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
37void 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 */
69static 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
161int 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
181void 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 */
200int 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
214out_err:
215	sas_notify_lldd_dev_gone(dev);
216out_err2:
217	return res;
218}
219
220/* ---------- Device registration and unregistration ---------- */
221
222static 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
235void 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
250void 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 */
272static 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
333static 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
354int 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 */
376void 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