PM / hibernate: use name_to_dev_t to parse resume

Use the name_to_dev_t call to parse the device name echo'd to
to /sys/power/resume.  This imitates the method used in hibernate.c
in software_resume, and allows the resume partition to be specified
using other equivalent device formats as well.  By allowing
/sys/debug/resume to accept the same syntax as the resume=device
parameter, we can parse the resume=device in the init script and
use the resume device directly from the kernel command line.

Signed-off-by: Sebastian Capella <sebastian.capella@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 37170d4..f4f2073 100644 (file)
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -973,16 +973,20 @@ static ssize_t resume_show(struct kobject *kobj, struct kobj_attribute *attr,
 static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
                            const char *buf, size_t n)
 {
-       unsigned int maj, min;
        dev_t res;
-       int ret = -EINVAL;
+       int len = n;
+       char *name;
 
-       if (sscanf(buf, "%u:%u", &maj, &min) != 2)
-               goto out;
+       if (len && buf[len-1] == '\n')
+               len--;
+       name = kstrndup(buf, len, GFP_KERNEL);
+       if (!name)
+               return -ENOMEM;
 
-       res = MKDEV(maj,min);
-       if (maj != MAJOR(res) || min != MINOR(res))
-               goto out;
+       res = name_to_dev_t(name);
+       kfree(name);
+       if (!res)
+               return -EINVAL;
 
        lock_system_sleep();
        swsusp_resume_device = res;
@@ -990,9 +994,7 @@ static ssize_t resume_store(struct kobject *kobj, struct kobj_attribute *attr,
        printk(KERN_INFO "PM: Starting manual resume from disk\n");
        noresume = 0;
        software_resume();
-       ret = n;
- out:
-       return ret;
+       return n;
 }
 
 power_attr(resume);