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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_atomic_copy.c
Initial import
Diffstat (limited to 'kernel/power/tuxonice_atomic_copy.c')
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1 files changed, 469 insertions, 0 deletions
diff --git a/kernel/power/tuxonice_atomic_copy.c b/kernel/power/tuxonice_atomic_copy.c
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+/*
+ * kernel/power/tuxonice_atomic_copy.c
+ *
+ * Copyright 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ * Routines for doing the atomic save/restore.
+ */
+
+#include <linux/suspend.h>
+#include <linux/highmem.h>
+#include <linux/cpu.h>
+#include <linux/freezer.h>
+#include <linux/console.h>
+#include <linux/syscore_ops.h>
+#include <linux/ftrace.h>
+#include <asm/suspend.h>
+#include "tuxonice.h"
+#include "tuxonice_storage.h"
+#include "tuxonice_power_off.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_io.h"
+#include "tuxonice_prepare_image.h"
+#include "tuxonice_pageflags.h"
+#include "tuxonice_checksum.h"
+#include "tuxonice_builtin.h"
+#include "tuxonice_atomic_copy.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_modules.h"
+
+unsigned long extra_pd1_pages_used;
+
+/**
+ * free_pbe_list - free page backup entries used by the atomic copy code.
+ * @list: List to free.
+ * @highmem: Whether the list is in highmem.
+ *
+ * Normally, this function isn't used. If, however, we need to abort before
+ * doing the atomic copy, we use this to free the pbes previously allocated.
+ **/
+static void free_pbe_list(struct pbe **list, int highmem)
+{
+ while (*list) {
+ int i;
+ struct pbe *free_pbe, *next_page = NULL;
+ struct page *page;
+
+ if (highmem) {
+ page = (struct page *) *list;
+ free_pbe = (struct pbe *) kmap(page);
+ } else {
+ page = virt_to_page(*list);
+ free_pbe = *list;
+ }
+
+ for (i = 0; i < PBES_PER_PAGE; i++) {
+ if (!free_pbe)
+ break;
+ if (highmem)
+ toi__free_page(29, free_pbe->address);
+ else
+ toi_free_page(29,
+ (unsigned long) free_pbe->address);
+ free_pbe = free_pbe->next;
+ }
+
+ if (highmem) {
+ if (free_pbe)
+ next_page = free_pbe;
+ kunmap(page);
+ } else {
+ if (free_pbe)
+ next_page = free_pbe;
+ }
+
+ toi__free_page(29, page);
+ *list = (struct pbe *) next_page;
+ };
+}
+
+/**
+ * copyback_post - post atomic-restore actions
+ *
+ * After doing the atomic restore, we have a few more things to do:
+ * 1) We want to retain some values across the restore, so we now copy
+ * these from the nosave variables to the normal ones.
+ * 2) Set the status flags.
+ * 3) Resume devices.
+ * 4) Tell userui so it can redraw & restore settings.
+ * 5) Reread the page cache.
+ **/
+void copyback_post(void)
+{
+ struct toi_boot_kernel_data *bkd =
+ (struct toi_boot_kernel_data *) boot_kernel_data_buffer;
+
+ if (toi_activate_storage(1))
+ panic("Failed to reactivate our storage.");
+
+ toi_post_atomic_restore_modules(bkd);
+
+ toi_cond_pause(1, "About to reload secondary pagedir.");
+
+ if (read_pageset2(0))
+ panic("Unable to successfully reread the page cache.");
+
+ /*
+ * If the user wants to sleep again after resuming from full-off,
+ * it's most likely to be in order to suspend to ram, so we'll
+ * do this check after loading pageset2, to give them the fastest
+ * wakeup when they are ready to use the computer again.
+ */
+ toi_check_resleep();
+
+ if (test_action_state(TOI_INCREMENTAL_IMAGE))
+ toi_reset_dirtiness(1);
+}
+
+/**
+ * toi_copy_pageset1 - do the atomic copy of pageset1
+ *
+ * Make the atomic copy of pageset1. We can't use copy_page (as we once did)
+ * because we can't be sure what side effects it has. On my old Duron, with
+ * 3DNOW, kernel_fpu_begin increments preempt count, making our preempt
+ * count at resume time 4 instead of 3.
+ *
+ * We don't want to call kmap_atomic unconditionally because it has the side
+ * effect of incrementing the preempt count, which will leave it one too high
+ * post resume (the page containing the preempt count will be copied after
+ * its incremented. This is essentially the same problem.
+ **/
+void toi_copy_pageset1(void)
+{
+ int i;
+ unsigned long source_index, dest_index;
+
+ memory_bm_position_reset(pageset1_map);
+ memory_bm_position_reset(pageset1_copy_map);
+
+ source_index = memory_bm_next_pfn(pageset1_map, 0);
+ dest_index = memory_bm_next_pfn(pageset1_copy_map, 0);
+
+ for (i = 0; i < pagedir1.size; i++) {
+ unsigned long *origvirt, *copyvirt;
+ struct page *origpage, *copypage;
+ int loop = (PAGE_SIZE / sizeof(unsigned long)) - 1,
+ was_present1, was_present2;
+
+ origpage = pfn_to_page(source_index);
+ copypage = pfn_to_page(dest_index);
+
+ origvirt = PageHighMem(origpage) ?
+ kmap_atomic(origpage) :
+ page_address(origpage);
+
+ copyvirt = PageHighMem(copypage) ?
+ kmap_atomic(copypage) :
+ page_address(copypage);
+
+ was_present1 = kernel_page_present(origpage);
+ if (!was_present1)
+ kernel_map_pages(origpage, 1, 1);
+
+ was_present2 = kernel_page_present(copypage);
+ if (!was_present2)
+ kernel_map_pages(copypage, 1, 1);
+
+ while (loop >= 0) {
+ *(copyvirt + loop) = *(origvirt + loop);
+ loop--;
+ }
+
+ if (!was_present1)
+ kernel_map_pages(origpage, 1, 0);
+
+ if (!was_present2)
+ kernel_map_pages(copypage, 1, 0);
+
+ if (PageHighMem(origpage))
+ kunmap_atomic(origvirt);
+
+ if (PageHighMem(copypage))
+ kunmap_atomic(copyvirt);
+
+ source_index = memory_bm_next_pfn(pageset1_map, 0);
+ dest_index = memory_bm_next_pfn(pageset1_copy_map, 0);
+ }
+}
+
+/**
+ * __toi_post_context_save - steps after saving the cpu context
+ *
+ * Steps taken after saving the CPU state to make the actual
+ * atomic copy.
+ *
+ * Called from swsusp_save in snapshot.c via toi_post_context_save.
+ **/
+int __toi_post_context_save(void)
+{
+ unsigned long old_ps1_size = pagedir1.size;
+
+ check_checksums();
+
+ free_checksum_pages();
+
+ toi_recalculate_image_contents(1);
+
+ extra_pd1_pages_used = pagedir1.size > old_ps1_size ?
+ pagedir1.size - old_ps1_size : 0;
+
+ if (extra_pd1_pages_used > extra_pd1_pages_allowance) {
+ printk(KERN_INFO "Pageset1 has grown by %lu pages. "
+ "extra_pages_allowance is currently only %lu.\n",
+ pagedir1.size - old_ps1_size,
+ extra_pd1_pages_allowance);
+
+ /*
+ * Highlevel code will see this, clear the state and
+ * retry if we haven't already done so twice.
+ */
+ if (any_to_free(1)) {
+ set_abort_result(TOI_EXTRA_PAGES_ALLOW_TOO_SMALL);
+ return 1;
+ }
+ if (try_allocate_extra_memory()) {
+ printk(KERN_INFO "Failed to allocate the extra memory"
+ " needed. Restarting the process.");
+ set_abort_result(TOI_EXTRA_PAGES_ALLOW_TOO_SMALL);
+ return 1;
+ }
+ printk(KERN_INFO "However it looks like there's enough"
+ " free ram and storage to handle this, so "
+ " continuing anyway.");
+ /*
+ * What if try_allocate_extra_memory above calls
+ * toi_allocate_extra_pagedir_memory and it allocs a new
+ * slab page via toi_kzalloc which should be in ps1? So...
+ */
+ toi_recalculate_image_contents(1);
+ }
+
+ if (!test_action_state(TOI_TEST_FILTER_SPEED) &&
+ !test_action_state(TOI_TEST_BIO))
+ toi_copy_pageset1();
+
+ return 0;
+}
+
+/**
+ * toi_hibernate - high level code for doing the atomic copy
+ *
+ * High-level code which prepares to do the atomic copy. Loosely based
+ * on the swsusp version, but with the following twists:
+ * - We set toi_running so the swsusp code uses our code paths.
+ * - We give better feedback regarding what goes wrong if there is a
+ * problem.
+ * - We use an extra function to call the assembly, just in case this code
+ * is in a module (return address).
+ **/
+int toi_hibernate(void)
+{
+ int error;
+
+ error = toi_lowlevel_builtin();
+
+ if (!error) {
+ struct toi_boot_kernel_data *bkd =
+ (struct toi_boot_kernel_data *) boot_kernel_data_buffer;
+
+ /*
+ * The boot kernel's data may be larger (newer version) or
+ * smaller (older version) than ours. Copy the minimum
+ * of the two sizes, so that we don't overwrite valid values
+ * from pre-atomic copy.
+ */
+
+ memcpy(&toi_bkd, (char *) boot_kernel_data_buffer,
+ min_t(int, sizeof(struct toi_boot_kernel_data),
+ bkd->size));
+ }
+
+ return error;
+}
+
+/**
+ * toi_atomic_restore - prepare to do the atomic restore
+ *
+ * Get ready to do the atomic restore. This part gets us into the same
+ * state we are in prior to do calling do_toi_lowlevel while
+ * hibernating: hot-unplugging secondary cpus and freeze processes,
+ * before starting the thread that will do the restore.
+ **/
+int toi_atomic_restore(void)
+{
+ int error;
+
+ toi_prepare_status(DONT_CLEAR_BAR, "Atomic restore.");
+
+ memcpy(&toi_bkd.toi_nosave_commandline, saved_command_line,
+ strlen(saved_command_line));
+
+ toi_pre_atomic_restore_modules(&toi_bkd);
+
+ if (add_boot_kernel_data_pbe())
+ goto Failed;
+
+ toi_prepare_status(DONT_CLEAR_BAR, "Doing atomic copy/restore.");
+
+ if (toi_go_atomic(PMSG_QUIESCE, 0))
+ goto Failed;
+
+ /* We'll ignore saved state, but this gets preempt count (etc) right */
+ save_processor_state();
+
+ error = swsusp_arch_resume();
+ /*
+ * Code below is only ever reached in case of failure. Otherwise
+ * execution continues at place where swsusp_arch_suspend was called.
+ *
+ * We don't know whether it's safe to continue (this shouldn't happen),
+ * so lets err on the side of caution.
+ */
+ BUG();
+
+Failed:
+ free_pbe_list(&restore_pblist, 0);
+#ifdef CONFIG_HIGHMEM
+ free_pbe_list(&restore_highmem_pblist, 1);
+#endif
+ return 1;
+}
+
+/**
+ * toi_go_atomic - do the actual atomic copy/restore
+ * @state: The state to use for dpm_suspend_start & power_down calls.
+ * @suspend_time: Whether we're suspending or resuming.
+ **/
+int toi_go_atomic(pm_message_t state, int suspend_time)
+{
+ if (suspend_time) {
+ if (platform_begin(1)) {
+ set_abort_result(TOI_PLATFORM_PREP_FAILED);
+ toi_end_atomic(ATOMIC_STEP_PLATFORM_END, suspend_time, 3);
+ return 1;
+ }
+
+ if (dpm_prepare(PMSG_FREEZE)) {
+ set_abort_result(TOI_DPM_PREPARE_FAILED);
+ dpm_complete(PMSG_RECOVER);
+ toi_end_atomic(ATOMIC_STEP_PLATFORM_END, suspend_time, 3);
+ return 1;
+ }
+ }
+
+ suspend_console();
+ pm_restrict_gfp_mask();
+
+ if (suspend_time) {
+ if (dpm_suspend(state)) {
+ set_abort_result(TOI_DPM_SUSPEND_FAILED);
+ toi_end_atomic(ATOMIC_STEP_DEVICE_RESUME, suspend_time, 3);
+ return 1;
+ }
+ } else {
+ if (dpm_suspend_start(state)) {
+ set_abort_result(TOI_DPM_SUSPEND_FAILED);
+ toi_end_atomic(ATOMIC_STEP_DEVICE_RESUME, suspend_time, 3);
+ return 1;
+ }
+ }
+
+ /* At this point, dpm_suspend_start() has been called, but *not*
+ * dpm_suspend_noirq(). We *must* dpm_suspend_noirq() now.
+ * Otherwise, drivers for some devices (e.g. interrupt controllers)
+ * become desynchronized with the actual state of the hardware
+ * at resume time, and evil weirdness ensues.
+ */
+
+ if (dpm_suspend_end(state)) {
+ set_abort_result(TOI_DEVICE_REFUSED);
+ toi_end_atomic(ATOMIC_STEP_DEVICE_RESUME, suspend_time, 1);
+ return 1;
+ }
+
+ if (suspend_time) {
+ if (platform_pre_snapshot(1))
+ set_abort_result(TOI_PRE_SNAPSHOT_FAILED);
+ } else {
+ if (platform_pre_restore(1))
+ set_abort_result(TOI_PRE_RESTORE_FAILED);
+ }
+
+ if (test_result_state(TOI_ABORTED)) {
+ toi_end_atomic(ATOMIC_STEP_PLATFORM_FINISH, suspend_time, 1);
+ return 1;
+ }
+
+ if (disable_nonboot_cpus()) {
+ set_abort_result(TOI_CPU_HOTPLUG_FAILED);
+ toi_end_atomic(ATOMIC_STEP_CPU_HOTPLUG,
+ suspend_time, 1);
+ return 1;
+ }
+
+ local_irq_disable();
+
+ if (syscore_suspend()) {
+ set_abort_result(TOI_SYSCORE_REFUSED);
+ toi_end_atomic(ATOMIC_STEP_IRQS, suspend_time, 1);
+ return 1;
+ }
+
+ if (suspend_time && pm_wakeup_pending()) {
+ set_abort_result(TOI_WAKEUP_EVENT);
+ toi_end_atomic(ATOMIC_STEP_SYSCORE_RESUME, suspend_time, 1);
+ return 1;
+ }
+ return 0;
+}
+
+/**
+ * toi_end_atomic - post atomic copy/restore routines
+ * @stage: What step to start at.
+ * @suspend_time: Whether we're suspending or resuming.
+ * @error: Whether we're recovering from an error.
+ **/
+void toi_end_atomic(int stage, int suspend_time, int error)
+{
+ pm_message_t msg = suspend_time ? (error ? PMSG_RECOVER : PMSG_THAW) :
+ PMSG_RESTORE;
+
+ switch (stage) {
+ case ATOMIC_ALL_STEPS:
+ if (!suspend_time) {
+ events_check_enabled = false;
+ }
+ platform_leave(1);
+ case ATOMIC_STEP_SYSCORE_RESUME:
+ syscore_resume();
+ case ATOMIC_STEP_IRQS:
+ local_irq_enable();
+ case ATOMIC_STEP_CPU_HOTPLUG:
+ enable_nonboot_cpus();
+ case ATOMIC_STEP_PLATFORM_FINISH:
+ if (!suspend_time && error & 2)
+ platform_restore_cleanup(1);
+ else
+ platform_finish(1);
+ dpm_resume_start(msg);
+ case ATOMIC_STEP_DEVICE_RESUME:
+ if (suspend_time && (error & 2))
+ platform_recover(1);
+ dpm_resume(msg);
+ if (!toi_in_suspend()) {
+ dpm_resume_end(PMSG_RECOVER);
+ }
+ if (error || !toi_in_suspend()) {
+ pm_restore_gfp_mask();
+ }
+ resume_console();
+ case ATOMIC_STEP_DPM_COMPLETE:
+ dpm_complete(msg);
+ case ATOMIC_STEP_PLATFORM_END:
+ platform_end(1);
+
+ toi_prepare_status(DONT_CLEAR_BAR, "Post atomic.");
+ }
+}