https://github.com/torvalds/linux
Tip revision: 99abfeafb5f2eea1bb481330ff37343e1133c924 authored by Linus Torvalds on 25 January 2007, 02:19:28 UTC
Linux 2.6.20-rc6
Linux 2.6.20-rc6
Tip revision: 99abfea
libata-eh.c
/*
* libata-eh.c - libata error handling
*
* Maintained by: Jeff Garzik <jgarzik@pobox.com>
* Please ALWAYS copy linux-ide@vger.kernel.org
* on emails.
*
* Copyright 2006 Tejun Heo <htejun@gmail.com>
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
* USA.
*
*
* libata documentation is available via 'make {ps|pdf}docs',
* as Documentation/DocBook/libata.*
*
* Hardware documentation available from http://www.t13.org/ and
* http://www.sata-io.org/
*
*/
#include <linux/kernel.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_cmnd.h>
#include "../scsi/scsi_transport_api.h"
#include <linux/libata.h>
#include "libata.h"
static void __ata_port_freeze(struct ata_port *ap);
static void ata_eh_finish(struct ata_port *ap);
static void ata_eh_handle_port_suspend(struct ata_port *ap);
static void ata_eh_handle_port_resume(struct ata_port *ap);
static void ata_ering_record(struct ata_ering *ering, int is_io,
unsigned int err_mask)
{
struct ata_ering_entry *ent;
WARN_ON(!err_mask);
ering->cursor++;
ering->cursor %= ATA_ERING_SIZE;
ent = &ering->ring[ering->cursor];
ent->is_io = is_io;
ent->err_mask = err_mask;
ent->timestamp = get_jiffies_64();
}
static struct ata_ering_entry * ata_ering_top(struct ata_ering *ering)
{
struct ata_ering_entry *ent = &ering->ring[ering->cursor];
if (!ent->err_mask)
return NULL;
return ent;
}
static int ata_ering_map(struct ata_ering *ering,
int (*map_fn)(struct ata_ering_entry *, void *),
void *arg)
{
int idx, rc = 0;
struct ata_ering_entry *ent;
idx = ering->cursor;
do {
ent = &ering->ring[idx];
if (!ent->err_mask)
break;
rc = map_fn(ent, arg);
if (rc)
break;
idx = (idx - 1 + ATA_ERING_SIZE) % ATA_ERING_SIZE;
} while (idx != ering->cursor);
return rc;
}
static unsigned int ata_eh_dev_action(struct ata_device *dev)
{
struct ata_eh_context *ehc = &dev->ap->eh_context;
return ehc->i.action | ehc->i.dev_action[dev->devno];
}
static void ata_eh_clear_action(struct ata_device *dev,
struct ata_eh_info *ehi, unsigned int action)
{
int i;
if (!dev) {
ehi->action &= ~action;
for (i = 0; i < ATA_MAX_DEVICES; i++)
ehi->dev_action[i] &= ~action;
} else {
/* doesn't make sense for port-wide EH actions */
WARN_ON(!(action & ATA_EH_PERDEV_MASK));
/* break ehi->action into ehi->dev_action */
if (ehi->action & action) {
for (i = 0; i < ATA_MAX_DEVICES; i++)
ehi->dev_action[i] |= ehi->action & action;
ehi->action &= ~action;
}
/* turn off the specified per-dev action */
ehi->dev_action[dev->devno] &= ~action;
}
}
/**
* ata_scsi_timed_out - SCSI layer time out callback
* @cmd: timed out SCSI command
*
* Handles SCSI layer timeout. We race with normal completion of
* the qc for @cmd. If the qc is already gone, we lose and let
* the scsi command finish (EH_HANDLED). Otherwise, the qc has
* timed out and EH should be invoked. Prevent ata_qc_complete()
* from finishing it by setting EH_SCHEDULED and return
* EH_NOT_HANDLED.
*
* TODO: kill this function once old EH is gone.
*
* LOCKING:
* Called from timer context
*
* RETURNS:
* EH_HANDLED or EH_NOT_HANDLED
*/
enum scsi_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd)
{
struct Scsi_Host *host = cmd->device->host;
struct ata_port *ap = ata_shost_to_port(host);
unsigned long flags;
struct ata_queued_cmd *qc;
enum scsi_eh_timer_return ret;
DPRINTK("ENTER\n");
if (ap->ops->error_handler) {
ret = EH_NOT_HANDLED;
goto out;
}
ret = EH_HANDLED;
spin_lock_irqsave(ap->lock, flags);
qc = ata_qc_from_tag(ap, ap->active_tag);
if (qc) {
WARN_ON(qc->scsicmd != cmd);
qc->flags |= ATA_QCFLAG_EH_SCHEDULED;
qc->err_mask |= AC_ERR_TIMEOUT;
ret = EH_NOT_HANDLED;
}
spin_unlock_irqrestore(ap->lock, flags);
out:
DPRINTK("EXIT, ret=%d\n", ret);
return ret;
}
/**
* ata_scsi_error - SCSI layer error handler callback
* @host: SCSI host on which error occurred
*
* Handles SCSI-layer-thrown error events.
*
* LOCKING:
* Inherited from SCSI layer (none, can sleep)
*
* RETURNS:
* Zero.
*/
void ata_scsi_error(struct Scsi_Host *host)
{
struct ata_port *ap = ata_shost_to_port(host);
int i, repeat_cnt = ATA_EH_MAX_REPEAT;
unsigned long flags;
DPRINTK("ENTER\n");
/* synchronize with port task */
ata_port_flush_task(ap);
/* synchronize with host lock and sort out timeouts */
/* For new EH, all qcs are finished in one of three ways -
* normal completion, error completion, and SCSI timeout.
* Both cmpletions can race against SCSI timeout. When normal
* completion wins, the qc never reaches EH. When error
* completion wins, the qc has ATA_QCFLAG_FAILED set.
*
* When SCSI timeout wins, things are a bit more complex.
* Normal or error completion can occur after the timeout but
* before this point. In such cases, both types of
* completions are honored. A scmd is determined to have
* timed out iff its associated qc is active and not failed.
*/
if (ap->ops->error_handler) {
struct scsi_cmnd *scmd, *tmp;
int nr_timedout = 0;
spin_lock_irqsave(ap->lock, flags);
list_for_each_entry_safe(scmd, tmp, &host->eh_cmd_q, eh_entry) {
struct ata_queued_cmd *qc;
for (i = 0; i < ATA_MAX_QUEUE; i++) {
qc = __ata_qc_from_tag(ap, i);
if (qc->flags & ATA_QCFLAG_ACTIVE &&
qc->scsicmd == scmd)
break;
}
if (i < ATA_MAX_QUEUE) {
/* the scmd has an associated qc */
if (!(qc->flags & ATA_QCFLAG_FAILED)) {
/* which hasn't failed yet, timeout */
qc->err_mask |= AC_ERR_TIMEOUT;
qc->flags |= ATA_QCFLAG_FAILED;
nr_timedout++;
}
} else {
/* Normal completion occurred after
* SCSI timeout but before this point.
* Successfully complete it.
*/
scmd->retries = scmd->allowed;
scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
}
}
/* If we have timed out qcs. They belong to EH from
* this point but the state of the controller is
* unknown. Freeze the port to make sure the IRQ
* handler doesn't diddle with those qcs. This must
* be done atomically w.r.t. setting QCFLAG_FAILED.
*/
if (nr_timedout)
__ata_port_freeze(ap);
spin_unlock_irqrestore(ap->lock, flags);
} else
spin_unlock_wait(ap->lock);
repeat:
/* invoke error handler */
if (ap->ops->error_handler) {
/* process port resume request */
ata_eh_handle_port_resume(ap);
/* fetch & clear EH info */
spin_lock_irqsave(ap->lock, flags);
memset(&ap->eh_context, 0, sizeof(ap->eh_context));
ap->eh_context.i = ap->eh_info;
memset(&ap->eh_info, 0, sizeof(ap->eh_info));
ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
ap->pflags &= ~ATA_PFLAG_EH_PENDING;
spin_unlock_irqrestore(ap->lock, flags);
/* invoke EH, skip if unloading or suspended */
if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))
ap->ops->error_handler(ap);
else
ata_eh_finish(ap);
/* process port suspend request */
ata_eh_handle_port_suspend(ap);
/* Exception might have happend after ->error_handler
* recovered the port but before this point. Repeat
* EH in such case.
*/
spin_lock_irqsave(ap->lock, flags);
if (ap->pflags & ATA_PFLAG_EH_PENDING) {
if (--repeat_cnt) {
ata_port_printk(ap, KERN_INFO,
"EH pending after completion, "
"repeating EH (cnt=%d)\n", repeat_cnt);
spin_unlock_irqrestore(ap->lock, flags);
goto repeat;
}
ata_port_printk(ap, KERN_ERR, "EH pending after %d "
"tries, giving up\n", ATA_EH_MAX_REPEAT);
}
/* this run is complete, make sure EH info is clear */
memset(&ap->eh_info, 0, sizeof(ap->eh_info));
/* Clear host_eh_scheduled while holding ap->lock such
* that if exception occurs after this point but
* before EH completion, SCSI midlayer will
* re-initiate EH.
*/
host->host_eh_scheduled = 0;
spin_unlock_irqrestore(ap->lock, flags);
} else {
WARN_ON(ata_qc_from_tag(ap, ap->active_tag) == NULL);
ap->ops->eng_timeout(ap);
}
/* finish or retry handled scmd's and clean up */
WARN_ON(host->host_failed || !list_empty(&host->eh_cmd_q));
scsi_eh_flush_done_q(&ap->eh_done_q);
/* clean up */
spin_lock_irqsave(ap->lock, flags);
if (ap->pflags & ATA_PFLAG_LOADING)
ap->pflags &= ~ATA_PFLAG_LOADING;
else if (ap->pflags & ATA_PFLAG_SCSI_HOTPLUG)
queue_delayed_work(ata_aux_wq, &ap->hotplug_task, 0);
if (ap->pflags & ATA_PFLAG_RECOVERED)
ata_port_printk(ap, KERN_INFO, "EH complete\n");
ap->pflags &= ~(ATA_PFLAG_SCSI_HOTPLUG | ATA_PFLAG_RECOVERED);
/* tell wait_eh that we're done */
ap->pflags &= ~ATA_PFLAG_EH_IN_PROGRESS;
wake_up_all(&ap->eh_wait_q);
spin_unlock_irqrestore(ap->lock, flags);
DPRINTK("EXIT\n");
}
/**
* ata_port_wait_eh - Wait for the currently pending EH to complete
* @ap: Port to wait EH for
*
* Wait until the currently pending EH is complete.
*
* LOCKING:
* Kernel thread context (may sleep).
*/
void ata_port_wait_eh(struct ata_port *ap)
{
unsigned long flags;
DEFINE_WAIT(wait);
retry:
spin_lock_irqsave(ap->lock, flags);
while (ap->pflags & (ATA_PFLAG_EH_PENDING | ATA_PFLAG_EH_IN_PROGRESS)) {
prepare_to_wait(&ap->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE);
spin_unlock_irqrestore(ap->lock, flags);
schedule();
spin_lock_irqsave(ap->lock, flags);
}
finish_wait(&ap->eh_wait_q, &wait);
spin_unlock_irqrestore(ap->lock, flags);
/* make sure SCSI EH is complete */
if (scsi_host_in_recovery(ap->scsi_host)) {
msleep(10);
goto retry;
}
}
/**
* ata_qc_timeout - Handle timeout of queued command
* @qc: Command that timed out
*
* Some part of the kernel (currently, only the SCSI layer)
* has noticed that the active command on port @ap has not
* completed after a specified length of time. Handle this
* condition by disabling DMA (if necessary) and completing
* transactions, with error if necessary.
*
* This also handles the case of the "lost interrupt", where
* for some reason (possibly hardware bug, possibly driver bug)
* an interrupt was not delivered to the driver, even though the
* transaction completed successfully.
*
* TODO: kill this function once old EH is gone.
*
* LOCKING:
* Inherited from SCSI layer (none, can sleep)
*/
static void ata_qc_timeout(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
u8 host_stat = 0, drv_stat;
unsigned long flags;
DPRINTK("ENTER\n");
ap->hsm_task_state = HSM_ST_IDLE;
spin_lock_irqsave(ap->lock, flags);
switch (qc->tf.protocol) {
case ATA_PROT_DMA:
case ATA_PROT_ATAPI_DMA:
host_stat = ap->ops->bmdma_status(ap);
/* before we do anything else, clear DMA-Start bit */
ap->ops->bmdma_stop(qc);
/* fall through */
default:
ata_altstatus(ap);
drv_stat = ata_chk_status(ap);
/* ack bmdma irq events */
ap->ops->irq_clear(ap);
ata_dev_printk(qc->dev, KERN_ERR, "command 0x%x timeout, "
"stat 0x%x host_stat 0x%x\n",
qc->tf.command, drv_stat, host_stat);
/* complete taskfile transaction */
qc->err_mask |= AC_ERR_TIMEOUT;
break;
}
spin_unlock_irqrestore(ap->lock, flags);
ata_eh_qc_complete(qc);
DPRINTK("EXIT\n");
}
/**
* ata_eng_timeout - Handle timeout of queued command
* @ap: Port on which timed-out command is active
*
* Some part of the kernel (currently, only the SCSI layer)
* has noticed that the active command on port @ap has not
* completed after a specified length of time. Handle this
* condition by disabling DMA (if necessary) and completing
* transactions, with error if necessary.
*
* This also handles the case of the "lost interrupt", where
* for some reason (possibly hardware bug, possibly driver bug)
* an interrupt was not delivered to the driver, even though the
* transaction completed successfully.
*
* TODO: kill this function once old EH is gone.
*
* LOCKING:
* Inherited from SCSI layer (none, can sleep)
*/
void ata_eng_timeout(struct ata_port *ap)
{
DPRINTK("ENTER\n");
ata_qc_timeout(ata_qc_from_tag(ap, ap->active_tag));
DPRINTK("EXIT\n");
}
/**
* ata_qc_schedule_eh - schedule qc for error handling
* @qc: command to schedule error handling for
*
* Schedule error handling for @qc. EH will kick in as soon as
* other commands are drained.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
WARN_ON(!ap->ops->error_handler);
qc->flags |= ATA_QCFLAG_FAILED;
qc->ap->pflags |= ATA_PFLAG_EH_PENDING;
/* The following will fail if timeout has already expired.
* ata_scsi_error() takes care of such scmds on EH entry.
* Note that ATA_QCFLAG_FAILED is unconditionally set after
* this function completes.
*/
scsi_req_abort_cmd(qc->scsicmd);
}
/**
* ata_port_schedule_eh - schedule error handling without a qc
* @ap: ATA port to schedule EH for
*
* Schedule error handling for @ap. EH will kick in as soon as
* all commands are drained.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
void ata_port_schedule_eh(struct ata_port *ap)
{
WARN_ON(!ap->ops->error_handler);
ap->pflags |= ATA_PFLAG_EH_PENDING;
scsi_schedule_eh(ap->scsi_host);
DPRINTK("port EH scheduled\n");
}
/**
* ata_port_abort - abort all qc's on the port
* @ap: ATA port to abort qc's for
*
* Abort all active qc's of @ap and schedule EH.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*
* RETURNS:
* Number of aborted qc's.
*/
int ata_port_abort(struct ata_port *ap)
{
int tag, nr_aborted = 0;
WARN_ON(!ap->ops->error_handler);
for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag);
if (qc) {
qc->flags |= ATA_QCFLAG_FAILED;
ata_qc_complete(qc);
nr_aborted++;
}
}
if (!nr_aborted)
ata_port_schedule_eh(ap);
return nr_aborted;
}
/**
* __ata_port_freeze - freeze port
* @ap: ATA port to freeze
*
* This function is called when HSM violation or some other
* condition disrupts normal operation of the port. Frozen port
* is not allowed to perform any operation until the port is
* thawed, which usually follows a successful reset.
*
* ap->ops->freeze() callback can be used for freezing the port
* hardware-wise (e.g. mask interrupt and stop DMA engine). If a
* port cannot be frozen hardware-wise, the interrupt handler
* must ack and clear interrupts unconditionally while the port
* is frozen.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
static void __ata_port_freeze(struct ata_port *ap)
{
WARN_ON(!ap->ops->error_handler);
if (ap->ops->freeze)
ap->ops->freeze(ap);
ap->pflags |= ATA_PFLAG_FROZEN;
DPRINTK("ata%u port frozen\n", ap->id);
}
/**
* ata_port_freeze - abort & freeze port
* @ap: ATA port to freeze
*
* Abort and freeze @ap.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*
* RETURNS:
* Number of aborted commands.
*/
int ata_port_freeze(struct ata_port *ap)
{
int nr_aborted;
WARN_ON(!ap->ops->error_handler);
nr_aborted = ata_port_abort(ap);
__ata_port_freeze(ap);
return nr_aborted;
}
/**
* ata_eh_freeze_port - EH helper to freeze port
* @ap: ATA port to freeze
*
* Freeze @ap.
*
* LOCKING:
* None.
*/
void ata_eh_freeze_port(struct ata_port *ap)
{
unsigned long flags;
if (!ap->ops->error_handler)
return;
spin_lock_irqsave(ap->lock, flags);
__ata_port_freeze(ap);
spin_unlock_irqrestore(ap->lock, flags);
}
/**
* ata_port_thaw_port - EH helper to thaw port
* @ap: ATA port to thaw
*
* Thaw frozen port @ap.
*
* LOCKING:
* None.
*/
void ata_eh_thaw_port(struct ata_port *ap)
{
unsigned long flags;
if (!ap->ops->error_handler)
return;
spin_lock_irqsave(ap->lock, flags);
ap->pflags &= ~ATA_PFLAG_FROZEN;
if (ap->ops->thaw)
ap->ops->thaw(ap);
spin_unlock_irqrestore(ap->lock, flags);
DPRINTK("ata%u port thawed\n", ap->id);
}
static void ata_eh_scsidone(struct scsi_cmnd *scmd)
{
/* nada */
}
static void __ata_eh_qc_complete(struct ata_queued_cmd *qc)
{
struct ata_port *ap = qc->ap;
struct scsi_cmnd *scmd = qc->scsicmd;
unsigned long flags;
spin_lock_irqsave(ap->lock, flags);
qc->scsidone = ata_eh_scsidone;
__ata_qc_complete(qc);
WARN_ON(ata_tag_valid(qc->tag));
spin_unlock_irqrestore(ap->lock, flags);
scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
}
/**
* ata_eh_qc_complete - Complete an active ATA command from EH
* @qc: Command to complete
*
* Indicate to the mid and upper layers that an ATA command has
* completed. To be used from EH.
*/
void ata_eh_qc_complete(struct ata_queued_cmd *qc)
{
struct scsi_cmnd *scmd = qc->scsicmd;
scmd->retries = scmd->allowed;
__ata_eh_qc_complete(qc);
}
/**
* ata_eh_qc_retry - Tell midlayer to retry an ATA command after EH
* @qc: Command to retry
*
* Indicate to the mid and upper layers that an ATA command
* should be retried. To be used from EH.
*
* SCSI midlayer limits the number of retries to scmd->allowed.
* scmd->retries is decremented for commands which get retried
* due to unrelated failures (qc->err_mask is zero).
*/
void ata_eh_qc_retry(struct ata_queued_cmd *qc)
{
struct scsi_cmnd *scmd = qc->scsicmd;
if (!qc->err_mask && scmd->retries)
scmd->retries--;
__ata_eh_qc_complete(qc);
}
/**
* ata_eh_detach_dev - detach ATA device
* @dev: ATA device to detach
*
* Detach @dev.
*
* LOCKING:
* None.
*/
static void ata_eh_detach_dev(struct ata_device *dev)
{
struct ata_port *ap = dev->ap;
unsigned long flags;
ata_dev_disable(dev);
spin_lock_irqsave(ap->lock, flags);
dev->flags &= ~ATA_DFLAG_DETACH;
if (ata_scsi_offline_dev(dev)) {
dev->flags |= ATA_DFLAG_DETACHED;
ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
}
/* clear per-dev EH actions */
ata_eh_clear_action(dev, &ap->eh_info, ATA_EH_PERDEV_MASK);
ata_eh_clear_action(dev, &ap->eh_context.i, ATA_EH_PERDEV_MASK);
spin_unlock_irqrestore(ap->lock, flags);
}
/**
* ata_eh_about_to_do - about to perform eh_action
* @ap: target ATA port
* @dev: target ATA dev for per-dev action (can be NULL)
* @action: action about to be performed
*
* Called just before performing EH actions to clear related bits
* in @ap->eh_info such that eh actions are not unnecessarily
* repeated.
*
* LOCKING:
* None.
*/
static void ata_eh_about_to_do(struct ata_port *ap, struct ata_device *dev,
unsigned int action)
{
unsigned long flags;
struct ata_eh_info *ehi = &ap->eh_info;
struct ata_eh_context *ehc = &ap->eh_context;
spin_lock_irqsave(ap->lock, flags);
/* Reset is represented by combination of actions and EHI
* flags. Suck in all related bits before clearing eh_info to
* avoid losing requested action.
*/
if (action & ATA_EH_RESET_MASK) {
ehc->i.action |= ehi->action & ATA_EH_RESET_MASK;
ehc->i.flags |= ehi->flags & ATA_EHI_RESET_MODIFIER_MASK;
/* make sure all reset actions are cleared & clear EHI flags */
action |= ATA_EH_RESET_MASK;
ehi->flags &= ~ATA_EHI_RESET_MODIFIER_MASK;
}
ata_eh_clear_action(dev, ehi, action);
if (!(ehc->i.flags & ATA_EHI_QUIET))
ap->pflags |= ATA_PFLAG_RECOVERED;
spin_unlock_irqrestore(ap->lock, flags);
}
/**
* ata_eh_done - EH action complete
* @ap: target ATA port
* @dev: target ATA dev for per-dev action (can be NULL)
* @action: action just completed
*
* Called right after performing EH actions to clear related bits
* in @ap->eh_context.
*
* LOCKING:
* None.
*/
static void ata_eh_done(struct ata_port *ap, struct ata_device *dev,
unsigned int action)
{
/* if reset is complete, clear all reset actions & reset modifier */
if (action & ATA_EH_RESET_MASK) {
action |= ATA_EH_RESET_MASK;
ap->eh_context.i.flags &= ~ATA_EHI_RESET_MODIFIER_MASK;
}
ata_eh_clear_action(dev, &ap->eh_context.i, action);
}
/**
* ata_err_string - convert err_mask to descriptive string
* @err_mask: error mask to convert to string
*
* Convert @err_mask to descriptive string. Errors are
* prioritized according to severity and only the most severe
* error is reported.
*
* LOCKING:
* None.
*
* RETURNS:
* Descriptive string for @err_mask
*/
static const char * ata_err_string(unsigned int err_mask)
{
if (err_mask & AC_ERR_HOST_BUS)
return "host bus error";
if (err_mask & AC_ERR_ATA_BUS)
return "ATA bus error";
if (err_mask & AC_ERR_TIMEOUT)
return "timeout";
if (err_mask & AC_ERR_HSM)
return "HSM violation";
if (err_mask & AC_ERR_SYSTEM)
return "internal error";
if (err_mask & AC_ERR_MEDIA)
return "media error";
if (err_mask & AC_ERR_INVALID)
return "invalid argument";
if (err_mask & AC_ERR_DEV)
return "device error";
return "unknown error";
}
/**
* ata_read_log_page - read a specific log page
* @dev: target device
* @page: page to read
* @buf: buffer to store read page
* @sectors: number of sectors to read
*
* Read log page using READ_LOG_EXT command.
*
* LOCKING:
* Kernel thread context (may sleep).
*
* RETURNS:
* 0 on success, AC_ERR_* mask otherwise.
*/
static unsigned int ata_read_log_page(struct ata_device *dev,
u8 page, void *buf, unsigned int sectors)
{
struct ata_taskfile tf;
unsigned int err_mask;
DPRINTK("read log page - page %d\n", page);
ata_tf_init(dev, &tf);
tf.command = ATA_CMD_READ_LOG_EXT;
tf.lbal = page;
tf.nsect = sectors;
tf.hob_nsect = sectors >> 8;
tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_LBA48 | ATA_TFLAG_DEVICE;
tf.protocol = ATA_PROT_PIO;
err_mask = ata_exec_internal(dev, &tf, NULL, DMA_FROM_DEVICE,
buf, sectors * ATA_SECT_SIZE);
DPRINTK("EXIT, err_mask=%x\n", err_mask);
return err_mask;
}
/**
* ata_eh_read_log_10h - Read log page 10h for NCQ error details
* @dev: Device to read log page 10h from
* @tag: Resulting tag of the failed command
* @tf: Resulting taskfile registers of the failed command
*
* Read log page 10h to obtain NCQ error details and clear error
* condition.
*
* LOCKING:
* Kernel thread context (may sleep).
*
* RETURNS:
* 0 on success, -errno otherwise.
*/
static int ata_eh_read_log_10h(struct ata_device *dev,
int *tag, struct ata_taskfile *tf)
{
u8 *buf = dev->ap->sector_buf;
unsigned int err_mask;
u8 csum;
int i;
err_mask = ata_read_log_page(dev, ATA_LOG_SATA_NCQ, buf, 1);
if (err_mask)
return -EIO;
csum = 0;
for (i = 0; i < ATA_SECT_SIZE; i++)
csum += buf[i];
if (csum)
ata_dev_printk(dev, KERN_WARNING,
"invalid checksum 0x%x on log page 10h\n", csum);
if (buf[0] & 0x80)
return -ENOENT;
*tag = buf[0] & 0x1f;
tf->command = buf[2];
tf->feature = buf[3];
tf->lbal = buf[4];
tf->lbam = buf[5];
tf->lbah = buf[6];
tf->device = buf[7];
tf->hob_lbal = buf[8];
tf->hob_lbam = buf[9];
tf->hob_lbah = buf[10];
tf->nsect = buf[12];
tf->hob_nsect = buf[13];
return 0;
}
/**
* atapi_eh_request_sense - perform ATAPI REQUEST_SENSE
* @dev: device to perform REQUEST_SENSE to
* @sense_buf: result sense data buffer (SCSI_SENSE_BUFFERSIZE bytes long)
*
* Perform ATAPI REQUEST_SENSE after the device reported CHECK
* SENSE. This function is EH helper.
*
* LOCKING:
* Kernel thread context (may sleep).
*
* RETURNS:
* 0 on success, AC_ERR_* mask on failure
*/
static unsigned int atapi_eh_request_sense(struct ata_device *dev,
unsigned char *sense_buf)
{
struct ata_port *ap = dev->ap;
struct ata_taskfile tf;
u8 cdb[ATAPI_CDB_LEN];
DPRINTK("ATAPI request sense\n");
ata_tf_init(dev, &tf);
/* FIXME: is this needed? */
memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
/* XXX: why tf_read here? */
ap->ops->tf_read(ap, &tf);
/* fill these in, for the case where they are -not- overwritten */
sense_buf[0] = 0x70;
sense_buf[2] = tf.feature >> 4;
memset(cdb, 0, ATAPI_CDB_LEN);
cdb[0] = REQUEST_SENSE;
cdb[4] = SCSI_SENSE_BUFFERSIZE;
tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
tf.command = ATA_CMD_PACKET;
/* is it pointless to prefer PIO for "safety reasons"? */
if (ap->flags & ATA_FLAG_PIO_DMA) {
tf.protocol = ATA_PROT_ATAPI_DMA;
tf.feature |= ATAPI_PKT_DMA;
} else {
tf.protocol = ATA_PROT_ATAPI;
tf.lbam = (8 * 1024) & 0xff;
tf.lbah = (8 * 1024) >> 8;
}
return ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
sense_buf, SCSI_SENSE_BUFFERSIZE);
}
/**
* ata_eh_analyze_serror - analyze SError for a failed port
* @ap: ATA port to analyze SError for
*
* Analyze SError if available and further determine cause of
* failure.
*
* LOCKING:
* None.
*/
static void ata_eh_analyze_serror(struct ata_port *ap)
{
struct ata_eh_context *ehc = &ap->eh_context;
u32 serror = ehc->i.serror;
unsigned int err_mask = 0, action = 0;
if (serror & SERR_PERSISTENT) {
err_mask |= AC_ERR_ATA_BUS;
action |= ATA_EH_HARDRESET;
}
if (serror &
(SERR_DATA_RECOVERED | SERR_COMM_RECOVERED | SERR_DATA)) {
err_mask |= AC_ERR_ATA_BUS;
action |= ATA_EH_SOFTRESET;
}
if (serror & SERR_PROTOCOL) {
err_mask |= AC_ERR_HSM;
action |= ATA_EH_SOFTRESET;
}
if (serror & SERR_INTERNAL) {
err_mask |= AC_ERR_SYSTEM;
action |= ATA_EH_SOFTRESET;
}
if (serror & (SERR_PHYRDY_CHG | SERR_DEV_XCHG))
ata_ehi_hotplugged(&ehc->i);
ehc->i.err_mask |= err_mask;
ehc->i.action |= action;
}
/**
* ata_eh_analyze_ncq_error - analyze NCQ error
* @ap: ATA port to analyze NCQ error for
*
* Read log page 10h, determine the offending qc and acquire
* error status TF. For NCQ device errors, all LLDDs have to do
* is setting AC_ERR_DEV in ehi->err_mask. This function takes
* care of the rest.
*
* LOCKING:
* Kernel thread context (may sleep).
*/
static void ata_eh_analyze_ncq_error(struct ata_port *ap)
{
struct ata_eh_context *ehc = &ap->eh_context;
struct ata_device *dev = ap->device;
struct ata_queued_cmd *qc;
struct ata_taskfile tf;
int tag, rc;
/* if frozen, we can't do much */
if (ap->pflags & ATA_PFLAG_FROZEN)
return;
/* is it NCQ device error? */
if (!ap->sactive || !(ehc->i.err_mask & AC_ERR_DEV))
return;
/* has LLDD analyzed already? */
for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
qc = __ata_qc_from_tag(ap, tag);
if (!(qc->flags & ATA_QCFLAG_FAILED))
continue;
if (qc->err_mask)
return;
}
/* okay, this error is ours */
rc = ata_eh_read_log_10h(dev, &tag, &tf);
if (rc) {
ata_port_printk(ap, KERN_ERR, "failed to read log page 10h "
"(errno=%d)\n", rc);
return;
}
if (!(ap->sactive & (1 << tag))) {
ata_port_printk(ap, KERN_ERR, "log page 10h reported "
"inactive tag %d\n", tag);
return;
}
/* we've got the perpetrator, condemn it */
qc = __ata_qc_from_tag(ap, tag);
memcpy(&qc->result_tf, &tf, sizeof(tf));
qc->err_mask |= AC_ERR_DEV;
ehc->i.err_mask &= ~AC_ERR_DEV;
}
/**
* ata_eh_analyze_tf - analyze taskfile of a failed qc
* @qc: qc to analyze
* @tf: Taskfile registers to analyze
*
* Analyze taskfile of @qc and further determine cause of
* failure. This function also requests ATAPI sense data if
* avaliable.
*
* LOCKING:
* Kernel thread context (may sleep).
*
* RETURNS:
* Determined recovery action
*/
static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc,
const struct ata_taskfile *tf)
{
unsigned int tmp, action = 0;
u8 stat = tf->command, err = tf->feature;
if ((stat & (ATA_BUSY | ATA_DRQ | ATA_DRDY)) != ATA_DRDY) {
qc->err_mask |= AC_ERR_HSM;
return ATA_EH_SOFTRESET;
}
if (!(qc->err_mask & AC_ERR_DEV))
return 0;
switch (qc->dev->class) {
case ATA_DEV_ATA:
if (err & ATA_ICRC)
qc->err_mask |= AC_ERR_ATA_BUS;
if (err & ATA_UNC)
qc->err_mask |= AC_ERR_MEDIA;
if (err & ATA_IDNF)
qc->err_mask |= AC_ERR_INVALID;
break;
case ATA_DEV_ATAPI:
if (!(qc->ap->pflags & ATA_PFLAG_FROZEN)) {
tmp = atapi_eh_request_sense(qc->dev,
qc->scsicmd->sense_buffer);
if (!tmp) {
/* ATA_QCFLAG_SENSE_VALID is used to
* tell atapi_qc_complete() that sense
* data is already valid.
*
* TODO: interpret sense data and set
* appropriate err_mask.
*/
qc->flags |= ATA_QCFLAG_SENSE_VALID;
} else
qc->err_mask |= tmp;
}
}
if (qc->err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT | AC_ERR_ATA_BUS))
action |= ATA_EH_SOFTRESET;
return action;
}
static int ata_eh_categorize_ering_entry(struct ata_ering_entry *ent)
{
if (ent->err_mask & (AC_ERR_ATA_BUS | AC_ERR_TIMEOUT))
return 1;
if (ent->is_io) {
if (ent->err_mask & AC_ERR_HSM)
return 1;
if ((ent->err_mask &
(AC_ERR_DEV|AC_ERR_MEDIA|AC_ERR_INVALID)) == AC_ERR_DEV)
return 2;
}
return 0;
}
struct speed_down_needed_arg {
u64 since;
int nr_errors[3];
};
static int speed_down_needed_cb(struct ata_ering_entry *ent, void *void_arg)
{
struct speed_down_needed_arg *arg = void_arg;
if (ent->timestamp < arg->since)
return -1;
arg->nr_errors[ata_eh_categorize_ering_entry(ent)]++;
return 0;
}
/**
* ata_eh_speed_down_needed - Determine wheter speed down is necessary
* @dev: Device of interest
*
* This function examines error ring of @dev and determines
* whether speed down is necessary. Speed down is necessary if
* there have been more than 3 of Cat-1 errors or 10 of Cat-2
* errors during last 15 minutes.
*
* Cat-1 errors are ATA_BUS, TIMEOUT for any command and HSM
* violation for known supported commands.
*
* Cat-2 errors are unclassified DEV error for known supported
* command.
*
* LOCKING:
* Inherited from caller.
*
* RETURNS:
* 1 if speed down is necessary, 0 otherwise
*/
static int ata_eh_speed_down_needed(struct ata_device *dev)
{
const u64 interval = 15LLU * 60 * HZ;
static const int err_limits[3] = { -1, 3, 10 };
struct speed_down_needed_arg arg;
struct ata_ering_entry *ent;
int err_cat;
u64 j64;
ent = ata_ering_top(&dev->ering);
if (!ent)
return 0;
err_cat = ata_eh_categorize_ering_entry(ent);
if (err_cat == 0)
return 0;
memset(&arg, 0, sizeof(arg));
j64 = get_jiffies_64();
if (j64 >= interval)
arg.since = j64 - interval;
else
arg.since = 0;
ata_ering_map(&dev->ering, speed_down_needed_cb, &arg);
return arg.nr_errors[err_cat] > err_limits[err_cat];
}
/**
* ata_eh_speed_down - record error and speed down if necessary
* @dev: Failed device
* @is_io: Did the device fail during normal IO?
* @err_mask: err_mask of the error
*
* Record error and examine error history to determine whether
* adjusting transmission speed is necessary. It also sets
* transmission limits appropriately if such adjustment is
* necessary.
*
* LOCKING:
* Kernel thread context (may sleep).
*
* RETURNS:
* 0 on success, -errno otherwise
*/
static int ata_eh_speed_down(struct ata_device *dev, int is_io,
unsigned int err_mask)
{
if (!err_mask)
return 0;
/* record error and determine whether speed down is necessary */
ata_ering_record(&dev->ering, is_io, err_mask);
if (!ata_eh_speed_down_needed(dev))
return 0;
/* speed down SATA link speed if possible */
if (sata_down_spd_limit(dev->ap) == 0)
return ATA_EH_HARDRESET;
/* lower transfer mode */
if (ata_down_xfermask_limit(dev, 0) == 0)
return ATA_EH_SOFTRESET;
ata_dev_printk(dev, KERN_ERR,
"speed down requested but no transfer mode left\n");
return 0;
}
/**
* ata_eh_autopsy - analyze error and determine recovery action
* @ap: ATA port to perform autopsy on
*
* Analyze why @ap failed and determine which recovery action is
* needed. This function also sets more detailed AC_ERR_* values
* and fills sense data for ATAPI CHECK SENSE.
*
* LOCKING:
* Kernel thread context (may sleep).
*/
static void ata_eh_autopsy(struct ata_port *ap)
{
struct ata_eh_context *ehc = &ap->eh_context;
unsigned int all_err_mask = 0;
int tag, is_io = 0;
u32 serror;
int rc;
DPRINTK("ENTER\n");
if (ehc->i.flags & ATA_EHI_NO_AUTOPSY)
return;
/* obtain and analyze SError */
rc = sata_scr_read(ap, SCR_ERROR, &serror);
if (rc == 0) {
ehc->i.serror |= serror;
ata_eh_analyze_serror(ap);
} else if (rc != -EOPNOTSUPP)
ehc->i.action |= ATA_EH_HARDRESET;
/* analyze NCQ failure */
ata_eh_analyze_ncq_error(ap);
/* any real error trumps AC_ERR_OTHER */
if (ehc->i.err_mask & ~AC_ERR_OTHER)
ehc->i.err_mask &= ~AC_ERR_OTHER;
all_err_mask |= ehc->i.err_mask;
for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
if (!(qc->flags & ATA_QCFLAG_FAILED))
continue;
/* inherit upper level err_mask */
qc->err_mask |= ehc->i.err_mask;
/* analyze TF */
ehc->i.action |= ata_eh_analyze_tf(qc, &qc->result_tf);
/* DEV errors are probably spurious in case of ATA_BUS error */
if (qc->err_mask & AC_ERR_ATA_BUS)
qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_MEDIA |
AC_ERR_INVALID);
/* any real error trumps unknown error */
if (qc->err_mask & ~AC_ERR_OTHER)
qc->err_mask &= ~AC_ERR_OTHER;
/* SENSE_VALID trumps dev/unknown error and revalidation */
if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
qc->err_mask &= ~(AC_ERR_DEV | AC_ERR_OTHER);
ehc->i.action &= ~ATA_EH_REVALIDATE;
}
/* accumulate error info */
ehc->i.dev = qc->dev;
all_err_mask |= qc->err_mask;
if (qc->flags & ATA_QCFLAG_IO)
is_io = 1;
}
/* enforce default EH actions */
if (ap->pflags & ATA_PFLAG_FROZEN ||
all_err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT))
ehc->i.action |= ATA_EH_SOFTRESET;
else if (all_err_mask)
ehc->i.action |= ATA_EH_REVALIDATE;
/* if we have offending qcs and the associated failed device */
if (ehc->i.dev) {
/* speed down */
ehc->i.action |= ata_eh_speed_down(ehc->i.dev, is_io,
all_err_mask);
/* perform per-dev EH action only on the offending device */
ehc->i.dev_action[ehc->i.dev->devno] |=
ehc->i.action & ATA_EH_PERDEV_MASK;
ehc->i.action &= ~ATA_EH_PERDEV_MASK;
}
DPRINTK("EXIT\n");
}
/**
* ata_eh_report - report error handling to user
* @ap: ATA port EH is going on
*
* Report EH to user.
*
* LOCKING:
* None.
*/
static void ata_eh_report(struct ata_port *ap)
{
struct ata_eh_context *ehc = &ap->eh_context;
const char *frozen, *desc;
int tag, nr_failed = 0;
desc = NULL;
if (ehc->i.desc[0] != '\0')
desc = ehc->i.desc;
for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
if (!(qc->flags & ATA_QCFLAG_FAILED))
continue;
if (qc->flags & ATA_QCFLAG_SENSE_VALID && !qc->err_mask)
continue;
nr_failed++;
}
if (!nr_failed && !ehc->i.err_mask)
return;
frozen = "";
if (ap->pflags & ATA_PFLAG_FROZEN)
frozen = " frozen";
if (ehc->i.dev) {
ata_dev_printk(ehc->i.dev, KERN_ERR, "exception Emask 0x%x "
"SAct 0x%x SErr 0x%x action 0x%x%s\n",
ehc->i.err_mask, ap->sactive, ehc->i.serror,
ehc->i.action, frozen);
if (desc)
ata_dev_printk(ehc->i.dev, KERN_ERR, "(%s)\n", desc);
} else {
ata_port_printk(ap, KERN_ERR, "exception Emask 0x%x "
"SAct 0x%x SErr 0x%x action 0x%x%s\n",
ehc->i.err_mask, ap->sactive, ehc->i.serror,
ehc->i.action, frozen);
if (desc)
ata_port_printk(ap, KERN_ERR, "(%s)\n", desc);
}
for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
static const char *dma_str[] = {
[DMA_BIDIRECTIONAL] = "bidi",
[DMA_TO_DEVICE] = "out",
[DMA_FROM_DEVICE] = "in",
[DMA_NONE] = "",
};
struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
struct ata_taskfile *cmd = &qc->tf, *res = &qc->result_tf;
unsigned int nbytes;
if (!(qc->flags & ATA_QCFLAG_FAILED) || !qc->err_mask)
continue;
nbytes = qc->nbytes;
if (!nbytes)
nbytes = qc->nsect << 9;
ata_dev_printk(qc->dev, KERN_ERR,
"cmd %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
"tag %d cdb 0x%x data %u %s\n "
"res %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
"Emask 0x%x (%s)\n",
cmd->command, cmd->feature, cmd->nsect,
cmd->lbal, cmd->lbam, cmd->lbah,
cmd->hob_feature, cmd->hob_nsect,
cmd->hob_lbal, cmd->hob_lbam, cmd->hob_lbah,
cmd->device, qc->tag, qc->cdb[0], nbytes,
dma_str[qc->dma_dir],
res->command, res->feature, res->nsect,
res->lbal, res->lbam, res->lbah,
res->hob_feature, res->hob_nsect,
res->hob_lbal, res->hob_lbam, res->hob_lbah,
res->device, qc->err_mask, ata_err_string(qc->err_mask));
}
}
static int ata_do_reset(struct ata_port *ap, ata_reset_fn_t reset,
unsigned int *classes)
{
int i, rc;
for (i = 0; i < ATA_MAX_DEVICES; i++)
classes[i] = ATA_DEV_UNKNOWN;
rc = reset(ap, classes);
if (rc)
return rc;
/* If any class isn't ATA_DEV_UNKNOWN, consider classification
* is complete and convert all ATA_DEV_UNKNOWN to
* ATA_DEV_NONE.
*/
for (i = 0; i < ATA_MAX_DEVICES; i++)
if (classes[i] != ATA_DEV_UNKNOWN)
break;
if (i < ATA_MAX_DEVICES)
for (i = 0; i < ATA_MAX_DEVICES; i++)
if (classes[i] == ATA_DEV_UNKNOWN)
classes[i] = ATA_DEV_NONE;
return 0;
}
static int ata_eh_followup_srst_needed(int rc, int classify,
const unsigned int *classes)
{
if (rc == -EAGAIN)
return 1;
if (rc != 0)
return 0;
if (classify && classes[0] == ATA_DEV_UNKNOWN)
return 1;
return 0;
}
static int ata_eh_reset(struct ata_port *ap, int classify,
ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
{
struct ata_eh_context *ehc = &ap->eh_context;
unsigned int *classes = ehc->classes;
int tries = ATA_EH_RESET_TRIES;
int verbose = !(ehc->i.flags & ATA_EHI_QUIET);
unsigned int action;
ata_reset_fn_t reset;
int i, did_followup_srst, rc;
/* about to reset */
ata_eh_about_to_do(ap, NULL, ehc->i.action & ATA_EH_RESET_MASK);
/* Determine which reset to use and record in ehc->i.action.
* prereset() may examine and modify it.
*/
action = ehc->i.action;
ehc->i.action &= ~ATA_EH_RESET_MASK;
if (softreset && (!hardreset || (!sata_set_spd_needed(ap) &&
!(action & ATA_EH_HARDRESET))))
ehc->i.action |= ATA_EH_SOFTRESET;
else
ehc->i.action |= ATA_EH_HARDRESET;
if (prereset) {
rc = prereset(ap);
if (rc) {
if (rc == -ENOENT) {
ata_port_printk(ap, KERN_DEBUG, "port disabled. ignoring.\n");
ap->eh_context.i.action &= ~ATA_EH_RESET_MASK;
} else
ata_port_printk(ap, KERN_ERR,
"prereset failed (errno=%d)\n", rc);
return rc;
}
}
/* prereset() might have modified ehc->i.action */
if (ehc->i.action & ATA_EH_HARDRESET)
reset = hardreset;
else if (ehc->i.action & ATA_EH_SOFTRESET)
reset = softreset;
else {
/* prereset told us not to reset, bang classes and return */
for (i = 0; i < ATA_MAX_DEVICES; i++)
classes[i] = ATA_DEV_NONE;
return 0;
}
/* did prereset() screw up? if so, fix up to avoid oopsing */
if (!reset) {
ata_port_printk(ap, KERN_ERR, "BUG: prereset() requested "
"invalid reset type\n");
if (softreset)
reset = softreset;
else
reset = hardreset;
}
retry:
/* shut up during boot probing */
if (verbose)
ata_port_printk(ap, KERN_INFO, "%s resetting port\n",
reset == softreset ? "soft" : "hard");
/* mark that this EH session started with reset */
ehc->i.flags |= ATA_EHI_DID_RESET;
rc = ata_do_reset(ap, reset, classes);
did_followup_srst = 0;
if (reset == hardreset &&
ata_eh_followup_srst_needed(rc, classify, classes)) {
/* okay, let's do follow-up softreset */
did_followup_srst = 1;
reset = softreset;
if (!reset) {
ata_port_printk(ap, KERN_ERR,
"follow-up softreset required "
"but no softreset avaliable\n");
return -EINVAL;
}
ata_eh_about_to_do(ap, NULL, ATA_EH_RESET_MASK);
rc = ata_do_reset(ap, reset, classes);
if (rc == 0 && classify &&
classes[0] == ATA_DEV_UNKNOWN) {
ata_port_printk(ap, KERN_ERR,
"classification failed\n");
return -EINVAL;
}
}
if (rc && --tries) {
const char *type;
if (reset == softreset) {
if (did_followup_srst)
type = "follow-up soft";
else
type = "soft";
} else
type = "hard";
ata_port_printk(ap, KERN_WARNING,
"%sreset failed, retrying in 5 secs\n", type);
ssleep(5);
if (reset == hardreset)
sata_down_spd_limit(ap);
if (hardreset)
reset = hardreset;
goto retry;
}
if (rc == 0) {
/* After the reset, the device state is PIO 0 and the
* controller state is undefined. Record the mode.
*/
for (i = 0; i < ATA_MAX_DEVICES; i++)
ap->device[i].pio_mode = XFER_PIO_0;
if (postreset)
postreset(ap, classes);
/* reset successful, schedule revalidation */
ata_eh_done(ap, NULL, ehc->i.action & ATA_EH_RESET_MASK);
ehc->i.action |= ATA_EH_REVALIDATE;
}
return rc;
}
static int ata_eh_revalidate_and_attach(struct ata_port *ap,
struct ata_device **r_failed_dev)
{
struct ata_eh_context *ehc = &ap->eh_context;
struct ata_device *dev;
unsigned long flags;
int i, rc = 0;
DPRINTK("ENTER\n");
for (i = 0; i < ATA_MAX_DEVICES; i++) {
unsigned int action, readid_flags = 0;
dev = &ap->device[i];
action = ata_eh_dev_action(dev);
if (ehc->i.flags & ATA_EHI_DID_RESET)
readid_flags |= ATA_READID_POSTRESET;
if (action & ATA_EH_REVALIDATE && ata_dev_ready(dev)) {
if (ata_port_offline(ap)) {
rc = -EIO;
break;
}
ata_eh_about_to_do(ap, dev, ATA_EH_REVALIDATE);
rc = ata_dev_revalidate(dev, readid_flags);
if (rc)
break;
ata_eh_done(ap, dev, ATA_EH_REVALIDATE);
/* Configuration may have changed, reconfigure
* transfer mode.
*/
ehc->i.flags |= ATA_EHI_SETMODE;
/* schedule the scsi_rescan_device() here */
queue_work(ata_aux_wq, &(ap->scsi_rescan_task));
} else if (dev->class == ATA_DEV_UNKNOWN &&
ehc->tries[dev->devno] &&
ata_class_enabled(ehc->classes[dev->devno])) {
dev->class = ehc->classes[dev->devno];
rc = ata_dev_read_id(dev, &dev->class, readid_flags,
dev->id);
if (rc == 0) {
ehc->i.flags |= ATA_EHI_PRINTINFO;
rc = ata_dev_configure(dev);
ehc->i.flags &= ~ATA_EHI_PRINTINFO;
} else if (rc == -ENOENT) {
/* IDENTIFY was issued to non-existent
* device. No need to reset. Just
* thaw and kill the device.
*/
ata_eh_thaw_port(ap);
dev->class = ATA_DEV_UNKNOWN;
rc = 0;
}
if (rc) {
dev->class = ATA_DEV_UNKNOWN;
break;
}
if (ata_dev_enabled(dev)) {
spin_lock_irqsave(ap->lock, flags);
ap->pflags |= ATA_PFLAG_SCSI_HOTPLUG;
spin_unlock_irqrestore(ap->lock, flags);
/* new device discovered, configure xfermode */
ehc->i.flags |= ATA_EHI_SETMODE;
}
}
}
if (rc)
*r_failed_dev = dev;
DPRINTK("EXIT\n");
return rc;
}
/**
* ata_eh_suspend - handle suspend EH action
* @ap: target host port
* @r_failed_dev: result parameter to indicate failing device
*
* Handle suspend EH action. Disk devices are spinned down and
* other types of devices are just marked suspended. Once
* suspended, no EH action to the device is allowed until it is
* resumed.
*
* LOCKING:
* Kernel thread context (may sleep).
*
* RETURNS:
* 0 on success, -errno otherwise
*/
static int ata_eh_suspend(struct ata_port *ap, struct ata_device **r_failed_dev)
{
struct ata_device *dev;
int i, rc = 0;
DPRINTK("ENTER\n");
for (i = 0; i < ATA_MAX_DEVICES; i++) {
unsigned long flags;
unsigned int action, err_mask;
dev = &ap->device[i];
action = ata_eh_dev_action(dev);
if (!ata_dev_enabled(dev) || !(action & ATA_EH_SUSPEND))
continue;
WARN_ON(dev->flags & ATA_DFLAG_SUSPENDED);
ata_eh_about_to_do(ap, dev, ATA_EH_SUSPEND);
if (dev->class == ATA_DEV_ATA && !(action & ATA_EH_PM_FREEZE)) {
/* flush cache */
rc = ata_flush_cache(dev);
if (rc)
break;
/* spin down */
err_mask = ata_do_simple_cmd(dev, ATA_CMD_STANDBYNOW1);
if (err_mask) {
ata_dev_printk(dev, KERN_ERR, "failed to "
"spin down (err_mask=0x%x)\n",
err_mask);
rc = -EIO;
break;
}
}
spin_lock_irqsave(ap->lock, flags);
dev->flags |= ATA_DFLAG_SUSPENDED;
spin_unlock_irqrestore(ap->lock, flags);
ata_eh_done(ap, dev, ATA_EH_SUSPEND);
}
if (rc)
*r_failed_dev = dev;
DPRINTK("EXIT\n");
return 0;
}
/**
* ata_eh_prep_resume - prep for resume EH action
* @ap: target host port
*
* Clear SUSPENDED in preparation for scheduled resume actions.
* This allows other parts of EH to access the devices being
* resumed.
*
* LOCKING:
* Kernel thread context (may sleep).
*/
static void ata_eh_prep_resume(struct ata_port *ap)
{
struct ata_device *dev;
unsigned long flags;
int i;
DPRINTK("ENTER\n");
for (i = 0; i < ATA_MAX_DEVICES; i++) {
unsigned int action;
dev = &ap->device[i];
action = ata_eh_dev_action(dev);
if (!ata_dev_enabled(dev) || !(action & ATA_EH_RESUME))
continue;
spin_lock_irqsave(ap->lock, flags);
dev->flags &= ~ATA_DFLAG_SUSPENDED;
spin_unlock_irqrestore(ap->lock, flags);
}
DPRINTK("EXIT\n");
}
/**
* ata_eh_resume - handle resume EH action
* @ap: target host port
* @r_failed_dev: result parameter to indicate failing device
*
* Handle resume EH action. Target devices are already reset and
* revalidated. Spinning up is the only operation left.
*
* LOCKING:
* Kernel thread context (may sleep).
*
* RETURNS:
* 0 on success, -errno otherwise
*/
static int ata_eh_resume(struct ata_port *ap, struct ata_device **r_failed_dev)
{
struct ata_device *dev;
int i, rc = 0;
DPRINTK("ENTER\n");
for (i = 0; i < ATA_MAX_DEVICES; i++) {
unsigned int action, err_mask;
dev = &ap->device[i];
action = ata_eh_dev_action(dev);
if (!ata_dev_enabled(dev) || !(action & ATA_EH_RESUME))
continue;
ata_eh_about_to_do(ap, dev, ATA_EH_RESUME);
if (dev->class == ATA_DEV_ATA && !(action & ATA_EH_PM_FREEZE)) {
err_mask = ata_do_simple_cmd(dev,
ATA_CMD_IDLEIMMEDIATE);
if (err_mask) {
ata_dev_printk(dev, KERN_ERR, "failed to "
"spin up (err_mask=0x%x)\n",
err_mask);
rc = -EIO;
break;
}
}
ata_eh_done(ap, dev, ATA_EH_RESUME);
}
if (rc)
*r_failed_dev = dev;
DPRINTK("EXIT\n");
return 0;
}
static int ata_port_nr_enabled(struct ata_port *ap)
{
int i, cnt = 0;
for (i = 0; i < ATA_MAX_DEVICES; i++)
if (ata_dev_enabled(&ap->device[i]))
cnt++;
return cnt;
}
static int ata_port_nr_vacant(struct ata_port *ap)
{
int i, cnt = 0;
for (i = 0; i < ATA_MAX_DEVICES; i++)
if (ap->device[i].class == ATA_DEV_UNKNOWN)
cnt++;
return cnt;
}
static int ata_eh_skip_recovery(struct ata_port *ap)
{
struct ata_eh_context *ehc = &ap->eh_context;
int i;
/* skip if all possible devices are suspended */
for (i = 0; i < ata_port_max_devices(ap); i++) {
struct ata_device *dev = &ap->device[i];
if (!(dev->flags & ATA_DFLAG_SUSPENDED))
break;
}
if (i == ata_port_max_devices(ap))
return 1;
/* thaw frozen port, resume link and recover failed devices */
if ((ap->pflags & ATA_PFLAG_FROZEN) ||
(ehc->i.flags & ATA_EHI_RESUME_LINK) || ata_port_nr_enabled(ap))
return 0;
/* skip if class codes for all vacant slots are ATA_DEV_NONE */
for (i = 0; i < ATA_MAX_DEVICES; i++) {
struct ata_device *dev = &ap->device[i];
if (dev->class == ATA_DEV_UNKNOWN &&
ehc->classes[dev->devno] != ATA_DEV_NONE)
return 0;
}
return 1;
}
/**
* ata_eh_recover - recover host port after error
* @ap: host port to recover
* @prereset: prereset method (can be NULL)
* @softreset: softreset method (can be NULL)
* @hardreset: hardreset method (can be NULL)
* @postreset: postreset method (can be NULL)
*
* This is the alpha and omega, eum and yang, heart and soul of
* libata exception handling. On entry, actions required to
* recover the port and hotplug requests are recorded in
* eh_context. This function executes all the operations with
* appropriate retrials and fallbacks to resurrect failed
* devices, detach goners and greet newcomers.
*
* LOCKING:
* Kernel thread context (may sleep).
*
* RETURNS:
* 0 on success, -errno on failure.
*/
static int ata_eh_recover(struct ata_port *ap, ata_prereset_fn_t prereset,
ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
ata_postreset_fn_t postreset)
{
struct ata_eh_context *ehc = &ap->eh_context;
struct ata_device *dev;
int down_xfermask, i, rc;
DPRINTK("ENTER\n");
/* prep for recovery */
for (i = 0; i < ATA_MAX_DEVICES; i++) {
dev = &ap->device[i];
ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
/* collect port action mask recorded in dev actions */
ehc->i.action |= ehc->i.dev_action[i] & ~ATA_EH_PERDEV_MASK;
ehc->i.dev_action[i] &= ATA_EH_PERDEV_MASK;
/* process hotplug request */
if (dev->flags & ATA_DFLAG_DETACH)
ata_eh_detach_dev(dev);
if (!ata_dev_enabled(dev) &&
((ehc->i.probe_mask & (1 << dev->devno)) &&
!(ehc->did_probe_mask & (1 << dev->devno)))) {
ata_eh_detach_dev(dev);
ata_dev_init(dev);
ehc->did_probe_mask |= (1 << dev->devno);
ehc->i.action |= ATA_EH_SOFTRESET;
}
}
retry:
down_xfermask = 0;
rc = 0;
/* if UNLOADING, finish immediately */
if (ap->pflags & ATA_PFLAG_UNLOADING)
goto out;
/* prep for resume */
ata_eh_prep_resume(ap);
/* skip EH if possible. */
if (ata_eh_skip_recovery(ap))
ehc->i.action = 0;
for (i = 0; i < ATA_MAX_DEVICES; i++)
ehc->classes[i] = ATA_DEV_UNKNOWN;
/* reset */
if (ehc->i.action & ATA_EH_RESET_MASK) {
ata_eh_freeze_port(ap);
rc = ata_eh_reset(ap, ata_port_nr_vacant(ap), prereset,
softreset, hardreset, postreset);
if (rc) {
ata_port_printk(ap, KERN_ERR,
"reset failed, giving up\n");
goto out;
}
ata_eh_thaw_port(ap);
}
/* revalidate existing devices and attach new ones */
rc = ata_eh_revalidate_and_attach(ap, &dev);
if (rc)
goto dev_fail;
/* resume devices */
rc = ata_eh_resume(ap, &dev);
if (rc)
goto dev_fail;
/* configure transfer mode if necessary */
if (ehc->i.flags & ATA_EHI_SETMODE) {
rc = ata_set_mode(ap, &dev);
if (rc) {
down_xfermask = 1;
goto dev_fail;
}
ehc->i.flags &= ~ATA_EHI_SETMODE;
}
/* suspend devices */
rc = ata_eh_suspend(ap, &dev);
if (rc)
goto dev_fail;
goto out;
dev_fail:
switch (rc) {
case -ENODEV:
/* device missing, schedule probing */
ehc->i.probe_mask |= (1 << dev->devno);
case -EINVAL:
ehc->tries[dev->devno] = 0;
break;
case -EIO:
sata_down_spd_limit(ap);
default:
ehc->tries[dev->devno]--;
if (down_xfermask &&
ata_down_xfermask_limit(dev, ehc->tries[dev->devno] == 1))
ehc->tries[dev->devno] = 0;
}
if (ata_dev_enabled(dev) && !ehc->tries[dev->devno]) {
/* disable device if it has used up all its chances */
ata_dev_disable(dev);
/* detach if offline */
if (ata_port_offline(ap))
ata_eh_detach_dev(dev);
/* probe if requested */
if ((ehc->i.probe_mask & (1 << dev->devno)) &&
!(ehc->did_probe_mask & (1 << dev->devno))) {
ata_eh_detach_dev(dev);
ata_dev_init(dev);
ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
ehc->did_probe_mask |= (1 << dev->devno);
ehc->i.action |= ATA_EH_SOFTRESET;
}
} else {
/* soft didn't work? be haaaaard */
if (ehc->i.flags & ATA_EHI_DID_RESET)
ehc->i.action |= ATA_EH_HARDRESET;
else
ehc->i.action |= ATA_EH_SOFTRESET;
}
if (ata_port_nr_enabled(ap)) {
ata_port_printk(ap, KERN_WARNING, "failed to recover some "
"devices, retrying in 5 secs\n");
ssleep(5);
} else {
/* no device left, repeat fast */
msleep(500);
}
goto retry;
out:
if (rc) {
for (i = 0; i < ATA_MAX_DEVICES; i++)
ata_dev_disable(&ap->device[i]);
}
DPRINTK("EXIT, rc=%d\n", rc);
return rc;
}
/**
* ata_eh_finish - finish up EH
* @ap: host port to finish EH for
*
* Recovery is complete. Clean up EH states and retry or finish
* failed qcs.
*
* LOCKING:
* None.
*/
static void ata_eh_finish(struct ata_port *ap)
{
int tag;
/* retry or finish qcs */
for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
if (!(qc->flags & ATA_QCFLAG_FAILED))
continue;
if (qc->err_mask) {
/* FIXME: Once EH migration is complete,
* generate sense data in this function,
* considering both err_mask and tf.
*/
if (qc->err_mask & AC_ERR_INVALID)
ata_eh_qc_complete(qc);
else
ata_eh_qc_retry(qc);
} else {
if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
ata_eh_qc_complete(qc);
} else {
/* feed zero TF to sense generation */
memset(&qc->result_tf, 0, sizeof(qc->result_tf));
ata_eh_qc_retry(qc);
}
}
}
}
/**
* ata_do_eh - do standard error handling
* @ap: host port to handle error for
* @prereset: prereset method (can be NULL)
* @softreset: softreset method (can be NULL)
* @hardreset: hardreset method (can be NULL)
* @postreset: postreset method (can be NULL)
*
* Perform standard error handling sequence.
*
* LOCKING:
* Kernel thread context (may sleep).
*/
void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
ata_postreset_fn_t postreset)
{
ata_eh_autopsy(ap);
ata_eh_report(ap);
ata_eh_recover(ap, prereset, softreset, hardreset, postreset);
ata_eh_finish(ap);
}
/**
* ata_eh_handle_port_suspend - perform port suspend operation
* @ap: port to suspend
*
* Suspend @ap.
*
* LOCKING:
* Kernel thread context (may sleep).
*/
static void ata_eh_handle_port_suspend(struct ata_port *ap)
{
unsigned long flags;
int rc = 0;
/* are we suspending? */
spin_lock_irqsave(ap->lock, flags);
if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
ap->pm_mesg.event == PM_EVENT_ON) {
spin_unlock_irqrestore(ap->lock, flags);
return;
}
spin_unlock_irqrestore(ap->lock, flags);
WARN_ON(ap->pflags & ATA_PFLAG_SUSPENDED);
/* suspend */
ata_eh_freeze_port(ap);
if (ap->ops->port_suspend)
rc = ap->ops->port_suspend(ap, ap->pm_mesg);
/* report result */
spin_lock_irqsave(ap->lock, flags);
ap->pflags &= ~ATA_PFLAG_PM_PENDING;
if (rc == 0)
ap->pflags |= ATA_PFLAG_SUSPENDED;
else
ata_port_schedule_eh(ap);
if (ap->pm_result) {
*ap->pm_result = rc;
ap->pm_result = NULL;
}
spin_unlock_irqrestore(ap->lock, flags);
return;
}
/**
* ata_eh_handle_port_resume - perform port resume operation
* @ap: port to resume
*
* Resume @ap.
*
* This function also waits upto one second until all devices
* hanging off this port requests resume EH action. This is to
* prevent invoking EH and thus reset multiple times on resume.
*
* On DPM resume, where some of devices might not be resumed
* together, this may delay port resume upto one second, but such
* DPM resumes are rare and 1 sec delay isn't too bad.
*
* LOCKING:
* Kernel thread context (may sleep).
*/
static void ata_eh_handle_port_resume(struct ata_port *ap)
{
unsigned long timeout;
unsigned long flags;
int i, rc = 0;
/* are we resuming? */
spin_lock_irqsave(ap->lock, flags);
if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
ap->pm_mesg.event != PM_EVENT_ON) {
spin_unlock_irqrestore(ap->lock, flags);
return;
}
spin_unlock_irqrestore(ap->lock, flags);
/* spurious? */
if (!(ap->pflags & ATA_PFLAG_SUSPENDED))
goto done;
if (ap->ops->port_resume)
rc = ap->ops->port_resume(ap);
/* give devices time to request EH */
timeout = jiffies + HZ; /* 1s max */
while (1) {
for (i = 0; i < ATA_MAX_DEVICES; i++) {
struct ata_device *dev = &ap->device[i];
unsigned int action = ata_eh_dev_action(dev);
if ((dev->flags & ATA_DFLAG_SUSPENDED) &&
!(action & ATA_EH_RESUME))
break;
}
if (i == ATA_MAX_DEVICES || time_after(jiffies, timeout))
break;
msleep(10);
}
done:
spin_lock_irqsave(ap->lock, flags);
ap->pflags &= ~(ATA_PFLAG_PM_PENDING | ATA_PFLAG_SUSPENDED);
if (ap->pm_result) {
*ap->pm_result = rc;
ap->pm_result = NULL;
}
spin_unlock_irqrestore(ap->lock, flags);
}
