fb: convert lock/unlock_kernel() into local fb mutex
Change lock_kernel()/unlock_kernel() to local fb mutex. Each frame buffer
instance has its own mutex.
The one line try_to_load() function is unrolled to request_module() in two
places for readability.
[righi.andrea@gmail.com: fb: fix NULL pointer BUG dereference in fb_open()]
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/fb.h b/include/linux/fb.h
index 531ccd5..75a81ea 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -808,6 +808,7 @@
struct fb_info {
int node;
int flags;
+ struct mutex lock; /* Lock for open/release/ioctl funcs */
struct fb_var_screeninfo var; /* Current var */
struct fb_fix_screeninfo fix; /* Current fix */
struct fb_monspecs monspecs; /* Current Monitor specs */