[linux-2.6-block.git] / drivers / gpu / drm / ttm / ttm_tt.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 <linux/vmalloc.h>
#include <linux/sched.h>
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/file.h>
#include <linux/swap.h>
#include "drm_cache.h"
#include "ttm/ttm_module.h"
#include "ttm/ttm_bo_driver.h"
#include "ttm/ttm_placement.h"

static int ttm_tt_swapin(struct ttm_tt *ttm);

/**
 * Allocates storage for pointers to the pages that back the ttm.
 *
 * Uses kmalloc if possible. Otherwise falls back to vmalloc.
 */
static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
{
	unsigned long size = ttm->num_pages * sizeof(*ttm->pages);
	ttm->pages = NULL;

	if (size <= PAGE_SIZE)
		ttm->pages = kzalloc(size, GFP_KERNEL);

	if (!ttm->pages) {
		ttm->pages = vmalloc_user(size);
		if (ttm->pages)
			ttm->page_flags |= TTM_PAGE_FLAG_VMALLOC;
	}
}

static void ttm_tt_free_page_directory(struct ttm_tt *ttm)
{
	if (ttm->page_flags & TTM_PAGE_FLAG_VMALLOC) {
		vfree(ttm->pages);
		ttm->page_flags &= ~TTM_PAGE_FLAG_VMALLOC;
	} else {
		kfree(ttm->pages);
	}
	ttm->pages = NULL;
}

static struct page *ttm_tt_alloc_page(unsigned page_flags)
{
	gfp_t gfp_flags = GFP_USER;

	if (page_flags & TTM_PAGE_FLAG_ZERO_ALLOC)
		gfp_flags |= __GFP_ZERO;

	if (page_flags & TTM_PAGE_FLAG_DMA32)
		gfp_flags |= __GFP_DMA32;
	else
		gfp_flags |= __GFP_HIGHMEM;

	return alloc_page(gfp_flags);
}

static void ttm_tt_free_user_pages(struct ttm_tt *ttm)
{
	int write;
	int dirty;
	struct page *page;
	int i;
	struct ttm_backend *be = ttm->be;

	BUG_ON(!(ttm->page_flags & TTM_PAGE_FLAG_USER));
	write = ((ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0);
	dirty = ((ttm->page_flags & TTM_PAGE_FLAG_USER_DIRTY) != 0);

	if (be)
		be->func->clear(be);

	for (i = 0; i < ttm->num_pages; ++i) {
		page = ttm->pages[i];
		if (page == NULL)
			continue;

		if (page == ttm->dummy_read_page) {
			BUG_ON(write);
			continue;
		}

		if (write && dirty && !PageReserved(page))
			set_page_dirty_lock(page);

		ttm->pages[i] = NULL;
		ttm_mem_global_free(ttm->glob->mem_glob, PAGE_SIZE);
		put_page(page);
	}
	ttm->state = tt_unpopulated;
	ttm->first_himem_page = ttm->num_pages;
	ttm->last_lomem_page = -1;
}

static struct page *__ttm_tt_get_page(struct ttm_tt *ttm, int index)
{
	struct page *p;
	struct ttm_mem_global *mem_glob = ttm->glob->mem_glob;
	int ret;

	while (NULL == (p = ttm->pages[index])) {
		p = ttm_tt_alloc_page(ttm->page_flags);

		if (!p)
			return NULL;

		ret = ttm_mem_global_alloc_page(mem_glob, p, false, false);
		if (unlikely(ret != 0))
			goto out_err;

		if (PageHighMem(p))
			ttm->pages[--ttm->first_himem_page] = p;
		else
			ttm->pages[++ttm->last_lomem_page] = p;
	}
	return p;
out_err:
	put_page(p);
	return NULL;
}

struct page *ttm_tt_get_page(struct ttm_tt *ttm, int index)
{
	int ret;

	if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
		ret = ttm_tt_swapin(ttm);
		if (unlikely(ret != 0))
			return NULL;
	}
	return __ttm_tt_get_page(ttm, index);
}

int ttm_tt_populate(struct ttm_tt *ttm)
{
	struct page *page;
	unsigned long i;
	struct ttm_backend *be;
	int ret;

	if (ttm->state != tt_unpopulated)
		return 0;

	if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
		ret = ttm_tt_swapin(ttm);
		if (unlikely(ret != 0))
			return ret;
	}

	be = ttm->be;

	for (i = 0; i < ttm->num_pages; ++i) {
		page = __ttm_tt_get_page(ttm, i);
		if (!page)
			return -ENOMEM;
	}

	be->func->populate(be, ttm->num_pages, ttm->pages,
			   ttm->dummy_read_page);
	ttm->state = tt_unbound;
	return 0;
}
EXPORT_SYMBOL(ttm_tt_populate);

#ifdef CONFIG_X86
static inline int ttm_tt_set_page_caching(struct page *p,
					  enum ttm_caching_state c_old,
					  enum ttm_caching_state c_new)
{
	int ret = 0;

	if (PageHighMem(p))
		return 0;

	if (c_old != tt_cached) {
		/* p isn't in the default caching state, set it to
		 * writeback first to free its current memtype. */

		ret = set_pages_wb(p, 1);
		if (ret)
			return ret;
	}

	if (c_new == tt_wc)
		ret = set_memory_wc((unsigned long) page_address(p), 1);
	else if (c_new == tt_uncached)
		ret = set_pages_uc(p, 1);

	return ret;
}
#else /* CONFIG_X86 */
static inline int ttm_tt_set_page_caching(struct page *p,
					  enum ttm_caching_state c_old,
					  enum ttm_caching_state c_new)
{
	return 0;
}
#endif /* CONFIG_X86 */

/*
 * Change caching policy for the linear kernel map
 * for range of pages in a ttm.
 */

static int ttm_tt_set_caching(struct ttm_tt *ttm,
			      enum ttm_caching_state c_state)
{
	int i, j;
	struct page *cur_page;
	int ret;

	if (ttm->caching_state == c_state)
		return 0;

	if (c_state != tt_cached) {
		ret = ttm_tt_populate(ttm);
		if (unlikely(ret != 0))
			return ret;
	}

	if (ttm->caching_state == tt_cached)
		drm_clflush_pages(ttm->pages, ttm->num_pages);

	for (i = 0; i < ttm->num_pages; ++i) {
		cur_page = ttm->pages[i];
		if (likely(cur_page != NULL)) {
			ret = ttm_tt_set_page_caching(cur_page,
						      ttm->caching_state,
						      c_state);
			if (unlikely(ret != 0))
				goto out_err;
		}
	}

	ttm->caching_state = c_state;

	return 0;

out_err:
	for (j = 0; j < i; ++j) {
		cur_page = ttm->pages[j];
		if (likely(cur_page != NULL)) {
			(void)ttm_tt_set_page_caching(cur_page, c_state,
						      ttm->caching_state);
		}
	}

	return ret;
}

int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
{
	enum ttm_caching_state state;

	if (placement & TTM_PL_FLAG_WC)
		state = tt_wc;
	else if (placement & TTM_PL_FLAG_UNCACHED)
		state = tt_uncached;
	else
		state = tt_cached;

	return ttm_tt_set_caching(ttm, state);
}
EXPORT_SYMBOL(ttm_tt_set_placement_caching);

static void ttm_tt_free_alloced_pages(struct ttm_tt *ttm)
{
	int i;
	struct page *cur_page;
	struct ttm_backend *be = ttm->be;

	if (be)
		be->func->clear(be);
	(void)ttm_tt_set_caching(ttm, tt_cached);
	for (i = 0; i < ttm->num_pages; ++i) {
		cur_page = ttm->pages[i];
		ttm->pages[i] = NULL;
		if (cur_page) {
			if (page_count(cur_page) != 1)
				printk(KERN_ERR TTM_PFX
				       "Erroneous page count. "
				       "Leaking pages.\n");
			ttm_mem_global_free_page(ttm->glob->mem_glob,
						 cur_page);
			__free_page(cur_page);
		}
	}
	ttm->state = tt_unpopulated;
	ttm->first_himem_page = ttm->num_pages;
	ttm->last_lomem_page = -1;
}

void ttm_tt_destroy(struct ttm_tt *ttm)
{
	struct ttm_backend *be;

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

	be = ttm->be;
	if (likely(be != NULL)) {
		be->func->destroy(be);
		ttm->be = NULL;
	}

	if (likely(ttm->pages != NULL)) {
		if (ttm->page_flags & TTM_PAGE_FLAG_USER)
			ttm_tt_free_user_pages(ttm);
		else
			ttm_tt_free_alloced_pages(ttm);

		ttm_tt_free_page_directory(ttm);
	}

	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP) &&
	    ttm->swap_storage)
		fput(ttm->swap_storage);

	kfree(ttm);
}

int ttm_tt_set_user(struct ttm_tt *ttm,
		    struct task_struct *tsk,
		    unsigned long start, unsigned long num_pages)
{
	struct mm_struct *mm = tsk->mm;
	int ret;
	int write = (ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0;
	struct ttm_mem_global *mem_glob = ttm->glob->mem_glob;

	BUG_ON(num_pages != ttm->num_pages);
	BUG_ON((ttm->page_flags & TTM_PAGE_FLAG_USER) == 0);

	/**
	 * Account user pages as lowmem pages for now.
	 */

	ret = ttm_mem_global_alloc(mem_glob, num_pages * PAGE_SIZE,
				   false, false);
	if (unlikely(ret != 0))
		return ret;

	down_read(&mm->mmap_sem);
	ret = get_user_pages(tsk, mm, start, num_pages,
			     write, 0, ttm->pages, NULL);
	up_read(&mm->mmap_sem);

	if (ret != num_pages && write) {
		ttm_tt_free_user_pages(ttm);
		ttm_mem_global_free(mem_glob, num_pages * PAGE_SIZE);
		return -ENOMEM;
	}

	ttm->tsk = tsk;
	ttm->start = start;
	ttm->state = tt_unbound;

	return 0;
}

struct ttm_tt *ttm_tt_create(struct ttm_bo_device *bdev, unsigned long size,
			     uint32_t page_flags, struct page *dummy_read_page)
{
	struct ttm_bo_driver *bo_driver = bdev->driver;
	struct ttm_tt *ttm;

	if (!bo_driver)
		return NULL;

	ttm = kzalloc(sizeof(*ttm), GFP_KERNEL);
	if (!ttm)
		return NULL;

	ttm->glob = bdev->glob;
	ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
	ttm->first_himem_page = ttm->num_pages;
	ttm->last_lomem_page = -1;
	ttm->caching_state = tt_cached;
	ttm->page_flags = page_flags;

	ttm->dummy_read_page = dummy_read_page;

	ttm_tt_alloc_page_directory(ttm);
	if (!ttm->pages) {
		ttm_tt_destroy(ttm);
		printk(KERN_ERR TTM_PFX "Failed allocating page table\n");
		return NULL;
	}
	ttm->be = bo_driver->create_ttm_backend_entry(bdev);
	if (!ttm->be) {
		ttm_tt_destroy(ttm);
		printk(KERN_ERR TTM_PFX "Failed creating ttm backend entry\n");
		return NULL;
	}
	ttm->state = tt_unpopulated;
	return ttm;
}

void ttm_tt_unbind(struct ttm_tt *ttm)
{
	int ret;
	struct ttm_backend *be = ttm->be;

	if (ttm->state == tt_bound) {
		ret = be->func->unbind(be);
		BUG_ON(ret);
		ttm->state = tt_unbound;
	}
}

int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
{
	int ret = 0;
	struct ttm_backend *be;

	if (!ttm)
		return -EINVAL;

	if (ttm->state == tt_bound)
		return 0;

	be = ttm->be;

	ret = ttm_tt_populate(ttm);
	if (ret)
		return ret;

	ret = be->func->bind(be, bo_mem);
	if (ret) {
		printk(KERN_ERR TTM_PFX "Couldn't bind backend.\n");
		return ret;
	}

	ttm->state = tt_bound;

	if (ttm->page_flags & TTM_PAGE_FLAG_USER)
		ttm->page_flags |= TTM_PAGE_FLAG_USER_DIRTY;
	return 0;
}
EXPORT_SYMBOL(ttm_tt_bind);

static int ttm_tt_swapin(struct ttm_tt *ttm)
{
	struct address_space *swap_space;
	struct file *swap_storage;
	struct page *from_page;
	struct page *to_page;
	void *from_virtual;
	void *to_virtual;
	int i;
	int ret;

	if (ttm->page_flags & TTM_PAGE_FLAG_USER) {
		ret = ttm_tt_set_user(ttm, ttm->tsk, ttm->start,
				      ttm->num_pages);
		if (unlikely(ret != 0))
			return ret;

		ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
		return 0;
	}

	swap_storage = ttm->swap_storage;
	BUG_ON(swap_storage == NULL);

	swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;

	for (i = 0; i < ttm->num_pages; ++i) {
		from_page = read_mapping_page(swap_space, i, NULL);
		if (IS_ERR(from_page))
			goto out_err;
		to_page = __ttm_tt_get_page(ttm, i);
		if (unlikely(to_page == NULL))
			goto out_err;

		preempt_disable();
		from_virtual = kmap_atomic(from_page, KM_USER0);
		to_virtual = kmap_atomic(to_page, KM_USER1);
		memcpy(to_virtual, from_virtual, PAGE_SIZE);
		kunmap_atomic(to_virtual, KM_USER1);
		kunmap_atomic(from_virtual, KM_USER0);
		preempt_enable();
		page_cache_release(from_page);
	}

	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP))
		fput(swap_storage);
	ttm->swap_storage = NULL;
	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;

	return 0;
out_err:
	ttm_tt_free_alloced_pages(ttm);
	return -ENOMEM;
}

int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistant_swap_storage)
{
	struct address_space *swap_space;
	struct file *swap_storage;
	struct page *from_page;
	struct page *to_page;
	void *from_virtual;
	void *to_virtual;
	int i;

	BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
	BUG_ON(ttm->caching_state != tt_cached);

	/*
	 * For user buffers, just unpin the pages, as there should be
	 * vma references.
	 */

	if (ttm->page_flags & TTM_PAGE_FLAG_USER) {
		ttm_tt_free_user_pages(ttm);
		ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
		ttm->swap_storage = NULL;
		return 0;
	}

	if (!persistant_swap_storage) {
		swap_storage = shmem_file_setup("ttm swap",
						ttm->num_pages << PAGE_SHIFT,
						0);
		if (unlikely(IS_ERR(swap_storage))) {
			printk(KERN_ERR "Failed allocating swap storage.\n");
			return -ENOMEM;
		}
	} else
		swap_storage = persistant_swap_storage;

	swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;

	for (i = 0; i < ttm->num_pages; ++i) {
		from_page = ttm->pages[i];
		if (unlikely(from_page == NULL))
			continue;
		to_page = read_mapping_page(swap_space, i, NULL);
		if (unlikely(to_page == NULL))
			goto out_err;

		preempt_disable();
		from_virtual = kmap_atomic(from_page, KM_USER0);
		to_virtual = kmap_atomic(to_page, KM_USER1);
		memcpy(to_virtual, from_virtual, PAGE_SIZE);
		kunmap_atomic(to_virtual, KM_USER1);
		kunmap_atomic(from_virtual, KM_USER0);
		preempt_enable();
		set_page_dirty(to_page);
		mark_page_accessed(to_page);
		page_cache_release(to_page);
	}

	ttm_tt_free_alloced_pages(ttm);
	ttm->swap_storage = swap_storage;
	ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
	if (persistant_swap_storage)
		ttm->page_flags |= TTM_PAGE_FLAG_PERSISTANT_SWAP;

	return 0;
out_err:
	if (!persistant_swap_storage)
		fput(swap_storage);

	return -ENOMEM;
}
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
ba4e7d97 TH	31	#include <linux/vmalloc.h>
	32	#include <linux/sched.h>
	33	#include <linux/highmem.h>
	34	#include <linux/pagemap.h>
	35	#include <linux/file.h>
	36	#include <linux/swap.h>
c9c97b8c	37	#include "drm_cache.h"
ba4e7d97 TH	38	#include "ttm/ttm_module.h"
	39	#include "ttm/ttm_bo_driver.h"
	40	#include "ttm/ttm_placement.h"
	41
	42	static int ttm_tt_swapin(struct ttm_tt *ttm);
	43
ba4e7d97 TH	44	/**
	45	* Allocates storage for pointers to the pages that back the ttm.
	46	*
	47	* Uses kmalloc if possible. Otherwise falls back to vmalloc.
	48	*/
	49	static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
	50	{
	51	unsigned long size = ttm->num_pages * sizeof(*ttm->pages);
	52	ttm->pages = NULL;
	53
	54	if (size <= PAGE_SIZE)
	55	ttm->pages = kzalloc(size, GFP_KERNEL);
	56
	57	if (!ttm->pages) {
	58	ttm->pages = vmalloc_user(size);
	59	if (ttm->pages)
	60	ttm->page_flags \|= TTM_PAGE_FLAG_VMALLOC;
	61	}
	62	}
	63
	64	static void ttm_tt_free_page_directory(struct ttm_tt *ttm)
	65	{
	66	if (ttm->page_flags & TTM_PAGE_FLAG_VMALLOC) {
	67	vfree(ttm->pages);
	68	ttm->page_flags &= ~TTM_PAGE_FLAG_VMALLOC;
	69	} else {
	70	kfree(ttm->pages);
	71	}
	72	ttm->pages = NULL;
	73	}
	74
	75	static struct page *ttm_tt_alloc_page(unsigned page_flags)
	76	{
b42db2b1	77	gfp_t gfp_flags = GFP_USER;
ad49f501	78
ba4e7d97	79	if (page_flags & TTM_PAGE_FLAG_ZERO_ALLOC)
ad49f501 DA	80	gfp_flags \|= __GFP_ZERO;
	81
	82	if (page_flags & TTM_PAGE_FLAG_DMA32)
	83	gfp_flags \|= __GFP_DMA32;
b42db2b1 DA	84	else
b42db2b1 DA	85	gfp_flags \|= __GFP_HIGHMEM;
ba4e7d97	86
ad49f501	87	return alloc_page(gfp_flags);
ba4e7d97 TH	88	}
	89
	90	static void ttm_tt_free_user_pages(struct ttm_tt *ttm)
	91	{
	92	int write;
	93	int dirty;
	94	struct page *page;
	95	int i;
	96	struct ttm_backend *be = ttm->be;
	97
	98	BUG_ON(!(ttm->page_flags & TTM_PAGE_FLAG_USER));
	99	write = ((ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0);
	100	dirty = ((ttm->page_flags & TTM_PAGE_FLAG_USER_DIRTY) != 0);
	101
	102	if (be)
	103	be->func->clear(be);
	104
	105	for (i = 0; i < ttm->num_pages; ++i) {
	106	page = ttm->pages[i];
	107	if (page == NULL)
	108	continue;
	109
	110	if (page == ttm->dummy_read_page) {
	111	BUG_ON(write);
	112	continue;
	113	}
	114
	115	if (write && dirty && !PageReserved(page))
	116	set_page_dirty_lock(page);
	117
	118	ttm->pages[i] = NULL;
a987fcaa	119	ttm_mem_global_free(ttm->glob->mem_glob, PAGE_SIZE);
ba4e7d97 TH	120	put_page(page);
	121	}
	122	ttm->state = tt_unpopulated;
	123	ttm->first_himem_page = ttm->num_pages;
	124	ttm->last_lomem_page = -1;
	125	}
	126
	127	static struct page __ttm_tt_get_page(struct ttm_tt ttm, int index)
	128	{
	129	struct page *p;
a987fcaa	130	struct ttm_mem_global *mem_glob = ttm->glob->mem_glob;
ba4e7d97 TH	131	int ret;
	132
	133	while (NULL == (p = ttm->pages[index])) {
	134	p = ttm_tt_alloc_page(ttm->page_flags);
	135
	136	if (!p)
	137	return NULL;
	138
5fd9cbad TH	139	ret = ttm_mem_global_alloc_page(mem_glob, p, false, false);
	140	if (unlikely(ret != 0))
	141	goto out_err;
	142
	143	if (PageHighMem(p))
ba4e7d97	144	ttm->pages[--ttm->first_himem_page] = p;
5fd9cbad	145	else
ba4e7d97	146	ttm->pages[++ttm->last_lomem_page] = p;
ba4e7d97 TH	147	}
	148	return p;
	149	out_err:
	150	put_page(p);
	151	return NULL;
	152	}
	153
	154	struct page ttm_tt_get_page(struct ttm_tt ttm, int index)
	155	{
	156	int ret;
	157
	158	if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
	159	ret = ttm_tt_swapin(ttm);
	160	if (unlikely(ret != 0))
	161	return NULL;
	162	}
	163	return __ttm_tt_get_page(ttm, index);
	164	}
	165
	166	int ttm_tt_populate(struct ttm_tt *ttm)
	167	{
	168	struct page *page;
	169	unsigned long i;
	170	struct ttm_backend *be;
	171	int ret;
	172
	173	if (ttm->state != tt_unpopulated)
	174	return 0;
	175
	176	if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
	177	ret = ttm_tt_swapin(ttm);
	178	if (unlikely(ret != 0))
	179	return ret;
	180	}
	181
	182	be = ttm->be;
	183
	184	for (i = 0; i < ttm->num_pages; ++i) {
	185	page = __ttm_tt_get_page(ttm, i);
	186	if (!page)
	187	return -ENOMEM;
	188	}
	189
	190	be->func->populate(be, ttm->num_pages, ttm->pages,
	191	ttm->dummy_read_page);
	192	ttm->state = tt_unbound;
	193	return 0;
	194	}
4bfd75cb	195	EXPORT_SYMBOL(ttm_tt_populate);
ba4e7d97 TH	196
	197	#ifdef CONFIG_X86
	198	static inline int ttm_tt_set_page_caching(struct page *p,
f0e2f38b FJ	199	enum ttm_caching_state c_old,
f0e2f38b FJ	200	enum ttm_caching_state c_new)
ba4e7d97	201	{
db78e27d FJ	202	int ret = 0;
db78e27d FJ	203
ba4e7d97 TH	204	if (PageHighMem(p))
	205	return 0;
	206
f0e2f38b	207	if (c_old != tt_cached) {
db78e27d FJ	208	/* p isn't in the default caching state, set it to
	209	* writeback first to free its current memtype. */
	210
	211	ret = set_pages_wb(p, 1);
	212	if (ret)
	213	return ret;
ba4e7d97	214	}
db78e27d	215
f0e2f38b	216	if (c_new == tt_wc)
db78e27d	217	ret = set_memory_wc((unsigned long) page_address(p), 1);
f0e2f38b	218	else if (c_new == tt_uncached)
db78e27d FJ	219	ret = set_pages_uc(p, 1);
	220
	221	return ret;
ba4e7d97 TH	222	}
	223	#else /* CONFIG_X86 */
	224	static inline int ttm_tt_set_page_caching(struct page *p,
f0e2f38b FJ	225	enum ttm_caching_state c_old,
f0e2f38b FJ	226	enum ttm_caching_state c_new)
ba4e7d97 TH	227	{
	228	return 0;
	229	}
	230	#endif /* CONFIG_X86 */
	231
	232	/*
	233	* Change caching policy for the linear kernel map
	234	* for range of pages in a ttm.
	235	*/
	236
	237	static int ttm_tt_set_caching(struct ttm_tt *ttm,
	238	enum ttm_caching_state c_state)
	239	{
	240	int i, j;
	241	struct page *cur_page;
	242	int ret;
	243
	244	if (ttm->caching_state == c_state)
	245	return 0;
	246
	247	if (c_state != tt_cached) {
	248	ret = ttm_tt_populate(ttm);
	249	if (unlikely(ret != 0))
	250	return ret;
	251	}
	252
	253	if (ttm->caching_state == tt_cached)
c9c97b8c	254	drm_clflush_pages(ttm->pages, ttm->num_pages);
ba4e7d97 TH	255
	256	for (i = 0; i < ttm->num_pages; ++i) {
	257	cur_page = ttm->pages[i];
	258	if (likely(cur_page != NULL)) {
f0e2f38b FJ	259	ret = ttm_tt_set_page_caching(cur_page,
	260	ttm->caching_state,
	261	c_state);
ba4e7d97 TH	262	if (unlikely(ret != 0))
	263	goto out_err;
	264	}
	265	}
	266
	267	ttm->caching_state = c_state;
	268
	269	return 0;
	270
	271	out_err:
	272	for (j = 0; j < i; ++j) {
	273	cur_page = ttm->pages[j];
	274	if (likely(cur_page != NULL)) {
f0e2f38b	275	(void)ttm_tt_set_page_caching(cur_page, c_state,
ba4e7d97 TH	276	ttm->caching_state);
	277	}
	278	}
	279
	280	return ret;
	281	}
	282
	283	int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
	284	{
	285	enum ttm_caching_state state;
	286
	287	if (placement & TTM_PL_FLAG_WC)
	288	state = tt_wc;
	289	else if (placement & TTM_PL_FLAG_UNCACHED)
	290	state = tt_uncached;
	291	else
	292	state = tt_cached;
	293
	294	return ttm_tt_set_caching(ttm, state);
	295	}
df67bed9	296	EXPORT_SYMBOL(ttm_tt_set_placement_caching);
ba4e7d97 TH	297
	298	static void ttm_tt_free_alloced_pages(struct ttm_tt *ttm)
	299	{
	300	int i;
	301	struct page *cur_page;
	302	struct ttm_backend *be = ttm->be;
	303
	304	if (be)
	305	be->func->clear(be);
	306	(void)ttm_tt_set_caching(ttm, tt_cached);
	307	for (i = 0; i < ttm->num_pages; ++i) {
	308	cur_page = ttm->pages[i];
	309	ttm->pages[i] = NULL;
	310	if (cur_page) {
	311	if (page_count(cur_page) != 1)
	312	printk(KERN_ERR TTM_PFX
	313	"Erroneous page count. "
	314	"Leaking pages.\n");
a987fcaa	315	ttm_mem_global_free_page(ttm->glob->mem_glob,
5fd9cbad	316	cur_page);
ba4e7d97 TH	317	__free_page(cur_page);
	318	}
	319	}
	320	ttm->state = tt_unpopulated;
	321	ttm->first_himem_page = ttm->num_pages;
	322	ttm->last_lomem_page = -1;
	323	}
	324
	325	void ttm_tt_destroy(struct ttm_tt *ttm)
	326	{
	327	struct ttm_backend *be;
	328
	329	if (unlikely(ttm == NULL))
	330	return;
	331
	332	be = ttm->be;
	333	if (likely(be != NULL)) {
	334	be->func->destroy(be);
	335	ttm->be = NULL;
	336	}
	337
	338	if (likely(ttm->pages != NULL)) {
	339	if (ttm->page_flags & TTM_PAGE_FLAG_USER)
	340	ttm_tt_free_user_pages(ttm);
	341	else
	342	ttm_tt_free_alloced_pages(ttm);
	343
	344	ttm_tt_free_page_directory(ttm);
	345	}
	346
	347	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP) &&
	348	ttm->swap_storage)
	349	fput(ttm->swap_storage);
	350
	351	kfree(ttm);
	352	}
	353
	354	int ttm_tt_set_user(struct ttm_tt *ttm,
	355	struct task_struct *tsk,
	356	unsigned long start, unsigned long num_pages)
	357	{
	358	struct mm_struct *mm = tsk->mm;
	359	int ret;
	360	int write = (ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0;
a987fcaa	361	struct ttm_mem_global *mem_glob = ttm->glob->mem_glob;
ba4e7d97 TH	362
	363	BUG_ON(num_pages != ttm->num_pages);
	364	BUG_ON((ttm->page_flags & TTM_PAGE_FLAG_USER) == 0);
	365
	366	/**
	367	* Account user pages as lowmem pages for now.
	368	*/
	369
	370	ret = ttm_mem_global_alloc(mem_glob, num_pages * PAGE_SIZE,
5fd9cbad	371	false, false);
ba4e7d97 TH	372	if (unlikely(ret != 0))
	373	return ret;
	374
	375	down_read(&mm->mmap_sem);
	376	ret = get_user_pages(tsk, mm, start, num_pages,
	377	write, 0, ttm->pages, NULL);
	378	up_read(&mm->mmap_sem);
	379
	380	if (ret != num_pages && write) {
	381	ttm_tt_free_user_pages(ttm);
5fd9cbad	382	ttm_mem_global_free(mem_glob, num_pages * PAGE_SIZE);
ba4e7d97 TH	383	return -ENOMEM;
	384	}
	385
	386	ttm->tsk = tsk;
	387	ttm->start = start;
	388	ttm->state = tt_unbound;
	389
	390	return 0;
	391	}
	392
	393	struct ttm_tt ttm_tt_create(struct ttm_bo_device bdev, unsigned long size,
	394	uint32_t page_flags, struct page *dummy_read_page)
	395	{
	396	struct ttm_bo_driver *bo_driver = bdev->driver;
	397	struct ttm_tt *ttm;
	398
	399	if (!bo_driver)
	400	return NULL;
	401
	402	ttm = kzalloc(sizeof(*ttm), GFP_KERNEL);
	403	if (!ttm)
	404	return NULL;
	405
a987fcaa	406	ttm->glob = bdev->glob;
ba4e7d97 TH	407	ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
	408	ttm->first_himem_page = ttm->num_pages;
	409	ttm->last_lomem_page = -1;
	410	ttm->caching_state = tt_cached;
	411	ttm->page_flags = page_flags;
	412
	413	ttm->dummy_read_page = dummy_read_page;
	414
	415	ttm_tt_alloc_page_directory(ttm);
	416	if (!ttm->pages) {
	417	ttm_tt_destroy(ttm);
	418	printk(KERN_ERR TTM_PFX "Failed allocating page table\n");
	419	return NULL;
	420	}
	421	ttm->be = bo_driver->create_ttm_backend_entry(bdev);
	422	if (!ttm->be) {
	423	ttm_tt_destroy(ttm);
	424	printk(KERN_ERR TTM_PFX "Failed creating ttm backend entry\n");
	425	return NULL;
	426	}
	427	ttm->state = tt_unpopulated;
	428	return ttm;
	429	}
	430
	431	void ttm_tt_unbind(struct ttm_tt *ttm)
	432	{
	433	int ret;
	434	struct ttm_backend *be = ttm->be;
	435
	436	if (ttm->state == tt_bound) {
	437	ret = be->func->unbind(be);
	438	BUG_ON(ret);
	439	ttm->state = tt_unbound;
	440	}
	441	}
	442
	443	int ttm_tt_bind(struct ttm_tt ttm, struct ttm_mem_reg bo_mem)
	444	{
	445	int ret = 0;
	446	struct ttm_backend *be;
	447
	448	if (!ttm)
	449	return -EINVAL;
	450
	451	if (ttm->state == tt_bound)
	452	return 0;
	453
	454	be = ttm->be;
	455
	456	ret = ttm_tt_populate(ttm);
	457	if (ret)
	458	return ret;
	459
	460	ret = be->func->bind(be, bo_mem);
	461	if (ret) {
	462	printk(KERN_ERR TTM_PFX "Couldn't bind backend.\n");
	463	return ret;
	464	}
	465
	466	ttm->state = tt_bound;
	467
	468	if (ttm->page_flags & TTM_PAGE_FLAG_USER)
	469	ttm->page_flags \|= TTM_PAGE_FLAG_USER_DIRTY;
	470	return 0;
471	}
472	EXPORT_SYMBOL(ttm_tt_bind);
473
474	static int ttm_tt_swapin(struct ttm_tt *ttm)
475	{
476	struct address_space *swap_space;
477	struct file *swap_storage;
478	struct page *from_page;
479	struct page *to_page;
480	void *from_virtual;
481	void *to_virtual;
482	int i;
483	int ret;
484
485	if (ttm->page_flags & TTM_PAGE_FLAG_USER) {
486	ret = ttm_tt_set_user(ttm, ttm->tsk, ttm->start,
487	ttm->num_pages);
488	if (unlikely(ret != 0))
489	return ret;
490
491	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
492	return 0;
493	}
494
495	swap_storage = ttm->swap_storage;
496	BUG_ON(swap_storage == NULL);
497
498	swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
499
500	for (i = 0; i < ttm->num_pages; ++i) {
501	from_page = read_mapping_page(swap_space, i, NULL);
502	if (IS_ERR(from_page))
503	goto out_err;
504	to_page = __ttm_tt_get_page(ttm, i);
505	if (unlikely(to_page == NULL))
506	goto out_err;
507
508	preempt_disable();
509	from_virtual = kmap_atomic(from_page, KM_USER0);
510	to_virtual = kmap_atomic(to_page, KM_USER1);
511	memcpy(to_virtual, from_virtual, PAGE_SIZE);
512	kunmap_atomic(to_virtual, KM_USER1);
513	kunmap_atomic(from_virtual, KM_USER0);
514	preempt_enable();
515	page_cache_release(from_page);
516	}
517
518	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP))
519	fput(swap_storage);
520	ttm->swap_storage = NULL;
521	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
522
523	return 0;
524	out_err:
525	ttm_tt_free_alloced_pages(ttm);
526	return -ENOMEM;
527	}
528
529	int ttm_tt_swapout(struct ttm_tt ttm, struct file persistant_swap_storage)
530	{
531	struct address_space *swap_space;
532	struct file *swap_storage;
533	struct page *from_page;
534	struct page *to_page;
535	void *from_virtual;
536	void *to_virtual;
537	int i;
538
539	BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
540	BUG_ON(ttm->caching_state != tt_cached);
541
542	/*
543	* For user buffers, just unpin the pages, as there should be
544	* vma references.
545	*/
546
547	if (ttm->page_flags & TTM_PAGE_FLAG_USER) {
548	ttm_tt_free_user_pages(ttm);
549	ttm->page_flags \|= TTM_PAGE_FLAG_SWAPPED;
550	ttm->swap_storage = NULL;
551	return 0;
552	}
553
554	if (!persistant_swap_storage) {
555	swap_storage = shmem_file_setup("ttm swap",
556	ttm->num_pages << PAGE_SHIFT,
557	0);
558	if (unlikely(IS_ERR(swap_storage))) {
559	printk(KERN_ERR "Failed allocating swap storage.\n");
560	return -ENOMEM;
561	}
562	} else
563	swap_storage = persistant_swap_storage;
564
565	swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
566
567	for (i = 0; i < ttm->num_pages; ++i) {
568	from_page = ttm->pages[i];
569	if (unlikely(from_page == NULL))
570	continue;
571	to_page = read_mapping_page(swap_space, i, NULL);
572	if (unlikely(to_page == NULL))
573	goto out_err;
574
575	preempt_disable();
576	from_virtual = kmap_atomic(from_page, KM_USER0);
577	to_virtual = kmap_atomic(to_page, KM_USER1);
578	memcpy(to_virtual, from_virtual, PAGE_SIZE);
579	kunmap_atomic(to_virtual, KM_USER1);
580	kunmap_atomic(from_virtual, KM_USER0);
581	preempt_enable();
582	set_page_dirty(to_page);
583	mark_page_accessed(to_page);
584	page_cache_release(to_page);
585	}
586
587	ttm_tt_free_alloced_pages(ttm);
588	ttm->swap_storage = swap_storage;
589	ttm->page_flags \|= TTM_PAGE_FLAG_SWAPPED;
590	if (persistant_swap_storage)
591	ttm->page_flags \|= TTM_PAGE_FLAG_PERSISTANT_SWAP;
592
593	return 0;
594	out_err:
595	if (!persistant_swap_storage)
596	fput(swap_storage);
597
598	return -ENOMEM;
599	}