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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 */
v3.1
 
   1/*
   2 *  libata-eh.c - libata error handling
   3 *
   4 *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
   5 *    		    Please ALWAYS copy linux-ide@vger.kernel.org
   6 *		    on emails.
   7 *
   8 *  Copyright 2006 Tejun Heo <htejun@gmail.com>
   9 *
  10 *
  11 *  This program is free software; you can redistribute it and/or
  12 *  modify it under the terms of the GNU General Public License as
  13 *  published by the Free Software Foundation; either version 2, or
  14 *  (at your option) any later version.
  15 *
  16 *  This program is distributed in the hope that it will be useful,
  17 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  19 *  General Public License for more details.
  20 *
  21 *  You should have received a copy of the GNU General Public License
  22 *  along with this program; see the file COPYING.  If not, write to
  23 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
  24 *  USA.
  25 *
  26 *
  27 *  libata documentation is available via 'make {ps|pdf}docs',
  28 *  as Documentation/DocBook/libata.*
  29 *
  30 *  Hardware documentation available from http://www.t13.org/ and
  31 *  http://www.sata-io.org/
  32 *
  33 */
  34
  35#include <linux/kernel.h>
  36#include <linux/blkdev.h>
 
  37#include <linux/pci.h>
  38#include <scsi/scsi.h>
  39#include <scsi/scsi_host.h>
  40#include <scsi/scsi_eh.h>
  41#include <scsi/scsi_device.h>
  42#include <scsi/scsi_cmnd.h>
  43#include <scsi/scsi_dbg.h>
  44#include "../scsi/scsi_transport_api.h"
  45
  46#include <linux/libata.h>
  47
 
  48#include "libata.h"
  49
  50enum {
  51	/* speed down verdicts */
  52	ATA_EH_SPDN_NCQ_OFF		= (1 << 0),
  53	ATA_EH_SPDN_SPEED_DOWN		= (1 << 1),
  54	ATA_EH_SPDN_FALLBACK_TO_PIO	= (1 << 2),
  55	ATA_EH_SPDN_KEEP_ERRORS		= (1 << 3),
  56
  57	/* error flags */
  58	ATA_EFLAG_IS_IO			= (1 << 0),
  59	ATA_EFLAG_DUBIOUS_XFER		= (1 << 1),
  60	ATA_EFLAG_OLD_ER                = (1 << 31),
  61
  62	/* error categories */
  63	ATA_ECAT_NONE			= 0,
  64	ATA_ECAT_ATA_BUS		= 1,
  65	ATA_ECAT_TOUT_HSM		= 2,
  66	ATA_ECAT_UNK_DEV		= 3,
  67	ATA_ECAT_DUBIOUS_NONE		= 4,
  68	ATA_ECAT_DUBIOUS_ATA_BUS	= 5,
  69	ATA_ECAT_DUBIOUS_TOUT_HSM	= 6,
  70	ATA_ECAT_DUBIOUS_UNK_DEV	= 7,
  71	ATA_ECAT_NR			= 8,
  72
  73	ATA_EH_CMD_DFL_TIMEOUT		=  5000,
  74
  75	/* always put at least this amount of time between resets */
  76	ATA_EH_RESET_COOL_DOWN		=  5000,
  77
  78	/* Waiting in ->prereset can never be reliable.  It's
  79	 * sometimes nice to wait there but it can't be depended upon;
  80	 * otherwise, we wouldn't be resetting.  Just give it enough
  81	 * time for most drives to spin up.
  82	 */
  83	ATA_EH_PRERESET_TIMEOUT		= 10000,
  84	ATA_EH_FASTDRAIN_INTERVAL	=  3000,
  85
  86	ATA_EH_UA_TRIES			= 5,
  87
  88	/* probe speed down parameters, see ata_eh_schedule_probe() */
  89	ATA_EH_PROBE_TRIAL_INTERVAL	= 60000,	/* 1 min */
  90	ATA_EH_PROBE_TRIALS		= 2,
  91};
  92
  93/* The following table determines how we sequence resets.  Each entry
  94 * represents timeout for that try.  The first try can be soft or
  95 * hardreset.  All others are hardreset if available.  In most cases
  96 * the first reset w/ 10sec timeout should succeed.  Following entries
  97 * are mostly for error handling, hotplug and retarded devices.
 
  98 */
  99static const unsigned long ata_eh_reset_timeouts[] = {
 100	10000,	/* most drives spin up by 10sec */
 101	10000,	/* > 99% working drives spin up before 20sec */
 102	35000,	/* give > 30 secs of idleness for retarded devices */
 103	 5000,	/* and sweet one last chance */
 104	ULONG_MAX, /* > 1 min has elapsed, give up */
 105};
 106
 107static const unsigned long ata_eh_identify_timeouts[] = {
 108	 5000,	/* covers > 99% of successes and not too boring on failures */
 109	10000,  /* combined time till here is enough even for media access */
 110	30000,	/* for true idiots */
 111	ULONG_MAX,
 112};
 113
 114static const unsigned long ata_eh_flush_timeouts[] = {
 115	15000,	/* be generous with flush */
 116	15000,  /* ditto */
 117	30000,	/* and even more generous */
 118	ULONG_MAX,
 119};
 120
 121static const unsigned long ata_eh_other_timeouts[] = {
 122	 5000,	/* same rationale as identify timeout */
 123	10000,	/* ditto */
 124	/* but no merciful 30sec for other commands, it just isn't worth it */
 125	ULONG_MAX,
 126};
 127
 128struct ata_eh_cmd_timeout_ent {
 129	const u8		*commands;
 130	const unsigned long	*timeouts;
 131};
 132
 133/* The following table determines timeouts to use for EH internal
 134 * commands.  Each table entry is a command class and matches the
 135 * commands the entry applies to and the timeout table to use.
 136 *
 137 * On the retry after a command timed out, the next timeout value from
 138 * the table is used.  If the table doesn't contain further entries,
 139 * the last value is used.
 140 *
 141 * ehc->cmd_timeout_idx keeps track of which timeout to use per
 142 * command class, so if SET_FEATURES times out on the first try, the
 143 * next try will use the second timeout value only for that class.
 144 */
 145#define CMDS(cmds...)	(const u8 []){ cmds, 0 }
 146static const struct ata_eh_cmd_timeout_ent
 147ata_eh_cmd_timeout_table[ATA_EH_CMD_TIMEOUT_TABLE_SIZE] = {
 148	{ .commands = CMDS(ATA_CMD_ID_ATA, ATA_CMD_ID_ATAPI),
 149	  .timeouts = ata_eh_identify_timeouts, },
 150	{ .commands = CMDS(ATA_CMD_READ_NATIVE_MAX, ATA_CMD_READ_NATIVE_MAX_EXT),
 151	  .timeouts = ata_eh_other_timeouts, },
 152	{ .commands = CMDS(ATA_CMD_SET_MAX, ATA_CMD_SET_MAX_EXT),
 153	  .timeouts = ata_eh_other_timeouts, },
 154	{ .commands = CMDS(ATA_CMD_SET_FEATURES),
 155	  .timeouts = ata_eh_other_timeouts, },
 156	{ .commands = CMDS(ATA_CMD_INIT_DEV_PARAMS),
 157	  .timeouts = ata_eh_other_timeouts, },
 158	{ .commands = CMDS(ATA_CMD_FLUSH, ATA_CMD_FLUSH_EXT),
 159	  .timeouts = ata_eh_flush_timeouts },
 160};
 161#undef CMDS
 162
 163static void __ata_port_freeze(struct ata_port *ap);
 164#ifdef CONFIG_PM
 165static void ata_eh_handle_port_suspend(struct ata_port *ap);
 166static void ata_eh_handle_port_resume(struct ata_port *ap);
 167#else /* CONFIG_PM */
 168static void ata_eh_handle_port_suspend(struct ata_port *ap)
 169{ }
 170
 171static void ata_eh_handle_port_resume(struct ata_port *ap)
 172{ }
 173#endif /* CONFIG_PM */
 174
 175static void __ata_ehi_pushv_desc(struct ata_eh_info *ehi, const char *fmt,
 176				 va_list args)
 177{
 178	ehi->desc_len += vscnprintf(ehi->desc + ehi->desc_len,
 179				     ATA_EH_DESC_LEN - ehi->desc_len,
 180				     fmt, args);
 181}
 182
 183/**
 184 *	__ata_ehi_push_desc - push error description without adding separator
 185 *	@ehi: target EHI
 186 *	@fmt: printf format string
 187 *
 188 *	Format string according to @fmt and append it to @ehi->desc.
 189 *
 190 *	LOCKING:
 191 *	spin_lock_irqsave(host lock)
 192 */
 193void __ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 194{
 195	va_list args;
 196
 197	va_start(args, fmt);
 198	__ata_ehi_pushv_desc(ehi, fmt, args);
 199	va_end(args);
 200}
 
 201
 202/**
 203 *	ata_ehi_push_desc - push error description with separator
 204 *	@ehi: target EHI
 205 *	@fmt: printf format string
 206 *
 207 *	Format string according to @fmt and append it to @ehi->desc.
 208 *	If @ehi->desc is not empty, ", " is added in-between.
 209 *
 210 *	LOCKING:
 211 *	spin_lock_irqsave(host lock)
 212 */
 213void ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 214{
 215	va_list args;
 216
 217	if (ehi->desc_len)
 218		__ata_ehi_push_desc(ehi, ", ");
 219
 220	va_start(args, fmt);
 221	__ata_ehi_pushv_desc(ehi, fmt, args);
 222	va_end(args);
 223}
 
 224
 225/**
 226 *	ata_ehi_clear_desc - clean error description
 227 *	@ehi: target EHI
 228 *
 229 *	Clear @ehi->desc.
 230 *
 231 *	LOCKING:
 232 *	spin_lock_irqsave(host lock)
 233 */
 234void ata_ehi_clear_desc(struct ata_eh_info *ehi)
 235{
 236	ehi->desc[0] = '\0';
 237	ehi->desc_len = 0;
 238}
 
 239
 240/**
 241 *	ata_port_desc - append port description
 242 *	@ap: target ATA port
 243 *	@fmt: printf format string
 244 *
 245 *	Format string according to @fmt and append it to port
 246 *	description.  If port description is not empty, " " is added
 247 *	in-between.  This function is to be used while initializing
 248 *	ata_host.  The description is printed on host registration.
 249 *
 250 *	LOCKING:
 251 *	None.
 252 */
 253void ata_port_desc(struct ata_port *ap, const char *fmt, ...)
 254{
 255	va_list args;
 256
 257	WARN_ON(!(ap->pflags & ATA_PFLAG_INITIALIZING));
 258
 259	if (ap->link.eh_info.desc_len)
 260		__ata_ehi_push_desc(&ap->link.eh_info, " ");
 261
 262	va_start(args, fmt);
 263	__ata_ehi_pushv_desc(&ap->link.eh_info, fmt, args);
 264	va_end(args);
 265}
 
 266
 267#ifdef CONFIG_PCI
 268
 269/**
 270 *	ata_port_pbar_desc - append PCI BAR description
 271 *	@ap: target ATA port
 272 *	@bar: target PCI BAR
 273 *	@offset: offset into PCI BAR
 274 *	@name: name of the area
 275 *
 276 *	If @offset is negative, this function formats a string which
 277 *	contains the name, address, size and type of the BAR and
 278 *	appends it to the port description.  If @offset is zero or
 279 *	positive, only name and offsetted address is appended.
 280 *
 281 *	LOCKING:
 282 *	None.
 283 */
 284void ata_port_pbar_desc(struct ata_port *ap, int bar, ssize_t offset,
 285			const char *name)
 286{
 287	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 288	char *type = "";
 289	unsigned long long start, len;
 290
 291	if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
 292		type = "m";
 293	else if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
 294		type = "i";
 295
 296	start = (unsigned long long)pci_resource_start(pdev, bar);
 297	len = (unsigned long long)pci_resource_len(pdev, bar);
 298
 299	if (offset < 0)
 300		ata_port_desc(ap, "%s %s%llu@0x%llx", name, type, len, start);
 301	else
 302		ata_port_desc(ap, "%s 0x%llx", name,
 303				start + (unsigned long long)offset);
 304}
 305
 306#endif /* CONFIG_PCI */
 307
 308static int ata_lookup_timeout_table(u8 cmd)
 309{
 310	int i;
 311
 312	for (i = 0; i < ATA_EH_CMD_TIMEOUT_TABLE_SIZE; i++) {
 313		const u8 *cur;
 314
 315		for (cur = ata_eh_cmd_timeout_table[i].commands; *cur; cur++)
 316			if (*cur == cmd)
 317				return i;
 318	}
 319
 320	return -1;
 321}
 322
 323/**
 324 *	ata_internal_cmd_timeout - determine timeout for an internal command
 325 *	@dev: target device
 326 *	@cmd: internal command to be issued
 327 *
 328 *	Determine timeout for internal command @cmd for @dev.
 329 *
 330 *	LOCKING:
 331 *	EH context.
 332 *
 333 *	RETURNS:
 334 *	Determined timeout.
 335 */
 336unsigned long ata_internal_cmd_timeout(struct ata_device *dev, u8 cmd)
 337{
 338	struct ata_eh_context *ehc = &dev->link->eh_context;
 339	int ent = ata_lookup_timeout_table(cmd);
 340	int idx;
 341
 342	if (ent < 0)
 343		return ATA_EH_CMD_DFL_TIMEOUT;
 344
 345	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 346	return ata_eh_cmd_timeout_table[ent].timeouts[idx];
 347}
 348
 349/**
 350 *	ata_internal_cmd_timed_out - notification for internal command timeout
 351 *	@dev: target device
 352 *	@cmd: internal command which timed out
 353 *
 354 *	Notify EH that internal command @cmd for @dev timed out.  This
 355 *	function should be called only for commands whose timeouts are
 356 *	determined using ata_internal_cmd_timeout().
 357 *
 358 *	LOCKING:
 359 *	EH context.
 360 */
 361void ata_internal_cmd_timed_out(struct ata_device *dev, u8 cmd)
 362{
 363	struct ata_eh_context *ehc = &dev->link->eh_context;
 364	int ent = ata_lookup_timeout_table(cmd);
 365	int idx;
 366
 367	if (ent < 0)
 368		return;
 369
 370	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 371	if (ata_eh_cmd_timeout_table[ent].timeouts[idx + 1] != ULONG_MAX)
 372		ehc->cmd_timeout_idx[dev->devno][ent]++;
 373}
 374
 375static void ata_ering_record(struct ata_ering *ering, unsigned int eflags,
 376			     unsigned int err_mask)
 377{
 378	struct ata_ering_entry *ent;
 379
 380	WARN_ON(!err_mask);
 381
 382	ering->cursor++;
 383	ering->cursor %= ATA_ERING_SIZE;
 384
 385	ent = &ering->ring[ering->cursor];
 386	ent->eflags = eflags;
 387	ent->err_mask = err_mask;
 388	ent->timestamp = get_jiffies_64();
 389}
 390
 391static struct ata_ering_entry *ata_ering_top(struct ata_ering *ering)
 392{
 393	struct ata_ering_entry *ent = &ering->ring[ering->cursor];
 394
 395	if (ent->err_mask)
 396		return ent;
 397	return NULL;
 398}
 399
 400int ata_ering_map(struct ata_ering *ering,
 401		  int (*map_fn)(struct ata_ering_entry *, void *),
 402		  void *arg)
 403{
 404	int idx, rc = 0;
 405	struct ata_ering_entry *ent;
 406
 407	idx = ering->cursor;
 408	do {
 409		ent = &ering->ring[idx];
 410		if (!ent->err_mask)
 411			break;
 412		rc = map_fn(ent, arg);
 413		if (rc)
 414			break;
 415		idx = (idx - 1 + ATA_ERING_SIZE) % ATA_ERING_SIZE;
 416	} while (idx != ering->cursor);
 417
 418	return rc;
 419}
 420
 421int ata_ering_clear_cb(struct ata_ering_entry *ent, void *void_arg)
 422{
 423	ent->eflags |= ATA_EFLAG_OLD_ER;
 424	return 0;
 425}
 426
 427static void ata_ering_clear(struct ata_ering *ering)
 428{
 429	ata_ering_map(ering, ata_ering_clear_cb, NULL);
 430}
 431
 432static unsigned int ata_eh_dev_action(struct ata_device *dev)
 433{
 434	struct ata_eh_context *ehc = &dev->link->eh_context;
 435
 436	return ehc->i.action | ehc->i.dev_action[dev->devno];
 437}
 438
 439static void ata_eh_clear_action(struct ata_link *link, struct ata_device *dev,
 440				struct ata_eh_info *ehi, unsigned int action)
 441{
 442	struct ata_device *tdev;
 443
 444	if (!dev) {
 445		ehi->action &= ~action;
 446		ata_for_each_dev(tdev, link, ALL)
 447			ehi->dev_action[tdev->devno] &= ~action;
 448	} else {
 449		/* doesn't make sense for port-wide EH actions */
 450		WARN_ON(!(action & ATA_EH_PERDEV_MASK));
 451
 452		/* break ehi->action into ehi->dev_action */
 453		if (ehi->action & action) {
 454			ata_for_each_dev(tdev, link, ALL)
 455				ehi->dev_action[tdev->devno] |=
 456					ehi->action & action;
 457			ehi->action &= ~action;
 458		}
 459
 460		/* turn off the specified per-dev action */
 461		ehi->dev_action[dev->devno] &= ~action;
 462	}
 463}
 464
 465/**
 466 *	ata_eh_acquire - acquire EH ownership
 467 *	@ap: ATA port to acquire EH ownership for
 468 *
 469 *	Acquire EH ownership for @ap.  This is the basic exclusion
 470 *	mechanism for ports sharing a host.  Only one port hanging off
 471 *	the same host can claim the ownership of EH.
 472 *
 473 *	LOCKING:
 474 *	EH context.
 475 */
 476void ata_eh_acquire(struct ata_port *ap)
 477{
 478	mutex_lock(&ap->host->eh_mutex);
 479	WARN_ON_ONCE(ap->host->eh_owner);
 480	ap->host->eh_owner = current;
 481}
 482
 483/**
 484 *	ata_eh_release - release EH ownership
 485 *	@ap: ATA port to release EH ownership for
 486 *
 487 *	Release EH ownership for @ap if the caller.  The caller must
 488 *	have acquired EH ownership using ata_eh_acquire() previously.
 489 *
 490 *	LOCKING:
 491 *	EH context.
 492 */
 493void ata_eh_release(struct ata_port *ap)
 494{
 495	WARN_ON_ONCE(ap->host->eh_owner != current);
 496	ap->host->eh_owner = NULL;
 497	mutex_unlock(&ap->host->eh_mutex);
 498}
 499
 500/**
 501 *	ata_scsi_timed_out - SCSI layer time out callback
 502 *	@cmd: timed out SCSI command
 503 *
 504 *	Handles SCSI layer timeout.  We race with normal completion of
 505 *	the qc for @cmd.  If the qc is already gone, we lose and let
 506 *	the scsi command finish (EH_HANDLED).  Otherwise, the qc has
 507 *	timed out and EH should be invoked.  Prevent ata_qc_complete()
 508 *	from finishing it by setting EH_SCHEDULED and return
 509 *	EH_NOT_HANDLED.
 510 *
 511 *	TODO: kill this function once old EH is gone.
 512 *
 513 *	LOCKING:
 514 *	Called from timer context
 515 *
 516 *	RETURNS:
 517 *	EH_HANDLED or EH_NOT_HANDLED
 518 */
 519enum blk_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd)
 520{
 521	struct Scsi_Host *host = cmd->device->host;
 522	struct ata_port *ap = ata_shost_to_port(host);
 523	unsigned long flags;
 524	struct ata_queued_cmd *qc;
 525	enum blk_eh_timer_return ret;
 526
 527	DPRINTK("ENTER\n");
 528
 529	if (ap->ops->error_handler) {
 530		ret = BLK_EH_NOT_HANDLED;
 531		goto out;
 532	}
 533
 534	ret = BLK_EH_HANDLED;
 535	spin_lock_irqsave(ap->lock, flags);
 536	qc = ata_qc_from_tag(ap, ap->link.active_tag);
 537	if (qc) {
 538		WARN_ON(qc->scsicmd != cmd);
 539		qc->flags |= ATA_QCFLAG_EH_SCHEDULED;
 540		qc->err_mask |= AC_ERR_TIMEOUT;
 541		ret = BLK_EH_NOT_HANDLED;
 542	}
 543	spin_unlock_irqrestore(ap->lock, flags);
 544
 545 out:
 546	DPRINTK("EXIT, ret=%d\n", ret);
 547	return ret;
 548}
 549
 550static void ata_eh_unload(struct ata_port *ap)
 551{
 552	struct ata_link *link;
 553	struct ata_device *dev;
 554	unsigned long flags;
 555
 556	/* Restore SControl IPM and SPD for the next driver and
 557	 * disable attached devices.
 558	 */
 559	ata_for_each_link(link, ap, PMP_FIRST) {
 560		sata_scr_write(link, SCR_CONTROL, link->saved_scontrol & 0xff0);
 561		ata_for_each_dev(dev, link, ALL)
 562			ata_dev_disable(dev);
 563	}
 564
 565	/* freeze and set UNLOADED */
 566	spin_lock_irqsave(ap->lock, flags);
 567
 568	ata_port_freeze(ap);			/* won't be thawed */
 569	ap->pflags &= ~ATA_PFLAG_EH_PENDING;	/* clear pending from freeze */
 570	ap->pflags |= ATA_PFLAG_UNLOADED;
 571
 572	spin_unlock_irqrestore(ap->lock, flags);
 573}
 574
 575/**
 576 *	ata_scsi_error - SCSI layer error handler callback
 577 *	@host: SCSI host on which error occurred
 578 *
 579 *	Handles SCSI-layer-thrown error events.
 580 *
 581 *	LOCKING:
 582 *	Inherited from SCSI layer (none, can sleep)
 583 *
 584 *	RETURNS:
 585 *	Zero.
 586 */
 587void ata_scsi_error(struct Scsi_Host *host)
 588{
 589	struct ata_port *ap = ata_shost_to_port(host);
 590	unsigned long flags;
 591	LIST_HEAD(eh_work_q);
 592
 593	DPRINTK("ENTER\n");
 594
 595	spin_lock_irqsave(host->host_lock, flags);
 596	list_splice_init(&host->eh_cmd_q, &eh_work_q);
 597	spin_unlock_irqrestore(host->host_lock, flags);
 598
 599	ata_scsi_cmd_error_handler(host, ap, &eh_work_q);
 600
 601	/* If we timed raced normal completion and there is nothing to
 602	   recover nr_timedout == 0 why exactly are we doing error recovery ? */
 603	ata_scsi_port_error_handler(host, ap);
 604
 605	/* finish or retry handled scmd's and clean up */
 606	WARN_ON(host->host_failed || !list_empty(&eh_work_q));
 607
 608	DPRINTK("EXIT\n");
 609}
 610
 611/**
 612 * ata_scsi_cmd_error_handler - error callback for a list of commands
 613 * @host:	scsi host containing the port
 614 * @ap:		ATA port within the host
 615 * @eh_work_q:	list of commands to process
 616 *
 617 * process the given list of commands and return those finished to the
 618 * ap->eh_done_q.  This function is the first part of the libata error
 619 * handler which processes a given list of failed commands.
 620 */
 621void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
 622				struct list_head *eh_work_q)
 623{
 624	int i;
 625	unsigned long flags;
 626
 627	/* make sure sff pio task is not running */
 628	ata_sff_flush_pio_task(ap);
 629
 630	/* synchronize with host lock and sort out timeouts */
 631
 632	/* For new EH, all qcs are finished in one of three ways -
 633	 * normal completion, error completion, and SCSI timeout.
 634	 * Both completions can race against SCSI timeout.  When normal
 635	 * completion wins, the qc never reaches EH.  When error
 636	 * completion wins, the qc has ATA_QCFLAG_FAILED set.
 637	 *
 638	 * When SCSI timeout wins, things are a bit more complex.
 639	 * Normal or error completion can occur after the timeout but
 640	 * before this point.  In such cases, both types of
 641	 * completions are honored.  A scmd is determined to have
 642	 * timed out iff its associated qc is active and not failed.
 643	 */
 
 644	if (ap->ops->error_handler) {
 645		struct scsi_cmnd *scmd, *tmp;
 646		int nr_timedout = 0;
 647
 648		spin_lock_irqsave(ap->lock, flags);
 649
 650		/* This must occur under the ap->lock as we don't want
 651		   a polled recovery to race the real interrupt handler
 652
 653		   The lost_interrupt handler checks for any completed but
 654		   non-notified command and completes much like an IRQ handler.
 655
 656		   We then fall into the error recovery code which will treat
 657		   this as if normal completion won the race */
 658
 659		if (ap->ops->lost_interrupt)
 660			ap->ops->lost_interrupt(ap);
 661
 662		list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
 663			struct ata_queued_cmd *qc;
 664
 665			for (i = 0; i < ATA_MAX_QUEUE; i++) {
 666				qc = __ata_qc_from_tag(ap, i);
 667				if (qc->flags & ATA_QCFLAG_ACTIVE &&
 668				    qc->scsicmd == scmd)
 669					break;
 670			}
 671
 672			if (i < ATA_MAX_QUEUE) {
 673				/* the scmd has an associated qc */
 674				if (!(qc->flags & ATA_QCFLAG_FAILED)) {
 675					/* which hasn't failed yet, timeout */
 676					qc->err_mask |= AC_ERR_TIMEOUT;
 677					qc->flags |= ATA_QCFLAG_FAILED;
 678					nr_timedout++;
 679				}
 680			} else {
 681				/* Normal completion occurred after
 682				 * SCSI timeout but before this point.
 683				 * Successfully complete it.
 684				 */
 685				scmd->retries = scmd->allowed;
 686				scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
 687			}
 688		}
 689
 690		/* If we have timed out qcs.  They belong to EH from
 691		 * this point but the state of the controller is
 692		 * unknown.  Freeze the port to make sure the IRQ
 693		 * handler doesn't diddle with those qcs.  This must
 694		 * be done atomically w.r.t. setting QCFLAG_FAILED.
 695		 */
 696		if (nr_timedout)
 697			__ata_port_freeze(ap);
 698
 699		spin_unlock_irqrestore(ap->lock, flags);
 700
 701		/* initialize eh_tries */
 702		ap->eh_tries = ATA_EH_MAX_TRIES;
 703	} else
 704		spin_unlock_wait(ap->lock);
 705
 706}
 707EXPORT_SYMBOL(ata_scsi_cmd_error_handler);
 708
 709/**
 710 * ata_scsi_port_error_handler - recover the port after the commands
 711 * @host:	SCSI host containing the port
 712 * @ap:		the ATA port
 713 *
 714 * Handle the recovery of the port @ap after all the commands
 715 * have been recovered.
 716 */
 717void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap)
 718{
 719	unsigned long flags;
 720
 721	/* invoke error handler */
 722	if (ap->ops->error_handler) {
 723		struct ata_link *link;
 724
 725		/* acquire EH ownership */
 726		ata_eh_acquire(ap);
 727 repeat:
 728		/* kill fast drain timer */
 729		del_timer_sync(&ap->fastdrain_timer);
 730
 731		/* process port resume request */
 732		ata_eh_handle_port_resume(ap);
 733
 734		/* fetch & clear EH info */
 735		spin_lock_irqsave(ap->lock, flags);
 736
 737		ata_for_each_link(link, ap, HOST_FIRST) {
 738			struct ata_eh_context *ehc = &link->eh_context;
 739			struct ata_device *dev;
 740
 741			memset(&link->eh_context, 0, sizeof(link->eh_context));
 742			link->eh_context.i = link->eh_info;
 743			memset(&link->eh_info, 0, sizeof(link->eh_info));
 744
 745			ata_for_each_dev(dev, link, ENABLED) {
 746				int devno = dev->devno;
 747
 748				ehc->saved_xfer_mode[devno] = dev->xfer_mode;
 749				if (ata_ncq_enabled(dev))
 750					ehc->saved_ncq_enabled |= 1 << devno;
 751			}
 752		}
 753
 754		ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
 755		ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 756		ap->excl_link = NULL;	/* don't maintain exclusion over EH */
 757
 758		spin_unlock_irqrestore(ap->lock, flags);
 759
 760		/* invoke EH, skip if unloading or suspended */
 761		if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))
 762			ap->ops->error_handler(ap);
 763		else {
 764			/* if unloading, commence suicide */
 765			if ((ap->pflags & ATA_PFLAG_UNLOADING) &&
 766			    !(ap->pflags & ATA_PFLAG_UNLOADED))
 767				ata_eh_unload(ap);
 768			ata_eh_finish(ap);
 769		}
 770
 771		/* process port suspend request */
 772		ata_eh_handle_port_suspend(ap);
 773
 774		/* Exception might have happened after ->error_handler
 775		 * recovered the port but before this point.  Repeat
 776		 * EH in such case.
 777		 */
 778		spin_lock_irqsave(ap->lock, flags);
 779
 780		if (ap->pflags & ATA_PFLAG_EH_PENDING) {
 781			if (--ap->eh_tries) {
 782				spin_unlock_irqrestore(ap->lock, flags);
 783				goto repeat;
 784			}
 785			ata_port_err(ap,
 786				     "EH pending after %d tries, giving up\n",
 787				     ATA_EH_MAX_TRIES);
 788			ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 789		}
 790
 791		/* this run is complete, make sure EH info is clear */
 792		ata_for_each_link(link, ap, HOST_FIRST)
 793			memset(&link->eh_info, 0, sizeof(link->eh_info));
 794
 795		/* Clear host_eh_scheduled while holding ap->lock such
 796		 * that if exception occurs after this point but
 797		 * before EH completion, SCSI midlayer will
 798		 * re-initiate EH.
 799		 */
 800		host->host_eh_scheduled = 0;
 801
 802		spin_unlock_irqrestore(ap->lock, flags);
 803		ata_eh_release(ap);
 804	} else {
 805		WARN_ON(ata_qc_from_tag(ap, ap->link.active_tag) == NULL);
 806		ap->ops->eng_timeout(ap);
 807	}
 808
 809	scsi_eh_flush_done_q(&ap->eh_done_q);
 810
 811	/* clean up */
 812	spin_lock_irqsave(ap->lock, flags);
 813
 814	if (ap->pflags & ATA_PFLAG_LOADING)
 815		ap->pflags &= ~ATA_PFLAG_LOADING;
 816	else if (ap->pflags & ATA_PFLAG_SCSI_HOTPLUG)
 
 817		schedule_delayed_work(&ap->hotplug_task, 0);
 818
 819	if (ap->pflags & ATA_PFLAG_RECOVERED)
 820		ata_port_info(ap, "EH complete\n");
 821
 822	ap->pflags &= ~(ATA_PFLAG_SCSI_HOTPLUG | ATA_PFLAG_RECOVERED);
 823
 824	/* tell wait_eh that we're done */
 825	ap->pflags &= ~ATA_PFLAG_EH_IN_PROGRESS;
 826	wake_up_all(&ap->eh_wait_q);
 827
 828	spin_unlock_irqrestore(ap->lock, flags);
 829}
 830EXPORT_SYMBOL_GPL(ata_scsi_port_error_handler);
 831
 832/**
 833 *	ata_port_wait_eh - Wait for the currently pending EH to complete
 834 *	@ap: Port to wait EH for
 835 *
 836 *	Wait until the currently pending EH is complete.
 837 *
 838 *	LOCKING:
 839 *	Kernel thread context (may sleep).
 840 */
 841void ata_port_wait_eh(struct ata_port *ap)
 842{
 843	unsigned long flags;
 844	DEFINE_WAIT(wait);
 845
 846 retry:
 847	spin_lock_irqsave(ap->lock, flags);
 848
 849	while (ap->pflags & (ATA_PFLAG_EH_PENDING | ATA_PFLAG_EH_IN_PROGRESS)) {
 850		prepare_to_wait(&ap->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 851		spin_unlock_irqrestore(ap->lock, flags);
 852		schedule();
 853		spin_lock_irqsave(ap->lock, flags);
 854	}
 855	finish_wait(&ap->eh_wait_q, &wait);
 856
 857	spin_unlock_irqrestore(ap->lock, flags);
 858
 859	/* make sure SCSI EH is complete */
 860	if (scsi_host_in_recovery(ap->scsi_host)) {
 861		ata_msleep(ap, 10);
 862		goto retry;
 863	}
 864}
 
 865
 866static int ata_eh_nr_in_flight(struct ata_port *ap)
 867{
 
 868	unsigned int tag;
 869	int nr = 0;
 870
 871	/* count only non-internal commands */
 872	for (tag = 0; tag < ATA_MAX_QUEUE - 1; tag++)
 873		if (ata_qc_from_tag(ap, tag))
 874			nr++;
 
 875
 876	return nr;
 877}
 878
 879void ata_eh_fastdrain_timerfn(unsigned long arg)
 880{
 881	struct ata_port *ap = (void *)arg;
 882	unsigned long flags;
 883	int cnt;
 884
 885	spin_lock_irqsave(ap->lock, flags);
 886
 887	cnt = ata_eh_nr_in_flight(ap);
 888
 889	/* are we done? */
 890	if (!cnt)
 891		goto out_unlock;
 892
 893	if (cnt == ap->fastdrain_cnt) {
 
 894		unsigned int tag;
 895
 896		/* No progress during the last interval, tag all
 897		 * in-flight qcs as timed out and freeze the port.
 898		 */
 899		for (tag = 0; tag < ATA_MAX_QUEUE - 1; tag++) {
 900			struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag);
 901			if (qc)
 902				qc->err_mask |= AC_ERR_TIMEOUT;
 903		}
 904
 905		ata_port_freeze(ap);
 906	} else {
 907		/* some qcs have finished, give it another chance */
 908		ap->fastdrain_cnt = cnt;
 909		ap->fastdrain_timer.expires =
 910			ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 911		add_timer(&ap->fastdrain_timer);
 912	}
 913
 914 out_unlock:
 915	spin_unlock_irqrestore(ap->lock, flags);
 916}
 917
 918/**
 919 *	ata_eh_set_pending - set ATA_PFLAG_EH_PENDING and activate fast drain
 920 *	@ap: target ATA port
 921 *	@fastdrain: activate fast drain
 922 *
 923 *	Set ATA_PFLAG_EH_PENDING and activate fast drain if @fastdrain
 924 *	is non-zero and EH wasn't pending before.  Fast drain ensures
 925 *	that EH kicks in in timely manner.
 926 *
 927 *	LOCKING:
 928 *	spin_lock_irqsave(host lock)
 929 */
 930static void ata_eh_set_pending(struct ata_port *ap, int fastdrain)
 931{
 932	int cnt;
 933
 934	/* already scheduled? */
 935	if (ap->pflags & ATA_PFLAG_EH_PENDING)
 936		return;
 937
 938	ap->pflags |= ATA_PFLAG_EH_PENDING;
 939
 940	if (!fastdrain)
 941		return;
 942
 943	/* do we have in-flight qcs? */
 944	cnt = ata_eh_nr_in_flight(ap);
 945	if (!cnt)
 946		return;
 947
 948	/* activate fast drain */
 949	ap->fastdrain_cnt = cnt;
 950	ap->fastdrain_timer.expires =
 951		ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 952	add_timer(&ap->fastdrain_timer);
 953}
 954
 955/**
 956 *	ata_qc_schedule_eh - schedule qc for error handling
 957 *	@qc: command to schedule error handling for
 958 *
 959 *	Schedule error handling for @qc.  EH will kick in as soon as
 960 *	other commands are drained.
 961 *
 962 *	LOCKING:
 963 *	spin_lock_irqsave(host lock)
 964 */
 965void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
 966{
 967	struct ata_port *ap = qc->ap;
 968	struct request_queue *q = qc->scsicmd->device->request_queue;
 969	unsigned long flags;
 970
 971	WARN_ON(!ap->ops->error_handler);
 972
 973	qc->flags |= ATA_QCFLAG_FAILED;
 974	ata_eh_set_pending(ap, 1);
 975
 976	/* The following will fail if timeout has already expired.
 977	 * ata_scsi_error() takes care of such scmds on EH entry.
 978	 * Note that ATA_QCFLAG_FAILED is unconditionally set after
 979	 * this function completes.
 980	 */
 981	spin_lock_irqsave(q->queue_lock, flags);
 982	blk_abort_request(qc->scsicmd->request);
 983	spin_unlock_irqrestore(q->queue_lock, flags);
 984}
 985
 986/**
 987 *	ata_port_schedule_eh - schedule error handling without a qc
 988 *	@ap: ATA port to schedule EH for
 989 *
 990 *	Schedule error handling for @ap.  EH will kick in as soon as
 991 *	all commands are drained.
 992 *
 993 *	LOCKING:
 994 *	spin_lock_irqsave(host lock)
 995 */
 996void ata_port_schedule_eh(struct ata_port *ap)
 997{
 998	WARN_ON(!ap->ops->error_handler);
 999
1000	if (ap->pflags & ATA_PFLAG_INITIALIZING)
1001		return;
1002
1003	ata_eh_set_pending(ap, 1);
1004	scsi_schedule_eh(ap->scsi_host);
1005
1006	DPRINTK("port EH scheduled\n");
1007}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1008
1009static int ata_do_link_abort(struct ata_port *ap, struct ata_link *link)
1010{
 
1011	int tag, nr_aborted = 0;
1012
1013	WARN_ON(!ap->ops->error_handler);
1014
1015	/* we're gonna abort all commands, no need for fast drain */
1016	ata_eh_set_pending(ap, 0);
1017
1018	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
1019		struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag);
1020
1021		if (qc && (!link || qc->dev->link == link)) {
1022			qc->flags |= ATA_QCFLAG_FAILED;
1023			ata_qc_complete(qc);
1024			nr_aborted++;
1025		}
1026	}
1027
1028	if (!nr_aborted)
1029		ata_port_schedule_eh(ap);
1030
1031	return nr_aborted;
1032}
1033
1034/**
1035 *	ata_link_abort - abort all qc's on the link
1036 *	@link: ATA link to abort qc's for
1037 *
1038 *	Abort all active qc's active on @link and schedule EH.
1039 *
1040 *	LOCKING:
1041 *	spin_lock_irqsave(host lock)
1042 *
1043 *	RETURNS:
1044 *	Number of aborted qc's.
1045 */
1046int ata_link_abort(struct ata_link *link)
1047{
1048	return ata_do_link_abort(link->ap, link);
1049}
 
1050
1051/**
1052 *	ata_port_abort - abort all qc's on the port
1053 *	@ap: ATA port to abort qc's for
1054 *
1055 *	Abort all active qc's of @ap and schedule EH.
1056 *
1057 *	LOCKING:
1058 *	spin_lock_irqsave(host_set lock)
1059 *
1060 *	RETURNS:
1061 *	Number of aborted qc's.
1062 */
1063int ata_port_abort(struct ata_port *ap)
1064{
1065	return ata_do_link_abort(ap, NULL);
1066}
 
1067
1068/**
1069 *	__ata_port_freeze - freeze port
1070 *	@ap: ATA port to freeze
1071 *
1072 *	This function is called when HSM violation or some other
1073 *	condition disrupts normal operation of the port.  Frozen port
1074 *	is not allowed to perform any operation until the port is
1075 *	thawed, which usually follows a successful reset.
1076 *
1077 *	ap->ops->freeze() callback can be used for freezing the port
1078 *	hardware-wise (e.g. mask interrupt and stop DMA engine).  If a
1079 *	port cannot be frozen hardware-wise, the interrupt handler
1080 *	must ack and clear interrupts unconditionally while the port
1081 *	is frozen.
1082 *
1083 *	LOCKING:
1084 *	spin_lock_irqsave(host lock)
1085 */
1086static void __ata_port_freeze(struct ata_port *ap)
1087{
1088	WARN_ON(!ap->ops->error_handler);
1089
1090	if (ap->ops->freeze)
1091		ap->ops->freeze(ap);
1092
1093	ap->pflags |= ATA_PFLAG_FROZEN;
1094
1095	DPRINTK("ata%u port frozen\n", ap->print_id);
1096}
1097
1098/**
1099 *	ata_port_freeze - abort & freeze port
1100 *	@ap: ATA port to freeze
1101 *
1102 *	Abort and freeze @ap.  The freeze operation must be called
1103 *	first, because some hardware requires special operations
1104 *	before the taskfile registers are accessible.
1105 *
1106 *	LOCKING:
1107 *	spin_lock_irqsave(host lock)
1108 *
1109 *	RETURNS:
1110 *	Number of aborted commands.
1111 */
1112int ata_port_freeze(struct ata_port *ap)
1113{
1114	int nr_aborted;
1115
1116	WARN_ON(!ap->ops->error_handler);
1117
1118	__ata_port_freeze(ap);
1119	nr_aborted = ata_port_abort(ap);
1120
1121	return nr_aborted;
1122}
1123
1124/**
1125 *	sata_async_notification - SATA async notification handler
1126 *	@ap: ATA port where async notification is received
1127 *
1128 *	Handler to be called when async notification via SDB FIS is
1129 *	received.  This function schedules EH if necessary.
1130 *
1131 *	LOCKING:
1132 *	spin_lock_irqsave(host lock)
1133 *
1134 *	RETURNS:
1135 *	1 if EH is scheduled, 0 otherwise.
1136 */
1137int sata_async_notification(struct ata_port *ap)
1138{
1139	u32 sntf;
1140	int rc;
1141
1142	if (!(ap->flags & ATA_FLAG_AN))
1143		return 0;
1144
1145	rc = sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf);
1146	if (rc == 0)
1147		sata_scr_write(&ap->link, SCR_NOTIFICATION, sntf);
1148
1149	if (!sata_pmp_attached(ap) || rc) {
1150		/* PMP is not attached or SNTF is not available */
1151		if (!sata_pmp_attached(ap)) {
1152			/* PMP is not attached.  Check whether ATAPI
1153			 * AN is configured.  If so, notify media
1154			 * change.
1155			 */
1156			struct ata_device *dev = ap->link.device;
1157
1158			if ((dev->class == ATA_DEV_ATAPI) &&
1159			    (dev->flags & ATA_DFLAG_AN))
1160				ata_scsi_media_change_notify(dev);
1161			return 0;
1162		} else {
1163			/* PMP is attached but SNTF is not available.
1164			 * ATAPI async media change notification is
1165			 * not used.  The PMP must be reporting PHY
1166			 * status change, schedule EH.
1167			 */
1168			ata_port_schedule_eh(ap);
1169			return 1;
1170		}
1171	} else {
1172		/* PMP is attached and SNTF is available */
1173		struct ata_link *link;
1174
1175		/* check and notify ATAPI AN */
1176		ata_for_each_link(link, ap, EDGE) {
1177			if (!(sntf & (1 << link->pmp)))
1178				continue;
1179
1180			if ((link->device->class == ATA_DEV_ATAPI) &&
1181			    (link->device->flags & ATA_DFLAG_AN))
1182				ata_scsi_media_change_notify(link->device);
1183		}
1184
1185		/* If PMP is reporting that PHY status of some
1186		 * downstream ports has changed, schedule EH.
1187		 */
1188		if (sntf & (1 << SATA_PMP_CTRL_PORT)) {
1189			ata_port_schedule_eh(ap);
1190			return 1;
1191		}
1192
1193		return 0;
1194	}
1195}
1196
1197/**
1198 *	ata_eh_freeze_port - EH helper to freeze port
1199 *	@ap: ATA port to freeze
1200 *
1201 *	Freeze @ap.
1202 *
1203 *	LOCKING:
1204 *	None.
1205 */
1206void ata_eh_freeze_port(struct ata_port *ap)
1207{
1208	unsigned long flags;
1209
1210	if (!ap->ops->error_handler)
1211		return;
1212
1213	spin_lock_irqsave(ap->lock, flags);
1214	__ata_port_freeze(ap);
1215	spin_unlock_irqrestore(ap->lock, flags);
1216}
 
1217
1218/**
1219 *	ata_port_thaw_port - EH helper to thaw port
1220 *	@ap: ATA port to thaw
1221 *
1222 *	Thaw frozen port @ap.
1223 *
1224 *	LOCKING:
1225 *	None.
1226 */
1227void ata_eh_thaw_port(struct ata_port *ap)
1228{
1229	unsigned long flags;
1230
1231	if (!ap->ops->error_handler)
1232		return;
1233
1234	spin_lock_irqsave(ap->lock, flags);
1235
1236	ap->pflags &= ~ATA_PFLAG_FROZEN;
1237
1238	if (ap->ops->thaw)
1239		ap->ops->thaw(ap);
1240
1241	spin_unlock_irqrestore(ap->lock, flags);
1242
1243	DPRINTK("ata%u port thawed\n", ap->print_id);
1244}
1245
1246static void ata_eh_scsidone(struct scsi_cmnd *scmd)
1247{
1248	/* nada */
1249}
1250
1251static void __ata_eh_qc_complete(struct ata_queued_cmd *qc)
1252{
1253	struct ata_port *ap = qc->ap;
1254	struct scsi_cmnd *scmd = qc->scsicmd;
1255	unsigned long flags;
1256
1257	spin_lock_irqsave(ap->lock, flags);
1258	qc->scsidone = ata_eh_scsidone;
1259	__ata_qc_complete(qc);
1260	WARN_ON(ata_tag_valid(qc->tag));
1261	spin_unlock_irqrestore(ap->lock, flags);
1262
1263	scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
1264}
1265
1266/**
1267 *	ata_eh_qc_complete - Complete an active ATA command from EH
1268 *	@qc: Command to complete
1269 *
1270 *	Indicate to the mid and upper layers that an ATA command has
1271 *	completed.  To be used from EH.
1272 */
1273void ata_eh_qc_complete(struct ata_queued_cmd *qc)
1274{
1275	struct scsi_cmnd *scmd = qc->scsicmd;
1276	scmd->retries = scmd->allowed;
1277	__ata_eh_qc_complete(qc);
1278}
1279
1280/**
1281 *	ata_eh_qc_retry - Tell midlayer to retry an ATA command after EH
1282 *	@qc: Command to retry
1283 *
1284 *	Indicate to the mid and upper layers that an ATA command
1285 *	should be retried.  To be used from EH.
1286 *
1287 *	SCSI midlayer limits the number of retries to scmd->allowed.
1288 *	scmd->retries is decremented for commands which get retried
1289 *	due to unrelated failures (qc->err_mask is zero).
1290 */
1291void ata_eh_qc_retry(struct ata_queued_cmd *qc)
1292{
1293	struct scsi_cmnd *scmd = qc->scsicmd;
1294	if (!qc->err_mask && scmd->retries)
1295		scmd->retries--;
1296	__ata_eh_qc_complete(qc);
1297}
1298
1299/**
1300 *	ata_dev_disable - disable ATA device
1301 *	@dev: ATA device to disable
1302 *
1303 *	Disable @dev.
1304 *
1305 *	Locking:
1306 *	EH context.
1307 */
1308void ata_dev_disable(struct ata_device *dev)
1309{
1310	if (!ata_dev_enabled(dev))
1311		return;
1312
1313	if (ata_msg_drv(dev->link->ap))
1314		ata_dev_warn(dev, "disabled\n");
1315	ata_acpi_on_disable(dev);
1316	ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 | ATA_DNXFER_QUIET);
1317	dev->class++;
1318
1319	/* From now till the next successful probe, ering is used to
1320	 * track probe failures.  Clear accumulated device error info.
1321	 */
1322	ata_ering_clear(&dev->ering);
1323}
 
1324
1325/**
1326 *	ata_eh_detach_dev - detach ATA device
1327 *	@dev: ATA device to detach
1328 *
1329 *	Detach @dev.
1330 *
1331 *	LOCKING:
1332 *	None.
1333 */
1334void ata_eh_detach_dev(struct ata_device *dev)
1335{
1336	struct ata_link *link = dev->link;
1337	struct ata_port *ap = link->ap;
1338	struct ata_eh_context *ehc = &link->eh_context;
1339	unsigned long flags;
1340
1341	ata_dev_disable(dev);
1342
1343	spin_lock_irqsave(ap->lock, flags);
1344
1345	dev->flags &= ~ATA_DFLAG_DETACH;
1346
1347	if (ata_scsi_offline_dev(dev)) {
1348		dev->flags |= ATA_DFLAG_DETACHED;
1349		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
1350	}
1351
1352	/* clear per-dev EH info */
1353	ata_eh_clear_action(link, dev, &link->eh_info, ATA_EH_PERDEV_MASK);
1354	ata_eh_clear_action(link, dev, &link->eh_context.i, ATA_EH_PERDEV_MASK);
1355	ehc->saved_xfer_mode[dev->devno] = 0;
1356	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
1357
1358	spin_unlock_irqrestore(ap->lock, flags);
1359}
1360
1361/**
1362 *	ata_eh_about_to_do - about to perform eh_action
1363 *	@link: target ATA link
1364 *	@dev: target ATA dev for per-dev action (can be NULL)
1365 *	@action: action about to be performed
1366 *
1367 *	Called just before performing EH actions to clear related bits
1368 *	in @link->eh_info such that eh actions are not unnecessarily
1369 *	repeated.
1370 *
1371 *	LOCKING:
1372 *	None.
1373 */
1374void ata_eh_about_to_do(struct ata_link *link, struct ata_device *dev,
1375			unsigned int action)
1376{
1377	struct ata_port *ap = link->ap;
1378	struct ata_eh_info *ehi = &link->eh_info;
1379	struct ata_eh_context *ehc = &link->eh_context;
1380	unsigned long flags;
1381
1382	spin_lock_irqsave(ap->lock, flags);
1383
1384	ata_eh_clear_action(link, dev, ehi, action);
1385
1386	/* About to take EH action, set RECOVERED.  Ignore actions on
1387	 * slave links as master will do them again.
1388	 */
1389	if (!(ehc->i.flags & ATA_EHI_QUIET) && link != ap->slave_link)
1390		ap->pflags |= ATA_PFLAG_RECOVERED;
1391
1392	spin_unlock_irqrestore(ap->lock, flags);
1393}
1394
1395/**
1396 *	ata_eh_done - EH action complete
1397*	@ap: target ATA port
1398 *	@dev: target ATA dev for per-dev action (can be NULL)
1399 *	@action: action just completed
1400 *
1401 *	Called right after performing EH actions to clear related bits
1402 *	in @link->eh_context.
1403 *
1404 *	LOCKING:
1405 *	None.
1406 */
1407void ata_eh_done(struct ata_link *link, struct ata_device *dev,
1408		 unsigned int action)
1409{
1410	struct ata_eh_context *ehc = &link->eh_context;
1411
1412	ata_eh_clear_action(link, dev, &ehc->i, action);
1413}
1414
1415/**
1416 *	ata_err_string - convert err_mask to descriptive string
1417 *	@err_mask: error mask to convert to string
1418 *
1419 *	Convert @err_mask to descriptive string.  Errors are
1420 *	prioritized according to severity and only the most severe
1421 *	error is reported.
1422 *
1423 *	LOCKING:
1424 *	None.
1425 *
1426 *	RETURNS:
1427 *	Descriptive string for @err_mask
1428 */
1429static const char *ata_err_string(unsigned int err_mask)
1430{
1431	if (err_mask & AC_ERR_HOST_BUS)
1432		return "host bus error";
1433	if (err_mask & AC_ERR_ATA_BUS)
1434		return "ATA bus error";
1435	if (err_mask & AC_ERR_TIMEOUT)
1436		return "timeout";
1437	if (err_mask & AC_ERR_HSM)
1438		return "HSM violation";
1439	if (err_mask & AC_ERR_SYSTEM)
1440		return "internal error";
1441	if (err_mask & AC_ERR_MEDIA)
1442		return "media error";
1443	if (err_mask & AC_ERR_INVALID)
1444		return "invalid argument";
1445	if (err_mask & AC_ERR_DEV)
1446		return "device error";
 
 
 
 
1447	return "unknown error";
1448}
1449
1450/**
1451 *	ata_read_log_page - read a specific log page
1452 *	@dev: target device
1453 *	@page: page to read
1454 *	@buf: buffer to store read page
1455 *	@sectors: number of sectors to read
1456 *
1457 *	Read log page using READ_LOG_EXT command.
1458 *
1459 *	LOCKING:
1460 *	Kernel thread context (may sleep).
1461 *
1462 *	RETURNS:
1463 *	0 on success, AC_ERR_* mask otherwise.
1464 */
1465static unsigned int ata_read_log_page(struct ata_device *dev,
1466				      u8 page, void *buf, unsigned int sectors)
1467{
 
1468	struct ata_taskfile tf;
1469	unsigned int err_mask;
1470
1471	DPRINTK("read log page - page %d\n", page);
1472
1473	ata_tf_init(dev, &tf);
1474	tf.command = ATA_CMD_READ_LOG_EXT;
1475	tf.lbal = page;
1476	tf.nsect = sectors;
1477	tf.hob_nsect = sectors >> 8;
1478	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_LBA48 | ATA_TFLAG_DEVICE;
1479	tf.protocol = ATA_PROT_PIO;
1480
1481	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_FROM_DEVICE,
1482				     buf, sectors * ATA_SECT_SIZE, 0);
 
1483
1484	DPRINTK("EXIT, err_mask=%x\n", err_mask);
 
 
1485	return err_mask;
1486}
1487
1488/**
1489 *	ata_eh_read_log_10h - Read log page 10h for NCQ error details
1490 *	@dev: Device to read log page 10h from
1491 *	@tag: Resulting tag of the failed command
1492 *	@tf: Resulting taskfile registers of the failed command
1493 *
1494 *	Read log page 10h to obtain NCQ error details and clear error
1495 *	condition.
1496 *
1497 *	LOCKING:
1498 *	Kernel thread context (may sleep).
1499 *
1500 *	RETURNS:
1501 *	0 on success, -errno otherwise.
1502 */
1503static int ata_eh_read_log_10h(struct ata_device *dev,
1504			       int *tag, struct ata_taskfile *tf)
1505{
1506	u8 *buf = dev->link->ap->sector_buf;
 
1507	unsigned int err_mask;
1508	u8 csum;
1509	int i;
1510
1511	err_mask = ata_read_log_page(dev, ATA_LOG_SATA_NCQ, buf, 1);
1512	if (err_mask)
1513		return -EIO;
1514
1515	csum = 0;
1516	for (i = 0; i < ATA_SECT_SIZE; i++)
1517		csum += buf[i];
1518	if (csum)
1519		ata_dev_warn(dev, "invalid checksum 0x%x on log page 10h\n",
1520			     csum);
1521
1522	if (buf[0] & 0x80)
1523		return -ENOENT;
1524
1525	*tag = buf[0] & 0x1f;
1526
1527	tf->command = buf[2];
1528	tf->feature = buf[3];
1529	tf->lbal = buf[4];
1530	tf->lbam = buf[5];
1531	tf->lbah = buf[6];
1532	tf->device = buf[7];
1533	tf->hob_lbal = buf[8];
1534	tf->hob_lbam = buf[9];
1535	tf->hob_lbah = buf[10];
1536	tf->nsect = buf[12];
1537	tf->hob_nsect = buf[13];
1538
1539	return 0;
1540}
 
 
1541
1542/**
1543 *	atapi_eh_tur - perform ATAPI TEST_UNIT_READY
1544 *	@dev: target ATAPI device
1545 *	@r_sense_key: out parameter for sense_key
1546 *
1547 *	Perform ATAPI TEST_UNIT_READY.
1548 *
1549 *	LOCKING:
1550 *	EH context (may sleep).
1551 *
1552 *	RETURNS:
1553 *	0 on success, AC_ERR_* mask on failure.
1554 */
1555static unsigned int atapi_eh_tur(struct ata_device *dev, u8 *r_sense_key)
1556{
1557	u8 cdb[ATAPI_CDB_LEN] = { TEST_UNIT_READY, 0, 0, 0, 0, 0 };
1558	struct ata_taskfile tf;
1559	unsigned int err_mask;
1560
1561	ata_tf_init(dev, &tf);
1562
1563	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1564	tf.command = ATA_CMD_PACKET;
1565	tf.protocol = ATAPI_PROT_NODATA;
 
1566
1567	err_mask = ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
1568	if (err_mask == AC_ERR_DEV)
1569		*r_sense_key = tf.feature >> 4;
1570	return err_mask;
 
 
 
 
 
1571}
1572
1573/**
1574 *	atapi_eh_request_sense - perform ATAPI REQUEST_SENSE
1575 *	@dev: device to perform REQUEST_SENSE to
1576 *	@sense_buf: result sense data buffer (SCSI_SENSE_BUFFERSIZE bytes long)
1577 *	@dfl_sense_key: default sense key to use
1578 *
1579 *	Perform ATAPI REQUEST_SENSE after the device reported CHECK
1580 *	SENSE.  This function is EH helper.
1581 *
1582 *	LOCKING:
1583 *	Kernel thread context (may sleep).
1584 *
1585 *	RETURNS:
1586 *	0 on success, AC_ERR_* mask on failure
1587 */
1588static unsigned int atapi_eh_request_sense(struct ata_device *dev,
1589					   u8 *sense_buf, u8 dfl_sense_key)
1590{
1591	u8 cdb[ATAPI_CDB_LEN] =
1592		{ REQUEST_SENSE, 0, 0, 0, SCSI_SENSE_BUFFERSIZE, 0 };
1593	struct ata_port *ap = dev->link->ap;
1594	struct ata_taskfile tf;
1595
1596	DPRINTK("ATAPI request sense\n");
1597
1598	/* FIXME: is this needed? */
1599	memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
1600
1601	/* initialize sense_buf with the error register,
1602	 * for the case where they are -not- overwritten
1603	 */
1604	sense_buf[0] = 0x70;
1605	sense_buf[2] = dfl_sense_key;
1606
1607	/* some devices time out if garbage left in tf */
1608	ata_tf_init(dev, &tf);
1609
1610	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1611	tf.command = ATA_CMD_PACKET;
1612
1613	/* is it pointless to prefer PIO for "safety reasons"? */
1614	if (ap->flags & ATA_FLAG_PIO_DMA) {
1615		tf.protocol = ATAPI_PROT_DMA;
1616		tf.feature |= ATAPI_PKT_DMA;
1617	} else {
1618		tf.protocol = ATAPI_PROT_PIO;
1619		tf.lbam = SCSI_SENSE_BUFFERSIZE;
1620		tf.lbah = 0;
1621	}
1622
1623	return ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
1624				 sense_buf, SCSI_SENSE_BUFFERSIZE, 0);
1625}
1626
1627/**
1628 *	ata_eh_analyze_serror - analyze SError for a failed port
1629 *	@link: ATA link to analyze SError for
1630 *
1631 *	Analyze SError if available and further determine cause of
1632 *	failure.
1633 *
1634 *	LOCKING:
1635 *	None.
1636 */
1637static void ata_eh_analyze_serror(struct ata_link *link)
1638{
1639	struct ata_eh_context *ehc = &link->eh_context;
1640	u32 serror = ehc->i.serror;
1641	unsigned int err_mask = 0, action = 0;
1642	u32 hotplug_mask;
1643
1644	if (serror & (SERR_PERSISTENT | SERR_DATA)) {
1645		err_mask |= AC_ERR_ATA_BUS;
1646		action |= ATA_EH_RESET;
1647	}
1648	if (serror & SERR_PROTOCOL) {
1649		err_mask |= AC_ERR_HSM;
1650		action |= ATA_EH_RESET;
1651	}
1652	if (serror & SERR_INTERNAL) {
1653		err_mask |= AC_ERR_SYSTEM;
1654		action |= ATA_EH_RESET;
1655	}
1656
1657	/* Determine whether a hotplug event has occurred.  Both
1658	 * SError.N/X are considered hotplug events for enabled or
1659	 * host links.  For disabled PMP links, only N bit is
1660	 * considered as X bit is left at 1 for link plugging.
1661	 */
1662	if (link->lpm_policy > ATA_LPM_MAX_POWER)
1663		hotplug_mask = 0;	/* hotplug doesn't work w/ LPM */
1664	else if (!(link->flags & ATA_LFLAG_DISABLED) || ata_is_host_link(link))
1665		hotplug_mask = SERR_PHYRDY_CHG | SERR_DEV_XCHG;
1666	else
1667		hotplug_mask = SERR_PHYRDY_CHG;
1668
1669	if (serror & hotplug_mask)
1670		ata_ehi_hotplugged(&ehc->i);
1671
1672	ehc->i.err_mask |= err_mask;
1673	ehc->i.action |= action;
1674}
1675
1676/**
1677 *	ata_eh_analyze_ncq_error - analyze NCQ error
1678 *	@link: ATA link to analyze NCQ error for
1679 *
1680 *	Read log page 10h, determine the offending qc and acquire
1681 *	error status TF.  For NCQ device errors, all LLDDs have to do
1682 *	is setting AC_ERR_DEV in ehi->err_mask.  This function takes
1683 *	care of the rest.
1684 *
1685 *	LOCKING:
1686 *	Kernel thread context (may sleep).
1687 */
1688void ata_eh_analyze_ncq_error(struct ata_link *link)
1689{
1690	struct ata_port *ap = link->ap;
1691	struct ata_eh_context *ehc = &link->eh_context;
1692	struct ata_device *dev = link->device;
1693	struct ata_queued_cmd *qc;
1694	struct ata_taskfile tf;
1695	int tag, rc;
1696
1697	/* if frozen, we can't do much */
1698	if (ap->pflags & ATA_PFLAG_FROZEN)
1699		return;
1700
1701	/* is it NCQ device error? */
1702	if (!link->sactive || !(ehc->i.err_mask & AC_ERR_DEV))
1703		return;
1704
1705	/* has LLDD analyzed already? */
1706	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
1707		qc = __ata_qc_from_tag(ap, tag);
1708
1709		if (!(qc->flags & ATA_QCFLAG_FAILED))
1710			continue;
1711
1712		if (qc->err_mask)
1713			return;
1714	}
1715
1716	/* okay, this error is ours */
1717	memset(&tf, 0, sizeof(tf));
1718	rc = ata_eh_read_log_10h(dev, &tag, &tf);
1719	if (rc) {
1720		ata_link_err(link, "failed to read log page 10h (errno=%d)\n",
1721			     rc);
1722		return;
1723	}
1724
1725	if (!(link->sactive & (1 << tag))) {
1726		ata_link_err(link, "log page 10h reported inactive tag %d\n",
1727			     tag);
1728		return;
1729	}
1730
1731	/* we've got the perpetrator, condemn it */
1732	qc = __ata_qc_from_tag(ap, tag);
1733	memcpy(&qc->result_tf, &tf, sizeof(tf));
1734	qc->result_tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
1735	qc->err_mask |= AC_ERR_DEV | AC_ERR_NCQ;
1736	ehc->i.err_mask &= ~AC_ERR_DEV;
1737}
1738
1739/**
1740 *	ata_eh_analyze_tf - analyze taskfile of a failed qc
1741 *	@qc: qc to analyze
1742 *	@tf: Taskfile registers to analyze
1743 *
1744 *	Analyze taskfile of @qc and further determine cause of
1745 *	failure.  This function also requests ATAPI sense data if
1746 *	available.
1747 *
1748 *	LOCKING:
1749 *	Kernel thread context (may sleep).
1750 *
1751 *	RETURNS:
1752 *	Determined recovery action
1753 */
1754static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc,
1755				      const struct ata_taskfile *tf)
1756{
1757	unsigned int tmp, action = 0;
1758	u8 stat = tf->command, err = tf->feature;
1759
1760	if ((stat & (ATA_BUSY | ATA_DRQ | ATA_DRDY)) != ATA_DRDY) {
1761		qc->err_mask |= AC_ERR_HSM;
1762		return ATA_EH_RESET;
1763	}
1764
1765	if (stat & (ATA_ERR | ATA_DF))
1766		qc->err_mask |= AC_ERR_DEV;
1767	else
 
 
 
 
 
 
1768		return 0;
 
1769
1770	switch (qc->dev->class) {
 
 
 
 
1771	case ATA_DEV_ATA:
1772		if (err & ATA_ICRC)
1773			qc->err_mask |= AC_ERR_ATA_BUS;
1774		if (err & ATA_UNC)
1775			qc->err_mask |= AC_ERR_MEDIA;
1776		if (err & ATA_IDNF)
1777			qc->err_mask |= AC_ERR_INVALID;
1778		break;
1779
1780	case ATA_DEV_ATAPI:
1781		if (!(qc->ap->pflags & ATA_PFLAG_FROZEN)) {
1782			tmp = atapi_eh_request_sense(qc->dev,
1783						qc->scsicmd->sense_buffer,
1784						qc->result_tf.feature >> 4);
1785			if (!tmp) {
1786				/* ATA_QCFLAG_SENSE_VALID is used to
1787				 * tell atapi_qc_complete() that sense
1788				 * data is already valid.
1789				 *
1790				 * TODO: interpret sense data and set
1791				 * appropriate err_mask.
1792				 */
1793				qc->flags |= ATA_QCFLAG_SENSE_VALID;
1794			} else
1795				qc->err_mask |= tmp;
1796		}
1797	}
1798
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1799	if (qc->err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT | AC_ERR_ATA_BUS))
1800		action |= ATA_EH_RESET;
1801
1802	return action;
1803}
1804
1805static int ata_eh_categorize_error(unsigned int eflags, unsigned int err_mask,
1806				   int *xfer_ok)
1807{
1808	int base = 0;
1809
1810	if (!(eflags & ATA_EFLAG_DUBIOUS_XFER))
1811		*xfer_ok = 1;
1812
1813	if (!*xfer_ok)
1814		base = ATA_ECAT_DUBIOUS_NONE;
1815
1816	if (err_mask & AC_ERR_ATA_BUS)
1817		return base + ATA_ECAT_ATA_BUS;
1818
1819	if (err_mask & AC_ERR_TIMEOUT)
1820		return base + ATA_ECAT_TOUT_HSM;
1821
1822	if (eflags & ATA_EFLAG_IS_IO) {
1823		if (err_mask & AC_ERR_HSM)
1824			return base + ATA_ECAT_TOUT_HSM;
1825		if ((err_mask &
1826		     (AC_ERR_DEV|AC_ERR_MEDIA|AC_ERR_INVALID)) == AC_ERR_DEV)
1827			return base + ATA_ECAT_UNK_DEV;
1828	}
1829
1830	return 0;
1831}
1832
1833struct speed_down_verdict_arg {
1834	u64 since;
1835	int xfer_ok;
1836	int nr_errors[ATA_ECAT_NR];
1837};
1838
1839static int speed_down_verdict_cb(struct ata_ering_entry *ent, void *void_arg)
1840{
1841	struct speed_down_verdict_arg *arg = void_arg;
1842	int cat;
1843
1844	if ((ent->eflags & ATA_EFLAG_OLD_ER) || (ent->timestamp < arg->since))
1845		return -1;
1846
1847	cat = ata_eh_categorize_error(ent->eflags, ent->err_mask,
1848				      &arg->xfer_ok);
1849	arg->nr_errors[cat]++;
1850
1851	return 0;
1852}
1853
1854/**
1855 *	ata_eh_speed_down_verdict - Determine speed down verdict
1856 *	@dev: Device of interest
1857 *
1858 *	This function examines error ring of @dev and determines
1859 *	whether NCQ needs to be turned off, transfer speed should be
1860 *	stepped down, or falling back to PIO is necessary.
1861 *
1862 *	ECAT_ATA_BUS	: ATA_BUS error for any command
1863 *
1864 *	ECAT_TOUT_HSM	: TIMEOUT for any command or HSM violation for
1865 *			  IO commands
1866 *
1867 *	ECAT_UNK_DEV	: Unknown DEV error for IO commands
1868 *
1869 *	ECAT_DUBIOUS_*	: Identical to above three but occurred while
1870 *			  data transfer hasn't been verified.
1871 *
1872 *	Verdicts are
1873 *
1874 *	NCQ_OFF		: Turn off NCQ.
1875 *
1876 *	SPEED_DOWN	: Speed down transfer speed but don't fall back
1877 *			  to PIO.
1878 *
1879 *	FALLBACK_TO_PIO	: Fall back to PIO.
1880 *
1881 *	Even if multiple verdicts are returned, only one action is
1882 *	taken per error.  An action triggered by non-DUBIOUS errors
1883 *	clears ering, while one triggered by DUBIOUS_* errors doesn't.
1884 *	This is to expedite speed down decisions right after device is
1885 *	initially configured.
1886 *
1887 *	The followings are speed down rules.  #1 and #2 deal with
1888 *	DUBIOUS errors.
1889 *
1890 *	1. If more than one DUBIOUS_ATA_BUS or DUBIOUS_TOUT_HSM errors
1891 *	   occurred during last 5 mins, SPEED_DOWN and FALLBACK_TO_PIO.
1892 *
1893 *	2. If more than one DUBIOUS_TOUT_HSM or DUBIOUS_UNK_DEV errors
1894 *	   occurred during last 5 mins, NCQ_OFF.
1895 *
1896 *	3. If more than 8 ATA_BUS, TOUT_HSM or UNK_DEV errors
1897 *	   occurred during last 5 mins, FALLBACK_TO_PIO
1898 *
1899 *	4. If more than 3 TOUT_HSM or UNK_DEV errors occurred
1900 *	   during last 10 mins, NCQ_OFF.
1901 *
1902 *	5. If more than 3 ATA_BUS or TOUT_HSM errors, or more than 6
1903 *	   UNK_DEV errors occurred during last 10 mins, SPEED_DOWN.
1904 *
1905 *	LOCKING:
1906 *	Inherited from caller.
1907 *
1908 *	RETURNS:
1909 *	OR of ATA_EH_SPDN_* flags.
1910 */
1911static unsigned int ata_eh_speed_down_verdict(struct ata_device *dev)
1912{
1913	const u64 j5mins = 5LLU * 60 * HZ, j10mins = 10LLU * 60 * HZ;
1914	u64 j64 = get_jiffies_64();
1915	struct speed_down_verdict_arg arg;
1916	unsigned int verdict = 0;
1917
1918	/* scan past 5 mins of error history */
1919	memset(&arg, 0, sizeof(arg));
1920	arg.since = j64 - min(j64, j5mins);
1921	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1922
1923	if (arg.nr_errors[ATA_ECAT_DUBIOUS_ATA_BUS] +
1924	    arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] > 1)
1925		verdict |= ATA_EH_SPDN_SPEED_DOWN |
1926			ATA_EH_SPDN_FALLBACK_TO_PIO | ATA_EH_SPDN_KEEP_ERRORS;
1927
1928	if (arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] +
1929	    arg.nr_errors[ATA_ECAT_DUBIOUS_UNK_DEV] > 1)
1930		verdict |= ATA_EH_SPDN_NCQ_OFF | ATA_EH_SPDN_KEEP_ERRORS;
1931
1932	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1933	    arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1934	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1935		verdict |= ATA_EH_SPDN_FALLBACK_TO_PIO;
1936
1937	/* scan past 10 mins of error history */
1938	memset(&arg, 0, sizeof(arg));
1939	arg.since = j64 - min(j64, j10mins);
1940	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1941
1942	if (arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1943	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 3)
1944		verdict |= ATA_EH_SPDN_NCQ_OFF;
1945
1946	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1947	    arg.nr_errors[ATA_ECAT_TOUT_HSM] > 3 ||
1948	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
1949		verdict |= ATA_EH_SPDN_SPEED_DOWN;
1950
1951	return verdict;
1952}
1953
1954/**
1955 *	ata_eh_speed_down - record error and speed down if necessary
1956 *	@dev: Failed device
1957 *	@eflags: mask of ATA_EFLAG_* flags
1958 *	@err_mask: err_mask of the error
1959 *
1960 *	Record error and examine error history to determine whether
1961 *	adjusting transmission speed is necessary.  It also sets
1962 *	transmission limits appropriately if such adjustment is
1963 *	necessary.
1964 *
1965 *	LOCKING:
1966 *	Kernel thread context (may sleep).
1967 *
1968 *	RETURNS:
1969 *	Determined recovery action.
1970 */
1971static unsigned int ata_eh_speed_down(struct ata_device *dev,
1972				unsigned int eflags, unsigned int err_mask)
1973{
1974	struct ata_link *link = ata_dev_phys_link(dev);
1975	int xfer_ok = 0;
1976	unsigned int verdict;
1977	unsigned int action = 0;
1978
1979	/* don't bother if Cat-0 error */
1980	if (ata_eh_categorize_error(eflags, err_mask, &xfer_ok) == 0)
1981		return 0;
1982
1983	/* record error and determine whether speed down is necessary */
1984	ata_ering_record(&dev->ering, eflags, err_mask);
1985	verdict = ata_eh_speed_down_verdict(dev);
1986
1987	/* turn off NCQ? */
1988	if ((verdict & ATA_EH_SPDN_NCQ_OFF) &&
1989	    (dev->flags & (ATA_DFLAG_PIO | ATA_DFLAG_NCQ |
1990			   ATA_DFLAG_NCQ_OFF)) == ATA_DFLAG_NCQ) {
1991		dev->flags |= ATA_DFLAG_NCQ_OFF;
1992		ata_dev_warn(dev, "NCQ disabled due to excessive errors\n");
1993		goto done;
1994	}
1995
1996	/* speed down? */
1997	if (verdict & ATA_EH_SPDN_SPEED_DOWN) {
1998		/* speed down SATA link speed if possible */
1999		if (sata_down_spd_limit(link, 0) == 0) {
2000			action |= ATA_EH_RESET;
2001			goto done;
2002		}
2003
2004		/* lower transfer mode */
2005		if (dev->spdn_cnt < 2) {
2006			static const int dma_dnxfer_sel[] =
2007				{ ATA_DNXFER_DMA, ATA_DNXFER_40C };
2008			static const int pio_dnxfer_sel[] =
2009				{ ATA_DNXFER_PIO, ATA_DNXFER_FORCE_PIO0 };
2010			int sel;
2011
2012			if (dev->xfer_shift != ATA_SHIFT_PIO)
2013				sel = dma_dnxfer_sel[dev->spdn_cnt];
2014			else
2015				sel = pio_dnxfer_sel[dev->spdn_cnt];
2016
2017			dev->spdn_cnt++;
2018
2019			if (ata_down_xfermask_limit(dev, sel) == 0) {
2020				action |= ATA_EH_RESET;
2021				goto done;
2022			}
2023		}
2024	}
2025
2026	/* Fall back to PIO?  Slowing down to PIO is meaningless for
2027	 * SATA ATA devices.  Consider it only for PATA and SATAPI.
2028	 */
2029	if ((verdict & ATA_EH_SPDN_FALLBACK_TO_PIO) && (dev->spdn_cnt >= 2) &&
2030	    (link->ap->cbl != ATA_CBL_SATA || dev->class == ATA_DEV_ATAPI) &&
2031	    (dev->xfer_shift != ATA_SHIFT_PIO)) {
2032		if (ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO) == 0) {
2033			dev->spdn_cnt = 0;
2034			action |= ATA_EH_RESET;
2035			goto done;
2036		}
2037	}
2038
2039	return 0;
2040 done:
2041	/* device has been slowed down, blow error history */
2042	if (!(verdict & ATA_EH_SPDN_KEEP_ERRORS))
2043		ata_ering_clear(&dev->ering);
2044	return action;
2045}
2046
2047/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2048 *	ata_eh_link_autopsy - analyze error and determine recovery action
2049 *	@link: host link to perform autopsy on
2050 *
2051 *	Analyze why @link failed and determine which recovery actions
2052 *	are needed.  This function also sets more detailed AC_ERR_*
2053 *	values and fills sense data for ATAPI CHECK SENSE.
2054 *
2055 *	LOCKING:
2056 *	Kernel thread context (may sleep).
2057 */
2058static void ata_eh_link_autopsy(struct ata_link *link)
2059{
2060	struct ata_port *ap = link->ap;
2061	struct ata_eh_context *ehc = &link->eh_context;
 
2062	struct ata_device *dev;
2063	unsigned int all_err_mask = 0, eflags = 0;
2064	int tag;
2065	u32 serror;
2066	int rc;
2067
2068	DPRINTK("ENTER\n");
2069
2070	if (ehc->i.flags & ATA_EHI_NO_AUTOPSY)
2071		return;
2072
2073	/* obtain and analyze SError */
2074	rc = sata_scr_read(link, SCR_ERROR, &serror);
2075	if (rc == 0) {
2076		ehc->i.serror |= serror;
2077		ata_eh_analyze_serror(link);
2078	} else if (rc != -EOPNOTSUPP) {
2079		/* SError read failed, force reset and probing */
2080		ehc->i.probe_mask |= ATA_ALL_DEVICES;
2081		ehc->i.action |= ATA_EH_RESET;
2082		ehc->i.err_mask |= AC_ERR_OTHER;
2083	}
2084
2085	/* analyze NCQ failure */
2086	ata_eh_analyze_ncq_error(link);
2087
2088	/* any real error trumps AC_ERR_OTHER */
2089	if (ehc->i.err_mask & ~AC_ERR_OTHER)
2090		ehc->i.err_mask &= ~AC_ERR_OTHER;
2091
2092	all_err_mask |= ehc->i.err_mask;
2093
2094	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
2095		struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
2096
2097		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2098		    ata_dev_phys_link(qc->dev) != link)
2099			continue;
2100
2101		/* inherit upper level err_mask */
2102		qc->err_mask |= ehc->i.err_mask;
2103
2104		/* analyze TF */
2105		ehc->i.action |= ata_eh_analyze_tf(qc, &qc->result_tf);
2106
2107		/* DEV errors are probably spurious in case of ATA_BUS error */
2108		if (qc->err_mask & AC_ERR_ATA_BUS)
2109			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_MEDIA |
2110					  AC_ERR_INVALID);
2111
2112		/* any real error trumps unknown error */
2113		if (qc->err_mask & ~AC_ERR_OTHER)
2114			qc->err_mask &= ~AC_ERR_OTHER;
2115
2116		/* SENSE_VALID trumps dev/unknown error and revalidation */
 
 
 
 
 
 
2117		if (qc->flags & ATA_QCFLAG_SENSE_VALID)
2118			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_OTHER);
2119
2120		/* determine whether the command is worth retrying */
2121		if (qc->flags & ATA_QCFLAG_IO ||
2122		    (!(qc->err_mask & AC_ERR_INVALID) &&
2123		     qc->err_mask != AC_ERR_DEV))
2124			qc->flags |= ATA_QCFLAG_RETRY;
2125
2126		/* accumulate error info */
2127		ehc->i.dev = qc->dev;
2128		all_err_mask |= qc->err_mask;
2129		if (qc->flags & ATA_QCFLAG_IO)
2130			eflags |= ATA_EFLAG_IS_IO;
 
 
 
 
 
 
2131	}
2132
 
 
 
 
2133	/* enforce default EH actions */
2134	if (ap->pflags & ATA_PFLAG_FROZEN ||
2135	    all_err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT))
2136		ehc->i.action |= ATA_EH_RESET;
2137	else if (((eflags & ATA_EFLAG_IS_IO) && all_err_mask) ||
2138		 (!(eflags & ATA_EFLAG_IS_IO) && (all_err_mask & ~AC_ERR_DEV)))
2139		ehc->i.action |= ATA_EH_REVALIDATE;
2140
2141	/* If we have offending qcs and the associated failed device,
2142	 * perform per-dev EH action only on the offending device.
2143	 */
2144	if (ehc->i.dev) {
2145		ehc->i.dev_action[ehc->i.dev->devno] |=
2146			ehc->i.action & ATA_EH_PERDEV_MASK;
2147		ehc->i.action &= ~ATA_EH_PERDEV_MASK;
2148	}
2149
2150	/* propagate timeout to host link */
2151	if ((all_err_mask & AC_ERR_TIMEOUT) && !ata_is_host_link(link))
2152		ap->link.eh_context.i.err_mask |= AC_ERR_TIMEOUT;
2153
2154	/* record error and consider speeding down */
2155	dev = ehc->i.dev;
2156	if (!dev && ((ata_link_max_devices(link) == 1 &&
2157		      ata_dev_enabled(link->device))))
2158	    dev = link->device;
2159
2160	if (dev) {
2161		if (dev->flags & ATA_DFLAG_DUBIOUS_XFER)
2162			eflags |= ATA_EFLAG_DUBIOUS_XFER;
2163		ehc->i.action |= ata_eh_speed_down(dev, eflags, all_err_mask);
 
2164	}
2165
2166	DPRINTK("EXIT\n");
2167}
2168
2169/**
2170 *	ata_eh_autopsy - analyze error and determine recovery action
2171 *	@ap: host port to perform autopsy on
2172 *
2173 *	Analyze all links of @ap and determine why they failed and
2174 *	which recovery actions are needed.
2175 *
2176 *	LOCKING:
2177 *	Kernel thread context (may sleep).
2178 */
2179void ata_eh_autopsy(struct ata_port *ap)
2180{
2181	struct ata_link *link;
2182
2183	ata_for_each_link(link, ap, EDGE)
2184		ata_eh_link_autopsy(link);
2185
2186	/* Handle the frigging slave link.  Autopsy is done similarly
2187	 * but actions and flags are transferred over to the master
2188	 * link and handled from there.
2189	 */
2190	if (ap->slave_link) {
2191		struct ata_eh_context *mehc = &ap->link.eh_context;
2192		struct ata_eh_context *sehc = &ap->slave_link->eh_context;
2193
2194		/* transfer control flags from master to slave */
2195		sehc->i.flags |= mehc->i.flags & ATA_EHI_TO_SLAVE_MASK;
2196
2197		/* perform autopsy on the slave link */
2198		ata_eh_link_autopsy(ap->slave_link);
2199
2200		/* transfer actions from slave to master and clear slave */
2201		ata_eh_about_to_do(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2202		mehc->i.action		|= sehc->i.action;
2203		mehc->i.dev_action[1]	|= sehc->i.dev_action[1];
2204		mehc->i.flags		|= sehc->i.flags;
2205		ata_eh_done(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2206	}
2207
2208	/* Autopsy of fanout ports can affect host link autopsy.
2209	 * Perform host link autopsy last.
2210	 */
2211	if (sata_pmp_attached(ap))
2212		ata_eh_link_autopsy(&ap->link);
2213}
2214
2215/**
2216 *	ata_get_cmd_descript - get description for ATA command
2217 *	@command: ATA command code to get description for
2218 *
2219 *	Return a textual description of the given command, or NULL if the
2220 *	command is not known.
2221 *
2222 *	LOCKING:
2223 *	None
2224 */
2225const char *ata_get_cmd_descript(u8 command)
2226{
2227#ifdef CONFIG_ATA_VERBOSE_ERROR
2228	static const struct
2229	{
2230		u8 command;
2231		const char *text;
2232	} cmd_descr[] = {
2233		{ ATA_CMD_DEV_RESET,		"DEVICE RESET" },
2234		{ ATA_CMD_CHK_POWER, 		"CHECK POWER MODE" },
2235		{ ATA_CMD_STANDBY, 		"STANDBY" },
2236		{ ATA_CMD_IDLE, 		"IDLE" },
2237		{ ATA_CMD_EDD, 			"EXECUTE DEVICE DIAGNOSTIC" },
2238		{ ATA_CMD_DOWNLOAD_MICRO,   	"DOWNLOAD MICROCODE" },
 
2239		{ ATA_CMD_NOP,			"NOP" },
2240		{ ATA_CMD_FLUSH, 		"FLUSH CACHE" },
2241		{ ATA_CMD_FLUSH_EXT, 		"FLUSH CACHE EXT" },
2242		{ ATA_CMD_ID_ATA,  		"IDENTIFY DEVICE" },
2243		{ ATA_CMD_ID_ATAPI, 		"IDENTIFY PACKET DEVICE" },
2244		{ ATA_CMD_SERVICE, 		"SERVICE" },
2245		{ ATA_CMD_READ, 		"READ DMA" },
2246		{ ATA_CMD_READ_EXT, 		"READ DMA EXT" },
2247		{ ATA_CMD_READ_QUEUED, 		"READ DMA QUEUED" },
2248		{ ATA_CMD_READ_STREAM_EXT, 	"READ STREAM EXT" },
2249		{ ATA_CMD_READ_STREAM_DMA_EXT,  "READ STREAM DMA EXT" },
2250		{ ATA_CMD_WRITE, 		"WRITE DMA" },
2251		{ ATA_CMD_WRITE_EXT, 		"WRITE DMA EXT" },
2252		{ ATA_CMD_WRITE_QUEUED, 	"WRITE DMA QUEUED EXT" },
2253		{ ATA_CMD_WRITE_STREAM_EXT, 	"WRITE STREAM EXT" },
2254		{ ATA_CMD_WRITE_STREAM_DMA_EXT, "WRITE STREAM DMA EXT" },
2255		{ ATA_CMD_WRITE_FUA_EXT,	"WRITE DMA FUA EXT" },
2256		{ ATA_CMD_WRITE_QUEUED_FUA_EXT, "WRITE DMA QUEUED FUA EXT" },
2257		{ ATA_CMD_FPDMA_READ,		"READ FPDMA QUEUED" },
2258		{ ATA_CMD_FPDMA_WRITE,		"WRITE FPDMA QUEUED" },
 
 
2259		{ ATA_CMD_PIO_READ,		"READ SECTOR(S)" },
2260		{ ATA_CMD_PIO_READ_EXT,		"READ SECTOR(S) EXT" },
2261		{ ATA_CMD_PIO_WRITE,		"WRITE SECTOR(S)" },
2262		{ ATA_CMD_PIO_WRITE_EXT,	"WRITE SECTOR(S) EXT" },
2263		{ ATA_CMD_READ_MULTI,		"READ MULTIPLE" },
2264		{ ATA_CMD_READ_MULTI_EXT,	"READ MULTIPLE EXT" },
2265		{ ATA_CMD_WRITE_MULTI,		"WRITE MULTIPLE" },
2266		{ ATA_CMD_WRITE_MULTI_EXT,	"WRITE MULTIPLE EXT" },
2267		{ ATA_CMD_WRITE_MULTI_FUA_EXT, 	"WRITE MULTIPLE FUA EXT" },
2268		{ ATA_CMD_SET_FEATURES,		"SET FEATURES" },
2269		{ ATA_CMD_SET_MULTI,		"SET MULTIPLE MODE" },
2270		{ ATA_CMD_VERIFY,		"READ VERIFY SECTOR(S)" },
2271		{ ATA_CMD_VERIFY_EXT,		"READ VERIFY SECTOR(S) EXT" },
2272		{ ATA_CMD_WRITE_UNCORR_EXT,	"WRITE UNCORRECTABLE EXT" },
2273		{ ATA_CMD_STANDBYNOW1,		"STANDBY IMMEDIATE" },
2274		{ ATA_CMD_IDLEIMMEDIATE,	"IDLE IMMEDIATE" },
2275		{ ATA_CMD_SLEEP,		"SLEEP" },
2276		{ ATA_CMD_INIT_DEV_PARAMS,	"INITIALIZE DEVICE PARAMETERS" },
2277		{ ATA_CMD_READ_NATIVE_MAX,	"READ NATIVE MAX ADDRESS" },
2278		{ ATA_CMD_READ_NATIVE_MAX_EXT,	"READ NATIVE MAX ADDRESS EXT" },
2279		{ ATA_CMD_SET_MAX,		"SET MAX ADDRESS" },
2280		{ ATA_CMD_SET_MAX_EXT,		"SET MAX ADDRESS EXT" },
2281		{ ATA_CMD_READ_LOG_EXT,		"READ LOG EXT" },
2282		{ ATA_CMD_WRITE_LOG_EXT,	"WRITE LOG EXT" },
2283		{ ATA_CMD_READ_LOG_DMA_EXT,	"READ LOG DMA EXT" },
2284		{ ATA_CMD_WRITE_LOG_DMA_EXT, 	"WRITE LOG DMA EXT" },
 
2285		{ ATA_CMD_TRUSTED_RCV,		"TRUSTED RECEIVE" },
2286		{ ATA_CMD_TRUSTED_RCV_DMA, 	"TRUSTED RECEIVE DMA" },
2287		{ ATA_CMD_TRUSTED_SND,		"TRUSTED SEND" },
2288		{ ATA_CMD_TRUSTED_SND_DMA, 	"TRUSTED SEND DMA" },
2289		{ ATA_CMD_PMP_READ,		"READ BUFFER" },
 
2290		{ ATA_CMD_PMP_WRITE,		"WRITE BUFFER" },
 
2291		{ ATA_CMD_CONF_OVERLAY,		"DEVICE CONFIGURATION OVERLAY" },
2292		{ ATA_CMD_SEC_SET_PASS,		"SECURITY SET PASSWORD" },
2293		{ ATA_CMD_SEC_UNLOCK,		"SECURITY UNLOCK" },
2294		{ ATA_CMD_SEC_ERASE_PREP,	"SECURITY ERASE PREPARE" },
2295		{ ATA_CMD_SEC_ERASE_UNIT,	"SECURITY ERASE UNIT" },
2296		{ ATA_CMD_SEC_FREEZE_LOCK,	"SECURITY FREEZE LOCK" },
2297		{ ATA_CMD_SEC_DISABLE_PASS,	"SECURITY DISABLE PASSWORD" },
2298		{ ATA_CMD_CONFIG_STREAM,	"CONFIGURE STREAM" },
2299		{ ATA_CMD_SMART,		"SMART" },
2300		{ ATA_CMD_MEDIA_LOCK,		"DOOR LOCK" },
2301		{ ATA_CMD_MEDIA_UNLOCK,		"DOOR UNLOCK" },
2302		{ ATA_CMD_DSM,			"DATA SET MANAGEMENT" },
2303		{ ATA_CMD_CHK_MED_CRD_TYP, 	"CHECK MEDIA CARD TYPE" },
2304		{ ATA_CMD_CFA_REQ_EXT_ERR, 	"CFA REQUEST EXTENDED ERROR" },
2305		{ ATA_CMD_CFA_WRITE_NE,		"CFA WRITE SECTORS WITHOUT ERASE" },
2306		{ ATA_CMD_CFA_TRANS_SECT,	"CFA TRANSLATE SECTOR" },
2307		{ ATA_CMD_CFA_ERASE,		"CFA ERASE SECTORS" },
2308		{ ATA_CMD_CFA_WRITE_MULT_NE, 	"CFA WRITE MULTIPLE WITHOUT ERASE" },
 
 
 
 
2309		{ ATA_CMD_READ_LONG,		"READ LONG (with retries)" },
2310		{ ATA_CMD_READ_LONG_ONCE,	"READ LONG (without retries)" },
2311		{ ATA_CMD_WRITE_LONG,		"WRITE LONG (with retries)" },
2312		{ ATA_CMD_WRITE_LONG_ONCE,	"WRITE LONG (without retries)" },
2313		{ ATA_CMD_RESTORE,		"RECALIBRATE" },
2314		{ 0,				NULL } /* terminate list */
2315	};
2316
2317	unsigned int i;
2318	for (i = 0; cmd_descr[i].text; i++)
2319		if (cmd_descr[i].command == command)
2320			return cmd_descr[i].text;
2321#endif
2322
2323	return NULL;
2324}
 
2325
2326/**
2327 *	ata_eh_link_report - report error handling to user
2328 *	@link: ATA link EH is going on
2329 *
2330 *	Report EH to user.
2331 *
2332 *	LOCKING:
2333 *	None.
2334 */
2335static void ata_eh_link_report(struct ata_link *link)
2336{
2337	struct ata_port *ap = link->ap;
2338	struct ata_eh_context *ehc = &link->eh_context;
 
2339	const char *frozen, *desc;
2340	char tries_buf[6];
2341	int tag, nr_failed = 0;
2342
2343	if (ehc->i.flags & ATA_EHI_QUIET)
2344		return;
2345
2346	desc = NULL;
2347	if (ehc->i.desc[0] != '\0')
2348		desc = ehc->i.desc;
2349
2350	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
2351		struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
2352
2353		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2354		    ata_dev_phys_link(qc->dev) != link ||
2355		    ((qc->flags & ATA_QCFLAG_QUIET) &&
2356		     qc->err_mask == AC_ERR_DEV))
2357			continue;
2358		if (qc->flags & ATA_QCFLAG_SENSE_VALID && !qc->err_mask)
2359			continue;
2360
2361		nr_failed++;
2362	}
2363
2364	if (!nr_failed && !ehc->i.err_mask)
2365		return;
2366
2367	frozen = "";
2368	if (ap->pflags & ATA_PFLAG_FROZEN)
2369		frozen = " frozen";
2370
2371	memset(tries_buf, 0, sizeof(tries_buf));
2372	if (ap->eh_tries < ATA_EH_MAX_TRIES)
2373		snprintf(tries_buf, sizeof(tries_buf) - 1, " t%d",
2374			 ap->eh_tries);
2375
2376	if (ehc->i.dev) {
2377		ata_dev_err(ehc->i.dev, "exception Emask 0x%x "
2378			    "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2379			    ehc->i.err_mask, link->sactive, ehc->i.serror,
2380			    ehc->i.action, frozen, tries_buf);
2381		if (desc)
2382			ata_dev_err(ehc->i.dev, "%s\n", desc);
2383	} else {
2384		ata_link_err(link, "exception Emask 0x%x "
2385			     "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2386			     ehc->i.err_mask, link->sactive, ehc->i.serror,
2387			     ehc->i.action, frozen, tries_buf);
2388		if (desc)
2389			ata_link_err(link, "%s\n", desc);
2390	}
2391
2392#ifdef CONFIG_ATA_VERBOSE_ERROR
2393	if (ehc->i.serror)
2394		ata_link_err(link,
2395		  "SError: { %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s}\n",
2396		  ehc->i.serror & SERR_DATA_RECOVERED ? "RecovData " : "",
2397		  ehc->i.serror & SERR_COMM_RECOVERED ? "RecovComm " : "",
2398		  ehc->i.serror & SERR_DATA ? "UnrecovData " : "",
2399		  ehc->i.serror & SERR_PERSISTENT ? "Persist " : "",
2400		  ehc->i.serror & SERR_PROTOCOL ? "Proto " : "",
2401		  ehc->i.serror & SERR_INTERNAL ? "HostInt " : "",
2402		  ehc->i.serror & SERR_PHYRDY_CHG ? "PHYRdyChg " : "",
2403		  ehc->i.serror & SERR_PHY_INT_ERR ? "PHYInt " : "",
2404		  ehc->i.serror & SERR_COMM_WAKE ? "CommWake " : "",
2405		  ehc->i.serror & SERR_10B_8B_ERR ? "10B8B " : "",
2406		  ehc->i.serror & SERR_DISPARITY ? "Dispar " : "",
2407		  ehc->i.serror & SERR_CRC ? "BadCRC " : "",
2408		  ehc->i.serror & SERR_HANDSHAKE ? "Handshk " : "",
2409		  ehc->i.serror & SERR_LINK_SEQ_ERR ? "LinkSeq " : "",
2410		  ehc->i.serror & SERR_TRANS_ST_ERROR ? "TrStaTrns " : "",
2411		  ehc->i.serror & SERR_UNRECOG_FIS ? "UnrecFIS " : "",
2412		  ehc->i.serror & SERR_DEV_XCHG ? "DevExch " : "");
2413#endif
2414
2415	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
2416		struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
2417		struct ata_taskfile *cmd = &qc->tf, *res = &qc->result_tf;
2418		const u8 *cdb = qc->cdb;
2419		char data_buf[20] = "";
2420		char cdb_buf[70] = "";
2421
2422		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2423		    ata_dev_phys_link(qc->dev) != link || !qc->err_mask)
2424			continue;
2425
2426		if (qc->dma_dir != DMA_NONE) {
2427			static const char *dma_str[] = {
2428				[DMA_BIDIRECTIONAL]	= "bidi",
2429				[DMA_TO_DEVICE]		= "out",
2430				[DMA_FROM_DEVICE]	= "in",
2431			};
2432			static const char *prot_str[] = {
2433				[ATA_PROT_PIO]		= "pio",
2434				[ATA_PROT_DMA]		= "dma",
2435				[ATA_PROT_NCQ]		= "ncq",
2436				[ATAPI_PROT_PIO]	= "pio",
2437				[ATAPI_PROT_DMA]	= "dma",
2438			};
2439
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2440			snprintf(data_buf, sizeof(data_buf), " %s %u %s",
2441				 prot_str[qc->tf.protocol], qc->nbytes,
2442				 dma_str[qc->dma_dir]);
2443		}
2444
2445		if (ata_is_atapi(qc->tf.protocol)) {
2446			if (qc->scsicmd)
2447				scsi_print_command(qc->scsicmd);
2448			else
2449				snprintf(cdb_buf, sizeof(cdb_buf),
2450				 "cdb %02x %02x %02x %02x %02x %02x %02x %02x  "
2451				 "%02x %02x %02x %02x %02x %02x %02x %02x\n         ",
2452				 cdb[0], cdb[1], cdb[2], cdb[3],
2453				 cdb[4], cdb[5], cdb[6], cdb[7],
2454				 cdb[8], cdb[9], cdb[10], cdb[11],
2455				 cdb[12], cdb[13], cdb[14], cdb[15]);
2456		} else {
2457			const char *descr = ata_get_cmd_descript(cmd->command);
2458			if (descr)
2459				ata_dev_err(qc->dev, "failed command: %s\n",
2460					    descr);
2461		}
2462
2463		ata_dev_err(qc->dev,
2464			"cmd %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2465			"tag %d%s\n         %s"
2466			"res %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2467			"Emask 0x%x (%s)%s\n",
2468			cmd->command, cmd->feature, cmd->nsect,
2469			cmd->lbal, cmd->lbam, cmd->lbah,
2470			cmd->hob_feature, cmd->hob_nsect,
2471			cmd->hob_lbal, cmd->hob_lbam, cmd->hob_lbah,
2472			cmd->device, qc->tag, data_buf, cdb_buf,
2473			res->command, res->feature, res->nsect,
2474			res->lbal, res->lbam, res->lbah,
2475			res->hob_feature, res->hob_nsect,
2476			res->hob_lbal, res->hob_lbam, res->hob_lbah,
2477			res->device, qc->err_mask, ata_err_string(qc->err_mask),
2478			qc->err_mask & AC_ERR_NCQ ? " <F>" : "");
2479
2480#ifdef CONFIG_ATA_VERBOSE_ERROR
2481		if (res->command & (ATA_BUSY | ATA_DRDY | ATA_DF | ATA_DRQ |
2482				    ATA_ERR)) {
2483			if (res->command & ATA_BUSY)
2484				ata_dev_err(qc->dev, "status: { Busy }\n");
2485			else
2486				ata_dev_err(qc->dev, "status: { %s%s%s%s}\n",
2487				  res->command & ATA_DRDY ? "DRDY " : "",
2488				  res->command & ATA_DF ? "DF " : "",
2489				  res->command & ATA_DRQ ? "DRQ " : "",
 
2490				  res->command & ATA_ERR ? "ERR " : "");
2491		}
2492
2493		if (cmd->command != ATA_CMD_PACKET &&
2494		    (res->feature & (ATA_ICRC | ATA_UNC | ATA_IDNF |
2495				     ATA_ABORTED)))
2496			ata_dev_err(qc->dev, "error: { %s%s%s%s}\n",
2497			  res->feature & ATA_ICRC ? "ICRC " : "",
2498			  res->feature & ATA_UNC ? "UNC " : "",
 
2499			  res->feature & ATA_IDNF ? "IDNF " : "",
2500			  res->feature & ATA_ABORTED ? "ABRT " : "");
2501#endif
2502	}
2503}
2504
2505/**
2506 *	ata_eh_report - report error handling to user
2507 *	@ap: ATA port to report EH about
2508 *
2509 *	Report EH to user.
2510 *
2511 *	LOCKING:
2512 *	None.
2513 */
2514void ata_eh_report(struct ata_port *ap)
2515{
2516	struct ata_link *link;
2517
2518	ata_for_each_link(link, ap, HOST_FIRST)
2519		ata_eh_link_report(link);
2520}
2521
2522static int ata_do_reset(struct ata_link *link, ata_reset_fn_t reset,
2523			unsigned int *classes, unsigned long deadline,
2524			bool clear_classes)
2525{
2526	struct ata_device *dev;
2527
2528	if (clear_classes)
2529		ata_for_each_dev(dev, link, ALL)
2530			classes[dev->devno] = ATA_DEV_UNKNOWN;
2531
2532	return reset(link, classes, deadline);
2533}
2534
2535static int ata_eh_followup_srst_needed(struct ata_link *link,
2536				       int rc, const unsigned int *classes)
2537{
2538	if ((link->flags & ATA_LFLAG_NO_SRST) || ata_link_offline(link))
2539		return 0;
2540	if (rc == -EAGAIN)
2541		return 1;
2542	if (sata_pmp_supported(link->ap) && ata_is_host_link(link))
2543		return 1;
2544	return 0;
2545}
2546
2547int ata_eh_reset(struct ata_link *link, int classify,
2548		 ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
2549		 ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
2550{
2551	struct ata_port *ap = link->ap;
2552	struct ata_link *slave = ap->slave_link;
2553	struct ata_eh_context *ehc = &link->eh_context;
2554	struct ata_eh_context *sehc = slave ? &slave->eh_context : NULL;
2555	unsigned int *classes = ehc->classes;
2556	unsigned int lflags = link->flags;
2557	int verbose = !(ehc->i.flags & ATA_EHI_QUIET);
2558	int max_tries = 0, try = 0;
2559	struct ata_link *failed_link;
2560	struct ata_device *dev;
2561	unsigned long deadline, now;
2562	ata_reset_fn_t reset;
2563	unsigned long flags;
2564	u32 sstatus;
2565	int nr_unknown, rc;
2566
2567	/*
2568	 * Prepare to reset
2569	 */
2570	while (ata_eh_reset_timeouts[max_tries] != ULONG_MAX)
2571		max_tries++;
 
 
2572	if (link->flags & ATA_LFLAG_NO_HRST)
2573		hardreset = NULL;
2574	if (link->flags & ATA_LFLAG_NO_SRST)
2575		softreset = NULL;
2576
2577	/* make sure each reset attempt is at least COOL_DOWN apart */
2578	if (ehc->i.flags & ATA_EHI_DID_RESET) {
2579		now = jiffies;
2580		WARN_ON(time_after(ehc->last_reset, now));
2581		deadline = ata_deadline(ehc->last_reset,
2582					ATA_EH_RESET_COOL_DOWN);
2583		if (time_before(now, deadline))
2584			schedule_timeout_uninterruptible(deadline - now);
2585	}
2586
2587	spin_lock_irqsave(ap->lock, flags);
2588	ap->pflags |= ATA_PFLAG_RESETTING;
2589	spin_unlock_irqrestore(ap->lock, flags);
2590
2591	ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2592
2593	ata_for_each_dev(dev, link, ALL) {
2594		/* If we issue an SRST then an ATA drive (not ATAPI)
2595		 * may change configuration and be in PIO0 timing. If
2596		 * we do a hard reset (or are coming from power on)
2597		 * this is true for ATA or ATAPI. Until we've set a
2598		 * suitable controller mode we should not touch the
2599		 * bus as we may be talking too fast.
2600		 */
2601		dev->pio_mode = XFER_PIO_0;
 
2602
2603		/* If the controller has a pio mode setup function
2604		 * then use it to set the chipset to rights. Don't
2605		 * touch the DMA setup as that will be dealt with when
2606		 * configuring devices.
2607		 */
2608		if (ap->ops->set_piomode)
2609			ap->ops->set_piomode(ap, dev);
2610	}
2611
2612	/* prefer hardreset */
2613	reset = NULL;
2614	ehc->i.action &= ~ATA_EH_RESET;
2615	if (hardreset) {
2616		reset = hardreset;
2617		ehc->i.action |= ATA_EH_HARDRESET;
2618	} else if (softreset) {
2619		reset = softreset;
2620		ehc->i.action |= ATA_EH_SOFTRESET;
2621	}
2622
2623	if (prereset) {
2624		unsigned long deadline = ata_deadline(jiffies,
2625						      ATA_EH_PRERESET_TIMEOUT);
2626
2627		if (slave) {
2628			sehc->i.action &= ~ATA_EH_RESET;
2629			sehc->i.action |= ehc->i.action;
2630		}
2631
2632		rc = prereset(link, deadline);
2633
2634		/* If present, do prereset on slave link too.  Reset
2635		 * is skipped iff both master and slave links report
2636		 * -ENOENT or clear ATA_EH_RESET.
2637		 */
2638		if (slave && (rc == 0 || rc == -ENOENT)) {
2639			int tmp;
2640
2641			tmp = prereset(slave, deadline);
2642			if (tmp != -ENOENT)
2643				rc = tmp;
2644
2645			ehc->i.action |= sehc->i.action;
2646		}
2647
2648		if (rc) {
2649			if (rc == -ENOENT) {
2650				ata_link_dbg(link, "port disabled--ignoring\n");
2651				ehc->i.action &= ~ATA_EH_RESET;
2652
2653				ata_for_each_dev(dev, link, ALL)
2654					classes[dev->devno] = ATA_DEV_NONE;
2655
2656				rc = 0;
2657			} else
2658				ata_link_err(link,
2659					     "prereset failed (errno=%d)\n",
2660					     rc);
2661			goto out;
2662		}
2663
2664		/* prereset() might have cleared ATA_EH_RESET.  If so,
2665		 * bang classes, thaw and return.
2666		 */
2667		if (reset && !(ehc->i.action & ATA_EH_RESET)) {
2668			ata_for_each_dev(dev, link, ALL)
2669				classes[dev->devno] = ATA_DEV_NONE;
2670			if ((ap->pflags & ATA_PFLAG_FROZEN) &&
2671			    ata_is_host_link(link))
2672				ata_eh_thaw_port(ap);
2673			rc = 0;
2674			goto out;
2675		}
2676	}
2677
2678 retry:
2679	/*
2680	 * Perform reset
2681	 */
2682	if (ata_is_host_link(link))
2683		ata_eh_freeze_port(ap);
2684
2685	deadline = ata_deadline(jiffies, ata_eh_reset_timeouts[try++]);
2686
2687	if (reset) {
2688		if (verbose)
2689			ata_link_info(link, "%s resetting link\n",
2690				      reset == softreset ? "soft" : "hard");
2691
2692		/* mark that this EH session started with reset */
2693		ehc->last_reset = jiffies;
2694		if (reset == hardreset)
2695			ehc->i.flags |= ATA_EHI_DID_HARDRESET;
2696		else
2697			ehc->i.flags |= ATA_EHI_DID_SOFTRESET;
2698
2699		rc = ata_do_reset(link, reset, classes, deadline, true);
2700		if (rc && rc != -EAGAIN) {
2701			failed_link = link;
2702			goto fail;
2703		}
2704
2705		/* hardreset slave link if existent */
2706		if (slave && reset == hardreset) {
2707			int tmp;
2708
2709			if (verbose)
2710				ata_link_info(slave, "hard resetting link\n");
2711
2712			ata_eh_about_to_do(slave, NULL, ATA_EH_RESET);
2713			tmp = ata_do_reset(slave, reset, classes, deadline,
2714					   false);
2715			switch (tmp) {
2716			case -EAGAIN:
2717				rc = -EAGAIN;
2718			case 0:
2719				break;
2720			default:
2721				failed_link = slave;
2722				rc = tmp;
2723				goto fail;
2724			}
2725		}
2726
2727		/* perform follow-up SRST if necessary */
2728		if (reset == hardreset &&
2729		    ata_eh_followup_srst_needed(link, rc, classes)) {
2730			reset = softreset;
2731
2732			if (!reset) {
2733				ata_link_err(link,
2734	     "follow-up softreset required but no softreset available\n");
2735				failed_link = link;
2736				rc = -EINVAL;
2737				goto fail;
2738			}
2739
2740			ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2741			rc = ata_do_reset(link, reset, classes, deadline, true);
2742			if (rc) {
2743				failed_link = link;
2744				goto fail;
2745			}
2746		}
2747	} else {
2748		if (verbose)
2749			ata_link_info(link,
2750	"no reset method available, skipping reset\n");
2751		if (!(lflags & ATA_LFLAG_ASSUME_CLASS))
2752			lflags |= ATA_LFLAG_ASSUME_ATA;
2753	}
2754
2755	/*
2756	 * Post-reset processing
2757	 */
2758	ata_for_each_dev(dev, link, ALL) {
2759		/* After the reset, the device state is PIO 0 and the
2760		 * controller state is undefined.  Reset also wakes up
2761		 * drives from sleeping mode.
2762		 */
2763		dev->pio_mode = XFER_PIO_0;
2764		dev->flags &= ~ATA_DFLAG_SLEEPING;
2765
2766		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
2767			continue;
2768
2769		/* apply class override */
2770		if (lflags & ATA_LFLAG_ASSUME_ATA)
2771			classes[dev->devno] = ATA_DEV_ATA;
2772		else if (lflags & ATA_LFLAG_ASSUME_SEMB)
2773			classes[dev->devno] = ATA_DEV_SEMB_UNSUP;
2774	}
2775
2776	/* record current link speed */
2777	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0)
2778		link->sata_spd = (sstatus >> 4) & 0xf;
2779	if (slave && sata_scr_read(slave, SCR_STATUS, &sstatus) == 0)
2780		slave->sata_spd = (sstatus >> 4) & 0xf;
2781
2782	/* thaw the port */
2783	if (ata_is_host_link(link))
2784		ata_eh_thaw_port(ap);
2785
2786	/* postreset() should clear hardware SError.  Although SError
2787	 * is cleared during link resume, clearing SError here is
2788	 * necessary as some PHYs raise hotplug events after SRST.
2789	 * This introduces race condition where hotplug occurs between
2790	 * reset and here.  This race is mediated by cross checking
2791	 * link onlineness and classification result later.
2792	 */
2793	if (postreset) {
2794		postreset(link, classes);
2795		if (slave)
2796			postreset(slave, classes);
2797	}
2798
2799	/*
2800	 * Some controllers can't be frozen very well and may set spurious
2801	 * error conditions during reset.  Clear accumulated error
2802	 * information and re-thaw the port if frozen.  As reset is the
2803	 * final recovery action and we cross check link onlineness against
2804	 * device classification later, no hotplug event is lost by this.
2805	 */
2806	spin_lock_irqsave(link->ap->lock, flags);
2807	memset(&link->eh_info, 0, sizeof(link->eh_info));
2808	if (slave)
2809		memset(&slave->eh_info, 0, sizeof(link->eh_info));
2810	ap->pflags &= ~ATA_PFLAG_EH_PENDING;
2811	spin_unlock_irqrestore(link->ap->lock, flags);
2812
2813	if (ap->pflags & ATA_PFLAG_FROZEN)
2814		ata_eh_thaw_port(ap);
2815
2816	/*
2817	 * Make sure onlineness and classification result correspond.
2818	 * Hotplug could have happened during reset and some
2819	 * controllers fail to wait while a drive is spinning up after
2820	 * being hotplugged causing misdetection.  By cross checking
2821	 * link on/offlineness and classification result, those
2822	 * conditions can be reliably detected and retried.
2823	 */
2824	nr_unknown = 0;
2825	ata_for_each_dev(dev, link, ALL) {
2826		if (ata_phys_link_online(ata_dev_phys_link(dev))) {
2827			if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2828				ata_dev_dbg(dev, "link online but device misclassified\n");
2829				classes[dev->devno] = ATA_DEV_NONE;
2830				nr_unknown++;
2831			}
2832		} else if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
2833			if (ata_class_enabled(classes[dev->devno]))
2834				ata_dev_dbg(dev,
2835					    "link offline, clearing class %d to NONE\n",
2836					    classes[dev->devno]);
2837			classes[dev->devno] = ATA_DEV_NONE;
2838		} else if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2839			ata_dev_dbg(dev,
2840				    "link status unknown, clearing UNKNOWN to NONE\n");
2841			classes[dev->devno] = ATA_DEV_NONE;
2842		}
2843	}
2844
2845	if (classify && nr_unknown) {
2846		if (try < max_tries) {
2847			ata_link_warn(link,
2848				      "link online but %d devices misclassified, retrying\n",
2849				      nr_unknown);
2850			failed_link = link;
2851			rc = -EAGAIN;
2852			goto fail;
2853		}
2854		ata_link_warn(link,
2855			      "link online but %d devices misclassified, "
2856			      "device detection might fail\n", nr_unknown);
2857	}
2858
2859	/* reset successful, schedule revalidation */
2860	ata_eh_done(link, NULL, ATA_EH_RESET);
2861	if (slave)
2862		ata_eh_done(slave, NULL, ATA_EH_RESET);
2863	ehc->last_reset = jiffies;		/* update to completion time */
2864	ehc->i.action |= ATA_EH_REVALIDATE;
2865	link->lpm_policy = ATA_LPM_UNKNOWN;	/* reset LPM state */
2866
2867	rc = 0;
2868 out:
2869	/* clear hotplug flag */
2870	ehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2871	if (slave)
2872		sehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2873
2874	spin_lock_irqsave(ap->lock, flags);
2875	ap->pflags &= ~ATA_PFLAG_RESETTING;
2876	spin_unlock_irqrestore(ap->lock, flags);
2877
2878	return rc;
2879
2880 fail:
2881	/* if SCR isn't accessible on a fan-out port, PMP needs to be reset */
2882	if (!ata_is_host_link(link) &&
2883	    sata_scr_read(link, SCR_STATUS, &sstatus))
2884		rc = -ERESTART;
2885
2886	if (rc == -ERESTART || try >= max_tries) {
2887		/*
2888		 * Thaw host port even if reset failed, so that the port
2889		 * can be retried on the next phy event.  This risks
2890		 * repeated EH runs but seems to be a better tradeoff than
2891		 * shutting down a port after a botched hotplug attempt.
2892		 */
2893		if (ata_is_host_link(link))
2894			ata_eh_thaw_port(ap);
2895		goto out;
2896	}
2897
2898	now = jiffies;
2899	if (time_before(now, deadline)) {
2900		unsigned long delta = deadline - now;
2901
2902		ata_link_warn(failed_link,
2903			"reset failed (errno=%d), retrying in %u secs\n",
2904			rc, DIV_ROUND_UP(jiffies_to_msecs(delta), 1000));
2905
2906		ata_eh_release(ap);
2907		while (delta)
2908			delta = schedule_timeout_uninterruptible(delta);
2909		ata_eh_acquire(ap);
2910	}
2911
 
 
 
 
 
 
 
 
 
 
2912	if (try == max_tries - 1) {
2913		sata_down_spd_limit(link, 0);
2914		if (slave)
2915			sata_down_spd_limit(slave, 0);
2916	} else if (rc == -EPIPE)
2917		sata_down_spd_limit(failed_link, 0);
2918
2919	if (hardreset)
2920		reset = hardreset;
2921	goto retry;
2922}
2923
2924static inline void ata_eh_pull_park_action(struct ata_port *ap)
2925{
2926	struct ata_link *link;
2927	struct ata_device *dev;
2928	unsigned long flags;
2929
2930	/*
2931	 * This function can be thought of as an extended version of
2932	 * ata_eh_about_to_do() specially crafted to accommodate the
2933	 * requirements of ATA_EH_PARK handling. Since the EH thread
2934	 * does not leave the do {} while () loop in ata_eh_recover as
2935	 * long as the timeout for a park request to *one* device on
2936	 * the port has not expired, and since we still want to pick
2937	 * up park requests to other devices on the same port or
2938	 * timeout updates for the same device, we have to pull
2939	 * ATA_EH_PARK actions from eh_info into eh_context.i
2940	 * ourselves at the beginning of each pass over the loop.
2941	 *
2942	 * Additionally, all write accesses to &ap->park_req_pending
2943	 * through INIT_COMPLETION() (see below) or complete_all()
2944	 * (see ata_scsi_park_store()) are protected by the host lock.
2945	 * As a result we have that park_req_pending.done is zero on
2946	 * exit from this function, i.e. when ATA_EH_PARK actions for
2947	 * *all* devices on port ap have been pulled into the
2948	 * respective eh_context structs. If, and only if,
2949	 * park_req_pending.done is non-zero by the time we reach
2950	 * wait_for_completion_timeout(), another ATA_EH_PARK action
2951	 * has been scheduled for at least one of the devices on port
2952	 * ap and we have to cycle over the do {} while () loop in
2953	 * ata_eh_recover() again.
2954	 */
2955
2956	spin_lock_irqsave(ap->lock, flags);
2957	INIT_COMPLETION(ap->park_req_pending);
2958	ata_for_each_link(link, ap, EDGE) {
2959		ata_for_each_dev(dev, link, ALL) {
2960			struct ata_eh_info *ehi = &link->eh_info;
2961
2962			link->eh_context.i.dev_action[dev->devno] |=
2963				ehi->dev_action[dev->devno] & ATA_EH_PARK;
2964			ata_eh_clear_action(link, dev, ehi, ATA_EH_PARK);
2965		}
2966	}
2967	spin_unlock_irqrestore(ap->lock, flags);
2968}
2969
2970static void ata_eh_park_issue_cmd(struct ata_device *dev, int park)
2971{
2972	struct ata_eh_context *ehc = &dev->link->eh_context;
2973	struct ata_taskfile tf;
2974	unsigned int err_mask;
2975
2976	ata_tf_init(dev, &tf);
2977	if (park) {
2978		ehc->unloaded_mask |= 1 << dev->devno;
2979		tf.command = ATA_CMD_IDLEIMMEDIATE;
2980		tf.feature = 0x44;
2981		tf.lbal = 0x4c;
2982		tf.lbam = 0x4e;
2983		tf.lbah = 0x55;
2984	} else {
2985		ehc->unloaded_mask &= ~(1 << dev->devno);
2986		tf.command = ATA_CMD_CHK_POWER;
2987	}
2988
2989	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
2990	tf.protocol |= ATA_PROT_NODATA;
2991	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
2992	if (park && (err_mask || tf.lbal != 0xc4)) {
2993		ata_dev_err(dev, "head unload failed!\n");
2994		ehc->unloaded_mask &= ~(1 << dev->devno);
2995	}
2996}
2997
2998static int ata_eh_revalidate_and_attach(struct ata_link *link,
2999					struct ata_device **r_failed_dev)
3000{
3001	struct ata_port *ap = link->ap;
3002	struct ata_eh_context *ehc = &link->eh_context;
3003	struct ata_device *dev;
3004	unsigned int new_mask = 0;
3005	unsigned long flags;
3006	int rc = 0;
3007
3008	DPRINTK("ENTER\n");
3009
3010	/* For PATA drive side cable detection to work, IDENTIFY must
3011	 * be done backwards such that PDIAG- is released by the slave
3012	 * device before the master device is identified.
3013	 */
3014	ata_for_each_dev(dev, link, ALL_REVERSE) {
3015		unsigned int action = ata_eh_dev_action(dev);
3016		unsigned int readid_flags = 0;
3017
3018		if (ehc->i.flags & ATA_EHI_DID_RESET)
3019			readid_flags |= ATA_READID_POSTRESET;
3020
3021		if ((action & ATA_EH_REVALIDATE) && ata_dev_enabled(dev)) {
3022			WARN_ON(dev->class == ATA_DEV_PMP);
3023
3024			if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
3025				rc = -EIO;
3026				goto err;
3027			}
3028
3029			ata_eh_about_to_do(link, dev, ATA_EH_REVALIDATE);
3030			rc = ata_dev_revalidate(dev, ehc->classes[dev->devno],
3031						readid_flags);
3032			if (rc)
3033				goto err;
3034
3035			ata_eh_done(link, dev, ATA_EH_REVALIDATE);
3036
3037			/* Configuration may have changed, reconfigure
3038			 * transfer mode.
3039			 */
3040			ehc->i.flags |= ATA_EHI_SETMODE;
3041
3042			/* schedule the scsi_rescan_device() here */
3043			schedule_work(&(ap->scsi_rescan_task));
3044		} else if (dev->class == ATA_DEV_UNKNOWN &&
3045			   ehc->tries[dev->devno] &&
3046			   ata_class_enabled(ehc->classes[dev->devno])) {
3047			/* Temporarily set dev->class, it will be
3048			 * permanently set once all configurations are
3049			 * complete.  This is necessary because new
3050			 * device configuration is done in two
3051			 * separate loops.
3052			 */
3053			dev->class = ehc->classes[dev->devno];
3054
3055			if (dev->class == ATA_DEV_PMP)
3056				rc = sata_pmp_attach(dev);
3057			else
3058				rc = ata_dev_read_id(dev, &dev->class,
3059						     readid_flags, dev->id);
3060
3061			/* read_id might have changed class, store and reset */
3062			ehc->classes[dev->devno] = dev->class;
3063			dev->class = ATA_DEV_UNKNOWN;
3064
3065			switch (rc) {
3066			case 0:
3067				/* clear error info accumulated during probe */
3068				ata_ering_clear(&dev->ering);
3069				new_mask |= 1 << dev->devno;
3070				break;
3071			case -ENOENT:
3072				/* IDENTIFY was issued to non-existent
3073				 * device.  No need to reset.  Just
3074				 * thaw and ignore the device.
3075				 */
3076				ata_eh_thaw_port(ap);
3077				break;
3078			default:
3079				goto err;
3080			}
3081		}
3082	}
3083
3084	/* PDIAG- should have been released, ask cable type if post-reset */
3085	if ((ehc->i.flags & ATA_EHI_DID_RESET) && ata_is_host_link(link)) {
3086		if (ap->ops->cable_detect)
3087			ap->cbl = ap->ops->cable_detect(ap);
3088		ata_force_cbl(ap);
3089	}
3090
3091	/* Configure new devices forward such that user doesn't see
3092	 * device detection messages backwards.
3093	 */
3094	ata_for_each_dev(dev, link, ALL) {
3095		if (!(new_mask & (1 << dev->devno)))
3096			continue;
3097
3098		dev->class = ehc->classes[dev->devno];
3099
3100		if (dev->class == ATA_DEV_PMP)
3101			continue;
3102
3103		ehc->i.flags |= ATA_EHI_PRINTINFO;
3104		rc = ata_dev_configure(dev);
3105		ehc->i.flags &= ~ATA_EHI_PRINTINFO;
3106		if (rc) {
3107			dev->class = ATA_DEV_UNKNOWN;
3108			goto err;
3109		}
3110
3111		spin_lock_irqsave(ap->lock, flags);
3112		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
3113		spin_unlock_irqrestore(ap->lock, flags);
3114
3115		/* new device discovered, configure xfermode */
3116		ehc->i.flags |= ATA_EHI_SETMODE;
3117	}
3118
3119	return 0;
3120
3121 err:
3122	*r_failed_dev = dev;
3123	DPRINTK("EXIT rc=%d\n", rc);
3124	return rc;
3125}
3126
3127/**
3128 *	ata_set_mode - Program timings and issue SET FEATURES - XFER
3129 *	@link: link on which timings will be programmed
3130 *	@r_failed_dev: out parameter for failed device
3131 *
3132 *	Set ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3133 *	ata_set_mode() fails, pointer to the failing device is
3134 *	returned in @r_failed_dev.
3135 *
3136 *	LOCKING:
3137 *	PCI/etc. bus probe sem.
3138 *
3139 *	RETURNS:
3140 *	0 on success, negative errno otherwise
3141 */
3142int ata_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3143{
3144	struct ata_port *ap = link->ap;
3145	struct ata_device *dev;
3146	int rc;
3147
3148	/* if data transfer is verified, clear DUBIOUS_XFER on ering top */
3149	ata_for_each_dev(dev, link, ENABLED) {
3150		if (!(dev->flags & ATA_DFLAG_DUBIOUS_XFER)) {
3151			struct ata_ering_entry *ent;
3152
3153			ent = ata_ering_top(&dev->ering);
3154			if (ent)
3155				ent->eflags &= ~ATA_EFLAG_DUBIOUS_XFER;
3156		}
3157	}
3158
3159	/* has private set_mode? */
3160	if (ap->ops->set_mode)
3161		rc = ap->ops->set_mode(link, r_failed_dev);
3162	else
3163		rc = ata_do_set_mode(link, r_failed_dev);
3164
3165	/* if transfer mode has changed, set DUBIOUS_XFER on device */
3166	ata_for_each_dev(dev, link, ENABLED) {
3167		struct ata_eh_context *ehc = &link->eh_context;
3168		u8 saved_xfer_mode = ehc->saved_xfer_mode[dev->devno];
3169		u8 saved_ncq = !!(ehc->saved_ncq_enabled & (1 << dev->devno));
3170
3171		if (dev->xfer_mode != saved_xfer_mode ||
3172		    ata_ncq_enabled(dev) != saved_ncq)
3173			dev->flags |= ATA_DFLAG_DUBIOUS_XFER;
3174	}
3175
3176	return rc;
3177}
3178
3179/**
3180 *	atapi_eh_clear_ua - Clear ATAPI UNIT ATTENTION after reset
3181 *	@dev: ATAPI device to clear UA for
3182 *
3183 *	Resets and other operations can make an ATAPI device raise
3184 *	UNIT ATTENTION which causes the next operation to fail.  This
3185 *	function clears UA.
3186 *
3187 *	LOCKING:
3188 *	EH context (may sleep).
3189 *
3190 *	RETURNS:
3191 *	0 on success, -errno on failure.
3192 */
3193static int atapi_eh_clear_ua(struct ata_device *dev)
3194{
3195	int i;
3196
3197	for (i = 0; i < ATA_EH_UA_TRIES; i++) {
3198		u8 *sense_buffer = dev->link->ap->sector_buf;
3199		u8 sense_key = 0;
3200		unsigned int err_mask;
3201
3202		err_mask = atapi_eh_tur(dev, &sense_key);
3203		if (err_mask != 0 && err_mask != AC_ERR_DEV) {
3204			ata_dev_warn(dev,
3205				     "TEST_UNIT_READY failed (err_mask=0x%x)\n",
3206				     err_mask);
3207			return -EIO;
3208		}
3209
3210		if (!err_mask || sense_key != UNIT_ATTENTION)
3211			return 0;
3212
3213		err_mask = atapi_eh_request_sense(dev, sense_buffer, sense_key);
3214		if (err_mask) {
3215			ata_dev_warn(dev, "failed to clear "
3216				"UNIT ATTENTION (err_mask=0x%x)\n", err_mask);
3217			return -EIO;
3218		}
3219	}
3220
3221	ata_dev_warn(dev, "UNIT ATTENTION persists after %d tries\n",
3222		     ATA_EH_UA_TRIES);
3223
3224	return 0;
3225}
3226
3227/**
3228 *	ata_eh_maybe_retry_flush - Retry FLUSH if necessary
3229 *	@dev: ATA device which may need FLUSH retry
3230 *
3231 *	If @dev failed FLUSH, it needs to be reported upper layer
3232 *	immediately as it means that @dev failed to remap and already
3233 *	lost at least a sector and further FLUSH retrials won't make
3234 *	any difference to the lost sector.  However, if FLUSH failed
3235 *	for other reasons, for example transmission error, FLUSH needs
3236 *	to be retried.
3237 *
3238 *	This function determines whether FLUSH failure retry is
3239 *	necessary and performs it if so.
3240 *
3241 *	RETURNS:
3242 *	0 if EH can continue, -errno if EH needs to be repeated.
3243 */
3244static int ata_eh_maybe_retry_flush(struct ata_device *dev)
3245{
3246	struct ata_link *link = dev->link;
3247	struct ata_port *ap = link->ap;
3248	struct ata_queued_cmd *qc;
3249	struct ata_taskfile tf;
3250	unsigned int err_mask;
3251	int rc = 0;
3252
3253	/* did flush fail for this device? */
3254	if (!ata_tag_valid(link->active_tag))
3255		return 0;
3256
3257	qc = __ata_qc_from_tag(ap, link->active_tag);
3258	if (qc->dev != dev || (qc->tf.command != ATA_CMD_FLUSH_EXT &&
3259			       qc->tf.command != ATA_CMD_FLUSH))
3260		return 0;
3261
3262	/* if the device failed it, it should be reported to upper layers */
3263	if (qc->err_mask & AC_ERR_DEV)
3264		return 0;
3265
3266	/* flush failed for some other reason, give it another shot */
3267	ata_tf_init(dev, &tf);
3268
3269	tf.command = qc->tf.command;
3270	tf.flags |= ATA_TFLAG_DEVICE;
3271	tf.protocol = ATA_PROT_NODATA;
3272
3273	ata_dev_warn(dev, "retrying FLUSH 0x%x Emask 0x%x\n",
3274		       tf.command, qc->err_mask);
3275
3276	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
3277	if (!err_mask) {
3278		/*
3279		 * FLUSH is complete but there's no way to
3280		 * successfully complete a failed command from EH.
3281		 * Making sure retry is allowed at least once and
3282		 * retrying it should do the trick - whatever was in
3283		 * the cache is already on the platter and this won't
3284		 * cause infinite loop.
3285		 */
3286		qc->scsicmd->allowed = max(qc->scsicmd->allowed, 1);
3287	} else {
3288		ata_dev_warn(dev, "FLUSH failed Emask 0x%x\n",
3289			       err_mask);
3290		rc = -EIO;
3291
3292		/* if device failed it, report it to upper layers */
3293		if (err_mask & AC_ERR_DEV) {
3294			qc->err_mask |= AC_ERR_DEV;
3295			qc->result_tf = tf;
3296			if (!(ap->pflags & ATA_PFLAG_FROZEN))
3297				rc = 0;
3298		}
3299	}
3300	return rc;
3301}
3302
3303/**
3304 *	ata_eh_set_lpm - configure SATA interface power management
3305 *	@link: link to configure power management
3306 *	@policy: the link power management policy
3307 *	@r_failed_dev: out parameter for failed device
3308 *
3309 *	Enable SATA Interface power management.  This will enable
3310 *	Device Interface Power Management (DIPM) for min_power
3311 * 	policy, and then call driver specific callbacks for
3312 *	enabling Host Initiated Power management.
3313 *
3314 *	LOCKING:
3315 *	EH context.
3316 *
3317 *	RETURNS:
3318 *	0 on success, -errno on failure.
3319 */
3320static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
3321			  struct ata_device **r_failed_dev)
3322{
3323	struct ata_port *ap = ata_is_host_link(link) ? link->ap : NULL;
3324	struct ata_eh_context *ehc = &link->eh_context;
3325	struct ata_device *dev, *link_dev = NULL, *lpm_dev = NULL;
3326	enum ata_lpm_policy old_policy = link->lpm_policy;
3327	bool no_dipm = link->ap->flags & ATA_FLAG_NO_DIPM;
3328	unsigned int hints = ATA_LPM_EMPTY | ATA_LPM_HIPM;
3329	unsigned int err_mask;
3330	int rc;
3331
3332	/* if the link or host doesn't do LPM, noop */
3333	if ((link->flags & ATA_LFLAG_NO_LPM) || (ap && !ap->ops->set_lpm))
 
3334		return 0;
3335
3336	/*
3337	 * DIPM is enabled only for MIN_POWER as some devices
3338	 * misbehave when the host NACKs transition to SLUMBER.  Order
3339	 * device and link configurations such that the host always
3340	 * allows DIPM requests.
3341	 */
3342	ata_for_each_dev(dev, link, ENABLED) {
3343		bool hipm = ata_id_has_hipm(dev->id);
3344		bool dipm = ata_id_has_dipm(dev->id) && !no_dipm;
3345
3346		/* find the first enabled and LPM enabled devices */
3347		if (!link_dev)
3348			link_dev = dev;
3349
3350		if (!lpm_dev && (hipm || dipm))
3351			lpm_dev = dev;
3352
3353		hints &= ~ATA_LPM_EMPTY;
3354		if (!hipm)
3355			hints &= ~ATA_LPM_HIPM;
3356
3357		/* disable DIPM before changing link config */
3358		if (policy != ATA_LPM_MIN_POWER && dipm) {
3359			err_mask = ata_dev_set_feature(dev,
3360					SETFEATURES_SATA_DISABLE, SATA_DIPM);
3361			if (err_mask && err_mask != AC_ERR_DEV) {
3362				ata_dev_warn(dev,
3363					     "failed to disable DIPM, Emask 0x%x\n",
3364					     err_mask);
3365				rc = -EIO;
3366				goto fail;
3367			}
3368		}
3369	}
3370
3371	if (ap) {
3372		rc = ap->ops->set_lpm(link, policy, hints);
3373		if (!rc && ap->slave_link)
3374			rc = ap->ops->set_lpm(ap->slave_link, policy, hints);
3375	} else
3376		rc = sata_pmp_set_lpm(link, policy, hints);
3377
3378	/*
3379	 * Attribute link config failure to the first (LPM) enabled
3380	 * device on the link.
3381	 */
3382	if (rc) {
3383		if (rc == -EOPNOTSUPP) {
3384			link->flags |= ATA_LFLAG_NO_LPM;
3385			return 0;
3386		}
3387		dev = lpm_dev ? lpm_dev : link_dev;
3388		goto fail;
3389	}
3390
3391	/*
3392	 * Low level driver acked the transition.  Issue DIPM command
3393	 * with the new policy set.
3394	 */
3395	link->lpm_policy = policy;
3396	if (ap && ap->slave_link)
3397		ap->slave_link->lpm_policy = policy;
3398
3399	/* host config updated, enable DIPM if transitioning to MIN_POWER */
3400	ata_for_each_dev(dev, link, ENABLED) {
3401		if (policy == ATA_LPM_MIN_POWER && !no_dipm &&
3402		    ata_id_has_dipm(dev->id)) {
3403			err_mask = ata_dev_set_feature(dev,
3404					SETFEATURES_SATA_ENABLE, SATA_DIPM);
3405			if (err_mask && err_mask != AC_ERR_DEV) {
3406				ata_dev_warn(dev,
3407					"failed to enable DIPM, Emask 0x%x\n",
3408					err_mask);
3409				rc = -EIO;
3410				goto fail;
3411			}
3412		}
3413	}
3414
 
 
 
3415	return 0;
3416
3417fail:
3418	/* restore the old policy */
3419	link->lpm_policy = old_policy;
3420	if (ap && ap->slave_link)
3421		ap->slave_link->lpm_policy = old_policy;
3422
3423	/* if no device or only one more chance is left, disable LPM */
3424	if (!dev || ehc->tries[dev->devno] <= 2) {
3425		ata_link_warn(link, "disabling LPM on the link\n");
3426		link->flags |= ATA_LFLAG_NO_LPM;
3427	}
3428	if (r_failed_dev)
3429		*r_failed_dev = dev;
3430	return rc;
3431}
3432
3433int ata_link_nr_enabled(struct ata_link *link)
3434{
3435	struct ata_device *dev;
3436	int cnt = 0;
3437
3438	ata_for_each_dev(dev, link, ENABLED)
3439		cnt++;
3440	return cnt;
3441}
3442
3443static int ata_link_nr_vacant(struct ata_link *link)
3444{
3445	struct ata_device *dev;
3446	int cnt = 0;
3447
3448	ata_for_each_dev(dev, link, ALL)
3449		if (dev->class == ATA_DEV_UNKNOWN)
3450			cnt++;
3451	return cnt;
3452}
3453
3454static int ata_eh_skip_recovery(struct ata_link *link)
3455{
3456	struct ata_port *ap = link->ap;
3457	struct ata_eh_context *ehc = &link->eh_context;
3458	struct ata_device *dev;
3459
3460	/* skip disabled links */
3461	if (link->flags & ATA_LFLAG_DISABLED)
3462		return 1;
3463
3464	/* skip if explicitly requested */
3465	if (ehc->i.flags & ATA_EHI_NO_RECOVERY)
3466		return 1;
3467
3468	/* thaw frozen port and recover failed devices */
3469	if ((ap->pflags & ATA_PFLAG_FROZEN) || ata_link_nr_enabled(link))
3470		return 0;
3471
3472	/* reset at least once if reset is requested */
3473	if ((ehc->i.action & ATA_EH_RESET) &&
3474	    !(ehc->i.flags & ATA_EHI_DID_RESET))
3475		return 0;
3476
3477	/* skip if class codes for all vacant slots are ATA_DEV_NONE */
3478	ata_for_each_dev(dev, link, ALL) {
3479		if (dev->class == ATA_DEV_UNKNOWN &&
3480		    ehc->classes[dev->devno] != ATA_DEV_NONE)
3481			return 0;
3482	}
3483
3484	return 1;
3485}
3486
3487static int ata_count_probe_trials_cb(struct ata_ering_entry *ent, void *void_arg)
3488{
3489	u64 interval = msecs_to_jiffies(ATA_EH_PROBE_TRIAL_INTERVAL);
3490	u64 now = get_jiffies_64();
3491	int *trials = void_arg;
3492
3493	if (ent->timestamp < now - min(now, interval))
 
3494		return -1;
3495
3496	(*trials)++;
3497	return 0;
3498}
3499
3500static int ata_eh_schedule_probe(struct ata_device *dev)
3501{
3502	struct ata_eh_context *ehc = &dev->link->eh_context;
3503	struct ata_link *link = ata_dev_phys_link(dev);
3504	int trials = 0;
3505
3506	if (!(ehc->i.probe_mask & (1 << dev->devno)) ||
3507	    (ehc->did_probe_mask & (1 << dev->devno)))
3508		return 0;
3509
3510	ata_eh_detach_dev(dev);
3511	ata_dev_init(dev);
3512	ehc->did_probe_mask |= (1 << dev->devno);
3513	ehc->i.action |= ATA_EH_RESET;
3514	ehc->saved_xfer_mode[dev->devno] = 0;
3515	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
3516
3517	/* the link maybe in a deep sleep, wake it up */
3518	if (link->lpm_policy > ATA_LPM_MAX_POWER) {
3519		if (ata_is_host_link(link))
3520			link->ap->ops->set_lpm(link, ATA_LPM_MAX_POWER,
3521					       ATA_LPM_EMPTY);
3522		else
3523			sata_pmp_set_lpm(link, ATA_LPM_MAX_POWER,
3524					 ATA_LPM_EMPTY);
3525	}
3526
3527	/* Record and count probe trials on the ering.  The specific
3528	 * error mask used is irrelevant.  Because a successful device
3529	 * detection clears the ering, this count accumulates only if
3530	 * there are consecutive failed probes.
3531	 *
3532	 * If the count is equal to or higher than ATA_EH_PROBE_TRIALS
3533	 * in the last ATA_EH_PROBE_TRIAL_INTERVAL, link speed is
3534	 * forced to 1.5Gbps.
3535	 *
3536	 * This is to work around cases where failed link speed
3537	 * negotiation results in device misdetection leading to
3538	 * infinite DEVXCHG or PHRDY CHG events.
3539	 */
3540	ata_ering_record(&dev->ering, 0, AC_ERR_OTHER);
3541	ata_ering_map(&dev->ering, ata_count_probe_trials_cb, &trials);
3542
3543	if (trials > ATA_EH_PROBE_TRIALS)
3544		sata_down_spd_limit(link, 1);
3545
3546	return 1;
3547}
3548
3549static int ata_eh_handle_dev_fail(struct ata_device *dev, int err)
3550{
3551	struct ata_eh_context *ehc = &dev->link->eh_context;
3552
3553	/* -EAGAIN from EH routine indicates retry without prejudice.
3554	 * The requester is responsible for ensuring forward progress.
3555	 */
3556	if (err != -EAGAIN)
3557		ehc->tries[dev->devno]--;
3558
3559	switch (err) {
3560	case -ENODEV:
3561		/* device missing or wrong IDENTIFY data, schedule probing */
3562		ehc->i.probe_mask |= (1 << dev->devno);
 
3563	case -EINVAL:
3564		/* give it just one more chance */
3565		ehc->tries[dev->devno] = min(ehc->tries[dev->devno], 1);
 
3566	case -EIO:
3567		if (ehc->tries[dev->devno] == 1) {
3568			/* This is the last chance, better to slow
3569			 * down than lose it.
3570			 */
3571			sata_down_spd_limit(ata_dev_phys_link(dev), 0);
3572			if (dev->pio_mode > XFER_PIO_0)
3573				ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
3574		}
3575	}
3576
3577	if (ata_dev_enabled(dev) && !ehc->tries[dev->devno]) {
3578		/* disable device if it has used up all its chances */
3579		ata_dev_disable(dev);
3580
3581		/* detach if offline */
3582		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
3583			ata_eh_detach_dev(dev);
3584
3585		/* schedule probe if necessary */
3586		if (ata_eh_schedule_probe(dev)) {
3587			ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3588			memset(ehc->cmd_timeout_idx[dev->devno], 0,
3589			       sizeof(ehc->cmd_timeout_idx[dev->devno]));
3590		}
3591
3592		return 1;
3593	} else {
3594		ehc->i.action |= ATA_EH_RESET;
3595		return 0;
3596	}
3597}
3598
3599/**
3600 *	ata_eh_recover - recover host port after error
3601 *	@ap: host port to recover
3602 *	@prereset: prereset method (can be NULL)
3603 *	@softreset: softreset method (can be NULL)
3604 *	@hardreset: hardreset method (can be NULL)
3605 *	@postreset: postreset method (can be NULL)
3606 *	@r_failed_link: out parameter for failed link
3607 *
3608 *	This is the alpha and omega, eum and yang, heart and soul of
3609 *	libata exception handling.  On entry, actions required to
3610 *	recover each link and hotplug requests are recorded in the
3611 *	link's eh_context.  This function executes all the operations
3612 *	with appropriate retrials and fallbacks to resurrect failed
3613 *	devices, detach goners and greet newcomers.
3614 *
3615 *	LOCKING:
3616 *	Kernel thread context (may sleep).
3617 *
3618 *	RETURNS:
3619 *	0 on success, -errno on failure.
3620 */
3621int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
3622		   ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3623		   ata_postreset_fn_t postreset,
3624		   struct ata_link **r_failed_link)
3625{
3626	struct ata_link *link;
3627	struct ata_device *dev;
3628	int rc, nr_fails;
3629	unsigned long flags, deadline;
3630
3631	DPRINTK("ENTER\n");
3632
3633	/* prep for recovery */
3634	ata_for_each_link(link, ap, EDGE) {
3635		struct ata_eh_context *ehc = &link->eh_context;
3636
3637		/* re-enable link? */
3638		if (ehc->i.action & ATA_EH_ENABLE_LINK) {
3639			ata_eh_about_to_do(link, NULL, ATA_EH_ENABLE_LINK);
3640			spin_lock_irqsave(ap->lock, flags);
3641			link->flags &= ~ATA_LFLAG_DISABLED;
3642			spin_unlock_irqrestore(ap->lock, flags);
3643			ata_eh_done(link, NULL, ATA_EH_ENABLE_LINK);
3644		}
3645
3646		ata_for_each_dev(dev, link, ALL) {
3647			if (link->flags & ATA_LFLAG_NO_RETRY)
3648				ehc->tries[dev->devno] = 1;
3649			else
3650				ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3651
3652			/* collect port action mask recorded in dev actions */
3653			ehc->i.action |= ehc->i.dev_action[dev->devno] &
3654					 ~ATA_EH_PERDEV_MASK;
3655			ehc->i.dev_action[dev->devno] &= ATA_EH_PERDEV_MASK;
3656
3657			/* process hotplug request */
3658			if (dev->flags & ATA_DFLAG_DETACH)
3659				ata_eh_detach_dev(dev);
3660
3661			/* schedule probe if necessary */
3662			if (!ata_dev_enabled(dev))
3663				ata_eh_schedule_probe(dev);
3664		}
3665	}
3666
3667 retry:
3668	rc = 0;
3669
3670	/* if UNLOADING, finish immediately */
3671	if (ap->pflags & ATA_PFLAG_UNLOADING)
3672		goto out;
3673
3674	/* prep for EH */
3675	ata_for_each_link(link, ap, EDGE) {
3676		struct ata_eh_context *ehc = &link->eh_context;
3677
3678		/* skip EH if possible. */
3679		if (ata_eh_skip_recovery(link))
3680			ehc->i.action = 0;
3681
3682		ata_for_each_dev(dev, link, ALL)
3683			ehc->classes[dev->devno] = ATA_DEV_UNKNOWN;
3684	}
3685
3686	/* reset */
3687	ata_for_each_link(link, ap, EDGE) {
3688		struct ata_eh_context *ehc = &link->eh_context;
3689
3690		if (!(ehc->i.action & ATA_EH_RESET))
3691			continue;
3692
3693		rc = ata_eh_reset(link, ata_link_nr_vacant(link),
3694				  prereset, softreset, hardreset, postreset);
3695		if (rc) {
3696			ata_link_err(link, "reset failed, giving up\n");
3697			goto out;
3698		}
3699	}
3700
3701	do {
3702		unsigned long now;
3703
3704		/*
3705		 * clears ATA_EH_PARK in eh_info and resets
3706		 * ap->park_req_pending
3707		 */
3708		ata_eh_pull_park_action(ap);
3709
3710		deadline = jiffies;
3711		ata_for_each_link(link, ap, EDGE) {
3712			ata_for_each_dev(dev, link, ALL) {
3713				struct ata_eh_context *ehc = &link->eh_context;
3714				unsigned long tmp;
3715
3716				if (dev->class != ATA_DEV_ATA)
 
3717					continue;
3718				if (!(ehc->i.dev_action[dev->devno] &
3719				      ATA_EH_PARK))
3720					continue;
3721				tmp = dev->unpark_deadline;
3722				if (time_before(deadline, tmp))
3723					deadline = tmp;
3724				else if (time_before_eq(tmp, jiffies))
3725					continue;
3726				if (ehc->unloaded_mask & (1 << dev->devno))
3727					continue;
3728
3729				ata_eh_park_issue_cmd(dev, 1);
3730			}
3731		}
3732
3733		now = jiffies;
3734		if (time_before_eq(deadline, now))
3735			break;
3736
3737		ata_eh_release(ap);
3738		deadline = wait_for_completion_timeout(&ap->park_req_pending,
3739						       deadline - now);
3740		ata_eh_acquire(ap);
3741	} while (deadline);
3742	ata_for_each_link(link, ap, EDGE) {
3743		ata_for_each_dev(dev, link, ALL) {
3744			if (!(link->eh_context.unloaded_mask &
3745			      (1 << dev->devno)))
3746				continue;
3747
3748			ata_eh_park_issue_cmd(dev, 0);
3749			ata_eh_done(link, dev, ATA_EH_PARK);
3750		}
3751	}
3752
3753	/* the rest */
3754	nr_fails = 0;
3755	ata_for_each_link(link, ap, PMP_FIRST) {
3756		struct ata_eh_context *ehc = &link->eh_context;
3757
3758		if (sata_pmp_attached(ap) && ata_is_host_link(link))
3759			goto config_lpm;
3760
3761		/* revalidate existing devices and attach new ones */
3762		rc = ata_eh_revalidate_and_attach(link, &dev);
3763		if (rc)
3764			goto rest_fail;
3765
3766		/* if PMP got attached, return, pmp EH will take care of it */
3767		if (link->device->class == ATA_DEV_PMP) {
3768			ehc->i.action = 0;
3769			return 0;
3770		}
3771
3772		/* configure transfer mode if necessary */
3773		if (ehc->i.flags & ATA_EHI_SETMODE) {
3774			rc = ata_set_mode(link, &dev);
3775			if (rc)
3776				goto rest_fail;
3777			ehc->i.flags &= ~ATA_EHI_SETMODE;
3778		}
3779
3780		/* If reset has been issued, clear UA to avoid
3781		 * disrupting the current users of the device.
3782		 */
3783		if (ehc->i.flags & ATA_EHI_DID_RESET) {
3784			ata_for_each_dev(dev, link, ALL) {
3785				if (dev->class != ATA_DEV_ATAPI)
3786					continue;
3787				rc = atapi_eh_clear_ua(dev);
3788				if (rc)
3789					goto rest_fail;
 
 
3790			}
3791		}
3792
3793		/* retry flush if necessary */
3794		ata_for_each_dev(dev, link, ALL) {
3795			if (dev->class != ATA_DEV_ATA)
 
3796				continue;
3797			rc = ata_eh_maybe_retry_flush(dev);
3798			if (rc)
3799				goto rest_fail;
3800		}
3801
3802	config_lpm:
3803		/* configure link power saving */
3804		if (link->lpm_policy != ap->target_lpm_policy) {
3805			rc = ata_eh_set_lpm(link, ap->target_lpm_policy, &dev);
3806			if (rc)
3807				goto rest_fail;
3808		}
3809
3810		/* this link is okay now */
3811		ehc->i.flags = 0;
3812		continue;
3813
3814	rest_fail:
3815		nr_fails++;
3816		if (dev)
3817			ata_eh_handle_dev_fail(dev, rc);
3818
3819		if (ap->pflags & ATA_PFLAG_FROZEN) {
3820			/* PMP reset requires working host port.
3821			 * Can't retry if it's frozen.
3822			 */
3823			if (sata_pmp_attached(ap))
3824				goto out;
3825			break;
3826		}
3827	}
3828
3829	if (nr_fails)
3830		goto retry;
3831
3832 out:
3833	if (rc && r_failed_link)
3834		*r_failed_link = link;
3835
3836	DPRINTK("EXIT, rc=%d\n", rc);
3837	return rc;
3838}
3839
3840/**
3841 *	ata_eh_finish - finish up EH
3842 *	@ap: host port to finish EH for
3843 *
3844 *	Recovery is complete.  Clean up EH states and retry or finish
3845 *	failed qcs.
3846 *
3847 *	LOCKING:
3848 *	None.
3849 */
3850void ata_eh_finish(struct ata_port *ap)
3851{
 
3852	int tag;
3853
3854	/* retry or finish qcs */
3855	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
3856		struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
3857
3858		if (!(qc->flags & ATA_QCFLAG_FAILED))
3859			continue;
3860
3861		if (qc->err_mask) {
3862			/* FIXME: Once EH migration is complete,
3863			 * generate sense data in this function,
3864			 * considering both err_mask and tf.
3865			 */
3866			if (qc->flags & ATA_QCFLAG_RETRY)
3867				ata_eh_qc_retry(qc);
3868			else
3869				ata_eh_qc_complete(qc);
3870		} else {
3871			if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
3872				ata_eh_qc_complete(qc);
3873			} else {
3874				/* feed zero TF to sense generation */
3875				memset(&qc->result_tf, 0, sizeof(qc->result_tf));
3876				ata_eh_qc_retry(qc);
3877			}
3878		}
3879	}
3880
3881	/* make sure nr_active_links is zero after EH */
3882	WARN_ON(ap->nr_active_links);
3883	ap->nr_active_links = 0;
3884}
3885
3886/**
3887 *	ata_do_eh - do standard error handling
3888 *	@ap: host port to handle error for
3889 *
3890 *	@prereset: prereset method (can be NULL)
3891 *	@softreset: softreset method (can be NULL)
3892 *	@hardreset: hardreset method (can be NULL)
3893 *	@postreset: postreset method (can be NULL)
3894 *
3895 *	Perform standard error handling sequence.
3896 *
3897 *	LOCKING:
3898 *	Kernel thread context (may sleep).
3899 */
3900void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
3901	       ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3902	       ata_postreset_fn_t postreset)
3903{
3904	struct ata_device *dev;
3905	int rc;
3906
3907	ata_eh_autopsy(ap);
3908	ata_eh_report(ap);
3909
3910	rc = ata_eh_recover(ap, prereset, softreset, hardreset, postreset,
3911			    NULL);
3912	if (rc) {
3913		ata_for_each_dev(dev, &ap->link, ALL)
3914			ata_dev_disable(dev);
3915	}
3916
3917	ata_eh_finish(ap);
3918}
3919
3920/**
3921 *	ata_std_error_handler - standard error handler
3922 *	@ap: host port to handle error for
3923 *
3924 *	Standard error handler
3925 *
3926 *	LOCKING:
3927 *	Kernel thread context (may sleep).
3928 */
3929void ata_std_error_handler(struct ata_port *ap)
3930{
3931	struct ata_port_operations *ops = ap->ops;
3932	ata_reset_fn_t hardreset = ops->hardreset;
3933
3934	/* ignore built-in hardreset if SCR access is not available */
3935	if (hardreset == sata_std_hardreset && !sata_scr_valid(&ap->link))
3936		hardreset = NULL;
3937
3938	ata_do_eh(ap, ops->prereset, ops->softreset, hardreset, ops->postreset);
3939}
 
3940
3941#ifdef CONFIG_PM
3942/**
3943 *	ata_eh_handle_port_suspend - perform port suspend operation
3944 *	@ap: port to suspend
3945 *
3946 *	Suspend @ap.
3947 *
3948 *	LOCKING:
3949 *	Kernel thread context (may sleep).
3950 */
3951static void ata_eh_handle_port_suspend(struct ata_port *ap)
3952{
3953	unsigned long flags;
3954	int rc = 0;
 
3955
3956	/* are we suspending? */
3957	spin_lock_irqsave(ap->lock, flags);
3958	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
3959	    ap->pm_mesg.event == PM_EVENT_ON) {
3960		spin_unlock_irqrestore(ap->lock, flags);
3961		return;
3962	}
3963	spin_unlock_irqrestore(ap->lock, flags);
3964
3965	WARN_ON(ap->pflags & ATA_PFLAG_SUSPENDED);
3966
 
 
 
 
 
 
 
 
 
 
 
 
3967	/* tell ACPI we're suspending */
3968	rc = ata_acpi_on_suspend(ap);
3969	if (rc)
3970		goto out;
3971
3972	/* suspend */
3973	ata_eh_freeze_port(ap);
3974
3975	if (ap->ops->port_suspend)
3976		rc = ap->ops->port_suspend(ap, ap->pm_mesg);
3977
3978	ata_acpi_set_state(ap, PMSG_SUSPEND);
3979 out:
3980	/* report result */
3981	spin_lock_irqsave(ap->lock, flags);
3982
3983	ap->pflags &= ~ATA_PFLAG_PM_PENDING;
3984	if (rc == 0)
3985		ap->pflags |= ATA_PFLAG_SUSPENDED;
3986	else if (ap->pflags & ATA_PFLAG_FROZEN)
3987		ata_port_schedule_eh(ap);
3988
3989	if (ap->pm_result) {
3990		*ap->pm_result = rc;
3991		ap->pm_result = NULL;
3992	}
3993
3994	spin_unlock_irqrestore(ap->lock, flags);
3995
3996	return;
3997}
3998
3999/**
4000 *	ata_eh_handle_port_resume - perform port resume operation
4001 *	@ap: port to resume
4002 *
4003 *	Resume @ap.
4004 *
4005 *	LOCKING:
4006 *	Kernel thread context (may sleep).
4007 */
4008static void ata_eh_handle_port_resume(struct ata_port *ap)
4009{
4010	struct ata_link *link;
4011	struct ata_device *dev;
4012	unsigned long flags;
4013	int rc = 0;
4014
4015	/* are we resuming? */
4016	spin_lock_irqsave(ap->lock, flags);
4017	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
4018	    ap->pm_mesg.event != PM_EVENT_ON) {
4019		spin_unlock_irqrestore(ap->lock, flags);
4020		return;
4021	}
4022	spin_unlock_irqrestore(ap->lock, flags);
4023
4024	WARN_ON(!(ap->pflags & ATA_PFLAG_SUSPENDED));
4025
4026	/*
4027	 * Error timestamps are in jiffies which doesn't run while
4028	 * suspended and PHY events during resume isn't too uncommon.
4029	 * When the two are combined, it can lead to unnecessary speed
4030	 * downs if the machine is suspended and resumed repeatedly.
4031	 * Clear error history.
4032	 */
4033	ata_for_each_link(link, ap, HOST_FIRST)
4034		ata_for_each_dev(dev, link, ALL)
4035			ata_ering_clear(&dev->ering);
4036
4037	ata_acpi_set_state(ap, PMSG_ON);
4038
4039	if (ap->ops->port_resume)
4040		rc = ap->ops->port_resume(ap);
4041
4042	/* tell ACPI that we're resuming */
4043	ata_acpi_on_resume(ap);
4044
4045	/* report result */
4046	spin_lock_irqsave(ap->lock, flags);
4047	ap->pflags &= ~(ATA_PFLAG_PM_PENDING | ATA_PFLAG_SUSPENDED);
4048	if (ap->pm_result) {
4049		*ap->pm_result = rc;
4050		ap->pm_result = NULL;
4051	}
4052	spin_unlock_irqrestore(ap->lock, flags);
4053}
4054#endif /* CONFIG_PM */