[GitHub/mt8127/android_kernel_alcatel_ttab.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;
}

#ifdef CONFIG_X86
static inline int ttm_tt_set_page_caching(struct page *p,
					  enum ttm_caching_state c_state)
{
	if (PageHighMem(p))
		return 0;

	switch (c_state) {
	case tt_cached:
		return set_pages_wb(p, 1);
	case tt_wc:
	    return set_memory_wc((unsigned long) page_address(p), 1);
	default:
		return set_pages_uc(p, 1);
	}
}
#else /* CONFIG_X86 */
static inline int ttm_tt_set_page_caching(struct page *p,
					  enum ttm_caching_state c_state)
{
	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, 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,
						      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);
}

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	}
	195
	196	#ifdef CONFIG_X86
	197	static inline int ttm_tt_set_page_caching(struct page *p,
	198	enum ttm_caching_state c_state)
	199	{
	200	if (PageHighMem(p))
	201	return 0;
	202
	203	switch (c_state) {
	204	case tt_cached:
	205	return set_pages_wb(p, 1);
	206	case tt_wc:
	207	return set_memory_wc((unsigned long) page_address(p), 1);
	208	default:
	209	return set_pages_uc(p, 1);
	210	}
211	}
212	#else /* CONFIG_X86 */
213	static inline int ttm_tt_set_page_caching(struct page *p,
214	enum ttm_caching_state c_state)
215	{
216	return 0;
217	}
218	#endif /* CONFIG_X86 */
219
220	/*
221	* Change caching policy for the linear kernel map
222	* for range of pages in a ttm.
223	*/
224
225	static int ttm_tt_set_caching(struct ttm_tt *ttm,
226	enum ttm_caching_state c_state)
227	{
228	int i, j;
229	struct page *cur_page;
230	int ret;
231
232	if (ttm->caching_state == c_state)
233	return 0;
234
235	if (c_state != tt_cached) {
236	ret = ttm_tt_populate(ttm);
237	if (unlikely(ret != 0))
238	return ret;
239	}
240
241	if (ttm->caching_state == tt_cached)
c9c97b8c	242	drm_clflush_pages(ttm->pages, ttm->num_pages);
ba4e7d97 TH	243
	244	for (i = 0; i < ttm->num_pages; ++i) {
	245	cur_page = ttm->pages[i];
	246	if (likely(cur_page != NULL)) {
	247	ret = ttm_tt_set_page_caching(cur_page, c_state);
	248	if (unlikely(ret != 0))
	249	goto out_err;
	250	}
	251	}
	252
	253	ttm->caching_state = c_state;
	254
	255	return 0;
	256
	257	out_err:
	258	for (j = 0; j < i; ++j) {
	259	cur_page = ttm->pages[j];
	260	if (likely(cur_page != NULL)) {
	261	(void)ttm_tt_set_page_caching(cur_page,
	262	ttm->caching_state);
	263	}
	264	}
	265
	266	return ret;
	267	}
	268
	269	int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
	270	{
	271	enum ttm_caching_state state;
	272
	273	if (placement & TTM_PL_FLAG_WC)
	274	state = tt_wc;
	275	else if (placement & TTM_PL_FLAG_UNCACHED)
	276	state = tt_uncached;
	277	else
	278	state = tt_cached;
	279
	280	return ttm_tt_set_caching(ttm, state);
	281	}
	282
	283	static void ttm_tt_free_alloced_pages(struct ttm_tt *ttm)
	284	{
	285	int i;
	286	struct page *cur_page;
	287	struct ttm_backend *be = ttm->be;
	288
	289	if (be)
	290	be->func->clear(be);
	291	(void)ttm_tt_set_caching(ttm, tt_cached);
	292	for (i = 0; i < ttm->num_pages; ++i) {
	293	cur_page = ttm->pages[i];
	294	ttm->pages[i] = NULL;
	295	if (cur_page) {
	296	if (page_count(cur_page) != 1)
	297	printk(KERN_ERR TTM_PFX
	298	"Erroneous page count. "
	299	"Leaking pages.\n");
a987fcaa	300	ttm_mem_global_free_page(ttm->glob->mem_glob,
5fd9cbad	301	cur_page);
ba4e7d97 TH	302	__free_page(cur_page);
	303	}
	304	}
	305	ttm->state = tt_unpopulated;
	306	ttm->first_himem_page = ttm->num_pages;
	307	ttm->last_lomem_page = -1;
	308	}
	309
	310	void ttm_tt_destroy(struct ttm_tt *ttm)
	311	{
	312	struct ttm_backend *be;
	313
	314	if (unlikely(ttm == NULL))
	315	return;
	316
	317	be = ttm->be;
	318	if (likely(be != NULL)) {
	319	be->func->destroy(be);
	320	ttm->be = NULL;
	321	}
	322
	323	if (likely(ttm->pages != NULL)) {
	324	if (ttm->page_flags & TTM_PAGE_FLAG_USER)
	325	ttm_tt_free_user_pages(ttm);
	326	else
	327	ttm_tt_free_alloced_pages(ttm);
	328
	329	ttm_tt_free_page_directory(ttm);
	330	}
	331
	332	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP) &&
	333	ttm->swap_storage)
	334	fput(ttm->swap_storage);
	335
	336	kfree(ttm);
	337	}
	338
	339	int ttm_tt_set_user(struct ttm_tt *ttm,
	340	struct task_struct *tsk,
	341	unsigned long start, unsigned long num_pages)
	342	{
	343	struct mm_struct *mm = tsk->mm;
	344	int ret;
	345	int write = (ttm->page_flags & TTM_PAGE_FLAG_WRITE) != 0;
a987fcaa	346	struct ttm_mem_global *mem_glob = ttm->glob->mem_glob;
ba4e7d97 TH	347
	348	BUG_ON(num_pages != ttm->num_pages);
	349	BUG_ON((ttm->page_flags & TTM_PAGE_FLAG_USER) == 0);
	350
	351	/**
	352	* Account user pages as lowmem pages for now.
	353	*/
	354
	355	ret = ttm_mem_global_alloc(mem_glob, num_pages * PAGE_SIZE,
5fd9cbad	356	false, false);
ba4e7d97 TH	357	if (unlikely(ret != 0))
	358	return ret;
	359
	360	down_read(&mm->mmap_sem);
	361	ret = get_user_pages(tsk, mm, start, num_pages,
	362	write, 0, ttm->pages, NULL);
	363	up_read(&mm->mmap_sem);
	364
	365	if (ret != num_pages && write) {
	366	ttm_tt_free_user_pages(ttm);
5fd9cbad	367	ttm_mem_global_free(mem_glob, num_pages * PAGE_SIZE);
ba4e7d97 TH	368	return -ENOMEM;
	369	}
	370
	371	ttm->tsk = tsk;
	372	ttm->start = start;
	373	ttm->state = tt_unbound;
	374
	375	return 0;
	376	}
	377
	378	struct ttm_tt ttm_tt_create(struct ttm_bo_device bdev, unsigned long size,
	379	uint32_t page_flags, struct page *dummy_read_page)
	380	{
	381	struct ttm_bo_driver *bo_driver = bdev->driver;
	382	struct ttm_tt *ttm;
	383
	384	if (!bo_driver)
	385	return NULL;
	386
	387	ttm = kzalloc(sizeof(*ttm), GFP_KERNEL);
	388	if (!ttm)
	389	return NULL;
	390
a987fcaa	391	ttm->glob = bdev->glob;
ba4e7d97 TH	392	ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
	393	ttm->first_himem_page = ttm->num_pages;
	394	ttm->last_lomem_page = -1;
	395	ttm->caching_state = tt_cached;
	396	ttm->page_flags = page_flags;
	397
	398	ttm->dummy_read_page = dummy_read_page;
	399
	400	ttm_tt_alloc_page_directory(ttm);
	401	if (!ttm->pages) {
	402	ttm_tt_destroy(ttm);
	403	printk(KERN_ERR TTM_PFX "Failed allocating page table\n");
	404	return NULL;
	405	}
	406	ttm->be = bo_driver->create_ttm_backend_entry(bdev);
	407	if (!ttm->be) {
	408	ttm_tt_destroy(ttm);
	409	printk(KERN_ERR TTM_PFX "Failed creating ttm backend entry\n");
	410	return NULL;
	411	}
	412	ttm->state = tt_unpopulated;
	413	return ttm;
	414	}
	415
	416	void ttm_tt_unbind(struct ttm_tt *ttm)
	417	{
	418	int ret;
	419	struct ttm_backend *be = ttm->be;
	420
	421	if (ttm->state == tt_bound) {
	422	ret = be->func->unbind(be);
	423	BUG_ON(ret);
	424	ttm->state = tt_unbound;
	425	}
	426	}
	427
	428	int ttm_tt_bind(struct ttm_tt ttm, struct ttm_mem_reg bo_mem)
	429	{
	430	int ret = 0;
	431	struct ttm_backend *be;
	432
	433	if (!ttm)
	434	return -EINVAL;
	435
	436	if (ttm->state == tt_bound)
	437	return 0;
	438
	439	be = ttm->be;
	440
	441	ret = ttm_tt_populate(ttm);
	442	if (ret)
	443	return ret;
	444
	445	ret = be->func->bind(be, bo_mem);
	446	if (ret) {
	447	printk(KERN_ERR TTM_PFX "Couldn't bind backend.\n");
	448	return ret;
	449	}
	450
	451	ttm->state = tt_bound;
	452
	453	if (ttm->page_flags & TTM_PAGE_FLAG_USER)
	454	ttm->page_flags \|= TTM_PAGE_FLAG_USER_DIRTY;
	455	return 0;
456	}
457	EXPORT_SYMBOL(ttm_tt_bind);
458
459	static int ttm_tt_swapin(struct ttm_tt *ttm)
460	{
461	struct address_space *swap_space;
462	struct file *swap_storage;
463	struct page *from_page;
464	struct page *to_page;
465	void *from_virtual;
466	void *to_virtual;
467	int i;
468	int ret;
469
470	if (ttm->page_flags & TTM_PAGE_FLAG_USER) {
471	ret = ttm_tt_set_user(ttm, ttm->tsk, ttm->start,
472	ttm->num_pages);
473	if (unlikely(ret != 0))
474	return ret;
475
476	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
477	return 0;
478	}
479
480	swap_storage = ttm->swap_storage;
481	BUG_ON(swap_storage == NULL);
482
483	swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
484
485	for (i = 0; i < ttm->num_pages; ++i) {
486	from_page = read_mapping_page(swap_space, i, NULL);
487	if (IS_ERR(from_page))
488	goto out_err;
489	to_page = __ttm_tt_get_page(ttm, i);
490	if (unlikely(to_page == NULL))
491	goto out_err;
492
493	preempt_disable();
494	from_virtual = kmap_atomic(from_page, KM_USER0);
495	to_virtual = kmap_atomic(to_page, KM_USER1);
496	memcpy(to_virtual, from_virtual, PAGE_SIZE);
497	kunmap_atomic(to_virtual, KM_USER1);
498	kunmap_atomic(from_virtual, KM_USER0);
499	preempt_enable();
500	page_cache_release(from_page);
501	}
502
503	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTANT_SWAP))
504	fput(swap_storage);
505	ttm->swap_storage = NULL;
506	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
507
508	return 0;
509	out_err:
510	ttm_tt_free_alloced_pages(ttm);
511	return -ENOMEM;
512	}
513
514	int ttm_tt_swapout(struct ttm_tt ttm, struct file persistant_swap_storage)
515	{
516	struct address_space *swap_space;
517	struct file *swap_storage;
518	struct page *from_page;
519	struct page *to_page;
520	void *from_virtual;
521	void *to_virtual;
522	int i;
523
524	BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
525	BUG_ON(ttm->caching_state != tt_cached);
526
527	/*
528	* For user buffers, just unpin the pages, as there should be
529	* vma references.
530	*/
531
532	if (ttm->page_flags & TTM_PAGE_FLAG_USER) {
533	ttm_tt_free_user_pages(ttm);
534	ttm->page_flags \|= TTM_PAGE_FLAG_SWAPPED;
535	ttm->swap_storage = NULL;
536	return 0;
537	}
538
539	if (!persistant_swap_storage) {
540	swap_storage = shmem_file_setup("ttm swap",
541	ttm->num_pages << PAGE_SHIFT,
542	0);
543	if (unlikely(IS_ERR(swap_storage))) {
544	printk(KERN_ERR "Failed allocating swap storage.\n");
545	return -ENOMEM;
546	}
547	} else
548	swap_storage = persistant_swap_storage;
549
550	swap_space = swap_storage->f_path.dentry->d_inode->i_mapping;
551
552	for (i = 0; i < ttm->num_pages; ++i) {
553	from_page = ttm->pages[i];
554	if (unlikely(from_page == NULL))
555	continue;
556	to_page = read_mapping_page(swap_space, i, NULL);
557	if (unlikely(to_page == NULL))
558	goto out_err;
559
560	preempt_disable();
561	from_virtual = kmap_atomic(from_page, KM_USER0);
562	to_virtual = kmap_atomic(to_page, KM_USER1);
563	memcpy(to_virtual, from_virtual, PAGE_SIZE);
564	kunmap_atomic(to_virtual, KM_USER1);
565	kunmap_atomic(from_virtual, KM_USER0);
566	preempt_enable();
567	set_page_dirty(to_page);
568	mark_page_accessed(to_page);
569	page_cache_release(to_page);
570	}
571
572	ttm_tt_free_alloced_pages(ttm);
573	ttm->swap_storage = swap_storage;
574	ttm->page_flags \|= TTM_PAGE_FLAG_SWAPPED;
575	if (persistant_swap_storage)
576	ttm->page_flags \|= TTM_PAGE_FLAG_PERSISTANT_SWAP;
577
578	return 0;
579	out_err:
580	if (!persistant_swap_storage)
581	fput(swap_storage);
582
583	return -ENOMEM;
584	}