xref: /linux/drivers/scsi/libsas/sas_discover.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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_internal.h"
34 
35 /* ---------- Basic task processing for discovery purposes ---------- */
36 
37 void sas_init_dev(struct domain_device *dev)
38 {
39         INIT_LIST_HEAD(&dev->siblings);
40         INIT_LIST_HEAD(&dev->dev_list_node);
41         switch (dev->dev_type) {
42         case SAS_END_DEV:
43                 break;
44         case EDGE_DEV:
45         case FANOUT_DEV:
46                 INIT_LIST_HEAD(&dev->ex_dev.children);
47                 break;
48         case SATA_DEV:
49         case SATA_PM:
50         case SATA_PM_PORT:
51                 INIT_LIST_HEAD(&dev->sata_dev.children);
52                 break;
53         default:
54                 break;
55         }
56 }
57 
58 /* ---------- Domain device discovery ---------- */
59 
60 /**
61  * sas_get_port_device -- Discover devices which caused port creation
62  * @port: pointer to struct sas_port of interest
63  *
64  * Devices directly attached to a HA port, have no parent.  This is
65  * how we know they are (domain) "root" devices.  All other devices
66  * do, and should have their "parent" pointer set appropriately as
67  * soon as a child device is discovered.
68  */
69 static int sas_get_port_device(struct asd_sas_port *port)
70 {
71 	unsigned long flags;
72 	struct asd_sas_phy *phy;
73 	struct sas_rphy *rphy;
74 	struct domain_device *dev;
75 
76 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
77 	if (!dev)
78 		return -ENOMEM;
79 
80 	spin_lock_irqsave(&port->phy_list_lock, flags);
81 	if (list_empty(&port->phy_list)) {
82 		spin_unlock_irqrestore(&port->phy_list_lock, flags);
83 		kfree(dev);
84 		return -ENODEV;
85 	}
86 	phy = container_of(port->phy_list.next, struct asd_sas_phy, port_phy_el);
87 	spin_lock(&phy->frame_rcvd_lock);
88 	memcpy(dev->frame_rcvd, phy->frame_rcvd, min(sizeof(dev->frame_rcvd),
89 					     (size_t)phy->frame_rcvd_size));
90 	spin_unlock(&phy->frame_rcvd_lock);
91 	spin_unlock_irqrestore(&port->phy_list_lock, flags);
92 
93 	if (dev->frame_rcvd[0] == 0x34 && port->oob_mode == SATA_OOB_MODE) {
94 		struct dev_to_host_fis *fis =
95 			(struct dev_to_host_fis *) dev->frame_rcvd;
96 		if (fis->interrupt_reason == 1 && fis->lbal == 1 &&
97 		    fis->byte_count_low==0x69 && fis->byte_count_high == 0x96
98 		    && (fis->device & ~0x10) == 0)
99 			dev->dev_type = SATA_PM;
100 		else
101 			dev->dev_type = SATA_DEV;
102 		dev->tproto = SAS_PROTOCOL_SATA;
103 	} else {
104 		struct sas_identify_frame *id =
105 			(struct sas_identify_frame *) dev->frame_rcvd;
106 		dev->dev_type = id->dev_type;
107 		dev->iproto = id->initiator_bits;
108 		dev->tproto = id->target_bits;
109 	}
110 
111 	sas_init_dev(dev);
112 
113 	switch (dev->dev_type) {
114 	case SAS_END_DEV:
115 	case SATA_DEV:
116 		rphy = sas_end_device_alloc(port->port);
117 		break;
118 	case EDGE_DEV:
119 		rphy = sas_expander_alloc(port->port,
120 					  SAS_EDGE_EXPANDER_DEVICE);
121 		break;
122 	case FANOUT_DEV:
123 		rphy = sas_expander_alloc(port->port,
124 					  SAS_FANOUT_EXPANDER_DEVICE);
125 		break;
126 	default:
127 		printk("ERROR: Unidentified device type %d\n", dev->dev_type);
128 		rphy = NULL;
129 		break;
130 	}
131 
132 	if (!rphy) {
133 		kfree(dev);
134 		return -ENODEV;
135 	}
136 	rphy->identify.phy_identifier = phy->phy->identify.phy_identifier;
137 	memcpy(dev->sas_addr, port->attached_sas_addr, SAS_ADDR_SIZE);
138 	sas_fill_in_rphy(dev, rphy);
139 	sas_hash_addr(dev->hashed_sas_addr, dev->sas_addr);
140 	port->port_dev = dev;
141 	dev->port = port;
142 	dev->linkrate = port->linkrate;
143 	dev->min_linkrate = port->linkrate;
144 	dev->max_linkrate = port->linkrate;
145 	dev->pathways = port->num_phys;
146 	memset(port->disc.fanout_sas_addr, 0, SAS_ADDR_SIZE);
147 	memset(port->disc.eeds_a, 0, SAS_ADDR_SIZE);
148 	memset(port->disc.eeds_b, 0, SAS_ADDR_SIZE);
149 	port->disc.max_level = 0;
150 
151 	dev->rphy = rphy;
152 	spin_lock_irq(&port->dev_list_lock);
153 	list_add_tail(&dev->dev_list_node, &port->dev_list);
154 	spin_unlock_irq(&port->dev_list_lock);
155 
156 	return 0;
157 }
158 
159 /* ---------- Discover and Revalidate ---------- */
160 
161 int sas_notify_lldd_dev_found(struct domain_device *dev)
162 {
163 	int res = 0;
164 	struct sas_ha_struct *sas_ha = dev->port->ha;
165 	struct Scsi_Host *shost = sas_ha->core.shost;
166 	struct sas_internal *i = to_sas_internal(shost->transportt);
167 
168 	if (i->dft->lldd_dev_found) {
169 		res = i->dft->lldd_dev_found(dev);
170 		if (res) {
171 			printk("sas: driver on pcidev %s cannot handle "
172 			       "device %llx, error:%d\n",
173 			       dev_name(sas_ha->dev),
174 			       SAS_ADDR(dev->sas_addr), res);
175 		}
176 	}
177 	return res;
178 }
179 
180 
181 void sas_notify_lldd_dev_gone(struct domain_device *dev)
182 {
183 	struct sas_ha_struct *sas_ha = dev->port->ha;
184 	struct Scsi_Host *shost = sas_ha->core.shost;
185 	struct sas_internal *i = to_sas_internal(shost->transportt);
186 
187 	if (i->dft->lldd_dev_gone)
188 		i->dft->lldd_dev_gone(dev);
189 }
190 
191 /* ---------- Common/dispatchers ---------- */
192 
193 
194 /**
195  * sas_discover_end_dev -- discover an end device (SSP, etc)
196  * @end: pointer to domain device of interest
197  *
198  * See comment in sas_discover_sata().
199  */
200 int sas_discover_end_dev(struct domain_device *dev)
201 {
202 	int res;
203 
204 	res = sas_notify_lldd_dev_found(dev);
205 	if (res)
206 		goto out_err2;
207 
208 	res = sas_rphy_add(dev->rphy);
209 	if (res)
210 		goto out_err;
211 
212 	return 0;
213 
214 out_err:
215 	sas_notify_lldd_dev_gone(dev);
216 out_err2:
217 	return res;
218 }
219 
220 /* ---------- Device registration and unregistration ---------- */
221 
222 static void sas_unregister_common_dev(struct asd_sas_port *port, struct domain_device *dev)
223 {
224 	sas_notify_lldd_dev_gone(dev);
225 	if (!dev->parent)
226 		dev->port->port_dev = NULL;
227 	else
228 		list_del_init(&dev->siblings);
229 
230 	spin_lock_irq(&port->dev_list_lock);
231 	list_del_init(&dev->dev_list_node);
232 	spin_unlock_irq(&port->dev_list_lock);
233 }
234 
235 void sas_unregister_dev(struct asd_sas_port *port, struct domain_device *dev)
236 {
237 	if (dev->rphy) {
238 		sas_remove_children(&dev->rphy->dev);
239 		sas_rphy_delete(dev->rphy);
240 		dev->rphy = NULL;
241 	}
242 	if (dev->dev_type == EDGE_DEV || dev->dev_type == FANOUT_DEV) {
243 		/* remove the phys and ports, everything else should be gone */
244 		kfree(dev->ex_dev.ex_phy);
245 		dev->ex_dev.ex_phy = NULL;
246 	}
247 	sas_unregister_common_dev(port, dev);
248 }
249 
250 void sas_unregister_domain_devices(struct asd_sas_port *port)
251 {
252 	struct domain_device *dev, *n;
253 
254 	list_for_each_entry_safe_reverse(dev, n, &port->dev_list, dev_list_node)
255 		sas_unregister_dev(port, dev);
256 
257 	port->port->rphy = NULL;
258 
259 }
260 
261 /* ---------- Discovery and Revalidation ---------- */
262 
263 /**
264  * sas_discover_domain -- discover the domain
265  * @port: port to the domain of interest
266  *
267  * NOTE: this process _must_ quit (return) as soon as any connection
268  * errors are encountered.  Connection recovery is done elsewhere.
269  * Discover process only interrogates devices in order to discover the
270  * domain.
271  */
272 static void sas_discover_domain(struct work_struct *work)
273 {
274 	struct domain_device *dev;
275 	int error = 0;
276 	struct sas_discovery_event *ev =
277 		container_of(work, struct sas_discovery_event, work);
278 	struct asd_sas_port *port = ev->port;
279 
280 	sas_begin_event(DISCE_DISCOVER_DOMAIN, &port->disc.disc_event_lock,
281 			&port->disc.pending);
282 
283 	if (port->port_dev)
284 		return;
285 
286 	error = sas_get_port_device(port);
287 	if (error)
288 		return;
289 	dev = port->port_dev;
290 
291 	SAS_DPRINTK("DOING DISCOVERY on port %d, pid:%d\n", port->id,
292 		    task_pid_nr(current));
293 
294 	switch (dev->dev_type) {
295 	case SAS_END_DEV:
296 		error = sas_discover_end_dev(dev);
297 		break;
298 	case EDGE_DEV:
299 	case FANOUT_DEV:
300 		error = sas_discover_root_expander(dev);
301 		break;
302 	case SATA_DEV:
303 	case SATA_PM:
304 #ifdef CONFIG_SCSI_SAS_ATA
305 		error = sas_discover_sata(dev);
306 		break;
307 #else
308 		SAS_DPRINTK("ATA device seen but CONFIG_SCSI_SAS_ATA=N so cannot attach\n");
309 		/* Fall through */
310 #endif
311 	default:
312 		error = -ENXIO;
313 		SAS_DPRINTK("unhandled device %d\n", dev->dev_type);
314 		break;
315 	}
316 
317 	if (error) {
318 		sas_rphy_free(dev->rphy);
319 		dev->rphy = NULL;
320 
321 		spin_lock_irq(&port->dev_list_lock);
322 		list_del_init(&dev->dev_list_node);
323 		spin_unlock_irq(&port->dev_list_lock);
324 
325 		kfree(dev); /* not kobject_register-ed yet */
326 		port->port_dev = NULL;
327 	}
328 
329 	SAS_DPRINTK("DONE DISCOVERY on port %d, pid:%d, result:%d\n", port->id,
330 		    task_pid_nr(current), error);
331 }
332 
333 static void sas_revalidate_domain(struct work_struct *work)
334 {
335 	int res = 0;
336 	struct sas_discovery_event *ev =
337 		container_of(work, struct sas_discovery_event, work);
338 	struct asd_sas_port *port = ev->port;
339 
340 	sas_begin_event(DISCE_REVALIDATE_DOMAIN, &port->disc.disc_event_lock,
341 			&port->disc.pending);
342 
343 	SAS_DPRINTK("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id,
344 		    task_pid_nr(current));
345 	if (port->port_dev)
346 		res = sas_ex_revalidate_domain(port->port_dev);
347 
348 	SAS_DPRINTK("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n",
349 		    port->id, task_pid_nr(current), res);
350 }
351 
352 /* ---------- Events ---------- */
353 
354 int sas_discover_event(struct asd_sas_port *port, enum discover_event ev)
355 {
356 	struct sas_discovery *disc;
357 
358 	if (!port)
359 		return 0;
360 	disc = &port->disc;
361 
362 	BUG_ON(ev >= DISC_NUM_EVENTS);
363 
364 	sas_queue_event(ev, &disc->disc_event_lock, &disc->pending,
365 			&disc->disc_work[ev].work, port->ha);
366 
367 	return 0;
368 }
369 
370 /**
371  * sas_init_disc -- initialize the discovery struct in the port
372  * @port: pointer to struct port
373  *
374  * Called when the ports are being initialized.
375  */
376 void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *port)
377 {
378 	int i;
379 
380 	static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = {
381 		[DISCE_DISCOVER_DOMAIN] = sas_discover_domain,
382 		[DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain,
383 	};
384 
385 	spin_lock_init(&disc->disc_event_lock);
386 	disc->pending = 0;
387 	for (i = 0; i < DISC_NUM_EVENTS; i++) {
388 		INIT_WORK(&disc->disc_work[i].work, sas_event_fns[i]);
389 		disc->disc_work[i].port = port;
390 	}
391 }
392