diff options
Diffstat (limited to 'kernel/power/tuxonice_atomic_copy.c')
| -rw-r--r-- | kernel/power/tuxonice_atomic_copy.c | 469 |
1 files changed, 469 insertions, 0 deletions
diff --git a/kernel/power/tuxonice_atomic_copy.c b/kernel/power/tuxonice_atomic_copy.c new file mode 100644 index 000000000..5845217f8 --- /dev/null +++ b/kernel/power/tuxonice_atomic_copy.c @@ -0,0 +1,469 @@ +/* + * 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."); + } +} |