drivers/char/drm/radeon_mem.c - maze/linux - Git at Google

 /* radeon_mem.c -- Simple GART/fb memory manager for radeon -*- linux-c -*- */
 /*
  * Copyright (C) The Weather Channel, Inc.  2002.  All Rights Reserved.
  *
  * The Weather Channel (TM) funded Tungsten Graphics to develop the
  * initial release of the Radeon 8500 driver under the XFree86 license.
  * This notice must be preserved.
  *
  * 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, sublicense,
  * 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 NONINFRINGEMENT.  IN NO EVENT SHALL
  * PRECISION INSIGHT 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:
  *    Keith Whitwell <keith@tungstengraphics.com>
  */

 #include "drmP.h"
 #include "drm.h"
 #include "radeon_drm.h"
 #include "radeon_drv.h"

 /* Very simple allocator for GART memory, working on a static range
  * already mapped into each client's address space.
  */

 static struct mem_block *split_block(struct mem_block *p, int start, int size,
 				     DRMFILE filp)
 {
 	/* Maybe cut off the start of an existing block */
 	if (start > p->start) {
 		struct mem_block *newblock =
 		    drm_alloc(sizeof(*newblock), DRM_MEM_BUFS);
 		if (!newblock)
 			goto out;
 		newblock->start = start;
 		newblock->size = p->size - (start - p->start);
 		newblock->filp = NULL;
 		newblock->next = p->next;
 		newblock->prev = p;
 		p->next->prev = newblock;
 		p->next = newblock;
 		p->size -= newblock->size;
 		p = newblock;
 	}

 	/* Maybe cut off the end of an existing block */
 	if (size < p->size) {
 		struct mem_block *newblock =
 		    drm_alloc(sizeof(*newblock), DRM_MEM_BUFS);
 		if (!newblock)
 			goto out;
 		newblock->start = start + size;
 		newblock->size = p->size - size;
 		newblock->filp = NULL;
 		newblock->next = p->next;
 		newblock->prev = p;
 		p->next->prev = newblock;
 		p->next = newblock;
 		p->size = size;
 	}

       out:
 	/* Our block is in the middle */
 	p->filp = filp;
 	return p;
 }

 static struct mem_block *alloc_block(struct mem_block *heap, int size,
 				     int align2, DRMFILE filp)
 {
 	struct mem_block *p;
 	int mask = (1 << align2) - 1;

 	list_for_each(p, heap) {
 		int start = (p->start + mask) & ~mask;
 		if (p->filp == 0 && start + size <= p->start + p->size)
 			return split_block(p, start, size, filp);
 	}

 	return NULL;
 }

 static struct mem_block *find_block(struct mem_block *heap, int start)
 {
 	struct mem_block *p;

 	list_for_each(p, heap)
 	    if (p->start == start)
 		return p;

 	return NULL;
 }

 static void free_block(struct mem_block *p)
 {
 	p->filp = NULL;

 	/* Assumes a single contiguous range.  Needs a special filp in
 	 * 'heap' to stop it being subsumed.
 	 */
 	if (p->next->filp == 0) {
 		struct mem_block *q = p->next;
 		p->size += q->size;
 		p->next = q->next;
 		p->next->prev = p;
 		drm_free(q, sizeof(*q), DRM_MEM_BUFS);
 	}

 	if (p->prev->filp == 0) {
 		struct mem_block *q = p->prev;
 		q->size += p->size;
 		q->next = p->next;
 		q->next->prev = q;
 		drm_free(p, sizeof(*q), DRM_MEM_BUFS);
 	}
 }

 /* Initialize.  How to check for an uninitialized heap?
  */
 static int init_heap(struct mem_block **heap, int start, int size)
 {
 	struct mem_block *blocks = drm_alloc(sizeof(*blocks), DRM_MEM_BUFS);

 	if (!blocks)
 		return DRM_ERR(ENOMEM);

 	*heap = drm_alloc(sizeof(**heap), DRM_MEM_BUFS);
 	if (!*heap) {
 		drm_free(blocks, sizeof(*blocks), DRM_MEM_BUFS);
 		return DRM_ERR(ENOMEM);
 	}

 	blocks->start = start;
 	blocks->size = size;
 	blocks->filp = NULL;
 	blocks->next = blocks->prev = *heap;

 	memset(*heap, 0, sizeof(**heap));
 	(*heap)->filp = (DRMFILE) - 1;
 	(*heap)->next = (*heap)->prev = blocks;
 	return 0;
 }

 /* Free all blocks associated with the releasing file.
  */
 void radeon_mem_release(DRMFILE filp, struct mem_block *heap)
 {
 	struct mem_block *p;

 	if (!heap || !heap->next)
 		return;

 	list_for_each(p, heap) {
 		if (p->filp == filp)
 			p->filp = NULL;
 	}

 	/* Assumes a single contiguous range.  Needs a special filp in
 	 * 'heap' to stop it being subsumed.
 	 */
 	list_for_each(p, heap) {
 		while (p->filp == 0 && p->next->filp == 0) {
 			struct mem_block *q = p->next;
 			p->size += q->size;
 			p->next = q->next;
 			p->next->prev = p;
 			drm_free(q, sizeof(*q), DRM_MEM_DRIVER);
 		}
 	}
 }

 /* Shutdown.
  */
 void radeon_mem_takedown(struct mem_block **heap)
 {
 	struct mem_block *p;

 	if (!*heap)
 		return;

 	for (p = (*heap)->next; p != *heap;) {
 		struct mem_block *q = p;
 		p = p->next;
 		drm_free(q, sizeof(*q), DRM_MEM_DRIVER);
 	}

 	drm_free(*heap, sizeof(**heap), DRM_MEM_DRIVER);
 	*heap = NULL;
 }

 /* IOCTL HANDLERS */

 static struct mem_block **get_heap(drm_radeon_private_t * dev_priv, int region)
 {
 	switch (region) {
 	case RADEON_MEM_REGION_GART:
 		return &dev_priv->gart_heap;
 	case RADEON_MEM_REGION_FB:
 		return &dev_priv->fb_heap;
 	default:
 		return NULL;
 	}
 }

 int radeon_mem_alloc(DRM_IOCTL_ARGS)
 {
 	DRM_DEVICE;
 	drm_radeon_private_t *dev_priv = dev->dev_private;
 	drm_radeon_mem_alloc_t alloc;
 	struct mem_block *block, **heap;

 	if (!dev_priv) {
 		DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
 		return DRM_ERR(EINVAL);
 	}

 	DRM_COPY_FROM_USER_IOCTL(alloc, (drm_radeon_mem_alloc_t __user *) data,
 				 sizeof(alloc));

 	heap = get_heap(dev_priv, alloc.region);
 	if (!heap || !*heap)
 		return DRM_ERR(EFAULT);

 	/* Make things easier on ourselves: all allocations at least
 	 * 4k aligned.
 	 */
 	if (alloc.alignment < 12)
 		alloc.alignment = 12;

 	block = alloc_block(*heap, alloc.size, alloc.alignment, filp);

 	if (!block)
 		return DRM_ERR(ENOMEM);

 	if (DRM_COPY_TO_USER(alloc.region_offset, &block->start, sizeof(int))) {
 		DRM_ERROR("copy_to_user\n");
 		return DRM_ERR(EFAULT);
 	}

 	return 0;
 }

 int radeon_mem_free(DRM_IOCTL_ARGS)
 {
 	DRM_DEVICE;
 	drm_radeon_private_t *dev_priv = dev->dev_private;
 	drm_radeon_mem_free_t memfree;
 	struct mem_block *block, **heap;

 	if (!dev_priv) {
 		DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
 		return DRM_ERR(EINVAL);
 	}

 	DRM_COPY_FROM_USER_IOCTL(memfree, (drm_radeon_mem_free_t __user *) data,
 				 sizeof(memfree));

 	heap = get_heap(dev_priv, memfree.region);
 	if (!heap || !*heap)
 		return DRM_ERR(EFAULT);

 	block = find_block(*heap, memfree.region_offset);
 	if (!block)
 		return DRM_ERR(EFAULT);

 	if (block->filp != filp)
 		return DRM_ERR(EPERM);

 	free_block(block);
 	return 0;
 }

 int radeon_mem_init_heap(DRM_IOCTL_ARGS)
 {
 	DRM_DEVICE;
 	drm_radeon_private_t *dev_priv = dev->dev_private;
 	drm_radeon_mem_init_heap_t initheap;
 	struct mem_block **heap;

 	if (!dev_priv) {
 		DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
 		return DRM_ERR(EINVAL);
 	}

 	DRM_COPY_FROM_USER_IOCTL(initheap,
 				 (drm_radeon_mem_init_heap_t __user *) data,
 				 sizeof(initheap));

 	heap = get_heap(dev_priv, initheap.region);
 	if (!heap)
 		return DRM_ERR(EFAULT);

 	if (*heap) {
 		DRM_ERROR("heap already initialized?");
 		return DRM_ERR(EFAULT);
 	}

 	return init_heap(heap, initheap.start, initheap.size);
 }
	/* radeon_mem.c -- Simple GART/fb memory manager for radeon -- linux-c -- */
	/*
	* Copyright (C) The Weather Channel, Inc. 2002. All Rights Reserved.
	*
	* The Weather Channel (TM) funded Tungsten Graphics to develop the
	* initial release of the Radeon 8500 driver under the XFree86 license.
	* This notice must be preserved.
	*
	* 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, sublicense,
	* 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 NONINFRINGEMENT. IN NO EVENT SHALL
	* PRECISION INSIGHT 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:
	* Keith Whitwell <keith@tungstengraphics.com>
	*/

	#include "drmP.h"
	#include "drm.h"
	#include "radeon_drm.h"
	#include "radeon_drv.h"

	/* Very simple allocator for GART memory, working on a static range
	* already mapped into each client's address space.
	*/

	static struct mem_block split_block(struct mem_block p, int start, int size,
	DRMFILE filp)
	{
	/* Maybe cut off the start of an existing block */
	if (start > p->start) {
	struct mem_block *newblock =
	drm_alloc(sizeof(*newblock), DRM_MEM_BUFS);
	if (!newblock)
	goto out;
	newblock->start = start;
	newblock->size = p->size - (start - p->start);
	newblock->filp = NULL;
	newblock->next = p->next;
	newblock->prev = p;
	p->next->prev = newblock;
	p->next = newblock;
	p->size -= newblock->size;
	p = newblock;
	}

	/* Maybe cut off the end of an existing block */
	if (size < p->size) {
	struct mem_block *newblock =
	drm_alloc(sizeof(*newblock), DRM_MEM_BUFS);
	if (!newblock)
	goto out;
	newblock->start = start + size;
	newblock->size = p->size - size;
	newblock->filp = NULL;
	newblock->next = p->next;
	newblock->prev = p;
	p->next->prev = newblock;
	p->next = newblock;
	p->size = size;
	}

	out:
	/* Our block is in the middle */
	p->filp = filp;
	return p;
	}

	static struct mem_block alloc_block(struct mem_block heap, int size,
	int align2, DRMFILE filp)
	{
	struct mem_block *p;
	int mask = (1 << align2) - 1;

	list_for_each(p, heap) {
	int start = (p->start + mask) & ~mask;
	if (p->filp == 0 && start + size <= p->start + p->size)
	return split_block(p, start, size, filp);
	}

	return NULL;
	}

	static struct mem_block find_block(struct mem_block heap, int start)
	{
	struct mem_block *p;

	list_for_each(p, heap)
	if (p->start == start)
	return p;

	return NULL;
	}

	static void free_block(struct mem_block *p)
	{
	p->filp = NULL;

	/* Assumes a single contiguous range. Needs a special filp in
	* 'heap' to stop it being subsumed.
	*/
	if (p->next->filp == 0) {
	struct mem_block *q = p->next;
	p->size += q->size;
	p->next = q->next;
	p->next->prev = p;
	drm_free(q, sizeof(*q), DRM_MEM_BUFS);
	}

	if (p->prev->filp == 0) {
	struct mem_block *q = p->prev;
	q->size += p->size;
	q->next = p->next;
	q->next->prev = q;
	drm_free(p, sizeof(*q), DRM_MEM_BUFS);
	}
	}

	/* Initialize. How to check for an uninitialized heap?
	*/
	static int init_heap(struct mem_block **heap, int start, int size)
	{
	struct mem_block blocks = drm_alloc(sizeof(blocks), DRM_MEM_BUFS);

	if (!blocks)
	return DRM_ERR(ENOMEM);

	heap = drm_alloc(sizeof(*heap), DRM_MEM_BUFS);
	if (!*heap) {
	drm_free(blocks, sizeof(*blocks), DRM_MEM_BUFS);
	return DRM_ERR(ENOMEM);
	}

	blocks->start = start;
	blocks->size = size;
	blocks->filp = NULL;
	blocks->next = blocks->prev = *heap;

	memset(heap, 0, sizeof(*heap));
	(*heap)->filp = (DRMFILE) - 1;
	(heap)->next = (heap)->prev = blocks;
	return 0;
	}

	/* Free all blocks associated with the releasing file.
	*/
	void radeon_mem_release(DRMFILE filp, struct mem_block *heap)
	{
	struct mem_block *p;

	if (!heap \|\| !heap->next)
	return;

	list_for_each(p, heap) {
	if (p->filp == filp)
	p->filp = NULL;
	}

	/* Assumes a single contiguous range. Needs a special filp in
	* 'heap' to stop it being subsumed.
	*/
	list_for_each(p, heap) {
	while (p->filp == 0 && p->next->filp == 0) {
	struct mem_block *q = p->next;
	p->size += q->size;
	p->next = q->next;
	p->next->prev = p;
	drm_free(q, sizeof(*q), DRM_MEM_DRIVER);
	}
	}
	}

	/* Shutdown.
	*/
	void radeon_mem_takedown(struct mem_block **heap)
	{
	struct mem_block *p;

	if (!*heap)
	return;

	for (p = (heap)->next; p != heap;) {
	struct mem_block *q = p;
	p = p->next;
	drm_free(q, sizeof(*q), DRM_MEM_DRIVER);
	}

	drm_free(heap, sizeof(*heap), DRM_MEM_DRIVER);
	*heap = NULL;
	}

	/* IOCTL HANDLERS */

	static struct mem_block *get_heap(drm_radeon_private_t dev_priv, int region)
	{
	switch (region) {
	case RADEON_MEM_REGION_GART:
	return &dev_priv->gart_heap;
	case RADEON_MEM_REGION_FB:
	return &dev_priv->fb_heap;
	default:
	return NULL;
	}
	}

	int radeon_mem_alloc(DRM_IOCTL_ARGS)
	{
	DRM_DEVICE;
	drm_radeon_private_t *dev_priv = dev->dev_private;
	drm_radeon_mem_alloc_t alloc;
	struct mem_block block, *heap;

	if (!dev_priv) {
	DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
	return DRM_ERR(EINVAL);
	}

	DRM_COPY_FROM_USER_IOCTL(alloc, (drm_radeon_mem_alloc_t __user *) data,
	sizeof(alloc));

	heap = get_heap(dev_priv, alloc.region);
	if (!heap \|\| !*heap)
	return DRM_ERR(EFAULT);

	/* Make things easier on ourselves: all allocations at least
	* 4k aligned.
	*/
	if (alloc.alignment < 12)
	alloc.alignment = 12;

	block = alloc_block(*heap, alloc.size, alloc.alignment, filp);

	if (!block)
	return DRM_ERR(ENOMEM);

	if (DRM_COPY_TO_USER(alloc.region_offset, &block->start, sizeof(int))) {
	DRM_ERROR("copy_to_user\n");
	return DRM_ERR(EFAULT);
	}

	return 0;
	}

	int radeon_mem_free(DRM_IOCTL_ARGS)
	{
	DRM_DEVICE;
	drm_radeon_private_t *dev_priv = dev->dev_private;
	drm_radeon_mem_free_t memfree;
	struct mem_block block, *heap;

	if (!dev_priv) {
	DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
	return DRM_ERR(EINVAL);
	}

	DRM_COPY_FROM_USER_IOCTL(memfree, (drm_radeon_mem_free_t __user *) data,
	sizeof(memfree));

	heap = get_heap(dev_priv, memfree.region);
	if (!heap \|\| !*heap)
	return DRM_ERR(EFAULT);

	block = find_block(*heap, memfree.region_offset);
	if (!block)
	return DRM_ERR(EFAULT);

	if (block->filp != filp)
	return DRM_ERR(EPERM);

	free_block(block);
	return 0;
	}

	int radeon_mem_init_heap(DRM_IOCTL_ARGS)
	{
	DRM_DEVICE;
	drm_radeon_private_t *dev_priv = dev->dev_private;
	drm_radeon_mem_init_heap_t initheap;
	struct mem_block **heap;

	if (!dev_priv) {
	DRM_ERROR("%s called with no initialization\n", __FUNCTION__);
	return DRM_ERR(EINVAL);
	}

	DRM_COPY_FROM_USER_IOCTL(initheap,
	(drm_radeon_mem_init_heap_t __user *) data,
	sizeof(initheap));

	heap = get_heap(dev_priv, initheap.region);
	if (!heap)
	return DRM_ERR(EFAULT);

	if (*heap) {
	DRM_ERROR("heap already initialized?");
	return DRM_ERR(EFAULT);
	}

	return init_heap(heap, initheap.start, initheap.size);
	}