xref: /openbmc/linux/drivers/scsi/libfc/fc_npiv.c (revision b6dcefde)
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 
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 		goto err_out;
41 	if (fc_exch_mgr_list_clone(n_port, vn_port))
42 		goto err_put;
43 
44 	vn_port->vport = vport;
45 	vport->dd_data = vn_port;
46 
47 	mutex_lock(&n_port->lp_mutex);
48 	list_add_tail(&vn_port->list, &n_port->vports);
49 	mutex_unlock(&n_port->lp_mutex);
50 
51 	return vn_port;
52 
53 err_put:
54 	scsi_host_put(vn_port->host);
55 err_out:
56 	return NULL;
57 }
58 EXPORT_SYMBOL(libfc_vport_create);
59 
60 /**
61  * fc_vport_id_lookup() - find NPIV lport that matches a given fabric ID
62  * @n_port: Top level N_Port which may have multiple NPIV VN_Ports
63  * @port_id: Fabric ID to find a match for
64  *
65  * Returns: matching lport pointer or NULL if there is no match
66  */
67 struct fc_lport *fc_vport_id_lookup(struct fc_lport *n_port, u32 port_id)
68 {
69 	struct fc_lport *lport = NULL;
70 	struct fc_lport *vn_port;
71 
72 	if (fc_host_port_id(n_port->host) == port_id)
73 		return n_port;
74 
75 	mutex_lock(&n_port->lp_mutex);
76 	list_for_each_entry(vn_port, &n_port->vports, list) {
77 		if (fc_host_port_id(vn_port->host) == port_id) {
78 			lport = vn_port;
79 			break;
80 		}
81 	}
82 	mutex_unlock(&n_port->lp_mutex);
83 
84 	return lport;
85 }
86 
87 /*
88  * When setting the link state of vports during an lport state change, it's
89  * necessary to hold the lp_mutex of both the N_Port and the VN_Port.
90  * This tells the lockdep engine to treat the nested locking of the VN_Port
91  * as a different lock class.
92  */
93 enum libfc_lport_mutex_class {
94 	LPORT_MUTEX_NORMAL = 0,
95 	LPORT_MUTEX_VN_PORT = 1,
96 };
97 
98 /**
99  * __fc_vport_setlink() - update link and status on a VN_Port
100  * @n_port: parent N_Port
101  * @vn_port: VN_Port to update
102  *
103  * Locking: must be called with both the N_Port and VN_Port lp_mutex held
104  */
105 static void __fc_vport_setlink(struct fc_lport *n_port,
106 			       struct fc_lport *vn_port)
107 {
108 	struct fc_vport *vport = vn_port->vport;
109 
110 	if (vn_port->state == LPORT_ST_DISABLED)
111 		return;
112 
113 	if (n_port->state == LPORT_ST_READY) {
114 		if (n_port->npiv_enabled) {
115 			fc_vport_set_state(vport, FC_VPORT_INITIALIZING);
116 			__fc_linkup(vn_port);
117 		} else {
118 			fc_vport_set_state(vport, FC_VPORT_NO_FABRIC_SUPP);
119 			__fc_linkdown(vn_port);
120 		}
121 	} else {
122 		fc_vport_set_state(vport, FC_VPORT_LINKDOWN);
123 		__fc_linkdown(vn_port);
124 	}
125 }
126 
127 /**
128  * fc_vport_setlink() - update link and status on a VN_Port
129  * @vn_port: virtual port to update
130  */
131 void fc_vport_setlink(struct fc_lport *vn_port)
132 {
133 	struct fc_vport *vport = vn_port->vport;
134 	struct Scsi_Host *shost = vport_to_shost(vport);
135 	struct fc_lport *n_port = shost_priv(shost);
136 
137 	mutex_lock(&n_port->lp_mutex);
138 	mutex_lock_nested(&vn_port->lp_mutex, LPORT_MUTEX_VN_PORT);
139 	__fc_vport_setlink(n_port, vn_port);
140 	mutex_unlock(&vn_port->lp_mutex);
141 	mutex_unlock(&n_port->lp_mutex);
142 }
143 EXPORT_SYMBOL(fc_vport_setlink);
144 
145 /**
146  * fc_vports_linkchange() - change the link state of all vports
147  * @n_port: Parent N_Port that has changed state
148  *
149  * Locking: called with the n_port lp_mutex held
150  */
151 void fc_vports_linkchange(struct fc_lport *n_port)
152 {
153 	struct fc_lport *vn_port;
154 
155 	list_for_each_entry(vn_port, &n_port->vports, list) {
156 		mutex_lock_nested(&vn_port->lp_mutex, LPORT_MUTEX_VN_PORT);
157 		__fc_vport_setlink(n_port, vn_port);
158 		mutex_unlock(&vn_port->lp_mutex);
159 	}
160 }
161 
162