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 18static 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 33static 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 47static 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 */ 58static 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 72static 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 92static 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 122static struct qdio_buffer_element * 123zfcp_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 157static struct qdio_buffer_element * 158zfcp_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 */ 174int 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 202static 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 */ 222int 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 */ 252int 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 277static void zfcp_qdio_setup_init_data(struct qdio_initialize *id, 278 struct zfcp_qdio *qdio) 279{ 280 281 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->qib_param_field_format = 0; 287 id->qib_param_field = NULL; 288 id->input_slib_elements = NULL; 289 id->output_slib_elements = NULL; 290 id->no_input_qs = 1; 291 id->no_output_qs = 1; 292 id->input_handler = zfcp_qdio_int_resp; 293 id->output_handler = zfcp_qdio_int_req; 294 id->int_parm = (unsigned long) qdio; 295 id->input_sbal_addr_array = (void **) (qdio->res_q); 296 id->output_sbal_addr_array = (void **) (qdio->req_q); 297} 298 299/** 300 * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data 301 * @adapter: pointer to struct zfcp_adapter 302 * Returns: -ENOMEM on memory allocation error or return value from 303 * qdio_allocate 304 */ 305static int zfcp_qdio_allocate(struct zfcp_qdio *qdio) 306{ 307 struct qdio_initialize init_data; 308 309 if (zfcp_qdio_buffers_enqueue(qdio->req_q) || 310 zfcp_qdio_buffers_enqueue(qdio->res_q)) 311 return -ENOMEM; 312 313 zfcp_qdio_setup_init_data(&init_data, qdio); 314 315 return qdio_allocate(&init_data); 316} 317 318/** 319 * zfcp_close_qdio - close qdio queues for an adapter 320 * @qdio: pointer to structure zfcp_qdio 321 */ 322void zfcp_qdio_close(struct zfcp_qdio *qdio) 323{ 324 struct zfcp_adapter *adapter = qdio->adapter; 325 int idx, count; 326 327 if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)) 328 return; 329 330 /* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */ 331 spin_lock_bh(&qdio->req_q_lock); 332 atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status); 333 spin_unlock_bh(&qdio->req_q_lock); 334 335 wake_up(&qdio->req_q_wq); 336 337 qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR); 338 339 /* cleanup used outbound sbals */ 340 count = atomic_read(&qdio->req_q_free); 341 if (count < QDIO_MAX_BUFFERS_PER_Q) { 342 idx = (qdio->req_q_idx + count) % QDIO_MAX_BUFFERS_PER_Q; 343 count = QDIO_MAX_BUFFERS_PER_Q - count; 344 zfcp_qdio_zero_sbals(qdio->req_q, idx, count); 345 } 346 qdio->req_q_idx = 0; 347 atomic_set(&qdio->req_q_free, 0); 348} 349 350/** 351 * zfcp_qdio_open - prepare and initialize response queue 352 * @qdio: pointer to struct zfcp_qdio 353 * Returns: 0 on success, otherwise -EIO 354 */ 355int zfcp_qdio_open(struct zfcp_qdio *qdio) 356{ 357 struct qdio_buffer_element *sbale; 358 struct qdio_initialize init_data; 359 struct zfcp_adapter *adapter = qdio->adapter; 360 struct ccw_device *cdev = adapter->ccw_device; 361 struct qdio_ssqd_desc ssqd; 362 int cc; 363 364 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP) 365 return -EIO; 366 367 atomic_clear_mask(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED, 368 &qdio->adapter->status); 369 370 zfcp_qdio_setup_init_data(&init_data, qdio); 371 372 if (qdio_establish(&init_data)) 373 goto failed_establish; 374 375 if (qdio_get_ssqd_desc(init_data.cdev, &ssqd)) 376 goto failed_qdio; 377 378 if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED) 379 atomic_set_mask(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED, 380 &qdio->adapter->status); 381 382 if (qdio_activate(cdev)) 383 goto failed_qdio; 384 385 for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) { 386 sbale = &(qdio->res_q[cc]->element[0]); 387 sbale->length = 0; 388 sbale->flags = SBAL_FLAGS_LAST_ENTRY; 389 sbale->addr = NULL; 390 } 391 392 if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0, QDIO_MAX_BUFFERS_PER_Q)) 393 goto failed_qdio; 394 395 /* set index of first avalable SBALS / number of available SBALS */ 396 qdio->req_q_idx = 0; 397 atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q); 398 399 return 0; 400 401failed_qdio: 402 qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR); 403failed_establish: 404 dev_err(&cdev->dev, 405 "Setting up the QDIO connection to the FCP adapter failed\n"); 406 return -EIO; 407} 408 409void 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 427int 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 */ 460void 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