From 2c1b4a5ca48831595979a850f40ced8e7da026f8 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sun, 30 Oct 2005 14:59:58 -0800 Subject: [PATCH] swsusp: rework memory freeing on resume The following patch makes swsusp use the PG_nosave and PG_nosave_free flags to mark pages that should be freed in case of an error during resume. This allows us to simplify the code and to use swsusp_free() in all of the swsusp's resume error paths, which makes them actually work. Signed-off-by: Rafael J. Wysocki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86_64/kernel/suspend.c | 84 ++++++++++---------------------------------- 1 file changed, 19 insertions(+), 65 deletions(-) (limited to 'arch/x86_64/kernel/suspend.c') diff --git a/arch/x86_64/kernel/suspend.c b/arch/x86_64/kernel/suspend.c index 02516823f51..fd2bef78088 100644 --- a/arch/x86_64/kernel/suspend.c +++ b/arch/x86_64/kernel/suspend.c @@ -147,57 +147,7 @@ extern int restore_image(void); pgd_t *temp_level4_pgt; -static void **pages; - -static inline void *__add_page(void) -{ - void **c; - - c = (void **)get_usable_page(GFP_ATOMIC); - if (c) { - *c = pages; - pages = c; - } - return c; -} - -static inline void *__next_page(void) -{ - void **c; - - c = pages; - if (c) { - pages = *c; - *c = NULL; - } - return c; -} - -/* - * Try to allocate as many usable pages as needed and daisy chain them. - * If one allocation fails, free the pages allocated so far - */ -static int alloc_usable_pages(unsigned long n) -{ - void *p; - - pages = NULL; - do - if (!__add_page()) - break; - while (--n); - if (n) { - p = __next_page(); - while (p) { - free_page((unsigned long)p); - p = __next_page(); - } - return -ENOMEM; - } - return 0; -} - -static void res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long end) +static int res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long end) { long i, j; @@ -211,7 +161,9 @@ static void res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long e if (paddr >= end) break; - pmd = (pmd_t *)__next_page(); + pmd = (pmd_t *)get_safe_page(GFP_ATOMIC); + if (!pmd) + return -ENOMEM; set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE)); for (j = 0; j < PTRS_PER_PMD; pmd++, j++, paddr += PMD_SIZE) { unsigned long pe; @@ -223,13 +175,17 @@ static void res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long e set_pmd(pmd, __pmd(pe)); } } + return 0; } -static void set_up_temporary_mappings(void) +static int set_up_temporary_mappings(void) { unsigned long start, end, next; + int error; - temp_level4_pgt = (pgd_t *)__next_page(); + temp_level4_pgt = (pgd_t *)get_safe_page(GFP_ATOMIC); + if (!temp_level4_pgt) + return -ENOMEM; /* It is safe to reuse the original kernel mapping */ set_pgd(temp_level4_pgt + pgd_index(__START_KERNEL_map), @@ -240,29 +196,27 @@ static void set_up_temporary_mappings(void) end = (unsigned long)pfn_to_kaddr(end_pfn); for (; start < end; start = next) { - pud_t *pud = (pud_t *)__next_page(); + pud_t *pud = (pud_t *)get_safe_page(GFP_ATOMIC); + if (!pud) + return -ENOMEM; next = start + PGDIR_SIZE; if (next > end) next = end; - res_phys_pud_init(pud, __pa(start), __pa(next)); + if ((error = res_phys_pud_init(pud, __pa(start), __pa(next)))) + return error; set_pgd(temp_level4_pgt + pgd_index(start), mk_kernel_pgd(__pa(pud))); } + return 0; } int swsusp_arch_resume(void) { - unsigned long n; + int error; - n = ((end_pfn << PAGE_SHIFT) + PUD_SIZE - 1) >> PUD_SHIFT; - n += (n + PTRS_PER_PUD - 1) / PTRS_PER_PUD + 1; - pr_debug("swsusp_arch_resume(): pages needed = %lu\n", n); - if (alloc_usable_pages(n)) { - free_eaten_memory(); - return -ENOMEM; - } /* We have got enough memory and from now on we cannot recover */ - set_up_temporary_mappings(); + if ((error = set_up_temporary_mappings())) + return error; restore_image(); return 0; } -- cgit v1.2.3