[S390] cio: fix channel path vary

Channel path vary is currently broken: channel paths which are varied
offline are still used by Linux. The reason for this is that:

 * the path mask indicating which paths of an I/O device can be used
   is reset by each internal I/O request
 * the logic that checks if a path group is already in its designated
   target state incorrectly interprets the result "is correctly set"
   as "is correctly set and available"

Fix this by resetting the path mask only for internal I/O requests
which affect the path mask and by correcting the pgid check logic.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/s390/cio/io_sch.h b/drivers/s390/cio/io_sch.h
index d72ae4c93af..b9ce712a7f2 100644
--- a/drivers/s390/cio/io_sch.h
+++ b/drivers/s390/cio/io_sch.h
@@ -150,6 +150,7 @@ struct ccw_device_private {
         struct ccw_request req;         /* internal I/O request */
         int iretry;
         u8 pgid_valid_mask;             /* mask of valid PGIDs */
+        u8 pgid_todo_mask;              /* mask of PGIDs to be adjusted */
         struct {
                 unsigned int fast:1;    /* post with "channel end" */
                 unsigned int repall:1;  /* report every interrupt status */