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v6.2
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  libata-eh.c - libata error handling
   4 *
   5 *  Copyright 2006 Tejun Heo <htejun@gmail.com>
   6 *
   7 *  libata documentation is available via 'make {ps|pdf}docs',
   8 *  as Documentation/driver-api/libata.rst
   9 *
  10 *  Hardware documentation available from http://www.t13.org/ and
  11 *  http://www.sata-io.org/
  12 */
  13
  14#include <linux/kernel.h>
  15#include <linux/blkdev.h>
  16#include <linux/export.h>
  17#include <linux/pci.h>
  18#include <scsi/scsi.h>
  19#include <scsi/scsi_host.h>
  20#include <scsi/scsi_eh.h>
  21#include <scsi/scsi_device.h>
  22#include <scsi/scsi_cmnd.h>
  23#include <scsi/scsi_dbg.h>
  24#include "../scsi/scsi_transport_api.h"
  25
  26#include <linux/libata.h>
  27
  28#include <trace/events/libata.h>
  29#include "libata.h"
  30
  31enum {
  32	/* speed down verdicts */
  33	ATA_EH_SPDN_NCQ_OFF		= (1 << 0),
  34	ATA_EH_SPDN_SPEED_DOWN		= (1 << 1),
  35	ATA_EH_SPDN_FALLBACK_TO_PIO	= (1 << 2),
  36	ATA_EH_SPDN_KEEP_ERRORS		= (1 << 3),
  37
  38	/* error flags */
  39	ATA_EFLAG_IS_IO			= (1 << 0),
  40	ATA_EFLAG_DUBIOUS_XFER		= (1 << 1),
  41	ATA_EFLAG_OLD_ER                = (1 << 31),
  42
  43	/* error categories */
  44	ATA_ECAT_NONE			= 0,
  45	ATA_ECAT_ATA_BUS		= 1,
  46	ATA_ECAT_TOUT_HSM		= 2,
  47	ATA_ECAT_UNK_DEV		= 3,
  48	ATA_ECAT_DUBIOUS_NONE		= 4,
  49	ATA_ECAT_DUBIOUS_ATA_BUS	= 5,
  50	ATA_ECAT_DUBIOUS_TOUT_HSM	= 6,
  51	ATA_ECAT_DUBIOUS_UNK_DEV	= 7,
  52	ATA_ECAT_NR			= 8,
  53
  54	ATA_EH_CMD_DFL_TIMEOUT		=  5000,
  55
  56	/* always put at least this amount of time between resets */
  57	ATA_EH_RESET_COOL_DOWN		=  5000,
  58
  59	/* Waiting in ->prereset can never be reliable.  It's
  60	 * sometimes nice to wait there but it can't be depended upon;
  61	 * otherwise, we wouldn't be resetting.  Just give it enough
  62	 * time for most drives to spin up.
  63	 */
  64	ATA_EH_PRERESET_TIMEOUT		= 10000,
  65	ATA_EH_FASTDRAIN_INTERVAL	=  3000,
  66
  67	ATA_EH_UA_TRIES			= 5,
  68
  69	/* probe speed down parameters, see ata_eh_schedule_probe() */
  70	ATA_EH_PROBE_TRIAL_INTERVAL	= 60000,	/* 1 min */
  71	ATA_EH_PROBE_TRIALS		= 2,
  72};
  73
  74/* The following table determines how we sequence resets.  Each entry
  75 * represents timeout for that try.  The first try can be soft or
  76 * hardreset.  All others are hardreset if available.  In most cases
  77 * the first reset w/ 10sec timeout should succeed.  Following entries
  78 * are mostly for error handling, hotplug and those outlier devices that
  79 * take an exceptionally long time to recover from reset.
  80 */
  81static const unsigned long ata_eh_reset_timeouts[] = {
  82	10000,	/* most drives spin up by 10sec */
  83	10000,	/* > 99% working drives spin up before 20sec */
  84	35000,	/* give > 30 secs of idleness for outlier devices */
  85	 5000,	/* and sweet one last chance */
  86	ULONG_MAX, /* > 1 min has elapsed, give up */
  87};
  88
  89static const unsigned int ata_eh_identify_timeouts[] = {
  90	 5000,	/* covers > 99% of successes and not too boring on failures */
  91	10000,  /* combined time till here is enough even for media access */
  92	30000,	/* for true idiots */
  93	UINT_MAX,
  94};
  95
  96static const unsigned int ata_eh_revalidate_timeouts[] = {
  97	15000,	/* Some drives are slow to read log pages when waking-up */
  98	15000,  /* combined time till here is enough even for media access */
  99	UINT_MAX,
 100};
 101
 102static const unsigned int ata_eh_flush_timeouts[] = {
 103	15000,	/* be generous with flush */
 104	15000,  /* ditto */
 105	30000,	/* and even more generous */
 106	UINT_MAX,
 107};
 108
 109static const unsigned int ata_eh_other_timeouts[] = {
 110	 5000,	/* same rationale as identify timeout */
 111	10000,	/* ditto */
 112	/* but no merciful 30sec for other commands, it just isn't worth it */
 113	UINT_MAX,
 114};
 115
 116struct ata_eh_cmd_timeout_ent {
 117	const u8		*commands;
 118	const unsigned int	*timeouts;
 119};
 120
 121/* The following table determines timeouts to use for EH internal
 122 * commands.  Each table entry is a command class and matches the
 123 * commands the entry applies to and the timeout table to use.
 124 *
 125 * On the retry after a command timed out, the next timeout value from
 126 * the table is used.  If the table doesn't contain further entries,
 127 * the last value is used.
 128 *
 129 * ehc->cmd_timeout_idx keeps track of which timeout to use per
 130 * command class, so if SET_FEATURES times out on the first try, the
 131 * next try will use the second timeout value only for that class.
 132 */
 133#define CMDS(cmds...)	(const u8 []){ cmds, 0 }
 134static const struct ata_eh_cmd_timeout_ent
 135ata_eh_cmd_timeout_table[ATA_EH_CMD_TIMEOUT_TABLE_SIZE] = {
 136	{ .commands = CMDS(ATA_CMD_ID_ATA, ATA_CMD_ID_ATAPI),
 137	  .timeouts = ata_eh_identify_timeouts, },
 138	{ .commands = CMDS(ATA_CMD_READ_LOG_EXT, ATA_CMD_READ_LOG_DMA_EXT),
 139	  .timeouts = ata_eh_revalidate_timeouts, },
 140	{ .commands = CMDS(ATA_CMD_READ_NATIVE_MAX, ATA_CMD_READ_NATIVE_MAX_EXT),
 141	  .timeouts = ata_eh_other_timeouts, },
 142	{ .commands = CMDS(ATA_CMD_SET_MAX, ATA_CMD_SET_MAX_EXT),
 143	  .timeouts = ata_eh_other_timeouts, },
 144	{ .commands = CMDS(ATA_CMD_SET_FEATURES),
 145	  .timeouts = ata_eh_other_timeouts, },
 146	{ .commands = CMDS(ATA_CMD_INIT_DEV_PARAMS),
 147	  .timeouts = ata_eh_other_timeouts, },
 148	{ .commands = CMDS(ATA_CMD_FLUSH, ATA_CMD_FLUSH_EXT),
 149	  .timeouts = ata_eh_flush_timeouts },
 
 
 150};
 151#undef CMDS
 152
 153static void __ata_port_freeze(struct ata_port *ap);
 154static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
 155			  struct ata_device **r_failed_dev);
 156#ifdef CONFIG_PM
 157static void ata_eh_handle_port_suspend(struct ata_port *ap);
 158static void ata_eh_handle_port_resume(struct ata_port *ap);
 159#else /* CONFIG_PM */
 160static void ata_eh_handle_port_suspend(struct ata_port *ap)
 161{ }
 162
 163static void ata_eh_handle_port_resume(struct ata_port *ap)
 164{ }
 165#endif /* CONFIG_PM */
 166
 167static __printf(2, 0) void __ata_ehi_pushv_desc(struct ata_eh_info *ehi,
 168				 const char *fmt, va_list args)
 169{
 170	ehi->desc_len += vscnprintf(ehi->desc + ehi->desc_len,
 171				     ATA_EH_DESC_LEN - ehi->desc_len,
 172				     fmt, args);
 173}
 174
 175/**
 176 *	__ata_ehi_push_desc - push error description without adding separator
 177 *	@ehi: target EHI
 178 *	@fmt: printf format string
 179 *
 180 *	Format string according to @fmt and append it to @ehi->desc.
 181 *
 182 *	LOCKING:
 183 *	spin_lock_irqsave(host lock)
 184 */
 185void __ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 186{
 187	va_list args;
 188
 189	va_start(args, fmt);
 190	__ata_ehi_pushv_desc(ehi, fmt, args);
 191	va_end(args);
 192}
 193EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
 194
 195/**
 196 *	ata_ehi_push_desc - push error description with separator
 197 *	@ehi: target EHI
 198 *	@fmt: printf format string
 199 *
 200 *	Format string according to @fmt and append it to @ehi->desc.
 201 *	If @ehi->desc is not empty, ", " is added in-between.
 202 *
 203 *	LOCKING:
 204 *	spin_lock_irqsave(host lock)
 205 */
 206void ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 207{
 208	va_list args;
 209
 210	if (ehi->desc_len)
 211		__ata_ehi_push_desc(ehi, ", ");
 212
 213	va_start(args, fmt);
 214	__ata_ehi_pushv_desc(ehi, fmt, args);
 215	va_end(args);
 216}
 217EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
 218
 219/**
 220 *	ata_ehi_clear_desc - clean error description
 221 *	@ehi: target EHI
 222 *
 223 *	Clear @ehi->desc.
 224 *
 225 *	LOCKING:
 226 *	spin_lock_irqsave(host lock)
 227 */
 228void ata_ehi_clear_desc(struct ata_eh_info *ehi)
 229{
 230	ehi->desc[0] = '\0';
 231	ehi->desc_len = 0;
 232}
 233EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
 234
 235/**
 236 *	ata_port_desc - append port description
 237 *	@ap: target ATA port
 238 *	@fmt: printf format string
 239 *
 240 *	Format string according to @fmt and append it to port
 241 *	description.  If port description is not empty, " " is added
 242 *	in-between.  This function is to be used while initializing
 243 *	ata_host.  The description is printed on host registration.
 244 *
 245 *	LOCKING:
 246 *	None.
 247 */
 248void ata_port_desc(struct ata_port *ap, const char *fmt, ...)
 249{
 250	va_list args;
 251
 252	WARN_ON(!(ap->pflags & ATA_PFLAG_INITIALIZING));
 253
 254	if (ap->link.eh_info.desc_len)
 255		__ata_ehi_push_desc(&ap->link.eh_info, " ");
 256
 257	va_start(args, fmt);
 258	__ata_ehi_pushv_desc(&ap->link.eh_info, fmt, args);
 259	va_end(args);
 260}
 261EXPORT_SYMBOL_GPL(ata_port_desc);
 262
 263#ifdef CONFIG_PCI
 264/**
 265 *	ata_port_pbar_desc - append PCI BAR description
 266 *	@ap: target ATA port
 267 *	@bar: target PCI BAR
 268 *	@offset: offset into PCI BAR
 269 *	@name: name of the area
 270 *
 271 *	If @offset is negative, this function formats a string which
 272 *	contains the name, address, size and type of the BAR and
 273 *	appends it to the port description.  If @offset is zero or
 274 *	positive, only name and offsetted address is appended.
 275 *
 276 *	LOCKING:
 277 *	None.
 278 */
 279void ata_port_pbar_desc(struct ata_port *ap, int bar, ssize_t offset,
 280			const char *name)
 281{
 282	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 283	char *type = "";
 284	unsigned long long start, len;
 285
 286	if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
 287		type = "m";
 288	else if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
 289		type = "i";
 290
 291	start = (unsigned long long)pci_resource_start(pdev, bar);
 292	len = (unsigned long long)pci_resource_len(pdev, bar);
 293
 294	if (offset < 0)
 295		ata_port_desc(ap, "%s %s%llu@0x%llx", name, type, len, start);
 296	else
 297		ata_port_desc(ap, "%s 0x%llx", name,
 298				start + (unsigned long long)offset);
 299}
 300EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
 301#endif /* CONFIG_PCI */
 302
 303static int ata_lookup_timeout_table(u8 cmd)
 304{
 305	int i;
 306
 307	for (i = 0; i < ATA_EH_CMD_TIMEOUT_TABLE_SIZE; i++) {
 308		const u8 *cur;
 309
 310		for (cur = ata_eh_cmd_timeout_table[i].commands; *cur; cur++)
 311			if (*cur == cmd)
 312				return i;
 313	}
 314
 315	return -1;
 316}
 317
 318/**
 319 *	ata_internal_cmd_timeout - determine timeout for an internal command
 320 *	@dev: target device
 321 *	@cmd: internal command to be issued
 322 *
 323 *	Determine timeout for internal command @cmd for @dev.
 324 *
 325 *	LOCKING:
 326 *	EH context.
 327 *
 328 *	RETURNS:
 329 *	Determined timeout.
 330 */
 331unsigned int ata_internal_cmd_timeout(struct ata_device *dev, u8 cmd)
 332{
 333	struct ata_eh_context *ehc = &dev->link->eh_context;
 334	int ent = ata_lookup_timeout_table(cmd);
 335	int idx;
 336
 337	if (ent < 0)
 338		return ATA_EH_CMD_DFL_TIMEOUT;
 339
 340	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 341	return ata_eh_cmd_timeout_table[ent].timeouts[idx];
 342}
 343
 344/**
 345 *	ata_internal_cmd_timed_out - notification for internal command timeout
 346 *	@dev: target device
 347 *	@cmd: internal command which timed out
 348 *
 349 *	Notify EH that internal command @cmd for @dev timed out.  This
 350 *	function should be called only for commands whose timeouts are
 351 *	determined using ata_internal_cmd_timeout().
 352 *
 353 *	LOCKING:
 354 *	EH context.
 355 */
 356void ata_internal_cmd_timed_out(struct ata_device *dev, u8 cmd)
 357{
 358	struct ata_eh_context *ehc = &dev->link->eh_context;
 359	int ent = ata_lookup_timeout_table(cmd);
 360	int idx;
 361
 362	if (ent < 0)
 363		return;
 364
 365	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 366	if (ata_eh_cmd_timeout_table[ent].timeouts[idx + 1] != UINT_MAX)
 367		ehc->cmd_timeout_idx[dev->devno][ent]++;
 368}
 369
 370static void ata_ering_record(struct ata_ering *ering, unsigned int eflags,
 371			     unsigned int err_mask)
 372{
 373	struct ata_ering_entry *ent;
 374
 375	WARN_ON(!err_mask);
 376
 377	ering->cursor++;
 378	ering->cursor %= ATA_ERING_SIZE;
 379
 380	ent = &ering->ring[ering->cursor];
 381	ent->eflags = eflags;
 382	ent->err_mask = err_mask;
 383	ent->timestamp = get_jiffies_64();
 384}
 385
 386static struct ata_ering_entry *ata_ering_top(struct ata_ering *ering)
 387{
 388	struct ata_ering_entry *ent = &ering->ring[ering->cursor];
 389
 390	if (ent->err_mask)
 391		return ent;
 392	return NULL;
 393}
 394
 395int ata_ering_map(struct ata_ering *ering,
 396		  int (*map_fn)(struct ata_ering_entry *, void *),
 397		  void *arg)
 398{
 399	int idx, rc = 0;
 400	struct ata_ering_entry *ent;
 401
 402	idx = ering->cursor;
 403	do {
 404		ent = &ering->ring[idx];
 405		if (!ent->err_mask)
 406			break;
 407		rc = map_fn(ent, arg);
 408		if (rc)
 409			break;
 410		idx = (idx - 1 + ATA_ERING_SIZE) % ATA_ERING_SIZE;
 411	} while (idx != ering->cursor);
 412
 413	return rc;
 414}
 415
 416static int ata_ering_clear_cb(struct ata_ering_entry *ent, void *void_arg)
 417{
 418	ent->eflags |= ATA_EFLAG_OLD_ER;
 419	return 0;
 420}
 421
 422static void ata_ering_clear(struct ata_ering *ering)
 423{
 424	ata_ering_map(ering, ata_ering_clear_cb, NULL);
 425}
 426
 427static unsigned int ata_eh_dev_action(struct ata_device *dev)
 428{
 429	struct ata_eh_context *ehc = &dev->link->eh_context;
 430
 431	return ehc->i.action | ehc->i.dev_action[dev->devno];
 432}
 433
 434static void ata_eh_clear_action(struct ata_link *link, struct ata_device *dev,
 435				struct ata_eh_info *ehi, unsigned int action)
 436{
 437	struct ata_device *tdev;
 438
 439	if (!dev) {
 440		ehi->action &= ~action;
 441		ata_for_each_dev(tdev, link, ALL)
 442			ehi->dev_action[tdev->devno] &= ~action;
 443	} else {
 444		/* doesn't make sense for port-wide EH actions */
 445		WARN_ON(!(action & ATA_EH_PERDEV_MASK));
 446
 447		/* break ehi->action into ehi->dev_action */
 448		if (ehi->action & action) {
 449			ata_for_each_dev(tdev, link, ALL)
 450				ehi->dev_action[tdev->devno] |=
 451					ehi->action & action;
 452			ehi->action &= ~action;
 453		}
 454
 455		/* turn off the specified per-dev action */
 456		ehi->dev_action[dev->devno] &= ~action;
 457	}
 458}
 459
 460/**
 461 *	ata_eh_acquire - acquire EH ownership
 462 *	@ap: ATA port to acquire EH ownership for
 463 *
 464 *	Acquire EH ownership for @ap.  This is the basic exclusion
 465 *	mechanism for ports sharing a host.  Only one port hanging off
 466 *	the same host can claim the ownership of EH.
 467 *
 468 *	LOCKING:
 469 *	EH context.
 470 */
 471void ata_eh_acquire(struct ata_port *ap)
 472{
 473	mutex_lock(&ap->host->eh_mutex);
 474	WARN_ON_ONCE(ap->host->eh_owner);
 475	ap->host->eh_owner = current;
 476}
 477
 478/**
 479 *	ata_eh_release - release EH ownership
 480 *	@ap: ATA port to release EH ownership for
 481 *
 482 *	Release EH ownership for @ap if the caller.  The caller must
 483 *	have acquired EH ownership using ata_eh_acquire() previously.
 484 *
 485 *	LOCKING:
 486 *	EH context.
 487 */
 488void ata_eh_release(struct ata_port *ap)
 489{
 490	WARN_ON_ONCE(ap->host->eh_owner != current);
 491	ap->host->eh_owner = NULL;
 492	mutex_unlock(&ap->host->eh_mutex);
 493}
 494
 
 
 
 
 
 
 
 
 
 
 
 
 495static void ata_eh_unload(struct ata_port *ap)
 496{
 497	struct ata_link *link;
 498	struct ata_device *dev;
 499	unsigned long flags;
 500
 501	/* Restore SControl IPM and SPD for the next driver and
 
 
 
 
 
 
 
 
 
 
 
 
 502	 * disable attached devices.
 503	 */
 504	ata_for_each_link(link, ap, PMP_FIRST) {
 505		sata_scr_write(link, SCR_CONTROL, link->saved_scontrol & 0xff0);
 506		ata_for_each_dev(dev, link, ALL)
 507			ata_dev_disable(dev);
 508	}
 509
 510	/* freeze and set UNLOADED */
 511	spin_lock_irqsave(ap->lock, flags);
 512
 513	ata_port_freeze(ap);			/* won't be thawed */
 514	ap->pflags &= ~ATA_PFLAG_EH_PENDING;	/* clear pending from freeze */
 515	ap->pflags |= ATA_PFLAG_UNLOADED;
 516
 517	spin_unlock_irqrestore(ap->lock, flags);
 518}
 519
 520/**
 521 *	ata_scsi_error - SCSI layer error handler callback
 522 *	@host: SCSI host on which error occurred
 523 *
 524 *	Handles SCSI-layer-thrown error events.
 525 *
 526 *	LOCKING:
 527 *	Inherited from SCSI layer (none, can sleep)
 528 *
 529 *	RETURNS:
 530 *	Zero.
 531 */
 532void ata_scsi_error(struct Scsi_Host *host)
 533{
 534	struct ata_port *ap = ata_shost_to_port(host);
 535	unsigned long flags;
 536	LIST_HEAD(eh_work_q);
 537
 538	spin_lock_irqsave(host->host_lock, flags);
 539	list_splice_init(&host->eh_cmd_q, &eh_work_q);
 540	spin_unlock_irqrestore(host->host_lock, flags);
 541
 542	ata_scsi_cmd_error_handler(host, ap, &eh_work_q);
 543
 544	/* If we timed raced normal completion and there is nothing to
 545	   recover nr_timedout == 0 why exactly are we doing error recovery ? */
 546	ata_scsi_port_error_handler(host, ap);
 547
 548	/* finish or retry handled scmd's and clean up */
 549	WARN_ON(!list_empty(&eh_work_q));
 550
 551}
 552
 553/**
 554 * ata_scsi_cmd_error_handler - error callback for a list of commands
 555 * @host:	scsi host containing the port
 556 * @ap:		ATA port within the host
 557 * @eh_work_q:	list of commands to process
 558 *
 559 * process the given list of commands and return those finished to the
 560 * ap->eh_done_q.  This function is the first part of the libata error
 561 * handler which processes a given list of failed commands.
 562 */
 563void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
 564				struct list_head *eh_work_q)
 565{
 566	int i;
 567	unsigned long flags;
 
 
 568
 569	/* make sure sff pio task is not running */
 570	ata_sff_flush_pio_task(ap);
 571
 572	/* synchronize with host lock and sort out timeouts */
 573
 574	/* For new EH, all qcs are finished in one of three ways -
 
 575	 * normal completion, error completion, and SCSI timeout.
 576	 * Both completions can race against SCSI timeout.  When normal
 577	 * completion wins, the qc never reaches EH.  When error
 578	 * completion wins, the qc has ATA_QCFLAG_FAILED set.
 579	 *
 580	 * When SCSI timeout wins, things are a bit more complex.
 581	 * Normal or error completion can occur after the timeout but
 582	 * before this point.  In such cases, both types of
 583	 * completions are honored.  A scmd is determined to have
 584	 * timed out iff its associated qc is active and not failed.
 585	 */
 586	spin_lock_irqsave(ap->lock, flags);
 587	if (ap->ops->error_handler) {
 588		struct scsi_cmnd *scmd, *tmp;
 589		int nr_timedout = 0;
 590
 591		/* This must occur under the ap->lock as we don't want
 592		   a polled recovery to race the real interrupt handler
 593
 594		   The lost_interrupt handler checks for any completed but
 595		   non-notified command and completes much like an IRQ handler.
 596
 597		   We then fall into the error recovery code which will treat
 598		   this as if normal completion won the race */
 599
 600		if (ap->ops->lost_interrupt)
 601			ap->ops->lost_interrupt(ap);
 
 
 
 
 
 
 
 602
 603		list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
 604			struct ata_queued_cmd *qc;
 605
 606			ata_qc_for_each_raw(ap, qc, i) {
 607				if (qc->flags & ATA_QCFLAG_ACTIVE &&
 608				    qc->scsicmd == scmd)
 609					break;
 610			}
 611
 612			if (i < ATA_MAX_QUEUE) {
 613				/* the scmd has an associated qc */
 614				if (!(qc->flags & ATA_QCFLAG_FAILED)) {
 615					/* which hasn't failed yet, timeout */
 616					qc->err_mask |= AC_ERR_TIMEOUT;
 617					qc->flags |= ATA_QCFLAG_FAILED;
 618					nr_timedout++;
 619				}
 620			} else {
 621				/* Normal completion occurred after
 622				 * SCSI timeout but before this point.
 623				 * Successfully complete it.
 624				 */
 625				scmd->retries = scmd->allowed;
 626				scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
 627			}
 
 
 
 
 
 
 
 628		}
 
 629
 630		/* If we have timed out qcs.  They belong to EH from
 631		 * this point but the state of the controller is
 632		 * unknown.  Freeze the port to make sure the IRQ
 633		 * handler doesn't diddle with those qcs.  This must
 634		 * be done atomically w.r.t. setting QCFLAG_FAILED.
 635		 */
 636		if (nr_timedout)
 637			__ata_port_freeze(ap);
 
 638
 
 
 639
 640		/* initialize eh_tries */
 641		ap->eh_tries = ATA_EH_MAX_TRIES;
 642	}
 643	spin_unlock_irqrestore(ap->lock, flags);
 644
 645}
 646EXPORT_SYMBOL(ata_scsi_cmd_error_handler);
 647
 648/**
 649 * ata_scsi_port_error_handler - recover the port after the commands
 650 * @host:	SCSI host containing the port
 651 * @ap:		the ATA port
 652 *
 653 * Handle the recovery of the port @ap after all the commands
 654 * have been recovered.
 655 */
 656void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap)
 657{
 658	unsigned long flags;
 
 659
 660	/* invoke error handler */
 661	if (ap->ops->error_handler) {
 662		struct ata_link *link;
 663
 664		/* acquire EH ownership */
 665		ata_eh_acquire(ap);
 666 repeat:
 667		/* kill fast drain timer */
 668		del_timer_sync(&ap->fastdrain_timer);
 669
 670		/* process port resume request */
 671		ata_eh_handle_port_resume(ap);
 672
 673		/* fetch & clear EH info */
 674		spin_lock_irqsave(ap->lock, flags);
 675
 676		ata_for_each_link(link, ap, HOST_FIRST) {
 677			struct ata_eh_context *ehc = &link->eh_context;
 678			struct ata_device *dev;
 679
 680			memset(&link->eh_context, 0, sizeof(link->eh_context));
 681			link->eh_context.i = link->eh_info;
 682			memset(&link->eh_info, 0, sizeof(link->eh_info));
 683
 684			ata_for_each_dev(dev, link, ENABLED) {
 685				int devno = dev->devno;
 686
 687				ehc->saved_xfer_mode[devno] = dev->xfer_mode;
 688				if (ata_ncq_enabled(dev))
 689					ehc->saved_ncq_enabled |= 1 << devno;
 690			}
 691		}
 692
 693		ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
 694		ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 695		ap->excl_link = NULL;	/* don't maintain exclusion over EH */
 696
 697		spin_unlock_irqrestore(ap->lock, flags);
 
 698
 699		/* invoke EH, skip if unloading or suspended */
 700		if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))
 701			ap->ops->error_handler(ap);
 702		else {
 703			/* if unloading, commence suicide */
 704			if ((ap->pflags & ATA_PFLAG_UNLOADING) &&
 705			    !(ap->pflags & ATA_PFLAG_UNLOADED))
 706				ata_eh_unload(ap);
 707			ata_eh_finish(ap);
 708		}
 709
 710		/* process port suspend request */
 711		ata_eh_handle_port_suspend(ap);
 712
 713		/* Exception might have happened after ->error_handler
 714		 * recovered the port but before this point.  Repeat
 715		 * EH in such case.
 716		 */
 717		spin_lock_irqsave(ap->lock, flags);
 718
 719		if (ap->pflags & ATA_PFLAG_EH_PENDING) {
 720			if (--ap->eh_tries) {
 721				spin_unlock_irqrestore(ap->lock, flags);
 722				goto repeat;
 723			}
 724			ata_port_err(ap,
 725				     "EH pending after %d tries, giving up\n",
 726				     ATA_EH_MAX_TRIES);
 727			ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 728		}
 
 729
 730		/* this run is complete, make sure EH info is clear */
 731		ata_for_each_link(link, ap, HOST_FIRST)
 732			memset(&link->eh_info, 0, sizeof(link->eh_info));
 733
 734		/* end eh (clear host_eh_scheduled) while holding
 735		 * ap->lock such that if exception occurs after this
 736		 * point but before EH completion, SCSI midlayer will
 737		 * re-initiate EH.
 738		 */
 739		ap->ops->end_eh(ap);
 740
 741		spin_unlock_irqrestore(ap->lock, flags);
 742		ata_eh_release(ap);
 743	} else {
 744		WARN_ON(ata_qc_from_tag(ap, ap->link.active_tag) == NULL);
 745		ap->ops->eng_timeout(ap);
 
 
 
 
 
 
 746	}
 747
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 748	scsi_eh_flush_done_q(&ap->eh_done_q);
 749
 750	/* clean up */
 751	spin_lock_irqsave(ap->lock, flags);
 752
 
 
 753	if (ap->pflags & ATA_PFLAG_LOADING)
 754		ap->pflags &= ~ATA_PFLAG_LOADING;
 755	else if ((ap->pflags & ATA_PFLAG_SCSI_HOTPLUG) &&
 756		!(ap->flags & ATA_FLAG_SAS_HOST))
 757		schedule_delayed_work(&ap->hotplug_task, 0);
 758
 759	if (ap->pflags & ATA_PFLAG_RECOVERED)
 760		ata_port_info(ap, "EH complete\n");
 761
 762	ap->pflags &= ~(ATA_PFLAG_SCSI_HOTPLUG | ATA_PFLAG_RECOVERED);
 763
 764	/* tell wait_eh that we're done */
 765	ap->pflags &= ~ATA_PFLAG_EH_IN_PROGRESS;
 766	wake_up_all(&ap->eh_wait_q);
 767
 768	spin_unlock_irqrestore(ap->lock, flags);
 769}
 770EXPORT_SYMBOL_GPL(ata_scsi_port_error_handler);
 771
 772/**
 773 *	ata_port_wait_eh - Wait for the currently pending EH to complete
 774 *	@ap: Port to wait EH for
 775 *
 776 *	Wait until the currently pending EH is complete.
 777 *
 778 *	LOCKING:
 779 *	Kernel thread context (may sleep).
 780 */
 781void ata_port_wait_eh(struct ata_port *ap)
 782{
 783	unsigned long flags;
 784	DEFINE_WAIT(wait);
 785
 786 retry:
 787	spin_lock_irqsave(ap->lock, flags);
 788
 789	while (ap->pflags & (ATA_PFLAG_EH_PENDING | ATA_PFLAG_EH_IN_PROGRESS)) {
 790		prepare_to_wait(&ap->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 791		spin_unlock_irqrestore(ap->lock, flags);
 792		schedule();
 793		spin_lock_irqsave(ap->lock, flags);
 794	}
 795	finish_wait(&ap->eh_wait_q, &wait);
 796
 797	spin_unlock_irqrestore(ap->lock, flags);
 798
 799	/* make sure SCSI EH is complete */
 800	if (scsi_host_in_recovery(ap->scsi_host)) {
 801		ata_msleep(ap, 10);
 802		goto retry;
 803	}
 804}
 805EXPORT_SYMBOL_GPL(ata_port_wait_eh);
 806
 807static unsigned int ata_eh_nr_in_flight(struct ata_port *ap)
 808{
 809	struct ata_queued_cmd *qc;
 810	unsigned int tag;
 811	unsigned int nr = 0;
 812
 813	/* count only non-internal commands */
 814	ata_qc_for_each(ap, qc, tag) {
 815		if (qc)
 816			nr++;
 817	}
 818
 819	return nr;
 820}
 821
 822void ata_eh_fastdrain_timerfn(struct timer_list *t)
 823{
 824	struct ata_port *ap = from_timer(ap, t, fastdrain_timer);
 825	unsigned long flags;
 826	unsigned int cnt;
 827
 828	spin_lock_irqsave(ap->lock, flags);
 829
 830	cnt = ata_eh_nr_in_flight(ap);
 831
 832	/* are we done? */
 833	if (!cnt)
 834		goto out_unlock;
 835
 836	if (cnt == ap->fastdrain_cnt) {
 837		struct ata_queued_cmd *qc;
 838		unsigned int tag;
 839
 840		/* No progress during the last interval, tag all
 841		 * in-flight qcs as timed out and freeze the port.
 842		 */
 843		ata_qc_for_each(ap, qc, tag) {
 844			if (qc)
 845				qc->err_mask |= AC_ERR_TIMEOUT;
 846		}
 847
 848		ata_port_freeze(ap);
 849	} else {
 850		/* some qcs have finished, give it another chance */
 851		ap->fastdrain_cnt = cnt;
 852		ap->fastdrain_timer.expires =
 853			ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 854		add_timer(&ap->fastdrain_timer);
 855	}
 856
 857 out_unlock:
 858	spin_unlock_irqrestore(ap->lock, flags);
 859}
 860
 861/**
 862 *	ata_eh_set_pending - set ATA_PFLAG_EH_PENDING and activate fast drain
 863 *	@ap: target ATA port
 864 *	@fastdrain: activate fast drain
 865 *
 866 *	Set ATA_PFLAG_EH_PENDING and activate fast drain if @fastdrain
 867 *	is non-zero and EH wasn't pending before.  Fast drain ensures
 868 *	that EH kicks in in timely manner.
 869 *
 870 *	LOCKING:
 871 *	spin_lock_irqsave(host lock)
 872 */
 873static void ata_eh_set_pending(struct ata_port *ap, int fastdrain)
 874{
 875	unsigned int cnt;
 876
 877	/* already scheduled? */
 878	if (ap->pflags & ATA_PFLAG_EH_PENDING)
 879		return;
 880
 881	ap->pflags |= ATA_PFLAG_EH_PENDING;
 882
 883	if (!fastdrain)
 884		return;
 885
 886	/* do we have in-flight qcs? */
 887	cnt = ata_eh_nr_in_flight(ap);
 888	if (!cnt)
 889		return;
 890
 891	/* activate fast drain */
 892	ap->fastdrain_cnt = cnt;
 893	ap->fastdrain_timer.expires =
 894		ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 895	add_timer(&ap->fastdrain_timer);
 896}
 897
 898/**
 899 *	ata_qc_schedule_eh - schedule qc for error handling
 900 *	@qc: command to schedule error handling for
 901 *
 902 *	Schedule error handling for @qc.  EH will kick in as soon as
 903 *	other commands are drained.
 904 *
 905 *	LOCKING:
 906 *	spin_lock_irqsave(host lock)
 907 */
 908void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
 909{
 910	struct ata_port *ap = qc->ap;
 911
 912	WARN_ON(!ap->ops->error_handler);
 913
 914	qc->flags |= ATA_QCFLAG_FAILED;
 915	ata_eh_set_pending(ap, 1);
 916
 917	/* The following will fail if timeout has already expired.
 918	 * ata_scsi_error() takes care of such scmds on EH entry.
 919	 * Note that ATA_QCFLAG_FAILED is unconditionally set after
 920	 * this function completes.
 921	 */
 922	blk_abort_request(scsi_cmd_to_rq(qc->scsicmd));
 923}
 924
 925/**
 926 * ata_std_sched_eh - non-libsas ata_ports issue eh with this common routine
 927 * @ap: ATA port to schedule EH for
 928 *
 929 *	LOCKING: inherited from ata_port_schedule_eh
 930 *	spin_lock_irqsave(host lock)
 931 */
 932void ata_std_sched_eh(struct ata_port *ap)
 933{
 934	WARN_ON(!ap->ops->error_handler);
 935
 936	if (ap->pflags & ATA_PFLAG_INITIALIZING)
 937		return;
 938
 939	ata_eh_set_pending(ap, 1);
 940	scsi_schedule_eh(ap->scsi_host);
 941
 942	trace_ata_std_sched_eh(ap);
 943}
 944EXPORT_SYMBOL_GPL(ata_std_sched_eh);
 945
 946/**
 947 * ata_std_end_eh - non-libsas ata_ports complete eh with this common routine
 948 * @ap: ATA port to end EH for
 949 *
 950 * In the libata object model there is a 1:1 mapping of ata_port to
 951 * shost, so host fields can be directly manipulated under ap->lock, in
 952 * the libsas case we need to hold a lock at the ha->level to coordinate
 953 * these events.
 954 *
 955 *	LOCKING:
 956 *	spin_lock_irqsave(host lock)
 957 */
 958void ata_std_end_eh(struct ata_port *ap)
 959{
 960	struct Scsi_Host *host = ap->scsi_host;
 961
 962	host->host_eh_scheduled = 0;
 963}
 964EXPORT_SYMBOL(ata_std_end_eh);
 965
 966
 967/**
 968 *	ata_port_schedule_eh - schedule error handling without a qc
 969 *	@ap: ATA port to schedule EH for
 970 *
 971 *	Schedule error handling for @ap.  EH will kick in as soon as
 972 *	all commands are drained.
 973 *
 974 *	LOCKING:
 975 *	spin_lock_irqsave(host lock)
 976 */
 977void ata_port_schedule_eh(struct ata_port *ap)
 978{
 979	/* see: ata_std_sched_eh, unless you know better */
 980	ap->ops->sched_eh(ap);
 981}
 982EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
 983
 984static int ata_do_link_abort(struct ata_port *ap, struct ata_link *link)
 985{
 986	struct ata_queued_cmd *qc;
 987	int tag, nr_aborted = 0;
 988
 989	WARN_ON(!ap->ops->error_handler);
 990
 991	/* we're gonna abort all commands, no need for fast drain */
 992	ata_eh_set_pending(ap, 0);
 993
 994	/* include internal tag in iteration */
 995	ata_qc_for_each_with_internal(ap, qc, tag) {
 996		if (qc && (!link || qc->dev->link == link)) {
 997			qc->flags |= ATA_QCFLAG_FAILED;
 998			ata_qc_complete(qc);
 999			nr_aborted++;
1000		}
1001	}
1002
1003	if (!nr_aborted)
1004		ata_port_schedule_eh(ap);
1005
1006	return nr_aborted;
1007}
1008
1009/**
1010 *	ata_link_abort - abort all qc's on the link
1011 *	@link: ATA link to abort qc's for
1012 *
1013 *	Abort all active qc's active on @link and schedule EH.
1014 *
1015 *	LOCKING:
1016 *	spin_lock_irqsave(host lock)
1017 *
1018 *	RETURNS:
1019 *	Number of aborted qc's.
1020 */
1021int ata_link_abort(struct ata_link *link)
1022{
1023	return ata_do_link_abort(link->ap, link);
1024}
1025EXPORT_SYMBOL_GPL(ata_link_abort);
1026
1027/**
1028 *	ata_port_abort - abort all qc's on the port
1029 *	@ap: ATA port to abort qc's for
1030 *
1031 *	Abort all active qc's of @ap and schedule EH.
1032 *
1033 *	LOCKING:
1034 *	spin_lock_irqsave(host_set lock)
1035 *
1036 *	RETURNS:
1037 *	Number of aborted qc's.
1038 */
1039int ata_port_abort(struct ata_port *ap)
1040{
1041	return ata_do_link_abort(ap, NULL);
1042}
1043EXPORT_SYMBOL_GPL(ata_port_abort);
1044
1045/**
1046 *	__ata_port_freeze - freeze port
1047 *	@ap: ATA port to freeze
1048 *
1049 *	This function is called when HSM violation or some other
1050 *	condition disrupts normal operation of the port.  Frozen port
1051 *	is not allowed to perform any operation until the port is
1052 *	thawed, which usually follows a successful reset.
1053 *
1054 *	ap->ops->freeze() callback can be used for freezing the port
1055 *	hardware-wise (e.g. mask interrupt and stop DMA engine).  If a
1056 *	port cannot be frozen hardware-wise, the interrupt handler
1057 *	must ack and clear interrupts unconditionally while the port
1058 *	is frozen.
1059 *
1060 *	LOCKING:
1061 *	spin_lock_irqsave(host lock)
1062 */
1063static void __ata_port_freeze(struct ata_port *ap)
1064{
1065	WARN_ON(!ap->ops->error_handler);
1066
1067	if (ap->ops->freeze)
1068		ap->ops->freeze(ap);
1069
1070	ap->pflags |= ATA_PFLAG_FROZEN;
1071
1072	trace_ata_port_freeze(ap);
1073}
1074
1075/**
1076 *	ata_port_freeze - abort & freeze port
1077 *	@ap: ATA port to freeze
1078 *
1079 *	Abort and freeze @ap.  The freeze operation must be called
1080 *	first, because some hardware requires special operations
1081 *	before the taskfile registers are accessible.
1082 *
1083 *	LOCKING:
1084 *	spin_lock_irqsave(host lock)
1085 *
1086 *	RETURNS:
1087 *	Number of aborted commands.
1088 */
1089int ata_port_freeze(struct ata_port *ap)
1090{
1091	WARN_ON(!ap->ops->error_handler);
1092
1093	__ata_port_freeze(ap);
1094
1095	return ata_port_abort(ap);
1096}
1097EXPORT_SYMBOL_GPL(ata_port_freeze);
1098
1099/**
1100 *	ata_eh_freeze_port - EH helper to freeze port
1101 *	@ap: ATA port to freeze
1102 *
1103 *	Freeze @ap.
1104 *
1105 *	LOCKING:
1106 *	None.
1107 */
1108void ata_eh_freeze_port(struct ata_port *ap)
1109{
1110	unsigned long flags;
1111
1112	if (!ap->ops->error_handler)
1113		return;
1114
1115	spin_lock_irqsave(ap->lock, flags);
1116	__ata_port_freeze(ap);
1117	spin_unlock_irqrestore(ap->lock, flags);
1118}
1119EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
1120
1121/**
1122 *	ata_eh_thaw_port - EH helper to thaw port
1123 *	@ap: ATA port to thaw
1124 *
1125 *	Thaw frozen port @ap.
1126 *
1127 *	LOCKING:
1128 *	None.
1129 */
1130void ata_eh_thaw_port(struct ata_port *ap)
1131{
1132	unsigned long flags;
1133
1134	if (!ap->ops->error_handler)
1135		return;
1136
1137	spin_lock_irqsave(ap->lock, flags);
1138
1139	ap->pflags &= ~ATA_PFLAG_FROZEN;
1140
1141	if (ap->ops->thaw)
1142		ap->ops->thaw(ap);
1143
1144	spin_unlock_irqrestore(ap->lock, flags);
1145
1146	trace_ata_port_thaw(ap);
1147}
1148
1149static void ata_eh_scsidone(struct scsi_cmnd *scmd)
1150{
1151	/* nada */
1152}
1153
1154static void __ata_eh_qc_complete(struct ata_queued_cmd *qc)
1155{
1156	struct ata_port *ap = qc->ap;
1157	struct scsi_cmnd *scmd = qc->scsicmd;
1158	unsigned long flags;
1159
1160	spin_lock_irqsave(ap->lock, flags);
1161	qc->scsidone = ata_eh_scsidone;
1162	__ata_qc_complete(qc);
1163	WARN_ON(ata_tag_valid(qc->tag));
1164	spin_unlock_irqrestore(ap->lock, flags);
1165
1166	scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
1167}
1168
1169/**
1170 *	ata_eh_qc_complete - Complete an active ATA command from EH
1171 *	@qc: Command to complete
1172 *
1173 *	Indicate to the mid and upper layers that an ATA command has
1174 *	completed.  To be used from EH.
1175 */
1176void ata_eh_qc_complete(struct ata_queued_cmd *qc)
1177{
1178	struct scsi_cmnd *scmd = qc->scsicmd;
1179	scmd->retries = scmd->allowed;
1180	__ata_eh_qc_complete(qc);
1181}
1182
1183/**
1184 *	ata_eh_qc_retry - Tell midlayer to retry an ATA command after EH
1185 *	@qc: Command to retry
1186 *
1187 *	Indicate to the mid and upper layers that an ATA command
1188 *	should be retried.  To be used from EH.
1189 *
1190 *	SCSI midlayer limits the number of retries to scmd->allowed.
1191 *	scmd->allowed is incremented for commands which get retried
1192 *	due to unrelated failures (qc->err_mask is zero).
1193 */
1194void ata_eh_qc_retry(struct ata_queued_cmd *qc)
1195{
1196	struct scsi_cmnd *scmd = qc->scsicmd;
1197	if (!qc->err_mask)
1198		scmd->allowed++;
1199	__ata_eh_qc_complete(qc);
1200}
1201
1202/**
1203 *	ata_dev_disable - disable ATA device
1204 *	@dev: ATA device to disable
1205 *
1206 *	Disable @dev.
1207 *
1208 *	Locking:
1209 *	EH context.
1210 */
1211void ata_dev_disable(struct ata_device *dev)
1212{
1213	if (!ata_dev_enabled(dev))
1214		return;
1215
1216	ata_dev_warn(dev, "disable device\n");
1217	ata_acpi_on_disable(dev);
1218	ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 | ATA_DNXFER_QUIET);
1219	dev->class++;
1220
1221	/* From now till the next successful probe, ering is used to
1222	 * track probe failures.  Clear accumulated device error info.
1223	 */
1224	ata_ering_clear(&dev->ering);
1225}
1226EXPORT_SYMBOL_GPL(ata_dev_disable);
1227
1228/**
1229 *	ata_eh_detach_dev - detach ATA device
1230 *	@dev: ATA device to detach
1231 *
1232 *	Detach @dev.
1233 *
1234 *	LOCKING:
1235 *	None.
1236 */
1237void ata_eh_detach_dev(struct ata_device *dev)
1238{
1239	struct ata_link *link = dev->link;
1240	struct ata_port *ap = link->ap;
1241	struct ata_eh_context *ehc = &link->eh_context;
1242	unsigned long flags;
1243
1244	ata_dev_disable(dev);
 
 
 
 
 
 
 
1245
1246	spin_lock_irqsave(ap->lock, flags);
1247
1248	dev->flags &= ~ATA_DFLAG_DETACH;
1249
1250	if (ata_scsi_offline_dev(dev)) {
1251		dev->flags |= ATA_DFLAG_DETACHED;
1252		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
1253	}
1254
1255	/* clear per-dev EH info */
1256	ata_eh_clear_action(link, dev, &link->eh_info, ATA_EH_PERDEV_MASK);
1257	ata_eh_clear_action(link, dev, &link->eh_context.i, ATA_EH_PERDEV_MASK);
1258	ehc->saved_xfer_mode[dev->devno] = 0;
1259	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
1260
1261	spin_unlock_irqrestore(ap->lock, flags);
1262}
1263
1264/**
1265 *	ata_eh_about_to_do - about to perform eh_action
1266 *	@link: target ATA link
1267 *	@dev: target ATA dev for per-dev action (can be NULL)
1268 *	@action: action about to be performed
1269 *
1270 *	Called just before performing EH actions to clear related bits
1271 *	in @link->eh_info such that eh actions are not unnecessarily
1272 *	repeated.
1273 *
1274 *	LOCKING:
1275 *	None.
1276 */
1277void ata_eh_about_to_do(struct ata_link *link, struct ata_device *dev,
1278			unsigned int action)
1279{
1280	struct ata_port *ap = link->ap;
1281	struct ata_eh_info *ehi = &link->eh_info;
1282	struct ata_eh_context *ehc = &link->eh_context;
1283	unsigned long flags;
1284
1285	trace_ata_eh_about_to_do(link, dev ? dev->devno : 0, action);
1286
1287	spin_lock_irqsave(ap->lock, flags);
1288
1289	ata_eh_clear_action(link, dev, ehi, action);
1290
1291	/* About to take EH action, set RECOVERED.  Ignore actions on
1292	 * slave links as master will do them again.
1293	 */
1294	if (!(ehc->i.flags & ATA_EHI_QUIET) && link != ap->slave_link)
1295		ap->pflags |= ATA_PFLAG_RECOVERED;
1296
1297	spin_unlock_irqrestore(ap->lock, flags);
1298}
1299
1300/**
1301 *	ata_eh_done - EH action complete
1302 *	@link: ATA link for which EH actions are complete
1303 *	@dev: target ATA dev for per-dev action (can be NULL)
1304 *	@action: action just completed
1305 *
1306 *	Called right after performing EH actions to clear related bits
1307 *	in @link->eh_context.
1308 *
1309 *	LOCKING:
1310 *	None.
1311 */
1312void ata_eh_done(struct ata_link *link, struct ata_device *dev,
1313		 unsigned int action)
1314{
1315	struct ata_eh_context *ehc = &link->eh_context;
1316
1317	trace_ata_eh_done(link, dev ? dev->devno : 0, action);
1318
1319	ata_eh_clear_action(link, dev, &ehc->i, action);
1320}
1321
1322/**
1323 *	ata_err_string - convert err_mask to descriptive string
1324 *	@err_mask: error mask to convert to string
1325 *
1326 *	Convert @err_mask to descriptive string.  Errors are
1327 *	prioritized according to severity and only the most severe
1328 *	error is reported.
1329 *
1330 *	LOCKING:
1331 *	None.
1332 *
1333 *	RETURNS:
1334 *	Descriptive string for @err_mask
1335 */
1336static const char *ata_err_string(unsigned int err_mask)
1337{
1338	if (err_mask & AC_ERR_HOST_BUS)
1339		return "host bus error";
1340	if (err_mask & AC_ERR_ATA_BUS)
1341		return "ATA bus error";
1342	if (err_mask & AC_ERR_TIMEOUT)
1343		return "timeout";
1344	if (err_mask & AC_ERR_HSM)
1345		return "HSM violation";
1346	if (err_mask & AC_ERR_SYSTEM)
1347		return "internal error";
1348	if (err_mask & AC_ERR_MEDIA)
1349		return "media error";
1350	if (err_mask & AC_ERR_INVALID)
1351		return "invalid argument";
1352	if (err_mask & AC_ERR_DEV)
1353		return "device error";
1354	if (err_mask & AC_ERR_NCQ)
1355		return "NCQ error";
1356	if (err_mask & AC_ERR_NODEV_HINT)
1357		return "Polling detection error";
1358	return "unknown error";
1359}
1360
1361/**
1362 *	atapi_eh_tur - perform ATAPI TEST_UNIT_READY
1363 *	@dev: target ATAPI device
1364 *	@r_sense_key: out parameter for sense_key
1365 *
1366 *	Perform ATAPI TEST_UNIT_READY.
1367 *
1368 *	LOCKING:
1369 *	EH context (may sleep).
1370 *
1371 *	RETURNS:
1372 *	0 on success, AC_ERR_* mask on failure.
1373 */
1374unsigned int atapi_eh_tur(struct ata_device *dev, u8 *r_sense_key)
1375{
1376	u8 cdb[ATAPI_CDB_LEN] = { TEST_UNIT_READY, 0, 0, 0, 0, 0 };
1377	struct ata_taskfile tf;
1378	unsigned int err_mask;
1379
1380	ata_tf_init(dev, &tf);
1381
1382	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1383	tf.command = ATA_CMD_PACKET;
1384	tf.protocol = ATAPI_PROT_NODATA;
1385
1386	err_mask = ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
1387	if (err_mask == AC_ERR_DEV)
1388		*r_sense_key = tf.error >> 4;
1389	return err_mask;
1390}
1391
1392/**
1393 *	ata_eh_request_sense - perform REQUEST_SENSE_DATA_EXT
1394 *	@qc: qc to perform REQUEST_SENSE_SENSE_DATA_EXT to
1395 *
1396 *	Perform REQUEST_SENSE_DATA_EXT after the device reported CHECK
1397 *	SENSE.  This function is an EH helper.
1398 *
1399 *	LOCKING:
1400 *	Kernel thread context (may sleep).
 
 
 
1401 */
1402static void ata_eh_request_sense(struct ata_queued_cmd *qc)
1403{
1404	struct scsi_cmnd *cmd = qc->scsicmd;
1405	struct ata_device *dev = qc->dev;
1406	struct ata_taskfile tf;
1407	unsigned int err_mask;
1408
1409	if (ata_port_is_frozen(qc->ap)) {
1410		ata_dev_warn(dev, "sense data available but port frozen\n");
1411		return;
1412	}
1413
1414	if (!cmd || qc->flags & ATA_QCFLAG_SENSE_VALID)
1415		return;
1416
1417	if (!ata_id_sense_reporting_enabled(dev->id)) {
1418		ata_dev_warn(qc->dev, "sense data reporting disabled\n");
1419		return;
1420	}
1421
1422	ata_tf_init(dev, &tf);
1423	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1424	tf.flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
1425	tf.command = ATA_CMD_REQ_SENSE_DATA;
1426	tf.protocol = ATA_PROT_NODATA;
1427
1428	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1429	/* Ignore err_mask; ATA_ERR might be set */
1430	if (tf.status & ATA_SENSE) {
1431		if (ata_scsi_sense_is_valid(tf.lbah, tf.lbam, tf.lbal)) {
1432			ata_scsi_set_sense(dev, cmd, tf.lbah, tf.lbam, tf.lbal);
 
 
 
1433			qc->flags |= ATA_QCFLAG_SENSE_VALID;
 
1434		}
1435	} else {
1436		ata_dev_warn(dev, "request sense failed stat %02x emask %x\n",
1437			     tf.status, err_mask);
1438	}
 
 
1439}
1440
1441/**
1442 *	atapi_eh_request_sense - perform ATAPI REQUEST_SENSE
1443 *	@dev: device to perform REQUEST_SENSE to
1444 *	@sense_buf: result sense data buffer (SCSI_SENSE_BUFFERSIZE bytes long)
1445 *	@dfl_sense_key: default sense key to use
1446 *
1447 *	Perform ATAPI REQUEST_SENSE after the device reported CHECK
1448 *	SENSE.  This function is EH helper.
1449 *
1450 *	LOCKING:
1451 *	Kernel thread context (may sleep).
1452 *
1453 *	RETURNS:
1454 *	0 on success, AC_ERR_* mask on failure
1455 */
1456unsigned int atapi_eh_request_sense(struct ata_device *dev,
1457					   u8 *sense_buf, u8 dfl_sense_key)
1458{
1459	u8 cdb[ATAPI_CDB_LEN] =
1460		{ REQUEST_SENSE, 0, 0, 0, SCSI_SENSE_BUFFERSIZE, 0 };
1461	struct ata_port *ap = dev->link->ap;
1462	struct ata_taskfile tf;
1463
1464	memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
1465
1466	/* initialize sense_buf with the error register,
1467	 * for the case where they are -not- overwritten
1468	 */
1469	sense_buf[0] = 0x70;
1470	sense_buf[2] = dfl_sense_key;
1471
1472	/* some devices time out if garbage left in tf */
1473	ata_tf_init(dev, &tf);
1474
1475	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1476	tf.command = ATA_CMD_PACKET;
1477
1478	/* is it pointless to prefer PIO for "safety reasons"? */
1479	if (ap->flags & ATA_FLAG_PIO_DMA) {
1480		tf.protocol = ATAPI_PROT_DMA;
1481		tf.feature |= ATAPI_PKT_DMA;
1482	} else {
1483		tf.protocol = ATAPI_PROT_PIO;
1484		tf.lbam = SCSI_SENSE_BUFFERSIZE;
1485		tf.lbah = 0;
1486	}
1487
1488	return ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
1489				 sense_buf, SCSI_SENSE_BUFFERSIZE, 0);
1490}
1491
1492/**
1493 *	ata_eh_analyze_serror - analyze SError for a failed port
1494 *	@link: ATA link to analyze SError for
1495 *
1496 *	Analyze SError if available and further determine cause of
1497 *	failure.
1498 *
1499 *	LOCKING:
1500 *	None.
1501 */
1502static void ata_eh_analyze_serror(struct ata_link *link)
1503{
1504	struct ata_eh_context *ehc = &link->eh_context;
1505	u32 serror = ehc->i.serror;
1506	unsigned int err_mask = 0, action = 0;
1507	u32 hotplug_mask;
1508
1509	if (serror & (SERR_PERSISTENT | SERR_DATA)) {
1510		err_mask |= AC_ERR_ATA_BUS;
1511		action |= ATA_EH_RESET;
1512	}
1513	if (serror & SERR_PROTOCOL) {
1514		err_mask |= AC_ERR_HSM;
1515		action |= ATA_EH_RESET;
1516	}
1517	if (serror & SERR_INTERNAL) {
1518		err_mask |= AC_ERR_SYSTEM;
1519		action |= ATA_EH_RESET;
1520	}
1521
1522	/* Determine whether a hotplug event has occurred.  Both
1523	 * SError.N/X are considered hotplug events for enabled or
1524	 * host links.  For disabled PMP links, only N bit is
1525	 * considered as X bit is left at 1 for link plugging.
1526	 */
1527	if (link->lpm_policy > ATA_LPM_MAX_POWER)
1528		hotplug_mask = 0;	/* hotplug doesn't work w/ LPM */
1529	else if (!(link->flags & ATA_LFLAG_DISABLED) || ata_is_host_link(link))
1530		hotplug_mask = SERR_PHYRDY_CHG | SERR_DEV_XCHG;
1531	else
1532		hotplug_mask = SERR_PHYRDY_CHG;
1533
1534	if (serror & hotplug_mask)
1535		ata_ehi_hotplugged(&ehc->i);
1536
1537	ehc->i.err_mask |= err_mask;
1538	ehc->i.action |= action;
1539}
1540
1541/**
1542 *	ata_eh_analyze_tf - analyze taskfile of a failed qc
1543 *	@qc: qc to analyze
1544 *
1545 *	Analyze taskfile of @qc and further determine cause of
1546 *	failure.  This function also requests ATAPI sense data if
1547 *	available.
1548 *
1549 *	LOCKING:
1550 *	Kernel thread context (may sleep).
1551 *
1552 *	RETURNS:
1553 *	Determined recovery action
1554 */
1555static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc)
1556{
1557	const struct ata_taskfile *tf = &qc->result_tf;
1558	unsigned int tmp, action = 0;
1559	u8 stat = tf->status, err = tf->error;
1560
1561	if ((stat & (ATA_BUSY | ATA_DRQ | ATA_DRDY)) != ATA_DRDY) {
1562		qc->err_mask |= AC_ERR_HSM;
1563		return ATA_EH_RESET;
1564	}
1565
1566	if (stat & (ATA_ERR | ATA_DF)) {
1567		qc->err_mask |= AC_ERR_DEV;
1568		/*
1569		 * Sense data reporting does not work if the
1570		 * device fault bit is set.
1571		 */
1572		if (stat & ATA_DF)
1573			stat &= ~ATA_SENSE;
1574	} else {
1575		return 0;
1576	}
1577
1578	switch (qc->dev->class) {
1579	case ATA_DEV_ATA:
1580	case ATA_DEV_ZAC:
1581		/*
1582		 * Fetch the sense data explicitly if:
1583		 * -It was a non-NCQ command that failed, or
1584		 * -It was a NCQ command that failed, but the sense data
1585		 *  was not included in the NCQ command error log
1586		 *  (i.e. NCQ autosense is not supported by the device).
1587		 */
1588		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID) && (stat & ATA_SENSE))
1589			ata_eh_request_sense(qc);
 
1590		if (err & ATA_ICRC)
1591			qc->err_mask |= AC_ERR_ATA_BUS;
1592		if (err & (ATA_UNC | ATA_AMNF))
1593			qc->err_mask |= AC_ERR_MEDIA;
1594		if (err & ATA_IDNF)
1595			qc->err_mask |= AC_ERR_INVALID;
1596		break;
1597
1598	case ATA_DEV_ATAPI:
1599		if (!ata_port_is_frozen(qc->ap)) {
1600			tmp = atapi_eh_request_sense(qc->dev,
1601						qc->scsicmd->sense_buffer,
1602						qc->result_tf.error >> 4);
1603			if (!tmp)
1604				qc->flags |= ATA_QCFLAG_SENSE_VALID;
1605			else
1606				qc->err_mask |= tmp;
1607		}
1608	}
1609
1610	if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
1611		enum scsi_disposition ret = scsi_check_sense(qc->scsicmd);
1612		/*
1613		 * SUCCESS here means that the sense code could be
1614		 * evaluated and should be passed to the upper layers
1615		 * for correct evaluation.
1616		 * FAILED means the sense code could not be interpreted
1617		 * and the device would need to be reset.
1618		 * NEEDS_RETRY and ADD_TO_MLQUEUE means that the
1619		 * command would need to be retried.
1620		 */
1621		if (ret == NEEDS_RETRY || ret == ADD_TO_MLQUEUE) {
1622			qc->flags |= ATA_QCFLAG_RETRY;
1623			qc->err_mask |= AC_ERR_OTHER;
1624		} else if (ret != SUCCESS) {
1625			qc->err_mask |= AC_ERR_HSM;
1626		}
1627	}
1628	if (qc->err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT | AC_ERR_ATA_BUS))
1629		action |= ATA_EH_RESET;
1630
1631	return action;
1632}
1633
1634static int ata_eh_categorize_error(unsigned int eflags, unsigned int err_mask,
1635				   int *xfer_ok)
1636{
1637	int base = 0;
1638
1639	if (!(eflags & ATA_EFLAG_DUBIOUS_XFER))
1640		*xfer_ok = 1;
1641
1642	if (!*xfer_ok)
1643		base = ATA_ECAT_DUBIOUS_NONE;
1644
1645	if (err_mask & AC_ERR_ATA_BUS)
1646		return base + ATA_ECAT_ATA_BUS;
1647
1648	if (err_mask & AC_ERR_TIMEOUT)
1649		return base + ATA_ECAT_TOUT_HSM;
1650
1651	if (eflags & ATA_EFLAG_IS_IO) {
1652		if (err_mask & AC_ERR_HSM)
1653			return base + ATA_ECAT_TOUT_HSM;
1654		if ((err_mask &
1655		     (AC_ERR_DEV|AC_ERR_MEDIA|AC_ERR_INVALID)) == AC_ERR_DEV)
1656			return base + ATA_ECAT_UNK_DEV;
1657	}
1658
1659	return 0;
1660}
1661
1662struct speed_down_verdict_arg {
1663	u64 since;
1664	int xfer_ok;
1665	int nr_errors[ATA_ECAT_NR];
1666};
1667
1668static int speed_down_verdict_cb(struct ata_ering_entry *ent, void *void_arg)
1669{
1670	struct speed_down_verdict_arg *arg = void_arg;
1671	int cat;
1672
1673	if ((ent->eflags & ATA_EFLAG_OLD_ER) || (ent->timestamp < arg->since))
1674		return -1;
1675
1676	cat = ata_eh_categorize_error(ent->eflags, ent->err_mask,
1677				      &arg->xfer_ok);
1678	arg->nr_errors[cat]++;
1679
1680	return 0;
1681}
1682
1683/**
1684 *	ata_eh_speed_down_verdict - Determine speed down verdict
1685 *	@dev: Device of interest
1686 *
1687 *	This function examines error ring of @dev and determines
1688 *	whether NCQ needs to be turned off, transfer speed should be
1689 *	stepped down, or falling back to PIO is necessary.
1690 *
1691 *	ECAT_ATA_BUS	: ATA_BUS error for any command
1692 *
1693 *	ECAT_TOUT_HSM	: TIMEOUT for any command or HSM violation for
1694 *			  IO commands
1695 *
1696 *	ECAT_UNK_DEV	: Unknown DEV error for IO commands
1697 *
1698 *	ECAT_DUBIOUS_*	: Identical to above three but occurred while
1699 *			  data transfer hasn't been verified.
1700 *
1701 *	Verdicts are
1702 *
1703 *	NCQ_OFF		: Turn off NCQ.
1704 *
1705 *	SPEED_DOWN	: Speed down transfer speed but don't fall back
1706 *			  to PIO.
1707 *
1708 *	FALLBACK_TO_PIO	: Fall back to PIO.
1709 *
1710 *	Even if multiple verdicts are returned, only one action is
1711 *	taken per error.  An action triggered by non-DUBIOUS errors
1712 *	clears ering, while one triggered by DUBIOUS_* errors doesn't.
1713 *	This is to expedite speed down decisions right after device is
1714 *	initially configured.
1715 *
1716 *	The following are speed down rules.  #1 and #2 deal with
1717 *	DUBIOUS errors.
1718 *
1719 *	1. If more than one DUBIOUS_ATA_BUS or DUBIOUS_TOUT_HSM errors
1720 *	   occurred during last 5 mins, SPEED_DOWN and FALLBACK_TO_PIO.
1721 *
1722 *	2. If more than one DUBIOUS_TOUT_HSM or DUBIOUS_UNK_DEV errors
1723 *	   occurred during last 5 mins, NCQ_OFF.
1724 *
1725 *	3. If more than 8 ATA_BUS, TOUT_HSM or UNK_DEV errors
1726 *	   occurred during last 5 mins, FALLBACK_TO_PIO
1727 *
1728 *	4. If more than 3 TOUT_HSM or UNK_DEV errors occurred
1729 *	   during last 10 mins, NCQ_OFF.
1730 *
1731 *	5. If more than 3 ATA_BUS or TOUT_HSM errors, or more than 6
1732 *	   UNK_DEV errors occurred during last 10 mins, SPEED_DOWN.
1733 *
1734 *	LOCKING:
1735 *	Inherited from caller.
1736 *
1737 *	RETURNS:
1738 *	OR of ATA_EH_SPDN_* flags.
1739 */
1740static unsigned int ata_eh_speed_down_verdict(struct ata_device *dev)
1741{
1742	const u64 j5mins = 5LLU * 60 * HZ, j10mins = 10LLU * 60 * HZ;
1743	u64 j64 = get_jiffies_64();
1744	struct speed_down_verdict_arg arg;
1745	unsigned int verdict = 0;
1746
1747	/* scan past 5 mins of error history */
1748	memset(&arg, 0, sizeof(arg));
1749	arg.since = j64 - min(j64, j5mins);
1750	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1751
1752	if (arg.nr_errors[ATA_ECAT_DUBIOUS_ATA_BUS] +
1753	    arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] > 1)
1754		verdict |= ATA_EH_SPDN_SPEED_DOWN |
1755			ATA_EH_SPDN_FALLBACK_TO_PIO | ATA_EH_SPDN_KEEP_ERRORS;
1756
1757	if (arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] +
1758	    arg.nr_errors[ATA_ECAT_DUBIOUS_UNK_DEV] > 1)
1759		verdict |= ATA_EH_SPDN_NCQ_OFF | ATA_EH_SPDN_KEEP_ERRORS;
1760
1761	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1762	    arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1763	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1764		verdict |= ATA_EH_SPDN_FALLBACK_TO_PIO;
1765
1766	/* scan past 10 mins of error history */
1767	memset(&arg, 0, sizeof(arg));
1768	arg.since = j64 - min(j64, j10mins);
1769	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1770
1771	if (arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1772	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 3)
1773		verdict |= ATA_EH_SPDN_NCQ_OFF;
1774
1775	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1776	    arg.nr_errors[ATA_ECAT_TOUT_HSM] > 3 ||
1777	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1778		verdict |= ATA_EH_SPDN_SPEED_DOWN;
1779
1780	return verdict;
1781}
1782
1783/**
1784 *	ata_eh_speed_down - record error and speed down if necessary
1785 *	@dev: Failed device
1786 *	@eflags: mask of ATA_EFLAG_* flags
1787 *	@err_mask: err_mask of the error
1788 *
1789 *	Record error and examine error history to determine whether
1790 *	adjusting transmission speed is necessary.  It also sets
1791 *	transmission limits appropriately if such adjustment is
1792 *	necessary.
1793 *
1794 *	LOCKING:
1795 *	Kernel thread context (may sleep).
1796 *
1797 *	RETURNS:
1798 *	Determined recovery action.
1799 */
1800static unsigned int ata_eh_speed_down(struct ata_device *dev,
1801				unsigned int eflags, unsigned int err_mask)
1802{
1803	struct ata_link *link = ata_dev_phys_link(dev);
1804	int xfer_ok = 0;
1805	unsigned int verdict;
1806	unsigned int action = 0;
1807
1808	/* don't bother if Cat-0 error */
1809	if (ata_eh_categorize_error(eflags, err_mask, &xfer_ok) == 0)
1810		return 0;
1811
1812	/* record error and determine whether speed down is necessary */
1813	ata_ering_record(&dev->ering, eflags, err_mask);
1814	verdict = ata_eh_speed_down_verdict(dev);
1815
1816	/* turn off NCQ? */
1817	if ((verdict & ATA_EH_SPDN_NCQ_OFF) &&
1818	    (dev->flags & (ATA_DFLAG_PIO | ATA_DFLAG_NCQ |
1819			   ATA_DFLAG_NCQ_OFF)) == ATA_DFLAG_NCQ) {
1820		dev->flags |= ATA_DFLAG_NCQ_OFF;
1821		ata_dev_warn(dev, "NCQ disabled due to excessive errors\n");
1822		goto done;
1823	}
1824
1825	/* speed down? */
1826	if (verdict & ATA_EH_SPDN_SPEED_DOWN) {
1827		/* speed down SATA link speed if possible */
1828		if (sata_down_spd_limit(link, 0) == 0) {
1829			action |= ATA_EH_RESET;
1830			goto done;
1831		}
1832
1833		/* lower transfer mode */
1834		if (dev->spdn_cnt < 2) {
1835			static const int dma_dnxfer_sel[] =
1836				{ ATA_DNXFER_DMA, ATA_DNXFER_40C };
1837			static const int pio_dnxfer_sel[] =
1838				{ ATA_DNXFER_PIO, ATA_DNXFER_FORCE_PIO0 };
1839			int sel;
1840
1841			if (dev->xfer_shift != ATA_SHIFT_PIO)
1842				sel = dma_dnxfer_sel[dev->spdn_cnt];
1843			else
1844				sel = pio_dnxfer_sel[dev->spdn_cnt];
1845
1846			dev->spdn_cnt++;
1847
1848			if (ata_down_xfermask_limit(dev, sel) == 0) {
1849				action |= ATA_EH_RESET;
1850				goto done;
1851			}
1852		}
1853	}
1854
1855	/* Fall back to PIO?  Slowing down to PIO is meaningless for
1856	 * SATA ATA devices.  Consider it only for PATA and SATAPI.
1857	 */
1858	if ((verdict & ATA_EH_SPDN_FALLBACK_TO_PIO) && (dev->spdn_cnt >= 2) &&
1859	    (link->ap->cbl != ATA_CBL_SATA || dev->class == ATA_DEV_ATAPI) &&
1860	    (dev->xfer_shift != ATA_SHIFT_PIO)) {
1861		if (ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO) == 0) {
1862			dev->spdn_cnt = 0;
1863			action |= ATA_EH_RESET;
1864			goto done;
1865		}
1866	}
1867
1868	return 0;
1869 done:
1870	/* device has been slowed down, blow error history */
1871	if (!(verdict & ATA_EH_SPDN_KEEP_ERRORS))
1872		ata_ering_clear(&dev->ering);
1873	return action;
1874}
1875
1876/**
1877 *	ata_eh_worth_retry - analyze error and decide whether to retry
1878 *	@qc: qc to possibly retry
1879 *
1880 *	Look at the cause of the error and decide if a retry
1881 * 	might be useful or not.  We don't want to retry media errors
1882 *	because the drive itself has probably already taken 10-30 seconds
1883 *	doing its own internal retries before reporting the failure.
1884 */
1885static inline int ata_eh_worth_retry(struct ata_queued_cmd *qc)
1886{
1887	if (qc->err_mask & AC_ERR_MEDIA)
1888		return 0;	/* don't retry media errors */
1889	if (qc->flags & ATA_QCFLAG_IO)
1890		return 1;	/* otherwise retry anything from fs stack */
1891	if (qc->err_mask & AC_ERR_INVALID)
1892		return 0;	/* don't retry these */
1893	return qc->err_mask != AC_ERR_DEV;  /* retry if not dev error */
1894}
1895
1896/**
1897 *      ata_eh_quiet - check if we need to be quiet about a command error
1898 *      @qc: qc to check
1899 *
1900 *      Look at the qc flags anbd its scsi command request flags to determine
1901 *      if we need to be quiet about the command failure.
1902 */
1903static inline bool ata_eh_quiet(struct ata_queued_cmd *qc)
1904{
1905	if (qc->scsicmd && scsi_cmd_to_rq(qc->scsicmd)->rq_flags & RQF_QUIET)
1906		qc->flags |= ATA_QCFLAG_QUIET;
1907	return qc->flags & ATA_QCFLAG_QUIET;
1908}
1909
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1910/**
1911 *	ata_eh_link_autopsy - analyze error and determine recovery action
1912 *	@link: host link to perform autopsy on
1913 *
1914 *	Analyze why @link failed and determine which recovery actions
1915 *	are needed.  This function also sets more detailed AC_ERR_*
1916 *	values and fills sense data for ATAPI CHECK SENSE.
1917 *
1918 *	LOCKING:
1919 *	Kernel thread context (may sleep).
1920 */
1921static void ata_eh_link_autopsy(struct ata_link *link)
1922{
1923	struct ata_port *ap = link->ap;
1924	struct ata_eh_context *ehc = &link->eh_context;
1925	struct ata_queued_cmd *qc;
1926	struct ata_device *dev;
1927	unsigned int all_err_mask = 0, eflags = 0;
1928	int tag, nr_failed = 0, nr_quiet = 0;
1929	u32 serror;
1930	int rc;
1931
1932	if (ehc->i.flags & ATA_EHI_NO_AUTOPSY)
1933		return;
1934
1935	/* obtain and analyze SError */
1936	rc = sata_scr_read(link, SCR_ERROR, &serror);
1937	if (rc == 0) {
1938		ehc->i.serror |= serror;
1939		ata_eh_analyze_serror(link);
1940	} else if (rc != -EOPNOTSUPP) {
1941		/* SError read failed, force reset and probing */
1942		ehc->i.probe_mask |= ATA_ALL_DEVICES;
1943		ehc->i.action |= ATA_EH_RESET;
1944		ehc->i.err_mask |= AC_ERR_OTHER;
1945	}
1946
1947	/* analyze NCQ failure */
1948	ata_eh_analyze_ncq_error(link);
1949
 
 
 
 
 
 
 
 
1950	/* any real error trumps AC_ERR_OTHER */
1951	if (ehc->i.err_mask & ~AC_ERR_OTHER)
1952		ehc->i.err_mask &= ~AC_ERR_OTHER;
1953
1954	all_err_mask |= ehc->i.err_mask;
1955
1956	ata_qc_for_each_raw(ap, qc, tag) {
1957		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
1958		    qc->flags & ATA_QCFLAG_RETRY ||
 
1959		    ata_dev_phys_link(qc->dev) != link)
1960			continue;
1961
1962		/* inherit upper level err_mask */
1963		qc->err_mask |= ehc->i.err_mask;
1964
1965		/* analyze TF */
1966		ehc->i.action |= ata_eh_analyze_tf(qc);
1967
1968		/* DEV errors are probably spurious in case of ATA_BUS error */
1969		if (qc->err_mask & AC_ERR_ATA_BUS)
1970			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_MEDIA |
1971					  AC_ERR_INVALID);
1972
1973		/* any real error trumps unknown error */
1974		if (qc->err_mask & ~AC_ERR_OTHER)
1975			qc->err_mask &= ~AC_ERR_OTHER;
1976
1977		/*
1978		 * SENSE_VALID trumps dev/unknown error and revalidation. Upper
1979		 * layers will determine whether the command is worth retrying
1980		 * based on the sense data and device class/type. Otherwise,
1981		 * determine directly if the command is worth retrying using its
1982		 * error mask and flags.
1983		 */
1984		if (qc->flags & ATA_QCFLAG_SENSE_VALID)
1985			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_OTHER);
1986		else if (ata_eh_worth_retry(qc))
1987			qc->flags |= ATA_QCFLAG_RETRY;
1988
1989		/* accumulate error info */
1990		ehc->i.dev = qc->dev;
1991		all_err_mask |= qc->err_mask;
1992		if (qc->flags & ATA_QCFLAG_IO)
1993			eflags |= ATA_EFLAG_IS_IO;
1994		trace_ata_eh_link_autopsy_qc(qc);
1995
1996		/* Count quiet errors */
1997		if (ata_eh_quiet(qc))
1998			nr_quiet++;
1999		nr_failed++;
2000	}
2001
2002	/* If all failed commands requested silence, then be quiet */
2003	if (nr_quiet == nr_failed)
2004		ehc->i.flags |= ATA_EHI_QUIET;
2005
2006	/* enforce default EH actions */
2007	if (ata_port_is_frozen(ap) ||
2008	    all_err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT))
2009		ehc->i.action |= ATA_EH_RESET;
2010	else if (((eflags & ATA_EFLAG_IS_IO) && all_err_mask) ||
2011		 (!(eflags & ATA_EFLAG_IS_IO) && (all_err_mask & ~AC_ERR_DEV)))
2012		ehc->i.action |= ATA_EH_REVALIDATE;
2013
2014	/* If we have offending qcs and the associated failed device,
2015	 * perform per-dev EH action only on the offending device.
2016	 */
2017	if (ehc->i.dev) {
2018		ehc->i.dev_action[ehc->i.dev->devno] |=
2019			ehc->i.action & ATA_EH_PERDEV_MASK;
2020		ehc->i.action &= ~ATA_EH_PERDEV_MASK;
2021	}
2022
2023	/* propagate timeout to host link */
2024	if ((all_err_mask & AC_ERR_TIMEOUT) && !ata_is_host_link(link))
2025		ap->link.eh_context.i.err_mask |= AC_ERR_TIMEOUT;
2026
2027	/* record error and consider speeding down */
2028	dev = ehc->i.dev;
2029	if (!dev && ((ata_link_max_devices(link) == 1 &&
2030		      ata_dev_enabled(link->device))))
2031	    dev = link->device;
2032
2033	if (dev) {
2034		if (dev->flags & ATA_DFLAG_DUBIOUS_XFER)
2035			eflags |= ATA_EFLAG_DUBIOUS_XFER;
2036		ehc->i.action |= ata_eh_speed_down(dev, eflags, all_err_mask);
2037		trace_ata_eh_link_autopsy(dev, ehc->i.action, all_err_mask);
2038	}
2039}
2040
2041/**
2042 *	ata_eh_autopsy - analyze error and determine recovery action
2043 *	@ap: host port to perform autopsy on
2044 *
2045 *	Analyze all links of @ap and determine why they failed and
2046 *	which recovery actions are needed.
2047 *
2048 *	LOCKING:
2049 *	Kernel thread context (may sleep).
2050 */
2051void ata_eh_autopsy(struct ata_port *ap)
2052{
2053	struct ata_link *link;
2054
2055	ata_for_each_link(link, ap, EDGE)
2056		ata_eh_link_autopsy(link);
2057
2058	/* Handle the frigging slave link.  Autopsy is done similarly
2059	 * but actions and flags are transferred over to the master
2060	 * link and handled from there.
2061	 */
2062	if (ap->slave_link) {
2063		struct ata_eh_context *mehc = &ap->link.eh_context;
2064		struct ata_eh_context *sehc = &ap->slave_link->eh_context;
2065
2066		/* transfer control flags from master to slave */
2067		sehc->i.flags |= mehc->i.flags & ATA_EHI_TO_SLAVE_MASK;
2068
2069		/* perform autopsy on the slave link */
2070		ata_eh_link_autopsy(ap->slave_link);
2071
2072		/* transfer actions from slave to master and clear slave */
2073		ata_eh_about_to_do(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2074		mehc->i.action		|= sehc->i.action;
2075		mehc->i.dev_action[1]	|= sehc->i.dev_action[1];
2076		mehc->i.flags		|= sehc->i.flags;
2077		ata_eh_done(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2078	}
2079
2080	/* Autopsy of fanout ports can affect host link autopsy.
2081	 * Perform host link autopsy last.
2082	 */
2083	if (sata_pmp_attached(ap))
2084		ata_eh_link_autopsy(&ap->link);
2085}
2086
2087/**
2088 *	ata_get_cmd_name - get name for ATA command
2089 *	@command: ATA command code to get name for
2090 *
2091 *	Return a textual name of the given command or "unknown"
2092 *
2093 *	LOCKING:
2094 *	None
2095 */
2096const char *ata_get_cmd_name(u8 command)
2097{
2098#ifdef CONFIG_ATA_VERBOSE_ERROR
2099	static const struct
2100	{
2101		u8 command;
2102		const char *text;
2103	} cmd_descr[] = {
2104		{ ATA_CMD_DEV_RESET,		"DEVICE RESET" },
2105		{ ATA_CMD_CHK_POWER,		"CHECK POWER MODE" },
2106		{ ATA_CMD_STANDBY,		"STANDBY" },
2107		{ ATA_CMD_IDLE,			"IDLE" },
2108		{ ATA_CMD_EDD,			"EXECUTE DEVICE DIAGNOSTIC" },
2109		{ ATA_CMD_DOWNLOAD_MICRO,	"DOWNLOAD MICROCODE" },
2110		{ ATA_CMD_DOWNLOAD_MICRO_DMA,	"DOWNLOAD MICROCODE DMA" },
2111		{ ATA_CMD_NOP,			"NOP" },
2112		{ ATA_CMD_FLUSH,		"FLUSH CACHE" },
2113		{ ATA_CMD_FLUSH_EXT,		"FLUSH CACHE EXT" },
2114		{ ATA_CMD_ID_ATA,		"IDENTIFY DEVICE" },
2115		{ ATA_CMD_ID_ATAPI,		"IDENTIFY PACKET DEVICE" },
2116		{ ATA_CMD_SERVICE,		"SERVICE" },
2117		{ ATA_CMD_READ,			"READ DMA" },
2118		{ ATA_CMD_READ_EXT,		"READ DMA EXT" },
2119		{ ATA_CMD_READ_QUEUED,		"READ DMA QUEUED" },
2120		{ ATA_CMD_READ_STREAM_EXT,	"READ STREAM EXT" },
2121		{ ATA_CMD_READ_STREAM_DMA_EXT,  "READ STREAM DMA EXT" },
2122		{ ATA_CMD_WRITE,		"WRITE DMA" },
2123		{ ATA_CMD_WRITE_EXT,		"WRITE DMA EXT" },
2124		{ ATA_CMD_WRITE_QUEUED,		"WRITE DMA QUEUED EXT" },
2125		{ ATA_CMD_WRITE_STREAM_EXT,	"WRITE STREAM EXT" },
2126		{ ATA_CMD_WRITE_STREAM_DMA_EXT, "WRITE STREAM DMA EXT" },
2127		{ ATA_CMD_WRITE_FUA_EXT,	"WRITE DMA FUA EXT" },
2128		{ ATA_CMD_WRITE_QUEUED_FUA_EXT, "WRITE DMA QUEUED FUA EXT" },
2129		{ ATA_CMD_FPDMA_READ,		"READ FPDMA QUEUED" },
2130		{ ATA_CMD_FPDMA_WRITE,		"WRITE FPDMA QUEUED" },
2131		{ ATA_CMD_NCQ_NON_DATA,		"NCQ NON-DATA" },
2132		{ ATA_CMD_FPDMA_SEND,		"SEND FPDMA QUEUED" },
2133		{ ATA_CMD_FPDMA_RECV,		"RECEIVE FPDMA QUEUED" },
2134		{ ATA_CMD_PIO_READ,		"READ SECTOR(S)" },
2135		{ ATA_CMD_PIO_READ_EXT,		"READ SECTOR(S) EXT" },
2136		{ ATA_CMD_PIO_WRITE,		"WRITE SECTOR(S)" },
2137		{ ATA_CMD_PIO_WRITE_EXT,	"WRITE SECTOR(S) EXT" },
2138		{ ATA_CMD_READ_MULTI,		"READ MULTIPLE" },
2139		{ ATA_CMD_READ_MULTI_EXT,	"READ MULTIPLE EXT" },
2140		{ ATA_CMD_WRITE_MULTI,		"WRITE MULTIPLE" },
2141		{ ATA_CMD_WRITE_MULTI_EXT,	"WRITE MULTIPLE EXT" },
2142		{ ATA_CMD_WRITE_MULTI_FUA_EXT,	"WRITE MULTIPLE FUA EXT" },
2143		{ ATA_CMD_SET_FEATURES,		"SET FEATURES" },
2144		{ ATA_CMD_SET_MULTI,		"SET MULTIPLE MODE" },
2145		{ ATA_CMD_VERIFY,		"READ VERIFY SECTOR(S)" },
2146		{ ATA_CMD_VERIFY_EXT,		"READ VERIFY SECTOR(S) EXT" },
2147		{ ATA_CMD_WRITE_UNCORR_EXT,	"WRITE UNCORRECTABLE EXT" },
2148		{ ATA_CMD_STANDBYNOW1,		"STANDBY IMMEDIATE" },
2149		{ ATA_CMD_IDLEIMMEDIATE,	"IDLE IMMEDIATE" },
2150		{ ATA_CMD_SLEEP,		"SLEEP" },
2151		{ ATA_CMD_INIT_DEV_PARAMS,	"INITIALIZE DEVICE PARAMETERS" },
2152		{ ATA_CMD_READ_NATIVE_MAX,	"READ NATIVE MAX ADDRESS" },
2153		{ ATA_CMD_READ_NATIVE_MAX_EXT,	"READ NATIVE MAX ADDRESS EXT" },
2154		{ ATA_CMD_SET_MAX,		"SET MAX ADDRESS" },
2155		{ ATA_CMD_SET_MAX_EXT,		"SET MAX ADDRESS EXT" },
2156		{ ATA_CMD_READ_LOG_EXT,		"READ LOG EXT" },
2157		{ ATA_CMD_WRITE_LOG_EXT,	"WRITE LOG EXT" },
2158		{ ATA_CMD_READ_LOG_DMA_EXT,	"READ LOG DMA EXT" },
2159		{ ATA_CMD_WRITE_LOG_DMA_EXT,	"WRITE LOG DMA EXT" },
2160		{ ATA_CMD_TRUSTED_NONDATA,	"TRUSTED NON-DATA" },
2161		{ ATA_CMD_TRUSTED_RCV,		"TRUSTED RECEIVE" },
2162		{ ATA_CMD_TRUSTED_RCV_DMA,	"TRUSTED RECEIVE DMA" },
2163		{ ATA_CMD_TRUSTED_SND,		"TRUSTED SEND" },
2164		{ ATA_CMD_TRUSTED_SND_DMA,	"TRUSTED SEND DMA" },
2165		{ ATA_CMD_PMP_READ,		"READ BUFFER" },
2166		{ ATA_CMD_PMP_READ_DMA,		"READ BUFFER DMA" },
2167		{ ATA_CMD_PMP_WRITE,		"WRITE BUFFER" },
2168		{ ATA_CMD_PMP_WRITE_DMA,	"WRITE BUFFER DMA" },
2169		{ ATA_CMD_CONF_OVERLAY,		"DEVICE CONFIGURATION OVERLAY" },
2170		{ ATA_CMD_SEC_SET_PASS,		"SECURITY SET PASSWORD" },
2171		{ ATA_CMD_SEC_UNLOCK,		"SECURITY UNLOCK" },
2172		{ ATA_CMD_SEC_ERASE_PREP,	"SECURITY ERASE PREPARE" },
2173		{ ATA_CMD_SEC_ERASE_UNIT,	"SECURITY ERASE UNIT" },
2174		{ ATA_CMD_SEC_FREEZE_LOCK,	"SECURITY FREEZE LOCK" },
2175		{ ATA_CMD_SEC_DISABLE_PASS,	"SECURITY DISABLE PASSWORD" },
2176		{ ATA_CMD_CONFIG_STREAM,	"CONFIGURE STREAM" },
2177		{ ATA_CMD_SMART,		"SMART" },
2178		{ ATA_CMD_MEDIA_LOCK,		"DOOR LOCK" },
2179		{ ATA_CMD_MEDIA_UNLOCK,		"DOOR UNLOCK" },
2180		{ ATA_CMD_DSM,			"DATA SET MANAGEMENT" },
2181		{ ATA_CMD_CHK_MED_CRD_TYP,	"CHECK MEDIA CARD TYPE" },
2182		{ ATA_CMD_CFA_REQ_EXT_ERR,	"CFA REQUEST EXTENDED ERROR" },
2183		{ ATA_CMD_CFA_WRITE_NE,		"CFA WRITE SECTORS WITHOUT ERASE" },
2184		{ ATA_CMD_CFA_TRANS_SECT,	"CFA TRANSLATE SECTOR" },
2185		{ ATA_CMD_CFA_ERASE,		"CFA ERASE SECTORS" },
2186		{ ATA_CMD_CFA_WRITE_MULT_NE,	"CFA WRITE MULTIPLE WITHOUT ERASE" },
2187		{ ATA_CMD_REQ_SENSE_DATA,	"REQUEST SENSE DATA EXT" },
2188		{ ATA_CMD_SANITIZE_DEVICE,	"SANITIZE DEVICE" },
2189		{ ATA_CMD_ZAC_MGMT_IN,		"ZAC MANAGEMENT IN" },
2190		{ ATA_CMD_ZAC_MGMT_OUT,		"ZAC MANAGEMENT OUT" },
2191		{ ATA_CMD_READ_LONG,		"READ LONG (with retries)" },
2192		{ ATA_CMD_READ_LONG_ONCE,	"READ LONG (without retries)" },
2193		{ ATA_CMD_WRITE_LONG,		"WRITE LONG (with retries)" },
2194		{ ATA_CMD_WRITE_LONG_ONCE,	"WRITE LONG (without retries)" },
2195		{ ATA_CMD_RESTORE,		"RECALIBRATE" },
2196		{ 0,				NULL } /* terminate list */
2197	};
2198
2199	unsigned int i;
2200	for (i = 0; cmd_descr[i].text; i++)
2201		if (cmd_descr[i].command == command)
2202			return cmd_descr[i].text;
2203#endif
2204
2205	return "unknown";
2206}
2207EXPORT_SYMBOL_GPL(ata_get_cmd_name);
2208
2209/**
2210 *	ata_eh_link_report - report error handling to user
2211 *	@link: ATA link EH is going on
2212 *
2213 *	Report EH to user.
2214 *
2215 *	LOCKING:
2216 *	None.
2217 */
2218static void ata_eh_link_report(struct ata_link *link)
2219{
2220	struct ata_port *ap = link->ap;
2221	struct ata_eh_context *ehc = &link->eh_context;
2222	struct ata_queued_cmd *qc;
2223	const char *frozen, *desc;
2224	char tries_buf[6] = "";
2225	int tag, nr_failed = 0;
2226
2227	if (ehc->i.flags & ATA_EHI_QUIET)
2228		return;
2229
2230	desc = NULL;
2231	if (ehc->i.desc[0] != '\0')
2232		desc = ehc->i.desc;
2233
2234	ata_qc_for_each_raw(ap, qc, tag) {
2235		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2236		    ata_dev_phys_link(qc->dev) != link ||
2237		    ((qc->flags & ATA_QCFLAG_QUIET) &&
2238		     qc->err_mask == AC_ERR_DEV))
2239			continue;
2240		if (qc->flags & ATA_QCFLAG_SENSE_VALID && !qc->err_mask)
2241			continue;
2242
2243		nr_failed++;
2244	}
2245
2246	if (!nr_failed && !ehc->i.err_mask)
2247		return;
2248
2249	frozen = "";
2250	if (ata_port_is_frozen(ap))
2251		frozen = " frozen";
2252
2253	if (ap->eh_tries < ATA_EH_MAX_TRIES)
2254		snprintf(tries_buf, sizeof(tries_buf), " t%d",
2255			 ap->eh_tries);
2256
2257	if (ehc->i.dev) {
2258		ata_dev_err(ehc->i.dev, "exception Emask 0x%x "
2259			    "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2260			    ehc->i.err_mask, link->sactive, ehc->i.serror,
2261			    ehc->i.action, frozen, tries_buf);
2262		if (desc)
2263			ata_dev_err(ehc->i.dev, "%s\n", desc);
2264	} else {
2265		ata_link_err(link, "exception Emask 0x%x "
2266			     "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2267			     ehc->i.err_mask, link->sactive, ehc->i.serror,
2268			     ehc->i.action, frozen, tries_buf);
2269		if (desc)
2270			ata_link_err(link, "%s\n", desc);
2271	}
2272
2273#ifdef CONFIG_ATA_VERBOSE_ERROR
2274	if (ehc->i.serror)
2275		ata_link_err(link,
2276		  "SError: { %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s}\n",
2277		  ehc->i.serror & SERR_DATA_RECOVERED ? "RecovData " : "",
2278		  ehc->i.serror & SERR_COMM_RECOVERED ? "RecovComm " : "",
2279		  ehc->i.serror & SERR_DATA ? "UnrecovData " : "",
2280		  ehc->i.serror & SERR_PERSISTENT ? "Persist " : "",
2281		  ehc->i.serror & SERR_PROTOCOL ? "Proto " : "",
2282		  ehc->i.serror & SERR_INTERNAL ? "HostInt " : "",
2283		  ehc->i.serror & SERR_PHYRDY_CHG ? "PHYRdyChg " : "",
2284		  ehc->i.serror & SERR_PHY_INT_ERR ? "PHYInt " : "",
2285		  ehc->i.serror & SERR_COMM_WAKE ? "CommWake " : "",
2286		  ehc->i.serror & SERR_10B_8B_ERR ? "10B8B " : "",
2287		  ehc->i.serror & SERR_DISPARITY ? "Dispar " : "",
2288		  ehc->i.serror & SERR_CRC ? "BadCRC " : "",
2289		  ehc->i.serror & SERR_HANDSHAKE ? "Handshk " : "",
2290		  ehc->i.serror & SERR_LINK_SEQ_ERR ? "LinkSeq " : "",
2291		  ehc->i.serror & SERR_TRANS_ST_ERROR ? "TrStaTrns " : "",
2292		  ehc->i.serror & SERR_UNRECOG_FIS ? "UnrecFIS " : "",
2293		  ehc->i.serror & SERR_DEV_XCHG ? "DevExch " : "");
2294#endif
2295
2296	ata_qc_for_each_raw(ap, qc, tag) {
2297		struct ata_taskfile *cmd = &qc->tf, *res = &qc->result_tf;
2298		char data_buf[20] = "";
2299		char cdb_buf[70] = "";
2300
2301		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2302		    ata_dev_phys_link(qc->dev) != link || !qc->err_mask)
2303			continue;
2304
2305		if (qc->dma_dir != DMA_NONE) {
2306			static const char *dma_str[] = {
2307				[DMA_BIDIRECTIONAL]	= "bidi",
2308				[DMA_TO_DEVICE]		= "out",
2309				[DMA_FROM_DEVICE]	= "in",
2310			};
2311			const char *prot_str = NULL;
2312
2313			switch (qc->tf.protocol) {
2314			case ATA_PROT_UNKNOWN:
2315				prot_str = "unknown";
2316				break;
2317			case ATA_PROT_NODATA:
2318				prot_str = "nodata";
2319				break;
2320			case ATA_PROT_PIO:
2321				prot_str = "pio";
2322				break;
2323			case ATA_PROT_DMA:
2324				prot_str = "dma";
2325				break;
2326			case ATA_PROT_NCQ:
2327				prot_str = "ncq dma";
2328				break;
2329			case ATA_PROT_NCQ_NODATA:
2330				prot_str = "ncq nodata";
2331				break;
2332			case ATAPI_PROT_NODATA:
2333				prot_str = "nodata";
2334				break;
2335			case ATAPI_PROT_PIO:
2336				prot_str = "pio";
2337				break;
2338			case ATAPI_PROT_DMA:
2339				prot_str = "dma";
2340				break;
2341			}
2342			snprintf(data_buf, sizeof(data_buf), " %s %u %s",
2343				 prot_str, qc->nbytes, dma_str[qc->dma_dir]);
2344		}
2345
2346		if (ata_is_atapi(qc->tf.protocol)) {
2347			const u8 *cdb = qc->cdb;
2348			size_t cdb_len = qc->dev->cdb_len;
2349
2350			if (qc->scsicmd) {
2351				cdb = qc->scsicmd->cmnd;
2352				cdb_len = qc->scsicmd->cmd_len;
2353			}
2354			__scsi_format_command(cdb_buf, sizeof(cdb_buf),
2355					      cdb, cdb_len);
2356		} else
2357			ata_dev_err(qc->dev, "failed command: %s\n",
2358				    ata_get_cmd_name(cmd->command));
2359
2360		ata_dev_err(qc->dev,
2361			"cmd %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2362			"tag %d%s\n         %s"
2363			"res %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2364			"Emask 0x%x (%s)%s\n",
2365			cmd->command, cmd->feature, cmd->nsect,
2366			cmd->lbal, cmd->lbam, cmd->lbah,
2367			cmd->hob_feature, cmd->hob_nsect,
2368			cmd->hob_lbal, cmd->hob_lbam, cmd->hob_lbah,
2369			cmd->device, qc->tag, data_buf, cdb_buf,
2370			res->status, res->error, res->nsect,
2371			res->lbal, res->lbam, res->lbah,
2372			res->hob_feature, res->hob_nsect,
2373			res->hob_lbal, res->hob_lbam, res->hob_lbah,
2374			res->device, qc->err_mask, ata_err_string(qc->err_mask),
2375			qc->err_mask & AC_ERR_NCQ ? " <F>" : "");
2376
2377#ifdef CONFIG_ATA_VERBOSE_ERROR
2378		if (res->status & (ATA_BUSY | ATA_DRDY | ATA_DF | ATA_DRQ |
2379				   ATA_SENSE | ATA_ERR)) {
2380			if (res->status & ATA_BUSY)
2381				ata_dev_err(qc->dev, "status: { Busy }\n");
2382			else
2383				ata_dev_err(qc->dev, "status: { %s%s%s%s%s}\n",
2384				  res->status & ATA_DRDY ? "DRDY " : "",
2385				  res->status & ATA_DF ? "DF " : "",
2386				  res->status & ATA_DRQ ? "DRQ " : "",
2387				  res->status & ATA_SENSE ? "SENSE " : "",
2388				  res->status & ATA_ERR ? "ERR " : "");
2389		}
2390
2391		if (cmd->command != ATA_CMD_PACKET &&
2392		    (res->error & (ATA_ICRC | ATA_UNC | ATA_AMNF | ATA_IDNF |
2393				   ATA_ABORTED)))
2394			ata_dev_err(qc->dev, "error: { %s%s%s%s%s}\n",
2395				    res->error & ATA_ICRC ? "ICRC " : "",
2396				    res->error & ATA_UNC ? "UNC " : "",
2397				    res->error & ATA_AMNF ? "AMNF " : "",
2398				    res->error & ATA_IDNF ? "IDNF " : "",
2399				    res->error & ATA_ABORTED ? "ABRT " : "");
2400#endif
2401	}
2402}
2403
2404/**
2405 *	ata_eh_report - report error handling to user
2406 *	@ap: ATA port to report EH about
2407 *
2408 *	Report EH to user.
2409 *
2410 *	LOCKING:
2411 *	None.
2412 */
2413void ata_eh_report(struct ata_port *ap)
2414{
2415	struct ata_link *link;
2416
2417	ata_for_each_link(link, ap, HOST_FIRST)
2418		ata_eh_link_report(link);
2419}
2420
2421static int ata_do_reset(struct ata_link *link, ata_reset_fn_t reset,
2422			unsigned int *classes, unsigned long deadline,
2423			bool clear_classes)
2424{
2425	struct ata_device *dev;
2426
2427	if (clear_classes)
2428		ata_for_each_dev(dev, link, ALL)
2429			classes[dev->devno] = ATA_DEV_UNKNOWN;
2430
2431	return reset(link, classes, deadline);
2432}
2433
2434static int ata_eh_followup_srst_needed(struct ata_link *link, int rc)
2435{
2436	if ((link->flags & ATA_LFLAG_NO_SRST) || ata_link_offline(link))
2437		return 0;
2438	if (rc == -EAGAIN)
2439		return 1;
2440	if (sata_pmp_supported(link->ap) && ata_is_host_link(link))
2441		return 1;
2442	return 0;
2443}
2444
2445int ata_eh_reset(struct ata_link *link, int classify,
2446		 ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
2447		 ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
2448{
2449	struct ata_port *ap = link->ap;
2450	struct ata_link *slave = ap->slave_link;
2451	struct ata_eh_context *ehc = &link->eh_context;
2452	struct ata_eh_context *sehc = slave ? &slave->eh_context : NULL;
2453	unsigned int *classes = ehc->classes;
2454	unsigned int lflags = link->flags;
2455	int verbose = !(ehc->i.flags & ATA_EHI_QUIET);
2456	int max_tries = 0, try = 0;
2457	struct ata_link *failed_link;
2458	struct ata_device *dev;
2459	unsigned long deadline, now;
2460	ata_reset_fn_t reset;
2461	unsigned long flags;
2462	u32 sstatus;
2463	int nr_unknown, rc;
2464
2465	/*
2466	 * Prepare to reset
2467	 */
2468	while (ata_eh_reset_timeouts[max_tries] != ULONG_MAX)
2469		max_tries++;
2470	if (link->flags & ATA_LFLAG_RST_ONCE)
2471		max_tries = 1;
2472	if (link->flags & ATA_LFLAG_NO_HRST)
2473		hardreset = NULL;
2474	if (link->flags & ATA_LFLAG_NO_SRST)
2475		softreset = NULL;
2476
2477	/* make sure each reset attempt is at least COOL_DOWN apart */
2478	if (ehc->i.flags & ATA_EHI_DID_RESET) {
2479		now = jiffies;
2480		WARN_ON(time_after(ehc->last_reset, now));
2481		deadline = ata_deadline(ehc->last_reset,
2482					ATA_EH_RESET_COOL_DOWN);
2483		if (time_before(now, deadline))
2484			schedule_timeout_uninterruptible(deadline - now);
2485	}
2486
2487	spin_lock_irqsave(ap->lock, flags);
2488	ap->pflags |= ATA_PFLAG_RESETTING;
2489	spin_unlock_irqrestore(ap->lock, flags);
2490
2491	ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2492
2493	ata_for_each_dev(dev, link, ALL) {
2494		/* If we issue an SRST then an ATA drive (not ATAPI)
2495		 * may change configuration and be in PIO0 timing. If
2496		 * we do a hard reset (or are coming from power on)
2497		 * this is true for ATA or ATAPI. Until we've set a
2498		 * suitable controller mode we should not touch the
2499		 * bus as we may be talking too fast.
2500		 */
2501		dev->pio_mode = XFER_PIO_0;
2502		dev->dma_mode = 0xff;
2503
2504		/* If the controller has a pio mode setup function
2505		 * then use it to set the chipset to rights. Don't
2506		 * touch the DMA setup as that will be dealt with when
2507		 * configuring devices.
2508		 */
2509		if (ap->ops->set_piomode)
2510			ap->ops->set_piomode(ap, dev);
2511	}
2512
2513	/* prefer hardreset */
2514	reset = NULL;
2515	ehc->i.action &= ~ATA_EH_RESET;
2516	if (hardreset) {
2517		reset = hardreset;
2518		ehc->i.action |= ATA_EH_HARDRESET;
2519	} else if (softreset) {
2520		reset = softreset;
2521		ehc->i.action |= ATA_EH_SOFTRESET;
2522	}
2523
2524	if (prereset) {
2525		unsigned long deadline = ata_deadline(jiffies,
2526						      ATA_EH_PRERESET_TIMEOUT);
2527
2528		if (slave) {
2529			sehc->i.action &= ~ATA_EH_RESET;
2530			sehc->i.action |= ehc->i.action;
2531		}
2532
2533		rc = prereset(link, deadline);
2534
2535		/* If present, do prereset on slave link too.  Reset
2536		 * is skipped iff both master and slave links report
2537		 * -ENOENT or clear ATA_EH_RESET.
2538		 */
2539		if (slave && (rc == 0 || rc == -ENOENT)) {
2540			int tmp;
2541
2542			tmp = prereset(slave, deadline);
2543			if (tmp != -ENOENT)
2544				rc = tmp;
2545
2546			ehc->i.action |= sehc->i.action;
2547		}
2548
2549		if (rc) {
2550			if (rc == -ENOENT) {
2551				ata_link_dbg(link, "port disabled--ignoring\n");
2552				ehc->i.action &= ~ATA_EH_RESET;
2553
2554				ata_for_each_dev(dev, link, ALL)
2555					classes[dev->devno] = ATA_DEV_NONE;
2556
2557				rc = 0;
2558			} else
2559				ata_link_err(link,
2560					     "prereset failed (errno=%d)\n",
2561					     rc);
2562			goto out;
2563		}
2564
2565		/* prereset() might have cleared ATA_EH_RESET.  If so,
2566		 * bang classes, thaw and return.
2567		 */
2568		if (reset && !(ehc->i.action & ATA_EH_RESET)) {
2569			ata_for_each_dev(dev, link, ALL)
2570				classes[dev->devno] = ATA_DEV_NONE;
2571			if (ata_port_is_frozen(ap) && ata_is_host_link(link))
2572				ata_eh_thaw_port(ap);
2573			rc = 0;
2574			goto out;
2575		}
2576	}
2577
2578 retry:
2579	/*
2580	 * Perform reset
2581	 */
2582	if (ata_is_host_link(link))
2583		ata_eh_freeze_port(ap);
2584
2585	deadline = ata_deadline(jiffies, ata_eh_reset_timeouts[try++]);
2586
2587	if (reset) {
2588		if (verbose)
2589			ata_link_info(link, "%s resetting link\n",
2590				      reset == softreset ? "soft" : "hard");
2591
2592		/* mark that this EH session started with reset */
2593		ehc->last_reset = jiffies;
2594		if (reset == hardreset) {
2595			ehc->i.flags |= ATA_EHI_DID_HARDRESET;
2596			trace_ata_link_hardreset_begin(link, classes, deadline);
2597		} else {
2598			ehc->i.flags |= ATA_EHI_DID_SOFTRESET;
2599			trace_ata_link_softreset_begin(link, classes, deadline);
2600		}
2601
2602		rc = ata_do_reset(link, reset, classes, deadline, true);
2603		if (reset == hardreset)
2604			trace_ata_link_hardreset_end(link, classes, rc);
2605		else
2606			trace_ata_link_softreset_end(link, classes, rc);
2607		if (rc && rc != -EAGAIN) {
2608			failed_link = link;
2609			goto fail;
2610		}
2611
2612		/* hardreset slave link if existent */
2613		if (slave && reset == hardreset) {
2614			int tmp;
2615
2616			if (verbose)
2617				ata_link_info(slave, "hard resetting link\n");
2618
2619			ata_eh_about_to_do(slave, NULL, ATA_EH_RESET);
2620			trace_ata_slave_hardreset_begin(slave, classes,
2621							deadline);
2622			tmp = ata_do_reset(slave, reset, classes, deadline,
2623					   false);
2624			trace_ata_slave_hardreset_end(slave, classes, tmp);
2625			switch (tmp) {
2626			case -EAGAIN:
2627				rc = -EAGAIN;
2628				break;
2629			case 0:
2630				break;
2631			default:
2632				failed_link = slave;
2633				rc = tmp;
2634				goto fail;
2635			}
2636		}
2637
2638		/* perform follow-up SRST if necessary */
2639		if (reset == hardreset &&
2640		    ata_eh_followup_srst_needed(link, rc)) {
2641			reset = softreset;
2642
2643			if (!reset) {
2644				ata_link_err(link,
2645	     "follow-up softreset required but no softreset available\n");
2646				failed_link = link;
2647				rc = -EINVAL;
2648				goto fail;
2649			}
2650
2651			ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2652			trace_ata_link_softreset_begin(link, classes, deadline);
2653			rc = ata_do_reset(link, reset, classes, deadline, true);
2654			trace_ata_link_softreset_end(link, classes, rc);
2655			if (rc) {
2656				failed_link = link;
2657				goto fail;
2658			}
2659		}
2660	} else {
2661		if (verbose)
2662			ata_link_info(link,
2663	"no reset method available, skipping reset\n");
2664		if (!(lflags & ATA_LFLAG_ASSUME_CLASS))
2665			lflags |= ATA_LFLAG_ASSUME_ATA;
2666	}
2667
2668	/*
2669	 * Post-reset processing
2670	 */
2671	ata_for_each_dev(dev, link, ALL) {
2672		/* After the reset, the device state is PIO 0 and the
2673		 * controller state is undefined.  Reset also wakes up
2674		 * drives from sleeping mode.
2675		 */
2676		dev->pio_mode = XFER_PIO_0;
2677		dev->flags &= ~ATA_DFLAG_SLEEPING;
2678
2679		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
2680			continue;
2681
2682		/* apply class override */
2683		if (lflags & ATA_LFLAG_ASSUME_ATA)
2684			classes[dev->devno] = ATA_DEV_ATA;
2685		else if (lflags & ATA_LFLAG_ASSUME_SEMB)
2686			classes[dev->devno] = ATA_DEV_SEMB_UNSUP;
2687	}
2688
2689	/* record current link speed */
2690	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0)
2691		link->sata_spd = (sstatus >> 4) & 0xf;
2692	if (slave && sata_scr_read(slave, SCR_STATUS, &sstatus) == 0)
2693		slave->sata_spd = (sstatus >> 4) & 0xf;
2694
2695	/* thaw the port */
2696	if (ata_is_host_link(link))
2697		ata_eh_thaw_port(ap);
2698
2699	/* postreset() should clear hardware SError.  Although SError
2700	 * is cleared during link resume, clearing SError here is
2701	 * necessary as some PHYs raise hotplug events after SRST.
2702	 * This introduces race condition where hotplug occurs between
2703	 * reset and here.  This race is mediated by cross checking
2704	 * link onlineness and classification result later.
2705	 */
2706	if (postreset) {
2707		postreset(link, classes);
2708		trace_ata_link_postreset(link, classes, rc);
2709		if (slave) {
2710			postreset(slave, classes);
2711			trace_ata_slave_postreset(slave, classes, rc);
2712		}
2713	}
2714
2715	/*
2716	 * Some controllers can't be frozen very well and may set spurious
2717	 * error conditions during reset.  Clear accumulated error
2718	 * information and re-thaw the port if frozen.  As reset is the
2719	 * final recovery action and we cross check link onlineness against
2720	 * device classification later, no hotplug event is lost by this.
2721	 */
2722	spin_lock_irqsave(link->ap->lock, flags);
2723	memset(&link->eh_info, 0, sizeof(link->eh_info));
2724	if (slave)
2725		memset(&slave->eh_info, 0, sizeof(link->eh_info));
2726	ap->pflags &= ~ATA_PFLAG_EH_PENDING;
2727	spin_unlock_irqrestore(link->ap->lock, flags);
2728
2729	if (ata_port_is_frozen(ap))
2730		ata_eh_thaw_port(ap);
2731
2732	/*
2733	 * Make sure onlineness and classification result correspond.
2734	 * Hotplug could have happened during reset and some
2735	 * controllers fail to wait while a drive is spinning up after
2736	 * being hotplugged causing misdetection.  By cross checking
2737	 * link on/offlineness and classification result, those
2738	 * conditions can be reliably detected and retried.
2739	 */
2740	nr_unknown = 0;
2741	ata_for_each_dev(dev, link, ALL) {
2742		if (ata_phys_link_online(ata_dev_phys_link(dev))) {
2743			if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2744				ata_dev_dbg(dev, "link online but device misclassified\n");
2745				classes[dev->devno] = ATA_DEV_NONE;
2746				nr_unknown++;
2747			}
2748		} else if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
2749			if (ata_class_enabled(classes[dev->devno]))
2750				ata_dev_dbg(dev,
2751					    "link offline, clearing class %d to NONE\n",
2752					    classes[dev->devno]);
2753			classes[dev->devno] = ATA_DEV_NONE;
2754		} else if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2755			ata_dev_dbg(dev,
2756				    "link status unknown, clearing UNKNOWN to NONE\n");
2757			classes[dev->devno] = ATA_DEV_NONE;
2758		}
2759	}
2760
2761	if (classify && nr_unknown) {
2762		if (try < max_tries) {
2763			ata_link_warn(link,
2764				      "link online but %d devices misclassified, retrying\n",
2765				      nr_unknown);
2766			failed_link = link;
2767			rc = -EAGAIN;
2768			goto fail;
2769		}
2770		ata_link_warn(link,
2771			      "link online but %d devices misclassified, "
2772			      "device detection might fail\n", nr_unknown);
2773	}
2774
2775	/* reset successful, schedule revalidation */
2776	ata_eh_done(link, NULL, ATA_EH_RESET);
2777	if (slave)
2778		ata_eh_done(slave, NULL, ATA_EH_RESET);
2779	ehc->last_reset = jiffies;		/* update to completion time */
2780	ehc->i.action |= ATA_EH_REVALIDATE;
2781	link->lpm_policy = ATA_LPM_UNKNOWN;	/* reset LPM state */
2782
2783	rc = 0;
2784 out:
2785	/* clear hotplug flag */
2786	ehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2787	if (slave)
2788		sehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2789
2790	spin_lock_irqsave(ap->lock, flags);
2791	ap->pflags &= ~ATA_PFLAG_RESETTING;
2792	spin_unlock_irqrestore(ap->lock, flags);
2793
2794	return rc;
2795
2796 fail:
2797	/* if SCR isn't accessible on a fan-out port, PMP needs to be reset */
2798	if (!ata_is_host_link(link) &&
2799	    sata_scr_read(link, SCR_STATUS, &sstatus))
2800		rc = -ERESTART;
2801
2802	if (try >= max_tries) {
2803		/*
2804		 * Thaw host port even if reset failed, so that the port
2805		 * can be retried on the next phy event.  This risks
2806		 * repeated EH runs but seems to be a better tradeoff than
2807		 * shutting down a port after a botched hotplug attempt.
2808		 */
2809		if (ata_is_host_link(link))
2810			ata_eh_thaw_port(ap);
 
 
2811		goto out;
2812	}
2813
2814	now = jiffies;
2815	if (time_before(now, deadline)) {
2816		unsigned long delta = deadline - now;
2817
2818		ata_link_warn(failed_link,
2819			"reset failed (errno=%d), retrying in %u secs\n",
2820			rc, DIV_ROUND_UP(jiffies_to_msecs(delta), 1000));
2821
2822		ata_eh_release(ap);
2823		while (delta)
2824			delta = schedule_timeout_uninterruptible(delta);
2825		ata_eh_acquire(ap);
2826	}
2827
2828	/*
2829	 * While disks spinup behind PMP, some controllers fail sending SRST.
2830	 * They need to be reset - as well as the PMP - before retrying.
2831	 */
2832	if (rc == -ERESTART) {
2833		if (ata_is_host_link(link))
2834			ata_eh_thaw_port(ap);
2835		goto out;
2836	}
2837
2838	if (try == max_tries - 1) {
2839		sata_down_spd_limit(link, 0);
2840		if (slave)
2841			sata_down_spd_limit(slave, 0);
2842	} else if (rc == -EPIPE)
2843		sata_down_spd_limit(failed_link, 0);
2844
2845	if (hardreset)
2846		reset = hardreset;
2847	goto retry;
2848}
2849
2850static inline void ata_eh_pull_park_action(struct ata_port *ap)
2851{
2852	struct ata_link *link;
2853	struct ata_device *dev;
2854	unsigned long flags;
2855
2856	/*
2857	 * This function can be thought of as an extended version of
2858	 * ata_eh_about_to_do() specially crafted to accommodate the
2859	 * requirements of ATA_EH_PARK handling. Since the EH thread
2860	 * does not leave the do {} while () loop in ata_eh_recover as
2861	 * long as the timeout for a park request to *one* device on
2862	 * the port has not expired, and since we still want to pick
2863	 * up park requests to other devices on the same port or
2864	 * timeout updates for the same device, we have to pull
2865	 * ATA_EH_PARK actions from eh_info into eh_context.i
2866	 * ourselves at the beginning of each pass over the loop.
2867	 *
2868	 * Additionally, all write accesses to &ap->park_req_pending
2869	 * through reinit_completion() (see below) or complete_all()
2870	 * (see ata_scsi_park_store()) are protected by the host lock.
2871	 * As a result we have that park_req_pending.done is zero on
2872	 * exit from this function, i.e. when ATA_EH_PARK actions for
2873	 * *all* devices on port ap have been pulled into the
2874	 * respective eh_context structs. If, and only if,
2875	 * park_req_pending.done is non-zero by the time we reach
2876	 * wait_for_completion_timeout(), another ATA_EH_PARK action
2877	 * has been scheduled for at least one of the devices on port
2878	 * ap and we have to cycle over the do {} while () loop in
2879	 * ata_eh_recover() again.
2880	 */
2881
2882	spin_lock_irqsave(ap->lock, flags);
2883	reinit_completion(&ap->park_req_pending);
2884	ata_for_each_link(link, ap, EDGE) {
2885		ata_for_each_dev(dev, link, ALL) {
2886			struct ata_eh_info *ehi = &link->eh_info;
2887
2888			link->eh_context.i.dev_action[dev->devno] |=
2889				ehi->dev_action[dev->devno] & ATA_EH_PARK;
2890			ata_eh_clear_action(link, dev, ehi, ATA_EH_PARK);
2891		}
2892	}
2893	spin_unlock_irqrestore(ap->lock, flags);
2894}
2895
2896static void ata_eh_park_issue_cmd(struct ata_device *dev, int park)
2897{
2898	struct ata_eh_context *ehc = &dev->link->eh_context;
2899	struct ata_taskfile tf;
2900	unsigned int err_mask;
2901
2902	ata_tf_init(dev, &tf);
2903	if (park) {
2904		ehc->unloaded_mask |= 1 << dev->devno;
2905		tf.command = ATA_CMD_IDLEIMMEDIATE;
2906		tf.feature = 0x44;
2907		tf.lbal = 0x4c;
2908		tf.lbam = 0x4e;
2909		tf.lbah = 0x55;
2910	} else {
2911		ehc->unloaded_mask &= ~(1 << dev->devno);
2912		tf.command = ATA_CMD_CHK_POWER;
2913	}
2914
2915	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
2916	tf.protocol = ATA_PROT_NODATA;
2917	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
2918	if (park && (err_mask || tf.lbal != 0xc4)) {
2919		ata_dev_err(dev, "head unload failed!\n");
2920		ehc->unloaded_mask &= ~(1 << dev->devno);
2921	}
2922}
2923
2924static int ata_eh_revalidate_and_attach(struct ata_link *link,
2925					struct ata_device **r_failed_dev)
2926{
2927	struct ata_port *ap = link->ap;
2928	struct ata_eh_context *ehc = &link->eh_context;
2929	struct ata_device *dev;
2930	unsigned int new_mask = 0;
2931	unsigned long flags;
2932	int rc = 0;
2933
2934	/* For PATA drive side cable detection to work, IDENTIFY must
2935	 * be done backwards such that PDIAG- is released by the slave
2936	 * device before the master device is identified.
2937	 */
2938	ata_for_each_dev(dev, link, ALL_REVERSE) {
2939		unsigned int action = ata_eh_dev_action(dev);
2940		unsigned int readid_flags = 0;
2941
2942		if (ehc->i.flags & ATA_EHI_DID_RESET)
2943			readid_flags |= ATA_READID_POSTRESET;
2944
2945		if ((action & ATA_EH_REVALIDATE) && ata_dev_enabled(dev)) {
2946			WARN_ON(dev->class == ATA_DEV_PMP);
2947
2948			/*
2949			 * The link may be in a deep sleep, wake it up.
2950			 *
2951			 * If the link is in deep sleep, ata_phys_link_offline()
2952			 * will return true, causing the revalidation to fail,
2953			 * which leads to a (potentially) needless hard reset.
2954			 *
2955			 * ata_eh_recover() will later restore the link policy
2956			 * to ap->target_lpm_policy after revalidation is done.
2957			 */
2958			if (link->lpm_policy > ATA_LPM_MAX_POWER) {
2959				rc = ata_eh_set_lpm(link, ATA_LPM_MAX_POWER,
2960						    r_failed_dev);
2961				if (rc)
2962					goto err;
2963			}
2964
2965			if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
2966				rc = -EIO;
2967				goto err;
2968			}
2969
2970			ata_eh_about_to_do(link, dev, ATA_EH_REVALIDATE);
2971			rc = ata_dev_revalidate(dev, ehc->classes[dev->devno],
2972						readid_flags);
2973			if (rc)
2974				goto err;
2975
2976			ata_eh_done(link, dev, ATA_EH_REVALIDATE);
2977
2978			/* Configuration may have changed, reconfigure
2979			 * transfer mode.
2980			 */
2981			ehc->i.flags |= ATA_EHI_SETMODE;
2982
2983			/* schedule the scsi_rescan_device() here */
2984			schedule_work(&(ap->scsi_rescan_task));
2985		} else if (dev->class == ATA_DEV_UNKNOWN &&
2986			   ehc->tries[dev->devno] &&
2987			   ata_class_enabled(ehc->classes[dev->devno])) {
2988			/* Temporarily set dev->class, it will be
2989			 * permanently set once all configurations are
2990			 * complete.  This is necessary because new
2991			 * device configuration is done in two
2992			 * separate loops.
2993			 */
2994			dev->class = ehc->classes[dev->devno];
2995
2996			if (dev->class == ATA_DEV_PMP)
2997				rc = sata_pmp_attach(dev);
2998			else
2999				rc = ata_dev_read_id(dev, &dev->class,
3000						     readid_flags, dev->id);
3001
3002			/* read_id might have changed class, store and reset */
3003			ehc->classes[dev->devno] = dev->class;
3004			dev->class = ATA_DEV_UNKNOWN;
3005
3006			switch (rc) {
3007			case 0:
3008				/* clear error info accumulated during probe */
3009				ata_ering_clear(&dev->ering);
3010				new_mask |= 1 << dev->devno;
3011				break;
3012			case -ENOENT:
3013				/* IDENTIFY was issued to non-existent
3014				 * device.  No need to reset.  Just
3015				 * thaw and ignore the device.
3016				 */
3017				ata_eh_thaw_port(ap);
3018				break;
3019			default:
3020				goto err;
3021			}
3022		}
3023	}
3024
3025	/* PDIAG- should have been released, ask cable type if post-reset */
3026	if ((ehc->i.flags & ATA_EHI_DID_RESET) && ata_is_host_link(link)) {
3027		if (ap->ops->cable_detect)
3028			ap->cbl = ap->ops->cable_detect(ap);
3029		ata_force_cbl(ap);
3030	}
3031
3032	/* Configure new devices forward such that user doesn't see
3033	 * device detection messages backwards.
3034	 */
3035	ata_for_each_dev(dev, link, ALL) {
3036		if (!(new_mask & (1 << dev->devno)))
3037			continue;
3038
3039		dev->class = ehc->classes[dev->devno];
3040
3041		if (dev->class == ATA_DEV_PMP)
3042			continue;
3043
3044		ehc->i.flags |= ATA_EHI_PRINTINFO;
3045		rc = ata_dev_configure(dev);
3046		ehc->i.flags &= ~ATA_EHI_PRINTINFO;
3047		if (rc) {
3048			dev->class = ATA_DEV_UNKNOWN;
3049			goto err;
3050		}
3051
3052		spin_lock_irqsave(ap->lock, flags);
3053		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
3054		spin_unlock_irqrestore(ap->lock, flags);
3055
3056		/* new device discovered, configure xfermode */
3057		ehc->i.flags |= ATA_EHI_SETMODE;
3058	}
3059
3060	return 0;
3061
3062 err:
3063	*r_failed_dev = dev;
3064	return rc;
3065}
3066
3067/**
3068 *	ata_set_mode - Program timings and issue SET FEATURES - XFER
3069 *	@link: link on which timings will be programmed
3070 *	@r_failed_dev: out parameter for failed device
3071 *
3072 *	Set ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3073 *	ata_set_mode() fails, pointer to the failing device is
3074 *	returned in @r_failed_dev.
3075 *
3076 *	LOCKING:
3077 *	PCI/etc. bus probe sem.
3078 *
3079 *	RETURNS:
3080 *	0 on success, negative errno otherwise
3081 */
3082int ata_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3083{
3084	struct ata_port *ap = link->ap;
3085	struct ata_device *dev;
3086	int rc;
3087
3088	/* if data transfer is verified, clear DUBIOUS_XFER on ering top */
3089	ata_for_each_dev(dev, link, ENABLED) {
3090		if (!(dev->flags & ATA_DFLAG_DUBIOUS_XFER)) {
3091			struct ata_ering_entry *ent;
3092
3093			ent = ata_ering_top(&dev->ering);
3094			if (ent)
3095				ent->eflags &= ~ATA_EFLAG_DUBIOUS_XFER;
3096		}
3097	}
3098
3099	/* has private set_mode? */
3100	if (ap->ops->set_mode)
3101		rc = ap->ops->set_mode(link, r_failed_dev);
3102	else
3103		rc = ata_do_set_mode(link, r_failed_dev);
3104
3105	/* if transfer mode has changed, set DUBIOUS_XFER on device */
3106	ata_for_each_dev(dev, link, ENABLED) {
3107		struct ata_eh_context *ehc = &link->eh_context;
3108		u8 saved_xfer_mode = ehc->saved_xfer_mode[dev->devno];
3109		u8 saved_ncq = !!(ehc->saved_ncq_enabled & (1 << dev->devno));
3110
3111		if (dev->xfer_mode != saved_xfer_mode ||
3112		    ata_ncq_enabled(dev) != saved_ncq)
3113			dev->flags |= ATA_DFLAG_DUBIOUS_XFER;
3114	}
3115
3116	return rc;
3117}
3118
3119/**
3120 *	atapi_eh_clear_ua - Clear ATAPI UNIT ATTENTION after reset
3121 *	@dev: ATAPI device to clear UA for
3122 *
3123 *	Resets and other operations can make an ATAPI device raise
3124 *	UNIT ATTENTION which causes the next operation to fail.  This
3125 *	function clears UA.
3126 *
3127 *	LOCKING:
3128 *	EH context (may sleep).
3129 *
3130 *	RETURNS:
3131 *	0 on success, -errno on failure.
3132 */
3133static int atapi_eh_clear_ua(struct ata_device *dev)
3134{
3135	int i;
3136
3137	for (i = 0; i < ATA_EH_UA_TRIES; i++) {
3138		u8 *sense_buffer = dev->link->ap->sector_buf;
3139		u8 sense_key = 0;
3140		unsigned int err_mask;
3141
3142		err_mask = atapi_eh_tur(dev, &sense_key);
3143		if (err_mask != 0 && err_mask != AC_ERR_DEV) {
3144			ata_dev_warn(dev,
3145				     "TEST_UNIT_READY failed (err_mask=0x%x)\n",
3146				     err_mask);
3147			return -EIO;
3148		}
3149
3150		if (!err_mask || sense_key != UNIT_ATTENTION)
3151			return 0;
3152
3153		err_mask = atapi_eh_request_sense(dev, sense_buffer, sense_key);
3154		if (err_mask) {
3155			ata_dev_warn(dev, "failed to clear "
3156				"UNIT ATTENTION (err_mask=0x%x)\n", err_mask);
3157			return -EIO;
3158		}
3159	}
3160
3161	ata_dev_warn(dev, "UNIT ATTENTION persists after %d tries\n",
3162		     ATA_EH_UA_TRIES);
3163
3164	return 0;
3165}
3166
3167/**
3168 *	ata_eh_maybe_retry_flush - Retry FLUSH if necessary
3169 *	@dev: ATA device which may need FLUSH retry
3170 *
3171 *	If @dev failed FLUSH, it needs to be reported upper layer
3172 *	immediately as it means that @dev failed to remap and already
3173 *	lost at least a sector and further FLUSH retrials won't make
3174 *	any difference to the lost sector.  However, if FLUSH failed
3175 *	for other reasons, for example transmission error, FLUSH needs
3176 *	to be retried.
3177 *
3178 *	This function determines whether FLUSH failure retry is
3179 *	necessary and performs it if so.
3180 *
3181 *	RETURNS:
3182 *	0 if EH can continue, -errno if EH needs to be repeated.
3183 */
3184static int ata_eh_maybe_retry_flush(struct ata_device *dev)
3185{
3186	struct ata_link *link = dev->link;
3187	struct ata_port *ap = link->ap;
3188	struct ata_queued_cmd *qc;
3189	struct ata_taskfile tf;
3190	unsigned int err_mask;
3191	int rc = 0;
3192
3193	/* did flush fail for this device? */
3194	if (!ata_tag_valid(link->active_tag))
3195		return 0;
3196
3197	qc = __ata_qc_from_tag(ap, link->active_tag);
3198	if (qc->dev != dev || (qc->tf.command != ATA_CMD_FLUSH_EXT &&
3199			       qc->tf.command != ATA_CMD_FLUSH))
3200		return 0;
3201
3202	/* if the device failed it, it should be reported to upper layers */
3203	if (qc->err_mask & AC_ERR_DEV)
3204		return 0;
3205
3206	/* flush failed for some other reason, give it another shot */
3207	ata_tf_init(dev, &tf);
3208
3209	tf.command = qc->tf.command;
3210	tf.flags |= ATA_TFLAG_DEVICE;
3211	tf.protocol = ATA_PROT_NODATA;
3212
3213	ata_dev_warn(dev, "retrying FLUSH 0x%x Emask 0x%x\n",
3214		       tf.command, qc->err_mask);
3215
3216	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
3217	if (!err_mask) {
3218		/*
3219		 * FLUSH is complete but there's no way to
3220		 * successfully complete a failed command from EH.
3221		 * Making sure retry is allowed at least once and
3222		 * retrying it should do the trick - whatever was in
3223		 * the cache is already on the platter and this won't
3224		 * cause infinite loop.
3225		 */
3226		qc->scsicmd->allowed = max(qc->scsicmd->allowed, 1);
3227	} else {
3228		ata_dev_warn(dev, "FLUSH failed Emask 0x%x\n",
3229			       err_mask);
3230		rc = -EIO;
3231
3232		/* if device failed it, report it to upper layers */
3233		if (err_mask & AC_ERR_DEV) {
3234			qc->err_mask |= AC_ERR_DEV;
3235			qc->result_tf = tf;
3236			if (!ata_port_is_frozen(ap))
3237				rc = 0;
3238		}
3239	}
3240	return rc;
3241}
3242
3243/**
3244 *	ata_eh_set_lpm - configure SATA interface power management
3245 *	@link: link to configure power management
3246 *	@policy: the link power management policy
3247 *	@r_failed_dev: out parameter for failed device
3248 *
3249 *	Enable SATA Interface power management.  This will enable
3250 *	Device Interface Power Management (DIPM) for min_power and
3251 *	medium_power_with_dipm policies, and then call driver specific
3252 *	callbacks for enabling Host Initiated Power management.
3253 *
3254 *	LOCKING:
3255 *	EH context.
3256 *
3257 *	RETURNS:
3258 *	0 on success, -errno on failure.
3259 */
3260static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
3261			  struct ata_device **r_failed_dev)
3262{
3263	struct ata_port *ap = ata_is_host_link(link) ? link->ap : NULL;
3264	struct ata_eh_context *ehc = &link->eh_context;
3265	struct ata_device *dev, *link_dev = NULL, *lpm_dev = NULL;
3266	enum ata_lpm_policy old_policy = link->lpm_policy;
3267	bool no_dipm = link->ap->flags & ATA_FLAG_NO_DIPM;
3268	unsigned int hints = ATA_LPM_EMPTY | ATA_LPM_HIPM;
3269	unsigned int err_mask;
3270	int rc;
3271
3272	/* if the link or host doesn't do LPM, noop */
3273	if (!IS_ENABLED(CONFIG_SATA_HOST) ||
3274	    (link->flags & ATA_LFLAG_NO_LPM) || (ap && !ap->ops->set_lpm))
3275		return 0;
3276
3277	/*
3278	 * DIPM is enabled only for MIN_POWER as some devices
3279	 * misbehave when the host NACKs transition to SLUMBER.  Order
3280	 * device and link configurations such that the host always
3281	 * allows DIPM requests.
3282	 */
3283	ata_for_each_dev(dev, link, ENABLED) {
3284		bool hipm = ata_id_has_hipm(dev->id);
3285		bool dipm = ata_id_has_dipm(dev->id) && !no_dipm;
3286
3287		/* find the first enabled and LPM enabled devices */
3288		if (!link_dev)
3289			link_dev = dev;
3290
3291		if (!lpm_dev && (hipm || dipm))
3292			lpm_dev = dev;
3293
3294		hints &= ~ATA_LPM_EMPTY;
3295		if (!hipm)
3296			hints &= ~ATA_LPM_HIPM;
3297
3298		/* disable DIPM before changing link config */
3299		if (policy < ATA_LPM_MED_POWER_WITH_DIPM && dipm) {
3300			err_mask = ata_dev_set_feature(dev,
3301					SETFEATURES_SATA_DISABLE, SATA_DIPM);
3302			if (err_mask && err_mask != AC_ERR_DEV) {
3303				ata_dev_warn(dev,
3304					     "failed to disable DIPM, Emask 0x%x\n",
3305					     err_mask);
3306				rc = -EIO;
3307				goto fail;
3308			}
3309		}
3310	}
3311
3312	if (ap) {
3313		rc = ap->ops->set_lpm(link, policy, hints);
3314		if (!rc && ap->slave_link)
3315			rc = ap->ops->set_lpm(ap->slave_link, policy, hints);
3316	} else
3317		rc = sata_pmp_set_lpm(link, policy, hints);
3318
3319	/*
3320	 * Attribute link config failure to the first (LPM) enabled
3321	 * device on the link.
3322	 */
3323	if (rc) {
3324		if (rc == -EOPNOTSUPP) {
3325			link->flags |= ATA_LFLAG_NO_LPM;
3326			return 0;
3327		}
3328		dev = lpm_dev ? lpm_dev : link_dev;
3329		goto fail;
3330	}
3331
3332	/*
3333	 * Low level driver acked the transition.  Issue DIPM command
3334	 * with the new policy set.
3335	 */
3336	link->lpm_policy = policy;
3337	if (ap && ap->slave_link)
3338		ap->slave_link->lpm_policy = policy;
3339
3340	/* host config updated, enable DIPM if transitioning to MIN_POWER */
3341	ata_for_each_dev(dev, link, ENABLED) {
3342		if (policy >= ATA_LPM_MED_POWER_WITH_DIPM && !no_dipm &&
3343		    ata_id_has_dipm(dev->id)) {
3344			err_mask = ata_dev_set_feature(dev,
3345					SETFEATURES_SATA_ENABLE, SATA_DIPM);
3346			if (err_mask && err_mask != AC_ERR_DEV) {
3347				ata_dev_warn(dev,
3348					"failed to enable DIPM, Emask 0x%x\n",
3349					err_mask);
3350				rc = -EIO;
3351				goto fail;
3352			}
3353		}
3354	}
3355
3356	link->last_lpm_change = jiffies;
3357	link->flags |= ATA_LFLAG_CHANGED;
3358
3359	return 0;
3360
3361fail:
3362	/* restore the old policy */
3363	link->lpm_policy = old_policy;
3364	if (ap && ap->slave_link)
3365		ap->slave_link->lpm_policy = old_policy;
3366
3367	/* if no device or only one more chance is left, disable LPM */
3368	if (!dev || ehc->tries[dev->devno] <= 2) {
3369		ata_link_warn(link, "disabling LPM on the link\n");
3370		link->flags |= ATA_LFLAG_NO_LPM;
3371	}
3372	if (r_failed_dev)
3373		*r_failed_dev = dev;
3374	return rc;
3375}
3376
3377int ata_link_nr_enabled(struct ata_link *link)
3378{
3379	struct ata_device *dev;
3380	int cnt = 0;
3381
3382	ata_for_each_dev(dev, link, ENABLED)
3383		cnt++;
3384	return cnt;
3385}
3386
3387static int ata_link_nr_vacant(struct ata_link *link)
3388{
3389	struct ata_device *dev;
3390	int cnt = 0;
3391
3392	ata_for_each_dev(dev, link, ALL)
3393		if (dev->class == ATA_DEV_UNKNOWN)
3394			cnt++;
3395	return cnt;
3396}
3397
3398static int ata_eh_skip_recovery(struct ata_link *link)
3399{
3400	struct ata_port *ap = link->ap;
3401	struct ata_eh_context *ehc = &link->eh_context;
3402	struct ata_device *dev;
3403
3404	/* skip disabled links */
3405	if (link->flags & ATA_LFLAG_DISABLED)
3406		return 1;
3407
3408	/* skip if explicitly requested */
3409	if (ehc->i.flags & ATA_EHI_NO_RECOVERY)
3410		return 1;
3411
3412	/* thaw frozen port and recover failed devices */
3413	if (ata_port_is_frozen(ap) || ata_link_nr_enabled(link))
3414		return 0;
3415
3416	/* reset at least once if reset is requested */
3417	if ((ehc->i.action & ATA_EH_RESET) &&
3418	    !(ehc->i.flags & ATA_EHI_DID_RESET))
3419		return 0;
3420
3421	/* skip if class codes for all vacant slots are ATA_DEV_NONE */
3422	ata_for_each_dev(dev, link, ALL) {
3423		if (dev->class == ATA_DEV_UNKNOWN &&
3424		    ehc->classes[dev->devno] != ATA_DEV_NONE)
3425			return 0;
3426	}
3427
3428	return 1;
3429}
3430
3431static int ata_count_probe_trials_cb(struct ata_ering_entry *ent, void *void_arg)
3432{
3433	u64 interval = msecs_to_jiffies(ATA_EH_PROBE_TRIAL_INTERVAL);
3434	u64 now = get_jiffies_64();
3435	int *trials = void_arg;
3436
3437	if ((ent->eflags & ATA_EFLAG_OLD_ER) ||
3438	    (ent->timestamp < now - min(now, interval)))
3439		return -1;
3440
3441	(*trials)++;
3442	return 0;
3443}
3444
3445static int ata_eh_schedule_probe(struct ata_device *dev)
3446{
3447	struct ata_eh_context *ehc = &dev->link->eh_context;
3448	struct ata_link *link = ata_dev_phys_link(dev);
3449	int trials = 0;
3450
3451	if (!(ehc->i.probe_mask & (1 << dev->devno)) ||
3452	    (ehc->did_probe_mask & (1 << dev->devno)))
3453		return 0;
3454
3455	ata_eh_detach_dev(dev);
3456	ata_dev_init(dev);
3457	ehc->did_probe_mask |= (1 << dev->devno);
3458	ehc->i.action |= ATA_EH_RESET;
3459	ehc->saved_xfer_mode[dev->devno] = 0;
3460	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
3461
3462	/* the link maybe in a deep sleep, wake it up */
3463	if (link->lpm_policy > ATA_LPM_MAX_POWER) {
3464		if (ata_is_host_link(link))
3465			link->ap->ops->set_lpm(link, ATA_LPM_MAX_POWER,
3466					       ATA_LPM_EMPTY);
3467		else
3468			sata_pmp_set_lpm(link, ATA_LPM_MAX_POWER,
3469					 ATA_LPM_EMPTY);
3470	}
3471
3472	/* Record and count probe trials on the ering.  The specific
3473	 * error mask used is irrelevant.  Because a successful device
3474	 * detection clears the ering, this count accumulates only if
3475	 * there are consecutive failed probes.
3476	 *
3477	 * If the count is equal to or higher than ATA_EH_PROBE_TRIALS
3478	 * in the last ATA_EH_PROBE_TRIAL_INTERVAL, link speed is
3479	 * forced to 1.5Gbps.
3480	 *
3481	 * This is to work around cases where failed link speed
3482	 * negotiation results in device misdetection leading to
3483	 * infinite DEVXCHG or PHRDY CHG events.
3484	 */
3485	ata_ering_record(&dev->ering, 0, AC_ERR_OTHER);
3486	ata_ering_map(&dev->ering, ata_count_probe_trials_cb, &trials);
3487
3488	if (trials > ATA_EH_PROBE_TRIALS)
3489		sata_down_spd_limit(link, 1);
3490
3491	return 1;
3492}
3493
3494static int ata_eh_handle_dev_fail(struct ata_device *dev, int err)
3495{
3496	struct ata_eh_context *ehc = &dev->link->eh_context;
3497
3498	/* -EAGAIN from EH routine indicates retry without prejudice.
3499	 * The requester is responsible for ensuring forward progress.
3500	 */
3501	if (err != -EAGAIN)
3502		ehc->tries[dev->devno]--;
3503
3504	switch (err) {
3505	case -ENODEV:
3506		/* device missing or wrong IDENTIFY data, schedule probing */
3507		ehc->i.probe_mask |= (1 << dev->devno);
3508		fallthrough;
3509	case -EINVAL:
3510		/* give it just one more chance */
3511		ehc->tries[dev->devno] = min(ehc->tries[dev->devno], 1);
3512		fallthrough;
3513	case -EIO:
3514		if (ehc->tries[dev->devno] == 1) {
3515			/* This is the last chance, better to slow
3516			 * down than lose it.
3517			 */
3518			sata_down_spd_limit(ata_dev_phys_link(dev), 0);
3519			if (dev->pio_mode > XFER_PIO_0)
3520				ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
3521		}
3522	}
3523
3524	if (ata_dev_enabled(dev) && !ehc->tries[dev->devno]) {
3525		/* disable device if it has used up all its chances */
3526		ata_dev_disable(dev);
3527
3528		/* detach if offline */
3529		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
3530			ata_eh_detach_dev(dev);
3531
3532		/* schedule probe if necessary */
3533		if (ata_eh_schedule_probe(dev)) {
3534			ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3535			memset(ehc->cmd_timeout_idx[dev->devno], 0,
3536			       sizeof(ehc->cmd_timeout_idx[dev->devno]));
3537		}
3538
3539		return 1;
3540	} else {
3541		ehc->i.action |= ATA_EH_RESET;
3542		return 0;
3543	}
3544}
3545
3546/**
3547 *	ata_eh_recover - recover host port after error
3548 *	@ap: host port to recover
3549 *	@prereset: prereset method (can be NULL)
3550 *	@softreset: softreset method (can be NULL)
3551 *	@hardreset: hardreset method (can be NULL)
3552 *	@postreset: postreset method (can be NULL)
3553 *	@r_failed_link: out parameter for failed link
3554 *
3555 *	This is the alpha and omega, eum and yang, heart and soul of
3556 *	libata exception handling.  On entry, actions required to
3557 *	recover each link and hotplug requests are recorded in the
3558 *	link's eh_context.  This function executes all the operations
3559 *	with appropriate retrials and fallbacks to resurrect failed
3560 *	devices, detach goners and greet newcomers.
3561 *
3562 *	LOCKING:
3563 *	Kernel thread context (may sleep).
3564 *
3565 *	RETURNS:
3566 *	0 on success, -errno on failure.
3567 */
3568int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
3569		   ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3570		   ata_postreset_fn_t postreset,
3571		   struct ata_link **r_failed_link)
3572{
3573	struct ata_link *link;
3574	struct ata_device *dev;
3575	int rc, nr_fails;
3576	unsigned long flags, deadline;
3577
3578	/* prep for recovery */
3579	ata_for_each_link(link, ap, EDGE) {
3580		struct ata_eh_context *ehc = &link->eh_context;
3581
3582		/* re-enable link? */
3583		if (ehc->i.action & ATA_EH_ENABLE_LINK) {
3584			ata_eh_about_to_do(link, NULL, ATA_EH_ENABLE_LINK);
3585			spin_lock_irqsave(ap->lock, flags);
3586			link->flags &= ~ATA_LFLAG_DISABLED;
3587			spin_unlock_irqrestore(ap->lock, flags);
3588			ata_eh_done(link, NULL, ATA_EH_ENABLE_LINK);
3589		}
3590
3591		ata_for_each_dev(dev, link, ALL) {
3592			if (link->flags & ATA_LFLAG_NO_RETRY)
3593				ehc->tries[dev->devno] = 1;
3594			else
3595				ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3596
3597			/* collect port action mask recorded in dev actions */
3598			ehc->i.action |= ehc->i.dev_action[dev->devno] &
3599					 ~ATA_EH_PERDEV_MASK;
3600			ehc->i.dev_action[dev->devno] &= ATA_EH_PERDEV_MASK;
3601
3602			/* process hotplug request */
3603			if (dev->flags & ATA_DFLAG_DETACH)
3604				ata_eh_detach_dev(dev);
3605
3606			/* schedule probe if necessary */
3607			if (!ata_dev_enabled(dev))
3608				ata_eh_schedule_probe(dev);
3609		}
3610	}
3611
3612 retry:
3613	rc = 0;
3614
3615	/* if UNLOADING, finish immediately */
3616	if (ap->pflags & ATA_PFLAG_UNLOADING)
3617		goto out;
3618
3619	/* prep for EH */
3620	ata_for_each_link(link, ap, EDGE) {
3621		struct ata_eh_context *ehc = &link->eh_context;
3622
3623		/* skip EH if possible. */
3624		if (ata_eh_skip_recovery(link))
3625			ehc->i.action = 0;
3626
3627		ata_for_each_dev(dev, link, ALL)
3628			ehc->classes[dev->devno] = ATA_DEV_UNKNOWN;
3629	}
3630
3631	/* reset */
3632	ata_for_each_link(link, ap, EDGE) {
3633		struct ata_eh_context *ehc = &link->eh_context;
3634
3635		if (!(ehc->i.action & ATA_EH_RESET))
3636			continue;
3637
3638		rc = ata_eh_reset(link, ata_link_nr_vacant(link),
3639				  prereset, softreset, hardreset, postreset);
3640		if (rc) {
3641			ata_link_err(link, "reset failed, giving up\n");
3642			goto out;
3643		}
3644	}
3645
3646	do {
3647		unsigned long now;
3648
3649		/*
3650		 * clears ATA_EH_PARK in eh_info and resets
3651		 * ap->park_req_pending
3652		 */
3653		ata_eh_pull_park_action(ap);
3654
3655		deadline = jiffies;
3656		ata_for_each_link(link, ap, EDGE) {
3657			ata_for_each_dev(dev, link, ALL) {
3658				struct ata_eh_context *ehc = &link->eh_context;
3659				unsigned long tmp;
3660
3661				if (dev->class != ATA_DEV_ATA &&
3662				    dev->class != ATA_DEV_ZAC)
3663					continue;
3664				if (!(ehc->i.dev_action[dev->devno] &
3665				      ATA_EH_PARK))
3666					continue;
3667				tmp = dev->unpark_deadline;
3668				if (time_before(deadline, tmp))
3669					deadline = tmp;
3670				else if (time_before_eq(tmp, jiffies))
3671					continue;
3672				if (ehc->unloaded_mask & (1 << dev->devno))
3673					continue;
3674
3675				ata_eh_park_issue_cmd(dev, 1);
3676			}
3677		}
3678
3679		now = jiffies;
3680		if (time_before_eq(deadline, now))
3681			break;
3682
3683		ata_eh_release(ap);
3684		deadline = wait_for_completion_timeout(&ap->park_req_pending,
3685						       deadline - now);
3686		ata_eh_acquire(ap);
3687	} while (deadline);
3688	ata_for_each_link(link, ap, EDGE) {
3689		ata_for_each_dev(dev, link, ALL) {
3690			if (!(link->eh_context.unloaded_mask &
3691			      (1 << dev->devno)))
3692				continue;
3693
3694			ata_eh_park_issue_cmd(dev, 0);
3695			ata_eh_done(link, dev, ATA_EH_PARK);
3696		}
3697	}
3698
3699	/* the rest */
3700	nr_fails = 0;
3701	ata_for_each_link(link, ap, PMP_FIRST) {
3702		struct ata_eh_context *ehc = &link->eh_context;
3703
3704		if (sata_pmp_attached(ap) && ata_is_host_link(link))
3705			goto config_lpm;
3706
3707		/* revalidate existing devices and attach new ones */
3708		rc = ata_eh_revalidate_and_attach(link, &dev);
3709		if (rc)
3710			goto rest_fail;
3711
3712		/* if PMP got attached, return, pmp EH will take care of it */
3713		if (link->device->class == ATA_DEV_PMP) {
3714			ehc->i.action = 0;
3715			return 0;
3716		}
3717
3718		/* configure transfer mode if necessary */
3719		if (ehc->i.flags & ATA_EHI_SETMODE) {
3720			rc = ata_set_mode(link, &dev);
3721			if (rc)
3722				goto rest_fail;
3723			ehc->i.flags &= ~ATA_EHI_SETMODE;
3724		}
3725
3726		/* If reset has been issued, clear UA to avoid
3727		 * disrupting the current users of the device.
3728		 */
3729		if (ehc->i.flags & ATA_EHI_DID_RESET) {
3730			ata_for_each_dev(dev, link, ALL) {
3731				if (dev->class != ATA_DEV_ATAPI)
3732					continue;
3733				rc = atapi_eh_clear_ua(dev);
3734				if (rc)
3735					goto rest_fail;
3736				if (zpodd_dev_enabled(dev))
3737					zpodd_post_poweron(dev);
3738			}
3739		}
3740
 
 
 
 
 
 
 
 
 
 
 
3741		/* retry flush if necessary */
3742		ata_for_each_dev(dev, link, ALL) {
3743			if (dev->class != ATA_DEV_ATA &&
3744			    dev->class != ATA_DEV_ZAC)
3745				continue;
3746			rc = ata_eh_maybe_retry_flush(dev);
3747			if (rc)
3748				goto rest_fail;
3749		}
3750
3751	config_lpm:
3752		/* configure link power saving */
3753		if (link->lpm_policy != ap->target_lpm_policy) {
3754			rc = ata_eh_set_lpm(link, ap->target_lpm_policy, &dev);
3755			if (rc)
3756				goto rest_fail;
3757		}
3758
3759		/* this link is okay now */
3760		ehc->i.flags = 0;
3761		continue;
3762
3763	rest_fail:
3764		nr_fails++;
3765		if (dev)
3766			ata_eh_handle_dev_fail(dev, rc);
3767
3768		if (ata_port_is_frozen(ap)) {
3769			/* PMP reset requires working host port.
3770			 * Can't retry if it's frozen.
3771			 */
3772			if (sata_pmp_attached(ap))
3773				goto out;
3774			break;
3775		}
3776	}
3777
3778	if (nr_fails)
3779		goto retry;
3780
3781 out:
3782	if (rc && r_failed_link)
3783		*r_failed_link = link;
3784
3785	return rc;
3786}
3787
3788/**
3789 *	ata_eh_finish - finish up EH
3790 *	@ap: host port to finish EH for
3791 *
3792 *	Recovery is complete.  Clean up EH states and retry or finish
3793 *	failed qcs.
3794 *
3795 *	LOCKING:
3796 *	None.
3797 */
3798void ata_eh_finish(struct ata_port *ap)
3799{
3800	struct ata_queued_cmd *qc;
3801	int tag;
3802
3803	/* retry or finish qcs */
3804	ata_qc_for_each_raw(ap, qc, tag) {
3805		if (!(qc->flags & ATA_QCFLAG_FAILED))
3806			continue;
3807
3808		if (qc->err_mask) {
3809			/* FIXME: Once EH migration is complete,
3810			 * generate sense data in this function,
3811			 * considering both err_mask and tf.
3812			 */
3813			if (qc->flags & ATA_QCFLAG_RETRY)
 
 
 
 
 
 
3814				ata_eh_qc_retry(qc);
3815			else
3816				ata_eh_qc_complete(qc);
 
3817		} else {
3818			if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
 
3819				ata_eh_qc_complete(qc);
3820			} else {
3821				/* feed zero TF to sense generation */
3822				memset(&qc->result_tf, 0, sizeof(qc->result_tf));
 
 
 
 
 
 
3823				ata_eh_qc_retry(qc);
3824			}
3825		}
3826	}
3827
3828	/* make sure nr_active_links is zero after EH */
3829	WARN_ON(ap->nr_active_links);
3830	ap->nr_active_links = 0;
3831}
3832
3833/**
3834 *	ata_do_eh - do standard error handling
3835 *	@ap: host port to handle error for
3836 *
3837 *	@prereset: prereset method (can be NULL)
3838 *	@softreset: softreset method (can be NULL)
3839 *	@hardreset: hardreset method (can be NULL)
3840 *	@postreset: postreset method (can be NULL)
3841 *
3842 *	Perform standard error handling sequence.
3843 *
3844 *	LOCKING:
3845 *	Kernel thread context (may sleep).
3846 */
3847void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
3848	       ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3849	       ata_postreset_fn_t postreset)
3850{
3851	struct ata_device *dev;
3852	int rc;
3853
3854	ata_eh_autopsy(ap);
3855	ata_eh_report(ap);
3856
3857	rc = ata_eh_recover(ap, prereset, softreset, hardreset, postreset,
3858			    NULL);
3859	if (rc) {
3860		ata_for_each_dev(dev, &ap->link, ALL)
3861			ata_dev_disable(dev);
3862	}
3863
3864	ata_eh_finish(ap);
3865}
3866
3867/**
3868 *	ata_std_error_handler - standard error handler
3869 *	@ap: host port to handle error for
3870 *
3871 *	Standard error handler
3872 *
3873 *	LOCKING:
3874 *	Kernel thread context (may sleep).
3875 */
3876void ata_std_error_handler(struct ata_port *ap)
3877{
3878	struct ata_port_operations *ops = ap->ops;
3879	ata_reset_fn_t hardreset = ops->hardreset;
3880
3881	/* ignore built-in hardreset if SCR access is not available */
3882	if (hardreset == sata_std_hardreset && !sata_scr_valid(&ap->link))
3883		hardreset = NULL;
3884
3885	ata_do_eh(ap, ops->prereset, ops->softreset, hardreset, ops->postreset);
3886}
3887EXPORT_SYMBOL_GPL(ata_std_error_handler);
3888
3889#ifdef CONFIG_PM
3890/**
3891 *	ata_eh_handle_port_suspend - perform port suspend operation
3892 *	@ap: port to suspend
3893 *
3894 *	Suspend @ap.
3895 *
3896 *	LOCKING:
3897 *	Kernel thread context (may sleep).
3898 */
3899static void ata_eh_handle_port_suspend(struct ata_port *ap)
3900{
3901	unsigned long flags;
3902	int rc = 0;
3903	struct ata_device *dev;
 
3904
3905	/* are we suspending? */
3906	spin_lock_irqsave(ap->lock, flags);
3907	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
3908	    ap->pm_mesg.event & PM_EVENT_RESUME) {
3909		spin_unlock_irqrestore(ap->lock, flags);
3910		return;
3911	}
3912	spin_unlock_irqrestore(ap->lock, flags);
3913
3914	WARN_ON(ap->pflags & ATA_PFLAG_SUSPENDED);
3915
 
 
 
 
 
 
3916	/*
3917	 * If we have a ZPODD attached, check its zero
3918	 * power ready status before the port is frozen.
3919	 * Only needed for runtime suspend.
3920	 */
3921	if (PMSG_IS_AUTO(ap->pm_mesg)) {
3922		ata_for_each_dev(dev, &ap->link, ENABLED) {
3923			if (zpodd_dev_enabled(dev))
3924				zpodd_on_suspend(dev);
3925		}
3926	}
3927
3928	/* suspend */
3929	ata_eh_freeze_port(ap);
3930
3931	if (ap->ops->port_suspend)
3932		rc = ap->ops->port_suspend(ap, ap->pm_mesg);
3933
3934	ata_acpi_set_state(ap, ap->pm_mesg);
3935
3936	/* update the flags */
3937	spin_lock_irqsave(ap->lock, flags);
3938
3939	ap->pflags &= ~ATA_PFLAG_PM_PENDING;
3940	if (rc == 0)
3941		ap->pflags |= ATA_PFLAG_SUSPENDED;
3942	else if (ata_port_is_frozen(ap))
3943		ata_port_schedule_eh(ap);
3944
3945	spin_unlock_irqrestore(ap->lock, flags);
3946
3947	return;
3948}
3949
3950/**
3951 *	ata_eh_handle_port_resume - perform port resume operation
3952 *	@ap: port to resume
3953 *
3954 *	Resume @ap.
3955 *
3956 *	LOCKING:
3957 *	Kernel thread context (may sleep).
3958 */
3959static void ata_eh_handle_port_resume(struct ata_port *ap)
3960{
3961	struct ata_link *link;
3962	struct ata_device *dev;
3963	unsigned long flags;
3964
3965	/* are we resuming? */
3966	spin_lock_irqsave(ap->lock, flags);
3967	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
3968	    !(ap->pm_mesg.event & PM_EVENT_RESUME)) {
3969		spin_unlock_irqrestore(ap->lock, flags);
3970		return;
3971	}
3972	spin_unlock_irqrestore(ap->lock, flags);
3973
3974	WARN_ON(!(ap->pflags & ATA_PFLAG_SUSPENDED));
3975
3976	/*
3977	 * Error timestamps are in jiffies which doesn't run while
3978	 * suspended and PHY events during resume isn't too uncommon.
3979	 * When the two are combined, it can lead to unnecessary speed
3980	 * downs if the machine is suspended and resumed repeatedly.
3981	 * Clear error history.
3982	 */
3983	ata_for_each_link(link, ap, HOST_FIRST)
3984		ata_for_each_dev(dev, link, ALL)
3985			ata_ering_clear(&dev->ering);
3986
3987	ata_acpi_set_state(ap, ap->pm_mesg);
3988
3989	if (ap->ops->port_resume)
3990		ap->ops->port_resume(ap);
3991
3992	/* tell ACPI that we're resuming */
3993	ata_acpi_on_resume(ap);
3994
3995	/* update the flags */
3996	spin_lock_irqsave(ap->lock, flags);
3997	ap->pflags &= ~(ATA_PFLAG_PM_PENDING | ATA_PFLAG_SUSPENDED);
 
3998	spin_unlock_irqrestore(ap->lock, flags);
3999}
4000#endif /* CONFIG_PM */
v6.8
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  libata-eh.c - libata error handling
   4 *
   5 *  Copyright 2006 Tejun Heo <htejun@gmail.com>
   6 *
   7 *  libata documentation is available via 'make {ps|pdf}docs',
   8 *  as Documentation/driver-api/libata.rst
   9 *
  10 *  Hardware documentation available from http://www.t13.org/ and
  11 *  http://www.sata-io.org/
  12 */
  13
  14#include <linux/kernel.h>
  15#include <linux/blkdev.h>
  16#include <linux/export.h>
  17#include <linux/pci.h>
  18#include <scsi/scsi.h>
  19#include <scsi/scsi_host.h>
  20#include <scsi/scsi_eh.h>
  21#include <scsi/scsi_device.h>
  22#include <scsi/scsi_cmnd.h>
  23#include <scsi/scsi_dbg.h>
  24#include "../scsi/scsi_transport_api.h"
  25
  26#include <linux/libata.h>
  27
  28#include <trace/events/libata.h>
  29#include "libata.h"
  30
  31enum {
  32	/* speed down verdicts */
  33	ATA_EH_SPDN_NCQ_OFF		= (1 << 0),
  34	ATA_EH_SPDN_SPEED_DOWN		= (1 << 1),
  35	ATA_EH_SPDN_FALLBACK_TO_PIO	= (1 << 2),
  36	ATA_EH_SPDN_KEEP_ERRORS		= (1 << 3),
  37
  38	/* error flags */
  39	ATA_EFLAG_IS_IO			= (1 << 0),
  40	ATA_EFLAG_DUBIOUS_XFER		= (1 << 1),
  41	ATA_EFLAG_OLD_ER                = (1 << 31),
  42
  43	/* error categories */
  44	ATA_ECAT_NONE			= 0,
  45	ATA_ECAT_ATA_BUS		= 1,
  46	ATA_ECAT_TOUT_HSM		= 2,
  47	ATA_ECAT_UNK_DEV		= 3,
  48	ATA_ECAT_DUBIOUS_NONE		= 4,
  49	ATA_ECAT_DUBIOUS_ATA_BUS	= 5,
  50	ATA_ECAT_DUBIOUS_TOUT_HSM	= 6,
  51	ATA_ECAT_DUBIOUS_UNK_DEV	= 7,
  52	ATA_ECAT_NR			= 8,
  53
  54	ATA_EH_CMD_DFL_TIMEOUT		=  5000,
  55
  56	/* always put at least this amount of time between resets */
  57	ATA_EH_RESET_COOL_DOWN		=  5000,
  58
  59	/* Waiting in ->prereset can never be reliable.  It's
  60	 * sometimes nice to wait there but it can't be depended upon;
  61	 * otherwise, we wouldn't be resetting.  Just give it enough
  62	 * time for most drives to spin up.
  63	 */
  64	ATA_EH_PRERESET_TIMEOUT		= 10000,
  65	ATA_EH_FASTDRAIN_INTERVAL	=  3000,
  66
  67	ATA_EH_UA_TRIES			= 5,
  68
  69	/* probe speed down parameters, see ata_eh_schedule_probe() */
  70	ATA_EH_PROBE_TRIAL_INTERVAL	= 60000,	/* 1 min */
  71	ATA_EH_PROBE_TRIALS		= 2,
  72};
  73
  74/* The following table determines how we sequence resets.  Each entry
  75 * represents timeout for that try.  The first try can be soft or
  76 * hardreset.  All others are hardreset if available.  In most cases
  77 * the first reset w/ 10sec timeout should succeed.  Following entries
  78 * are mostly for error handling, hotplug and those outlier devices that
  79 * take an exceptionally long time to recover from reset.
  80 */
  81static const unsigned int ata_eh_reset_timeouts[] = {
  82	10000,	/* most drives spin up by 10sec */
  83	10000,	/* > 99% working drives spin up before 20sec */
  84	35000,	/* give > 30 secs of idleness for outlier devices */
  85	 5000,	/* and sweet one last chance */
  86	UINT_MAX, /* > 1 min has elapsed, give up */
  87};
  88
  89static const unsigned int ata_eh_identify_timeouts[] = {
  90	 5000,	/* covers > 99% of successes and not too boring on failures */
  91	10000,  /* combined time till here is enough even for media access */
  92	30000,	/* for true idiots */
  93	UINT_MAX,
  94};
  95
  96static const unsigned int ata_eh_revalidate_timeouts[] = {
  97	15000,	/* Some drives are slow to read log pages when waking-up */
  98	15000,  /* combined time till here is enough even for media access */
  99	UINT_MAX,
 100};
 101
 102static const unsigned int ata_eh_flush_timeouts[] = {
 103	15000,	/* be generous with flush */
 104	15000,  /* ditto */
 105	30000,	/* and even more generous */
 106	UINT_MAX,
 107};
 108
 109static const unsigned int ata_eh_other_timeouts[] = {
 110	 5000,	/* same rationale as identify timeout */
 111	10000,	/* ditto */
 112	/* but no merciful 30sec for other commands, it just isn't worth it */
 113	UINT_MAX,
 114};
 115
 116struct ata_eh_cmd_timeout_ent {
 117	const u8		*commands;
 118	const unsigned int	*timeouts;
 119};
 120
 121/* The following table determines timeouts to use for EH internal
 122 * commands.  Each table entry is a command class and matches the
 123 * commands the entry applies to and the timeout table to use.
 124 *
 125 * On the retry after a command timed out, the next timeout value from
 126 * the table is used.  If the table doesn't contain further entries,
 127 * the last value is used.
 128 *
 129 * ehc->cmd_timeout_idx keeps track of which timeout to use per
 130 * command class, so if SET_FEATURES times out on the first try, the
 131 * next try will use the second timeout value only for that class.
 132 */
 133#define CMDS(cmds...)	(const u8 []){ cmds, 0 }
 134static const struct ata_eh_cmd_timeout_ent
 135ata_eh_cmd_timeout_table[ATA_EH_CMD_TIMEOUT_TABLE_SIZE] = {
 136	{ .commands = CMDS(ATA_CMD_ID_ATA, ATA_CMD_ID_ATAPI),
 137	  .timeouts = ata_eh_identify_timeouts, },
 138	{ .commands = CMDS(ATA_CMD_READ_LOG_EXT, ATA_CMD_READ_LOG_DMA_EXT),
 139	  .timeouts = ata_eh_revalidate_timeouts, },
 140	{ .commands = CMDS(ATA_CMD_READ_NATIVE_MAX, ATA_CMD_READ_NATIVE_MAX_EXT),
 141	  .timeouts = ata_eh_other_timeouts, },
 142	{ .commands = CMDS(ATA_CMD_SET_MAX, ATA_CMD_SET_MAX_EXT),
 143	  .timeouts = ata_eh_other_timeouts, },
 144	{ .commands = CMDS(ATA_CMD_SET_FEATURES),
 145	  .timeouts = ata_eh_other_timeouts, },
 146	{ .commands = CMDS(ATA_CMD_INIT_DEV_PARAMS),
 147	  .timeouts = ata_eh_other_timeouts, },
 148	{ .commands = CMDS(ATA_CMD_FLUSH, ATA_CMD_FLUSH_EXT),
 149	  .timeouts = ata_eh_flush_timeouts },
 150	{ .commands = CMDS(ATA_CMD_VERIFY),
 151	  .timeouts = ata_eh_reset_timeouts },
 152};
 153#undef CMDS
 154
 155static void __ata_port_freeze(struct ata_port *ap);
 156static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
 157			  struct ata_device **r_failed_dev);
 158#ifdef CONFIG_PM
 159static void ata_eh_handle_port_suspend(struct ata_port *ap);
 160static void ata_eh_handle_port_resume(struct ata_port *ap);
 161#else /* CONFIG_PM */
 162static void ata_eh_handle_port_suspend(struct ata_port *ap)
 163{ }
 164
 165static void ata_eh_handle_port_resume(struct ata_port *ap)
 166{ }
 167#endif /* CONFIG_PM */
 168
 169static __printf(2, 0) void __ata_ehi_pushv_desc(struct ata_eh_info *ehi,
 170				 const char *fmt, va_list args)
 171{
 172	ehi->desc_len += vscnprintf(ehi->desc + ehi->desc_len,
 173				     ATA_EH_DESC_LEN - ehi->desc_len,
 174				     fmt, args);
 175}
 176
 177/**
 178 *	__ata_ehi_push_desc - push error description without adding separator
 179 *	@ehi: target EHI
 180 *	@fmt: printf format string
 181 *
 182 *	Format string according to @fmt and append it to @ehi->desc.
 183 *
 184 *	LOCKING:
 185 *	spin_lock_irqsave(host lock)
 186 */
 187void __ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 188{
 189	va_list args;
 190
 191	va_start(args, fmt);
 192	__ata_ehi_pushv_desc(ehi, fmt, args);
 193	va_end(args);
 194}
 195EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
 196
 197/**
 198 *	ata_ehi_push_desc - push error description with separator
 199 *	@ehi: target EHI
 200 *	@fmt: printf format string
 201 *
 202 *	Format string according to @fmt and append it to @ehi->desc.
 203 *	If @ehi->desc is not empty, ", " is added in-between.
 204 *
 205 *	LOCKING:
 206 *	spin_lock_irqsave(host lock)
 207 */
 208void ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 209{
 210	va_list args;
 211
 212	if (ehi->desc_len)
 213		__ata_ehi_push_desc(ehi, ", ");
 214
 215	va_start(args, fmt);
 216	__ata_ehi_pushv_desc(ehi, fmt, args);
 217	va_end(args);
 218}
 219EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
 220
 221/**
 222 *	ata_ehi_clear_desc - clean error description
 223 *	@ehi: target EHI
 224 *
 225 *	Clear @ehi->desc.
 226 *
 227 *	LOCKING:
 228 *	spin_lock_irqsave(host lock)
 229 */
 230void ata_ehi_clear_desc(struct ata_eh_info *ehi)
 231{
 232	ehi->desc[0] = '\0';
 233	ehi->desc_len = 0;
 234}
 235EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
 236
 237/**
 238 *	ata_port_desc - append port description
 239 *	@ap: target ATA port
 240 *	@fmt: printf format string
 241 *
 242 *	Format string according to @fmt and append it to port
 243 *	description.  If port description is not empty, " " is added
 244 *	in-between.  This function is to be used while initializing
 245 *	ata_host.  The description is printed on host registration.
 246 *
 247 *	LOCKING:
 248 *	None.
 249 */
 250void ata_port_desc(struct ata_port *ap, const char *fmt, ...)
 251{
 252	va_list args;
 253
 254	WARN_ON(!(ap->pflags & ATA_PFLAG_INITIALIZING));
 255
 256	if (ap->link.eh_info.desc_len)
 257		__ata_ehi_push_desc(&ap->link.eh_info, " ");
 258
 259	va_start(args, fmt);
 260	__ata_ehi_pushv_desc(&ap->link.eh_info, fmt, args);
 261	va_end(args);
 262}
 263EXPORT_SYMBOL_GPL(ata_port_desc);
 264
 265#ifdef CONFIG_PCI
 266/**
 267 *	ata_port_pbar_desc - append PCI BAR description
 268 *	@ap: target ATA port
 269 *	@bar: target PCI BAR
 270 *	@offset: offset into PCI BAR
 271 *	@name: name of the area
 272 *
 273 *	If @offset is negative, this function formats a string which
 274 *	contains the name, address, size and type of the BAR and
 275 *	appends it to the port description.  If @offset is zero or
 276 *	positive, only name and offsetted address is appended.
 277 *
 278 *	LOCKING:
 279 *	None.
 280 */
 281void ata_port_pbar_desc(struct ata_port *ap, int bar, ssize_t offset,
 282			const char *name)
 283{
 284	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 285	char *type = "";
 286	unsigned long long start, len;
 287
 288	if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
 289		type = "m";
 290	else if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
 291		type = "i";
 292
 293	start = (unsigned long long)pci_resource_start(pdev, bar);
 294	len = (unsigned long long)pci_resource_len(pdev, bar);
 295
 296	if (offset < 0)
 297		ata_port_desc(ap, "%s %s%llu@0x%llx", name, type, len, start);
 298	else
 299		ata_port_desc(ap, "%s 0x%llx", name,
 300				start + (unsigned long long)offset);
 301}
 302EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
 303#endif /* CONFIG_PCI */
 304
 305static int ata_lookup_timeout_table(u8 cmd)
 306{
 307	int i;
 308
 309	for (i = 0; i < ATA_EH_CMD_TIMEOUT_TABLE_SIZE; i++) {
 310		const u8 *cur;
 311
 312		for (cur = ata_eh_cmd_timeout_table[i].commands; *cur; cur++)
 313			if (*cur == cmd)
 314				return i;
 315	}
 316
 317	return -1;
 318}
 319
 320/**
 321 *	ata_internal_cmd_timeout - determine timeout for an internal command
 322 *	@dev: target device
 323 *	@cmd: internal command to be issued
 324 *
 325 *	Determine timeout for internal command @cmd for @dev.
 326 *
 327 *	LOCKING:
 328 *	EH context.
 329 *
 330 *	RETURNS:
 331 *	Determined timeout.
 332 */
 333unsigned int ata_internal_cmd_timeout(struct ata_device *dev, u8 cmd)
 334{
 335	struct ata_eh_context *ehc = &dev->link->eh_context;
 336	int ent = ata_lookup_timeout_table(cmd);
 337	int idx;
 338
 339	if (ent < 0)
 340		return ATA_EH_CMD_DFL_TIMEOUT;
 341
 342	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 343	return ata_eh_cmd_timeout_table[ent].timeouts[idx];
 344}
 345
 346/**
 347 *	ata_internal_cmd_timed_out - notification for internal command timeout
 348 *	@dev: target device
 349 *	@cmd: internal command which timed out
 350 *
 351 *	Notify EH that internal command @cmd for @dev timed out.  This
 352 *	function should be called only for commands whose timeouts are
 353 *	determined using ata_internal_cmd_timeout().
 354 *
 355 *	LOCKING:
 356 *	EH context.
 357 */
 358void ata_internal_cmd_timed_out(struct ata_device *dev, u8 cmd)
 359{
 360	struct ata_eh_context *ehc = &dev->link->eh_context;
 361	int ent = ata_lookup_timeout_table(cmd);
 362	int idx;
 363
 364	if (ent < 0)
 365		return;
 366
 367	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 368	if (ata_eh_cmd_timeout_table[ent].timeouts[idx + 1] != UINT_MAX)
 369		ehc->cmd_timeout_idx[dev->devno][ent]++;
 370}
 371
 372static void ata_ering_record(struct ata_ering *ering, unsigned int eflags,
 373			     unsigned int err_mask)
 374{
 375	struct ata_ering_entry *ent;
 376
 377	WARN_ON(!err_mask);
 378
 379	ering->cursor++;
 380	ering->cursor %= ATA_ERING_SIZE;
 381
 382	ent = &ering->ring[ering->cursor];
 383	ent->eflags = eflags;
 384	ent->err_mask = err_mask;
 385	ent->timestamp = get_jiffies_64();
 386}
 387
 388static struct ata_ering_entry *ata_ering_top(struct ata_ering *ering)
 389{
 390	struct ata_ering_entry *ent = &ering->ring[ering->cursor];
 391
 392	if (ent->err_mask)
 393		return ent;
 394	return NULL;
 395}
 396
 397int ata_ering_map(struct ata_ering *ering,
 398		  int (*map_fn)(struct ata_ering_entry *, void *),
 399		  void *arg)
 400{
 401	int idx, rc = 0;
 402	struct ata_ering_entry *ent;
 403
 404	idx = ering->cursor;
 405	do {
 406		ent = &ering->ring[idx];
 407		if (!ent->err_mask)
 408			break;
 409		rc = map_fn(ent, arg);
 410		if (rc)
 411			break;
 412		idx = (idx - 1 + ATA_ERING_SIZE) % ATA_ERING_SIZE;
 413	} while (idx != ering->cursor);
 414
 415	return rc;
 416}
 417
 418static int ata_ering_clear_cb(struct ata_ering_entry *ent, void *void_arg)
 419{
 420	ent->eflags |= ATA_EFLAG_OLD_ER;
 421	return 0;
 422}
 423
 424static void ata_ering_clear(struct ata_ering *ering)
 425{
 426	ata_ering_map(ering, ata_ering_clear_cb, NULL);
 427}
 428
 429static unsigned int ata_eh_dev_action(struct ata_device *dev)
 430{
 431	struct ata_eh_context *ehc = &dev->link->eh_context;
 432
 433	return ehc->i.action | ehc->i.dev_action[dev->devno];
 434}
 435
 436static void ata_eh_clear_action(struct ata_link *link, struct ata_device *dev,
 437				struct ata_eh_info *ehi, unsigned int action)
 438{
 439	struct ata_device *tdev;
 440
 441	if (!dev) {
 442		ehi->action &= ~action;
 443		ata_for_each_dev(tdev, link, ALL)
 444			ehi->dev_action[tdev->devno] &= ~action;
 445	} else {
 446		/* doesn't make sense for port-wide EH actions */
 447		WARN_ON(!(action & ATA_EH_PERDEV_MASK));
 448
 449		/* break ehi->action into ehi->dev_action */
 450		if (ehi->action & action) {
 451			ata_for_each_dev(tdev, link, ALL)
 452				ehi->dev_action[tdev->devno] |=
 453					ehi->action & action;
 454			ehi->action &= ~action;
 455		}
 456
 457		/* turn off the specified per-dev action */
 458		ehi->dev_action[dev->devno] &= ~action;
 459	}
 460}
 461
 462/**
 463 *	ata_eh_acquire - acquire EH ownership
 464 *	@ap: ATA port to acquire EH ownership for
 465 *
 466 *	Acquire EH ownership for @ap.  This is the basic exclusion
 467 *	mechanism for ports sharing a host.  Only one port hanging off
 468 *	the same host can claim the ownership of EH.
 469 *
 470 *	LOCKING:
 471 *	EH context.
 472 */
 473void ata_eh_acquire(struct ata_port *ap)
 474{
 475	mutex_lock(&ap->host->eh_mutex);
 476	WARN_ON_ONCE(ap->host->eh_owner);
 477	ap->host->eh_owner = current;
 478}
 479
 480/**
 481 *	ata_eh_release - release EH ownership
 482 *	@ap: ATA port to release EH ownership for
 483 *
 484 *	Release EH ownership for @ap if the caller.  The caller must
 485 *	have acquired EH ownership using ata_eh_acquire() previously.
 486 *
 487 *	LOCKING:
 488 *	EH context.
 489 */
 490void ata_eh_release(struct ata_port *ap)
 491{
 492	WARN_ON_ONCE(ap->host->eh_owner != current);
 493	ap->host->eh_owner = NULL;
 494	mutex_unlock(&ap->host->eh_mutex);
 495}
 496
 497static void ata_eh_dev_disable(struct ata_device *dev)
 498{
 499	ata_acpi_on_disable(dev);
 500	ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 | ATA_DNXFER_QUIET);
 501	dev->class++;
 502
 503	/* From now till the next successful probe, ering is used to
 504	 * track probe failures.  Clear accumulated device error info.
 505	 */
 506	ata_ering_clear(&dev->ering);
 507}
 508
 509static void ata_eh_unload(struct ata_port *ap)
 510{
 511	struct ata_link *link;
 512	struct ata_device *dev;
 513	unsigned long flags;
 514
 515	/*
 516	 * Unless we are restarting, transition all enabled devices to
 517	 * standby power mode.
 518	 */
 519	if (system_state != SYSTEM_RESTART) {
 520		ata_for_each_link(link, ap, PMP_FIRST) {
 521			ata_for_each_dev(dev, link, ENABLED)
 522				ata_dev_power_set_standby(dev);
 523		}
 524	}
 525
 526	/*
 527	 * Restore SControl IPM and SPD for the next driver and
 528	 * disable attached devices.
 529	 */
 530	ata_for_each_link(link, ap, PMP_FIRST) {
 531		sata_scr_write(link, SCR_CONTROL, link->saved_scontrol & 0xff0);
 532		ata_for_each_dev(dev, link, ENABLED)
 533			ata_eh_dev_disable(dev);
 534	}
 535
 536	/* freeze and set UNLOADED */
 537	spin_lock_irqsave(ap->lock, flags);
 538
 539	ata_port_freeze(ap);			/* won't be thawed */
 540	ap->pflags &= ~ATA_PFLAG_EH_PENDING;	/* clear pending from freeze */
 541	ap->pflags |= ATA_PFLAG_UNLOADED;
 542
 543	spin_unlock_irqrestore(ap->lock, flags);
 544}
 545
 546/**
 547 *	ata_scsi_error - SCSI layer error handler callback
 548 *	@host: SCSI host on which error occurred
 549 *
 550 *	Handles SCSI-layer-thrown error events.
 551 *
 552 *	LOCKING:
 553 *	Inherited from SCSI layer (none, can sleep)
 554 *
 555 *	RETURNS:
 556 *	Zero.
 557 */
 558void ata_scsi_error(struct Scsi_Host *host)
 559{
 560	struct ata_port *ap = ata_shost_to_port(host);
 561	unsigned long flags;
 562	LIST_HEAD(eh_work_q);
 563
 564	spin_lock_irqsave(host->host_lock, flags);
 565	list_splice_init(&host->eh_cmd_q, &eh_work_q);
 566	spin_unlock_irqrestore(host->host_lock, flags);
 567
 568	ata_scsi_cmd_error_handler(host, ap, &eh_work_q);
 569
 570	/* If we timed raced normal completion and there is nothing to
 571	   recover nr_timedout == 0 why exactly are we doing error recovery ? */
 572	ata_scsi_port_error_handler(host, ap);
 573
 574	/* finish or retry handled scmd's and clean up */
 575	WARN_ON(!list_empty(&eh_work_q));
 576
 577}
 578
 579/**
 580 * ata_scsi_cmd_error_handler - error callback for a list of commands
 581 * @host:	scsi host containing the port
 582 * @ap:		ATA port within the host
 583 * @eh_work_q:	list of commands to process
 584 *
 585 * process the given list of commands and return those finished to the
 586 * ap->eh_done_q.  This function is the first part of the libata error
 587 * handler which processes a given list of failed commands.
 588 */
 589void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
 590				struct list_head *eh_work_q)
 591{
 592	int i;
 593	unsigned long flags;
 594	struct scsi_cmnd *scmd, *tmp;
 595	int nr_timedout = 0;
 596
 597	/* make sure sff pio task is not running */
 598	ata_sff_flush_pio_task(ap);
 599
 600	/* synchronize with host lock and sort out timeouts */
 601
 602	/*
 603	 * For EH, all qcs are finished in one of three ways -
 604	 * normal completion, error completion, and SCSI timeout.
 605	 * Both completions can race against SCSI timeout.  When normal
 606	 * completion wins, the qc never reaches EH.  When error
 607	 * completion wins, the qc has ATA_QCFLAG_EH set.
 608	 *
 609	 * When SCSI timeout wins, things are a bit more complex.
 610	 * Normal or error completion can occur after the timeout but
 611	 * before this point.  In such cases, both types of
 612	 * completions are honored.  A scmd is determined to have
 613	 * timed out iff its associated qc is active and not failed.
 614	 */
 615	spin_lock_irqsave(ap->lock, flags);
 
 
 
 
 
 
 
 
 
 616
 617	/*
 618	 * This must occur under the ap->lock as we don't want
 619	 * a polled recovery to race the real interrupt handler
 620	 *
 621	 * The lost_interrupt handler checks for any completed but
 622	 * non-notified command and completes much like an IRQ handler.
 623	 *
 624	 * We then fall into the error recovery code which will treat
 625	 * this as if normal completion won the race
 626	 */
 627	if (ap->ops->lost_interrupt)
 628		ap->ops->lost_interrupt(ap);
 629
 630	list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
 631		struct ata_queued_cmd *qc;
 632
 633		ata_qc_for_each_raw(ap, qc, i) {
 634			if (qc->flags & ATA_QCFLAG_ACTIVE &&
 635			    qc->scsicmd == scmd)
 636				break;
 637		}
 638
 639		if (i < ATA_MAX_QUEUE) {
 640			/* the scmd has an associated qc */
 641			if (!(qc->flags & ATA_QCFLAG_EH)) {
 642				/* which hasn't failed yet, timeout */
 643				qc->err_mask |= AC_ERR_TIMEOUT;
 644				qc->flags |= ATA_QCFLAG_EH;
 645				nr_timedout++;
 
 
 
 
 
 
 
 
 646			}
 647		} else {
 648			/* Normal completion occurred after
 649			 * SCSI timeout but before this point.
 650			 * Successfully complete it.
 651			 */
 652			scmd->retries = scmd->allowed;
 653			scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
 654		}
 655	}
 656
 657	/*
 658	 * If we have timed out qcs.  They belong to EH from
 659	 * this point but the state of the controller is
 660	 * unknown.  Freeze the port to make sure the IRQ
 661	 * handler doesn't diddle with those qcs.  This must
 662	 * be done atomically w.r.t. setting ATA_QCFLAG_EH.
 663	 */
 664	if (nr_timedout)
 665		__ata_port_freeze(ap);
 666
 667	/* initialize eh_tries */
 668	ap->eh_tries = ATA_EH_MAX_TRIES;
 669
 
 
 
 670	spin_unlock_irqrestore(ap->lock, flags);
 
 671}
 672EXPORT_SYMBOL(ata_scsi_cmd_error_handler);
 673
 674/**
 675 * ata_scsi_port_error_handler - recover the port after the commands
 676 * @host:	SCSI host containing the port
 677 * @ap:		the ATA port
 678 *
 679 * Handle the recovery of the port @ap after all the commands
 680 * have been recovered.
 681 */
 682void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap)
 683{
 684	unsigned long flags;
 685	struct ata_link *link;
 686
 687	/* acquire EH ownership */
 688	ata_eh_acquire(ap);
 
 
 
 
 689 repeat:
 690	/* kill fast drain timer */
 691	del_timer_sync(&ap->fastdrain_timer);
 692
 693	/* process port resume request */
 694	ata_eh_handle_port_resume(ap);
 695
 696	/* fetch & clear EH info */
 697	spin_lock_irqsave(ap->lock, flags);
 698
 699	ata_for_each_link(link, ap, HOST_FIRST) {
 700		struct ata_eh_context *ehc = &link->eh_context;
 701		struct ata_device *dev;
 
 
 
 
 
 
 
 
 
 
 
 
 
 702
 703		memset(&link->eh_context, 0, sizeof(link->eh_context));
 704		link->eh_context.i = link->eh_info;
 705		memset(&link->eh_info, 0, sizeof(link->eh_info));
 706
 707		ata_for_each_dev(dev, link, ENABLED) {
 708			int devno = dev->devno;
 709
 710			ehc->saved_xfer_mode[devno] = dev->xfer_mode;
 711			if (ata_ncq_enabled(dev))
 712				ehc->saved_ncq_enabled |= 1 << devno;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 713
 714			/* If we are resuming, wake up the device */
 715			if (ap->pflags & ATA_PFLAG_RESUMING)
 716				ehc->i.dev_action[devno] |= ATA_EH_SET_ACTIVE;
 
 
 
 
 
 
 717		}
 718	}
 719
 720	ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
 721	ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 722	ap->excl_link = NULL;	/* don't maintain exclusion over EH */
 
 
 
 
 
 
 
 723
 724	spin_unlock_irqrestore(ap->lock, flags);
 725
 726	/* invoke EH, skip if unloading or suspended */
 727	if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))
 728		ap->ops->error_handler(ap);
 729	else {
 730		/* if unloading, commence suicide */
 731		if ((ap->pflags & ATA_PFLAG_UNLOADING) &&
 732		    !(ap->pflags & ATA_PFLAG_UNLOADED))
 733			ata_eh_unload(ap);
 734		ata_eh_finish(ap);
 735	}
 736
 737	/* process port suspend request */
 738	ata_eh_handle_port_suspend(ap);
 739
 740	/*
 741	 * Exception might have happened after ->error_handler recovered the
 742	 * port but before this point.  Repeat EH in such case.
 743	 */
 744	spin_lock_irqsave(ap->lock, flags);
 745
 746	if (ap->pflags & ATA_PFLAG_EH_PENDING) {
 747		if (--ap->eh_tries) {
 748			spin_unlock_irqrestore(ap->lock, flags);
 749			goto repeat;
 750		}
 751		ata_port_err(ap,
 752			     "EH pending after %d tries, giving up\n",
 753			     ATA_EH_MAX_TRIES);
 754		ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 755	}
 756
 757	/* this run is complete, make sure EH info is clear */
 758	ata_for_each_link(link, ap, HOST_FIRST)
 759		memset(&link->eh_info, 0, sizeof(link->eh_info));
 760
 761	/*
 762	 * end eh (clear host_eh_scheduled) while holding ap->lock such that if
 763	 * exception occurs after this point but before EH completion, SCSI
 764	 * midlayer will re-initiate EH.
 765	 */
 766	ap->ops->end_eh(ap);
 767
 768	spin_unlock_irqrestore(ap->lock, flags);
 769	ata_eh_release(ap);
 770
 771	scsi_eh_flush_done_q(&ap->eh_done_q);
 772
 773	/* clean up */
 774	spin_lock_irqsave(ap->lock, flags);
 775
 776	ap->pflags &= ~ATA_PFLAG_RESUMING;
 777
 778	if (ap->pflags & ATA_PFLAG_LOADING)
 779		ap->pflags &= ~ATA_PFLAG_LOADING;
 780	else if ((ap->pflags & ATA_PFLAG_SCSI_HOTPLUG) &&
 781		!(ap->flags & ATA_FLAG_SAS_HOST))
 782		schedule_delayed_work(&ap->hotplug_task, 0);
 783
 784	if (ap->pflags & ATA_PFLAG_RECOVERED)
 785		ata_port_info(ap, "EH complete\n");
 786
 787	ap->pflags &= ~(ATA_PFLAG_SCSI_HOTPLUG | ATA_PFLAG_RECOVERED);
 788
 789	/* tell wait_eh that we're done */
 790	ap->pflags &= ~ATA_PFLAG_EH_IN_PROGRESS;
 791	wake_up_all(&ap->eh_wait_q);
 792
 793	spin_unlock_irqrestore(ap->lock, flags);
 794}
 795EXPORT_SYMBOL_GPL(ata_scsi_port_error_handler);
 796
 797/**
 798 *	ata_port_wait_eh - Wait for the currently pending EH to complete
 799 *	@ap: Port to wait EH for
 800 *
 801 *	Wait until the currently pending EH is complete.
 802 *
 803 *	LOCKING:
 804 *	Kernel thread context (may sleep).
 805 */
 806void ata_port_wait_eh(struct ata_port *ap)
 807{
 808	unsigned long flags;
 809	DEFINE_WAIT(wait);
 810
 811 retry:
 812	spin_lock_irqsave(ap->lock, flags);
 813
 814	while (ap->pflags & (ATA_PFLAG_EH_PENDING | ATA_PFLAG_EH_IN_PROGRESS)) {
 815		prepare_to_wait(&ap->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 816		spin_unlock_irqrestore(ap->lock, flags);
 817		schedule();
 818		spin_lock_irqsave(ap->lock, flags);
 819	}
 820	finish_wait(&ap->eh_wait_q, &wait);
 821
 822	spin_unlock_irqrestore(ap->lock, flags);
 823
 824	/* make sure SCSI EH is complete */
 825	if (scsi_host_in_recovery(ap->scsi_host)) {
 826		ata_msleep(ap, 10);
 827		goto retry;
 828	}
 829}
 830EXPORT_SYMBOL_GPL(ata_port_wait_eh);
 831
 832static unsigned int ata_eh_nr_in_flight(struct ata_port *ap)
 833{
 834	struct ata_queued_cmd *qc;
 835	unsigned int tag;
 836	unsigned int nr = 0;
 837
 838	/* count only non-internal commands */
 839	ata_qc_for_each(ap, qc, tag) {
 840		if (qc)
 841			nr++;
 842	}
 843
 844	return nr;
 845}
 846
 847void ata_eh_fastdrain_timerfn(struct timer_list *t)
 848{
 849	struct ata_port *ap = from_timer(ap, t, fastdrain_timer);
 850	unsigned long flags;
 851	unsigned int cnt;
 852
 853	spin_lock_irqsave(ap->lock, flags);
 854
 855	cnt = ata_eh_nr_in_flight(ap);
 856
 857	/* are we done? */
 858	if (!cnt)
 859		goto out_unlock;
 860
 861	if (cnt == ap->fastdrain_cnt) {
 862		struct ata_queued_cmd *qc;
 863		unsigned int tag;
 864
 865		/* No progress during the last interval, tag all
 866		 * in-flight qcs as timed out and freeze the port.
 867		 */
 868		ata_qc_for_each(ap, qc, tag) {
 869			if (qc)
 870				qc->err_mask |= AC_ERR_TIMEOUT;
 871		}
 872
 873		ata_port_freeze(ap);
 874	} else {
 875		/* some qcs have finished, give it another chance */
 876		ap->fastdrain_cnt = cnt;
 877		ap->fastdrain_timer.expires =
 878			ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 879		add_timer(&ap->fastdrain_timer);
 880	}
 881
 882 out_unlock:
 883	spin_unlock_irqrestore(ap->lock, flags);
 884}
 885
 886/**
 887 *	ata_eh_set_pending - set ATA_PFLAG_EH_PENDING and activate fast drain
 888 *	@ap: target ATA port
 889 *	@fastdrain: activate fast drain
 890 *
 891 *	Set ATA_PFLAG_EH_PENDING and activate fast drain if @fastdrain
 892 *	is non-zero and EH wasn't pending before.  Fast drain ensures
 893 *	that EH kicks in in timely manner.
 894 *
 895 *	LOCKING:
 896 *	spin_lock_irqsave(host lock)
 897 */
 898static void ata_eh_set_pending(struct ata_port *ap, int fastdrain)
 899{
 900	unsigned int cnt;
 901
 902	/* already scheduled? */
 903	if (ap->pflags & ATA_PFLAG_EH_PENDING)
 904		return;
 905
 906	ap->pflags |= ATA_PFLAG_EH_PENDING;
 907
 908	if (!fastdrain)
 909		return;
 910
 911	/* do we have in-flight qcs? */
 912	cnt = ata_eh_nr_in_flight(ap);
 913	if (!cnt)
 914		return;
 915
 916	/* activate fast drain */
 917	ap->fastdrain_cnt = cnt;
 918	ap->fastdrain_timer.expires =
 919		ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 920	add_timer(&ap->fastdrain_timer);
 921}
 922
 923/**
 924 *	ata_qc_schedule_eh - schedule qc for error handling
 925 *	@qc: command to schedule error handling for
 926 *
 927 *	Schedule error handling for @qc.  EH will kick in as soon as
 928 *	other commands are drained.
 929 *
 930 *	LOCKING:
 931 *	spin_lock_irqsave(host lock)
 932 */
 933void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
 934{
 935	struct ata_port *ap = qc->ap;
 936
 937	qc->flags |= ATA_QCFLAG_EH;
 
 
 938	ata_eh_set_pending(ap, 1);
 939
 940	/* The following will fail if timeout has already expired.
 941	 * ata_scsi_error() takes care of such scmds on EH entry.
 942	 * Note that ATA_QCFLAG_EH is unconditionally set after
 943	 * this function completes.
 944	 */
 945	blk_abort_request(scsi_cmd_to_rq(qc->scsicmd));
 946}
 947
 948/**
 949 * ata_std_sched_eh - non-libsas ata_ports issue eh with this common routine
 950 * @ap: ATA port to schedule EH for
 951 *
 952 *	LOCKING: inherited from ata_port_schedule_eh
 953 *	spin_lock_irqsave(host lock)
 954 */
 955void ata_std_sched_eh(struct ata_port *ap)
 956{
 
 
 957	if (ap->pflags & ATA_PFLAG_INITIALIZING)
 958		return;
 959
 960	ata_eh_set_pending(ap, 1);
 961	scsi_schedule_eh(ap->scsi_host);
 962
 963	trace_ata_std_sched_eh(ap);
 964}
 965EXPORT_SYMBOL_GPL(ata_std_sched_eh);
 966
 967/**
 968 * ata_std_end_eh - non-libsas ata_ports complete eh with this common routine
 969 * @ap: ATA port to end EH for
 970 *
 971 * In the libata object model there is a 1:1 mapping of ata_port to
 972 * shost, so host fields can be directly manipulated under ap->lock, in
 973 * the libsas case we need to hold a lock at the ha->level to coordinate
 974 * these events.
 975 *
 976 *	LOCKING:
 977 *	spin_lock_irqsave(host lock)
 978 */
 979void ata_std_end_eh(struct ata_port *ap)
 980{
 981	struct Scsi_Host *host = ap->scsi_host;
 982
 983	host->host_eh_scheduled = 0;
 984}
 985EXPORT_SYMBOL(ata_std_end_eh);
 986
 987
 988/**
 989 *	ata_port_schedule_eh - schedule error handling without a qc
 990 *	@ap: ATA port to schedule EH for
 991 *
 992 *	Schedule error handling for @ap.  EH will kick in as soon as
 993 *	all commands are drained.
 994 *
 995 *	LOCKING:
 996 *	spin_lock_irqsave(host lock)
 997 */
 998void ata_port_schedule_eh(struct ata_port *ap)
 999{
1000	/* see: ata_std_sched_eh, unless you know better */
1001	ap->ops->sched_eh(ap);
1002}
1003EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
1004
1005static int ata_do_link_abort(struct ata_port *ap, struct ata_link *link)
1006{
1007	struct ata_queued_cmd *qc;
1008	int tag, nr_aborted = 0;
1009
 
 
1010	/* we're gonna abort all commands, no need for fast drain */
1011	ata_eh_set_pending(ap, 0);
1012
1013	/* include internal tag in iteration */
1014	ata_qc_for_each_with_internal(ap, qc, tag) {
1015		if (qc && (!link || qc->dev->link == link)) {
1016			qc->flags |= ATA_QCFLAG_EH;
1017			ata_qc_complete(qc);
1018			nr_aborted++;
1019		}
1020	}
1021
1022	if (!nr_aborted)
1023		ata_port_schedule_eh(ap);
1024
1025	return nr_aborted;
1026}
1027
1028/**
1029 *	ata_link_abort - abort all qc's on the link
1030 *	@link: ATA link to abort qc's for
1031 *
1032 *	Abort all active qc's active on @link and schedule EH.
1033 *
1034 *	LOCKING:
1035 *	spin_lock_irqsave(host lock)
1036 *
1037 *	RETURNS:
1038 *	Number of aborted qc's.
1039 */
1040int ata_link_abort(struct ata_link *link)
1041{
1042	return ata_do_link_abort(link->ap, link);
1043}
1044EXPORT_SYMBOL_GPL(ata_link_abort);
1045
1046/**
1047 *	ata_port_abort - abort all qc's on the port
1048 *	@ap: ATA port to abort qc's for
1049 *
1050 *	Abort all active qc's of @ap and schedule EH.
1051 *
1052 *	LOCKING:
1053 *	spin_lock_irqsave(host_set lock)
1054 *
1055 *	RETURNS:
1056 *	Number of aborted qc's.
1057 */
1058int ata_port_abort(struct ata_port *ap)
1059{
1060	return ata_do_link_abort(ap, NULL);
1061}
1062EXPORT_SYMBOL_GPL(ata_port_abort);
1063
1064/**
1065 *	__ata_port_freeze - freeze port
1066 *	@ap: ATA port to freeze
1067 *
1068 *	This function is called when HSM violation or some other
1069 *	condition disrupts normal operation of the port.  Frozen port
1070 *	is not allowed to perform any operation until the port is
1071 *	thawed, which usually follows a successful reset.
1072 *
1073 *	ap->ops->freeze() callback can be used for freezing the port
1074 *	hardware-wise (e.g. mask interrupt and stop DMA engine).  If a
1075 *	port cannot be frozen hardware-wise, the interrupt handler
1076 *	must ack and clear interrupts unconditionally while the port
1077 *	is frozen.
1078 *
1079 *	LOCKING:
1080 *	spin_lock_irqsave(host lock)
1081 */
1082static void __ata_port_freeze(struct ata_port *ap)
1083{
 
 
1084	if (ap->ops->freeze)
1085		ap->ops->freeze(ap);
1086
1087	ap->pflags |= ATA_PFLAG_FROZEN;
1088
1089	trace_ata_port_freeze(ap);
1090}
1091
1092/**
1093 *	ata_port_freeze - abort & freeze port
1094 *	@ap: ATA port to freeze
1095 *
1096 *	Abort and freeze @ap.  The freeze operation must be called
1097 *	first, because some hardware requires special operations
1098 *	before the taskfile registers are accessible.
1099 *
1100 *	LOCKING:
1101 *	spin_lock_irqsave(host lock)
1102 *
1103 *	RETURNS:
1104 *	Number of aborted commands.
1105 */
1106int ata_port_freeze(struct ata_port *ap)
1107{
 
 
1108	__ata_port_freeze(ap);
1109
1110	return ata_port_abort(ap);
1111}
1112EXPORT_SYMBOL_GPL(ata_port_freeze);
1113
1114/**
1115 *	ata_eh_freeze_port - EH helper to freeze port
1116 *	@ap: ATA port to freeze
1117 *
1118 *	Freeze @ap.
1119 *
1120 *	LOCKING:
1121 *	None.
1122 */
1123void ata_eh_freeze_port(struct ata_port *ap)
1124{
1125	unsigned long flags;
1126
 
 
 
1127	spin_lock_irqsave(ap->lock, flags);
1128	__ata_port_freeze(ap);
1129	spin_unlock_irqrestore(ap->lock, flags);
1130}
1131EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
1132
1133/**
1134 *	ata_eh_thaw_port - EH helper to thaw port
1135 *	@ap: ATA port to thaw
1136 *
1137 *	Thaw frozen port @ap.
1138 *
1139 *	LOCKING:
1140 *	None.
1141 */
1142void ata_eh_thaw_port(struct ata_port *ap)
1143{
1144	unsigned long flags;
1145
 
 
 
1146	spin_lock_irqsave(ap->lock, flags);
1147
1148	ap->pflags &= ~ATA_PFLAG_FROZEN;
1149
1150	if (ap->ops->thaw)
1151		ap->ops->thaw(ap);
1152
1153	spin_unlock_irqrestore(ap->lock, flags);
1154
1155	trace_ata_port_thaw(ap);
1156}
1157
1158static void ata_eh_scsidone(struct scsi_cmnd *scmd)
1159{
1160	/* nada */
1161}
1162
1163static void __ata_eh_qc_complete(struct ata_queued_cmd *qc)
1164{
1165	struct ata_port *ap = qc->ap;
1166	struct scsi_cmnd *scmd = qc->scsicmd;
1167	unsigned long flags;
1168
1169	spin_lock_irqsave(ap->lock, flags);
1170	qc->scsidone = ata_eh_scsidone;
1171	__ata_qc_complete(qc);
1172	WARN_ON(ata_tag_valid(qc->tag));
1173	spin_unlock_irqrestore(ap->lock, flags);
1174
1175	scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
1176}
1177
1178/**
1179 *	ata_eh_qc_complete - Complete an active ATA command from EH
1180 *	@qc: Command to complete
1181 *
1182 *	Indicate to the mid and upper layers that an ATA command has
1183 *	completed.  To be used from EH.
1184 */
1185void ata_eh_qc_complete(struct ata_queued_cmd *qc)
1186{
1187	struct scsi_cmnd *scmd = qc->scsicmd;
1188	scmd->retries = scmd->allowed;
1189	__ata_eh_qc_complete(qc);
1190}
1191
1192/**
1193 *	ata_eh_qc_retry - Tell midlayer to retry an ATA command after EH
1194 *	@qc: Command to retry
1195 *
1196 *	Indicate to the mid and upper layers that an ATA command
1197 *	should be retried.  To be used from EH.
1198 *
1199 *	SCSI midlayer limits the number of retries to scmd->allowed.
1200 *	scmd->allowed is incremented for commands which get retried
1201 *	due to unrelated failures (qc->err_mask is zero).
1202 */
1203void ata_eh_qc_retry(struct ata_queued_cmd *qc)
1204{
1205	struct scsi_cmnd *scmd = qc->scsicmd;
1206	if (!qc->err_mask)
1207		scmd->allowed++;
1208	__ata_eh_qc_complete(qc);
1209}
1210
1211/**
1212 *	ata_dev_disable - disable ATA device
1213 *	@dev: ATA device to disable
1214 *
1215 *	Disable @dev.
1216 *
1217 *	Locking:
1218 *	EH context.
1219 */
1220void ata_dev_disable(struct ata_device *dev)
1221{
1222	if (!ata_dev_enabled(dev))
1223		return;
1224
1225	ata_dev_warn(dev, "disable device\n");
 
 
 
1226
1227	ata_eh_dev_disable(dev);
 
 
 
1228}
1229EXPORT_SYMBOL_GPL(ata_dev_disable);
1230
1231/**
1232 *	ata_eh_detach_dev - detach ATA device
1233 *	@dev: ATA device to detach
1234 *
1235 *	Detach @dev.
1236 *
1237 *	LOCKING:
1238 *	None.
1239 */
1240void ata_eh_detach_dev(struct ata_device *dev)
1241{
1242	struct ata_link *link = dev->link;
1243	struct ata_port *ap = link->ap;
1244	struct ata_eh_context *ehc = &link->eh_context;
1245	unsigned long flags;
1246
1247	/*
1248	 * If the device is still enabled, transition it to standby power mode
1249	 * (i.e. spin down HDDs) and disable it.
1250	 */
1251	if (ata_dev_enabled(dev)) {
1252		ata_dev_power_set_standby(dev);
1253		ata_eh_dev_disable(dev);
1254	}
1255
1256	spin_lock_irqsave(ap->lock, flags);
1257
1258	dev->flags &= ~ATA_DFLAG_DETACH;
1259
1260	if (ata_scsi_offline_dev(dev)) {
1261		dev->flags |= ATA_DFLAG_DETACHED;
1262		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
1263	}
1264
1265	/* clear per-dev EH info */
1266	ata_eh_clear_action(link, dev, &link->eh_info, ATA_EH_PERDEV_MASK);
1267	ata_eh_clear_action(link, dev, &link->eh_context.i, ATA_EH_PERDEV_MASK);
1268	ehc->saved_xfer_mode[dev->devno] = 0;
1269	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
1270
1271	spin_unlock_irqrestore(ap->lock, flags);
1272}
1273
1274/**
1275 *	ata_eh_about_to_do - about to perform eh_action
1276 *	@link: target ATA link
1277 *	@dev: target ATA dev for per-dev action (can be NULL)
1278 *	@action: action about to be performed
1279 *
1280 *	Called just before performing EH actions to clear related bits
1281 *	in @link->eh_info such that eh actions are not unnecessarily
1282 *	repeated.
1283 *
1284 *	LOCKING:
1285 *	None.
1286 */
1287void ata_eh_about_to_do(struct ata_link *link, struct ata_device *dev,
1288			unsigned int action)
1289{
1290	struct ata_port *ap = link->ap;
1291	struct ata_eh_info *ehi = &link->eh_info;
1292	struct ata_eh_context *ehc = &link->eh_context;
1293	unsigned long flags;
1294
1295	trace_ata_eh_about_to_do(link, dev ? dev->devno : 0, action);
1296
1297	spin_lock_irqsave(ap->lock, flags);
1298
1299	ata_eh_clear_action(link, dev, ehi, action);
1300
1301	/* About to take EH action, set RECOVERED.  Ignore actions on
1302	 * slave links as master will do them again.
1303	 */
1304	if (!(ehc->i.flags & ATA_EHI_QUIET) && link != ap->slave_link)
1305		ap->pflags |= ATA_PFLAG_RECOVERED;
1306
1307	spin_unlock_irqrestore(ap->lock, flags);
1308}
1309
1310/**
1311 *	ata_eh_done - EH action complete
1312 *	@link: ATA link for which EH actions are complete
1313 *	@dev: target ATA dev for per-dev action (can be NULL)
1314 *	@action: action just completed
1315 *
1316 *	Called right after performing EH actions to clear related bits
1317 *	in @link->eh_context.
1318 *
1319 *	LOCKING:
1320 *	None.
1321 */
1322void ata_eh_done(struct ata_link *link, struct ata_device *dev,
1323		 unsigned int action)
1324{
1325	struct ata_eh_context *ehc = &link->eh_context;
1326
1327	trace_ata_eh_done(link, dev ? dev->devno : 0, action);
1328
1329	ata_eh_clear_action(link, dev, &ehc->i, action);
1330}
1331
1332/**
1333 *	ata_err_string - convert err_mask to descriptive string
1334 *	@err_mask: error mask to convert to string
1335 *
1336 *	Convert @err_mask to descriptive string.  Errors are
1337 *	prioritized according to severity and only the most severe
1338 *	error is reported.
1339 *
1340 *	LOCKING:
1341 *	None.
1342 *
1343 *	RETURNS:
1344 *	Descriptive string for @err_mask
1345 */
1346static const char *ata_err_string(unsigned int err_mask)
1347{
1348	if (err_mask & AC_ERR_HOST_BUS)
1349		return "host bus error";
1350	if (err_mask & AC_ERR_ATA_BUS)
1351		return "ATA bus error";
1352	if (err_mask & AC_ERR_TIMEOUT)
1353		return "timeout";
1354	if (err_mask & AC_ERR_HSM)
1355		return "HSM violation";
1356	if (err_mask & AC_ERR_SYSTEM)
1357		return "internal error";
1358	if (err_mask & AC_ERR_MEDIA)
1359		return "media error";
1360	if (err_mask & AC_ERR_INVALID)
1361		return "invalid argument";
1362	if (err_mask & AC_ERR_DEV)
1363		return "device error";
1364	if (err_mask & AC_ERR_NCQ)
1365		return "NCQ error";
1366	if (err_mask & AC_ERR_NODEV_HINT)
1367		return "Polling detection error";
1368	return "unknown error";
1369}
1370
1371/**
1372 *	atapi_eh_tur - perform ATAPI TEST_UNIT_READY
1373 *	@dev: target ATAPI device
1374 *	@r_sense_key: out parameter for sense_key
1375 *
1376 *	Perform ATAPI TEST_UNIT_READY.
1377 *
1378 *	LOCKING:
1379 *	EH context (may sleep).
1380 *
1381 *	RETURNS:
1382 *	0 on success, AC_ERR_* mask on failure.
1383 */
1384unsigned int atapi_eh_tur(struct ata_device *dev, u8 *r_sense_key)
1385{
1386	u8 cdb[ATAPI_CDB_LEN] = { TEST_UNIT_READY, 0, 0, 0, 0, 0 };
1387	struct ata_taskfile tf;
1388	unsigned int err_mask;
1389
1390	ata_tf_init(dev, &tf);
1391
1392	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1393	tf.command = ATA_CMD_PACKET;
1394	tf.protocol = ATAPI_PROT_NODATA;
1395
1396	err_mask = ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
1397	if (err_mask == AC_ERR_DEV)
1398		*r_sense_key = tf.error >> 4;
1399	return err_mask;
1400}
1401
1402/**
1403 *	ata_eh_request_sense - perform REQUEST_SENSE_DATA_EXT
1404 *	@qc: qc to perform REQUEST_SENSE_SENSE_DATA_EXT to
1405 *
1406 *	Perform REQUEST_SENSE_DATA_EXT after the device reported CHECK
1407 *	SENSE.  This function is an EH helper.
1408 *
1409 *	LOCKING:
1410 *	Kernel thread context (may sleep).
1411 *
1412 *	RETURNS:
1413 *	true if sense data could be fetched, false otherwise.
1414 */
1415static bool ata_eh_request_sense(struct ata_queued_cmd *qc)
1416{
1417	struct scsi_cmnd *cmd = qc->scsicmd;
1418	struct ata_device *dev = qc->dev;
1419	struct ata_taskfile tf;
1420	unsigned int err_mask;
1421
1422	if (ata_port_is_frozen(qc->ap)) {
1423		ata_dev_warn(dev, "sense data available but port frozen\n");
1424		return false;
1425	}
1426
 
 
 
1427	if (!ata_id_sense_reporting_enabled(dev->id)) {
1428		ata_dev_warn(qc->dev, "sense data reporting disabled\n");
1429		return false;
1430	}
1431
1432	ata_tf_init(dev, &tf);
1433	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1434	tf.flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
1435	tf.command = ATA_CMD_REQ_SENSE_DATA;
1436	tf.protocol = ATA_PROT_NODATA;
1437
1438	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1439	/* Ignore err_mask; ATA_ERR might be set */
1440	if (tf.status & ATA_SENSE) {
1441		if (ata_scsi_sense_is_valid(tf.lbah, tf.lbam, tf.lbal)) {
1442			/* Set sense without also setting scsicmd->result */
1443			scsi_build_sense_buffer(dev->flags & ATA_DFLAG_D_SENSE,
1444						cmd->sense_buffer, tf.lbah,
1445						tf.lbam, tf.lbal);
1446			qc->flags |= ATA_QCFLAG_SENSE_VALID;
1447			return true;
1448		}
1449	} else {
1450		ata_dev_warn(dev, "request sense failed stat %02x emask %x\n",
1451			     tf.status, err_mask);
1452	}
1453
1454	return false;
1455}
1456
1457/**
1458 *	atapi_eh_request_sense - perform ATAPI REQUEST_SENSE
1459 *	@dev: device to perform REQUEST_SENSE to
1460 *	@sense_buf: result sense data buffer (SCSI_SENSE_BUFFERSIZE bytes long)
1461 *	@dfl_sense_key: default sense key to use
1462 *
1463 *	Perform ATAPI REQUEST_SENSE after the device reported CHECK
1464 *	SENSE.  This function is EH helper.
1465 *
1466 *	LOCKING:
1467 *	Kernel thread context (may sleep).
1468 *
1469 *	RETURNS:
1470 *	0 on success, AC_ERR_* mask on failure
1471 */
1472unsigned int atapi_eh_request_sense(struct ata_device *dev,
1473					   u8 *sense_buf, u8 dfl_sense_key)
1474{
1475	u8 cdb[ATAPI_CDB_LEN] =
1476		{ REQUEST_SENSE, 0, 0, 0, SCSI_SENSE_BUFFERSIZE, 0 };
1477	struct ata_port *ap = dev->link->ap;
1478	struct ata_taskfile tf;
1479
1480	memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
1481
1482	/* initialize sense_buf with the error register,
1483	 * for the case where they are -not- overwritten
1484	 */
1485	sense_buf[0] = 0x70;
1486	sense_buf[2] = dfl_sense_key;
1487
1488	/* some devices time out if garbage left in tf */
1489	ata_tf_init(dev, &tf);
1490
1491	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1492	tf.command = ATA_CMD_PACKET;
1493
1494	/* is it pointless to prefer PIO for "safety reasons"? */
1495	if (ap->flags & ATA_FLAG_PIO_DMA) {
1496		tf.protocol = ATAPI_PROT_DMA;
1497		tf.feature |= ATAPI_PKT_DMA;
1498	} else {
1499		tf.protocol = ATAPI_PROT_PIO;
1500		tf.lbam = SCSI_SENSE_BUFFERSIZE;
1501		tf.lbah = 0;
1502	}
1503
1504	return ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
1505				 sense_buf, SCSI_SENSE_BUFFERSIZE, 0);
1506}
1507
1508/**
1509 *	ata_eh_analyze_serror - analyze SError for a failed port
1510 *	@link: ATA link to analyze SError for
1511 *
1512 *	Analyze SError if available and further determine cause of
1513 *	failure.
1514 *
1515 *	LOCKING:
1516 *	None.
1517 */
1518static void ata_eh_analyze_serror(struct ata_link *link)
1519{
1520	struct ata_eh_context *ehc = &link->eh_context;
1521	u32 serror = ehc->i.serror;
1522	unsigned int err_mask = 0, action = 0;
1523	u32 hotplug_mask;
1524
1525	if (serror & (SERR_PERSISTENT | SERR_DATA)) {
1526		err_mask |= AC_ERR_ATA_BUS;
1527		action |= ATA_EH_RESET;
1528	}
1529	if (serror & SERR_PROTOCOL) {
1530		err_mask |= AC_ERR_HSM;
1531		action |= ATA_EH_RESET;
1532	}
1533	if (serror & SERR_INTERNAL) {
1534		err_mask |= AC_ERR_SYSTEM;
1535		action |= ATA_EH_RESET;
1536	}
1537
1538	/* Determine whether a hotplug event has occurred.  Both
1539	 * SError.N/X are considered hotplug events for enabled or
1540	 * host links.  For disabled PMP links, only N bit is
1541	 * considered as X bit is left at 1 for link plugging.
1542	 */
1543	if (link->lpm_policy > ATA_LPM_MAX_POWER)
1544		hotplug_mask = 0;	/* hotplug doesn't work w/ LPM */
1545	else if (!(link->flags & ATA_LFLAG_DISABLED) || ata_is_host_link(link))
1546		hotplug_mask = SERR_PHYRDY_CHG | SERR_DEV_XCHG;
1547	else
1548		hotplug_mask = SERR_PHYRDY_CHG;
1549
1550	if (serror & hotplug_mask)
1551		ata_ehi_hotplugged(&ehc->i);
1552
1553	ehc->i.err_mask |= err_mask;
1554	ehc->i.action |= action;
1555}
1556
1557/**
1558 *	ata_eh_analyze_tf - analyze taskfile of a failed qc
1559 *	@qc: qc to analyze
1560 *
1561 *	Analyze taskfile of @qc and further determine cause of
1562 *	failure.  This function also requests ATAPI sense data if
1563 *	available.
1564 *
1565 *	LOCKING:
1566 *	Kernel thread context (may sleep).
1567 *
1568 *	RETURNS:
1569 *	Determined recovery action
1570 */
1571static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc)
1572{
1573	const struct ata_taskfile *tf = &qc->result_tf;
1574	unsigned int tmp, action = 0;
1575	u8 stat = tf->status, err = tf->error;
1576
1577	if ((stat & (ATA_BUSY | ATA_DRQ | ATA_DRDY)) != ATA_DRDY) {
1578		qc->err_mask |= AC_ERR_HSM;
1579		return ATA_EH_RESET;
1580	}
1581
1582	if (stat & (ATA_ERR | ATA_DF)) {
1583		qc->err_mask |= AC_ERR_DEV;
1584		/*
1585		 * Sense data reporting does not work if the
1586		 * device fault bit is set.
1587		 */
1588		if (stat & ATA_DF)
1589			stat &= ~ATA_SENSE;
1590	} else {
1591		return 0;
1592	}
1593
1594	switch (qc->dev->class) {
1595	case ATA_DEV_ATA:
1596	case ATA_DEV_ZAC:
1597		/*
1598		 * Fetch the sense data explicitly if:
1599		 * -It was a non-NCQ command that failed, or
1600		 * -It was a NCQ command that failed, but the sense data
1601		 *  was not included in the NCQ command error log
1602		 *  (i.e. NCQ autosense is not supported by the device).
1603		 */
1604		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID) &&
1605		    (stat & ATA_SENSE) && ata_eh_request_sense(qc))
1606			set_status_byte(qc->scsicmd, SAM_STAT_CHECK_CONDITION);
1607		if (err & ATA_ICRC)
1608			qc->err_mask |= AC_ERR_ATA_BUS;
1609		if (err & (ATA_UNC | ATA_AMNF))
1610			qc->err_mask |= AC_ERR_MEDIA;
1611		if (err & ATA_IDNF)
1612			qc->err_mask |= AC_ERR_INVALID;
1613		break;
1614
1615	case ATA_DEV_ATAPI:
1616		if (!ata_port_is_frozen(qc->ap)) {
1617			tmp = atapi_eh_request_sense(qc->dev,
1618						qc->scsicmd->sense_buffer,
1619						qc->result_tf.error >> 4);
1620			if (!tmp)
1621				qc->flags |= ATA_QCFLAG_SENSE_VALID;
1622			else
1623				qc->err_mask |= tmp;
1624		}
1625	}
1626
1627	if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
1628		enum scsi_disposition ret = scsi_check_sense(qc->scsicmd);
1629		/*
1630		 * SUCCESS here means that the sense code could be
1631		 * evaluated and should be passed to the upper layers
1632		 * for correct evaluation.
1633		 * FAILED means the sense code could not be interpreted
1634		 * and the device would need to be reset.
1635		 * NEEDS_RETRY and ADD_TO_MLQUEUE means that the
1636		 * command would need to be retried.
1637		 */
1638		if (ret == NEEDS_RETRY || ret == ADD_TO_MLQUEUE) {
1639			qc->flags |= ATA_QCFLAG_RETRY;
1640			qc->err_mask |= AC_ERR_OTHER;
1641		} else if (ret != SUCCESS) {
1642			qc->err_mask |= AC_ERR_HSM;
1643		}
1644	}
1645	if (qc->err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT | AC_ERR_ATA_BUS))
1646		action |= ATA_EH_RESET;
1647
1648	return action;
1649}
1650
1651static int ata_eh_categorize_error(unsigned int eflags, unsigned int err_mask,
1652				   int *xfer_ok)
1653{
1654	int base = 0;
1655
1656	if (!(eflags & ATA_EFLAG_DUBIOUS_XFER))
1657		*xfer_ok = 1;
1658
1659	if (!*xfer_ok)
1660		base = ATA_ECAT_DUBIOUS_NONE;
1661
1662	if (err_mask & AC_ERR_ATA_BUS)
1663		return base + ATA_ECAT_ATA_BUS;
1664
1665	if (err_mask & AC_ERR_TIMEOUT)
1666		return base + ATA_ECAT_TOUT_HSM;
1667
1668	if (eflags & ATA_EFLAG_IS_IO) {
1669		if (err_mask & AC_ERR_HSM)
1670			return base + ATA_ECAT_TOUT_HSM;
1671		if ((err_mask &
1672		     (AC_ERR_DEV|AC_ERR_MEDIA|AC_ERR_INVALID)) == AC_ERR_DEV)
1673			return base + ATA_ECAT_UNK_DEV;
1674	}
1675
1676	return 0;
1677}
1678
1679struct speed_down_verdict_arg {
1680	u64 since;
1681	int xfer_ok;
1682	int nr_errors[ATA_ECAT_NR];
1683};
1684
1685static int speed_down_verdict_cb(struct ata_ering_entry *ent, void *void_arg)
1686{
1687	struct speed_down_verdict_arg *arg = void_arg;
1688	int cat;
1689
1690	if ((ent->eflags & ATA_EFLAG_OLD_ER) || (ent->timestamp < arg->since))
1691		return -1;
1692
1693	cat = ata_eh_categorize_error(ent->eflags, ent->err_mask,
1694				      &arg->xfer_ok);
1695	arg->nr_errors[cat]++;
1696
1697	return 0;
1698}
1699
1700/**
1701 *	ata_eh_speed_down_verdict - Determine speed down verdict
1702 *	@dev: Device of interest
1703 *
1704 *	This function examines error ring of @dev and determines
1705 *	whether NCQ needs to be turned off, transfer speed should be
1706 *	stepped down, or falling back to PIO is necessary.
1707 *
1708 *	ECAT_ATA_BUS	: ATA_BUS error for any command
1709 *
1710 *	ECAT_TOUT_HSM	: TIMEOUT for any command or HSM violation for
1711 *			  IO commands
1712 *
1713 *	ECAT_UNK_DEV	: Unknown DEV error for IO commands
1714 *
1715 *	ECAT_DUBIOUS_*	: Identical to above three but occurred while
1716 *			  data transfer hasn't been verified.
1717 *
1718 *	Verdicts are
1719 *
1720 *	NCQ_OFF		: Turn off NCQ.
1721 *
1722 *	SPEED_DOWN	: Speed down transfer speed but don't fall back
1723 *			  to PIO.
1724 *
1725 *	FALLBACK_TO_PIO	: Fall back to PIO.
1726 *
1727 *	Even if multiple verdicts are returned, only one action is
1728 *	taken per error.  An action triggered by non-DUBIOUS errors
1729 *	clears ering, while one triggered by DUBIOUS_* errors doesn't.
1730 *	This is to expedite speed down decisions right after device is
1731 *	initially configured.
1732 *
1733 *	The following are speed down rules.  #1 and #2 deal with
1734 *	DUBIOUS errors.
1735 *
1736 *	1. If more than one DUBIOUS_ATA_BUS or DUBIOUS_TOUT_HSM errors
1737 *	   occurred during last 5 mins, SPEED_DOWN and FALLBACK_TO_PIO.
1738 *
1739 *	2. If more than one DUBIOUS_TOUT_HSM or DUBIOUS_UNK_DEV errors
1740 *	   occurred during last 5 mins, NCQ_OFF.
1741 *
1742 *	3. If more than 8 ATA_BUS, TOUT_HSM or UNK_DEV errors
1743 *	   occurred during last 5 mins, FALLBACK_TO_PIO
1744 *
1745 *	4. If more than 3 TOUT_HSM or UNK_DEV errors occurred
1746 *	   during last 10 mins, NCQ_OFF.
1747 *
1748 *	5. If more than 3 ATA_BUS or TOUT_HSM errors, or more than 6
1749 *	   UNK_DEV errors occurred during last 10 mins, SPEED_DOWN.
1750 *
1751 *	LOCKING:
1752 *	Inherited from caller.
1753 *
1754 *	RETURNS:
1755 *	OR of ATA_EH_SPDN_* flags.
1756 */
1757static unsigned int ata_eh_speed_down_verdict(struct ata_device *dev)
1758{
1759	const u64 j5mins = 5LLU * 60 * HZ, j10mins = 10LLU * 60 * HZ;
1760	u64 j64 = get_jiffies_64();
1761	struct speed_down_verdict_arg arg;
1762	unsigned int verdict = 0;
1763
1764	/* scan past 5 mins of error history */
1765	memset(&arg, 0, sizeof(arg));
1766	arg.since = j64 - min(j64, j5mins);
1767	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1768
1769	if (arg.nr_errors[ATA_ECAT_DUBIOUS_ATA_BUS] +
1770	    arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] > 1)
1771		verdict |= ATA_EH_SPDN_SPEED_DOWN |
1772			ATA_EH_SPDN_FALLBACK_TO_PIO | ATA_EH_SPDN_KEEP_ERRORS;
1773
1774	if (arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] +
1775	    arg.nr_errors[ATA_ECAT_DUBIOUS_UNK_DEV] > 1)
1776		verdict |= ATA_EH_SPDN_NCQ_OFF | ATA_EH_SPDN_KEEP_ERRORS;
1777
1778	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1779	    arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1780	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1781		verdict |= ATA_EH_SPDN_FALLBACK_TO_PIO;
1782
1783	/* scan past 10 mins of error history */
1784	memset(&arg, 0, sizeof(arg));
1785	arg.since = j64 - min(j64, j10mins);
1786	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1787
1788	if (arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1789	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 3)
1790		verdict |= ATA_EH_SPDN_NCQ_OFF;
1791
1792	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1793	    arg.nr_errors[ATA_ECAT_TOUT_HSM] > 3 ||
1794	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1795		verdict |= ATA_EH_SPDN_SPEED_DOWN;
1796
1797	return verdict;
1798}
1799
1800/**
1801 *	ata_eh_speed_down - record error and speed down if necessary
1802 *	@dev: Failed device
1803 *	@eflags: mask of ATA_EFLAG_* flags
1804 *	@err_mask: err_mask of the error
1805 *
1806 *	Record error and examine error history to determine whether
1807 *	adjusting transmission speed is necessary.  It also sets
1808 *	transmission limits appropriately if such adjustment is
1809 *	necessary.
1810 *
1811 *	LOCKING:
1812 *	Kernel thread context (may sleep).
1813 *
1814 *	RETURNS:
1815 *	Determined recovery action.
1816 */
1817static unsigned int ata_eh_speed_down(struct ata_device *dev,
1818				unsigned int eflags, unsigned int err_mask)
1819{
1820	struct ata_link *link = ata_dev_phys_link(dev);
1821	int xfer_ok = 0;
1822	unsigned int verdict;
1823	unsigned int action = 0;
1824
1825	/* don't bother if Cat-0 error */
1826	if (ata_eh_categorize_error(eflags, err_mask, &xfer_ok) == 0)
1827		return 0;
1828
1829	/* record error and determine whether speed down is necessary */
1830	ata_ering_record(&dev->ering, eflags, err_mask);
1831	verdict = ata_eh_speed_down_verdict(dev);
1832
1833	/* turn off NCQ? */
1834	if ((verdict & ATA_EH_SPDN_NCQ_OFF) && ata_ncq_enabled(dev)) {
 
 
1835		dev->flags |= ATA_DFLAG_NCQ_OFF;
1836		ata_dev_warn(dev, "NCQ disabled due to excessive errors\n");
1837		goto done;
1838	}
1839
1840	/* speed down? */
1841	if (verdict & ATA_EH_SPDN_SPEED_DOWN) {
1842		/* speed down SATA link speed if possible */
1843		if (sata_down_spd_limit(link, 0) == 0) {
1844			action |= ATA_EH_RESET;
1845			goto done;
1846		}
1847
1848		/* lower transfer mode */
1849		if (dev->spdn_cnt < 2) {
1850			static const int dma_dnxfer_sel[] =
1851				{ ATA_DNXFER_DMA, ATA_DNXFER_40C };
1852			static const int pio_dnxfer_sel[] =
1853				{ ATA_DNXFER_PIO, ATA_DNXFER_FORCE_PIO0 };
1854			int sel;
1855
1856			if (dev->xfer_shift != ATA_SHIFT_PIO)
1857				sel = dma_dnxfer_sel[dev->spdn_cnt];
1858			else
1859				sel = pio_dnxfer_sel[dev->spdn_cnt];
1860
1861			dev->spdn_cnt++;
1862
1863			if (ata_down_xfermask_limit(dev, sel) == 0) {
1864				action |= ATA_EH_RESET;
1865				goto done;
1866			}
1867		}
1868	}
1869
1870	/* Fall back to PIO?  Slowing down to PIO is meaningless for
1871	 * SATA ATA devices.  Consider it only for PATA and SATAPI.
1872	 */
1873	if ((verdict & ATA_EH_SPDN_FALLBACK_TO_PIO) && (dev->spdn_cnt >= 2) &&
1874	    (link->ap->cbl != ATA_CBL_SATA || dev->class == ATA_DEV_ATAPI) &&
1875	    (dev->xfer_shift != ATA_SHIFT_PIO)) {
1876		if (ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO) == 0) {
1877			dev->spdn_cnt = 0;
1878			action |= ATA_EH_RESET;
1879			goto done;
1880		}
1881	}
1882
1883	return 0;
1884 done:
1885	/* device has been slowed down, blow error history */
1886	if (!(verdict & ATA_EH_SPDN_KEEP_ERRORS))
1887		ata_ering_clear(&dev->ering);
1888	return action;
1889}
1890
1891/**
1892 *	ata_eh_worth_retry - analyze error and decide whether to retry
1893 *	@qc: qc to possibly retry
1894 *
1895 *	Look at the cause of the error and decide if a retry
1896 * 	might be useful or not.  We don't want to retry media errors
1897 *	because the drive itself has probably already taken 10-30 seconds
1898 *	doing its own internal retries before reporting the failure.
1899 */
1900static inline int ata_eh_worth_retry(struct ata_queued_cmd *qc)
1901{
1902	if (qc->err_mask & AC_ERR_MEDIA)
1903		return 0;	/* don't retry media errors */
1904	if (qc->flags & ATA_QCFLAG_IO)
1905		return 1;	/* otherwise retry anything from fs stack */
1906	if (qc->err_mask & AC_ERR_INVALID)
1907		return 0;	/* don't retry these */
1908	return qc->err_mask != AC_ERR_DEV;  /* retry if not dev error */
1909}
1910
1911/**
1912 *      ata_eh_quiet - check if we need to be quiet about a command error
1913 *      @qc: qc to check
1914 *
1915 *      Look at the qc flags anbd its scsi command request flags to determine
1916 *      if we need to be quiet about the command failure.
1917 */
1918static inline bool ata_eh_quiet(struct ata_queued_cmd *qc)
1919{
1920	if (qc->scsicmd && scsi_cmd_to_rq(qc->scsicmd)->rq_flags & RQF_QUIET)
1921		qc->flags |= ATA_QCFLAG_QUIET;
1922	return qc->flags & ATA_QCFLAG_QUIET;
1923}
1924
1925static int ata_eh_read_sense_success_non_ncq(struct ata_link *link)
1926{
1927	struct ata_port *ap = link->ap;
1928	struct ata_queued_cmd *qc;
1929
1930	qc = __ata_qc_from_tag(ap, link->active_tag);
1931	if (!qc)
1932		return -EIO;
1933
1934	if (!(qc->flags & ATA_QCFLAG_EH) ||
1935	    !(qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD) ||
1936	    qc->err_mask)
1937		return -EIO;
1938
1939	if (!ata_eh_request_sense(qc))
1940		return -EIO;
1941
1942	/*
1943	 * If we have sense data, call scsi_check_sense() in order to set the
1944	 * correct SCSI ML byte (if any). No point in checking the return value,
1945	 * since the command has already completed successfully.
1946	 */
1947	scsi_check_sense(qc->scsicmd);
1948
1949	return 0;
1950}
1951
1952static void ata_eh_get_success_sense(struct ata_link *link)
1953{
1954	struct ata_eh_context *ehc = &link->eh_context;
1955	struct ata_device *dev = link->device;
1956	struct ata_port *ap = link->ap;
1957	struct ata_queued_cmd *qc;
1958	int tag, ret = 0;
1959
1960	if (!(ehc->i.dev_action[dev->devno] & ATA_EH_GET_SUCCESS_SENSE))
1961		return;
1962
1963	/* if frozen, we can't do much */
1964	if (ata_port_is_frozen(ap)) {
1965		ata_dev_warn(dev,
1966			"successful sense data available but port frozen\n");
1967		goto out;
1968	}
1969
1970	/*
1971	 * If the link has sactive set, then we have outstanding NCQ commands
1972	 * and have to read the Successful NCQ Commands log to get the sense
1973	 * data. Otherwise, we are dealing with a non-NCQ command and use
1974	 * request sense ext command to retrieve the sense data.
1975	 */
1976	if (link->sactive)
1977		ret = ata_eh_read_sense_success_ncq_log(link);
1978	else
1979		ret = ata_eh_read_sense_success_non_ncq(link);
1980	if (ret)
1981		goto out;
1982
1983	ata_eh_done(link, dev, ATA_EH_GET_SUCCESS_SENSE);
1984	return;
1985
1986out:
1987	/*
1988	 * If we failed to get sense data for a successful command that ought to
1989	 * have sense data, we cannot simply return BLK_STS_OK to user space.
1990	 * This is because we can't know if the sense data that we couldn't get
1991	 * was actually "DATA CURRENTLY UNAVAILABLE". Reporting such a command
1992	 * as success to user space would result in a silent data corruption.
1993	 * Thus, add a bogus ABORTED_COMMAND sense data to such commands, such
1994	 * that SCSI will report these commands as BLK_STS_IOERR to user space.
1995	 */
1996	ata_qc_for_each_raw(ap, qc, tag) {
1997		if (!(qc->flags & ATA_QCFLAG_EH) ||
1998		    !(qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD) ||
1999		    qc->err_mask ||
2000		    ata_dev_phys_link(qc->dev) != link)
2001			continue;
2002
2003		/* We managed to get sense for this success command, skip. */
2004		if (qc->flags & ATA_QCFLAG_SENSE_VALID)
2005			continue;
2006
2007		/* This success command did not have any sense data, skip. */
2008		if (!(qc->result_tf.status & ATA_SENSE))
2009			continue;
2010
2011		/* This success command had sense data, but we failed to get. */
2012		ata_scsi_set_sense(dev, qc->scsicmd, ABORTED_COMMAND, 0, 0);
2013		qc->flags |= ATA_QCFLAG_SENSE_VALID;
2014	}
2015	ata_eh_done(link, dev, ATA_EH_GET_SUCCESS_SENSE);
2016}
2017
2018/**
2019 *	ata_eh_link_autopsy - analyze error and determine recovery action
2020 *	@link: host link to perform autopsy on
2021 *
2022 *	Analyze why @link failed and determine which recovery actions
2023 *	are needed.  This function also sets more detailed AC_ERR_*
2024 *	values and fills sense data for ATAPI CHECK SENSE.
2025 *
2026 *	LOCKING:
2027 *	Kernel thread context (may sleep).
2028 */
2029static void ata_eh_link_autopsy(struct ata_link *link)
2030{
2031	struct ata_port *ap = link->ap;
2032	struct ata_eh_context *ehc = &link->eh_context;
2033	struct ata_queued_cmd *qc;
2034	struct ata_device *dev;
2035	unsigned int all_err_mask = 0, eflags = 0;
2036	int tag, nr_failed = 0, nr_quiet = 0;
2037	u32 serror;
2038	int rc;
2039
2040	if (ehc->i.flags & ATA_EHI_NO_AUTOPSY)
2041		return;
2042
2043	/* obtain and analyze SError */
2044	rc = sata_scr_read(link, SCR_ERROR, &serror);
2045	if (rc == 0) {
2046		ehc->i.serror |= serror;
2047		ata_eh_analyze_serror(link);
2048	} else if (rc != -EOPNOTSUPP) {
2049		/* SError read failed, force reset and probing */
2050		ehc->i.probe_mask |= ATA_ALL_DEVICES;
2051		ehc->i.action |= ATA_EH_RESET;
2052		ehc->i.err_mask |= AC_ERR_OTHER;
2053	}
2054
2055	/* analyze NCQ failure */
2056	ata_eh_analyze_ncq_error(link);
2057
2058	/*
2059	 * Check if this was a successful command that simply needs sense data.
2060	 * Since the sense data is not part of the completion, we need to fetch
2061	 * it using an additional command. Since this can't be done from irq
2062	 * context, the sense data for successful commands are fetched by EH.
2063	 */
2064	ata_eh_get_success_sense(link);
2065
2066	/* any real error trumps AC_ERR_OTHER */
2067	if (ehc->i.err_mask & ~AC_ERR_OTHER)
2068		ehc->i.err_mask &= ~AC_ERR_OTHER;
2069
2070	all_err_mask |= ehc->i.err_mask;
2071
2072	ata_qc_for_each_raw(ap, qc, tag) {
2073		if (!(qc->flags & ATA_QCFLAG_EH) ||
2074		    qc->flags & ATA_QCFLAG_RETRY ||
2075		    qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD ||
2076		    ata_dev_phys_link(qc->dev) != link)
2077			continue;
2078
2079		/* inherit upper level err_mask */
2080		qc->err_mask |= ehc->i.err_mask;
2081
2082		/* analyze TF */
2083		ehc->i.action |= ata_eh_analyze_tf(qc);
2084
2085		/* DEV errors are probably spurious in case of ATA_BUS error */
2086		if (qc->err_mask & AC_ERR_ATA_BUS)
2087			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_MEDIA |
2088					  AC_ERR_INVALID);
2089
2090		/* any real error trumps unknown error */
2091		if (qc->err_mask & ~AC_ERR_OTHER)
2092			qc->err_mask &= ~AC_ERR_OTHER;
2093
2094		/*
2095		 * SENSE_VALID trumps dev/unknown error and revalidation. Upper
2096		 * layers will determine whether the command is worth retrying
2097		 * based on the sense data and device class/type. Otherwise,
2098		 * determine directly if the command is worth retrying using its
2099		 * error mask and flags.
2100		 */
2101		if (qc->flags & ATA_QCFLAG_SENSE_VALID)
2102			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_OTHER);
2103		else if (ata_eh_worth_retry(qc))
2104			qc->flags |= ATA_QCFLAG_RETRY;
2105
2106		/* accumulate error info */
2107		ehc->i.dev = qc->dev;
2108		all_err_mask |= qc->err_mask;
2109		if (qc->flags & ATA_QCFLAG_IO)
2110			eflags |= ATA_EFLAG_IS_IO;
2111		trace_ata_eh_link_autopsy_qc(qc);
2112
2113		/* Count quiet errors */
2114		if (ata_eh_quiet(qc))
2115			nr_quiet++;
2116		nr_failed++;
2117	}
2118
2119	/* If all failed commands requested silence, then be quiet */
2120	if (nr_quiet == nr_failed)
2121		ehc->i.flags |= ATA_EHI_QUIET;
2122
2123	/* enforce default EH actions */
2124	if (ata_port_is_frozen(ap) ||
2125	    all_err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT))
2126		ehc->i.action |= ATA_EH_RESET;
2127	else if (((eflags & ATA_EFLAG_IS_IO) && all_err_mask) ||
2128		 (!(eflags & ATA_EFLAG_IS_IO) && (all_err_mask & ~AC_ERR_DEV)))
2129		ehc->i.action |= ATA_EH_REVALIDATE;
2130
2131	/* If we have offending qcs and the associated failed device,
2132	 * perform per-dev EH action only on the offending device.
2133	 */
2134	if (ehc->i.dev) {
2135		ehc->i.dev_action[ehc->i.dev->devno] |=
2136			ehc->i.action & ATA_EH_PERDEV_MASK;
2137		ehc->i.action &= ~ATA_EH_PERDEV_MASK;
2138	}
2139
2140	/* propagate timeout to host link */
2141	if ((all_err_mask & AC_ERR_TIMEOUT) && !ata_is_host_link(link))
2142		ap->link.eh_context.i.err_mask |= AC_ERR_TIMEOUT;
2143
2144	/* record error and consider speeding down */
2145	dev = ehc->i.dev;
2146	if (!dev && ((ata_link_max_devices(link) == 1 &&
2147		      ata_dev_enabled(link->device))))
2148	    dev = link->device;
2149
2150	if (dev) {
2151		if (dev->flags & ATA_DFLAG_DUBIOUS_XFER)
2152			eflags |= ATA_EFLAG_DUBIOUS_XFER;
2153		ehc->i.action |= ata_eh_speed_down(dev, eflags, all_err_mask);
2154		trace_ata_eh_link_autopsy(dev, ehc->i.action, all_err_mask);
2155	}
2156}
2157
2158/**
2159 *	ata_eh_autopsy - analyze error and determine recovery action
2160 *	@ap: host port to perform autopsy on
2161 *
2162 *	Analyze all links of @ap and determine why they failed and
2163 *	which recovery actions are needed.
2164 *
2165 *	LOCKING:
2166 *	Kernel thread context (may sleep).
2167 */
2168void ata_eh_autopsy(struct ata_port *ap)
2169{
2170	struct ata_link *link;
2171
2172	ata_for_each_link(link, ap, EDGE)
2173		ata_eh_link_autopsy(link);
2174
2175	/* Handle the frigging slave link.  Autopsy is done similarly
2176	 * but actions and flags are transferred over to the master
2177	 * link and handled from there.
2178	 */
2179	if (ap->slave_link) {
2180		struct ata_eh_context *mehc = &ap->link.eh_context;
2181		struct ata_eh_context *sehc = &ap->slave_link->eh_context;
2182
2183		/* transfer control flags from master to slave */
2184		sehc->i.flags |= mehc->i.flags & ATA_EHI_TO_SLAVE_MASK;
2185
2186		/* perform autopsy on the slave link */
2187		ata_eh_link_autopsy(ap->slave_link);
2188
2189		/* transfer actions from slave to master and clear slave */
2190		ata_eh_about_to_do(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2191		mehc->i.action		|= sehc->i.action;
2192		mehc->i.dev_action[1]	|= sehc->i.dev_action[1];
2193		mehc->i.flags		|= sehc->i.flags;
2194		ata_eh_done(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2195	}
2196
2197	/* Autopsy of fanout ports can affect host link autopsy.
2198	 * Perform host link autopsy last.
2199	 */
2200	if (sata_pmp_attached(ap))
2201		ata_eh_link_autopsy(&ap->link);
2202}
2203
2204/**
2205 *	ata_get_cmd_name - get name for ATA command
2206 *	@command: ATA command code to get name for
2207 *
2208 *	Return a textual name of the given command or "unknown"
2209 *
2210 *	LOCKING:
2211 *	None
2212 */
2213const char *ata_get_cmd_name(u8 command)
2214{
2215#ifdef CONFIG_ATA_VERBOSE_ERROR
2216	static const struct
2217	{
2218		u8 command;
2219		const char *text;
2220	} cmd_descr[] = {
2221		{ ATA_CMD_DEV_RESET,		"DEVICE RESET" },
2222		{ ATA_CMD_CHK_POWER,		"CHECK POWER MODE" },
2223		{ ATA_CMD_STANDBY,		"STANDBY" },
2224		{ ATA_CMD_IDLE,			"IDLE" },
2225		{ ATA_CMD_EDD,			"EXECUTE DEVICE DIAGNOSTIC" },
2226		{ ATA_CMD_DOWNLOAD_MICRO,	"DOWNLOAD MICROCODE" },
2227		{ ATA_CMD_DOWNLOAD_MICRO_DMA,	"DOWNLOAD MICROCODE DMA" },
2228		{ ATA_CMD_NOP,			"NOP" },
2229		{ ATA_CMD_FLUSH,		"FLUSH CACHE" },
2230		{ ATA_CMD_FLUSH_EXT,		"FLUSH CACHE EXT" },
2231		{ ATA_CMD_ID_ATA,		"IDENTIFY DEVICE" },
2232		{ ATA_CMD_ID_ATAPI,		"IDENTIFY PACKET DEVICE" },
2233		{ ATA_CMD_SERVICE,		"SERVICE" },
2234		{ ATA_CMD_READ,			"READ DMA" },
2235		{ ATA_CMD_READ_EXT,		"READ DMA EXT" },
2236		{ ATA_CMD_READ_QUEUED,		"READ DMA QUEUED" },
2237		{ ATA_CMD_READ_STREAM_EXT,	"READ STREAM EXT" },
2238		{ ATA_CMD_READ_STREAM_DMA_EXT,  "READ STREAM DMA EXT" },
2239		{ ATA_CMD_WRITE,		"WRITE DMA" },
2240		{ ATA_CMD_WRITE_EXT,		"WRITE DMA EXT" },
2241		{ ATA_CMD_WRITE_QUEUED,		"WRITE DMA QUEUED EXT" },
2242		{ ATA_CMD_WRITE_STREAM_EXT,	"WRITE STREAM EXT" },
2243		{ ATA_CMD_WRITE_STREAM_DMA_EXT, "WRITE STREAM DMA EXT" },
2244		{ ATA_CMD_WRITE_FUA_EXT,	"WRITE DMA FUA EXT" },
2245		{ ATA_CMD_WRITE_QUEUED_FUA_EXT, "WRITE DMA QUEUED FUA EXT" },
2246		{ ATA_CMD_FPDMA_READ,		"READ FPDMA QUEUED" },
2247		{ ATA_CMD_FPDMA_WRITE,		"WRITE FPDMA QUEUED" },
2248		{ ATA_CMD_NCQ_NON_DATA,		"NCQ NON-DATA" },
2249		{ ATA_CMD_FPDMA_SEND,		"SEND FPDMA QUEUED" },
2250		{ ATA_CMD_FPDMA_RECV,		"RECEIVE FPDMA QUEUED" },
2251		{ ATA_CMD_PIO_READ,		"READ SECTOR(S)" },
2252		{ ATA_CMD_PIO_READ_EXT,		"READ SECTOR(S) EXT" },
2253		{ ATA_CMD_PIO_WRITE,		"WRITE SECTOR(S)" },
2254		{ ATA_CMD_PIO_WRITE_EXT,	"WRITE SECTOR(S) EXT" },
2255		{ ATA_CMD_READ_MULTI,		"READ MULTIPLE" },
2256		{ ATA_CMD_READ_MULTI_EXT,	"READ MULTIPLE EXT" },
2257		{ ATA_CMD_WRITE_MULTI,		"WRITE MULTIPLE" },
2258		{ ATA_CMD_WRITE_MULTI_EXT,	"WRITE MULTIPLE EXT" },
2259		{ ATA_CMD_WRITE_MULTI_FUA_EXT,	"WRITE MULTIPLE FUA EXT" },
2260		{ ATA_CMD_SET_FEATURES,		"SET FEATURES" },
2261		{ ATA_CMD_SET_MULTI,		"SET MULTIPLE MODE" },
2262		{ ATA_CMD_VERIFY,		"READ VERIFY SECTOR(S)" },
2263		{ ATA_CMD_VERIFY_EXT,		"READ VERIFY SECTOR(S) EXT" },
2264		{ ATA_CMD_WRITE_UNCORR_EXT,	"WRITE UNCORRECTABLE EXT" },
2265		{ ATA_CMD_STANDBYNOW1,		"STANDBY IMMEDIATE" },
2266		{ ATA_CMD_IDLEIMMEDIATE,	"IDLE IMMEDIATE" },
2267		{ ATA_CMD_SLEEP,		"SLEEP" },
2268		{ ATA_CMD_INIT_DEV_PARAMS,	"INITIALIZE DEVICE PARAMETERS" },
2269		{ ATA_CMD_READ_NATIVE_MAX,	"READ NATIVE MAX ADDRESS" },
2270		{ ATA_CMD_READ_NATIVE_MAX_EXT,	"READ NATIVE MAX ADDRESS EXT" },
2271		{ ATA_CMD_SET_MAX,		"SET MAX ADDRESS" },
2272		{ ATA_CMD_SET_MAX_EXT,		"SET MAX ADDRESS EXT" },
2273		{ ATA_CMD_READ_LOG_EXT,		"READ LOG EXT" },
2274		{ ATA_CMD_WRITE_LOG_EXT,	"WRITE LOG EXT" },
2275		{ ATA_CMD_READ_LOG_DMA_EXT,	"READ LOG DMA EXT" },
2276		{ ATA_CMD_WRITE_LOG_DMA_EXT,	"WRITE LOG DMA EXT" },
2277		{ ATA_CMD_TRUSTED_NONDATA,	"TRUSTED NON-DATA" },
2278		{ ATA_CMD_TRUSTED_RCV,		"TRUSTED RECEIVE" },
2279		{ ATA_CMD_TRUSTED_RCV_DMA,	"TRUSTED RECEIVE DMA" },
2280		{ ATA_CMD_TRUSTED_SND,		"TRUSTED SEND" },
2281		{ ATA_CMD_TRUSTED_SND_DMA,	"TRUSTED SEND DMA" },
2282		{ ATA_CMD_PMP_READ,		"READ BUFFER" },
2283		{ ATA_CMD_PMP_READ_DMA,		"READ BUFFER DMA" },
2284		{ ATA_CMD_PMP_WRITE,		"WRITE BUFFER" },
2285		{ ATA_CMD_PMP_WRITE_DMA,	"WRITE BUFFER DMA" },
2286		{ ATA_CMD_CONF_OVERLAY,		"DEVICE CONFIGURATION OVERLAY" },
2287		{ ATA_CMD_SEC_SET_PASS,		"SECURITY SET PASSWORD" },
2288		{ ATA_CMD_SEC_UNLOCK,		"SECURITY UNLOCK" },
2289		{ ATA_CMD_SEC_ERASE_PREP,	"SECURITY ERASE PREPARE" },
2290		{ ATA_CMD_SEC_ERASE_UNIT,	"SECURITY ERASE UNIT" },
2291		{ ATA_CMD_SEC_FREEZE_LOCK,	"SECURITY FREEZE LOCK" },
2292		{ ATA_CMD_SEC_DISABLE_PASS,	"SECURITY DISABLE PASSWORD" },
2293		{ ATA_CMD_CONFIG_STREAM,	"CONFIGURE STREAM" },
2294		{ ATA_CMD_SMART,		"SMART" },
2295		{ ATA_CMD_MEDIA_LOCK,		"DOOR LOCK" },
2296		{ ATA_CMD_MEDIA_UNLOCK,		"DOOR UNLOCK" },
2297		{ ATA_CMD_DSM,			"DATA SET MANAGEMENT" },
2298		{ ATA_CMD_CHK_MED_CRD_TYP,	"CHECK MEDIA CARD TYPE" },
2299		{ ATA_CMD_CFA_REQ_EXT_ERR,	"CFA REQUEST EXTENDED ERROR" },
2300		{ ATA_CMD_CFA_WRITE_NE,		"CFA WRITE SECTORS WITHOUT ERASE" },
2301		{ ATA_CMD_CFA_TRANS_SECT,	"CFA TRANSLATE SECTOR" },
2302		{ ATA_CMD_CFA_ERASE,		"CFA ERASE SECTORS" },
2303		{ ATA_CMD_CFA_WRITE_MULT_NE,	"CFA WRITE MULTIPLE WITHOUT ERASE" },
2304		{ ATA_CMD_REQ_SENSE_DATA,	"REQUEST SENSE DATA EXT" },
2305		{ ATA_CMD_SANITIZE_DEVICE,	"SANITIZE DEVICE" },
2306		{ ATA_CMD_ZAC_MGMT_IN,		"ZAC MANAGEMENT IN" },
2307		{ ATA_CMD_ZAC_MGMT_OUT,		"ZAC MANAGEMENT OUT" },
2308		{ ATA_CMD_READ_LONG,		"READ LONG (with retries)" },
2309		{ ATA_CMD_READ_LONG_ONCE,	"READ LONG (without retries)" },
2310		{ ATA_CMD_WRITE_LONG,		"WRITE LONG (with retries)" },
2311		{ ATA_CMD_WRITE_LONG_ONCE,	"WRITE LONG (without retries)" },
2312		{ ATA_CMD_RESTORE,		"RECALIBRATE" },
2313		{ 0,				NULL } /* terminate list */
2314	};
2315
2316	unsigned int i;
2317	for (i = 0; cmd_descr[i].text; i++)
2318		if (cmd_descr[i].command == command)
2319			return cmd_descr[i].text;
2320#endif
2321
2322	return "unknown";
2323}
2324EXPORT_SYMBOL_GPL(ata_get_cmd_name);
2325
2326/**
2327 *	ata_eh_link_report - report error handling to user
2328 *	@link: ATA link EH is going on
2329 *
2330 *	Report EH to user.
2331 *
2332 *	LOCKING:
2333 *	None.
2334 */
2335static void ata_eh_link_report(struct ata_link *link)
2336{
2337	struct ata_port *ap = link->ap;
2338	struct ata_eh_context *ehc = &link->eh_context;
2339	struct ata_queued_cmd *qc;
2340	const char *frozen, *desc;
2341	char tries_buf[16] = "";
2342	int tag, nr_failed = 0;
2343
2344	if (ehc->i.flags & ATA_EHI_QUIET)
2345		return;
2346
2347	desc = NULL;
2348	if (ehc->i.desc[0] != '\0')
2349		desc = ehc->i.desc;
2350
2351	ata_qc_for_each_raw(ap, qc, tag) {
2352		if (!(qc->flags & ATA_QCFLAG_EH) ||
2353		    ata_dev_phys_link(qc->dev) != link ||
2354		    ((qc->flags & ATA_QCFLAG_QUIET) &&
2355		     qc->err_mask == AC_ERR_DEV))
2356			continue;
2357		if (qc->flags & ATA_QCFLAG_SENSE_VALID && !qc->err_mask)
2358			continue;
2359
2360		nr_failed++;
2361	}
2362
2363	if (!nr_failed && !ehc->i.err_mask)
2364		return;
2365
2366	frozen = "";
2367	if (ata_port_is_frozen(ap))
2368		frozen = " frozen";
2369
2370	if (ap->eh_tries < ATA_EH_MAX_TRIES)
2371		snprintf(tries_buf, sizeof(tries_buf), " t%d",
2372			 ap->eh_tries);
2373
2374	if (ehc->i.dev) {
2375		ata_dev_err(ehc->i.dev, "exception Emask 0x%x "
2376			    "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2377			    ehc->i.err_mask, link->sactive, ehc->i.serror,
2378			    ehc->i.action, frozen, tries_buf);
2379		if (desc)
2380			ata_dev_err(ehc->i.dev, "%s\n", desc);
2381	} else {
2382		ata_link_err(link, "exception Emask 0x%x "
2383			     "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2384			     ehc->i.err_mask, link->sactive, ehc->i.serror,
2385			     ehc->i.action, frozen, tries_buf);
2386		if (desc)
2387			ata_link_err(link, "%s\n", desc);
2388	}
2389
2390#ifdef CONFIG_ATA_VERBOSE_ERROR
2391	if (ehc->i.serror)
2392		ata_link_err(link,
2393		  "SError: { %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s}\n",
2394		  ehc->i.serror & SERR_DATA_RECOVERED ? "RecovData " : "",
2395		  ehc->i.serror & SERR_COMM_RECOVERED ? "RecovComm " : "",
2396		  ehc->i.serror & SERR_DATA ? "UnrecovData " : "",
2397		  ehc->i.serror & SERR_PERSISTENT ? "Persist " : "",
2398		  ehc->i.serror & SERR_PROTOCOL ? "Proto " : "",
2399		  ehc->i.serror & SERR_INTERNAL ? "HostInt " : "",
2400		  ehc->i.serror & SERR_PHYRDY_CHG ? "PHYRdyChg " : "",
2401		  ehc->i.serror & SERR_PHY_INT_ERR ? "PHYInt " : "",
2402		  ehc->i.serror & SERR_COMM_WAKE ? "CommWake " : "",
2403		  ehc->i.serror & SERR_10B_8B_ERR ? "10B8B " : "",
2404		  ehc->i.serror & SERR_DISPARITY ? "Dispar " : "",
2405		  ehc->i.serror & SERR_CRC ? "BadCRC " : "",
2406		  ehc->i.serror & SERR_HANDSHAKE ? "Handshk " : "",
2407		  ehc->i.serror & SERR_LINK_SEQ_ERR ? "LinkSeq " : "",
2408		  ehc->i.serror & SERR_TRANS_ST_ERROR ? "TrStaTrns " : "",
2409		  ehc->i.serror & SERR_UNRECOG_FIS ? "UnrecFIS " : "",
2410		  ehc->i.serror & SERR_DEV_XCHG ? "DevExch " : "");
2411#endif
2412
2413	ata_qc_for_each_raw(ap, qc, tag) {
2414		struct ata_taskfile *cmd = &qc->tf, *res = &qc->result_tf;
2415		char data_buf[20] = "";
2416		char cdb_buf[70] = "";
2417
2418		if (!(qc->flags & ATA_QCFLAG_EH) ||
2419		    ata_dev_phys_link(qc->dev) != link || !qc->err_mask)
2420			continue;
2421
2422		if (qc->dma_dir != DMA_NONE) {
2423			static const char *dma_str[] = {
2424				[DMA_BIDIRECTIONAL]	= "bidi",
2425				[DMA_TO_DEVICE]		= "out",
2426				[DMA_FROM_DEVICE]	= "in",
2427			};
2428			const char *prot_str = NULL;
2429
2430			switch (qc->tf.protocol) {
2431			case ATA_PROT_UNKNOWN:
2432				prot_str = "unknown";
2433				break;
2434			case ATA_PROT_NODATA:
2435				prot_str = "nodata";
2436				break;
2437			case ATA_PROT_PIO:
2438				prot_str = "pio";
2439				break;
2440			case ATA_PROT_DMA:
2441				prot_str = "dma";
2442				break;
2443			case ATA_PROT_NCQ:
2444				prot_str = "ncq dma";
2445				break;
2446			case ATA_PROT_NCQ_NODATA:
2447				prot_str = "ncq nodata";
2448				break;
2449			case ATAPI_PROT_NODATA:
2450				prot_str = "nodata";
2451				break;
2452			case ATAPI_PROT_PIO:
2453				prot_str = "pio";
2454				break;
2455			case ATAPI_PROT_DMA:
2456				prot_str = "dma";
2457				break;
2458			}
2459			snprintf(data_buf, sizeof(data_buf), " %s %u %s",
2460				 prot_str, qc->nbytes, dma_str[qc->dma_dir]);
2461		}
2462
2463		if (ata_is_atapi(qc->tf.protocol)) {
2464			const u8 *cdb = qc->cdb;
2465			size_t cdb_len = qc->dev->cdb_len;
2466
2467			if (qc->scsicmd) {
2468				cdb = qc->scsicmd->cmnd;
2469				cdb_len = qc->scsicmd->cmd_len;
2470			}
2471			__scsi_format_command(cdb_buf, sizeof(cdb_buf),
2472					      cdb, cdb_len);
2473		} else
2474			ata_dev_err(qc->dev, "failed command: %s\n",
2475				    ata_get_cmd_name(cmd->command));
2476
2477		ata_dev_err(qc->dev,
2478			"cmd %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2479			"tag %d%s\n         %s"
2480			"res %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2481			"Emask 0x%x (%s)%s\n",
2482			cmd->command, cmd->feature, cmd->nsect,
2483			cmd->lbal, cmd->lbam, cmd->lbah,
2484			cmd->hob_feature, cmd->hob_nsect,
2485			cmd->hob_lbal, cmd->hob_lbam, cmd->hob_lbah,
2486			cmd->device, qc->tag, data_buf, cdb_buf,
2487			res->status, res->error, res->nsect,
2488			res->lbal, res->lbam, res->lbah,
2489			res->hob_feature, res->hob_nsect,
2490			res->hob_lbal, res->hob_lbam, res->hob_lbah,
2491			res->device, qc->err_mask, ata_err_string(qc->err_mask),
2492			qc->err_mask & AC_ERR_NCQ ? " <F>" : "");
2493
2494#ifdef CONFIG_ATA_VERBOSE_ERROR
2495		if (res->status & (ATA_BUSY | ATA_DRDY | ATA_DF | ATA_DRQ |
2496				   ATA_SENSE | ATA_ERR)) {
2497			if (res->status & ATA_BUSY)
2498				ata_dev_err(qc->dev, "status: { Busy }\n");
2499			else
2500				ata_dev_err(qc->dev, "status: { %s%s%s%s%s}\n",
2501				  res->status & ATA_DRDY ? "DRDY " : "",
2502				  res->status & ATA_DF ? "DF " : "",
2503				  res->status & ATA_DRQ ? "DRQ " : "",
2504				  res->status & ATA_SENSE ? "SENSE " : "",
2505				  res->status & ATA_ERR ? "ERR " : "");
2506		}
2507
2508		if (cmd->command != ATA_CMD_PACKET &&
2509		    (res->error & (ATA_ICRC | ATA_UNC | ATA_AMNF | ATA_IDNF |
2510				   ATA_ABORTED)))
2511			ata_dev_err(qc->dev, "error: { %s%s%s%s%s}\n",
2512				    res->error & ATA_ICRC ? "ICRC " : "",
2513				    res->error & ATA_UNC ? "UNC " : "",
2514				    res->error & ATA_AMNF ? "AMNF " : "",
2515				    res->error & ATA_IDNF ? "IDNF " : "",
2516				    res->error & ATA_ABORTED ? "ABRT " : "");
2517#endif
2518	}
2519}
2520
2521/**
2522 *	ata_eh_report - report error handling to user
2523 *	@ap: ATA port to report EH about
2524 *
2525 *	Report EH to user.
2526 *
2527 *	LOCKING:
2528 *	None.
2529 */
2530void ata_eh_report(struct ata_port *ap)
2531{
2532	struct ata_link *link;
2533
2534	ata_for_each_link(link, ap, HOST_FIRST)
2535		ata_eh_link_report(link);
2536}
2537
2538static int ata_do_reset(struct ata_link *link, ata_reset_fn_t reset,
2539			unsigned int *classes, unsigned long deadline,
2540			bool clear_classes)
2541{
2542	struct ata_device *dev;
2543
2544	if (clear_classes)
2545		ata_for_each_dev(dev, link, ALL)
2546			classes[dev->devno] = ATA_DEV_UNKNOWN;
2547
2548	return reset(link, classes, deadline);
2549}
2550
2551static int ata_eh_followup_srst_needed(struct ata_link *link, int rc)
2552{
2553	if ((link->flags & ATA_LFLAG_NO_SRST) || ata_link_offline(link))
2554		return 0;
2555	if (rc == -EAGAIN)
2556		return 1;
2557	if (sata_pmp_supported(link->ap) && ata_is_host_link(link))
2558		return 1;
2559	return 0;
2560}
2561
2562int ata_eh_reset(struct ata_link *link, int classify,
2563		 ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
2564		 ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
2565{
2566	struct ata_port *ap = link->ap;
2567	struct ata_link *slave = ap->slave_link;
2568	struct ata_eh_context *ehc = &link->eh_context;
2569	struct ata_eh_context *sehc = slave ? &slave->eh_context : NULL;
2570	unsigned int *classes = ehc->classes;
2571	unsigned int lflags = link->flags;
2572	int verbose = !(ehc->i.flags & ATA_EHI_QUIET);
2573	int max_tries = 0, try = 0;
2574	struct ata_link *failed_link;
2575	struct ata_device *dev;
2576	unsigned long deadline, now;
2577	ata_reset_fn_t reset;
2578	unsigned long flags;
2579	u32 sstatus;
2580	int nr_unknown, rc;
2581
2582	/*
2583	 * Prepare to reset
2584	 */
2585	while (ata_eh_reset_timeouts[max_tries] != UINT_MAX)
2586		max_tries++;
2587	if (link->flags & ATA_LFLAG_RST_ONCE)
2588		max_tries = 1;
2589	if (link->flags & ATA_LFLAG_NO_HRST)
2590		hardreset = NULL;
2591	if (link->flags & ATA_LFLAG_NO_SRST)
2592		softreset = NULL;
2593
2594	/* make sure each reset attempt is at least COOL_DOWN apart */
2595	if (ehc->i.flags & ATA_EHI_DID_RESET) {
2596		now = jiffies;
2597		WARN_ON(time_after(ehc->last_reset, now));
2598		deadline = ata_deadline(ehc->last_reset,
2599					ATA_EH_RESET_COOL_DOWN);
2600		if (time_before(now, deadline))
2601			schedule_timeout_uninterruptible(deadline - now);
2602	}
2603
2604	spin_lock_irqsave(ap->lock, flags);
2605	ap->pflags |= ATA_PFLAG_RESETTING;
2606	spin_unlock_irqrestore(ap->lock, flags);
2607
2608	ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2609
2610	ata_for_each_dev(dev, link, ALL) {
2611		/* If we issue an SRST then an ATA drive (not ATAPI)
2612		 * may change configuration and be in PIO0 timing. If
2613		 * we do a hard reset (or are coming from power on)
2614		 * this is true for ATA or ATAPI. Until we've set a
2615		 * suitable controller mode we should not touch the
2616		 * bus as we may be talking too fast.
2617		 */
2618		dev->pio_mode = XFER_PIO_0;
2619		dev->dma_mode = 0xff;
2620
2621		/* If the controller has a pio mode setup function
2622		 * then use it to set the chipset to rights. Don't
2623		 * touch the DMA setup as that will be dealt with when
2624		 * configuring devices.
2625		 */
2626		if (ap->ops->set_piomode)
2627			ap->ops->set_piomode(ap, dev);
2628	}
2629
2630	/* prefer hardreset */
2631	reset = NULL;
2632	ehc->i.action &= ~ATA_EH_RESET;
2633	if (hardreset) {
2634		reset = hardreset;
2635		ehc->i.action |= ATA_EH_HARDRESET;
2636	} else if (softreset) {
2637		reset = softreset;
2638		ehc->i.action |= ATA_EH_SOFTRESET;
2639	}
2640
2641	if (prereset) {
2642		unsigned long deadline = ata_deadline(jiffies,
2643						      ATA_EH_PRERESET_TIMEOUT);
2644
2645		if (slave) {
2646			sehc->i.action &= ~ATA_EH_RESET;
2647			sehc->i.action |= ehc->i.action;
2648		}
2649
2650		rc = prereset(link, deadline);
2651
2652		/* If present, do prereset on slave link too.  Reset
2653		 * is skipped iff both master and slave links report
2654		 * -ENOENT or clear ATA_EH_RESET.
2655		 */
2656		if (slave && (rc == 0 || rc == -ENOENT)) {
2657			int tmp;
2658
2659			tmp = prereset(slave, deadline);
2660			if (tmp != -ENOENT)
2661				rc = tmp;
2662
2663			ehc->i.action |= sehc->i.action;
2664		}
2665
2666		if (rc) {
2667			if (rc == -ENOENT) {
2668				ata_link_dbg(link, "port disabled--ignoring\n");
2669				ehc->i.action &= ~ATA_EH_RESET;
2670
2671				ata_for_each_dev(dev, link, ALL)
2672					classes[dev->devno] = ATA_DEV_NONE;
2673
2674				rc = 0;
2675			} else
2676				ata_link_err(link,
2677					     "prereset failed (errno=%d)\n",
2678					     rc);
2679			goto out;
2680		}
2681
2682		/* prereset() might have cleared ATA_EH_RESET.  If so,
2683		 * bang classes, thaw and return.
2684		 */
2685		if (reset && !(ehc->i.action & ATA_EH_RESET)) {
2686			ata_for_each_dev(dev, link, ALL)
2687				classes[dev->devno] = ATA_DEV_NONE;
2688			if (ata_port_is_frozen(ap) && ata_is_host_link(link))
2689				ata_eh_thaw_port(ap);
2690			rc = 0;
2691			goto out;
2692		}
2693	}
2694
2695 retry:
2696	/*
2697	 * Perform reset
2698	 */
2699	if (ata_is_host_link(link))
2700		ata_eh_freeze_port(ap);
2701
2702	deadline = ata_deadline(jiffies, ata_eh_reset_timeouts[try++]);
2703
2704	if (reset) {
2705		if (verbose)
2706			ata_link_info(link, "%s resetting link\n",
2707				      reset == softreset ? "soft" : "hard");
2708
2709		/* mark that this EH session started with reset */
2710		ehc->last_reset = jiffies;
2711		if (reset == hardreset) {
2712			ehc->i.flags |= ATA_EHI_DID_HARDRESET;
2713			trace_ata_link_hardreset_begin(link, classes, deadline);
2714		} else {
2715			ehc->i.flags |= ATA_EHI_DID_SOFTRESET;
2716			trace_ata_link_softreset_begin(link, classes, deadline);
2717		}
2718
2719		rc = ata_do_reset(link, reset, classes, deadline, true);
2720		if (reset == hardreset)
2721			trace_ata_link_hardreset_end(link, classes, rc);
2722		else
2723			trace_ata_link_softreset_end(link, classes, rc);
2724		if (rc && rc != -EAGAIN) {
2725			failed_link = link;
2726			goto fail;
2727		}
2728
2729		/* hardreset slave link if existent */
2730		if (slave && reset == hardreset) {
2731			int tmp;
2732
2733			if (verbose)
2734				ata_link_info(slave, "hard resetting link\n");
2735
2736			ata_eh_about_to_do(slave, NULL, ATA_EH_RESET);
2737			trace_ata_slave_hardreset_begin(slave, classes,
2738							deadline);
2739			tmp = ata_do_reset(slave, reset, classes, deadline,
2740					   false);
2741			trace_ata_slave_hardreset_end(slave, classes, tmp);
2742			switch (tmp) {
2743			case -EAGAIN:
2744				rc = -EAGAIN;
2745				break;
2746			case 0:
2747				break;
2748			default:
2749				failed_link = slave;
2750				rc = tmp;
2751				goto fail;
2752			}
2753		}
2754
2755		/* perform follow-up SRST if necessary */
2756		if (reset == hardreset &&
2757		    ata_eh_followup_srst_needed(link, rc)) {
2758			reset = softreset;
2759
2760			if (!reset) {
2761				ata_link_err(link,
2762	     "follow-up softreset required but no softreset available\n");
2763				failed_link = link;
2764				rc = -EINVAL;
2765				goto fail;
2766			}
2767
2768			ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2769			trace_ata_link_softreset_begin(link, classes, deadline);
2770			rc = ata_do_reset(link, reset, classes, deadline, true);
2771			trace_ata_link_softreset_end(link, classes, rc);
2772			if (rc) {
2773				failed_link = link;
2774				goto fail;
2775			}
2776		}
2777	} else {
2778		if (verbose)
2779			ata_link_info(link,
2780	"no reset method available, skipping reset\n");
2781		if (!(lflags & ATA_LFLAG_ASSUME_CLASS))
2782			lflags |= ATA_LFLAG_ASSUME_ATA;
2783	}
2784
2785	/*
2786	 * Post-reset processing
2787	 */
2788	ata_for_each_dev(dev, link, ALL) {
2789		/* After the reset, the device state is PIO 0 and the
2790		 * controller state is undefined.  Reset also wakes up
2791		 * drives from sleeping mode.
2792		 */
2793		dev->pio_mode = XFER_PIO_0;
2794		dev->flags &= ~ATA_DFLAG_SLEEPING;
2795
2796		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
2797			continue;
2798
2799		/* apply class override */
2800		if (lflags & ATA_LFLAG_ASSUME_ATA)
2801			classes[dev->devno] = ATA_DEV_ATA;
2802		else if (lflags & ATA_LFLAG_ASSUME_SEMB)
2803			classes[dev->devno] = ATA_DEV_SEMB_UNSUP;
2804	}
2805
2806	/* record current link speed */
2807	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0)
2808		link->sata_spd = (sstatus >> 4) & 0xf;
2809	if (slave && sata_scr_read(slave, SCR_STATUS, &sstatus) == 0)
2810		slave->sata_spd = (sstatus >> 4) & 0xf;
2811
2812	/* thaw the port */
2813	if (ata_is_host_link(link))
2814		ata_eh_thaw_port(ap);
2815
2816	/* postreset() should clear hardware SError.  Although SError
2817	 * is cleared during link resume, clearing SError here is
2818	 * necessary as some PHYs raise hotplug events after SRST.
2819	 * This introduces race condition where hotplug occurs between
2820	 * reset and here.  This race is mediated by cross checking
2821	 * link onlineness and classification result later.
2822	 */
2823	if (postreset) {
2824		postreset(link, classes);
2825		trace_ata_link_postreset(link, classes, rc);
2826		if (slave) {
2827			postreset(slave, classes);
2828			trace_ata_slave_postreset(slave, classes, rc);
2829		}
2830	}
2831
2832	/* clear cached SError */
 
 
 
 
 
 
2833	spin_lock_irqsave(link->ap->lock, flags);
2834	link->eh_info.serror = 0;
2835	if (slave)
2836		slave->eh_info.serror = 0;
 
2837	spin_unlock_irqrestore(link->ap->lock, flags);
2838
 
 
 
2839	/*
2840	 * Make sure onlineness and classification result correspond.
2841	 * Hotplug could have happened during reset and some
2842	 * controllers fail to wait while a drive is spinning up after
2843	 * being hotplugged causing misdetection.  By cross checking
2844	 * link on/offlineness and classification result, those
2845	 * conditions can be reliably detected and retried.
2846	 */
2847	nr_unknown = 0;
2848	ata_for_each_dev(dev, link, ALL) {
2849		if (ata_phys_link_online(ata_dev_phys_link(dev))) {
2850			if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2851				ata_dev_dbg(dev, "link online but device misclassified\n");
2852				classes[dev->devno] = ATA_DEV_NONE;
2853				nr_unknown++;
2854			}
2855		} else if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
2856			if (ata_class_enabled(classes[dev->devno]))
2857				ata_dev_dbg(dev,
2858					    "link offline, clearing class %d to NONE\n",
2859					    classes[dev->devno]);
2860			classes[dev->devno] = ATA_DEV_NONE;
2861		} else if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2862			ata_dev_dbg(dev,
2863				    "link status unknown, clearing UNKNOWN to NONE\n");
2864			classes[dev->devno] = ATA_DEV_NONE;
2865		}
2866	}
2867
2868	if (classify && nr_unknown) {
2869		if (try < max_tries) {
2870			ata_link_warn(link,
2871				      "link online but %d devices misclassified, retrying\n",
2872				      nr_unknown);
2873			failed_link = link;
2874			rc = -EAGAIN;
2875			goto fail;
2876		}
2877		ata_link_warn(link,
2878			      "link online but %d devices misclassified, "
2879			      "device detection might fail\n", nr_unknown);
2880	}
2881
2882	/* reset successful, schedule revalidation */
2883	ata_eh_done(link, NULL, ATA_EH_RESET);
2884	if (slave)
2885		ata_eh_done(slave, NULL, ATA_EH_RESET);
2886	ehc->last_reset = jiffies;		/* update to completion time */
2887	ehc->i.action |= ATA_EH_REVALIDATE;
2888	link->lpm_policy = ATA_LPM_UNKNOWN;	/* reset LPM state */
2889
2890	rc = 0;
2891 out:
2892	/* clear hotplug flag */
2893	ehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2894	if (slave)
2895		sehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2896
2897	spin_lock_irqsave(ap->lock, flags);
2898	ap->pflags &= ~ATA_PFLAG_RESETTING;
2899	spin_unlock_irqrestore(ap->lock, flags);
2900
2901	return rc;
2902
2903 fail:
2904	/* if SCR isn't accessible on a fan-out port, PMP needs to be reset */
2905	if (!ata_is_host_link(link) &&
2906	    sata_scr_read(link, SCR_STATUS, &sstatus))
2907		rc = -ERESTART;
2908
2909	if (try >= max_tries) {
2910		/*
2911		 * Thaw host port even if reset failed, so that the port
2912		 * can be retried on the next phy event.  This risks
2913		 * repeated EH runs but seems to be a better tradeoff than
2914		 * shutting down a port after a botched hotplug attempt.
2915		 */
2916		if (ata_is_host_link(link))
2917			ata_eh_thaw_port(ap);
2918		ata_link_warn(link, "%s failed\n",
2919			      reset == hardreset ? "hardreset" : "softreset");
2920		goto out;
2921	}
2922
2923	now = jiffies;
2924	if (time_before(now, deadline)) {
2925		unsigned long delta = deadline - now;
2926
2927		ata_link_warn(failed_link,
2928			"reset failed (errno=%d), retrying in %u secs\n",
2929			rc, DIV_ROUND_UP(jiffies_to_msecs(delta), 1000));
2930
2931		ata_eh_release(ap);
2932		while (delta)
2933			delta = schedule_timeout_uninterruptible(delta);
2934		ata_eh_acquire(ap);
2935	}
2936
2937	/*
2938	 * While disks spinup behind PMP, some controllers fail sending SRST.
2939	 * They need to be reset - as well as the PMP - before retrying.
2940	 */
2941	if (rc == -ERESTART) {
2942		if (ata_is_host_link(link))
2943			ata_eh_thaw_port(ap);
2944		goto out;
2945	}
2946
2947	if (try == max_tries - 1) {
2948		sata_down_spd_limit(link, 0);
2949		if (slave)
2950			sata_down_spd_limit(slave, 0);
2951	} else if (rc == -EPIPE)
2952		sata_down_spd_limit(failed_link, 0);
2953
2954	if (hardreset)
2955		reset = hardreset;
2956	goto retry;
2957}
2958
2959static inline void ata_eh_pull_park_action(struct ata_port *ap)
2960{
2961	struct ata_link *link;
2962	struct ata_device *dev;
2963	unsigned long flags;
2964
2965	/*
2966	 * This function can be thought of as an extended version of
2967	 * ata_eh_about_to_do() specially crafted to accommodate the
2968	 * requirements of ATA_EH_PARK handling. Since the EH thread
2969	 * does not leave the do {} while () loop in ata_eh_recover as
2970	 * long as the timeout for a park request to *one* device on
2971	 * the port has not expired, and since we still want to pick
2972	 * up park requests to other devices on the same port or
2973	 * timeout updates for the same device, we have to pull
2974	 * ATA_EH_PARK actions from eh_info into eh_context.i
2975	 * ourselves at the beginning of each pass over the loop.
2976	 *
2977	 * Additionally, all write accesses to &ap->park_req_pending
2978	 * through reinit_completion() (see below) or complete_all()
2979	 * (see ata_scsi_park_store()) are protected by the host lock.
2980	 * As a result we have that park_req_pending.done is zero on
2981	 * exit from this function, i.e. when ATA_EH_PARK actions for
2982	 * *all* devices on port ap have been pulled into the
2983	 * respective eh_context structs. If, and only if,
2984	 * park_req_pending.done is non-zero by the time we reach
2985	 * wait_for_completion_timeout(), another ATA_EH_PARK action
2986	 * has been scheduled for at least one of the devices on port
2987	 * ap and we have to cycle over the do {} while () loop in
2988	 * ata_eh_recover() again.
2989	 */
2990
2991	spin_lock_irqsave(ap->lock, flags);
2992	reinit_completion(&ap->park_req_pending);
2993	ata_for_each_link(link, ap, EDGE) {
2994		ata_for_each_dev(dev, link, ALL) {
2995			struct ata_eh_info *ehi = &link->eh_info;
2996
2997			link->eh_context.i.dev_action[dev->devno] |=
2998				ehi->dev_action[dev->devno] & ATA_EH_PARK;
2999			ata_eh_clear_action(link, dev, ehi, ATA_EH_PARK);
3000		}
3001	}
3002	spin_unlock_irqrestore(ap->lock, flags);
3003}
3004
3005static void ata_eh_park_issue_cmd(struct ata_device *dev, int park)
3006{
3007	struct ata_eh_context *ehc = &dev->link->eh_context;
3008	struct ata_taskfile tf;
3009	unsigned int err_mask;
3010
3011	ata_tf_init(dev, &tf);
3012	if (park) {
3013		ehc->unloaded_mask |= 1 << dev->devno;
3014		tf.command = ATA_CMD_IDLEIMMEDIATE;
3015		tf.feature = 0x44;
3016		tf.lbal = 0x4c;
3017		tf.lbam = 0x4e;
3018		tf.lbah = 0x55;
3019	} else {
3020		ehc->unloaded_mask &= ~(1 << dev->devno);
3021		tf.command = ATA_CMD_CHK_POWER;
3022	}
3023
3024	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
3025	tf.protocol = ATA_PROT_NODATA;
3026	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
3027	if (park && (err_mask || tf.lbal != 0xc4)) {
3028		ata_dev_err(dev, "head unload failed!\n");
3029		ehc->unloaded_mask &= ~(1 << dev->devno);
3030	}
3031}
3032
3033static int ata_eh_revalidate_and_attach(struct ata_link *link,
3034					struct ata_device **r_failed_dev)
3035{
3036	struct ata_port *ap = link->ap;
3037	struct ata_eh_context *ehc = &link->eh_context;
3038	struct ata_device *dev;
3039	unsigned int new_mask = 0;
3040	unsigned long flags;
3041	int rc = 0;
3042
3043	/* For PATA drive side cable detection to work, IDENTIFY must
3044	 * be done backwards such that PDIAG- is released by the slave
3045	 * device before the master device is identified.
3046	 */
3047	ata_for_each_dev(dev, link, ALL_REVERSE) {
3048		unsigned int action = ata_eh_dev_action(dev);
3049		unsigned int readid_flags = 0;
3050
3051		if (ehc->i.flags & ATA_EHI_DID_RESET)
3052			readid_flags |= ATA_READID_POSTRESET;
3053
3054		if ((action & ATA_EH_REVALIDATE) && ata_dev_enabled(dev)) {
3055			WARN_ON(dev->class == ATA_DEV_PMP);
3056
3057			/*
3058			 * The link may be in a deep sleep, wake it up.
3059			 *
3060			 * If the link is in deep sleep, ata_phys_link_offline()
3061			 * will return true, causing the revalidation to fail,
3062			 * which leads to a (potentially) needless hard reset.
3063			 *
3064			 * ata_eh_recover() will later restore the link policy
3065			 * to ap->target_lpm_policy after revalidation is done.
3066			 */
3067			if (link->lpm_policy > ATA_LPM_MAX_POWER) {
3068				rc = ata_eh_set_lpm(link, ATA_LPM_MAX_POWER,
3069						    r_failed_dev);
3070				if (rc)
3071					goto err;
3072			}
3073
3074			if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
3075				rc = -EIO;
3076				goto err;
3077			}
3078
3079			ata_eh_about_to_do(link, dev, ATA_EH_REVALIDATE);
3080			rc = ata_dev_revalidate(dev, ehc->classes[dev->devno],
3081						readid_flags);
3082			if (rc)
3083				goto err;
3084
3085			ata_eh_done(link, dev, ATA_EH_REVALIDATE);
3086
3087			/* Configuration may have changed, reconfigure
3088			 * transfer mode.
3089			 */
3090			ehc->i.flags |= ATA_EHI_SETMODE;
3091
3092			/* schedule the scsi_rescan_device() here */
3093			schedule_delayed_work(&ap->scsi_rescan_task, 0);
3094		} else if (dev->class == ATA_DEV_UNKNOWN &&
3095			   ehc->tries[dev->devno] &&
3096			   ata_class_enabled(ehc->classes[dev->devno])) {
3097			/* Temporarily set dev->class, it will be
3098			 * permanently set once all configurations are
3099			 * complete.  This is necessary because new
3100			 * device configuration is done in two
3101			 * separate loops.
3102			 */
3103			dev->class = ehc->classes[dev->devno];
3104
3105			if (dev->class == ATA_DEV_PMP)
3106				rc = sata_pmp_attach(dev);
3107			else
3108				rc = ata_dev_read_id(dev, &dev->class,
3109						     readid_flags, dev->id);
3110
3111			/* read_id might have changed class, store and reset */
3112			ehc->classes[dev->devno] = dev->class;
3113			dev->class = ATA_DEV_UNKNOWN;
3114
3115			switch (rc) {
3116			case 0:
3117				/* clear error info accumulated during probe */
3118				ata_ering_clear(&dev->ering);
3119				new_mask |= 1 << dev->devno;
3120				break;
3121			case -ENOENT:
3122				/* IDENTIFY was issued to non-existent
3123				 * device.  No need to reset.  Just
3124				 * thaw and ignore the device.
3125				 */
3126				ata_eh_thaw_port(ap);
3127				break;
3128			default:
3129				goto err;
3130			}
3131		}
3132	}
3133
3134	/* PDIAG- should have been released, ask cable type if post-reset */
3135	if ((ehc->i.flags & ATA_EHI_DID_RESET) && ata_is_host_link(link)) {
3136		if (ap->ops->cable_detect)
3137			ap->cbl = ap->ops->cable_detect(ap);
3138		ata_force_cbl(ap);
3139	}
3140
3141	/* Configure new devices forward such that user doesn't see
3142	 * device detection messages backwards.
3143	 */
3144	ata_for_each_dev(dev, link, ALL) {
3145		if (!(new_mask & (1 << dev->devno)))
3146			continue;
3147
3148		dev->class = ehc->classes[dev->devno];
3149
3150		if (dev->class == ATA_DEV_PMP)
3151			continue;
3152
3153		ehc->i.flags |= ATA_EHI_PRINTINFO;
3154		rc = ata_dev_configure(dev);
3155		ehc->i.flags &= ~ATA_EHI_PRINTINFO;
3156		if (rc) {
3157			dev->class = ATA_DEV_UNKNOWN;
3158			goto err;
3159		}
3160
3161		spin_lock_irqsave(ap->lock, flags);
3162		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
3163		spin_unlock_irqrestore(ap->lock, flags);
3164
3165		/* new device discovered, configure xfermode */
3166		ehc->i.flags |= ATA_EHI_SETMODE;
3167	}
3168
3169	return 0;
3170
3171 err:
3172	*r_failed_dev = dev;
3173	return rc;
3174}
3175
3176/**
3177 *	ata_set_mode - Program timings and issue SET FEATURES - XFER
3178 *	@link: link on which timings will be programmed
3179 *	@r_failed_dev: out parameter for failed device
3180 *
3181 *	Set ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3182 *	ata_set_mode() fails, pointer to the failing device is
3183 *	returned in @r_failed_dev.
3184 *
3185 *	LOCKING:
3186 *	PCI/etc. bus probe sem.
3187 *
3188 *	RETURNS:
3189 *	0 on success, negative errno otherwise
3190 */
3191int ata_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3192{
3193	struct ata_port *ap = link->ap;
3194	struct ata_device *dev;
3195	int rc;
3196
3197	/* if data transfer is verified, clear DUBIOUS_XFER on ering top */
3198	ata_for_each_dev(dev, link, ENABLED) {
3199		if (!(dev->flags & ATA_DFLAG_DUBIOUS_XFER)) {
3200			struct ata_ering_entry *ent;
3201
3202			ent = ata_ering_top(&dev->ering);
3203			if (ent)
3204				ent->eflags &= ~ATA_EFLAG_DUBIOUS_XFER;
3205		}
3206	}
3207
3208	/* has private set_mode? */
3209	if (ap->ops->set_mode)
3210		rc = ap->ops->set_mode(link, r_failed_dev);
3211	else
3212		rc = ata_do_set_mode(link, r_failed_dev);
3213
3214	/* if transfer mode has changed, set DUBIOUS_XFER on device */
3215	ata_for_each_dev(dev, link, ENABLED) {
3216		struct ata_eh_context *ehc = &link->eh_context;
3217		u8 saved_xfer_mode = ehc->saved_xfer_mode[dev->devno];
3218		u8 saved_ncq = !!(ehc->saved_ncq_enabled & (1 << dev->devno));
3219
3220		if (dev->xfer_mode != saved_xfer_mode ||
3221		    ata_ncq_enabled(dev) != saved_ncq)
3222			dev->flags |= ATA_DFLAG_DUBIOUS_XFER;
3223	}
3224
3225	return rc;
3226}
3227
3228/**
3229 *	atapi_eh_clear_ua - Clear ATAPI UNIT ATTENTION after reset
3230 *	@dev: ATAPI device to clear UA for
3231 *
3232 *	Resets and other operations can make an ATAPI device raise
3233 *	UNIT ATTENTION which causes the next operation to fail.  This
3234 *	function clears UA.
3235 *
3236 *	LOCKING:
3237 *	EH context (may sleep).
3238 *
3239 *	RETURNS:
3240 *	0 on success, -errno on failure.
3241 */
3242static int atapi_eh_clear_ua(struct ata_device *dev)
3243{
3244	int i;
3245
3246	for (i = 0; i < ATA_EH_UA_TRIES; i++) {
3247		u8 *sense_buffer = dev->link->ap->sector_buf;
3248		u8 sense_key = 0;
3249		unsigned int err_mask;
3250
3251		err_mask = atapi_eh_tur(dev, &sense_key);
3252		if (err_mask != 0 && err_mask != AC_ERR_DEV) {
3253			ata_dev_warn(dev,
3254				     "TEST_UNIT_READY failed (err_mask=0x%x)\n",
3255				     err_mask);
3256			return -EIO;
3257		}
3258
3259		if (!err_mask || sense_key != UNIT_ATTENTION)
3260			return 0;
3261
3262		err_mask = atapi_eh_request_sense(dev, sense_buffer, sense_key);
3263		if (err_mask) {
3264			ata_dev_warn(dev, "failed to clear "
3265				"UNIT ATTENTION (err_mask=0x%x)\n", err_mask);
3266			return -EIO;
3267		}
3268	}
3269
3270	ata_dev_warn(dev, "UNIT ATTENTION persists after %d tries\n",
3271		     ATA_EH_UA_TRIES);
3272
3273	return 0;
3274}
3275
3276/**
3277 *	ata_eh_maybe_retry_flush - Retry FLUSH if necessary
3278 *	@dev: ATA device which may need FLUSH retry
3279 *
3280 *	If @dev failed FLUSH, it needs to be reported upper layer
3281 *	immediately as it means that @dev failed to remap and already
3282 *	lost at least a sector and further FLUSH retrials won't make
3283 *	any difference to the lost sector.  However, if FLUSH failed
3284 *	for other reasons, for example transmission error, FLUSH needs
3285 *	to be retried.
3286 *
3287 *	This function determines whether FLUSH failure retry is
3288 *	necessary and performs it if so.
3289 *
3290 *	RETURNS:
3291 *	0 if EH can continue, -errno if EH needs to be repeated.
3292 */
3293static int ata_eh_maybe_retry_flush(struct ata_device *dev)
3294{
3295	struct ata_link *link = dev->link;
3296	struct ata_port *ap = link->ap;
3297	struct ata_queued_cmd *qc;
3298	struct ata_taskfile tf;
3299	unsigned int err_mask;
3300	int rc = 0;
3301
3302	/* did flush fail for this device? */
3303	if (!ata_tag_valid(link->active_tag))
3304		return 0;
3305
3306	qc = __ata_qc_from_tag(ap, link->active_tag);
3307	if (qc->dev != dev || (qc->tf.command != ATA_CMD_FLUSH_EXT &&
3308			       qc->tf.command != ATA_CMD_FLUSH))
3309		return 0;
3310
3311	/* if the device failed it, it should be reported to upper layers */
3312	if (qc->err_mask & AC_ERR_DEV)
3313		return 0;
3314
3315	/* flush failed for some other reason, give it another shot */
3316	ata_tf_init(dev, &tf);
3317
3318	tf.command = qc->tf.command;
3319	tf.flags |= ATA_TFLAG_DEVICE;
3320	tf.protocol = ATA_PROT_NODATA;
3321
3322	ata_dev_warn(dev, "retrying FLUSH 0x%x Emask 0x%x\n",
3323		       tf.command, qc->err_mask);
3324
3325	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
3326	if (!err_mask) {
3327		/*
3328		 * FLUSH is complete but there's no way to
3329		 * successfully complete a failed command from EH.
3330		 * Making sure retry is allowed at least once and
3331		 * retrying it should do the trick - whatever was in
3332		 * the cache is already on the platter and this won't
3333		 * cause infinite loop.
3334		 */
3335		qc->scsicmd->allowed = max(qc->scsicmd->allowed, 1);
3336	} else {
3337		ata_dev_warn(dev, "FLUSH failed Emask 0x%x\n",
3338			       err_mask);
3339		rc = -EIO;
3340
3341		/* if device failed it, report it to upper layers */
3342		if (err_mask & AC_ERR_DEV) {
3343			qc->err_mask |= AC_ERR_DEV;
3344			qc->result_tf = tf;
3345			if (!ata_port_is_frozen(ap))
3346				rc = 0;
3347		}
3348	}
3349	return rc;
3350}
3351
3352/**
3353 *	ata_eh_set_lpm - configure SATA interface power management
3354 *	@link: link to configure power management
3355 *	@policy: the link power management policy
3356 *	@r_failed_dev: out parameter for failed device
3357 *
3358 *	Enable SATA Interface power management.  This will enable
3359 *	Device Interface Power Management (DIPM) for min_power and
3360 *	medium_power_with_dipm policies, and then call driver specific
3361 *	callbacks for enabling Host Initiated Power management.
3362 *
3363 *	LOCKING:
3364 *	EH context.
3365 *
3366 *	RETURNS:
3367 *	0 on success, -errno on failure.
3368 */
3369static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
3370			  struct ata_device **r_failed_dev)
3371{
3372	struct ata_port *ap = ata_is_host_link(link) ? link->ap : NULL;
3373	struct ata_eh_context *ehc = &link->eh_context;
3374	struct ata_device *dev, *link_dev = NULL, *lpm_dev = NULL;
3375	enum ata_lpm_policy old_policy = link->lpm_policy;
3376	bool no_dipm = link->ap->flags & ATA_FLAG_NO_DIPM;
3377	unsigned int hints = ATA_LPM_EMPTY | ATA_LPM_HIPM;
3378	unsigned int err_mask;
3379	int rc;
3380
3381	/* if the link or host doesn't do LPM, noop */
3382	if (!IS_ENABLED(CONFIG_SATA_HOST) ||
3383	    (link->flags & ATA_LFLAG_NO_LPM) || (ap && !ap->ops->set_lpm))
3384		return 0;
3385
3386	/*
3387	 * DIPM is enabled only for MIN_POWER as some devices
3388	 * misbehave when the host NACKs transition to SLUMBER.  Order
3389	 * device and link configurations such that the host always
3390	 * allows DIPM requests.
3391	 */
3392	ata_for_each_dev(dev, link, ENABLED) {
3393		bool hipm = ata_id_has_hipm(dev->id);
3394		bool dipm = ata_id_has_dipm(dev->id) && !no_dipm;
3395
3396		/* find the first enabled and LPM enabled devices */
3397		if (!link_dev)
3398			link_dev = dev;
3399
3400		if (!lpm_dev && (hipm || dipm))
3401			lpm_dev = dev;
3402
3403		hints &= ~ATA_LPM_EMPTY;
3404		if (!hipm)
3405			hints &= ~ATA_LPM_HIPM;
3406
3407		/* disable DIPM before changing link config */
3408		if (policy < ATA_LPM_MED_POWER_WITH_DIPM && dipm) {
3409			err_mask = ata_dev_set_feature(dev,
3410					SETFEATURES_SATA_DISABLE, SATA_DIPM);
3411			if (err_mask && err_mask != AC_ERR_DEV) {
3412				ata_dev_warn(dev,
3413					     "failed to disable DIPM, Emask 0x%x\n",
3414					     err_mask);
3415				rc = -EIO;
3416				goto fail;
3417			}
3418		}
3419	}
3420
3421	if (ap) {
3422		rc = ap->ops->set_lpm(link, policy, hints);
3423		if (!rc && ap->slave_link)
3424			rc = ap->ops->set_lpm(ap->slave_link, policy, hints);
3425	} else
3426		rc = sata_pmp_set_lpm(link, policy, hints);
3427
3428	/*
3429	 * Attribute link config failure to the first (LPM) enabled
3430	 * device on the link.
3431	 */
3432	if (rc) {
3433		if (rc == -EOPNOTSUPP) {
3434			link->flags |= ATA_LFLAG_NO_LPM;
3435			return 0;
3436		}
3437		dev = lpm_dev ? lpm_dev : link_dev;
3438		goto fail;
3439	}
3440
3441	/*
3442	 * Low level driver acked the transition.  Issue DIPM command
3443	 * with the new policy set.
3444	 */
3445	link->lpm_policy = policy;
3446	if (ap && ap->slave_link)
3447		ap->slave_link->lpm_policy = policy;
3448
3449	/* host config updated, enable DIPM if transitioning to MIN_POWER */
3450	ata_for_each_dev(dev, link, ENABLED) {
3451		if (policy >= ATA_LPM_MED_POWER_WITH_DIPM && !no_dipm &&
3452		    ata_id_has_dipm(dev->id)) {
3453			err_mask = ata_dev_set_feature(dev,
3454					SETFEATURES_SATA_ENABLE, SATA_DIPM);
3455			if (err_mask && err_mask != AC_ERR_DEV) {
3456				ata_dev_warn(dev,
3457					"failed to enable DIPM, Emask 0x%x\n",
3458					err_mask);
3459				rc = -EIO;
3460				goto fail;
3461			}
3462		}
3463	}
3464
3465	link->last_lpm_change = jiffies;
3466	link->flags |= ATA_LFLAG_CHANGED;
3467
3468	return 0;
3469
3470fail:
3471	/* restore the old policy */
3472	link->lpm_policy = old_policy;
3473	if (ap && ap->slave_link)
3474		ap->slave_link->lpm_policy = old_policy;
3475
3476	/* if no device or only one more chance is left, disable LPM */
3477	if (!dev || ehc->tries[dev->devno] <= 2) {
3478		ata_link_warn(link, "disabling LPM on the link\n");
3479		link->flags |= ATA_LFLAG_NO_LPM;
3480	}
3481	if (r_failed_dev)
3482		*r_failed_dev = dev;
3483	return rc;
3484}
3485
3486int ata_link_nr_enabled(struct ata_link *link)
3487{
3488	struct ata_device *dev;
3489	int cnt = 0;
3490
3491	ata_for_each_dev(dev, link, ENABLED)
3492		cnt++;
3493	return cnt;
3494}
3495
3496static int ata_link_nr_vacant(struct ata_link *link)
3497{
3498	struct ata_device *dev;
3499	int cnt = 0;
3500
3501	ata_for_each_dev(dev, link, ALL)
3502		if (dev->class == ATA_DEV_UNKNOWN)
3503			cnt++;
3504	return cnt;
3505}
3506
3507static int ata_eh_skip_recovery(struct ata_link *link)
3508{
3509	struct ata_port *ap = link->ap;
3510	struct ata_eh_context *ehc = &link->eh_context;
3511	struct ata_device *dev;
3512
3513	/* skip disabled links */
3514	if (link->flags & ATA_LFLAG_DISABLED)
3515		return 1;
3516
3517	/* skip if explicitly requested */
3518	if (ehc->i.flags & ATA_EHI_NO_RECOVERY)
3519		return 1;
3520
3521	/* thaw frozen port and recover failed devices */
3522	if (ata_port_is_frozen(ap) || ata_link_nr_enabled(link))
3523		return 0;
3524
3525	/* reset at least once if reset is requested */
3526	if ((ehc->i.action & ATA_EH_RESET) &&
3527	    !(ehc->i.flags & ATA_EHI_DID_RESET))
3528		return 0;
3529
3530	/* skip if class codes for all vacant slots are ATA_DEV_NONE */
3531	ata_for_each_dev(dev, link, ALL) {
3532		if (dev->class == ATA_DEV_UNKNOWN &&
3533		    ehc->classes[dev->devno] != ATA_DEV_NONE)
3534			return 0;
3535	}
3536
3537	return 1;
3538}
3539
3540static int ata_count_probe_trials_cb(struct ata_ering_entry *ent, void *void_arg)
3541{
3542	u64 interval = msecs_to_jiffies(ATA_EH_PROBE_TRIAL_INTERVAL);
3543	u64 now = get_jiffies_64();
3544	int *trials = void_arg;
3545
3546	if ((ent->eflags & ATA_EFLAG_OLD_ER) ||
3547	    (ent->timestamp < now - min(now, interval)))
3548		return -1;
3549
3550	(*trials)++;
3551	return 0;
3552}
3553
3554static int ata_eh_schedule_probe(struct ata_device *dev)
3555{
3556	struct ata_eh_context *ehc = &dev->link->eh_context;
3557	struct ata_link *link = ata_dev_phys_link(dev);
3558	int trials = 0;
3559
3560	if (!(ehc->i.probe_mask & (1 << dev->devno)) ||
3561	    (ehc->did_probe_mask & (1 << dev->devno)))
3562		return 0;
3563
3564	ata_eh_detach_dev(dev);
3565	ata_dev_init(dev);
3566	ehc->did_probe_mask |= (1 << dev->devno);
3567	ehc->i.action |= ATA_EH_RESET;
3568	ehc->saved_xfer_mode[dev->devno] = 0;
3569	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
3570
3571	/* the link maybe in a deep sleep, wake it up */
3572	if (link->lpm_policy > ATA_LPM_MAX_POWER) {
3573		if (ata_is_host_link(link))
3574			link->ap->ops->set_lpm(link, ATA_LPM_MAX_POWER,
3575					       ATA_LPM_EMPTY);
3576		else
3577			sata_pmp_set_lpm(link, ATA_LPM_MAX_POWER,
3578					 ATA_LPM_EMPTY);
3579	}
3580
3581	/* Record and count probe trials on the ering.  The specific
3582	 * error mask used is irrelevant.  Because a successful device
3583	 * detection clears the ering, this count accumulates only if
3584	 * there are consecutive failed probes.
3585	 *
3586	 * If the count is equal to or higher than ATA_EH_PROBE_TRIALS
3587	 * in the last ATA_EH_PROBE_TRIAL_INTERVAL, link speed is
3588	 * forced to 1.5Gbps.
3589	 *
3590	 * This is to work around cases where failed link speed
3591	 * negotiation results in device misdetection leading to
3592	 * infinite DEVXCHG or PHRDY CHG events.
3593	 */
3594	ata_ering_record(&dev->ering, 0, AC_ERR_OTHER);
3595	ata_ering_map(&dev->ering, ata_count_probe_trials_cb, &trials);
3596
3597	if (trials > ATA_EH_PROBE_TRIALS)
3598		sata_down_spd_limit(link, 1);
3599
3600	return 1;
3601}
3602
3603static int ata_eh_handle_dev_fail(struct ata_device *dev, int err)
3604{
3605	struct ata_eh_context *ehc = &dev->link->eh_context;
3606
3607	/* -EAGAIN from EH routine indicates retry without prejudice.
3608	 * The requester is responsible for ensuring forward progress.
3609	 */
3610	if (err != -EAGAIN)
3611		ehc->tries[dev->devno]--;
3612
3613	switch (err) {
3614	case -ENODEV:
3615		/* device missing or wrong IDENTIFY data, schedule probing */
3616		ehc->i.probe_mask |= (1 << dev->devno);
3617		fallthrough;
3618	case -EINVAL:
3619		/* give it just one more chance */
3620		ehc->tries[dev->devno] = min(ehc->tries[dev->devno], 1);
3621		fallthrough;
3622	case -EIO:
3623		if (ehc->tries[dev->devno] == 1) {
3624			/* This is the last chance, better to slow
3625			 * down than lose it.
3626			 */
3627			sata_down_spd_limit(ata_dev_phys_link(dev), 0);
3628			if (dev->pio_mode > XFER_PIO_0)
3629				ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
3630		}
3631	}
3632
3633	if (ata_dev_enabled(dev) && !ehc->tries[dev->devno]) {
3634		/* disable device if it has used up all its chances */
3635		ata_dev_disable(dev);
3636
3637		/* detach if offline */
3638		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
3639			ata_eh_detach_dev(dev);
3640
3641		/* schedule probe if necessary */
3642		if (ata_eh_schedule_probe(dev)) {
3643			ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3644			memset(ehc->cmd_timeout_idx[dev->devno], 0,
3645			       sizeof(ehc->cmd_timeout_idx[dev->devno]));
3646		}
3647
3648		return 1;
3649	} else {
3650		ehc->i.action |= ATA_EH_RESET;
3651		return 0;
3652	}
3653}
3654
3655/**
3656 *	ata_eh_recover - recover host port after error
3657 *	@ap: host port to recover
3658 *	@prereset: prereset method (can be NULL)
3659 *	@softreset: softreset method (can be NULL)
3660 *	@hardreset: hardreset method (can be NULL)
3661 *	@postreset: postreset method (can be NULL)
3662 *	@r_failed_link: out parameter for failed link
3663 *
3664 *	This is the alpha and omega, eum and yang, heart and soul of
3665 *	libata exception handling.  On entry, actions required to
3666 *	recover each link and hotplug requests are recorded in the
3667 *	link's eh_context.  This function executes all the operations
3668 *	with appropriate retrials and fallbacks to resurrect failed
3669 *	devices, detach goners and greet newcomers.
3670 *
3671 *	LOCKING:
3672 *	Kernel thread context (may sleep).
3673 *
3674 *	RETURNS:
3675 *	0 on success, -errno on failure.
3676 */
3677int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
3678		   ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3679		   ata_postreset_fn_t postreset,
3680		   struct ata_link **r_failed_link)
3681{
3682	struct ata_link *link;
3683	struct ata_device *dev;
3684	int rc, nr_fails;
3685	unsigned long flags, deadline;
3686
3687	/* prep for recovery */
3688	ata_for_each_link(link, ap, EDGE) {
3689		struct ata_eh_context *ehc = &link->eh_context;
3690
3691		/* re-enable link? */
3692		if (ehc->i.action & ATA_EH_ENABLE_LINK) {
3693			ata_eh_about_to_do(link, NULL, ATA_EH_ENABLE_LINK);
3694			spin_lock_irqsave(ap->lock, flags);
3695			link->flags &= ~ATA_LFLAG_DISABLED;
3696			spin_unlock_irqrestore(ap->lock, flags);
3697			ata_eh_done(link, NULL, ATA_EH_ENABLE_LINK);
3698		}
3699
3700		ata_for_each_dev(dev, link, ALL) {
3701			if (link->flags & ATA_LFLAG_NO_RETRY)
3702				ehc->tries[dev->devno] = 1;
3703			else
3704				ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3705
3706			/* collect port action mask recorded in dev actions */
3707			ehc->i.action |= ehc->i.dev_action[dev->devno] &
3708					 ~ATA_EH_PERDEV_MASK;
3709			ehc->i.dev_action[dev->devno] &= ATA_EH_PERDEV_MASK;
3710
3711			/* process hotplug request */
3712			if (dev->flags & ATA_DFLAG_DETACH)
3713				ata_eh_detach_dev(dev);
3714
3715			/* schedule probe if necessary */
3716			if (!ata_dev_enabled(dev))
3717				ata_eh_schedule_probe(dev);
3718		}
3719	}
3720
3721 retry:
3722	rc = 0;
3723
3724	/* if UNLOADING, finish immediately */
3725	if (ap->pflags & ATA_PFLAG_UNLOADING)
3726		goto out;
3727
3728	/* prep for EH */
3729	ata_for_each_link(link, ap, EDGE) {
3730		struct ata_eh_context *ehc = &link->eh_context;
3731
3732		/* skip EH if possible. */
3733		if (ata_eh_skip_recovery(link))
3734			ehc->i.action = 0;
3735
3736		ata_for_each_dev(dev, link, ALL)
3737			ehc->classes[dev->devno] = ATA_DEV_UNKNOWN;
3738	}
3739
3740	/* reset */
3741	ata_for_each_link(link, ap, EDGE) {
3742		struct ata_eh_context *ehc = &link->eh_context;
3743
3744		if (!(ehc->i.action & ATA_EH_RESET))
3745			continue;
3746
3747		rc = ata_eh_reset(link, ata_link_nr_vacant(link),
3748				  prereset, softreset, hardreset, postreset);
3749		if (rc) {
3750			ata_link_err(link, "reset failed, giving up\n");
3751			goto out;
3752		}
3753	}
3754
3755	do {
3756		unsigned long now;
3757
3758		/*
3759		 * clears ATA_EH_PARK in eh_info and resets
3760		 * ap->park_req_pending
3761		 */
3762		ata_eh_pull_park_action(ap);
3763
3764		deadline = jiffies;
3765		ata_for_each_link(link, ap, EDGE) {
3766			ata_for_each_dev(dev, link, ALL) {
3767				struct ata_eh_context *ehc = &link->eh_context;
3768				unsigned long tmp;
3769
3770				if (dev->class != ATA_DEV_ATA &&
3771				    dev->class != ATA_DEV_ZAC)
3772					continue;
3773				if (!(ehc->i.dev_action[dev->devno] &
3774				      ATA_EH_PARK))
3775					continue;
3776				tmp = dev->unpark_deadline;
3777				if (time_before(deadline, tmp))
3778					deadline = tmp;
3779				else if (time_before_eq(tmp, jiffies))
3780					continue;
3781				if (ehc->unloaded_mask & (1 << dev->devno))
3782					continue;
3783
3784				ata_eh_park_issue_cmd(dev, 1);
3785			}
3786		}
3787
3788		now = jiffies;
3789		if (time_before_eq(deadline, now))
3790			break;
3791
3792		ata_eh_release(ap);
3793		deadline = wait_for_completion_timeout(&ap->park_req_pending,
3794						       deadline - now);
3795		ata_eh_acquire(ap);
3796	} while (deadline);
3797	ata_for_each_link(link, ap, EDGE) {
3798		ata_for_each_dev(dev, link, ALL) {
3799			if (!(link->eh_context.unloaded_mask &
3800			      (1 << dev->devno)))
3801				continue;
3802
3803			ata_eh_park_issue_cmd(dev, 0);
3804			ata_eh_done(link, dev, ATA_EH_PARK);
3805		}
3806	}
3807
3808	/* the rest */
3809	nr_fails = 0;
3810	ata_for_each_link(link, ap, PMP_FIRST) {
3811		struct ata_eh_context *ehc = &link->eh_context;
3812
3813		if (sata_pmp_attached(ap) && ata_is_host_link(link))
3814			goto config_lpm;
3815
3816		/* revalidate existing devices and attach new ones */
3817		rc = ata_eh_revalidate_and_attach(link, &dev);
3818		if (rc)
3819			goto rest_fail;
3820
3821		/* if PMP got attached, return, pmp EH will take care of it */
3822		if (link->device->class == ATA_DEV_PMP) {
3823			ehc->i.action = 0;
3824			return 0;
3825		}
3826
3827		/* configure transfer mode if necessary */
3828		if (ehc->i.flags & ATA_EHI_SETMODE) {
3829			rc = ata_set_mode(link, &dev);
3830			if (rc)
3831				goto rest_fail;
3832			ehc->i.flags &= ~ATA_EHI_SETMODE;
3833		}
3834
3835		/* If reset has been issued, clear UA to avoid
3836		 * disrupting the current users of the device.
3837		 */
3838		if (ehc->i.flags & ATA_EHI_DID_RESET) {
3839			ata_for_each_dev(dev, link, ALL) {
3840				if (dev->class != ATA_DEV_ATAPI)
3841					continue;
3842				rc = atapi_eh_clear_ua(dev);
3843				if (rc)
3844					goto rest_fail;
3845				if (zpodd_dev_enabled(dev))
3846					zpodd_post_poweron(dev);
3847			}
3848		}
3849
3850		/*
3851		 * Make sure to transition devices to the active power mode
3852		 * if needed (e.g. if we were scheduled on system resume).
3853		 */
3854		ata_for_each_dev(dev, link, ENABLED) {
3855			if (ehc->i.dev_action[dev->devno] & ATA_EH_SET_ACTIVE) {
3856				ata_dev_power_set_active(dev);
3857				ata_eh_done(link, dev, ATA_EH_SET_ACTIVE);
3858			}
3859		}
3860
3861		/* retry flush if necessary */
3862		ata_for_each_dev(dev, link, ALL) {
3863			if (dev->class != ATA_DEV_ATA &&
3864			    dev->class != ATA_DEV_ZAC)
3865				continue;
3866			rc = ata_eh_maybe_retry_flush(dev);
3867			if (rc)
3868				goto rest_fail;
3869		}
3870
3871	config_lpm:
3872		/* configure link power saving */
3873		if (link->lpm_policy != ap->target_lpm_policy) {
3874			rc = ata_eh_set_lpm(link, ap->target_lpm_policy, &dev);
3875			if (rc)
3876				goto rest_fail;
3877		}
3878
3879		/* this link is okay now */
3880		ehc->i.flags = 0;
3881		continue;
3882
3883	rest_fail:
3884		nr_fails++;
3885		if (dev)
3886			ata_eh_handle_dev_fail(dev, rc);
3887
3888		if (ata_port_is_frozen(ap)) {
3889			/* PMP reset requires working host port.
3890			 * Can't retry if it's frozen.
3891			 */
3892			if (sata_pmp_attached(ap))
3893				goto out;
3894			break;
3895		}
3896	}
3897
3898	if (nr_fails)
3899		goto retry;
3900
3901 out:
3902	if (rc && r_failed_link)
3903		*r_failed_link = link;
3904
3905	return rc;
3906}
3907
3908/**
3909 *	ata_eh_finish - finish up EH
3910 *	@ap: host port to finish EH for
3911 *
3912 *	Recovery is complete.  Clean up EH states and retry or finish
3913 *	failed qcs.
3914 *
3915 *	LOCKING:
3916 *	None.
3917 */
3918void ata_eh_finish(struct ata_port *ap)
3919{
3920	struct ata_queued_cmd *qc;
3921	int tag;
3922
3923	/* retry or finish qcs */
3924	ata_qc_for_each_raw(ap, qc, tag) {
3925		if (!(qc->flags & ATA_QCFLAG_EH))
3926			continue;
3927
3928		if (qc->err_mask) {
3929			/* FIXME: Once EH migration is complete,
3930			 * generate sense data in this function,
3931			 * considering both err_mask and tf.
3932			 */
3933			if (qc->flags & ATA_QCFLAG_RETRY) {
3934				/*
3935				 * Since qc->err_mask is set, ata_eh_qc_retry()
3936				 * will not increment scmd->allowed, so upper
3937				 * layer will only retry the command if it has
3938				 * not already been retried too many times.
3939				 */
3940				ata_eh_qc_retry(qc);
3941			} else {
3942				ata_eh_qc_complete(qc);
3943			}
3944		} else {
3945			if (qc->flags & ATA_QCFLAG_SENSE_VALID ||
3946			    qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD) {
3947				ata_eh_qc_complete(qc);
3948			} else {
3949				/* feed zero TF to sense generation */
3950				memset(&qc->result_tf, 0, sizeof(qc->result_tf));
3951				/*
3952				 * Since qc->err_mask is not set,
3953				 * ata_eh_qc_retry() will increment
3954				 * scmd->allowed, so upper layer is guaranteed
3955				 * to retry the command.
3956				 */
3957				ata_eh_qc_retry(qc);
3958			}
3959		}
3960	}
3961
3962	/* make sure nr_active_links is zero after EH */
3963	WARN_ON(ap->nr_active_links);
3964	ap->nr_active_links = 0;
3965}
3966
3967/**
3968 *	ata_do_eh - do standard error handling
3969 *	@ap: host port to handle error for
3970 *
3971 *	@prereset: prereset method (can be NULL)
3972 *	@softreset: softreset method (can be NULL)
3973 *	@hardreset: hardreset method (can be NULL)
3974 *	@postreset: postreset method (can be NULL)
3975 *
3976 *	Perform standard error handling sequence.
3977 *
3978 *	LOCKING:
3979 *	Kernel thread context (may sleep).
3980 */
3981void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
3982	       ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3983	       ata_postreset_fn_t postreset)
3984{
3985	struct ata_device *dev;
3986	int rc;
3987
3988	ata_eh_autopsy(ap);
3989	ata_eh_report(ap);
3990
3991	rc = ata_eh_recover(ap, prereset, softreset, hardreset, postreset,
3992			    NULL);
3993	if (rc) {
3994		ata_for_each_dev(dev, &ap->link, ALL)
3995			ata_dev_disable(dev);
3996	}
3997
3998	ata_eh_finish(ap);
3999}
4000
4001/**
4002 *	ata_std_error_handler - standard error handler
4003 *	@ap: host port to handle error for
4004 *
4005 *	Standard error handler
4006 *
4007 *	LOCKING:
4008 *	Kernel thread context (may sleep).
4009 */
4010void ata_std_error_handler(struct ata_port *ap)
4011{
4012	struct ata_port_operations *ops = ap->ops;
4013	ata_reset_fn_t hardreset = ops->hardreset;
4014
4015	/* ignore built-in hardreset if SCR access is not available */
4016	if (hardreset == sata_std_hardreset && !sata_scr_valid(&ap->link))
4017		hardreset = NULL;
4018
4019	ata_do_eh(ap, ops->prereset, ops->softreset, hardreset, ops->postreset);
4020}
4021EXPORT_SYMBOL_GPL(ata_std_error_handler);
4022
4023#ifdef CONFIG_PM
4024/**
4025 *	ata_eh_handle_port_suspend - perform port suspend operation
4026 *	@ap: port to suspend
4027 *
4028 *	Suspend @ap.
4029 *
4030 *	LOCKING:
4031 *	Kernel thread context (may sleep).
4032 */
4033static void ata_eh_handle_port_suspend(struct ata_port *ap)
4034{
4035	unsigned long flags;
4036	int rc = 0;
4037	struct ata_device *dev;
4038	struct ata_link *link;
4039
4040	/* are we suspending? */
4041	spin_lock_irqsave(ap->lock, flags);
4042	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
4043	    ap->pm_mesg.event & PM_EVENT_RESUME) {
4044		spin_unlock_irqrestore(ap->lock, flags);
4045		return;
4046	}
4047	spin_unlock_irqrestore(ap->lock, flags);
4048
4049	WARN_ON(ap->pflags & ATA_PFLAG_SUSPENDED);
4050
4051	/* Set all devices attached to the port in standby mode */
4052	ata_for_each_link(link, ap, HOST_FIRST) {
4053		ata_for_each_dev(dev, link, ENABLED)
4054			ata_dev_power_set_standby(dev);
4055	}
4056
4057	/*
4058	 * If we have a ZPODD attached, check its zero
4059	 * power ready status before the port is frozen.
4060	 * Only needed for runtime suspend.
4061	 */
4062	if (PMSG_IS_AUTO(ap->pm_mesg)) {
4063		ata_for_each_dev(dev, &ap->link, ENABLED) {
4064			if (zpodd_dev_enabled(dev))
4065				zpodd_on_suspend(dev);
4066		}
4067	}
4068
4069	/* suspend */
4070	ata_eh_freeze_port(ap);
4071
4072	if (ap->ops->port_suspend)
4073		rc = ap->ops->port_suspend(ap, ap->pm_mesg);
4074
4075	ata_acpi_set_state(ap, ap->pm_mesg);
4076
4077	/* update the flags */
4078	spin_lock_irqsave(ap->lock, flags);
4079
4080	ap->pflags &= ~ATA_PFLAG_PM_PENDING;
4081	if (rc == 0)
4082		ap->pflags |= ATA_PFLAG_SUSPENDED;
4083	else if (ata_port_is_frozen(ap))
4084		ata_port_schedule_eh(ap);
4085
4086	spin_unlock_irqrestore(ap->lock, flags);
4087
4088	return;
4089}
4090
4091/**
4092 *	ata_eh_handle_port_resume - perform port resume operation
4093 *	@ap: port to resume
4094 *
4095 *	Resume @ap.
4096 *
4097 *	LOCKING:
4098 *	Kernel thread context (may sleep).
4099 */
4100static void ata_eh_handle_port_resume(struct ata_port *ap)
4101{
4102	struct ata_link *link;
4103	struct ata_device *dev;
4104	unsigned long flags;
4105
4106	/* are we resuming? */
4107	spin_lock_irqsave(ap->lock, flags);
4108	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
4109	    !(ap->pm_mesg.event & PM_EVENT_RESUME)) {
4110		spin_unlock_irqrestore(ap->lock, flags);
4111		return;
4112	}
4113	spin_unlock_irqrestore(ap->lock, flags);
4114
4115	WARN_ON(!(ap->pflags & ATA_PFLAG_SUSPENDED));
4116
4117	/*
4118	 * Error timestamps are in jiffies which doesn't run while
4119	 * suspended and PHY events during resume isn't too uncommon.
4120	 * When the two are combined, it can lead to unnecessary speed
4121	 * downs if the machine is suspended and resumed repeatedly.
4122	 * Clear error history.
4123	 */
4124	ata_for_each_link(link, ap, HOST_FIRST)
4125		ata_for_each_dev(dev, link, ALL)
4126			ata_ering_clear(&dev->ering);
4127
4128	ata_acpi_set_state(ap, ap->pm_mesg);
4129
4130	if (ap->ops->port_resume)
4131		ap->ops->port_resume(ap);
4132
4133	/* tell ACPI that we're resuming */
4134	ata_acpi_on_resume(ap);
4135
4136	/* update the flags */
4137	spin_lock_irqsave(ap->lock, flags);
4138	ap->pflags &= ~(ATA_PFLAG_PM_PENDING | ATA_PFLAG_SUSPENDED);
4139	ap->pflags |= ATA_PFLAG_RESUMING;
4140	spin_unlock_irqrestore(ap->lock, flags);
4141}
4142#endif /* CONFIG_PM */