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v4.6
 
   1/*
   2 *  libata-eh.c - libata error handling
   3 *
   4 *  Maintained by:  Tejun Heo <tj@kernel.org>
   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/export.h>
  38#include <linux/pci.h>
  39#include <scsi/scsi.h>
  40#include <scsi/scsi_host.h>
  41#include <scsi/scsi_eh.h>
  42#include <scsi/scsi_device.h>
  43#include <scsi/scsi_cmnd.h>
  44#include <scsi/scsi_dbg.h>
  45#include "../scsi/scsi_transport_api.h"
  46
  47#include <linux/libata.h>
  48
  49#include <trace/events/libata.h>
  50#include "libata.h"
  51
  52enum {
  53	/* speed down verdicts */
  54	ATA_EH_SPDN_NCQ_OFF		= (1 << 0),
  55	ATA_EH_SPDN_SPEED_DOWN		= (1 << 1),
  56	ATA_EH_SPDN_FALLBACK_TO_PIO	= (1 << 2),
  57	ATA_EH_SPDN_KEEP_ERRORS		= (1 << 3),
  58
  59	/* error flags */
  60	ATA_EFLAG_IS_IO			= (1 << 0),
  61	ATA_EFLAG_DUBIOUS_XFER		= (1 << 1),
  62	ATA_EFLAG_OLD_ER                = (1 << 31),
  63
  64	/* error categories */
  65	ATA_ECAT_NONE			= 0,
  66	ATA_ECAT_ATA_BUS		= 1,
  67	ATA_ECAT_TOUT_HSM		= 2,
  68	ATA_ECAT_UNK_DEV		= 3,
  69	ATA_ECAT_DUBIOUS_NONE		= 4,
  70	ATA_ECAT_DUBIOUS_ATA_BUS	= 5,
  71	ATA_ECAT_DUBIOUS_TOUT_HSM	= 6,
  72	ATA_ECAT_DUBIOUS_UNK_DEV	= 7,
  73	ATA_ECAT_NR			= 8,
  74
  75	ATA_EH_CMD_DFL_TIMEOUT		=  5000,
  76
  77	/* always put at least this amount of time between resets */
  78	ATA_EH_RESET_COOL_DOWN		=  5000,
  79
  80	/* Waiting in ->prereset can never be reliable.  It's
  81	 * sometimes nice to wait there but it can't be depended upon;
  82	 * otherwise, we wouldn't be resetting.  Just give it enough
  83	 * time for most drives to spin up.
  84	 */
  85	ATA_EH_PRERESET_TIMEOUT		= 10000,
  86	ATA_EH_FASTDRAIN_INTERVAL	=  3000,
  87
  88	ATA_EH_UA_TRIES			= 5,
  89
  90	/* probe speed down parameters, see ata_eh_schedule_probe() */
  91	ATA_EH_PROBE_TRIAL_INTERVAL	= 60000,	/* 1 min */
  92	ATA_EH_PROBE_TRIALS		= 2,
  93};
  94
  95/* The following table determines how we sequence resets.  Each entry
  96 * represents timeout for that try.  The first try can be soft or
  97 * hardreset.  All others are hardreset if available.  In most cases
  98 * the first reset w/ 10sec timeout should succeed.  Following entries
  99 * are mostly for error handling, hotplug and those outlier devices that
 100 * take an exceptionally long time to recover from reset.
 101 */
 102static const unsigned long ata_eh_reset_timeouts[] = {
 103	10000,	/* most drives spin up by 10sec */
 104	10000,	/* > 99% working drives spin up before 20sec */
 105	35000,	/* give > 30 secs of idleness for outlier devices */
 106	 5000,	/* and sweet one last chance */
 107	ULONG_MAX, /* > 1 min has elapsed, give up */
 108};
 109
 110static const unsigned long ata_eh_identify_timeouts[] = {
 111	 5000,	/* covers > 99% of successes and not too boring on failures */
 112	10000,  /* combined time till here is enough even for media access */
 113	30000,	/* for true idiots */
 114	ULONG_MAX,
 
 
 
 
 
 
 115};
 116
 117static const unsigned long ata_eh_flush_timeouts[] = {
 118	15000,	/* be generous with flush */
 119	15000,  /* ditto */
 120	30000,	/* and even more generous */
 121	ULONG_MAX,
 122};
 123
 124static const unsigned long ata_eh_other_timeouts[] = {
 125	 5000,	/* same rationale as identify timeout */
 126	10000,	/* ditto */
 127	/* but no merciful 30sec for other commands, it just isn't worth it */
 128	ULONG_MAX,
 129};
 130
 131struct ata_eh_cmd_timeout_ent {
 132	const u8		*commands;
 133	const unsigned long	*timeouts;
 134};
 135
 136/* The following table determines timeouts to use for EH internal
 137 * commands.  Each table entry is a command class and matches the
 138 * commands the entry applies to and the timeout table to use.
 139 *
 140 * On the retry after a command timed out, the next timeout value from
 141 * the table is used.  If the table doesn't contain further entries,
 142 * the last value is used.
 143 *
 144 * ehc->cmd_timeout_idx keeps track of which timeout to use per
 145 * command class, so if SET_FEATURES times out on the first try, the
 146 * next try will use the second timeout value only for that class.
 147 */
 148#define CMDS(cmds...)	(const u8 []){ cmds, 0 }
 149static const struct ata_eh_cmd_timeout_ent
 150ata_eh_cmd_timeout_table[ATA_EH_CMD_TIMEOUT_TABLE_SIZE] = {
 151	{ .commands = CMDS(ATA_CMD_ID_ATA, ATA_CMD_ID_ATAPI),
 152	  .timeouts = ata_eh_identify_timeouts, },
 
 
 153	{ .commands = CMDS(ATA_CMD_READ_NATIVE_MAX, ATA_CMD_READ_NATIVE_MAX_EXT),
 154	  .timeouts = ata_eh_other_timeouts, },
 155	{ .commands = CMDS(ATA_CMD_SET_MAX, ATA_CMD_SET_MAX_EXT),
 156	  .timeouts = ata_eh_other_timeouts, },
 157	{ .commands = CMDS(ATA_CMD_SET_FEATURES),
 158	  .timeouts = ata_eh_other_timeouts, },
 159	{ .commands = CMDS(ATA_CMD_INIT_DEV_PARAMS),
 160	  .timeouts = ata_eh_other_timeouts, },
 161	{ .commands = CMDS(ATA_CMD_FLUSH, ATA_CMD_FLUSH_EXT),
 162	  .timeouts = ata_eh_flush_timeouts },
 
 
 163};
 164#undef CMDS
 165
 166static void __ata_port_freeze(struct ata_port *ap);
 
 
 167#ifdef CONFIG_PM
 168static void ata_eh_handle_port_suspend(struct ata_port *ap);
 169static void ata_eh_handle_port_resume(struct ata_port *ap);
 170#else /* CONFIG_PM */
 171static void ata_eh_handle_port_suspend(struct ata_port *ap)
 172{ }
 173
 174static void ata_eh_handle_port_resume(struct ata_port *ap)
 175{ }
 176#endif /* CONFIG_PM */
 177
 178static void __ata_ehi_pushv_desc(struct ata_eh_info *ehi, const char *fmt,
 179				 va_list args)
 180{
 181	ehi->desc_len += vscnprintf(ehi->desc + ehi->desc_len,
 182				     ATA_EH_DESC_LEN - ehi->desc_len,
 183				     fmt, args);
 184}
 185
 186/**
 187 *	__ata_ehi_push_desc - push error description without adding separator
 188 *	@ehi: target EHI
 189 *	@fmt: printf format string
 190 *
 191 *	Format string according to @fmt and append it to @ehi->desc.
 192 *
 193 *	LOCKING:
 194 *	spin_lock_irqsave(host lock)
 195 */
 196void __ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 197{
 198	va_list args;
 199
 200	va_start(args, fmt);
 201	__ata_ehi_pushv_desc(ehi, fmt, args);
 202	va_end(args);
 203}
 
 204
 205/**
 206 *	ata_ehi_push_desc - push error description with separator
 207 *	@ehi: target EHI
 208 *	@fmt: printf format string
 209 *
 210 *	Format string according to @fmt and append it to @ehi->desc.
 211 *	If @ehi->desc is not empty, ", " is added in-between.
 212 *
 213 *	LOCKING:
 214 *	spin_lock_irqsave(host lock)
 215 */
 216void ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
 217{
 218	va_list args;
 219
 220	if (ehi->desc_len)
 221		__ata_ehi_push_desc(ehi, ", ");
 222
 223	va_start(args, fmt);
 224	__ata_ehi_pushv_desc(ehi, fmt, args);
 225	va_end(args);
 226}
 
 227
 228/**
 229 *	ata_ehi_clear_desc - clean error description
 230 *	@ehi: target EHI
 231 *
 232 *	Clear @ehi->desc.
 233 *
 234 *	LOCKING:
 235 *	spin_lock_irqsave(host lock)
 236 */
 237void ata_ehi_clear_desc(struct ata_eh_info *ehi)
 238{
 239	ehi->desc[0] = '\0';
 240	ehi->desc_len = 0;
 241}
 
 242
 243/**
 244 *	ata_port_desc - append port description
 245 *	@ap: target ATA port
 246 *	@fmt: printf format string
 247 *
 248 *	Format string according to @fmt and append it to port
 249 *	description.  If port description is not empty, " " is added
 250 *	in-between.  This function is to be used while initializing
 251 *	ata_host.  The description is printed on host registration.
 252 *
 253 *	LOCKING:
 254 *	None.
 255 */
 256void ata_port_desc(struct ata_port *ap, const char *fmt, ...)
 257{
 258	va_list args;
 259
 260	WARN_ON(!(ap->pflags & ATA_PFLAG_INITIALIZING));
 261
 262	if (ap->link.eh_info.desc_len)
 263		__ata_ehi_push_desc(&ap->link.eh_info, " ");
 264
 265	va_start(args, fmt);
 266	__ata_ehi_pushv_desc(&ap->link.eh_info, fmt, args);
 267	va_end(args);
 268}
 
 269
 270#ifdef CONFIG_PCI
 271
 272/**
 273 *	ata_port_pbar_desc - append PCI BAR description
 274 *	@ap: target ATA port
 275 *	@bar: target PCI BAR
 276 *	@offset: offset into PCI BAR
 277 *	@name: name of the area
 278 *
 279 *	If @offset is negative, this function formats a string which
 280 *	contains the name, address, size and type of the BAR and
 281 *	appends it to the port description.  If @offset is zero or
 282 *	positive, only name and offsetted address is appended.
 283 *
 284 *	LOCKING:
 285 *	None.
 286 */
 287void ata_port_pbar_desc(struct ata_port *ap, int bar, ssize_t offset,
 288			const char *name)
 289{
 290	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 291	char *type = "";
 292	unsigned long long start, len;
 293
 294	if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
 295		type = "m";
 296	else if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
 297		type = "i";
 298
 299	start = (unsigned long long)pci_resource_start(pdev, bar);
 300	len = (unsigned long long)pci_resource_len(pdev, bar);
 301
 302	if (offset < 0)
 303		ata_port_desc(ap, "%s %s%llu@0x%llx", name, type, len, start);
 304	else
 305		ata_port_desc(ap, "%s 0x%llx", name,
 306				start + (unsigned long long)offset);
 307}
 308
 309#endif /* CONFIG_PCI */
 310
 311static int ata_lookup_timeout_table(u8 cmd)
 312{
 313	int i;
 314
 315	for (i = 0; i < ATA_EH_CMD_TIMEOUT_TABLE_SIZE; i++) {
 316		const u8 *cur;
 317
 318		for (cur = ata_eh_cmd_timeout_table[i].commands; *cur; cur++)
 319			if (*cur == cmd)
 320				return i;
 321	}
 322
 323	return -1;
 324}
 325
 326/**
 327 *	ata_internal_cmd_timeout - determine timeout for an internal command
 328 *	@dev: target device
 329 *	@cmd: internal command to be issued
 330 *
 331 *	Determine timeout for internal command @cmd for @dev.
 332 *
 333 *	LOCKING:
 334 *	EH context.
 335 *
 336 *	RETURNS:
 337 *	Determined timeout.
 338 */
 339unsigned long ata_internal_cmd_timeout(struct ata_device *dev, u8 cmd)
 340{
 341	struct ata_eh_context *ehc = &dev->link->eh_context;
 342	int ent = ata_lookup_timeout_table(cmd);
 343	int idx;
 344
 345	if (ent < 0)
 346		return ATA_EH_CMD_DFL_TIMEOUT;
 347
 348	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 349	return ata_eh_cmd_timeout_table[ent].timeouts[idx];
 350}
 351
 352/**
 353 *	ata_internal_cmd_timed_out - notification for internal command timeout
 354 *	@dev: target device
 355 *	@cmd: internal command which timed out
 356 *
 357 *	Notify EH that internal command @cmd for @dev timed out.  This
 358 *	function should be called only for commands whose timeouts are
 359 *	determined using ata_internal_cmd_timeout().
 360 *
 361 *	LOCKING:
 362 *	EH context.
 363 */
 364void ata_internal_cmd_timed_out(struct ata_device *dev, u8 cmd)
 365{
 366	struct ata_eh_context *ehc = &dev->link->eh_context;
 367	int ent = ata_lookup_timeout_table(cmd);
 368	int idx;
 369
 370	if (ent < 0)
 371		return;
 372
 373	idx = ehc->cmd_timeout_idx[dev->devno][ent];
 374	if (ata_eh_cmd_timeout_table[ent].timeouts[idx + 1] != ULONG_MAX)
 375		ehc->cmd_timeout_idx[dev->devno][ent]++;
 376}
 377
 378static void ata_ering_record(struct ata_ering *ering, unsigned int eflags,
 379			     unsigned int err_mask)
 380{
 381	struct ata_ering_entry *ent;
 382
 383	WARN_ON(!err_mask);
 384
 385	ering->cursor++;
 386	ering->cursor %= ATA_ERING_SIZE;
 387
 388	ent = &ering->ring[ering->cursor];
 389	ent->eflags = eflags;
 390	ent->err_mask = err_mask;
 391	ent->timestamp = get_jiffies_64();
 392}
 393
 394static struct ata_ering_entry *ata_ering_top(struct ata_ering *ering)
 395{
 396	struct ata_ering_entry *ent = &ering->ring[ering->cursor];
 397
 398	if (ent->err_mask)
 399		return ent;
 400	return NULL;
 401}
 402
 403int ata_ering_map(struct ata_ering *ering,
 404		  int (*map_fn)(struct ata_ering_entry *, void *),
 405		  void *arg)
 406{
 407	int idx, rc = 0;
 408	struct ata_ering_entry *ent;
 409
 410	idx = ering->cursor;
 411	do {
 412		ent = &ering->ring[idx];
 413		if (!ent->err_mask)
 414			break;
 415		rc = map_fn(ent, arg);
 416		if (rc)
 417			break;
 418		idx = (idx - 1 + ATA_ERING_SIZE) % ATA_ERING_SIZE;
 419	} while (idx != ering->cursor);
 420
 421	return rc;
 422}
 423
 424static int ata_ering_clear_cb(struct ata_ering_entry *ent, void *void_arg)
 425{
 426	ent->eflags |= ATA_EFLAG_OLD_ER;
 427	return 0;
 428}
 429
 430static void ata_ering_clear(struct ata_ering *ering)
 431{
 432	ata_ering_map(ering, ata_ering_clear_cb, NULL);
 433}
 434
 435static unsigned int ata_eh_dev_action(struct ata_device *dev)
 436{
 437	struct ata_eh_context *ehc = &dev->link->eh_context;
 438
 439	return ehc->i.action | ehc->i.dev_action[dev->devno];
 440}
 441
 442static void ata_eh_clear_action(struct ata_link *link, struct ata_device *dev,
 443				struct ata_eh_info *ehi, unsigned int action)
 444{
 445	struct ata_device *tdev;
 446
 447	if (!dev) {
 448		ehi->action &= ~action;
 449		ata_for_each_dev(tdev, link, ALL)
 450			ehi->dev_action[tdev->devno] &= ~action;
 451	} else {
 452		/* doesn't make sense for port-wide EH actions */
 453		WARN_ON(!(action & ATA_EH_PERDEV_MASK));
 454
 455		/* break ehi->action into ehi->dev_action */
 456		if (ehi->action & action) {
 457			ata_for_each_dev(tdev, link, ALL)
 458				ehi->dev_action[tdev->devno] |=
 459					ehi->action & action;
 460			ehi->action &= ~action;
 461		}
 462
 463		/* turn off the specified per-dev action */
 464		ehi->dev_action[dev->devno] &= ~action;
 465	}
 466}
 467
 468/**
 469 *	ata_eh_acquire - acquire EH ownership
 470 *	@ap: ATA port to acquire EH ownership for
 471 *
 472 *	Acquire EH ownership for @ap.  This is the basic exclusion
 473 *	mechanism for ports sharing a host.  Only one port hanging off
 474 *	the same host can claim the ownership of EH.
 475 *
 476 *	LOCKING:
 477 *	EH context.
 478 */
 479void ata_eh_acquire(struct ata_port *ap)
 480{
 481	mutex_lock(&ap->host->eh_mutex);
 482	WARN_ON_ONCE(ap->host->eh_owner);
 483	ap->host->eh_owner = current;
 484}
 485
 486/**
 487 *	ata_eh_release - release EH ownership
 488 *	@ap: ATA port to release EH ownership for
 489 *
 490 *	Release EH ownership for @ap if the caller.  The caller must
 491 *	have acquired EH ownership using ata_eh_acquire() previously.
 492 *
 493 *	LOCKING:
 494 *	EH context.
 495 */
 496void ata_eh_release(struct ata_port *ap)
 497{
 498	WARN_ON_ONCE(ap->host->eh_owner != current);
 499	ap->host->eh_owner = NULL;
 500	mutex_unlock(&ap->host->eh_mutex);
 501}
 502
 503/**
 504 *	ata_scsi_timed_out - SCSI layer time out callback
 505 *	@cmd: timed out SCSI command
 506 *
 507 *	Handles SCSI layer timeout.  We race with normal completion of
 508 *	the qc for @cmd.  If the qc is already gone, we lose and let
 509 *	the scsi command finish (EH_HANDLED).  Otherwise, the qc has
 510 *	timed out and EH should be invoked.  Prevent ata_qc_complete()
 511 *	from finishing it by setting EH_SCHEDULED and return
 512 *	EH_NOT_HANDLED.
 513 *
 514 *	TODO: kill this function once old EH is gone.
 515 *
 516 *	LOCKING:
 517 *	Called from timer context
 518 *
 519 *	RETURNS:
 520 *	EH_HANDLED or EH_NOT_HANDLED
 521 */
 522enum blk_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd)
 523{
 524	struct Scsi_Host *host = cmd->device->host;
 525	struct ata_port *ap = ata_shost_to_port(host);
 526	unsigned long flags;
 527	struct ata_queued_cmd *qc;
 528	enum blk_eh_timer_return ret;
 529
 530	DPRINTK("ENTER\n");
 531
 532	if (ap->ops->error_handler) {
 533		ret = BLK_EH_NOT_HANDLED;
 534		goto out;
 535	}
 536
 537	ret = BLK_EH_HANDLED;
 538	spin_lock_irqsave(ap->lock, flags);
 539	qc = ata_qc_from_tag(ap, ap->link.active_tag);
 540	if (qc) {
 541		WARN_ON(qc->scsicmd != cmd);
 542		qc->flags |= ATA_QCFLAG_EH_SCHEDULED;
 543		qc->err_mask |= AC_ERR_TIMEOUT;
 544		ret = BLK_EH_NOT_HANDLED;
 545	}
 546	spin_unlock_irqrestore(ap->lock, flags);
 547
 548 out:
 549	DPRINTK("EXIT, ret=%d\n", ret);
 550	return ret;
 
 551}
 552
 553static void ata_eh_unload(struct ata_port *ap)
 554{
 555	struct ata_link *link;
 556	struct ata_device *dev;
 557	unsigned long flags;
 558
 559	/* Restore SControl IPM and SPD for the next driver and
 
 
 
 
 
 
 
 
 
 
 
 
 560	 * disable attached devices.
 561	 */
 562	ata_for_each_link(link, ap, PMP_FIRST) {
 563		sata_scr_write(link, SCR_CONTROL, link->saved_scontrol & 0xff0);
 564		ata_for_each_dev(dev, link, ALL)
 565			ata_dev_disable(dev);
 566	}
 567
 568	/* freeze and set UNLOADED */
 569	spin_lock_irqsave(ap->lock, flags);
 570
 571	ata_port_freeze(ap);			/* won't be thawed */
 572	ap->pflags &= ~ATA_PFLAG_EH_PENDING;	/* clear pending from freeze */
 573	ap->pflags |= ATA_PFLAG_UNLOADED;
 574
 575	spin_unlock_irqrestore(ap->lock, flags);
 576}
 577
 578/**
 579 *	ata_scsi_error - SCSI layer error handler callback
 580 *	@host: SCSI host on which error occurred
 581 *
 582 *	Handles SCSI-layer-thrown error events.
 583 *
 584 *	LOCKING:
 585 *	Inherited from SCSI layer (none, can sleep)
 586 *
 587 *	RETURNS:
 588 *	Zero.
 589 */
 590void ata_scsi_error(struct Scsi_Host *host)
 591{
 592	struct ata_port *ap = ata_shost_to_port(host);
 593	unsigned long flags;
 594	LIST_HEAD(eh_work_q);
 595
 596	DPRINTK("ENTER\n");
 597
 598	spin_lock_irqsave(host->host_lock, flags);
 599	list_splice_init(&host->eh_cmd_q, &eh_work_q);
 600	spin_unlock_irqrestore(host->host_lock, flags);
 601
 602	ata_scsi_cmd_error_handler(host, ap, &eh_work_q);
 603
 604	/* If we timed raced normal completion and there is nothing to
 605	   recover nr_timedout == 0 why exactly are we doing error recovery ? */
 606	ata_scsi_port_error_handler(host, ap);
 607
 608	/* finish or retry handled scmd's and clean up */
 609	WARN_ON(host->host_failed || !list_empty(&eh_work_q));
 610
 611	DPRINTK("EXIT\n");
 612}
 613
 614/**
 615 * ata_scsi_cmd_error_handler - error callback for a list of commands
 616 * @host:	scsi host containing the port
 617 * @ap:		ATA port within the host
 618 * @eh_work_q:	list of commands to process
 619 *
 620 * process the given list of commands and return those finished to the
 621 * ap->eh_done_q.  This function is the first part of the libata error
 622 * handler which processes a given list of failed commands.
 623 */
 624void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
 625				struct list_head *eh_work_q)
 626{
 627	int i;
 628	unsigned long flags;
 
 
 629
 630	/* make sure sff pio task is not running */
 631	ata_sff_flush_pio_task(ap);
 632
 633	/* synchronize with host lock and sort out timeouts */
 634
 635	/* For new EH, all qcs are finished in one of three ways -
 
 636	 * normal completion, error completion, and SCSI timeout.
 637	 * Both completions can race against SCSI timeout.  When normal
 638	 * completion wins, the qc never reaches EH.  When error
 639	 * completion wins, the qc has ATA_QCFLAG_FAILED set.
 640	 *
 641	 * When SCSI timeout wins, things are a bit more complex.
 642	 * Normal or error completion can occur after the timeout but
 643	 * before this point.  In such cases, both types of
 644	 * completions are honored.  A scmd is determined to have
 645	 * timed out iff its associated qc is active and not failed.
 646	 */
 647	if (ap->ops->error_handler) {
 648		struct scsi_cmnd *scmd, *tmp;
 649		int nr_timedout = 0;
 650
 651		spin_lock_irqsave(ap->lock, flags);
 652
 653		/* This must occur under the ap->lock as we don't want
 654		   a polled recovery to race the real interrupt handler
 655
 656		   The lost_interrupt handler checks for any completed but
 657		   non-notified command and completes much like an IRQ handler.
 
 
 
 
 
 
 
 
 
 
 658
 659		   We then fall into the error recovery code which will treat
 660		   this as if normal completion won the race */
 661
 662		if (ap->ops->lost_interrupt)
 663			ap->ops->lost_interrupt(ap);
 664
 665		list_for_each_entry_safe(scmd, tmp, eh_work_q, eh_entry) {
 666			struct ata_queued_cmd *qc;
 667
 668			for (i = 0; i < ATA_MAX_QUEUE; i++) {
 669				qc = __ata_qc_from_tag(ap, i);
 670				if (qc->flags & ATA_QCFLAG_ACTIVE &&
 671				    qc->scsicmd == scmd)
 672					break;
 673			}
 674
 675			if (i < ATA_MAX_QUEUE) {
 676				/* the scmd has an associated qc */
 677				if (!(qc->flags & ATA_QCFLAG_FAILED)) {
 678					/* which hasn't failed yet, timeout */
 679					qc->err_mask |= AC_ERR_TIMEOUT;
 680					qc->flags |= ATA_QCFLAG_FAILED;
 681					nr_timedout++;
 682				}
 683			} else {
 684				/* Normal completion occurred after
 685				 * SCSI timeout but before this point.
 686				 * Successfully complete it.
 687				 */
 688				scmd->retries = scmd->allowed;
 689				scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
 690			}
 
 
 
 
 
 
 
 691		}
 
 692
 693		/* If we have timed out qcs.  They belong to EH from
 694		 * this point but the state of the controller is
 695		 * unknown.  Freeze the port to make sure the IRQ
 696		 * handler doesn't diddle with those qcs.  This must
 697		 * be done atomically w.r.t. setting QCFLAG_FAILED.
 698		 */
 699		if (nr_timedout)
 700			__ata_port_freeze(ap);
 701
 702		spin_unlock_irqrestore(ap->lock, flags);
 703
 704		/* initialize eh_tries */
 705		ap->eh_tries = ATA_EH_MAX_TRIES;
 706	} else
 707		spin_unlock_wait(ap->lock);
 708
 
 709}
 710EXPORT_SYMBOL(ata_scsi_cmd_error_handler);
 711
 712/**
 713 * ata_scsi_port_error_handler - recover the port after the commands
 714 * @host:	SCSI host containing the port
 715 * @ap:		the ATA port
 716 *
 717 * Handle the recovery of the port @ap after all the commands
 718 * have been recovered.
 719 */
 720void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap)
 721{
 722	unsigned long flags;
 
 723
 724	/* invoke error handler */
 725	if (ap->ops->error_handler) {
 726		struct ata_link *link;
 727
 728		/* acquire EH ownership */
 729		ata_eh_acquire(ap);
 730 repeat:
 731		/* kill fast drain timer */
 732		del_timer_sync(&ap->fastdrain_timer);
 733
 734		/* process port resume request */
 735		ata_eh_handle_port_resume(ap);
 736
 737		/* fetch & clear EH info */
 738		spin_lock_irqsave(ap->lock, flags);
 739
 740		ata_for_each_link(link, ap, HOST_FIRST) {
 741			struct ata_eh_context *ehc = &link->eh_context;
 742			struct ata_device *dev;
 743
 744			memset(&link->eh_context, 0, sizeof(link->eh_context));
 745			link->eh_context.i = link->eh_info;
 746			memset(&link->eh_info, 0, sizeof(link->eh_info));
 747
 748			ata_for_each_dev(dev, link, ENABLED) {
 749				int devno = dev->devno;
 750
 751				ehc->saved_xfer_mode[devno] = dev->xfer_mode;
 752				if (ata_ncq_enabled(dev))
 753					ehc->saved_ncq_enabled |= 1 << devno;
 754			}
 755		}
 756
 757		ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
 758		ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 759		ap->excl_link = NULL;	/* don't maintain exclusion over EH */
 760
 761		spin_unlock_irqrestore(ap->lock, flags);
 
 762
 763		/* invoke EH, skip if unloading or suspended */
 764		if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))
 765			ap->ops->error_handler(ap);
 766		else {
 767			/* if unloading, commence suicide */
 768			if ((ap->pflags & ATA_PFLAG_UNLOADING) &&
 769			    !(ap->pflags & ATA_PFLAG_UNLOADED))
 770				ata_eh_unload(ap);
 771			ata_eh_finish(ap);
 772		}
 773
 774		/* process port suspend request */
 775		ata_eh_handle_port_suspend(ap);
 776
 777		/* Exception might have happened after ->error_handler
 778		 * recovered the port but before this point.  Repeat
 779		 * EH in such case.
 780		 */
 781		spin_lock_irqsave(ap->lock, flags);
 782
 783		if (ap->pflags & ATA_PFLAG_EH_PENDING) {
 784			if (--ap->eh_tries) {
 785				spin_unlock_irqrestore(ap->lock, flags);
 786				goto repeat;
 787			}
 788			ata_port_err(ap,
 789				     "EH pending after %d tries, giving up\n",
 790				     ATA_EH_MAX_TRIES);
 791			ap->pflags &= ~ATA_PFLAG_EH_PENDING;
 792		}
 
 793
 794		/* this run is complete, make sure EH info is clear */
 795		ata_for_each_link(link, ap, HOST_FIRST)
 796			memset(&link->eh_info, 0, sizeof(link->eh_info));
 797
 798		/* end eh (clear host_eh_scheduled) while holding
 799		 * ap->lock such that if exception occurs after this
 800		 * point but before EH completion, SCSI midlayer will
 801		 * re-initiate EH.
 802		 */
 803		ap->ops->end_eh(ap);
 804
 805		spin_unlock_irqrestore(ap->lock, flags);
 806		ata_eh_release(ap);
 807	} else {
 808		WARN_ON(ata_qc_from_tag(ap, ap->link.active_tag) == NULL);
 809		ap->ops->eng_timeout(ap);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 810	}
 811
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 812	scsi_eh_flush_done_q(&ap->eh_done_q);
 813
 814	/* clean up */
 815	spin_lock_irqsave(ap->lock, flags);
 816
 
 
 817	if (ap->pflags & ATA_PFLAG_LOADING)
 818		ap->pflags &= ~ATA_PFLAG_LOADING;
 819	else if (ap->pflags & ATA_PFLAG_SCSI_HOTPLUG)
 
 820		schedule_delayed_work(&ap->hotplug_task, 0);
 821
 822	if (ap->pflags & ATA_PFLAG_RECOVERED)
 823		ata_port_info(ap, "EH complete\n");
 824
 825	ap->pflags &= ~(ATA_PFLAG_SCSI_HOTPLUG | ATA_PFLAG_RECOVERED);
 826
 827	/* tell wait_eh that we're done */
 828	ap->pflags &= ~ATA_PFLAG_EH_IN_PROGRESS;
 829	wake_up_all(&ap->eh_wait_q);
 830
 831	spin_unlock_irqrestore(ap->lock, flags);
 832}
 833EXPORT_SYMBOL_GPL(ata_scsi_port_error_handler);
 834
 835/**
 836 *	ata_port_wait_eh - Wait for the currently pending EH to complete
 837 *	@ap: Port to wait EH for
 838 *
 839 *	Wait until the currently pending EH is complete.
 840 *
 841 *	LOCKING:
 842 *	Kernel thread context (may sleep).
 843 */
 844void ata_port_wait_eh(struct ata_port *ap)
 845{
 846	unsigned long flags;
 847	DEFINE_WAIT(wait);
 848
 849 retry:
 850	spin_lock_irqsave(ap->lock, flags);
 851
 852	while (ap->pflags & (ATA_PFLAG_EH_PENDING | ATA_PFLAG_EH_IN_PROGRESS)) {
 853		prepare_to_wait(&ap->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
 854		spin_unlock_irqrestore(ap->lock, flags);
 855		schedule();
 856		spin_lock_irqsave(ap->lock, flags);
 857	}
 858	finish_wait(&ap->eh_wait_q, &wait);
 859
 860	spin_unlock_irqrestore(ap->lock, flags);
 861
 862	/* make sure SCSI EH is complete */
 863	if (scsi_host_in_recovery(ap->scsi_host)) {
 864		ata_msleep(ap, 10);
 865		goto retry;
 866	}
 867}
 868EXPORT_SYMBOL_GPL(ata_port_wait_eh);
 869
 870static int ata_eh_nr_in_flight(struct ata_port *ap)
 871{
 
 872	unsigned int tag;
 873	int nr = 0;
 874
 875	/* count only non-internal commands */
 876	for (tag = 0; tag < ATA_MAX_QUEUE - 1; tag++)
 877		if (ata_qc_from_tag(ap, tag))
 878			nr++;
 
 879
 880	return nr;
 881}
 882
 883void ata_eh_fastdrain_timerfn(unsigned long arg)
 884{
 885	struct ata_port *ap = (void *)arg;
 886	unsigned long flags;
 887	int cnt;
 888
 889	spin_lock_irqsave(ap->lock, flags);
 890
 891	cnt = ata_eh_nr_in_flight(ap);
 892
 893	/* are we done? */
 894	if (!cnt)
 895		goto out_unlock;
 896
 897	if (cnt == ap->fastdrain_cnt) {
 
 898		unsigned int tag;
 899
 900		/* No progress during the last interval, tag all
 901		 * in-flight qcs as timed out and freeze the port.
 902		 */
 903		for (tag = 0; tag < ATA_MAX_QUEUE - 1; tag++) {
 904			struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag);
 905			if (qc)
 906				qc->err_mask |= AC_ERR_TIMEOUT;
 907		}
 908
 909		ata_port_freeze(ap);
 910	} else {
 911		/* some qcs have finished, give it another chance */
 912		ap->fastdrain_cnt = cnt;
 913		ap->fastdrain_timer.expires =
 914			ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 915		add_timer(&ap->fastdrain_timer);
 916	}
 917
 918 out_unlock:
 919	spin_unlock_irqrestore(ap->lock, flags);
 920}
 921
 922/**
 923 *	ata_eh_set_pending - set ATA_PFLAG_EH_PENDING and activate fast drain
 924 *	@ap: target ATA port
 925 *	@fastdrain: activate fast drain
 926 *
 927 *	Set ATA_PFLAG_EH_PENDING and activate fast drain if @fastdrain
 928 *	is non-zero and EH wasn't pending before.  Fast drain ensures
 929 *	that EH kicks in in timely manner.
 930 *
 931 *	LOCKING:
 932 *	spin_lock_irqsave(host lock)
 933 */
 934static void ata_eh_set_pending(struct ata_port *ap, int fastdrain)
 935{
 936	int cnt;
 937
 938	/* already scheduled? */
 939	if (ap->pflags & ATA_PFLAG_EH_PENDING)
 940		return;
 941
 942	ap->pflags |= ATA_PFLAG_EH_PENDING;
 943
 944	if (!fastdrain)
 945		return;
 946
 947	/* do we have in-flight qcs? */
 948	cnt = ata_eh_nr_in_flight(ap);
 949	if (!cnt)
 950		return;
 951
 952	/* activate fast drain */
 953	ap->fastdrain_cnt = cnt;
 954	ap->fastdrain_timer.expires =
 955		ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
 956	add_timer(&ap->fastdrain_timer);
 957}
 958
 959/**
 960 *	ata_qc_schedule_eh - schedule qc for error handling
 961 *	@qc: command to schedule error handling for
 962 *
 963 *	Schedule error handling for @qc.  EH will kick in as soon as
 964 *	other commands are drained.
 965 *
 966 *	LOCKING:
 967 *	spin_lock_irqsave(host lock)
 968 */
 969void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
 970{
 971	struct ata_port *ap = qc->ap;
 972	struct request_queue *q = qc->scsicmd->device->request_queue;
 973	unsigned long flags;
 974
 975	WARN_ON(!ap->ops->error_handler);
 976
 977	qc->flags |= ATA_QCFLAG_FAILED;
 978	ata_eh_set_pending(ap, 1);
 979
 980	/* The following will fail if timeout has already expired.
 981	 * ata_scsi_error() takes care of such scmds on EH entry.
 982	 * Note that ATA_QCFLAG_FAILED is unconditionally set after
 983	 * this function completes.
 984	 */
 985	spin_lock_irqsave(q->queue_lock, flags);
 986	blk_abort_request(qc->scsicmd->request);
 987	spin_unlock_irqrestore(q->queue_lock, flags);
 988}
 989
 990/**
 991 * ata_std_sched_eh - non-libsas ata_ports issue eh with this common routine
 992 * @ap: ATA port to schedule EH for
 993 *
 994 *	LOCKING: inherited from ata_port_schedule_eh
 995 *	spin_lock_irqsave(host lock)
 996 */
 997void ata_std_sched_eh(struct ata_port *ap)
 998{
 999	WARN_ON(!ap->ops->error_handler);
1000
1001	if (ap->pflags & ATA_PFLAG_INITIALIZING)
1002		return;
1003
1004	ata_eh_set_pending(ap, 1);
1005	scsi_schedule_eh(ap->scsi_host);
1006
1007	DPRINTK("port EH scheduled\n");
1008}
1009EXPORT_SYMBOL_GPL(ata_std_sched_eh);
1010
1011/**
1012 * ata_std_end_eh - non-libsas ata_ports complete eh with this common routine
1013 * @ap: ATA port to end EH for
1014 *
1015 * In the libata object model there is a 1:1 mapping of ata_port to
1016 * shost, so host fields can be directly manipulated under ap->lock, in
1017 * the libsas case we need to hold a lock at the ha->level to coordinate
1018 * these events.
1019 *
1020 *	LOCKING:
1021 *	spin_lock_irqsave(host lock)
1022 */
1023void ata_std_end_eh(struct ata_port *ap)
1024{
1025	struct Scsi_Host *host = ap->scsi_host;
1026
1027	host->host_eh_scheduled = 0;
1028}
1029EXPORT_SYMBOL(ata_std_end_eh);
1030
1031
1032/**
1033 *	ata_port_schedule_eh - schedule error handling without a qc
1034 *	@ap: ATA port to schedule EH for
1035 *
1036 *	Schedule error handling for @ap.  EH will kick in as soon as
1037 *	all commands are drained.
1038 *
1039 *	LOCKING:
1040 *	spin_lock_irqsave(host lock)
1041 */
1042void ata_port_schedule_eh(struct ata_port *ap)
1043{
1044	/* see: ata_std_sched_eh, unless you know better */
1045	ap->ops->sched_eh(ap);
1046}
 
1047
1048static int ata_do_link_abort(struct ata_port *ap, struct ata_link *link)
1049{
 
1050	int tag, nr_aborted = 0;
1051
1052	WARN_ON(!ap->ops->error_handler);
1053
1054	/* we're gonna abort all commands, no need for fast drain */
1055	ata_eh_set_pending(ap, 0);
1056
1057	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
1058		struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag);
1059
1060		if (qc && (!link || qc->dev->link == link)) {
1061			qc->flags |= ATA_QCFLAG_FAILED;
1062			ata_qc_complete(qc);
1063			nr_aborted++;
1064		}
1065	}
1066
1067	if (!nr_aborted)
1068		ata_port_schedule_eh(ap);
1069
1070	return nr_aborted;
1071}
1072
1073/**
1074 *	ata_link_abort - abort all qc's on the link
1075 *	@link: ATA link to abort qc's for
1076 *
1077 *	Abort all active qc's active on @link and schedule EH.
1078 *
1079 *	LOCKING:
1080 *	spin_lock_irqsave(host lock)
1081 *
1082 *	RETURNS:
1083 *	Number of aborted qc's.
1084 */
1085int ata_link_abort(struct ata_link *link)
1086{
1087	return ata_do_link_abort(link->ap, link);
1088}
 
1089
1090/**
1091 *	ata_port_abort - abort all qc's on the port
1092 *	@ap: ATA port to abort qc's for
1093 *
1094 *	Abort all active qc's of @ap and schedule EH.
1095 *
1096 *	LOCKING:
1097 *	spin_lock_irqsave(host_set lock)
1098 *
1099 *	RETURNS:
1100 *	Number of aborted qc's.
1101 */
1102int ata_port_abort(struct ata_port *ap)
1103{
1104	return ata_do_link_abort(ap, NULL);
1105}
 
1106
1107/**
1108 *	__ata_port_freeze - freeze port
1109 *	@ap: ATA port to freeze
1110 *
1111 *	This function is called when HSM violation or some other
1112 *	condition disrupts normal operation of the port.  Frozen port
1113 *	is not allowed to perform any operation until the port is
1114 *	thawed, which usually follows a successful reset.
1115 *
1116 *	ap->ops->freeze() callback can be used for freezing the port
1117 *	hardware-wise (e.g. mask interrupt and stop DMA engine).  If a
1118 *	port cannot be frozen hardware-wise, the interrupt handler
1119 *	must ack and clear interrupts unconditionally while the port
1120 *	is frozen.
1121 *
1122 *	LOCKING:
1123 *	spin_lock_irqsave(host lock)
1124 */
1125static void __ata_port_freeze(struct ata_port *ap)
1126{
1127	WARN_ON(!ap->ops->error_handler);
1128
1129	if (ap->ops->freeze)
1130		ap->ops->freeze(ap);
1131
1132	ap->pflags |= ATA_PFLAG_FROZEN;
1133
1134	DPRINTK("ata%u port frozen\n", ap->print_id);
1135}
1136
1137/**
1138 *	ata_port_freeze - abort & freeze port
1139 *	@ap: ATA port to freeze
1140 *
1141 *	Abort and freeze @ap.  The freeze operation must be called
1142 *	first, because some hardware requires special operations
1143 *	before the taskfile registers are accessible.
1144 *
1145 *	LOCKING:
1146 *	spin_lock_irqsave(host lock)
1147 *
1148 *	RETURNS:
1149 *	Number of aborted commands.
1150 */
1151int ata_port_freeze(struct ata_port *ap)
1152{
1153	int nr_aborted;
1154
1155	WARN_ON(!ap->ops->error_handler);
1156
1157	__ata_port_freeze(ap);
1158	nr_aborted = ata_port_abort(ap);
1159
1160	return nr_aborted;
1161}
1162
1163/**
1164 *	sata_async_notification - SATA async notification handler
1165 *	@ap: ATA port where async notification is received
1166 *
1167 *	Handler to be called when async notification via SDB FIS is
1168 *	received.  This function schedules EH if necessary.
1169 *
1170 *	LOCKING:
1171 *	spin_lock_irqsave(host lock)
1172 *
1173 *	RETURNS:
1174 *	1 if EH is scheduled, 0 otherwise.
1175 */
1176int sata_async_notification(struct ata_port *ap)
1177{
1178	u32 sntf;
1179	int rc;
1180
1181	if (!(ap->flags & ATA_FLAG_AN))
1182		return 0;
1183
1184	rc = sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf);
1185	if (rc == 0)
1186		sata_scr_write(&ap->link, SCR_NOTIFICATION, sntf);
1187
1188	if (!sata_pmp_attached(ap) || rc) {
1189		/* PMP is not attached or SNTF is not available */
1190		if (!sata_pmp_attached(ap)) {
1191			/* PMP is not attached.  Check whether ATAPI
1192			 * AN is configured.  If so, notify media
1193			 * change.
1194			 */
1195			struct ata_device *dev = ap->link.device;
1196
1197			if ((dev->class == ATA_DEV_ATAPI) &&
1198			    (dev->flags & ATA_DFLAG_AN))
1199				ata_scsi_media_change_notify(dev);
1200			return 0;
1201		} else {
1202			/* PMP is attached but SNTF is not available.
1203			 * ATAPI async media change notification is
1204			 * not used.  The PMP must be reporting PHY
1205			 * status change, schedule EH.
1206			 */
1207			ata_port_schedule_eh(ap);
1208			return 1;
1209		}
1210	} else {
1211		/* PMP is attached and SNTF is available */
1212		struct ata_link *link;
1213
1214		/* check and notify ATAPI AN */
1215		ata_for_each_link(link, ap, EDGE) {
1216			if (!(sntf & (1 << link->pmp)))
1217				continue;
1218
1219			if ((link->device->class == ATA_DEV_ATAPI) &&
1220			    (link->device->flags & ATA_DFLAG_AN))
1221				ata_scsi_media_change_notify(link->device);
1222		}
1223
1224		/* If PMP is reporting that PHY status of some
1225		 * downstream ports has changed, schedule EH.
1226		 */
1227		if (sntf & (1 << SATA_PMP_CTRL_PORT)) {
1228			ata_port_schedule_eh(ap);
1229			return 1;
1230		}
1231
1232		return 0;
1233	}
1234}
 
1235
1236/**
1237 *	ata_eh_freeze_port - EH helper to freeze port
1238 *	@ap: ATA port to freeze
1239 *
1240 *	Freeze @ap.
1241 *
1242 *	LOCKING:
1243 *	None.
1244 */
1245void ata_eh_freeze_port(struct ata_port *ap)
1246{
1247	unsigned long flags;
1248
1249	if (!ap->ops->error_handler)
1250		return;
1251
1252	spin_lock_irqsave(ap->lock, flags);
1253	__ata_port_freeze(ap);
1254	spin_unlock_irqrestore(ap->lock, flags);
1255}
 
1256
1257/**
1258 *	ata_port_thaw_port - EH helper to thaw port
1259 *	@ap: ATA port to thaw
1260 *
1261 *	Thaw frozen port @ap.
1262 *
1263 *	LOCKING:
1264 *	None.
1265 */
1266void ata_eh_thaw_port(struct ata_port *ap)
1267{
1268	unsigned long flags;
1269
1270	if (!ap->ops->error_handler)
1271		return;
1272
1273	spin_lock_irqsave(ap->lock, flags);
1274
1275	ap->pflags &= ~ATA_PFLAG_FROZEN;
1276
1277	if (ap->ops->thaw)
1278		ap->ops->thaw(ap);
1279
1280	spin_unlock_irqrestore(ap->lock, flags);
1281
1282	DPRINTK("ata%u port thawed\n", ap->print_id);
1283}
1284
1285static void ata_eh_scsidone(struct scsi_cmnd *scmd)
1286{
1287	/* nada */
1288}
1289
1290static void __ata_eh_qc_complete(struct ata_queued_cmd *qc)
1291{
1292	struct ata_port *ap = qc->ap;
1293	struct scsi_cmnd *scmd = qc->scsicmd;
1294	unsigned long flags;
1295
1296	spin_lock_irqsave(ap->lock, flags);
1297	qc->scsidone = ata_eh_scsidone;
1298	__ata_qc_complete(qc);
1299	WARN_ON(ata_tag_valid(qc->tag));
1300	spin_unlock_irqrestore(ap->lock, flags);
1301
1302	scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
1303}
1304
1305/**
1306 *	ata_eh_qc_complete - Complete an active ATA command from EH
1307 *	@qc: Command to complete
1308 *
1309 *	Indicate to the mid and upper layers that an ATA command has
1310 *	completed.  To be used from EH.
1311 */
1312void ata_eh_qc_complete(struct ata_queued_cmd *qc)
1313{
1314	struct scsi_cmnd *scmd = qc->scsicmd;
1315	scmd->retries = scmd->allowed;
1316	__ata_eh_qc_complete(qc);
1317}
1318
1319/**
1320 *	ata_eh_qc_retry - Tell midlayer to retry an ATA command after EH
1321 *	@qc: Command to retry
1322 *
1323 *	Indicate to the mid and upper layers that an ATA command
1324 *	should be retried.  To be used from EH.
1325 *
1326 *	SCSI midlayer limits the number of retries to scmd->allowed.
1327 *	scmd->allowed is incremented for commands which get retried
1328 *	due to unrelated failures (qc->err_mask is zero).
1329 */
1330void ata_eh_qc_retry(struct ata_queued_cmd *qc)
1331{
1332	struct scsi_cmnd *scmd = qc->scsicmd;
1333	if (!qc->err_mask)
1334		scmd->allowed++;
1335	__ata_eh_qc_complete(qc);
1336}
1337
1338/**
1339 *	ata_dev_disable - disable ATA device
1340 *	@dev: ATA device to disable
1341 *
1342 *	Disable @dev.
1343 *
1344 *	Locking:
1345 *	EH context.
1346 */
1347void ata_dev_disable(struct ata_device *dev)
1348{
1349	if (!ata_dev_enabled(dev))
1350		return;
1351
1352	if (ata_msg_drv(dev->link->ap))
1353		ata_dev_warn(dev, "disabled\n");
1354	ata_acpi_on_disable(dev);
1355	ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 | ATA_DNXFER_QUIET);
1356	dev->class++;
1357
1358	/* From now till the next successful probe, ering is used to
1359	 * track probe failures.  Clear accumulated device error info.
1360	 */
1361	ata_ering_clear(&dev->ering);
1362}
 
1363
1364/**
1365 *	ata_eh_detach_dev - detach ATA device
1366 *	@dev: ATA device to detach
1367 *
1368 *	Detach @dev.
1369 *
1370 *	LOCKING:
1371 *	None.
1372 */
1373void ata_eh_detach_dev(struct ata_device *dev)
1374{
1375	struct ata_link *link = dev->link;
1376	struct ata_port *ap = link->ap;
1377	struct ata_eh_context *ehc = &link->eh_context;
1378	unsigned long flags;
1379
1380	ata_dev_disable(dev);
 
 
 
 
 
 
 
1381
1382	spin_lock_irqsave(ap->lock, flags);
1383
1384	dev->flags &= ~ATA_DFLAG_DETACH;
1385
1386	if (ata_scsi_offline_dev(dev)) {
1387		dev->flags |= ATA_DFLAG_DETACHED;
1388		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
1389	}
1390
1391	/* clear per-dev EH info */
1392	ata_eh_clear_action(link, dev, &link->eh_info, ATA_EH_PERDEV_MASK);
1393	ata_eh_clear_action(link, dev, &link->eh_context.i, ATA_EH_PERDEV_MASK);
1394	ehc->saved_xfer_mode[dev->devno] = 0;
1395	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
1396
1397	spin_unlock_irqrestore(ap->lock, flags);
1398}
1399
1400/**
1401 *	ata_eh_about_to_do - about to perform eh_action
1402 *	@link: target ATA link
1403 *	@dev: target ATA dev for per-dev action (can be NULL)
1404 *	@action: action about to be performed
1405 *
1406 *	Called just before performing EH actions to clear related bits
1407 *	in @link->eh_info such that eh actions are not unnecessarily
1408 *	repeated.
1409 *
1410 *	LOCKING:
1411 *	None.
1412 */
1413void ata_eh_about_to_do(struct ata_link *link, struct ata_device *dev,
1414			unsigned int action)
1415{
1416	struct ata_port *ap = link->ap;
1417	struct ata_eh_info *ehi = &link->eh_info;
1418	struct ata_eh_context *ehc = &link->eh_context;
1419	unsigned long flags;
1420
 
 
1421	spin_lock_irqsave(ap->lock, flags);
1422
1423	ata_eh_clear_action(link, dev, ehi, action);
1424
1425	/* About to take EH action, set RECOVERED.  Ignore actions on
1426	 * slave links as master will do them again.
1427	 */
1428	if (!(ehc->i.flags & ATA_EHI_QUIET) && link != ap->slave_link)
1429		ap->pflags |= ATA_PFLAG_RECOVERED;
1430
1431	spin_unlock_irqrestore(ap->lock, flags);
1432}
1433
1434/**
1435 *	ata_eh_done - EH action complete
1436*	@ap: target ATA port
1437 *	@dev: target ATA dev for per-dev action (can be NULL)
1438 *	@action: action just completed
1439 *
1440 *	Called right after performing EH actions to clear related bits
1441 *	in @link->eh_context.
1442 *
1443 *	LOCKING:
1444 *	None.
1445 */
1446void ata_eh_done(struct ata_link *link, struct ata_device *dev,
1447		 unsigned int action)
1448{
1449	struct ata_eh_context *ehc = &link->eh_context;
1450
 
 
1451	ata_eh_clear_action(link, dev, &ehc->i, action);
1452}
1453
1454/**
1455 *	ata_err_string - convert err_mask to descriptive string
1456 *	@err_mask: error mask to convert to string
1457 *
1458 *	Convert @err_mask to descriptive string.  Errors are
1459 *	prioritized according to severity and only the most severe
1460 *	error is reported.
1461 *
1462 *	LOCKING:
1463 *	None.
1464 *
1465 *	RETURNS:
1466 *	Descriptive string for @err_mask
1467 */
1468static const char *ata_err_string(unsigned int err_mask)
1469{
1470	if (err_mask & AC_ERR_HOST_BUS)
1471		return "host bus error";
1472	if (err_mask & AC_ERR_ATA_BUS)
1473		return "ATA bus error";
1474	if (err_mask & AC_ERR_TIMEOUT)
1475		return "timeout";
1476	if (err_mask & AC_ERR_HSM)
1477		return "HSM violation";
1478	if (err_mask & AC_ERR_SYSTEM)
1479		return "internal error";
1480	if (err_mask & AC_ERR_MEDIA)
1481		return "media error";
1482	if (err_mask & AC_ERR_INVALID)
1483		return "invalid argument";
1484	if (err_mask & AC_ERR_DEV)
1485		return "device error";
 
 
 
 
1486	return "unknown error";
1487}
1488
1489/**
1490 *	ata_read_log_page - read a specific log page
1491 *	@dev: target device
1492 *	@log: log to read
1493 *	@page: page to read
1494 *	@buf: buffer to store read page
1495 *	@sectors: number of sectors to read
1496 *
1497 *	Read log page using READ_LOG_EXT command.
1498 *
1499 *	LOCKING:
1500 *	Kernel thread context (may sleep).
1501 *
1502 *	RETURNS:
1503 *	0 on success, AC_ERR_* mask otherwise.
1504 */
1505unsigned int ata_read_log_page(struct ata_device *dev, u8 log,
1506			       u8 page, void *buf, unsigned int sectors)
1507{
1508	unsigned long ap_flags = dev->link->ap->flags;
1509	struct ata_taskfile tf;
1510	unsigned int err_mask;
1511	bool dma = false;
1512
1513	DPRINTK("read log page - log 0x%x, page 0x%x\n", log, page);
1514
1515	/*
1516	 * Return error without actually issuing the command on controllers
1517	 * which e.g. lockup on a read log page.
1518	 */
1519	if (ap_flags & ATA_FLAG_NO_LOG_PAGE)
1520		return AC_ERR_DEV;
1521
1522retry:
1523	ata_tf_init(dev, &tf);
1524	if (dev->dma_mode && ata_id_has_read_log_dma_ext(dev->id) &&
1525	    !(dev->horkage & ATA_HORKAGE_NO_NCQ_LOG)) {
1526		tf.command = ATA_CMD_READ_LOG_DMA_EXT;
1527		tf.protocol = ATA_PROT_DMA;
1528		dma = true;
1529	} else {
1530		tf.command = ATA_CMD_READ_LOG_EXT;
1531		tf.protocol = ATA_PROT_PIO;
1532		dma = false;
1533	}
1534	tf.lbal = log;
1535	tf.lbam = page;
1536	tf.nsect = sectors;
1537	tf.hob_nsect = sectors >> 8;
1538	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_LBA48 | ATA_TFLAG_DEVICE;
1539
1540	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_FROM_DEVICE,
1541				     buf, sectors * ATA_SECT_SIZE, 0);
1542
1543	if (err_mask && dma) {
1544		dev->horkage |= ATA_HORKAGE_NO_NCQ_LOG;
1545		ata_dev_warn(dev, "READ LOG DMA EXT failed, trying unqueued\n");
1546		goto retry;
1547	}
1548
1549	DPRINTK("EXIT, err_mask=%x\n", err_mask);
 
 
 
 
 
 
1550	return err_mask;
1551}
1552
1553/**
1554 *	ata_eh_read_log_10h - Read log page 10h for NCQ error details
1555 *	@dev: Device to read log page 10h from
1556 *	@tag: Resulting tag of the failed command
1557 *	@tf: Resulting taskfile registers of the failed command
1558 *
1559 *	Read log page 10h to obtain NCQ error details and clear error
1560 *	condition.
1561 *
1562 *	LOCKING:
1563 *	Kernel thread context (may sleep).
1564 *
1565 *	RETURNS:
1566 *	0 on success, -errno otherwise.
1567 */
1568static int ata_eh_read_log_10h(struct ata_device *dev,
1569			       int *tag, struct ata_taskfile *tf)
1570{
1571	u8 *buf = dev->link->ap->sector_buf;
 
 
1572	unsigned int err_mask;
1573	u8 csum;
1574	int i;
1575
1576	err_mask = ata_read_log_page(dev, ATA_LOG_SATA_NCQ, 0, buf, 1);
1577	if (err_mask)
1578		return -EIO;
1579
1580	csum = 0;
1581	for (i = 0; i < ATA_SECT_SIZE; i++)
1582		csum += buf[i];
1583	if (csum)
1584		ata_dev_warn(dev, "invalid checksum 0x%x on log page 10h\n",
1585			     csum);
1586
1587	if (buf[0] & 0x80)
1588		return -ENOENT;
1589
1590	*tag = buf[0] & 0x1f;
1591
1592	tf->command = buf[2];
1593	tf->feature = buf[3];
1594	tf->lbal = buf[4];
1595	tf->lbam = buf[5];
1596	tf->lbah = buf[6];
1597	tf->device = buf[7];
1598	tf->hob_lbal = buf[8];
1599	tf->hob_lbam = buf[9];
1600	tf->hob_lbah = buf[10];
1601	tf->nsect = buf[12];
1602	tf->hob_nsect = buf[13];
1603
1604	return 0;
1605}
 
 
1606
1607/**
1608 *	atapi_eh_tur - perform ATAPI TEST_UNIT_READY
1609 *	@dev: target ATAPI device
1610 *	@r_sense_key: out parameter for sense_key
1611 *
1612 *	Perform ATAPI TEST_UNIT_READY.
1613 *
1614 *	LOCKING:
1615 *	EH context (may sleep).
1616 *
1617 *	RETURNS:
1618 *	0 on success, AC_ERR_* mask on failure.
1619 */
1620unsigned int atapi_eh_tur(struct ata_device *dev, u8 *r_sense_key)
1621{
1622	u8 cdb[ATAPI_CDB_LEN] = { TEST_UNIT_READY, 0, 0, 0, 0, 0 };
1623	struct ata_taskfile tf;
1624	unsigned int err_mask;
1625
1626	ata_tf_init(dev, &tf);
1627
1628	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1629	tf.command = ATA_CMD_PACKET;
1630	tf.protocol = ATAPI_PROT_NODATA;
 
1631
1632	err_mask = ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
1633	if (err_mask == AC_ERR_DEV)
1634		*r_sense_key = tf.feature >> 4;
1635	return err_mask;
 
 
 
 
 
 
 
 
 
 
 
 
 
1636}
1637
1638/**
1639 *	atapi_eh_request_sense - perform ATAPI REQUEST_SENSE
1640 *	@dev: device to perform REQUEST_SENSE to
1641 *	@sense_buf: result sense data buffer (SCSI_SENSE_BUFFERSIZE bytes long)
1642 *	@dfl_sense_key: default sense key to use
1643 *
1644 *	Perform ATAPI REQUEST_SENSE after the device reported CHECK
1645 *	SENSE.  This function is EH helper.
1646 *
1647 *	LOCKING:
1648 *	Kernel thread context (may sleep).
1649 *
1650 *	RETURNS:
1651 *	0 on success, AC_ERR_* mask on failure
1652 */
1653unsigned int atapi_eh_request_sense(struct ata_device *dev,
1654					   u8 *sense_buf, u8 dfl_sense_key)
1655{
1656	u8 cdb[ATAPI_CDB_LEN] =
1657		{ REQUEST_SENSE, 0, 0, 0, SCSI_SENSE_BUFFERSIZE, 0 };
1658	struct ata_port *ap = dev->link->ap;
1659	struct ata_taskfile tf;
1660
1661	DPRINTK("ATAPI request sense\n");
1662
1663	memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
1664
1665	/* initialize sense_buf with the error register,
1666	 * for the case where they are -not- overwritten
1667	 */
1668	sense_buf[0] = 0x70;
1669	sense_buf[2] = dfl_sense_key;
1670
1671	/* some devices time out if garbage left in tf */
1672	ata_tf_init(dev, &tf);
1673
1674	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1675	tf.command = ATA_CMD_PACKET;
1676
1677	/* is it pointless to prefer PIO for "safety reasons"? */
1678	if (ap->flags & ATA_FLAG_PIO_DMA) {
1679		tf.protocol = ATAPI_PROT_DMA;
1680		tf.feature |= ATAPI_PKT_DMA;
1681	} else {
1682		tf.protocol = ATAPI_PROT_PIO;
1683		tf.lbam = SCSI_SENSE_BUFFERSIZE;
1684		tf.lbah = 0;
1685	}
1686
1687	return ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
1688				 sense_buf, SCSI_SENSE_BUFFERSIZE, 0);
1689}
1690
1691/**
1692 *	ata_eh_analyze_serror - analyze SError for a failed port
1693 *	@link: ATA link to analyze SError for
1694 *
1695 *	Analyze SError if available and further determine cause of
1696 *	failure.
1697 *
1698 *	LOCKING:
1699 *	None.
1700 */
1701static void ata_eh_analyze_serror(struct ata_link *link)
1702{
1703	struct ata_eh_context *ehc = &link->eh_context;
1704	u32 serror = ehc->i.serror;
1705	unsigned int err_mask = 0, action = 0;
1706	u32 hotplug_mask;
1707
1708	if (serror & (SERR_PERSISTENT | SERR_DATA)) {
1709		err_mask |= AC_ERR_ATA_BUS;
1710		action |= ATA_EH_RESET;
1711	}
1712	if (serror & SERR_PROTOCOL) {
1713		err_mask |= AC_ERR_HSM;
1714		action |= ATA_EH_RESET;
1715	}
1716	if (serror & SERR_INTERNAL) {
1717		err_mask |= AC_ERR_SYSTEM;
1718		action |= ATA_EH_RESET;
1719	}
1720
1721	/* Determine whether a hotplug event has occurred.  Both
1722	 * SError.N/X are considered hotplug events for enabled or
1723	 * host links.  For disabled PMP links, only N bit is
1724	 * considered as X bit is left at 1 for link plugging.
1725	 */
1726	if (link->lpm_policy > ATA_LPM_MAX_POWER)
1727		hotplug_mask = 0;	/* hotplug doesn't work w/ LPM */
1728	else if (!(link->flags & ATA_LFLAG_DISABLED) || ata_is_host_link(link))
1729		hotplug_mask = SERR_PHYRDY_CHG | SERR_DEV_XCHG;
1730	else
1731		hotplug_mask = SERR_PHYRDY_CHG;
1732
1733	if (serror & hotplug_mask)
1734		ata_ehi_hotplugged(&ehc->i);
1735
1736	ehc->i.err_mask |= err_mask;
1737	ehc->i.action |= action;
1738}
1739
1740/**
1741 *	ata_eh_analyze_ncq_error - analyze NCQ error
1742 *	@link: ATA link to analyze NCQ error for
1743 *
1744 *	Read log page 10h, determine the offending qc and acquire
1745 *	error status TF.  For NCQ device errors, all LLDDs have to do
1746 *	is setting AC_ERR_DEV in ehi->err_mask.  This function takes
1747 *	care of the rest.
1748 *
1749 *	LOCKING:
1750 *	Kernel thread context (may sleep).
1751 */
1752void ata_eh_analyze_ncq_error(struct ata_link *link)
1753{
1754	struct ata_port *ap = link->ap;
1755	struct ata_eh_context *ehc = &link->eh_context;
1756	struct ata_device *dev = link->device;
1757	struct ata_queued_cmd *qc;
1758	struct ata_taskfile tf;
1759	int tag, rc;
1760
1761	/* if frozen, we can't do much */
1762	if (ap->pflags & ATA_PFLAG_FROZEN)
1763		return;
1764
1765	/* is it NCQ device error? */
1766	if (!link->sactive || !(ehc->i.err_mask & AC_ERR_DEV))
1767		return;
1768
1769	/* has LLDD analyzed already? */
1770	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
1771		qc = __ata_qc_from_tag(ap, tag);
1772
1773		if (!(qc->flags & ATA_QCFLAG_FAILED))
1774			continue;
1775
1776		if (qc->err_mask)
1777			return;
1778	}
1779
1780	/* okay, this error is ours */
1781	memset(&tf, 0, sizeof(tf));
1782	rc = ata_eh_read_log_10h(dev, &tag, &tf);
1783	if (rc) {
1784		ata_link_err(link, "failed to read log page 10h (errno=%d)\n",
1785			     rc);
1786		return;
1787	}
1788
1789	if (!(link->sactive & (1 << tag))) {
1790		ata_link_err(link, "log page 10h reported inactive tag %d\n",
1791			     tag);
1792		return;
1793	}
1794
1795	/* we've got the perpetrator, condemn it */
1796	qc = __ata_qc_from_tag(ap, tag);
1797	memcpy(&qc->result_tf, &tf, sizeof(tf));
1798	qc->result_tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
1799	qc->err_mask |= AC_ERR_DEV | AC_ERR_NCQ;
1800	ehc->i.err_mask &= ~AC_ERR_DEV;
1801}
1802
1803/**
1804 *	ata_eh_analyze_tf - analyze taskfile of a failed qc
1805 *	@qc: qc to analyze
1806 *	@tf: Taskfile registers to analyze
1807 *
1808 *	Analyze taskfile of @qc and further determine cause of
1809 *	failure.  This function also requests ATAPI sense data if
1810 *	available.
1811 *
1812 *	LOCKING:
1813 *	Kernel thread context (may sleep).
1814 *
1815 *	RETURNS:
1816 *	Determined recovery action
1817 */
1818static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc,
1819				      const struct ata_taskfile *tf)
1820{
 
1821	unsigned int tmp, action = 0;
1822	u8 stat = tf->command, err = tf->feature;
1823
1824	if ((stat & (ATA_BUSY | ATA_DRQ | ATA_DRDY)) != ATA_DRDY) {
1825		qc->err_mask |= AC_ERR_HSM;
1826		return ATA_EH_RESET;
1827	}
1828
1829	if (stat & (ATA_ERR | ATA_DF))
1830		qc->err_mask |= AC_ERR_DEV;
1831	else
 
 
 
 
 
 
1832		return 0;
 
1833
1834	switch (qc->dev->class) {
1835	case ATA_DEV_ATA:
1836	case ATA_DEV_ZAC:
 
 
 
 
 
 
 
 
 
 
1837		if (err & ATA_ICRC)
1838			qc->err_mask |= AC_ERR_ATA_BUS;
1839		if (err & (ATA_UNC | ATA_AMNF))
1840			qc->err_mask |= AC_ERR_MEDIA;
1841		if (err & ATA_IDNF)
1842			qc->err_mask |= AC_ERR_INVALID;
1843		break;
1844
1845	case ATA_DEV_ATAPI:
1846		if (!(qc->ap->pflags & ATA_PFLAG_FROZEN)) {
1847			tmp = atapi_eh_request_sense(qc->dev,
1848						qc->scsicmd->sense_buffer,
1849						qc->result_tf.feature >> 4);
1850			if (!tmp) {
1851				/* ATA_QCFLAG_SENSE_VALID is used to
1852				 * tell atapi_qc_complete() that sense
1853				 * data is already valid.
1854				 *
1855				 * TODO: interpret sense data and set
1856				 * appropriate err_mask.
1857				 */
1858				qc->flags |= ATA_QCFLAG_SENSE_VALID;
1859			} else
1860				qc->err_mask |= tmp;
1861		}
1862	}
1863
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1864	if (qc->err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT | AC_ERR_ATA_BUS))
1865		action |= ATA_EH_RESET;
1866
1867	return action;
1868}
1869
1870static int ata_eh_categorize_error(unsigned int eflags, unsigned int err_mask,
1871				   int *xfer_ok)
1872{
1873	int base = 0;
1874
1875	if (!(eflags & ATA_EFLAG_DUBIOUS_XFER))
1876		*xfer_ok = 1;
1877
1878	if (!*xfer_ok)
1879		base = ATA_ECAT_DUBIOUS_NONE;
1880
1881	if (err_mask & AC_ERR_ATA_BUS)
1882		return base + ATA_ECAT_ATA_BUS;
1883
1884	if (err_mask & AC_ERR_TIMEOUT)
1885		return base + ATA_ECAT_TOUT_HSM;
1886
1887	if (eflags & ATA_EFLAG_IS_IO) {
1888		if (err_mask & AC_ERR_HSM)
1889			return base + ATA_ECAT_TOUT_HSM;
1890		if ((err_mask &
1891		     (AC_ERR_DEV|AC_ERR_MEDIA|AC_ERR_INVALID)) == AC_ERR_DEV)
1892			return base + ATA_ECAT_UNK_DEV;
1893	}
1894
1895	return 0;
1896}
1897
1898struct speed_down_verdict_arg {
1899	u64 since;
1900	int xfer_ok;
1901	int nr_errors[ATA_ECAT_NR];
1902};
1903
1904static int speed_down_verdict_cb(struct ata_ering_entry *ent, void *void_arg)
1905{
1906	struct speed_down_verdict_arg *arg = void_arg;
1907	int cat;
1908
1909	if ((ent->eflags & ATA_EFLAG_OLD_ER) || (ent->timestamp < arg->since))
1910		return -1;
1911
1912	cat = ata_eh_categorize_error(ent->eflags, ent->err_mask,
1913				      &arg->xfer_ok);
1914	arg->nr_errors[cat]++;
1915
1916	return 0;
1917}
1918
1919/**
1920 *	ata_eh_speed_down_verdict - Determine speed down verdict
1921 *	@dev: Device of interest
1922 *
1923 *	This function examines error ring of @dev and determines
1924 *	whether NCQ needs to be turned off, transfer speed should be
1925 *	stepped down, or falling back to PIO is necessary.
1926 *
1927 *	ECAT_ATA_BUS	: ATA_BUS error for any command
1928 *
1929 *	ECAT_TOUT_HSM	: TIMEOUT for any command or HSM violation for
1930 *			  IO commands
1931 *
1932 *	ECAT_UNK_DEV	: Unknown DEV error for IO commands
1933 *
1934 *	ECAT_DUBIOUS_*	: Identical to above three but occurred while
1935 *			  data transfer hasn't been verified.
1936 *
1937 *	Verdicts are
1938 *
1939 *	NCQ_OFF		: Turn off NCQ.
1940 *
1941 *	SPEED_DOWN	: Speed down transfer speed but don't fall back
1942 *			  to PIO.
1943 *
1944 *	FALLBACK_TO_PIO	: Fall back to PIO.
1945 *
1946 *	Even if multiple verdicts are returned, only one action is
1947 *	taken per error.  An action triggered by non-DUBIOUS errors
1948 *	clears ering, while one triggered by DUBIOUS_* errors doesn't.
1949 *	This is to expedite speed down decisions right after device is
1950 *	initially configured.
1951 *
1952 *	The followings are speed down rules.  #1 and #2 deal with
1953 *	DUBIOUS errors.
1954 *
1955 *	1. If more than one DUBIOUS_ATA_BUS or DUBIOUS_TOUT_HSM errors
1956 *	   occurred during last 5 mins, SPEED_DOWN and FALLBACK_TO_PIO.
1957 *
1958 *	2. If more than one DUBIOUS_TOUT_HSM or DUBIOUS_UNK_DEV errors
1959 *	   occurred during last 5 mins, NCQ_OFF.
1960 *
1961 *	3. If more than 8 ATA_BUS, TOUT_HSM or UNK_DEV errors
1962 *	   occurred during last 5 mins, FALLBACK_TO_PIO
1963 *
1964 *	4. If more than 3 TOUT_HSM or UNK_DEV errors occurred
1965 *	   during last 10 mins, NCQ_OFF.
1966 *
1967 *	5. If more than 3 ATA_BUS or TOUT_HSM errors, or more than 6
1968 *	   UNK_DEV errors occurred during last 10 mins, SPEED_DOWN.
1969 *
1970 *	LOCKING:
1971 *	Inherited from caller.
1972 *
1973 *	RETURNS:
1974 *	OR of ATA_EH_SPDN_* flags.
1975 */
1976static unsigned int ata_eh_speed_down_verdict(struct ata_device *dev)
1977{
1978	const u64 j5mins = 5LLU * 60 * HZ, j10mins = 10LLU * 60 * HZ;
1979	u64 j64 = get_jiffies_64();
1980	struct speed_down_verdict_arg arg;
1981	unsigned int verdict = 0;
1982
1983	/* scan past 5 mins of error history */
1984	memset(&arg, 0, sizeof(arg));
1985	arg.since = j64 - min(j64, j5mins);
1986	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
1987
1988	if (arg.nr_errors[ATA_ECAT_DUBIOUS_ATA_BUS] +
1989	    arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] > 1)
1990		verdict |= ATA_EH_SPDN_SPEED_DOWN |
1991			ATA_EH_SPDN_FALLBACK_TO_PIO | ATA_EH_SPDN_KEEP_ERRORS;
1992
1993	if (arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] +
1994	    arg.nr_errors[ATA_ECAT_DUBIOUS_UNK_DEV] > 1)
1995		verdict |= ATA_EH_SPDN_NCQ_OFF | ATA_EH_SPDN_KEEP_ERRORS;
1996
1997	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
1998	    arg.nr_errors[ATA_ECAT_TOUT_HSM] +
1999	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
2000		verdict |= ATA_EH_SPDN_FALLBACK_TO_PIO;
2001
2002	/* scan past 10 mins of error history */
2003	memset(&arg, 0, sizeof(arg));
2004	arg.since = j64 - min(j64, j10mins);
2005	ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
2006
2007	if (arg.nr_errors[ATA_ECAT_TOUT_HSM] +
2008	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 3)
2009		verdict |= ATA_EH_SPDN_NCQ_OFF;
2010
2011	if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
2012	    arg.nr_errors[ATA_ECAT_TOUT_HSM] > 3 ||
2013	    arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
2014		verdict |= ATA_EH_SPDN_SPEED_DOWN;
2015
2016	return verdict;
2017}
2018
2019/**
2020 *	ata_eh_speed_down - record error and speed down if necessary
2021 *	@dev: Failed device
2022 *	@eflags: mask of ATA_EFLAG_* flags
2023 *	@err_mask: err_mask of the error
2024 *
2025 *	Record error and examine error history to determine whether
2026 *	adjusting transmission speed is necessary.  It also sets
2027 *	transmission limits appropriately if such adjustment is
2028 *	necessary.
2029 *
2030 *	LOCKING:
2031 *	Kernel thread context (may sleep).
2032 *
2033 *	RETURNS:
2034 *	Determined recovery action.
2035 */
2036static unsigned int ata_eh_speed_down(struct ata_device *dev,
2037				unsigned int eflags, unsigned int err_mask)
2038{
2039	struct ata_link *link = ata_dev_phys_link(dev);
2040	int xfer_ok = 0;
2041	unsigned int verdict;
2042	unsigned int action = 0;
2043
2044	/* don't bother if Cat-0 error */
2045	if (ata_eh_categorize_error(eflags, err_mask, &xfer_ok) == 0)
2046		return 0;
2047
2048	/* record error and determine whether speed down is necessary */
2049	ata_ering_record(&dev->ering, eflags, err_mask);
2050	verdict = ata_eh_speed_down_verdict(dev);
2051
2052	/* turn off NCQ? */
2053	if ((verdict & ATA_EH_SPDN_NCQ_OFF) &&
2054	    (dev->flags & (ATA_DFLAG_PIO | ATA_DFLAG_NCQ |
2055			   ATA_DFLAG_NCQ_OFF)) == ATA_DFLAG_NCQ) {
2056		dev->flags |= ATA_DFLAG_NCQ_OFF;
2057		ata_dev_warn(dev, "NCQ disabled due to excessive errors\n");
2058		goto done;
2059	}
2060
2061	/* speed down? */
2062	if (verdict & ATA_EH_SPDN_SPEED_DOWN) {
2063		/* speed down SATA link speed if possible */
2064		if (sata_down_spd_limit(link, 0) == 0) {
2065			action |= ATA_EH_RESET;
2066			goto done;
2067		}
2068
2069		/* lower transfer mode */
2070		if (dev->spdn_cnt < 2) {
2071			static const int dma_dnxfer_sel[] =
2072				{ ATA_DNXFER_DMA, ATA_DNXFER_40C };
2073			static const int pio_dnxfer_sel[] =
2074				{ ATA_DNXFER_PIO, ATA_DNXFER_FORCE_PIO0 };
2075			int sel;
2076
2077			if (dev->xfer_shift != ATA_SHIFT_PIO)
2078				sel = dma_dnxfer_sel[dev->spdn_cnt];
2079			else
2080				sel = pio_dnxfer_sel[dev->spdn_cnt];
2081
2082			dev->spdn_cnt++;
2083
2084			if (ata_down_xfermask_limit(dev, sel) == 0) {
2085				action |= ATA_EH_RESET;
2086				goto done;
2087			}
2088		}
2089	}
2090
2091	/* Fall back to PIO?  Slowing down to PIO is meaningless for
2092	 * SATA ATA devices.  Consider it only for PATA and SATAPI.
2093	 */
2094	if ((verdict & ATA_EH_SPDN_FALLBACK_TO_PIO) && (dev->spdn_cnt >= 2) &&
2095	    (link->ap->cbl != ATA_CBL_SATA || dev->class == ATA_DEV_ATAPI) &&
2096	    (dev->xfer_shift != ATA_SHIFT_PIO)) {
2097		if (ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO) == 0) {
2098			dev->spdn_cnt = 0;
2099			action |= ATA_EH_RESET;
2100			goto done;
2101		}
2102	}
2103
2104	return 0;
2105 done:
2106	/* device has been slowed down, blow error history */
2107	if (!(verdict & ATA_EH_SPDN_KEEP_ERRORS))
2108		ata_ering_clear(&dev->ering);
2109	return action;
2110}
2111
2112/**
2113 *	ata_eh_worth_retry - analyze error and decide whether to retry
2114 *	@qc: qc to possibly retry
2115 *
2116 *	Look at the cause of the error and decide if a retry
2117 * 	might be useful or not.  We don't want to retry media errors
2118 *	because the drive itself has probably already taken 10-30 seconds
2119 *	doing its own internal retries before reporting the failure.
2120 */
2121static inline int ata_eh_worth_retry(struct ata_queued_cmd *qc)
2122{
2123	if (qc->err_mask & AC_ERR_MEDIA)
2124		return 0;	/* don't retry media errors */
2125	if (qc->flags & ATA_QCFLAG_IO)
2126		return 1;	/* otherwise retry anything from fs stack */
2127	if (qc->err_mask & AC_ERR_INVALID)
2128		return 0;	/* don't retry these */
2129	return qc->err_mask != AC_ERR_DEV;  /* retry if not dev error */
2130}
2131
2132/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2133 *	ata_eh_link_autopsy - analyze error and determine recovery action
2134 *	@link: host link to perform autopsy on
2135 *
2136 *	Analyze why @link failed and determine which recovery actions
2137 *	are needed.  This function also sets more detailed AC_ERR_*
2138 *	values and fills sense data for ATAPI CHECK SENSE.
2139 *
2140 *	LOCKING:
2141 *	Kernel thread context (may sleep).
2142 */
2143static void ata_eh_link_autopsy(struct ata_link *link)
2144{
2145	struct ata_port *ap = link->ap;
2146	struct ata_eh_context *ehc = &link->eh_context;
 
2147	struct ata_device *dev;
2148	unsigned int all_err_mask = 0, eflags = 0;
2149	int tag;
2150	u32 serror;
2151	int rc;
2152
2153	DPRINTK("ENTER\n");
2154
2155	if (ehc->i.flags & ATA_EHI_NO_AUTOPSY)
2156		return;
2157
2158	/* obtain and analyze SError */
2159	rc = sata_scr_read(link, SCR_ERROR, &serror);
2160	if (rc == 0) {
2161		ehc->i.serror |= serror;
2162		ata_eh_analyze_serror(link);
2163	} else if (rc != -EOPNOTSUPP) {
2164		/* SError read failed, force reset and probing */
2165		ehc->i.probe_mask |= ATA_ALL_DEVICES;
2166		ehc->i.action |= ATA_EH_RESET;
2167		ehc->i.err_mask |= AC_ERR_OTHER;
2168	}
2169
2170	/* analyze NCQ failure */
2171	ata_eh_analyze_ncq_error(link);
2172
 
 
 
 
 
 
 
 
2173	/* any real error trumps AC_ERR_OTHER */
2174	if (ehc->i.err_mask & ~AC_ERR_OTHER)
2175		ehc->i.err_mask &= ~AC_ERR_OTHER;
2176
2177	all_err_mask |= ehc->i.err_mask;
2178
2179	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
2180		struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
2181
2182		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2183		    ata_dev_phys_link(qc->dev) != link)
2184			continue;
2185
2186		/* inherit upper level err_mask */
2187		qc->err_mask |= ehc->i.err_mask;
2188
2189		/* analyze TF */
2190		ehc->i.action |= ata_eh_analyze_tf(qc, &qc->result_tf);
2191
2192		/* DEV errors are probably spurious in case of ATA_BUS error */
2193		if (qc->err_mask & AC_ERR_ATA_BUS)
2194			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_MEDIA |
2195					  AC_ERR_INVALID);
2196
2197		/* any real error trumps unknown error */
2198		if (qc->err_mask & ~AC_ERR_OTHER)
2199			qc->err_mask &= ~AC_ERR_OTHER;
2200
2201		/* SENSE_VALID trumps dev/unknown error and revalidation */
 
 
 
 
 
 
2202		if (qc->flags & ATA_QCFLAG_SENSE_VALID)
2203			qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_OTHER);
2204
2205		/* determine whether the command is worth retrying */
2206		if (ata_eh_worth_retry(qc))
2207			qc->flags |= ATA_QCFLAG_RETRY;
2208
2209		/* accumulate error info */
2210		ehc->i.dev = qc->dev;
2211		all_err_mask |= qc->err_mask;
2212		if (qc->flags & ATA_QCFLAG_IO)
2213			eflags |= ATA_EFLAG_IS_IO;
2214		trace_ata_eh_link_autopsy_qc(qc);
 
 
 
 
 
2215	}
2216
 
 
 
 
2217	/* enforce default EH actions */
2218	if (ap->pflags & ATA_PFLAG_FROZEN ||
2219	    all_err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT))
2220		ehc->i.action |= ATA_EH_RESET;
2221	else if (((eflags & ATA_EFLAG_IS_IO) && all_err_mask) ||
2222		 (!(eflags & ATA_EFLAG_IS_IO) && (all_err_mask & ~AC_ERR_DEV)))
2223		ehc->i.action |= ATA_EH_REVALIDATE;
2224
2225	/* If we have offending qcs and the associated failed device,
2226	 * perform per-dev EH action only on the offending device.
2227	 */
2228	if (ehc->i.dev) {
2229		ehc->i.dev_action[ehc->i.dev->devno] |=
2230			ehc->i.action & ATA_EH_PERDEV_MASK;
2231		ehc->i.action &= ~ATA_EH_PERDEV_MASK;
2232	}
2233
2234	/* propagate timeout to host link */
2235	if ((all_err_mask & AC_ERR_TIMEOUT) && !ata_is_host_link(link))
2236		ap->link.eh_context.i.err_mask |= AC_ERR_TIMEOUT;
2237
2238	/* record error and consider speeding down */
2239	dev = ehc->i.dev;
2240	if (!dev && ((ata_link_max_devices(link) == 1 &&
2241		      ata_dev_enabled(link->device))))
2242	    dev = link->device;
2243
2244	if (dev) {
2245		if (dev->flags & ATA_DFLAG_DUBIOUS_XFER)
2246			eflags |= ATA_EFLAG_DUBIOUS_XFER;
2247		ehc->i.action |= ata_eh_speed_down(dev, eflags, all_err_mask);
 
2248	}
2249	trace_ata_eh_link_autopsy(dev, ehc->i.action, all_err_mask);
2250	DPRINTK("EXIT\n");
2251}
2252
2253/**
2254 *	ata_eh_autopsy - analyze error and determine recovery action
2255 *	@ap: host port to perform autopsy on
2256 *
2257 *	Analyze all links of @ap and determine why they failed and
2258 *	which recovery actions are needed.
2259 *
2260 *	LOCKING:
2261 *	Kernel thread context (may sleep).
2262 */
2263void ata_eh_autopsy(struct ata_port *ap)
2264{
2265	struct ata_link *link;
2266
2267	ata_for_each_link(link, ap, EDGE)
2268		ata_eh_link_autopsy(link);
2269
2270	/* Handle the frigging slave link.  Autopsy is done similarly
2271	 * but actions and flags are transferred over to the master
2272	 * link and handled from there.
2273	 */
2274	if (ap->slave_link) {
2275		struct ata_eh_context *mehc = &ap->link.eh_context;
2276		struct ata_eh_context *sehc = &ap->slave_link->eh_context;
2277
2278		/* transfer control flags from master to slave */
2279		sehc->i.flags |= mehc->i.flags & ATA_EHI_TO_SLAVE_MASK;
2280
2281		/* perform autopsy on the slave link */
2282		ata_eh_link_autopsy(ap->slave_link);
2283
2284		/* transfer actions from slave to master and clear slave */
2285		ata_eh_about_to_do(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2286		mehc->i.action		|= sehc->i.action;
2287		mehc->i.dev_action[1]	|= sehc->i.dev_action[1];
2288		mehc->i.flags		|= sehc->i.flags;
2289		ata_eh_done(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
2290	}
2291
2292	/* Autopsy of fanout ports can affect host link autopsy.
2293	 * Perform host link autopsy last.
2294	 */
2295	if (sata_pmp_attached(ap))
2296		ata_eh_link_autopsy(&ap->link);
2297}
2298
2299/**
2300 *	ata_get_cmd_descript - get description for ATA command
2301 *	@command: ATA command code to get description for
2302 *
2303 *	Return a textual description of the given command, or NULL if the
2304 *	command is not known.
2305 *
2306 *	LOCKING:
2307 *	None
2308 */
2309const char *ata_get_cmd_descript(u8 command)
2310{
2311#ifdef CONFIG_ATA_VERBOSE_ERROR
2312	static const struct
2313	{
2314		u8 command;
2315		const char *text;
2316	} cmd_descr[] = {
2317		{ ATA_CMD_DEV_RESET,		"DEVICE RESET" },
2318		{ ATA_CMD_CHK_POWER,		"CHECK POWER MODE" },
2319		{ ATA_CMD_STANDBY,		"STANDBY" },
2320		{ ATA_CMD_IDLE,			"IDLE" },
2321		{ ATA_CMD_EDD,			"EXECUTE DEVICE DIAGNOSTIC" },
2322		{ ATA_CMD_DOWNLOAD_MICRO,	"DOWNLOAD MICROCODE" },
2323		{ ATA_CMD_DOWNLOAD_MICRO_DMA,	"DOWNLOAD MICROCODE DMA" },
2324		{ ATA_CMD_NOP,			"NOP" },
2325		{ ATA_CMD_FLUSH,		"FLUSH CACHE" },
2326		{ ATA_CMD_FLUSH_EXT,		"FLUSH CACHE EXT" },
2327		{ ATA_CMD_ID_ATA,		"IDENTIFY DEVICE" },
2328		{ ATA_CMD_ID_ATAPI,		"IDENTIFY PACKET DEVICE" },
2329		{ ATA_CMD_SERVICE,		"SERVICE" },
2330		{ ATA_CMD_READ,			"READ DMA" },
2331		{ ATA_CMD_READ_EXT,		"READ DMA EXT" },
2332		{ ATA_CMD_READ_QUEUED,		"READ DMA QUEUED" },
2333		{ ATA_CMD_READ_STREAM_EXT,	"READ STREAM EXT" },
2334		{ ATA_CMD_READ_STREAM_DMA_EXT,  "READ STREAM DMA EXT" },
2335		{ ATA_CMD_WRITE,		"WRITE DMA" },
2336		{ ATA_CMD_WRITE_EXT,		"WRITE DMA EXT" },
2337		{ ATA_CMD_WRITE_QUEUED,		"WRITE DMA QUEUED EXT" },
2338		{ ATA_CMD_WRITE_STREAM_EXT,	"WRITE STREAM EXT" },
2339		{ ATA_CMD_WRITE_STREAM_DMA_EXT, "WRITE STREAM DMA EXT" },
2340		{ ATA_CMD_WRITE_FUA_EXT,	"WRITE DMA FUA EXT" },
2341		{ ATA_CMD_WRITE_QUEUED_FUA_EXT, "WRITE DMA QUEUED FUA EXT" },
2342		{ ATA_CMD_FPDMA_READ,		"READ FPDMA QUEUED" },
2343		{ ATA_CMD_FPDMA_WRITE,		"WRITE FPDMA QUEUED" },
 
2344		{ ATA_CMD_FPDMA_SEND,		"SEND FPDMA QUEUED" },
2345		{ ATA_CMD_FPDMA_RECV,		"RECEIVE FPDMA QUEUED" },
2346		{ ATA_CMD_PIO_READ,		"READ SECTOR(S)" },
2347		{ ATA_CMD_PIO_READ_EXT,		"READ SECTOR(S) EXT" },
2348		{ ATA_CMD_PIO_WRITE,		"WRITE SECTOR(S)" },
2349		{ ATA_CMD_PIO_WRITE_EXT,	"WRITE SECTOR(S) EXT" },
2350		{ ATA_CMD_READ_MULTI,		"READ MULTIPLE" },
2351		{ ATA_CMD_READ_MULTI_EXT,	"READ MULTIPLE EXT" },
2352		{ ATA_CMD_WRITE_MULTI,		"WRITE MULTIPLE" },
2353		{ ATA_CMD_WRITE_MULTI_EXT,	"WRITE MULTIPLE EXT" },
2354		{ ATA_CMD_WRITE_MULTI_FUA_EXT,	"WRITE MULTIPLE FUA EXT" },
2355		{ ATA_CMD_SET_FEATURES,		"SET FEATURES" },
2356		{ ATA_CMD_SET_MULTI,		"SET MULTIPLE MODE" },
2357		{ ATA_CMD_VERIFY,		"READ VERIFY SECTOR(S)" },
2358		{ ATA_CMD_VERIFY_EXT,		"READ VERIFY SECTOR(S) EXT" },
2359		{ ATA_CMD_WRITE_UNCORR_EXT,	"WRITE UNCORRECTABLE EXT" },
2360		{ ATA_CMD_STANDBYNOW1,		"STANDBY IMMEDIATE" },
2361		{ ATA_CMD_IDLEIMMEDIATE,	"IDLE IMMEDIATE" },
2362		{ ATA_CMD_SLEEP,		"SLEEP" },
2363		{ ATA_CMD_INIT_DEV_PARAMS,	"INITIALIZE DEVICE PARAMETERS" },
2364		{ ATA_CMD_READ_NATIVE_MAX,	"READ NATIVE MAX ADDRESS" },
2365		{ ATA_CMD_READ_NATIVE_MAX_EXT,	"READ NATIVE MAX ADDRESS EXT" },
2366		{ ATA_CMD_SET_MAX,		"SET MAX ADDRESS" },
2367		{ ATA_CMD_SET_MAX_EXT,		"SET MAX ADDRESS EXT" },
2368		{ ATA_CMD_READ_LOG_EXT,		"READ LOG EXT" },
2369		{ ATA_CMD_WRITE_LOG_EXT,	"WRITE LOG EXT" },
2370		{ ATA_CMD_READ_LOG_DMA_EXT,	"READ LOG DMA EXT" },
2371		{ ATA_CMD_WRITE_LOG_DMA_EXT,	"WRITE LOG DMA EXT" },
2372		{ ATA_CMD_TRUSTED_NONDATA,	"TRUSTED NON-DATA" },
2373		{ ATA_CMD_TRUSTED_RCV,		"TRUSTED RECEIVE" },
2374		{ ATA_CMD_TRUSTED_RCV_DMA,	"TRUSTED RECEIVE DMA" },
2375		{ ATA_CMD_TRUSTED_SND,		"TRUSTED SEND" },
2376		{ ATA_CMD_TRUSTED_SND_DMA,	"TRUSTED SEND DMA" },
2377		{ ATA_CMD_PMP_READ,		"READ BUFFER" },
2378		{ ATA_CMD_PMP_READ_DMA,		"READ BUFFER DMA" },
2379		{ ATA_CMD_PMP_WRITE,		"WRITE BUFFER" },
2380		{ ATA_CMD_PMP_WRITE_DMA,	"WRITE BUFFER DMA" },
2381		{ ATA_CMD_CONF_OVERLAY,		"DEVICE CONFIGURATION OVERLAY" },
2382		{ ATA_CMD_SEC_SET_PASS,		"SECURITY SET PASSWORD" },
2383		{ ATA_CMD_SEC_UNLOCK,		"SECURITY UNLOCK" },
2384		{ ATA_CMD_SEC_ERASE_PREP,	"SECURITY ERASE PREPARE" },
2385		{ ATA_CMD_SEC_ERASE_UNIT,	"SECURITY ERASE UNIT" },
2386		{ ATA_CMD_SEC_FREEZE_LOCK,	"SECURITY FREEZE LOCK" },
2387		{ ATA_CMD_SEC_DISABLE_PASS,	"SECURITY DISABLE PASSWORD" },
2388		{ ATA_CMD_CONFIG_STREAM,	"CONFIGURE STREAM" },
2389		{ ATA_CMD_SMART,		"SMART" },
2390		{ ATA_CMD_MEDIA_LOCK,		"DOOR LOCK" },
2391		{ ATA_CMD_MEDIA_UNLOCK,		"DOOR UNLOCK" },
2392		{ ATA_CMD_DSM,			"DATA SET MANAGEMENT" },
2393		{ ATA_CMD_CHK_MED_CRD_TYP,	"CHECK MEDIA CARD TYPE" },
2394		{ ATA_CMD_CFA_REQ_EXT_ERR,	"CFA REQUEST EXTENDED ERROR" },
2395		{ ATA_CMD_CFA_WRITE_NE,		"CFA WRITE SECTORS WITHOUT ERASE" },
2396		{ ATA_CMD_CFA_TRANS_SECT,	"CFA TRANSLATE SECTOR" },
2397		{ ATA_CMD_CFA_ERASE,		"CFA ERASE SECTORS" },
2398		{ ATA_CMD_CFA_WRITE_MULT_NE,	"CFA WRITE MULTIPLE WITHOUT ERASE" },
2399		{ ATA_CMD_REQ_SENSE_DATA,	"REQUEST SENSE DATA EXT" },
2400		{ ATA_CMD_SANITIZE_DEVICE,	"SANITIZE DEVICE" },
 
 
2401		{ ATA_CMD_READ_LONG,		"READ LONG (with retries)" },
2402		{ ATA_CMD_READ_LONG_ONCE,	"READ LONG (without retries)" },
2403		{ ATA_CMD_WRITE_LONG,		"WRITE LONG (with retries)" },
2404		{ ATA_CMD_WRITE_LONG_ONCE,	"WRITE LONG (without retries)" },
2405		{ ATA_CMD_RESTORE,		"RECALIBRATE" },
2406		{ 0,				NULL } /* terminate list */
2407	};
2408
2409	unsigned int i;
2410	for (i = 0; cmd_descr[i].text; i++)
2411		if (cmd_descr[i].command == command)
2412			return cmd_descr[i].text;
2413#endif
2414
2415	return NULL;
2416}
2417EXPORT_SYMBOL_GPL(ata_get_cmd_descript);
2418
2419/**
2420 *	ata_eh_link_report - report error handling to user
2421 *	@link: ATA link EH is going on
2422 *
2423 *	Report EH to user.
2424 *
2425 *	LOCKING:
2426 *	None.
2427 */
2428static void ata_eh_link_report(struct ata_link *link)
2429{
2430	struct ata_port *ap = link->ap;
2431	struct ata_eh_context *ehc = &link->eh_context;
 
2432	const char *frozen, *desc;
2433	char tries_buf[6] = "";
2434	int tag, nr_failed = 0;
2435
2436	if (ehc->i.flags & ATA_EHI_QUIET)
2437		return;
2438
2439	desc = NULL;
2440	if (ehc->i.desc[0] != '\0')
2441		desc = ehc->i.desc;
2442
2443	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
2444		struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
2445
2446		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2447		    ata_dev_phys_link(qc->dev) != link ||
2448		    ((qc->flags & ATA_QCFLAG_QUIET) &&
2449		     qc->err_mask == AC_ERR_DEV))
2450			continue;
2451		if (qc->flags & ATA_QCFLAG_SENSE_VALID && !qc->err_mask)
2452			continue;
2453
2454		nr_failed++;
2455	}
2456
2457	if (!nr_failed && !ehc->i.err_mask)
2458		return;
2459
2460	frozen = "";
2461	if (ap->pflags & ATA_PFLAG_FROZEN)
2462		frozen = " frozen";
2463
2464	if (ap->eh_tries < ATA_EH_MAX_TRIES)
2465		snprintf(tries_buf, sizeof(tries_buf), " t%d",
2466			 ap->eh_tries);
2467
2468	if (ehc->i.dev) {
2469		ata_dev_err(ehc->i.dev, "exception Emask 0x%x "
2470			    "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2471			    ehc->i.err_mask, link->sactive, ehc->i.serror,
2472			    ehc->i.action, frozen, tries_buf);
2473		if (desc)
2474			ata_dev_err(ehc->i.dev, "%s\n", desc);
2475	} else {
2476		ata_link_err(link, "exception Emask 0x%x "
2477			     "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
2478			     ehc->i.err_mask, link->sactive, ehc->i.serror,
2479			     ehc->i.action, frozen, tries_buf);
2480		if (desc)
2481			ata_link_err(link, "%s\n", desc);
2482	}
2483
2484#ifdef CONFIG_ATA_VERBOSE_ERROR
2485	if (ehc->i.serror)
2486		ata_link_err(link,
2487		  "SError: { %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s}\n",
2488		  ehc->i.serror & SERR_DATA_RECOVERED ? "RecovData " : "",
2489		  ehc->i.serror & SERR_COMM_RECOVERED ? "RecovComm " : "",
2490		  ehc->i.serror & SERR_DATA ? "UnrecovData " : "",
2491		  ehc->i.serror & SERR_PERSISTENT ? "Persist " : "",
2492		  ehc->i.serror & SERR_PROTOCOL ? "Proto " : "",
2493		  ehc->i.serror & SERR_INTERNAL ? "HostInt " : "",
2494		  ehc->i.serror & SERR_PHYRDY_CHG ? "PHYRdyChg " : "",
2495		  ehc->i.serror & SERR_PHY_INT_ERR ? "PHYInt " : "",
2496		  ehc->i.serror & SERR_COMM_WAKE ? "CommWake " : "",
2497		  ehc->i.serror & SERR_10B_8B_ERR ? "10B8B " : "",
2498		  ehc->i.serror & SERR_DISPARITY ? "Dispar " : "",
2499		  ehc->i.serror & SERR_CRC ? "BadCRC " : "",
2500		  ehc->i.serror & SERR_HANDSHAKE ? "Handshk " : "",
2501		  ehc->i.serror & SERR_LINK_SEQ_ERR ? "LinkSeq " : "",
2502		  ehc->i.serror & SERR_TRANS_ST_ERROR ? "TrStaTrns " : "",
2503		  ehc->i.serror & SERR_UNRECOG_FIS ? "UnrecFIS " : "",
2504		  ehc->i.serror & SERR_DEV_XCHG ? "DevExch " : "");
2505#endif
2506
2507	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
2508		struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
2509		struct ata_taskfile *cmd = &qc->tf, *res = &qc->result_tf;
2510		char data_buf[20] = "";
2511		char cdb_buf[70] = "";
2512
2513		if (!(qc->flags & ATA_QCFLAG_FAILED) ||
2514		    ata_dev_phys_link(qc->dev) != link || !qc->err_mask)
2515			continue;
2516
2517		if (qc->dma_dir != DMA_NONE) {
2518			static const char *dma_str[] = {
2519				[DMA_BIDIRECTIONAL]	= "bidi",
2520				[DMA_TO_DEVICE]		= "out",
2521				[DMA_FROM_DEVICE]	= "in",
2522			};
2523			static const char *prot_str[] = {
2524				[ATA_PROT_PIO]		= "pio",
2525				[ATA_PROT_DMA]		= "dma",
2526				[ATA_PROT_NCQ]		= "ncq",
2527				[ATAPI_PROT_PIO]	= "pio",
2528				[ATAPI_PROT_DMA]	= "dma",
2529			};
2530
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2531			snprintf(data_buf, sizeof(data_buf), " %s %u %s",
2532				 prot_str[qc->tf.protocol], qc->nbytes,
2533				 dma_str[qc->dma_dir]);
2534		}
2535
2536		if (ata_is_atapi(qc->tf.protocol)) {
2537			const u8 *cdb = qc->cdb;
2538			size_t cdb_len = qc->dev->cdb_len;
2539
2540			if (qc->scsicmd) {
2541				cdb = qc->scsicmd->cmnd;
2542				cdb_len = qc->scsicmd->cmd_len;
2543			}
2544			__scsi_format_command(cdb_buf, sizeof(cdb_buf),
2545					      cdb, cdb_len);
2546		} else {
2547			const char *descr = ata_get_cmd_descript(cmd->command);
2548			if (descr)
2549				ata_dev_err(qc->dev, "failed command: %s\n",
2550					    descr);
2551		}
2552
2553		ata_dev_err(qc->dev,
2554			"cmd %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2555			"tag %d%s\n         %s"
2556			"res %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
2557			"Emask 0x%x (%s)%s\n",
2558			cmd->command, cmd->feature, cmd->nsect,
2559			cmd->lbal, cmd->lbam, cmd->lbah,
2560			cmd->hob_feature, cmd->hob_nsect,
2561			cmd->hob_lbal, cmd->hob_lbam, cmd->hob_lbah,
2562			cmd->device, qc->tag, data_buf, cdb_buf,
2563			res->command, res->feature, res->nsect,
2564			res->lbal, res->lbam, res->lbah,
2565			res->hob_feature, res->hob_nsect,
2566			res->hob_lbal, res->hob_lbam, res->hob_lbah,
2567			res->device, qc->err_mask, ata_err_string(qc->err_mask),
2568			qc->err_mask & AC_ERR_NCQ ? " <F>" : "");
2569
2570#ifdef CONFIG_ATA_VERBOSE_ERROR
2571		if (res->command & (ATA_BUSY | ATA_DRDY | ATA_DF | ATA_DRQ |
2572				    ATA_ERR)) {
2573			if (res->command & ATA_BUSY)
2574				ata_dev_err(qc->dev, "status: { Busy }\n");
2575			else
2576				ata_dev_err(qc->dev, "status: { %s%s%s%s}\n",
2577				  res->command & ATA_DRDY ? "DRDY " : "",
2578				  res->command & ATA_DF ? "DF " : "",
2579				  res->command & ATA_DRQ ? "DRQ " : "",
2580				  res->command & ATA_ERR ? "ERR " : "");
 
2581		}
2582
2583		if (cmd->command != ATA_CMD_PACKET &&
2584		    (res->feature & (ATA_ICRC | ATA_UNC | ATA_AMNF |
2585				     ATA_IDNF | ATA_ABORTED)))
2586			ata_dev_err(qc->dev, "error: { %s%s%s%s%s}\n",
2587			  res->feature & ATA_ICRC ? "ICRC " : "",
2588			  res->feature & ATA_UNC ? "UNC " : "",
2589			  res->feature & ATA_AMNF ? "AMNF " : "",
2590			  res->feature & ATA_IDNF ? "IDNF " : "",
2591			  res->feature & ATA_ABORTED ? "ABRT " : "");
2592#endif
2593	}
2594}
2595
2596/**
2597 *	ata_eh_report - report error handling to user
2598 *	@ap: ATA port to report EH about
2599 *
2600 *	Report EH to user.
2601 *
2602 *	LOCKING:
2603 *	None.
2604 */
2605void ata_eh_report(struct ata_port *ap)
2606{
2607	struct ata_link *link;
2608
2609	ata_for_each_link(link, ap, HOST_FIRST)
2610		ata_eh_link_report(link);
2611}
2612
2613static int ata_do_reset(struct ata_link *link, ata_reset_fn_t reset,
2614			unsigned int *classes, unsigned long deadline,
2615			bool clear_classes)
2616{
2617	struct ata_device *dev;
2618
2619	if (clear_classes)
2620		ata_for_each_dev(dev, link, ALL)
2621			classes[dev->devno] = ATA_DEV_UNKNOWN;
2622
2623	return reset(link, classes, deadline);
2624}
2625
2626static int ata_eh_followup_srst_needed(struct ata_link *link, int rc)
2627{
2628	if ((link->flags & ATA_LFLAG_NO_SRST) || ata_link_offline(link))
2629		return 0;
2630	if (rc == -EAGAIN)
2631		return 1;
2632	if (sata_pmp_supported(link->ap) && ata_is_host_link(link))
2633		return 1;
2634	return 0;
2635}
2636
2637int ata_eh_reset(struct ata_link *link, int classify,
2638		 ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
2639		 ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
2640{
2641	struct ata_port *ap = link->ap;
2642	struct ata_link *slave = ap->slave_link;
2643	struct ata_eh_context *ehc = &link->eh_context;
2644	struct ata_eh_context *sehc = slave ? &slave->eh_context : NULL;
2645	unsigned int *classes = ehc->classes;
2646	unsigned int lflags = link->flags;
2647	int verbose = !(ehc->i.flags & ATA_EHI_QUIET);
2648	int max_tries = 0, try = 0;
2649	struct ata_link *failed_link;
2650	struct ata_device *dev;
2651	unsigned long deadline, now;
2652	ata_reset_fn_t reset;
2653	unsigned long flags;
2654	u32 sstatus;
2655	int nr_unknown, rc;
2656
2657	/*
2658	 * Prepare to reset
2659	 */
2660	while (ata_eh_reset_timeouts[max_tries] != ULONG_MAX)
2661		max_tries++;
2662	if (link->flags & ATA_LFLAG_RST_ONCE)
2663		max_tries = 1;
2664	if (link->flags & ATA_LFLAG_NO_HRST)
2665		hardreset = NULL;
2666	if (link->flags & ATA_LFLAG_NO_SRST)
2667		softreset = NULL;
2668
2669	/* make sure each reset attempt is at least COOL_DOWN apart */
2670	if (ehc->i.flags & ATA_EHI_DID_RESET) {
2671		now = jiffies;
2672		WARN_ON(time_after(ehc->last_reset, now));
2673		deadline = ata_deadline(ehc->last_reset,
2674					ATA_EH_RESET_COOL_DOWN);
2675		if (time_before(now, deadline))
2676			schedule_timeout_uninterruptible(deadline - now);
2677	}
2678
2679	spin_lock_irqsave(ap->lock, flags);
2680	ap->pflags |= ATA_PFLAG_RESETTING;
2681	spin_unlock_irqrestore(ap->lock, flags);
2682
2683	ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
2684
2685	ata_for_each_dev(dev, link, ALL) {
2686		/* If we issue an SRST then an ATA drive (not ATAPI)
2687		 * may change configuration and be in PIO0 timing. If
2688		 * we do a hard reset (or are coming from power on)
2689		 * this is true for ATA or ATAPI. Until we've set a
2690		 * suitable controller mode we should not touch the
2691		 * bus as we may be talking too fast.
2692		 */
2693		dev->pio_mode = XFER_PIO_0;
2694		dev->dma_mode = 0xff;
2695
2696		/* If the controller has a pio mode setup function
2697		 * then use it to set the chipset to rights. Don't
2698		 * touch the DMA setup as that will be dealt with when
2699		 * configuring devices.
2700		 */
2701		if (ap->ops->set_piomode)
2702			ap->ops->set_piomode(ap, dev);
2703	}
2704
2705	/* prefer hardreset */
2706	reset = NULL;
2707	ehc->i.action &= ~ATA_EH_RESET;
2708	if (hardreset) {
2709		reset = hardreset;
2710		ehc->i.action |= ATA_EH_HARDRESET;
2711	} else if (softreset) {
2712		reset = softreset;
2713		ehc->i.action |= ATA_EH_SOFTRESET;
2714	}
2715
2716	if (prereset) {
2717		unsigned long deadline = ata_deadline(jiffies,
2718						      ATA_EH_PRERESET_TIMEOUT);
2719
2720		if (slave) {
2721			sehc->i.action &= ~ATA_EH_RESET;
2722			sehc->i.action |= ehc->i.action;
2723		}
2724
2725		rc = prereset(link, deadline);
2726
2727		/* If present, do prereset on slave link too.  Reset
2728		 * is skipped iff both master and slave links report
2729		 * -ENOENT or clear ATA_EH_RESET.
2730		 */
2731		if (slave && (rc == 0 || rc == -ENOENT)) {
2732			int tmp;
2733
2734			tmp = prereset(slave, deadline);
2735			if (tmp != -ENOENT)
2736				rc = tmp;
2737
2738			ehc->i.action |= sehc->i.action;
2739		}
2740
2741		if (rc) {
2742			if (rc == -ENOENT) {
2743				ata_link_dbg(link, "port disabled--ignoring\n");
2744				ehc->i.action &= ~ATA_EH_RESET;
2745
2746				ata_for_each_dev(dev, link, ALL)
2747					classes[dev->devno] = ATA_DEV_NONE;
2748
2749				rc = 0;
2750			} else
2751				ata_link_err(link,
2752					     "prereset failed (errno=%d)\n",
2753					     rc);
2754			goto out;
2755		}
2756
2757		/* prereset() might have cleared ATA_EH_RESET.  If so,
2758		 * bang classes, thaw and return.
2759		 */
2760		if (reset && !(ehc->i.action & ATA_EH_RESET)) {
2761			ata_for_each_dev(dev, link, ALL)
2762				classes[dev->devno] = ATA_DEV_NONE;
2763			if ((ap->pflags & ATA_PFLAG_FROZEN) &&
2764			    ata_is_host_link(link))
2765				ata_eh_thaw_port(ap);
2766			rc = 0;
2767			goto out;
2768		}
2769	}
2770
2771 retry:
2772	/*
2773	 * Perform reset
2774	 */
2775	if (ata_is_host_link(link))
2776		ata_eh_freeze_port(ap);
2777
2778	deadline = ata_deadline(jiffies, ata_eh_reset_timeouts[try++]);
2779
2780	if (reset) {
2781		if (verbose)
2782			ata_link_info(link, "%s resetting link\n",
2783				      reset == softreset ? "soft" : "hard");
2784
2785		/* mark that this EH session started with reset */
2786		ehc->last_reset = jiffies;
2787		if (reset == hardreset)
2788			ehc->i.flags |= ATA_EHI_DID_HARDRESET;
2789		else
 
2790			ehc->i.flags |= ATA_EHI_DID_SOFTRESET;
 
 
2791
2792		rc = ata_do_reset(link, reset, classes, deadline, true);
 
 
 
 
2793		if (rc && rc != -EAGAIN) {
2794			failed_link = link;
2795			goto fail;
2796		}
2797
2798		/* hardreset slave link if existent */
2799		if (slave && reset == hardreset) {
2800			int tmp;
2801
2802			if (verbose)
2803				ata_link_info(slave, "hard resetting link\n");
2804
2805			ata_eh_about_to_do(slave, NULL, ATA_EH_RESET);
 
 
2806			tmp = ata_do_reset(slave, reset, classes, deadline,
2807					   false);
 
2808			switch (tmp) {
2809			case -EAGAIN:
2810				rc = -EAGAIN;
 
2811			case 0:
2812				break;
2813			default:
2814				failed_link = slave;
2815				rc = tmp;
2816				goto fail;
2817			}
2818		}
2819
2820		/* perform follow-up SRST if necessary */
2821		if (reset == hardreset &&
2822		    ata_eh_followup_srst_needed(link, rc)) {
2823			reset = softreset;
2824
2825			if (!reset) {
2826				ata_link_err(link,
2827	     "follow-up softreset required but no softreset available\n");
2828				failed_link = link;
2829				rc = -EINVAL;
2830				goto fail;
2831			}
2832
2833			ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
 
2834			rc = ata_do_reset(link, reset, classes, deadline, true);
 
2835			if (rc) {
2836				failed_link = link;
2837				goto fail;
2838			}
2839		}
2840	} else {
2841		if (verbose)
2842			ata_link_info(link,
2843	"no reset method available, skipping reset\n");
2844		if (!(lflags & ATA_LFLAG_ASSUME_CLASS))
2845			lflags |= ATA_LFLAG_ASSUME_ATA;
2846	}
2847
2848	/*
2849	 * Post-reset processing
2850	 */
2851	ata_for_each_dev(dev, link, ALL) {
2852		/* After the reset, the device state is PIO 0 and the
2853		 * controller state is undefined.  Reset also wakes up
2854		 * drives from sleeping mode.
2855		 */
2856		dev->pio_mode = XFER_PIO_0;
2857		dev->flags &= ~ATA_DFLAG_SLEEPING;
2858
2859		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
2860			continue;
2861
2862		/* apply class override */
2863		if (lflags & ATA_LFLAG_ASSUME_ATA)
2864			classes[dev->devno] = ATA_DEV_ATA;
2865		else if (lflags & ATA_LFLAG_ASSUME_SEMB)
2866			classes[dev->devno] = ATA_DEV_SEMB_UNSUP;
2867	}
2868
2869	/* record current link speed */
2870	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0)
2871		link->sata_spd = (sstatus >> 4) & 0xf;
2872	if (slave && sata_scr_read(slave, SCR_STATUS, &sstatus) == 0)
2873		slave->sata_spd = (sstatus >> 4) & 0xf;
2874
2875	/* thaw the port */
2876	if (ata_is_host_link(link))
2877		ata_eh_thaw_port(ap);
2878
2879	/* postreset() should clear hardware SError.  Although SError
2880	 * is cleared during link resume, clearing SError here is
2881	 * necessary as some PHYs raise hotplug events after SRST.
2882	 * This introduces race condition where hotplug occurs between
2883	 * reset and here.  This race is mediated by cross checking
2884	 * link onlineness and classification result later.
2885	 */
2886	if (postreset) {
2887		postreset(link, classes);
2888		if (slave)
 
2889			postreset(slave, classes);
 
 
2890	}
2891
2892	/*
2893	 * Some controllers can't be frozen very well and may set spurious
2894	 * error conditions during reset.  Clear accumulated error
2895	 * information and re-thaw the port if frozen.  As reset is the
2896	 * final recovery action and we cross check link onlineness against
2897	 * device classification later, no hotplug event is lost by this.
2898	 */
2899	spin_lock_irqsave(link->ap->lock, flags);
2900	memset(&link->eh_info, 0, sizeof(link->eh_info));
2901	if (slave)
2902		memset(&slave->eh_info, 0, sizeof(link->eh_info));
2903	ap->pflags &= ~ATA_PFLAG_EH_PENDING;
2904	spin_unlock_irqrestore(link->ap->lock, flags);
2905
2906	if (ap->pflags & ATA_PFLAG_FROZEN)
2907		ata_eh_thaw_port(ap);
2908
2909	/*
2910	 * Make sure onlineness and classification result correspond.
2911	 * Hotplug could have happened during reset and some
2912	 * controllers fail to wait while a drive is spinning up after
2913	 * being hotplugged causing misdetection.  By cross checking
2914	 * link on/offlineness and classification result, those
2915	 * conditions can be reliably detected and retried.
2916	 */
2917	nr_unknown = 0;
2918	ata_for_each_dev(dev, link, ALL) {
2919		if (ata_phys_link_online(ata_dev_phys_link(dev))) {
2920			if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2921				ata_dev_dbg(dev, "link online but device misclassified\n");
2922				classes[dev->devno] = ATA_DEV_NONE;
2923				nr_unknown++;
2924			}
2925		} else if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
2926			if (ata_class_enabled(classes[dev->devno]))
2927				ata_dev_dbg(dev,
2928					    "link offline, clearing class %d to NONE\n",
2929					    classes[dev->devno]);
2930			classes[dev->devno] = ATA_DEV_NONE;
2931		} else if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
2932			ata_dev_dbg(dev,
2933				    "link status unknown, clearing UNKNOWN to NONE\n");
2934			classes[dev->devno] = ATA_DEV_NONE;
2935		}
2936	}
2937
2938	if (classify && nr_unknown) {
2939		if (try < max_tries) {
2940			ata_link_warn(link,
2941				      "link online but %d devices misclassified, retrying\n",
2942				      nr_unknown);
2943			failed_link = link;
2944			rc = -EAGAIN;
2945			goto fail;
2946		}
2947		ata_link_warn(link,
2948			      "link online but %d devices misclassified, "
2949			      "device detection might fail\n", nr_unknown);
2950	}
2951
2952	/* reset successful, schedule revalidation */
2953	ata_eh_done(link, NULL, ATA_EH_RESET);
2954	if (slave)
2955		ata_eh_done(slave, NULL, ATA_EH_RESET);
2956	ehc->last_reset = jiffies;		/* update to completion time */
2957	ehc->i.action |= ATA_EH_REVALIDATE;
2958	link->lpm_policy = ATA_LPM_UNKNOWN;	/* reset LPM state */
2959
2960	rc = 0;
2961 out:
2962	/* clear hotplug flag */
2963	ehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2964	if (slave)
2965		sehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
2966
2967	spin_lock_irqsave(ap->lock, flags);
2968	ap->pflags &= ~ATA_PFLAG_RESETTING;
2969	spin_unlock_irqrestore(ap->lock, flags);
2970
2971	return rc;
2972
2973 fail:
2974	/* if SCR isn't accessible on a fan-out port, PMP needs to be reset */
2975	if (!ata_is_host_link(link) &&
2976	    sata_scr_read(link, SCR_STATUS, &sstatus))
2977		rc = -ERESTART;
2978
2979	if (try >= max_tries) {
2980		/*
2981		 * Thaw host port even if reset failed, so that the port
2982		 * can be retried on the next phy event.  This risks
2983		 * repeated EH runs but seems to be a better tradeoff than
2984		 * shutting down a port after a botched hotplug attempt.
2985		 */
2986		if (ata_is_host_link(link))
2987			ata_eh_thaw_port(ap);
 
 
2988		goto out;
2989	}
2990
2991	now = jiffies;
2992	if (time_before(now, deadline)) {
2993		unsigned long delta = deadline - now;
2994
2995		ata_link_warn(failed_link,
2996			"reset failed (errno=%d), retrying in %u secs\n",
2997			rc, DIV_ROUND_UP(jiffies_to_msecs(delta), 1000));
2998
2999		ata_eh_release(ap);
3000		while (delta)
3001			delta = schedule_timeout_uninterruptible(delta);
3002		ata_eh_acquire(ap);
3003	}
3004
3005	/*
3006	 * While disks spinup behind PMP, some controllers fail sending SRST.
3007	 * They need to be reset - as well as the PMP - before retrying.
3008	 */
3009	if (rc == -ERESTART) {
3010		if (ata_is_host_link(link))
3011			ata_eh_thaw_port(ap);
3012		goto out;
3013	}
3014
3015	if (try == max_tries - 1) {
3016		sata_down_spd_limit(link, 0);
3017		if (slave)
3018			sata_down_spd_limit(slave, 0);
3019	} else if (rc == -EPIPE)
3020		sata_down_spd_limit(failed_link, 0);
3021
3022	if (hardreset)
3023		reset = hardreset;
3024	goto retry;
3025}
3026
3027static inline void ata_eh_pull_park_action(struct ata_port *ap)
3028{
3029	struct ata_link *link;
3030	struct ata_device *dev;
3031	unsigned long flags;
3032
3033	/*
3034	 * This function can be thought of as an extended version of
3035	 * ata_eh_about_to_do() specially crafted to accommodate the
3036	 * requirements of ATA_EH_PARK handling. Since the EH thread
3037	 * does not leave the do {} while () loop in ata_eh_recover as
3038	 * long as the timeout for a park request to *one* device on
3039	 * the port has not expired, and since we still want to pick
3040	 * up park requests to other devices on the same port or
3041	 * timeout updates for the same device, we have to pull
3042	 * ATA_EH_PARK actions from eh_info into eh_context.i
3043	 * ourselves at the beginning of each pass over the loop.
3044	 *
3045	 * Additionally, all write accesses to &ap->park_req_pending
3046	 * through reinit_completion() (see below) or complete_all()
3047	 * (see ata_scsi_park_store()) are protected by the host lock.
3048	 * As a result we have that park_req_pending.done is zero on
3049	 * exit from this function, i.e. when ATA_EH_PARK actions for
3050	 * *all* devices on port ap have been pulled into the
3051	 * respective eh_context structs. If, and only if,
3052	 * park_req_pending.done is non-zero by the time we reach
3053	 * wait_for_completion_timeout(), another ATA_EH_PARK action
3054	 * has been scheduled for at least one of the devices on port
3055	 * ap and we have to cycle over the do {} while () loop in
3056	 * ata_eh_recover() again.
3057	 */
3058
3059	spin_lock_irqsave(ap->lock, flags);
3060	reinit_completion(&ap->park_req_pending);
3061	ata_for_each_link(link, ap, EDGE) {
3062		ata_for_each_dev(dev, link, ALL) {
3063			struct ata_eh_info *ehi = &link->eh_info;
3064
3065			link->eh_context.i.dev_action[dev->devno] |=
3066				ehi->dev_action[dev->devno] & ATA_EH_PARK;
3067			ata_eh_clear_action(link, dev, ehi, ATA_EH_PARK);
3068		}
3069	}
3070	spin_unlock_irqrestore(ap->lock, flags);
3071}
3072
3073static void ata_eh_park_issue_cmd(struct ata_device *dev, int park)
3074{
3075	struct ata_eh_context *ehc = &dev->link->eh_context;
3076	struct ata_taskfile tf;
3077	unsigned int err_mask;
3078
3079	ata_tf_init(dev, &tf);
3080	if (park) {
3081		ehc->unloaded_mask |= 1 << dev->devno;
3082		tf.command = ATA_CMD_IDLEIMMEDIATE;
3083		tf.feature = 0x44;
3084		tf.lbal = 0x4c;
3085		tf.lbam = 0x4e;
3086		tf.lbah = 0x55;
3087	} else {
3088		ehc->unloaded_mask &= ~(1 << dev->devno);
3089		tf.command = ATA_CMD_CHK_POWER;
3090	}
3091
3092	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
3093	tf.protocol |= ATA_PROT_NODATA;
3094	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
3095	if (park && (err_mask || tf.lbal != 0xc4)) {
3096		ata_dev_err(dev, "head unload failed!\n");
3097		ehc->unloaded_mask &= ~(1 << dev->devno);
3098	}
3099}
3100
3101static int ata_eh_revalidate_and_attach(struct ata_link *link,
3102					struct ata_device **r_failed_dev)
3103{
3104	struct ata_port *ap = link->ap;
3105	struct ata_eh_context *ehc = &link->eh_context;
3106	struct ata_device *dev;
3107	unsigned int new_mask = 0;
3108	unsigned long flags;
3109	int rc = 0;
3110
3111	DPRINTK("ENTER\n");
3112
3113	/* For PATA drive side cable detection to work, IDENTIFY must
3114	 * be done backwards such that PDIAG- is released by the slave
3115	 * device before the master device is identified.
3116	 */
3117	ata_for_each_dev(dev, link, ALL_REVERSE) {
3118		unsigned int action = ata_eh_dev_action(dev);
3119		unsigned int readid_flags = 0;
3120
3121		if (ehc->i.flags & ATA_EHI_DID_RESET)
3122			readid_flags |= ATA_READID_POSTRESET;
3123
3124		if ((action & ATA_EH_REVALIDATE) && ata_dev_enabled(dev)) {
3125			WARN_ON(dev->class == ATA_DEV_PMP);
3126
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3127			if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
3128				rc = -EIO;
3129				goto err;
3130			}
3131
3132			ata_eh_about_to_do(link, dev, ATA_EH_REVALIDATE);
3133			rc = ata_dev_revalidate(dev, ehc->classes[dev->devno],
3134						readid_flags);
3135			if (rc)
3136				goto err;
3137
3138			ata_eh_done(link, dev, ATA_EH_REVALIDATE);
3139
3140			/* Configuration may have changed, reconfigure
3141			 * transfer mode.
3142			 */
3143			ehc->i.flags |= ATA_EHI_SETMODE;
3144
3145			/* schedule the scsi_rescan_device() here */
3146			schedule_work(&(ap->scsi_rescan_task));
3147		} else if (dev->class == ATA_DEV_UNKNOWN &&
3148			   ehc->tries[dev->devno] &&
3149			   ata_class_enabled(ehc->classes[dev->devno])) {
3150			/* Temporarily set dev->class, it will be
3151			 * permanently set once all configurations are
3152			 * complete.  This is necessary because new
3153			 * device configuration is done in two
3154			 * separate loops.
3155			 */
3156			dev->class = ehc->classes[dev->devno];
3157
3158			if (dev->class == ATA_DEV_PMP)
3159				rc = sata_pmp_attach(dev);
3160			else
3161				rc = ata_dev_read_id(dev, &dev->class,
3162						     readid_flags, dev->id);
3163
3164			/* read_id might have changed class, store and reset */
3165			ehc->classes[dev->devno] = dev->class;
3166			dev->class = ATA_DEV_UNKNOWN;
3167
3168			switch (rc) {
3169			case 0:
3170				/* clear error info accumulated during probe */
3171				ata_ering_clear(&dev->ering);
3172				new_mask |= 1 << dev->devno;
3173				break;
3174			case -ENOENT:
3175				/* IDENTIFY was issued to non-existent
3176				 * device.  No need to reset.  Just
3177				 * thaw and ignore the device.
3178				 */
3179				ata_eh_thaw_port(ap);
3180				break;
3181			default:
3182				goto err;
3183			}
3184		}
3185	}
3186
3187	/* PDIAG- should have been released, ask cable type if post-reset */
3188	if ((ehc->i.flags & ATA_EHI_DID_RESET) && ata_is_host_link(link)) {
3189		if (ap->ops->cable_detect)
3190			ap->cbl = ap->ops->cable_detect(ap);
3191		ata_force_cbl(ap);
3192	}
3193
3194	/* Configure new devices forward such that user doesn't see
3195	 * device detection messages backwards.
3196	 */
3197	ata_for_each_dev(dev, link, ALL) {
3198		if (!(new_mask & (1 << dev->devno)))
3199			continue;
3200
3201		dev->class = ehc->classes[dev->devno];
3202
3203		if (dev->class == ATA_DEV_PMP)
3204			continue;
3205
3206		ehc->i.flags |= ATA_EHI_PRINTINFO;
3207		rc = ata_dev_configure(dev);
3208		ehc->i.flags &= ~ATA_EHI_PRINTINFO;
3209		if (rc) {
3210			dev->class = ATA_DEV_UNKNOWN;
3211			goto err;
3212		}
3213
3214		spin_lock_irqsave(ap->lock, flags);
3215		ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
3216		spin_unlock_irqrestore(ap->lock, flags);
3217
3218		/* new device discovered, configure xfermode */
3219		ehc->i.flags |= ATA_EHI_SETMODE;
3220	}
3221
3222	return 0;
3223
3224 err:
3225	*r_failed_dev = dev;
3226	DPRINTK("EXIT rc=%d\n", rc);
3227	return rc;
3228}
3229
3230/**
3231 *	ata_set_mode - Program timings and issue SET FEATURES - XFER
3232 *	@link: link on which timings will be programmed
3233 *	@r_failed_dev: out parameter for failed device
3234 *
3235 *	Set ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3236 *	ata_set_mode() fails, pointer to the failing device is
3237 *	returned in @r_failed_dev.
3238 *
3239 *	LOCKING:
3240 *	PCI/etc. bus probe sem.
3241 *
3242 *	RETURNS:
3243 *	0 on success, negative errno otherwise
3244 */
3245int ata_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3246{
3247	struct ata_port *ap = link->ap;
3248	struct ata_device *dev;
3249	int rc;
3250
3251	/* if data transfer is verified, clear DUBIOUS_XFER on ering top */
3252	ata_for_each_dev(dev, link, ENABLED) {
3253		if (!(dev->flags & ATA_DFLAG_DUBIOUS_XFER)) {
3254			struct ata_ering_entry *ent;
3255
3256			ent = ata_ering_top(&dev->ering);
3257			if (ent)
3258				ent->eflags &= ~ATA_EFLAG_DUBIOUS_XFER;
3259		}
3260	}
3261
3262	/* has private set_mode? */
3263	if (ap->ops->set_mode)
3264		rc = ap->ops->set_mode(link, r_failed_dev);
3265	else
3266		rc = ata_do_set_mode(link, r_failed_dev);
3267
3268	/* if transfer mode has changed, set DUBIOUS_XFER on device */
3269	ata_for_each_dev(dev, link, ENABLED) {
3270		struct ata_eh_context *ehc = &link->eh_context;
3271		u8 saved_xfer_mode = ehc->saved_xfer_mode[dev->devno];
3272		u8 saved_ncq = !!(ehc->saved_ncq_enabled & (1 << dev->devno));
3273
3274		if (dev->xfer_mode != saved_xfer_mode ||
3275		    ata_ncq_enabled(dev) != saved_ncq)
3276			dev->flags |= ATA_DFLAG_DUBIOUS_XFER;
3277	}
3278
3279	return rc;
3280}
3281
3282/**
3283 *	atapi_eh_clear_ua - Clear ATAPI UNIT ATTENTION after reset
3284 *	@dev: ATAPI device to clear UA for
3285 *
3286 *	Resets and other operations can make an ATAPI device raise
3287 *	UNIT ATTENTION which causes the next operation to fail.  This
3288 *	function clears UA.
3289 *
3290 *	LOCKING:
3291 *	EH context (may sleep).
3292 *
3293 *	RETURNS:
3294 *	0 on success, -errno on failure.
3295 */
3296static int atapi_eh_clear_ua(struct ata_device *dev)
3297{
3298	int i;
3299
3300	for (i = 0; i < ATA_EH_UA_TRIES; i++) {
3301		u8 *sense_buffer = dev->link->ap->sector_buf;
3302		u8 sense_key = 0;
3303		unsigned int err_mask;
3304
3305		err_mask = atapi_eh_tur(dev, &sense_key);
3306		if (err_mask != 0 && err_mask != AC_ERR_DEV) {
3307			ata_dev_warn(dev,
3308				     "TEST_UNIT_READY failed (err_mask=0x%x)\n",
3309				     err_mask);
3310			return -EIO;
3311		}
3312
3313		if (!err_mask || sense_key != UNIT_ATTENTION)
3314			return 0;
3315
3316		err_mask = atapi_eh_request_sense(dev, sense_buffer, sense_key);
3317		if (err_mask) {
3318			ata_dev_warn(dev, "failed to clear "
3319				"UNIT ATTENTION (err_mask=0x%x)\n", err_mask);
3320			return -EIO;
3321		}
3322	}
3323
3324	ata_dev_warn(dev, "UNIT ATTENTION persists after %d tries\n",
3325		     ATA_EH_UA_TRIES);
3326
3327	return 0;
3328}
3329
3330/**
3331 *	ata_eh_maybe_retry_flush - Retry FLUSH if necessary
3332 *	@dev: ATA device which may need FLUSH retry
3333 *
3334 *	If @dev failed FLUSH, it needs to be reported upper layer
3335 *	immediately as it means that @dev failed to remap and already
3336 *	lost at least a sector and further FLUSH retrials won't make
3337 *	any difference to the lost sector.  However, if FLUSH failed
3338 *	for other reasons, for example transmission error, FLUSH needs
3339 *	to be retried.
3340 *
3341 *	This function determines whether FLUSH failure retry is
3342 *	necessary and performs it if so.
3343 *
3344 *	RETURNS:
3345 *	0 if EH can continue, -errno if EH needs to be repeated.
3346 */
3347static int ata_eh_maybe_retry_flush(struct ata_device *dev)
3348{
3349	struct ata_link *link = dev->link;
3350	struct ata_port *ap = link->ap;
3351	struct ata_queued_cmd *qc;
3352	struct ata_taskfile tf;
3353	unsigned int err_mask;
3354	int rc = 0;
3355
3356	/* did flush fail for this device? */
3357	if (!ata_tag_valid(link->active_tag))
3358		return 0;
3359
3360	qc = __ata_qc_from_tag(ap, link->active_tag);
3361	if (qc->dev != dev || (qc->tf.command != ATA_CMD_FLUSH_EXT &&
3362			       qc->tf.command != ATA_CMD_FLUSH))
3363		return 0;
3364
3365	/* if the device failed it, it should be reported to upper layers */
3366	if (qc->err_mask & AC_ERR_DEV)
3367		return 0;
3368
3369	/* flush failed for some other reason, give it another shot */
3370	ata_tf_init(dev, &tf);
3371
3372	tf.command = qc->tf.command;
3373	tf.flags |= ATA_TFLAG_DEVICE;
3374	tf.protocol = ATA_PROT_NODATA;
3375
3376	ata_dev_warn(dev, "retrying FLUSH 0x%x Emask 0x%x\n",
3377		       tf.command, qc->err_mask);
3378
3379	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
3380	if (!err_mask) {
3381		/*
3382		 * FLUSH is complete but there's no way to
3383		 * successfully complete a failed command from EH.
3384		 * Making sure retry is allowed at least once and
3385		 * retrying it should do the trick - whatever was in
3386		 * the cache is already on the platter and this won't
3387		 * cause infinite loop.
3388		 */
3389		qc->scsicmd->allowed = max(qc->scsicmd->allowed, 1);
3390	} else {
3391		ata_dev_warn(dev, "FLUSH failed Emask 0x%x\n",
3392			       err_mask);
3393		rc = -EIO;
3394
3395		/* if device failed it, report it to upper layers */
3396		if (err_mask & AC_ERR_DEV) {
3397			qc->err_mask |= AC_ERR_DEV;
3398			qc->result_tf = tf;
3399			if (!(ap->pflags & ATA_PFLAG_FROZEN))
3400				rc = 0;
3401		}
3402	}
3403	return rc;
3404}
3405
3406/**
3407 *	ata_eh_set_lpm - configure SATA interface power management
3408 *	@link: link to configure power management
3409 *	@policy: the link power management policy
3410 *	@r_failed_dev: out parameter for failed device
3411 *
3412 *	Enable SATA Interface power management.  This will enable
3413 *	Device Interface Power Management (DIPM) for min_power
3414 * 	policy, and then call driver specific callbacks for
3415 *	enabling Host Initiated Power management.
3416 *
3417 *	LOCKING:
3418 *	EH context.
3419 *
3420 *	RETURNS:
3421 *	0 on success, -errno on failure.
3422 */
3423static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
3424			  struct ata_device **r_failed_dev)
3425{
3426	struct ata_port *ap = ata_is_host_link(link) ? link->ap : NULL;
3427	struct ata_eh_context *ehc = &link->eh_context;
3428	struct ata_device *dev, *link_dev = NULL, *lpm_dev = NULL;
3429	enum ata_lpm_policy old_policy = link->lpm_policy;
3430	bool no_dipm = link->ap->flags & ATA_FLAG_NO_DIPM;
3431	unsigned int hints = ATA_LPM_EMPTY | ATA_LPM_HIPM;
3432	unsigned int err_mask;
3433	int rc;
3434
3435	/* if the link or host doesn't do LPM, noop */
3436	if ((link->flags & ATA_LFLAG_NO_LPM) || (ap && !ap->ops->set_lpm))
 
3437		return 0;
3438
3439	/*
3440	 * DIPM is enabled only for MIN_POWER as some devices
3441	 * misbehave when the host NACKs transition to SLUMBER.  Order
3442	 * device and link configurations such that the host always
3443	 * allows DIPM requests.
3444	 */
3445	ata_for_each_dev(dev, link, ENABLED) {
3446		bool hipm = ata_id_has_hipm(dev->id);
3447		bool dipm = ata_id_has_dipm(dev->id) && !no_dipm;
3448
3449		/* find the first enabled and LPM enabled devices */
3450		if (!link_dev)
3451			link_dev = dev;
3452
3453		if (!lpm_dev && (hipm || dipm))
3454			lpm_dev = dev;
3455
3456		hints &= ~ATA_LPM_EMPTY;
3457		if (!hipm)
3458			hints &= ~ATA_LPM_HIPM;
3459
3460		/* disable DIPM before changing link config */
3461		if (policy != ATA_LPM_MIN_POWER && dipm) {
3462			err_mask = ata_dev_set_feature(dev,
3463					SETFEATURES_SATA_DISABLE, SATA_DIPM);
3464			if (err_mask && err_mask != AC_ERR_DEV) {
3465				ata_dev_warn(dev,
3466					     "failed to disable DIPM, Emask 0x%x\n",
3467					     err_mask);
3468				rc = -EIO;
3469				goto fail;
3470			}
3471		}
3472	}
3473
3474	if (ap) {
3475		rc = ap->ops->set_lpm(link, policy, hints);
3476		if (!rc && ap->slave_link)
3477			rc = ap->ops->set_lpm(ap->slave_link, policy, hints);
3478	} else
3479		rc = sata_pmp_set_lpm(link, policy, hints);
3480
3481	/*
3482	 * Attribute link config failure to the first (LPM) enabled
3483	 * device on the link.
3484	 */
3485	if (rc) {
3486		if (rc == -EOPNOTSUPP) {
3487			link->flags |= ATA_LFLAG_NO_LPM;
3488			return 0;
3489		}
3490		dev = lpm_dev ? lpm_dev : link_dev;
3491		goto fail;
3492	}
3493
3494	/*
3495	 * Low level driver acked the transition.  Issue DIPM command
3496	 * with the new policy set.
3497	 */
3498	link->lpm_policy = policy;
3499	if (ap && ap->slave_link)
3500		ap->slave_link->lpm_policy = policy;
3501
3502	/* host config updated, enable DIPM if transitioning to MIN_POWER */
3503	ata_for_each_dev(dev, link, ENABLED) {
3504		if (policy == ATA_LPM_MIN_POWER && !no_dipm &&
3505		    ata_id_has_dipm(dev->id)) {
3506			err_mask = ata_dev_set_feature(dev,
3507					SETFEATURES_SATA_ENABLE, SATA_DIPM);
3508			if (err_mask && err_mask != AC_ERR_DEV) {
3509				ata_dev_warn(dev,
3510					"failed to enable DIPM, Emask 0x%x\n",
3511					err_mask);
3512				rc = -EIO;
3513				goto fail;
3514			}
3515		}
3516	}
3517
3518	link->last_lpm_change = jiffies;
3519	link->flags |= ATA_LFLAG_CHANGED;
3520
3521	return 0;
3522
3523fail:
3524	/* restore the old policy */
3525	link->lpm_policy = old_policy;
3526	if (ap && ap->slave_link)
3527		ap->slave_link->lpm_policy = old_policy;
3528
3529	/* if no device or only one more chance is left, disable LPM */
3530	if (!dev || ehc->tries[dev->devno] <= 2) {
3531		ata_link_warn(link, "disabling LPM on the link\n");
3532		link->flags |= ATA_LFLAG_NO_LPM;
3533	}
3534	if (r_failed_dev)
3535		*r_failed_dev = dev;
3536	return rc;
3537}
3538
3539int ata_link_nr_enabled(struct ata_link *link)
3540{
3541	struct ata_device *dev;
3542	int cnt = 0;
3543
3544	ata_for_each_dev(dev, link, ENABLED)
3545		cnt++;
3546	return cnt;
3547}
3548
3549static int ata_link_nr_vacant(struct ata_link *link)
3550{
3551	struct ata_device *dev;
3552	int cnt = 0;
3553
3554	ata_for_each_dev(dev, link, ALL)
3555		if (dev->class == ATA_DEV_UNKNOWN)
3556			cnt++;
3557	return cnt;
3558}
3559
3560static int ata_eh_skip_recovery(struct ata_link *link)
3561{
3562	struct ata_port *ap = link->ap;
3563	struct ata_eh_context *ehc = &link->eh_context;
3564	struct ata_device *dev;
3565
3566	/* skip disabled links */
3567	if (link->flags & ATA_LFLAG_DISABLED)
3568		return 1;
3569
3570	/* skip if explicitly requested */
3571	if (ehc->i.flags & ATA_EHI_NO_RECOVERY)
3572		return 1;
3573
3574	/* thaw frozen port and recover failed devices */
3575	if ((ap->pflags & ATA_PFLAG_FROZEN) || ata_link_nr_enabled(link))
3576		return 0;
3577
3578	/* reset at least once if reset is requested */
3579	if ((ehc->i.action & ATA_EH_RESET) &&
3580	    !(ehc->i.flags & ATA_EHI_DID_RESET))
3581		return 0;
3582
3583	/* skip if class codes for all vacant slots are ATA_DEV_NONE */
3584	ata_for_each_dev(dev, link, ALL) {
3585		if (dev->class == ATA_DEV_UNKNOWN &&
3586		    ehc->classes[dev->devno] != ATA_DEV_NONE)
3587			return 0;
3588	}
3589
3590	return 1;
3591}
3592
3593static int ata_count_probe_trials_cb(struct ata_ering_entry *ent, void *void_arg)
3594{
3595	u64 interval = msecs_to_jiffies(ATA_EH_PROBE_TRIAL_INTERVAL);
3596	u64 now = get_jiffies_64();
3597	int *trials = void_arg;
3598
3599	if ((ent->eflags & ATA_EFLAG_OLD_ER) ||
3600	    (ent->timestamp < now - min(now, interval)))
3601		return -1;
3602
3603	(*trials)++;
3604	return 0;
3605}
3606
3607static int ata_eh_schedule_probe(struct ata_device *dev)
3608{
3609	struct ata_eh_context *ehc = &dev->link->eh_context;
3610	struct ata_link *link = ata_dev_phys_link(dev);
3611	int trials = 0;
3612
3613	if (!(ehc->i.probe_mask & (1 << dev->devno)) ||
3614	    (ehc->did_probe_mask & (1 << dev->devno)))
3615		return 0;
3616
3617	ata_eh_detach_dev(dev);
3618	ata_dev_init(dev);
3619	ehc->did_probe_mask |= (1 << dev->devno);
3620	ehc->i.action |= ATA_EH_RESET;
3621	ehc->saved_xfer_mode[dev->devno] = 0;
3622	ehc->saved_ncq_enabled &= ~(1 << dev->devno);
3623
3624	/* the link maybe in a deep sleep, wake it up */
3625	if (link->lpm_policy > ATA_LPM_MAX_POWER) {
3626		if (ata_is_host_link(link))
3627			link->ap->ops->set_lpm(link, ATA_LPM_MAX_POWER,
3628					       ATA_LPM_EMPTY);
3629		else
3630			sata_pmp_set_lpm(link, ATA_LPM_MAX_POWER,
3631					 ATA_LPM_EMPTY);
3632	}
3633
3634	/* Record and count probe trials on the ering.  The specific
3635	 * error mask used is irrelevant.  Because a successful device
3636	 * detection clears the ering, this count accumulates only if
3637	 * there are consecutive failed probes.
3638	 *
3639	 * If the count is equal to or higher than ATA_EH_PROBE_TRIALS
3640	 * in the last ATA_EH_PROBE_TRIAL_INTERVAL, link speed is
3641	 * forced to 1.5Gbps.
3642	 *
3643	 * This is to work around cases where failed link speed
3644	 * negotiation results in device misdetection leading to
3645	 * infinite DEVXCHG or PHRDY CHG events.
3646	 */
3647	ata_ering_record(&dev->ering, 0, AC_ERR_OTHER);
3648	ata_ering_map(&dev->ering, ata_count_probe_trials_cb, &trials);
3649
3650	if (trials > ATA_EH_PROBE_TRIALS)
3651		sata_down_spd_limit(link, 1);
3652
3653	return 1;
3654}
3655
3656static int ata_eh_handle_dev_fail(struct ata_device *dev, int err)
3657{
3658	struct ata_eh_context *ehc = &dev->link->eh_context;
3659
3660	/* -EAGAIN from EH routine indicates retry without prejudice.
3661	 * The requester is responsible for ensuring forward progress.
3662	 */
3663	if (err != -EAGAIN)
3664		ehc->tries[dev->devno]--;
3665
3666	switch (err) {
3667	case -ENODEV:
3668		/* device missing or wrong IDENTIFY data, schedule probing */
3669		ehc->i.probe_mask |= (1 << dev->devno);
 
3670	case -EINVAL:
3671		/* give it just one more chance */
3672		ehc->tries[dev->devno] = min(ehc->tries[dev->devno], 1);
 
3673	case -EIO:
3674		if (ehc->tries[dev->devno] == 1) {
3675			/* This is the last chance, better to slow
3676			 * down than lose it.
3677			 */
3678			sata_down_spd_limit(ata_dev_phys_link(dev), 0);
3679			if (dev->pio_mode > XFER_PIO_0)
3680				ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
3681		}
3682	}
3683
3684	if (ata_dev_enabled(dev) && !ehc->tries[dev->devno]) {
3685		/* disable device if it has used up all its chances */
3686		ata_dev_disable(dev);
3687
3688		/* detach if offline */
3689		if (ata_phys_link_offline(ata_dev_phys_link(dev)))
3690			ata_eh_detach_dev(dev);
3691
3692		/* schedule probe if necessary */
3693		if (ata_eh_schedule_probe(dev)) {
3694			ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3695			memset(ehc->cmd_timeout_idx[dev->devno], 0,
3696			       sizeof(ehc->cmd_timeout_idx[dev->devno]));
3697		}
3698
3699		return 1;
3700	} else {
3701		ehc->i.action |= ATA_EH_RESET;
3702		return 0;
3703	}
3704}
3705
3706/**
3707 *	ata_eh_recover - recover host port after error
3708 *	@ap: host port to recover
3709 *	@prereset: prereset method (can be NULL)
3710 *	@softreset: softreset method (can be NULL)
3711 *	@hardreset: hardreset method (can be NULL)
3712 *	@postreset: postreset method (can be NULL)
3713 *	@r_failed_link: out parameter for failed link
3714 *
3715 *	This is the alpha and omega, eum and yang, heart and soul of
3716 *	libata exception handling.  On entry, actions required to
3717 *	recover each link and hotplug requests are recorded in the
3718 *	link's eh_context.  This function executes all the operations
3719 *	with appropriate retrials and fallbacks to resurrect failed
3720 *	devices, detach goners and greet newcomers.
3721 *
3722 *	LOCKING:
3723 *	Kernel thread context (may sleep).
3724 *
3725 *	RETURNS:
3726 *	0 on success, -errno on failure.
3727 */
3728int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
3729		   ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
3730		   ata_postreset_fn_t postreset,
3731		   struct ata_link **r_failed_link)
3732{
3733	struct ata_link *link;
3734	struct ata_device *dev;
3735	int rc, nr_fails;
3736	unsigned long flags, deadline;
3737
3738	DPRINTK("ENTER\n");
3739
3740	/* prep for recovery */
3741	ata_for_each_link(link, ap, EDGE) {
3742		struct ata_eh_context *ehc = &link->eh_context;
3743
3744		/* re-enable link? */
3745		if (ehc->i.action & ATA_EH_ENABLE_LINK) {
3746			ata_eh_about_to_do(link, NULL, ATA_EH_ENABLE_LINK);
3747			spin_lock_irqsave(ap->lock, flags);
3748			link->flags &= ~ATA_LFLAG_DISABLED;
3749			spin_unlock_irqrestore(ap->lock, flags);
3750			ata_eh_done(link, NULL, ATA_EH_ENABLE_LINK);
3751		}
3752
3753		ata_for_each_dev(dev, link, ALL) {
3754			if (link->flags & ATA_LFLAG_NO_RETRY)
3755				ehc->tries[dev->devno] = 1;
3756			else
3757				ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
3758
3759			/* collect port action mask recorded in dev actions */
3760			ehc->i.action |= ehc->i.dev_action[dev->devno] &
3761					 ~ATA_EH_PERDEV_MASK;
3762			ehc->i.dev_action[dev->devno] &= ATA_EH_PERDEV_MASK;
3763
3764			/* process hotplug request */
3765			if (dev->flags & ATA_DFLAG_DETACH)
3766				ata_eh_detach_dev(dev);
3767
3768			/* schedule probe if necessary */
3769			if (!ata_dev_enabled(dev))
3770				ata_eh_schedule_probe(dev);
3771		}
3772	}
3773
3774 retry:
3775	rc = 0;
3776
3777	/* if UNLOADING, finish immediately */
3778	if (ap->pflags & ATA_PFLAG_UNLOADING)
3779		goto out;
3780
3781	/* prep for EH */
3782	ata_for_each_link(link, ap, EDGE) {
3783		struct ata_eh_context *ehc = &link->eh_context;
3784
3785		/* skip EH if possible. */
3786		if (ata_eh_skip_recovery(link))
3787			ehc->i.action = 0;
3788
3789		ata_for_each_dev(dev, link, ALL)
3790			ehc->classes[dev->devno] = ATA_DEV_UNKNOWN;
3791	}
3792
3793	/* reset */
3794	ata_for_each_link(link, ap, EDGE) {
3795		struct ata_eh_context *ehc = &link->eh_context;
3796
3797		if (!(ehc->i.action & ATA_EH_RESET))
3798			continue;
3799
3800		rc = ata_eh_reset(link, ata_link_nr_vacant(link),
3801				  prereset, softreset, hardreset, postreset);
3802		if (rc) {
3803			ata_link_err(link, "reset failed, giving up\n");
3804			goto out;
3805		}
3806	}
3807
3808	do {
3809		unsigned long now;
3810
3811		/*
3812		 * clears ATA_EH_PARK in eh_info and resets
3813		 * ap->park_req_pending
3814		 */
3815		ata_eh_pull_park_action(ap);
3816
3817		deadline = jiffies;
3818		ata_for_each_link(link, ap, EDGE) {
3819			ata_for_each_dev(dev, link, ALL) {
3820				struct ata_eh_context *ehc = &link->eh_context;
3821				unsigned long tmp;
3822
3823				if (dev->class != ATA_DEV_ATA &&
3824				    dev->class != ATA_DEV_ZAC)
3825					continue;
3826				if (!(ehc->i.dev_action[dev->devno] &
3827				      ATA_EH_PARK))
3828					continue;
3829				tmp = dev->unpark_deadline;
3830				if (time_before(deadline, tmp))
3831					deadline = tmp;
3832				else if (time_before_eq(tmp, jiffies))
3833					continue;
3834				if (ehc->unloaded_mask & (1 << dev->devno))
3835					continue;
3836
3837				ata_eh_park_issue_cmd(dev, 1);
3838			}
3839		}
3840
3841		now = jiffies;
3842		if (time_before_eq(deadline, now))
3843			break;
3844
3845		ata_eh_release(ap);
3846		deadline = wait_for_completion_timeout(&ap->park_req_pending,
3847						       deadline - now);
3848		ata_eh_acquire(ap);
3849	} while (deadline);
3850	ata_for_each_link(link, ap, EDGE) {
3851		ata_for_each_dev(dev, link, ALL) {
3852			if (!(link->eh_context.unloaded_mask &
3853			      (1 << dev->devno)))
3854				continue;
3855
3856			ata_eh_park_issue_cmd(dev, 0);
3857			ata_eh_done(link, dev, ATA_EH_PARK);
3858		}
3859	}
3860
3861	/* the rest */
3862	nr_fails = 0;
3863	ata_for_each_link(link, ap, PMP_FIRST) {
3864		struct ata_eh_context *ehc = &link->eh_context;
3865
3866		if (sata_pmp_attached(ap) && ata_is_host_link(link))
3867			goto config_lpm;
3868
3869		/* revalidate existing devices and attach new ones */
3870		rc = ata_eh_revalidate_and_attach(link, &dev);
3871		if (rc)
3872			goto rest_fail;
3873
3874		/* if PMP got attached, return, pmp EH will take care of it */
3875		if (link->device->class == ATA_DEV_PMP) {
3876			ehc->i.action = 0;
3877			return 0;
3878		}
3879
3880		/* configure transfer mode if necessary */
3881		if (ehc->i.flags & ATA_EHI_SETMODE) {
3882			rc = ata_set_mode(link, &dev);
3883			if (rc)
3884				goto rest_fail;
3885			ehc->i.flags &= ~ATA_EHI_SETMODE;
3886		}
3887
3888		/* If reset has been issued, clear UA to avoid
3889		 * disrupting the current users of the device.
3890		 */
3891		if (ehc->i.flags & ATA_EHI_DID_RESET) {
3892			ata_for_each_dev(dev, link, ALL) {
3893				if (dev->class != ATA_DEV_ATAPI)
3894					continue;
3895				rc = atapi_eh_clear_ua(dev);
3896				if (rc)
3897					goto rest_fail;
3898				if (zpodd_dev_enabled(dev))
3899					zpodd_post_poweron(dev);
3900			}
3901		}
3902
 
 
 
 
 
 
 
 
 
 
 
3903		/* retry flush if necessary */
3904		ata_for_each_dev(dev, link, ALL) {
3905			if (dev->class != ATA_DEV_ATA &&
3906			    dev->class != ATA_DEV_ZAC)
3907				continue;
3908			rc = ata_eh_maybe_retry_flush(dev);
3909			if (rc)
3910				goto rest_fail;
3911		}
3912
3913	config_lpm:
3914		/* configure link power saving */
3915		if (link->lpm_policy != ap->target_lpm_policy) {
3916			rc = ata_eh_set_lpm(link, ap->target_lpm_policy, &dev);
3917			if (rc)
3918				goto rest_fail;
3919		}
3920
3921		/* this link is okay now */
3922		ehc->i.flags = 0;
3923		continue;
3924
3925	rest_fail:
3926		nr_fails++;
3927		if (dev)
3928			ata_eh_handle_dev_fail(dev, rc);
3929
3930		if (ap->pflags & ATA_PFLAG_FROZEN) {
3931			/* PMP reset requires working host port.
3932			 * Can't retry if it's frozen.
3933			 */
3934			if (sata_pmp_attached(ap))
3935				goto out;
3936			break;
3937		}
3938	}
3939
3940	if (nr_fails)
3941		goto retry;
3942
3943 out:
3944	if (rc && r_failed_link)
3945		*r_failed_link = link;
3946
3947	DPRINTK("EXIT, rc=%d\n", rc);
3948	return rc;
3949}
3950
3951/**
3952 *	ata_eh_finish - finish up EH
3953 *	@ap: host port to finish EH for
3954 *
3955 *	Recovery is complete.  Clean up EH states and retry or finish
3956 *	failed qcs.
3957 *
3958 *	LOCKING:
3959 *	None.
3960 */
3961void ata_eh_finish(struct ata_port *ap)
3962{
 
3963	int tag;
3964
3965	/* retry or finish qcs */
3966	for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
3967		struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
3968
3969		if (!(qc->flags & ATA_QCFLAG_FAILED))
3970			continue;
3971
3972		if (qc->err_mask) {
3973			/* FIXME: Once EH migration is complete,
3974			 * generate sense data in this function,
3975			 * considering both err_mask and tf.
3976			 */
3977			if (qc->flags & ATA_QCFLAG_RETRY)
 
 
 
 
 
 
3978				ata_eh_qc_retry(qc);
3979			else
3980				ata_eh_qc_complete(qc);
 
3981		} else {
3982			if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
 
3983				ata_eh_qc_complete(qc);
3984			} else {
3985				/* feed zero TF to sense generation */
3986				memset(&qc->result_tf, 0, sizeof(qc->result_tf));
 
 
 
 
 
 
3987				ata_eh_qc_retry(qc);
3988			}
3989		}
3990	}
3991
3992	/* make sure nr_active_links is zero after EH */
3993	WARN_ON(ap->nr_active_links);
3994	ap->nr_active_links = 0;
3995}
3996
3997/**
3998 *	ata_do_eh - do standard error handling
3999 *	@ap: host port to handle error for
4000 *
4001 *	@prereset: prereset method (can be NULL)
4002 *	@softreset: softreset method (can be NULL)
4003 *	@hardreset: hardreset method (can be NULL)
4004 *	@postreset: postreset method (can be NULL)
4005 *
4006 *	Perform standard error handling sequence.
4007 *
4008 *	LOCKING:
4009 *	Kernel thread context (may sleep).
4010 */
4011void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
4012	       ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
4013	       ata_postreset_fn_t postreset)
4014{
4015	struct ata_device *dev;
4016	int rc;
4017
4018	ata_eh_autopsy(ap);
4019	ata_eh_report(ap);
4020
4021	rc = ata_eh_recover(ap, prereset, softreset, hardreset, postreset,
4022			    NULL);
4023	if (rc) {
4024		ata_for_each_dev(dev, &ap->link, ALL)
4025			ata_dev_disable(dev);
4026	}
4027
4028	ata_eh_finish(ap);
4029}
4030
4031/**
4032 *	ata_std_error_handler - standard error handler
4033 *	@ap: host port to handle error for
4034 *
4035 *	Standard error handler
4036 *
4037 *	LOCKING:
4038 *	Kernel thread context (may sleep).
4039 */
4040void ata_std_error_handler(struct ata_port *ap)
4041{
4042	struct ata_port_operations *ops = ap->ops;
4043	ata_reset_fn_t hardreset = ops->hardreset;
4044
4045	/* ignore built-in hardreset if SCR access is not available */
4046	if (hardreset == sata_std_hardreset && !sata_scr_valid(&ap->link))
4047		hardreset = NULL;
4048
4049	ata_do_eh(ap, ops->prereset, ops->softreset, hardreset, ops->postreset);
4050}
 
4051
4052#ifdef CONFIG_PM
4053/**
4054 *	ata_eh_handle_port_suspend - perform port suspend operation
4055 *	@ap: port to suspend
4056 *
4057 *	Suspend @ap.
4058 *
4059 *	LOCKING:
4060 *	Kernel thread context (may sleep).
4061 */
4062static void ata_eh_handle_port_suspend(struct ata_port *ap)
4063{
4064	unsigned long flags;
4065	int rc = 0;
4066	struct ata_device *dev;
 
4067
4068	/* are we suspending? */
4069	spin_lock_irqsave(ap->lock, flags);
4070	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
4071	    ap->pm_mesg.event & PM_EVENT_RESUME) {
4072		spin_unlock_irqrestore(ap->lock, flags);
4073		return;
4074	}
4075	spin_unlock_irqrestore(ap->lock, flags);
4076
4077	WARN_ON(ap->pflags & ATA_PFLAG_SUSPENDED);
4078
 
 
 
 
 
 
4079	/*
4080	 * If we have a ZPODD attached, check its zero
4081	 * power ready status before the port is frozen.
4082	 * Only needed for runtime suspend.
4083	 */
4084	if (PMSG_IS_AUTO(ap->pm_mesg)) {
4085		ata_for_each_dev(dev, &ap->link, ENABLED) {
4086			if (zpodd_dev_enabled(dev))
4087				zpodd_on_suspend(dev);
4088		}
4089	}
4090
4091	/* tell ACPI we're suspending */
4092	rc = ata_acpi_on_suspend(ap);
4093	if (rc)
4094		goto out;
4095
4096	/* suspend */
4097	ata_eh_freeze_port(ap);
4098
4099	if (ap->ops->port_suspend)
4100		rc = ap->ops->port_suspend(ap, ap->pm_mesg);
4101
4102	ata_acpi_set_state(ap, ap->pm_mesg);
4103 out:
4104	/* update the flags */
4105	spin_lock_irqsave(ap->lock, flags);
4106
4107	ap->pflags &= ~ATA_PFLAG_PM_PENDING;
4108	if (rc == 0)
4109		ap->pflags |= ATA_PFLAG_SUSPENDED;
4110	else if (ap->pflags & ATA_PFLAG_FROZEN)
4111		ata_port_schedule_eh(ap);
4112
4113	spin_unlock_irqrestore(ap->lock, flags);
4114
4115	return;
4116}
4117
4118/**
4119 *	ata_eh_handle_port_resume - perform port resume operation
4120 *	@ap: port to resume
4121 *
4122 *	Resume @ap.
4123 *
4124 *	LOCKING:
4125 *	Kernel thread context (may sleep).
4126 */
4127static void ata_eh_handle_port_resume(struct ata_port *ap)
4128{
4129	struct ata_link *link;
4130	struct ata_device *dev;
4131	unsigned long flags;
4132	int rc = 0;
4133
4134	/* are we resuming? */
4135	spin_lock_irqsave(ap->lock, flags);
4136	if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
4137	    !(ap->pm_mesg.event & PM_EVENT_RESUME)) {
4138		spin_unlock_irqrestore(ap->lock, flags);
4139		return;
4140	}
4141	spin_unlock_irqrestore(ap->lock, flags);
4142
4143	WARN_ON(!(ap->pflags & ATA_PFLAG_SUSPENDED));
4144
4145	/*
4146	 * Error timestamps are in jiffies which doesn't run while
4147	 * suspended and PHY events during resume isn't too uncommon.
4148	 * When the two are combined, it can lead to unnecessary speed
4149	 * downs if the machine is suspended and resumed repeatedly.
4150	 * Clear error history.
4151	 */
4152	ata_for_each_link(link, ap, HOST_FIRST)
4153		ata_for_each_dev(dev, link, ALL)
4154			ata_ering_clear(&dev->ering);
4155
4156	ata_acpi_set_state(ap, ap->pm_mesg);
4157
4158	if (ap->ops->port_resume)
4159		rc = ap->ops->port_resume(ap);
4160
4161	/* tell ACPI that we're resuming */
4162	ata_acpi_on_resume(ap);
4163
4164	/* update the flags */
4165	spin_lock_irqsave(ap->lock, flags);
4166	ap->pflags &= ~(ATA_PFLAG_PM_PENDING | ATA_PFLAG_SUSPENDED);
 
4167	spin_unlock_irqrestore(ap->lock, flags);
4168}
4169#endif /* CONFIG_PM */
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 */