lib/idr.c: document calling context for IDA APIs mustn't use locks

The documentation for these functions indicates that callers don't need to
hold a lock while calling them, but that documentation is only in one
place under "IDA Usage".  Let's state the same information on each IDA
function so that it's clear what the calling context requires.
Furthermore, let's document ida_simple_get() with the same information so
that callers know how this API works.

Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tri Vo <trong@android.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthew Wilcox <willy@infradead.org>
Link: https://lkml.kernel.org/r/20200910055246.2297797-1-swboyd@chromium.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 3 deletions

diff --git a/lib/idr.c b/lib/idr.c
index c2cf2c52bbde..3fa8be43696f 100644
--- a/lib/idr.c
+++ b/lib/idr.c
@@ -372,7 +372,8 @@ EXPORT_SYMBOL(idr_replace);
  * Allocate an ID between @min and @max, inclusive.  The allocated ID will
  * not exceed %INT_MAX, even if @max is larger.
  *
- * Context: Any context.
+ * Context: Any context. It is safe to call this function without
+ * locking in your code.
  * Return: The allocated ID, or %-ENOMEM if memory could not be allocated,
  * or %-ENOSPC if there are no free IDs.
  */
@@ -479,7 +480,8 @@ EXPORT_SYMBOL(ida_alloc_range);
  * @ida: IDA handle.
  * @id: Previously allocated ID.
  *
- * Context: Any context.
+ * Context: Any context. It is safe to call this function without
+ * locking in your code.
  */
 void ida_free(struct ida *ida, unsigned int id)
 {
@@ -531,7 +533,8 @@ EXPORT_SYMBOL(ida_free);
  * or freed.  If the IDA is already empty, there is no need to call this
  * function.
  *
- * Context: Any context.
+ * Context: Any context. It is safe to call this function without
+ * locking in your code.
  */
 void ida_destroy(struct ida *ida)
 {