[SCSI] libsas: prevent domain rediscovery competing with ata error handling
[deliverable/linux.git] / drivers / scsi / libsas / sas_discover.c
1 /*
2 * Serial Attached SCSI (SAS) Discover process
3 *
4 * Copyright (C) 2005 Adaptec, Inc. All rights reserved.
5 * Copyright (C) 2005 Luben Tuikov <luben_tuikov@adaptec.com>
6 *
7 * This file is licensed under GPLv2.
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation; either version 2 of the
12 * License, or (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22 *
23 */
24
25 #include <linux/scatterlist.h>
26 #include <linux/slab.h>
27 #include <scsi/scsi_host.h>
28 #include <scsi/scsi_eh.h>
29 #include "sas_internal.h"
30
31 #include <scsi/scsi_transport.h>
32 #include <scsi/scsi_transport_sas.h>
33 #include <scsi/sas_ata.h>
34 #include "../scsi_sas_internal.h"
35
36 /* ---------- Basic task processing for discovery purposes ---------- */
37
38 void sas_init_dev(struct domain_device *dev)
39 {
40 switch (dev->dev_type) {
41 case SAS_END_DEV:
42 break;
43 case EDGE_DEV:
44 case FANOUT_DEV:
45 INIT_LIST_HEAD(&dev->ex_dev.children);
46 break;
47 case SATA_DEV:
48 case SATA_PM:
49 case SATA_PM_PORT:
50 INIT_LIST_HEAD(&dev->sata_dev.children);
51 break;
52 default:
53 break;
54 }
55 }
56
57 /* ---------- Domain device discovery ---------- */
58
59 /**
60 * sas_get_port_device -- Discover devices which caused port creation
61 * @port: pointer to struct sas_port of interest
62 *
63 * Devices directly attached to a HA port, have no parent. This is
64 * how we know they are (domain) "root" devices. All other devices
65 * do, and should have their "parent" pointer set appropriately as
66 * soon as a child device is discovered.
67 */
68 static int sas_get_port_device(struct asd_sas_port *port)
69 {
70 unsigned long flags;
71 struct asd_sas_phy *phy;
72 struct sas_rphy *rphy;
73 struct domain_device *dev;
74
75 dev = sas_alloc_device();
76 if (!dev)
77 return -ENOMEM;
78
79 spin_lock_irqsave(&port->phy_list_lock, flags);
80 if (list_empty(&port->phy_list)) {
81 spin_unlock_irqrestore(&port->phy_list_lock, flags);
82 sas_put_device(dev);
83 return -ENODEV;
84 }
85 phy = container_of(port->phy_list.next, struct asd_sas_phy, port_phy_el);
86 spin_lock(&phy->frame_rcvd_lock);
87 memcpy(dev->frame_rcvd, phy->frame_rcvd, min(sizeof(dev->frame_rcvd),
88 (size_t)phy->frame_rcvd_size));
89 spin_unlock(&phy->frame_rcvd_lock);
90 spin_unlock_irqrestore(&port->phy_list_lock, flags);
91
92 if (dev->frame_rcvd[0] == 0x34 && port->oob_mode == SATA_OOB_MODE) {
93 struct dev_to_host_fis *fis =
94 (struct dev_to_host_fis *) dev->frame_rcvd;
95 if (fis->interrupt_reason == 1 && fis->lbal == 1 &&
96 fis->byte_count_low==0x69 && fis->byte_count_high == 0x96
97 && (fis->device & ~0x10) == 0)
98 dev->dev_type = SATA_PM;
99 else
100 dev->dev_type = SATA_DEV;
101 dev->tproto = SAS_PROTOCOL_SATA;
102 } else {
103 struct sas_identify_frame *id =
104 (struct sas_identify_frame *) dev->frame_rcvd;
105 dev->dev_type = id->dev_type;
106 dev->iproto = id->initiator_bits;
107 dev->tproto = id->target_bits;
108 }
109
110 sas_init_dev(dev);
111
112 switch (dev->dev_type) {
113 case SAS_END_DEV:
114 case SATA_DEV:
115 rphy = sas_end_device_alloc(port->port);
116 break;
117 case EDGE_DEV:
118 rphy = sas_expander_alloc(port->port,
119 SAS_EDGE_EXPANDER_DEVICE);
120 break;
121 case FANOUT_DEV:
122 rphy = sas_expander_alloc(port->port,
123 SAS_FANOUT_EXPANDER_DEVICE);
124 break;
125 default:
126 printk("ERROR: Unidentified device type %d\n", dev->dev_type);
127 rphy = NULL;
128 break;
129 }
130
131 if (!rphy) {
132 sas_put_device(dev);
133 return -ENODEV;
134 }
135 rphy->identify.phy_identifier = phy->phy->identify.phy_identifier;
136 memcpy(dev->sas_addr, port->attached_sas_addr, SAS_ADDR_SIZE);
137 sas_fill_in_rphy(dev, rphy);
138 sas_hash_addr(dev->hashed_sas_addr, dev->sas_addr);
139 port->port_dev = dev;
140 dev->port = port;
141 dev->linkrate = port->linkrate;
142 dev->min_linkrate = port->linkrate;
143 dev->max_linkrate = port->linkrate;
144 dev->pathways = port->num_phys;
145 memset(port->disc.fanout_sas_addr, 0, SAS_ADDR_SIZE);
146 memset(port->disc.eeds_a, 0, SAS_ADDR_SIZE);
147 memset(port->disc.eeds_b, 0, SAS_ADDR_SIZE);
148 port->disc.max_level = 0;
149
150 dev->rphy = rphy;
151
152 if (dev_is_sata(dev))
153 list_add_tail(&dev->disco_list_node, &port->disco_list);
154 else {
155 spin_lock_irq(&port->dev_list_lock);
156 list_add_tail(&dev->dev_list_node, &port->dev_list);
157 spin_unlock_irq(&port->dev_list_lock);
158 }
159
160 return 0;
161 }
162
163 /* ---------- Discover and Revalidate ---------- */
164
165 int sas_notify_lldd_dev_found(struct domain_device *dev)
166 {
167 int res = 0;
168 struct sas_ha_struct *sas_ha = dev->port->ha;
169 struct Scsi_Host *shost = sas_ha->core.shost;
170 struct sas_internal *i = to_sas_internal(shost->transportt);
171
172 if (i->dft->lldd_dev_found) {
173 res = i->dft->lldd_dev_found(dev);
174 if (res) {
175 printk("sas: driver on pcidev %s cannot handle "
176 "device %llx, error:%d\n",
177 dev_name(sas_ha->dev),
178 SAS_ADDR(dev->sas_addr), res);
179 }
180 kref_get(&dev->kref);
181 }
182 return res;
183 }
184
185
186 void sas_notify_lldd_dev_gone(struct domain_device *dev)
187 {
188 struct sas_ha_struct *sas_ha = dev->port->ha;
189 struct Scsi_Host *shost = sas_ha->core.shost;
190 struct sas_internal *i = to_sas_internal(shost->transportt);
191
192 if (i->dft->lldd_dev_gone) {
193 i->dft->lldd_dev_gone(dev);
194 sas_put_device(dev);
195 }
196 }
197
198 /* ---------- Common/dispatchers ---------- */
199
200
201 /**
202 * sas_discover_end_dev -- discover an end device (SSP, etc)
203 * @end: pointer to domain device of interest
204 *
205 * See comment in sas_discover_sata().
206 */
207 int sas_discover_end_dev(struct domain_device *dev)
208 {
209 int res;
210
211 res = sas_notify_lldd_dev_found(dev);
212 if (res)
213 goto out_err2;
214
215 res = sas_rphy_add(dev->rphy);
216 if (res)
217 goto out_err;
218
219 return 0;
220
221 out_err:
222 sas_notify_lldd_dev_gone(dev);
223 out_err2:
224 return res;
225 }
226
227 /* ---------- Device registration and unregistration ---------- */
228
229 void sas_free_device(struct kref *kref)
230 {
231 struct domain_device *dev = container_of(kref, typeof(*dev), kref);
232
233 if (dev->parent)
234 sas_put_device(dev->parent);
235
236 /* remove the phys and ports, everything else should be gone */
237 if (dev->dev_type == EDGE_DEV || dev->dev_type == FANOUT_DEV)
238 kfree(dev->ex_dev.ex_phy);
239
240 if (dev_is_sata(dev)) {
241 kfree(dev->sata_dev.identify_device);
242 kfree(dev->sata_dev.identify_packet_device);
243 }
244
245 kfree(dev);
246 }
247
248 static void sas_unregister_common_dev(struct asd_sas_port *port, struct domain_device *dev)
249 {
250 sas_notify_lldd_dev_gone(dev);
251 if (!dev->parent)
252 dev->port->port_dev = NULL;
253 else
254 list_del_init(&dev->siblings);
255
256 spin_lock_irq(&port->dev_list_lock);
257 list_del_init(&dev->dev_list_node);
258 spin_unlock_irq(&port->dev_list_lock);
259
260 sas_put_device(dev);
261 }
262
263 static void sas_destruct_devices(struct work_struct *work)
264 {
265 struct domain_device *dev, *n;
266 struct sas_discovery_event *ev =
267 container_of(work, struct sas_discovery_event, work);
268 struct asd_sas_port *port = ev->port;
269
270 clear_bit(DISCE_DESTRUCT, &port->disc.pending);
271
272 list_for_each_entry_safe(dev, n, &port->destroy_list, disco_list_node) {
273 list_del_init(&dev->disco_list_node);
274
275 sas_remove_children(&dev->rphy->dev);
276 sas_rphy_delete(dev->rphy);
277 dev->rphy = NULL;
278 sas_unregister_common_dev(port, dev);
279
280 sas_put_device(dev);
281 }
282 }
283
284 void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *dev)
285 {
286 if (!test_bit(SAS_DEV_DESTROY, &dev->state) &&
287 !list_empty(&dev->disco_list_node)) {
288 /* this rphy never saw sas_rphy_add */
289 list_del_init(&dev->disco_list_node);
290 sas_rphy_free(dev->rphy);
291 dev->rphy = NULL;
292 sas_unregister_common_dev(port, dev);
293 }
294
295 if (dev->rphy && !test_and_set_bit(SAS_DEV_DESTROY, &dev->state)) {
296 sas_rphy_unlink(dev->rphy);
297 list_move_tail(&dev->disco_list_node, &port->destroy_list);
298 sas_discover_event(dev->port, DISCE_DESTRUCT);
299 }
300 }
301
302 void sas_unregister_domain_devices(struct asd_sas_port *port)
303 {
304 struct domain_device *dev, *n;
305
306 list_for_each_entry_safe_reverse(dev, n, &port->dev_list, dev_list_node)
307 sas_unregister_dev(port, dev);
308 list_for_each_entry_safe(dev, n, &port->disco_list, disco_list_node)
309 sas_unregister_dev(port, dev);
310
311 port->port->rphy = NULL;
312
313 }
314
315 /* ---------- Discovery and Revalidation ---------- */
316
317 /**
318 * sas_discover_domain -- discover the domain
319 * @port: port to the domain of interest
320 *
321 * NOTE: this process _must_ quit (return) as soon as any connection
322 * errors are encountered. Connection recovery is done elsewhere.
323 * Discover process only interrogates devices in order to discover the
324 * domain.
325 */
326 static void sas_discover_domain(struct work_struct *work)
327 {
328 struct domain_device *dev;
329 int error = 0;
330 struct sas_discovery_event *ev =
331 container_of(work, struct sas_discovery_event, work);
332 struct asd_sas_port *port = ev->port;
333
334 clear_bit(DISCE_DISCOVER_DOMAIN, &port->disc.pending);
335
336 if (port->port_dev)
337 return;
338
339 error = sas_get_port_device(port);
340 if (error)
341 return;
342 dev = port->port_dev;
343
344 SAS_DPRINTK("DOING DISCOVERY on port %d, pid:%d\n", port->id,
345 task_pid_nr(current));
346
347 switch (dev->dev_type) {
348 case SAS_END_DEV:
349 error = sas_discover_end_dev(dev);
350 break;
351 case EDGE_DEV:
352 case FANOUT_DEV:
353 error = sas_discover_root_expander(dev);
354 break;
355 case SATA_DEV:
356 case SATA_PM:
357 #ifdef CONFIG_SCSI_SAS_ATA
358 error = sas_discover_sata(dev);
359 break;
360 #else
361 SAS_DPRINTK("ATA device seen but CONFIG_SCSI_SAS_ATA=N so cannot attach\n");
362 /* Fall through */
363 #endif
364 default:
365 error = -ENXIO;
366 SAS_DPRINTK("unhandled device %d\n", dev->dev_type);
367 break;
368 }
369
370 if (error) {
371 sas_rphy_free(dev->rphy);
372 dev->rphy = NULL;
373
374 list_del_init(&dev->disco_list_node);
375 spin_lock_irq(&port->dev_list_lock);
376 list_del_init(&dev->dev_list_node);
377 spin_unlock_irq(&port->dev_list_lock);
378
379 sas_put_device(dev);
380 port->port_dev = NULL;
381 }
382
383 SAS_DPRINTK("DONE DISCOVERY on port %d, pid:%d, result:%d\n", port->id,
384 task_pid_nr(current), error);
385 }
386
387 static void sas_revalidate_domain(struct work_struct *work)
388 {
389 int res = 0;
390 struct sas_discovery_event *ev =
391 container_of(work, struct sas_discovery_event, work);
392 struct asd_sas_port *port = ev->port;
393 struct sas_ha_struct *ha = port->ha;
394
395 /* prevent revalidation from finding sata links in recovery */
396 mutex_lock(&ha->disco_mutex);
397 if (test_bit(SAS_HA_ATA_EH_ACTIVE, &ha->state)) {
398 SAS_DPRINTK("REVALIDATION DEFERRED on port %d, pid:%d\n",
399 port->id, task_pid_nr(current));
400 goto out;
401 }
402
403 clear_bit(DISCE_REVALIDATE_DOMAIN, &port->disc.pending);
404
405 SAS_DPRINTK("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id,
406 task_pid_nr(current));
407
408 if (port->port_dev)
409 res = sas_ex_revalidate_domain(port->port_dev);
410
411 SAS_DPRINTK("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n",
412 port->id, task_pid_nr(current), res);
413 out:
414 mutex_unlock(&ha->disco_mutex);
415 }
416
417 /* ---------- Events ---------- */
418
419 static void sas_chain_work(struct sas_ha_struct *ha, struct work_struct *work)
420 {
421 /* chained work is not subject to SA_HA_DRAINING or SAS_HA_REGISTERED */
422 scsi_queue_work(ha->core.shost, work);
423 }
424
425 static void sas_chain_event(int event, unsigned long *pending,
426 struct work_struct *work,
427 struct sas_ha_struct *ha)
428 {
429 if (!test_and_set_bit(event, pending)) {
430 unsigned long flags;
431
432 spin_lock_irqsave(&ha->state_lock, flags);
433 sas_chain_work(ha, work);
434 spin_unlock_irqrestore(&ha->state_lock, flags);
435 }
436 }
437
438 int sas_discover_event(struct asd_sas_port *port, enum discover_event ev)
439 {
440 struct sas_discovery *disc;
441
442 if (!port)
443 return 0;
444 disc = &port->disc;
445
446 BUG_ON(ev >= DISC_NUM_EVENTS);
447
448 sas_chain_event(ev, &disc->pending, &disc->disc_work[ev].work, port->ha);
449
450 return 0;
451 }
452
453 /**
454 * sas_init_disc -- initialize the discovery struct in the port
455 * @port: pointer to struct port
456 *
457 * Called when the ports are being initialized.
458 */
459 void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *port)
460 {
461 int i;
462
463 static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = {
464 [DISCE_DISCOVER_DOMAIN] = sas_discover_domain,
465 [DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain,
466 [DISCE_PROBE] = sas_probe_sata,
467 [DISCE_DESTRUCT] = sas_destruct_devices,
468 };
469
470 disc->pending = 0;
471 for (i = 0; i < DISC_NUM_EVENTS; i++) {
472 INIT_WORK(&disc->disc_work[i].work, sas_event_fns[i]);
473 disc->disc_work[i].port = port;
474 }
475 }
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