Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 466 insertions, 0 deletions

diff --git a/kernel/power/user.c b/kernel/power/user.c
new file mode 100644
index 0000000000..3a4e70366f
--- /dev/null
+++ b/kernel/power/user.c
@@ -0,0 +1,466 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/kernel/power/user.c
+ *
+ * This file provides the user space interface for software suspend/resume.
+ *
+ * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl>
+ */
+
+#include <linux/suspend.h>
+#include <linux/reboot.h>
+#include <linux/string.h>
+#include <linux/device.h>
+#include <linux/miscdevice.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
+#include <linux/pm.h>
+#include <linux/fs.h>
+#include <linux/compat.h>
+#include <linux/console.h>
+#include <linux/cpu.h>
+#include <linux/freezer.h>
+
+#include <linux/uaccess.h>
+
+#include "power.h"
+
+static bool need_wait;
+
+static struct snapshot_data {
+	struct snapshot_handle handle;
+	int swap;
+	int mode;
+	bool frozen;
+	bool ready;
+	bool platform_support;
+	bool free_bitmaps;
+	dev_t dev;
+} snapshot_state;
+
+int is_hibernate_resume_dev(dev_t dev)
+{
+	return hibernation_available() && snapshot_state.dev == dev;
+}
+
+static int snapshot_open(struct inode *inode, struct file *filp)
+{
+	struct snapshot_data *data;
+	unsigned int sleep_flags;
+	int error;
+
+	if (!hibernation_available())
+		return -EPERM;
+
+	sleep_flags = lock_system_sleep();
+
+	if (!hibernate_acquire()) {
+		error = -EBUSY;
+		goto Unlock;
+	}
+
+	if ((filp->f_flags & O_ACCMODE) == O_RDWR) {
+		hibernate_release();
+		error = -ENOSYS;
+		goto Unlock;
+	}
+	nonseekable_open(inode, filp);
+	data = &snapshot_state;
+	filp->private_data = data;
+	memset(&data->handle, 0, sizeof(struct snapshot_handle));
+	if ((filp->f_flags & O_ACCMODE) == O_RDONLY) {
+		/* Hibernating.  The image device should be accessible. */
+		data->swap = swap_type_of(swsusp_resume_device, 0);
+		data->mode = O_RDONLY;
+		data->free_bitmaps = false;
+		error = pm_notifier_call_chain_robust(PM_HIBERNATION_PREPARE, PM_POST_HIBERNATION);
+	} else {
+		/*
+		 * Resuming.  We may need to wait for the image device to
+		 * appear.
+		 */
+		need_wait = true;
+
+		data->swap = -1;
+		data->mode = O_WRONLY;
+		error = pm_notifier_call_chain_robust(PM_RESTORE_PREPARE, PM_POST_RESTORE);
+		if (!error) {
+			error = create_basic_memory_bitmaps();
+			data->free_bitmaps = !error;
+		}
+	}
+	if (error)
+		hibernate_release();
+
+	data->frozen = false;
+	data->ready = false;
+	data->platform_support = false;
+	data->dev = 0;
+
+ Unlock:
+	unlock_system_sleep(sleep_flags);
+
+	return error;
+}
+
+static int snapshot_release(struct inode *inode, struct file *filp)
+{
+	struct snapshot_data *data;
+	unsigned int sleep_flags;
+
+	sleep_flags = lock_system_sleep();
+
+	swsusp_free();
+	data = filp->private_data;
+	data->dev = 0;
+	free_all_swap_pages(data->swap);
+	if (data->frozen) {
+		pm_restore_gfp_mask();
+		free_basic_memory_bitmaps();
+		thaw_processes();
+	} else if (data->free_bitmaps) {
+		free_basic_memory_bitmaps();
+	}
+	pm_notifier_call_chain(data->mode == O_RDONLY ?
+			PM_POST_HIBERNATION : PM_POST_RESTORE);
+	hibernate_release();
+
+	unlock_system_sleep(sleep_flags);
+
+	return 0;
+}
+
+static ssize_t snapshot_read(struct file *filp, char __user *buf,
+                             size_t count, loff_t *offp)
+{
+	loff_t pg_offp = *offp & ~PAGE_MASK;
+	struct snapshot_data *data;
+	unsigned int sleep_flags;
+	ssize_t res;
+
+	sleep_flags = lock_system_sleep();
+
+	data = filp->private_data;
+	if (!data->ready) {
+		res = -ENODATA;
+		goto Unlock;
+	}
+	if (!pg_offp) { /* on page boundary? */
+		res = snapshot_read_next(&data->handle);
+		if (res <= 0)
+			goto Unlock;
+	} else {
+		res = PAGE_SIZE - pg_offp;
+	}
+
+	res = simple_read_from_buffer(buf, count, &pg_offp,
+			data_of(data->handle), res);
+	if (res > 0)
+		*offp += res;
+
+ Unlock:
+	unlock_system_sleep(sleep_flags);
+
+	return res;
+}
+
+static ssize_t snapshot_write(struct file *filp, const char __user *buf,
+                              size_t count, loff_t *offp)
+{
+	loff_t pg_offp = *offp & ~PAGE_MASK;
+	struct snapshot_data *data;
+	unsigned long sleep_flags;
+	ssize_t res;
+
+	if (need_wait) {
+		wait_for_device_probe();
+		need_wait = false;
+	}
+
+	sleep_flags = lock_system_sleep();
+
+	data = filp->private_data;
+
+	if (!pg_offp) {
+		res = snapshot_write_next(&data->handle);
+		if (res <= 0)
+			goto unlock;
+	} else {
+		res = PAGE_SIZE;
+	}
+
+	if (!data_of(data->handle)) {
+		res = -EINVAL;
+		goto unlock;
+	}
+
+	res = simple_write_to_buffer(data_of(data->handle), res, &pg_offp,
+			buf, count);
+	if (res > 0)
+		*offp += res;
+unlock:
+	unlock_system_sleep(sleep_flags);
+
+	return res;
+}
+
+struct compat_resume_swap_area {
+	compat_loff_t offset;
+	u32 dev;
+} __packed;
+
+static int snapshot_set_swap_area(struct snapshot_data *data,
+		void __user *argp)
+{
+	sector_t offset;
+	dev_t swdev;
+
+	if (swsusp_swap_in_use())
+		return -EPERM;
+
+	if (in_compat_syscall()) {
+		struct compat_resume_swap_area swap_area;
+
+		if (copy_from_user(&swap_area, argp, sizeof(swap_area)))
+			return -EFAULT;
+		swdev = new_decode_dev(swap_area.dev);
+		offset = swap_area.offset;
+	} else {
+		struct resume_swap_area swap_area;
+
+		if (copy_from_user(&swap_area, argp, sizeof(swap_area)))
+			return -EFAULT;
+		swdev = new_decode_dev(swap_area.dev);
+		offset = swap_area.offset;
+	}
+
+	/*
+	 * User space encodes device types as two-byte values,
+	 * so we need to recode them
+	 */
+	data->swap = swap_type_of(swdev, offset);
+	if (data->swap < 0)
+		return swdev ? -ENODEV : -EINVAL;
+	data->dev = swdev;
+	return 0;
+}
+
+static long snapshot_ioctl(struct file *filp, unsigned int cmd,
+							unsigned long arg)
+{
+	int error = 0;
+	struct snapshot_data *data;
+	loff_t size;
+	sector_t offset;
+
+	if (need_wait) {
+		wait_for_device_probe();
+		need_wait = false;
+	}
+
+	if (_IOC_TYPE(cmd) != SNAPSHOT_IOC_MAGIC)
+		return -ENOTTY;
+	if (_IOC_NR(cmd) > SNAPSHOT_IOC_MAXNR)
+		return -ENOTTY;
+	if (!capable(CAP_SYS_ADMIN))
+		return -EPERM;
+
+	if (!mutex_trylock(&system_transition_mutex))
+		return -EBUSY;
+
+	lock_device_hotplug();
+	data = filp->private_data;
+
+	switch (cmd) {
+
+	case SNAPSHOT_FREEZE:
+		if (data->frozen)
+			break;
+
+		ksys_sync_helper();
+
+		error = freeze_processes();
+		if (error)
+			break;
+
+		error = create_basic_memory_bitmaps();
+		if (error)
+			thaw_processes();
+		else
+			data->frozen = true;
+
+		break;
+
+	case SNAPSHOT_UNFREEZE:
+		if (!data->frozen || data->ready)
+			break;
+		pm_restore_gfp_mask();
+		free_basic_memory_bitmaps();
+		data->free_bitmaps = false;
+		thaw_processes();
+		data->frozen = false;
+		break;
+
+	case SNAPSHOT_CREATE_IMAGE:
+		if (data->mode != O_RDONLY || !data->frozen  || data->ready) {
+			error = -EPERM;
+			break;
+		}
+		pm_restore_gfp_mask();
+		error = hibernation_snapshot(data->platform_support);
+		if (!error) {
+			error = put_user(in_suspend, (int __user *)arg);
+			data->ready = !freezer_test_done && !error;
+			freezer_test_done = false;
+		}
+		break;
+
+	case SNAPSHOT_ATOMIC_RESTORE:
+		snapshot_write_finalize(&data->handle);
+		if (data->mode != O_WRONLY || !data->frozen ||
+		    !snapshot_image_loaded(&data->handle)) {
+			error = -EPERM;
+			break;
+		}
+		error = hibernation_restore(data->platform_support);
+		break;
+
+	case SNAPSHOT_FREE:
+		swsusp_free();
+		memset(&data->handle, 0, sizeof(struct snapshot_handle));
+		data->ready = false;
+		/*
+		 * It is necessary to thaw kernel threads here, because
+		 * SNAPSHOT_CREATE_IMAGE may be invoked directly after
+		 * SNAPSHOT_FREE.  In that case, if kernel threads were not
+		 * thawed, the preallocation of memory carried out by
+		 * hibernation_snapshot() might run into problems (i.e. it
+		 * might fail or even deadlock).
+		 */
+		thaw_kernel_threads();
+		break;
+
+	case SNAPSHOT_PREF_IMAGE_SIZE:
+		image_size = arg;
+		break;
+
+	case SNAPSHOT_GET_IMAGE_SIZE:
+		if (!data->ready) {
+			error = -ENODATA;
+			break;
+		}
+		size = snapshot_get_image_size();
+		size <<= PAGE_SHIFT;
+		error = put_user(size, (loff_t __user *)arg);
+		break;
+
+	case SNAPSHOT_AVAIL_SWAP_SIZE:
+		size = count_swap_pages(data->swap, 1);
+		size <<= PAGE_SHIFT;
+		error = put_user(size, (loff_t __user *)arg);
+		break;
+
+	case SNAPSHOT_ALLOC_SWAP_PAGE:
+		if (data->swap < 0 || data->swap >= MAX_SWAPFILES) {
+			error = -ENODEV;
+			break;
+		}
+		offset = alloc_swapdev_block(data->swap);
+		if (offset) {
+			offset <<= PAGE_SHIFT;
+			error = put_user(offset, (loff_t __user *)arg);
+		} else {
+			error = -ENOSPC;
+		}
+		break;
+
+	case SNAPSHOT_FREE_SWAP_PAGES:
+		if (data->swap < 0 || data->swap >= MAX_SWAPFILES) {
+			error = -ENODEV;
+			break;
+		}
+		free_all_swap_pages(data->swap);
+		break;
+
+	case SNAPSHOT_S2RAM:
+		if (!data->frozen) {
+			error = -EPERM;
+			break;
+		}
+		/*
+		 * Tasks are frozen and the notifiers have been called with
+		 * PM_HIBERNATION_PREPARE
+		 */
+		error = suspend_devices_and_enter(PM_SUSPEND_MEM);
+		data->ready = false;
+		break;
+
+	case SNAPSHOT_PLATFORM_SUPPORT:
+		data->platform_support = !!arg;
+		break;
+
+	case SNAPSHOT_POWER_OFF:
+		if (data->platform_support)
+			error = hibernation_platform_enter();
+		break;
+
+	case SNAPSHOT_SET_SWAP_AREA:
+		error = snapshot_set_swap_area(data, (void __user *)arg);
+		break;
+
+	default:
+		error = -ENOTTY;
+
+	}
+
+	unlock_device_hotplug();
+	mutex_unlock(&system_transition_mutex);
+
+	return error;
+}
+
+#ifdef CONFIG_COMPAT
+static long
+snapshot_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	BUILD_BUG_ON(sizeof(loff_t) != sizeof(compat_loff_t));
+
+	switch (cmd) {
+	case SNAPSHOT_GET_IMAGE_SIZE:
+	case SNAPSHOT_AVAIL_SWAP_SIZE:
+	case SNAPSHOT_ALLOC_SWAP_PAGE:
+	case SNAPSHOT_CREATE_IMAGE:
+	case SNAPSHOT_SET_SWAP_AREA:
+		return snapshot_ioctl(file, cmd,
+				      (unsigned long) compat_ptr(arg));
+	default:
+		return snapshot_ioctl(file, cmd, arg);
+	}
+}
+#endif /* CONFIG_COMPAT */
+
+static const struct file_operations snapshot_fops = {
+	.open = snapshot_open,
+	.release = snapshot_release,
+	.read = snapshot_read,
+	.write = snapshot_write,
+	.llseek = no_llseek,
+	.unlocked_ioctl = snapshot_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl = snapshot_compat_ioctl,
+#endif
+};
+
+static struct miscdevice snapshot_device = {
+	.minor = SNAPSHOT_MINOR,
+	.name = "snapshot",
+	.fops = &snapshot_fops,
+};
+
+static int __init snapshot_device_init(void)
+{
+	return misc_register(&snapshot_device);
+};
+
+device_initcall(snapshot_device_init);