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 <linux/smp_lock.h>
  29 #include <linux/slab.h>
  30 #include <scsi/scsi.h>
  31 #include <scsi/scsi_cmnd.h>
  32 #include <scsi/scsi_eh.h>
  33 #include <scsi/scsi_dbg.h>
  34 #include "osd.h"
  35 #include "logging.h"
  36 #include "version_info.h"
  37 #include "vmbus.h"
  38 #include "storvsc_api.h"
  39
  40
  41 #define BLKVSC_MINORS   64
  42
  43 enum blkvsc_device_type {
  44         UNKNOWN_DEV_TYPE,
  45         HARDDISK_TYPE,
  46         DVD_TYPE,
  47 };
  48
  49 /*
  50  * This request ties the struct request and struct
  51  * blkvsc_request/hv_storvsc_request together A struct request may be
  52  * represented by 1 or more struct blkvsc_request
  53  */
  54 struct blkvsc_request_group {
  55         int outstanding;
  56         int status;
  57         struct list_head blkvsc_req_list;       /* list of blkvsc_requests */
  58 };
  59
  60 struct blkvsc_request {
  61         /* blkvsc_request_group.blkvsc_req_list */
  62         struct list_head req_entry;
  63
  64         /* block_device_context.pending_list */
  65         struct list_head pend_entry;
  66
  67         /* This may be null if we generate a request internally */
  68         struct request *req;
  69
  70         struct block_device_context *dev;
  71
  72         /* The group this request is part of. Maybe null */
  73         struct blkvsc_request_group *group;
  74
  75         wait_queue_head_t wevent;
  76         int cond;
  77
  78         int write;
  79         sector_t sector_start;
  80         unsigned long sector_count;
  81
  82         unsigned char sense_buffer[SCSI_SENSE_BUFFERSIZE];
  83         unsigned char cmd_len;
  84         unsigned char cmnd[MAX_COMMAND_SIZE];
  85
  86         struct hv_storvsc_request request;
  87         /*
  88          * !!!DO NOT ADD ANYTHING BELOW HERE!!! Otherwise, memory can overlap,
  89          * because - The extension buffer falls right here and is pointed to by
  90          * request.Extension;
  91          * Which sounds like a horrible idea, who designed this?
  92          */
  93 };
  94
  95 /* Per device structure */
  96 struct block_device_context {
  97         /* point back to our device context */
  98         struct vm_device *device_ctx;
  99         struct kmem_cache *request_pool;
 100         spinlock_t lock;
 101         struct gendisk *gd;
 102         enum blkvsc_device_type device_type;
 103         struct list_head pending_list;
 104
 105         unsigned char device_id[64];
 106         unsigned int device_id_len;
 107         int num_outstanding_reqs;
 108         int shutting_down;
 109         int media_not_present;
 110         unsigned int sector_size;
 111         sector_t capacity;
 112         unsigned int port;
 113         unsigned char path;
 114         unsigned char target;
 115         int users;
 116 };
 117
 118 /* Per driver */
 119 struct blkvsc_driver_context {
 120         /* !! These must be the first 2 fields !! */
 121         /* FIXME this is a bug! */
 122         struct driver_context drv_ctx;
 123         struct storvsc_driver_object drv_obj;
 124 };
 125
 126 /* Static decl */
 127 static int blkvsc_probe(struct device *dev);
 128 static int blkvsc_remove(struct device *device);
 129 static void blkvsc_shutdown(struct device *device);
 130
 131 static int blkvsc_open(struct block_device *bdev,  fmode_t mode);
 132 static int blkvsc_release(struct gendisk *disk, fmode_t mode);
 133 static int blkvsc_media_changed(struct gendisk *gd);
 134 static int blkvsc_revalidate_disk(struct gendisk *gd);
 135 static int blkvsc_getgeo(struct block_device *bd, struct hd_geometry *hg);
 136 static int blkvsc_ioctl(struct block_device *bd, fmode_t mode,
 137                         unsigned cmd, unsigned long argument);
 138 static void blkvsc_request(struct request_queue *queue);
 139 static void blkvsc_request_completion(struct hv_storvsc_request *request);
 140 static int blkvsc_do_request(struct block_device_context *blkdev,
 141                              struct request *req);
 142 static int blkvsc_submit_request(struct blkvsc_request *blkvsc_req,
 143                 void (*request_completion)(struct hv_storvsc_request *));
 144 static void blkvsc_init_rw(struct blkvsc_request *blkvsc_req);
 145 static void blkvsc_cmd_completion(struct hv_storvsc_request *request);
 146 static int blkvsc_do_inquiry(struct block_device_context *blkdev);
 147 static int blkvsc_do_read_capacity(struct block_device_context *blkdev);
 148 static int blkvsc_do_read_capacity16(struct block_device_context *blkdev);
 149 static int blkvsc_do_flush(struct block_device_context *blkdev);
 150 static int blkvsc_cancel_pending_reqs(struct block_device_context *blkdev);
 151 static int blkvsc_do_pending_reqs(struct block_device_context *blkdev);
 152
 153 static int blkvsc_ringbuffer_size = BLKVSC_RING_BUFFER_SIZE;
 154 module_param(blkvsc_ringbuffer_size, int, S_IRUGO);
 155 MODULE_PARM_DESC(ring_size, "Ring buffer size (in bytes)");
 156
 157 /* The one and only one */
 158 static struct blkvsc_driver_context g_blkvsc_drv;
 159
 160 static const struct block_device_operations block_ops = {
 161         .owner = THIS_MODULE,
 162         .open = blkvsc_open,
 163         .release = blkvsc_release,
 164         .media_changed = blkvsc_media_changed,
 165         .revalidate_disk = blkvsc_revalidate_disk,
 166         .getgeo = blkvsc_getgeo,
 167         .ioctl  = blkvsc_ioctl,
 168 };
 169
 170 /*
 171  * blkvsc_drv_init -  BlkVsc driver initialization.
 172  */
 173 static int blkvsc_drv_init(int (*drv_init)(struct hv_driver *drv))
 174 {
 175         struct storvsc_driver_object *storvsc_drv_obj = &g_blkvsc_drv.drv_obj;
 176         struct driver_context *drv_ctx = &g_blkvsc_drv.drv_ctx;
 177         int ret;
 178
 179         DPRINT_ENTER(BLKVSC_DRV);
 180
 181         vmbus_get_interface(&storvsc_drv_obj->Base.VmbusChannelInterface);
 182
 183         storvsc_drv_obj->RingBufferSize = blkvsc_ringbuffer_size;
 184
 185         /* Callback to client driver to complete the initialization */
 186         drv_init(&storvsc_drv_obj->Base);
 187
 188         drv_ctx->driver.name = storvsc_drv_obj->Base.name;
 189         memcpy(&drv_ctx->class_id, &storvsc_drv_obj->Base.deviceType,
 190                sizeof(struct hv_guid));
 191
 192         drv_ctx->probe = blkvsc_probe;
 193         drv_ctx->remove = blkvsc_remove;
 194         drv_ctx->shutdown = blkvsc_shutdown;
 195
 196         /* The driver belongs to vmbus */
 197         ret = vmbus_child_driver_register(drv_ctx);
 198
 199         DPRINT_EXIT(BLKVSC_DRV);
 200
 201         return ret;
 202 }
 203
 204 static int blkvsc_drv_exit_cb(struct device *dev, void *data)
 205 {
 206         struct device **curr = (struct device **)data;
 207         *curr = dev;
 208         return 1; /* stop iterating */
 209 }
 210
 211 static void blkvsc_drv_exit(void)
 212 {
 213         struct storvsc_driver_object *storvsc_drv_obj = &g_blkvsc_drv.drv_obj;
 214         struct driver_context *drv_ctx = &g_blkvsc_drv.drv_ctx;
 215         struct device *current_dev;
 216         int ret;
 217
 218         DPRINT_ENTER(BLKVSC_DRV);
 219
 220         while (1) {
 221                 current_dev = NULL;
 222
 223                 /* Get the device */
 224                 ret = driver_for_each_device(&drv_ctx->driver, NULL,
 225                                              (void *) &current_dev,
 226                                              blkvsc_drv_exit_cb);
 227
 228                 if (ret)
 229                         DPRINT_WARN(BLKVSC_DRV,
 230                                     "driver_for_each_device returned %d", ret);
 231
 232
 233                 if (current_dev == NULL)
 234                         break;
 235
 236                 /* Initiate removal from the top-down */
 237                 device_unregister(current_dev);
 238         }
 239
 240         if (storvsc_drv_obj->Base.OnCleanup)
 241                 storvsc_drv_obj->Base.OnCleanup(&storvsc_drv_obj->Base);
 242
 243         vmbus_child_driver_unregister(drv_ctx);
 244
 245         DPRINT_EXIT(BLKVSC_DRV);
 246
 247         return;
 248 }
 249
 250 /*
 251  * blkvsc_probe - Add a new device for this driver
 252  */
 253 static int blkvsc_probe(struct device *device)
 254 {
 255         struct driver_context *driver_ctx =
 256                                 driver_to_driver_context(device->driver);
 257         struct blkvsc_driver_context *blkvsc_drv_ctx =
 258                                 (struct blkvsc_driver_context *)driver_ctx;
 259         struct storvsc_driver_object *storvsc_drv_obj =
 260                                 &blkvsc_drv_ctx->drv_obj;
 261         struct vm_device *device_ctx = device_to_vm_device(device);
 262         struct hv_device *device_obj = &device_ctx->device_obj;
 263
 264         struct block_device_context *blkdev = NULL;
 265         struct storvsc_device_info device_info;
 266         int major = 0;
 267         int devnum = 0;
 268         int ret = 0;
 269         static int ide0_registered;
 270         static int ide1_registered;
 271
 272         DPRINT_ENTER(BLKVSC_DRV);
 273
 274         DPRINT_DBG(BLKVSC_DRV, "blkvsc_probe - enter");
 275
 276         if (!storvsc_drv_obj->Base.OnDeviceAdd) {
 277                 DPRINT_ERR(BLKVSC_DRV, "OnDeviceAdd() not set");
 278                 ret = -1;
 279                 goto Cleanup;
 280         }
 281
 282         blkdev = kzalloc(sizeof(struct block_device_context), GFP_KERNEL);
 283         if (!blkdev) {
 284                 ret = -ENOMEM;
 285                 goto Cleanup;
 286         }
 287
 288         INIT_LIST_HEAD(&blkdev->pending_list);
 289
 290         /* Initialize what we can here */
 291         spin_lock_init(&blkdev->lock);
 292
 293         /* ASSERT(sizeof(struct blkvsc_request_group) <= */
 294         /*      sizeof(struct blkvsc_request)); */
 295
 296         blkdev->request_pool = kmem_cache_create(dev_name(&device_ctx->device),
 297                                         sizeof(struct blkvsc_request) +
 298                                         storvsc_drv_obj->RequestExtSize, 0,
 299                                         SLAB_HWCACHE_ALIGN, NULL);
 300         if (!blkdev->request_pool) {
 301                 ret = -ENOMEM;
 302                 goto Cleanup;
 303         }
 304
 305
 306         /* Call to the vsc driver to add the device */
 307         ret = storvsc_drv_obj->Base.OnDeviceAdd(device_obj, &device_info);
 308         if (ret != 0) {
 309                 DPRINT_ERR(BLKVSC_DRV, "unable to add blkvsc device");
 310                 goto Cleanup;
 311         }
 312
 313         blkdev->device_ctx = device_ctx;
 314         /* this identified the device 0 or 1 */
 315         blkdev->target = device_info.TargetId;
 316         /* this identified the ide ctrl 0 or 1 */
 317         blkdev->path = device_info.PathId;
 318
 319         dev_set_drvdata(device, blkdev);
 320
 321         /* Calculate the major and device num */
 322         if (blkdev->path == 0) {
 323                 major = IDE0_MAJOR;
 324                 devnum = blkdev->path + blkdev->target;         /* 0 or 1 */
 325
 326                 if (!ide0_registered) {
 327                         ret = register_blkdev(major, "ide");
 328                         if (ret != 0) {
 329                                 DPRINT_ERR(BLKVSC_DRV,
 330                                            "register_blkdev() failed! ret %d",
 331                                            ret);
 332                                 goto Remove;
 333                         }
 334
 335                         ide0_registered = 1;
 336                 }
 337         } else if (blkdev->path == 1) {
 338                 major = IDE1_MAJOR;
 339                 devnum = blkdev->path + blkdev->target + 1; /* 2 or 3 */
 340
 341                 if (!ide1_registered) {
 342                         ret = register_blkdev(major, "ide");
 343                         if (ret != 0) {
 344                                 DPRINT_ERR(BLKVSC_DRV,
 345                                            "register_blkdev() failed! ret %d",
 346                                            ret);
 347                                 goto Remove;
 348                         }
 349
 350                         ide1_registered = 1;
 351                 }
 352         } else {
 353                 DPRINT_ERR(BLKVSC_DRV, "invalid pathid");
 354                 ret = -1;
 355                 goto Cleanup;
 356         }
 357
 358         DPRINT_INFO(BLKVSC_DRV, "blkvsc registered for major %d!!", major);
 359
 360         blkdev->gd = alloc_disk(BLKVSC_MINORS);
 361         if (!blkdev->gd) {
 362                 DPRINT_ERR(BLKVSC_DRV, "register_blkdev() failed! ret %d", ret);
 363                 ret = -1;
 364                 goto Cleanup;
 365         }
 366
 367         blkdev->gd->queue = blk_init_queue(blkvsc_request, &blkdev->lock);
 368
 369         blk_queue_max_segment_size(blkdev->gd->queue, PAGE_SIZE);
 370         blk_queue_max_segments(blkdev->gd->queue, 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 vm_device *device_ctx = device_to_vm_device(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] |=
 828                         (blkvsc_req->req->cmd_flags & REQ_FUA) ? 0x8 : 0;
 829
 830                 *(unsigned long long *)&blkvsc_req->cmnd[2] =
 831                                 cpu_to_be64(blkvsc_req->sector_start);
 832                 *(unsigned int *)&blkvsc_req->cmnd[10] =
 833                                 cpu_to_be32(blkvsc_req->sector_count);
 834         } else if ((blkvsc_req->sector_count > 0xff) ||
 835                    (blkvsc_req->sector_start > 0x1fffff)) {
 836                 if (rq_data_dir(blkvsc_req->req)) {
 837                         blkvsc_req->write = 1;
 838                         blkvsc_req->cmnd[0] = WRITE_10;
 839                 } else {
 840                         blkvsc_req->write = 0;
 841                         blkvsc_req->cmnd[0] = READ_10;
 842                 }
 843
 844                 blkvsc_req->cmnd[1] |=
 845                         (blkvsc_req->req->cmd_flags & REQ_FUA) ? 0x8 : 0;
 846
 847                 *(unsigned int *)&blkvsc_req->cmnd[2] =
 848                                 cpu_to_be32(blkvsc_req->sector_start);
 849                 *(unsigned short *)&blkvsc_req->cmnd[7] =
 850                                 cpu_to_be16(blkvsc_req->sector_count);
 851         } else {
 852                 if (rq_data_dir(blkvsc_req->req)) {
 853                         blkvsc_req->write = 1;
 854                         blkvsc_req->cmnd[0] = WRITE_6;
 855                 } else {
 856                         blkvsc_req->write = 0;
 857                         blkvsc_req->cmnd[0] = READ_6;
 858                 }
 859
 860                 *(unsigned int *)&blkvsc_req->cmnd[1] =
 861                                 cpu_to_be32(blkvsc_req->sector_start) >> 8;
 862                 blkvsc_req->cmnd[1] &= 0x1f;
 863                 blkvsc_req->cmnd[4] = (unsigned char)blkvsc_req->sector_count;
 864         }
 865 }
 866
 867 static int blkvsc_submit_request(struct blkvsc_request *blkvsc_req,
 868                         void (*request_completion)(struct hv_storvsc_request *))
 869 {
 870         struct block_device_context *blkdev = blkvsc_req->dev;
 871         struct vm_device *device_ctx = blkdev->device_ctx;
 872         struct driver_context *driver_ctx =
 873                         driver_to_driver_context(device_ctx->device.driver);
 874         struct blkvsc_driver_context *blkvsc_drv_ctx =
 875                         (struct blkvsc_driver_context *)driver_ctx;
 876         struct storvsc_driver_object *storvsc_drv_obj =
 877                         &blkvsc_drv_ctx->drv_obj;
 878         struct hv_storvsc_request *storvsc_req;
 879         int ret;
 880
 881         DPRINT_DBG(BLKVSC_DRV, "blkvsc_submit_request() - "
 882                    "req %p type %s start_sector %lu count %ld offset %d "
 883                    "len %d\n", blkvsc_req,
 884                    (blkvsc_req->write) ? "WRITE" : "READ",
 885                    (unsigned long) blkvsc_req->sector_start,
 886                    blkvsc_req->sector_count,
 887                    blkvsc_req->request.DataBuffer.Offset,
 888                    blkvsc_req->request.DataBuffer.Length);
 889 #if 0
 890         for (i = 0; i < (blkvsc_req->request.DataBuffer.Length >> 12); i++) {
 891                 DPRINT_DBG(BLKVSC_DRV, "blkvsc_submit_request() - "
 892                            "req %p pfn[%d] %llx\n",
 893                            blkvsc_req, i,
 894                            blkvsc_req->request.DataBuffer.PfnArray[i]);
 895         }
 896 #endif
 897
 898         storvsc_req = &blkvsc_req->request;
 899         storvsc_req->Extension = (void *)((unsigned long)blkvsc_req +
 900                                           sizeof(struct blkvsc_request));
 901
 902         storvsc_req->Type = blkvsc_req->write ? WRITE_TYPE : READ_TYPE;
 903
 904         storvsc_req->OnIOCompletion = request_completion;
 905         storvsc_req->Context = blkvsc_req;
 906
 907         storvsc_req->Host = blkdev->port;
 908         storvsc_req->Bus = blkdev->path;
 909         storvsc_req->TargetId = blkdev->target;
 910         storvsc_req->LunId = 0;  /* this is not really used at all */
 911
 912         storvsc_req->CdbLen = blkvsc_req->cmd_len;
 913         storvsc_req->Cdb = blkvsc_req->cmnd;
 914
 915         storvsc_req->SenseBuffer = blkvsc_req->sense_buffer;
 916         storvsc_req->SenseBufferSize = SCSI_SENSE_BUFFERSIZE;
 917
 918         ret = storvsc_drv_obj->OnIORequest(&blkdev->device_ctx->device_obj,
 919                                            &blkvsc_req->request);
 920         if (ret == 0)
 921                 blkdev->num_outstanding_reqs++;
 922
 923         return ret;
 924 }
 925
 926 /*
 927  * We break the request into 1 or more blkvsc_requests and submit
 928  * them.  If we cant submit them all, we put them on the
 929  * pending_list. The blkvsc_request() will work on the pending_list.
 930  */
 931 static int blkvsc_do_request(struct block_device_context *blkdev,
 932                              struct request *req)
 933 {
 934         struct bio *bio = NULL;
 935         struct bio_vec *bvec = NULL;
 936         struct bio_vec *prev_bvec = NULL;
 937         struct blkvsc_request *blkvsc_req = NULL;
 938         struct blkvsc_request *tmp;
 939         int databuf_idx = 0;
 940         int seg_idx = 0;
 941         sector_t start_sector;
 942         unsigned long num_sectors = 0;
 943         int ret = 0;
 944         int pending = 0;
 945         struct blkvsc_request_group *group = NULL;
 946
 947         DPRINT_DBG(BLKVSC_DRV, "blkdev %p req %p sect %lu\n", blkdev, req,
 948                   (unsigned long)blk_rq_pos(req));
 949
 950         /* Create a group to tie req to list of blkvsc_reqs */
 951         group = kmem_cache_alloc(blkdev->request_pool, GFP_ATOMIC);
 952         if (!group)
 953                 return -ENOMEM;
 954
 955         INIT_LIST_HEAD(&group->blkvsc_req_list);
 956         group->outstanding = group->status = 0;
 957
 958         start_sector = blk_rq_pos(req);
 959
 960         /* foreach bio in the request */
 961         if (req->bio) {
 962                 for (bio = req->bio; bio; bio = bio->bi_next) {
 963                         /*
 964                          * Map this bio into an existing or new storvsc request
 965                          */
 966                         bio_for_each_segment(bvec, bio, seg_idx) {
 967                                 DPRINT_DBG(BLKVSC_DRV, "bio_for_each_segment() "
 968                                            "- req %p bio %p bvec %p seg_idx %d "
 969                                            "databuf_idx %d\n", req, bio, bvec,
 970                                            seg_idx, databuf_idx);
 971
 972                                 /* Get a new storvsc request */
 973                                 /* 1st-time */
 974                                 if ((!blkvsc_req) ||
 975                                     (databuf_idx >= MAX_MULTIPAGE_BUFFER_COUNT)
 976                                     /* hole at the begin of page */
 977                                     || (bvec->bv_offset != 0) ||
 978                                     /* hold at the end of page */
 979                                     (prev_bvec &&
 980                                      (prev_bvec->bv_len != PAGE_SIZE))) {
 981                                         /* submit the prev one */
 982                                         if (blkvsc_req) {
 983                                                 blkvsc_req->sector_start = start_sector;
 984                                                 sector_div(blkvsc_req->sector_start, (blkdev->sector_size >> 9));
 985
 986                                                 blkvsc_req->sector_count = num_sectors / (blkdev->sector_size >> 9);
 987                                                 blkvsc_init_rw(blkvsc_req);
 988                                         }
 989
 990                                         /*
 991                                          * Create new blkvsc_req to represent
 992                                          * the current bvec
 993                                          */
 994                                         blkvsc_req = kmem_cache_alloc(blkdev->request_pool, GFP_ATOMIC);
 995                                         if (!blkvsc_req) {
 996                                                 /* free up everything */
 997                                                 list_for_each_entry_safe(
 998                                                         blkvsc_req, tmp,
 999                                                         &group->blkvsc_req_list,
1000                                                         req_entry) {
1001                                                         list_del(&blkvsc_req->req_entry);
1002                                                         kmem_cache_free(blkdev->request_pool, blkvsc_req);
1003                                                 }
1004
1005                                                 kmem_cache_free(blkdev->request_pool, group);
1006                                                 return -ENOMEM;
1007                                         }
1008
1009                                         memset(blkvsc_req, 0,
1010                                                sizeof(struct blkvsc_request));
1011
1012                                         blkvsc_req->dev = blkdev;
1013                                         blkvsc_req->req = req;
1014                                         blkvsc_req->request.DataBuffer.Offset = bvec->bv_offset;
1015                                         blkvsc_req->request.DataBuffer.Length = 0;
1016
1017                                         /* Add to the group */
1018                                         blkvsc_req->group = group;
1019                                         blkvsc_req->group->outstanding++;
1020                                         list_add_tail(&blkvsc_req->req_entry,
1021                                                 &blkvsc_req->group->blkvsc_req_list);
1022
1023                                         start_sector += num_sectors;
1024                                         num_sectors = 0;
1025                                         databuf_idx = 0;
1026                                 }
1027
1028                                 /* Add the curr bvec/segment to the curr blkvsc_req */
1029                                 blkvsc_req->request.DataBuffer.PfnArray[databuf_idx] = page_to_pfn(bvec->bv_page);
1030                                 blkvsc_req->request.DataBuffer.Length += bvec->bv_len;
1031
1032                                 prev_bvec = bvec;
1033
1034                                 databuf_idx++;
1035                                 num_sectors += bvec->bv_len >> 9;
1036
1037                         } /* bio_for_each_segment */
1038
1039                 } /* rq_for_each_bio */
1040         }
1041
1042         /* Handle the last one */
1043         if (blkvsc_req) {
1044                 DPRINT_DBG(BLKVSC_DRV, "blkdev %p req %p group %p count %d\n",
1045                            blkdev, req, blkvsc_req->group,
1046                            blkvsc_req->group->outstanding);
1047
1048                 blkvsc_req->sector_start = start_sector;
1049                 sector_div(blkvsc_req->sector_start,
1050                            (blkdev->sector_size >> 9));
1051
1052                 blkvsc_req->sector_count = num_sectors /
1053                                            (blkdev->sector_size >> 9);
1054
1055                 blkvsc_init_rw(blkvsc_req);
1056         }
1057
1058         list_for_each_entry(blkvsc_req, &group->blkvsc_req_list, req_entry) {
1059                 if (pending) {
1060                         DPRINT_DBG(BLKVSC_DRV, "adding blkvsc_req to "
1061                                    "pending_list - blkvsc_req %p start_sect %lu"
1062                                    " sect_count %ld (%lu %ld)\n", blkvsc_req,
1063                                    (unsigned long)blkvsc_req->sector_start,
1064                                    blkvsc_req->sector_count,
1065                                    (unsigned long)start_sector,
1066                                    (unsigned long)num_sectors);
1067
1068                         list_add_tail(&blkvsc_req->pend_entry,
1069                                       &blkdev->pending_list);
1070                 } else {
1071                         ret = blkvsc_submit_request(blkvsc_req,
1072                                                     blkvsc_request_completion);
1073                         if (ret == -1) {
1074                                 pending = 1;
1075                                 list_add_tail(&blkvsc_req->pend_entry,
1076                                               &blkdev->pending_list);
1077                         }
1078
1079                         DPRINT_DBG(BLKVSC_DRV, "submitted blkvsc_req %p "
1080                                    "start_sect %lu sect_count %ld (%lu %ld) "
1081                                    "ret %d\n", blkvsc_req,
1082                                    (unsigned long)blkvsc_req->sector_start,
1083                                    blkvsc_req->sector_count,
1084                                    (unsigned long)start_sector,
1085                                    num_sectors, ret);
1086                 }
1087         }
1088
1089         return pending;
1090 }
1091
1092 static void blkvsc_cmd_completion(struct hv_storvsc_request *request)
1093 {
1094         struct blkvsc_request *blkvsc_req =
1095                         (struct blkvsc_request *)request->Context;
1096         struct block_device_context *blkdev =
1097                         (struct block_device_context *)blkvsc_req->dev;
1098         struct scsi_sense_hdr sense_hdr;
1099
1100         DPRINT_DBG(BLKVSC_DRV, "blkvsc_cmd_completion() - req %p\n",
1101                    blkvsc_req);
1102
1103         blkdev->num_outstanding_reqs--;
1104
1105         if (blkvsc_req->request.Status)
1106                 if (scsi_normalize_sense(blkvsc_req->sense_buffer,
1107                                          SCSI_SENSE_BUFFERSIZE, &sense_hdr))
1108                         scsi_print_sense_hdr("blkvsc", &sense_hdr);
1109
1110         blkvsc_req->cond = 1;
1111         wake_up_interruptible(&blkvsc_req->wevent);
1112 }
1113
1114 static void blkvsc_request_completion(struct hv_storvsc_request *request)
1115 {
1116         struct blkvsc_request *blkvsc_req =
1117                         (struct blkvsc_request *)request->Context;
1118         struct block_device_context *blkdev =
1119                         (struct block_device_context *)blkvsc_req->dev;
1120         unsigned long flags;
1121         struct blkvsc_request *comp_req, *tmp;
1122
1123         /* ASSERT(blkvsc_req->group); */
1124
1125         DPRINT_DBG(BLKVSC_DRV, "blkdev %p blkvsc_req %p group %p type %s "
1126                    "sect_start %lu sect_count %ld len %d group outstd %d "
1127                    "total outstd %d\n",
1128                    blkdev, blkvsc_req, blkvsc_req->group,
1129                    (blkvsc_req->write) ? "WRITE" : "READ",
1130                    (unsigned long)blkvsc_req->sector_start,
1131                    blkvsc_req->sector_count,
1132                    blkvsc_req->request.DataBuffer.Length,
1133                    blkvsc_req->group->outstanding,
1134                    blkdev->num_outstanding_reqs);
1135
1136         spin_lock_irqsave(&blkdev->lock, flags);
1137
1138         blkdev->num_outstanding_reqs--;
1139         blkvsc_req->group->outstanding--;
1140
1141         /*
1142          * Only start processing when all the blkvsc_reqs are
1143          * completed. This guarantees no out-of-order blkvsc_req
1144          * completion when calling end_that_request_first()
1145          */
1146         if (blkvsc_req->group->outstanding == 0) {
1147                 list_for_each_entry_safe(comp_req, tmp,
1148                                          &blkvsc_req->group->blkvsc_req_list,
1149                                          req_entry) {
1150                         DPRINT_DBG(BLKVSC_DRV, "completing blkvsc_req %p "
1151                                    "sect_start %lu sect_count %ld\n",
1152                                    comp_req,
1153                                    (unsigned long)comp_req->sector_start,
1154                                    comp_req->sector_count);
1155
1156                         list_del(&comp_req->req_entry);
1157
1158                         if (!__blk_end_request(comp_req->req,
1159                                 (!comp_req->request.Status ? 0 : -EIO),
1160                                 comp_req->sector_count * blkdev->sector_size)) {
1161                                 /*
1162                                  * All the sectors have been xferred ie the
1163                                  * request is done
1164                                  */
1165                                 DPRINT_DBG(BLKVSC_DRV, "req %p COMPLETED\n",
1166                                            comp_req->req);
1167                                 kmem_cache_free(blkdev->request_pool,
1168                                                 comp_req->group);
1169                         }
1170
1171                         kmem_cache_free(blkdev->request_pool, comp_req);
1172                 }
1173
1174                 if (!blkdev->shutting_down) {
1175                         blkvsc_do_pending_reqs(blkdev);
1176                         blk_start_queue(blkdev->gd->queue);
1177                         blkvsc_request(blkdev->gd->queue);
1178                 }
1179         }
1180
1181         spin_unlock_irqrestore(&blkdev->lock, flags);
1182 }
1183
1184 static int blkvsc_cancel_pending_reqs(struct block_device_context *blkdev)
1185 {
1186         struct blkvsc_request *pend_req, *tmp;
1187         struct blkvsc_request *comp_req, *tmp2;
1188
1189         int ret = 0;
1190
1191         DPRINT_DBG(BLKVSC_DRV, "blkvsc_cancel_pending_reqs()");
1192
1193         /* Flush the pending list first */
1194         list_for_each_entry_safe(pend_req, tmp, &blkdev->pending_list,
1195                                  pend_entry) {
1196                 /*
1197                  * The pend_req could be part of a partially completed
1198                  * request. If so, complete those req first until we
1199                  * hit the pend_req
1200                  */
1201                 list_for_each_entry_safe(comp_req, tmp2,
1202                                          &pend_req->group->blkvsc_req_list,
1203                                          req_entry) {
1204                         DPRINT_DBG(BLKVSC_DRV, "completing blkvsc_req %p "
1205                                    "sect_start %lu sect_count %ld\n",
1206                                    comp_req,
1207                                    (unsigned long) comp_req->sector_start,
1208                                    comp_req->sector_count);
1209
1210                         if (comp_req == pend_req)
1211                                 break;
1212
1213                         list_del(&comp_req->req_entry);
1214
1215                         if (comp_req->req) {
1216                                 ret = __blk_end_request(comp_req->req,
1217                                         (!comp_req->request.Status ? 0 : -EIO),
1218                                         comp_req->sector_count *
1219                                         blkdev->sector_size);
1220
1221                                 /* FIXME: shouldn't this do more than return? */
1222                                 if (ret)
1223                                         goto out;
1224                         }
1225
1226                         kmem_cache_free(blkdev->request_pool, comp_req);
1227                 }
1228
1229                 DPRINT_DBG(BLKVSC_DRV, "cancelling pending request - %p\n",
1230                            pend_req);
1231
1232                 list_del(&pend_req->pend_entry);
1233
1234                 list_del(&pend_req->req_entry);
1235
1236                 if (comp_req->req) {
1237                         if (!__blk_end_request(pend_req->req, -EIO,
1238                                                pend_req->sector_count *
1239                                                blkdev->sector_size)) {
1240                                 /*
1241                                  * All the sectors have been xferred ie the
1242                                  * request is done
1243                                  */
1244                                 DPRINT_DBG(BLKVSC_DRV,
1245                                            "blkvsc_cancel_pending_reqs() - "
1246                                            "req %p COMPLETED\n", pend_req->req);
1247                                 kmem_cache_free(blkdev->request_pool,
1248                                                 pend_req->group);
1249                         }
1250                 }
1251
1252                 kmem_cache_free(blkdev->request_pool, pend_req);
1253         }
1254
1255 out:
1256         return ret;
1257 }
1258
1259 static int blkvsc_do_pending_reqs(struct block_device_context *blkdev)
1260 {
1261         struct blkvsc_request *pend_req, *tmp;
1262         int ret = 0;
1263
1264         /* Flush the pending list first */
1265         list_for_each_entry_safe(pend_req, tmp, &blkdev->pending_list,
1266                                  pend_entry) {
1267                 DPRINT_DBG(BLKVSC_DRV, "working off pending_list - %p\n",
1268                            pend_req);
1269
1270                 ret = blkvsc_submit_request(pend_req,
1271                                             blkvsc_request_completion);
1272                 if (ret != 0)
1273                         break;
1274                 else
1275                         list_del(&pend_req->pend_entry);
1276         }
1277
1278         return ret;
1279 }
1280
1281 static void blkvsc_request(struct request_queue *queue)
1282 {
1283         struct block_device_context *blkdev = NULL;
1284         struct request *req;
1285         int ret = 0;
1286
1287         DPRINT_DBG(BLKVSC_DRV, "- enter\n");
1288         while ((req = blk_peek_request(queue)) != NULL) {
1289                 DPRINT_DBG(BLKVSC_DRV, "- req %p\n", req);
1290
1291                 blkdev = req->rq_disk->private_data;
1292                 if (blkdev->shutting_down || req->cmd_type != REQ_TYPE_FS ||
1293                     blkdev->media_not_present) {
1294                         __blk_end_request_cur(req, 0);
1295                         continue;
1296                 }
1297
1298                 ret = blkvsc_do_pending_reqs(blkdev);
1299
1300                 if (ret != 0) {
1301                         DPRINT_DBG(BLKVSC_DRV,
1302                                    "- stop queue - pending_list not empty\n");
1303                         blk_stop_queue(queue);
1304                         break;
1305                 }
1306
1307                 blk_start_request(req);
1308
1309                 ret = blkvsc_do_request(blkdev, req);
1310                 if (ret > 0) {
1311                         DPRINT_DBG(BLKVSC_DRV, "- stop queue - no room\n");
1312                         blk_stop_queue(queue);
1313                         break;
1314                 } else if (ret < 0) {
1315                         DPRINT_DBG(BLKVSC_DRV, "- stop queue - no mem\n");
1316                         blk_requeue_request(queue, req);
1317                         blk_stop_queue(queue);
1318                         break;
1319                 }
1320         }
1321 }
1322
1323 static int blkvsc_open(struct block_device *bdev, fmode_t mode)
1324 {
1325         struct block_device_context *blkdev = bdev->bd_disk->private_data;
1326
1327         DPRINT_DBG(BLKVSC_DRV, "- users %d disk %s\n", blkdev->users,
1328                    blkdev->gd->disk_name);
1329
1330         lock_kernel();
1331         spin_lock(&blkdev->lock);
1332
1333         if (!blkdev->users && blkdev->device_type == DVD_TYPE) {
1334                 spin_unlock(&blkdev->lock);
1335                 check_disk_change(bdev);
1336                 spin_lock(&blkdev->lock);
1337         }
1338
1339         blkdev->users++;
1340
1341         spin_unlock(&blkdev->lock);
1342         unlock_kernel();
1343         return 0;
1344 }
1345
1346 static int blkvsc_release(struct gendisk *disk, fmode_t mode)
1347 {
1348         struct block_device_context *blkdev = disk->private_data;
1349
1350         DPRINT_DBG(BLKVSC_DRV, "- users %d disk %s\n", blkdev->users,
1351                    blkdev->gd->disk_name);
1352
1353         lock_kernel();
1354         spin_lock(&blkdev->lock);
1355         if (blkdev->users == 1) {
1356                 spin_unlock(&blkdev->lock);
1357                 blkvsc_do_flush(blkdev);
1358                 spin_lock(&blkdev->lock);
1359         }
1360
1361         blkdev->users--;
1362
1363         spin_unlock(&blkdev->lock);
1364         unlock_kernel();
1365         return 0;
1366 }
1367
1368 static int blkvsc_media_changed(struct gendisk *gd)
1369 {
1370         DPRINT_DBG(BLKVSC_DRV, "- enter\n");
1371         return 1;
1372 }
1373
1374 static int blkvsc_revalidate_disk(struct gendisk *gd)
1375 {
1376         struct block_device_context *blkdev = gd->private_data;
1377
1378         DPRINT_DBG(BLKVSC_DRV, "- enter\n");
1379
1380         if (blkdev->device_type == DVD_TYPE) {
1381                 blkvsc_do_read_capacity(blkdev);
1382                 set_capacity(blkdev->gd, blkdev->capacity *
1383                             (blkdev->sector_size/512));
1384                 blk_queue_logical_block_size(gd->queue, blkdev->sector_size);
1385         }
1386         return 0;
1387 }
1388
1389 static int blkvsc_getgeo(struct block_device *bd, struct hd_geometry *hg)
1390 {
1391         sector_t total_sectors = get_capacity(bd->bd_disk);
1392         sector_t cylinder_times_heads = 0;
1393         sector_t temp = 0;
1394
1395         int sectors_per_track = 0;
1396         int heads = 0;
1397         int cylinders = 0;
1398         int rem = 0;
1399
1400         if (total_sectors > (65535 * 16 * 255))
1401                 total_sectors = (65535 * 16 * 255);
1402
1403         if (total_sectors >= (65535 * 16 * 63)) {
1404                 sectors_per_track = 255;
1405                 heads = 16;
1406
1407                 cylinder_times_heads = total_sectors;
1408                 /* sector_div stores the quotient in cylinder_times_heads */
1409                 rem = sector_div(cylinder_times_heads, sectors_per_track);
1410         } else {
1411                 sectors_per_track = 17;
1412
1413                 cylinder_times_heads = total_sectors;
1414                 /* sector_div stores the quotient in cylinder_times_heads */
1415                 rem = sector_div(cylinder_times_heads, sectors_per_track);
1416
1417                 temp = cylinder_times_heads + 1023;
1418                 /* sector_div stores the quotient in temp */
1419                 rem = sector_div(temp, 1024);
1420
1421                 heads = temp;
1422
1423                 if (heads < 4)
1424                         heads = 4;
1425
1426
1427                 if (cylinder_times_heads >= (heads * 1024) || (heads > 16)) {
1428                         sectors_per_track = 31;
1429                         heads = 16;
1430
1431                         cylinder_times_heads = total_sectors;
1432                         /*
1433                          * sector_div stores the quotient in
1434                          * cylinder_times_heads
1435                          */
1436                         rem = sector_div(cylinder_times_heads,
1437                                          sectors_per_track);
1438                 }
1439
1440                 if (cylinder_times_heads >= (heads * 1024)) {
1441                         sectors_per_track = 63;
1442                         heads = 16;
1443
1444                         cylinder_times_heads = total_sectors;
1445                         /*
1446                          * sector_div stores the quotient in
1447                          * cylinder_times_heads
1448                          */
1449                         rem = sector_div(cylinder_times_heads,
1450                                          sectors_per_track);
1451                 }
1452         }
1453
1454         temp = cylinder_times_heads;
1455         /* sector_div stores the quotient in temp */
1456         rem = sector_div(temp, heads);
1457         cylinders = temp;
1458
1459         hg->heads = heads;
1460         hg->sectors = sectors_per_track;
1461         hg->cylinders = cylinders;
1462
1463         DPRINT_INFO(BLKVSC_DRV, "CHS (%d, %d, %d)", cylinders, heads,
1464                     sectors_per_track);
1465
1466     return 0;
1467 }
1468
1469 static int blkvsc_ioctl(struct block_device *bd, fmode_t mode,
1470                         unsigned cmd, unsigned long argument)
1471 {
1472 /*      struct block_device_context *blkdev = bd->bd_disk->private_data; */
1473         int ret;
1474
1475         switch (cmd) {
1476         /*
1477          * TODO: I think there is certain format for HDIO_GET_IDENTITY rather
1478          * than just a GUID. Commented it out for now.
1479          */
1480 #if 0
1481         case HDIO_GET_IDENTITY:
1482                 DPRINT_INFO(BLKVSC_DRV, "HDIO_GET_IDENTITY\n");
1483                 if (copy_to_user((void __user *)arg, blkdev->device_id,
1484                                  blkdev->device_id_len))
1485                         ret = -EFAULT;
1486                 break;
1487 #endif
1488         default:
1489                 ret = -EINVAL;
1490                 break;
1491         }
1492
1493         return ret;
1494 }
1495
1496 static int __init blkvsc_init(void)
1497 {
1498         int ret;
1499
1500         BUILD_BUG_ON(sizeof(sector_t) != 8);
1501
1502         DPRINT_ENTER(BLKVSC_DRV);
1503
1504         DPRINT_INFO(BLKVSC_DRV, "Blkvsc initializing....");
1505
1506         ret = blkvsc_drv_init(BlkVscInitialize);
1507
1508         DPRINT_EXIT(BLKVSC_DRV);
1509
1510         return ret;
1511 }
1512
1513 static void __exit blkvsc_exit(void)
1514 {
1515         DPRINT_ENTER(BLKVSC_DRV);
1516         blkvsc_drv_exit();
1517         DPRINT_ENTER(BLKVSC_DRV);
1518 }
1519
1520 MODULE_LICENSE("GPL");
1521 MODULE_VERSION(HV_DRV_VERSION);
1522 MODULE_DESCRIPTION("Microsoft Hyper-V virtual block driver");
1523 module_init(blkvsc_init);
1524 module_exit(blkvsc_exit);