summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAl Viro <viro@zeniv.linux.org.uk>2014-04-04 19:23:46 -0400
committerAl Viro <viro@zeniv.linux.org.uk>2014-05-06 17:39:45 -0400
commit81055e584f9d743cb13dc7944923d817c20f089d (patch)
tree06213185809c19175258bdb12f07204c79368cea
parent6abd232274fd652e4a57f486d14e52ffee6f72e9 (diff)
downloadlinux-81055e584f9d743cb13dc7944923d817c20f089d.tar.gz
optimize copy_page_{to,from}_iter()
if we'd ended up in the end of a segment, jump to the beginning of the next one (iov_offset = 0, iov++), rather than having the next primitive deal with that. Ought to be folded back... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-rw-r--r--mm/iov_iter.c8
1 files changed, 8 insertions, 0 deletions
diff --git a/mm/iov_iter.c b/mm/iov_iter.c
index 081e3273085b..fcdaaab438b6 100644
--- a/mm/iov_iter.c
+++ b/mm/iov_iter.c
@@ -74,6 +74,10 @@ size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes,
}
kunmap(page);
done:
+ if (skip == iov->iov_len) {
+ iov++;
+ skip = 0;
+ }
i->count -= wanted - bytes;
i->nr_segs -= iov - i->iov;
i->iov = iov;
@@ -152,6 +156,10 @@ size_t copy_page_from_iter(struct page *page, size_t offset, size_t bytes,
}
kunmap(page);
done:
+ if (skip == iov->iov_len) {
+ iov++;
+ skip = 0;
+ }
i->count -= wanted - bytes;
i->nr_segs -= iov - i->iov;
i->iov = iov;