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 spin_lock(&qdio->stat_lock); 64 now = get_clock_monotonic(); 65 span = (now - qdio->req_q_time) >> 12; 66 used = QDIO_MAX_BUFFERS_PER_Q - atomic_read(&qdio->req_q_free); 67 qdio->req_q_util += used * span; 68 qdio->req_q_time = now; 69 spin_unlock(&qdio->stat_lock); 70 } 71 72 static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err, 73 int queue_no, int idx, int count, 74 unsigned long parm) 75 { 76 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm; 77 78 if (unlikely(qdio_err)) { 79 zfcp_dbf_hba_qdio(qdio->adapter->dbf, qdio_err, idx, count); 80 zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err); 81 return; 82 } 83 84 /* cleanup all SBALs being program-owned now */ 85 zfcp_qdio_zero_sbals(qdio->req_q, idx, count); 86 87 zfcp_qdio_account(qdio); 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_bh(&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_bh(&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_bh(&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_bh(&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 zfcp_qdio_account(qdio); 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 } 294 295 /** 296 * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data 297 * @adapter: pointer to struct zfcp_adapter 298 * Returns: -ENOMEM on memory allocation error or return value from 299 * qdio_allocate 300 */ 301 static int zfcp_qdio_allocate(struct zfcp_qdio *qdio) 302 { 303 struct qdio_initialize init_data; 304 305 if (zfcp_qdio_buffers_enqueue(qdio->req_q) || 306 zfcp_qdio_buffers_enqueue(qdio->res_q)) 307 return -ENOMEM; 308 309 zfcp_qdio_setup_init_data(&init_data, qdio); 310 311 return qdio_allocate(&init_data); 312 } 313 314 /** 315 * zfcp_close_qdio - close qdio queues for an adapter 316 * @qdio: pointer to structure zfcp_qdio 317 */ 318 void zfcp_qdio_close(struct zfcp_qdio *qdio) 319 { 320 struct zfcp_adapter *adapter = qdio->adapter; 321 int idx, count; 322 323 if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 324 return; 325 326 /* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */ 327 spin_lock_bh(&qdio->req_q_lock); 328 atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status); 329 spin_unlock_bh(&qdio->req_q_lock); 330 331 wake_up(&qdio->req_q_wq); 332 333 qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR); 334 335 /* cleanup used outbound sbals */ 336 count = atomic_read(&qdio->req_q_free); 337 if (count < QDIO_MAX_BUFFERS_PER_Q) { 338 idx = (qdio->req_q_idx + count) % QDIO_MAX_BUFFERS_PER_Q; 339 count = QDIO_MAX_BUFFERS_PER_Q - count; 340 zfcp_qdio_zero_sbals(qdio->req_q, idx, count); 341 } 342 qdio->req_q_idx = 0; 343 atomic_set(&qdio->req_q_free, 0); 344 } 345 346 /** 347 * zfcp_qdio_open - prepare and initialize response queue 348 * @qdio: pointer to struct zfcp_qdio 349 * Returns: 0 on success, otherwise -EIO 350 */ 351 int zfcp_qdio_open(struct zfcp_qdio *qdio) 352 { 353 struct qdio_buffer_element *sbale; 354 struct qdio_initialize init_data; 355 struct zfcp_adapter *adapter = qdio->adapter; 356 struct ccw_device *cdev = adapter->ccw_device; 357 struct qdio_ssqd_desc ssqd; 358 int cc; 359 360 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP) 361 return -EIO; 362 363 atomic_clear_mask(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED, 364 &qdio->adapter->status); 365 366 zfcp_qdio_setup_init_data(&init_data, qdio); 367 368 if (qdio_establish(&init_data)) 369 goto failed_establish; 370 371 if (qdio_get_ssqd_desc(init_data.cdev, &ssqd)) 372 goto failed_qdio; 373 374 if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED) 375 atomic_set_mask(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED, 376 &qdio->adapter->status); 377 378 if (qdio_activate(cdev)) 379 goto failed_qdio; 380 381 for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) { 382 sbale = &(qdio->res_q[cc]->element[0]); 383 sbale->length = 0; 384 sbale->flags = SBAL_FLAGS_LAST_ENTRY; 385 sbale->addr = NULL; 386 } 387 388 if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0, QDIO_MAX_BUFFERS_PER_Q)) 389 goto failed_qdio; 390 391 /* set index of first avalable SBALS / number of available SBALS */ 392 qdio->req_q_idx = 0; 393 atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q); 394 395 return 0; 396 397 failed_qdio: 398 qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR); 399 failed_establish: 400 dev_err(&cdev->dev, 401 "Setting up the QDIO connection to the FCP adapter failed\n"); 402 return -EIO; 403 } 404 405 void zfcp_qdio_destroy(struct zfcp_qdio *qdio) 406 { 407 int p; 408 409 if (!qdio) 410 return; 411 412 if (qdio->adapter->ccw_device) 413 qdio_free(qdio->adapter->ccw_device); 414 415 for (p = 0; p < QDIO_MAX_BUFFERS_PER_Q; p += QBUFF_PER_PAGE) { 416 free_page((unsigned long) qdio->req_q[p]); 417 free_page((unsigned long) qdio->res_q[p]); 418 } 419 420 kfree(qdio); 421 } 422 423 int zfcp_qdio_setup(struct zfcp_adapter *adapter) 424 { 425 struct zfcp_qdio *qdio; 426 427 qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL); 428 if (!qdio) 429 return -ENOMEM; 430 431 qdio->adapter = adapter; 432 433 if (zfcp_qdio_allocate(qdio)) { 434 zfcp_qdio_destroy(qdio); 435 return -ENOMEM; 436 } 437 438 spin_lock_init(&qdio->req_q_lock); 439 spin_lock_init(&qdio->stat_lock); 440 441 adapter->qdio = qdio; 442 return 0; 443 } 444 445 /** 446 * zfcp_qdio_siosl - Trigger logging in FCP channel 447 * @adapter: The zfcp_adapter where to trigger logging 448 * 449 * Call the cio siosl function to trigger hardware logging. This 450 * wrapper function sets a flag to ensure hardware logging is only 451 * triggered once before going through qdio shutdown. 452 * 453 * The triggers are always run from qdio tasklet context, so no 454 * additional synchronization is necessary. 455 */ 456 void zfcp_qdio_siosl(struct zfcp_adapter *adapter) 457 { 458 int rc; 459 460 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED) 461 return; 462 463 rc = ccw_device_siosl(adapter->ccw_device); 464 if (!rc) 465 atomic_set_mask(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED, 466 &adapter->status); 467 } 468