[PATCH] md: Allow the write_mostly flag to be set via sysfs
It appears in /sys/mdX/md/dev-YYY/state
and can be set or cleared by writing 'writemostly' or '-writemostly'
respectively.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 8603c06..331b1bc 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1737,6 +1737,10 @@
len += sprintf(page+len, "%sin_sync",sep);
sep = ",";
}
+ if (test_bit(WriteMostly, &rdev->flags)) {
+ len += sprintf(page+len, "%swrite_mostly",sep);
+ sep = ",";
+ }
if (!test_bit(Faulty, &rdev->flags) &&
!test_bit(In_sync, &rdev->flags)) {
len += sprintf(page+len, "%sspare", sep);
@@ -1751,6 +1755,8 @@
/* can write
* faulty - simulates and error
* remove - disconnects the device
+ * writemostly - sets write_mostly
+ * -writemostly - clears write_mostly
*/
int err = -EINVAL;
if (cmd_match(buf, "faulty") && rdev->mddev->pers) {
@@ -1766,6 +1772,12 @@
md_new_event(mddev);
err = 0;
}
+ } else if (cmd_match(buf, "writemostly")) {
+ set_bit(WriteMostly, &rdev->flags);
+ err = 0;
+ } else if (cmd_match(buf, "-writemostly")) {
+ clear_bit(WriteMostly, &rdev->flags);
+ err = 0;
}
return err ? err : len;
}