drivers/scsi/vmw_pvscsi.c

   1 /*
   2  * Linux driver for VMware's para-virtualized SCSI HBA.
   3  *
   4  * Copyright (C) 2008-2009, VMware, Inc. All Rights Reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the
   8  * Free Software Foundation; version 2 of the License and no later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  13  * NON INFRINGEMENT.  See the GNU General Public License for more
  14  * details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Maintained by: Arvind Kumar <arvindkumar@vmware.com>
  21  *
  22  */
  23
  24 #include <linux/kernel.h>
  25 #include <linux/module.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/slab.h>
  28 #include <linux/workqueue.h>
  29 #include <linux/pci.h>
  30
  31 #include <scsi/scsi.h>
  32 #include <scsi/scsi_host.h>
  33 #include <scsi/scsi_cmnd.h>
  34 #include <scsi/scsi_device.h>
  35
  36 #include "vmw_pvscsi.h"
  37
  38 #define PVSCSI_LINUX_DRIVER_DESC "VMware PVSCSI driver"
  39
  40 MODULE_DESCRIPTION(PVSCSI_LINUX_DRIVER_DESC);
  41 MODULE_AUTHOR("VMware, Inc.");
  42 MODULE_LICENSE("GPL");
  43 MODULE_VERSION(PVSCSI_DRIVER_VERSION_STRING);
  44
  45 #define PVSCSI_DEFAULT_NUM_PAGES_PER_RING       8
  46 #define PVSCSI_DEFAULT_NUM_PAGES_MSG_RING       1
  47 #define PVSCSI_DEFAULT_QUEUE_DEPTH              64
  48 #define SGL_SIZE                                PAGE_SIZE
  49
  50 struct pvscsi_sg_list {
  51         struct PVSCSISGElement sge[PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT];
  52 };
  53
  54 struct pvscsi_ctx {
  55         /*
  56          * The index of the context in cmd_map serves as the context ID for a
  57          * 1-to-1 mapping completions back to requests.
  58          */
  59         struct scsi_cmnd        *cmd;
  60         struct pvscsi_sg_list   *sgl;
  61         struct list_head        list;
  62         dma_addr_t              dataPA;
  63         dma_addr_t              sensePA;
  64         dma_addr_t              sglPA;
  65 };
  66
  67 struct pvscsi_adapter {
  68         char                            *mmioBase;
  69         unsigned int                    irq;
  70         u8                              rev;
  71         bool                            use_msi;
  72         bool                            use_msix;
  73         bool                            use_msg;
  74
  75         spinlock_t                      hw_lock;
  76
  77         struct workqueue_struct         *workqueue;
  78         struct work_struct              work;
  79
  80         struct PVSCSIRingReqDesc        *req_ring;
  81         unsigned                        req_pages;
  82         unsigned                        req_depth;
  83         dma_addr_t                      reqRingPA;
  84
  85         struct PVSCSIRingCmpDesc        *cmp_ring;
  86         unsigned                        cmp_pages;
  87         dma_addr_t                      cmpRingPA;
  88
  89         struct PVSCSIRingMsgDesc        *msg_ring;
  90         unsigned                        msg_pages;
  91         dma_addr_t                      msgRingPA;
  92
  93         struct PVSCSIRingsState         *rings_state;
  94         dma_addr_t                      ringStatePA;
  95
  96         struct pci_dev                  *dev;
  97         struct Scsi_Host                *host;
  98
  99         struct list_head                cmd_pool;
 100         struct pvscsi_ctx               *cmd_map;
 101 };
 102
 103
 104 /* Command line parameters */
 105 static int pvscsi_ring_pages     = PVSCSI_DEFAULT_NUM_PAGES_PER_RING;
 106 static int pvscsi_msg_ring_pages = PVSCSI_DEFAULT_NUM_PAGES_MSG_RING;
 107 static int pvscsi_cmd_per_lun    = PVSCSI_DEFAULT_QUEUE_DEPTH;
 108 static bool pvscsi_disable_msi;
 109 static bool pvscsi_disable_msix;
 110 static bool pvscsi_use_msg       = true;
 111
 112 #define PVSCSI_RW (S_IRUSR | S_IWUSR)
 113
 114 module_param_named(ring_pages, pvscsi_ring_pages, int, PVSCSI_RW);
 115 MODULE_PARM_DESC(ring_pages, "Number of pages per req/cmp ring - (default="
 116                  __stringify(PVSCSI_DEFAULT_NUM_PAGES_PER_RING) ")");
 117
 118 module_param_named(msg_ring_pages, pvscsi_msg_ring_pages, int, PVSCSI_RW);
 119 MODULE_PARM_DESC(msg_ring_pages, "Number of pages for the msg ring - (default="
 120                  __stringify(PVSCSI_DEFAULT_NUM_PAGES_MSG_RING) ")");
 121
 122 module_param_named(cmd_per_lun, pvscsi_cmd_per_lun, int, PVSCSI_RW);
 123 MODULE_PARM_DESC(cmd_per_lun, "Maximum commands per lun - (default="
 124                  __stringify(PVSCSI_MAX_REQ_QUEUE_DEPTH) ")");
 125
 126 module_param_named(disable_msi, pvscsi_disable_msi, bool, PVSCSI_RW);
 127 MODULE_PARM_DESC(disable_msi, "Disable MSI use in driver - (default=0)");
 128
 129 module_param_named(disable_msix, pvscsi_disable_msix, bool, PVSCSI_RW);
 130 MODULE_PARM_DESC(disable_msix, "Disable MSI-X use in driver - (default=0)");
 131
 132 module_param_named(use_msg, pvscsi_use_msg, bool, PVSCSI_RW);
 133 MODULE_PARM_DESC(use_msg, "Use msg ring when available - (default=1)");
 134
 135 static const struct pci_device_id pvscsi_pci_tbl[] = {
 136         { PCI_VDEVICE(VMWARE, PCI_DEVICE_ID_VMWARE_PVSCSI) },
 137         { 0 }
 138 };
 139
 140 MODULE_DEVICE_TABLE(pci, pvscsi_pci_tbl);
 141
 142 static struct device *
 143 pvscsi_dev(const struct pvscsi_adapter *adapter)
 144 {
 145         return &(adapter->dev->dev);
 146 }
 147
 148 static struct pvscsi_ctx *
 149 pvscsi_find_context(const struct pvscsi_adapter *adapter, struct scsi_cmnd *cmd)
 150 {
 151         struct pvscsi_ctx *ctx, *end;
 152
 153         end = &adapter->cmd_map[adapter->req_depth];
 154         for (ctx = adapter->cmd_map; ctx < end; ctx++)
 155                 if (ctx->cmd == cmd)
 156                         return ctx;
 157
 158         return NULL;
 159 }
 160
 161 static struct pvscsi_ctx *
 162 pvscsi_acquire_context(struct pvscsi_adapter *adapter, struct scsi_cmnd *cmd)
 163 {
 164         struct pvscsi_ctx *ctx;
 165
 166         if (list_empty(&adapter->cmd_pool))
 167                 return NULL;
 168
 169         ctx = list_first_entry(&adapter->cmd_pool, struct pvscsi_ctx, list);
 170         ctx->cmd = cmd;
 171         list_del(&ctx->list);
 172
 173         return ctx;
 174 }
 175
 176 static void pvscsi_release_context(struct pvscsi_adapter *adapter,
 177                                    struct pvscsi_ctx *ctx)
 178 {
 179         ctx->cmd = NULL;
 180         list_add(&ctx->list, &adapter->cmd_pool);
 181 }
 182
 183 /*
 184  * Map a pvscsi_ctx struct to a context ID field value; we map to a simple
 185  * non-zero integer. ctx always points to an entry in cmd_map array, hence
 186  * the return value is always >=1.
 187  */
 188 static u64 pvscsi_map_context(const struct pvscsi_adapter *adapter,
 189                               const struct pvscsi_ctx *ctx)
 190 {
 191         return ctx - adapter->cmd_map + 1;
 192 }
 193
 194 static struct pvscsi_ctx *
 195 pvscsi_get_context(const struct pvscsi_adapter *adapter, u64 context)
 196 {
 197         return &adapter->cmd_map[context - 1];
 198 }
 199
 200 static void pvscsi_reg_write(const struct pvscsi_adapter *adapter,
 201                              u32 offset, u32 val)
 202 {
 203         writel(val, adapter->mmioBase + offset);
 204 }
 205
 206 static u32 pvscsi_reg_read(const struct pvscsi_adapter *adapter, u32 offset)
 207 {
 208         return readl(adapter->mmioBase + offset);
 209 }
 210
 211 static u32 pvscsi_read_intr_status(const struct pvscsi_adapter *adapter)
 212 {
 213         return pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_INTR_STATUS);
 214 }
 215
 216 static void pvscsi_write_intr_status(const struct pvscsi_adapter *adapter,
 217                                      u32 val)
 218 {
 219         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_STATUS, val);
 220 }
 221
 222 static void pvscsi_unmask_intr(const struct pvscsi_adapter *adapter)
 223 {
 224         u32 intr_bits;
 225
 226         intr_bits = PVSCSI_INTR_CMPL_MASK;
 227         if (adapter->use_msg)
 228                 intr_bits |= PVSCSI_INTR_MSG_MASK;
 229
 230         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_MASK, intr_bits);
 231 }
 232
 233 static void pvscsi_mask_intr(const struct pvscsi_adapter *adapter)
 234 {
 235         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_MASK, 0);
 236 }
 237
 238 static void pvscsi_write_cmd_desc(const struct pvscsi_adapter *adapter,
 239                                   u32 cmd, const void *desc, size_t len)
 240 {
 241         const u32 *ptr = desc;
 242         size_t i;
 243
 244         len /= sizeof(*ptr);
 245         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND, cmd);
 246         for (i = 0; i < len; i++)
 247                 pvscsi_reg_write(adapter,
 248                                  PVSCSI_REG_OFFSET_COMMAND_DATA, ptr[i]);
 249 }
 250
 251 static void pvscsi_abort_cmd(const struct pvscsi_adapter *adapter,
 252                              const struct pvscsi_ctx *ctx)
 253 {
 254         struct PVSCSICmdDescAbortCmd cmd = { 0 };
 255
 256         cmd.target = ctx->cmd->device->id;
 257         cmd.context = pvscsi_map_context(adapter, ctx);
 258
 259         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_ABORT_CMD, &cmd, sizeof(cmd));
 260 }
 261
 262 static void pvscsi_kick_rw_io(const struct pvscsi_adapter *adapter)
 263 {
 264         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_KICK_RW_IO, 0);
 265 }
 266
 267 static void pvscsi_process_request_ring(const struct pvscsi_adapter *adapter)
 268 {
 269         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_KICK_NON_RW_IO, 0);
 270 }
 271
 272 static int scsi_is_rw(unsigned char op)
 273 {
 274         return op == READ_6  || op == WRITE_6 ||
 275                op == READ_10 || op == WRITE_10 ||
 276                op == READ_12 || op == WRITE_12 ||
 277                op == READ_16 || op == WRITE_16;
 278 }
 279
 280 static void pvscsi_kick_io(const struct pvscsi_adapter *adapter,
 281                            unsigned char op)
 282 {
 283         if (scsi_is_rw(op))
 284                 pvscsi_kick_rw_io(adapter);
 285         else
 286                 pvscsi_process_request_ring(adapter);
 287 }
 288
 289 static void ll_adapter_reset(const struct pvscsi_adapter *adapter)
 290 {
 291         dev_dbg(pvscsi_dev(adapter), "Adapter Reset on %p\n", adapter);
 292
 293         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_ADAPTER_RESET, NULL, 0);
 294 }
 295
 296 static void ll_bus_reset(const struct pvscsi_adapter *adapter)
 297 {
 298         dev_dbg(pvscsi_dev(adapter), "Resetting bus on %p\n", adapter);
 299
 300         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_RESET_BUS, NULL, 0);
 301 }
 302
 303 static void ll_device_reset(const struct pvscsi_adapter *adapter, u32 target)
 304 {
 305         struct PVSCSICmdDescResetDevice cmd = { 0 };
 306
 307         dev_dbg(pvscsi_dev(adapter), "Resetting device: target=%u\n", target);
 308
 309         cmd.target = target;
 310
 311         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_RESET_DEVICE,
 312                               &cmd, sizeof(cmd));
 313 }
 314
 315 static void pvscsi_create_sg(struct pvscsi_ctx *ctx,
 316                              struct scatterlist *sg, unsigned count)
 317 {
 318         unsigned i;
 319         struct PVSCSISGElement *sge;
 320
 321         BUG_ON(count > PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT);
 322
 323         sge = &ctx->sgl->sge[0];
 324         for (i = 0; i < count; i++, sg++) {
 325                 sge[i].addr   = sg_dma_address(sg);
 326                 sge[i].length = sg_dma_len(sg);
 327                 sge[i].flags  = 0;
 328         }
 329 }
 330
 331 /*
 332  * Map all data buffers for a command into PCI space and
 333  * setup the scatter/gather list if needed.
 334  */
 335 static void pvscsi_map_buffers(struct pvscsi_adapter *adapter,
 336                                struct pvscsi_ctx *ctx, struct scsi_cmnd *cmd,
 337                                struct PVSCSIRingReqDesc *e)
 338 {
 339         unsigned count;
 340         unsigned bufflen = scsi_bufflen(cmd);
 341         struct scatterlist *sg;
 342
 343         e->dataLen = bufflen;
 344         e->dataAddr = 0;
 345         if (bufflen == 0)
 346                 return;
 347
 348         sg = scsi_sglist(cmd);
 349         count = scsi_sg_count(cmd);
 350         if (count != 0) {
 351                 int segs = scsi_dma_map(cmd);
 352                 if (segs > 1) {
 353                         pvscsi_create_sg(ctx, sg, segs);
 354
 355                         e->flags |= PVSCSI_FLAG_CMD_WITH_SG_LIST;
 356                         ctx->sglPA = pci_map_single(adapter->dev, ctx->sgl,
 357                                                     SGL_SIZE, PCI_DMA_TODEVICE);
 358                         e->dataAddr = ctx->sglPA;
 359                 } else
 360                         e->dataAddr = sg_dma_address(sg);
 361         } else {
 362                 /*
 363                  * In case there is no S/G list, scsi_sglist points
 364                  * directly to the buffer.
 365                  */
 366                 ctx->dataPA = pci_map_single(adapter->dev, sg, bufflen,
 367                                              cmd->sc_data_direction);
 368                 e->dataAddr = ctx->dataPA;
 369         }
 370 }
 371
 372 static void pvscsi_unmap_buffers(const struct pvscsi_adapter *adapter,
 373                                  struct pvscsi_ctx *ctx)
 374 {
 375         struct scsi_cmnd *cmd;
 376         unsigned bufflen;
 377
 378         cmd = ctx->cmd;
 379         bufflen = scsi_bufflen(cmd);
 380
 381         if (bufflen != 0) {
 382                 unsigned count = scsi_sg_count(cmd);
 383
 384                 if (count != 0) {
 385                         scsi_dma_unmap(cmd);
 386                         if (ctx->sglPA) {
 387                                 pci_unmap_single(adapter->dev, ctx->sglPA,
 388                                                  SGL_SIZE, PCI_DMA_TODEVICE);
 389                                 ctx->sglPA = 0;
 390                         }
 391                 } else
 392                         pci_unmap_single(adapter->dev, ctx->dataPA, bufflen,
 393                                          cmd->sc_data_direction);
 394         }
 395         if (cmd->sense_buffer)
 396                 pci_unmap_single(adapter->dev, ctx->sensePA,
 397                                  SCSI_SENSE_BUFFERSIZE, PCI_DMA_FROMDEVICE);
 398 }
 399
 400 static int __devinit pvscsi_allocate_rings(struct pvscsi_adapter *adapter)
 401 {
 402         adapter->rings_state = pci_alloc_consistent(adapter->dev, PAGE_SIZE,
 403                                                     &adapter->ringStatePA);
 404         if (!adapter->rings_state)
 405                 return -ENOMEM;
 406
 407         adapter->req_pages = min(PVSCSI_MAX_NUM_PAGES_REQ_RING,
 408                                  pvscsi_ring_pages);
 409         adapter->req_depth = adapter->req_pages
 410                                         * PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
 411         adapter->req_ring = pci_alloc_consistent(adapter->dev,
 412                                                  adapter->req_pages * PAGE_SIZE,
 413                                                  &adapter->reqRingPA);
 414         if (!adapter->req_ring)
 415                 return -ENOMEM;
 416
 417         adapter->cmp_pages = min(PVSCSI_MAX_NUM_PAGES_CMP_RING,
 418                                  pvscsi_ring_pages);
 419         adapter->cmp_ring = pci_alloc_consistent(adapter->dev,
 420                                                  adapter->cmp_pages * PAGE_SIZE,
 421                                                  &adapter->cmpRingPA);
 422         if (!adapter->cmp_ring)
 423                 return -ENOMEM;
 424
 425         BUG_ON(!IS_ALIGNED(adapter->ringStatePA, PAGE_SIZE));
 426         BUG_ON(!IS_ALIGNED(adapter->reqRingPA, PAGE_SIZE));
 427         BUG_ON(!IS_ALIGNED(adapter->cmpRingPA, PAGE_SIZE));
 428
 429         if (!adapter->use_msg)
 430                 return 0;
 431
 432         adapter->msg_pages = min(PVSCSI_MAX_NUM_PAGES_MSG_RING,
 433                                  pvscsi_msg_ring_pages);
 434         adapter->msg_ring = pci_alloc_consistent(adapter->dev,
 435                                                  adapter->msg_pages * PAGE_SIZE,
 436                                                  &adapter->msgRingPA);
 437         if (!adapter->msg_ring)
 438                 return -ENOMEM;
 439         BUG_ON(!IS_ALIGNED(adapter->msgRingPA, PAGE_SIZE));
 440
 441         return 0;
 442 }
 443
 444 static void pvscsi_setup_all_rings(const struct pvscsi_adapter *adapter)
 445 {
 446         struct PVSCSICmdDescSetupRings cmd = { 0 };
 447         dma_addr_t base;
 448         unsigned i;
 449
 450         cmd.ringsStatePPN   = adapter->ringStatePA >> PAGE_SHIFT;
 451         cmd.reqRingNumPages = adapter->req_pages;
 452         cmd.cmpRingNumPages = adapter->cmp_pages;
 453
 454         base = adapter->reqRingPA;
 455         for (i = 0; i < adapter->req_pages; i++) {
 456                 cmd.reqRingPPNs[i] = base >> PAGE_SHIFT;
 457                 base += PAGE_SIZE;
 458         }
 459
 460         base = adapter->cmpRingPA;
 461         for (i = 0; i < adapter->cmp_pages; i++) {
 462                 cmd.cmpRingPPNs[i] = base >> PAGE_SHIFT;
 463                 base += PAGE_SIZE;
 464         }
 465
 466         memset(adapter->rings_state, 0, PAGE_SIZE);
 467         memset(adapter->req_ring, 0, adapter->req_pages * PAGE_SIZE);
 468         memset(adapter->cmp_ring, 0, adapter->cmp_pages * PAGE_SIZE);
 469
 470         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_RINGS,
 471                               &cmd, sizeof(cmd));
 472
 473         if (adapter->use_msg) {
 474                 struct PVSCSICmdDescSetupMsgRing cmd_msg = { 0 };
 475
 476                 cmd_msg.numPages = adapter->msg_pages;
 477
 478                 base = adapter->msgRingPA;
 479                 for (i = 0; i < adapter->msg_pages; i++) {
 480                         cmd_msg.ringPPNs[i] = base >> PAGE_SHIFT;
 481                         base += PAGE_SIZE;
 482                 }
 483                 memset(adapter->msg_ring, 0, adapter->msg_pages * PAGE_SIZE);
 484
 485                 pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_MSG_RING,
 486                                       &cmd_msg, sizeof(cmd_msg));
 487         }
 488 }
 489
 490 /*
 491  * Pull a completion descriptor off and pass the completion back
 492  * to the SCSI mid layer.
 493  */
 494 static void pvscsi_complete_request(struct pvscsi_adapter *adapter,
 495                                     const struct PVSCSIRingCmpDesc *e)
 496 {
 497         struct pvscsi_ctx *ctx;
 498         struct scsi_cmnd *cmd;
 499         u32 btstat = e->hostStatus;
 500         u32 sdstat = e->scsiStatus;
 501
 502         ctx = pvscsi_get_context(adapter, e->context);
 503         cmd = ctx->cmd;
 504         pvscsi_unmap_buffers(adapter, ctx);
 505         pvscsi_release_context(adapter, ctx);
 506         cmd->result = 0;
 507
 508         if (sdstat != SAM_STAT_GOOD &&
 509             (btstat == BTSTAT_SUCCESS ||
 510              btstat == BTSTAT_LINKED_COMMAND_COMPLETED ||
 511              btstat == BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG)) {
 512                 cmd->result = (DID_OK << 16) | sdstat;
 513                 if (sdstat == SAM_STAT_CHECK_CONDITION && cmd->sense_buffer)
 514                         cmd->result |= (DRIVER_SENSE << 24);
 515         } else
 516                 switch (btstat) {
 517                 case BTSTAT_SUCCESS:
 518                 case BTSTAT_LINKED_COMMAND_COMPLETED:
 519                 case BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG:
 520                         /* If everything went fine, let's move on..  */
 521                         cmd->result = (DID_OK << 16);
 522                         break;
 523
 524                 case BTSTAT_DATARUN:
 525                 case BTSTAT_DATA_UNDERRUN:
 526                         /* Report residual data in underruns */
 527                         scsi_set_resid(cmd, scsi_bufflen(cmd) - e->dataLen);
 528                         cmd->result = (DID_ERROR << 16);
 529                         break;
 530
 531                 case BTSTAT_SELTIMEO:
 532                         /* Our emulation returns this for non-connected devs */
 533                         cmd->result = (DID_BAD_TARGET << 16);
 534                         break;
 535
 536                 case BTSTAT_LUNMISMATCH:
 537                 case BTSTAT_TAGREJECT:
 538                 case BTSTAT_BADMSG:
 539                         cmd->result = (DRIVER_INVALID << 24);
 540                         /* fall through */
 541
 542                 case BTSTAT_HAHARDWARE:
 543                 case BTSTAT_INVPHASE:
 544                 case BTSTAT_HATIMEOUT:
 545                 case BTSTAT_NORESPONSE:
 546                 case BTSTAT_DISCONNECT:
 547                 case BTSTAT_HASOFTWARE:
 548                 case BTSTAT_BUSFREE:
 549                 case BTSTAT_SENSFAILED:
 550                         cmd->result |= (DID_ERROR << 16);
 551                         break;
 552
 553                 case BTSTAT_SENTRST:
 554                 case BTSTAT_RECVRST:
 555                 case BTSTAT_BUSRESET:
 556                         cmd->result = (DID_RESET << 16);
 557                         break;
 558
 559                 case BTSTAT_ABORTQUEUE:
 560                         cmd->result = (DID_ABORT << 16);
 561                         break;
 562
 563                 case BTSTAT_SCSIPARITY:
 564                         cmd->result = (DID_PARITY << 16);
 565                         break;
 566
 567                 default:
 568                         cmd->result = (DID_ERROR << 16);
 569                         scmd_printk(KERN_DEBUG, cmd,
 570                                     "Unknown completion status: 0x%x\n",
 571                                     btstat);
 572         }
 573
 574         dev_dbg(&cmd->device->sdev_gendev,
 575                 "cmd=%p %x ctx=%p result=0x%x status=0x%x,%x\n",
 576                 cmd, cmd->cmnd[0], ctx, cmd->result, btstat, sdstat);
 577
 578         cmd->scsi_done(cmd);
 579 }
 580
 581 /*
 582  * barrier usage : Since the PVSCSI device is emulated, there could be cases
 583  * where we may want to serialize some accesses between the driver and the
 584  * emulation layer. We use compiler barriers instead of the more expensive
 585  * memory barriers because PVSCSI is only supported on X86 which has strong
 586  * memory access ordering.
 587  */
 588 static void pvscsi_process_completion_ring(struct pvscsi_adapter *adapter)
 589 {
 590         struct PVSCSIRingsState *s = adapter->rings_state;
 591         struct PVSCSIRingCmpDesc *ring = adapter->cmp_ring;
 592         u32 cmp_entries = s->cmpNumEntriesLog2;
 593
 594         while (s->cmpConsIdx != s->cmpProdIdx) {
 595                 struct PVSCSIRingCmpDesc *e = ring + (s->cmpConsIdx &
 596                                                       MASK(cmp_entries));
 597                 /*
 598                  * This barrier() ensures that *e is not dereferenced while
 599                  * the device emulation still writes data into the slot.
 600                  * Since the device emulation advances s->cmpProdIdx only after
 601                  * updating the slot we want to check it first.
 602                  */
 603                 barrier();
 604                 pvscsi_complete_request(adapter, e);
 605                 /*
 606                  * This barrier() ensures that compiler doesn't reorder write
 607                  * to s->cmpConsIdx before the read of (*e) inside
 608                  * pvscsi_complete_request. Otherwise, device emulation may
 609                  * overwrite *e before we had a chance to read it.
 610                  */
 611                 barrier();
 612                 s->cmpConsIdx++;
 613         }
 614 }
 615
 616 /*
 617  * Translate a Linux SCSI request into a request ring entry.
 618  */
 619 static int pvscsi_queue_ring(struct pvscsi_adapter *adapter,
 620                              struct pvscsi_ctx *ctx, struct scsi_cmnd *cmd)
 621 {
 622         struct PVSCSIRingsState *s;
 623         struct PVSCSIRingReqDesc *e;
 624         struct scsi_device *sdev;
 625         u32 req_entries;
 626
 627         s = adapter->rings_state;
 628         sdev = cmd->device;
 629         req_entries = s->reqNumEntriesLog2;
 630
 631         /*
 632          * If this condition holds, we might have room on the request ring, but
 633          * we might not have room on the completion ring for the response.
 634          * However, we have already ruled out this possibility - we would not
 635          * have successfully allocated a context if it were true, since we only
 636          * have one context per request entry.  Check for it anyway, since it
 637          * would be a serious bug.
 638          */
 639         if (s->reqProdIdx - s->cmpConsIdx >= 1 << req_entries) {
 640                 scmd_printk(KERN_ERR, cmd, "vmw_pvscsi: "
 641                             "ring full: reqProdIdx=%d cmpConsIdx=%d\n",
 642                             s->reqProdIdx, s->cmpConsIdx);
 643                 return -1;
 644         }
 645
 646         e = adapter->req_ring + (s->reqProdIdx & MASK(req_entries));
 647
 648         e->bus    = sdev->channel;
 649         e->target = sdev->id;
 650         memset(e->lun, 0, sizeof(e->lun));
 651         e->lun[1] = sdev->lun;
 652
 653         if (cmd->sense_buffer) {
 654                 ctx->sensePA = pci_map_single(adapter->dev, cmd->sense_buffer,
 655                                               SCSI_SENSE_BUFFERSIZE,
 656                                               PCI_DMA_FROMDEVICE);
 657                 e->senseAddr = ctx->sensePA;
 658                 e->senseLen = SCSI_SENSE_BUFFERSIZE;
 659         } else {
 660                 e->senseLen  = 0;
 661                 e->senseAddr = 0;
 662         }
 663         e->cdbLen   = cmd->cmd_len;
 664         e->vcpuHint = smp_processor_id();
 665         memcpy(e->cdb, cmd->cmnd, e->cdbLen);
 666
 667         e->tag = SIMPLE_QUEUE_TAG;
 668         if (sdev->tagged_supported &&
 669             (cmd->tag == HEAD_OF_QUEUE_TAG ||
 670              cmd->tag == ORDERED_QUEUE_TAG))
 671                 e->tag = cmd->tag;
 672
 673         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
 674                 e->flags = PVSCSI_FLAG_CMD_DIR_TOHOST;
 675         else if (cmd->sc_data_direction == DMA_TO_DEVICE)
 676                 e->flags = PVSCSI_FLAG_CMD_DIR_TODEVICE;
 677         else if (cmd->sc_data_direction == DMA_NONE)
 678                 e->flags = PVSCSI_FLAG_CMD_DIR_NONE;
 679         else
 680                 e->flags = 0;
 681
 682         pvscsi_map_buffers(adapter, ctx, cmd, e);
 683
 684         e->context = pvscsi_map_context(adapter, ctx);
 685
 686         barrier();
 687
 688         s->reqProdIdx++;
 689
 690         return 0;
 691 }
 692
 693 static int pvscsi_queue_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
 694 {
 695         struct Scsi_Host *host = cmd->device->host;
 696         struct pvscsi_adapter *adapter = shost_priv(host);
 697         struct pvscsi_ctx *ctx;
 698         unsigned long flags;
 699
 700         spin_lock_irqsave(&adapter->hw_lock, flags);
 701
 702         ctx = pvscsi_acquire_context(adapter, cmd);
 703         if (!ctx || pvscsi_queue_ring(adapter, ctx, cmd) != 0) {
 704                 if (ctx)
 705                         pvscsi_release_context(adapter, ctx);
 706                 spin_unlock_irqrestore(&adapter->hw_lock, flags);
 707                 return SCSI_MLQUEUE_HOST_BUSY;
 708         }
 709
 710         cmd->scsi_done = done;
 711
 712         dev_dbg(&cmd->device->sdev_gendev,
 713                 "queued cmd %p, ctx %p, op=%x\n", cmd, ctx, cmd->cmnd[0]);
 714
 715         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 716
 717         pvscsi_kick_io(adapter, cmd->cmnd[0]);
 718
 719         return 0;
 720 }
 721
 722 static DEF_SCSI_QCMD(pvscsi_queue)
 723
 724 static int pvscsi_abort(struct scsi_cmnd *cmd)
 725 {
 726         struct pvscsi_adapter *adapter = shost_priv(cmd->device->host);
 727         struct pvscsi_ctx *ctx;
 728         unsigned long flags;
 729
 730         scmd_printk(KERN_DEBUG, cmd, "task abort on host %u, %p\n",
 731                     adapter->host->host_no, cmd);
 732
 733         spin_lock_irqsave(&adapter->hw_lock, flags);
 734
 735         /*
 736          * Poll the completion ring first - we might be trying to abort
 737          * a command that is waiting to be dispatched in the completion ring.
 738          */
 739         pvscsi_process_completion_ring(adapter);
 740
 741         /*
 742          * If there is no context for the command, it either already succeeded
 743          * or else was never properly issued.  Not our problem.
 744          */
 745         ctx = pvscsi_find_context(adapter, cmd);
 746         if (!ctx) {
 747                 scmd_printk(KERN_DEBUG, cmd, "Failed to abort cmd %p\n", cmd);
 748                 goto out;
 749         }
 750
 751         pvscsi_abort_cmd(adapter, ctx);
 752
 753         pvscsi_process_completion_ring(adapter);
 754
 755 out:
 756         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 757         return SUCCESS;
 758 }
 759
 760 /*
 761  * Abort all outstanding requests.  This is only safe to use if the completion
 762  * ring will never be walked again or the device has been reset, because it
 763  * destroys the 1-1 mapping between context field passed to emulation and our
 764  * request structure.
 765  */
 766 static void pvscsi_reset_all(struct pvscsi_adapter *adapter)
 767 {
 768         unsigned i;
 769
 770         for (i = 0; i < adapter->req_depth; i++) {
 771                 struct pvscsi_ctx *ctx = &adapter->cmd_map[i];
 772                 struct scsi_cmnd *cmd = ctx->cmd;
 773                 if (cmd) {
 774                         scmd_printk(KERN_ERR, cmd,
 775                                     "Forced reset on cmd %p\n", cmd);
 776                         pvscsi_unmap_buffers(adapter, ctx);
 777                         pvscsi_release_context(adapter, ctx);
 778                         cmd->result = (DID_RESET << 16);
 779                         cmd->scsi_done(cmd);
 780                 }
 781         }
 782 }
 783
 784 static int pvscsi_host_reset(struct scsi_cmnd *cmd)
 785 {
 786         struct Scsi_Host *host = cmd->device->host;
 787         struct pvscsi_adapter *adapter = shost_priv(host);
 788         unsigned long flags;
 789         bool use_msg;
 790
 791         scmd_printk(KERN_INFO, cmd, "SCSI Host reset\n");
 792
 793         spin_lock_irqsave(&adapter->hw_lock, flags);
 794
 795         use_msg = adapter->use_msg;
 796
 797         if (use_msg) {
 798                 adapter->use_msg = 0;
 799                 spin_unlock_irqrestore(&adapter->hw_lock, flags);
 800
 801                 /*
 802                  * Now that we know that the ISR won't add more work on the
 803                  * workqueue we can safely flush any outstanding work.
 804                  */
 805                 flush_workqueue(adapter->workqueue);
 806                 spin_lock_irqsave(&adapter->hw_lock, flags);
 807         }
 808
 809         /*
 810          * We're going to tear down the entire ring structure and set it back
 811          * up, so stalling new requests until all completions are flushed and
 812          * the rings are back in place.
 813          */
 814
 815         pvscsi_process_request_ring(adapter);
 816
 817         ll_adapter_reset(adapter);
 818
 819         /*
 820          * Now process any completions.  Note we do this AFTER adapter reset,
 821          * which is strange, but stops races where completions get posted
 822          * between processing the ring and issuing the reset.  The backend will
 823          * not touch the ring memory after reset, so the immediately pre-reset
 824          * completion ring state is still valid.
 825          */
 826         pvscsi_process_completion_ring(adapter);
 827
 828         pvscsi_reset_all(adapter);
 829         adapter->use_msg = use_msg;
 830         pvscsi_setup_all_rings(adapter);
 831         pvscsi_unmask_intr(adapter);
 832
 833         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 834
 835         return SUCCESS;
 836 }
 837
 838 static int pvscsi_bus_reset(struct scsi_cmnd *cmd)
 839 {
 840         struct Scsi_Host *host = cmd->device->host;
 841         struct pvscsi_adapter *adapter = shost_priv(host);
 842         unsigned long flags;
 843
 844         scmd_printk(KERN_INFO, cmd, "SCSI Bus reset\n");
 845
 846         /*
 847          * We don't want to queue new requests for this bus after
 848          * flushing all pending requests to emulation, since new
 849          * requests could then sneak in during this bus reset phase,
 850          * so take the lock now.
 851          */
 852         spin_lock_irqsave(&adapter->hw_lock, flags);
 853
 854         pvscsi_process_request_ring(adapter);
 855         ll_bus_reset(adapter);
 856         pvscsi_process_completion_ring(adapter);
 857
 858         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 859
 860         return SUCCESS;
 861 }
 862
 863 static int pvscsi_device_reset(struct scsi_cmnd *cmd)
 864 {
 865         struct Scsi_Host *host = cmd->device->host;
 866         struct pvscsi_adapter *adapter = shost_priv(host);
 867         unsigned long flags;
 868
 869         scmd_printk(KERN_INFO, cmd, "SCSI device reset on scsi%u:%u\n",
 870                     host->host_no, cmd->device->id);
 871
 872         /*
 873          * We don't want to queue new requests for this device after flushing
 874          * all pending requests to emulation, since new requests could then
 875          * sneak in during this device reset phase, so take the lock now.
 876          */
 877         spin_lock_irqsave(&adapter->hw_lock, flags);
 878
 879         pvscsi_process_request_ring(adapter);
 880         ll_device_reset(adapter, cmd->device->id);
 881         pvscsi_process_completion_ring(adapter);
 882
 883         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 884
 885         return SUCCESS;
 886 }
 887
 888 static struct scsi_host_template pvscsi_template;
 889
 890 static const char *pvscsi_info(struct Scsi_Host *host)
 891 {
 892         struct pvscsi_adapter *adapter = shost_priv(host);
 893         static char buf[256];
 894
 895         sprintf(buf, "VMware PVSCSI storage adapter rev %d, req/cmp/msg rings: "
 896                 "%u/%u/%u pages, cmd_per_lun=%u", adapter->rev,
 897                 adapter->req_pages, adapter->cmp_pages, adapter->msg_pages,
 898                 pvscsi_template.cmd_per_lun);
 899
 900         return buf;
 901 }
 902
 903 static struct scsi_host_template pvscsi_template = {
 904         .module                         = THIS_MODULE,
 905         .name                           = "VMware PVSCSI Host Adapter",
 906         .proc_name                      = "vmw_pvscsi",
 907         .info                           = pvscsi_info,
 908         .queuecommand                   = pvscsi_queue,
 909         .this_id                        = -1,
 910         .sg_tablesize                   = PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT,
 911         .dma_boundary                   = UINT_MAX,
 912         .max_sectors                    = 0xffff,
 913         .use_clustering                 = ENABLE_CLUSTERING,
 914         .eh_abort_handler               = pvscsi_abort,
 915         .eh_device_reset_handler        = pvscsi_device_reset,
 916         .eh_bus_reset_handler           = pvscsi_bus_reset,
 917         .eh_host_reset_handler          = pvscsi_host_reset,
 918 };
 919
 920 static void pvscsi_process_msg(const struct pvscsi_adapter *adapter,
 921                                const struct PVSCSIRingMsgDesc *e)
 922 {
 923         struct PVSCSIRingsState *s = adapter->rings_state;
 924         struct Scsi_Host *host = adapter->host;
 925         struct scsi_device *sdev;
 926
 927         printk(KERN_INFO "vmw_pvscsi: msg type: 0x%x - MSG RING: %u/%u (%u) \n",
 928                e->type, s->msgProdIdx, s->msgConsIdx, s->msgNumEntriesLog2);
 929
 930         BUILD_BUG_ON(PVSCSI_MSG_LAST != 2);
 931
 932         if (e->type == PVSCSI_MSG_DEV_ADDED) {
 933                 struct PVSCSIMsgDescDevStatusChanged *desc;
 934                 desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
 935
 936                 printk(KERN_INFO
 937                        "vmw_pvscsi: msg: device added at scsi%u:%u:%u\n",
 938                        desc->bus, desc->target, desc->lun[1]);
 939
 940                 if (!scsi_host_get(host))
 941                         return;
 942
 943                 sdev = scsi_device_lookup(host, desc->bus, desc->target,
 944                                           desc->lun[1]);
 945                 if (sdev) {
 946                         printk(KERN_INFO "vmw_pvscsi: device already exists\n");
 947                         scsi_device_put(sdev);
 948                 } else
 949                         scsi_add_device(adapter->host, desc->bus,
 950                                         desc->target, desc->lun[1]);
 951
 952                 scsi_host_put(host);
 953         } else if (e->type == PVSCSI_MSG_DEV_REMOVED) {
 954                 struct PVSCSIMsgDescDevStatusChanged *desc;
 955                 desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
 956
 957                 printk(KERN_INFO
 958                        "vmw_pvscsi: msg: device removed at scsi%u:%u:%u\n",
 959                        desc->bus, desc->target, desc->lun[1]);
 960
 961                 if (!scsi_host_get(host))
 962                         return;
 963
 964                 sdev = scsi_device_lookup(host, desc->bus, desc->target,
 965                                           desc->lun[1]);
 966                 if (sdev) {
 967                         scsi_remove_device(sdev);
 968                         scsi_device_put(sdev);
 969                 } else
 970                         printk(KERN_INFO
 971                                "vmw_pvscsi: failed to lookup scsi%u:%u:%u\n",
 972                                desc->bus, desc->target, desc->lun[1]);
 973
 974                 scsi_host_put(host);
 975         }
 976 }
 977
 978 static int pvscsi_msg_pending(const struct pvscsi_adapter *adapter)
 979 {
 980         struct PVSCSIRingsState *s = adapter->rings_state;
 981
 982         return s->msgProdIdx != s->msgConsIdx;
 983 }
 984
 985 static void pvscsi_process_msg_ring(const struct pvscsi_adapter *adapter)
 986 {
 987         struct PVSCSIRingsState *s = adapter->rings_state;
 988         struct PVSCSIRingMsgDesc *ring = adapter->msg_ring;
 989         u32 msg_entries = s->msgNumEntriesLog2;
 990
 991         while (pvscsi_msg_pending(adapter)) {
 992                 struct PVSCSIRingMsgDesc *e = ring + (s->msgConsIdx &
 993                                                       MASK(msg_entries));
 994
 995                 barrier();
 996                 pvscsi_process_msg(adapter, e);
 997                 barrier();
 998                 s->msgConsIdx++;
 999         }
1000 }
1001
1002 static void pvscsi_msg_workqueue_handler(struct work_struct *data)
1003 {
1004         struct pvscsi_adapter *adapter;
1005
1006         adapter = container_of(data, struct pvscsi_adapter, work);
1007
1008         pvscsi_process_msg_ring(adapter);
1009 }
1010
1011 static int pvscsi_setup_msg_workqueue(struct pvscsi_adapter *adapter)
1012 {
1013         char name[32];
1014
1015         if (!pvscsi_use_msg)
1016                 return 0;
1017
1018         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND,
1019                          PVSCSI_CMD_SETUP_MSG_RING);
1020
1021         if (pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS) == -1)
1022                 return 0;
1023
1024         snprintf(name, sizeof(name),
1025                  "vmw_pvscsi_wq_%u", adapter->host->host_no);
1026
1027         adapter->workqueue = create_singlethread_workqueue(name);
1028         if (!adapter->workqueue) {
1029                 printk(KERN_ERR "vmw_pvscsi: failed to create work queue\n");
1030                 return 0;
1031         }
1032         INIT_WORK(&adapter->work, pvscsi_msg_workqueue_handler);
1033
1034         return 1;
1035 }
1036
1037 static irqreturn_t pvscsi_isr(int irq, void *devp)
1038 {
1039         struct pvscsi_adapter *adapter = devp;
1040         int handled;
1041
1042         if (adapter->use_msi || adapter->use_msix)
1043                 handled = true;
1044         else {
1045                 u32 val = pvscsi_read_intr_status(adapter);
1046                 handled = (val & PVSCSI_INTR_ALL_SUPPORTED) != 0;
1047                 if (handled)
1048                         pvscsi_write_intr_status(devp, val);
1049         }
1050
1051         if (handled) {
1052                 unsigned long flags;
1053
1054                 spin_lock_irqsave(&adapter->hw_lock, flags);
1055
1056                 pvscsi_process_completion_ring(adapter);
1057                 if (adapter->use_msg && pvscsi_msg_pending(adapter))
1058                         queue_work(adapter->workqueue, &adapter->work);
1059
1060                 spin_unlock_irqrestore(&adapter->hw_lock, flags);
1061         }
1062
1063         return IRQ_RETVAL(handled);
1064 }
1065
1066 static void pvscsi_free_sgls(const struct pvscsi_adapter *adapter)
1067 {
1068         struct pvscsi_ctx *ctx = adapter->cmd_map;
1069         unsigned i;
1070
1071         for (i = 0; i < adapter->req_depth; ++i, ++ctx)
1072                 free_pages((unsigned long)ctx->sgl, get_order(SGL_SIZE));
1073 }
1074
1075 static int pvscsi_setup_msix(const struct pvscsi_adapter *adapter,
1076                              unsigned int *irq)
1077 {
1078         struct msix_entry entry = { 0, PVSCSI_VECTOR_COMPLETION };
1079         int ret;
1080
1081         ret = pci_enable_msix(adapter->dev, &entry, 1);
1082         if (ret)
1083                 return ret;
1084
1085         *irq = entry.vector;
1086
1087         return 0;
1088 }
1089
1090 static void pvscsi_shutdown_intr(struct pvscsi_adapter *adapter)
1091 {
1092         if (adapter->irq) {
1093                 free_irq(adapter->irq, adapter);
1094                 adapter->irq = 0;
1095         }
1096         if (adapter->use_msi) {
1097                 pci_disable_msi(adapter->dev);
1098                 adapter->use_msi = 0;
1099         } else if (adapter->use_msix) {
1100                 pci_disable_msix(adapter->dev);
1101                 adapter->use_msix = 0;
1102         }
1103 }
1104
1105 static void pvscsi_release_resources(struct pvscsi_adapter *adapter)
1106 {
1107         pvscsi_shutdown_intr(adapter);
1108
1109         if (adapter->workqueue)
1110                 destroy_workqueue(adapter->workqueue);
1111
1112         if (adapter->mmioBase)
1113                 pci_iounmap(adapter->dev, adapter->mmioBase);
1114
1115         pci_release_regions(adapter->dev);
1116
1117         if (adapter->cmd_map) {
1118                 pvscsi_free_sgls(adapter);
1119                 kfree(adapter->cmd_map);
1120         }
1121
1122         if (adapter->rings_state)
1123                 pci_free_consistent(adapter->dev, PAGE_SIZE,
1124                                     adapter->rings_state, adapter->ringStatePA);
1125
1126         if (adapter->req_ring)
1127                 pci_free_consistent(adapter->dev,
1128                                     adapter->req_pages * PAGE_SIZE,
1129                                     adapter->req_ring, adapter->reqRingPA);
1130
1131         if (adapter->cmp_ring)
1132                 pci_free_consistent(adapter->dev,
1133                                     adapter->cmp_pages * PAGE_SIZE,
1134                                     adapter->cmp_ring, adapter->cmpRingPA);
1135
1136         if (adapter->msg_ring)
1137                 pci_free_consistent(adapter->dev,
1138                                     adapter->msg_pages * PAGE_SIZE,
1139                                     adapter->msg_ring, adapter->msgRingPA);
1140 }
1141
1142 /*
1143  * Allocate scatter gather lists.
1144  *
1145  * These are statically allocated.  Trying to be clever was not worth it.
1146  *
1147  * Dynamic allocation can fail, and we can't go deep into the memory
1148  * allocator, since we're a SCSI driver, and trying too hard to allocate
1149  * memory might generate disk I/O.  We also don't want to fail disk I/O
1150  * in that case because we can't get an allocation - the I/O could be
1151  * trying to swap out data to free memory.  Since that is pathological,
1152  * just use a statically allocated scatter list.
1153  *
1154  */
1155 static int __devinit pvscsi_allocate_sg(struct pvscsi_adapter *adapter)
1156 {
1157         struct pvscsi_ctx *ctx;
1158         int i;
1159
1160         ctx = adapter->cmd_map;
1161         BUILD_BUG_ON(sizeof(struct pvscsi_sg_list) > SGL_SIZE);
1162
1163         for (i = 0; i < adapter->req_depth; ++i, ++ctx) {
1164                 ctx->sgl = (void *)__get_free_pages(GFP_KERNEL,
1165                                                     get_order(SGL_SIZE));
1166                 ctx->sglPA = 0;
1167                 BUG_ON(!IS_ALIGNED(((unsigned long)ctx->sgl), PAGE_SIZE));
1168                 if (!ctx->sgl) {
1169                         for (; i >= 0; --i, --ctx) {
1170                                 free_pages((unsigned long)ctx->sgl,
1171                                            get_order(SGL_SIZE));
1172                                 ctx->sgl = NULL;
1173                         }
1174                         return -ENOMEM;
1175                 }
1176         }
1177
1178         return 0;
1179 }
1180
1181 /*
1182  * Query the device, fetch the config info and return the
1183  * maximum number of targets on the adapter. In case of
1184  * failure due to any reason return default i.e. 16.
1185  */
1186 static u32 pvscsi_get_max_targets(struct pvscsi_adapter *adapter)
1187 {
1188         struct PVSCSICmdDescConfigCmd cmd;
1189         struct PVSCSIConfigPageHeader *header;
1190         struct device *dev;
1191         dma_addr_t configPagePA;
1192         void *config_page;
1193         u32 numPhys = 16;
1194
1195         dev = pvscsi_dev(adapter);
1196         config_page = pci_alloc_consistent(adapter->dev, PAGE_SIZE,
1197                                            &configPagePA);
1198         if (!config_page) {
1199                 dev_warn(dev, "vmw_pvscsi: failed to allocate memory for config page\n");
1200                 goto exit;
1201         }
1202         BUG_ON(configPagePA & ~PAGE_MASK);
1203
1204         /* Fetch config info from the device. */
1205         cmd.configPageAddress = ((u64)PVSCSI_CONFIG_CONTROLLER_ADDRESS) << 32;
1206         cmd.configPageNum = PVSCSI_CONFIG_PAGE_CONTROLLER;
1207         cmd.cmpAddr = configPagePA;
1208         cmd._pad = 0;
1209
1210         /*
1211          * Mark the completion page header with error values. If the device
1212          * completes the command successfully, it sets the status values to
1213          * indicate success.
1214          */
1215         header = config_page;
1216         memset(header, 0, sizeof *header);
1217         header->hostStatus = BTSTAT_INVPARAM;
1218         header->scsiStatus = SDSTAT_CHECK;
1219
1220         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_CONFIG, &cmd, sizeof cmd);
1221
1222         if (header->hostStatus == BTSTAT_SUCCESS &&
1223             header->scsiStatus == SDSTAT_GOOD) {
1224                 struct PVSCSIConfigPageController *config;
1225
1226                 config = config_page;
1227                 numPhys = config->numPhys;
1228         } else
1229                 dev_warn(dev, "vmw_pvscsi: PVSCSI_CMD_CONFIG failed. hostStatus = 0x%x, scsiStatus = 0x%x\n",
1230                          header->hostStatus, header->scsiStatus);
1231         pci_free_consistent(adapter->dev, PAGE_SIZE, config_page, configPagePA);
1232 exit:
1233         return numPhys;
1234 }
1235
1236 static int __devinit pvscsi_probe(struct pci_dev *pdev,
1237                                   const struct pci_device_id *id)
1238 {
1239         struct pvscsi_adapter *adapter;
1240         struct Scsi_Host *host;
1241         struct device *dev;
1242         unsigned int i;
1243         unsigned long flags = 0;
1244         int error;
1245
1246         error = -ENODEV;
1247
1248         if (pci_enable_device(pdev))
1249                 return error;
1250
1251         if (pci_set_dma_mask(pdev, DMA_BIT_MASK(64)) == 0 &&
1252             pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64)) == 0) {
1253                 printk(KERN_INFO "vmw_pvscsi: using 64bit dma\n");
1254         } else if (pci_set_dma_mask(pdev, DMA_BIT_MASK(32)) == 0 &&
1255                    pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32)) == 0) {
1256                 printk(KERN_INFO "vmw_pvscsi: using 32bit dma\n");
1257         } else {
1258                 printk(KERN_ERR "vmw_pvscsi: failed to set DMA mask\n");
1259                 goto out_disable_device;
1260         }
1261
1262         pvscsi_template.can_queue =
1263                 min(PVSCSI_MAX_NUM_PAGES_REQ_RING, pvscsi_ring_pages) *
1264                 PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
1265         pvscsi_template.cmd_per_lun =
1266                 min(pvscsi_template.can_queue, pvscsi_cmd_per_lun);
1267         host = scsi_host_alloc(&pvscsi_template, sizeof(struct pvscsi_adapter));
1268         if (!host) {
1269                 printk(KERN_ERR "vmw_pvscsi: failed to allocate host\n");
1270                 goto out_disable_device;
1271         }
1272
1273         adapter = shost_priv(host);
1274         memset(adapter, 0, sizeof(*adapter));
1275         adapter->dev  = pdev;
1276         adapter->host = host;
1277
1278         spin_lock_init(&adapter->hw_lock);
1279
1280         host->max_channel = 0;
1281         host->max_id      = 16;
1282         host->max_lun     = 1;
1283         host->max_cmd_len = 16;
1284
1285         adapter->rev = pdev->revision;
1286
1287         if (pci_request_regions(pdev, "vmw_pvscsi")) {
1288                 printk(KERN_ERR "vmw_pvscsi: pci memory selection failed\n");
1289                 goto out_free_host;
1290         }
1291
1292         for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
1293                 if ((pci_resource_flags(pdev, i) & PCI_BASE_ADDRESS_SPACE_IO))
1294                         continue;
1295
1296                 if (pci_resource_len(pdev, i) < PVSCSI_MEM_SPACE_SIZE)
1297                         continue;
1298
1299                 break;
1300         }
1301
1302         if (i == DEVICE_COUNT_RESOURCE) {
1303                 printk(KERN_ERR
1304                        "vmw_pvscsi: adapter has no suitable MMIO region\n");
1305                 goto out_release_resources;
1306         }
1307
1308         adapter->mmioBase = pci_iomap(pdev, i, PVSCSI_MEM_SPACE_SIZE);
1309
1310         if (!adapter->mmioBase) {
1311                 printk(KERN_ERR
1312                        "vmw_pvscsi: can't iomap for BAR %d memsize %lu\n",
1313                        i, PVSCSI_MEM_SPACE_SIZE);
1314                 goto out_release_resources;
1315         }
1316
1317         pci_set_master(pdev);
1318         pci_set_drvdata(pdev, host);
1319
1320         ll_adapter_reset(adapter);
1321
1322         adapter->use_msg = pvscsi_setup_msg_workqueue(adapter);
1323
1324         error = pvscsi_allocate_rings(adapter);
1325         if (error) {
1326                 printk(KERN_ERR "vmw_pvscsi: unable to allocate ring memory\n");
1327                 goto out_release_resources;
1328         }
1329
1330         /*
1331          * Ask the device for max number of targets.
1332          */
1333         host->max_id = pvscsi_get_max_targets(adapter);
1334         dev = pvscsi_dev(adapter);
1335         dev_info(dev, "vmw_pvscsi: host->max_id: %u\n", host->max_id);
1336
1337         /*
1338          * From this point on we should reset the adapter if anything goes
1339          * wrong.
1340          */
1341         pvscsi_setup_all_rings(adapter);
1342
1343         adapter->cmd_map = kcalloc(adapter->req_depth,
1344                                    sizeof(struct pvscsi_ctx), GFP_KERNEL);
1345         if (!adapter->cmd_map) {
1346                 printk(KERN_ERR "vmw_pvscsi: failed to allocate memory.\n");
1347                 error = -ENOMEM;
1348                 goto out_reset_adapter;
1349         }
1350
1351         INIT_LIST_HEAD(&adapter->cmd_pool);
1352         for (i = 0; i < adapter->req_depth; i++) {
1353                 struct pvscsi_ctx *ctx = adapter->cmd_map + i;
1354                 list_add(&ctx->list, &adapter->cmd_pool);
1355         }
1356
1357         error = pvscsi_allocate_sg(adapter);
1358         if (error) {
1359                 printk(KERN_ERR "vmw_pvscsi: unable to allocate s/g table\n");
1360                 goto out_reset_adapter;
1361         }
1362
1363         if (!pvscsi_disable_msix &&
1364             pvscsi_setup_msix(adapter, &adapter->irq) == 0) {
1365                 printk(KERN_INFO "vmw_pvscsi: using MSI-X\n");
1366                 adapter->use_msix = 1;
1367         } else if (!pvscsi_disable_msi && pci_enable_msi(pdev) == 0) {
1368                 printk(KERN_INFO "vmw_pvscsi: using MSI\n");
1369                 adapter->use_msi = 1;
1370                 adapter->irq = pdev->irq;
1371         } else {
1372                 printk(KERN_INFO "vmw_pvscsi: using INTx\n");
1373                 adapter->irq = pdev->irq;
1374                 flags = IRQF_SHARED;
1375         }
1376
1377         error = request_irq(adapter->irq, pvscsi_isr, flags,
1378                             "vmw_pvscsi", adapter);
1379         if (error) {
1380                 printk(KERN_ERR
1381                        "vmw_pvscsi: unable to request IRQ: %d\n", error);
1382                 adapter->irq = 0;
1383                 goto out_reset_adapter;
1384         }
1385
1386         error = scsi_add_host(host, &pdev->dev);
1387         if (error) {
1388                 printk(KERN_ERR
1389                        "vmw_pvscsi: scsi_add_host failed: %d\n", error);
1390                 goto out_reset_adapter;
1391         }
1392
1393         dev_info(&pdev->dev, "VMware PVSCSI rev %d host #%u\n",
1394                  adapter->rev, host->host_no);
1395
1396         pvscsi_unmask_intr(adapter);
1397
1398         scsi_scan_host(host);
1399
1400         return 0;
1401
1402 out_reset_adapter:
1403         ll_adapter_reset(adapter);
1404 out_release_resources:
1405         pvscsi_release_resources(adapter);
1406 out_free_host:
1407         scsi_host_put(host);
1408 out_disable_device:
1409         pci_set_drvdata(pdev, NULL);
1410         pci_disable_device(pdev);
1411
1412         return error;
1413 }
1414
1415 static void __pvscsi_shutdown(struct pvscsi_adapter *adapter)
1416 {
1417         pvscsi_mask_intr(adapter);
1418
1419         if (adapter->workqueue)
1420                 flush_workqueue(adapter->workqueue);
1421
1422         pvscsi_shutdown_intr(adapter);
1423
1424         pvscsi_process_request_ring(adapter);
1425         pvscsi_process_completion_ring(adapter);
1426         ll_adapter_reset(adapter);
1427 }
1428
1429 static void pvscsi_shutdown(struct pci_dev *dev)
1430 {
1431         struct Scsi_Host *host = pci_get_drvdata(dev);
1432         struct pvscsi_adapter *adapter = shost_priv(host);
1433
1434         __pvscsi_shutdown(adapter);
1435 }
1436
1437 static void pvscsi_remove(struct pci_dev *pdev)
1438 {
1439         struct Scsi_Host *host = pci_get_drvdata(pdev);
1440         struct pvscsi_adapter *adapter = shost_priv(host);
1441
1442         scsi_remove_host(host);
1443
1444         __pvscsi_shutdown(adapter);
1445         pvscsi_release_resources(adapter);
1446
1447         scsi_host_put(host);
1448
1449         pci_set_drvdata(pdev, NULL);
1450         pci_disable_device(pdev);
1451 }
1452
1453 static struct pci_driver pvscsi_pci_driver = {
1454         .name           = "vmw_pvscsi",
1455         .id_table       = pvscsi_pci_tbl,
1456         .probe          = pvscsi_probe,
1457         .remove         = __devexit_p(pvscsi_remove),
1458         .shutdown       = pvscsi_shutdown,
1459 };
1460
1461 static int __init pvscsi_init(void)
1462 {
1463         pr_info("%s - version %s\n",
1464                 PVSCSI_LINUX_DRIVER_DESC, PVSCSI_DRIVER_VERSION_STRING);
1465         return pci_register_driver(&pvscsi_pci_driver);
1466 }
1467
1468 static void __exit pvscsi_exit(void)
1469 {
1470         pci_unregister_driver(&pvscsi_pci_driver);
1471 }
1472
1473 module_init(pvscsi_init);
1474 module_exit(pvscsi_exit);