diff options
| -rw-r--r-- | include/linux/swap.h | 8 | ||||
| -rw-r--r-- | kernel/power/hibernate.c | 1 | ||||
| -rw-r--r-- | kernel/power/snapshot.c | 1 | ||||
| -rw-r--r-- | kernel/power/swap.c | 6 | ||||
| -rw-r--r-- | mm/swapfile.c | 94 | 
5 files changed, 84 insertions, 26 deletions
diff --git a/include/linux/swap.h b/include/linux/swap.h index ff4acea9bbd..91c9d3fc851 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -316,7 +316,6 @@ extern long nr_swap_pages;  extern long total_swap_pages;  extern void si_swapinfo(struct sysinfo *);  extern swp_entry_t get_swap_page(void); -extern swp_entry_t get_swap_page_of_type(int);  extern int valid_swaphandles(swp_entry_t, unsigned long *);  extern int add_swap_count_continuation(swp_entry_t, gfp_t);  extern void swap_shmem_alloc(swp_entry_t); @@ -333,6 +332,13 @@ extern int reuse_swap_page(struct page *);  extern int try_to_free_swap(struct page *);  struct backing_dev_info; +#ifdef CONFIG_HIBERNATION +void hibernation_freeze_swap(void); +void hibernation_thaw_swap(void); +swp_entry_t get_swap_for_hibernation(int type); +void swap_free_for_hibernation(swp_entry_t val); +#endif +  /* linux/mm/thrash.c */  extern struct mm_struct *swap_token_mm;  extern void grab_swap_token(struct mm_struct *); diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 8dc31e02ae1..c77963938bc 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -338,6 +338,7 @@ int hibernation_snapshot(int platform_mode)  		goto Close;  	suspend_console(); +	hibernation_freeze_swap();  	saved_mask = clear_gfp_allowed_mask(GFP_IOFS);  	error = dpm_suspend_start(PMSG_FREEZE);  	if (error) diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index f6cd6faf84f..5e7edfb05e6 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -1086,6 +1086,7 @@ void swsusp_free(void)  	buffer = NULL;  	alloc_normal = 0;  	alloc_highmem = 0; +	hibernation_thaw_swap();  }  /* Helper functions used for the shrinking of memory. */ diff --git a/kernel/power/swap.c b/kernel/power/swap.c index e6a5bdf61a3..5d0059eed3e 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -136,10 +136,10 @@ sector_t alloc_swapdev_block(int swap)  {  	unsigned long offset; -	offset = swp_offset(get_swap_page_of_type(swap)); +	offset = swp_offset(get_swap_for_hibernation(swap));  	if (offset) {  		if (swsusp_extents_insert(offset)) -			swap_free(swp_entry(swap, offset)); +			swap_free_for_hibernation(swp_entry(swap, offset));  		else  			return swapdev_block(swap, offset);  	} @@ -163,7 +163,7 @@ void free_all_swap_pages(int swap)  		ext = container_of(node, struct swsusp_extent, node);  		rb_erase(node, &swsusp_extents);  		for (offset = ext->start; offset <= ext->end; offset++) -			swap_free(swp_entry(swap, offset)); +			swap_free_for_hibernation(swp_entry(swap, offset));  		kfree(ext);  	} diff --git a/mm/swapfile.c b/mm/swapfile.c index f08d165871b..1f3f9c59a73 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -47,6 +47,8 @@ long nr_swap_pages;  long total_swap_pages;  static int least_priority; +static bool swap_for_hibernation; +  static const char Bad_file[] = "Bad swap file entry ";  static const char Unused_file[] = "Unused swap file entry ";  static const char Bad_offset[] = "Bad swap offset entry "; @@ -451,6 +453,8 @@ swp_entry_t get_swap_page(void)  	spin_lock(&swap_lock);  	if (nr_swap_pages <= 0)  		goto noswap; +	if (swap_for_hibernation) +		goto noswap;  	nr_swap_pages--;  	for (type = swap_list.next; type >= 0 && wrapped < 2; type = next) { @@ -483,28 +487,6 @@ noswap:  	return (swp_entry_t) {0};  } -/* The only caller of this function is now susupend routine */ -swp_entry_t get_swap_page_of_type(int type) -{ -	struct swap_info_struct *si; -	pgoff_t offset; - -	spin_lock(&swap_lock); -	si = swap_info[type]; -	if (si && (si->flags & SWP_WRITEOK)) { -		nr_swap_pages--; -		/* This is called for allocating swap entry, not cache */ -		offset = scan_swap_map(si, 1); -		if (offset) { -			spin_unlock(&swap_lock); -			return swp_entry(type, offset); -		} -		nr_swap_pages++; -	} -	spin_unlock(&swap_lock); -	return (swp_entry_t) {0}; -} -  static struct swap_info_struct *swap_info_get(swp_entry_t entry)  {  	struct swap_info_struct *p; @@ -764,6 +746,74 @@ int mem_cgroup_count_swap_user(swp_entry_t ent, struct page **pagep)  #endif  #ifdef CONFIG_HIBERNATION + +static pgoff_t hibernation_offset[MAX_SWAPFILES]; +/* + * Once hibernation starts to use swap, we freeze swap_map[]. Otherwise, + * saved swap_map[] image to the disk will be an incomplete because it's + * changing without synchronization with hibernation snap shot. + * At resume, we just make swap_for_hibernation=false. We can forget + * used maps easily. + */ +void hibernation_freeze_swap(void) +{ +	int i; + +	spin_lock(&swap_lock); + +	printk(KERN_INFO "PM: Freeze Swap\n"); +	swap_for_hibernation = true; +	for (i = 0; i < MAX_SWAPFILES; i++) +		hibernation_offset[i] = 1; +	spin_unlock(&swap_lock); +} + +void hibernation_thaw_swap(void) +{ +	spin_lock(&swap_lock); +	if (swap_for_hibernation) { +		printk(KERN_INFO "PM: Thaw Swap\n"); +		swap_for_hibernation = false; +	} +	spin_unlock(&swap_lock); +} + +/* + * Because updateing swap_map[] can make not-saved-status-change, + * we use our own easy allocator. + * Please see kernel/power/swap.c, Used swaps are recorded into + * RB-tree. + */ +swp_entry_t get_swap_for_hibernation(int type) +{ +	pgoff_t off; +	swp_entry_t val = {0}; +	struct swap_info_struct *si; + +	spin_lock(&swap_lock); + +	si = swap_info[type]; +	if (!si || !(si->flags & SWP_WRITEOK)) +		goto done; + +	for (off = hibernation_offset[type]; off < si->max; ++off) { +		if (!si->swap_map[off]) +			break; +	} +	if (off < si->max) { +		val = swp_entry(type, off); +		hibernation_offset[type] = off + 1; +	} +done: +	spin_unlock(&swap_lock); +	return val; +} + +void swap_free_for_hibernation(swp_entry_t ent) +{ +	/* Nothing to do */ +} +  /*   * Find the swap type that corresponds to given device (if any).   *  |