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path: root/linux-core/drm_drv.c
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/**
 * \file drm_drv.c
 * Generic driver template
 *
 * \author Rickard E. (Rik) Faith <faith@valinux.com>
 * \author Gareth Hughes <gareth@valinux.com>
 *
 * To use this template, you must at least define the following (samples
 * given for the MGA driver):
 *
 * \code
 * #define DRIVER_AUTHOR	"VA Linux Systems, Inc."
 *
 * #define DRIVER_NAME		"mga"
 * #define DRIVER_DESC		"Matrox G200/G400"
 * #define DRIVER_DATE		"20001127"
 *
 * #define DRIVER_IOCTL_COUNT	DRM_ARRAY_SIZE( mga_ioctls )
 *
 * #define drm_x		mga_##x
 * \endcode
 */

/*
 * Created: Thu Nov 23 03:10:50 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.
 */
#include "drmP.h"
#include "drm_core.h"

static void __exit drm_cleanup(drm_device_t * dev);
int drm_fb_loaded = 0;

/** Ioctl table */
drm_ioctl_desc_t drm_ioctls[] = {
	[DRM_IOCTL_NR(DRM_IOCTL_VERSION)] = {drm_version, 0, 0},
	[DRM_IOCTL_NR(DRM_IOCTL_GET_UNIQUE)] = {drm_getunique, 0, 0},
	[DRM_IOCTL_NR(DRM_IOCTL_GET_MAGIC)] = {drm_getmagic, 0, 0},
	[DRM_IOCTL_NR(DRM_IOCTL_IRQ_BUSID)] = {drm_irq_by_busid, 0, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_GET_MAP)] = {drm_getmap, 0, 0},
	[DRM_IOCTL_NR(DRM_IOCTL_GET_CLIENT)] = {drm_getclient, 0, 0},
	[DRM_IOCTL_NR(DRM_IOCTL_GET_STATS)] = {drm_getstats, 0, 0},
	[DRM_IOCTL_NR(DRM_IOCTL_SET_VERSION)] = {drm_setversion, 0, 1},

	[DRM_IOCTL_NR(DRM_IOCTL_SET_UNIQUE)] = {drm_setunique, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_BLOCK)] = {drm_noop, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_UNBLOCK)] = {drm_noop, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_AUTH_MAGIC)] = {drm_authmagic, 1, 1},

	[DRM_IOCTL_NR(DRM_IOCTL_ADD_MAP)] = {drm_addmap, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_RM_MAP)] = {drm_rmmap, 1, 0},

	[DRM_IOCTL_NR(DRM_IOCTL_SET_SAREA_CTX)] = {drm_setsareactx, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_GET_SAREA_CTX)] = {drm_getsareactx, 1, 0},

	[DRM_IOCTL_NR(DRM_IOCTL_ADD_CTX)] = {drm_addctx, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_RM_CTX)] = {drm_rmctx, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_MOD_CTX)] = {drm_modctx, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_GET_CTX)] = {drm_getctx, 1, 0},
	[DRM_IOCTL_NR(DRM_IOCTL_SWITCH_CTX)] = {drm_switchctx, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_NEW_CTX)] = {drm_newctx, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_RES_CTX)] = {drm_resctx, 1, 0},

	[DRM_IOCTL_NR(DRM_IOCTL_ADD_DRAW)] = {drm_adddraw, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_RM_DRAW)] = {drm_rmdraw, 1, 1},

	[DRM_IOCTL_NR(DRM_IOCTL_LOCK)] = {drm_lock, 1, 0},
	[DRM_IOCTL_NR(DRM_IOCTL_UNLOCK)] = {drm_unlock, 1, 0},

	[DRM_IOCTL_NR(DRM_IOCTL_FINISH)] = {drm_noop, 1, 0},

	[DRM_IOCTL_NR(DRM_IOCTL_ADD_BUFS)] = {drm_addbufs, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_MARK_BUFS)] = {drm_markbufs, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_INFO_BUFS)] = {drm_infobufs, 1, 0},
	[DRM_IOCTL_NR(DRM_IOCTL_MAP_BUFS)] = {drm_mapbufs, 1, 0},
	[DRM_IOCTL_NR(DRM_IOCTL_FREE_BUFS)] = {drm_freebufs, 1, 0},
	/* The DRM_IOCTL_DMA ioctl should be defined by the driver. */
	[DRM_IOCTL_NR(DRM_IOCTL_DMA)] = {NULL, 1, 0},

	[DRM_IOCTL_NR(DRM_IOCTL_CONTROL)] = {drm_control, 1, 1},

#if __OS_HAS_AGP
	[DRM_IOCTL_NR(DRM_IOCTL_AGP_ACQUIRE)] = {drm_agp_acquire, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_AGP_RELEASE)] = {drm_agp_release, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_AGP_ENABLE)] = {drm_agp_enable, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_AGP_INFO)] = {drm_agp_info, 1, 0},
	[DRM_IOCTL_NR(DRM_IOCTL_AGP_ALLOC)] = {drm_agp_alloc, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_AGP_FREE)] = {drm_agp_free, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_AGP_BIND)] = {drm_agp_bind, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_AGP_UNBIND)] = {drm_agp_unbind, 1, 1},
#endif

	[DRM_IOCTL_NR(DRM_IOCTL_SG_ALLOC)] = {drm_sg_alloc, 1, 1},
	[DRM_IOCTL_NR(DRM_IOCTL_SG_FREE)] = {drm_sg_free, 1, 1},

	[DRM_IOCTL_NR(DRM_IOCTL_WAIT_VBLANK)] = {drm_wait_vblank, 0, 0},
};

#define DRIVER_IOCTL_COUNT	DRM_ARRAY_SIZE( drm_ioctls )

/**
 * Take down the DRM device.
 *
 * \param dev DRM device structure.
 *
 * Frees every resource in \p dev.
 *
 * \sa drm_device and setup().
 */
int drm_takedown(drm_device_t * dev)
{
	drm_magic_entry_t *pt, *next;
	drm_map_t *map;
	drm_map_list_t *r_list;
	struct list_head *list, *list_next;
	drm_vma_entry_t *vma, *vma_next;
	int i;

	DRM_DEBUG("\n");

	if (dev->driver->pretakedown)
		dev->driver->pretakedown(dev);

	if (dev->unique) {
		drm_free(dev->unique, strlen(dev->unique) + 1, DRM_MEM_DRIVER);
		dev->unique=NULL;
		dev->unique_len=0;
	}

	if (dev->irq_enabled)
		drm_irq_uninstall(dev);

	down(&dev->struct_sem);
	del_timer(&dev->timer);

	if (dev->unique) {
		drm_free(dev->unique, strlen(dev->unique) + 1, DRM_MEM_DRIVER);
		dev->unique = NULL;
		dev->unique_len = 0;
	}

	/* Clear pid list */
	for (i = 0; i < DRM_HASH_SIZE; i++) {
		for (pt = dev->magiclist[i].head; pt; pt = next) {
			next = pt->next;
			drm_free(pt, sizeof(*pt), DRM_MEM_MAGIC);
		}
		dev->magiclist[i].head = dev->magiclist[i].tail = NULL;
	}

	/* Clear AGP information */
	if (drm_core_has_AGP(dev) && dev->agp) {
		drm_agp_mem_t *entry;
		drm_agp_mem_t *nexte;

		/* Remove AGP resources, but leave dev->agp
		   intact until drv_cleanup is called. */
		for (entry = dev->agp->memory; entry; entry = nexte) {
			nexte = entry->next;
			if (entry->bound)
				drm_unbind_agp(entry->memory);
			drm_free_agp(entry->memory, entry->pages);
			drm_free(entry, sizeof(*entry), DRM_MEM_AGPLISTS);
		}
		dev->agp->memory = NULL;

		if (dev->agp->acquired)
			drm_agp_do_release(dev);

		dev->agp->acquired = 0;
		dev->agp->enabled = 0;
	}

	/* Clear vma list (only built for debugging) */
	if (dev->vmalist) {
		for (vma = dev->vmalist; vma; vma = vma_next) {
			vma_next = vma->next;
			drm_free(vma, sizeof(*vma), DRM_MEM_VMAS);
		}
		dev->vmalist = NULL;
	}

	if (dev->maplist) {
		list_for_each_safe(list, list_next, &dev->maplist->head) {
			r_list = (drm_map_list_t *) list;

			if ((map = r_list->map)) {
				switch (map->type) {
				case _DRM_REGISTERS:
				case _DRM_FRAME_BUFFER:
					continue;

				case _DRM_SHM:
					vfree(map->handle);
					break;

				case _DRM_AGP:
					/* Do nothing here, because this is all
					 * handled in the AGP/GART driver.
					 */
					break;
				case _DRM_SCATTER_GATHER:
					/* Handle it */
					if (drm_core_check_feature
					    (dev, DRIVER_SG) && dev->sg) {
						drm_sg_cleanup(dev->sg);
						dev->sg = NULL;
					}
					break;
				case _DRM_CONSISTENT:
					drm_pci_free(dev, map->size,
						     map->handle, map->offset);
					break;
				}
				drm_free(map, sizeof(*map), DRM_MEM_MAPS);
			}
			list_del(list);
			drm_free(r_list, sizeof(*r_list), DRM_MEM_MAPS);
		}
	}

	if (drm_core_check_feature(dev, DRIVER_DMA_QUEUE) && dev->queuelist) {
		for (i = 0; i < dev->queue_count; i++) {

			if (dev->queuelist[i]) {
				drm_free(dev->queuelist[i],
					 sizeof(*dev->queuelist[0]),
					 DRM_MEM_QUEUES);
				dev->queuelist[i] = NULL;
			}
		}
		drm_free(dev->queuelist,
			 dev->queue_slots * sizeof(*dev->queuelist),
			 DRM_MEM_QUEUES);
		dev->queuelist = NULL;
	}
	dev->queue_count = 0;

	if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
		drm_dma_takedown(dev);

	if (dev->lock.hw_lock) {
		dev->sigdata.lock = dev->lock.hw_lock = NULL;	/* SHM removed */
		dev->lock.filp = NULL;
		wake_up_interruptible(&dev->lock.lock_queue);
	}
	up(&dev->struct_sem);

	return 0;
}

void __exit drm_cleanup_pci(struct pci_dev *pdev)
{
	drm_device_t *dev = pci_get_drvdata(pdev);

	pci_set_drvdata(pdev, NULL);
	pci_release_regions(pdev);
	if (dev)
		drm_cleanup(dev);
}
EXPORT_SYMBOL(drm_cleanup_pci);

/**
 * Module initialization. Called via init_module at module load time, or via
 * linux/init/main.c (this is not currently supported).
 *
 * \return zero on success or a negative number on failure.
 *
 * Initializes an array of drm_device structures, and attempts to
 * initialize all available devices, using consecutive minors, registering the
 * stubs and initializing the AGP device.
 *
 * Expands the \c DRIVER_PREINIT and \c DRIVER_POST_INIT macros before and
 * after the initialization for driver customization.
 */
int drm_init(struct drm_driver *driver,
		       struct pci_device_id *pciidlist)
{
	struct pci_dev *pdev;
	struct pci_device_id *pid;
	int i;

	DRM_DEBUG("\n");

	drm_mem_init();

	for (i = 0; (pciidlist[i].vendor != 0) && !drm_fb_loaded; i++) {
		pid = &pciidlist[i];

		pdev = NULL;
		/* pass back in pdev to account for multiple identical cards */
		while ((pdev =
			pci_get_subsys(pid->vendor, pid->device, pid->subvendor,
				       pid->subdevice, pdev))) {
			/* is there already a driver loaded, or (short circuit saves work) */
			/* does something like VesaFB have control of the memory region? */
			if (pci_dev_driver(pdev)
			    || pci_request_regions(pdev, "DRM scan")) {
				/* go into stealth mode */
				drm_fb_loaded = 1;
				pci_dev_put(pdev);
				break;
			}
			/* no fbdev or vesadev, put things back and wait for normal probe */
			pci_release_regions(pdev);
		}
	}

	if (drm_fb_loaded == 0)
		pci_register_driver(&driver->pci_driver);
	else {
		for (i = 0; pciidlist[i].vendor != 0; i++) {
			pid = &pciidlist[i];

			pdev = NULL;
			/* pass back in pdev to account for multiple identical cards */
			while ((pdev =
				pci_get_subsys(pid->vendor, pid->device,
					       pid->subvendor, pid->subdevice,
					       pdev))) {
				/* stealth mode requires a manual probe */
				pci_dev_get(pdev);
				drm_get_dev(pdev, &pciidlist[i], driver);
			}
		}
		DRM_INFO("Used old pci detect: framebuffer loaded\n");
	}
	return 0;
}
EXPORT_SYMBOL(drm_init);

/**
 * Called via cleanup_module() at module unload time.
 *
 * Cleans up all DRM device, calling takedown().
 *
 * \sa drm_init().
 */
static void __exit drm_cleanup(drm_device_t * dev)
{
	drm_map_t *map;
	drm_map_list_t *r_list;
	struct list_head *list, *list_next;

	DRM_DEBUG("\n");
	if (!dev) {
		DRM_ERROR("cleanup called no dev\n");
		return;
	}

	drm_takedown(dev);

	if (dev->maplist) {
		list_for_each_safe(list, list_next, &dev->maplist->head) {
			r_list = (drm_map_list_t *) list;

			if ((map = r_list->map)) {
				switch (map->type) {
				case _DRM_REGISTERS:
					drm_ioremapfree(map->handle, map->size,
							dev);
					break;

				case _DRM_FRAME_BUFFER:
					if (drm_core_has_MTRR(dev)) {
						if (map->mtrr >= 0) {
							int retcode;
							retcode =
							    mtrr_del(map->mtrr,
								     map->
								     offset,
								     map->size);
							DRM_DEBUG
							    ("mtrr_del=%d\n",
							     retcode);
						}
					}
					break;

				case _DRM_SHM:
				case _DRM_AGP:
				case _DRM_SCATTER_GATHER:
				case _DRM_CONSISTENT:
					DRM_DEBUG("Extra maplist item\n");
					break;
				}
				drm_free(map, sizeof(*map), DRM_MEM_MAPS);
			}
			list_del(list);
			drm_free(r_list, sizeof(*r_list), DRM_MEM_MAPS);
		}
		drm_free(dev->maplist, sizeof(*dev->maplist), DRM_MEM_MAPS);
		dev->maplist = NULL;
	}
	if (drm_fb_loaded == 0)
		pci_disable_device(dev->pdev);

	drm_ctxbitmap_cleanup(dev);

	if (drm_core_has_MTRR(dev) && drm_core_has_AGP(dev) && dev->agp
	    && dev->agp->agp_mtrr >= 0) {
		int retval;
		retval = mtrr_del(dev->agp->agp_mtrr,
				  dev->agp->agp_info.aper_base,
				  dev->agp->agp_info.aper_size * 1024 * 1024);
		DRM_DEBUG("mtrr_del=%d\n", retval);
	}

	if (drm_core_has_AGP(dev) && dev->agp) {
		drm_free(dev->agp, sizeof(*dev->agp), DRM_MEM_AGPLISTS);
		dev->agp = NULL;
	}
	if (dev->driver->postcleanup)
		dev->driver->postcleanup(dev);

	drm_put_head(&dev->primary);
	if (drm_put_dev(dev))
		DRM_ERROR("Cannot unload module\n");
}

void __exit drm_exit(struct drm_driver *driver)
{
	int i;
	drm_device_t *dev = NULL;
	drm_head_t *head;

	DRM_DEBUG("\n");
	if (drm_fb_loaded) {
		for (i = 0; i < cards_limit; i++) {
			head = drm_heads[i];
			if (!head)
				continue;
			if (!head->dev)
				continue;
			if (head->dev->driver != driver)
				continue;
			dev = head->dev;
		}
		if (dev) {
			/* release the pci driver */
			if (dev->pdev)
				pci_dev_put(dev->pdev);
			drm_cleanup(dev);
		}
	} else
		pci_unregister_driver(&driver->pci_driver);
	DRM_INFO("Module unloaded\n");
}
EXPORT_SYMBOL(drm_exit);

/** File operations structure */
static struct file_operations drm_stub_fops = {
	.owner = THIS_MODULE,
	.open = drm_stub_open
};

static int __init drm_core_init(void)
{
	int ret = -ENOMEM;

	cards_limit =
	    (cards_limit < DRM_MAX_MINOR + 1 ? cards_limit : DRM_MAX_MINOR + 1);
	drm_heads = drm_calloc(cards_limit, sizeof(*drm_heads), DRM_MEM_STUB);
	if (!drm_heads)
		goto err_p1;

	if (register_chrdev(DRM_MAJOR, "drm", &drm_stub_fops))
		goto err_p1;

	drm_class = drm_sysfs_create(THIS_MODULE, "drm");
	if (IS_ERR(drm_class)) {
		printk(KERN_ERR "DRM: Error creating drm class.\n");
		ret = PTR_ERR(drm_class);
		goto err_p2;
	}

	drm_proc_root = create_proc_entry("dri", S_IFDIR, NULL);
	if (!drm_proc_root) {
		DRM_ERROR("Cannot create /proc/dri\n");
		ret = -1;
		goto err_p3;
	}

	DRM_INFO("Initialized %s %d.%d.%d %s\n",
		 CORE_NAME,
		 CORE_MAJOR, CORE_MINOR, CORE_PATCHLEVEL, CORE_DATE);
	return 0;
err_p3:
	drm_sysfs_destroy(drm_class);
err_p2:
	unregister_chrdev(DRM_MAJOR, "drm");
	drm_free(drm_heads, sizeof(*drm_heads) * cards_limit, DRM_MEM_STUB);
err_p1:
	return ret;
}

static void __exit drm_core_exit(void)
{
	remove_proc_entry("dri", NULL);
	drm_sysfs_destroy(drm_class);

	unregister_chrdev(DRM_MAJOR, "drm");

	drm_free(drm_heads, sizeof(*drm_heads) * cards_limit, DRM_MEM_STUB);
}

module_init(drm_core_init);
module_exit(drm_core_exit);

/**
 * Get version information
 *
 * \param inode device inode.
 * \param filp file pointer.
 * \param cmd command.
 * \param arg user argument, pointing to a drm_version structure.
 * \return zero on success or negative number on failure.
 *
 * Fills in the version information in \p arg.
 */
int drm_version(struct inode *inode, struct file *filp,
		unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->head->dev;
	drm_version_t __user *argp = (void __user *)arg;
	drm_version_t version;
	int ret;

	if (copy_from_user(&version, argp, sizeof(version)))
		return -EFAULT;

	/* version is a required function to return the personality module version */
	if ((ret = dev->driver->version(&version)))
		return ret;

	if (copy_to_user(argp, &version, sizeof(version)))
		return -EFAULT;
	return 0;
}

/**
 * Called whenever a process performs an ioctl on /dev/drm.
 *
 * \param inode device inode.
 * \param filp file pointer.
 * \param cmd command.
 * \param arg user argument.
 * \return zero on success or negative number on failure.
 *
 * Looks up the ioctl function in the ::ioctls table, checking for root
 * previleges if so required, and dispatches to the respective function.
 */
int drm_ioctl(struct inode *inode, struct file *filp,
	      unsigned int cmd, unsigned long arg)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->head->dev;
	drm_ioctl_desc_t *ioctl;
	drm_ioctl_t *func;
	unsigned int nr = DRM_IOCTL_NR(cmd);
	int retcode = -EINVAL;

	atomic_inc(&dev->ioctl_count);
	atomic_inc(&dev->counts[_DRM_STAT_IOCTLS]);
	++priv->ioctl_count;

	DRM_DEBUG("pid=%d, cmd=0x%02x, nr=0x%02x, dev 0x%lx, auth=%d\n",
		  current->pid, cmd, nr, (long)old_encode_dev(priv->head->device),
		  priv->authenticated);

	if (nr < DRIVER_IOCTL_COUNT)
		ioctl = &drm_ioctls[nr];
	else if ((nr >= DRM_COMMAND_BASE)
		 && (nr < DRM_COMMAND_BASE + dev->driver->num_ioctls))
		ioctl = &dev->driver->ioctls[nr - DRM_COMMAND_BASE];
	else
		goto err_i1;

	func = ioctl->func;
	if ((nr == DRM_IOCTL_NR(DRM_IOCTL_DMA)) && dev->driver->dma_ioctl)	/* Local override? */
		func = dev->driver->dma_ioctl;

	if (!func) {
		DRM_DEBUG("no function\n");
		retcode = -EINVAL;
	} else if ((ioctl->root_only && !capable(CAP_SYS_ADMIN)) ||
		   (ioctl->auth_needed && !priv->authenticated)) {
		retcode = -EACCES;
	} else {
		retcode = func(inode, filp, cmd, arg);
	}
      err_i1:
	atomic_dec(&dev->ioctl_count);
	if (retcode)
		DRM_DEBUG("ret = %x\n", retcode);
	return retcode;
}
EXPORT_SYMBOL(drm_ioctl);