/** * \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 <linux/poll.h> #include <linux/slab.h> #include <linux/module.h> /* from BKL pushdown: note that nothing else serializes idr_find() */ DEFINE_MUTEX(drm_global_mutex); EXPORT_SYMBOL(drm_global_mutex); static int drm_open_helper(struct inode *inode, struct file *filp, struct drm_device * dev); static int drm_setup(struct drm_device * dev) { int i; int ret; if (dev->driver->firstopen) { ret = dev->driver->firstopen(dev); if (ret != 0) return ret; } atomic_set(&dev->ioctl_count, 0); atomic_set(&dev->vma_count, 0); if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) && !drm_core_check_feature(dev, DRIVER_MODESET)) { dev->buf_use = 0; atomic_set(&dev->buf_alloc, 0); 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); dev->sigdata.lock = NULL; dev->queue_count = 0; dev->queue_reserved = 0; dev->queue_slots = 0; dev->queuelist = NULL; 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) { struct drm_device *dev = NULL; int minor_id = iminor(inode); struct drm_minor *minor; int retcode = 0; minor = idr_find(&drm_minors_idr, minor_id); if (!minor) return -ENODEV; if (!(dev = minor->dev)) return -ENODEV; retcode = drm_open_helper(inode, filp, dev); if (!retcode) { atomic_inc(&dev->counts[_DRM_STAT_OPENS]); if (!dev->open_count++) retcode = drm_setup(dev); } if (!retcode) { mutex_lock(&dev->struct_mutex); if (minor->type == DRM_MINOR_LEGACY) { if (dev->dev_mapping == NULL) dev->dev_mapping = inode->i_mapping; else if (dev->dev_mapping != inode->i_mapping) retcode = -ENODEV; } mutex_unlock(&dev->struct_mutex); } 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) { struct drm_device *dev = NULL; struct drm_minor *minor; int minor_id = iminor(inode); int err = -ENODEV; const struct file_operations *old_fops; DRM_DEBUG("\n"); mutex_lock(&drm_global_mutex); minor = idr_find(&drm_minors_idr, minor_id); if (!minor) goto out; if (!(dev = minor->dev)) goto out; old_fops = filp->f_op; filp->f_op = fops_get(dev->driver->fops); if (filp->f_op == NULL) { filp->f_op = old_fops; goto out; } 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); out: mutex_unlock(&drm_global_mutex); 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, struct drm_device * dev) { int minor_id = iminor(inode); struct drm_file *priv; int ret; if (filp->f_flags & O_EXCL) return -EBUSY; /* No exclusive opens */ if (!drm_cpu_valid()) return -EINVAL; if (dev->switch_power_state != DRM_SWITCH_POWER_ON) return -EINVAL; DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor_id); priv = kzalloc(sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; filp->private_data = priv; priv->filp = filp; priv->uid = current_euid(); priv->pid = task_pid_nr(current); priv->minor = idr_find(&drm_minors_idr, minor_id); priv->ioctl_count = 0; /* for compatibility root is always authenticated */ priv->authenticated = capable(CAP_SYS_ADMIN); priv->lock_count = 0; INIT_LIST_HEAD(&priv->lhead); INIT_LIST_HEAD(&priv->fbs); INIT_LIST_HEAD(&priv->event_list); init_waitqueue_head(&priv->event_wait); priv->event_space = 4096; /* set aside 4k for event buffer */ if (dev->driver->driver_features & DRIVER_GEM) drm_gem_open(dev, priv); if (dev->driver->open) { ret = dev->driver->open(dev, priv); if (ret < 0) goto out_free; } /* if there is no current master make this fd it */ mutex_lock(&dev->struct_mutex); if (!priv->minor->master) { /* create a new master */ priv->minor->master = drm_master_create(priv->minor); if (!priv->minor->master) { mutex_unlock(&dev->struct_mutex); ret = -ENOMEM; goto out_free; } priv->is_master = 1; /* take another reference for the copy in the local file priv */ priv->master = drm_master_get(priv->minor->master); priv->authenticated = 1; mutex_unlock(&dev->struct_mutex); if (dev->driver->master_create) { ret = dev->driver->master_create(dev, priv->master); if (ret) { mutex_lock(&dev->struct_mutex); /* drop both references if this fails */ drm_master_put(&priv->minor->master); drm_master_put(&priv->master); mutex_unlock(&dev->struct_mutex); goto out_free; } } mutex_lock(&dev->struct_mutex); if (dev->driver->master_set) { ret = dev->driver->master_set(dev, priv, true); if (ret) { /* drop both references if this fails */ drm_master_put(&priv->minor->master); drm_master_put(&priv->master); mutex_unlock(&dev->struct_mutex); goto out_free; } } mutex_unlock(&dev->struct_mutex); } else { /* get a reference to the master */ priv->master = drm_master_get(priv->minor->master); mutex_unlock(&dev->struct_mutex); } mutex_lock(&dev->struct_mutex); list_add(&priv->lhead, &dev->filelist); 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: kfree(priv); filp->private_data = NULL; return ret; } /** No-op. */ int drm_fasync(int fd, struct file *filp, int on) { struct drm_file *priv = filp->private_data; struct drm_device *dev = priv->minor->dev; DRM_DEBUG("fd = %d, device = 0x%lx\n", fd, (long)old_encode_dev(priv->minor->device)); return fasync_helper(fd, filp, on, &dev->buf_async); } EXPORT_SYMBOL(drm_fasync); /* * Reclaim locked buffers; note that this may be a bad idea if the current * context doesn't have the hw lock... */ static void drm_reclaim_locked_buffers(struct drm_device *dev, struct file *f) { struct drm_file *file_priv = f->private_data; if (drm_i_have_hw_lock(dev, file_priv)) { dev->driver->reclaim_buffers_locked(dev, file_priv); } else { unsigned long _end = jiffies + 3 * DRM_HZ; int locked = 0; drm_idlelock_take(&file_priv->master->lock); /* * Wait for a while. */ do { spin_lock_bh(&file_priv->master->lock.spinlock); locked = file_priv->master->lock.idle_has_lock; spin_unlock_bh(&file_priv->master->lock.spinlock); if (locked) break; schedule(); } while (!time_after_eq(jiffies, _end)); if (!locked) { DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n" "\tdriver to use reclaim_buffers_idlelocked() instead.\n" "\tI will go on reclaiming the buffers anyway.\n"); } dev->driver->reclaim_buffers_locked(dev, file_priv); drm_idlelock_release(&file_priv->master->lock); } } static void drm_master_release(struct drm_device *dev, struct file *filp) { struct drm_file *file_priv = filp->private_data; if (dev->driver->reclaim_buffers_locked && file_priv->master->lock.hw_lock) drm_reclaim_locked_buffers(dev, filp); if (dev->driver->reclaim_buffers_idlelocked && file_priv->master->lock.hw_lock) { drm_idlelock_take(&file_priv->master->lock); dev->driver->reclaim_buffers_idlelocked(dev, file_priv); drm_idlelock_release(&file_priv->master->lock); } if (drm_i_have_hw_lock(dev, file_priv)) { DRM_DEBUG("File %p released, freeing lock for context %d\n", filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); drm_lock_free(&file_priv->master->lock, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); } if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) && !dev->driver->reclaim_buffers_locked) { dev->driver->reclaim_buffers(dev, file_priv); } } static void drm_events_release(struct drm_file *file_priv) { struct drm_device *dev = file_priv->minor->dev; struct drm_pending_event *e, *et; struct drm_pending_vblank_event *v, *vt; unsigned long flags; spin_lock_irqsave(&dev->event_lock, flags); /* Remove pending flips */ list_for_each_entry_safe(v, vt, &dev->vblank_event_list, base.link) if (v->base.file_priv == file_priv) { list_del(&v->base.link); drm_vblank_put(dev, v->pipe); v->base.destroy(&v->base); } /* Remove unconsumed events */ list_for_each_entry_safe(e, et, &file_priv->event_list, link) e->destroy(e); spin_unlock_irqrestore(&dev->event_lock, flags); } /** * Release file. * * \param inode device inode * \param file_priv DRM file private. * \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) { struct drm_file *file_priv = filp->private_data; struct drm_device *dev = file_priv->minor->dev; int retcode = 0; mutex_lock(&drm_global_mutex); DRM_DEBUG("open_count = %d\n", dev->open_count); if (dev->driver->preclose) dev->driver->preclose(dev, file_priv); /* ======================================================== * Begin inline drm_release */ DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n", task_pid_nr(current), (long)old_encode_dev(file_priv->minor->device), dev->open_count); /* Release any auth tokens that might point to this file_priv, (do that under the drm_global_mutex) */ if (file_priv->magic) (void) drm_remove_magic(file_priv->master, file_priv->magic); /* if the master has gone away we can't do anything with the lock */ if (file_priv->minor->master) drm_master_release(dev, filp); drm_events_release(file_priv); if (dev->driver->driver_features & DRIVER_GEM) drm_gem_release(dev, file_priv); if (dev->driver->driver_features & DRIVER_MODESET) drm_fb_release(file_priv); 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->tag == file_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); kfree(pos); --dev->ctx_count; } } } mutex_unlock(&dev->ctxlist_mutex); mutex_lock(&dev->struct_mutex); if (file_priv->is_master) { struct drm_master *master = file_priv->master; struct drm_file *temp; list_for_each_entry(temp, &dev->filelist, lhead) { if ((temp->master == file_priv->master) && (temp != file_priv)) temp->authenticated = 0; } /** * Since the master is disappearing, so is the * possibility to lock. */ if (master->lock.hw_lock) { if (dev->sigdata.lock == master->lock.hw_lock) dev->sigdata.lock = NULL; master->lock.hw_lock = NULL; master->lock.file_priv = NULL; wake_up_interruptible_all(&master->lock.lock_queue); } if (file_priv->minor->master == file_priv->master) { /* drop the reference held my the minor */ if (dev->driver->master_drop) dev->driver->master_drop(dev, file_priv, true); drm_master_put(&file_priv->minor->master); } } /* drop the reference held my the file priv */ drm_master_put(&file_priv->master); file_priv->is_master = 0; list_del(&file_priv->lhead); mutex_unlock(&dev->struct_mutex); if (dev->driver->postclose) dev->driver->postclose(dev, file_priv); kfree(file_priv); /* ======================================================== * End inline drm_release */ atomic_inc(&dev->counts[_DRM_STAT_CLOSES]); if (!--dev->open_count) { if (atomic_read(&dev->ioctl_count)) { DRM_ERROR("Device busy: %d\n", atomic_read(&dev->ioctl_count)); retcode = -EBUSY; } else retcode = drm_lastclose(dev); } mutex_unlock(&drm_global_mutex); return retcode; } EXPORT_SYMBOL(drm_release); static bool drm_dequeue_event(struct drm_file *file_priv, size_t total, size_t max, struct drm_pending_event **out) { struct drm_device *dev = file_priv->minor->dev; struct drm_pending_event *e; unsigned long flags; bool ret = false; spin_lock_irqsave(&dev->event_lock, flags); *out = NULL; if (list_empty(&file_priv->event_list)) goto out; e = list_first_entry(&file_priv->event_list, struct drm_pending_event, link); if (e->event->length + total > max) goto out; file_priv->event_space += e->event->length; list_del(&e->link); *out = e; ret = true; out: spin_unlock_irqrestore(&dev->event_lock, flags); return ret; } ssize_t drm_read(struct file *filp, char __user *buffer, size_t count, loff_t *offset) { struct drm_file *file_priv = filp->private_data; struct drm_pending_event *e; size_t total; ssize_t ret; ret = wait_event_interruptible(file_priv->event_wait, !list_empty(&file_priv->event_list)); if (ret < 0) return ret; total = 0; while (drm_dequeue_event(file_priv, total, count, &e)) { if (copy_to_user(buffer + total, e->event, e->event->length)) { total = -EFAULT; break; } total += e->event->length; e->destroy(e); } return total; } EXPORT_SYMBOL(drm_read); unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait) { struct drm_file *file_priv = filp->private_data; unsigned int mask = 0; poll_wait(filp, &file_priv->event_wait, wait); if (!list_empty(&file_priv->event_list)) mask |= POLLIN | POLLRDNORM; return mask; } EXPORT_SYMBOL(drm_poll);