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-rw-r--r--Documentation/ABI/stable/sysfs-transport-srp31
-rw-r--r--drivers/scsi/scsi_transport_srp.c430
-rw-r--r--include/scsi/scsi_transport_srp.h74
3 files changed, 532 insertions, 3 deletions
diff --git a/Documentation/ABI/stable/sysfs-transport-srp b/Documentation/ABI/stable/sysfs-transport-srp
index b36fb0dc13c8..8b6acc775b71 100644
--- a/Documentation/ABI/stable/sysfs-transport-srp
+++ b/Documentation/ABI/stable/sysfs-transport-srp
@@ -5,6 +5,24 @@ Contact: linux-scsi@vger.kernel.org, linux-rdma@vger.kernel.org
Description: Instructs an SRP initiator to disconnect from a target and to
remove all LUNs imported from that target.
+What: /sys/class/srp_remote_ports/port-<h>:<n>/dev_loss_tmo
+Date: February 1, 2014
+KernelVersion: 3.13
+Contact: linux-scsi@vger.kernel.org, linux-rdma@vger.kernel.org
+Description: Number of seconds the SCSI layer will wait after a transport
+ layer error has been observed before removing a target port.
+ Zero means immediate removal. Setting this attribute to "off"
+ will disable the dev_loss timer.
+
+What: /sys/class/srp_remote_ports/port-<h>:<n>/fast_io_fail_tmo
+Date: February 1, 2014
+KernelVersion: 3.13
+Contact: linux-scsi@vger.kernel.org, linux-rdma@vger.kernel.org
+Description: Number of seconds the SCSI layer will wait after a transport
+ layer error has been observed before failing I/O. Zero means
+ failing I/O immediately. Setting this attribute to "off" will
+ disable the fast_io_fail timer.
+
What: /sys/class/srp_remote_ports/port-<h>:<n>/port_id
Date: June 27, 2007
KernelVersion: 2.6.24
@@ -17,3 +35,16 @@ Date: June 27, 2007
KernelVersion: 2.6.24
Contact: linux-scsi@vger.kernel.org
Description: Role of the remote port. Either "SRP Initiator" or "SRP Target".
+
+What: /sys/class/srp_remote_ports/port-<h>:<n>/state
+Date: February 1, 2014
+KernelVersion: 3.13
+Contact: linux-scsi@vger.kernel.org, linux-rdma@vger.kernel.org
+Description: State of the transport layer used for communication with the
+ remote port. "running" if the transport layer is operational;
+ "blocked" if a transport layer error has been encountered but
+ the fast_io_fail_tmo timer has not yet fired; "fail-fast"
+ after the fast_io_fail_tmo timer has fired and before the
+ "dev_loss_tmo" timer has fired; "lost" after the
+ "dev_loss_tmo" timer has fired and before the port is finally
+ removed.
diff --git a/drivers/scsi/scsi_transport_srp.c b/drivers/scsi/scsi_transport_srp.c
index f7ba94aa52cb..2696e26b3423 100644
--- a/drivers/scsi/scsi_transport_srp.c
+++ b/drivers/scsi/scsi_transport_srp.c
@@ -24,12 +24,15 @@
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/string.h>
+#include <linux/delay.h>
#include <scsi/scsi.h>
+#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_srp.h>
+#include "scsi_priv.h"
#include "scsi_transport_srp_internal.h"
struct srp_host_attrs {
@@ -38,7 +41,7 @@ struct srp_host_attrs {
#define to_srp_host_attrs(host) ((struct srp_host_attrs *)(host)->shost_data)
#define SRP_HOST_ATTRS 0
-#define SRP_RPORT_ATTRS 3
+#define SRP_RPORT_ATTRS 6
struct srp_internal {
struct scsi_transport_template t;
@@ -54,6 +57,34 @@ struct srp_internal {
#define dev_to_rport(d) container_of(d, struct srp_rport, dev)
#define transport_class_to_srp_rport(dev) dev_to_rport((dev)->parent)
+static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r)
+{
+ return dev_to_shost(r->dev.parent);
+}
+
+/**
+ * srp_tmo_valid() - check timeout combination validity
+ *
+ * The combination of the timeout parameters must be such that SCSI commands
+ * are finished in a reasonable time. Hence do not allow the fast I/O fail
+ * timeout to exceed SCSI_DEVICE_BLOCK_MAX_TIMEOUT. Furthermore, these
+ * parameters must be such that multipath can detect failed paths timely.
+ * Hence do not allow both parameters to be disabled simultaneously.
+ */
+int srp_tmo_valid(int fast_io_fail_tmo, int dev_loss_tmo)
+{
+ if (fast_io_fail_tmo < 0 && dev_loss_tmo < 0)
+ return -EINVAL;
+ if (fast_io_fail_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT)
+ return -EINVAL;
+ if (dev_loss_tmo >= LONG_MAX / HZ)
+ return -EINVAL;
+ if (fast_io_fail_tmo >= 0 && dev_loss_tmo >= 0 &&
+ fast_io_fail_tmo >= dev_loss_tmo)
+ return -EINVAL;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(srp_tmo_valid);
static int srp_host_setup(struct transport_container *tc, struct device *dev,
struct device *cdev)
@@ -134,10 +165,383 @@ static ssize_t store_srp_rport_delete(struct device *dev,
static DEVICE_ATTR(delete, S_IWUSR, NULL, store_srp_rport_delete);
+static ssize_t show_srp_rport_state(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ static const char *const state_name[] = {
+ [SRP_RPORT_RUNNING] = "running",
+ [SRP_RPORT_BLOCKED] = "blocked",
+ [SRP_RPORT_FAIL_FAST] = "fail-fast",
+ [SRP_RPORT_LOST] = "lost",
+ };
+ struct srp_rport *rport = transport_class_to_srp_rport(dev);
+ enum srp_rport_state state = rport->state;
+
+ return sprintf(buf, "%s\n",
+ (unsigned)state < ARRAY_SIZE(state_name) ?
+ state_name[state] : "???");
+}
+
+static DEVICE_ATTR(state, S_IRUGO, show_srp_rport_state, NULL);
+
+static ssize_t srp_show_tmo(char *buf, int tmo)
+{
+ return tmo >= 0 ? sprintf(buf, "%d\n", tmo) : sprintf(buf, "off\n");
+}
+
+static int srp_parse_tmo(int *tmo, const char *buf)
+{
+ int res = 0;
+
+ if (strncmp(buf, "off", 3) != 0)
+ res = kstrtoint(buf, 0, tmo);
+ else
+ *tmo = -1;
+
+ return res;
+}
+
+static ssize_t show_srp_rport_fast_io_fail_tmo(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct srp_rport *rport = transport_class_to_srp_rport(dev);
+
+ return srp_show_tmo(buf, rport->fast_io_fail_tmo);
+}
+
+static ssize_t store_srp_rport_fast_io_fail_tmo(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct srp_rport *rport = transport_class_to_srp_rport(dev);
+ int res;
+ int fast_io_fail_tmo;
+
+ res = srp_parse_tmo(&fast_io_fail_tmo, buf);
+ if (res)
+ goto out;
+ res = srp_tmo_valid(fast_io_fail_tmo, rport->dev_loss_tmo);
+ if (res)
+ goto out;
+ rport->fast_io_fail_tmo = fast_io_fail_tmo;
+ res = count;
+
+out:
+ return res;
+}
+
+static DEVICE_ATTR(fast_io_fail_tmo, S_IRUGO | S_IWUSR,
+ show_srp_rport_fast_io_fail_tmo,
+ store_srp_rport_fast_io_fail_tmo);
+
+static ssize_t show_srp_rport_dev_loss_tmo(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct srp_rport *rport = transport_class_to_srp_rport(dev);
+
+ return srp_show_tmo(buf, rport->dev_loss_tmo);
+}
+
+static ssize_t store_srp_rport_dev_loss_tmo(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct srp_rport *rport = transport_class_to_srp_rport(dev);
+ int res;
+ int dev_loss_tmo;
+
+ res = srp_parse_tmo(&dev_loss_tmo, buf);
+ if (res)
+ goto out;
+ res = srp_tmo_valid(rport->fast_io_fail_tmo, dev_loss_tmo);
+ if (res)
+ goto out;
+ rport->dev_loss_tmo = dev_loss_tmo;
+ res = count;
+
+out:
+ return res;
+}
+
+static DEVICE_ATTR(dev_loss_tmo, S_IRUGO | S_IWUSR,
+ show_srp_rport_dev_loss_tmo,
+ store_srp_rport_dev_loss_tmo);
+
+static int srp_rport_set_state(struct srp_rport *rport,
+ enum srp_rport_state new_state)
+{
+ enum srp_rport_state old_state = rport->state;
+
+ lockdep_assert_held(&rport->mutex);
+
+ switch (new_state) {
+ case SRP_RPORT_RUNNING:
+ switch (old_state) {
+ case SRP_RPORT_LOST:
+ goto invalid;
+ default:
+ break;
+ }
+ break;
+ case SRP_RPORT_BLOCKED:
+ switch (old_state) {
+ case SRP_RPORT_RUNNING:
+ break;
+ default:
+ goto invalid;
+ }
+ break;
+ case SRP_RPORT_FAIL_FAST:
+ switch (old_state) {
+ case SRP_RPORT_LOST:
+ goto invalid;
+ default:
+ break;
+ }
+ break;
+ case SRP_RPORT_LOST:
+ break;
+ }
+ rport->state = new_state;
+ return 0;
+
+invalid:
+ return -EINVAL;
+}
+
+static void __rport_fail_io_fast(struct srp_rport *rport)
+{
+ struct Scsi_Host *shost = rport_to_shost(rport);
+ struct srp_internal *i;
+
+ lockdep_assert_held(&rport->mutex);
+
+ if (srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST))
+ return;
+ scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE);
+
+ /* Involve the LLD if possible to terminate all I/O on the rport. */
+ i = to_srp_internal(shost->transportt);
+ if (i->f->terminate_rport_io)
+ i->f->terminate_rport_io(rport);
+}
+
+/**
+ * rport_fast_io_fail_timedout() - fast I/O failure timeout handler
+ */
+static void rport_fast_io_fail_timedout(struct work_struct *work)
+{
+ struct srp_rport *rport = container_of(to_delayed_work(work),
+ struct srp_rport, fast_io_fail_work);
+ struct Scsi_Host *shost = rport_to_shost(rport);
+
+ pr_info("fast_io_fail_tmo expired for SRP %s / %s.\n",
+ dev_name(&rport->dev), dev_name(&shost->shost_gendev));
+
+ mutex_lock(&rport->mutex);
+ if (rport->state == SRP_RPORT_BLOCKED)
+ __rport_fail_io_fast(rport);
+ mutex_unlock(&rport->mutex);
+}
+
+/**
+ * rport_dev_loss_timedout() - device loss timeout handler
+ */
+static void rport_dev_loss_timedout(struct work_struct *work)
+{
+ struct srp_rport *rport = container_of(to_delayed_work(work),
+ struct srp_rport, dev_loss_work);
+ struct Scsi_Host *shost = rport_to_shost(rport);
+ struct srp_internal *i = to_srp_internal(shost->transportt);
+
+ pr_info("dev_loss_tmo expired for SRP %s / %s.\n",
+ dev_name(&rport->dev), dev_name(&shost->shost_gendev));
+
+ mutex_lock(&rport->mutex);
+ WARN_ON(srp_rport_set_state(rport, SRP_RPORT_LOST) != 0);
+ scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE);
+ mutex_unlock(&rport->mutex);
+
+ i->f->rport_delete(rport);
+}
+
+static void __srp_start_tl_fail_timers(struct srp_rport *rport)
+{
+ struct Scsi_Host *shost = rport_to_shost(rport);
+ int fast_io_fail_tmo, dev_loss_tmo;
+
+ lockdep_assert_held(&rport->mutex);
+
+ if (!rport->deleted) {
+ fast_io_fail_tmo = rport->fast_io_fail_tmo;
+ dev_loss_tmo = rport->dev_loss_tmo;
+ pr_debug("%s current state: %d\n",
+ dev_name(&shost->shost_gendev), rport->state);
+
+ if (fast_io_fail_tmo >= 0 &&
+ srp_rport_set_state(rport, SRP_RPORT_BLOCKED) == 0) {
+ pr_debug("%s new state: %d\n",
+ dev_name(&shost->shost_gendev),
+ rport->state);
+ scsi_target_block(&shost->shost_gendev);
+ queue_delayed_work(system_long_wq,
+ &rport->fast_io_fail_work,
+ 1UL * fast_io_fail_tmo * HZ);
+ }
+ if (dev_loss_tmo >= 0)
+ queue_delayed_work(system_long_wq,
+ &rport->dev_loss_work,
+ 1UL * dev_loss_tmo * HZ);
+ } else {
+ pr_debug("%s has already been deleted\n",
+ dev_name(&shost->shost_gendev));
+ srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST);
+ scsi_target_unblock(&shost->shost_gendev,
+ SDEV_TRANSPORT_OFFLINE);
+ }
+}
+
+/**
+ * srp_start_tl_fail_timers() - start the transport layer failure timers
+ *
+ * Start the transport layer fast I/O failure and device loss timers. Do not
+ * modify a timer that was already started.
+ */
+void srp_start_tl_fail_timers(struct srp_rport *rport)
+{
+ mutex_lock(&rport->mutex);
+ __srp_start_tl_fail_timers(rport);
+ mutex_unlock(&rport->mutex);
+}
+EXPORT_SYMBOL(srp_start_tl_fail_timers);
+
+/**
+ * scsi_request_fn_active() - number of kernel threads inside scsi_request_fn()
+ */
+static int scsi_request_fn_active(struct Scsi_Host *shost)
+{
+ struct scsi_device *sdev;
+ struct request_queue *q;
+ int request_fn_active = 0;
+
+ shost_for_each_device(sdev, shost) {
+ q = sdev->request_queue;
+
+ spin_lock_irq(q->queue_lock);
+ request_fn_active += q->request_fn_active;
+ spin_unlock_irq(q->queue_lock);
+ }
+
+ return request_fn_active;
+}
+
+/**
+ * srp_reconnect_rport() - reconnect to an SRP target port
+ *
+ * Blocks SCSI command queueing before invoking reconnect() such that
+ * queuecommand() won't be invoked concurrently with reconnect() from outside
+ * the SCSI EH. This is important since a reconnect() implementation may
+ * reallocate resources needed by queuecommand().
+ *
+ * Notes:
+ * - This function neither waits until outstanding requests have finished nor
+ * tries to abort these. It is the responsibility of the reconnect()
+ * function to finish outstanding commands before reconnecting to the target
+ * port.
+ * - It is the responsibility of the caller to ensure that the resources
+ * reallocated by the reconnect() function won't be used while this function
+ * is in progress. One possible strategy is to invoke this function from
+ * the context of the SCSI EH thread only. Another possible strategy is to
+ * lock the rport mutex inside each SCSI LLD callback that can be invoked by
+ * the SCSI EH (the scsi_host_template.eh_*() functions and also the
+ * scsi_host_template.queuecommand() function).
+ */
+int srp_reconnect_rport(struct srp_rport *rport)
+{
+ struct Scsi_Host *shost = rport_to_shost(rport);
+ struct srp_internal *i = to_srp_internal(shost->transportt);
+ struct scsi_device *sdev;
+ int res;
+
+ pr_debug("SCSI host %s\n", dev_name(&shost->shost_gendev));
+
+ res = mutex_lock_interruptible(&rport->mutex);
+ if (res)
+ goto out;
+ scsi_target_block(&shost->shost_gendev);
+ while (scsi_request_fn_active(shost))
+ msleep(20);
+ res = i->f->reconnect(rport);
+ pr_debug("%s (state %d): transport.reconnect() returned %d\n",
+ dev_name(&shost->shost_gendev), rport->state, res);
+ if (res == 0) {
+ cancel_delayed_work(&rport->fast_io_fail_work);
+ cancel_delayed_work(&rport->dev_loss_work);
+
+ srp_rport_set_state(rport, SRP_RPORT_RUNNING);
+ scsi_target_unblock(&shost->shost_gendev, SDEV_RUNNING);
+ /*
+ * If the SCSI error handler has offlined one or more devices,
+ * invoking scsi_target_unblock() won't change the state of
+ * these devices into running so do that explicitly.
+ */
+ spin_lock_irq(shost->host_lock);
+ __shost_for_each_device(sdev, shost)
+ if (sdev->sdev_state == SDEV_OFFLINE)
+ sdev->sdev_state = SDEV_RUNNING;
+ spin_unlock_irq(shost->host_lock);
+ } else if (rport->state == SRP_RPORT_RUNNING) {
+ /*
+ * srp_reconnect_rport() was invoked with fast_io_fail
+ * off. Mark the port as failed and start the TL failure
+ * timers if these had not yet been started.
+ */
+ __rport_fail_io_fast(rport);
+ scsi_target_unblock(&shost->shost_gendev,
+ SDEV_TRANSPORT_OFFLINE);
+ __srp_start_tl_fail_timers(rport);
+ } else if (rport->state != SRP_RPORT_BLOCKED) {
+ scsi_target_unblock(&shost->shost_gendev,
+ SDEV_TRANSPORT_OFFLINE);
+ }
+ mutex_unlock(&rport->mutex);
+
+out:
+ return res;
+}
+EXPORT_SYMBOL(srp_reconnect_rport);
+
+/**
+ * srp_timed_out() - SRP transport intercept of the SCSI timeout EH
+ *
+ * If a timeout occurs while an rport is in the blocked state, ask the SCSI
+ * EH to continue waiting (BLK_EH_RESET_TIMER). Otherwise let the SCSI core
+ * handle the timeout (BLK_EH_NOT_HANDLED).
+ *
+ * Note: This function is called from soft-IRQ context and with the request
+ * queue lock held.
+ */
+static enum blk_eh_timer_return srp_timed_out(struct scsi_cmnd *scmd)
+{
+ struct scsi_device *sdev = scmd->device;
+ struct Scsi_Host *shost = sdev->host;
+ struct srp_internal *i = to_srp_internal(shost->transportt);
+
+ pr_debug("timeout for sdev %s\n", dev_name(&sdev->sdev_gendev));
+ return i->f->reset_timer_if_blocked && scsi_device_blocked(sdev) ?
+ BLK_EH_RESET_TIMER : BLK_EH_NOT_HANDLED;
+}
+
static void srp_rport_release(struct device *dev)
{
struct srp_rport *rport = dev_to_rport(dev);
+ cancel_delayed_work_sync(&rport->fast_io_fail_work);
+ cancel_delayed_work_sync(&rport->dev_loss_work);
+
put_device(dev->parent);
kfree(rport);
}
@@ -214,12 +618,15 @@ struct srp_rport *srp_rport_add(struct Scsi_Host *shost,
{
struct srp_rport *rport;
struct device *parent = &shost->shost_gendev;
+ struct srp_internal *i = to_srp_internal(shost->transportt);
int id, ret;
rport = kzalloc(sizeof(*rport), GFP_KERNEL);
if (!rport)
return ERR_PTR(-ENOMEM);
+ mutex_init(&rport->mutex);
+
device_initialize(&rport->dev);
rport->dev.parent = get_device(parent);
@@ -228,6 +635,13 @@ struct srp_rport *srp_rport_add(struct Scsi_Host *shost,
memcpy(rport->port_id, ids->port_id, sizeof(rport->port_id));
rport->roles = ids->roles;
+ rport->fast_io_fail_tmo = i->f->fast_io_fail_tmo ?
+ *i->f->fast_io_fail_tmo : 15;
+ rport->dev_loss_tmo = i->f->dev_loss_tmo ? *i->f->dev_loss_tmo : 60;
+ INIT_DELAYED_WORK(&rport->fast_io_fail_work,
+ rport_fast_io_fail_timedout);
+ INIT_DELAYED_WORK(&rport->dev_loss_work, rport_dev_loss_timedout);
+
id = atomic_inc_return(&to_srp_host_attrs(shost)->next_port_id);
dev_set_name(&rport->dev, "port-%d:%d", shost->host_no, id);
@@ -277,6 +691,13 @@ void srp_rport_del(struct srp_rport *rport)
transport_remove_device(dev);
device_del(dev);
transport_destroy_device(dev);
+
+ mutex_lock(&rport->mutex);
+ if (rport->state == SRP_RPORT_BLOCKED)
+ __rport_fail_io_fast(rport);
+ rport->deleted = true;
+ mutex_unlock(&rport->mutex);
+
put_device(dev);
}
EXPORT_SYMBOL_GPL(srp_rport_del);
@@ -328,6 +749,8 @@ srp_attach_transport(struct srp_function_template *ft)
if (!i)
return NULL;
+ i->t.eh_timed_out = srp_timed_out;
+
i->t.tsk_mgmt_response = srp_tsk_mgmt_response;
i->t.it_nexus_response = srp_it_nexus_response;
@@ -345,6 +768,11 @@ srp_attach_transport(struct srp_function_template *ft)
count = 0;
i->rport_attrs[count++] = &dev_attr_port_id;
i->rport_attrs[count++] = &dev_attr_roles;
+ if (ft->has_rport_state) {
+ i->rport_attrs[count++] = &dev_attr_state;
+ i->rport_attrs[count++] = &dev_attr_fast_io_fail_tmo;
+ i->rport_attrs[count++] = &dev_attr_dev_loss_tmo;
+ }
if (ft->rport_delete)
i->rport_attrs[count++] = &dev_attr_delete;
i->rport_attrs[count++] = NULL;
diff --git a/include/scsi/scsi_transport_srp.h b/include/scsi/scsi_transport_srp.h
index 5a2d2d1081c1..ee7001677f64 100644
--- a/include/scsi/scsi_transport_srp.h
+++ b/include/scsi/scsi_transport_srp.h
@@ -13,6 +13,26 @@ struct srp_rport_identifiers {
u8 roles;
};
+/**
+ * enum srp_rport_state - SRP transport layer state
+ * @SRP_RPORT_RUNNING: Transport layer operational.
+ * @SRP_RPORT_BLOCKED: Transport layer not operational; fast I/O fail timer
+ * is running and I/O has been blocked.
+ * @SRP_RPORT_FAIL_FAST: Fast I/O fail timer has expired; fail I/O fast.
+ * @SRP_RPORT_LOST: Device loss timer has expired; port is being removed.
+ */
+enum srp_rport_state {
+ SRP_RPORT_RUNNING,
+ SRP_RPORT_BLOCKED,
+ SRP_RPORT_FAIL_FAST,
+ SRP_RPORT_LOST,
+};
+
+/**
+ * struct srp_rport
+ * @lld_data: LLD private data.
+ * @mutex: Protects against concurrent rport fast_io_fail / dev_loss_tmo.
+ */
struct srp_rport {
/* for initiator and target drivers */
@@ -23,11 +43,38 @@ struct srp_rport {
/* for initiator drivers */
- void *lld_data; /* LLD private data */
+ void *lld_data;
+
+ struct mutex mutex;
+ enum srp_rport_state state;
+ bool deleted;
+ int fast_io_fail_tmo;
+ int dev_loss_tmo;
+ struct delayed_work fast_io_fail_work;
+ struct delayed_work dev_loss_work;
};
+/**
+ * struct srp_function_template
+ * @has_rport_state: Whether or not to create the state, fast_io_fail_tmo and
+ * dev_loss_tmo sysfs attribute for an rport.
+ * @reset_timer_if_blocked: Whether or srp_timed_out() should reset the command
+ * timer if the device on which it has been queued is blocked.
+ * @fast_io_fail_tmo: If not NULL, points to the default fast_io_fail_tmo value.
+ * @dev_loss_tmo: If not NULL, points to the default dev_loss_tmo value.
+ * @reconnect: Callback function for reconnecting to the target. See also
+ * srp_reconnect_rport().
+ * @terminate_rport_io: Callback function for terminating all outstanding I/O
+ * requests for an rport.
+ */
struct srp_function_template {
/* for initiator drivers */
+ bool has_rport_state;
+ bool reset_timer_if_blocked;
+ int *fast_io_fail_tmo;
+ int *dev_loss_tmo;
+ int (*reconnect)(struct srp_rport *rport);
+ void (*terminate_rport_io)(struct srp_rport *rport);
void (*rport_delete)(struct srp_rport *rport);
/* for target drivers */
int (* tsk_mgmt_response)(struct Scsi_Host *, u64, u64, int);
@@ -43,7 +90,30 @@ extern void srp_rport_put(struct srp_rport *rport);
extern struct srp_rport *srp_rport_add(struct Scsi_Host *,
struct srp_rport_identifiers *);
extern void srp_rport_del(struct srp_rport *);
-
+extern int srp_tmo_valid(int fast_io_fail_tmo, int dev_loss_tmo);
+extern int srp_reconnect_rport(struct srp_rport *rport);
+extern void srp_start_tl_fail_timers(struct srp_rport *rport);
extern void srp_remove_host(struct Scsi_Host *);
+/**
+ * srp_chkready() - evaluate the transport layer state before I/O
+ *
+ * Returns a SCSI result code that can be returned by the LLD queuecommand()
+ * implementation. The role of this function is similar to that of
+ * fc_remote_port_chkready().
+ */
+static inline int srp_chkready(struct srp_rport *rport)
+{
+ switch (rport->state) {
+ case SRP_RPORT_RUNNING:
+ case SRP_RPORT_BLOCKED:
+ default:
+ return 0;
+ case SRP_RPORT_FAIL_FAST:
+ return DID_TRANSPORT_FAILFAST << 16;
+ case SRP_RPORT_LOST:
+ return DID_NO_CONNECT << 16;
+ }
+}
+
#endif
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