drivers/scsi/vmw_pvscsi.c

   1 /*
   2  * Linux driver for VMware's para-virtualized SCSI HBA.
   3  *
   4  * Copyright (C) 2008-2014, 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 #include <scsi/scsi_tcq.h>
  36
  37 #include "vmw_pvscsi.h"
  38
  39 #define PVSCSI_LINUX_DRIVER_DESC "VMware PVSCSI driver"
  40
  41 MODULE_DESCRIPTION(PVSCSI_LINUX_DRIVER_DESC);
  42 MODULE_AUTHOR("VMware, Inc.");
  43 MODULE_LICENSE("GPL");
  44 MODULE_VERSION(PVSCSI_DRIVER_VERSION_STRING);
  45
  46 #define PVSCSI_DEFAULT_NUM_PAGES_PER_RING       8
  47 #define PVSCSI_DEFAULT_NUM_PAGES_MSG_RING       1
  48 #define PVSCSI_DEFAULT_QUEUE_DEPTH              254
  49 #define SGL_SIZE                                PAGE_SIZE
  50
  51 struct pvscsi_sg_list {
  52         struct PVSCSISGElement sge[PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT];
  53 };
  54
  55 struct pvscsi_ctx {
  56         /*
  57          * The index of the context in cmd_map serves as the context ID for a
  58          * 1-to-1 mapping completions back to requests.
  59          */
  60         struct scsi_cmnd        *cmd;
  61         struct pvscsi_sg_list   *sgl;
  62         struct list_head        list;
  63         dma_addr_t              dataPA;
  64         dma_addr_t              sensePA;
  65         dma_addr_t              sglPA;
  66         struct completion       *abort_cmp;
  67 };
  68
  69 struct pvscsi_adapter {
  70         char                            *mmioBase;
  71         unsigned int                    irq;
  72         u8                              rev;
  73         bool                            use_msi;
  74         bool                            use_msix;
  75         bool                            use_msg;
  76         bool                            use_req_threshold;
  77
  78         spinlock_t                      hw_lock;
  79
  80         struct workqueue_struct         *workqueue;
  81         struct work_struct              work;
  82
  83         struct PVSCSIRingReqDesc        *req_ring;
  84         unsigned                        req_pages;
  85         unsigned                        req_depth;
  86         dma_addr_t                      reqRingPA;
  87
  88         struct PVSCSIRingCmpDesc        *cmp_ring;
  89         unsigned                        cmp_pages;
  90         dma_addr_t                      cmpRingPA;
  91
  92         struct PVSCSIRingMsgDesc        *msg_ring;
  93         unsigned                        msg_pages;
  94         dma_addr_t                      msgRingPA;
  95
  96         struct PVSCSIRingsState         *rings_state;
  97         dma_addr_t                      ringStatePA;
  98
  99         struct pci_dev                  *dev;
 100         struct Scsi_Host                *host;
 101
 102         struct list_head                cmd_pool;
 103         struct pvscsi_ctx               *cmd_map;
 104 };
 105
 106
 107 /* Command line parameters */
 108 static int pvscsi_ring_pages;
 109 static int pvscsi_msg_ring_pages = PVSCSI_DEFAULT_NUM_PAGES_MSG_RING;
 110 static int pvscsi_cmd_per_lun    = PVSCSI_DEFAULT_QUEUE_DEPTH;
 111 static bool pvscsi_disable_msi;
 112 static bool pvscsi_disable_msix;
 113 static bool pvscsi_use_msg       = true;
 114 static bool pvscsi_use_req_threshold = true;
 115
 116 #define PVSCSI_RW (S_IRUSR | S_IWUSR)
 117
 118 module_param_named(ring_pages, pvscsi_ring_pages, int, PVSCSI_RW);
 119 MODULE_PARM_DESC(ring_pages, "Number of pages per req/cmp ring - (default="
 120                  __stringify(PVSCSI_DEFAULT_NUM_PAGES_PER_RING)
 121                  "[up to 16 targets],"
 122                  __stringify(PVSCSI_SETUP_RINGS_MAX_NUM_PAGES)
 123                  "[for 16+ targets])");
 124
 125 module_param_named(msg_ring_pages, pvscsi_msg_ring_pages, int, PVSCSI_RW);
 126 MODULE_PARM_DESC(msg_ring_pages, "Number of pages for the msg ring - (default="
 127                  __stringify(PVSCSI_DEFAULT_NUM_PAGES_MSG_RING) ")");
 128
 129 module_param_named(cmd_per_lun, pvscsi_cmd_per_lun, int, PVSCSI_RW);
 130 MODULE_PARM_DESC(cmd_per_lun, "Maximum commands per lun - (default="
 131                  __stringify(PVSCSI_DEFAULT_QUEUE_DEPTH) ")");
 132
 133 module_param_named(disable_msi, pvscsi_disable_msi, bool, PVSCSI_RW);
 134 MODULE_PARM_DESC(disable_msi, "Disable MSI use in driver - (default=0)");
 135
 136 module_param_named(disable_msix, pvscsi_disable_msix, bool, PVSCSI_RW);
 137 MODULE_PARM_DESC(disable_msix, "Disable MSI-X use in driver - (default=0)");
 138
 139 module_param_named(use_msg, pvscsi_use_msg, bool, PVSCSI_RW);
 140 MODULE_PARM_DESC(use_msg, "Use msg ring when available - (default=1)");
 141
 142 module_param_named(use_req_threshold, pvscsi_use_req_threshold,
 143                    bool, PVSCSI_RW);
 144 MODULE_PARM_DESC(use_req_threshold, "Use driver-based request coalescing if configured - (default=1)");
 145
 146 static const struct pci_device_id pvscsi_pci_tbl[] = {
 147         { PCI_VDEVICE(VMWARE, PCI_DEVICE_ID_VMWARE_PVSCSI) },
 148         { 0 }
 149 };
 150
 151 MODULE_DEVICE_TABLE(pci, pvscsi_pci_tbl);
 152
 153 static struct device *
 154 pvscsi_dev(const struct pvscsi_adapter *adapter)
 155 {
 156         return &(adapter->dev->dev);
 157 }
 158
 159 static struct pvscsi_ctx *
 160 pvscsi_find_context(const struct pvscsi_adapter *adapter, struct scsi_cmnd *cmd)
 161 {
 162         struct pvscsi_ctx *ctx, *end;
 163
 164         end = &adapter->cmd_map[adapter->req_depth];
 165         for (ctx = adapter->cmd_map; ctx < end; ctx++)
 166                 if (ctx->cmd == cmd)
 167                         return ctx;
 168
 169         return NULL;
 170 }
 171
 172 static struct pvscsi_ctx *
 173 pvscsi_acquire_context(struct pvscsi_adapter *adapter, struct scsi_cmnd *cmd)
 174 {
 175         struct pvscsi_ctx *ctx;
 176
 177         if (list_empty(&adapter->cmd_pool))
 178                 return NULL;
 179
 180         ctx = list_first_entry(&adapter->cmd_pool, struct pvscsi_ctx, list);
 181         ctx->cmd = cmd;
 182         list_del(&ctx->list);
 183
 184         return ctx;
 185 }
 186
 187 static void pvscsi_release_context(struct pvscsi_adapter *adapter,
 188                                    struct pvscsi_ctx *ctx)
 189 {
 190         ctx->cmd = NULL;
 191         ctx->abort_cmp = NULL;
 192         list_add(&ctx->list, &adapter->cmd_pool);
 193 }
 194
 195 /*
 196  * Map a pvscsi_ctx struct to a context ID field value; we map to a simple
 197  * non-zero integer. ctx always points to an entry in cmd_map array, hence
 198  * the return value is always >=1.
 199  */
 200 static u64 pvscsi_map_context(const struct pvscsi_adapter *adapter,
 201                               const struct pvscsi_ctx *ctx)
 202 {
 203         return ctx - adapter->cmd_map + 1;
 204 }
 205
 206 static struct pvscsi_ctx *
 207 pvscsi_get_context(const struct pvscsi_adapter *adapter, u64 context)
 208 {
 209         return &adapter->cmd_map[context - 1];
 210 }
 211
 212 static void pvscsi_reg_write(const struct pvscsi_adapter *adapter,
 213                              u32 offset, u32 val)
 214 {
 215         writel(val, adapter->mmioBase + offset);
 216 }
 217
 218 static u32 pvscsi_reg_read(const struct pvscsi_adapter *adapter, u32 offset)
 219 {
 220         return readl(adapter->mmioBase + offset);
 221 }
 222
 223 static u32 pvscsi_read_intr_status(const struct pvscsi_adapter *adapter)
 224 {
 225         return pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_INTR_STATUS);
 226 }
 227
 228 static void pvscsi_write_intr_status(const struct pvscsi_adapter *adapter,
 229                                      u32 val)
 230 {
 231         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_STATUS, val);
 232 }
 233
 234 static void pvscsi_unmask_intr(const struct pvscsi_adapter *adapter)
 235 {
 236         u32 intr_bits;
 237
 238         intr_bits = PVSCSI_INTR_CMPL_MASK;
 239         if (adapter->use_msg)
 240                 intr_bits |= PVSCSI_INTR_MSG_MASK;
 241
 242         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_MASK, intr_bits);
 243 }
 244
 245 static void pvscsi_mask_intr(const struct pvscsi_adapter *adapter)
 246 {
 247         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_INTR_MASK, 0);
 248 }
 249
 250 static void pvscsi_write_cmd_desc(const struct pvscsi_adapter *adapter,
 251                                   u32 cmd, const void *desc, size_t len)
 252 {
 253         const u32 *ptr = desc;
 254         size_t i;
 255
 256         len /= sizeof(*ptr);
 257         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND, cmd);
 258         for (i = 0; i < len; i++)
 259                 pvscsi_reg_write(adapter,
 260                                  PVSCSI_REG_OFFSET_COMMAND_DATA, ptr[i]);
 261 }
 262
 263 static void pvscsi_abort_cmd(const struct pvscsi_adapter *adapter,
 264                              const struct pvscsi_ctx *ctx)
 265 {
 266         struct PVSCSICmdDescAbortCmd cmd = { 0 };
 267
 268         cmd.target = ctx->cmd->device->id;
 269         cmd.context = pvscsi_map_context(adapter, ctx);
 270
 271         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_ABORT_CMD, &cmd, sizeof(cmd));
 272 }
 273
 274 static void pvscsi_kick_rw_io(const struct pvscsi_adapter *adapter)
 275 {
 276         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_KICK_RW_IO, 0);
 277 }
 278
 279 static void pvscsi_process_request_ring(const struct pvscsi_adapter *adapter)
 280 {
 281         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_KICK_NON_RW_IO, 0);
 282 }
 283
 284 static int scsi_is_rw(unsigned char op)
 285 {
 286         return op == READ_6  || op == WRITE_6 ||
 287                op == READ_10 || op == WRITE_10 ||
 288                op == READ_12 || op == WRITE_12 ||
 289                op == READ_16 || op == WRITE_16;
 290 }
 291
 292 static void pvscsi_kick_io(const struct pvscsi_adapter *adapter,
 293                            unsigned char op)
 294 {
 295         if (scsi_is_rw(op)) {
 296                 struct PVSCSIRingsState *s = adapter->rings_state;
 297
 298                 if (!adapter->use_req_threshold ||
 299                     s->reqProdIdx - s->reqConsIdx >= s->reqCallThreshold)
 300                         pvscsi_kick_rw_io(adapter);
 301         } else {
 302                 pvscsi_process_request_ring(adapter);
 303         }
 304 }
 305
 306 static void ll_adapter_reset(const struct pvscsi_adapter *adapter)
 307 {
 308         dev_dbg(pvscsi_dev(adapter), "Adapter Reset on %p\n", adapter);
 309
 310         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_ADAPTER_RESET, NULL, 0);
 311 }
 312
 313 static void ll_bus_reset(const struct pvscsi_adapter *adapter)
 314 {
 315         dev_dbg(pvscsi_dev(adapter), "Resetting bus on %p\n", adapter);
 316
 317         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_RESET_BUS, NULL, 0);
 318 }
 319
 320 static void ll_device_reset(const struct pvscsi_adapter *adapter, u32 target)
 321 {
 322         struct PVSCSICmdDescResetDevice cmd = { 0 };
 323
 324         dev_dbg(pvscsi_dev(adapter), "Resetting device: target=%u\n", target);
 325
 326         cmd.target = target;
 327
 328         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_RESET_DEVICE,
 329                               &cmd, sizeof(cmd));
 330 }
 331
 332 static void pvscsi_create_sg(struct pvscsi_ctx *ctx,
 333                              struct scatterlist *sg, unsigned count)
 334 {
 335         unsigned i;
 336         struct PVSCSISGElement *sge;
 337
 338         BUG_ON(count > PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT);
 339
 340         sge = &ctx->sgl->sge[0];
 341         for (i = 0; i < count; i++, sg++) {
 342                 sge[i].addr   = sg_dma_address(sg);
 343                 sge[i].length = sg_dma_len(sg);
 344                 sge[i].flags  = 0;
 345         }
 346 }
 347
 348 /*
 349  * Map all data buffers for a command into PCI space and
 350  * setup the scatter/gather list if needed.
 351  */
 352 static void pvscsi_map_buffers(struct pvscsi_adapter *adapter,
 353                                struct pvscsi_ctx *ctx, struct scsi_cmnd *cmd,
 354                                struct PVSCSIRingReqDesc *e)
 355 {
 356         unsigned count;
 357         unsigned bufflen = scsi_bufflen(cmd);
 358         struct scatterlist *sg;
 359
 360         e->dataLen = bufflen;
 361         e->dataAddr = 0;
 362         if (bufflen == 0)
 363                 return;
 364
 365         sg = scsi_sglist(cmd);
 366         count = scsi_sg_count(cmd);
 367         if (count != 0) {
 368                 int segs = scsi_dma_map(cmd);
 369                 if (segs > 1) {
 370                         pvscsi_create_sg(ctx, sg, segs);
 371
 372                         e->flags |= PVSCSI_FLAG_CMD_WITH_SG_LIST;
 373                         ctx->sglPA = pci_map_single(adapter->dev, ctx->sgl,
 374                                                     SGL_SIZE, PCI_DMA_TODEVICE);
 375                         e->dataAddr = ctx->sglPA;
 376                 } else
 377                         e->dataAddr = sg_dma_address(sg);
 378         } else {
 379                 /*
 380                  * In case there is no S/G list, scsi_sglist points
 381                  * directly to the buffer.
 382                  */
 383                 ctx->dataPA = pci_map_single(adapter->dev, sg, bufflen,
 384                                              cmd->sc_data_direction);
 385                 e->dataAddr = ctx->dataPA;
 386         }
 387 }
 388
 389 static void pvscsi_unmap_buffers(const struct pvscsi_adapter *adapter,
 390                                  struct pvscsi_ctx *ctx)
 391 {
 392         struct scsi_cmnd *cmd;
 393         unsigned bufflen;
 394
 395         cmd = ctx->cmd;
 396         bufflen = scsi_bufflen(cmd);
 397
 398         if (bufflen != 0) {
 399                 unsigned count = scsi_sg_count(cmd);
 400
 401                 if (count != 0) {
 402                         scsi_dma_unmap(cmd);
 403                         if (ctx->sglPA) {
 404                                 pci_unmap_single(adapter->dev, ctx->sglPA,
 405                                                  SGL_SIZE, PCI_DMA_TODEVICE);
 406                                 ctx->sglPA = 0;
 407                         }
 408                 } else
 409                         pci_unmap_single(adapter->dev, ctx->dataPA, bufflen,
 410                                          cmd->sc_data_direction);
 411         }
 412         if (cmd->sense_buffer)
 413                 pci_unmap_single(adapter->dev, ctx->sensePA,
 414                                  SCSI_SENSE_BUFFERSIZE, PCI_DMA_FROMDEVICE);
 415 }
 416
 417 static int pvscsi_allocate_rings(struct pvscsi_adapter *adapter)
 418 {
 419         adapter->rings_state = pci_alloc_consistent(adapter->dev, PAGE_SIZE,
 420                                                     &adapter->ringStatePA);
 421         if (!adapter->rings_state)
 422                 return -ENOMEM;
 423
 424         adapter->req_pages = min(PVSCSI_MAX_NUM_PAGES_REQ_RING,
 425                                  pvscsi_ring_pages);
 426         adapter->req_depth = adapter->req_pages
 427                                         * PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
 428         adapter->req_ring = pci_alloc_consistent(adapter->dev,
 429                                                  adapter->req_pages * PAGE_SIZE,
 430                                                  &adapter->reqRingPA);
 431         if (!adapter->req_ring)
 432                 return -ENOMEM;
 433
 434         adapter->cmp_pages = min(PVSCSI_MAX_NUM_PAGES_CMP_RING,
 435                                  pvscsi_ring_pages);
 436         adapter->cmp_ring = pci_alloc_consistent(adapter->dev,
 437                                                  adapter->cmp_pages * PAGE_SIZE,
 438                                                  &adapter->cmpRingPA);
 439         if (!adapter->cmp_ring)
 440                 return -ENOMEM;
 441
 442         BUG_ON(!IS_ALIGNED(adapter->ringStatePA, PAGE_SIZE));
 443         BUG_ON(!IS_ALIGNED(adapter->reqRingPA, PAGE_SIZE));
 444         BUG_ON(!IS_ALIGNED(adapter->cmpRingPA, PAGE_SIZE));
 445
 446         if (!adapter->use_msg)
 447                 return 0;
 448
 449         adapter->msg_pages = min(PVSCSI_MAX_NUM_PAGES_MSG_RING,
 450                                  pvscsi_msg_ring_pages);
 451         adapter->msg_ring = pci_alloc_consistent(adapter->dev,
 452                                                  adapter->msg_pages * PAGE_SIZE,
 453                                                  &adapter->msgRingPA);
 454         if (!adapter->msg_ring)
 455                 return -ENOMEM;
 456         BUG_ON(!IS_ALIGNED(adapter->msgRingPA, PAGE_SIZE));
 457
 458         return 0;
 459 }
 460
 461 static void pvscsi_setup_all_rings(const struct pvscsi_adapter *adapter)
 462 {
 463         struct PVSCSICmdDescSetupRings cmd = { 0 };
 464         dma_addr_t base;
 465         unsigned i;
 466
 467         cmd.ringsStatePPN   = adapter->ringStatePA >> PAGE_SHIFT;
 468         cmd.reqRingNumPages = adapter->req_pages;
 469         cmd.cmpRingNumPages = adapter->cmp_pages;
 470
 471         base = adapter->reqRingPA;
 472         for (i = 0; i < adapter->req_pages; i++) {
 473                 cmd.reqRingPPNs[i] = base >> PAGE_SHIFT;
 474                 base += PAGE_SIZE;
 475         }
 476
 477         base = adapter->cmpRingPA;
 478         for (i = 0; i < adapter->cmp_pages; i++) {
 479                 cmd.cmpRingPPNs[i] = base >> PAGE_SHIFT;
 480                 base += PAGE_SIZE;
 481         }
 482
 483         memset(adapter->rings_state, 0, PAGE_SIZE);
 484         memset(adapter->req_ring, 0, adapter->req_pages * PAGE_SIZE);
 485         memset(adapter->cmp_ring, 0, adapter->cmp_pages * PAGE_SIZE);
 486
 487         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_RINGS,
 488                               &cmd, sizeof(cmd));
 489
 490         if (adapter->use_msg) {
 491                 struct PVSCSICmdDescSetupMsgRing cmd_msg = { 0 };
 492
 493                 cmd_msg.numPages = adapter->msg_pages;
 494
 495                 base = adapter->msgRingPA;
 496                 for (i = 0; i < adapter->msg_pages; i++) {
 497                         cmd_msg.ringPPNs[i] = base >> PAGE_SHIFT;
 498                         base += PAGE_SIZE;
 499                 }
 500                 memset(adapter->msg_ring, 0, adapter->msg_pages * PAGE_SIZE);
 501
 502                 pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_MSG_RING,
 503                                       &cmd_msg, sizeof(cmd_msg));
 504         }
 505 }
 506
 507 static int pvscsi_change_queue_depth(struct scsi_device *sdev,
 508                                      int qdepth,
 509                                      int reason)
 510 {
 511         int max_depth;
 512         struct Scsi_Host *shost = sdev->host;
 513
 514         if (reason != SCSI_QDEPTH_DEFAULT)
 515                 /*
 516                  * We support only changing default.
 517                  */
 518                 return -EOPNOTSUPP;
 519
 520         max_depth = shost->can_queue;
 521         if (!sdev->tagged_supported)
 522                 max_depth = 1;
 523         if (qdepth > max_depth)
 524                 qdepth = max_depth;
 525         scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), qdepth);
 526
 527         if (sdev->inquiry_len > 7)
 528                 sdev_printk(KERN_INFO, sdev,
 529                             "qdepth(%d), tagged(%d), simple(%d), ordered(%d), scsi_level(%d), cmd_que(%d)\n",
 530                             sdev->queue_depth, sdev->tagged_supported,
 531                             sdev->simple_tags, sdev->ordered_tags,
 532                             sdev->scsi_level, (sdev->inquiry[7] & 2) >> 1);
 533         return sdev->queue_depth;
 534 }
 535
 536 /*
 537  * Pull a completion descriptor off and pass the completion back
 538  * to the SCSI mid layer.
 539  */
 540 static void pvscsi_complete_request(struct pvscsi_adapter *adapter,
 541                                     const struct PVSCSIRingCmpDesc *e)
 542 {
 543         struct pvscsi_ctx *ctx;
 544         struct scsi_cmnd *cmd;
 545         struct completion *abort_cmp;
 546         u32 btstat = e->hostStatus;
 547         u32 sdstat = e->scsiStatus;
 548
 549         ctx = pvscsi_get_context(adapter, e->context);
 550         cmd = ctx->cmd;
 551         abort_cmp = ctx->abort_cmp;
 552         pvscsi_unmap_buffers(adapter, ctx);
 553         pvscsi_release_context(adapter, ctx);
 554         if (abort_cmp) {
 555                 /*
 556                  * The command was requested to be aborted. Just signal that
 557                  * the request completed and swallow the actual cmd completion
 558                  * here. The abort handler will post a completion for this
 559                  * command indicating that it got successfully aborted.
 560                  */
 561                 complete(abort_cmp);
 562                 return;
 563         }
 564
 565         cmd->result = 0;
 566         if (sdstat != SAM_STAT_GOOD &&
 567             (btstat == BTSTAT_SUCCESS ||
 568              btstat == BTSTAT_LINKED_COMMAND_COMPLETED ||
 569              btstat == BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG)) {
 570                 cmd->result = (DID_OK << 16) | sdstat;
 571                 if (sdstat == SAM_STAT_CHECK_CONDITION && cmd->sense_buffer)
 572                         cmd->result |= (DRIVER_SENSE << 24);
 573         } else
 574                 switch (btstat) {
 575                 case BTSTAT_SUCCESS:
 576                 case BTSTAT_LINKED_COMMAND_COMPLETED:
 577                 case BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG:
 578                         /* If everything went fine, let's move on..  */
 579                         cmd->result = (DID_OK << 16);
 580                         break;
 581
 582                 case BTSTAT_DATARUN:
 583                 case BTSTAT_DATA_UNDERRUN:
 584                         /* Report residual data in underruns */
 585                         scsi_set_resid(cmd, scsi_bufflen(cmd) - e->dataLen);
 586                         cmd->result = (DID_ERROR << 16);
 587                         break;
 588
 589                 case BTSTAT_SELTIMEO:
 590                         /* Our emulation returns this for non-connected devs */
 591                         cmd->result = (DID_BAD_TARGET << 16);
 592                         break;
 593
 594                 case BTSTAT_LUNMISMATCH:
 595                 case BTSTAT_TAGREJECT:
 596                 case BTSTAT_BADMSG:
 597                         cmd->result = (DRIVER_INVALID << 24);
 598                         /* fall through */
 599
 600                 case BTSTAT_HAHARDWARE:
 601                 case BTSTAT_INVPHASE:
 602                 case BTSTAT_HATIMEOUT:
 603                 case BTSTAT_NORESPONSE:
 604                 case BTSTAT_DISCONNECT:
 605                 case BTSTAT_HASOFTWARE:
 606                 case BTSTAT_BUSFREE:
 607                 case BTSTAT_SENSFAILED:
 608                         cmd->result |= (DID_ERROR << 16);
 609                         break;
 610
 611                 case BTSTAT_SENTRST:
 612                 case BTSTAT_RECVRST:
 613                 case BTSTAT_BUSRESET:
 614                         cmd->result = (DID_RESET << 16);
 615                         break;
 616
 617                 case BTSTAT_ABORTQUEUE:
 618                         cmd->result = (DID_ABORT << 16);
 619                         break;
 620
 621                 case BTSTAT_SCSIPARITY:
 622                         cmd->result = (DID_PARITY << 16);
 623                         break;
 624
 625                 default:
 626                         cmd->result = (DID_ERROR << 16);
 627                         scmd_printk(KERN_DEBUG, cmd,
 628                                     "Unknown completion status: 0x%x\n",
 629                                     btstat);
 630         }
 631
 632         dev_dbg(&cmd->device->sdev_gendev,
 633                 "cmd=%p %x ctx=%p result=0x%x status=0x%x,%x\n",
 634                 cmd, cmd->cmnd[0], ctx, cmd->result, btstat, sdstat);
 635
 636         cmd->scsi_done(cmd);
 637 }
 638
 639 /*
 640  * barrier usage : Since the PVSCSI device is emulated, there could be cases
 641  * where we may want to serialize some accesses between the driver and the
 642  * emulation layer. We use compiler barriers instead of the more expensive
 643  * memory barriers because PVSCSI is only supported on X86 which has strong
 644  * memory access ordering.
 645  */
 646 static void pvscsi_process_completion_ring(struct pvscsi_adapter *adapter)
 647 {
 648         struct PVSCSIRingsState *s = adapter->rings_state;
 649         struct PVSCSIRingCmpDesc *ring = adapter->cmp_ring;
 650         u32 cmp_entries = s->cmpNumEntriesLog2;
 651
 652         while (s->cmpConsIdx != s->cmpProdIdx) {
 653                 struct PVSCSIRingCmpDesc *e = ring + (s->cmpConsIdx &
 654                                                       MASK(cmp_entries));
 655                 /*
 656                  * This barrier() ensures that *e is not dereferenced while
 657                  * the device emulation still writes data into the slot.
 658                  * Since the device emulation advances s->cmpProdIdx only after
 659                  * updating the slot we want to check it first.
 660                  */
 661                 barrier();
 662                 pvscsi_complete_request(adapter, e);
 663                 /*
 664                  * This barrier() ensures that compiler doesn't reorder write
 665                  * to s->cmpConsIdx before the read of (*e) inside
 666                  * pvscsi_complete_request. Otherwise, device emulation may
 667                  * overwrite *e before we had a chance to read it.
 668                  */
 669                 barrier();
 670                 s->cmpConsIdx++;
 671         }
 672 }
 673
 674 /*
 675  * Translate a Linux SCSI request into a request ring entry.
 676  */
 677 static int pvscsi_queue_ring(struct pvscsi_adapter *adapter,
 678                              struct pvscsi_ctx *ctx, struct scsi_cmnd *cmd)
 679 {
 680         struct PVSCSIRingsState *s;
 681         struct PVSCSIRingReqDesc *e;
 682         struct scsi_device *sdev;
 683         u32 req_entries;
 684
 685         s = adapter->rings_state;
 686         sdev = cmd->device;
 687         req_entries = s->reqNumEntriesLog2;
 688
 689         /*
 690          * If this condition holds, we might have room on the request ring, but
 691          * we might not have room on the completion ring for the response.
 692          * However, we have already ruled out this possibility - we would not
 693          * have successfully allocated a context if it were true, since we only
 694          * have one context per request entry.  Check for it anyway, since it
 695          * would be a serious bug.
 696          */
 697         if (s->reqProdIdx - s->cmpConsIdx >= 1 << req_entries) {
 698                 scmd_printk(KERN_ERR, cmd, "vmw_pvscsi: "
 699                             "ring full: reqProdIdx=%d cmpConsIdx=%d\n",
 700                             s->reqProdIdx, s->cmpConsIdx);
 701                 return -1;
 702         }
 703
 704         e = adapter->req_ring + (s->reqProdIdx & MASK(req_entries));
 705
 706         e->bus    = sdev->channel;
 707         e->target = sdev->id;
 708         memset(e->lun, 0, sizeof(e->lun));
 709         e->lun[1] = sdev->lun;
 710
 711         if (cmd->sense_buffer) {
 712                 ctx->sensePA = pci_map_single(adapter->dev, cmd->sense_buffer,
 713                                               SCSI_SENSE_BUFFERSIZE,
 714                                               PCI_DMA_FROMDEVICE);
 715                 e->senseAddr = ctx->sensePA;
 716                 e->senseLen = SCSI_SENSE_BUFFERSIZE;
 717         } else {
 718                 e->senseLen  = 0;
 719                 e->senseAddr = 0;
 720         }
 721         e->cdbLen   = cmd->cmd_len;
 722         e->vcpuHint = smp_processor_id();
 723         memcpy(e->cdb, cmd->cmnd, e->cdbLen);
 724
 725         e->tag = SIMPLE_QUEUE_TAG;
 726         if (sdev->tagged_supported &&
 727             (cmd->tag == HEAD_OF_QUEUE_TAG ||
 728              cmd->tag == ORDERED_QUEUE_TAG))
 729                 e->tag = cmd->tag;
 730
 731         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
 732                 e->flags = PVSCSI_FLAG_CMD_DIR_TOHOST;
 733         else if (cmd->sc_data_direction == DMA_TO_DEVICE)
 734                 e->flags = PVSCSI_FLAG_CMD_DIR_TODEVICE;
 735         else if (cmd->sc_data_direction == DMA_NONE)
 736                 e->flags = PVSCSI_FLAG_CMD_DIR_NONE;
 737         else
 738                 e->flags = 0;
 739
 740         pvscsi_map_buffers(adapter, ctx, cmd, e);
 741
 742         e->context = pvscsi_map_context(adapter, ctx);
 743
 744         barrier();
 745
 746         s->reqProdIdx++;
 747
 748         return 0;
 749 }
 750
 751 static int pvscsi_queue_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
 752 {
 753         struct Scsi_Host *host = cmd->device->host;
 754         struct pvscsi_adapter *adapter = shost_priv(host);
 755         struct pvscsi_ctx *ctx;
 756         unsigned long flags;
 757
 758         spin_lock_irqsave(&adapter->hw_lock, flags);
 759
 760         ctx = pvscsi_acquire_context(adapter, cmd);
 761         if (!ctx || pvscsi_queue_ring(adapter, ctx, cmd) != 0) {
 762                 if (ctx)
 763                         pvscsi_release_context(adapter, ctx);
 764                 spin_unlock_irqrestore(&adapter->hw_lock, flags);
 765                 return SCSI_MLQUEUE_HOST_BUSY;
 766         }
 767
 768         cmd->scsi_done = done;
 769
 770         dev_dbg(&cmd->device->sdev_gendev,
 771                 "queued cmd %p, ctx %p, op=%x\n", cmd, ctx, cmd->cmnd[0]);
 772
 773         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 774
 775         pvscsi_kick_io(adapter, cmd->cmnd[0]);
 776
 777         return 0;
 778 }
 779
 780 static DEF_SCSI_QCMD(pvscsi_queue)
 781
 782 static int pvscsi_abort(struct scsi_cmnd *cmd)
 783 {
 784         struct pvscsi_adapter *adapter = shost_priv(cmd->device->host);
 785         struct pvscsi_ctx *ctx;
 786         unsigned long flags;
 787         int result = SUCCESS;
 788         DECLARE_COMPLETION_ONSTACK(abort_cmp);
 789
 790         scmd_printk(KERN_DEBUG, cmd, "task abort on host %u, %p\n",
 791                     adapter->host->host_no, cmd);
 792
 793         spin_lock_irqsave(&adapter->hw_lock, flags);
 794
 795         /*
 796          * Poll the completion ring first - we might be trying to abort
 797          * a command that is waiting to be dispatched in the completion ring.
 798          */
 799         pvscsi_process_completion_ring(adapter);
 800
 801         /*
 802          * If there is no context for the command, it either already succeeded
 803          * or else was never properly issued.  Not our problem.
 804          */
 805         ctx = pvscsi_find_context(adapter, cmd);
 806         if (!ctx) {
 807                 scmd_printk(KERN_DEBUG, cmd, "Failed to abort cmd %p\n", cmd);
 808                 goto out;
 809         }
 810
 811         /*
 812          * Mark that the command has been requested to be aborted and issue
 813          * the abort.
 814          */
 815         ctx->abort_cmp = &abort_cmp;
 816
 817         pvscsi_abort_cmd(adapter, ctx);
 818         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 819         /* Wait for 2 secs for the completion. */
 820         wait_for_completion_timeout(&abort_cmp, msecs_to_jiffies(2000));
 821         spin_lock_irqsave(&adapter->hw_lock, flags);
 822
 823         if (!completion_done(&abort_cmp)) {
 824                 /*
 825                  * Failed to abort the command, unmark the fact that it
 826                  * was requested to be aborted.
 827                  */
 828                 ctx->abort_cmp = NULL;
 829                 result = FAILED;
 830                 scmd_printk(KERN_DEBUG, cmd,
 831                             "Failed to get completion for aborted cmd %p\n",
 832                             cmd);
 833                 goto out;
 834         }
 835
 836         /*
 837          * Successfully aborted the command.
 838          */
 839         cmd->result = (DID_ABORT << 16);
 840         cmd->scsi_done(cmd);
 841
 842 out:
 843         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 844         return result;
 845 }
 846
 847 /*
 848  * Abort all outstanding requests.  This is only safe to use if the completion
 849  * ring will never be walked again or the device has been reset, because it
 850  * destroys the 1-1 mapping between context field passed to emulation and our
 851  * request structure.
 852  */
 853 static void pvscsi_reset_all(struct pvscsi_adapter *adapter)
 854 {
 855         unsigned i;
 856
 857         for (i = 0; i < adapter->req_depth; i++) {
 858                 struct pvscsi_ctx *ctx = &adapter->cmd_map[i];
 859                 struct scsi_cmnd *cmd = ctx->cmd;
 860                 if (cmd) {
 861                         scmd_printk(KERN_ERR, cmd,
 862                                     "Forced reset on cmd %p\n", cmd);
 863                         pvscsi_unmap_buffers(adapter, ctx);
 864                         pvscsi_release_context(adapter, ctx);
 865                         cmd->result = (DID_RESET << 16);
 866                         cmd->scsi_done(cmd);
 867                 }
 868         }
 869 }
 870
 871 static int pvscsi_host_reset(struct scsi_cmnd *cmd)
 872 {
 873         struct Scsi_Host *host = cmd->device->host;
 874         struct pvscsi_adapter *adapter = shost_priv(host);
 875         unsigned long flags;
 876         bool use_msg;
 877
 878         scmd_printk(KERN_INFO, cmd, "SCSI Host reset\n");
 879
 880         spin_lock_irqsave(&adapter->hw_lock, flags);
 881
 882         use_msg = adapter->use_msg;
 883
 884         if (use_msg) {
 885                 adapter->use_msg = 0;
 886                 spin_unlock_irqrestore(&adapter->hw_lock, flags);
 887
 888                 /*
 889                  * Now that we know that the ISR won't add more work on the
 890                  * workqueue we can safely flush any outstanding work.
 891                  */
 892                 flush_workqueue(adapter->workqueue);
 893                 spin_lock_irqsave(&adapter->hw_lock, flags);
 894         }
 895
 896         /*
 897          * We're going to tear down the entire ring structure and set it back
 898          * up, so stalling new requests until all completions are flushed and
 899          * the rings are back in place.
 900          */
 901
 902         pvscsi_process_request_ring(adapter);
 903
 904         ll_adapter_reset(adapter);
 905
 906         /*
 907          * Now process any completions.  Note we do this AFTER adapter reset,
 908          * which is strange, but stops races where completions get posted
 909          * between processing the ring and issuing the reset.  The backend will
 910          * not touch the ring memory after reset, so the immediately pre-reset
 911          * completion ring state is still valid.
 912          */
 913         pvscsi_process_completion_ring(adapter);
 914
 915         pvscsi_reset_all(adapter);
 916         adapter->use_msg = use_msg;
 917         pvscsi_setup_all_rings(adapter);
 918         pvscsi_unmask_intr(adapter);
 919
 920         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 921
 922         return SUCCESS;
 923 }
 924
 925 static int pvscsi_bus_reset(struct scsi_cmnd *cmd)
 926 {
 927         struct Scsi_Host *host = cmd->device->host;
 928         struct pvscsi_adapter *adapter = shost_priv(host);
 929         unsigned long flags;
 930
 931         scmd_printk(KERN_INFO, cmd, "SCSI Bus reset\n");
 932
 933         /*
 934          * We don't want to queue new requests for this bus after
 935          * flushing all pending requests to emulation, since new
 936          * requests could then sneak in during this bus reset phase,
 937          * so take the lock now.
 938          */
 939         spin_lock_irqsave(&adapter->hw_lock, flags);
 940
 941         pvscsi_process_request_ring(adapter);
 942         ll_bus_reset(adapter);
 943         pvscsi_process_completion_ring(adapter);
 944
 945         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 946
 947         return SUCCESS;
 948 }
 949
 950 static int pvscsi_device_reset(struct scsi_cmnd *cmd)
 951 {
 952         struct Scsi_Host *host = cmd->device->host;
 953         struct pvscsi_adapter *adapter = shost_priv(host);
 954         unsigned long flags;
 955
 956         scmd_printk(KERN_INFO, cmd, "SCSI device reset on scsi%u:%u\n",
 957                     host->host_no, cmd->device->id);
 958
 959         /*
 960          * We don't want to queue new requests for this device after flushing
 961          * all pending requests to emulation, since new requests could then
 962          * sneak in during this device reset phase, so take the lock now.
 963          */
 964         spin_lock_irqsave(&adapter->hw_lock, flags);
 965
 966         pvscsi_process_request_ring(adapter);
 967         ll_device_reset(adapter, cmd->device->id);
 968         pvscsi_process_completion_ring(adapter);
 969
 970         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 971
 972         return SUCCESS;
 973 }
 974
 975 static struct scsi_host_template pvscsi_template;
 976
 977 static const char *pvscsi_info(struct Scsi_Host *host)
 978 {
 979         struct pvscsi_adapter *adapter = shost_priv(host);
 980         static char buf[256];
 981
 982         sprintf(buf, "VMware PVSCSI storage adapter rev %d, req/cmp/msg rings: "
 983                 "%u/%u/%u pages, cmd_per_lun=%u", adapter->rev,
 984                 adapter->req_pages, adapter->cmp_pages, adapter->msg_pages,
 985                 pvscsi_template.cmd_per_lun);
 986
 987         return buf;
 988 }
 989
 990 static struct scsi_host_template pvscsi_template = {
 991         .module                         = THIS_MODULE,
 992         .name                           = "VMware PVSCSI Host Adapter",
 993         .proc_name                      = "vmw_pvscsi",
 994         .info                           = pvscsi_info,
 995         .queuecommand                   = pvscsi_queue,
 996         .this_id                        = -1,
 997         .sg_tablesize                   = PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT,
 998         .dma_boundary                   = UINT_MAX,
 999         .max_sectors                    = 0xffff,
1000         .use_clustering                 = ENABLE_CLUSTERING,
1001         .change_queue_depth             = pvscsi_change_queue_depth,
1002         .eh_abort_handler               = pvscsi_abort,
1003         .eh_device_reset_handler        = pvscsi_device_reset,
1004         .eh_bus_reset_handler           = pvscsi_bus_reset,
1005         .eh_host_reset_handler          = pvscsi_host_reset,
1006 };
1007
1008 static void pvscsi_process_msg(const struct pvscsi_adapter *adapter,
1009                                const struct PVSCSIRingMsgDesc *e)
1010 {
1011         struct PVSCSIRingsState *s = adapter->rings_state;
1012         struct Scsi_Host *host = adapter->host;
1013         struct scsi_device *sdev;
1014
1015         printk(KERN_INFO "vmw_pvscsi: msg type: 0x%x - MSG RING: %u/%u (%u) \n",
1016                e->type, s->msgProdIdx, s->msgConsIdx, s->msgNumEntriesLog2);
1017
1018         BUILD_BUG_ON(PVSCSI_MSG_LAST != 2);
1019
1020         if (e->type == PVSCSI_MSG_DEV_ADDED) {
1021                 struct PVSCSIMsgDescDevStatusChanged *desc;
1022                 desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
1023
1024                 printk(KERN_INFO
1025                        "vmw_pvscsi: msg: device added at scsi%u:%u:%u\n",
1026                        desc->bus, desc->target, desc->lun[1]);
1027
1028                 if (!scsi_host_get(host))
1029                         return;
1030
1031                 sdev = scsi_device_lookup(host, desc->bus, desc->target,
1032                                           desc->lun[1]);
1033                 if (sdev) {
1034                         printk(KERN_INFO "vmw_pvscsi: device already exists\n");
1035                         scsi_device_put(sdev);
1036                 } else
1037                         scsi_add_device(adapter->host, desc->bus,
1038                                         desc->target, desc->lun[1]);
1039
1040                 scsi_host_put(host);
1041         } else if (e->type == PVSCSI_MSG_DEV_REMOVED) {
1042                 struct PVSCSIMsgDescDevStatusChanged *desc;
1043                 desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
1044
1045                 printk(KERN_INFO
1046                        "vmw_pvscsi: msg: device removed at scsi%u:%u:%u\n",
1047                        desc->bus, desc->target, desc->lun[1]);
1048
1049                 if (!scsi_host_get(host))
1050                         return;
1051
1052                 sdev = scsi_device_lookup(host, desc->bus, desc->target,
1053                                           desc->lun[1]);
1054                 if (sdev) {
1055                         scsi_remove_device(sdev);
1056                         scsi_device_put(sdev);
1057                 } else
1058                         printk(KERN_INFO
1059                                "vmw_pvscsi: failed to lookup scsi%u:%u:%u\n",
1060                                desc->bus, desc->target, desc->lun[1]);
1061
1062                 scsi_host_put(host);
1063         }
1064 }
1065
1066 static int pvscsi_msg_pending(const struct pvscsi_adapter *adapter)
1067 {
1068         struct PVSCSIRingsState *s = adapter->rings_state;
1069
1070         return s->msgProdIdx != s->msgConsIdx;
1071 }
1072
1073 static void pvscsi_process_msg_ring(const struct pvscsi_adapter *adapter)
1074 {
1075         struct PVSCSIRingsState *s = adapter->rings_state;
1076         struct PVSCSIRingMsgDesc *ring = adapter->msg_ring;
1077         u32 msg_entries = s->msgNumEntriesLog2;
1078
1079         while (pvscsi_msg_pending(adapter)) {
1080                 struct PVSCSIRingMsgDesc *e = ring + (s->msgConsIdx &
1081                                                       MASK(msg_entries));
1082
1083                 barrier();
1084                 pvscsi_process_msg(adapter, e);
1085                 barrier();
1086                 s->msgConsIdx++;
1087         }
1088 }
1089
1090 static void pvscsi_msg_workqueue_handler(struct work_struct *data)
1091 {
1092         struct pvscsi_adapter *adapter;
1093
1094         adapter = container_of(data, struct pvscsi_adapter, work);
1095
1096         pvscsi_process_msg_ring(adapter);
1097 }
1098
1099 static int pvscsi_setup_msg_workqueue(struct pvscsi_adapter *adapter)
1100 {
1101         char name[32];
1102
1103         if (!pvscsi_use_msg)
1104                 return 0;
1105
1106         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND,
1107                          PVSCSI_CMD_SETUP_MSG_RING);
1108
1109         if (pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS) == -1)
1110                 return 0;
1111
1112         snprintf(name, sizeof(name),
1113                  "vmw_pvscsi_wq_%u", adapter->host->host_no);
1114
1115         adapter->workqueue = create_singlethread_workqueue(name);
1116         if (!adapter->workqueue) {
1117                 printk(KERN_ERR "vmw_pvscsi: failed to create work queue\n");
1118                 return 0;
1119         }
1120         INIT_WORK(&adapter->work, pvscsi_msg_workqueue_handler);
1121
1122         return 1;
1123 }
1124
1125 static bool pvscsi_setup_req_threshold(struct pvscsi_adapter *adapter,
1126                                       bool enable)
1127 {
1128         u32 val;
1129
1130         if (!pvscsi_use_req_threshold)
1131                 return false;
1132
1133         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND,
1134                          PVSCSI_CMD_SETUP_REQCALLTHRESHOLD);
1135         val = pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS);
1136         if (val == -1) {
1137                 printk(KERN_INFO "vmw_pvscsi: device does not support req_threshold\n");
1138                 return false;
1139         } else {
1140                 struct PVSCSICmdDescSetupReqCall cmd_msg = { 0 };
1141                 cmd_msg.enable = enable;
1142                 printk(KERN_INFO
1143                        "vmw_pvscsi: %sabling reqCallThreshold\n",
1144                         enable ? "en" : "dis");
1145                 pvscsi_write_cmd_desc(adapter,
1146                                       PVSCSI_CMD_SETUP_REQCALLTHRESHOLD,
1147                                       &cmd_msg, sizeof(cmd_msg));
1148                 return pvscsi_reg_read(adapter,
1149                                        PVSCSI_REG_OFFSET_COMMAND_STATUS) != 0;
1150         }
1151 }
1152
1153 static irqreturn_t pvscsi_isr(int irq, void *devp)
1154 {
1155         struct pvscsi_adapter *adapter = devp;
1156         int handled;
1157
1158         if (adapter->use_msi || adapter->use_msix)
1159                 handled = true;
1160         else {
1161                 u32 val = pvscsi_read_intr_status(adapter);
1162                 handled = (val & PVSCSI_INTR_ALL_SUPPORTED) != 0;
1163                 if (handled)
1164                         pvscsi_write_intr_status(devp, val);
1165         }
1166
1167         if (handled) {
1168                 unsigned long flags;
1169
1170                 spin_lock_irqsave(&adapter->hw_lock, flags);
1171
1172                 pvscsi_process_completion_ring(adapter);
1173                 if (adapter->use_msg && pvscsi_msg_pending(adapter))
1174                         queue_work(adapter->workqueue, &adapter->work);
1175
1176                 spin_unlock_irqrestore(&adapter->hw_lock, flags);
1177         }
1178
1179         return IRQ_RETVAL(handled);
1180 }
1181
1182 static void pvscsi_free_sgls(const struct pvscsi_adapter *adapter)
1183 {
1184         struct pvscsi_ctx *ctx = adapter->cmd_map;
1185         unsigned i;
1186
1187         for (i = 0; i < adapter->req_depth; ++i, ++ctx)
1188                 free_pages((unsigned long)ctx->sgl, get_order(SGL_SIZE));
1189 }
1190
1191 static int pvscsi_setup_msix(const struct pvscsi_adapter *adapter,
1192                              unsigned int *irq)
1193 {
1194         struct msix_entry entry = { 0, PVSCSI_VECTOR_COMPLETION };
1195         int ret;
1196
1197         ret = pci_enable_msix(adapter->dev, &entry, 1);
1198         if (ret)
1199                 return ret;
1200
1201         *irq = entry.vector;
1202
1203         return 0;
1204 }
1205
1206 static void pvscsi_shutdown_intr(struct pvscsi_adapter *adapter)
1207 {
1208         if (adapter->irq) {
1209                 free_irq(adapter->irq, adapter);
1210                 adapter->irq = 0;
1211         }
1212         if (adapter->use_msi) {
1213                 pci_disable_msi(adapter->dev);
1214                 adapter->use_msi = 0;
1215         } else if (adapter->use_msix) {
1216                 pci_disable_msix(adapter->dev);
1217                 adapter->use_msix = 0;
1218         }
1219 }
1220
1221 static void pvscsi_release_resources(struct pvscsi_adapter *adapter)
1222 {
1223         pvscsi_shutdown_intr(adapter);
1224
1225         if (adapter->workqueue)
1226                 destroy_workqueue(adapter->workqueue);
1227
1228         if (adapter->mmioBase)
1229                 pci_iounmap(adapter->dev, adapter->mmioBase);
1230
1231         pci_release_regions(adapter->dev);
1232
1233         if (adapter->cmd_map) {
1234                 pvscsi_free_sgls(adapter);
1235                 kfree(adapter->cmd_map);
1236         }
1237
1238         if (adapter->rings_state)
1239                 pci_free_consistent(adapter->dev, PAGE_SIZE,
1240                                     adapter->rings_state, adapter->ringStatePA);
1241
1242         if (adapter->req_ring)
1243                 pci_free_consistent(adapter->dev,
1244                                     adapter->req_pages * PAGE_SIZE,
1245                                     adapter->req_ring, adapter->reqRingPA);
1246
1247         if (adapter->cmp_ring)
1248                 pci_free_consistent(adapter->dev,
1249                                     adapter->cmp_pages * PAGE_SIZE,
1250                                     adapter->cmp_ring, adapter->cmpRingPA);
1251
1252         if (adapter->msg_ring)
1253                 pci_free_consistent(adapter->dev,
1254                                     adapter->msg_pages * PAGE_SIZE,
1255                                     adapter->msg_ring, adapter->msgRingPA);
1256 }
1257
1258 /*
1259  * Allocate scatter gather lists.
1260  *
1261  * These are statically allocated.  Trying to be clever was not worth it.
1262  *
1263  * Dynamic allocation can fail, and we can't go deep into the memory
1264  * allocator, since we're a SCSI driver, and trying too hard to allocate
1265  * memory might generate disk I/O.  We also don't want to fail disk I/O
1266  * in that case because we can't get an allocation - the I/O could be
1267  * trying to swap out data to free memory.  Since that is pathological,
1268  * just use a statically allocated scatter list.
1269  *
1270  */
1271 static int pvscsi_allocate_sg(struct pvscsi_adapter *adapter)
1272 {
1273         struct pvscsi_ctx *ctx;
1274         int i;
1275
1276         ctx = adapter->cmd_map;
1277         BUILD_BUG_ON(sizeof(struct pvscsi_sg_list) > SGL_SIZE);
1278
1279         for (i = 0; i < adapter->req_depth; ++i, ++ctx) {
1280                 ctx->sgl = (void *)__get_free_pages(GFP_KERNEL,
1281                                                     get_order(SGL_SIZE));
1282                 ctx->sglPA = 0;
1283                 BUG_ON(!IS_ALIGNED(((unsigned long)ctx->sgl), PAGE_SIZE));
1284                 if (!ctx->sgl) {
1285                         for (; i >= 0; --i, --ctx) {
1286                                 free_pages((unsigned long)ctx->sgl,
1287                                            get_order(SGL_SIZE));
1288                                 ctx->sgl = NULL;
1289                         }
1290                         return -ENOMEM;
1291                 }
1292         }
1293
1294         return 0;
1295 }
1296
1297 /*
1298  * Query the device, fetch the config info and return the
1299  * maximum number of targets on the adapter. In case of
1300  * failure due to any reason return default i.e. 16.
1301  */
1302 static u32 pvscsi_get_max_targets(struct pvscsi_adapter *adapter)
1303 {
1304         struct PVSCSICmdDescConfigCmd cmd;
1305         struct PVSCSIConfigPageHeader *header;
1306         struct device *dev;
1307         dma_addr_t configPagePA;
1308         void *config_page;
1309         u32 numPhys = 16;
1310
1311         dev = pvscsi_dev(adapter);
1312         config_page = pci_alloc_consistent(adapter->dev, PAGE_SIZE,
1313                                            &configPagePA);
1314         if (!config_page) {
1315                 dev_warn(dev, "vmw_pvscsi: failed to allocate memory for config page\n");
1316                 goto exit;
1317         }
1318         BUG_ON(configPagePA & ~PAGE_MASK);
1319
1320         /* Fetch config info from the device. */
1321         cmd.configPageAddress = ((u64)PVSCSI_CONFIG_CONTROLLER_ADDRESS) << 32;
1322         cmd.configPageNum = PVSCSI_CONFIG_PAGE_CONTROLLER;
1323         cmd.cmpAddr = configPagePA;
1324         cmd._pad = 0;
1325
1326         /*
1327          * Mark the completion page header with error values. If the device
1328          * completes the command successfully, it sets the status values to
1329          * indicate success.
1330          */
1331         header = config_page;
1332         memset(header, 0, sizeof *header);
1333         header->hostStatus = BTSTAT_INVPARAM;
1334         header->scsiStatus = SDSTAT_CHECK;
1335
1336         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_CONFIG, &cmd, sizeof cmd);
1337
1338         if (header->hostStatus == BTSTAT_SUCCESS &&
1339             header->scsiStatus == SDSTAT_GOOD) {
1340                 struct PVSCSIConfigPageController *config;
1341
1342                 config = config_page;
1343                 numPhys = config->numPhys;
1344         } else
1345                 dev_warn(dev, "vmw_pvscsi: PVSCSI_CMD_CONFIG failed. hostStatus = 0x%x, scsiStatus = 0x%x\n",
1346                          header->hostStatus, header->scsiStatus);
1347         pci_free_consistent(adapter->dev, PAGE_SIZE, config_page, configPagePA);
1348 exit:
1349         return numPhys;
1350 }
1351
1352 static int pvscsi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1353 {
1354         struct pvscsi_adapter *adapter;
1355         struct pvscsi_adapter adapter_temp;
1356         struct Scsi_Host *host = NULL;
1357         unsigned int i;
1358         unsigned long flags = 0;
1359         int error;
1360         u32 max_id;
1361
1362         error = -ENODEV;
1363
1364         if (pci_enable_device(pdev))
1365                 return error;
1366
1367         if (pci_set_dma_mask(pdev, DMA_BIT_MASK(64)) == 0 &&
1368             pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64)) == 0) {
1369                 printk(KERN_INFO "vmw_pvscsi: using 64bit dma\n");
1370         } else if (pci_set_dma_mask(pdev, DMA_BIT_MASK(32)) == 0 &&
1371                    pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32)) == 0) {
1372                 printk(KERN_INFO "vmw_pvscsi: using 32bit dma\n");
1373         } else {
1374                 printk(KERN_ERR "vmw_pvscsi: failed to set DMA mask\n");
1375                 goto out_disable_device;
1376         }
1377
1378         /*
1379          * Let's use a temp pvscsi_adapter struct until we find the number of
1380          * targets on the adapter, after that we will switch to the real
1381          * allocated struct.
1382          */
1383         adapter = &adapter_temp;
1384         memset(adapter, 0, sizeof(*adapter));
1385         adapter->dev  = pdev;
1386         adapter->rev = pdev->revision;
1387
1388         if (pci_request_regions(pdev, "vmw_pvscsi")) {
1389                 printk(KERN_ERR "vmw_pvscsi: pci memory selection failed\n");
1390                 goto out_disable_device;
1391         }
1392
1393         for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
1394                 if ((pci_resource_flags(pdev, i) & PCI_BASE_ADDRESS_SPACE_IO))
1395                         continue;
1396
1397                 if (pci_resource_len(pdev, i) < PVSCSI_MEM_SPACE_SIZE)
1398                         continue;
1399
1400                 break;
1401         }
1402
1403         if (i == DEVICE_COUNT_RESOURCE) {
1404                 printk(KERN_ERR
1405                        "vmw_pvscsi: adapter has no suitable MMIO region\n");
1406                 goto out_release_resources_and_disable;
1407         }
1408
1409         adapter->mmioBase = pci_iomap(pdev, i, PVSCSI_MEM_SPACE_SIZE);
1410
1411         if (!adapter->mmioBase) {
1412                 printk(KERN_ERR
1413                        "vmw_pvscsi: can't iomap for BAR %d memsize %lu\n",
1414                        i, PVSCSI_MEM_SPACE_SIZE);
1415                 goto out_release_resources_and_disable;
1416         }
1417
1418         pci_set_master(pdev);
1419
1420         /*
1421          * Ask the device for max number of targets before deciding the
1422          * default pvscsi_ring_pages value.
1423          */
1424         max_id = pvscsi_get_max_targets(adapter);
1425         printk(KERN_INFO "vmw_pvscsi: max_id: %u\n", max_id);
1426
1427         if (pvscsi_ring_pages == 0)
1428                 /*
1429                  * Set the right default value. Up to 16 it is 8, above it is
1430                  * max.
1431                  */
1432                 pvscsi_ring_pages = (max_id > 16) ?
1433                         PVSCSI_SETUP_RINGS_MAX_NUM_PAGES :
1434                         PVSCSI_DEFAULT_NUM_PAGES_PER_RING;
1435         printk(KERN_INFO
1436                "vmw_pvscsi: setting ring_pages to %d\n",
1437                pvscsi_ring_pages);
1438
1439         pvscsi_template.can_queue =
1440                 min(PVSCSI_MAX_NUM_PAGES_REQ_RING, pvscsi_ring_pages) *
1441                 PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
1442         pvscsi_template.cmd_per_lun =
1443                 min(pvscsi_template.can_queue, pvscsi_cmd_per_lun);
1444         host = scsi_host_alloc(&pvscsi_template, sizeof(struct pvscsi_adapter));
1445         if (!host) {
1446                 printk(KERN_ERR "vmw_pvscsi: failed to allocate host\n");
1447                 goto out_release_resources_and_disable;
1448         }
1449
1450         /*
1451          * Let's use the real pvscsi_adapter struct here onwards.
1452          */
1453         adapter = shost_priv(host);
1454         memset(adapter, 0, sizeof(*adapter));
1455         adapter->dev  = pdev;
1456         adapter->host = host;
1457         /*
1458          * Copy back what we already have to the allocated adapter struct.
1459          */
1460         adapter->rev = adapter_temp.rev;
1461         adapter->mmioBase = adapter_temp.mmioBase;
1462
1463         spin_lock_init(&adapter->hw_lock);
1464         host->max_channel = 0;
1465         host->max_lun     = 1;
1466         host->max_cmd_len = 16;
1467         host->max_id      = max_id;
1468
1469         pci_set_drvdata(pdev, host);
1470
1471         ll_adapter_reset(adapter);
1472
1473         adapter->use_msg = pvscsi_setup_msg_workqueue(adapter);
1474
1475         error = pvscsi_allocate_rings(adapter);
1476         if (error) {
1477                 printk(KERN_ERR "vmw_pvscsi: unable to allocate ring memory\n");
1478                 goto out_release_resources;
1479         }
1480
1481         /*
1482          * From this point on we should reset the adapter if anything goes
1483          * wrong.
1484          */
1485         pvscsi_setup_all_rings(adapter);
1486
1487         adapter->cmd_map = kcalloc(adapter->req_depth,
1488                                    sizeof(struct pvscsi_ctx), GFP_KERNEL);
1489         if (!adapter->cmd_map) {
1490                 printk(KERN_ERR "vmw_pvscsi: failed to allocate memory.\n");
1491                 error = -ENOMEM;
1492                 goto out_reset_adapter;
1493         }
1494
1495         INIT_LIST_HEAD(&adapter->cmd_pool);
1496         for (i = 0; i < adapter->req_depth; i++) {
1497                 struct pvscsi_ctx *ctx = adapter->cmd_map + i;
1498                 list_add(&ctx->list, &adapter->cmd_pool);
1499         }
1500
1501         error = pvscsi_allocate_sg(adapter);
1502         if (error) {
1503                 printk(KERN_ERR "vmw_pvscsi: unable to allocate s/g table\n");
1504                 goto out_reset_adapter;
1505         }
1506
1507         if (!pvscsi_disable_msix &&
1508             pvscsi_setup_msix(adapter, &adapter->irq) == 0) {
1509                 printk(KERN_INFO "vmw_pvscsi: using MSI-X\n");
1510                 adapter->use_msix = 1;
1511         } else if (!pvscsi_disable_msi && pci_enable_msi(pdev) == 0) {
1512                 printk(KERN_INFO "vmw_pvscsi: using MSI\n");
1513                 adapter->use_msi = 1;
1514                 adapter->irq = pdev->irq;
1515         } else {
1516                 printk(KERN_INFO "vmw_pvscsi: using INTx\n");
1517                 adapter->irq = pdev->irq;
1518                 flags = IRQF_SHARED;
1519         }
1520
1521         adapter->use_req_threshold = pvscsi_setup_req_threshold(adapter, true);
1522         printk(KERN_DEBUG "vmw_pvscsi: driver-based request coalescing %sabled\n",
1523                adapter->use_req_threshold ? "en" : "dis");
1524
1525         error = request_irq(adapter->irq, pvscsi_isr, flags,
1526                             "vmw_pvscsi", adapter);
1527         if (error) {
1528                 printk(KERN_ERR
1529                        "vmw_pvscsi: unable to request IRQ: %d\n", error);
1530                 adapter->irq = 0;
1531                 goto out_reset_adapter;
1532         }
1533
1534         error = scsi_add_host(host, &pdev->dev);
1535         if (error) {
1536                 printk(KERN_ERR
1537                        "vmw_pvscsi: scsi_add_host failed: %d\n", error);
1538                 goto out_reset_adapter;
1539         }
1540
1541         dev_info(&pdev->dev, "VMware PVSCSI rev %d host #%u\n",
1542                  adapter->rev, host->host_no);
1543
1544         pvscsi_unmask_intr(adapter);
1545
1546         scsi_scan_host(host);
1547
1548         return 0;
1549
1550 out_reset_adapter:
1551         ll_adapter_reset(adapter);
1552 out_release_resources:
1553         pvscsi_release_resources(adapter);
1554         scsi_host_put(host);
1555 out_disable_device:
1556         pci_disable_device(pdev);
1557
1558         return error;
1559
1560 out_release_resources_and_disable:
1561         pvscsi_release_resources(adapter);
1562         goto out_disable_device;
1563 }
1564
1565 static void __pvscsi_shutdown(struct pvscsi_adapter *adapter)
1566 {
1567         pvscsi_mask_intr(adapter);
1568
1569         if (adapter->workqueue)
1570                 flush_workqueue(adapter->workqueue);
1571
1572         pvscsi_shutdown_intr(adapter);
1573
1574         pvscsi_process_request_ring(adapter);
1575         pvscsi_process_completion_ring(adapter);
1576         ll_adapter_reset(adapter);
1577 }
1578
1579 static void pvscsi_shutdown(struct pci_dev *dev)
1580 {
1581         struct Scsi_Host *host = pci_get_drvdata(dev);
1582         struct pvscsi_adapter *adapter = shost_priv(host);
1583
1584         __pvscsi_shutdown(adapter);
1585 }
1586
1587 static void pvscsi_remove(struct pci_dev *pdev)
1588 {
1589         struct Scsi_Host *host = pci_get_drvdata(pdev);
1590         struct pvscsi_adapter *adapter = shost_priv(host);
1591
1592         scsi_remove_host(host);
1593
1594         __pvscsi_shutdown(adapter);
1595         pvscsi_release_resources(adapter);
1596
1597         scsi_host_put(host);
1598
1599         pci_disable_device(pdev);
1600 }
1601
1602 static struct pci_driver pvscsi_pci_driver = {
1603         .name           = "vmw_pvscsi",
1604         .id_table       = pvscsi_pci_tbl,
1605         .probe          = pvscsi_probe,
1606         .remove         = pvscsi_remove,
1607         .shutdown       = pvscsi_shutdown,
1608 };
1609
1610 static int __init pvscsi_init(void)
1611 {
1612         pr_info("%s - version %s\n",
1613                 PVSCSI_LINUX_DRIVER_DESC, PVSCSI_DRIVER_VERSION_STRING);
1614         return pci_register_driver(&pvscsi_pci_driver);
1615 }
1616
1617 static void __exit pvscsi_exit(void)
1618 {
1619         pci_unregister_driver(&pvscsi_pci_driver);
1620 }
1621
1622 module_init(pvscsi_init);
1623 module_exit(pvscsi_exit);