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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /kernel/power/tuxonice_bio_signature.c
Initial import
Diffstat (limited to 'kernel/power/tuxonice_bio_signature.c')
-rw-r--r--kernel/power/tuxonice_bio_signature.c403
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..ead874f8e
--- /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;
+
+}