[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / gpu / drm / drm_context.c

/**
 * \file drm_context.c
 * IOCTLs for generic contexts
 *
 * \author Rickard E. (Rik) Faith <faith@valinux.com>
 * \author Gareth Hughes <gareth@valinux.com>
 */

/*
 * Created: Fri Nov 24 18:31:37 2000 by gareth@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.
 */

/*
 * ChangeLog:
 *  2001-11-16	Torsten Duwe <duwe@caldera.de>
 *		added context constructor/destructor hooks,
 *		needed by SiS driver's memory management.
 */

#include <drm/drmP.h>

/******************************************************************/
/** \name Context bitmap support */
/*@{*/

/**
 * Free a handle from the context bitmap.
 *
 * \param dev DRM device.
 * \param ctx_handle context handle.
 *
 * Clears the bit specified by \p ctx_handle in drm_device::ctx_bitmap and the entry
 * in drm_device::ctx_idr, while holding the drm_device::struct_mutex
 * lock.
 */
void drm_ctxbitmap_free(struct drm_device * dev, int ctx_handle)
{
	mutex_lock(&dev->struct_mutex);
	idr_remove(&dev->ctx_idr, ctx_handle);
	mutex_unlock(&dev->struct_mutex);
}

/**
 * Context bitmap allocation.
 *
 * \param dev DRM device.
 * \return (non-negative) context handle on success or a negative number on failure.
 *
 * Allocate a new idr from drm_device::ctx_idr while holding the
 * drm_device::struct_mutex lock.
 */
static int drm_ctxbitmap_next(struct drm_device * dev)
{
	int new_id;
	int ret;

again:
	if (idr_pre_get(&dev->ctx_idr, GFP_KERNEL) == 0) {
		DRM_ERROR("Out of memory expanding drawable idr\n");
		return -ENOMEM;
	}
	mutex_lock(&dev->struct_mutex);
	ret = idr_get_new_above(&dev->ctx_idr, NULL,
				DRM_RESERVED_CONTEXTS, &new_id);
	mutex_unlock(&dev->struct_mutex);
	if (ret == -EAGAIN)
		goto again;
	else if (ret)
		return ret;

	return new_id;
}

/**
 * Context bitmap initialization.
 *
 * \param dev DRM device.
 *
 * Initialise the drm_device::ctx_idr
 */
int drm_ctxbitmap_init(struct drm_device * dev)
{
	idr_init(&dev->ctx_idr);
	return 0;
}

/**
 * Context bitmap cleanup.
 *
 * \param dev DRM device.
 *
 * Free all idr members using drm_ctx_sarea_free helper function
 * while holding the drm_device::struct_mutex lock.
 */
void drm_ctxbitmap_cleanup(struct drm_device * dev)
{
	mutex_lock(&dev->struct_mutex);
	idr_remove_all(&dev->ctx_idr);
	mutex_unlock(&dev->struct_mutex);
}

/*@}*/

/******************************************************************/
/** \name Per Context SAREA Support */
/*@{*/

/**
 * Get per-context SAREA.
 *
 * \param inode device inode.
 * \param file_priv DRM file private.
 * \param cmd command.
 * \param arg user argument pointing to a drm_ctx_priv_map structure.
 * \return zero on success or a negative number on failure.
 *
 * Gets the map from drm_device::ctx_idr with the handle specified and
 * returns its handle.
 */
int drm_getsareactx(struct drm_device *dev, void *data,
		    struct drm_file *file_priv)
{
	struct drm_ctx_priv_map *request = data;
	struct drm_local_map *map;
	struct drm_map_list *_entry;

	mutex_lock(&dev->struct_mutex);

	map = idr_find(&dev->ctx_idr, request->ctx_id);
	if (!map) {
		mutex_unlock(&dev->struct_mutex);
		return -EINVAL;
	}

	request->handle = NULL;
	list_for_each_entry(_entry, &dev->maplist, head) {
		if (_entry->map == map) {
			request->handle =
			    (void *)(unsigned long)_entry->user_token;
			break;
		}
	}

	mutex_unlock(&dev->struct_mutex);

	if (request->handle == NULL)
		return -EINVAL;

	return 0;
}

/**
 * Set per-context SAREA.
 *
 * \param inode device inode.
 * \param file_priv DRM file private.
 * \param cmd command.
 * \param arg user argument pointing to a drm_ctx_priv_map structure.
 * \return zero on success or a negative number on failure.
 *
 * Searches the mapping specified in \p arg and update the entry in
 * drm_device::ctx_idr with it.
 */
int drm_setsareactx(struct drm_device *dev, void *data,
		    struct drm_file *file_priv)
{
	struct drm_ctx_priv_map *request = data;
	struct drm_local_map *map = NULL;
	struct drm_map_list *r_list = NULL;

	mutex_lock(&dev->struct_mutex);
	list_for_each_entry(r_list, &dev->maplist, head) {
		if (r_list->map
		    && r_list->user_token == (unsigned long) request->handle)
			goto found;
	}
      bad:
	mutex_unlock(&dev->struct_mutex);
	return -EINVAL;

      found:
	map = r_list->map;
	if (!map)
		goto bad;

	if (IS_ERR(idr_replace(&dev->ctx_idr, map, request->ctx_id)))
		goto bad;

	mutex_unlock(&dev->struct_mutex);

	return 0;
}

/*@}*/

/******************************************************************/
/** \name The actual DRM context handling routines */
/*@{*/

/**
 * Switch context.
 *
 * \param dev DRM device.
 * \param old old context handle.
 * \param new new context handle.
 * \return zero on success or a negative number on failure.
 *
 * Attempt to set drm_device::context_flag.
 */
static int drm_context_switch(struct drm_device * dev, int old, int new)
{
	if (test_and_set_bit(0, &dev->context_flag)) {
		DRM_ERROR("Reentering -- FIXME\n");
		return -EBUSY;
	}

	DRM_DEBUG("Context switch from %d to %d\n", old, new);

	if (new == dev->last_context) {
		clear_bit(0, &dev->context_flag);
		return 0;
	}

	return 0;
}

/**
 * Complete context switch.
 *
 * \param dev DRM device.
 * \param new new context handle.
 * \return zero on success or a negative number on failure.
 *
 * Updates drm_device::last_context and drm_device::last_switch. Verifies the
 * hardware lock is held, clears the drm_device::context_flag and wakes up
 * drm_device::context_wait.
 */
static int drm_context_switch_complete(struct drm_device *dev,
				       struct drm_file *file_priv, int new)
{
	dev->last_context = new;	/* PRE/POST: This is the _only_ writer. */
	dev->last_switch = jiffies;

	if (!_DRM_LOCK_IS_HELD(file_priv->master->lock.hw_lock->lock)) {
		DRM_ERROR("Lock isn't held after context switch\n");
	}

	/* If a context switch is ever initiated
	   when the kernel holds the lock, release
	   that lock here. */
	clear_bit(0, &dev->context_flag);
	wake_up(&dev->context_wait);

	return 0;
}

/**
 * Reserve contexts.
 *
 * \param inode device inode.
 * \param file_priv DRM file private.
 * \param cmd command.
 * \param arg user argument pointing to a drm_ctx_res structure.
 * \return zero on success or a negative number on failure.
 */
int drm_resctx(struct drm_device *dev, void *data,
	       struct drm_file *file_priv)
{
	struct drm_ctx_res *res = data;
	struct drm_ctx ctx;
	int i;

	if (res->count >= DRM_RESERVED_CONTEXTS) {
		memset(&ctx, 0, sizeof(ctx));
		for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
			ctx.handle = i;
			if (copy_to_user(&res->contexts[i], &ctx, sizeof(ctx)))
				return -EFAULT;
		}
	}
	res->count = DRM_RESERVED_CONTEXTS;

	return 0;
}

/**
 * Add context.
 *
 * \param inode device inode.
 * \param file_priv DRM file private.
 * \param cmd command.
 * \param arg user argument pointing to a drm_ctx structure.
 * \return zero on success or a negative number on failure.
 *
 * Get a new handle for the context and copy to userspace.
 */
int drm_addctx(struct drm_device *dev, void *data,
	       struct drm_file *file_priv)
{
	struct drm_ctx_list *ctx_entry;
	struct drm_ctx *ctx = data;

	ctx->handle = drm_ctxbitmap_next(dev);
	if (ctx->handle == DRM_KERNEL_CONTEXT) {
		/* Skip kernel's context and get a new one. */
		ctx->handle = drm_ctxbitmap_next(dev);
	}
	DRM_DEBUG("%d\n", ctx->handle);
	if (ctx->handle == -1) {
		DRM_DEBUG("Not enough free contexts.\n");
		/* Should this return -EBUSY instead? */
		return -ENOMEM;
	}

	ctx_entry = kmalloc(sizeof(*ctx_entry), GFP_KERNEL);
	if (!ctx_entry) {
		DRM_DEBUG("out of memory\n");
		return -ENOMEM;
	}

	INIT_LIST_HEAD(&ctx_entry->head);
	ctx_entry->handle = ctx->handle;
	ctx_entry->tag = file_priv;

	mutex_lock(&dev->ctxlist_mutex);
	list_add(&ctx_entry->head, &dev->ctxlist);
	++dev->ctx_count;
	mutex_unlock(&dev->ctxlist_mutex);

	return 0;
}

int drm_modctx(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
	/* This does nothing */
	return 0;
}

/**
 * Get context.
 *
 * \param inode device inode.
 * \param file_priv DRM file private.
 * \param cmd command.
 * \param arg user argument pointing to a drm_ctx structure.
 * \return zero on success or a negative number on failure.
 */
int drm_getctx(struct drm_device *dev, void *data, struct drm_file *file_priv)
{
	struct drm_ctx *ctx = data;

	/* This is 0, because we don't handle any context flags */
	ctx->flags = 0;

	return 0;
}

/**
 * Switch context.
 *
 * \param inode device inode.
 * \param file_priv DRM file private.
 * \param cmd command.
 * \param arg user argument pointing to a drm_ctx structure.
 * \return zero on success or a negative number on failure.
 *
 * Calls context_switch().
 */
int drm_switchctx(struct drm_device *dev, void *data,
		  struct drm_file *file_priv)
{
	struct drm_ctx *ctx = data;

	DRM_DEBUG("%d\n", ctx->handle);
	return drm_context_switch(dev, dev->last_context, ctx->handle);
}

/**
 * New context.
 *
 * \param inode device inode.
 * \param file_priv DRM file private.
 * \param cmd command.
 * \param arg user argument pointing to a drm_ctx structure.
 * \return zero on success or a negative number on failure.
 *
 * Calls context_switch_complete().
 */
int drm_newctx(struct drm_device *dev, void *data,
	       struct drm_file *file_priv)
{
	struct drm_ctx *ctx = data;

	DRM_DEBUG("%d\n", ctx->handle);
	drm_context_switch_complete(dev, file_priv, ctx->handle);

	return 0;
}

/**
 * Remove context.
 *
 * \param inode device inode.
 * \param file_priv DRM file private.
 * \param cmd command.
 * \param arg user argument pointing to a drm_ctx structure.
 * \return zero on success or a negative number on failure.
 *
 * If not the special kernel context, calls ctxbitmap_free() to free the specified context.
 */
int drm_rmctx(struct drm_device *dev, void *data,
	      struct drm_file *file_priv)
{
	struct drm_ctx *ctx = data;

	DRM_DEBUG("%d\n", ctx->handle);
	if (ctx->handle != DRM_KERNEL_CONTEXT) {
		if (dev->driver->context_dtor)
			dev->driver->context_dtor(dev, ctx->handle);
		drm_ctxbitmap_free(dev, ctx->handle);
	}

	mutex_lock(&dev->ctxlist_mutex);
	if (!list_empty(&dev->ctxlist)) {
		struct drm_ctx_list *pos, *n;

		list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
			if (pos->handle == ctx->handle) {
				list_del(&pos->head);
				kfree(pos);
				--dev->ctx_count;
			}
		}
	}
	mutex_unlock(&dev->ctxlist_mutex);

	return 0;
}

/*@}*/
Commit	Line	Data
1da177e4	1	/**
b5e89ed5	2	* \file drm_context.c
1da177e4	3	* IOCTLs for generic contexts
b5e89ed5	4	*
1da177e4 LT	5	* \author Rickard E. (Rik) Faith <faith@valinux.com>
	6	* \author Gareth Hughes <gareth@valinux.com>
	7	*/
	8
	9	/*
	10	* Created: Fri Nov 24 18:31:37 2000 by gareth@valinux.com
	11	*
	12	* Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
	13	* Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
	14	* All Rights Reserved.
	15	*
	16	* Permission is hereby granted, free of charge, to any person obtaining a
	17	* copy of this software and associated documentation files (the "Software"),
	18	* to deal in the Software without restriction, including without limitation
	19	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	20	* and/or sell copies of the Software, and to permit persons to whom the
	21	* Software is furnished to do so, subject to the following conditions:
	22	*
	23	* The above copyright notice and this permission notice (including the next
	24	* paragraph) shall be included in all copies or substantial portions of the
	25	* Software.
	26	*
	27	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	28	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	29	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	30	* VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
	31	* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
	32	* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
	33	* OTHER DEALINGS IN THE SOFTWARE.
	34	*/
	35
	36	/*
	37	* ChangeLog:
	38	* 2001-11-16 Torsten Duwe <duwe@caldera.de>
	39	* added context constructor/destructor hooks,
	40	* needed by SiS driver's memory management.
	41	*/
	42
760285e7	43	#include <drm/drmP.h>
1da177e4 LT	44
	45	/******************************************************************/
	46	/** \name Context bitmap support */
	47	/@{/
	48
	49	/**
	50	* Free a handle from the context bitmap.
	51	*
	52	* \param dev DRM device.
	53	* \param ctx_handle context handle.
	54	*
	55	* Clears the bit specified by \p ctx_handle in drm_device::ctx_bitmap and the entry
62968144	56	* in drm_device::ctx_idr, while holding the drm_device::struct_mutex
1da177e4 LT	57	* lock.
1da177e4 LT	58	*/
84b1fd10	59	void drm_ctxbitmap_free(struct drm_device * dev, int ctx_handle)
1da177e4	60	{
62968144 DA	61	mutex_lock(&dev->struct_mutex);
	62	idr_remove(&dev->ctx_idr, ctx_handle);
	63	mutex_unlock(&dev->struct_mutex);
1da177e4 LT	64	}
1da177e4 LT	65
b5e89ed5	66	/**
1da177e4 LT	67	* Context bitmap allocation.
	68	*
	69	* \param dev DRM device.
	70	* \return (non-negative) context handle on success or a negative number on failure.
	71	*
62968144	72	* Allocate a new idr from drm_device::ctx_idr while holding the
30e2fb18	73	* drm_device::struct_mutex lock.
1da177e4	74	*/
84b1fd10	75	static int drm_ctxbitmap_next(struct drm_device * dev)
1da177e4	76	{
62968144 DA	77	int new_id;
62968144 DA	78	int ret;
1da177e4	79
62968144 DA	80	again:
	81	if (idr_pre_get(&dev->ctx_idr, GFP_KERNEL) == 0) {
	82	DRM_ERROR("Out of memory expanding drawable idr\n");
	83	return -ENOMEM;
	84	}
30e2fb18	85	mutex_lock(&dev->struct_mutex);
62968144 DA	86	ret = idr_get_new_above(&dev->ctx_idr, NULL,
62968144 DA	87	DRM_RESERVED_CONTEXTS, &new_id);
30e2fb18	88	mutex_unlock(&dev->struct_mutex);
f1ae126c VS	89	if (ret == -EAGAIN)
	90	goto again;
	91	else if (ret)
	92	return ret;
	93
62968144	94	return new_id;
1da177e4 LT	95	}
	96
	97	/**
	98	* Context bitmap initialization.
	99	*
	100	* \param dev DRM device.
	101	*
62968144	102	* Initialise the drm_device::ctx_idr
1da177e4	103	*/
84b1fd10	104	int drm_ctxbitmap_init(struct drm_device * dev)
1da177e4	105	{
62968144	106	idr_init(&dev->ctx_idr);
1da177e4 LT	107	return 0;
	108	}
	109
	110	/**
	111	* Context bitmap cleanup.
	112	*
	113	* \param dev DRM device.
	114	*
62968144 DA	115	* Free all idr members using drm_ctx_sarea_free helper function
62968144 DA	116	* while holding the drm_device::struct_mutex lock.
1da177e4	117	*/
84b1fd10	118	void drm_ctxbitmap_cleanup(struct drm_device * dev)
1da177e4	119	{
30e2fb18	120	mutex_lock(&dev->struct_mutex);
62968144	121	idr_remove_all(&dev->ctx_idr);
30e2fb18	122	mutex_unlock(&dev->struct_mutex);
1da177e4 LT	123	}
	124
	125	/@}/
	126
	127	/******************************************************************/
	128	/** \name Per Context SAREA Support */
	129	/@{/
	130
	131	/**
	132	* Get per-context SAREA.
b5e89ed5	133	*
1da177e4	134	* \param inode device inode.
6c340eac	135	* \param file_priv DRM file private.
1da177e4 LT	136	* \param cmd command.
	137	* \param arg user argument pointing to a drm_ctx_priv_map structure.
	138	* \return zero on success or a negative number on failure.
	139	*
62968144	140	* Gets the map from drm_device::ctx_idr with the handle specified and
1da177e4 LT	141	* returns its handle.
1da177e4 LT	142	*/
c153f45f EA	143	int drm_getsareactx(struct drm_device dev, void data,
c153f45f EA	144	struct drm_file *file_priv)
1da177e4	145	{
c153f45f	146	struct drm_ctx_priv_map *request = data;
f77d390c	147	struct drm_local_map *map;
55910517	148	struct drm_map_list *_entry;
1da177e4	149
30e2fb18	150	mutex_lock(&dev->struct_mutex);
62968144	151
c153f45f	152	map = idr_find(&dev->ctx_idr, request->ctx_id);
62968144	153	if (!map) {
30e2fb18	154	mutex_unlock(&dev->struct_mutex);
1da177e4 LT	155	return -EINVAL;
	156	}
	157
c153f45f	158	request->handle = NULL;
bd1b331f	159	list_for_each_entry(_entry, &dev->maplist, head) {
d1f2b55a	160	if (_entry->map == map) {
bc5f4523	161	request->handle =
b5e89ed5	162	(void *)(unsigned long)_entry->user_token;
d1f2b55a DA	163	break;
	164	}
	165	}
09b4ea47 IH	166
	167	mutex_unlock(&dev->struct_mutex);
	168
c153f45f	169	if (request->handle == NULL)
d1f2b55a DA	170	return -EINVAL;
d1f2b55a DA	171
1da177e4 LT	172	return 0;
	173	}
	174
	175	/**
	176	* Set per-context SAREA.
b5e89ed5	177	*
1da177e4	178	* \param inode device inode.
6c340eac	179	* \param file_priv DRM file private.
1da177e4 LT	180	* \param cmd command.
	181	* \param arg user argument pointing to a drm_ctx_priv_map structure.
	182	* \return zero on success or a negative number on failure.
	183	*
	184	* Searches the mapping specified in \p arg and update the entry in
62968144	185	* drm_device::ctx_idr with it.
1da177e4	186	*/
c153f45f EA	187	int drm_setsareactx(struct drm_device dev, void data,
c153f45f EA	188	struct drm_file *file_priv)
1da177e4	189	{
c153f45f	190	struct drm_ctx_priv_map *request = data;
f77d390c	191	struct drm_local_map *map = NULL;
55910517	192	struct drm_map_list *r_list = NULL;
1da177e4	193
30e2fb18	194	mutex_lock(&dev->struct_mutex);
bd1b331f	195	list_for_each_entry(r_list, &dev->maplist, head) {
9a186645	196	if (r_list->map
c153f45f	197	&& r_list->user_token == (unsigned long) request->handle)
1da177e4 LT	198	goto found;
1da177e4 LT	199	}
b5e89ed5	200	bad:
30e2fb18	201	mutex_unlock(&dev->struct_mutex);
1da177e4 LT	202	return -EINVAL;
1da177e4 LT	203
b5e89ed5	204	found:
1da177e4	205	map = r_list->map;
b5e89ed5 DA	206	if (!map)
b5e89ed5 DA	207	goto bad;
62968144	208
c153f45f	209	if (IS_ERR(idr_replace(&dev->ctx_idr, map, request->ctx_id)))
1da177e4	210	goto bad;
62968144	211
30e2fb18	212	mutex_unlock(&dev->struct_mutex);
c153f45f	213
1da177e4 LT	214	return 0;
	215	}
	216
	217	/@}/
	218
	219	/******************************************************************/
	220	/** \name The actual DRM context handling routines */
	221	/@{/
	222
	223	/**
	224	* Switch context.
	225	*
	226	* \param dev DRM device.
	227	* \param old old context handle.
	228	* \param new new context handle.
	229	* \return zero on success or a negative number on failure.
	230	*
	231	* Attempt to set drm_device::context_flag.
	232	*/
84b1fd10	233	static int drm_context_switch(struct drm_device * dev, int old, int new)
1da177e4	234	{
b5e89ed5 DA	235	if (test_and_set_bit(0, &dev->context_flag)) {
	236	DRM_ERROR("Reentering -- FIXME\n");
	237	return -EBUSY;
	238	}
1da177e4	239
b5e89ed5	240	DRM_DEBUG("Context switch from %d to %d\n", old, new);
1da177e4	241
b5e89ed5 DA	242	if (new == dev->last_context) {
	243	clear_bit(0, &dev->context_flag);
	244	return 0;
	245	}
1da177e4	246
b5e89ed5	247	return 0;
1da177e4 LT	248	}
	249
	250	/**
	251	* Complete context switch.
	252	*
	253	* \param dev DRM device.
	254	* \param new new context handle.
	255	* \return zero on success or a negative number on failure.
	256	*
	257	* Updates drm_device::last_context and drm_device::last_switch. Verifies the
	258	* hardware lock is held, clears the drm_device::context_flag and wakes up
	259	* drm_device::context_wait.
	260	*/
7c1c2871 DA	261	static int drm_context_switch_complete(struct drm_device *dev,
7c1c2871 DA	262	struct drm_file *file_priv, int new)
1da177e4	263	{
b5e89ed5 DA	264	dev->last_context = new; /* PRE/POST: This is the _only_ writer. */
b5e89ed5 DA	265	dev->last_switch = jiffies;
1da177e4	266
7c1c2871	267	if (!_DRM_LOCK_IS_HELD(file_priv->master->lock.hw_lock->lock)) {
b5e89ed5 DA	268	DRM_ERROR("Lock isn't held after context switch\n");
b5e89ed5 DA	269	}
1da177e4	270
b5e89ed5 DA	271	/* If a context switch is ever initiated
	272	when the kernel holds the lock, release
	273	that lock here. */
	274	clear_bit(0, &dev->context_flag);
	275	wake_up(&dev->context_wait);
1da177e4	276
b5e89ed5	277	return 0;
1da177e4 LT	278	}
	279
	280	/**
	281	* Reserve contexts.
	282	*
	283	* \param inode device inode.
6c340eac	284	* \param file_priv DRM file private.
1da177e4 LT	285	* \param cmd command.
	286	* \param arg user argument pointing to a drm_ctx_res structure.
	287	* \return zero on success or a negative number on failure.
	288	*/
c153f45f EA	289	int drm_resctx(struct drm_device dev, void data,
c153f45f EA	290	struct drm_file *file_priv)
1da177e4	291	{
c153f45f	292	struct drm_ctx_res *res = data;
c60ce623	293	struct drm_ctx ctx;
1da177e4 LT	294	int i;
1da177e4 LT	295
c153f45f	296	if (res->count >= DRM_RESERVED_CONTEXTS) {
b5e89ed5 DA	297	memset(&ctx, 0, sizeof(ctx));
b5e89ed5 DA	298	for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
1da177e4	299	ctx.handle = i;
c153f45f	300	if (copy_to_user(&res->contexts[i], &ctx, sizeof(ctx)))
1da177e4 LT	301	return -EFAULT;
	302	}
	303	}
c153f45f	304	res->count = DRM_RESERVED_CONTEXTS;
1da177e4	305
1da177e4 LT	306	return 0;
	307	}
	308
	309	/**
	310	* Add context.
	311	*
	312	* \param inode device inode.
6c340eac	313	* \param file_priv DRM file private.
1da177e4 LT	314	* \param cmd command.
	315	* \param arg user argument pointing to a drm_ctx structure.
	316	* \return zero on success or a negative number on failure.
	317	*
	318	* Get a new handle for the context and copy to userspace.
	319	*/
c153f45f EA	320	int drm_addctx(struct drm_device dev, void data,
c153f45f EA	321	struct drm_file *file_priv)
1da177e4	322	{
55910517	323	struct drm_ctx_list *ctx_entry;
c153f45f	324	struct drm_ctx *ctx = data;
1da177e4	325
c153f45f EA	326	ctx->handle = drm_ctxbitmap_next(dev);
c153f45f EA	327	if (ctx->handle == DRM_KERNEL_CONTEXT) {
b5e89ed5	328	/* Skip kernel's context and get a new one. */
c153f45f	329	ctx->handle = drm_ctxbitmap_next(dev);
1da177e4	330	}
c153f45f EA	331	DRM_DEBUG("%d\n", ctx->handle);
c153f45f EA	332	if (ctx->handle == -1) {
b5e89ed5 DA	333	DRM_DEBUG("Not enough free contexts.\n");
b5e89ed5 DA	334	/* Should this return -EBUSY instead? */
1da177e4 LT	335	return -ENOMEM;
	336	}
	337
9a298b2a	338	ctx_entry = kmalloc(sizeof(*ctx_entry), GFP_KERNEL);
b5e89ed5	339	if (!ctx_entry) {
1da177e4 LT	340	DRM_DEBUG("out of memory\n");
	341	return -ENOMEM;
	342	}
	343
b5e89ed5	344	INIT_LIST_HEAD(&ctx_entry->head);
c153f45f	345	ctx_entry->handle = ctx->handle;
6c340eac	346	ctx_entry->tag = file_priv;
1da177e4	347
30e2fb18	348	mutex_lock(&dev->ctxlist_mutex);
bd1b331f	349	list_add(&ctx_entry->head, &dev->ctxlist);
1da177e4	350	++dev->ctx_count;
30e2fb18	351	mutex_unlock(&dev->ctxlist_mutex);
1da177e4	352
1da177e4 LT	353	return 0;
	354	}
	355
c153f45f	356	int drm_modctx(struct drm_device dev, void data, struct drm_file *file_priv)
1da177e4 LT	357	{
	358	/* This does nothing */
	359	return 0;
	360	}
	361
	362	/**
	363	* Get context.
	364	*
	365	* \param inode device inode.
6c340eac	366	* \param file_priv DRM file private.
1da177e4 LT	367	* \param cmd command.
	368	* \param arg user argument pointing to a drm_ctx structure.
	369	* \return zero on success or a negative number on failure.
	370	*/
c153f45f	371	int drm_getctx(struct drm_device dev, void data, struct drm_file *file_priv)
1da177e4	372	{
c153f45f	373	struct drm_ctx *ctx = data;
1da177e4 LT	374
1da177e4 LT	375	/* This is 0, because we don't handle any context flags */
c153f45f	376	ctx->flags = 0;
1da177e4	377
1da177e4 LT	378	return 0;
	379	}
	380
	381	/**
	382	* Switch context.
	383	*
	384	* \param inode device inode.
6c340eac	385	* \param file_priv DRM file private.
1da177e4 LT	386	* \param cmd command.
	387	* \param arg user argument pointing to a drm_ctx structure.
	388	* \return zero on success or a negative number on failure.
	389	*
	390	* Calls context_switch().
	391	*/
c153f45f EA	392	int drm_switchctx(struct drm_device dev, void data,
c153f45f EA	393	struct drm_file *file_priv)
1da177e4	394	{
c153f45f	395	struct drm_ctx *ctx = data;
1da177e4	396
c153f45f EA	397	DRM_DEBUG("%d\n", ctx->handle);
c153f45f EA	398	return drm_context_switch(dev, dev->last_context, ctx->handle);
1da177e4 LT	399	}
	400
	401	/**
	402	* New context.
	403	*
	404	* \param inode device inode.
6c340eac	405	* \param file_priv DRM file private.
1da177e4 LT	406	* \param cmd command.
	407	* \param arg user argument pointing to a drm_ctx structure.
	408	* \return zero on success or a negative number on failure.
	409	*
	410	* Calls context_switch_complete().
	411	*/
c153f45f EA	412	int drm_newctx(struct drm_device dev, void data,
c153f45f EA	413	struct drm_file *file_priv)
1da177e4	414	{
c153f45f	415	struct drm_ctx *ctx = data;
1da177e4	416
c153f45f	417	DRM_DEBUG("%d\n", ctx->handle);
7c1c2871	418	drm_context_switch_complete(dev, file_priv, ctx->handle);
1da177e4 LT	419
	420	return 0;
	421	}
	422
	423	/**
	424	* Remove context.
	425	*
	426	* \param inode device inode.
6c340eac	427	* \param file_priv DRM file private.
1da177e4 LT	428	* \param cmd command.
	429	* \param arg user argument pointing to a drm_ctx structure.
	430	* \return zero on success or a negative number on failure.
	431	*
	432	* If not the special kernel context, calls ctxbitmap_free() to free the specified context.
	433	*/
c153f45f EA	434	int drm_rmctx(struct drm_device dev, void data,
c153f45f EA	435	struct drm_file *file_priv)
1da177e4	436	{
c153f45f	437	struct drm_ctx *ctx = data;
1da177e4	438
c153f45f	439	DRM_DEBUG("%d\n", ctx->handle);
c153f45f	440	if (ctx->handle != DRM_KERNEL_CONTEXT) {
1da177e4	441	if (dev->driver->context_dtor)
c153f45f EA	442	dev->driver->context_dtor(dev, ctx->handle);
c153f45f EA	443	drm_ctxbitmap_free(dev, ctx->handle);
1da177e4 LT	444	}
1da177e4 LT	445
30e2fb18	446	mutex_lock(&dev->ctxlist_mutex);
bd1b331f	447	if (!list_empty(&dev->ctxlist)) {
55910517	448	struct drm_ctx_list pos, n;
1da177e4	449
bd1b331f	450	list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
c153f45f	451	if (pos->handle == ctx->handle) {
b5e89ed5	452	list_del(&pos->head);
9a298b2a	453	kfree(pos);
1da177e4 LT	454	--dev->ctx_count;
	455	}
	456	}
	457	}
30e2fb18	458	mutex_unlock(&dev->ctxlist_mutex);
1da177e4 LT	459
	460	return 0;
	461	}
	462
	463	/@}/