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: Jim Gill <jgill@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 int 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 0;
 364
 365         sg = scsi_sglist(cmd);
 366         count = scsi_sg_count(cmd);
 367         if (count != 0) {
 368                 int segs = scsi_dma_map(cmd);
 369
 370                 if (segs == -ENOMEM) {
 371                         scmd_printk(KERN_ERR, cmd,
 372                                     "vmw_pvscsi: Failed to map cmd sglist for DMA.\n");
 373                         return -ENOMEM;
 374                 } else if (segs > 1) {
 375                         pvscsi_create_sg(ctx, sg, segs);
 376
 377                         e->flags |= PVSCSI_FLAG_CMD_WITH_SG_LIST;
 378                         ctx->sglPA = pci_map_single(adapter->dev, ctx->sgl,
 379                                                     SGL_SIZE, PCI_DMA_TODEVICE);
 380                         if (pci_dma_mapping_error(adapter->dev, ctx->sglPA)) {
 381                                 scmd_printk(KERN_ERR, cmd,
 382                                             "vmw_pvscsi: Failed to map ctx sglist for DMA.\n");
 383                                 scsi_dma_unmap(cmd);
 384                                 ctx->sglPA = 0;
 385                                 return -ENOMEM;
 386                         }
 387                         e->dataAddr = ctx->sglPA;
 388                 } else
 389                         e->dataAddr = sg_dma_address(sg);
 390         } else {
 391                 /*
 392                  * In case there is no S/G list, scsi_sglist points
 393                  * directly to the buffer.
 394                  */
 395                 ctx->dataPA = pci_map_single(adapter->dev, sg, bufflen,
 396                                              cmd->sc_data_direction);
 397                 if (pci_dma_mapping_error(adapter->dev, ctx->dataPA)) {
 398                         scmd_printk(KERN_ERR, cmd,
 399                                     "vmw_pvscsi: Failed to map direct data buffer for DMA.\n");
 400                         return -ENOMEM;
 401                 }
 402                 e->dataAddr = ctx->dataPA;
 403         }
 404
 405         return 0;
 406 }
 407
 408 static void pvscsi_unmap_buffers(const struct pvscsi_adapter *adapter,
 409                                  struct pvscsi_ctx *ctx)
 410 {
 411         struct scsi_cmnd *cmd;
 412         unsigned bufflen;
 413
 414         cmd = ctx->cmd;
 415         bufflen = scsi_bufflen(cmd);
 416
 417         if (bufflen != 0) {
 418                 unsigned count = scsi_sg_count(cmd);
 419
 420                 if (count != 0) {
 421                         scsi_dma_unmap(cmd);
 422                         if (ctx->sglPA) {
 423                                 pci_unmap_single(adapter->dev, ctx->sglPA,
 424                                                  SGL_SIZE, PCI_DMA_TODEVICE);
 425                                 ctx->sglPA = 0;
 426                         }
 427                 } else
 428                         pci_unmap_single(adapter->dev, ctx->dataPA, bufflen,
 429                                          cmd->sc_data_direction);
 430         }
 431         if (cmd->sense_buffer)
 432                 pci_unmap_single(adapter->dev, ctx->sensePA,
 433                                  SCSI_SENSE_BUFFERSIZE, PCI_DMA_FROMDEVICE);
 434 }
 435
 436 static int pvscsi_allocate_rings(struct pvscsi_adapter *adapter)
 437 {
 438         adapter->rings_state = pci_alloc_consistent(adapter->dev, PAGE_SIZE,
 439                                                     &adapter->ringStatePA);
 440         if (!adapter->rings_state)
 441                 return -ENOMEM;
 442
 443         adapter->req_pages = min(PVSCSI_MAX_NUM_PAGES_REQ_RING,
 444                                  pvscsi_ring_pages);
 445         adapter->req_depth = adapter->req_pages
 446                                         * PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
 447         adapter->req_ring = pci_alloc_consistent(adapter->dev,
 448                                                  adapter->req_pages * PAGE_SIZE,
 449                                                  &adapter->reqRingPA);
 450         if (!adapter->req_ring)
 451                 return -ENOMEM;
 452
 453         adapter->cmp_pages = min(PVSCSI_MAX_NUM_PAGES_CMP_RING,
 454                                  pvscsi_ring_pages);
 455         adapter->cmp_ring = pci_alloc_consistent(adapter->dev,
 456                                                  adapter->cmp_pages * PAGE_SIZE,
 457                                                  &adapter->cmpRingPA);
 458         if (!adapter->cmp_ring)
 459                 return -ENOMEM;
 460
 461         BUG_ON(!IS_ALIGNED(adapter->ringStatePA, PAGE_SIZE));
 462         BUG_ON(!IS_ALIGNED(adapter->reqRingPA, PAGE_SIZE));
 463         BUG_ON(!IS_ALIGNED(adapter->cmpRingPA, PAGE_SIZE));
 464
 465         if (!adapter->use_msg)
 466                 return 0;
 467
 468         adapter->msg_pages = min(PVSCSI_MAX_NUM_PAGES_MSG_RING,
 469                                  pvscsi_msg_ring_pages);
 470         adapter->msg_ring = pci_alloc_consistent(adapter->dev,
 471                                                  adapter->msg_pages * PAGE_SIZE,
 472                                                  &adapter->msgRingPA);
 473         if (!adapter->msg_ring)
 474                 return -ENOMEM;
 475         BUG_ON(!IS_ALIGNED(adapter->msgRingPA, PAGE_SIZE));
 476
 477         return 0;
 478 }
 479
 480 static void pvscsi_setup_all_rings(const struct pvscsi_adapter *adapter)
 481 {
 482         struct PVSCSICmdDescSetupRings cmd = { 0 };
 483         dma_addr_t base;
 484         unsigned i;
 485
 486         cmd.ringsStatePPN   = adapter->ringStatePA >> PAGE_SHIFT;
 487         cmd.reqRingNumPages = adapter->req_pages;
 488         cmd.cmpRingNumPages = adapter->cmp_pages;
 489
 490         base = adapter->reqRingPA;
 491         for (i = 0; i < adapter->req_pages; i++) {
 492                 cmd.reqRingPPNs[i] = base >> PAGE_SHIFT;
 493                 base += PAGE_SIZE;
 494         }
 495
 496         base = adapter->cmpRingPA;
 497         for (i = 0; i < adapter->cmp_pages; i++) {
 498                 cmd.cmpRingPPNs[i] = base >> PAGE_SHIFT;
 499                 base += PAGE_SIZE;
 500         }
 501
 502         memset(adapter->rings_state, 0, PAGE_SIZE);
 503         memset(adapter->req_ring, 0, adapter->req_pages * PAGE_SIZE);
 504         memset(adapter->cmp_ring, 0, adapter->cmp_pages * PAGE_SIZE);
 505
 506         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_RINGS,
 507                               &cmd, sizeof(cmd));
 508
 509         if (adapter->use_msg) {
 510                 struct PVSCSICmdDescSetupMsgRing cmd_msg = { 0 };
 511
 512                 cmd_msg.numPages = adapter->msg_pages;
 513
 514                 base = adapter->msgRingPA;
 515                 for (i = 0; i < adapter->msg_pages; i++) {
 516                         cmd_msg.ringPPNs[i] = base >> PAGE_SHIFT;
 517                         base += PAGE_SIZE;
 518                 }
 519                 memset(adapter->msg_ring, 0, adapter->msg_pages * PAGE_SIZE);
 520
 521                 pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_SETUP_MSG_RING,
 522                                       &cmd_msg, sizeof(cmd_msg));
 523         }
 524 }
 525
 526 static int pvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
 527 {
 528         if (!sdev->tagged_supported)
 529                 qdepth = 1;
 530         return scsi_change_queue_depth(sdev, qdepth);
 531 }
 532
 533 /*
 534  * Pull a completion descriptor off and pass the completion back
 535  * to the SCSI mid layer.
 536  */
 537 static void pvscsi_complete_request(struct pvscsi_adapter *adapter,
 538                                     const struct PVSCSIRingCmpDesc *e)
 539 {
 540         struct pvscsi_ctx *ctx;
 541         struct scsi_cmnd *cmd;
 542         struct completion *abort_cmp;
 543         u32 btstat = e->hostStatus;
 544         u32 sdstat = e->scsiStatus;
 545
 546         ctx = pvscsi_get_context(adapter, e->context);
 547         cmd = ctx->cmd;
 548         abort_cmp = ctx->abort_cmp;
 549         pvscsi_unmap_buffers(adapter, ctx);
 550         pvscsi_release_context(adapter, ctx);
 551         if (abort_cmp) {
 552                 /*
 553                  * The command was requested to be aborted. Just signal that
 554                  * the request completed and swallow the actual cmd completion
 555                  * here. The abort handler will post a completion for this
 556                  * command indicating that it got successfully aborted.
 557                  */
 558                 complete(abort_cmp);
 559                 return;
 560         }
 561
 562         cmd->result = 0;
 563         if (sdstat != SAM_STAT_GOOD &&
 564             (btstat == BTSTAT_SUCCESS ||
 565              btstat == BTSTAT_LINKED_COMMAND_COMPLETED ||
 566              btstat == BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG)) {
 567                 cmd->result = (DID_OK << 16) | sdstat;
 568                 if (sdstat == SAM_STAT_CHECK_CONDITION && cmd->sense_buffer)
 569                         cmd->result |= (DRIVER_SENSE << 24);
 570         } else
 571                 switch (btstat) {
 572                 case BTSTAT_SUCCESS:
 573                 case BTSTAT_LINKED_COMMAND_COMPLETED:
 574                 case BTSTAT_LINKED_COMMAND_COMPLETED_WITH_FLAG:
 575                         /* If everything went fine, let's move on..  */
 576                         cmd->result = (DID_OK << 16);
 577                         break;
 578
 579                 case BTSTAT_DATARUN:
 580                 case BTSTAT_DATA_UNDERRUN:
 581                         /* Report residual data in underruns */
 582                         scsi_set_resid(cmd, scsi_bufflen(cmd) - e->dataLen);
 583                         cmd->result = (DID_ERROR << 16);
 584                         break;
 585
 586                 case BTSTAT_SELTIMEO:
 587                         /* Our emulation returns this for non-connected devs */
 588                         cmd->result = (DID_BAD_TARGET << 16);
 589                         break;
 590
 591                 case BTSTAT_LUNMISMATCH:
 592                 case BTSTAT_TAGREJECT:
 593                 case BTSTAT_BADMSG:
 594                         cmd->result = (DRIVER_INVALID << 24);
 595                         /* fall through */
 596
 597                 case BTSTAT_HAHARDWARE:
 598                 case BTSTAT_INVPHASE:
 599                 case BTSTAT_HATIMEOUT:
 600                 case BTSTAT_NORESPONSE:
 601                 case BTSTAT_DISCONNECT:
 602                 case BTSTAT_HASOFTWARE:
 603                 case BTSTAT_BUSFREE:
 604                 case BTSTAT_SENSFAILED:
 605                         cmd->result |= (DID_ERROR << 16);
 606                         break;
 607
 608                 case BTSTAT_SENTRST:
 609                 case BTSTAT_RECVRST:
 610                 case BTSTAT_BUSRESET:
 611                         cmd->result = (DID_RESET << 16);
 612                         break;
 613
 614                 case BTSTAT_ABORTQUEUE:
 615                         cmd->result = (DID_ABORT << 16);
 616                         break;
 617
 618                 case BTSTAT_SCSIPARITY:
 619                         cmd->result = (DID_PARITY << 16);
 620                         break;
 621
 622                 default:
 623                         cmd->result = (DID_ERROR << 16);
 624                         scmd_printk(KERN_DEBUG, cmd,
 625                                     "Unknown completion status: 0x%x\n",
 626                                     btstat);
 627         }
 628
 629         dev_dbg(&cmd->device->sdev_gendev,
 630                 "cmd=%p %x ctx=%p result=0x%x status=0x%x,%x\n",
 631                 cmd, cmd->cmnd[0], ctx, cmd->result, btstat, sdstat);
 632
 633         cmd->scsi_done(cmd);
 634 }
 635
 636 /*
 637  * barrier usage : Since the PVSCSI device is emulated, there could be cases
 638  * where we may want to serialize some accesses between the driver and the
 639  * emulation layer. We use compiler barriers instead of the more expensive
 640  * memory barriers because PVSCSI is only supported on X86 which has strong
 641  * memory access ordering.
 642  */
 643 static void pvscsi_process_completion_ring(struct pvscsi_adapter *adapter)
 644 {
 645         struct PVSCSIRingsState *s = adapter->rings_state;
 646         struct PVSCSIRingCmpDesc *ring = adapter->cmp_ring;
 647         u32 cmp_entries = s->cmpNumEntriesLog2;
 648
 649         while (s->cmpConsIdx != s->cmpProdIdx) {
 650                 struct PVSCSIRingCmpDesc *e = ring + (s->cmpConsIdx &
 651                                                       MASK(cmp_entries));
 652                 /*
 653                  * This barrier() ensures that *e is not dereferenced while
 654                  * the device emulation still writes data into the slot.
 655                  * Since the device emulation advances s->cmpProdIdx only after
 656                  * updating the slot we want to check it first.
 657                  */
 658                 barrier();
 659                 pvscsi_complete_request(adapter, e);
 660                 /*
 661                  * This barrier() ensures that compiler doesn't reorder write
 662                  * to s->cmpConsIdx before the read of (*e) inside
 663                  * pvscsi_complete_request. Otherwise, device emulation may
 664                  * overwrite *e before we had a chance to read it.
 665                  */
 666                 barrier();
 667                 s->cmpConsIdx++;
 668         }
 669 }
 670
 671 /*
 672  * Translate a Linux SCSI request into a request ring entry.
 673  */
 674 static int pvscsi_queue_ring(struct pvscsi_adapter *adapter,
 675                              struct pvscsi_ctx *ctx, struct scsi_cmnd *cmd)
 676 {
 677         struct PVSCSIRingsState *s;
 678         struct PVSCSIRingReqDesc *e;
 679         struct scsi_device *sdev;
 680         u32 req_entries;
 681
 682         s = adapter->rings_state;
 683         sdev = cmd->device;
 684         req_entries = s->reqNumEntriesLog2;
 685
 686         /*
 687          * If this condition holds, we might have room on the request ring, but
 688          * we might not have room on the completion ring for the response.
 689          * However, we have already ruled out this possibility - we would not
 690          * have successfully allocated a context if it were true, since we only
 691          * have one context per request entry.  Check for it anyway, since it
 692          * would be a serious bug.
 693          */
 694         if (s->reqProdIdx - s->cmpConsIdx >= 1 << req_entries) {
 695                 scmd_printk(KERN_ERR, cmd, "vmw_pvscsi: "
 696                             "ring full: reqProdIdx=%d cmpConsIdx=%d\n",
 697                             s->reqProdIdx, s->cmpConsIdx);
 698                 return -1;
 699         }
 700
 701         e = adapter->req_ring + (s->reqProdIdx & MASK(req_entries));
 702
 703         e->bus    = sdev->channel;
 704         e->target = sdev->id;
 705         memset(e->lun, 0, sizeof(e->lun));
 706         e->lun[1] = sdev->lun;
 707
 708         if (cmd->sense_buffer) {
 709                 ctx->sensePA = pci_map_single(adapter->dev, cmd->sense_buffer,
 710                                               SCSI_SENSE_BUFFERSIZE,
 711                                               PCI_DMA_FROMDEVICE);
 712                 if (pci_dma_mapping_error(adapter->dev, ctx->sensePA)) {
 713                         scmd_printk(KERN_ERR, cmd,
 714                                     "vmw_pvscsi: Failed to map sense buffer for DMA.\n");
 715                         ctx->sensePA = 0;
 716                         return -ENOMEM;
 717                 }
 718                 e->senseAddr = ctx->sensePA;
 719                 e->senseLen = SCSI_SENSE_BUFFERSIZE;
 720         } else {
 721                 e->senseLen  = 0;
 722                 e->senseAddr = 0;
 723         }
 724         e->cdbLen   = cmd->cmd_len;
 725         e->vcpuHint = smp_processor_id();
 726         memcpy(e->cdb, cmd->cmnd, e->cdbLen);
 727
 728         e->tag = SIMPLE_QUEUE_TAG;
 729
 730         if (cmd->sc_data_direction == DMA_FROM_DEVICE)
 731                 e->flags = PVSCSI_FLAG_CMD_DIR_TOHOST;
 732         else if (cmd->sc_data_direction == DMA_TO_DEVICE)
 733                 e->flags = PVSCSI_FLAG_CMD_DIR_TODEVICE;
 734         else if (cmd->sc_data_direction == DMA_NONE)
 735                 e->flags = PVSCSI_FLAG_CMD_DIR_NONE;
 736         else
 737                 e->flags = 0;
 738
 739         if (pvscsi_map_buffers(adapter, ctx, cmd, e) != 0) {
 740                 if (cmd->sense_buffer) {
 741                         pci_unmap_single(adapter->dev, ctx->sensePA,
 742                                          SCSI_SENSE_BUFFERSIZE,
 743                                          PCI_DMA_FROMDEVICE);
 744                         ctx->sensePA = 0;
 745                 }
 746                 return -ENOMEM;
 747         }
 748
 749         e->context = pvscsi_map_context(adapter, ctx);
 750
 751         barrier();
 752
 753         s->reqProdIdx++;
 754
 755         return 0;
 756 }
 757
 758 static int pvscsi_queue_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
 759 {
 760         struct Scsi_Host *host = cmd->device->host;
 761         struct pvscsi_adapter *adapter = shost_priv(host);
 762         struct pvscsi_ctx *ctx;
 763         unsigned long flags;
 764
 765         spin_lock_irqsave(&adapter->hw_lock, flags);
 766
 767         ctx = pvscsi_acquire_context(adapter, cmd);
 768         if (!ctx || pvscsi_queue_ring(adapter, ctx, cmd) != 0) {
 769                 if (ctx)
 770                         pvscsi_release_context(adapter, ctx);
 771                 spin_unlock_irqrestore(&adapter->hw_lock, flags);
 772                 return SCSI_MLQUEUE_HOST_BUSY;
 773         }
 774
 775         cmd->scsi_done = done;
 776
 777         dev_dbg(&cmd->device->sdev_gendev,
 778                 "queued cmd %p, ctx %p, op=%x\n", cmd, ctx, cmd->cmnd[0]);
 779
 780         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 781
 782         pvscsi_kick_io(adapter, cmd->cmnd[0]);
 783
 784         return 0;
 785 }
 786
 787 static DEF_SCSI_QCMD(pvscsi_queue)
 788
 789 static int pvscsi_abort(struct scsi_cmnd *cmd)
 790 {
 791         struct pvscsi_adapter *adapter = shost_priv(cmd->device->host);
 792         struct pvscsi_ctx *ctx;
 793         unsigned long flags;
 794         int result = SUCCESS;
 795         DECLARE_COMPLETION_ONSTACK(abort_cmp);
 796
 797         scmd_printk(KERN_DEBUG, cmd, "task abort on host %u, %p\n",
 798                     adapter->host->host_no, cmd);
 799
 800         spin_lock_irqsave(&adapter->hw_lock, flags);
 801
 802         /*
 803          * Poll the completion ring first - we might be trying to abort
 804          * a command that is waiting to be dispatched in the completion ring.
 805          */
 806         pvscsi_process_completion_ring(adapter);
 807
 808         /*
 809          * If there is no context for the command, it either already succeeded
 810          * or else was never properly issued.  Not our problem.
 811          */
 812         ctx = pvscsi_find_context(adapter, cmd);
 813         if (!ctx) {
 814                 scmd_printk(KERN_DEBUG, cmd, "Failed to abort cmd %p\n", cmd);
 815                 goto out;
 816         }
 817
 818         /*
 819          * Mark that the command has been requested to be aborted and issue
 820          * the abort.
 821          */
 822         ctx->abort_cmp = &abort_cmp;
 823
 824         pvscsi_abort_cmd(adapter, ctx);
 825         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 826         /* Wait for 2 secs for the completion. */
 827         wait_for_completion_timeout(&abort_cmp, msecs_to_jiffies(2000));
 828         spin_lock_irqsave(&adapter->hw_lock, flags);
 829
 830         if (!completion_done(&abort_cmp)) {
 831                 /*
 832                  * Failed to abort the command, unmark the fact that it
 833                  * was requested to be aborted.
 834                  */
 835                 ctx->abort_cmp = NULL;
 836                 result = FAILED;
 837                 scmd_printk(KERN_DEBUG, cmd,
 838                             "Failed to get completion for aborted cmd %p\n",
 839                             cmd);
 840                 goto out;
 841         }
 842
 843         /*
 844          * Successfully aborted the command.
 845          */
 846         cmd->result = (DID_ABORT << 16);
 847         cmd->scsi_done(cmd);
 848
 849 out:
 850         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 851         return result;
 852 }
 853
 854 /*
 855  * Abort all outstanding requests.  This is only safe to use if the completion
 856  * ring will never be walked again or the device has been reset, because it
 857  * destroys the 1-1 mapping between context field passed to emulation and our
 858  * request structure.
 859  */
 860 static void pvscsi_reset_all(struct pvscsi_adapter *adapter)
 861 {
 862         unsigned i;
 863
 864         for (i = 0; i < adapter->req_depth; i++) {
 865                 struct pvscsi_ctx *ctx = &adapter->cmd_map[i];
 866                 struct scsi_cmnd *cmd = ctx->cmd;
 867                 if (cmd) {
 868                         scmd_printk(KERN_ERR, cmd,
 869                                     "Forced reset on cmd %p\n", cmd);
 870                         pvscsi_unmap_buffers(adapter, ctx);
 871                         pvscsi_release_context(adapter, ctx);
 872                         cmd->result = (DID_RESET << 16);
 873                         cmd->scsi_done(cmd);
 874                 }
 875         }
 876 }
 877
 878 static int pvscsi_host_reset(struct scsi_cmnd *cmd)
 879 {
 880         struct Scsi_Host *host = cmd->device->host;
 881         struct pvscsi_adapter *adapter = shost_priv(host);
 882         unsigned long flags;
 883         bool use_msg;
 884
 885         scmd_printk(KERN_INFO, cmd, "SCSI Host reset\n");
 886
 887         spin_lock_irqsave(&adapter->hw_lock, flags);
 888
 889         use_msg = adapter->use_msg;
 890
 891         if (use_msg) {
 892                 adapter->use_msg = 0;
 893                 spin_unlock_irqrestore(&adapter->hw_lock, flags);
 894
 895                 /*
 896                  * Now that we know that the ISR won't add more work on the
 897                  * workqueue we can safely flush any outstanding work.
 898                  */
 899                 flush_workqueue(adapter->workqueue);
 900                 spin_lock_irqsave(&adapter->hw_lock, flags);
 901         }
 902
 903         /*
 904          * We're going to tear down the entire ring structure and set it back
 905          * up, so stalling new requests until all completions are flushed and
 906          * the rings are back in place.
 907          */
 908
 909         pvscsi_process_request_ring(adapter);
 910
 911         ll_adapter_reset(adapter);
 912
 913         /*
 914          * Now process any completions.  Note we do this AFTER adapter reset,
 915          * which is strange, but stops races where completions get posted
 916          * between processing the ring and issuing the reset.  The backend will
 917          * not touch the ring memory after reset, so the immediately pre-reset
 918          * completion ring state is still valid.
 919          */
 920         pvscsi_process_completion_ring(adapter);
 921
 922         pvscsi_reset_all(adapter);
 923         adapter->use_msg = use_msg;
 924         pvscsi_setup_all_rings(adapter);
 925         pvscsi_unmask_intr(adapter);
 926
 927         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 928
 929         return SUCCESS;
 930 }
 931
 932 static int pvscsi_bus_reset(struct scsi_cmnd *cmd)
 933 {
 934         struct Scsi_Host *host = cmd->device->host;
 935         struct pvscsi_adapter *adapter = shost_priv(host);
 936         unsigned long flags;
 937
 938         scmd_printk(KERN_INFO, cmd, "SCSI Bus reset\n");
 939
 940         /*
 941          * We don't want to queue new requests for this bus after
 942          * flushing all pending requests to emulation, since new
 943          * requests could then sneak in during this bus reset phase,
 944          * so take the lock now.
 945          */
 946         spin_lock_irqsave(&adapter->hw_lock, flags);
 947
 948         pvscsi_process_request_ring(adapter);
 949         ll_bus_reset(adapter);
 950         pvscsi_process_completion_ring(adapter);
 951
 952         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 953
 954         return SUCCESS;
 955 }
 956
 957 static int pvscsi_device_reset(struct scsi_cmnd *cmd)
 958 {
 959         struct Scsi_Host *host = cmd->device->host;
 960         struct pvscsi_adapter *adapter = shost_priv(host);
 961         unsigned long flags;
 962
 963         scmd_printk(KERN_INFO, cmd, "SCSI device reset on scsi%u:%u\n",
 964                     host->host_no, cmd->device->id);
 965
 966         /*
 967          * We don't want to queue new requests for this device after flushing
 968          * all pending requests to emulation, since new requests could then
 969          * sneak in during this device reset phase, so take the lock now.
 970          */
 971         spin_lock_irqsave(&adapter->hw_lock, flags);
 972
 973         pvscsi_process_request_ring(adapter);
 974         ll_device_reset(adapter, cmd->device->id);
 975         pvscsi_process_completion_ring(adapter);
 976
 977         spin_unlock_irqrestore(&adapter->hw_lock, flags);
 978
 979         return SUCCESS;
 980 }
 981
 982 static struct scsi_host_template pvscsi_template;
 983
 984 static const char *pvscsi_info(struct Scsi_Host *host)
 985 {
 986         struct pvscsi_adapter *adapter = shost_priv(host);
 987         static char buf[256];
 988
 989         sprintf(buf, "VMware PVSCSI storage adapter rev %d, req/cmp/msg rings: "
 990                 "%u/%u/%u pages, cmd_per_lun=%u", adapter->rev,
 991                 adapter->req_pages, adapter->cmp_pages, adapter->msg_pages,
 992                 pvscsi_template.cmd_per_lun);
 993
 994         return buf;
 995 }
 996
 997 static struct scsi_host_template pvscsi_template = {
 998         .module                         = THIS_MODULE,
 999         .name                           = "VMware PVSCSI Host Adapter",
1000         .proc_name                      = "vmw_pvscsi",
1001         .info                           = pvscsi_info,
1002         .queuecommand                   = pvscsi_queue,
1003         .this_id                        = -1,
1004         .sg_tablesize                   = PVSCSI_MAX_NUM_SG_ENTRIES_PER_SEGMENT,
1005         .dma_boundary                   = UINT_MAX,
1006         .max_sectors                    = 0xffff,
1007         .use_clustering                 = ENABLE_CLUSTERING,
1008         .change_queue_depth             = pvscsi_change_queue_depth,
1009         .eh_abort_handler               = pvscsi_abort,
1010         .eh_device_reset_handler        = pvscsi_device_reset,
1011         .eh_bus_reset_handler           = pvscsi_bus_reset,
1012         .eh_host_reset_handler          = pvscsi_host_reset,
1013 };
1014
1015 static void pvscsi_process_msg(const struct pvscsi_adapter *adapter,
1016                                const struct PVSCSIRingMsgDesc *e)
1017 {
1018         struct PVSCSIRingsState *s = adapter->rings_state;
1019         struct Scsi_Host *host = adapter->host;
1020         struct scsi_device *sdev;
1021
1022         printk(KERN_INFO "vmw_pvscsi: msg type: 0x%x - MSG RING: %u/%u (%u) \n",
1023                e->type, s->msgProdIdx, s->msgConsIdx, s->msgNumEntriesLog2);
1024
1025         BUILD_BUG_ON(PVSCSI_MSG_LAST != 2);
1026
1027         if (e->type == PVSCSI_MSG_DEV_ADDED) {
1028                 struct PVSCSIMsgDescDevStatusChanged *desc;
1029                 desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
1030
1031                 printk(KERN_INFO
1032                        "vmw_pvscsi: msg: device added at scsi%u:%u:%u\n",
1033                        desc->bus, desc->target, desc->lun[1]);
1034
1035                 if (!scsi_host_get(host))
1036                         return;
1037
1038                 sdev = scsi_device_lookup(host, desc->bus, desc->target,
1039                                           desc->lun[1]);
1040                 if (sdev) {
1041                         printk(KERN_INFO "vmw_pvscsi: device already exists\n");
1042                         scsi_device_put(sdev);
1043                 } else
1044                         scsi_add_device(adapter->host, desc->bus,
1045                                         desc->target, desc->lun[1]);
1046
1047                 scsi_host_put(host);
1048         } else if (e->type == PVSCSI_MSG_DEV_REMOVED) {
1049                 struct PVSCSIMsgDescDevStatusChanged *desc;
1050                 desc = (struct PVSCSIMsgDescDevStatusChanged *)e;
1051
1052                 printk(KERN_INFO
1053                        "vmw_pvscsi: msg: device removed at scsi%u:%u:%u\n",
1054                        desc->bus, desc->target, desc->lun[1]);
1055
1056                 if (!scsi_host_get(host))
1057                         return;
1058
1059                 sdev = scsi_device_lookup(host, desc->bus, desc->target,
1060                                           desc->lun[1]);
1061                 if (sdev) {
1062                         scsi_remove_device(sdev);
1063                         scsi_device_put(sdev);
1064                 } else
1065                         printk(KERN_INFO
1066                                "vmw_pvscsi: failed to lookup scsi%u:%u:%u\n",
1067                                desc->bus, desc->target, desc->lun[1]);
1068
1069                 scsi_host_put(host);
1070         }
1071 }
1072
1073 static int pvscsi_msg_pending(const struct pvscsi_adapter *adapter)
1074 {
1075         struct PVSCSIRingsState *s = adapter->rings_state;
1076
1077         return s->msgProdIdx != s->msgConsIdx;
1078 }
1079
1080 static void pvscsi_process_msg_ring(const struct pvscsi_adapter *adapter)
1081 {
1082         struct PVSCSIRingsState *s = adapter->rings_state;
1083         struct PVSCSIRingMsgDesc *ring = adapter->msg_ring;
1084         u32 msg_entries = s->msgNumEntriesLog2;
1085
1086         while (pvscsi_msg_pending(adapter)) {
1087                 struct PVSCSIRingMsgDesc *e = ring + (s->msgConsIdx &
1088                                                       MASK(msg_entries));
1089
1090                 barrier();
1091                 pvscsi_process_msg(adapter, e);
1092                 barrier();
1093                 s->msgConsIdx++;
1094         }
1095 }
1096
1097 static void pvscsi_msg_workqueue_handler(struct work_struct *data)
1098 {
1099         struct pvscsi_adapter *adapter;
1100
1101         adapter = container_of(data, struct pvscsi_adapter, work);
1102
1103         pvscsi_process_msg_ring(adapter);
1104 }
1105
1106 static int pvscsi_setup_msg_workqueue(struct pvscsi_adapter *adapter)
1107 {
1108         char name[32];
1109
1110         if (!pvscsi_use_msg)
1111                 return 0;
1112
1113         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND,
1114                          PVSCSI_CMD_SETUP_MSG_RING);
1115
1116         if (pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS) == -1)
1117                 return 0;
1118
1119         snprintf(name, sizeof(name),
1120                  "vmw_pvscsi_wq_%u", adapter->host->host_no);
1121
1122         adapter->workqueue = create_singlethread_workqueue(name);
1123         if (!adapter->workqueue) {
1124                 printk(KERN_ERR "vmw_pvscsi: failed to create work queue\n");
1125                 return 0;
1126         }
1127         INIT_WORK(&adapter->work, pvscsi_msg_workqueue_handler);
1128
1129         return 1;
1130 }
1131
1132 static bool pvscsi_setup_req_threshold(struct pvscsi_adapter *adapter,
1133                                       bool enable)
1134 {
1135         u32 val;
1136
1137         if (!pvscsi_use_req_threshold)
1138                 return false;
1139
1140         pvscsi_reg_write(adapter, PVSCSI_REG_OFFSET_COMMAND,
1141                          PVSCSI_CMD_SETUP_REQCALLTHRESHOLD);
1142         val = pvscsi_reg_read(adapter, PVSCSI_REG_OFFSET_COMMAND_STATUS);
1143         if (val == -1) {
1144                 printk(KERN_INFO "vmw_pvscsi: device does not support req_threshold\n");
1145                 return false;
1146         } else {
1147                 struct PVSCSICmdDescSetupReqCall cmd_msg = { 0 };
1148                 cmd_msg.enable = enable;
1149                 printk(KERN_INFO
1150                        "vmw_pvscsi: %sabling reqCallThreshold\n",
1151                         enable ? "en" : "dis");
1152                 pvscsi_write_cmd_desc(adapter,
1153                                       PVSCSI_CMD_SETUP_REQCALLTHRESHOLD,
1154                                       &cmd_msg, sizeof(cmd_msg));
1155                 return pvscsi_reg_read(adapter,
1156                                        PVSCSI_REG_OFFSET_COMMAND_STATUS) != 0;
1157         }
1158 }
1159
1160 static irqreturn_t pvscsi_isr(int irq, void *devp)
1161 {
1162         struct pvscsi_adapter *adapter = devp;
1163         int handled;
1164
1165         if (adapter->use_msi || adapter->use_msix)
1166                 handled = true;
1167         else {
1168                 u32 val = pvscsi_read_intr_status(adapter);
1169                 handled = (val & PVSCSI_INTR_ALL_SUPPORTED) != 0;
1170                 if (handled)
1171                         pvscsi_write_intr_status(devp, val);
1172         }
1173
1174         if (handled) {
1175                 unsigned long flags;
1176
1177                 spin_lock_irqsave(&adapter->hw_lock, flags);
1178
1179                 pvscsi_process_completion_ring(adapter);
1180                 if (adapter->use_msg && pvscsi_msg_pending(adapter))
1181                         queue_work(adapter->workqueue, &adapter->work);
1182
1183                 spin_unlock_irqrestore(&adapter->hw_lock, flags);
1184         }
1185
1186         return IRQ_RETVAL(handled);
1187 }
1188
1189 static void pvscsi_free_sgls(const struct pvscsi_adapter *adapter)
1190 {
1191         struct pvscsi_ctx *ctx = adapter->cmd_map;
1192         unsigned i;
1193
1194         for (i = 0; i < adapter->req_depth; ++i, ++ctx)
1195                 free_pages((unsigned long)ctx->sgl, get_order(SGL_SIZE));
1196 }
1197
1198 static int pvscsi_setup_msix(const struct pvscsi_adapter *adapter,
1199                              unsigned int *irq)
1200 {
1201         struct msix_entry entry = { 0, PVSCSI_VECTOR_COMPLETION };
1202         int ret;
1203
1204         ret = pci_enable_msix_exact(adapter->dev, &entry, 1);
1205         if (ret)
1206                 return ret;
1207
1208         *irq = entry.vector;
1209
1210         return 0;
1211 }
1212
1213 static void pvscsi_shutdown_intr(struct pvscsi_adapter *adapter)
1214 {
1215         if (adapter->irq) {
1216                 free_irq(adapter->irq, adapter);
1217                 adapter->irq = 0;
1218         }
1219         if (adapter->use_msi) {
1220                 pci_disable_msi(adapter->dev);
1221                 adapter->use_msi = 0;
1222         } else if (adapter->use_msix) {
1223                 pci_disable_msix(adapter->dev);
1224                 adapter->use_msix = 0;
1225         }
1226 }
1227
1228 static void pvscsi_release_resources(struct pvscsi_adapter *adapter)
1229 {
1230         pvscsi_shutdown_intr(adapter);
1231
1232         if (adapter->workqueue)
1233                 destroy_workqueue(adapter->workqueue);
1234
1235         if (adapter->mmioBase)
1236                 pci_iounmap(adapter->dev, adapter->mmioBase);
1237
1238         pci_release_regions(adapter->dev);
1239
1240         if (adapter->cmd_map) {
1241                 pvscsi_free_sgls(adapter);
1242                 kfree(adapter->cmd_map);
1243         }
1244
1245         if (adapter->rings_state)
1246                 pci_free_consistent(adapter->dev, PAGE_SIZE,
1247                                     adapter->rings_state, adapter->ringStatePA);
1248
1249         if (adapter->req_ring)
1250                 pci_free_consistent(adapter->dev,
1251                                     adapter->req_pages * PAGE_SIZE,
1252                                     adapter->req_ring, adapter->reqRingPA);
1253
1254         if (adapter->cmp_ring)
1255                 pci_free_consistent(adapter->dev,
1256                                     adapter->cmp_pages * PAGE_SIZE,
1257                                     adapter->cmp_ring, adapter->cmpRingPA);
1258
1259         if (adapter->msg_ring)
1260                 pci_free_consistent(adapter->dev,
1261                                     adapter->msg_pages * PAGE_SIZE,
1262                                     adapter->msg_ring, adapter->msgRingPA);
1263 }
1264
1265 /*
1266  * Allocate scatter gather lists.
1267  *
1268  * These are statically allocated.  Trying to be clever was not worth it.
1269  *
1270  * Dynamic allocation can fail, and we can't go deep into the memory
1271  * allocator, since we're a SCSI driver, and trying too hard to allocate
1272  * memory might generate disk I/O.  We also don't want to fail disk I/O
1273  * in that case because we can't get an allocation - the I/O could be
1274  * trying to swap out data to free memory.  Since that is pathological,
1275  * just use a statically allocated scatter list.
1276  *
1277  */
1278 static int pvscsi_allocate_sg(struct pvscsi_adapter *adapter)
1279 {
1280         struct pvscsi_ctx *ctx;
1281         int i;
1282
1283         ctx = adapter->cmd_map;
1284         BUILD_BUG_ON(sizeof(struct pvscsi_sg_list) > SGL_SIZE);
1285
1286         for (i = 0; i < adapter->req_depth; ++i, ++ctx) {
1287                 ctx->sgl = (void *)__get_free_pages(GFP_KERNEL,
1288                                                     get_order(SGL_SIZE));
1289                 ctx->sglPA = 0;
1290                 BUG_ON(!IS_ALIGNED(((unsigned long)ctx->sgl), PAGE_SIZE));
1291                 if (!ctx->sgl) {
1292                         for (; i >= 0; --i, --ctx) {
1293                                 free_pages((unsigned long)ctx->sgl,
1294                                            get_order(SGL_SIZE));
1295                                 ctx->sgl = NULL;
1296                         }
1297                         return -ENOMEM;
1298                 }
1299         }
1300
1301         return 0;
1302 }
1303
1304 /*
1305  * Query the device, fetch the config info and return the
1306  * maximum number of targets on the adapter. In case of
1307  * failure due to any reason return default i.e. 16.
1308  */
1309 static u32 pvscsi_get_max_targets(struct pvscsi_adapter *adapter)
1310 {
1311         struct PVSCSICmdDescConfigCmd cmd;
1312         struct PVSCSIConfigPageHeader *header;
1313         struct device *dev;
1314         dma_addr_t configPagePA;
1315         void *config_page;
1316         u32 numPhys = 16;
1317
1318         dev = pvscsi_dev(adapter);
1319         config_page = pci_alloc_consistent(adapter->dev, PAGE_SIZE,
1320                                            &configPagePA);
1321         if (!config_page) {
1322                 dev_warn(dev, "vmw_pvscsi: failed to allocate memory for config page\n");
1323                 goto exit;
1324         }
1325         BUG_ON(configPagePA & ~PAGE_MASK);
1326
1327         /* Fetch config info from the device. */
1328         cmd.configPageAddress = ((u64)PVSCSI_CONFIG_CONTROLLER_ADDRESS) << 32;
1329         cmd.configPageNum = PVSCSI_CONFIG_PAGE_CONTROLLER;
1330         cmd.cmpAddr = configPagePA;
1331         cmd._pad = 0;
1332
1333         /*
1334          * Mark the completion page header with error values. If the device
1335          * completes the command successfully, it sets the status values to
1336          * indicate success.
1337          */
1338         header = config_page;
1339         memset(header, 0, sizeof *header);
1340         header->hostStatus = BTSTAT_INVPARAM;
1341         header->scsiStatus = SDSTAT_CHECK;
1342
1343         pvscsi_write_cmd_desc(adapter, PVSCSI_CMD_CONFIG, &cmd, sizeof cmd);
1344
1345         if (header->hostStatus == BTSTAT_SUCCESS &&
1346             header->scsiStatus == SDSTAT_GOOD) {
1347                 struct PVSCSIConfigPageController *config;
1348
1349                 config = config_page;
1350                 numPhys = config->numPhys;
1351         } else
1352                 dev_warn(dev, "vmw_pvscsi: PVSCSI_CMD_CONFIG failed. hostStatus = 0x%x, scsiStatus = 0x%x\n",
1353                          header->hostStatus, header->scsiStatus);
1354         pci_free_consistent(adapter->dev, PAGE_SIZE, config_page, configPagePA);
1355 exit:
1356         return numPhys;
1357 }
1358
1359 static int pvscsi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
1360 {
1361         struct pvscsi_adapter *adapter;
1362         struct pvscsi_adapter adapter_temp;
1363         struct Scsi_Host *host = NULL;
1364         unsigned int i;
1365         unsigned long flags = 0;
1366         int error;
1367         u32 max_id;
1368
1369         error = -ENODEV;
1370
1371         if (pci_enable_device(pdev))
1372                 return error;
1373
1374         if (pci_set_dma_mask(pdev, DMA_BIT_MASK(64)) == 0 &&
1375             pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64)) == 0) {
1376                 printk(KERN_INFO "vmw_pvscsi: using 64bit dma\n");
1377         } else if (pci_set_dma_mask(pdev, DMA_BIT_MASK(32)) == 0 &&
1378                    pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32)) == 0) {
1379                 printk(KERN_INFO "vmw_pvscsi: using 32bit dma\n");
1380         } else {
1381                 printk(KERN_ERR "vmw_pvscsi: failed to set DMA mask\n");
1382                 goto out_disable_device;
1383         }
1384
1385         /*
1386          * Let's use a temp pvscsi_adapter struct until we find the number of
1387          * targets on the adapter, after that we will switch to the real
1388          * allocated struct.
1389          */
1390         adapter = &adapter_temp;
1391         memset(adapter, 0, sizeof(*adapter));
1392         adapter->dev  = pdev;
1393         adapter->rev = pdev->revision;
1394
1395         if (pci_request_regions(pdev, "vmw_pvscsi")) {
1396                 printk(KERN_ERR "vmw_pvscsi: pci memory selection failed\n");
1397                 goto out_disable_device;
1398         }
1399
1400         for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
1401                 if ((pci_resource_flags(pdev, i) & PCI_BASE_ADDRESS_SPACE_IO))
1402                         continue;
1403
1404                 if (pci_resource_len(pdev, i) < PVSCSI_MEM_SPACE_SIZE)
1405                         continue;
1406
1407                 break;
1408         }
1409
1410         if (i == DEVICE_COUNT_RESOURCE) {
1411                 printk(KERN_ERR
1412                        "vmw_pvscsi: adapter has no suitable MMIO region\n");
1413                 goto out_release_resources_and_disable;
1414         }
1415
1416         adapter->mmioBase = pci_iomap(pdev, i, PVSCSI_MEM_SPACE_SIZE);
1417
1418         if (!adapter->mmioBase) {
1419                 printk(KERN_ERR
1420                        "vmw_pvscsi: can't iomap for BAR %d memsize %lu\n",
1421                        i, PVSCSI_MEM_SPACE_SIZE);
1422                 goto out_release_resources_and_disable;
1423         }
1424
1425         pci_set_master(pdev);
1426
1427         /*
1428          * Ask the device for max number of targets before deciding the
1429          * default pvscsi_ring_pages value.
1430          */
1431         max_id = pvscsi_get_max_targets(adapter);
1432         printk(KERN_INFO "vmw_pvscsi: max_id: %u\n", max_id);
1433
1434         if (pvscsi_ring_pages == 0)
1435                 /*
1436                  * Set the right default value. Up to 16 it is 8, above it is
1437                  * max.
1438                  */
1439                 pvscsi_ring_pages = (max_id > 16) ?
1440                         PVSCSI_SETUP_RINGS_MAX_NUM_PAGES :
1441                         PVSCSI_DEFAULT_NUM_PAGES_PER_RING;
1442         printk(KERN_INFO
1443                "vmw_pvscsi: setting ring_pages to %d\n",
1444                pvscsi_ring_pages);
1445
1446         pvscsi_template.can_queue =
1447                 min(PVSCSI_MAX_NUM_PAGES_REQ_RING, pvscsi_ring_pages) *
1448                 PVSCSI_MAX_NUM_REQ_ENTRIES_PER_PAGE;
1449         pvscsi_template.cmd_per_lun =
1450                 min(pvscsi_template.can_queue, pvscsi_cmd_per_lun);
1451         host = scsi_host_alloc(&pvscsi_template, sizeof(struct pvscsi_adapter));
1452         if (!host) {
1453                 printk(KERN_ERR "vmw_pvscsi: failed to allocate host\n");
1454                 goto out_release_resources_and_disable;
1455         }
1456
1457         /*
1458          * Let's use the real pvscsi_adapter struct here onwards.
1459          */
1460         adapter = shost_priv(host);
1461         memset(adapter, 0, sizeof(*adapter));
1462         adapter->dev  = pdev;
1463         adapter->host = host;
1464         /*
1465          * Copy back what we already have to the allocated adapter struct.
1466          */
1467         adapter->rev = adapter_temp.rev;
1468         adapter->mmioBase = adapter_temp.mmioBase;
1469
1470         spin_lock_init(&adapter->hw_lock);
1471         host->max_channel = 0;
1472         host->max_lun     = 1;
1473         host->max_cmd_len = 16;
1474         host->max_id      = max_id;
1475
1476         pci_set_drvdata(pdev, host);
1477
1478         ll_adapter_reset(adapter);
1479
1480         adapter->use_msg = pvscsi_setup_msg_workqueue(adapter);
1481
1482         error = pvscsi_allocate_rings(adapter);
1483         if (error) {
1484                 printk(KERN_ERR "vmw_pvscsi: unable to allocate ring memory\n");
1485                 goto out_release_resources;
1486         }
1487
1488         /*
1489          * From this point on we should reset the adapter if anything goes
1490          * wrong.
1491          */
1492         pvscsi_setup_all_rings(adapter);
1493
1494         adapter->cmd_map = kcalloc(adapter->req_depth,
1495                                    sizeof(struct pvscsi_ctx), GFP_KERNEL);
1496         if (!adapter->cmd_map) {
1497                 printk(KERN_ERR "vmw_pvscsi: failed to allocate memory.\n");
1498                 error = -ENOMEM;
1499                 goto out_reset_adapter;
1500         }
1501
1502         INIT_LIST_HEAD(&adapter->cmd_pool);
1503         for (i = 0; i < adapter->req_depth; i++) {
1504                 struct pvscsi_ctx *ctx = adapter->cmd_map + i;
1505                 list_add(&ctx->list, &adapter->cmd_pool);
1506         }
1507
1508         error = pvscsi_allocate_sg(adapter);
1509         if (error) {
1510                 printk(KERN_ERR "vmw_pvscsi: unable to allocate s/g table\n");
1511                 goto out_reset_adapter;
1512         }
1513
1514         if (!pvscsi_disable_msix &&
1515             pvscsi_setup_msix(adapter, &adapter->irq) == 0) {
1516                 printk(KERN_INFO "vmw_pvscsi: using MSI-X\n");
1517                 adapter->use_msix = 1;
1518         } else if (!pvscsi_disable_msi && pci_enable_msi(pdev) == 0) {
1519                 printk(KERN_INFO "vmw_pvscsi: using MSI\n");
1520                 adapter->use_msi = 1;
1521                 adapter->irq = pdev->irq;
1522         } else {
1523                 printk(KERN_INFO "vmw_pvscsi: using INTx\n");
1524                 adapter->irq = pdev->irq;
1525                 flags = IRQF_SHARED;
1526         }
1527
1528         adapter->use_req_threshold = pvscsi_setup_req_threshold(adapter, true);
1529         printk(KERN_DEBUG "vmw_pvscsi: driver-based request coalescing %sabled\n",
1530                adapter->use_req_threshold ? "en" : "dis");
1531
1532         error = request_irq(adapter->irq, pvscsi_isr, flags,
1533                             "vmw_pvscsi", adapter);
1534         if (error) {
1535                 printk(KERN_ERR
1536                        "vmw_pvscsi: unable to request IRQ: %d\n", error);
1537                 adapter->irq = 0;
1538                 goto out_reset_adapter;
1539         }
1540
1541         error = scsi_add_host(host, &pdev->dev);
1542         if (error) {
1543                 printk(KERN_ERR
1544                        "vmw_pvscsi: scsi_add_host failed: %d\n", error);
1545                 goto out_reset_adapter;
1546         }
1547
1548         dev_info(&pdev->dev, "VMware PVSCSI rev %d host #%u\n",
1549                  adapter->rev, host->host_no);
1550
1551         pvscsi_unmask_intr(adapter);
1552
1553         scsi_scan_host(host);
1554
1555         return 0;
1556
1557 out_reset_adapter:
1558         ll_adapter_reset(adapter);
1559 out_release_resources:
1560         pvscsi_release_resources(adapter);
1561         scsi_host_put(host);
1562 out_disable_device:
1563         pci_disable_device(pdev);
1564
1565         return error;
1566
1567 out_release_resources_and_disable:
1568         pvscsi_release_resources(adapter);
1569         goto out_disable_device;
1570 }
1571
1572 static void __pvscsi_shutdown(struct pvscsi_adapter *adapter)
1573 {
1574         pvscsi_mask_intr(adapter);
1575
1576         if (adapter->workqueue)
1577                 flush_workqueue(adapter->workqueue);
1578
1579         pvscsi_shutdown_intr(adapter);
1580
1581         pvscsi_process_request_ring(adapter);
1582         pvscsi_process_completion_ring(adapter);
1583         ll_adapter_reset(adapter);
1584 }
1585
1586 static void pvscsi_shutdown(struct pci_dev *dev)
1587 {
1588         struct Scsi_Host *host = pci_get_drvdata(dev);
1589         struct pvscsi_adapter *adapter = shost_priv(host);
1590
1591         __pvscsi_shutdown(adapter);
1592 }
1593
1594 static void pvscsi_remove(struct pci_dev *pdev)
1595 {
1596         struct Scsi_Host *host = pci_get_drvdata(pdev);
1597         struct pvscsi_adapter *adapter = shost_priv(host);
1598
1599         scsi_remove_host(host);
1600
1601         __pvscsi_shutdown(adapter);
1602         pvscsi_release_resources(adapter);
1603
1604         scsi_host_put(host);
1605
1606         pci_disable_device(pdev);
1607 }
1608
1609 static struct pci_driver pvscsi_pci_driver = {
1610         .name           = "vmw_pvscsi",
1611         .id_table       = pvscsi_pci_tbl,
1612         .probe          = pvscsi_probe,
1613         .remove         = pvscsi_remove,
1614         .shutdown       = pvscsi_shutdown,
1615 };
1616
1617 static int __init pvscsi_init(void)
1618 {
1619         pr_info("%s - version %s\n",
1620                 PVSCSI_LINUX_DRIVER_DESC, PVSCSI_DRIVER_VERSION_STRING);
1621         return pci_register_driver(&pvscsi_pci_driver);
1622 }
1623
1624 static void __exit pvscsi_exit(void)
1625 {
1626         pci_unregister_driver(&pvscsi_pci_driver);
1627 }
1628
1629 module_init(pvscsi_init);
1630 module_exit(pvscsi_exit);