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authorJiri Kosina <jkosina@suse.cz>2020-09-01 14:19:48 +0200
committerJiri Kosina <jkosina@suse.cz>2020-09-01 14:19:48 +0200
commitead5d1f4d877e92c051e1a1ade623d0d30e71619 (patch)
treecb9db5698a546e7b96f7d5bef5ce544629dd37a2 /kernel/power/hibernate.c
parentscif: Fix spelling of EACCES (diff)
parentMerge tag 'docs-5.9-3' of git://git.lwn.net/linux (diff)
downloadwireguard-linux-ead5d1f4d877e92c051e1a1ade623d0d30e71619.tar.xz
wireguard-linux-ead5d1f4d877e92c051e1a1ade623d0d30e71619.zip
Merge branch 'master' into for-next
Sync with Linus' branch in order to be able to apply fixups of more recent patches.
Diffstat (limited to '')
-rw-r--r--kernel/power/hibernate.c134
1 files changed, 125 insertions, 9 deletions
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 6dbeedb7354c..e7aa57fb2fdc 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -67,6 +67,18 @@ bool freezer_test_done;
static const struct platform_hibernation_ops *hibernation_ops;
+static atomic_t hibernate_atomic = ATOMIC_INIT(1);
+
+bool hibernate_acquire(void)
+{
+ return atomic_add_unless(&hibernate_atomic, -1, 0);
+}
+
+void hibernate_release(void)
+{
+ atomic_inc(&hibernate_atomic);
+}
+
bool hibernation_available(void)
{
return nohibernate == 0 && !security_locked_down(LOCKDOWN_HIBERNATION);
@@ -647,7 +659,7 @@ static void power_down(void)
break;
case HIBERNATION_PLATFORM:
hibernation_platform_enter();
- /* Fall through */
+ fallthrough;
case HIBERNATION_SHUTDOWN:
if (pm_power_off)
kernel_power_off();
@@ -678,7 +690,7 @@ static int load_image_and_restore(void)
error = swsusp_read(&flags);
swsusp_close(FMODE_READ);
if (!error)
- hibernation_restore(flags & SF_PLATFORM_MODE);
+ error = hibernation_restore(flags & SF_PLATFORM_MODE);
pr_err("Failed to load image, recovering.\n");
swsusp_free();
@@ -704,7 +716,7 @@ int hibernate(void)
lock_system_sleep();
/* The snapshot device should not be opened while we're running */
- if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+ if (!hibernate_acquire()) {
error = -EBUSY;
goto Unlock;
}
@@ -775,7 +787,7 @@ int hibernate(void)
Exit:
__pm_notifier_call_chain(PM_POST_HIBERNATION, nr_calls, NULL);
pm_restore_console();
- atomic_inc(&snapshot_device_available);
+ hibernate_release();
Unlock:
unlock_system_sleep();
pr_info("hibernation exit\n");
@@ -783,6 +795,103 @@ int hibernate(void)
return error;
}
+/**
+ * hibernate_quiet_exec - Execute a function with all devices frozen.
+ * @func: Function to execute.
+ * @data: Data pointer to pass to @func.
+ *
+ * Return the @func return value or an error code if it cannot be executed.
+ */
+int hibernate_quiet_exec(int (*func)(void *data), void *data)
+{
+ int error, nr_calls = 0;
+
+ lock_system_sleep();
+
+ if (!hibernate_acquire()) {
+ error = -EBUSY;
+ goto unlock;
+ }
+
+ pm_prepare_console();
+
+ error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls);
+ if (error) {
+ nr_calls--;
+ goto exit;
+ }
+
+ error = freeze_processes();
+ if (error)
+ goto exit;
+
+ lock_device_hotplug();
+
+ pm_suspend_clear_flags();
+
+ error = platform_begin(true);
+ if (error)
+ goto thaw;
+
+ error = freeze_kernel_threads();
+ if (error)
+ goto thaw;
+
+ error = dpm_prepare(PMSG_FREEZE);
+ if (error)
+ goto dpm_complete;
+
+ suspend_console();
+
+ error = dpm_suspend(PMSG_FREEZE);
+ if (error)
+ goto dpm_resume;
+
+ error = dpm_suspend_end(PMSG_FREEZE);
+ if (error)
+ goto dpm_resume;
+
+ error = platform_pre_snapshot(true);
+ if (error)
+ goto skip;
+
+ error = func(data);
+
+skip:
+ platform_finish(true);
+
+ dpm_resume_start(PMSG_THAW);
+
+dpm_resume:
+ dpm_resume(PMSG_THAW);
+
+ resume_console();
+
+dpm_complete:
+ dpm_complete(PMSG_THAW);
+
+ thaw_kernel_threads();
+
+thaw:
+ platform_end(true);
+
+ unlock_device_hotplug();
+
+ thaw_processes();
+
+exit:
+ __pm_notifier_call_chain(PM_POST_HIBERNATION, nr_calls, NULL);
+
+ pm_restore_console();
+
+ hibernate_release();
+
+unlock:
+ unlock_system_sleep();
+
+ return error;
+}
+EXPORT_SYMBOL_GPL(hibernate_quiet_exec);
/**
* software_resume - Resume from a saved hibernation image.
@@ -880,7 +989,7 @@ static int software_resume(void)
goto Unlock;
/* The snapshot device should not be opened while we're running */
- if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+ if (!hibernate_acquire()) {
error = -EBUSY;
swsusp_close(FMODE_READ);
goto Unlock;
@@ -898,13 +1007,20 @@ static int software_resume(void)
error = freeze_processes();
if (error)
goto Close_Finish;
+
+ error = freeze_kernel_threads();
+ if (error) {
+ thaw_processes();
+ goto Close_Finish;
+ }
+
error = load_image_and_restore();
thaw_processes();
Finish:
__pm_notifier_call_chain(PM_POST_RESTORE, nr_calls, NULL);
pm_restore_console();
pr_info("resume failed (%d)\n", error);
- atomic_inc(&snapshot_device_available);
+ hibernate_release();
/* For success case, the suspend path will release the lock */
Unlock:
mutex_unlock(&system_transition_mutex);
@@ -1043,7 +1159,7 @@ power_attr(disk);
static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
char *buf)
{
- return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
+ return sprintf(buf, "%d:%d\n", MAJOR(swsusp_resume_device),
MINOR(swsusp_resume_device));
}
@@ -1143,7 +1259,7 @@ static ssize_t reserved_size_store(struct kobject *kobj,
power_attr(reserved_size);
-static struct attribute * g[] = {
+static struct attribute *g[] = {
&disk_attr.attr,
&resume_offset_attr.attr,
&resume_attr.attr,
@@ -1171,7 +1287,7 @@ static int __init resume_setup(char *str)
if (noresume)
return 1;
- strncpy( resume_file, str, 255 );
+ strncpy(resume_file, str, 255);
return 1;
}