ida: simplified functions for id allocation

The current hyper-optimized functions are overkill if you simply want to
allocate an id for a device.  Create versions which use an internal
lock.

In followup patches, numerous drivers are converted to use this
interface.

Thanks to Tejun for feedback.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/linux/idr.h b/include/linux/idr.h
index 13a801f3d028..255491cf522e 100644
--- a/include/linux/idr.h
+++ b/include/linux/idr.h
@@ -146,6 +146,10 @@ void ida_remove(struct ida *ida, int id);
 void ida_destroy(struct ida *ida);
 void ida_init(struct ida *ida);
 
+int ida_simple_get(struct ida *ida, unsigned int start, unsigned int end,
+                   gfp_t gfp_mask);
+void ida_simple_remove(struct ida *ida, unsigned int id);
+
 void __init idr_init_cache(void);
 
 #endif /* __IDR_H__ */