Enable reconnect_delay, fast_io_fail_tmo and dev_loss_tmo
functionality for the IB SRP initiator. Add kernel module
parameters that allow to specify default values for these
three parameters.
Signed-off-by: Bart Van Assche <bvanass...@acm.org>
Acked-by: David Dillow <dillo...@ornl.gov>
Cc: Roland Dreier <rol...@kernel.org>
Cc: Vu Pham <v...@mellanox.com>
Cc: Sebastian Riemer <sebastian.rie...@profitbricks.com>
---
drivers/infiniband/ulp/srp/ib_srp.c | 129 +++++++++++++++++++++++++----------
drivers/infiniband/ulp/srp/ib_srp.h | 1 -
2 files changed, 94 insertions(+), 36 deletions(-)
diff --git a/drivers/infiniband/ulp/srp/ib_srp.c
b/drivers/infiniband/ulp/srp/ib_srp.c
index 37dd3fb..a7fa7ed 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.c
+++ b/drivers/infiniband/ulp/srp/ib_srp.c
@@ -86,6 +86,32 @@ module_param(topspin_workarounds, int, 0444);
MODULE_PARM_DESC(topspin_workarounds,
"Enable workarounds for Topspin/Cisco SRP target bugs if !=
0");
+static struct kernel_param_ops srp_tmo_ops;
+
+static int srp_reconnect_delay = 10;
+module_param_cb(reconnect_delay, &srp_tmo_ops, &srp_reconnect_delay,
+ S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(reconnect_delay, "Time between successive reconnect
attempts");
+
+static int srp_fast_io_fail_tmo = 15;
+module_param_cb(fast_io_fail_tmo, &srp_tmo_ops, &srp_fast_io_fail_tmo,
+ S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(fast_io_fail_tmo,
+ "Number of seconds between the observation of a transport"
+ " layer error and failing all I/O. \"off\" means that this"
+ " functionality is disabled.");
+
+static int srp_dev_loss_tmo = 600;
+module_param_cb(dev_loss_tmo, &srp_tmo_ops, &srp_dev_loss_tmo,
+ S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(dev_loss_tmo,
+ "Maximum number of seconds that the SRP transport should"
+ " insulate transport layer errors. After this time has been"
+ " exceeded the SCSI target is removed. Should be"
+ " between 1 and " __stringify(SCSI_DEVICE_BLOCK_MAX_TIMEOUT)
+ " if fast_io_fail_tmo has not been set. \"off\" means that"
+ " this functionality is disabled.");
+
static void srp_add_one(struct ib_device *device);
static void srp_remove_one(struct ib_device *device);
static void srp_recv_completion(struct ib_cq *cq, void *target_ptr);
@@ -102,6 +128,48 @@ static struct ib_client srp_client = {
static struct ib_sa_client srp_sa_client;
+static int srp_tmo_get(char *buffer, const struct kernel_param *kp)
+{
+ int tmo = *(int *)kp->arg;
+
+ if (tmo >= 0)
+ return sprintf(buffer, "%d", tmo);
+ else
+ return sprintf(buffer, "off");
+}
+
+static int srp_tmo_set(const char *val, const struct kernel_param *kp)
+{
+ int tmo, res;
+
+ if (strncmp(val, "off", 3) != 0) {
+ res = kstrtoint(val, 0, &tmo);
+ if (res)
+ goto out;
+ } else {
+ tmo = -1;
+ }
+ if (kp->arg == &srp_reconnect_delay)
+ res = srp_tmo_valid(tmo, srp_fast_io_fail_tmo,
+ srp_dev_loss_tmo);
+ else if (kp->arg == &srp_fast_io_fail_tmo)
+ res = srp_tmo_valid(srp_reconnect_delay, tmo, srp_dev_loss_tmo);
+ else
+ res = srp_tmo_valid(srp_reconnect_delay, srp_fast_io_fail_tmo,
+ tmo);
+ if (res)
+ goto out;
+ *(int *)kp->arg = tmo;
+
+out:
+ return res;
+}
+
+static struct kernel_param_ops srp_tmo_ops = {
+ .get = srp_tmo_get,
+ .set = srp_tmo_set,
+};
+
static inline struct srp_target_port *host_to_target(struct Scsi_Host *host)
{
return (struct srp_target_port *) host->hostdata;
@@ -711,13 +779,20 @@ static void srp_terminate_io(struct srp_rport *rport)
}
}
-static int srp_reconnect_target(struct srp_target_port *target)
+/*
+ * It is up to the caller to ensure that srp_rport_reconnect() calls are
+ * serialized and that no concurrent srp_queuecommand(), srp_abort(),
+ * srp_reset_device() or srp_reset_host() calls will occur while this function
+ * is in progress. One way to realize that is not to call this function
+ * directly but to call srp_reconnect_rport() instead since that last function
+ * serializes calls of this function via rport->mutex and also blocks
+ * srp_queuecommand() calls before invoking this function.
+ */
+static int srp_rport_reconnect(struct srp_rport *rport)
{
- struct Scsi_Host *shost = target->scsi_host;
+ struct srp_target_port *target = rport->lld_data;
int i, ret;
- scsi_target_block(&shost->shost_gendev);
-
srp_disconnect_target(target);
/*
* Now get a new local CM ID so that we avoid confusing the target in
@@ -747,28 +822,9 @@ static int srp_reconnect_target(struct srp_target_port
*target)
if (ret == 0)
ret = srp_connect_target(target);
- scsi_target_unblock(&shost->shost_gendev, ret == 0 ? SDEV_RUNNING :
- SDEV_TRANSPORT_OFFLINE);
- target->transport_offline = !!ret;
-
- if (ret)
- goto err;
-
- shost_printk(KERN_INFO, target->scsi_host, PFX "reconnect succeeded\n");
-
- return ret;
-
-err:
- shost_printk(KERN_ERR, target->scsi_host,
- PFX "reconnect failed (%d), removing target port.\n", ret);
-
- /*
- * We couldn't reconnect, so kill our target port off.
- * However, we have to defer the real removal because we
- * are in the context of the SCSI error handler now, which
- * will deadlock if we call scsi_remove_host().
- */
- srp_queue_remove_work(target);
+ if (ret == 0)
+ shost_printk(KERN_INFO, target->scsi_host,
+ PFX "reconnect succeeded\n");
return ret;
}
@@ -1367,10 +1423,11 @@ static int srp_queuecommand(struct Scsi_Host *shost,
struct scsi_cmnd *scmnd)
struct srp_cmd *cmd;
struct ib_device *dev;
unsigned long flags;
- int len;
+ int len, result;
- if (unlikely(target->transport_offline)) {
- scmnd->result = DID_NO_CONNECT << 16;
+ result = srp_chkready(target->rport);
+ if (unlikely(result)) {
+ scmnd->result = result;
scmnd->scsi_done(scmnd);
return 0;
}
@@ -1768,7 +1825,7 @@ static int srp_abort(struct scsi_cmnd *scmnd)
if (srp_send_tsk_mgmt(target, req->index, scmnd->device->lun,
SRP_TSK_ABORT_TASK) == 0)
ret = SUCCESS;
- else if (target->transport_offline)
+ else if (target->rport->state == SRP_RPORT_LOST)
ret = FAST_IO_FAIL;
else
ret = FAILED;
@@ -1804,14 +1861,10 @@ static int srp_reset_device(struct scsi_cmnd *scmnd)
static int srp_reset_host(struct scsi_cmnd *scmnd)
{
struct srp_target_port *target = host_to_target(scmnd->device->host);
- int ret = FAILED;
shost_printk(KERN_ERR, target->scsi_host, PFX "SRP reset_host
called\n");
- if (!srp_reconnect_target(target))
- ret = SUCCESS;
-
- return ret;
+ return srp_reconnect_rport(target->rport) == 0 ? SUCCESS : FAILED;
}
static int srp_slave_configure(struct scsi_device *sdev)
@@ -2626,6 +2679,12 @@ static void srp_remove_one(struct ib_device *device)
}
static struct srp_function_template ib_srp_transport_functions = {
+ .has_rport_state = true,
+ .reset_timer_if_blocked = true,
+ .reconnect_delay = &srp_reconnect_delay,
+ .fast_io_fail_tmo = &srp_fast_io_fail_tmo,
+ .dev_loss_tmo = &srp_dev_loss_tmo,
+ .reconnect = srp_rport_reconnect,
.rport_delete = srp_rport_delete,
.terminate_rport_io = srp_terminate_io,
};
diff --git a/drivers/infiniband/ulp/srp/ib_srp.h
b/drivers/infiniband/ulp/srp/ib_srp.h
index 02392f5..b62a943 100644
--- a/drivers/infiniband/ulp/srp/ib_srp.h
+++ b/drivers/infiniband/ulp/srp/ib_srp.h
@@ -140,7 +140,6 @@ struct srp_target_port {
unsigned int cmd_sg_cnt;
unsigned int indirect_size;
bool allow_ext_sg;
- bool transport_offline;
/* Everything above this point is used in the hot path of
* command processing. Try to keep them packed into cachelines.
--
1.7.10.4
--
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