4 * Setup and helper functions to access QDIO.
6 * Copyright IBM Corporation 2002, 2010
9 #define KMSG_COMPONENT "zfcp"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12 #include <linux/slab.h>
14 #include "zfcp_qdio.h"
16 #define QBUFF_PER_PAGE (PAGE_SIZE / sizeof(struct qdio_buffer))
18 static int zfcp_qdio_buffers_enqueue(struct qdio_buffer **sbal)
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);
27 for (pos = 0; pos < QDIO_MAX_BUFFERS_PER_Q; pos++)
28 if (pos % QBUFF_PER_PAGE)
29 sbal[pos] = sbal[pos - 1] + 1;
33 static void zfcp_qdio_handler_error(struct zfcp_qdio *qdio, char *id)
35 struct zfcp_adapter *adapter = qdio->adapter;
37 dev_warn(&adapter->ccw_device->dev, "A QDIO problem occurred\n");
39 zfcp_erp_adapter_reopen(adapter,
40 ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED |
41 ZFCP_STATUS_COMMON_ERP_FAILED, id, NULL);
44 static void zfcp_qdio_zero_sbals(struct qdio_buffer *sbal[], int first, int cnt)
48 for (i = first; i < first + cnt; i++) {
49 sbal_idx = i % QDIO_MAX_BUFFERS_PER_Q;
50 memset(sbal[sbal_idx], 0, sizeof(struct qdio_buffer));
54 /* this needs to be called prior to updating the queue fill level */
55 static inline void zfcp_qdio_account(struct zfcp_qdio *qdio)
57 unsigned long long now, span;
60 spin_lock(&qdio->stat_lock);
61 now = get_clock_monotonic();
62 span = (now - qdio->req_q_time) >> 12;
63 free = atomic_read(&qdio->req_q.count);
64 used = QDIO_MAX_BUFFERS_PER_Q - free;
65 qdio->req_q_util += used * span;
66 qdio->req_q_time = now;
67 spin_unlock(&qdio->stat_lock);
70 static void zfcp_qdio_int_req(struct ccw_device *cdev, unsigned int qdio_err,
71 int queue_no, int first, int count,
74 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
75 struct zfcp_qdio_queue *queue = &qdio->req_q;
77 if (unlikely(qdio_err)) {
78 zfcp_dbf_hba_qdio(qdio->adapter->dbf, qdio_err, first,
80 zfcp_qdio_handler_error(qdio, "qdireq1");
84 /* cleanup all SBALs being program-owned now */
85 zfcp_qdio_zero_sbals(queue->sbal, first, count);
87 zfcp_qdio_account(qdio);
88 atomic_add(count, &queue->count);
89 wake_up(&qdio->req_q_wq);
92 static void zfcp_qdio_resp_put_back(struct zfcp_qdio *qdio, int processed)
94 struct zfcp_qdio_queue *queue = &qdio->resp_q;
95 struct ccw_device *cdev = qdio->adapter->ccw_device;
96 u8 count, start = queue->first;
99 count = atomic_read(&queue->count) + processed;
101 retval = do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, start, count);
103 if (unlikely(retval)) {
104 atomic_set(&queue->count, count);
105 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdrpb_1", NULL);
107 queue->first += count;
108 queue->first %= QDIO_MAX_BUFFERS_PER_Q;
109 atomic_set(&queue->count, 0);
113 static void zfcp_qdio_int_resp(struct ccw_device *cdev, unsigned int qdio_err,
114 int queue_no, int first, int count,
117 struct zfcp_qdio *qdio = (struct zfcp_qdio *) parm;
118 int sbal_idx, sbal_no;
120 if (unlikely(qdio_err)) {
121 zfcp_dbf_hba_qdio(qdio->adapter->dbf, qdio_err, first,
123 zfcp_qdio_handler_error(qdio, "qdires1");
128 * go through all SBALs from input queue currently
129 * returned by QDIO layer
131 for (sbal_no = 0; sbal_no < count; sbal_no++) {
132 sbal_idx = (first + sbal_no) % QDIO_MAX_BUFFERS_PER_Q;
133 /* go through all SBALEs of SBAL */
134 zfcp_fsf_reqid_check(qdio, sbal_idx);
138 * put range of SBALs back to response queue
139 * (including SBALs which have already been free before)
141 zfcp_qdio_resp_put_back(qdio, count);
144 static void zfcp_qdio_sbal_limit(struct zfcp_qdio *qdio,
145 struct zfcp_qdio_req *q_req, int max_sbals)
147 int count = atomic_read(&qdio->req_q.count);
148 count = min(count, max_sbals);
149 q_req->sbal_limit = (q_req->sbal_first + count - 1)
150 % QDIO_MAX_BUFFERS_PER_Q;
153 static struct qdio_buffer_element *
154 zfcp_qdio_sbal_chain(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
156 struct qdio_buffer_element *sbale;
158 /* set last entry flag in current SBALE of current SBAL */
159 sbale = zfcp_qdio_sbale_curr(qdio, q_req);
160 sbale->flags |= SBAL_FLAGS_LAST_ENTRY;
162 /* don't exceed last allowed SBAL */
163 if (q_req->sbal_last == q_req->sbal_limit)
166 /* set chaining flag in first SBALE of current SBAL */
167 sbale = zfcp_qdio_sbale_req(qdio, q_req);
168 sbale->flags |= SBAL_FLAGS0_MORE_SBALS;
170 /* calculate index of next SBAL */
172 q_req->sbal_last %= QDIO_MAX_BUFFERS_PER_Q;
174 /* keep this requests number of SBALs up-to-date */
175 q_req->sbal_number++;
177 /* start at first SBALE of new SBAL */
178 q_req->sbale_curr = 0;
180 /* set storage-block type for new SBAL */
181 sbale = zfcp_qdio_sbale_curr(qdio, q_req);
182 sbale->flags |= q_req->sbtype;
187 static struct qdio_buffer_element *
188 zfcp_qdio_sbale_next(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
190 if (q_req->sbale_curr == ZFCP_QDIO_LAST_SBALE_PER_SBAL)
191 return zfcp_qdio_sbal_chain(qdio, q_req);
193 return zfcp_qdio_sbale_curr(qdio, q_req);
196 static void zfcp_qdio_undo_sbals(struct zfcp_qdio *qdio,
197 struct zfcp_qdio_req *q_req)
199 struct qdio_buffer **sbal = qdio->req_q.sbal;
200 int first = q_req->sbal_first;
201 int last = q_req->sbal_last;
202 int count = (last - first + QDIO_MAX_BUFFERS_PER_Q) %
203 QDIO_MAX_BUFFERS_PER_Q + 1;
204 zfcp_qdio_zero_sbals(sbal, first, count);
208 * zfcp_qdio_sbals_from_sg - fill SBALs from scatter-gather list
209 * @qdio: pointer to struct zfcp_qdio
210 * @q_req: pointer to struct zfcp_qdio_req
211 * @sg: scatter-gather list
212 * @max_sbals: upper bound for number of SBALs to be used
213 * Returns: number of bytes, or error (negativ)
215 int zfcp_qdio_sbals_from_sg(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req,
216 struct scatterlist *sg, int max_sbals)
218 struct qdio_buffer_element *sbale;
221 /* figure out last allowed SBAL */
222 zfcp_qdio_sbal_limit(qdio, q_req, max_sbals);
224 /* set storage-block type for this request */
225 sbale = zfcp_qdio_sbale_req(qdio, q_req);
226 sbale->flags |= q_req->sbtype;
228 for (; sg; sg = sg_next(sg)) {
229 sbale = zfcp_qdio_sbale_next(qdio, q_req);
231 atomic_inc(&qdio->req_q_full);
232 zfcp_qdio_undo_sbals(qdio, q_req);
236 sbale->addr = sg_virt(sg);
237 sbale->length = sg->length;
242 /* assume that no other SBALEs are to follow in the same SBAL */
243 sbale = zfcp_qdio_sbale_curr(qdio, q_req);
244 sbale->flags |= SBAL_FLAGS_LAST_ENTRY;
249 static int zfcp_qdio_sbal_check(struct zfcp_qdio *qdio)
251 struct zfcp_qdio_queue *req_q = &qdio->req_q;
253 spin_lock_bh(&qdio->req_q_lock);
254 if (atomic_read(&req_q->count) ||
255 !(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
257 spin_unlock_bh(&qdio->req_q_lock);
262 * zfcp_qdio_sbal_get - get free sbal in request queue, wait if necessary
263 * @qdio: pointer to struct zfcp_qdio
265 * The req_q_lock must be held by the caller of this function, and
266 * this function may only be called from process context; it will
267 * sleep when waiting for a free sbal.
269 * Returns: 0 on success, -EIO if there is no free sbal after waiting.
271 int zfcp_qdio_sbal_get(struct zfcp_qdio *qdio)
275 spin_unlock_bh(&qdio->req_q_lock);
276 ret = wait_event_interruptible_timeout(qdio->req_q_wq,
277 zfcp_qdio_sbal_check(qdio), 5 * HZ);
279 if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
286 atomic_inc(&qdio->req_q_full);
287 /* assume hanging outbound queue, try queue recovery */
288 zfcp_erp_adapter_reopen(qdio->adapter, 0, "qdsbg_1", NULL);
291 spin_lock_bh(&qdio->req_q_lock);
296 * zfcp_qdio_send - set PCI flag in first SBALE and send req to QDIO
297 * @qdio: pointer to struct zfcp_qdio
298 * @q_req: pointer to struct zfcp_qdio_req
299 * Returns: 0 on success, error otherwise
301 int zfcp_qdio_send(struct zfcp_qdio *qdio, struct zfcp_qdio_req *q_req)
303 struct zfcp_qdio_queue *req_q = &qdio->req_q;
304 int first = q_req->sbal_first;
305 int count = q_req->sbal_number;
307 unsigned int qdio_flags = QDIO_FLAG_SYNC_OUTPUT;
309 zfcp_qdio_account(qdio);
311 retval = do_QDIO(qdio->adapter->ccw_device, qdio_flags, 0, first,
313 if (unlikely(retval)) {
314 zfcp_qdio_zero_sbals(req_q->sbal, first, count);
318 /* account for transferred buffers */
319 atomic_sub(count, &req_q->count);
320 req_q->first += count;
321 req_q->first %= QDIO_MAX_BUFFERS_PER_Q;
326 static void zfcp_qdio_setup_init_data(struct qdio_initialize *id,
327 struct zfcp_qdio *qdio)
330 id->cdev = qdio->adapter->ccw_device;
331 id->q_format = QDIO_ZFCP_QFMT;
332 memcpy(id->adapter_name, dev_name(&id->cdev->dev), 8);
333 ASCEBC(id->adapter_name, 8);
334 id->qib_param_field_format = 0;
335 id->qib_param_field = NULL;
336 id->input_slib_elements = NULL;
337 id->output_slib_elements = NULL;
339 id->no_output_qs = 1;
340 id->input_handler = zfcp_qdio_int_resp;
341 id->output_handler = zfcp_qdio_int_req;
342 id->int_parm = (unsigned long) qdio;
343 id->input_sbal_addr_array = (void **) (qdio->resp_q.sbal);
344 id->output_sbal_addr_array = (void **) (qdio->req_q.sbal);
348 * zfcp_qdio_allocate - allocate queue memory and initialize QDIO data
349 * @adapter: pointer to struct zfcp_adapter
350 * Returns: -ENOMEM on memory allocation error or return value from
353 static int zfcp_qdio_allocate(struct zfcp_qdio *qdio)
355 struct qdio_initialize init_data;
357 if (zfcp_qdio_buffers_enqueue(qdio->req_q.sbal) ||
358 zfcp_qdio_buffers_enqueue(qdio->resp_q.sbal))
361 zfcp_qdio_setup_init_data(&init_data, qdio);
363 return qdio_allocate(&init_data);
367 * zfcp_close_qdio - close qdio queues for an adapter
368 * @qdio: pointer to structure zfcp_qdio
370 void zfcp_qdio_close(struct zfcp_qdio *qdio)
372 struct zfcp_qdio_queue *req_q;
375 if (!(atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP))
378 /* clear QDIOUP flag, thus do_QDIO is not called during qdio_shutdown */
379 req_q = &qdio->req_q;
380 spin_lock_bh(&qdio->req_q_lock);
381 atomic_clear_mask(ZFCP_STATUS_ADAPTER_QDIOUP, &qdio->adapter->status);
382 spin_unlock_bh(&qdio->req_q_lock);
384 wake_up(&qdio->req_q_wq);
386 qdio_shutdown(qdio->adapter->ccw_device,
387 QDIO_FLAG_CLEANUP_USING_CLEAR);
389 /* cleanup used outbound sbals */
390 count = atomic_read(&req_q->count);
391 if (count < QDIO_MAX_BUFFERS_PER_Q) {
392 first = (req_q->first + count) % QDIO_MAX_BUFFERS_PER_Q;
393 count = QDIO_MAX_BUFFERS_PER_Q - count;
394 zfcp_qdio_zero_sbals(req_q->sbal, first, count);
397 atomic_set(&req_q->count, 0);
398 qdio->resp_q.first = 0;
399 atomic_set(&qdio->resp_q.count, 0);
403 * zfcp_qdio_open - prepare and initialize response queue
404 * @qdio: pointer to struct zfcp_qdio
405 * Returns: 0 on success, otherwise -EIO
407 int zfcp_qdio_open(struct zfcp_qdio *qdio)
409 struct qdio_buffer_element *sbale;
410 struct qdio_initialize init_data;
411 struct ccw_device *cdev = qdio->adapter->ccw_device;
414 if (atomic_read(&qdio->adapter->status) & ZFCP_STATUS_ADAPTER_QDIOUP)
417 zfcp_qdio_setup_init_data(&init_data, qdio);
419 if (qdio_establish(&init_data))
420 goto failed_establish;
422 if (qdio_activate(cdev))
425 for (cc = 0; cc < QDIO_MAX_BUFFERS_PER_Q; cc++) {
426 sbale = &(qdio->resp_q.sbal[cc]->element[0]);
428 sbale->flags = SBAL_FLAGS_LAST_ENTRY;
432 if (do_QDIO(cdev, QDIO_FLAG_SYNC_INPUT, 0, 0,
433 QDIO_MAX_BUFFERS_PER_Q))
436 /* set index of first avalable SBALS / number of available SBALS */
437 qdio->req_q.first = 0;
438 atomic_set(&qdio->req_q.count, QDIO_MAX_BUFFERS_PER_Q);
443 qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
446 "Setting up the QDIO connection to the FCP adapter failed\n");
450 void zfcp_qdio_destroy(struct zfcp_qdio *qdio)
452 struct qdio_buffer **sbal_req, **sbal_resp;
458 if (qdio->adapter->ccw_device)
459 qdio_free(qdio->adapter->ccw_device);
461 sbal_req = qdio->req_q.sbal;
462 sbal_resp = qdio->resp_q.sbal;
464 for (p = 0; p < QDIO_MAX_BUFFERS_PER_Q; p += QBUFF_PER_PAGE) {
465 free_page((unsigned long) sbal_req[p]);
466 free_page((unsigned long) sbal_resp[p]);
472 int zfcp_qdio_setup(struct zfcp_adapter *adapter)
474 struct zfcp_qdio *qdio;
476 qdio = kzalloc(sizeof(struct zfcp_qdio), GFP_KERNEL);
480 qdio->adapter = adapter;
482 if (zfcp_qdio_allocate(qdio)) {
483 zfcp_qdio_destroy(qdio);
487 spin_lock_init(&qdio->req_q_lock);
488 spin_lock_init(&qdio->stat_lock);
490 adapter->qdio = qdio;