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path: root/shared-core/nouveau_fifo.c
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/*
 * Copyright 2005-2006 Stephane Marchesin
 * 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
 * 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.
 */

#include "drmP.h"
#include "drm.h"
#include "nouveau_drv.h"
#include "nouveau_drm.h"


/* returns the size of fifo context */
int nouveau_fifo_ctx_size(struct drm_device *dev)
{
	struct drm_nouveau_private *dev_priv=dev->dev_private;

	if (dev_priv->card_type >= NV_40)
		return 128;
	else if (dev_priv->card_type >= NV_17)
		return 64;
	else
		return 32;
}

/***********************************
 * functions doing the actual work
 ***********************************/

static int nouveau_fifo_instmem_configure(struct drm_device *dev)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;

	NV_WRITE(NV03_PFIFO_RAMHT,
			(0x03 << 24) /* search 128 */ |
			((dev_priv->ramht_bits - 9) << 16) |
			(dev_priv->ramht_offset >> 8)
			);

	NV_WRITE(NV03_PFIFO_RAMRO, dev_priv->ramro_offset>>8);

	switch(dev_priv->card_type)
	{
		case NV_40:
			switch (dev_priv->chipset) {
			case 0x47:
			case 0x49:
			case 0x4b:
				NV_WRITE(0x2230, 1);
				break;
			default:
				break;
			}
			NV_WRITE(NV40_PFIFO_RAMFC, 0x30002);
			break;
		case NV_44:
			NV_WRITE(NV40_PFIFO_RAMFC, ((nouveau_mem_fb_amount(dev)-512*1024+dev_priv->ramfc_offset)>>16) |
					(2 << 16));
			break;
		case NV_30:
		case NV_20:
		case NV_17:
			NV_WRITE(NV03_PFIFO_RAMFC, (dev_priv->ramfc_offset>>8) |
					(1 << 16) /* 64 Bytes entry*/);
			/* XXX nvidia blob set bit 18, 21,23 for nv20 & nv30 */
			break;
		case NV_11:
		case NV_10:
		case NV_04:
			NV_WRITE(NV03_PFIFO_RAMFC, dev_priv->ramfc_offset>>8);
			break;
	}

	return 0;
}

int nouveau_fifo_init(struct drm_device *dev)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	int ret;

	NV_WRITE(NV03_PMC_ENABLE, NV_READ(NV03_PMC_ENABLE) &
			~NV_PMC_ENABLE_PFIFO);
	NV_WRITE(NV03_PMC_ENABLE, NV_READ(NV03_PMC_ENABLE) |
			 NV_PMC_ENABLE_PFIFO);

	/* Enable PFIFO error reporting */
	NV_WRITE(NV03_PFIFO_INTR_0, 0xFFFFFFFF);
	NV_WRITE(NV03_PFIFO_INTR_EN_0, 0xFFFFFFFF);

	NV_WRITE(NV03_PFIFO_CACHES, 0x00000000);

	ret = nouveau_fifo_instmem_configure(dev);
	if (ret) {
		DRM_ERROR("Failed to configure instance memory\n");
		return ret;
	}

	/* FIXME remove all the stuff that's done in nouveau_fifo_alloc */

	DRM_DEBUG("Setting defaults for remaining PFIFO regs\n");

	/* All channels into PIO mode */
	NV_WRITE(NV04_PFIFO_MODE, 0x00000000);

	NV_WRITE(NV03_PFIFO_CACHE1_PUSH0, 0x00000000);
	NV_WRITE(NV04_PFIFO_CACHE1_PULL0, 0x00000000);
	/* Channel 0 active, PIO mode */
	NV_WRITE(NV03_PFIFO_CACHE1_PUSH1, 0x00000000);
	/* PUT and GET to 0 */
	NV_WRITE(NV04_PFIFO_CACHE1_DMA_PUT, 0x00000000);
	NV_WRITE(NV04_PFIFO_CACHE1_DMA_GET, 0x00000000);
	/* No cmdbuf object */
	NV_WRITE(NV04_PFIFO_CACHE1_DMA_INSTANCE, 0x00000000);
	NV_WRITE(NV03_PFIFO_CACHE0_PUSH0, 0x00000000);
	NV_WRITE(NV03_PFIFO_CACHE0_PULL0, 0x00000000);
	NV_WRITE(NV04_PFIFO_SIZE, 0x0000FFFF);
	NV_WRITE(NV04_PFIFO_CACHE1_HASH, 0x0000FFFF);
	NV_WRITE(NV04_PFIFO_CACHE0_PULL1, 0x00000001);
	NV_WRITE(NV04_PFIFO_CACHE1_DMA_CTL, 0x00000000);
	NV_WRITE(NV04_PFIFO_CACHE1_DMA_STATE, 0x00000000);
	NV_WRITE(NV04_PFIFO_CACHE1_ENGINE, 0x00000000);

	NV_WRITE(NV04_PFIFO_CACHE1_DMA_FETCH, NV_PFIFO_CACHE1_DMA_FETCH_TRIG_112_BYTES |
				      NV_PFIFO_CACHE1_DMA_FETCH_SIZE_128_BYTES |
				      NV_PFIFO_CACHE1_DMA_FETCH_MAX_REQS_4 |
#ifdef __BIG_ENDIAN
				      NV_PFIFO_CACHE1_BIG_ENDIAN |
#endif
				      0x00000000);

	NV_WRITE(NV04_PFIFO_CACHE1_DMA_PUSH, 0x00000001);
	NV_WRITE(NV03_PFIFO_CACHE1_PUSH0, 0x00000001);
	NV_WRITE(NV04_PFIFO_CACHE1_PULL0, 0x00000001);
	NV_WRITE(NV04_PFIFO_CACHE1_PULL1, 0x00000001);

	/* FIXME on NV04 */
	if (dev_priv->card_type >= NV_10) {
		NV_WRITE(NV10_PGRAPH_CTX_USER, 0x0);
		NV_WRITE(NV04_PFIFO_DELAY_0, 0xff /* retrycount*/ );
		if (dev_priv->card_type >= NV_40)
			NV_WRITE(NV10_PGRAPH_CTX_CONTROL, 0x00002001);
		else
			NV_WRITE(NV10_PGRAPH_CTX_CONTROL, 0x10110000);
	} else {
		NV_WRITE(NV04_PGRAPH_CTX_USER, 0x0);
		NV_WRITE(NV04_PFIFO_DELAY_0, 0xff /* retrycount*/ );
		NV_WRITE(NV04_PGRAPH_CTX_CONTROL, 0x10110000);
	}

	NV_WRITE(NV04_PFIFO_DMA_TIMESLICE, 0x001fffff);
	NV_WRITE(NV03_PFIFO_CACHES, 0x00000001);
	return 0;
}

static int
nouveau_fifo_pushbuf_ctxdma_init(struct nouveau_channel *chan)
{
	struct drm_device *dev = chan->dev;
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct mem_block *pb = chan->pushbuf_mem;
	struct nouveau_gpuobj *pushbuf = NULL;
	int ret;

	if (pb->flags & NOUVEAU_MEM_AGP) {
		ret = nouveau_gpuobj_gart_dma_new(chan, pb->start, pb->size,
						  NV_DMA_ACCESS_RO,
						  &pushbuf,
						  &chan->pushbuf_base);
	} else
	if (pb->flags & NOUVEAU_MEM_PCI) {
		ret = nouveau_gpuobj_dma_new(chan, NV_CLASS_DMA_IN_MEMORY,
					     pb->start, pb->size,
					     NV_DMA_ACCESS_RO,
					     NV_DMA_TARGET_PCI_NONLINEAR,
					     &pushbuf);
		chan->pushbuf_base = 0;
	} else if (dev_priv->card_type != NV_04) {
		ret = nouveau_gpuobj_dma_new(chan, NV_CLASS_DMA_IN_MEMORY,
					     pb->start, pb->size,
					     NV_DMA_ACCESS_RO,
					     NV_DMA_TARGET_VIDMEM, &pushbuf);
		chan->pushbuf_base = 0;
	} else {
		/* NV04 cmdbuf hack, from original ddx.. not sure of it's
		 * exact reason for existing :)  PCI access to cmdbuf in
		 * VRAM.
		 */
		ret = nouveau_gpuobj_dma_new(chan, NV_CLASS_DMA_IN_MEMORY,
					     pb->start +
					       drm_get_resource_start(dev, 1),
					     pb->size, NV_DMA_ACCESS_RO,
					     NV_DMA_TARGET_PCI, &pushbuf);
		chan->pushbuf_base = 0;
	}

	if ((ret = nouveau_gpuobj_ref_add(dev, chan, 0, pushbuf,
					  &chan->pushbuf))) {
		DRM_ERROR("Error referencing push buffer ctxdma: %d\n", ret);
		if (pushbuf != dev_priv->gart_info.sg_ctxdma)
			nouveau_gpuobj_del(dev, &pushbuf);
		return ret;
	}

	return 0;
}

static struct mem_block *
nouveau_fifo_user_pushbuf_alloc(struct drm_device *dev)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct nouveau_config *config = &dev_priv->config;
	struct mem_block *pb;
	int pb_min_size = max(NV03_FIFO_SIZE,PAGE_SIZE);

	/* Defaults for unconfigured values */
	if (!config->cmdbuf.location)
		config->cmdbuf.location = NOUVEAU_MEM_FB;
	if (!config->cmdbuf.size || config->cmdbuf.size < pb_min_size)
		config->cmdbuf.size = pb_min_size;

	pb = nouveau_mem_alloc(dev, 0, config->cmdbuf.size,
			       config->cmdbuf.location | NOUVEAU_MEM_MAPPED,
			       (struct drm_file *)-2);
	if (!pb)
		DRM_ERROR("Couldn't allocate DMA push buffer.\n");

	return pb;
}

/* allocates and initializes a fifo for user space consumption */
int
nouveau_fifo_alloc(struct drm_device *dev, struct nouveau_channel **chan_ret,
		   struct drm_file *file_priv, struct mem_block *pushbuf,
		   uint32_t vram_handle, uint32_t tt_handle)
{
	int ret;
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct nouveau_engine *engine = &dev_priv->Engine;
	struct nouveau_channel *chan;
	int channel;

	/*
	 * Alright, here is the full story
	 * Nvidia cards have multiple hw fifo contexts (praise them for that,
	 * no complicated crash-prone context switches)
	 * We allocate a new context for each app and let it write to it directly
	 * (woo, full userspace command submission !)
	 * When there are no more contexts, you lost
	 */
	for (channel = 0; channel < engine->fifo.channels; channel++) {
		if (dev_priv->fifos[channel] == NULL)
			break;
	}

	/* no more fifos. you lost. */
	if (channel == engine->fifo.channels)
		return -EINVAL;

	dev_priv->fifos[channel] = drm_calloc(1, sizeof(struct nouveau_channel),
					      DRM_MEM_DRIVER);
	if (!dev_priv->fifos[channel])
		return -ENOMEM;
	dev_priv->fifo_alloc_count++;
	chan = dev_priv->fifos[channel];
	chan->dev = dev;
	chan->id = channel;
	chan->file_priv = file_priv;
	chan->pushbuf_mem = pushbuf;

	DRM_INFO("Allocating FIFO number %d\n", channel);

	/* Locate channel's user control regs */
	if (dev_priv->card_type < NV_40) {
		chan->user = NV03_USER(channel);
		chan->user_size = NV03_USER_SIZE;
		chan->put = NV03_USER_DMA_PUT(channel);
		chan->get = NV03_USER_DMA_GET(channel);
		chan->ref_cnt = NV03_USER_REF_CNT(channel);
	} else
	if (dev_priv->card_type < NV_50) {
		chan->user = NV40_USER(channel);
		chan->user_size = NV40_USER_SIZE;
		chan->put = NV40_USER_DMA_PUT(channel);
		chan->get = NV40_USER_DMA_GET(channel);
		chan->ref_cnt = NV40_USER_REF_CNT(channel);
	} else {
		chan->user = NV50_USER(channel);
		chan->user_size = NV50_USER_SIZE;
		chan->put = NV50_USER_DMA_PUT(channel);
		chan->get = NV50_USER_DMA_GET(channel);
		chan->ref_cnt = NV50_USER_REF_CNT(channel);
	}

	/* Allocate space for per-channel fixed notifier memory */
	ret = nouveau_notifier_init_channel(chan);
	if (ret) {
		nouveau_fifo_free(chan);
		return ret;
	}

	/* Setup channel's default objects */
	ret = nouveau_gpuobj_channel_init(chan, vram_handle, tt_handle);
	if (ret) {
		nouveau_fifo_free(chan);
		return ret;
	}

	/* Create a dma object for the push buffer */
	ret = nouveau_fifo_pushbuf_ctxdma_init(chan);
	if (ret) {
		nouveau_fifo_free(chan);
		return ret;
	}

	nouveau_wait_for_idle(dev);

	/* disable the fifo caches */
	NV_WRITE(NV03_PFIFO_CACHES, 0x00000000);
	NV_WRITE(NV04_PFIFO_CACHE1_DMA_PUSH, NV_READ(NV04_PFIFO_CACHE1_DMA_PUSH)&(~0x1));
	NV_WRITE(NV03_PFIFO_CACHE1_PUSH0, 0x00000000);
	NV_WRITE(NV04_PFIFO_CACHE1_PULL0, 0x00000000);

	/* Create a graphics context for new channel */
	ret = engine->graph.create_context(chan);
	if (ret) {
		nouveau_fifo_free(chan);
		return ret;
	}

	/* Construct inital RAMFC for new channel */
	ret = engine->fifo.create_context(chan);
	if (ret) {
		nouveau_fifo_free(chan);
		return ret;
	}

	/* setup channel's default get/put values
	 * XXX: quite possibly extremely pointless..
	 */
	NV_WRITE(chan->get, chan->pushbuf_base);
	NV_WRITE(chan->put, chan->pushbuf_base);

	/* If this is the first channel, setup PFIFO ourselves.  For any
	 * other case, the GPU will handle this when it switches contexts.
	 */
	if (dev_priv->fifo_alloc_count == 1) {
		ret = engine->fifo.load_context(chan);
		if (ret) {
			nouveau_fifo_free(chan);
			return ret;
		}

		ret = engine->graph.load_context(chan);
		if (ret) {
			nouveau_fifo_free(chan);
			return ret;
		}
	}

	NV_WRITE(NV04_PFIFO_CACHE1_DMA_PUSH,
		 NV_READ(NV04_PFIFO_CACHE1_DMA_PUSH) | 1);
	NV_WRITE(NV03_PFIFO_CACHE1_PUSH0, 0x00000001);
	NV_WRITE(NV04_PFIFO_CACHE1_PULL0, 0x00000001);
	NV_WRITE(NV04_PFIFO_CACHE1_PULL1, 0x00000001);

	/* reenable the fifo caches */
	NV_WRITE(NV03_PFIFO_CACHES, 1);

	DRM_INFO("%s: initialised FIFO %d\n", __func__, channel);
	*chan_ret = chan;
	return 0;
}

static int
nouveau_channel_idle(struct nouveau_channel *chan)
{
	struct drm_device *dev = chan->dev;
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct nouveau_engine *engine = &dev_priv->Engine;
	uint32_t caches;
	int idle;

	caches = NV_READ(NV03_PFIFO_CACHES);
	NV_WRITE(NV03_PFIFO_CACHES, caches & ~1);

	if (engine->fifo.channel_id(dev) != chan->id) {
		struct nouveau_gpuobj *ramfc = chan->ramfc->gpuobj;

		if (INSTANCE_RD(ramfc, 0) != INSTANCE_RD(ramfc, 1))
			idle = 0;
		else
			idle = 1;
	} else {
		idle = (NV_READ(NV04_PFIFO_CACHE1_DMA_GET) ==
			NV_READ(NV04_PFIFO_CACHE1_DMA_PUT));
	}

	NV_WRITE(NV03_PFIFO_CACHES, caches);
	return idle;
}

/* stops a fifo */
void nouveau_fifo_free(struct nouveau_channel *chan)
{
	struct drm_device *dev = chan->dev;
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct nouveau_engine *engine = &dev_priv->Engine;
	uint64_t t_start;

	DRM_INFO("%s: freeing fifo %d\n", __func__, chan->id);

	/* Give the channel a chance to idle, wait 2s (hopefully) */
	t_start = engine->timer.read(dev);
	while (!nouveau_channel_idle(chan)) {
		if (engine->timer.read(dev) - t_start > 2000000000ULL) {
			DRM_ERROR("Failed to idle channel %d before destroy."
				  "Prepare for strangeness..\n", chan->id);
			break;
		}
	}

	/*XXX: Maybe should wait for PGRAPH to finish with the stuff it fetched
	 *     from CACHE1 too?
	 */

	/* disable the fifo caches */
	NV_WRITE(NV03_PFIFO_CACHES, 0x00000000);
	NV_WRITE(NV04_PFIFO_CACHE1_DMA_PUSH, NV_READ(NV04_PFIFO_CACHE1_DMA_PUSH)&(~0x1));
	NV_WRITE(NV03_PFIFO_CACHE1_PUSH0, 0x00000000);
	NV_WRITE(NV04_PFIFO_CACHE1_PULL0, 0x00000000);

	// FIXME XXX needs more code

	engine->fifo.destroy_context(chan);

	/* Cleanup PGRAPH state */
	engine->graph.destroy_context(chan);

	/* reenable the fifo caches */
	NV_WRITE(NV04_PFIFO_CACHE1_DMA_PUSH,
		 NV_READ(NV04_PFIFO_CACHE1_DMA_PUSH) | 1);
	NV_WRITE(NV03_PFIFO_CACHE1_PUSH0, 0x00000001);
	NV_WRITE(NV04_PFIFO_CACHE1_PULL0, 0x00000001);
	NV_WRITE(NV03_PFIFO_CACHES, 0x00000001);

	/* Deallocate push buffer */
	nouveau_gpuobj_ref_del(dev, &chan->pushbuf);
	if (chan->pushbuf_mem) {
		nouveau_mem_free(dev, chan->pushbuf_mem);
		chan->pushbuf_mem = NULL;
	}

	/* Destroy objects belonging to the channel */
	nouveau_gpuobj_channel_takedown(chan);

	nouveau_notifier_takedown_channel(chan);

	dev_priv->fifos[chan->id] = NULL;
	dev_priv->fifo_alloc_count--;
	drm_free(chan, sizeof(*chan), DRM_MEM_DRIVER);
}

/* cleanups all the fifos from file_priv */
void nouveau_fifo_cleanup(struct drm_device *dev, struct drm_file *file_priv)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct nouveau_engine *engine = &dev_priv->Engine;
	int i;

	DRM_DEBUG("clearing FIFO enables from file_priv\n");
	for(i = 0; i < engine->fifo.channels; i++) {
		struct nouveau_channel *chan = dev_priv->fifos[i];

		if (chan && chan->file_priv == file_priv)
			nouveau_fifo_free(chan);
	}
}

int
nouveau_fifo_owner(struct drm_device *dev, struct drm_file *file_priv,
		   int channel)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct nouveau_engine *engine = &dev_priv->Engine;

	if (channel >= engine->fifo.channels)
		return 0;
	if (dev_priv->fifos[channel] == NULL)
		return 0;
	return (dev_priv->fifos[channel]->file_priv == file_priv);
}

/***********************************
 * ioctls wrapping the functions
 ***********************************/

static int nouveau_ioctl_fifo_alloc(struct drm_device *dev, void *data,
				    struct drm_file *file_priv)
{
	struct drm_nouveau_private *dev_priv = dev->dev_private;
	struct drm_nouveau_channel_alloc *init = data;
	struct drm_map_list *entry;
	struct nouveau_channel *chan;
	struct mem_block *pushbuf;
	int res;

	NOUVEAU_CHECK_INITIALISED_WITH_RETURN;

	if (init->fb_ctxdma_handle == ~0 || init->tt_ctxdma_handle == ~0)
		return -EINVAL;

	pushbuf = nouveau_fifo_user_pushbuf_alloc(dev);
	if (!pushbuf)
		return -ENOMEM;

	res = nouveau_fifo_alloc(dev, &chan, file_priv, pushbuf,
				 init->fb_ctxdma_handle,
				 init->tt_ctxdma_handle);
	if (res)
		return res;
	init->channel  = chan->id;
	init->put_base = chan->pushbuf_base;

	/* make the fifo available to user space */
	/* first, the fifo control regs */
	init->ctrl = dev_priv->mmio->offset + chan->user;
	init->ctrl_size = chan->user_size;
	res = drm_addmap(dev, init->ctrl, init->ctrl_size, _DRM_REGISTERS,
			 0, &chan->regs);
	if (res != 0)
		return res;

	entry = drm_find_matching_map(dev, chan->regs);
	if (!entry)
		return -EINVAL;
	init->ctrl = entry->user_token;

	/* pass back FIFO map info to the caller */
	init->cmdbuf      = chan->pushbuf_mem->map_handle;
	init->cmdbuf_size = chan->pushbuf_mem->size;

	/* and the notifier block */
	init->notifier      = chan->notifier_block->map_handle;
	init->notifier_size = chan->notifier_block->size;

	return 0;
}

static int nouveau_ioctl_fifo_free(struct drm_device *dev, void *data,
				   struct drm_file *file_priv)
{
	struct drm_nouveau_channel_free *cfree = data;
	struct nouveau_channel *chan;

	NOUVEAU_CHECK_INITIALISED_WITH_RETURN;
	NOUVEAU_GET_USER_CHANNEL_WITH_RETURN(cfree->channel, file_priv, chan);

	nouveau_fifo_free(chan);
	return 0;
}

/***********************************
 * finally, the ioctl table
 ***********************************/

struct drm_ioctl_desc nouveau_ioctls[] = {
	DRM_IOCTL_DEF(DRM_NOUVEAU_CARD_INIT, nouveau_ioctl_card_init, DRM_AUTH),
	DRM_IOCTL_DEF(DRM_NOUVEAU_GETPARAM, nouveau_ioctl_getparam, DRM_AUTH),
	DRM_IOCTL_DEF(DRM_NOUVEAU_SETPARAM, nouveau_ioctl_setparam, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
	DRM_IOCTL_DEF(DRM_NOUVEAU_CHANNEL_ALLOC, nouveau_ioctl_fifo_alloc, DRM_AUTH),
	DRM_IOCTL_DEF(DRM_NOUVEAU_CHANNEL_FREE, nouveau_ioctl_fifo_free, DRM_AUTH),
	DRM_IOCTL_DEF(DRM_NOUVEAU_GROBJ_ALLOC, nouveau_ioctl_grobj_alloc, DRM_AUTH),
	DRM_IOCTL_DEF(DRM_NOUVEAU_NOTIFIEROBJ_ALLOC, nouveau_ioctl_notifier_alloc, DRM_AUTH),
	DRM_IOCTL_DEF(DRM_NOUVEAU_GPUOBJ_FREE, nouveau_ioctl_gpuobj_free, DRM_AUTH),
	DRM_IOCTL_DEF(DRM_NOUVEAU_MEM_ALLOC, nouveau_ioctl_mem_alloc, DRM_AUTH),
	DRM_IOCTL_DEF(DRM_NOUVEAU_MEM_FREE, nouveau_ioctl_mem_free, DRM_AUTH),
};

int nouveau_max_ioctl = DRM_ARRAY_SIZE(nouveau_ioctls);
id='n2463' href='#n2463'>2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487 2488 2489 2490 2491 2492 2493 2494 2495 2496 2497 2498 2499 2500 2501 2502 2503 2504 2505 2506 2507 2508 2509 2510 2511 2512 2513 2514 2515 2516 2517 2518 2519 2520 2521 2522 2523 2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551 2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571 2572 2573 2574 2575
/**
 * \file xf86drm.c 
 * User-level interface to DRM device
 *
 * \author Rickard E. (Rik) Faith <faith@valinux.com>
 * \author Kevin E. Martin <martin@valinux.com>
 */

/*
 * Copyright 1999 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
 * 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.
 */

#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <strings.h>
#include <ctype.h>
#include <fcntl.h>
#include <errno.h>
#include <signal.h>
#include <time.h>
#include <sys/types.h>
#include <sys/stat.h>
#define stat_t struct stat
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <stdarg.h>

/* Not all systems have MAP_FAILED defined */
#ifndef MAP_FAILED
#define MAP_FAILED ((void *)-1)
#endif

#include "xf86drm.h"

#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
#define DRM_MAJOR 145
#endif

#ifdef __NetBSD__
#define DRM_MAJOR 34
#endif

# ifdef __OpenBSD__
#  define DRM_MAJOR 81
# endif

#ifndef DRM_MAJOR
#define DRM_MAJOR 226		/* Linux */
#endif

/*
 * This definition needs to be changed on some systems if dev_t is a structure.
 * If there is a header file we can get it from, there would be best.
 */
#ifndef makedev
#define makedev(x,y)    ((dev_t)(((x) << 8) | (y)))
#endif

#define DRM_MSG_VERBOSITY 3

#define DRM_NODE_CONTROL 0
#define DRM_NODE_RENDER 1

static drmServerInfoPtr drm_server_info;

void drmSetServerInfo(drmServerInfoPtr info)
{
    drm_server_info = info;
}

/**
 * Output a message to stderr.
 *
 * \param format printf() like format string.
 *
 * \internal
 * This function is a wrapper around vfprintf().
 */

static int drmDebugPrint(const char *format, va_list ap)
{
    return vfprintf(stderr, format, ap);
}

static int (*drm_debug_print)(const char *format, va_list ap) = drmDebugPrint;

void
drmMsg(const char *format, ...)
{
    va_list	ap;
    const char *env;
    if (((env = getenv("LIBGL_DEBUG")) && strstr(env, "verbose")) || drm_server_info)
    {
	va_start(ap, format);
	if (drm_server_info) {
	  drm_server_info->debug_print(format,ap);
	} else {
	  drm_debug_print(format, ap);
	}
	va_end(ap);
    }
}

void
drmSetDebugMsgFunction(int (*debug_msg_ptr)(const char *format, va_list ap))
{
    drm_debug_print = debug_msg_ptr;
}

static void *drmHashTable = NULL; /* Context switch callbacks */

void *drmGetHashTable(void)
{
    return drmHashTable;
}

void *drmMalloc(int size)
{
    void *pt;
    if ((pt = malloc(size)))
	memset(pt, 0, size);
    return pt;
}

void drmFree(void *pt)
{
    if (pt)
	free(pt);
}

/**
 * Call ioctl, restarting if it is interupted
 */
int
drmIoctl(int fd, unsigned long request, void *arg)
{
    int	ret;

    do {
	ret = ioctl(fd, request, arg);
    } while (ret == -1 && (errno == EINTR || errno == EAGAIN));
    return ret;
}

static unsigned long drmGetKeyFromFd(int fd)
{
    stat_t     st;

    st.st_rdev = 0;
    fstat(fd, &st);
    return st.st_rdev;
}

drmHashEntry *drmGetEntry(int fd)
{
    unsigned long key = drmGetKeyFromFd(fd);
    void          *value;
    drmHashEntry  *entry;

    if (!drmHashTable)
	drmHashTable = drmHashCreate();

    if (drmHashLookup(drmHashTable, key, &value)) {
	entry           = drmMalloc(sizeof(*entry));
	entry->fd       = fd;
	entry->f        = NULL;
	entry->tagTable = drmHashCreate();
	drmHashInsert(drmHashTable, key, entry);
    } else {
	entry = value;
    }
    return entry;
}

/**
 * Compare two busid strings
 *
 * \param first
 * \param second
 *
 * \return 1 if matched.
 *
 * \internal
 * This function compares two bus ID strings.  It understands the older
 * PCI:b:d:f format and the newer pci:oooo:bb:dd.f format.  In the format, o is
 * domain, b is bus, d is device, f is function.
 */
static int drmMatchBusID(const char *id1, const char *id2, int pci_domain_ok)
{
    /* First, check if the IDs are exactly the same */
    if (strcasecmp(id1, id2) == 0)
	return 1;

    /* Try to match old/new-style PCI bus IDs. */
    if (strncasecmp(id1, "pci", 3) == 0) {
	unsigned int o1, b1, d1, f1;
	unsigned int o2, b2, d2, f2;
	int ret;

	ret = sscanf(id1, "pci:%04x:%02x:%02x.%u", &o1, &b1, &d1, &f1);
	if (ret != 4) {
	    o1 = 0;
	    ret = sscanf(id1, "PCI:%u:%u:%u", &b1, &d1, &f1);
	    if (ret != 3)
		return 0;
	}

	ret = sscanf(id2, "pci:%04x:%02x:%02x.%u", &o2, &b2, &d2, &f2);
	if (ret != 4) {
	    o2 = 0;
	    ret = sscanf(id2, "PCI:%u:%u:%u", &b2, &d2, &f2);
	    if (ret != 3)
		return 0;
	}

	/* If domains aren't properly supported by the kernel interface,
	 * just ignore them, which sucks less than picking a totally random
	 * card with "open by name"
	 */
	if (!pci_domain_ok)
		o1 = o2 = 0;

	if ((o1 != o2) || (b1 != b2) || (d1 != d2) || (f1 != f2))
	    return 0;
	else
	    return 1;
    }
    return 0;
}

/**
 * Handles error checking for chown call.
 *
 * \param path to file.
 * \param id of the new owner.
 * \param id of the new group.
 *
 * \return zero if success or -1 if failure.
 *
 * \internal
 * Checks for failure. If failure was caused by signal call chown again.
 * If any other failure happened then it will output error mesage using
 * drmMsg() call.
 */
static int chown_check_return(const char *path, uid_t owner, gid_t group)
{
	int rv;

	do {
		rv = chown(path, owner, group);
	} while (rv != 0 && errno == EINTR);

	if (rv == 0)
		return 0;

	drmMsg("Failed to change owner or group for file %s! %d: %s\n",
			path, errno, strerror(errno));
	return -1;
}

/**
 * Open the DRM device, creating it if necessary.
 *
 * \param dev major and minor numbers of the device.
 * \param minor minor number of the device.
 * 
 * \return a file descriptor on success, or a negative value on error.
 *
 * \internal
 * Assembles the device name from \p minor and opens it, creating the device
 * special file node with the major and minor numbers specified by \p dev and
 * parent directory if necessary and was called by root.
 */
static int drmOpenDevice(long dev, int minor, int type)
{
    stat_t          st;
    char            buf[64];
    int             fd;
    mode_t          devmode = DRM_DEV_MODE, serv_mode;
    int             isroot  = !geteuid();
    uid_t           user    = DRM_DEV_UID;
    gid_t           group   = DRM_DEV_GID, serv_group;
    
    sprintf(buf, type ? DRM_DEV_NAME : DRM_CONTROL_DEV_NAME, DRM_DIR_NAME, minor);
    drmMsg("drmOpenDevice: node name is %s\n", buf);

    if (drm_server_info) {
	drm_server_info->get_perms(&serv_group, &serv_mode);
	devmode  = serv_mode ? serv_mode : DRM_DEV_MODE;
	devmode &= ~(S_IXUSR|S_IXGRP|S_IXOTH);
	group = (serv_group >= 0) ? serv_group : DRM_DEV_GID;
    }

#if !defined(UDEV)
    if (stat(DRM_DIR_NAME, &st)) {
	if (!isroot)
	    return DRM_ERR_NOT_ROOT;
	mkdir(DRM_DIR_NAME, DRM_DEV_DIRMODE);
	chown_check_return(DRM_DIR_NAME, 0, 0); /* root:root */
	chmod(DRM_DIR_NAME, DRM_DEV_DIRMODE);
    }

    /* Check if the device node exists and create it if necessary. */
    if (stat(buf, &st)) {
	if (!isroot)
	    return DRM_ERR_NOT_ROOT;
	remove(buf);
	mknod(buf, S_IFCHR | devmode, dev);
    }

    if (drm_server_info) {
	chown_check_return(buf, user, group);
	chmod(buf, devmode);
    }
#else
    /* if we modprobed then wait for udev */
    {
	int udev_count = 0;
wait_for_udev:
        if (stat(DRM_DIR_NAME, &st)) {
		usleep(20);
		udev_count++;

		if (udev_count == 50)
			return -1;
		goto wait_for_udev;
	}

    	if (stat(buf, &st)) {
		usleep(20);
		udev_count++;

		if (udev_count == 50)
			return -1;
		goto wait_for_udev;
    	}
    }
#endif

    fd = open(buf, O_RDWR, 0);
    drmMsg("drmOpenDevice: open result is %d, (%s)\n",
		fd, fd < 0 ? strerror(errno) : "OK");
    if (fd >= 0)
	return fd;

#if !defined(UDEV)
    /* Check if the device node is not what we expect it to be, and recreate it
     * and try again if so.
     */
    if (st.st_rdev != dev) {
	if (!isroot)
	    return DRM_ERR_NOT_ROOT;
	remove(buf);
	mknod(buf, S_IFCHR | devmode, dev);
	if (drm_server_info) {
	    chown_check_return(buf, user, group);
	    chmod(buf, devmode);
	}
    }
    fd = open(buf, O_RDWR, 0);
    drmMsg("drmOpenDevice: open result is %d, (%s)\n",
		fd, fd < 0 ? strerror(errno) : "OK");
    if (fd >= 0)
	return fd;

    drmMsg("drmOpenDevice: Open failed\n");
    remove(buf);
#endif
    return -errno;
}


/**
 * Open the DRM device
 *
 * \param minor device minor number.
 * \param create allow to create the device if set.
 *
 * \return a file descriptor on success, or a negative value on error.
 * 
 * \internal
 * Calls drmOpenDevice() if \p create is set, otherwise assembles the device
 * name from \p minor and opens it.
 */
static int drmOpenMinor(int minor, int create, int type)
{
    int  fd;
    char buf[64];
    
    if (create)
	return drmOpenDevice(makedev(DRM_MAJOR, minor), minor, type);
    
    sprintf(buf, type ? DRM_DEV_NAME : DRM_CONTROL_DEV_NAME, DRM_DIR_NAME, minor);
    if ((fd = open(buf, O_RDWR, 0)) >= 0)
	return fd;
    return -errno;
}


/**
 * Determine whether the DRM kernel driver has been loaded.
 * 
 * \return 1 if the DRM driver is loaded, 0 otherwise.
 *
 * \internal 
 * Determine the presence of the kernel driver by attempting to open the 0
 * minor and get version information.  For backward compatibility with older
 * Linux implementations, /proc/dri is also checked.
 */
int drmAvailable(void)
{
    drmVersionPtr version;
    int           retval = 0;
    int           fd;

    if ((fd = drmOpenMinor(0, 1, DRM_NODE_RENDER)) < 0) {
#ifdef __linux__
	/* Try proc for backward Linux compatibility */
	if (!access("/proc/dri/0", R_OK))
	    return 1;
#endif
	return 0;
    }
    
    if ((version = drmGetVersion(fd))) {
	retval = 1;
	drmFreeVersion(version);
    }
    close(fd);

    return retval;
}


/**
 * Open the device by bus ID.
 *
 * \param busid bus ID.
 *
 * \return a file descriptor on success, or a negative value on error.
 *
 * \internal
 * This function attempts to open every possible minor (up to DRM_MAX_MINOR),
 * comparing the device bus ID with the one supplied.
 *
 * \sa drmOpenMinor() and drmGetBusid().
 */
static int drmOpenByBusid(const char *busid)
{
    int        i, pci_domain_ok = 1;
    int        fd;
    const char *buf;
    drmSetVersion sv;

    drmMsg("drmOpenByBusid: Searching for BusID %s\n", busid);
    for (i = 0; i < DRM_MAX_MINOR; i++) {
	fd = drmOpenMinor(i, 1, DRM_NODE_RENDER);
	drmMsg("drmOpenByBusid: drmOpenMinor returns %d\n", fd);
	if (fd >= 0) {
	    /* We need to try for 1.4 first for proper PCI domain support
	     * and if that fails, we know the kernel is busted
	     */
	    sv.drm_di_major = 1;
	    sv.drm_di_minor = 4;
	    sv.drm_dd_major = -1;	/* Don't care */
	    sv.drm_dd_minor = -1;	/* Don't care */
	    if (drmSetInterfaceVersion(fd, &sv)) {
#ifndef __alpha__
		pci_domain_ok = 0;
#endif
		sv.drm_di_major = 1;
		sv.drm_di_minor = 1;
		sv.drm_dd_major = -1;       /* Don't care */
		sv.drm_dd_minor = -1;       /* Don't care */
		drmMsg("drmOpenByBusid: Interface 1.4 failed, trying 1.1\n",fd);
		drmSetInterfaceVersion(fd, &sv);
	    }
	    buf = drmGetBusid(fd);
	    drmMsg("drmOpenByBusid: drmGetBusid reports %s\n", buf);
	    if (buf && drmMatchBusID(buf, busid, pci_domain_ok)) {
		drmFreeBusid(buf);
		return fd;
	    }
	    if (buf)
		drmFreeBusid(buf);
	    close(fd);
	}
    }
    return -1;
}


/**
 * Open the device by name.
 *
 * \param name driver name.
 * 
 * \return a file descriptor on success, or a negative value on error.
 * 
 * \internal
 * This function opens the first minor number that matches the driver name and
 * isn't already in use.  If it's in use it then it will already have a bus ID
 * assigned.
 * 
 * \sa drmOpenMinor(), drmGetVersion() and drmGetBusid().
 */
static int drmOpenByName(const char *name)
{
    int           i;
    int           fd;
    drmVersionPtr version;
    char *        id;
    
    if (!drmAvailable()) {
	if (!drm_server_info) {
	    return -1;
	}
	else {
	    /* try to load the kernel module now */
	    if (!drm_server_info->load_module(name)) {
		drmMsg("[drm] failed to load kernel module \"%s\"\n", name);
		return -1;
	    }
	}
    }

    /*
     * Open the first minor number that matches the driver name and isn't
     * already in use.  If it's in use it will have a busid assigned already.
     */
    for (i = 0; i < DRM_MAX_MINOR; i++) {
	if ((fd = drmOpenMinor(i, 1, DRM_NODE_RENDER)) >= 0) {
	    if ((version = drmGetVersion(fd))) {
		if (!strcmp(version->name, name)) {
		    drmFreeVersion(version);
		    id = drmGetBusid(fd);
		    drmMsg("drmGetBusid returned '%s'\n", id ? id : "NULL");
		    if (!id || !*id) {
			if (id)
			    drmFreeBusid(id);
			return fd;
		    } else {
			drmFreeBusid(id);
		    }
		} else {
		    drmFreeVersion(version);
		}
	    }
	    close(fd);
	}
    }

#ifdef __linux__
    /* Backward-compatibility /proc support */
    for (i = 0; i < 8; i++) {
	char proc_name[64], buf[512];
	char *driver, *pt, *devstring;
	int  retcode;
	
	sprintf(proc_name, "/proc/dri/%d/name", i);
	if ((fd = open(proc_name, 0, 0)) >= 0) {
	    retcode = read(fd, buf, sizeof(buf)-1);
	    close(fd);
	    if (retcode) {
		buf[retcode-1] = '\0';
		for (driver = pt = buf; *pt && *pt != ' '; ++pt)
		    ;
		if (*pt) { /* Device is next */
		    *pt = '\0';
		    if (!strcmp(driver, name)) { /* Match */
			for (devstring = ++pt; *pt && *pt != ' '; ++pt)
			    ;
			if (*pt) { /* Found busid */
			    return drmOpenByBusid(++pt);
			} else { /* No busid */
			    return drmOpenDevice(strtol(devstring, NULL, 0),i, DRM_NODE_RENDER);
			}
		    }
		}
	    }
	}
    }
#endif

    return -1;
}


/**
 * Open the DRM device.
 *
 * Looks up the specified name and bus ID, and opens the device found.  The
 * entry in /dev/dri is created if necessary and if called by root.
 *
 * \param name driver name. Not referenced if bus ID is supplied.
 * \param busid bus ID. Zero if not known.
 * 
 * \return a file descriptor on success, or a negative value on error.
 * 
 * \internal
 * It calls drmOpenByBusid() if \p busid is specified or drmOpenByName()
 * otherwise.
 */
int drmOpen(const char *name, const char *busid)
{
    if (!drmAvailable() && name != NULL && drm_server_info) {
	/* try to load the kernel */
	if (!drm_server_info->load_module(name)) {
	    drmMsg("[drm] failed to load kernel module \"%s\"\n", name);
	    return -1;
	}
    }

    if (busid) {
	int fd = drmOpenByBusid(busid);
	if (fd >= 0)
	    return fd;
    }
    
    if (name)
	return drmOpenByName(name);

    return -1;
}

int drmOpenControl(int minor)
{
    return drmOpenMinor(minor, 0, DRM_NODE_CONTROL);
}

/**
 * Free the version information returned by drmGetVersion().
 *
 * \param v pointer to the version information.
 *
 * \internal
 * It frees the memory pointed by \p %v as well as all the non-null strings
 * pointers in it.
 */
void drmFreeVersion(drmVersionPtr v)
{
    if (!v)
	return;
    drmFree(v->name);
    drmFree(v->date);
    drmFree(v->desc);
    drmFree(v);
}


/**
 * Free the non-public version information returned by the kernel.
 *
 * \param v pointer to the version information.
 *
 * \internal
 * Used by drmGetVersion() to free the memory pointed by \p %v as well as all
 * the non-null strings pointers in it.
 */
static void drmFreeKernelVersion(drm_version_t *v)
{
    if (!v)
	return;
    drmFree(v->name);
    drmFree(v->date);
    drmFree(v->desc);
    drmFree(v);
}


/**
 * Copy version information.
 * 
 * \param d destination pointer.
 * \param s source pointer.
 * 
 * \internal
 * Used by drmGetVersion() to translate the information returned by the ioctl
 * interface in a private structure into the public structure counterpart.
 */
static void drmCopyVersion(drmVersionPtr d, const drm_version_t *s)
{
    d->version_major      = s->version_major;
    d->version_minor      = s->version_minor;
    d->version_patchlevel = s->version_patchlevel;
    d->name_len           = s->name_len;
    d->name               = strdup(s->name);
    d->date_len           = s->date_len;
    d->date               = strdup(s->date);
    d->desc_len           = s->desc_len;
    d->desc               = strdup(s->desc);
}


/**
 * Query the driver version information.
 *
 * \param fd file descriptor.
 * 
 * \return pointer to a drmVersion structure which should be freed with
 * drmFreeVersion().
 * 
 * \note Similar information is available via /proc/dri.
 * 
 * \internal
 * It gets the version information via successive DRM_IOCTL_VERSION ioctls,
 * first with zeros to get the string lengths, and then the actually strings.
 * It also null-terminates them since they might not be already.
 */
drmVersionPtr drmGetVersion(int fd)
{
    drmVersionPtr retval;
    drm_version_t *version = drmMalloc(sizeof(*version));

    version->name_len    = 0;
    version->name        = NULL;
    version->date_len    = 0;
    version->date        = NULL;
    version->desc_len    = 0;
    version->desc        = NULL;

    if (drmIoctl(fd, DRM_IOCTL_VERSION, version)) {
	drmFreeKernelVersion(version);
	return NULL;
    }

    if (version->name_len)
	version->name    = drmMalloc(version->name_len + 1);
    if (version->date_len)
	version->date    = drmMalloc(version->date_len + 1);
    if (version->desc_len)
	version->desc    = drmMalloc(version->desc_len + 1);

    if (drmIoctl(fd, DRM_IOCTL_VERSION, version)) {
	drmMsg("DRM_IOCTL_VERSION: %s\n", strerror(errno));
	drmFreeKernelVersion(version);
	return NULL;
    }

    /* The results might not be null-terminated strings, so terminate them. */
    if (version->name_len) version->name[version->name_len] = '\0';
    if (version->date_len) version->date[version->date_len] = '\0';
    if (version->desc_len) version->desc[version->desc_len] = '\0';

    retval = drmMalloc(sizeof(*retval));
    drmCopyVersion(retval, version);
    drmFreeKernelVersion(version);
    return retval;
}


/**
 * Get version information for the DRM user space library.
 * 
 * This version number is driver independent.
 * 
 * \param fd file descriptor.
 *
 * \return version information.
 * 
 * \internal
 * This function allocates and fills a drm_version structure with a hard coded
 * version number.
 */
drmVersionPtr drmGetLibVersion(int fd)
{
    drm_version_t *version = drmMalloc(sizeof(*version));

    /* Version history:
     *   NOTE THIS MUST NOT GO ABOVE VERSION 1.X due to drivers needing it
     *   revision 1.0.x = original DRM interface with no drmGetLibVersion
     *                    entry point and many drm<Device> extensions
     *   revision 1.1.x = added drmCommand entry points for device extensions
     *                    added drmGetLibVersion to identify libdrm.a version
     *   revision 1.2.x = added drmSetInterfaceVersion
     *                    modified drmOpen to handle both busid and name
     *   revision 1.3.x = added server + memory manager
     */
    version->version_major      = 1;
    version->version_minor      = 3;
    version->version_patchlevel = 0;

    return (drmVersionPtr)version;
}

int drmGetCap(int fd, uint64_t capability, uint64_t *value)
{
	struct drm_get_cap cap = { capability, 0 };
	int ret;

	ret = drmIoctl(fd, DRM_IOCTL_GET_CAP, &cap);
	if (ret)
		return ret;

	*value = cap.value;
	return 0;
}

/**
 * Free the bus ID information.
 *
 * \param busid bus ID information string as given by drmGetBusid().
 *
 * \internal
 * This function is just frees the memory pointed by \p busid.
 */
void drmFreeBusid(const char *busid)
{
    drmFree((void *)busid);
}


/**
 * Get the bus ID of the device.
 *
 * \param fd file descriptor.
 *
 * \return bus ID string.
 *
 * \internal
 * This function gets the bus ID via successive DRM_IOCTL_GET_UNIQUE ioctls to
 * get the string length and data, passing the arguments in a drm_unique
 * structure.
 */
char *drmGetBusid(int fd)
{
    drm_unique_t u;

    u.unique_len = 0;
    u.unique     = NULL;

    if (drmIoctl(fd, DRM_IOCTL_GET_UNIQUE, &u))
	return NULL;
    u.unique = drmMalloc(u.unique_len + 1);
    if (drmIoctl(fd, DRM_IOCTL_GET_UNIQUE, &u))
	return NULL;
    u.unique[u.unique_len] = '\0';

    return u.unique;
}


/**
 * Set the bus ID of the device.
 *
 * \param fd file descriptor.
 * \param busid bus ID string.
 *
 * \return zero on success, negative on failure.
 *
 * \internal
 * This function is a wrapper around the DRM_IOCTL_SET_UNIQUE ioctl, passing
 * the arguments in a drm_unique structure.
 */
int drmSetBusid(int fd, const char *busid)
{
    drm_unique_t u;

    u.unique     = (char *)busid;
    u.unique_len = strlen(busid);

    if (drmIoctl(fd, DRM_IOCTL_SET_UNIQUE, &u)) {
	return -errno;
    }
    return 0;
}

int drmGetMagic(int fd, drm_magic_t * magic)
{
    drm_auth_t auth;

    *magic = 0;
    if (drmIoctl(fd, DRM_IOCTL_GET_MAGIC, &auth))
	return -errno;
    *magic = auth.magic;
    return 0;
}

int drmAuthMagic(int fd, drm_magic_t magic)
{
    drm_auth_t auth;

    auth.magic = magic;
    if (drmIoctl(fd, DRM_IOCTL_AUTH_MAGIC, &auth))
	return -errno;
    return 0;
}

/**
 * Specifies a range of memory that is available for mapping by a
 * non-root process.
 *
 * \param fd file descriptor.
 * \param offset usually the physical address. The actual meaning depends of
 * the \p type parameter. See below.
 * \param size of the memory in bytes.
 * \param type type of the memory to be mapped.
 * \param flags combination of several flags to modify the function actions.
 * \param handle will be set to a value that may be used as the offset
 * parameter for mmap().
 * 
 * \return zero on success or a negative value on error.
 *
 * \par Mapping the frame buffer
 * For the frame buffer
 * - \p offset will be the physical address of the start of the frame buffer,
 * - \p size will be the size of the frame buffer in bytes, and
 * - \p type will be DRM_FRAME_BUFFER.
 *
 * \par
 * The area mapped will be uncached. If MTRR support is available in the
 * kernel, the frame buffer area will be set to write combining. 
 *
 * \par Mapping the MMIO register area
 * For the MMIO register area,
 * - \p offset will be the physical address of the start of the register area,
 * - \p size will be the size of the register area bytes, and
 * - \p type will be DRM_REGISTERS.
 * \par
 * The area mapped will be uncached. 
 * 
 * \par Mapping the SAREA
 * For the SAREA,
 * - \p offset will be ignored and should be set to zero,
 * - \p size will be the desired size of the SAREA in bytes,
 * - \p type will be DRM_SHM.
 * 
 * \par
 * A shared memory area of the requested size will be created and locked in
 * kernel memory. This area may be mapped into client-space by using the handle
 * returned. 
 * 
 * \note May only be called by root.
 *
 * \internal
 * This function is a wrapper around the DRM_IOCTL_ADD_MAP ioctl, passing
 * the arguments in a drm_map structure.
 */
int drmAddMap(int fd, drm_handle_t offset, drmSize size, drmMapType type,
	      drmMapFlags flags, drm_handle_t *handle)
{
    drm_map_t map;

    map.offset  = offset;
    map.size    = size;
    map.handle  = 0;
    map.type    = type;
    map.flags   = flags;
    if (drmIoctl(fd, DRM_IOCTL_ADD_MAP, &map))
	return -errno;
    if (handle)
	*handle = (drm_handle_t)(uintptr_t)map.handle;
    return 0;
}

int drmRmMap(int fd, drm_handle_t handle)
{
    drm_map_t map;

    map.handle = (void *)(uintptr_t)handle;

    if(drmIoctl(fd, DRM_IOCTL_RM_MAP, &map))
	return -errno;
    return 0;
}

/**
 * Make buffers available for DMA transfers.
 * 
 * \param fd file descriptor.
 * \param count number of buffers.
 * \param size size of each buffer.
 * \param flags buffer allocation flags.
 * \param agp_offset offset in the AGP aperture 
 *
 * \return number of buffers allocated, negative on error.
 *
 * \internal
 * This function is a wrapper around DRM_IOCTL_ADD_BUFS ioctl.
 *
 * \sa drm_buf_desc.
 */
int drmAddBufs(int fd, int count, int size, drmBufDescFlags flags,
	       int agp_offset)
{
    drm_buf_desc_t request;

    request.count     = count;
    request.size      = size;
    request.low_mark  = 0;
    request.high_mark = 0;
    request.flags     = flags;
    request.agp_start = agp_offset;

    if (drmIoctl(fd, DRM_IOCTL_ADD_BUFS, &request))
	return -errno;
    return request.count;
}

int drmMarkBufs(int fd, double low, double high)
{
    drm_buf_info_t info;
    int            i;

    info.count = 0;
    info.list  = NULL;

    if (drmIoctl(fd, DRM_IOCTL_INFO_BUFS, &info))
	return -EINVAL;

    if (!info.count)
	return -EINVAL;

    if (!(info.list = drmMalloc(info.count * sizeof(*info.list))))
	return -ENOMEM;

    if (drmIoctl(fd, DRM_IOCTL_INFO_BUFS, &info)) {
	int retval = -errno;
	drmFree(info.list);
	return retval;
    }

    for (i = 0; i < info.count; i++) {
	info.list[i].low_mark  = low  * info.list[i].count;
	info.list[i].high_mark = high * info.list[i].count;
	if (drmIoctl(fd, DRM_IOCTL_MARK_BUFS, &info.list[i])) {
	    int retval = -errno;
	    drmFree(info.list);
	    return retval;
	}
    }
    drmFree(info.list);

    return 0;
}

/**
 * Free buffers.
 *
 * \param fd file descriptor.
 * \param count number of buffers to free.
 * \param list list of buffers to be freed.
 *
 * \return zero on success, or a negative value on failure.
 * 
 * \note This function is primarily used for debugging.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_FREE_BUFS ioctl, passing
 * the arguments in a drm_buf_free structure.
 */
int drmFreeBufs(int fd, int count, int *list)
{
    drm_buf_free_t request;

    request.count = count;
    request.list  = list;
    if (drmIoctl(fd, DRM_IOCTL_FREE_BUFS, &request))
	return -errno;
    return 0;
}


/**
 * Close the device.
 *
 * \param fd file descriptor.
 *
 * \internal
 * This function closes the file descriptor.
 */
int drmClose(int fd)
{
    unsigned long key    = drmGetKeyFromFd(fd);
    drmHashEntry  *entry = drmGetEntry(fd);

    drmHashDestroy(entry->tagTable);
    entry->fd       = 0;
    entry->f        = NULL;
    entry->tagTable = NULL;

    drmHashDelete(drmHashTable, key);
    drmFree(entry);

    return close(fd);
}


/**
 * Map a region of memory.
 *
 * \param fd file descriptor.
 * \param handle handle returned by drmAddMap().
 * \param size size in bytes. Must match the size used by drmAddMap().
 * \param address will contain the user-space virtual address where the mapping
 * begins.
 *
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper for mmap().
 */
int drmMap(int fd, drm_handle_t handle, drmSize size, drmAddressPtr address)
{
    static unsigned long pagesize_mask = 0;

    if (fd < 0)
	return -EINVAL;

    if (!pagesize_mask)
	pagesize_mask = getpagesize() - 1;

    size = (size + pagesize_mask) & ~pagesize_mask;

    *address = mmap(0, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, handle);
    if (*address == MAP_FAILED)
	return -errno;
    return 0;
}


/**
 * Unmap mappings obtained with drmMap().
 *
 * \param address address as given by drmMap().
 * \param size size in bytes. Must match the size used by drmMap().
 * 
 * \return zero on success, or a negative value on failure.
 *
 * \internal
 * This function is a wrapper for munmap().
 */
int drmUnmap(drmAddress address, drmSize size)
{
    return munmap(address, size);
}

drmBufInfoPtr drmGetBufInfo(int fd)
{
    drm_buf_info_t info;
    drmBufInfoPtr  retval;
    int            i;

    info.count = 0;
    info.list  = NULL;

    if (drmIoctl(fd, DRM_IOCTL_INFO_BUFS, &info))
	return NULL;

    if (info.count) {
	if (!(info.list = drmMalloc(info.count * sizeof(*info.list))))
	    return NULL;

	if (drmIoctl(fd, DRM_IOCTL_INFO_BUFS, &info)) {
	    drmFree(info.list);
	    return NULL;
	}

	retval = drmMalloc(sizeof(*retval));
	retval->count = info.count;
	retval->list  = drmMalloc(info.count * sizeof(*retval->list));
	for (i = 0; i < info.count; i++) {
	    retval->list[i].count     = info.list[i].count;
	    retval->list[i].size      = info.list[i].size;
	    retval->list[i].low_mark  = info.list[i].low_mark;
	    retval->list[i].high_mark = info.list[i].high_mark;
	}
	drmFree(info.list);
	return retval;
    }
    return NULL;
}

/**
 * Map all DMA buffers into client-virtual space.
 *
 * \param fd file descriptor.
 *
 * \return a pointer to a ::drmBufMap structure.
 *
 * \note The client may not use these buffers until obtaining buffer indices
 * with drmDMA().
 * 
 * \internal
 * This function calls the DRM_IOCTL_MAP_BUFS ioctl and copies the returned
 * information about the buffers in a drm_buf_map structure into the
 * client-visible data structures.
 */ 
drmBufMapPtr drmMapBufs(int fd)
{
    drm_buf_map_t bufs;
    drmBufMapPtr  retval;
    int           i;

    bufs.count = 0;
    bufs.list  = NULL;
    bufs.virtual = NULL;
    if (drmIoctl(fd, DRM_IOCTL_MAP_BUFS, &bufs))
	return NULL;

    if (!bufs.count)
	return NULL;

	if (!(bufs.list = drmMalloc(bufs.count * sizeof(*bufs.list))))
	    return NULL;

	if (drmIoctl(fd, DRM_IOCTL_MAP_BUFS, &bufs)) {
	    drmFree(bufs.list);
	    return NULL;
	}

	retval = drmMalloc(sizeof(*retval));
	retval->count = bufs.count;
	retval->list  = drmMalloc(bufs.count * sizeof(*retval->list));
	for (i = 0; i < bufs.count; i++) {
	    retval->list[i].idx     = bufs.list[i].idx;
	    retval->list[i].total   = bufs.list[i].total;
	    retval->list[i].used    = 0;
	    retval->list[i].address = bufs.list[i].address;
	}

	drmFree(bufs.list);
	
	return retval;
}


/**
 * Unmap buffers allocated with drmMapBufs().
 *
 * \return zero on success, or negative value on failure.
 *
 * \internal
 * Calls munmap() for every buffer stored in \p bufs and frees the
 * memory allocated by drmMapBufs().
 */
int drmUnmapBufs(drmBufMapPtr bufs)
{
    int i;

    for (i = 0; i < bufs->count; i++) {
	munmap(bufs->list[i].address, bufs->list[i].total);
    }

    drmFree(bufs->list);
    drmFree(bufs);
	
    return 0;
}


#define DRM_DMA_RETRY		16

/**
 * Reserve DMA buffers.
 *
 * \param fd file descriptor.
 * \param request 
 * 
 * \return zero on success, or a negative value on failure.
 *
 * \internal
 * Assemble the arguments into a drm_dma structure and keeps issuing the
 * DRM_IOCTL_DMA ioctl until success or until maximum number of retries.
 */
int drmDMA(int fd, drmDMAReqPtr request)
{
    drm_dma_t dma;
    int ret, i = 0;

    dma.context         = request->context;
    dma.send_count      = request->send_count;
    dma.send_indices    = request->send_list;
    dma.send_sizes      = request->send_sizes;
    dma.flags           = request->flags;
    dma.request_count   = request->request_count;
    dma.request_size    = request->request_size;
    dma.request_indices = request->request_list;
    dma.request_sizes   = request->request_sizes;
    dma.granted_count   = 0;

    do {
	ret = ioctl( fd, DRM_IOCTL_DMA, &dma );
    } while ( ret && errno == EAGAIN && i++ < DRM_DMA_RETRY );

    if ( ret == 0 ) {
	request->granted_count = dma.granted_count;
	return 0;
    } else {
	return -errno;
    }
}


/**
 * Obtain heavyweight hardware lock.
 *
 * \param fd file descriptor.
 * \param context context.
 * \param flags flags that determine the sate of the hardware when the function
 * returns.
 * 
 * \return always zero.
 * 
 * \internal
 * This function translates the arguments into a drm_lock structure and issue
 * the DRM_IOCTL_LOCK ioctl until the lock is successfully acquired.
 */
int drmGetLock(int fd, drm_context_t context, drmLockFlags flags)
{
    drm_lock_t lock;

    lock.context = context;
    lock.flags   = 0;
    if (flags & DRM_LOCK_READY)      lock.flags |= _DRM_LOCK_READY;
    if (flags & DRM_LOCK_QUIESCENT)  lock.flags |= _DRM_LOCK_QUIESCENT;
    if (flags & DRM_LOCK_FLUSH)      lock.flags |= _DRM_LOCK_FLUSH;
    if (flags & DRM_LOCK_FLUSH_ALL)  lock.flags |= _DRM_LOCK_FLUSH_ALL;
    if (flags & DRM_HALT_ALL_QUEUES) lock.flags |= _DRM_HALT_ALL_QUEUES;
    if (flags & DRM_HALT_CUR_QUEUES) lock.flags |= _DRM_HALT_CUR_QUEUES;

    while (drmIoctl(fd, DRM_IOCTL_LOCK, &lock))
	;
    return 0;
}

/**
 * Release the hardware lock.
 *
 * \param fd file descriptor.
 * \param context context.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_UNLOCK ioctl, passing the
 * argument in a drm_lock structure.
 */
int drmUnlock(int fd, drm_context_t context)
{
    drm_lock_t lock;

    lock.context = context;
    lock.flags   = 0;
    return drmIoctl(fd, DRM_IOCTL_UNLOCK, &lock);
}

drm_context_t *drmGetReservedContextList(int fd, int *count)
{
    drm_ctx_res_t res;
    drm_ctx_t     *list;
    drm_context_t * retval;
    int           i;

    res.count    = 0;
    res.contexts = NULL;
    if (drmIoctl(fd, DRM_IOCTL_RES_CTX, &res))
	return NULL;

    if (!res.count)
	return NULL;

    if (!(list   = drmMalloc(res.count * sizeof(*list))))
	return NULL;
    if (!(retval = drmMalloc(res.count * sizeof(*retval)))) {
	drmFree(list);
	return NULL;
    }

    res.contexts = list;
    if (drmIoctl(fd, DRM_IOCTL_RES_CTX, &res))
	return NULL;

    for (i = 0; i < res.count; i++)
	retval[i] = list[i].handle;
    drmFree(list);

    *count = res.count;
    return retval;
}

void drmFreeReservedContextList(drm_context_t *pt)
{
    drmFree(pt);
}

/**
 * Create context.
 *
 * Used by the X server during GLXContext initialization. This causes
 * per-context kernel-level resources to be allocated.
 *
 * \param fd file descriptor.
 * \param handle is set on success. To be used by the client when requesting DMA
 * dispatch with drmDMA().
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \note May only be called by root.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_ADD_CTX ioctl, passing the
 * argument in a drm_ctx structure.
 */
int drmCreateContext(int fd, drm_context_t *handle)
{
    drm_ctx_t ctx;

    ctx.flags = 0;	/* Modified with functions below */
    if (drmIoctl(fd, DRM_IOCTL_ADD_CTX, &ctx))
	return -errno;
    *handle = ctx.handle;
    return 0;
}

int drmSwitchToContext(int fd, drm_context_t context)
{
    drm_ctx_t ctx;

    ctx.handle = context;
    if (drmIoctl(fd, DRM_IOCTL_SWITCH_CTX, &ctx))
	return -errno;
    return 0;
}

int drmSetContextFlags(int fd, drm_context_t context, drm_context_tFlags flags)
{
    drm_ctx_t ctx;

    /*
     * Context preserving means that no context switches are done between DMA
     * buffers from one context and the next.  This is suitable for use in the
     * X server (which promises to maintain hardware context), or in the
     * client-side library when buffers are swapped on behalf of two threads.
     */
    ctx.handle = context;
    ctx.flags  = 0;
    if (flags & DRM_CONTEXT_PRESERVED)
	ctx.flags |= _DRM_CONTEXT_PRESERVED;
    if (flags & DRM_CONTEXT_2DONLY)
	ctx.flags |= _DRM_CONTEXT_2DONLY;
    if (drmIoctl(fd, DRM_IOCTL_MOD_CTX, &ctx))
	return -errno;
    return 0;
}

int drmGetContextFlags(int fd, drm_context_t context,
                       drm_context_tFlagsPtr flags)
{
    drm_ctx_t ctx;

    ctx.handle = context;
    if (drmIoctl(fd, DRM_IOCTL_GET_CTX, &ctx))
	return -errno;
    *flags = 0;
    if (ctx.flags & _DRM_CONTEXT_PRESERVED)
	*flags |= DRM_CONTEXT_PRESERVED;
    if (ctx.flags & _DRM_CONTEXT_2DONLY)
	*flags |= DRM_CONTEXT_2DONLY;
    return 0;
}

/**
 * Destroy context.
 *
 * Free any kernel-level resources allocated with drmCreateContext() associated
 * with the context.
 * 
 * \param fd file descriptor.
 * \param handle handle given by drmCreateContext().
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \note May only be called by root.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_RM_CTX ioctl, passing the
 * argument in a drm_ctx structure.
 */
int drmDestroyContext(int fd, drm_context_t handle)
{
    drm_ctx_t ctx;
    ctx.handle = handle;
    if (drmIoctl(fd, DRM_IOCTL_RM_CTX, &ctx))
	return -errno;
    return 0;
}

int drmCreateDrawable(int fd, drm_drawable_t *handle)
{
    drm_draw_t draw;
    if (drmIoctl(fd, DRM_IOCTL_ADD_DRAW, &draw))
	return -errno;
    *handle = draw.handle;
    return 0;
}

int drmDestroyDrawable(int fd, drm_drawable_t handle)
{
    drm_draw_t draw;
    draw.handle = handle;
    if (drmIoctl(fd, DRM_IOCTL_RM_DRAW, &draw))
	return -errno;
    return 0;
}

int drmUpdateDrawableInfo(int fd, drm_drawable_t handle,
			   drm_drawable_info_type_t type, unsigned int num,
			   void *data)
{
    drm_update_draw_t update;

    update.handle = handle;
    update.type = type;
    update.num = num;
    update.data = (unsigned long long)(unsigned long)data;

    if (drmIoctl(fd, DRM_IOCTL_UPDATE_DRAW, &update))
	return -errno;

    return 0;
}

/**
 * Acquire the AGP device.
 *
 * Must be called before any of the other AGP related calls.
 *
 * \param fd file descriptor.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_ACQUIRE ioctl.
 */
int drmAgpAcquire(int fd)
{
    if (drmIoctl(fd, DRM_IOCTL_AGP_ACQUIRE, NULL))
	return -errno;
    return 0;
}


/**
 * Release the AGP device.
 *
 * \param fd file descriptor.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_RELEASE ioctl.
 */
int drmAgpRelease(int fd)
{
    if (drmIoctl(fd, DRM_IOCTL_AGP_RELEASE, NULL))
	return -errno;
    return 0;
}


/**
 * Set the AGP mode.
 *
 * \param fd file descriptor.
 * \param mode AGP mode.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_ENABLE ioctl, passing the
 * argument in a drm_agp_mode structure.
 */
int drmAgpEnable(int fd, unsigned long mode)
{
    drm_agp_mode_t m;

    m.mode = mode;
    if (drmIoctl(fd, DRM_IOCTL_AGP_ENABLE, &m))
	return -errno;
    return 0;
}


/**
 * Allocate a chunk of AGP memory.
 *
 * \param fd file descriptor.
 * \param size requested memory size in bytes. Will be rounded to page boundary.
 * \param type type of memory to allocate.
 * \param address if not zero, will be set to the physical address of the
 * allocated memory.
 * \param handle on success will be set to a handle of the allocated memory.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_ALLOC ioctl, passing the
 * arguments in a drm_agp_buffer structure.
 */
int drmAgpAlloc(int fd, unsigned long size, unsigned long type,
		unsigned long *address, drm_handle_t *handle)
{
    drm_agp_buffer_t b;

    *handle = DRM_AGP_NO_HANDLE;
    b.size   = size;
    b.handle = 0;
    b.type   = type;
    if (drmIoctl(fd, DRM_IOCTL_AGP_ALLOC, &b))
	return -errno;
    if (address != 0UL)
	*address = b.physical;
    *handle = b.handle;
    return 0;
}


/**
 * Free a chunk of AGP memory.
 *
 * \param fd file descriptor.
 * \param handle handle to the allocated memory, as given by drmAgpAllocate().
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_FREE ioctl, passing the
 * argument in a drm_agp_buffer structure.
 */
int drmAgpFree(int fd, drm_handle_t handle)
{
    drm_agp_buffer_t b;

    b.size   = 0;
    b.handle = handle;
    if (drmIoctl(fd, DRM_IOCTL_AGP_FREE, &b))
	return -errno;
    return 0;
}


/**
 * Bind a chunk of AGP memory.
 *
 * \param fd file descriptor.
 * \param handle handle to the allocated memory, as given by drmAgpAllocate().
 * \param offset offset in bytes. It will round to page boundary.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_BIND ioctl, passing the
 * argument in a drm_agp_binding structure.
 */
int drmAgpBind(int fd, drm_handle_t handle, unsigned long offset)
{
    drm_agp_binding_t b;

    b.handle = handle;
    b.offset = offset;
    if (drmIoctl(fd, DRM_IOCTL_AGP_BIND, &b))
	return -errno;
    return 0;
}


/**
 * Unbind a chunk of AGP memory.
 *
 * \param fd file descriptor.
 * \param handle handle to the allocated memory, as given by drmAgpAllocate().
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_UNBIND ioctl, passing
 * the argument in a drm_agp_binding structure.
 */
int drmAgpUnbind(int fd, drm_handle_t handle)
{
    drm_agp_binding_t b;

    b.handle = handle;
    b.offset = 0;
    if (drmIoctl(fd, DRM_IOCTL_AGP_UNBIND, &b))
	return -errno;
    return 0;
}


/**
 * Get AGP driver major version number.
 *
 * \param fd file descriptor.
 * 
 * \return major version number on success, or a negative value on failure..
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_INFO ioctl, getting the
 * necessary information in a drm_agp_info structure.
 */
int drmAgpVersionMajor(int fd)
{
    drm_agp_info_t i;

    if (drmIoctl(fd, DRM_IOCTL_AGP_INFO, &i))
	return -errno;
    return i.agp_version_major;
}


/**
 * Get AGP driver minor version number.
 *
 * \param fd file descriptor.
 * 
 * \return minor version number on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_INFO ioctl, getting the
 * necessary information in a drm_agp_info structure.
 */
int drmAgpVersionMinor(int fd)
{
    drm_agp_info_t i;

    if (drmIoctl(fd, DRM_IOCTL_AGP_INFO, &i))
	return -errno;
    return i.agp_version_minor;
}


/**
 * Get AGP mode.
 *
 * \param fd file descriptor.
 * 
 * \return mode on success, or zero on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_INFO ioctl, getting the
 * necessary information in a drm_agp_info structure.
 */
unsigned long drmAgpGetMode(int fd)
{
    drm_agp_info_t i;

    if (drmIoctl(fd, DRM_IOCTL_AGP_INFO, &i))
	return 0;
    return i.mode;
}


/**
 * Get AGP aperture base.
 *
 * \param fd file descriptor.
 * 
 * \return aperture base on success, zero on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_INFO ioctl, getting the
 * necessary information in a drm_agp_info structure.
 */
unsigned long drmAgpBase(int fd)
{
    drm_agp_info_t i;

    if (drmIoctl(fd, DRM_IOCTL_AGP_INFO, &i))
	return 0;
    return i.aperture_base;
}


/**
 * Get AGP aperture size.
 *
 * \param fd file descriptor.
 * 
 * \return aperture size on success, zero on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_INFO ioctl, getting the
 * necessary information in a drm_agp_info structure.
 */
unsigned long drmAgpSize(int fd)
{
    drm_agp_info_t i;

    if (drmIoctl(fd, DRM_IOCTL_AGP_INFO, &i))
	return 0;
    return i.aperture_size;
}


/**
 * Get used AGP memory.
 *
 * \param fd file descriptor.
 * 
 * \return memory used on success, or zero on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_INFO ioctl, getting the
 * necessary information in a drm_agp_info structure.
 */
unsigned long drmAgpMemoryUsed(int fd)
{
    drm_agp_info_t i;

    if (drmIoctl(fd, DRM_IOCTL_AGP_INFO, &i))
	return 0;
    return i.memory_used;
}


/**
 * Get available AGP memory.
 *
 * \param fd file descriptor.
 * 
 * \return memory available on success, or zero on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_INFO ioctl, getting the
 * necessary information in a drm_agp_info structure.
 */
unsigned long drmAgpMemoryAvail(int fd)
{
    drm_agp_info_t i;

    if (drmIoctl(fd, DRM_IOCTL_AGP_INFO, &i))
	return 0;
    return i.memory_allowed;
}


/**
 * Get hardware vendor ID.
 *
 * \param fd file descriptor.
 * 
 * \return vendor ID on success, or zero on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_INFO ioctl, getting the
 * necessary information in a drm_agp_info structure.
 */
unsigned int drmAgpVendorId(int fd)
{
    drm_agp_info_t i;

    if (drmIoctl(fd, DRM_IOCTL_AGP_INFO, &i))
	return 0;
    return i.id_vendor;
}


/**
 * Get hardware device ID.
 *
 * \param fd file descriptor.
 * 
 * \return zero on success, or zero on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_AGP_INFO ioctl, getting the
 * necessary information in a drm_agp_info structure.
 */
unsigned int drmAgpDeviceId(int fd)
{
    drm_agp_info_t i;

    if (drmIoctl(fd, DRM_IOCTL_AGP_INFO, &i))
	return 0;
    return i.id_device;
}

int drmScatterGatherAlloc(int fd, unsigned long size, drm_handle_t *handle)
{
    drm_scatter_gather_t sg;

    *handle = 0;
    sg.size   = size;
    sg.handle = 0;
    if (drmIoctl(fd, DRM_IOCTL_SG_ALLOC, &sg))
	return -errno;
    *handle = sg.handle;
    return 0;
}

int drmScatterGatherFree(int fd, drm_handle_t handle)
{
    drm_scatter_gather_t sg;

    sg.size   = 0;
    sg.handle = handle;
    if (drmIoctl(fd, DRM_IOCTL_SG_FREE, &sg))
	return -errno;
    return 0;
}

/**
 * Wait for VBLANK.
 *
 * \param fd file descriptor.
 * \param vbl pointer to a drmVBlank structure.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_WAIT_VBLANK ioctl.
 */
int drmWaitVBlank(int fd, drmVBlankPtr vbl)
{
    struct timespec timeout, cur;
    int ret;

    ret = clock_gettime(CLOCK_MONOTONIC, &timeout);
    if (ret < 0) {
	fprintf(stderr, "clock_gettime failed: %s\n", strerror(ret));
	goto out;
    }
    timeout.tv_sec++;

    do {
       ret = ioctl(fd, DRM_IOCTL_WAIT_VBLANK, vbl);
       vbl->request.type &= ~DRM_VBLANK_RELATIVE;
       if (ret && errno == EINTR) {
	       clock_gettime(CLOCK_MONOTONIC, &cur);
	       /* Timeout after 1s */
	       if (cur.tv_sec > timeout.tv_sec + 1 ||
		   (cur.tv_sec == timeout.tv_sec && cur.tv_nsec >=
		    timeout.tv_nsec)) {
		       errno = EBUSY;
		       ret = -1;
		       break;
	       }
       }
    } while (ret && errno == EINTR);

out:
    return ret;
}

int drmError(int err, const char *label)
{
    switch (err) {
    case DRM_ERR_NO_DEVICE:
	fprintf(stderr, "%s: no device\n", label);
	break;
    case DRM_ERR_NO_ACCESS:
	fprintf(stderr, "%s: no access\n", label);
	break;
    case DRM_ERR_NOT_ROOT:
	fprintf(stderr, "%s: not root\n", label);
	break;
    case DRM_ERR_INVALID:
	fprintf(stderr, "%s: invalid args\n", label);
	break;
    default:
	if (err < 0)
	    err = -err;
	fprintf( stderr, "%s: error %d (%s)\n", label, err, strerror(err) );
	break;
    }

    return 1;
}

/**
 * Install IRQ handler.
 *
 * \param fd file descriptor.
 * \param irq IRQ number.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_CONTROL ioctl, passing the
 * argument in a drm_control structure.
 */
int drmCtlInstHandler(int fd, int irq)
{
    drm_control_t ctl;

    ctl.func  = DRM_INST_HANDLER;
    ctl.irq   = irq;
    if (drmIoctl(fd, DRM_IOCTL_CONTROL, &ctl))
	return -errno;
    return 0;
}


/**
 * Uninstall IRQ handler.
 *
 * \param fd file descriptor.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_CONTROL ioctl, passing the
 * argument in a drm_control structure.
 */
int drmCtlUninstHandler(int fd)
{
    drm_control_t ctl;

    ctl.func  = DRM_UNINST_HANDLER;
    ctl.irq   = 0;
    if (drmIoctl(fd, DRM_IOCTL_CONTROL, &ctl))
	return -errno;
    return 0;
}

int drmFinish(int fd, int context, drmLockFlags flags)
{
    drm_lock_t lock;

    lock.context = context;
    lock.flags   = 0;
    if (flags & DRM_LOCK_READY)      lock.flags |= _DRM_LOCK_READY;
    if (flags & DRM_LOCK_QUIESCENT)  lock.flags |= _DRM_LOCK_QUIESCENT;
    if (flags & DRM_LOCK_FLUSH)      lock.flags |= _DRM_LOCK_FLUSH;
    if (flags & DRM_LOCK_FLUSH_ALL)  lock.flags |= _DRM_LOCK_FLUSH_ALL;
    if (flags & DRM_HALT_ALL_QUEUES) lock.flags |= _DRM_HALT_ALL_QUEUES;
    if (flags & DRM_HALT_CUR_QUEUES) lock.flags |= _DRM_HALT_CUR_QUEUES;
    if (drmIoctl(fd, DRM_IOCTL_FINISH, &lock))
	return -errno;
    return 0;
}

/**
 * Get IRQ from bus ID.
 *
 * \param fd file descriptor.
 * \param busnum bus number.
 * \param devnum device number.
 * \param funcnum function number.
 * 
 * \return IRQ number on success, or a negative value on failure.
 * 
 * \internal
 * This function is a wrapper around the DRM_IOCTL_IRQ_BUSID ioctl, passing the
 * arguments in a drm_irq_busid structure.
 */
int drmGetInterruptFromBusID(int fd, int busnum, int devnum, int funcnum)
{
    drm_irq_busid_t p;

    p.busnum  = busnum;
    p.devnum  = devnum;
    p.funcnum = funcnum;
    if (drmIoctl(fd, DRM_IOCTL_IRQ_BUSID, &p))
	return -errno;
    return p.irq;
}

int drmAddContextTag(int fd, drm_context_t context, void *tag)
{
    drmHashEntry  *entry = drmGetEntry(fd);

    if (drmHashInsert(entry->tagTable, context, tag)) {
	drmHashDelete(entry->tagTable, context);
	drmHashInsert(entry->tagTable, context, tag);
    }
    return 0;
}

int drmDelContextTag(int fd, drm_context_t context)
{
    drmHashEntry  *entry = drmGetEntry(fd);

    return drmHashDelete(entry->tagTable, context);
}

void *drmGetContextTag(int fd, drm_context_t context)
{
    drmHashEntry  *entry = drmGetEntry(fd);
    void          *value;

    if (drmHashLookup(entry->tagTable, context, &value))
	return NULL;

    return value;
}

int drmAddContextPrivateMapping(int fd, drm_context_t ctx_id,
                                drm_handle_t handle)
{
    drm_ctx_priv_map_t map;

    map.ctx_id = ctx_id;
    map.handle = (void *)(uintptr_t)handle;

    if (drmIoctl(fd, DRM_IOCTL_SET_SAREA_CTX, &map))
	return -errno;
    return 0;
}

int drmGetContextPrivateMapping(int fd, drm_context_t ctx_id,
                                drm_handle_t *handle)
{
    drm_ctx_priv_map_t map;

    map.ctx_id = ctx_id;

    if (drmIoctl(fd, DRM_IOCTL_GET_SAREA_CTX, &map))
	return -errno;
    if (handle)
	*handle = (drm_handle_t)(uintptr_t)map.handle;

    return 0;
}

int drmGetMap(int fd, int idx, drm_handle_t *offset, drmSize *size,
	      drmMapType *type, drmMapFlags *flags, drm_handle_t *handle,
	      int *mtrr)
{
    drm_map_t map;

    map.offset = idx;
    if (drmIoctl(fd, DRM_IOCTL_GET_MAP, &map))
	return -errno;
    *offset = map.offset;
    *size   = map.size;
    *type   = map.type;
    *flags  = map.flags;
    *handle = (unsigned long)map.handle;
    *mtrr   = map.mtrr;
    return 0;
}

int drmGetClient(int fd, int idx, int *auth, int *pid, int *uid,
		 unsigned long *magic, unsigned long *iocs)
{
    drm_client_t client;

    client.idx = idx;
    if (drmIoctl(fd, DRM_IOCTL_GET_CLIENT, &client))
	return -errno;
    *auth      = client.auth;
    *pid       = client.pid;
    *uid       = client.uid;
    *magic     = client.magic;
    *iocs      = client.iocs;
    return 0;
}

int drmGetStats(int fd, drmStatsT *stats)
{
    drm_stats_t s;
    int         i;

    if (drmIoctl(fd, DRM_IOCTL_GET_STATS, &s))
	return -errno;

    stats->count = 0;
    memset(stats, 0, sizeof(*stats));
    if (s.count > sizeof(stats->data)/sizeof(stats->data[0]))
	return -1;

#define SET_VALUE                              \
    stats->data[i].long_format = "%-20.20s";   \
    stats->data[i].rate_format = "%8.8s";      \
    stats->data[i].isvalue     = 1;            \
    stats->data[i].verbose     = 0

#define SET_COUNT                              \
    stats->data[i].long_format = "%-20.20s";   \
    stats->data[i].rate_format = "%5.5s";      \
    stats->data[i].isvalue     = 0;            \
    stats->data[i].mult_names  = "kgm";        \
    stats->data[i].mult        = 1000;         \
    stats->data[i].verbose     = 0

#define SET_BYTE                               \
    stats->data[i].long_format = "%-20.20s";   \
    stats->data[i].rate_format = "%5.5s";      \
    stats->data[i].isvalue     = 0;            \
    stats->data[i].mult_names  = "KGM";        \
    stats->data[i].mult        = 1024;         \
    stats->data[i].verbose     = 0


    stats->count = s.count;
    for (i = 0; i < s.count; i++) {
	stats->data[i].value = s.data[i].value;
	switch (s.data[i].type) {
	case _DRM_STAT_LOCK:
	    stats->data[i].long_name = "Lock";
	    stats->data[i].rate_name = "Lock";
	    SET_VALUE;
	    break;
	case _DRM_STAT_OPENS:
	    stats->data[i].long_name = "Opens";
	    stats->data[i].rate_name = "O";
	    SET_COUNT;
	    stats->data[i].verbose   = 1;
	    break;
	case _DRM_STAT_CLOSES:
	    stats->data[i].long_name = "Closes";
	    stats->data[i].rate_name = "Lock";
	    SET_COUNT;
	    stats->data[i].verbose   = 1;
	    break;
	case _DRM_STAT_IOCTLS:
	    stats->data[i].long_name = "Ioctls";
	    stats->data[i].rate_name = "Ioc/s";
	    SET_COUNT;
	    break;
	case _DRM_STAT_LOCKS:
	    stats->data[i].long_name = "Locks";
	    stats->data[i].rate_name = "Lck/s";
	    SET_COUNT;
	    break;
	case _DRM_STAT_UNLOCKS:
	    stats->data[i].long_name = "Unlocks";
	    stats->data[i].rate_name = "Unl/s";
	    SET_COUNT;
	    break;
	case _DRM_STAT_IRQ:
	    stats->data[i].long_name = "IRQs";
	    stats->data[i].rate_name = "IRQ/s";
	    SET_COUNT;
	    break;
	case _DRM_STAT_PRIMARY:
	    stats->data[i].long_name = "Primary Bytes";
	    stats->data[i].rate_name = "PB/s";
	    SET_BYTE;
	    break;
	case _DRM_STAT_SECONDARY:
	    stats->data[i].long_name = "Secondary Bytes";
	    stats->data[i].rate_name = "SB/s";
	    SET_BYTE;
	    break;
	case _DRM_STAT_DMA:
	    stats->data[i].long_name = "DMA";
	    stats->data[i].rate_name = "DMA/s";
	    SET_COUNT;
	    break;
	case _DRM_STAT_SPECIAL:
	    stats->data[i].long_name = "Special DMA";
	    stats->data[i].rate_name = "dma/s";
	    SET_COUNT;
	    break;
	case _DRM_STAT_MISSED:
	    stats->data[i].long_name = "Miss";
	    stats->data[i].rate_name = "Ms/s";
	    SET_COUNT;
	    break;
	case _DRM_STAT_VALUE:
	    stats->data[i].long_name = "Value";
	    stats->data[i].rate_name = "Value";
	    SET_VALUE;
	    break;
	case _DRM_STAT_BYTE:
	    stats->data[i].long_name = "Bytes";
	    stats->data[i].rate_name = "B/s";
	    SET_BYTE;
	    break;
	case _DRM_STAT_COUNT:
	default:
	    stats->data[i].long_name = "Count";
	    stats->data[i].rate_name = "Cnt/s";
	    SET_COUNT;
	    break;
	}
    }
    return 0;
}

/**
 * Issue a set-version ioctl.
 *
 * \param fd file descriptor.
 * \param drmCommandIndex command index 
 * \param data source pointer of the data to be read and written.
 * \param size size of the data to be read and written.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * It issues a read-write ioctl given by 
 * \code DRM_COMMAND_BASE + drmCommandIndex \endcode.
 */
int drmSetInterfaceVersion(int fd, drmSetVersion *version)
{
    int retcode = 0;
    drm_set_version_t sv;

    sv.drm_di_major = version->drm_di_major;
    sv.drm_di_minor = version->drm_di_minor;
    sv.drm_dd_major = version->drm_dd_major;
    sv.drm_dd_minor = version->drm_dd_minor;

    if (drmIoctl(fd, DRM_IOCTL_SET_VERSION, &sv)) {
	retcode = -errno;
    }

    version->drm_di_major = sv.drm_di_major;
    version->drm_di_minor = sv.drm_di_minor;
    version->drm_dd_major = sv.drm_dd_major;
    version->drm_dd_minor = sv.drm_dd_minor;

    return retcode;
}

/**
 * Send a device-specific command.
 *
 * \param fd file descriptor.
 * \param drmCommandIndex command index 
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * It issues a ioctl given by 
 * \code DRM_COMMAND_BASE + drmCommandIndex \endcode.
 */
int drmCommandNone(int fd, unsigned long drmCommandIndex)
{
    void *data = NULL; /* dummy */
    unsigned long request;

    request = DRM_IO( DRM_COMMAND_BASE + drmCommandIndex);

    if (drmIoctl(fd, request, data)) {
	return -errno;
    }
    return 0;
}


/**
 * Send a device-specific read command.
 *
 * \param fd file descriptor.
 * \param drmCommandIndex command index 
 * \param data destination pointer of the data to be read.
 * \param size size of the data to be read.
 * 
 * \return zero on success, or a negative value on failure.
 *
 * \internal
 * It issues a read ioctl given by 
 * \code DRM_COMMAND_BASE + drmCommandIndex \endcode.
 */
int drmCommandRead(int fd, unsigned long drmCommandIndex, void *data,
                   unsigned long size)
{
    unsigned long request;

    request = DRM_IOC( DRM_IOC_READ, DRM_IOCTL_BASE, 
	DRM_COMMAND_BASE + drmCommandIndex, size);

    if (drmIoctl(fd, request, data)) {
	return -errno;
    }
    return 0;
}


/**
 * Send a device-specific write command.
 *
 * \param fd file descriptor.
 * \param drmCommandIndex command index 
 * \param data source pointer of the data to be written.
 * \param size size of the data to be written.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * It issues a write ioctl given by 
 * \code DRM_COMMAND_BASE + drmCommandIndex \endcode.
 */
int drmCommandWrite(int fd, unsigned long drmCommandIndex, void *data,
                    unsigned long size)
{
    unsigned long request;

    request = DRM_IOC( DRM_IOC_WRITE, DRM_IOCTL_BASE, 
	DRM_COMMAND_BASE + drmCommandIndex, size);

    if (drmIoctl(fd, request, data)) {
	return -errno;
    }
    return 0;
}


/**
 * Send a device-specific read-write command.
 *
 * \param fd file descriptor.
 * \param drmCommandIndex command index 
 * \param data source pointer of the data to be read and written.
 * \param size size of the data to be read and written.
 * 
 * \return zero on success, or a negative value on failure.
 * 
 * \internal
 * It issues a read-write ioctl given by 
 * \code DRM_COMMAND_BASE + drmCommandIndex \endcode.
 */
int drmCommandWriteRead(int fd, unsigned long drmCommandIndex, void *data,
                        unsigned long size)
{
    unsigned long request;

    request = DRM_IOC( DRM_IOC_READ|DRM_IOC_WRITE, DRM_IOCTL_BASE, 
	DRM_COMMAND_BASE + drmCommandIndex, size);

    if (drmIoctl(fd, request, data))
	return -errno;
    return 0;
}

#define DRM_MAX_FDS 16
static struct {
    char *BusID;
    int fd;
    int refcount;
} connection[DRM_MAX_FDS];

static int nr_fds = 0;

int drmOpenOnce(void *unused, 
		const char *BusID,
		int *newlyopened)
{
    int i;
    int fd;
   
    for (i = 0; i < nr_fds; i++)
	if (strcmp(BusID, connection[i].BusID) == 0) {
	    connection[i].refcount++;
	    *newlyopened = 0;
	    return connection[i].fd;
	}

    fd = drmOpen(unused, BusID);
    if (fd <= 0 || nr_fds == DRM_MAX_FDS)
	return fd;
   
    connection[nr_fds].BusID = strdup(BusID);
    connection[nr_fds].fd = fd;
    connection[nr_fds].refcount = 1;
    *newlyopened = 1;

    if (0)
	fprintf(stderr, "saved connection %d for %s %d\n", 
		nr_fds, connection[nr_fds].BusID, 
		strcmp(BusID, connection[nr_fds].BusID));

    nr_fds++;

    return fd;
}

void drmCloseOnce(int fd)
{
    int i;

    for (i = 0; i < nr_fds; i++) {
	if (fd == connection[i].fd) {
	    if (--connection[i].refcount == 0) {
		drmClose(connection[i].fd);
		free(connection[i].BusID);
	    
		if (i < --nr_fds) 
		    connection[i] = connection[nr_fds];

		return;
	    }
	}
    }
}

int drmSetMaster(int fd)
{
	return ioctl(fd, DRM_IOCTL_SET_MASTER, 0);
}

int drmDropMaster(int fd)
{
	return ioctl(fd, DRM_IOCTL_DROP_MASTER, 0);
}

char *drmGetDeviceNameFromFd(int fd)
{
	char name[128];
	struct stat sbuf;
	dev_t d;
	int i;

	/* The whole drmOpen thing is a fiasco and we need to find a way
	 * back to just using open(2).  For now, however, lets just make
	 * things worse with even more ad hoc directory walking code to
	 * discover the device file name. */

	fstat(fd, &sbuf);
	d = sbuf.st_rdev;

	for (i = 0; i < DRM_MAX_MINOR; i++) {
		snprintf(name, sizeof name, DRM_DEV_NAME, DRM_DIR_NAME, i);
		if (stat(name, &sbuf) == 0 && sbuf.st_rdev == d)
			break;
	}
	if (i == DRM_MAX_MINOR)
		return NULL;

	return strdup(name);
}

int drmPrimeHandleToFD(int fd, uint32_t handle, uint32_t flags, int *prime_fd)
{
	struct drm_prime_handle args;
	int ret;

	args.handle = handle;
	args.flags = flags;
	ret = drmIoctl(fd, DRM_IOCTL_PRIME_HANDLE_TO_FD, &args);
	if (ret)
		return ret;

	*prime_fd = args.fd;
	return 0;
}

int drmPrimeFDToHandle(int fd, int prime_fd, uint32_t *handle)
{
	struct drm_prime_handle args;
	int ret;

	args.fd = prime_fd;
	args.flags = 0;
	ret = drmIoctl(fd, DRM_IOCTL_PRIME_FD_TO_HANDLE, &args);
	if (ret)
		return ret;

	*handle = args.handle;
	return 0;
}