[PATCH] xarray: fix kerneldoc for __xa_cmpxchg

[Christoph Hellwig <hch@lst.de>]

Fix the documentation for __xa_cmpxchg to actually describe the
cmpxch-like semantics correctly, based on the version for xa_cmpxchg.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 lib/xarray.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/lib/xarray.c b/lib/xarray.c
index 9644b18af18d..13a0781365ca 100644
--- a/lib/xarray.c
+++ b/lib/xarray.c
@@ -1742,21 +1742,27 @@ static inline void *__xa_cmpxchg_raw(struct xarray *xa, unsigned long index,
 			void *old, void *entry, gfp_t gfp);
 
 /**
- * __xa_cmpxchg() - Store this entry in the XArray.
+ * __xa_cmpxchg() - Conditionally replace an entry in the XArray.
  * @xa: XArray.
  * @index: Index into array.
  * @old: Old value to test against.
- * @entry: New entry.
+ * @entry: New value to place in array.
  * @gfp: Memory allocation flags.
  *
  * You must already be holding the xa_lock when calling this function.
  * It will drop the lock if needed to allocate memory, and then reacquire
  * it afterwards.
  *
+ * If the entry at @index is the same as @old, replace it with @entry.
+ * If the return value is equal to @old, then the exchange was successful.
+ *
  * Context: Any context.  Expects xa_lock to be held on entry.  May
  * release and reacquire xa_lock if @gfp flags permit.
- * Return: The old entry at this index or xa_err() if an error happened.
+ * Return: The old value at this index or xa_err() if an error happened.
  */
+static inline void *xa_cmpxchg(struct xarray *xa, unsigned long index,
+			void *old, void *entry, gfp_t gfp)
+{
 void *__xa_cmpxchg(struct xarray *xa, unsigned long index,
 			void *old, void *entry, gfp_t gfp)
 {
-- 
2.47.2