SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/staging/hv/storvsc_drv.c

   1 /*
   2  *
   3  * Copyright (c) 2009, Microsoft Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  16  * Place - Suite 330, Boston, MA 02111-1307 USA.
  17  *
  18  * Authors:
  19  *   Haiyang Zhang <haiyangz@microsoft.com>
  20  *   Hank Janssen  <hjanssen@microsoft.com>
  21  *
  22  */
  23
  24 #include <linux/init.h>
  25 #include <linux/module.h>
  26 #include <linux/device.h>
  27 #include <linux/blkdev.h>
  28
  29 #include <scsi/scsi.h>
  30 #include <scsi/scsi_cmnd.h>
  31 #include <scsi/scsi_host.h>
  32 #include <scsi/scsi_device.h>
  33 #include <scsi/scsi_tcq.h>
  34 #include <scsi/scsi_eh.h>
  35 #include <scsi/scsi_devinfo.h>
  36
  37 #include <scsi/scsi_dbg.h>
  38
  39 #include "osd.h"
  40 #include "include/logging.h"
  41 #include "vmbus.h"
  42 #include "include/StorVscApi.h"
  43
  44
  45 /* #defines */
  46
  47
  48
  49 /* Data types */
  50
  51 struct host_device_context {
  52     struct work_struct          host_rescan_work;  /* must be 1st field */
  53     struct device_context       *device_ctx; /* point back to our device context */
  54     struct kmem_cache               *request_pool;
  55     unsigned int                        port;
  56     unsigned char                       path;
  57     unsigned char                       target;
  58 };
  59
  60 struct storvsc_cmd_request {
  61         struct list_head        entry;
  62         struct scsi_cmnd        *cmd;
  63
  64         unsigned int bounce_sgl_count;
  65         struct scatterlist      *bounce_sgl;
  66
  67         struct hv_storvsc_request request;
  68         /* !!!DO NOT ADD ANYTHING BELOW HERE!!! */
  69         /* The extension buffer falls right here and is pointed to by request.Extension; */
  70 };
  71
  72 struct storvsc_driver_context {
  73         /* !! These must be the first 2 fields !! */
  74         struct driver_context   drv_ctx;
  75         struct storvsc_driver_object drv_obj;
  76 };
  77
  78 /* Static decl */
  79 static int storvsc_probe(struct device *dev);
  80 static int storvsc_queuecommand(struct scsi_cmnd *scmnd, void (*done)(struct scsi_cmnd *));
  81 static int storvsc_device_alloc(struct scsi_device *);
  82 static int storvsc_device_configure(struct scsi_device *);
  83 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd);
  84 static void storvsc_host_rescan_callback(struct work_struct *work);
  85 static void storvsc_host_rescan(struct hv_device* device_obj);
  86 static int storvsc_remove(struct device *dev);
  87
  88 static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count, unsigned int len);
  89 static void destroy_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count);
  90 static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count);
  91 static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl, struct scatterlist *bounce_sgl, unsigned int orig_sgl_count);
  92 static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl, struct scatterlist *bounce_sgl, unsigned int orig_sgl_count);
  93
  94 static int storvsc_report_luns(struct scsi_device *sdev, unsigned int luns[], unsigned int *lun_count);
  95 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev, sector_t capacity, int *info);
  96
  97
  98 static int storvsc_ringbuffer_size = STORVSC_RING_BUFFER_SIZE;
  99
 100 /* The one and only one */
 101 static struct storvsc_driver_context g_storvsc_drv;
 102
 103 /* Scsi driver */
 104 static struct scsi_host_template scsi_driver = {
 105         .module                                         = THIS_MODULE,
 106         .name                                           = "storvsc_host_t",
 107         .bios_param                                     = storvsc_get_chs,
 108         .queuecommand                           = storvsc_queuecommand,
 109         .eh_host_reset_handler          = storvsc_host_reset_handler,
 110         .slave_alloc                            = storvsc_device_alloc,
 111         .slave_configure                        = storvsc_device_configure,
 112         .cmd_per_lun                            = 1,
 113         .can_queue                                      = STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS, /* 64 max_queue * 1 target */
 114         .this_id                                        = -1,
 115         /* no use setting to 0 since ll_blk_rw reset it to 1 */
 116         .sg_tablesize                           = MAX_MULTIPAGE_BUFFER_COUNT,/* currently 32 */
 117         /* ENABLE_CLUSTERING allows mutiple physically contig bio_vecs to merge into 1 sg element. If set, we must */
 118         /* limit the max_segment_size to PAGE_SIZE, otherwise we may get 1 sg element that represents multiple */
 119         /* physically contig pfns (ie sg[x].length > PAGE_SIZE). */
 120         .use_clustering                         = ENABLE_CLUSTERING,
 121         /* Make sure we dont get a sg segment crosses a page boundary */
 122         .dma_boundary                           = PAGE_SIZE-1,
 123 };
 124
 125
 126 /*++
 127
 128 Name:   storvsc_drv_init()
 129
 130 Desc:   StorVsc driver initialization.
 131
 132 --*/
 133 static int storvsc_drv_init(PFN_DRIVERINITIALIZE pfn_drv_init)
 134 {
 135         int ret=0;
 136         struct storvsc_driver_object *storvsc_drv_obj = &g_storvsc_drv.drv_obj;
 137         struct driver_context *drv_ctx=&g_storvsc_drv.drv_ctx;
 138
 139         DPRINT_ENTER(STORVSC_DRV);
 140
 141         vmbus_get_interface(&storvsc_drv_obj->Base.VmbusChannelInterface);
 142
 143         storvsc_drv_obj->RingBufferSize = storvsc_ringbuffer_size;
 144         storvsc_drv_obj->OnHostRescan = storvsc_host_rescan;
 145
 146         /* Callback to client driver to complete the initialization */
 147         pfn_drv_init(&storvsc_drv_obj->Base);
 148
 149         DPRINT_INFO(STORVSC_DRV, "request extension size %u, max outstanding reqs %u", storvsc_drv_obj->RequestExtSize, storvsc_drv_obj->MaxOutstandingRequestsPerChannel);
 150
 151         if (storvsc_drv_obj->MaxOutstandingRequestsPerChannel < STORVSC_MAX_IO_REQUESTS)
 152         {
 153                 DPRINT_ERR(STORVSC_DRV, "The number of outstanding io requests (%d) is larger than that supported (%d) internally.",
 154                         STORVSC_MAX_IO_REQUESTS, storvsc_drv_obj->MaxOutstandingRequestsPerChannel);
 155                 return -1;
 156         }
 157
 158         drv_ctx->driver.name = storvsc_drv_obj->Base.name;
 159         memcpy(&drv_ctx->class_id, &storvsc_drv_obj->Base.deviceType, sizeof(struct hv_guid));
 160
 161         drv_ctx->probe = storvsc_probe;
 162         drv_ctx->remove = storvsc_remove;
 163
 164         /* The driver belongs to vmbus */
 165         ret = vmbus_child_driver_register(drv_ctx);
 166
 167         DPRINT_EXIT(STORVSC_DRV);
 168
 169         return ret;
 170 }
 171
 172
 173 static int storvsc_drv_exit_cb(struct device *dev, void *data)
 174 {
 175         struct device **curr = (struct device **)data;
 176         *curr = dev;
 177         return 1; /* stop iterating */
 178 }
 179
 180 /*++
 181
 182 Name:   storvsc_drv_exit()
 183
 184 Desc:
 185
 186 --*/
 187 static void storvsc_drv_exit(void)
 188 {
 189         struct storvsc_driver_object *storvsc_drv_obj = &g_storvsc_drv.drv_obj;
 190         struct driver_context *drv_ctx=&g_storvsc_drv.drv_ctx;
 191         struct device *current_dev=NULL;
 192         int ret;
 193
 194         DPRINT_ENTER(STORVSC_DRV);
 195
 196         while (1)
 197         {
 198                 current_dev = NULL;
 199
 200                 /* Get the device */
 201                 ret = driver_for_each_device(&drv_ctx->driver, NULL,
 202                                              (void *) &current_dev,
 203                                              storvsc_drv_exit_cb);
 204
 205                 if (ret)
 206                         DPRINT_WARN(STORVSC_DRV,
 207                                     "driver_for_each_device returned %d", ret);
 208
 209                 if (current_dev == NULL)
 210                         break;
 211
 212                 /* Initiate removal from the top-down */
 213                 device_unregister(current_dev);
 214         }
 215
 216         if (storvsc_drv_obj->Base.OnCleanup)
 217                 storvsc_drv_obj->Base.OnCleanup(&storvsc_drv_obj->Base);
 218
 219         vmbus_child_driver_unregister(drv_ctx);
 220
 221         DPRINT_EXIT(STORVSC_DRV);
 222
 223         return;
 224 }
 225
 226 /*++
 227
 228 Name:   storvsc_probe()
 229
 230 Desc:   Add a new device for this driver
 231
 232 --*/
 233 static int storvsc_probe(struct device *device)
 234 {
 235         int ret=0;
 236
 237         struct driver_context *driver_ctx = driver_to_driver_context(device->driver);
 238         struct storvsc_driver_context *storvsc_drv_ctx = (struct storvsc_driver_context*)driver_ctx;
 239         struct storvsc_driver_object *storvsc_drv_obj = &storvsc_drv_ctx->drv_obj;
 240
 241         struct device_context *device_ctx = device_to_device_context(device);
 242         struct hv_device *device_obj = &device_ctx->device_obj;
 243
 244         struct Scsi_Host *host;
 245         struct host_device_context *host_device_ctx;
 246         struct storvsc_device_info device_info;
 247
 248         DPRINT_ENTER(STORVSC_DRV);
 249
 250         if (!storvsc_drv_obj->Base.OnDeviceAdd)
 251                 return -1;
 252
 253         host = scsi_host_alloc(&scsi_driver, sizeof(struct host_device_context));
 254         if (!host)
 255         {
 256                 DPRINT_ERR(STORVSC_DRV, "unable to allocate scsi host object");
 257                 return -ENOMEM;
 258         }
 259
 260         dev_set_drvdata(device, host);
 261
 262         host_device_ctx = (struct host_device_context*)host->hostdata;
 263         memset(host_device_ctx, 0, sizeof(struct host_device_context));
 264
 265         host_device_ctx->port = host->host_no;
 266         host_device_ctx->device_ctx = device_ctx;
 267
 268         INIT_WORK(&host_device_ctx->host_rescan_work, storvsc_host_rescan_callback);
 269
 270         host_device_ctx->request_pool =
 271             kmem_cache_create
 272             (dev_name(&device_ctx->device),
 273              sizeof(struct storvsc_cmd_request) + storvsc_drv_obj->RequestExtSize,
 274              0,
 275              SLAB_HWCACHE_ALIGN, NULL);
 276
 277         if (!host_device_ctx->request_pool)
 278         {
 279                 scsi_host_put(host);
 280                 DPRINT_EXIT(STORVSC_DRV);
 281
 282                 return -ENOMEM;
 283         }
 284
 285         device_info.PortNumber = host->host_no;
 286         /* Call to the vsc driver to add the device */
 287         ret = storvsc_drv_obj->Base.OnDeviceAdd(device_obj, (void*)&device_info);
 288         if (ret != 0)
 289         {
 290                 DPRINT_ERR(STORVSC_DRV, "unable to add scsi vsc device");
 291                 kmem_cache_destroy(host_device_ctx->request_pool);
 292                 scsi_host_put(host);
 293                 DPRINT_EXIT(STORVSC_DRV);
 294
 295                 return -1;
 296         }
 297
 298         /* host_device_ctx->port = device_info.PortNumber; */
 299         host_device_ctx->path = device_info.PathId;
 300         host_device_ctx->target = device_info.TargetId;
 301
 302         host->max_lun = STORVSC_MAX_LUNS_PER_TARGET;    /* max # of devices per target */
 303         host->max_id = STORVSC_MAX_TARGETS;                     /* max # of targets per channel */
 304         host->max_channel = STORVSC_MAX_CHANNELS -1;    /* max # of channels */
 305
 306         /* Register the HBA and start the scsi bus scan */
 307         ret = scsi_add_host(host, device);
 308         if (ret != 0)
 309         {
 310                 DPRINT_ERR(STORVSC_DRV, "unable to add scsi host device");
 311
 312                 storvsc_drv_obj->Base.OnDeviceRemove(device_obj);
 313
 314                 kmem_cache_destroy(host_device_ctx->request_pool);
 315                 scsi_host_put(host);
 316                 DPRINT_EXIT(STORVSC_DRV);
 317
 318                 return -1;
 319         }
 320
 321         scsi_scan_host(host);
 322
 323         DPRINT_EXIT(STORVSC_DRV);
 324
 325         return ret;
 326 }
 327
 328
 329 /*++
 330
 331 Name:   storvsc_remove()
 332
 333 Desc:   Callback when our device is removed
 334
 335 --*/
 336 static int storvsc_remove(struct device *device)
 337 {
 338         int ret=0;
 339
 340         struct driver_context *driver_ctx = driver_to_driver_context(device->driver);
 341         struct storvsc_driver_context *storvsc_drv_ctx = (struct storvsc_driver_context*)driver_ctx;
 342         struct storvsc_driver_object *storvsc_drv_obj = &storvsc_drv_ctx->drv_obj;
 343
 344         struct device_context *device_ctx = device_to_device_context(device);
 345         struct hv_device *device_obj = &device_ctx->device_obj;
 346
 347         struct Scsi_Host *host = dev_get_drvdata(device);
 348         struct host_device_context *host_device_ctx=(struct host_device_context*)host->hostdata;
 349
 350
 351         DPRINT_ENTER(STORVSC_DRV);
 352
 353         if (!storvsc_drv_obj->Base.OnDeviceRemove)
 354         {
 355                 DPRINT_EXIT(STORVSC_DRV);
 356                 return -1;
 357         }
 358
 359         /* Call to the vsc driver to let it know that the device is being removed */
 360         ret = storvsc_drv_obj->Base.OnDeviceRemove(device_obj);
 361         if (ret != 0)
 362         {
 363                 /* TODO: */
 364                 DPRINT_ERR(STORVSC, "unable to remove vsc device (ret %d)", ret);
 365         }
 366
 367         if (host_device_ctx->request_pool)
 368         {
 369                 kmem_cache_destroy(host_device_ctx->request_pool);
 370                 host_device_ctx->request_pool = NULL;
 371         }
 372
 373         DPRINT_INFO(STORVSC, "removing host adapter (%p)...", host);
 374         scsi_remove_host(host);
 375
 376         DPRINT_INFO(STORVSC, "releasing host adapter (%p)...", host);
 377         scsi_host_put(host);
 378
 379         DPRINT_EXIT(STORVSC_DRV);
 380
 381         return ret;
 382 }
 383
 384 /*++
 385
 386 Name:   storvsc_commmand_completion()
 387
 388 Desc:   Command completion processing
 389
 390 --*/
 391 static void storvsc_commmand_completion(struct hv_storvsc_request *request)
 392 {
 393         struct storvsc_cmd_request *cmd_request = (struct storvsc_cmd_request*)request->Context;
 394         struct scsi_cmnd *scmnd = cmd_request->cmd;
 395         struct host_device_context *host_device_ctx = (struct host_device_context*)scmnd->device->host->hostdata;
 396         void (*scsi_done_fn)(struct scsi_cmnd *);
 397         struct scsi_sense_hdr sense_hdr;
 398
 399         ASSERT(request == &cmd_request->request);
 400         ASSERT((unsigned long)scmnd->host_scribble == (unsigned long)cmd_request);
 401         ASSERT(scmnd);
 402         ASSERT(scmnd->scsi_done);
 403
 404         DPRINT_ENTER(STORVSC_DRV);
 405
 406         if (cmd_request->bounce_sgl_count)/* using bounce buffer */
 407         {
 408                 /* printk("copy_from_bounce_buffer\n"); */
 409
 410                 /* FIXME: We can optimize on writes by just skipping this */
 411                 copy_from_bounce_buffer(scsi_sglist(scmnd), cmd_request->bounce_sgl, scsi_sg_count(scmnd));
 412                 destroy_bounce_buffer(cmd_request->bounce_sgl, cmd_request->bounce_sgl_count);
 413         }
 414
 415         scmnd->result = request->Status;
 416
 417         if (scmnd->result)
 418         {
 419                 if (scsi_normalize_sense(scmnd->sense_buffer, request->SenseBufferSize, &sense_hdr))
 420                 {
 421                         scsi_print_sense_hdr("storvsc", &sense_hdr);
 422                 }
 423         }
 424
 425         ASSERT(request->BytesXfer <= request->DataBuffer.Length);
 426         scsi_set_resid(scmnd, request->DataBuffer.Length - request->BytesXfer);
 427
 428         scsi_done_fn = scmnd->scsi_done;
 429
 430         scmnd->host_scribble = NULL;
 431         scmnd->scsi_done = NULL;
 432
 433         /* !!DO NOT MODIFY the scmnd after this call */
 434         scsi_done_fn(scmnd);
 435
 436         kmem_cache_free(host_device_ctx->request_pool, cmd_request);
 437
 438         DPRINT_EXIT(STORVSC_DRV);
 439 }
 440
 441 static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count)
 442 {
 443         int i=0;
 444
 445         /* No need to check */
 446         if (sg_count < 2)
 447                 return -1;
 448
 449         /* We have at least 2 sg entries */
 450         for ( i=0; i<sg_count; i++ )
 451         {
 452                 if (i == 0) /* make sure 1st one does not have hole */
 453                 {
 454                         if (sgl[i].offset + sgl[i].length != PAGE_SIZE)
 455                                 return i;
 456                 }
 457                 else if (i == sg_count - 1) /* make sure last one does not have hole */
 458                 {
 459                         if (sgl[i].offset != 0)
 460                                 return i;
 461                 }
 462                 else /* make sure no hole in the middle */
 463                 {
 464                         if (sgl[i].length != PAGE_SIZE || sgl[i].offset != 0)
 465                         {
 466                                 return i;
 467                         }
 468                 }
 469         }
 470         return -1;
 471 }
 472
 473 static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count, unsigned int len)
 474 {
 475         int i;
 476         int num_pages=0;
 477         struct scatterlist* bounce_sgl;
 478         struct page *page_buf;
 479
 480         num_pages = ALIGN_UP(len, PAGE_SIZE) >> PAGE_SHIFT;
 481
 482         bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC);
 483         if (!bounce_sgl)
 484         {
 485                 return NULL;
 486         }
 487
 488         for(i=0; i<num_pages; i++)
 489         {
 490                 page_buf = alloc_page(GFP_ATOMIC);
 491                 if (!page_buf)
 492                 {
 493                         goto cleanup;
 494                 }
 495                 sg_set_page(&bounce_sgl[i], page_buf, 0, 0);
 496         }
 497
 498         return bounce_sgl;
 499
 500 cleanup:
 501         destroy_bounce_buffer(bounce_sgl, num_pages);
 502         return NULL;
 503 }
 504
 505 static void destroy_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count)
 506 {
 507         int i;
 508         struct page *page_buf;
 509
 510         for (i=0; i<sg_count; i++)
 511         {
 512                 if ((page_buf = sg_page((&sgl[i]))) != NULL)
 513
 514                 {
 515                         __free_page(page_buf);
 516                 }
 517         }
 518
 519         kfree(sgl);
 520 }
 521
 522 /* Assume the bounce_sgl has enough room ie using the create_bounce_buffer() */
 523 static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl, struct scatterlist *bounce_sgl, unsigned int orig_sgl_count)
 524 {
 525         int i=0,j=0;
 526         unsigned long src, dest;
 527         unsigned int srclen, destlen, copylen;
 528         unsigned int total_copied=0;
 529         unsigned long bounce_addr=0;
 530         unsigned long src_addr=0;
 531         unsigned long flags;
 532
 533         local_irq_save(flags);
 534
 535         for (i=0; i<orig_sgl_count; i++)
 536         {
 537                 src_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])), KM_IRQ0) + orig_sgl[i].offset;
 538                 src = src_addr;
 539                 srclen = orig_sgl[i].length;
 540
 541                 /* if (PageHighMem(orig_sgl[i].page)) */
 542                 /* printk("HighMem page detected - addr %p", (void*)src); */
 543
 544                 ASSERT(orig_sgl[i].offset + orig_sgl[i].length <= PAGE_SIZE);
 545
 546                 if (j == 0)
 547                 {
 548                         bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
 549                 }
 550
 551                 while (srclen)
 552                 {
 553                         /* assume bounce offset always == 0 */
 554                         dest = bounce_addr + bounce_sgl[j].length;
 555                         destlen = PAGE_SIZE - bounce_sgl[j].length;
 556
 557                         copylen = min(srclen, destlen);
 558                         memcpy((void*)dest, (void*)src, copylen);
 559
 560                         total_copied += copylen;
 561                         bounce_sgl[j].length += copylen;
 562                         srclen -= copylen;
 563                         src += copylen;
 564
 565                         if (bounce_sgl[j].length == PAGE_SIZE) /* full..move to next entry */
 566                         {
 567                                 kunmap_atomic((void*)bounce_addr, KM_IRQ0);
 568                                 j++;
 569
 570                                 /* if we need to use another bounce buffer */
 571                                 if (srclen || i != orig_sgl_count -1)
 572                                 {
 573                                         bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
 574                                 }
 575                         }
 576                         else if (srclen == 0 && i == orig_sgl_count -1) /* unmap the last bounce that is < PAGE_SIZE */
 577                         {
 578                                 kunmap_atomic((void*)bounce_addr, KM_IRQ0);
 579                         }
 580                 }
 581
 582                 kunmap_atomic((void*)(src_addr - orig_sgl[i].offset), KM_IRQ0);
 583         }
 584
 585         local_irq_restore(flags);
 586
 587         return total_copied;
 588 }
 589
 590 /* Assume the original sgl has enough room */
 591 static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl, struct scatterlist *bounce_sgl, unsigned int orig_sgl_count)
 592 {
 593         int i=0,j=0;
 594         unsigned long src, dest;
 595         unsigned int srclen, destlen, copylen;
 596         unsigned int total_copied=0;
 597         unsigned long bounce_addr=0;
 598         unsigned long dest_addr=0;
 599         unsigned long flags;
 600
 601         local_irq_save(flags);
 602
 603         for (i=0; i<orig_sgl_count; i++)
 604         {
 605                 dest_addr = (unsigned long)kmap_atomic(sg_page((&orig_sgl[i])), KM_IRQ0) + orig_sgl[i].offset;
 606                 dest = dest_addr;
 607                 destlen = orig_sgl[i].length;
 608                 ASSERT(orig_sgl[i].offset + orig_sgl[i].length <= PAGE_SIZE);
 609
 610                 if (j == 0)
 611                 {
 612                         bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
 613                 }
 614
 615                 while (destlen)
 616                 {
 617                         src = bounce_addr + bounce_sgl[j].offset;
 618                         srclen = bounce_sgl[j].length - bounce_sgl[j].offset;
 619
 620                         copylen = min(srclen, destlen);
 621                         memcpy((void*)dest, (void*)src, copylen);
 622
 623                         total_copied += copylen;
 624                         bounce_sgl[j].offset += copylen;
 625                         destlen -= copylen;
 626                         dest += copylen;
 627
 628                         if (bounce_sgl[j].offset == bounce_sgl[j].length) /* full */
 629                         {
 630                                 kunmap_atomic((void*)bounce_addr, KM_IRQ0);
 631                                 j++;
 632
 633                                 /* if we need to use another bounce buffer */
 634                                 if (destlen || i != orig_sgl_count -1)
 635                                 {
 636                                         bounce_addr = (unsigned long)kmap_atomic(sg_page((&bounce_sgl[j])), KM_IRQ0);
 637                                 }
 638                         }
 639                         else if (destlen == 0 && i == orig_sgl_count -1) /* unmap the last bounce that is < PAGE_SIZE */
 640                         {
 641                                 kunmap_atomic((void*)bounce_addr, KM_IRQ0);
 642                         }
 643                 }
 644
 645                 kunmap_atomic((void*)(dest_addr - orig_sgl[i].offset), KM_IRQ0);
 646         }
 647
 648         local_irq_restore(flags);
 649
 650         return total_copied;
 651 }
 652
 653
 654 /*++
 655
 656 Name:   storvsc_queuecommand()
 657
 658 Desc:   Initiate command processing
 659
 660 --*/
 661 static int storvsc_queuecommand(struct scsi_cmnd *scmnd, void (*done)(struct scsi_cmnd *))
 662 {
 663         int ret=0;
 664         struct host_device_context *host_device_ctx = (struct host_device_context*)scmnd->device->host->hostdata;
 665         struct device_context *device_ctx=host_device_ctx->device_ctx;
 666         struct driver_context *driver_ctx = driver_to_driver_context(device_ctx->device.driver);
 667         struct storvsc_driver_context *storvsc_drv_ctx = (struct storvsc_driver_context*)driver_ctx;
 668         struct storvsc_driver_object *storvsc_drv_obj = &storvsc_drv_ctx->drv_obj;
 669
 670         struct hv_storvsc_request *request;
 671         struct storvsc_cmd_request *cmd_request;
 672         unsigned int request_size=0;
 673         int i;
 674         struct scatterlist *sgl;
 675
 676         DPRINT_ENTER(STORVSC_DRV);
 677
 678         DPRINT_DBG(STORVSC_DRV, "scmnd %p dir %d, use_sg %d buf %p len %d queue depth %d tagged %d",
 679                 scmnd,
 680                 scmnd->sc_data_direction,
 681                 scsi_sg_count(scmnd),
 682                 scsi_sglist(scmnd),
 683                 scsi_bufflen(scmnd),
 684                 scmnd->device->queue_depth,
 685                 scmnd->device->tagged_supported);
 686
 687         /* If retrying, no need to prep the cmd */
 688         if (scmnd->host_scribble)
 689         {
 690                 ASSERT(scmnd->scsi_done != NULL);
 691
 692                 cmd_request = (struct storvsc_cmd_request* )scmnd->host_scribble;
 693                 DPRINT_INFO(STORVSC_DRV, "retrying scmnd %p cmd_request %p", scmnd, cmd_request);
 694
 695                 goto retry_request;
 696         }
 697
 698         ASSERT(scmnd->scsi_done == NULL);
 699         ASSERT(scmnd->host_scribble == NULL);
 700
 701         scmnd->scsi_done = done;
 702
 703         request_size = sizeof(struct storvsc_cmd_request);
 704
 705         cmd_request = kmem_cache_alloc(host_device_ctx->request_pool, GFP_ATOMIC);
 706         if (!cmd_request)
 707         {
 708                 DPRINT_ERR(STORVSC_DRV, "scmnd (%p) - unable to allocate storvsc_cmd_request...marking queue busy", scmnd);
 709
 710                 scmnd->scsi_done = NULL;
 711                 return SCSI_MLQUEUE_DEVICE_BUSY;
 712         }
 713
 714         /* Setup the cmd request */
 715         cmd_request->bounce_sgl_count = 0;
 716         cmd_request->bounce_sgl = NULL;
 717         cmd_request->cmd = scmnd;
 718
 719         scmnd->host_scribble = (unsigned char*)cmd_request;
 720
 721         request = &cmd_request->request;
 722
 723         request->Extension = (void*)((unsigned long)cmd_request + request_size);
 724         DPRINT_DBG(STORVSC_DRV, "req %p size %d ext %d", request, request_size, storvsc_drv_obj->RequestExtSize);
 725
 726         /* Build the SRB */
 727         switch(scmnd->sc_data_direction)
 728         {
 729         case DMA_TO_DEVICE:
 730                 request->Type = WRITE_TYPE;
 731                 break;
 732         case DMA_FROM_DEVICE:
 733                 request->Type = READ_TYPE;
 734                 break;
 735         default:
 736                 request->Type = UNKNOWN_TYPE;
 737                 break;
 738         }
 739
 740         request->OnIOCompletion = storvsc_commmand_completion;
 741         request->Context = cmd_request;/* scmnd; */
 742
 743         /* request->PortId = scmnd->device->channel; */
 744         request->Host = host_device_ctx->port;
 745         request->Bus = scmnd->device->channel;
 746         request->TargetId = scmnd->device->id;
 747         request->LunId = scmnd->device->lun;
 748
 749         ASSERT(scmnd->cmd_len <= 16);
 750         request->CdbLen = scmnd->cmd_len;
 751         request->Cdb = scmnd->cmnd;
 752
 753         request->SenseBuffer = scmnd->sense_buffer;
 754         request->SenseBufferSize = SCSI_SENSE_BUFFERSIZE;
 755
 756
 757         request->DataBuffer.Length = scsi_bufflen(scmnd);
 758         if (scsi_sg_count(scmnd))
 759         {
 760                 sgl = (struct scatterlist*)scsi_sglist(scmnd);
 761
 762                 /* check if we need to bounce the sgl */
 763                 if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1)
 764                 {
 765                         DPRINT_INFO(STORVSC_DRV, "need to bounce buffer for this scmnd %p", scmnd);
 766                         cmd_request->bounce_sgl = create_bounce_buffer(sgl, scsi_sg_count(scmnd), scsi_bufflen(scmnd));
 767                         if (!cmd_request->bounce_sgl)
 768                         {
 769                                 DPRINT_ERR(STORVSC_DRV, "unable to create bounce buffer for this scmnd %p", scmnd);
 770
 771                                 scmnd->scsi_done = NULL;
 772                                 scmnd->host_scribble = NULL;
 773                                 kmem_cache_free(host_device_ctx->request_pool, cmd_request);
 774
 775                                 return SCSI_MLQUEUE_HOST_BUSY;
 776                         }
 777
 778                         cmd_request->bounce_sgl_count = ALIGN_UP(scsi_bufflen(scmnd), PAGE_SIZE) >> PAGE_SHIFT;
 779
 780                         /* printk("bouncing buffer allocated %p original buffer %p\n", bounce_sgl, sgl); */
 781                         /* printk("copy_to_bounce_buffer\n"); */
 782                         /* FIXME: We can optimize on reads by just skipping this */
 783                         copy_to_bounce_buffer(sgl, cmd_request->bounce_sgl, scsi_sg_count(scmnd));
 784
 785                         sgl = cmd_request->bounce_sgl;
 786                 }
 787
 788                 request->DataBuffer.Offset = sgl[0].offset;
 789
 790                 for (i = 0; i < scsi_sg_count(scmnd); i++ )
 791                 {
 792                         DPRINT_DBG(STORVSC_DRV, "sgl[%d] len %d offset %d \n", i, sgl[i].length, sgl[i].offset);
 793                         request->DataBuffer.PfnArray[i] = page_to_pfn(sg_page((&sgl[i])));
 794                 }
 795         }
 796
 797         else if (scsi_sglist(scmnd))
 798         {
 799                 ASSERT(scsi_bufflen(scmnd) <= PAGE_SIZE);
 800                 request->DataBuffer.Offset = virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
 801                 request->DataBuffer.PfnArray[0] = virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
 802         }
 803         else
 804         {
 805                 ASSERT(scsi_bufflen(scmnd) == 0);
 806         }
 807
 808 retry_request:
 809
 810         /* Invokes the vsc to start an IO */
 811         ret = storvsc_drv_obj->OnIORequest(&device_ctx->device_obj, &cmd_request->request);
 812         if (ret == -1) /* no more space */
 813         {
 814                 DPRINT_ERR(STORVSC_DRV, "scmnd (%p) - queue FULL...marking queue busy", scmnd);
 815
 816                 if (cmd_request->bounce_sgl_count)
 817                 {
 818                         /* FIXME: We can optimize on writes by just skipping this */
 819                         copy_from_bounce_buffer(scsi_sglist(scmnd), cmd_request->bounce_sgl, scsi_sg_count(scmnd));
 820                         destroy_bounce_buffer(cmd_request->bounce_sgl, cmd_request->bounce_sgl_count);
 821                 }
 822
 823                 kmem_cache_free(host_device_ctx->request_pool, cmd_request);
 824
 825                 scmnd->scsi_done = NULL;
 826                 scmnd->host_scribble = NULL;
 827
 828                 ret = SCSI_MLQUEUE_DEVICE_BUSY;
 829         }
 830
 831         DPRINT_EXIT(STORVSC_DRV);
 832
 833         return ret;
 834 }
 835
 836 static int storvsc_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd, struct bio_vec *bvec)
 837 {
 838         return bvec->bv_len; /* checking done by caller. */
 839 }
 840
 841 /*++
 842
 843 Name:   storvsc_device_configure()
 844
 845 Desc:   Configure the specified scsi device
 846
 847 --*/
 848 static int storvsc_device_alloc(struct scsi_device *sdevice)
 849 {
 850         DPRINT_DBG(STORVSC_DRV, "sdev (%p) - setting device flag to %d", sdevice, BLIST_SPARSELUN);
 851         /* This enables luns to be located sparsely. Otherwise, we may not discovered them. */
 852         sdevice->sdev_bflags |= BLIST_SPARSELUN | BLIST_LARGELUN;
 853         return 0;
 854 }
 855
 856 static int storvsc_device_configure(struct scsi_device *sdevice)
 857 {
 858         DPRINT_INFO(STORVSC_DRV, "sdev (%p) - curr queue depth %d", sdevice, sdevice->queue_depth);
 859
 860         DPRINT_INFO(STORVSC_DRV, "sdev (%p) - setting queue depth to %d", sdevice, STORVSC_MAX_IO_REQUESTS);
 861         scsi_adjust_queue_depth(sdevice, MSG_SIMPLE_TAG, STORVSC_MAX_IO_REQUESTS);
 862
 863         DPRINT_INFO(STORVSC_DRV, "sdev (%p) - setting max segment size to %ld", sdevice, PAGE_SIZE);
 864         blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
 865
 866         DPRINT_INFO(STORVSC_DRV, "sdev (%p) - adding merge bio vec routine", sdevice);
 867         blk_queue_merge_bvec(sdevice->request_queue, storvsc_merge_bvec);
 868
 869         blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
 870         /* sdevice->timeout = (2000 * HZ);//(75 * HZ); */
 871
 872         return 0;
 873 }
 874
 875 /*++
 876
 877 Name:   storvsc_host_reset_handler()
 878
 879 Desc:   Reset the scsi HBA
 880
 881 --*/
 882 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
 883 {
 884         int ret=SUCCESS;
 885         struct host_device_context *host_device_ctx = (struct host_device_context*)scmnd->device->host->hostdata;
 886         struct device_context *device_ctx = host_device_ctx->device_ctx;
 887         struct driver_context *driver_ctx = driver_to_driver_context(device_ctx->device.driver);
 888         struct storvsc_driver_context *storvsc_drv_ctx = (struct storvsc_driver_context*)driver_ctx;
 889
 890         struct storvsc_driver_object *storvsc_drv_obj = &storvsc_drv_ctx->drv_obj;
 891
 892         DPRINT_ENTER(STORVSC_DRV);
 893
 894         DPRINT_INFO(STORVSC_DRV, "sdev (%p) dev obj (%p) - host resetting...", scmnd->device, &device_ctx->device_obj);
 895
 896         /* Invokes the vsc to reset the host/bus */
 897         ASSERT(storvsc_drv_obj->OnHostReset);
 898         ret = storvsc_drv_obj->OnHostReset(&device_ctx->device_obj);
 899         if (ret != 0)
 900         {
 901                 DPRINT_EXIT(STORVSC_DRV);
 902                 return ret;
 903         }
 904
 905         DPRINT_INFO(STORVSC_DRV, "sdev (%p) dev obj (%p) - host reseted", scmnd->device, &device_ctx->device_obj);
 906
 907         DPRINT_EXIT(STORVSC_DRV);
 908
 909         return ret;
 910 }
 911
 912 /*++
 913
 914 Name:   storvsc_host_rescan
 915
 916 Desc:   Rescan the scsi HBA
 917
 918 --*/
 919 static void storvsc_host_rescan_callback(struct work_struct *work)
 920 {
 921         struct hv_device *device_obj =
 922             &((struct host_device_context*)work)->device_ctx->device_obj;
 923         struct device_context* device_ctx = to_device_context(device_obj);
 924         struct Scsi_Host *host = dev_get_drvdata(&device_ctx->device);
 925         struct scsi_device *sdev;
 926         struct host_device_context *host_device_ctx;
 927         struct scsi_device **sdevs_remove_list;
 928         unsigned int sdevs_count=0;
 929         unsigned int found;
 930         unsigned int i;
 931         unsigned int lun_count=0;
 932         unsigned int *lun_list;
 933
 934         DPRINT_ENTER(STORVSC_DRV);
 935
 936         host_device_ctx = (struct host_device_context*)host->hostdata;
 937         lun_list = kcalloc(STORVSC_MAX_LUNS_PER_TARGET, sizeof(unsigned int), GFP_ATOMIC);
 938         if (!lun_list)
 939         {
 940                 DPRINT_ERR(STORVSC_DRV, "unable to allocate lun list");
 941                 return;
 942         }
 943
 944         sdevs_remove_list = kcalloc(STORVSC_MAX_LUNS_PER_TARGET, sizeof(void *), GFP_ATOMIC);
 945         if (!sdevs_remove_list)
 946         {
 947                 kfree(lun_list);
 948                 DPRINT_ERR(STORVSC_DRV, "unable to allocate lun remove list");
 949                 return;
 950         }
 951
 952         DPRINT_INFO(STORVSC_DRV, "rescanning host for new scsi devices...");
 953
 954         /* Rescan for new device */
 955         scsi_scan_target(&host->shost_gendev, host_device_ctx->path, host_device_ctx->target, SCAN_WILD_CARD, 1);
 956
 957         DPRINT_INFO(STORVSC_DRV, "rescanning host for removed scsi device...");
 958
 959         /* Use the 1st device to send the report luns cmd */
 960         shost_for_each_device(sdev, host)
 961         {
 962                 lun_count=STORVSC_MAX_LUNS_PER_TARGET;
 963                 storvsc_report_luns(sdev, lun_list, &lun_count);
 964
 965                 DPRINT_INFO(STORVSC_DRV, "report luns on scsi device (%p) found %u luns ", sdev, lun_count);
 966                 DPRINT_INFO(STORVSC_DRV, "existing luns on scsi device (%p) host (%d)", sdev, host->host_no);
 967
 968                 scsi_device_put(sdev);
 969                 break;
 970         }
 971
 972         for (i=0; i<lun_count; i++)
 973         {
 974                 DPRINT_INFO(STORVSC_DRV, "%d) lun %u", i, lun_list[i]);
 975         }
 976
 977         /* Rescan for devices that may have been removed. */
 978         /* We do not have to worry that new devices may have been added since */
 979         /* this callback is serialized by the workqueue ie add/remove are done here. */
 980         shost_for_each_device(sdev, host)
 981         {
 982                 /* See if this device is still here */
 983                 found = 0;
 984                 for (i=0; i<lun_count; i++)
 985                 {
 986                         if (sdev->lun == lun_list[i])
 987                         {
 988                                 found = 1;
 989                                 break;
 990                         }
 991                 }
 992                 if (!found)
 993                 {
 994                         DPRINT_INFO(STORVSC_DRV, "lun (%u) does not exists", sdev->lun);
 995                         sdevs_remove_list[sdevs_count++] = sdev;
 996                 }
 997         }
 998
 999         /* Now remove the devices */
1000         for (i=0; i< sdevs_count; i++)
1001         {
1002                 DPRINT_INFO(STORVSC_DRV, "removing scsi device (%p) lun (%u)...",
1003                                         sdevs_remove_list[i], sdevs_remove_list[i]->lun);
1004
1005                 /* make sure it is not removed from underneath us */
1006                 if (!scsi_device_get(sdevs_remove_list[i]))
1007                 {
1008                         scsi_remove_device(sdevs_remove_list[i]);
1009                         scsi_device_put(sdevs_remove_list[i]);
1010                 }
1011         }
1012
1013         DPRINT_INFO(STORVSC_DRV, "rescan completed on dev obj (%p) target (%u) bus (%u)", device_obj, host_device_ctx->target, host_device_ctx->path);
1014
1015         kfree(lun_list);
1016         kfree(sdevs_remove_list);
1017
1018         DPRINT_EXIT(STORVSC_DRV);
1019 }
1020
1021 static int storvsc_report_luns(struct scsi_device *sdev, unsigned int luns[], unsigned int *lun_count)
1022 {
1023         int i,j;
1024         unsigned int lun=0;
1025         unsigned int num_luns;
1026         int result;
1027         unsigned char *data;
1028         struct scsi_sense_hdr sshdr;
1029         unsigned char cmd[16]={0};
1030         unsigned int report_len = 8*(STORVSC_MAX_LUNS_PER_TARGET+1); /* Add 1 to cover the report_lun header */
1031         unsigned long long *report_luns;
1032         const unsigned int in_lun_count = *lun_count;
1033
1034         *lun_count = 0;
1035
1036         report_luns = kzalloc(report_len, GFP_ATOMIC);
1037         if (!report_luns)
1038         {
1039                 return -ENOMEM;
1040         }
1041
1042         cmd[0] = REPORT_LUNS;
1043
1044         /* cmd length */
1045         *(unsigned int*)&cmd[6] = cpu_to_be32(report_len);
1046
1047         result = scsi_execute_req(sdev, cmd, DMA_FROM_DEVICE, (unsigned char*)report_luns, report_len, &sshdr, 30*HZ, 3, NULL);
1048         if (result != 0)
1049         {
1050                 kfree(report_luns);
1051                 return -EBUSY;
1052         }
1053
1054         /* get the length from the first four bytes */
1055         report_len = be32_to_cpu(*(unsigned int*)&report_luns[0]);
1056
1057         num_luns = (report_len / sizeof(unsigned long long));
1058         if (num_luns > in_lun_count)
1059         {
1060                 kfree(report_luns);
1061                 return -EINVAL;
1062         }
1063
1064         *lun_count = num_luns;
1065
1066         DPRINT_DBG(STORVSC_DRV, "report luns on scsi device (%p) found %u luns ", sdev, num_luns);
1067
1068         /* lun id starts at 1 */
1069         for (i=1; i< num_luns+1; i++)
1070         {
1071                 lun = 0;
1072                 data = (unsigned char*)&report_luns[i];
1073                 for (j = 0; j < sizeof(lun); j += 2)
1074                  {
1075                          lun = lun | (((data[j] << 8) | data[j + 1]) << (j * 8));
1076                  }
1077
1078                 luns[i-1] = lun;
1079         }
1080
1081         kfree(report_luns);
1082         return 0;
1083 }
1084
1085 static void storvsc_host_rescan(struct hv_device *device_obj)
1086 {
1087         struct device_context* device_ctx = to_device_context(device_obj);
1088         struct Scsi_Host *host = dev_get_drvdata(&device_ctx->device);
1089         struct host_device_context *host_device_ctx;
1090
1091         DPRINT_ENTER(STORVSC_DRV);
1092
1093         host_device_ctx = (struct host_device_context*)host->hostdata;
1094
1095         DPRINT_INFO(STORVSC_DRV, "initiating rescan on dev obj (%p) target (%u) bus (%u)...", device_obj, host_device_ctx->target, host_device_ctx->path);
1096
1097         /* We need to queue this since the scanning may block and the caller may be in an intr context */
1098         /* scsi_queue_work(host, &host_device_ctx->host_rescan_work); */
1099         schedule_work(&host_device_ctx->host_rescan_work);
1100         DPRINT_EXIT(STORVSC_DRV);
1101 }
1102
1103 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev, sector_t capacity, int *info)
1104 {
1105         sector_t total_sectors = capacity;
1106         sector_t cylinder_times_heads=0;
1107         sector_t temp=0;
1108
1109         int sectors_per_track=0;
1110         int heads=0;
1111         int cylinders=0;
1112         int rem=0;
1113
1114     if (total_sectors > (65535 * 16 * 255)) {
1115         total_sectors = (65535 * 16 * 255);
1116     }
1117
1118     if (total_sectors >= (65535 * 16 * 63)) {
1119         sectors_per_track = 255;
1120         heads = 16;
1121
1122                 cylinder_times_heads = total_sectors;
1123                 rem = sector_div(cylinder_times_heads, sectors_per_track); /* sector_div stores the quotient in cylinder_times_heads */
1124     }
1125         else
1126         {
1127         sectors_per_track = 17;
1128
1129                 cylinder_times_heads = total_sectors;
1130         rem = sector_div(cylinder_times_heads, sectors_per_track);      /* sector_div stores the quotient in cylinder_times_heads */
1131
1132                 temp = cylinder_times_heads + 1023;
1133                 rem = sector_div(temp, 1024);   /* sector_div stores the quotient in temp */
1134
1135                 heads = temp;
1136
1137         if (heads < 4) {
1138             heads = 4;
1139         }
1140
1141         if (cylinder_times_heads >= (heads * 1024) || (heads > 16)) {
1142             sectors_per_track = 31;
1143             heads = 16;
1144
1145                         cylinder_times_heads = total_sectors;
1146             rem = sector_div(cylinder_times_heads, sectors_per_track); /* sector_div stores the quotient in cylinder_times_heads */
1147         }
1148
1149         if (cylinder_times_heads >= (heads * 1024)) {
1150             sectors_per_track = 63;
1151             heads = 16;
1152
1153                         cylinder_times_heads = total_sectors;
1154             rem = sector_div(cylinder_times_heads, sectors_per_track); /* sector_div stores the quotient in cylinder_times_heads */
1155         }
1156     }
1157
1158         temp = cylinder_times_heads;
1159     rem = sector_div(temp, heads); /* sector_div stores the quotient in temp */
1160         cylinders = temp;
1161
1162         info[0] = heads;
1163     info[1] = sectors_per_track;
1164     info[2] = cylinders;
1165
1166         DPRINT_INFO(STORVSC_DRV, "CHS (%d, %d, %d)", cylinders, heads, sectors_per_track);
1167
1168     return 0;
1169 }
1170
1171 MODULE_LICENSE("GPL");
1172
1173 static int __init storvsc_init(void)
1174 {
1175         int ret;
1176
1177         DPRINT_ENTER(STORVSC_DRV);
1178
1179         DPRINT_INFO(STORVSC_DRV, "Storvsc initializing....");
1180
1181         ret = storvsc_drv_init(StorVscInitialize);
1182
1183         DPRINT_EXIT(STORVSC_DRV);
1184
1185         return ret;
1186 }
1187
1188 static void __exit storvsc_exit(void)
1189 {
1190         DPRINT_ENTER(STORVSC_DRV);
1191
1192         storvsc_drv_exit();
1193
1194         DPRINT_ENTER(STORVSC_DRV);
1195 }
1196
1197 module_param(storvsc_ringbuffer_size, int, S_IRUGO);
1198
1199 module_init(storvsc_init);
1200 module_exit(storvsc_exit);
1201
1202 /* eof */