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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 */
v6.13.7
   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  libata-eh.c - libata error handling
   4 *
   5 *  Copyright 2006 Tejun Heo <htejun@gmail.com>
   6 *
   7 *  libata documentation is available via 'make {ps|pdf}docs',
   8 *  as Documentation/driver-api/libata.rst
   9 *
  10 *  Hardware documentation available from http://www.t13.org/ and
  11 *  http://www.sata-io.org/
  12 */
  13
  14#include <linux/kernel.h>
  15#include <linux/blkdev.h>
  16#include <linux/export.h>
  17#include <linux/pci.h>
  18#include <scsi/scsi.h>
  19#include <scsi/scsi_host.h>
  20#include <scsi/scsi_eh.h>
  21#include <scsi/scsi_device.h>
  22#include <scsi/scsi_cmnd.h>
  23#include <scsi/scsi_dbg.h>
  24#include "../scsi/scsi_transport_api.h"
  25
  26#include <linux/libata.h>
  27
  28#include <trace/events/libata.h>
  29#include "libata.h"
  30
  31enum {
  32	/* speed down verdicts */
  33	ATA_EH_SPDN_NCQ_OFF		= (1 << 0),
  34	ATA_EH_SPDN_SPEED_DOWN		= (1 << 1),
  35	ATA_EH_SPDN_FALLBACK_TO_PIO	= (1 << 2),
  36	ATA_EH_SPDN_KEEP_ERRORS		= (1 << 3),
  37
  38	/* error flags */
  39	ATA_EFLAG_IS_IO			= (1 << 0),
  40	ATA_EFLAG_DUBIOUS_XFER		= (1 << 1),
  41	ATA_EFLAG_OLD_ER                = (1 << 31),
  42
  43	/* error categories */
  44	ATA_ECAT_NONE			= 0,
  45	ATA_ECAT_ATA_BUS		= 1,
  46	ATA_ECAT_TOUT_HSM		= 2,
  47	ATA_ECAT_UNK_DEV		= 3,
  48	ATA_ECAT_DUBIOUS_NONE		= 4,
  49	ATA_ECAT_DUBIOUS_ATA_BUS	= 5,
  50	ATA_ECAT_DUBIOUS_TOUT_HSM	= 6,
  51	ATA_ECAT_DUBIOUS_UNK_DEV	= 7,
  52	ATA_ECAT_NR			= 8,
  53
  54	ATA_EH_CMD_DFL_TIMEOUT		=  5000,
  55
  56	/* always put at least this amount of time between resets */
  57	ATA_EH_RESET_COOL_DOWN		=  5000,
  58
  59	/* Waiting in ->prereset can never be reliable.  It's
  60	 * sometimes nice to wait there but it can't be depended upon;
  61	 * otherwise, we wouldn't be resetting.  Just give it enough
  62	 * time for most drives to spin up.
  63	 */
  64	ATA_EH_PRERESET_TIMEOUT		= 10000,
  65	ATA_EH_FASTDRAIN_INTERVAL	=  3000,
  66
  67	ATA_EH_UA_TRIES			= 5,
  68
  69	/* probe speed down parameters, see ata_eh_schedule_probe() */
  70	ATA_EH_PROBE_TRIAL_INTERVAL	= 60000,	/* 1 min */
  71	ATA_EH_PROBE_TRIALS		= 2,
  72};
  73
  74/* The following table determines how we sequence resets.  Each entry
  75 * represents timeout for that try.  The first try can be soft or
  76 * hardreset.  All others are hardreset if available.  In most cases
  77 * the first reset w/ 10sec timeout should succeed.  Following entries
  78 * are mostly for error handling, hotplug and those outlier devices that
  79 * take an exceptionally long time to recover from reset.
  80 */
  81static const unsigned int ata_eh_reset_timeouts[] = {
  82	10000,	/* most drives spin up by 10sec */
  83	10000,	/* > 99% working drives spin up before 20sec */
  84	35000,	/* give > 30 secs of idleness for outlier devices */
  85	 5000,	/* and sweet one last chance */
  86	UINT_MAX, /* > 1 min has elapsed, give up */
  87};
  88
  89static const unsigned int ata_eh_identify_timeouts[] = {
  90	 5000,	/* covers > 99% of successes and not too boring on failures */
  91	10000,  /* combined time till here is enough even for media access */
  92	30000,	/* for true idiots */
  93	UINT_MAX,
  94};
  95
  96static const unsigned int ata_eh_revalidate_timeouts[] = {
  97	15000,	/* Some drives are slow to read log pages when waking-up */
  98	15000,  /* combined time till here is enough even for media access */
  99	UINT_MAX,
 100};
 101
 102static const unsigned int ata_eh_flush_timeouts[] = {
 103	15000,	/* be generous with flush */
 104	15000,  /* ditto */
 105	30000,	/* and even more generous */
 106	UINT_MAX,
 107};
 108
 109static const unsigned int ata_eh_other_timeouts[] = {
 110	 5000,	/* same rationale as identify timeout */
 111	10000,	/* ditto */
 112	/* but no merciful 30sec for other commands, it just isn't worth it */
 113	UINT_MAX,
 114};
 115
 116struct ata_eh_cmd_timeout_ent {
 117	const u8		*commands;
 118	const unsigned int	*timeouts;
 119};
 120
 121/* The following table determines timeouts to use for EH internal
 122 * commands.  Each table entry is a command class and matches the
 123 * commands the entry applies to and the timeout table to use.
 124 *
 125 * On the retry after a command timed out, the next timeout value from
 126 * the table is used.  If the table doesn't contain further entries,
 127 * the last value is used.
 128 *
 129 * ehc->cmd_timeout_idx keeps track of which timeout to use per
 130 * command class, so if SET_FEATURES times out on the first try, the
 131 * next try will use the second timeout value only for that class.
 132 */
 133#define CMDS(cmds...)	(const u8 []){ cmds, 0 }
 134static const struct ata_eh_cmd_timeout_ent
 135ata_eh_cmd_timeout_table[ATA_EH_CMD_TIMEOUT_TABLE_SIZE] = {
 136	{ .commands = CMDS(ATA_CMD_ID_ATA, ATA_CMD_ID_ATAPI),
 137	  .timeouts = ata_eh_identify_timeouts, },
 138	{ .commands = CMDS(ATA_CMD_READ_LOG_EXT, ATA_CMD_READ_LOG_DMA_EXT),
 139	  .timeouts = ata_eh_revalidate_timeouts, },
 140	{ .commands = CMDS(ATA_CMD_READ_NATIVE_MAX, ATA_CMD_READ_NATIVE_MAX_EXT),
 141	  .timeouts = ata_eh_other_timeouts, },
 142	{ .commands = CMDS(ATA_CMD_SET_MAX, ATA_CMD_SET_MAX_EXT),
 143	  .timeouts = ata_eh_other_timeouts, },
 144	{ .commands = CMDS(ATA_CMD_SET_FEATURES),
 145	  .timeouts = ata_eh_other_timeouts, },
 146	{ .commands = CMDS(ATA_CMD_INIT_DEV_PARAMS),
 147	  .timeouts = ata_eh_other_timeouts, },
 148	{ .commands = CMDS(ATA_CMD_FLUSH, ATA_CMD_FLUSH_EXT),
 149	  .timeouts = ata_eh_flush_timeouts },
 150	{ .commands = CMDS(ATA_CMD_VERIFY),
 151	  .timeouts = ata_eh_reset_timeouts },
 152};
 153#undef CMDS
 154
 155static void __ata_port_freeze(struct ata_port *ap);
 156static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
 157			  struct ata_device **r_failed_dev);
 158#ifdef CONFIG_PM
 159static void ata_eh_handle_port_suspend(struct ata_port *ap);
 160static void ata_eh_handle_port_resume(struct ata_port *ap);
 161#else /* CONFIG_PM */
 162static void ata_eh_handle_port_suspend(struct ata_port *ap)
 163{ }
 164
 165static void ata_eh_handle_port_resume(struct ata_port *ap)
 166{ }
 167#endif /* CONFIG_PM */
 168
 169static __printf(2, 0) void __ata_ehi_pushv_desc(struct ata_eh_info *ehi,
 170				 const char *fmt, va_list args)
 171{
 172	ehi->desc_len += vscnprintf(ehi->desc + ehi->desc_len,
 173				     ATA_EH_DESC_LEN - ehi->desc_len,
 174				     fmt, args);
 175}
 176
 177/**
 178 *	__ata_ehi_push_desc - push error description without adding separator
 179 *	@ehi: target EHI
 180 *	@fmt: printf format string
 181 *
 182 *	Format string according to @fmt and append it to @ehi->desc.
 183 *
 184 *	LOCKING:
 185 *	spin_lock_irqsave(host lock)
 186 */
 187void __ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 188{
 189	va_list args;
 190
 191	va_start(args, fmt);
 192	__ata_ehi_pushv_desc(ehi, fmt, args);
 193	va_end(args);
 194}
 195EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
 196
 197/**
 198 *	ata_ehi_push_desc - push error description with separator
 199 *	@ehi: target EHI
 200 *	@fmt: printf format string
 201 *
 202 *	Format string according to @fmt and append it to @ehi->desc.
 203 *	If @ehi->desc is not empty, ", " is added in-between.
 204 *
 205 *	LOCKING:
 206 *	spin_lock_irqsave(host lock)
 207 */
 208void ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 209{
 210	va_list args;
 211
 212	if (ehi->desc_len)
 213		__ata_ehi_push_desc(ehi, ", ");
 214
 215	va_start(args, fmt);
 216	__ata_ehi_pushv_desc(ehi, fmt, args);
 217	va_end(args);
 218}
 219EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
 220
 221/**
 222 *	ata_ehi_clear_desc - clean error description
 223 *	@ehi: target EHI
 224 *
 225 *	Clear @ehi->desc.
 226 *
 227 *	LOCKING:
 228 *	spin_lock_irqsave(host lock)
 229 */
 230void ata_ehi_clear_desc(struct ata_eh_info *ehi)
 231{
 232	ehi->desc[0] = '\0';
 233	ehi->desc_len = 0;
 234}
 235EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
 236
 237/**
 238 *	ata_port_desc - append port description
 239 *	@ap: target ATA port
 240 *	@fmt: printf format string
 241 *
 242 *	Format string according to @fmt and append it to port
 243 *	description.  If port description is not empty, " " is added
 244 *	in-between.  This function is to be used while initializing
 245 *	ata_host.  The description is printed on host registration.
 246 *
 247 *	LOCKING:
 248 *	None.
 249 */
 250void ata_port_desc(struct ata_port *ap, const char *fmt, ...)
 251{
 252	va_list args;
 253
 254	WARN_ON(!(ap->pflags & ATA_PFLAG_INITIALIZING));
 255
 256	if (ap->link.eh_info.desc_len)
 257		__ata_ehi_push_desc(&ap->link.eh_info, " ");
 258
 259	va_start(args, fmt);
 260	__ata_ehi_pushv_desc(&ap->link.eh_info, fmt, args);
 261	va_end(args);
 262}
 263EXPORT_SYMBOL_GPL(ata_port_desc);
 264
 265#ifdef CONFIG_PCI
 266/**
 267 *	ata_port_pbar_desc - append PCI BAR description
 268 *	@ap: target ATA port
 269 *	@bar: target PCI BAR
 270 *	@offset: offset into PCI BAR
 271 *	@name: name of the area
 272 *
 273 *	If @offset is negative, this function formats a string which
 274 *	contains the name, address, size and type of the BAR and
 275 *	appends it to the port description.  If @offset is zero or
 276 *	positive, only name and offsetted address is appended.
 277 *
 278 *	LOCKING:
 279 *	None.
 280 */
 281void ata_port_pbar_desc(struct ata_port *ap, int bar, ssize_t offset,
 282			const char *name)
 283{
 284	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 285	char *type = "";
 286	unsigned long long start, len;
 287
 288	if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
 289		type = "m";
 290	else if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
 291		type = "i";
 292
 293	start = (unsigned long long)pci_resource_start(pdev, bar);
 294	len = (unsigned long long)pci_resource_len(pdev, bar);
 295
 296	if (offset < 0)
 297		ata_port_desc(ap, "%s %s%llu@0x%llx", name, type, len, start);
 298	else
 299		ata_port_desc(ap, "%s 0x%llx", name,
 300				start + (unsigned long long)offset);
 301}
 302EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
 303#endif /* CONFIG_PCI */
 304
 305static int ata_lookup_timeout_table(u8 cmd)
 306{
 307	int i;
 308
 309	for (i = 0; i < ATA_EH_CMD_TIMEOUT_TABLE_SIZE; i++) {
 310		const u8 *cur;
 311
 312		for (cur = ata_eh_cmd_timeout_table[i].commands; *cur; cur++)
 313			if (*cur == cmd)
 314				return i;
 315	}
 316
 317	return -1;
 318}
 319
 320/**
 321 *	ata_internal_cmd_timeout - determine timeout for an internal command
 322 *	@dev: target device
 323 *	@cmd: internal command to be issued
 324 *
 325 *	Determine timeout for internal command @cmd for @dev.
 326 *
 327 *	LOCKING:
 328 *	EH context.
 329 *
 330 *	RETURNS:
 331 *	Determined timeout.
 332 */
 333unsigned int ata_internal_cmd_timeout(struct ata_device *dev, u8 cmd)
 334{
 335	struct ata_eh_context *ehc = &dev->link->eh_context;
 336	int ent = ata_lookup_timeout_table(cmd);
 337	int idx;
 338
 339	if (ent < 0)
 340		return ATA_EH_CMD_DFL_TIMEOUT;
 341
 342	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 343	return ata_eh_cmd_timeout_table[ent].timeouts[idx];
 344}
 345
 346/**
 347 *	ata_internal_cmd_timed_out - notification for internal command timeout
 348 *	@dev: target device
 349 *	@cmd: internal command which timed out
 350 *
 351 *	Notify EH that internal command @cmd for @dev timed out.  This
 352 *	function should be called only for commands whose timeouts are
 353 *	determined using ata_internal_cmd_timeout().
 354 *
 355 *	LOCKING:
 356 *	EH context.
 357 */
 358void ata_internal_cmd_timed_out(struct ata_device *dev, u8 cmd)
 359{
 360	struct ata_eh_context *ehc = &dev->link->eh_context;
 361	int ent = ata_lookup_timeout_table(cmd);
 362	int idx;
 363
 364	if (ent < 0)
 365		return;
 366
 367	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 368	if (ata_eh_cmd_timeout_table[ent].timeouts[idx + 1] != UINT_MAX)
 369		ehc->cmd_timeout_idx[dev->devno][ent]++;
 370}
 371
 372static void ata_ering_record(struct ata_ering *ering, unsigned int eflags,
 373			     unsigned int err_mask)
 374{
 375	struct ata_ering_entry *ent;
 376
 377	WARN_ON(!err_mask);
 378
 379	ering->cursor++;
 380	ering->cursor %= ATA_ERING_SIZE;
 381
 382	ent = &ering->ring[ering->cursor];
 383	ent->eflags = eflags;
 384	ent->err_mask = err_mask;
 385	ent->timestamp = get_jiffies_64();
 386}
 387
 388static struct ata_ering_entry *ata_ering_top(struct ata_ering *ering)
 389{
 390	struct ata_ering_entry *ent = &ering->ring[ering->cursor];
 391
 392	if (ent->err_mask)
 393		return ent;
 394	return NULL;
 395}
 396
 397int ata_ering_map(struct ata_ering *ering,
 398		  int (*map_fn)(struct ata_ering_entry *, void *),
 399		  void *arg)
 400{
 401	int idx, rc = 0;
 402	struct ata_ering_entry *ent;
 403
 404	idx = ering->cursor;
 405	do {
 406		ent = &ering->ring[idx];
 407		if (!ent->err_mask)
 408			break;
 409		rc = map_fn(ent, arg);
 410		if (rc)
 411			break;
 412		idx = (idx - 1 + ATA_ERING_SIZE) % ATA_ERING_SIZE;
 413	} while (idx != ering->cursor);
 414
 415	return rc;
 416}
 417
 418static int ata_ering_clear_cb(struct ata_ering_entry *ent, void *void_arg)
 419{
 420	ent->eflags |= ATA_EFLAG_OLD_ER;
 421	return 0;
 422}
 423
 424static void ata_ering_clear(struct ata_ering *ering)
 425{
 426	ata_ering_map(ering, ata_ering_clear_cb, NULL);
 427}
 428
 429static unsigned int ata_eh_dev_action(struct ata_device *dev)
 430{
 431	struct ata_eh_context *ehc = &dev->link->eh_context;
 432
 433	return ehc->i.action | ehc->i.dev_action[dev->devno];
 434}
 435
 436static void ata_eh_clear_action(struct ata_link *link, struct ata_device *dev,
 437				struct ata_eh_info *ehi, unsigned int action)
 438{
 439	struct ata_device *tdev;
 440
 441	if (!dev) {
 442		ehi->action &= ~action;
 443		ata_for_each_dev(tdev, link, ALL)
 444			ehi->dev_action[tdev->devno] &= ~action;
 445	} else {
 446		/* doesn't make sense for port-wide EH actions */
 447		WARN_ON(!(action & ATA_EH_PERDEV_MASK));
 448
 449		/* break ehi->action into ehi->dev_action */
 450		if (ehi->action & action) {
 451			ata_for_each_dev(tdev, link, ALL)
 452				ehi->dev_action[tdev->devno] |=
 453					ehi->action & action;
 454			ehi->action &= ~action;
 455		}
 456
 457		/* turn off the specified per-dev action */
 458		ehi->dev_action[dev->devno] &= ~action;
 459	}
 460}
 461
 462/**
 463 *	ata_eh_acquire - acquire EH ownership
 464 *	@ap: ATA port to acquire EH ownership for
 465 *
 466 *	Acquire EH ownership for @ap.  This is the basic exclusion
 467 *	mechanism for ports sharing a host.  Only one port hanging off
 468 *	the same host can claim the ownership of EH.
 469 *
 470 *	LOCKING:
 471 *	EH context.
 472 */
 473void ata_eh_acquire(struct ata_port *ap)
 474{
 475	mutex_lock(&ap->host->eh_mutex);
 476	WARN_ON_ONCE(ap->host->eh_owner);
 477	ap->host->eh_owner = current;
 478}
 479
 480/**
 481 *	ata_eh_release - release EH ownership
 482 *	@ap: ATA port to release EH ownership for
 483 *
 484 *	Release EH ownership for @ap if the caller.  The caller must
 485 *	have acquired EH ownership using ata_eh_acquire() previously.
 486 *
 487 *	LOCKING:
 488 *	EH context.
 489 */
 490void ata_eh_release(struct ata_port *ap)
 491{
 492	WARN_ON_ONCE(ap->host->eh_owner != current);
 493	ap->host->eh_owner = NULL;
 494	mutex_unlock(&ap->host->eh_mutex);
 495}
 496
 497static void ata_eh_dev_disable(struct ata_device *dev)
 498{
 499	ata_acpi_on_disable(dev);
 500	ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 | ATA_DNXFER_QUIET);
 501	dev->class++;
 502
 503	/*
 504	 * From now till the next successful probe, ering is used to
 505	 * track probe failures.  Clear accumulated device error info.
 506	 */
 507	ata_ering_clear(&dev->ering);
 508
 509	ata_dev_free_resources(dev);
 510}
 511
 512static void ata_eh_unload(struct ata_port *ap)
 513{
 514	struct ata_link *link;
 515	struct ata_device *dev;
 516	unsigned long flags;
 517
 518	/*
 519	 * Unless we are restarting, transition all enabled devices to
 520	 * standby power mode.
 521	 */
 522	if (system_state != SYSTEM_RESTART) {
 523		ata_for_each_link(link, ap, PMP_FIRST) {
 524			ata_for_each_dev(dev, link, ENABLED)
 525				ata_dev_power_set_standby(dev);
 526		}
 527	}
 528
 529	/*
 530	 * Restore SControl IPM and SPD for the next driver and
 531	 * disable attached devices.
 532	 */
 533	ata_for_each_link(link, ap, PMP_FIRST) {
 534		sata_scr_write(link, SCR_CONTROL, link->saved_scontrol & 0xff0);
 535		ata_for_each_dev(dev, link, ENABLED)
 536			ata_eh_dev_disable(dev);
 537	}
 538
 539	/* freeze and set UNLOADED */
 540	spin_lock_irqsave(ap->lock, flags);
 541
 542	ata_port_freeze(ap);			/* won't be thawed */
 543	ap->pflags &= ~ATA_PFLAG_EH_PENDING;	/* clear pending from freeze */
 544	ap->pflags |= ATA_PFLAG_UNLOADED;
 545
 546	spin_unlock_irqrestore(ap->lock, flags);
 547}
 548
 549/**
 550 *	ata_scsi_error - SCSI layer error handler callback
 551 *	@host: SCSI host on which error occurred
 552 *
 553 *	Handles SCSI-layer-thrown error events.
 554 *
 555 *	LOCKING:
 556 *	Inherited from SCSI layer (none, can sleep)
 557 *
 558 *	RETURNS:
 559 *	Zero.
 560 */
 561void ata_scsi_error(struct Scsi_Host *host)
 562{
 563	struct ata_port *ap = ata_shost_to_port(host);
 564	unsigned long flags;
 565	LIST_HEAD(eh_work_q);
 566
 
 
 567	spin_lock_irqsave(host->host_lock, flags);
 568	list_splice_init(&host->eh_cmd_q, &eh_work_q);
 569	spin_unlock_irqrestore(host->host_lock, flags);
 570
 571	ata_scsi_cmd_error_handler(host, ap, &eh_work_q);
 572
 573	/* If we timed raced normal completion and there is nothing to
 574	   recover nr_timedout == 0 why exactly are we doing error recovery ? */
 575	ata_scsi_port_error_handler(host, ap);
 576
 577	/* finish or retry handled scmd's and clean up */
 578	WARN_ON(!list_empty(&eh_work_q));
 579
 
 580}
 581
 582/**
 583 * ata_scsi_cmd_error_handler - error callback for a list of commands
 584 * @host:	scsi host containing the port
 585 * @ap:		ATA port within the host
 586 * @eh_work_q:	list of commands to process
 587 *
 588 * process the given list of commands and return those finished to the
 589 * ap->eh_done_q.  This function is the first part of the libata error
 590 * handler which processes a given list of failed commands.
 591 */
 592void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
 593				struct list_head *eh_work_q)
 594{
 595	int i;
 596	unsigned long flags;
 597	struct scsi_cmnd *scmd, *tmp;
 598	int nr_timedout = 0;
 599
 600	/* make sure sff pio task is not running */
 601	ata_sff_flush_pio_task(ap);
 602
 603	/* synchronize with host lock and sort out timeouts */
 604
 605	/*
 606	 * For EH, all qcs are finished in one of three ways -
 607	 * normal completion, error completion, and SCSI timeout.
 608	 * Both completions can race against SCSI timeout.  When normal
 609	 * completion wins, the qc never reaches EH.  When error
 610	 * completion wins, the qc has ATA_QCFLAG_EH set.
 611	 *
 612	 * When SCSI timeout wins, things are a bit more complex.
 613	 * Normal or error completion can occur after the timeout but
 614	 * before this point.  In such cases, both types of
 615	 * completions are honored.  A scmd is determined to have
 616	 * timed out iff its associated qc is active and not failed.
 617	 */
 618	spin_lock_irqsave(ap->lock, flags);
 
 
 
 
 
 
 619
 620	/*
 621	 * This must occur under the ap->lock as we don't want
 622	 * a polled recovery to race the real interrupt handler
 623	 *
 624	 * The lost_interrupt handler checks for any completed but
 625	 * non-notified command and completes much like an IRQ handler.
 626	 *
 627	 * We then fall into the error recovery code which will treat
 628	 * this as if normal completion won the race
 629	 */
 630	if (ap->ops->lost_interrupt)
 631		ap->ops->lost_interrupt(ap);
 632
 633	list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
 634		struct ata_queued_cmd *qc;
 635
 636		/*
 637		 * If the scmd was added to EH, via ata_qc_schedule_eh() ->
 638		 * scsi_timeout() -> scsi_eh_scmd_add(), scsi_timeout() will
 639		 * have set DID_TIME_OUT (since libata does not have an abort
 640		 * handler). Thus, to clear DID_TIME_OUT, clear the host byte.
 641		 */
 642		set_host_byte(scmd, DID_OK);
 643
 644		ata_qc_for_each_raw(ap, qc, i) {
 645			if (qc->flags & ATA_QCFLAG_ACTIVE &&
 646			    qc->scsicmd == scmd)
 647				break;
 648		}
 649
 650		if (i < ATA_MAX_QUEUE) {
 651			/* the scmd has an associated qc */
 652			if (!(qc->flags & ATA_QCFLAG_EH)) {
 653				/* which hasn't failed yet, timeout */
 654				set_host_byte(scmd, DID_TIME_OUT);
 655				qc->err_mask |= AC_ERR_TIMEOUT;
 656				qc->flags |= ATA_QCFLAG_EH;
 657				nr_timedout++;
 
 
 
 
 
 
 
 658			}
 659		} else {
 660			/* Normal completion occurred after
 661			 * SCSI timeout but before this point.
 662			 * Successfully complete it.
 663			 */
 664			scmd->retries = scmd->allowed;
 665			scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
 666		}
 667	}
 668
 669	/*
 670	 * If we have timed out qcs.  They belong to EH from
 671	 * this point but the state of the controller is
 672	 * unknown.  Freeze the port to make sure the IRQ
 673	 * handler doesn't diddle with those qcs.  This must
 674	 * be done atomically w.r.t. setting ATA_QCFLAG_EH.
 675	 */
 676	if (nr_timedout)
 677		__ata_port_freeze(ap);
 678
 679	/* initialize eh_tries */
 680	ap->eh_tries = ATA_EH_MAX_TRIES;
 681
 
 
 
 682	spin_unlock_irqrestore(ap->lock, flags);
 
 683}
 684EXPORT_SYMBOL(ata_scsi_cmd_error_handler);
 685
 686/**
 687 * ata_scsi_port_error_handler - recover the port after the commands
 688 * @host:	SCSI host containing the port
 689 * @ap:		the ATA port
 690 *
 691 * Handle the recovery of the port @ap after all the commands
 692 * have been recovered.
 693 */
 694void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap)
 695{
 696	unsigned long flags;
 697	struct ata_link *link;
 698
 699	/* acquire EH ownership */
 700	ata_eh_acquire(ap);
 
 
 
 
 701 repeat:
 702	/* kill fast drain timer */
 703	del_timer_sync(&ap->fastdrain_timer);
 704
 705	/* process port resume request */
 706	ata_eh_handle_port_resume(ap);
 707
 708	/* fetch & clear EH info */
 709	spin_lock_irqsave(ap->lock, flags);
 710
 711	ata_for_each_link(link, ap, HOST_FIRST) {
 712		struct ata_eh_context *ehc = &link->eh_context;
 713		struct ata_device *dev;
 714
 715		memset(&link->eh_context, 0, sizeof(link->eh_context));
 716		link->eh_context.i = link->eh_info;
 717		memset(&link->eh_info, 0, sizeof(link->eh_info));
 718
 719		ata_for_each_dev(dev, link, ENABLED) {
 720			int devno = dev->devno;
 721
 722			ehc->saved_xfer_mode[devno] = dev->xfer_mode;
 723			if (ata_ncq_enabled(dev))
 724				ehc->saved_ncq_enabled |= 1 << devno;
 725
 726			/* If we are resuming, wake up the device */
 727			if (ap->pflags & ATA_PFLAG_RESUMING) {
 728				dev->flags |= ATA_DFLAG_RESUMING;
 729				ehc->i.dev_action[devno] |= ATA_EH_SET_ACTIVE;
 730			}
 731		}
 732	}
 733
 734	ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
 735	ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 736	ap->excl_link = NULL;	/* don't maintain exclusion over EH */
 737
 738	spin_unlock_irqrestore(ap->lock, flags);
 739
 740	/* invoke EH, skip if unloading or suspended */
 741	if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))
 742		ap->ops->error_handler(ap);
 743	else {
 744		/* if unloading, commence suicide */
 745		if ((ap->pflags & ATA_PFLAG_UNLOADING) &&
 746		    !(ap->pflags & ATA_PFLAG_UNLOADED))
 747			ata_eh_unload(ap);
 748		ata_eh_finish(ap);
 749	}
 
 
 
 
 
 
 
 
 
 750
 751	/* process port suspend request */
 752	ata_eh_handle_port_suspend(ap);
 
 
 
 
 
 
 
 
 753
 754	/*
 755	 * Exception might have happened after ->error_handler recovered the
 756	 * port but before this point.  Repeat EH in such case.
 757	 */
 758	spin_lock_irqsave(ap->lock, flags);
 
 
 
 
 
 759
 760	if (ap->pflags & ATA_PFLAG_EH_PENDING) {
 761		if (--ap->eh_tries) {
 762			spin_unlock_irqrestore(ap->lock, flags);
 763			goto repeat;
 764		}
 765		ata_port_err(ap,
 766			     "EH pending after %d tries, giving up\n",
 767			     ATA_EH_MAX_TRIES);
 768		ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 769	}
 770
 771	/* this run is complete, make sure EH info is clear */
 772	ata_for_each_link(link, ap, HOST_FIRST)
 773		memset(&link->eh_info, 0, sizeof(link->eh_info));
 774
 775	/*
 776	 * end eh (clear host_eh_scheduled) while holding ap->lock such that if
 777	 * exception occurs after this point but before EH completion, SCSI
 778	 * midlayer will re-initiate EH.
 779	 */
 780	ap->ops->end_eh(ap);
 781
 782	spin_unlock_irqrestore(ap->lock, flags);
 783	ata_eh_release(ap);
 784
 785	scsi_eh_flush_done_q(&ap->eh_done_q);
 786
 787	/* clean up */
 788	spin_lock_irqsave(ap->lock, flags);
 789
 790	ap->pflags &= ~ATA_PFLAG_RESUMING;
 791
 792	if (ap->pflags & ATA_PFLAG_LOADING)
 793		ap->pflags &= ~ATA_PFLAG_LOADING;
 794	else if ((ap->pflags & ATA_PFLAG_SCSI_HOTPLUG) &&
 795		!(ap->flags & ATA_FLAG_SAS_HOST))
 796		schedule_delayed_work(&ap->hotplug_task, 0);
 797
 798	if (ap->pflags & ATA_PFLAG_RECOVERED)
 799		ata_port_info(ap, "EH complete\n");
 800
 801	ap->pflags &= ~(ATA_PFLAG_SCSI_HOTPLUG | ATA_PFLAG_RECOVERED);
 802
 803	/* tell wait_eh that we're done */
 804	ap->pflags &= ~ATA_PFLAG_EH_IN_PROGRESS;
 805	wake_up_all(&ap->eh_wait_q);
 806
 807	spin_unlock_irqrestore(ap->lock, flags);
 808}
 809EXPORT_SYMBOL_GPL(ata_scsi_port_error_handler);
 810
 811/**
 812 *	ata_port_wait_eh - Wait for the currently pending EH to complete
 813 *	@ap: Port to wait EH for
 814 *
 815 *	Wait until the currently pending EH is complete.
 816 *
 817 *	LOCKING:
 818 *	Kernel thread context (may sleep).
 819 */
 820void ata_port_wait_eh(struct ata_port *ap)
 821{
 822	unsigned long flags;
 823	DEFINE_WAIT(wait);
 824
 825 retry:
 826	spin_lock_irqsave(ap->lock, flags);
 827
 828	while (ap->pflags & (ATA_PFLAG_EH_PENDING | ATA_PFLAG_EH_IN_PROGRESS)) {
 829		prepare_to_wait(&ap->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 830		spin_unlock_irqrestore(ap->lock, flags);
 831		schedule();
 832		spin_lock_irqsave(ap->lock, flags);
 833	}
 834	finish_wait(&ap->eh_wait_q, &wait);
 835
 836	spin_unlock_irqrestore(ap->lock, flags);
 837
 838	/* make sure SCSI EH is complete */
 839	if (scsi_host_in_recovery(ap->scsi_host)) {
 840		ata_msleep(ap, 10);
 841		goto retry;
 842	}
 843}
 844EXPORT_SYMBOL_GPL(ata_port_wait_eh);
 845
 846static unsigned int ata_eh_nr_in_flight(struct ata_port *ap)
 847{
 848	struct ata_queued_cmd *qc;
 849	unsigned int tag;
 850	unsigned int nr = 0;
 851
 852	/* count only non-internal commands */
 853	ata_qc_for_each(ap, qc, tag) {
 854		if (qc)
 855			nr++;
 856	}
 857
 858	return nr;
 859}
 860
 861void ata_eh_fastdrain_timerfn(struct timer_list *t)
 862{
 863	struct ata_port *ap = from_timer(ap, t, fastdrain_timer);
 864	unsigned long flags;
 865	unsigned int cnt;
 866
 867	spin_lock_irqsave(ap->lock, flags);
 868
 869	cnt = ata_eh_nr_in_flight(ap);
 870
 871	/* are we done? */
 872	if (!cnt)
 873		goto out_unlock;
 874
 875	if (cnt == ap->fastdrain_cnt) {
 876		struct ata_queued_cmd *qc;
 877		unsigned int tag;
 878
 879		/* No progress during the last interval, tag all
 880		 * in-flight qcs as timed out and freeze the port.
 881		 */
 882		ata_qc_for_each(ap, qc, tag) {
 883			if (qc)
 884				qc->err_mask |= AC_ERR_TIMEOUT;
 885		}
 886
 887		ata_port_freeze(ap);
 888	} else {
 889		/* some qcs have finished, give it another chance */
 890		ap->fastdrain_cnt = cnt;
 891		ap->fastdrain_timer.expires =
 892			ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 893		add_timer(&ap->fastdrain_timer);
 894	}
 895
 896 out_unlock:
 897	spin_unlock_irqrestore(ap->lock, flags);
 898}
 899
 900/**
 901 *	ata_eh_set_pending - set ATA_PFLAG_EH_PENDING and activate fast drain
 902 *	@ap: target ATA port
 903 *	@fastdrain: activate fast drain
 904 *
 905 *	Set ATA_PFLAG_EH_PENDING and activate fast drain if @fastdrain
 906 *	is non-zero and EH wasn't pending before.  Fast drain ensures
 907 *	that EH kicks in in timely manner.
 908 *
 909 *	LOCKING:
 910 *	spin_lock_irqsave(host lock)
 911 */
 912static void ata_eh_set_pending(struct ata_port *ap, int fastdrain)
 913{
 914	unsigned int cnt;
 915
 916	/* already scheduled? */
 917	if (ap->pflags & ATA_PFLAG_EH_PENDING)
 918		return;
 919
 920	ap->pflags |= ATA_PFLAG_EH_PENDING;
 921
 922	if (!fastdrain)
 923		return;
 924
 925	/* do we have in-flight qcs? */
 926	cnt = ata_eh_nr_in_flight(ap);
 927	if (!cnt)
 928		return;
 929
 930	/* activate fast drain */
 931	ap->fastdrain_cnt = cnt;
 932	ap->fastdrain_timer.expires =
 933		ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 934	add_timer(&ap->fastdrain_timer);
 935}
 936
 937/**
 938 *	ata_qc_schedule_eh - schedule qc for error handling
 939 *	@qc: command to schedule error handling for
 940 *
 941 *	Schedule error handling for @qc.  EH will kick in as soon as
 942 *	other commands are drained.
 943 *
 944 *	LOCKING:
 945 *	spin_lock_irqsave(host lock)
 946 */
 947void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
 948{
 949	struct ata_port *ap = qc->ap;
 950
 951	qc->flags |= ATA_QCFLAG_EH;
 
 
 952	ata_eh_set_pending(ap, 1);
 953
 954	/* The following will fail if timeout has already expired.
 955	 * ata_scsi_error() takes care of such scmds on EH entry.
 956	 * Note that ATA_QCFLAG_EH is unconditionally set after
 957	 * this function completes.
 958	 */
 959	blk_abort_request(scsi_cmd_to_rq(qc->scsicmd));
 960}
 961
 962/**
 963 * ata_std_sched_eh - non-libsas ata_ports issue eh with this common routine
 964 * @ap: ATA port to schedule EH for
 965 *
 966 *	LOCKING: inherited from ata_port_schedule_eh
 967 *	spin_lock_irqsave(host lock)
 968 */
 969void ata_std_sched_eh(struct ata_port *ap)
 970{
 
 
 971	if (ap->pflags & ATA_PFLAG_INITIALIZING)
 972		return;
 973
 974	ata_eh_set_pending(ap, 1);
 975	scsi_schedule_eh(ap->scsi_host);
 976
 977	trace_ata_std_sched_eh(ap);
 978}
 979EXPORT_SYMBOL_GPL(ata_std_sched_eh);
 980
 981/**
 982 * ata_std_end_eh - non-libsas ata_ports complete eh with this common routine
 983 * @ap: ATA port to end EH for
 984 *
 985 * In the libata object model there is a 1:1 mapping of ata_port to
 986 * shost, so host fields can be directly manipulated under ap->lock, in
 987 * the libsas case we need to hold a lock at the ha->level to coordinate
 988 * these events.
 989 *
 990 *	LOCKING:
 991 *	spin_lock_irqsave(host lock)
 992 */
 993void ata_std_end_eh(struct ata_port *ap)
 994{
 995	struct Scsi_Host *host = ap->scsi_host;
 996
 997	host->host_eh_scheduled = 0;
 998}
 999EXPORT_SYMBOL(ata_std_end_eh);
1000
1001
1002/**
1003 *	ata_port_schedule_eh - schedule error handling without a qc
1004 *	@ap: ATA port to schedule EH for
1005 *
1006 *	Schedule error handling for @ap.  EH will kick in as soon as
1007 *	all commands are drained.
1008 *
1009 *	LOCKING:
1010 *	spin_lock_irqsave(host lock)
1011 */
1012void ata_port_schedule_eh(struct ata_port *ap)
1013{
1014	/* see: ata_std_sched_eh, unless you know better */
1015	ap->ops->sched_eh(ap);
1016}
1017EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
1018
1019static int ata_do_link_abort(struct ata_port *ap, struct ata_link *link)
1020{
1021	struct ata_queued_cmd *qc;
1022	int tag, nr_aborted = 0;
1023
 
 
1024	/* we're gonna abort all commands, no need for fast drain */
1025	ata_eh_set_pending(ap, 0);
1026
1027	/* include internal tag in iteration */
1028	ata_qc_for_each_with_internal(ap, qc, tag) {
1029		if (qc && (!link || qc->dev->link == link)) {
1030			qc->flags |= ATA_QCFLAG_EH;
1031			ata_qc_complete(qc);
1032			nr_aborted++;
1033		}
1034	}
1035
1036	if (!nr_aborted)
1037		ata_port_schedule_eh(ap);
1038
1039	return nr_aborted;
1040}
1041
1042/**
1043 *	ata_link_abort - abort all qc's on the link
1044 *	@link: ATA link to abort qc's for
1045 *
1046 *	Abort all active qc's active on @link and schedule EH.
1047 *
1048 *	LOCKING:
1049 *	spin_lock_irqsave(host lock)
1050 *
1051 *	RETURNS:
1052 *	Number of aborted qc's.
1053 */
1054int ata_link_abort(struct ata_link *link)
1055{
1056	return ata_do_link_abort(link->ap, link);
1057}
1058EXPORT_SYMBOL_GPL(ata_link_abort);
1059
1060/**
1061 *	ata_port_abort - abort all qc's on the port
1062 *	@ap: ATA port to abort qc's for
1063 *
1064 *	Abort all active qc's of @ap and schedule EH.
1065 *
1066 *	LOCKING:
1067 *	spin_lock_irqsave(host_set lock)
1068 *
1069 *	RETURNS:
1070 *	Number of aborted qc's.
1071 */
1072int ata_port_abort(struct ata_port *ap)
1073{
1074	return ata_do_link_abort(ap, NULL);
1075}
1076EXPORT_SYMBOL_GPL(ata_port_abort);
1077
1078/**
1079 *	__ata_port_freeze - freeze port
1080 *	@ap: ATA port to freeze
1081 *
1082 *	This function is called when HSM violation or some other
1083 *	condition disrupts normal operation of the port.  Frozen port
1084 *	is not allowed to perform any operation until the port is
1085 *	thawed, which usually follows a successful reset.
1086 *
1087 *	ap->ops->freeze() callback can be used for freezing the port
1088 *	hardware-wise (e.g. mask interrupt and stop DMA engine).  If a
1089 *	port cannot be frozen hardware-wise, the interrupt handler
1090 *	must ack and clear interrupts unconditionally while the port
1091 *	is frozen.
1092 *
1093 *	LOCKING:
1094 *	spin_lock_irqsave(host lock)
1095 */
1096static void __ata_port_freeze(struct ata_port *ap)
1097{
 
 
1098	if (ap->ops->freeze)
1099		ap->ops->freeze(ap);
1100
1101	ap->pflags |= ATA_PFLAG_FROZEN;
1102
1103	trace_ata_port_freeze(ap);
1104}
1105
1106/**
1107 *	ata_port_freeze - abort & freeze port
1108 *	@ap: ATA port to freeze
1109 *
1110 *	Abort and freeze @ap.  The freeze operation must be called
1111 *	first, because some hardware requires special operations
1112 *	before the taskfile registers are accessible.
1113 *
1114 *	LOCKING:
1115 *	spin_lock_irqsave(host lock)
1116 *
1117 *	RETURNS:
1118 *	Number of aborted commands.
1119 */
1120int ata_port_freeze(struct ata_port *ap)
1121{
 
 
 
 
1122	__ata_port_freeze(ap);
 
1123
1124	return ata_port_abort(ap);
1125}
1126EXPORT_SYMBOL_GPL(ata_port_freeze);
1127
1128/**
1129 *	ata_eh_freeze_port - EH helper to freeze port
1130 *	@ap: ATA port to freeze
1131 *
1132 *	Freeze @ap.
1133 *
1134 *	LOCKING:
1135 *	None.
1136 */
1137void ata_eh_freeze_port(struct ata_port *ap)
1138{
1139	unsigned long flags;
1140
 
 
 
1141	spin_lock_irqsave(ap->lock, flags);
1142	__ata_port_freeze(ap);
1143	spin_unlock_irqrestore(ap->lock, flags);
1144}
1145EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
1146
1147/**
1148 *	ata_eh_thaw_port - EH helper to thaw port
1149 *	@ap: ATA port to thaw
1150 *
1151 *	Thaw frozen port @ap.
1152 *
1153 *	LOCKING:
1154 *	None.
1155 */
1156void ata_eh_thaw_port(struct ata_port *ap)
1157{
1158	unsigned long flags;
1159
 
 
 
1160	spin_lock_irqsave(ap->lock, flags);
1161
1162	ap->pflags &= ~ATA_PFLAG_FROZEN;
1163
1164	if (ap->ops->thaw)
1165		ap->ops->thaw(ap);
1166
1167	spin_unlock_irqrestore(ap->lock, flags);
1168
1169	trace_ata_port_thaw(ap);
1170}
1171
1172static void ata_eh_scsidone(struct scsi_cmnd *scmd)
1173{
1174	/* nada */
1175}
1176
1177static void __ata_eh_qc_complete(struct ata_queued_cmd *qc)
1178{
1179	struct ata_port *ap = qc->ap;
1180	struct scsi_cmnd *scmd = qc->scsicmd;
1181	unsigned long flags;
1182
1183	spin_lock_irqsave(ap->lock, flags);
1184	qc->scsidone = ata_eh_scsidone;
1185	__ata_qc_complete(qc);
1186	WARN_ON(ata_tag_valid(qc->tag));
1187	spin_unlock_irqrestore(ap->lock, flags);
1188
1189	scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
1190}
1191
1192/**
1193 *	ata_eh_qc_complete - Complete an active ATA command from EH
1194 *	@qc: Command to complete
1195 *
1196 *	Indicate to the mid and upper layers that an ATA command has
1197 *	completed.  To be used from EH.
1198 */
1199void ata_eh_qc_complete(struct ata_queued_cmd *qc)
1200{
1201	struct scsi_cmnd *scmd = qc->scsicmd;
1202	scmd->retries = scmd->allowed;
1203	__ata_eh_qc_complete(qc);
1204}
1205
1206/**
1207 *	ata_eh_qc_retry - Tell midlayer to retry an ATA command after EH
1208 *	@qc: Command to retry
1209 *
1210 *	Indicate to the mid and upper layers that an ATA command
1211 *	should be retried.  To be used from EH.
1212 *
1213 *	SCSI midlayer limits the number of retries to scmd->allowed.
1214 *	scmd->allowed is incremented for commands which get retried
1215 *	due to unrelated failures (qc->err_mask is zero).
1216 */
1217void ata_eh_qc_retry(struct ata_queued_cmd *qc)
1218{
1219	struct scsi_cmnd *scmd = qc->scsicmd;
1220	if (!qc->err_mask)
1221		scmd->allowed++;
1222	__ata_eh_qc_complete(qc);
1223}
1224
1225/**
1226 *	ata_dev_disable - disable ATA device
1227 *	@dev: ATA device to disable
1228 *
1229 *	Disable @dev.
1230 *
1231 *	Locking:
1232 *	EH context.
1233 */
1234void ata_dev_disable(struct ata_device *dev)
1235{
1236	if (!ata_dev_enabled(dev))
1237		return;
1238
1239	ata_dev_warn(dev, "disable device\n");
 
 
 
 
1240
1241	ata_eh_dev_disable(dev);
 
 
 
1242}
1243EXPORT_SYMBOL_GPL(ata_dev_disable);
1244
1245/**
1246 *	ata_eh_detach_dev - detach ATA device
1247 *	@dev: ATA device to detach
1248 *
1249 *	Detach @dev.
1250 *
1251 *	LOCKING:
1252 *	None.
1253 */
1254void ata_eh_detach_dev(struct ata_device *dev)
1255{
1256	struct ata_link *link = dev->link;
1257	struct ata_port *ap = link->ap;
1258	struct ata_eh_context *ehc = &link->eh_context;
1259	unsigned long flags;
1260
1261	/*
1262	 * If the device is still enabled, transition it to standby power mode
1263	 * (i.e. spin down HDDs) and disable it.
1264	 */
1265	if (ata_dev_enabled(dev)) {
1266		ata_dev_power_set_standby(dev);
1267		ata_eh_dev_disable(dev);
1268	}
1269
1270	spin_lock_irqsave(ap->lock, flags);
1271
1272	dev->flags &= ~ATA_DFLAG_DETACH;
1273
1274	if (ata_scsi_offline_dev(dev)) {
1275		dev->flags |= ATA_DFLAG_DETACHED;
1276		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
1277	}
1278
1279	/* clear per-dev EH info */
1280	ata_eh_clear_action(link, dev, &link->eh_info, ATA_EH_PERDEV_MASK);
1281	ata_eh_clear_action(link, dev, &link->eh_context.i, ATA_EH_PERDEV_MASK);
1282	ehc->saved_xfer_mode[dev->devno] = 0;
1283	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
1284
1285	spin_unlock_irqrestore(ap->lock, flags);
1286}
1287
1288/**
1289 *	ata_eh_about_to_do - about to perform eh_action
1290 *	@link: target ATA link
1291 *	@dev: target ATA dev for per-dev action (can be NULL)
1292 *	@action: action about to be performed
1293 *
1294 *	Called just before performing EH actions to clear related bits
1295 *	in @link->eh_info such that eh actions are not unnecessarily
1296 *	repeated.
1297 *
1298 *	LOCKING:
1299 *	None.
1300 */
1301void ata_eh_about_to_do(struct ata_link *link, struct ata_device *dev,
1302			unsigned int action)
1303{
1304	struct ata_port *ap = link->ap;
1305	struct ata_eh_info *ehi = &link->eh_info;
1306	struct ata_eh_context *ehc = &link->eh_context;
1307	unsigned long flags;
1308
1309	trace_ata_eh_about_to_do(link, dev ? dev->devno : 0, action);
1310
1311	spin_lock_irqsave(ap->lock, flags);
1312
1313	ata_eh_clear_action(link, dev, ehi, action);
1314
1315	/* About to take EH action, set RECOVERED.  Ignore actions on
1316	 * slave links as master will do them again.
1317	 */
1318	if (!(ehc->i.flags & ATA_EHI_QUIET) && link != ap->slave_link)
1319		ap->pflags |= ATA_PFLAG_RECOVERED;
1320
1321	spin_unlock_irqrestore(ap->lock, flags);
1322}
1323
1324/**
1325 *	ata_eh_done - EH action complete
1326 *	@link: ATA link for which EH actions are complete
1327 *	@dev: target ATA dev for per-dev action (can be NULL)
1328 *	@action: action just completed
1329 *
1330 *	Called right after performing EH actions to clear related bits
1331 *	in @link->eh_context.
1332 *
1333 *	LOCKING:
1334 *	None.
1335 */
1336void ata_eh_done(struct ata_link *link, struct ata_device *dev,
1337		 unsigned int action)
1338{
1339	struct ata_eh_context *ehc = &link->eh_context;
1340
1341	trace_ata_eh_done(link, dev ? dev->devno : 0, action);
1342
1343	ata_eh_clear_action(link, dev, &ehc->i, action);
1344}
1345
1346/**
1347 *	ata_err_string - convert err_mask to descriptive string
1348 *	@err_mask: error mask to convert to string
1349 *
1350 *	Convert @err_mask to descriptive string.  Errors are
1351 *	prioritized according to severity and only the most severe
1352 *	error is reported.
1353 *
1354 *	LOCKING:
1355 *	None.
1356 *
1357 *	RETURNS:
1358 *	Descriptive string for @err_mask
1359 */
1360static const char *ata_err_string(unsigned int err_mask)
1361{
1362	if (err_mask & AC_ERR_HOST_BUS)
1363		return "host bus error";
1364	if (err_mask & AC_ERR_ATA_BUS)
1365		return "ATA bus error";
1366	if (err_mask & AC_ERR_TIMEOUT)
1367		return "timeout";
1368	if (err_mask & AC_ERR_HSM)
1369		return "HSM violation";
1370	if (err_mask & AC_ERR_SYSTEM)
1371		return "internal error";
1372	if (err_mask & AC_ERR_MEDIA)
1373		return "media error";
1374	if (err_mask & AC_ERR_INVALID)
1375		return "invalid argument";
1376	if (err_mask & AC_ERR_DEV)
1377		return "device error";
1378	if (err_mask & AC_ERR_NCQ)
1379		return "NCQ error";
1380	if (err_mask & AC_ERR_NODEV_HINT)
1381		return "Polling detection error";
1382	return "unknown error";
1383}
1384
1385/**
1386 *	atapi_eh_tur - perform ATAPI TEST_UNIT_READY
1387 *	@dev: target ATAPI device
1388 *	@r_sense_key: out parameter for sense_key
1389 *
1390 *	Perform ATAPI TEST_UNIT_READY.
1391 *
1392 *	LOCKING:
1393 *	EH context (may sleep).
1394 *
1395 *	RETURNS:
1396 *	0 on success, AC_ERR_* mask on failure.
1397 */
1398unsigned int atapi_eh_tur(struct ata_device *dev, u8 *r_sense_key)
1399{
1400	u8 cdb[ATAPI_CDB_LEN] = { TEST_UNIT_READY, 0, 0, 0, 0, 0 };
1401	struct ata_taskfile tf;
1402	unsigned int err_mask;
1403
1404	ata_tf_init(dev, &tf);
1405
1406	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1407	tf.command = ATA_CMD_PACKET;
1408	tf.protocol = ATAPI_PROT_NODATA;
1409
1410	err_mask = ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
1411	if (err_mask == AC_ERR_DEV)
1412		*r_sense_key = tf.error >> 4;
1413	return err_mask;
1414}
1415
1416/**
1417 *	ata_eh_decide_disposition - Disposition a qc based on sense data
1418 *	@qc: qc to examine
1419 *
1420 *	For a regular SCSI command, the SCSI completion callback (scsi_done())
1421 *	will call scsi_complete(), which will call scsi_decide_disposition(),
1422 *	which will call scsi_check_sense(). scsi_complete() finally calls
1423 *	scsi_finish_command(). This is fine for SCSI, since any eventual sense
1424 *	data is usually returned in the completion itself (without invoking SCSI
1425 *	EH). However, for a QC, we always need to fetch the sense data
1426 *	explicitly using SCSI EH.
1427 *
1428 *	A command that is completed via SCSI EH will instead be completed using
1429 *	scsi_eh_flush_done_q(), which will call scsi_finish_command() directly
1430 *	(without ever calling scsi_check_sense()).
1431 *
1432 *	For a command that went through SCSI EH, it is the responsibility of the
1433 *	SCSI EH strategy handler to call scsi_decide_disposition(), see e.g. how
1434 *	scsi_eh_get_sense() calls scsi_decide_disposition() for SCSI LLDDs that
1435 *	do not get the sense data as part of the completion.
1436 *
1437 *	Thus, for QC commands that went via SCSI EH, we need to call
1438 *	scsi_check_sense() ourselves, similar to how scsi_eh_get_sense() calls
1439 *	scsi_decide_disposition(), which calls scsi_check_sense(), in order to
1440 *	set the correct SCSI ML byte (if any).
1441 *
1442 *	LOCKING:
1443 *	EH context.
1444 *
1445 *	RETURNS:
1446 *	SUCCESS or FAILED or NEEDS_RETRY or ADD_TO_MLQUEUE
1447 */
1448enum scsi_disposition ata_eh_decide_disposition(struct ata_queued_cmd *qc)
1449{
1450	return scsi_check_sense(qc->scsicmd);
1451}
1452
1453/**
1454 *	ata_eh_request_sense - perform REQUEST_SENSE_DATA_EXT
1455 *	@qc: qc to perform REQUEST_SENSE_SENSE_DATA_EXT to
 
1456 *
1457 *	Perform REQUEST_SENSE_DATA_EXT after the device reported CHECK
1458 *	SENSE.  This function is an EH helper.
1459 *
1460 *	LOCKING:
1461 *	Kernel thread context (may sleep).
1462 *
1463 *	RETURNS:
1464 *	true if sense data could be fetched, false otherwise.
1465 */
1466static bool ata_eh_request_sense(struct ata_queued_cmd *qc)
 
1467{
1468	struct scsi_cmnd *cmd = qc->scsicmd;
1469	struct ata_device *dev = qc->dev;
1470	struct ata_taskfile tf;
1471	unsigned int err_mask;
1472
1473	if (ata_port_is_frozen(qc->ap)) {
1474		ata_dev_warn(dev, "sense data available but port frozen\n");
1475		return false;
1476	}
1477
 
 
 
1478	if (!ata_id_sense_reporting_enabled(dev->id)) {
1479		ata_dev_warn(qc->dev, "sense data reporting disabled\n");
1480		return false;
1481	}
1482
 
 
1483	ata_tf_init(dev, &tf);
1484	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1485	tf.flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
1486	tf.command = ATA_CMD_REQ_SENSE_DATA;
1487	tf.protocol = ATA_PROT_NODATA;
1488
1489	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1490	/* Ignore err_mask; ATA_ERR might be set */
1491	if (tf.status & ATA_SENSE) {
1492		if (ata_scsi_sense_is_valid(tf.lbah, tf.lbam, tf.lbal)) {
1493			/* Set sense without also setting scsicmd->result */
1494			scsi_build_sense_buffer(dev->flags & ATA_DFLAG_D_SENSE,
1495						cmd->sense_buffer, tf.lbah,
1496						tf.lbam, tf.lbal);
1497			qc->flags |= ATA_QCFLAG_SENSE_VALID;
1498			return true;
1499		}
1500	} else {
1501		ata_dev_warn(dev, "request sense failed stat %02x emask %x\n",
1502			     tf.status, err_mask);
1503	}
1504
1505	return false;
1506}
1507
1508/**
1509 *	atapi_eh_request_sense - perform ATAPI REQUEST_SENSE
1510 *	@dev: device to perform REQUEST_SENSE to
1511 *	@sense_buf: result sense data buffer (SCSI_SENSE_BUFFERSIZE bytes long)
1512 *	@dfl_sense_key: default sense key to use
1513 *
1514 *	Perform ATAPI REQUEST_SENSE after the device reported CHECK
1515 *	SENSE.  This function is EH helper.
1516 *
1517 *	LOCKING:
1518 *	Kernel thread context (may sleep).
1519 *
1520 *	RETURNS:
1521 *	0 on success, AC_ERR_* mask on failure
1522 */
1523unsigned int atapi_eh_request_sense(struct ata_device *dev,
1524					   u8 *sense_buf, u8 dfl_sense_key)
1525{
1526	u8 cdb[ATAPI_CDB_LEN] =
1527		{ REQUEST_SENSE, 0, 0, 0, SCSI_SENSE_BUFFERSIZE, 0 };
1528	struct ata_port *ap = dev->link->ap;
1529	struct ata_taskfile tf;
1530
 
 
1531	memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
1532
1533	/* initialize sense_buf with the error register,
1534	 * for the case where they are -not- overwritten
1535	 */
1536	sense_buf[0] = 0x70;
1537	sense_buf[2] = dfl_sense_key;
1538
1539	/* some devices time out if garbage left in tf */
1540	ata_tf_init(dev, &tf);
1541
1542	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1543	tf.command = ATA_CMD_PACKET;
1544
1545	/* is it pointless to prefer PIO for "safety reasons"? */
1546	if (ap->flags & ATA_FLAG_PIO_DMA) {
1547		tf.protocol = ATAPI_PROT_DMA;
1548		tf.feature |= ATAPI_PKT_DMA;
1549	} else {
1550		tf.protocol = ATAPI_PROT_PIO;
1551		tf.lbam = SCSI_SENSE_BUFFERSIZE;
1552		tf.lbah = 0;
1553	}
1554
1555	return ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
1556				 sense_buf, SCSI_SENSE_BUFFERSIZE, 0);
1557}
1558
1559/**
1560 *	ata_eh_analyze_serror - analyze SError for a failed port
1561 *	@link: ATA link to analyze SError for
1562 *
1563 *	Analyze SError if available and further determine cause of
1564 *	failure.
1565 *
1566 *	LOCKING:
1567 *	None.
1568 */
1569static void ata_eh_analyze_serror(struct ata_link *link)
1570{
1571	struct ata_eh_context *ehc = &link->eh_context;
1572	u32 serror = ehc->i.serror;
1573	unsigned int err_mask = 0, action = 0;
1574	u32 hotplug_mask;
1575
1576	if (serror & (SERR_PERSISTENT | SERR_DATA)) {
1577		err_mask |= AC_ERR_ATA_BUS;
1578		action |= ATA_EH_RESET;
1579	}
1580	if (serror & SERR_PROTOCOL) {
1581		err_mask |= AC_ERR_HSM;
1582		action |= ATA_EH_RESET;
1583	}
1584	if (serror & SERR_INTERNAL) {
1585		err_mask |= AC_ERR_SYSTEM;
1586		action |= ATA_EH_RESET;
1587	}
1588
1589	/* Determine whether a hotplug event has occurred.  Both
1590	 * SError.N/X are considered hotplug events for enabled or
1591	 * host links.  For disabled PMP links, only N bit is
1592	 * considered as X bit is left at 1 for link plugging.
1593	 */
1594	if (link->lpm_policy > ATA_LPM_MAX_POWER)
1595		hotplug_mask = 0;	/* hotplug doesn't work w/ LPM */
1596	else if (!(link->flags & ATA_LFLAG_DISABLED) || ata_is_host_link(link))
1597		hotplug_mask = SERR_PHYRDY_CHG | SERR_DEV_XCHG;
1598	else
1599		hotplug_mask = SERR_PHYRDY_CHG;
1600
1601	if (serror & hotplug_mask)
1602		ata_ehi_hotplugged(&ehc->i);
1603
1604	ehc->i.err_mask |= err_mask;
1605	ehc->i.action |= action;
1606}
1607
1608/**
1609 *	ata_eh_analyze_tf - analyze taskfile of a failed qc
1610 *	@qc: qc to analyze
 
1611 *
1612 *	Analyze taskfile of @qc and further determine cause of
1613 *	failure.  This function also requests ATAPI sense data if
1614 *	available.
1615 *
1616 *	LOCKING:
1617 *	Kernel thread context (may sleep).
1618 *
1619 *	RETURNS:
1620 *	Determined recovery action
1621 */
1622static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc)
 
1623{
1624	const struct ata_taskfile *tf = &qc->result_tf;
1625	unsigned int tmp, action = 0;
1626	u8 stat = tf->status, err = tf->error;
1627
1628	if ((stat & (ATA_BUSY | ATA_DRQ | ATA_DRDY)) != ATA_DRDY) {
1629		qc->err_mask |= AC_ERR_HSM;
1630		return ATA_EH_RESET;
1631	}
1632
1633	if (stat & (ATA_ERR | ATA_DF)) {
1634		qc->err_mask |= AC_ERR_DEV;
1635		/*
1636		 * Sense data reporting does not work if the
1637		 * device fault bit is set.
1638		 */
1639		if (stat & ATA_DF)
1640			stat &= ~ATA_SENSE;
1641	} else {
1642		return 0;
1643	}
1644
1645	switch (qc->dev->class) {
 
 
 
 
1646	case ATA_DEV_ATA:
1647	case ATA_DEV_ZAC:
1648		/*
1649		 * Fetch the sense data explicitly if:
1650		 * -It was a non-NCQ command that failed, or
1651		 * -It was a NCQ command that failed, but the sense data
1652		 *  was not included in the NCQ command error log
1653		 *  (i.e. NCQ autosense is not supported by the device).
1654		 */
1655		if (!(qc->flags & ATA_QCFLAG_SENSE_VALID) &&
1656		    (stat & ATA_SENSE) && ata_eh_request_sense(qc))
1657			set_status_byte(qc->scsicmd, SAM_STAT_CHECK_CONDITION);
1658		if (err & ATA_ICRC)
1659			qc->err_mask |= AC_ERR_ATA_BUS;
1660		if (err & (ATA_UNC | ATA_AMNF))
1661			qc->err_mask |= AC_ERR_MEDIA;
1662		if (err & ATA_IDNF)
1663			qc->err_mask |= AC_ERR_INVALID;
1664		break;
1665
1666	case ATA_DEV_ATAPI:
1667		if (!ata_port_is_frozen(qc->ap)) {
1668			tmp = atapi_eh_request_sense(qc->dev,
1669						qc->scsicmd->sense_buffer,
1670						qc->result_tf.error >> 4);
1671			if (!tmp)
1672				qc->flags |= ATA_QCFLAG_SENSE_VALID;
1673			else
1674				qc->err_mask |= tmp;
1675		}
1676	}
1677
1678	if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
1679		enum scsi_disposition ret = ata_eh_decide_disposition(qc);
1680
1681		/*
1682		 * SUCCESS here means that the sense code could be
1683		 * evaluated and should be passed to the upper layers
1684		 * for correct evaluation.
1685		 * FAILED means the sense code could not be interpreted
1686		 * and the device would need to be reset.
1687		 * NEEDS_RETRY and ADD_TO_MLQUEUE means that the
1688		 * command would need to be retried.
1689		 */
1690		if (ret == NEEDS_RETRY || ret == ADD_TO_MLQUEUE) {
1691			qc->flags |= ATA_QCFLAG_RETRY;
1692			qc->err_mask |= AC_ERR_OTHER;
1693		} else if (ret != SUCCESS) {
1694			qc->err_mask |= AC_ERR_HSM;
1695		}
1696	}
1697	if (qc->err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT | AC_ERR_ATA_BUS))
1698		action |= ATA_EH_RESET;
1699
1700	return action;
1701}
1702
1703static int ata_eh_categorize_error(unsigned int eflags, unsigned int err_mask,
1704				   int *xfer_ok)
1705{
1706	int base = 0;
1707
1708	if (!(eflags & ATA_EFLAG_DUBIOUS_XFER))
1709		*xfer_ok = 1;
1710
1711	if (!*xfer_ok)
1712		base = ATA_ECAT_DUBIOUS_NONE;
1713
1714	if (err_mask & AC_ERR_ATA_BUS)
1715		return base + ATA_ECAT_ATA_BUS;
1716
1717	if (err_mask & AC_ERR_TIMEOUT)
1718		return base + ATA_ECAT_TOUT_HSM;
1719
1720	if (eflags & ATA_EFLAG_IS_IO) {
1721		if (err_mask & AC_ERR_HSM)
1722			return base + ATA_ECAT_TOUT_HSM;
1723		if ((err_mask &
1724		     (AC_ERR_DEV|AC_ERR_MEDIA|AC_ERR_INVALID)) == AC_ERR_DEV)
1725			return base + ATA_ECAT_UNK_DEV;
1726	}
1727
1728	return 0;
1729}
1730
1731struct speed_down_verdict_arg {
1732	u64 since;
1733	int xfer_ok;
1734	int nr_errors[ATA_ECAT_NR];
1735};
1736
1737static int speed_down_verdict_cb(struct ata_ering_entry *ent, void *void_arg)
1738{
1739	struct speed_down_verdict_arg *arg = void_arg;
1740	int cat;
1741
1742	if ((ent->eflags & ATA_EFLAG_OLD_ER) || (ent->timestamp < arg->since))
1743		return -1;
1744
1745	cat = ata_eh_categorize_error(ent->eflags, ent->err_mask,
1746				      &arg->xfer_ok);
1747	arg->nr_errors[cat]++;
1748
1749	return 0;
1750}
1751
1752/**
1753 *	ata_eh_speed_down_verdict - Determine speed down verdict
1754 *	@dev: Device of interest
1755 *
1756 *	This function examines error ring of @dev and determines
1757 *	whether NCQ needs to be turned off, transfer speed should be
1758 *	stepped down, or falling back to PIO is necessary.
1759 *
1760 *	ECAT_ATA_BUS	: ATA_BUS error for any command
1761 *
1762 *	ECAT_TOUT_HSM	: TIMEOUT for any command or HSM violation for
1763 *			  IO commands
1764 *
1765 *	ECAT_UNK_DEV	: Unknown DEV error for IO commands
1766 *
1767 *	ECAT_DUBIOUS_*	: Identical to above three but occurred while
1768 *			  data transfer hasn't been verified.
1769 *
1770 *	Verdicts are
1771 *
1772 *	NCQ_OFF		: Turn off NCQ.
1773 *
1774 *	SPEED_DOWN	: Speed down transfer speed but don't fall back
1775 *			  to PIO.
1776 *
1777 *	FALLBACK_TO_PIO	: Fall back to PIO.
1778 *
1779 *	Even if multiple verdicts are returned, only one action is
1780 *	taken per error.  An action triggered by non-DUBIOUS errors
1781 *	clears ering, while one triggered by DUBIOUS_* errors doesn't.
1782 *	This is to expedite speed down decisions right after device is
1783 *	initially configured.
1784 *
1785 *	The following are speed down rules.  #1 and #2 deal with
1786 *	DUBIOUS errors.
1787 *
1788 *	1. If more than one DUBIOUS_ATA_BUS or DUBIOUS_TOUT_HSM errors
1789 *	   occurred during last 5 mins, SPEED_DOWN and FALLBACK_TO_PIO.
1790 *
1791 *	2. If more than one DUBIOUS_TOUT_HSM or DUBIOUS_UNK_DEV errors
1792 *	   occurred during last 5 mins, NCQ_OFF.
1793 *
1794 *	3. If more than 8 ATA_BUS, TOUT_HSM or UNK_DEV errors
1795 *	   occurred during last 5 mins, FALLBACK_TO_PIO
1796 *
1797 *	4. If more than 3 TOUT_HSM or UNK_DEV errors occurred
1798 *	   during last 10 mins, NCQ_OFF.
1799 *
1800 *	5. If more than 3 ATA_BUS or TOUT_HSM errors, or more than 6
1801 *	   UNK_DEV errors occurred during last 10 mins, SPEED_DOWN.
1802 *
1803 *	LOCKING:
1804 *	Inherited from caller.
1805 *
1806 *	RETURNS:
1807 *	OR of ATA_EH_SPDN_* flags.
1808 */
1809static unsigned int ata_eh_speed_down_verdict(struct ata_device *dev)
1810{
1811	const u64 j5mins = 5LLU * 60 * HZ, j10mins = 10LLU * 60 * HZ;
1812	u64 j64 = get_jiffies_64();
1813	struct speed_down_verdict_arg arg;
1814	unsigned int verdict = 0;
1815
1816	/* scan past 5 mins of error history */
1817	memset(&arg, 0, sizeof(arg));
1818	arg.since = j64 - min(j64, j5mins);
1819	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1820
1821	if (arg.nr_errors[ATA_ECAT_DUBIOUS_ATA_BUS] +
1822	    arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] > 1)
1823		verdict |= ATA_EH_SPDN_SPEED_DOWN |
1824			ATA_EH_SPDN_FALLBACK_TO_PIO | ATA_EH_SPDN_KEEP_ERRORS;
1825
1826	if (arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] +
1827	    arg.nr_errors[ATA_ECAT_DUBIOUS_UNK_DEV] > 1)
1828		verdict |= ATA_EH_SPDN_NCQ_OFF | ATA_EH_SPDN_KEEP_ERRORS;
1829
1830	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1831	    arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1832	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1833		verdict |= ATA_EH_SPDN_FALLBACK_TO_PIO;
1834
1835	/* scan past 10 mins of error history */
1836	memset(&arg, 0, sizeof(arg));
1837	arg.since = j64 - min(j64, j10mins);
1838	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1839
1840	if (arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1841	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 3)
1842		verdict |= ATA_EH_SPDN_NCQ_OFF;
1843
1844	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1845	    arg.nr_errors[ATA_ECAT_TOUT_HSM] > 3 ||
1846	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1847		verdict |= ATA_EH_SPDN_SPEED_DOWN;
1848
1849	return verdict;
1850}
1851
1852/**
1853 *	ata_eh_speed_down - record error and speed down if necessary
1854 *	@dev: Failed device
1855 *	@eflags: mask of ATA_EFLAG_* flags
1856 *	@err_mask: err_mask of the error
1857 *
1858 *	Record error and examine error history to determine whether
1859 *	adjusting transmission speed is necessary.  It also sets
1860 *	transmission limits appropriately if such adjustment is
1861 *	necessary.
1862 *
1863 *	LOCKING:
1864 *	Kernel thread context (may sleep).
1865 *
1866 *	RETURNS:
1867 *	Determined recovery action.
1868 */
1869static unsigned int ata_eh_speed_down(struct ata_device *dev,
1870				unsigned int eflags, unsigned int err_mask)
1871{
1872	struct ata_link *link = ata_dev_phys_link(dev);
1873	int xfer_ok = 0;
1874	unsigned int verdict;
1875	unsigned int action = 0;
1876
1877	/* don't bother if Cat-0 error */
1878	if (ata_eh_categorize_error(eflags, err_mask, &xfer_ok) == 0)
1879		return 0;
1880
1881	/* record error and determine whether speed down is necessary */
1882	ata_ering_record(&dev->ering, eflags, err_mask);
1883	verdict = ata_eh_speed_down_verdict(dev);
1884
1885	/* turn off NCQ? */
1886	if ((verdict & ATA_EH_SPDN_NCQ_OFF) && ata_ncq_enabled(dev)) {
 
 
1887		dev->flags |= ATA_DFLAG_NCQ_OFF;
1888		ata_dev_warn(dev, "NCQ disabled due to excessive errors\n");
1889		goto done;
1890	}
1891
1892	/* speed down? */
1893	if (verdict & ATA_EH_SPDN_SPEED_DOWN) {
1894		/* speed down SATA link speed if possible */
1895		if (sata_down_spd_limit(link, 0) == 0) {
1896			action |= ATA_EH_RESET;
1897			goto done;
1898		}
1899
1900		/* lower transfer mode */
1901		if (dev->spdn_cnt < 2) {
1902			static const int dma_dnxfer_sel[] =
1903				{ ATA_DNXFER_DMA, ATA_DNXFER_40C };
1904			static const int pio_dnxfer_sel[] =
1905				{ ATA_DNXFER_PIO, ATA_DNXFER_FORCE_PIO0 };
1906			int sel;
1907
1908			if (dev->xfer_shift != ATA_SHIFT_PIO)
1909				sel = dma_dnxfer_sel[dev->spdn_cnt];
1910			else
1911				sel = pio_dnxfer_sel[dev->spdn_cnt];
1912
1913			dev->spdn_cnt++;
1914
1915			if (ata_down_xfermask_limit(dev, sel) == 0) {
1916				action |= ATA_EH_RESET;
1917				goto done;
1918			}
1919		}
1920	}
1921
1922	/* Fall back to PIO?  Slowing down to PIO is meaningless for
1923	 * SATA ATA devices.  Consider it only for PATA and SATAPI.
1924	 */
1925	if ((verdict & ATA_EH_SPDN_FALLBACK_TO_PIO) && (dev->spdn_cnt >= 2) &&
1926	    (link->ap->cbl != ATA_CBL_SATA || dev->class == ATA_DEV_ATAPI) &&
1927	    (dev->xfer_shift != ATA_SHIFT_PIO)) {
1928		if (ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO) == 0) {
1929			dev->spdn_cnt = 0;
1930			action |= ATA_EH_RESET;
1931			goto done;
1932		}
1933	}
1934
1935	return 0;
1936 done:
1937	/* device has been slowed down, blow error history */
1938	if (!(verdict & ATA_EH_SPDN_KEEP_ERRORS))
1939		ata_ering_clear(&dev->ering);
1940	return action;
1941}
1942
1943/**
1944 *	ata_eh_worth_retry - analyze error and decide whether to retry
1945 *	@qc: qc to possibly retry
1946 *
1947 *	Look at the cause of the error and decide if a retry
1948 * 	might be useful or not.  We don't want to retry media errors
1949 *	because the drive itself has probably already taken 10-30 seconds
1950 *	doing its own internal retries before reporting the failure.
1951 */
1952static inline int ata_eh_worth_retry(struct ata_queued_cmd *qc)
1953{
1954	if (qc->err_mask & AC_ERR_MEDIA)
1955		return 0;	/* don't retry media errors */
1956	if (qc->flags & ATA_QCFLAG_IO)
1957		return 1;	/* otherwise retry anything from fs stack */
1958	if (qc->err_mask & AC_ERR_INVALID)
1959		return 0;	/* don't retry these */
1960	return qc->err_mask != AC_ERR_DEV;  /* retry if not dev error */
1961}
1962
1963/**
1964 *      ata_eh_quiet - check if we need to be quiet about a command error
1965 *      @qc: qc to check
1966 *
1967 *      Look at the qc flags anbd its scsi command request flags to determine
1968 *      if we need to be quiet about the command failure.
1969 */
1970static inline bool ata_eh_quiet(struct ata_queued_cmd *qc)
1971{
1972	if (qc->scsicmd && scsi_cmd_to_rq(qc->scsicmd)->rq_flags & RQF_QUIET)
 
1973		qc->flags |= ATA_QCFLAG_QUIET;
1974	return qc->flags & ATA_QCFLAG_QUIET;
1975}
1976
1977static int ata_eh_get_non_ncq_success_sense(struct ata_link *link)
1978{
1979	struct ata_port *ap = link->ap;
1980	struct ata_queued_cmd *qc;
1981
1982	qc = __ata_qc_from_tag(ap, link->active_tag);
1983	if (!qc)
1984		return -EIO;
1985
1986	if (!(qc->flags & ATA_QCFLAG_EH) ||
1987	    !(qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD) ||
1988	    qc->err_mask)
1989		return -EIO;
1990
1991	if (!ata_eh_request_sense(qc))
1992		return -EIO;
1993
1994	/*
1995	 * No point in checking the return value, since the command has already
1996	 * completed successfully.
1997	 */
1998	ata_eh_decide_disposition(qc);
1999
2000	return 0;
2001}
2002
2003static void ata_eh_get_success_sense(struct ata_link *link)
2004{
2005	struct ata_eh_context *ehc = &link->eh_context;
2006	struct ata_device *dev = link->device;
2007	struct ata_port *ap = link->ap;
2008	struct ata_queued_cmd *qc;
2009	int tag, ret = 0;
2010
2011	if (!(ehc->i.dev_action[dev->devno] & ATA_EH_GET_SUCCESS_SENSE))
2012		return;
2013
2014	/* if frozen, we can't do much */
2015	if (ata_port_is_frozen(ap)) {
2016		ata_dev_warn(dev,
2017			"successful sense data available but port frozen\n");
2018		goto out;
2019	}
2020
2021	/*
2022	 * If the link has sactive set, then we have outstanding NCQ commands
2023	 * and have to read the Successful NCQ Commands log to get the sense
2024	 * data. Otherwise, we are dealing with a non-NCQ command and use
2025	 * request sense ext command to retrieve the sense data.
2026	 */
2027	if (link->sactive)
2028		ret = ata_eh_get_ncq_success_sense(link);
2029	else
2030		ret = ata_eh_get_non_ncq_success_sense(link);
2031	if (ret)
2032		goto out;
2033
2034	ata_eh_done(link, dev, ATA_EH_GET_SUCCESS_SENSE);
2035	return;
2036
2037out:
2038	/*
2039	 * If we failed to get sense data for a successful command that ought to
2040	 * have sense data, we cannot simply return BLK_STS_OK to user space.
2041	 * This is because we can't know if the sense data that we couldn't get
2042	 * was actually "DATA CURRENTLY UNAVAILABLE". Reporting such a command
2043	 * as success to user space would result in a silent data corruption.
2044	 * Thus, add a bogus ABORTED_COMMAND sense data to such commands, such
2045	 * that SCSI will report these commands as BLK_STS_IOERR to user space.
2046	 */
2047	ata_qc_for_each_raw(ap, qc, tag) {
2048		if (!(qc->flags & ATA_QCFLAG_EH) ||
2049		    !(qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD) ||
2050		    qc->err_mask ||
2051		    ata_dev_phys_link(qc->dev) != link)
2052			continue;
2053
2054		/* We managed to get sense for this success command, skip. */
2055		if (qc->flags & ATA_QCFLAG_SENSE_VALID)
2056			continue;
2057
2058		/* This success command did not have any sense data, skip. */
2059		if (!(qc->result_tf.status & ATA_SENSE))
2060			continue;
2061
2062		/* This success command had sense data, but we failed to get. */
2063		ata_scsi_set_sense(dev, qc->scsicmd, ABORTED_COMMAND, 0, 0);
2064		qc->flags |= ATA_QCFLAG_SENSE_VALID;
2065	}
2066	ata_eh_done(link, dev, ATA_EH_GET_SUCCESS_SENSE);
2067}
2068
2069/**
2070 *	ata_eh_link_autopsy - analyze error and determine recovery action
2071 *	@link: host link to perform autopsy on
2072 *
2073 *	Analyze why @link failed and determine which recovery actions
2074 *	are needed.  This function also sets more detailed AC_ERR_*
2075 *	values and fills sense data for ATAPI CHECK SENSE.
2076 *
2077 *	LOCKING:
2078 *	Kernel thread context (may sleep).
2079 */
2080static void ata_eh_link_autopsy(struct ata_link *link)
2081{
2082	struct ata_port *ap = link->ap;
2083	struct ata_eh_context *ehc = &link->eh_context;
2084	struct ata_queued_cmd *qc;
2085	struct ata_device *dev;
2086	unsigned int all_err_mask = 0, eflags = 0;
2087	int tag, nr_failed = 0, nr_quiet = 0;
2088	u32 serror;
2089	int rc;
2090
 
 
2091	if (ehc->i.flags & ATA_EHI_NO_AUTOPSY)
2092		return;
2093
2094	/* obtain and analyze SError */
2095	rc = sata_scr_read(link, SCR_ERROR, &serror);
2096	if (rc == 0) {
2097		ehc->i.serror |= serror;
2098		ata_eh_analyze_serror(link);
2099	} else if (rc != -EOPNOTSUPP) {
2100		/* SError read failed, force reset and probing */
2101		ehc->i.probe_mask |= ATA_ALL_DEVICES;
2102		ehc->i.action |= ATA_EH_RESET;
2103		ehc->i.err_mask |= AC_ERR_OTHER;
2104	}
2105
2106	/* analyze NCQ failure */
2107	ata_eh_analyze_ncq_error(link);
2108
2109	/*
2110	 * Check if this was a successful command that simply needs sense data.
2111	 * Since the sense data is not part of the completion, we need to fetch
2112	 * it using an additional command. Since this can't be done from irq
2113	 * context, the sense data for successful commands are fetched by EH.
2114	 */
2115	ata_eh_get_success_sense(link);
2116
2117	/* any real error trumps AC_ERR_OTHER */
2118	if (ehc->i.err_mask & ~AC_ERR_OTHER)
2119		ehc->i.err_mask &= ~AC_ERR_OTHER;
2120
2121	all_err_mask |= ehc->i.err_mask;
2122
2123	ata_qc_for_each_raw(ap, qc, tag) {
2124		if (!(qc->flags & ATA_QCFLAG_EH) ||
2125		    qc->flags & ATA_QCFLAG_RETRY ||
2126		    qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD ||
2127		    ata_dev_phys_link(qc->dev) != link)
2128			continue;
2129
2130		/* inherit upper level err_mask */
2131		qc->err_mask |= ehc->i.err_mask;
2132
2133		/* analyze TF */
2134		ehc->i.action |= ata_eh_analyze_tf(qc);
2135
2136		/* DEV errors are probably spurious in case of ATA_BUS error */
2137		if (qc->err_mask & AC_ERR_ATA_BUS)
2138			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_MEDIA |
2139					  AC_ERR_INVALID);
2140
2141		/* any real error trumps unknown error */
2142		if (qc->err_mask & ~AC_ERR_OTHER)
2143			qc->err_mask &= ~AC_ERR_OTHER;
2144
2145		/*
2146		 * SENSE_VALID trumps dev/unknown error and revalidation. Upper
2147		 * layers will determine whether the command is worth retrying
2148		 * based on the sense data and device class/type. Otherwise,
2149		 * determine directly if the command is worth retrying using its
2150		 * error mask and flags.
2151		 */
2152		if (qc->flags & ATA_QCFLAG_SENSE_VALID)
2153			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_OTHER);
2154		else if (ata_eh_worth_retry(qc))
2155			qc->flags |= ATA_QCFLAG_RETRY;
2156
2157		/* accumulate error info */
2158		ehc->i.dev = qc->dev;
2159		all_err_mask |= qc->err_mask;
2160		if (qc->flags & ATA_QCFLAG_IO)
2161			eflags |= ATA_EFLAG_IS_IO;
2162		trace_ata_eh_link_autopsy_qc(qc);
2163
2164		/* Count quiet errors */
2165		if (ata_eh_quiet(qc))
2166			nr_quiet++;
2167		nr_failed++;
2168	}
2169
2170	/* If all failed commands requested silence, then be quiet */
2171	if (nr_quiet == nr_failed)
2172		ehc->i.flags |= ATA_EHI_QUIET;
2173
2174	/* enforce default EH actions */
2175	if (ata_port_is_frozen(ap) ||
2176	    all_err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT))
2177		ehc->i.action |= ATA_EH_RESET;
2178	else if (((eflags & ATA_EFLAG_IS_IO) && all_err_mask) ||
2179		 (!(eflags & ATA_EFLAG_IS_IO) && (all_err_mask & ~AC_ERR_DEV)))
2180		ehc->i.action |= ATA_EH_REVALIDATE;
2181
2182	/* If we have offending qcs and the associated failed device,
2183	 * perform per-dev EH action only on the offending device.
2184	 */
2185	if (ehc->i.dev) {
2186		ehc->i.dev_action[ehc->i.dev->devno] |=
2187			ehc->i.action & ATA_EH_PERDEV_MASK;
2188		ehc->i.action &= ~ATA_EH_PERDEV_MASK;
2189	}
2190
2191	/* propagate timeout to host link */
2192	if ((all_err_mask & AC_ERR_TIMEOUT) && !ata_is_host_link(link))
2193		ap->link.eh_context.i.err_mask |= AC_ERR_TIMEOUT;
2194
2195	/* record error and consider speeding down */
2196	dev = ehc->i.dev;
2197	if (!dev && ((ata_link_max_devices(link) == 1 &&
2198		      ata_dev_enabled(link->device))))
2199	    dev = link->device;
2200
2201	if (dev) {
2202		if (dev->flags & ATA_DFLAG_DUBIOUS_XFER)
2203			eflags |= ATA_EFLAG_DUBIOUS_XFER;
2204		ehc->i.action |= ata_eh_speed_down(dev, eflags, all_err_mask);
2205		trace_ata_eh_link_autopsy(dev, ehc->i.action, all_err_mask);
2206	}
 
2207}
2208
2209/**
2210 *	ata_eh_autopsy - analyze error and determine recovery action
2211 *	@ap: host port to perform autopsy on
2212 *
2213 *	Analyze all links of @ap and determine why they failed and
2214 *	which recovery actions are needed.
2215 *
2216 *	LOCKING:
2217 *	Kernel thread context (may sleep).
2218 */
2219void ata_eh_autopsy(struct ata_port *ap)
2220{
2221	struct ata_link *link;
2222
2223	ata_for_each_link(link, ap, EDGE)
2224		ata_eh_link_autopsy(link);
2225
2226	/* Handle the frigging slave link.  Autopsy is done similarly
2227	 * but actions and flags are transferred over to the master
2228	 * link and handled from there.
2229	 */
2230	if (ap->slave_link) {
2231		struct ata_eh_context *mehc = &ap->link.eh_context;
2232		struct ata_eh_context *sehc = &ap->slave_link->eh_context;
2233
2234		/* transfer control flags from master to slave */
2235		sehc->i.flags |= mehc->i.flags & ATA_EHI_TO_SLAVE_MASK;
2236
2237		/* perform autopsy on the slave link */
2238		ata_eh_link_autopsy(ap->slave_link);
2239
2240		/* transfer actions from slave to master and clear slave */
2241		ata_eh_about_to_do(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2242		mehc->i.action		|= sehc->i.action;
2243		mehc->i.dev_action[1]	|= sehc->i.dev_action[1];
2244		mehc->i.flags		|= sehc->i.flags;
2245		ata_eh_done(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2246	}
2247
2248	/* Autopsy of fanout ports can affect host link autopsy.
2249	 * Perform host link autopsy last.
2250	 */
2251	if (sata_pmp_attached(ap))
2252		ata_eh_link_autopsy(&ap->link);
2253}
2254
2255/**
2256 *	ata_get_cmd_name - get name for ATA command
2257 *	@command: ATA command code to get name for
2258 *
2259 *	Return a textual name of the given command or "unknown"
 
2260 *
2261 *	LOCKING:
2262 *	None
2263 */
2264const char *ata_get_cmd_name(u8 command)
2265{
2266#ifdef CONFIG_ATA_VERBOSE_ERROR
2267	static const struct
2268	{
2269		u8 command;
2270		const char *text;
2271	} cmd_descr[] = {
2272		{ ATA_CMD_DEV_RESET,		"DEVICE RESET" },
2273		{ ATA_CMD_CHK_POWER,		"CHECK POWER MODE" },
2274		{ ATA_CMD_STANDBY,		"STANDBY" },
2275		{ ATA_CMD_IDLE,			"IDLE" },
2276		{ ATA_CMD_EDD,			"EXECUTE DEVICE DIAGNOSTIC" },
2277		{ ATA_CMD_DOWNLOAD_MICRO,	"DOWNLOAD MICROCODE" },
2278		{ ATA_CMD_DOWNLOAD_MICRO_DMA,	"DOWNLOAD MICROCODE DMA" },
2279		{ ATA_CMD_NOP,			"NOP" },
2280		{ ATA_CMD_FLUSH,		"FLUSH CACHE" },
2281		{ ATA_CMD_FLUSH_EXT,		"FLUSH CACHE EXT" },
2282		{ ATA_CMD_ID_ATA,		"IDENTIFY DEVICE" },
2283		{ ATA_CMD_ID_ATAPI,		"IDENTIFY PACKET DEVICE" },
2284		{ ATA_CMD_SERVICE,		"SERVICE" },
2285		{ ATA_CMD_READ,			"READ DMA" },
2286		{ ATA_CMD_READ_EXT,		"READ DMA EXT" },
2287		{ ATA_CMD_READ_QUEUED,		"READ DMA QUEUED" },
2288		{ ATA_CMD_READ_STREAM_EXT,	"READ STREAM EXT" },
2289		{ ATA_CMD_READ_STREAM_DMA_EXT,  "READ STREAM DMA EXT" },
2290		{ ATA_CMD_WRITE,		"WRITE DMA" },
2291		{ ATA_CMD_WRITE_EXT,		"WRITE DMA EXT" },
2292		{ ATA_CMD_WRITE_QUEUED,		"WRITE DMA QUEUED EXT" },
2293		{ ATA_CMD_WRITE_STREAM_EXT,	"WRITE STREAM EXT" },
2294		{ ATA_CMD_WRITE_STREAM_DMA_EXT, "WRITE STREAM DMA EXT" },
2295		{ ATA_CMD_WRITE_FUA_EXT,	"WRITE DMA FUA EXT" },
2296		{ ATA_CMD_WRITE_QUEUED_FUA_EXT, "WRITE DMA QUEUED FUA EXT" },
2297		{ ATA_CMD_FPDMA_READ,		"READ FPDMA QUEUED" },
2298		{ ATA_CMD_FPDMA_WRITE,		"WRITE FPDMA QUEUED" },
2299		{ ATA_CMD_NCQ_NON_DATA,		"NCQ NON-DATA" },
2300		{ ATA_CMD_FPDMA_SEND,		"SEND FPDMA QUEUED" },
2301		{ ATA_CMD_FPDMA_RECV,		"RECEIVE FPDMA QUEUED" },
2302		{ ATA_CMD_PIO_READ,		"READ SECTOR(S)" },
2303		{ ATA_CMD_PIO_READ_EXT,		"READ SECTOR(S) EXT" },
2304		{ ATA_CMD_PIO_WRITE,		"WRITE SECTOR(S)" },
2305		{ ATA_CMD_PIO_WRITE_EXT,	"WRITE SECTOR(S) EXT" },
2306		{ ATA_CMD_READ_MULTI,		"READ MULTIPLE" },
2307		{ ATA_CMD_READ_MULTI_EXT,	"READ MULTIPLE EXT" },
2308		{ ATA_CMD_WRITE_MULTI,		"WRITE MULTIPLE" },
2309		{ ATA_CMD_WRITE_MULTI_EXT,	"WRITE MULTIPLE EXT" },
2310		{ ATA_CMD_WRITE_MULTI_FUA_EXT,	"WRITE MULTIPLE FUA EXT" },
2311		{ ATA_CMD_SET_FEATURES,		"SET FEATURES" },
2312		{ ATA_CMD_SET_MULTI,		"SET MULTIPLE MODE" },
2313		{ ATA_CMD_VERIFY,		"READ VERIFY SECTOR(S)" },
2314		{ ATA_CMD_VERIFY_EXT,		"READ VERIFY SECTOR(S) EXT" },
2315		{ ATA_CMD_WRITE_UNCORR_EXT,	"WRITE UNCORRECTABLE EXT" },
2316		{ ATA_CMD_STANDBYNOW1,		"STANDBY IMMEDIATE" },
2317		{ ATA_CMD_IDLEIMMEDIATE,	"IDLE IMMEDIATE" },
2318		{ ATA_CMD_SLEEP,		"SLEEP" },
2319		{ ATA_CMD_INIT_DEV_PARAMS,	"INITIALIZE DEVICE PARAMETERS" },
2320		{ ATA_CMD_READ_NATIVE_MAX,	"READ NATIVE MAX ADDRESS" },
2321		{ ATA_CMD_READ_NATIVE_MAX_EXT,	"READ NATIVE MAX ADDRESS EXT" },
2322		{ ATA_CMD_SET_MAX,		"SET MAX ADDRESS" },
2323		{ ATA_CMD_SET_MAX_EXT,		"SET MAX ADDRESS EXT" },
2324		{ ATA_CMD_READ_LOG_EXT,		"READ LOG EXT" },
2325		{ ATA_CMD_WRITE_LOG_EXT,	"WRITE LOG EXT" },
2326		{ ATA_CMD_READ_LOG_DMA_EXT,	"READ LOG DMA EXT" },
2327		{ ATA_CMD_WRITE_LOG_DMA_EXT,	"WRITE LOG DMA EXT" },
2328		{ ATA_CMD_TRUSTED_NONDATA,	"TRUSTED NON-DATA" },
2329		{ ATA_CMD_TRUSTED_RCV,		"TRUSTED RECEIVE" },
2330		{ ATA_CMD_TRUSTED_RCV_DMA,	"TRUSTED RECEIVE DMA" },
2331		{ ATA_CMD_TRUSTED_SND,		"TRUSTED SEND" },
2332		{ ATA_CMD_TRUSTED_SND_DMA,	"TRUSTED SEND DMA" },
2333		{ ATA_CMD_PMP_READ,		"READ BUFFER" },
2334		{ ATA_CMD_PMP_READ_DMA,		"READ BUFFER DMA" },
2335		{ ATA_CMD_PMP_WRITE,		"WRITE BUFFER" },
2336		{ ATA_CMD_PMP_WRITE_DMA,	"WRITE BUFFER DMA" },
2337		{ ATA_CMD_CONF_OVERLAY,		"DEVICE CONFIGURATION OVERLAY" },
2338		{ ATA_CMD_SEC_SET_PASS,		"SECURITY SET PASSWORD" },
2339		{ ATA_CMD_SEC_UNLOCK,		"SECURITY UNLOCK" },
2340		{ ATA_CMD_SEC_ERASE_PREP,	"SECURITY ERASE PREPARE" },
2341		{ ATA_CMD_SEC_ERASE_UNIT,	"SECURITY ERASE UNIT" },
2342		{ ATA_CMD_SEC_FREEZE_LOCK,	"SECURITY FREEZE LOCK" },
2343		{ ATA_CMD_SEC_DISABLE_PASS,	"SECURITY DISABLE PASSWORD" },
2344		{ ATA_CMD_CONFIG_STREAM,	"CONFIGURE STREAM" },
2345		{ ATA_CMD_SMART,		"SMART" },
2346		{ ATA_CMD_MEDIA_LOCK,		"DOOR LOCK" },
2347		{ ATA_CMD_MEDIA_UNLOCK,		"DOOR UNLOCK" },
2348		{ ATA_CMD_DSM,			"DATA SET MANAGEMENT" },
2349		{ ATA_CMD_CHK_MED_CRD_TYP,	"CHECK MEDIA CARD TYPE" },
2350		{ ATA_CMD_CFA_REQ_EXT_ERR,	"CFA REQUEST EXTENDED ERROR" },
2351		{ ATA_CMD_CFA_WRITE_NE,		"CFA WRITE SECTORS WITHOUT ERASE" },
2352		{ ATA_CMD_CFA_TRANS_SECT,	"CFA TRANSLATE SECTOR" },
2353		{ ATA_CMD_CFA_ERASE,		"CFA ERASE SECTORS" },
2354		{ ATA_CMD_CFA_WRITE_MULT_NE,	"CFA WRITE MULTIPLE WITHOUT ERASE" },
2355		{ ATA_CMD_REQ_SENSE_DATA,	"REQUEST SENSE DATA EXT" },
2356		{ ATA_CMD_SANITIZE_DEVICE,	"SANITIZE DEVICE" },
2357		{ ATA_CMD_ZAC_MGMT_IN,		"ZAC MANAGEMENT IN" },
2358		{ ATA_CMD_ZAC_MGMT_OUT,		"ZAC MANAGEMENT OUT" },
2359		{ ATA_CMD_READ_LONG,		"READ LONG (with retries)" },
2360		{ ATA_CMD_READ_LONG_ONCE,	"READ LONG (without retries)" },
2361		{ ATA_CMD_WRITE_LONG,		"WRITE LONG (with retries)" },
2362		{ ATA_CMD_WRITE_LONG_ONCE,	"WRITE LONG (without retries)" },
2363		{ ATA_CMD_RESTORE,		"RECALIBRATE" },
2364		{ 0,				NULL } /* terminate list */
2365	};
2366
2367	unsigned int i;
2368	for (i = 0; cmd_descr[i].text; i++)
2369		if (cmd_descr[i].command == command)
2370			return cmd_descr[i].text;
2371#endif
2372
2373	return "unknown";
2374}
2375EXPORT_SYMBOL_GPL(ata_get_cmd_name);
2376
2377/**
2378 *	ata_eh_link_report - report error handling to user
2379 *	@link: ATA link EH is going on
2380 *
2381 *	Report EH to user.
2382 *
2383 *	LOCKING:
2384 *	None.
2385 */
2386static void ata_eh_link_report(struct ata_link *link)
2387{
2388	struct ata_port *ap = link->ap;
2389	struct ata_eh_context *ehc = &link->eh_context;
2390	struct ata_queued_cmd *qc;
2391	const char *frozen, *desc;
2392	char tries_buf[16] = "";
2393	int tag, nr_failed = 0;
2394
2395	if (ehc->i.flags & ATA_EHI_QUIET)
2396		return;
2397
2398	desc = NULL;
2399	if (ehc->i.desc[0] != '\0')
2400		desc = ehc->i.desc;
2401
2402	ata_qc_for_each_raw(ap, qc, tag) {
2403		if (!(qc->flags & ATA_QCFLAG_EH) ||
2404		    ata_dev_phys_link(qc->dev) != link ||
2405		    ((qc->flags & ATA_QCFLAG_QUIET) &&
2406		     qc->err_mask == AC_ERR_DEV))
2407			continue;
2408		if (qc->flags & ATA_QCFLAG_SENSE_VALID && !qc->err_mask)
2409			continue;
2410
2411		nr_failed++;
2412	}
2413
2414	if (!nr_failed && !ehc->i.err_mask)
2415		return;
2416
2417	frozen = "";
2418	if (ata_port_is_frozen(ap))
2419		frozen = " frozen";
2420
2421	if (ap->eh_tries < ATA_EH_MAX_TRIES)
2422		snprintf(tries_buf, sizeof(tries_buf), " t%d",
2423			 ap->eh_tries);
2424
2425	if (ehc->i.dev) {
2426		ata_dev_err(ehc->i.dev, "exception Emask 0x%x "
2427			    "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2428			    ehc->i.err_mask, link->sactive, ehc->i.serror,
2429			    ehc->i.action, frozen, tries_buf);
2430		if (desc)
2431			ata_dev_err(ehc->i.dev, "%s\n", desc);
2432	} else {
2433		ata_link_err(link, "exception Emask 0x%x "
2434			     "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2435			     ehc->i.err_mask, link->sactive, ehc->i.serror,
2436			     ehc->i.action, frozen, tries_buf);
2437		if (desc)
2438			ata_link_err(link, "%s\n", desc);
2439	}
2440
2441#ifdef CONFIG_ATA_VERBOSE_ERROR
2442	if (ehc->i.serror)
2443		ata_link_err(link,
2444		  "SError: { %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s}\n",
2445		  ehc->i.serror & SERR_DATA_RECOVERED ? "RecovData " : "",
2446		  ehc->i.serror & SERR_COMM_RECOVERED ? "RecovComm " : "",
2447		  ehc->i.serror & SERR_DATA ? "UnrecovData " : "",
2448		  ehc->i.serror & SERR_PERSISTENT ? "Persist " : "",
2449		  ehc->i.serror & SERR_PROTOCOL ? "Proto " : "",
2450		  ehc->i.serror & SERR_INTERNAL ? "HostInt " : "",
2451		  ehc->i.serror & SERR_PHYRDY_CHG ? "PHYRdyChg " : "",
2452		  ehc->i.serror & SERR_PHY_INT_ERR ? "PHYInt " : "",
2453		  ehc->i.serror & SERR_COMM_WAKE ? "CommWake " : "",
2454		  ehc->i.serror & SERR_10B_8B_ERR ? "10B8B " : "",
2455		  ehc->i.serror & SERR_DISPARITY ? "Dispar " : "",
2456		  ehc->i.serror & SERR_CRC ? "BadCRC " : "",
2457		  ehc->i.serror & SERR_HANDSHAKE ? "Handshk " : "",
2458		  ehc->i.serror & SERR_LINK_SEQ_ERR ? "LinkSeq " : "",
2459		  ehc->i.serror & SERR_TRANS_ST_ERROR ? "TrStaTrns " : "",
2460		  ehc->i.serror & SERR_UNRECOG_FIS ? "UnrecFIS " : "",
2461		  ehc->i.serror & SERR_DEV_XCHG ? "DevExch " : "");
2462#endif
2463
2464	ata_qc_for_each_raw(ap, qc, tag) {
2465		struct ata_taskfile *cmd = &qc->tf, *res = &qc->result_tf;
2466		char data_buf[20] = "";
2467		char cdb_buf[70] = "";
2468
2469		if (!(qc->flags & ATA_QCFLAG_EH) ||
2470		    ata_dev_phys_link(qc->dev) != link || !qc->err_mask)
2471			continue;
2472
2473		if (qc->dma_dir != DMA_NONE) {
2474			static const char *dma_str[] = {
2475				[DMA_BIDIRECTIONAL]	= "bidi",
2476				[DMA_TO_DEVICE]		= "out",
2477				[DMA_FROM_DEVICE]	= "in",
2478			};
2479			const char *prot_str = NULL;
2480
2481			switch (qc->tf.protocol) {
2482			case ATA_PROT_UNKNOWN:
2483				prot_str = "unknown";
2484				break;
2485			case ATA_PROT_NODATA:
2486				prot_str = "nodata";
2487				break;
2488			case ATA_PROT_PIO:
2489				prot_str = "pio";
2490				break;
2491			case ATA_PROT_DMA:
2492				prot_str = "dma";
2493				break;
2494			case ATA_PROT_NCQ:
2495				prot_str = "ncq dma";
2496				break;
2497			case ATA_PROT_NCQ_NODATA:
2498				prot_str = "ncq nodata";
2499				break;
2500			case ATAPI_PROT_NODATA:
2501				prot_str = "nodata";
2502				break;
2503			case ATAPI_PROT_PIO:
2504				prot_str = "pio";
2505				break;
2506			case ATAPI_PROT_DMA:
2507				prot_str = "dma";
2508				break;
2509			}
2510			snprintf(data_buf, sizeof(data_buf), " %s %u %s",
2511				 prot_str, qc->nbytes, dma_str[qc->dma_dir]);
2512		}
2513
2514		if (ata_is_atapi(qc->tf.protocol)) {
2515			const u8 *cdb = qc->cdb;
2516			size_t cdb_len = qc->dev->cdb_len;
2517
2518			if (qc->scsicmd) {
2519				cdb = qc->scsicmd->cmnd;
2520				cdb_len = qc->scsicmd->cmd_len;
2521			}
2522			__scsi_format_command(cdb_buf, sizeof(cdb_buf),
2523					      cdb, cdb_len);
2524		} else
2525			ata_dev_err(qc->dev, "failed command: %s\n",
2526				    ata_get_cmd_name(cmd->command));
 
 
 
2527
2528		ata_dev_err(qc->dev,
2529			"cmd %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2530			"tag %d%s\n         %s"
2531			"res %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2532			"Emask 0x%x (%s)%s\n",
2533			cmd->command, cmd->feature, cmd->nsect,
2534			cmd->lbal, cmd->lbam, cmd->lbah,
2535			cmd->hob_feature, cmd->hob_nsect,
2536			cmd->hob_lbal, cmd->hob_lbam, cmd->hob_lbah,
2537			cmd->device, qc->tag, data_buf, cdb_buf,
2538			res->status, res->error, res->nsect,
2539			res->lbal, res->lbam, res->lbah,
2540			res->hob_feature, res->hob_nsect,
2541			res->hob_lbal, res->hob_lbam, res->hob_lbah,
2542			res->device, qc->err_mask, ata_err_string(qc->err_mask),
2543			qc->err_mask & AC_ERR_NCQ ? " <F>" : "");
2544
2545#ifdef CONFIG_ATA_VERBOSE_ERROR
2546		if (res->status & (ATA_BUSY | ATA_DRDY | ATA_DF | ATA_DRQ |
2547				   ATA_SENSE | ATA_ERR)) {
2548			if (res->status & ATA_BUSY)
2549				ata_dev_err(qc->dev, "status: { Busy }\n");
2550			else
2551				ata_dev_err(qc->dev, "status: { %s%s%s%s%s}\n",
2552				  res->status & ATA_DRDY ? "DRDY " : "",
2553				  res->status & ATA_DF ? "DF " : "",
2554				  res->status & ATA_DRQ ? "DRQ " : "",
2555				  res->status & ATA_SENSE ? "SENSE " : "",
2556				  res->status & ATA_ERR ? "ERR " : "");
2557		}
2558
2559		if (cmd->command != ATA_CMD_PACKET &&
2560		    (res->error & (ATA_ICRC | ATA_UNC | ATA_AMNF | ATA_IDNF |
2561				   ATA_ABORTED)))
2562			ata_dev_err(qc->dev, "error: { %s%s%s%s%s}\n",
2563				    res->error & ATA_ICRC ? "ICRC " : "",
2564				    res->error & ATA_UNC ? "UNC " : "",
2565				    res->error & ATA_AMNF ? "AMNF " : "",
2566				    res->error & ATA_IDNF ? "IDNF " : "",
2567				    res->error & ATA_ABORTED ? "ABRT " : "");
2568#endif
2569	}
2570}
2571
2572/**
2573 *	ata_eh_report - report error handling to user
2574 *	@ap: ATA port to report EH about
2575 *
2576 *	Report EH to user.
2577 *
2578 *	LOCKING:
2579 *	None.
2580 */
2581void ata_eh_report(struct ata_port *ap)
2582{
2583	struct ata_link *link;
2584
2585	ata_for_each_link(link, ap, HOST_FIRST)
2586		ata_eh_link_report(link);
2587}
2588
2589static int ata_do_reset(struct ata_link *link, ata_reset_fn_t reset,
2590			unsigned int *classes, unsigned long deadline,
2591			bool clear_classes)
2592{
2593	struct ata_device *dev;
2594
2595	if (clear_classes)
2596		ata_for_each_dev(dev, link, ALL)
2597			classes[dev->devno] = ATA_DEV_UNKNOWN;
2598
2599	return reset(link, classes, deadline);
2600}
2601
2602static int ata_eh_followup_srst_needed(struct ata_link *link, int rc)
2603{
2604	if ((link->flags & ATA_LFLAG_NO_SRST) || ata_link_offline(link))
2605		return 0;
2606	if (rc == -EAGAIN)
2607		return 1;
2608	if (sata_pmp_supported(link->ap) && ata_is_host_link(link))
2609		return 1;
2610	return 0;
2611}
2612
2613int ata_eh_reset(struct ata_link *link, int classify,
2614		 ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
2615		 ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
2616{
2617	struct ata_port *ap = link->ap;
2618	struct ata_link *slave = ap->slave_link;
2619	struct ata_eh_context *ehc = &link->eh_context;
2620	struct ata_eh_context *sehc = slave ? &slave->eh_context : NULL;
2621	unsigned int *classes = ehc->classes;
2622	unsigned int lflags = link->flags;
2623	int verbose = !(ehc->i.flags & ATA_EHI_QUIET);
2624	int max_tries = 0, try = 0;
2625	struct ata_link *failed_link;
2626	struct ata_device *dev;
2627	unsigned long deadline, now;
2628	ata_reset_fn_t reset;
2629	unsigned long flags;
2630	u32 sstatus;
2631	int nr_unknown, rc;
2632
2633	/*
2634	 * Prepare to reset
2635	 */
2636	while (ata_eh_reset_timeouts[max_tries] != UINT_MAX)
2637		max_tries++;
2638	if (link->flags & ATA_LFLAG_RST_ONCE)
2639		max_tries = 1;
2640	if (link->flags & ATA_LFLAG_NO_HRST)
2641		hardreset = NULL;
2642	if (link->flags & ATA_LFLAG_NO_SRST)
2643		softreset = NULL;
2644
2645	/* make sure each reset attempt is at least COOL_DOWN apart */
2646	if (ehc->i.flags & ATA_EHI_DID_RESET) {
2647		now = jiffies;
2648		WARN_ON(time_after(ehc->last_reset, now));
2649		deadline = ata_deadline(ehc->last_reset,
2650					ATA_EH_RESET_COOL_DOWN);
2651		if (time_before(now, deadline))
2652			schedule_timeout_uninterruptible(deadline - now);
2653	}
2654
2655	spin_lock_irqsave(ap->lock, flags);
2656	ap->pflags |= ATA_PFLAG_RESETTING;
2657	spin_unlock_irqrestore(ap->lock, flags);
2658
2659	ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2660
2661	ata_for_each_dev(dev, link, ALL) {
2662		/* If we issue an SRST then an ATA drive (not ATAPI)
2663		 * may change configuration and be in PIO0 timing. If
2664		 * we do a hard reset (or are coming from power on)
2665		 * this is true for ATA or ATAPI. Until we've set a
2666		 * suitable controller mode we should not touch the
2667		 * bus as we may be talking too fast.
2668		 */
2669		dev->pio_mode = XFER_PIO_0;
2670		dev->dma_mode = 0xff;
2671
2672		/* If the controller has a pio mode setup function
2673		 * then use it to set the chipset to rights. Don't
2674		 * touch the DMA setup as that will be dealt with when
2675		 * configuring devices.
2676		 */
2677		if (ap->ops->set_piomode)
2678			ap->ops->set_piomode(ap, dev);
2679	}
2680
2681	/* prefer hardreset */
2682	reset = NULL;
2683	ehc->i.action &= ~ATA_EH_RESET;
2684	if (hardreset) {
2685		reset = hardreset;
2686		ehc->i.action |= ATA_EH_HARDRESET;
2687	} else if (softreset) {
2688		reset = softreset;
2689		ehc->i.action |= ATA_EH_SOFTRESET;
2690	}
2691
2692	if (prereset) {
2693		unsigned long deadline = ata_deadline(jiffies,
2694						      ATA_EH_PRERESET_TIMEOUT);
2695
2696		if (slave) {
2697			sehc->i.action &= ~ATA_EH_RESET;
2698			sehc->i.action |= ehc->i.action;
2699		}
2700
2701		rc = prereset(link, deadline);
2702
2703		/* If present, do prereset on slave link too.  Reset
2704		 * is skipped iff both master and slave links report
2705		 * -ENOENT or clear ATA_EH_RESET.
2706		 */
2707		if (slave && (rc == 0 || rc == -ENOENT)) {
2708			int tmp;
2709
2710			tmp = prereset(slave, deadline);
2711			if (tmp != -ENOENT)
2712				rc = tmp;
2713
2714			ehc->i.action |= sehc->i.action;
2715		}
2716
2717		if (rc) {
2718			if (rc == -ENOENT) {
2719				ata_link_dbg(link, "port disabled--ignoring\n");
2720				ehc->i.action &= ~ATA_EH_RESET;
2721
2722				ata_for_each_dev(dev, link, ALL)
2723					classes[dev->devno] = ATA_DEV_NONE;
2724
2725				rc = 0;
2726			} else
2727				ata_link_err(link,
2728					     "prereset failed (errno=%d)\n",
2729					     rc);
2730			goto out;
2731		}
2732
2733		/* prereset() might have cleared ATA_EH_RESET.  If so,
2734		 * bang classes, thaw and return.
2735		 */
2736		if (reset && !(ehc->i.action & ATA_EH_RESET)) {
2737			ata_for_each_dev(dev, link, ALL)
2738				classes[dev->devno] = ATA_DEV_NONE;
2739			if (ata_port_is_frozen(ap) && ata_is_host_link(link))
 
2740				ata_eh_thaw_port(ap);
2741			rc = 0;
2742			goto out;
2743		}
2744	}
2745
2746 retry:
2747	/*
2748	 * Perform reset
2749	 */
2750	if (ata_is_host_link(link))
2751		ata_eh_freeze_port(ap);
2752
2753	deadline = ata_deadline(jiffies, ata_eh_reset_timeouts[try++]);
2754
2755	if (reset) {
2756		if (verbose)
2757			ata_link_info(link, "%s resetting link\n",
2758				      reset == softreset ? "soft" : "hard");
2759
2760		/* mark that this EH session started with reset */
2761		ehc->last_reset = jiffies;
2762		if (reset == hardreset) {
2763			ehc->i.flags |= ATA_EHI_DID_HARDRESET;
2764			trace_ata_link_hardreset_begin(link, classes, deadline);
2765		} else {
2766			ehc->i.flags |= ATA_EHI_DID_SOFTRESET;
2767			trace_ata_link_softreset_begin(link, classes, deadline);
2768		}
2769
2770		rc = ata_do_reset(link, reset, classes, deadline, true);
2771		if (reset == hardreset)
2772			trace_ata_link_hardreset_end(link, classes, rc);
2773		else
2774			trace_ata_link_softreset_end(link, classes, rc);
2775		if (rc && rc != -EAGAIN) {
2776			failed_link = link;
2777			goto fail;
2778		}
2779
2780		/* hardreset slave link if existent */
2781		if (slave && reset == hardreset) {
2782			int tmp;
2783
2784			if (verbose)
2785				ata_link_info(slave, "hard resetting link\n");
2786
2787			ata_eh_about_to_do(slave, NULL, ATA_EH_RESET);
2788			trace_ata_slave_hardreset_begin(slave, classes,
2789							deadline);
2790			tmp = ata_do_reset(slave, reset, classes, deadline,
2791					   false);
2792			trace_ata_slave_hardreset_end(slave, classes, tmp);
2793			switch (tmp) {
2794			case -EAGAIN:
2795				rc = -EAGAIN;
2796				break;
2797			case 0:
2798				break;
2799			default:
2800				failed_link = slave;
2801				rc = tmp;
2802				goto fail;
2803			}
2804		}
2805
2806		/* perform follow-up SRST if necessary */
2807		if (reset == hardreset &&
2808		    ata_eh_followup_srst_needed(link, rc)) {
2809			reset = softreset;
2810
2811			if (!reset) {
2812				ata_link_err(link,
2813	     "follow-up softreset required but no softreset available\n");
2814				failed_link = link;
2815				rc = -EINVAL;
2816				goto fail;
2817			}
2818
2819			ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2820			trace_ata_link_softreset_begin(link, classes, deadline);
2821			rc = ata_do_reset(link, reset, classes, deadline, true);
2822			trace_ata_link_softreset_end(link, classes, rc);
2823			if (rc) {
2824				failed_link = link;
2825				goto fail;
2826			}
2827		}
2828	} else {
2829		if (verbose)
2830			ata_link_info(link,
2831	"no reset method available, skipping reset\n");
2832		if (!(lflags & ATA_LFLAG_ASSUME_CLASS))
2833			lflags |= ATA_LFLAG_ASSUME_ATA;
2834	}
2835
2836	/*
2837	 * Post-reset processing
2838	 */
2839	ata_for_each_dev(dev, link, ALL) {
2840		/* After the reset, the device state is PIO 0 and the
2841		 * controller state is undefined.  Reset also wakes up
2842		 * drives from sleeping mode.
2843		 */
2844		dev->pio_mode = XFER_PIO_0;
2845		dev->flags &= ~ATA_DFLAG_SLEEPING;
2846
2847		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
2848			continue;
2849
2850		/* apply class override */
2851		if (lflags & ATA_LFLAG_ASSUME_ATA)
2852			classes[dev->devno] = ATA_DEV_ATA;
2853		else if (lflags & ATA_LFLAG_ASSUME_SEMB)
2854			classes[dev->devno] = ATA_DEV_SEMB_UNSUP;
2855	}
2856
2857	/* record current link speed */
2858	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0)
2859		link->sata_spd = (sstatus >> 4) & 0xf;
2860	if (slave && sata_scr_read(slave, SCR_STATUS, &sstatus) == 0)
2861		slave->sata_spd = (sstatus >> 4) & 0xf;
2862
2863	/* thaw the port */
2864	if (ata_is_host_link(link))
2865		ata_eh_thaw_port(ap);
2866
2867	/* postreset() should clear hardware SError.  Although SError
2868	 * is cleared during link resume, clearing SError here is
2869	 * necessary as some PHYs raise hotplug events after SRST.
2870	 * This introduces race condition where hotplug occurs between
2871	 * reset and here.  This race is mediated by cross checking
2872	 * link onlineness and classification result later.
2873	 */
2874	if (postreset) {
2875		postreset(link, classes);
2876		trace_ata_link_postreset(link, classes, rc);
2877		if (slave) {
2878			postreset(slave, classes);
2879			trace_ata_slave_postreset(slave, classes, rc);
2880		}
2881	}
2882
2883	/* clear cached SError */
 
 
 
 
 
 
2884	spin_lock_irqsave(link->ap->lock, flags);
2885	link->eh_info.serror = 0;
2886	if (slave)
2887		slave->eh_info.serror = 0;
 
2888	spin_unlock_irqrestore(link->ap->lock, flags);
2889
 
 
 
2890	/*
2891	 * Make sure onlineness and classification result correspond.
2892	 * Hotplug could have happened during reset and some
2893	 * controllers fail to wait while a drive is spinning up after
2894	 * being hotplugged causing misdetection.  By cross checking
2895	 * link on/offlineness and classification result, those
2896	 * conditions can be reliably detected and retried.
2897	 */
2898	nr_unknown = 0;
2899	ata_for_each_dev(dev, link, ALL) {
2900		if (ata_phys_link_online(ata_dev_phys_link(dev))) {
2901			if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2902				ata_dev_dbg(dev, "link online but device misclassified\n");
2903				classes[dev->devno] = ATA_DEV_NONE;
2904				nr_unknown++;
2905			}
2906		} else if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
2907			if (ata_class_enabled(classes[dev->devno]))
2908				ata_dev_dbg(dev,
2909					    "link offline, clearing class %d to NONE\n",
2910					    classes[dev->devno]);
2911			classes[dev->devno] = ATA_DEV_NONE;
2912		} else if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2913			ata_dev_dbg(dev,
2914				    "link status unknown, clearing UNKNOWN to NONE\n");
2915			classes[dev->devno] = ATA_DEV_NONE;
2916		}
2917	}
2918
2919	if (classify && nr_unknown) {
2920		if (try < max_tries) {
2921			ata_link_warn(link,
2922				      "link online but %d devices misclassified, retrying\n",
2923				      nr_unknown);
2924			failed_link = link;
2925			rc = -EAGAIN;
2926			goto fail;
2927		}
2928		ata_link_warn(link,
2929			      "link online but %d devices misclassified, "
2930			      "device detection might fail\n", nr_unknown);
2931	}
2932
2933	/* reset successful, schedule revalidation */
2934	ata_eh_done(link, NULL, ATA_EH_RESET);
2935	if (slave)
2936		ata_eh_done(slave, NULL, ATA_EH_RESET);
2937	ehc->last_reset = jiffies;		/* update to completion time */
2938	ehc->i.action |= ATA_EH_REVALIDATE;
2939	link->lpm_policy = ATA_LPM_UNKNOWN;	/* reset LPM state */
2940
2941	rc = 0;
2942 out:
2943	/* clear hotplug flag */
2944	ehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2945	if (slave)
2946		sehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2947
2948	spin_lock_irqsave(ap->lock, flags);
2949	ap->pflags &= ~ATA_PFLAG_RESETTING;
2950	spin_unlock_irqrestore(ap->lock, flags);
2951
2952	return rc;
2953
2954 fail:
2955	/* if SCR isn't accessible on a fan-out port, PMP needs to be reset */
2956	if (!ata_is_host_link(link) &&
2957	    sata_scr_read(link, SCR_STATUS, &sstatus))
2958		rc = -ERESTART;
2959
2960	if (try >= max_tries) {
2961		/*
2962		 * Thaw host port even if reset failed, so that the port
2963		 * can be retried on the next phy event.  This risks
2964		 * repeated EH runs but seems to be a better tradeoff than
2965		 * shutting down a port after a botched hotplug attempt.
2966		 */
2967		if (ata_is_host_link(link))
2968			ata_eh_thaw_port(ap);
2969		ata_link_warn(link, "%s failed\n",
2970			      reset == hardreset ? "hardreset" : "softreset");
2971		goto out;
2972	}
2973
2974	now = jiffies;
2975	if (time_before(now, deadline)) {
2976		unsigned long delta = deadline - now;
2977
2978		ata_link_warn(failed_link,
2979			"reset failed (errno=%d), retrying in %u secs\n",
2980			rc, DIV_ROUND_UP(jiffies_to_msecs(delta), 1000));
2981
2982		ata_eh_release(ap);
2983		while (delta)
2984			delta = schedule_timeout_uninterruptible(delta);
2985		ata_eh_acquire(ap);
2986	}
2987
2988	/*
2989	 * While disks spinup behind PMP, some controllers fail sending SRST.
2990	 * They need to be reset - as well as the PMP - before retrying.
2991	 */
2992	if (rc == -ERESTART) {
2993		if (ata_is_host_link(link))
2994			ata_eh_thaw_port(ap);
2995		goto out;
2996	}
2997
2998	if (try == max_tries - 1) {
2999		sata_down_spd_limit(link, 0);
3000		if (slave)
3001			sata_down_spd_limit(slave, 0);
3002	} else if (rc == -EPIPE)
3003		sata_down_spd_limit(failed_link, 0);
3004
3005	if (hardreset)
3006		reset = hardreset;
3007	goto retry;
3008}
3009
3010static inline void ata_eh_pull_park_action(struct ata_port *ap)
3011{
3012	struct ata_link *link;
3013	struct ata_device *dev;
3014	unsigned long flags;
3015
3016	/*
3017	 * This function can be thought of as an extended version of
3018	 * ata_eh_about_to_do() specially crafted to accommodate the
3019	 * requirements of ATA_EH_PARK handling. Since the EH thread
3020	 * does not leave the do {} while () loop in ata_eh_recover as
3021	 * long as the timeout for a park request to *one* device on
3022	 * the port has not expired, and since we still want to pick
3023	 * up park requests to other devices on the same port or
3024	 * timeout updates for the same device, we have to pull
3025	 * ATA_EH_PARK actions from eh_info into eh_context.i
3026	 * ourselves at the beginning of each pass over the loop.
3027	 *
3028	 * Additionally, all write accesses to &ap->park_req_pending
3029	 * through reinit_completion() (see below) or complete_all()
3030	 * (see ata_scsi_park_store()) are protected by the host lock.
3031	 * As a result we have that park_req_pending.done is zero on
3032	 * exit from this function, i.e. when ATA_EH_PARK actions for
3033	 * *all* devices on port ap have been pulled into the
3034	 * respective eh_context structs. If, and only if,
3035	 * park_req_pending.done is non-zero by the time we reach
3036	 * wait_for_completion_timeout(), another ATA_EH_PARK action
3037	 * has been scheduled for at least one of the devices on port
3038	 * ap and we have to cycle over the do {} while () loop in
3039	 * ata_eh_recover() again.
3040	 */
3041
3042	spin_lock_irqsave(ap->lock, flags);
3043	reinit_completion(&ap->park_req_pending);
3044	ata_for_each_link(link, ap, EDGE) {
3045		ata_for_each_dev(dev, link, ALL) {
3046			struct ata_eh_info *ehi = &link->eh_info;
3047
3048			link->eh_context.i.dev_action[dev->devno] |=
3049				ehi->dev_action[dev->devno] & ATA_EH_PARK;
3050			ata_eh_clear_action(link, dev, ehi, ATA_EH_PARK);
3051		}
3052	}
3053	spin_unlock_irqrestore(ap->lock, flags);
3054}
3055
3056static void ata_eh_park_issue_cmd(struct ata_device *dev, int park)
3057{
3058	struct ata_eh_context *ehc = &dev->link->eh_context;
3059	struct ata_taskfile tf;
3060	unsigned int err_mask;
3061
3062	ata_tf_init(dev, &tf);
3063	if (park) {
3064		ehc->unloaded_mask |= 1 << dev->devno;
3065		tf.command = ATA_CMD_IDLEIMMEDIATE;
3066		tf.feature = 0x44;
3067		tf.lbal = 0x4c;
3068		tf.lbam = 0x4e;
3069		tf.lbah = 0x55;
3070	} else {
3071		ehc->unloaded_mask &= ~(1 << dev->devno);
3072		tf.command = ATA_CMD_CHK_POWER;
3073	}
3074
3075	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
3076	tf.protocol = ATA_PROT_NODATA;
3077	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
3078	if (park && (err_mask || tf.lbal != 0xc4)) {
3079		ata_dev_err(dev, "head unload failed!\n");
3080		ehc->unloaded_mask &= ~(1 << dev->devno);
3081	}
3082}
3083
3084static int ata_eh_revalidate_and_attach(struct ata_link *link,
3085					struct ata_device **r_failed_dev)
3086{
3087	struct ata_port *ap = link->ap;
3088	struct ata_eh_context *ehc = &link->eh_context;
3089	struct ata_device *dev;
3090	unsigned int new_mask = 0;
3091	unsigned long flags;
3092	int rc = 0;
3093
 
 
3094	/* For PATA drive side cable detection to work, IDENTIFY must
3095	 * be done backwards such that PDIAG- is released by the slave
3096	 * device before the master device is identified.
3097	 */
3098	ata_for_each_dev(dev, link, ALL_REVERSE) {
3099		unsigned int action = ata_eh_dev_action(dev);
3100		unsigned int readid_flags = 0;
3101
3102		if (ehc->i.flags & ATA_EHI_DID_RESET)
3103			readid_flags |= ATA_READID_POSTRESET;
3104
3105		if ((action & ATA_EH_REVALIDATE) && ata_dev_enabled(dev)) {
3106			WARN_ON(dev->class == ATA_DEV_PMP);
3107
3108			/*
3109			 * The link may be in a deep sleep, wake it up.
3110			 *
3111			 * If the link is in deep sleep, ata_phys_link_offline()
3112			 * will return true, causing the revalidation to fail,
3113			 * which leads to a (potentially) needless hard reset.
3114			 *
3115			 * ata_eh_recover() will later restore the link policy
3116			 * to ap->target_lpm_policy after revalidation is done.
3117			 */
3118			if (link->lpm_policy > ATA_LPM_MAX_POWER) {
3119				rc = ata_eh_set_lpm(link, ATA_LPM_MAX_POWER,
3120						    r_failed_dev);
3121				if (rc)
3122					goto err;
3123			}
3124
3125			if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
3126				rc = -EIO;
3127				goto err;
3128			}
3129
3130			ata_eh_about_to_do(link, dev, ATA_EH_REVALIDATE);
3131			rc = ata_dev_revalidate(dev, ehc->classes[dev->devno],
3132						readid_flags);
3133			if (rc)
3134				goto err;
3135
3136			ata_eh_done(link, dev, ATA_EH_REVALIDATE);
3137
3138			/* Configuration may have changed, reconfigure
3139			 * transfer mode.
3140			 */
3141			ehc->i.flags |= ATA_EHI_SETMODE;
3142
3143			/* schedule the scsi_rescan_device() here */
3144			schedule_delayed_work(&ap->scsi_rescan_task, 0);
3145		} else if (dev->class == ATA_DEV_UNKNOWN &&
3146			   ehc->tries[dev->devno] &&
3147			   ata_class_enabled(ehc->classes[dev->devno])) {
3148			/* Temporarily set dev->class, it will be
3149			 * permanently set once all configurations are
3150			 * complete.  This is necessary because new
3151			 * device configuration is done in two
3152			 * separate loops.
3153			 */
3154			dev->class = ehc->classes[dev->devno];
3155
3156			if (dev->class == ATA_DEV_PMP)
3157				rc = sata_pmp_attach(dev);
3158			else
3159				rc = ata_dev_read_id(dev, &dev->class,
3160						     readid_flags, dev->id);
3161
3162			/* read_id might have changed class, store and reset */
3163			ehc->classes[dev->devno] = dev->class;
3164			dev->class = ATA_DEV_UNKNOWN;
3165
3166			switch (rc) {
3167			case 0:
3168				/* clear error info accumulated during probe */
3169				ata_ering_clear(&dev->ering);
3170				new_mask |= 1 << dev->devno;
3171				break;
3172			case -ENOENT:
3173				/* IDENTIFY was issued to non-existent
3174				 * device.  No need to reset.  Just
3175				 * thaw and ignore the device.
3176				 */
3177				ata_eh_thaw_port(ap);
3178				break;
3179			default:
3180				goto err;
3181			}
3182		}
3183	}
3184
3185	/* PDIAG- should have been released, ask cable type if post-reset */
3186	if ((ehc->i.flags & ATA_EHI_DID_RESET) && ata_is_host_link(link)) {
3187		if (ap->ops->cable_detect)
3188			ap->cbl = ap->ops->cable_detect(ap);
3189		ata_force_cbl(ap);
3190	}
3191
3192	/* Configure new devices forward such that user doesn't see
3193	 * device detection messages backwards.
3194	 */
3195	ata_for_each_dev(dev, link, ALL) {
3196		if (!(new_mask & (1 << dev->devno)))
3197			continue;
3198
3199		dev->class = ehc->classes[dev->devno];
3200
3201		if (dev->class == ATA_DEV_PMP)
3202			continue;
3203
3204		ehc->i.flags |= ATA_EHI_PRINTINFO;
3205		rc = ata_dev_configure(dev);
3206		ehc->i.flags &= ~ATA_EHI_PRINTINFO;
3207		if (rc) {
3208			dev->class = ATA_DEV_UNKNOWN;
3209			goto err;
3210		}
3211
3212		spin_lock_irqsave(ap->lock, flags);
3213		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
3214		spin_unlock_irqrestore(ap->lock, flags);
3215
3216		/* new device discovered, configure xfermode */
3217		ehc->i.flags |= ATA_EHI_SETMODE;
3218	}
3219
3220	return 0;
3221
3222 err:
3223	dev->flags &= ~ATA_DFLAG_RESUMING;
3224	*r_failed_dev = dev;
 
3225	return rc;
3226}
3227
3228/**
3229 *	ata_set_mode - Program timings and issue SET FEATURES - XFER
3230 *	@link: link on which timings will be programmed
3231 *	@r_failed_dev: out parameter for failed device
3232 *
3233 *	Set ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3234 *	ata_set_mode() fails, pointer to the failing device is
3235 *	returned in @r_failed_dev.
3236 *
3237 *	LOCKING:
3238 *	PCI/etc. bus probe sem.
3239 *
3240 *	RETURNS:
3241 *	0 on success, negative errno otherwise
3242 */
3243int ata_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3244{
3245	struct ata_port *ap = link->ap;
3246	struct ata_device *dev;
3247	int rc;
3248
3249	/* if data transfer is verified, clear DUBIOUS_XFER on ering top */
3250	ata_for_each_dev(dev, link, ENABLED) {
3251		if (!(dev->flags & ATA_DFLAG_DUBIOUS_XFER)) {
3252			struct ata_ering_entry *ent;
3253
3254			ent = ata_ering_top(&dev->ering);
3255			if (ent)
3256				ent->eflags &= ~ATA_EFLAG_DUBIOUS_XFER;
3257		}
3258	}
3259
3260	/* has private set_mode? */
3261	if (ap->ops->set_mode)
3262		rc = ap->ops->set_mode(link, r_failed_dev);
3263	else
3264		rc = ata_do_set_mode(link, r_failed_dev);
3265
3266	/* if transfer mode has changed, set DUBIOUS_XFER on device */
3267	ata_for_each_dev(dev, link, ENABLED) {
3268		struct ata_eh_context *ehc = &link->eh_context;
3269		u8 saved_xfer_mode = ehc->saved_xfer_mode[dev->devno];
3270		u8 saved_ncq = !!(ehc->saved_ncq_enabled & (1 << dev->devno));
3271
3272		if (dev->xfer_mode != saved_xfer_mode ||
3273		    ata_ncq_enabled(dev) != saved_ncq)
3274			dev->flags |= ATA_DFLAG_DUBIOUS_XFER;
3275	}
3276
3277	return rc;
3278}
3279
3280/**
3281 *	atapi_eh_clear_ua - Clear ATAPI UNIT ATTENTION after reset
3282 *	@dev: ATAPI device to clear UA for
3283 *
3284 *	Resets and other operations can make an ATAPI device raise
3285 *	UNIT ATTENTION which causes the next operation to fail.  This
3286 *	function clears UA.
3287 *
3288 *	LOCKING:
3289 *	EH context (may sleep).
3290 *
3291 *	RETURNS:
3292 *	0 on success, -errno on failure.
3293 */
3294static int atapi_eh_clear_ua(struct ata_device *dev)
3295{
3296	int i;
3297
3298	for (i = 0; i < ATA_EH_UA_TRIES; i++) {
3299		u8 *sense_buffer = dev->sector_buf;
3300		u8 sense_key = 0;
3301		unsigned int err_mask;
3302
3303		err_mask = atapi_eh_tur(dev, &sense_key);
3304		if (err_mask != 0 && err_mask != AC_ERR_DEV) {
3305			ata_dev_warn(dev,
3306				     "TEST_UNIT_READY failed (err_mask=0x%x)\n",
3307				     err_mask);
3308			return -EIO;
3309		}
3310
3311		if (!err_mask || sense_key != UNIT_ATTENTION)
3312			return 0;
3313
3314		err_mask = atapi_eh_request_sense(dev, sense_buffer, sense_key);
3315		if (err_mask) {
3316			ata_dev_warn(dev, "failed to clear "
3317				"UNIT ATTENTION (err_mask=0x%x)\n", err_mask);
3318			return -EIO;
3319		}
3320	}
3321
3322	ata_dev_warn(dev, "UNIT ATTENTION persists after %d tries\n",
3323		     ATA_EH_UA_TRIES);
3324
3325	return 0;
3326}
3327
3328/**
3329 *	ata_eh_maybe_retry_flush - Retry FLUSH if necessary
3330 *	@dev: ATA device which may need FLUSH retry
3331 *
3332 *	If @dev failed FLUSH, it needs to be reported upper layer
3333 *	immediately as it means that @dev failed to remap and already
3334 *	lost at least a sector and further FLUSH retrials won't make
3335 *	any difference to the lost sector.  However, if FLUSH failed
3336 *	for other reasons, for example transmission error, FLUSH needs
3337 *	to be retried.
3338 *
3339 *	This function determines whether FLUSH failure retry is
3340 *	necessary and performs it if so.
3341 *
3342 *	RETURNS:
3343 *	0 if EH can continue, -errno if EH needs to be repeated.
3344 */
3345static int ata_eh_maybe_retry_flush(struct ata_device *dev)
3346{
3347	struct ata_link *link = dev->link;
3348	struct ata_port *ap = link->ap;
3349	struct ata_queued_cmd *qc;
3350	struct ata_taskfile tf;
3351	unsigned int err_mask;
3352	int rc = 0;
3353
3354	/* did flush fail for this device? */
3355	if (!ata_tag_valid(link->active_tag))
3356		return 0;
3357
3358	qc = __ata_qc_from_tag(ap, link->active_tag);
3359	if (qc->dev != dev || (qc->tf.command != ATA_CMD_FLUSH_EXT &&
3360			       qc->tf.command != ATA_CMD_FLUSH))
3361		return 0;
3362
3363	/* if the device failed it, it should be reported to upper layers */
3364	if (qc->err_mask & AC_ERR_DEV)
3365		return 0;
3366
3367	/* flush failed for some other reason, give it another shot */
3368	ata_tf_init(dev, &tf);
3369
3370	tf.command = qc->tf.command;
3371	tf.flags |= ATA_TFLAG_DEVICE;
3372	tf.protocol = ATA_PROT_NODATA;
3373
3374	ata_dev_warn(dev, "retrying FLUSH 0x%x Emask 0x%x\n",
3375		       tf.command, qc->err_mask);
3376
3377	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
3378	if (!err_mask) {
3379		/*
3380		 * FLUSH is complete but there's no way to
3381		 * successfully complete a failed command from EH.
3382		 * Making sure retry is allowed at least once and
3383		 * retrying it should do the trick - whatever was in
3384		 * the cache is already on the platter and this won't
3385		 * cause infinite loop.
3386		 */
3387		qc->scsicmd->allowed = max(qc->scsicmd->allowed, 1);
3388	} else {
3389		ata_dev_warn(dev, "FLUSH failed Emask 0x%x\n",
3390			       err_mask);
3391		rc = -EIO;
3392
3393		/* if device failed it, report it to upper layers */
3394		if (err_mask & AC_ERR_DEV) {
3395			qc->err_mask |= AC_ERR_DEV;
3396			qc->result_tf = tf;
3397			if (!ata_port_is_frozen(ap))
3398				rc = 0;
3399		}
3400	}
3401	return rc;
3402}
3403
3404/**
3405 *	ata_eh_set_lpm - configure SATA interface power management
3406 *	@link: link to configure power management
3407 *	@policy: the link power management policy
3408 *	@r_failed_dev: out parameter for failed device
3409 *
3410 *	Enable SATA Interface power management.  This will enable
3411 *	Device Interface Power Management (DIPM) for min_power and
3412 *	medium_power_with_dipm policies, and then call driver specific
3413 *	callbacks for enabling Host Initiated Power management.
3414 *
3415 *	LOCKING:
3416 *	EH context.
3417 *
3418 *	RETURNS:
3419 *	0 on success, -errno on failure.
3420 */
3421static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
3422			  struct ata_device **r_failed_dev)
3423{
3424	struct ata_port *ap = ata_is_host_link(link) ? link->ap : NULL;
3425	struct ata_eh_context *ehc = &link->eh_context;
3426	struct ata_device *dev, *link_dev = NULL, *lpm_dev = NULL;
3427	enum ata_lpm_policy old_policy = link->lpm_policy;
3428	bool no_dipm = link->ap->flags & ATA_FLAG_NO_DIPM;
3429	unsigned int hints = ATA_LPM_EMPTY | ATA_LPM_HIPM;
3430	unsigned int err_mask;
3431	int rc;
3432
3433	/* if the link or host doesn't do LPM, noop */
3434	if (!IS_ENABLED(CONFIG_SATA_HOST) ||
3435	    (link->flags & ATA_LFLAG_NO_LPM) || (ap && !ap->ops->set_lpm))
3436		return 0;
3437
3438	/*
3439	 * DIPM is enabled only for MIN_POWER as some devices
3440	 * misbehave when the host NACKs transition to SLUMBER.  Order
3441	 * device and link configurations such that the host always
3442	 * allows DIPM requests.
3443	 */
3444	ata_for_each_dev(dev, link, ENABLED) {
3445		bool hipm = ata_id_has_hipm(dev->id);
3446		bool dipm = ata_id_has_dipm(dev->id) && !no_dipm;
3447
3448		/* find the first enabled and LPM enabled devices */
3449		if (!link_dev)
3450			link_dev = dev;
3451
3452		if (!lpm_dev && (hipm || dipm))
3453			lpm_dev = dev;
3454
3455		hints &= ~ATA_LPM_EMPTY;
3456		if (!hipm)
3457			hints &= ~ATA_LPM_HIPM;
3458
3459		/* disable DIPM before changing link config */
3460		if (policy < ATA_LPM_MED_POWER_WITH_DIPM && dipm) {
3461			err_mask = ata_dev_set_feature(dev,
3462					SETFEATURES_SATA_DISABLE, SATA_DIPM);
3463			if (err_mask && err_mask != AC_ERR_DEV) {
3464				ata_dev_warn(dev,
3465					     "failed to disable DIPM, Emask 0x%x\n",
3466					     err_mask);
3467				rc = -EIO;
3468				goto fail;
3469			}
3470		}
3471	}
3472
3473	if (ap) {
3474		rc = ap->ops->set_lpm(link, policy, hints);
3475		if (!rc && ap->slave_link)
3476			rc = ap->ops->set_lpm(ap->slave_link, policy, hints);
3477	} else
3478		rc = sata_pmp_set_lpm(link, policy, hints);
3479
3480	/*
3481	 * Attribute link config failure to the first (LPM) enabled
3482	 * device on the link.
3483	 */
3484	if (rc) {
3485		if (rc == -EOPNOTSUPP) {
3486			link->flags |= ATA_LFLAG_NO_LPM;
3487			return 0;
3488		}
3489		dev = lpm_dev ? lpm_dev : link_dev;
3490		goto fail;
3491	}
3492
3493	/*
3494	 * Low level driver acked the transition.  Issue DIPM command
3495	 * with the new policy set.
3496	 */
3497	link->lpm_policy = policy;
3498	if (ap && ap->slave_link)
3499		ap->slave_link->lpm_policy = policy;
3500
3501	/* host config updated, enable DIPM if transitioning to MIN_POWER */
3502	ata_for_each_dev(dev, link, ENABLED) {
3503		if (policy >= ATA_LPM_MED_POWER_WITH_DIPM && !no_dipm &&
3504		    ata_id_has_dipm(dev->id)) {
3505			err_mask = ata_dev_set_feature(dev,
3506					SETFEATURES_SATA_ENABLE, SATA_DIPM);
3507			if (err_mask && err_mask != AC_ERR_DEV) {
3508				ata_dev_warn(dev,
3509					"failed to enable DIPM, Emask 0x%x\n",
3510					err_mask);
3511				rc = -EIO;
3512				goto fail;
3513			}
3514		}
3515	}
3516
3517	link->last_lpm_change = jiffies;
3518	link->flags |= ATA_LFLAG_CHANGED;
3519
3520	return 0;
3521
3522fail:
3523	/* restore the old policy */
3524	link->lpm_policy = old_policy;
3525	if (ap && ap->slave_link)
3526		ap->slave_link->lpm_policy = old_policy;
3527
3528	/* if no device or only one more chance is left, disable LPM */
3529	if (!dev || ehc->tries[dev->devno] <= 2) {
3530		ata_link_warn(link, "disabling LPM on the link\n");
3531		link->flags |= ATA_LFLAG_NO_LPM;
3532	}
3533	if (r_failed_dev)
3534		*r_failed_dev = dev;
3535	return rc;
3536}
3537
3538int ata_link_nr_enabled(struct ata_link *link)
3539{
3540	struct ata_device *dev;
3541	int cnt = 0;
3542
3543	ata_for_each_dev(dev, link, ENABLED)
3544		cnt++;
3545	return cnt;
3546}
3547
3548static int ata_link_nr_vacant(struct ata_link *link)
3549{
3550	struct ata_device *dev;
3551	int cnt = 0;
3552
3553	ata_for_each_dev(dev, link, ALL)
3554		if (dev->class == ATA_DEV_UNKNOWN)
3555			cnt++;
3556	return cnt;
3557}
3558
3559static int ata_eh_skip_recovery(struct ata_link *link)
3560{
3561	struct ata_port *ap = link->ap;
3562	struct ata_eh_context *ehc = &link->eh_context;
3563	struct ata_device *dev;
3564
3565	/* skip disabled links */
3566	if (link->flags & ATA_LFLAG_DISABLED)
3567		return 1;
3568
3569	/* skip if explicitly requested */
3570	if (ehc->i.flags & ATA_EHI_NO_RECOVERY)
3571		return 1;
3572
3573	/* thaw frozen port and recover failed devices */
3574	if (ata_port_is_frozen(ap) || ata_link_nr_enabled(link))
3575		return 0;
3576
3577	/* reset at least once if reset is requested */
3578	if ((ehc->i.action & ATA_EH_RESET) &&
3579	    !(ehc->i.flags & ATA_EHI_DID_RESET))
3580		return 0;
3581
3582	/* skip if class codes for all vacant slots are ATA_DEV_NONE */
3583	ata_for_each_dev(dev, link, ALL) {
3584		if (dev->class == ATA_DEV_UNKNOWN &&
3585		    ehc->classes[dev->devno] != ATA_DEV_NONE)
3586			return 0;
3587	}
3588
3589	return 1;
3590}
3591
3592static int ata_count_probe_trials_cb(struct ata_ering_entry *ent, void *void_arg)
3593{
3594	u64 interval = msecs_to_jiffies(ATA_EH_PROBE_TRIAL_INTERVAL);
3595	u64 now = get_jiffies_64();
3596	int *trials = void_arg;
3597
3598	if ((ent->eflags & ATA_EFLAG_OLD_ER) ||
3599	    (ent->timestamp < now - min(now, interval)))
3600		return -1;
3601
3602	(*trials)++;
3603	return 0;
3604}
3605
3606static int ata_eh_schedule_probe(struct ata_device *dev)
3607{
3608	struct ata_eh_context *ehc = &dev->link->eh_context;
3609	struct ata_link *link = ata_dev_phys_link(dev);
3610	int trials = 0;
3611
3612	if (!(ehc->i.probe_mask & (1 << dev->devno)) ||
3613	    (ehc->did_probe_mask & (1 << dev->devno)))
3614		return 0;
3615
3616	ata_eh_detach_dev(dev);
3617	ata_dev_init(dev);
3618	ehc->did_probe_mask |= (1 << dev->devno);
3619	ehc->i.action |= ATA_EH_RESET;
3620	ehc->saved_xfer_mode[dev->devno] = 0;
3621	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
3622
3623	/* the link maybe in a deep sleep, wake it up */
3624	if (link->lpm_policy > ATA_LPM_MAX_POWER) {
3625		if (ata_is_host_link(link))
3626			link->ap->ops->set_lpm(link, ATA_LPM_MAX_POWER,
3627					       ATA_LPM_EMPTY);
3628		else
3629			sata_pmp_set_lpm(link, ATA_LPM_MAX_POWER,
3630					 ATA_LPM_EMPTY);
3631	}
3632
3633	/* Record and count probe trials on the ering.  The specific
3634	 * error mask used is irrelevant.  Because a successful device
3635	 * detection clears the ering, this count accumulates only if
3636	 * there are consecutive failed probes.
3637	 *
3638	 * If the count is equal to or higher than ATA_EH_PROBE_TRIALS
3639	 * in the last ATA_EH_PROBE_TRIAL_INTERVAL, link speed is
3640	 * forced to 1.5Gbps.
3641	 *
3642	 * This is to work around cases where failed link speed
3643	 * negotiation results in device misdetection leading to
3644	 * infinite DEVXCHG or PHRDY CHG events.
3645	 */
3646	ata_ering_record(&dev->ering, 0, AC_ERR_OTHER);
3647	ata_ering_map(&dev->ering, ata_count_probe_trials_cb, &trials);
3648
3649	if (trials > ATA_EH_PROBE_TRIALS)
3650		sata_down_spd_limit(link, 1);
3651
3652	return 1;
3653}
3654
3655static int ata_eh_handle_dev_fail(struct ata_device *dev, int err)
3656{
3657	struct ata_eh_context *ehc = &dev->link->eh_context;
3658
3659	/* -EAGAIN from EH routine indicates retry without prejudice.
3660	 * The requester is responsible for ensuring forward progress.
3661	 */
3662	if (err != -EAGAIN)
3663		ehc->tries[dev->devno]--;
3664
3665	switch (err) {
3666	case -ENODEV:
3667		/* device missing or wrong IDENTIFY data, schedule probing */
3668		ehc->i.probe_mask |= (1 << dev->devno);
3669		fallthrough;
3670	case -EINVAL:
3671		/* give it just one more chance */
3672		ehc->tries[dev->devno] = min(ehc->tries[dev->devno], 1);
3673		fallthrough;
3674	case -EIO:
3675		if (ehc->tries[dev->devno] == 1) {
3676			/* This is the last chance, better to slow
3677			 * down than lose it.
3678			 */
3679			sata_down_spd_limit(ata_dev_phys_link(dev), 0);
3680			if (dev->pio_mode > XFER_PIO_0)
3681				ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
3682		}
3683	}
3684
3685	if (ata_dev_enabled(dev) && !ehc->tries[dev->devno]) {
3686		/* disable device if it has used up all its chances */
3687		ata_dev_disable(dev);
3688
3689		/* detach if offline */
3690		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
3691			ata_eh_detach_dev(dev);
3692
3693		/* schedule probe if necessary */
3694		if (ata_eh_schedule_probe(dev)) {
3695			ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3696			memset(ehc->cmd_timeout_idx[dev->devno], 0,
3697			       sizeof(ehc->cmd_timeout_idx[dev->devno]));
3698		}
3699
3700		return 1;
3701	} else {
3702		ehc->i.action |= ATA_EH_RESET;
3703		return 0;
3704	}
3705}
3706
3707/**
3708 *	ata_eh_recover - recover host port after error
3709 *	@ap: host port to recover
3710 *	@prereset: prereset method (can be NULL)
3711 *	@softreset: softreset method (can be NULL)
3712 *	@hardreset: hardreset method (can be NULL)
3713 *	@postreset: postreset method (can be NULL)
3714 *	@r_failed_link: out parameter for failed link
3715 *
3716 *	This is the alpha and omega, eum and yang, heart and soul of
3717 *	libata exception handling.  On entry, actions required to
3718 *	recover each link and hotplug requests are recorded in the
3719 *	link's eh_context.  This function executes all the operations
3720 *	with appropriate retrials and fallbacks to resurrect failed
3721 *	devices, detach goners and greet newcomers.
3722 *
3723 *	LOCKING:
3724 *	Kernel thread context (may sleep).
3725 *
3726 *	RETURNS:
3727 *	0 on success, -errno on failure.
3728 */
3729int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
3730		   ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3731		   ata_postreset_fn_t postreset,
3732		   struct ata_link **r_failed_link)
3733{
3734	struct ata_link *link;
3735	struct ata_device *dev;
3736	int rc, nr_fails;
3737	unsigned long flags, deadline;
3738
 
 
3739	/* prep for recovery */
3740	ata_for_each_link(link, ap, EDGE) {
3741		struct ata_eh_context *ehc = &link->eh_context;
3742
3743		/* re-enable link? */
3744		if (ehc->i.action & ATA_EH_ENABLE_LINK) {
3745			ata_eh_about_to_do(link, NULL, ATA_EH_ENABLE_LINK);
3746			spin_lock_irqsave(ap->lock, flags);
3747			link->flags &= ~ATA_LFLAG_DISABLED;
3748			spin_unlock_irqrestore(ap->lock, flags);
3749			ata_eh_done(link, NULL, ATA_EH_ENABLE_LINK);
3750		}
3751
3752		ata_for_each_dev(dev, link, ALL) {
3753			if (link->flags & ATA_LFLAG_NO_RETRY)
3754				ehc->tries[dev->devno] = 1;
3755			else
3756				ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3757
3758			/* collect port action mask recorded in dev actions */
3759			ehc->i.action |= ehc->i.dev_action[dev->devno] &
3760					 ~ATA_EH_PERDEV_MASK;
3761			ehc->i.dev_action[dev->devno] &= ATA_EH_PERDEV_MASK;
3762
3763			/* process hotplug request */
3764			if (dev->flags & ATA_DFLAG_DETACH)
3765				ata_eh_detach_dev(dev);
3766
3767			/* schedule probe if necessary */
3768			if (!ata_dev_enabled(dev))
3769				ata_eh_schedule_probe(dev);
3770		}
3771	}
3772
3773 retry:
3774	rc = 0;
3775
3776	/* if UNLOADING, finish immediately */
3777	if (ap->pflags & ATA_PFLAG_UNLOADING)
3778		goto out;
3779
3780	/* prep for EH */
3781	ata_for_each_link(link, ap, EDGE) {
3782		struct ata_eh_context *ehc = &link->eh_context;
3783
3784		/* skip EH if possible. */
3785		if (ata_eh_skip_recovery(link))
3786			ehc->i.action = 0;
3787
3788		ata_for_each_dev(dev, link, ALL)
3789			ehc->classes[dev->devno] = ATA_DEV_UNKNOWN;
3790	}
3791
3792	/* reset */
3793	ata_for_each_link(link, ap, EDGE) {
3794		struct ata_eh_context *ehc = &link->eh_context;
3795
3796		if (!(ehc->i.action & ATA_EH_RESET))
3797			continue;
3798
3799		rc = ata_eh_reset(link, ata_link_nr_vacant(link),
3800				  prereset, softreset, hardreset, postreset);
3801		if (rc) {
3802			ata_link_err(link, "reset failed, giving up\n");
3803			goto out;
3804		}
3805	}
3806
3807	do {
3808		unsigned long now;
3809
3810		/*
3811		 * clears ATA_EH_PARK in eh_info and resets
3812		 * ap->park_req_pending
3813		 */
3814		ata_eh_pull_park_action(ap);
3815
3816		deadline = jiffies;
3817		ata_for_each_link(link, ap, EDGE) {
3818			ata_for_each_dev(dev, link, ALL) {
3819				struct ata_eh_context *ehc = &link->eh_context;
3820				unsigned long tmp;
3821
3822				if (dev->class != ATA_DEV_ATA &&
3823				    dev->class != ATA_DEV_ZAC)
3824					continue;
3825				if (!(ehc->i.dev_action[dev->devno] &
3826				      ATA_EH_PARK))
3827					continue;
3828				tmp = dev->unpark_deadline;
3829				if (time_before(deadline, tmp))
3830					deadline = tmp;
3831				else if (time_before_eq(tmp, jiffies))
3832					continue;
3833				if (ehc->unloaded_mask & (1 << dev->devno))
3834					continue;
3835
3836				ata_eh_park_issue_cmd(dev, 1);
3837			}
3838		}
3839
3840		now = jiffies;
3841		if (time_before_eq(deadline, now))
3842			break;
3843
3844		ata_eh_release(ap);
3845		deadline = wait_for_completion_timeout(&ap->park_req_pending,
3846						       deadline - now);
3847		ata_eh_acquire(ap);
3848	} while (deadline);
3849	ata_for_each_link(link, ap, EDGE) {
3850		ata_for_each_dev(dev, link, ALL) {
3851			if (!(link->eh_context.unloaded_mask &
3852			      (1 << dev->devno)))
3853				continue;
3854
3855			ata_eh_park_issue_cmd(dev, 0);
3856			ata_eh_done(link, dev, ATA_EH_PARK);
3857		}
3858	}
3859
3860	/* the rest */
3861	nr_fails = 0;
3862	ata_for_each_link(link, ap, PMP_FIRST) {
3863		struct ata_eh_context *ehc = &link->eh_context;
3864
3865		if (sata_pmp_attached(ap) && ata_is_host_link(link))
3866			goto config_lpm;
3867
3868		/* revalidate existing devices and attach new ones */
3869		rc = ata_eh_revalidate_and_attach(link, &dev);
3870		if (rc)
3871			goto rest_fail;
3872
3873		/* if PMP got attached, return, pmp EH will take care of it */
3874		if (link->device->class == ATA_DEV_PMP) {
3875			ehc->i.action = 0;
3876			return 0;
3877		}
3878
3879		/* configure transfer mode if necessary */
3880		if (ehc->i.flags & ATA_EHI_SETMODE) {
3881			rc = ata_set_mode(link, &dev);
3882			if (rc)
3883				goto rest_fail;
3884			ehc->i.flags &= ~ATA_EHI_SETMODE;
3885		}
3886
3887		/* If reset has been issued, clear UA to avoid
3888		 * disrupting the current users of the device.
3889		 */
3890		if (ehc->i.flags & ATA_EHI_DID_RESET) {
3891			ata_for_each_dev(dev, link, ALL) {
3892				if (dev->class != ATA_DEV_ATAPI)
3893					continue;
3894				rc = atapi_eh_clear_ua(dev);
3895				if (rc)
3896					goto rest_fail;
3897				if (zpodd_dev_enabled(dev))
3898					zpodd_post_poweron(dev);
3899			}
3900		}
3901
3902		/*
3903		 * Make sure to transition devices to the active power mode
3904		 * if needed (e.g. if we were scheduled on system resume).
3905		 */
3906		ata_for_each_dev(dev, link, ENABLED) {
3907			if (ehc->i.dev_action[dev->devno] & ATA_EH_SET_ACTIVE) {
3908				ata_dev_power_set_active(dev);
3909				ata_eh_done(link, dev, ATA_EH_SET_ACTIVE);
3910			}
3911		}
3912
3913		/* retry flush if necessary */
3914		ata_for_each_dev(dev, link, ALL) {
3915			if (dev->class != ATA_DEV_ATA &&
3916			    dev->class != ATA_DEV_ZAC)
3917				continue;
3918			rc = ata_eh_maybe_retry_flush(dev);
3919			if (rc)
3920				goto rest_fail;
3921		}
3922
3923	config_lpm:
3924		/* configure link power saving */
3925		if (link->lpm_policy != ap->target_lpm_policy) {
3926			rc = ata_eh_set_lpm(link, ap->target_lpm_policy, &dev);
3927			if (rc)
3928				goto rest_fail;
3929		}
3930
3931		/* this link is okay now */
3932		ehc->i.flags = 0;
3933		continue;
3934
3935	rest_fail:
3936		nr_fails++;
3937		if (dev)
3938			ata_eh_handle_dev_fail(dev, rc);
3939
3940		if (ata_port_is_frozen(ap)) {
3941			/* PMP reset requires working host port.
3942			 * Can't retry if it's frozen.
3943			 */
3944			if (sata_pmp_attached(ap))
3945				goto out;
3946			break;
3947		}
3948	}
3949
3950	if (nr_fails)
3951		goto retry;
3952
3953 out:
3954	if (rc && r_failed_link)
3955		*r_failed_link = link;
3956
 
3957	return rc;
3958}
3959
3960/**
3961 *	ata_eh_finish - finish up EH
3962 *	@ap: host port to finish EH for
3963 *
3964 *	Recovery is complete.  Clean up EH states and retry or finish
3965 *	failed qcs.
3966 *
3967 *	LOCKING:
3968 *	None.
3969 */
3970void ata_eh_finish(struct ata_port *ap)
3971{
3972	struct ata_queued_cmd *qc;
3973	int tag;
3974
3975	/* retry or finish qcs */
3976	ata_qc_for_each_raw(ap, qc, tag) {
3977		if (!(qc->flags & ATA_QCFLAG_EH))
3978			continue;
3979
3980		if (qc->err_mask) {
3981			/* FIXME: Once EH migration is complete,
3982			 * generate sense data in this function,
3983			 * considering both err_mask and tf.
3984			 */
3985			if (qc->flags & ATA_QCFLAG_RETRY) {
3986				/*
3987				 * Since qc->err_mask is set, ata_eh_qc_retry()
3988				 * will not increment scmd->allowed, so upper
3989				 * layer will only retry the command if it has
3990				 * not already been retried too many times.
3991				 */
3992				ata_eh_qc_retry(qc);
3993			} else {
3994				ata_eh_qc_complete(qc);
3995			}
3996		} else {
3997			if (qc->flags & ATA_QCFLAG_SENSE_VALID ||
3998			    qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD) {
3999				ata_eh_qc_complete(qc);
4000			} else {
4001				/* feed zero TF to sense generation */
4002				memset(&qc->result_tf, 0, sizeof(qc->result_tf));
4003				/*
4004				 * Since qc->err_mask is not set,
4005				 * ata_eh_qc_retry() will increment
4006				 * scmd->allowed, so upper layer is guaranteed
4007				 * to retry the command.
4008				 */
4009				ata_eh_qc_retry(qc);
4010			}
4011		}
4012	}
4013
4014	/* make sure nr_active_links is zero after EH */
4015	WARN_ON(ap->nr_active_links);
4016	ap->nr_active_links = 0;
4017}
4018
4019/**
4020 *	ata_do_eh - do standard error handling
4021 *	@ap: host port to handle error for
4022 *
4023 *	@prereset: prereset method (can be NULL)
4024 *	@softreset: softreset method (can be NULL)
4025 *	@hardreset: hardreset method (can be NULL)
4026 *	@postreset: postreset method (can be NULL)
4027 *
4028 *	Perform standard error handling sequence.
4029 *
4030 *	LOCKING:
4031 *	Kernel thread context (may sleep).
4032 */
4033void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
4034	       ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
4035	       ata_postreset_fn_t postreset)
4036{
4037	struct ata_device *dev;
4038	int rc;
4039
4040	ata_eh_autopsy(ap);
4041	ata_eh_report(ap);
4042
4043	rc = ata_eh_recover(ap, prereset, softreset, hardreset, postreset,
4044			    NULL);
4045	if (rc) {
4046		ata_for_each_dev(dev, &ap->link, ALL)
4047			ata_dev_disable(dev);
4048	}
4049
4050	ata_eh_finish(ap);
4051}
4052
4053/**
4054 *	ata_std_error_handler - standard error handler
4055 *	@ap: host port to handle error for
4056 *
4057 *	Standard error handler
4058 *
4059 *	LOCKING:
4060 *	Kernel thread context (may sleep).
4061 */
4062void ata_std_error_handler(struct ata_port *ap)
4063{
4064	struct ata_port_operations *ops = ap->ops;
4065	ata_reset_fn_t hardreset = ops->hardreset;
4066
4067	/* ignore built-in hardreset if SCR access is not available */
4068	if (hardreset == sata_std_hardreset && !sata_scr_valid(&ap->link))
4069		hardreset = NULL;
4070
4071	ata_do_eh(ap, ops->prereset, ops->softreset, hardreset, ops->postreset);
4072}
4073EXPORT_SYMBOL_GPL(ata_std_error_handler);
4074
4075#ifdef CONFIG_PM
4076/**
4077 *	ata_eh_handle_port_suspend - perform port suspend operation
4078 *	@ap: port to suspend
4079 *
4080 *	Suspend @ap.
4081 *
4082 *	LOCKING:
4083 *	Kernel thread context (may sleep).
4084 */
4085static void ata_eh_handle_port_suspend(struct ata_port *ap)
4086{
4087	unsigned long flags;
4088	int rc = 0;
4089	struct ata_device *dev;
4090	struct ata_link *link;
4091
4092	/* are we suspending? */
4093	spin_lock_irqsave(ap->lock, flags);
4094	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
4095	    ap->pm_mesg.event & PM_EVENT_RESUME) {
4096		spin_unlock_irqrestore(ap->lock, flags);
4097		return;
4098	}
4099	spin_unlock_irqrestore(ap->lock, flags);
4100
4101	WARN_ON(ap->pflags & ATA_PFLAG_SUSPENDED);
4102
4103	/*
4104	 * We will reach this point for all of the PM events:
4105	 * PM_EVENT_SUSPEND (if runtime pm, PM_EVENT_AUTO will also be set)
4106	 * PM_EVENT_FREEZE, and PM_EVENT_HIBERNATE.
4107	 *
4108	 * We do not want to perform disk spin down for PM_EVENT_FREEZE.
4109	 * (Spin down will be performed by the subsequent PM_EVENT_HIBERNATE.)
4110	 */
4111	if (!(ap->pm_mesg.event & PM_EVENT_FREEZE)) {
4112		/* Set all devices attached to the port in standby mode */
4113		ata_for_each_link(link, ap, HOST_FIRST) {
4114			ata_for_each_dev(dev, link, ENABLED)
4115				ata_dev_power_set_standby(dev);
4116		}
4117	}
4118
4119	/*
4120	 * If we have a ZPODD attached, check its zero
4121	 * power ready status before the port is frozen.
4122	 * Only needed for runtime suspend.
4123	 */
4124	if (PMSG_IS_AUTO(ap->pm_mesg)) {
4125		ata_for_each_dev(dev, &ap->link, ENABLED) {
4126			if (zpodd_dev_enabled(dev))
4127				zpodd_on_suspend(dev);
4128		}
4129	}
4130
 
 
 
 
 
4131	/* suspend */
4132	ata_eh_freeze_port(ap);
4133
4134	if (ap->ops->port_suspend)
4135		rc = ap->ops->port_suspend(ap, ap->pm_mesg);
4136
4137	ata_acpi_set_state(ap, ap->pm_mesg);
4138
4139	/* update the flags */
4140	spin_lock_irqsave(ap->lock, flags);
4141
4142	ap->pflags &= ~ATA_PFLAG_PM_PENDING;
4143	if (rc == 0)
4144		ap->pflags |= ATA_PFLAG_SUSPENDED;
4145	else if (ata_port_is_frozen(ap))
4146		ata_port_schedule_eh(ap);
4147
4148	spin_unlock_irqrestore(ap->lock, flags);
4149
4150	return;
4151}
4152
4153/**
4154 *	ata_eh_handle_port_resume - perform port resume operation
4155 *	@ap: port to resume
4156 *
4157 *	Resume @ap.
4158 *
4159 *	LOCKING:
4160 *	Kernel thread context (may sleep).
4161 */
4162static void ata_eh_handle_port_resume(struct ata_port *ap)
4163{
4164	struct ata_link *link;
4165	struct ata_device *dev;
4166	unsigned long flags;
4167
4168	/* are we resuming? */
4169	spin_lock_irqsave(ap->lock, flags);
4170	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
4171	    !(ap->pm_mesg.event & PM_EVENT_RESUME)) {
4172		spin_unlock_irqrestore(ap->lock, flags);
4173		return;
4174	}
4175	spin_unlock_irqrestore(ap->lock, flags);
4176
4177	WARN_ON(!(ap->pflags & ATA_PFLAG_SUSPENDED));
4178
4179	/*
4180	 * Error timestamps are in jiffies which doesn't run while
4181	 * suspended and PHY events during resume isn't too uncommon.
4182	 * When the two are combined, it can lead to unnecessary speed
4183	 * downs if the machine is suspended and resumed repeatedly.
4184	 * Clear error history.
4185	 */
4186	ata_for_each_link(link, ap, HOST_FIRST)
4187		ata_for_each_dev(dev, link, ALL)
4188			ata_ering_clear(&dev->ering);
4189
4190	ata_acpi_set_state(ap, ap->pm_mesg);
4191
4192	if (ap->ops->port_resume)
4193		ap->ops->port_resume(ap);
4194
4195	/* tell ACPI that we're resuming */
4196	ata_acpi_on_resume(ap);
4197
4198	/* update the flags */
4199	spin_lock_irqsave(ap->lock, flags);
4200	ap->pflags &= ~(ATA_PFLAG_PM_PENDING | ATA_PFLAG_SUSPENDED);
4201	ap->pflags |= ATA_PFLAG_RESUMING;
4202	spin_unlock_irqrestore(ap->lock, flags);
4203}
4204#endif /* CONFIG_PM */