linux-imx

/**************************************************************************

 *

 * Copyright 2006 Tungsten Graphics, Inc., Bismarck, ND., USA.

 * Copyright 2016 Intel Corporation

 * All Rights Reserved.

 *

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 * the following conditions:

 *

 * The above copyright notice and this permission notice (including the

 * next paragraph) shall be included in all copies or substantial portions

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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

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 **************************************************************************/

​

/*

 * Generic simple memory manager implementation. Intended to be used as a base

 * class implementation for more advanced memory managers.

 *

 * Note that the algorithm used is quite simple and there might be substantial

 * performance gains if a smarter free list is implemented. Currently it is

 * just an unordered stack of free regions. This could easily be improved if

 * an RB-tree is used instead. At least if we expect heavy fragmentation.

 *

 * Aligned allocations can also see improvement.

 *

 * Authors:

 * Thomas Hellström <thomas-at-tungstengraphics-dot-com>

 */

​

#include <drm/drmP.h>

#include <drm/drm_mm.h>

#include <linux/slab.h>

#include <linux/seq_file.h>

#include <linux/export.h>

#include <linux/interval_tree_generic.h>

​

/**

 * DOC: Overview

 *

 * drm_mm provides a simple range allocator. The drivers are free to use the

 * resource allocator from the linux core if it suits them, the upside of drm_mm

 * is that it's in the DRM core. Which means that it's easier to extend for

 * some of the crazier special purpose needs of gpus.

 *

 * The main data struct is &drm_mm, allocations are tracked in &drm_mm_node.

 * Drivers are free to embed either of them into their own suitable

 * datastructures. drm_mm itself will not do any memory allocations of its own,

 * so if drivers choose not to embed nodes they need to still allocate them