From: Kevin Corry <kevcorry@us.ibm.com>
Clarify the comment regarding the "next" field in struct dm_target_spec. The
"next" field has different behavior if you're performing a DM_TABLE_STATUS
command than it does if you're performing a DM_TABLE_LOAD command.
See populate_table() and retrieve_status() in drivers/md/dm-ioctl.c for more
details on how this field is used.
---
25-akpm/include/linux/dm-ioctl.h | 10 ++++++++--
1 files changed, 8 insertions(+), 2 deletions(-)
diff -puN include/linux/dm-ioctl.h~dm-clarify-a-comment include/linux/dm-ioctl.h
--- 25/include/linux/dm-ioctl.h~dm-clarify-a-comment Mon Apr 12 13:48:53 2004
+++ 25-akpm/include/linux/dm-ioctl.h Mon Apr 12 13:48:53 2004
@@ -129,8 +129,14 @@ struct dm_target_spec {
int32_t status; /* used when reading from kernel only */
/*
- * Offset in bytes (from the start of this struct) to
- * next target_spec.
+ * Location of the next dm_target_spec.
+ * - When specifying targets on a DM_TABLE_LOAD command, this value is
+ * the number of bytes from the start of the "current" dm_target_spec
+ * to the start of the "next" dm_target_spec.
+ * - When retrieving targets on a DM_TABLE_STATUS command, this value
+ * is the number of bytes from the start of the first dm_target_spec
+ * (that follows the dm_ioctl struct) to the start of the "next"
+ * dm_target_spec.
*/
uint32_t next;
_