Commit 0cd189a4 authored by Dmitry Kalinkin's avatar Dmitry Kalinkin Committed by Greg Kroah-Hartman
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staging: vme: use image mutex for ioctl() 



This implements more granular locking in vme_user_ioctl() by using separate
locks for each devfs device.

This also provides a synchronization between vme_user_read(), vme_user_write()
and vme_user_ioctl().

Signed-off-by: default avatarDmitry Kalinkin <dmitry.kalinkin@gmail.com>
Cc: Martyn Welch <martyn.welch@ge.com>
Cc: Igor Alekseev <igor.alekseev@itep.ru>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent ad22d55c

drivers/staging/vme/devices/vme_user.c

+5 −4
Original line number Diff line number Diff line
@@ -41,7 +41,6 @@ 


#include "vme_user.h"



static DEFINE_MUTEX(vme_user_mutex);

static const char driver_name[] = "vme_user";



static int bus[VME_USER_BUS_MAX];
@@ -555,10 +554,12 @@ static long 
vme_user_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)

{

	int ret;

	struct inode *inode = file_inode(file);

	unsigned int minor = MINOR(inode->i_rdev);



	mutex_lock(&vme_user_mutex);

	ret = vme_user_ioctl(file_inode(file), file, cmd, arg);

	mutex_unlock(&vme_user_mutex);

	mutex_lock(&image[minor].mutex);

	ret = vme_user_ioctl(inode, file, cmd, arg);

	mutex_unlock(&image[minor].mutex);



	return ret;

}