s390/cio: handle unknown pgroup state
When an attempt to query or modify the grouping state of a channel path
fails due to a timeout, we cannot be sure about its state. To get back to
a defined state, disband the whole path group and try again while excluding
the offending path.
Reviewed-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/cio/device_pgid.c b/drivers/s390/cio/device_pgid.c
index f12beb7..37ada05e 100644
--- a/drivers/s390/cio/device_pgid.c
+++ b/drivers/s390/cio/device_pgid.c
@@ -23,6 +23,8 @@
#define PGID_RETRIES 256
#define PGID_TIMEOUT (10 * HZ)
+static void verify_start(struct ccw_device *cdev);
+
/*
* Process path verification data and report result.
*/
@@ -142,6 +144,48 @@
req->cp = cp;
}
+static void pgid_wipeout_callback(struct ccw_device *cdev, void *data, int rc)
+{
+ if (rc) {
+ /* We don't know the path groups' state. Abort. */
+ verify_done(cdev, rc);
+ return;
+ }
+ /*
+ * Path groups have been reset. Restart path verification but
+ * leave paths in path_noirq_mask out.
+ */
+ cdev->private->flags.pgid_unknown = 0;
+ verify_start(cdev);
+}
+
+/*
+ * Reset pathgroups and restart path verification, leave unusable paths out.
+ */
+static void pgid_wipeout_start(struct ccw_device *cdev)
+{
+ struct subchannel *sch = to_subchannel(cdev->dev.parent);
+ struct ccw_dev_id *id = &cdev->private->dev_id;
+ struct ccw_request *req = &cdev->private->req;
+ u8 fn;
+
+ CIO_MSG_EVENT(2, "wipe: device 0.%x.%04x: pvm=%02x nim=%02x\n",
+ id->ssid, id->devno, cdev->private->pgid_valid_mask,
+ cdev->private->path_noirq_mask);
+
+ /* Initialize request data. */
+ memset(req, 0, sizeof(*req));
+ req->timeout = PGID_TIMEOUT;
+ req->maxretries = PGID_RETRIES;
+ req->lpm = sch->schib.pmcw.pam;
+ req->callback = pgid_wipeout_callback;
+ fn = SPID_FUNC_DISBAND;
+ if (cdev->private->flags.mpath)
+ fn |= SPID_FUNC_MULTI_PATH;
+ spid_build_cp(cdev, fn);
+ ccw_request_start(cdev);
+}
+
/*
* Perform establish/resign SET PGID on a single path.
*/
@@ -167,11 +211,14 @@
return;
out_nopath:
+ if (cdev->private->flags.pgid_unknown) {
+ /* At least one SPID could be partially done. */
+ pgid_wipeout_start(cdev);
+ return;
+ }
verify_done(cdev, sch->vpm ? 0 : -EACCES);
}
-static void verify_start(struct ccw_device *cdev);
-
/*
* Process SET PGID request result for a single path.
*/
@@ -357,6 +404,10 @@
cdev->private->pgid_todo_mask, mismatch, reserved, reset);
switch (rc) {
case 0:
+ if (cdev->private->flags.pgid_unknown) {
+ pgid_wipeout_start(cdev);
+ return;
+ }
/* Anything left to do? */
if (cdev->private->pgid_todo_mask == 0) {
verify_done(cdev, sch->vpm == 0 ? -EACCES : 0);
@@ -400,6 +451,7 @@
{
struct subchannel *sch = to_subchannel(cdev->dev.parent);
struct ccw_request *req = &cdev->private->req;
+ int ret;
req->lpm = lpm_adjust(req->lpm, sch->schib.pmcw.pam &
~cdev->private->path_noirq_mask);
@@ -410,7 +462,13 @@
return;
out_nopath:
- snid_done(cdev, cdev->private->pgid_valid_mask ? 0 : -EACCES);
+ if (cdev->private->pgid_valid_mask)
+ ret = 0;
+ else if (cdev->private->path_noirq_mask)
+ ret = -ETIME;
+ else
+ ret = -EACCES;
+ snid_done(cdev, ret);
}
/*