[PATCH] dm: add debug macro
Add CONFIG_DM_DEBUG and DMDEBUG() macro.
Signed-off-by: Bryn Reeves <breeves@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 6dd31a2..949c71f 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -201,6 +201,14 @@
If unsure, say N.
+config DM_DEBUG
+ boolean "Device mapper debugging support"
+ depends on BLK_DEV_DM && EXPERIMENTAL
+ ---help---
+ Enable this for messages that may help debug device-mapper problems.
+
+ If unsure, say N.
+
config DM_CRYPT
tristate "Crypt target support"
depends on BLK_DEV_DM && EXPERIMENTAL
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index 3c03c0e..fe701c4 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -21,6 +21,11 @@
#define DMERR(f, arg...) printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
#define DMWARN(f, arg...) printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
#define DMINFO(f, arg...) printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
+#ifdef CONFIG_DM_DEBUG
+# define DMDEBUG(f, arg...) printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX " DEBUG: " f "\n", ## arg)
+#else
+# define DMDEBUG(f, arg...) do {} while (0)
+#endif
#define DMEMIT(x...) sz += ((sz >= maxlen) ? \
0 : scnprintf(result + sz, maxlen - sz, x))