From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Leech Subject: [PATCH] iSCSI: let session recovery_tmo sysfs writes persist across recovery Date: Tue, 16 Jun 2015 16:07:13 -0700 Message-ID: <1434496033-4601-1-git-send-email-cleech@redhat.com> Reply-To: open-iscsi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , To: linux-scsi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, open-iscsi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org List-Id: linux-scsi@vger.kernel.org The iSCSI session recovery_tmo setting is writeable in sysfs, but it's also set every time a connection is established when parameters are set from iscsid over netlink. That results in the timeout being reset to the default value after every recovery. The DM multipath tools want to use the sysfs interface to lower the default timeout when there are multiple paths to fail over. It has caused confusion that we have a writeable sysfs value that seem to keep resetting itself. This patch adds an in-kernel flag that gets set once a sysfs write occurs, and then ignores netlink parameter setting once it's been modified via the sysfs interface. My thinking here is that the sysfs interface is much simpler for external tools to influence the session timeout, but if we're going to allow it to be modified directly we should ensure that setting is maintained. Signed-off-by: Chris Leech --- drivers/scsi/scsi_transport_iscsi.c | 11 ++++++++--- include/scsi/scsi_transport_iscsi.h | 1 + 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c index 67d43e3..35ef55f 100644 --- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -2040,6 +2040,7 @@ iscsi_alloc_session(struct Scsi_Host *shost, struct iscsi_transport *transport, session->transport = transport; session->creator = -1; session->recovery_tmo = 120; + session->recovery_tmo_sysfs_override = false; session->state = ISCSI_SESSION_FREE; INIT_DELAYED_WORK(&session->recovery_work, session_recovery_timedout); INIT_LIST_HEAD(&session->sess_list); @@ -2784,7 +2785,8 @@ iscsi_set_param(struct iscsi_transport *transport, struct iscsi_uevent *ev) switch (ev->u.set_param.param) { case ISCSI_PARAM_SESS_RECOVERY_TMO: sscanf(data, "%d", &value); - session->recovery_tmo = value; + if (!session->recovery_tmo_sysfs_override) + session->recovery_tmo = value; break; default: err = transport->set_param(conn, ev->u.set_param.param, @@ -4047,13 +4049,15 @@ store_priv_session_##field(struct device *dev, \ if ((session->state == ISCSI_SESSION_FREE) || \ (session->state == ISCSI_SESSION_FAILED)) \ return -EBUSY; \ - if (strncmp(buf, "off", 3) == 0) \ + if (strncmp(buf, "off", 3) == 0) { \ session->field = -1; \ - else { \ + session->field##_sysfs_override = true; \ + } else { \ val = simple_strtoul(buf, &cp, 0); \ if (*cp != '\0' && *cp != '\n') \ return -EINVAL; \ session->field = val; \ + session->field##_sysfs_override = true; \ } \ return count; \ } @@ -4064,6 +4068,7 @@ store_priv_session_##field(struct device *dev, \ static ISCSI_CLASS_ATTR(priv_sess, field, S_IRUGO | S_IWUSR, \ show_priv_session_##field, \ store_priv_session_##field) + iscsi_priv_session_rw_attr(recovery_tmo, "%d"); static struct attribute *iscsi_session_attrs[] = { diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h index 2555ee5..6183d20 100644 --- a/include/scsi/scsi_transport_iscsi.h +++ b/include/scsi/scsi_transport_iscsi.h @@ -241,6 +241,7 @@ struct iscsi_cls_session { /* recovery fields */ int recovery_tmo; + bool recovery_tmo_sysfs_override; struct delayed_work recovery_work; unsigned int target_id; -- 2.1.0 -- You received this message because you are subscribed to the Google Groups "open-iscsi" group. To unsubscribe from this group and stop receiving emails from it, send an email to open-iscsi+unsubscribe-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org To post to this group, send email to open-iscsi-/JYPxA39Uh5TLH3MbocFF+G/Ez6ZCGd0@public.gmane.org Visit this group at http://groups.google.com/group/open-iscsi. For more options, visit https://groups.google.com/d/optout.