drivers/scsi/ibmvscsi/ibmvscsi.c

   1 /* ------------------------------------------------------------
   2  * ibmvscsi.c
   3  * (C) Copyright IBM Corporation 1994, 2004
   4  * Authors: Colin DeVilbiss (devilbis@us.ibm.com)
   5  *          Santiago Leon (santil@us.ibm.com)
   6  *          Dave Boutcher (sleddog@us.ibm.com)
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
  21  * USA
  22  *
  23  * ------------------------------------------------------------
  24  * Emulation of a SCSI host adapter for Virtual I/O devices
  25  *
  26  * This driver supports the SCSI adapter implemented by the IBM
  27  * Power5 firmware.  That SCSI adapter is not a physical adapter,
  28  * but allows Linux SCSI peripheral drivers to directly
  29  * access devices in another logical partition on the physical system.
  30  *
  31  * The virtual adapter(s) are present in the open firmware device
  32  * tree just like real adapters.
  33  *
  34  * One of the capabilities provided on these systems is the ability
  35  * to DMA between partitions.  The architecture states that for VSCSI,
  36  * the server side is allowed to DMA to and from the client.  The client
  37  * is never trusted to DMA to or from the server directly.
  38  *
  39  * Messages are sent between partitions on a "Command/Response Queue"
  40  * (CRQ), which is just a buffer of 16 byte entries in the receiver's
  41  * Senders cannot access the buffer directly, but send messages by
  42  * making a hypervisor call and passing in the 16 bytes.  The hypervisor
  43  * puts the message in the next 16 byte space in round-robbin fashion,
  44  * turns on the high order bit of the message (the valid bit), and
  45  * generates an interrupt to the receiver (if interrupts are turned on.)
  46  * The receiver just turns off the valid bit when they have copied out
  47  * the message.
  48  *
  49  * The VSCSI client builds a SCSI Remote Protocol (SRP) Information Unit
  50  * (IU) (as defined in the T10 standard available at www.t10.org), gets
  51  * a DMA address for the message, and sends it to the server as the
  52  * payload of a CRQ message.  The server DMAs the SRP IU and processes it,
  53  * including doing any additional data transfers.  When it is done, it
  54  * DMAs the SRP response back to the same address as the request came from,
  55  * and sends a CRQ message back to inform the client that the request has
  56  * completed.
  57  *
  58  * Note that some of the underlying infrastructure is different between
  59  * machines conforming to the "RS/6000 Platform Architecture" (RPA) and
  60  * the older iSeries hypervisor models.  To support both, some low level
  61  * routines have been broken out into rpa_vscsi.c and iseries_vscsi.c.
  62  * The Makefile should pick one, not two, not zero, of these.
  63  *
  64  * TODO: This is currently pretty tied to the IBM i/pSeries hypervisor
  65  * interfaces.  It would be really nice to abstract this above an RDMA
  66  * layer.
  67  */
  68
  69 #include <linux/module.h>
  70 #include <linux/moduleparam.h>
  71 #include <linux/dma-mapping.h>
  72 #include <linux/delay.h>
  73 #include <asm/vio.h>
  74 #include <scsi/scsi.h>
  75 #include <scsi/scsi_cmnd.h>
  76 #include <scsi/scsi_host.h>
  77 #include <scsi/scsi_device.h>
  78 #include "ibmvscsi.h"
  79
  80 /* The values below are somewhat arbitrary default values, but
  81  * OS/400 will use 3 busses (disks, CDs, tapes, I think.)
  82  * Note that there are 3 bits of channel value, 6 bits of id, and
  83  * 5 bits of LUN.
  84  */
  85 static int max_id = 64;
  86 static int max_channel = 3;
  87 static int init_timeout = 5;
  88 static int max_requests = 50;
  89
  90 #define IBMVSCSI_VERSION "1.5.8"
  91
  92 MODULE_DESCRIPTION("IBM Virtual SCSI");
  93 MODULE_AUTHOR("Dave Boutcher");
  94 MODULE_LICENSE("GPL");
  95 MODULE_VERSION(IBMVSCSI_VERSION);
  96
  97 module_param_named(max_id, max_id, int, S_IRUGO | S_IWUSR);
  98 MODULE_PARM_DESC(max_id, "Largest ID value for each channel");
  99 module_param_named(max_channel, max_channel, int, S_IRUGO | S_IWUSR);
 100 MODULE_PARM_DESC(max_channel, "Largest channel value");
 101 module_param_named(init_timeout, init_timeout, int, S_IRUGO | S_IWUSR);
 102 MODULE_PARM_DESC(init_timeout, "Initialization timeout in seconds");
 103 module_param_named(max_requests, max_requests, int, S_IRUGO | S_IWUSR);
 104 MODULE_PARM_DESC(max_requests, "Maximum requests for this adapter");
 105
 106 /* ------------------------------------------------------------
 107  * Routines for the event pool and event structs
 108  */
 109 /**
 110  * initialize_event_pool: - Allocates and initializes the event pool for a host
 111  * @pool:       event_pool to be initialized
 112  * @size:       Number of events in pool
 113  * @hostdata:   ibmvscsi_host_data who owns the event pool
 114  *
 115  * Returns zero on success.
 116 */
 117 static int initialize_event_pool(struct event_pool *pool,
 118                                  int size, struct ibmvscsi_host_data *hostdata)
 119 {
 120         int i;
 121
 122         pool->size = size;
 123         pool->next = 0;
 124         pool->events = kcalloc(pool->size, sizeof(*pool->events), GFP_KERNEL);
 125         if (!pool->events)
 126                 return -ENOMEM;
 127
 128         pool->iu_storage =
 129             dma_alloc_coherent(hostdata->dev,
 130                                pool->size * sizeof(*pool->iu_storage),
 131                                &pool->iu_token, 0);
 132         if (!pool->iu_storage) {
 133                 kfree(pool->events);
 134                 return -ENOMEM;
 135         }
 136
 137         for (i = 0; i < pool->size; ++i) {
 138                 struct srp_event_struct *evt = &pool->events[i];
 139                 memset(&evt->crq, 0x00, sizeof(evt->crq));
 140                 atomic_set(&evt->free, 1);
 141                 evt->crq.valid = 0x80;
 142                 evt->crq.IU_length = sizeof(*evt->xfer_iu);
 143                 evt->crq.IU_data_ptr = pool->iu_token +
 144                         sizeof(*evt->xfer_iu) * i;
 145                 evt->xfer_iu = pool->iu_storage + i;
 146                 evt->hostdata = hostdata;
 147                 evt->ext_list = NULL;
 148                 evt->ext_list_token = 0;
 149         }
 150
 151         return 0;
 152 }
 153
 154 /**
 155  * release_event_pool: - Frees memory of an event pool of a host
 156  * @pool:       event_pool to be released
 157  * @hostdata:   ibmvscsi_host_data who owns the even pool
 158  *
 159  * Returns zero on success.
 160 */
 161 static void release_event_pool(struct event_pool *pool,
 162                                struct ibmvscsi_host_data *hostdata)
 163 {
 164         int i, in_use = 0;
 165         for (i = 0; i < pool->size; ++i) {
 166                 if (atomic_read(&pool->events[i].free) != 1)
 167                         ++in_use;
 168                 if (pool->events[i].ext_list) {
 169                         dma_free_coherent(hostdata->dev,
 170                                   SG_ALL * sizeof(struct srp_direct_buf),
 171                                   pool->events[i].ext_list,
 172                                   pool->events[i].ext_list_token);
 173                 }
 174         }
 175         if (in_use)
 176                 printk(KERN_WARNING
 177                        "ibmvscsi: releasing event pool with %d "
 178                        "events still in use?\n", in_use);
 179         kfree(pool->events);
 180         dma_free_coherent(hostdata->dev,
 181                           pool->size * sizeof(*pool->iu_storage),
 182                           pool->iu_storage, pool->iu_token);
 183 }
 184
 185 /**
 186  * valid_event_struct: - Determines if event is valid.
 187  * @pool:       event_pool that contains the event
 188  * @evt:        srp_event_struct to be checked for validity
 189  *
 190  * Returns zero if event is invalid, one otherwise.
 191 */
 192 static int valid_event_struct(struct event_pool *pool,
 193                                 struct srp_event_struct *evt)
 194 {
 195         int index = evt - pool->events;
 196         if (index < 0 || index >= pool->size)   /* outside of bounds */
 197                 return 0;
 198         if (evt != pool->events + index)        /* unaligned */
 199                 return 0;
 200         return 1;
 201 }
 202
 203 /**
 204  * ibmvscsi_free-event_struct: - Changes status of event to "free"
 205  * @pool:       event_pool that contains the event
 206  * @evt:        srp_event_struct to be modified
 207  *
 208 */
 209 static void free_event_struct(struct event_pool *pool,
 210                                        struct srp_event_struct *evt)
 211 {
 212         if (!valid_event_struct(pool, evt)) {
 213                 printk(KERN_ERR
 214                        "ibmvscsi: Freeing invalid event_struct %p "
 215                        "(not in pool %p)\n", evt, pool->events);
 216                 return;
 217         }
 218         if (atomic_inc_return(&evt->free) != 1) {
 219                 printk(KERN_ERR
 220                        "ibmvscsi: Freeing event_struct %p "
 221                        "which is not in use!\n", evt);
 222                 return;
 223         }
 224 }
 225
 226 /**
 227  * get_evt_struct: - Gets the next free event in pool
 228  * @pool:       event_pool that contains the events to be searched
 229  *
 230  * Returns the next event in "free" state, and NULL if none are free.
 231  * Note that no synchronization is done here, we assume the host_lock
 232  * will syncrhonze things.
 233 */
 234 static struct srp_event_struct *get_event_struct(struct event_pool *pool)
 235 {
 236         int i;
 237         int poolsize = pool->size;
 238         int offset = pool->next;
 239
 240         for (i = 0; i < poolsize; i++) {
 241                 offset = (offset + 1) % poolsize;
 242                 if (!atomic_dec_if_positive(&pool->events[offset].free)) {
 243                         pool->next = offset;
 244                         return &pool->events[offset];
 245                 }
 246         }
 247
 248         printk(KERN_ERR "ibmvscsi: found no event struct in pool!\n");
 249         return NULL;
 250 }
 251
 252 /**
 253  * init_event_struct: Initialize fields in an event struct that are always
 254  *                    required.
 255  * @evt:        The event
 256  * @done:       Routine to call when the event is responded to
 257  * @format:     SRP or MAD format
 258  * @timeout:    timeout value set in the CRQ
 259  */
 260 static void init_event_struct(struct srp_event_struct *evt_struct,
 261                               void (*done) (struct srp_event_struct *),
 262                               u8 format,
 263                               int timeout)
 264 {
 265         evt_struct->cmnd = NULL;
 266         evt_struct->cmnd_done = NULL;
 267         evt_struct->sync_srp = NULL;
 268         evt_struct->crq.format = format;
 269         evt_struct->crq.timeout = timeout;
 270         evt_struct->done = done;
 271 }
 272
 273 /* ------------------------------------------------------------
 274  * Routines for receiving SCSI responses from the hosting partition
 275  */
 276
 277 /**
 278  * set_srp_direction: Set the fields in the srp related to data
 279  *     direction and number of buffers based on the direction in
 280  *     the scsi_cmnd and the number of buffers
 281  */
 282 static void set_srp_direction(struct scsi_cmnd *cmd,
 283                               struct srp_cmd *srp_cmd,
 284                               int numbuf)
 285 {
 286         u8 fmt;
 287
 288         if (numbuf == 0)
 289                 return;
 290
 291         if (numbuf == 1)
 292                 fmt = SRP_DATA_DESC_DIRECT;
 293         else {
 294                 fmt = SRP_DATA_DESC_INDIRECT;
 295                 numbuf = min(numbuf, MAX_INDIRECT_BUFS);
 296
 297                 if (cmd->sc_data_direction == DMA_TO_DEVICE)
 298                         srp_cmd->data_out_desc_cnt = numbuf;
 299                 else
 300                         srp_cmd->data_in_desc_cnt = numbuf;
 301         }
 302
 303         if (cmd->sc_data_direction == DMA_TO_DEVICE)
 304                 srp_cmd->buf_fmt = fmt << 4;
 305         else
 306                 srp_cmd->buf_fmt = fmt;
 307 }
 308
 309 static void unmap_sg_list(int num_entries,
 310                 struct device *dev,
 311                 struct srp_direct_buf *md)
 312 {
 313         int i;
 314
 315         for (i = 0; i < num_entries; ++i)
 316                 dma_unmap_single(dev, md[i].va, md[i].len, DMA_BIDIRECTIONAL);
 317 }
 318
 319 /**
 320  * unmap_cmd_data: - Unmap data pointed in srp_cmd based on the format
 321  * @cmd:        srp_cmd whose additional_data member will be unmapped
 322  * @dev:        device for which the memory is mapped
 323  *
 324 */
 325 static void unmap_cmd_data(struct srp_cmd *cmd,
 326                            struct srp_event_struct *evt_struct,
 327                            struct device *dev)
 328 {
 329         u8 out_fmt, in_fmt;
 330
 331         out_fmt = cmd->buf_fmt >> 4;
 332         in_fmt = cmd->buf_fmt & ((1U << 4) - 1);
 333
 334         if (out_fmt == SRP_NO_DATA_DESC && in_fmt == SRP_NO_DATA_DESC)
 335                 return;
 336         else if (out_fmt == SRP_DATA_DESC_DIRECT ||
 337                  in_fmt == SRP_DATA_DESC_DIRECT) {
 338                 struct srp_direct_buf *data =
 339                         (struct srp_direct_buf *) cmd->add_data;
 340                 dma_unmap_single(dev, data->va, data->len, DMA_BIDIRECTIONAL);
 341         } else {
 342                 struct srp_indirect_buf *indirect =
 343                         (struct srp_indirect_buf *) cmd->add_data;
 344                 int num_mapped = indirect->table_desc.len /
 345                         sizeof(struct srp_direct_buf);
 346
 347                 if (num_mapped <= MAX_INDIRECT_BUFS) {
 348                         unmap_sg_list(num_mapped, dev, &indirect->desc_list[0]);
 349                         return;
 350                 }
 351
 352                 unmap_sg_list(num_mapped, dev, evt_struct->ext_list);
 353         }
 354 }
 355
 356 static int map_sg_list(int num_entries,
 357                        struct scatterlist *sg,
 358                        struct srp_direct_buf *md)
 359 {
 360         int i;
 361         u64 total_length = 0;
 362
 363         for (i = 0; i < num_entries; ++i) {
 364                 struct srp_direct_buf *descr = md + i;
 365                 struct scatterlist *sg_entry = &sg[i];
 366                 descr->va = sg_dma_address(sg_entry);
 367                 descr->len = sg_dma_len(sg_entry);
 368                 descr->key = 0;
 369                 total_length += sg_dma_len(sg_entry);
 370         }
 371         return total_length;
 372 }
 373
 374 /**
 375  * map_sg_data: - Maps dma for a scatterlist and initializes decriptor fields
 376  * @cmd:        Scsi_Cmnd with the scatterlist
 377  * @srp_cmd:    srp_cmd that contains the memory descriptor
 378  * @dev:        device for which to map dma memory
 379  *
 380  * Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
 381  * Returns 1 on success.
 382 */
 383 static int map_sg_data(struct scsi_cmnd *cmd,
 384                        struct srp_event_struct *evt_struct,
 385                        struct srp_cmd *srp_cmd, struct device *dev)
 386 {
 387
 388         int sg_mapped;
 389         u64 total_length = 0;
 390         struct scatterlist *sg = cmd->request_buffer;
 391         struct srp_direct_buf *data =
 392                 (struct srp_direct_buf *) srp_cmd->add_data;
 393         struct srp_indirect_buf *indirect =
 394                 (struct srp_indirect_buf *) data;
 395
 396         sg_mapped = dma_map_sg(dev, sg, cmd->use_sg, DMA_BIDIRECTIONAL);
 397
 398         if (sg_mapped == 0)
 399                 return 0;
 400
 401         set_srp_direction(cmd, srp_cmd, sg_mapped);
 402
 403         /* special case; we can use a single direct descriptor */
 404         if (sg_mapped == 1) {
 405                 data->va = sg_dma_address(&sg[0]);
 406                 data->len = sg_dma_len(&sg[0]);
 407                 data->key = 0;
 408                 return 1;
 409         }
 410
 411         if (sg_mapped > SG_ALL) {
 412                 printk(KERN_ERR
 413                        "ibmvscsi: More than %d mapped sg entries, got %d\n",
 414                        SG_ALL, sg_mapped);
 415                 return 0;
 416         }
 417
 418         indirect->table_desc.va = 0;
 419         indirect->table_desc.len = sg_mapped * sizeof(struct srp_direct_buf);
 420         indirect->table_desc.key = 0;
 421
 422         if (sg_mapped <= MAX_INDIRECT_BUFS) {
 423                 total_length = map_sg_list(sg_mapped, sg,
 424                                            &indirect->desc_list[0]);
 425                 indirect->len = total_length;
 426                 return 1;
 427         }
 428
 429         /* get indirect table */
 430         if (!evt_struct->ext_list) {
 431                 evt_struct->ext_list = (struct srp_direct_buf *)
 432                         dma_alloc_coherent(dev,
 433                                            SG_ALL * sizeof(struct srp_direct_buf),
 434                                            &evt_struct->ext_list_token, 0);
 435                 if (!evt_struct->ext_list) {
 436                         printk(KERN_ERR
 437                                "ibmvscsi: Can't allocate memory for indirect table\n");
 438                         return 0;
 439
 440                 }
 441         }
 442
 443         total_length = map_sg_list(sg_mapped, sg, evt_struct->ext_list);
 444
 445         indirect->len = total_length;
 446         indirect->table_desc.va = evt_struct->ext_list_token;
 447         indirect->table_desc.len = sg_mapped * sizeof(indirect->desc_list[0]);
 448         memcpy(indirect->desc_list, evt_struct->ext_list,
 449                MAX_INDIRECT_BUFS * sizeof(struct srp_direct_buf));
 450
 451         return 1;
 452 }
 453
 454 /**
 455  * map_single_data: - Maps memory and initializes memory decriptor fields
 456  * @cmd:        struct scsi_cmnd with the memory to be mapped
 457  * @srp_cmd:    srp_cmd that contains the memory descriptor
 458  * @dev:        device for which to map dma memory
 459  *
 460  * Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
 461  * Returns 1 on success.
 462 */
 463 static int map_single_data(struct scsi_cmnd *cmd,
 464                            struct srp_cmd *srp_cmd, struct device *dev)
 465 {
 466         struct srp_direct_buf *data =
 467                 (struct srp_direct_buf *) srp_cmd->add_data;
 468
 469         data->va =
 470                 dma_map_single(dev, cmd->request_buffer,
 471                                cmd->request_bufflen,
 472                                DMA_BIDIRECTIONAL);
 473         if (dma_mapping_error(data->va)) {
 474                 printk(KERN_ERR
 475                        "ibmvscsi: Unable to map request_buffer for command!\n");
 476                 return 0;
 477         }
 478         data->len = cmd->request_bufflen;
 479         data->key = 0;
 480
 481         set_srp_direction(cmd, srp_cmd, 1);
 482
 483         return 1;
 484 }
 485
 486 /**
 487  * map_data_for_srp_cmd: - Calls functions to map data for srp cmds
 488  * @cmd:        struct scsi_cmnd with the memory to be mapped
 489  * @srp_cmd:    srp_cmd that contains the memory descriptor
 490  * @dev:        dma device for which to map dma memory
 491  *
 492  * Called by scsi_cmd_to_srp_cmd() when converting scsi cmds to srp cmds
 493  * Returns 1 on success.
 494 */
 495 static int map_data_for_srp_cmd(struct scsi_cmnd *cmd,
 496                                 struct srp_event_struct *evt_struct,
 497                                 struct srp_cmd *srp_cmd, struct device *dev)
 498 {
 499         switch (cmd->sc_data_direction) {
 500         case DMA_FROM_DEVICE:
 501         case DMA_TO_DEVICE:
 502                 break;
 503         case DMA_NONE:
 504                 return 1;
 505         case DMA_BIDIRECTIONAL:
 506                 printk(KERN_ERR
 507                        "ibmvscsi: Can't map DMA_BIDIRECTIONAL to read/write\n");
 508                 return 0;
 509         default:
 510                 printk(KERN_ERR
 511                        "ibmvscsi: Unknown data direction 0x%02x; can't map!\n",
 512                        cmd->sc_data_direction);
 513                 return 0;
 514         }
 515
 516         if (!cmd->request_buffer)
 517                 return 1;
 518         if (cmd->use_sg)
 519                 return map_sg_data(cmd, evt_struct, srp_cmd, dev);
 520         return map_single_data(cmd, srp_cmd, dev);
 521 }
 522
 523 /* ------------------------------------------------------------
 524  * Routines for sending and receiving SRPs
 525  */
 526 /**
 527  * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
 528  * @evt_struct: evt_struct to be sent
 529  * @hostdata:   ibmvscsi_host_data of host
 530  *
 531  * Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
 532  * Note that this routine assumes that host_lock is held for synchronization
 533 */
 534 static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
 535                                    struct ibmvscsi_host_data *hostdata)
 536 {
 537         u64 *crq_as_u64 = (u64 *) &evt_struct->crq;
 538         int request_status;
 539         int rc;
 540
 541         /* If we have exhausted our request limit, just fail this request.
 542          * Note that there are rare cases involving driver generated requests
 543          * (such as task management requests) that the mid layer may think we
 544          * can handle more requests (can_queue) when we actually can't
 545          */
 546         if (evt_struct->crq.format == VIOSRP_SRP_FORMAT) {
 547                 request_status =
 548                         atomic_dec_if_positive(&hostdata->request_limit);
 549                 /* If request limit was -1 when we started, it is now even
 550                  * less than that
 551                  */
 552                 if (request_status < -1)
 553                         goto send_error;
 554                 /* Otherwise, if we have run out of requests */
 555                 else if (request_status < 0)
 556                         goto send_busy;
 557         }
 558
 559         /* Copy the IU into the transfer area */
 560         *evt_struct->xfer_iu = evt_struct->iu;
 561         evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
 562
 563         /* Add this to the sent list.  We need to do this
 564          * before we actually send
 565          * in case it comes back REALLY fast
 566          */
 567         list_add_tail(&evt_struct->list, &hostdata->sent);
 568
 569         if ((rc =
 570              ibmvscsi_send_crq(hostdata, crq_as_u64[0], crq_as_u64[1])) != 0) {
 571                 list_del(&evt_struct->list);
 572
 573                 printk(KERN_ERR "ibmvscsi: send error %d\n",
 574                        rc);
 575                 goto send_error;
 576         }
 577
 578         return 0;
 579
 580  send_busy:
 581         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 582
 583         free_event_struct(&hostdata->pool, evt_struct);
 584         return SCSI_MLQUEUE_HOST_BUSY;
 585
 586  send_error:
 587         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 588
 589         if (evt_struct->cmnd != NULL) {
 590                 evt_struct->cmnd->result = DID_ERROR << 16;
 591                 evt_struct->cmnd_done(evt_struct->cmnd);
 592         } else if (evt_struct->done)
 593                 evt_struct->done(evt_struct);
 594
 595         free_event_struct(&hostdata->pool, evt_struct);
 596         return 0;
 597 }
 598
 599 /**
 600  * handle_cmd_rsp: -  Handle responses from commands
 601  * @evt_struct: srp_event_struct to be handled
 602  *
 603  * Used as a callback by when sending scsi cmds.
 604  * Gets called by ibmvscsi_handle_crq()
 605 */
 606 static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
 607 {
 608         struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
 609         struct scsi_cmnd *cmnd = evt_struct->cmnd;
 610
 611         if (unlikely(rsp->opcode != SRP_RSP)) {
 612                 if (printk_ratelimit())
 613                         printk(KERN_WARNING
 614                                "ibmvscsi: bad SRP RSP type %d\n",
 615                                rsp->opcode);
 616         }
 617
 618         if (cmnd) {
 619                 cmnd->result = rsp->status;
 620                 if (((cmnd->result >> 1) & 0x1f) == CHECK_CONDITION)
 621                         memcpy(cmnd->sense_buffer,
 622                                rsp->data,
 623                                rsp->sense_data_len);
 624                 unmap_cmd_data(&evt_struct->iu.srp.cmd,
 625                                evt_struct,
 626                                evt_struct->hostdata->dev);
 627
 628                 if (rsp->flags & SRP_RSP_FLAG_DOOVER)
 629                         cmnd->resid = rsp->data_out_res_cnt;
 630                 else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
 631                         cmnd->resid = rsp->data_in_res_cnt;
 632         }
 633
 634         if (evt_struct->cmnd_done)
 635                 evt_struct->cmnd_done(cmnd);
 636 }
 637
 638 /**
 639  * lun_from_dev: - Returns the lun of the scsi device
 640  * @dev:        struct scsi_device
 641  *
 642 */
 643 static inline u16 lun_from_dev(struct scsi_device *dev)
 644 {
 645         return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
 646 }
 647
 648 /**
 649  * ibmvscsi_queue: - The queuecommand function of the scsi template
 650  * @cmd:        struct scsi_cmnd to be executed
 651  * @done:       Callback function to be called when cmd is completed
 652 */
 653 static int ibmvscsi_queuecommand(struct scsi_cmnd *cmnd,
 654                                  void (*done) (struct scsi_cmnd *))
 655 {
 656         struct srp_cmd *srp_cmd;
 657         struct srp_event_struct *evt_struct;
 658         struct srp_indirect_buf *indirect;
 659         struct ibmvscsi_host_data *hostdata =
 660                 (struct ibmvscsi_host_data *)&cmnd->device->host->hostdata;
 661         u16 lun = lun_from_dev(cmnd->device);
 662         u8 out_fmt, in_fmt;
 663
 664         evt_struct = get_event_struct(&hostdata->pool);
 665         if (!evt_struct)
 666                 return SCSI_MLQUEUE_HOST_BUSY;
 667
 668         /* Set up the actual SRP IU */
 669         srp_cmd = &evt_struct->iu.srp.cmd;
 670         memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
 671         srp_cmd->opcode = SRP_CMD;
 672         memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(cmnd->cmnd));
 673         srp_cmd->lun = ((u64) lun) << 48;
 674
 675         if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
 676                 printk(KERN_ERR "ibmvscsi: couldn't convert cmd to srp_cmd\n");
 677                 free_event_struct(&hostdata->pool, evt_struct);
 678                 return SCSI_MLQUEUE_HOST_BUSY;
 679         }
 680
 681         init_event_struct(evt_struct,
 682                           handle_cmd_rsp,
 683                           VIOSRP_SRP_FORMAT,
 684                           cmnd->timeout_per_command/HZ);
 685
 686         evt_struct->cmnd = cmnd;
 687         evt_struct->cmnd_done = done;
 688
 689         /* Fix up dma address of the buffer itself */
 690         indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
 691         out_fmt = srp_cmd->buf_fmt >> 4;
 692         in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
 693         if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
 694              out_fmt == SRP_DATA_DESC_INDIRECT) &&
 695             indirect->table_desc.va == 0) {
 696                 indirect->table_desc.va = evt_struct->crq.IU_data_ptr +
 697                         offsetof(struct srp_cmd, add_data) +
 698                         offsetof(struct srp_indirect_buf, desc_list);
 699         }
 700
 701         return ibmvscsi_send_srp_event(evt_struct, hostdata);
 702 }
 703
 704 /* ------------------------------------------------------------
 705  * Routines for driver initialization
 706  */
 707 /**
 708  * adapter_info_rsp: - Handle response to MAD adapter info request
 709  * @evt_struct: srp_event_struct with the response
 710  *
 711  * Used as a "done" callback by when sending adapter_info. Gets called
 712  * by ibmvscsi_handle_crq()
 713 */
 714 static void adapter_info_rsp(struct srp_event_struct *evt_struct)
 715 {
 716         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 717         dma_unmap_single(hostdata->dev,
 718                          evt_struct->iu.mad.adapter_info.buffer,
 719                          evt_struct->iu.mad.adapter_info.common.length,
 720                          DMA_BIDIRECTIONAL);
 721
 722         if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
 723                 printk("ibmvscsi: error %d getting adapter info\n",
 724                        evt_struct->xfer_iu->mad.adapter_info.common.status);
 725         } else {
 726                 printk("ibmvscsi: host srp version: %s, "
 727                        "host partition %s (%d), OS %d, max io %u\n",
 728                        hostdata->madapter_info.srp_version,
 729                        hostdata->madapter_info.partition_name,
 730                        hostdata->madapter_info.partition_number,
 731                        hostdata->madapter_info.os_type,
 732                        hostdata->madapter_info.port_max_txu[0]);
 733
 734                 if (hostdata->madapter_info.port_max_txu[0])
 735                         hostdata->host->max_sectors =
 736                                 hostdata->madapter_info.port_max_txu[0] >> 9;
 737
 738                 if (hostdata->madapter_info.os_type == 3 &&
 739                     strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
 740                         printk("ibmvscsi: host (Ver. %s) doesn't support large"
 741                                "transfers\n",
 742                                hostdata->madapter_info.srp_version);
 743                         printk("ibmvscsi: limiting scatterlists to %d\n",
 744                                MAX_INDIRECT_BUFS);
 745                         hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
 746                 }
 747         }
 748 }
 749
 750 /**
 751  * send_mad_adapter_info: - Sends the mad adapter info request
 752  *      and stores the result so it can be retrieved with
 753  *      sysfs.  We COULD consider causing a failure if the
 754  *      returned SRP version doesn't match ours.
 755  * @hostdata:   ibmvscsi_host_data of host
 756  *
 757  * Returns zero if successful.
 758 */
 759 static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
 760 {
 761         struct viosrp_adapter_info *req;
 762         struct srp_event_struct *evt_struct;
 763         dma_addr_t addr;
 764
 765         evt_struct = get_event_struct(&hostdata->pool);
 766         if (!evt_struct) {
 767                 printk(KERN_ERR "ibmvscsi: couldn't allocate an event "
 768                        "for ADAPTER_INFO_REQ!\n");
 769                 return;
 770         }
 771
 772         init_event_struct(evt_struct,
 773                           adapter_info_rsp,
 774                           VIOSRP_MAD_FORMAT,
 775                           init_timeout * HZ);
 776
 777         req = &evt_struct->iu.mad.adapter_info;
 778         memset(req, 0x00, sizeof(*req));
 779
 780         req->common.type = VIOSRP_ADAPTER_INFO_TYPE;
 781         req->common.length = sizeof(hostdata->madapter_info);
 782         req->buffer = addr = dma_map_single(hostdata->dev,
 783                                             &hostdata->madapter_info,
 784                                             sizeof(hostdata->madapter_info),
 785                                             DMA_BIDIRECTIONAL);
 786
 787         if (dma_mapping_error(req->buffer)) {
 788                 printk(KERN_ERR
 789                        "ibmvscsi: Unable to map request_buffer "
 790                        "for adapter_info!\n");
 791                 free_event_struct(&hostdata->pool, evt_struct);
 792                 return;
 793         }
 794
 795         if (ibmvscsi_send_srp_event(evt_struct, hostdata)) {
 796                 printk(KERN_ERR "ibmvscsi: couldn't send ADAPTER_INFO_REQ!\n");
 797                 dma_unmap_single(hostdata->dev,
 798                                  addr,
 799                                  sizeof(hostdata->madapter_info),
 800                                  DMA_BIDIRECTIONAL);
 801         }
 802 };
 803
 804 /**
 805  * login_rsp: - Handle response to SRP login request
 806  * @evt_struct: srp_event_struct with the response
 807  *
 808  * Used as a "done" callback by when sending srp_login. Gets called
 809  * by ibmvscsi_handle_crq()
 810 */
 811 static void login_rsp(struct srp_event_struct *evt_struct)
 812 {
 813         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 814         switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
 815         case SRP_LOGIN_RSP:     /* it worked! */
 816                 break;
 817         case SRP_LOGIN_REJ:     /* refused! */
 818                 printk(KERN_INFO "ibmvscsi: SRP_LOGIN_REJ reason %u\n",
 819                        evt_struct->xfer_iu->srp.login_rej.reason);
 820                 /* Login failed.  */
 821                 atomic_set(&hostdata->request_limit, -1);
 822                 return;
 823         default:
 824                 printk(KERN_ERR
 825                        "ibmvscsi: Invalid login response typecode 0x%02x!\n",
 826                        evt_struct->xfer_iu->srp.login_rsp.opcode);
 827                 /* Login failed.  */
 828                 atomic_set(&hostdata->request_limit, -1);
 829                 return;
 830         }
 831
 832         printk(KERN_INFO "ibmvscsi: SRP_LOGIN succeeded\n");
 833
 834         if (evt_struct->xfer_iu->srp.login_rsp.req_lim_delta >
 835             (max_requests - 2))
 836                 evt_struct->xfer_iu->srp.login_rsp.req_lim_delta =
 837                     max_requests - 2;
 838
 839         /* Now we know what the real request-limit is */
 840         atomic_set(&hostdata->request_limit,
 841                    evt_struct->xfer_iu->srp.login_rsp.req_lim_delta);
 842
 843         hostdata->host->can_queue =
 844             evt_struct->xfer_iu->srp.login_rsp.req_lim_delta - 2;
 845
 846         if (hostdata->host->can_queue < 1) {
 847                 printk(KERN_ERR "ibmvscsi: Invalid request_limit_delta\n");
 848                 return;
 849         }
 850
 851         /* If we had any pending I/Os, kick them */
 852         scsi_unblock_requests(hostdata->host);
 853
 854         send_mad_adapter_info(hostdata);
 855         return;
 856 }
 857
 858 /**
 859  * send_srp_login: - Sends the srp login
 860  * @hostdata:   ibmvscsi_host_data of host
 861  *
 862  * Returns zero if successful.
 863 */
 864 static int send_srp_login(struct ibmvscsi_host_data *hostdata)
 865 {
 866         int rc;
 867         unsigned long flags;
 868         struct srp_login_req *login;
 869         struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
 870         if (!evt_struct) {
 871                 printk(KERN_ERR
 872                        "ibmvscsi: couldn't allocate an event for login req!\n");
 873                 return FAILED;
 874         }
 875
 876         init_event_struct(evt_struct,
 877                           login_rsp,
 878                           VIOSRP_SRP_FORMAT,
 879                           init_timeout * HZ);
 880
 881         login = &evt_struct->iu.srp.login_req;
 882         memset(login, 0x00, sizeof(struct srp_login_req));
 883         login->opcode = SRP_LOGIN_REQ;
 884         login->req_it_iu_len = sizeof(union srp_iu);
 885         login->req_buf_fmt = SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT;
 886
 887         spin_lock_irqsave(hostdata->host->host_lock, flags);
 888         /* Start out with a request limit of 1, since this is negotiated in
 889          * the login request we are just sending
 890          */
 891         atomic_set(&hostdata->request_limit, 1);
 892
 893         rc = ibmvscsi_send_srp_event(evt_struct, hostdata);
 894         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 895         printk("ibmvscsic: sent SRP login\n");
 896         return rc;
 897 };
 898
 899 /**
 900  * sync_completion: Signal that a synchronous command has completed
 901  * Note that after returning from this call, the evt_struct is freed.
 902  * the caller waiting on this completion shouldn't touch the evt_struct
 903  * again.
 904  */
 905 static void sync_completion(struct srp_event_struct *evt_struct)
 906 {
 907         /* copy the response back */
 908         if (evt_struct->sync_srp)
 909                 *evt_struct->sync_srp = *evt_struct->xfer_iu;
 910
 911         complete(&evt_struct->comp);
 912 }
 913
 914 /**
 915  * ibmvscsi_abort: Abort a command...from scsi host template
 916  * send this over to the server and wait synchronously for the response
 917  */
 918 static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
 919 {
 920         struct ibmvscsi_host_data *hostdata =
 921             (struct ibmvscsi_host_data *)cmd->device->host->hostdata;
 922         struct srp_tsk_mgmt *tsk_mgmt;
 923         struct srp_event_struct *evt;
 924         struct srp_event_struct *tmp_evt, *found_evt;
 925         union viosrp_iu srp_rsp;
 926         int rsp_rc;
 927         unsigned long flags;
 928         u16 lun = lun_from_dev(cmd->device);
 929
 930         /* First, find this command in our sent list so we can figure
 931          * out the correct tag
 932          */
 933         spin_lock_irqsave(hostdata->host->host_lock, flags);
 934         found_evt = NULL;
 935         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
 936                 if (tmp_evt->cmnd == cmd) {
 937                         found_evt = tmp_evt;
 938                         break;
 939                 }
 940         }
 941
 942         if (!found_evt) {
 943                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 944                 return FAILED;
 945         }
 946
 947         evt = get_event_struct(&hostdata->pool);
 948         if (evt == NULL) {
 949                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 950                 printk(KERN_ERR "ibmvscsi: failed to allocate abort event\n");
 951                 return FAILED;
 952         }
 953
 954         init_event_struct(evt,
 955                           sync_completion,
 956                           VIOSRP_SRP_FORMAT,
 957                           init_timeout * HZ);
 958
 959         tsk_mgmt = &evt->iu.srp.tsk_mgmt;
 960
 961         /* Set up an abort SRP command */
 962         memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
 963         tsk_mgmt->opcode = SRP_TSK_MGMT;
 964         tsk_mgmt->lun = ((u64) lun) << 48;
 965         tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
 966         tsk_mgmt->task_tag = (u64) found_evt;
 967
 968         printk(KERN_INFO "ibmvscsi: aborting command. lun 0x%lx, tag 0x%lx\n",
 969                tsk_mgmt->lun, tsk_mgmt->task_tag);
 970
 971         evt->sync_srp = &srp_rsp;
 972         init_completion(&evt->comp);
 973         rsp_rc = ibmvscsi_send_srp_event(evt, hostdata);
 974         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 975         if (rsp_rc != 0) {
 976                 printk(KERN_ERR "ibmvscsi: failed to send abort() event\n");
 977                 return FAILED;
 978         }
 979
 980         wait_for_completion(&evt->comp);
 981
 982         /* make sure we got a good response */
 983         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
 984                 if (printk_ratelimit())
 985                         printk(KERN_WARNING
 986                                "ibmvscsi: abort bad SRP RSP type %d\n",
 987                                srp_rsp.srp.rsp.opcode);
 988                 return FAILED;
 989         }
 990
 991         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
 992                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
 993         else
 994                 rsp_rc = srp_rsp.srp.rsp.status;
 995
 996         if (rsp_rc) {
 997                 if (printk_ratelimit())
 998                         printk(KERN_WARNING
 999                                "ibmvscsi: abort code %d for task tag 0x%lx\n",
1000                                rsp_rc,
1001                                tsk_mgmt->task_tag);
1002                 return FAILED;
1003         }
1004
1005         /* Because we dropped the spinlock above, it's possible
1006          * The event is no longer in our list.  Make sure it didn't
1007          * complete while we were aborting
1008          */
1009         spin_lock_irqsave(hostdata->host->host_lock, flags);
1010         found_evt = NULL;
1011         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1012                 if (tmp_evt->cmnd == cmd) {
1013                         found_evt = tmp_evt;
1014                         break;
1015                 }
1016         }
1017
1018         if (found_evt == NULL) {
1019                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1020                 printk(KERN_INFO
1021                        "ibmvscsi: aborted task tag 0x%lx completed\n",
1022                        tsk_mgmt->task_tag);
1023                 return SUCCESS;
1024         }
1025
1026         printk(KERN_INFO
1027                "ibmvscsi: successfully aborted task tag 0x%lx\n",
1028                tsk_mgmt->task_tag);
1029
1030         cmd->result = (DID_ABORT << 16);
1031         list_del(&found_evt->list);
1032         unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
1033                        found_evt->hostdata->dev);
1034         free_event_struct(&found_evt->hostdata->pool, found_evt);
1035         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1036         atomic_inc(&hostdata->request_limit);
1037         return SUCCESS;
1038 }
1039
1040 /**
1041  * ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host
1042  * template send this over to the server and wait synchronously for the
1043  * response
1044  */
1045 static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
1046 {
1047         struct ibmvscsi_host_data *hostdata =
1048             (struct ibmvscsi_host_data *)cmd->device->host->hostdata;
1049
1050         struct srp_tsk_mgmt *tsk_mgmt;
1051         struct srp_event_struct *evt;
1052         struct srp_event_struct *tmp_evt, *pos;
1053         union viosrp_iu srp_rsp;
1054         int rsp_rc;
1055         unsigned long flags;
1056         u16 lun = lun_from_dev(cmd->device);
1057
1058         spin_lock_irqsave(hostdata->host->host_lock, flags);
1059         evt = get_event_struct(&hostdata->pool);
1060         if (evt == NULL) {
1061                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1062                 printk(KERN_ERR "ibmvscsi: failed to allocate reset event\n");
1063                 return FAILED;
1064         }
1065
1066         init_event_struct(evt,
1067                           sync_completion,
1068                           VIOSRP_SRP_FORMAT,
1069                           init_timeout * HZ);
1070
1071         tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1072
1073         /* Set up a lun reset SRP command */
1074         memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1075         tsk_mgmt->opcode = SRP_TSK_MGMT;
1076         tsk_mgmt->lun = ((u64) lun) << 48;
1077         tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
1078
1079         printk(KERN_INFO "ibmvscsi: resetting device. lun 0x%lx\n",
1080                tsk_mgmt->lun);
1081
1082         evt->sync_srp = &srp_rsp;
1083         init_completion(&evt->comp);
1084         rsp_rc = ibmvscsi_send_srp_event(evt, hostdata);
1085         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1086         if (rsp_rc != 0) {
1087                 printk(KERN_ERR "ibmvscsi: failed to send reset event\n");
1088                 return FAILED;
1089         }
1090
1091         wait_for_completion(&evt->comp);
1092
1093         /* make sure we got a good response */
1094         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1095                 if (printk_ratelimit())
1096                         printk(KERN_WARNING
1097                                "ibmvscsi: reset bad SRP RSP type %d\n",
1098                                srp_rsp.srp.rsp.opcode);
1099                 return FAILED;
1100         }
1101
1102         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1103                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1104         else
1105                 rsp_rc = srp_rsp.srp.rsp.status;
1106
1107         if (rsp_rc) {
1108                 if (printk_ratelimit())
1109                         printk(KERN_WARNING
1110                                "ibmvscsi: reset code %d for task tag 0x%lx\n",
1111                                rsp_rc, tsk_mgmt->task_tag);
1112                 return FAILED;
1113         }
1114
1115         /* We need to find all commands for this LUN that have not yet been
1116          * responded to, and fail them with DID_RESET
1117          */
1118         spin_lock_irqsave(hostdata->host->host_lock, flags);
1119         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1120                 if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
1121                         if (tmp_evt->cmnd)
1122                                 tmp_evt->cmnd->result = (DID_RESET << 16);
1123                         list_del(&tmp_evt->list);
1124                         unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
1125                                        tmp_evt->hostdata->dev);
1126                         free_event_struct(&tmp_evt->hostdata->pool,
1127                                                    tmp_evt);
1128                         atomic_inc(&hostdata->request_limit);
1129                         if (tmp_evt->cmnd_done)
1130                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1131                         else if (tmp_evt->done)
1132                                 tmp_evt->done(tmp_evt);
1133                 }
1134         }
1135         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1136         return SUCCESS;
1137 }
1138
1139 /**
1140  * purge_requests: Our virtual adapter just shut down.  purge any sent requests
1141  * @hostdata:    the adapter
1142  */
1143 static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
1144 {
1145         struct srp_event_struct *tmp_evt, *pos;
1146         unsigned long flags;
1147
1148         spin_lock_irqsave(hostdata->host->host_lock, flags);
1149         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1150                 list_del(&tmp_evt->list);
1151                 if (tmp_evt->cmnd) {
1152                         tmp_evt->cmnd->result = (error_code << 16);
1153                         unmap_cmd_data(&tmp_evt->iu.srp.cmd,
1154                                        tmp_evt,
1155                                        tmp_evt->hostdata->dev);
1156                         if (tmp_evt->cmnd_done)
1157                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1158                 } else {
1159                         if (tmp_evt->done) {
1160                                 tmp_evt->done(tmp_evt);
1161                         }
1162                 }
1163                 free_event_struct(&tmp_evt->hostdata->pool, tmp_evt);
1164         }
1165         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1166 }
1167
1168 /**
1169  * ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
1170  * @crq:        Command/Response queue
1171  * @hostdata:   ibmvscsi_host_data of host
1172  *
1173 */
1174 void ibmvscsi_handle_crq(struct viosrp_crq *crq,
1175                          struct ibmvscsi_host_data *hostdata)
1176 {
1177         unsigned long flags;
1178         struct srp_event_struct *evt_struct =
1179             (struct srp_event_struct *)crq->IU_data_ptr;
1180         switch (crq->valid) {
1181         case 0xC0:              /* initialization */
1182                 switch (crq->format) {
1183                 case 0x01:      /* Initialization message */
1184                         printk(KERN_INFO "ibmvscsi: partner initialized\n");
1185                         /* Send back a response */
1186                         if (ibmvscsi_send_crq(hostdata,
1187                                               0xC002000000000000LL, 0) == 0) {
1188                                 /* Now login */
1189                                 send_srp_login(hostdata);
1190                         } else {
1191                                 printk(KERN_ERR
1192                                        "ibmvscsi: Unable to send init rsp\n");
1193                         }
1194
1195                         break;
1196                 case 0x02:      /* Initialization response */
1197                         printk(KERN_INFO
1198                                "ibmvscsi: partner initialization complete\n");
1199
1200                         /* Now login */
1201                         send_srp_login(hostdata);
1202                         break;
1203                 default:
1204                         printk(KERN_ERR "ibmvscsi: unknown crq message type\n");
1205                 }
1206                 return;
1207         case 0xFF:      /* Hypervisor telling us the connection is closed */
1208                 scsi_block_requests(hostdata->host);
1209                 atomic_set(&hostdata->request_limit, 0);
1210                 if (crq->format == 0x06) {
1211                         /* We need to re-setup the interpartition connection */
1212                         printk(KERN_INFO
1213                                "ibmvscsi: Re-enabling adapter!\n");
1214                         purge_requests(hostdata, DID_REQUEUE);
1215                         if ((ibmvscsi_reenable_crq_queue(&hostdata->queue,
1216                                                         hostdata) == 0) ||
1217                             (ibmvscsi_send_crq(hostdata,
1218                                                0xC001000000000000LL, 0))) {
1219                                         atomic_set(&hostdata->request_limit,
1220                                                    -1);
1221                                         printk(KERN_ERR
1222                                                "ibmvscsi: error after"
1223                                                " enable\n");
1224                         }
1225                 } else {
1226                         printk(KERN_INFO
1227                                "ibmvscsi: Virtual adapter failed rc %d!\n",
1228                                crq->format);
1229
1230                         purge_requests(hostdata, DID_ERROR);
1231                         if ((ibmvscsi_reset_crq_queue(&hostdata->queue,
1232                                                         hostdata)) ||
1233                             (ibmvscsi_send_crq(hostdata,
1234                                                0xC001000000000000LL, 0))) {
1235                                         atomic_set(&hostdata->request_limit,
1236                                                    -1);
1237                                         printk(KERN_ERR
1238                                                "ibmvscsi: error after reset\n");
1239                         }
1240                 }
1241                 scsi_unblock_requests(hostdata->host);
1242                 return;
1243         case 0x80:              /* real payload */
1244                 break;
1245         default:
1246                 printk(KERN_ERR
1247                        "ibmvscsi: got an invalid message type 0x%02x\n",
1248                        crq->valid);
1249                 return;
1250         }
1251
1252         /* The only kind of payload CRQs we should get are responses to
1253          * things we send. Make sure this response is to something we
1254          * actually sent
1255          */
1256         if (!valid_event_struct(&hostdata->pool, evt_struct)) {
1257                 printk(KERN_ERR
1258                        "ibmvscsi: returned correlation_token 0x%p is invalid!\n",
1259                        (void *)crq->IU_data_ptr);
1260                 return;
1261         }
1262
1263         if (atomic_read(&evt_struct->free)) {
1264                 printk(KERN_ERR
1265                        "ibmvscsi: received duplicate  correlation_token 0x%p!\n",
1266                        (void *)crq->IU_data_ptr);
1267                 return;
1268         }
1269
1270         if (crq->format == VIOSRP_SRP_FORMAT)
1271                 atomic_add(evt_struct->xfer_iu->srp.rsp.req_lim_delta,
1272                            &hostdata->request_limit);
1273
1274         if (evt_struct->done)
1275                 evt_struct->done(evt_struct);
1276         else
1277                 printk(KERN_ERR
1278                        "ibmvscsi: returned done() is NULL; not running it!\n");
1279
1280         /*
1281          * Lock the host_lock before messing with these structures, since we
1282          * are running in a task context
1283          */
1284         spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
1285         list_del(&evt_struct->list);
1286         free_event_struct(&evt_struct->hostdata->pool, evt_struct);
1287         spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
1288 }
1289
1290 /**
1291  * ibmvscsi_get_host_config: Send the command to the server to get host
1292  * configuration data.  The data is opaque to us.
1293  */
1294 static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
1295                                    unsigned char *buffer, int length)
1296 {
1297         struct viosrp_host_config *host_config;
1298         struct srp_event_struct *evt_struct;
1299         dma_addr_t addr;
1300         int rc;
1301
1302         evt_struct = get_event_struct(&hostdata->pool);
1303         if (!evt_struct) {
1304                 printk(KERN_ERR
1305                        "ibmvscsi: could't allocate event for HOST_CONFIG!\n");
1306                 return -1;
1307         }
1308
1309         init_event_struct(evt_struct,
1310                           sync_completion,
1311                           VIOSRP_MAD_FORMAT,
1312                           init_timeout * HZ);
1313
1314         host_config = &evt_struct->iu.mad.host_config;
1315
1316         /* Set up a lun reset SRP command */
1317         memset(host_config, 0x00, sizeof(*host_config));
1318         host_config->common.type = VIOSRP_HOST_CONFIG_TYPE;
1319         host_config->common.length = length;
1320         host_config->buffer = addr = dma_map_single(hostdata->dev, buffer,
1321                                                     length,
1322                                                     DMA_BIDIRECTIONAL);
1323
1324         if (dma_mapping_error(host_config->buffer)) {
1325                 printk(KERN_ERR
1326                        "ibmvscsi: dma_mapping error " "getting host config\n");
1327                 free_event_struct(&hostdata->pool, evt_struct);
1328                 return -1;
1329         }
1330
1331         init_completion(&evt_struct->comp);
1332         rc = ibmvscsi_send_srp_event(evt_struct, hostdata);
1333         if (rc == 0)
1334                 wait_for_completion(&evt_struct->comp);
1335         dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL);
1336
1337         return rc;
1338 }
1339
1340 /* ------------------------------------------------------------
1341  * sysfs attributes
1342  */
1343 static ssize_t show_host_srp_version(struct class_device *class_dev, char *buf)
1344 {
1345         struct Scsi_Host *shost = class_to_shost(class_dev);
1346         struct ibmvscsi_host_data *hostdata =
1347             (struct ibmvscsi_host_data *)shost->hostdata;
1348         int len;
1349
1350         len = snprintf(buf, PAGE_SIZE, "%s\n",
1351                        hostdata->madapter_info.srp_version);
1352         return len;
1353 }
1354
1355 static struct class_device_attribute ibmvscsi_host_srp_version = {
1356         .attr = {
1357                  .name = "srp_version",
1358                  .mode = S_IRUGO,
1359                  },
1360         .show = show_host_srp_version,
1361 };
1362
1363 static ssize_t show_host_partition_name(struct class_device *class_dev,
1364                                         char *buf)
1365 {
1366         struct Scsi_Host *shost = class_to_shost(class_dev);
1367         struct ibmvscsi_host_data *hostdata =
1368             (struct ibmvscsi_host_data *)shost->hostdata;
1369         int len;
1370
1371         len = snprintf(buf, PAGE_SIZE, "%s\n",
1372                        hostdata->madapter_info.partition_name);
1373         return len;
1374 }
1375
1376 static struct class_device_attribute ibmvscsi_host_partition_name = {
1377         .attr = {
1378                  .name = "partition_name",
1379                  .mode = S_IRUGO,
1380                  },
1381         .show = show_host_partition_name,
1382 };
1383
1384 static ssize_t show_host_partition_number(struct class_device *class_dev,
1385                                           char *buf)
1386 {
1387         struct Scsi_Host *shost = class_to_shost(class_dev);
1388         struct ibmvscsi_host_data *hostdata =
1389             (struct ibmvscsi_host_data *)shost->hostdata;
1390         int len;
1391
1392         len = snprintf(buf, PAGE_SIZE, "%d\n",
1393                        hostdata->madapter_info.partition_number);
1394         return len;
1395 }
1396
1397 static struct class_device_attribute ibmvscsi_host_partition_number = {
1398         .attr = {
1399                  .name = "partition_number",
1400                  .mode = S_IRUGO,
1401                  },
1402         .show = show_host_partition_number,
1403 };
1404
1405 static ssize_t show_host_mad_version(struct class_device *class_dev, char *buf)
1406 {
1407         struct Scsi_Host *shost = class_to_shost(class_dev);
1408         struct ibmvscsi_host_data *hostdata =
1409             (struct ibmvscsi_host_data *)shost->hostdata;
1410         int len;
1411
1412         len = snprintf(buf, PAGE_SIZE, "%d\n",
1413                        hostdata->madapter_info.mad_version);
1414         return len;
1415 }
1416
1417 static struct class_device_attribute ibmvscsi_host_mad_version = {
1418         .attr = {
1419                  .name = "mad_version",
1420                  .mode = S_IRUGO,
1421                  },
1422         .show = show_host_mad_version,
1423 };
1424
1425 static ssize_t show_host_os_type(struct class_device *class_dev, char *buf)
1426 {
1427         struct Scsi_Host *shost = class_to_shost(class_dev);
1428         struct ibmvscsi_host_data *hostdata =
1429             (struct ibmvscsi_host_data *)shost->hostdata;
1430         int len;
1431
1432         len = snprintf(buf, PAGE_SIZE, "%d\n", hostdata->madapter_info.os_type);
1433         return len;
1434 }
1435
1436 static struct class_device_attribute ibmvscsi_host_os_type = {
1437         .attr = {
1438                  .name = "os_type",
1439                  .mode = S_IRUGO,
1440                  },
1441         .show = show_host_os_type,
1442 };
1443
1444 static ssize_t show_host_config(struct class_device *class_dev, char *buf)
1445 {
1446         struct Scsi_Host *shost = class_to_shost(class_dev);
1447         struct ibmvscsi_host_data *hostdata =
1448             (struct ibmvscsi_host_data *)shost->hostdata;
1449
1450         /* returns null-terminated host config data */
1451         if (ibmvscsi_do_host_config(hostdata, buf, PAGE_SIZE) == 0)
1452                 return strlen(buf);
1453         else
1454                 return 0;
1455 }
1456
1457 static struct class_device_attribute ibmvscsi_host_config = {
1458         .attr = {
1459                  .name = "config",
1460                  .mode = S_IRUGO,
1461                  },
1462         .show = show_host_config,
1463 };
1464
1465 static struct class_device_attribute *ibmvscsi_attrs[] = {
1466         &ibmvscsi_host_srp_version,
1467         &ibmvscsi_host_partition_name,
1468         &ibmvscsi_host_partition_number,
1469         &ibmvscsi_host_mad_version,
1470         &ibmvscsi_host_os_type,
1471         &ibmvscsi_host_config,
1472         NULL
1473 };
1474
1475 /* ------------------------------------------------------------
1476  * SCSI driver registration
1477  */
1478 static struct scsi_host_template driver_template = {
1479         .module = THIS_MODULE,
1480         .name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
1481         .proc_name = "ibmvscsi",
1482         .queuecommand = ibmvscsi_queuecommand,
1483         .eh_abort_handler = ibmvscsi_eh_abort_handler,
1484         .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
1485         .cmd_per_lun = 16,
1486         .can_queue = 1,         /* Updated after SRP_LOGIN */
1487         .this_id = -1,
1488         .sg_tablesize = SG_ALL,
1489         .use_clustering = ENABLE_CLUSTERING,
1490         .shost_attrs = ibmvscsi_attrs,
1491 };
1492
1493 /**
1494  * Called by bus code for each adapter
1495  */
1496 static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
1497 {
1498         struct ibmvscsi_host_data *hostdata;
1499         struct Scsi_Host *host;
1500         struct device *dev = &vdev->dev;
1501         unsigned long wait_switch = 0;
1502         int rc;
1503
1504         vdev->dev.driver_data = NULL;
1505
1506         host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
1507         if (!host) {
1508                 printk(KERN_ERR "ibmvscsi: couldn't allocate host data\n");
1509                 goto scsi_host_alloc_failed;
1510         }
1511
1512         hostdata = (struct ibmvscsi_host_data *)host->hostdata;
1513         memset(hostdata, 0x00, sizeof(*hostdata));
1514         INIT_LIST_HEAD(&hostdata->sent);
1515         hostdata->host = host;
1516         hostdata->dev = dev;
1517         atomic_set(&hostdata->request_limit, -1);
1518         hostdata->host->max_sectors = 32 * 8; /* default max I/O 32 pages */
1519
1520         rc = ibmvscsi_init_crq_queue(&hostdata->queue, hostdata, max_requests);
1521         if (rc != 0 && rc != H_RESOURCE) {
1522                 printk(KERN_ERR "ibmvscsi: couldn't initialize crq\n");
1523                 goto init_crq_failed;
1524         }
1525         if (initialize_event_pool(&hostdata->pool, max_requests, hostdata) != 0) {
1526                 printk(KERN_ERR "ibmvscsi: couldn't initialize event pool\n");
1527                 goto init_pool_failed;
1528         }
1529
1530         host->max_lun = 8;
1531         host->max_id = max_id;
1532         host->max_channel = max_channel;
1533
1534         if (scsi_add_host(hostdata->host, hostdata->dev))
1535                 goto add_host_failed;
1536
1537         /* Try to send an initialization message.  Note that this is allowed
1538          * to fail if the other end is not acive.  In that case we don't
1539          * want to scan
1540          */
1541         if (ibmvscsi_send_crq(hostdata, 0xC001000000000000LL, 0) == 0
1542             || rc == H_RESOURCE) {
1543                 /*
1544                  * Wait around max init_timeout secs for the adapter to finish
1545                  * initializing. When we are done initializing, we will have a
1546                  * valid request_limit.  We don't want Linux scanning before
1547                  * we are ready.
1548                  */
1549                 for (wait_switch = jiffies + (init_timeout * HZ);
1550                      time_before(jiffies, wait_switch) &&
1551                      atomic_read(&hostdata->request_limit) < 2;) {
1552
1553                         msleep(10);
1554                 }
1555
1556                 /* if we now have a valid request_limit, initiate a scan */
1557                 if (atomic_read(&hostdata->request_limit) > 0)
1558                         scsi_scan_host(host);
1559         }
1560
1561         vdev->dev.driver_data = hostdata;
1562         return 0;
1563
1564       add_host_failed:
1565         release_event_pool(&hostdata->pool, hostdata);
1566       init_pool_failed:
1567         ibmvscsi_release_crq_queue(&hostdata->queue, hostdata, max_requests);
1568       init_crq_failed:
1569         scsi_host_put(host);
1570       scsi_host_alloc_failed:
1571         return -1;
1572 }
1573
1574 static int ibmvscsi_remove(struct vio_dev *vdev)
1575 {
1576         struct ibmvscsi_host_data *hostdata = vdev->dev.driver_data;
1577         release_event_pool(&hostdata->pool, hostdata);
1578         ibmvscsi_release_crq_queue(&hostdata->queue, hostdata,
1579                                    max_requests);
1580
1581         scsi_remove_host(hostdata->host);
1582         scsi_host_put(hostdata->host);
1583
1584         return 0;
1585 }
1586
1587 /**
1588  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we
1589  * support.
1590  */
1591 static struct vio_device_id ibmvscsi_device_table[] __devinitdata = {
1592         {"vscsi", "IBM,v-scsi"},
1593         { "", "" }
1594 };
1595 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
1596
1597 static struct vio_driver ibmvscsi_driver = {
1598         .id_table = ibmvscsi_device_table,
1599         .probe = ibmvscsi_probe,
1600         .remove = ibmvscsi_remove,
1601         .driver = {
1602                 .name = "ibmvscsi",
1603                 .owner = THIS_MODULE,
1604         }
1605 };
1606
1607 int __init ibmvscsi_module_init(void)
1608 {
1609         return vio_register_driver(&ibmvscsi_driver);
1610 }
1611
1612 void __exit ibmvscsi_module_exit(void)
1613 {
1614         vio_unregister_driver(&ibmvscsi_driver);
1615 }
1616
1617 module_init(ibmvscsi_module_init);
1618 module_exit(ibmvscsi_module_exit);