From cd560bb2f9e2cd451bb3942af43da19632ba4a8e Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 25 Sep 2006 23:32:50 -0700 Subject: [PATCH] [PATCH] swsusp: Fix alloc_pagedir Get rid of the FIXME in kernel/power/snapshot.c#alloc_pagedir() and simplify the functions called by it. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/power/snapshot.c | 32 +++++++++++++++++--------------- 1 file changed, 17 insertions(+), 15 deletions(-) diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 7ad0c0465524..4ca372f2bc14 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -316,12 +316,12 @@ static void free_pagedir(struct pbe *pblist, int clear_nosave_free) * fill_pb_page - Create a list of PBEs on a given memory page */ -static inline void fill_pb_page(struct pbe *pbpage) +static inline void fill_pb_page(struct pbe *pbpage, unsigned int n) { struct pbe *p; p = pbpage; - pbpage += PB_PAGE_SKIP; + pbpage += n - 1; do p->next = p + 1; while (++p < pbpage); @@ -330,24 +330,26 @@ static inline void fill_pb_page(struct pbe *pbpage) /** * create_pbe_list - Create a list of PBEs on top of a given chain * of memory pages allocated with alloc_pagedir() + * + * This function assumes that pages allocated by alloc_image_page() will + * always be zeroed. */ static inline void create_pbe_list(struct pbe *pblist, unsigned int nr_pages) { - struct pbe *pbpage, *p; + struct pbe *pbpage; unsigned int num = PBES_PER_PAGE; for_each_pb_page (pbpage, pblist) { if (num >= nr_pages) break; - fill_pb_page(pbpage); + fill_pb_page(pbpage, PBES_PER_PAGE); num += PBES_PER_PAGE; } if (pbpage) { - for (num -= PBES_PER_PAGE - 1, p = pbpage; num < nr_pages; p++, num++) - p->next = p + 1; - p->next = NULL; + num -= PBES_PER_PAGE; + fill_pb_page(pbpage, nr_pages - num); } } @@ -374,17 +376,17 @@ static struct pbe *alloc_pagedir(unsigned int nr_pages, gfp_t gfp_mask, return NULL; pblist = alloc_image_page(gfp_mask, safe_needed); - /* FIXME: rewrite this ugly loop */ - for (pbe = pblist, num = PBES_PER_PAGE; pbe && num < nr_pages; - pbe = pbe->next, num += PBES_PER_PAGE) { + pbe = pblist; + for (num = PBES_PER_PAGE; num < nr_pages; num += PBES_PER_PAGE) { + if (!pbe) { + free_pagedir(pblist, 1); + return NULL; + } pbe += PB_PAGE_SKIP; pbe->next = alloc_image_page(gfp_mask, safe_needed); + pbe = pbe->next; } - if (!pbe) { /* get_zeroed_page() failed */ - free_pagedir(pblist, 1); - pblist = NULL; - } else - create_pbe_list(pblist, nr_pages); + create_pbe_list(pblist, nr_pages); return pblist; } -- 2.20.1