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v5.9
   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 long 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	ULONG_MAX,
  94};
  95
  96static const unsigned long ata_eh_flush_timeouts[] = {
  97	15000,	/* be generous with flush */
  98	15000,  /* ditto */
  99	30000,	/* and even more generous */
 100	ULONG_MAX,
 101};
 102
 103static const unsigned long ata_eh_other_timeouts[] = {
 104	 5000,	/* same rationale as identify timeout */
 105	10000,	/* ditto */
 106	/* but no merciful 30sec for other commands, it just isn't worth it */
 107	ULONG_MAX,
 108};
 109
 110struct ata_eh_cmd_timeout_ent {
 111	const u8		*commands;
 112	const unsigned long	*timeouts;
 113};
 114
 115/* The following table determines timeouts to use for EH internal
 116 * commands.  Each table entry is a command class and matches the
 117 * commands the entry applies to and the timeout table to use.
 118 *
 119 * On the retry after a command timed out, the next timeout value from
 120 * the table is used.  If the table doesn't contain further entries,
 121 * the last value is used.
 122 *
 123 * ehc->cmd_timeout_idx keeps track of which timeout to use per
 124 * command class, so if SET_FEATURES times out on the first try, the
 125 * next try will use the second timeout value only for that class.
 126 */
 127#define CMDS(cmds...)	(const u8 []){ cmds, 0 }
 128static const struct ata_eh_cmd_timeout_ent
 129ata_eh_cmd_timeout_table[ATA_EH_CMD_TIMEOUT_TABLE_SIZE] = {
 130	{ .commands = CMDS(ATA_CMD_ID_ATA, ATA_CMD_ID_ATAPI),
 131	  .timeouts = ata_eh_identify_timeouts, },
 132	{ .commands = CMDS(ATA_CMD_READ_NATIVE_MAX, ATA_CMD_READ_NATIVE_MAX_EXT),
 133	  .timeouts = ata_eh_other_timeouts, },
 134	{ .commands = CMDS(ATA_CMD_SET_MAX, ATA_CMD_SET_MAX_EXT),
 135	  .timeouts = ata_eh_other_timeouts, },
 136	{ .commands = CMDS(ATA_CMD_SET_FEATURES),
 137	  .timeouts = ata_eh_other_timeouts, },
 138	{ .commands = CMDS(ATA_CMD_INIT_DEV_PARAMS),
 139	  .timeouts = ata_eh_other_timeouts, },
 140	{ .commands = CMDS(ATA_CMD_FLUSH, ATA_CMD_FLUSH_EXT),
 141	  .timeouts = ata_eh_flush_timeouts },
 142};
 143#undef CMDS
 144
 145static void __ata_port_freeze(struct ata_port *ap);
 146#ifdef CONFIG_PM
 147static void ata_eh_handle_port_suspend(struct ata_port *ap);
 148static void ata_eh_handle_port_resume(struct ata_port *ap);
 149#else /* CONFIG_PM */
 150static void ata_eh_handle_port_suspend(struct ata_port *ap)
 151{ }
 152
 153static void ata_eh_handle_port_resume(struct ata_port *ap)
 154{ }
 155#endif /* CONFIG_PM */
 156
 157static __printf(2, 0) void __ata_ehi_pushv_desc(struct ata_eh_info *ehi,
 158				 const char *fmt, va_list args)
 159{
 160	ehi->desc_len += vscnprintf(ehi->desc + ehi->desc_len,
 161				     ATA_EH_DESC_LEN - ehi->desc_len,
 162				     fmt, args);
 163}
 164
 165/**
 166 *	__ata_ehi_push_desc - push error description without adding separator
 167 *	@ehi: target EHI
 168 *	@fmt: printf format string
 169 *
 170 *	Format string according to @fmt and append it to @ehi->desc.
 171 *
 172 *	LOCKING:
 173 *	spin_lock_irqsave(host lock)
 174 */
 175void __ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 176{
 177	va_list args;
 178
 179	va_start(args, fmt);
 180	__ata_ehi_pushv_desc(ehi, fmt, args);
 181	va_end(args);
 182}
 183EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
 184
 185/**
 186 *	ata_ehi_push_desc - push error description with separator
 187 *	@ehi: target EHI
 188 *	@fmt: printf format string
 189 *
 190 *	Format string according to @fmt and append it to @ehi->desc.
 191 *	If @ehi->desc is not empty, ", " is added in-between.
 192 *
 193 *	LOCKING:
 194 *	spin_lock_irqsave(host lock)
 195 */
 196void ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 197{
 198	va_list args;
 199
 200	if (ehi->desc_len)
 201		__ata_ehi_push_desc(ehi, ", ");
 202
 203	va_start(args, fmt);
 204	__ata_ehi_pushv_desc(ehi, fmt, args);
 205	va_end(args);
 206}
 207EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
 208
 209/**
 210 *	ata_ehi_clear_desc - clean error description
 211 *	@ehi: target EHI
 212 *
 213 *	Clear @ehi->desc.
 214 *
 215 *	LOCKING:
 216 *	spin_lock_irqsave(host lock)
 217 */
 218void ata_ehi_clear_desc(struct ata_eh_info *ehi)
 219{
 220	ehi->desc[0] = '\0';
 221	ehi->desc_len = 0;
 222}
 223EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
 224
 225/**
 226 *	ata_port_desc - append port description
 227 *	@ap: target ATA port
 228 *	@fmt: printf format string
 229 *
 230 *	Format string according to @fmt and append it to port
 231 *	description.  If port description is not empty, " " is added
 232 *	in-between.  This function is to be used while initializing
 233 *	ata_host.  The description is printed on host registration.
 234 *
 235 *	LOCKING:
 236 *	None.
 237 */
 238void ata_port_desc(struct ata_port *ap, const char *fmt, ...)
 239{
 240	va_list args;
 241
 242	WARN_ON(!(ap->pflags & ATA_PFLAG_INITIALIZING));
 243
 244	if (ap->link.eh_info.desc_len)
 245		__ata_ehi_push_desc(&ap->link.eh_info, " ");
 246
 247	va_start(args, fmt);
 248	__ata_ehi_pushv_desc(&ap->link.eh_info, fmt, args);
 249	va_end(args);
 250}
 251EXPORT_SYMBOL_GPL(ata_port_desc);
 252
 253#ifdef CONFIG_PCI
 254/**
 255 *	ata_port_pbar_desc - append PCI BAR description
 256 *	@ap: target ATA port
 257 *	@bar: target PCI BAR
 258 *	@offset: offset into PCI BAR
 259 *	@name: name of the area
 260 *
 261 *	If @offset is negative, this function formats a string which
 262 *	contains the name, address, size and type of the BAR and
 263 *	appends it to the port description.  If @offset is zero or
 264 *	positive, only name and offsetted address is appended.
 265 *
 266 *	LOCKING:
 267 *	None.
 268 */
 269void ata_port_pbar_desc(struct ata_port *ap, int bar, ssize_t offset,
 270			const char *name)
 271{
 272	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 273	char *type = "";
 274	unsigned long long start, len;
 275
 276	if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
 277		type = "m";
 278	else if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
 279		type = "i";
 280
 281	start = (unsigned long long)pci_resource_start(pdev, bar);
 282	len = (unsigned long long)pci_resource_len(pdev, bar);
 283
 284	if (offset < 0)
 285		ata_port_desc(ap, "%s %s%llu@0x%llx", name, type, len, start);
 286	else
 287		ata_port_desc(ap, "%s 0x%llx", name,
 288				start + (unsigned long long)offset);
 289}
 290EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
 291#endif /* CONFIG_PCI */
 292
 293static int ata_lookup_timeout_table(u8 cmd)
 294{
 295	int i;
 296
 297	for (i = 0; i < ATA_EH_CMD_TIMEOUT_TABLE_SIZE; i++) {
 298		const u8 *cur;
 299
 300		for (cur = ata_eh_cmd_timeout_table[i].commands; *cur; cur++)
 301			if (*cur == cmd)
 302				return i;
 303	}
 304
 305	return -1;
 306}
 307
 308/**
 309 *	ata_internal_cmd_timeout - determine timeout for an internal command
 310 *	@dev: target device
 311 *	@cmd: internal command to be issued
 312 *
 313 *	Determine timeout for internal command @cmd for @dev.
 314 *
 315 *	LOCKING:
 316 *	EH context.
 317 *
 318 *	RETURNS:
 319 *	Determined timeout.
 320 */
 321unsigned long ata_internal_cmd_timeout(struct ata_device *dev, u8 cmd)
 322{
 323	struct ata_eh_context *ehc = &dev->link->eh_context;
 324	int ent = ata_lookup_timeout_table(cmd);
 325	int idx;
 326
 327	if (ent < 0)
 328		return ATA_EH_CMD_DFL_TIMEOUT;
 329
 330	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 331	return ata_eh_cmd_timeout_table[ent].timeouts[idx];
 332}
 333
 334/**
 335 *	ata_internal_cmd_timed_out - notification for internal command timeout
 336 *	@dev: target device
 337 *	@cmd: internal command which timed out
 338 *
 339 *	Notify EH that internal command @cmd for @dev timed out.  This
 340 *	function should be called only for commands whose timeouts are
 341 *	determined using ata_internal_cmd_timeout().
 342 *
 343 *	LOCKING:
 344 *	EH context.
 345 */
 346void ata_internal_cmd_timed_out(struct ata_device *dev, u8 cmd)
 347{
 348	struct ata_eh_context *ehc = &dev->link->eh_context;
 349	int ent = ata_lookup_timeout_table(cmd);
 350	int idx;
 351
 352	if (ent < 0)
 353		return;
 354
 355	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 356	if (ata_eh_cmd_timeout_table[ent].timeouts[idx + 1] != ULONG_MAX)
 357		ehc->cmd_timeout_idx[dev->devno][ent]++;
 358}
 359
 360static void ata_ering_record(struct ata_ering *ering, unsigned int eflags,
 361			     unsigned int err_mask)
 362{
 363	struct ata_ering_entry *ent;
 364
 365	WARN_ON(!err_mask);
 366
 367	ering->cursor++;
 368	ering->cursor %= ATA_ERING_SIZE;
 369
 370	ent = &ering->ring[ering->cursor];
 371	ent->eflags = eflags;
 372	ent->err_mask = err_mask;
 373	ent->timestamp = get_jiffies_64();
 374}
 375
 376static struct ata_ering_entry *ata_ering_top(struct ata_ering *ering)
 377{
 378	struct ata_ering_entry *ent = &ering->ring[ering->cursor];
 379
 380	if (ent->err_mask)
 381		return ent;
 382	return NULL;
 383}
 384
 385int ata_ering_map(struct ata_ering *ering,
 386		  int (*map_fn)(struct ata_ering_entry *, void *),
 387		  void *arg)
 388{
 389	int idx, rc = 0;
 390	struct ata_ering_entry *ent;
 391
 392	idx = ering->cursor;
 393	do {
 394		ent = &ering->ring[idx];
 395		if (!ent->err_mask)
 396			break;
 397		rc = map_fn(ent, arg);
 398		if (rc)
 399			break;
 400		idx = (idx - 1 + ATA_ERING_SIZE) % ATA_ERING_SIZE;
 401	} while (idx != ering->cursor);
 402
 403	return rc;
 404}
 405
 406static int ata_ering_clear_cb(struct ata_ering_entry *ent, void *void_arg)
 407{
 408	ent->eflags |= ATA_EFLAG_OLD_ER;
 409	return 0;
 410}
 411
 412static void ata_ering_clear(struct ata_ering *ering)
 413{
 414	ata_ering_map(ering, ata_ering_clear_cb, NULL);
 415}
 416
 417static unsigned int ata_eh_dev_action(struct ata_device *dev)
 418{
 419	struct ata_eh_context *ehc = &dev->link->eh_context;
 420
 421	return ehc->i.action | ehc->i.dev_action[dev->devno];
 422}
 423
 424static void ata_eh_clear_action(struct ata_link *link, struct ata_device *dev,
 425				struct ata_eh_info *ehi, unsigned int action)
 426{
 427	struct ata_device *tdev;
 428
 429	if (!dev) {
 430		ehi->action &= ~action;
 431		ata_for_each_dev(tdev, link, ALL)
 432			ehi->dev_action[tdev->devno] &= ~action;
 433	} else {
 434		/* doesn't make sense for port-wide EH actions */
 435		WARN_ON(!(action & ATA_EH_PERDEV_MASK));
 436
 437		/* break ehi->action into ehi->dev_action */
 438		if (ehi->action & action) {
 439			ata_for_each_dev(tdev, link, ALL)
 440				ehi->dev_action[tdev->devno] |=
 441					ehi->action & action;
 442			ehi->action &= ~action;
 443		}
 444
 445		/* turn off the specified per-dev action */
 446		ehi->dev_action[dev->devno] &= ~action;
 447	}
 448}
 449
 450/**
 451 *	ata_eh_acquire - acquire EH ownership
 452 *	@ap: ATA port to acquire EH ownership for
 453 *
 454 *	Acquire EH ownership for @ap.  This is the basic exclusion
 455 *	mechanism for ports sharing a host.  Only one port hanging off
 456 *	the same host can claim the ownership of EH.
 457 *
 458 *	LOCKING:
 459 *	EH context.
 460 */
 461void ata_eh_acquire(struct ata_port *ap)
 462{
 463	mutex_lock(&ap->host->eh_mutex);
 464	WARN_ON_ONCE(ap->host->eh_owner);
 465	ap->host->eh_owner = current;
 466}
 467
 468/**
 469 *	ata_eh_release - release EH ownership
 470 *	@ap: ATA port to release EH ownership for
 471 *
 472 *	Release EH ownership for @ap if the caller.  The caller must
 473 *	have acquired EH ownership using ata_eh_acquire() previously.
 474 *
 475 *	LOCKING:
 476 *	EH context.
 477 */
 478void ata_eh_release(struct ata_port *ap)
 479{
 480	WARN_ON_ONCE(ap->host->eh_owner != current);
 481	ap->host->eh_owner = NULL;
 482	mutex_unlock(&ap->host->eh_mutex);
 483}
 484
 485static void ata_eh_unload(struct ata_port *ap)
 486{
 487	struct ata_link *link;
 488	struct ata_device *dev;
 489	unsigned long flags;
 490
 491	/* Restore SControl IPM and SPD for the next driver and
 492	 * disable attached devices.
 493	 */
 494	ata_for_each_link(link, ap, PMP_FIRST) {
 495		sata_scr_write(link, SCR_CONTROL, link->saved_scontrol & 0xff0);
 496		ata_for_each_dev(dev, link, ALL)
 497			ata_dev_disable(dev);
 498	}
 499
 500	/* freeze and set UNLOADED */
 501	spin_lock_irqsave(ap->lock, flags);
 502
 503	ata_port_freeze(ap);			/* won't be thawed */
 504	ap->pflags &= ~ATA_PFLAG_EH_PENDING;	/* clear pending from freeze */
 505	ap->pflags |= ATA_PFLAG_UNLOADED;
 506
 507	spin_unlock_irqrestore(ap->lock, flags);
 508}
 509
 510/**
 511 *	ata_scsi_error - SCSI layer error handler callback
 512 *	@host: SCSI host on which error occurred
 513 *
 514 *	Handles SCSI-layer-thrown error events.
 515 *
 516 *	LOCKING:
 517 *	Inherited from SCSI layer (none, can sleep)
 518 *
 519 *	RETURNS:
 520 *	Zero.
 521 */
 522void ata_scsi_error(struct Scsi_Host *host)
 523{
 524	struct ata_port *ap = ata_shost_to_port(host);
 525	unsigned long flags;
 526	LIST_HEAD(eh_work_q);
 527
 528	DPRINTK("ENTER\n");
 529
 530	spin_lock_irqsave(host->host_lock, flags);
 531	list_splice_init(&host->eh_cmd_q, &eh_work_q);
 532	spin_unlock_irqrestore(host->host_lock, flags);
 533
 534	ata_scsi_cmd_error_handler(host, ap, &eh_work_q);
 535
 536	/* If we timed raced normal completion and there is nothing to
 537	   recover nr_timedout == 0 why exactly are we doing error recovery ? */
 538	ata_scsi_port_error_handler(host, ap);
 539
 540	/* finish or retry handled scmd's and clean up */
 541	WARN_ON(!list_empty(&eh_work_q));
 542
 543	DPRINTK("EXIT\n");
 544}
 545
 546/**
 547 * ata_scsi_cmd_error_handler - error callback for a list of commands
 548 * @host:	scsi host containing the port
 549 * @ap:		ATA port within the host
 550 * @eh_work_q:	list of commands to process
 551 *
 552 * process the given list of commands and return those finished to the
 553 * ap->eh_done_q.  This function is the first part of the libata error
 554 * handler which processes a given list of failed commands.
 555 */
 556void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
 557				struct list_head *eh_work_q)
 558{
 559	int i;
 560	unsigned long flags;
 561
 562	/* make sure sff pio task is not running */
 563	ata_sff_flush_pio_task(ap);
 564
 565	/* synchronize with host lock and sort out timeouts */
 566
 567	/* For new EH, all qcs are finished in one of three ways -
 568	 * normal completion, error completion, and SCSI timeout.
 569	 * Both completions can race against SCSI timeout.  When normal
 570	 * completion wins, the qc never reaches EH.  When error
 571	 * completion wins, the qc has ATA_QCFLAG_FAILED set.
 572	 *
 573	 * When SCSI timeout wins, things are a bit more complex.
 574	 * Normal or error completion can occur after the timeout but
 575	 * before this point.  In such cases, both types of
 576	 * completions are honored.  A scmd is determined to have
 577	 * timed out iff its associated qc is active and not failed.
 578	 */
 579	spin_lock_irqsave(ap->lock, flags);
 580	if (ap->ops->error_handler) {
 581		struct scsi_cmnd *scmd, *tmp;
 582		int nr_timedout = 0;
 583
 584		/* This must occur under the ap->lock as we don't want
 585		   a polled recovery to race the real interrupt handler
 586
 587		   The lost_interrupt handler checks for any completed but
 588		   non-notified command and completes much like an IRQ handler.
 589
 590		   We then fall into the error recovery code which will treat
 591		   this as if normal completion won the race */
 592
 593		if (ap->ops->lost_interrupt)
 594			ap->ops->lost_interrupt(ap);
 595
 596		list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
 597			struct ata_queued_cmd *qc;
 598
 599			ata_qc_for_each_raw(ap, qc, i) {
 600				if (qc->flags & ATA_QCFLAG_ACTIVE &&
 601				    qc->scsicmd == scmd)
 602					break;
 603			}
 604
 605			if (i < ATA_MAX_QUEUE) {
 606				/* the scmd has an associated qc */
 607				if (!(qc->flags & ATA_QCFLAG_FAILED)) {
 608					/* which hasn't failed yet, timeout */
 609					qc->err_mask |= AC_ERR_TIMEOUT;
 610					qc->flags |= ATA_QCFLAG_FAILED;
 611					nr_timedout++;
 612				}
 613			} else {
 614				/* Normal completion occurred after
 615				 * SCSI timeout but before this point.
 616				 * Successfully complete it.
 617				 */
 618				scmd->retries = scmd->allowed;
 619				scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
 620			}
 621		}
 622
 623		/* If we have timed out qcs.  They belong to EH from
 624		 * this point but the state of the controller is
 625		 * unknown.  Freeze the port to make sure the IRQ
 626		 * handler doesn't diddle with those qcs.  This must
 627		 * be done atomically w.r.t. setting QCFLAG_FAILED.
 628		 */
 629		if (nr_timedout)
 630			__ata_port_freeze(ap);
 631
 632
 633		/* initialize eh_tries */
 634		ap->eh_tries = ATA_EH_MAX_TRIES;
 635	}
 636	spin_unlock_irqrestore(ap->lock, flags);
 637
 638}
 639EXPORT_SYMBOL(ata_scsi_cmd_error_handler);
 640
 641/**
 642 * ata_scsi_port_error_handler - recover the port after the commands
 643 * @host:	SCSI host containing the port
 644 * @ap:		the ATA port
 645 *
 646 * Handle the recovery of the port @ap after all the commands
 647 * have been recovered.
 648 */
 649void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap)
 650{
 651	unsigned long flags;
 652
 653	/* invoke error handler */
 654	if (ap->ops->error_handler) {
 655		struct ata_link *link;
 656
 657		/* acquire EH ownership */
 658		ata_eh_acquire(ap);
 659 repeat:
 660		/* kill fast drain timer */
 661		del_timer_sync(&ap->fastdrain_timer);
 662
 663		/* process port resume request */
 664		ata_eh_handle_port_resume(ap);
 665
 666		/* fetch & clear EH info */
 667		spin_lock_irqsave(ap->lock, flags);
 668
 669		ata_for_each_link(link, ap, HOST_FIRST) {
 670			struct ata_eh_context *ehc = &link->eh_context;
 671			struct ata_device *dev;
 672
 673			memset(&link->eh_context, 0, sizeof(link->eh_context));
 674			link->eh_context.i = link->eh_info;
 675			memset(&link->eh_info, 0, sizeof(link->eh_info));
 676
 677			ata_for_each_dev(dev, link, ENABLED) {
 678				int devno = dev->devno;
 679
 680				ehc->saved_xfer_mode[devno] = dev->xfer_mode;
 681				if (ata_ncq_enabled(dev))
 682					ehc->saved_ncq_enabled |= 1 << devno;
 683			}
 684		}
 685
 686		ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
 687		ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 688		ap->excl_link = NULL;	/* don't maintain exclusion over EH */
 689
 690		spin_unlock_irqrestore(ap->lock, flags);
 691
 692		/* invoke EH, skip if unloading or suspended */
 693		if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))
 694			ap->ops->error_handler(ap);
 695		else {
 696			/* if unloading, commence suicide */
 697			if ((ap->pflags & ATA_PFLAG_UNLOADING) &&
 698			    !(ap->pflags & ATA_PFLAG_UNLOADED))
 699				ata_eh_unload(ap);
 700			ata_eh_finish(ap);
 701		}
 702
 703		/* process port suspend request */
 704		ata_eh_handle_port_suspend(ap);
 705
 706		/* Exception might have happened after ->error_handler
 707		 * recovered the port but before this point.  Repeat
 708		 * EH in such case.
 709		 */
 710		spin_lock_irqsave(ap->lock, flags);
 711
 712		if (ap->pflags & ATA_PFLAG_EH_PENDING) {
 713			if (--ap->eh_tries) {
 714				spin_unlock_irqrestore(ap->lock, flags);
 715				goto repeat;
 716			}
 717			ata_port_err(ap,
 718				     "EH pending after %d tries, giving up\n",
 719				     ATA_EH_MAX_TRIES);
 720			ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 721		}
 722
 723		/* this run is complete, make sure EH info is clear */
 724		ata_for_each_link(link, ap, HOST_FIRST)
 725			memset(&link->eh_info, 0, sizeof(link->eh_info));
 726
 727		/* end eh (clear host_eh_scheduled) while holding
 728		 * ap->lock such that if exception occurs after this
 729		 * point but before EH completion, SCSI midlayer will
 730		 * re-initiate EH.
 731		 */
 732		ap->ops->end_eh(ap);
 733
 734		spin_unlock_irqrestore(ap->lock, flags);
 735		ata_eh_release(ap);
 736	} else {
 737		WARN_ON(ata_qc_from_tag(ap, ap->link.active_tag) == NULL);
 738		ap->ops->eng_timeout(ap);
 739	}
 740
 741	scsi_eh_flush_done_q(&ap->eh_done_q);
 742
 743	/* clean up */
 744	spin_lock_irqsave(ap->lock, flags);
 745
 746	if (ap->pflags & ATA_PFLAG_LOADING)
 747		ap->pflags &= ~ATA_PFLAG_LOADING;
 748	else if ((ap->pflags & ATA_PFLAG_SCSI_HOTPLUG) &&
 749		!(ap->flags & ATA_FLAG_SAS_HOST))
 750		schedule_delayed_work(&ap->hotplug_task, 0);
 751
 752	if (ap->pflags & ATA_PFLAG_RECOVERED)
 753		ata_port_info(ap, "EH complete\n");
 754
 755	ap->pflags &= ~(ATA_PFLAG_SCSI_HOTPLUG | ATA_PFLAG_RECOVERED);
 756
 757	/* tell wait_eh that we're done */
 758	ap->pflags &= ~ATA_PFLAG_EH_IN_PROGRESS;
 759	wake_up_all(&ap->eh_wait_q);
 760
 761	spin_unlock_irqrestore(ap->lock, flags);
 762}
 763EXPORT_SYMBOL_GPL(ata_scsi_port_error_handler);
 764
 765/**
 766 *	ata_port_wait_eh - Wait for the currently pending EH to complete
 767 *	@ap: Port to wait EH for
 768 *
 769 *	Wait until the currently pending EH is complete.
 770 *
 771 *	LOCKING:
 772 *	Kernel thread context (may sleep).
 773 */
 774void ata_port_wait_eh(struct ata_port *ap)
 775{
 776	unsigned long flags;
 777	DEFINE_WAIT(wait);
 778
 779 retry:
 780	spin_lock_irqsave(ap->lock, flags);
 781
 782	while (ap->pflags & (ATA_PFLAG_EH_PENDING | ATA_PFLAG_EH_IN_PROGRESS)) {
 783		prepare_to_wait(&ap->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 784		spin_unlock_irqrestore(ap->lock, flags);
 785		schedule();
 786		spin_lock_irqsave(ap->lock, flags);
 787	}
 788	finish_wait(&ap->eh_wait_q, &wait);
 789
 790	spin_unlock_irqrestore(ap->lock, flags);
 791
 792	/* make sure SCSI EH is complete */
 793	if (scsi_host_in_recovery(ap->scsi_host)) {
 794		ata_msleep(ap, 10);
 795		goto retry;
 796	}
 797}
 798EXPORT_SYMBOL_GPL(ata_port_wait_eh);
 799
 800static int ata_eh_nr_in_flight(struct ata_port *ap)
 801{
 802	struct ata_queued_cmd *qc;
 803	unsigned int tag;
 804	int nr = 0;
 805
 806	/* count only non-internal commands */
 807	ata_qc_for_each(ap, qc, tag) {
 808		if (qc)
 809			nr++;
 810	}
 811
 812	return nr;
 813}
 814
 815void ata_eh_fastdrain_timerfn(struct timer_list *t)
 816{
 817	struct ata_port *ap = from_timer(ap, t, fastdrain_timer);
 818	unsigned long flags;
 819	int cnt;
 820
 821	spin_lock_irqsave(ap->lock, flags);
 822
 823	cnt = ata_eh_nr_in_flight(ap);
 824
 825	/* are we done? */
 826	if (!cnt)
 827		goto out_unlock;
 828
 829	if (cnt == ap->fastdrain_cnt) {
 830		struct ata_queued_cmd *qc;
 831		unsigned int tag;
 832
 833		/* No progress during the last interval, tag all
 834		 * in-flight qcs as timed out and freeze the port.
 835		 */
 836		ata_qc_for_each(ap, qc, tag) {
 837			if (qc)
 838				qc->err_mask |= AC_ERR_TIMEOUT;
 839		}
 840
 841		ata_port_freeze(ap);
 842	} else {
 843		/* some qcs have finished, give it another chance */
 844		ap->fastdrain_cnt = cnt;
 845		ap->fastdrain_timer.expires =
 846			ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 847		add_timer(&ap->fastdrain_timer);
 848	}
 849
 850 out_unlock:
 851	spin_unlock_irqrestore(ap->lock, flags);
 852}
 853
 854/**
 855 *	ata_eh_set_pending - set ATA_PFLAG_EH_PENDING and activate fast drain
 856 *	@ap: target ATA port
 857 *	@fastdrain: activate fast drain
 858 *
 859 *	Set ATA_PFLAG_EH_PENDING and activate fast drain if @fastdrain
 860 *	is non-zero and EH wasn't pending before.  Fast drain ensures
 861 *	that EH kicks in in timely manner.
 862 *
 863 *	LOCKING:
 864 *	spin_lock_irqsave(host lock)
 865 */
 866static void ata_eh_set_pending(struct ata_port *ap, int fastdrain)
 867{
 868	int cnt;
 869
 870	/* already scheduled? */
 871	if (ap->pflags & ATA_PFLAG_EH_PENDING)
 872		return;
 873
 874	ap->pflags |= ATA_PFLAG_EH_PENDING;
 875
 876	if (!fastdrain)
 877		return;
 878
 879	/* do we have in-flight qcs? */
 880	cnt = ata_eh_nr_in_flight(ap);
 881	if (!cnt)
 882		return;
 883
 884	/* activate fast drain */
 885	ap->fastdrain_cnt = cnt;
 886	ap->fastdrain_timer.expires =
 887		ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 888	add_timer(&ap->fastdrain_timer);
 889}
 890
 891/**
 892 *	ata_qc_schedule_eh - schedule qc for error handling
 893 *	@qc: command to schedule error handling for
 894 *
 895 *	Schedule error handling for @qc.  EH will kick in as soon as
 896 *	other commands are drained.
 897 *
 898 *	LOCKING:
 899 *	spin_lock_irqsave(host lock)
 900 */
 901void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
 902{
 903	struct ata_port *ap = qc->ap;
 904
 905	WARN_ON(!ap->ops->error_handler);
 906
 907	qc->flags |= ATA_QCFLAG_FAILED;
 908	ata_eh_set_pending(ap, 1);
 909
 910	/* The following will fail if timeout has already expired.
 911	 * ata_scsi_error() takes care of such scmds on EH entry.
 912	 * Note that ATA_QCFLAG_FAILED is unconditionally set after
 913	 * this function completes.
 914	 */
 915	blk_abort_request(qc->scsicmd->request);
 916}
 917
 918/**
 919 * ata_std_sched_eh - non-libsas ata_ports issue eh with this common routine
 920 * @ap: ATA port to schedule EH for
 921 *
 922 *	LOCKING: inherited from ata_port_schedule_eh
 923 *	spin_lock_irqsave(host lock)
 924 */
 925void ata_std_sched_eh(struct ata_port *ap)
 926{
 927	WARN_ON(!ap->ops->error_handler);
 928
 929	if (ap->pflags & ATA_PFLAG_INITIALIZING)
 930		return;
 931
 932	ata_eh_set_pending(ap, 1);
 933	scsi_schedule_eh(ap->scsi_host);
 934
 935	DPRINTK("port EH scheduled\n");
 936}
 937EXPORT_SYMBOL_GPL(ata_std_sched_eh);
 938
 939/**
 940 * ata_std_end_eh - non-libsas ata_ports complete eh with this common routine
 941 * @ap: ATA port to end EH for
 942 *
 943 * In the libata object model there is a 1:1 mapping of ata_port to
 944 * shost, so host fields can be directly manipulated under ap->lock, in
 945 * the libsas case we need to hold a lock at the ha->level to coordinate
 946 * these events.
 947 *
 948 *	LOCKING:
 949 *	spin_lock_irqsave(host lock)
 950 */
 951void ata_std_end_eh(struct ata_port *ap)
 952{
 953	struct Scsi_Host *host = ap->scsi_host;
 954
 955	host->host_eh_scheduled = 0;
 956}
 957EXPORT_SYMBOL(ata_std_end_eh);
 958
 959
 960/**
 961 *	ata_port_schedule_eh - schedule error handling without a qc
 962 *	@ap: ATA port to schedule EH for
 963 *
 964 *	Schedule error handling for @ap.  EH will kick in as soon as
 965 *	all commands are drained.
 966 *
 967 *	LOCKING:
 968 *	spin_lock_irqsave(host lock)
 969 */
 970void ata_port_schedule_eh(struct ata_port *ap)
 971{
 972	/* see: ata_std_sched_eh, unless you know better */
 973	ap->ops->sched_eh(ap);
 974}
 975EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
 976
 977static int ata_do_link_abort(struct ata_port *ap, struct ata_link *link)
 978{
 979	struct ata_queued_cmd *qc;
 980	int tag, nr_aborted = 0;
 981
 982	WARN_ON(!ap->ops->error_handler);
 983
 984	/* we're gonna abort all commands, no need for fast drain */
 985	ata_eh_set_pending(ap, 0);
 986
 987	/* include internal tag in iteration */
 988	ata_qc_for_each_with_internal(ap, qc, tag) {
 989		if (qc && (!link || qc->dev->link == link)) {
 990			qc->flags |= ATA_QCFLAG_FAILED;
 991			ata_qc_complete(qc);
 992			nr_aborted++;
 993		}
 994	}
 995
 996	if (!nr_aborted)
 997		ata_port_schedule_eh(ap);
 998
 999	return nr_aborted;
1000}
1001
1002/**
1003 *	ata_link_abort - abort all qc's on the link
1004 *	@link: ATA link to abort qc's for
1005 *
1006 *	Abort all active qc's active on @link and schedule EH.
1007 *
1008 *	LOCKING:
1009 *	spin_lock_irqsave(host lock)
1010 *
1011 *	RETURNS:
1012 *	Number of aborted qc's.
1013 */
1014int ata_link_abort(struct ata_link *link)
1015{
1016	return ata_do_link_abort(link->ap, link);
1017}
1018EXPORT_SYMBOL_GPL(ata_link_abort);
1019
1020/**
1021 *	ata_port_abort - abort all qc's on the port
1022 *	@ap: ATA port to abort qc's for
1023 *
1024 *	Abort all active qc's of @ap and schedule EH.
1025 *
1026 *	LOCKING:
1027 *	spin_lock_irqsave(host_set lock)
1028 *
1029 *	RETURNS:
1030 *	Number of aborted qc's.
1031 */
1032int ata_port_abort(struct ata_port *ap)
1033{
1034	return ata_do_link_abort(ap, NULL);
1035}
1036EXPORT_SYMBOL_GPL(ata_port_abort);
1037
1038/**
1039 *	__ata_port_freeze - freeze port
1040 *	@ap: ATA port to freeze
1041 *
1042 *	This function is called when HSM violation or some other
1043 *	condition disrupts normal operation of the port.  Frozen port
1044 *	is not allowed to perform any operation until the port is
1045 *	thawed, which usually follows a successful reset.
1046 *
1047 *	ap->ops->freeze() callback can be used for freezing the port
1048 *	hardware-wise (e.g. mask interrupt and stop DMA engine).  If a
1049 *	port cannot be frozen hardware-wise, the interrupt handler
1050 *	must ack and clear interrupts unconditionally while the port
1051 *	is frozen.
1052 *
1053 *	LOCKING:
1054 *	spin_lock_irqsave(host lock)
1055 */
1056static void __ata_port_freeze(struct ata_port *ap)
1057{
1058	WARN_ON(!ap->ops->error_handler);
1059
1060	if (ap->ops->freeze)
1061		ap->ops->freeze(ap);
1062
1063	ap->pflags |= ATA_PFLAG_FROZEN;
1064
1065	DPRINTK("ata%u port frozen\n", ap->print_id);
1066}
1067
1068/**
1069 *	ata_port_freeze - abort & freeze port
1070 *	@ap: ATA port to freeze
1071 *
1072 *	Abort and freeze @ap.  The freeze operation must be called
1073 *	first, because some hardware requires special operations
1074 *	before the taskfile registers are accessible.
1075 *
1076 *	LOCKING:
1077 *	spin_lock_irqsave(host lock)
1078 *
1079 *	RETURNS:
1080 *	Number of aborted commands.
1081 */
1082int ata_port_freeze(struct ata_port *ap)
1083{
1084	int nr_aborted;
1085
1086	WARN_ON(!ap->ops->error_handler);
1087
1088	__ata_port_freeze(ap);
1089	nr_aborted = ata_port_abort(ap);
1090
1091	return nr_aborted;
1092}
1093EXPORT_SYMBOL_GPL(ata_port_freeze);
1094
1095/**
1096 *	ata_eh_freeze_port - EH helper to freeze port
1097 *	@ap: ATA port to freeze
1098 *
1099 *	Freeze @ap.
1100 *
1101 *	LOCKING:
1102 *	None.
1103 */
1104void ata_eh_freeze_port(struct ata_port *ap)
1105{
1106	unsigned long flags;
1107
1108	if (!ap->ops->error_handler)
1109		return;
1110
1111	spin_lock_irqsave(ap->lock, flags);
1112	__ata_port_freeze(ap);
1113	spin_unlock_irqrestore(ap->lock, flags);
1114}
1115EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
1116
1117/**
1118 *	ata_port_thaw_port - EH helper to thaw port
1119 *	@ap: ATA port to thaw
1120 *
1121 *	Thaw frozen port @ap.
1122 *
1123 *	LOCKING:
1124 *	None.
1125 */
1126void ata_eh_thaw_port(struct ata_port *ap)
1127{
1128	unsigned long flags;
1129
1130	if (!ap->ops->error_handler)
1131		return;
1132
1133	spin_lock_irqsave(ap->lock, flags);
1134
1135	ap->pflags &= ~ATA_PFLAG_FROZEN;
1136
1137	if (ap->ops->thaw)
1138		ap->ops->thaw(ap);
1139
1140	spin_unlock_irqrestore(ap->lock, flags);
1141
1142	DPRINTK("ata%u port thawed\n", ap->print_id);
1143}
1144
1145static void ata_eh_scsidone(struct scsi_cmnd *scmd)
1146{
1147	/* nada */
1148}
1149
1150static void __ata_eh_qc_complete(struct ata_queued_cmd *qc)
1151{
1152	struct ata_port *ap = qc->ap;
1153	struct scsi_cmnd *scmd = qc->scsicmd;
1154	unsigned long flags;
1155
1156	spin_lock_irqsave(ap->lock, flags);
1157	qc->scsidone = ata_eh_scsidone;
1158	__ata_qc_complete(qc);
1159	WARN_ON(ata_tag_valid(qc->tag));
1160	spin_unlock_irqrestore(ap->lock, flags);
1161
1162	scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
1163}
1164
1165/**
1166 *	ata_eh_qc_complete - Complete an active ATA command from EH
1167 *	@qc: Command to complete
1168 *
1169 *	Indicate to the mid and upper layers that an ATA command has
1170 *	completed.  To be used from EH.
1171 */
1172void ata_eh_qc_complete(struct ata_queued_cmd *qc)
1173{
1174	struct scsi_cmnd *scmd = qc->scsicmd;
1175	scmd->retries = scmd->allowed;
1176	__ata_eh_qc_complete(qc);
1177}
1178
1179/**
1180 *	ata_eh_qc_retry - Tell midlayer to retry an ATA command after EH
1181 *	@qc: Command to retry
1182 *
1183 *	Indicate to the mid and upper layers that an ATA command
1184 *	should be retried.  To be used from EH.
1185 *
1186 *	SCSI midlayer limits the number of retries to scmd->allowed.
1187 *	scmd->allowed is incremented for commands which get retried
1188 *	due to unrelated failures (qc->err_mask is zero).
1189 */
1190void ata_eh_qc_retry(struct ata_queued_cmd *qc)
1191{
1192	struct scsi_cmnd *scmd = qc->scsicmd;
1193	if (!qc->err_mask)
1194		scmd->allowed++;
1195	__ata_eh_qc_complete(qc);
1196}
1197
1198/**
1199 *	ata_dev_disable - disable ATA device
1200 *	@dev: ATA device to disable
1201 *
1202 *	Disable @dev.
1203 *
1204 *	Locking:
1205 *	EH context.
1206 */
1207void ata_dev_disable(struct ata_device *dev)
1208{
1209	if (!ata_dev_enabled(dev))
1210		return;
1211
1212	if (ata_msg_drv(dev->link->ap))
1213		ata_dev_warn(dev, "disabled\n");
1214	ata_acpi_on_disable(dev);
1215	ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 | ATA_DNXFER_QUIET);
1216	dev->class++;
1217
1218	/* From now till the next successful probe, ering is used to
1219	 * track probe failures.  Clear accumulated device error info.
1220	 */
1221	ata_ering_clear(&dev->ering);
1222}
1223EXPORT_SYMBOL_GPL(ata_dev_disable);
1224
1225/**
1226 *	ata_eh_detach_dev - detach ATA device
1227 *	@dev: ATA device to detach
1228 *
1229 *	Detach @dev.
1230 *
1231 *	LOCKING:
1232 *	None.
1233 */
1234void ata_eh_detach_dev(struct ata_device *dev)
1235{
1236	struct ata_link *link = dev->link;
1237	struct ata_port *ap = link->ap;
1238	struct ata_eh_context *ehc = &link->eh_context;
1239	unsigned long flags;
1240
1241	ata_dev_disable(dev);
1242
1243	spin_lock_irqsave(ap->lock, flags);
1244
1245	dev->flags &= ~ATA_DFLAG_DETACH;
1246
1247	if (ata_scsi_offline_dev(dev)) {
1248		dev->flags |= ATA_DFLAG_DETACHED;
1249		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
1250	}
1251
1252	/* clear per-dev EH info */
1253	ata_eh_clear_action(link, dev, &link->eh_info, ATA_EH_PERDEV_MASK);
1254	ata_eh_clear_action(link, dev, &link->eh_context.i, ATA_EH_PERDEV_MASK);
1255	ehc->saved_xfer_mode[dev->devno] = 0;
1256	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
1257
1258	spin_unlock_irqrestore(ap->lock, flags);
1259}
1260
1261/**
1262 *	ata_eh_about_to_do - about to perform eh_action
1263 *	@link: target ATA link
1264 *	@dev: target ATA dev for per-dev action (can be NULL)
1265 *	@action: action about to be performed
1266 *
1267 *	Called just before performing EH actions to clear related bits
1268 *	in @link->eh_info such that eh actions are not unnecessarily
1269 *	repeated.
1270 *
1271 *	LOCKING:
1272 *	None.
1273 */
1274void ata_eh_about_to_do(struct ata_link *link, struct ata_device *dev,
1275			unsigned int action)
1276{
1277	struct ata_port *ap = link->ap;
1278	struct ata_eh_info *ehi = &link->eh_info;
1279	struct ata_eh_context *ehc = &link->eh_context;
1280	unsigned long flags;
1281
1282	spin_lock_irqsave(ap->lock, flags);
1283
1284	ata_eh_clear_action(link, dev, ehi, action);
1285
1286	/* About to take EH action, set RECOVERED.  Ignore actions on
1287	 * slave links as master will do them again.
1288	 */
1289	if (!(ehc->i.flags & ATA_EHI_QUIET) && link != ap->slave_link)
1290		ap->pflags |= ATA_PFLAG_RECOVERED;
1291
1292	spin_unlock_irqrestore(ap->lock, flags);
1293}
1294
1295/**
1296 *	ata_eh_done - EH action complete
1297 *	@link: ATA link for which EH actions are complete
1298 *	@dev: target ATA dev for per-dev action (can be NULL)
1299 *	@action: action just completed
1300 *
1301 *	Called right after performing EH actions to clear related bits
1302 *	in @link->eh_context.
1303 *
1304 *	LOCKING:
1305 *	None.
1306 */
1307void ata_eh_done(struct ata_link *link, struct ata_device *dev,
1308		 unsigned int action)
1309{
1310	struct ata_eh_context *ehc = &link->eh_context;
1311
1312	ata_eh_clear_action(link, dev, &ehc->i, action);
1313}
1314
1315/**
1316 *	ata_err_string - convert err_mask to descriptive string
1317 *	@err_mask: error mask to convert to string
1318 *
1319 *	Convert @err_mask to descriptive string.  Errors are
1320 *	prioritized according to severity and only the most severe
1321 *	error is reported.
1322 *
1323 *	LOCKING:
1324 *	None.
1325 *
1326 *	RETURNS:
1327 *	Descriptive string for @err_mask
1328 */
1329static const char *ata_err_string(unsigned int err_mask)
1330{
1331	if (err_mask & AC_ERR_HOST_BUS)
1332		return "host bus error";
1333	if (err_mask & AC_ERR_ATA_BUS)
1334		return "ATA bus error";
1335	if (err_mask & AC_ERR_TIMEOUT)
1336		return "timeout";
1337	if (err_mask & AC_ERR_HSM)
1338		return "HSM violation";
1339	if (err_mask & AC_ERR_SYSTEM)
1340		return "internal error";
1341	if (err_mask & AC_ERR_MEDIA)
1342		return "media error";
1343	if (err_mask & AC_ERR_INVALID)
1344		return "invalid argument";
1345	if (err_mask & AC_ERR_DEV)
1346		return "device error";
1347	if (err_mask & AC_ERR_NCQ)
1348		return "NCQ error";
1349	if (err_mask & AC_ERR_NODEV_HINT)
1350		return "Polling detection error";
1351	return "unknown error";
1352}
1353
1354/**
1355 *	atapi_eh_tur - perform ATAPI TEST_UNIT_READY
1356 *	@dev: target ATAPI device
1357 *	@r_sense_key: out parameter for sense_key
1358 *
1359 *	Perform ATAPI TEST_UNIT_READY.
1360 *
1361 *	LOCKING:
1362 *	EH context (may sleep).
1363 *
1364 *	RETURNS:
1365 *	0 on success, AC_ERR_* mask on failure.
1366 */
1367unsigned int atapi_eh_tur(struct ata_device *dev, u8 *r_sense_key)
1368{
1369	u8 cdb[ATAPI_CDB_LEN] = { TEST_UNIT_READY, 0, 0, 0, 0, 0 };
1370	struct ata_taskfile tf;
1371	unsigned int err_mask;
1372
1373	ata_tf_init(dev, &tf);
1374
1375	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1376	tf.command = ATA_CMD_PACKET;
1377	tf.protocol = ATAPI_PROT_NODATA;
1378
1379	err_mask = ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
1380	if (err_mask == AC_ERR_DEV)
1381		*r_sense_key = tf.feature >> 4;
1382	return err_mask;
1383}
1384
1385/**
1386 *	ata_eh_request_sense - perform REQUEST_SENSE_DATA_EXT
1387 *	@qc: qc to perform REQUEST_SENSE_SENSE_DATA_EXT to
1388 *	@cmd: scsi command for which the sense code should be set
1389 *
1390 *	Perform REQUEST_SENSE_DATA_EXT after the device reported CHECK
1391 *	SENSE.  This function is an EH helper.
1392 *
1393 *	LOCKING:
1394 *	Kernel thread context (may sleep).
1395 */
1396static void ata_eh_request_sense(struct ata_queued_cmd *qc,
1397				 struct scsi_cmnd *cmd)
1398{
1399	struct ata_device *dev = qc->dev;
1400	struct ata_taskfile tf;
1401	unsigned int err_mask;
1402
1403	if (qc->ap->pflags & ATA_PFLAG_FROZEN) {
1404		ata_dev_warn(dev, "sense data available but port frozen\n");
1405		return;
1406	}
1407
1408	if (!cmd || qc->flags & ATA_QCFLAG_SENSE_VALID)
1409		return;
1410
1411	if (!ata_id_sense_reporting_enabled(dev->id)) {
1412		ata_dev_warn(qc->dev, "sense data reporting disabled\n");
1413		return;
1414	}
1415
1416	DPRINTK("ATA request sense\n");
1417
1418	ata_tf_init(dev, &tf);
1419	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1420	tf.flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
1421	tf.command = ATA_CMD_REQ_SENSE_DATA;
1422	tf.protocol = ATA_PROT_NODATA;
1423
1424	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1425	/* Ignore err_mask; ATA_ERR might be set */
1426	if (tf.command & ATA_SENSE) {
1427		ata_scsi_set_sense(dev, cmd, tf.lbah, tf.lbam, tf.lbal);
1428		qc->flags |= ATA_QCFLAG_SENSE_VALID;
1429	} else {
1430		ata_dev_warn(dev, "request sense failed stat %02x emask %x\n",
1431			     tf.command, err_mask);
1432	}
1433}
1434
1435/**
1436 *	atapi_eh_request_sense - perform ATAPI REQUEST_SENSE
1437 *	@dev: device to perform REQUEST_SENSE to
1438 *	@sense_buf: result sense data buffer (SCSI_SENSE_BUFFERSIZE bytes long)
1439 *	@dfl_sense_key: default sense key to use
1440 *
1441 *	Perform ATAPI REQUEST_SENSE after the device reported CHECK
1442 *	SENSE.  This function is EH helper.
1443 *
1444 *	LOCKING:
1445 *	Kernel thread context (may sleep).
1446 *
1447 *	RETURNS:
1448 *	0 on success, AC_ERR_* mask on failure
1449 */
1450unsigned int atapi_eh_request_sense(struct ata_device *dev,
1451					   u8 *sense_buf, u8 dfl_sense_key)
1452{
1453	u8 cdb[ATAPI_CDB_LEN] =
1454		{ REQUEST_SENSE, 0, 0, 0, SCSI_SENSE_BUFFERSIZE, 0 };
1455	struct ata_port *ap = dev->link->ap;
1456	struct ata_taskfile tf;
1457
1458	DPRINTK("ATAPI request sense\n");
1459
1460	memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
1461
1462	/* initialize sense_buf with the error register,
1463	 * for the case where they are -not- overwritten
1464	 */
1465	sense_buf[0] = 0x70;
1466	sense_buf[2] = dfl_sense_key;
1467
1468	/* some devices time out if garbage left in tf */
1469	ata_tf_init(dev, &tf);
1470
1471	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1472	tf.command = ATA_CMD_PACKET;
1473
1474	/* is it pointless to prefer PIO for "safety reasons"? */
1475	if (ap->flags & ATA_FLAG_PIO_DMA) {
1476		tf.protocol = ATAPI_PROT_DMA;
1477		tf.feature |= ATAPI_PKT_DMA;
1478	} else {
1479		tf.protocol = ATAPI_PROT_PIO;
1480		tf.lbam = SCSI_SENSE_BUFFERSIZE;
1481		tf.lbah = 0;
1482	}
1483
1484	return ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
1485				 sense_buf, SCSI_SENSE_BUFFERSIZE, 0);
1486}
1487
1488/**
1489 *	ata_eh_analyze_serror - analyze SError for a failed port
1490 *	@link: ATA link to analyze SError for
1491 *
1492 *	Analyze SError if available and further determine cause of
1493 *	failure.
1494 *
1495 *	LOCKING:
1496 *	None.
1497 */
1498static void ata_eh_analyze_serror(struct ata_link *link)
1499{
1500	struct ata_eh_context *ehc = &link->eh_context;
1501	u32 serror = ehc->i.serror;
1502	unsigned int err_mask = 0, action = 0;
1503	u32 hotplug_mask;
1504
1505	if (serror & (SERR_PERSISTENT | SERR_DATA)) {
1506		err_mask |= AC_ERR_ATA_BUS;
1507		action |= ATA_EH_RESET;
1508	}
1509	if (serror & SERR_PROTOCOL) {
1510		err_mask |= AC_ERR_HSM;
1511		action |= ATA_EH_RESET;
1512	}
1513	if (serror & SERR_INTERNAL) {
1514		err_mask |= AC_ERR_SYSTEM;
1515		action |= ATA_EH_RESET;
1516	}
1517
1518	/* Determine whether a hotplug event has occurred.  Both
1519	 * SError.N/X are considered hotplug events for enabled or
1520	 * host links.  For disabled PMP links, only N bit is
1521	 * considered as X bit is left at 1 for link plugging.
1522	 */
1523	if (link->lpm_policy > ATA_LPM_MAX_POWER)
1524		hotplug_mask = 0;	/* hotplug doesn't work w/ LPM */
1525	else if (!(link->flags & ATA_LFLAG_DISABLED) || ata_is_host_link(link))
1526		hotplug_mask = SERR_PHYRDY_CHG | SERR_DEV_XCHG;
1527	else
1528		hotplug_mask = SERR_PHYRDY_CHG;
1529
1530	if (serror & hotplug_mask)
1531		ata_ehi_hotplugged(&ehc->i);
1532
1533	ehc->i.err_mask |= err_mask;
1534	ehc->i.action |= action;
1535}
1536
1537/**
1538 *	ata_eh_analyze_tf - analyze taskfile of a failed qc
1539 *	@qc: qc to analyze
1540 *	@tf: Taskfile registers to analyze
1541 *
1542 *	Analyze taskfile of @qc and further determine cause of
1543 *	failure.  This function also requests ATAPI sense data if
1544 *	available.
1545 *
1546 *	LOCKING:
1547 *	Kernel thread context (may sleep).
1548 *
1549 *	RETURNS:
1550 *	Determined recovery action
1551 */
1552static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc,
1553				      const struct ata_taskfile *tf)
1554{
1555	unsigned int tmp, action = 0;
1556	u8 stat = tf->command, err = tf->feature;
1557
1558	if ((stat & (ATA_BUSY | ATA_DRQ | ATA_DRDY)) != ATA_DRDY) {
1559		qc->err_mask |= AC_ERR_HSM;
1560		return ATA_EH_RESET;
1561	}
1562
1563	if (stat & (ATA_ERR | ATA_DF)) {
1564		qc->err_mask |= AC_ERR_DEV;
1565		/*
1566		 * Sense data reporting does not work if the
1567		 * device fault bit is set.
1568		 */
1569		if (stat & ATA_DF)
1570			stat &= ~ATA_SENSE;
1571	} else {
1572		return 0;
1573	}
1574
1575	switch (qc->dev->class) {
1576	case ATA_DEV_ZAC:
1577		if (stat & ATA_SENSE)
1578			ata_eh_request_sense(qc, qc->scsicmd);
1579		fallthrough;
1580	case ATA_DEV_ATA:
1581		if (err & ATA_ICRC)
1582			qc->err_mask |= AC_ERR_ATA_BUS;
1583		if (err & (ATA_UNC | ATA_AMNF))
1584			qc->err_mask |= AC_ERR_MEDIA;
1585		if (err & ATA_IDNF)
1586			qc->err_mask |= AC_ERR_INVALID;
1587		break;
1588
1589	case ATA_DEV_ATAPI:
1590		if (!(qc->ap->pflags & ATA_PFLAG_FROZEN)) {
1591			tmp = atapi_eh_request_sense(qc->dev,
1592						qc->scsicmd->sense_buffer,
1593						qc->result_tf.feature >> 4);
1594			if (!tmp)
1595				qc->flags |= ATA_QCFLAG_SENSE_VALID;
1596			else
1597				qc->err_mask |= tmp;
1598		}
1599	}
1600
1601	if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
1602		int ret = scsi_check_sense(qc->scsicmd);
1603		/*
1604		 * SUCCESS here means that the sense code could be
1605		 * evaluated and should be passed to the upper layers
1606		 * for correct evaluation.
1607		 * FAILED means the sense code could not be interpreted
1608		 * and the device would need to be reset.
1609		 * NEEDS_RETRY and ADD_TO_MLQUEUE means that the
1610		 * command would need to be retried.
1611		 */
1612		if (ret == NEEDS_RETRY || ret == ADD_TO_MLQUEUE) {
1613			qc->flags |= ATA_QCFLAG_RETRY;
1614			qc->err_mask |= AC_ERR_OTHER;
1615		} else if (ret != SUCCESS) {
1616			qc->err_mask |= AC_ERR_HSM;
1617		}
1618	}
1619	if (qc->err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT | AC_ERR_ATA_BUS))
1620		action |= ATA_EH_RESET;
1621
1622	return action;
1623}
1624
1625static int ata_eh_categorize_error(unsigned int eflags, unsigned int err_mask,
1626				   int *xfer_ok)
1627{
1628	int base = 0;
1629
1630	if (!(eflags & ATA_EFLAG_DUBIOUS_XFER))
1631		*xfer_ok = 1;
1632
1633	if (!*xfer_ok)
1634		base = ATA_ECAT_DUBIOUS_NONE;
1635
1636	if (err_mask & AC_ERR_ATA_BUS)
1637		return base + ATA_ECAT_ATA_BUS;
1638
1639	if (err_mask & AC_ERR_TIMEOUT)
1640		return base + ATA_ECAT_TOUT_HSM;
1641
1642	if (eflags & ATA_EFLAG_IS_IO) {
1643		if (err_mask & AC_ERR_HSM)
1644			return base + ATA_ECAT_TOUT_HSM;
1645		if ((err_mask &
1646		     (AC_ERR_DEV|AC_ERR_MEDIA|AC_ERR_INVALID)) == AC_ERR_DEV)
1647			return base + ATA_ECAT_UNK_DEV;
1648	}
1649
1650	return 0;
1651}
1652
1653struct speed_down_verdict_arg {
1654	u64 since;
1655	int xfer_ok;
1656	int nr_errors[ATA_ECAT_NR];
1657};
1658
1659static int speed_down_verdict_cb(struct ata_ering_entry *ent, void *void_arg)
1660{
1661	struct speed_down_verdict_arg *arg = void_arg;
1662	int cat;
1663
1664	if ((ent->eflags & ATA_EFLAG_OLD_ER) || (ent->timestamp < arg->since))
1665		return -1;
1666
1667	cat = ata_eh_categorize_error(ent->eflags, ent->err_mask,
1668				      &arg->xfer_ok);
1669	arg->nr_errors[cat]++;
1670
1671	return 0;
1672}
1673
1674/**
1675 *	ata_eh_speed_down_verdict - Determine speed down verdict
1676 *	@dev: Device of interest
1677 *
1678 *	This function examines error ring of @dev and determines
1679 *	whether NCQ needs to be turned off, transfer speed should be
1680 *	stepped down, or falling back to PIO is necessary.
1681 *
1682 *	ECAT_ATA_BUS	: ATA_BUS error for any command
1683 *
1684 *	ECAT_TOUT_HSM	: TIMEOUT for any command or HSM violation for
1685 *			  IO commands
1686 *
1687 *	ECAT_UNK_DEV	: Unknown DEV error for IO commands
1688 *
1689 *	ECAT_DUBIOUS_*	: Identical to above three but occurred while
1690 *			  data transfer hasn't been verified.
1691 *
1692 *	Verdicts are
1693 *
1694 *	NCQ_OFF		: Turn off NCQ.
1695 *
1696 *	SPEED_DOWN	: Speed down transfer speed but don't fall back
1697 *			  to PIO.
1698 *
1699 *	FALLBACK_TO_PIO	: Fall back to PIO.
1700 *
1701 *	Even if multiple verdicts are returned, only one action is
1702 *	taken per error.  An action triggered by non-DUBIOUS errors
1703 *	clears ering, while one triggered by DUBIOUS_* errors doesn't.
1704 *	This is to expedite speed down decisions right after device is
1705 *	initially configured.
1706 *
1707 *	The following are speed down rules.  #1 and #2 deal with
1708 *	DUBIOUS errors.
1709 *
1710 *	1. If more than one DUBIOUS_ATA_BUS or DUBIOUS_TOUT_HSM errors
1711 *	   occurred during last 5 mins, SPEED_DOWN and FALLBACK_TO_PIO.
1712 *
1713 *	2. If more than one DUBIOUS_TOUT_HSM or DUBIOUS_UNK_DEV errors
1714 *	   occurred during last 5 mins, NCQ_OFF.
1715 *
1716 *	3. If more than 8 ATA_BUS, TOUT_HSM or UNK_DEV errors
1717 *	   occurred during last 5 mins, FALLBACK_TO_PIO
1718 *
1719 *	4. If more than 3 TOUT_HSM or UNK_DEV errors occurred
1720 *	   during last 10 mins, NCQ_OFF.
1721 *
1722 *	5. If more than 3 ATA_BUS or TOUT_HSM errors, or more than 6
1723 *	   UNK_DEV errors occurred during last 10 mins, SPEED_DOWN.
1724 *
1725 *	LOCKING:
1726 *	Inherited from caller.
1727 *
1728 *	RETURNS:
1729 *	OR of ATA_EH_SPDN_* flags.
1730 */
1731static unsigned int ata_eh_speed_down_verdict(struct ata_device *dev)
1732{
1733	const u64 j5mins = 5LLU * 60 * HZ, j10mins = 10LLU * 60 * HZ;
1734	u64 j64 = get_jiffies_64();
1735	struct speed_down_verdict_arg arg;
1736	unsigned int verdict = 0;
1737
1738	/* scan past 5 mins of error history */
1739	memset(&arg, 0, sizeof(arg));
1740	arg.since = j64 - min(j64, j5mins);
1741	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1742
1743	if (arg.nr_errors[ATA_ECAT_DUBIOUS_ATA_BUS] +
1744	    arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] > 1)
1745		verdict |= ATA_EH_SPDN_SPEED_DOWN |
1746			ATA_EH_SPDN_FALLBACK_TO_PIO | ATA_EH_SPDN_KEEP_ERRORS;
1747
1748	if (arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] +
1749	    arg.nr_errors[ATA_ECAT_DUBIOUS_UNK_DEV] > 1)
1750		verdict |= ATA_EH_SPDN_NCQ_OFF | ATA_EH_SPDN_KEEP_ERRORS;
1751
1752	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1753	    arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1754	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1755		verdict |= ATA_EH_SPDN_FALLBACK_TO_PIO;
1756
1757	/* scan past 10 mins of error history */
1758	memset(&arg, 0, sizeof(arg));
1759	arg.since = j64 - min(j64, j10mins);
1760	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1761
1762	if (arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1763	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 3)
1764		verdict |= ATA_EH_SPDN_NCQ_OFF;
1765
1766	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1767	    arg.nr_errors[ATA_ECAT_TOUT_HSM] > 3 ||
1768	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1769		verdict |= ATA_EH_SPDN_SPEED_DOWN;
1770
1771	return verdict;
1772}
1773
1774/**
1775 *	ata_eh_speed_down - record error and speed down if necessary
1776 *	@dev: Failed device
1777 *	@eflags: mask of ATA_EFLAG_* flags
1778 *	@err_mask: err_mask of the error
1779 *
1780 *	Record error and examine error history to determine whether
1781 *	adjusting transmission speed is necessary.  It also sets
1782 *	transmission limits appropriately if such adjustment is
1783 *	necessary.
1784 *
1785 *	LOCKING:
1786 *	Kernel thread context (may sleep).
1787 *
1788 *	RETURNS:
1789 *	Determined recovery action.
1790 */
1791static unsigned int ata_eh_speed_down(struct ata_device *dev,
1792				unsigned int eflags, unsigned int err_mask)
1793{
1794	struct ata_link *link = ata_dev_phys_link(dev);
1795	int xfer_ok = 0;
1796	unsigned int verdict;
1797	unsigned int action = 0;
1798
1799	/* don't bother if Cat-0 error */
1800	if (ata_eh_categorize_error(eflags, err_mask, &xfer_ok) == 0)
1801		return 0;
1802
1803	/* record error and determine whether speed down is necessary */
1804	ata_ering_record(&dev->ering, eflags, err_mask);
1805	verdict = ata_eh_speed_down_verdict(dev);
1806
1807	/* turn off NCQ? */
1808	if ((verdict & ATA_EH_SPDN_NCQ_OFF) &&
1809	    (dev->flags & (ATA_DFLAG_PIO | ATA_DFLAG_NCQ |
1810			   ATA_DFLAG_NCQ_OFF)) == ATA_DFLAG_NCQ) {
1811		dev->flags |= ATA_DFLAG_NCQ_OFF;
1812		ata_dev_warn(dev, "NCQ disabled due to excessive errors\n");
1813		goto done;
1814	}
1815
1816	/* speed down? */
1817	if (verdict & ATA_EH_SPDN_SPEED_DOWN) {
1818		/* speed down SATA link speed if possible */
1819		if (sata_down_spd_limit(link, 0) == 0) {
1820			action |= ATA_EH_RESET;
1821			goto done;
1822		}
1823
1824		/* lower transfer mode */
1825		if (dev->spdn_cnt < 2) {
1826			static const int dma_dnxfer_sel[] =
1827				{ ATA_DNXFER_DMA, ATA_DNXFER_40C };
1828			static const int pio_dnxfer_sel[] =
1829				{ ATA_DNXFER_PIO, ATA_DNXFER_FORCE_PIO0 };
1830			int sel;
1831
1832			if (dev->xfer_shift != ATA_SHIFT_PIO)
1833				sel = dma_dnxfer_sel[dev->spdn_cnt];
1834			else
1835				sel = pio_dnxfer_sel[dev->spdn_cnt];
1836
1837			dev->spdn_cnt++;
1838
1839			if (ata_down_xfermask_limit(dev, sel) == 0) {
1840				action |= ATA_EH_RESET;
1841				goto done;
1842			}
1843		}
1844	}
1845
1846	/* Fall back to PIO?  Slowing down to PIO is meaningless for
1847	 * SATA ATA devices.  Consider it only for PATA and SATAPI.
1848	 */
1849	if ((verdict & ATA_EH_SPDN_FALLBACK_TO_PIO) && (dev->spdn_cnt >= 2) &&
1850	    (link->ap->cbl != ATA_CBL_SATA || dev->class == ATA_DEV_ATAPI) &&
1851	    (dev->xfer_shift != ATA_SHIFT_PIO)) {
1852		if (ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO) == 0) {
1853			dev->spdn_cnt = 0;
1854			action |= ATA_EH_RESET;
1855			goto done;
1856		}
1857	}
1858
1859	return 0;
1860 done:
1861	/* device has been slowed down, blow error history */
1862	if (!(verdict & ATA_EH_SPDN_KEEP_ERRORS))
1863		ata_ering_clear(&dev->ering);
1864	return action;
1865}
1866
1867/**
1868 *	ata_eh_worth_retry - analyze error and decide whether to retry
1869 *	@qc: qc to possibly retry
1870 *
1871 *	Look at the cause of the error and decide if a retry
1872 * 	might be useful or not.  We don't want to retry media errors
1873 *	because the drive itself has probably already taken 10-30 seconds
1874 *	doing its own internal retries before reporting the failure.
1875 */
1876static inline int ata_eh_worth_retry(struct ata_queued_cmd *qc)
1877{
1878	if (qc->err_mask & AC_ERR_MEDIA)
1879		return 0;	/* don't retry media errors */
1880	if (qc->flags & ATA_QCFLAG_IO)
1881		return 1;	/* otherwise retry anything from fs stack */
1882	if (qc->err_mask & AC_ERR_INVALID)
1883		return 0;	/* don't retry these */
1884	return qc->err_mask != AC_ERR_DEV;  /* retry if not dev error */
1885}
1886
1887/**
1888 *      ata_eh_quiet - check if we need to be quiet about a command error
1889 *      @qc: qc to check
1890 *
1891 *      Look at the qc flags anbd its scsi command request flags to determine
1892 *      if we need to be quiet about the command failure.
1893 */
1894static inline bool ata_eh_quiet(struct ata_queued_cmd *qc)
1895{
1896	if (qc->scsicmd &&
1897	    qc->scsicmd->request->rq_flags & RQF_QUIET)
1898		qc->flags |= ATA_QCFLAG_QUIET;
1899	return qc->flags & ATA_QCFLAG_QUIET;
1900}
1901
1902/**
1903 *	ata_eh_link_autopsy - analyze error and determine recovery action
1904 *	@link: host link to perform autopsy on
1905 *
1906 *	Analyze why @link failed and determine which recovery actions
1907 *	are needed.  This function also sets more detailed AC_ERR_*
1908 *	values and fills sense data for ATAPI CHECK SENSE.
1909 *
1910 *	LOCKING:
1911 *	Kernel thread context (may sleep).
1912 */
1913static void ata_eh_link_autopsy(struct ata_link *link)
1914{
1915	struct ata_port *ap = link->ap;
1916	struct ata_eh_context *ehc = &link->eh_context;
1917	struct ata_queued_cmd *qc;
1918	struct ata_device *dev;
1919	unsigned int all_err_mask = 0, eflags = 0;
1920	int tag, nr_failed = 0, nr_quiet = 0;
1921	u32 serror;
1922	int rc;
1923
1924	DPRINTK("ENTER\n");
1925
1926	if (ehc->i.flags & ATA_EHI_NO_AUTOPSY)
1927		return;
1928
1929	/* obtain and analyze SError */
1930	rc = sata_scr_read(link, SCR_ERROR, &serror);
1931	if (rc == 0) {
1932		ehc->i.serror |= serror;
1933		ata_eh_analyze_serror(link);
1934	} else if (rc != -EOPNOTSUPP) {
1935		/* SError read failed, force reset and probing */
1936		ehc->i.probe_mask |= ATA_ALL_DEVICES;
1937		ehc->i.action |= ATA_EH_RESET;
1938		ehc->i.err_mask |= AC_ERR_OTHER;
1939	}
1940
1941	/* analyze NCQ failure */
1942	ata_eh_analyze_ncq_error(link);
1943
1944	/* any real error trumps AC_ERR_OTHER */
1945	if (ehc->i.err_mask & ~AC_ERR_OTHER)
1946		ehc->i.err_mask &= ~AC_ERR_OTHER;
1947
1948	all_err_mask |= ehc->i.err_mask;
1949
1950	ata_qc_for_each_raw(ap, qc, tag) {
1951		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
1952		    ata_dev_phys_link(qc->dev) != link)
1953			continue;
1954
1955		/* inherit upper level err_mask */
1956		qc->err_mask |= ehc->i.err_mask;
1957
1958		/* analyze TF */
1959		ehc->i.action |= ata_eh_analyze_tf(qc, &qc->result_tf);
1960
1961		/* DEV errors are probably spurious in case of ATA_BUS error */
1962		if (qc->err_mask & AC_ERR_ATA_BUS)
1963			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_MEDIA |
1964					  AC_ERR_INVALID);
1965
1966		/* any real error trumps unknown error */
1967		if (qc->err_mask & ~AC_ERR_OTHER)
1968			qc->err_mask &= ~AC_ERR_OTHER;
1969
1970		/*
1971		 * SENSE_VALID trumps dev/unknown error and revalidation. Upper
1972		 * layers will determine whether the command is worth retrying
1973		 * based on the sense data and device class/type. Otherwise,
1974		 * determine directly if the command is worth retrying using its
1975		 * error mask and flags.
1976		 */
1977		if (qc->flags & ATA_QCFLAG_SENSE_VALID)
1978			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_OTHER);
1979		else if (ata_eh_worth_retry(qc))
1980			qc->flags |= ATA_QCFLAG_RETRY;
1981
1982		/* accumulate error info */
1983		ehc->i.dev = qc->dev;
1984		all_err_mask |= qc->err_mask;
1985		if (qc->flags & ATA_QCFLAG_IO)
1986			eflags |= ATA_EFLAG_IS_IO;
1987		trace_ata_eh_link_autopsy_qc(qc);
1988
1989		/* Count quiet errors */
1990		if (ata_eh_quiet(qc))
1991			nr_quiet++;
1992		nr_failed++;
1993	}
1994
1995	/* If all failed commands requested silence, then be quiet */
1996	if (nr_quiet == nr_failed)
1997		ehc->i.flags |= ATA_EHI_QUIET;
1998
1999	/* enforce default EH actions */
2000	if (ap->pflags & ATA_PFLAG_FROZEN ||
2001	    all_err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT))
2002		ehc->i.action |= ATA_EH_RESET;
2003	else if (((eflags & ATA_EFLAG_IS_IO) && all_err_mask) ||
2004		 (!(eflags & ATA_EFLAG_IS_IO) && (all_err_mask & ~AC_ERR_DEV)))
2005		ehc->i.action |= ATA_EH_REVALIDATE;
2006
2007	/* If we have offending qcs and the associated failed device,
2008	 * perform per-dev EH action only on the offending device.
2009	 */
2010	if (ehc->i.dev) {
2011		ehc->i.dev_action[ehc->i.dev->devno] |=
2012			ehc->i.action & ATA_EH_PERDEV_MASK;
2013		ehc->i.action &= ~ATA_EH_PERDEV_MASK;
2014	}
2015
2016	/* propagate timeout to host link */
2017	if ((all_err_mask & AC_ERR_TIMEOUT) && !ata_is_host_link(link))
2018		ap->link.eh_context.i.err_mask |= AC_ERR_TIMEOUT;
2019
2020	/* record error and consider speeding down */
2021	dev = ehc->i.dev;
2022	if (!dev && ((ata_link_max_devices(link) == 1 &&
2023		      ata_dev_enabled(link->device))))
2024	    dev = link->device;
2025
2026	if (dev) {
2027		if (dev->flags & ATA_DFLAG_DUBIOUS_XFER)
2028			eflags |= ATA_EFLAG_DUBIOUS_XFER;
2029		ehc->i.action |= ata_eh_speed_down(dev, eflags, all_err_mask);
2030		trace_ata_eh_link_autopsy(dev, ehc->i.action, all_err_mask);
2031	}
2032	DPRINTK("EXIT\n");
2033}
2034
2035/**
2036 *	ata_eh_autopsy - analyze error and determine recovery action
2037 *	@ap: host port to perform autopsy on
2038 *
2039 *	Analyze all links of @ap and determine why they failed and
2040 *	which recovery actions are needed.
2041 *
2042 *	LOCKING:
2043 *	Kernel thread context (may sleep).
2044 */
2045void ata_eh_autopsy(struct ata_port *ap)
2046{
2047	struct ata_link *link;
2048
2049	ata_for_each_link(link, ap, EDGE)
2050		ata_eh_link_autopsy(link);
2051
2052	/* Handle the frigging slave link.  Autopsy is done similarly
2053	 * but actions and flags are transferred over to the master
2054	 * link and handled from there.
2055	 */
2056	if (ap->slave_link) {
2057		struct ata_eh_context *mehc = &ap->link.eh_context;
2058		struct ata_eh_context *sehc = &ap->slave_link->eh_context;
2059
2060		/* transfer control flags from master to slave */
2061		sehc->i.flags |= mehc->i.flags & ATA_EHI_TO_SLAVE_MASK;
2062
2063		/* perform autopsy on the slave link */
2064		ata_eh_link_autopsy(ap->slave_link);
2065
2066		/* transfer actions from slave to master and clear slave */
2067		ata_eh_about_to_do(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2068		mehc->i.action		|= sehc->i.action;
2069		mehc->i.dev_action[1]	|= sehc->i.dev_action[1];
2070		mehc->i.flags		|= sehc->i.flags;
2071		ata_eh_done(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2072	}
2073
2074	/* Autopsy of fanout ports can affect host link autopsy.
2075	 * Perform host link autopsy last.
2076	 */
2077	if (sata_pmp_attached(ap))
2078		ata_eh_link_autopsy(&ap->link);
2079}
2080
2081/**
2082 *	ata_get_cmd_descript - get description for ATA command
2083 *	@command: ATA command code to get description for
2084 *
2085 *	Return a textual description of the given command, or NULL if the
2086 *	command is not known.
2087 *
2088 *	LOCKING:
2089 *	None
2090 */
2091const char *ata_get_cmd_descript(u8 command)
2092{
2093#ifdef CONFIG_ATA_VERBOSE_ERROR
2094	static const struct
2095	{
2096		u8 command;
2097		const char *text;
2098	} cmd_descr[] = {
2099		{ ATA_CMD_DEV_RESET,		"DEVICE RESET" },
2100		{ ATA_CMD_CHK_POWER,		"CHECK POWER MODE" },
2101		{ ATA_CMD_STANDBY,		"STANDBY" },
2102		{ ATA_CMD_IDLE,			"IDLE" },
2103		{ ATA_CMD_EDD,			"EXECUTE DEVICE DIAGNOSTIC" },
2104		{ ATA_CMD_DOWNLOAD_MICRO,	"DOWNLOAD MICROCODE" },
2105		{ ATA_CMD_DOWNLOAD_MICRO_DMA,	"DOWNLOAD MICROCODE DMA" },
2106		{ ATA_CMD_NOP,			"NOP" },
2107		{ ATA_CMD_FLUSH,		"FLUSH CACHE" },
2108		{ ATA_CMD_FLUSH_EXT,		"FLUSH CACHE EXT" },
2109		{ ATA_CMD_ID_ATA,		"IDENTIFY DEVICE" },
2110		{ ATA_CMD_ID_ATAPI,		"IDENTIFY PACKET DEVICE" },
2111		{ ATA_CMD_SERVICE,		"SERVICE" },
2112		{ ATA_CMD_READ,			"READ DMA" },
2113		{ ATA_CMD_READ_EXT,		"READ DMA EXT" },
2114		{ ATA_CMD_READ_QUEUED,		"READ DMA QUEUED" },
2115		{ ATA_CMD_READ_STREAM_EXT,	"READ STREAM EXT" },
2116		{ ATA_CMD_READ_STREAM_DMA_EXT,  "READ STREAM DMA EXT" },
2117		{ ATA_CMD_WRITE,		"WRITE DMA" },
2118		{ ATA_CMD_WRITE_EXT,		"WRITE DMA EXT" },
2119		{ ATA_CMD_WRITE_QUEUED,		"WRITE DMA QUEUED EXT" },
2120		{ ATA_CMD_WRITE_STREAM_EXT,	"WRITE STREAM EXT" },
2121		{ ATA_CMD_WRITE_STREAM_DMA_EXT, "WRITE STREAM DMA EXT" },
2122		{ ATA_CMD_WRITE_FUA_EXT,	"WRITE DMA FUA EXT" },
2123		{ ATA_CMD_WRITE_QUEUED_FUA_EXT, "WRITE DMA QUEUED FUA EXT" },
2124		{ ATA_CMD_FPDMA_READ,		"READ FPDMA QUEUED" },
2125		{ ATA_CMD_FPDMA_WRITE,		"WRITE FPDMA QUEUED" },
2126		{ ATA_CMD_FPDMA_SEND,		"SEND FPDMA QUEUED" },
2127		{ ATA_CMD_FPDMA_RECV,		"RECEIVE FPDMA QUEUED" },
2128		{ ATA_CMD_PIO_READ,		"READ SECTOR(S)" },
2129		{ ATA_CMD_PIO_READ_EXT,		"READ SECTOR(S) EXT" },
2130		{ ATA_CMD_PIO_WRITE,		"WRITE SECTOR(S)" },
2131		{ ATA_CMD_PIO_WRITE_EXT,	"WRITE SECTOR(S) EXT" },
2132		{ ATA_CMD_READ_MULTI,		"READ MULTIPLE" },
2133		{ ATA_CMD_READ_MULTI_EXT,	"READ MULTIPLE EXT" },
2134		{ ATA_CMD_WRITE_MULTI,		"WRITE MULTIPLE" },
2135		{ ATA_CMD_WRITE_MULTI_EXT,	"WRITE MULTIPLE EXT" },
2136		{ ATA_CMD_WRITE_MULTI_FUA_EXT,	"WRITE MULTIPLE FUA EXT" },
2137		{ ATA_CMD_SET_FEATURES,		"SET FEATURES" },
2138		{ ATA_CMD_SET_MULTI,		"SET MULTIPLE MODE" },
2139		{ ATA_CMD_VERIFY,		"READ VERIFY SECTOR(S)" },
2140		{ ATA_CMD_VERIFY_EXT,		"READ VERIFY SECTOR(S) EXT" },
2141		{ ATA_CMD_WRITE_UNCORR_EXT,	"WRITE UNCORRECTABLE EXT" },
2142		{ ATA_CMD_STANDBYNOW1,		"STANDBY IMMEDIATE" },
2143		{ ATA_CMD_IDLEIMMEDIATE,	"IDLE IMMEDIATE" },
2144		{ ATA_CMD_SLEEP,		"SLEEP" },
2145		{ ATA_CMD_INIT_DEV_PARAMS,	"INITIALIZE DEVICE PARAMETERS" },
2146		{ ATA_CMD_READ_NATIVE_MAX,	"READ NATIVE MAX ADDRESS" },
2147		{ ATA_CMD_READ_NATIVE_MAX_EXT,	"READ NATIVE MAX ADDRESS EXT" },
2148		{ ATA_CMD_SET_MAX,		"SET MAX ADDRESS" },
2149		{ ATA_CMD_SET_MAX_EXT,		"SET MAX ADDRESS EXT" },
2150		{ ATA_CMD_READ_LOG_EXT,		"READ LOG EXT" },
2151		{ ATA_CMD_WRITE_LOG_EXT,	"WRITE LOG EXT" },
2152		{ ATA_CMD_READ_LOG_DMA_EXT,	"READ LOG DMA EXT" },
2153		{ ATA_CMD_WRITE_LOG_DMA_EXT,	"WRITE LOG DMA EXT" },
2154		{ ATA_CMD_TRUSTED_NONDATA,	"TRUSTED NON-DATA" },
2155		{ ATA_CMD_TRUSTED_RCV,		"TRUSTED RECEIVE" },
2156		{ ATA_CMD_TRUSTED_RCV_DMA,	"TRUSTED RECEIVE DMA" },
2157		{ ATA_CMD_TRUSTED_SND,		"TRUSTED SEND" },
2158		{ ATA_CMD_TRUSTED_SND_DMA,	"TRUSTED SEND DMA" },
2159		{ ATA_CMD_PMP_READ,		"READ BUFFER" },
2160		{ ATA_CMD_PMP_READ_DMA,		"READ BUFFER DMA" },
2161		{ ATA_CMD_PMP_WRITE,		"WRITE BUFFER" },
2162		{ ATA_CMD_PMP_WRITE_DMA,	"WRITE BUFFER DMA" },
2163		{ ATA_CMD_CONF_OVERLAY,		"DEVICE CONFIGURATION OVERLAY" },
2164		{ ATA_CMD_SEC_SET_PASS,		"SECURITY SET PASSWORD" },
2165		{ ATA_CMD_SEC_UNLOCK,		"SECURITY UNLOCK" },
2166		{ ATA_CMD_SEC_ERASE_PREP,	"SECURITY ERASE PREPARE" },
2167		{ ATA_CMD_SEC_ERASE_UNIT,	"SECURITY ERASE UNIT" },
2168		{ ATA_CMD_SEC_FREEZE_LOCK,	"SECURITY FREEZE LOCK" },
2169		{ ATA_CMD_SEC_DISABLE_PASS,	"SECURITY DISABLE PASSWORD" },
2170		{ ATA_CMD_CONFIG_STREAM,	"CONFIGURE STREAM" },
2171		{ ATA_CMD_SMART,		"SMART" },
2172		{ ATA_CMD_MEDIA_LOCK,		"DOOR LOCK" },
2173		{ ATA_CMD_MEDIA_UNLOCK,		"DOOR UNLOCK" },
2174		{ ATA_CMD_DSM,			"DATA SET MANAGEMENT" },
2175		{ ATA_CMD_CHK_MED_CRD_TYP,	"CHECK MEDIA CARD TYPE" },
2176		{ ATA_CMD_CFA_REQ_EXT_ERR,	"CFA REQUEST EXTENDED ERROR" },
2177		{ ATA_CMD_CFA_WRITE_NE,		"CFA WRITE SECTORS WITHOUT ERASE" },
2178		{ ATA_CMD_CFA_TRANS_SECT,	"CFA TRANSLATE SECTOR" },
2179		{ ATA_CMD_CFA_ERASE,		"CFA ERASE SECTORS" },
2180		{ ATA_CMD_CFA_WRITE_MULT_NE,	"CFA WRITE MULTIPLE WITHOUT ERASE" },
2181		{ ATA_CMD_REQ_SENSE_DATA,	"REQUEST SENSE DATA EXT" },
2182		{ ATA_CMD_SANITIZE_DEVICE,	"SANITIZE DEVICE" },
2183		{ ATA_CMD_ZAC_MGMT_IN,		"ZAC MANAGEMENT IN" },
2184		{ ATA_CMD_ZAC_MGMT_OUT,		"ZAC MANAGEMENT OUT" },
2185		{ ATA_CMD_READ_LONG,		"READ LONG (with retries)" },
2186		{ ATA_CMD_READ_LONG_ONCE,	"READ LONG (without retries)" },
2187		{ ATA_CMD_WRITE_LONG,		"WRITE LONG (with retries)" },
2188		{ ATA_CMD_WRITE_LONG_ONCE,	"WRITE LONG (without retries)" },
2189		{ ATA_CMD_RESTORE,		"RECALIBRATE" },
2190		{ 0,				NULL } /* terminate list */
2191	};
2192
2193	unsigned int i;
2194	for (i = 0; cmd_descr[i].text; i++)
2195		if (cmd_descr[i].command == command)
2196			return cmd_descr[i].text;
2197#endif
2198
2199	return NULL;
2200}
2201EXPORT_SYMBOL_GPL(ata_get_cmd_descript);
2202
2203/**
2204 *	ata_eh_link_report - report error handling to user
2205 *	@link: ATA link EH is going on
2206 *
2207 *	Report EH to user.
2208 *
2209 *	LOCKING:
2210 *	None.
2211 */
2212static void ata_eh_link_report(struct ata_link *link)
2213{
2214	struct ata_port *ap = link->ap;
2215	struct ata_eh_context *ehc = &link->eh_context;
2216	struct ata_queued_cmd *qc;
2217	const char *frozen, *desc;
2218	char tries_buf[6] = "";
2219	int tag, nr_failed = 0;
2220
2221	if (ehc->i.flags & ATA_EHI_QUIET)
2222		return;
2223
2224	desc = NULL;
2225	if (ehc->i.desc[0] != '\0')
2226		desc = ehc->i.desc;
2227
2228	ata_qc_for_each_raw(ap, qc, tag) {
2229		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2230		    ata_dev_phys_link(qc->dev) != link ||
2231		    ((qc->flags & ATA_QCFLAG_QUIET) &&
2232		     qc->err_mask == AC_ERR_DEV))
2233			continue;
2234		if (qc->flags & ATA_QCFLAG_SENSE_VALID && !qc->err_mask)
2235			continue;
2236
2237		nr_failed++;
2238	}
2239
2240	if (!nr_failed && !ehc->i.err_mask)
2241		return;
2242
2243	frozen = "";
2244	if (ap->pflags & ATA_PFLAG_FROZEN)
2245		frozen = " frozen";
2246
2247	if (ap->eh_tries < ATA_EH_MAX_TRIES)
2248		snprintf(tries_buf, sizeof(tries_buf), " t%d",
2249			 ap->eh_tries);
2250
2251	if (ehc->i.dev) {
2252		ata_dev_err(ehc->i.dev, "exception Emask 0x%x "
2253			    "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2254			    ehc->i.err_mask, link->sactive, ehc->i.serror,
2255			    ehc->i.action, frozen, tries_buf);
2256		if (desc)
2257			ata_dev_err(ehc->i.dev, "%s\n", desc);
2258	} else {
2259		ata_link_err(link, "exception Emask 0x%x "
2260			     "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2261			     ehc->i.err_mask, link->sactive, ehc->i.serror,
2262			     ehc->i.action, frozen, tries_buf);
2263		if (desc)
2264			ata_link_err(link, "%s\n", desc);
2265	}
2266
2267#ifdef CONFIG_ATA_VERBOSE_ERROR
2268	if (ehc->i.serror)
2269		ata_link_err(link,
2270		  "SError: { %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s}\n",
2271		  ehc->i.serror & SERR_DATA_RECOVERED ? "RecovData " : "",
2272		  ehc->i.serror & SERR_COMM_RECOVERED ? "RecovComm " : "",
2273		  ehc->i.serror & SERR_DATA ? "UnrecovData " : "",
2274		  ehc->i.serror & SERR_PERSISTENT ? "Persist " : "",
2275		  ehc->i.serror & SERR_PROTOCOL ? "Proto " : "",
2276		  ehc->i.serror & SERR_INTERNAL ? "HostInt " : "",
2277		  ehc->i.serror & SERR_PHYRDY_CHG ? "PHYRdyChg " : "",
2278		  ehc->i.serror & SERR_PHY_INT_ERR ? "PHYInt " : "",
2279		  ehc->i.serror & SERR_COMM_WAKE ? "CommWake " : "",
2280		  ehc->i.serror & SERR_10B_8B_ERR ? "10B8B " : "",
2281		  ehc->i.serror & SERR_DISPARITY ? "Dispar " : "",
2282		  ehc->i.serror & SERR_CRC ? "BadCRC " : "",
2283		  ehc->i.serror & SERR_HANDSHAKE ? "Handshk " : "",
2284		  ehc->i.serror & SERR_LINK_SEQ_ERR ? "LinkSeq " : "",
2285		  ehc->i.serror & SERR_TRANS_ST_ERROR ? "TrStaTrns " : "",
2286		  ehc->i.serror & SERR_UNRECOG_FIS ? "UnrecFIS " : "",
2287		  ehc->i.serror & SERR_DEV_XCHG ? "DevExch " : "");
2288#endif
2289
2290	ata_qc_for_each_raw(ap, qc, tag) {
2291		struct ata_taskfile *cmd = &qc->tf, *res = &qc->result_tf;
2292		char data_buf[20] = "";
2293		char cdb_buf[70] = "";
2294
2295		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2296		    ata_dev_phys_link(qc->dev) != link || !qc->err_mask)
2297			continue;
2298
2299		if (qc->dma_dir != DMA_NONE) {
2300			static const char *dma_str[] = {
2301				[DMA_BIDIRECTIONAL]	= "bidi",
2302				[DMA_TO_DEVICE]		= "out",
2303				[DMA_FROM_DEVICE]	= "in",
2304			};
2305			const char *prot_str = NULL;
2306
2307			switch (qc->tf.protocol) {
2308			case ATA_PROT_UNKNOWN:
2309				prot_str = "unknown";
2310				break;
2311			case ATA_PROT_NODATA:
2312				prot_str = "nodata";
2313				break;
2314			case ATA_PROT_PIO:
2315				prot_str = "pio";
2316				break;
2317			case ATA_PROT_DMA:
2318				prot_str = "dma";
2319				break;
2320			case ATA_PROT_NCQ:
2321				prot_str = "ncq dma";
2322				break;
2323			case ATA_PROT_NCQ_NODATA:
2324				prot_str = "ncq nodata";
2325				break;
2326			case ATAPI_PROT_NODATA:
2327				prot_str = "nodata";
2328				break;
2329			case ATAPI_PROT_PIO:
2330				prot_str = "pio";
2331				break;
2332			case ATAPI_PROT_DMA:
2333				prot_str = "dma";
2334				break;
2335			}
2336			snprintf(data_buf, sizeof(data_buf), " %s %u %s",
2337				 prot_str, qc->nbytes, dma_str[qc->dma_dir]);
2338		}
2339
2340		if (ata_is_atapi(qc->tf.protocol)) {
2341			const u8 *cdb = qc->cdb;
2342			size_t cdb_len = qc->dev->cdb_len;
2343
2344			if (qc->scsicmd) {
2345				cdb = qc->scsicmd->cmnd;
2346				cdb_len = qc->scsicmd->cmd_len;
2347			}
2348			__scsi_format_command(cdb_buf, sizeof(cdb_buf),
2349					      cdb, cdb_len);
2350		} else {
2351			const char *descr = ata_get_cmd_descript(cmd->command);
2352			if (descr)
2353				ata_dev_err(qc->dev, "failed command: %s\n",
2354					    descr);
2355		}
2356
2357		ata_dev_err(qc->dev,
2358			"cmd %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2359			"tag %d%s\n         %s"
2360			"res %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2361			"Emask 0x%x (%s)%s\n",
2362			cmd->command, cmd->feature, cmd->nsect,
2363			cmd->lbal, cmd->lbam, cmd->lbah,
2364			cmd->hob_feature, cmd->hob_nsect,
2365			cmd->hob_lbal, cmd->hob_lbam, cmd->hob_lbah,
2366			cmd->device, qc->tag, data_buf, cdb_buf,
2367			res->command, res->feature, res->nsect,
2368			res->lbal, res->lbam, res->lbah,
2369			res->hob_feature, res->hob_nsect,
2370			res->hob_lbal, res->hob_lbam, res->hob_lbah,
2371			res->device, qc->err_mask, ata_err_string(qc->err_mask),
2372			qc->err_mask & AC_ERR_NCQ ? " <F>" : "");
2373
2374#ifdef CONFIG_ATA_VERBOSE_ERROR
2375		if (res->command & (ATA_BUSY | ATA_DRDY | ATA_DF | ATA_DRQ |
2376				    ATA_SENSE | ATA_ERR)) {
2377			if (res->command & ATA_BUSY)
2378				ata_dev_err(qc->dev, "status: { Busy }\n");
2379			else
2380				ata_dev_err(qc->dev, "status: { %s%s%s%s%s}\n",
2381				  res->command & ATA_DRDY ? "DRDY " : "",
2382				  res->command & ATA_DF ? "DF " : "",
2383				  res->command & ATA_DRQ ? "DRQ " : "",
2384				  res->command & ATA_SENSE ? "SENSE " : "",
2385				  res->command & ATA_ERR ? "ERR " : "");
2386		}
2387
2388		if (cmd->command != ATA_CMD_PACKET &&
2389		    (res->feature & (ATA_ICRC | ATA_UNC | ATA_AMNF |
2390				     ATA_IDNF | ATA_ABORTED)))
2391			ata_dev_err(qc->dev, "error: { %s%s%s%s%s}\n",
2392			  res->feature & ATA_ICRC ? "ICRC " : "",
2393			  res->feature & ATA_UNC ? "UNC " : "",
2394			  res->feature & ATA_AMNF ? "AMNF " : "",
2395			  res->feature & ATA_IDNF ? "IDNF " : "",
2396			  res->feature & ATA_ABORTED ? "ABRT " : "");
2397#endif
2398	}
2399}
2400
2401/**
2402 *	ata_eh_report - report error handling to user
2403 *	@ap: ATA port to report EH about
2404 *
2405 *	Report EH to user.
2406 *
2407 *	LOCKING:
2408 *	None.
2409 */
2410void ata_eh_report(struct ata_port *ap)
2411{
2412	struct ata_link *link;
2413
2414	ata_for_each_link(link, ap, HOST_FIRST)
2415		ata_eh_link_report(link);
2416}
2417
2418static int ata_do_reset(struct ata_link *link, ata_reset_fn_t reset,
2419			unsigned int *classes, unsigned long deadline,
2420			bool clear_classes)
2421{
2422	struct ata_device *dev;
2423
2424	if (clear_classes)
2425		ata_for_each_dev(dev, link, ALL)
2426			classes[dev->devno] = ATA_DEV_UNKNOWN;
2427
2428	return reset(link, classes, deadline);
2429}
2430
2431static int ata_eh_followup_srst_needed(struct ata_link *link, int rc)
2432{
2433	if ((link->flags & ATA_LFLAG_NO_SRST) || ata_link_offline(link))
2434		return 0;
2435	if (rc == -EAGAIN)
2436		return 1;
2437	if (sata_pmp_supported(link->ap) && ata_is_host_link(link))
2438		return 1;
2439	return 0;
2440}
2441
2442int ata_eh_reset(struct ata_link *link, int classify,
2443		 ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
2444		 ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
2445{
2446	struct ata_port *ap = link->ap;
2447	struct ata_link *slave = ap->slave_link;
2448	struct ata_eh_context *ehc = &link->eh_context;
2449	struct ata_eh_context *sehc = slave ? &slave->eh_context : NULL;
2450	unsigned int *classes = ehc->classes;
2451	unsigned int lflags = link->flags;
2452	int verbose = !(ehc->i.flags & ATA_EHI_QUIET);
2453	int max_tries = 0, try = 0;
2454	struct ata_link *failed_link;
2455	struct ata_device *dev;
2456	unsigned long deadline, now;
2457	ata_reset_fn_t reset;
2458	unsigned long flags;
2459	u32 sstatus;
2460	int nr_unknown, rc;
2461
2462	/*
2463	 * Prepare to reset
2464	 */
2465	while (ata_eh_reset_timeouts[max_tries] != ULONG_MAX)
2466		max_tries++;
2467	if (link->flags & ATA_LFLAG_RST_ONCE)
2468		max_tries = 1;
2469	if (link->flags & ATA_LFLAG_NO_HRST)
2470		hardreset = NULL;
2471	if (link->flags & ATA_LFLAG_NO_SRST)
2472		softreset = NULL;
2473
2474	/* make sure each reset attempt is at least COOL_DOWN apart */
2475	if (ehc->i.flags & ATA_EHI_DID_RESET) {
2476		now = jiffies;
2477		WARN_ON(time_after(ehc->last_reset, now));
2478		deadline = ata_deadline(ehc->last_reset,
2479					ATA_EH_RESET_COOL_DOWN);
2480		if (time_before(now, deadline))
2481			schedule_timeout_uninterruptible(deadline - now);
2482	}
2483
2484	spin_lock_irqsave(ap->lock, flags);
2485	ap->pflags |= ATA_PFLAG_RESETTING;
2486	spin_unlock_irqrestore(ap->lock, flags);
2487
2488	ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2489
2490	ata_for_each_dev(dev, link, ALL) {
2491		/* If we issue an SRST then an ATA drive (not ATAPI)
2492		 * may change configuration and be in PIO0 timing. If
2493		 * we do a hard reset (or are coming from power on)
2494		 * this is true for ATA or ATAPI. Until we've set a
2495		 * suitable controller mode we should not touch the
2496		 * bus as we may be talking too fast.
2497		 */
2498		dev->pio_mode = XFER_PIO_0;
2499		dev->dma_mode = 0xff;
2500
2501		/* If the controller has a pio mode setup function
2502		 * then use it to set the chipset to rights. Don't
2503		 * touch the DMA setup as that will be dealt with when
2504		 * configuring devices.
2505		 */
2506		if (ap->ops->set_piomode)
2507			ap->ops->set_piomode(ap, dev);
2508	}
2509
2510	/* prefer hardreset */
2511	reset = NULL;
2512	ehc->i.action &= ~ATA_EH_RESET;
2513	if (hardreset) {
2514		reset = hardreset;
2515		ehc->i.action |= ATA_EH_HARDRESET;
2516	} else if (softreset) {
2517		reset = softreset;
2518		ehc->i.action |= ATA_EH_SOFTRESET;
2519	}
2520
2521	if (prereset) {
2522		unsigned long deadline = ata_deadline(jiffies,
2523						      ATA_EH_PRERESET_TIMEOUT);
2524
2525		if (slave) {
2526			sehc->i.action &= ~ATA_EH_RESET;
2527			sehc->i.action |= ehc->i.action;
2528		}
2529
2530		rc = prereset(link, deadline);
2531
2532		/* If present, do prereset on slave link too.  Reset
2533		 * is skipped iff both master and slave links report
2534		 * -ENOENT or clear ATA_EH_RESET.
2535		 */
2536		if (slave && (rc == 0 || rc == -ENOENT)) {
2537			int tmp;
2538
2539			tmp = prereset(slave, deadline);
2540			if (tmp != -ENOENT)
2541				rc = tmp;
2542
2543			ehc->i.action |= sehc->i.action;
2544		}
2545
2546		if (rc) {
2547			if (rc == -ENOENT) {
2548				ata_link_dbg(link, "port disabled--ignoring\n");
2549				ehc->i.action &= ~ATA_EH_RESET;
2550
2551				ata_for_each_dev(dev, link, ALL)
2552					classes[dev->devno] = ATA_DEV_NONE;
2553
2554				rc = 0;
2555			} else
2556				ata_link_err(link,
2557					     "prereset failed (errno=%d)\n",
2558					     rc);
2559			goto out;
2560		}
2561
2562		/* prereset() might have cleared ATA_EH_RESET.  If so,
2563		 * bang classes, thaw and return.
2564		 */
2565		if (reset && !(ehc->i.action & ATA_EH_RESET)) {
2566			ata_for_each_dev(dev, link, ALL)
2567				classes[dev->devno] = ATA_DEV_NONE;
2568			if ((ap->pflags & ATA_PFLAG_FROZEN) &&
2569			    ata_is_host_link(link))
2570				ata_eh_thaw_port(ap);
2571			rc = 0;
2572			goto out;
2573		}
2574	}
2575
2576 retry:
2577	/*
2578	 * Perform reset
2579	 */
2580	if (ata_is_host_link(link))
2581		ata_eh_freeze_port(ap);
2582
2583	deadline = ata_deadline(jiffies, ata_eh_reset_timeouts[try++]);
2584
2585	if (reset) {
2586		if (verbose)
2587			ata_link_info(link, "%s resetting link\n",
2588				      reset == softreset ? "soft" : "hard");
2589
2590		/* mark that this EH session started with reset */
2591		ehc->last_reset = jiffies;
2592		if (reset == hardreset)
2593			ehc->i.flags |= ATA_EHI_DID_HARDRESET;
2594		else
2595			ehc->i.flags |= ATA_EHI_DID_SOFTRESET;
2596
2597		rc = ata_do_reset(link, reset, classes, deadline, true);
2598		if (rc && rc != -EAGAIN) {
2599			failed_link = link;
2600			goto fail;
2601		}
2602
2603		/* hardreset slave link if existent */
2604		if (slave && reset == hardreset) {
2605			int tmp;
2606
2607			if (verbose)
2608				ata_link_info(slave, "hard resetting link\n");
2609
2610			ata_eh_about_to_do(slave, NULL, ATA_EH_RESET);
2611			tmp = ata_do_reset(slave, reset, classes, deadline,
2612					   false);
2613			switch (tmp) {
2614			case -EAGAIN:
2615				rc = -EAGAIN;
 
2616			case 0:
2617				break;
2618			default:
2619				failed_link = slave;
2620				rc = tmp;
2621				goto fail;
2622			}
2623		}
2624
2625		/* perform follow-up SRST if necessary */
2626		if (reset == hardreset &&
2627		    ata_eh_followup_srst_needed(link, rc)) {
2628			reset = softreset;
2629
2630			if (!reset) {
2631				ata_link_err(link,
2632	     "follow-up softreset required but no softreset available\n");
2633				failed_link = link;
2634				rc = -EINVAL;
2635				goto fail;
2636			}
2637
2638			ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2639			rc = ata_do_reset(link, reset, classes, deadline, true);
2640			if (rc) {
2641				failed_link = link;
2642				goto fail;
2643			}
2644		}
2645	} else {
2646		if (verbose)
2647			ata_link_info(link,
2648	"no reset method available, skipping reset\n");
2649		if (!(lflags & ATA_LFLAG_ASSUME_CLASS))
2650			lflags |= ATA_LFLAG_ASSUME_ATA;
2651	}
2652
2653	/*
2654	 * Post-reset processing
2655	 */
2656	ata_for_each_dev(dev, link, ALL) {
2657		/* After the reset, the device state is PIO 0 and the
2658		 * controller state is undefined.  Reset also wakes up
2659		 * drives from sleeping mode.
2660		 */
2661		dev->pio_mode = XFER_PIO_0;
2662		dev->flags &= ~ATA_DFLAG_SLEEPING;
2663
2664		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
2665			continue;
2666
2667		/* apply class override */
2668		if (lflags & ATA_LFLAG_ASSUME_ATA)
2669			classes[dev->devno] = ATA_DEV_ATA;
2670		else if (lflags & ATA_LFLAG_ASSUME_SEMB)
2671			classes[dev->devno] = ATA_DEV_SEMB_UNSUP;
2672	}
2673
2674	/* record current link speed */
2675	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0)
2676		link->sata_spd = (sstatus >> 4) & 0xf;
2677	if (slave && sata_scr_read(slave, SCR_STATUS, &sstatus) == 0)
2678		slave->sata_spd = (sstatus >> 4) & 0xf;
2679
2680	/* thaw the port */
2681	if (ata_is_host_link(link))
2682		ata_eh_thaw_port(ap);
2683
2684	/* postreset() should clear hardware SError.  Although SError
2685	 * is cleared during link resume, clearing SError here is
2686	 * necessary as some PHYs raise hotplug events after SRST.
2687	 * This introduces race condition where hotplug occurs between
2688	 * reset and here.  This race is mediated by cross checking
2689	 * link onlineness and classification result later.
2690	 */
2691	if (postreset) {
2692		postreset(link, classes);
2693		if (slave)
2694			postreset(slave, classes);
2695	}
2696
2697	/*
2698	 * Some controllers can't be frozen very well and may set spurious
2699	 * error conditions during reset.  Clear accumulated error
2700	 * information and re-thaw the port if frozen.  As reset is the
2701	 * final recovery action and we cross check link onlineness against
2702	 * device classification later, no hotplug event is lost by this.
2703	 */
2704	spin_lock_irqsave(link->ap->lock, flags);
2705	memset(&link->eh_info, 0, sizeof(link->eh_info));
2706	if (slave)
2707		memset(&slave->eh_info, 0, sizeof(link->eh_info));
2708	ap->pflags &= ~ATA_PFLAG_EH_PENDING;
2709	spin_unlock_irqrestore(link->ap->lock, flags);
2710
2711	if (ap->pflags & ATA_PFLAG_FROZEN)
2712		ata_eh_thaw_port(ap);
2713
2714	/*
2715	 * Make sure onlineness and classification result correspond.
2716	 * Hotplug could have happened during reset and some
2717	 * controllers fail to wait while a drive is spinning up after
2718	 * being hotplugged causing misdetection.  By cross checking
2719	 * link on/offlineness and classification result, those
2720	 * conditions can be reliably detected and retried.
2721	 */
2722	nr_unknown = 0;
2723	ata_for_each_dev(dev, link, ALL) {
2724		if (ata_phys_link_online(ata_dev_phys_link(dev))) {
2725			if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2726				ata_dev_dbg(dev, "link online but device misclassified\n");
2727				classes[dev->devno] = ATA_DEV_NONE;
2728				nr_unknown++;
2729			}
2730		} else if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
2731			if (ata_class_enabled(classes[dev->devno]))
2732				ata_dev_dbg(dev,
2733					    "link offline, clearing class %d to NONE\n",
2734					    classes[dev->devno]);
2735			classes[dev->devno] = ATA_DEV_NONE;
2736		} else if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2737			ata_dev_dbg(dev,
2738				    "link status unknown, clearing UNKNOWN to NONE\n");
2739			classes[dev->devno] = ATA_DEV_NONE;
2740		}
2741	}
2742
2743	if (classify && nr_unknown) {
2744		if (try < max_tries) {
2745			ata_link_warn(link,
2746				      "link online but %d devices misclassified, retrying\n",
2747				      nr_unknown);
2748			failed_link = link;
2749			rc = -EAGAIN;
2750			goto fail;
2751		}
2752		ata_link_warn(link,
2753			      "link online but %d devices misclassified, "
2754			      "device detection might fail\n", nr_unknown);
2755	}
2756
2757	/* reset successful, schedule revalidation */
2758	ata_eh_done(link, NULL, ATA_EH_RESET);
2759	if (slave)
2760		ata_eh_done(slave, NULL, ATA_EH_RESET);
2761	ehc->last_reset = jiffies;		/* update to completion time */
2762	ehc->i.action |= ATA_EH_REVALIDATE;
2763	link->lpm_policy = ATA_LPM_UNKNOWN;	/* reset LPM state */
2764
2765	rc = 0;
2766 out:
2767	/* clear hotplug flag */
2768	ehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2769	if (slave)
2770		sehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2771
2772	spin_lock_irqsave(ap->lock, flags);
2773	ap->pflags &= ~ATA_PFLAG_RESETTING;
2774	spin_unlock_irqrestore(ap->lock, flags);
2775
2776	return rc;
2777
2778 fail:
2779	/* if SCR isn't accessible on a fan-out port, PMP needs to be reset */
2780	if (!ata_is_host_link(link) &&
2781	    sata_scr_read(link, SCR_STATUS, &sstatus))
2782		rc = -ERESTART;
2783
2784	if (try >= max_tries) {
2785		/*
2786		 * Thaw host port even if reset failed, so that the port
2787		 * can be retried on the next phy event.  This risks
2788		 * repeated EH runs but seems to be a better tradeoff than
2789		 * shutting down a port after a botched hotplug attempt.
2790		 */
2791		if (ata_is_host_link(link))
2792			ata_eh_thaw_port(ap);
2793		goto out;
2794	}
2795
2796	now = jiffies;
2797	if (time_before(now, deadline)) {
2798		unsigned long delta = deadline - now;
2799
2800		ata_link_warn(failed_link,
2801			"reset failed (errno=%d), retrying in %u secs\n",
2802			rc, DIV_ROUND_UP(jiffies_to_msecs(delta), 1000));
2803
2804		ata_eh_release(ap);
2805		while (delta)
2806			delta = schedule_timeout_uninterruptible(delta);
2807		ata_eh_acquire(ap);
2808	}
2809
2810	/*
2811	 * While disks spinup behind PMP, some controllers fail sending SRST.
2812	 * They need to be reset - as well as the PMP - before retrying.
2813	 */
2814	if (rc == -ERESTART) {
2815		if (ata_is_host_link(link))
2816			ata_eh_thaw_port(ap);
2817		goto out;
2818	}
2819
2820	if (try == max_tries - 1) {
2821		sata_down_spd_limit(link, 0);
2822		if (slave)
2823			sata_down_spd_limit(slave, 0);
2824	} else if (rc == -EPIPE)
2825		sata_down_spd_limit(failed_link, 0);
2826
2827	if (hardreset)
2828		reset = hardreset;
2829	goto retry;
2830}
2831
2832static inline void ata_eh_pull_park_action(struct ata_port *ap)
2833{
2834	struct ata_link *link;
2835	struct ata_device *dev;
2836	unsigned long flags;
2837
2838	/*
2839	 * This function can be thought of as an extended version of
2840	 * ata_eh_about_to_do() specially crafted to accommodate the
2841	 * requirements of ATA_EH_PARK handling. Since the EH thread
2842	 * does not leave the do {} while () loop in ata_eh_recover as
2843	 * long as the timeout for a park request to *one* device on
2844	 * the port has not expired, and since we still want to pick
2845	 * up park requests to other devices on the same port or
2846	 * timeout updates for the same device, we have to pull
2847	 * ATA_EH_PARK actions from eh_info into eh_context.i
2848	 * ourselves at the beginning of each pass over the loop.
2849	 *
2850	 * Additionally, all write accesses to &ap->park_req_pending
2851	 * through reinit_completion() (see below) or complete_all()
2852	 * (see ata_scsi_park_store()) are protected by the host lock.
2853	 * As a result we have that park_req_pending.done is zero on
2854	 * exit from this function, i.e. when ATA_EH_PARK actions for
2855	 * *all* devices on port ap have been pulled into the
2856	 * respective eh_context structs. If, and only if,
2857	 * park_req_pending.done is non-zero by the time we reach
2858	 * wait_for_completion_timeout(), another ATA_EH_PARK action
2859	 * has been scheduled for at least one of the devices on port
2860	 * ap and we have to cycle over the do {} while () loop in
2861	 * ata_eh_recover() again.
2862	 */
2863
2864	spin_lock_irqsave(ap->lock, flags);
2865	reinit_completion(&ap->park_req_pending);
2866	ata_for_each_link(link, ap, EDGE) {
2867		ata_for_each_dev(dev, link, ALL) {
2868			struct ata_eh_info *ehi = &link->eh_info;
2869
2870			link->eh_context.i.dev_action[dev->devno] |=
2871				ehi->dev_action[dev->devno] & ATA_EH_PARK;
2872			ata_eh_clear_action(link, dev, ehi, ATA_EH_PARK);
2873		}
2874	}
2875	spin_unlock_irqrestore(ap->lock, flags);
2876}
2877
2878static void ata_eh_park_issue_cmd(struct ata_device *dev, int park)
2879{
2880	struct ata_eh_context *ehc = &dev->link->eh_context;
2881	struct ata_taskfile tf;
2882	unsigned int err_mask;
2883
2884	ata_tf_init(dev, &tf);
2885	if (park) {
2886		ehc->unloaded_mask |= 1 << dev->devno;
2887		tf.command = ATA_CMD_IDLEIMMEDIATE;
2888		tf.feature = 0x44;
2889		tf.lbal = 0x4c;
2890		tf.lbam = 0x4e;
2891		tf.lbah = 0x55;
2892	} else {
2893		ehc->unloaded_mask &= ~(1 << dev->devno);
2894		tf.command = ATA_CMD_CHK_POWER;
2895	}
2896
2897	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
2898	tf.protocol = ATA_PROT_NODATA;
2899	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
2900	if (park && (err_mask || tf.lbal != 0xc4)) {
2901		ata_dev_err(dev, "head unload failed!\n");
2902		ehc->unloaded_mask &= ~(1 << dev->devno);
2903	}
2904}
2905
2906static int ata_eh_revalidate_and_attach(struct ata_link *link,
2907					struct ata_device **r_failed_dev)
2908{
2909	struct ata_port *ap = link->ap;
2910	struct ata_eh_context *ehc = &link->eh_context;
2911	struct ata_device *dev;
2912	unsigned int new_mask = 0;
2913	unsigned long flags;
2914	int rc = 0;
2915
2916	DPRINTK("ENTER\n");
2917
2918	/* For PATA drive side cable detection to work, IDENTIFY must
2919	 * be done backwards such that PDIAG- is released by the slave
2920	 * device before the master device is identified.
2921	 */
2922	ata_for_each_dev(dev, link, ALL_REVERSE) {
2923		unsigned int action = ata_eh_dev_action(dev);
2924		unsigned int readid_flags = 0;
2925
2926		if (ehc->i.flags & ATA_EHI_DID_RESET)
2927			readid_flags |= ATA_READID_POSTRESET;
2928
2929		if ((action & ATA_EH_REVALIDATE) && ata_dev_enabled(dev)) {
2930			WARN_ON(dev->class == ATA_DEV_PMP);
2931
2932			if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
2933				rc = -EIO;
2934				goto err;
2935			}
2936
2937			ata_eh_about_to_do(link, dev, ATA_EH_REVALIDATE);
2938			rc = ata_dev_revalidate(dev, ehc->classes[dev->devno],
2939						readid_flags);
2940			if (rc)
2941				goto err;
2942
2943			ata_eh_done(link, dev, ATA_EH_REVALIDATE);
2944
2945			/* Configuration may have changed, reconfigure
2946			 * transfer mode.
2947			 */
2948			ehc->i.flags |= ATA_EHI_SETMODE;
2949
2950			/* schedule the scsi_rescan_device() here */
2951			schedule_work(&(ap->scsi_rescan_task));
2952		} else if (dev->class == ATA_DEV_UNKNOWN &&
2953			   ehc->tries[dev->devno] &&
2954			   ata_class_enabled(ehc->classes[dev->devno])) {
2955			/* Temporarily set dev->class, it will be
2956			 * permanently set once all configurations are
2957			 * complete.  This is necessary because new
2958			 * device configuration is done in two
2959			 * separate loops.
2960			 */
2961			dev->class = ehc->classes[dev->devno];
2962
2963			if (dev->class == ATA_DEV_PMP)
2964				rc = sata_pmp_attach(dev);
2965			else
2966				rc = ata_dev_read_id(dev, &dev->class,
2967						     readid_flags, dev->id);
2968
2969			/* read_id might have changed class, store and reset */
2970			ehc->classes[dev->devno] = dev->class;
2971			dev->class = ATA_DEV_UNKNOWN;
2972
2973			switch (rc) {
2974			case 0:
2975				/* clear error info accumulated during probe */
2976				ata_ering_clear(&dev->ering);
2977				new_mask |= 1 << dev->devno;
2978				break;
2979			case -ENOENT:
2980				/* IDENTIFY was issued to non-existent
2981				 * device.  No need to reset.  Just
2982				 * thaw and ignore the device.
2983				 */
2984				ata_eh_thaw_port(ap);
2985				break;
2986			default:
2987				goto err;
2988			}
2989		}
2990	}
2991
2992	/* PDIAG- should have been released, ask cable type if post-reset */
2993	if ((ehc->i.flags & ATA_EHI_DID_RESET) && ata_is_host_link(link)) {
2994		if (ap->ops->cable_detect)
2995			ap->cbl = ap->ops->cable_detect(ap);
2996		ata_force_cbl(ap);
2997	}
2998
2999	/* Configure new devices forward such that user doesn't see
3000	 * device detection messages backwards.
3001	 */
3002	ata_for_each_dev(dev, link, ALL) {
3003		if (!(new_mask & (1 << dev->devno)))
3004			continue;
3005
3006		dev->class = ehc->classes[dev->devno];
3007
3008		if (dev->class == ATA_DEV_PMP)
3009			continue;
3010
3011		ehc->i.flags |= ATA_EHI_PRINTINFO;
3012		rc = ata_dev_configure(dev);
3013		ehc->i.flags &= ~ATA_EHI_PRINTINFO;
3014		if (rc) {
3015			dev->class = ATA_DEV_UNKNOWN;
3016			goto err;
3017		}
3018
3019		spin_lock_irqsave(ap->lock, flags);
3020		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
3021		spin_unlock_irqrestore(ap->lock, flags);
3022
3023		/* new device discovered, configure xfermode */
3024		ehc->i.flags |= ATA_EHI_SETMODE;
3025	}
3026
3027	return 0;
3028
3029 err:
3030	*r_failed_dev = dev;
3031	DPRINTK("EXIT rc=%d\n", rc);
3032	return rc;
3033}
3034
3035/**
3036 *	ata_set_mode - Program timings and issue SET FEATURES - XFER
3037 *	@link: link on which timings will be programmed
3038 *	@r_failed_dev: out parameter for failed device
3039 *
3040 *	Set ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3041 *	ata_set_mode() fails, pointer to the failing device is
3042 *	returned in @r_failed_dev.
3043 *
3044 *	LOCKING:
3045 *	PCI/etc. bus probe sem.
3046 *
3047 *	RETURNS:
3048 *	0 on success, negative errno otherwise
3049 */
3050int ata_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3051{
3052	struct ata_port *ap = link->ap;
3053	struct ata_device *dev;
3054	int rc;
3055
3056	/* if data transfer is verified, clear DUBIOUS_XFER on ering top */
3057	ata_for_each_dev(dev, link, ENABLED) {
3058		if (!(dev->flags & ATA_DFLAG_DUBIOUS_XFER)) {
3059			struct ata_ering_entry *ent;
3060
3061			ent = ata_ering_top(&dev->ering);
3062			if (ent)
3063				ent->eflags &= ~ATA_EFLAG_DUBIOUS_XFER;
3064		}
3065	}
3066
3067	/* has private set_mode? */
3068	if (ap->ops->set_mode)
3069		rc = ap->ops->set_mode(link, r_failed_dev);
3070	else
3071		rc = ata_do_set_mode(link, r_failed_dev);
3072
3073	/* if transfer mode has changed, set DUBIOUS_XFER on device */
3074	ata_for_each_dev(dev, link, ENABLED) {
3075		struct ata_eh_context *ehc = &link->eh_context;
3076		u8 saved_xfer_mode = ehc->saved_xfer_mode[dev->devno];
3077		u8 saved_ncq = !!(ehc->saved_ncq_enabled & (1 << dev->devno));
3078
3079		if (dev->xfer_mode != saved_xfer_mode ||
3080		    ata_ncq_enabled(dev) != saved_ncq)
3081			dev->flags |= ATA_DFLAG_DUBIOUS_XFER;
3082	}
3083
3084	return rc;
3085}
3086
3087/**
3088 *	atapi_eh_clear_ua - Clear ATAPI UNIT ATTENTION after reset
3089 *	@dev: ATAPI device to clear UA for
3090 *
3091 *	Resets and other operations can make an ATAPI device raise
3092 *	UNIT ATTENTION which causes the next operation to fail.  This
3093 *	function clears UA.
3094 *
3095 *	LOCKING:
3096 *	EH context (may sleep).
3097 *
3098 *	RETURNS:
3099 *	0 on success, -errno on failure.
3100 */
3101static int atapi_eh_clear_ua(struct ata_device *dev)
3102{
3103	int i;
3104
3105	for (i = 0; i < ATA_EH_UA_TRIES; i++) {
3106		u8 *sense_buffer = dev->link->ap->sector_buf;
3107		u8 sense_key = 0;
3108		unsigned int err_mask;
3109
3110		err_mask = atapi_eh_tur(dev, &sense_key);
3111		if (err_mask != 0 && err_mask != AC_ERR_DEV) {
3112			ata_dev_warn(dev,
3113				     "TEST_UNIT_READY failed (err_mask=0x%x)\n",
3114				     err_mask);
3115			return -EIO;
3116		}
3117
3118		if (!err_mask || sense_key != UNIT_ATTENTION)
3119			return 0;
3120
3121		err_mask = atapi_eh_request_sense(dev, sense_buffer, sense_key);
3122		if (err_mask) {
3123			ata_dev_warn(dev, "failed to clear "
3124				"UNIT ATTENTION (err_mask=0x%x)\n", err_mask);
3125			return -EIO;
3126		}
3127	}
3128
3129	ata_dev_warn(dev, "UNIT ATTENTION persists after %d tries\n",
3130		     ATA_EH_UA_TRIES);
3131
3132	return 0;
3133}
3134
3135/**
3136 *	ata_eh_maybe_retry_flush - Retry FLUSH if necessary
3137 *	@dev: ATA device which may need FLUSH retry
3138 *
3139 *	If @dev failed FLUSH, it needs to be reported upper layer
3140 *	immediately as it means that @dev failed to remap and already
3141 *	lost at least a sector and further FLUSH retrials won't make
3142 *	any difference to the lost sector.  However, if FLUSH failed
3143 *	for other reasons, for example transmission error, FLUSH needs
3144 *	to be retried.
3145 *
3146 *	This function determines whether FLUSH failure retry is
3147 *	necessary and performs it if so.
3148 *
3149 *	RETURNS:
3150 *	0 if EH can continue, -errno if EH needs to be repeated.
3151 */
3152static int ata_eh_maybe_retry_flush(struct ata_device *dev)
3153{
3154	struct ata_link *link = dev->link;
3155	struct ata_port *ap = link->ap;
3156	struct ata_queued_cmd *qc;
3157	struct ata_taskfile tf;
3158	unsigned int err_mask;
3159	int rc = 0;
3160
3161	/* did flush fail for this device? */
3162	if (!ata_tag_valid(link->active_tag))
3163		return 0;
3164
3165	qc = __ata_qc_from_tag(ap, link->active_tag);
3166	if (qc->dev != dev || (qc->tf.command != ATA_CMD_FLUSH_EXT &&
3167			       qc->tf.command != ATA_CMD_FLUSH))
3168		return 0;
3169
3170	/* if the device failed it, it should be reported to upper layers */
3171	if (qc->err_mask & AC_ERR_DEV)
3172		return 0;
3173
3174	/* flush failed for some other reason, give it another shot */
3175	ata_tf_init(dev, &tf);
3176
3177	tf.command = qc->tf.command;
3178	tf.flags |= ATA_TFLAG_DEVICE;
3179	tf.protocol = ATA_PROT_NODATA;
3180
3181	ata_dev_warn(dev, "retrying FLUSH 0x%x Emask 0x%x\n",
3182		       tf.command, qc->err_mask);
3183
3184	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
3185	if (!err_mask) {
3186		/*
3187		 * FLUSH is complete but there's no way to
3188		 * successfully complete a failed command from EH.
3189		 * Making sure retry is allowed at least once and
3190		 * retrying it should do the trick - whatever was in
3191		 * the cache is already on the platter and this won't
3192		 * cause infinite loop.
3193		 */
3194		qc->scsicmd->allowed = max(qc->scsicmd->allowed, 1);
3195	} else {
3196		ata_dev_warn(dev, "FLUSH failed Emask 0x%x\n",
3197			       err_mask);
3198		rc = -EIO;
3199
3200		/* if device failed it, report it to upper layers */
3201		if (err_mask & AC_ERR_DEV) {
3202			qc->err_mask |= AC_ERR_DEV;
3203			qc->result_tf = tf;
3204			if (!(ap->pflags & ATA_PFLAG_FROZEN))
3205				rc = 0;
3206		}
3207	}
3208	return rc;
3209}
3210
3211/**
3212 *	ata_eh_set_lpm - configure SATA interface power management
3213 *	@link: link to configure power management
3214 *	@policy: the link power management policy
3215 *	@r_failed_dev: out parameter for failed device
3216 *
3217 *	Enable SATA Interface power management.  This will enable
3218 *	Device Interface Power Management (DIPM) for min_power and
3219 *	medium_power_with_dipm policies, and then call driver specific
3220 *	callbacks for enabling Host Initiated Power management.
3221 *
3222 *	LOCKING:
3223 *	EH context.
3224 *
3225 *	RETURNS:
3226 *	0 on success, -errno on failure.
3227 */
3228static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
3229			  struct ata_device **r_failed_dev)
3230{
3231	struct ata_port *ap = ata_is_host_link(link) ? link->ap : NULL;
3232	struct ata_eh_context *ehc = &link->eh_context;
3233	struct ata_device *dev, *link_dev = NULL, *lpm_dev = NULL;
3234	enum ata_lpm_policy old_policy = link->lpm_policy;
3235	bool no_dipm = link->ap->flags & ATA_FLAG_NO_DIPM;
3236	unsigned int hints = ATA_LPM_EMPTY | ATA_LPM_HIPM;
3237	unsigned int err_mask;
3238	int rc;
3239
3240	/* if the link or host doesn't do LPM, noop */
3241	if (!IS_ENABLED(CONFIG_SATA_HOST) ||
3242	    (link->flags & ATA_LFLAG_NO_LPM) || (ap && !ap->ops->set_lpm))
3243		return 0;
3244
3245	/*
3246	 * DIPM is enabled only for MIN_POWER as some devices
3247	 * misbehave when the host NACKs transition to SLUMBER.  Order
3248	 * device and link configurations such that the host always
3249	 * allows DIPM requests.
3250	 */
3251	ata_for_each_dev(dev, link, ENABLED) {
3252		bool hipm = ata_id_has_hipm(dev->id);
3253		bool dipm = ata_id_has_dipm(dev->id) && !no_dipm;
3254
3255		/* find the first enabled and LPM enabled devices */
3256		if (!link_dev)
3257			link_dev = dev;
3258
3259		if (!lpm_dev && (hipm || dipm))
3260			lpm_dev = dev;
3261
3262		hints &= ~ATA_LPM_EMPTY;
3263		if (!hipm)
3264			hints &= ~ATA_LPM_HIPM;
3265
3266		/* disable DIPM before changing link config */
3267		if (policy < ATA_LPM_MED_POWER_WITH_DIPM && dipm) {
3268			err_mask = ata_dev_set_feature(dev,
3269					SETFEATURES_SATA_DISABLE, SATA_DIPM);
3270			if (err_mask && err_mask != AC_ERR_DEV) {
3271				ata_dev_warn(dev,
3272					     "failed to disable DIPM, Emask 0x%x\n",
3273					     err_mask);
3274				rc = -EIO;
3275				goto fail;
3276			}
3277		}
3278	}
3279
3280	if (ap) {
3281		rc = ap->ops->set_lpm(link, policy, hints);
3282		if (!rc && ap->slave_link)
3283			rc = ap->ops->set_lpm(ap->slave_link, policy, hints);
3284	} else
3285		rc = sata_pmp_set_lpm(link, policy, hints);
3286
3287	/*
3288	 * Attribute link config failure to the first (LPM) enabled
3289	 * device on the link.
3290	 */
3291	if (rc) {
3292		if (rc == -EOPNOTSUPP) {
3293			link->flags |= ATA_LFLAG_NO_LPM;
3294			return 0;
3295		}
3296		dev = lpm_dev ? lpm_dev : link_dev;
3297		goto fail;
3298	}
3299
3300	/*
3301	 * Low level driver acked the transition.  Issue DIPM command
3302	 * with the new policy set.
3303	 */
3304	link->lpm_policy = policy;
3305	if (ap && ap->slave_link)
3306		ap->slave_link->lpm_policy = policy;
3307
3308	/* host config updated, enable DIPM if transitioning to MIN_POWER */
3309	ata_for_each_dev(dev, link, ENABLED) {
3310		if (policy >= ATA_LPM_MED_POWER_WITH_DIPM && !no_dipm &&
3311		    ata_id_has_dipm(dev->id)) {
3312			err_mask = ata_dev_set_feature(dev,
3313					SETFEATURES_SATA_ENABLE, SATA_DIPM);
3314			if (err_mask && err_mask != AC_ERR_DEV) {
3315				ata_dev_warn(dev,
3316					"failed to enable DIPM, Emask 0x%x\n",
3317					err_mask);
3318				rc = -EIO;
3319				goto fail;
3320			}
3321		}
3322	}
3323
3324	link->last_lpm_change = jiffies;
3325	link->flags |= ATA_LFLAG_CHANGED;
3326
3327	return 0;
3328
3329fail:
3330	/* restore the old policy */
3331	link->lpm_policy = old_policy;
3332	if (ap && ap->slave_link)
3333		ap->slave_link->lpm_policy = old_policy;
3334
3335	/* if no device or only one more chance is left, disable LPM */
3336	if (!dev || ehc->tries[dev->devno] <= 2) {
3337		ata_link_warn(link, "disabling LPM on the link\n");
3338		link->flags |= ATA_LFLAG_NO_LPM;
3339	}
3340	if (r_failed_dev)
3341		*r_failed_dev = dev;
3342	return rc;
3343}
3344
3345int ata_link_nr_enabled(struct ata_link *link)
3346{
3347	struct ata_device *dev;
3348	int cnt = 0;
3349
3350	ata_for_each_dev(dev, link, ENABLED)
3351		cnt++;
3352	return cnt;
3353}
3354
3355static int ata_link_nr_vacant(struct ata_link *link)
3356{
3357	struct ata_device *dev;
3358	int cnt = 0;
3359
3360	ata_for_each_dev(dev, link, ALL)
3361		if (dev->class == ATA_DEV_UNKNOWN)
3362			cnt++;
3363	return cnt;
3364}
3365
3366static int ata_eh_skip_recovery(struct ata_link *link)
3367{
3368	struct ata_port *ap = link->ap;
3369	struct ata_eh_context *ehc = &link->eh_context;
3370	struct ata_device *dev;
3371
3372	/* skip disabled links */
3373	if (link->flags & ATA_LFLAG_DISABLED)
3374		return 1;
3375
3376	/* skip if explicitly requested */
3377	if (ehc->i.flags & ATA_EHI_NO_RECOVERY)
3378		return 1;
3379
3380	/* thaw frozen port and recover failed devices */
3381	if ((ap->pflags & ATA_PFLAG_FROZEN) || ata_link_nr_enabled(link))
3382		return 0;
3383
3384	/* reset at least once if reset is requested */
3385	if ((ehc->i.action & ATA_EH_RESET) &&
3386	    !(ehc->i.flags & ATA_EHI_DID_RESET))
3387		return 0;
3388
3389	/* skip if class codes for all vacant slots are ATA_DEV_NONE */
3390	ata_for_each_dev(dev, link, ALL) {
3391		if (dev->class == ATA_DEV_UNKNOWN &&
3392		    ehc->classes[dev->devno] != ATA_DEV_NONE)
3393			return 0;
3394	}
3395
3396	return 1;
3397}
3398
3399static int ata_count_probe_trials_cb(struct ata_ering_entry *ent, void *void_arg)
3400{
3401	u64 interval = msecs_to_jiffies(ATA_EH_PROBE_TRIAL_INTERVAL);
3402	u64 now = get_jiffies_64();
3403	int *trials = void_arg;
3404
3405	if ((ent->eflags & ATA_EFLAG_OLD_ER) ||
3406	    (ent->timestamp < now - min(now, interval)))
3407		return -1;
3408
3409	(*trials)++;
3410	return 0;
3411}
3412
3413static int ata_eh_schedule_probe(struct ata_device *dev)
3414{
3415	struct ata_eh_context *ehc = &dev->link->eh_context;
3416	struct ata_link *link = ata_dev_phys_link(dev);
3417	int trials = 0;
3418
3419	if (!(ehc->i.probe_mask & (1 << dev->devno)) ||
3420	    (ehc->did_probe_mask & (1 << dev->devno)))
3421		return 0;
3422
3423	ata_eh_detach_dev(dev);
3424	ata_dev_init(dev);
3425	ehc->did_probe_mask |= (1 << dev->devno);
3426	ehc->i.action |= ATA_EH_RESET;
3427	ehc->saved_xfer_mode[dev->devno] = 0;
3428	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
3429
3430	/* the link maybe in a deep sleep, wake it up */
3431	if (link->lpm_policy > ATA_LPM_MAX_POWER) {
3432		if (ata_is_host_link(link))
3433			link->ap->ops->set_lpm(link, ATA_LPM_MAX_POWER,
3434					       ATA_LPM_EMPTY);
3435		else
3436			sata_pmp_set_lpm(link, ATA_LPM_MAX_POWER,
3437					 ATA_LPM_EMPTY);
3438	}
3439
3440	/* Record and count probe trials on the ering.  The specific
3441	 * error mask used is irrelevant.  Because a successful device
3442	 * detection clears the ering, this count accumulates only if
3443	 * there are consecutive failed probes.
3444	 *
3445	 * If the count is equal to or higher than ATA_EH_PROBE_TRIALS
3446	 * in the last ATA_EH_PROBE_TRIAL_INTERVAL, link speed is
3447	 * forced to 1.5Gbps.
3448	 *
3449	 * This is to work around cases where failed link speed
3450	 * negotiation results in device misdetection leading to
3451	 * infinite DEVXCHG or PHRDY CHG events.
3452	 */
3453	ata_ering_record(&dev->ering, 0, AC_ERR_OTHER);
3454	ata_ering_map(&dev->ering, ata_count_probe_trials_cb, &trials);
3455
3456	if (trials > ATA_EH_PROBE_TRIALS)
3457		sata_down_spd_limit(link, 1);
3458
3459	return 1;
3460}
3461
3462static int ata_eh_handle_dev_fail(struct ata_device *dev, int err)
3463{
3464	struct ata_eh_context *ehc = &dev->link->eh_context;
3465
3466	/* -EAGAIN from EH routine indicates retry without prejudice.
3467	 * The requester is responsible for ensuring forward progress.
3468	 */
3469	if (err != -EAGAIN)
3470		ehc->tries[dev->devno]--;
3471
3472	switch (err) {
3473	case -ENODEV:
3474		/* device missing or wrong IDENTIFY data, schedule probing */
3475		ehc->i.probe_mask |= (1 << dev->devno);
3476		fallthrough;
3477	case -EINVAL:
3478		/* give it just one more chance */
3479		ehc->tries[dev->devno] = min(ehc->tries[dev->devno], 1);
3480		fallthrough;
3481	case -EIO:
3482		if (ehc->tries[dev->devno] == 1) {
3483			/* This is the last chance, better to slow
3484			 * down than lose it.
3485			 */
3486			sata_down_spd_limit(ata_dev_phys_link(dev), 0);
3487			if (dev->pio_mode > XFER_PIO_0)
3488				ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
3489		}
3490	}
3491
3492	if (ata_dev_enabled(dev) && !ehc->tries[dev->devno]) {
3493		/* disable device if it has used up all its chances */
3494		ata_dev_disable(dev);
3495
3496		/* detach if offline */
3497		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
3498			ata_eh_detach_dev(dev);
3499
3500		/* schedule probe if necessary */
3501		if (ata_eh_schedule_probe(dev)) {
3502			ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3503			memset(ehc->cmd_timeout_idx[dev->devno], 0,
3504			       sizeof(ehc->cmd_timeout_idx[dev->devno]));
3505		}
3506
3507		return 1;
3508	} else {
3509		ehc->i.action |= ATA_EH_RESET;
3510		return 0;
3511	}
3512}
3513
3514/**
3515 *	ata_eh_recover - recover host port after error
3516 *	@ap: host port to recover
3517 *	@prereset: prereset method (can be NULL)
3518 *	@softreset: softreset method (can be NULL)
3519 *	@hardreset: hardreset method (can be NULL)
3520 *	@postreset: postreset method (can be NULL)
3521 *	@r_failed_link: out parameter for failed link
3522 *
3523 *	This is the alpha and omega, eum and yang, heart and soul of
3524 *	libata exception handling.  On entry, actions required to
3525 *	recover each link and hotplug requests are recorded in the
3526 *	link's eh_context.  This function executes all the operations
3527 *	with appropriate retrials and fallbacks to resurrect failed
3528 *	devices, detach goners and greet newcomers.
3529 *
3530 *	LOCKING:
3531 *	Kernel thread context (may sleep).
3532 *
3533 *	RETURNS:
3534 *	0 on success, -errno on failure.
3535 */
3536int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
3537		   ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3538		   ata_postreset_fn_t postreset,
3539		   struct ata_link **r_failed_link)
3540{
3541	struct ata_link *link;
3542	struct ata_device *dev;
3543	int rc, nr_fails;
3544	unsigned long flags, deadline;
3545
3546	DPRINTK("ENTER\n");
3547
3548	/* prep for recovery */
3549	ata_for_each_link(link, ap, EDGE) {
3550		struct ata_eh_context *ehc = &link->eh_context;
3551
3552		/* re-enable link? */
3553		if (ehc->i.action & ATA_EH_ENABLE_LINK) {
3554			ata_eh_about_to_do(link, NULL, ATA_EH_ENABLE_LINK);
3555			spin_lock_irqsave(ap->lock, flags);
3556			link->flags &= ~ATA_LFLAG_DISABLED;
3557			spin_unlock_irqrestore(ap->lock, flags);
3558			ata_eh_done(link, NULL, ATA_EH_ENABLE_LINK);
3559		}
3560
3561		ata_for_each_dev(dev, link, ALL) {
3562			if (link->flags & ATA_LFLAG_NO_RETRY)
3563				ehc->tries[dev->devno] = 1;
3564			else
3565				ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3566
3567			/* collect port action mask recorded in dev actions */
3568			ehc->i.action |= ehc->i.dev_action[dev->devno] &
3569					 ~ATA_EH_PERDEV_MASK;
3570			ehc->i.dev_action[dev->devno] &= ATA_EH_PERDEV_MASK;
3571
3572			/* process hotplug request */
3573			if (dev->flags & ATA_DFLAG_DETACH)
3574				ata_eh_detach_dev(dev);
3575
3576			/* schedule probe if necessary */
3577			if (!ata_dev_enabled(dev))
3578				ata_eh_schedule_probe(dev);
3579		}
3580	}
3581
3582 retry:
3583	rc = 0;
3584
3585	/* if UNLOADING, finish immediately */
3586	if (ap->pflags & ATA_PFLAG_UNLOADING)
3587		goto out;
3588
3589	/* prep for EH */
3590	ata_for_each_link(link, ap, EDGE) {
3591		struct ata_eh_context *ehc = &link->eh_context;
3592
3593		/* skip EH if possible. */
3594		if (ata_eh_skip_recovery(link))
3595			ehc->i.action = 0;
3596
3597		ata_for_each_dev(dev, link, ALL)
3598			ehc->classes[dev->devno] = ATA_DEV_UNKNOWN;
3599	}
3600
3601	/* reset */
3602	ata_for_each_link(link, ap, EDGE) {
3603		struct ata_eh_context *ehc = &link->eh_context;
3604
3605		if (!(ehc->i.action & ATA_EH_RESET))
3606			continue;
3607
3608		rc = ata_eh_reset(link, ata_link_nr_vacant(link),
3609				  prereset, softreset, hardreset, postreset);
3610		if (rc) {
3611			ata_link_err(link, "reset failed, giving up\n");
3612			goto out;
3613		}
3614	}
3615
3616	do {
3617		unsigned long now;
3618
3619		/*
3620		 * clears ATA_EH_PARK in eh_info and resets
3621		 * ap->park_req_pending
3622		 */
3623		ata_eh_pull_park_action(ap);
3624
3625		deadline = jiffies;
3626		ata_for_each_link(link, ap, EDGE) {
3627			ata_for_each_dev(dev, link, ALL) {
3628				struct ata_eh_context *ehc = &link->eh_context;
3629				unsigned long tmp;
3630
3631				if (dev->class != ATA_DEV_ATA &&
3632				    dev->class != ATA_DEV_ZAC)
3633					continue;
3634				if (!(ehc->i.dev_action[dev->devno] &
3635				      ATA_EH_PARK))
3636					continue;
3637				tmp = dev->unpark_deadline;
3638				if (time_before(deadline, tmp))
3639					deadline = tmp;
3640				else if (time_before_eq(tmp, jiffies))
3641					continue;
3642				if (ehc->unloaded_mask & (1 << dev->devno))
3643					continue;
3644
3645				ata_eh_park_issue_cmd(dev, 1);
3646			}
3647		}
3648
3649		now = jiffies;
3650		if (time_before_eq(deadline, now))
3651			break;
3652
3653		ata_eh_release(ap);
3654		deadline = wait_for_completion_timeout(&ap->park_req_pending,
3655						       deadline - now);
3656		ata_eh_acquire(ap);
3657	} while (deadline);
3658	ata_for_each_link(link, ap, EDGE) {
3659		ata_for_each_dev(dev, link, ALL) {
3660			if (!(link->eh_context.unloaded_mask &
3661			      (1 << dev->devno)))
3662				continue;
3663
3664			ata_eh_park_issue_cmd(dev, 0);
3665			ata_eh_done(link, dev, ATA_EH_PARK);
3666		}
3667	}
3668
3669	/* the rest */
3670	nr_fails = 0;
3671	ata_for_each_link(link, ap, PMP_FIRST) {
3672		struct ata_eh_context *ehc = &link->eh_context;
3673
3674		if (sata_pmp_attached(ap) && ata_is_host_link(link))
3675			goto config_lpm;
3676
3677		/* revalidate existing devices and attach new ones */
3678		rc = ata_eh_revalidate_and_attach(link, &dev);
3679		if (rc)
3680			goto rest_fail;
3681
3682		/* if PMP got attached, return, pmp EH will take care of it */
3683		if (link->device->class == ATA_DEV_PMP) {
3684			ehc->i.action = 0;
3685			return 0;
3686		}
3687
3688		/* configure transfer mode if necessary */
3689		if (ehc->i.flags & ATA_EHI_SETMODE) {
3690			rc = ata_set_mode(link, &dev);
3691			if (rc)
3692				goto rest_fail;
3693			ehc->i.flags &= ~ATA_EHI_SETMODE;
3694		}
3695
3696		/* If reset has been issued, clear UA to avoid
3697		 * disrupting the current users of the device.
3698		 */
3699		if (ehc->i.flags & ATA_EHI_DID_RESET) {
3700			ata_for_each_dev(dev, link, ALL) {
3701				if (dev->class != ATA_DEV_ATAPI)
3702					continue;
3703				rc = atapi_eh_clear_ua(dev);
3704				if (rc)
3705					goto rest_fail;
3706				if (zpodd_dev_enabled(dev))
3707					zpodd_post_poweron(dev);
3708			}
3709		}
3710
3711		/* retry flush if necessary */
3712		ata_for_each_dev(dev, link, ALL) {
3713			if (dev->class != ATA_DEV_ATA &&
3714			    dev->class != ATA_DEV_ZAC)
3715				continue;
3716			rc = ata_eh_maybe_retry_flush(dev);
3717			if (rc)
3718				goto rest_fail;
3719		}
3720
3721	config_lpm:
3722		/* configure link power saving */
3723		if (link->lpm_policy != ap->target_lpm_policy) {
3724			rc = ata_eh_set_lpm(link, ap->target_lpm_policy, &dev);
3725			if (rc)
3726				goto rest_fail;
3727		}
3728
3729		/* this link is okay now */
3730		ehc->i.flags = 0;
3731		continue;
3732
3733	rest_fail:
3734		nr_fails++;
3735		if (dev)
3736			ata_eh_handle_dev_fail(dev, rc);
3737
3738		if (ap->pflags & ATA_PFLAG_FROZEN) {
3739			/* PMP reset requires working host port.
3740			 * Can't retry if it's frozen.
3741			 */
3742			if (sata_pmp_attached(ap))
3743				goto out;
3744			break;
3745		}
3746	}
3747
3748	if (nr_fails)
3749		goto retry;
3750
3751 out:
3752	if (rc && r_failed_link)
3753		*r_failed_link = link;
3754
3755	DPRINTK("EXIT, rc=%d\n", rc);
3756	return rc;
3757}
3758
3759/**
3760 *	ata_eh_finish - finish up EH
3761 *	@ap: host port to finish EH for
3762 *
3763 *	Recovery is complete.  Clean up EH states and retry or finish
3764 *	failed qcs.
3765 *
3766 *	LOCKING:
3767 *	None.
3768 */
3769void ata_eh_finish(struct ata_port *ap)
3770{
3771	struct ata_queued_cmd *qc;
3772	int tag;
3773
3774	/* retry or finish qcs */
3775	ata_qc_for_each_raw(ap, qc, tag) {
3776		if (!(qc->flags & ATA_QCFLAG_FAILED))
3777			continue;
3778
3779		if (qc->err_mask) {
3780			/* FIXME: Once EH migration is complete,
3781			 * generate sense data in this function,
3782			 * considering both err_mask and tf.
3783			 */
3784			if (qc->flags & ATA_QCFLAG_RETRY)
3785				ata_eh_qc_retry(qc);
3786			else
3787				ata_eh_qc_complete(qc);
3788		} else {
3789			if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
3790				ata_eh_qc_complete(qc);
3791			} else {
3792				/* feed zero TF to sense generation */
3793				memset(&qc->result_tf, 0, sizeof(qc->result_tf));
3794				ata_eh_qc_retry(qc);
3795			}
3796		}
3797	}
3798
3799	/* make sure nr_active_links is zero after EH */
3800	WARN_ON(ap->nr_active_links);
3801	ap->nr_active_links = 0;
3802}
3803
3804/**
3805 *	ata_do_eh - do standard error handling
3806 *	@ap: host port to handle error for
3807 *
3808 *	@prereset: prereset method (can be NULL)
3809 *	@softreset: softreset method (can be NULL)
3810 *	@hardreset: hardreset method (can be NULL)
3811 *	@postreset: postreset method (can be NULL)
3812 *
3813 *	Perform standard error handling sequence.
3814 *
3815 *	LOCKING:
3816 *	Kernel thread context (may sleep).
3817 */
3818void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
3819	       ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3820	       ata_postreset_fn_t postreset)
3821{
3822	struct ata_device *dev;
3823	int rc;
3824
3825	ata_eh_autopsy(ap);
3826	ata_eh_report(ap);
3827
3828	rc = ata_eh_recover(ap, prereset, softreset, hardreset, postreset,
3829			    NULL);
3830	if (rc) {
3831		ata_for_each_dev(dev, &ap->link, ALL)
3832			ata_dev_disable(dev);
3833	}
3834
3835	ata_eh_finish(ap);
3836}
3837
3838/**
3839 *	ata_std_error_handler - standard error handler
3840 *	@ap: host port to handle error for
3841 *
3842 *	Standard error handler
3843 *
3844 *	LOCKING:
3845 *	Kernel thread context (may sleep).
3846 */
3847void ata_std_error_handler(struct ata_port *ap)
3848{
3849	struct ata_port_operations *ops = ap->ops;
3850	ata_reset_fn_t hardreset = ops->hardreset;
3851
3852	/* ignore built-in hardreset if SCR access is not available */
3853	if (hardreset == sata_std_hardreset && !sata_scr_valid(&ap->link))
3854		hardreset = NULL;
3855
3856	ata_do_eh(ap, ops->prereset, ops->softreset, hardreset, ops->postreset);
3857}
3858EXPORT_SYMBOL_GPL(ata_std_error_handler);
3859
3860#ifdef CONFIG_PM
3861/**
3862 *	ata_eh_handle_port_suspend - perform port suspend operation
3863 *	@ap: port to suspend
3864 *
3865 *	Suspend @ap.
3866 *
3867 *	LOCKING:
3868 *	Kernel thread context (may sleep).
3869 */
3870static void ata_eh_handle_port_suspend(struct ata_port *ap)
3871{
3872	unsigned long flags;
3873	int rc = 0;
3874	struct ata_device *dev;
3875
3876	/* are we suspending? */
3877	spin_lock_irqsave(ap->lock, flags);
3878	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
3879	    ap->pm_mesg.event & PM_EVENT_RESUME) {
3880		spin_unlock_irqrestore(ap->lock, flags);
3881		return;
3882	}
3883	spin_unlock_irqrestore(ap->lock, flags);
3884
3885	WARN_ON(ap->pflags & ATA_PFLAG_SUSPENDED);
3886
3887	/*
3888	 * If we have a ZPODD attached, check its zero
3889	 * power ready status before the port is frozen.
3890	 * Only needed for runtime suspend.
3891	 */
3892	if (PMSG_IS_AUTO(ap->pm_mesg)) {
3893		ata_for_each_dev(dev, &ap->link, ENABLED) {
3894			if (zpodd_dev_enabled(dev))
3895				zpodd_on_suspend(dev);
3896		}
3897	}
3898
3899	/* tell ACPI we're suspending */
3900	rc = ata_acpi_on_suspend(ap);
3901	if (rc)
3902		goto out;
3903
3904	/* suspend */
3905	ata_eh_freeze_port(ap);
3906
3907	if (ap->ops->port_suspend)
3908		rc = ap->ops->port_suspend(ap, ap->pm_mesg);
3909
3910	ata_acpi_set_state(ap, ap->pm_mesg);
3911 out:
3912	/* update the flags */
3913	spin_lock_irqsave(ap->lock, flags);
3914
3915	ap->pflags &= ~ATA_PFLAG_PM_PENDING;
3916	if (rc == 0)
3917		ap->pflags |= ATA_PFLAG_SUSPENDED;
3918	else if (ap->pflags & ATA_PFLAG_FROZEN)
3919		ata_port_schedule_eh(ap);
3920
3921	spin_unlock_irqrestore(ap->lock, flags);
3922
3923	return;
3924}
3925
3926/**
3927 *	ata_eh_handle_port_resume - perform port resume operation
3928 *	@ap: port to resume
3929 *
3930 *	Resume @ap.
3931 *
3932 *	LOCKING:
3933 *	Kernel thread context (may sleep).
3934 */
3935static void ata_eh_handle_port_resume(struct ata_port *ap)
3936{
3937	struct ata_link *link;
3938	struct ata_device *dev;
3939	unsigned long flags;
3940
3941	/* are we resuming? */
3942	spin_lock_irqsave(ap->lock, flags);
3943	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
3944	    !(ap->pm_mesg.event & PM_EVENT_RESUME)) {
3945		spin_unlock_irqrestore(ap->lock, flags);
3946		return;
3947	}
3948	spin_unlock_irqrestore(ap->lock, flags);
3949
3950	WARN_ON(!(ap->pflags & ATA_PFLAG_SUSPENDED));
3951
3952	/*
3953	 * Error timestamps are in jiffies which doesn't run while
3954	 * suspended and PHY events during resume isn't too uncommon.
3955	 * When the two are combined, it can lead to unnecessary speed
3956	 * downs if the machine is suspended and resumed repeatedly.
3957	 * Clear error history.
3958	 */
3959	ata_for_each_link(link, ap, HOST_FIRST)
3960		ata_for_each_dev(dev, link, ALL)
3961			ata_ering_clear(&dev->ering);
3962
3963	ata_acpi_set_state(ap, ap->pm_mesg);
3964
3965	if (ap->ops->port_resume)
3966		ap->ops->port_resume(ap);
3967
3968	/* tell ACPI that we're resuming */
3969	ata_acpi_on_resume(ap);
3970
3971	/* update the flags */
3972	spin_lock_irqsave(ap->lock, flags);
3973	ap->pflags &= ~(ATA_PFLAG_PM_PENDING | ATA_PFLAG_SUSPENDED);
3974	spin_unlock_irqrestore(ap->lock, flags);
3975}
3976#endif /* CONFIG_PM */
v5.14.15
   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 long 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	ULONG_MAX,
  94};
  95
  96static const unsigned long ata_eh_flush_timeouts[] = {
  97	15000,	/* be generous with flush */
  98	15000,  /* ditto */
  99	30000,	/* and even more generous */
 100	ULONG_MAX,
 101};
 102
 103static const unsigned long ata_eh_other_timeouts[] = {
 104	 5000,	/* same rationale as identify timeout */
 105	10000,	/* ditto */
 106	/* but no merciful 30sec for other commands, it just isn't worth it */
 107	ULONG_MAX,
 108};
 109
 110struct ata_eh_cmd_timeout_ent {
 111	const u8		*commands;
 112	const unsigned long	*timeouts;
 113};
 114
 115/* The following table determines timeouts to use for EH internal
 116 * commands.  Each table entry is a command class and matches the
 117 * commands the entry applies to and the timeout table to use.
 118 *
 119 * On the retry after a command timed out, the next timeout value from
 120 * the table is used.  If the table doesn't contain further entries,
 121 * the last value is used.
 122 *
 123 * ehc->cmd_timeout_idx keeps track of which timeout to use per
 124 * command class, so if SET_FEATURES times out on the first try, the
 125 * next try will use the second timeout value only for that class.
 126 */
 127#define CMDS(cmds...)	(const u8 []){ cmds, 0 }
 128static const struct ata_eh_cmd_timeout_ent
 129ata_eh_cmd_timeout_table[ATA_EH_CMD_TIMEOUT_TABLE_SIZE] = {
 130	{ .commands = CMDS(ATA_CMD_ID_ATA, ATA_CMD_ID_ATAPI),
 131	  .timeouts = ata_eh_identify_timeouts, },
 132	{ .commands = CMDS(ATA_CMD_READ_NATIVE_MAX, ATA_CMD_READ_NATIVE_MAX_EXT),
 133	  .timeouts = ata_eh_other_timeouts, },
 134	{ .commands = CMDS(ATA_CMD_SET_MAX, ATA_CMD_SET_MAX_EXT),
 135	  .timeouts = ata_eh_other_timeouts, },
 136	{ .commands = CMDS(ATA_CMD_SET_FEATURES),
 137	  .timeouts = ata_eh_other_timeouts, },
 138	{ .commands = CMDS(ATA_CMD_INIT_DEV_PARAMS),
 139	  .timeouts = ata_eh_other_timeouts, },
 140	{ .commands = CMDS(ATA_CMD_FLUSH, ATA_CMD_FLUSH_EXT),
 141	  .timeouts = ata_eh_flush_timeouts },
 142};
 143#undef CMDS
 144
 145static void __ata_port_freeze(struct ata_port *ap);
 146#ifdef CONFIG_PM
 147static void ata_eh_handle_port_suspend(struct ata_port *ap);
 148static void ata_eh_handle_port_resume(struct ata_port *ap);
 149#else /* CONFIG_PM */
 150static void ata_eh_handle_port_suspend(struct ata_port *ap)
 151{ }
 152
 153static void ata_eh_handle_port_resume(struct ata_port *ap)
 154{ }
 155#endif /* CONFIG_PM */
 156
 157static __printf(2, 0) void __ata_ehi_pushv_desc(struct ata_eh_info *ehi,
 158				 const char *fmt, va_list args)
 159{
 160	ehi->desc_len += vscnprintf(ehi->desc + ehi->desc_len,
 161				     ATA_EH_DESC_LEN - ehi->desc_len,
 162				     fmt, args);
 163}
 164
 165/**
 166 *	__ata_ehi_push_desc - push error description without adding separator
 167 *	@ehi: target EHI
 168 *	@fmt: printf format string
 169 *
 170 *	Format string according to @fmt and append it to @ehi->desc.
 171 *
 172 *	LOCKING:
 173 *	spin_lock_irqsave(host lock)
 174 */
 175void __ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 176{
 177	va_list args;
 178
 179	va_start(args, fmt);
 180	__ata_ehi_pushv_desc(ehi, fmt, args);
 181	va_end(args);
 182}
 183EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
 184
 185/**
 186 *	ata_ehi_push_desc - push error description with separator
 187 *	@ehi: target EHI
 188 *	@fmt: printf format string
 189 *
 190 *	Format string according to @fmt and append it to @ehi->desc.
 191 *	If @ehi->desc is not empty, ", " is added in-between.
 192 *
 193 *	LOCKING:
 194 *	spin_lock_irqsave(host lock)
 195 */
 196void ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 197{
 198	va_list args;
 199
 200	if (ehi->desc_len)
 201		__ata_ehi_push_desc(ehi, ", ");
 202
 203	va_start(args, fmt);
 204	__ata_ehi_pushv_desc(ehi, fmt, args);
 205	va_end(args);
 206}
 207EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
 208
 209/**
 210 *	ata_ehi_clear_desc - clean error description
 211 *	@ehi: target EHI
 212 *
 213 *	Clear @ehi->desc.
 214 *
 215 *	LOCKING:
 216 *	spin_lock_irqsave(host lock)
 217 */
 218void ata_ehi_clear_desc(struct ata_eh_info *ehi)
 219{
 220	ehi->desc[0] = '\0';
 221	ehi->desc_len = 0;
 222}
 223EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
 224
 225/**
 226 *	ata_port_desc - append port description
 227 *	@ap: target ATA port
 228 *	@fmt: printf format string
 229 *
 230 *	Format string according to @fmt and append it to port
 231 *	description.  If port description is not empty, " " is added
 232 *	in-between.  This function is to be used while initializing
 233 *	ata_host.  The description is printed on host registration.
 234 *
 235 *	LOCKING:
 236 *	None.
 237 */
 238void ata_port_desc(struct ata_port *ap, const char *fmt, ...)
 239{
 240	va_list args;
 241
 242	WARN_ON(!(ap->pflags & ATA_PFLAG_INITIALIZING));
 243
 244	if (ap->link.eh_info.desc_len)
 245		__ata_ehi_push_desc(&ap->link.eh_info, " ");
 246
 247	va_start(args, fmt);
 248	__ata_ehi_pushv_desc(&ap->link.eh_info, fmt, args);
 249	va_end(args);
 250}
 251EXPORT_SYMBOL_GPL(ata_port_desc);
 252
 253#ifdef CONFIG_PCI
 254/**
 255 *	ata_port_pbar_desc - append PCI BAR description
 256 *	@ap: target ATA port
 257 *	@bar: target PCI BAR
 258 *	@offset: offset into PCI BAR
 259 *	@name: name of the area
 260 *
 261 *	If @offset is negative, this function formats a string which
 262 *	contains the name, address, size and type of the BAR and
 263 *	appends it to the port description.  If @offset is zero or
 264 *	positive, only name and offsetted address is appended.
 265 *
 266 *	LOCKING:
 267 *	None.
 268 */
 269void ata_port_pbar_desc(struct ata_port *ap, int bar, ssize_t offset,
 270			const char *name)
 271{
 272	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 273	char *type = "";
 274	unsigned long long start, len;
 275
 276	if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
 277		type = "m";
 278	else if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
 279		type = "i";
 280
 281	start = (unsigned long long)pci_resource_start(pdev, bar);
 282	len = (unsigned long long)pci_resource_len(pdev, bar);
 283
 284	if (offset < 0)
 285		ata_port_desc(ap, "%s %s%llu@0x%llx", name, type, len, start);
 286	else
 287		ata_port_desc(ap, "%s 0x%llx", name,
 288				start + (unsigned long long)offset);
 289}
 290EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
 291#endif /* CONFIG_PCI */
 292
 293static int ata_lookup_timeout_table(u8 cmd)
 294{
 295	int i;
 296
 297	for (i = 0; i < ATA_EH_CMD_TIMEOUT_TABLE_SIZE; i++) {
 298		const u8 *cur;
 299
 300		for (cur = ata_eh_cmd_timeout_table[i].commands; *cur; cur++)
 301			if (*cur == cmd)
 302				return i;
 303	}
 304
 305	return -1;
 306}
 307
 308/**
 309 *	ata_internal_cmd_timeout - determine timeout for an internal command
 310 *	@dev: target device
 311 *	@cmd: internal command to be issued
 312 *
 313 *	Determine timeout for internal command @cmd for @dev.
 314 *
 315 *	LOCKING:
 316 *	EH context.
 317 *
 318 *	RETURNS:
 319 *	Determined timeout.
 320 */
 321unsigned long ata_internal_cmd_timeout(struct ata_device *dev, u8 cmd)
 322{
 323	struct ata_eh_context *ehc = &dev->link->eh_context;
 324	int ent = ata_lookup_timeout_table(cmd);
 325	int idx;
 326
 327	if (ent < 0)
 328		return ATA_EH_CMD_DFL_TIMEOUT;
 329
 330	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 331	return ata_eh_cmd_timeout_table[ent].timeouts[idx];
 332}
 333
 334/**
 335 *	ata_internal_cmd_timed_out - notification for internal command timeout
 336 *	@dev: target device
 337 *	@cmd: internal command which timed out
 338 *
 339 *	Notify EH that internal command @cmd for @dev timed out.  This
 340 *	function should be called only for commands whose timeouts are
 341 *	determined using ata_internal_cmd_timeout().
 342 *
 343 *	LOCKING:
 344 *	EH context.
 345 */
 346void ata_internal_cmd_timed_out(struct ata_device *dev, u8 cmd)
 347{
 348	struct ata_eh_context *ehc = &dev->link->eh_context;
 349	int ent = ata_lookup_timeout_table(cmd);
 350	int idx;
 351
 352	if (ent < 0)
 353		return;
 354
 355	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 356	if (ata_eh_cmd_timeout_table[ent].timeouts[idx + 1] != ULONG_MAX)
 357		ehc->cmd_timeout_idx[dev->devno][ent]++;
 358}
 359
 360static void ata_ering_record(struct ata_ering *ering, unsigned int eflags,
 361			     unsigned int err_mask)
 362{
 363	struct ata_ering_entry *ent;
 364
 365	WARN_ON(!err_mask);
 366
 367	ering->cursor++;
 368	ering->cursor %= ATA_ERING_SIZE;
 369
 370	ent = &ering->ring[ering->cursor];
 371	ent->eflags = eflags;
 372	ent->err_mask = err_mask;
 373	ent->timestamp = get_jiffies_64();
 374}
 375
 376static struct ata_ering_entry *ata_ering_top(struct ata_ering *ering)
 377{
 378	struct ata_ering_entry *ent = &ering->ring[ering->cursor];
 379
 380	if (ent->err_mask)
 381		return ent;
 382	return NULL;
 383}
 384
 385int ata_ering_map(struct ata_ering *ering,
 386		  int (*map_fn)(struct ata_ering_entry *, void *),
 387		  void *arg)
 388{
 389	int idx, rc = 0;
 390	struct ata_ering_entry *ent;
 391
 392	idx = ering->cursor;
 393	do {
 394		ent = &ering->ring[idx];
 395		if (!ent->err_mask)
 396			break;
 397		rc = map_fn(ent, arg);
 398		if (rc)
 399			break;
 400		idx = (idx - 1 + ATA_ERING_SIZE) % ATA_ERING_SIZE;
 401	} while (idx != ering->cursor);
 402
 403	return rc;
 404}
 405
 406static int ata_ering_clear_cb(struct ata_ering_entry *ent, void *void_arg)
 407{
 408	ent->eflags |= ATA_EFLAG_OLD_ER;
 409	return 0;
 410}
 411
 412static void ata_ering_clear(struct ata_ering *ering)
 413{
 414	ata_ering_map(ering, ata_ering_clear_cb, NULL);
 415}
 416
 417static unsigned int ata_eh_dev_action(struct ata_device *dev)
 418{
 419	struct ata_eh_context *ehc = &dev->link->eh_context;
 420
 421	return ehc->i.action | ehc->i.dev_action[dev->devno];
 422}
 423
 424static void ata_eh_clear_action(struct ata_link *link, struct ata_device *dev,
 425				struct ata_eh_info *ehi, unsigned int action)
 426{
 427	struct ata_device *tdev;
 428
 429	if (!dev) {
 430		ehi->action &= ~action;
 431		ata_for_each_dev(tdev, link, ALL)
 432			ehi->dev_action[tdev->devno] &= ~action;
 433	} else {
 434		/* doesn't make sense for port-wide EH actions */
 435		WARN_ON(!(action & ATA_EH_PERDEV_MASK));
 436
 437		/* break ehi->action into ehi->dev_action */
 438		if (ehi->action & action) {
 439			ata_for_each_dev(tdev, link, ALL)
 440				ehi->dev_action[tdev->devno] |=
 441					ehi->action & action;
 442			ehi->action &= ~action;
 443		}
 444
 445		/* turn off the specified per-dev action */
 446		ehi->dev_action[dev->devno] &= ~action;
 447	}
 448}
 449
 450/**
 451 *	ata_eh_acquire - acquire EH ownership
 452 *	@ap: ATA port to acquire EH ownership for
 453 *
 454 *	Acquire EH ownership for @ap.  This is the basic exclusion
 455 *	mechanism for ports sharing a host.  Only one port hanging off
 456 *	the same host can claim the ownership of EH.
 457 *
 458 *	LOCKING:
 459 *	EH context.
 460 */
 461void ata_eh_acquire(struct ata_port *ap)
 462{
 463	mutex_lock(&ap->host->eh_mutex);
 464	WARN_ON_ONCE(ap->host->eh_owner);
 465	ap->host->eh_owner = current;
 466}
 467
 468/**
 469 *	ata_eh_release - release EH ownership
 470 *	@ap: ATA port to release EH ownership for
 471 *
 472 *	Release EH ownership for @ap if the caller.  The caller must
 473 *	have acquired EH ownership using ata_eh_acquire() previously.
 474 *
 475 *	LOCKING:
 476 *	EH context.
 477 */
 478void ata_eh_release(struct ata_port *ap)
 479{
 480	WARN_ON_ONCE(ap->host->eh_owner != current);
 481	ap->host->eh_owner = NULL;
 482	mutex_unlock(&ap->host->eh_mutex);
 483}
 484
 485static void ata_eh_unload(struct ata_port *ap)
 486{
 487	struct ata_link *link;
 488	struct ata_device *dev;
 489	unsigned long flags;
 490
 491	/* Restore SControl IPM and SPD for the next driver and
 492	 * disable attached devices.
 493	 */
 494	ata_for_each_link(link, ap, PMP_FIRST) {
 495		sata_scr_write(link, SCR_CONTROL, link->saved_scontrol & 0xff0);
 496		ata_for_each_dev(dev, link, ALL)
 497			ata_dev_disable(dev);
 498	}
 499
 500	/* freeze and set UNLOADED */
 501	spin_lock_irqsave(ap->lock, flags);
 502
 503	ata_port_freeze(ap);			/* won't be thawed */
 504	ap->pflags &= ~ATA_PFLAG_EH_PENDING;	/* clear pending from freeze */
 505	ap->pflags |= ATA_PFLAG_UNLOADED;
 506
 507	spin_unlock_irqrestore(ap->lock, flags);
 508}
 509
 510/**
 511 *	ata_scsi_error - SCSI layer error handler callback
 512 *	@host: SCSI host on which error occurred
 513 *
 514 *	Handles SCSI-layer-thrown error events.
 515 *
 516 *	LOCKING:
 517 *	Inherited from SCSI layer (none, can sleep)
 518 *
 519 *	RETURNS:
 520 *	Zero.
 521 */
 522void ata_scsi_error(struct Scsi_Host *host)
 523{
 524	struct ata_port *ap = ata_shost_to_port(host);
 525	unsigned long flags;
 526	LIST_HEAD(eh_work_q);
 527
 528	DPRINTK("ENTER\n");
 529
 530	spin_lock_irqsave(host->host_lock, flags);
 531	list_splice_init(&host->eh_cmd_q, &eh_work_q);
 532	spin_unlock_irqrestore(host->host_lock, flags);
 533
 534	ata_scsi_cmd_error_handler(host, ap, &eh_work_q);
 535
 536	/* If we timed raced normal completion and there is nothing to
 537	   recover nr_timedout == 0 why exactly are we doing error recovery ? */
 538	ata_scsi_port_error_handler(host, ap);
 539
 540	/* finish or retry handled scmd's and clean up */
 541	WARN_ON(!list_empty(&eh_work_q));
 542
 543	DPRINTK("EXIT\n");
 544}
 545
 546/**
 547 * ata_scsi_cmd_error_handler - error callback for a list of commands
 548 * @host:	scsi host containing the port
 549 * @ap:		ATA port within the host
 550 * @eh_work_q:	list of commands to process
 551 *
 552 * process the given list of commands and return those finished to the
 553 * ap->eh_done_q.  This function is the first part of the libata error
 554 * handler which processes a given list of failed commands.
 555 */
 556void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
 557				struct list_head *eh_work_q)
 558{
 559	int i;
 560	unsigned long flags;
 561
 562	/* make sure sff pio task is not running */
 563	ata_sff_flush_pio_task(ap);
 564
 565	/* synchronize with host lock and sort out timeouts */
 566
 567	/* For new EH, all qcs are finished in one of three ways -
 568	 * normal completion, error completion, and SCSI timeout.
 569	 * Both completions can race against SCSI timeout.  When normal
 570	 * completion wins, the qc never reaches EH.  When error
 571	 * completion wins, the qc has ATA_QCFLAG_FAILED set.
 572	 *
 573	 * When SCSI timeout wins, things are a bit more complex.
 574	 * Normal or error completion can occur after the timeout but
 575	 * before this point.  In such cases, both types of
 576	 * completions are honored.  A scmd is determined to have
 577	 * timed out iff its associated qc is active and not failed.
 578	 */
 579	spin_lock_irqsave(ap->lock, flags);
 580	if (ap->ops->error_handler) {
 581		struct scsi_cmnd *scmd, *tmp;
 582		int nr_timedout = 0;
 583
 584		/* This must occur under the ap->lock as we don't want
 585		   a polled recovery to race the real interrupt handler
 586
 587		   The lost_interrupt handler checks for any completed but
 588		   non-notified command and completes much like an IRQ handler.
 589
 590		   We then fall into the error recovery code which will treat
 591		   this as if normal completion won the race */
 592
 593		if (ap->ops->lost_interrupt)
 594			ap->ops->lost_interrupt(ap);
 595
 596		list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
 597			struct ata_queued_cmd *qc;
 598
 599			ata_qc_for_each_raw(ap, qc, i) {
 600				if (qc->flags & ATA_QCFLAG_ACTIVE &&
 601				    qc->scsicmd == scmd)
 602					break;
 603			}
 604
 605			if (i < ATA_MAX_QUEUE) {
 606				/* the scmd has an associated qc */
 607				if (!(qc->flags & ATA_QCFLAG_FAILED)) {
 608					/* which hasn't failed yet, timeout */
 609					qc->err_mask |= AC_ERR_TIMEOUT;
 610					qc->flags |= ATA_QCFLAG_FAILED;
 611					nr_timedout++;
 612				}
 613			} else {
 614				/* Normal completion occurred after
 615				 * SCSI timeout but before this point.
 616				 * Successfully complete it.
 617				 */
 618				scmd->retries = scmd->allowed;
 619				scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
 620			}
 621		}
 622
 623		/* If we have timed out qcs.  They belong to EH from
 624		 * this point but the state of the controller is
 625		 * unknown.  Freeze the port to make sure the IRQ
 626		 * handler doesn't diddle with those qcs.  This must
 627		 * be done atomically w.r.t. setting QCFLAG_FAILED.
 628		 */
 629		if (nr_timedout)
 630			__ata_port_freeze(ap);
 631
 632
 633		/* initialize eh_tries */
 634		ap->eh_tries = ATA_EH_MAX_TRIES;
 635	}
 636	spin_unlock_irqrestore(ap->lock, flags);
 637
 638}
 639EXPORT_SYMBOL(ata_scsi_cmd_error_handler);
 640
 641/**
 642 * ata_scsi_port_error_handler - recover the port after the commands
 643 * @host:	SCSI host containing the port
 644 * @ap:		the ATA port
 645 *
 646 * Handle the recovery of the port @ap after all the commands
 647 * have been recovered.
 648 */
 649void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap)
 650{
 651	unsigned long flags;
 652
 653	/* invoke error handler */
 654	if (ap->ops->error_handler) {
 655		struct ata_link *link;
 656
 657		/* acquire EH ownership */
 658		ata_eh_acquire(ap);
 659 repeat:
 660		/* kill fast drain timer */
 661		del_timer_sync(&ap->fastdrain_timer);
 662
 663		/* process port resume request */
 664		ata_eh_handle_port_resume(ap);
 665
 666		/* fetch & clear EH info */
 667		spin_lock_irqsave(ap->lock, flags);
 668
 669		ata_for_each_link(link, ap, HOST_FIRST) {
 670			struct ata_eh_context *ehc = &link->eh_context;
 671			struct ata_device *dev;
 672
 673			memset(&link->eh_context, 0, sizeof(link->eh_context));
 674			link->eh_context.i = link->eh_info;
 675			memset(&link->eh_info, 0, sizeof(link->eh_info));
 676
 677			ata_for_each_dev(dev, link, ENABLED) {
 678				int devno = dev->devno;
 679
 680				ehc->saved_xfer_mode[devno] = dev->xfer_mode;
 681				if (ata_ncq_enabled(dev))
 682					ehc->saved_ncq_enabled |= 1 << devno;
 683			}
 684		}
 685
 686		ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
 687		ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 688		ap->excl_link = NULL;	/* don't maintain exclusion over EH */
 689
 690		spin_unlock_irqrestore(ap->lock, flags);
 691
 692		/* invoke EH, skip if unloading or suspended */
 693		if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))
 694			ap->ops->error_handler(ap);
 695		else {
 696			/* if unloading, commence suicide */
 697			if ((ap->pflags & ATA_PFLAG_UNLOADING) &&
 698			    !(ap->pflags & ATA_PFLAG_UNLOADED))
 699				ata_eh_unload(ap);
 700			ata_eh_finish(ap);
 701		}
 702
 703		/* process port suspend request */
 704		ata_eh_handle_port_suspend(ap);
 705
 706		/* Exception might have happened after ->error_handler
 707		 * recovered the port but before this point.  Repeat
 708		 * EH in such case.
 709		 */
 710		spin_lock_irqsave(ap->lock, flags);
 711
 712		if (ap->pflags & ATA_PFLAG_EH_PENDING) {
 713			if (--ap->eh_tries) {
 714				spin_unlock_irqrestore(ap->lock, flags);
 715				goto repeat;
 716			}
 717			ata_port_err(ap,
 718				     "EH pending after %d tries, giving up\n",
 719				     ATA_EH_MAX_TRIES);
 720			ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 721		}
 722
 723		/* this run is complete, make sure EH info is clear */
 724		ata_for_each_link(link, ap, HOST_FIRST)
 725			memset(&link->eh_info, 0, sizeof(link->eh_info));
 726
 727		/* end eh (clear host_eh_scheduled) while holding
 728		 * ap->lock such that if exception occurs after this
 729		 * point but before EH completion, SCSI midlayer will
 730		 * re-initiate EH.
 731		 */
 732		ap->ops->end_eh(ap);
 733
 734		spin_unlock_irqrestore(ap->lock, flags);
 735		ata_eh_release(ap);
 736	} else {
 737		WARN_ON(ata_qc_from_tag(ap, ap->link.active_tag) == NULL);
 738		ap->ops->eng_timeout(ap);
 739	}
 740
 741	scsi_eh_flush_done_q(&ap->eh_done_q);
 742
 743	/* clean up */
 744	spin_lock_irqsave(ap->lock, flags);
 745
 746	if (ap->pflags & ATA_PFLAG_LOADING)
 747		ap->pflags &= ~ATA_PFLAG_LOADING;
 748	else if ((ap->pflags & ATA_PFLAG_SCSI_HOTPLUG) &&
 749		!(ap->flags & ATA_FLAG_SAS_HOST))
 750		schedule_delayed_work(&ap->hotplug_task, 0);
 751
 752	if (ap->pflags & ATA_PFLAG_RECOVERED)
 753		ata_port_info(ap, "EH complete\n");
 754
 755	ap->pflags &= ~(ATA_PFLAG_SCSI_HOTPLUG | ATA_PFLAG_RECOVERED);
 756
 757	/* tell wait_eh that we're done */
 758	ap->pflags &= ~ATA_PFLAG_EH_IN_PROGRESS;
 759	wake_up_all(&ap->eh_wait_q);
 760
 761	spin_unlock_irqrestore(ap->lock, flags);
 762}
 763EXPORT_SYMBOL_GPL(ata_scsi_port_error_handler);
 764
 765/**
 766 *	ata_port_wait_eh - Wait for the currently pending EH to complete
 767 *	@ap: Port to wait EH for
 768 *
 769 *	Wait until the currently pending EH is complete.
 770 *
 771 *	LOCKING:
 772 *	Kernel thread context (may sleep).
 773 */
 774void ata_port_wait_eh(struct ata_port *ap)
 775{
 776	unsigned long flags;
 777	DEFINE_WAIT(wait);
 778
 779 retry:
 780	spin_lock_irqsave(ap->lock, flags);
 781
 782	while (ap->pflags & (ATA_PFLAG_EH_PENDING | ATA_PFLAG_EH_IN_PROGRESS)) {
 783		prepare_to_wait(&ap->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 784		spin_unlock_irqrestore(ap->lock, flags);
 785		schedule();
 786		spin_lock_irqsave(ap->lock, flags);
 787	}
 788	finish_wait(&ap->eh_wait_q, &wait);
 789
 790	spin_unlock_irqrestore(ap->lock, flags);
 791
 792	/* make sure SCSI EH is complete */
 793	if (scsi_host_in_recovery(ap->scsi_host)) {
 794		ata_msleep(ap, 10);
 795		goto retry;
 796	}
 797}
 798EXPORT_SYMBOL_GPL(ata_port_wait_eh);
 799
 800static int ata_eh_nr_in_flight(struct ata_port *ap)
 801{
 802	struct ata_queued_cmd *qc;
 803	unsigned int tag;
 804	int nr = 0;
 805
 806	/* count only non-internal commands */
 807	ata_qc_for_each(ap, qc, tag) {
 808		if (qc)
 809			nr++;
 810	}
 811
 812	return nr;
 813}
 814
 815void ata_eh_fastdrain_timerfn(struct timer_list *t)
 816{
 817	struct ata_port *ap = from_timer(ap, t, fastdrain_timer);
 818	unsigned long flags;
 819	int cnt;
 820
 821	spin_lock_irqsave(ap->lock, flags);
 822
 823	cnt = ata_eh_nr_in_flight(ap);
 824
 825	/* are we done? */
 826	if (!cnt)
 827		goto out_unlock;
 828
 829	if (cnt == ap->fastdrain_cnt) {
 830		struct ata_queued_cmd *qc;
 831		unsigned int tag;
 832
 833		/* No progress during the last interval, tag all
 834		 * in-flight qcs as timed out and freeze the port.
 835		 */
 836		ata_qc_for_each(ap, qc, tag) {
 837			if (qc)
 838				qc->err_mask |= AC_ERR_TIMEOUT;
 839		}
 840
 841		ata_port_freeze(ap);
 842	} else {
 843		/* some qcs have finished, give it another chance */
 844		ap->fastdrain_cnt = cnt;
 845		ap->fastdrain_timer.expires =
 846			ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 847		add_timer(&ap->fastdrain_timer);
 848	}
 849
 850 out_unlock:
 851	spin_unlock_irqrestore(ap->lock, flags);
 852}
 853
 854/**
 855 *	ata_eh_set_pending - set ATA_PFLAG_EH_PENDING and activate fast drain
 856 *	@ap: target ATA port
 857 *	@fastdrain: activate fast drain
 858 *
 859 *	Set ATA_PFLAG_EH_PENDING and activate fast drain if @fastdrain
 860 *	is non-zero and EH wasn't pending before.  Fast drain ensures
 861 *	that EH kicks in in timely manner.
 862 *
 863 *	LOCKING:
 864 *	spin_lock_irqsave(host lock)
 865 */
 866static void ata_eh_set_pending(struct ata_port *ap, int fastdrain)
 867{
 868	int cnt;
 869
 870	/* already scheduled? */
 871	if (ap->pflags & ATA_PFLAG_EH_PENDING)
 872		return;
 873
 874	ap->pflags |= ATA_PFLAG_EH_PENDING;
 875
 876	if (!fastdrain)
 877		return;
 878
 879	/* do we have in-flight qcs? */
 880	cnt = ata_eh_nr_in_flight(ap);
 881	if (!cnt)
 882		return;
 883
 884	/* activate fast drain */
 885	ap->fastdrain_cnt = cnt;
 886	ap->fastdrain_timer.expires =
 887		ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 888	add_timer(&ap->fastdrain_timer);
 889}
 890
 891/**
 892 *	ata_qc_schedule_eh - schedule qc for error handling
 893 *	@qc: command to schedule error handling for
 894 *
 895 *	Schedule error handling for @qc.  EH will kick in as soon as
 896 *	other commands are drained.
 897 *
 898 *	LOCKING:
 899 *	spin_lock_irqsave(host lock)
 900 */
 901void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
 902{
 903	struct ata_port *ap = qc->ap;
 904
 905	WARN_ON(!ap->ops->error_handler);
 906
 907	qc->flags |= ATA_QCFLAG_FAILED;
 908	ata_eh_set_pending(ap, 1);
 909
 910	/* The following will fail if timeout has already expired.
 911	 * ata_scsi_error() takes care of such scmds on EH entry.
 912	 * Note that ATA_QCFLAG_FAILED is unconditionally set after
 913	 * this function completes.
 914	 */
 915	blk_abort_request(qc->scsicmd->request);
 916}
 917
 918/**
 919 * ata_std_sched_eh - non-libsas ata_ports issue eh with this common routine
 920 * @ap: ATA port to schedule EH for
 921 *
 922 *	LOCKING: inherited from ata_port_schedule_eh
 923 *	spin_lock_irqsave(host lock)
 924 */
 925void ata_std_sched_eh(struct ata_port *ap)
 926{
 927	WARN_ON(!ap->ops->error_handler);
 928
 929	if (ap->pflags & ATA_PFLAG_INITIALIZING)
 930		return;
 931
 932	ata_eh_set_pending(ap, 1);
 933	scsi_schedule_eh(ap->scsi_host);
 934
 935	DPRINTK("port EH scheduled\n");
 936}
 937EXPORT_SYMBOL_GPL(ata_std_sched_eh);
 938
 939/**
 940 * ata_std_end_eh - non-libsas ata_ports complete eh with this common routine
 941 * @ap: ATA port to end EH for
 942 *
 943 * In the libata object model there is a 1:1 mapping of ata_port to
 944 * shost, so host fields can be directly manipulated under ap->lock, in
 945 * the libsas case we need to hold a lock at the ha->level to coordinate
 946 * these events.
 947 *
 948 *	LOCKING:
 949 *	spin_lock_irqsave(host lock)
 950 */
 951void ata_std_end_eh(struct ata_port *ap)
 952{
 953	struct Scsi_Host *host = ap->scsi_host;
 954
 955	host->host_eh_scheduled = 0;
 956}
 957EXPORT_SYMBOL(ata_std_end_eh);
 958
 959
 960/**
 961 *	ata_port_schedule_eh - schedule error handling without a qc
 962 *	@ap: ATA port to schedule EH for
 963 *
 964 *	Schedule error handling for @ap.  EH will kick in as soon as
 965 *	all commands are drained.
 966 *
 967 *	LOCKING:
 968 *	spin_lock_irqsave(host lock)
 969 */
 970void ata_port_schedule_eh(struct ata_port *ap)
 971{
 972	/* see: ata_std_sched_eh, unless you know better */
 973	ap->ops->sched_eh(ap);
 974}
 975EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
 976
 977static int ata_do_link_abort(struct ata_port *ap, struct ata_link *link)
 978{
 979	struct ata_queued_cmd *qc;
 980	int tag, nr_aborted = 0;
 981
 982	WARN_ON(!ap->ops->error_handler);
 983
 984	/* we're gonna abort all commands, no need for fast drain */
 985	ata_eh_set_pending(ap, 0);
 986
 987	/* include internal tag in iteration */
 988	ata_qc_for_each_with_internal(ap, qc, tag) {
 989		if (qc && (!link || qc->dev->link == link)) {
 990			qc->flags |= ATA_QCFLAG_FAILED;
 991			ata_qc_complete(qc);
 992			nr_aborted++;
 993		}
 994	}
 995
 996	if (!nr_aborted)
 997		ata_port_schedule_eh(ap);
 998
 999	return nr_aborted;
1000}
1001
1002/**
1003 *	ata_link_abort - abort all qc's on the link
1004 *	@link: ATA link to abort qc's for
1005 *
1006 *	Abort all active qc's active on @link and schedule EH.
1007 *
1008 *	LOCKING:
1009 *	spin_lock_irqsave(host lock)
1010 *
1011 *	RETURNS:
1012 *	Number of aborted qc's.
1013 */
1014int ata_link_abort(struct ata_link *link)
1015{
1016	return ata_do_link_abort(link->ap, link);
1017}
1018EXPORT_SYMBOL_GPL(ata_link_abort);
1019
1020/**
1021 *	ata_port_abort - abort all qc's on the port
1022 *	@ap: ATA port to abort qc's for
1023 *
1024 *	Abort all active qc's of @ap and schedule EH.
1025 *
1026 *	LOCKING:
1027 *	spin_lock_irqsave(host_set lock)
1028 *
1029 *	RETURNS:
1030 *	Number of aborted qc's.
1031 */
1032int ata_port_abort(struct ata_port *ap)
1033{
1034	return ata_do_link_abort(ap, NULL);
1035}
1036EXPORT_SYMBOL_GPL(ata_port_abort);
1037
1038/**
1039 *	__ata_port_freeze - freeze port
1040 *	@ap: ATA port to freeze
1041 *
1042 *	This function is called when HSM violation or some other
1043 *	condition disrupts normal operation of the port.  Frozen port
1044 *	is not allowed to perform any operation until the port is
1045 *	thawed, which usually follows a successful reset.
1046 *
1047 *	ap->ops->freeze() callback can be used for freezing the port
1048 *	hardware-wise (e.g. mask interrupt and stop DMA engine).  If a
1049 *	port cannot be frozen hardware-wise, the interrupt handler
1050 *	must ack and clear interrupts unconditionally while the port
1051 *	is frozen.
1052 *
1053 *	LOCKING:
1054 *	spin_lock_irqsave(host lock)
1055 */
1056static void __ata_port_freeze(struct ata_port *ap)
1057{
1058	WARN_ON(!ap->ops->error_handler);
1059
1060	if (ap->ops->freeze)
1061		ap->ops->freeze(ap);
1062
1063	ap->pflags |= ATA_PFLAG_FROZEN;
1064
1065	DPRINTK("ata%u port frozen\n", ap->print_id);
1066}
1067
1068/**
1069 *	ata_port_freeze - abort & freeze port
1070 *	@ap: ATA port to freeze
1071 *
1072 *	Abort and freeze @ap.  The freeze operation must be called
1073 *	first, because some hardware requires special operations
1074 *	before the taskfile registers are accessible.
1075 *
1076 *	LOCKING:
1077 *	spin_lock_irqsave(host lock)
1078 *
1079 *	RETURNS:
1080 *	Number of aborted commands.
1081 */
1082int ata_port_freeze(struct ata_port *ap)
1083{
1084	int nr_aborted;
1085
1086	WARN_ON(!ap->ops->error_handler);
1087
1088	__ata_port_freeze(ap);
1089	nr_aborted = ata_port_abort(ap);
1090
1091	return nr_aborted;
1092}
1093EXPORT_SYMBOL_GPL(ata_port_freeze);
1094
1095/**
1096 *	ata_eh_freeze_port - EH helper to freeze port
1097 *	@ap: ATA port to freeze
1098 *
1099 *	Freeze @ap.
1100 *
1101 *	LOCKING:
1102 *	None.
1103 */
1104void ata_eh_freeze_port(struct ata_port *ap)
1105{
1106	unsigned long flags;
1107
1108	if (!ap->ops->error_handler)
1109		return;
1110
1111	spin_lock_irqsave(ap->lock, flags);
1112	__ata_port_freeze(ap);
1113	spin_unlock_irqrestore(ap->lock, flags);
1114}
1115EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
1116
1117/**
1118 *	ata_eh_thaw_port - EH helper to thaw port
1119 *	@ap: ATA port to thaw
1120 *
1121 *	Thaw frozen port @ap.
1122 *
1123 *	LOCKING:
1124 *	None.
1125 */
1126void ata_eh_thaw_port(struct ata_port *ap)
1127{
1128	unsigned long flags;
1129
1130	if (!ap->ops->error_handler)
1131		return;
1132
1133	spin_lock_irqsave(ap->lock, flags);
1134
1135	ap->pflags &= ~ATA_PFLAG_FROZEN;
1136
1137	if (ap->ops->thaw)
1138		ap->ops->thaw(ap);
1139
1140	spin_unlock_irqrestore(ap->lock, flags);
1141
1142	DPRINTK("ata%u port thawed\n", ap->print_id);
1143}
1144
1145static void ata_eh_scsidone(struct scsi_cmnd *scmd)
1146{
1147	/* nada */
1148}
1149
1150static void __ata_eh_qc_complete(struct ata_queued_cmd *qc)
1151{
1152	struct ata_port *ap = qc->ap;
1153	struct scsi_cmnd *scmd = qc->scsicmd;
1154	unsigned long flags;
1155
1156	spin_lock_irqsave(ap->lock, flags);
1157	qc->scsidone = ata_eh_scsidone;
1158	__ata_qc_complete(qc);
1159	WARN_ON(ata_tag_valid(qc->tag));
1160	spin_unlock_irqrestore(ap->lock, flags);
1161
1162	scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
1163}
1164
1165/**
1166 *	ata_eh_qc_complete - Complete an active ATA command from EH
1167 *	@qc: Command to complete
1168 *
1169 *	Indicate to the mid and upper layers that an ATA command has
1170 *	completed.  To be used from EH.
1171 */
1172void ata_eh_qc_complete(struct ata_queued_cmd *qc)
1173{
1174	struct scsi_cmnd *scmd = qc->scsicmd;
1175	scmd->retries = scmd->allowed;
1176	__ata_eh_qc_complete(qc);
1177}
1178
1179/**
1180 *	ata_eh_qc_retry - Tell midlayer to retry an ATA command after EH
1181 *	@qc: Command to retry
1182 *
1183 *	Indicate to the mid and upper layers that an ATA command
1184 *	should be retried.  To be used from EH.
1185 *
1186 *	SCSI midlayer limits the number of retries to scmd->allowed.
1187 *	scmd->allowed is incremented for commands which get retried
1188 *	due to unrelated failures (qc->err_mask is zero).
1189 */
1190void ata_eh_qc_retry(struct ata_queued_cmd *qc)
1191{
1192	struct scsi_cmnd *scmd = qc->scsicmd;
1193	if (!qc->err_mask)
1194		scmd->allowed++;
1195	__ata_eh_qc_complete(qc);
1196}
1197
1198/**
1199 *	ata_dev_disable - disable ATA device
1200 *	@dev: ATA device to disable
1201 *
1202 *	Disable @dev.
1203 *
1204 *	Locking:
1205 *	EH context.
1206 */
1207void ata_dev_disable(struct ata_device *dev)
1208{
1209	if (!ata_dev_enabled(dev))
1210		return;
1211
1212	if (ata_msg_drv(dev->link->ap))
1213		ata_dev_warn(dev, "disabled\n");
1214	ata_acpi_on_disable(dev);
1215	ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 | ATA_DNXFER_QUIET);
1216	dev->class++;
1217
1218	/* From now till the next successful probe, ering is used to
1219	 * track probe failures.  Clear accumulated device error info.
1220	 */
1221	ata_ering_clear(&dev->ering);
1222}
1223EXPORT_SYMBOL_GPL(ata_dev_disable);
1224
1225/**
1226 *	ata_eh_detach_dev - detach ATA device
1227 *	@dev: ATA device to detach
1228 *
1229 *	Detach @dev.
1230 *
1231 *	LOCKING:
1232 *	None.
1233 */
1234void ata_eh_detach_dev(struct ata_device *dev)
1235{
1236	struct ata_link *link = dev->link;
1237	struct ata_port *ap = link->ap;
1238	struct ata_eh_context *ehc = &link->eh_context;
1239	unsigned long flags;
1240
1241	ata_dev_disable(dev);
1242
1243	spin_lock_irqsave(ap->lock, flags);
1244
1245	dev->flags &= ~ATA_DFLAG_DETACH;
1246
1247	if (ata_scsi_offline_dev(dev)) {
1248		dev->flags |= ATA_DFLAG_DETACHED;
1249		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
1250	}
1251
1252	/* clear per-dev EH info */
1253	ata_eh_clear_action(link, dev, &link->eh_info, ATA_EH_PERDEV_MASK);
1254	ata_eh_clear_action(link, dev, &link->eh_context.i, ATA_EH_PERDEV_MASK);
1255	ehc->saved_xfer_mode[dev->devno] = 0;
1256	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
1257
1258	spin_unlock_irqrestore(ap->lock, flags);
1259}
1260
1261/**
1262 *	ata_eh_about_to_do - about to perform eh_action
1263 *	@link: target ATA link
1264 *	@dev: target ATA dev for per-dev action (can be NULL)
1265 *	@action: action about to be performed
1266 *
1267 *	Called just before performing EH actions to clear related bits
1268 *	in @link->eh_info such that eh actions are not unnecessarily
1269 *	repeated.
1270 *
1271 *	LOCKING:
1272 *	None.
1273 */
1274void ata_eh_about_to_do(struct ata_link *link, struct ata_device *dev,
1275			unsigned int action)
1276{
1277	struct ata_port *ap = link->ap;
1278	struct ata_eh_info *ehi = &link->eh_info;
1279	struct ata_eh_context *ehc = &link->eh_context;
1280	unsigned long flags;
1281
1282	spin_lock_irqsave(ap->lock, flags);
1283
1284	ata_eh_clear_action(link, dev, ehi, action);
1285
1286	/* About to take EH action, set RECOVERED.  Ignore actions on
1287	 * slave links as master will do them again.
1288	 */
1289	if (!(ehc->i.flags & ATA_EHI_QUIET) && link != ap->slave_link)
1290		ap->pflags |= ATA_PFLAG_RECOVERED;
1291
1292	spin_unlock_irqrestore(ap->lock, flags);
1293}
1294
1295/**
1296 *	ata_eh_done - EH action complete
1297 *	@link: ATA link for which EH actions are complete
1298 *	@dev: target ATA dev for per-dev action (can be NULL)
1299 *	@action: action just completed
1300 *
1301 *	Called right after performing EH actions to clear related bits
1302 *	in @link->eh_context.
1303 *
1304 *	LOCKING:
1305 *	None.
1306 */
1307void ata_eh_done(struct ata_link *link, struct ata_device *dev,
1308		 unsigned int action)
1309{
1310	struct ata_eh_context *ehc = &link->eh_context;
1311
1312	ata_eh_clear_action(link, dev, &ehc->i, action);
1313}
1314
1315/**
1316 *	ata_err_string - convert err_mask to descriptive string
1317 *	@err_mask: error mask to convert to string
1318 *
1319 *	Convert @err_mask to descriptive string.  Errors are
1320 *	prioritized according to severity and only the most severe
1321 *	error is reported.
1322 *
1323 *	LOCKING:
1324 *	None.
1325 *
1326 *	RETURNS:
1327 *	Descriptive string for @err_mask
1328 */
1329static const char *ata_err_string(unsigned int err_mask)
1330{
1331	if (err_mask & AC_ERR_HOST_BUS)
1332		return "host bus error";
1333	if (err_mask & AC_ERR_ATA_BUS)
1334		return "ATA bus error";
1335	if (err_mask & AC_ERR_TIMEOUT)
1336		return "timeout";
1337	if (err_mask & AC_ERR_HSM)
1338		return "HSM violation";
1339	if (err_mask & AC_ERR_SYSTEM)
1340		return "internal error";
1341	if (err_mask & AC_ERR_MEDIA)
1342		return "media error";
1343	if (err_mask & AC_ERR_INVALID)
1344		return "invalid argument";
1345	if (err_mask & AC_ERR_DEV)
1346		return "device error";
1347	if (err_mask & AC_ERR_NCQ)
1348		return "NCQ error";
1349	if (err_mask & AC_ERR_NODEV_HINT)
1350		return "Polling detection error";
1351	return "unknown error";
1352}
1353
1354/**
1355 *	atapi_eh_tur - perform ATAPI TEST_UNIT_READY
1356 *	@dev: target ATAPI device
1357 *	@r_sense_key: out parameter for sense_key
1358 *
1359 *	Perform ATAPI TEST_UNIT_READY.
1360 *
1361 *	LOCKING:
1362 *	EH context (may sleep).
1363 *
1364 *	RETURNS:
1365 *	0 on success, AC_ERR_* mask on failure.
1366 */
1367unsigned int atapi_eh_tur(struct ata_device *dev, u8 *r_sense_key)
1368{
1369	u8 cdb[ATAPI_CDB_LEN] = { TEST_UNIT_READY, 0, 0, 0, 0, 0 };
1370	struct ata_taskfile tf;
1371	unsigned int err_mask;
1372
1373	ata_tf_init(dev, &tf);
1374
1375	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1376	tf.command = ATA_CMD_PACKET;
1377	tf.protocol = ATAPI_PROT_NODATA;
1378
1379	err_mask = ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
1380	if (err_mask == AC_ERR_DEV)
1381		*r_sense_key = tf.feature >> 4;
1382	return err_mask;
1383}
1384
1385/**
1386 *	ata_eh_request_sense - perform REQUEST_SENSE_DATA_EXT
1387 *	@qc: qc to perform REQUEST_SENSE_SENSE_DATA_EXT to
1388 *	@cmd: scsi command for which the sense code should be set
1389 *
1390 *	Perform REQUEST_SENSE_DATA_EXT after the device reported CHECK
1391 *	SENSE.  This function is an EH helper.
1392 *
1393 *	LOCKING:
1394 *	Kernel thread context (may sleep).
1395 */
1396static void ata_eh_request_sense(struct ata_queued_cmd *qc,
1397				 struct scsi_cmnd *cmd)
1398{
1399	struct ata_device *dev = qc->dev;
1400	struct ata_taskfile tf;
1401	unsigned int err_mask;
1402
1403	if (qc->ap->pflags & ATA_PFLAG_FROZEN) {
1404		ata_dev_warn(dev, "sense data available but port frozen\n");
1405		return;
1406	}
1407
1408	if (!cmd || qc->flags & ATA_QCFLAG_SENSE_VALID)
1409		return;
1410
1411	if (!ata_id_sense_reporting_enabled(dev->id)) {
1412		ata_dev_warn(qc->dev, "sense data reporting disabled\n");
1413		return;
1414	}
1415
1416	DPRINTK("ATA request sense\n");
1417
1418	ata_tf_init(dev, &tf);
1419	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1420	tf.flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
1421	tf.command = ATA_CMD_REQ_SENSE_DATA;
1422	tf.protocol = ATA_PROT_NODATA;
1423
1424	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1425	/* Ignore err_mask; ATA_ERR might be set */
1426	if (tf.command & ATA_SENSE) {
1427		ata_scsi_set_sense(dev, cmd, tf.lbah, tf.lbam, tf.lbal);
1428		qc->flags |= ATA_QCFLAG_SENSE_VALID;
1429	} else {
1430		ata_dev_warn(dev, "request sense failed stat %02x emask %x\n",
1431			     tf.command, err_mask);
1432	}
1433}
1434
1435/**
1436 *	atapi_eh_request_sense - perform ATAPI REQUEST_SENSE
1437 *	@dev: device to perform REQUEST_SENSE to
1438 *	@sense_buf: result sense data buffer (SCSI_SENSE_BUFFERSIZE bytes long)
1439 *	@dfl_sense_key: default sense key to use
1440 *
1441 *	Perform ATAPI REQUEST_SENSE after the device reported CHECK
1442 *	SENSE.  This function is EH helper.
1443 *
1444 *	LOCKING:
1445 *	Kernel thread context (may sleep).
1446 *
1447 *	RETURNS:
1448 *	0 on success, AC_ERR_* mask on failure
1449 */
1450unsigned int atapi_eh_request_sense(struct ata_device *dev,
1451					   u8 *sense_buf, u8 dfl_sense_key)
1452{
1453	u8 cdb[ATAPI_CDB_LEN] =
1454		{ REQUEST_SENSE, 0, 0, 0, SCSI_SENSE_BUFFERSIZE, 0 };
1455	struct ata_port *ap = dev->link->ap;
1456	struct ata_taskfile tf;
1457
1458	DPRINTK("ATAPI request sense\n");
1459
1460	memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
1461
1462	/* initialize sense_buf with the error register,
1463	 * for the case where they are -not- overwritten
1464	 */
1465	sense_buf[0] = 0x70;
1466	sense_buf[2] = dfl_sense_key;
1467
1468	/* some devices time out if garbage left in tf */
1469	ata_tf_init(dev, &tf);
1470
1471	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1472	tf.command = ATA_CMD_PACKET;
1473
1474	/* is it pointless to prefer PIO for "safety reasons"? */
1475	if (ap->flags & ATA_FLAG_PIO_DMA) {
1476		tf.protocol = ATAPI_PROT_DMA;
1477		tf.feature |= ATAPI_PKT_DMA;
1478	} else {
1479		tf.protocol = ATAPI_PROT_PIO;
1480		tf.lbam = SCSI_SENSE_BUFFERSIZE;
1481		tf.lbah = 0;
1482	}
1483
1484	return ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
1485				 sense_buf, SCSI_SENSE_BUFFERSIZE, 0);
1486}
1487
1488/**
1489 *	ata_eh_analyze_serror - analyze SError for a failed port
1490 *	@link: ATA link to analyze SError for
1491 *
1492 *	Analyze SError if available and further determine cause of
1493 *	failure.
1494 *
1495 *	LOCKING:
1496 *	None.
1497 */
1498static void ata_eh_analyze_serror(struct ata_link *link)
1499{
1500	struct ata_eh_context *ehc = &link->eh_context;
1501	u32 serror = ehc->i.serror;
1502	unsigned int err_mask = 0, action = 0;
1503	u32 hotplug_mask;
1504
1505	if (serror & (SERR_PERSISTENT | SERR_DATA)) {
1506		err_mask |= AC_ERR_ATA_BUS;
1507		action |= ATA_EH_RESET;
1508	}
1509	if (serror & SERR_PROTOCOL) {
1510		err_mask |= AC_ERR_HSM;
1511		action |= ATA_EH_RESET;
1512	}
1513	if (serror & SERR_INTERNAL) {
1514		err_mask |= AC_ERR_SYSTEM;
1515		action |= ATA_EH_RESET;
1516	}
1517
1518	/* Determine whether a hotplug event has occurred.  Both
1519	 * SError.N/X are considered hotplug events for enabled or
1520	 * host links.  For disabled PMP links, only N bit is
1521	 * considered as X bit is left at 1 for link plugging.
1522	 */
1523	if (link->lpm_policy > ATA_LPM_MAX_POWER)
1524		hotplug_mask = 0;	/* hotplug doesn't work w/ LPM */
1525	else if (!(link->flags & ATA_LFLAG_DISABLED) || ata_is_host_link(link))
1526		hotplug_mask = SERR_PHYRDY_CHG | SERR_DEV_XCHG;
1527	else
1528		hotplug_mask = SERR_PHYRDY_CHG;
1529
1530	if (serror & hotplug_mask)
1531		ata_ehi_hotplugged(&ehc->i);
1532
1533	ehc->i.err_mask |= err_mask;
1534	ehc->i.action |= action;
1535}
1536
1537/**
1538 *	ata_eh_analyze_tf - analyze taskfile of a failed qc
1539 *	@qc: qc to analyze
1540 *	@tf: Taskfile registers to analyze
1541 *
1542 *	Analyze taskfile of @qc and further determine cause of
1543 *	failure.  This function also requests ATAPI sense data if
1544 *	available.
1545 *
1546 *	LOCKING:
1547 *	Kernel thread context (may sleep).
1548 *
1549 *	RETURNS:
1550 *	Determined recovery action
1551 */
1552static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc,
1553				      const struct ata_taskfile *tf)
1554{
1555	unsigned int tmp, action = 0;
1556	u8 stat = tf->command, err = tf->feature;
1557
1558	if ((stat & (ATA_BUSY | ATA_DRQ | ATA_DRDY)) != ATA_DRDY) {
1559		qc->err_mask |= AC_ERR_HSM;
1560		return ATA_EH_RESET;
1561	}
1562
1563	if (stat & (ATA_ERR | ATA_DF)) {
1564		qc->err_mask |= AC_ERR_DEV;
1565		/*
1566		 * Sense data reporting does not work if the
1567		 * device fault bit is set.
1568		 */
1569		if (stat & ATA_DF)
1570			stat &= ~ATA_SENSE;
1571	} else {
1572		return 0;
1573	}
1574
1575	switch (qc->dev->class) {
1576	case ATA_DEV_ZAC:
1577		if (stat & ATA_SENSE)
1578			ata_eh_request_sense(qc, qc->scsicmd);
1579		fallthrough;
1580	case ATA_DEV_ATA:
1581		if (err & ATA_ICRC)
1582			qc->err_mask |= AC_ERR_ATA_BUS;
1583		if (err & (ATA_UNC | ATA_AMNF))
1584			qc->err_mask |= AC_ERR_MEDIA;
1585		if (err & ATA_IDNF)
1586			qc->err_mask |= AC_ERR_INVALID;
1587		break;
1588
1589	case ATA_DEV_ATAPI:
1590		if (!(qc->ap->pflags & ATA_PFLAG_FROZEN)) {
1591			tmp = atapi_eh_request_sense(qc->dev,
1592						qc->scsicmd->sense_buffer,
1593						qc->result_tf.feature >> 4);
1594			if (!tmp)
1595				qc->flags |= ATA_QCFLAG_SENSE_VALID;
1596			else
1597				qc->err_mask |= tmp;
1598		}
1599	}
1600
1601	if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
1602		enum scsi_disposition ret = scsi_check_sense(qc->scsicmd);
1603		/*
1604		 * SUCCESS here means that the sense code could be
1605		 * evaluated and should be passed to the upper layers
1606		 * for correct evaluation.
1607		 * FAILED means the sense code could not be interpreted
1608		 * and the device would need to be reset.
1609		 * NEEDS_RETRY and ADD_TO_MLQUEUE means that the
1610		 * command would need to be retried.
1611		 */
1612		if (ret == NEEDS_RETRY || ret == ADD_TO_MLQUEUE) {
1613			qc->flags |= ATA_QCFLAG_RETRY;
1614			qc->err_mask |= AC_ERR_OTHER;
1615		} else if (ret != SUCCESS) {
1616			qc->err_mask |= AC_ERR_HSM;
1617		}
1618	}
1619	if (qc->err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT | AC_ERR_ATA_BUS))
1620		action |= ATA_EH_RESET;
1621
1622	return action;
1623}
1624
1625static int ata_eh_categorize_error(unsigned int eflags, unsigned int err_mask,
1626				   int *xfer_ok)
1627{
1628	int base = 0;
1629
1630	if (!(eflags & ATA_EFLAG_DUBIOUS_XFER))
1631		*xfer_ok = 1;
1632
1633	if (!*xfer_ok)
1634		base = ATA_ECAT_DUBIOUS_NONE;
1635
1636	if (err_mask & AC_ERR_ATA_BUS)
1637		return base + ATA_ECAT_ATA_BUS;
1638
1639	if (err_mask & AC_ERR_TIMEOUT)
1640		return base + ATA_ECAT_TOUT_HSM;
1641
1642	if (eflags & ATA_EFLAG_IS_IO) {
1643		if (err_mask & AC_ERR_HSM)
1644			return base + ATA_ECAT_TOUT_HSM;
1645		if ((err_mask &
1646		     (AC_ERR_DEV|AC_ERR_MEDIA|AC_ERR_INVALID)) == AC_ERR_DEV)
1647			return base + ATA_ECAT_UNK_DEV;
1648	}
1649
1650	return 0;
1651}
1652
1653struct speed_down_verdict_arg {
1654	u64 since;
1655	int xfer_ok;
1656	int nr_errors[ATA_ECAT_NR];
1657};
1658
1659static int speed_down_verdict_cb(struct ata_ering_entry *ent, void *void_arg)
1660{
1661	struct speed_down_verdict_arg *arg = void_arg;
1662	int cat;
1663
1664	if ((ent->eflags & ATA_EFLAG_OLD_ER) || (ent->timestamp < arg->since))
1665		return -1;
1666
1667	cat = ata_eh_categorize_error(ent->eflags, ent->err_mask,
1668				      &arg->xfer_ok);
1669	arg->nr_errors[cat]++;
1670
1671	return 0;
1672}
1673
1674/**
1675 *	ata_eh_speed_down_verdict - Determine speed down verdict
1676 *	@dev: Device of interest
1677 *
1678 *	This function examines error ring of @dev and determines
1679 *	whether NCQ needs to be turned off, transfer speed should be
1680 *	stepped down, or falling back to PIO is necessary.
1681 *
1682 *	ECAT_ATA_BUS	: ATA_BUS error for any command
1683 *
1684 *	ECAT_TOUT_HSM	: TIMEOUT for any command or HSM violation for
1685 *			  IO commands
1686 *
1687 *	ECAT_UNK_DEV	: Unknown DEV error for IO commands
1688 *
1689 *	ECAT_DUBIOUS_*	: Identical to above three but occurred while
1690 *			  data transfer hasn't been verified.
1691 *
1692 *	Verdicts are
1693 *
1694 *	NCQ_OFF		: Turn off NCQ.
1695 *
1696 *	SPEED_DOWN	: Speed down transfer speed but don't fall back
1697 *			  to PIO.
1698 *
1699 *	FALLBACK_TO_PIO	: Fall back to PIO.
1700 *
1701 *	Even if multiple verdicts are returned, only one action is
1702 *	taken per error.  An action triggered by non-DUBIOUS errors
1703 *	clears ering, while one triggered by DUBIOUS_* errors doesn't.
1704 *	This is to expedite speed down decisions right after device is
1705 *	initially configured.
1706 *
1707 *	The following are speed down rules.  #1 and #2 deal with
1708 *	DUBIOUS errors.
1709 *
1710 *	1. If more than one DUBIOUS_ATA_BUS or DUBIOUS_TOUT_HSM errors
1711 *	   occurred during last 5 mins, SPEED_DOWN and FALLBACK_TO_PIO.
1712 *
1713 *	2. If more than one DUBIOUS_TOUT_HSM or DUBIOUS_UNK_DEV errors
1714 *	   occurred during last 5 mins, NCQ_OFF.
1715 *
1716 *	3. If more than 8 ATA_BUS, TOUT_HSM or UNK_DEV errors
1717 *	   occurred during last 5 mins, FALLBACK_TO_PIO
1718 *
1719 *	4. If more than 3 TOUT_HSM or UNK_DEV errors occurred
1720 *	   during last 10 mins, NCQ_OFF.
1721 *
1722 *	5. If more than 3 ATA_BUS or TOUT_HSM errors, or more than 6
1723 *	   UNK_DEV errors occurred during last 10 mins, SPEED_DOWN.
1724 *
1725 *	LOCKING:
1726 *	Inherited from caller.
1727 *
1728 *	RETURNS:
1729 *	OR of ATA_EH_SPDN_* flags.
1730 */
1731static unsigned int ata_eh_speed_down_verdict(struct ata_device *dev)
1732{
1733	const u64 j5mins = 5LLU * 60 * HZ, j10mins = 10LLU * 60 * HZ;
1734	u64 j64 = get_jiffies_64();
1735	struct speed_down_verdict_arg arg;
1736	unsigned int verdict = 0;
1737
1738	/* scan past 5 mins of error history */
1739	memset(&arg, 0, sizeof(arg));
1740	arg.since = j64 - min(j64, j5mins);
1741	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1742
1743	if (arg.nr_errors[ATA_ECAT_DUBIOUS_ATA_BUS] +
1744	    arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] > 1)
1745		verdict |= ATA_EH_SPDN_SPEED_DOWN |
1746			ATA_EH_SPDN_FALLBACK_TO_PIO | ATA_EH_SPDN_KEEP_ERRORS;
1747
1748	if (arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] +
1749	    arg.nr_errors[ATA_ECAT_DUBIOUS_UNK_DEV] > 1)
1750		verdict |= ATA_EH_SPDN_NCQ_OFF | ATA_EH_SPDN_KEEP_ERRORS;
1751
1752	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1753	    arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1754	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1755		verdict |= ATA_EH_SPDN_FALLBACK_TO_PIO;
1756
1757	/* scan past 10 mins of error history */
1758	memset(&arg, 0, sizeof(arg));
1759	arg.since = j64 - min(j64, j10mins);
1760	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1761
1762	if (arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1763	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 3)
1764		verdict |= ATA_EH_SPDN_NCQ_OFF;
1765
1766	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1767	    arg.nr_errors[ATA_ECAT_TOUT_HSM] > 3 ||
1768	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1769		verdict |= ATA_EH_SPDN_SPEED_DOWN;
1770
1771	return verdict;
1772}
1773
1774/**
1775 *	ata_eh_speed_down - record error and speed down if necessary
1776 *	@dev: Failed device
1777 *	@eflags: mask of ATA_EFLAG_* flags
1778 *	@err_mask: err_mask of the error
1779 *
1780 *	Record error and examine error history to determine whether
1781 *	adjusting transmission speed is necessary.  It also sets
1782 *	transmission limits appropriately if such adjustment is
1783 *	necessary.
1784 *
1785 *	LOCKING:
1786 *	Kernel thread context (may sleep).
1787 *
1788 *	RETURNS:
1789 *	Determined recovery action.
1790 */
1791static unsigned int ata_eh_speed_down(struct ata_device *dev,
1792				unsigned int eflags, unsigned int err_mask)
1793{
1794	struct ata_link *link = ata_dev_phys_link(dev);
1795	int xfer_ok = 0;
1796	unsigned int verdict;
1797	unsigned int action = 0;
1798
1799	/* don't bother if Cat-0 error */
1800	if (ata_eh_categorize_error(eflags, err_mask, &xfer_ok) == 0)
1801		return 0;
1802
1803	/* record error and determine whether speed down is necessary */
1804	ata_ering_record(&dev->ering, eflags, err_mask);
1805	verdict = ata_eh_speed_down_verdict(dev);
1806
1807	/* turn off NCQ? */
1808	if ((verdict & ATA_EH_SPDN_NCQ_OFF) &&
1809	    (dev->flags & (ATA_DFLAG_PIO | ATA_DFLAG_NCQ |
1810			   ATA_DFLAG_NCQ_OFF)) == ATA_DFLAG_NCQ) {
1811		dev->flags |= ATA_DFLAG_NCQ_OFF;
1812		ata_dev_warn(dev, "NCQ disabled due to excessive errors\n");
1813		goto done;
1814	}
1815
1816	/* speed down? */
1817	if (verdict & ATA_EH_SPDN_SPEED_DOWN) {
1818		/* speed down SATA link speed if possible */
1819		if (sata_down_spd_limit(link, 0) == 0) {
1820			action |= ATA_EH_RESET;
1821			goto done;
1822		}
1823
1824		/* lower transfer mode */
1825		if (dev->spdn_cnt < 2) {
1826			static const int dma_dnxfer_sel[] =
1827				{ ATA_DNXFER_DMA, ATA_DNXFER_40C };
1828			static const int pio_dnxfer_sel[] =
1829				{ ATA_DNXFER_PIO, ATA_DNXFER_FORCE_PIO0 };
1830			int sel;
1831
1832			if (dev->xfer_shift != ATA_SHIFT_PIO)
1833				sel = dma_dnxfer_sel[dev->spdn_cnt];
1834			else
1835				sel = pio_dnxfer_sel[dev->spdn_cnt];
1836
1837			dev->spdn_cnt++;
1838
1839			if (ata_down_xfermask_limit(dev, sel) == 0) {
1840				action |= ATA_EH_RESET;
1841				goto done;
1842			}
1843		}
1844	}
1845
1846	/* Fall back to PIO?  Slowing down to PIO is meaningless for
1847	 * SATA ATA devices.  Consider it only for PATA and SATAPI.
1848	 */
1849	if ((verdict & ATA_EH_SPDN_FALLBACK_TO_PIO) && (dev->spdn_cnt >= 2) &&
1850	    (link->ap->cbl != ATA_CBL_SATA || dev->class == ATA_DEV_ATAPI) &&
1851	    (dev->xfer_shift != ATA_SHIFT_PIO)) {
1852		if (ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO) == 0) {
1853			dev->spdn_cnt = 0;
1854			action |= ATA_EH_RESET;
1855			goto done;
1856		}
1857	}
1858
1859	return 0;
1860 done:
1861	/* device has been slowed down, blow error history */
1862	if (!(verdict & ATA_EH_SPDN_KEEP_ERRORS))
1863		ata_ering_clear(&dev->ering);
1864	return action;
1865}
1866
1867/**
1868 *	ata_eh_worth_retry - analyze error and decide whether to retry
1869 *	@qc: qc to possibly retry
1870 *
1871 *	Look at the cause of the error and decide if a retry
1872 * 	might be useful or not.  We don't want to retry media errors
1873 *	because the drive itself has probably already taken 10-30 seconds
1874 *	doing its own internal retries before reporting the failure.
1875 */
1876static inline int ata_eh_worth_retry(struct ata_queued_cmd *qc)
1877{
1878	if (qc->err_mask & AC_ERR_MEDIA)
1879		return 0;	/* don't retry media errors */
1880	if (qc->flags & ATA_QCFLAG_IO)
1881		return 1;	/* otherwise retry anything from fs stack */
1882	if (qc->err_mask & AC_ERR_INVALID)
1883		return 0;	/* don't retry these */
1884	return qc->err_mask != AC_ERR_DEV;  /* retry if not dev error */
1885}
1886
1887/**
1888 *      ata_eh_quiet - check if we need to be quiet about a command error
1889 *      @qc: qc to check
1890 *
1891 *      Look at the qc flags anbd its scsi command request flags to determine
1892 *      if we need to be quiet about the command failure.
1893 */
1894static inline bool ata_eh_quiet(struct ata_queued_cmd *qc)
1895{
1896	if (qc->scsicmd &&
1897	    qc->scsicmd->request->rq_flags & RQF_QUIET)
1898		qc->flags |= ATA_QCFLAG_QUIET;
1899	return qc->flags & ATA_QCFLAG_QUIET;
1900}
1901
1902/**
1903 *	ata_eh_link_autopsy - analyze error and determine recovery action
1904 *	@link: host link to perform autopsy on
1905 *
1906 *	Analyze why @link failed and determine which recovery actions
1907 *	are needed.  This function also sets more detailed AC_ERR_*
1908 *	values and fills sense data for ATAPI CHECK SENSE.
1909 *
1910 *	LOCKING:
1911 *	Kernel thread context (may sleep).
1912 */
1913static void ata_eh_link_autopsy(struct ata_link *link)
1914{
1915	struct ata_port *ap = link->ap;
1916	struct ata_eh_context *ehc = &link->eh_context;
1917	struct ata_queued_cmd *qc;
1918	struct ata_device *dev;
1919	unsigned int all_err_mask = 0, eflags = 0;
1920	int tag, nr_failed = 0, nr_quiet = 0;
1921	u32 serror;
1922	int rc;
1923
1924	DPRINTK("ENTER\n");
1925
1926	if (ehc->i.flags & ATA_EHI_NO_AUTOPSY)
1927		return;
1928
1929	/* obtain and analyze SError */
1930	rc = sata_scr_read(link, SCR_ERROR, &serror);
1931	if (rc == 0) {
1932		ehc->i.serror |= serror;
1933		ata_eh_analyze_serror(link);
1934	} else if (rc != -EOPNOTSUPP) {
1935		/* SError read failed, force reset and probing */
1936		ehc->i.probe_mask |= ATA_ALL_DEVICES;
1937		ehc->i.action |= ATA_EH_RESET;
1938		ehc->i.err_mask |= AC_ERR_OTHER;
1939	}
1940
1941	/* analyze NCQ failure */
1942	ata_eh_analyze_ncq_error(link);
1943
1944	/* any real error trumps AC_ERR_OTHER */
1945	if (ehc->i.err_mask & ~AC_ERR_OTHER)
1946		ehc->i.err_mask &= ~AC_ERR_OTHER;
1947
1948	all_err_mask |= ehc->i.err_mask;
1949
1950	ata_qc_for_each_raw(ap, qc, tag) {
1951		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
1952		    ata_dev_phys_link(qc->dev) != link)
1953			continue;
1954
1955		/* inherit upper level err_mask */
1956		qc->err_mask |= ehc->i.err_mask;
1957
1958		/* analyze TF */
1959		ehc->i.action |= ata_eh_analyze_tf(qc, &qc->result_tf);
1960
1961		/* DEV errors are probably spurious in case of ATA_BUS error */
1962		if (qc->err_mask & AC_ERR_ATA_BUS)
1963			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_MEDIA |
1964					  AC_ERR_INVALID);
1965
1966		/* any real error trumps unknown error */
1967		if (qc->err_mask & ~AC_ERR_OTHER)
1968			qc->err_mask &= ~AC_ERR_OTHER;
1969
1970		/*
1971		 * SENSE_VALID trumps dev/unknown error and revalidation. Upper
1972		 * layers will determine whether the command is worth retrying
1973		 * based on the sense data and device class/type. Otherwise,
1974		 * determine directly if the command is worth retrying using its
1975		 * error mask and flags.
1976		 */
1977		if (qc->flags & ATA_QCFLAG_SENSE_VALID)
1978			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_OTHER);
1979		else if (ata_eh_worth_retry(qc))
1980			qc->flags |= ATA_QCFLAG_RETRY;
1981
1982		/* accumulate error info */
1983		ehc->i.dev = qc->dev;
1984		all_err_mask |= qc->err_mask;
1985		if (qc->flags & ATA_QCFLAG_IO)
1986			eflags |= ATA_EFLAG_IS_IO;
1987		trace_ata_eh_link_autopsy_qc(qc);
1988
1989		/* Count quiet errors */
1990		if (ata_eh_quiet(qc))
1991			nr_quiet++;
1992		nr_failed++;
1993	}
1994
1995	/* If all failed commands requested silence, then be quiet */
1996	if (nr_quiet == nr_failed)
1997		ehc->i.flags |= ATA_EHI_QUIET;
1998
1999	/* enforce default EH actions */
2000	if (ap->pflags & ATA_PFLAG_FROZEN ||
2001	    all_err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT))
2002		ehc->i.action |= ATA_EH_RESET;
2003	else if (((eflags & ATA_EFLAG_IS_IO) && all_err_mask) ||
2004		 (!(eflags & ATA_EFLAG_IS_IO) && (all_err_mask & ~AC_ERR_DEV)))
2005		ehc->i.action |= ATA_EH_REVALIDATE;
2006
2007	/* If we have offending qcs and the associated failed device,
2008	 * perform per-dev EH action only on the offending device.
2009	 */
2010	if (ehc->i.dev) {
2011		ehc->i.dev_action[ehc->i.dev->devno] |=
2012			ehc->i.action & ATA_EH_PERDEV_MASK;
2013		ehc->i.action &= ~ATA_EH_PERDEV_MASK;
2014	}
2015
2016	/* propagate timeout to host link */
2017	if ((all_err_mask & AC_ERR_TIMEOUT) && !ata_is_host_link(link))
2018		ap->link.eh_context.i.err_mask |= AC_ERR_TIMEOUT;
2019
2020	/* record error and consider speeding down */
2021	dev = ehc->i.dev;
2022	if (!dev && ((ata_link_max_devices(link) == 1 &&
2023		      ata_dev_enabled(link->device))))
2024	    dev = link->device;
2025
2026	if (dev) {
2027		if (dev->flags & ATA_DFLAG_DUBIOUS_XFER)
2028			eflags |= ATA_EFLAG_DUBIOUS_XFER;
2029		ehc->i.action |= ata_eh_speed_down(dev, eflags, all_err_mask);
2030		trace_ata_eh_link_autopsy(dev, ehc->i.action, all_err_mask);
2031	}
2032	DPRINTK("EXIT\n");
2033}
2034
2035/**
2036 *	ata_eh_autopsy - analyze error and determine recovery action
2037 *	@ap: host port to perform autopsy on
2038 *
2039 *	Analyze all links of @ap and determine why they failed and
2040 *	which recovery actions are needed.
2041 *
2042 *	LOCKING:
2043 *	Kernel thread context (may sleep).
2044 */
2045void ata_eh_autopsy(struct ata_port *ap)
2046{
2047	struct ata_link *link;
2048
2049	ata_for_each_link(link, ap, EDGE)
2050		ata_eh_link_autopsy(link);
2051
2052	/* Handle the frigging slave link.  Autopsy is done similarly
2053	 * but actions and flags are transferred over to the master
2054	 * link and handled from there.
2055	 */
2056	if (ap->slave_link) {
2057		struct ata_eh_context *mehc = &ap->link.eh_context;
2058		struct ata_eh_context *sehc = &ap->slave_link->eh_context;
2059
2060		/* transfer control flags from master to slave */
2061		sehc->i.flags |= mehc->i.flags & ATA_EHI_TO_SLAVE_MASK;
2062
2063		/* perform autopsy on the slave link */
2064		ata_eh_link_autopsy(ap->slave_link);
2065
2066		/* transfer actions from slave to master and clear slave */
2067		ata_eh_about_to_do(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2068		mehc->i.action		|= sehc->i.action;
2069		mehc->i.dev_action[1]	|= sehc->i.dev_action[1];
2070		mehc->i.flags		|= sehc->i.flags;
2071		ata_eh_done(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2072	}
2073
2074	/* Autopsy of fanout ports can affect host link autopsy.
2075	 * Perform host link autopsy last.
2076	 */
2077	if (sata_pmp_attached(ap))
2078		ata_eh_link_autopsy(&ap->link);
2079}
2080
2081/**
2082 *	ata_get_cmd_descript - get description for ATA command
2083 *	@command: ATA command code to get description for
2084 *
2085 *	Return a textual description of the given command, or NULL if the
2086 *	command is not known.
2087 *
2088 *	LOCKING:
2089 *	None
2090 */
2091const char *ata_get_cmd_descript(u8 command)
2092{
2093#ifdef CONFIG_ATA_VERBOSE_ERROR
2094	static const struct
2095	{
2096		u8 command;
2097		const char *text;
2098	} cmd_descr[] = {
2099		{ ATA_CMD_DEV_RESET,		"DEVICE RESET" },
2100		{ ATA_CMD_CHK_POWER,		"CHECK POWER MODE" },
2101		{ ATA_CMD_STANDBY,		"STANDBY" },
2102		{ ATA_CMD_IDLE,			"IDLE" },
2103		{ ATA_CMD_EDD,			"EXECUTE DEVICE DIAGNOSTIC" },
2104		{ ATA_CMD_DOWNLOAD_MICRO,	"DOWNLOAD MICROCODE" },
2105		{ ATA_CMD_DOWNLOAD_MICRO_DMA,	"DOWNLOAD MICROCODE DMA" },
2106		{ ATA_CMD_NOP,			"NOP" },
2107		{ ATA_CMD_FLUSH,		"FLUSH CACHE" },
2108		{ ATA_CMD_FLUSH_EXT,		"FLUSH CACHE EXT" },
2109		{ ATA_CMD_ID_ATA,		"IDENTIFY DEVICE" },
2110		{ ATA_CMD_ID_ATAPI,		"IDENTIFY PACKET DEVICE" },
2111		{ ATA_CMD_SERVICE,		"SERVICE" },
2112		{ ATA_CMD_READ,			"READ DMA" },
2113		{ ATA_CMD_READ_EXT,		"READ DMA EXT" },
2114		{ ATA_CMD_READ_QUEUED,		"READ DMA QUEUED" },
2115		{ ATA_CMD_READ_STREAM_EXT,	"READ STREAM EXT" },
2116		{ ATA_CMD_READ_STREAM_DMA_EXT,  "READ STREAM DMA EXT" },
2117		{ ATA_CMD_WRITE,		"WRITE DMA" },
2118		{ ATA_CMD_WRITE_EXT,		"WRITE DMA EXT" },
2119		{ ATA_CMD_WRITE_QUEUED,		"WRITE DMA QUEUED EXT" },
2120		{ ATA_CMD_WRITE_STREAM_EXT,	"WRITE STREAM EXT" },
2121		{ ATA_CMD_WRITE_STREAM_DMA_EXT, "WRITE STREAM DMA EXT" },
2122		{ ATA_CMD_WRITE_FUA_EXT,	"WRITE DMA FUA EXT" },
2123		{ ATA_CMD_WRITE_QUEUED_FUA_EXT, "WRITE DMA QUEUED FUA EXT" },
2124		{ ATA_CMD_FPDMA_READ,		"READ FPDMA QUEUED" },
2125		{ ATA_CMD_FPDMA_WRITE,		"WRITE FPDMA QUEUED" },
2126		{ ATA_CMD_FPDMA_SEND,		"SEND FPDMA QUEUED" },
2127		{ ATA_CMD_FPDMA_RECV,		"RECEIVE FPDMA QUEUED" },
2128		{ ATA_CMD_PIO_READ,		"READ SECTOR(S)" },
2129		{ ATA_CMD_PIO_READ_EXT,		"READ SECTOR(S) EXT" },
2130		{ ATA_CMD_PIO_WRITE,		"WRITE SECTOR(S)" },
2131		{ ATA_CMD_PIO_WRITE_EXT,	"WRITE SECTOR(S) EXT" },
2132		{ ATA_CMD_READ_MULTI,		"READ MULTIPLE" },
2133		{ ATA_CMD_READ_MULTI_EXT,	"READ MULTIPLE EXT" },
2134		{ ATA_CMD_WRITE_MULTI,		"WRITE MULTIPLE" },
2135		{ ATA_CMD_WRITE_MULTI_EXT,	"WRITE MULTIPLE EXT" },
2136		{ ATA_CMD_WRITE_MULTI_FUA_EXT,	"WRITE MULTIPLE FUA EXT" },
2137		{ ATA_CMD_SET_FEATURES,		"SET FEATURES" },
2138		{ ATA_CMD_SET_MULTI,		"SET MULTIPLE MODE" },
2139		{ ATA_CMD_VERIFY,		"READ VERIFY SECTOR(S)" },
2140		{ ATA_CMD_VERIFY_EXT,		"READ VERIFY SECTOR(S) EXT" },
2141		{ ATA_CMD_WRITE_UNCORR_EXT,	"WRITE UNCORRECTABLE EXT" },
2142		{ ATA_CMD_STANDBYNOW1,		"STANDBY IMMEDIATE" },
2143		{ ATA_CMD_IDLEIMMEDIATE,	"IDLE IMMEDIATE" },
2144		{ ATA_CMD_SLEEP,		"SLEEP" },
2145		{ ATA_CMD_INIT_DEV_PARAMS,	"INITIALIZE DEVICE PARAMETERS" },
2146		{ ATA_CMD_READ_NATIVE_MAX,	"READ NATIVE MAX ADDRESS" },
2147		{ ATA_CMD_READ_NATIVE_MAX_EXT,	"READ NATIVE MAX ADDRESS EXT" },
2148		{ ATA_CMD_SET_MAX,		"SET MAX ADDRESS" },
2149		{ ATA_CMD_SET_MAX_EXT,		"SET MAX ADDRESS EXT" },
2150		{ ATA_CMD_READ_LOG_EXT,		"READ LOG EXT" },
2151		{ ATA_CMD_WRITE_LOG_EXT,	"WRITE LOG EXT" },
2152		{ ATA_CMD_READ_LOG_DMA_EXT,	"READ LOG DMA EXT" },
2153		{ ATA_CMD_WRITE_LOG_DMA_EXT,	"WRITE LOG DMA EXT" },
2154		{ ATA_CMD_TRUSTED_NONDATA,	"TRUSTED NON-DATA" },
2155		{ ATA_CMD_TRUSTED_RCV,		"TRUSTED RECEIVE" },
2156		{ ATA_CMD_TRUSTED_RCV_DMA,	"TRUSTED RECEIVE DMA" },
2157		{ ATA_CMD_TRUSTED_SND,		"TRUSTED SEND" },
2158		{ ATA_CMD_TRUSTED_SND_DMA,	"TRUSTED SEND DMA" },
2159		{ ATA_CMD_PMP_READ,		"READ BUFFER" },
2160		{ ATA_CMD_PMP_READ_DMA,		"READ BUFFER DMA" },
2161		{ ATA_CMD_PMP_WRITE,		"WRITE BUFFER" },
2162		{ ATA_CMD_PMP_WRITE_DMA,	"WRITE BUFFER DMA" },
2163		{ ATA_CMD_CONF_OVERLAY,		"DEVICE CONFIGURATION OVERLAY" },
2164		{ ATA_CMD_SEC_SET_PASS,		"SECURITY SET PASSWORD" },
2165		{ ATA_CMD_SEC_UNLOCK,		"SECURITY UNLOCK" },
2166		{ ATA_CMD_SEC_ERASE_PREP,	"SECURITY ERASE PREPARE" },
2167		{ ATA_CMD_SEC_ERASE_UNIT,	"SECURITY ERASE UNIT" },
2168		{ ATA_CMD_SEC_FREEZE_LOCK,	"SECURITY FREEZE LOCK" },
2169		{ ATA_CMD_SEC_DISABLE_PASS,	"SECURITY DISABLE PASSWORD" },
2170		{ ATA_CMD_CONFIG_STREAM,	"CONFIGURE STREAM" },
2171		{ ATA_CMD_SMART,		"SMART" },
2172		{ ATA_CMD_MEDIA_LOCK,		"DOOR LOCK" },
2173		{ ATA_CMD_MEDIA_UNLOCK,		"DOOR UNLOCK" },
2174		{ ATA_CMD_DSM,			"DATA SET MANAGEMENT" },
2175		{ ATA_CMD_CHK_MED_CRD_TYP,	"CHECK MEDIA CARD TYPE" },
2176		{ ATA_CMD_CFA_REQ_EXT_ERR,	"CFA REQUEST EXTENDED ERROR" },
2177		{ ATA_CMD_CFA_WRITE_NE,		"CFA WRITE SECTORS WITHOUT ERASE" },
2178		{ ATA_CMD_CFA_TRANS_SECT,	"CFA TRANSLATE SECTOR" },
2179		{ ATA_CMD_CFA_ERASE,		"CFA ERASE SECTORS" },
2180		{ ATA_CMD_CFA_WRITE_MULT_NE,	"CFA WRITE MULTIPLE WITHOUT ERASE" },
2181		{ ATA_CMD_REQ_SENSE_DATA,	"REQUEST SENSE DATA EXT" },
2182		{ ATA_CMD_SANITIZE_DEVICE,	"SANITIZE DEVICE" },
2183		{ ATA_CMD_ZAC_MGMT_IN,		"ZAC MANAGEMENT IN" },
2184		{ ATA_CMD_ZAC_MGMT_OUT,		"ZAC MANAGEMENT OUT" },
2185		{ ATA_CMD_READ_LONG,		"READ LONG (with retries)" },
2186		{ ATA_CMD_READ_LONG_ONCE,	"READ LONG (without retries)" },
2187		{ ATA_CMD_WRITE_LONG,		"WRITE LONG (with retries)" },
2188		{ ATA_CMD_WRITE_LONG_ONCE,	"WRITE LONG (without retries)" },
2189		{ ATA_CMD_RESTORE,		"RECALIBRATE" },
2190		{ 0,				NULL } /* terminate list */
2191	};
2192
2193	unsigned int i;
2194	for (i = 0; cmd_descr[i].text; i++)
2195		if (cmd_descr[i].command == command)
2196			return cmd_descr[i].text;
2197#endif
2198
2199	return NULL;
2200}
2201EXPORT_SYMBOL_GPL(ata_get_cmd_descript);
2202
2203/**
2204 *	ata_eh_link_report - report error handling to user
2205 *	@link: ATA link EH is going on
2206 *
2207 *	Report EH to user.
2208 *
2209 *	LOCKING:
2210 *	None.
2211 */
2212static void ata_eh_link_report(struct ata_link *link)
2213{
2214	struct ata_port *ap = link->ap;
2215	struct ata_eh_context *ehc = &link->eh_context;
2216	struct ata_queued_cmd *qc;
2217	const char *frozen, *desc;
2218	char tries_buf[6] = "";
2219	int tag, nr_failed = 0;
2220
2221	if (ehc->i.flags & ATA_EHI_QUIET)
2222		return;
2223
2224	desc = NULL;
2225	if (ehc->i.desc[0] != '\0')
2226		desc = ehc->i.desc;
2227
2228	ata_qc_for_each_raw(ap, qc, tag) {
2229		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2230		    ata_dev_phys_link(qc->dev) != link ||
2231		    ((qc->flags & ATA_QCFLAG_QUIET) &&
2232		     qc->err_mask == AC_ERR_DEV))
2233			continue;
2234		if (qc->flags & ATA_QCFLAG_SENSE_VALID && !qc->err_mask)
2235			continue;
2236
2237		nr_failed++;
2238	}
2239
2240	if (!nr_failed && !ehc->i.err_mask)
2241		return;
2242
2243	frozen = "";
2244	if (ap->pflags & ATA_PFLAG_FROZEN)
2245		frozen = " frozen";
2246
2247	if (ap->eh_tries < ATA_EH_MAX_TRIES)
2248		snprintf(tries_buf, sizeof(tries_buf), " t%d",
2249			 ap->eh_tries);
2250
2251	if (ehc->i.dev) {
2252		ata_dev_err(ehc->i.dev, "exception Emask 0x%x "
2253			    "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2254			    ehc->i.err_mask, link->sactive, ehc->i.serror,
2255			    ehc->i.action, frozen, tries_buf);
2256		if (desc)
2257			ata_dev_err(ehc->i.dev, "%s\n", desc);
2258	} else {
2259		ata_link_err(link, "exception Emask 0x%x "
2260			     "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2261			     ehc->i.err_mask, link->sactive, ehc->i.serror,
2262			     ehc->i.action, frozen, tries_buf);
2263		if (desc)
2264			ata_link_err(link, "%s\n", desc);
2265	}
2266
2267#ifdef CONFIG_ATA_VERBOSE_ERROR
2268	if (ehc->i.serror)
2269		ata_link_err(link,
2270		  "SError: { %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s}\n",
2271		  ehc->i.serror & SERR_DATA_RECOVERED ? "RecovData " : "",
2272		  ehc->i.serror & SERR_COMM_RECOVERED ? "RecovComm " : "",
2273		  ehc->i.serror & SERR_DATA ? "UnrecovData " : "",
2274		  ehc->i.serror & SERR_PERSISTENT ? "Persist " : "",
2275		  ehc->i.serror & SERR_PROTOCOL ? "Proto " : "",
2276		  ehc->i.serror & SERR_INTERNAL ? "HostInt " : "",
2277		  ehc->i.serror & SERR_PHYRDY_CHG ? "PHYRdyChg " : "",
2278		  ehc->i.serror & SERR_PHY_INT_ERR ? "PHYInt " : "",
2279		  ehc->i.serror & SERR_COMM_WAKE ? "CommWake " : "",
2280		  ehc->i.serror & SERR_10B_8B_ERR ? "10B8B " : "",
2281		  ehc->i.serror & SERR_DISPARITY ? "Dispar " : "",
2282		  ehc->i.serror & SERR_CRC ? "BadCRC " : "",
2283		  ehc->i.serror & SERR_HANDSHAKE ? "Handshk " : "",
2284		  ehc->i.serror & SERR_LINK_SEQ_ERR ? "LinkSeq " : "",
2285		  ehc->i.serror & SERR_TRANS_ST_ERROR ? "TrStaTrns " : "",
2286		  ehc->i.serror & SERR_UNRECOG_FIS ? "UnrecFIS " : "",
2287		  ehc->i.serror & SERR_DEV_XCHG ? "DevExch " : "");
2288#endif
2289
2290	ata_qc_for_each_raw(ap, qc, tag) {
2291		struct ata_taskfile *cmd = &qc->tf, *res = &qc->result_tf;
2292		char data_buf[20] = "";
2293		char cdb_buf[70] = "";
2294
2295		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2296		    ata_dev_phys_link(qc->dev) != link || !qc->err_mask)
2297			continue;
2298
2299		if (qc->dma_dir != DMA_NONE) {
2300			static const char *dma_str[] = {
2301				[DMA_BIDIRECTIONAL]	= "bidi",
2302				[DMA_TO_DEVICE]		= "out",
2303				[DMA_FROM_DEVICE]	= "in",
2304			};
2305			const char *prot_str = NULL;
2306
2307			switch (qc->tf.protocol) {
2308			case ATA_PROT_UNKNOWN:
2309				prot_str = "unknown";
2310				break;
2311			case ATA_PROT_NODATA:
2312				prot_str = "nodata";
2313				break;
2314			case ATA_PROT_PIO:
2315				prot_str = "pio";
2316				break;
2317			case ATA_PROT_DMA:
2318				prot_str = "dma";
2319				break;
2320			case ATA_PROT_NCQ:
2321				prot_str = "ncq dma";
2322				break;
2323			case ATA_PROT_NCQ_NODATA:
2324				prot_str = "ncq nodata";
2325				break;
2326			case ATAPI_PROT_NODATA:
2327				prot_str = "nodata";
2328				break;
2329			case ATAPI_PROT_PIO:
2330				prot_str = "pio";
2331				break;
2332			case ATAPI_PROT_DMA:
2333				prot_str = "dma";
2334				break;
2335			}
2336			snprintf(data_buf, sizeof(data_buf), " %s %u %s",
2337				 prot_str, qc->nbytes, dma_str[qc->dma_dir]);
2338		}
2339
2340		if (ata_is_atapi(qc->tf.protocol)) {
2341			const u8 *cdb = qc->cdb;
2342			size_t cdb_len = qc->dev->cdb_len;
2343
2344			if (qc->scsicmd) {
2345				cdb = qc->scsicmd->cmnd;
2346				cdb_len = qc->scsicmd->cmd_len;
2347			}
2348			__scsi_format_command(cdb_buf, sizeof(cdb_buf),
2349					      cdb, cdb_len);
2350		} else {
2351			const char *descr = ata_get_cmd_descript(cmd->command);
2352			if (descr)
2353				ata_dev_err(qc->dev, "failed command: %s\n",
2354					    descr);
2355		}
2356
2357		ata_dev_err(qc->dev,
2358			"cmd %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2359			"tag %d%s\n         %s"
2360			"res %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2361			"Emask 0x%x (%s)%s\n",
2362			cmd->command, cmd->feature, cmd->nsect,
2363			cmd->lbal, cmd->lbam, cmd->lbah,
2364			cmd->hob_feature, cmd->hob_nsect,
2365			cmd->hob_lbal, cmd->hob_lbam, cmd->hob_lbah,
2366			cmd->device, qc->tag, data_buf, cdb_buf,
2367			res->command, res->feature, res->nsect,
2368			res->lbal, res->lbam, res->lbah,
2369			res->hob_feature, res->hob_nsect,
2370			res->hob_lbal, res->hob_lbam, res->hob_lbah,
2371			res->device, qc->err_mask, ata_err_string(qc->err_mask),
2372			qc->err_mask & AC_ERR_NCQ ? " <F>" : "");
2373
2374#ifdef CONFIG_ATA_VERBOSE_ERROR
2375		if (res->command & (ATA_BUSY | ATA_DRDY | ATA_DF | ATA_DRQ |
2376				    ATA_SENSE | ATA_ERR)) {
2377			if (res->command & ATA_BUSY)
2378				ata_dev_err(qc->dev, "status: { Busy }\n");
2379			else
2380				ata_dev_err(qc->dev, "status: { %s%s%s%s%s}\n",
2381				  res->command & ATA_DRDY ? "DRDY " : "",
2382				  res->command & ATA_DF ? "DF " : "",
2383				  res->command & ATA_DRQ ? "DRQ " : "",
2384				  res->command & ATA_SENSE ? "SENSE " : "",
2385				  res->command & ATA_ERR ? "ERR " : "");
2386		}
2387
2388		if (cmd->command != ATA_CMD_PACKET &&
2389		    (res->feature & (ATA_ICRC | ATA_UNC | ATA_AMNF |
2390				     ATA_IDNF | ATA_ABORTED)))
2391			ata_dev_err(qc->dev, "error: { %s%s%s%s%s}\n",
2392			  res->feature & ATA_ICRC ? "ICRC " : "",
2393			  res->feature & ATA_UNC ? "UNC " : "",
2394			  res->feature & ATA_AMNF ? "AMNF " : "",
2395			  res->feature & ATA_IDNF ? "IDNF " : "",
2396			  res->feature & ATA_ABORTED ? "ABRT " : "");
2397#endif
2398	}
2399}
2400
2401/**
2402 *	ata_eh_report - report error handling to user
2403 *	@ap: ATA port to report EH about
2404 *
2405 *	Report EH to user.
2406 *
2407 *	LOCKING:
2408 *	None.
2409 */
2410void ata_eh_report(struct ata_port *ap)
2411{
2412	struct ata_link *link;
2413
2414	ata_for_each_link(link, ap, HOST_FIRST)
2415		ata_eh_link_report(link);
2416}
2417
2418static int ata_do_reset(struct ata_link *link, ata_reset_fn_t reset,
2419			unsigned int *classes, unsigned long deadline,
2420			bool clear_classes)
2421{
2422	struct ata_device *dev;
2423
2424	if (clear_classes)
2425		ata_for_each_dev(dev, link, ALL)
2426			classes[dev->devno] = ATA_DEV_UNKNOWN;
2427
2428	return reset(link, classes, deadline);
2429}
2430
2431static int ata_eh_followup_srst_needed(struct ata_link *link, int rc)
2432{
2433	if ((link->flags & ATA_LFLAG_NO_SRST) || ata_link_offline(link))
2434		return 0;
2435	if (rc == -EAGAIN)
2436		return 1;
2437	if (sata_pmp_supported(link->ap) && ata_is_host_link(link))
2438		return 1;
2439	return 0;
2440}
2441
2442int ata_eh_reset(struct ata_link *link, int classify,
2443		 ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
2444		 ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
2445{
2446	struct ata_port *ap = link->ap;
2447	struct ata_link *slave = ap->slave_link;
2448	struct ata_eh_context *ehc = &link->eh_context;
2449	struct ata_eh_context *sehc = slave ? &slave->eh_context : NULL;
2450	unsigned int *classes = ehc->classes;
2451	unsigned int lflags = link->flags;
2452	int verbose = !(ehc->i.flags & ATA_EHI_QUIET);
2453	int max_tries = 0, try = 0;
2454	struct ata_link *failed_link;
2455	struct ata_device *dev;
2456	unsigned long deadline, now;
2457	ata_reset_fn_t reset;
2458	unsigned long flags;
2459	u32 sstatus;
2460	int nr_unknown, rc;
2461
2462	/*
2463	 * Prepare to reset
2464	 */
2465	while (ata_eh_reset_timeouts[max_tries] != ULONG_MAX)
2466		max_tries++;
2467	if (link->flags & ATA_LFLAG_RST_ONCE)
2468		max_tries = 1;
2469	if (link->flags & ATA_LFLAG_NO_HRST)
2470		hardreset = NULL;
2471	if (link->flags & ATA_LFLAG_NO_SRST)
2472		softreset = NULL;
2473
2474	/* make sure each reset attempt is at least COOL_DOWN apart */
2475	if (ehc->i.flags & ATA_EHI_DID_RESET) {
2476		now = jiffies;
2477		WARN_ON(time_after(ehc->last_reset, now));
2478		deadline = ata_deadline(ehc->last_reset,
2479					ATA_EH_RESET_COOL_DOWN);
2480		if (time_before(now, deadline))
2481			schedule_timeout_uninterruptible(deadline - now);
2482	}
2483
2484	spin_lock_irqsave(ap->lock, flags);
2485	ap->pflags |= ATA_PFLAG_RESETTING;
2486	spin_unlock_irqrestore(ap->lock, flags);
2487
2488	ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2489
2490	ata_for_each_dev(dev, link, ALL) {
2491		/* If we issue an SRST then an ATA drive (not ATAPI)
2492		 * may change configuration and be in PIO0 timing. If
2493		 * we do a hard reset (or are coming from power on)
2494		 * this is true for ATA or ATAPI. Until we've set a
2495		 * suitable controller mode we should not touch the
2496		 * bus as we may be talking too fast.
2497		 */
2498		dev->pio_mode = XFER_PIO_0;
2499		dev->dma_mode = 0xff;
2500
2501		/* If the controller has a pio mode setup function
2502		 * then use it to set the chipset to rights. Don't
2503		 * touch the DMA setup as that will be dealt with when
2504		 * configuring devices.
2505		 */
2506		if (ap->ops->set_piomode)
2507			ap->ops->set_piomode(ap, dev);
2508	}
2509
2510	/* prefer hardreset */
2511	reset = NULL;
2512	ehc->i.action &= ~ATA_EH_RESET;
2513	if (hardreset) {
2514		reset = hardreset;
2515		ehc->i.action |= ATA_EH_HARDRESET;
2516	} else if (softreset) {
2517		reset = softreset;
2518		ehc->i.action |= ATA_EH_SOFTRESET;
2519	}
2520
2521	if (prereset) {
2522		unsigned long deadline = ata_deadline(jiffies,
2523						      ATA_EH_PRERESET_TIMEOUT);
2524
2525		if (slave) {
2526			sehc->i.action &= ~ATA_EH_RESET;
2527			sehc->i.action |= ehc->i.action;
2528		}
2529
2530		rc = prereset(link, deadline);
2531
2532		/* If present, do prereset on slave link too.  Reset
2533		 * is skipped iff both master and slave links report
2534		 * -ENOENT or clear ATA_EH_RESET.
2535		 */
2536		if (slave && (rc == 0 || rc == -ENOENT)) {
2537			int tmp;
2538
2539			tmp = prereset(slave, deadline);
2540			if (tmp != -ENOENT)
2541				rc = tmp;
2542
2543			ehc->i.action |= sehc->i.action;
2544		}
2545
2546		if (rc) {
2547			if (rc == -ENOENT) {
2548				ata_link_dbg(link, "port disabled--ignoring\n");
2549				ehc->i.action &= ~ATA_EH_RESET;
2550
2551				ata_for_each_dev(dev, link, ALL)
2552					classes[dev->devno] = ATA_DEV_NONE;
2553
2554				rc = 0;
2555			} else
2556				ata_link_err(link,
2557					     "prereset failed (errno=%d)\n",
2558					     rc);
2559			goto out;
2560		}
2561
2562		/* prereset() might have cleared ATA_EH_RESET.  If so,
2563		 * bang classes, thaw and return.
2564		 */
2565		if (reset && !(ehc->i.action & ATA_EH_RESET)) {
2566			ata_for_each_dev(dev, link, ALL)
2567				classes[dev->devno] = ATA_DEV_NONE;
2568			if ((ap->pflags & ATA_PFLAG_FROZEN) &&
2569			    ata_is_host_link(link))
2570				ata_eh_thaw_port(ap);
2571			rc = 0;
2572			goto out;
2573		}
2574	}
2575
2576 retry:
2577	/*
2578	 * Perform reset
2579	 */
2580	if (ata_is_host_link(link))
2581		ata_eh_freeze_port(ap);
2582
2583	deadline = ata_deadline(jiffies, ata_eh_reset_timeouts[try++]);
2584
2585	if (reset) {
2586		if (verbose)
2587			ata_link_info(link, "%s resetting link\n",
2588				      reset == softreset ? "soft" : "hard");
2589
2590		/* mark that this EH session started with reset */
2591		ehc->last_reset = jiffies;
2592		if (reset == hardreset)
2593			ehc->i.flags |= ATA_EHI_DID_HARDRESET;
2594		else
2595			ehc->i.flags |= ATA_EHI_DID_SOFTRESET;
2596
2597		rc = ata_do_reset(link, reset, classes, deadline, true);
2598		if (rc && rc != -EAGAIN) {
2599			failed_link = link;
2600			goto fail;
2601		}
2602
2603		/* hardreset slave link if existent */
2604		if (slave && reset == hardreset) {
2605			int tmp;
2606
2607			if (verbose)
2608				ata_link_info(slave, "hard resetting link\n");
2609
2610			ata_eh_about_to_do(slave, NULL, ATA_EH_RESET);
2611			tmp = ata_do_reset(slave, reset, classes, deadline,
2612					   false);
2613			switch (tmp) {
2614			case -EAGAIN:
2615				rc = -EAGAIN;
2616				break;
2617			case 0:
2618				break;
2619			default:
2620				failed_link = slave;
2621				rc = tmp;
2622				goto fail;
2623			}
2624		}
2625
2626		/* perform follow-up SRST if necessary */
2627		if (reset == hardreset &&
2628		    ata_eh_followup_srst_needed(link, rc)) {
2629			reset = softreset;
2630
2631			if (!reset) {
2632				ata_link_err(link,
2633	     "follow-up softreset required but no softreset available\n");
2634				failed_link = link;
2635				rc = -EINVAL;
2636				goto fail;
2637			}
2638
2639			ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2640			rc = ata_do_reset(link, reset, classes, deadline, true);
2641			if (rc) {
2642				failed_link = link;
2643				goto fail;
2644			}
2645		}
2646	} else {
2647		if (verbose)
2648			ata_link_info(link,
2649	"no reset method available, skipping reset\n");
2650		if (!(lflags & ATA_LFLAG_ASSUME_CLASS))
2651			lflags |= ATA_LFLAG_ASSUME_ATA;
2652	}
2653
2654	/*
2655	 * Post-reset processing
2656	 */
2657	ata_for_each_dev(dev, link, ALL) {
2658		/* After the reset, the device state is PIO 0 and the
2659		 * controller state is undefined.  Reset also wakes up
2660		 * drives from sleeping mode.
2661		 */
2662		dev->pio_mode = XFER_PIO_0;
2663		dev->flags &= ~ATA_DFLAG_SLEEPING;
2664
2665		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
2666			continue;
2667
2668		/* apply class override */
2669		if (lflags & ATA_LFLAG_ASSUME_ATA)
2670			classes[dev->devno] = ATA_DEV_ATA;
2671		else if (lflags & ATA_LFLAG_ASSUME_SEMB)
2672			classes[dev->devno] = ATA_DEV_SEMB_UNSUP;
2673	}
2674
2675	/* record current link speed */
2676	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0)
2677		link->sata_spd = (sstatus >> 4) & 0xf;
2678	if (slave && sata_scr_read(slave, SCR_STATUS, &sstatus) == 0)
2679		slave->sata_spd = (sstatus >> 4) & 0xf;
2680
2681	/* thaw the port */
2682	if (ata_is_host_link(link))
2683		ata_eh_thaw_port(ap);
2684
2685	/* postreset() should clear hardware SError.  Although SError
2686	 * is cleared during link resume, clearing SError here is
2687	 * necessary as some PHYs raise hotplug events after SRST.
2688	 * This introduces race condition where hotplug occurs between
2689	 * reset and here.  This race is mediated by cross checking
2690	 * link onlineness and classification result later.
2691	 */
2692	if (postreset) {
2693		postreset(link, classes);
2694		if (slave)
2695			postreset(slave, classes);
2696	}
2697
2698	/*
2699	 * Some controllers can't be frozen very well and may set spurious
2700	 * error conditions during reset.  Clear accumulated error
2701	 * information and re-thaw the port if frozen.  As reset is the
2702	 * final recovery action and we cross check link onlineness against
2703	 * device classification later, no hotplug event is lost by this.
2704	 */
2705	spin_lock_irqsave(link->ap->lock, flags);
2706	memset(&link->eh_info, 0, sizeof(link->eh_info));
2707	if (slave)
2708		memset(&slave->eh_info, 0, sizeof(link->eh_info));
2709	ap->pflags &= ~ATA_PFLAG_EH_PENDING;
2710	spin_unlock_irqrestore(link->ap->lock, flags);
2711
2712	if (ap->pflags & ATA_PFLAG_FROZEN)
2713		ata_eh_thaw_port(ap);
2714
2715	/*
2716	 * Make sure onlineness and classification result correspond.
2717	 * Hotplug could have happened during reset and some
2718	 * controllers fail to wait while a drive is spinning up after
2719	 * being hotplugged causing misdetection.  By cross checking
2720	 * link on/offlineness and classification result, those
2721	 * conditions can be reliably detected and retried.
2722	 */
2723	nr_unknown = 0;
2724	ata_for_each_dev(dev, link, ALL) {
2725		if (ata_phys_link_online(ata_dev_phys_link(dev))) {
2726			if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2727				ata_dev_dbg(dev, "link online but device misclassified\n");
2728				classes[dev->devno] = ATA_DEV_NONE;
2729				nr_unknown++;
2730			}
2731		} else if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
2732			if (ata_class_enabled(classes[dev->devno]))
2733				ata_dev_dbg(dev,
2734					    "link offline, clearing class %d to NONE\n",
2735					    classes[dev->devno]);
2736			classes[dev->devno] = ATA_DEV_NONE;
2737		} else if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2738			ata_dev_dbg(dev,
2739				    "link status unknown, clearing UNKNOWN to NONE\n");
2740			classes[dev->devno] = ATA_DEV_NONE;
2741		}
2742	}
2743
2744	if (classify && nr_unknown) {
2745		if (try < max_tries) {
2746			ata_link_warn(link,
2747				      "link online but %d devices misclassified, retrying\n",
2748				      nr_unknown);
2749			failed_link = link;
2750			rc = -EAGAIN;
2751			goto fail;
2752		}
2753		ata_link_warn(link,
2754			      "link online but %d devices misclassified, "
2755			      "device detection might fail\n", nr_unknown);
2756	}
2757
2758	/* reset successful, schedule revalidation */
2759	ata_eh_done(link, NULL, ATA_EH_RESET);
2760	if (slave)
2761		ata_eh_done(slave, NULL, ATA_EH_RESET);
2762	ehc->last_reset = jiffies;		/* update to completion time */
2763	ehc->i.action |= ATA_EH_REVALIDATE;
2764	link->lpm_policy = ATA_LPM_UNKNOWN;	/* reset LPM state */
2765
2766	rc = 0;
2767 out:
2768	/* clear hotplug flag */
2769	ehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2770	if (slave)
2771		sehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2772
2773	spin_lock_irqsave(ap->lock, flags);
2774	ap->pflags &= ~ATA_PFLAG_RESETTING;
2775	spin_unlock_irqrestore(ap->lock, flags);
2776
2777	return rc;
2778
2779 fail:
2780	/* if SCR isn't accessible on a fan-out port, PMP needs to be reset */
2781	if (!ata_is_host_link(link) &&
2782	    sata_scr_read(link, SCR_STATUS, &sstatus))
2783		rc = -ERESTART;
2784
2785	if (try >= max_tries) {
2786		/*
2787		 * Thaw host port even if reset failed, so that the port
2788		 * can be retried on the next phy event.  This risks
2789		 * repeated EH runs but seems to be a better tradeoff than
2790		 * shutting down a port after a botched hotplug attempt.
2791		 */
2792		if (ata_is_host_link(link))
2793			ata_eh_thaw_port(ap);
2794		goto out;
2795	}
2796
2797	now = jiffies;
2798	if (time_before(now, deadline)) {
2799		unsigned long delta = deadline - now;
2800
2801		ata_link_warn(failed_link,
2802			"reset failed (errno=%d), retrying in %u secs\n",
2803			rc, DIV_ROUND_UP(jiffies_to_msecs(delta), 1000));
2804
2805		ata_eh_release(ap);
2806		while (delta)
2807			delta = schedule_timeout_uninterruptible(delta);
2808		ata_eh_acquire(ap);
2809	}
2810
2811	/*
2812	 * While disks spinup behind PMP, some controllers fail sending SRST.
2813	 * They need to be reset - as well as the PMP - before retrying.
2814	 */
2815	if (rc == -ERESTART) {
2816		if (ata_is_host_link(link))
2817			ata_eh_thaw_port(ap);
2818		goto out;
2819	}
2820
2821	if (try == max_tries - 1) {
2822		sata_down_spd_limit(link, 0);
2823		if (slave)
2824			sata_down_spd_limit(slave, 0);
2825	} else if (rc == -EPIPE)
2826		sata_down_spd_limit(failed_link, 0);
2827
2828	if (hardreset)
2829		reset = hardreset;
2830	goto retry;
2831}
2832
2833static inline void ata_eh_pull_park_action(struct ata_port *ap)
2834{
2835	struct ata_link *link;
2836	struct ata_device *dev;
2837	unsigned long flags;
2838
2839	/*
2840	 * This function can be thought of as an extended version of
2841	 * ata_eh_about_to_do() specially crafted to accommodate the
2842	 * requirements of ATA_EH_PARK handling. Since the EH thread
2843	 * does not leave the do {} while () loop in ata_eh_recover as
2844	 * long as the timeout for a park request to *one* device on
2845	 * the port has not expired, and since we still want to pick
2846	 * up park requests to other devices on the same port or
2847	 * timeout updates for the same device, we have to pull
2848	 * ATA_EH_PARK actions from eh_info into eh_context.i
2849	 * ourselves at the beginning of each pass over the loop.
2850	 *
2851	 * Additionally, all write accesses to &ap->park_req_pending
2852	 * through reinit_completion() (see below) or complete_all()
2853	 * (see ata_scsi_park_store()) are protected by the host lock.
2854	 * As a result we have that park_req_pending.done is zero on
2855	 * exit from this function, i.e. when ATA_EH_PARK actions for
2856	 * *all* devices on port ap have been pulled into the
2857	 * respective eh_context structs. If, and only if,
2858	 * park_req_pending.done is non-zero by the time we reach
2859	 * wait_for_completion_timeout(), another ATA_EH_PARK action
2860	 * has been scheduled for at least one of the devices on port
2861	 * ap and we have to cycle over the do {} while () loop in
2862	 * ata_eh_recover() again.
2863	 */
2864
2865	spin_lock_irqsave(ap->lock, flags);
2866	reinit_completion(&ap->park_req_pending);
2867	ata_for_each_link(link, ap, EDGE) {
2868		ata_for_each_dev(dev, link, ALL) {
2869			struct ata_eh_info *ehi = &link->eh_info;
2870
2871			link->eh_context.i.dev_action[dev->devno] |=
2872				ehi->dev_action[dev->devno] & ATA_EH_PARK;
2873			ata_eh_clear_action(link, dev, ehi, ATA_EH_PARK);
2874		}
2875	}
2876	spin_unlock_irqrestore(ap->lock, flags);
2877}
2878
2879static void ata_eh_park_issue_cmd(struct ata_device *dev, int park)
2880{
2881	struct ata_eh_context *ehc = &dev->link->eh_context;
2882	struct ata_taskfile tf;
2883	unsigned int err_mask;
2884
2885	ata_tf_init(dev, &tf);
2886	if (park) {
2887		ehc->unloaded_mask |= 1 << dev->devno;
2888		tf.command = ATA_CMD_IDLEIMMEDIATE;
2889		tf.feature = 0x44;
2890		tf.lbal = 0x4c;
2891		tf.lbam = 0x4e;
2892		tf.lbah = 0x55;
2893	} else {
2894		ehc->unloaded_mask &= ~(1 << dev->devno);
2895		tf.command = ATA_CMD_CHK_POWER;
2896	}
2897
2898	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
2899	tf.protocol = ATA_PROT_NODATA;
2900	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
2901	if (park && (err_mask || tf.lbal != 0xc4)) {
2902		ata_dev_err(dev, "head unload failed!\n");
2903		ehc->unloaded_mask &= ~(1 << dev->devno);
2904	}
2905}
2906
2907static int ata_eh_revalidate_and_attach(struct ata_link *link,
2908					struct ata_device **r_failed_dev)
2909{
2910	struct ata_port *ap = link->ap;
2911	struct ata_eh_context *ehc = &link->eh_context;
2912	struct ata_device *dev;
2913	unsigned int new_mask = 0;
2914	unsigned long flags;
2915	int rc = 0;
2916
2917	DPRINTK("ENTER\n");
2918
2919	/* For PATA drive side cable detection to work, IDENTIFY must
2920	 * be done backwards such that PDIAG- is released by the slave
2921	 * device before the master device is identified.
2922	 */
2923	ata_for_each_dev(dev, link, ALL_REVERSE) {
2924		unsigned int action = ata_eh_dev_action(dev);
2925		unsigned int readid_flags = 0;
2926
2927		if (ehc->i.flags & ATA_EHI_DID_RESET)
2928			readid_flags |= ATA_READID_POSTRESET;
2929
2930		if ((action & ATA_EH_REVALIDATE) && ata_dev_enabled(dev)) {
2931			WARN_ON(dev->class == ATA_DEV_PMP);
2932
2933			if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
2934				rc = -EIO;
2935				goto err;
2936			}
2937
2938			ata_eh_about_to_do(link, dev, ATA_EH_REVALIDATE);
2939			rc = ata_dev_revalidate(dev, ehc->classes[dev->devno],
2940						readid_flags);
2941			if (rc)
2942				goto err;
2943
2944			ata_eh_done(link, dev, ATA_EH_REVALIDATE);
2945
2946			/* Configuration may have changed, reconfigure
2947			 * transfer mode.
2948			 */
2949			ehc->i.flags |= ATA_EHI_SETMODE;
2950
2951			/* schedule the scsi_rescan_device() here */
2952			schedule_work(&(ap->scsi_rescan_task));
2953		} else if (dev->class == ATA_DEV_UNKNOWN &&
2954			   ehc->tries[dev->devno] &&
2955			   ata_class_enabled(ehc->classes[dev->devno])) {
2956			/* Temporarily set dev->class, it will be
2957			 * permanently set once all configurations are
2958			 * complete.  This is necessary because new
2959			 * device configuration is done in two
2960			 * separate loops.
2961			 */
2962			dev->class = ehc->classes[dev->devno];
2963
2964			if (dev->class == ATA_DEV_PMP)
2965				rc = sata_pmp_attach(dev);
2966			else
2967				rc = ata_dev_read_id(dev, &dev->class,
2968						     readid_flags, dev->id);
2969
2970			/* read_id might have changed class, store and reset */
2971			ehc->classes[dev->devno] = dev->class;
2972			dev->class = ATA_DEV_UNKNOWN;
2973
2974			switch (rc) {
2975			case 0:
2976				/* clear error info accumulated during probe */
2977				ata_ering_clear(&dev->ering);
2978				new_mask |= 1 << dev->devno;
2979				break;
2980			case -ENOENT:
2981				/* IDENTIFY was issued to non-existent
2982				 * device.  No need to reset.  Just
2983				 * thaw and ignore the device.
2984				 */
2985				ata_eh_thaw_port(ap);
2986				break;
2987			default:
2988				goto err;
2989			}
2990		}
2991	}
2992
2993	/* PDIAG- should have been released, ask cable type if post-reset */
2994	if ((ehc->i.flags & ATA_EHI_DID_RESET) && ata_is_host_link(link)) {
2995		if (ap->ops->cable_detect)
2996			ap->cbl = ap->ops->cable_detect(ap);
2997		ata_force_cbl(ap);
2998	}
2999
3000	/* Configure new devices forward such that user doesn't see
3001	 * device detection messages backwards.
3002	 */
3003	ata_for_each_dev(dev, link, ALL) {
3004		if (!(new_mask & (1 << dev->devno)))
3005			continue;
3006
3007		dev->class = ehc->classes[dev->devno];
3008
3009		if (dev->class == ATA_DEV_PMP)
3010			continue;
3011
3012		ehc->i.flags |= ATA_EHI_PRINTINFO;
3013		rc = ata_dev_configure(dev);
3014		ehc->i.flags &= ~ATA_EHI_PRINTINFO;
3015		if (rc) {
3016			dev->class = ATA_DEV_UNKNOWN;
3017			goto err;
3018		}
3019
3020		spin_lock_irqsave(ap->lock, flags);
3021		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
3022		spin_unlock_irqrestore(ap->lock, flags);
3023
3024		/* new device discovered, configure xfermode */
3025		ehc->i.flags |= ATA_EHI_SETMODE;
3026	}
3027
3028	return 0;
3029
3030 err:
3031	*r_failed_dev = dev;
3032	DPRINTK("EXIT rc=%d\n", rc);
3033	return rc;
3034}
3035
3036/**
3037 *	ata_set_mode - Program timings and issue SET FEATURES - XFER
3038 *	@link: link on which timings will be programmed
3039 *	@r_failed_dev: out parameter for failed device
3040 *
3041 *	Set ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3042 *	ata_set_mode() fails, pointer to the failing device is
3043 *	returned in @r_failed_dev.
3044 *
3045 *	LOCKING:
3046 *	PCI/etc. bus probe sem.
3047 *
3048 *	RETURNS:
3049 *	0 on success, negative errno otherwise
3050 */
3051int ata_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3052{
3053	struct ata_port *ap = link->ap;
3054	struct ata_device *dev;
3055	int rc;
3056
3057	/* if data transfer is verified, clear DUBIOUS_XFER on ering top */
3058	ata_for_each_dev(dev, link, ENABLED) {
3059		if (!(dev->flags & ATA_DFLAG_DUBIOUS_XFER)) {
3060			struct ata_ering_entry *ent;
3061
3062			ent = ata_ering_top(&dev->ering);
3063			if (ent)
3064				ent->eflags &= ~ATA_EFLAG_DUBIOUS_XFER;
3065		}
3066	}
3067
3068	/* has private set_mode? */
3069	if (ap->ops->set_mode)
3070		rc = ap->ops->set_mode(link, r_failed_dev);
3071	else
3072		rc = ata_do_set_mode(link, r_failed_dev);
3073
3074	/* if transfer mode has changed, set DUBIOUS_XFER on device */
3075	ata_for_each_dev(dev, link, ENABLED) {
3076		struct ata_eh_context *ehc = &link->eh_context;
3077		u8 saved_xfer_mode = ehc->saved_xfer_mode[dev->devno];
3078		u8 saved_ncq = !!(ehc->saved_ncq_enabled & (1 << dev->devno));
3079
3080		if (dev->xfer_mode != saved_xfer_mode ||
3081		    ata_ncq_enabled(dev) != saved_ncq)
3082			dev->flags |= ATA_DFLAG_DUBIOUS_XFER;
3083	}
3084
3085	return rc;
3086}
3087
3088/**
3089 *	atapi_eh_clear_ua - Clear ATAPI UNIT ATTENTION after reset
3090 *	@dev: ATAPI device to clear UA for
3091 *
3092 *	Resets and other operations can make an ATAPI device raise
3093 *	UNIT ATTENTION which causes the next operation to fail.  This
3094 *	function clears UA.
3095 *
3096 *	LOCKING:
3097 *	EH context (may sleep).
3098 *
3099 *	RETURNS:
3100 *	0 on success, -errno on failure.
3101 */
3102static int atapi_eh_clear_ua(struct ata_device *dev)
3103{
3104	int i;
3105
3106	for (i = 0; i < ATA_EH_UA_TRIES; i++) {
3107		u8 *sense_buffer = dev->link->ap->sector_buf;
3108		u8 sense_key = 0;
3109		unsigned int err_mask;
3110
3111		err_mask = atapi_eh_tur(dev, &sense_key);
3112		if (err_mask != 0 && err_mask != AC_ERR_DEV) {
3113			ata_dev_warn(dev,
3114				     "TEST_UNIT_READY failed (err_mask=0x%x)\n",
3115				     err_mask);
3116			return -EIO;
3117		}
3118
3119		if (!err_mask || sense_key != UNIT_ATTENTION)
3120			return 0;
3121
3122		err_mask = atapi_eh_request_sense(dev, sense_buffer, sense_key);
3123		if (err_mask) {
3124			ata_dev_warn(dev, "failed to clear "
3125				"UNIT ATTENTION (err_mask=0x%x)\n", err_mask);
3126			return -EIO;
3127		}
3128	}
3129
3130	ata_dev_warn(dev, "UNIT ATTENTION persists after %d tries\n",
3131		     ATA_EH_UA_TRIES);
3132
3133	return 0;
3134}
3135
3136/**
3137 *	ata_eh_maybe_retry_flush - Retry FLUSH if necessary
3138 *	@dev: ATA device which may need FLUSH retry
3139 *
3140 *	If @dev failed FLUSH, it needs to be reported upper layer
3141 *	immediately as it means that @dev failed to remap and already
3142 *	lost at least a sector and further FLUSH retrials won't make
3143 *	any difference to the lost sector.  However, if FLUSH failed
3144 *	for other reasons, for example transmission error, FLUSH needs
3145 *	to be retried.
3146 *
3147 *	This function determines whether FLUSH failure retry is
3148 *	necessary and performs it if so.
3149 *
3150 *	RETURNS:
3151 *	0 if EH can continue, -errno if EH needs to be repeated.
3152 */
3153static int ata_eh_maybe_retry_flush(struct ata_device *dev)
3154{
3155	struct ata_link *link = dev->link;
3156	struct ata_port *ap = link->ap;
3157	struct ata_queued_cmd *qc;
3158	struct ata_taskfile tf;
3159	unsigned int err_mask;
3160	int rc = 0;
3161
3162	/* did flush fail for this device? */
3163	if (!ata_tag_valid(link->active_tag))
3164		return 0;
3165
3166	qc = __ata_qc_from_tag(ap, link->active_tag);
3167	if (qc->dev != dev || (qc->tf.command != ATA_CMD_FLUSH_EXT &&
3168			       qc->tf.command != ATA_CMD_FLUSH))
3169		return 0;
3170
3171	/* if the device failed it, it should be reported to upper layers */
3172	if (qc->err_mask & AC_ERR_DEV)
3173		return 0;
3174
3175	/* flush failed for some other reason, give it another shot */
3176	ata_tf_init(dev, &tf);
3177
3178	tf.command = qc->tf.command;
3179	tf.flags |= ATA_TFLAG_DEVICE;
3180	tf.protocol = ATA_PROT_NODATA;
3181
3182	ata_dev_warn(dev, "retrying FLUSH 0x%x Emask 0x%x\n",
3183		       tf.command, qc->err_mask);
3184
3185	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
3186	if (!err_mask) {
3187		/*
3188		 * FLUSH is complete but there's no way to
3189		 * successfully complete a failed command from EH.
3190		 * Making sure retry is allowed at least once and
3191		 * retrying it should do the trick - whatever was in
3192		 * the cache is already on the platter and this won't
3193		 * cause infinite loop.
3194		 */
3195		qc->scsicmd->allowed = max(qc->scsicmd->allowed, 1);
3196	} else {
3197		ata_dev_warn(dev, "FLUSH failed Emask 0x%x\n",
3198			       err_mask);
3199		rc = -EIO;
3200
3201		/* if device failed it, report it to upper layers */
3202		if (err_mask & AC_ERR_DEV) {
3203			qc->err_mask |= AC_ERR_DEV;
3204			qc->result_tf = tf;
3205			if (!(ap->pflags & ATA_PFLAG_FROZEN))
3206				rc = 0;
3207		}
3208	}
3209	return rc;
3210}
3211
3212/**
3213 *	ata_eh_set_lpm - configure SATA interface power management
3214 *	@link: link to configure power management
3215 *	@policy: the link power management policy
3216 *	@r_failed_dev: out parameter for failed device
3217 *
3218 *	Enable SATA Interface power management.  This will enable
3219 *	Device Interface Power Management (DIPM) for min_power and
3220 *	medium_power_with_dipm policies, and then call driver specific
3221 *	callbacks for enabling Host Initiated Power management.
3222 *
3223 *	LOCKING:
3224 *	EH context.
3225 *
3226 *	RETURNS:
3227 *	0 on success, -errno on failure.
3228 */
3229static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
3230			  struct ata_device **r_failed_dev)
3231{
3232	struct ata_port *ap = ata_is_host_link(link) ? link->ap : NULL;
3233	struct ata_eh_context *ehc = &link->eh_context;
3234	struct ata_device *dev, *link_dev = NULL, *lpm_dev = NULL;
3235	enum ata_lpm_policy old_policy = link->lpm_policy;
3236	bool no_dipm = link->ap->flags & ATA_FLAG_NO_DIPM;
3237	unsigned int hints = ATA_LPM_EMPTY | ATA_LPM_HIPM;
3238	unsigned int err_mask;
3239	int rc;
3240
3241	/* if the link or host doesn't do LPM, noop */
3242	if (!IS_ENABLED(CONFIG_SATA_HOST) ||
3243	    (link->flags & ATA_LFLAG_NO_LPM) || (ap && !ap->ops->set_lpm))
3244		return 0;
3245
3246	/*
3247	 * DIPM is enabled only for MIN_POWER as some devices
3248	 * misbehave when the host NACKs transition to SLUMBER.  Order
3249	 * device and link configurations such that the host always
3250	 * allows DIPM requests.
3251	 */
3252	ata_for_each_dev(dev, link, ENABLED) {
3253		bool hipm = ata_id_has_hipm(dev->id);
3254		bool dipm = ata_id_has_dipm(dev->id) && !no_dipm;
3255
3256		/* find the first enabled and LPM enabled devices */
3257		if (!link_dev)
3258			link_dev = dev;
3259
3260		if (!lpm_dev && (hipm || dipm))
3261			lpm_dev = dev;
3262
3263		hints &= ~ATA_LPM_EMPTY;
3264		if (!hipm)
3265			hints &= ~ATA_LPM_HIPM;
3266
3267		/* disable DIPM before changing link config */
3268		if (policy < ATA_LPM_MED_POWER_WITH_DIPM && dipm) {
3269			err_mask = ata_dev_set_feature(dev,
3270					SETFEATURES_SATA_DISABLE, SATA_DIPM);
3271			if (err_mask && err_mask != AC_ERR_DEV) {
3272				ata_dev_warn(dev,
3273					     "failed to disable DIPM, Emask 0x%x\n",
3274					     err_mask);
3275				rc = -EIO;
3276				goto fail;
3277			}
3278		}
3279	}
3280
3281	if (ap) {
3282		rc = ap->ops->set_lpm(link, policy, hints);
3283		if (!rc && ap->slave_link)
3284			rc = ap->ops->set_lpm(ap->slave_link, policy, hints);
3285	} else
3286		rc = sata_pmp_set_lpm(link, policy, hints);
3287
3288	/*
3289	 * Attribute link config failure to the first (LPM) enabled
3290	 * device on the link.
3291	 */
3292	if (rc) {
3293		if (rc == -EOPNOTSUPP) {
3294			link->flags |= ATA_LFLAG_NO_LPM;
3295			return 0;
3296		}
3297		dev = lpm_dev ? lpm_dev : link_dev;
3298		goto fail;
3299	}
3300
3301	/*
3302	 * Low level driver acked the transition.  Issue DIPM command
3303	 * with the new policy set.
3304	 */
3305	link->lpm_policy = policy;
3306	if (ap && ap->slave_link)
3307		ap->slave_link->lpm_policy = policy;
3308
3309	/* host config updated, enable DIPM if transitioning to MIN_POWER */
3310	ata_for_each_dev(dev, link, ENABLED) {
3311		if (policy >= ATA_LPM_MED_POWER_WITH_DIPM && !no_dipm &&
3312		    ata_id_has_dipm(dev->id)) {
3313			err_mask = ata_dev_set_feature(dev,
3314					SETFEATURES_SATA_ENABLE, SATA_DIPM);
3315			if (err_mask && err_mask != AC_ERR_DEV) {
3316				ata_dev_warn(dev,
3317					"failed to enable DIPM, Emask 0x%x\n",
3318					err_mask);
3319				rc = -EIO;
3320				goto fail;
3321			}
3322		}
3323	}
3324
3325	link->last_lpm_change = jiffies;
3326	link->flags |= ATA_LFLAG_CHANGED;
3327
3328	return 0;
3329
3330fail:
3331	/* restore the old policy */
3332	link->lpm_policy = old_policy;
3333	if (ap && ap->slave_link)
3334		ap->slave_link->lpm_policy = old_policy;
3335
3336	/* if no device or only one more chance is left, disable LPM */
3337	if (!dev || ehc->tries[dev->devno] <= 2) {
3338		ata_link_warn(link, "disabling LPM on the link\n");
3339		link->flags |= ATA_LFLAG_NO_LPM;
3340	}
3341	if (r_failed_dev)
3342		*r_failed_dev = dev;
3343	return rc;
3344}
3345
3346int ata_link_nr_enabled(struct ata_link *link)
3347{
3348	struct ata_device *dev;
3349	int cnt = 0;
3350
3351	ata_for_each_dev(dev, link, ENABLED)
3352		cnt++;
3353	return cnt;
3354}
3355
3356static int ata_link_nr_vacant(struct ata_link *link)
3357{
3358	struct ata_device *dev;
3359	int cnt = 0;
3360
3361	ata_for_each_dev(dev, link, ALL)
3362		if (dev->class == ATA_DEV_UNKNOWN)
3363			cnt++;
3364	return cnt;
3365}
3366
3367static int ata_eh_skip_recovery(struct ata_link *link)
3368{
3369	struct ata_port *ap = link->ap;
3370	struct ata_eh_context *ehc = &link->eh_context;
3371	struct ata_device *dev;
3372
3373	/* skip disabled links */
3374	if (link->flags & ATA_LFLAG_DISABLED)
3375		return 1;
3376
3377	/* skip if explicitly requested */
3378	if (ehc->i.flags & ATA_EHI_NO_RECOVERY)
3379		return 1;
3380
3381	/* thaw frozen port and recover failed devices */
3382	if ((ap->pflags & ATA_PFLAG_FROZEN) || ata_link_nr_enabled(link))
3383		return 0;
3384
3385	/* reset at least once if reset is requested */
3386	if ((ehc->i.action & ATA_EH_RESET) &&
3387	    !(ehc->i.flags & ATA_EHI_DID_RESET))
3388		return 0;
3389
3390	/* skip if class codes for all vacant slots are ATA_DEV_NONE */
3391	ata_for_each_dev(dev, link, ALL) {
3392		if (dev->class == ATA_DEV_UNKNOWN &&
3393		    ehc->classes[dev->devno] != ATA_DEV_NONE)
3394			return 0;
3395	}
3396
3397	return 1;
3398}
3399
3400static int ata_count_probe_trials_cb(struct ata_ering_entry *ent, void *void_arg)
3401{
3402	u64 interval = msecs_to_jiffies(ATA_EH_PROBE_TRIAL_INTERVAL);
3403	u64 now = get_jiffies_64();
3404	int *trials = void_arg;
3405
3406	if ((ent->eflags & ATA_EFLAG_OLD_ER) ||
3407	    (ent->timestamp < now - min(now, interval)))
3408		return -1;
3409
3410	(*trials)++;
3411	return 0;
3412}
3413
3414static int ata_eh_schedule_probe(struct ata_device *dev)
3415{
3416	struct ata_eh_context *ehc = &dev->link->eh_context;
3417	struct ata_link *link = ata_dev_phys_link(dev);
3418	int trials = 0;
3419
3420	if (!(ehc->i.probe_mask & (1 << dev->devno)) ||
3421	    (ehc->did_probe_mask & (1 << dev->devno)))
3422		return 0;
3423
3424	ata_eh_detach_dev(dev);
3425	ata_dev_init(dev);
3426	ehc->did_probe_mask |= (1 << dev->devno);
3427	ehc->i.action |= ATA_EH_RESET;
3428	ehc->saved_xfer_mode[dev->devno] = 0;
3429	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
3430
3431	/* the link maybe in a deep sleep, wake it up */
3432	if (link->lpm_policy > ATA_LPM_MAX_POWER) {
3433		if (ata_is_host_link(link))
3434			link->ap->ops->set_lpm(link, ATA_LPM_MAX_POWER,
3435					       ATA_LPM_EMPTY);
3436		else
3437			sata_pmp_set_lpm(link, ATA_LPM_MAX_POWER,
3438					 ATA_LPM_EMPTY);
3439	}
3440
3441	/* Record and count probe trials on the ering.  The specific
3442	 * error mask used is irrelevant.  Because a successful device
3443	 * detection clears the ering, this count accumulates only if
3444	 * there are consecutive failed probes.
3445	 *
3446	 * If the count is equal to or higher than ATA_EH_PROBE_TRIALS
3447	 * in the last ATA_EH_PROBE_TRIAL_INTERVAL, link speed is
3448	 * forced to 1.5Gbps.
3449	 *
3450	 * This is to work around cases where failed link speed
3451	 * negotiation results in device misdetection leading to
3452	 * infinite DEVXCHG or PHRDY CHG events.
3453	 */
3454	ata_ering_record(&dev->ering, 0, AC_ERR_OTHER);
3455	ata_ering_map(&dev->ering, ata_count_probe_trials_cb, &trials);
3456
3457	if (trials > ATA_EH_PROBE_TRIALS)
3458		sata_down_spd_limit(link, 1);
3459
3460	return 1;
3461}
3462
3463static int ata_eh_handle_dev_fail(struct ata_device *dev, int err)
3464{
3465	struct ata_eh_context *ehc = &dev->link->eh_context;
3466
3467	/* -EAGAIN from EH routine indicates retry without prejudice.
3468	 * The requester is responsible for ensuring forward progress.
3469	 */
3470	if (err != -EAGAIN)
3471		ehc->tries[dev->devno]--;
3472
3473	switch (err) {
3474	case -ENODEV:
3475		/* device missing or wrong IDENTIFY data, schedule probing */
3476		ehc->i.probe_mask |= (1 << dev->devno);
3477		fallthrough;
3478	case -EINVAL:
3479		/* give it just one more chance */
3480		ehc->tries[dev->devno] = min(ehc->tries[dev->devno], 1);
3481		fallthrough;
3482	case -EIO:
3483		if (ehc->tries[dev->devno] == 1) {
3484			/* This is the last chance, better to slow
3485			 * down than lose it.
3486			 */
3487			sata_down_spd_limit(ata_dev_phys_link(dev), 0);
3488			if (dev->pio_mode > XFER_PIO_0)
3489				ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
3490		}
3491	}
3492
3493	if (ata_dev_enabled(dev) && !ehc->tries[dev->devno]) {
3494		/* disable device if it has used up all its chances */
3495		ata_dev_disable(dev);
3496
3497		/* detach if offline */
3498		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
3499			ata_eh_detach_dev(dev);
3500
3501		/* schedule probe if necessary */
3502		if (ata_eh_schedule_probe(dev)) {
3503			ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3504			memset(ehc->cmd_timeout_idx[dev->devno], 0,
3505			       sizeof(ehc->cmd_timeout_idx[dev->devno]));
3506		}
3507
3508		return 1;
3509	} else {
3510		ehc->i.action |= ATA_EH_RESET;
3511		return 0;
3512	}
3513}
3514
3515/**
3516 *	ata_eh_recover - recover host port after error
3517 *	@ap: host port to recover
3518 *	@prereset: prereset method (can be NULL)
3519 *	@softreset: softreset method (can be NULL)
3520 *	@hardreset: hardreset method (can be NULL)
3521 *	@postreset: postreset method (can be NULL)
3522 *	@r_failed_link: out parameter for failed link
3523 *
3524 *	This is the alpha and omega, eum and yang, heart and soul of
3525 *	libata exception handling.  On entry, actions required to
3526 *	recover each link and hotplug requests are recorded in the
3527 *	link's eh_context.  This function executes all the operations
3528 *	with appropriate retrials and fallbacks to resurrect failed
3529 *	devices, detach goners and greet newcomers.
3530 *
3531 *	LOCKING:
3532 *	Kernel thread context (may sleep).
3533 *
3534 *	RETURNS:
3535 *	0 on success, -errno on failure.
3536 */
3537int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
3538		   ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3539		   ata_postreset_fn_t postreset,
3540		   struct ata_link **r_failed_link)
3541{
3542	struct ata_link *link;
3543	struct ata_device *dev;
3544	int rc, nr_fails;
3545	unsigned long flags, deadline;
3546
3547	DPRINTK("ENTER\n");
3548
3549	/* prep for recovery */
3550	ata_for_each_link(link, ap, EDGE) {
3551		struct ata_eh_context *ehc = &link->eh_context;
3552
3553		/* re-enable link? */
3554		if (ehc->i.action & ATA_EH_ENABLE_LINK) {
3555			ata_eh_about_to_do(link, NULL, ATA_EH_ENABLE_LINK);
3556			spin_lock_irqsave(ap->lock, flags);
3557			link->flags &= ~ATA_LFLAG_DISABLED;
3558			spin_unlock_irqrestore(ap->lock, flags);
3559			ata_eh_done(link, NULL, ATA_EH_ENABLE_LINK);
3560		}
3561
3562		ata_for_each_dev(dev, link, ALL) {
3563			if (link->flags & ATA_LFLAG_NO_RETRY)
3564				ehc->tries[dev->devno] = 1;
3565			else
3566				ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3567
3568			/* collect port action mask recorded in dev actions */
3569			ehc->i.action |= ehc->i.dev_action[dev->devno] &
3570					 ~ATA_EH_PERDEV_MASK;
3571			ehc->i.dev_action[dev->devno] &= ATA_EH_PERDEV_MASK;
3572
3573			/* process hotplug request */
3574			if (dev->flags & ATA_DFLAG_DETACH)
3575				ata_eh_detach_dev(dev);
3576
3577			/* schedule probe if necessary */
3578			if (!ata_dev_enabled(dev))
3579				ata_eh_schedule_probe(dev);
3580		}
3581	}
3582
3583 retry:
3584	rc = 0;
3585
3586	/* if UNLOADING, finish immediately */
3587	if (ap->pflags & ATA_PFLAG_UNLOADING)
3588		goto out;
3589
3590	/* prep for EH */
3591	ata_for_each_link(link, ap, EDGE) {
3592		struct ata_eh_context *ehc = &link->eh_context;
3593
3594		/* skip EH if possible. */
3595		if (ata_eh_skip_recovery(link))
3596			ehc->i.action = 0;
3597
3598		ata_for_each_dev(dev, link, ALL)
3599			ehc->classes[dev->devno] = ATA_DEV_UNKNOWN;
3600	}
3601
3602	/* reset */
3603	ata_for_each_link(link, ap, EDGE) {
3604		struct ata_eh_context *ehc = &link->eh_context;
3605
3606		if (!(ehc->i.action & ATA_EH_RESET))
3607			continue;
3608
3609		rc = ata_eh_reset(link, ata_link_nr_vacant(link),
3610				  prereset, softreset, hardreset, postreset);
3611		if (rc) {
3612			ata_link_err(link, "reset failed, giving up\n");
3613			goto out;
3614		}
3615	}
3616
3617	do {
3618		unsigned long now;
3619
3620		/*
3621		 * clears ATA_EH_PARK in eh_info and resets
3622		 * ap->park_req_pending
3623		 */
3624		ata_eh_pull_park_action(ap);
3625
3626		deadline = jiffies;
3627		ata_for_each_link(link, ap, EDGE) {
3628			ata_for_each_dev(dev, link, ALL) {
3629				struct ata_eh_context *ehc = &link->eh_context;
3630				unsigned long tmp;
3631
3632				if (dev->class != ATA_DEV_ATA &&
3633				    dev->class != ATA_DEV_ZAC)
3634					continue;
3635				if (!(ehc->i.dev_action[dev->devno] &
3636				      ATA_EH_PARK))
3637					continue;
3638				tmp = dev->unpark_deadline;
3639				if (time_before(deadline, tmp))
3640					deadline = tmp;
3641				else if (time_before_eq(tmp, jiffies))
3642					continue;
3643				if (ehc->unloaded_mask & (1 << dev->devno))
3644					continue;
3645
3646				ata_eh_park_issue_cmd(dev, 1);
3647			}
3648		}
3649
3650		now = jiffies;
3651		if (time_before_eq(deadline, now))
3652			break;
3653
3654		ata_eh_release(ap);
3655		deadline = wait_for_completion_timeout(&ap->park_req_pending,
3656						       deadline - now);
3657		ata_eh_acquire(ap);
3658	} while (deadline);
3659	ata_for_each_link(link, ap, EDGE) {
3660		ata_for_each_dev(dev, link, ALL) {
3661			if (!(link->eh_context.unloaded_mask &
3662			      (1 << dev->devno)))
3663				continue;
3664
3665			ata_eh_park_issue_cmd(dev, 0);
3666			ata_eh_done(link, dev, ATA_EH_PARK);
3667		}
3668	}
3669
3670	/* the rest */
3671	nr_fails = 0;
3672	ata_for_each_link(link, ap, PMP_FIRST) {
3673		struct ata_eh_context *ehc = &link->eh_context;
3674
3675		if (sata_pmp_attached(ap) && ata_is_host_link(link))
3676			goto config_lpm;
3677
3678		/* revalidate existing devices and attach new ones */
3679		rc = ata_eh_revalidate_and_attach(link, &dev);
3680		if (rc)
3681			goto rest_fail;
3682
3683		/* if PMP got attached, return, pmp EH will take care of it */
3684		if (link->device->class == ATA_DEV_PMP) {
3685			ehc->i.action = 0;
3686			return 0;
3687		}
3688
3689		/* configure transfer mode if necessary */
3690		if (ehc->i.flags & ATA_EHI_SETMODE) {
3691			rc = ata_set_mode(link, &dev);
3692			if (rc)
3693				goto rest_fail;
3694			ehc->i.flags &= ~ATA_EHI_SETMODE;
3695		}
3696
3697		/* If reset has been issued, clear UA to avoid
3698		 * disrupting the current users of the device.
3699		 */
3700		if (ehc->i.flags & ATA_EHI_DID_RESET) {
3701			ata_for_each_dev(dev, link, ALL) {
3702				if (dev->class != ATA_DEV_ATAPI)
3703					continue;
3704				rc = atapi_eh_clear_ua(dev);
3705				if (rc)
3706					goto rest_fail;
3707				if (zpodd_dev_enabled(dev))
3708					zpodd_post_poweron(dev);
3709			}
3710		}
3711
3712		/* retry flush if necessary */
3713		ata_for_each_dev(dev, link, ALL) {
3714			if (dev->class != ATA_DEV_ATA &&
3715			    dev->class != ATA_DEV_ZAC)
3716				continue;
3717			rc = ata_eh_maybe_retry_flush(dev);
3718			if (rc)
3719				goto rest_fail;
3720		}
3721
3722	config_lpm:
3723		/* configure link power saving */
3724		if (link->lpm_policy != ap->target_lpm_policy) {
3725			rc = ata_eh_set_lpm(link, ap->target_lpm_policy, &dev);
3726			if (rc)
3727				goto rest_fail;
3728		}
3729
3730		/* this link is okay now */
3731		ehc->i.flags = 0;
3732		continue;
3733
3734	rest_fail:
3735		nr_fails++;
3736		if (dev)
3737			ata_eh_handle_dev_fail(dev, rc);
3738
3739		if (ap->pflags & ATA_PFLAG_FROZEN) {
3740			/* PMP reset requires working host port.
3741			 * Can't retry if it's frozen.
3742			 */
3743			if (sata_pmp_attached(ap))
3744				goto out;
3745			break;
3746		}
3747	}
3748
3749	if (nr_fails)
3750		goto retry;
3751
3752 out:
3753	if (rc && r_failed_link)
3754		*r_failed_link = link;
3755
3756	DPRINTK("EXIT, rc=%d\n", rc);
3757	return rc;
3758}
3759
3760/**
3761 *	ata_eh_finish - finish up EH
3762 *	@ap: host port to finish EH for
3763 *
3764 *	Recovery is complete.  Clean up EH states and retry or finish
3765 *	failed qcs.
3766 *
3767 *	LOCKING:
3768 *	None.
3769 */
3770void ata_eh_finish(struct ata_port *ap)
3771{
3772	struct ata_queued_cmd *qc;
3773	int tag;
3774
3775	/* retry or finish qcs */
3776	ata_qc_for_each_raw(ap, qc, tag) {
3777		if (!(qc->flags & ATA_QCFLAG_FAILED))
3778			continue;
3779
3780		if (qc->err_mask) {
3781			/* FIXME: Once EH migration is complete,
3782			 * generate sense data in this function,
3783			 * considering both err_mask and tf.
3784			 */
3785			if (qc->flags & ATA_QCFLAG_RETRY)
3786				ata_eh_qc_retry(qc);
3787			else
3788				ata_eh_qc_complete(qc);
3789		} else {
3790			if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
3791				ata_eh_qc_complete(qc);
3792			} else {
3793				/* feed zero TF to sense generation */
3794				memset(&qc->result_tf, 0, sizeof(qc->result_tf));
3795				ata_eh_qc_retry(qc);
3796			}
3797		}
3798	}
3799
3800	/* make sure nr_active_links is zero after EH */
3801	WARN_ON(ap->nr_active_links);
3802	ap->nr_active_links = 0;
3803}
3804
3805/**
3806 *	ata_do_eh - do standard error handling
3807 *	@ap: host port to handle error for
3808 *
3809 *	@prereset: prereset method (can be NULL)
3810 *	@softreset: softreset method (can be NULL)
3811 *	@hardreset: hardreset method (can be NULL)
3812 *	@postreset: postreset method (can be NULL)
3813 *
3814 *	Perform standard error handling sequence.
3815 *
3816 *	LOCKING:
3817 *	Kernel thread context (may sleep).
3818 */
3819void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
3820	       ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3821	       ata_postreset_fn_t postreset)
3822{
3823	struct ata_device *dev;
3824	int rc;
3825
3826	ata_eh_autopsy(ap);
3827	ata_eh_report(ap);
3828
3829	rc = ata_eh_recover(ap, prereset, softreset, hardreset, postreset,
3830			    NULL);
3831	if (rc) {
3832		ata_for_each_dev(dev, &ap->link, ALL)
3833			ata_dev_disable(dev);
3834	}
3835
3836	ata_eh_finish(ap);
3837}
3838
3839/**
3840 *	ata_std_error_handler - standard error handler
3841 *	@ap: host port to handle error for
3842 *
3843 *	Standard error handler
3844 *
3845 *	LOCKING:
3846 *	Kernel thread context (may sleep).
3847 */
3848void ata_std_error_handler(struct ata_port *ap)
3849{
3850	struct ata_port_operations *ops = ap->ops;
3851	ata_reset_fn_t hardreset = ops->hardreset;
3852
3853	/* ignore built-in hardreset if SCR access is not available */
3854	if (hardreset == sata_std_hardreset && !sata_scr_valid(&ap->link))
3855		hardreset = NULL;
3856
3857	ata_do_eh(ap, ops->prereset, ops->softreset, hardreset, ops->postreset);
3858}
3859EXPORT_SYMBOL_GPL(ata_std_error_handler);
3860
3861#ifdef CONFIG_PM
3862/**
3863 *	ata_eh_handle_port_suspend - perform port suspend operation
3864 *	@ap: port to suspend
3865 *
3866 *	Suspend @ap.
3867 *
3868 *	LOCKING:
3869 *	Kernel thread context (may sleep).
3870 */
3871static void ata_eh_handle_port_suspend(struct ata_port *ap)
3872{
3873	unsigned long flags;
3874	int rc = 0;
3875	struct ata_device *dev;
3876
3877	/* are we suspending? */
3878	spin_lock_irqsave(ap->lock, flags);
3879	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
3880	    ap->pm_mesg.event & PM_EVENT_RESUME) {
3881		spin_unlock_irqrestore(ap->lock, flags);
3882		return;
3883	}
3884	spin_unlock_irqrestore(ap->lock, flags);
3885
3886	WARN_ON(ap->pflags & ATA_PFLAG_SUSPENDED);
3887
3888	/*
3889	 * If we have a ZPODD attached, check its zero
3890	 * power ready status before the port is frozen.
3891	 * Only needed for runtime suspend.
3892	 */
3893	if (PMSG_IS_AUTO(ap->pm_mesg)) {
3894		ata_for_each_dev(dev, &ap->link, ENABLED) {
3895			if (zpodd_dev_enabled(dev))
3896				zpodd_on_suspend(dev);
3897		}
3898	}
3899
3900	/* tell ACPI we're suspending */
3901	rc = ata_acpi_on_suspend(ap);
3902	if (rc)
3903		goto out;
3904
3905	/* suspend */
3906	ata_eh_freeze_port(ap);
3907
3908	if (ap->ops->port_suspend)
3909		rc = ap->ops->port_suspend(ap, ap->pm_mesg);
3910
3911	ata_acpi_set_state(ap, ap->pm_mesg);
3912 out:
3913	/* update the flags */
3914	spin_lock_irqsave(ap->lock, flags);
3915
3916	ap->pflags &= ~ATA_PFLAG_PM_PENDING;
3917	if (rc == 0)
3918		ap->pflags |= ATA_PFLAG_SUSPENDED;
3919	else if (ap->pflags & ATA_PFLAG_FROZEN)
3920		ata_port_schedule_eh(ap);
3921
3922	spin_unlock_irqrestore(ap->lock, flags);
3923
3924	return;
3925}
3926
3927/**
3928 *	ata_eh_handle_port_resume - perform port resume operation
3929 *	@ap: port to resume
3930 *
3931 *	Resume @ap.
3932 *
3933 *	LOCKING:
3934 *	Kernel thread context (may sleep).
3935 */
3936static void ata_eh_handle_port_resume(struct ata_port *ap)
3937{
3938	struct ata_link *link;
3939	struct ata_device *dev;
3940	unsigned long flags;
3941
3942	/* are we resuming? */
3943	spin_lock_irqsave(ap->lock, flags);
3944	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
3945	    !(ap->pm_mesg.event & PM_EVENT_RESUME)) {
3946		spin_unlock_irqrestore(ap->lock, flags);
3947		return;
3948	}
3949	spin_unlock_irqrestore(ap->lock, flags);
3950
3951	WARN_ON(!(ap->pflags & ATA_PFLAG_SUSPENDED));
3952
3953	/*
3954	 * Error timestamps are in jiffies which doesn't run while
3955	 * suspended and PHY events during resume isn't too uncommon.
3956	 * When the two are combined, it can lead to unnecessary speed
3957	 * downs if the machine is suspended and resumed repeatedly.
3958	 * Clear error history.
3959	 */
3960	ata_for_each_link(link, ap, HOST_FIRST)
3961		ata_for_each_dev(dev, link, ALL)
3962			ata_ering_clear(&dev->ering);
3963
3964	ata_acpi_set_state(ap, ap->pm_mesg);
3965
3966	if (ap->ops->port_resume)
3967		ap->ops->port_resume(ap);
3968
3969	/* tell ACPI that we're resuming */
3970	ata_acpi_on_resume(ap);
3971
3972	/* update the flags */
3973	spin_lock_irqsave(ap->lock, flags);
3974	ap->pflags &= ~(ATA_PFLAG_PM_PENDING | ATA_PFLAG_SUSPENDED);
3975	spin_unlock_irqrestore(ap->lock, flags);
3976}
3977#endif /* CONFIG_PM */