From: Matthew Wilcox (Oracle) <willy@infradead.org>
Date: Fri, 9 Oct 2020 12:49:53 +0000 (+0100)
Subject: io_uring: Convert advanced XArray uses to the normal API
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=refs%2Fheads%2F5.8-stable;p=linux-2.6-block.git

io_uring: Convert advanced XArray uses to the normal API

commit 5e2ed8c4f45093698855b1f45cdf43efbf6dd498 upstream.

There are no bugs here that I've spotted, it's just easier to use the
normal API and there are no performance advantages to using the more
verbose advanced API.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 98f4c2789391..b27a8edde11f 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -7958,27 +7958,17 @@ static int io_uring_add_task_file(struct file *file)
 static void io_uring_del_task_file(struct file *file)
 {
 	struct io_uring_task *tctx = current->io_uring;
-	XA_STATE(xas, &tctx->xa, (unsigned long) file);
 
 	if (tctx->last == file)
 		tctx->last = NULL;
-
-	xas_lock(&xas);
-	file = xas_store(&xas, NULL);
-	xas_unlock(&xas);
-
+	file = xa_erase(&tctx->xa, (unsigned long)file);
 	if (file)
 		fput(file);
 }
 
 static void __io_uring_attempt_task_drop(struct file *file)
 {
-	XA_STATE(xas, &current->io_uring->xa, (unsigned long) file);
-	struct file *old;
-
-	rcu_read_lock();
-	old = xas_load(&xas);
-	rcu_read_unlock();
+	struct file *old = xa_load(&current->io_uring->xa, (unsigned long)file);
 
 	if (old == file)
 		io_uring_del_task_file(file);