1 /* 2 * zfcp device driver 3 * 4 * Setup and helper functions to access QDIO. 5 * 6 * Copyright IBM Corporation 2002, 2008 7 */ 8 9 #define KMSG_COMPONENT "zfcp" 10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 11 12 #include "zfcp_ext.h" 13 14 #define QBUFF_PER_PAGE (PAGE_SIZE / sizeof(struct qdio_buffer)) 15 16 static int zfcp_qdio_buffers_enqueue(struct qdio_buffer **sbal) 17 { 18 int pos; 19 20 for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos += QBUFF_PER_PAGE) { 21 sbal[pos] = (struct qdio_buffer *) get_zeroed_page(GFP_KERNEL); 22 if (!sbal[pos]) 23 return -ENOMEM; 24 } 25 for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos++) 26 if (pos % QBUFF_PER_PAGE) 27 sbal[pos] = sbal[pos - 1] + 1; 28 return 0; 29 } 30 31 static struct qdio_buffer_element * 32 zfcp_qdio_sbale(struct zfcp_qdio_queue *q, int sbal_idx, int sbale_idx) 33 { 34 return &q->sbal[sbal_idx]->element[sbale_idx]; 35 } 36 37 /** 38 * zfcp_qdio_free - free memory used by request- and resposne queue 39 * @adapter: pointer to the zfcp_adapter structure 40 */ 41 void zfcp_qdio_free(struct zfcp_adapter *adapter) 42 { 43 struct qdio_buffer **sbal_req, **sbal_resp; 44 int p; 45 46 if (adapter->ccw_device) 47 qdio_free(adapter->ccw_device); 48 49 sbal_req = adapter->req_q.sbal; 50 sbal_resp = adapter->resp_q.sbal; 51 52 for (p = 0; p < QDIO_MAX_BUFFERS_PER_Q; p += QBUFF_PER_PAGE) { 53 free_page((unsigned long) sbal_req[p]); 54 free_page((unsigned long) sbal_resp[p]); 55 } 56 } 57 58 static void zfcp_qdio_handler_error(struct zfcp_adapter *adapter, char *id) 59 { 60 dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n"); 61 62 zfcp_erp_adapter_reopen(adapter, 63 ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED | 64 ZFCP_STATUS_COMMON_ERP_FAILED, id, NULL); 65 } 66 67 static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt) 68 { 69 int i, sbal_idx; 70 71 for (i = first; i < first + cnt; i++) { 72 sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q; 73 memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer)); 74 } 75 } 76 77 /* this needs to be called prior to updating the queue fill level */ 78 static void zfcp_qdio_account(struct zfcp_adapter *adapter) 79 { 80 ktime_t now; 81 s64 span; 82 int free, used; 83 84 spin_lock(&adapter->qdio_stat_lock); 85 now = ktime_get(); 86 span = ktime_us_delta(now, adapter->req_q_time); 87 free = max(0, atomic_read(&adapter->req_q.count)); 88 used = QDIO_MAX_BUFFERS_PER_Q - free; 89 adapter->req_q_util += used * span; 90 adapter->req_q_time = now; 91 spin_unlock(&adapter->qdio_stat_lock); 92 } 93 94 static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err, 95 int queue_no, int first, int count, 96 unsigned long parm) 97 { 98 struct zfcp_adapter *adapter = (struct zfcp_adapter *) parm; 99 struct zfcp_qdio_queue *queue = &adapter->req_q; 100 101 if (unlikely(qdio_err)) { 102 zfcp_hba_dbf_event_qdio(adapter, qdio_err, first, count); 103 zfcp_qdio_handler_error(adapter, "qdireq1"); 104 return; 105 } 106 107 /* cleanup all SBALs being program-owned now */ 108 zfcp_qdio_zero_sbals(queue->sbal, first, count); 109 110 zfcp_qdio_account(adapter); 111 atomic_add(count, &queue->count); 112 wake_up(&adapter->request_wq); 113 } 114 115 static void zfcp_qdio_reqid_check(struct zfcp_adapter *adapter, 116 unsigned long req_id, int sbal_idx) 117 { 118 struct zfcp_fsf_req *fsf_req; 119 unsigned long flags; 120 121 spin_lock_irqsave(&adapter->req_list_lock, flags); 122 fsf_req = zfcp_reqlist_find(adapter, req_id); 123 124 if (!fsf_req) 125 /* 126 * Unknown request means that we have potentially memory 127 * corruption and must stop the machine immediatly. 128 */ 129 panic("error: unknown request id (%lx) on adapter %s.\n", 130 req_id, dev_name(&adapter->ccw_device->dev)); 131 132 zfcp_reqlist_remove(adapter, fsf_req); 133 spin_unlock_irqrestore(&adapter->req_list_lock, flags); 134 135 fsf_req->sbal_response = sbal_idx; 136 fsf_req->qdio_inb_usage = atomic_read(&adapter->resp_q.count); 137 zfcp_fsf_req_complete(fsf_req); 138 } 139 140 static void zfcp_qdio_resp_put_back(struct zfcp_adapter *adapter, int processed) 141 { 142 struct zfcp_qdio_queue *queue = &adapter->resp_q; 143 struct ccw_device *cdev = adapter->ccw_device; 144 u8 count, start = queue->first; 145 unsigned int retval; 146 147 count = atomic_read(&queue->count) + processed; 148 149 retval = do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, start, count); 150 151 if (unlikely(retval)) { 152 atomic_set(&queue->count, count); 153 /* FIXME: Recover this with an adapter reopen? */ 154 } else { 155 queue->first += count; 156 queue->first %= QDIO_MAX_BUFFERS_PER_Q; 157 atomic_set(&queue->count, 0); 158 } 159 } 160 161 static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err, 162 int queue_no, int first, int count, 163 unsigned long parm) 164 { 165 struct zfcp_adapter *adapter = (struct zfcp_adapter *) parm; 166 struct zfcp_qdio_queue *queue = &adapter->resp_q; 167 struct qdio_buffer_element *sbale; 168 int sbal_idx, sbale_idx, sbal_no; 169 170 if (unlikely(qdio_err)) { 171 zfcp_hba_dbf_event_qdio(adapter, qdio_err, first, count); 172 zfcp_qdio_handler_error(adapter, "qdires1"); 173 return; 174 } 175 176 /* 177 * go through all SBALs from input queue currently 178 * returned by QDIO layer 179 */ 180 for (sbal_no = 0; sbal_no < count; sbal_no++) { 181 sbal_idx = (first + sbal_no) % QDIO_MAX_BUFFERS_PER_Q; 182 183 /* go through all SBALEs of SBAL */ 184 for (sbale_idx = 0; sbale_idx < QDIO_MAX_ELEMENTS_PER_BUFFER; 185 sbale_idx++) { 186 sbale = zfcp_qdio_sbale(queue, sbal_idx, sbale_idx); 187 zfcp_qdio_reqid_check(adapter, 188 (unsigned long) sbale->addr, 189 sbal_idx); 190 if (likely(sbale->flags & SBAL_FLAGS_LAST_ENTRY)) 191 break; 192 }; 193 194 if (unlikely(!(sbale->flags & SBAL_FLAGS_LAST_ENTRY))) 195 dev_warn(&adapter->ccw_device->dev, 196 "A QDIO protocol error occurred, " 197 "operations continue\n"); 198 } 199 200 /* 201 * put range of SBALs back to response queue 202 * (including SBALs which have already been free before) 203 */ 204 zfcp_qdio_resp_put_back(adapter, count); 205 } 206 207 /** 208 * zfcp_qdio_sbale_req - return ptr to SBALE of req_q for a struct zfcp_fsf_req 209 * @fsf_req: pointer to struct fsf_req 210 * Returns: pointer to qdio_buffer_element (SBALE) structure 211 */ 212 struct qdio_buffer_element *zfcp_qdio_sbale_req(struct zfcp_fsf_req *req) 213 { 214 return zfcp_qdio_sbale(&req->adapter->req_q, req->sbal_last, 0); 215 } 216 217 /** 218 * zfcp_qdio_sbale_curr - return curr SBALE on req_q for a struct zfcp_fsf_req 219 * @fsf_req: pointer to struct fsf_req 220 * Returns: pointer to qdio_buffer_element (SBALE) structure 221 */ 222 struct qdio_buffer_element *zfcp_qdio_sbale_curr(struct zfcp_fsf_req *req) 223 { 224 return zfcp_qdio_sbale(&req->adapter->req_q, req->sbal_last, 225 req->sbale_curr); 226 } 227 228 static void zfcp_qdio_sbal_limit(struct zfcp_fsf_req *fsf_req, int max_sbals) 229 { 230 int count = atomic_read(&fsf_req->adapter->req_q.count); 231 count = min(count, max_sbals); 232 fsf_req->sbal_limit = (fsf_req->sbal_first + count - 1) 233 % QDIO_MAX_BUFFERS_PER_Q; 234 } 235 236 static struct qdio_buffer_element * 237 zfcp_qdio_sbal_chain(struct zfcp_fsf_req *fsf_req, unsigned long sbtype) 238 { 239 struct qdio_buffer_element *sbale; 240 241 /* set last entry flag in current SBALE of current SBAL */ 242 sbale = zfcp_qdio_sbale_curr(fsf_req); 243 sbale->flags |= SBAL_FLAGS_LAST_ENTRY; 244 245 /* don't exceed last allowed SBAL */ 246 if (fsf_req->sbal_last == fsf_req->sbal_limit) 247 return NULL; 248 249 /* set chaining flag in first SBALE of current SBAL */ 250 sbale = zfcp_qdio_sbale_req(fsf_req); 251 sbale->flags |= SBAL_FLAGS0_MORE_SBALS; 252 253 /* calculate index of next SBAL */ 254 fsf_req->sbal_last++; 255 fsf_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q; 256 257 /* keep this requests number of SBALs up-to-date */ 258 fsf_req->sbal_number++; 259 260 /* start at first SBALE of new SBAL */ 261 fsf_req->sbale_curr = 0; 262 263 /* set storage-block type for new SBAL */ 264 sbale = zfcp_qdio_sbale_curr(fsf_req); 265 sbale->flags |= sbtype; 266 267 return sbale; 268 } 269 270 static struct qdio_buffer_element * 271 zfcp_qdio_sbale_next(struct zfcp_fsf_req *fsf_req, unsigned long sbtype) 272 { 273 if (fsf_req->sbale_curr == ZFCP_LAST_SBALE_PER_SBAL) 274 return zfcp_qdio_sbal_chain(fsf_req, sbtype); 275 fsf_req->sbale_curr++; 276 return zfcp_qdio_sbale_curr(fsf_req); 277 } 278 279 static void zfcp_qdio_undo_sbals(struct zfcp_fsf_req *fsf_req) 280 { 281 struct qdio_buffer **sbal = fsf_req->adapter->req_q.sbal; 282 int first = fsf_req->sbal_first; 283 int last = fsf_req->sbal_last; 284 int count = (last - first + QDIO_MAX_BUFFERS_PER_Q) % 285 QDIO_MAX_BUFFERS_PER_Q + 1; 286 zfcp_qdio_zero_sbals(sbal, first, count); 287 } 288 289 static int zfcp_qdio_fill_sbals(struct zfcp_fsf_req *fsf_req, 290 unsigned int sbtype, void *start_addr, 291 unsigned int total_length) 292 { 293 struct qdio_buffer_element *sbale; 294 unsigned long remaining, length; 295 void *addr; 296 297 /* split segment up */ 298 for (addr = start_addr, remaining = total_length; remaining > 0; 299 addr += length, remaining -= length) { 300 sbale = zfcp_qdio_sbale_next(fsf_req, sbtype); 301 if (!sbale) { 302 atomic_inc(&fsf_req->adapter->qdio_outb_full); 303 zfcp_qdio_undo_sbals(fsf_req); 304 return -EINVAL; 305 } 306 307 /* new piece must not exceed next page boundary */ 308 length = min(remaining, 309 (PAGE_SIZE - ((unsigned long)addr & 310 (PAGE_SIZE - 1)))); 311 sbale->addr = addr; 312 sbale->length = length; 313 } 314 return 0; 315 } 316 317 /** 318 * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list 319 * @fsf_req: request to be processed 320 * @sbtype: SBALE flags 321 * @sg: scatter-gather list 322 * @max_sbals: upper bound for number of SBALs to be used 323 * Returns: number of bytes, or error (negativ) 324 */ 325 int zfcp_qdio_sbals_from_sg(struct zfcp_fsf_req *fsf_req, unsigned long sbtype, 326 struct scatterlist *sg, int max_sbals) 327 { 328 struct qdio_buffer_element *sbale; 329 int retval, bytes = 0; 330 331 /* figure out last allowed SBAL */ 332 zfcp_qdio_sbal_limit(fsf_req, max_sbals); 333 334 /* set storage-block type for this request */ 335 sbale = zfcp_qdio_sbale_req(fsf_req); 336 sbale->flags |= sbtype; 337 338 for (; sg; sg = sg_next(sg)) { 339 retval = zfcp_qdio_fill_sbals(fsf_req, sbtype, sg_virt(sg), 340 sg->length); 341 if (retval < 0) 342 return retval; 343 bytes += sg->length; 344 } 345 346 /* assume that no other SBALEs are to follow in the same SBAL */ 347 sbale = zfcp_qdio_sbale_curr(fsf_req); 348 sbale->flags |= SBAL_FLAGS_LAST_ENTRY; 349 350 return bytes; 351 } 352 353 /** 354 * zfcp_qdio_send - set PCI flag in first SBALE and send req to QDIO 355 * @fsf_req: pointer to struct zfcp_fsf_req 356 * Returns: 0 on success, error otherwise 357 */ 358 int zfcp_qdio_send(struct zfcp_fsf_req *fsf_req) 359 { 360 struct zfcp_adapter *adapter = fsf_req->adapter; 361 struct zfcp_qdio_queue *req_q = &adapter->req_q; 362 int first = fsf_req->sbal_first; 363 int count = fsf_req->sbal_number; 364 int retval; 365 unsigned int qdio_flags = QDIO_FLAG_SYNC_OUTPUT; 366 367 zfcp_qdio_account(adapter); 368 369 retval = do_QDIO(adapter->ccw_device, qdio_flags, 0, first, count); 370 if (unlikely(retval)) { 371 zfcp_qdio_zero_sbals(req_q->sbal, first, count); 372 return retval; 373 } 374 375 /* account for transferred buffers */ 376 atomic_sub(count, &req_q->count); 377 req_q->first += count; 378 req_q->first %= QDIO_MAX_BUFFERS_PER_Q; 379 return 0; 380 } 381 382 /** 383 * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data 384 * @adapter: pointer to struct zfcp_adapter 385 * Returns: -ENOMEM on memory allocation error or return value from 386 * qdio_allocate 387 */ 388 int zfcp_qdio_allocate(struct zfcp_adapter *adapter) 389 { 390 struct qdio_initialize *init_data; 391 392 if (zfcp_qdio_buffers_enqueue(adapter->req_q.sbal) || 393 zfcp_qdio_buffers_enqueue(adapter->resp_q.sbal)) 394 return -ENOMEM; 395 396 init_data = &adapter->qdio_init_data; 397 398 init_data->cdev = adapter->ccw_device; 399 init_data->q_format = QDIO_ZFCP_QFMT; 400 memcpy(init_data->adapter_name, dev_name(&adapter->ccw_device->dev), 8); 401 ASCEBC(init_data->adapter_name, 8); 402 init_data->qib_param_field_format = 0; 403 init_data->qib_param_field = NULL; 404 init_data->input_slib_elements = NULL; 405 init_data->output_slib_elements = NULL; 406 init_data->no_input_qs = 1; 407 init_data->no_output_qs = 1; 408 init_data->input_handler = zfcp_qdio_int_resp; 409 init_data->output_handler = zfcp_qdio_int_req; 410 init_data->int_parm = (unsigned long) adapter; 411 init_data->flags = QDIO_INBOUND_0COPY_SBALS | 412 QDIO_OUTBOUND_0COPY_SBALS | QDIO_USE_OUTBOUND_PCIS; 413 init_data->input_sbal_addr_array = 414 (void **) (adapter->resp_q.sbal); 415 init_data->output_sbal_addr_array = 416 (void **) (adapter->req_q.sbal); 417 418 return qdio_allocate(init_data); 419 } 420 421 /** 422 * zfcp_close_qdio - close qdio queues for an adapter 423 */ 424 void zfcp_qdio_close(struct zfcp_adapter *adapter) 425 { 426 struct zfcp_qdio_queue *req_q; 427 int first, count; 428 429 if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 430 return; 431 432 /* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */ 433 req_q = &adapter->req_q; 434 spin_lock_bh(&adapter->req_q_lock); 435 atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status); 436 spin_unlock_bh(&adapter->req_q_lock); 437 438 qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR); 439 440 /* cleanup used outbound sbals */ 441 count = atomic_read(&req_q->count); 442 if (count < QDIO_MAX_BUFFERS_PER_Q) { 443 first = (req_q->first + count) % QDIO_MAX_BUFFERS_PER_Q; 444 count = QDIO_MAX_BUFFERS_PER_Q - count; 445 zfcp_qdio_zero_sbals(req_q->sbal, first, count); 446 } 447 req_q->first = 0; 448 atomic_set(&req_q->count, 0); 449 adapter->resp_q.first = 0; 450 atomic_set(&adapter->resp_q.count, 0); 451 } 452 453 /** 454 * zfcp_qdio_open - prepare and initialize response queue 455 * @adapter: pointer to struct zfcp_adapter 456 * Returns: 0 on success, otherwise -EIO 457 */ 458 int zfcp_qdio_open(struct zfcp_adapter *adapter) 459 { 460 struct qdio_buffer_element *sbale; 461 int cc; 462 463 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP) 464 return -EIO; 465 466 if (qdio_establish(&adapter->qdio_init_data)) 467 goto failed_establish; 468 469 if (qdio_activate(adapter->ccw_device)) 470 goto failed_qdio; 471 472 for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) { 473 sbale = &(adapter->resp_q.sbal[cc]->element[0]); 474 sbale->length = 0; 475 sbale->flags = SBAL_FLAGS_LAST_ENTRY; 476 sbale->addr = NULL; 477 } 478 479 if (do_QDIO(adapter->ccw_device, QDIO_FLAG_SYNC_INPUT, 0, 0, 480 QDIO_MAX_BUFFERS_PER_Q)) 481 goto failed_qdio; 482 483 /* set index of first avalable SBALS / number of available SBALS */ 484 adapter->req_q.first = 0; 485 atomic_set(&adapter->req_q.count, QDIO_MAX_BUFFERS_PER_Q); 486 487 return 0; 488 489 failed_qdio: 490 qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR); 491 failed_establish: 492 dev_err(&adapter->ccw_device->dev, 493 "Setting up the QDIO connection to the FCP adapter failed\n"); 494 return -EIO; 495 } 496