drivers/staging/hv/storvsc.c

   1 /*
   2  * Copyright (c) 2009, Microsoft Corporation.
   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., 59 Temple
  15  * Place - Suite 330, Boston, MA 02111-1307 USA.
  16  *
  17  * Authors:
  18  *   Haiyang Zhang <haiyangz@microsoft.com>
  19  *   Hank Janssen  <hjanssen@microsoft.com>
  20  *   K. Y. Srinivasan <kys@microsoft.com>
  21  *
  22  */
  23 #include <linux/kernel.h>
  24 #include <linux/sched.h>
  25 #include <linux/completion.h>
  26 #include <linux/string.h>
  27 #include <linux/slab.h>
  28 #include <linux/mm.h>
  29 #include <linux/delay.h>
  30
  31 #include "hyperv.h"
  32 #include "hyperv_storage.h"
  33
  34
  35 static inline struct storvsc_device *alloc_stor_device(struct hv_device *device)
  36 {
  37         struct storvsc_device *stor_device;
  38
  39         stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
  40         if (!stor_device)
  41                 return NULL;
  42
  43         stor_device->destroy = false;
  44         init_waitqueue_head(&stor_device->waiting_to_drain);
  45         stor_device->device = device;
  46         device->ext = stor_device;
  47
  48         return stor_device;
  49 }
  50
  51
  52 static inline struct storvsc_device *get_in_stor_device(
  53                                         struct hv_device *device)
  54 {
  55         struct storvsc_device *stor_device;
  56         unsigned long flags;
  57
  58         spin_lock_irqsave(&device->channel->inbound_lock, flags);
  59         stor_device = (struct storvsc_device *)device->ext;
  60
  61         if (!stor_device)
  62                 goto get_in_err;
  63
  64         /*
  65          * If the device is being destroyed; allow incoming
  66          * traffic only to cleanup outstanding requests.
  67          */
  68
  69         if (stor_device->destroy  &&
  70                 (atomic_read(&stor_device->num_outstanding_req) == 0))
  71                 stor_device = NULL;
  72
  73 get_in_err:
  74         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
  75         return stor_device;
  76
  77 }
  78
  79 static int storvsc_channel_init(struct hv_device *device)
  80 {
  81         struct storvsc_device *stor_device;
  82         struct hv_storvsc_request *request;
  83         struct vstor_packet *vstor_packet;
  84         int ret, t;
  85
  86         stor_device = get_out_stor_device(device);
  87         if (!stor_device)
  88                 return -ENODEV;
  89
  90         request = &stor_device->init_request;
  91         vstor_packet = &request->vstor_packet;
  92
  93         /*
  94          * Now, initiate the vsc/vsp initialization protocol on the open
  95          * channel
  96          */
  97         memset(request, 0, sizeof(struct hv_storvsc_request));
  98         init_completion(&request->wait_event);
  99         vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
 100         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 101
 102         ret = vmbus_sendpacket(device->channel, vstor_packet,
 103                                sizeof(struct vstor_packet),
 104                                (unsigned long)request,
 105                                VM_PKT_DATA_INBAND,
 106                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 107         if (ret != 0)
 108                 goto cleanup;
 109
 110         t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
 111         if (t == 0) {
 112                 ret = -ETIMEDOUT;
 113                 goto cleanup;
 114         }
 115
 116         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 117             vstor_packet->status != 0)
 118                 goto cleanup;
 119
 120
 121         /* reuse the packet for version range supported */
 122         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 123         vstor_packet->operation = VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
 124         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 125
 126         vstor_packet->version.major_minor = VMSTOR_PROTOCOL_VERSION_CURRENT;
 127         FILL_VMSTOR_REVISION(vstor_packet->version.revision);
 128
 129         ret = vmbus_sendpacket(device->channel, vstor_packet,
 130                                sizeof(struct vstor_packet),
 131                                (unsigned long)request,
 132                                VM_PKT_DATA_INBAND,
 133                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 134         if (ret != 0)
 135                 goto cleanup;
 136
 137         t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
 138         if (t == 0) {
 139                 ret = -ETIMEDOUT;
 140                 goto cleanup;
 141         }
 142
 143         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 144             vstor_packet->status != 0)
 145                 goto cleanup;
 146
 147
 148         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 149         vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
 150         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 151         vstor_packet->storage_channel_properties.port_number =
 152                                         stor_device->port_number;
 153
 154         ret = vmbus_sendpacket(device->channel, vstor_packet,
 155                                sizeof(struct vstor_packet),
 156                                (unsigned long)request,
 157                                VM_PKT_DATA_INBAND,
 158                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 159
 160         if (ret != 0)
 161                 goto cleanup;
 162
 163         t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
 164         if (t == 0) {
 165                 ret = -ETIMEDOUT;
 166                 goto cleanup;
 167         }
 168
 169         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 170             vstor_packet->status != 0)
 171                 goto cleanup;
 172
 173         stor_device->path_id = vstor_packet->storage_channel_properties.path_id;
 174         stor_device->target_id
 175                 = vstor_packet->storage_channel_properties.target_id;
 176
 177         memset(vstor_packet, 0, sizeof(struct vstor_packet));
 178         vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
 179         vstor_packet->flags = REQUEST_COMPLETION_FLAG;
 180
 181         ret = vmbus_sendpacket(device->channel, vstor_packet,
 182                                sizeof(struct vstor_packet),
 183                                (unsigned long)request,
 184                                VM_PKT_DATA_INBAND,
 185                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 186
 187         if (ret != 0)
 188                 goto cleanup;
 189
 190         t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
 191         if (t == 0) {
 192                 ret = -ETIMEDOUT;
 193                 goto cleanup;
 194         }
 195
 196         if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
 197             vstor_packet->status != 0)
 198                 goto cleanup;
 199
 200
 201 cleanup:
 202         return ret;
 203 }
 204
 205 static void storvsc_on_io_completion(struct hv_device *device,
 206                                   struct vstor_packet *vstor_packet,
 207                                   struct hv_storvsc_request *request)
 208 {
 209         struct storvsc_device *stor_device;
 210         struct vstor_packet *stor_pkt;
 211
 212         stor_device = (struct storvsc_device *)device->ext;
 213
 214         stor_pkt = &request->vstor_packet;
 215
 216
 217         /* Copy over the status...etc */
 218         stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
 219         stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
 220         stor_pkt->vm_srb.sense_info_length =
 221         vstor_packet->vm_srb.sense_info_length;
 222
 223         if (vstor_packet->vm_srb.scsi_status != 0 ||
 224                 vstor_packet->vm_srb.srb_status != 1){
 225                 DPRINT_WARN(STORVSC,
 226                             "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
 227                             stor_pkt->vm_srb.cdb[0],
 228                             vstor_packet->vm_srb.scsi_status,
 229                             vstor_packet->vm_srb.srb_status);
 230         }
 231
 232         if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
 233                 /* CHECK_CONDITION */
 234                 if (vstor_packet->vm_srb.srb_status & 0x80) {
 235                         /* autosense data available */
 236                         DPRINT_WARN(STORVSC, "storvsc pkt %p autosense data "
 237                                     "valid - len %d\n", request,
 238                                     vstor_packet->vm_srb.sense_info_length);
 239
 240                         memcpy(request->sense_buffer,
 241                                vstor_packet->vm_srb.sense_data,
 242                                vstor_packet->vm_srb.sense_info_length);
 243
 244                 }
 245         }
 246
 247         stor_pkt->vm_srb.data_transfer_length =
 248         vstor_packet->vm_srb.data_transfer_length;
 249
 250         request->on_io_completion(request);
 251
 252         if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
 253                 stor_device->drain_notify)
 254                 wake_up(&stor_device->waiting_to_drain);
 255
 256
 257 }
 258
 259 static void storvsc_on_receive(struct hv_device *device,
 260                              struct vstor_packet *vstor_packet,
 261                              struct hv_storvsc_request *request)
 262 {
 263         switch (vstor_packet->operation) {
 264         case VSTOR_OPERATION_COMPLETE_IO:
 265                 storvsc_on_io_completion(device, vstor_packet, request);
 266                 break;
 267         case VSTOR_OPERATION_REMOVE_DEVICE:
 268
 269         default:
 270                 break;
 271         }
 272 }
 273
 274 static void storvsc_on_channel_callback(void *context)
 275 {
 276         struct hv_device *device = (struct hv_device *)context;
 277         struct storvsc_device *stor_device;
 278         u32 bytes_recvd;
 279         u64 request_id;
 280         unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
 281         struct hv_storvsc_request *request;
 282         int ret;
 283
 284
 285         stor_device = get_in_stor_device(device);
 286         if (!stor_device)
 287                 return;
 288
 289         do {
 290                 ret = vmbus_recvpacket(device->channel, packet,
 291                                        ALIGN(sizeof(struct vstor_packet), 8),
 292                                        &bytes_recvd, &request_id);
 293                 if (ret == 0 && bytes_recvd > 0) {
 294
 295                         request = (struct hv_storvsc_request *)
 296                                         (unsigned long)request_id;
 297
 298                         if ((request == &stor_device->init_request) ||
 299                             (request == &stor_device->reset_request)) {
 300
 301                                 memcpy(&request->vstor_packet, packet,
 302                                        sizeof(struct vstor_packet));
 303                                 complete(&request->wait_event);
 304                         } else {
 305                                 storvsc_on_receive(device,
 306                                                 (struct vstor_packet *)packet,
 307                                                 request);
 308                         }
 309                 } else {
 310                         break;
 311                 }
 312         } while (1);
 313
 314         return;
 315 }
 316
 317 static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size)
 318 {
 319         struct vmstorage_channel_properties props;
 320         int ret;
 321
 322         memset(&props, 0, sizeof(struct vmstorage_channel_properties));
 323
 324         /* Open the channel */
 325         ret = vmbus_open(device->channel,
 326                          ring_size,
 327                          ring_size,
 328                          (void *)&props,
 329                          sizeof(struct vmstorage_channel_properties),
 330                          storvsc_on_channel_callback, device);
 331
 332         if (ret != 0)
 333                 return ret;
 334
 335         ret = storvsc_channel_init(device);
 336
 337         return ret;
 338 }
 339
 340 int storvsc_dev_add(struct hv_device *device,
 341                                         void *additional_info)
 342 {
 343         struct storvsc_device *stor_device;
 344         struct storvsc_device_info *device_info;
 345         int ret = 0;
 346
 347         device_info = (struct storvsc_device_info *)additional_info;
 348         stor_device = alloc_stor_device(device);
 349         if (!stor_device)
 350                 return -ENOMEM;
 351
 352         /* Save the channel properties to our storvsc channel */
 353
 354         /*
 355          * If we support more than 1 scsi channel, we need to set the
 356          * port number here to the scsi channel but how do we get the
 357          * scsi channel prior to the bus scan.
 358          *
 359          * The host does not support this.
 360          */
 361
 362         stor_device->port_number = device_info->port_number;
 363         /* Send it back up */
 364         ret = storvsc_connect_to_vsp(device, device_info->ring_buffer_size);
 365         if (ret) {
 366                 kfree(stor_device);
 367                 return ret;
 368         }
 369         device_info->path_id = stor_device->path_id;
 370         device_info->target_id = stor_device->target_id;
 371
 372         return ret;
 373 }
 374
 375 int storvsc_dev_remove(struct hv_device *device)
 376 {
 377         struct storvsc_device *stor_device;
 378         unsigned long flags;
 379
 380         stor_device = (struct storvsc_device *)device->ext;
 381
 382         spin_lock_irqsave(&device->channel->inbound_lock, flags);
 383         stor_device->destroy = true;
 384         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
 385
 386         /*
 387          * At this point, all outbound traffic should be disable. We
 388          * only allow inbound traffic (responses) to proceed so that
 389          * outstanding requests can be completed.
 390          */
 391
 392         storvsc_wait_to_drain(stor_device);
 393
 394         /*
 395          * Since we have already drained, we don't need to busy wait
 396          * as was done in final_release_stor_device()
 397          * Note that we cannot set the ext pointer to NULL until
 398          * we have drained - to drain the outgoing packets, we need to
 399          * allow incoming packets.
 400          */
 401         spin_lock_irqsave(&device->channel->inbound_lock, flags);
 402         device->ext = NULL;
 403         spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
 404
 405         /* Close the channel */
 406         vmbus_close(device->channel);
 407
 408         kfree(stor_device);
 409         return 0;
 410 }
 411
 412 int storvsc_do_io(struct hv_device *device,
 413                               struct hv_storvsc_request *request)
 414 {
 415         struct storvsc_device *stor_device;
 416         struct vstor_packet *vstor_packet;
 417         int ret = 0;
 418
 419         vstor_packet = &request->vstor_packet;
 420         stor_device = get_out_stor_device(device);
 421
 422         if (!stor_device)
 423                 return -ENODEV;
 424
 425
 426         request->device  = device;
 427
 428
 429         vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
 430
 431         vstor_packet->vm_srb.length = sizeof(struct vmscsi_request);
 432
 433
 434         vstor_packet->vm_srb.sense_info_length = SENSE_BUFFER_SIZE;
 435
 436
 437         vstor_packet->vm_srb.data_transfer_length =
 438         request->data_buffer.len;
 439
 440         vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
 441
 442         if (request->data_buffer.len) {
 443                 ret = vmbus_sendpacket_multipagebuffer(device->channel,
 444                                 &request->data_buffer,
 445                                 vstor_packet,
 446                                 sizeof(struct vstor_packet),
 447                                 (unsigned long)request);
 448         } else {
 449                 ret = vmbus_sendpacket(device->channel, vstor_packet,
 450                                        sizeof(struct vstor_packet),
 451                                        (unsigned long)request,
 452                                        VM_PKT_DATA_INBAND,
 453                                        VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
 454         }
 455
 456         if (ret != 0)
 457                 return ret;
 458
 459         atomic_inc(&stor_device->num_outstanding_req);
 460
 461         return ret;
 462 }
 463
 464 /*
 465  * The channel properties uniquely specify how the device is to be
 466  * presented to the guest. Map this information for use by the block
 467  * driver. For Linux guests on Hyper-V, we emulate a scsi HBA in the guest
 468  * (storvsc_drv) and so scsi devices in the guest  are handled by
 469  * native upper level Linux drivers. Consequently, Hyper-V
 470  * block driver, while being a generic block driver, presently does not
 471  * deal with anything other than devices that would need to be presented
 472  * to the guest as an IDE disk.
 473  *
 474  * This function maps the channel properties as embedded in the input
 475  * parameter device_info onto information necessary to register the
 476  * corresponding block device.
 477  *
 478  * Currently, there is no way to stop the emulation of the block device
 479  * on the host side. And so, to prevent the native IDE drivers in Linux
 480  * from taking over these devices (to be managedby Hyper-V block
 481  * driver), we will take over if need be the major of the IDE controllers.
 482  *
 483  */
 484
 485 int storvsc_get_major_info(struct storvsc_device_info *device_info,
 486                             struct storvsc_major_info *major_info)
 487 {
 488         static bool ide0_registered;
 489         static bool ide1_registered;
 490
 491         /*
 492          * For now we only support IDE disks.
 493          */
 494         major_info->devname = "ide";
 495         major_info->diskname = "hd";
 496
 497         if (device_info->path_id) {
 498                 major_info->major = 22;
 499                 if (!ide1_registered) {
 500                         major_info->do_register = true;
 501                         ide1_registered = true;
 502                 } else
 503                         major_info->do_register = false;
 504
 505                 if (device_info->target_id)
 506                         major_info->index = 3;
 507                 else
 508                         major_info->index = 2;
 509
 510                 return 0;
 511         } else {
 512                 major_info->major = 3;
 513                 if (!ide0_registered) {
 514                         major_info->do_register = true;
 515                         ide0_registered = true;
 516                 } else
 517                         major_info->do_register = false;
 518
 519                 if (device_info->target_id)
 520                         major_info->index = 1;
 521                 else
 522                         major_info->index = 0;
 523
 524                 return 0;
 525         }
 526
 527         return -ENODEV;
 528 }