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