s390: use free_netdev(netdev) instead of kfree()
[linux-2.6.git] / drivers / s390 / scsi / zfcp_qdio.c
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
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  */
305 static 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  */
322 void 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  */
355 int 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
401 failed_qdio:
402         qdio_shutdown(cdev, QDIO_FLAG_CLEANUP_USING_CLEAR);
403 failed_establish:
404         dev_err(&cdev->dev,
405                 "Setting up the QDIO connection to the FCP adapter failed\n");
406         return -EIO;
407 }
408
409 void 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
427 int 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  */
460 void 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 }