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 <scsi/scsi_host.h>
27 #include <scsi/scsi_eh.h>
28 #include "sas_internal.h"
29 
30 #include <scsi/scsi_transport.h>
31 #include <scsi/scsi_transport_sas.h>
32 #include "../scsi_sas_internal.h"
33 
34 /* ---------- Basic task processing for discovery purposes ---------- */
35 
36 void sas_init_dev(struct domain_device *dev)
37 {
38         INIT_LIST_HEAD(&dev->siblings);
39         INIT_LIST_HEAD(&dev->dev_list_node);
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 = kzalloc(sizeof(*dev), GFP_KERNEL);
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 		kfree(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 		kfree(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 	spin_lock_irq(&port->dev_list_lock);
152 	list_add_tail(&dev->dev_list_node, &port->dev_list);
153 	spin_unlock_irq(&port->dev_list_lock);
154 
155 	return 0;
156 }
157 
158 /* ---------- Discover and Revalidate ---------- */
159 
160 int sas_notify_lldd_dev_found(struct domain_device *dev)
161 {
162 	int res = 0;
163 	struct sas_ha_struct *sas_ha = dev->port->ha;
164 	struct Scsi_Host *shost = sas_ha->core.shost;
165 	struct sas_internal *i = to_sas_internal(shost->transportt);
166 
167 	if (i->dft->lldd_dev_found) {
168 		res = i->dft->lldd_dev_found(dev);
169 		if (res) {
170 			printk("sas: driver on pcidev %s cannot handle "
171 			       "device %llx, error:%d\n",
172 			       sas_ha->dev->bus_id,
173 			       SAS_ADDR(dev->sas_addr), res);
174 		}
175 	}
176 	return res;
177 }
178 
179 
180 void sas_notify_lldd_dev_gone(struct domain_device *dev)
181 {
182 	struct sas_ha_struct *sas_ha = dev->port->ha;
183 	struct Scsi_Host *shost = sas_ha->core.shost;
184 	struct sas_internal *i = to_sas_internal(shost->transportt);
185 
186 	if (i->dft->lldd_dev_gone)
187 		i->dft->lldd_dev_gone(dev);
188 }
189 
190 /* ---------- Common/dispatchers ---------- */
191 
192 
193 /**
194  * sas_discover_end_dev -- discover an end device (SSP, etc)
195  * @end: pointer to domain device of interest
196  *
197  * See comment in sas_discover_sata().
198  */
199 int sas_discover_end_dev(struct domain_device *dev)
200 {
201 	int res;
202 
203 	res = sas_notify_lldd_dev_found(dev);
204 	if (res)
205 		goto out_err2;
206 
207 	res = sas_rphy_add(dev->rphy);
208 	if (res)
209 		goto out_err;
210 
211 	return 0;
212 
213 out_err:
214 	sas_notify_lldd_dev_gone(dev);
215 out_err2:
216 	return res;
217 }
218 
219 /* ---------- Device registration and unregistration ---------- */
220 
221 static inline void sas_unregister_common_dev(struct domain_device *dev)
222 {
223 	sas_notify_lldd_dev_gone(dev);
224 	if (!dev->parent)
225 		dev->port->port_dev = NULL;
226 	else
227 		list_del_init(&dev->siblings);
228 	list_del_init(&dev->dev_list_node);
229 }
230 
231 void sas_unregister_dev(struct domain_device *dev)
232 {
233 	if (dev->rphy) {
234 		sas_remove_children(&dev->rphy->dev);
235 		sas_rphy_delete(dev->rphy);
236 		dev->rphy = NULL;
237 	}
238 	if (dev->dev_type == EDGE_DEV || dev->dev_type == FANOUT_DEV) {
239 		/* remove the phys and ports, everything else should be gone */
240 		kfree(dev->ex_dev.ex_phy);
241 		dev->ex_dev.ex_phy = NULL;
242 	}
243 	sas_unregister_common_dev(dev);
244 }
245 
246 void sas_unregister_domain_devices(struct asd_sas_port *port)
247 {
248 	struct domain_device *dev, *n;
249 
250 	list_for_each_entry_safe_reverse(dev,n,&port->dev_list,dev_list_node)
251 		sas_unregister_dev(dev);
252 
253 	port->port->rphy = NULL;
254 
255 }
256 
257 /* ---------- Discovery and Revalidation ---------- */
258 
259 /**
260  * sas_discover_domain -- discover the domain
261  * @port: port to the domain of interest
262  *
263  * NOTE: this process _must_ quit (return) as soon as any connection
264  * errors are encountered.  Connection recovery is done elsewhere.
265  * Discover process only interrogates devices in order to discover the
266  * domain.
267  */
268 static void sas_discover_domain(struct work_struct *work)
269 {
270 	struct domain_device *dev;
271 	int error = 0;
272 	struct sas_discovery_event *ev =
273 		container_of(work, struct sas_discovery_event, work);
274 	struct asd_sas_port *port = ev->port;
275 
276 	sas_begin_event(DISCE_DISCOVER_DOMAIN, &port->disc.disc_event_lock,
277 			&port->disc.pending);
278 
279 	if (port->port_dev)
280 		return;
281 
282 	error = sas_get_port_device(port);
283 	if (error)
284 		return;
285 	dev = port->port_dev;
286 
287 	SAS_DPRINTK("DOING DISCOVERY on port %d, pid:%d\n", port->id,
288 		    task_pid_nr(current));
289 
290 	switch (dev->dev_type) {
291 	case SAS_END_DEV:
292 		error = sas_discover_end_dev(dev);
293 		break;
294 	case EDGE_DEV:
295 	case FANOUT_DEV:
296 		error = sas_discover_root_expander(dev);
297 		break;
298 	case SATA_DEV:
299 	case SATA_PM:
300 #ifdef CONFIG_SCSI_SAS_ATA
301 		error = sas_discover_sata(dev);
302 		break;
303 #else
304 		SAS_DPRINTK("ATA device seen but CONFIG_SCSI_SAS_ATA=N so cannot attach\n");
305 		/* Fall through */
306 #endif
307 	default:
308 		error = -ENXIO;
309 		SAS_DPRINTK("unhandled device %d\n", dev->dev_type);
310 		break;
311 	}
312 
313 	if (error) {
314 		sas_rphy_free(dev->rphy);
315 		dev->rphy = NULL;
316 
317 		spin_lock_irq(&port->dev_list_lock);
318 		list_del_init(&dev->dev_list_node);
319 		spin_unlock_irq(&port->dev_list_lock);
320 
321 		kfree(dev); /* not kobject_register-ed yet */
322 		port->port_dev = NULL;
323 	}
324 
325 	SAS_DPRINTK("DONE DISCOVERY on port %d, pid:%d, result:%d\n", port->id,
326 		    task_pid_nr(current), error);
327 }
328 
329 static void sas_revalidate_domain(struct work_struct *work)
330 {
331 	int res = 0;
332 	struct sas_discovery_event *ev =
333 		container_of(work, struct sas_discovery_event, work);
334 	struct asd_sas_port *port = ev->port;
335 
336 	sas_begin_event(DISCE_REVALIDATE_DOMAIN, &port->disc.disc_event_lock,
337 			&port->disc.pending);
338 
339 	SAS_DPRINTK("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id,
340 		    task_pid_nr(current));
341 	if (port->port_dev)
342 		res = sas_ex_revalidate_domain(port->port_dev);
343 
344 	SAS_DPRINTK("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n",
345 		    port->id, task_pid_nr(current), res);
346 }
347 
348 /* ---------- Events ---------- */
349 
350 int sas_discover_event(struct asd_sas_port *port, enum discover_event ev)
351 {
352 	struct sas_discovery *disc;
353 
354 	if (!port)
355 		return 0;
356 	disc = &port->disc;
357 
358 	BUG_ON(ev >= DISC_NUM_EVENTS);
359 
360 	sas_queue_event(ev, &disc->disc_event_lock, &disc->pending,
361 			&disc->disc_work[ev].work, port->ha);
362 
363 	return 0;
364 }
365 
366 /**
367  * sas_init_disc -- initialize the discovery struct in the port
368  * @port: pointer to struct port
369  *
370  * Called when the ports are being initialized.
371  */
372 void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *port)
373 {
374 	int i;
375 
376 	static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = {
377 		[DISCE_DISCOVER_DOMAIN] = sas_discover_domain,
378 		[DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain,
379 	};
380 
381 	spin_lock_init(&disc->disc_event_lock);
382 	disc->pending = 0;
383 	for (i = 0; i < DISC_NUM_EVENTS; i++) {
384 		INIT_WORK(&disc->disc_work[i].work, sas_event_fns[i]);
385 		disc->disc_work[i].port = port;
386 	}
387 }
388