kernel-ark/drivers/char/drm/drm_fops.c
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

452 lines
12 KiB
C

/**
* \file drm_fops.h
* 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>
static int drm_setup( drm_device_t *dev )
{
int i;
int ret;
if (dev->driver->presetup)
{
ret=dev->driver->presetup(dev);
if (ret!=0)
return ret;
}
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 < DRM_ARRAY_SIZE(dev->counts) ; i++ )
atomic_set( &dev->counts[i], 0 );
for ( i = 0 ; i < DRM_HASH_SIZE ; i++ ) {
dev->magiclist[i].head = NULL;
dev->magiclist[i].tail = NULL;
}
dev->maplist = drm_alloc(sizeof(*dev->maplist),
DRM_MEM_MAPS);
if(dev->maplist == NULL) return -ENOMEM;
memset(dev->maplist, 0, sizeof(*dev->maplist));
INIT_LIST_HEAD(&dev->maplist->head);
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_rp = dev->buf;
dev->buf_wp = dev->buf;
dev->buf_end = dev->buf + DRM_BSZ;
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.
*/
if (dev->driver->postsetup)
dev->driver->postsetup(dev);
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);
/**
* 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 takedown().
*/
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->prerelease)
dev->driver->prerelease(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->release)
dev->driver->release(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->release && 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 ) {
if (dev->driver->release)
dev->driver->release(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(dev, filp);
}
drm_fasync( -1, filp, 0 );
down( &dev->ctxlist_sem );
if ( !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;
}
}
}
up( &dev->ctxlist_sem );
down( &dev->struct_sem );
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;
}
up( &dev->struct_sem );
if (dev->driver->free_filp_priv)
dev->driver->free_filp_priv(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_takedown( dev );
}
spin_unlock( &dev->count_lock );
unlock_kernel();
return retcode;
}
EXPORT_SYMBOL(drm_release);
/**
* 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.
*/
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;
priv->authenticated = capable(CAP_SYS_ADMIN);
priv->lock_count = 0;
if (dev->driver->open_helper) {
ret=dev->driver->open_helper(dev, priv);
if (ret < 0)
goto out_free;
}
down(&dev->struct_sem);
if (!dev->file_last) {
priv->next = NULL;
priv->prev = NULL;
dev->file_first = priv;
dev->file_last = priv;
} else {
priv->next = NULL;
priv->prev = dev->file_last;
dev->file_last->next = priv;
dev->file_last = priv;
}
up(&dev->struct_sem);
#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_flush(struct file *filp)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->head->dev;
DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
current->pid, (long)old_encode_dev(priv->head->device), dev->open_count);
return 0;
}
EXPORT_SYMBOL(drm_flush);
/** 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);
/** No-op. */
unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
{
return 0;
}
EXPORT_SYMBOL(drm_poll);
/** No-op. */
ssize_t drm_read(struct file *filp, char __user *buf, size_t count, loff_t *off)
{
return 0;
}