This is a note to let you know that I've just added the patch titled
NFSD: Clean up splice actor
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfsd-clean-up-splice-actor.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 965bfaf2f60ab42453f5486294f11a843b130821
Author: Chuck Lever <chuck.lever@xxxxxxxxxx>
Date: Mon Jun 28 16:34:20 2021 -0400
NFSD: Clean up splice actor
[ Upstream commit c7e0b781b73c2e26e442ed71397cc2bc5945a732 ]
A few useful observations:
- The value in @size is never modified.
- splice_desc.len is an unsigned int, and so is xdr_buf.page_len.
An implicit cast to size_t is unnecessary.
- The computation of .page_len is the same in all three arms
of the "if" statement, so hoist it out to make it clear that
the operation is an unconditional invariant.
The resulting function is 18 bytes shorter on my system (-Os).
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Reviewed-by: NeilBrown <neilb@xxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 74b2c6c5ad0b9..8520a2fc92dee 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -854,26 +854,21 @@ nfsd_splice_actor(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
struct svc_rqst *rqstp = sd->u.data;
struct page **pp = rqstp->rq_next_page;
struct page *page = buf->page;
- size_t size;
-
- size = sd->len;
if (rqstp->rq_res.page_len == 0) {
get_page(page);
put_page(*rqstp->rq_next_page);
*(rqstp->rq_next_page++) = page;
rqstp->rq_res.page_base = buf->offset;
- rqstp->rq_res.page_len = size;
} else if (page != pp[-1]) {
get_page(page);
if (*rqstp->rq_next_page)
put_page(*rqstp->rq_next_page);
*(rqstp->rq_next_page++) = page;
- rqstp->rq_res.page_len += size;
- } else
- rqstp->rq_res.page_len += size;
+ }
+ rqstp->rq_res.page_len += sd->len;
- return size;
+ return sd->len;
}
static int nfsd_direct_splice_actor(struct pipe_inode_info *pipe,
