diff options
Diffstat (limited to 'kernel/power/swap.c')
| -rw-r--r-- | kernel/power/swap.c | 256 |
1 files changed, 146 insertions, 110 deletions
diff --git a/kernel/power/swap.c b/kernel/power/swap.c index 70ae21f7370d..33a186373bef 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -46,19 +46,18 @@ static bool clean_pages_on_read; static bool clean_pages_on_decompress; /* - * 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_ENTRIES swap entries. - * These structures are stored on the swap and linked together with the - * help of the .next_swap member. + * 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_ENTRIES 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. + * 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 pick up all swap_map_page structures into a list. + * During resume we pick up all swap_map_page structures into a list. */ - #define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1) /* @@ -89,10 +88,8 @@ struct swap_map_page_list { }; /* - * The swap_map_handle structure is used for handling swap in - * a file-alike way + * The swap_map_handle structure is used for handling swap in a file-alike way. */ - struct swap_map_handle { struct swap_map_page *cur; struct swap_map_page_list *maps; @@ -117,10 +114,9 @@ struct swsusp_header { static struct swsusp_header *swsusp_header; /* - * The following functions are used for tracing the allocated - * swap pages, so that they can be freed in case of an error. + * The following functions are used for tracing the allocated swap pages, so + * that they can be freed in case of an error. */ - struct swsusp_extent { struct rb_node node; unsigned long start; @@ -170,15 +166,14 @@ static int swsusp_extents_insert(unsigned long swap_offset) return 0; } -/* - * alloc_swapdev_block - allocate a swap page and register that it has - * been allocated, so that it can be freed in case of an error. - */ - sector_t alloc_swapdev_block(int swap) { unsigned long offset; + /* + * Allocate a swap page and register that it has been allocated, so that + * it can be freed in case of an error. + */ offset = swp_offset(get_swap_page_of_type(swap)); if (offset) { if (swsusp_extents_insert(offset)) @@ -189,16 +184,14 @@ sector_t alloc_swapdev_block(int swap) return 0; } -/* - * free_all_swap_pages - free swap pages allocated for saving image data. - * It also frees the extents used to register which swap entries had been - * allocated. - */ - void free_all_swap_pages(int swap) { struct rb_node *node; + /* + * Free swap pages allocated for saving image data. It also frees the + * extents used to register which swap entries had been allocated. + */ while ((node = swsusp_extents.rb_node)) { struct swsusp_extent *ext; @@ -303,6 +296,7 @@ static int hib_wait_io(struct hib_bio_batch *hb) /* * Saving part */ + static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags) { int error; @@ -336,16 +330,14 @@ static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags) */ unsigned int swsusp_header_flags; -/** - * swsusp_swap_check - check if the resume device is a swap device - * and get its index (if so) - * - * This is called before saving image - */ static int swsusp_swap_check(void) { int res; + /* + * Check if the resume device is a swap device and get its index (if so). + * This is called before saving the image. + */ if (swsusp_resume_device) res = swap_type_of(swsusp_resume_device, swsusp_resume_block); else @@ -362,13 +354,6 @@ static int swsusp_swap_check(void) return 0; } -/** - * write_page - Write one page to given swap location. - * @buf: Address we're writing. - * @offset: Offset of the swap page we're writing to. - * @hb: bio completion batch - */ - static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb) { gfp_t gfp = GFP_NOIO | __GFP_NOWARN | __GFP_NORETRY; @@ -519,17 +504,14 @@ static int swap_writer_finish(struct swap_map_handle *handle, CMP_HEADER, PAGE_SIZE) #define CMP_SIZE (CMP_PAGES * PAGE_SIZE) -/* Maximum number of threads for compression/decompression. */ -#define CMP_THREADS 3 +/* Default number of threads for compression/decompression. */ +#define CMP_THREADS 3 +static unsigned int hibernate_compression_threads = CMP_THREADS; /* Minimum/maximum number of pages for read buffering. */ #define CMP_MIN_RD_PAGES 1024 #define CMP_MAX_RD_PAGES 8192 -/** - * save_image - save the suspend image data - */ - static int save_image(struct swap_map_handle *handle, struct snapshot_handle *snapshot, unsigned int nr_to_write) @@ -585,13 +567,48 @@ struct crc_data { wait_queue_head_t go; /* start crc update */ wait_queue_head_t done; /* crc update done */ u32 *crc32; /* points to handle's crc32 */ - size_t *unc_len[CMP_THREADS]; /* uncompressed lengths */ - unsigned char *unc[CMP_THREADS]; /* uncompressed data */ + size_t **unc_len; /* uncompressed lengths */ + unsigned char **unc; /* uncompressed data */ }; -/* - * CRC32 update function that runs in its own thread. - */ +static struct crc_data *alloc_crc_data(int nr_threads) +{ + struct crc_data *crc; + + crc = kzalloc(sizeof(*crc), GFP_KERNEL); + if (!crc) + return NULL; + + crc->unc = kcalloc(nr_threads, sizeof(*crc->unc), GFP_KERNEL); + if (!crc->unc) + goto err_free_crc; + + crc->unc_len = kcalloc(nr_threads, sizeof(*crc->unc_len), GFP_KERNEL); + if (!crc->unc_len) + goto err_free_unc; + + return crc; + +err_free_unc: + kfree(crc->unc); +err_free_crc: + kfree(crc); + return NULL; +} + +static void free_crc_data(struct crc_data *crc) +{ + if (!crc) + return; + + if (crc->thr) + kthread_stop(crc->thr); + + kfree(crc->unc_len); + kfree(crc->unc); + kfree(crc); +} + static int crc32_threadfn(void *data) { struct crc_data *d = data; @@ -616,6 +633,7 @@ static int crc32_threadfn(void *data) } return 0; } + /* * Structure used for data compression. */ @@ -637,9 +655,6 @@ struct cmp_data { /* Indicates the image size after compression */ static atomic64_t compressed_size = ATOMIC_INIT(0); -/* - * Compression function that runs in its own thread. - */ static int compress_threadfn(void *data) { struct cmp_data *d = data; @@ -671,12 +686,6 @@ static int compress_threadfn(void *data) return 0; } -/** - * save_compressed_image - Save the suspend image data after compression. - * @handle: Swap map handle to use for saving the image. - * @snapshot: Image to read data from. - * @nr_to_write: Number of pages to save. - */ static int save_compressed_image(struct swap_map_handle *handle, struct snapshot_handle *snapshot, unsigned int nr_to_write) @@ -703,7 +712,7 @@ static int save_compressed_image(struct swap_map_handle *handle, * footprint. */ nr_threads = num_online_cpus() - 1; - nr_threads = clamp_val(nr_threads, 1, CMP_THREADS); + nr_threads = clamp_val(nr_threads, 1, hibernate_compression_threads); page = (void *)__get_free_page(GFP_NOIO | __GFP_HIGH); if (!page) { @@ -719,7 +728,7 @@ static int save_compressed_image(struct swap_map_handle *handle, goto out_clean; } - crc = kzalloc(sizeof(*crc), GFP_KERNEL); + crc = alloc_crc_data(nr_threads); if (!crc) { pr_err("Failed to allocate crc\n"); ret = -ENOMEM; @@ -888,11 +897,7 @@ out_finish: out_clean: hib_finish_batch(&hb); - if (crc) { - if (crc->thr) - kthread_stop(crc->thr); - kfree(crc); - } + free_crc_data(crc); if (data) { for (thr = 0; thr < nr_threads; thr++) { if (data[thr].thr) @@ -908,13 +913,6 @@ out_clean: return ret; } -/** - * enough_swap - Make sure we have enough swap to save the image. - * - * Returns TRUE or FALSE after checking the total amount of swap - * space available from the resume partition. - */ - static int enough_swap(unsigned int nr_pages) { unsigned int free_swap = count_swap_pages(root_swap, 1); @@ -927,15 +925,16 @@ static int enough_swap(unsigned int nr_pages) } /** - * swsusp_write - Write entire image and metadata. - * @flags: flags to pass to the "boot" kernel in the image header + * swsusp_write - Write entire image and metadata. + * @flags: flags to pass to the "boot" kernel in the image header + * + * 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.) * - * 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.) + * Return: 0 on success, negative error code on failure. */ - int swsusp_write(unsigned int flags) { struct swap_map_handle handle; @@ -978,8 +977,8 @@ out_finish: } /* - * The following functions allow us to read data using a swap map - * in a file-like way. + * The following functions allow us to read data using a swap map in a file-like + * way. */ static void release_swap_reader(struct swap_map_handle *handle) @@ -1081,12 +1080,6 @@ static int swap_reader_finish(struct swap_map_handle *handle) return 0; } -/** - * 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_to_read) @@ -1157,9 +1150,6 @@ struct dec_data { unsigned char cmp[CMP_SIZE]; /* compressed buffer */ }; -/* - * Decompression function that runs in its own thread. - */ static int decompress_threadfn(void *data) { struct dec_data *d = data; @@ -1194,12 +1184,6 @@ static int decompress_threadfn(void *data) return 0; } -/** - * load_compressed_image - Load compressed image data and decompress it. - * @handle: Swap map handle to use for loading data. - * @snapshot: Image to copy uncompressed data into. - * @nr_to_read: Number of pages to load. - */ static int load_compressed_image(struct swap_map_handle *handle, struct snapshot_handle *snapshot, unsigned int nr_to_read) @@ -1227,7 +1211,7 @@ static int load_compressed_image(struct swap_map_handle *handle, * footprint. */ nr_threads = num_online_cpus() - 1; - nr_threads = clamp_val(nr_threads, 1, CMP_THREADS); + nr_threads = clamp_val(nr_threads, 1, hibernate_compression_threads); page = vmalloc_array(CMP_MAX_RD_PAGES, sizeof(*page)); if (!page) { @@ -1243,7 +1227,7 @@ static int load_compressed_image(struct swap_map_handle *handle, goto out_clean; } - crc = kzalloc(sizeof(*crc), GFP_KERNEL); + crc = alloc_crc_data(nr_threads); if (!crc) { pr_err("Failed to allocate crc\n"); ret = -ENOMEM; @@ -1510,11 +1494,7 @@ out_clean: hib_finish_batch(&hb); for (i = 0; i < ring_size; i++) free_page((unsigned long)page[i]); - if (crc) { - if (crc->thr) - kthread_stop(crc->thr); - kfree(crc); - } + free_crc_data(crc); if (data) { for (thr = 0; thr < nr_threads; thr++) { if (data[thr].thr) @@ -1533,8 +1513,9 @@ out_clean: * swsusp_read - read the hibernation image. * @flags_p: flags passed by the "frozen" kernel in the image header should * be written into this memory location + * + * Return: 0 on success, negative error code on failure. */ - int swsusp_read(unsigned int *flags_p) { int error; @@ -1571,8 +1552,9 @@ static void *swsusp_holder; /** * swsusp_check - Open the resume device and check for the swsusp signature. * @exclusive: Open the resume device exclusively. + * + * Return: 0 if a valid image is found, negative error code otherwise. */ - int swsusp_check(bool exclusive) { void *holder = exclusive ? &swsusp_holder : NULL; @@ -1622,7 +1604,6 @@ put: /** * swsusp_close - close resume device. */ - void swsusp_close(void) { if (IS_ERR(hib_resume_bdev_file)) { @@ -1634,9 +1615,10 @@ void swsusp_close(void) } /** - * swsusp_unmark - Unmark swsusp signature in the resume device + * swsusp_unmark - Unmark swsusp signature in the resume device + * + * Return: 0 on success, negative error code on failure. */ - #ifdef CONFIG_SUSPEND int swsusp_unmark(void) { @@ -1662,8 +1644,46 @@ int swsusp_unmark(void) } #endif +static ssize_t hibernate_compression_threads_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + return sysfs_emit(buf, "%d\n", hibernate_compression_threads); +} + +static ssize_t hibernate_compression_threads_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t n) +{ + unsigned long val; + + if (kstrtoul(buf, 0, &val)) + return -EINVAL; + + if (val < 1) + return -EINVAL; + + hibernate_compression_threads = val; + return n; +} +power_attr(hibernate_compression_threads); + +static struct attribute *g[] = { + &hibernate_compression_threads_attr.attr, + NULL, +}; + +static const struct attribute_group attr_group = { + .attrs = g, +}; + static int __init swsusp_header_init(void) { + int error; + + error = sysfs_create_group(power_kobj, &attr_group); + if (error) + return -ENOMEM; + swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL); if (!swsusp_header) panic("Could not allocate memory for swsusp_header\n"); @@ -1671,3 +1691,19 @@ static int __init swsusp_header_init(void) } core_initcall(swsusp_header_init); + +static int __init hibernate_compression_threads_setup(char *str) +{ + int rc = kstrtouint(str, 0, &hibernate_compression_threads); + + if (rc) + return rc; + + if (hibernate_compression_threads < 1) + hibernate_compression_threads = CMP_THREADS; + + return 1; + +} + +__setup("hibernate_compression_threads=", hibernate_compression_threads_setup); |