diff options
Diffstat (limited to 'drivers/staging/android/sw_sync.c')
-rw-r--r-- | drivers/staging/android/sw_sync.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/staging/android/sw_sync.c b/drivers/staging/android/sw_sync.c new file mode 100644 index 000000000000..90e3ee5c299b --- /dev/null +++ b/drivers/staging/android/sw_sync.c @@ -0,0 +1,136 @@ +/* + * drivers/dma-buf/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/file.h> +#include <linux/fs.h> +#include <linux/uaccess.h> +#include <linux/sync_file.h> + +#include "uapi/sw_sync.h" +#include "sync.h" + +/* + * *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_debugfs_open(struct inode *inode, struct file *file) +{ + struct sync_timeline *obj; + char task_comm[TASK_COMM_LEN]; + + get_task_comm(task_comm, current); + + obj = sync_timeline_create("sw_sync", task_comm); + if (!obj) + return -ENOMEM; + + file->private_data = obj; + + return 0; +} + +static int sw_sync_debugfs_release(struct inode *inode, struct file *file) +{ + struct sync_timeline *obj = file->private_data; + + sync_timeline_destroy(obj); + return 0; +} + +static long sw_sync_ioctl_create_fence(struct sync_timeline *obj, + unsigned long arg) +{ + int fd = get_unused_fd_flags(O_CLOEXEC); + int err; + struct sync_pt *pt; + struct sync_file *sync_file; + 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 = sync_pt_create(obj, sizeof(*pt), data.value); + if (!pt) { + err = -ENOMEM; + goto err; + } + + sync_file = sync_file_create(&pt->base); + if (!sync_file) { + fence_put(&pt->base); + err = -ENOMEM; + goto err; + } + + data.fence = fd; + if (copy_to_user((void __user *)arg, &data, sizeof(data))) { + fput(sync_file->file); + err = -EFAULT; + goto err; + } + + fd_install(fd, sync_file->file); + + return 0; + +err: + put_unused_fd(fd); + return err; +} + +static long sw_sync_ioctl_inc(struct sync_timeline *obj, unsigned long arg) +{ + u32 value; + + if (copy_from_user(&value, (void __user *)arg, sizeof(value))) + return -EFAULT; + + sync_timeline_signal(obj, value); + + return 0; +} + +static long sw_sync_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct 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; + } +} + +const struct file_operations sw_sync_debugfs_fops = { + .open = sw_sync_debugfs_open, + .release = sw_sync_debugfs_release, + .unlocked_ioctl = sw_sync_ioctl, + .compat_ioctl = sw_sync_ioctl, +}; |