diff options
Diffstat (limited to 'kernel/power/tuxonice_bio_signature.c')
| -rw-r--r-- | kernel/power/tuxonice_bio_signature.c | 403 |
1 files changed, 403 insertions, 0 deletions
diff --git a/kernel/power/tuxonice_bio_signature.c b/kernel/power/tuxonice_bio_signature.c new file mode 100644 index 000000000..f5418f092 --- /dev/null +++ b/kernel/power/tuxonice_bio_signature.c @@ -0,0 +1,403 @@ +/* + * kernel/power/tuxonice_bio_signature.c + * + * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au) + * + * Distributed under GPLv2. + * + */ + +#include <linux/fs_uuid.h> + +#include "tuxonice.h" +#include "tuxonice_sysfs.h" +#include "tuxonice_modules.h" +#include "tuxonice_prepare_image.h" +#include "tuxonice_bio.h" +#include "tuxonice_ui.h" +#include "tuxonice_alloc.h" +#include "tuxonice_io.h" +#include "tuxonice_builtin.h" +#include "tuxonice_bio_internal.h" + +struct sig_data *toi_sig_data; + +/* Struct of swap header pages */ + +struct old_sig_data { + dev_t device; + unsigned long sector; + int resume_attempted; + int orig_sig_type; +}; + +union diskpage { + union swap_header swh; /* swh.magic is the only member used */ + struct sig_data sig_data; + struct old_sig_data old_sig_data; +}; + +union p_diskpage { + union diskpage *pointer; + char *ptr; + unsigned long address; +}; + +char *toi_cur_sig_page; +char *toi_orig_sig_page; +int have_image; +int have_old_image; + +int get_signature_page(void) +{ + if (!toi_cur_sig_page) { + toi_message(TOI_IO, TOI_VERBOSE, 0, + "Allocating current signature page."); + toi_cur_sig_page = (char *) toi_get_zeroed_page(38, + TOI_ATOMIC_GFP); + if (!toi_cur_sig_page) { + printk(KERN_ERR "Failed to allocate memory for the " + "current image signature.\n"); + return -ENOMEM; + } + + toi_sig_data = (struct sig_data *) toi_cur_sig_page; + } + + toi_message(TOI_IO, TOI_VERBOSE, 0, "Reading signature from dev %lx," + " sector %d.", + resume_block_device->bd_dev, resume_firstblock); + + return toi_bio_ops.bdev_page_io(READ, resume_block_device, + resume_firstblock, virt_to_page(toi_cur_sig_page)); +} + +void forget_signature_page(void) +{ + if (toi_cur_sig_page) { + toi_sig_data = NULL; + toi_message(TOI_IO, TOI_VERBOSE, 0, "Freeing toi_cur_sig_page" + " (%p).", toi_cur_sig_page); + toi_free_page(38, (unsigned long) toi_cur_sig_page); + toi_cur_sig_page = NULL; + } + + if (toi_orig_sig_page) { + toi_message(TOI_IO, TOI_VERBOSE, 0, "Freeing toi_orig_sig_page" + " (%p).", toi_orig_sig_page); + toi_free_page(38, (unsigned long) toi_orig_sig_page); + toi_orig_sig_page = NULL; + } +} + +/* + * We need to ensure we use the signature page that's currently on disk, + * so as to not remove the image header. Post-atomic-restore, the orig sig + * page will be empty, so we can use that as our method of knowing that we + * need to load the on-disk signature and not use the non-image sig in + * memory. (We're going to powerdown after writing the change, so it's safe. + */ +int toi_bio_mark_resume_attempted(int flag) +{ + toi_message(TOI_IO, TOI_VERBOSE, 0, "Make resume attempted = %d.", + flag); + if (!toi_orig_sig_page) { + forget_signature_page(); + get_signature_page(); + } + toi_sig_data->resumed_before = flag; + return toi_bio_ops.bdev_page_io(WRITE, resume_block_device, + resume_firstblock, virt_to_page(toi_cur_sig_page)); +} + +int toi_bio_mark_have_image(void) +{ + int result = 0; + char buf[32]; + struct fs_info *fs_info; + + toi_message(TOI_IO, TOI_VERBOSE, 0, "Recording that an image exists."); + memcpy(toi_sig_data->sig, tuxonice_signature, + sizeof(tuxonice_signature)); + toi_sig_data->have_image = 1; + toi_sig_data->resumed_before = 0; + toi_sig_data->header_dev_t = get_header_dev_t(); + toi_sig_data->have_uuid = 0; + + fs_info = fs_info_from_block_dev(get_header_bdev()); + if (fs_info && !IS_ERR(fs_info)) { + memcpy(toi_sig_data->header_uuid, &fs_info->uuid, 16); + free_fs_info(fs_info); + } else + result = (int) PTR_ERR(fs_info); + + if (!result) { + toi_message(TOI_IO, TOI_VERBOSE, 0, "Got uuid for dev_t %s.", + format_dev_t(buf, get_header_dev_t())); + toi_sig_data->have_uuid = 1; + } else + toi_message(TOI_IO, TOI_VERBOSE, 0, "Could not get uuid for " + "dev_t %s.", + format_dev_t(buf, get_header_dev_t())); + + toi_sig_data->first_header_block = get_headerblock(); + have_image = 1; + toi_message(TOI_IO, TOI_VERBOSE, 0, "header dev_t is %x. First block " + "is %d.", toi_sig_data->header_dev_t, + toi_sig_data->first_header_block); + + memcpy(toi_sig_data->sig2, tuxonice_signature, + sizeof(tuxonice_signature)); + toi_sig_data->header_version = TOI_HEADER_VERSION; + + return toi_bio_ops.bdev_page_io(WRITE, resume_block_device, + resume_firstblock, virt_to_page(toi_cur_sig_page)); +} + +int remove_old_signature(void) +{ + union p_diskpage swap_header_page = (union p_diskpage) toi_cur_sig_page; + char *orig_sig; + char *header_start = (char *) toi_get_zeroed_page(38, TOI_ATOMIC_GFP); + int result; + struct block_device *header_bdev; + struct old_sig_data *old_sig_data = + &swap_header_page.pointer->old_sig_data; + + header_bdev = toi_open_bdev(NULL, old_sig_data->device, 1); + result = toi_bio_ops.bdev_page_io(READ, header_bdev, + old_sig_data->sector, virt_to_page(header_start)); + + if (result) + goto out; + + /* + * TODO: Get the original contents of the first bytes of the swap + * header page. + */ + if (!old_sig_data->orig_sig_type) + orig_sig = "SWAP-SPACE"; + else + orig_sig = "SWAPSPACE2"; + + memcpy(swap_header_page.pointer->swh.magic.magic, orig_sig, 10); + memcpy(swap_header_page.ptr, header_start, 10); + + result = toi_bio_ops.bdev_page_io(WRITE, resume_block_device, + resume_firstblock, virt_to_page(swap_header_page.ptr)); + +out: + toi_close_bdev(header_bdev); + have_old_image = 0; + toi_free_page(38, (unsigned long) header_start); + return result; +} + +/* + * toi_bio_restore_original_signature - restore the original signature + * + * At boot time (aborting pre atomic-restore), toi_orig_sig_page gets used. + * It will have the original signature page contents, stored in the image + * header. Post atomic-restore, we use :toi_cur_sig_page, which will contain + * the contents that were loaded when we started the cycle. + */ +int toi_bio_restore_original_signature(void) +{ + char *use = toi_orig_sig_page ? toi_orig_sig_page : toi_cur_sig_page; + + if (have_old_image) + return remove_old_signature(); + + if (!use) { + printk("toi_bio_restore_original_signature: No signature " + "page loaded.\n"); + return 0; + } + + toi_message(TOI_IO, TOI_VERBOSE, 0, "Recording that no image exists."); + have_image = 0; + toi_sig_data->have_image = 0; + return toi_bio_ops.bdev_page_io(WRITE, resume_block_device, + resume_firstblock, virt_to_page(use)); +} + +/* + * check_for_signature - See whether we have an image. + * + * Returns 0 if no image, 1 if there is one, -1 if indeterminate. + */ +int toi_check_for_signature(void) +{ + union p_diskpage swap_header_page; + int type; + const char *normal_sigs[] = {"SWAP-SPACE", "SWAPSPACE2" }; + const char *swsusp_sigs[] = {"S1SUSP", "S2SUSP", "S1SUSPEND" }; + char *swap_header; + + if (!toi_cur_sig_page) { + int result = get_signature_page(); + + if (result) + return result; + } + + /* + * Start by looking for the binary header. + */ + if (!memcmp(tuxonice_signature, toi_cur_sig_page, + sizeof(tuxonice_signature))) { + have_image = toi_sig_data->have_image; + toi_message(TOI_IO, TOI_VERBOSE, 0, "Have binary signature. " + "Have image is %d.", have_image); + if (have_image) + toi_message(TOI_IO, TOI_VERBOSE, 0, "header dev_t is " + "%x. First block is %d.", + toi_sig_data->header_dev_t, + toi_sig_data->first_header_block); + return toi_sig_data->have_image; + } + + /* + * Failing that, try old file allocator headers. + */ + + if (!memcmp(HaveImage, toi_cur_sig_page, strlen(HaveImage))) { + have_image = 1; + return 1; + } + + have_image = 0; + + if (!memcmp(NoImage, toi_cur_sig_page, strlen(NoImage))) + return 0; + + /* + * Nope? How about swap? + */ + swap_header_page = (union p_diskpage) toi_cur_sig_page; + swap_header = swap_header_page.pointer->swh.magic.magic; + + /* Normal swapspace? */ + for (type = 0; type < 2; type++) + if (!memcmp(normal_sigs[type], swap_header, + strlen(normal_sigs[type]))) + return 0; + + /* Swsusp or uswsusp? */ + for (type = 0; type < 3; type++) + if (!memcmp(swsusp_sigs[type], swap_header, + strlen(swsusp_sigs[type]))) + return 2; + + /* Old TuxOnIce version? */ + if (!memcmp(tuxonice_signature, swap_header, + sizeof(tuxonice_signature) - 1)) { + toi_message(TOI_IO, TOI_VERBOSE, 0, "Found old TuxOnIce " + "signature."); + have_old_image = 1; + return 3; + } + + return -1; +} + +/* + * Image_exists + * + * Returns -1 if don't know, otherwise 0 (no) or 1 (yes). + */ +int toi_bio_image_exists(int quiet) +{ + int result; + char *msg = NULL; + + toi_message(TOI_IO, TOI_VERBOSE, 0, "toi_bio_image_exists."); + + if (!resume_dev_t) { + if (!quiet) + printk(KERN_INFO "Not even trying to read header " + "because resume_dev_t is not set.\n"); + return -1; + } + + if (open_resume_dev_t(0, quiet)) + return -1; + + result = toi_check_for_signature(); + + clear_toi_state(TOI_RESUMED_BEFORE); + if (toi_sig_data->resumed_before) + set_toi_state(TOI_RESUMED_BEFORE); + + if (quiet || result == -ENOMEM) + return result; + + if (result == -1) + msg = "TuxOnIce: Unable to find a signature." + " Could you have moved a swap file?\n"; + else if (!result) + msg = "TuxOnIce: No image found.\n"; + else if (result == 1) + msg = "TuxOnIce: Image found.\n"; + else if (result == 2) + msg = "TuxOnIce: uswsusp or swsusp image found.\n"; + else if (result == 3) + msg = "TuxOnIce: Old implementation's signature found.\n"; + + printk(KERN_INFO "%s", msg); + + return result; +} + +int toi_bio_scan_for_image(int quiet) +{ + struct block_device *bdev; + char default_name[255] = ""; + + if (!quiet) + printk(KERN_DEBUG "Scanning swap devices for TuxOnIce " + "signature...\n"); + for (bdev = next_bdev_of_type(NULL, "swap"); bdev; + bdev = next_bdev_of_type(bdev, "swap")) { + int result; + char name[255] = ""; + sprintf(name, "%u:%u", MAJOR(bdev->bd_dev), + MINOR(bdev->bd_dev)); + if (!quiet) + printk(KERN_DEBUG "- Trying %s.\n", name); + resume_block_device = bdev; + resume_dev_t = bdev->bd_dev; + + result = toi_check_for_signature(); + + resume_block_device = NULL; + resume_dev_t = MKDEV(0, 0); + + if (!default_name[0]) + strcpy(default_name, name); + + if (result == 1) { + /* Got one! */ + strcpy(resume_file, name); + next_bdev_of_type(bdev, NULL); + if (!quiet) + printk(KERN_DEBUG " ==> Image found on %s.\n", + resume_file); + return 1; + } + forget_signature_page(); + } + + if (!quiet) + printk(KERN_DEBUG "TuxOnIce scan: No image found.\n"); + strcpy(resume_file, default_name); + return 0; +} + +int toi_bio_get_header_version(void) +{ + return (memcmp(toi_sig_data->sig2, tuxonice_signature, + sizeof(tuxonice_signature))) ? + 0 : toi_sig_data->header_version; + +} |