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1// SPDX-License-Identifier: GPL-2.02/*3 * zfcp device driver4 *5 * Setup and helper functions to access QDIO.6 *7 * Copyright IBM Corp. 2002, 20208 */9 10#define KMSG_COMPONENT "zfcp"11#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt12 13#include <linux/lockdep.h>14#include <linux/slab.h>15#include <linux/module.h>16#include "zfcp_ext.h"17#include "zfcp_qdio.h"18 19static bool enable_multibuffer = true;20module_param_named(datarouter, enable_multibuffer, bool, 0400);21MODULE_PARM_DESC(datarouter, "Enable hardware data router support (default on)");22 23#define ZFCP_QDIO_REQUEST_RESCAN_MSECS (MSEC_PER_SEC * 10)24#define ZFCP_QDIO_REQUEST_SCAN_MSECS MSEC_PER_SEC25 26static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *dbftag,27 unsigned int qdio_err)28{29 struct zfcp_adapter *adapter = qdio->adapter;30 31 dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n");32 33 if (qdio_err & QDIO_ERROR_SLSB_STATE) {34 zfcp_qdio_siosl(adapter);35 zfcp_erp_adapter_shutdown(adapter, 0, dbftag);36 return;37 }38 zfcp_erp_adapter_reopen(adapter,39 ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED |40 ZFCP_STATUS_COMMON_ERP_FAILED, dbftag);41}42 43static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt)44{45 int i, sbal_idx;46 47 for (i = first; i < first + cnt; i++) {48 sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q;49 memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer));50 }51}52 53/* this needs to be called prior to updating the queue fill level */54static inline void zfcp_qdio_account(struct zfcp_qdio *qdio)55{56 unsigned long long now, span;57 int used;58 59 now = get_tod_clock_monotonic();60 span = (now - qdio->req_q_time) >> 12;61 used = QDIO_MAX_BUFFERS_PER_Q - atomic_read(&qdio->req_q_free);62 qdio->req_q_util += used * span;63 qdio->req_q_time = now;64}65 66static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err,67 int queue_no, int idx, int count,68 unsigned long parm)69{70 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;71 72 zfcp_qdio_handler_error(qdio, "qdireq1", qdio_err);73}74 75static void zfcp_qdio_request_tasklet(struct tasklet_struct *tasklet)76{77 struct zfcp_qdio *qdio = from_tasklet(qdio, tasklet, request_tasklet);78 struct ccw_device *cdev = qdio->adapter->ccw_device;79 unsigned int start, error;80 int completed;81 82 completed = qdio_inspect_output_queue(cdev, 0, &start, &error);83 if (completed > 0) {84 if (error) {85 zfcp_qdio_handler_error(qdio, "qdreqt1", error);86 } else {87 /* cleanup all SBALs being program-owned now */88 zfcp_qdio_zero_sbals(qdio->req_q, start, completed);89 90 spin_lock_irq(&qdio->stat_lock);91 zfcp_qdio_account(qdio);92 spin_unlock_irq(&qdio->stat_lock);93 atomic_add(completed, &qdio->req_q_free);94 wake_up(&qdio->req_q_wq);95 }96 }97 98 if (atomic_read(&qdio->req_q_free) < QDIO_MAX_BUFFERS_PER_Q)99 timer_reduce(&qdio->request_timer,100 jiffies + msecs_to_jiffies(ZFCP_QDIO_REQUEST_RESCAN_MSECS));101}102 103static void zfcp_qdio_request_timer(struct timer_list *timer)104{105 struct zfcp_qdio *qdio = from_timer(qdio, timer, request_timer);106 107 tasklet_schedule(&qdio->request_tasklet);108}109 110static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,111 int queue_no, int idx, int count,112 unsigned long parm)113{114 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;115 struct zfcp_adapter *adapter = qdio->adapter;116 int sbal_no, sbal_idx;117 118 if (unlikely(qdio_err)) {119 if (zfcp_adapter_multi_buffer_active(adapter)) {120 void *pl[ZFCP_QDIO_MAX_SBALS_PER_REQ + 1];121 struct qdio_buffer_element *sbale;122 u64 req_id;123 u8 scount;124 125 memset(pl, 0,126 ZFCP_QDIO_MAX_SBALS_PER_REQ * sizeof(void *));127 sbale = qdio->res_q[idx]->element;128 req_id = dma64_to_u64(sbale->addr);129 scount = min(sbale->scount + 1,130 ZFCP_QDIO_MAX_SBALS_PER_REQ + 1);131 /* incl. signaling SBAL */132 133 for (sbal_no = 0; sbal_no < scount; sbal_no++) {134 sbal_idx = (idx + sbal_no) %135 QDIO_MAX_BUFFERS_PER_Q;136 pl[sbal_no] = qdio->res_q[sbal_idx];137 }138 zfcp_dbf_hba_def_err(adapter, req_id, scount, pl);139 }140 zfcp_qdio_handler_error(qdio, "qdires1", qdio_err);141 return;142 }143 144 /*145 * go through all SBALs from input queue currently146 * returned by QDIO layer147 */148 for (sbal_no = 0; sbal_no < count; sbal_no++) {149 sbal_idx = (idx + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;150 /* go through all SBALEs of SBAL */151 zfcp_fsf_reqid_check(qdio, sbal_idx);152 }153 154 /*155 * put SBALs back to response queue156 */157 if (qdio_add_bufs_to_input_queue(cdev, 0, idx, count))158 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdires2");159}160 161static void zfcp_qdio_irq_tasklet(struct tasklet_struct *tasklet)162{163 struct zfcp_qdio *qdio = from_tasklet(qdio, tasklet, irq_tasklet);164 struct ccw_device *cdev = qdio->adapter->ccw_device;165 unsigned int start, error;166 int completed;167 168 if (atomic_read(&qdio->req_q_free) < QDIO_MAX_BUFFERS_PER_Q)169 tasklet_schedule(&qdio->request_tasklet);170 171 /* Check the Response Queue: */172 completed = qdio_inspect_input_queue(cdev, 0, &start, &error);173 if (completed < 0)174 return;175 if (completed > 0)176 zfcp_qdio_int_resp(cdev, error, 0, start, completed,177 (unsigned long) qdio);178 179 if (qdio_start_irq(cdev))180 /* More work pending: */181 tasklet_schedule(&qdio->irq_tasklet);182}183 184static void zfcp_qdio_poll(struct ccw_device *cdev, unsigned long data)185{186 struct zfcp_qdio *qdio = (struct zfcp_qdio *) data;187 188 tasklet_schedule(&qdio->irq_tasklet);189}190 191static struct qdio_buffer_element *192zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)193{194 struct qdio_buffer_element *sbale;195 196 /* set last entry flag in current SBALE of current SBAL */197 sbale = zfcp_qdio_sbale_curr(qdio, q_req);198 sbale->eflags |= SBAL_EFLAGS_LAST_ENTRY;199 200 /* don't exceed last allowed SBAL */201 if (q_req->sbal_last == q_req->sbal_limit)202 return NULL;203 204 /* set chaining flag in first SBALE of current SBAL */205 sbale = zfcp_qdio_sbale_req(qdio, q_req);206 sbale->sflags |= SBAL_SFLAGS0_MORE_SBALS;207 208 /* calculate index of next SBAL */209 q_req->sbal_last++;210 q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q;211 212 /* keep this requests number of SBALs up-to-date */213 q_req->sbal_number++;214 BUG_ON(q_req->sbal_number > ZFCP_QDIO_MAX_SBALS_PER_REQ);215 216 /* start at first SBALE of new SBAL */217 q_req->sbale_curr = 0;218 219 /* set storage-block type for new SBAL */220 sbale = zfcp_qdio_sbale_curr(qdio, q_req);221 sbale->sflags |= q_req->sbtype;222 223 return sbale;224}225 226static struct qdio_buffer_element *227zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)228{229 if (q_req->sbale_curr == qdio->max_sbale_per_sbal - 1)230 return zfcp_qdio_sbal_chain(qdio, q_req);231 q_req->sbale_curr++;232 return zfcp_qdio_sbale_curr(qdio, q_req);233}234 235/**236 * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list237 * @qdio: pointer to struct zfcp_qdio238 * @q_req: pointer to struct zfcp_qdio_req239 * @sg: scatter-gather list240 * Returns: zero or -EINVAL on error241 */242int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,243 struct scatterlist *sg)244{245 struct qdio_buffer_element *sbale;246 247 /* set storage-block type for this request */248 sbale = zfcp_qdio_sbale_req(qdio, q_req);249 sbale->sflags |= q_req->sbtype;250 251 for (; sg; sg = sg_next(sg)) {252 sbale = zfcp_qdio_sbale_next(qdio, q_req);253 if (!sbale) {254 atomic_inc(&qdio->req_q_full);255 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,256 q_req->sbal_number);257 return -EINVAL;258 }259 sbale->addr = u64_to_dma64(sg_phys(sg));260 sbale->length = sg->length;261 }262 return 0;263}264 265static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio)266{267 if (atomic_read(&qdio->req_q_free) ||268 !(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))269 return 1;270 return 0;271}272 273/**274 * zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary275 * @qdio: pointer to struct zfcp_qdio276 *277 * The req_q_lock must be held by the caller of this function, and278 * this function may only be called from process context; it will279 * sleep when waiting for a free sbal.280 *281 * Returns: 0 on success, -EIO if there is no free sbal after waiting.282 */283int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio)284{285 long ret;286 287 ret = wait_event_interruptible_lock_irq_timeout(qdio->req_q_wq,288 zfcp_qdio_sbal_check(qdio), qdio->req_q_lock, 5 * HZ);289 290 if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))291 return -EIO;292 293 if (ret > 0)294 return 0;295 296 if (!ret) {297 atomic_inc(&qdio->req_q_full);298 /* assume hanging outbound queue, try queue recovery */299 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1");300 }301 302 return -EIO;303}304 305/**306 * zfcp_qdio_send - send req to QDIO307 * @qdio: pointer to struct zfcp_qdio308 * @q_req: pointer to struct zfcp_qdio_req309 * Returns: 0 on success, error otherwise310 */311int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)312{313 int retval;314 u8 sbal_number = q_req->sbal_number;315 316 /*317 * This should actually be a spin_lock_bh(stat_lock), to protect against318 * Request Queue completion processing in tasklet context.319 * But we can't do so (and are safe), as we always get called with IRQs320 * disabled by spin_lock_irq[save](req_q_lock).321 */322 lockdep_assert_irqs_disabled();323 spin_lock(&qdio->stat_lock);324 zfcp_qdio_account(qdio);325 spin_unlock(&qdio->stat_lock);326 327 atomic_sub(sbal_number, &qdio->req_q_free);328 329 retval = qdio_add_bufs_to_output_queue(qdio->adapter->ccw_device, 0,330 q_req->sbal_first, sbal_number,331 NULL);332 333 if (unlikely(retval)) {334 /* Failed to submit the IO, roll back our modifications. */335 atomic_add(sbal_number, &qdio->req_q_free);336 zfcp_qdio_zero_sbals(qdio->req_q, q_req->sbal_first,337 sbal_number);338 return retval;339 }340 341 if (atomic_read(&qdio->req_q_free) <= 2 * ZFCP_QDIO_MAX_SBALS_PER_REQ)342 tasklet_schedule(&qdio->request_tasklet);343 else344 timer_reduce(&qdio->request_timer,345 jiffies + msecs_to_jiffies(ZFCP_QDIO_REQUEST_SCAN_MSECS));346 347 /* account for transferred buffers */348 qdio->req_q_idx += sbal_number;349 qdio->req_q_idx %= QDIO_MAX_BUFFERS_PER_Q;350 351 return 0;352}353 354/**355 * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data356 * @qdio: pointer to struct zfcp_qdio357 * Returns: -ENOMEM on memory allocation error or return value from358 * qdio_allocate359 */360static int zfcp_qdio_allocate(struct zfcp_qdio *qdio)361{362 int ret;363 364 ret = qdio_alloc_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);365 if (ret)366 return -ENOMEM;367 368 ret = qdio_alloc_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);369 if (ret)370 goto free_req_q;371 372 init_waitqueue_head(&qdio->req_q_wq);373 374 ret = qdio_allocate(qdio->adapter->ccw_device, 1, 1);375 if (ret)376 goto free_res_q;377 378 return 0;379 380free_res_q:381 qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);382free_req_q:383 qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);384 return ret;385}386 387/**388 * zfcp_qdio_close - close qdio queues for an adapter389 * @qdio: pointer to structure zfcp_qdio390 */391void zfcp_qdio_close(struct zfcp_qdio *qdio)392{393 struct zfcp_adapter *adapter = qdio->adapter;394 int idx, count;395 396 if (!(atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))397 return;398 399 /*400 * Clear QDIOUP flag, thus qdio_add_bufs_to_output_queue() is not called401 * during qdio_shutdown().402 */403 spin_lock_irq(&qdio->req_q_lock);404 atomic_andnot(ZFCP_STATUS_ADAPTER_QDIOUP, &adapter->status);405 spin_unlock_irq(&qdio->req_q_lock);406 407 wake_up(&qdio->req_q_wq);408 409 tasklet_disable(&qdio->irq_tasklet);410 tasklet_disable(&qdio->request_tasklet);411 del_timer_sync(&qdio->request_timer);412 qdio_stop_irq(adapter->ccw_device);413 qdio_shutdown(adapter->ccw_device, QDIO_FLAG_CLEANUP_USING_CLEAR);414 415 /* cleanup used outbound sbals */416 count = atomic_read(&qdio->req_q_free);417 if (count < QDIO_MAX_BUFFERS_PER_Q) {418 idx = (qdio->req_q_idx + count) % QDIO_MAX_BUFFERS_PER_Q;419 count = QDIO_MAX_BUFFERS_PER_Q - count;420 zfcp_qdio_zero_sbals(qdio->req_q, idx, count);421 }422 qdio->req_q_idx = 0;423 atomic_set(&qdio->req_q_free, 0);424}425 426void zfcp_qdio_shost_update(struct zfcp_adapter *const adapter,427 const struct zfcp_qdio *const qdio)428{429 struct Scsi_Host *const shost = adapter->scsi_host;430 431 if (shost == NULL)432 return;433 434 shost->sg_tablesize = qdio->max_sbale_per_req;435 shost->max_sectors = qdio->max_sbale_per_req * 8;436}437 438/**439 * zfcp_qdio_open - prepare and initialize response queue440 * @qdio: pointer to struct zfcp_qdio441 * Returns: 0 on success, otherwise -EIO442 */443int zfcp_qdio_open(struct zfcp_qdio *qdio)444{445 struct qdio_buffer **input_sbals[1] = {qdio->res_q};446 struct qdio_buffer **output_sbals[1] = {qdio->req_q};447 struct qdio_buffer_element *sbale;448 struct qdio_initialize init_data = {0};449 struct zfcp_adapter *adapter = qdio->adapter;450 struct ccw_device *cdev = adapter->ccw_device;451 struct qdio_ssqd_desc ssqd;452 int cc;453 454 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)455 return -EIO;456 457 atomic_andnot(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,458 &qdio->adapter->status);459 460 init_data.q_format = QDIO_ZFCP_QFMT;461 init_data.qib_rflags = QIB_RFLAGS_ENABLE_DATA_DIV;462 if (enable_multibuffer)463 init_data.qdr_ac |= QDR_AC_MULTI_BUFFER_ENABLE;464 init_data.no_input_qs = 1;465 init_data.no_output_qs = 1;466 init_data.input_handler = zfcp_qdio_int_resp;467 init_data.output_handler = zfcp_qdio_int_req;468 init_data.irq_poll = zfcp_qdio_poll;469 init_data.int_parm = (unsigned long) qdio;470 init_data.input_sbal_addr_array = input_sbals;471 init_data.output_sbal_addr_array = output_sbals;472 473 if (qdio_establish(cdev, &init_data))474 goto failed_establish;475 476 if (qdio_get_ssqd_desc(cdev, &ssqd))477 goto failed_qdio;478 479 if (ssqd.qdioac2 & CHSC_AC2_DATA_DIV_ENABLED)480 atomic_or(ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED,481 &qdio->adapter->status);482 483 if (ssqd.qdioac2 & CHSC_AC2_MULTI_BUFFER_ENABLED) {484 atomic_or(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);485 qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER;486 } else {487 atomic_andnot(ZFCP_STATUS_ADAPTER_MB_ACT, &adapter->status);488 qdio->max_sbale_per_sbal = QDIO_MAX_ELEMENTS_PER_BUFFER - 1;489 }490 491 qdio->max_sbale_per_req =492 ZFCP_QDIO_MAX_SBALS_PER_REQ * qdio->max_sbale_per_sbal493 - 2;494 if (qdio_activate(cdev))495 goto failed_qdio;496 497 for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) {498 sbale = &(qdio->res_q[cc]->element[0]);499 sbale->length = 0;500 sbale->eflags = SBAL_EFLAGS_LAST_ENTRY;501 sbale->sflags = 0;502 sbale->addr = 0;503 }504 505 if (qdio_add_bufs_to_input_queue(cdev, 0, 0, QDIO_MAX_BUFFERS_PER_Q))506 goto failed_qdio;507 508 /* set index of first available SBALS / number of available SBALS */509 qdio->req_q_idx = 0;510 atomic_set(&qdio->req_q_free, QDIO_MAX_BUFFERS_PER_Q);511 atomic_or(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status);512 513 /* Enable processing for Request Queue completions: */514 tasklet_enable(&qdio->request_tasklet);515 /* Enable processing for QDIO interrupts: */516 tasklet_enable(&qdio->irq_tasklet);517 /* This results in a qdio_start_irq(): */518 tasklet_schedule(&qdio->irq_tasklet);519 520 zfcp_qdio_shost_update(adapter, qdio);521 522 return 0;523 524failed_qdio:525 qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);526failed_establish:527 dev_err(&cdev->dev,528 "Setting up the QDIO connection to the FCP adapter failed\n");529 return -EIO;530}531 532void zfcp_qdio_destroy(struct zfcp_qdio *qdio)533{534 if (!qdio)535 return;536 537 tasklet_kill(&qdio->irq_tasklet);538 tasklet_kill(&qdio->request_tasklet);539 540 if (qdio->adapter->ccw_device)541 qdio_free(qdio->adapter->ccw_device);542 543 qdio_free_buffers(qdio->req_q, QDIO_MAX_BUFFERS_PER_Q);544 qdio_free_buffers(qdio->res_q, QDIO_MAX_BUFFERS_PER_Q);545 kfree(qdio);546}547 548int zfcp_qdio_setup(struct zfcp_adapter *adapter)549{550 struct zfcp_qdio *qdio;551 552 qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL);553 if (!qdio)554 return -ENOMEM;555 556 qdio->adapter = adapter;557 558 if (zfcp_qdio_allocate(qdio)) {559 kfree(qdio);560 return -ENOMEM;561 }562 563 spin_lock_init(&qdio->req_q_lock);564 spin_lock_init(&qdio->stat_lock);565 timer_setup(&qdio->request_timer, zfcp_qdio_request_timer, 0);566 tasklet_setup(&qdio->irq_tasklet, zfcp_qdio_irq_tasklet);567 tasklet_setup(&qdio->request_tasklet, zfcp_qdio_request_tasklet);568 tasklet_disable(&qdio->irq_tasklet);569 tasklet_disable(&qdio->request_tasklet);570 571 adapter->qdio = qdio;572 return 0;573}574 575/**576 * zfcp_qdio_siosl - Trigger logging in FCP channel577 * @adapter: The zfcp_adapter where to trigger logging578 *579 * Call the cio siosl function to trigger hardware logging. This580 * wrapper function sets a flag to ensure hardware logging is only581 * triggered once before going through qdio shutdown.582 *583 * The triggers are always run from qdio tasklet context, so no584 * additional synchronization is necessary.585 */586void zfcp_qdio_siosl(struct zfcp_adapter *adapter)587{588 int rc;589 590 if (atomic_read(&adapter->status) & ZFCP_STATUS_ADAPTER_SIOSL_ISSUED)591 return;592 593 rc = ccw_device_siosl(adapter->ccw_device);594 if (!rc)595 atomic_or(ZFCP_STATUS_ADAPTER_SIOSL_ISSUED,596 &adapter->status);597}598