1 /* 2 * zfcp device driver 3 * 4 * Setup and helper functions to access QDIO. 5 * 6 * Copyright IBM Corporation 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 "zfcp_ext.h" 14 #include "zfcp_qdio.h" 15 16 #define QBUFF_PER_PAGE (PAGE_SIZE / sizeof(struct qdio_buffer)) 17 18 static int zfcp_qdio_buffers_enqueue(struct qdio_buffer **sbal) 19 { 20 int pos; 21 22 for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos += QBUFF_PER_PAGE) { 23 sbal[pos] = (struct qdio_buffer *) get_zeroed_page(GFP_KERNEL); 24 if (!sbal[pos]) 25 return -ENOMEM; 26 } 27 for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos++) 28 if (pos % QBUFF_PER_PAGE) 29 sbal[pos] = sbal[pos - 1] + 1; 30 return 0; 31 } 32 33 static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *id, 34 unsigned int qdio_err) 35 { 36 struct zfcp_adapter *adapter = qdio->adapter; 37 38 dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n"); 39 40 if (qdio_err & QDIO_ERROR_SLSB_STATE) 41 zfcp_qdio_siosl(adapter); 42 zfcp_erp_adapter_reopen(adapter, 43 ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED | 44 ZFCP_STATUS_COMMON_ERP_FAILED, id); 45 } 46 47 static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt) 48 { 49 int i, sbal_idx; 50 51 for (i = first; i < first + cnt; i++) { 52 sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q; 53 memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer)); 54 } 55 } 56 57 /* this needs to be called prior to updating the queue fill level */ 58 static inline void zfcp_qdio_account(struct zfcp_qdio *qdio) 59 { 60 unsigned long long now, span; 61 int used; 62 63 now = get_clock_monotonic(); 64 span = (now - qdio->req_q_time) >> 12; 65 used = QDIO_MAX_BUFFERS_PER_Q - atomic_read(&qdio->req_q_free); 66 qdio->req_q_util += used * span; 67 qdio->req_q_time = now; 68 } 69 70 static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err, 71 int queue_no, int idx, int count, 72 unsigned long parm) 73 { 74 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm; 75 76 if (unlikely(qdio_err)) { 77 zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err); 78 return; 79 } 80 81 /* cleanup all SBALs being program-owned now */ 82 zfcp_qdio_zero_sbals(qdio->req_q, idx, count); 83 84 spin_lock_irq(&qdio->stat_lock); 85 zfcp_qdio_account(qdio); 86 spin_unlock_irq(&qdio->stat_lock); 87 atomic_add(count, &qdio->req_q_free); 88 wake_up(&qdio->req_q_wq); 89 } 90 91 static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err, 92 int queue_no, int idx, int count, 93 unsigned long parm) 94 { 95 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm; 96 int sbal_idx, sbal_no; 97 98 if (unlikely(qdio_err)) { 99 zfcp_qdio_handler_error(qdio, "qdires1", qdio_err); 100 return; 101 } 102 103 /* 104 * go through all SBALs from input queue currently 105 * returned by QDIO layer 106 */ 107 for (sbal_no = 0; sbal_no < count; sbal_no++) { 108 sbal_idx = (idx + sbal_no) % QDIO_MAX_BUFFERS_PER_Q; 109 /* go through all SBALEs of SBAL */ 110 zfcp_fsf_reqid_check(qdio, sbal_idx); 111 } 112 113 /* 114 * put SBALs back to response queue 115 */ 116 if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, idx, count)) 117 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdires2"); 118 } 119 120 static struct qdio_buffer_element * 121 zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 122 { 123 struct qdio_buffer_element *sbale; 124 125 /* set last entry flag in current SBALE of current SBAL */ 126 sbale = zfcp_qdio_sbale_curr(qdio, q_req); 127 sbale->flags |= SBAL_FLAGS_LAST_ENTRY; 128 129 /* don't exceed last allowed SBAL */ 130 if (q_req->sbal_last == q_req->sbal_limit) 131 return NULL; 132 133 /* set chaining flag in first SBALE of current SBAL */ 134 sbale = zfcp_qdio_sbale_req(qdio, q_req); 135 sbale->flags |= SBAL_FLAGS0_MORE_SBALS; 136 137 /* calculate index of next SBAL */ 138 q_req->sbal_last++; 139 q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q; 140 141 /* keep this requests number of SBALs up-to-date */ 142 q_req->sbal_number++; 143 BUG_ON(q_req->sbal_number > ZFCP_QDIO_MAX_SBALS_PER_REQ); 144 145 /* start at first SBALE of new SBAL */ 146 q_req->sbale_curr = 0; 147 148 /* set storage-block type for new SBAL */ 149 sbale = zfcp_qdio_sbale_curr(qdio, q_req); 150 sbale->flags |= q_req->sbtype; 151 152 return sbale; 153 } 154 155 static struct qdio_buffer_element * 156 zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 157 { 158 if (q_req->sbale_curr == ZFCP_QDIO_LAST_SBALE_PER_SBAL) 159 return zfcp_qdio_sbal_chain(qdio, q_req); 160 q_req->sbale_curr++; 161 return zfcp_qdio_sbale_curr(qdio, q_req); 162 } 163 164 /** 165 * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list 166 * @qdio: pointer to struct zfcp_qdio 167 * @q_req: pointer to struct zfcp_qdio_req 168 * @sg: scatter-gather list 169 * @max_sbals: upper bound for number of SBALs to be used 170 * Returns: number of bytes, or error (negativ) 171 */ 172 int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req, 173 struct scatterlist *sg) 174 { 175 struct qdio_buffer_element *sbale; 176 int bytes = 0; 177 178 /* set storage-block type for this request */ 179 sbale = zfcp_qdio_sbale_req(qdio, q_req); 180 sbale->flags |= q_req->sbtype; 181 182 for (; sg; sg = sg_next(sg)) { 183 sbale = zfcp_qdio_sbale_next(qdio, q_req); 184 if (!sbale) { 185 atomic_inc(&qdio->req_q_full); 186 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first, 187 q_req->sbal_number); 188 return -EINVAL; 189 } 190 191 sbale->addr = sg_virt(sg); 192 sbale->length = sg->length; 193 194 bytes += sg->length; 195 } 196 197 return bytes; 198 } 199 200 static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio) 201 { 202 spin_lock_irq(&qdio->req_q_lock); 203 if (atomic_read(&qdio->req_q_free) || 204 !(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 205 return 1; 206 spin_unlock_irq(&qdio->req_q_lock); 207 return 0; 208 } 209 210 /** 211 * zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary 212 * @qdio: pointer to struct zfcp_qdio 213 * 214 * The req_q_lock must be held by the caller of this function, and 215 * this function may only be called from process context; it will 216 * sleep when waiting for a free sbal. 217 * 218 * Returns: 0 on success, -EIO if there is no free sbal after waiting. 219 */ 220 int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio) 221 { 222 long ret; 223 224 spin_unlock_irq(&qdio->req_q_lock); 225 ret = wait_event_interruptible_timeout(qdio->req_q_wq, 226 zfcp_qdio_sbal_check(qdio), 5 * HZ); 227 228 if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 229 return -EIO; 230 231 if (ret > 0) 232 return 0; 233 234 if (!ret) { 235 atomic_inc(&qdio->req_q_full); 236 /* assume hanging outbound queue, try queue recovery */ 237 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1"); 238 } 239 240 spin_lock_irq(&qdio->req_q_lock); 241 return -EIO; 242 } 243 244 /** 245 * zfcp_qdio_send - set PCI flag in first SBALE and send req to QDIO 246 * @qdio: pointer to struct zfcp_qdio 247 * @q_req: pointer to struct zfcp_qdio_req 248 * Returns: 0 on success, error otherwise 249 */ 250 int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 251 { 252 int retval; 253 u8 sbal_number = q_req->sbal_number; 254 255 spin_lock(&qdio->stat_lock); 256 zfcp_qdio_account(qdio); 257 spin_unlock(&qdio->stat_lock); 258 259 retval = do_QDIO(qdio->adapter->ccw_device, QDIO_FLAG_SYNC_OUTPUT, 0, 260 q_req->sbal_first, sbal_number); 261 262 if (unlikely(retval)) { 263 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first, 264 sbal_number); 265 return retval; 266 } 267 268 /* account for transferred buffers */ 269 atomic_sub(sbal_number, &qdio->req_q_free); 270 qdio->req_q_idx += sbal_number; 271 qdio->req_q_idx %= QDIO_MAX_BUFFERS_PER_Q; 272 273 return 0; 274 } 275 276 277 static void zfcp_qdio_setup_init_data(struct qdio_initialize *id, 278 struct zfcp_qdio *qdio) 279 { 280 memset(id, 0, sizeof(*id)); 281 id->cdev = qdio->adapter->ccw_device; 282 id->q_format = QDIO_ZFCP_QFMT; 283 memcpy(id->adapter_name, dev_name(&id->cdev->dev), 8); 284 ASCEBC(id->adapter_name, 8); 285 id->qib_rflags = QIB_RFLAGS_ENABLE_DATA_DIV; 286 id->no_input_qs = 1; 287 id->no_output_qs = 1; 288 id->input_handler = zfcp_qdio_int_resp; 289 id->output_handler = zfcp_qdio_int_req; 290 id->int_parm = (unsigned long) qdio; 291 id->input_sbal_addr_array = (void **) (qdio->res_q); 292 id->output_sbal_addr_array = (void **) (qdio->req_q); 293 id->scan_threshold = 294 QDIO_MAX_BUFFERS_PER_Q - ZFCP_QDIO_MAX_SBALS_PER_REQ * 2; 295 } 296 297 /** 298 * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data 299 * @adapter: pointer to struct zfcp_adapter 300 * Returns: -ENOMEM on memory allocation error or return value from 301 * qdio_allocate 302 */ 303 static int zfcp_qdio_allocate(struct zfcp_qdio *qdio) 304 { 305 struct qdio_initialize init_data; 306 307 if (zfcp_qdio_buffers_enqueue(qdio->req_q) || 308 zfcp_qdio_buffers_enqueue(qdio->res_q)) 309 return -ENOMEM; 310 311 zfcp_qdio_setup_init_data(&init_data, qdio); 312 init_waitqueue_head(&qdio->req_q_wq); 313 314 return qdio_allocate(&init_data); 315 } 316 317 /** 318 * zfcp_close_qdio - close qdio queues for an adapter 319 * @qdio: pointer to structure zfcp_qdio 320 */ 321 void zfcp_qdio_close(struct zfcp_qdio *qdio) 322 { 323 struct zfcp_adapter *adapter = qdio->adapter; 324 int idx, count; 325 326 if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 327 return; 328 329 /* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */ 330 spin_lock_irq(&qdio->req_q_lock); 331 atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status); 332 spin_unlock_irq(&qdio->req_q_lock); 333 334 wake_up(&qdio->req_q_wq); 335 336 qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR); 337 338 /* cleanup used outbound sbals */ 339 count = atomic_read(&qdio->req_q_free); 340 if (count < QDIO_MAX_BUFFERS_PER_Q) { 341 idx = (qdio->req_q_idx + count) % QDIO_MAX_BUFFERS_PER_Q; 342 count = QDIO_MAX_BUFFERS_PER_Q - count; 343 zfcp_qdio_zero_sbals(qdio->req_q, idx, count); 344 } 345 qdio->req_q_idx = 0; 346 atomic_set(&qdio->req_q_free, 0); 347 } 348 349 /** 350 * zfcp_qdio_open - prepare and initialize response queue 351 * @qdio: pointer to struct zfcp_qdio 352 * Returns: 0 on success, otherwise -EIO 353 */ 354 int zfcp_qdio_open(struct zfcp_qdio *qdio) 355 { 356 struct qdio_buffer_element *sbale; 357 struct qdio_initialize init_data; 358 struct zfcp_adapter *adapter = qdio->adapter; 359 struct ccw_device *cdev = adapter->ccw_device; 360 struct qdio_ssqd_desc ssqd; 361 int cc; 362 363 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP) 364 return -EIO; 365 366 atomic_clear_mask(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED, 367 &qdio->adapter->status); 368 369 zfcp_qdio_setup_init_data(&init_data, qdio); 370 371 if (qdio_establish(&init_data)) 372 goto failed_establish; 373 374 if (qdio_get_ssqd_desc(init_data.cdev, &ssqd)) 375 goto failed_qdio; 376 377 if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED) 378 atomic_set_mask(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED, 379 &qdio->adapter->status); 380 381 if (qdio_activate(cdev)) 382 goto failed_qdio; 383 384 for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) { 385 sbale = &(qdio->res_q[cc]->element[0]); 386 sbale->length = 0; 387 sbale->flags = SBAL_FLAGS_LAST_ENTRY; 388 sbale->addr = NULL; 389 } 390 391 if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0, QDIO_MAX_BUFFERS_PER_Q)) 392 goto failed_qdio; 393 394 /* set index of first available SBALS / number of available SBALS */ 395 qdio->req_q_idx = 0; 396 atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q); 397 atomic_set_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status); 398 399 return 0; 400 401 failed_qdio: 402 qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR); 403 failed_establish: 404 dev_err(&cdev->dev, 405 "Setting up the QDIO connection to the FCP adapter failed\n"); 406 return -EIO; 407 } 408 409 void zfcp_qdio_destroy(struct zfcp_qdio *qdio) 410 { 411 int p; 412 413 if (!qdio) 414 return; 415 416 if (qdio->adapter->ccw_device) 417 qdio_free(qdio->adapter->ccw_device); 418 419 for (p = 0; p < QDIO_MAX_BUFFERS_PER_Q; p += QBUFF_PER_PAGE) { 420 free_page((unsigned long) qdio->req_q[p]); 421 free_page((unsigned long) qdio->res_q[p]); 422 } 423 424 kfree(qdio); 425 } 426 427 int zfcp_qdio_setup(struct zfcp_adapter *adapter) 428 { 429 struct zfcp_qdio *qdio; 430 431 qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL); 432 if (!qdio) 433 return -ENOMEM; 434 435 qdio->adapter = adapter; 436 437 if (zfcp_qdio_allocate(qdio)) { 438 zfcp_qdio_destroy(qdio); 439 return -ENOMEM; 440 } 441 442 spin_lock_init(&qdio->req_q_lock); 443 spin_lock_init(&qdio->stat_lock); 444 445 adapter->qdio = qdio; 446 return 0; 447 } 448 449 /** 450 * zfcp_qdio_siosl - Trigger logging in FCP channel 451 * @adapter: The zfcp_adapter where to trigger logging 452 * 453 * Call the cio siosl function to trigger hardware logging. This 454 * wrapper function sets a flag to ensure hardware logging is only 455 * triggered once before going through qdio shutdown. 456 * 457 * The triggers are always run from qdio tasklet context, so no 458 * additional synchronization is necessary. 459 */ 460 void zfcp_qdio_siosl(struct zfcp_adapter *adapter) 461 { 462 int rc; 463 464 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED) 465 return; 466 467 rc = ccw_device_siosl(adapter->ccw_device); 468 if (!rc) 469 atomic_set_mask(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED, 470 &adapter->status); 471 } 472