--- /dev/null
+/*
+ * drivers/base/sw_sync.c
+ *
+ * Copyright (C) 2012 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/file.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/syscalls.h>
+#include <linux/uaccess.h>
+
+#include "sw_sync.h"
+
+static int sw_sync_cmp(u32 a, u32 b)
+{
+ if (a == b)
+ return 0;
+
+ return ((s32)a - (s32)b) < 0 ? -1 : 1;
+}
+
+struct sync_pt *sw_sync_pt_create(struct sw_sync_timeline *obj, u32 value)
+{
+ struct sw_sync_pt *pt;
+
+ pt = (struct sw_sync_pt *)
+ sync_pt_create(&obj->obj, sizeof(struct sw_sync_pt));
+
+ pt->value = value;
+
+ return (struct sync_pt *)pt;
+}
+EXPORT_SYMBOL(sw_sync_pt_create);
+
+static struct sync_pt *sw_sync_pt_dup(struct sync_pt *sync_pt)
+{
+ struct sw_sync_pt *pt = (struct sw_sync_pt *)sync_pt;
+ struct sw_sync_timeline *obj =
+ (struct sw_sync_timeline *)sync_pt_parent(sync_pt);
+
+ return (struct sync_pt *)sw_sync_pt_create(obj, pt->value);
+}
+
+static int sw_sync_pt_has_signaled(struct sync_pt *sync_pt)
+{
+ struct sw_sync_pt *pt = (struct sw_sync_pt *)sync_pt;
+ struct sw_sync_timeline *obj =
+ (struct sw_sync_timeline *)sync_pt_parent(sync_pt);
+
+ return sw_sync_cmp(obj->value, pt->value) >= 0;
+}
+
+static int sw_sync_pt_compare(struct sync_pt *a, struct sync_pt *b)
+{
+ struct sw_sync_pt *pt_a = (struct sw_sync_pt *)a;
+ struct sw_sync_pt *pt_b = (struct sw_sync_pt *)b;
+
+ return sw_sync_cmp(pt_a->value, pt_b->value);
+}
+
+static int sw_sync_fill_driver_data(struct sync_pt *sync_pt,
+ void *data, int size)
+{
+ struct sw_sync_pt *pt = (struct sw_sync_pt *)sync_pt;
+
+ if (size < sizeof(pt->value))
+ return -ENOMEM;
+
+ memcpy(data, &pt->value, sizeof(pt->value));
+
+ return sizeof(pt->value);
+}
+
+static void sw_sync_timeline_value_str(struct sync_timeline *sync_timeline,
+ char *str, int size)
+{
+ struct sw_sync_timeline *timeline =
+ (struct sw_sync_timeline *)sync_timeline;
+ snprintf(str, size, "%d", timeline->value);
+}
+
+static void sw_sync_pt_value_str(struct sync_pt *sync_pt,
+ char *str, int size)
+{
+ struct sw_sync_pt *pt = (struct sw_sync_pt *)sync_pt;
+
+ snprintf(str, size, "%d", pt->value);
+}
+
+static struct sync_timeline_ops sw_sync_timeline_ops = {
+ .driver_name = "sw_sync",
+ .dup = sw_sync_pt_dup,
+ .has_signaled = sw_sync_pt_has_signaled,
+ .compare = sw_sync_pt_compare,
+ .fill_driver_data = sw_sync_fill_driver_data,
+ .timeline_value_str = sw_sync_timeline_value_str,
+ .pt_value_str = sw_sync_pt_value_str,
+};
+
+struct sw_sync_timeline *sw_sync_timeline_create(const char *name)
+{
+ struct sw_sync_timeline *obj = (struct sw_sync_timeline *)
+ sync_timeline_create(&sw_sync_timeline_ops,
+ sizeof(struct sw_sync_timeline),
+ name);
+
+ return obj;
+}
+EXPORT_SYMBOL(sw_sync_timeline_create);
+
+void sw_sync_timeline_inc(struct sw_sync_timeline *obj, u32 inc)
+{
+ obj->value += inc;
+
+ sync_timeline_signal(&obj->obj);
+}
+EXPORT_SYMBOL(sw_sync_timeline_inc);
+
+#ifdef CONFIG_SW_SYNC_USER
+/* *WARNING*
+ *
+ * improper use of this can result in deadlocking kernel drivers from userspace.
+ */
+
+/* opening sw_sync create a new sync obj */
+static int sw_sync_open(struct inode *inode, struct file *file)
+{
+ struct sw_sync_timeline *obj;
+ char task_comm[TASK_COMM_LEN];
+
+ get_task_comm(task_comm, current);
+
+ obj = sw_sync_timeline_create(task_comm);
+ if (obj == NULL)
+ return -ENOMEM;
+
+ file->private_data = obj;
+
+ return 0;
+}
+
+static int sw_sync_release(struct inode *inode, struct file *file)
+{
+ struct sw_sync_timeline *obj = file->private_data;
+
+ sync_timeline_destroy(&obj->obj);
+ return 0;
+}
+
+static long sw_sync_ioctl_create_fence(struct sw_sync_timeline *obj,
+ unsigned long arg)
+{
+ int fd = get_unused_fd_flags(O_CLOEXEC);
+ int err;
+ struct sync_pt *pt;
+ struct sync_fence *fence;
+ struct sw_sync_create_fence_data data;
+
+ if (fd < 0)
+ return fd;
+
+ if (copy_from_user(&data, (void __user *)arg, sizeof(data))) {
+ err = -EFAULT;
+ goto err;
+ }
+
+ pt = sw_sync_pt_create(obj, data.value);
+ if (pt == NULL) {
+ err = -ENOMEM;
+ goto err;
+ }
+
+ data.name[sizeof(data.name) - 1] = '\0';
+ fence = sync_fence_create(data.name, pt);
+ if (fence == NULL) {
+ sync_pt_free(pt);
+ err = -ENOMEM;
+ goto err;
+ }
+
+ data.fence = fd;
+ if (copy_to_user((void __user *)arg, &data, sizeof(data))) {
+ sync_fence_put(fence);
+ err = -EFAULT;
+ goto err;
+ }
+
+ sync_fence_install(fence, fd);
+
+ return 0;
+
+err:
+ put_unused_fd(fd);
+ return err;
+}
+
+static long sw_sync_ioctl_inc(struct sw_sync_timeline *obj, unsigned long arg)
+{
+ u32 value;
+
+ if (copy_from_user(&value, (void __user *)arg, sizeof(value)))
+ return -EFAULT;
+
+ sw_sync_timeline_inc(obj, value);
+
+ return 0;
+}
+
+static long sw_sync_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct sw_sync_timeline *obj = file->private_data;
+
+ switch (cmd) {
+ case SW_SYNC_IOC_CREATE_FENCE:
+ return sw_sync_ioctl_create_fence(obj, arg);
+
+ case SW_SYNC_IOC_INC:
+ return sw_sync_ioctl_inc(obj, arg);
+
+ default:
+ return -ENOTTY;
+ }
+}
+
+static const struct file_operations sw_sync_fops = {
+ .owner = THIS_MODULE,
+ .open = sw_sync_open,
+ .release = sw_sync_release,
+ .unlocked_ioctl = sw_sync_ioctl,
+ .compat_ioctl = sw_sync_ioctl,
+};
+
+static struct miscdevice sw_sync_dev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "sw_sync",
+ .fops = &sw_sync_fops,
+};
+
+static int __init sw_sync_device_init(void)
+{
+ return misc_register(&sw_sync_dev);
+}
+
+static void __exit sw_sync_device_remove(void)
+{
+ misc_deregister(&sw_sync_dev);
+}
+
+module_init(sw_sync_device_init);
+module_exit(sw_sync_device_remove);
+
+#endif /* CONFIG_SW_SYNC_USER */
Code Review / kvmfornfv.git / blobdiff