From a6e15a39048ec3229b9a53425f4384f55f6cc1b3 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Fri, 13 Jun 2014 13:30:35 -0700 Subject: PM / hibernate: introduce "nohibernate" boot parameter To support using kernel features that are not compatible with hibernation, this creates the "nohibernate" kernel boot parameter to disable both hibernation and resume. This allows hibernation support to be a boot-time choice instead of only a compile-time choice. Signed-off-by: Kees Cook Acked-by: Pavel Machek Signed-off-by: Rafael J. Wysocki --- kernel/power/hibernate.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) (limited to 'kernel/power/hibernate.c') diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 49e0a20fd010..258f492f0347 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -35,6 +35,7 @@ static int nocompress; static int noresume; +static int nohibernate; static int resume_wait; static unsigned int resume_delay; static char resume_file[256] = CONFIG_PM_STD_PARTITION; @@ -62,6 +63,11 @@ bool freezer_test_done; static const struct platform_hibernation_ops *hibernation_ops; +bool hibernation_available(void) +{ + return (nohibernate == 0); +} + /** * hibernation_set_ops - Set the global hibernate operations. * @ops: Hibernation operations to use in subsequent hibernation transitions. @@ -642,6 +648,11 @@ int hibernate(void) { int error; + if (!hibernation_available()) { + pr_debug("PM: Hibernation not available.\n"); + return -EPERM; + } + lock_system_sleep(); /* The snapshot device should not be opened while we're running */ if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { @@ -734,7 +745,7 @@ static int software_resume(void) /* * If the user said "noresume".. bail out early. */ - if (noresume) + if (noresume || !hibernation_available()) return 0; /* @@ -900,6 +911,9 @@ static ssize_t disk_show(struct kobject *kobj, struct kobj_attribute *attr, int i; char *start = buf; + if (!hibernation_available()) + return sprintf(buf, "[disabled]\n"); + for (i = HIBERNATION_FIRST; i <= HIBERNATION_MAX; i++) { if (!hibernation_modes[i]) continue; @@ -934,6 +948,9 @@ static ssize_t disk_store(struct kobject *kobj, struct kobj_attribute *attr, char *p; int mode = HIBERNATION_INVALID; + if (!hibernation_available()) + return -EPERM; + p = memchr(buf, '\n', n); len = p ? p - buf : n; @@ -1101,6 +1118,10 @@ static int __init hibernate_setup(char *str) noresume = 1; else if (!strncmp(str, "nocompress", 10)) nocompress = 1; + else if (!strncmp(str, "no", 2)) { + noresume = 1; + nohibernate = 1; + } return 1; } @@ -1125,9 +1146,17 @@ static int __init resumedelay_setup(char *str) return 1; } +static int __init nohibernate_setup(char *str) +{ + noresume = 1; + nohibernate = 1; + return 1; +} + __setup("noresume", noresume_setup); __setup("resume_offset=", resume_offset_setup); __setup("resume=", resume_setup); __setup("hibernate=", hibernate_setup); __setup("resumewait", resumewait_setup); __setup("resumedelay=", resumedelay_setup); +__setup("nohibernate", nohibernate_setup); -- cgit