4 * Setup and helper functions to access QDIO.
6 * Copyright IBM Corporation 2002, 2009
9 #define KMSG_COMPONENT "zfcp"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
14 #define QBUFF_PER_PAGE (PAGE_SIZE / sizeof(struct qdio_buffer))
16 static int zfcp_qdio_buffers_enqueue(struct qdio_buffer **sbal)
20 for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos += QBUFF_PER_PAGE) {
21 sbal[pos] = (struct qdio_buffer *) get_zeroed_page(GFP_KERNEL);
25 for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos++)
26 if (pos % QBUFF_PER_PAGE)
27 sbal[pos] = sbal[pos - 1] + 1;
31 static struct qdio_buffer_element *
32 zfcp_qdio_sbale(struct zfcp_qdio_queue *q, int sbal_idx, int sbale_idx)
34 return &q->sbal[sbal_idx]->element[sbale_idx];
38 * zfcp_qdio_free - free memory used by request- and resposne queue
39 * @qdio: pointer to the zfcp_qdio structure
41 void zfcp_qdio_free(struct zfcp_qdio *qdio)
43 struct qdio_buffer **sbal_req, **sbal_resp;
46 if (qdio->adapter->ccw_device)
47 qdio_free(qdio->adapter->ccw_device);
49 sbal_req = qdio->req_q.sbal;
50 sbal_resp = qdio->resp_q.sbal;
52 for (p = 0; p < QDIO_MAX_BUFFERS_PER_Q; p += QBUFF_PER_PAGE) {
53 free_page((unsigned long) sbal_req[p]);
54 free_page((unsigned long) sbal_resp[p]);
58 static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *id)
60 struct zfcp_adapter *adapter = qdio->adapter;
62 dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n");
64 zfcp_erp_adapter_reopen(adapter,
65 ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED |
66 ZFCP_STATUS_COMMON_ERP_FAILED, id, NULL);
69 static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt)
73 for (i = first; i < first + cnt; i++) {
74 sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q;
75 memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer));
79 /* this needs to be called prior to updating the queue fill level */
80 static void zfcp_qdio_account(struct zfcp_qdio *qdio)
86 spin_lock(&qdio->stat_lock);
88 span = ktime_us_delta(now, qdio->req_q_time);
89 free = max(0, atomic_read(&qdio->req_q.count));
90 used = QDIO_MAX_BUFFERS_PER_Q - free;
91 qdio->req_q_util += used * span;
92 qdio->req_q_time = now;
93 spin_unlock(&qdio->stat_lock);
96 static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err,
97 int queue_no, int first, int count,
100 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
101 struct zfcp_qdio_queue *queue = &qdio->req_q;
103 if (unlikely(qdio_err)) {
104 zfcp_hba_dbf_event_qdio(qdio, qdio_err, first, count);
105 zfcp_qdio_handler_error(qdio, "qdireq1");
109 /* cleanup all SBALs being program-owned now */
110 zfcp_qdio_zero_sbals(queue->sbal, first, count);
112 zfcp_qdio_account(qdio);
113 atomic_add(count, &queue->count);
114 wake_up(&qdio->req_q_wq);
117 static void zfcp_qdio_resp_put_back(struct zfcp_qdio *qdio, int processed)
119 struct zfcp_qdio_queue *queue = &qdio->resp_q;
120 struct ccw_device *cdev = qdio->adapter->ccw_device;
121 u8 count, start = queue->first;
124 count = atomic_read(&queue->count) + processed;
126 retval = do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, start, count);
128 if (unlikely(retval)) {
129 atomic_set(&queue->count, count);
130 /* FIXME: Recover this with an adapter reopen? */
132 queue->first += count;
133 queue->first %= QDIO_MAX_BUFFERS_PER_Q;
134 atomic_set(&queue->count, 0);
138 static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
139 int queue_no, int first, int count,
142 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
143 int sbal_idx, sbal_no;
145 if (unlikely(qdio_err)) {
146 zfcp_hba_dbf_event_qdio(qdio, qdio_err, first, count);
147 zfcp_qdio_handler_error(qdio, "qdires1");
152 * go through all SBALs from input queue currently
153 * returned by QDIO layer
155 for (sbal_no = 0; sbal_no < count; sbal_no++) {
156 sbal_idx = (first + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;
157 /* go through all SBALEs of SBAL */
158 zfcp_fsf_reqid_check(qdio, sbal_idx);
162 * put range of SBALs back to response queue
163 * (including SBALs which have already been free before)
165 zfcp_qdio_resp_put_back(qdio, count);
169 * zfcp_qdio_sbale_req - return ptr to SBALE of req_q for a struct zfcp_fsf_req
170 * @qdio: pointer to struct zfcp_qdio
171 * @q_rec: pointer to struct zfcp_queue_rec
172 * Returns: pointer to qdio_buffer_element (SBALE) structure
174 struct qdio_buffer_element *zfcp_qdio_sbale_req(struct zfcp_qdio *qdio,
175 struct zfcp_queue_req *q_req)
177 return zfcp_qdio_sbale(&qdio->req_q, q_req->sbal_last, 0);
181 * zfcp_qdio_sbale_curr - return curr SBALE on req_q for a struct zfcp_fsf_req
182 * @fsf_req: pointer to struct fsf_req
183 * Returns: pointer to qdio_buffer_element (SBALE) structure
185 struct qdio_buffer_element *zfcp_qdio_sbale_curr(struct zfcp_qdio *qdio,
186 struct zfcp_queue_req *q_req)
188 return zfcp_qdio_sbale(&qdio->req_q, q_req->sbal_last,
192 static void zfcp_qdio_sbal_limit(struct zfcp_qdio *qdio,
193 struct zfcp_queue_req *q_req, int max_sbals)
195 int count = atomic_read(&qdio->req_q.count);
196 count = min(count, max_sbals);
197 q_req->sbal_limit = (q_req->sbal_first + count - 1)
198 % QDIO_MAX_BUFFERS_PER_Q;
201 static struct qdio_buffer_element *
202 zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_queue_req *q_req,
203 unsigned long sbtype)
205 struct qdio_buffer_element *sbale;
207 /* set last entry flag in current SBALE of current SBAL */
208 sbale = zfcp_qdio_sbale_curr(qdio, q_req);
209 sbale->flags |= SBAL_FLAGS_LAST_ENTRY;
211 /* don't exceed last allowed SBAL */
212 if (q_req->sbal_last == q_req->sbal_limit)
215 /* set chaining flag in first SBALE of current SBAL */
216 sbale = zfcp_qdio_sbale_req(qdio, q_req);
217 sbale->flags |= SBAL_FLAGS0_MORE_SBALS;
219 /* calculate index of next SBAL */
221 q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q;
223 /* keep this requests number of SBALs up-to-date */
224 q_req->sbal_number++;
226 /* start at first SBALE of new SBAL */
227 q_req->sbale_curr = 0;
229 /* set storage-block type for new SBAL */
230 sbale = zfcp_qdio_sbale_curr(qdio, q_req);
231 sbale->flags |= sbtype;
236 static struct qdio_buffer_element *
237 zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_queue_req *q_req,
240 if (q_req->sbale_curr == ZFCP_LAST_SBALE_PER_SBAL)
241 return zfcp_qdio_sbal_chain(qdio, q_req, sbtype);
243 return zfcp_qdio_sbale_curr(qdio, q_req);
246 static void zfcp_qdio_undo_sbals(struct zfcp_qdio *qdio,
247 struct zfcp_queue_req *q_req)
249 struct qdio_buffer **sbal = qdio->req_q.sbal;
250 int first = q_req->sbal_first;
251 int last = q_req->sbal_last;
252 int count = (last - first + QDIO_MAX_BUFFERS_PER_Q) %
253 QDIO_MAX_BUFFERS_PER_Q + 1;
254 zfcp_qdio_zero_sbals(sbal, first, count);
257 static int zfcp_qdio_fill_sbals(struct zfcp_qdio *qdio,
258 struct zfcp_queue_req *q_req,
259 unsigned int sbtype, void *start_addr,
260 unsigned int total_length)
262 struct qdio_buffer_element *sbale;
263 unsigned long remaining, length;
266 /* split segment up */
267 for (addr = start_addr, remaining = total_length; remaining > 0;
268 addr += length, remaining -= length) {
269 sbale = zfcp_qdio_sbale_next(qdio, q_req, sbtype);
271 atomic_inc(&qdio->req_q_full);
272 zfcp_qdio_undo_sbals(qdio, q_req);
276 /* new piece must not exceed next page boundary */
277 length = min(remaining,
278 (PAGE_SIZE - ((unsigned long)addr &
281 sbale->length = length;
287 * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
288 * @fsf_req: request to be processed
289 * @sbtype: SBALE flags
290 * @sg: scatter-gather list
291 * @max_sbals: upper bound for number of SBALs to be used
292 * Returns: number of bytes, or error (negativ)
294 int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio,
295 struct zfcp_queue_req *q_req,
296 unsigned long sbtype, struct scatterlist *sg,
299 struct qdio_buffer_element *sbale;
300 int retval, bytes = 0;
302 /* figure out last allowed SBAL */
303 zfcp_qdio_sbal_limit(qdio, q_req, max_sbals);
305 /* set storage-block type for this request */
306 sbale = zfcp_qdio_sbale_req(qdio, q_req);
307 sbale->flags |= sbtype;
309 for (; sg; sg = sg_next(sg)) {
310 retval = zfcp_qdio_fill_sbals(qdio, q_req, sbtype,
311 sg_virt(sg), sg->length);
317 /* assume that no other SBALEs are to follow in the same SBAL */
318 sbale = zfcp_qdio_sbale_curr(qdio, q_req);
319 sbale->flags |= SBAL_FLAGS_LAST_ENTRY;
325 * zfcp_qdio_send - set PCI flag in first SBALE and send req to QDIO
326 * @qdio: pointer to struct zfcp_qdio
327 * @q_req: pointer to struct zfcp_queue_req
328 * Returns: 0 on success, error otherwise
330 int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_queue_req *q_req)
332 struct zfcp_qdio_queue *req_q = &qdio->req_q;
333 int first = q_req->sbal_first;
334 int count = q_req->sbal_number;
336 unsigned int qdio_flags = QDIO_FLAG_SYNC_OUTPUT;
338 zfcp_qdio_account(qdio);
340 retval = do_QDIO(qdio->adapter->ccw_device, qdio_flags, 0, first,
342 if (unlikely(retval)) {
343 zfcp_qdio_zero_sbals(req_q->sbal, first, count);
347 /* account for transferred buffers */
348 atomic_sub(count, &req_q->count);
349 req_q->first += count;
350 req_q->first %= QDIO_MAX_BUFFERS_PER_Q;
355 static void zfcp_qdio_setup_init_data(struct qdio_initialize *id,
356 struct zfcp_qdio *qdio)
359 id->cdev = qdio->adapter->ccw_device;
360 id->q_format = QDIO_ZFCP_QFMT;
361 memcpy(id->adapter_name, dev_name(&id->cdev->dev), 8);
362 ASCEBC(id->adapter_name, 8);
363 id->qib_param_field_format = 0;
364 id->qib_param_field = NULL;
365 id->input_slib_elements = NULL;
366 id->output_slib_elements = NULL;
368 id->no_output_qs = 1;
369 id->input_handler = zfcp_qdio_int_resp;
370 id->output_handler = zfcp_qdio_int_req;
371 id->int_parm = (unsigned long) qdio;
372 id->flags = QDIO_INBOUND_0COPY_SBALS |
373 QDIO_OUTBOUND_0COPY_SBALS | QDIO_USE_OUTBOUND_PCIS;
374 id->input_sbal_addr_array = (void **) (qdio->resp_q.sbal);
375 id->output_sbal_addr_array = (void **) (qdio->req_q.sbal);
379 * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data
380 * @adapter: pointer to struct zfcp_adapter
381 * Returns: -ENOMEM on memory allocation error or return value from
384 int zfcp_qdio_allocate(struct zfcp_qdio *qdio, struct ccw_device *ccw_dev)
386 struct qdio_initialize init_data;
388 if (zfcp_qdio_buffers_enqueue(qdio->req_q.sbal) ||
389 zfcp_qdio_buffers_enqueue(qdio->resp_q.sbal))
392 zfcp_qdio_setup_init_data(&init_data, qdio);
394 return qdio_allocate(&init_data);
398 * zfcp_close_qdio - close qdio queues for an adapter
399 * @qdio: pointer to structure zfcp_qdio
401 void zfcp_qdio_close(struct zfcp_qdio *qdio)
403 struct zfcp_qdio_queue *req_q;
406 if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
409 /* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */
410 req_q = &qdio->req_q;
411 spin_lock_bh(&qdio->req_q_lock);
412 atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status);
413 spin_unlock_bh(&qdio->req_q_lock);
415 qdio_shutdown(qdio->adapter->ccw_device,
416 QDIO_FLAG_CLEANUP_USING_CLEAR);
418 /* cleanup used outbound sbals */
419 count = atomic_read(&req_q->count);
420 if (count < QDIO_MAX_BUFFERS_PER_Q) {
421 first = (req_q->first + count) % QDIO_MAX_BUFFERS_PER_Q;
422 count = QDIO_MAX_BUFFERS_PER_Q - count;
423 zfcp_qdio_zero_sbals(req_q->sbal, first, count);
426 atomic_set(&req_q->count, 0);
427 qdio->resp_q.first = 0;
428 atomic_set(&qdio->resp_q.count, 0);
432 * zfcp_qdio_open - prepare and initialize response queue
433 * @qdio: pointer to struct zfcp_qdio
434 * Returns: 0 on success, otherwise -EIO
436 int zfcp_qdio_open(struct zfcp_qdio *qdio)
438 struct qdio_buffer_element *sbale;
439 struct qdio_initialize init_data;
440 struct ccw_device *cdev = qdio->adapter->ccw_device;
443 if (atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)
446 zfcp_qdio_setup_init_data(&init_data, qdio);
448 if (qdio_establish(&init_data))
449 goto failed_establish;
451 if (qdio_activate(cdev))
454 for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) {
455 sbale = &(qdio->resp_q.sbal[cc]->element[0]);
457 sbale->flags = SBAL_FLAGS_LAST_ENTRY;
461 if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0,
462 QDIO_MAX_BUFFERS_PER_Q))
465 /* set index of first avalable SBALS / number of available SBALS */
466 qdio->req_q.first = 0;
467 atomic_set(&qdio->req_q.count, QDIO_MAX_BUFFERS_PER_Q);
472 qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
475 "Setting up the QDIO connection to the FCP adapter failed\n");