diff --git a/arch/x86_64/kernel/e820.c b/arch/x86_64/kernel/e820.c index be89654..13c6c37 100644 --- a/arch/x86_64/kernel/e820.c +++ b/arch/x86_64/kernel/e820.c @@ -17,6 +17,8 @@ #include #include #include +#include +#include #include #include @@ -256,22 +258,6 @@ void __init e820_reserve_resources(void) } } -/* Mark pages corresponding to given address range as nosave */ -static void __init -e820_mark_nosave_range(unsigned long start, unsigned long end) -{ - unsigned long pfn, max_pfn; - - if (start >= end) - return; - - printk("Nosave address range: %016lx - %016lx\n", start, end); - max_pfn = end >> PAGE_SHIFT; - for (pfn = start >> PAGE_SHIFT; pfn < max_pfn; pfn++) - if (pfn_valid(pfn)) - SetPageNosave(pfn_to_page(pfn)); -} - /* * Find the ranges of physical addresses that do not correspond to * e820 RAM areas and mark the corresponding pages as nosave for software @@ -290,13 +276,13 @@ void __init e820_mark_nosave_regions(void) struct e820entry *ei = &e820.map[i]; if (paddr < ei->addr) - e820_mark_nosave_range(paddr, - round_up(ei->addr, PAGE_SIZE)); + register_nosave_region(PFN_DOWN(paddr), + PFN_UP(ei->addr)); paddr = round_down(ei->addr + ei->size, PAGE_SIZE); if (ei->type != E820_RAM) - e820_mark_nosave_range(round_up(ei->addr, PAGE_SIZE), - paddr); + register_nosave_region(PFN_UP(ei->addr), + PFN_DOWN(paddr)); if (paddr >= (end_pfn << PAGE_SHIFT)) break; diff --git a/include/linux/suspend.h b/include/linux/suspend.h index a45b9f5..3cc4d63 100644 --- a/include/linux/suspend.h +++ b/include/linux/suspend.h @@ -24,63 +24,41 @@ struct pbe { extern void drain_local_pages(void); extern void mark_free_pages(struct zone *zone); -#ifdef CONFIG_PM -/* kernel/power/swsusp.c */ -extern int software_suspend(void); - -#if defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE) +#if defined(CONFIG_PM) && defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE) extern int pm_prepare_console(void); extern void pm_restore_console(void); #else static inline int pm_prepare_console(void) { return 0; } static inline void pm_restore_console(void) {} -#endif /* defined(CONFIG_VT) && defined(CONFIG_VT_CONSOLE) */ +#endif + +#if defined(CONFIG_PM) && defined(CONFIG_SOFTWARE_SUSPEND) +/* kernel/power/swsusp.c */ +extern int software_suspend(void); +/* kernel/power/snapshot.c */ +extern void __init register_nosave_region(unsigned long, unsigned long); +extern int swsusp_page_is_forbidden(struct page *); +extern void swsusp_set_page_free(struct page *); +extern void swsusp_unset_page_free(struct page *); +extern unsigned long get_safe_page(gfp_t gfp_mask); #else static inline int software_suspend(void) { printk("Warning: fake suspend called\n"); return -ENOSYS; } -#endif /* CONFIG_PM */ + +static inline void register_nosave_region(unsigned long b, unsigned long e) {} +static inline int swsusp_page_is_forbidden(struct page *p) { return 0; } +static inline void swsusp_set_page_free(struct page *p) {} +static inline void swsusp_unset_page_free(struct page *p) {} +#endif /* defined(CONFIG_PM) && defined(CONFIG_SOFTWARE_SUSPEND) */ void save_processor_state(void); void restore_processor_state(void); struct saved_context; void __save_processor_state(struct saved_context *ctxt); void __restore_processor_state(struct saved_context *ctxt); -unsigned long get_safe_page(gfp_t gfp_mask); - -/* Page management functions for the software suspend (swsusp) */ - -static inline void swsusp_set_page_forbidden(struct page *page) -{ - SetPageNosave(page); -} - -static inline int swsusp_page_is_forbidden(struct page *page) -{ - return PageNosave(page); -} - -static inline void swsusp_unset_page_forbidden(struct page *page) -{ - ClearPageNosave(page); -} - -static inline void swsusp_set_page_free(struct page *page) -{ - SetPageNosaveFree(page); -} - -static inline int swsusp_page_is_free(struct page *page) -{ - return PageNosaveFree(page); -} - -static inline void swsusp_unset_page_free(struct page *page) -{ - ClearPageNosaveFree(page); -} /* * XXX: We try to keep some more pages free so that I/O operations succeed diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 8df51c2..403bc37 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -139,14 +139,19 @@ int pm_suspend_disk(void) mdelay(5000); goto Thaw; } + /* Allocate memory management structures */ + error = create_basic_memory_bitmaps(); + if (error) + goto Thaw; + /* Free memory before shutting down devices. */ error = swsusp_shrink_memory(); if (error) - goto Thaw; + goto Finish; error = platform_prepare(); if (error) - goto Thaw; + goto Finish; suspend_console(); error = device_suspend(PMSG_FREEZE); @@ -181,7 +186,7 @@ int pm_suspend_disk(void) power_down(); else { swsusp_free(); - goto Thaw; + goto Finish; } } else { pr_debug("PM: Image restored successfully.\n"); @@ -194,6 +199,8 @@ int pm_suspend_disk(void) platform_finish(); device_resume(); resume_console(); + Finish: + free_basic_memory_bitmaps(); Thaw: unprepare_processes(); return error; @@ -239,13 +246,15 @@ static int software_resume(void) } pr_debug("PM: Checking swsusp image.\n"); - error = swsusp_check(); if (error) - goto Done; + goto Unlock; - pr_debug("PM: Preparing processes for restore.\n"); + error = create_basic_memory_bitmaps(); + if (error) + goto Unlock; + pr_debug("PM: Preparing processes for restore.\n"); error = prepare_processes(); if (error) { swsusp_close(); @@ -280,7 +289,9 @@ static int software_resume(void) printk(KERN_ERR "PM: Restore failed, recovering.\n"); unprepare_processes(); Done: + free_basic_memory_bitmaps(); /* For success case, the suspend path will release the lock */ + Unlock: mutex_unlock(&pm_mutex); pr_debug("PM: Resume from disk failed.\n"); return 0; diff --git a/kernel/power/main.c b/kernel/power/main.c index b21c2a5..5a77927 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -244,6 +244,7 @@ static int enter_state(suspend_state_t state) return error; } +#ifdef CONFIG_SOFTWARE_SUSPEND /* * This is main interface to the outside world. It needs to be * called from process context. @@ -252,6 +253,7 @@ int software_suspend(void) { return enter_state(PM_SUSPEND_DISK); } +#endif /** diff --git a/kernel/power/power.h b/kernel/power/power.h index 33bd94c..1f8052b 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -48,6 +48,8 @@ extern sector_t swsusp_resume_block; extern asmlinkage int swsusp_arch_suspend(void); extern asmlinkage int swsusp_arch_resume(void); +extern int create_basic_memory_bitmaps(void); +extern void free_basic_memory_bitmaps(void); extern unsigned int count_data_pages(void); /** diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 48fc7a3..f66e441 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -21,6 +21,7 @@ #include #include #include +#include #include #include #include @@ -34,6 +35,10 @@ #include "power.h" +static int swsusp_page_is_free(struct page *); +static void swsusp_set_page_forbidden(struct page *); +static void swsusp_unset_page_forbidden(struct page *); + /* List of PBEs needed for restoring the pages that were allocated before * the suspend and included in the suspend image, but have also been * allocated by the "resume" kernel, so their contents cannot be written @@ -224,11 +229,6 @@ static void chain_free(struct chain_allocator *ca, int clear_page_nosave) * of type unsigned long each). It also contains the pfns that * correspond to the start and end of the represented memory area and * the number of bit chunks in the block. - * - * NOTE: Memory bitmaps are used for two types of operations only: - * "set a bit" and "find the next bit set". Moreover, the searching - * is always carried out after all of the "set a bit" operations - * on given bitmap. */ #define BM_END_OF_MAP (~0UL) @@ -443,15 +443,13 @@ static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free) } /** - * memory_bm_set_bit - set the bit in the bitmap @bm that corresponds + * memory_bm_find_bit - find the bit in the bitmap @bm that corresponds * to given pfn. The cur_zone_bm member of @bm and the cur_block member * of @bm->cur_zone_bm are updated. - * - * If the bit cannot be set, the function returns -EINVAL . */ -static int -memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn) +static void memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn, + void **addr, unsigned int *bit_nr) { struct zone_bitmap *zone_bm; struct bm_block *bb; @@ -463,8 +461,8 @@ memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn) /* We don't assume that the zones are sorted by pfns */ while (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) { zone_bm = zone_bm->next; - if (unlikely(!zone_bm)) - return -EINVAL; + + BUG_ON(!zone_bm); } bm->cur.zone_bm = zone_bm; } @@ -475,13 +473,40 @@ memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn) while (pfn >= bb->end_pfn) { bb = bb->next; - if (unlikely(!bb)) - return -EINVAL; + + BUG_ON(!bb); } zone_bm->cur_block = bb; pfn -= bb->start_pfn; - set_bit(pfn % BM_BITS_PER_CHUNK, bb->data + pfn / BM_BITS_PER_CHUNK); - return 0; + *bit_nr = pfn % BM_BITS_PER_CHUNK; + *addr = bb->data + pfn / BM_BITS_PER_CHUNK; +} + +static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn) +{ + void *addr; + unsigned int bit; + + memory_bm_find_bit(bm, pfn, &addr, &bit); + set_bit(bit, addr); +} + +static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn) +{ + void *addr; + unsigned int bit; + + memory_bm_find_bit(bm, pfn, &addr, &bit); + clear_bit(bit, addr); +} + +static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn) +{ + void *addr; + unsigned int bit; + + memory_bm_find_bit(bm, pfn, &addr, &bit); + return test_bit(bit, addr); } /* Two auxiliary functions for memory_bm_next_pfn */ @@ -564,6 +589,199 @@ static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm) } /** + * This structure represents a range of page frames the contents of which + * should not be saved during the suspend. + */ + +struct nosave_region { + struct list_head list; + unsigned long start_pfn; + unsigned long end_pfn; +}; + +static LIST_HEAD(nosave_regions); + +/** + * register_nosave_region - register a range of page frames the contents + * of which should not be saved during the suspend (to be used in the early + * initialization code) + */ + +void __init +register_nosave_region(unsigned long start_pfn, unsigned long end_pfn) +{ + struct nosave_region *region; + + if (start_pfn >= end_pfn) + return; + + if (!list_empty(&nosave_regions)) { + /* Try to extend the previous region (they should be sorted) */ + region = list_entry(nosave_regions.prev, + struct nosave_region, list); + if (region->end_pfn == start_pfn) { + region->end_pfn = end_pfn; + goto Report; + } + } + /* This allocation cannot fail */ + region = alloc_bootmem_low(sizeof(struct nosave_region)); + region->start_pfn = start_pfn; + region->end_pfn = end_pfn; + list_add_tail(®ion->list, &nosave_regions); + Report: + printk("swsusp: Registered nosave memory region: %016lx - %016lx\n", + start_pfn << PAGE_SHIFT, end_pfn << PAGE_SHIFT); +} + +/* + * Set bits in this map correspond to the page frames the contents of which + * should not be saved during the suspend. + */ +static struct memory_bitmap *forbidden_pages_map; + +/* Set bits in this map correspond to free page frames. */ +static struct memory_bitmap *free_pages_map; + +/* + * Each page frame allocated for creating the image is marked by setting the + * corresponding bits in forbidden_pages_map and free_pages_map simultaneously + */ + +void swsusp_set_page_free(struct page *page) +{ + if (free_pages_map) + memory_bm_set_bit(free_pages_map, page_to_pfn(page)); +} + +static int swsusp_page_is_free(struct page *page) +{ + return free_pages_map ? + memory_bm_test_bit(free_pages_map, page_to_pfn(page)) : 0; +} + +void swsusp_unset_page_free(struct page *page) +{ + if (free_pages_map) + memory_bm_clear_bit(free_pages_map, page_to_pfn(page)); +} + +static void swsusp_set_page_forbidden(struct page *page) +{ + if (forbidden_pages_map) + memory_bm_set_bit(forbidden_pages_map, page_to_pfn(page)); +} + +int swsusp_page_is_forbidden(struct page *page) +{ + return forbidden_pages_map ? + memory_bm_test_bit(forbidden_pages_map, page_to_pfn(page)) : 0; +} + +static void swsusp_unset_page_forbidden(struct page *page) +{ + if (forbidden_pages_map) + memory_bm_clear_bit(forbidden_pages_map, page_to_pfn(page)); +} + +/** + * mark_nosave_pages - set bits corresponding to the page frames the + * contents of which should not be saved in a given bitmap. + */ + +static void mark_nosave_pages(struct memory_bitmap *bm) +{ + struct nosave_region *region; + + if (list_empty(&nosave_regions)) + return; + + list_for_each_entry(region, &nosave_regions, list) { + unsigned long pfn; + + printk("swsusp: Marking nosave pages: %016lx - %016lx\n", + region->start_pfn << PAGE_SHIFT, + region->end_pfn << PAGE_SHIFT); + + for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++) + memory_bm_set_bit(bm, pfn); + } +} + +/** + * create_basic_memory_bitmaps - create bitmaps needed for marking page + * frames that should not be saved and free page frames. The pointers + * forbidden_pages_map and free_pages_map are only modified if everything + * goes well, because we don't want the bits to be used before both bitmaps + * are set up. + */ + +int create_basic_memory_bitmaps(void) +{ + struct memory_bitmap *bm1, *bm2; + int error = 0; + + BUG_ON(forbidden_pages_map || free_pages_map); + + bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_ATOMIC); + if (!bm1) + return -ENOMEM; + + error = memory_bm_create(bm1, GFP_ATOMIC | __GFP_COLD, PG_ANY); + if (error) + goto Free_first_object; + + bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_ATOMIC); + if (!bm2) + goto Free_first_bitmap; + + error = memory_bm_create(bm2, GFP_ATOMIC | __GFP_COLD, PG_ANY); + if (error) + goto Free_second_object; + + forbidden_pages_map = bm1; + free_pages_map = bm2; + mark_nosave_pages(forbidden_pages_map); + + printk("swsusp: Basic memory bitmaps created\n"); + + return 0; + + Free_second_object: + kfree(bm2); + Free_first_bitmap: + memory_bm_free(bm1, PG_UNSAFE_CLEAR); + Free_first_object: + kfree(bm1); + return -ENOMEM; +} + +/** + * free_basic_memory_bitmaps - free memory bitmaps allocated by + * create_basic_memory_bitmaps(). The auxiliary pointers are necessary + * so that the bitmaps themselves are not referred to while they are being + * freed. + */ + +void free_basic_memory_bitmaps(void) +{ + struct memory_bitmap *bm1, *bm2; + + BUG_ON(!(forbidden_pages_map && free_pages_map)); + + bm1 = forbidden_pages_map; + bm2 = free_pages_map; + forbidden_pages_map = NULL; + free_pages_map = NULL; + memory_bm_free(bm1, PG_UNSAFE_CLEAR); + kfree(bm1); + memory_bm_free(bm2, PG_UNSAFE_CLEAR); + kfree(bm2); + + printk("swsusp: Basic memory bitmaps freed\n"); +} + +/** * snapshot_additional_pages - estimate the number of additional pages * be needed for setting up the suspend image data structures for given * zone (usually the returned value is greater than the exact number) diff --git a/kernel/power/user.c b/kernel/power/user.c index 7cf6713..845acd8 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -52,6 +52,9 @@ static int snapshot_open(struct inode *inode, struct file *filp) if ((filp->f_flags & O_ACCMODE) == O_RDWR) return -ENOSYS; + if(create_basic_memory_bitmaps()) + return -ENOMEM; + nonseekable_open(inode, filp); data = &snapshot_state; filp->private_data = data; @@ -77,6 +80,7 @@ static int snapshot_release(struct inode *inode, struct file *filp) struct snapshot_data *data; swsusp_free(); + free_basic_memory_bitmaps(); data = filp->private_data; free_all_swap_pages(data->swap, data->bitmap); free_bitmap(data->bitmap);