From e94c1ea78329ed8c521d805d35edbeaceaee6317 Mon Sep 17 00:00:00 2001
From: Kent Overstreet <kent.overstreet@linux.dev>
Date: Wed, 18 Jan 2023 07:05:47 -0500
Subject: fs/aio: Use kmap_local() instead of kmap()

Originally, we used kmap() instead of kmap_atomic() for reading events
out of the completion ringbuffer because we're using copy_to_user(),
which can fault.

Now that kmap_local() is a thing, use that instead.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Cc: Benjamin LaHaise <bcrl@kvack.org
Cc: linux-aio@kvack.org
Cc: linux-fsdevel@vger.kernel.org
---
 fs/aio.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/aio.c b/fs/aio.c
index b0b17bd098bb..e1ba4b83998d 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1250,10 +1250,10 @@ static long aio_read_events_ring(struct kioctx *ctx,
 		avail = min(avail, nr - ret);
 		avail = min_t(long, avail, AIO_EVENTS_PER_PAGE - pos);
 
-		ev = kmap(page);
+		ev = kmap_local_page(page);
 		copy_ret = copy_to_user(event + ret, ev + pos,
 					sizeof(*ev) * avail);
-		kunmap(page);
+		kunmap_local(ev);
 
 		if (unlikely(copy_ret)) {
 			ret = -EFAULT;
-- 
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