xref: /linux/drivers/ata/libata-transport.c (revision 176000734ee2978121fde22a954eb1eabb204329)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Copyright 2008 ioogle, Inc.  All rights reserved.
4  *
5  * Libata transport class.
6  *
7  * The ATA transport class contains common code to deal with ATA HBAs,
8  * an approximated representation of ATA topologies in the driver model,
9  * and various sysfs attributes to expose these topologies and management
10  * interfaces to user-space.
11  *
12  * There are 3 objects defined in this class:
13  * - ata_port
14  * - ata_link
15  * - ata_device
16  * Each port has a link object. Each link can have up to two devices for PATA
17  * and generally one for SATA.
18  * If there is SATA port multiplier [PMP], 15 additional ata_link object are
19  * created.
20  *
21  * These objects are created when the ata host is initialized and when a PMP is
22  * found. They are removed only when the HBA is removed, cleaned before the
23  * error handler runs.
24  */
25 
26 
27 #include <linux/kernel.h>
28 #include <linux/blkdev.h>
29 #include <linux/spinlock.h>
30 #include <linux/slab.h>
31 #include <scsi/scsi_transport.h>
32 #include <linux/libata.h>
33 #include <linux/hdreg.h>
34 #include <linux/uaccess.h>
35 #include <linux/pm_runtime.h>
36 
37 #include "libata.h"
38 #include "libata-transport.h"
39 
40 #define ATA_PORT_ATTRS		3
41 #define ATA_LINK_ATTRS		3
42 #define ATA_DEV_ATTRS		9
43 
44 struct scsi_transport_template;
45 struct scsi_transport_template *ata_scsi_transport_template;
46 
47 struct ata_internal {
48 	struct scsi_transport_template t;
49 
50 	struct device_attribute private_port_attrs[ATA_PORT_ATTRS];
51 	struct device_attribute private_link_attrs[ATA_LINK_ATTRS];
52 	struct device_attribute private_dev_attrs[ATA_DEV_ATTRS];
53 
54 	struct transport_container link_attr_cont;
55 	struct transport_container dev_attr_cont;
56 
57 	/*
58 	 * The array of null terminated pointers to attributes
59 	 * needed by scsi_sysfs.c
60 	 */
61 	struct device_attribute *link_attrs[ATA_LINK_ATTRS + 1];
62 	struct device_attribute *port_attrs[ATA_PORT_ATTRS + 1];
63 	struct device_attribute *dev_attrs[ATA_DEV_ATTRS + 1];
64 };
65 #define to_ata_internal(tmpl)	container_of(tmpl, struct ata_internal, t)
66 
67 
68 #define tdev_to_device(d)					\
69 	container_of((d), struct ata_device, tdev)
70 #define transport_class_to_dev(dev)				\
71 	tdev_to_device((dev)->parent)
72 
73 #define tdev_to_link(d)						\
74 	container_of((d), struct ata_link, tdev)
75 #define transport_class_to_link(dev)				\
76 	tdev_to_link((dev)->parent)
77 
78 #define tdev_to_port(d)						\
79 	container_of((d), struct ata_port, tdev)
80 #define transport_class_to_port(dev)				\
81 	tdev_to_port((dev)->parent)
82 
83 /*
84  * Hack to allow attributes of the same name in different objects.
85  */
86 #define ATA_DEVICE_ATTR(_prefix,_name,_mode,_show,_store) \
87 	struct device_attribute device_attr_##_prefix##_##_name = \
88 	__ATTR(_name,_mode,_show,_store)
89 
90 #define ata_bitfield_name_match(title, table)			\
91 static ssize_t							\
92 get_ata_##title##_names(u32 table_key, char *buf)		\
93 {								\
94 	char *prefix = "";					\
95 	ssize_t len = 0;					\
96 	int i;							\
97 								\
98 	for (i = 0; i < ARRAY_SIZE(table); i++) {		\
99 		if (table[i].value & table_key) {		\
100 			len += sprintf(buf + len, "%s%s",	\
101 				prefix, table[i].name);		\
102 			prefix = ", ";				\
103 		}						\
104 	}							\
105 	len += sprintf(buf + len, "\n");			\
106 	return len;						\
107 }
108 
109 #define ata_bitfield_name_search(title, table)			\
110 static ssize_t							\
111 get_ata_##title##_names(u32 table_key, char *buf)		\
112 {								\
113 	ssize_t len = 0;					\
114 	int i;							\
115 								\
116 	for (i = 0; i < ARRAY_SIZE(table); i++) {		\
117 		if (table[i].value == table_key) {		\
118 			len += sprintf(buf + len, "%s",		\
119 				table[i].name);			\
120 			break;					\
121 		}						\
122 	}							\
123 	len += sprintf(buf + len, "\n");			\
124 	return len;						\
125 }
126 
127 static struct {
128 	u32		value;
129 	char		*name;
130 } ata_class_names[] = {
131 	{ ATA_DEV_UNKNOWN,		"unknown" },
132 	{ ATA_DEV_ATA,			"ata" },
133 	{ ATA_DEV_ATA_UNSUP,		"ata" },
134 	{ ATA_DEV_ATAPI,		"atapi" },
135 	{ ATA_DEV_ATAPI_UNSUP,		"atapi" },
136 	{ ATA_DEV_PMP,			"pmp" },
137 	{ ATA_DEV_PMP_UNSUP,		"pmp" },
138 	{ ATA_DEV_SEMB,			"semb" },
139 	{ ATA_DEV_SEMB_UNSUP,		"semb" },
140 	{ ATA_DEV_ZAC,			"zac" },
141 	{ ATA_DEV_NONE,			"none" }
142 };
143 ata_bitfield_name_search(class, ata_class_names)
144 
145 
146 static struct {
147 	u32		value;
148 	char		*name;
149 } ata_err_names[] = {
150 	{ AC_ERR_DEV,			"DeviceError" },
151 	{ AC_ERR_HSM,			"HostStateMachineError" },
152 	{ AC_ERR_TIMEOUT,		"Timeout" },
153 	{ AC_ERR_MEDIA,			"MediaError" },
154 	{ AC_ERR_ATA_BUS,		"BusError" },
155 	{ AC_ERR_HOST_BUS,		"HostBusError" },
156 	{ AC_ERR_SYSTEM,		"SystemError" },
157 	{ AC_ERR_INVALID,		"InvalidArg" },
158 	{ AC_ERR_OTHER,			"Unknown" },
159 	{ AC_ERR_NODEV_HINT,		"NoDeviceHint" },
160 	{ AC_ERR_NCQ,			"NCQError" }
161 };
162 ata_bitfield_name_match(err, ata_err_names)
163 
164 static struct {
165 	u32		value;
166 	char		*name;
167 } ata_xfer_names[] = {
168 	{ XFER_UDMA_7,			"XFER_UDMA_7" },
169 	{ XFER_UDMA_6,			"XFER_UDMA_6" },
170 	{ XFER_UDMA_5,			"XFER_UDMA_5" },
171 	{ XFER_UDMA_4,			"XFER_UDMA_4" },
172 	{ XFER_UDMA_3,			"XFER_UDMA_3" },
173 	{ XFER_UDMA_2,			"XFER_UDMA_2" },
174 	{ XFER_UDMA_1,			"XFER_UDMA_1" },
175 	{ XFER_UDMA_0,			"XFER_UDMA_0" },
176 	{ XFER_MW_DMA_4,		"XFER_MW_DMA_4" },
177 	{ XFER_MW_DMA_3,		"XFER_MW_DMA_3" },
178 	{ XFER_MW_DMA_2,		"XFER_MW_DMA_2" },
179 	{ XFER_MW_DMA_1,		"XFER_MW_DMA_1" },
180 	{ XFER_MW_DMA_0,		"XFER_MW_DMA_0" },
181 	{ XFER_SW_DMA_2,		"XFER_SW_DMA_2" },
182 	{ XFER_SW_DMA_1,		"XFER_SW_DMA_1" },
183 	{ XFER_SW_DMA_0,		"XFER_SW_DMA_0" },
184 	{ XFER_PIO_6,			"XFER_PIO_6" },
185 	{ XFER_PIO_5,			"XFER_PIO_5" },
186 	{ XFER_PIO_4,			"XFER_PIO_4" },
187 	{ XFER_PIO_3,			"XFER_PIO_3" },
188 	{ XFER_PIO_2,			"XFER_PIO_2" },
189 	{ XFER_PIO_1,			"XFER_PIO_1" },
190 	{ XFER_PIO_0,			"XFER_PIO_0" },
191 	{ XFER_PIO_SLOW,		"XFER_PIO_SLOW" }
192 };
193 ata_bitfield_name_search(xfer, ata_xfer_names)
194 
195 /*
196  * ATA Port attributes
197  */
198 #define ata_port_show_simple(field, name, format_string, cast)		\
199 static ssize_t								\
200 show_ata_port_##name(struct device *dev,				\
201 		     struct device_attribute *attr, char *buf)		\
202 {									\
203 	struct ata_port *ap = transport_class_to_port(dev);		\
204 									\
205 	return scnprintf(buf, 20, format_string, cast ap->field);	\
206 }
207 
208 #define ata_port_simple_attr(field, name, format_string, type)		\
209 	ata_port_show_simple(field, name, format_string, (type))	\
210 static DEVICE_ATTR(name, S_IRUGO, show_ata_port_##name, NULL)
211 
212 ata_port_simple_attr(nr_pmp_links, nr_pmp_links, "%d\n", int);
213 ata_port_simple_attr(stats.idle_irq, idle_irq, "%ld\n", unsigned long);
214 /* We want the port_no sysfs attibute to start at 1 (ap->port_no starts at 0) */
215 ata_port_simple_attr(port_no + 1, port_no, "%u\n", unsigned int);
216 
217 static DECLARE_TRANSPORT_CLASS(ata_port_class,
218 			       "ata_port", NULL, NULL, NULL);
219 
220 static void ata_tport_release(struct device *dev)
221 {
222 	struct ata_port *ap = tdev_to_port(dev);
223 	ata_host_put(ap->host);
224 }
225 
226 /**
227  * ata_is_port --  check if a struct device represents a ATA port
228  * @dev:	device to check
229  *
230  * Returns:
231  *	%1 if the device represents a ATA Port, %0 else
232  */
233 static int ata_is_port(const struct device *dev)
234 {
235 	return dev->release == ata_tport_release;
236 }
237 
238 static int ata_tport_match(struct attribute_container *cont,
239 			   struct device *dev)
240 {
241 	if (!ata_is_port(dev))
242 		return 0;
243 	return &ata_scsi_transport_template->host_attrs.ac == cont;
244 }
245 
246 /**
247  * ata_tport_delete  --  remove ATA PORT
248  * @ap:	ATA PORT to remove
249  *
250  * Removes the specified ATA PORT.  Remove the associated link as well.
251  */
252 void ata_tport_delete(struct ata_port *ap)
253 {
254 	struct device *dev = &ap->tdev;
255 
256 	ata_tlink_delete(&ap->link);
257 
258 	transport_remove_device(dev);
259 	device_del(dev);
260 	transport_destroy_device(dev);
261 	put_device(dev);
262 }
263 EXPORT_SYMBOL_GPL(ata_tport_delete);
264 
265 static const struct device_type ata_port_sas_type = {
266 	.name = ATA_PORT_TYPE_NAME,
267 };
268 
269 /** ata_tport_add - initialize a transport ATA port structure
270  *
271  * @parent:	parent device
272  * @ap:		existing ata_port structure
273  *
274  * Initialize a ATA port structure for sysfs.  It will be added to the device
275  * tree below the device specified by @parent which could be a PCI device.
276  *
277  * Returns %0 on success
278  */
279 int ata_tport_add(struct device *parent,
280 		  struct ata_port *ap)
281 {
282 	int error;
283 	struct device *dev = &ap->tdev;
284 
285 	device_initialize(dev);
286 	if (ap->flags & ATA_FLAG_SAS_HOST)
287 		dev->type = &ata_port_sas_type;
288 	else
289 		dev->type = &ata_port_type;
290 
291 	dev->parent = parent;
292 	ata_host_get(ap->host);
293 	dev->release = ata_tport_release;
294 	dev_set_name(dev, "ata%d", ap->print_id);
295 	transport_setup_device(dev);
296 	ata_acpi_bind_port(ap);
297 	error = device_add(dev);
298 	if (error) {
299 		goto tport_err;
300 	}
301 
302 	device_enable_async_suspend(dev);
303 	pm_runtime_set_active(dev);
304 	pm_runtime_enable(dev);
305 	pm_runtime_forbid(dev);
306 
307 	error = transport_add_device(dev);
308 	if (error)
309 		goto tport_transport_add_err;
310 	transport_configure_device(dev);
311 
312 	error = ata_tlink_add(&ap->link);
313 	if (error) {
314 		goto tport_link_err;
315 	}
316 	return 0;
317 
318  tport_link_err:
319 	transport_remove_device(dev);
320  tport_transport_add_err:
321 	device_del(dev);
322 
323  tport_err:
324 	transport_destroy_device(dev);
325 	put_device(dev);
326 	return error;
327 }
328 EXPORT_SYMBOL_GPL(ata_tport_add);
329 
330 /**
331  *     ata_port_classify - determine device type based on ATA-spec signature
332  *     @ap: ATA port device on which the classification should be run
333  *     @tf: ATA taskfile register set for device to be identified
334  *
335  *     A wrapper around ata_dev_classify() to provide additional logging
336  *
337  *     RETURNS:
338  *     Device type, %ATA_DEV_ATA, %ATA_DEV_ATAPI, %ATA_DEV_PMP,
339  *     %ATA_DEV_ZAC, or %ATA_DEV_UNKNOWN the event of failure.
340  */
341 unsigned int ata_port_classify(struct ata_port *ap,
342 			       const struct ata_taskfile *tf)
343 {
344 	int i;
345 	unsigned int class = ata_dev_classify(tf);
346 
347 	/* Start with index '1' to skip the 'unknown' entry */
348 	for (i = 1; i < ARRAY_SIZE(ata_class_names); i++) {
349 		if (ata_class_names[i].value == class) {
350 			ata_port_dbg(ap, "found %s device by sig\n",
351 				     ata_class_names[i].name);
352 			return class;
353 		}
354 	}
355 
356 	ata_port_info(ap, "found unknown device (class %u)\n", class);
357 	return class;
358 }
359 EXPORT_SYMBOL_GPL(ata_port_classify);
360 
361 /*
362  * ATA device attributes
363  */
364 
365 #define ata_dev_show_class(title, field)				\
366 static ssize_t								\
367 show_ata_dev_##field(struct device *dev,				\
368 		     struct device_attribute *attr, char *buf)		\
369 {									\
370 	struct ata_device *ata_dev = transport_class_to_dev(dev);	\
371 									\
372 	return get_ata_##title##_names(ata_dev->field, buf);		\
373 }
374 
375 #define ata_dev_attr(title, field)					\
376 	ata_dev_show_class(title, field)				\
377 static DEVICE_ATTR(field, S_IRUGO, show_ata_dev_##field, NULL)
378 
379 ata_dev_attr(class, class);
380 ata_dev_attr(xfer, pio_mode);
381 ata_dev_attr(xfer, dma_mode);
382 ata_dev_attr(xfer, xfer_mode);
383 
384 
385 #define ata_dev_show_simple(field, format_string, cast)			\
386 static ssize_t								\
387 show_ata_dev_##field(struct device *dev,				\
388 		     struct device_attribute *attr, char *buf)		\
389 {									\
390 	struct ata_device *ata_dev = transport_class_to_dev(dev);	\
391 									\
392 	return scnprintf(buf, 20, format_string, cast ata_dev->field);	\
393 }
394 
395 #define ata_dev_simple_attr(field, format_string, type)		\
396 	ata_dev_show_simple(field, format_string, (type))	\
397 	static DEVICE_ATTR(field, S_IRUGO,			\
398 		   show_ata_dev_##field, NULL)
399 
400 ata_dev_simple_attr(spdn_cnt, "%d\n", int);
401 
402 struct ata_show_ering_arg {
403 	char* buf;
404 	int written;
405 };
406 
407 static int ata_show_ering(struct ata_ering_entry *ent, void *void_arg)
408 {
409 	struct ata_show_ering_arg* arg = void_arg;
410 	u64 seconds;
411 	u32 rem;
412 
413 	seconds = div_u64_rem(ent->timestamp, HZ, &rem);
414 	arg->written += sprintf(arg->buf + arg->written,
415 				"[%5llu.%09lu]", seconds,
416 				rem * NSEC_PER_SEC / HZ);
417 	arg->written += get_ata_err_names(ent->err_mask,
418 					  arg->buf + arg->written);
419 	return 0;
420 }
421 
422 static ssize_t
423 show_ata_dev_ering(struct device *dev,
424 		   struct device_attribute *attr, char *buf)
425 {
426 	struct ata_device *ata_dev = transport_class_to_dev(dev);
427 	struct ata_show_ering_arg arg = { buf, 0 };
428 
429 	ata_ering_map(&ata_dev->ering, ata_show_ering, &arg);
430 	return arg.written;
431 }
432 
433 
434 static DEVICE_ATTR(ering, S_IRUGO, show_ata_dev_ering, NULL);
435 
436 static ssize_t
437 show_ata_dev_id(struct device *dev,
438 		struct device_attribute *attr, char *buf)
439 {
440 	struct ata_device *ata_dev = transport_class_to_dev(dev);
441 	int written = 0, i = 0;
442 
443 	if (ata_dev->class == ATA_DEV_PMP)
444 		return 0;
445 	for(i=0;i<ATA_ID_WORDS;i++)  {
446 		written += scnprintf(buf+written, 20, "%04x%c",
447 				    ata_dev->id[i],
448 				    ((i+1) & 7) ? ' ' : '\n');
449 	}
450 	return written;
451 }
452 
453 static DEVICE_ATTR(id, S_IRUGO, show_ata_dev_id, NULL);
454 
455 static ssize_t
456 show_ata_dev_gscr(struct device *dev,
457 		  struct device_attribute *attr, char *buf)
458 {
459 	struct ata_device *ata_dev = transport_class_to_dev(dev);
460 	int written = 0, i = 0;
461 
462 	if (ata_dev->class != ATA_DEV_PMP)
463 		return 0;
464 	for(i=0;i<SATA_PMP_GSCR_DWORDS;i++)  {
465 		written += scnprintf(buf+written, 20, "%08x%c",
466 				    ata_dev->gscr[i],
467 				    ((i+1) & 3) ? ' ' : '\n');
468 	}
469 	if (SATA_PMP_GSCR_DWORDS & 3)
470 		buf[written-1] = '\n';
471 	return written;
472 }
473 
474 static DEVICE_ATTR(gscr, S_IRUGO, show_ata_dev_gscr, NULL);
475 
476 static ssize_t
477 show_ata_dev_trim(struct device *dev,
478 		  struct device_attribute *attr, char *buf)
479 {
480 	struct ata_device *ata_dev = transport_class_to_dev(dev);
481 	unsigned char *mode;
482 
483 	if (!ata_id_has_trim(ata_dev->id))
484 		mode = "unsupported";
485 	else if (ata_dev->quirks & ATA_QUIRK_NOTRIM)
486 		mode = "forced_unsupported";
487 	else if (ata_dev->quirks & ATA_QUIRK_NO_NCQ_TRIM)
488 		mode = "forced_unqueued";
489 	else if (ata_fpdma_dsm_supported(ata_dev))
490 		mode = "queued";
491 	else
492 		mode = "unqueued";
493 
494 	return scnprintf(buf, 20, "%s\n", mode);
495 }
496 
497 static DEVICE_ATTR(trim, S_IRUGO, show_ata_dev_trim, NULL);
498 
499 static DECLARE_TRANSPORT_CLASS(ata_dev_class,
500 			       "ata_device", NULL, NULL, NULL);
501 
502 static void ata_tdev_release(struct device *dev)
503 {
504 }
505 
506 /**
507  * ata_is_ata_dev  --  check if a struct device represents a ATA device
508  * @dev:	device to check
509  *
510  * Returns:
511  *	true if the device represents a ATA device, false otherwise
512  */
513 static bool ata_is_ata_dev(const struct device *dev)
514 {
515 	return dev->release == ata_tdev_release;
516 }
517 
518 static int ata_tdev_match(struct attribute_container *cont,
519 			  struct device *dev)
520 {
521 	struct ata_internal *i = to_ata_internal(ata_scsi_transport_template);
522 
523 	if (!ata_is_ata_dev(dev))
524 		return 0;
525 	return &i->dev_attr_cont.ac == cont;
526 }
527 
528 /**
529  * ata_tdev_free  --  free an ATA transport device
530  * @dev:	struct ata_device owning the transport device to free
531  *
532  * Free the ATA transport device for the specified ATA device.
533  *
534  * Note:
535  *   This function must only be called for a ATA transport device that has not
536  *   yet successfully been added using ata_tdev_add().
537  */
538 static void ata_tdev_free(struct ata_device *dev)
539 {
540 	transport_destroy_device(&dev->tdev);
541 	put_device(&dev->tdev);
542 }
543 
544 /**
545  * ata_tdev_delete  --  remove an ATA transport device
546  * @ata_dev:	struct ata_device owning the transport device to delete
547  *
548  * Removes the ATA transport device for the specified ATA device.
549  */
550 static void ata_tdev_delete(struct ata_device *ata_dev)
551 {
552 	struct device *dev = &ata_dev->tdev;
553 
554 	transport_remove_device(dev);
555 	device_del(dev);
556 	ata_tdev_free(ata_dev);
557 }
558 
559 /**
560  * ata_tdev_add  --  initialize an ATA transport device
561  * @ata_dev:	struct ata_device owning the transport device to add
562  *
563  * Initialize an ATA transport device for sysfs.  It will be added in the
564  * device tree below the ATA link device it belongs to.
565  *
566  * Returns %0 on success and a negative error code on error.
567  */
568 static int ata_tdev_add(struct ata_device *ata_dev)
569 {
570 	struct device *dev = &ata_dev->tdev;
571 	struct ata_link *link = ata_dev->link;
572 	struct ata_port *ap = link->ap;
573 	int error;
574 
575 	device_initialize(dev);
576 	dev->parent = &link->tdev;
577 	dev->release = ata_tdev_release;
578 	if (ata_is_host_link(link))
579 		dev_set_name(dev, "dev%d.%d", ap->print_id,ata_dev->devno);
580 	else
581 		dev_set_name(dev, "dev%d.%d.0", ap->print_id, link->pmp);
582 
583 	transport_setup_device(dev);
584 	ata_acpi_bind_dev(ata_dev);
585 	error = device_add(dev);
586 	if (error) {
587 		ata_tdev_free(ata_dev);
588 		return error;
589 	}
590 
591 	error = transport_add_device(dev);
592 	if (error) {
593 		device_del(dev);
594 		ata_tdev_free(ata_dev);
595 		return error;
596 	}
597 
598 	transport_configure_device(dev);
599 	return 0;
600 }
601 
602 /*
603  * ATA link attributes
604  */
605 static int noop(int x)
606 {
607 	return x;
608 }
609 
610 #define ata_link_show_linkspeed(field, format)			\
611 static ssize_t							\
612 show_ata_link_##field(struct device *dev,			\
613 		      struct device_attribute *attr, char *buf)	\
614 {								\
615 	struct ata_link *link = transport_class_to_link(dev);	\
616 								\
617 	return sprintf(buf, "%s\n",				\
618 		       sata_spd_string(format(link->field)));	\
619 }
620 
621 #define ata_link_linkspeed_attr(field, format)			\
622 	ata_link_show_linkspeed(field, format)			\
623 static DEVICE_ATTR(field, 0444, show_ata_link_##field, NULL)
624 
625 ata_link_linkspeed_attr(hw_sata_spd_limit, fls);
626 ata_link_linkspeed_attr(sata_spd_limit, fls);
627 ata_link_linkspeed_attr(sata_spd, noop);
628 
629 static DECLARE_TRANSPORT_CLASS(ata_link_class,
630 		"ata_link", NULL, NULL, NULL);
631 
632 static void ata_tlink_release(struct device *dev)
633 {
634 }
635 
636 /**
637  * ata_is_link --  check if a struct device represents a ATA link
638  * @dev:	device to check
639  *
640  * Returns:
641  *	true if the device represents a ATA link, false otherwise
642  */
643 static bool ata_is_link(const struct device *dev)
644 {
645 	return dev->release == ata_tlink_release;
646 }
647 
648 static int ata_tlink_match(struct attribute_container *cont,
649 			    struct device *dev)
650 {
651 	struct ata_internal *i = to_ata_internal(ata_scsi_transport_template);
652 
653 	if (!ata_is_link(dev))
654 		return 0;
655 	return &i->link_attr_cont.ac == cont;
656 }
657 
658 /**
659  * ata_tlink_delete  --  remove an ATA link transport device
660  * @link:	struct ata_link owning the link transport device to remove
661  *
662  * Removes the link transport device of the specified ATA link. This also
663  * removes the ATA device(s) associated with the link as well.
664  */
665 void ata_tlink_delete(struct ata_link *link)
666 {
667 	struct device *dev = &link->tdev;
668 	struct ata_device *ata_dev;
669 
670 	ata_for_each_dev(ata_dev, link, ALL) {
671 		ata_tdev_delete(ata_dev);
672 	}
673 
674 	transport_remove_device(dev);
675 	device_del(dev);
676 	transport_destroy_device(dev);
677 	put_device(dev);
678 }
679 
680 /**
681  * ata_tlink_add  --  initialize an ATA link transport device
682  * @link:	struct ata_link owning the link transport device to initialize
683  *
684  * Initialize an ATA link transport device for sysfs. It will be added in the
685  * device tree below the ATA port it belongs to.
686  *
687  * Returns %0 on success and a negative error code on error.
688  */
689 int ata_tlink_add(struct ata_link *link)
690 {
691 	struct device *dev = &link->tdev;
692 	struct ata_port *ap = link->ap;
693 	struct ata_device *ata_dev;
694 	int error;
695 
696 	device_initialize(dev);
697 	dev->parent = &ap->tdev;
698 	dev->release = ata_tlink_release;
699 	if (ata_is_host_link(link))
700 		dev_set_name(dev, "link%d", ap->print_id);
701 	else
702 		dev_set_name(dev, "link%d.%d", ap->print_id, link->pmp);
703 
704 	transport_setup_device(dev);
705 
706 	error = device_add(dev);
707 	if (error)
708 		goto tlink_err;
709 
710 	error = transport_add_device(dev);
711 	if (error)
712 		goto tlink_transport_err;
713 	transport_configure_device(dev);
714 
715 	ata_for_each_dev(ata_dev, link, ALL) {
716 		error = ata_tdev_add(ata_dev);
717 		if (error)
718 			goto tlink_dev_err;
719 	}
720 	return 0;
721  tlink_dev_err:
722 	while (--ata_dev >= link->device)
723 		ata_tdev_delete(ata_dev);
724 	transport_remove_device(dev);
725  tlink_transport_err:
726 	device_del(dev);
727  tlink_err:
728 	transport_destroy_device(dev);
729 	put_device(dev);
730 	return error;
731 }
732 
733 /*
734  * Setup / Teardown code
735  */
736 
737 #define SETUP_TEMPLATE(attrb, field, perm, test)			\
738 	i->private_##attrb[count] = dev_attr_##field;			\
739 	i->private_##attrb[count].attr.mode = perm;			\
740 	i->attrb[count] = &i->private_##attrb[count];			\
741 	if (test)							\
742 		count++
743 
744 #define SETUP_LINK_ATTRIBUTE(field)					\
745 	SETUP_TEMPLATE(link_attrs, field, S_IRUGO, 1)
746 
747 #define SETUP_PORT_ATTRIBUTE(field)					\
748 	SETUP_TEMPLATE(port_attrs, field, S_IRUGO, 1)
749 
750 #define SETUP_DEV_ATTRIBUTE(field)					\
751 	SETUP_TEMPLATE(dev_attrs, field, S_IRUGO, 1)
752 
753 /**
754  * ata_attach_transport  --  instantiate ATA transport template
755  */
756 struct scsi_transport_template *ata_attach_transport(void)
757 {
758 	struct ata_internal *i;
759 	int count;
760 
761 	i = kzalloc(sizeof(struct ata_internal), GFP_KERNEL);
762 	if (!i)
763 		return NULL;
764 
765 	i->t.eh_strategy_handler	= ata_scsi_error;
766 	i->t.user_scan			= ata_scsi_user_scan;
767 
768 	i->t.host_attrs.ac.attrs = &i->port_attrs[0];
769 	i->t.host_attrs.ac.class = &ata_port_class.class;
770 	i->t.host_attrs.ac.match = ata_tport_match;
771 	transport_container_register(&i->t.host_attrs);
772 
773 	i->link_attr_cont.ac.class = &ata_link_class.class;
774 	i->link_attr_cont.ac.attrs = &i->link_attrs[0];
775 	i->link_attr_cont.ac.match = ata_tlink_match;
776 	transport_container_register(&i->link_attr_cont);
777 
778 	i->dev_attr_cont.ac.class = &ata_dev_class.class;
779 	i->dev_attr_cont.ac.attrs = &i->dev_attrs[0];
780 	i->dev_attr_cont.ac.match = ata_tdev_match;
781 	transport_container_register(&i->dev_attr_cont);
782 
783 	count = 0;
784 	SETUP_PORT_ATTRIBUTE(nr_pmp_links);
785 	SETUP_PORT_ATTRIBUTE(idle_irq);
786 	SETUP_PORT_ATTRIBUTE(port_no);
787 	BUG_ON(count > ATA_PORT_ATTRS);
788 	i->port_attrs[count] = NULL;
789 
790 	count = 0;
791 	SETUP_LINK_ATTRIBUTE(hw_sata_spd_limit);
792 	SETUP_LINK_ATTRIBUTE(sata_spd_limit);
793 	SETUP_LINK_ATTRIBUTE(sata_spd);
794 	BUG_ON(count > ATA_LINK_ATTRS);
795 	i->link_attrs[count] = NULL;
796 
797 	count = 0;
798 	SETUP_DEV_ATTRIBUTE(class);
799 	SETUP_DEV_ATTRIBUTE(pio_mode);
800 	SETUP_DEV_ATTRIBUTE(dma_mode);
801 	SETUP_DEV_ATTRIBUTE(xfer_mode);
802 	SETUP_DEV_ATTRIBUTE(spdn_cnt);
803 	SETUP_DEV_ATTRIBUTE(ering);
804 	SETUP_DEV_ATTRIBUTE(id);
805 	SETUP_DEV_ATTRIBUTE(gscr);
806 	SETUP_DEV_ATTRIBUTE(trim);
807 	BUG_ON(count > ATA_DEV_ATTRS);
808 	i->dev_attrs[count] = NULL;
809 
810 	return &i->t;
811 }
812 
813 /**
814  * ata_release_transport  --  release ATA transport template instance
815  * @t:		transport template instance
816  */
817 void ata_release_transport(struct scsi_transport_template *t)
818 {
819 	struct ata_internal *i = to_ata_internal(t);
820 
821 	transport_container_unregister(&i->t.host_attrs);
822 	transport_container_unregister(&i->link_attr_cont);
823 	transport_container_unregister(&i->dev_attr_cont);
824 
825 	kfree(i);
826 }
827 
828 __init int libata_transport_init(void)
829 {
830 	int error;
831 
832 	error = transport_class_register(&ata_link_class);
833 	if (error)
834 		goto out_unregister_transport;
835 	error = transport_class_register(&ata_port_class);
836 	if (error)
837 		goto out_unregister_link;
838 	error = transport_class_register(&ata_dev_class);
839 	if (error)
840 		goto out_unregister_port;
841 	return 0;
842 
843  out_unregister_port:
844 	transport_class_unregister(&ata_port_class);
845  out_unregister_link:
846 	transport_class_unregister(&ata_link_class);
847  out_unregister_transport:
848 	return error;
849 
850 }
851 
852 void __exit libata_transport_exit(void)
853 {
854 	transport_class_unregister(&ata_link_class);
855 	transport_class_unregister(&ata_port_class);
856 	transport_class_unregister(&ata_dev_class);
857 }
858