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