From 43afc19417ca92cf237095947f597f21d86fd2a7 Mon Sep 17 00:00:00 2001 From: Vitaly Wool Date: Fri, 3 Jun 2016 14:55:47 -0700 Subject: [PATCH] mm/z3fold.c: avoid modifying HEADLESS page and minor cleanup Fix erroneous z3fold header access in a HEADLESS page in reclaim function, and change one remaining direct handle-to-buddy conversion to use the appropriate helper. Link: http://lkml.kernel.org/r/5748706F.9020208@gmail.com Signed-off-by: Vitaly Wool Reviewed-by: Dan Streetman Cc: Seth Jennings Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/z3fold.c | 24 ++++++++++++++---------- 1 file changed, 14 insertions(+), 10 deletions(-) diff --git a/mm/z3fold.c b/mm/z3fold.c index 34917d55d311..8f9e89ca1d31 100644 --- a/mm/z3fold.c +++ b/mm/z3fold.c @@ -412,7 +412,7 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle) /* HEADLESS page stored */ bud = HEADLESS; } else { - bud = (handle - zhdr->first_num) & BUDDY_MASK; + bud = handle_to_buddy(handle); switch (bud) { case FIRST: @@ -572,15 +572,19 @@ next: pool->pages_nr--; spin_unlock(&pool->lock); return 0; - } else if (zhdr->first_chunks != 0 && - zhdr->last_chunks != 0 && zhdr->middle_chunks != 0) { - /* Full, add to buddied list */ - list_add(&zhdr->buddy, &pool->buddied); - } else if (!test_bit(PAGE_HEADLESS, &page->private)) { - z3fold_compact_page(zhdr); - /* add to unbuddied list */ - freechunks = num_free_chunks(zhdr); - list_add(&zhdr->buddy, &pool->unbuddied[freechunks]); + } else if (!test_bit(PAGE_HEADLESS, &page->private)) { + if (zhdr->first_chunks != 0 && + zhdr->last_chunks != 0 && + zhdr->middle_chunks != 0) { + /* Full, add to buddied list */ + list_add(&zhdr->buddy, &pool->buddied); + } else { + z3fold_compact_page(zhdr); + /* add to unbuddied list */ + freechunks = num_free_chunks(zhdr); + list_add(&zhdr->buddy, + &pool->unbuddied[freechunks]); + } } /* add to beginning of LRU */ -- 2.39.5