From: Kent Overstreet <kent.overstreet@linux.dev>
To: linux-kernel@vger.kernel.org
Cc: Kent Overstreet <kent.overstreet@linux.dev>,
linux-aio@kvack.org, linux-fsdevel@vger.kernel.org
Subject: [PATCH 1/2] fs/aio: Use kmap_local() instead of kmap()
Date: Wed, 18 Jan 2023 10:26:02 -0500 [thread overview]
Message-ID: <20230118152603.28301-1-kent.overstreet@linux.dev> (raw)
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 5b2ff20ad3..3f795ed2a2 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1246,10 +1246,10 @@ 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;
--
2.39.0
next reply other threads:[~2023-01-18 15:55 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-18 15:26 Kent Overstreet [this message]
2023-01-18 15:26 ` [PATCH 2/2] fs/aio: obey min_nr when doing wakeups Kent Overstreet
2023-01-18 18:19 ` [PATCH 1/2] fs/aio: Use kmap_local() instead of kmap() Jeff Moyer
2023-01-20 14:03 ` [PATCH v2] fs/aio: obey min_nr when doing wakeups Kent Overstreet
2023-01-20 19:47 ` Jeff Moyer
2023-01-23 16:17 ` Jeff Moyer
2023-01-23 19:54 ` Kent Overstreet
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