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-rw-r--r--kernel/power/tuxonice_swap.c474
1 files changed, 474 insertions, 0 deletions
diff --git a/kernel/power/tuxonice_swap.c b/kernel/power/tuxonice_swap.c
new file mode 100644
index 000000000..9f555c932
--- /dev/null
+++ b/kernel/power/tuxonice_swap.c
@@ -0,0 +1,474 @@
+/*
+ * kernel/power/tuxonice_swap.c
+ *
+ * Copyright (C) 2004-2015 Nigel Cunningham (nigel at nigelcunningham com au)
+ *
+ * Distributed under GPLv2.
+ *
+ * This file encapsulates functions for usage of swap space as a
+ * backing store.
+ */
+
+#include <linux/suspend.h>
+#include <linux/blkdev.h>
+#include <linux/swapops.h>
+#include <linux/swap.h>
+#include <linux/syscalls.h>
+#include <linux/fs_uuid.h>
+
+#include "tuxonice.h"
+#include "tuxonice_sysfs.h"
+#include "tuxonice_modules.h"
+#include "tuxonice_io.h"
+#include "tuxonice_ui.h"
+#include "tuxonice_extent.h"
+#include "tuxonice_bio.h"
+#include "tuxonice_alloc.h"
+#include "tuxonice_builtin.h"
+
+static struct toi_module_ops toi_swapops;
+
+/* For swapfile automatically swapon/off'd. */
+static char swapfilename[255] = "";
+static int toi_swapon_status;
+
+/* Swap Pages */
+static unsigned long swap_allocated;
+
+static struct sysinfo swapinfo;
+
+static int is_ram_backed(struct swap_info_struct *si)
+{
+ if (!strncmp(si->bdev->bd_disk->disk_name, "ram", 3) ||
+ !strncmp(si->bdev->bd_disk->disk_name, "zram", 4))
+ return 1;
+
+ return 0;
+}
+
+/**
+ * enable_swapfile: Swapon the user specified swapfile prior to hibernating.
+ *
+ * Activate the given swapfile if it wasn't already enabled. Remember whether
+ * we really did swapon it for swapoffing later.
+ */
+static void enable_swapfile(void)
+{
+ int activateswapresult = -EINVAL;
+
+ if (swapfilename[0]) {
+ /* Attempt to swap on with maximum priority */
+ activateswapresult = sys_swapon(swapfilename, 0xFFFF);
+ if (activateswapresult && activateswapresult != -EBUSY)
+ printk(KERN_ERR "TuxOnIce: The swapfile/partition "
+ "specified by /sys/power/tuxonice/swap/swapfile"
+ " (%s) could not be turned on (error %d). "
+ "Attempting to continue.\n",
+ swapfilename, activateswapresult);
+ if (!activateswapresult)
+ toi_swapon_status = 1;
+ }
+}
+
+/**
+ * disable_swapfile: Swapoff any file swaponed at the start of the cycle.
+ *
+ * If we did successfully swapon a file at the start of the cycle, swapoff
+ * it now (finishing up).
+ */
+static void disable_swapfile(void)
+{
+ if (!toi_swapon_status)
+ return;
+
+ sys_swapoff(swapfilename);
+ toi_swapon_status = 0;
+}
+
+static int add_blocks_to_extent_chain(struct toi_bdev_info *chain,
+ unsigned long start, unsigned long end)
+{
+ if (test_action_state(TOI_TEST_BIO))
+ toi_message(TOI_IO, TOI_VERBOSE, 0, "Adding extent %lu-%lu to "
+ "chain %p.", start << chain->bmap_shift,
+ end << chain->bmap_shift, chain);
+
+ return toi_add_to_extent_chain(&chain->blocks, start, end);
+}
+
+
+static int get_main_pool_phys_params(struct toi_bdev_info *chain)
+{
+ struct hibernate_extent *extentpointer = NULL;
+ unsigned long address, extent_min = 0, extent_max = 0;
+ int empty = 1;
+
+ toi_message(TOI_IO, TOI_VERBOSE, 0, "get main pool phys params for "
+ "chain %d.", chain->allocator_index);
+
+ if (!chain->allocations.first)
+ return 0;
+
+ if (chain->blocks.first)
+ toi_put_extent_chain(&chain->blocks);
+
+ toi_extent_for_each(&chain->allocations, extentpointer, address) {
+ swp_entry_t swap_address = (swp_entry_t) { address };
+ struct block_device *bdev;
+ sector_t new_sector = map_swap_entry(swap_address, &bdev);
+
+ if (empty) {
+ empty = 0;
+ extent_min = extent_max = new_sector;
+ continue;
+ }
+
+ if (new_sector == extent_max + 1) {
+ extent_max++;
+ continue;
+ }
+
+ if (add_blocks_to_extent_chain(chain, extent_min, extent_max)) {
+ printk(KERN_ERR "Out of memory while making block "
+ "chains.\n");
+ return -ENOMEM;
+ }
+
+ extent_min = new_sector;
+ extent_max = new_sector;
+ }
+
+ if (!empty &&
+ add_blocks_to_extent_chain(chain, extent_min, extent_max)) {
+ printk(KERN_ERR "Out of memory while making block chains.\n");
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/*
+ * Like si_swapinfo, except that we don't include ram backed swap (compcache!)
+ * and don't need to use the spinlocks (userspace is stopped when this
+ * function is called).
+ */
+void si_swapinfo_no_compcache(void)
+{
+ unsigned int i;
+
+ si_swapinfo(&swapinfo);
+ swapinfo.freeswap = 0;
+ swapinfo.totalswap = 0;
+
+ for (i = 0; i < MAX_SWAPFILES; i++) {
+ struct swap_info_struct *si = get_swap_info_struct(i);
+ if (si && (si->flags & SWP_WRITEOK) && !is_ram_backed(si)) {
+ swapinfo.totalswap += si->inuse_pages;
+ swapinfo.freeswap += si->pages - si->inuse_pages;
+ }
+ }
+}
+/*
+ * We can't just remember the value from allocation time, because other
+ * processes might have allocated swap in the mean time.
+ */
+static unsigned long toi_swap_storage_available(void)
+{
+ toi_message(TOI_IO, TOI_VERBOSE, 0, "In toi_swap_storage_available.");
+ si_swapinfo_no_compcache();
+ return swapinfo.freeswap + swap_allocated;
+}
+
+static int toi_swap_initialise(int starting_cycle)
+{
+ if (!starting_cycle)
+ return 0;
+
+ enable_swapfile();
+ return 0;
+}
+
+static void toi_swap_cleanup(int ending_cycle)
+{
+ if (!ending_cycle)
+ return;
+
+ disable_swapfile();
+}
+
+static void toi_swap_free_storage(struct toi_bdev_info *chain)
+{
+ /* Free swap entries */
+ struct hibernate_extent *extentpointer;
+ unsigned long extentvalue;
+
+ toi_message(TOI_IO, TOI_VERBOSE, 0, "Freeing storage for chain %p.",
+ chain);
+
+ swap_allocated -= chain->allocations.size;
+ toi_extent_for_each(&chain->allocations, extentpointer, extentvalue)
+ swap_free((swp_entry_t) { extentvalue });
+
+ toi_put_extent_chain(&chain->allocations);
+}
+
+static void free_swap_range(unsigned long min, unsigned long max)
+{
+ int j;
+
+ for (j = min; j <= max; j++)
+ swap_free((swp_entry_t) { j });
+ swap_allocated -= (max - min + 1);
+}
+
+/*
+ * Allocation of a single swap type. Swap priorities are handled at the higher
+ * level.
+ */
+static int toi_swap_allocate_storage(struct toi_bdev_info *chain,
+ unsigned long request)
+{
+ unsigned long gotten = 0;
+
+ toi_message(TOI_IO, TOI_VERBOSE, 0, " Swap allocate storage: Asked to"
+ " allocate %lu pages from device %d.", request,
+ chain->allocator_index);
+
+ while (gotten < request) {
+ swp_entry_t start, end;
+ if (0) {
+ /* Broken at the moment for SSDs */
+ get_swap_range_of_type(chain->allocator_index, &start, &end,
+ request - gotten + 1);
+ } else {
+ start = end = get_swap_page_of_type(chain->allocator_index);
+ }
+ if (start.val) {
+ int added = end.val - start.val + 1;
+ if (toi_add_to_extent_chain(&chain->allocations,
+ start.val, end.val)) {
+ printk(KERN_INFO "Failed to allocate extent for "
+ "%lu-%lu.\n", start.val, end.val);
+ free_swap_range(start.val, end.val);
+ break;
+ }
+ gotten += added;
+ swap_allocated += added;
+ } else
+ break;
+ }
+
+ toi_message(TOI_IO, TOI_VERBOSE, 0, " Allocated %lu pages.", gotten);
+ return gotten;
+}
+
+static int toi_swap_register_storage(void)
+{
+ int i, result = 0;
+
+ toi_message(TOI_IO, TOI_VERBOSE, 0, "toi_swap_register_storage.");
+ for (i = 0; i < MAX_SWAPFILES; i++) {
+ struct swap_info_struct *si = get_swap_info_struct(i);
+ struct toi_bdev_info *devinfo;
+ unsigned char *p;
+ unsigned char buf[256];
+ struct fs_info *fs_info;
+
+ if (!si || !(si->flags & SWP_WRITEOK) || is_ram_backed(si))
+ continue;
+
+ devinfo = toi_kzalloc(39, sizeof(struct toi_bdev_info),
+ GFP_ATOMIC);
+ if (!devinfo) {
+ printk("Failed to allocate devinfo struct for swap "
+ "device %d.\n", i);
+ return -ENOMEM;
+ }
+
+ devinfo->bdev = si->bdev;
+ devinfo->allocator = &toi_swapops;
+ devinfo->allocator_index = i;
+
+ fs_info = fs_info_from_block_dev(si->bdev);
+ if (fs_info && !IS_ERR(fs_info)) {
+ memcpy(devinfo->uuid, &fs_info->uuid, 16);
+ free_fs_info(fs_info);
+ } else
+ result = (int) PTR_ERR(fs_info);
+
+ if (!fs_info)
+ printk("fs_info from block dev returned %d.\n", result);
+ devinfo->dev_t = si->bdev->bd_dev;
+ devinfo->prio = si->prio;
+ devinfo->bmap_shift = 3;
+ devinfo->blocks_per_page = 1;
+
+ p = d_path(&si->swap_file->f_path, buf, sizeof(buf));
+ sprintf(devinfo->name, "swap on %s", p);
+
+ toi_message(TOI_IO, TOI_VERBOSE, 0, "Registering swap storage:"
+ " Device %d (%lx), prio %d.", i,
+ (unsigned long) devinfo->dev_t, devinfo->prio);
+ toi_bio_ops.register_storage(devinfo);
+ }
+
+ return 0;
+}
+
+static unsigned long toi_swap_free_unused_storage(struct toi_bdev_info *chain, unsigned long used)
+{
+ struct hibernate_extent *extentpointer = NULL;
+ unsigned long extentvalue;
+ unsigned long i = 0, first_freed = 0;
+
+ toi_extent_for_each(&chain->allocations, extentpointer, extentvalue) {
+ i++;
+ if (i > used) {
+ swap_free((swp_entry_t) { extentvalue });
+ if (!first_freed)
+ first_freed = extentvalue;
+ }
+ }
+
+ return first_freed;
+}
+
+/*
+ * workspace_size
+ *
+ * Description:
+ * Returns the number of bytes of RAM needed for this
+ * code to do its work. (Used when calculating whether
+ * we have enough memory to be able to hibernate & resume).
+ *
+ */
+static int toi_swap_memory_needed(void)
+{
+ return 1;
+}
+
+/*
+ * Print debug info
+ *
+ * Description:
+ */
+static int toi_swap_print_debug_stats(char *buffer, int size)
+{
+ int len = 0;
+
+ len = scnprintf(buffer, size, "- Swap Allocator enabled.\n");
+ if (swapfilename[0])
+ len += scnprintf(buffer+len, size-len,
+ " Attempting to automatically swapon: %s.\n",
+ swapfilename);
+
+ si_swapinfo_no_compcache();
+
+ len += scnprintf(buffer+len, size-len,
+ " Swap available for image: %lu pages.\n",
+ swapinfo.freeswap + swap_allocated);
+
+ return len;
+}
+
+static int header_locations_read_sysfs(const char *page, int count)
+{
+ int i, printedpartitionsmessage = 0, len = 0, haveswap = 0;
+ struct inode *swapf = NULL;
+ int zone;
+ char *path_page = (char *) toi_get_free_page(10, GFP_KERNEL);
+ char *path, *output = (char *) page;
+ int path_len;
+
+ if (!page)
+ return 0;
+
+ for (i = 0; i < MAX_SWAPFILES; i++) {
+ struct swap_info_struct *si = get_swap_info_struct(i);
+
+ if (!si || !(si->flags & SWP_WRITEOK))
+ continue;
+
+ if (S_ISBLK(si->swap_file->f_mapping->host->i_mode)) {
+ haveswap = 1;
+ if (!printedpartitionsmessage) {
+ len += sprintf(output + len,
+ "For swap partitions, simply use the "
+ "format: resume=swap:/dev/hda1.\n");
+ printedpartitionsmessage = 1;
+ }
+ } else {
+ path_len = 0;
+
+ path = d_path(&si->swap_file->f_path, path_page,
+ PAGE_SIZE);
+ path_len = snprintf(path_page, PAGE_SIZE, "%s", path);
+
+ haveswap = 1;
+ swapf = si->swap_file->f_mapping->host;
+ zone = bmap(swapf, 0);
+ if (!zone) {
+ len += sprintf(output + len,
+ "Swapfile %s has been corrupted. Reuse"
+ " mkswap on it and try again.\n",
+ path_page);
+ } else {
+ char name_buffer[BDEVNAME_SIZE];
+ len += sprintf(output + len,
+ "For swapfile `%s`,"
+ " use resume=swap:/dev/%s:0x%x.\n",
+ path_page,
+ bdevname(si->bdev, name_buffer),
+ zone << (swapf->i_blkbits - 9));
+ }
+ }
+ }
+
+ if (!haveswap)
+ len = sprintf(output, "You need to turn on swap partitions "
+ "before examining this file.\n");
+
+ toi_free_page(10, (unsigned long) path_page);
+ return len;
+}
+
+static struct toi_sysfs_data sysfs_params[] = {
+ SYSFS_STRING("swapfilename", SYSFS_RW, swapfilename, 255, 0, NULL),
+ SYSFS_CUSTOM("headerlocations", SYSFS_READONLY,
+ header_locations_read_sysfs, NULL, 0, NULL),
+ SYSFS_INT("enabled", SYSFS_RW, &toi_swapops.enabled, 0, 1, 0,
+ attempt_to_parse_resume_device2),
+};
+
+static struct toi_bio_allocator_ops toi_bio_swapops = {
+ .register_storage = toi_swap_register_storage,
+ .storage_available = toi_swap_storage_available,
+ .allocate_storage = toi_swap_allocate_storage,
+ .bmap = get_main_pool_phys_params,
+ .free_storage = toi_swap_free_storage,
+ .free_unused_storage = toi_swap_free_unused_storage,
+};
+
+static struct toi_module_ops toi_swapops = {
+ .type = BIO_ALLOCATOR_MODULE,
+ .name = "swap storage",
+ .directory = "swap",
+ .module = THIS_MODULE,
+ .memory_needed = toi_swap_memory_needed,
+ .print_debug_info = toi_swap_print_debug_stats,
+ .initialise = toi_swap_initialise,
+ .cleanup = toi_swap_cleanup,
+ .bio_allocator_ops = &toi_bio_swapops,
+
+ .sysfs_data = sysfs_params,
+ .num_sysfs_entries = sizeof(sysfs_params) /
+ sizeof(struct toi_sysfs_data),
+};
+
+/* ---- Registration ---- */
+static __init int toi_swap_load(void)
+{
+ return toi_register_module(&toi_swapops);
+}
+
+late_initcall(toi_swap_load);
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