xref: /linux/drivers/scsi/libfc/fc_npiv.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright(c) 2009 Intel Corporation. All rights reserved.
4  *
5  * Maintained at www.Open-FCoE.org
6  */
7 
8 /*
9  * NPIV VN_Port helper functions for libfc
10  */
11 
12 #include <scsi/libfc.h>
13 #include <linux/export.h>
14 
15 /**
16  * libfc_vport_create() - Create a new NPIV vport instance
17  * @vport: fc_vport structure from scsi_transport_fc
18  * @privsize: driver private data size to allocate along with the Scsi_Host
19  */
20 
21 struct fc_lport *libfc_vport_create(struct fc_vport *vport, int privsize)
22 {
23 	struct Scsi_Host *shost = vport_to_shost(vport);
24 	struct fc_lport *n_port = shost_priv(shost);
25 	struct fc_lport *vn_port;
26 
27 	vn_port = libfc_host_alloc(shost->hostt, privsize);
28 	if (!vn_port)
29 		return vn_port;
30 
31 	vn_port->vport = vport;
32 	vport->dd_data = vn_port;
33 
34 	mutex_lock(&n_port->lp_mutex);
35 	list_add_tail(&vn_port->list, &n_port->vports);
36 	mutex_unlock(&n_port->lp_mutex);
37 
38 	return vn_port;
39 }
40 EXPORT_SYMBOL(libfc_vport_create);
41 
42 /**
43  * fc_vport_id_lookup() - find NPIV lport that matches a given fabric ID
44  * @n_port: Top level N_Port which may have multiple NPIV VN_Ports
45  * @port_id: Fabric ID to find a match for
46  *
47  * Returns: matching lport pointer or NULL if there is no match
48  */
49 struct fc_lport *fc_vport_id_lookup(struct fc_lport *n_port, u32 port_id)
50 {
51 	struct fc_lport *lport = NULL;
52 	struct fc_lport *vn_port;
53 
54 	if (n_port->port_id == port_id)
55 		return n_port;
56 
57 	if (port_id == FC_FID_FLOGI)
58 		return n_port;		/* for point-to-point */
59 
60 	mutex_lock(&n_port->lp_mutex);
61 	list_for_each_entry(vn_port, &n_port->vports, list) {
62 		if (vn_port->port_id == port_id) {
63 			lport = vn_port;
64 			break;
65 		}
66 	}
67 	mutex_unlock(&n_port->lp_mutex);
68 
69 	return lport;
70 }
71 EXPORT_SYMBOL(fc_vport_id_lookup);
72 
73 /*
74  * When setting the link state of vports during an lport state change, it's
75  * necessary to hold the lp_mutex of both the N_Port and the VN_Port.
76  * This tells the lockdep engine to treat the nested locking of the VN_Port
77  * as a different lock class.
78  */
79 enum libfc_lport_mutex_class {
80 	LPORT_MUTEX_NORMAL = 0,
81 	LPORT_MUTEX_VN_PORT = 1,
82 };
83 
84 /**
85  * __fc_vport_setlink() - update link and status on a VN_Port
86  * @n_port: parent N_Port
87  * @vn_port: VN_Port to update
88  *
89  * Locking: must be called with both the N_Port and VN_Port lp_mutex held
90  */
91 static void __fc_vport_setlink(struct fc_lport *n_port,
92 			       struct fc_lport *vn_port)
93 {
94 	struct fc_vport *vport = vn_port->vport;
95 
96 	if (vn_port->state == LPORT_ST_DISABLED)
97 		return;
98 
99 	if (n_port->state == LPORT_ST_READY) {
100 		if (n_port->npiv_enabled) {
101 			fc_vport_set_state(vport, FC_VPORT_INITIALIZING);
102 			__fc_linkup(vn_port);
103 		} else {
104 			fc_vport_set_state(vport, FC_VPORT_NO_FABRIC_SUPP);
105 			__fc_linkdown(vn_port);
106 		}
107 	} else {
108 		fc_vport_set_state(vport, FC_VPORT_LINKDOWN);
109 		__fc_linkdown(vn_port);
110 	}
111 }
112 
113 /**
114  * fc_vport_setlink() - update link and status on a VN_Port
115  * @vn_port: virtual port to update
116  */
117 void fc_vport_setlink(struct fc_lport *vn_port)
118 {
119 	struct fc_vport *vport = vn_port->vport;
120 	struct Scsi_Host *shost = vport_to_shost(vport);
121 	struct fc_lport *n_port = shost_priv(shost);
122 
123 	mutex_lock(&n_port->lp_mutex);
124 	mutex_lock_nested(&vn_port->lp_mutex, LPORT_MUTEX_VN_PORT);
125 	__fc_vport_setlink(n_port, vn_port);
126 	mutex_unlock(&vn_port->lp_mutex);
127 	mutex_unlock(&n_port->lp_mutex);
128 }
129 EXPORT_SYMBOL(fc_vport_setlink);
130 
131 /**
132  * fc_vports_linkchange() - change the link state of all vports
133  * @n_port: Parent N_Port that has changed state
134  *
135  * Locking: called with the n_port lp_mutex held
136  */
137 void fc_vports_linkchange(struct fc_lport *n_port)
138 {
139 	struct fc_lport *vn_port;
140 
141 	list_for_each_entry(vn_port, &n_port->vports, list) {
142 		mutex_lock_nested(&vn_port->lp_mutex, LPORT_MUTEX_VN_PORT);
143 		__fc_vport_setlink(n_port, vn_port);
144 		mutex_unlock(&vn_port->lp_mutex);
145 	}
146 }
147 
148