1 /*
2  * Copyright(c) 2009 Intel Corporation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, write to the Free Software Foundation, Inc.,
15  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
16  *
17  * Maintained at www.Open-FCoE.org
18  */
19 
20 /*
21  * NPIV VN_Port helper functions for libfc
22  */
23 
24 #include <scsi/libfc.h>
25 
26 /**
27  * fc_vport_create() - Create a new NPIV vport instance
28  * @vport: fc_vport structure from scsi_transport_fc
29  * @privsize: driver private data size to allocate along with the Scsi_Host
30  */
31 
libfc_vport_create(struct fc_vport * vport,int privsize)32 struct fc_lport *libfc_vport_create(struct fc_vport *vport, int privsize)
33 {
34 	struct Scsi_Host *shost = vport_to_shost(vport);
35 	struct fc_lport *n_port = shost_priv(shost);
36 	struct fc_lport *vn_port;
37 
38 	vn_port = libfc_host_alloc(shost->hostt, privsize);
39 	if (!vn_port)
40 		return vn_port;
41 
42 	vn_port->vport = vport;
43 	vport->dd_data = vn_port;
44 
45 	mutex_lock(&n_port->lp_mutex);
46 	list_add_tail(&vn_port->list, &n_port->vports);
47 	mutex_unlock(&n_port->lp_mutex);
48 
49 	return vn_port;
50 }
51 EXPORT_SYMBOL(libfc_vport_create);
52 
53 /**
54  * fc_vport_id_lookup() - find NPIV lport that matches a given fabric ID
55  * @n_port: Top level N_Port which may have multiple NPIV VN_Ports
56  * @port_id: Fabric ID to find a match for
57  *
58  * Returns: matching lport pointer or NULL if there is no match
59  */
fc_vport_id_lookup(struct fc_lport * n_port,u32 port_id)60 struct fc_lport *fc_vport_id_lookup(struct fc_lport *n_port, u32 port_id)
61 {
62 	struct fc_lport *lport = NULL;
63 	struct fc_lport *vn_port;
64 
65 	if (n_port->port_id == port_id)
66 		return n_port;
67 
68 	if (port_id == FC_FID_FLOGI)
69 		return n_port;		/* for point-to-point */
70 
71 	mutex_lock(&n_port->lp_mutex);
72 	list_for_each_entry(vn_port, &n_port->vports, list) {
73 		if (vn_port->port_id == port_id) {
74 			lport = vn_port;
75 			break;
76 		}
77 	}
78 	mutex_unlock(&n_port->lp_mutex);
79 
80 	return lport;
81 }
82 EXPORT_SYMBOL(fc_vport_id_lookup);
83 
84 /*
85  * When setting the link state of vports during an lport state change, it's
86  * necessary to hold the lp_mutex of both the N_Port and the VN_Port.
87  * This tells the lockdep engine to treat the nested locking of the VN_Port
88  * as a different lock class.
89  */
90 enum libfc_lport_mutex_class {
91 	LPORT_MUTEX_NORMAL = 0,
92 	LPORT_MUTEX_VN_PORT = 1,
93 };
94 
95 /**
96  * __fc_vport_setlink() - update link and status on a VN_Port
97  * @n_port: parent N_Port
98  * @vn_port: VN_Port to update
99  *
100  * Locking: must be called with both the N_Port and VN_Port lp_mutex held
101  */
__fc_vport_setlink(struct fc_lport * n_port,struct fc_lport * vn_port)102 static void __fc_vport_setlink(struct fc_lport *n_port,
103 			       struct fc_lport *vn_port)
104 {
105 	struct fc_vport *vport = vn_port->vport;
106 
107 	if (vn_port->state == LPORT_ST_DISABLED)
108 		return;
109 
110 	if (n_port->state == LPORT_ST_READY) {
111 		if (n_port->npiv_enabled) {
112 			fc_vport_set_state(vport, FC_VPORT_INITIALIZING);
113 			__fc_linkup(vn_port);
114 		} else {
115 			fc_vport_set_state(vport, FC_VPORT_NO_FABRIC_SUPP);
116 			__fc_linkdown(vn_port);
117 		}
118 	} else {
119 		fc_vport_set_state(vport, FC_VPORT_LINKDOWN);
120 		__fc_linkdown(vn_port);
121 	}
122 }
123 
124 /**
125  * fc_vport_setlink() - update link and status on a VN_Port
126  * @vn_port: virtual port to update
127  */
fc_vport_setlink(struct fc_lport * vn_port)128 void fc_vport_setlink(struct fc_lport *vn_port)
129 {
130 	struct fc_vport *vport = vn_port->vport;
131 	struct Scsi_Host *shost = vport_to_shost(vport);
132 	struct fc_lport *n_port = shost_priv(shost);
133 
134 	mutex_lock(&n_port->lp_mutex);
135 	mutex_lock_nested(&vn_port->lp_mutex, LPORT_MUTEX_VN_PORT);
136 	__fc_vport_setlink(n_port, vn_port);
137 	mutex_unlock(&vn_port->lp_mutex);
138 	mutex_unlock(&n_port->lp_mutex);
139 }
140 EXPORT_SYMBOL(fc_vport_setlink);
141 
142 /**
143  * fc_vports_linkchange() - change the link state of all vports
144  * @n_port: Parent N_Port that has changed state
145  *
146  * Locking: called with the n_port lp_mutex held
147  */
fc_vports_linkchange(struct fc_lport * n_port)148 void fc_vports_linkchange(struct fc_lport *n_port)
149 {
150 	struct fc_lport *vn_port;
151 
152 	list_for_each_entry(vn_port, &n_port->vports, list) {
153 		mutex_lock_nested(&vn_port->lp_mutex, LPORT_MUTEX_VN_PORT);
154 		__fc_vport_setlink(n_port, vn_port);
155 		mutex_unlock(&vn_port->lp_mutex);
156 	}
157 }
158 
159