/shared-core/

• ../
• Makefile.am
• drm.h
• drm_pciids.txt
• drm_sarea.h
• i915_dma.c
• i915_drm.h
• i915_drv.h
• i915_irq.c
• i915_mem.c
• imagine_drv.h
• mach64_dma.c
• mach64_drm.h
• mach64_drv.h
• mach64_irq.c
• mach64_state.c
• mga_dma.c
• mga_drm.h
• mga_drv.h
• mga_irq.c
• mga_state.c
• mga_ucode.h
• mga_warp.c
• nouveau_drm.h
• nouveau_drv.h
• nouveau_fifo.c
• nouveau_irq.c
• nouveau_mem.c
• nouveau_object.c
• nouveau_reg.h
• nouveau_state.c
• nv04_fb.c
• nv04_graph.c
• nv04_mc.c
• nv04_timer.c
• nv10_fb.c
• nv10_graph.c
• nv20_graph.c
• nv30_graph.c
• nv40_fb.c
• nv40_graph.c
• nv40_mc.c
• nv_drv.h
• r128_cce.c
• r128_drm.h
• r128_drv.h
• r128_irq.c
• r128_state.c
• r300_cmdbuf.c
• r300_reg.h
• radeon_cp.c
• radeon_drm.h
• radeon_drv.h
• radeon_irq.c
• radeon_mem.c
• radeon_state.c
• savage_bci.c
• savage_drm.h
• savage_drv.h
• savage_state.c
• sis_drm.h
• sis_drv.h
• sis_ds.c
• sis_ds.h
• sis_mm.c
• tdfx_drv.h
• via_3d_reg.h
• via_dma.c
• via_drm.h
• via_drv.c
• via_drv.h
• via_ds.c
• via_ds.h
• via_irq.c
• via_map.c
• via_mm.c
• via_mm.h
• via_verifier.c
• via_verifier.h
• via_video.c

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

/*
 * 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 "drmP.h"
#include <linux/slab.h>

unsigned long drm_mm_tail_space(struct drm_mm *mm)
{
	struct list_head *tail_node;
	struct drm_mm_node *entry;

	tail_node = mm->ml_entry.prev;
	entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
	if (!entry->free)
		return 0;

	return entry->size;
}

int drm_mm_remove_space_from_tail(struct drm_mm *mm, unsigned long size)
{
	struct list_head *tail_node;
	struct drm_mm_node *entry;

	tail_node = mm->ml_entry.prev;
	entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
	if (!entry->free)
		return -ENOMEM;

	if (entry->size <= size)
		return -ENOMEM;

	entry->size -= size;
	return 0;
}


static int drm_mm_create_tail_node(struct drm_mm *mm,
			    unsigned long start,
			    unsigned long size)
{
	struct drm_mm_node *child;

	child = (struct drm_mm_node *)
		drm_ctl_alloc(sizeof(*child), DRM_MEM_MM);
	if (!child)
		return -ENOMEM;

	child->free = 1;
	child->size = size;
	child->start = start;
	child->mm = mm;

	list_add_tail(&child->ml_entry, &mm->ml_entry);
	list_add_tail(&child->fl_entry, &mm->fl_entry);

	return 0;
}


int drm_mm_add_space_to_tail(struct drm_mm *mm, unsigned long size)
{
	struct list_head *tail_node;
	struct drm_mm_node *entry;

	tail_node = mm->ml_entry.prev;
	entry = list_entry(tail_node, struct drm_mm_node, ml_entry);
	if (!entry->free) {
		return drm_mm_create_tail_node(mm, entry->start + entry->size, size);
	}
	entry->size += size;
	return 0;
}

static struct drm_mm_node *drm_mm_split_at_start(struct drm_mm_node *parent,
					    unsigned long size)
{
	struct drm_mm_node *child;

	child = (struct drm_mm_node *)
		drm_ctl_alloc(sizeof(*child), DRM_MEM_MM);
	if (!child)
		return NULL;

	INIT_LIST_HEAD(&child->fl_entry);

	child->free = 0;
	child->size = size;
	child->start = parent->start;
	child->mm = parent->mm;

	list_add_tail(&child->ml_entry, &parent->ml_entry);
	INIT_LIST_HEAD(&child->fl_entry);

	parent->size -= size;
	parent->start += size;
	return child;
}

struct drm_mm_node *drm_mm_get_block(struct drm_mm_node * parent,
				unsigned long size, unsigned alignment)
{

	struct drm_mm_node *align_splitoff = NULL;
	struct drm_mm_node *child;
	unsigned tmp = 0;

	if (alignment)
		tmp = parent->start % alignment;

	if (tmp) {
		align_splitoff = drm_mm_split_at_start(parent, alignment - tmp);
		if (!align_splitoff)
			return NULL;
	}

	if (parent->size == size) {
		list_del_init(&parent->fl_entry);
		parent->free = 0;
		return parent;
	} else {
		child = drm_mm_split_at_start(parent, size);
	}

	if (align_splitoff)
		drm_mm_put_block(align_splitoff);

	return child;
}
EXPORT_SYMBOL(drm_mm_get_block);

/*
 * Put a block. Merge with the previous and / or next block if they are free.