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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/ata/libata-eh.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/ata/libata-eh.c')
-rw-r--r--kernel/drivers/ata/libata-eh.c4251
1 files changed, 4251 insertions, 0 deletions
diff --git a/kernel/drivers/ata/libata-eh.c b/kernel/drivers/ata/libata-eh.c
new file mode 100644
index 000000000..cf0022ec0
--- /dev/null
+++ b/kernel/drivers/ata/libata-eh.c
@@ -0,0 +1,4251 @@
+/*
+ * libata-eh.c - libata error handling
+ *
+ * Maintained by: Tejun Heo <tj@kernel.org>
+ * 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 <linux/blkdev.h>
+#include <linux/export.h>
+#include <linux/pci.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_dbg.h>
+#include "../scsi/scsi_transport_api.h"
+
+#include <linux/libata.h>
+
+#include <trace/events/libata.h>
+#include "libata.h"
+
+enum {
+ /* speed down verdicts */
+ ATA_EH_SPDN_NCQ_OFF = (1 << 0),
+ ATA_EH_SPDN_SPEED_DOWN = (1 << 1),
+ ATA_EH_SPDN_FALLBACK_TO_PIO = (1 << 2),
+ ATA_EH_SPDN_KEEP_ERRORS = (1 << 3),
+
+ /* error flags */
+ ATA_EFLAG_IS_IO = (1 << 0),
+ ATA_EFLAG_DUBIOUS_XFER = (1 << 1),
+ ATA_EFLAG_OLD_ER = (1 << 31),
+
+ /* error categories */
+ ATA_ECAT_NONE = 0,
+ ATA_ECAT_ATA_BUS = 1,
+ ATA_ECAT_TOUT_HSM = 2,
+ ATA_ECAT_UNK_DEV = 3,
+ ATA_ECAT_DUBIOUS_NONE = 4,
+ ATA_ECAT_DUBIOUS_ATA_BUS = 5,
+ ATA_ECAT_DUBIOUS_TOUT_HSM = 6,
+ ATA_ECAT_DUBIOUS_UNK_DEV = 7,
+ ATA_ECAT_NR = 8,
+
+ ATA_EH_CMD_DFL_TIMEOUT = 5000,
+
+ /* always put at least this amount of time between resets */
+ ATA_EH_RESET_COOL_DOWN = 5000,
+
+ /* Waiting in ->prereset can never be reliable. It's
+ * sometimes nice to wait there but it can't be depended upon;
+ * otherwise, we wouldn't be resetting. Just give it enough
+ * time for most drives to spin up.
+ */
+ ATA_EH_PRERESET_TIMEOUT = 10000,
+ ATA_EH_FASTDRAIN_INTERVAL = 3000,
+
+ ATA_EH_UA_TRIES = 5,
+
+ /* probe speed down parameters, see ata_eh_schedule_probe() */
+ ATA_EH_PROBE_TRIAL_INTERVAL = 60000, /* 1 min */
+ ATA_EH_PROBE_TRIALS = 2,
+};
+
+/* The following table determines how we sequence resets. Each entry
+ * represents timeout for that try. The first try can be soft or
+ * hardreset. All others are hardreset if available. In most cases
+ * the first reset w/ 10sec timeout should succeed. Following entries
+ * are mostly for error handling, hotplug and those outlier devices that
+ * take an exceptionally long time to recover from reset.
+ */
+static const unsigned long ata_eh_reset_timeouts[] = {
+ 10000, /* most drives spin up by 10sec */
+ 10000, /* > 99% working drives spin up before 20sec */
+ 35000, /* give > 30 secs of idleness for outlier devices */
+ 5000, /* and sweet one last chance */
+ ULONG_MAX, /* > 1 min has elapsed, give up */
+};
+
+static const unsigned long ata_eh_identify_timeouts[] = {
+ 5000, /* covers > 99% of successes and not too boring on failures */
+ 10000, /* combined time till here is enough even for media access */
+ 30000, /* for true idiots */
+ ULONG_MAX,
+};
+
+static const unsigned long ata_eh_flush_timeouts[] = {
+ 15000, /* be generous with flush */
+ 15000, /* ditto */
+ 30000, /* and even more generous */
+ ULONG_MAX,
+};
+
+static const unsigned long ata_eh_other_timeouts[] = {
+ 5000, /* same rationale as identify timeout */
+ 10000, /* ditto */
+ /* but no merciful 30sec for other commands, it just isn't worth it */
+ ULONG_MAX,
+};
+
+struct ata_eh_cmd_timeout_ent {
+ const u8 *commands;
+ const unsigned long *timeouts;
+};
+
+/* The following table determines timeouts to use for EH internal
+ * commands. Each table entry is a command class and matches the
+ * commands the entry applies to and the timeout table to use.
+ *
+ * On the retry after a command timed out, the next timeout value from
+ * the table is used. If the table doesn't contain further entries,
+ * the last value is used.
+ *
+ * ehc->cmd_timeout_idx keeps track of which timeout to use per
+ * command class, so if SET_FEATURES times out on the first try, the
+ * next try will use the second timeout value only for that class.
+ */
+#define CMDS(cmds...) (const u8 []){ cmds, 0 }
+static const struct ata_eh_cmd_timeout_ent
+ata_eh_cmd_timeout_table[ATA_EH_CMD_TIMEOUT_TABLE_SIZE] = {
+ { .commands = CMDS(ATA_CMD_ID_ATA, ATA_CMD_ID_ATAPI),
+ .timeouts = ata_eh_identify_timeouts, },
+ { .commands = CMDS(ATA_CMD_READ_NATIVE_MAX, ATA_CMD_READ_NATIVE_MAX_EXT),
+ .timeouts = ata_eh_other_timeouts, },
+ { .commands = CMDS(ATA_CMD_SET_MAX, ATA_CMD_SET_MAX_EXT),
+ .timeouts = ata_eh_other_timeouts, },
+ { .commands = CMDS(ATA_CMD_SET_FEATURES),
+ .timeouts = ata_eh_other_timeouts, },
+ { .commands = CMDS(ATA_CMD_INIT_DEV_PARAMS),
+ .timeouts = ata_eh_other_timeouts, },
+ { .commands = CMDS(ATA_CMD_FLUSH, ATA_CMD_FLUSH_EXT),
+ .timeouts = ata_eh_flush_timeouts },
+};
+#undef CMDS
+
+static void __ata_port_freeze(struct ata_port *ap);
+#ifdef CONFIG_PM
+static void ata_eh_handle_port_suspend(struct ata_port *ap);
+static void ata_eh_handle_port_resume(struct ata_port *ap);
+#else /* CONFIG_PM */
+static void ata_eh_handle_port_suspend(struct ata_port *ap)
+{ }
+
+static void ata_eh_handle_port_resume(struct ata_port *ap)
+{ }
+#endif /* CONFIG_PM */
+
+static void __ata_ehi_pushv_desc(struct ata_eh_info *ehi, const char *fmt,
+ va_list args)
+{
+ ehi->desc_len += vscnprintf(ehi->desc + ehi->desc_len,
+ ATA_EH_DESC_LEN - ehi->desc_len,
+ fmt, args);
+}
+
+/**
+ * __ata_ehi_push_desc - push error description without adding separator
+ * @ehi: target EHI
+ * @fmt: printf format string
+ *
+ * Format string according to @fmt and append it to @ehi->desc.
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ */
+void __ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
+{
+ va_list args;
+
+ va_start(args, fmt);
+ __ata_ehi_pushv_desc(ehi, fmt, args);
+ va_end(args);
+}
+
+/**
+ * ata_ehi_push_desc - push error description with separator
+ * @ehi: target EHI
+ * @fmt: printf format string
+ *
+ * Format string according to @fmt and append it to @ehi->desc.
+ * If @ehi->desc is not empty, ", " is added in-between.
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ */
+void ata_ehi_push_desc(struct ata_eh_info *ehi, const char *fmt, ...)
+{
+ va_list args;
+
+ if (ehi->desc_len)
+ __ata_ehi_push_desc(ehi, ", ");
+
+ va_start(args, fmt);
+ __ata_ehi_pushv_desc(ehi, fmt, args);
+ va_end(args);
+}
+
+/**
+ * ata_ehi_clear_desc - clean error description
+ * @ehi: target EHI
+ *
+ * Clear @ehi->desc.
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ */
+void ata_ehi_clear_desc(struct ata_eh_info *ehi)
+{
+ ehi->desc[0] = '\0';
+ ehi->desc_len = 0;
+}
+
+/**
+ * ata_port_desc - append port description
+ * @ap: target ATA port
+ * @fmt: printf format string
+ *
+ * Format string according to @fmt and append it to port
+ * description. If port description is not empty, " " is added
+ * in-between. This function is to be used while initializing
+ * ata_host. The description is printed on host registration.
+ *
+ * LOCKING:
+ * None.
+ */
+void ata_port_desc(struct ata_port *ap, const char *fmt, ...)
+{
+ va_list args;
+
+ WARN_ON(!(ap->pflags & ATA_PFLAG_INITIALIZING));
+
+ if (ap->link.eh_info.desc_len)
+ __ata_ehi_push_desc(&ap->link.eh_info, " ");
+
+ va_start(args, fmt);
+ __ata_ehi_pushv_desc(&ap->link.eh_info, fmt, args);
+ va_end(args);
+}
+
+#ifdef CONFIG_PCI
+
+/**
+ * ata_port_pbar_desc - append PCI BAR description
+ * @ap: target ATA port
+ * @bar: target PCI BAR
+ * @offset: offset into PCI BAR
+ * @name: name of the area
+ *
+ * If @offset is negative, this function formats a string which
+ * contains the name, address, size and type of the BAR and
+ * appends it to the port description. If @offset is zero or
+ * positive, only name and offsetted address is appended.
+ *
+ * LOCKING:
+ * None.
+ */
+void ata_port_pbar_desc(struct ata_port *ap, int bar, ssize_t offset,
+ const char *name)
+{
+ struct pci_dev *pdev = to_pci_dev(ap->host->dev);
+ char *type = "";
+ unsigned long long start, len;
+
+ if (pci_resource_flags(pdev, bar) & IORESOURCE_MEM)
+ type = "m";
+ else if (pci_resource_flags(pdev, bar) & IORESOURCE_IO)
+ type = "i";
+
+ start = (unsigned long long)pci_resource_start(pdev, bar);
+ len = (unsigned long long)pci_resource_len(pdev, bar);
+
+ if (offset < 0)
+ ata_port_desc(ap, "%s %s%llu@0x%llx", name, type, len, start);
+ else
+ ata_port_desc(ap, "%s 0x%llx", name,
+ start + (unsigned long long)offset);
+}
+
+#endif /* CONFIG_PCI */
+
+static int ata_lookup_timeout_table(u8 cmd)
+{
+ int i;
+
+ for (i = 0; i < ATA_EH_CMD_TIMEOUT_TABLE_SIZE; i++) {
+ const u8 *cur;
+
+ for (cur = ata_eh_cmd_timeout_table[i].commands; *cur; cur++)
+ if (*cur == cmd)
+ return i;
+ }
+
+ return -1;
+}
+
+/**
+ * ata_internal_cmd_timeout - determine timeout for an internal command
+ * @dev: target device
+ * @cmd: internal command to be issued
+ *
+ * Determine timeout for internal command @cmd for @dev.
+ *
+ * LOCKING:
+ * EH context.
+ *
+ * RETURNS:
+ * Determined timeout.
+ */
+unsigned long ata_internal_cmd_timeout(struct ata_device *dev, u8 cmd)
+{
+ struct ata_eh_context *ehc = &dev->link->eh_context;
+ int ent = ata_lookup_timeout_table(cmd);
+ int idx;
+
+ if (ent < 0)
+ return ATA_EH_CMD_DFL_TIMEOUT;
+
+ idx = ehc->cmd_timeout_idx[dev->devno][ent];
+ return ata_eh_cmd_timeout_table[ent].timeouts[idx];
+}
+
+/**
+ * ata_internal_cmd_timed_out - notification for internal command timeout
+ * @dev: target device
+ * @cmd: internal command which timed out
+ *
+ * Notify EH that internal command @cmd for @dev timed out. This
+ * function should be called only for commands whose timeouts are
+ * determined using ata_internal_cmd_timeout().
+ *
+ * LOCKING:
+ * EH context.
+ */
+void ata_internal_cmd_timed_out(struct ata_device *dev, u8 cmd)
+{
+ struct ata_eh_context *ehc = &dev->link->eh_context;
+ int ent = ata_lookup_timeout_table(cmd);
+ int idx;
+
+ if (ent < 0)
+ return;
+
+ idx = ehc->cmd_timeout_idx[dev->devno][ent];
+ if (ata_eh_cmd_timeout_table[ent].timeouts[idx + 1] != ULONG_MAX)
+ ehc->cmd_timeout_idx[dev->devno][ent]++;
+}
+
+static void ata_ering_record(struct ata_ering *ering, unsigned int eflags,
+ 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->eflags = eflags;
+ 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 ent;
+ return NULL;
+}
+
+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 int ata_ering_clear_cb(struct ata_ering_entry *ent, void *void_arg)
+{
+ ent->eflags |= ATA_EFLAG_OLD_ER;
+ return 0;
+}
+
+static void ata_ering_clear(struct ata_ering *ering)
+{
+ ata_ering_map(ering, ata_ering_clear_cb, NULL);
+}
+
+static unsigned int ata_eh_dev_action(struct ata_device *dev)
+{
+ struct ata_eh_context *ehc = &dev->link->eh_context;
+
+ return ehc->i.action | ehc->i.dev_action[dev->devno];
+}
+
+static void ata_eh_clear_action(struct ata_link *link, struct ata_device *dev,
+ struct ata_eh_info *ehi, unsigned int action)
+{
+ struct ata_device *tdev;
+
+ if (!dev) {
+ ehi->action &= ~action;
+ ata_for_each_dev(tdev, link, ALL)
+ ehi->dev_action[tdev->devno] &= ~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) {
+ ata_for_each_dev(tdev, link, ALL)
+ ehi->dev_action[tdev->devno] |=
+ ehi->action & action;
+ ehi->action &= ~action;
+ }
+
+ /* turn off the specified per-dev action */
+ ehi->dev_action[dev->devno] &= ~action;
+ }
+}
+
+/**
+ * ata_eh_acquire - acquire EH ownership
+ * @ap: ATA port to acquire EH ownership for
+ *
+ * Acquire EH ownership for @ap. This is the basic exclusion
+ * mechanism for ports sharing a host. Only one port hanging off
+ * the same host can claim the ownership of EH.
+ *
+ * LOCKING:
+ * EH context.
+ */
+void ata_eh_acquire(struct ata_port *ap)
+{
+ mutex_lock(&ap->host->eh_mutex);
+ WARN_ON_ONCE(ap->host->eh_owner);
+ ap->host->eh_owner = current;
+}
+
+/**
+ * ata_eh_release - release EH ownership
+ * @ap: ATA port to release EH ownership for
+ *
+ * Release EH ownership for @ap if the caller. The caller must
+ * have acquired EH ownership using ata_eh_acquire() previously.
+ *
+ * LOCKING:
+ * EH context.
+ */
+void ata_eh_release(struct ata_port *ap)
+{
+ WARN_ON_ONCE(ap->host->eh_owner != current);
+ ap->host->eh_owner = NULL;
+ mutex_unlock(&ap->host->eh_mutex);
+}
+
+/**
+ * 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 blk_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 blk_eh_timer_return ret;
+
+ DPRINTK("ENTER\n");
+
+ if (ap->ops->error_handler) {
+ ret = BLK_EH_NOT_HANDLED;
+ goto out;
+ }
+
+ ret = BLK_EH_HANDLED;
+ spin_lock_irqsave(ap->lock, flags);
+ qc = ata_qc_from_tag(ap, ap->link.active_tag);
+ if (qc) {
+ WARN_ON(qc->scsicmd != cmd);
+ qc->flags |= ATA_QCFLAG_EH_SCHEDULED;
+ qc->err_mask |= AC_ERR_TIMEOUT;
+ ret = BLK_EH_NOT_HANDLED;
+ }
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ out:
+ DPRINTK("EXIT, ret=%d\n", ret);
+ return ret;
+}
+
+static void ata_eh_unload(struct ata_port *ap)
+{
+ struct ata_link *link;
+ struct ata_device *dev;
+ unsigned long flags;
+
+ /* Restore SControl IPM and SPD for the next driver and
+ * disable attached devices.
+ */
+ ata_for_each_link(link, ap, PMP_FIRST) {
+ sata_scr_write(link, SCR_CONTROL, link->saved_scontrol & 0xff0);
+ ata_for_each_dev(dev, link, ALL)
+ ata_dev_disable(dev);
+ }
+
+ /* freeze and set UNLOADED */
+ spin_lock_irqsave(ap->lock, flags);
+
+ ata_port_freeze(ap); /* won't be thawed */
+ ap->pflags &= ~ATA_PFLAG_EH_PENDING; /* clear pending from freeze */
+ ap->pflags |= ATA_PFLAG_UNLOADED;
+
+ spin_unlock_irqrestore(ap->lock, flags);
+}
+
+/**
+ * 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);
+ unsigned long flags;
+ LIST_HEAD(eh_work_q);
+
+ DPRINTK("ENTER\n");
+
+ spin_lock_irqsave(host->host_lock, flags);
+ list_splice_init(&host->eh_cmd_q, &eh_work_q);
+ spin_unlock_irqrestore(host->host_lock, flags);
+
+ ata_scsi_cmd_error_handler(host, ap, &eh_work_q);
+
+ /* If we timed raced normal completion and there is nothing to
+ recover nr_timedout == 0 why exactly are we doing error recovery ? */
+ ata_scsi_port_error_handler(host, ap);
+
+ /* finish or retry handled scmd's and clean up */
+ WARN_ON(host->host_failed || !list_empty(&eh_work_q));
+
+ DPRINTK("EXIT\n");
+}
+
+/**
+ * ata_scsi_cmd_error_handler - error callback for a list of commands
+ * @host: scsi host containing the port
+ * @ap: ATA port within the host
+ * @eh_work_q: list of commands to process
+ *
+ * process the given list of commands and return those finished to the
+ * ap->eh_done_q. This function is the first part of the libata error
+ * handler which processes a given list of failed commands.
+ */
+void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
+ struct list_head *eh_work_q)
+{
+ int i;
+ unsigned long flags;
+
+ /* make sure sff pio task is not running */
+ ata_sff_flush_pio_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 completions 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);
+
+ /* This must occur under the ap->lock as we don't want
+ a polled recovery to race the real interrupt handler
+
+ The lost_interrupt handler checks for any completed but
+ non-notified command and completes much like an IRQ handler.
+
+ We then fall into the error recovery code which will treat
+ this as if normal completion won the race */
+
+ if (ap->ops->lost_interrupt)
+ ap->ops->lost_interrupt(ap);
+
+ list_for_each_entry_safe(scmd, tmp, eh_work_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);
+
+ /* initialize eh_tries */
+ ap->eh_tries = ATA_EH_MAX_TRIES;
+ } else
+ spin_unlock_wait(ap->lock);
+
+}
+EXPORT_SYMBOL(ata_scsi_cmd_error_handler);
+
+/**
+ * ata_scsi_port_error_handler - recover the port after the commands
+ * @host: SCSI host containing the port
+ * @ap: the ATA port
+ *
+ * Handle the recovery of the port @ap after all the commands
+ * have been recovered.
+ */
+void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap)
+{
+ unsigned long flags;
+
+ /* invoke error handler */
+ if (ap->ops->error_handler) {
+ struct ata_link *link;
+
+ /* acquire EH ownership */
+ ata_eh_acquire(ap);
+ repeat:
+ /* kill fast drain timer */
+ del_timer_sync(&ap->fastdrain_timer);
+
+ /* process port resume request */
+ ata_eh_handle_port_resume(ap);
+
+ /* fetch & clear EH info */
+ spin_lock_irqsave(ap->lock, flags);
+
+ ata_for_each_link(link, ap, HOST_FIRST) {
+ struct ata_eh_context *ehc = &link->eh_context;
+ struct ata_device *dev;
+
+ memset(&link->eh_context, 0, sizeof(link->eh_context));
+ link->eh_context.i = link->eh_info;
+ memset(&link->eh_info, 0, sizeof(link->eh_info));
+
+ ata_for_each_dev(dev, link, ENABLED) {
+ int devno = dev->devno;
+
+ ehc->saved_xfer_mode[devno] = dev->xfer_mode;
+ if (ata_ncq_enabled(dev))
+ ehc->saved_ncq_enabled |= 1 << devno;
+ }
+ }
+
+ ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
+ ap->pflags &= ~ATA_PFLAG_EH_PENDING;
+ ap->excl_link = NULL; /* don't maintain exclusion over EH */
+
+ 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 {
+ /* if unloading, commence suicide */
+ if ((ap->pflags & ATA_PFLAG_UNLOADING) &&
+ !(ap->pflags & ATA_PFLAG_UNLOADED))
+ ata_eh_unload(ap);
+ ata_eh_finish(ap);
+ }
+
+ /* process port suspend request */
+ ata_eh_handle_port_suspend(ap);
+
+ /* Exception might have happened 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 (--ap->eh_tries) {
+ spin_unlock_irqrestore(ap->lock, flags);
+ goto repeat;
+ }
+ ata_port_err(ap,
+ "EH pending after %d tries, giving up\n",
+ ATA_EH_MAX_TRIES);
+ ap->pflags &= ~ATA_PFLAG_EH_PENDING;
+ }
+
+ /* this run is complete, make sure EH info is clear */
+ ata_for_each_link(link, ap, HOST_FIRST)
+ memset(&link->eh_info, 0, sizeof(link->eh_info));
+
+ /* end eh (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.
+ */
+ ap->ops->end_eh(ap);
+
+ spin_unlock_irqrestore(ap->lock, flags);
+ ata_eh_release(ap);
+ } else {
+ WARN_ON(ata_qc_from_tag(ap, ap->link.active_tag) == NULL);
+ ap->ops->eng_timeout(ap);
+ }
+
+ 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)
+ schedule_delayed_work(&ap->hotplug_task, 0);
+
+ if (ap->pflags & ATA_PFLAG_RECOVERED)
+ ata_port_info(ap, "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);
+}
+EXPORT_SYMBOL_GPL(ata_scsi_port_error_handler);
+
+/**
+ * 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)) {
+ ata_msleep(ap, 10);
+ goto retry;
+ }
+}
+EXPORT_SYMBOL_GPL(ata_port_wait_eh);
+
+static int ata_eh_nr_in_flight(struct ata_port *ap)
+{
+ unsigned int tag;
+ int nr = 0;
+
+ /* count only non-internal commands */
+ for (tag = 0; tag < ATA_MAX_QUEUE - 1; tag++)
+ if (ata_qc_from_tag(ap, tag))
+ nr++;
+
+ return nr;
+}
+
+void ata_eh_fastdrain_timerfn(unsigned long arg)
+{
+ struct ata_port *ap = (void *)arg;
+ unsigned long flags;
+ int cnt;
+
+ spin_lock_irqsave(ap->lock, flags);
+
+ cnt = ata_eh_nr_in_flight(ap);
+
+ /* are we done? */
+ if (!cnt)
+ goto out_unlock;
+
+ if (cnt == ap->fastdrain_cnt) {
+ unsigned int tag;
+
+ /* No progress during the last interval, tag all
+ * in-flight qcs as timed out and freeze the port.
+ */
+ for (tag = 0; tag < ATA_MAX_QUEUE - 1; tag++) {
+ struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag);
+ if (qc)
+ qc->err_mask |= AC_ERR_TIMEOUT;
+ }
+
+ ata_port_freeze(ap);
+ } else {
+ /* some qcs have finished, give it another chance */
+ ap->fastdrain_cnt = cnt;
+ ap->fastdrain_timer.expires =
+ ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
+ add_timer(&ap->fastdrain_timer);
+ }
+
+ out_unlock:
+ spin_unlock_irqrestore(ap->lock, flags);
+}
+
+/**
+ * ata_eh_set_pending - set ATA_PFLAG_EH_PENDING and activate fast drain
+ * @ap: target ATA port
+ * @fastdrain: activate fast drain
+ *
+ * Set ATA_PFLAG_EH_PENDING and activate fast drain if @fastdrain
+ * is non-zero and EH wasn't pending before. Fast drain ensures
+ * that EH kicks in in timely manner.
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ */
+static void ata_eh_set_pending(struct ata_port *ap, int fastdrain)
+{
+ int cnt;
+
+ /* already scheduled? */
+ if (ap->pflags & ATA_PFLAG_EH_PENDING)
+ return;
+
+ ap->pflags |= ATA_PFLAG_EH_PENDING;
+
+ if (!fastdrain)
+ return;
+
+ /* do we have in-flight qcs? */
+ cnt = ata_eh_nr_in_flight(ap);
+ if (!cnt)
+ return;
+
+ /* activate fast drain */
+ ap->fastdrain_cnt = cnt;
+ ap->fastdrain_timer.expires =
+ ata_deadline(jiffies, ATA_EH_FASTDRAIN_INTERVAL);
+ add_timer(&ap->fastdrain_timer);
+}
+
+/**
+ * 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;
+ struct request_queue *q = qc->scsicmd->device->request_queue;
+ unsigned long flags;
+
+ WARN_ON(!ap->ops->error_handler);
+
+ qc->flags |= ATA_QCFLAG_FAILED;
+ ata_eh_set_pending(ap, 1);
+
+ /* 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.
+ */
+ spin_lock_irqsave(q->queue_lock, flags);
+ blk_abort_request(qc->scsicmd->request);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+}
+
+/**
+ * ata_std_sched_eh - non-libsas ata_ports issue eh with this common routine
+ * @ap: ATA port to schedule EH for
+ *
+ * LOCKING: inherited from ata_port_schedule_eh
+ * spin_lock_irqsave(host lock)
+ */
+void ata_std_sched_eh(struct ata_port *ap)
+{
+ WARN_ON(!ap->ops->error_handler);
+
+ if (ap->pflags & ATA_PFLAG_INITIALIZING)
+ return;
+
+ ata_eh_set_pending(ap, 1);
+ scsi_schedule_eh(ap->scsi_host);
+
+ DPRINTK("port EH scheduled\n");
+}
+EXPORT_SYMBOL_GPL(ata_std_sched_eh);
+
+/**
+ * ata_std_end_eh - non-libsas ata_ports complete eh with this common routine
+ * @ap: ATA port to end EH for
+ *
+ * In the libata object model there is a 1:1 mapping of ata_port to
+ * shost, so host fields can be directly manipulated under ap->lock, in
+ * the libsas case we need to hold a lock at the ha->level to coordinate
+ * these events.
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ */
+void ata_std_end_eh(struct ata_port *ap)
+{
+ struct Scsi_Host *host = ap->scsi_host;
+
+ host->host_eh_scheduled = 0;
+}
+EXPORT_SYMBOL(ata_std_end_eh);
+
+
+/**
+ * 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)
+{
+ /* see: ata_std_sched_eh, unless you know better */
+ ap->ops->sched_eh(ap);
+}
+
+static int ata_do_link_abort(struct ata_port *ap, struct ata_link *link)
+{
+ int tag, nr_aborted = 0;
+
+ WARN_ON(!ap->ops->error_handler);
+
+ /* we're gonna abort all commands, no need for fast drain */
+ ata_eh_set_pending(ap, 0);
+
+ for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
+ struct ata_queued_cmd *qc = ata_qc_from_tag(ap, tag);
+
+ if (qc && (!link || qc->dev->link == link)) {
+ qc->flags |= ATA_QCFLAG_FAILED;
+ ata_qc_complete(qc);
+ nr_aborted++;
+ }
+ }
+
+ if (!nr_aborted)
+ ata_port_schedule_eh(ap);
+
+ return nr_aborted;
+}
+
+/**
+ * ata_link_abort - abort all qc's on the link
+ * @link: ATA link to abort qc's for
+ *
+ * Abort all active qc's active on @link and schedule EH.
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ *
+ * RETURNS:
+ * Number of aborted qc's.
+ */
+int ata_link_abort(struct ata_link *link)
+{
+ return ata_do_link_abort(link->ap, link);
+}
+
+/**
+ * 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_set lock)
+ *
+ * RETURNS:
+ * Number of aborted qc's.
+ */
+int ata_port_abort(struct ata_port *ap)
+{
+ return ata_do_link_abort(ap, NULL);
+}
+
+/**
+ * __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->print_id);
+}
+
+/**
+ * ata_port_freeze - abort & freeze port
+ * @ap: ATA port to freeze
+ *
+ * Abort and freeze @ap. The freeze operation must be called
+ * first, because some hardware requires special operations
+ * before the taskfile registers are accessible.
+ *
+ * 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);
+
+ __ata_port_freeze(ap);
+ nr_aborted = ata_port_abort(ap);
+
+ return nr_aborted;
+}
+
+/**
+ * sata_async_notification - SATA async notification handler
+ * @ap: ATA port where async notification is received
+ *
+ * Handler to be called when async notification via SDB FIS is
+ * received. This function schedules EH if necessary.
+ *
+ * LOCKING:
+ * spin_lock_irqsave(host lock)
+ *
+ * RETURNS:
+ * 1 if EH is scheduled, 0 otherwise.
+ */
+int sata_async_notification(struct ata_port *ap)
+{
+ u32 sntf;
+ int rc;
+
+ if (!(ap->flags & ATA_FLAG_AN))
+ return 0;
+
+ rc = sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf);
+ if (rc == 0)
+ sata_scr_write(&ap->link, SCR_NOTIFICATION, sntf);
+
+ if (!sata_pmp_attached(ap) || rc) {
+ /* PMP is not attached or SNTF is not available */
+ if (!sata_pmp_attached(ap)) {
+ /* PMP is not attached. Check whether ATAPI
+ * AN is configured. If so, notify media
+ * change.
+ */
+ struct ata_device *dev = ap->link.device;
+
+ if ((dev->class == ATA_DEV_ATAPI) &&
+ (dev->flags & ATA_DFLAG_AN))
+ ata_scsi_media_change_notify(dev);
+ return 0;
+ } else {
+ /* PMP is attached but SNTF is not available.
+ * ATAPI async media change notification is
+ * not used. The PMP must be reporting PHY
+ * status change, schedule EH.
+ */
+ ata_port_schedule_eh(ap);
+ return 1;
+ }
+ } else {
+ /* PMP is attached and SNTF is available */
+ struct ata_link *link;
+
+ /* check and notify ATAPI AN */
+ ata_for_each_link(link, ap, EDGE) {
+ if (!(sntf & (1 << link->pmp)))
+ continue;
+
+ if ((link->device->class == ATA_DEV_ATAPI) &&
+ (link->device->flags & ATA_DFLAG_AN))
+ ata_scsi_media_change_notify(link->device);
+ }
+
+ /* If PMP is reporting that PHY status of some
+ * downstream ports has changed, schedule EH.
+ */
+ if (sntf & (1 << SATA_PMP_CTRL_PORT)) {
+ ata_port_schedule_eh(ap);
+ return 1;
+ }
+
+ return 0;
+ }
+}
+
+/**
+ * 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->print_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->allowed is incremented 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->allowed++;
+ __ata_eh_qc_complete(qc);
+}
+
+/**
+ * ata_dev_disable - disable ATA device
+ * @dev: ATA device to disable
+ *
+ * Disable @dev.
+ *
+ * Locking:
+ * EH context.
+ */
+void ata_dev_disable(struct ata_device *dev)
+{
+ if (!ata_dev_enabled(dev))
+ return;
+
+ if (ata_msg_drv(dev->link->ap))
+ ata_dev_warn(dev, "disabled\n");
+ ata_acpi_on_disable(dev);
+ ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 | ATA_DNXFER_QUIET);
+ dev->class++;
+
+ /* From now till the next successful probe, ering is used to
+ * track probe failures. Clear accumulated device error info.
+ */
+ ata_ering_clear(&dev->ering);
+}
+
+/**
+ * ata_eh_detach_dev - detach ATA device
+ * @dev: ATA device to detach
+ *
+ * Detach @dev.
+ *
+ * LOCKING:
+ * None.
+ */
+void ata_eh_detach_dev(struct ata_device *dev)
+{
+ struct ata_link *link = dev->link;
+ struct ata_port *ap = link->ap;
+ struct ata_eh_context *ehc = &link->eh_context;
+ 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 info */
+ ata_eh_clear_action(link, dev, &link->eh_info, ATA_EH_PERDEV_MASK);
+ ata_eh_clear_action(link, dev, &link->eh_context.i, ATA_EH_PERDEV_MASK);
+ ehc->saved_xfer_mode[dev->devno] = 0;
+ ehc->saved_ncq_enabled &= ~(1 << dev->devno);
+
+ spin_unlock_irqrestore(ap->lock, flags);
+}
+
+/**
+ * ata_eh_about_to_do - about to perform eh_action
+ * @link: target ATA link
+ * @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 @link->eh_info such that eh actions are not unnecessarily
+ * repeated.
+ *
+ * LOCKING:
+ * None.
+ */
+void ata_eh_about_to_do(struct ata_link *link, struct ata_device *dev,
+ unsigned int action)
+{
+ struct ata_port *ap = link->ap;
+ struct ata_eh_info *ehi = &link->eh_info;
+ struct ata_eh_context *ehc = &link->eh_context;
+ unsigned long flags;
+
+ spin_lock_irqsave(ap->lock, flags);
+
+ ata_eh_clear_action(link, dev, ehi, action);
+
+ /* About to take EH action, set RECOVERED. Ignore actions on
+ * slave links as master will do them again.
+ */
+ if (!(ehc->i.flags & ATA_EHI_QUIET) && link != ap->slave_link)
+ 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 @link->eh_context.
+ *
+ * LOCKING:
+ * None.
+ */
+void ata_eh_done(struct ata_link *link, struct ata_device *dev,
+ unsigned int action)
+{
+ struct ata_eh_context *ehc = &link->eh_context;
+
+ ata_eh_clear_action(link, dev, &ehc->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
+ * @log: log to read
+ * @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.
+ */
+unsigned int ata_read_log_page(struct ata_device *dev, u8 log,
+ u8 page, void *buf, unsigned int sectors)
+{
+ struct ata_taskfile tf;
+ unsigned int err_mask;
+
+ DPRINTK("read log page - log 0x%x, page 0x%x\n", log, page);
+
+ ata_tf_init(dev, &tf);
+ if (dev->dma_mode && ata_id_has_read_log_dma_ext(dev->id)) {
+ tf.command = ATA_CMD_READ_LOG_DMA_EXT;
+ tf.protocol = ATA_PROT_DMA;
+ } else {
+ tf.command = ATA_CMD_READ_LOG_EXT;
+ tf.protocol = ATA_PROT_PIO;
+ }
+ tf.lbal = log;
+ tf.lbam = page;
+ tf.nsect = sectors;
+ tf.hob_nsect = sectors >> 8;
+ tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_LBA48 | ATA_TFLAG_DEVICE;
+
+ err_mask = ata_exec_internal(dev, &tf, NULL, DMA_FROM_DEVICE,
+ buf, sectors * ATA_SECT_SIZE, 0);
+
+ 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->link->ap->sector_buf;
+ unsigned int err_mask;
+ u8 csum;
+ int i;
+
+ err_mask = ata_read_log_page(dev, ATA_LOG_SATA_NCQ, 0, buf, 1);
+ if (err_mask)
+ return -EIO;
+
+ csum = 0;
+ for (i = 0; i < ATA_SECT_SIZE; i++)
+ csum += buf[i];
+ if (csum)
+ ata_dev_warn(dev, "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];
+ if (ata_id_has_ncq_autosense(dev->id))
+ tf->auxiliary = buf[14] << 16 | buf[15] << 8 | buf[16];
+
+ return 0;
+}
+
+/**
+ * atapi_eh_tur - perform ATAPI TEST_UNIT_READY
+ * @dev: target ATAPI device
+ * @r_sense_key: out parameter for sense_key
+ *
+ * Perform ATAPI TEST_UNIT_READY.
+ *
+ * LOCKING:
+ * EH context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, AC_ERR_* mask on failure.
+ */
+unsigned int atapi_eh_tur(struct ata_device *dev, u8 *r_sense_key)
+{
+ u8 cdb[ATAPI_CDB_LEN] = { TEST_UNIT_READY, 0, 0, 0, 0, 0 };
+ struct ata_taskfile tf;
+ unsigned int err_mask;
+
+ ata_tf_init(dev, &tf);
+
+ tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+ tf.command = ATA_CMD_PACKET;
+ tf.protocol = ATAPI_PROT_NODATA;
+
+ err_mask = ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
+ if (err_mask == AC_ERR_DEV)
+ *r_sense_key = tf.feature >> 4;
+ return err_mask;
+}
+
+/**
+ * ata_eh_request_sense - perform REQUEST_SENSE_DATA_EXT
+ * @dev: device to perform REQUEST_SENSE_SENSE_DATA_EXT to
+ * @sense_buf: result sense data buffer (SCSI_SENSE_BUFFERSIZE bytes long)
+ * @dfl_sense_key: default sense key to use
+ *
+ * Perform REQUEST_SENSE_DATA_EXT after the device reported CHECK
+ * SENSE. This function is EH helper.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ *
+ * RETURNS:
+ * encoded sense data on success, 0 on failure or if sense data
+ * is not available.
+ */
+static u32 ata_eh_request_sense(struct ata_queued_cmd *qc,
+ struct scsi_cmnd *cmd)
+{
+ struct ata_device *dev = qc->dev;
+ struct ata_taskfile tf;
+ unsigned int err_mask;
+
+ if (!cmd)
+ return 0;
+
+ DPRINTK("ATA request sense\n");
+ ata_dev_warn(dev, "request sense\n");
+ if (!ata_id_sense_reporting_enabled(dev->id)) {
+ ata_dev_warn(qc->dev, "sense data reporting disabled\n");
+ return 0;
+ }
+ ata_tf_init(dev, &tf);
+
+ tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+ tf.flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
+ tf.command = ATA_CMD_REQ_SENSE_DATA;
+ tf.protocol = ATA_PROT_NODATA;
+
+ err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
+ /*
+ * ACS-4 states:
+ * The device may set the SENSE DATA AVAILABLE bit to one in the
+ * STATUS field and clear the ERROR bit to zero in the STATUS field
+ * to indicate that the command returned completion without an error
+ * and the sense data described in table 306 is available.
+ *
+ * IOW the 'ATA_SENSE' bit might not be set even though valid
+ * sense data is available.
+ * So check for both.
+ */
+ if ((tf.command & ATA_SENSE) ||
+ tf.lbah != 0 || tf.lbam != 0 || tf.lbal != 0) {
+ ata_scsi_set_sense(cmd, tf.lbah, tf.lbam, tf.lbal);
+ qc->flags |= ATA_QCFLAG_SENSE_VALID;
+ ata_dev_warn(dev, "sense data %02x/%02x/%02x\n",
+ tf.lbah, tf.lbam, tf.lbal);
+ } else {
+ ata_dev_warn(dev, "request sense failed stat %02x emask %x\n",
+ tf.command, err_mask);
+ }
+ return err_mask;
+}
+
+/**
+ * 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)
+ * @dfl_sense_key: default sense key to use
+ *
+ * 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
+ */
+unsigned int atapi_eh_request_sense(struct ata_device *dev,
+ u8 *sense_buf, u8 dfl_sense_key)
+{
+ u8 cdb[ATAPI_CDB_LEN] =
+ { REQUEST_SENSE, 0, 0, 0, SCSI_SENSE_BUFFERSIZE, 0 };
+ struct ata_port *ap = dev->link->ap;
+ struct ata_taskfile tf;
+
+ DPRINTK("ATAPI request sense\n");
+
+ memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
+
+ /* initialize sense_buf with the error register,
+ * for the case where they are -not- overwritten
+ */
+ sense_buf[0] = 0x70;
+ sense_buf[2] = dfl_sense_key;
+
+ /* some devices time out if garbage left in tf */
+ ata_tf_init(dev, &tf);
+
+ 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 = ATAPI_PROT_DMA;
+ tf.feature |= ATAPI_PKT_DMA;
+ } else {
+ tf.protocol = ATAPI_PROT_PIO;
+ tf.lbam = SCSI_SENSE_BUFFERSIZE;
+ tf.lbah = 0;
+ }
+
+ return ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
+ sense_buf, SCSI_SENSE_BUFFERSIZE, 0);
+}
+
+/**
+ * ata_eh_analyze_serror - analyze SError for a failed port
+ * @link: ATA link to analyze SError for
+ *
+ * Analyze SError if available and further determine cause of
+ * failure.
+ *
+ * LOCKING:
+ * None.
+ */
+static void ata_eh_analyze_serror(struct ata_link *link)
+{
+ struct ata_eh_context *ehc = &link->eh_context;
+ u32 serror = ehc->i.serror;
+ unsigned int err_mask = 0, action = 0;
+ u32 hotplug_mask;
+
+ if (serror & (SERR_PERSISTENT | SERR_DATA)) {
+ err_mask |= AC_ERR_ATA_BUS;
+ action |= ATA_EH_RESET;
+ }
+ if (serror & SERR_PROTOCOL) {
+ err_mask |= AC_ERR_HSM;
+ action |= ATA_EH_RESET;
+ }
+ if (serror & SERR_INTERNAL) {
+ err_mask |= AC_ERR_SYSTEM;
+ action |= ATA_EH_RESET;
+ }
+
+ /* Determine whether a hotplug event has occurred. Both
+ * SError.N/X are considered hotplug events for enabled or
+ * host links. For disabled PMP links, only N bit is
+ * considered as X bit is left at 1 for link plugging.
+ */
+ if (link->lpm_policy > ATA_LPM_MAX_POWER)
+ hotplug_mask = 0; /* hotplug doesn't work w/ LPM */
+ else if (!(link->flags & ATA_LFLAG_DISABLED) || ata_is_host_link(link))
+ hotplug_mask = SERR_PHYRDY_CHG | SERR_DEV_XCHG;
+ else
+ hotplug_mask = SERR_PHYRDY_CHG;
+
+ if (serror & hotplug_mask)
+ ata_ehi_hotplugged(&ehc->i);
+
+ ehc->i.err_mask |= err_mask;
+ ehc->i.action |= action;
+}
+
+/**
+ * ata_eh_analyze_ncq_error - analyze NCQ error
+ * @link: ATA link 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).
+ */
+void ata_eh_analyze_ncq_error(struct ata_link *link)
+{
+ struct ata_port *ap = link->ap;
+ struct ata_eh_context *ehc = &link->eh_context;
+ struct ata_device *dev = link->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 (!link->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 */
+ memset(&tf, 0, sizeof(tf));
+ rc = ata_eh_read_log_10h(dev, &tag, &tf);
+ if (rc) {
+ ata_link_err(link, "failed to read log page 10h (errno=%d)\n",
+ rc);
+ return;
+ }
+
+ if (!(link->sactive & (1 << tag))) {
+ ata_link_err(link, "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->result_tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
+ qc->err_mask |= AC_ERR_DEV | AC_ERR_NCQ;
+ if (qc->result_tf.auxiliary) {
+ char sense_key, asc, ascq;
+
+ sense_key = (qc->result_tf.auxiliary >> 16) & 0xff;
+ asc = (qc->result_tf.auxiliary >> 8) & 0xff;
+ ascq = qc->result_tf.auxiliary & 0xff;
+ ata_dev_dbg(dev, "NCQ Autosense %02x/%02x/%02x\n",
+ sense_key, asc, ascq);
+ ata_scsi_set_sense(qc->scsicmd, sense_key, asc, ascq);
+ ata_scsi_set_sense_information(qc->scsicmd, &qc->result_tf);
+ qc->flags |= ATA_QCFLAG_SENSE_VALID;
+ }
+
+ 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
+ * available.
+ *
+ * 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_RESET;
+ }
+
+ /*
+ * Sense data reporting does not work if the
+ * device fault bit is set.
+ */
+ if ((stat & ATA_SENSE) && !(stat & ATA_DF) &&
+ !(qc->flags & ATA_QCFLAG_SENSE_VALID)) {
+ if (!(qc->ap->pflags & ATA_PFLAG_FROZEN)) {
+ tmp = ata_eh_request_sense(qc, qc->scsicmd);
+ if (tmp)
+ qc->err_mask |= tmp;
+ else
+ ata_scsi_set_sense_information(qc->scsicmd, tf);
+ } else {
+ ata_dev_warn(qc->dev, "sense data available but port frozen\n");
+ }
+ }
+
+ /* Set by NCQ autosense or request sense above */
+ if (qc->flags & ATA_QCFLAG_SENSE_VALID)
+ return 0;
+
+ if (stat & (ATA_ERR | ATA_DF))
+ qc->err_mask |= AC_ERR_DEV;
+ else
+ return 0;
+
+ switch (qc->dev->class) {
+ case ATA_DEV_ATA:
+ case ATA_DEV_ZAC:
+ if (err & ATA_ICRC)
+ qc->err_mask |= AC_ERR_ATA_BUS;
+ if (err & (ATA_UNC | ATA_AMNF))
+ 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,
+ qc->result_tf.feature >> 4);
+ 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_RESET;
+
+ return action;
+}
+
+static int ata_eh_categorize_error(unsigned int eflags, unsigned int err_mask,
+ int *xfer_ok)
+{
+ int base = 0;
+
+ if (!(eflags & ATA_EFLAG_DUBIOUS_XFER))
+ *xfer_ok = 1;
+
+ if (!*xfer_ok)
+ base = ATA_ECAT_DUBIOUS_NONE;
+
+ if (err_mask & AC_ERR_ATA_BUS)
+ return base + ATA_ECAT_ATA_BUS;
+
+ if (err_mask & AC_ERR_TIMEOUT)
+ return base + ATA_ECAT_TOUT_HSM;
+
+ if (eflags & ATA_EFLAG_IS_IO) {
+ if (err_mask & AC_ERR_HSM)
+ return base + ATA_ECAT_TOUT_HSM;
+ if ((err_mask &
+ (AC_ERR_DEV|AC_ERR_MEDIA|AC_ERR_INVALID)) == AC_ERR_DEV)
+ return base + ATA_ECAT_UNK_DEV;
+ }
+
+ return 0;
+}
+
+struct speed_down_verdict_arg {
+ u64 since;
+ int xfer_ok;
+ int nr_errors[ATA_ECAT_NR];
+};
+
+static int speed_down_verdict_cb(struct ata_ering_entry *ent, void *void_arg)
+{
+ struct speed_down_verdict_arg *arg = void_arg;
+ int cat;
+
+ if ((ent->eflags & ATA_EFLAG_OLD_ER) || (ent->timestamp < arg->since))
+ return -1;
+
+ cat = ata_eh_categorize_error(ent->eflags, ent->err_mask,
+ &arg->xfer_ok);
+ arg->nr_errors[cat]++;
+
+ return 0;
+}
+
+/**
+ * ata_eh_speed_down_verdict - Determine speed down verdict
+ * @dev: Device of interest
+ *
+ * This function examines error ring of @dev and determines
+ * whether NCQ needs to be turned off, transfer speed should be
+ * stepped down, or falling back to PIO is necessary.
+ *
+ * ECAT_ATA_BUS : ATA_BUS error for any command
+ *
+ * ECAT_TOUT_HSM : TIMEOUT for any command or HSM violation for
+ * IO commands
+ *
+ * ECAT_UNK_DEV : Unknown DEV error for IO commands
+ *
+ * ECAT_DUBIOUS_* : Identical to above three but occurred while
+ * data transfer hasn't been verified.
+ *
+ * Verdicts are
+ *
+ * NCQ_OFF : Turn off NCQ.
+ *
+ * SPEED_DOWN : Speed down transfer speed but don't fall back
+ * to PIO.
+ *
+ * FALLBACK_TO_PIO : Fall back to PIO.
+ *
+ * Even if multiple verdicts are returned, only one action is
+ * taken per error. An action triggered by non-DUBIOUS errors
+ * clears ering, while one triggered by DUBIOUS_* errors doesn't.
+ * This is to expedite speed down decisions right after device is
+ * initially configured.
+ *
+ * The followings are speed down rules. #1 and #2 deal with
+ * DUBIOUS errors.
+ *
+ * 1. If more than one DUBIOUS_ATA_BUS or DUBIOUS_TOUT_HSM errors
+ * occurred during last 5 mins, SPEED_DOWN and FALLBACK_TO_PIO.
+ *
+ * 2. If more than one DUBIOUS_TOUT_HSM or DUBIOUS_UNK_DEV errors
+ * occurred during last 5 mins, NCQ_OFF.
+ *
+ * 3. If more than 8 ATA_BUS, TOUT_HSM or UNK_DEV errors
+ * occurred during last 5 mins, FALLBACK_TO_PIO
+ *
+ * 4. If more than 3 TOUT_HSM or UNK_DEV errors occurred
+ * during last 10 mins, NCQ_OFF.
+ *
+ * 5. If more than 3 ATA_BUS or TOUT_HSM errors, or more than 6
+ * UNK_DEV errors occurred during last 10 mins, SPEED_DOWN.
+ *
+ * LOCKING:
+ * Inherited from caller.
+ *
+ * RETURNS:
+ * OR of ATA_EH_SPDN_* flags.
+ */
+static unsigned int ata_eh_speed_down_verdict(struct ata_device *dev)
+{
+ const u64 j5mins = 5LLU * 60 * HZ, j10mins = 10LLU * 60 * HZ;
+ u64 j64 = get_jiffies_64();
+ struct speed_down_verdict_arg arg;
+ unsigned int verdict = 0;
+
+ /* scan past 5 mins of error history */
+ memset(&arg, 0, sizeof(arg));
+ arg.since = j64 - min(j64, j5mins);
+ ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
+
+ if (arg.nr_errors[ATA_ECAT_DUBIOUS_ATA_BUS] +
+ arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] > 1)
+ verdict |= ATA_EH_SPDN_SPEED_DOWN |
+ ATA_EH_SPDN_FALLBACK_TO_PIO | ATA_EH_SPDN_KEEP_ERRORS;
+
+ if (arg.nr_errors[ATA_ECAT_DUBIOUS_TOUT_HSM] +
+ arg.nr_errors[ATA_ECAT_DUBIOUS_UNK_DEV] > 1)
+ verdict |= ATA_EH_SPDN_NCQ_OFF | ATA_EH_SPDN_KEEP_ERRORS;
+
+ if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
+ arg.nr_errors[ATA_ECAT_TOUT_HSM] +
+ arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
+ verdict |= ATA_EH_SPDN_FALLBACK_TO_PIO;
+
+ /* scan past 10 mins of error history */
+ memset(&arg, 0, sizeof(arg));
+ arg.since = j64 - min(j64, j10mins);
+ ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg);
+
+ if (arg.nr_errors[ATA_ECAT_TOUT_HSM] +
+ arg.nr_errors[ATA_ECAT_UNK_DEV] > 3)
+ verdict |= ATA_EH_SPDN_NCQ_OFF;
+
+ if (arg.nr_errors[ATA_ECAT_ATA_BUS] +
+ arg.nr_errors[ATA_ECAT_TOUT_HSM] > 3 ||
+ arg.nr_errors[ATA_ECAT_UNK_DEV] > 6)
+ verdict |= ATA_EH_SPDN_SPEED_DOWN;
+
+ return verdict;
+}
+
+/**
+ * ata_eh_speed_down - record error and speed down if necessary
+ * @dev: Failed device
+ * @eflags: mask of ATA_EFLAG_* flags
+ * @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:
+ * Determined recovery action.
+ */
+static unsigned int ata_eh_speed_down(struct ata_device *dev,
+ unsigned int eflags, unsigned int err_mask)
+{
+ struct ata_link *link = ata_dev_phys_link(dev);
+ int xfer_ok = 0;
+ unsigned int verdict;
+ unsigned int action = 0;
+
+ /* don't bother if Cat-0 error */
+ if (ata_eh_categorize_error(eflags, err_mask, &xfer_ok) == 0)
+ return 0;
+
+ /* record error and determine whether speed down is necessary */
+ ata_ering_record(&dev->ering, eflags, err_mask);
+ verdict = ata_eh_speed_down_verdict(dev);
+
+ /* turn off NCQ? */
+ if ((verdict & ATA_EH_SPDN_NCQ_OFF) &&
+ (dev->flags & (ATA_DFLAG_PIO | ATA_DFLAG_NCQ |
+ ATA_DFLAG_NCQ_OFF)) == ATA_DFLAG_NCQ) {
+ dev->flags |= ATA_DFLAG_NCQ_OFF;
+ ata_dev_warn(dev, "NCQ disabled due to excessive errors\n");
+ goto done;
+ }
+
+ /* speed down? */
+ if (verdict & ATA_EH_SPDN_SPEED_DOWN) {
+ /* speed down SATA link speed if possible */
+ if (sata_down_spd_limit(link, 0) == 0) {
+ action |= ATA_EH_RESET;
+ goto done;
+ }
+
+ /* lower transfer mode */
+ if (dev->spdn_cnt < 2) {
+ static const int dma_dnxfer_sel[] =
+ { ATA_DNXFER_DMA, ATA_DNXFER_40C };
+ static const int pio_dnxfer_sel[] =
+ { ATA_DNXFER_PIO, ATA_DNXFER_FORCE_PIO0 };
+ int sel;
+
+ if (dev->xfer_shift != ATA_SHIFT_PIO)
+ sel = dma_dnxfer_sel[dev->spdn_cnt];
+ else
+ sel = pio_dnxfer_sel[dev->spdn_cnt];
+
+ dev->spdn_cnt++;
+
+ if (ata_down_xfermask_limit(dev, sel) == 0) {
+ action |= ATA_EH_RESET;
+ goto done;
+ }
+ }
+ }
+
+ /* Fall back to PIO? Slowing down to PIO is meaningless for
+ * SATA ATA devices. Consider it only for PATA and SATAPI.
+ */
+ if ((verdict & ATA_EH_SPDN_FALLBACK_TO_PIO) && (dev->spdn_cnt >= 2) &&
+ (link->ap->cbl != ATA_CBL_SATA || dev->class == ATA_DEV_ATAPI) &&
+ (dev->xfer_shift != ATA_SHIFT_PIO)) {
+ if (ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO) == 0) {
+ dev->spdn_cnt = 0;
+ action |= ATA_EH_RESET;
+ goto done;
+ }
+ }
+
+ return 0;
+ done:
+ /* device has been slowed down, blow error history */
+ if (!(verdict & ATA_EH_SPDN_KEEP_ERRORS))
+ ata_ering_clear(&dev->ering);
+ return action;
+}
+
+/**
+ * ata_eh_worth_retry - analyze error and decide whether to retry
+ * @qc: qc to possibly retry
+ *
+ * Look at the cause of the error and decide if a retry
+ * might be useful or not. We don't want to retry media errors
+ * because the drive itself has probably already taken 10-30 seconds
+ * doing its own internal retries before reporting the failure.
+ */
+static inline int ata_eh_worth_retry(struct ata_queued_cmd *qc)
+{
+ if (qc->err_mask & AC_ERR_MEDIA)
+ return 0; /* don't retry media errors */
+ if (qc->flags & ATA_QCFLAG_IO)
+ return 1; /* otherwise retry anything from fs stack */
+ if (qc->err_mask & AC_ERR_INVALID)
+ return 0; /* don't retry these */
+ return qc->err_mask != AC_ERR_DEV; /* retry if not dev error */
+}
+
+/**
+ * ata_eh_link_autopsy - analyze error and determine recovery action
+ * @link: host link to perform autopsy on
+ *
+ * Analyze why @link failed and determine which recovery actions
+ * are 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_link_autopsy(struct ata_link *link)
+{
+ struct ata_port *ap = link->ap;
+ struct ata_eh_context *ehc = &link->eh_context;
+ struct ata_device *dev;
+ unsigned int all_err_mask = 0, eflags = 0;
+ int tag;
+ u32 serror;
+ int rc;
+
+ DPRINTK("ENTER\n");
+
+ if (ehc->i.flags & ATA_EHI_NO_AUTOPSY)
+ return;
+
+ /* obtain and analyze SError */
+ rc = sata_scr_read(link, SCR_ERROR, &serror);
+ if (rc == 0) {
+ ehc->i.serror |= serror;
+ ata_eh_analyze_serror(link);
+ } else if (rc != -EOPNOTSUPP) {
+ /* SError read failed, force reset and probing */
+ ehc->i.probe_mask |= ATA_ALL_DEVICES;
+ ehc->i.action |= ATA_EH_RESET;
+ ehc->i.err_mask |= AC_ERR_OTHER;
+ }
+
+ /* analyze NCQ failure */
+ ata_eh_analyze_ncq_error(link);
+
+ /* 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) ||
+ ata_dev_phys_link(qc->dev) != link)
+ 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);
+
+ /* determine whether the command is worth retrying */
+ if (ata_eh_worth_retry(qc))
+ qc->flags |= ATA_QCFLAG_RETRY;
+
+ /* accumulate error info */
+ ehc->i.dev = qc->dev;
+ all_err_mask |= qc->err_mask;
+ if (qc->flags & ATA_QCFLAG_IO)
+ eflags |= ATA_EFLAG_IS_IO;
+ trace_ata_eh_link_autopsy_qc(qc);
+ }
+
+ /* enforce default EH actions */
+ if (ap->pflags & ATA_PFLAG_FROZEN ||
+ all_err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT))
+ ehc->i.action |= ATA_EH_RESET;
+ else if (((eflags & ATA_EFLAG_IS_IO) && all_err_mask) ||
+ (!(eflags & ATA_EFLAG_IS_IO) && (all_err_mask & ~AC_ERR_DEV)))
+ ehc->i.action |= ATA_EH_REVALIDATE;
+
+ /* If we have offending qcs and the associated failed device,
+ * perform per-dev EH action only on the offending device.
+ */
+ if (ehc->i.dev) {
+ ehc->i.dev_action[ehc->i.dev->devno] |=
+ ehc->i.action & ATA_EH_PERDEV_MASK;
+ ehc->i.action &= ~ATA_EH_PERDEV_MASK;
+ }
+
+ /* propagate timeout to host link */
+ if ((all_err_mask & AC_ERR_TIMEOUT) && !ata_is_host_link(link))
+ ap->link.eh_context.i.err_mask |= AC_ERR_TIMEOUT;
+
+ /* record error and consider speeding down */
+ dev = ehc->i.dev;
+ if (!dev && ((ata_link_max_devices(link) == 1 &&
+ ata_dev_enabled(link->device))))
+ dev = link->device;
+
+ if (dev) {
+ if (dev->flags & ATA_DFLAG_DUBIOUS_XFER)
+ eflags |= ATA_EFLAG_DUBIOUS_XFER;
+ ehc->i.action |= ata_eh_speed_down(dev, eflags, all_err_mask);
+ }
+ trace_ata_eh_link_autopsy(dev, ehc->i.action, all_err_mask);
+ DPRINTK("EXIT\n");
+}
+
+/**
+ * ata_eh_autopsy - analyze error and determine recovery action
+ * @ap: host port to perform autopsy on
+ *
+ * Analyze all links of @ap and determine why they failed and
+ * which recovery actions are needed.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ */
+void ata_eh_autopsy(struct ata_port *ap)
+{
+ struct ata_link *link;
+
+ ata_for_each_link(link, ap, EDGE)
+ ata_eh_link_autopsy(link);
+
+ /* Handle the frigging slave link. Autopsy is done similarly
+ * but actions and flags are transferred over to the master
+ * link and handled from there.
+ */
+ if (ap->slave_link) {
+ struct ata_eh_context *mehc = &ap->link.eh_context;
+ struct ata_eh_context *sehc = &ap->slave_link->eh_context;
+
+ /* transfer control flags from master to slave */
+ sehc->i.flags |= mehc->i.flags & ATA_EHI_TO_SLAVE_MASK;
+
+ /* perform autopsy on the slave link */
+ ata_eh_link_autopsy(ap->slave_link);
+
+ /* transfer actions from slave to master and clear slave */
+ ata_eh_about_to_do(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
+ mehc->i.action |= sehc->i.action;
+ mehc->i.dev_action[1] |= sehc->i.dev_action[1];
+ mehc->i.flags |= sehc->i.flags;
+ ata_eh_done(ap->slave_link, NULL, ATA_EH_ALL_ACTIONS);
+ }
+
+ /* Autopsy of fanout ports can affect host link autopsy.
+ * Perform host link autopsy last.
+ */
+ if (sata_pmp_attached(ap))
+ ata_eh_link_autopsy(&ap->link);
+}
+
+/**
+ * ata_get_cmd_descript - get description for ATA command
+ * @command: ATA command code to get description for
+ *
+ * Return a textual description of the given command, or NULL if the
+ * command is not known.
+ *
+ * LOCKING:
+ * None
+ */
+const char *ata_get_cmd_descript(u8 command)
+{
+#ifdef CONFIG_ATA_VERBOSE_ERROR
+ static const struct
+ {
+ u8 command;
+ const char *text;
+ } cmd_descr[] = {
+ { ATA_CMD_DEV_RESET, "DEVICE RESET" },
+ { ATA_CMD_CHK_POWER, "CHECK POWER MODE" },
+ { ATA_CMD_STANDBY, "STANDBY" },
+ { ATA_CMD_IDLE, "IDLE" },
+ { ATA_CMD_EDD, "EXECUTE DEVICE DIAGNOSTIC" },
+ { ATA_CMD_DOWNLOAD_MICRO, "DOWNLOAD MICROCODE" },
+ { ATA_CMD_DOWNLOAD_MICRO_DMA, "DOWNLOAD MICROCODE DMA" },
+ { ATA_CMD_NOP, "NOP" },
+ { ATA_CMD_FLUSH, "FLUSH CACHE" },
+ { ATA_CMD_FLUSH_EXT, "FLUSH CACHE EXT" },
+ { ATA_CMD_ID_ATA, "IDENTIFY DEVICE" },
+ { ATA_CMD_ID_ATAPI, "IDENTIFY PACKET DEVICE" },
+ { ATA_CMD_SERVICE, "SERVICE" },
+ { ATA_CMD_READ, "READ DMA" },
+ { ATA_CMD_READ_EXT, "READ DMA EXT" },
+ { ATA_CMD_READ_QUEUED, "READ DMA QUEUED" },
+ { ATA_CMD_READ_STREAM_EXT, "READ STREAM EXT" },
+ { ATA_CMD_READ_STREAM_DMA_EXT, "READ STREAM DMA EXT" },
+ { ATA_CMD_WRITE, "WRITE DMA" },
+ { ATA_CMD_WRITE_EXT, "WRITE DMA EXT" },
+ { ATA_CMD_WRITE_QUEUED, "WRITE DMA QUEUED EXT" },
+ { ATA_CMD_WRITE_STREAM_EXT, "WRITE STREAM EXT" },
+ { ATA_CMD_WRITE_STREAM_DMA_EXT, "WRITE STREAM DMA EXT" },
+ { ATA_CMD_WRITE_FUA_EXT, "WRITE DMA FUA EXT" },
+ { ATA_CMD_WRITE_QUEUED_FUA_EXT, "WRITE DMA QUEUED FUA EXT" },
+ { ATA_CMD_FPDMA_READ, "READ FPDMA QUEUED" },
+ { ATA_CMD_FPDMA_WRITE, "WRITE FPDMA QUEUED" },
+ { ATA_CMD_FPDMA_SEND, "SEND FPDMA QUEUED" },
+ { ATA_CMD_FPDMA_RECV, "RECEIVE FPDMA QUEUED" },
+ { ATA_CMD_PIO_READ, "READ SECTOR(S)" },
+ { ATA_CMD_PIO_READ_EXT, "READ SECTOR(S) EXT" },
+ { ATA_CMD_PIO_WRITE, "WRITE SECTOR(S)" },
+ { ATA_CMD_PIO_WRITE_EXT, "WRITE SECTOR(S) EXT" },
+ { ATA_CMD_READ_MULTI, "READ MULTIPLE" },
+ { ATA_CMD_READ_MULTI_EXT, "READ MULTIPLE EXT" },
+ { ATA_CMD_WRITE_MULTI, "WRITE MULTIPLE" },
+ { ATA_CMD_WRITE_MULTI_EXT, "WRITE MULTIPLE EXT" },
+ { ATA_CMD_WRITE_MULTI_FUA_EXT, "WRITE MULTIPLE FUA EXT" },
+ { ATA_CMD_SET_FEATURES, "SET FEATURES" },
+ { ATA_CMD_SET_MULTI, "SET MULTIPLE MODE" },
+ { ATA_CMD_VERIFY, "READ VERIFY SECTOR(S)" },
+ { ATA_CMD_VERIFY_EXT, "READ VERIFY SECTOR(S) EXT" },
+ { ATA_CMD_WRITE_UNCORR_EXT, "WRITE UNCORRECTABLE EXT" },
+ { ATA_CMD_STANDBYNOW1, "STANDBY IMMEDIATE" },
+ { ATA_CMD_IDLEIMMEDIATE, "IDLE IMMEDIATE" },
+ { ATA_CMD_SLEEP, "SLEEP" },
+ { ATA_CMD_INIT_DEV_PARAMS, "INITIALIZE DEVICE PARAMETERS" },
+ { ATA_CMD_READ_NATIVE_MAX, "READ NATIVE MAX ADDRESS" },
+ { ATA_CMD_READ_NATIVE_MAX_EXT, "READ NATIVE MAX ADDRESS EXT" },
+ { ATA_CMD_SET_MAX, "SET MAX ADDRESS" },
+ { ATA_CMD_SET_MAX_EXT, "SET MAX ADDRESS EXT" },
+ { ATA_CMD_READ_LOG_EXT, "READ LOG EXT" },
+ { ATA_CMD_WRITE_LOG_EXT, "WRITE LOG EXT" },
+ { ATA_CMD_READ_LOG_DMA_EXT, "READ LOG DMA EXT" },
+ { ATA_CMD_WRITE_LOG_DMA_EXT, "WRITE LOG DMA EXT" },
+ { ATA_CMD_TRUSTED_NONDATA, "TRUSTED NON-DATA" },
+ { ATA_CMD_TRUSTED_RCV, "TRUSTED RECEIVE" },
+ { ATA_CMD_TRUSTED_RCV_DMA, "TRUSTED RECEIVE DMA" },
+ { ATA_CMD_TRUSTED_SND, "TRUSTED SEND" },
+ { ATA_CMD_TRUSTED_SND_DMA, "TRUSTED SEND DMA" },
+ { ATA_CMD_PMP_READ, "READ BUFFER" },
+ { ATA_CMD_PMP_READ_DMA, "READ BUFFER DMA" },
+ { ATA_CMD_PMP_WRITE, "WRITE BUFFER" },
+ { ATA_CMD_PMP_WRITE_DMA, "WRITE BUFFER DMA" },
+ { ATA_CMD_CONF_OVERLAY, "DEVICE CONFIGURATION OVERLAY" },
+ { ATA_CMD_SEC_SET_PASS, "SECURITY SET PASSWORD" },
+ { ATA_CMD_SEC_UNLOCK, "SECURITY UNLOCK" },
+ { ATA_CMD_SEC_ERASE_PREP, "SECURITY ERASE PREPARE" },
+ { ATA_CMD_SEC_ERASE_UNIT, "SECURITY ERASE UNIT" },
+ { ATA_CMD_SEC_FREEZE_LOCK, "SECURITY FREEZE LOCK" },
+ { ATA_CMD_SEC_DISABLE_PASS, "SECURITY DISABLE PASSWORD" },
+ { ATA_CMD_CONFIG_STREAM, "CONFIGURE STREAM" },
+ { ATA_CMD_SMART, "SMART" },
+ { ATA_CMD_MEDIA_LOCK, "DOOR LOCK" },
+ { ATA_CMD_MEDIA_UNLOCK, "DOOR UNLOCK" },
+ { ATA_CMD_DSM, "DATA SET MANAGEMENT" },
+ { ATA_CMD_CHK_MED_CRD_TYP, "CHECK MEDIA CARD TYPE" },
+ { ATA_CMD_CFA_REQ_EXT_ERR, "CFA REQUEST EXTENDED ERROR" },
+ { ATA_CMD_CFA_WRITE_NE, "CFA WRITE SECTORS WITHOUT ERASE" },
+ { ATA_CMD_CFA_TRANS_SECT, "CFA TRANSLATE SECTOR" },
+ { ATA_CMD_CFA_ERASE, "CFA ERASE SECTORS" },
+ { ATA_CMD_CFA_WRITE_MULT_NE, "CFA WRITE MULTIPLE WITHOUT ERASE" },
+ { ATA_CMD_REQ_SENSE_DATA, "REQUEST SENSE DATA EXT" },
+ { ATA_CMD_SANITIZE_DEVICE, "SANITIZE DEVICE" },
+ { ATA_CMD_READ_LONG, "READ LONG (with retries)" },
+ { ATA_CMD_READ_LONG_ONCE, "READ LONG (without retries)" },
+ { ATA_CMD_WRITE_LONG, "WRITE LONG (with retries)" },
+ { ATA_CMD_WRITE_LONG_ONCE, "WRITE LONG (without retries)" },
+ { ATA_CMD_RESTORE, "RECALIBRATE" },
+ { 0, NULL } /* terminate list */
+ };
+
+ unsigned int i;
+ for (i = 0; cmd_descr[i].text; i++)
+ if (cmd_descr[i].command == command)
+ return cmd_descr[i].text;
+#endif
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(ata_get_cmd_descript);
+
+/**
+ * ata_eh_link_report - report error handling to user
+ * @link: ATA link EH is going on
+ *
+ * Report EH to user.
+ *
+ * LOCKING:
+ * None.
+ */
+static void ata_eh_link_report(struct ata_link *link)
+{
+ struct ata_port *ap = link->ap;
+ struct ata_eh_context *ehc = &link->eh_context;
+ const char *frozen, *desc;
+ char tries_buf[6] = "";
+ int tag, nr_failed = 0;
+
+ if (ehc->i.flags & ATA_EHI_QUIET)
+ return;
+
+ 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) ||
+ ata_dev_phys_link(qc->dev) != link ||
+ ((qc->flags & ATA_QCFLAG_QUIET) &&
+ qc->err_mask == AC_ERR_DEV))
+ 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 (ap->eh_tries < ATA_EH_MAX_TRIES)
+ snprintf(tries_buf, sizeof(tries_buf), " t%d",
+ ap->eh_tries);
+
+ if (ehc->i.dev) {
+ ata_dev_err(ehc->i.dev, "exception Emask 0x%x "
+ "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
+ ehc->i.err_mask, link->sactive, ehc->i.serror,
+ ehc->i.action, frozen, tries_buf);
+ if (desc)
+ ata_dev_err(ehc->i.dev, "%s\n", desc);
+ } else {
+ ata_link_err(link, "exception Emask 0x%x "
+ "SAct 0x%x SErr 0x%x action 0x%x%s%s\n",
+ ehc->i.err_mask, link->sactive, ehc->i.serror,
+ ehc->i.action, frozen, tries_buf);
+ if (desc)
+ ata_link_err(link, "%s\n", desc);
+ }
+
+#ifdef CONFIG_ATA_VERBOSE_ERROR
+ if (ehc->i.serror)
+ ata_link_err(link,
+ "SError: { %s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s}\n",
+ ehc->i.serror & SERR_DATA_RECOVERED ? "RecovData " : "",
+ ehc->i.serror & SERR_COMM_RECOVERED ? "RecovComm " : "",
+ ehc->i.serror & SERR_DATA ? "UnrecovData " : "",
+ ehc->i.serror & SERR_PERSISTENT ? "Persist " : "",
+ ehc->i.serror & SERR_PROTOCOL ? "Proto " : "",
+ ehc->i.serror & SERR_INTERNAL ? "HostInt " : "",
+ ehc->i.serror & SERR_PHYRDY_CHG ? "PHYRdyChg " : "",
+ ehc->i.serror & SERR_PHY_INT_ERR ? "PHYInt " : "",
+ ehc->i.serror & SERR_COMM_WAKE ? "CommWake " : "",
+ ehc->i.serror & SERR_10B_8B_ERR ? "10B8B " : "",
+ ehc->i.serror & SERR_DISPARITY ? "Dispar " : "",
+ ehc->i.serror & SERR_CRC ? "BadCRC " : "",
+ ehc->i.serror & SERR_HANDSHAKE ? "Handshk " : "",
+ ehc->i.serror & SERR_LINK_SEQ_ERR ? "LinkSeq " : "",
+ ehc->i.serror & SERR_TRANS_ST_ERROR ? "TrStaTrns " : "",
+ ehc->i.serror & SERR_UNRECOG_FIS ? "UnrecFIS " : "",
+ ehc->i.serror & SERR_DEV_XCHG ? "DevExch " : "");
+#endif
+
+ for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
+ struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
+ struct ata_taskfile *cmd = &qc->tf, *res = &qc->result_tf;
+ char data_buf[20] = "";
+ char cdb_buf[70] = "";
+
+ if (!(qc->flags & ATA_QCFLAG_FAILED) ||
+ ata_dev_phys_link(qc->dev) != link || !qc->err_mask)
+ continue;
+
+ if (qc->dma_dir != DMA_NONE) {
+ static const char *dma_str[] = {
+ [DMA_BIDIRECTIONAL] = "bidi",
+ [DMA_TO_DEVICE] = "out",
+ [DMA_FROM_DEVICE] = "in",
+ };
+ static const char *prot_str[] = {
+ [ATA_PROT_PIO] = "pio",
+ [ATA_PROT_DMA] = "dma",
+ [ATA_PROT_NCQ] = "ncq",
+ [ATAPI_PROT_PIO] = "pio",
+ [ATAPI_PROT_DMA] = "dma",
+ };
+
+ snprintf(data_buf, sizeof(data_buf), " %s %u %s",
+ prot_str[qc->tf.protocol], qc->nbytes,
+ dma_str[qc->dma_dir]);
+ }
+
+ if (ata_is_atapi(qc->tf.protocol)) {
+ const u8 *cdb = qc->cdb;
+ size_t cdb_len = qc->dev->cdb_len;
+
+ if (qc->scsicmd) {
+ cdb = qc->scsicmd->cmnd;
+ cdb_len = qc->scsicmd->cmd_len;
+ }
+ __scsi_format_command(cdb_buf, sizeof(cdb_buf),
+ cdb, cdb_len);
+ } else {
+ const char *descr = ata_get_cmd_descript(cmd->command);
+ if (descr)
+ ata_dev_err(qc->dev, "failed command: %s\n",
+ descr);
+ }
+
+ ata_dev_err(qc->dev,
+ "cmd %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
+ "tag %d%s\n %s"
+ "res %02x/%02x:%02x:%02x:%02x:%02x/%02x:%02x:%02x:%02x:%02x/%02x "
+ "Emask 0x%x (%s)%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, data_buf, cdb_buf,
+ 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),
+ qc->err_mask & AC_ERR_NCQ ? " <F>" : "");
+
+#ifdef CONFIG_ATA_VERBOSE_ERROR
+ if (res->command & (ATA_BUSY | ATA_DRDY | ATA_DF | ATA_DRQ |
+ ATA_SENSE | ATA_ERR)) {
+ if (res->command & ATA_BUSY)
+ ata_dev_err(qc->dev, "status: { Busy }\n");
+ else
+ ata_dev_err(qc->dev, "status: { %s%s%s%s%s}\n",
+ res->command & ATA_DRDY ? "DRDY " : "",
+ res->command & ATA_DF ? "DF " : "",
+ res->command & ATA_DRQ ? "DRQ " : "",
+ res->command & ATA_SENSE ? "SENSE " : "",
+ res->command & ATA_ERR ? "ERR " : "");
+ }
+
+ if (cmd->command != ATA_CMD_PACKET &&
+ (res->feature & (ATA_ICRC | ATA_UNC | ATA_AMNF |
+ ATA_IDNF | ATA_ABORTED)))
+ ata_dev_err(qc->dev, "error: { %s%s%s%s%s}\n",
+ res->feature & ATA_ICRC ? "ICRC " : "",
+ res->feature & ATA_UNC ? "UNC " : "",
+ res->feature & ATA_AMNF ? "AMNF " : "",
+ res->feature & ATA_IDNF ? "IDNF " : "",
+ res->feature & ATA_ABORTED ? "ABRT " : "");
+#endif
+ }
+}
+
+/**
+ * ata_eh_report - report error handling to user
+ * @ap: ATA port to report EH about
+ *
+ * Report EH to user.
+ *
+ * LOCKING:
+ * None.
+ */
+void ata_eh_report(struct ata_port *ap)
+{
+ struct ata_link *link;
+
+ ata_for_each_link(link, ap, HOST_FIRST)
+ ata_eh_link_report(link);
+}
+
+static int ata_do_reset(struct ata_link *link, ata_reset_fn_t reset,
+ unsigned int *classes, unsigned long deadline,
+ bool clear_classes)
+{
+ struct ata_device *dev;
+
+ if (clear_classes)
+ ata_for_each_dev(dev, link, ALL)
+ classes[dev->devno] = ATA_DEV_UNKNOWN;
+
+ return reset(link, classes, deadline);
+}
+
+static int ata_eh_followup_srst_needed(struct ata_link *link, int rc)
+{
+ if ((link->flags & ATA_LFLAG_NO_SRST) || ata_link_offline(link))
+ return 0;
+ if (rc == -EAGAIN)
+ return 1;
+ if (sata_pmp_supported(link->ap) && ata_is_host_link(link))
+ return 1;
+ return 0;
+}
+
+int ata_eh_reset(struct ata_link *link, int classify,
+ ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
+ ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
+{
+ struct ata_port *ap = link->ap;
+ struct ata_link *slave = ap->slave_link;
+ struct ata_eh_context *ehc = &link->eh_context;
+ struct ata_eh_context *sehc = slave ? &slave->eh_context : NULL;
+ unsigned int *classes = ehc->classes;
+ unsigned int lflags = link->flags;
+ int verbose = !(ehc->i.flags & ATA_EHI_QUIET);
+ int max_tries = 0, try = 0;
+ struct ata_link *failed_link;
+ struct ata_device *dev;
+ unsigned long deadline, now;
+ ata_reset_fn_t reset;
+ unsigned long flags;
+ u32 sstatus;
+ int nr_unknown, rc;
+
+ /*
+ * Prepare to reset
+ */
+ while (ata_eh_reset_timeouts[max_tries] != ULONG_MAX)
+ max_tries++;
+ if (link->flags & ATA_LFLAG_RST_ONCE)
+ max_tries = 1;
+ if (link->flags & ATA_LFLAG_NO_HRST)
+ hardreset = NULL;
+ if (link->flags & ATA_LFLAG_NO_SRST)
+ softreset = NULL;
+
+ /* make sure each reset attempt is at least COOL_DOWN apart */
+ if (ehc->i.flags & ATA_EHI_DID_RESET) {
+ now = jiffies;
+ WARN_ON(time_after(ehc->last_reset, now));
+ deadline = ata_deadline(ehc->last_reset,
+ ATA_EH_RESET_COOL_DOWN);
+ if (time_before(now, deadline))
+ schedule_timeout_uninterruptible(deadline - now);
+ }
+
+ spin_lock_irqsave(ap->lock, flags);
+ ap->pflags |= ATA_PFLAG_RESETTING;
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
+
+ ata_for_each_dev(dev, link, ALL) {
+ /* If we issue an SRST then an ATA drive (not ATAPI)
+ * may change configuration and be in PIO0 timing. If
+ * we do a hard reset (or are coming from power on)
+ * this is true for ATA or ATAPI. Until we've set a
+ * suitable controller mode we should not touch the
+ * bus as we may be talking too fast.
+ */
+ dev->pio_mode = XFER_PIO_0;
+ dev->dma_mode = 0xff;
+
+ /* If the controller has a pio mode setup function
+ * then use it to set the chipset to rights. Don't
+ * touch the DMA setup as that will be dealt with when
+ * configuring devices.
+ */
+ if (ap->ops->set_piomode)
+ ap->ops->set_piomode(ap, dev);
+ }
+
+ /* prefer hardreset */
+ reset = NULL;
+ ehc->i.action &= ~ATA_EH_RESET;
+ if (hardreset) {
+ reset = hardreset;
+ ehc->i.action |= ATA_EH_HARDRESET;
+ } else if (softreset) {
+ reset = softreset;
+ ehc->i.action |= ATA_EH_SOFTRESET;
+ }
+
+ if (prereset) {
+ unsigned long deadline = ata_deadline(jiffies,
+ ATA_EH_PRERESET_TIMEOUT);
+
+ if (slave) {
+ sehc->i.action &= ~ATA_EH_RESET;
+ sehc->i.action |= ehc->i.action;
+ }
+
+ rc = prereset(link, deadline);
+
+ /* If present, do prereset on slave link too. Reset
+ * is skipped iff both master and slave links report
+ * -ENOENT or clear ATA_EH_RESET.
+ */
+ if (slave && (rc == 0 || rc == -ENOENT)) {
+ int tmp;
+
+ tmp = prereset(slave, deadline);
+ if (tmp != -ENOENT)
+ rc = tmp;
+
+ ehc->i.action |= sehc->i.action;
+ }
+
+ if (rc) {
+ if (rc == -ENOENT) {
+ ata_link_dbg(link, "port disabled--ignoring\n");
+ ehc->i.action &= ~ATA_EH_RESET;
+
+ ata_for_each_dev(dev, link, ALL)
+ classes[dev->devno] = ATA_DEV_NONE;
+
+ rc = 0;
+ } else
+ ata_link_err(link,
+ "prereset failed (errno=%d)\n",
+ rc);
+ goto out;
+ }
+
+ /* prereset() might have cleared ATA_EH_RESET. If so,
+ * bang classes, thaw and return.
+ */
+ if (reset && !(ehc->i.action & ATA_EH_RESET)) {
+ ata_for_each_dev(dev, link, ALL)
+ classes[dev->devno] = ATA_DEV_NONE;
+ if ((ap->pflags & ATA_PFLAG_FROZEN) &&
+ ata_is_host_link(link))
+ ata_eh_thaw_port(ap);
+ rc = 0;
+ goto out;
+ }
+ }
+
+ retry:
+ /*
+ * Perform reset
+ */
+ if (ata_is_host_link(link))
+ ata_eh_freeze_port(ap);
+
+ deadline = ata_deadline(jiffies, ata_eh_reset_timeouts[try++]);
+
+ if (reset) {
+ if (verbose)
+ ata_link_info(link, "%s resetting link\n",
+ reset == softreset ? "soft" : "hard");
+
+ /* mark that this EH session started with reset */
+ ehc->last_reset = jiffies;
+ if (reset == hardreset)
+ ehc->i.flags |= ATA_EHI_DID_HARDRESET;
+ else
+ ehc->i.flags |= ATA_EHI_DID_SOFTRESET;
+
+ rc = ata_do_reset(link, reset, classes, deadline, true);
+ if (rc && rc != -EAGAIN) {
+ failed_link = link;
+ goto fail;
+ }
+
+ /* hardreset slave link if existent */
+ if (slave && reset == hardreset) {
+ int tmp;
+
+ if (verbose)
+ ata_link_info(slave, "hard resetting link\n");
+
+ ata_eh_about_to_do(slave, NULL, ATA_EH_RESET);
+ tmp = ata_do_reset(slave, reset, classes, deadline,
+ false);
+ switch (tmp) {
+ case -EAGAIN:
+ rc = -EAGAIN;
+ case 0:
+ break;
+ default:
+ failed_link = slave;
+ rc = tmp;
+ goto fail;
+ }
+ }
+
+ /* perform follow-up SRST if necessary */
+ if (reset == hardreset &&
+ ata_eh_followup_srst_needed(link, rc)) {
+ reset = softreset;
+
+ if (!reset) {
+ ata_link_err(link,
+ "follow-up softreset required but no softreset available\n");
+ failed_link = link;
+ rc = -EINVAL;
+ goto fail;
+ }
+
+ ata_eh_about_to_do(link, NULL, ATA_EH_RESET);
+ rc = ata_do_reset(link, reset, classes, deadline, true);
+ if (rc) {
+ failed_link = link;
+ goto fail;
+ }
+ }
+ } else {
+ if (verbose)
+ ata_link_info(link,
+ "no reset method available, skipping reset\n");
+ if (!(lflags & ATA_LFLAG_ASSUME_CLASS))
+ lflags |= ATA_LFLAG_ASSUME_ATA;
+ }
+
+ /*
+ * Post-reset processing
+ */
+ ata_for_each_dev(dev, link, ALL) {
+ /* After the reset, the device state is PIO 0 and the
+ * controller state is undefined. Reset also wakes up
+ * drives from sleeping mode.
+ */
+ dev->pio_mode = XFER_PIO_0;
+ dev->flags &= ~ATA_DFLAG_SLEEPING;
+
+ if (ata_phys_link_offline(ata_dev_phys_link(dev)))
+ continue;
+
+ /* apply class override */
+ if (lflags & ATA_LFLAG_ASSUME_ATA)
+ classes[dev->devno] = ATA_DEV_ATA;
+ else if (lflags & ATA_LFLAG_ASSUME_SEMB)
+ classes[dev->devno] = ATA_DEV_SEMB_UNSUP;
+ }
+
+ /* record current link speed */
+ if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0)
+ link->sata_spd = (sstatus >> 4) & 0xf;
+ if (slave && sata_scr_read(slave, SCR_STATUS, &sstatus) == 0)
+ slave->sata_spd = (sstatus >> 4) & 0xf;
+
+ /* thaw the port */
+ if (ata_is_host_link(link))
+ ata_eh_thaw_port(ap);
+
+ /* postreset() should clear hardware SError. Although SError
+ * is cleared during link resume, clearing SError here is
+ * necessary as some PHYs raise hotplug events after SRST.
+ * This introduces race condition where hotplug occurs between
+ * reset and here. This race is mediated by cross checking
+ * link onlineness and classification result later.
+ */
+ if (postreset) {
+ postreset(link, classes);
+ if (slave)
+ postreset(slave, classes);
+ }
+
+ /*
+ * Some controllers can't be frozen very well and may set spurious
+ * error conditions during reset. Clear accumulated error
+ * information and re-thaw the port if frozen. As reset is the
+ * final recovery action and we cross check link onlineness against
+ * device classification later, no hotplug event is lost by this.
+ */
+ spin_lock_irqsave(link->ap->lock, flags);
+ memset(&link->eh_info, 0, sizeof(link->eh_info));
+ if (slave)
+ memset(&slave->eh_info, 0, sizeof(link->eh_info));
+ ap->pflags &= ~ATA_PFLAG_EH_PENDING;
+ spin_unlock_irqrestore(link->ap->lock, flags);
+
+ if (ap->pflags & ATA_PFLAG_FROZEN)
+ ata_eh_thaw_port(ap);
+
+ /*
+ * Make sure onlineness and classification result correspond.
+ * Hotplug could have happened during reset and some
+ * controllers fail to wait while a drive is spinning up after
+ * being hotplugged causing misdetection. By cross checking
+ * link on/offlineness and classification result, those
+ * conditions can be reliably detected and retried.
+ */
+ nr_unknown = 0;
+ ata_for_each_dev(dev, link, ALL) {
+ if (ata_phys_link_online(ata_dev_phys_link(dev))) {
+ if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
+ ata_dev_dbg(dev, "link online but device misclassified\n");
+ classes[dev->devno] = ATA_DEV_NONE;
+ nr_unknown++;
+ }
+ } else if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
+ if (ata_class_enabled(classes[dev->devno]))
+ ata_dev_dbg(dev,
+ "link offline, clearing class %d to NONE\n",
+ classes[dev->devno]);
+ classes[dev->devno] = ATA_DEV_NONE;
+ } else if (classes[dev->devno] == ATA_DEV_UNKNOWN) {
+ ata_dev_dbg(dev,
+ "link status unknown, clearing UNKNOWN to NONE\n");
+ classes[dev->devno] = ATA_DEV_NONE;
+ }
+ }
+
+ if (classify && nr_unknown) {
+ if (try < max_tries) {
+ ata_link_warn(link,
+ "link online but %d devices misclassified, retrying\n",
+ nr_unknown);
+ failed_link = link;
+ rc = -EAGAIN;
+ goto fail;
+ }
+ ata_link_warn(link,
+ "link online but %d devices misclassified, "
+ "device detection might fail\n", nr_unknown);
+ }
+
+ /* reset successful, schedule revalidation */
+ ata_eh_done(link, NULL, ATA_EH_RESET);
+ if (slave)
+ ata_eh_done(slave, NULL, ATA_EH_RESET);
+ ehc->last_reset = jiffies; /* update to completion time */
+ ehc->i.action |= ATA_EH_REVALIDATE;
+ link->lpm_policy = ATA_LPM_UNKNOWN; /* reset LPM state */
+
+ rc = 0;
+ out:
+ /* clear hotplug flag */
+ ehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
+ if (slave)
+ sehc->i.flags &= ~ATA_EHI_HOTPLUGGED;
+
+ spin_lock_irqsave(ap->lock, flags);
+ ap->pflags &= ~ATA_PFLAG_RESETTING;
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ return rc;
+
+ fail:
+ /* if SCR isn't accessible on a fan-out port, PMP needs to be reset */
+ if (!ata_is_host_link(link) &&
+ sata_scr_read(link, SCR_STATUS, &sstatus))
+ rc = -ERESTART;
+
+ if (try >= max_tries) {
+ /*
+ * Thaw host port even if reset failed, so that the port
+ * can be retried on the next phy event. This risks
+ * repeated EH runs but seems to be a better tradeoff than
+ * shutting down a port after a botched hotplug attempt.
+ */
+ if (ata_is_host_link(link))
+ ata_eh_thaw_port(ap);
+ goto out;
+ }
+
+ now = jiffies;
+ if (time_before(now, deadline)) {
+ unsigned long delta = deadline - now;
+
+ ata_link_warn(failed_link,
+ "reset failed (errno=%d), retrying in %u secs\n",
+ rc, DIV_ROUND_UP(jiffies_to_msecs(delta), 1000));
+
+ ata_eh_release(ap);
+ while (delta)
+ delta = schedule_timeout_uninterruptible(delta);
+ ata_eh_acquire(ap);
+ }
+
+ /*
+ * While disks spinup behind PMP, some controllers fail sending SRST.
+ * They need to be reset - as well as the PMP - before retrying.
+ */
+ if (rc == -ERESTART) {
+ if (ata_is_host_link(link))
+ ata_eh_thaw_port(ap);
+ goto out;
+ }
+
+ if (try == max_tries - 1) {
+ sata_down_spd_limit(link, 0);
+ if (slave)
+ sata_down_spd_limit(slave, 0);
+ } else if (rc == -EPIPE)
+ sata_down_spd_limit(failed_link, 0);
+
+ if (hardreset)
+ reset = hardreset;
+ goto retry;
+}
+
+static inline void ata_eh_pull_park_action(struct ata_port *ap)
+{
+ struct ata_link *link;
+ struct ata_device *dev;
+ unsigned long flags;
+
+ /*
+ * This function can be thought of as an extended version of
+ * ata_eh_about_to_do() specially crafted to accommodate the
+ * requirements of ATA_EH_PARK handling. Since the EH thread
+ * does not leave the do {} while () loop in ata_eh_recover as
+ * long as the timeout for a park request to *one* device on
+ * the port has not expired, and since we still want to pick
+ * up park requests to other devices on the same port or
+ * timeout updates for the same device, we have to pull
+ * ATA_EH_PARK actions from eh_info into eh_context.i
+ * ourselves at the beginning of each pass over the loop.
+ *
+ * Additionally, all write accesses to &ap->park_req_pending
+ * through reinit_completion() (see below) or complete_all()
+ * (see ata_scsi_park_store()) are protected by the host lock.
+ * As a result we have that park_req_pending.done is zero on
+ * exit from this function, i.e. when ATA_EH_PARK actions for
+ * *all* devices on port ap have been pulled into the
+ * respective eh_context structs. If, and only if,
+ * park_req_pending.done is non-zero by the time we reach
+ * wait_for_completion_timeout(), another ATA_EH_PARK action
+ * has been scheduled for at least one of the devices on port
+ * ap and we have to cycle over the do {} while () loop in
+ * ata_eh_recover() again.
+ */
+
+ spin_lock_irqsave(ap->lock, flags);
+ reinit_completion(&ap->park_req_pending);
+ ata_for_each_link(link, ap, EDGE) {
+ ata_for_each_dev(dev, link, ALL) {
+ struct ata_eh_info *ehi = &link->eh_info;
+
+ link->eh_context.i.dev_action[dev->devno] |=
+ ehi->dev_action[dev->devno] & ATA_EH_PARK;
+ ata_eh_clear_action(link, dev, ehi, ATA_EH_PARK);
+ }
+ }
+ spin_unlock_irqrestore(ap->lock, flags);
+}
+
+static void ata_eh_park_issue_cmd(struct ata_device *dev, int park)
+{
+ struct ata_eh_context *ehc = &dev->link->eh_context;
+ struct ata_taskfile tf;
+ unsigned int err_mask;
+
+ ata_tf_init(dev, &tf);
+ if (park) {
+ ehc->unloaded_mask |= 1 << dev->devno;
+ tf.command = ATA_CMD_IDLEIMMEDIATE;
+ tf.feature = 0x44;
+ tf.lbal = 0x4c;
+ tf.lbam = 0x4e;
+ tf.lbah = 0x55;
+ } else {
+ ehc->unloaded_mask &= ~(1 << dev->devno);
+ tf.command = ATA_CMD_CHK_POWER;
+ }
+
+ tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
+ tf.protocol |= ATA_PROT_NODATA;
+ err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
+ if (park && (err_mask || tf.lbal != 0xc4)) {
+ ata_dev_err(dev, "head unload failed!\n");
+ ehc->unloaded_mask &= ~(1 << dev->devno);
+ }
+}
+
+static int ata_eh_revalidate_and_attach(struct ata_link *link,
+ struct ata_device **r_failed_dev)
+{
+ struct ata_port *ap = link->ap;
+ struct ata_eh_context *ehc = &link->eh_context;
+ struct ata_device *dev;
+ unsigned int new_mask = 0;
+ unsigned long flags;
+ int rc = 0;
+
+ DPRINTK("ENTER\n");
+
+ /* For PATA drive side cable detection to work, IDENTIFY must
+ * be done backwards such that PDIAG- is released by the slave
+ * device before the master device is identified.
+ */
+ ata_for_each_dev(dev, link, ALL_REVERSE) {
+ unsigned int action = ata_eh_dev_action(dev);
+ unsigned int readid_flags = 0;
+
+ if (ehc->i.flags & ATA_EHI_DID_RESET)
+ readid_flags |= ATA_READID_POSTRESET;
+
+ if ((action & ATA_EH_REVALIDATE) && ata_dev_enabled(dev)) {
+ WARN_ON(dev->class == ATA_DEV_PMP);
+
+ if (ata_phys_link_offline(ata_dev_phys_link(dev))) {
+ rc = -EIO;
+ goto err;
+ }
+
+ ata_eh_about_to_do(link, dev, ATA_EH_REVALIDATE);
+ rc = ata_dev_revalidate(dev, ehc->classes[dev->devno],
+ readid_flags);
+ if (rc)
+ goto err;
+
+ ata_eh_done(link, dev, ATA_EH_REVALIDATE);
+
+ /* Configuration may have changed, reconfigure
+ * transfer mode.
+ */
+ ehc->i.flags |= ATA_EHI_SETMODE;
+
+ /* schedule the scsi_rescan_device() here */
+ schedule_work(&(ap->scsi_rescan_task));
+ } else if (dev->class == ATA_DEV_UNKNOWN &&
+ ehc->tries[dev->devno] &&
+ ata_class_enabled(ehc->classes[dev->devno])) {
+ /* Temporarily set dev->class, it will be
+ * permanently set once all configurations are
+ * complete. This is necessary because new
+ * device configuration is done in two
+ * separate loops.
+ */
+ dev->class = ehc->classes[dev->devno];
+
+ if (dev->class == ATA_DEV_PMP)
+ rc = sata_pmp_attach(dev);
+ else
+ rc = ata_dev_read_id(dev, &dev->class,
+ readid_flags, dev->id);
+
+ /* read_id might have changed class, store and reset */
+ ehc->classes[dev->devno] = dev->class;
+ dev->class = ATA_DEV_UNKNOWN;
+
+ switch (rc) {
+ case 0:
+ /* clear error info accumulated during probe */
+ ata_ering_clear(&dev->ering);
+ new_mask |= 1 << dev->devno;
+ break;
+ case -ENOENT:
+ /* IDENTIFY was issued to non-existent
+ * device. No need to reset. Just
+ * thaw and ignore the device.
+ */
+ ata_eh_thaw_port(ap);
+ break;
+ default:
+ goto err;
+ }
+ }
+ }
+
+ /* PDIAG- should have been released, ask cable type if post-reset */
+ if ((ehc->i.flags & ATA_EHI_DID_RESET) && ata_is_host_link(link)) {
+ if (ap->ops->cable_detect)
+ ap->cbl = ap->ops->cable_detect(ap);
+ ata_force_cbl(ap);
+ }
+
+ /* Configure new devices forward such that user doesn't see
+ * device detection messages backwards.
+ */
+ ata_for_each_dev(dev, link, ALL) {
+ if (!(new_mask & (1 << dev->devno)))
+ continue;
+
+ dev->class = ehc->classes[dev->devno];
+
+ if (dev->class == ATA_DEV_PMP)
+ continue;
+
+ ehc->i.flags |= ATA_EHI_PRINTINFO;
+ rc = ata_dev_configure(dev);
+ ehc->i.flags &= ~ATA_EHI_PRINTINFO;
+ if (rc) {
+ dev->class = ATA_DEV_UNKNOWN;
+ goto err;
+ }
+
+ 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;
+ }
+
+ return 0;
+
+ err:
+ *r_failed_dev = dev;
+ DPRINTK("EXIT rc=%d\n", rc);
+ return rc;
+}
+
+/**
+ * ata_set_mode - Program timings and issue SET FEATURES - XFER
+ * @link: link on which timings will be programmed
+ * @r_failed_dev: out parameter for failed device
+ *
+ * Set ATA device disk transfer mode (PIO3, UDMA6, etc.). If
+ * ata_set_mode() fails, pointer to the failing device is
+ * returned in @r_failed_dev.
+ *
+ * LOCKING:
+ * PCI/etc. bus probe sem.
+ *
+ * RETURNS:
+ * 0 on success, negative errno otherwise
+ */
+int ata_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
+{
+ struct ata_port *ap = link->ap;
+ struct ata_device *dev;
+ int rc;
+
+ /* if data transfer is verified, clear DUBIOUS_XFER on ering top */
+ ata_for_each_dev(dev, link, ENABLED) {
+ if (!(dev->flags & ATA_DFLAG_DUBIOUS_XFER)) {
+ struct ata_ering_entry *ent;
+
+ ent = ata_ering_top(&dev->ering);
+ if (ent)
+ ent->eflags &= ~ATA_EFLAG_DUBIOUS_XFER;
+ }
+ }
+
+ /* has private set_mode? */
+ if (ap->ops->set_mode)
+ rc = ap->ops->set_mode(link, r_failed_dev);
+ else
+ rc = ata_do_set_mode(link, r_failed_dev);
+
+ /* if transfer mode has changed, set DUBIOUS_XFER on device */
+ ata_for_each_dev(dev, link, ENABLED) {
+ struct ata_eh_context *ehc = &link->eh_context;
+ u8 saved_xfer_mode = ehc->saved_xfer_mode[dev->devno];
+ u8 saved_ncq = !!(ehc->saved_ncq_enabled & (1 << dev->devno));
+
+ if (dev->xfer_mode != saved_xfer_mode ||
+ ata_ncq_enabled(dev) != saved_ncq)
+ dev->flags |= ATA_DFLAG_DUBIOUS_XFER;
+ }
+
+ return rc;
+}
+
+/**
+ * atapi_eh_clear_ua - Clear ATAPI UNIT ATTENTION after reset
+ * @dev: ATAPI device to clear UA for
+ *
+ * Resets and other operations can make an ATAPI device raise
+ * UNIT ATTENTION which causes the next operation to fail. This
+ * function clears UA.
+ *
+ * LOCKING:
+ * EH context (may sleep).
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+static int atapi_eh_clear_ua(struct ata_device *dev)
+{
+ int i;
+
+ for (i = 0; i < ATA_EH_UA_TRIES; i++) {
+ u8 *sense_buffer = dev->link->ap->sector_buf;
+ u8 sense_key = 0;
+ unsigned int err_mask;
+
+ err_mask = atapi_eh_tur(dev, &sense_key);
+ if (err_mask != 0 && err_mask != AC_ERR_DEV) {
+ ata_dev_warn(dev,
+ "TEST_UNIT_READY failed (err_mask=0x%x)\n",
+ err_mask);
+ return -EIO;
+ }
+
+ if (!err_mask || sense_key != UNIT_ATTENTION)
+ return 0;
+
+ err_mask = atapi_eh_request_sense(dev, sense_buffer, sense_key);
+ if (err_mask) {
+ ata_dev_warn(dev, "failed to clear "
+ "UNIT ATTENTION (err_mask=0x%x)\n", err_mask);
+ return -EIO;
+ }
+ }
+
+ ata_dev_warn(dev, "UNIT ATTENTION persists after %d tries\n",
+ ATA_EH_UA_TRIES);
+
+ return 0;
+}
+
+/**
+ * ata_eh_maybe_retry_flush - Retry FLUSH if necessary
+ * @dev: ATA device which may need FLUSH retry
+ *
+ * If @dev failed FLUSH, it needs to be reported upper layer
+ * immediately as it means that @dev failed to remap and already
+ * lost at least a sector and further FLUSH retrials won't make
+ * any difference to the lost sector. However, if FLUSH failed
+ * for other reasons, for example transmission error, FLUSH needs
+ * to be retried.
+ *
+ * This function determines whether FLUSH failure retry is
+ * necessary and performs it if so.
+ *
+ * RETURNS:
+ * 0 if EH can continue, -errno if EH needs to be repeated.
+ */
+static int ata_eh_maybe_retry_flush(struct ata_device *dev)
+{
+ struct ata_link *link = dev->link;
+ struct ata_port *ap = link->ap;
+ struct ata_queued_cmd *qc;
+ struct ata_taskfile tf;
+ unsigned int err_mask;
+ int rc = 0;
+
+ /* did flush fail for this device? */
+ if (!ata_tag_valid(link->active_tag))
+ return 0;
+
+ qc = __ata_qc_from_tag(ap, link->active_tag);
+ if (qc->dev != dev || (qc->tf.command != ATA_CMD_FLUSH_EXT &&
+ qc->tf.command != ATA_CMD_FLUSH))
+ return 0;
+
+ /* if the device failed it, it should be reported to upper layers */
+ if (qc->err_mask & AC_ERR_DEV)
+ return 0;
+
+ /* flush failed for some other reason, give it another shot */
+ ata_tf_init(dev, &tf);
+
+ tf.command = qc->tf.command;
+ tf.flags |= ATA_TFLAG_DEVICE;
+ tf.protocol = ATA_PROT_NODATA;
+
+ ata_dev_warn(dev, "retrying FLUSH 0x%x Emask 0x%x\n",
+ tf.command, qc->err_mask);
+
+ err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
+ if (!err_mask) {
+ /*
+ * FLUSH is complete but there's no way to
+ * successfully complete a failed command from EH.
+ * Making sure retry is allowed at least once and
+ * retrying it should do the trick - whatever was in
+ * the cache is already on the platter and this won't
+ * cause infinite loop.
+ */
+ qc->scsicmd->allowed = max(qc->scsicmd->allowed, 1);
+ } else {
+ ata_dev_warn(dev, "FLUSH failed Emask 0x%x\n",
+ err_mask);
+ rc = -EIO;
+
+ /* if device failed it, report it to upper layers */
+ if (err_mask & AC_ERR_DEV) {
+ qc->err_mask |= AC_ERR_DEV;
+ qc->result_tf = tf;
+ if (!(ap->pflags & ATA_PFLAG_FROZEN))
+ rc = 0;
+ }
+ }
+ return rc;
+}
+
+/**
+ * ata_eh_set_lpm - configure SATA interface power management
+ * @link: link to configure power management
+ * @policy: the link power management policy
+ * @r_failed_dev: out parameter for failed device
+ *
+ * Enable SATA Interface power management. This will enable
+ * Device Interface Power Management (DIPM) for min_power
+ * policy, and then call driver specific callbacks for
+ * enabling Host Initiated Power management.
+ *
+ * LOCKING:
+ * EH context.
+ *
+ * RETURNS:
+ * 0 on success, -errno on failure.
+ */
+static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
+ struct ata_device **r_failed_dev)
+{
+ struct ata_port *ap = ata_is_host_link(link) ? link->ap : NULL;
+ struct ata_eh_context *ehc = &link->eh_context;
+ struct ata_device *dev, *link_dev = NULL, *lpm_dev = NULL;
+ enum ata_lpm_policy old_policy = link->lpm_policy;
+ bool no_dipm = link->ap->flags & ATA_FLAG_NO_DIPM;
+ unsigned int hints = ATA_LPM_EMPTY | ATA_LPM_HIPM;
+ unsigned int err_mask;
+ int rc;
+
+ /* if the link or host doesn't do LPM, noop */
+ if ((link->flags & ATA_LFLAG_NO_LPM) || (ap && !ap->ops->set_lpm))
+ return 0;
+
+ /*
+ * DIPM is enabled only for MIN_POWER as some devices
+ * misbehave when the host NACKs transition to SLUMBER. Order
+ * device and link configurations such that the host always
+ * allows DIPM requests.
+ */
+ ata_for_each_dev(dev, link, ENABLED) {
+ bool hipm = ata_id_has_hipm(dev->id);
+ bool dipm = ata_id_has_dipm(dev->id) && !no_dipm;
+
+ /* find the first enabled and LPM enabled devices */
+ if (!link_dev)
+ link_dev = dev;
+
+ if (!lpm_dev && (hipm || dipm))
+ lpm_dev = dev;
+
+ hints &= ~ATA_LPM_EMPTY;
+ if (!hipm)
+ hints &= ~ATA_LPM_HIPM;
+
+ /* disable DIPM before changing link config */
+ if (policy != ATA_LPM_MIN_POWER && dipm) {
+ err_mask = ata_dev_set_feature(dev,
+ SETFEATURES_SATA_DISABLE, SATA_DIPM);
+ if (err_mask && err_mask != AC_ERR_DEV) {
+ ata_dev_warn(dev,
+ "failed to disable DIPM, Emask 0x%x\n",
+ err_mask);
+ rc = -EIO;
+ goto fail;
+ }
+ }
+ }
+
+ if (ap) {
+ rc = ap->ops->set_lpm(link, policy, hints);
+ if (!rc && ap->slave_link)
+ rc = ap->ops->set_lpm(ap->slave_link, policy, hints);
+ } else
+ rc = sata_pmp_set_lpm(link, policy, hints);
+
+ /*
+ * Attribute link config failure to the first (LPM) enabled
+ * device on the link.
+ */
+ if (rc) {
+ if (rc == -EOPNOTSUPP) {
+ link->flags |= ATA_LFLAG_NO_LPM;
+ return 0;
+ }
+ dev = lpm_dev ? lpm_dev : link_dev;
+ goto fail;
+ }
+
+ /*
+ * Low level driver acked the transition. Issue DIPM command
+ * with the new policy set.
+ */
+ link->lpm_policy = policy;
+ if (ap && ap->slave_link)
+ ap->slave_link->lpm_policy = policy;
+
+ /* host config updated, enable DIPM if transitioning to MIN_POWER */
+ ata_for_each_dev(dev, link, ENABLED) {
+ if (policy == ATA_LPM_MIN_POWER && !no_dipm &&
+ ata_id_has_dipm(dev->id)) {
+ err_mask = ata_dev_set_feature(dev,
+ SETFEATURES_SATA_ENABLE, SATA_DIPM);
+ if (err_mask && err_mask != AC_ERR_DEV) {
+ ata_dev_warn(dev,
+ "failed to enable DIPM, Emask 0x%x\n",
+ err_mask);
+ rc = -EIO;
+ goto fail;
+ }
+ }
+ }
+
+ link->last_lpm_change = jiffies;
+ link->flags |= ATA_LFLAG_CHANGED;
+
+ return 0;
+
+fail:
+ /* restore the old policy */
+ link->lpm_policy = old_policy;
+ if (ap && ap->slave_link)
+ ap->slave_link->lpm_policy = old_policy;
+
+ /* if no device or only one more chance is left, disable LPM */
+ if (!dev || ehc->tries[dev->devno] <= 2) {
+ ata_link_warn(link, "disabling LPM on the link\n");
+ link->flags |= ATA_LFLAG_NO_LPM;
+ }
+ if (r_failed_dev)
+ *r_failed_dev = dev;
+ return rc;
+}
+
+int ata_link_nr_enabled(struct ata_link *link)
+{
+ struct ata_device *dev;
+ int cnt = 0;
+
+ ata_for_each_dev(dev, link, ENABLED)
+ cnt++;
+ return cnt;
+}
+
+static int ata_link_nr_vacant(struct ata_link *link)
+{
+ struct ata_device *dev;
+ int cnt = 0;
+
+ ata_for_each_dev(dev, link, ALL)
+ if (dev->class == ATA_DEV_UNKNOWN)
+ cnt++;
+ return cnt;
+}
+
+static int ata_eh_skip_recovery(struct ata_link *link)
+{
+ struct ata_port *ap = link->ap;
+ struct ata_eh_context *ehc = &link->eh_context;
+ struct ata_device *dev;
+
+ /* skip disabled links */
+ if (link->flags & ATA_LFLAG_DISABLED)
+ return 1;
+
+ /* skip if explicitly requested */
+ if (ehc->i.flags & ATA_EHI_NO_RECOVERY)
+ return 1;
+
+ /* thaw frozen port and recover failed devices */
+ if ((ap->pflags & ATA_PFLAG_FROZEN) || ata_link_nr_enabled(link))
+ return 0;
+
+ /* reset at least once if reset is requested */
+ if ((ehc->i.action & ATA_EH_RESET) &&
+ !(ehc->i.flags & ATA_EHI_DID_RESET))
+ return 0;
+
+ /* skip if class codes for all vacant slots are ATA_DEV_NONE */
+ ata_for_each_dev(dev, link, ALL) {
+ if (dev->class == ATA_DEV_UNKNOWN &&
+ ehc->classes[dev->devno] != ATA_DEV_NONE)
+ return 0;
+ }
+
+ return 1;
+}
+
+static int ata_count_probe_trials_cb(struct ata_ering_entry *ent, void *void_arg)
+{
+ u64 interval = msecs_to_jiffies(ATA_EH_PROBE_TRIAL_INTERVAL);
+ u64 now = get_jiffies_64();
+ int *trials = void_arg;
+
+ if ((ent->eflags & ATA_EFLAG_OLD_ER) ||
+ (ent->timestamp < now - min(now, interval)))
+ return -1;
+
+ (*trials)++;
+ return 0;
+}
+
+static int ata_eh_schedule_probe(struct ata_device *dev)
+{
+ struct ata_eh_context *ehc = &dev->link->eh_context;
+ struct ata_link *link = ata_dev_phys_link(dev);
+ int trials = 0;
+
+ if (!(ehc->i.probe_mask & (1 << dev->devno)) ||
+ (ehc->did_probe_mask & (1 << dev->devno)))
+ return 0;
+
+ ata_eh_detach_dev(dev);
+ ata_dev_init(dev);
+ ehc->did_probe_mask |= (1 << dev->devno);
+ ehc->i.action |= ATA_EH_RESET;
+ ehc->saved_xfer_mode[dev->devno] = 0;
+ ehc->saved_ncq_enabled &= ~(1 << dev->devno);
+
+ /* the link maybe in a deep sleep, wake it up */
+ if (link->lpm_policy > ATA_LPM_MAX_POWER) {
+ if (ata_is_host_link(link))
+ link->ap->ops->set_lpm(link, ATA_LPM_MAX_POWER,
+ ATA_LPM_EMPTY);
+ else
+ sata_pmp_set_lpm(link, ATA_LPM_MAX_POWER,
+ ATA_LPM_EMPTY);
+ }
+
+ /* Record and count probe trials on the ering. The specific
+ * error mask used is irrelevant. Because a successful device
+ * detection clears the ering, this count accumulates only if
+ * there are consecutive failed probes.
+ *
+ * If the count is equal to or higher than ATA_EH_PROBE_TRIALS
+ * in the last ATA_EH_PROBE_TRIAL_INTERVAL, link speed is
+ * forced to 1.5Gbps.
+ *
+ * This is to work around cases where failed link speed
+ * negotiation results in device misdetection leading to
+ * infinite DEVXCHG or PHRDY CHG events.
+ */
+ ata_ering_record(&dev->ering, 0, AC_ERR_OTHER);
+ ata_ering_map(&dev->ering, ata_count_probe_trials_cb, &trials);
+
+ if (trials > ATA_EH_PROBE_TRIALS)
+ sata_down_spd_limit(link, 1);
+
+ return 1;
+}
+
+static int ata_eh_handle_dev_fail(struct ata_device *dev, int err)
+{
+ struct ata_eh_context *ehc = &dev->link->eh_context;
+
+ /* -EAGAIN from EH routine indicates retry without prejudice.
+ * The requester is responsible for ensuring forward progress.
+ */
+ if (err != -EAGAIN)
+ ehc->tries[dev->devno]--;
+
+ switch (err) {
+ case -ENODEV:
+ /* device missing or wrong IDENTIFY data, schedule probing */
+ ehc->i.probe_mask |= (1 << dev->devno);
+ case -EINVAL:
+ /* give it just one more chance */
+ ehc->tries[dev->devno] = min(ehc->tries[dev->devno], 1);
+ case -EIO:
+ if (ehc->tries[dev->devno] == 1) {
+ /* This is the last chance, better to slow
+ * down than lose it.
+ */
+ sata_down_spd_limit(ata_dev_phys_link(dev), 0);
+ if (dev->pio_mode > XFER_PIO_0)
+ ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
+ }
+ }
+
+ 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_phys_link_offline(ata_dev_phys_link(dev)))
+ ata_eh_detach_dev(dev);
+
+ /* schedule probe if necessary */
+ if (ata_eh_schedule_probe(dev)) {
+ ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
+ memset(ehc->cmd_timeout_idx[dev->devno], 0,
+ sizeof(ehc->cmd_timeout_idx[dev->devno]));
+ }
+
+ return 1;
+ } else {
+ ehc->i.action |= ATA_EH_RESET;
+ return 0;
+ }
+}
+
+/**
+ * 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)
+ * @r_failed_link: out parameter for failed link
+ *
+ * This is the alpha and omega, eum and yang, heart and soul of
+ * libata exception handling. On entry, actions required to
+ * recover each link and hotplug requests are recorded in the
+ * link's 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.
+ */
+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_link **r_failed_link)
+{
+ struct ata_link *link;
+ struct ata_device *dev;
+ int rc, nr_fails;
+ unsigned long flags, deadline;
+
+ DPRINTK("ENTER\n");
+
+ /* prep for recovery */
+ ata_for_each_link(link, ap, EDGE) {
+ struct ata_eh_context *ehc = &link->eh_context;
+
+ /* re-enable link? */
+ if (ehc->i.action & ATA_EH_ENABLE_LINK) {
+ ata_eh_about_to_do(link, NULL, ATA_EH_ENABLE_LINK);
+ spin_lock_irqsave(ap->lock, flags);
+ link->flags &= ~ATA_LFLAG_DISABLED;
+ spin_unlock_irqrestore(ap->lock, flags);
+ ata_eh_done(link, NULL, ATA_EH_ENABLE_LINK);
+ }
+
+ ata_for_each_dev(dev, link, ALL) {
+ if (link->flags & ATA_LFLAG_NO_RETRY)
+ ehc->tries[dev->devno] = 1;
+ else
+ ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
+
+ /* collect port action mask recorded in dev actions */
+ ehc->i.action |= ehc->i.dev_action[dev->devno] &
+ ~ATA_EH_PERDEV_MASK;
+ ehc->i.dev_action[dev->devno] &= ATA_EH_PERDEV_MASK;
+
+ /* process hotplug request */
+ if (dev->flags & ATA_DFLAG_DETACH)
+ ata_eh_detach_dev(dev);
+
+ /* schedule probe if necessary */
+ if (!ata_dev_enabled(dev))
+ ata_eh_schedule_probe(dev);
+ }
+ }
+
+ retry:
+ rc = 0;
+
+ /* if UNLOADING, finish immediately */
+ if (ap->pflags & ATA_PFLAG_UNLOADING)
+ goto out;
+
+ /* prep for EH */
+ ata_for_each_link(link, ap, EDGE) {
+ struct ata_eh_context *ehc = &link->eh_context;
+
+ /* skip EH if possible. */
+ if (ata_eh_skip_recovery(link))
+ ehc->i.action = 0;
+
+ ata_for_each_dev(dev, link, ALL)
+ ehc->classes[dev->devno] = ATA_DEV_UNKNOWN;
+ }
+
+ /* reset */
+ ata_for_each_link(link, ap, EDGE) {
+ struct ata_eh_context *ehc = &link->eh_context;
+
+ if (!(ehc->i.action & ATA_EH_RESET))
+ continue;
+
+ rc = ata_eh_reset(link, ata_link_nr_vacant(link),
+ prereset, softreset, hardreset, postreset);
+ if (rc) {
+ ata_link_err(link, "reset failed, giving up\n");
+ goto out;
+ }
+ }
+
+ do {
+ unsigned long now;
+
+ /*
+ * clears ATA_EH_PARK in eh_info and resets
+ * ap->park_req_pending
+ */
+ ata_eh_pull_park_action(ap);
+
+ deadline = jiffies;
+ ata_for_each_link(link, ap, EDGE) {
+ ata_for_each_dev(dev, link, ALL) {
+ struct ata_eh_context *ehc = &link->eh_context;
+ unsigned long tmp;
+
+ if (dev->class != ATA_DEV_ATA &&
+ dev->class != ATA_DEV_ZAC)
+ continue;
+ if (!(ehc->i.dev_action[dev->devno] &
+ ATA_EH_PARK))
+ continue;
+ tmp = dev->unpark_deadline;
+ if (time_before(deadline, tmp))
+ deadline = tmp;
+ else if (time_before_eq(tmp, jiffies))
+ continue;
+ if (ehc->unloaded_mask & (1 << dev->devno))
+ continue;
+
+ ata_eh_park_issue_cmd(dev, 1);
+ }
+ }
+
+ now = jiffies;
+ if (time_before_eq(deadline, now))
+ break;
+
+ ata_eh_release(ap);
+ deadline = wait_for_completion_timeout(&ap->park_req_pending,
+ deadline - now);
+ ata_eh_acquire(ap);
+ } while (deadline);
+ ata_for_each_link(link, ap, EDGE) {
+ ata_for_each_dev(dev, link, ALL) {
+ if (!(link->eh_context.unloaded_mask &
+ (1 << dev->devno)))
+ continue;
+
+ ata_eh_park_issue_cmd(dev, 0);
+ ata_eh_done(link, dev, ATA_EH_PARK);
+ }
+ }
+
+ /* the rest */
+ nr_fails = 0;
+ ata_for_each_link(link, ap, PMP_FIRST) {
+ struct ata_eh_context *ehc = &link->eh_context;
+
+ if (sata_pmp_attached(ap) && ata_is_host_link(link))
+ goto config_lpm;
+
+ /* revalidate existing devices and attach new ones */
+ rc = ata_eh_revalidate_and_attach(link, &dev);
+ if (rc)
+ goto rest_fail;
+
+ /* if PMP got attached, return, pmp EH will take care of it */
+ if (link->device->class == ATA_DEV_PMP) {
+ ehc->i.action = 0;
+ return 0;
+ }
+
+ /* configure transfer mode if necessary */
+ if (ehc->i.flags & ATA_EHI_SETMODE) {
+ rc = ata_set_mode(link, &dev);
+ if (rc)
+ goto rest_fail;
+ ehc->i.flags &= ~ATA_EHI_SETMODE;
+ }
+
+ /* If reset has been issued, clear UA to avoid
+ * disrupting the current users of the device.
+ */
+ if (ehc->i.flags & ATA_EHI_DID_RESET) {
+ ata_for_each_dev(dev, link, ALL) {
+ if (dev->class != ATA_DEV_ATAPI)
+ continue;
+ rc = atapi_eh_clear_ua(dev);
+ if (rc)
+ goto rest_fail;
+ if (zpodd_dev_enabled(dev))
+ zpodd_post_poweron(dev);
+ }
+ }
+
+ /* retry flush if necessary */
+ ata_for_each_dev(dev, link, ALL) {
+ if (dev->class != ATA_DEV_ATA &&
+ dev->class != ATA_DEV_ZAC)
+ continue;
+ rc = ata_eh_maybe_retry_flush(dev);
+ if (rc)
+ goto rest_fail;
+ }
+
+ config_lpm:
+ /* configure link power saving */
+ if (link->lpm_policy != ap->target_lpm_policy) {
+ rc = ata_eh_set_lpm(link, ap->target_lpm_policy, &dev);
+ if (rc)
+ goto rest_fail;
+ }
+
+ /* this link is okay now */
+ ehc->i.flags = 0;
+ continue;
+
+ rest_fail:
+ nr_fails++;
+ if (dev)
+ ata_eh_handle_dev_fail(dev, rc);
+
+ if (ap->pflags & ATA_PFLAG_FROZEN) {
+ /* PMP reset requires working host port.
+ * Can't retry if it's frozen.
+ */
+ if (sata_pmp_attached(ap))
+ goto out;
+ break;
+ }
+ }
+
+ if (nr_fails)
+ goto retry;
+
+ out:
+ if (rc && r_failed_link)
+ *r_failed_link = link;
+
+ 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.
+ */
+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->flags & ATA_QCFLAG_RETRY)
+ ata_eh_qc_retry(qc);
+ else
+ ata_eh_qc_complete(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);
+ }
+ }
+ }
+
+ /* make sure nr_active_links is zero after EH */
+ WARN_ON(ap->nr_active_links);
+ ap->nr_active_links = 0;
+}
+
+/**
+ * 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)
+{
+ struct ata_device *dev;
+ int rc;
+
+ ata_eh_autopsy(ap);
+ ata_eh_report(ap);
+
+ rc = ata_eh_recover(ap, prereset, softreset, hardreset, postreset,
+ NULL);
+ if (rc) {
+ ata_for_each_dev(dev, &ap->link, ALL)
+ ata_dev_disable(dev);
+ }
+
+ ata_eh_finish(ap);
+}
+
+/**
+ * ata_std_error_handler - standard error handler
+ * @ap: host port to handle error for
+ *
+ * Standard error handler
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ */
+void ata_std_error_handler(struct ata_port *ap)
+{
+ struct ata_port_operations *ops = ap->ops;
+ ata_reset_fn_t hardreset = ops->hardreset;
+
+ /* ignore built-in hardreset if SCR access is not available */
+ if (hardreset == sata_std_hardreset && !sata_scr_valid(&ap->link))
+ hardreset = NULL;
+
+ ata_do_eh(ap, ops->prereset, ops->softreset, hardreset, ops->postreset);
+}
+
+#ifdef CONFIG_PM
+/**
+ * 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;
+ struct ata_device *dev;
+
+ /* are we suspending? */
+ spin_lock_irqsave(ap->lock, flags);
+ if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
+ ap->pm_mesg.event & PM_EVENT_RESUME) {
+ spin_unlock_irqrestore(ap->lock, flags);
+ return;
+ }
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ WARN_ON(ap->pflags & ATA_PFLAG_SUSPENDED);
+
+ /*
+ * If we have a ZPODD attached, check its zero
+ * power ready status before the port is frozen.
+ * Only needed for runtime suspend.
+ */
+ if (PMSG_IS_AUTO(ap->pm_mesg)) {
+ ata_for_each_dev(dev, &ap->link, ENABLED) {
+ if (zpodd_dev_enabled(dev))
+ zpodd_on_suspend(dev);
+ }
+ }
+
+ /* tell ACPI we're suspending */
+ rc = ata_acpi_on_suspend(ap);
+ if (rc)
+ goto out;
+
+ /* suspend */
+ ata_eh_freeze_port(ap);
+
+ if (ap->ops->port_suspend)
+ rc = ap->ops->port_suspend(ap, ap->pm_mesg);
+
+ ata_acpi_set_state(ap, ap->pm_mesg);
+ out:
+ /* update the flags */
+ spin_lock_irqsave(ap->lock, flags);
+
+ ap->pflags &= ~ATA_PFLAG_PM_PENDING;
+ if (rc == 0)
+ ap->pflags |= ATA_PFLAG_SUSPENDED;
+ else if (ap->pflags & ATA_PFLAG_FROZEN)
+ ata_port_schedule_eh(ap);
+
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ return;
+}
+
+/**
+ * ata_eh_handle_port_resume - perform port resume operation
+ * @ap: port to resume
+ *
+ * Resume @ap.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep).
+ */
+static void ata_eh_handle_port_resume(struct ata_port *ap)
+{
+ struct ata_link *link;
+ struct ata_device *dev;
+ unsigned long flags;
+ int rc = 0;
+
+ /* are we resuming? */
+ spin_lock_irqsave(ap->lock, flags);
+ if (!(ap->pflags & ATA_PFLAG_PM_PENDING) ||
+ !(ap->pm_mesg.event & PM_EVENT_RESUME)) {
+ spin_unlock_irqrestore(ap->lock, flags);
+ return;
+ }
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ WARN_ON(!(ap->pflags & ATA_PFLAG_SUSPENDED));
+
+ /*
+ * Error timestamps are in jiffies which doesn't run while
+ * suspended and PHY events during resume isn't too uncommon.
+ * When the two are combined, it can lead to unnecessary speed
+ * downs if the machine is suspended and resumed repeatedly.
+ * Clear error history.
+ */
+ ata_for_each_link(link, ap, HOST_FIRST)
+ ata_for_each_dev(dev, link, ALL)
+ ata_ering_clear(&dev->ering);
+
+ ata_acpi_set_state(ap, ap->pm_mesg);
+
+ if (ap->ops->port_resume)
+ rc = ap->ops->port_resume(ap);
+
+ /* tell ACPI that we're resuming */
+ ata_acpi_on_resume(ap);
+
+ /* update the flags */
+ spin_lock_irqsave(ap->lock, flags);
+ ap->pflags &= ~(ATA_PFLAG_PM_PENDING | ATA_PFLAG_SUSPENDED);
+ spin_unlock_irqrestore(ap->lock, flags);
+}
+#endif /* CONFIG_PM */