ttm_bo_manager.c

Go to the documentation of this file.

/**************************************************************************
 *
 * Copyright (c) 2007-2010 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 <drm/ttm/ttm_module.h>
#include <drm/ttm/ttm_bo_driver.h>
#include <drm/ttm/ttm_placement.h>
#include <drm/drm_mm.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/module.h>

struct ttm_range_manager {
    struct drm_mm mm;
    spinlock_t lock;
};

static int ttm_bo_man_get_node(struct ttm_mem_type_manager *man,
                   struct ttm_buffer_object *bo,
                   struct ttm_placement *placement,
                   struct ttm_mem_reg *mem)
{
    struct ttm_range_manager *rman = (struct ttm_range_manager *) man->priv;
    struct drm_mm *mm = &rman->mm;
    struct drm_mm_node *node = NULL;
    unsigned long lpfn;
    int ret;

    lpfn = placement->lpfn;
    if (!lpfn)
        lpfn = man->size;
    do {
        ret = drm_mm_pre_get(mm);
        if (unlikely(ret))
            return ret;

        spin_lock(&rman->lock);
        node = drm_mm_search_free_in_range(mm,
                    mem->num_pages, mem->page_alignment,
                    placement->fpfn, lpfn, 1);
        if (unlikely(node == NULL)) {
            spin_unlock(&rman->lock);
            return 0;
        }
        node = drm_mm_get_block_atomic_range(node, mem->num_pages,
                             mem->page_alignment,
                             placement->fpfn,
                             lpfn);
        spin_unlock(&rman->lock);
    } while (node == NULL);

    mem->mm_node = node;
    mem->start = node->start;
    return 0;
}

static void ttm_bo_man_put_node(struct ttm_mem_type_manager *man,
                struct ttm_mem_reg *mem)
{
    struct ttm_range_manager *rman = (struct ttm_range_manager *) man->priv;

    if (mem->mm_node) {
        spin_lock(&rman->lock);
        drm_mm_put_block(mem->mm_node);
        spin_unlock(&rman->lock);
        mem->mm_node = NULL;
    }
}

static int ttm_bo_man_init(struct ttm_mem_type_manager *man,
               unsigned long p_size)
{
    struct ttm_range_manager *rman;
    int ret;

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

    ret = drm_mm_init(&rman->mm, 0, p_size);
    if (ret) {
        kfree(rman);
        return ret;
    }

    spin_lock_init(&rman->lock);
    man->priv = rman;
    return 0;
}

static int ttm_bo_man_takedown(struct ttm_mem_type_manager *man)
{
    struct ttm_range_manager *rman = (struct ttm_range_manager *) man->priv;
    struct drm_mm *mm = &rman->mm;

    spin_lock(&rman->lock);
    if (drm_mm_clean(mm)) {
        drm_mm_takedown(mm);
        spin_unlock(&rman->lock);
        kfree(rman);
        man->priv = NULL;
        return 0;
    }
    spin_unlock(&rman->lock);
    return -EBUSY;
}

static void ttm_bo_man_debug(struct ttm_mem_type_manager *man,
                 const char *prefix)
{
    struct ttm_range_manager *rman = (struct ttm_range_manager *) man->priv;

    spin_lock(&rman->lock);
    drm_mm_debug_table(&rman->mm, prefix);
    spin_unlock(&rman->lock);
}

const struct ttm_mem_type_manager_func ttm_bo_manager_func = {
    ttm_bo_man_init,
    ttm_bo_man_takedown,
    ttm_bo_man_get_node,
    ttm_bo_man_put_node,
    ttm_bo_man_debug
};
EXPORT_SYMBOL(ttm_bo_manager_func);