From ad3fb6bab49a3d30c0f43d860df78253575d7e44 Mon Sep 17 00:00:00 2001 From: Gao Xiang Date: Wed, 13 Feb 2019 14:48:23 +0800 Subject: [PATCH] mm/readahead.c: simplify get_next_ra_size() mainline inclusion from mainline-5.0-rc1 commit 20ff1c950500380c6f74ec1a0d6f4eafab673ef6 category: bugfix bugzilla: 5928 CVE: NA ----------------------------- It's a trivial simplification for get_next_ra_size() and clear enough for humans to understand. It also fixes potential overflow if ra->size(< ra_pages) is too large. Link: http://lkml.kernel.org/r/1540707206-19649-1-git-send-email-hsiangkao@aol.com Signed-off-by: Gao Xiang Reviewed-by: Fengguang Wu Reviewed-by: Matthew Wilcox Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Jing xiangfeng Reviewed-by: Chen Wandun Signed-off-by: Yang Yingliang --- mm/readahead.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) diff --git a/mm/readahead.c b/mm/readahead.c index 4e630143a0ba..205ac348bb4a 100644 --- a/mm/readahead.c +++ b/mm/readahead.c @@ -272,17 +272,15 @@ static unsigned long get_init_ra_size(unsigned long size, unsigned long max) * return it as the new window size. */ static unsigned long get_next_ra_size(struct file_ra_state *ra, - unsigned long max) + unsigned long max) { unsigned long cur = ra->size; - unsigned long newsize; if (cur < max / 16) - newsize = 4 * cur; - else - newsize = 2 * cur; - - return min(newsize, max); + return 4 * cur; + if (cur <= max / 2) + return 2 * cur; + return max; } /* -- GitLab