[SCSI] libfcoe: Remove mutex_trylock/restart_syscall checks

This code was incorrectly ported from fcoe.c when the
fcoe transport infrastructure was put into place. It
was originally needed in fcoe.c when dealing with
the rtnl mutex. In that code it was only needed to
avoid a lockdep false positive. In libfcoe we don't
deal with the rtnl mutex, we don't get the lockdep
false positive and therefore we don't need these
checks.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>

drivers/scsi/fcoe/fcoe_transport.c

@@ -530,9 +530,6 @@ static int fcoe_transport_create(const char *buffer, struct kernel_param *kp)
 	struct fcoe_transport *ft = NULL;
 	enum fip_state fip_mode = (enum fip_state)(long)kp->arg;
 
-	if (!mutex_trylock(&ft_mutex))
-		return restart_syscall();
-
 #ifdef CONFIG_LIBFCOE_MODULE
 	/*
 	 * Make sure the module has been initialized, and is not about to be
@@ -543,6 +540,8 @@ static int fcoe_transport_create(const char *buffer, struct kernel_param *kp)
 		goto out_nodev;
 #endif
 
+	mutex_lock(&ft_mutex);
+
 	netdev = fcoe_if_to_netdev(buffer);
 	if (!netdev) {
 		LIBFCOE_TRANSPORT_DBG("Invalid device %s.\n", buffer);
@@ -586,10 +585,7 @@ static int fcoe_transport_create(const char *buffer, struct kernel_param *kp)
 	dev_put(netdev);
 out_nodev:
 	mutex_unlock(&ft_mutex);
-	if (rc == -ERESTARTSYS)
-		return restart_syscall();
-	else
-		return rc;
+	return rc;
 }
 
 /**
@@ -608,9 +604,6 @@ static int fcoe_transport_destroy(const char *buffer, struct kernel_param *kp)
 	struct net_device *netdev = NULL;
 	struct fcoe_transport *ft = NULL;
 
-	if (!mutex_trylock(&ft_mutex))
-		return restart_syscall();
-
 #ifdef CONFIG_LIBFCOE_MODULE
 	/*
 	 * Make sure the module has been initialized, and is not about to be
@@ -621,6 +614,8 @@ static int fcoe_transport_destroy(const char *buffer, struct kernel_param *kp)
 		goto out_nodev;
 #endif
 
+	mutex_lock(&ft_mutex);
+
 	netdev = fcoe_if_to_netdev(buffer);
 	if (!netdev) {
 		LIBFCOE_TRANSPORT_DBG("invalid device %s.\n", buffer);
@@ -645,11 +640,7 @@ static int fcoe_transport_destroy(const char *buffer, struct kernel_param *kp)
 	dev_put(netdev);
 out_nodev:
 	mutex_unlock(&ft_mutex);
-
-	if (rc == -ERESTARTSYS)
-		return restart_syscall();
-	else
-		return rc;
+	return rc;
 }
 
 /**
@@ -667,9 +658,6 @@ static int fcoe_transport_disable(const char *buffer, struct kernel_param *kp)
 	struct net_device *netdev = NULL;
 	struct fcoe_transport *ft = NULL;
 
-	if (!mutex_trylock(&ft_mutex))
-		return restart_syscall();
-
 #ifdef CONFIG_LIBFCOE_MODULE
 	/*
 	 * Make sure the module has been initialized, and is not about to be
@@ -680,6 +668,8 @@ static int fcoe_transport_disable(const char *buffer, struct kernel_param *kp)
 		goto out_nodev;
 #endif
 
+	mutex_lock(&ft_mutex);
+
 	netdev = fcoe_if_to_netdev(buffer);
 	if (!netdev)
 		goto out_nodev;
@@ -716,9 +706,6 @@ static int fcoe_transport_enable(const char *buffer, struct kernel_param *kp)
 	struct net_device *netdev = NULL;
 	struct fcoe_transport *ft = NULL;
 
-	if (!mutex_trylock(&ft_mutex))
-		return restart_syscall();
-
 #ifdef CONFIG_LIBFCOE_MODULE
 	/*
 	 * Make sure the module has been initialized, and is not about to be
@@ -729,6 +716,8 @@ static int fcoe_transport_enable(const char *buffer, struct kernel_param *kp)
 		goto out_nodev;
 #endif
 
+	mutex_lock(&ft_mutex);
+
 	netdev = fcoe_if_to_netdev(buffer);
 	if (!netdev)
 		goto out_nodev;
@@ -743,10 +732,7 @@ static int fcoe_transport_enable(const char *buffer, struct kernel_param *kp)
 	dev_put(netdev);
 out_nodev:
 	mutex_unlock(&ft_mutex);
-	if (rc == -ERESTARTSYS)
-		return restart_syscall();
-	else
-		return rc;
+	return rc;
 }
 
 /**