| /** | 
 |  * \file drm_fops.c | 
 |  * File operations for DRM | 
 |  * | 
 |  * \author Rickard E. (Rik) Faith <faith@valinux.com> | 
 |  * \author Daryll Strauss <daryll@valinux.com> | 
 |  * \author Gareth Hughes <gareth@valinux.com> | 
 |  */ | 
 |  | 
 | /* | 
 |  * Created: Mon Jan  4 08:58:31 1999 by faith@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 | 
 |  * 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_sarea.h" | 
 | #include <linux/poll.h> | 
 |  | 
 | static int drm_open_helper(struct inode *inode, struct file *filp, | 
 | 			   drm_device_t * dev); | 
 |  | 
 | static int drm_setup(drm_device_t * dev) | 
 | { | 
 | 	drm_local_map_t *map; | 
 | 	int i; | 
 | 	int ret; | 
 |  | 
 | 	if (dev->driver->firstopen) { | 
 | 		ret = dev->driver->firstopen(dev); | 
 | 		if (ret != 0) | 
 | 			return ret; | 
 | 	} | 
 |  | 
 | 	dev->magicfree.next = NULL; | 
 |  | 
 | 	/* prebuild the SAREA */ | 
 | 	i = drm_addmap(dev, 0, SAREA_MAX, _DRM_SHM, _DRM_CONTAINS_LOCK, &map); | 
 | 	if (i != 0) | 
 | 		return i; | 
 |  | 
 | 	atomic_set(&dev->ioctl_count, 0); | 
 | 	atomic_set(&dev->vma_count, 0); | 
 | 	dev->buf_use = 0; | 
 | 	atomic_set(&dev->buf_alloc, 0); | 
 |  | 
 | 	if (drm_core_check_feature(dev, DRIVER_HAVE_DMA)) { | 
 | 		i = drm_dma_setup(dev); | 
 | 		if (i < 0) | 
 | 			return i; | 
 | 	} | 
 |  | 
 | 	for (i = 0; i < ARRAY_SIZE(dev->counts); i++) | 
 | 		atomic_set(&dev->counts[i], 0); | 
 |  | 
 | 	drm_ht_create(&dev->magiclist, DRM_MAGIC_HASH_ORDER); | 
 | 	INIT_LIST_HEAD(&dev->magicfree); | 
 |  | 
 | 	dev->ctxlist = drm_alloc(sizeof(*dev->ctxlist), DRM_MEM_CTXLIST); | 
 | 	if (dev->ctxlist == NULL) | 
 | 		return -ENOMEM; | 
 | 	memset(dev->ctxlist, 0, sizeof(*dev->ctxlist)); | 
 | 	INIT_LIST_HEAD(&dev->ctxlist->head); | 
 |  | 
 | 	dev->vmalist = NULL; | 
 | 	dev->sigdata.lock = dev->lock.hw_lock = NULL; | 
 | 	init_waitqueue_head(&dev->lock.lock_queue); | 
 | 	dev->queue_count = 0; | 
 | 	dev->queue_reserved = 0; | 
 | 	dev->queue_slots = 0; | 
 | 	dev->queuelist = NULL; | 
 | 	dev->irq_enabled = 0; | 
 | 	dev->context_flag = 0; | 
 | 	dev->interrupt_flag = 0; | 
 | 	dev->dma_flag = 0; | 
 | 	dev->last_context = 0; | 
 | 	dev->last_switch = 0; | 
 | 	dev->last_checked = 0; | 
 | 	init_waitqueue_head(&dev->context_wait); | 
 | 	dev->if_version = 0; | 
 |  | 
 | 	dev->ctx_start = 0; | 
 | 	dev->lck_start = 0; | 
 |  | 
 | 	dev->buf_async = NULL; | 
 | 	init_waitqueue_head(&dev->buf_readers); | 
 | 	init_waitqueue_head(&dev->buf_writers); | 
 |  | 
 | 	DRM_DEBUG("\n"); | 
 |  | 
 | 	/* | 
 | 	 * The kernel's context could be created here, but is now created | 
 | 	 * in drm_dma_enqueue.  This is more resource-efficient for | 
 | 	 * hardware that does not do DMA, but may mean that | 
 | 	 * drm_select_queue fails between the time the interrupt is | 
 | 	 * initialized and the time the queues are initialized. | 
 | 	 */ | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | /** | 
 |  * Open file. | 
 |  * | 
 |  * \param inode device inode | 
 |  * \param filp file pointer. | 
 |  * \return zero on success or a negative number on failure. | 
 |  * | 
 |  * Searches the DRM device with the same minor number, calls open_helper(), and | 
 |  * increments the device open count. If the open count was previous at zero, | 
 |  * i.e., it's the first that the device is open, then calls setup(). | 
 |  */ | 
 | int drm_open(struct inode *inode, struct file *filp) | 
 | { | 
 | 	drm_device_t *dev = NULL; | 
 | 	int minor = iminor(inode); | 
 | 	int retcode = 0; | 
 |  | 
 | 	if (!((minor >= 0) && (minor < drm_cards_limit))) | 
 | 		return -ENODEV; | 
 |  | 
 | 	if (!drm_heads[minor]) | 
 | 		return -ENODEV; | 
 |  | 
 | 	if (!(dev = drm_heads[minor]->dev)) | 
 | 		return -ENODEV; | 
 |  | 
 | 	retcode = drm_open_helper(inode, filp, dev); | 
 | 	if (!retcode) { | 
 | 		atomic_inc(&dev->counts[_DRM_STAT_OPENS]); | 
 | 		spin_lock(&dev->count_lock); | 
 | 		if (!dev->open_count++) { | 
 | 			spin_unlock(&dev->count_lock); | 
 | 			return drm_setup(dev); | 
 | 		} | 
 | 		spin_unlock(&dev->count_lock); | 
 | 	} | 
 |  | 
 | 	return retcode; | 
 | } | 
 | EXPORT_SYMBOL(drm_open); | 
 |  | 
 | /** | 
 |  * File \c open operation. | 
 |  * | 
 |  * \param inode device inode. | 
 |  * \param filp file pointer. | 
 |  * | 
 |  * Puts the dev->fops corresponding to the device minor number into | 
 |  * \p filp, call the \c open method, and restore the file operations. | 
 |  */ | 
 | int drm_stub_open(struct inode *inode, struct file *filp) | 
 | { | 
 | 	drm_device_t *dev = NULL; | 
 | 	int minor = iminor(inode); | 
 | 	int err = -ENODEV; | 
 | 	const struct file_operations *old_fops; | 
 |  | 
 | 	DRM_DEBUG("\n"); | 
 |  | 
 | 	if (!((minor >= 0) && (minor < drm_cards_limit))) | 
 | 		return -ENODEV; | 
 |  | 
 | 	if (!drm_heads[minor]) | 
 | 		return -ENODEV; | 
 |  | 
 | 	if (!(dev = drm_heads[minor]->dev)) | 
 | 		return -ENODEV; | 
 |  | 
 | 	old_fops = filp->f_op; | 
 | 	filp->f_op = fops_get(&dev->driver->fops); | 
 | 	if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) { | 
 | 		fops_put(filp->f_op); | 
 | 		filp->f_op = fops_get(old_fops); | 
 | 	} | 
 | 	fops_put(old_fops); | 
 |  | 
 | 	return err; | 
 | } | 
 |  | 
 | /** | 
 |  * Check whether DRI will run on this CPU. | 
 |  * | 
 |  * \return non-zero if the DRI will run on this CPU, or zero otherwise. | 
 |  */ | 
 | static int drm_cpu_valid(void) | 
 | { | 
 | #if defined(__i386__) | 
 | 	if (boot_cpu_data.x86 == 3) | 
 | 		return 0;	/* No cmpxchg on a 386 */ | 
 | #endif | 
 | #if defined(__sparc__) && !defined(__sparc_v9__) | 
 | 	return 0;		/* No cmpxchg before v9 sparc. */ | 
 | #endif | 
 | 	return 1; | 
 | } | 
 |  | 
 | /** | 
 |  * Called whenever a process opens /dev/drm. | 
 |  * | 
 |  * \param inode device inode. | 
 |  * \param filp file pointer. | 
 |  * \param dev device. | 
 |  * \return zero on success or a negative number on failure. | 
 |  * | 
 |  * Creates and initializes a drm_file structure for the file private data in \p | 
 |  * filp and add it into the double linked list in \p dev. | 
 |  */ | 
 | static int drm_open_helper(struct inode *inode, struct file *filp, | 
 | 			   drm_device_t * dev) | 
 | { | 
 | 	int minor = iminor(inode); | 
 | 	drm_file_t *priv; | 
 | 	int ret; | 
 |  | 
 | 	if (filp->f_flags & O_EXCL) | 
 | 		return -EBUSY;	/* No exclusive opens */ | 
 | 	if (!drm_cpu_valid()) | 
 | 		return -EINVAL; | 
 |  | 
 | 	DRM_DEBUG("pid = %d, minor = %d\n", current->pid, minor); | 
 |  | 
 | 	priv = drm_alloc(sizeof(*priv), DRM_MEM_FILES); | 
 | 	if (!priv) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	memset(priv, 0, sizeof(*priv)); | 
 | 	filp->private_data = priv; | 
 | 	priv->uid = current->euid; | 
 | 	priv->pid = current->pid; | 
 | 	priv->minor = minor; | 
 | 	priv->head = drm_heads[minor]; | 
 | 	priv->ioctl_count = 0; | 
 | 	/* for compatibility root is always authenticated */ | 
 | 	priv->authenticated = capable(CAP_SYS_ADMIN); | 
 | 	priv->lock_count = 0; | 
 |  | 
 | 	if (dev->driver->open) { | 
 | 		ret = dev->driver->open(dev, priv); | 
 | 		if (ret < 0) | 
 | 			goto out_free; | 
 | 	} | 
 |  | 
 | 	mutex_lock(&dev->struct_mutex); | 
 | 	if (!dev->file_last) { | 
 | 		priv->next = NULL; | 
 | 		priv->prev = NULL; | 
 | 		dev->file_first = priv; | 
 | 		dev->file_last = priv; | 
 | 		/* first opener automatically becomes master */ | 
 | 		priv->master = 1; | 
 | 	} else { | 
 | 		priv->next = NULL; | 
 | 		priv->prev = dev->file_last; | 
 | 		dev->file_last->next = priv; | 
 | 		dev->file_last = priv; | 
 | 	} | 
 | 	mutex_unlock(&dev->struct_mutex); | 
 |  | 
 | #ifdef __alpha__ | 
 | 	/* | 
 | 	 * Default the hose | 
 | 	 */ | 
 | 	if (!dev->hose) { | 
 | 		struct pci_dev *pci_dev; | 
 | 		pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL); | 
 | 		if (pci_dev) { | 
 | 			dev->hose = pci_dev->sysdata; | 
 | 			pci_dev_put(pci_dev); | 
 | 		} | 
 | 		if (!dev->hose) { | 
 | 			struct pci_bus *b = pci_bus_b(pci_root_buses.next); | 
 | 			if (b) | 
 | 				dev->hose = b->sysdata; | 
 | 		} | 
 | 	} | 
 | #endif | 
 |  | 
 | 	return 0; | 
 |       out_free: | 
 | 	drm_free(priv, sizeof(*priv), DRM_MEM_FILES); | 
 | 	filp->private_data = NULL; | 
 | 	return ret; | 
 | } | 
 |  | 
 | /** No-op. */ | 
 | int drm_fasync(int fd, struct file *filp, int on) | 
 | { | 
 | 	drm_file_t *priv = filp->private_data; | 
 | 	drm_device_t *dev = priv->head->dev; | 
 | 	int retcode; | 
 |  | 
 | 	DRM_DEBUG("fd = %d, device = 0x%lx\n", fd, | 
 | 		  (long)old_encode_dev(priv->head->device)); | 
 | 	retcode = fasync_helper(fd, filp, on, &dev->buf_async); | 
 | 	if (retcode < 0) | 
 | 		return retcode; | 
 | 	return 0; | 
 | } | 
 | EXPORT_SYMBOL(drm_fasync); | 
 |  | 
 | /** | 
 |  * Release file. | 
 |  * | 
 |  * \param inode device inode | 
 |  * \param filp file pointer. | 
 |  * \return zero on success or a negative number on failure. | 
 |  * | 
 |  * If the hardware lock is held then free it, and take it again for the kernel | 
 |  * context since it's necessary to reclaim buffers. Unlink the file private | 
 |  * data from its list and free it. Decreases the open count and if it reaches | 
 |  * zero calls drm_lastclose(). | 
 |  */ | 
 | int drm_release(struct inode *inode, struct file *filp) | 
 | { | 
 | 	drm_file_t *priv = filp->private_data; | 
 | 	drm_device_t *dev; | 
 | 	int retcode = 0; | 
 |  | 
 | 	lock_kernel(); | 
 | 	dev = priv->head->dev; | 
 |  | 
 | 	DRM_DEBUG("open_count = %d\n", dev->open_count); | 
 |  | 
 | 	if (dev->driver->preclose) | 
 | 		dev->driver->preclose(dev, filp); | 
 |  | 
 | 	/* ======================================================== | 
 | 	 * Begin inline drm_release | 
 | 	 */ | 
 |  | 
 | 	DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n", | 
 | 		  current->pid, (long)old_encode_dev(priv->head->device), | 
 | 		  dev->open_count); | 
 |  | 
 | 	if (priv->lock_count && dev->lock.hw_lock && | 
 | 	    _DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock) && | 
 | 	    dev->lock.filp == filp) { | 
 | 		DRM_DEBUG("File %p released, freeing lock for context %d\n", | 
 | 			  filp, _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock)); | 
 |  | 
 | 		if (dev->driver->reclaim_buffers_locked) | 
 | 			dev->driver->reclaim_buffers_locked(dev, filp); | 
 |  | 
 | 		drm_lock_free(dev, &dev->lock.hw_lock->lock, | 
 | 			      _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock)); | 
 |  | 
 | 		/* FIXME: may require heavy-handed reset of | 
 | 		   hardware at this point, possibly | 
 | 		   processed via a callback to the X | 
 | 		   server. */ | 
 | 	} else if (dev->driver->reclaim_buffers_locked && priv->lock_count | 
 | 		   && dev->lock.hw_lock) { | 
 | 		/* The lock is required to reclaim buffers */ | 
 | 		DECLARE_WAITQUEUE(entry, current); | 
 |  | 
 | 		add_wait_queue(&dev->lock.lock_queue, &entry); | 
 | 		for (;;) { | 
 | 			__set_current_state(TASK_INTERRUPTIBLE); | 
 | 			if (!dev->lock.hw_lock) { | 
 | 				/* Device has been unregistered */ | 
 | 				retcode = -EINTR; | 
 | 				break; | 
 | 			} | 
 | 			if (drm_lock_take(&dev->lock.hw_lock->lock, | 
 | 					  DRM_KERNEL_CONTEXT)) { | 
 | 				dev->lock.filp = filp; | 
 | 				dev->lock.lock_time = jiffies; | 
 | 				atomic_inc(&dev->counts[_DRM_STAT_LOCKS]); | 
 | 				break;	/* Got lock */ | 
 | 			} | 
 | 			/* Contention */ | 
 | 			schedule(); | 
 | 			if (signal_pending(current)) { | 
 | 				retcode = -ERESTARTSYS; | 
 | 				break; | 
 | 			} | 
 | 		} | 
 | 		__set_current_state(TASK_RUNNING); | 
 | 		remove_wait_queue(&dev->lock.lock_queue, &entry); | 
 | 		if (!retcode) { | 
 | 			dev->driver->reclaim_buffers_locked(dev, filp); | 
 | 			drm_lock_free(dev, &dev->lock.hw_lock->lock, | 
 | 				      DRM_KERNEL_CONTEXT); | 
 | 		} | 
 | 	} | 
 |  | 
 | 	if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) && | 
 | 	    !dev->driver->reclaim_buffers_locked) { | 
 | 		dev->driver->reclaim_buffers(dev, filp); | 
 | 	} | 
 |  | 
 | 	drm_fasync(-1, filp, 0); | 
 |  | 
 | 	mutex_lock(&dev->ctxlist_mutex); | 
 | 	if (dev->ctxlist && (!list_empty(&dev->ctxlist->head))) { | 
 | 		drm_ctx_list_t *pos, *n; | 
 |  | 
 | 		list_for_each_entry_safe(pos, n, &dev->ctxlist->head, head) { | 
 | 			if (pos->tag == priv && | 
 | 			    pos->handle != DRM_KERNEL_CONTEXT) { | 
 | 				if (dev->driver->context_dtor) | 
 | 					dev->driver->context_dtor(dev, | 
 | 								  pos->handle); | 
 |  | 
 | 				drm_ctxbitmap_free(dev, pos->handle); | 
 |  | 
 | 				list_del(&pos->head); | 
 | 				drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST); | 
 | 				--dev->ctx_count; | 
 | 			} | 
 | 		} | 
 | 	} | 
 | 	mutex_unlock(&dev->ctxlist_mutex); | 
 |  | 
 | 	mutex_lock(&dev->struct_mutex); | 
 | 	if (priv->remove_auth_on_close == 1) { | 
 | 		drm_file_t *temp = dev->file_first; | 
 | 		while (temp) { | 
 | 			temp->authenticated = 0; | 
 | 			temp = temp->next; | 
 | 		} | 
 | 	} | 
 | 	if (priv->prev) { | 
 | 		priv->prev->next = priv->next; | 
 | 	} else { | 
 | 		dev->file_first = priv->next; | 
 | 	} | 
 | 	if (priv->next) { | 
 | 		priv->next->prev = priv->prev; | 
 | 	} else { | 
 | 		dev->file_last = priv->prev; | 
 | 	} | 
 | 	mutex_unlock(&dev->struct_mutex); | 
 |  | 
 | 	if (dev->driver->postclose) | 
 | 		dev->driver->postclose(dev, priv); | 
 | 	drm_free(priv, sizeof(*priv), DRM_MEM_FILES); | 
 |  | 
 | 	/* ======================================================== | 
 | 	 * End inline drm_release | 
 | 	 */ | 
 |  | 
 | 	atomic_inc(&dev->counts[_DRM_STAT_CLOSES]); | 
 | 	spin_lock(&dev->count_lock); | 
 | 	if (!--dev->open_count) { | 
 | 		if (atomic_read(&dev->ioctl_count) || dev->blocked) { | 
 | 			DRM_ERROR("Device busy: %d %d\n", | 
 | 				  atomic_read(&dev->ioctl_count), dev->blocked); | 
 | 			spin_unlock(&dev->count_lock); | 
 | 			unlock_kernel(); | 
 | 			return -EBUSY; | 
 | 		} | 
 | 		spin_unlock(&dev->count_lock); | 
 | 		unlock_kernel(); | 
 | 		return drm_lastclose(dev); | 
 | 	} | 
 | 	spin_unlock(&dev->count_lock); | 
 |  | 
 | 	unlock_kernel(); | 
 |  | 
 | 	return retcode; | 
 | } | 
 | EXPORT_SYMBOL(drm_release); | 
 |  | 
 | /** No-op. */ | 
 | unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait) | 
 | { | 
 | 	return 0; | 
 | } | 
 | EXPORT_SYMBOL(drm_poll); |