UBI: Add ro-mode sysfs attribute
On serious situations, UBI may detect serious device corruption,
and switch to read-only mode to protect the data and allow debugging.
This commit exposes this ro-mode on sysfs, so it can be obtained
by userspace tools.
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Richard Weinberger <richard@nod.at>
diff --git a/Documentation/ABI/stable/sysfs-class-ubi b/Documentation/ABI/stable/sysfs-class-ubi
index 18d471d..a6b3240 100644
--- a/Documentation/ABI/stable/sysfs-class-ubi
+++ b/Documentation/ABI/stable/sysfs-class-ubi
@@ -107,6 +107,15 @@
Description:
Number of physical eraseblocks reserved for bad block handling.
+What: /sys/class/ubi/ubiX/ro_mode
+Date: April 2016
+KernelVersion: 4.7
+Contact: linux-mtd@lists.infradead.org
+Description:
+ Contains ASCII "1\n" if the read-only flag is set on this
+ device, and "0\n" if it is cleared. UBI devices mark themselves
+ as read-only when they detect an unrecoverable error.
+
What: /sys/class/ubi/ubiX/total_eraseblocks
Date: July 2006
KernelVersion: 2.6.22
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 22fd19c..7091fca 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -149,6 +149,8 @@
__ATTR(bgt_enabled, S_IRUGO, dev_attribute_show, NULL);
static struct device_attribute dev_mtd_num =
__ATTR(mtd_num, S_IRUGO, dev_attribute_show, NULL);
+static struct device_attribute dev_ro_mode =
+ __ATTR(ro_mode, S_IRUGO, dev_attribute_show, NULL);
/**
* ubi_volume_notify - send a volume change notification.
@@ -385,6 +387,8 @@
ret = sprintf(buf, "%d\n", ubi->thread_enabled);
else if (attr == &dev_mtd_num)
ret = sprintf(buf, "%d\n", ubi->mtd->index);
+ else if (attr == &dev_ro_mode)
+ ret = sprintf(buf, "%d\n", ubi->ro_mode);
else
ret = -EINVAL;
@@ -404,6 +408,7 @@
&dev_min_io_size.attr,
&dev_bgt_enabled.attr,
&dev_mtd_num.attr,
+ &dev_ro_mode.attr,
NULL
};
ATTRIBUTE_GROUPS(ubi_dev);