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/timer.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 int out_mask, unsigned int in_mask,
  35                                unsigned int fc)
  36 {
  37         register unsigned long __fc asm ("0") = fc;
  38         register unsigned long __schid asm ("1") = schid;
  39         register unsigned long out asm ("2") = out_mask;
  40         register unsigned long in asm ("3") = in_mask;
  41         int cc;
  42
  43         asm volatile(
  44                 "       siga    0\n"
  45                 "       ipm     %0\n"
  46                 "       srl     %0,28\n"
  47                 : "=d" (cc)
  48                 : "d" (__fc), "d" (__schid), "d" (out), "d" (in) : "cc");
  49         return cc;
  50 }
  51
  52 static inline int do_siga_input(unsigned long schid, unsigned int mask,
  53                                 unsigned int fc)
  54 {
  55         register unsigned long __fc asm ("0") = fc;
  56         register unsigned long __schid asm ("1") = schid;
  57         register unsigned long __mask asm ("2") = mask;
  58         int cc;
  59
  60         asm volatile(
  61                 "       siga    0\n"
  62                 "       ipm     %0\n"
  63                 "       srl     %0,28\n"
  64                 : "=d" (cc)
  65                 : "d" (__fc), "d" (__schid), "d" (__mask) : "cc");
  66         return cc;
  67 }
  68
  69 /**
  70  * do_siga_output - perform SIGA-w/wt function
  71  * @schid: subchannel id or in case of QEBSM the subchannel token
  72  * @mask: which output queues to process
  73  * @bb: busy bit indicator, set only if SIGA-w/wt could not access a buffer
  74  * @fc: function code to perform
  75  * @aob: asynchronous operation block
  76  *
  77  * Returns condition code.
  78  * Note: For IQDC unicast queues only the highest priority queue is processed.
  79  */
  80 static inline int do_siga_output(unsigned long schid, unsigned long mask,
  81                                  unsigned int *bb, unsigned int fc,
  82                                  unsigned long aob)
  83 {
  84         register unsigned long __fc asm("0") = fc;
  85         register unsigned long __schid asm("1") = schid;
  86         register unsigned long __mask asm("2") = mask;
  87         register unsigned long __aob asm("3") = aob;
  88         int cc;
  89
  90         asm volatile(
  91                 "       siga    0\n"
  92                 "       ipm     %0\n"
  93                 "       srl     %0,28\n"
  94                 : "=d" (cc), "+d" (__fc), "+d" (__aob)
  95                 : "d" (__schid), "d" (__mask)
  96                 : "cc");
  97         *bb = __fc >> 31;
  98         return cc;
  99 }
 100
 101 /**
 102  * qdio_do_eqbs - extract buffer states for QEBSM
 103  * @q: queue to manipulate
 104  * @state: state of the extracted buffers
 105  * @start: buffer number to start at
 106  * @count: count of buffers to examine
 107  * @auto_ack: automatically acknowledge buffers
 108  *
 109  * Returns the number of successfully extracted equal buffer states.
 110  * Stops processing if a state is different from the last buffers state.
 111  */
 112 static int qdio_do_eqbs(struct qdio_q *q, unsigned char *state,
 113                         int start, int count, int auto_ack)
 114 {
 115         int tmp_count = count, tmp_start = start, nr = q->nr;
 116         unsigned int ccq = 0;
 117
 118         qperf_inc(q, eqbs);
 119
 120         if (!q->is_input_q)
 121                 nr += q->irq_ptr->nr_input_qs;
 122 again:
 123         ccq = do_eqbs(q->irq_ptr->sch_token, state, nr, &tmp_start, &tmp_count,
 124                       auto_ack);
 125
 126         switch (ccq) {
 127         case 0:
 128         case 32:
 129                 /* all done, or next buffer state different */
 130                 return count - tmp_count;
 131         case 96:
 132                 /* not all buffers processed */
 133                 qperf_inc(q, eqbs_partial);
 134                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "EQBS part:%02x",
 135                         tmp_count);
 136                 return count - tmp_count;
 137         case 97:
 138                 /* no buffer processed */
 139                 DBF_DEV_EVENT(DBF_WARN, q->irq_ptr, "EQBS again:%2d", ccq);
 140                 goto again;
 141         default:
 142                 DBF_ERROR("%4x ccq:%3d", SCH_NO(q), ccq);
 143                 DBF_ERROR("%4x EQBS ERROR", SCH_NO(q));
 144                 DBF_ERROR("%3d%3d%2d", count, tmp_count, nr);
 145                 q->handler(q->irq_ptr->cdev, QDIO_ERROR_GET_BUF_STATE, q->nr,
 146                            q->first_to_check, count, q->irq_ptr->int_parm);
 147                 return 0;
 148         }
 149 }
 150
 151 /**
 152  * qdio_do_sqbs - set buffer states for QEBSM
 153  * @q: queue to manipulate
 154  * @state: new state of the buffers
 155  * @start: first buffer number to change
 156  * @count: how many buffers to change
 157  *
 158  * Returns the number of successfully changed buffers.
 159  * Does retrying until the specified count of buffer states is set or an
 160  * error occurs.
 161  */
 162 static int qdio_do_sqbs(struct qdio_q *q, unsigned char state, int start,
 163                         int count)
 164 {
 165         unsigned int ccq = 0;
 166         int tmp_count = count, tmp_start = start;
 167         int nr = q->nr;
 168
 169         if (!count)
 170                 return 0;
 171         qperf_inc(q, sqbs);
 172
 173         if (!q->is_input_q)
 174                 nr += q->irq_ptr->nr_input_qs;
 175 again:
 176         ccq = do_sqbs(q->irq_ptr->sch_token, state, nr, &tmp_start, &tmp_count);
 177
 178         switch (ccq) {
 179         case 0:
 180         case 32:
 181                 /* all done, or active buffer adapter-owned */
 182                 WARN_ON_ONCE(tmp_count);
 183                 return count - tmp_count;
 184         case 96:
 185                 /* not all buffers processed */
 186                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "SQBS again:%2d", ccq);
 187                 qperf_inc(q, sqbs_partial);
 188                 goto again;
 189         default:
 190                 DBF_ERROR("%4x ccq:%3d", SCH_NO(q), ccq);
 191                 DBF_ERROR("%4x SQBS ERROR", SCH_NO(q));
 192                 DBF_ERROR("%3d%3d%2d", count, tmp_count, nr);
 193                 q->handler(q->irq_ptr->cdev, QDIO_ERROR_SET_BUF_STATE, q->nr,
 194                            q->first_to_check, count, q->irq_ptr->int_parm);
 195                 return 0;
 196         }
 197 }
 198
 199 /*
 200  * Returns number of examined buffers and their common state in *state.
 201  * Requested number of buffers-to-examine must be > 0.
 202  */
 203 static inline int get_buf_states(struct qdio_q *q, unsigned int bufnr,
 204                                  unsigned char *state, unsigned int count,
 205                                  int auto_ack)
 206 {
 207         unsigned char __state = 0;
 208         int i = 1;
 209
 210         if (is_qebsm(q))
 211                 return qdio_do_eqbs(q, state, bufnr, count, auto_ack);
 212
 213         /* get initial state: */
 214         __state = q->slsb.val[bufnr];
 215
 216         /* Bail out early if there is no work on the queue: */
 217         if (__state & SLSB_OWNER_CU)
 218                 goto out;
 219
 220         for (; i < count; i++) {
 221                 bufnr = next_buf(bufnr);
 222
 223                 /* stop if next state differs from initial state: */
 224                 if (q->slsb.val[bufnr] != __state)
 225                         break;
 226         }
 227
 228 out:
 229         *state = __state;
 230         return i;
 231 }
 232
 233 static inline int get_buf_state(struct qdio_q *q, unsigned int bufnr,
 234                                 unsigned char *state, int auto_ack)
 235 {
 236         return get_buf_states(q, bufnr, state, 1, auto_ack);
 237 }
 238
 239 /* wrap-around safe setting of slsb states, returns number of changed buffers */
 240 static inline int set_buf_states(struct qdio_q *q, int bufnr,
 241                                  unsigned char state, int count)
 242 {
 243         int i;
 244
 245         if (is_qebsm(q))
 246                 return qdio_do_sqbs(q, state, bufnr, count);
 247
 248         /* Ensure that all preceding changes to the SBALs are visible: */
 249         mb();
 250
 251         for (i = 0; i < count; i++) {
 252                 WRITE_ONCE(q->slsb.val[bufnr], state);
 253                 bufnr = next_buf(bufnr);
 254         }
 255
 256         /* Make our SLSB changes visible: */
 257         mb();
 258
 259         return count;
 260 }
 261
 262 static inline int set_buf_state(struct qdio_q *q, int bufnr,
 263                                 unsigned char state)
 264 {
 265         return set_buf_states(q, bufnr, state, 1);
 266 }
 267
 268 /* set slsb states to initial state */
 269 static void qdio_init_buf_states(struct qdio_irq *irq_ptr)
 270 {
 271         struct qdio_q *q;
 272         int i;
 273
 274         for_each_input_queue(irq_ptr, q, i)
 275                 set_buf_states(q, 0, SLSB_P_INPUT_NOT_INIT,
 276                                QDIO_MAX_BUFFERS_PER_Q);
 277         for_each_output_queue(irq_ptr, q, i)
 278                 set_buf_states(q, 0, SLSB_P_OUTPUT_NOT_INIT,
 279                                QDIO_MAX_BUFFERS_PER_Q);
 280 }
 281
 282 static inline int qdio_siga_sync(struct qdio_q *q, unsigned int output,
 283                           unsigned int input)
 284 {
 285         unsigned long schid = *((u32 *) &q->irq_ptr->schid);
 286         unsigned int fc = QDIO_SIGA_SYNC;
 287         int cc;
 288
 289         DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-s:%1d", q->nr);
 290         qperf_inc(q, siga_sync);
 291
 292         if (is_qebsm(q)) {
 293                 schid = q->irq_ptr->sch_token;
 294                 fc |= QDIO_SIGA_QEBSM_FLAG;
 295         }
 296
 297         cc = do_siga_sync(schid, output, input, fc);
 298         if (unlikely(cc))
 299                 DBF_ERROR("%4x SIGA-S:%2d", SCH_NO(q), cc);
 300         return (cc) ? -EIO : 0;
 301 }
 302
 303 static inline int qdio_siga_sync_q(struct qdio_q *q)
 304 {
 305         if (q->is_input_q)
 306                 return qdio_siga_sync(q, 0, q->mask);
 307         else
 308                 return qdio_siga_sync(q, q->mask, 0);
 309 }
 310
 311 static int qdio_siga_output(struct qdio_q *q, unsigned int count,
 312                             unsigned int *busy_bit, unsigned long aob)
 313 {
 314         unsigned long schid = *((u32 *) &q->irq_ptr->schid);
 315         unsigned int fc = QDIO_SIGA_WRITE;
 316         u64 start_time = 0;
 317         int retries = 0, cc;
 318
 319         if (queue_type(q) == QDIO_IQDIO_QFMT && !multicast_outbound(q)) {
 320                 if (count > 1)
 321                         fc = QDIO_SIGA_WRITEM;
 322                 else if (aob)
 323                         fc = QDIO_SIGA_WRITEQ;
 324         }
 325
 326         if (is_qebsm(q)) {
 327                 schid = q->irq_ptr->sch_token;
 328                 fc |= QDIO_SIGA_QEBSM_FLAG;
 329         }
 330 again:
 331         cc = do_siga_output(schid, q->mask, busy_bit, fc, aob);
 332
 333         /* hipersocket busy condition */
 334         if (unlikely(*busy_bit)) {
 335                 retries++;
 336
 337                 if (!start_time) {
 338                         start_time = get_tod_clock_fast();
 339                         goto again;
 340                 }
 341                 if (get_tod_clock_fast() - start_time < QDIO_BUSY_BIT_PATIENCE)
 342                         goto again;
 343         }
 344         if (retries) {
 345                 DBF_DEV_EVENT(DBF_WARN, q->irq_ptr,
 346                               "%4x cc2 BB1:%1d", SCH_NO(q), q->nr);
 347                 DBF_DEV_EVENT(DBF_WARN, q->irq_ptr, "count:%u", retries);
 348         }
 349         return cc;
 350 }
 351
 352 static inline int qdio_siga_input(struct qdio_q *q)
 353 {
 354         unsigned long schid = *((u32 *) &q->irq_ptr->schid);
 355         unsigned int fc = QDIO_SIGA_READ;
 356         int cc;
 357
 358         DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-r:%1d", q->nr);
 359         qperf_inc(q, siga_read);
 360
 361         if (is_qebsm(q)) {
 362                 schid = q->irq_ptr->sch_token;
 363                 fc |= QDIO_SIGA_QEBSM_FLAG;
 364         }
 365
 366         cc = do_siga_input(schid, q->mask, fc);
 367         if (unlikely(cc))
 368                 DBF_ERROR("%4x SIGA-R:%2d", SCH_NO(q), cc);
 369         return (cc) ? -EIO : 0;
 370 }
 371
 372 #define qdio_siga_sync_out(q) qdio_siga_sync(q, ~0U, 0)
 373 #define qdio_siga_sync_all(q) qdio_siga_sync(q, ~0U, ~0U)
 374
 375 static inline void qdio_sync_queues(struct qdio_q *q)
 376 {
 377         /* PCI capable outbound queues will also be scanned so sync them too */
 378         if (pci_out_supported(q->irq_ptr))
 379                 qdio_siga_sync_all(q);
 380         else
 381                 qdio_siga_sync_q(q);
 382 }
 383
 384 int debug_get_buf_state(struct qdio_q *q, unsigned int bufnr,
 385                         unsigned char *state)
 386 {
 387         if (need_siga_sync(q))
 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         /*
 455          * No siga sync here, as a PCI or we after a thin interrupt
 456          * already sync'ed the queues.
 457          */
 458         count = get_buf_states(q, start, &state, count, 1);
 459         if (!count)
 460                 return 0;
 461
 462         switch (state) {
 463         case SLSB_P_INPUT_PRIMED:
 464                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in prim:%1d %02x", q->nr,
 465                               count);
 466
 467                 inbound_handle_work(q, start, count, is_qebsm(q));
 468                 if (atomic_sub_return(count, &q->nr_buf_used) == 0)
 469                         qperf_inc(q, inbound_queue_full);
 470                 if (q->irq_ptr->perf_stat_enabled)
 471                         account_sbals(q, count);
 472                 return count;
 473         case SLSB_P_INPUT_ERROR:
 474                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in err:%1d %02x", q->nr,
 475                               count);
 476
 477                 *error = QDIO_ERROR_SLSB_STATE;
 478                 process_buffer_error(q, start, count);
 479                 inbound_handle_work(q, start, count, false);
 480                 if (atomic_sub_return(count, &q->nr_buf_used) == 0)
 481                         qperf_inc(q, inbound_queue_full);
 482                 if (q->irq_ptr->perf_stat_enabled)
 483                         account_sbals_error(q, count);
 484                 return count;
 485         case SLSB_CU_INPUT_EMPTY:
 486                 if (q->irq_ptr->perf_stat_enabled)
 487                         q->q_stats.nr_sbal_nop++;
 488                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "in nop:%1d %#02x",
 489                               q->nr, start);
 490                 return 0;
 491         case SLSB_P_INPUT_NOT_INIT:
 492         case SLSB_P_INPUT_ACK:
 493                 /* We should never see this state, throw a WARN: */
 494         default:
 495                 dev_WARN_ONCE(&q->irq_ptr->cdev->dev, 1,
 496                               "found state %#x at index %u on queue %u\n",
 497                               state, start, q->nr);
 498                 return 0;
 499         }
 500 }
 501
 502 static inline int qdio_inbound_q_done(struct qdio_q *q, unsigned int start)
 503 {
 504         unsigned char state = 0;
 505
 506         if (!atomic_read(&q->nr_buf_used))
 507                 return 1;
 508
 509         if (need_siga_sync(q))
 510                 qdio_siga_sync_q(q);
 511         get_buf_state(q, start, &state, 0);
 512
 513         if (state == SLSB_P_INPUT_PRIMED || state == SLSB_P_INPUT_ERROR)
 514                 /* more work coming */
 515                 return 0;
 516
 517         return 1;
 518 }
 519
 520 static inline unsigned long qdio_aob_for_buffer(struct qdio_output_q *q,
 521                                         int bufnr)
 522 {
 523         unsigned long phys_aob = 0;
 524
 525         if (!q->aobs[bufnr]) {
 526                 struct qaob *aob = qdio_allocate_aob();
 527                 q->aobs[bufnr] = aob;
 528         }
 529         if (q->aobs[bufnr]) {
 530                 q->aobs[bufnr]->user1 = (u64) q->sbal_state[bufnr].user;
 531                 phys_aob = virt_to_phys(q->aobs[bufnr]);
 532                 WARN_ON_ONCE(phys_aob & 0xFF);
 533         }
 534
 535         return phys_aob;
 536 }
 537
 538 static inline int qdio_tasklet_schedule(struct qdio_q *q)
 539 {
 540         if (likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE)) {
 541                 tasklet_schedule(&q->u.out.tasklet);
 542                 return 0;
 543         }
 544         return -EPERM;
 545 }
 546
 547 static int get_outbound_buffer_frontier(struct qdio_q *q, unsigned int start,
 548                                         unsigned int *error)
 549 {
 550         unsigned char state = 0;
 551         unsigned int i;
 552         int count;
 553
 554         q->timestamp = get_tod_clock_fast();
 555
 556         if (need_siga_sync(q))
 557                 if (((queue_type(q) != QDIO_IQDIO_QFMT) &&
 558                     !pci_out_supported(q->irq_ptr)) ||
 559                     (queue_type(q) == QDIO_IQDIO_QFMT &&
 560                     multicast_outbound(q)))
 561                         qdio_siga_sync_q(q);
 562
 563         count = atomic_read(&q->nr_buf_used);
 564         if (!count)
 565                 return 0;
 566
 567         count = get_buf_states(q, start, &state, count, 0);
 568         if (!count)
 569                 return 0;
 570
 571         switch (state) {
 572         case SLSB_P_OUTPUT_PENDING:
 573                 /* detach the utilized QAOBs: */
 574                 for (i = 0; i < count; i++)
 575                         q->u.out.aobs[QDIO_BUFNR(start + i)] = NULL;
 576
 577                 *error = QDIO_ERROR_SLSB_PENDING;
 578                 fallthrough;
 579         case SLSB_P_OUTPUT_EMPTY:
 580                 /* the adapter got it */
 581                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr,
 582                         "out empty:%1d %02x", q->nr, count);
 583
 584                 atomic_sub(count, &q->nr_buf_used);
 585                 if (q->irq_ptr->perf_stat_enabled)
 586                         account_sbals(q, count);
 587                 return count;
 588         case SLSB_P_OUTPUT_ERROR:
 589                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out error:%1d %02x",
 590                               q->nr, count);
 591
 592                 *error = QDIO_ERROR_SLSB_STATE;
 593                 process_buffer_error(q, start, count);
 594                 atomic_sub(count, &q->nr_buf_used);
 595                 if (q->irq_ptr->perf_stat_enabled)
 596                         account_sbals_error(q, count);
 597                 return count;
 598         case SLSB_CU_OUTPUT_PRIMED:
 599                 /* the adapter has not fetched the output yet */
 600                 if (q->irq_ptr->perf_stat_enabled)
 601                         q->q_stats.nr_sbal_nop++;
 602                 DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "out primed:%1d",
 603                               q->nr);
 604                 return 0;
 605         case SLSB_P_OUTPUT_HALTED:
 606                 return 0;
 607         case SLSB_P_OUTPUT_NOT_INIT:
 608                 /* We should never see this state, throw a WARN: */
 609         default:
 610                 dev_WARN_ONCE(&q->irq_ptr->cdev->dev, 1,
 611                               "found state %#x at index %u on queue %u\n",
 612                               state, start, q->nr);
 613                 return 0;
 614         }
 615 }
 616
 617 /* all buffers processed? */
 618 static inline int qdio_outbound_q_done(struct qdio_q *q)
 619 {
 620         return atomic_read(&q->nr_buf_used) == 0;
 621 }
 622
 623 static int qdio_kick_outbound_q(struct qdio_q *q, unsigned int count,
 624                                 unsigned long aob)
 625 {
 626         int retries = 0, cc;
 627         unsigned int busy_bit;
 628
 629         if (!need_siga_out(q))
 630                 return 0;
 631
 632         DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w:%1d", q->nr);
 633 retry:
 634         qperf_inc(q, siga_write);
 635
 636         cc = qdio_siga_output(q, count, &busy_bit, aob);
 637         switch (cc) {
 638         case 0:
 639                 break;
 640         case 2:
 641                 if (busy_bit) {
 642                         while (++retries < QDIO_BUSY_BIT_RETRIES) {
 643                                 mdelay(QDIO_BUSY_BIT_RETRY_DELAY);
 644                                 goto retry;
 645                         }
 646                         DBF_ERROR("%4x cc2 BBC:%1d", SCH_NO(q), q->nr);
 647                         cc = -EBUSY;
 648                 } else {
 649                         DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "siga-w cc2:%1d", q->nr);
 650                         cc = -ENOBUFS;
 651                 }
 652                 break;
 653         case 1:
 654         case 3:
 655                 DBF_ERROR("%4x SIGA-W:%1d", SCH_NO(q), cc);
 656                 cc = -EIO;
 657                 break;
 658         }
 659         if (retries) {
 660                 DBF_ERROR("%4x cc2 BB2:%1d", SCH_NO(q), q->nr);
 661                 DBF_ERROR("count:%u", retries);
 662         }
 663         return cc;
 664 }
 665
 666 void qdio_outbound_tasklet(struct tasklet_struct *t)
 667 {
 668         struct qdio_output_q *out_q = from_tasklet(out_q, t, tasklet);
 669         struct qdio_q *q = container_of(out_q, struct qdio_q, u.out);
 670         unsigned int start = q->first_to_check;
 671         unsigned int error = 0;
 672         int count;
 673
 674         qperf_inc(q, tasklet_outbound);
 675         WARN_ON_ONCE(atomic_read(&q->nr_buf_used) < 0);
 676
 677         count = get_outbound_buffer_frontier(q, start, &error);
 678         if (count) {
 679                 q->first_to_check = add_buf(start, count);
 680
 681                 if (q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE) {
 682                         qperf_inc(q, outbound_handler);
 683                         DBF_DEV_EVENT(DBF_INFO, q->irq_ptr, "koh: s:%02x c:%02x",
 684                                       start, count);
 685
 686                         q->handler(q->irq_ptr->cdev, error, q->nr, start,
 687                                    count, q->irq_ptr->int_parm);
 688                 }
 689         }
 690
 691         if (queue_type(q) == QDIO_ZFCP_QFMT && !pci_out_supported(q->irq_ptr) &&
 692             !qdio_outbound_q_done(q))
 693                 goto sched;
 694
 695         if (q->u.out.pci_out_enabled)
 696                 return;
 697
 698         /*
 699          * Now we know that queue type is either qeth without pci enabled
 700          * or HiperSockets. Make sure buffer switch from PRIMED to EMPTY
 701          * is noticed and outbound_handler is called after some time.
 702          */
 703         if (qdio_outbound_q_done(q))
 704                 del_timer_sync(&q->u.out.timer);
 705         else
 706                 if (!timer_pending(&q->u.out.timer) &&
 707                     likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE))
 708                         mod_timer(&q->u.out.timer, jiffies + 10 * HZ);
 709         return;
 710
 711 sched:
 712         qdio_tasklet_schedule(q);
 713 }
 714
 715 void qdio_outbound_timer(struct timer_list *t)
 716 {
 717         struct qdio_q *q = from_timer(q, t, u.out.timer);
 718
 719         qdio_tasklet_schedule(q);
 720 }
 721
 722 static inline void qdio_check_outbound_pci_queues(struct qdio_irq *irq)
 723 {
 724         struct qdio_q *out;
 725         int i;
 726
 727         if (!pci_out_supported(irq) || !irq->scan_threshold)
 728                 return;
 729
 730         for_each_output_queue(irq, out, i)
 731                 if (!qdio_outbound_q_done(out))
 732                         qdio_tasklet_schedule(out);
 733 }
 734
 735 static inline void qdio_set_state(struct qdio_irq *irq_ptr,
 736                                   enum qdio_irq_states state)
 737 {
 738         DBF_DEV_EVENT(DBF_INFO, irq_ptr, "newstate: %1d", state);
 739
 740         irq_ptr->state = state;
 741         mb();
 742 }
 743
 744 static void qdio_irq_check_sense(struct qdio_irq *irq_ptr, struct irb *irb)
 745 {
 746         if (irb->esw.esw0.erw.cons) {
 747                 DBF_ERROR("%4x sense:", irq_ptr->schid.sch_no);
 748                 DBF_ERROR_HEX(irb, 64);
 749                 DBF_ERROR_HEX(irb->ecw, 64);
 750         }
 751 }
 752
 753 /* PCI interrupt handler */
 754 static void qdio_int_handler_pci(struct qdio_irq *irq_ptr)
 755 {
 756         int i;
 757         struct qdio_q *q;
 758
 759         if (unlikely(irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
 760                 return;
 761
 762         qdio_deliver_irq(irq_ptr);
 763         irq_ptr->last_data_irq_time = S390_lowcore.int_clock;
 764
 765         if (!pci_out_supported(irq_ptr) || !irq_ptr->scan_threshold)
 766                 return;
 767
 768         for_each_output_queue(irq_ptr, q, i) {
 769                 if (qdio_outbound_q_done(q))
 770                         continue;
 771                 if (need_siga_sync(q) && need_siga_sync_out_after_pci(q))
 772                         qdio_siga_sync_q(q);
 773                 qdio_tasklet_schedule(q);
 774         }
 775 }
 776
 777 static void qdio_handle_activate_check(struct qdio_irq *irq_ptr,
 778                                        unsigned long intparm, int cstat,
 779                                        int dstat)
 780 {
 781         struct qdio_q *q;
 782
 783         DBF_ERROR("%4x ACT CHECK", irq_ptr->schid.sch_no);
 784         DBF_ERROR("intp :%lx", intparm);
 785         DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
 786
 787         if (irq_ptr->nr_input_qs) {
 788                 q = irq_ptr->input_qs[0];
 789         } else if (irq_ptr->nr_output_qs) {
 790                 q = irq_ptr->output_qs[0];
 791         } else {
 792                 dump_stack();
 793                 goto no_handler;
 794         }
 795
 796         q->handler(q->irq_ptr->cdev, QDIO_ERROR_ACTIVATE,
 797                    q->nr, q->first_to_check, 0, irq_ptr->int_parm);
 798 no_handler:
 799         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
 800         /*
 801          * In case of z/VM LGR (Live Guest Migration) QDIO recovery will happen.
 802          * Therefore we call the LGR detection function here.
 803          */
 804         lgr_info_log();
 805 }
 806
 807 static void qdio_establish_handle_irq(struct qdio_irq *irq_ptr, int cstat,
 808                                       int dstat)
 809 {
 810         DBF_DEV_EVENT(DBF_INFO, irq_ptr, "qest irq");
 811
 812         if (cstat)
 813                 goto error;
 814         if (dstat & ~(DEV_STAT_DEV_END | DEV_STAT_CHN_END))
 815                 goto error;
 816         if (!(dstat & DEV_STAT_DEV_END))
 817                 goto error;
 818         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ESTABLISHED);
 819         return;
 820
 821 error:
 822         DBF_ERROR("%4x EQ:error", irq_ptr->schid.sch_no);
 823         DBF_ERROR("ds: %2x cs:%2x", dstat, cstat);
 824         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
 825 }
 826
 827 /* qdio interrupt handler */
 828 void qdio_int_handler(struct ccw_device *cdev, unsigned long intparm,
 829                       struct irb *irb)
 830 {
 831         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
 832         struct subchannel_id schid;
 833         int cstat, dstat;
 834
 835         if (!intparm || !irq_ptr) {
 836                 ccw_device_get_schid(cdev, &schid);
 837                 DBF_ERROR("qint:%4x", schid.sch_no);
 838                 return;
 839         }
 840
 841         if (irq_ptr->perf_stat_enabled)
 842                 irq_ptr->perf_stat.qdio_int++;
 843
 844         if (IS_ERR(irb)) {
 845                 DBF_ERROR("%4x IO error", irq_ptr->schid.sch_no);
 846                 qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ERR);
 847                 wake_up(&cdev->private->wait_q);
 848                 return;
 849         }
 850         qdio_irq_check_sense(irq_ptr, irb);
 851         cstat = irb->scsw.cmd.cstat;
 852         dstat = irb->scsw.cmd.dstat;
 853
 854         switch (irq_ptr->state) {
 855         case QDIO_IRQ_STATE_INACTIVE:
 856                 qdio_establish_handle_irq(irq_ptr, cstat, dstat);
 857                 break;
 858         case QDIO_IRQ_STATE_CLEANUP:
 859                 qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
 860                 break;
 861         case QDIO_IRQ_STATE_ESTABLISHED:
 862         case QDIO_IRQ_STATE_ACTIVE:
 863                 if (cstat & SCHN_STAT_PCI) {
 864                         qdio_int_handler_pci(irq_ptr);
 865                         return;
 866                 }
 867                 if (cstat || dstat)
 868                         qdio_handle_activate_check(irq_ptr, intparm, cstat,
 869                                                    dstat);
 870                 break;
 871         case QDIO_IRQ_STATE_STOPPED:
 872                 break;
 873         default:
 874                 WARN_ON_ONCE(1);
 875         }
 876         wake_up(&cdev->private->wait_q);
 877 }
 878
 879 /**
 880  * qdio_get_ssqd_desc - get qdio subchannel description
 881  * @cdev: ccw device to get description for
 882  * @data: where to store the ssqd
 883  *
 884  * Returns 0 or an error code. The results of the chsc are stored in the
 885  * specified structure.
 886  */
 887 int qdio_get_ssqd_desc(struct ccw_device *cdev,
 888                        struct qdio_ssqd_desc *data)
 889 {
 890         struct subchannel_id schid;
 891
 892         if (!cdev || !cdev->private)
 893                 return -EINVAL;
 894
 895         ccw_device_get_schid(cdev, &schid);
 896         DBF_EVENT("get ssqd:%4x", schid.sch_no);
 897         return qdio_setup_get_ssqd(NULL, &schid, data);
 898 }
 899 EXPORT_SYMBOL_GPL(qdio_get_ssqd_desc);
 900
 901 static void qdio_shutdown_queues(struct qdio_irq *irq_ptr)
 902 {
 903         struct qdio_q *q;
 904         int i;
 905
 906         for_each_output_queue(irq_ptr, q, i) {
 907                 del_timer_sync(&q->u.out.timer);
 908                 tasklet_kill(&q->u.out.tasklet);
 909         }
 910 }
 911
 912 /**
 913  * qdio_shutdown - shut down a qdio subchannel
 914  * @cdev: associated ccw device
 915  * @how: use halt or clear to shutdown
 916  */
 917 int qdio_shutdown(struct ccw_device *cdev, int how)
 918 {
 919         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
 920         struct subchannel_id schid;
 921         int rc;
 922
 923         if (!irq_ptr)
 924                 return -ENODEV;
 925
 926         WARN_ON_ONCE(irqs_disabled());
 927         ccw_device_get_schid(cdev, &schid);
 928         DBF_EVENT("qshutdown:%4x", schid.sch_no);
 929
 930         mutex_lock(&irq_ptr->setup_mutex);
 931         /*
 932          * Subchannel was already shot down. We cannot prevent being called
 933          * twice since cio may trigger a shutdown asynchronously.
 934          */
 935         if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
 936                 mutex_unlock(&irq_ptr->setup_mutex);
 937                 return 0;
 938         }
 939
 940         /*
 941          * Indicate that the device is going down. Scheduling the queue
 942          * tasklets is forbidden from here on.
 943          */
 944         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_STOPPED);
 945
 946         qdio_shutdown_queues(irq_ptr);
 947         qdio_shutdown_debug_entries(irq_ptr);
 948
 949         /* cleanup subchannel */
 950         spin_lock_irq(get_ccwdev_lock(cdev));
 951         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_CLEANUP);
 952         if (how & QDIO_FLAG_CLEANUP_USING_CLEAR)
 953                 rc = ccw_device_clear(cdev, QDIO_DOING_CLEANUP);
 954         else
 955                 /* default behaviour is halt */
 956                 rc = ccw_device_halt(cdev, QDIO_DOING_CLEANUP);
 957         spin_unlock_irq(get_ccwdev_lock(cdev));
 958         if (rc) {
 959                 DBF_ERROR("%4x SHUTD ERR", irq_ptr->schid.sch_no);
 960                 DBF_ERROR("rc:%4d", rc);
 961                 goto no_cleanup;
 962         }
 963
 964         wait_event_interruptible_timeout(cdev->private->wait_q,
 965                 irq_ptr->state == QDIO_IRQ_STATE_INACTIVE ||
 966                 irq_ptr->state == QDIO_IRQ_STATE_ERR,
 967                 10 * HZ);
 968
 969 no_cleanup:
 970         qdio_shutdown_thinint(irq_ptr);
 971         qdio_shutdown_irq(irq_ptr);
 972
 973         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
 974         mutex_unlock(&irq_ptr->setup_mutex);
 975         if (rc)
 976                 return rc;
 977         return 0;
 978 }
 979 EXPORT_SYMBOL_GPL(qdio_shutdown);
 980
 981 /**
 982  * qdio_free - free data structures for a qdio subchannel
 983  * @cdev: associated ccw device
 984  */
 985 int qdio_free(struct ccw_device *cdev)
 986 {
 987         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
 988         struct subchannel_id schid;
 989
 990         if (!irq_ptr)
 991                 return -ENODEV;
 992
 993         ccw_device_get_schid(cdev, &schid);
 994         DBF_EVENT("qfree:%4x", schid.sch_no);
 995         DBF_DEV_EVENT(DBF_ERR, irq_ptr, "dbf abandoned");
 996         mutex_lock(&irq_ptr->setup_mutex);
 997
 998         irq_ptr->debug_area = NULL;
 999         cdev->private->qdio_data = NULL;
1000         mutex_unlock(&irq_ptr->setup_mutex);
1001
1002         qdio_free_async_data(irq_ptr);
1003         qdio_free_queues(irq_ptr);
1004         free_page((unsigned long) irq_ptr->qdr);
1005         free_page(irq_ptr->chsc_page);
1006         free_page((unsigned long) irq_ptr);
1007         return 0;
1008 }
1009 EXPORT_SYMBOL_GPL(qdio_free);
1010
1011 /**
1012  * qdio_allocate - allocate qdio queues and associated data
1013  * @cdev: associated ccw device
1014  * @no_input_qs: allocate this number of Input Queues
1015  * @no_output_qs: allocate this number of Output Queues
1016  */
1017 int qdio_allocate(struct ccw_device *cdev, unsigned int no_input_qs,
1018                   unsigned int no_output_qs)
1019 {
1020         struct subchannel_id schid;
1021         struct qdio_irq *irq_ptr;
1022         int rc = -ENOMEM;
1023
1024         ccw_device_get_schid(cdev, &schid);
1025         DBF_EVENT("qallocate:%4x", schid.sch_no);
1026
1027         if (no_input_qs > QDIO_MAX_QUEUES_PER_IRQ ||
1028             no_output_qs > QDIO_MAX_QUEUES_PER_IRQ)
1029                 return -EINVAL;
1030
1031         /* irq_ptr must be in GFP_DMA since it contains ccw1.cda */
1032         irq_ptr = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
1033         if (!irq_ptr)
1034                 return -ENOMEM;
1035
1036         irq_ptr->cdev = cdev;
1037         mutex_init(&irq_ptr->setup_mutex);
1038         if (qdio_allocate_dbf(irq_ptr))
1039                 goto err_dbf;
1040
1041         DBF_DEV_EVENT(DBF_ERR, irq_ptr, "alloc niq:%1u noq:%1u", no_input_qs,
1042                       no_output_qs);
1043
1044         /*
1045          * Allocate a page for the chsc calls in qdio_establish.
1046          * Must be pre-allocated since a zfcp recovery will call
1047          * qdio_establish. In case of low memory and swap on a zfcp disk
1048          * we may not be able to allocate memory otherwise.
1049          */
1050         irq_ptr->chsc_page = get_zeroed_page(GFP_KERNEL);
1051         if (!irq_ptr->chsc_page)
1052                 goto err_chsc;
1053
1054         /* qdr is used in ccw1.cda which is u32 */
1055         irq_ptr->qdr = (struct qdr *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
1056         if (!irq_ptr->qdr)
1057                 goto err_qdr;
1058
1059         rc = qdio_allocate_qs(irq_ptr, no_input_qs, no_output_qs);
1060         if (rc)
1061                 goto err_queues;
1062
1063         cdev->private->qdio_data = irq_ptr;
1064         qdio_set_state(irq_ptr, QDIO_IRQ_STATE_INACTIVE);
1065         return 0;
1066
1067 err_queues:
1068         free_page((unsigned long) irq_ptr->qdr);
1069 err_qdr:
1070         free_page(irq_ptr->chsc_page);
1071 err_chsc:
1072 err_dbf:
1073         free_page((unsigned long) irq_ptr);
1074         return rc;
1075 }
1076 EXPORT_SYMBOL_GPL(qdio_allocate);
1077
1078 static void qdio_detect_hsicq(struct qdio_irq *irq_ptr)
1079 {
1080         struct qdio_q *q = irq_ptr->input_qs[0];
1081         int i, use_cq = 0;
1082
1083         if (irq_ptr->nr_input_qs > 1 && queue_type(q) == QDIO_IQDIO_QFMT)
1084                 use_cq = 1;
1085
1086         for_each_output_queue(irq_ptr, q, i) {
1087                 if (use_cq) {
1088                         if (multicast_outbound(q))
1089                                 continue;
1090                         if (qdio_enable_async_operation(&q->u.out) < 0) {
1091                                 use_cq = 0;
1092                                 continue;
1093                         }
1094                 } else
1095                         qdio_disable_async_operation(&q->u.out);
1096         }
1097         DBF_EVENT("use_cq:%d", use_cq);
1098 }
1099
1100 static void qdio_trace_init_data(struct qdio_irq *irq,
1101                                  struct qdio_initialize *data)
1102 {
1103         DBF_DEV_EVENT(DBF_ERR, irq, "qfmt:%1u", data->q_format);
1104         DBF_DEV_EVENT(DBF_ERR, irq, "qpff%4x", data->qib_param_field_format);
1105         DBF_DEV_HEX(irq, &data->qib_param_field, sizeof(void *), DBF_ERR);
1106         DBF_DEV_HEX(irq, &data->input_slib_elements, sizeof(void *), DBF_ERR);
1107         DBF_DEV_HEX(irq, &data->output_slib_elements, sizeof(void *), DBF_ERR);
1108         DBF_DEV_EVENT(DBF_ERR, irq, "niq:%1u noq:%1u", data->no_input_qs,
1109                       data->no_output_qs);
1110         DBF_DEV_HEX(irq, &data->input_handler, sizeof(void *), DBF_ERR);
1111         DBF_DEV_HEX(irq, &data->output_handler, sizeof(void *), DBF_ERR);
1112         DBF_DEV_HEX(irq, &data->int_parm, sizeof(long), DBF_ERR);
1113         DBF_DEV_HEX(irq, &data->input_sbal_addr_array, sizeof(void *), DBF_ERR);
1114         DBF_DEV_HEX(irq, &data->output_sbal_addr_array, sizeof(void *),
1115                     DBF_ERR);
1116 }
1117
1118 /**
1119  * qdio_establish - establish queues on a qdio subchannel
1120  * @cdev: associated ccw device
1121  * @init_data: initialization data
1122  */
1123 int qdio_establish(struct ccw_device *cdev,
1124                    struct qdio_initialize *init_data)
1125 {
1126         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1127         struct subchannel_id schid;
1128         int rc;
1129
1130         ccw_device_get_schid(cdev, &schid);
1131         DBF_EVENT("qestablish:%4x", schid.sch_no);
1132
1133         if (!irq_ptr)
1134                 return -ENODEV;
1135
1136         if (init_data->no_input_qs > irq_ptr->max_input_qs ||
1137             init_data->no_output_qs > irq_ptr->max_output_qs)
1138                 return -EINVAL;
1139
1140         if ((init_data->no_input_qs && !init_data->input_handler) ||
1141             (init_data->no_output_qs && !init_data->output_handler))
1142                 return -EINVAL;
1143
1144         if (!init_data->input_sbal_addr_array ||
1145             !init_data->output_sbal_addr_array)
1146                 return -EINVAL;
1147
1148         if (!init_data->irq_poll)
1149                 return -EINVAL;
1150
1151         mutex_lock(&irq_ptr->setup_mutex);
1152         qdio_trace_init_data(irq_ptr, init_data);
1153         qdio_setup_irq(irq_ptr, init_data);
1154
1155         rc = qdio_establish_thinint(irq_ptr);
1156         if (rc) {
1157                 qdio_shutdown_irq(irq_ptr);
1158                 mutex_unlock(&irq_ptr->setup_mutex);
1159                 return rc;
1160         }
1161
1162         /* establish q */
1163         irq_ptr->ccw.cmd_code = irq_ptr->equeue.cmd;
1164         irq_ptr->ccw.flags = CCW_FLAG_SLI;
1165         irq_ptr->ccw.count = irq_ptr->equeue.count;
1166         irq_ptr->ccw.cda = (u32)((addr_t)irq_ptr->qdr);
1167
1168         spin_lock_irq(get_ccwdev_lock(cdev));
1169         ccw_device_set_options_mask(cdev, 0);
1170
1171         rc = ccw_device_start(cdev, &irq_ptr->ccw, QDIO_DOING_ESTABLISH, 0, 0);
1172         spin_unlock_irq(get_ccwdev_lock(cdev));
1173         if (rc) {
1174                 DBF_ERROR("%4x est IO ERR", irq_ptr->schid.sch_no);
1175                 DBF_ERROR("rc:%4x", rc);
1176                 qdio_shutdown_thinint(irq_ptr);
1177                 qdio_shutdown_irq(irq_ptr);
1178                 mutex_unlock(&irq_ptr->setup_mutex);
1179                 return rc;
1180         }
1181
1182         wait_event_interruptible_timeout(cdev->private->wait_q,
1183                 irq_ptr->state == QDIO_IRQ_STATE_ESTABLISHED ||
1184                 irq_ptr->state == QDIO_IRQ_STATE_ERR, HZ);
1185
1186         if (irq_ptr->state != QDIO_IRQ_STATE_ESTABLISHED) {
1187                 mutex_unlock(&irq_ptr->setup_mutex);
1188                 qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
1189                 return -EIO;
1190         }
1191
1192         qdio_setup_ssqd_info(irq_ptr);
1193
1194         qdio_detect_hsicq(irq_ptr);
1195
1196         /* qebsm is now setup if available, initialize buffer states */
1197         qdio_init_buf_states(irq_ptr);
1198
1199         mutex_unlock(&irq_ptr->setup_mutex);
1200         qdio_print_subchannel_info(irq_ptr);
1201         qdio_setup_debug_entries(irq_ptr);
1202         return 0;
1203 }
1204 EXPORT_SYMBOL_GPL(qdio_establish);
1205
1206 /**
1207  * qdio_activate - activate queues on a qdio subchannel
1208  * @cdev: associated cdev
1209  */
1210 int qdio_activate(struct ccw_device *cdev)
1211 {
1212         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1213         struct subchannel_id schid;
1214         int rc;
1215
1216         ccw_device_get_schid(cdev, &schid);
1217         DBF_EVENT("qactivate:%4x", schid.sch_no);
1218
1219         if (!irq_ptr)
1220                 return -ENODEV;
1221
1222         mutex_lock(&irq_ptr->setup_mutex);
1223         if (irq_ptr->state == QDIO_IRQ_STATE_INACTIVE) {
1224                 rc = -EBUSY;
1225                 goto out;
1226         }
1227
1228         irq_ptr->ccw.cmd_code = irq_ptr->aqueue.cmd;
1229         irq_ptr->ccw.flags = CCW_FLAG_SLI;
1230         irq_ptr->ccw.count = irq_ptr->aqueue.count;
1231         irq_ptr->ccw.cda = 0;
1232
1233         spin_lock_irq(get_ccwdev_lock(cdev));
1234         ccw_device_set_options(cdev, CCWDEV_REPORT_ALL);
1235
1236         rc = ccw_device_start(cdev, &irq_ptr->ccw, QDIO_DOING_ACTIVATE,
1237                               0, DOIO_DENY_PREFETCH);
1238         spin_unlock_irq(get_ccwdev_lock(cdev));
1239         if (rc) {
1240                 DBF_ERROR("%4x act IO ERR", irq_ptr->schid.sch_no);
1241                 DBF_ERROR("rc:%4x", rc);
1242                 goto out;
1243         }
1244
1245         /* wait for subchannel to become active */
1246         msleep(5);
1247
1248         switch (irq_ptr->state) {
1249         case QDIO_IRQ_STATE_STOPPED:
1250         case QDIO_IRQ_STATE_ERR:
1251                 rc = -EIO;
1252                 break;
1253         default:
1254                 qdio_set_state(irq_ptr, QDIO_IRQ_STATE_ACTIVE);
1255                 rc = 0;
1256         }
1257 out:
1258         mutex_unlock(&irq_ptr->setup_mutex);
1259         return rc;
1260 }
1261 EXPORT_SYMBOL_GPL(qdio_activate);
1262
1263 /**
1264  * handle_inbound - reset processed input buffers
1265  * @q: queue containing the buffers
1266  * @callflags: flags
1267  * @bufnr: first buffer to process
1268  * @count: how many buffers are emptied
1269  */
1270 static int handle_inbound(struct qdio_q *q, unsigned int callflags,
1271                           int bufnr, int count)
1272 {
1273         int overlap;
1274
1275         qperf_inc(q, inbound_call);
1276
1277         /* If any processed SBALs are returned to HW, adjust our tracking: */
1278         overlap = min_t(int, count - sub_buf(q->u.in.batch_start, bufnr),
1279                              q->u.in.batch_count);
1280         if (overlap > 0) {
1281                 q->u.in.batch_start = add_buf(q->u.in.batch_start, overlap);
1282                 q->u.in.batch_count -= overlap;
1283         }
1284
1285         count = set_buf_states(q, bufnr, SLSB_CU_INPUT_EMPTY, count);
1286         atomic_add(count, &q->nr_buf_used);
1287
1288         if (need_siga_in(q))
1289                 return qdio_siga_input(q);
1290
1291         return 0;
1292 }
1293
1294 /**
1295  * handle_outbound - process filled outbound buffers
1296  * @q: queue containing the buffers
1297  * @callflags: flags
1298  * @bufnr: first buffer to process
1299  * @count: how many buffers are filled
1300  */
1301 static int handle_outbound(struct qdio_q *q, unsigned int callflags,
1302                            unsigned int bufnr, unsigned int count)
1303 {
1304         const unsigned int scan_threshold = q->irq_ptr->scan_threshold;
1305         unsigned char state = 0;
1306         int used, rc = 0;
1307
1308         qperf_inc(q, outbound_call);
1309
1310         count = set_buf_states(q, bufnr, SLSB_CU_OUTPUT_PRIMED, count);
1311         used = atomic_add_return(count, &q->nr_buf_used);
1312
1313         if (used == QDIO_MAX_BUFFERS_PER_Q)
1314                 qperf_inc(q, outbound_queue_full);
1315
1316         if (callflags & QDIO_FLAG_PCI_OUT) {
1317                 q->u.out.pci_out_enabled = 1;
1318                 qperf_inc(q, pci_request_int);
1319         } else
1320                 q->u.out.pci_out_enabled = 0;
1321
1322         if (queue_type(q) == QDIO_IQDIO_QFMT) {
1323                 unsigned long phys_aob = 0;
1324
1325                 if (q->u.out.use_cq && count == 1)
1326                         phys_aob = qdio_aob_for_buffer(&q->u.out, bufnr);
1327
1328                 rc = qdio_kick_outbound_q(q, count, phys_aob);
1329         } else if (need_siga_sync(q)) {
1330                 rc = qdio_siga_sync_q(q);
1331         } else if (count < QDIO_MAX_BUFFERS_PER_Q &&
1332                    get_buf_state(q, prev_buf(bufnr), &state, 0) > 0 &&
1333                    state == SLSB_CU_OUTPUT_PRIMED) {
1334                 /* The previous buffer is not processed yet, tack on. */
1335                 qperf_inc(q, fast_requeue);
1336         } else {
1337                 rc = qdio_kick_outbound_q(q, count, 0);
1338         }
1339
1340         /* Let drivers implement their own completion scanning: */
1341         if (!scan_threshold)
1342                 return rc;
1343
1344         /* in case of SIGA errors we must process the error immediately */
1345         if (used >= scan_threshold || rc)
1346                 qdio_tasklet_schedule(q);
1347         else
1348                 /* free the SBALs in case of no further traffic */
1349                 if (!timer_pending(&q->u.out.timer) &&
1350                     likely(q->irq_ptr->state == QDIO_IRQ_STATE_ACTIVE))
1351                         mod_timer(&q->u.out.timer, jiffies + HZ);
1352         return rc;
1353 }
1354
1355 /**
1356  * do_QDIO - process input or output buffers
1357  * @cdev: associated ccw_device for the qdio subchannel
1358  * @callflags: input or output and special flags from the program
1359  * @q_nr: queue number
1360  * @bufnr: buffer number
1361  * @count: how many buffers to process
1362  */
1363 int do_QDIO(struct ccw_device *cdev, unsigned int callflags,
1364             int q_nr, unsigned int bufnr, unsigned int count)
1365 {
1366         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1367
1368         if (bufnr >= QDIO_MAX_BUFFERS_PER_Q || count > QDIO_MAX_BUFFERS_PER_Q)
1369                 return -EINVAL;
1370
1371         if (!irq_ptr)
1372                 return -ENODEV;
1373
1374         DBF_DEV_EVENT(DBF_INFO, irq_ptr,
1375                       "do%02x b:%02x c:%02x", callflags, bufnr, count);
1376
1377         if (irq_ptr->state != QDIO_IRQ_STATE_ACTIVE)
1378                 return -EIO;
1379         if (!count)
1380                 return 0;
1381         if (callflags & QDIO_FLAG_SYNC_INPUT)
1382                 return handle_inbound(irq_ptr->input_qs[q_nr],
1383                                       callflags, bufnr, count);
1384         else if (callflags & QDIO_FLAG_SYNC_OUTPUT)
1385                 return handle_outbound(irq_ptr->output_qs[q_nr],
1386                                        callflags, bufnr, count);
1387         return -EINVAL;
1388 }
1389 EXPORT_SYMBOL_GPL(do_QDIO);
1390
1391 /**
1392  * qdio_start_irq - enable interrupt processing for the device
1393  * @cdev: associated ccw_device for the qdio subchannel
1394  *
1395  * Return codes
1396  *   0 - success
1397  *   1 - irqs not started since new data is available
1398  */
1399 int qdio_start_irq(struct ccw_device *cdev)
1400 {
1401         struct qdio_q *q;
1402         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1403         unsigned int i;
1404
1405         if (!irq_ptr)
1406                 return -ENODEV;
1407
1408         for_each_input_queue(irq_ptr, q, i)
1409                 qdio_stop_polling(q);
1410
1411         clear_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state);
1412
1413         /*
1414          * We need to check again to not lose initiative after
1415          * resetting the ACK state.
1416          */
1417         if (test_nonshared_ind(irq_ptr))
1418                 goto rescan;
1419
1420         for_each_input_queue(irq_ptr, q, i) {
1421                 if (!qdio_inbound_q_done(q, q->first_to_check))
1422                         goto rescan;
1423         }
1424
1425         return 0;
1426
1427 rescan:
1428         if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1429                 return 0;
1430         else
1431                 return 1;
1432
1433 }
1434 EXPORT_SYMBOL(qdio_start_irq);
1435
1436 static int __qdio_inspect_queue(struct qdio_q *q, unsigned int *bufnr,
1437                                 unsigned int *error)
1438 {
1439         unsigned int start = q->first_to_check;
1440         int count;
1441
1442         *error = 0;
1443         count = q->is_input_q ? get_inbound_buffer_frontier(q, start, error) :
1444                                 get_outbound_buffer_frontier(q, start, error);
1445         if (count == 0)
1446                 return 0;
1447
1448         *bufnr = start;
1449
1450         /* for the next time */
1451         q->first_to_check = add_buf(start, count);
1452
1453         return count;
1454 }
1455
1456 int qdio_inspect_queue(struct ccw_device *cdev, unsigned int nr, bool is_input,
1457                        unsigned int *bufnr, unsigned int *error)
1458 {
1459         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1460         struct qdio_q *q;
1461
1462         if (!irq_ptr)
1463                 return -ENODEV;
1464         q = is_input ? irq_ptr->input_qs[nr] : irq_ptr->output_qs[nr];
1465
1466         if (need_siga_sync(q))
1467                 qdio_siga_sync_q(q);
1468
1469         return __qdio_inspect_queue(q, bufnr, error);
1470 }
1471 EXPORT_SYMBOL_GPL(qdio_inspect_queue);
1472
1473 /**
1474  * qdio_get_next_buffers - process input buffers
1475  * @cdev: associated ccw_device for the qdio subchannel
1476  * @nr: input queue number
1477  * @bufnr: first filled buffer number
1478  * @error: buffers are in error state
1479  *
1480  * Return codes
1481  *   < 0 - error
1482  *   = 0 - no new buffers found
1483  *   > 0 - number of processed buffers
1484  */
1485 int qdio_get_next_buffers(struct ccw_device *cdev, int nr, int *bufnr,
1486                           int *error)
1487 {
1488         struct qdio_q *q;
1489         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1490
1491         if (!irq_ptr)
1492                 return -ENODEV;
1493         q = irq_ptr->input_qs[nr];
1494
1495         /*
1496          * Cannot rely on automatic sync after interrupt since queues may
1497          * also be examined without interrupt.
1498          */
1499         if (need_siga_sync(q))
1500                 qdio_sync_queues(q);
1501
1502         qdio_check_outbound_pci_queues(irq_ptr);
1503
1504         /* Note: upper-layer MUST stop processing immediately here ... */
1505         if (unlikely(q->irq_ptr->state != QDIO_IRQ_STATE_ACTIVE))
1506                 return -EIO;
1507
1508         return __qdio_inspect_queue(q, bufnr, error);
1509 }
1510 EXPORT_SYMBOL(qdio_get_next_buffers);
1511
1512 /**
1513  * qdio_stop_irq - disable interrupt processing for the device
1514  * @cdev: associated ccw_device for the qdio subchannel
1515  *
1516  * Return codes
1517  *   0 - interrupts were already disabled
1518  *   1 - interrupts successfully disabled
1519  */
1520 int qdio_stop_irq(struct ccw_device *cdev)
1521 {
1522         struct qdio_irq *irq_ptr = cdev->private->qdio_data;
1523
1524         if (!irq_ptr)
1525                 return -ENODEV;
1526
1527         if (test_and_set_bit(QDIO_IRQ_DISABLED, &irq_ptr->poll_state))
1528                 return 0;
1529         else
1530                 return 1;
1531 }
1532 EXPORT_SYMBOL(qdio_stop_irq);
1533
1534 static int __init init_QDIO(void)
1535 {
1536         int rc;
1537
1538         rc = qdio_debug_init();
1539         if (rc)
1540                 return rc;
1541         rc = qdio_setup_init();
1542         if (rc)
1543                 goto out_debug;
1544         rc = qdio_thinint_init();
1545         if (rc)
1546                 goto out_cache;
1547         return 0;
1548
1549 out_cache:
1550         qdio_setup_exit();
1551 out_debug:
1552         qdio_debug_exit();
1553         return rc;
1554 }
1555
1556 static void __exit exit_QDIO(void)
1557 {
1558         qdio_thinint_exit();
1559         qdio_setup_exit();
1560         qdio_debug_exit();
1561 }
1562
1563 module_init(init_QDIO);
1564 module_exit(exit_QDIO);