drivers/s390/scsi/zfcp_qdio.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * zfcp device driver
   4  *
   5  * Setup and helper functions to access QDIO.
   6  *
   7  * Copyright IBM Corp. 2002, 2020
   8  */
   9
  10 #define KMSG_COMPONENT "zfcp"
  11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  12
  13 #include <linux/lockdep.h>
  14 #include <linux/slab.h>
  15 #include <linux/module.h>
  16 #include "zfcp_ext.h"
  17 #include "zfcp_qdio.h"
  18
  19 static bool enable_multibuffer = true;
  20 module_param_named(datarouter, enable_multibuffer, bool, 0400);
  21 MODULE_PARM_DESC(datarouter, "Enable hardware data router support (default on)");
  22
  23 #define ZFCP_QDIO_REQUEST_RESCAN_MSECS  (MSEC_PER_SEC * 10)
  24 #define ZFCP_QDIO_REQUEST_SCAN_MSECS    MSEC_PER_SEC
  25
  26 static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *dbftag,
  27                                     unsigned int qdio_err)
  28 {
  29         struct zfcp_adapter *adapter = qdio->adapter;
  30
  31         dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n");
  32
  33         if (qdio_err & QDIO_ERROR_SLSB_STATE) {
  34                 zfcp_qdio_siosl(adapter);
  35                 zfcp_erp_adapter_shutdown(adapter, 0, dbftag);
  36                 return;
  37         }
  38         zfcp_erp_adapter_reopen(adapter,
  39                                 ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED |
  40                                 ZFCP_STATUS_COMMON_ERP_FAILED, dbftag);
  41 }
  42
  43 static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt)
  44 {
  45         int i, sbal_idx;
  46
  47         for (i = first; i < first + cnt; i++) {
  48                 sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q;
  49                 memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer));
  50         }
  51 }
  52
  53 /* this needs to be called prior to updating the queue fill level */
  54 static inline void zfcp_qdio_account(struct zfcp_qdio *qdio)
  55 {
  56         unsigned long long now, span;
  57         int used;
  58
  59         now = get_tod_clock_monotonic();
  60         span = (now - qdio->req_q_time) >> 12;
  61         used = QDIO_MAX_BUFFERS_PER_Q - atomic_read(&qdio->req_q_free);
  62         qdio->req_q_util += used * span;
  63         qdio->req_q_time = now;
  64 }
  65
  66 static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err,
  67                               int queue_no, int idx, int count,
  68                               unsigned long parm)
  69 {
  70         struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
  71
  72         zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err);
  73 }
  74
  75 static void zfcp_qdio_request_tasklet(struct tasklet_struct *tasklet)
  76 {
  77         struct zfcp_qdio *qdio = from_tasklet(qdio, tasklet, request_tasklet);
  78         struct ccw_device *cdev = qdio->adapter->ccw_device;
  79         unsigned int start, error;
  80         int completed;
  81
  82         completed = qdio_inspect_queue(cdev, 0, false, &start, &error);
  83         if (completed > 0) {
  84                 if (error) {
  85                         zfcp_qdio_handler_error(qdio, "qdreqt1", error);
  86                 } else {
  87                         /* cleanup all SBALs being program-owned now */
  88                         zfcp_qdio_zero_sbals(qdio->req_q, start, completed);
  89
  90                         spin_lock_irq(&qdio->stat_lock);
  91                         zfcp_qdio_account(qdio);
  92                         spin_unlock_irq(&qdio->stat_lock);
  93                         atomic_add(completed, &qdio->req_q_free);
  94                         wake_up(&qdio->req_q_wq);
  95                 }
  96         }
  97
  98         if (atomic_read(&qdio->req_q_free) < QDIO_MAX_BUFFERS_PER_Q)
  99                 timer_reduce(&qdio->request_timer,
 100                              jiffies + msecs_to_jiffies(ZFCP_QDIO_REQUEST_RESCAN_MSECS));
 101 }
 102
 103 static void zfcp_qdio_request_timer(struct timer_list *timer)
 104 {
 105         struct zfcp_qdio *qdio = from_timer(qdio, timer, request_timer);
 106
 107         tasklet_schedule(&qdio->request_tasklet);
 108 }
 109
 110 static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
 111                                int queue_no, int idx, int count,
 112                                unsigned long parm)
 113 {
 114         struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
 115         struct zfcp_adapter *adapter = qdio->adapter;
 116         int sbal_no, sbal_idx;
 117
 118         if (unlikely(qdio_err)) {
 119                 if (zfcp_adapter_multi_buffer_active(adapter)) {
 120                         void *pl[ZFCP_QDIO_MAX_SBALS_PER_REQ + 1];
 121                         struct qdio_buffer_element *sbale;
 122                         u64 req_id;
 123                         u8 scount;
 124
 125                         memset(pl, 0,
 126                                ZFCP_QDIO_MAX_SBALS_PER_REQ * sizeof(void *));
 127                         sbale = qdio->res_q[idx]->element;
 128                         req_id = sbale->addr;
 129                         scount = min(sbale->scount + 1,
 130                                      ZFCP_QDIO_MAX_SBALS_PER_REQ + 1);
 131                                      /* incl. signaling SBAL */
 132
 133                         for (sbal_no = 0; sbal_no < scount; sbal_no++) {
 134                                 sbal_idx = (idx + sbal_no) %
 135                                         QDIO_MAX_BUFFERS_PER_Q;
 136                                 pl[sbal_no] = qdio->res_q[sbal_idx];
 137                         }
 138                         zfcp_dbf_hba_def_err(adapter, req_id, scount, pl);
 139                 }
 140                 zfcp_qdio_handler_error(qdio, "qdires1", qdio_err);
 141                 return;
 142         }
 143
 144         /*
 145          * go through all SBALs from input queue currently
 146          * returned by QDIO layer
 147          */
 148         for (sbal_no = 0; sbal_no < count; sbal_no++) {
 149                 sbal_idx = (idx + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;
 150                 /* go through all SBALEs of SBAL */
 151                 zfcp_fsf_reqid_check(qdio, sbal_idx);
 152         }
 153
 154         /*
 155          * put SBALs back to response queue
 156          */
 157         if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, idx, count, NULL))
 158                 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdires2");
 159 }
 160
 161 static void zfcp_qdio_irq_tasklet(struct tasklet_struct *tasklet)
 162 {
 163         struct zfcp_qdio *qdio = from_tasklet(qdio, tasklet, irq_tasklet);
 164         struct ccw_device *cdev = qdio->adapter->ccw_device;
 165         unsigned int start, error;
 166         int completed;
 167
 168         if (atomic_read(&qdio->req_q_free) < QDIO_MAX_BUFFERS_PER_Q)
 169                 tasklet_schedule(&qdio->request_tasklet);
 170
 171         /* Check the Response Queue: */
 172         completed = qdio_inspect_queue(cdev, 0, true, &start, &error);
 173         if (completed < 0)
 174                 return;
 175         if (completed > 0)
 176                 zfcp_qdio_int_resp(cdev, error, 0, start, completed,
 177                                    (unsigned long) qdio);
 178
 179         if (qdio_start_irq(cdev))
 180                 /* More work pending: */
 181                 tasklet_schedule(&qdio->irq_tasklet);
 182 }
 183
 184 static void zfcp_qdio_poll(struct ccw_device *cdev, unsigned long data)
 185 {
 186         struct zfcp_qdio *qdio = (struct zfcp_qdio *) data;
 187
 188         tasklet_schedule(&qdio->irq_tasklet);
 189 }
 190
 191 static struct qdio_buffer_element *
 192 zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
 193 {
 194         struct qdio_buffer_element *sbale;
 195
 196         /* set last entry flag in current SBALE of current SBAL */
 197         sbale = zfcp_qdio_sbale_curr(qdio, q_req);
 198         sbale->eflags |= SBAL_EFLAGS_LAST_ENTRY;
 199
 200         /* don't exceed last allowed SBAL */
 201         if (q_req->sbal_last == q_req->sbal_limit)
 202                 return NULL;
 203
 204         /* set chaining flag in first SBALE of current SBAL */
 205         sbale = zfcp_qdio_sbale_req(qdio, q_req);
 206         sbale->sflags |= SBAL_SFLAGS0_MORE_SBALS;
 207
 208         /* calculate index of next SBAL */
 209         q_req->sbal_last++;
 210         q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q;
 211
 212         /* keep this requests number of SBALs up-to-date */
 213         q_req->sbal_number++;
 214         BUG_ON(q_req->sbal_number > ZFCP_QDIO_MAX_SBALS_PER_REQ);
 215
 216         /* start at first SBALE of new SBAL */
 217         q_req->sbale_curr = 0;
 218
 219         /* set storage-block type for new SBAL */
 220         sbale = zfcp_qdio_sbale_curr(qdio, q_req);
 221         sbale->sflags |= q_req->sbtype;
 222
 223         return sbale;
 224 }
 225
 226 static struct qdio_buffer_element *
 227 zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
 228 {
 229         if (q_req->sbale_curr == qdio->max_sbale_per_sbal - 1)
 230                 return zfcp_qdio_sbal_chain(qdio, q_req);
 231         q_req->sbale_curr++;
 232         return zfcp_qdio_sbale_curr(qdio, q_req);
 233 }
 234
 235 /**
 236  * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
 237  * @qdio: pointer to struct zfcp_qdio
 238  * @q_req: pointer to struct zfcp_qdio_req
 239  * @sg: scatter-gather list
 240  * Returns: zero or -EINVAL on error
 241  */
 242 int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,
 243                             struct scatterlist *sg)
 244 {
 245         struct qdio_buffer_element *sbale;
 246
 247         /* set storage-block type for this request */
 248         sbale = zfcp_qdio_sbale_req(qdio, q_req);
 249         sbale->sflags |= q_req->sbtype;
 250
 251         for (; sg; sg = sg_next(sg)) {
 252                 sbale = zfcp_qdio_sbale_next(qdio, q_req);
 253                 if (!sbale) {
 254                         atomic_inc(&qdio->req_q_full);
 255                         zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,
 256                                              q_req->sbal_number);
 257                         return -EINVAL;
 258                 }
 259                 sbale->addr = sg_phys(sg);
 260                 sbale->length = sg->length;
 261         }
 262         return 0;
 263 }
 264
 265 static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio)
 266 {
 267         if (atomic_read(&qdio->req_q_free) ||
 268             !(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
 269                 return 1;
 270         return 0;
 271 }
 272
 273 /**
 274  * zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary
 275  * @qdio: pointer to struct zfcp_qdio
 276  *
 277  * The req_q_lock must be held by the caller of this function, and
 278  * this function may only be called from process context; it will
 279  * sleep when waiting for a free sbal.
 280  *
 281  * Returns: 0 on success, -EIO if there is no free sbal after waiting.
 282  */
 283 int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio)
 284 {
 285         long ret;
 286
 287         ret = wait_event_interruptible_lock_irq_timeout(qdio->req_q_wq,
 288                        zfcp_qdio_sbal_check(qdio), qdio->req_q_lock, 5 * HZ);
 289
 290         if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
 291                 return -EIO;
 292
 293         if (ret > 0)
 294                 return 0;
 295
 296         if (!ret) {
 297                 atomic_inc(&qdio->req_q_full);
 298                 /* assume hanging outbound queue, try queue recovery */
 299                 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1");
 300         }
 301
 302         return -EIO;
 303 }
 304
 305 /**
 306  * zfcp_qdio_send - send req to QDIO
 307  * @qdio: pointer to struct zfcp_qdio
 308  * @q_req: pointer to struct zfcp_qdio_req
 309  * Returns: 0 on success, error otherwise
 310  */
 311 int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
 312 {
 313         int retval;
 314         u8 sbal_number = q_req->sbal_number;
 315
 316         /*
 317          * This should actually be a spin_lock_bh(stat_lock), to protect against
 318          * Request Queue completion processing in tasklet context.
 319          * But we can't do so (and are safe), as we always get called with IRQs
 320          * disabled by spin_lock_irq[save](req_q_lock).
 321          */
 322         lockdep_assert_irqs_disabled();
 323         spin_lock(&qdio->stat_lock);
 324         zfcp_qdio_account(qdio);
 325         spin_unlock(&qdio->stat_lock);
 326
 327         atomic_sub(sbal_number, &qdio->req_q_free);
 328
 329         retval = do_QDIO(qdio->adapter->ccw_device, QDIO_FLAG_SYNC_OUTPUT, 0,
 330                          q_req->sbal_first, sbal_number, NULL);
 331
 332         if (unlikely(retval)) {
 333                 /* Failed to submit the IO, roll back our modifications. */
 334                 atomic_add(sbal_number, &qdio->req_q_free);
 335                 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,
 336                                      sbal_number);
 337                 return retval;
 338         }
 339
 340         if (atomic_read(&qdio->req_q_free) <= 2 * ZFCP_QDIO_MAX_SBALS_PER_REQ)
 341                 tasklet_schedule(&qdio->request_tasklet);
 342         else
 343                 timer_reduce(&qdio->request_timer,
 344                              jiffies + msecs_to_jiffies(ZFCP_QDIO_REQUEST_SCAN_MSECS));
 345
 346         /* account for transferred buffers */
 347         qdio->req_q_idx += sbal_number;
 348         qdio->req_q_idx %= QDIO_MAX_BUFFERS_PER_Q;
 349
 350         return 0;
 351 }
 352
 353 /**
 354  * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data
 355  * @qdio: pointer to struct zfcp_qdio
 356  * Returns: -ENOMEM on memory allocation error or return value from
 357  *          qdio_allocate
 358  */
 359 static int zfcp_qdio_allocate(struct zfcp_qdio *qdio)
 360 {
 361         int ret;
 362
 363         ret = qdio_alloc_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
 364         if (ret)
 365                 return -ENOMEM;
 366
 367         ret = qdio_alloc_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
 368         if (ret)
 369                 goto free_req_q;
 370
 371         init_waitqueue_head(&qdio->req_q_wq);
 372
 373         ret = qdio_allocate(qdio->adapter->ccw_device, 1, 1);
 374         if (ret)
 375                 goto free_res_q;
 376
 377         return 0;
 378
 379 free_res_q:
 380         qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
 381 free_req_q:
 382         qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
 383         return ret;
 384 }
 385
 386 /**
 387  * zfcp_close_qdio - close qdio queues for an adapter
 388  * @qdio: pointer to structure zfcp_qdio
 389  */
 390 void zfcp_qdio_close(struct zfcp_qdio *qdio)
 391 {
 392         struct zfcp_adapter *adapter = qdio->adapter;
 393         int idx, count;
 394
 395         if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
 396                 return;
 397
 398         /* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */
 399         spin_lock_irq(&qdio->req_q_lock);
 400         atomic_andnot(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status);
 401         spin_unlock_irq(&qdio->req_q_lock);
 402
 403         wake_up(&qdio->req_q_wq);
 404
 405         tasklet_disable(&qdio->irq_tasklet);
 406         tasklet_disable(&qdio->request_tasklet);
 407         del_timer_sync(&qdio->request_timer);
 408         qdio_stop_irq(adapter->ccw_device);
 409         qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR);
 410
 411         /* cleanup used outbound sbals */
 412         count = atomic_read(&qdio->req_q_free);
 413         if (count < QDIO_MAX_BUFFERS_PER_Q) {
 414                 idx = (qdio->req_q_idx + count) % QDIO_MAX_BUFFERS_PER_Q;
 415                 count = QDIO_MAX_BUFFERS_PER_Q - count;
 416                 zfcp_qdio_zero_sbals(qdio->req_q, idx, count);
 417         }
 418         qdio->req_q_idx = 0;
 419         atomic_set(&qdio->req_q_free, 0);
 420 }
 421
 422 void zfcp_qdio_shost_update(struct zfcp_adapter *const adapter,
 423                             const struct zfcp_qdio *const qdio)
 424 {
 425         struct Scsi_Host *const shost = adapter->scsi_host;
 426
 427         if (shost == NULL)
 428                 return;
 429
 430         shost->sg_tablesize = qdio->max_sbale_per_req;
 431         shost->max_sectors = qdio->max_sbale_per_req * 8;
 432 }
 433
 434 /**
 435  * zfcp_qdio_open - prepare and initialize response queue
 436  * @qdio: pointer to struct zfcp_qdio
 437  * Returns: 0 on success, otherwise -EIO
 438  */
 439 int zfcp_qdio_open(struct zfcp_qdio *qdio)
 440 {
 441         struct qdio_buffer **input_sbals[1] = {qdio->res_q};
 442         struct qdio_buffer **output_sbals[1] = {qdio->req_q};
 443         struct qdio_buffer_element *sbale;
 444         struct qdio_initialize init_data = {0};
 445         struct zfcp_adapter *adapter = qdio->adapter;
 446         struct ccw_device *cdev = adapter->ccw_device;
 447         struct qdio_ssqd_desc ssqd;
 448         int cc;
 449
 450         if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)
 451                 return -EIO;
 452
 453         atomic_andnot(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,
 454                           &qdio->adapter->status);
 455
 456         init_data.q_format = QDIO_ZFCP_QFMT;
 457         init_data.qib_rflags = QIB_RFLAGS_ENABLE_DATA_DIV;
 458         if (enable_multibuffer)
 459                 init_data.qdr_ac |= QDR_AC_MULTI_BUFFER_ENABLE;
 460         init_data.no_input_qs = 1;
 461         init_data.no_output_qs = 1;
 462         init_data.input_handler = zfcp_qdio_int_resp;
 463         init_data.output_handler = zfcp_qdio_int_req;
 464         init_data.irq_poll = zfcp_qdio_poll;
 465         init_data.int_parm = (unsigned long) qdio;
 466         init_data.input_sbal_addr_array = input_sbals;
 467         init_data.output_sbal_addr_array = output_sbals;
 468
 469         if (qdio_establish(cdev, &init_data))
 470                 goto failed_establish;
 471
 472         if (qdio_get_ssqd_desc(cdev, &ssqd))
 473                 goto failed_qdio;
 474
 475         if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED)
 476                 atomic_or(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED,
 477                                 &qdio->adapter->status);
 478
 479         if (ssqd.qdioac2 & CHSC_AC2_MULTI_BUFFER_ENABLED) {
 480                 atomic_or(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);
 481                 qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER;
 482         } else {
 483                 atomic_andnot(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);
 484                 qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER - 1;
 485         }
 486
 487         qdio->max_sbale_per_req =
 488                 ZFCP_QDIO_MAX_SBALS_PER_REQ * qdio->max_sbale_per_sbal
 489                 - 2;
 490         if (qdio_activate(cdev))
 491                 goto failed_qdio;
 492
 493         for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) {
 494                 sbale = &(qdio->res_q[cc]->element[0]);
 495                 sbale->length = 0;
 496                 sbale->eflags = SBAL_EFLAGS_LAST_ENTRY;
 497                 sbale->sflags = 0;
 498                 sbale->addr = 0;
 499         }
 500
 501         if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0, QDIO_MAX_BUFFERS_PER_Q,
 502                     NULL))
 503                 goto failed_qdio;
 504
 505         /* set index of first available SBALS / number of available SBALS */
 506         qdio->req_q_idx = 0;
 507         atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q);
 508         atomic_or(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status);
 509
 510         /* Enable processing for Request Queue completions: */
 511         tasklet_enable(&qdio->request_tasklet);
 512         /* Enable processing for QDIO interrupts: */
 513         tasklet_enable(&qdio->irq_tasklet);
 514         /* This results in a qdio_start_irq(): */
 515         tasklet_schedule(&qdio->irq_tasklet);
 516
 517         zfcp_qdio_shost_update(adapter, qdio);
 518
 519         return 0;
 520
 521 failed_qdio:
 522         qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
 523 failed_establish:
 524         dev_err(&cdev->dev,
 525                 "Setting up the QDIO connection to the FCP adapter failed\n");
 526         return -EIO;
 527 }
 528
 529 void zfcp_qdio_destroy(struct zfcp_qdio *qdio)
 530 {
 531         if (!qdio)
 532                 return;
 533
 534         tasklet_kill(&qdio->irq_tasklet);
 535         tasklet_kill(&qdio->request_tasklet);
 536
 537         if (qdio->adapter->ccw_device)
 538                 qdio_free(qdio->adapter->ccw_device);
 539
 540         qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
 541         qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
 542         kfree(qdio);
 543 }
 544
 545 int zfcp_qdio_setup(struct zfcp_adapter *adapter)
 546 {
 547         struct zfcp_qdio *qdio;
 548
 549         qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL);
 550         if (!qdio)
 551                 return -ENOMEM;
 552
 553         qdio->adapter = adapter;
 554
 555         if (zfcp_qdio_allocate(qdio)) {
 556                 kfree(qdio);
 557                 return -ENOMEM;
 558         }
 559
 560         spin_lock_init(&qdio->req_q_lock);
 561         spin_lock_init(&qdio->stat_lock);
 562         timer_setup(&qdio->request_timer, zfcp_qdio_request_timer, 0);
 563         tasklet_setup(&qdio->irq_tasklet, zfcp_qdio_irq_tasklet);
 564         tasklet_setup(&qdio->request_tasklet, zfcp_qdio_request_tasklet);
 565         tasklet_disable(&qdio->irq_tasklet);
 566         tasklet_disable(&qdio->request_tasklet);
 567
 568         adapter->qdio = qdio;
 569         return 0;
 570 }
 571
 572 /**
 573  * zfcp_qdio_siosl - Trigger logging in FCP channel
 574  * @adapter: The zfcp_adapter where to trigger logging
 575  *
 576  * Call the cio siosl function to trigger hardware logging.  This
 577  * wrapper function sets a flag to ensure hardware logging is only
 578  * triggered once before going through qdio shutdown.
 579  *
 580  * The triggers are always run from qdio tasklet context, so no
 581  * additional synchronization is necessary.
 582  */
 583 void zfcp_qdio_siosl(struct zfcp_adapter *adapter)
 584 {
 585         int rc;
 586
 587         if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED)
 588                 return;
 589
 590         rc = ccw_device_siosl(adapter->ccw_device);
 591         if (!rc)
 592                 atomic_or(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,
 593                                 &adapter->status);
 594 }