![Jonathan Corbet](/assets/img/avatar_default.png)
Most fasync implementations do something like: return fasync_helper(...); But fasync_helper() will return a positive value at times - a feature used in at least one place. Thus, a number of other drivers do: err = fasync_helper(...); if (err < 0) return err; return 0; In the interests of consistency and more concise code, it makes sense to map positive return values onto zero where ->fasync() is called. Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
552 lines
14 KiB
C
552 lines
14 KiB
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/smp_lock.h>
|
|
|
|
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]);
|
|
spin_lock(&dev->count_lock);
|
|
if (!dev->open_count++) {
|
|
spin_unlock(&dev->count_lock);
|
|
retcode = drm_setup(dev);
|
|
goto out;
|
|
}
|
|
spin_unlock(&dev->count_lock);
|
|
}
|
|
out:
|
|
mutex_lock(&dev->struct_mutex);
|
|
if (minor->type == DRM_MINOR_LEGACY) {
|
|
BUG_ON((dev->dev_mapping != NULL) &&
|
|
(dev->dev_mapping != inode->i_mapping));
|
|
if (dev->dev_mapping == NULL)
|
|
dev->dev_mapping = inode->i_mapping;
|
|
}
|
|
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");
|
|
|
|
/* BKL pushdown: note that nothing else serializes idr_find() */
|
|
lock_kernel();
|
|
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:
|
|
unlock_kernel();
|
|
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;
|
|
|
|
DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor_id);
|
|
|
|
priv = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
|
|
if (!priv)
|
|
return -ENOMEM;
|
|
|
|
memset(priv, 0, sizeof(*priv));
|
|
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);
|
|
|
|
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) {
|
|
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;
|
|
}
|
|
}
|
|
} 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:
|
|
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)
|
|
{
|
|
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);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* 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;
|
|
|
|
lock_kernel();
|
|
|
|
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);
|
|
|
|
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);
|
|
drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
|
|
--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 */
|
|
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);
|
|
drm_free(file_priv, sizeof(*file_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)) {
|
|
DRM_ERROR("Device busy: %d\n",
|
|
atomic_read(&dev->ioctl_count));
|
|
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);
|