linux/drivers/char/drm/gamma_context.h
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

493 lines
13 KiB
C

/* drm_context.h -- IOCTLs for generic contexts -*- linux-c -*-
* Created: Fri Nov 24 18:31:37 2000 by gareth@valinux.com
*
* Copyright 1999, 2000 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.
*
* Authors:
* Rickard E. (Rik) Faith <faith@valinux.com>
* Gareth Hughes <gareth@valinux.com>
* ChangeLog:
* 2001-11-16 Torsten Duwe <duwe@caldera.de>
* added context constructor/destructor hooks,
* needed by SiS driver's memory management.
*/
/* ================================================================
* Old-style context support -- only used by gamma.
*/
/* The drm_read and drm_write_string code (especially that which manages
the circular buffer), is based on Alessandro Rubini's LINUX DEVICE
DRIVERS (Cambridge: O'Reilly, 1998), pages 111-113. */
ssize_t gamma_fops_read(struct file *filp, char __user *buf, size_t count, loff_t *off)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
int left;
int avail;
int send;
int cur;
DRM_DEBUG("%p, %p\n", dev->buf_rp, dev->buf_wp);
while (dev->buf_rp == dev->buf_wp) {
DRM_DEBUG(" sleeping\n");
if (filp->f_flags & O_NONBLOCK) {
return -EAGAIN;
}
interruptible_sleep_on(&dev->buf_readers);
if (signal_pending(current)) {
DRM_DEBUG(" interrupted\n");
return -ERESTARTSYS;
}
DRM_DEBUG(" awake\n");
}
left = (dev->buf_rp + DRM_BSZ - dev->buf_wp) % DRM_BSZ;
avail = DRM_BSZ - left;
send = DRM_MIN(avail, count);
while (send) {
if (dev->buf_wp > dev->buf_rp) {
cur = DRM_MIN(send, dev->buf_wp - dev->buf_rp);
} else {
cur = DRM_MIN(send, dev->buf_end - dev->buf_rp);
}
if (copy_to_user(buf, dev->buf_rp, cur))
return -EFAULT;
dev->buf_rp += cur;
if (dev->buf_rp == dev->buf_end) dev->buf_rp = dev->buf;
send -= cur;
}
wake_up_interruptible(&dev->buf_writers);
return DRM_MIN(avail, count);
}
/* In an incredibly convoluted setup, the kernel module actually calls
* back into the X server to perform context switches on behalf of the
* 3d clients.
*/
int DRM(write_string)(drm_device_t *dev, const char *s)
{
int left = (dev->buf_rp + DRM_BSZ - dev->buf_wp) % DRM_BSZ;
int send = strlen(s);
int count;
DRM_DEBUG("%d left, %d to send (%p, %p)\n",
left, send, dev->buf_rp, dev->buf_wp);
if (left == 1 || dev->buf_wp != dev->buf_rp) {
DRM_ERROR("Buffer not empty (%d left, wp = %p, rp = %p)\n",
left,
dev->buf_wp,
dev->buf_rp);
}
while (send) {
if (dev->buf_wp >= dev->buf_rp) {
count = DRM_MIN(send, dev->buf_end - dev->buf_wp);
if (count == left) --count; /* Leave a hole */
} else {
count = DRM_MIN(send, dev->buf_rp - dev->buf_wp - 1);
}
strncpy(dev->buf_wp, s, count);
dev->buf_wp += count;
if (dev->buf_wp == dev->buf_end) dev->buf_wp = dev->buf;
send -= count;
}
if (dev->buf_async) kill_fasync(&dev->buf_async, SIGIO, POLL_IN);
DRM_DEBUG("waking\n");
wake_up_interruptible(&dev->buf_readers);
return 0;
}
unsigned int gamma_fops_poll(struct file *filp, struct poll_table_struct *wait)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
poll_wait(filp, &dev->buf_readers, wait);
if (dev->buf_wp != dev->buf_rp) return POLLIN | POLLRDNORM;
return 0;
}
int DRM(context_switch)(drm_device_t *dev, int old, int new)
{
char buf[64];
drm_queue_t *q;
if (test_and_set_bit(0, &dev->context_flag)) {
DRM_ERROR("Reentering -- FIXME\n");
return -EBUSY;
}
DRM_DEBUG("Context switch from %d to %d\n", old, new);
if (new >= dev->queue_count) {
clear_bit(0, &dev->context_flag);
return -EINVAL;
}
if (new == dev->last_context) {
clear_bit(0, &dev->context_flag);
return 0;
}
q = dev->queuelist[new];
atomic_inc(&q->use_count);
if (atomic_read(&q->use_count) == 1) {
atomic_dec(&q->use_count);
clear_bit(0, &dev->context_flag);
return -EINVAL;
}
/* This causes the X server to wake up & do a bunch of hardware
* interaction to actually effect the context switch.
*/
sprintf(buf, "C %d %d\n", old, new);
DRM(write_string)(dev, buf);
atomic_dec(&q->use_count);
return 0;
}
int DRM(context_switch_complete)(drm_device_t *dev, int new)
{
drm_device_dma_t *dma = dev->dma;
dev->last_context = new; /* PRE/POST: This is the _only_ writer. */
dev->last_switch = jiffies;
if (!_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)) {
DRM_ERROR("Lock isn't held after context switch\n");
}
if (!dma || !(dma->next_buffer && dma->next_buffer->while_locked)) {
if (DRM(lock_free)(dev, &dev->lock.hw_lock->lock,
DRM_KERNEL_CONTEXT)) {
DRM_ERROR("Cannot free lock\n");
}
}
clear_bit(0, &dev->context_flag);
wake_up_interruptible(&dev->context_wait);
return 0;
}
static int DRM(init_queue)(drm_device_t *dev, drm_queue_t *q, drm_ctx_t *ctx)
{
DRM_DEBUG("\n");
if (atomic_read(&q->use_count) != 1
|| atomic_read(&q->finalization)
|| atomic_read(&q->block_count)) {
DRM_ERROR("New queue is already in use: u%d f%d b%d\n",
atomic_read(&q->use_count),
atomic_read(&q->finalization),
atomic_read(&q->block_count));
}
atomic_set(&q->finalization, 0);
atomic_set(&q->block_count, 0);
atomic_set(&q->block_read, 0);
atomic_set(&q->block_write, 0);
atomic_set(&q->total_queued, 0);
atomic_set(&q->total_flushed, 0);
atomic_set(&q->total_locks, 0);
init_waitqueue_head(&q->write_queue);
init_waitqueue_head(&q->read_queue);
init_waitqueue_head(&q->flush_queue);
q->flags = ctx->flags;
DRM(waitlist_create)(&q->waitlist, dev->dma->buf_count);
return 0;
}
/* drm_alloc_queue:
PRE: 1) dev->queuelist[0..dev->queue_count] is allocated and will not
disappear (so all deallocation must be done after IOCTLs are off)
2) dev->queue_count < dev->queue_slots
3) dev->queuelist[i].use_count == 0 and
dev->queuelist[i].finalization == 0 if i not in use
POST: 1) dev->queuelist[i].use_count == 1
2) dev->queue_count < dev->queue_slots */
static int DRM(alloc_queue)(drm_device_t *dev)
{
int i;
drm_queue_t *queue;
int oldslots;
int newslots;
/* Check for a free queue */
for (i = 0; i < dev->queue_count; i++) {
atomic_inc(&dev->queuelist[i]->use_count);
if (atomic_read(&dev->queuelist[i]->use_count) == 1
&& !atomic_read(&dev->queuelist[i]->finalization)) {
DRM_DEBUG("%d (free)\n", i);
return i;
}
atomic_dec(&dev->queuelist[i]->use_count);
}
/* Allocate a new queue */
down(&dev->struct_sem);
queue = DRM(alloc)(sizeof(*queue), DRM_MEM_QUEUES);
memset(queue, 0, sizeof(*queue));
atomic_set(&queue->use_count, 1);
++dev->queue_count;
if (dev->queue_count >= dev->queue_slots) {
oldslots = dev->queue_slots * sizeof(*dev->queuelist);
if (!dev->queue_slots) dev->queue_slots = 1;
dev->queue_slots *= 2;
newslots = dev->queue_slots * sizeof(*dev->queuelist);
dev->queuelist = DRM(realloc)(dev->queuelist,
oldslots,
newslots,
DRM_MEM_QUEUES);
if (!dev->queuelist) {
up(&dev->struct_sem);
DRM_DEBUG("out of memory\n");
return -ENOMEM;
}
}
dev->queuelist[dev->queue_count-1] = queue;
up(&dev->struct_sem);
DRM_DEBUG("%d (new)\n", dev->queue_count - 1);
return dev->queue_count - 1;
}
int DRM(resctx)(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
drm_ctx_res_t __user *argp = (void __user *)arg;
drm_ctx_res_t res;
drm_ctx_t ctx;
int i;
DRM_DEBUG("%d\n", DRM_RESERVED_CONTEXTS);
if (copy_from_user(&res, argp, sizeof(res)))
return -EFAULT;
if (res.count >= DRM_RESERVED_CONTEXTS) {
memset(&ctx, 0, sizeof(ctx));
for (i = 0; i < DRM_RESERVED_CONTEXTS; i++) {
ctx.handle = i;
if (copy_to_user(&res.contexts[i],
&i,
sizeof(i)))
return -EFAULT;
}
}
res.count = DRM_RESERVED_CONTEXTS;
if (copy_to_user(argp, &res, sizeof(res)))
return -EFAULT;
return 0;
}
int DRM(addctx)(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
drm_ctx_t ctx;
drm_ctx_t __user *argp = (void __user *)arg;
if (copy_from_user(&ctx, argp, sizeof(ctx)))
return -EFAULT;
if ((ctx.handle = DRM(alloc_queue)(dev)) == DRM_KERNEL_CONTEXT) {
/* Init kernel's context and get a new one. */
DRM(init_queue)(dev, dev->queuelist[ctx.handle], &ctx);
ctx.handle = DRM(alloc_queue)(dev);
}
DRM(init_queue)(dev, dev->queuelist[ctx.handle], &ctx);
DRM_DEBUG("%d\n", ctx.handle);
if (copy_to_user(argp, &ctx, sizeof(ctx)))
return -EFAULT;
return 0;
}
int DRM(modctx)(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
drm_ctx_t ctx;
drm_queue_t *q;
if (copy_from_user(&ctx, (drm_ctx_t __user *)arg, sizeof(ctx)))
return -EFAULT;
DRM_DEBUG("%d\n", ctx.handle);
if (ctx.handle < 0 || ctx.handle >= dev->queue_count) return -EINVAL;
q = dev->queuelist[ctx.handle];
atomic_inc(&q->use_count);
if (atomic_read(&q->use_count) == 1) {
/* No longer in use */
atomic_dec(&q->use_count);
return -EINVAL;
}
if (DRM_BUFCOUNT(&q->waitlist)) {
atomic_dec(&q->use_count);
return -EBUSY;
}
q->flags = ctx.flags;
atomic_dec(&q->use_count);
return 0;
}
int DRM(getctx)(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
drm_ctx_t __user *argp = (void __user *)arg;
drm_ctx_t ctx;
drm_queue_t *q;
if (copy_from_user(&ctx, argp, sizeof(ctx)))
return -EFAULT;
DRM_DEBUG("%d\n", ctx.handle);
if (ctx.handle >= dev->queue_count) return -EINVAL;
q = dev->queuelist[ctx.handle];
atomic_inc(&q->use_count);
if (atomic_read(&q->use_count) == 1) {
/* No longer in use */
atomic_dec(&q->use_count);
return -EINVAL;
}
ctx.flags = q->flags;
atomic_dec(&q->use_count);
if (copy_to_user(argp, &ctx, sizeof(ctx)))
return -EFAULT;
return 0;
}
int DRM(switchctx)(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
drm_ctx_t ctx;
if (copy_from_user(&ctx, (drm_ctx_t __user *)arg, sizeof(ctx)))
return -EFAULT;
DRM_DEBUG("%d\n", ctx.handle);
return DRM(context_switch)(dev, dev->last_context, ctx.handle);
}
int DRM(newctx)(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
drm_ctx_t ctx;
if (copy_from_user(&ctx, (drm_ctx_t __user *)arg, sizeof(ctx)))
return -EFAULT;
DRM_DEBUG("%d\n", ctx.handle);
DRM(context_switch_complete)(dev, ctx.handle);
return 0;
}
int DRM(rmctx)(struct inode *inode, struct file *filp,
unsigned int cmd, unsigned long arg)
{
drm_file_t *priv = filp->private_data;
drm_device_t *dev = priv->dev;
drm_ctx_t ctx;
drm_queue_t *q;
drm_buf_t *buf;
if (copy_from_user(&ctx, (drm_ctx_t __user *)arg, sizeof(ctx)))
return -EFAULT;
DRM_DEBUG("%d\n", ctx.handle);
if (ctx.handle >= dev->queue_count) return -EINVAL;
q = dev->queuelist[ctx.handle];
atomic_inc(&q->use_count);
if (atomic_read(&q->use_count) == 1) {
/* No longer in use */
atomic_dec(&q->use_count);
return -EINVAL;
}
atomic_inc(&q->finalization); /* Mark queue in finalization state */
atomic_sub(2, &q->use_count); /* Mark queue as unused (pending
finalization) */
while (test_and_set_bit(0, &dev->interrupt_flag)) {
schedule();
if (signal_pending(current)) {
clear_bit(0, &dev->interrupt_flag);
return -EINTR;
}
}
/* Remove queued buffers */
while ((buf = DRM(waitlist_get)(&q->waitlist))) {
DRM(free_buffer)(dev, buf);
}
clear_bit(0, &dev->interrupt_flag);
/* Wakeup blocked processes */
wake_up_interruptible(&q->read_queue);
wake_up_interruptible(&q->write_queue);
wake_up_interruptible(&q->flush_queue);
/* Finalization over. Queue is made
available when both use_count and
finalization become 0, which won't
happen until all the waiting processes
stop waiting. */
atomic_dec(&q->finalization);
return 0;
}