drivers/staging/hv/blkvsc_drv.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  */
  21 #include <linux/init.h>
  22 #include <linux/module.h>
  23 #include <linux/device.h>
  24 #include <linux/blkdev.h>
  25 #include <linux/major.h>
  26 #include <linux/delay.h>
  27 #include <linux/hdreg.h>
  28 #include <scsi/scsi.h>
  29 #include <scsi/scsi_cmnd.h>
  30 #include <scsi/scsi_eh.h>
  31 #include <scsi/scsi_dbg.h>
  32 #include "osd.h"
  33 #include "logging.h"
  34 #include "VersionInfo.h"
  35 #include "vmbus.h"
  36 #include "StorVscApi.h"
  37
  38
  39 #define BLKVSC_MINORS   64
  40
  41 enum blkvsc_device_type {
  42         UNKNOWN_DEV_TYPE,
  43         HARDDISK_TYPE,
  44         DVD_TYPE,
  45 };
  46
  47 /*
  48  * This request ties the struct request and struct
  49  * blkvsc_request/hv_storvsc_request together A struct request may be
  50  * represented by 1 or more struct blkvsc_request
  51  */
  52 struct blkvsc_request_group {
  53         int outstanding;
  54         int status;
  55         struct list_head blkvsc_req_list;       /* list of blkvsc_requests */
  56 };
  57
  58 struct blkvsc_request {
  59         /* blkvsc_request_group.blkvsc_req_list */
  60         struct list_head req_entry;
  61
  62         /* block_device_context.pending_list */
  63         struct list_head pend_entry;
  64
  65         /* This may be null if we generate a request internally */
  66         struct request *req;
  67
  68         struct block_device_context *dev;
  69
  70         /* The group this request is part of. Maybe null */
  71         struct blkvsc_request_group *group;
  72
  73         wait_queue_head_t wevent;
  74         int cond;
  75
  76         int write;
  77         sector_t sector_start;
  78         unsigned long sector_count;
  79
  80         unsigned char sense_buffer[SCSI_SENSE_BUFFERSIZE];
  81         unsigned char cmd_len;
  82         unsigned char cmnd[MAX_COMMAND_SIZE];
  83
  84         struct hv_storvsc_request request;
  85         /*
  86          * !!!DO NOT ADD ANYTHING BELOW HERE!!! Otherwise, memory can overlap,
  87          * because - The extension buffer falls right here and is pointed to by
  88          * request.Extension;
  89          * Which sounds like a horrible idea, who designed this?
  90          */
  91 };
  92
  93 /* Per device structure */
  94 struct block_device_context {
  95         /* point back to our device context */
  96         struct device_context *device_ctx;
  97         struct kmem_cache *request_pool;
  98         spinlock_t lock;
  99         struct gendisk *gd;
 100         enum blkvsc_device_type device_type;
 101         struct list_head pending_list;
 102
 103         unsigned char device_id[64];
 104         unsigned int device_id_len;
 105         int num_outstanding_reqs;
 106         int shutting_down;
 107         int media_not_present;
 108         unsigned int sector_size;
 109         sector_t capacity;
 110         unsigned int port;
 111         unsigned char path;
 112         unsigned char target;
 113         int users;
 114 };
 115
 116 /* Per driver */
 117 struct blkvsc_driver_context {
 118         /* !! These must be the first 2 fields !! */
 119         /* FIXME this is a bug! */
 120         struct driver_context drv_ctx;
 121         struct storvsc_driver_object drv_obj;
 122 };
 123
 124 /* Static decl */
 125 static int blkvsc_probe(struct device *dev);
 126 static int blkvsc_remove(struct device *device);
 127 static void blkvsc_shutdown(struct device *device);
 128
 129 static int blkvsc_open(struct block_device *bdev,  fmode_t mode);
 130 static int blkvsc_release(struct gendisk *disk, fmode_t mode);
 131 static int blkvsc_media_changed(struct gendisk *gd);
 132 static int blkvsc_revalidate_disk(struct gendisk *gd);
 133 static int blkvsc_getgeo(struct block_device *bd, struct hd_geometry *hg);
 134 static int blkvsc_ioctl(struct block_device *bd, fmode_t mode,
 135                         unsigned cmd, unsigned long argument);
 136 static void blkvsc_request(struct request_queue *queue);
 137 static void blkvsc_request_completion(struct hv_storvsc_request *request);
 138 static int blkvsc_do_request(struct block_device_context *blkdev,
 139                              struct request *req);
 140 static int blkvsc_submit_request(struct blkvsc_request *blkvsc_req,
 141                 void (*request_completion)(struct hv_storvsc_request *));
 142 static void blkvsc_init_rw(struct blkvsc_request *blkvsc_req);
 143 static void blkvsc_cmd_completion(struct hv_storvsc_request *request);
 144 static int blkvsc_do_inquiry(struct block_device_context *blkdev);
 145 static int blkvsc_do_read_capacity(struct block_device_context *blkdev);
 146 static int blkvsc_do_read_capacity16(struct block_device_context *blkdev);
 147 static int blkvsc_do_flush(struct block_device_context *blkdev);
 148 static int blkvsc_cancel_pending_reqs(struct block_device_context *blkdev);
 149 static int blkvsc_do_pending_reqs(struct block_device_context *blkdev);
 150
 151
 152 static int blkvsc_ringbuffer_size = BLKVSC_RING_BUFFER_SIZE;
 153
 154 /* The one and only one */
 155 static struct blkvsc_driver_context g_blkvsc_drv;
 156
 157 static struct block_device_operations block_ops = {
 158         .owner = THIS_MODULE,
 159         .open = blkvsc_open,
 160         .release = blkvsc_release,
 161         .media_changed = blkvsc_media_changed,
 162         .revalidate_disk = blkvsc_revalidate_disk,
 163         .getgeo = blkvsc_getgeo,
 164         .ioctl  = blkvsc_ioctl,
 165 };
 166
 167 /**
 168  * blkvsc_drv_init -  BlkVsc driver initialization.
 169  */
 170 static int blkvsc_drv_init(int (*drv_init)(struct hv_driver *drv))
 171 {
 172         struct storvsc_driver_object *storvsc_drv_obj = &g_blkvsc_drv.drv_obj;
 173         struct driver_context *drv_ctx = &g_blkvsc_drv.drv_ctx;
 174         int ret;
 175
 176         DPRINT_ENTER(BLKVSC_DRV);
 177
 178         vmbus_get_interface(&storvsc_drv_obj->Base.VmbusChannelInterface);
 179
 180         storvsc_drv_obj->RingBufferSize = blkvsc_ringbuffer_size;
 181
 182         /* Callback to client driver to complete the initialization */
 183         drv_init(&storvsc_drv_obj->Base);
 184
 185         drv_ctx->driver.name = storvsc_drv_obj->Base.name;
 186         memcpy(&drv_ctx->class_id, &storvsc_drv_obj->Base.deviceType,
 187                sizeof(struct hv_guid));
 188
 189         drv_ctx->probe = blkvsc_probe;
 190         drv_ctx->remove = blkvsc_remove;
 191         drv_ctx->shutdown = blkvsc_shutdown;
 192
 193         /* The driver belongs to vmbus */
 194         ret = vmbus_child_driver_register(drv_ctx);
 195
 196         DPRINT_EXIT(BLKVSC_DRV);
 197
 198         return ret;
 199 }
 200
 201 static int blkvsc_drv_exit_cb(struct device *dev, void *data)
 202 {
 203         struct device **curr = (struct device **)data;
 204         *curr = dev;
 205         return 1; /* stop iterating */
 206 }
 207
 208 static void blkvsc_drv_exit(void)
 209 {
 210         struct storvsc_driver_object *storvsc_drv_obj = &g_blkvsc_drv.drv_obj;
 211         struct driver_context *drv_ctx = &g_blkvsc_drv.drv_ctx;
 212         struct device *current_dev;
 213         int ret;
 214
 215         DPRINT_ENTER(BLKVSC_DRV);
 216
 217         while (1) {
 218                 current_dev = NULL;
 219
 220                 /* Get the device */
 221                 ret = driver_for_each_device(&drv_ctx->driver, NULL,
 222                                              (void *) &current_dev,
 223                                              blkvsc_drv_exit_cb);
 224
 225                 if (ret)
 226                         DPRINT_WARN(BLKVSC_DRV,
 227                                     "driver_for_each_device returned %d", ret);
 228
 229
 230                 if (current_dev == NULL)
 231                         break;
 232
 233                 /* Initiate removal from the top-down */
 234                 device_unregister(current_dev);
 235         }
 236
 237         if (storvsc_drv_obj->Base.OnCleanup)
 238                 storvsc_drv_obj->Base.OnCleanup(&storvsc_drv_obj->Base);
 239
 240         vmbus_child_driver_unregister(drv_ctx);
 241
 242         DPRINT_EXIT(BLKVSC_DRV);
 243
 244         return;
 245 }
 246
 247 /**
 248  * blkvsc_probe - Add a new device for this driver
 249  */
 250 static int blkvsc_probe(struct device *device)
 251 {
 252         struct driver_context *driver_ctx =
 253                                 driver_to_driver_context(device->driver);
 254         struct blkvsc_driver_context *blkvsc_drv_ctx =
 255                                 (struct blkvsc_driver_context *)driver_ctx;
 256         struct storvsc_driver_object *storvsc_drv_obj =
 257                                 &blkvsc_drv_ctx->drv_obj;
 258         struct device_context *device_ctx = device_to_device_context(device);
 259         struct hv_device *device_obj = &device_ctx->device_obj;
 260
 261         struct block_device_context *blkdev = NULL;
 262         struct storvsc_device_info device_info;
 263         int major = 0;
 264         int devnum = 0;
 265         int ret = 0;
 266         static int ide0_registered;
 267         static int ide1_registered;
 268
 269         DPRINT_ENTER(BLKVSC_DRV);
 270
 271         DPRINT_DBG(BLKVSC_DRV, "blkvsc_probe - enter");
 272
 273         if (!storvsc_drv_obj->Base.OnDeviceAdd) {
 274                 DPRINT_ERR(BLKVSC_DRV, "OnDeviceAdd() not set");
 275                 ret = -1;
 276                 goto Cleanup;
 277         }
 278
 279         blkdev = kzalloc(sizeof(struct block_device_context), GFP_KERNEL);
 280         if (!blkdev) {
 281                 ret = -ENOMEM;
 282                 goto Cleanup;
 283         }
 284
 285         INIT_LIST_HEAD(&blkdev->pending_list);
 286
 287         /* Initialize what we can here */
 288         spin_lock_init(&blkdev->lock);
 289
 290         ASSERT(sizeof(struct blkvsc_request_group) <=
 291                 sizeof(struct blkvsc_request));
 292
 293         blkdev->request_pool = kmem_cache_create(dev_name(&device_ctx->device),
 294                                         sizeof(struct blkvsc_request) +
 295                                         storvsc_drv_obj->RequestExtSize, 0,
 296                                         SLAB_HWCACHE_ALIGN, NULL);
 297         if (!blkdev->request_pool) {
 298                 ret = -ENOMEM;
 299                 goto Cleanup;
 300         }
 301
 302
 303         /* Call to the vsc driver to add the device */
 304         ret = storvsc_drv_obj->Base.OnDeviceAdd(device_obj, &device_info);
 305         if (ret != 0) {
 306                 DPRINT_ERR(BLKVSC_DRV, "unable to add blkvsc device");
 307                 goto Cleanup;
 308         }
 309
 310         blkdev->device_ctx = device_ctx;
 311         /* this identified the device 0 or 1 */
 312         blkdev->target = device_info.TargetId;
 313         /* this identified the ide ctrl 0 or 1 */
 314         blkdev->path = device_info.PathId;
 315
 316         dev_set_drvdata(device, blkdev);
 317
 318         /* Calculate the major and device num */
 319         if (blkdev->path == 0) {
 320                 major = IDE0_MAJOR;
 321                 devnum = blkdev->path + blkdev->target;         /* 0 or 1 */
 322
 323                 if (!ide0_registered) {
 324                         ret = register_blkdev(major, "ide");
 325                         if (ret != 0) {
 326                                 DPRINT_ERR(BLKVSC_DRV,
 327                                            "register_blkdev() failed! ret %d",
 328                                            ret);
 329                                 goto Remove;
 330                         }
 331
 332                         ide0_registered = 1;
 333                 }
 334         } else if (blkdev->path == 1) {
 335                 major = IDE1_MAJOR;
 336                 devnum = blkdev->path + blkdev->target + 1; /* 2 or 3 */
 337
 338                 if (!ide1_registered) {
 339                         ret = register_blkdev(major, "ide");
 340                         if (ret != 0) {
 341                                 DPRINT_ERR(BLKVSC_DRV,
 342                                            "register_blkdev() failed! ret %d",
 343                                            ret);
 344                                 goto Remove;
 345                         }
 346
 347                         ide1_registered = 1;
 348                 }
 349         } else {
 350                 DPRINT_ERR(BLKVSC_DRV, "invalid pathid");
 351                 ret = -1;
 352                 goto Cleanup;
 353         }
 354
 355         DPRINT_INFO(BLKVSC_DRV, "blkvsc registered for major %d!!", major);
 356
 357         blkdev->gd = alloc_disk(BLKVSC_MINORS);
 358         if (!blkdev->gd) {
 359                 DPRINT_ERR(BLKVSC_DRV, "register_blkdev() failed! ret %d", ret);
 360                 ret = -1;
 361                 goto Cleanup;
 362         }
 363
 364         blkdev->gd->queue = blk_init_queue(blkvsc_request, &blkdev->lock);
 365
 366         blk_queue_max_segment_size(blkdev->gd->queue, PAGE_SIZE);
 367         blk_queue_max_phys_segments(blkdev->gd->queue,
 368                                     MAX_MULTIPAGE_BUFFER_COUNT);
 369         blk_queue_max_hw_segments(blkdev->gd->queue,
 370                                   MAX_MULTIPAGE_BUFFER_COUNT);
 371         blk_queue_segment_boundary(blkdev->gd->queue, PAGE_SIZE-1);
 372         blk_queue_bounce_limit(blkdev->gd->queue, BLK_BOUNCE_ANY);
 373         blk_queue_dma_alignment(blkdev->gd->queue, 511);
 374
 375         blkdev->gd->major = major;
 376         if (devnum == 1 || devnum == 3)
 377                 blkdev->gd->first_minor = BLKVSC_MINORS;
 378         else
 379                 blkdev->gd->first_minor = 0;
 380         blkdev->gd->fops = &block_ops;
 381         blkdev->gd->private_data = blkdev;
 382         sprintf(blkdev->gd->disk_name, "hd%c", 'a' + devnum);
 383
 384         blkvsc_do_inquiry(blkdev);
 385         if (blkdev->device_type == DVD_TYPE) {
 386                 set_disk_ro(blkdev->gd, 1);
 387                 blkdev->gd->flags |= GENHD_FL_REMOVABLE;
 388                 blkvsc_do_read_capacity(blkdev);
 389         } else {
 390                 blkvsc_do_read_capacity16(blkdev);
 391         }
 392
 393         set_capacity(blkdev->gd, blkdev->capacity * (blkdev->sector_size/512));
 394         blk_queue_logical_block_size(blkdev->gd->queue, blkdev->sector_size);
 395         /* go! */
 396         add_disk(blkdev->gd);
 397
 398         DPRINT_INFO(BLKVSC_DRV, "%s added!! capacity %lu sector_size %d",
 399                     blkdev->gd->disk_name, (unsigned long)blkdev->capacity,
 400                     blkdev->sector_size);
 401
 402         return ret;
 403
 404 Remove:
 405         storvsc_drv_obj->Base.OnDeviceRemove(device_obj);
 406
 407 Cleanup:
 408         if (blkdev) {
 409                 if (blkdev->request_pool) {
 410                         kmem_cache_destroy(blkdev->request_pool);
 411                         blkdev->request_pool = NULL;
 412                 }
 413                 kfree(blkdev);
 414                 blkdev = NULL;
 415         }
 416
 417         DPRINT_EXIT(BLKVSC_DRV);
 418
 419         return ret;
 420 }
 421
 422 static void blkvsc_shutdown(struct device *device)
 423 {
 424         struct block_device_context *blkdev = dev_get_drvdata(device);
 425         unsigned long flags;
 426
 427         if (!blkdev)
 428                 return;
 429
 430         DPRINT_DBG(BLKVSC_DRV, "blkvsc_shutdown - users %d disk %s\n",
 431                    blkdev->users, blkdev->gd->disk_name);
 432
 433         spin_lock_irqsave(&blkdev->lock, flags);
 434
 435         blkdev->shutting_down = 1;
 436
 437         blk_stop_queue(blkdev->gd->queue);
 438
 439         spin_unlock_irqrestore(&blkdev->lock, flags);
 440
 441         while (blkdev->num_outstanding_reqs) {
 442                 DPRINT_INFO(STORVSC, "waiting for %d requests to complete...",
 443                             blkdev->num_outstanding_reqs);
 444                 udelay(100);
 445         }
 446
 447         blkvsc_do_flush(blkdev);
 448
 449         spin_lock_irqsave(&blkdev->lock, flags);
 450
 451         blkvsc_cancel_pending_reqs(blkdev);
 452
 453         spin_unlock_irqrestore(&blkdev->lock, flags);
 454 }
 455
 456 static int blkvsc_do_flush(struct block_device_context *blkdev)
 457 {
 458         struct blkvsc_request *blkvsc_req;
 459
 460         DPRINT_DBG(BLKVSC_DRV, "blkvsc_do_flush()\n");
 461
 462         if (blkdev->device_type != HARDDISK_TYPE)
 463                 return 0;
 464
 465         blkvsc_req = kmem_cache_alloc(blkdev->request_pool, GFP_KERNEL);
 466         if (!blkvsc_req)
 467                 return -ENOMEM;
 468
 469         memset(blkvsc_req, 0, sizeof(struct blkvsc_request));
 470         init_waitqueue_head(&blkvsc_req->wevent);
 471         blkvsc_req->dev = blkdev;
 472         blkvsc_req->req = NULL;
 473         blkvsc_req->write = 0;
 474
 475         blkvsc_req->request.DataBuffer.PfnArray[0] = 0;
 476         blkvsc_req->request.DataBuffer.Offset = 0;
 477         blkvsc_req->request.DataBuffer.Length = 0;
 478
 479         blkvsc_req->cmnd[0] = SYNCHRONIZE_CACHE;
 480         blkvsc_req->cmd_len = 10;
 481
 482         /*
 483          * Set this here since the completion routine may be invoked and
 484          * completed before we return
 485          */
 486         blkvsc_req->cond = 0;
 487         blkvsc_submit_request(blkvsc_req, blkvsc_cmd_completion);
 488
 489         wait_event_interruptible(blkvsc_req->wevent, blkvsc_req->cond);
 490
 491         kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
 492
 493         return 0;
 494 }
 495
 496 /* Do a scsi INQUIRY cmd here to get the device type (ie disk or dvd) */
 497 static int blkvsc_do_inquiry(struct block_device_context *blkdev)
 498 {
 499         struct blkvsc_request *blkvsc_req;
 500         struct page *page_buf;
 501         unsigned char *buf;
 502         unsigned char device_type;
 503
 504         DPRINT_DBG(BLKVSC_DRV, "blkvsc_do_inquiry()\n");
 505
 506         blkvsc_req = kmem_cache_alloc(blkdev->request_pool, GFP_KERNEL);
 507         if (!blkvsc_req)
 508                 return -ENOMEM;
 509
 510         memset(blkvsc_req, 0, sizeof(struct blkvsc_request));
 511         page_buf = alloc_page(GFP_KERNEL);
 512         if (!page_buf) {
 513                 kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
 514                 return -ENOMEM;
 515         }
 516
 517         init_waitqueue_head(&blkvsc_req->wevent);
 518         blkvsc_req->dev = blkdev;
 519         blkvsc_req->req = NULL;
 520         blkvsc_req->write = 0;
 521
 522         blkvsc_req->request.DataBuffer.PfnArray[0] = page_to_pfn(page_buf);
 523         blkvsc_req->request.DataBuffer.Offset = 0;
 524         blkvsc_req->request.DataBuffer.Length = 64;
 525
 526         blkvsc_req->cmnd[0] = INQUIRY;
 527         blkvsc_req->cmnd[1] = 0x1;              /* Get product data */
 528         blkvsc_req->cmnd[2] = 0x83;             /* mode page 83 */
 529         blkvsc_req->cmnd[4] = 64;
 530         blkvsc_req->cmd_len = 6;
 531
 532         /*
 533          * Set this here since the completion routine may be invoked and
 534          * completed before we return
 535          */
 536         blkvsc_req->cond = 0;
 537
 538         blkvsc_submit_request(blkvsc_req, blkvsc_cmd_completion);
 539
 540         DPRINT_DBG(BLKVSC_DRV, "waiting %p to complete - cond %d\n",
 541                    blkvsc_req, blkvsc_req->cond);
 542
 543         wait_event_interruptible(blkvsc_req->wevent, blkvsc_req->cond);
 544
 545         buf = kmap(page_buf);
 546
 547         /* print_hex_dump_bytes("", DUMP_PREFIX_NONE, buf, 64); */
 548         /* be to le */
 549         device_type = buf[0] & 0x1F;
 550
 551         if (device_type == 0x0) {
 552                 blkdev->device_type = HARDDISK_TYPE;
 553         } else if (device_type == 0x5) {
 554                 blkdev->device_type = DVD_TYPE;
 555         } else {
 556                 /* TODO: this is currently unsupported device type */
 557                 blkdev->device_type = UNKNOWN_DEV_TYPE;
 558         }
 559
 560         DPRINT_DBG(BLKVSC_DRV, "device type %d \n", device_type);
 561
 562         blkdev->device_id_len = buf[7];
 563         if (blkdev->device_id_len > 64)
 564                 blkdev->device_id_len = 64;
 565
 566         memcpy(blkdev->device_id, &buf[8], blkdev->device_id_len);
 567         /* printk_hex_dump_bytes("", DUMP_PREFIX_NONE, blkdev->device_id,
 568          * blkdev->device_id_len); */
 569
 570         kunmap(page_buf);
 571
 572         __free_page(page_buf);
 573
 574         kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
 575
 576         return 0;
 577 }
 578
 579 /* Do a scsi READ_CAPACITY cmd here to get the size of the disk */
 580 static int blkvsc_do_read_capacity(struct block_device_context *blkdev)
 581 {
 582         struct blkvsc_request *blkvsc_req;
 583         struct page *page_buf;
 584         unsigned char *buf;
 585         struct scsi_sense_hdr sense_hdr;
 586
 587         DPRINT_DBG(BLKVSC_DRV, "blkvsc_do_read_capacity()\n");
 588
 589         blkdev->sector_size = 0;
 590         blkdev->capacity = 0;
 591         blkdev->media_not_present = 0; /* assume a disk is present */
 592
 593         blkvsc_req = kmem_cache_alloc(blkdev->request_pool, GFP_KERNEL);
 594         if (!blkvsc_req)
 595                 return -ENOMEM;
 596
 597         memset(blkvsc_req, 0, sizeof(struct blkvsc_request));
 598         page_buf = alloc_page(GFP_KERNEL);
 599         if (!page_buf) {
 600                 kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
 601                 return -ENOMEM;
 602         }
 603
 604         init_waitqueue_head(&blkvsc_req->wevent);
 605         blkvsc_req->dev = blkdev;
 606         blkvsc_req->req = NULL;
 607         blkvsc_req->write = 0;
 608
 609         blkvsc_req->request.DataBuffer.PfnArray[0] = page_to_pfn(page_buf);
 610         blkvsc_req->request.DataBuffer.Offset = 0;
 611         blkvsc_req->request.DataBuffer.Length = 8;
 612
 613         blkvsc_req->cmnd[0] = READ_CAPACITY;
 614         blkvsc_req->cmd_len = 16;
 615
 616         /*
 617          * Set this here since the completion routine may be invoked
 618          * and completed before we return
 619          */
 620         blkvsc_req->cond = 0;
 621
 622         blkvsc_submit_request(blkvsc_req, blkvsc_cmd_completion);
 623
 624         DPRINT_DBG(BLKVSC_DRV, "waiting %p to complete - cond %d\n",
 625                    blkvsc_req, blkvsc_req->cond);
 626
 627         wait_event_interruptible(blkvsc_req->wevent, blkvsc_req->cond);
 628
 629         /* check error */
 630         if (blkvsc_req->request.Status) {
 631                 scsi_normalize_sense(blkvsc_req->sense_buffer,
 632                                      SCSI_SENSE_BUFFERSIZE, &sense_hdr);
 633
 634                 if (sense_hdr.asc == 0x3A) {
 635                         /* Medium not present */
 636                         blkdev->media_not_present = 1;
 637                 }
 638                 return 0;
 639         }
 640         buf = kmap(page_buf);
 641
 642         /* be to le */
 643         blkdev->capacity = ((buf[0] << 24) | (buf[1] << 16) |
 644                             (buf[2] << 8) | buf[3]) + 1;
 645         blkdev->sector_size = (buf[4] << 24) | (buf[5] << 16) |
 646                               (buf[6] << 8) | buf[7];
 647
 648         kunmap(page_buf);
 649
 650         __free_page(page_buf);
 651
 652         kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
 653
 654         return 0;
 655 }
 656
 657 static int blkvsc_do_read_capacity16(struct block_device_context *blkdev)
 658 {
 659         struct blkvsc_request *blkvsc_req;
 660         struct page *page_buf;
 661         unsigned char *buf;
 662         struct scsi_sense_hdr sense_hdr;
 663
 664         DPRINT_DBG(BLKVSC_DRV, "blkvsc_do_read_capacity16()\n");
 665
 666         blkdev->sector_size = 0;
 667         blkdev->capacity = 0;
 668         blkdev->media_not_present = 0; /* assume a disk is present */
 669
 670         blkvsc_req = kmem_cache_alloc(blkdev->request_pool, GFP_KERNEL);
 671         if (!blkvsc_req)
 672                 return -ENOMEM;
 673
 674         memset(blkvsc_req, 0, sizeof(struct blkvsc_request));
 675         page_buf = alloc_page(GFP_KERNEL);
 676         if (!page_buf) {
 677                 kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
 678                 return -ENOMEM;
 679         }
 680
 681         init_waitqueue_head(&blkvsc_req->wevent);
 682         blkvsc_req->dev = blkdev;
 683         blkvsc_req->req = NULL;
 684         blkvsc_req->write = 0;
 685
 686         blkvsc_req->request.DataBuffer.PfnArray[0] = page_to_pfn(page_buf);
 687         blkvsc_req->request.DataBuffer.Offset = 0;
 688         blkvsc_req->request.DataBuffer.Length = 12;
 689
 690         blkvsc_req->cmnd[0] = 0x9E; /* READ_CAPACITY16; */
 691         blkvsc_req->cmd_len = 16;
 692
 693         /*
 694          * Set this here since the completion routine may be invoked
 695          * and completed before we return
 696          */
 697         blkvsc_req->cond = 0;
 698
 699         blkvsc_submit_request(blkvsc_req, blkvsc_cmd_completion);
 700
 701         DPRINT_DBG(BLKVSC_DRV, "waiting %p to complete - cond %d\n",
 702                    blkvsc_req, blkvsc_req->cond);
 703
 704         wait_event_interruptible(blkvsc_req->wevent, blkvsc_req->cond);
 705
 706         /* check error */
 707         if (blkvsc_req->request.Status) {
 708                 scsi_normalize_sense(blkvsc_req->sense_buffer,
 709                                      SCSI_SENSE_BUFFERSIZE, &sense_hdr);
 710                 if (sense_hdr.asc == 0x3A) {
 711                         /* Medium not present */
 712                         blkdev->media_not_present = 1;
 713                 }
 714                 return 0;
 715         }
 716         buf = kmap(page_buf);
 717
 718         /* be to le */
 719         blkdev->capacity = be64_to_cpu(*(unsigned long long *) &buf[0]) + 1;
 720         blkdev->sector_size = be32_to_cpu(*(unsigned int *)&buf[8]);
 721
 722 #if 0
 723         blkdev->capacity = ((buf[0] << 24) | (buf[1] << 16) |
 724                             (buf[2] << 8) | buf[3]) + 1;
 725         blkdev->sector_size = (buf[4] << 24) | (buf[5] << 16) |
 726                               (buf[6] << 8) | buf[7];
 727 #endif
 728
 729         kunmap(page_buf);
 730
 731         __free_page(page_buf);
 732
 733         kmem_cache_free(blkvsc_req->dev->request_pool, blkvsc_req);
 734
 735         return 0;
 736 }
 737
 738 /**
 739  * blkvsc_remove() - Callback when our device is removed
 740  */
 741 static int blkvsc_remove(struct device *device)
 742 {
 743         struct driver_context *driver_ctx =
 744                                 driver_to_driver_context(device->driver);
 745         struct blkvsc_driver_context *blkvsc_drv_ctx =
 746                                 (struct blkvsc_driver_context *)driver_ctx;
 747         struct storvsc_driver_object *storvsc_drv_obj =
 748                                 &blkvsc_drv_ctx->drv_obj;
 749         struct device_context *device_ctx = device_to_device_context(device);
 750         struct hv_device *device_obj = &device_ctx->device_obj;
 751         struct block_device_context *blkdev = dev_get_drvdata(device);
 752         unsigned long flags;
 753         int ret;
 754
 755         DPRINT_ENTER(BLKVSC_DRV);
 756
 757         DPRINT_DBG(BLKVSC_DRV, "blkvsc_remove()\n");
 758
 759         if (!storvsc_drv_obj->Base.OnDeviceRemove) {
 760                 DPRINT_EXIT(BLKVSC_DRV);
 761                 return -1;
 762         }
 763
 764         /*
 765          * Call to the vsc driver to let it know that the device is being
 766          * removed
 767          */
 768         ret = storvsc_drv_obj->Base.OnDeviceRemove(device_obj);
 769         if (ret != 0) {
 770                 /* TODO: */
 771                 DPRINT_ERR(BLKVSC_DRV,
 772                            "unable to remove blkvsc device (ret %d)", ret);
 773         }
 774
 775         /* Get to a known state */
 776         spin_lock_irqsave(&blkdev->lock, flags);
 777
 778         blkdev->shutting_down = 1;
 779
 780         blk_stop_queue(blkdev->gd->queue);
 781
 782         spin_unlock_irqrestore(&blkdev->lock, flags);
 783
 784         while (blkdev->num_outstanding_reqs) {
 785                 DPRINT_INFO(STORVSC, "waiting for %d requests to complete...",
 786                             blkdev->num_outstanding_reqs);
 787                 udelay(100);
 788         }
 789
 790         blkvsc_do_flush(blkdev);
 791
 792         spin_lock_irqsave(&blkdev->lock, flags);
 793
 794         blkvsc_cancel_pending_reqs(blkdev);
 795
 796         spin_unlock_irqrestore(&blkdev->lock, flags);
 797
 798         blk_cleanup_queue(blkdev->gd->queue);
 799
 800         del_gendisk(blkdev->gd);
 801
 802         kmem_cache_destroy(blkdev->request_pool);
 803
 804         kfree(blkdev);
 805
 806         DPRINT_EXIT(BLKVSC_DRV);
 807
 808         return ret;
 809 }
 810
 811 static void blkvsc_init_rw(struct blkvsc_request *blkvsc_req)
 812 {
 813         ASSERT(blkvsc_req->req);
 814         ASSERT(blkvsc_req->sector_count <= (MAX_MULTIPAGE_BUFFER_COUNT*8));
 815
 816         blkvsc_req->cmd_len = 16;
 817
 818         if (blkvsc_req->sector_start > 0xffffffff) {
 819                 if (rq_data_dir(blkvsc_req->req)) {
 820                         blkvsc_req->write = 1;
 821                         blkvsc_req->cmnd[0] = WRITE_16;
 822                 } else {
 823                         blkvsc_req->write = 0;
 824                         blkvsc_req->cmnd[0] = READ_16;
 825                 }
 826
 827                 blkvsc_req->cmnd[1] |= blk_fua_rq(blkvsc_req->req) ? 0x8 : 0;
 828
 829                 *(unsigned long long *)&blkvsc_req->cmnd[2] =
 830                                 cpu_to_be64(blkvsc_req->sector_start);
 831                 *(unsigned int *)&blkvsc_req->cmnd[10] =
 832                                 cpu_to_be32(blkvsc_req->sector_count);
 833         } else if ((blkvsc_req->sector_count > 0xff) ||
 834                    (blkvsc_req->sector_start > 0x1fffff)) {
 835                 if (rq_data_dir(blkvsc_req->req)) {
 836                         blkvsc_req->write = 1;
 837                         blkvsc_req->cmnd[0] = WRITE_10;
 838                 } else {
 839                         blkvsc_req->write = 0;
 840                         blkvsc_req->cmnd[0] = READ_10;
 841                 }
 842
 843                 blkvsc_req->cmnd[1] |= blk_fua_rq(blkvsc_req->req) ? 0x8 : 0;
 844
 845                 *(unsigned int *)&blkvsc_req->cmnd[2] =
 846                                 cpu_to_be32(blkvsc_req->sector_start);
 847                 *(unsigned short *)&blkvsc_req->cmnd[7] =
 848                                 cpu_to_be16(blkvsc_req->sector_count);
 849         } else {
 850                 if (rq_data_dir(blkvsc_req->req)) {
 851                         blkvsc_req->write = 1;
 852                         blkvsc_req->cmnd[0] = WRITE_6;
 853                 } else {
 854                         blkvsc_req->write = 0;
 855                         blkvsc_req->cmnd[0] = READ_6;
 856                 }
 857
 858                 *(unsigned int *)&blkvsc_req->cmnd[1] =
 859                                 cpu_to_be32(blkvsc_req->sector_start) >> 8;
 860                 blkvsc_req->cmnd[1] &= 0x1f;
 861                 blkvsc_req->cmnd[4] = (unsigned char)blkvsc_req->sector_count;
 862         }
 863 }
 864
 865 static int blkvsc_submit_request(struct blkvsc_request *blkvsc_req,
 866                         void (*request_completion)(struct hv_storvsc_request *))
 867 {
 868         struct block_device_context *blkdev = blkvsc_req->dev;
 869         struct device_context *device_ctx = blkdev->device_ctx;
 870         struct driver_context *driver_ctx =
 871                         driver_to_driver_context(device_ctx->device.driver);
 872         struct blkvsc_driver_context *blkvsc_drv_ctx =
 873                         (struct blkvsc_driver_context *)driver_ctx;
 874         struct storvsc_driver_object *storvsc_drv_obj =
 875                         &blkvsc_drv_ctx->drv_obj;
 876         struct hv_storvsc_request *storvsc_req;
 877         int ret;
 878
 879         DPRINT_DBG(BLKVSC_DRV, "blkvsc_submit_request() - "
 880                    "req %p type %s start_sector %lu count %ld offset %d "
 881                    "len %d\n", blkvsc_req,
 882                    (blkvsc_req->write) ? "WRITE" : "READ",
 883                    (unsigned long) blkvsc_req->sector_start,
 884                    blkvsc_req->sector_count,
 885                    blkvsc_req->request.DataBuffer.Offset,
 886                    blkvsc_req->request.DataBuffer.Length);
 887 #if 0
 888         for (i = 0; i < (blkvsc_req->request.DataBuffer.Length >> 12); i++) {
 889                 DPRINT_DBG(BLKVSC_DRV, "blkvsc_submit_request() - "
 890                            "req %p pfn[%d] %llx\n",
 891                            blkvsc_req, i,
 892                            blkvsc_req->request.DataBuffer.PfnArray[i]);
 893         }
 894 #endif
 895
 896         storvsc_req = &blkvsc_req->request;
 897         storvsc_req->Extension = (void *)((unsigned long)blkvsc_req +
 898                                           sizeof(struct blkvsc_request));
 899
 900         storvsc_req->Type = blkvsc_req->write ? WRITE_TYPE : READ_TYPE;
 901
 902         storvsc_req->OnIOCompletion = request_completion;
 903         storvsc_req->Context = blkvsc_req;
 904
 905         storvsc_req->Host = blkdev->port;
 906         storvsc_req->Bus = blkdev->path;
 907         storvsc_req->TargetId = blkdev->target;
 908         storvsc_req->LunId = 0;  /* this is not really used at all */
 909
 910         storvsc_req->CdbLen = blkvsc_req->cmd_len;
 911         storvsc_req->Cdb = blkvsc_req->cmnd;
 912
 913         storvsc_req->SenseBuffer = blkvsc_req->sense_buffer;
 914         storvsc_req->SenseBufferSize = SCSI_SENSE_BUFFERSIZE;
 915
 916         ret = storvsc_drv_obj->OnIORequest(&blkdev->device_ctx->device_obj,
 917                                            &blkvsc_req->request);
 918         if (ret == 0)
 919                 blkdev->num_outstanding_reqs++;
 920
 921         return ret;
 922 }
 923
 924 /*
 925  * We break the request into 1 or more blkvsc_requests and submit
 926  * them.  If we cant submit them all, we put them on the
 927  * pending_list. The blkvsc_request() will work on the pending_list.
 928  */
 929 static int blkvsc_do_request(struct block_device_context *blkdev,
 930                              struct request *req)
 931 {
 932         struct bio *bio = NULL;
 933         struct bio_vec *bvec = NULL;
 934         struct bio_vec *prev_bvec = NULL;
 935         struct blkvsc_request *blkvsc_req = NULL;
 936         struct blkvsc_request *tmp;
 937         int databuf_idx = 0;
 938         int seg_idx = 0;
 939         sector_t start_sector;
 940         unsigned long num_sectors = 0;
 941         int ret = 0;
 942         int pending = 0;
 943         struct blkvsc_request_group *group = NULL;
 944
 945         DPRINT_DBG(BLKVSC_DRV, "blkdev %p req %p sect %lu \n", blkdev, req,
 946                   (unsigned long)blk_rq_pos(req));
 947
 948         /* Create a group to tie req to list of blkvsc_reqs */
 949         group = kmem_cache_alloc(blkdev->request_pool, GFP_ATOMIC);
 950         if (!group)
 951                 return -ENOMEM;
 952
 953         INIT_LIST_HEAD(&group->blkvsc_req_list);
 954         group->outstanding = group->status = 0;
 955
 956         start_sector = blk_rq_pos(req);
 957
 958         /* foreach bio in the request */
 959         if (req->bio) {
 960                 for (bio = req->bio; bio; bio = bio->bi_next) {
 961                         /*
 962                          * Map this bio into an existing or new storvsc request
 963                          */
 964                         bio_for_each_segment(bvec, bio, seg_idx) {
 965                                 DPRINT_DBG(BLKVSC_DRV, "bio_for_each_segment() "
 966                                            "- req %p bio %p bvec %p seg_idx %d "
 967                                            "databuf_idx %d\n", req, bio, bvec,
 968                                            seg_idx, databuf_idx);
 969
 970                                 /* Get a new storvsc request */
 971                                 /* 1st-time */
 972                                 if ((!blkvsc_req) ||
 973                                     (databuf_idx >= MAX_MULTIPAGE_BUFFER_COUNT)
 974                                     /* hole at the begin of page */
 975                                     || (bvec->bv_offset != 0) ||
 976                                     /* hold at the end of page */
 977                                     (prev_bvec &&
 978                                      (prev_bvec->bv_len != PAGE_SIZE))) {
 979                                         /* submit the prev one */
 980                                         if (blkvsc_req) {
 981                                                 blkvsc_req->sector_start = start_sector;
 982                                                 sector_div(blkvsc_req->sector_start, (blkdev->sector_size >> 9));
 983
 984                                                 blkvsc_req->sector_count = num_sectors / (blkdev->sector_size >> 9);
 985                                                 blkvsc_init_rw(blkvsc_req);
 986                                         }
 987
 988                                         /*
 989                                          * Create new blkvsc_req to represent
 990                                          * the current bvec
 991                                          */
 992                                         blkvsc_req = kmem_cache_alloc(blkdev->request_pool, GFP_ATOMIC);
 993                                         if (!blkvsc_req) {
 994                                                 /* free up everything */
 995                                                 list_for_each_entry_safe(
 996                                                         blkvsc_req, tmp,
 997                                                         &group->blkvsc_req_list,
 998                                                         req_entry) {
 999                                                         list_del(&blkvsc_req->req_entry);
1000                                                         kmem_cache_free(blkdev->request_pool, blkvsc_req);
1001                                                 }
1002
1003                                                 kmem_cache_free(blkdev->request_pool, group);
1004                                                 return -ENOMEM;
1005                                         }
1006
1007                                         memset(blkvsc_req, 0,
1008                                                sizeof(struct blkvsc_request));
1009
1010                                         blkvsc_req->dev = blkdev;
1011                                         blkvsc_req->req = req;
1012                                         blkvsc_req->request.DataBuffer.Offset = bvec->bv_offset;
1013                                         blkvsc_req->request.DataBuffer.Length = 0;
1014
1015                                         /* Add to the group */
1016                                         blkvsc_req->group = group;
1017                                         blkvsc_req->group->outstanding++;
1018                                         list_add_tail(&blkvsc_req->req_entry,
1019                                                 &blkvsc_req->group->blkvsc_req_list);
1020
1021                                         start_sector += num_sectors;
1022                                         num_sectors = 0;
1023                                         databuf_idx = 0;
1024                                 }
1025
1026                                 /* Add the curr bvec/segment to the curr blkvsc_req */
1027                                 blkvsc_req->request.DataBuffer.PfnArray[databuf_idx] = page_to_pfn(bvec->bv_page);
1028                                 blkvsc_req->request.DataBuffer.Length += bvec->bv_len;
1029
1030                                 prev_bvec = bvec;
1031
1032                                 databuf_idx++;
1033                                 num_sectors += bvec->bv_len >> 9;
1034
1035                         } /* bio_for_each_segment */
1036
1037                 } /* rq_for_each_bio */
1038         }
1039
1040         /* Handle the last one */
1041         if (blkvsc_req) {
1042                 DPRINT_DBG(BLKVSC_DRV, "blkdev %p req %p group %p count %d\n",
1043                            blkdev, req, blkvsc_req->group,
1044                            blkvsc_req->group->outstanding);
1045
1046                 blkvsc_req->sector_start = start_sector;
1047                 sector_div(blkvsc_req->sector_start,
1048                            (blkdev->sector_size >> 9));
1049
1050                 blkvsc_req->sector_count = num_sectors /
1051                                            (blkdev->sector_size >> 9);
1052
1053                 blkvsc_init_rw(blkvsc_req);
1054         }
1055
1056         list_for_each_entry(blkvsc_req, &group->blkvsc_req_list, req_entry) {
1057                 if (pending) {
1058                         DPRINT_DBG(BLKVSC_DRV, "adding blkvsc_req to "
1059                                    "pending_list - blkvsc_req %p start_sect %lu"
1060                                    " sect_count %ld (%lu %ld)\n", blkvsc_req,
1061                                    (unsigned long)blkvsc_req->sector_start,
1062                                    blkvsc_req->sector_count,
1063                                    (unsigned long)start_sector,
1064                                    (unsigned long)num_sectors);
1065
1066                         list_add_tail(&blkvsc_req->pend_entry,
1067                                       &blkdev->pending_list);
1068                 } else {
1069                         ret = blkvsc_submit_request(blkvsc_req,
1070                                                     blkvsc_request_completion);
1071                         if (ret == -1) {
1072                                 pending = 1;
1073                                 list_add_tail(&blkvsc_req->pend_entry,
1074                                               &blkdev->pending_list);
1075                         }
1076
1077                         DPRINT_DBG(BLKVSC_DRV, "submitted blkvsc_req %p "
1078                                    "start_sect %lu sect_count %ld (%lu %ld) "
1079                                    "ret %d\n", blkvsc_req,
1080                                    (unsigned long)blkvsc_req->sector_start,
1081                                    blkvsc_req->sector_count,
1082                                    (unsigned long)start_sector,
1083                                    num_sectors, ret);
1084                 }
1085         }
1086
1087         return pending;
1088 }
1089
1090 static void blkvsc_cmd_completion(struct hv_storvsc_request *request)
1091 {
1092         struct blkvsc_request *blkvsc_req =
1093                         (struct blkvsc_request *)request->Context;
1094         struct block_device_context *blkdev =
1095                         (struct block_device_context *)blkvsc_req->dev;
1096         struct scsi_sense_hdr sense_hdr;
1097
1098         DPRINT_DBG(BLKVSC_DRV, "blkvsc_cmd_completion() - req %p\n",
1099                    blkvsc_req);
1100
1101         blkdev->num_outstanding_reqs--;
1102
1103         if (blkvsc_req->request.Status)
1104                 if (scsi_normalize_sense(blkvsc_req->sense_buffer,
1105                                          SCSI_SENSE_BUFFERSIZE, &sense_hdr))
1106                         scsi_print_sense_hdr("blkvsc", &sense_hdr);
1107
1108         blkvsc_req->cond = 1;
1109         wake_up_interruptible(&blkvsc_req->wevent);
1110 }
1111
1112 static void blkvsc_request_completion(struct hv_storvsc_request *request)
1113 {
1114         struct blkvsc_request *blkvsc_req =
1115                         (struct blkvsc_request *)request->Context;
1116         struct block_device_context *blkdev =
1117                         (struct block_device_context *)blkvsc_req->dev;
1118         unsigned long flags;
1119         struct blkvsc_request *comp_req, *tmp;
1120
1121         ASSERT(blkvsc_req->group);
1122
1123         DPRINT_DBG(BLKVSC_DRV, "blkdev %p blkvsc_req %p group %p type %s "
1124                    "sect_start %lu sect_count %ld len %d group outstd %d "
1125                    "total outstd %d\n",
1126                    blkdev, blkvsc_req, blkvsc_req->group,
1127                    (blkvsc_req->write) ? "WRITE" : "READ",
1128                    (unsigned long)blkvsc_req->sector_start,
1129                    blkvsc_req->sector_count,
1130                    blkvsc_req->request.DataBuffer.Length,
1131                    blkvsc_req->group->outstanding,
1132                    blkdev->num_outstanding_reqs);
1133
1134         spin_lock_irqsave(&blkdev->lock, flags);
1135
1136         blkdev->num_outstanding_reqs--;
1137         blkvsc_req->group->outstanding--;
1138
1139         /*
1140          * Only start processing when all the blkvsc_reqs are
1141          * completed. This guarantees no out-of-order blkvsc_req
1142          * completion when calling end_that_request_first()
1143          */
1144         if (blkvsc_req->group->outstanding == 0) {
1145                 list_for_each_entry_safe(comp_req, tmp,
1146                                          &blkvsc_req->group->blkvsc_req_list,
1147                                          req_entry) {
1148                         DPRINT_DBG(BLKVSC_DRV, "completing blkvsc_req %p "
1149                                    "sect_start %lu sect_count %ld \n",
1150                                    comp_req,
1151                                    (unsigned long)comp_req->sector_start,
1152                                    comp_req->sector_count);
1153
1154                         list_del(&comp_req->req_entry);
1155
1156                         if (!__blk_end_request(comp_req->req,
1157                                 (!comp_req->request.Status ? 0 : -EIO),
1158                                 comp_req->sector_count * blkdev->sector_size)) {
1159                                 /*
1160                                  * All the sectors have been xferred ie the
1161                                  * request is done
1162                                  */
1163                                 DPRINT_DBG(BLKVSC_DRV, "req %p COMPLETED\n",
1164                                            comp_req->req);
1165                                 kmem_cache_free(blkdev->request_pool,
1166                                                 comp_req->group);
1167                         }
1168
1169                         kmem_cache_free(blkdev->request_pool, comp_req);
1170                 }
1171
1172                 if (!blkdev->shutting_down) {
1173                         blkvsc_do_pending_reqs(blkdev);
1174                         blk_start_queue(blkdev->gd->queue);
1175                         blkvsc_request(blkdev->gd->queue);
1176                 }
1177         }
1178
1179         spin_unlock_irqrestore(&blkdev->lock, flags);
1180 }
1181
1182 static int blkvsc_cancel_pending_reqs(struct block_device_context *blkdev)
1183 {
1184         struct blkvsc_request *pend_req, *tmp;
1185         struct blkvsc_request *comp_req, *tmp2;
1186
1187         int ret = 0;
1188
1189         DPRINT_DBG(BLKVSC_DRV, "blkvsc_cancel_pending_reqs()");
1190
1191         /* Flush the pending list first */
1192         list_for_each_entry_safe(pend_req, tmp, &blkdev->pending_list,
1193                                  pend_entry) {
1194                 /*
1195                  * The pend_req could be part of a partially completed
1196                  * request. If so, complete those req first until we
1197                  * hit the pend_req
1198                  */
1199                 list_for_each_entry_safe(comp_req, tmp2,
1200                                          &pend_req->group->blkvsc_req_list,
1201                                          req_entry) {
1202                         DPRINT_DBG(BLKVSC_DRV, "completing blkvsc_req %p "
1203                                    "sect_start %lu sect_count %ld \n",
1204                                    comp_req,
1205                                    (unsigned long) comp_req->sector_start,
1206                                    comp_req->sector_count);
1207
1208                         if (comp_req == pend_req)
1209                                 break;
1210
1211                         list_del(&comp_req->req_entry);
1212
1213                         if (comp_req->req) {
1214                                 ret = __blk_end_request(comp_req->req,
1215                                         (!comp_req->request.Status ? 0 : -EIO),
1216                                         comp_req->sector_count *
1217                                         blkdev->sector_size);
1218                                 ASSERT(ret != 0);
1219                         }
1220
1221                         kmem_cache_free(blkdev->request_pool, comp_req);
1222                 }
1223
1224                 DPRINT_DBG(BLKVSC_DRV, "cancelling pending request - %p\n",
1225                            pend_req);
1226
1227                 list_del(&pend_req->pend_entry);
1228
1229                 list_del(&pend_req->req_entry);
1230
1231                 if (comp_req->req) {
1232                         if (!__blk_end_request(pend_req->req, -EIO,
1233                                                pend_req->sector_count *
1234                                                blkdev->sector_size)) {
1235                                 /*
1236                                  * All the sectors have been xferred ie the
1237                                  * request is done
1238                                  */
1239                                 DPRINT_DBG(BLKVSC_DRV,
1240                                            "blkvsc_cancel_pending_reqs() - "
1241                                            "req %p COMPLETED\n", pend_req->req);
1242                                 kmem_cache_free(blkdev->request_pool,
1243                                                 pend_req->group);
1244                         }
1245                 }
1246
1247                 kmem_cache_free(blkdev->request_pool, pend_req);
1248         }
1249
1250         return ret;
1251 }
1252
1253 static int blkvsc_do_pending_reqs(struct block_device_context *blkdev)
1254 {
1255         struct blkvsc_request *pend_req, *tmp;
1256         int ret = 0;
1257
1258         /* Flush the pending list first */
1259         list_for_each_entry_safe(pend_req, tmp, &blkdev->pending_list,
1260                                  pend_entry) {
1261                 DPRINT_DBG(BLKVSC_DRV, "working off pending_list - %p\n",
1262                            pend_req);
1263
1264                 ret = blkvsc_submit_request(pend_req,
1265                                             blkvsc_request_completion);
1266                 if (ret != 0)
1267                         break;
1268                 else
1269                         list_del(&pend_req->pend_entry);
1270         }
1271
1272         return ret;
1273 }
1274
1275 static void blkvsc_request(struct request_queue *queue)
1276 {
1277         struct block_device_context *blkdev = NULL;
1278         struct request *req;
1279         int ret = 0;
1280
1281         DPRINT_DBG(BLKVSC_DRV, "- enter \n");
1282         while ((req = blk_peek_request(queue)) != NULL) {
1283                 DPRINT_DBG(BLKVSC_DRV, "- req %p\n", req);
1284
1285                 blkdev = req->rq_disk->private_data;
1286                 if (blkdev->shutting_down || !blk_fs_request(req) ||
1287                     blkdev->media_not_present) {
1288                         __blk_end_request_cur(req, 0);
1289                         continue;
1290                 }
1291
1292                 ret = blkvsc_do_pending_reqs(blkdev);
1293
1294                 if (ret != 0) {
1295                         DPRINT_DBG(BLKVSC_DRV,
1296                                    "- stop queue - pending_list not empty\n");
1297                         blk_stop_queue(queue);
1298                         break;
1299                 }
1300
1301                 blk_start_request(req);
1302
1303                 ret = blkvsc_do_request(blkdev, req);
1304                 if (ret > 0) {
1305                         DPRINT_DBG(BLKVSC_DRV, "- stop queue - no room\n");
1306                         blk_stop_queue(queue);
1307                         break;
1308                 } else if (ret < 0) {
1309                         DPRINT_DBG(BLKVSC_DRV, "- stop queue - no mem\n");
1310                         blk_requeue_request(queue, req);
1311                         blk_stop_queue(queue);
1312                         break;
1313                 }
1314         }
1315 }
1316
1317 static int blkvsc_open(struct block_device *bdev, fmode_t mode)
1318 {
1319         struct block_device_context *blkdev = bdev->bd_disk->private_data;
1320
1321         DPRINT_DBG(BLKVSC_DRV, "- users %d disk %s\n", blkdev->users,
1322                    blkdev->gd->disk_name);
1323
1324         spin_lock(&blkdev->lock);
1325
1326         if (!blkdev->users && blkdev->device_type == DVD_TYPE) {
1327                 spin_unlock(&blkdev->lock);
1328                 check_disk_change(bdev);
1329                 spin_lock(&blkdev->lock);
1330         }
1331
1332         blkdev->users++;
1333
1334         spin_unlock(&blkdev->lock);
1335         return 0;
1336 }
1337
1338 static int blkvsc_release(struct gendisk *disk, fmode_t mode)
1339 {
1340         struct block_device_context *blkdev = disk->private_data;
1341
1342         DPRINT_DBG(BLKVSC_DRV, "- users %d disk %s\n", blkdev->users,
1343                    blkdev->gd->disk_name);
1344
1345         spin_lock(&blkdev->lock);
1346         if (blkdev->users == 1) {
1347                 spin_unlock(&blkdev->lock);
1348                 blkvsc_do_flush(blkdev);
1349                 spin_lock(&blkdev->lock);
1350         }
1351
1352         blkdev->users--;
1353
1354         spin_unlock(&blkdev->lock);
1355         return 0;
1356 }
1357
1358 static int blkvsc_media_changed(struct gendisk *gd)
1359 {
1360         DPRINT_DBG(BLKVSC_DRV, "- enter\n");
1361         return 1;
1362 }
1363
1364 static int blkvsc_revalidate_disk(struct gendisk *gd)
1365 {
1366         struct block_device_context *blkdev = gd->private_data;
1367
1368         DPRINT_DBG(BLKVSC_DRV, "- enter\n");
1369
1370         if (blkdev->device_type == DVD_TYPE) {
1371                 blkvsc_do_read_capacity(blkdev);
1372                 set_capacity(blkdev->gd, blkdev->capacity *
1373                             (blkdev->sector_size/512));
1374                 blk_queue_logical_block_size(gd->queue, blkdev->sector_size);
1375         }
1376         return 0;
1377 }
1378
1379 static int blkvsc_getgeo(struct block_device *bd, struct hd_geometry *hg)
1380 {
1381         sector_t total_sectors = get_capacity(bd->bd_disk);
1382         sector_t cylinder_times_heads = 0;
1383         sector_t temp = 0;
1384
1385         int sectors_per_track = 0;
1386         int heads = 0;
1387         int cylinders = 0;
1388         int rem = 0;
1389
1390         if (total_sectors > (65535 * 16 * 255))
1391                 total_sectors = (65535 * 16 * 255);
1392
1393         if (total_sectors >= (65535 * 16 * 63)) {
1394                 sectors_per_track = 255;
1395                 heads = 16;
1396
1397                 cylinder_times_heads = total_sectors;
1398                 /* sector_div stores the quotient in cylinder_times_heads */
1399                 rem = sector_div(cylinder_times_heads, sectors_per_track);
1400         } else {
1401                 sectors_per_track = 17;
1402
1403                 cylinder_times_heads = total_sectors;
1404                 /* sector_div stores the quotient in cylinder_times_heads */
1405                 rem = sector_div(cylinder_times_heads, sectors_per_track);
1406
1407                 temp = cylinder_times_heads + 1023;
1408                 /* sector_div stores the quotient in temp */
1409                 rem = sector_div(temp, 1024);
1410
1411                 heads = temp;
1412
1413                 if (heads < 4)
1414                         heads = 4;
1415
1416
1417                 if (cylinder_times_heads >= (heads * 1024) || (heads > 16)) {
1418                         sectors_per_track = 31;
1419                         heads = 16;
1420
1421                         cylinder_times_heads = total_sectors;
1422                         /*
1423                          * sector_div stores the quotient in
1424                          * cylinder_times_heads
1425                          */
1426                         rem = sector_div(cylinder_times_heads,
1427                                          sectors_per_track);
1428                 }
1429
1430                 if (cylinder_times_heads >= (heads * 1024)) {
1431                         sectors_per_track = 63;
1432                         heads = 16;
1433
1434                         cylinder_times_heads = total_sectors;
1435                         /*
1436                          * sector_div stores the quotient in
1437                          * cylinder_times_heads
1438                          */
1439                         rem = sector_div(cylinder_times_heads,
1440                                          sectors_per_track);
1441                 }
1442         }
1443
1444         temp = cylinder_times_heads;
1445         /* sector_div stores the quotient in temp */
1446         rem = sector_div(temp, heads);
1447         cylinders = temp;
1448
1449         hg->heads = heads;
1450         hg->sectors = sectors_per_track;
1451         hg->cylinders = cylinders;
1452
1453         DPRINT_INFO(BLKVSC_DRV, "CHS (%d, %d, %d)", cylinders, heads,
1454                     sectors_per_track);
1455
1456     return 0;
1457 }
1458
1459 static int blkvsc_ioctl(struct block_device *bd, fmode_t mode,
1460                         unsigned cmd, unsigned long argument)
1461 {
1462 /*      struct block_device_context *blkdev = bd->bd_disk->private_data; */
1463         int ret;
1464
1465         switch (cmd) {
1466         /*
1467          * TODO: I think there is certain format for HDIO_GET_IDENTITY rather
1468          * than just a GUID. Commented it out for now.
1469          */
1470 #if 0
1471         case HDIO_GET_IDENTITY:
1472                 DPRINT_INFO(BLKVSC_DRV, "HDIO_GET_IDENTITY\n");
1473                 if (copy_to_user((void __user *)arg, blkdev->device_id,
1474                                  blkdev->device_id_len))
1475                         ret = -EFAULT;
1476                 break;
1477 #endif
1478         default:
1479                 ret = -EINVAL;
1480                 break;
1481         }
1482
1483         return ret;
1484 }
1485
1486 static int __init blkvsc_init(void)
1487 {
1488         int ret;
1489
1490         ASSERT(sizeof(sector_t) == 8); /* Make sure CONFIG_LBD is set */
1491
1492         DPRINT_ENTER(BLKVSC_DRV);
1493
1494         DPRINT_INFO(BLKVSC_DRV, "Blkvsc initializing....");
1495
1496         ret = blkvsc_drv_init(BlkVscInitialize);
1497
1498         DPRINT_EXIT(BLKVSC_DRV);
1499
1500         return ret;
1501 }
1502
1503 static void __exit blkvsc_exit(void)
1504 {
1505         DPRINT_ENTER(BLKVSC_DRV);
1506         blkvsc_drv_exit();
1507         DPRINT_ENTER(BLKVSC_DRV);
1508 }
1509
1510 MODULE_LICENSE("GPL");
1511 MODULE_VERSION(HV_DRV_VERSION);
1512 module_param(blkvsc_ringbuffer_size, int, S_IRUGO);
1513 module_init(blkvsc_init);
1514 module_exit(blkvsc_exit);