firewire: fw-sbp2: implement nonexclusive login
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
diff --git a/drivers/firewire/fw-sbp2.c b/drivers/firewire/fw-sbp2.c
index 846aad8..2c39f19 100644
--- a/drivers/firewire/fw-sbp2.c
+++ b/drivers/firewire/fw-sbp2.c
@@ -30,6 +30,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/moduleparam.h>
#include <linux/mod_devicetable.h>
#include <linux/device.h>
#include <linux/scatterlist.h>
@@ -47,6 +48,18 @@
#include "fw-topology.h"
#include "fw-device.h"
+/*
+ * So far only bridges from Oxford Semiconductor are known to support
+ * concurrent logins. Depending on firmware, four or two concurrent logins
+ * are possible on OXFW911 and newer Oxsemi bridges.
+ *
+ * Concurrent logins are useful together with cluster filesystems.
+ */
+static int sbp2_param_exclusive_login = 1;
+module_param_named(exclusive_login, sbp2_param_exclusive_login, bool, 0644);
+MODULE_PARM_DESC(exclusive_login, "Exclusive login to sbp2 device "
+ "(default = Y, use N for concurrent initiators)");
+
/* I don't know why the SCSI stack doesn't define something like this... */
typedef void (*scsi_done_fn_t)(struct scsi_cmnd *);
@@ -155,7 +168,7 @@
#define MANAGEMENT_ORB_LUN(v) ((v))
#define MANAGEMENT_ORB_FUNCTION(v) ((v) << 16)
#define MANAGEMENT_ORB_RECONNECT(v) ((v) << 20)
-#define MANAGEMENT_ORB_EXCLUSIVE ((1) << 28)
+#define MANAGEMENT_ORB_EXCLUSIVE(v) ((v) ? 1 << 28 : 0)
#define MANAGEMENT_ORB_REQUEST_FORMAT(v) ((v) << 29)
#define MANAGEMENT_ORB_NOTIFY ((1) << 31)
@@ -431,14 +444,9 @@
orb->request.status_fifo.high = sd->address_handler.offset >> 32;
orb->request.status_fifo.low = sd->address_handler.offset;
- /*
- * FIXME: Yeah, ok this isn't elegant, we hardwire exclusive
- * login and 1 second reconnect time. The reconnect setting
- * is probably fine, but the exclusive login should be an option.
- */
if (function == SBP2_LOGIN_REQUEST) {
orb->request.misc |=
- MANAGEMENT_ORB_EXCLUSIVE |
+ MANAGEMENT_ORB_EXCLUSIVE(sbp2_param_exclusive_login) |
MANAGEMENT_ORB_RECONNECT(0);
}