1 /* 2 * zfcp device driver 3 * 4 * Setup and helper functions to access QDIO. 5 * 6 * Copyright IBM Corp. 2002, 2010 7 */ 8 9 #define KMSG_COMPONENT "zfcp" 10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 11 12 #include <linux/slab.h> 13 #include <linux/module.h> 14 #include "zfcp_ext.h" 15 #include "zfcp_qdio.h" 16 17 #define QBUFF_PER_PAGE (PAGE_SIZE / sizeof(struct qdio_buffer)) 18 19 static bool enable_multibuffer; 20 module_param_named(datarouter, enable_multibuffer, bool, 0400); 21 MODULE_PARM_DESC(datarouter, "Enable hardware data router support"); 22 23 static int zfcp_qdio_buffers_enqueue(struct qdio_buffer **sbal) 24 { 25 int pos; 26 27 for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos += QBUFF_PER_PAGE) { 28 sbal[pos] = (struct qdio_buffer *) get_zeroed_page(GFP_KERNEL); 29 if (!sbal[pos]) 30 return -ENOMEM; 31 } 32 for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos++) 33 if (pos % QBUFF_PER_PAGE) 34 sbal[pos] = sbal[pos - 1] + 1; 35 return 0; 36 } 37 38 static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *id, 39 unsigned int qdio_err) 40 { 41 struct zfcp_adapter *adapter = qdio->adapter; 42 43 dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n"); 44 45 if (qdio_err & QDIO_ERROR_SLSB_STATE) { 46 zfcp_qdio_siosl(adapter); 47 zfcp_erp_adapter_shutdown(adapter, 0, id); 48 return; 49 } 50 zfcp_erp_adapter_reopen(adapter, 51 ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED | 52 ZFCP_STATUS_COMMON_ERP_FAILED, id); 53 } 54 55 static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt) 56 { 57 int i, sbal_idx; 58 59 for (i = first; i < first + cnt; i++) { 60 sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q; 61 memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer)); 62 } 63 } 64 65 /* this needs to be called prior to updating the queue fill level */ 66 static inline void zfcp_qdio_account(struct zfcp_qdio *qdio) 67 { 68 unsigned long long now, span; 69 int used; 70 71 now = get_clock_monotonic(); 72 span = (now - qdio->req_q_time) >> 12; 73 used = QDIO_MAX_BUFFERS_PER_Q - atomic_read(&qdio->req_q_free); 74 qdio->req_q_util += used * span; 75 qdio->req_q_time = now; 76 } 77 78 static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err, 79 int queue_no, int idx, int count, 80 unsigned long parm) 81 { 82 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm; 83 84 if (unlikely(qdio_err)) { 85 zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err); 86 return; 87 } 88 89 /* cleanup all SBALs being program-owned now */ 90 zfcp_qdio_zero_sbals(qdio->req_q, idx, count); 91 92 spin_lock_irq(&qdio->stat_lock); 93 zfcp_qdio_account(qdio); 94 spin_unlock_irq(&qdio->stat_lock); 95 atomic_add(count, &qdio->req_q_free); 96 wake_up(&qdio->req_q_wq); 97 } 98 99 static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err, 100 int queue_no, int idx, int count, 101 unsigned long parm) 102 { 103 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm; 104 struct zfcp_adapter *adapter = qdio->adapter; 105 int sbal_no, sbal_idx; 106 107 if (unlikely(qdio_err)) { 108 if (zfcp_adapter_multi_buffer_active(adapter)) { 109 void *pl[ZFCP_QDIO_MAX_SBALS_PER_REQ + 1]; 110 struct qdio_buffer_element *sbale; 111 u64 req_id; 112 u8 scount; 113 114 memset(pl, 0, 115 ZFCP_QDIO_MAX_SBALS_PER_REQ * sizeof(void *)); 116 sbale = qdio->res_q[idx]->element; 117 req_id = (u64) sbale->addr; 118 scount = min(sbale->scount + 1, 119 ZFCP_QDIO_MAX_SBALS_PER_REQ + 1); 120 /* incl. signaling SBAL */ 121 122 for (sbal_no = 0; sbal_no < scount; sbal_no++) { 123 sbal_idx = (idx + sbal_no) % 124 QDIO_MAX_BUFFERS_PER_Q; 125 pl[sbal_no] = qdio->res_q[sbal_idx]; 126 } 127 zfcp_dbf_hba_def_err(adapter, req_id, scount, pl); 128 } 129 zfcp_qdio_handler_error(qdio, "qdires1", qdio_err); 130 return; 131 } 132 133 /* 134 * go through all SBALs from input queue currently 135 * returned by QDIO layer 136 */ 137 for (sbal_no = 0; sbal_no < count; sbal_no++) { 138 sbal_idx = (idx + sbal_no) % QDIO_MAX_BUFFERS_PER_Q; 139 /* go through all SBALEs of SBAL */ 140 zfcp_fsf_reqid_check(qdio, sbal_idx); 141 } 142 143 /* 144 * put SBALs back to response queue 145 */ 146 if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, idx, count)) 147 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdires2"); 148 } 149 150 static struct qdio_buffer_element * 151 zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 152 { 153 struct qdio_buffer_element *sbale; 154 155 /* set last entry flag in current SBALE of current SBAL */ 156 sbale = zfcp_qdio_sbale_curr(qdio, q_req); 157 sbale->eflags |= SBAL_EFLAGS_LAST_ENTRY; 158 159 /* don't exceed last allowed SBAL */ 160 if (q_req->sbal_last == q_req->sbal_limit) 161 return NULL; 162 163 /* set chaining flag in first SBALE of current SBAL */ 164 sbale = zfcp_qdio_sbale_req(qdio, q_req); 165 sbale->sflags |= SBAL_SFLAGS0_MORE_SBALS; 166 167 /* calculate index of next SBAL */ 168 q_req->sbal_last++; 169 q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q; 170 171 /* keep this requests number of SBALs up-to-date */ 172 q_req->sbal_number++; 173 BUG_ON(q_req->sbal_number > ZFCP_QDIO_MAX_SBALS_PER_REQ); 174 175 /* start at first SBALE of new SBAL */ 176 q_req->sbale_curr = 0; 177 178 /* set storage-block type for new SBAL */ 179 sbale = zfcp_qdio_sbale_curr(qdio, q_req); 180 sbale->sflags |= q_req->sbtype; 181 182 return sbale; 183 } 184 185 static struct qdio_buffer_element * 186 zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 187 { 188 if (q_req->sbale_curr == qdio->max_sbale_per_sbal - 1) 189 return zfcp_qdio_sbal_chain(qdio, q_req); 190 q_req->sbale_curr++; 191 return zfcp_qdio_sbale_curr(qdio, q_req); 192 } 193 194 /** 195 * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list 196 * @qdio: pointer to struct zfcp_qdio 197 * @q_req: pointer to struct zfcp_qdio_req 198 * @sg: scatter-gather list 199 * @max_sbals: upper bound for number of SBALs to be used 200 * Returns: zero or -EINVAL on error 201 */ 202 int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req, 203 struct scatterlist *sg) 204 { 205 struct qdio_buffer_element *sbale; 206 207 /* set storage-block type for this request */ 208 sbale = zfcp_qdio_sbale_req(qdio, q_req); 209 sbale->sflags |= q_req->sbtype; 210 211 for (; sg; sg = sg_next(sg)) { 212 sbale = zfcp_qdio_sbale_next(qdio, q_req); 213 if (!sbale) { 214 atomic_inc(&qdio->req_q_full); 215 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first, 216 q_req->sbal_number); 217 return -EINVAL; 218 } 219 sbale->addr = sg_virt(sg); 220 sbale->length = sg->length; 221 } 222 return 0; 223 } 224 225 static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio) 226 { 227 spin_lock_irq(&qdio->req_q_lock); 228 if (atomic_read(&qdio->req_q_free) || 229 !(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 230 return 1; 231 spin_unlock_irq(&qdio->req_q_lock); 232 return 0; 233 } 234 235 /** 236 * zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary 237 * @qdio: pointer to struct zfcp_qdio 238 * 239 * The req_q_lock must be held by the caller of this function, and 240 * this function may only be called from process context; it will 241 * sleep when waiting for a free sbal. 242 * 243 * Returns: 0 on success, -EIO if there is no free sbal after waiting. 244 */ 245 int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio) 246 { 247 long ret; 248 249 spin_unlock_irq(&qdio->req_q_lock); 250 ret = wait_event_interruptible_timeout(qdio->req_q_wq, 251 zfcp_qdio_sbal_check(qdio), 5 * HZ); 252 253 if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 254 return -EIO; 255 256 if (ret > 0) 257 return 0; 258 259 if (!ret) { 260 atomic_inc(&qdio->req_q_full); 261 /* assume hanging outbound queue, try queue recovery */ 262 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1"); 263 } 264 265 spin_lock_irq(&qdio->req_q_lock); 266 return -EIO; 267 } 268 269 /** 270 * zfcp_qdio_send - set PCI flag in first SBALE and send req to QDIO 271 * @qdio: pointer to struct zfcp_qdio 272 * @q_req: pointer to struct zfcp_qdio_req 273 * Returns: 0 on success, error otherwise 274 */ 275 int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 276 { 277 int retval; 278 u8 sbal_number = q_req->sbal_number; 279 280 spin_lock(&qdio->stat_lock); 281 zfcp_qdio_account(qdio); 282 spin_unlock(&qdio->stat_lock); 283 284 retval = do_QDIO(qdio->adapter->ccw_device, QDIO_FLAG_SYNC_OUTPUT, 0, 285 q_req->sbal_first, sbal_number); 286 287 if (unlikely(retval)) { 288 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first, 289 sbal_number); 290 return retval; 291 } 292 293 /* account for transferred buffers */ 294 atomic_sub(sbal_number, &qdio->req_q_free); 295 qdio->req_q_idx += sbal_number; 296 qdio->req_q_idx %= QDIO_MAX_BUFFERS_PER_Q; 297 298 return 0; 299 } 300 301 302 static void zfcp_qdio_setup_init_data(struct qdio_initialize *id, 303 struct zfcp_qdio *qdio) 304 { 305 memset(id, 0, sizeof(*id)); 306 id->cdev = qdio->adapter->ccw_device; 307 id->q_format = QDIO_ZFCP_QFMT; 308 memcpy(id->adapter_name, dev_name(&id->cdev->dev), 8); 309 ASCEBC(id->adapter_name, 8); 310 id->qib_rflags = QIB_RFLAGS_ENABLE_DATA_DIV; 311 if (enable_multibuffer) 312 id->qdr_ac |= QDR_AC_MULTI_BUFFER_ENABLE; 313 id->no_input_qs = 1; 314 id->no_output_qs = 1; 315 id->input_handler = zfcp_qdio_int_resp; 316 id->output_handler = zfcp_qdio_int_req; 317 id->int_parm = (unsigned long) qdio; 318 id->input_sbal_addr_array = (void **) (qdio->res_q); 319 id->output_sbal_addr_array = (void **) (qdio->req_q); 320 id->scan_threshold = 321 QDIO_MAX_BUFFERS_PER_Q - ZFCP_QDIO_MAX_SBALS_PER_REQ * 2; 322 } 323 324 /** 325 * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data 326 * @adapter: pointer to struct zfcp_adapter 327 * Returns: -ENOMEM on memory allocation error or return value from 328 * qdio_allocate 329 */ 330 static int zfcp_qdio_allocate(struct zfcp_qdio *qdio) 331 { 332 struct qdio_initialize init_data; 333 334 if (zfcp_qdio_buffers_enqueue(qdio->req_q) || 335 zfcp_qdio_buffers_enqueue(qdio->res_q)) 336 return -ENOMEM; 337 338 zfcp_qdio_setup_init_data(&init_data, qdio); 339 init_waitqueue_head(&qdio->req_q_wq); 340 341 return qdio_allocate(&init_data); 342 } 343 344 /** 345 * zfcp_close_qdio - close qdio queues for an adapter 346 * @qdio: pointer to structure zfcp_qdio 347 */ 348 void zfcp_qdio_close(struct zfcp_qdio *qdio) 349 { 350 struct zfcp_adapter *adapter = qdio->adapter; 351 int idx, count; 352 353 if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 354 return; 355 356 /* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */ 357 spin_lock_irq(&qdio->req_q_lock); 358 atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status); 359 spin_unlock_irq(&qdio->req_q_lock); 360 361 wake_up(&qdio->req_q_wq); 362 363 qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR); 364 365 /* cleanup used outbound sbals */ 366 count = atomic_read(&qdio->req_q_free); 367 if (count < QDIO_MAX_BUFFERS_PER_Q) { 368 idx = (qdio->req_q_idx + count) % QDIO_MAX_BUFFERS_PER_Q; 369 count = QDIO_MAX_BUFFERS_PER_Q - count; 370 zfcp_qdio_zero_sbals(qdio->req_q, idx, count); 371 } 372 qdio->req_q_idx = 0; 373 atomic_set(&qdio->req_q_free, 0); 374 } 375 376 /** 377 * zfcp_qdio_open - prepare and initialize response queue 378 * @qdio: pointer to struct zfcp_qdio 379 * Returns: 0 on success, otherwise -EIO 380 */ 381 int zfcp_qdio_open(struct zfcp_qdio *qdio) 382 { 383 struct qdio_buffer_element *sbale; 384 struct qdio_initialize init_data; 385 struct zfcp_adapter *adapter = qdio->adapter; 386 struct ccw_device *cdev = adapter->ccw_device; 387 struct qdio_ssqd_desc ssqd; 388 int cc; 389 390 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP) 391 return -EIO; 392 393 atomic_clear_mask(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED, 394 &qdio->adapter->status); 395 396 zfcp_qdio_setup_init_data(&init_data, qdio); 397 398 if (qdio_establish(&init_data)) 399 goto failed_establish; 400 401 if (qdio_get_ssqd_desc(init_data.cdev, &ssqd)) 402 goto failed_qdio; 403 404 if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED) 405 atomic_set_mask(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED, 406 &qdio->adapter->status); 407 408 if (ssqd.qdioac2 & CHSC_AC2_MULTI_BUFFER_ENABLED) { 409 atomic_set_mask(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status); 410 qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER; 411 } else { 412 atomic_clear_mask(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status); 413 qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER - 1; 414 } 415 416 qdio->max_sbale_per_req = 417 ZFCP_QDIO_MAX_SBALS_PER_REQ * qdio->max_sbale_per_sbal 418 - 2; 419 if (qdio_activate(cdev)) 420 goto failed_qdio; 421 422 for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) { 423 sbale = &(qdio->res_q[cc]->element[0]); 424 sbale->length = 0; 425 sbale->eflags = SBAL_EFLAGS_LAST_ENTRY; 426 sbale->sflags = 0; 427 sbale->addr = NULL; 428 } 429 430 if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0, QDIO_MAX_BUFFERS_PER_Q)) 431 goto failed_qdio; 432 433 /* set index of first available SBALS / number of available SBALS */ 434 qdio->req_q_idx = 0; 435 atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q); 436 atomic_set_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status); 437 438 if (adapter->scsi_host) { 439 adapter->scsi_host->sg_tablesize = qdio->max_sbale_per_req; 440 adapter->scsi_host->max_sectors = qdio->max_sbale_per_req * 8; 441 } 442 443 return 0; 444 445 failed_qdio: 446 qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR); 447 failed_establish: 448 dev_err(&cdev->dev, 449 "Setting up the QDIO connection to the FCP adapter failed\n"); 450 return -EIO; 451 } 452 453 void zfcp_qdio_destroy(struct zfcp_qdio *qdio) 454 { 455 int p; 456 457 if (!qdio) 458 return; 459 460 if (qdio->adapter->ccw_device) 461 qdio_free(qdio->adapter->ccw_device); 462 463 for (p = 0; p < QDIO_MAX_BUFFERS_PER_Q; p += QBUFF_PER_PAGE) { 464 free_page((unsigned long) qdio->req_q[p]); 465 free_page((unsigned long) qdio->res_q[p]); 466 } 467 468 kfree(qdio); 469 } 470 471 int zfcp_qdio_setup(struct zfcp_adapter *adapter) 472 { 473 struct zfcp_qdio *qdio; 474 475 qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL); 476 if (!qdio) 477 return -ENOMEM; 478 479 qdio->adapter = adapter; 480 481 if (zfcp_qdio_allocate(qdio)) { 482 zfcp_qdio_destroy(qdio); 483 return -ENOMEM; 484 } 485 486 spin_lock_init(&qdio->req_q_lock); 487 spin_lock_init(&qdio->stat_lock); 488 489 adapter->qdio = qdio; 490 return 0; 491 } 492 493 /** 494 * zfcp_qdio_siosl - Trigger logging in FCP channel 495 * @adapter: The zfcp_adapter where to trigger logging 496 * 497 * Call the cio siosl function to trigger hardware logging. This 498 * wrapper function sets a flag to ensure hardware logging is only 499 * triggered once before going through qdio shutdown. 500 * 501 * The triggers are always run from qdio tasklet context, so no 502 * additional synchronization is necessary. 503 */ 504 void zfcp_qdio_siosl(struct zfcp_adapter *adapter) 505 { 506 int rc; 507 508 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED) 509 return; 510 511 rc = ccw_device_siosl(adapter->ccw_device); 512 if (!rc) 513 atomic_set_mask(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED, 514 &adapter->status); 515 } 516