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, NULL); 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_dbf_hba_qdio(qdio->adapter->dbf, qdio_err, idx, count); 78 zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err); 79 return; 80 } 81 82 /* cleanup all SBALs being program-owned now */ 83 zfcp_qdio_zero_sbals(qdio->req_q, idx, count); 84 85 spin_lock_irq(&qdio->stat_lock); 86 zfcp_qdio_account(qdio); 87 spin_unlock_irq(&qdio->stat_lock); 88 atomic_add(count, &qdio->req_q_free); 89 wake_up(&qdio->req_q_wq); 90 } 91 92 static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err, 93 int queue_no, int idx, int count, 94 unsigned long parm) 95 { 96 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm; 97 int sbal_idx, sbal_no; 98 99 if (unlikely(qdio_err)) { 100 zfcp_dbf_hba_qdio(qdio->adapter->dbf, qdio_err, idx, count); 101 zfcp_qdio_handler_error(qdio, "qdires1", qdio_err); 102 return; 103 } 104 105 /* 106 * go through all SBALs from input queue currently 107 * returned by QDIO layer 108 */ 109 for (sbal_no = 0; sbal_no < count; sbal_no++) { 110 sbal_idx = (idx + sbal_no) % QDIO_MAX_BUFFERS_PER_Q; 111 /* go through all SBALEs of SBAL */ 112 zfcp_fsf_reqid_check(qdio, sbal_idx); 113 } 114 115 /* 116 * put SBALs back to response queue 117 */ 118 if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, idx, count)) 119 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdires2", NULL); 120 } 121 122 static struct qdio_buffer_element * 123 zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 124 { 125 struct qdio_buffer_element *sbale; 126 127 /* set last entry flag in current SBALE of current SBAL */ 128 sbale = zfcp_qdio_sbale_curr(qdio, q_req); 129 sbale->flags |= SBAL_FLAGS_LAST_ENTRY; 130 131 /* don't exceed last allowed SBAL */ 132 if (q_req->sbal_last == q_req->sbal_limit) 133 return NULL; 134 135 /* set chaining flag in first SBALE of current SBAL */ 136 sbale = zfcp_qdio_sbale_req(qdio, q_req); 137 sbale->flags |= SBAL_FLAGS0_MORE_SBALS; 138 139 /* calculate index of next SBAL */ 140 q_req->sbal_last++; 141 q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q; 142 143 /* keep this requests number of SBALs up-to-date */ 144 q_req->sbal_number++; 145 BUG_ON(q_req->sbal_number > ZFCP_QDIO_MAX_SBALS_PER_REQ); 146 147 /* start at first SBALE of new SBAL */ 148 q_req->sbale_curr = 0; 149 150 /* set storage-block type for new SBAL */ 151 sbale = zfcp_qdio_sbale_curr(qdio, q_req); 152 sbale->flags |= q_req->sbtype; 153 154 return sbale; 155 } 156 157 static struct qdio_buffer_element * 158 zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 159 { 160 if (q_req->sbale_curr == ZFCP_QDIO_LAST_SBALE_PER_SBAL) 161 return zfcp_qdio_sbal_chain(qdio, q_req); 162 q_req->sbale_curr++; 163 return zfcp_qdio_sbale_curr(qdio, q_req); 164 } 165 166 /** 167 * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list 168 * @qdio: pointer to struct zfcp_qdio 169 * @q_req: pointer to struct zfcp_qdio_req 170 * @sg: scatter-gather list 171 * @max_sbals: upper bound for number of SBALs to be used 172 * Returns: number of bytes, or error (negativ) 173 */ 174 int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req, 175 struct scatterlist *sg) 176 { 177 struct qdio_buffer_element *sbale; 178 int bytes = 0; 179 180 /* set storage-block type for this request */ 181 sbale = zfcp_qdio_sbale_req(qdio, q_req); 182 sbale->flags |= q_req->sbtype; 183 184 for (; sg; sg = sg_next(sg)) { 185 sbale = zfcp_qdio_sbale_next(qdio, q_req); 186 if (!sbale) { 187 atomic_inc(&qdio->req_q_full); 188 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first, 189 q_req->sbal_number); 190 return -EINVAL; 191 } 192 193 sbale->addr = sg_virt(sg); 194 sbale->length = sg->length; 195 196 bytes += sg->length; 197 } 198 199 return bytes; 200 } 201 202 static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio) 203 { 204 spin_lock_irq(&qdio->req_q_lock); 205 if (atomic_read(&qdio->req_q_free) || 206 !(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 207 return 1; 208 spin_unlock_irq(&qdio->req_q_lock); 209 return 0; 210 } 211 212 /** 213 * zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary 214 * @qdio: pointer to struct zfcp_qdio 215 * 216 * The req_q_lock must be held by the caller of this function, and 217 * this function may only be called from process context; it will 218 * sleep when waiting for a free sbal. 219 * 220 * Returns: 0 on success, -EIO if there is no free sbal after waiting. 221 */ 222 int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio) 223 { 224 long ret; 225 226 spin_unlock_irq(&qdio->req_q_lock); 227 ret = wait_event_interruptible_timeout(qdio->req_q_wq, 228 zfcp_qdio_sbal_check(qdio), 5 * HZ); 229 230 if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 231 return -EIO; 232 233 if (ret > 0) 234 return 0; 235 236 if (!ret) { 237 atomic_inc(&qdio->req_q_full); 238 /* assume hanging outbound queue, try queue recovery */ 239 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1", NULL); 240 } 241 242 spin_lock_irq(&qdio->req_q_lock); 243 return -EIO; 244 } 245 246 /** 247 * zfcp_qdio_send - set PCI flag in first SBALE and send req to QDIO 248 * @qdio: pointer to struct zfcp_qdio 249 * @q_req: pointer to struct zfcp_qdio_req 250 * Returns: 0 on success, error otherwise 251 */ 252 int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req) 253 { 254 int retval; 255 u8 sbal_number = q_req->sbal_number; 256 257 spin_lock(&qdio->stat_lock); 258 zfcp_qdio_account(qdio); 259 spin_unlock(&qdio->stat_lock); 260 261 retval = do_QDIO(qdio->adapter->ccw_device, QDIO_FLAG_SYNC_OUTPUT, 0, 262 q_req->sbal_first, sbal_number); 263 264 if (unlikely(retval)) { 265 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first, 266 sbal_number); 267 return retval; 268 } 269 270 /* account for transferred buffers */ 271 atomic_sub(sbal_number, &qdio->req_q_free); 272 qdio->req_q_idx += sbal_number; 273 qdio->req_q_idx %= QDIO_MAX_BUFFERS_PER_Q; 274 275 return 0; 276 } 277 278 279 static void zfcp_qdio_setup_init_data(struct qdio_initialize *id, 280 struct zfcp_qdio *qdio) 281 { 282 memset(id, 0, sizeof(*id)); 283 id->cdev = qdio->adapter->ccw_device; 284 id->q_format = QDIO_ZFCP_QFMT; 285 memcpy(id->adapter_name, dev_name(&id->cdev->dev), 8); 286 ASCEBC(id->adapter_name, 8); 287 id->qib_rflags = QIB_RFLAGS_ENABLE_DATA_DIV; 288 id->no_input_qs = 1; 289 id->no_output_qs = 1; 290 id->input_handler = zfcp_qdio_int_resp; 291 id->output_handler = zfcp_qdio_int_req; 292 id->int_parm = (unsigned long) qdio; 293 id->input_sbal_addr_array = (void **) (qdio->res_q); 294 id->output_sbal_addr_array = (void **) (qdio->req_q); 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); 312 313 return qdio_allocate(&init_data); 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_clear_mask(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 /** 349 * zfcp_qdio_open - prepare and initialize response queue 350 * @qdio: pointer to struct zfcp_qdio 351 * Returns: 0 on success, otherwise -EIO 352 */ 353 int zfcp_qdio_open(struct zfcp_qdio *qdio) 354 { 355 struct qdio_buffer_element *sbale; 356 struct qdio_initialize init_data; 357 struct zfcp_adapter *adapter = qdio->adapter; 358 struct ccw_device *cdev = adapter->ccw_device; 359 struct qdio_ssqd_desc ssqd; 360 int cc; 361 362 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP) 363 return -EIO; 364 365 atomic_clear_mask(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED, 366 &qdio->adapter->status); 367 368 zfcp_qdio_setup_init_data(&init_data, qdio); 369 370 if (qdio_establish(&init_data)) 371 goto failed_establish; 372 373 if (qdio_get_ssqd_desc(init_data.cdev, &ssqd)) 374 goto failed_qdio; 375 376 if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED) 377 atomic_set_mask(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED, 378 &qdio->adapter->status); 379 380 if (qdio_activate(cdev)) 381 goto failed_qdio; 382 383 for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) { 384 sbale = &(qdio->res_q[cc]->element[0]); 385 sbale->length = 0; 386 sbale->flags = SBAL_FLAGS_LAST_ENTRY; 387 sbale->addr = NULL; 388 } 389 390 if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0, QDIO_MAX_BUFFERS_PER_Q)) 391 goto failed_qdio; 392 393 /* set index of first avalable SBALS / number of available SBALS */ 394 qdio->req_q_idx = 0; 395 atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q); 396 397 return 0; 398 399 failed_qdio: 400 qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR); 401 failed_establish: 402 dev_err(&cdev->dev, 403 "Setting up the QDIO connection to the FCP adapter failed\n"); 404 return -EIO; 405 } 406 407 void zfcp_qdio_destroy(struct zfcp_qdio *qdio) 408 { 409 int p; 410 411 if (!qdio) 412 return; 413 414 if (qdio->adapter->ccw_device) 415 qdio_free(qdio->adapter->ccw_device); 416 417 for (p = 0; p < QDIO_MAX_BUFFERS_PER_Q; p += QBUFF_PER_PAGE) { 418 free_page((unsigned long) qdio->req_q[p]); 419 free_page((unsigned long) qdio->res_q[p]); 420 } 421 422 kfree(qdio); 423 } 424 425 int zfcp_qdio_setup(struct zfcp_adapter *adapter) 426 { 427 struct zfcp_qdio *qdio; 428 429 qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL); 430 if (!qdio) 431 return -ENOMEM; 432 433 qdio->adapter = adapter; 434 435 if (zfcp_qdio_allocate(qdio)) { 436 zfcp_qdio_destroy(qdio); 437 return -ENOMEM; 438 } 439 440 spin_lock_init(&qdio->req_q_lock); 441 spin_lock_init(&qdio->stat_lock); 442 443 adapter->qdio = qdio; 444 return 0; 445 } 446 447 /** 448 * zfcp_qdio_siosl - Trigger logging in FCP channel 449 * @adapter: The zfcp_adapter where to trigger logging 450 * 451 * Call the cio siosl function to trigger hardware logging. This 452 * wrapper function sets a flag to ensure hardware logging is only 453 * triggered once before going through qdio shutdown. 454 * 455 * The triggers are always run from qdio tasklet context, so no 456 * additional synchronization is necessary. 457 */ 458 void zfcp_qdio_siosl(struct zfcp_adapter *adapter) 459 { 460 int rc; 461 462 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED) 463 return; 464 465 rc = ccw_device_siosl(adapter->ccw_device); 466 if (!rc) 467 atomic_set_mask(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED, 468 &adapter->status); 469 } 470