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-rw-r--r--linux/fops.c218
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diff --git a/linux/fops.c b/linux/fops.c
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+++ b/linux/fops.c
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+/* fops.c -- File operations for DRM -*- linux-c -*-
+ * Created: Mon Jan 4 08:58:31 1999 by faith@precisioninsight.com
+ * Revised: Tue Oct 12 08:48:59 1999 by faith@precisioninsight.com
+ *
+ * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
+ * 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
+ * PRECISION INSIGHT 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.
+ *
+ * $PI: xc/programs/Xserver/hw/xfree86/os-support/linux/drm/kernel/fops.c,v 1.3 1999/08/20 15:36:45 faith Exp $
+ * $XFree86: xc/programs/Xserver/hw/xfree86/os-support/linux/drm/kernel/fops.c,v 1.1 1999/09/25 14:37:59 dawes Exp $
+ *
+ */
+
+#define __NO_VERSION__
+#include "drmP.h"
+
+/* drm_open is called whenever a process opens /dev/drm. */
+
+int drm_open_helper(struct inode *inode, struct file *filp, drm_device_t *dev)
+{
+ kdev_t minor = MINOR(inode->i_rdev);
+ drm_file_t *priv;
+
+ if (filp->f_flags & O_EXCL) return -EBUSY; /* No exclusive opens */
+
+ DRM_DEBUG("pid = %d, minor = %d\n", current->pid, minor);
+
+ priv = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
+ memset(priv, 0, sizeof(*priv));
+ filp->private_data = priv;
+ priv->uid = current->euid;
+ priv->pid = current->pid;
+ priv->minor = minor;
+ priv->dev = dev;
+ priv->ioctl_count = 0;
+ priv->authenticated = capable(CAP_SYS_ADMIN);
+
+ 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);
+
+ return 0;
+}
+
+int drm_flush(struct file *filp)
+{
+ drm_file_t *priv = filp->private_data;
+ drm_device_t *dev = priv->dev;
+
+ DRM_DEBUG("pid = %d, device = 0x%x, open_count = %d, f_count = %d\n",
+ current->pid, dev->device, dev->open_count, filp->f_count);
+ return 0;
+}
+
+/* drm_release is called whenever a process closes /dev/drm*. Linux calls
+ this only if any mappings have been closed. */
+
+int drm_release(struct inode *inode, struct file *filp)
+{
+ drm_file_t *priv = filp->private_data;
+ drm_device_t *dev = priv->dev;
+
+ DRM_DEBUG("pid = %d, device = 0x%x, open_count = %d\n",
+ current->pid, dev->device, dev->open_count);
+
+ if (_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock)
+ && dev->lock.pid == current->pid) {
+ DRM_ERROR("Process %d dead, freeing lock for context %d\n",
+ current->pid,
+ _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
+ 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. */
+ }
+ drm_reclaim_buffers(dev, priv->pid);
+
+ drm_fasync(-1, filp, 0);
+
+ down(&dev->struct_sem);
+ 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);
+
+ drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
+
+ return 0;
+}
+
+int drm_fasync(int fd, struct file *filp, int on)
+{
+ drm_file_t *priv = filp->private_data;
+ drm_device_t *dev = priv->dev;
+ int retcode;
+
+ DRM_DEBUG("fd = %d, device = 0x%x\n", fd, dev->device);
+ retcode = fasync_helper(fd, filp, on, &dev->buf_async);
+ if (retcode < 0) return retcode;
+ return 0;
+}
+
+
+/* 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 drm_read(struct file *filp, char *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);
+ }
+ copy_to_user_ret(buf, dev->buf_rp, cur, -EINVAL);
+ 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);;
+}
+
+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);
+ DRM_DEBUG("waking\n");
+ wake_up_interruptible(&dev->buf_readers);
+ return 0;
+}
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