1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * zfcp device driver 4 * 5 * Setup and helper functions to access QDIO. 6 * 7 * Copyright IBM Corp. 2002, 2020 8 */ 9 10 #define KMSG_COMPONENT "zfcp" 11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 12 13 #include <linux/slab.h> 14 #include <linux/module.h> 15 #include "zfcp_ext.h" 16 #include "zfcp_qdio.h" 17 18 static bool enable_multibuffer = true; 19 module_param_named(datarouter, enable_multibuffer, bool, 0400); 20 MODULE_PARM_DESC(datarouter, "Enable hardware data router support (default on)"); 21 22 static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *dbftag, 23 unsigned int qdio_err) 24 { 25 struct zfcp_adapter *adapter = qdio->adapter; 26 27 dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n"); 28 29 if (qdio_err & QDIO_ERROR_SLSB_STATE) { 30 zfcp_qdio_siosl(adapter); 31 zfcp_erp_adapter_shutdown(adapter, 0, dbftag); 32 return; 33 } 34 zfcp_erp_adapter_reopen(adapter, 35 ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED | 36 ZFCP_STATUS_COMMON_ERP_FAILED, dbftag); 37 } 38 39 static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt) 40 { 41 int i, sbal_idx; 42 43 for (i = first; i < first + cnt; i++) { 44 sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q; 45 memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer)); 46 } 47 } 48 49 /* this needs to be called prior to updating the queue fill level */ 50 static inline void zfcp_qdio_account(struct zfcp_qdio *qdio) 51 { 52 unsigned long long now, span; 53 int used; 54 55 now = get_tod_clock_monotonic(); 56 span = (now - qdio->req_q_time) >> 12; 57 used = QDIO_MAX_BUFFERS_PER_Q - atomic_read(&qdio->req_q_free); 58 qdio->req_q_util += used * span; 59 qdio->req_q_time = now; 60 } 61 62 static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err, 63 int queue_no, int idx, int count, 64 unsigned long parm) 65 { 66 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm; 67 68 if (unlikely(qdio_err)) { 69 zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err); 70 return; 71 } 72 73 /* cleanup all SBALs being program-owned now */ 74 zfcp_qdio_zero_sbals(qdio->req_q, idx, count); 75 76 spin_lock_irq(&qdio->stat_lock); 77 zfcp_qdio_account(qdio); 78 spin_unlock_irq(&qdio->stat_lock); 79 atomic_add(count, &qdio->req_q_free); 80 wake_up(&qdio->req_q_wq); 81 } 82 83 static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err, 84 int queue_no, int idx, int count, 85 unsigned long parm) 86 { 87 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm; 88 struct zfcp_adapter *adapter = qdio->adapter; 89 int sbal_no, sbal_idx; 90 91 if (unlikely(qdio_err)) { 92 if (zfcp_adapter_multi_buffer_active(adapter)) { 93 void *pl[ZFCP_QDIO_MAX_SBALS_PER_REQ + 1]; 94 struct qdio_buffer_element *sbale; 95 u64 req_id; 96 u8 scount; 97 98 memset(pl, 0, 99 ZFCP_QDIO_MAX_SBALS_PER_REQ * sizeof(void *)); 100 sbale = qdio->res_q[idx]->element; 101 req_id = sbale->addr; 102 scount = min(sbale->scount + 1, 103 ZFCP_QDIO_MAX_SBALS_PER_REQ + 1); 104 /* incl. signaling SBAL */ 105 106 for (sbal_no = 0; sbal_no < scount; sbal_no++) { 107 sbal_idx = (idx + sbal_no) % 108 QDIO_MAX_BUFFERS_PER_Q; 109 pl[sbal_no] = qdio->res_q[sbal_idx]; 110 } 111 zfcp_dbf_hba_def_err(adapter, req_id, scount, pl); 112 } 113 zfcp_qdio_handler_error(qdio, "qdires1", qdio_err); 114 return; 115 } 116 117 /* 118 * go through all SBALs from input queue currently 119 * returned by QDIO layer 120 */ 121 for (sbal_no = 0; sbal_no < count; sbal_no++) { 122 sbal_idx = (idx + sbal_no) % QDIO_MAX_BUFFERS_PER_Q; 123 /* go through all SBALEs of SBAL */ 124 zfcp_fsf_reqid_check(qdio, sbal_idx); 125 } 126 127 /* 128 * put SBALs back to response queue 129 */ 130 if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, idx, count)) 131 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdires2"); 132 } 133 134 static struct qdio_buffer_element * 135 zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 136 { 137 struct qdio_buffer_element *sbale; 138 139 /* set last entry flag in current SBALE of current SBAL */ 140 sbale = zfcp_qdio_sbale_curr(qdio, q_req); 141 sbale->eflags |= SBAL_EFLAGS_LAST_ENTRY; 142 143 /* don't exceed last allowed SBAL */ 144 if (q_req->sbal_last == q_req->sbal_limit) 145 return NULL; 146 147 /* set chaining flag in first SBALE of current SBAL */ 148 sbale = zfcp_qdio_sbale_req(qdio, q_req); 149 sbale->sflags |= SBAL_SFLAGS0_MORE_SBALS; 150 151 /* calculate index of next SBAL */ 152 q_req->sbal_last++; 153 q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q; 154 155 /* keep this requests number of SBALs up-to-date */ 156 q_req->sbal_number++; 157 BUG_ON(q_req->sbal_number > ZFCP_QDIO_MAX_SBALS_PER_REQ); 158 159 /* start at first SBALE of new SBAL */ 160 q_req->sbale_curr = 0; 161 162 /* set storage-block type for new SBAL */ 163 sbale = zfcp_qdio_sbale_curr(qdio, q_req); 164 sbale->sflags |= q_req->sbtype; 165 166 return sbale; 167 } 168 169 static struct qdio_buffer_element * 170 zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 171 { 172 if (q_req->sbale_curr == qdio->max_sbale_per_sbal - 1) 173 return zfcp_qdio_sbal_chain(qdio, q_req); 174 q_req->sbale_curr++; 175 return zfcp_qdio_sbale_curr(qdio, q_req); 176 } 177 178 /** 179 * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list 180 * @qdio: pointer to struct zfcp_qdio 181 * @q_req: pointer to struct zfcp_qdio_req 182 * @sg: scatter-gather list 183 * Returns: zero or -EINVAL on error 184 */ 185 int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req, 186 struct scatterlist *sg) 187 { 188 struct qdio_buffer_element *sbale; 189 190 /* set storage-block type for this request */ 191 sbale = zfcp_qdio_sbale_req(qdio, q_req); 192 sbale->sflags |= q_req->sbtype; 193 194 for (; sg; sg = sg_next(sg)) { 195 sbale = zfcp_qdio_sbale_next(qdio, q_req); 196 if (!sbale) { 197 atomic_inc(&qdio->req_q_full); 198 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first, 199 q_req->sbal_number); 200 return -EINVAL; 201 } 202 sbale->addr = sg_phys(sg); 203 sbale->length = sg->length; 204 } 205 return 0; 206 } 207 208 static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio) 209 { 210 if (atomic_read(&qdio->req_q_free) || 211 !(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 212 return 1; 213 return 0; 214 } 215 216 /** 217 * zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary 218 * @qdio: pointer to struct zfcp_qdio 219 * 220 * The req_q_lock must be held by the caller of this function, and 221 * this function may only be called from process context; it will 222 * sleep when waiting for a free sbal. 223 * 224 * Returns: 0 on success, -EIO if there is no free sbal after waiting. 225 */ 226 int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio) 227 { 228 long ret; 229 230 ret = wait_event_interruptible_lock_irq_timeout(qdio->req_q_wq, 231 zfcp_qdio_sbal_check(qdio), qdio->req_q_lock, 5 * HZ); 232 233 if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 234 return -EIO; 235 236 if (ret > 0) 237 return 0; 238 239 if (!ret) { 240 atomic_inc(&qdio->req_q_full); 241 /* assume hanging outbound queue, try queue recovery */ 242 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1"); 243 } 244 245 return -EIO; 246 } 247 248 /** 249 * zfcp_qdio_send - send req to QDIO 250 * @qdio: pointer to struct zfcp_qdio 251 * @q_req: pointer to struct zfcp_qdio_req 252 * Returns: 0 on success, error otherwise 253 */ 254 int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 255 { 256 int retval; 257 u8 sbal_number = q_req->sbal_number; 258 259 spin_lock(&qdio->stat_lock); 260 zfcp_qdio_account(qdio); 261 spin_unlock(&qdio->stat_lock); 262 263 atomic_sub(sbal_number, &qdio->req_q_free); 264 265 retval = do_QDIO(qdio->adapter->ccw_device, QDIO_FLAG_SYNC_OUTPUT, 0, 266 q_req->sbal_first, sbal_number); 267 268 if (unlikely(retval)) { 269 /* Failed to submit the IO, roll back our modifications. */ 270 atomic_add(sbal_number, &qdio->req_q_free); 271 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first, 272 sbal_number); 273 return retval; 274 } 275 276 /* account for transferred buffers */ 277 qdio->req_q_idx += sbal_number; 278 qdio->req_q_idx %= QDIO_MAX_BUFFERS_PER_Q; 279 280 return 0; 281 } 282 283 /** 284 * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data 285 * @qdio: pointer to struct zfcp_qdio 286 * Returns: -ENOMEM on memory allocation error or return value from 287 * qdio_allocate 288 */ 289 static int zfcp_qdio_allocate(struct zfcp_qdio *qdio) 290 { 291 int ret; 292 293 ret = qdio_alloc_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q); 294 if (ret) 295 return -ENOMEM; 296 297 ret = qdio_alloc_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q); 298 if (ret) 299 goto free_req_q; 300 301 init_waitqueue_head(&qdio->req_q_wq); 302 303 ret = qdio_allocate(qdio->adapter->ccw_device, 1, 1); 304 if (ret) 305 goto free_res_q; 306 307 return 0; 308 309 free_res_q: 310 qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q); 311 free_req_q: 312 qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q); 313 return ret; 314 } 315 316 /** 317 * zfcp_close_qdio - close qdio queues for an adapter 318 * @qdio: pointer to structure zfcp_qdio 319 */ 320 void zfcp_qdio_close(struct zfcp_qdio *qdio) 321 { 322 struct zfcp_adapter *adapter = qdio->adapter; 323 int idx, count; 324 325 if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 326 return; 327 328 /* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */ 329 spin_lock_irq(&qdio->req_q_lock); 330 atomic_andnot(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status); 331 spin_unlock_irq(&qdio->req_q_lock); 332 333 wake_up(&qdio->req_q_wq); 334 335 qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR); 336 337 /* cleanup used outbound sbals */ 338 count = atomic_read(&qdio->req_q_free); 339 if (count < QDIO_MAX_BUFFERS_PER_Q) { 340 idx = (qdio->req_q_idx + count) % QDIO_MAX_BUFFERS_PER_Q; 341 count = QDIO_MAX_BUFFERS_PER_Q - count; 342 zfcp_qdio_zero_sbals(qdio->req_q, idx, count); 343 } 344 qdio->req_q_idx = 0; 345 atomic_set(&qdio->req_q_free, 0); 346 } 347 348 void zfcp_qdio_shost_update(struct zfcp_adapter *const adapter, 349 const struct zfcp_qdio *const qdio) 350 { 351 struct Scsi_Host *const shost = adapter->scsi_host; 352 353 if (shost == NULL) 354 return; 355 356 shost->sg_tablesize = qdio->max_sbale_per_req; 357 shost->max_sectors = qdio->max_sbale_per_req * 8; 358 } 359 360 /** 361 * zfcp_qdio_open - prepare and initialize response queue 362 * @qdio: pointer to struct zfcp_qdio 363 * Returns: 0 on success, otherwise -EIO 364 */ 365 int zfcp_qdio_open(struct zfcp_qdio *qdio) 366 { 367 struct qdio_buffer **input_sbals[1] = {qdio->res_q}; 368 struct qdio_buffer **output_sbals[1] = {qdio->req_q}; 369 struct qdio_buffer_element *sbale; 370 struct qdio_initialize init_data = {0}; 371 struct zfcp_adapter *adapter = qdio->adapter; 372 struct ccw_device *cdev = adapter->ccw_device; 373 struct qdio_ssqd_desc ssqd; 374 int cc; 375 376 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP) 377 return -EIO; 378 379 atomic_andnot(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED, 380 &qdio->adapter->status); 381 382 init_data.q_format = QDIO_ZFCP_QFMT; 383 memcpy(init_data.adapter_name, dev_name(&cdev->dev), 8); 384 ASCEBC(init_data.adapter_name, 8); 385 init_data.qib_rflags = QIB_RFLAGS_ENABLE_DATA_DIV; 386 if (enable_multibuffer) 387 init_data.qdr_ac |= QDR_AC_MULTI_BUFFER_ENABLE; 388 init_data.no_input_qs = 1; 389 init_data.no_output_qs = 1; 390 init_data.input_handler = zfcp_qdio_int_resp; 391 init_data.output_handler = zfcp_qdio_int_req; 392 init_data.int_parm = (unsigned long) qdio; 393 init_data.input_sbal_addr_array = input_sbals; 394 init_data.output_sbal_addr_array = output_sbals; 395 init_data.scan_threshold = 396 QDIO_MAX_BUFFERS_PER_Q - ZFCP_QDIO_MAX_SBALS_PER_REQ * 2; 397 398 if (qdio_establish(cdev, &init_data)) 399 goto failed_establish; 400 401 if (qdio_get_ssqd_desc(cdev, &ssqd)) 402 goto failed_qdio; 403 404 if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED) 405 atomic_or(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED, 406 &qdio->adapter->status); 407 408 if (ssqd.qdioac2 & CHSC_AC2_MULTI_BUFFER_ENABLED) { 409 atomic_or(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status); 410 qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER; 411 } else { 412 atomic_andnot(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 = 0; 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_or(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status); 437 438 zfcp_qdio_shost_update(adapter, qdio); 439 440 return 0; 441 442 failed_qdio: 443 qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR); 444 failed_establish: 445 dev_err(&cdev->dev, 446 "Setting up the QDIO connection to the FCP adapter failed\n"); 447 return -EIO; 448 } 449 450 void zfcp_qdio_destroy(struct zfcp_qdio *qdio) 451 { 452 if (!qdio) 453 return; 454 455 if (qdio->adapter->ccw_device) 456 qdio_free(qdio->adapter->ccw_device); 457 458 qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q); 459 qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q); 460 kfree(qdio); 461 } 462 463 int zfcp_qdio_setup(struct zfcp_adapter *adapter) 464 { 465 struct zfcp_qdio *qdio; 466 467 qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL); 468 if (!qdio) 469 return -ENOMEM; 470 471 qdio->adapter = adapter; 472 473 if (zfcp_qdio_allocate(qdio)) { 474 kfree(qdio); 475 return -ENOMEM; 476 } 477 478 spin_lock_init(&qdio->req_q_lock); 479 spin_lock_init(&qdio->stat_lock); 480 481 adapter->qdio = qdio; 482 return 0; 483 } 484 485 /** 486 * zfcp_qdio_siosl - Trigger logging in FCP channel 487 * @adapter: The zfcp_adapter where to trigger logging 488 * 489 * Call the cio siosl function to trigger hardware logging. This 490 * wrapper function sets a flag to ensure hardware logging is only 491 * triggered once before going through qdio shutdown. 492 * 493 * The triggers are always run from qdio tasklet context, so no 494 * additional synchronization is necessary. 495 */ 496 void zfcp_qdio_siosl(struct zfcp_adapter *adapter) 497 { 498 int rc; 499 500 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED) 501 return; 502 503 rc = ccw_device_siosl(adapter->ccw_device); 504 if (!rc) 505 atomic_or(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED, 506 &adapter->status); 507 } 508