[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(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];

	/*
	 * 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.
	 */

	spin_lock(&bdev->fence_lock);
	if (test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)) {
		ret = ttm_bo_wait(bo, false, true, false);
		spin_unlock(&bdev->fence_lock);
		if (unlikely(ret != 0)) {
			retval = (ret != -ERESTARTSYS) ?
			    VM_FAULT_SIGBUS : VM_FAULT_NOPAGE;
			goto out_unlock;
		}
	} else
		spin_unlock(&bdev->fence_lock);

	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;
	}

	/*
	 * Strictly, we're not allowed to modify vma->vm_page_prot here,
	 * since the mmap_sem is only held in read mode. However, we
	 * modify only the caching bits of vma->vm_page_prot and
	 * consider those bits protected by
	 * the bo->mutex, as we should be the only writers.
	 * There shouldn't really be any readers of these bits except
	 * within vm_insert_mixed()? fork?
	 *
	 * TODO: Add a list of vmas to the bo, and change the
	 * vma->vm_page_prot when the object changes caching policy, with
	 * the correct locks held.
	 */
	if (bo->mem.bus.is_iomem) {
		vma->vm_page_prot = ttm_io_prot(bo->mem.placement,
						vma->vm_page_prot);
	} else {
		ttm = bo->ttm;
		vma->vm_page_prot = (bo->mem.placement & TTM_PL_FLAG_CACHED) ?
		    vm_get_page_prot(vma->vm_flags) :
		    ttm_io_prot(bo->mem.placement, vma->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(vma, 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);


ssize_t ttm_bo_io(struct ttm_bo_device *bdev, struct file *filp,
		  const char __user *wbuf, char __user *rbuf, size_t count,
		  loff_t *f_pos, bool write)
{
	struct ttm_buffer_object *bo;
	struct ttm_bo_driver *driver;
	struct ttm_bo_kmap_obj map;
	unsigned long dev_offset = (*f_pos >> PAGE_SHIFT);
	unsigned long kmap_offset;
	unsigned long kmap_end;
	unsigned long kmap_num;
	size_t io_size;
	unsigned int page_offset;
	char *virtual;
	int ret;
	bool no_wait = false;
	bool dummy;

	bo = ttm_bo_vm_lookup(bdev, dev_offset, 1);
	if (unlikely(bo == NULL))
		return -EFAULT;

	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;

	kmap_offset = dev_offset - drm_vma_node_start(&bo->vma_node);
	if (unlikely(kmap_offset >= bo->num_pages)) {
		ret = -EFBIG;
		goto out_unref;
	}

	page_offset = *f_pos & ~PAGE_MASK;
	io_size = bo->num_pages - kmap_offset;
	io_size = (io_size << PAGE_SHIFT) - page_offset;
	if (count < io_size)
		io_size = count;

	kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
	kmap_num = kmap_end - kmap_offset + 1;

	ret = ttm_bo_reserve(bo, true, no_wait, false, 0);

	switch (ret) {
	case 0:
		break;
	case -EBUSY:
		ret = -EAGAIN;
		goto out_unref;
	default:
		goto out_unref;
	}

	ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
	if (unlikely(ret != 0)) {
		ttm_bo_unreserve(bo);
		goto out_unref;
	}

	virtual = ttm_kmap_obj_virtual(&map, &dummy);
	virtual += page_offset;

	if (write)
		ret = copy_from_user(virtual, wbuf, io_size);
	else
		ret = copy_to_user(rbuf, virtual, io_size);

	ttm_bo_kunmap(&map);
	ttm_bo_unreserve(bo);
	ttm_bo_unref(&bo);

	if (unlikely(ret != 0))
		return -EFBIG;

	*f_pos += io_size;

	return io_size;
out_unref:
	ttm_bo_unref(&bo);
	return ret;
}

ssize_t ttm_bo_fbdev_io(struct ttm_buffer_object *bo, const char __user *wbuf,
			char __user *rbuf, size_t count, loff_t *f_pos,
			bool write)
{
	struct ttm_bo_kmap_obj map;
	unsigned long kmap_offset;
	unsigned long kmap_end;
	unsigned long kmap_num;
	size_t io_size;
	unsigned int page_offset;
	char *virtual;
	int ret;
	bool no_wait = false;
	bool dummy;

	kmap_offset = (*f_pos >> PAGE_SHIFT);
	if (unlikely(kmap_offset >= bo->num_pages))
		return -EFBIG;

	page_offset = *f_pos & ~PAGE_MASK;
	io_size = bo->num_pages - kmap_offset;
	io_size = (io_size << PAGE_SHIFT) - page_offset;
	if (count < io_size)
		io_size = count;

	kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
	kmap_num = kmap_end - kmap_offset + 1;

	ret = ttm_bo_reserve(bo, true, no_wait, false, 0);

	switch (ret) {
	case 0:
		break;
	case -EBUSY:
		return -EAGAIN;
	default:
		return ret;
	}

	ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
	if (unlikely(ret != 0)) {
		ttm_bo_unreserve(bo);
		return ret;
	}

	virtual = ttm_kmap_obj_virtual(&map, &dummy);
	virtual += page_offset;

	if (write)
		ret = copy_from_user(virtual, wbuf, io_size);
	else
		ret = copy_to_user(rbuf, virtual, io_size);

	ttm_bo_kunmap(&map);
	ttm_bo_unreserve(bo);
	ttm_bo_unref(&bo);

	if (unlikely(ret != 0))
		return ret;

	*f_pos += io_size;

	return io_size;
}
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
ba4e7d97 TH	44	static int ttm_bo_vm_fault(struct vm_area_struct vma, struct vm_fault vmf)
	45	{
	46	struct ttm_buffer_object bo = (struct ttm_buffer_object )
	47	vma->vm_private_data;
	48	struct ttm_bo_device *bdev = bo->bdev;
ba4e7d97 TH	49	unsigned long page_offset;
	50	unsigned long page_last;
	51	unsigned long pfn;
	52	struct ttm_tt *ttm = NULL;
	53	struct page *page;
	54	int ret;
	55	int i;
ba4e7d97 TH	56	unsigned long address = (unsigned long)vmf->virtual_address;
ba4e7d97 TH	57	int retval = VM_FAULT_NOPAGE;
eba67093 TH	58	struct ttm_mem_type_manager *man =
eba67093 TH	59	&bdev->man[bo->mem.mem_type];
ba4e7d97 TH	60
	61	/*
	62	* Work around locking order reversal in fault / nopfn
	63	* between mmap_sem and bo_reserve: Perform a trylock operation
	64	* for reserve, and if it fails, retry the fault after scheduling.
	65	*/
	66
	67	ret = ttm_bo_reserve(bo, true, true, false, 0);
	68	if (unlikely(ret != 0)) {
	69	if (ret == -EBUSY)
	70	set_need_resched();
	71	return VM_FAULT_NOPAGE;
	72	}
	73
82c5da6b JG	74	if (bdev->driver->fault_reserve_notify) {
	75	ret = bdev->driver->fault_reserve_notify(bo);
	76	switch (ret) {
	77	case 0:
	78	break;
	79	case -EBUSY:
	80	set_need_resched();
	81	case -ERESTARTSYS:
	82	retval = VM_FAULT_NOPAGE;
	83	goto out_unlock;
	84	default:
	85	retval = VM_FAULT_SIGBUS;
	86	goto out_unlock;
	87	}
	88	}
e024e110	89
ba4e7d97 TH	90	/*
	91	* Wait for buffer data in transit, due to a pipelined
	92	* move.
	93	*/
	94
702adba2	95	spin_lock(&bdev->fence_lock);
ba4e7d97 TH	96	if (test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)) {
ba4e7d97 TH	97	ret = ttm_bo_wait(bo, false, true, false);
702adba2	98	spin_unlock(&bdev->fence_lock);
ba4e7d97	99	if (unlikely(ret != 0)) {
98ffc415	100	retval = (ret != -ERESTARTSYS) ?
ba4e7d97 TH	101	VM_FAULT_SIGBUS : VM_FAULT_NOPAGE;
	102	goto out_unlock;
	103	}
	104	} else
702adba2	105	spin_unlock(&bdev->fence_lock);
ba4e7d97	106
eba67093 TH	107	ret = ttm_mem_io_lock(man, true);
	108	if (unlikely(ret != 0)) {
	109	retval = VM_FAULT_NOPAGE;
ba4e7d97 TH	110	goto out_unlock;
ba4e7d97 TH	111	}
eba67093 TH	112	ret = ttm_mem_io_reserve_vm(bo);
	113	if (unlikely(ret != 0)) {
	114	retval = VM_FAULT_SIGBUS;
	115	goto out_io_unlock;
	116	}
ba4e7d97	117
ba4e7d97	118	page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
72525b3f	119	drm_vma_node_start(&bo->vma_node) - vma->vm_pgoff;
025df775	120	page_last = vma_pages(vma) +
72525b3f	121	drm_vma_node_start(&bo->vma_node) - vma->vm_pgoff;
ba4e7d97 TH	122
	123	if (unlikely(page_offset >= bo->num_pages)) {
	124	retval = VM_FAULT_SIGBUS;
eba67093	125	goto out_io_unlock;
ba4e7d97 TH	126	}
	127
	128	/*
	129	* Strictly, we're not allowed to modify vma->vm_page_prot here,
	130	* since the mmap_sem is only held in read mode. However, we
	131	* modify only the caching bits of vma->vm_page_prot and
	132	* consider those bits protected by
	133	* the bo->mutex, as we should be the only writers.
	134	* There shouldn't really be any readers of these bits except
	135	* within vm_insert_mixed()? fork?
	136	*
	137	* TODO: Add a list of vmas to the bo, and change the
	138	* vma->vm_page_prot when the object changes caching policy, with
	139	* the correct locks held.
	140	*/
82c5da6b	141	if (bo->mem.bus.is_iomem) {
ba4e7d97 TH	142	vma->vm_page_prot = ttm_io_prot(bo->mem.placement,
	143	vma->vm_page_prot);
	144	} else {
	145	ttm = bo->ttm;
	146	vma->vm_page_prot = (bo->mem.placement & TTM_PL_FLAG_CACHED) ?
	147	vm_get_page_prot(vma->vm_flags) :
	148	ttm_io_prot(bo->mem.placement, vma->vm_page_prot);
b1e5f172 JG	149
	150	/* Allocate all page at once, most common usage */
	151	if (ttm->bdev->driver->ttm_tt_populate(ttm)) {
	152	retval = VM_FAULT_OOM;
	153	goto out_io_unlock;
	154	}
ba4e7d97 TH	155	}
	156
	157	/*
	158	* Speculatively prefault a number of pages. Only error on
	159	* first page.
	160	*/
ba4e7d97	161	for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) {
82c5da6b JG	162	if (bo->mem.bus.is_iomem)
82c5da6b JG	163	pfn = ((bo->mem.bus.base + bo->mem.bus.offset) >> PAGE_SHIFT) + page_offset;
ba4e7d97	164	else {
b1e5f172	165	page = ttm->pages[page_offset];
ba4e7d97 TH	166	if (unlikely(!page && i == 0)) {
ba4e7d97 TH	167	retval = VM_FAULT_OOM;
eba67093	168	goto out_io_unlock;
ba4e7d97 TH	169	} else if (unlikely(!page)) {
	170	break;
	171	}
	172	pfn = page_to_pfn(page);
	173	}
	174
	175	ret = vm_insert_mixed(vma, address, pfn);
	176	/*
	177	* Somebody beat us to this PTE or prefaulting to
	178	* an already populated PTE, or prefaulting error.
	179	*/
	180
	181	if (unlikely((ret == -EBUSY) \|\| (ret != 0 && i > 0)))
	182	break;
	183	else if (unlikely(ret != 0)) {
	184	retval =
	185	(ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
eba67093	186	goto out_io_unlock;
ba4e7d97 TH	187	}
	188
	189	address += PAGE_SIZE;
	190	if (unlikely(++page_offset >= page_last))
	191	break;
	192	}
eba67093 TH	193	out_io_unlock:
eba67093 TH	194	ttm_mem_io_unlock(man);
ba4e7d97 TH	195	out_unlock:
	196	ttm_bo_unreserve(bo);
	197	return retval;
	198	}
	199
	200	static void ttm_bo_vm_open(struct vm_area_struct *vma)
	201	{
	202	struct ttm_buffer_object *bo =
	203	(struct ttm_buffer_object *)vma->vm_private_data;
	204
	205	(void)ttm_bo_reference(bo);
	206	}
	207
	208	static void ttm_bo_vm_close(struct vm_area_struct *vma)
	209	{
82c5da6b	210	struct ttm_buffer_object bo = (struct ttm_buffer_object )vma->vm_private_data;
ba4e7d97 TH	211
	212	ttm_bo_unref(&bo);
	213	vma->vm_private_data = NULL;
	214	}
	215
f0f37e2f	216	static const struct vm_operations_struct ttm_bo_vm_ops = {
ba4e7d97 TH	217	.fault = ttm_bo_vm_fault,
	218	.open = ttm_bo_vm_open,
	219	.close = ttm_bo_vm_close
	220	};
	221
72525b3f DH	222	static struct ttm_buffer_object ttm_bo_vm_lookup(struct ttm_bo_device bdev,
	223	unsigned long offset,
	224	unsigned long pages)
	225	{
	226	struct drm_vma_offset_node *node;
	227	struct ttm_buffer_object *bo = NULL;
	228
	229	drm_vma_offset_lock_lookup(&bdev->vma_manager);
	230
	231	node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, pages);
	232	if (likely(node)) {
	233	bo = container_of(node, struct ttm_buffer_object, vma_node);
	234	if (!kref_get_unless_zero(&bo->kref))
	235	bo = NULL;
	236	}
	237
	238	drm_vma_offset_unlock_lookup(&bdev->vma_manager);
	239
	240	if (!bo)
	241	pr_err("Could not find buffer object to map\n");
	242
	243	return bo;
	244	}
	245
ba4e7d97 TH	246	int ttm_bo_mmap(struct file filp, struct vm_area_struct vma,
	247	struct ttm_bo_device *bdev)
	248	{
	249	struct ttm_bo_driver *driver;
	250	struct ttm_buffer_object *bo;
	251	int ret;
	252
72525b3f DH	253	bo = ttm_bo_vm_lookup(bdev, vma->vm_pgoff, vma_pages(vma));
72525b3f DH	254	if (unlikely(!bo))
ba4e7d97	255	return -EINVAL;
ba4e7d97 TH	256
	257	driver = bo->bdev->driver;
	258	if (unlikely(!driver->verify_access)) {
	259	ret = -EPERM;
	260	goto out_unref;
	261	}
	262	ret = driver->verify_access(bo, filp);
	263	if (unlikely(ret != 0))
	264	goto out_unref;
	265
	266	vma->vm_ops = &ttm_bo_vm_ops;
	267
	268	/*
	269	* Note: We're transferring the bo reference to
	270	* vma->vm_private_data here.
	271	*/
	272
	273	vma->vm_private_data = bo;
314e51b9	274	vma->vm_flags \|= VM_IO \| VM_MIXEDMAP \| VM_DONTEXPAND \| VM_DONTDUMP;
ba4e7d97 TH	275	return 0;
	276	out_unref:
	277	ttm_bo_unref(&bo);
	278	return ret;
	279	}
	280	EXPORT_SYMBOL(ttm_bo_mmap);
	281
	282	int ttm_fbdev_mmap(struct vm_area_struct vma, struct ttm_buffer_object bo)
	283	{
	284	if (vma->vm_pgoff != 0)
	285	return -EACCES;
	286
	287	vma->vm_ops = &ttm_bo_vm_ops;
	288	vma->vm_private_data = ttm_bo_reference(bo);
314e51b9	289	vma->vm_flags \|= VM_IO \| VM_MIXEDMAP \| VM_DONTEXPAND;
ba4e7d97 TH	290	return 0;
	291	}
	292	EXPORT_SYMBOL(ttm_fbdev_mmap);
	293
	294
	295	ssize_t ttm_bo_io(struct ttm_bo_device bdev, struct file filp,
	296	const char __user wbuf, char __user rbuf, size_t count,
	297	loff_t *f_pos, bool write)
	298	{
	299	struct ttm_buffer_object *bo;
	300	struct ttm_bo_driver *driver;
	301	struct ttm_bo_kmap_obj map;
	302	unsigned long dev_offset = (*f_pos >> PAGE_SHIFT);
	303	unsigned long kmap_offset;
	304	unsigned long kmap_end;
	305	unsigned long kmap_num;
	306	size_t io_size;
	307	unsigned int page_offset;
	308	char *virtual;
	309	int ret;
	310	bool no_wait = false;
	311	bool dummy;
	312
72525b3f	313	bo = ttm_bo_vm_lookup(bdev, dev_offset, 1);
ba4e7d97 TH	314	if (unlikely(bo == NULL))
	315	return -EFAULT;
	316
	317	driver = bo->bdev->driver;
b8ff7357	318	if (unlikely(!driver->verify_access)) {
ba4e7d97 TH	319	ret = -EPERM;
	320	goto out_unref;
	321	}
	322
	323	ret = driver->verify_access(bo, filp);
	324	if (unlikely(ret != 0))
	325	goto out_unref;
	326
72525b3f	327	kmap_offset = dev_offset - drm_vma_node_start(&bo->vma_node);
916635bf	328	if (unlikely(kmap_offset >= bo->num_pages)) {
ba4e7d97 TH	329	ret = -EFBIG;
	330	goto out_unref;
	331	}
	332
	333	page_offset = *f_pos & ~PAGE_MASK;
	334	io_size = bo->num_pages - kmap_offset;
	335	io_size = (io_size << PAGE_SHIFT) - page_offset;
	336	if (count < io_size)
	337	io_size = count;
	338
	339	kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
	340	kmap_num = kmap_end - kmap_offset + 1;
	341
	342	ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
	343
	344	switch (ret) {
	345	case 0:
	346	break;
ba4e7d97 TH	347	case -EBUSY:
	348	ret = -EAGAIN;
	349	goto out_unref;
	350	default:
	351	goto out_unref;
	352	}
	353
	354	ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
	355	if (unlikely(ret != 0)) {
	356	ttm_bo_unreserve(bo);
	357	goto out_unref;
	358	}
	359
	360	virtual = ttm_kmap_obj_virtual(&map, &dummy);
	361	virtual += page_offset;
	362
	363	if (write)
	364	ret = copy_from_user(virtual, wbuf, io_size);
	365	else
	366	ret = copy_to_user(rbuf, virtual, io_size);
	367
	368	ttm_bo_kunmap(&map);
	369	ttm_bo_unreserve(bo);
	370	ttm_bo_unref(&bo);
	371
	372	if (unlikely(ret != 0))
	373	return -EFBIG;
	374
	375	*f_pos += io_size;
	376
	377	return io_size;
	378	out_unref:
	379	ttm_bo_unref(&bo);
	380	return ret;
	381	}
	382
	383	ssize_t ttm_bo_fbdev_io(struct ttm_buffer_object bo, const char __user wbuf,
	384	char __user rbuf, size_t count, loff_t f_pos,
	385	bool write)
	386	{
	387	struct ttm_bo_kmap_obj map;
	388	unsigned long kmap_offset;
	389	unsigned long kmap_end;
	390	unsigned long kmap_num;
	391	size_t io_size;
	392	unsigned int page_offset;
	393	char *virtual;
	394	int ret;
	395	bool no_wait = false;
	396	bool dummy;
	397
	398	kmap_offset = (*f_pos >> PAGE_SHIFT);
916635bf	399	if (unlikely(kmap_offset >= bo->num_pages))
ba4e7d97 TH	400	return -EFBIG;
	401
	402	page_offset = *f_pos & ~PAGE_MASK;
	403	io_size = bo->num_pages - kmap_offset;
	404	io_size = (io_size << PAGE_SHIFT) - page_offset;
	405	if (count < io_size)
	406	io_size = count;
	407
	408	kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
	409	kmap_num = kmap_end - kmap_offset + 1;
	410
	411	ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
	412
	413	switch (ret) {
	414	case 0:
	415	break;
ba4e7d97 TH	416	case -EBUSY:
	417	return -EAGAIN;
	418	default:
	419	return ret;
	420	}
	421
	422	ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
	423	if (unlikely(ret != 0)) {
	424	ttm_bo_unreserve(bo);
	425	return ret;
	426	}
	427
	428	virtual = ttm_kmap_obj_virtual(&map, &dummy);
	429	virtual += page_offset;
	430
	431	if (write)
	432	ret = copy_from_user(virtual, wbuf, io_size);
	433	else
	434	ret = copy_to_user(rbuf, virtual, io_size);
	435
	436	ttm_bo_kunmap(&map);
	437	ttm_bo_unreserve(bo);
	438	ttm_bo_unref(&bo);
	439
	440	if (unlikely(ret != 0))
	441	return ret;
	442
	443	*f_pos += io_size;
	444
	445	return io_size;
	446	}