drivers/s390/cio/qdio_main.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Linux for s390 qdio support, buffer handling, qdio API and module support.
   4  *
   5  * Copyright IBM Corp. 2000, 2008
   6  * Author(s): Utz Bacher <utz.bacher@de.ibm.com>
   7  *            Jan Glauber <jang@linux.vnet.ibm.com>
   8  * 2.6 cio integration by Cornelia Huck <cornelia.huck@de.ibm.com>
   9  */
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/kernel.h>
  13 #include <linux/kmemleak.h>
  14 #include <linux/delay.h>
  15 #include <linux/gfp.h>
  16 #include <linux/io.h>
  17 #include <linux/atomic.h>
  18 #include <asm/debug.h>
  19 #include <asm/qdio.h>
  20 #include <asm/ipl.h>
  21
  22 #include "cio.h"
  23 #include "css.h"
  24 #include "device.h"
  25 #include "qdio.h"
  26 #include "qdio_debug.h"
  27
  28 MODULE_AUTHOR("Utz Bacher <utz.bacher@de.ibm.com>,"\
  29         "Jan Glauber <jang@linux.vnet.ibm.com>");
  30 MODULE_DESCRIPTION("QDIO base support");
  31 MODULE_LICENSE("GPL");
  32
  33 static inline int do_siga_sync(unsigned long schid,
  34                                unsigned long out_mask, unsigned long in_mask,
  35                                unsigned int fc)
  36 {
  37         int cc;
  38
  39         asm volatile(
  40                 "       lgr     0,%[fc]\n"
  41                 "       lgr     1,%[schid]\n"
  42                 "       lgr     2,%[out]\n"
  43                 "       lgr     3,%[in]\n"
  44                 "       siga    0\n"
  45                 "       ipm     %[cc]\n"
  46                 "       srl     %[cc],28\n"
  47                 : [cc] "=&d" (cc)
  48                 : [fc] "d" (fc), [schid] "d" (schid),
  49                   [out] "d" (out_mask), [in] "d" (in_mask)
  50                 : "cc", "0", "1", "2", "3");
  51         return cc;
  52 }
  53
  54 static inline int do_siga_input(unsigned long schid, unsigned long mask,
  55                                 unsigned long fc)
  56 {
  57         int cc;
  58
  59         asm volatile(
  60                 "       lgr     0,%[fc]\n"
  61                 "       lgr     1,%[schid]\n"
  62                 "       lgr     2,%[mask]\n"
  63                 "       siga    0\n"
  64                 "       ipm     %[cc]\n"
  65                 "       srl     %[cc],28\n"
  66                 : [cc] "=&d" (cc)
  67                 : [fc] "d" (fc), [schid] "d" (schid), [mask] "d" (mask)
  68                 : "cc", "0", "1", "2");
  69         return cc;
  70 }
  71
  72 /**
  73  * do_siga_output - perform SIGA-w/wt function
  74  * @schid: subchannel id or in case of QEBSM the subchannel token
  75  * @mask: which output queues to process
  76  * @bb: busy bit indicator, set only if SIGA-w/wt could not access a buffer
  77  * @fc: function code to perform
  78  * @aob: asynchronous operation block
  79  *
  80  * Returns condition code.
  81  * Note: For IQDC unicast queues only the highest priority queue is processed.
  82  */
  83 static inline int do_siga_output(unsigned long schid, unsigned long mask,
  84                                  unsigned int *bb, unsigned long fc,
  85                                  unsigned long aob)
  86 {
  87         int cc;
  88
  89         asm volatile(
  90                 "       lgr     0,%[fc]\n"
  91                 "       lgr     1,%[schid]\n"
  92                 "       lgr     2,%[mask]\n"
  93                 "       lgr     3,%[aob]\n"
  94                 "       siga    0\n"
  95                 "       lgr     %[fc],0\n"
  96                 "       ipm     %[cc]\n"
  97                 "       srl     %[cc],28\n"
  98                 : [cc] "=&d" (cc), [fc] "+&d" (fc)
  99                 : [schid] "d" (schid), [mask] "d" (mask), [aob] "d" (aob)
 100                 : "cc", "0", "1", "2", "3");
 101         *bb = fc >> 31;
 102         return cc;
 103 }
 104
 105 /**
 106  * qdio_do_eqbs - extract buffer states for QEBSM
 107  * @q: queue to manipulate
 108  * @state: state of the extracted buffers
 109  * @start: buffer number to start at
 110  * @count: count of buffers to examine
 111  * @auto_ack: automatically acknowledge buffers
 112  *
 113  * Returns the number of successfully extracted equal buffer states.
 114  * Stops processing if a state is different from the last buffers state.
 115  */
 116 static int qdio_do_eqbs(struct qdio_q *q, unsigned char *state,
 117                         int start, int count, int auto_ack)
 118 {
 119         int tmp_count = count, tmp_start = start, nr = q->nr;
 120         unsigned int ccq = 0;
 121
 122         qperf_inc(q, eqbs);
 123
 124         if (!q->is_input_q)
 125                 nr += q->irq_ptr->nr_input_qs;
 126 again:
 127         ccq = do_eqbs(q->irq_ptr->sch_token, state, nr, &tmp_start, &tmp_count,
 128                       auto_ack);
 129
 130         switch (ccq) {
 131         case 0:
 132         case 32:
 133                 /* all done, or next buffer state different */
 134                 return count - tmp_count;
 135         case 96:
 136                 /* not all buffers processed */
 137                 qperf_inc(q, eqbs_partial);
 138                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "EQBS part:%02x",
 139                         tmp_count);
 140                 return count - tmp_count;
 141         case 97:
 142                 /* no buffer processed */
 143                 DBF_DEV_EVENT(DBF_WARN, q->irq_ptr, "EQBS again:%2d", ccq);
 144                 goto again;
 145         default:
 146                 DBF_ERROR("%4x ccq:%3d", SCH_NO(q), ccq);
 147                 DBF_ERROR("%4x EQBS ERROR", SCH_NO(q));
 148                 DBF_ERROR("%3d%3d%2d", count, tmp_count, nr);
 149                 q->handler(q->irq_ptr->cdev, QDIO_ERROR_GET_BUF_STATE, q->nr,
 150                            q->first_to_check, count, q->irq_ptr->int_parm);
 151                 return 0;
 152         }
 153 }
 154
 155 /**
 156  * qdio_do_sqbs - set buffer states for QEBSM
 157  * @q: queue to manipulate
 158  * @state: new state of the buffers
 159  * @start: first buffer number to change
 160  * @count: how many buffers to change
 161  *
 162  * Returns the number of successfully changed buffers.
 163  * Does retrying until the specified count of buffer states is set or an
 164  * error occurs.
 165  */
 166 static int qdio_do_sqbs(struct qdio_q *q, unsigned char state, int start,
 167                         int count)
 168 {
 169         unsigned int ccq = 0;
 170         int tmp_count = count, tmp_start = start;
 171         int nr = q->nr;
 172
 173         qperf_inc(q, sqbs);
 174
 175         if (!q->is_input_q)
 176                 nr += q->irq_ptr->nr_input_qs;
 177 again:
 178         ccq = do_sqbs(q->irq_ptr->sch_token, state, nr, &tmp_start, &tmp_count);
 179
 180         switch (ccq) {
 181         case 0:
 182         case 32:
 183                 /* all done, or active buffer adapter-owned */
 184                 WARN_ON_ONCE(tmp_count);
 185                 return count - tmp_count;
 186         case 96:
 187                 /* not all buffers processed */
 188                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "SQBS again:%2d", ccq);
 189                 qperf_inc(q, sqbs_partial);
 190                 goto again;
 191         default:
 192                 DBF_ERROR("%4x ccq:%3d", SCH_NO(q), ccq);
 193                 DBF_ERROR("%4x SQBS ERROR", SCH_NO(q));
 194                 DBF_ERROR("%3d%3d%2d", count, tmp_count, nr);
 195                 q->handler(q->irq_ptr->cdev, QDIO_ERROR_SET_BUF_STATE, q->nr,
 196                            q->first_to_check, count, q->irq_ptr->int_parm);
 197                 return 0;
 198         }
 199 }
 200
 201 /*
 202  * Returns number of examined buffers and their common state in *state.
 203  * Requested number of buffers-to-examine must be > 0.
 204  */
 205 static inline int get_buf_states(struct qdio_q *q, unsigned int bufnr,
 206                                  unsigned char *state, unsigned int count,
 207                                  int auto_ack)
 208 {
 209         unsigned char __state = 0;
 210         int i = 1;
 211
 212         if (is_qebsm(q))
 213                 return qdio_do_eqbs(q, state, bufnr, count, auto_ack);
 214
 215         /* get initial state: */
 216         __state = q->slsb.val[bufnr];
 217
 218         /* Bail out early if there is no work on the queue: */
 219         if (__state & SLSB_OWNER_CU)
 220                 goto out;
 221
 222         for (; i < count; i++) {
 223                 bufnr = next_buf(bufnr);
 224
 225                 /* stop if next state differs from initial state: */
 226                 if (q->slsb.val[bufnr] != __state)
 227                         break;
 228         }
 229
 230 out:
 231         *state = __state;
 232         return i;
 233 }
 234
 235 static inline int get_buf_state(struct qdio_q *q, unsigned int bufnr,
 236                                 unsigned char *state, int auto_ack)
 237 {
 238         return get_buf_states(q, bufnr, state, 1, auto_ack);
 239 }
 240
 241 /* wrap-around safe setting of slsb states, returns number of changed buffers */
 242 static inline int set_buf_states(struct qdio_q *q, int bufnr,
 243                                  unsigned char state, int count)
 244 {
 245         int i;
 246
 247         if (is_qebsm(q))
 248                 return qdio_do_sqbs(q, state, bufnr, count);
 249
 250         /* Ensure that all preceding changes to the SBALs are visible: */
 251         mb();
 252
 253         for (i = 0; i < count; i++) {
 254                 WRITE_ONCE(q->slsb.val[bufnr], state);
 255                 bufnr = next_buf(bufnr);
 256         }
 257
 258         /* Make our SLSB changes visible: */
 259         mb();
 260
 261         return count;
 262 }
 263
 264 static inline int set_buf_state(struct qdio_q *q, int bufnr,
 265                                 unsigned char state)
 266 {
 267         return set_buf_states(q, bufnr, state, 1);
 268 }
 269
 270 /* set slsb states to initial state */
 271 static void qdio_init_buf_states(struct qdio_irq *irq_ptr)
 272 {
 273         struct qdio_q *q;
 274         int i;
 275
 276         for_each_input_queue(irq_ptr, q, i)
 277                 set_buf_states(q, 0, SLSB_P_INPUT_NOT_INIT,
 278                                QDIO_MAX_BUFFERS_PER_Q);
 279         for_each_output_queue(irq_ptr, q, i)
 280                 set_buf_states(q, 0, SLSB_P_OUTPUT_NOT_INIT,
 281                                QDIO_MAX_BUFFERS_PER_Q);
 282 }
 283
 284 static inline int qdio_siga_sync(struct qdio_q *q, unsigned int output,
 285                           unsigned int input)
 286 {
 287         unsigned long schid = *((u32 *) &q->irq_ptr->schid);
 288         unsigned int fc = QDIO_SIGA_SYNC;
 289         int cc;
 290
 291         DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-s:%1d", q->nr);
 292         qperf_inc(q, siga_sync);
 293
 294         if (is_qebsm(q)) {
 295                 schid = q->irq_ptr->sch_token;
 296                 fc |= QDIO_SIGA_QEBSM_FLAG;
 297         }
 298
 299         cc = do_siga_sync(schid, output, input, fc);
 300         if (unlikely(cc))
 301                 DBF_ERROR("%4x SIGA-S:%2d", SCH_NO(q), cc);
 302         return (cc) ? -EIO : 0;
 303 }
 304
 305 static inline int qdio_sync_input_queue(struct qdio_q *q)
 306 {
 307         return qdio_siga_sync(q, 0, q->mask);
 308 }
 309
 310 static inline int qdio_sync_output_queue(struct qdio_q *q)
 311 {
 312         return qdio_siga_sync(q, q->mask, 0);
 313 }
 314
 315 static inline int qdio_siga_sync_q(struct qdio_q *q)
 316 {
 317         if (q->is_input_q)
 318                 return qdio_sync_input_queue(q);
 319         else
 320                 return qdio_sync_output_queue(q);
 321 }
 322
 323 static int qdio_siga_output(struct qdio_q *q, unsigned int count,
 324                             unsigned int *busy_bit, unsigned long aob)
 325 {
 326         unsigned long schid = *((u32 *) &q->irq_ptr->schid);
 327         unsigned int fc = QDIO_SIGA_WRITE;
 328         u64 start_time = 0;
 329         int retries = 0, cc;
 330
 331         if (queue_type(q) == QDIO_IQDIO_QFMT && !multicast_outbound(q)) {
 332                 if (count > 1)
 333                         fc = QDIO_SIGA_WRITEM;
 334                 else if (aob)
 335                         fc = QDIO_SIGA_WRITEQ;
 336         }
 337
 338         if (is_qebsm(q)) {
 339                 schid = q->irq_ptr->sch_token;
 340                 fc |= QDIO_SIGA_QEBSM_FLAG;
 341         }
 342 again:
 343         cc = do_siga_output(schid, q->mask, busy_bit, fc, aob);
 344
 345         /* hipersocket busy condition */
 346         if (unlikely(*busy_bit)) {
 347                 retries++;
 348
 349                 if (!start_time) {
 350                         start_time = get_tod_clock_fast();
 351                         goto again;
 352                 }
 353                 if (get_tod_clock_fast() - start_time < QDIO_BUSY_BIT_PATIENCE)
 354                         goto again;
 355         }
 356         if (retries) {
 357                 DBF_DEV_EVENT(DBF_WARN, q->irq_ptr,
 358                               "%4x cc2 BB1:%1d", SCH_NO(q), q->nr);
 359                 DBF_DEV_EVENT(DBF_WARN, q->irq_ptr, "count:%u", retries);
 360         }
 361         return cc;
 362 }
 363
 364 static inline int qdio_siga_input(struct qdio_q *q)
 365 {
 366         unsigned long schid = *((u32 *) &q->irq_ptr->schid);
 367         unsigned int fc = QDIO_SIGA_READ;
 368         int cc;
 369
 370         DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-r:%1d", q->nr);
 371         qperf_inc(q, siga_read);
 372
 373         if (is_qebsm(q)) {
 374                 schid = q->irq_ptr->sch_token;
 375                 fc |= QDIO_SIGA_QEBSM_FLAG;
 376         }
 377
 378         cc = do_siga_input(schid, q->mask, fc);
 379         if (unlikely(cc))
 380                 DBF_ERROR("%4x SIGA-R:%2d", SCH_NO(q), cc);
 381         return (cc) ? -EIO : 0;
 382 }
 383
 384 int debug_get_buf_state(struct qdio_q *q, unsigned int bufnr,
 385                         unsigned char *state)
 386 {
 387         if (qdio_need_siga_sync(q->irq_ptr))
 388                 qdio_siga_sync_q(q);
 389         return get_buf_state(q, bufnr, state, 0);
 390 }
 391
 392 static inline void qdio_stop_polling(struct qdio_q *q)
 393 {
 394         if (!q->u.in.batch_count)
 395                 return;
 396
 397         qperf_inc(q, stop_polling);
 398
 399         /* show the card that we are not polling anymore */
 400         set_buf_states(q, q->u.in.batch_start, SLSB_P_INPUT_NOT_INIT,
 401                        q->u.in.batch_count);
 402         q->u.in.batch_count = 0;
 403 }
 404
 405 static inline void account_sbals(struct qdio_q *q, unsigned int count)
 406 {
 407         q->q_stats.nr_sbal_total += count;
 408         q->q_stats.nr_sbals[ilog2(count)]++;
 409 }
 410
 411 static void process_buffer_error(struct qdio_q *q, unsigned int start,
 412                                  int count)
 413 {
 414         /* special handling for no target buffer empty */
 415         if (queue_type(q) == QDIO_IQDIO_QFMT && !q->is_input_q &&
 416             q->sbal[start]->element[15].sflags == 0x10) {
 417                 qperf_inc(q, target_full);
 418                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "OUTFULL FTC:%02x", start);
 419                 return;
 420         }
 421
 422         DBF_ERROR("%4x BUF ERROR", SCH_NO(q));
 423         DBF_ERROR((q->is_input_q) ? "IN:%2d" : "OUT:%2d", q->nr);
 424         DBF_ERROR("FTC:%3d C:%3d", start, count);
 425         DBF_ERROR("F14:%2x F15:%2x",
 426                   q->sbal[start]->element[14].sflags,
 427                   q->sbal[start]->element[15].sflags);
 428 }
 429
 430 static inline void inbound_handle_work(struct qdio_q *q, unsigned int start,
 431                                        int count, bool auto_ack)
 432 {
 433         /* ACK the newest SBAL: */
 434         if (!auto_ack)
 435                 set_buf_state(q, add_buf(start, count - 1), SLSB_P_INPUT_ACK);
 436
 437         if (!q->u.in.batch_count)
 438                 q->u.in.batch_start = start;
 439         q->u.in.batch_count += count;
 440 }
 441
 442 static int get_inbound_buffer_frontier(struct qdio_q *q, unsigned int start,
 443                                        unsigned int *error)
 444 {
 445         unsigned char state = 0;
 446         int count;
 447
 448         q->timestamp = get_tod_clock_fast();
 449
 450         count = atomic_read(&q->nr_buf_used);
 451         if (!count)
 452                 return 0;
 453
 454         if (qdio_need_siga_sync(q->irq_ptr))
 455                 qdio_sync_input_queue(q);
 456
 457         count = get_buf_states(q, start, &state, count, 1);
 458         if (!count)
 459                 return 0;
 460
 461         switch (state) {
 462         case SLSB_P_INPUT_PRIMED:
 463                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in prim:%1d %02x", q->nr,
 464                               count);
 465
 466                 inbound_handle_work(q, start, count, is_qebsm(q));
 467                 if (atomic_sub_return(count, &q->nr_buf_used) == 0)
 468                         qperf_inc(q, inbound_queue_full);
 469                 if (q->irq_ptr->perf_stat_enabled)
 470                         account_sbals(q, count);
 471                 return count;
 472         case SLSB_P_INPUT_ERROR:
 473                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in err:%1d %02x", q->nr,
 474                               count);
 475
 476                 *error = QDIO_ERROR_SLSB_STATE;
 477                 process_buffer_error(q, start, count);
 478                 inbound_handle_work(q, start, count, false);
 479                 if (atomic_sub_return(count, &q->nr_buf_used) == 0)
 480                         qperf_inc(q, inbound_queue_full);
 481                 if (q->irq_ptr->perf_stat_enabled)
 482                         account_sbals_error(q, count);
 483                 return count;
 484         case SLSB_CU_INPUT_EMPTY:
 485                 if (q->irq_ptr->perf_stat_enabled)
 486                         q->q_stats.nr_sbal_nop++;
 487                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in nop:%1d %#02x",
 488                               q->nr, start);
 489                 return 0;
 490         case SLSB_P_INPUT_NOT_INIT:
 491         case SLSB_P_INPUT_ACK:
 492                 /* We should never see this state, throw a WARN: */
 493         default:
 494                 dev_WARN_ONCE(&q->irq_ptr->cdev->dev, 1,
 495                               "found state %#x at index %u on queue %u\n",
 496                               state, start, q->nr);
 497                 return 0;
 498         }
 499 }
 500
 501 int qdio_inspect_input_queue(struct ccw_device *cdev, unsigned int nr,
 502                              unsigned int *bufnr, unsigned int *error)
 503 {
 504         struct qdio_irq *irq = cdev->private->qdio_data;
 505         unsigned int start;
 506         struct qdio_q *q;
 507         int count;
 508
 509         if (!irq)
 510                 return -ENODEV;
 511
 512         q = irq->input_qs[nr];
 513         start = q->first_to_check;
 514         *error = 0;
 515
 516         count = get_inbound_buffer_frontier(q, start, error);
 517         if (count == 0)
 518                 return 0;
 519
 520         *bufnr = start;
 521         q->first_to_check = add_buf(start, count);
 522         return count;
 523 }
 524 EXPORT_SYMBOL_GPL(qdio_inspect_input_queue);
 525
 526 static inline int qdio_inbound_q_done(struct qdio_q *q, unsigned int start)
 527 {
 528         unsigned char state = 0;
 529
 530         if (!atomic_read(&q->nr_buf_used))
 531                 return 1;
 532
 533         if (qdio_need_siga_sync(q->irq_ptr))
 534                 qdio_sync_input_queue(q);
 535         get_buf_state(q, start, &state, 0);
 536
 537         if (state == SLSB_P_INPUT_PRIMED || state == SLSB_P_INPUT_ERROR)
 538                 /* more work coming */
 539                 return 0;
 540
 541         return 1;
 542 }
 543
 544 static int get_outbound_buffer_frontier(struct qdio_q *q, unsigned int start,
 545                                         unsigned int *error)
 546 {
 547         unsigned char state = 0;
 548         int count;
 549
 550         q->timestamp = get_tod_clock_fast();
 551
 552         count = atomic_read(&q->nr_buf_used);
 553         if (!count)
 554                 return 0;
 555
 556         if (qdio_need_siga_sync(q->irq_ptr))
 557                 qdio_sync_output_queue(q);
 558
 559         count = get_buf_states(q, start, &state, count, 0);
 560         if (!count)
 561                 return 0;
 562
 563         switch (state) {
 564         case SLSB_P_OUTPUT_PENDING:
 565                 *error = QDIO_ERROR_SLSB_PENDING;
 566                 fallthrough;
 567         case SLSB_P_OUTPUT_EMPTY:
 568                 /* the adapter got it */
 569                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr,
 570                         "out empty:%1d %02x", q->nr, count);
 571
 572                 atomic_sub(count, &q->nr_buf_used);
 573                 if (q->irq_ptr->perf_stat_enabled)
 574                         account_sbals(q, count);
 575                 return count;
 576         case SLSB_P_OUTPUT_ERROR:
 577                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out error:%1d %02x",
 578                               q->nr, count);
 579
 580                 *error = QDIO_ERROR_SLSB_STATE;
 581                 process_buffer_error(q, start, count);
 582                 atomic_sub(count, &q->nr_buf_used);
 583                 if (q->irq_ptr->perf_stat_enabled)
 584                         account_sbals_error(q, count);
 585                 return count;
 586         case SLSB_CU_OUTPUT_PRIMED:
 587                 /* the adapter has not fetched the output yet */
 588                 if (q->irq_ptr->perf_stat_enabled)
 589                         q->q_stats.nr_sbal_nop++;
 590                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out primed:%1d",
 591                               q->nr);
 592                 return 0;
 593         case SLSB_P_OUTPUT_HALTED:
 594                 return 0;
 595         case SLSB_P_OUTPUT_NOT_INIT:
 596                 /* We should never see this state, throw a WARN: */
 597         default:
 598                 dev_WARN_ONCE(&q->irq_ptr->cdev->dev, 1,
 599                               "found state %#x at index %u on queue %u\n",
 600                               state, start, q->nr);
 601                 return 0;
 602         }
 603 }
 604
 605 int qdio_inspect_output_queue(struct ccw_device *cdev, unsigned int nr,
 606                               unsigned int *bufnr, unsigned int *error)
 607 {
 608         struct qdio_irq *irq = cdev->private->qdio_data;
 609         unsigned int start;
 610         struct qdio_q *q;
 611         int count;
 612
 613         if (!irq)
 614                 return -ENODEV;
 615
 616         q = irq->output_qs[nr];
 617         start = q->first_to_check;
 618         *error = 0;
 619
 620         count = get_outbound_buffer_frontier(q, start, error);
 621         if (count == 0)
 622                 return 0;
 623
 624         *bufnr = start;
 625         q->first_to_check = add_buf(start, count);
 626         return count;
 627 }
 628 EXPORT_SYMBOL_GPL(qdio_inspect_output_queue);
 629
 630 static int qdio_kick_outbound_q(struct qdio_q *q, unsigned int count,
 631                                 unsigned long aob)
 632 {
 633         int retries = 0, cc;
 634         unsigned int busy_bit;
 635
 636         if (!qdio_need_siga_out(q->irq_ptr))
 637                 return 0;
 638
 639         DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w:%1d", q->nr);
 640 retry:
 641         qperf_inc(q, siga_write);
 642
 643         cc = qdio_siga_output(q, count, &busy_bit, aob);
 644         switch (cc) {
 645         case 0:
 646                 break;
 647         case 2:
 648                 if (busy_bit) {
 649                         while (++retries < QDIO_BUSY_BIT_RETRIES) {
 650                                 mdelay(QDIO_BUSY_BIT_RETRY_DELAY);
 651                                 goto retry;
 652                         }
 653                         DBF_ERROR("%4x cc2 BBC:%1d", SCH_NO(q), q->nr);
 654                         cc = -EBUSY;
 655                 } else {
 656                         DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w cc2:%1d", q->nr);
 657                         cc = -ENOBUFS;
 658                 }
 659                 break;
 660         case 1:
 661         case 3:
 662                 DBF_ERROR("%4x SIGA-W:%1d", SCH_NO(q), cc);
 663                 cc = -EIO;
 664                 break;
 665         }
 666         if (retries) {
 667                 DBF_ERROR("%4x cc2 BB2:%1d", SCH_NO(q), q->nr);
 668                 DBF_ERROR("count:%u", retries);
 669         }
 670         return cc;
 671 }
 672
 673 static inline void qdio_set_state(struct qdio_irq *irq_ptr,
 674                                   enum qdio_irq_states state)
 675 {
 676         DBF_DEV_EVENT(DBF_INFO, irq_ptr, "newstate: %1d", state);
 677
 678         irq_ptr->state = state;
 679         mb();
 680 }
 681
 682 static void qdio_irq_check_sense(struct qdio_irq *irq_ptr, struct irb *irb)
 683 {
 684         if (irb->esw.esw0.erw.cons) {
 685                 DBF_ERROR("%4x sense:", irq_ptr->schid.sch_no);
 686                 DBF_ERROR_HEX(irb, 64);
 687                 DBF_ERROR_HEX(irb->ecw, 64);
 688         }
 689 }
 690
 691 /* PCI interrupt handler */
 692 static void qdio_int_handler_pci(struct qdio_irq *irq_ptr)
 693 {
 694         if (unlikely(irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
 695                 return;
 696
 697         qdio_deliver_irq(irq_ptr);
 698         irq_ptr->last_data_irq_time = S390_lowcore.int_clock;
 699 }
 700
 701 static void qdio_handle_activate_check(struct qdio_irq *irq_ptr,
 702                                        unsigned long intparm, int cstat,
 703                                        int dstat)
 704 {
 705         unsigned int first_to_check = 0;
 706
 707         DBF_ERROR("%4x ACT CHECK", irq_ptr->schid.sch_no);
 708         DBF_ERROR("intp :%lx", intparm);
 709         DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
 710
 711         /* zfcp wants this: */
 712         if (irq_ptr->nr_input_qs)
 713                 first_to_check = irq_ptr->input_qs[0]->first_to_check;
 714
 715         irq_ptr->error_handler(irq_ptr->cdev, QDIO_ERROR_ACTIVATE, 0,
 716                                first_to_check, 0, irq_ptr->int_parm);
 717         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
 718         /*
 719          * In case of z/VM LGR (Live Guest Migration) QDIO recovery will happen.
 720          * Therefore we call the LGR detection function here.
 721          */
 722         lgr_info_log();
 723 }
 724
 725 static int qdio_establish_handle_irq(struct qdio_irq *irq_ptr, int cstat,
 726                                      int dstat, int dcc)
 727 {
 728         DBF_DEV_EVENT(DBF_INFO, irq_ptr, "qest irq");
 729
 730         if (cstat)
 731                 goto error;
 732         if (dstat & ~(DEV_STAT_DEV_END | DEV_STAT_CHN_END))
 733                 goto error;
 734         if (dcc == 1)
 735                 return -EAGAIN;
 736         if (!(dstat & DEV_STAT_DEV_END))
 737                 goto error;
 738         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ESTABLISHED);
 739         return 0;
 740
 741 error:
 742         DBF_ERROR("%4x EQ:error", irq_ptr->schid.sch_no);
 743         DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
 744         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
 745         return -EIO;
 746 }
 747
 748 /* qdio interrupt handler */
 749 void qdio_int_handler(struct ccw_device *cdev, unsigned long intparm,
 750                       struct irb *irb)
 751 {
 752         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
 753         struct subchannel_id schid;
 754         int cstat, dstat, rc, dcc;
 755
 756         if (!intparm || !irq_ptr) {
 757                 ccw_device_get_schid(cdev, &schid);
 758                 DBF_ERROR("qint:%4x", schid.sch_no);
 759                 return;
 760         }
 761
 762         if (irq_ptr->perf_stat_enabled)
 763                 irq_ptr->perf_stat.qdio_int++;
 764
 765         if (IS_ERR(irb)) {
 766                 DBF_ERROR("%4x IO error", irq_ptr->schid.sch_no);
 767                 qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
 768                 wake_up(&cdev->private->wait_q);
 769                 return;
 770         }
 771         qdio_irq_check_sense(irq_ptr, irb);
 772         cstat = irb->scsw.cmd.cstat;
 773         dstat = irb->scsw.cmd.dstat;
 774         dcc   = scsw_cmd_is_valid_cc(&irb->scsw) ? irb->scsw.cmd.cc : 0;
 775         rc    = 0;
 776
 777         switch (irq_ptr->state) {
 778         case QDIO_IRQ_STATE_INACTIVE:
 779                 rc = qdio_establish_handle_irq(irq_ptr, cstat, dstat, dcc);
 780                 break;
 781         case QDIO_IRQ_STATE_CLEANUP:
 782                 qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
 783                 break;
 784         case QDIO_IRQ_STATE_ESTABLISHED:
 785         case QDIO_IRQ_STATE_ACTIVE:
 786                 if (cstat & SCHN_STAT_PCI) {
 787                         qdio_int_handler_pci(irq_ptr);
 788                         return;
 789                 }
 790                 if (cstat || dstat)
 791                         qdio_handle_activate_check(irq_ptr, intparm, cstat,
 792                                                    dstat);
 793                 else if (dcc == 1)
 794                         rc = -EAGAIN;
 795                 break;
 796         case QDIO_IRQ_STATE_STOPPED:
 797                 break;
 798         default:
 799                 WARN_ON_ONCE(1);
 800         }
 801
 802         if (rc == -EAGAIN) {
 803                 DBF_DEV_EVENT(DBF_INFO, irq_ptr, "qint retry");
 804                 rc = ccw_device_start(cdev, irq_ptr->ccw, intparm, 0, 0);
 805                 if (!rc)
 806                         return;
 807                 DBF_ERROR("%4x RETRY ERR", irq_ptr->schid.sch_no);
 808                 DBF_ERROR("rc:%4x", rc);
 809                 qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
 810         }
 811
 812         wake_up(&cdev->private->wait_q);
 813 }
 814
 815 /**
 816  * qdio_get_ssqd_desc - get qdio subchannel description
 817  * @cdev: ccw device to get description for
 818  * @data: where to store the ssqd
 819  *
 820  * Returns 0 or an error code. The results of the chsc are stored in the
 821  * specified structure.
 822  */
 823 int qdio_get_ssqd_desc(struct ccw_device *cdev,
 824                        struct qdio_ssqd_desc *data)
 825 {
 826         struct subchannel_id schid;
 827
 828         if (!cdev || !cdev->private)
 829                 return -EINVAL;
 830
 831         ccw_device_get_schid(cdev, &schid);
 832         DBF_EVENT("get ssqd:%4x", schid.sch_no);
 833         return qdio_setup_get_ssqd(NULL, &schid, data);
 834 }
 835 EXPORT_SYMBOL_GPL(qdio_get_ssqd_desc);
 836
 837 static int qdio_cancel_ccw(struct qdio_irq *irq, int how)
 838 {
 839         struct ccw_device *cdev = irq->cdev;
 840         long timeout;
 841         int rc;
 842
 843         spin_lock_irq(get_ccwdev_lock(cdev));
 844         qdio_set_state(irq, QDIO_IRQ_STATE_CLEANUP);
 845         if (how & QDIO_FLAG_CLEANUP_USING_CLEAR)
 846                 rc = ccw_device_clear(cdev, QDIO_DOING_CLEANUP);
 847         else
 848                 /* default behaviour is halt */
 849                 rc = ccw_device_halt(cdev, QDIO_DOING_CLEANUP);
 850         spin_unlock_irq(get_ccwdev_lock(cdev));
 851         if (rc) {
 852                 DBF_ERROR("%4x SHUTD ERR", irq->schid.sch_no);
 853                 DBF_ERROR("rc:%4d", rc);
 854                 return rc;
 855         }
 856
 857         timeout = wait_event_interruptible_timeout(cdev->private->wait_q,
 858                                                    irq->state == QDIO_IRQ_STATE_INACTIVE ||
 859                                                    irq->state == QDIO_IRQ_STATE_ERR,
 860                                                    10 * HZ);
 861         if (timeout <= 0)
 862                 rc = (timeout == -ERESTARTSYS) ? -EINTR : -ETIME;
 863
 864         return rc;
 865 }
 866
 867 /**
 868  * qdio_shutdown - shut down a qdio subchannel
 869  * @cdev: associated ccw device
 870  * @how: use halt or clear to shutdown
 871  */
 872 int qdio_shutdown(struct ccw_device *cdev, int how)
 873 {
 874         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
 875         struct subchannel_id schid;
 876         int rc;
 877
 878         if (!irq_ptr)
 879                 return -ENODEV;
 880
 881         WARN_ON_ONCE(irqs_disabled());
 882         ccw_device_get_schid(cdev, &schid);
 883         DBF_EVENT("qshutdown:%4x", schid.sch_no);
 884
 885         mutex_lock(&irq_ptr->setup_mutex);
 886         /*
 887          * Subchannel was already shot down. We cannot prevent being called
 888          * twice since cio may trigger a shutdown asynchronously.
 889          */
 890         if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
 891                 mutex_unlock(&irq_ptr->setup_mutex);
 892                 return 0;
 893         }
 894
 895         /*
 896          * Indicate that the device is going down.
 897          */
 898         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
 899
 900         qdio_shutdown_debug_entries(irq_ptr);
 901
 902         rc = qdio_cancel_ccw(irq_ptr, how);
 903         qdio_shutdown_thinint(irq_ptr);
 904         qdio_shutdown_irq(irq_ptr);
 905
 906         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
 907         mutex_unlock(&irq_ptr->setup_mutex);
 908         if (rc)
 909                 return rc;
 910         return 0;
 911 }
 912 EXPORT_SYMBOL_GPL(qdio_shutdown);
 913
 914 /**
 915  * qdio_free - free data structures for a qdio subchannel
 916  * @cdev: associated ccw device
 917  */
 918 int qdio_free(struct ccw_device *cdev)
 919 {
 920         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
 921         struct subchannel_id schid;
 922
 923         if (!irq_ptr)
 924                 return -ENODEV;
 925
 926         ccw_device_get_schid(cdev, &schid);
 927         DBF_EVENT("qfree:%4x", schid.sch_no);
 928         DBF_DEV_EVENT(DBF_ERR, irq_ptr, "dbf abandoned");
 929         mutex_lock(&irq_ptr->setup_mutex);
 930
 931         irq_ptr->debug_area = NULL;
 932         cdev->private->qdio_data = NULL;
 933         mutex_unlock(&irq_ptr->setup_mutex);
 934
 935         qdio_free_queues(irq_ptr);
 936         free_page((unsigned long) irq_ptr->qdr);
 937         free_page(irq_ptr->chsc_page);
 938         kfree(irq_ptr->ccw);
 939         free_page((unsigned long) irq_ptr);
 940         return 0;
 941 }
 942 EXPORT_SYMBOL_GPL(qdio_free);
 943
 944 /**
 945  * qdio_allocate - allocate qdio queues and associated data
 946  * @cdev: associated ccw device
 947  * @no_input_qs: allocate this number of Input Queues
 948  * @no_output_qs: allocate this number of Output Queues
 949  */
 950 int qdio_allocate(struct ccw_device *cdev, unsigned int no_input_qs,
 951                   unsigned int no_output_qs)
 952 {
 953         struct subchannel_id schid;
 954         struct qdio_irq *irq_ptr;
 955         int rc = -ENOMEM;
 956
 957         ccw_device_get_schid(cdev, &schid);
 958         DBF_EVENT("qallocate:%4x", schid.sch_no);
 959
 960         if (no_input_qs > QDIO_MAX_QUEUES_PER_IRQ ||
 961             no_output_qs > QDIO_MAX_QUEUES_PER_IRQ)
 962                 return -EINVAL;
 963
 964         irq_ptr = (void *) get_zeroed_page(GFP_KERNEL);
 965         if (!irq_ptr)
 966                 return -ENOMEM;
 967
 968         irq_ptr->ccw = kmalloc(sizeof(*irq_ptr->ccw), GFP_KERNEL | GFP_DMA);
 969         if (!irq_ptr->ccw)
 970                 goto err_ccw;
 971
 972         /* kmemleak doesn't scan the page-allocated irq_ptr: */
 973         kmemleak_not_leak(irq_ptr->ccw);
 974
 975         irq_ptr->cdev = cdev;
 976         mutex_init(&irq_ptr->setup_mutex);
 977         if (qdio_allocate_dbf(irq_ptr))
 978                 goto err_dbf;
 979
 980         DBF_DEV_EVENT(DBF_ERR, irq_ptr, "alloc niq:%1u noq:%1u", no_input_qs,
 981                       no_output_qs);
 982
 983         /*
 984          * Allocate a page for the chsc calls in qdio_establish.
 985          * Must be pre-allocated since a zfcp recovery will call
 986          * qdio_establish. In case of low memory and swap on a zfcp disk
 987          * we may not be able to allocate memory otherwise.
 988          */
 989         irq_ptr->chsc_page = get_zeroed_page(GFP_KERNEL);
 990         if (!irq_ptr->chsc_page)
 991                 goto err_chsc;
 992
 993         /* qdr is used in ccw1.cda which is u32 */
 994         irq_ptr->qdr = (struct qdr *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 995         if (!irq_ptr->qdr)
 996                 goto err_qdr;
 997
 998         rc = qdio_allocate_qs(irq_ptr, no_input_qs, no_output_qs);
 999         if (rc)
1000                 goto err_queues;
1001
1002         cdev->private->qdio_data = irq_ptr;
1003         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
1004         return 0;
1005
1006 err_queues:
1007         free_page((unsigned long) irq_ptr->qdr);
1008 err_qdr:
1009         free_page(irq_ptr->chsc_page);
1010 err_chsc:
1011 err_dbf:
1012         kfree(irq_ptr->ccw);
1013 err_ccw:
1014         free_page((unsigned long) irq_ptr);
1015         return rc;
1016 }
1017 EXPORT_SYMBOL_GPL(qdio_allocate);
1018
1019 static void qdio_trace_init_data(struct qdio_irq *irq,
1020                                  struct qdio_initialize *data)
1021 {
1022         DBF_DEV_EVENT(DBF_ERR, irq, "qfmt:%1u", data->q_format);
1023         DBF_DEV_EVENT(DBF_ERR, irq, "qpff%4x", data->qib_param_field_format);
1024         DBF_DEV_HEX(irq, &data->qib_param_field, sizeof(void *), DBF_ERR);
1025         DBF_DEV_EVENT(DBF_ERR, irq, "niq:%1u noq:%1u", data->no_input_qs,
1026                       data->no_output_qs);
1027         DBF_DEV_HEX(irq, &data->input_handler, sizeof(void *), DBF_ERR);
1028         DBF_DEV_HEX(irq, &data->output_handler, sizeof(void *), DBF_ERR);
1029         DBF_DEV_HEX(irq, &data->int_parm, sizeof(long), DBF_ERR);
1030         DBF_DEV_HEX(irq, &data->input_sbal_addr_array, sizeof(void *), DBF_ERR);
1031         DBF_DEV_HEX(irq, &data->output_sbal_addr_array, sizeof(void *),
1032                     DBF_ERR);
1033 }
1034
1035 /**
1036  * qdio_establish - establish queues on a qdio subchannel
1037  * @cdev: associated ccw device
1038  * @init_data: initialization data
1039  */
1040 int qdio_establish(struct ccw_device *cdev,
1041                    struct qdio_initialize *init_data)
1042 {
1043         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1044         struct subchannel_id schid;
1045         struct ciw *ciw;
1046         long timeout;
1047         int rc;
1048
1049         ccw_device_get_schid(cdev, &schid);
1050         DBF_EVENT("qestablish:%4x", schid.sch_no);
1051
1052         if (!irq_ptr)
1053                 return -ENODEV;
1054
1055         if (init_data->no_input_qs > irq_ptr->max_input_qs ||
1056             init_data->no_output_qs > irq_ptr->max_output_qs)
1057                 return -EINVAL;
1058
1059         /* Needed as error_handler: */
1060         if (!init_data->input_handler)
1061                 return -EINVAL;
1062
1063         if (init_data->no_output_qs && !init_data->output_handler)
1064                 return -EINVAL;
1065
1066         if (!init_data->input_sbal_addr_array ||
1067             !init_data->output_sbal_addr_array)
1068                 return -EINVAL;
1069
1070         if (!init_data->irq_poll)
1071                 return -EINVAL;
1072
1073         ciw = ccw_device_get_ciw(cdev, CIW_TYPE_EQUEUE);
1074         if (!ciw) {
1075                 DBF_ERROR("%4x NO EQ", schid.sch_no);
1076                 return -EIO;
1077         }
1078
1079         mutex_lock(&irq_ptr->setup_mutex);
1080         qdio_trace_init_data(irq_ptr, init_data);
1081         qdio_setup_irq(irq_ptr, init_data);
1082
1083         rc = qdio_establish_thinint(irq_ptr);
1084         if (rc)
1085                 goto err_thinint;
1086
1087         /* establish q */
1088         irq_ptr->ccw->cmd_code = ciw->cmd;
1089         irq_ptr->ccw->flags = CCW_FLAG_SLI;
1090         irq_ptr->ccw->count = ciw->count;
1091         irq_ptr->ccw->cda = (u32) virt_to_phys(irq_ptr->qdr);
1092
1093         spin_lock_irq(get_ccwdev_lock(cdev));
1094         ccw_device_set_options_mask(cdev, 0);
1095
1096         rc = ccw_device_start(cdev, irq_ptr->ccw, QDIO_DOING_ESTABLISH, 0, 0);
1097         spin_unlock_irq(get_ccwdev_lock(cdev));
1098         if (rc) {
1099                 DBF_ERROR("%4x est IO ERR", irq_ptr->schid.sch_no);
1100                 DBF_ERROR("rc:%4x", rc);
1101                 goto err_ccw_start;
1102         }
1103
1104         timeout = wait_event_interruptible_timeout(cdev->private->wait_q,
1105                                                    irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED ||
1106                                                    irq_ptr->state == QDIO_IRQ_STATE_ERR, HZ);
1107         if (timeout <= 0) {
1108                 rc = (timeout == -ERESTARTSYS) ? -EINTR : -ETIME;
1109                 goto err_ccw_timeout;
1110         }
1111
1112         if (irq_ptr->state != QDIO_IRQ_STATE_ESTABLISHED) {
1113                 rc = -EIO;
1114                 goto err_ccw_error;
1115         }
1116
1117         qdio_setup_ssqd_info(irq_ptr);
1118
1119         /* qebsm is now setup if available, initialize buffer states */
1120         qdio_init_buf_states(irq_ptr);
1121
1122         mutex_unlock(&irq_ptr->setup_mutex);
1123         qdio_print_subchannel_info(irq_ptr);
1124         qdio_setup_debug_entries(irq_ptr);
1125         return 0;
1126
1127 err_ccw_timeout:
1128         qdio_cancel_ccw(irq_ptr, QDIO_FLAG_CLEANUP_USING_CLEAR);
1129 err_ccw_error:
1130 err_ccw_start:
1131         qdio_shutdown_thinint(irq_ptr);
1132 err_thinint:
1133         qdio_shutdown_irq(irq_ptr);
1134         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
1135         mutex_unlock(&irq_ptr->setup_mutex);
1136         return rc;
1137 }
1138 EXPORT_SYMBOL_GPL(qdio_establish);
1139
1140 /**
1141  * qdio_activate - activate queues on a qdio subchannel
1142  * @cdev: associated cdev
1143  */
1144 int qdio_activate(struct ccw_device *cdev)
1145 {
1146         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1147         struct subchannel_id schid;
1148         struct ciw *ciw;
1149         int rc;
1150
1151         ccw_device_get_schid(cdev, &schid);
1152         DBF_EVENT("qactivate:%4x", schid.sch_no);
1153
1154         if (!irq_ptr)
1155                 return -ENODEV;
1156
1157         ciw = ccw_device_get_ciw(cdev, CIW_TYPE_AQUEUE);
1158         if (!ciw) {
1159                 DBF_ERROR("%4x NO AQ", schid.sch_no);
1160                 return -EIO;
1161         }
1162
1163         mutex_lock(&irq_ptr->setup_mutex);
1164         if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
1165                 rc = -EBUSY;
1166                 goto out;
1167         }
1168
1169         irq_ptr->ccw->cmd_code = ciw->cmd;
1170         irq_ptr->ccw->flags = CCW_FLAG_SLI;
1171         irq_ptr->ccw->count = ciw->count;
1172         irq_ptr->ccw->cda = 0;
1173
1174         spin_lock_irq(get_ccwdev_lock(cdev));
1175         ccw_device_set_options(cdev, CCWDEV_REPORT_ALL);
1176
1177         rc = ccw_device_start(cdev, irq_ptr->ccw, QDIO_DOING_ACTIVATE,
1178                               0, DOIO_DENY_PREFETCH);
1179         spin_unlock_irq(get_ccwdev_lock(cdev));
1180         if (rc) {
1181                 DBF_ERROR("%4x act IO ERR", irq_ptr->schid.sch_no);
1182                 DBF_ERROR("rc:%4x", rc);
1183                 goto out;
1184         }
1185
1186         /* wait for subchannel to become active */
1187         msleep(5);
1188
1189         switch (irq_ptr->state) {
1190         case QDIO_IRQ_STATE_STOPPED:
1191         case QDIO_IRQ_STATE_ERR:
1192                 rc = -EIO;
1193                 break;
1194         default:
1195                 qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ACTIVE);
1196                 rc = 0;
1197         }
1198 out:
1199         mutex_unlock(&irq_ptr->setup_mutex);
1200         return rc;
1201 }
1202 EXPORT_SYMBOL_GPL(qdio_activate);
1203
1204 /**
1205  * handle_inbound - reset processed input buffers
1206  * @q: queue containing the buffers
1207  * @bufnr: first buffer to process
1208  * @count: how many buffers are emptied
1209  */
1210 static int handle_inbound(struct qdio_q *q, int bufnr, int count)
1211 {
1212         int overlap;
1213
1214         qperf_inc(q, inbound_call);
1215
1216         /* If any processed SBALs are returned to HW, adjust our tracking: */
1217         overlap = min_t(int, count - sub_buf(q->u.in.batch_start, bufnr),
1218                              q->u.in.batch_count);
1219         if (overlap > 0) {
1220                 q->u.in.batch_start = add_buf(q->u.in.batch_start, overlap);
1221                 q->u.in.batch_count -= overlap;
1222         }
1223
1224         count = set_buf_states(q, bufnr, SLSB_CU_INPUT_EMPTY, count);
1225         atomic_add(count, &q->nr_buf_used);
1226
1227         if (qdio_need_siga_in(q->irq_ptr))
1228                 return qdio_siga_input(q);
1229
1230         return 0;
1231 }
1232
1233 /**
1234  * qdio_add_bufs_to_input_queue - process buffers on an Input Queue
1235  * @cdev: associated ccw_device for the qdio subchannel
1236  * @q_nr: queue number
1237  * @bufnr: buffer number
1238  * @count: how many buffers to process
1239  */
1240 int qdio_add_bufs_to_input_queue(struct ccw_device *cdev, unsigned int q_nr,
1241                                  unsigned int bufnr, unsigned int count)
1242 {
1243         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1244
1245         if (bufnr >= QDIO_MAX_BUFFERS_PER_Q || count > QDIO_MAX_BUFFERS_PER_Q)
1246                 return -EINVAL;
1247
1248         if (!irq_ptr)
1249                 return -ENODEV;
1250
1251         DBF_DEV_EVENT(DBF_INFO, irq_ptr, "addi b:%02x c:%02x", bufnr, count);
1252
1253         if (irq_ptr->state != QDIO_IRQ_STATE_ACTIVE)
1254                 return -EIO;
1255         if (!count)
1256                 return 0;
1257
1258         return handle_inbound(irq_ptr->input_qs[q_nr], bufnr, count);
1259 }
1260 EXPORT_SYMBOL_GPL(qdio_add_bufs_to_input_queue);
1261
1262 /**
1263  * handle_outbound - process filled outbound buffers
1264  * @q: queue containing the buffers
1265  * @bufnr: first buffer to process
1266  * @count: how many buffers are filled
1267  * @aob: asynchronous operation block
1268  */
1269 static int handle_outbound(struct qdio_q *q, unsigned int bufnr, unsigned int count,
1270                            struct qaob *aob)
1271 {
1272         unsigned char state = 0;
1273         int used, rc = 0;
1274
1275         qperf_inc(q, outbound_call);
1276
1277         count = set_buf_states(q, bufnr, SLSB_CU_OUTPUT_PRIMED, count);
1278         used = atomic_add_return(count, &q->nr_buf_used);
1279
1280         if (used == QDIO_MAX_BUFFERS_PER_Q)
1281                 qperf_inc(q, outbound_queue_full);
1282
1283         if (queue_type(q) == QDIO_IQDIO_QFMT) {
1284                 unsigned long phys_aob = aob ? virt_to_phys(aob) : 0;
1285
1286                 WARN_ON_ONCE(!IS_ALIGNED(phys_aob, 256));
1287                 rc = qdio_kick_outbound_q(q, count, phys_aob);
1288         } else if (qdio_need_siga_sync(q->irq_ptr)) {
1289                 rc = qdio_sync_output_queue(q);
1290         } else if (count < QDIO_MAX_BUFFERS_PER_Q &&
1291                    get_buf_state(q, prev_buf(bufnr), &state, 0) > 0 &&
1292                    state == SLSB_CU_OUTPUT_PRIMED) {
1293                 /* The previous buffer is not processed yet, tack on. */
1294                 qperf_inc(q, fast_requeue);
1295         } else {
1296                 rc = qdio_kick_outbound_q(q, count, 0);
1297         }
1298
1299         return rc;
1300 }
1301
1302 /**
1303  * qdio_add_bufs_to_output_queue - process buffers on an Output Queue
1304  * @cdev: associated ccw_device for the qdio subchannel
1305  * @q_nr: queue number
1306  * @bufnr: buffer number
1307  * @count: how many buffers to process
1308  * @aob: asynchronous operation block
1309  */
1310 int qdio_add_bufs_to_output_queue(struct ccw_device *cdev, unsigned int q_nr,
1311                                   unsigned int bufnr, unsigned int count,
1312                                   struct qaob *aob)
1313 {
1314         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1315
1316         if (bufnr >= QDIO_MAX_BUFFERS_PER_Q || count > QDIO_MAX_BUFFERS_PER_Q)
1317                 return -EINVAL;
1318
1319         if (!irq_ptr)
1320                 return -ENODEV;
1321
1322         DBF_DEV_EVENT(DBF_INFO, irq_ptr, "addo b:%02x c:%02x", bufnr, count);
1323
1324         if (irq_ptr->state != QDIO_IRQ_STATE_ACTIVE)
1325                 return -EIO;
1326         if (!count)
1327                 return 0;
1328
1329         return handle_outbound(irq_ptr->output_qs[q_nr], bufnr, count, aob);
1330 }
1331 EXPORT_SYMBOL_GPL(qdio_add_bufs_to_output_queue);
1332
1333 /**
1334  * qdio_start_irq - enable interrupt processing for the device
1335  * @cdev: associated ccw_device for the qdio subchannel
1336  *
1337  * Return codes
1338  *   0 - success
1339  *   1 - irqs not started since new data is available
1340  */
1341 int qdio_start_irq(struct ccw_device *cdev)
1342 {
1343         struct qdio_q *q;
1344         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1345         unsigned int i;
1346
1347         if (!irq_ptr)
1348                 return -ENODEV;
1349
1350         for_each_input_queue(irq_ptr, q, i)
1351                 qdio_stop_polling(q);
1352
1353         clear_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state);
1354
1355         /*
1356          * We need to check again to not lose initiative after
1357          * resetting the ACK state.
1358          */
1359         if (test_nonshared_ind(irq_ptr))
1360                 goto rescan;
1361
1362         for_each_input_queue(irq_ptr, q, i) {
1363                 if (!qdio_inbound_q_done(q, q->first_to_check))
1364                         goto rescan;
1365         }
1366
1367         return 0;
1368
1369 rescan:
1370         if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1371                 return 0;
1372         else
1373                 return 1;
1374
1375 }
1376 EXPORT_SYMBOL(qdio_start_irq);
1377
1378 /**
1379  * qdio_stop_irq - disable interrupt processing for the device
1380  * @cdev: associated ccw_device for the qdio subchannel
1381  *
1382  * Return codes
1383  *   0 - interrupts were already disabled
1384  *   1 - interrupts successfully disabled
1385  */
1386 int qdio_stop_irq(struct ccw_device *cdev)
1387 {
1388         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1389
1390         if (!irq_ptr)
1391                 return -ENODEV;
1392
1393         if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1394                 return 0;
1395         else
1396                 return 1;
1397 }
1398 EXPORT_SYMBOL(qdio_stop_irq);
1399
1400 static int __init init_QDIO(void)
1401 {
1402         int rc;
1403
1404         rc = qdio_debug_init();
1405         if (rc)
1406                 return rc;
1407         rc = qdio_setup_init();
1408         if (rc)
1409                 goto out_debug;
1410         rc = qdio_thinint_init();
1411         if (rc)
1412                 goto out_cache;
1413         return 0;
1414
1415 out_cache:
1416         qdio_setup_exit();
1417 out_debug:
1418         qdio_debug_exit();
1419         return rc;
1420 }
1421
1422 static void __exit exit_QDIO(void)
1423 {
1424         qdio_thinint_exit();
1425         qdio_setup_exit();
1426         qdio_debug_exit();
1427 }
1428
1429 module_init(init_QDIO);
1430 module_exit(exit_QDIO);