/*-
- * * GPL LICENSE SUMMARY
- * *
- * * Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- * *
- * * This program is free software; you can redistribute it and/or modify
- * * it under the terms of version 2 of the GNU General Public License as
- * * published by the Free Software Foundation.
- * *
- * * 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.
- * *
- * * You should have received a copy of the GNU General Public License
- * * along with this program; if not, write to the Free Software
- * * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
- * * The full GNU General Public License is included in this distribution
- * * in the file called LICENSE.GPL.
- * *
- * * Contact Information:
- * * Intel Corporation
- * */
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ * The full GNU General Public License is included in this distribution
+ * in the file called LICENSE.GPL.
+ *
+ * Contact Information:
+ * Intel Corporation
+ */
#include <linux/eventfd.h>
#include <linux/miscdevice.h>
* get_files_struct is copied from fs/file.c
*/
struct files_struct *
-get_files_struct (struct task_struct *task)
+get_files_struct(struct task_struct *task)
{
struct files_struct *files;
- task_lock (task);
+ task_lock(task);
files = task->files;
if (files)
- atomic_inc (&files->count);
- task_unlock (task);
+ atomic_inc(&files->count);
+ task_unlock(task);
return files;
}
* put_files_struct is extracted from fs/file.c
*/
void
-put_files_struct (struct files_struct *files)
+put_files_struct(struct files_struct *files)
{
- if (atomic_dec_and_test (&files->count))
- {
- BUG ();
- }
+ if (atomic_dec_and_test(&files->count))
+ BUG();
}
static long
-eventfd_link_ioctl (struct file *f, unsigned int ioctl, unsigned long arg)
+eventfd_link_ioctl(struct file *f, unsigned int ioctl, unsigned long arg)
{
void __user *argp = (void __user *) arg;
struct task_struct *task_target = NULL;
struct fdtable *fdt;
struct eventfd_copy eventfd_copy;
- switch (ioctl)
- {
- case EVENTFD_COPY:
- if (copy_from_user (&eventfd_copy, argp, sizeof (struct eventfd_copy)))
- return -EFAULT;
-
- /*
- * Find the task struct for the target pid
- */
- task_target =
- pid_task (find_vpid (eventfd_copy.target_pid), PIDTYPE_PID);
- if (task_target == NULL)
- {
- printk (KERN_DEBUG "Failed to get mem ctx for target pid\n");
- return -EFAULT;
- }
-
- files = get_files_struct (current);
- if (files == NULL)
- {
- printk (KERN_DEBUG "Failed to get files struct\n");
- return -EFAULT;
- }
-
- rcu_read_lock ();
- file = fcheck_files (files, eventfd_copy.source_fd);
- if (file)
- {
- if (file->f_mode & FMODE_PATH
- || !atomic_long_inc_not_zero (&file->f_count))
- file = NULL;
- }
- rcu_read_unlock ();
- put_files_struct (files);
-
- if (file == NULL)
- {
- printk (KERN_DEBUG "Failed to get file from source pid\n");
- return 0;
- }
-
- /*
- * Release the existing eventfd in the source process
- */
- spin_lock (&files->file_lock);
- filp_close (file, files);
- fdt = files_fdtable (files);
- fdt->fd[eventfd_copy.source_fd] = NULL;
- spin_unlock (&files->file_lock);
-
- /*
- * Find the file struct associated with the target fd.
- */
-
- files = get_files_struct (task_target);
- if (files == NULL)
- {
- printk (KERN_DEBUG "Failed to get files struct\n");
- return -EFAULT;
- }
-
- rcu_read_lock ();
- file = fcheck_files (files, eventfd_copy.target_fd);
- if (file)
- {
- if (file->f_mode & FMODE_PATH
- || !atomic_long_inc_not_zero (&file->f_count))
+ switch (ioctl) {
+ case EVENTFD_COPY:
+ if (copy_from_user(&eventfd_copy, argp,
+ sizeof(struct eventfd_copy)))
+ return -EFAULT;
+
+ /*
+ * Find the task struct for the target pid
+ */
+ task_target =
+ pid_task(find_vpid(eventfd_copy.target_pid), PIDTYPE_PID);
+ if (task_target == NULL) {
+ pr_debug("Failed to get mem ctx for target pid\n");
+ return -EFAULT;
+ }
+
+ files = get_files_struct(current);
+ if (files == NULL) {
+ pr_debug("Failed to get files struct\n");
+ return -EFAULT;
+ }
+
+ rcu_read_lock();
+ file = fcheck_files(files, eventfd_copy.source_fd);
+ if (file) {
+ if (file->f_mode & FMODE_PATH ||
+ !atomic_long_inc_not_zero(&file->f_count))
+ file = NULL;
+ }
+ rcu_read_unlock();
+ put_files_struct(files);
+
+ if (file == NULL) {
+ pr_debug("Failed to get file from source pid\n");
+ return 0;
+ }
+
+ /*
+ * Release the existing eventfd in the source process
+ */
+ spin_lock(&files->file_lock);
+ filp_close(file, files);
+ fdt = files_fdtable(files);
+ fdt->fd[eventfd_copy.source_fd] = NULL;
+ spin_unlock(&files->file_lock);
+
+ /*
+ * Find the file struct associated with the target fd.
+ */
+
+ files = get_files_struct(task_target);
+ if (files == NULL) {
+ pr_debug("Failed to get files struct\n");
+ return -EFAULT;
+ }
+
+ rcu_read_lock();
+ file = fcheck_files(files, eventfd_copy.target_fd);
+ if (file) {
+ if (file->f_mode & FMODE_PATH ||
+ !atomic_long_inc_not_zero(&file->f_count))
file = NULL;
- }
- rcu_read_unlock ();
- put_files_struct (files);
-
- if (file == NULL)
- {
- printk (KERN_DEBUG "Failed to get file from target pid\n");
- return 0;
- }
+ }
+ rcu_read_unlock();
+ put_files_struct(files);
+ if (file == NULL) {
+ pr_debug("Failed to get file from target pid\n");
+ return 0;
+ }
- /*
- * Install the file struct from the target process into the
- * file desciptor of the source process,
- */
+ /*
+ * Install the file struct from the target process into the
+ * file desciptor of the source process,
+ */
- fd_install (eventfd_copy.source_fd, file);
+ fd_install(eventfd_copy.source_fd, file);
- return 0;
+ return 0;
- default:
- return -ENOIOCTLCMD;
+ default:
+ return -ENOIOCTLCMD;
}
}
};
static int __init
-eventfd_link_init (void)
+eventfd_link_init(void)
{
- return misc_register (&eventfd_link_misc);
+ return misc_register(&eventfd_link_misc);
}
-module_init (eventfd_link_init);
+module_init(eventfd_link_init);
static void __exit
-eventfd_link_exit (void)
+eventfd_link_exit(void)
{
- misc_deregister (&eventfd_link_misc);
+ misc_deregister(&eventfd_link_misc);
}
-module_exit (eventfd_link_exit);
+module_exit(eventfd_link_exit);
-MODULE_VERSION ("0.0.1");
-MODULE_LICENSE ("GPL v2");
-MODULE_AUTHOR ("Anthony Fee");
-MODULE_DESCRIPTION ("Link eventfd");
-MODULE_ALIAS ("devname:eventfd-link");
+MODULE_VERSION("0.0.1");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Anthony Fee");
+MODULE_DESCRIPTION("Link eventfd");
+MODULE_ALIAS("devname:eventfd-link");