drm/src/drm_dma.c

/*
 * Copyright (c) 2006, 2012, Oracle and/or its affiliates. All rights reserved.
 */

/*
 * Copyright (c) 2012 Intel Corporation.  All rights reserved.
 */

/**
 * \file drm_dma.c
 * DMA IOCTL and function support
 *
 * \author Rickard E. (Rik) Faith <faith@valinux.com>
 * \author Gareth Hughes <gareth@valinux.com>
 */

/*
 * Created: Fri Mar 19 14:30:16 1999 by faith@valinux.com
 *
 * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * 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, 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
 * VA LINUX SYSTEMS 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.
 */

#include "drmP.h"

/**
 * Initialize the DMA data.
 *
 * \param dev DRM device.
 * \return zero on success or a negative value on failure.
 *
 * Allocate and initialize a drm_device_dma structure.
 */
int drm_dma_setup(struct drm_device *dev)
{
    int i;

    dev->dma = kmalloc(sizeof(*dev->dma), GFP_KERNEL);
    if (!dev->dma)
        return -ENOMEM;

    (void) memset(dev->dma, 0, sizeof(*dev->dma));

    for (i = 0; i <= DRM_MAX_ORDER; i++)
        (void) memset(&dev->dma->bufs[i], 0, sizeof(dev->dma->bufs[0]));

    mutex_init(&dev->dma_lock, NULL, MUTEX_DRIVER, NULL);

    return 0;
}

/**
 * Cleanup the DMA resources.
 *
 * \param dev DRM device.
 *
 * Free all pages associated with DMA buffers, the buffers and pages lists, and
 * finally the drm_device::dma structure itself.
 */
void drm_dma_takedown(struct drm_device *dev)
{
    struct drm_device_dma *dma = dev->dma;
    int i, j;

    if (!dma)
        return;

    /* Clear dma buffers */
    for (i = 0; i <= DRM_MAX_ORDER; i++) {
        if (dma->bufs[i].seg_count) {
            DRM_DEBUG("order %d: buf_count = %d,"
                  " seg_count = %d\n",
                  i,
                  dma->bufs[i].buf_count,
                  dma->bufs[i].seg_count);
            kfree(dma->bufs[i].seglist,
                dma->bufs[i].seg_count * sizeof (*dma->bufs[0].seglist));
        }
        if (dma->bufs[i].buf_count) {
            for (j = 0; j < dma->bufs[i].buf_count; j++) {
                if (dma->bufs[i].buflist[j].dev_private) {
                    kfree(dma->bufs[i].buflist[j].dev_private,
                        dma->bufs[i].buflist[j].dev_priv_size);
                }
            }
            kfree(dma->bufs[i].buflist,
                dma->bufs[i].buf_count * sizeof(*dma->bufs[0].buflist));
        }
    }

    if (dma->buflist)
        kfree(dma->buflist, dma->buf_count * sizeof(*dma->buflist));
    if (dma->pagelist)
        kfree(dma->pagelist, dma->page_count * sizeof(*dma->pagelist));
    kfree(dev->dma, sizeof(*dev->dma));
    dev->dma = NULL;

    mutex_destroy(&dev->dma_lock);
}

/**
 * Free a buffer.
 *
 * \param dev DRM device.
 * \param buf buffer to free.
 *
 * Resets the fields of \p buf.
 */
/* LINTED */
void drm_free_buffer(struct drm_device *dev, drm_buf_t *buf)
{
    if (!buf)
        return;

    buf->pending = 0;
    buf->file_priv = NULL;
    buf->used = 0;
}

/**
 * Reclaim the buffers.
 *
 * \param file_priv DRM file private.
 *
 * Frees each buffer associated with \p file_priv not already on the hardware.
 */
void drm_core_reclaim_buffers(struct drm_device *dev,
                  struct drm_file *file_priv)
{
    struct drm_device_dma *dma = dev->dma;
    int i;

    if (!dma)
        return;
    for (i = 0; i < dma->buf_count; i++) {
        if (dma->buflist[i]->file_priv == file_priv) {
            switch (dma->buflist[i]->list) {
            case DRM_LIST_NONE:
                drm_free_buffer(dev, dma->buflist[i]);
                break;
            case DRM_LIST_WAIT:
                dma->buflist[i]->list = DRM_LIST_RECLAIM;
                break;
            default:
                /* Buffer already on hardware. */
                break;
            }
        }
    }
}