From: Rafael J. Wysocki Date: Wed, 9 Nov 2005 05:34:39 +0000 (-0800) Subject: [PATCH] swsusp: reduce code duplication X-Git-Tag: v2.6.15-rc1~384 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=054bd4c18853f3a3851bd97aa90e11022a69dc42;p=linux-2.6 [PATCH] swsusp: reduce code duplication The changes made by this patch are necessary for the pagedir relocation simplification in the next patch.  Additionally, these changes allow us to drop check_pagedir() and make get_safe_page() be a one-line wrapper around alloc_image_page() (get_safe_page() goes to snapshot.c, because alloc_image_page() is static and it does not make sense to export it). Signed-off-by: Rafael J. Wysocki Cc: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/kernel/power/power.h b/kernel/power/power.h index d4fd96a135..c98923e13e 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -66,7 +66,8 @@ extern asmlinkage int swsusp_arch_suspend(void); extern asmlinkage int swsusp_arch_resume(void); extern int restore_highmem(void); -extern struct pbe * alloc_pagedir(unsigned nr_pages); +extern struct pbe *alloc_pagedir(unsigned nr_pages, gfp_t gfp_mask, int safe_needed); extern void create_pbe_list(struct pbe *pblist, unsigned nr_pages); extern void swsusp_free(void); +extern int alloc_data_pages(struct pbe *pblist, gfp_t gfp_mask, int safe_needed); extern int enough_swap(unsigned nr_pages); diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 723f517988..96cc3e21e9 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -269,9 +269,30 @@ void create_pbe_list(struct pbe *pblist, unsigned int nr_pages) pr_debug("create_pbe_list(): initialized %d PBEs\n", num); } -static void *alloc_image_page(void) +/** + * @safe_needed - on resume, for storing the PBE list and the image, + * we can only use memory pages that do not conflict with the pages + * which had been used before suspend. + * + * The unsafe pages are marked with the PG_nosave_free flag + * + * Allocated but unusable (ie eaten) memory pages should be marked + * so that swsusp_free() can release them + */ + +static inline void *alloc_image_page(gfp_t gfp_mask, int safe_needed) { - void *res = (void *)get_zeroed_page(GFP_ATOMIC | __GFP_COLD); + void *res; + + if (safe_needed) + do { + res = (void *)get_zeroed_page(gfp_mask); + if (res && PageNosaveFree(virt_to_page(res))) + /* This is for swsusp_free() */ + SetPageNosave(virt_to_page(res)); + } while (res && PageNosaveFree(virt_to_page(res))); + else + res = (void *)get_zeroed_page(gfp_mask); if (res) { SetPageNosave(virt_to_page(res)); SetPageNosaveFree(virt_to_page(res)); @@ -279,6 +300,11 @@ static void *alloc_image_page(void) return res; } +unsigned long get_safe_page(gfp_t gfp_mask) +{ + return (unsigned long)alloc_image_page(gfp_mask, 1); +} + /** * alloc_pagedir - Allocate the page directory. * @@ -292,7 +318,7 @@ static void *alloc_image_page(void) * On each page we set up a list of struct_pbe elements. */ -struct pbe *alloc_pagedir(unsigned int nr_pages) +struct pbe *alloc_pagedir(unsigned int nr_pages, gfp_t gfp_mask, int safe_needed) { unsigned int num; struct pbe *pblist, *pbe; @@ -301,12 +327,12 @@ struct pbe *alloc_pagedir(unsigned int nr_pages) return NULL; pr_debug("alloc_pagedir(): nr_pages = %d\n", nr_pages); - pblist = alloc_image_page(); + 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 += PB_PAGE_SKIP; - pbe->next = alloc_image_page(); + pbe->next = alloc_image_page(gfp_mask, safe_needed); } if (!pbe) { /* get_zeroed_page() failed */ free_pagedir(pblist); @@ -354,24 +380,32 @@ static int enough_free_mem(unsigned int nr_pages) (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE); } +int alloc_data_pages(struct pbe *pblist, gfp_t gfp_mask, int safe_needed) +{ + struct pbe *p; + + for_each_pbe (p, pblist) { + p->address = (unsigned long)alloc_image_page(gfp_mask, safe_needed); + if (!p->address) + return -ENOMEM; + } + return 0; +} static struct pbe *swsusp_alloc(unsigned int nr_pages) { - struct pbe *pblist, *p; + struct pbe *pblist; - if (!(pblist = alloc_pagedir(nr_pages))) { + if (!(pblist = alloc_pagedir(nr_pages, GFP_ATOMIC | __GFP_COLD, 0))) { printk(KERN_ERR "suspend: Allocating pagedir failed.\n"); return NULL; } create_pbe_list(pblist, nr_pages); - for_each_pbe (p, pblist) { - p->address = (unsigned long)alloc_image_page(); - if (!p->address) { - printk(KERN_ERR "suspend: Allocating image pages failed.\n"); - swsusp_free(); - return NULL; - } + if (alloc_data_pages(pblist, GFP_ATOMIC | __GFP_COLD, 0)) { + printk(KERN_ERR "suspend: Allocating image pages failed.\n"); + swsusp_free(); + return NULL; } return pblist; diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index e1ab28b9b2..a456ffe7a3 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -628,59 +628,6 @@ int swsusp_resume(void) return error; } -/** - * On resume, for storing the PBE list and the image, - * we can only use memory pages that do not conflict with the pages - * which had been used before suspend. - * - * We don't know which pages are usable until we allocate them. - * - * Allocated but unusable (ie eaten) memory pages are marked so that - * swsusp_free() can release them - */ - -unsigned long get_safe_page(gfp_t gfp_mask) -{ - unsigned long m; - - do { - m = get_zeroed_page(gfp_mask); - if (m && PageNosaveFree(virt_to_page(m))) - /* This is for swsusp_free() */ - SetPageNosave(virt_to_page(m)); - } while (m && PageNosaveFree(virt_to_page(m))); - if (m) { - /* This is for swsusp_free() */ - SetPageNosave(virt_to_page(m)); - SetPageNosaveFree(virt_to_page(m)); - } - return m; -} - -/** - * check_pagedir - We ensure here that pages that the PBEs point to - * won't collide with pages where we're going to restore from the loaded - * pages later - */ - -static int check_pagedir(struct pbe *pblist) -{ - struct pbe *p; - - /* This is necessary, so that we can free allocated pages - * in case of failure - */ - for_each_pbe (p, pblist) - p->address = 0UL; - - for_each_pbe (p, pblist) { - p->address = get_safe_page(GFP_ATOMIC); - if (!p->address) - return -ENOMEM; - } - return 0; -} - /** * swsusp_pagedir_relocate - It is possible, that some memory pages * occupied by the list of PBEs collide with pages where we're going to @@ -990,7 +937,7 @@ static int read_suspend_image(void) int error = 0; struct pbe *p; - if (!(p = alloc_pagedir(nr_copy_pages))) + if (!(p = alloc_pagedir(nr_copy_pages, GFP_ATOMIC, 0))) return -ENOMEM; if ((error = read_pagedir(p))) @@ -1003,7 +950,7 @@ static int read_suspend_image(void) /* Allocate memory for the image and read the data from swap */ - error = check_pagedir(pagedir_nosave); + error = alloc_data_pages(pagedir_nosave, GFP_ATOMIC, 1); if (!error) error = data_read(pagedir_nosave);