- 根目录:
- drivers
- gpu
- drm
- drm_fops.c
/**
* \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 <drm/drmP.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/module.h>
#include "drm_legacy.h"
#include "drm_internal.h"
/* from BKL pushdown */
DEFINE_MUTEX(drm_global_mutex);
static int drm_open_helper(struct file *filp, struct drm_minor *minor);
static int drm_setup(struct drm_device * dev)
{
int ret;
if (dev->driver->firstopen &&
!drm_core_check_feature(dev, DRIVER_MODESET)) {
ret = dev->driver->firstopen(dev);
if (ret != 0)
return ret;
}
ret = drm_legacy_dma_setup(dev);
if (ret < 0)
return ret;
DRM_DEBUG("\n");
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;
struct drm_minor *minor;
int retcode;
int need_setup = 0;
minor = drm_minor_acquire(iminor(inode));
if (IS_ERR(minor))
return PTR_ERR(minor);
dev = minor->dev;
if (!dev->open_count++)
need_setup = 1;
/* share address_space across all char-devs of a single device */
filp->f_mapping = dev->anon_inode->i_mapping;
retcode = drm_open_helper(filp, minor);
if (retcode)
goto err_undo;
if (need_setup) {
retcode = drm_setup(dev);
if (retcode)
goto err_undo;
}
return 0;
err_undo:
dev->open_count--;
drm_minor_release(minor);
return retcode;
}
EXPORT_SYMBOL(drm_open);
/**
* 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(__sparc__) && !defined(__sparc_v9__)
return 0; /* No cmpxchg before v9 sparc. */
#endif
return 1;
}
/**
* drm_new_set_master - Allocate a new master object and become master for the
* associated master realm.
*
* @dev: The associated device.
* @fpriv: File private identifying the client.
*
* This function must be called with dev::struct_mutex held.
* Returns negative error code on failure. Zero on success.
*/
int drm_new_set_master(struct drm_device *dev, struct drm_file *fpriv)
{
struct drm_master *old_master;
int ret;
lockdep_assert_held_once(&dev->master_mutex);
/* create a new master */
fpriv->minor->master = drm_master_create(fpriv->minor);
if (!fpriv->minor->master)
return -ENOMEM;
/* take another reference for the copy in the local file priv */
old_master = fpriv->master;
fpriv->master = drm_master_get(fpriv->minor->master);
if (dev->driver->master_create) {
ret = dev->driver->master_create(dev, fpriv->master);
if (ret)
goto out_err;
}
if (dev->driver->master_set) {
ret = dev->driver->master_set(dev, fpriv, true);
if (ret)
goto out_err;
}
fpriv->is_master = 1;
fpriv->allowed_master = 1;
fpriv->authenticated = 1;
if (old_master)
drm_master_put(&old_master);
return 0;
out_err:
/* drop both references and restore old master on failure */
drm_master_put(&fpriv->minor->master);
drm_master_put(&fpriv->master);
fpriv->master = old_master;
return ret;
}
/**
* Called whenever a process opens /dev/drm.
*
* \param filp file pointer.
* \param minor acquired minor-object.
* \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 file *filp, struct drm_minor *minor)
{
struct drm_device *dev = minor->dev;
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 && dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF)
return -EINVAL;
DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor->index);
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
filp->private_data = priv;
priv->filp = filp;
priv->uid = current_euid();
priv->pid = get_pid(task_pid(current));
priv->minor = minor;
/* 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);
mutex_init(&priv->fbs_lock);
INIT_LIST_HEAD(&priv->blobs);
INIT_LIST_HEAD(&priv->event_list);
init_waitqueue_head(&priv->event_wait);
priv->event_space = 4096; /* set aside 4k for event buffer */
if (drm_core_check_feature(dev, DRIVER_GEM))
drm_gem_open(dev, priv);
if (drm_core_check_feature(dev, DRIVER_PRIME))
drm_prime_init_file_private(&priv->prime);
if (dev->driver->open) {
ret = dev->driver->open(dev, priv);
if (ret < 0)
goto out_prime_destroy;
}
/* if there is no current master make this fd it, but do not create
* any master object for render clients */
mutex_lock(&dev->master_mutex);
if (drm_is_primary_client(priv) && !priv->minor->master) {
/* create a new master */
ret = drm_new_set_master(dev, priv);
if (ret)
goto out_close;
} else if (drm_is_primary_client(priv)) {
/* get a reference to the master */
priv->master = drm_master_get(priv->minor->master);
}
mutex_unlock(&dev->master_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 = list_entry(pci_root_buses.next,
struct pci_bus, node);
if (b)
dev->hose = b->sysdata;
}
}
#endif
return 0;
out_close:
mutex_unlock(&dev->master_mutex);
if (dev->driver->postclose)
dev->driver->postclose(dev, priv);
out_prime_destroy:
if (drm_core_check_feature(dev, DRIVER_PRIME))
drm_prime_destroy_file_private(&priv->prime);
if (drm_core_check_feature(dev, DRIVER_GEM))
drm_gem_release(dev, priv);
put_pid(priv->pid);
kfree(priv);
filp->private_data = NULL;
return ret;
}
static void drm_master_release(struct drm_device *dev, struct file *filp)
{
struct drm_file *file_priv = filp->private_data;
if (drm_legacy_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_legacy_lock_free(&file_priv->master->lock,
_DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
}
}
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) {
list_del(&e->link);
e->destroy(e);
}
spin_unlock_irqrestore(&dev->event_lock, flags);
}
/**
* drm_legacy_dev_reinit
*
* Reinitializes a legacy/ums drm device in it's lastclose function.
*/
static void drm_legacy_dev_reinit(struct drm_device *dev)
{
if (drm_core_check_feature(dev, DRIVER_MODESET))
return;
dev->sigdata.lock = NULL;
dev->context_flag = 0;
dev->last_context = 0;
dev->if_version = 0;
}
/**
* Take down the DRM device.
*
* \param dev DRM device structure.
*
* Frees every resource in \p dev.
*
* \sa drm_device
*/
int drm_lastclose(struct drm_device * dev)
{
DRM_DEBUG("\n");
if (dev->driver->lastclose)
dev->driver->lastclose(dev);
DRM_DEBUG("driver lastclose completed\n");
if (dev->irq_enabled && !drm_core_check_feature(dev, DRIVER_MODESET))
drm_irq_uninstall(dev);
mutex_lock(&dev->struct_mutex);
drm_agp_clear(dev);
drm_legacy_sg_cleanup(dev);
drm_legacy_vma_flush(dev);
drm_legacy_dma_takedown(dev);
mutex_unlock(&dev->struct_mutex);
drm_legacy_dev_reinit(dev);
DRM_DEBUG("lastclose completed\n");
return 0;
}
/**
* 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_minor *minor = file_priv->minor;
struct drm_device *dev = minor->dev;
int retcode = 0;
mutex_lock(&drm_global_mutex);
DRM_DEBUG("open_count = %d\n", dev->open_count);
mutex_lock(&dev->struct_mutex);
list_del(&file_priv->lhead);
if (file_priv->magic)
idr_remove(&file_priv->master->magic_map, file_priv->magic);
mutex_unlock(&dev->struct_mutex);
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->kdev->devt),
dev->open_count);
/* if the master has gone away we can't do anything with the lock */
if (file_priv->minor->master)
drm_master_release(dev, filp);
if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
drm_legacy_reclaim_buffers(dev, file_priv);
drm_events_release(file_priv);
if (drm_core_check_feature(dev, DRIVER_MODESET)) {
drm_fb_release(file_priv);
drm_property_destroy_user_blobs(dev, file_priv);
}
if (drm_core_check_feature(dev, DRIVER_GEM))
drm_gem_release(dev, file_priv);
drm_legacy_ctxbitmap_flush(dev, file_priv);
mutex_lock(&dev->master_mutex);
if (file_priv->is_master) {
struct drm_master *master = file_priv->master;
/**
* Since the master is disappearing, so is the
* possibility to lock.
*/
mutex_lock(&dev->struct_mutex);
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);
}
mutex_unlock(&dev->struct_mutex);
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 master reference held by the file priv */
if (file_priv->master)
drm_master_put(&file_priv->master);
file_priv->is_master = 0;
mutex_unlock(&dev->master_mutex);
if (dev->driver->postclose)
dev->driver->postclose(dev, file_priv);
if (drm_core_check_feature(dev, DRIVER_PRIME))
drm_prime_destroy_file_private(&file_priv->prime);
WARN_ON(!list_empty(&file_priv->event_list));
put_pid(file_priv->pid);
kfree(file_priv);
/* ========================================================
* End inline drm_release
*/
if (!--dev->open_count) {
retcode = drm_lastclose(dev);
if (drm_device_is_unplugged(dev))
drm_put_dev(dev);
}
mutex_unlock(&drm_global_mutex);
drm_minor_release(minor);
return retcode;
}
EXPORT_SYMBOL(drm_release);
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_device *dev = file_priv->minor->dev;
ssize_t ret = 0;
if (!access_ok(VERIFY_WRITE, buffer, count))
return -EFAULT;
spin_lock_irq(&dev->event_lock);
for (;;) {
if (list_empty(&file_priv->event_list)) {
if (ret)
break;
if (filp->f_flags & O_NONBLOCK) {
ret = -EAGAIN;
break;
}
spin_unlock_irq(&dev->event_lock);
ret = wait_event_interruptible(file_priv->event_wait,
!list_empty(&file_priv->event_list));
spin_lock_irq(&dev->event_lock);
if (ret < 0)
break;
ret = 0;
} else {
struct drm_pending_event *e;
e = list_first_entry(&file_priv->event_list,
struct drm_pending_event, link);
if (e->event->length + ret > count)
break;
if (__copy_to_user_inatomic(buffer + ret,
e->event, e->event->length)) {
if (ret == 0)
ret = -EFAULT;
break;
}
file_priv->event_space += e->event->length;
ret += e->event->length;
list_del(&e->link);
e->destroy(e);
}
}
spin_unlock_irq(&dev->event_lock);
return ret;
}
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);