[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>
 */

#include <ttm/ttm_module.h>
#include <ttm/ttm_bo_driver.h>
#include <ttm/ttm_placement.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 struct ttm_buffer_object *ttm_bo_vm_lookup_rb(struct ttm_bo_device *bdev,
						     unsigned long page_start,
						     unsigned long num_pages)
{
	struct rb_node *cur = bdev->addr_space_rb.rb_node;
	unsigned long cur_offset;
	struct ttm_buffer_object *bo;
	struct ttm_buffer_object *best_bo = NULL;

	while (likely(cur != NULL)) {
		bo = rb_entry(cur, struct ttm_buffer_object, vm_rb);
		cur_offset = bo->vm_node->start;
		if (page_start >= cur_offset) {
			cur = cur->rb_right;
			best_bo = bo;
			if (page_start == cur_offset)
				break;
		} else
			cur = cur->rb_left;
	}

	if (unlikely(best_bo == NULL))
		return NULL;

	if (unlikely((best_bo->vm_node->start + best_bo->num_pages) <
		     (page_start + num_pages)))
		return NULL;

	return best_bo;
}

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) +
	    bo->vm_node->start - vma->vm_pgoff;
	page_last = ((vma->vm_end - vma->vm_start) >> PAGE_SHIFT) +
	    bo->vm_node->start - 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
};

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;

	read_lock(&bdev->vm_lock);
	bo = ttm_bo_vm_lookup_rb(bdev, vma->vm_pgoff,
				 (vma->vm_end - vma->vm_start) >> PAGE_SHIFT);
	if (likely(bo != NULL))
		ttm_bo_reference(bo);
	read_unlock(&bdev->vm_lock);

	if (unlikely(bo == NULL)) {
		printk(KERN_ERR TTM_PFX
		       "Could not find buffer object to map.\n");
		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_RESERVED | VM_IO | VM_MIXEDMAP | VM_DONTEXPAND;
	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_RESERVED | 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;

	read_lock(&bdev->vm_lock);
	bo = ttm_bo_vm_lookup_rb(bdev, dev_offset, 1);
	if (likely(bo != NULL))
		ttm_bo_reference(bo);
	read_unlock(&bdev->vm_lock);

	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 - bo->vm_node->start;
	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
	31	#include <ttm/ttm_module.h>
	32	#include <ttm/ttm_bo_driver.h>
	33	#include <ttm/ttm_placement.h>
	34	#include <linux/mm.h>
ba4e7d97 TH	35	#include <linux/rbtree.h>
	36	#include <linux/module.h>
	37	#include <linux/uaccess.h>
	38
	39	#define TTM_BO_VM_NUM_PREFAULT 16
	40
	41	static struct ttm_buffer_object ttm_bo_vm_lookup_rb(struct ttm_bo_device bdev,
	42	unsigned long page_start,
	43	unsigned long num_pages)
	44	{
	45	struct rb_node *cur = bdev->addr_space_rb.rb_node;
	46	unsigned long cur_offset;
	47	struct ttm_buffer_object *bo;
	48	struct ttm_buffer_object *best_bo = NULL;
	49
	50	while (likely(cur != NULL)) {
	51	bo = rb_entry(cur, struct ttm_buffer_object, vm_rb);
	52	cur_offset = bo->vm_node->start;
	53	if (page_start >= cur_offset) {
	54	cur = cur->rb_right;
	55	best_bo = bo;
	56	if (page_start == cur_offset)
	57	break;
	58	} else
	59	cur = cur->rb_left;
	60	}
	61
	62	if (unlikely(best_bo == NULL))
	63	return NULL;
	64
	65	if (unlikely((best_bo->vm_node->start + best_bo->num_pages) <
	66	(page_start + num_pages)))
	67	return NULL;
	68
	69	return best_bo;
	70	}
	71
	72	static int ttm_bo_vm_fault(struct vm_area_struct vma, struct vm_fault vmf)
	73	{
	74	struct ttm_buffer_object bo = (struct ttm_buffer_object )
	75	vma->vm_private_data;
	76	struct ttm_bo_device *bdev = bo->bdev;
ba4e7d97 TH	77	unsigned long page_offset;
	78	unsigned long page_last;
	79	unsigned long pfn;
	80	struct ttm_tt *ttm = NULL;
	81	struct page *page;
	82	int ret;
	83	int i;
ba4e7d97 TH	84	unsigned long address = (unsigned long)vmf->virtual_address;
ba4e7d97 TH	85	int retval = VM_FAULT_NOPAGE;
eba67093 TH	86	struct ttm_mem_type_manager *man =
eba67093 TH	87	&bdev->man[bo->mem.mem_type];
ba4e7d97 TH	88
	89	/*
	90	* Work around locking order reversal in fault / nopfn
	91	* between mmap_sem and bo_reserve: Perform a trylock operation
	92	* for reserve, and if it fails, retry the fault after scheduling.
	93	*/
	94
	95	ret = ttm_bo_reserve(bo, true, true, false, 0);
	96	if (unlikely(ret != 0)) {
	97	if (ret == -EBUSY)
	98	set_need_resched();
	99	return VM_FAULT_NOPAGE;
	100	}
	101
82c5da6b JG	102	if (bdev->driver->fault_reserve_notify) {
	103	ret = bdev->driver->fault_reserve_notify(bo);
	104	switch (ret) {
	105	case 0:
	106	break;
	107	case -EBUSY:
	108	set_need_resched();
	109	case -ERESTARTSYS:
	110	retval = VM_FAULT_NOPAGE;
	111	goto out_unlock;
	112	default:
	113	retval = VM_FAULT_SIGBUS;
	114	goto out_unlock;
	115	}
	116	}
e024e110	117
ba4e7d97 TH	118	/*
	119	* Wait for buffer data in transit, due to a pipelined
	120	* move.
	121	*/
	122
702adba2	123	spin_lock(&bdev->fence_lock);
ba4e7d97 TH	124	if (test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)) {
ba4e7d97 TH	125	ret = ttm_bo_wait(bo, false, true, false);
702adba2	126	spin_unlock(&bdev->fence_lock);
ba4e7d97	127	if (unlikely(ret != 0)) {
98ffc415	128	retval = (ret != -ERESTARTSYS) ?
ba4e7d97 TH	129	VM_FAULT_SIGBUS : VM_FAULT_NOPAGE;
	130	goto out_unlock;
	131	}
	132	} else
702adba2	133	spin_unlock(&bdev->fence_lock);
ba4e7d97	134
eba67093 TH	135	ret = ttm_mem_io_lock(man, true);
	136	if (unlikely(ret != 0)) {
	137	retval = VM_FAULT_NOPAGE;
ba4e7d97 TH	138	goto out_unlock;
ba4e7d97 TH	139	}
eba67093 TH	140	ret = ttm_mem_io_reserve_vm(bo);
	141	if (unlikely(ret != 0)) {
	142	retval = VM_FAULT_SIGBUS;
	143	goto out_io_unlock;
	144	}
ba4e7d97	145
ba4e7d97 TH	146	page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
	147	bo->vm_node->start - vma->vm_pgoff;
	148	page_last = ((vma->vm_end - vma->vm_start) >> PAGE_SHIFT) +
	149	bo->vm_node->start - vma->vm_pgoff;
	150
	151	if (unlikely(page_offset >= bo->num_pages)) {
	152	retval = VM_FAULT_SIGBUS;
eba67093	153	goto out_io_unlock;
ba4e7d97 TH	154	}
	155
	156	/*
	157	* Strictly, we're not allowed to modify vma->vm_page_prot here,
	158	* since the mmap_sem is only held in read mode. However, we
	159	* modify only the caching bits of vma->vm_page_prot and
	160	* consider those bits protected by
	161	* the bo->mutex, as we should be the only writers.
	162	* There shouldn't really be any readers of these bits except
	163	* within vm_insert_mixed()? fork?
	164	*
	165	* TODO: Add a list of vmas to the bo, and change the
	166	* vma->vm_page_prot when the object changes caching policy, with
	167	* the correct locks held.
	168	*/
82c5da6b	169	if (bo->mem.bus.is_iomem) {
ba4e7d97 TH	170	vma->vm_page_prot = ttm_io_prot(bo->mem.placement,
	171	vma->vm_page_prot);
	172	} else {
	173	ttm = bo->ttm;
	174	vma->vm_page_prot = (bo->mem.placement & TTM_PL_FLAG_CACHED) ?
	175	vm_get_page_prot(vma->vm_flags) :
	176	ttm_io_prot(bo->mem.placement, vma->vm_page_prot);
b1e5f172 JG	177
	178	/* Allocate all page at once, most common usage */
	179	if (ttm->bdev->driver->ttm_tt_populate(ttm)) {
	180	retval = VM_FAULT_OOM;
	181	goto out_io_unlock;
	182	}
ba4e7d97 TH	183	}
	184
	185	/*
	186	* Speculatively prefault a number of pages. Only error on
	187	* first page.
	188	*/
ba4e7d97	189	for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) {
82c5da6b JG	190	if (bo->mem.bus.is_iomem)
82c5da6b JG	191	pfn = ((bo->mem.bus.base + bo->mem.bus.offset) >> PAGE_SHIFT) + page_offset;
ba4e7d97	192	else {
b1e5f172	193	page = ttm->pages[page_offset];
ba4e7d97 TH	194	if (unlikely(!page && i == 0)) {
ba4e7d97 TH	195	retval = VM_FAULT_OOM;
eba67093	196	goto out_io_unlock;
ba4e7d97 TH	197	} else if (unlikely(!page)) {
	198	break;
	199	}
	200	pfn = page_to_pfn(page);
	201	}
	202
	203	ret = vm_insert_mixed(vma, address, pfn);
	204	/*
	205	* Somebody beat us to this PTE or prefaulting to
	206	* an already populated PTE, or prefaulting error.
	207	*/
	208
	209	if (unlikely((ret == -EBUSY) \|\| (ret != 0 && i > 0)))
	210	break;
	211	else if (unlikely(ret != 0)) {
	212	retval =
	213	(ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
eba67093	214	goto out_io_unlock;
ba4e7d97 TH	215	}
	216
	217	address += PAGE_SIZE;
	218	if (unlikely(++page_offset >= page_last))
	219	break;
	220	}
eba67093 TH	221	out_io_unlock:
eba67093 TH	222	ttm_mem_io_unlock(man);
ba4e7d97 TH	223	out_unlock:
	224	ttm_bo_unreserve(bo);
	225	return retval;
	226	}
	227
	228	static void ttm_bo_vm_open(struct vm_area_struct *vma)
	229	{
	230	struct ttm_buffer_object *bo =
	231	(struct ttm_buffer_object *)vma->vm_private_data;
	232
	233	(void)ttm_bo_reference(bo);
	234	}
	235
	236	static void ttm_bo_vm_close(struct vm_area_struct *vma)
	237	{
82c5da6b	238	struct ttm_buffer_object bo = (struct ttm_buffer_object )vma->vm_private_data;
ba4e7d97 TH	239
	240	ttm_bo_unref(&bo);
	241	vma->vm_private_data = NULL;
	242	}
	243
f0f37e2f	244	static const struct vm_operations_struct ttm_bo_vm_ops = {
ba4e7d97 TH	245	.fault = ttm_bo_vm_fault,
	246	.open = ttm_bo_vm_open,
	247	.close = ttm_bo_vm_close
	248	};
	249
	250	int ttm_bo_mmap(struct file filp, struct vm_area_struct vma,
	251	struct ttm_bo_device *bdev)
	252	{
	253	struct ttm_bo_driver *driver;
	254	struct ttm_buffer_object *bo;
	255	int ret;
	256
	257	read_lock(&bdev->vm_lock);
	258	bo = ttm_bo_vm_lookup_rb(bdev, vma->vm_pgoff,
	259	(vma->vm_end - vma->vm_start) >> PAGE_SHIFT);
	260	if (likely(bo != NULL))
	261	ttm_bo_reference(bo);
	262	read_unlock(&bdev->vm_lock);
	263
	264	if (unlikely(bo == NULL)) {
	265	printk(KERN_ERR TTM_PFX
	266	"Could not find buffer object to map.\n");
	267	return -EINVAL;
	268	}
	269
	270	driver = bo->bdev->driver;
	271	if (unlikely(!driver->verify_access)) {
	272	ret = -EPERM;
	273	goto out_unref;
	274	}
	275	ret = driver->verify_access(bo, filp);
	276	if (unlikely(ret != 0))
	277	goto out_unref;
	278
	279	vma->vm_ops = &ttm_bo_vm_ops;
	280
	281	/*
	282	* Note: We're transferring the bo reference to
	283	* vma->vm_private_data here.
	284	*/
	285
	286	vma->vm_private_data = bo;
	287	vma->vm_flags \|= VM_RESERVED \| VM_IO \| VM_MIXEDMAP \| VM_DONTEXPAND;
	288	return 0;
	289	out_unref:
	290	ttm_bo_unref(&bo);
	291	return ret;
	292	}
	293	EXPORT_SYMBOL(ttm_bo_mmap);
	294
	295	int ttm_fbdev_mmap(struct vm_area_struct vma, struct ttm_buffer_object bo)
	296	{
	297	if (vma->vm_pgoff != 0)
	298	return -EACCES;
	299
	300	vma->vm_ops = &ttm_bo_vm_ops;
	301	vma->vm_private_data = ttm_bo_reference(bo);
	302	vma->vm_flags \|= VM_RESERVED \| VM_IO \| VM_MIXEDMAP \| VM_DONTEXPAND;
	303	return 0;
	304	}
	305	EXPORT_SYMBOL(ttm_fbdev_mmap);
	306
	307
	308	ssize_t ttm_bo_io(struct ttm_bo_device bdev, struct file filp,
309	const char __user wbuf, char __user rbuf, size_t count,
310	loff_t *f_pos, bool write)
311	{
312	struct ttm_buffer_object *bo;
313	struct ttm_bo_driver *driver;
314	struct ttm_bo_kmap_obj map;
315	unsigned long dev_offset = (*f_pos >> PAGE_SHIFT);
316	unsigned long kmap_offset;
317	unsigned long kmap_end;
318	unsigned long kmap_num;
319	size_t io_size;
320	unsigned int page_offset;
321	char *virtual;
322	int ret;
323	bool no_wait = false;
324	bool dummy;
325
326	read_lock(&bdev->vm_lock);
327	bo = ttm_bo_vm_lookup_rb(bdev, dev_offset, 1);
328	if (likely(bo != NULL))
329	ttm_bo_reference(bo);
330	read_unlock(&bdev->vm_lock);
331
332	if (unlikely(bo == NULL))
333	return -EFAULT;
334
335	driver = bo->bdev->driver;
b8ff7357	336	if (unlikely(!driver->verify_access)) {
ba4e7d97 TH	337	ret = -EPERM;
	338	goto out_unref;
	339	}
	340
	341	ret = driver->verify_access(bo, filp);
	342	if (unlikely(ret != 0))
	343	goto out_unref;
	344
	345	kmap_offset = dev_offset - bo->vm_node->start;
916635bf	346	if (unlikely(kmap_offset >= bo->num_pages)) {
ba4e7d97 TH	347	ret = -EFBIG;
	348	goto out_unref;
	349	}
	350
	351	page_offset = *f_pos & ~PAGE_MASK;
	352	io_size = bo->num_pages - kmap_offset;
	353	io_size = (io_size << PAGE_SHIFT) - page_offset;
	354	if (count < io_size)
	355	io_size = count;
	356
	357	kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
	358	kmap_num = kmap_end - kmap_offset + 1;
	359
	360	ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
	361
	362	switch (ret) {
	363	case 0:
	364	break;
ba4e7d97 TH	365	case -EBUSY:
	366	ret = -EAGAIN;
	367	goto out_unref;
	368	default:
	369	goto out_unref;
	370	}
	371
	372	ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
	373	if (unlikely(ret != 0)) {
	374	ttm_bo_unreserve(bo);
	375	goto out_unref;
	376	}
	377
	378	virtual = ttm_kmap_obj_virtual(&map, &dummy);
	379	virtual += page_offset;
	380
	381	if (write)
	382	ret = copy_from_user(virtual, wbuf, io_size);
	383	else
	384	ret = copy_to_user(rbuf, virtual, io_size);
	385
	386	ttm_bo_kunmap(&map);
	387	ttm_bo_unreserve(bo);
	388	ttm_bo_unref(&bo);
	389
	390	if (unlikely(ret != 0))
	391	return -EFBIG;
	392
	393	*f_pos += io_size;
	394
	395	return io_size;
	396	out_unref:
	397	ttm_bo_unref(&bo);
	398	return ret;
	399	}
	400
	401	ssize_t ttm_bo_fbdev_io(struct ttm_buffer_object bo, const char __user wbuf,
	402	char __user rbuf, size_t count, loff_t f_pos,
	403	bool write)
	404	{
	405	struct ttm_bo_kmap_obj map;
	406	unsigned long kmap_offset;
	407	unsigned long kmap_end;
	408	unsigned long kmap_num;
	409	size_t io_size;
	410	unsigned int page_offset;
	411	char *virtual;
	412	int ret;
	413	bool no_wait = false;
	414	bool dummy;
	415
	416	kmap_offset = (*f_pos >> PAGE_SHIFT);
916635bf	417	if (unlikely(kmap_offset >= bo->num_pages))
ba4e7d97 TH	418	return -EFBIG;
	419
	420	page_offset = *f_pos & ~PAGE_MASK;
	421	io_size = bo->num_pages - kmap_offset;
	422	io_size = (io_size << PAGE_SHIFT) - page_offset;
	423	if (count < io_size)
	424	io_size = count;
	425
	426	kmap_end = (*f_pos + count - 1) >> PAGE_SHIFT;
	427	kmap_num = kmap_end - kmap_offset + 1;
	428
	429	ret = ttm_bo_reserve(bo, true, no_wait, false, 0);
	430
	431	switch (ret) {
	432	case 0:
	433	break;
ba4e7d97 TH	434	case -EBUSY:
	435	return -EAGAIN;
	436	default:
	437	return ret;
	438	}
	439
	440	ret = ttm_bo_kmap(bo, kmap_offset, kmap_num, &map);
	441	if (unlikely(ret != 0)) {
	442	ttm_bo_unreserve(bo);
	443	return ret;
	444	}
	445
	446	virtual = ttm_kmap_obj_virtual(&map, &dummy);
	447	virtual += page_offset;
	448
	449	if (write)
	450	ret = copy_from_user(virtual, wbuf, io_size);
	451	else
	452	ret = copy_to_user(rbuf, virtual, io_size);
	453
	454	ttm_bo_kunmap(&map);
	455	ttm_bo_unreserve(bo);
	456	ttm_bo_unref(&bo);
	457
	458	if (unlikely(ret != 0))
	459	return ret;
	460
	461	*f_pos += io_size;
	462
	463	return io_size;
	464	}