From 2b322ce210aec74ae0d02938d3a01e29fe079469 Mon Sep 17 00:00:00 2001 From: Andrew Morton Date: Thu, 23 Mar 2006 02:59:58 -0800 Subject: [PATCH] revert "swsusp: fix breakage with swap on lvm" This was a temporary thing for 2.6.16. Cc: "Rafael J. Wysocki" Cc: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/power/swsusp.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'kernel/power/swsusp.c') diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index 2d9d08f72f7..4e90905f0e8 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -153,11 +153,13 @@ static int swsusp_swap_check(void) /* This is called before saving image */ { int i; + if (!swsusp_resume_device) + return -ENODEV; spin_lock(&swap_lock); for (i = 0; i < MAX_SWAPFILES; i++) { if (!(swap_info[i].flags & SWP_WRITEOK)) continue; - if (!swsusp_resume_device || is_resume_device(swap_info + i)) { + if (is_resume_device(swap_info + i)) { spin_unlock(&swap_lock); root_swap = i; return 0; -- cgit v1.2.3-70-g09d2 From f577eb30afdc68233f25d4d82b04102129262365 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 23 Mar 2006 02:59:59 -0800 Subject: [PATCH] swsusp: low level interface Introduce the low level interface that can be used for handling the snapshot of the system memory by the in-kernel swap-writing/reading code of swsusp and the userland interface code (to be introduced shortly). Also change the way in which swsusp records the allocated swap pages and, consequently, simplifies the in-kernel swap-writing/reading code (this is necessary for the userland interface too). To this end, it introduces two helper functions in mm/swapfile.c, so that the swsusp code does not refer directly to the swap internals. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Adrian Bunk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/swap.h | 5 +- kernel/power/disk.c | 12 +- kernel/power/power.h | 26 +- kernel/power/snapshot.c | 326 +++++++++++++++++++++- kernel/power/swsusp.c | 723 +++++++++++++++++------------------------------- mm/swapfile.c | 55 +++- 6 files changed, 656 insertions(+), 491 deletions(-) (limited to 'kernel/power/swsusp.c') diff --git a/include/linux/swap.h b/include/linux/swap.h index 12415dd9445..54eac8a39a4 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -234,14 +234,15 @@ extern struct page * read_swap_cache_async(swp_entry_t, struct vm_area_struct *v /* linux/mm/swapfile.c */ extern long total_swap_pages; extern unsigned int nr_swapfiles; -extern struct swap_info_struct swap_info[]; extern void si_swapinfo(struct sysinfo *); extern swp_entry_t get_swap_page(void); -extern swp_entry_t get_swap_page_of_type(int type); +extern swp_entry_t get_swap_page_of_type(int); extern int swap_duplicate(swp_entry_t); extern int valid_swaphandles(swp_entry_t, unsigned long *); extern void swap_free(swp_entry_t); extern void free_swap_and_cache(swp_entry_t); +extern int swap_type_of(dev_t); +extern unsigned int count_swap_pages(int, int); extern sector_t map_swap_page(struct swap_info_struct *, pgoff_t); extern struct swap_info_struct *get_swap_info_struct(unsigned); extern int can_share_swap_page(struct page *); diff --git a/kernel/power/disk.c b/kernel/power/disk.c index 0b43847dc98..4eb464b7134 100644 --- a/kernel/power/disk.c +++ b/kernel/power/disk.c @@ -26,9 +26,9 @@ extern suspend_disk_method_t pm_disk_mode; extern int swsusp_shrink_memory(void); extern int swsusp_suspend(void); -extern int swsusp_write(struct pbe *pblist, unsigned int nr_pages); +extern int swsusp_write(void); extern int swsusp_check(void); -extern int swsusp_read(struct pbe **pblist_ptr); +extern int swsusp_read(void); extern void swsusp_close(void); extern int swsusp_resume(void); @@ -70,10 +70,6 @@ static void power_down(suspend_disk_method_t mode) while(1); } - -static int in_suspend __nosavedata = 0; - - static inline void platform_finish(void) { if (pm_disk_mode == PM_DISK_PLATFORM) { @@ -145,7 +141,7 @@ int pm_suspend_disk(void) if (in_suspend) { device_resume(); pr_debug("PM: writing image.\n"); - error = swsusp_write(pagedir_nosave, nr_copy_pages); + error = swsusp_write(); if (!error) power_down(pm_disk_mode); else { @@ -216,7 +212,7 @@ static int software_resume(void) pr_debug("PM: Reading swsusp image.\n"); - if ((error = swsusp_read(&pagedir_nosave))) { + if ((error = swsusp_read())) { swsusp_free(); goto Thaw; } diff --git a/kernel/power/power.h b/kernel/power/power.h index 388dba68084..ea7132ed029 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -37,21 +37,31 @@ extern struct subsystem power_subsys; /* References to section boundaries */ extern const void __nosave_begin, __nosave_end; -extern unsigned int nr_copy_pages; extern struct pbe *pagedir_nosave; /* Preferred image size in bytes (default 500 MB) */ extern unsigned long image_size; +extern int in_suspend; + extern asmlinkage int swsusp_arch_suspend(void); extern asmlinkage int swsusp_arch_resume(void); extern unsigned int count_data_pages(void); -extern void free_pagedir(struct pbe *pblist); -extern void release_eaten_pages(void); -extern struct pbe *alloc_pagedir(unsigned nr_pages, gfp_t gfp_mask, int safe_needed); extern void swsusp_free(void); -extern int alloc_data_pages(struct pbe *pblist, gfp_t gfp_mask, int safe_needed); -extern unsigned int snapshot_nr_pages(void); -extern struct pbe *snapshot_pblist(void); -extern void snapshot_pblist_set(struct pbe *pblist); + +struct snapshot_handle { + loff_t offset; + unsigned int page; + unsigned int page_offset; + unsigned int prev; + struct pbe *pbe; + void *buffer; + unsigned int buf_offset; +}; + +#define data_of(handle) ((handle).buffer + (handle).buf_offset) + +extern int snapshot_read_next(struct snapshot_handle *handle, size_t count); +extern int snapshot_write_next(struct snapshot_handle *handle, size_t count); +int snapshot_image_loaded(struct snapshot_handle *handle); diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 8d5a5986d62..cc349437fb7 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -10,6 +10,7 @@ */ +#include #include #include #include @@ -34,7 +35,8 @@ #include "power.h" struct pbe *pagedir_nosave; -unsigned int nr_copy_pages; +static unsigned int nr_copy_pages; +static unsigned int nr_meta_pages; #ifdef CONFIG_HIGHMEM unsigned int count_highmem_pages(void) @@ -235,7 +237,7 @@ static void copy_data_pages(struct pbe *pblist) * free_pagedir - free pages allocated with alloc_pagedir() */ -void free_pagedir(struct pbe *pblist) +static void free_pagedir(struct pbe *pblist) { struct pbe *pbe; @@ -301,7 +303,7 @@ struct eaten_page { static struct eaten_page *eaten_pages = NULL; -void release_eaten_pages(void) +static void release_eaten_pages(void) { struct eaten_page *p, *q; @@ -376,7 +378,6 @@ struct pbe *alloc_pagedir(unsigned int nr_pages, gfp_t gfp_mask, int safe_needed if (!nr_pages) return NULL; - pr_debug("alloc_pagedir(): nr_pages = %d\n", nr_pages); pblist = alloc_image_page(gfp_mask, safe_needed); /* FIXME: rewrite this ugly loop */ for (pbe = pblist, num = PBES_PER_PAGE; pbe && num < nr_pages; @@ -414,6 +415,9 @@ void swsusp_free(void) } } } + nr_copy_pages = 0; + nr_meta_pages = 0; + pagedir_nosave = NULL; } @@ -437,7 +441,7 @@ 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) +static int alloc_data_pages(struct pbe *pblist, gfp_t gfp_mask, int safe_needed) { struct pbe *p; @@ -504,7 +508,319 @@ asmlinkage int swsusp_save(void) */ nr_copy_pages = nr_pages; + nr_meta_pages = (nr_pages * sizeof(long) + PAGE_SIZE - 1) >> PAGE_SHIFT; printk("swsusp: critical section/: done (%d pages copied)\n", nr_pages); return 0; } + +static void init_header(struct swsusp_info *info) +{ + memset(info, 0, sizeof(struct swsusp_info)); + info->version_code = LINUX_VERSION_CODE; + info->num_physpages = num_physpages; + memcpy(&info->uts, &system_utsname, sizeof(system_utsname)); + info->cpus = num_online_cpus(); + info->image_pages = nr_copy_pages; + info->pages = nr_copy_pages + nr_meta_pages + 1; +} + +/** + * pack_orig_addresses - the .orig_address fields of the PBEs from the + * list starting at @pbe are stored in the array @buf[] (1 page) + */ + +static inline struct pbe *pack_orig_addresses(unsigned long *buf, struct pbe *pbe) +{ + int j; + + for (j = 0; j < PAGE_SIZE / sizeof(long) && pbe; j++) { + buf[j] = pbe->orig_address; + pbe = pbe->next; + } + if (!pbe) + for (; j < PAGE_SIZE / sizeof(long); j++) + buf[j] = 0; + return pbe; +} + +/** + * snapshot_read_next - used for reading the system memory snapshot. + * + * On the first call to it @handle should point to a zeroed + * snapshot_handle structure. The structure gets updated and a pointer + * to it should be passed to this function every next time. + * + * The @count parameter should contain the number of bytes the caller + * wants to read from the snapshot. It must not be zero. + * + * On success the function returns a positive number. Then, the caller + * is allowed to read up to the returned number of bytes from the memory + * location computed by the data_of() macro. The number returned + * may be smaller than @count, but this only happens if the read would + * cross a page boundary otherwise. + * + * The function returns 0 to indicate the end of data stream condition, + * and a negative number is returned on error. In such cases the + * structure pointed to by @handle is not updated and should not be used + * any more. + */ + +int snapshot_read_next(struct snapshot_handle *handle, size_t count) +{ + static unsigned long *buffer; + + if (handle->page > nr_meta_pages + nr_copy_pages) + return 0; + if (!buffer) { + /* This makes the buffer be freed by swsusp_free() */ + buffer = alloc_image_page(GFP_ATOMIC, 0); + if (!buffer) + return -ENOMEM; + } + if (!handle->offset) { + init_header((struct swsusp_info *)buffer); + handle->buffer = buffer; + handle->pbe = pagedir_nosave; + } + if (handle->prev < handle->page) { + if (handle->page <= nr_meta_pages) { + handle->pbe = pack_orig_addresses(buffer, handle->pbe); + if (!handle->pbe) + handle->pbe = pagedir_nosave; + } else { + handle->buffer = (void *)handle->pbe->address; + handle->pbe = handle->pbe->next; + } + handle->prev = handle->page; + } + handle->buf_offset = handle->page_offset; + if (handle->page_offset + count >= PAGE_SIZE) { + count = PAGE_SIZE - handle->page_offset; + handle->page_offset = 0; + handle->page++; + } else { + handle->page_offset += count; + } + handle->offset += count; + return count; +} + +/** + * mark_unsafe_pages - mark the pages that cannot be used for storing + * the image during resume, because they conflict with the pages that + * had been used before suspend + */ + +static int mark_unsafe_pages(struct pbe *pblist) +{ + struct zone *zone; + unsigned long zone_pfn; + struct pbe *p; + + if (!pblist) /* a sanity check */ + return -EINVAL; + + /* Clear page flags */ + for_each_zone (zone) { + for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) + if (pfn_valid(zone_pfn + zone->zone_start_pfn)) + ClearPageNosaveFree(pfn_to_page(zone_pfn + + zone->zone_start_pfn)); + } + + /* Mark orig addresses */ + for_each_pbe (p, pblist) { + if (virt_addr_valid(p->orig_address)) + SetPageNosaveFree(virt_to_page(p->orig_address)); + else + return -EFAULT; + } + + return 0; +} + +static void copy_page_backup_list(struct pbe *dst, struct pbe *src) +{ + /* We assume both lists contain the same number of elements */ + while (src) { + dst->orig_address = src->orig_address; + dst = dst->next; + src = src->next; + } +} + +static int check_header(struct swsusp_info *info) +{ + char *reason = NULL; + + if (info->version_code != LINUX_VERSION_CODE) + reason = "kernel version"; + if (info->num_physpages != num_physpages) + reason = "memory size"; + if (strcmp(info->uts.sysname,system_utsname.sysname)) + reason = "system type"; + if (strcmp(info->uts.release,system_utsname.release)) + reason = "kernel release"; + if (strcmp(info->uts.version,system_utsname.version)) + reason = "version"; + if (strcmp(info->uts.machine,system_utsname.machine)) + reason = "machine"; + if (reason) { + printk(KERN_ERR "swsusp: Resume mismatch: %s\n", reason); + return -EPERM; + } + return 0; +} + +/** + * load header - check the image header and copy data from it + */ + +static int load_header(struct snapshot_handle *handle, + struct swsusp_info *info) +{ + int error; + struct pbe *pblist; + + error = check_header(info); + if (!error) { + pblist = alloc_pagedir(info->image_pages, GFP_ATOMIC, 0); + if (!pblist) + return -ENOMEM; + pagedir_nosave = pblist; + handle->pbe = pblist; + nr_copy_pages = info->image_pages; + nr_meta_pages = info->pages - info->image_pages - 1; + } + return error; +} + +/** + * unpack_orig_addresses - copy the elements of @buf[] (1 page) to + * the PBEs in the list starting at @pbe + */ + +static inline struct pbe *unpack_orig_addresses(unsigned long *buf, + struct pbe *pbe) +{ + int j; + + for (j = 0; j < PAGE_SIZE / sizeof(long) && pbe; j++) { + pbe->orig_address = buf[j]; + pbe = pbe->next; + } + return pbe; +} + +/** + * create_image - use metadata contained in the PBE list + * pointed to by pagedir_nosave to mark the pages that will + * be overwritten in the process of restoring the system + * memory state from the image and allocate memory for + * the image avoiding these pages + */ + +static int create_image(struct snapshot_handle *handle) +{ + int error = 0; + struct pbe *p, *pblist; + + p = pagedir_nosave; + error = mark_unsafe_pages(p); + if (!error) { + pblist = alloc_pagedir(nr_copy_pages, GFP_ATOMIC, 1); + if (pblist) + copy_page_backup_list(pblist, p); + free_pagedir(p); + if (!pblist) + error = -ENOMEM; + } + if (!error) + error = alloc_data_pages(pblist, GFP_ATOMIC, 1); + if (!error) { + release_eaten_pages(); + pagedir_nosave = pblist; + } else { + pagedir_nosave = NULL; + handle->pbe = NULL; + nr_copy_pages = 0; + nr_meta_pages = 0; + } + return error; +} + +/** + * snapshot_write_next - used for writing the system memory snapshot. + * + * On the first call to it @handle should point to a zeroed + * snapshot_handle structure. The structure gets updated and a pointer + * to it should be passed to this function every next time. + * + * The @count parameter should contain the number of bytes the caller + * wants to write to the image. It must not be zero. + * + * On success the function returns a positive number. Then, the caller + * is allowed to write up to the returned number of bytes to the memory + * location computed by the data_of() macro. The number returned + * may be smaller than @count, but this only happens if the write would + * cross a page boundary otherwise. + * + * The function returns 0 to indicate the "end of file" condition, + * and a negative number is returned on error. In such cases the + * structure pointed to by @handle is not updated and should not be used + * any more. + */ + +int snapshot_write_next(struct snapshot_handle *handle, size_t count) +{ + static unsigned long *buffer; + int error = 0; + + if (handle->prev && handle->page > nr_meta_pages + nr_copy_pages) + return 0; + if (!buffer) { + /* This makes the buffer be freed by swsusp_free() */ + buffer = alloc_image_page(GFP_ATOMIC, 0); + if (!buffer) + return -ENOMEM; + } + if (!handle->offset) + handle->buffer = buffer; + if (handle->prev < handle->page) { + if (!handle->prev) { + error = load_header(handle, (struct swsusp_info *)buffer); + if (error) + return error; + } else if (handle->prev <= nr_meta_pages) { + handle->pbe = unpack_orig_addresses(buffer, handle->pbe); + if (!handle->pbe) { + error = create_image(handle); + if (error) + return error; + handle->pbe = pagedir_nosave; + handle->buffer = (void *)handle->pbe->address; + } + } else { + handle->pbe = handle->pbe->next; + handle->buffer = (void *)handle->pbe->address; + } + handle->prev = handle->page; + } + handle->buf_offset = handle->page_offset; + if (handle->page_offset + count >= PAGE_SIZE) { + count = PAGE_SIZE - handle->page_offset; + handle->page_offset = 0; + handle->page++; + } else { + handle->page_offset += count; + } + handle->offset += count; + return count; +} + +int snapshot_image_loaded(struct snapshot_handle *handle) +{ + return !(!handle->pbe || handle->pbe->next || !nr_copy_pages || + handle->page <= nr_meta_pages + nr_copy_pages); +} diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index 4e90905f0e8..457084f5001 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -77,6 +77,8 @@ */ unsigned long image_size = 500 * 1024 * 1024; +int in_suspend __nosavedata = 0; + #ifdef CONFIG_HIGHMEM unsigned int count_highmem_pages(void); int save_highmem(void); @@ -98,8 +100,6 @@ static struct swsusp_header { char sig[10]; } __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header; -static struct swsusp_info swsusp_info; - /* * Saving part... */ @@ -129,255 +129,261 @@ static int mark_swapfiles(swp_entry_t start) return error; } -/* - * Check whether the swap device is the specified resume - * device, irrespective of whether they are specified by - * identical names. - * - * (Thus, device inode aliasing is allowed. You can say /dev/hda4 - * instead of /dev/ide/host0/bus0/target0/lun0/part4 [if using devfs] - * and they'll be considered the same device. This is *necessary* for - * devfs, since the resume code can only recognize the form /dev/hda4, - * but the suspend code would see the long name.) +/** + * swsusp_swap_check - check if the resume device is a swap device + * and get its index (if so) */ -static inline int is_resume_device(const struct swap_info_struct *swap_info) -{ - struct file *file = swap_info->swap_file; - struct inode *inode = file->f_dentry->d_inode; - - return S_ISBLK(inode->i_mode) && - swsusp_resume_device == MKDEV(imajor(inode), iminor(inode)); -} static int swsusp_swap_check(void) /* This is called before saving image */ { - int i; - - if (!swsusp_resume_device) - return -ENODEV; - spin_lock(&swap_lock); - for (i = 0; i < MAX_SWAPFILES; i++) { - if (!(swap_info[i].flags & SWP_WRITEOK)) - continue; - if (is_resume_device(swap_info + i)) { - spin_unlock(&swap_lock); - root_swap = i; - return 0; - } + int res = swap_type_of(swsusp_resume_device); + + if (res >= 0) { + root_swap = res; + return 0; } - spin_unlock(&swap_lock); - return -ENODEV; + return res; } /** - * write_page - Write one page to a fresh swap location. - * @addr: Address we're writing. - * @loc: Place to store the entry we used. + * The bitmap is used for tracing allocated swap pages * - * Allocate a new swap entry and 'sync' it. Note we discard -EIO - * errors. That is an artifact left over from swsusp. It did not - * check the return of rw_swap_page_sync() at all, since most pages - * written back to swap would return -EIO. - * This is a partial improvement, since we will at least return other - * errors, though we need to eventually fix the damn code. + * The entire bitmap consists of a number of bitmap_page + * structures linked with the help of the .next member. + * Thus each page can be allocated individually, so we only + * need to make 0-order memory allocations to create + * the bitmap. */ -static int write_page(unsigned long addr, swp_entry_t *loc) -{ - swp_entry_t entry; - int error = -ENOSPC; - entry = get_swap_page_of_type(root_swap); - if (swp_offset(entry)) { - error = rw_swap_page_sync(WRITE, entry, virt_to_page(addr)); - if (!error || error == -EIO) - *loc = entry; - } - return error; -} +#define BITMAP_PAGE_SIZE (PAGE_SIZE - sizeof(void *)) +#define BITMAP_PAGE_CHUNKS (BITMAP_PAGE_SIZE / sizeof(long)) +#define BITS_PER_CHUNK (sizeof(long) * 8) +#define BITMAP_PAGE_BITS (BITMAP_PAGE_CHUNKS * BITS_PER_CHUNK) + +struct bitmap_page { + unsigned long chunks[BITMAP_PAGE_CHUNKS]; + struct bitmap_page *next; +}; /** - * Swap map-handling functions + * The following functions are used for tracing the allocated + * swap pages, so that they can be freed in case of an error. * - * The swap map is a data structure used for keeping track of each page - * written to the swap. It consists of many swap_map_page structures - * that contain each an array of MAP_PAGE_SIZE swap entries. - * These structures are linked together with the help of either the - * .next (in memory) or the .next_swap (in swap) member. - * - * The swap map is created during suspend. At that time we need to keep - * it in memory, because we have to free all of the allocated swap - * entries if an error occurs. The memory needed is preallocated - * so that we know in advance if there's enough of it. - * - * The first swap_map_page structure is filled with the swap entries that - * correspond to the first MAP_PAGE_SIZE data pages written to swap and - * so on. After the all of the data pages have been written, the order - * of the swap_map_page structures in the map is reversed so that they - * can be read from swap in the original order. This causes the data - * pages to be loaded in exactly the same order in which they have been - * saved. - * - * During resume we only need to use one swap_map_page structure - * at a time, which means that we only need to use two memory pages for - * reading the image - one for reading the swap_map_page structures - * and the second for reading the data pages from swap. + * The functions operate on a linked bitmap structure defined + * above */ -#define MAP_PAGE_SIZE ((PAGE_SIZE - sizeof(swp_entry_t) - sizeof(void *)) \ - / sizeof(swp_entry_t)) - -struct swap_map_page { - swp_entry_t entries[MAP_PAGE_SIZE]; - swp_entry_t next_swap; - struct swap_map_page *next; -}; - -static inline void free_swap_map(struct swap_map_page *swap_map) +static void free_bitmap(struct bitmap_page *bitmap) { - struct swap_map_page *swp; + struct bitmap_page *bp; - while (swap_map) { - swp = swap_map->next; - free_page((unsigned long)swap_map); - swap_map = swp; + while (bitmap) { + bp = bitmap->next; + free_page((unsigned long)bitmap); + bitmap = bp; } } -static struct swap_map_page *alloc_swap_map(unsigned int nr_pages) +static struct bitmap_page *alloc_bitmap(unsigned int nr_bits) { - struct swap_map_page *swap_map, *swp; - unsigned n = 0; + struct bitmap_page *bitmap, *bp; + unsigned int n; - if (!nr_pages) + if (!nr_bits) return NULL; - pr_debug("alloc_swap_map(): nr_pages = %d\n", nr_pages); - swap_map = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC); - swp = swap_map; - for (n = MAP_PAGE_SIZE; n < nr_pages; n += MAP_PAGE_SIZE) { - swp->next = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC); - swp = swp->next; - if (!swp) { - free_swap_map(swap_map); + bitmap = (struct bitmap_page *)get_zeroed_page(GFP_KERNEL); + bp = bitmap; + for (n = BITMAP_PAGE_BITS; n < nr_bits; n += BITMAP_PAGE_BITS) { + bp->next = (struct bitmap_page *)get_zeroed_page(GFP_KERNEL); + bp = bp->next; + if (!bp) { + free_bitmap(bitmap); return NULL; } } - return swap_map; + return bitmap; } -/** - * reverse_swap_map - reverse the order of pages in the swap map - * @swap_map - */ - -static inline struct swap_map_page *reverse_swap_map(struct swap_map_page *swap_map) +static int bitmap_set(struct bitmap_page *bitmap, unsigned long bit) { - struct swap_map_page *prev, *next; - - prev = NULL; - while (swap_map) { - next = swap_map->next; - swap_map->next = prev; - prev = swap_map; - swap_map = next; + unsigned int n; + + n = BITMAP_PAGE_BITS; + while (bitmap && n <= bit) { + n += BITMAP_PAGE_BITS; + bitmap = bitmap->next; } - return prev; + if (!bitmap) + return -EINVAL; + n -= BITMAP_PAGE_BITS; + bit -= n; + n = 0; + while (bit >= BITS_PER_CHUNK) { + bit -= BITS_PER_CHUNK; + n++; + } + bitmap->chunks[n] |= (1UL << bit); + return 0; } -/** - * free_swap_map_entries - free the swap entries allocated to store - * the swap map @swap_map (this is only called in case of an error) - */ -static inline void free_swap_map_entries(struct swap_map_page *swap_map) +static unsigned long alloc_swap_page(int swap, struct bitmap_page *bitmap) { - while (swap_map) { - if (swap_map->next_swap.val) - swap_free(swap_map->next_swap); - swap_map = swap_map->next; + unsigned long offset; + + offset = swp_offset(get_swap_page_of_type(swap)); + if (offset) { + if (bitmap_set(bitmap, offset)) { + swap_free(swp_entry(swap, offset)); + offset = 0; + } } + return offset; } -/** - * save_swap_map - save the swap map used for tracing the data pages - * stored in the swap - */ - -static int save_swap_map(struct swap_map_page *swap_map, swp_entry_t *start) +static void free_all_swap_pages(int swap, struct bitmap_page *bitmap) { - swp_entry_t entry = (swp_entry_t){0}; - int error; + unsigned int bit, n; + unsigned long test; - while (swap_map) { - swap_map->next_swap = entry; - if ((error = write_page((unsigned long)swap_map, &entry))) - return error; - swap_map = swap_map->next; + bit = 0; + while (bitmap) { + for (n = 0; n < BITMAP_PAGE_CHUNKS; n++) + for (test = 1UL; test; test <<= 1) { + if (bitmap->chunks[n] & test) + swap_free(swp_entry(swap, bit)); + bit++; + } + bitmap = bitmap->next; } - *start = entry; - return 0; } /** - * free_image_entries - free the swap entries allocated to store - * the image data pages (this is only called in case of an error) + * write_page - Write one page to given swap location. + * @buf: Address we're writing. + * @offset: Offset of the swap page we're writing to. */ -static inline void free_image_entries(struct swap_map_page *swp) +static int write_page(void *buf, unsigned long offset) { - unsigned k; + swp_entry_t entry; + int error = -ENOSPC; - while (swp) { - for (k = 0; k < MAP_PAGE_SIZE; k++) - if (swp->entries[k].val) - swap_free(swp->entries[k]); - swp = swp->next; + if (offset) { + entry = swp_entry(root_swap, offset); + error = rw_swap_page_sync(WRITE, entry, virt_to_page(buf)); } + return error; } +/* + * The swap map is a data structure used for keeping track of each page + * written to a swap partition. It consists of many swap_map_page + * structures that contain each an array of MAP_PAGE_SIZE swap entries. + * These structures are stored on the swap and linked together with the + * help of the .next_swap member. + * + * The swap map is created during suspend. The swap map pages are + * allocated and populated one at a time, so we only need one memory + * page to set up the entire structure. + * + * During resume we also only need to use one swap_map_page structure + * at a time. + */ + +#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(long) - 1) + +struct swap_map_page { + unsigned long entries[MAP_PAGE_ENTRIES]; + unsigned long next_swap; +}; + /** - * The swap_map_handle structure is used for handling the swap map in + * The swap_map_handle structure is used for handling swap in * a file-alike way */ struct swap_map_handle { struct swap_map_page *cur; + unsigned long cur_swap; + struct bitmap_page *bitmap; unsigned int k; }; -static inline void init_swap_map_handle(struct swap_map_handle *handle, - struct swap_map_page *map) +static void release_swap_writer(struct swap_map_handle *handle) { - handle->cur = map; + if (handle->cur) + free_page((unsigned long)handle->cur); + handle->cur = NULL; + if (handle->bitmap) + free_bitmap(handle->bitmap); + handle->bitmap = NULL; +} + +static int get_swap_writer(struct swap_map_handle *handle) +{ + handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL); + if (!handle->cur) + return -ENOMEM; + handle->bitmap = alloc_bitmap(count_swap_pages(root_swap, 0)); + if (!handle->bitmap) { + release_swap_writer(handle); + return -ENOMEM; + } + handle->cur_swap = alloc_swap_page(root_swap, handle->bitmap); + if (!handle->cur_swap) { + release_swap_writer(handle); + return -ENOSPC; + } handle->k = 0; + return 0; } -static inline int swap_map_write_page(struct swap_map_handle *handle, - unsigned long addr) +static int swap_write_page(struct swap_map_handle *handle, void *buf) { int error; + unsigned long offset; - error = write_page(addr, handle->cur->entries + handle->k); + if (!handle->cur) + return -EINVAL; + offset = alloc_swap_page(root_swap, handle->bitmap); + error = write_page(buf, offset); if (error) return error; - if (++handle->k >= MAP_PAGE_SIZE) { - handle->cur = handle->cur->next; + handle->cur->entries[handle->k++] = offset; + if (handle->k >= MAP_PAGE_ENTRIES) { + offset = alloc_swap_page(root_swap, handle->bitmap); + if (!offset) + return -ENOSPC; + handle->cur->next_swap = offset; + error = write_page(handle->cur, handle->cur_swap); + if (error) + return error; + memset(handle->cur, 0, PAGE_SIZE); + handle->cur_swap = offset; handle->k = 0; } return 0; } +static int flush_swap_writer(struct swap_map_handle *handle) +{ + if (handle->cur && handle->cur_swap) + return write_page(handle->cur, handle->cur_swap); + else + return -EINVAL; +} + /** - * save_image_data - save the data pages pointed to by the PBEs - * from the list @pblist using the swap map handle @handle - * (assume there are @nr_pages data pages to save) + * save_image - save the suspend image data */ -static int save_image_data(struct pbe *pblist, - struct swap_map_handle *handle, - unsigned int nr_pages) +static int save_image(struct swap_map_handle *handle, + struct snapshot_handle *snapshot, + unsigned int nr_pages) { unsigned int m; - struct pbe *p; + int ret; int error = 0; printk("Saving image data pages (%u pages) ... ", nr_pages); @@ -385,98 +391,22 @@ static int save_image_data(struct pbe *pblist, if (!m) m = 1; nr_pages = 0; - for_each_pbe (p, pblist) { - error = swap_map_write_page(handle, p->address); - if (error) - break; - if (!(nr_pages % m)) - printk("\b\b\b\b%3d%%", nr_pages / m); - nr_pages++; - } + do { + ret = snapshot_read_next(snapshot, PAGE_SIZE); + if (ret > 0) { + error = swap_write_page(handle, data_of(*snapshot)); + if (error) + break; + if (!(nr_pages % m)) + printk("\b\b\b\b%3d%%", nr_pages / m); + nr_pages++; + } + } while (ret > 0); if (!error) printk("\b\b\b\bdone\n"); return error; } -static void dump_info(void) -{ - pr_debug(" swsusp: Version: %u\n",swsusp_info.version_code); - pr_debug(" swsusp: Num Pages: %ld\n",swsusp_info.num_physpages); - pr_debug(" swsusp: UTS Sys: %s\n",swsusp_info.uts.sysname); - pr_debug(" swsusp: UTS Node: %s\n",swsusp_info.uts.nodename); - pr_debug(" swsusp: UTS Release: %s\n",swsusp_info.uts.release); - pr_debug(" swsusp: UTS Version: %s\n",swsusp_info.uts.version); - pr_debug(" swsusp: UTS Machine: %s\n",swsusp_info.uts.machine); - pr_debug(" swsusp: UTS Domain: %s\n",swsusp_info.uts.domainname); - pr_debug(" swsusp: CPUs: %d\n",swsusp_info.cpus); - pr_debug(" swsusp: Image: %ld Pages\n",swsusp_info.image_pages); - pr_debug(" swsusp: Total: %ld Pages\n", swsusp_info.pages); -} - -static void init_header(unsigned int nr_pages) -{ - memset(&swsusp_info, 0, sizeof(swsusp_info)); - swsusp_info.version_code = LINUX_VERSION_CODE; - swsusp_info.num_physpages = num_physpages; - memcpy(&swsusp_info.uts, &system_utsname, sizeof(system_utsname)); - - swsusp_info.cpus = num_online_cpus(); - swsusp_info.image_pages = nr_pages; - swsusp_info.pages = nr_pages + - ((nr_pages * sizeof(long) + PAGE_SIZE - 1) >> PAGE_SHIFT) + 1; -} - -/** - * pack_orig_addresses - the .orig_address fields of the PBEs from the - * list starting at @pbe are stored in the array @buf[] (1 page) - */ - -static inline struct pbe *pack_orig_addresses(unsigned long *buf, - struct pbe *pbe) -{ - int j; - - for (j = 0; j < PAGE_SIZE / sizeof(long) && pbe; j++) { - buf[j] = pbe->orig_address; - pbe = pbe->next; - } - if (!pbe) - for (; j < PAGE_SIZE / sizeof(long); j++) - buf[j] = 0; - return pbe; -} - -/** - * save_image_metadata - save the .orig_address fields of the PBEs - * from the list @pblist using the swap map handle @handle - */ - -static int save_image_metadata(struct pbe *pblist, - struct swap_map_handle *handle) -{ - unsigned long *buf; - unsigned int n = 0; - struct pbe *p; - int error = 0; - - printk("Saving image metadata ... "); - buf = (unsigned long *)get_zeroed_page(GFP_ATOMIC); - if (!buf) - return -ENOMEM; - p = pblist; - while (p) { - p = pack_orig_addresses(buf, p); - error = swap_map_write_page(handle, (unsigned long)buf); - if (error) - break; - n++; - } - free_page((unsigned long)buf); - if (!error) - printk("done (%u pages saved)\n", n); - return error; -} - /** * enough_swap - Make sure we have enough swap to save the image. * @@ -486,8 +416,7 @@ static int save_image_metadata(struct pbe *pblist, static int enough_swap(unsigned int nr_pages) { - unsigned int free_swap = swap_info[root_swap].pages - - swap_info[root_swap].inuse_pages; + unsigned int free_swap = count_swap_pages(root_swap, 1); pr_debug("swsusp: free swap pages: %u\n", free_swap); return free_swap > (nr_pages + PAGES_FOR_IO + @@ -503,57 +432,44 @@ static int enough_swap(unsigned int nr_pages) * correctly, we'll mark system clean, anyway.) */ -int swsusp_write(struct pbe *pblist, unsigned int nr_pages) +int swsusp_write(void) { - struct swap_map_page *swap_map; struct swap_map_handle handle; - swp_entry_t start; + struct snapshot_handle snapshot; + struct swsusp_info *header; + unsigned long start; int error; if ((error = swsusp_swap_check())) { printk(KERN_ERR "swsusp: Cannot find swap device, try swapon -a.\n"); return error; } - if (!enough_swap(nr_pages)) { + memset(&snapshot, 0, sizeof(struct snapshot_handle)); + error = snapshot_read_next(&snapshot, PAGE_SIZE); + if (error < PAGE_SIZE) + return error < 0 ? error : -EFAULT; + header = (struct swsusp_info *)data_of(snapshot); + if (!enough_swap(header->pages)) { printk(KERN_ERR "swsusp: Not enough free swap\n"); return -ENOSPC; } - - init_header(nr_pages); - swap_map = alloc_swap_map(swsusp_info.pages); - if (!swap_map) - return -ENOMEM; - init_swap_map_handle(&handle, swap_map); - - error = swap_map_write_page(&handle, (unsigned long)&swsusp_info); - if (!error) - error = save_image_metadata(pblist, &handle); + error = get_swap_writer(&handle); + if (!error) { + start = handle.cur_swap; + error = swap_write_page(&handle, header); + } if (!error) - error = save_image_data(pblist, &handle, nr_pages); - if (error) - goto Free_image_entries; - - swap_map = reverse_swap_map(swap_map); - error = save_swap_map(swap_map, &start); - if (error) - goto Free_map_entries; - - dump_info(); - printk( "S" ); - error = mark_swapfiles(start); - printk( "|\n" ); + error = save_image(&handle, &snapshot, header->pages - 1); + if (!error) { + flush_swap_writer(&handle); + printk("S"); + error = mark_swapfiles(swp_entry(root_swap, start)); + printk("|\n"); + } if (error) - goto Free_map_entries; - -Free_swap_map: - free_swap_map(swap_map); + free_all_swap_pages(root_swap, handle.bitmap); + release_swap_writer(&handle); return error; - -Free_map_entries: - free_swap_map_entries(swap_map); -Free_image_entries: - free_image_entries(swap_map); - goto Free_swap_map; } /** @@ -663,45 +579,6 @@ int swsusp_resume(void) return error; } -/** - * mark_unsafe_pages - mark the pages that cannot be used for storing - * the image during resume, because they conflict with the pages that - * had been used before suspend - */ - -static void mark_unsafe_pages(struct pbe *pblist) -{ - struct zone *zone; - unsigned long zone_pfn; - struct pbe *p; - - if (!pblist) /* a sanity check */ - return; - - /* Clear page flags */ - for_each_zone (zone) { - for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) - if (pfn_valid(zone_pfn + zone->zone_start_pfn)) - ClearPageNosaveFree(pfn_to_page(zone_pfn + - zone->zone_start_pfn)); - } - - /* Mark orig addresses */ - for_each_pbe (p, pblist) - SetPageNosaveFree(virt_to_page(p->orig_address)); - -} - -static void copy_page_backup_list(struct pbe *dst, struct pbe *src) -{ - /* We assume both lists contain the same number of elements */ - while (src) { - dst->orig_address = src->orig_address; - dst = dst->next; - src = src->next; - } -} - /* * Using bio to read from swap. * This code requires a bit more work than just using buffer heads @@ -779,14 +656,14 @@ static int bio_write_page(pgoff_t page_off, void *page) * in a file-alike way */ -static inline void release_swap_map_reader(struct swap_map_handle *handle) +static void release_swap_reader(struct swap_map_handle *handle) { if (handle->cur) free_page((unsigned long)handle->cur); handle->cur = NULL; } -static inline int get_swap_map_reader(struct swap_map_handle *handle, +static int get_swap_reader(struct swap_map_handle *handle, swp_entry_t start) { int error; @@ -798,149 +675,80 @@ static inline int get_swap_map_reader(struct swap_map_handle *handle, return -ENOMEM; error = bio_read_page(swp_offset(start), handle->cur); if (error) { - release_swap_map_reader(handle); + release_swap_reader(handle); return error; } handle->k = 0; return 0; } -static inline int swap_map_read_page(struct swap_map_handle *handle, void *buf) +static int swap_read_page(struct swap_map_handle *handle, void *buf) { unsigned long offset; int error; if (!handle->cur) return -EINVAL; - offset = swp_offset(handle->cur->entries[handle->k]); + offset = handle->cur->entries[handle->k]; if (!offset) - return -EINVAL; + return -EFAULT; error = bio_read_page(offset, buf); if (error) return error; - if (++handle->k >= MAP_PAGE_SIZE) { + if (++handle->k >= MAP_PAGE_ENTRIES) { handle->k = 0; - offset = swp_offset(handle->cur->next_swap); + offset = handle->cur->next_swap; if (!offset) - release_swap_map_reader(handle); + release_swap_reader(handle); else error = bio_read_page(offset, handle->cur); } return error; } -static int check_header(void) -{ - char *reason = NULL; - - dump_info(); - if (swsusp_info.version_code != LINUX_VERSION_CODE) - reason = "kernel version"; - if (swsusp_info.num_physpages != num_physpages) - reason = "memory size"; - if (strcmp(swsusp_info.uts.sysname,system_utsname.sysname)) - reason = "system type"; - if (strcmp(swsusp_info.uts.release,system_utsname.release)) - reason = "kernel release"; - if (strcmp(swsusp_info.uts.version,system_utsname.version)) - reason = "version"; - if (strcmp(swsusp_info.uts.machine,system_utsname.machine)) - reason = "machine"; - if (reason) { - printk(KERN_ERR "swsusp: Resume mismatch: %s\n", reason); - return -EPERM; - } - return 0; -} - /** - * load_image_data - load the image data using the swap map handle - * @handle and store them using the page backup list @pblist + * load_image - load the image using the swap map handle + * @handle and the snapshot handle @snapshot * (assume there are @nr_pages pages to load) */ -static int load_image_data(struct pbe *pblist, - struct swap_map_handle *handle, - unsigned int nr_pages) +static int load_image(struct swap_map_handle *handle, + struct snapshot_handle *snapshot, + unsigned int nr_pages) { - int error; unsigned int m; - struct pbe *p; + int ret; + int error = 0; - if (!pblist) - return -EINVAL; printk("Loading image data pages (%u pages) ... ", nr_pages); m = nr_pages / 100; if (!m) m = 1; nr_pages = 0; - p = pblist; - while (p) { - error = swap_map_read_page(handle, (void *)p->address); - if (error) - break; - p = p->next; - if (!(nr_pages % m)) - printk("\b\b\b\b%3d%%", nr_pages / m); - nr_pages++; - } + do { + ret = snapshot_write_next(snapshot, PAGE_SIZE); + if (ret > 0) { + error = swap_read_page(handle, data_of(*snapshot)); + if (error) + break; + if (!(nr_pages % m)) + printk("\b\b\b\b%3d%%", nr_pages / m); + nr_pages++; + } + } while (ret > 0); if (!error) printk("\b\b\b\bdone\n"); + if (!snapshot_image_loaded(snapshot)) + error = -ENODATA; return error; } -/** - * unpack_orig_addresses - copy the elements of @buf[] (1 page) to - * the PBEs in the list starting at @pbe - */ - -static inline struct pbe *unpack_orig_addresses(unsigned long *buf, - struct pbe *pbe) -{ - int j; - - for (j = 0; j < PAGE_SIZE / sizeof(long) && pbe; j++) { - pbe->orig_address = buf[j]; - pbe = pbe->next; - } - return pbe; -} - -/** - * load_image_metadata - load the image metadata using the swap map - * handle @handle and put them into the PBEs in the list @pblist - */ - -static int load_image_metadata(struct pbe *pblist, struct swap_map_handle *handle) -{ - struct pbe *p; - unsigned long *buf; - unsigned int n = 0; - int error = 0; - - printk("Loading image metadata ... "); - buf = (unsigned long *)get_zeroed_page(GFP_ATOMIC); - if (!buf) - return -ENOMEM; - p = pblist; - while (p) { - error = swap_map_read_page(handle, buf); - if (error) - break; - p = unpack_orig_addresses(buf, p); - n++; - } - free_page((unsigned long)buf); - if (!error) - printk("done (%u pages loaded)\n", n); - return error; -} - -int swsusp_read(struct pbe **pblist_ptr) +int swsusp_read(void) { int error; - struct pbe *p, *pblist; struct swap_map_handle handle; + struct snapshot_handle snapshot; + struct swsusp_info *header; unsigned int nr_pages; if (IS_ERR(resume_bdev)) { @@ -948,38 +756,19 @@ int swsusp_read(struct pbe **pblist_ptr) return PTR_ERR(resume_bdev); } - error = get_swap_map_reader(&handle, swsusp_header.image); + memset(&snapshot, 0, sizeof(struct snapshot_handle)); + error = snapshot_write_next(&snapshot, PAGE_SIZE); + if (error < PAGE_SIZE) + return error < 0 ? error : -EFAULT; + header = (struct swsusp_info *)data_of(snapshot); + error = get_swap_reader(&handle, swsusp_header.image); if (!error) - error = swap_map_read_page(&handle, &swsusp_info); - if (!error) - error = check_header(); - if (error) - return error; - nr_pages = swsusp_info.image_pages; - p = alloc_pagedir(nr_pages, GFP_ATOMIC, 0); - if (!p) - return -ENOMEM; - error = load_image_metadata(p, &handle); + error = swap_read_page(&handle, header); if (!error) { - mark_unsafe_pages(p); - pblist = alloc_pagedir(nr_pages, GFP_ATOMIC, 1); - if (pblist) - copy_page_backup_list(pblist, p); - free_pagedir(p); - if (!pblist) - error = -ENOMEM; - - /* Allocate memory for the image and read the data from swap */ - if (!error) - error = alloc_data_pages(pblist, GFP_ATOMIC, 1); - if (!error) { - release_eaten_pages(); - error = load_image_data(pblist, &handle, nr_pages); - } - if (!error) - *pblist_ptr = pblist; + nr_pages = header->image_pages; + error = load_image(&handle, &snapshot, nr_pages); } - release_swap_map_reader(&handle); + release_swap_reader(&handle); blkdev_put(resume_bdev); diff --git a/mm/swapfile.c b/mm/swapfile.c index 365ed6ff182..4d11f9d8466 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -45,7 +45,7 @@ static const char Unused_offset[] = "Unused swap offset entry "; struct swap_list_t swap_list = {-1, -1}; -struct swap_info_struct swap_info[MAX_SWAPFILES]; +static struct swap_info_struct swap_info[MAX_SWAPFILES]; static DEFINE_MUTEX(swapon_mutex); @@ -417,6 +417,59 @@ void free_swap_and_cache(swp_entry_t entry) } } +#ifdef CONFIG_SOFTWARE_SUSPEND +/* + * Find the swap type that corresponds to given device (if any) + * + * This is needed for software suspend and is done in such a way that inode + * aliasing is allowed. + */ +int swap_type_of(dev_t device) +{ + int i; + + if (!device) + return -EINVAL; + spin_lock(&swap_lock); + for (i = 0; i < nr_swapfiles; i++) { + struct inode *inode; + + if (!(swap_info[i].flags & SWP_WRITEOK)) + continue; + inode = swap_info->swap_file->f_dentry->d_inode; + if (S_ISBLK(inode->i_mode) && + device == MKDEV(imajor(inode), iminor(inode))) { + spin_unlock(&swap_lock); + return i; + } + } + spin_unlock(&swap_lock); + return -ENODEV; +} + +/* + * Return either the total number of swap pages of given type, or the number + * of free pages of that type (depending on @free) + * + * This is needed for software suspend + */ +unsigned int count_swap_pages(int type, int free) +{ + unsigned int n = 0; + + if (type < nr_swapfiles) { + spin_lock(&swap_lock); + if (swap_info[type].flags & SWP_WRITEOK) { + n = swap_info[type].pages; + if (free) + n -= swap_info[type].inuse_pages; + } + spin_unlock(&swap_lock); + } + return n; +} +#endif + /* * No need to decide whether this PTE shares the swap entry with others, * just let do_wp_page work it out if a write is requested later - to -- cgit v1.2.3-70-g09d2 From 61159a314bca6408320c3173c1282c64f5cdaa76 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 23 Mar 2006 03:00:00 -0800 Subject: [PATCH] swsusp: separate swap-writing/reading code Move the swap-writing/reading code of swsusp to a separate file. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/power/Makefile | 2 +- kernel/power/power.h | 31 ++- kernel/power/swap.c | 544 +++++++++++++++++++++++++++++++++++++++++++++++ kernel/power/swsusp.c | 568 +------------------------------------------------- 4 files changed, 581 insertions(+), 564 deletions(-) create mode 100644 kernel/power/swap.c (limited to 'kernel/power/swsusp.c') diff --git a/kernel/power/Makefile b/kernel/power/Makefile index 04be7d0d96a..bb91a061530 100644 --- a/kernel/power/Makefile +++ b/kernel/power/Makefile @@ -5,7 +5,7 @@ endif obj-y := main.o process.o console.o obj-$(CONFIG_PM_LEGACY) += pm.o -obj-$(CONFIG_SOFTWARE_SUSPEND) += swsusp.o disk.o snapshot.o +obj-$(CONFIG_SOFTWARE_SUSPEND) += swsusp.o disk.o snapshot.o swap.o obj-$(CONFIG_SUSPEND_SMP) += smp.o diff --git a/kernel/power/power.h b/kernel/power/power.h index ea7132ed029..089c84bed89 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -41,8 +41,8 @@ extern struct pbe *pagedir_nosave; /* Preferred image size in bytes (default 500 MB) */ extern unsigned long image_size; - extern int in_suspend; +extern dev_t swsusp_resume_device; extern asmlinkage int swsusp_arch_suspend(void); extern asmlinkage int swsusp_arch_resume(void); @@ -65,3 +65,32 @@ struct snapshot_handle { extern int snapshot_read_next(struct snapshot_handle *handle, size_t count); extern int snapshot_write_next(struct snapshot_handle *handle, size_t count); int snapshot_image_loaded(struct snapshot_handle *handle); + +/** + * The bitmap is used for tracing allocated swap pages + * + * The entire bitmap consists of a number of bitmap_page + * structures linked with the help of the .next member. + * Thus each page can be allocated individually, so we only + * need to make 0-order memory allocations to create + * the bitmap. + */ + +#define BITMAP_PAGE_SIZE (PAGE_SIZE - sizeof(void *)) +#define BITMAP_PAGE_CHUNKS (BITMAP_PAGE_SIZE / sizeof(long)) +#define BITS_PER_CHUNK (sizeof(long) * 8) +#define BITMAP_PAGE_BITS (BITMAP_PAGE_CHUNKS * BITS_PER_CHUNK) + +struct bitmap_page { + unsigned long chunks[BITMAP_PAGE_CHUNKS]; + struct bitmap_page *next; +}; + +extern void free_bitmap(struct bitmap_page *bitmap); +extern struct bitmap_page *alloc_bitmap(unsigned int nr_bits); +extern unsigned long alloc_swap_page(int swap, struct bitmap_page *bitmap); +extern void free_all_swap_pages(int swap, struct bitmap_page *bitmap); + +extern int swsusp_shrink_memory(void); +extern int swsusp_suspend(void); +extern int swsusp_resume(void); diff --git a/kernel/power/swap.c b/kernel/power/swap.c new file mode 100644 index 00000000000..9177f3f73a6 --- /dev/null +++ b/kernel/power/swap.c @@ -0,0 +1,544 @@ +/* + * linux/kernel/power/swap.c + * + * This file provides functions for reading the suspend image from + * and writing it to a swap partition. + * + * Copyright (C) 1998,2001-2005 Pavel Machek + * Copyright (C) 2006 Rafael J. Wysocki + * + * This file is released under the GPLv2. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "power.h" + +extern char resume_file[]; + +#define SWSUSP_SIG "S1SUSPEND" + +static struct swsusp_header { + char reserved[PAGE_SIZE - 20 - sizeof(swp_entry_t)]; + swp_entry_t image; + char orig_sig[10]; + char sig[10]; +} __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header; + +/* + * Saving part... + */ + +static unsigned short root_swap = 0xffff; + +static int mark_swapfiles(swp_entry_t start) +{ + int error; + + rw_swap_page_sync(READ, + swp_entry(root_swap, 0), + virt_to_page((unsigned long)&swsusp_header)); + if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) || + !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) { + memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10); + memcpy(swsusp_header.sig,SWSUSP_SIG, 10); + swsusp_header.image = start; + error = rw_swap_page_sync(WRITE, + swp_entry(root_swap, 0), + virt_to_page((unsigned long) + &swsusp_header)); + } else { + pr_debug("swsusp: Partition is not swap space.\n"); + error = -ENODEV; + } + return error; +} + +/** + * swsusp_swap_check - check if the resume device is a swap device + * and get its index (if so) + */ + +static int swsusp_swap_check(void) /* This is called before saving image */ +{ + int res = swap_type_of(swsusp_resume_device); + + if (res >= 0) { + root_swap = res; + return 0; + } + return res; +} + +/** + * write_page - Write one page to given swap location. + * @buf: Address we're writing. + * @offset: Offset of the swap page we're writing to. + */ + +static int write_page(void *buf, unsigned long offset) +{ + swp_entry_t entry; + int error = -ENOSPC; + + if (offset) { + entry = swp_entry(root_swap, offset); + error = rw_swap_page_sync(WRITE, entry, virt_to_page(buf)); + } + return error; +} + +/* + * The swap map is a data structure used for keeping track of each page + * written to a swap partition. It consists of many swap_map_page + * structures that contain each an array of MAP_PAGE_SIZE swap entries. + * These structures are stored on the swap and linked together with the + * help of the .next_swap member. + * + * The swap map is created during suspend. The swap map pages are + * allocated and populated one at a time, so we only need one memory + * page to set up the entire structure. + * + * During resume we also only need to use one swap_map_page structure + * at a time. + */ + +#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(long) - 1) + +struct swap_map_page { + unsigned long entries[MAP_PAGE_ENTRIES]; + unsigned long next_swap; +}; + +/** + * The swap_map_handle structure is used for handling swap in + * a file-alike way + */ + +struct swap_map_handle { + struct swap_map_page *cur; + unsigned long cur_swap; + struct bitmap_page *bitmap; + unsigned int k; +}; + +static void release_swap_writer(struct swap_map_handle *handle) +{ + if (handle->cur) + free_page((unsigned long)handle->cur); + handle->cur = NULL; + if (handle->bitmap) + free_bitmap(handle->bitmap); + handle->bitmap = NULL; +} + +static int get_swap_writer(struct swap_map_handle *handle) +{ + handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL); + if (!handle->cur) + return -ENOMEM; + handle->bitmap = alloc_bitmap(count_swap_pages(root_swap, 0)); + if (!handle->bitmap) { + release_swap_writer(handle); + return -ENOMEM; + } + handle->cur_swap = alloc_swap_page(root_swap, handle->bitmap); + if (!handle->cur_swap) { + release_swap_writer(handle); + return -ENOSPC; + } + handle->k = 0; + return 0; +} + +static int swap_write_page(struct swap_map_handle *handle, void *buf) +{ + int error; + unsigned long offset; + + if (!handle->cur) + return -EINVAL; + offset = alloc_swap_page(root_swap, handle->bitmap); + error = write_page(buf, offset); + if (error) + return error; + handle->cur->entries[handle->k++] = offset; + if (handle->k >= MAP_PAGE_ENTRIES) { + offset = alloc_swap_page(root_swap, handle->bitmap); + if (!offset) + return -ENOSPC; + handle->cur->next_swap = offset; + error = write_page(handle->cur, handle->cur_swap); + if (error) + return error; + memset(handle->cur, 0, PAGE_SIZE); + handle->cur_swap = offset; + handle->k = 0; + } + return 0; +} + +static int flush_swap_writer(struct swap_map_handle *handle) +{ + if (handle->cur && handle->cur_swap) + return write_page(handle->cur, handle->cur_swap); + else + return -EINVAL; +} + +/** + * save_image - save the suspend image data + */ + +static int save_image(struct swap_map_handle *handle, + struct snapshot_handle *snapshot, + unsigned int nr_pages) +{ + unsigned int m; + int ret; + int error = 0; + + printk("Saving image data pages (%u pages) ... ", nr_pages); + m = nr_pages / 100; + if (!m) + m = 1; + nr_pages = 0; + do { + ret = snapshot_read_next(snapshot, PAGE_SIZE); + if (ret > 0) { + error = swap_write_page(handle, data_of(*snapshot)); + if (error) + break; + if (!(nr_pages % m)) + printk("\b\b\b\b%3d%%", nr_pages / m); + nr_pages++; + } + } while (ret > 0); + if (!error) + printk("\b\b\b\bdone\n"); + return error; +} + +/** + * enough_swap - Make sure we have enough swap to save the image. + * + * Returns TRUE or FALSE after checking the total amount of swap + * space avaiable from the resume partition. + */ + +static int enough_swap(unsigned int nr_pages) +{ + unsigned int free_swap = count_swap_pages(root_swap, 1); + + pr_debug("swsusp: free swap pages: %u\n", free_swap); + return free_swap > (nr_pages + PAGES_FOR_IO + + (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE); +} + +/** + * swsusp_write - Write entire image and metadata. + * + * It is important _NOT_ to umount filesystems at this point. We want + * them synced (in case something goes wrong) but we DO not want to mark + * filesystem clean: it is not. (And it does not matter, if we resume + * correctly, we'll mark system clean, anyway.) + */ + +int swsusp_write(void) +{ + struct swap_map_handle handle; + struct snapshot_handle snapshot; + struct swsusp_info *header; + unsigned long start; + int error; + + if ((error = swsusp_swap_check())) { + printk(KERN_ERR "swsusp: Cannot find swap device, try swapon -a.\n"); + return error; + } + memset(&snapshot, 0, sizeof(struct snapshot_handle)); + error = snapshot_read_next(&snapshot, PAGE_SIZE); + if (error < PAGE_SIZE) + return error < 0 ? error : -EFAULT; + header = (struct swsusp_info *)data_of(snapshot); + if (!enough_swap(header->pages)) { + printk(KERN_ERR "swsusp: Not enough free swap\n"); + return -ENOSPC; + } + error = get_swap_writer(&handle); + if (!error) { + start = handle.cur_swap; + error = swap_write_page(&handle, header); + } + if (!error) + error = save_image(&handle, &snapshot, header->pages - 1); + if (!error) { + flush_swap_writer(&handle); + printk("S"); + error = mark_swapfiles(swp_entry(root_swap, start)); + printk("|\n"); + } + if (error) + free_all_swap_pages(root_swap, handle.bitmap); + release_swap_writer(&handle); + return error; +} + +/* + * Using bio to read from swap. + * This code requires a bit more work than just using buffer heads + * but, it is the recommended way for 2.5/2.6. + * The following are to signal the beginning and end of I/O. Bios + * finish asynchronously, while we want them to happen synchronously. + * A simple atomic_t, and a wait loop take care of this problem. + */ + +static atomic_t io_done = ATOMIC_INIT(0); + +static int end_io(struct bio *bio, unsigned int num, int err) +{ + if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) + panic("I/O error reading memory image"); + atomic_set(&io_done, 0); + return 0; +} + +static struct block_device *resume_bdev; + +/** + * submit - submit BIO request. + * @rw: READ or WRITE. + * @off physical offset of page. + * @page: page we're reading or writing. + * + * Straight from the textbook - allocate and initialize the bio. + * If we're writing, make sure the page is marked as dirty. + * Then submit it and wait. + */ + +static int submit(int rw, pgoff_t page_off, void *page) +{ + int error = 0; + struct bio *bio; + + bio = bio_alloc(GFP_ATOMIC, 1); + if (!bio) + return -ENOMEM; + bio->bi_sector = page_off * (PAGE_SIZE >> 9); + bio->bi_bdev = resume_bdev; + bio->bi_end_io = end_io; + + if (bio_add_page(bio, virt_to_page(page), PAGE_SIZE, 0) < PAGE_SIZE) { + printk("swsusp: ERROR: adding page to bio at %ld\n",page_off); + error = -EFAULT; + goto Done; + } + + atomic_set(&io_done, 1); + submit_bio(rw | (1 << BIO_RW_SYNC), bio); + while (atomic_read(&io_done)) + yield(); + if (rw == READ) + bio_set_pages_dirty(bio); + Done: + bio_put(bio); + return error; +} + +static int bio_read_page(pgoff_t page_off, void *page) +{ + return submit(READ, page_off, page); +} + +static int bio_write_page(pgoff_t page_off, void *page) +{ + return submit(WRITE, page_off, page); +} + +/** + * The following functions allow us to read data using a swap map + * in a file-alike way + */ + +static void release_swap_reader(struct swap_map_handle *handle) +{ + if (handle->cur) + free_page((unsigned long)handle->cur); + handle->cur = NULL; +} + +static int get_swap_reader(struct swap_map_handle *handle, + swp_entry_t start) +{ + int error; + + if (!swp_offset(start)) + return -EINVAL; + handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC); + if (!handle->cur) + return -ENOMEM; + error = bio_read_page(swp_offset(start), handle->cur); + if (error) { + release_swap_reader(handle); + return error; + } + handle->k = 0; + return 0; +} + +static int swap_read_page(struct swap_map_handle *handle, void *buf) +{ + unsigned long offset; + int error; + + if (!handle->cur) + return -EINVAL; + offset = handle->cur->entries[handle->k]; + if (!offset) + return -EFAULT; + error = bio_read_page(offset, buf); + if (error) + return error; + if (++handle->k >= MAP_PAGE_ENTRIES) { + handle->k = 0; + offset = handle->cur->next_swap; + if (!offset) + release_swap_reader(handle); + else + error = bio_read_page(offset, handle->cur); + } + return error; +} + +/** + * load_image - load the image using the swap map handle + * @handle and the snapshot handle @snapshot + * (assume there are @nr_pages pages to load) + */ + +static int load_image(struct swap_map_handle *handle, + struct snapshot_handle *snapshot, + unsigned int nr_pages) +{ + unsigned int m; + int ret; + int error = 0; + + printk("Loading image data pages (%u pages) ... ", nr_pages); + m = nr_pages / 100; + if (!m) + m = 1; + nr_pages = 0; + do { + ret = snapshot_write_next(snapshot, PAGE_SIZE); + if (ret > 0) { + error = swap_read_page(handle, data_of(*snapshot)); + if (error) + break; + if (!(nr_pages % m)) + printk("\b\b\b\b%3d%%", nr_pages / m); + nr_pages++; + } + } while (ret > 0); + if (!error) + printk("\b\b\b\bdone\n"); + if (!snapshot_image_loaded(snapshot)) + error = -ENODATA; + return error; +} + +int swsusp_read(void) +{ + int error; + struct swap_map_handle handle; + struct snapshot_handle snapshot; + struct swsusp_info *header; + + if (IS_ERR(resume_bdev)) { + pr_debug("swsusp: block device not initialised\n"); + return PTR_ERR(resume_bdev); + } + + memset(&snapshot, 0, sizeof(struct snapshot_handle)); + error = snapshot_write_next(&snapshot, PAGE_SIZE); + if (error < PAGE_SIZE) + return error < 0 ? error : -EFAULT; + header = (struct swsusp_info *)data_of(snapshot); + error = get_swap_reader(&handle, swsusp_header.image); + if (!error) + error = swap_read_page(&handle, header); + if (!error) + error = load_image(&handle, &snapshot, header->pages - 1); + release_swap_reader(&handle); + + blkdev_put(resume_bdev); + + if (!error) + pr_debug("swsusp: Reading resume file was successful\n"); + else + pr_debug("swsusp: Error %d resuming\n", error); + return error; +} + +/** + * swsusp_check - Check for swsusp signature in the resume device + */ + +int swsusp_check(void) +{ + int error; + + resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ); + if (!IS_ERR(resume_bdev)) { + set_blocksize(resume_bdev, PAGE_SIZE); + memset(&swsusp_header, 0, sizeof(swsusp_header)); + if ((error = bio_read_page(0, &swsusp_header))) + return error; + if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) { + memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10); + /* Reset swap signature now */ + error = bio_write_page(0, &swsusp_header); + } else { + return -EINVAL; + } + if (error) + blkdev_put(resume_bdev); + else + pr_debug("swsusp: Signature found, resuming\n"); + } else { + error = PTR_ERR(resume_bdev); + } + + if (error) + pr_debug("swsusp: Error %d check for resume file\n", error); + + return error; +} + +/** + * swsusp_close - close swap device. + */ + +void swsusp_close(void) +{ + if (IS_ERR(resume_bdev)) { + pr_debug("swsusp: block device not initialised\n"); + return; + } + + blkdev_put(resume_bdev); +} diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index 457084f5001..c4016cbbd3e 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -31,41 +31,24 @@ * Fixed runaway init * * Rafael J. Wysocki - * Added the swap map data structure and reworked the handling of swap + * Reworked the freeing of memory and the handling of swap * * More state savers are welcome. Especially for the scsi layer... * * For TODOs,FIXMEs also look in Documentation/power/swsusp.txt */ -#include #include #include -#include -#include -#include -#include -#include -#include #include -#include #include #include #include #include -#include -#include #include #include #include #include -#include - -#include -#include -#include -#include -#include #include "power.h" @@ -89,91 +72,15 @@ static int restore_highmem(void) { return 0; } static unsigned int count_highmem_pages(void) { return 0; } #endif -extern char resume_file[]; - -#define SWSUSP_SIG "S1SUSPEND" - -static struct swsusp_header { - char reserved[PAGE_SIZE - 20 - sizeof(swp_entry_t)]; - swp_entry_t image; - char orig_sig[10]; - char sig[10]; -} __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header; - -/* - * Saving part... - */ - -static unsigned short root_swap = 0xffff; - -static int mark_swapfiles(swp_entry_t start) -{ - int error; - - rw_swap_page_sync(READ, - swp_entry(root_swap, 0), - virt_to_page((unsigned long)&swsusp_header)); - if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) || - !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) { - memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10); - memcpy(swsusp_header.sig,SWSUSP_SIG, 10); - swsusp_header.image = start; - error = rw_swap_page_sync(WRITE, - swp_entry(root_swap, 0), - virt_to_page((unsigned long) - &swsusp_header)); - } else { - pr_debug("swsusp: Partition is not swap space.\n"); - error = -ENODEV; - } - return error; -} - -/** - * swsusp_swap_check - check if the resume device is a swap device - * and get its index (if so) - */ - -static int swsusp_swap_check(void) /* This is called before saving image */ -{ - int res = swap_type_of(swsusp_resume_device); - - if (res >= 0) { - root_swap = res; - return 0; - } - return res; -} - -/** - * The bitmap is used for tracing allocated swap pages - * - * The entire bitmap consists of a number of bitmap_page - * structures linked with the help of the .next member. - * Thus each page can be allocated individually, so we only - * need to make 0-order memory allocations to create - * the bitmap. - */ - -#define BITMAP_PAGE_SIZE (PAGE_SIZE - sizeof(void *)) -#define BITMAP_PAGE_CHUNKS (BITMAP_PAGE_SIZE / sizeof(long)) -#define BITS_PER_CHUNK (sizeof(long) * 8) -#define BITMAP_PAGE_BITS (BITMAP_PAGE_CHUNKS * BITS_PER_CHUNK) - -struct bitmap_page { - unsigned long chunks[BITMAP_PAGE_CHUNKS]; - struct bitmap_page *next; -}; - /** * The following functions are used for tracing the allocated * swap pages, so that they can be freed in case of an error. * * The functions operate on a linked bitmap structure defined - * above + * in power.h */ -static void free_bitmap(struct bitmap_page *bitmap) +void free_bitmap(struct bitmap_page *bitmap) { struct bitmap_page *bp; @@ -184,7 +91,7 @@ static void free_bitmap(struct bitmap_page *bitmap) } } -static struct bitmap_page *alloc_bitmap(unsigned int nr_bits) +struct bitmap_page *alloc_bitmap(unsigned int nr_bits) { struct bitmap_page *bitmap, *bp; unsigned int n; @@ -227,7 +134,7 @@ static int bitmap_set(struct bitmap_page *bitmap, unsigned long bit) return 0; } -static unsigned long alloc_swap_page(int swap, struct bitmap_page *bitmap) +unsigned long alloc_swap_page(int swap, struct bitmap_page *bitmap) { unsigned long offset; @@ -241,7 +148,7 @@ static unsigned long alloc_swap_page(int swap, struct bitmap_page *bitmap) return offset; } -static void free_all_swap_pages(int swap, struct bitmap_page *bitmap) +void free_all_swap_pages(int swap, struct bitmap_page *bitmap) { unsigned int bit, n; unsigned long test; @@ -258,220 +165,6 @@ static void free_all_swap_pages(int swap, struct bitmap_page *bitmap) } } -/** - * write_page - Write one page to given swap location. - * @buf: Address we're writing. - * @offset: Offset of the swap page we're writing to. - */ - -static int write_page(void *buf, unsigned long offset) -{ - swp_entry_t entry; - int error = -ENOSPC; - - if (offset) { - entry = swp_entry(root_swap, offset); - error = rw_swap_page_sync(WRITE, entry, virt_to_page(buf)); - } - return error; -} - -/* - * The swap map is a data structure used for keeping track of each page - * written to a swap partition. It consists of many swap_map_page - * structures that contain each an array of MAP_PAGE_SIZE swap entries. - * These structures are stored on the swap and linked together with the - * help of the .next_swap member. - * - * The swap map is created during suspend. The swap map pages are - * allocated and populated one at a time, so we only need one memory - * page to set up the entire structure. - * - * During resume we also only need to use one swap_map_page structure - * at a time. - */ - -#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(long) - 1) - -struct swap_map_page { - unsigned long entries[MAP_PAGE_ENTRIES]; - unsigned long next_swap; -}; - -/** - * The swap_map_handle structure is used for handling swap in - * a file-alike way - */ - -struct swap_map_handle { - struct swap_map_page *cur; - unsigned long cur_swap; - struct bitmap_page *bitmap; - unsigned int k; -}; - -static void release_swap_writer(struct swap_map_handle *handle) -{ - if (handle->cur) - free_page((unsigned long)handle->cur); - handle->cur = NULL; - if (handle->bitmap) - free_bitmap(handle->bitmap); - handle->bitmap = NULL; -} - -static int get_swap_writer(struct swap_map_handle *handle) -{ - handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL); - if (!handle->cur) - return -ENOMEM; - handle->bitmap = alloc_bitmap(count_swap_pages(root_swap, 0)); - if (!handle->bitmap) { - release_swap_writer(handle); - return -ENOMEM; - } - handle->cur_swap = alloc_swap_page(root_swap, handle->bitmap); - if (!handle->cur_swap) { - release_swap_writer(handle); - return -ENOSPC; - } - handle->k = 0; - return 0; -} - -static int swap_write_page(struct swap_map_handle *handle, void *buf) -{ - int error; - unsigned long offset; - - if (!handle->cur) - return -EINVAL; - offset = alloc_swap_page(root_swap, handle->bitmap); - error = write_page(buf, offset); - if (error) - return error; - handle->cur->entries[handle->k++] = offset; - if (handle->k >= MAP_PAGE_ENTRIES) { - offset = alloc_swap_page(root_swap, handle->bitmap); - if (!offset) - return -ENOSPC; - handle->cur->next_swap = offset; - error = write_page(handle->cur, handle->cur_swap); - if (error) - return error; - memset(handle->cur, 0, PAGE_SIZE); - handle->cur_swap = offset; - handle->k = 0; - } - return 0; -} - -static int flush_swap_writer(struct swap_map_handle *handle) -{ - if (handle->cur && handle->cur_swap) - return write_page(handle->cur, handle->cur_swap); - else - return -EINVAL; -} - -/** - * save_image - save the suspend image data - */ - -static int save_image(struct swap_map_handle *handle, - struct snapshot_handle *snapshot, - unsigned int nr_pages) -{ - unsigned int m; - int ret; - int error = 0; - - printk("Saving image data pages (%u pages) ... ", nr_pages); - m = nr_pages / 100; - if (!m) - m = 1; - nr_pages = 0; - do { - ret = snapshot_read_next(snapshot, PAGE_SIZE); - if (ret > 0) { - error = swap_write_page(handle, data_of(*snapshot)); - if (error) - break; - if (!(nr_pages % m)) - printk("\b\b\b\b%3d%%", nr_pages / m); - nr_pages++; - } - } while (ret > 0); - if (!error) - printk("\b\b\b\bdone\n"); - return error; -} - -/** - * enough_swap - Make sure we have enough swap to save the image. - * - * Returns TRUE or FALSE after checking the total amount of swap - * space avaiable from the resume partition. - */ - -static int enough_swap(unsigned int nr_pages) -{ - unsigned int free_swap = count_swap_pages(root_swap, 1); - - pr_debug("swsusp: free swap pages: %u\n", free_swap); - return free_swap > (nr_pages + PAGES_FOR_IO + - (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE); -} - -/** - * swsusp_write - Write entire image and metadata. - * - * It is important _NOT_ to umount filesystems at this point. We want - * them synced (in case something goes wrong) but we DO not want to mark - * filesystem clean: it is not. (And it does not matter, if we resume - * correctly, we'll mark system clean, anyway.) - */ - -int swsusp_write(void) -{ - struct swap_map_handle handle; - struct snapshot_handle snapshot; - struct swsusp_info *header; - unsigned long start; - int error; - - if ((error = swsusp_swap_check())) { - printk(KERN_ERR "swsusp: Cannot find swap device, try swapon -a.\n"); - return error; - } - memset(&snapshot, 0, sizeof(struct snapshot_handle)); - error = snapshot_read_next(&snapshot, PAGE_SIZE); - if (error < PAGE_SIZE) - return error < 0 ? error : -EFAULT; - header = (struct swsusp_info *)data_of(snapshot); - if (!enough_swap(header->pages)) { - printk(KERN_ERR "swsusp: Not enough free swap\n"); - return -ENOSPC; - } - error = get_swap_writer(&handle); - if (!error) { - start = handle.cur_swap; - error = swap_write_page(&handle, header); - } - if (!error) - error = save_image(&handle, &snapshot, header->pages - 1); - if (!error) { - flush_swap_writer(&handle); - printk("S"); - error = mark_swapfiles(swp_entry(root_swap, start)); - printk("|\n"); - } - if (error) - free_all_swap_pages(root_swap, handle.bitmap); - release_swap_writer(&handle); - return error; -} - /** * swsusp_shrink_memory - Try to free as much memory as needed * @@ -578,252 +271,3 @@ int swsusp_resume(void) local_irq_enable(); return error; } - -/* - * Using bio to read from swap. - * This code requires a bit more work than just using buffer heads - * but, it is the recommended way for 2.5/2.6. - * The following are to signal the beginning and end of I/O. Bios - * finish asynchronously, while we want them to happen synchronously. - * A simple atomic_t, and a wait loop take care of this problem. - */ - -static atomic_t io_done = ATOMIC_INIT(0); - -static int end_io(struct bio *bio, unsigned int num, int err) -{ - if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) - panic("I/O error reading memory image"); - atomic_set(&io_done, 0); - return 0; -} - -static struct block_device *resume_bdev; - -/** - * submit - submit BIO request. - * @rw: READ or WRITE. - * @off physical offset of page. - * @page: page we're reading or writing. - * - * Straight from the textbook - allocate and initialize the bio. - * If we're writing, make sure the page is marked as dirty. - * Then submit it and wait. - */ - -static int submit(int rw, pgoff_t page_off, void *page) -{ - int error = 0; - struct bio *bio; - - bio = bio_alloc(GFP_ATOMIC, 1); - if (!bio) - return -ENOMEM; - bio->bi_sector = page_off * (PAGE_SIZE >> 9); - bio->bi_bdev = resume_bdev; - bio->bi_end_io = end_io; - - if (bio_add_page(bio, virt_to_page(page), PAGE_SIZE, 0) < PAGE_SIZE) { - printk("swsusp: ERROR: adding page to bio at %ld\n",page_off); - error = -EFAULT; - goto Done; - } - - - atomic_set(&io_done, 1); - submit_bio(rw | (1 << BIO_RW_SYNC), bio); - while (atomic_read(&io_done)) - yield(); - if (rw == READ) - bio_set_pages_dirty(bio); - Done: - bio_put(bio); - return error; -} - -static int bio_read_page(pgoff_t page_off, void *page) -{ - return submit(READ, page_off, page); -} - -static int bio_write_page(pgoff_t page_off, void *page) -{ - return submit(WRITE, page_off, page); -} - -/** - * The following functions allow us to read data using a swap map - * in a file-alike way - */ - -static void release_swap_reader(struct swap_map_handle *handle) -{ - if (handle->cur) - free_page((unsigned long)handle->cur); - handle->cur = NULL; -} - -static int get_swap_reader(struct swap_map_handle *handle, - swp_entry_t start) -{ - int error; - - if (!swp_offset(start)) - return -EINVAL; - handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC); - if (!handle->cur) - return -ENOMEM; - error = bio_read_page(swp_offset(start), handle->cur); - if (error) { - release_swap_reader(handle); - return error; - } - handle->k = 0; - return 0; -} - -static int swap_read_page(struct swap_map_handle *handle, void *buf) -{ - unsigned long offset; - int error; - - if (!handle->cur) - return -EINVAL; - offset = handle->cur->entries[handle->k]; - if (!offset) - return -EFAULT; - error = bio_read_page(offset, buf); - if (error) - return error; - if (++handle->k >= MAP_PAGE_ENTRIES) { - handle->k = 0; - offset = handle->cur->next_swap; - if (!offset) - release_swap_reader(handle); - else - error = bio_read_page(offset, handle->cur); - } - return error; -} - -/** - * load_image - load the image using the swap map handle - * @handle and the snapshot handle @snapshot - * (assume there are @nr_pages pages to load) - */ - -static int load_image(struct swap_map_handle *handle, - struct snapshot_handle *snapshot, - unsigned int nr_pages) -{ - unsigned int m; - int ret; - int error = 0; - - printk("Loading image data pages (%u pages) ... ", nr_pages); - m = nr_pages / 100; - if (!m) - m = 1; - nr_pages = 0; - do { - ret = snapshot_write_next(snapshot, PAGE_SIZE); - if (ret > 0) { - error = swap_read_page(handle, data_of(*snapshot)); - if (error) - break; - if (!(nr_pages % m)) - printk("\b\b\b\b%3d%%", nr_pages / m); - nr_pages++; - } - } while (ret > 0); - if (!error) - printk("\b\b\b\bdone\n"); - if (!snapshot_image_loaded(snapshot)) - error = -ENODATA; - return error; -} - -int swsusp_read(void) -{ - int error; - struct swap_map_handle handle; - struct snapshot_handle snapshot; - struct swsusp_info *header; - unsigned int nr_pages; - - if (IS_ERR(resume_bdev)) { - pr_debug("swsusp: block device not initialised\n"); - return PTR_ERR(resume_bdev); - } - - memset(&snapshot, 0, sizeof(struct snapshot_handle)); - error = snapshot_write_next(&snapshot, PAGE_SIZE); - if (error < PAGE_SIZE) - return error < 0 ? error : -EFAULT; - header = (struct swsusp_info *)data_of(snapshot); - error = get_swap_reader(&handle, swsusp_header.image); - if (!error) - error = swap_read_page(&handle, header); - if (!error) { - nr_pages = header->image_pages; - error = load_image(&handle, &snapshot, nr_pages); - } - release_swap_reader(&handle); - - blkdev_put(resume_bdev); - - if (!error) - pr_debug("swsusp: Reading resume file was successful\n"); - else - pr_debug("swsusp: Error %d resuming\n", error); - return error; -} - -/** - * swsusp_check - Check for swsusp signature in the resume device - */ - -int swsusp_check(void) -{ - int error; - - resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ); - if (!IS_ERR(resume_bdev)) { - set_blocksize(resume_bdev, PAGE_SIZE); - memset(&swsusp_header, 0, sizeof(swsusp_header)); - if ((error = bio_read_page(0, &swsusp_header))) - return error; - if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) { - memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10); - /* Reset swap signature now */ - error = bio_write_page(0, &swsusp_header); - } else { - return -EINVAL; - } - if (error) - blkdev_put(resume_bdev); - else - pr_debug("swsusp: Signature found, resuming\n"); - } else { - error = PTR_ERR(resume_bdev); - } - - if (error) - pr_debug("swsusp: Error %d check for resume file\n", error); - - return error; -} - -/** - * swsusp_close - close swap device. - */ - -void swsusp_close(void) -{ - if (IS_ERR(resume_bdev)) { - pr_debug("swsusp: block device not initialised\n"); - return; - } - - blkdev_put(resume_bdev); -} -- cgit v1.2.3-70-g09d2