drivers/scsi/ibmvscsi/iseries_vscsi.c

   1 /* ------------------------------------------------------------
   2  * iSeries_vscsi.c
   3  * (C) Copyright IBM Corporation 1994, 2003
   4  * Authors: Colin DeVilbiss (devilbis@us.ibm.com)
   5  *          Santiago Leon (santil@us.ibm.com)
   6  *          Dave Boutcher (sleddog@us.ibm.com)
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
  21  * USA
  22  *
  23  * ------------------------------------------------------------
  24  * iSeries-specific functions of the SCSI host adapter for Virtual I/O devices
  25  *
  26  * This driver allows the Linux SCSI peripheral drivers to directly
  27  * access devices in the hosting partition, either on an iSeries
  28  * hypervisor system or a converged hypervisor system.
  29  */
  30
  31 #include <asm/iseries/vio.h>
  32 #include <asm/iseries/hv_lp_event.h>
  33 #include <asm/iseries/hv_types.h>
  34 #include <asm/iseries/hv_lp_config.h>
  35 #include <asm/vio.h>
  36 #include <linux/device.h>
  37 #include "ibmvscsi.h"
  38
  39 /* global variables */
  40 static struct ibmvscsi_host_data *single_host_data;
  41
  42 /* ------------------------------------------------------------
  43  * Routines for direct interpartition interaction
  44  */
  45 struct srp_lp_event {
  46         struct HvLpEvent lpevt; /* 0x00-0x17          */
  47         u32 reserved1;          /* 0x18-0x1B; unused  */
  48         u16 version;            /* 0x1C-0x1D; unused  */
  49         u16 subtype_rc;         /* 0x1E-0x1F; unused  */
  50         struct viosrp_crq crq;  /* 0x20-0x3F          */
  51 };
  52
  53 /**
  54  * standard interface for handling logical partition events.
  55  */
  56 static void iseriesvscsi_handle_event(struct HvLpEvent *lpevt)
  57 {
  58         struct srp_lp_event *evt = (struct srp_lp_event *)lpevt;
  59
  60         if (!evt) {
  61                 printk(KERN_ERR "ibmvscsi: received null event\n");
  62                 return;
  63         }
  64
  65         if (single_host_data == NULL) {
  66                 printk(KERN_ERR
  67                        "ibmvscsi: received event, no adapter present\n");
  68                 return;
  69         }
  70
  71         ibmvscsi_handle_crq(&evt->crq, single_host_data);
  72 }
  73
  74 /* ------------------------------------------------------------
  75  * Routines for driver initialization
  76  */
  77 static int iseriesvscsi_init_crq_queue(struct crq_queue *queue,
  78                                        struct ibmvscsi_host_data *hostdata,
  79                                        int max_requests)
  80 {
  81         int rc;
  82
  83         single_host_data = hostdata;
  84         rc = viopath_open(viopath_hostLp, viomajorsubtype_scsi, max_requests);
  85         if (rc < 0) {
  86                 printk("viopath_open failed with rc %d in open_event_path\n",
  87                        rc);
  88                 goto viopath_open_failed;
  89         }
  90
  91         rc = vio_setHandler(viomajorsubtype_scsi, iseriesvscsi_handle_event);
  92         if (rc < 0) {
  93                 printk("vio_setHandler failed with rc %d in open_event_path\n",
  94                        rc);
  95                 goto vio_setHandler_failed;
  96         }
  97         return 0;
  98
  99       vio_setHandler_failed:
 100         viopath_close(viopath_hostLp, viomajorsubtype_scsi, max_requests);
 101       viopath_open_failed:
 102         return -1;
 103 }
 104
 105 static void iseriesvscsi_release_crq_queue(struct crq_queue *queue,
 106                                            struct ibmvscsi_host_data *hostdata,
 107                                            int max_requests)
 108 {
 109         vio_clearHandler(viomajorsubtype_scsi);
 110         viopath_close(viopath_hostLp, viomajorsubtype_scsi, max_requests);
 111 }
 112
 113 /**
 114  * reset_crq_queue: - resets a crq after a failure
 115  * @queue:      crq_queue to initialize and register
 116  * @hostdata:   ibmvscsi_host_data of host
 117  *
 118  * no-op for iSeries
 119  */
 120 static int iseriesvscsi_reset_crq_queue(struct crq_queue *queue,
 121                                         struct ibmvscsi_host_data *hostdata)
 122 {
 123         return 0;
 124 }
 125
 126 /**
 127  * reenable_crq_queue: - reenables a crq after a failure
 128  * @queue:      crq_queue to initialize and register
 129  * @hostdata:   ibmvscsi_host_data of host
 130  *
 131  * no-op for iSeries
 132  */
 133 static int iseriesvscsi_reenable_crq_queue(struct crq_queue *queue,
 134                                            struct ibmvscsi_host_data *hostdata)
 135 {
 136         return 0;
 137 }
 138
 139 /**
 140  * iseriesvscsi_send_crq: - Send a CRQ
 141  * @hostdata:   the adapter
 142  * @word1:      the first 64 bits of the data
 143  * @word2:      the second 64 bits of the data
 144  */
 145 static int iseriesvscsi_send_crq(struct ibmvscsi_host_data *hostdata,
 146                                  u64 word1, u64 word2)
 147 {
 148         single_host_data = hostdata;
 149         return HvCallEvent_signalLpEventFast(viopath_hostLp,
 150                                              HvLpEvent_Type_VirtualIo,
 151                                              viomajorsubtype_scsi,
 152                                              HvLpEvent_AckInd_NoAck,
 153                                              HvLpEvent_AckType_ImmediateAck,
 154                                              viopath_sourceinst(viopath_hostLp),
 155                                              viopath_targetinst(viopath_hostLp),
 156                                              0,
 157                                              VIOVERSION << 16, word1, word2, 0,
 158                                              0);
 159 }
 160
 161 struct ibmvscsi_ops iseriesvscsi_ops = {
 162         .init_crq_queue = iseriesvscsi_init_crq_queue,
 163         .release_crq_queue = iseriesvscsi_release_crq_queue,
 164         .reset_crq_queue = iseriesvscsi_reset_crq_queue,
 165         .reenable_crq_queue = iseriesvscsi_reenable_crq_queue,
 166         .send_crq = iseriesvscsi_send_crq,
 167 };