- 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 "drmP.h"
#include <linux/poll.h>
#include <linux/slab.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);
/* 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);