
ba4e7d97 TH	199
	200	if (unlikely(page_offset >= bo->num_pages)) {
	201	retval = VM_FAULT_SIGBUS;
eba67093	202	goto out_io_unlock;
ba4e7d97 TH	203	}
	204
	205	/*
3943875e TH	206	* Make a local vma copy to modify the page_prot member
	207	* and vm_flags if necessary. The vma parameter is protected
	208	* by mmap_sem in write mode.
ba4e7d97	209	*/
3943875e TH	210	cvma = *vma;
	211	cvma.vm_page_prot = vm_get_page_prot(cvma.vm_flags);
	212
82c5da6b	213	if (bo->mem.bus.is_iomem) {
3943875e TH	214	cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
3943875e TH	215	cvma.vm_page_prot);
ba4e7d97 TH	216	} else {
ba4e7d97 TH	217	ttm = bo->ttm;
94318d50 BH	218	cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
94318d50 BH	219	cvma.vm_page_prot);
b1e5f172 JG	220
	221	/* Allocate all page at once, most common usage */
	222	if (ttm->bdev->driver->ttm_tt_populate(ttm)) {
	223	retval = VM_FAULT_OOM;
	224	goto out_io_unlock;
	225	}
ba4e7d97 TH	226	}
	227
	228	/*
	229	* Speculatively prefault a number of pages. Only error on
	230	* first page.
	231	*/
ba4e7d97	232	for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) {
82c5da6b JG	233	if (bo->mem.bus.is_iomem)
82c5da6b JG	234	pfn = ((bo->mem.bus.base + bo->mem.bus.offset) >> PAGE_SHIFT) + page_offset;
ba4e7d97	235	else {
b1e5f172	236	page = ttm->pages[page_offset];
ba4e7d97 TH	237	if (unlikely(!page && i == 0)) {
ba4e7d97 TH	238	retval = VM_FAULT_OOM;
eba67093	239	goto out_io_unlock;
ba4e7d97 TH	240	} else if (unlikely(!page)) {
	241	break;
	242	}
58aa6622 TH	243	page->mapping = vma->vm_file->f_mapping;
	244	page->index = drm_vma_node_start(&bo->vma_node) +
	245	page_offset;
ba4e7d97 TH	246	pfn = page_to_pfn(page);
	247	}
	248
7dfe8b61	249	if (vma->vm_flags & VM_MIXEDMAP)
01c8f1c4 DW	250	ret = vm_insert_mixed(&cvma, address,
01c8f1c4 DW	251	__pfn_to_pfn_t(pfn, PFN_DEV));
7dfe8b61 TH	252	else
	253	ret = vm_insert_pfn(&cvma, address, pfn);
	254
ba4e7d97 TH	255	/*
	256	* Somebody beat us to this PTE or prefaulting to
	257	* an already populated PTE, or prefaulting error.
	258	*/
	259
	260	if (unlikely((ret == -EBUSY) \|\| (ret != 0 && i > 0)))
	261	break;
	262	else if (unlikely(ret != 0)) {
	263	retval =
	264	(ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
eba67093	265	goto out_io_unlock;
ba4e7d97 TH	266	}
	267
	268	address += PAGE_SIZE;
	269	if (unlikely(++page_offset >= page_last))
	270	break;
	271	}
eba67093 TH	272	out_io_unlock:
eba67093 TH	273	ttm_mem_io_unlock(man);
ba4e7d97 TH	274	out_unlock:
	275	ttm_bo_unreserve(bo);
	276	return retval;
	277	}
	278
	279	static void ttm_bo_vm_open(struct vm_area_struct *vma)
	280	{
	281	struct ttm_buffer_object *bo =
	282	(struct ttm_buffer_object *)vma->vm_private_data;
	283
58aa6622 TH	284	WARN_ON(bo->bdev->dev_mapping != vma->vm_file->f_mapping);
58aa6622 TH	285
ba4e7d97 TH	286	(void)ttm_bo_reference(bo);
	287	}
	288
	289	static void ttm_bo_vm_close(struct vm_area_struct *vma)
	290	{
82c5da6b	291	struct ttm_buffer_object bo = (struct ttm_buffer_object )vma->vm_private_data;
ba4e7d97 TH	292
	293	ttm_bo_unref(&bo);
	294	vma->vm_private_data = NULL;
	295	}
	296
f0f37e2f	297	static const struct vm_operations_struct ttm_bo_vm_ops = {
ba4e7d97 TH	298	.fault = ttm_bo_vm_fault,
	299	.open = ttm_bo_vm_open,
	300	.close = ttm_bo_vm_close
	301	};
	302
72525b3f DH	303	static struct ttm_buffer_object ttm_bo_vm_lookup(struct ttm_bo_device bdev,
	304	unsigned long offset,
	305	unsigned long pages)
	306	{
	307	struct drm_vma_offset_node *node;
	308	struct ttm_buffer_object *bo = NULL;
	309
	310	drm_vma_offset_lock_lookup(&bdev->vma_manager);
	311
	312	node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, pages);
	313	if (likely(node)) {
	314	bo = container_of(node, struct ttm_buffer_object, vma_node);
	315	if (!kref_get_unless_zero(&bo->kref))
	316	bo = NULL;
	317	}
	318
	319	drm_vma_offset_unlock_lookup(&bdev->vma_manager);
	320
	321	if (!bo)
	322	pr_err("Could not find buffer object to map\n");
	323
	324	return bo;
	325	}
	326
ba4e7d97 TH	327	int ttm_bo_mmap(struct file filp, struct vm_area_struct vma,
	328	struct ttm_bo_device *bdev)
	329	{
	330	struct ttm_bo_driver *driver;
	331	struct ttm_buffer_object *bo;
	332	int ret;
	333
72525b3f DH	334	bo = ttm_bo_vm_lookup(bdev, vma->vm_pgoff, vma_pages(vma));
72525b3f DH	335	if (unlikely(!bo))
ba4e7d97	336	return -EINVAL;
ba4e7d97 TH	337
	338	driver = bo->bdev->driver;
	339	if (unlikely(!driver->verify_access)) {
	340	ret = -EPERM;
	341	goto out_unref;
	342	}
	343	ret = driver->verify_access(bo, filp);
	344	if (unlikely(ret != 0))
	345	goto out_unref;
	346
	347	vma->vm_ops = &ttm_bo_vm_ops;
	348
	349	/*
	350	* Note: We're transferring the bo reference to
	351	* vma->vm_private_data here.
	352	*/
	353
	354	vma->vm_private_data = bo;
7dfe8b61 TH	355
7dfe8b61 TH	356	/*
0e6d6ec0 TH	357	* We'd like to use VM_PFNMAP on shared mappings, where
	358	* (vma->vm_flags & VM_SHARED) != 0, for performance reasons,
	359	* but for some reason VM_PFNMAP + x86 PAT + write-combine is very
	360	* bad for performance. Until that has been sorted out, use
	361	* VM_MIXEDMAP on all mappings. See freedesktop.org bug #75719
7dfe8b61	362	*/
0e6d6ec0	363	vma->vm_flags \|= VM_MIXEDMAP;
7dfe8b61	364	vma->vm_flags \|= VM_IO \| VM_DONTEXPAND \| VM_DONTDUMP;
ba4e7d97 TH	365	return 0;
	366	out_unref:
	367	ttm_bo_unref(&bo);
	368	return ret;
	369	}
	370	EXPORT_SYMBOL(ttm_bo_mmap);
	371
	372	int ttm_fbdev_mmap(struct vm_area_struct vma, struct ttm_buffer_object bo)
	373	{
	374	if (vma->vm_pgoff != 0)
	375	return -EACCES;
	376
	377	vma->vm_ops = &ttm_bo_vm_ops;
	378	vma->vm_private_data = ttm_bo_reference(bo);
0e6d6ec0	379	vma->vm_flags \|= VM_MIXEDMAP;
7dfe8b61	380	vma->vm_flags \|= VM_IO \| VM_DONTEXPAND;
ba4e7d97 TH	381	return 0;
	382	}
	383	EXPORT_SYMBOL(ttm_fbdev_mmap);