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 
sas_init_dev(struct domain_device * dev)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  */
sas_get_port_device(struct asd_sas_port * port)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 
sas_notify_lldd_dev_found(struct domain_device * dev)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 
sas_notify_lldd_dev_gone(struct domain_device * dev)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  */
sas_discover_end_dev(struct domain_device * dev)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 
sas_unregister_common_dev(struct domain_device * dev)222 static inline void sas_unregister_common_dev(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 	list_del_init(&dev->dev_list_node);
230 }
231 
sas_unregister_dev(struct domain_device * dev)232 void sas_unregister_dev(struct domain_device *dev)
233 {
234 	if (dev->rphy) {
235 		sas_remove_children(&dev->rphy->dev);
236 		sas_rphy_delete(dev->rphy);
237 		dev->rphy = NULL;
238 	}
239 	if (dev->dev_type == EDGE_DEV || dev->dev_type == FANOUT_DEV) {
240 		/* remove the phys and ports, everything else should be gone */
241 		kfree(dev->ex_dev.ex_phy);
242 		dev->ex_dev.ex_phy = NULL;
243 	}
244 	sas_unregister_common_dev(dev);
245 }
246 
sas_unregister_domain_devices(struct asd_sas_port * port)247 void sas_unregister_domain_devices(struct asd_sas_port *port)
248 {
249 	struct domain_device *dev, *n;
250 
251 	list_for_each_entry_safe_reverse(dev,n,&port->dev_list,dev_list_node)
252 		sas_unregister_dev(dev);
253 
254 	port->port->rphy = NULL;
255 
256 }
257 
258 /* ---------- Discovery and Revalidation ---------- */
259 
260 /**
261  * sas_discover_domain -- discover the domain
262  * @port: port to the domain of interest
263  *
264  * NOTE: this process _must_ quit (return) as soon as any connection
265  * errors are encountered.  Connection recovery is done elsewhere.
266  * Discover process only interrogates devices in order to discover the
267  * domain.
268  */
sas_discover_domain(struct work_struct * work)269 static void sas_discover_domain(struct work_struct *work)
270 {
271 	struct domain_device *dev;
272 	int error = 0;
273 	struct sas_discovery_event *ev =
274 		container_of(work, struct sas_discovery_event, work);
275 	struct asd_sas_port *port = ev->port;
276 
277 	sas_begin_event(DISCE_DISCOVER_DOMAIN, &port->disc.disc_event_lock,
278 			&port->disc.pending);
279 
280 	if (port->port_dev)
281 		return;
282 
283 	error = sas_get_port_device(port);
284 	if (error)
285 		return;
286 	dev = port->port_dev;
287 
288 	SAS_DPRINTK("DOING DISCOVERY on port %d, pid:%d\n", port->id,
289 		    task_pid_nr(current));
290 
291 	switch (dev->dev_type) {
292 	case SAS_END_DEV:
293 		error = sas_discover_end_dev(dev);
294 		break;
295 	case EDGE_DEV:
296 	case FANOUT_DEV:
297 		error = sas_discover_root_expander(dev);
298 		break;
299 	case SATA_DEV:
300 	case SATA_PM:
301 #ifdef CONFIG_SCSI_SAS_ATA
302 		error = sas_discover_sata(dev);
303 		break;
304 #else
305 		SAS_DPRINTK("ATA device seen but CONFIG_SCSI_SAS_ATA=N so cannot attach\n");
306 		/* Fall through */
307 #endif
308 	default:
309 		error = -ENXIO;
310 		SAS_DPRINTK("unhandled device %d\n", dev->dev_type);
311 		break;
312 	}
313 
314 	if (error) {
315 		sas_rphy_free(dev->rphy);
316 		dev->rphy = NULL;
317 
318 		spin_lock_irq(&port->dev_list_lock);
319 		list_del_init(&dev->dev_list_node);
320 		spin_unlock_irq(&port->dev_list_lock);
321 
322 		kfree(dev); /* not kobject_register-ed yet */
323 		port->port_dev = NULL;
324 	}
325 
326 	SAS_DPRINTK("DONE DISCOVERY on port %d, pid:%d, result:%d\n", port->id,
327 		    task_pid_nr(current), error);
328 }
329 
sas_revalidate_domain(struct work_struct * work)330 static void sas_revalidate_domain(struct work_struct *work)
331 {
332 	int res = 0;
333 	struct sas_discovery_event *ev =
334 		container_of(work, struct sas_discovery_event, work);
335 	struct asd_sas_port *port = ev->port;
336 
337 	sas_begin_event(DISCE_REVALIDATE_DOMAIN, &port->disc.disc_event_lock,
338 			&port->disc.pending);
339 
340 	SAS_DPRINTK("REVALIDATING DOMAIN on port %d, pid:%d\n", port->id,
341 		    task_pid_nr(current));
342 	if (port->port_dev)
343 		res = sas_ex_revalidate_domain(port->port_dev);
344 
345 	SAS_DPRINTK("done REVALIDATING DOMAIN on port %d, pid:%d, res 0x%x\n",
346 		    port->id, task_pid_nr(current), res);
347 }
348 
349 /* ---------- Events ---------- */
350 
sas_discover_event(struct asd_sas_port * port,enum discover_event ev)351 int sas_discover_event(struct asd_sas_port *port, enum discover_event ev)
352 {
353 	struct sas_discovery *disc;
354 
355 	if (!port)
356 		return 0;
357 	disc = &port->disc;
358 
359 	BUG_ON(ev >= DISC_NUM_EVENTS);
360 
361 	sas_queue_event(ev, &disc->disc_event_lock, &disc->pending,
362 			&disc->disc_work[ev].work, port->ha);
363 
364 	return 0;
365 }
366 
367 /**
368  * sas_init_disc -- initialize the discovery struct in the port
369  * @port: pointer to struct port
370  *
371  * Called when the ports are being initialized.
372  */
sas_init_disc(struct sas_discovery * disc,struct asd_sas_port * port)373 void sas_init_disc(struct sas_discovery *disc, struct asd_sas_port *port)
374 {
375 	int i;
376 
377 	static const work_func_t sas_event_fns[DISC_NUM_EVENTS] = {
378 		[DISCE_DISCOVER_DOMAIN] = sas_discover_domain,
379 		[DISCE_REVALIDATE_DOMAIN] = sas_revalidate_domain,
380 	};
381 
382 	spin_lock_init(&disc->disc_event_lock);
383 	disc->pending = 0;
384 	for (i = 0; i < DISC_NUM_EVENTS; i++) {
385 		INIT_WORK(&disc->disc_work[i].work, sas_event_fns[i]);
386 		disc->disc_work[i].port = port;
387 	}
388 }
389