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         if (unlikely(qdio_err)) {
  73                 zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err);
  74                 return;
  75         }
  76 }
  77
  78 static void zfcp_qdio_request_tasklet(struct tasklet_struct *tasklet)
  79 {
  80         struct zfcp_qdio *qdio = from_tasklet(qdio, tasklet, request_tasklet);
  81         struct ccw_device *cdev = qdio->adapter->ccw_device;
  82         unsigned int start, error;
  83         int completed;
  84
  85         completed = qdio_inspect_queue(cdev, 0, false, &start, &error);
  86         if (completed > 0) {
  87                 if (error) {
  88                         zfcp_qdio_handler_error(qdio, "qdreqt1", error);
  89                 } else {
  90                         /* cleanup all SBALs being program-owned now */
  91                         zfcp_qdio_zero_sbals(qdio->req_q, start, completed);
  92
  93                         spin_lock_irq(&qdio->stat_lock);
  94                         zfcp_qdio_account(qdio);
  95                         spin_unlock_irq(&qdio->stat_lock);
  96                         atomic_add(completed, &qdio->req_q_free);
  97                         wake_up(&qdio->req_q_wq);
  98                 }
  99         }
 100
 101         if (atomic_read(&qdio->req_q_free) < QDIO_MAX_BUFFERS_PER_Q)
 102                 timer_reduce(&qdio->request_timer,
 103                              jiffies + msecs_to_jiffies(ZFCP_QDIO_REQUEST_RESCAN_MSECS));
 104 }
 105
 106 static void zfcp_qdio_request_timer(struct timer_list *timer)
 107 {
 108         struct zfcp_qdio *qdio = from_timer(qdio, timer, request_timer);
 109
 110         tasklet_schedule(&qdio->request_tasklet);
 111 }
 112
 113 static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
 114                                int queue_no, int idx, int count,
 115                                unsigned long parm)
 116 {
 117         struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
 118         struct zfcp_adapter *adapter = qdio->adapter;
 119         int sbal_no, sbal_idx;
 120
 121         if (unlikely(qdio_err)) {
 122                 if (zfcp_adapter_multi_buffer_active(adapter)) {
 123                         void *pl[ZFCP_QDIO_MAX_SBALS_PER_REQ + 1];
 124                         struct qdio_buffer_element *sbale;
 125                         u64 req_id;
 126                         u8 scount;
 127
 128                         memset(pl, 0,
 129                                ZFCP_QDIO_MAX_SBALS_PER_REQ * sizeof(void *));
 130                         sbale = qdio->res_q[idx]->element;
 131                         req_id = sbale->addr;
 132                         scount = min(sbale->scount + 1,
 133                                      ZFCP_QDIO_MAX_SBALS_PER_REQ + 1);
 134                                      /* incl. signaling SBAL */
 135
 136                         for (sbal_no = 0; sbal_no < scount; sbal_no++) {
 137                                 sbal_idx = (idx + sbal_no) %
 138                                         QDIO_MAX_BUFFERS_PER_Q;
 139                                 pl[sbal_no] = qdio->res_q[sbal_idx];
 140                         }
 141                         zfcp_dbf_hba_def_err(adapter, req_id, scount, pl);
 142                 }
 143                 zfcp_qdio_handler_error(qdio, "qdires1", qdio_err);
 144                 return;
 145         }
 146
 147         /*
 148          * go through all SBALs from input queue currently
 149          * returned by QDIO layer
 150          */
 151         for (sbal_no = 0; sbal_no < count; sbal_no++) {
 152                 sbal_idx = (idx + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;
 153                 /* go through all SBALEs of SBAL */
 154                 zfcp_fsf_reqid_check(qdio, sbal_idx);
 155         }
 156
 157         /*
 158          * put SBALs back to response queue
 159          */
 160         if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, idx, count, NULL))
 161                 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdires2");
 162 }
 163
 164 static void zfcp_qdio_irq_tasklet(struct tasklet_struct *tasklet)
 165 {
 166         struct zfcp_qdio *qdio = from_tasklet(qdio, tasklet, irq_tasklet);
 167         struct ccw_device *cdev = qdio->adapter->ccw_device;
 168         unsigned int start, error;
 169         int completed;
 170
 171         if (atomic_read(&qdio->req_q_free) < QDIO_MAX_BUFFERS_PER_Q)
 172                 tasklet_schedule(&qdio->request_tasklet);
 173
 174         /* Check the Response Queue: */
 175         completed = qdio_inspect_queue(cdev, 0, true, &start, &error);
 176         if (completed < 0)
 177                 return;
 178         if (completed > 0)
 179                 zfcp_qdio_int_resp(cdev, error, 0, start, completed,
 180                                    (unsigned long) qdio);
 181
 182         if (qdio_start_irq(cdev))
 183                 /* More work pending: */
 184                 tasklet_schedule(&qdio->irq_tasklet);
 185 }
 186
 187 static void zfcp_qdio_poll(struct ccw_device *cdev, unsigned long data)
 188 {
 189         struct zfcp_qdio *qdio = (struct zfcp_qdio *) data;
 190
 191         tasklet_schedule(&qdio->irq_tasklet);
 192 }
 193
 194 static struct qdio_buffer_element *
 195 zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
 196 {
 197         struct qdio_buffer_element *sbale;
 198
 199         /* set last entry flag in current SBALE of current SBAL */
 200         sbale = zfcp_qdio_sbale_curr(qdio, q_req);
 201         sbale->eflags |= SBAL_EFLAGS_LAST_ENTRY;
 202
 203         /* don't exceed last allowed SBAL */
 204         if (q_req->sbal_last == q_req->sbal_limit)
 205                 return NULL;
 206
 207         /* set chaining flag in first SBALE of current SBAL */
 208         sbale = zfcp_qdio_sbale_req(qdio, q_req);
 209         sbale->sflags |= SBAL_SFLAGS0_MORE_SBALS;
 210
 211         /* calculate index of next SBAL */
 212         q_req->sbal_last++;
 213         q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q;
 214
 215         /* keep this requests number of SBALs up-to-date */
 216         q_req->sbal_number++;
 217         BUG_ON(q_req->sbal_number > ZFCP_QDIO_MAX_SBALS_PER_REQ);
 218
 219         /* start at first SBALE of new SBAL */
 220         q_req->sbale_curr = 0;
 221
 222         /* set storage-block type for new SBAL */
 223         sbale = zfcp_qdio_sbale_curr(qdio, q_req);
 224         sbale->sflags |= q_req->sbtype;
 225
 226         return sbale;
 227 }
 228
 229 static struct qdio_buffer_element *
 230 zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
 231 {
 232         if (q_req->sbale_curr == qdio->max_sbale_per_sbal - 1)
 233                 return zfcp_qdio_sbal_chain(qdio, q_req);
 234         q_req->sbale_curr++;
 235         return zfcp_qdio_sbale_curr(qdio, q_req);
 236 }
 237
 238 /**
 239  * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
 240  * @qdio: pointer to struct zfcp_qdio
 241  * @q_req: pointer to struct zfcp_qdio_req
 242  * @sg: scatter-gather list
 243  * Returns: zero or -EINVAL on error
 244  */
 245 int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,
 246                             struct scatterlist *sg)
 247 {
 248         struct qdio_buffer_element *sbale;
 249
 250         /* set storage-block type for this request */
 251         sbale = zfcp_qdio_sbale_req(qdio, q_req);
 252         sbale->sflags |= q_req->sbtype;
 253
 254         for (; sg; sg = sg_next(sg)) {
 255                 sbale = zfcp_qdio_sbale_next(qdio, q_req);
 256                 if (!sbale) {
 257                         atomic_inc(&qdio->req_q_full);
 258                         zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,
 259                                              q_req->sbal_number);
 260                         return -EINVAL;
 261                 }
 262                 sbale->addr = sg_phys(sg);
 263                 sbale->length = sg->length;
 264         }
 265         return 0;
 266 }
 267
 268 static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio)
 269 {
 270         if (atomic_read(&qdio->req_q_free) ||
 271             !(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
 272                 return 1;
 273         return 0;
 274 }
 275
 276 /**
 277  * zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary
 278  * @qdio: pointer to struct zfcp_qdio
 279  *
 280  * The req_q_lock must be held by the caller of this function, and
 281  * this function may only be called from process context; it will
 282  * sleep when waiting for a free sbal.
 283  *
 284  * Returns: 0 on success, -EIO if there is no free sbal after waiting.
 285  */
 286 int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio)
 287 {
 288         long ret;
 289
 290         ret = wait_event_interruptible_lock_irq_timeout(qdio->req_q_wq,
 291                        zfcp_qdio_sbal_check(qdio), qdio->req_q_lock, 5 * HZ);
 292
 293         if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
 294                 return -EIO;
 295
 296         if (ret > 0)
 297                 return 0;
 298
 299         if (!ret) {
 300                 atomic_inc(&qdio->req_q_full);
 301                 /* assume hanging outbound queue, try queue recovery */
 302                 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1");
 303         }
 304
 305         return -EIO;
 306 }
 307
 308 /**
 309  * zfcp_qdio_send - send req to QDIO
 310  * @qdio: pointer to struct zfcp_qdio
 311  * @q_req: pointer to struct zfcp_qdio_req
 312  * Returns: 0 on success, error otherwise
 313  */
 314 int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
 315 {
 316         int retval;
 317         u8 sbal_number = q_req->sbal_number;
 318
 319         /*
 320          * This should actually be a spin_lock_bh(stat_lock), to protect against
 321          * Request Queue completion processing in tasklet context.
 322          * But we can't do so (and are safe), as we always get called with IRQs
 323          * disabled by spin_lock_irq[save](req_q_lock).
 324          */
 325         lockdep_assert_irqs_disabled();
 326         spin_lock(&qdio->stat_lock);
 327         zfcp_qdio_account(qdio);
 328         spin_unlock(&qdio->stat_lock);
 329
 330         atomic_sub(sbal_number, &qdio->req_q_free);
 331
 332         retval = do_QDIO(qdio->adapter->ccw_device, QDIO_FLAG_SYNC_OUTPUT, 0,
 333                          q_req->sbal_first, sbal_number, NULL);
 334
 335         if (unlikely(retval)) {
 336                 /* Failed to submit the IO, roll back our modifications. */
 337                 atomic_add(sbal_number, &qdio->req_q_free);
 338                 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,
 339                                      sbal_number);
 340                 return retval;
 341         }
 342
 343         if (atomic_read(&qdio->req_q_free) <= 2 * ZFCP_QDIO_MAX_SBALS_PER_REQ)
 344                 tasklet_schedule(&qdio->request_tasklet);
 345         else
 346                 timer_reduce(&qdio->request_timer,
 347                              jiffies + msecs_to_jiffies(ZFCP_QDIO_REQUEST_SCAN_MSECS));
 348
 349         /* account for transferred buffers */
 350         qdio->req_q_idx += sbal_number;
 351         qdio->req_q_idx %= QDIO_MAX_BUFFERS_PER_Q;
 352
 353         return 0;
 354 }
 355
 356 /**
 357  * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data
 358  * @qdio: pointer to struct zfcp_qdio
 359  * Returns: -ENOMEM on memory allocation error or return value from
 360  *          qdio_allocate
 361  */
 362 static int zfcp_qdio_allocate(struct zfcp_qdio *qdio)
 363 {
 364         int ret;
 365
 366         ret = qdio_alloc_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
 367         if (ret)
 368                 return -ENOMEM;
 369
 370         ret = qdio_alloc_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
 371         if (ret)
 372                 goto free_req_q;
 373
 374         init_waitqueue_head(&qdio->req_q_wq);
 375
 376         ret = qdio_allocate(qdio->adapter->ccw_device, 1, 1);
 377         if (ret)
 378                 goto free_res_q;
 379
 380         return 0;
 381
 382 free_res_q:
 383         qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
 384 free_req_q:
 385         qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
 386         return ret;
 387 }
 388
 389 /**
 390  * zfcp_close_qdio - close qdio queues for an adapter
 391  * @qdio: pointer to structure zfcp_qdio
 392  */
 393 void zfcp_qdio_close(struct zfcp_qdio *qdio)
 394 {
 395         struct zfcp_adapter *adapter = qdio->adapter;
 396         int idx, count;
 397
 398         if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
 399                 return;
 400
 401         /* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */
 402         spin_lock_irq(&qdio->req_q_lock);
 403         atomic_andnot(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status);
 404         spin_unlock_irq(&qdio->req_q_lock);
 405
 406         wake_up(&qdio->req_q_wq);
 407
 408         tasklet_disable(&qdio->irq_tasklet);
 409         tasklet_disable(&qdio->request_tasklet);
 410         del_timer_sync(&qdio->request_timer);
 411         qdio_stop_irq(adapter->ccw_device);
 412         qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR);
 413
 414         /* cleanup used outbound sbals */
 415         count = atomic_read(&qdio->req_q_free);
 416         if (count < QDIO_MAX_BUFFERS_PER_Q) {
 417                 idx = (qdio->req_q_idx + count) % QDIO_MAX_BUFFERS_PER_Q;
 418                 count = QDIO_MAX_BUFFERS_PER_Q - count;
 419                 zfcp_qdio_zero_sbals(qdio->req_q, idx, count);
 420         }
 421         qdio->req_q_idx = 0;
 422         atomic_set(&qdio->req_q_free, 0);
 423 }
 424
 425 void zfcp_qdio_shost_update(struct zfcp_adapter *const adapter,
 426                             const struct zfcp_qdio *const qdio)
 427 {
 428         struct Scsi_Host *const shost = adapter->scsi_host;
 429
 430         if (shost == NULL)
 431                 return;
 432
 433         shost->sg_tablesize = qdio->max_sbale_per_req;
 434         shost->max_sectors = qdio->max_sbale_per_req * 8;
 435 }
 436
 437 /**
 438  * zfcp_qdio_open - prepare and initialize response queue
 439  * @qdio: pointer to struct zfcp_qdio
 440  * Returns: 0 on success, otherwise -EIO
 441  */
 442 int zfcp_qdio_open(struct zfcp_qdio *qdio)
 443 {
 444         struct qdio_buffer **input_sbals[1] = {qdio->res_q};
 445         struct qdio_buffer **output_sbals[1] = {qdio->req_q};
 446         struct qdio_buffer_element *sbale;
 447         struct qdio_initialize init_data = {0};
 448         struct zfcp_adapter *adapter = qdio->adapter;
 449         struct ccw_device *cdev = adapter->ccw_device;
 450         struct qdio_ssqd_desc ssqd;
 451         int cc;
 452
 453         if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)
 454                 return -EIO;
 455
 456         atomic_andnot(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,
 457                           &qdio->adapter->status);
 458
 459         init_data.q_format = QDIO_ZFCP_QFMT;
 460         init_data.qib_rflags = QIB_RFLAGS_ENABLE_DATA_DIV;
 461         if (enable_multibuffer)
 462                 init_data.qdr_ac |= QDR_AC_MULTI_BUFFER_ENABLE;
 463         init_data.no_input_qs = 1;
 464         init_data.no_output_qs = 1;
 465         init_data.input_handler = zfcp_qdio_int_resp;
 466         init_data.output_handler = zfcp_qdio_int_req;
 467         init_data.irq_poll = zfcp_qdio_poll;
 468         init_data.int_parm = (unsigned long) qdio;
 469         init_data.input_sbal_addr_array = input_sbals;
 470         init_data.output_sbal_addr_array = output_sbals;
 471
 472         if (qdio_establish(cdev, &init_data))
 473                 goto failed_establish;
 474
 475         if (qdio_get_ssqd_desc(cdev, &ssqd))
 476                 goto failed_qdio;
 477
 478         if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED)
 479                 atomic_or(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED,
 480                                 &qdio->adapter->status);
 481
 482         if (ssqd.qdioac2 & CHSC_AC2_MULTI_BUFFER_ENABLED) {
 483                 atomic_or(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);
 484                 qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER;
 485         } else {
 486                 atomic_andnot(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);
 487                 qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER - 1;
 488         }
 489
 490         qdio->max_sbale_per_req =
 491                 ZFCP_QDIO_MAX_SBALS_PER_REQ * qdio->max_sbale_per_sbal
 492                 - 2;
 493         if (qdio_activate(cdev))
 494                 goto failed_qdio;
 495
 496         for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) {
 497                 sbale = &(qdio->res_q[cc]->element[0]);
 498                 sbale->length = 0;
 499                 sbale->eflags = SBAL_EFLAGS_LAST_ENTRY;
 500                 sbale->sflags = 0;
 501                 sbale->addr = 0;
 502         }
 503
 504         if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0, QDIO_MAX_BUFFERS_PER_Q,
 505                     NULL))
 506                 goto failed_qdio;
 507
 508         /* set index of first available SBALS / number of available SBALS */
 509         qdio->req_q_idx = 0;
 510         atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q);
 511         atomic_or(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status);
 512
 513         /* Enable processing for Request Queue completions: */
 514         tasklet_enable(&qdio->request_tasklet);
 515         /* Enable processing for QDIO interrupts: */
 516         tasklet_enable(&qdio->irq_tasklet);
 517         /* This results in a qdio_start_irq(): */
 518         tasklet_schedule(&qdio->irq_tasklet);
 519
 520         zfcp_qdio_shost_update(adapter, qdio);
 521
 522         return 0;
 523
 524 failed_qdio:
 525         qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
 526 failed_establish:
 527         dev_err(&cdev->dev,
 528                 "Setting up the QDIO connection to the FCP adapter failed\n");
 529         return -EIO;
 530 }
 531
 532 void zfcp_qdio_destroy(struct zfcp_qdio *qdio)
 533 {
 534         if (!qdio)
 535                 return;
 536
 537         tasklet_kill(&qdio->irq_tasklet);
 538         tasklet_kill(&qdio->request_tasklet);
 539
 540         if (qdio->adapter->ccw_device)
 541                 qdio_free(qdio->adapter->ccw_device);
 542
 543         qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);
 544         qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);
 545         kfree(qdio);
 546 }
 547
 548 int zfcp_qdio_setup(struct zfcp_adapter *adapter)
 549 {
 550         struct zfcp_qdio *qdio;
 551
 552         qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL);
 553         if (!qdio)
 554                 return -ENOMEM;
 555
 556         qdio->adapter = adapter;
 557
 558         if (zfcp_qdio_allocate(qdio)) {
 559                 kfree(qdio);
 560                 return -ENOMEM;
 561         }
 562
 563         spin_lock_init(&qdio->req_q_lock);
 564         spin_lock_init(&qdio->stat_lock);
 565         timer_setup(&qdio->request_timer, zfcp_qdio_request_timer, 0);
 566         tasklet_setup(&qdio->irq_tasklet, zfcp_qdio_irq_tasklet);
 567         tasklet_setup(&qdio->request_tasklet, zfcp_qdio_request_tasklet);
 568         tasklet_disable(&qdio->irq_tasklet);
 569         tasklet_disable(&qdio->request_tasklet);
 570
 571         adapter->qdio = qdio;
 572         return 0;
 573 }
 574
 575 /**
 576  * zfcp_qdio_siosl - Trigger logging in FCP channel
 577  * @adapter: The zfcp_adapter where to trigger logging
 578  *
 579  * Call the cio siosl function to trigger hardware logging.  This
 580  * wrapper function sets a flag to ensure hardware logging is only
 581  * triggered once before going through qdio shutdown.
 582  *
 583  * The triggers are always run from qdio tasklet context, so no
 584  * additional synchronization is necessary.
 585  */
 586 void zfcp_qdio_siosl(struct zfcp_adapter *adapter)
 587 {
 588         int rc;
 589
 590         if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED)
 591                 return;
 592
 593         rc = ccw_device_siosl(adapter->ccw_device);
 594         if (!rc)
 595                 atomic_or(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,
 596                                 &adapter->status);
 597 }