drivers/scsi/libfc/fc_npiv.c

   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