[linux-2.6-block.git] / drivers / gpu / drm / ttm / ttm_memory.c

/* SPDX-License-Identifier: GPL-2.0 OR MIT */
/**************************************************************************
 *
 * 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.
 *
 **************************************************************************/

#define pr_fmt(fmt) "[TTM] " fmt

#include <drm/ttm/ttm_memory.h>
#include <drm/ttm/ttm_module.h>
#include <drm/ttm/ttm_page_alloc.h>
#include <linux/spinlock.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/swap.h>

#define TTM_MEMORY_ALLOC_RETRIES 4

struct ttm_mem_global ttm_mem_glob;
EXPORT_SYMBOL(ttm_mem_glob);

struct ttm_mem_zone {
	struct kobject kobj;
	struct ttm_mem_global *glob;
	const char *name;
	uint64_t zone_mem;
	uint64_t emer_mem;
	uint64_t max_mem;
	uint64_t swap_limit;
	uint64_t used_mem;
};

static struct attribute ttm_mem_sys = {
	.name = "zone_memory",
	.mode = S_IRUGO
};
static struct attribute ttm_mem_emer = {
	.name = "emergency_memory",
	.mode = S_IRUGO | S_IWUSR
};
static struct attribute ttm_mem_max = {
	.name = "available_memory",
	.mode = S_IRUGO | S_IWUSR
};
static struct attribute ttm_mem_swap = {
	.name = "swap_limit",
	.mode = S_IRUGO | S_IWUSR
};
static struct attribute ttm_mem_used = {
	.name = "used_memory",
	.mode = S_IRUGO
};

static void ttm_mem_zone_kobj_release(struct kobject *kobj)
{
	struct ttm_mem_zone *zone =
		container_of(kobj, struct ttm_mem_zone, kobj);

	pr_info("Zone %7s: Used memory at exit: %llu kiB\n",
		zone->name, (unsigned long long)zone->used_mem >> 10);
	kfree(zone);
}

static ssize_t ttm_mem_zone_show(struct kobject *kobj,
				 struct attribute *attr,
				 char *buffer)
{
	struct ttm_mem_zone *zone =
		container_of(kobj, struct ttm_mem_zone, kobj);
	uint64_t val = 0;

	spin_lock(&zone->glob->lock);
	if (attr == &ttm_mem_sys)
		val = zone->zone_mem;
	else if (attr == &ttm_mem_emer)
		val = zone->emer_mem;
	else if (attr == &ttm_mem_max)
		val = zone->max_mem;
	else if (attr == &ttm_mem_swap)
		val = zone->swap_limit;
	else if (attr == &ttm_mem_used)
		val = zone->used_mem;
	spin_unlock(&zone->glob->lock);

	return snprintf(buffer, PAGE_SIZE, "%llu\n",
			(unsigned long long) val >> 10);
}

static void ttm_check_swapping(struct ttm_mem_global *glob);

static ssize_t ttm_mem_zone_store(struct kobject *kobj,
				  struct attribute *attr,
				  const char *buffer,
				  size_t size)
{
	struct ttm_mem_zone *zone =
		container_of(kobj, struct ttm_mem_zone, kobj);
	int chars;
	unsigned long val;
	uint64_t val64;

	chars = sscanf(buffer, "%lu", &val);
	if (chars == 0)
		return size;

	val64 = val;
	val64 <<= 10;

	spin_lock(&zone->glob->lock);
	if (val64 > zone->zone_mem)
		val64 = zone->zone_mem;
	if (attr == &ttm_mem_emer) {
		zone->emer_mem = val64;
		if (zone->max_mem > val64)
			zone->max_mem = val64;
	} else if (attr == &ttm_mem_max) {
		zone->max_mem = val64;
		if (zone->emer_mem < val64)
			zone->emer_mem = val64;
	} else if (attr == &ttm_mem_swap)
		zone->swap_limit = val64;
	spin_unlock(&zone->glob->lock);

	ttm_check_swapping(zone->glob);

	return size;
}

static struct attribute *ttm_mem_zone_attrs[] = {
	&ttm_mem_sys,
	&ttm_mem_emer,
	&ttm_mem_max,
	&ttm_mem_swap,
	&ttm_mem_used,
	NULL
};

static const struct sysfs_ops ttm_mem_zone_ops = {
	.show = &ttm_mem_zone_show,
	.store = &ttm_mem_zone_store
};

static struct kobj_type ttm_mem_zone_kobj_type = {
	.release = &ttm_mem_zone_kobj_release,
	.sysfs_ops = &ttm_mem_zone_ops,
	.default_attrs = ttm_mem_zone_attrs,
};

static struct attribute ttm_mem_global_lower_mem_limit = {
	.name = "lower_mem_limit",
	.mode = S_IRUGO | S_IWUSR
};

static ssize_t ttm_mem_global_show(struct kobject *kobj,
				 struct attribute *attr,
				 char *buffer)
{
	struct ttm_mem_global *glob =
		container_of(kobj, struct ttm_mem_global, kobj);
	uint64_t val = 0;

	spin_lock(&glob->lock);
	val = glob->lower_mem_limit;
	spin_unlock(&glob->lock);
	/* convert from number of pages to KB */
	val <<= (PAGE_SHIFT - 10);
	return snprintf(buffer, PAGE_SIZE, "%llu\n",
			(unsigned long long) val);
}

static ssize_t ttm_mem_global_store(struct kobject *kobj,
				  struct attribute *attr,
				  const char *buffer,
				  size_t size)
{
	int chars;
	uint64_t val64;
	unsigned long val;
	struct ttm_mem_global *glob =
		container_of(kobj, struct ttm_mem_global, kobj);

	chars = sscanf(buffer, "%lu", &val);
	if (chars == 0)
		return size;

	val64 = val;
	/* convert from KB to number of pages */
	val64 >>= (PAGE_SHIFT - 10);

	spin_lock(&glob->lock);
	glob->lower_mem_limit = val64;
	spin_unlock(&glob->lock);

	return size;
}

static struct attribute *ttm_mem_global_attrs[] = {
	&ttm_mem_global_lower_mem_limit,
	NULL
};

static const struct sysfs_ops ttm_mem_global_ops = {
	.show = &ttm_mem_global_show,
	.store = &ttm_mem_global_store,
};

static struct kobj_type ttm_mem_glob_kobj_type = {
	.sysfs_ops = &ttm_mem_global_ops,
	.default_attrs = ttm_mem_global_attrs,
};

static bool ttm_zones_above_swap_target(struct ttm_mem_global *glob,
					bool from_wq, uint64_t extra)
{
	unsigned int i;
	struct ttm_mem_zone *zone;
	uint64_t target;

	for (i = 0; i < glob->num_zones; ++i) {
		zone = glob->zones[i];

		if (from_wq)
			target = zone->swap_limit;
		else if (capable(CAP_SYS_ADMIN))
			target = zone->emer_mem;
		else
			target = zone->max_mem;

		target = (extra > target) ? 0ULL : target;

		if (zone->used_mem > target)
			return true;
	}
	return false;
}

/**
 * At this point we only support a single shrink callback.
 * Extend this if needed, perhaps using a linked list of callbacks.
 * Note that this function is reentrant:
 * many threads may try to swap out at any given time.
 */

static void ttm_shrink(struct ttm_mem_global *glob, bool from_wq,
			uint64_t extra, struct ttm_operation_ctx *ctx)
{
	int ret;

	spin_lock(&glob->lock);

	while (ttm_zones_above_swap_target(glob, from_wq, extra)) {
		spin_unlock(&glob->lock);
		ret = ttm_bo_swapout(glob->bo_glob, ctx);
		spin_lock(&glob->lock);
		if (unlikely(ret != 0))
			break;
	}

	spin_unlock(&glob->lock);
}

static void ttm_shrink_work(struct work_struct *work)
{
	struct ttm_operation_ctx ctx = {
		.interruptible = false,
		.no_wait_gpu = false
	};
	struct ttm_mem_global *glob =
	    container_of(work, struct ttm_mem_global, work);

	ttm_shrink(glob, true, 0ULL, &ctx);
}

static int ttm_mem_init_kernel_zone(struct ttm_mem_global *glob,
				    const struct sysinfo *si)
{
	struct ttm_mem_zone *zone = kzalloc(sizeof(*zone), GFP_KERNEL);
	uint64_t mem;
	int ret;

	if (unlikely(!zone))
		return -ENOMEM;

	mem = si->totalram - si->totalhigh;
	mem *= si->mem_unit;

	zone->name = "kernel";
	zone->zone_mem = mem;
	zone->max_mem = mem >> 1;
	zone->emer_mem = (mem >> 1) + (mem >> 2);
	zone->swap_limit = zone->max_mem - (mem >> 3);
	zone->used_mem = 0;
	zone->glob = glob;
	glob->zone_kernel = zone;
	ret = kobject_init_and_add(
		&zone->kobj, &ttm_mem_zone_kobj_type, &glob->kobj, zone->name);
	if (unlikely(ret != 0)) {
		kobject_put(&zone->kobj);
		return ret;
	}
	glob->zones[glob->num_zones++] = zone;
	return 0;
}

#ifdef CONFIG_HIGHMEM
static int ttm_mem_init_highmem_zone(struct ttm_mem_global *glob,
				     const struct sysinfo *si)
{
	struct ttm_mem_zone *zone;
	uint64_t mem;
	int ret;

	if (si->totalhigh == 0)
		return 0;

	zone = kzalloc(sizeof(*zone), GFP_KERNEL);
	if (unlikely(!zone))
		return -ENOMEM;

	mem = si->totalram;
	mem *= si->mem_unit;

	zone->name = "highmem";
	zone->zone_mem = mem;
	zone->max_mem = mem >> 1;
	zone->emer_mem = (mem >> 1) + (mem >> 2);
	zone->swap_limit = zone->max_mem - (mem >> 3);
	zone->used_mem = 0;
	zone->glob = glob;
	glob->zone_highmem = zone;
	ret = kobject_init_and_add(
		&zone->kobj, &ttm_mem_zone_kobj_type, &glob->kobj, "%s",
		zone->name);
	if (unlikely(ret != 0)) {
		kobject_put(&zone->kobj);
		return ret;
	}
	glob->zones[glob->num_zones++] = zone;
	return 0;
}
#else
static int ttm_mem_init_dma32_zone(struct ttm_mem_global *glob,
				   const struct sysinfo *si)
{
	struct ttm_mem_zone *zone = kzalloc(sizeof(*zone), GFP_KERNEL);
	uint64_t mem;
	int ret;

	if (unlikely(!zone))
		return -ENOMEM;

	mem = si->totalram;
	mem *= si->mem_unit;

	/**
	 * No special dma32 zone needed.
	 */

	if (mem <= ((uint64_t) 1ULL << 32)) {
		kfree(zone);
		return 0;
	}

	/*
	 * Limit max dma32 memory to 4GB for now
	 * until we can figure out how big this
	 * zone really is.
	 */

	mem = ((uint64_t) 1ULL << 32);
	zone->name = "dma32";
	zone->zone_mem = mem;
	zone->max_mem = mem >> 1;
	zone->emer_mem = (mem >> 1) + (mem >> 2);
	zone->swap_limit = zone->max_mem - (mem >> 3);
	zone->used_mem = 0;
	zone->glob = glob;
	glob->zone_dma32 = zone;
	ret = kobject_init_and_add(
		&zone->kobj, &ttm_mem_zone_kobj_type, &glob->kobj, zone->name);
	if (unlikely(ret != 0)) {
		kobject_put(&zone->kobj);
		return ret;
	}
	glob->zones[glob->num_zones++] = zone;
	return 0;
}
#endif

int ttm_mem_global_init(struct ttm_mem_global *glob)
{
	struct sysinfo si;
	int ret;
	int i;
	struct ttm_mem_zone *zone;

	spin_lock_init(&glob->lock);
	glob->swap_queue = create_singlethread_workqueue("ttm_swap");
	INIT_WORK(&glob->work, ttm_shrink_work);
	ret = kobject_init_and_add(
		&glob->kobj, &ttm_mem_glob_kobj_type, ttm_get_kobj(), "memory_accounting");
	if (unlikely(ret != 0)) {
		kobject_put(&glob->kobj);
		return ret;
	}

	si_meminfo(&si);

	/* set it as 0 by default to keep original behavior of OOM */
	glob->lower_mem_limit = 0;

	ret = ttm_mem_init_kernel_zone(glob, &si);
	if (unlikely(ret != 0))
		goto out_no_zone;
#ifdef CONFIG_HIGHMEM
	ret = ttm_mem_init_highmem_zone(glob, &si);
	if (unlikely(ret != 0))
		goto out_no_zone;
#else
	ret = ttm_mem_init_dma32_zone(glob, &si);
	if (unlikely(ret != 0))
		goto out_no_zone;
#endif
	for (i = 0; i < glob->num_zones; ++i) {
		zone = glob->zones[i];
		pr_info("Zone %7s: Available graphics memory: %llu kiB\n",
			zone->name, (unsigned long long)zone->max_mem >> 10);
	}
	ttm_page_alloc_init(glob, glob->zone_kernel->max_mem/(2*PAGE_SIZE));
	ttm_dma_page_alloc_init(glob, glob->zone_kernel->max_mem/(2*PAGE_SIZE));
	return 0;
out_no_zone:
	ttm_mem_global_release(glob);
	return ret;
}

void ttm_mem_global_release(struct ttm_mem_global *glob)
{
	unsigned int i;
	struct ttm_mem_zone *zone;

	/* let the page allocator first stop the shrink work. */
	ttm_page_alloc_fini();
	ttm_dma_page_alloc_fini();

	flush_workqueue(glob->swap_queue);
	destroy_workqueue(glob->swap_queue);
	glob->swap_queue = NULL;
	for (i = 0; i < glob->num_zones; ++i) {
		zone = glob->zones[i];
		kobject_del(&zone->kobj);
		kobject_put(&zone->kobj);
			}
	kobject_del(&glob->kobj);
	kobject_put(&glob->kobj);
}

static void ttm_check_swapping(struct ttm_mem_global *glob)
{
	bool needs_swapping = false;
	unsigned int i;
	struct ttm_mem_zone *zone;

	spin_lock(&glob->lock);
	for (i = 0; i < glob->num_zones; ++i) {
		zone = glob->zones[i];
		if (zone->used_mem > zone->swap_limit) {
			needs_swapping = true;
			break;
		}
	}

	spin_unlock(&glob->lock);

	if (unlikely(needs_swapping))
		(void)queue_work(glob->swap_queue, &glob->work);

}

static void ttm_mem_global_free_zone(struct ttm_mem_global *glob,
				     struct ttm_mem_zone *single_zone,
				     uint64_t amount)
{
	unsigned int i;
	struct ttm_mem_zone *zone;

	spin_lock(&glob->lock);
	for (i = 0; i < glob->num_zones; ++i) {
		zone = glob->zones[i];
		if (single_zone && zone != single_zone)
			continue;
		zone->used_mem -= amount;
	}
	spin_unlock(&glob->lock);
}

void ttm_mem_global_free(struct ttm_mem_global *glob,
			 uint64_t amount)
{
	return ttm_mem_global_free_zone(glob, NULL, amount);
}
EXPORT_SYMBOL(ttm_mem_global_free);

/*
 * check if the available mem is under lower memory limit
 *
 * a. if no swap disk at all or free swap space is under swap_mem_limit
 * but available system mem is bigger than sys_mem_limit, allow TTM
 * allocation;
 *
 * b. if the available system mem is less than sys_mem_limit but free
 * swap disk is bigger than swap_mem_limit, allow TTM allocation.
 */
bool
ttm_check_under_lowerlimit(struct ttm_mem_global *glob,
			uint64_t num_pages,
			struct ttm_operation_ctx *ctx)
{
	int64_t available;

	if (ctx->flags & TTM_OPT_FLAG_FORCE_ALLOC)
		return false;

	available = get_nr_swap_pages() + si_mem_available();
	available -= num_pages;
	if (available < glob->lower_mem_limit)
		return true;

	return false;
}
EXPORT_SYMBOL(ttm_check_under_lowerlimit);

static int ttm_mem_global_reserve(struct ttm_mem_global *glob,
				  struct ttm_mem_zone *single_zone,
				  uint64_t amount, bool reserve)
{
	uint64_t limit;
	int ret = -ENOMEM;
	unsigned int i;
	struct ttm_mem_zone *zone;

	spin_lock(&glob->lock);
	for (i = 0; i < glob->num_zones; ++i) {
		zone = glob->zones[i];
		if (single_zone && zone != single_zone)
			continue;

		limit = (capable(CAP_SYS_ADMIN)) ?
			zone->emer_mem : zone->max_mem;

		if (zone->used_mem > limit)
			goto out_unlock;
	}

	if (reserve) {
		for (i = 0; i < glob->num_zones; ++i) {
			zone = glob->zones[i];
			if (single_zone && zone != single_zone)
				continue;
			zone->used_mem += amount;
		}
	}

	ret = 0;
out_unlock:
	spin_unlock(&glob->lock);
	ttm_check_swapping(glob);

	return ret;
}


static int ttm_mem_global_alloc_zone(struct ttm_mem_global *glob,
				     struct ttm_mem_zone *single_zone,
				     uint64_t memory,
				     struct ttm_operation_ctx *ctx)
{
	int count = TTM_MEMORY_ALLOC_RETRIES;

	while (unlikely(ttm_mem_global_reserve(glob,
					       single_zone,
					       memory, true)
			!= 0)) {
		if (ctx->no_wait_gpu)
			return -ENOMEM;
		if (unlikely(count-- == 0))
			return -ENOMEM;
		ttm_shrink(glob, false, memory + (memory >> 2) + 16, ctx);
	}

	return 0;
}

int ttm_mem_global_alloc(struct ttm_mem_global *glob, uint64_t memory,
			 struct ttm_operation_ctx *ctx)
{
	/**
	 * Normal allocations of kernel memory are registered in
	 * all zones.
	 */

	return ttm_mem_global_alloc_zone(glob, NULL, memory, ctx);
}
EXPORT_SYMBOL(ttm_mem_global_alloc);

int ttm_mem_global_alloc_page(struct ttm_mem_global *glob,
			      struct page *page, uint64_t size,
			      struct ttm_operation_ctx *ctx)
{
	struct ttm_mem_zone *zone = NULL;

	/**
	 * Page allocations may be registed in a single zone
	 * only if highmem or !dma32.
	 */

#ifdef CONFIG_HIGHMEM
	if (PageHighMem(page) && glob->zone_highmem != NULL)
		zone = glob->zone_highmem;
#else
	if (glob->zone_dma32 && page_to_pfn(page) > 0x00100000UL)
		zone = glob->zone_kernel;
#endif
	return ttm_mem_global_alloc_zone(glob, zone, size, ctx);
}

void ttm_mem_global_free_page(struct ttm_mem_global *glob, struct page *page,
			      uint64_t size)
{
	struct ttm_mem_zone *zone = NULL;

#ifdef CONFIG_HIGHMEM
	if (PageHighMem(page) && glob->zone_highmem != NULL)
		zone = glob->zone_highmem;
#else
	if (glob->zone_dma32 && page_to_pfn(page) > 0x00100000UL)
		zone = glob->zone_kernel;
#endif
	ttm_mem_global_free_zone(glob, zone, size);
}

size_t ttm_round_pot(size_t size)
{
	if ((size & (size - 1)) == 0)
		return size;
	else if (size > PAGE_SIZE)
		return PAGE_ALIGN(size);
	else {
		size_t tmp_size = 4;

		while (tmp_size < size)
			tmp_size <<= 1;

		return tmp_size;
	}
	return 0;
}
EXPORT_SYMBOL(ttm_round_pot);

uint64_t ttm_get_kernel_zone_memory_size(struct ttm_mem_global *glob)
{
	return glob->zone_kernel->max_mem;
}
EXPORT_SYMBOL(ttm_get_kernel_zone_memory_size);
Commit	Line	Data
1297bf2e	1	/* SPDX-License-Identifier: GPL-2.0 OR MIT */
ba4e7d97 TH	2	/**************************************************************************
	3	*
	4	* Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
	5	* All Rights Reserved.
	6	*
	7	* Permission is hereby granted, free of charge, to any person obtaining a
	8	* copy of this software and associated documentation files (the
	9	* "Software"), to deal in the Software without restriction, including
	10	* without limitation the rights to use, copy, modify, merge, publish,
	11	* distribute, sub license, and/or sell copies of the Software, and to
	12	* permit persons to whom the Software is furnished to do so, subject to
	13	* the following conditions:
	14	*
	15	* The above copyright notice and this permission notice (including the
	16	* next paragraph) shall be included in all copies or substantial portions
	17	* of the Software.
	18	*
	19	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	20	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	21	* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
	22	* THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
	23	* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
	24	* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
	25	* USE OR OTHER DEALINGS IN THE SOFTWARE.
	26	*
	27	**************************************************************************/
	28
25d0479a JP	29	#define pr_fmt(fmt) "[TTM] " fmt
25d0479a JP	30
760285e7 DH	31	#include <drm/ttm/ttm_memory.h>
	32	#include <drm/ttm/ttm_module.h>
	33	#include <drm/ttm/ttm_page_alloc.h>
ba4e7d97 TH	34	#include <linux/spinlock.h>
	35	#include <linux/sched.h>
	36	#include <linux/wait.h>
	37	#include <linux/mm.h>
	38	#include <linux/module.h>
5a0e3ad6	39	#include <linux/slab.h>
ec3fe391	40	#include <linux/swap.h>
ba4e7d97	41
ba4e7d97 TH	42	#define TTM_MEMORY_ALLOC_RETRIES 4
ba4e7d97 TH	43
27eb1fa9 CK	44	struct ttm_mem_global ttm_mem_glob;
	45	EXPORT_SYMBOL(ttm_mem_glob);
	46
5fd9cbad TH	47	struct ttm_mem_zone {
	48	struct kobject kobj;
	49	struct ttm_mem_global *glob;
	50	const char *name;
	51	uint64_t zone_mem;
	52	uint64_t emer_mem;
	53	uint64_t max_mem;
	54	uint64_t swap_limit;
	55	uint64_t used_mem;
	56	};
	57
	58	static struct attribute ttm_mem_sys = {
	59	.name = "zone_memory",
	60	.mode = S_IRUGO
	61	};
	62	static struct attribute ttm_mem_emer = {
	63	.name = "emergency_memory",
	64	.mode = S_IRUGO \| S_IWUSR
	65	};
	66	static struct attribute ttm_mem_max = {
	67	.name = "available_memory",
	68	.mode = S_IRUGO \| S_IWUSR
	69	};
	70	static struct attribute ttm_mem_swap = {
	71	.name = "swap_limit",
	72	.mode = S_IRUGO \| S_IWUSR
	73	};
	74	static struct attribute ttm_mem_used = {
	75	.name = "used_memory",
	76	.mode = S_IRUGO
	77	};
	78
	79	static void ttm_mem_zone_kobj_release(struct kobject *kobj)
	80	{
	81	struct ttm_mem_zone *zone =
	82	container_of(kobj, struct ttm_mem_zone, kobj);
	83
25d0479a JP	84	pr_info("Zone %7s: Used memory at exit: %llu kiB\n",
25d0479a JP	85	zone->name, (unsigned long long)zone->used_mem >> 10);
5fd9cbad TH	86	kfree(zone);
	87	}
	88
	89	static ssize_t ttm_mem_zone_show(struct kobject *kobj,
	90	struct attribute *attr,
	91	char *buffer)
	92	{
	93	struct ttm_mem_zone *zone =
	94	container_of(kobj, struct ttm_mem_zone, kobj);
	95	uint64_t val = 0;
	96
	97	spin_lock(&zone->glob->lock);
	98	if (attr == &ttm_mem_sys)
	99	val = zone->zone_mem;
	100	else if (attr == &ttm_mem_emer)
	101	val = zone->emer_mem;
	102	else if (attr == &ttm_mem_max)
	103	val = zone->max_mem;
	104	else if (attr == &ttm_mem_swap)
	105	val = zone->swap_limit;
	106	else if (attr == &ttm_mem_used)
	107	val = zone->used_mem;
	108	spin_unlock(&zone->glob->lock);
	109
	110	return snprintf(buffer, PAGE_SIZE, "%llu\n",
	111	(unsigned long long) val >> 10);
	112	}
	113
	114	static void ttm_check_swapping(struct ttm_mem_global *glob);
	115
	116	static ssize_t ttm_mem_zone_store(struct kobject *kobj,
	117	struct attribute *attr,
	118	const char *buffer,
	119	size_t size)
	120	{
	121	struct ttm_mem_zone *zone =
	122	container_of(kobj, struct ttm_mem_zone, kobj);
	123	int chars;
	124	unsigned long val;
	125	uint64_t val64;
	126
	127	chars = sscanf(buffer, "%lu", &val);
	128	if (chars == 0)
	129	return size;
	130
	131	val64 = val;
	132	val64 <<= 10;
	133
	134	spin_lock(&zone->glob->lock);
	135	if (val64 > zone->zone_mem)
	136	val64 = zone->zone_mem;
	137	if (attr == &ttm_mem_emer) {
	138	zone->emer_mem = val64;
	139	if (zone->max_mem > val64)
	140	zone->max_mem = val64;
	141	} else if (attr == &ttm_mem_max) {
	142	zone->max_mem = val64;
	143	if (zone->emer_mem < val64)
	144	zone->emer_mem = val64;
	145	} else if (attr == &ttm_mem_swap)
	146	zone->swap_limit = val64;
	147	spin_unlock(&zone->glob->lock);
	148
	149	ttm_check_swapping(zone->glob);
150
151	return size;
152	}
153
154	static struct attribute *ttm_mem_zone_attrs[] = {
155	&ttm_mem_sys,
156	&ttm_mem_emer,
157	&ttm_mem_max,
158	&ttm_mem_swap,
159	&ttm_mem_used,
160	NULL
161	};
162
52cf25d0	163	static const struct sysfs_ops ttm_mem_zone_ops = {
5fd9cbad TH	164	.show = &ttm_mem_zone_show,
	165	.store = &ttm_mem_zone_store
	166	};
	167
	168	static struct kobj_type ttm_mem_zone_kobj_type = {
	169	.release = &ttm_mem_zone_kobj_release,
	170	.sysfs_ops = &ttm_mem_zone_ops,
	171	.default_attrs = ttm_mem_zone_attrs,
	172	};
	173
ec3fe391 RH	174	static struct attribute ttm_mem_global_lower_mem_limit = {
	175	.name = "lower_mem_limit",
	176	.mode = S_IRUGO \| S_IWUSR
	177	};
	178
	179	static ssize_t ttm_mem_global_show(struct kobject *kobj,
	180	struct attribute *attr,
	181	char *buffer)
	182	{
	183	struct ttm_mem_global *glob =
	184	container_of(kobj, struct ttm_mem_global, kobj);
	185	uint64_t val = 0;
	186
	187	spin_lock(&glob->lock);
	188	val = glob->lower_mem_limit;
	189	spin_unlock(&glob->lock);
	190	/* convert from number of pages to KB */
	191	val <<= (PAGE_SHIFT - 10);
	192	return snprintf(buffer, PAGE_SIZE, "%llu\n",
	193	(unsigned long long) val);
	194	}
	195
	196	static ssize_t ttm_mem_global_store(struct kobject *kobj,
	197	struct attribute *attr,
	198	const char *buffer,
	199	size_t size)
	200	{
	201	int chars;
	202	uint64_t val64;
	203	unsigned long val;
	204	struct ttm_mem_global *glob =
	205	container_of(kobj, struct ttm_mem_global, kobj);
	206
	207	chars = sscanf(buffer, "%lu", &val);
	208	if (chars == 0)
	209	return size;
	210
	211	val64 = val;
	212	/* convert from KB to number of pages */
	213	val64 >>= (PAGE_SHIFT - 10);
	214
	215	spin_lock(&glob->lock);
	216	glob->lower_mem_limit = val64;
	217	spin_unlock(&glob->lock);
	218
	219	return size;
	220	}
	221
ec3fe391 RH	222	static struct attribute *ttm_mem_global_attrs[] = {
	223	&ttm_mem_global_lower_mem_limit,
	224	NULL
	225	};
	226
	227	static const struct sysfs_ops ttm_mem_global_ops = {
	228	.show = &ttm_mem_global_show,
	229	.store = &ttm_mem_global_store,
	230	};
	231
5fd9cbad	232	static struct kobj_type ttm_mem_glob_kobj_type = {
ec3fe391 RH	233	.sysfs_ops = &ttm_mem_global_ops,
ec3fe391 RH	234	.default_attrs = ttm_mem_global_attrs,
5fd9cbad TH	235	};
	236
	237	static bool ttm_zones_above_swap_target(struct ttm_mem_global *glob,
	238	bool from_wq, uint64_t extra)
	239	{
	240	unsigned int i;
	241	struct ttm_mem_zone *zone;
	242	uint64_t target;
	243
	244	for (i = 0; i < glob->num_zones; ++i) {
	245	zone = glob->zones[i];
	246
	247	if (from_wq)
	248	target = zone->swap_limit;
	249	else if (capable(CAP_SYS_ADMIN))
	250	target = zone->emer_mem;
	251	else
	252	target = zone->max_mem;
	253
	254	target = (extra > target) ? 0ULL : target;
	255
	256	if (zone->used_mem > target)
	257	return true;
	258	}
	259	return false;
	260	}
	261
ba4e7d97 TH	262	/**
	263	* At this point we only support a single shrink callback.
	264	* Extend this if needed, perhaps using a linked list of callbacks.
	265	* Note that this function is reentrant:
	266	* many threads may try to swap out at any given time.
	267	*/
	268
5fd9cbad	269	static void ttm_shrink(struct ttm_mem_global *glob, bool from_wq,
dc947770	270	uint64_t extra, struct ttm_operation_ctx *ctx)
ba4e7d97 TH	271	{
ba4e7d97 TH	272	int ret;
ba4e7d97 TH	273
ba4e7d97 TH	274	spin_lock(&glob->lock);
ba4e7d97	275
5fd9cbad	276	while (ttm_zones_above_swap_target(glob, from_wq, extra)) {
ba4e7d97	277	spin_unlock(&glob->lock);
dc947770	278	ret = ttm_bo_swapout(glob->bo_glob, ctx);
ba4e7d97 TH	279	spin_lock(&glob->lock);
ba4e7d97 TH	280	if (unlikely(ret != 0))
a6c26af8	281	break;
ba4e7d97	282	}
a6c26af8	283
ba4e7d97 TH	284	spin_unlock(&glob->lock);
	285	}
	286
	287	static void ttm_shrink_work(struct work_struct *work)
	288	{
dc947770 RH	289	struct ttm_operation_ctx ctx = {
	290	.interruptible = false,
	291	.no_wait_gpu = false
	292	};
ba4e7d97 TH	293	struct ttm_mem_global *glob =
	294	container_of(work, struct ttm_mem_global, work);
	295
dc947770	296	ttm_shrink(glob, true, 0ULL, &ctx);
ba4e7d97 TH	297	}
ba4e7d97 TH	298
5fd9cbad TH	299	static int ttm_mem_init_kernel_zone(struct ttm_mem_global *glob,
	300	const struct sysinfo *si)
	301	{
	302	struct ttm_mem_zone zone = kzalloc(sizeof(zone), GFP_KERNEL);
	303	uint64_t mem;
759e4f83	304	int ret;
5fd9cbad TH	305
	306	if (unlikely(!zone))
	307	return -ENOMEM;
	308
	309	mem = si->totalram - si->totalhigh;
	310	mem *= si->mem_unit;
	311
	312	zone->name = "kernel";
	313	zone->zone_mem = mem;
	314	zone->max_mem = mem >> 1;
	315	zone->emer_mem = (mem >> 1) + (mem >> 2);
	316	zone->swap_limit = zone->max_mem - (mem >> 3);
	317	zone->used_mem = 0;
	318	zone->glob = glob;
	319	glob->zone_kernel = zone;
b642ed06 RD	320	ret = kobject_init_and_add(
b642ed06 RD	321	&zone->kobj, &ttm_mem_zone_kobj_type, &glob->kobj, zone->name);
759e4f83 TH	322	if (unlikely(ret != 0)) {
	323	kobject_put(&zone->kobj);
	324	return ret;
	325	}
	326	glob->zones[glob->num_zones++] = zone;
	327	return 0;
5fd9cbad TH	328	}
	329
	330	#ifdef CONFIG_HIGHMEM
	331	static int ttm_mem_init_highmem_zone(struct ttm_mem_global *glob,
	332	const struct sysinfo *si)
	333	{
46a79fa0	334	struct ttm_mem_zone *zone;
5fd9cbad	335	uint64_t mem;
759e4f83	336	int ret;
5fd9cbad	337
5fd9cbad TH	338	if (si->totalhigh == 0)
	339	return 0;
	340
46a79fa0 DC	341	zone = kzalloc(sizeof(*zone), GFP_KERNEL);
	342	if (unlikely(!zone))
	343	return -ENOMEM;
	344
5fd9cbad TH	345	mem = si->totalram;
	346	mem *= si->mem_unit;
	347
	348	zone->name = "highmem";
	349	zone->zone_mem = mem;
	350	zone->max_mem = mem >> 1;
	351	zone->emer_mem = (mem >> 1) + (mem >> 2);
	352	zone->swap_limit = zone->max_mem - (mem >> 3);
	353	zone->used_mem = 0;
	354	zone->glob = glob;
	355	glob->zone_highmem = zone;
b642ed06	356	ret = kobject_init_and_add(
109ab909 KC	357	&zone->kobj, &ttm_mem_zone_kobj_type, &glob->kobj, "%s",
109ab909 KC	358	zone->name);
759e4f83 TH	359	if (unlikely(ret != 0)) {
	360	kobject_put(&zone->kobj);
	361	return ret;
	362	}
	363	glob->zones[glob->num_zones++] = zone;
	364	return 0;
5fd9cbad TH	365	}
	366	#else
	367	static int ttm_mem_init_dma32_zone(struct ttm_mem_global *glob,
	368	const struct sysinfo *si)
	369	{
	370	struct ttm_mem_zone zone = kzalloc(sizeof(zone), GFP_KERNEL);
	371	uint64_t mem;
759e4f83	372	int ret;
5fd9cbad TH	373
	374	if (unlikely(!zone))
	375	return -ENOMEM;
	376
	377	mem = si->totalram;
	378	mem *= si->mem_unit;
	379
	380	/**
	381	* No special dma32 zone needed.
	382	*/
	383
ec42a6e7 DA	384	if (mem <= ((uint64_t) 1ULL << 32)) {
ec42a6e7 DA	385	kfree(zone);
5fd9cbad	386	return 0;
ec42a6e7	387	}
5fd9cbad TH	388
	389	/*
	390	* Limit max dma32 memory to 4GB for now
	391	* until we can figure out how big this
	392	* zone really is.
	393	*/
	394
	395	mem = ((uint64_t) 1ULL << 32);
	396	zone->name = "dma32";
	397	zone->zone_mem = mem;
	398	zone->max_mem = mem >> 1;
	399	zone->emer_mem = (mem >> 1) + (mem >> 2);
	400	zone->swap_limit = zone->max_mem - (mem >> 3);
	401	zone->used_mem = 0;
	402	zone->glob = glob;
	403	glob->zone_dma32 = zone;
b642ed06 RD	404	ret = kobject_init_and_add(
b642ed06 RD	405	&zone->kobj, &ttm_mem_zone_kobj_type, &glob->kobj, zone->name);
759e4f83 TH	406	if (unlikely(ret != 0)) {
	407	kobject_put(&zone->kobj);
	408	return ret;
	409	}
	410	glob->zones[glob->num_zones++] = zone;
	411	return 0;
5fd9cbad TH	412	}
	413	#endif
	414
ba4e7d97 TH	415	int ttm_mem_global_init(struct ttm_mem_global *glob)
	416	{
	417	struct sysinfo si;
5fd9cbad TH	418	int ret;
	419	int i;
	420	struct ttm_mem_zone *zone;
ba4e7d97 TH	421
	422	spin_lock_init(&glob->lock);
	423	glob->swap_queue = create_singlethread_workqueue("ttm_swap");
	424	INIT_WORK(&glob->work, ttm_shrink_work);
b642ed06 RD	425	ret = kobject_init_and_add(
b642ed06 RD	426	&glob->kobj, &ttm_mem_glob_kobj_type, ttm_get_kobj(), "memory_accounting");
759e4f83 TH	427	if (unlikely(ret != 0)) {
	428	kobject_put(&glob->kobj);
	429	return ret;
	430	}
ba4e7d97 TH	431
	432	si_meminfo(&si);
	433
ec3fe391 RH	434	/* set it as 0 by default to keep original behavior of OOM */
	435	glob->lower_mem_limit = 0;
	436
5fd9cbad TH	437	ret = ttm_mem_init_kernel_zone(glob, &si);
	438	if (unlikely(ret != 0))
	439	goto out_no_zone;
	440	#ifdef CONFIG_HIGHMEM
	441	ret = ttm_mem_init_highmem_zone(glob, &si);
	442	if (unlikely(ret != 0))
	443	goto out_no_zone;
	444	#else
	445	ret = ttm_mem_init_dma32_zone(glob, &si);
	446	if (unlikely(ret != 0))
	447	goto out_no_zone;
	448	#endif
	449	for (i = 0; i < glob->num_zones; ++i) {
	450	zone = glob->zones[i];
25d0479a JP	451	pr_info("Zone %7s: Available graphics memory: %llu kiB\n",
25d0479a JP	452	zone->name, (unsigned long long)zone->max_mem >> 10);
5fd9cbad	453	}
c96af79e	454	ttm_page_alloc_init(glob, glob->zone_kernel->max_mem/(2*PAGE_SIZE));
2334b75f	455	ttm_dma_page_alloc_init(glob, glob->zone_kernel->max_mem/(2*PAGE_SIZE));
ba4e7d97	456	return 0;
5fd9cbad TH	457	out_no_zone:
	458	ttm_mem_global_release(glob);
	459	return ret;
ba4e7d97	460	}
ba4e7d97 TH	461
	462	void ttm_mem_global_release(struct ttm_mem_global *glob)
	463	{
5fd9cbad TH	464	unsigned int i;
	465	struct ttm_mem_zone *zone;
	466
1403b1a3 PN	467	/* let the page allocator first stop the shrink work. */
1403b1a3 PN	468	ttm_page_alloc_fini();
2334b75f	469	ttm_dma_page_alloc_fini();
1403b1a3	470
ba4e7d97 TH	471	flush_workqueue(glob->swap_queue);
	472	destroy_workqueue(glob->swap_queue);
	473	glob->swap_queue = NULL;
5fd9cbad TH	474	for (i = 0; i < glob->num_zones; ++i) {
	475	zone = glob->zones[i];
	476	kobject_del(&zone->kobj);
	477	kobject_put(&zone->kobj);
1403b1a3	478	}
5fd9cbad TH	479	kobject_del(&glob->kobj);
5fd9cbad TH	480	kobject_put(&glob->kobj);
ba4e7d97	481	}
ba4e7d97	482
5fd9cbad	483	static void ttm_check_swapping(struct ttm_mem_global *glob)
ba4e7d97	484	{
5fd9cbad TH	485	bool needs_swapping = false;
	486	unsigned int i;
	487	struct ttm_mem_zone *zone;
ba4e7d97 TH	488
ba4e7d97 TH	489	spin_lock(&glob->lock);
5fd9cbad TH	490	for (i = 0; i < glob->num_zones; ++i) {
	491	zone = glob->zones[i];
	492	if (zone->used_mem > zone->swap_limit) {
	493	needs_swapping = true;
	494	break;
	495	}
	496	}
	497
ba4e7d97 TH	498	spin_unlock(&glob->lock);
	499
	500	if (unlikely(needs_swapping))
	501	(void)queue_work(glob->swap_queue, &glob->work);
	502
	503	}
	504
5fd9cbad TH	505	static void ttm_mem_global_free_zone(struct ttm_mem_global *glob,
	506	struct ttm_mem_zone *single_zone,
	507	uint64_t amount)
ba4e7d97	508	{
5fd9cbad TH	509	unsigned int i;
	510	struct ttm_mem_zone *zone;
	511
ba4e7d97	512	spin_lock(&glob->lock);
5fd9cbad TH	513	for (i = 0; i < glob->num_zones; ++i) {
	514	zone = glob->zones[i];
	515	if (single_zone && zone != single_zone)
	516	continue;
	517	zone->used_mem -= amount;
	518	}
ba4e7d97 TH	519	spin_unlock(&glob->lock);
	520	}
	521
5fd9cbad TH	522	void ttm_mem_global_free(struct ttm_mem_global *glob,
	523	uint64_t amount)
	524	{
	525	return ttm_mem_global_free_zone(glob, NULL, amount);
	526	}
4bfd75cb	527	EXPORT_SYMBOL(ttm_mem_global_free);
5fd9cbad	528
ec3fe391 RH	529	/*
	530	* check if the available mem is under lower memory limit
	531	*
	532	* a. if no swap disk at all or free swap space is under swap_mem_limit
	533	* but available system mem is bigger than sys_mem_limit, allow TTM
	534	* allocation;
	535	*
	536	* b. if the available system mem is less than sys_mem_limit but free
	537	* swap disk is bigger than swap_mem_limit, allow TTM allocation.
	538	*/
	539	bool
	540	ttm_check_under_lowerlimit(struct ttm_mem_global *glob,
	541	uint64_t num_pages,
	542	struct ttm_operation_ctx *ctx)
	543	{
	544	int64_t available;
	545
	546	if (ctx->flags & TTM_OPT_FLAG_FORCE_ALLOC)
	547	return false;
	548
	549	available = get_nr_swap_pages() + si_mem_available();
	550	available -= num_pages;
	551	if (available < glob->lower_mem_limit)
	552	return true;
	553
	554	return false;
	555	}
	556	EXPORT_SYMBOL(ttm_check_under_lowerlimit);
	557
ba4e7d97	558	static int ttm_mem_global_reserve(struct ttm_mem_global *glob,
5fd9cbad TH	559	struct ttm_mem_zone *single_zone,
5fd9cbad TH	560	uint64_t amount, bool reserve)
ba4e7d97 TH	561	{
ba4e7d97 TH	562	uint64_t limit;
ba4e7d97	563	int ret = -ENOMEM;
5fd9cbad TH	564	unsigned int i;
5fd9cbad TH	565	struct ttm_mem_zone *zone;
ba4e7d97 TH	566
ba4e7d97 TH	567	spin_lock(&glob->lock);
5fd9cbad TH	568	for (i = 0; i < glob->num_zones; ++i) {
	569	zone = glob->zones[i];
	570	if (single_zone && zone != single_zone)
	571	continue;
ba4e7d97	572
5fd9cbad TH	573	limit = (capable(CAP_SYS_ADMIN)) ?
5fd9cbad TH	574	zone->emer_mem : zone->max_mem;
ba4e7d97	575
5fd9cbad TH	576	if (zone->used_mem > limit)
	577	goto out_unlock;
	578	}
ba4e7d97 TH	579
ba4e7d97 TH	580	if (reserve) {
5fd9cbad TH	581	for (i = 0; i < glob->num_zones; ++i) {
	582	zone = glob->zones[i];
	583	if (single_zone && zone != single_zone)
	584	continue;
	585	zone->used_mem += amount;
	586	}
ba4e7d97	587	}
5fd9cbad	588
ba4e7d97 TH	589	ret = 0;
	590	out_unlock:
	591	spin_unlock(&glob->lock);
	592	ttm_check_swapping(glob);
	593
	594	return ret;
	595	}
	596
5fd9cbad TH	597
	598	static int ttm_mem_global_alloc_zone(struct ttm_mem_global *glob,
	599	struct ttm_mem_zone *single_zone,
	600	uint64_t memory,
279c01f6	601	struct ttm_operation_ctx *ctx)
ba4e7d97 TH	602	{
	603	int count = TTM_MEMORY_ALLOC_RETRIES;
	604
5fd9cbad TH	605	while (unlikely(ttm_mem_global_reserve(glob,
	606	single_zone,
	607	memory, true)
ba4e7d97	608	!= 0)) {
279c01f6	609	if (ctx->no_wait_gpu)
ba4e7d97 TH	610	return -ENOMEM;
	611	if (unlikely(count-- == 0))
	612	return -ENOMEM;
dc947770	613	ttm_shrink(glob, false, memory + (memory >> 2) + 16, ctx);
ba4e7d97 TH	614	}
	615
	616	return 0;
	617	}
	618
5fd9cbad	619	int ttm_mem_global_alloc(struct ttm_mem_global *glob, uint64_t memory,
279c01f6	620	struct ttm_operation_ctx *ctx)
5fd9cbad TH	621	{
	622	/**
	623	* Normal allocations of kernel memory are registered in
	624	* all zones.
	625	*/
	626
279c01f6	627	return ttm_mem_global_alloc_zone(glob, NULL, memory, ctx);
5fd9cbad	628	}
4bfd75cb	629	EXPORT_SYMBOL(ttm_mem_global_alloc);
5fd9cbad TH	630
5fd9cbad TH	631	int ttm_mem_global_alloc_page(struct ttm_mem_global *glob,
9de2fb99 RH	632	struct page *page, uint64_t size,
9de2fb99 RH	633	struct ttm_operation_ctx *ctx)
5fd9cbad	634	{
5fd9cbad TH	635	struct ttm_mem_zone *zone = NULL;
	636
	637	/**
	638	* Page allocations may be registed in a single zone
	639	* only if highmem or !dma32.
	640	*/
	641
	642	#ifdef CONFIG_HIGHMEM
	643	if (PageHighMem(page) && glob->zone_highmem != NULL)
	644	zone = glob->zone_highmem;
	645	#else
	646	if (glob->zone_dma32 && page_to_pfn(page) > 0x00100000UL)
	647	zone = glob->zone_kernel;
	648	#endif
9de2fb99	649	return ttm_mem_global_alloc_zone(glob, zone, size, ctx);
5fd9cbad TH	650	}
5fd9cbad TH	651
d188bfa5 CK	652	void ttm_mem_global_free_page(struct ttm_mem_global glob, struct page page,
d188bfa5 CK	653	uint64_t size)
5fd9cbad TH	654	{
	655	struct ttm_mem_zone *zone = NULL;
	656
	657	#ifdef CONFIG_HIGHMEM
	658	if (PageHighMem(page) && glob->zone_highmem != NULL)
	659	zone = glob->zone_highmem;
	660	#else
	661	if (glob->zone_dma32 && page_to_pfn(page) > 0x00100000UL)
	662	zone = glob->zone_kernel;
	663	#endif
d188bfa5	664	ttm_mem_global_free_zone(glob, zone, size);
5fd9cbad TH	665	}
5fd9cbad TH	666
ba4e7d97 TH	667	size_t ttm_round_pot(size_t size)
	668	{
	669	if ((size & (size - 1)) == 0)
	670	return size;
	671	else if (size > PAGE_SIZE)
	672	return PAGE_ALIGN(size);
	673	else {
	674	size_t tmp_size = 4;
	675
	676	while (tmp_size < size)
	677	tmp_size <<= 1;
	678
	679	return tmp_size;
	680	}
	681	return 0;
	682	}
4bfd75cb	683	EXPORT_SYMBOL(ttm_round_pot);
ecf6a637 KW	684
	685	uint64_t ttm_get_kernel_zone_memory_size(struct ttm_mem_global *glob)
	686	{
	687	return glob->zone_kernel->max_mem;
	688	}
	689	EXPORT_SYMBOL(ttm_get_kernel_zone_memory_size);