/* * kernel/power/tuxonice_bio_signature.c * * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au) * * Distributed under GPLv2. * */ #include #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; }