]> git.karo-electronics.de Git - linux-beck.git/commitdiff
[PATCH] libata-eh: implement new EH
authorTejun Heo <htejun@gmail.com>
Mon, 15 May 2006 11:58:22 +0000 (20:58 +0900)
committerTejun Heo <htejun@gmail.com>
Mon, 15 May 2006 11:58:22 +0000 (20:58 +0900)
Implement new EH.  The exported interface is ata_do_eh() which is to
be called from ->error_handler and performs the following steps to
recover the failed port.

ata_eh_autopsy() : analyze SError/TF, determine the cause of failure
   and required recovery actions and record it in
   ap->eh_context
ata_eh_report()  : report the failure to user
ata_eh_recover() : perform recovery actions described in ap->eh_context
ata_eh_finish()  : finish failed qcs

LLDDs can customize error handling by modifying eh_context before
calling ata_do_eh() or, if necessary, doing so inbetween each major
steps by calling each step explicitly.

Signed-off-by: Tejun Heo <htejun@gmail.com>
drivers/scsi/libata-core.c
drivers/scsi/libata-eh.c
include/linux/libata.h

index 4def48ed6f46c8ff4d7f7472bfc156d20e73f4d9..ddc47097d37eb26f206c35aa3b1d52523a8418da 100644 (file)
@@ -5440,3 +5440,4 @@ EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
 EXPORT_SYMBOL_GPL(ata_eh_thaw_port);
 EXPORT_SYMBOL_GPL(ata_eh_qc_complete);
 EXPORT_SYMBOL_GPL(ata_eh_qc_retry);
+EXPORT_SYMBOL_GPL(ata_do_eh);
index 1968f2d140f358247cc66ac877bab426f179307b..cd133f83e59511c3eda3772251532cc14bfae006 100644 (file)
@@ -626,3 +626,778 @@ void ata_eh_qc_retry(struct ata_queued_cmd *qc)
                scmd->retries--;
        __ata_eh_qc_complete(qc);
 }
+
+/**
+ *     ata_eh_about_to_do - about to perform eh_action
+ *     @ap: target ATA port
+ *     @action: action about to be performed
+ *
+ *     Called just before performing EH actions to clear related bits
+ *     in @ap->eh_info such that eh actions are not unnecessarily
+ *     repeated.
+ *
+ *     LOCKING:
+ *     None.
+ */
+static void ata_eh_about_to_do(struct ata_port *ap, unsigned int action)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&ap->host_set->lock, flags);
+       ap->eh_info.action &= ~action;
+       ap->flags |= ATA_FLAG_RECOVERED;
+       spin_unlock_irqrestore(&ap->host_set->lock, flags);
+}
+
+/**
+ *     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";
+}
+
+/**
+ *     atapi_eh_request_sense - perform ATAPI REQUEST_SENSE
+ *     @dev: device to perform REQUEST_SENSE to
+ *     @sense_buf: result sense data buffer (SCSI_SENSE_BUFFERSIZE bytes long)
+ *
+ *     Perform ATAPI REQUEST_SENSE after the device reported CHECK
+ *     SENSE.  This function is EH helper.
+ *
+ *     LOCKING:
+ *     Kernel thread context (may sleep).
+ *
+ *     RETURNS:
+ *     0 on success, AC_ERR_* mask on failure
+ */
+static unsigned int atapi_eh_request_sense(struct ata_device *dev,
+                                          unsigned char *sense_buf)
+{
+       struct ata_port *ap = dev->ap;
+       struct ata_taskfile tf;
+       u8 cdb[ATAPI_CDB_LEN];
+
+       DPRINTK("ATAPI request sense\n");
+
+       ata_tf_init(dev, &tf);
+
+       /* FIXME: is this needed? */
+       memset(sense_buf, 0, SCSI_SENSE_BUFFERSIZE);
+
+       /* XXX: why tf_read here? */
+       ap->ops->tf_read(ap, &tf);
+
+       /* fill these in, for the case where they are -not- overwritten */
+       sense_buf[0] = 0x70;
+       sense_buf[2] = tf.feature >> 4;
+
+       memset(cdb, 0, ATAPI_CDB_LEN);
+       cdb[0] = REQUEST_SENSE;
+       cdb[4] = SCSI_SENSE_BUFFERSIZE;
+
+       tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+       tf.command = ATA_CMD_PACKET;
+
+       /* is it pointless to prefer PIO for "safety reasons"? */
+       if (ap->flags & ATA_FLAG_PIO_DMA) {
+               tf.protocol = ATA_PROT_ATAPI_DMA;
+               tf.feature |= ATAPI_PKT_DMA;
+       } else {
+               tf.protocol = ATA_PROT_ATAPI;
+               tf.lbam = (8 * 1024) & 0xff;
+               tf.lbah = (8 * 1024) >> 8;
+       }
+
+       return ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
+                                sense_buf, SCSI_SENSE_BUFFERSIZE);
+}
+
+/**
+ *     ata_eh_analyze_serror - analyze SError for a failed port
+ *     @ap: ATA port to analyze SError for
+ *
+ *     Analyze SError if available and further determine cause of
+ *     failure.
+ *
+ *     LOCKING:
+ *     None.
+ */
+static void ata_eh_analyze_serror(struct ata_port *ap)
+{
+       struct ata_eh_context *ehc = &ap->eh_context;
+       u32 serror = ehc->i.serror;
+       unsigned int err_mask = 0, action = 0;
+
+       if (serror & SERR_PERSISTENT) {
+               err_mask |= AC_ERR_ATA_BUS;
+               action |= ATA_EH_HARDRESET;
+       }
+       if (serror &
+           (SERR_DATA_RECOVERED | SERR_COMM_RECOVERED | SERR_DATA)) {
+               err_mask |= AC_ERR_ATA_BUS;
+               action |= ATA_EH_SOFTRESET;
+       }
+       if (serror & SERR_PROTOCOL) {
+               err_mask |= AC_ERR_HSM;
+               action |= ATA_EH_SOFTRESET;
+       }
+       if (serror & SERR_INTERNAL) {
+               err_mask |= AC_ERR_SYSTEM;
+               action |= ATA_EH_SOFTRESET;
+       }
+       if (serror & (SERR_PHYRDY_CHG | SERR_DEV_XCHG)) {
+               err_mask |= AC_ERR_ATA_BUS;
+               action |= ATA_EH_HARDRESET;
+       }
+
+       ehc->i.err_mask |= err_mask;
+       ehc->i.action |= action;
+}
+
+/**
+ *     ata_eh_analyze_tf - analyze taskfile of a failed qc
+ *     @qc: qc to analyze
+ *     @tf: Taskfile registers to analyze
+ *
+ *     Analyze taskfile of @qc and further determine cause of
+ *     failure.  This function also requests ATAPI sense data if
+ *     avaliable.
+ *
+ *     LOCKING:
+ *     Kernel thread context (may sleep).
+ *
+ *     RETURNS:
+ *     Determined recovery action
+ */
+static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc,
+                                     const struct ata_taskfile *tf)
+{
+       unsigned int tmp, action = 0;
+       u8 stat = tf->command, err = tf->feature;
+
+       if ((stat & (ATA_BUSY | ATA_DRQ | ATA_DRDY)) != ATA_DRDY) {
+               qc->err_mask |= AC_ERR_HSM;
+               return ATA_EH_SOFTRESET;
+       }
+
+       if (!(qc->err_mask & AC_ERR_DEV))
+               return 0;
+
+       switch (qc->dev->class) {
+       case ATA_DEV_ATA:
+               if (err & ATA_ICRC)
+                       qc->err_mask |= AC_ERR_ATA_BUS;
+               if (err & ATA_UNC)
+                       qc->err_mask |= AC_ERR_MEDIA;
+               if (err & ATA_IDNF)
+                       qc->err_mask |= AC_ERR_INVALID;
+               break;
+
+       case ATA_DEV_ATAPI:
+               tmp = atapi_eh_request_sense(qc->dev,
+                                            qc->scsicmd->sense_buffer);
+               if (!tmp) {
+                       /* ATA_QCFLAG_SENSE_VALID is used to tell
+                        * atapi_qc_complete() that sense data is
+                        * already valid.
+                        *
+                        * TODO: interpret sense data and set
+                        * appropriate err_mask.
+                        */
+                       qc->flags |= ATA_QCFLAG_SENSE_VALID;
+               } else
+                       qc->err_mask |= tmp;
+       }
+
+       if (qc->err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT | AC_ERR_ATA_BUS))
+               action |= ATA_EH_SOFTRESET;
+
+       return action;
+}
+
+static int ata_eh_categorize_ering_entry(struct ata_ering_entry *ent)
+{
+       if (ent->err_mask & (AC_ERR_ATA_BUS | AC_ERR_TIMEOUT))
+               return 1;
+
+       if (ent->is_io) {
+               if (ent->err_mask & AC_ERR_HSM)
+                       return 1;
+               if ((ent->err_mask &
+                    (AC_ERR_DEV|AC_ERR_MEDIA|AC_ERR_INVALID)) == AC_ERR_DEV)
+                       return 2;
+       }
+
+       return 0;
+}
+
+struct speed_down_needed_arg {
+       u64 since;
+       int nr_errors[3];
+};
+
+static int speed_down_needed_cb(struct ata_ering_entry *ent, void *void_arg)
+{
+       struct speed_down_needed_arg *arg = void_arg;
+
+       if (ent->timestamp < arg->since)
+               return -1;
+
+       arg->nr_errors[ata_eh_categorize_ering_entry(ent)]++;
+       return 0;
+}
+
+/**
+ *     ata_eh_speed_down_needed - Determine wheter speed down is necessary
+ *     @dev: Device of interest
+ *
+ *     This function examines error ring of @dev and determines
+ *     whether speed down is necessary.  Speed down is necessary if
+ *     there have been more than 3 of Cat-1 errors or 10 of Cat-2
+ *     errors during last 15 minutes.
+ *
+ *     Cat-1 errors are ATA_BUS, TIMEOUT for any command and HSM
+ *     violation for known supported commands.
+ *
+ *     Cat-2 errors are unclassified DEV error for known supported
+ *     command.
+ *
+ *     LOCKING:
+ *     Inherited from caller.
+ *
+ *     RETURNS:
+ *     1 if speed down is necessary, 0 otherwise
+ */
+static int ata_eh_speed_down_needed(struct ata_device *dev)
+{
+       const u64 interval = 15LLU * 60 * HZ;
+       static const int err_limits[3] = { -1, 3, 10 };
+       struct speed_down_needed_arg arg;
+       struct ata_ering_entry *ent;
+       int err_cat;
+       u64 j64;
+
+       ent = ata_ering_top(&dev->ering);
+       if (!ent)
+               return 0;
+
+       err_cat = ata_eh_categorize_ering_entry(ent);
+       if (err_cat == 0)
+               return 0;
+
+       memset(&arg, 0, sizeof(arg));
+
+       j64 = get_jiffies_64();
+       if (j64 >= interval)
+               arg.since = j64 - interval;
+       else
+               arg.since = 0;
+
+       ata_ering_map(&dev->ering, speed_down_needed_cb, &arg);
+
+       return arg.nr_errors[err_cat] > err_limits[err_cat];
+}
+
+/**
+ *     ata_eh_speed_down - record error and speed down if necessary
+ *     @dev: Failed device
+ *     @is_io: Did the device fail during normal IO?
+ *     @err_mask: err_mask of the error
+ *
+ *     Record error and examine error history to determine whether
+ *     adjusting transmission speed is necessary.  It also sets
+ *     transmission limits appropriately if such adjustment is
+ *     necessary.
+ *
+ *     LOCKING:
+ *     Kernel thread context (may sleep).
+ *
+ *     RETURNS:
+ *     0 on success, -errno otherwise
+ */
+static int ata_eh_speed_down(struct ata_device *dev, int is_io,
+                            unsigned int err_mask)
+{
+       if (!err_mask)
+               return 0;
+
+       /* record error and determine whether speed down is necessary */
+       ata_ering_record(&dev->ering, is_io, err_mask);
+
+       if (!ata_eh_speed_down_needed(dev))
+               return 0;
+
+       /* speed down SATA link speed if possible */
+       if (sata_down_spd_limit(dev->ap) == 0)
+               return ATA_EH_HARDRESET;
+
+       /* lower transfer mode */
+       if (ata_down_xfermask_limit(dev, 0) == 0)
+               return ATA_EH_SOFTRESET;
+
+       ata_dev_printk(dev, KERN_ERR,
+                      "speed down requested but no transfer mode left\n");
+       return 0;
+}
+
+/**
+ *     ata_eh_autopsy - analyze error and determine recovery action
+ *     @ap: ATA port to perform autopsy on
+ *
+ *     Analyze why @ap failed and determine which recovery action is
+ *     needed.  This function also sets more detailed AC_ERR_* values
+ *     and fills sense data for ATAPI CHECK SENSE.
+ *
+ *     LOCKING:
+ *     Kernel thread context (may sleep).
+ */
+static void ata_eh_autopsy(struct ata_port *ap)
+{
+       struct ata_eh_context *ehc = &ap->eh_context;
+       unsigned int action = ehc->i.action;
+       struct ata_device *failed_dev = NULL;
+       unsigned int all_err_mask = 0;
+       int tag, is_io = 0;
+       u32 serror;
+       int rc;
+
+       DPRINTK("ENTER\n");
+
+       /* obtain and analyze SError */
+       rc = sata_scr_read(ap, SCR_ERROR, &serror);
+       if (rc == 0) {
+               ehc->i.serror |= serror;
+               ata_eh_analyze_serror(ap);
+       } else if (rc != -EOPNOTSUPP)
+               action |= ATA_EH_HARDRESET;
+
+       /* any real error trumps AC_ERR_OTHER */
+       if (ehc->i.err_mask & ~AC_ERR_OTHER)
+               ehc->i.err_mask &= ~AC_ERR_OTHER;
+
+       all_err_mask |= ehc->i.err_mask;
+
+       for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
+               struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
+
+               if (!(qc->flags & ATA_QCFLAG_FAILED))
+                       continue;
+
+               /* inherit upper level err_mask */
+               qc->err_mask |= ehc->i.err_mask;
+
+               if (qc->err_mask & AC_ERR_TIMEOUT)
+                       action |= ATA_EH_SOFTRESET;
+
+               /* analyze TF */
+               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);
+                       action &= ~ATA_EH_REVALIDATE;
+               }
+
+               /* accumulate error info */
+               failed_dev = qc->dev;
+               all_err_mask |= qc->err_mask;
+               if (qc->flags & ATA_QCFLAG_IO)
+                       is_io = 1;
+       }
+
+       /* speed down iff command was in progress */
+       if (failed_dev)
+               action |= ata_eh_speed_down(failed_dev, is_io, all_err_mask);
+
+       if (all_err_mask)
+               action |= ATA_EH_REVALIDATE;
+
+       ehc->i.dev = failed_dev;
+       ehc->i.action = action;
+
+       DPRINTK("EXIT\n");
+}
+
+/**
+ *     ata_eh_report - report error handling to user
+ *     @ap: ATA port EH is going on
+ *
+ *     Report EH to user.
+ *
+ *     LOCKING:
+ *     None.
+ */
+static void ata_eh_report(struct ata_port *ap)
+{
+       struct ata_eh_context *ehc = &ap->eh_context;
+       const char *frozen, *desc;
+       int tag, nr_failed = 0;
+
+       desc = NULL;
+       if (ehc->i.desc[0] != '\0')
+               desc = ehc->i.desc;
+
+       for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
+               struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
+
+               if (!(qc->flags & ATA_QCFLAG_FAILED))
+                       continue;
+               if (qc->flags & ATA_QCFLAG_SENSE_VALID && !qc->err_mask)
+                       continue;
+
+               nr_failed++;
+       }
+
+       if (!nr_failed && !ehc->i.err_mask)
+               return;
+
+       frozen = "";
+       if (ap->flags & ATA_FLAG_FROZEN)
+               frozen = " frozen";
+
+       if (ehc->i.dev) {
+               ata_dev_printk(ehc->i.dev, KERN_ERR,
+                              "exception Emask 0x%x SErr 0x%x action 0x%x%s\n",
+                              ehc->i.err_mask, ehc->i.serror, ehc->i.action,
+                              frozen);
+               if (desc)
+                       ata_dev_printk(ehc->i.dev, KERN_ERR, "(%s)\n", desc);
+       } else {
+               ata_port_printk(ap, KERN_ERR,
+                               "exception Emask 0x%x SErr 0x%x action 0x%x%s\n",
+                               ehc->i.err_mask, ehc->i.serror, ehc->i.action,
+                               frozen);
+               if (desc)
+                       ata_port_printk(ap, KERN_ERR, "(%s)\n", desc);
+       }
+
+       for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
+               struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
+
+               if (!(qc->flags & ATA_QCFLAG_FAILED) || !qc->err_mask)
+                       continue;
+
+               ata_dev_printk(qc->dev, KERN_ERR, "tag %d cmd 0x%x "
+                              "Emask 0x%x stat 0x%x err 0x%x (%s)\n",
+                              qc->tag, qc->tf.command, qc->err_mask,
+                              qc->result_tf.command, qc->result_tf.feature,
+                              ata_err_string(qc->err_mask));
+       }
+}
+
+static int ata_eh_reset(struct ata_port *ap, ata_reset_fn_t softreset,
+                       ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
+{
+       struct ata_eh_context *ehc = &ap->eh_context;
+       unsigned int classes[ATA_MAX_DEVICES];
+       int tries = ATA_EH_RESET_TRIES;
+       ata_reset_fn_t reset;
+       int rc;
+
+       if (softreset && (!hardreset || (!sata_set_spd_needed(ap) &&
+                                        !(ehc->i.action & ATA_EH_HARDRESET))))
+               reset = softreset;
+       else
+               reset = hardreset;
+
+ retry:
+       ata_port_printk(ap, KERN_INFO, "%s resetting port\n",
+                       reset == softreset ? "soft" : "hard");
+
+       /* reset */
+       ata_eh_about_to_do(ap, ATA_EH_RESET_MASK);
+       ehc->i.flags |= ATA_EHI_DID_RESET;
+
+       rc = ata_do_reset(ap, reset, classes);
+
+       if (rc && --tries) {
+               ata_port_printk(ap, KERN_WARNING,
+                               "%sreset failed, retrying in 5 secs\n",
+                               reset == softreset ? "soft" : "hard");
+               ssleep(5);
+
+               if (reset == hardreset)
+                       sata_down_spd_limit(ap);
+               if (hardreset)
+                       reset = hardreset;
+               goto retry;
+       }
+
+       if (rc == 0) {
+               if (postreset)
+                       postreset(ap, classes);
+
+               /* reset successful, schedule revalidation */
+               ehc->i.dev = NULL;
+               ehc->i.action &= ~ATA_EH_RESET_MASK;
+               ehc->i.action |= ATA_EH_REVALIDATE;
+       }
+
+       return rc;
+}
+
+static int ata_eh_revalidate(struct ata_port *ap,
+                            struct ata_device **r_failed_dev)
+{
+       struct ata_eh_context *ehc = &ap->eh_context;
+       struct ata_device *dev;
+       int i, rc = 0;
+
+       DPRINTK("ENTER\n");
+
+       for (i = 0; i < ATA_MAX_DEVICES; i++) {
+               dev = &ap->device[i];
+
+               if (ehc->i.action & ATA_EH_REVALIDATE && ata_dev_enabled(dev) &&
+                   (!ehc->i.dev || ehc->i.dev == dev)) {
+                       if (ata_port_offline(ap)) {
+                               rc = -EIO;
+                               break;
+                       }
+
+                       ata_eh_about_to_do(ap, ATA_EH_REVALIDATE);
+                       rc = ata_dev_revalidate(dev,
+                                       ehc->i.flags & ATA_EHI_DID_RESET);
+                       if (rc)
+                               break;
+
+                       ehc->i.action &= ~ATA_EH_REVALIDATE;
+               }
+       }
+
+       if (rc)
+               *r_failed_dev = dev;
+
+       DPRINTK("EXIT\n");
+       return rc;
+}
+
+static int ata_port_nr_enabled(struct ata_port *ap)
+{
+       int i, cnt = 0;
+
+       for (i = 0; i < ATA_MAX_DEVICES; i++)
+               if (ata_dev_enabled(&ap->device[i]))
+                       cnt++;
+       return cnt;
+}
+
+/**
+ *     ata_eh_recover - recover host port after error
+ *     @ap: host port to recover
+ *     @softreset: softreset method (can be NULL)
+ *     @hardreset: hardreset method (can be NULL)
+ *     @postreset: postreset method (can be NULL)
+ *
+ *     This is the alpha and omega, eum and yang, heart and soul of
+ *     libata exception handling.  On entry, actions required to
+ *     recover each devices are recorded in eh_context.  This
+ *     function executes all the operations with appropriate retrials
+ *     and fallbacks to resurrect failed devices.
+ *
+ *     LOCKING:
+ *     Kernel thread context (may sleep).
+ *
+ *     RETURNS:
+ *     0 on success, -errno on failure.
+ */
+static int ata_eh_recover(struct ata_port *ap, ata_reset_fn_t softreset,
+                         ata_reset_fn_t hardreset,
+                         ata_postreset_fn_t postreset)
+{
+       struct ata_eh_context *ehc = &ap->eh_context;
+       struct ata_device *dev;
+       int down_xfermask, i, rc;
+
+       DPRINTK("ENTER\n");
+
+       /* prep for recovery */
+       for (i = 0; i < ATA_MAX_DEVICES; i++) {
+               dev = &ap->device[i];
+
+               ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
+       }
+
+ retry:
+       down_xfermask = 0;
+       rc = 0;
+
+       /* skip EH if possible. */
+       if (!ata_port_nr_enabled(ap) && !(ap->flags & ATA_FLAG_FROZEN))
+               ehc->i.action = 0;
+
+       /* reset */
+       if (ehc->i.action & ATA_EH_RESET_MASK) {
+               ata_eh_freeze_port(ap);
+
+               rc = ata_eh_reset(ap, softreset, hardreset, postreset);
+               if (rc) {
+                       ata_port_printk(ap, KERN_ERR,
+                                       "reset failed, giving up\n");
+                       goto out;
+               }
+
+               ata_eh_thaw_port(ap);
+       }
+
+       /* revalidate existing devices */
+       rc = ata_eh_revalidate(ap, &dev);
+       if (rc)
+               goto dev_fail;
+
+       /* configure transfer mode if the port has been reset */
+       if (ehc->i.flags & ATA_EHI_DID_RESET) {
+               rc = ata_set_mode(ap, &dev);
+               if (rc) {
+                       down_xfermask = 1;
+                       goto dev_fail;
+               }
+       }
+
+       goto out;
+
+ dev_fail:
+       switch (rc) {
+       case -ENODEV:
+       case -EINVAL:
+               ehc->tries[dev->devno] = 0;
+               break;
+       case -EIO:
+               sata_down_spd_limit(ap);
+       default:
+               ehc->tries[dev->devno]--;
+               if (down_xfermask &&
+                   ata_down_xfermask_limit(dev, ehc->tries[dev->devno] == 1))
+                       ehc->tries[dev->devno] = 0;
+       }
+
+       /* disable device if it has used up all its chances */
+       if (ata_dev_enabled(dev) && !ehc->tries[dev->devno])
+               ata_dev_disable(dev);
+
+       /* soft didn't work?  be haaaaard */
+       if (ehc->i.flags & ATA_EHI_DID_RESET)
+               ehc->i.action |= ATA_EH_HARDRESET;
+       else
+               ehc->i.action |= ATA_EH_SOFTRESET;
+
+       if (ata_port_nr_enabled(ap)) {
+               ata_port_printk(ap, KERN_WARNING, "failed to recover some "
+                               "devices, retrying in 5 secs\n");
+               ssleep(5);
+       } else {
+               /* no device left, repeat fast */
+               msleep(500);
+       }
+
+       goto retry;
+
+ out:
+       if (rc) {
+               for (i = 0; i < ATA_MAX_DEVICES; i++)
+                       ata_dev_disable(&ap->device[i]);
+       }
+
+       DPRINTK("EXIT, rc=%d\n", rc);
+       return rc;
+}
+
+/**
+ *     ata_eh_finish - finish up EH
+ *     @ap: host port to finish EH for
+ *
+ *     Recovery is complete.  Clean up EH states and retry or finish
+ *     failed qcs.
+ *
+ *     LOCKING:
+ *     None.
+ */
+static void ata_eh_finish(struct ata_port *ap)
+{
+       int tag;
+
+       /* retry or finish qcs */
+       for (tag = 0; tag < ATA_MAX_QUEUE; tag++) {
+               struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);
+
+               if (!(qc->flags & ATA_QCFLAG_FAILED))
+                       continue;
+
+               if (qc->err_mask) {
+                       /* FIXME: Once EH migration is complete,
+                        * generate sense data in this function,
+                        * considering both err_mask and tf.
+                        */
+                       if (qc->err_mask & AC_ERR_INVALID)
+                               ata_eh_qc_complete(qc);
+                       else
+                               ata_eh_qc_retry(qc);
+               } else {
+                       if (qc->flags & ATA_QCFLAG_SENSE_VALID) {
+                               ata_eh_qc_complete(qc);
+                       } else {
+                               /* feed zero TF to sense generation */
+                               memset(&qc->result_tf, 0, sizeof(qc->result_tf));
+                               ata_eh_qc_retry(qc);
+                       }
+               }
+       }
+}
+
+/**
+ *     ata_do_eh - do standard error handling
+ *     @ap: host port to handle error for
+ *     @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_reset_fn_t softreset,
+              ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
+{
+       ata_eh_autopsy(ap);
+       ata_eh_report(ap);
+       ata_eh_recover(ap, softreset, hardreset, postreset);
+       ata_eh_finish(ap);
+}
index 298f9918e37528fab69b8cdce8eb65e0974c8835..9fe46073cf8c1155b08c6ef0baec0714d9c8898a 100644 (file)
@@ -247,6 +247,8 @@ enum {
 
        /* how hard are we gonna try to probe/recover devices */
        ATA_PROBE_MAX_TRIES     = 3,
+       ATA_EH_RESET_TRIES      = 3,
+       ATA_EH_DEV_TRIES        = 3,
 };
 
 enum hsm_task_states {
@@ -727,6 +729,9 @@ extern void ata_eh_thaw_port(struct ata_port *ap);
 extern void ata_eh_qc_complete(struct ata_queued_cmd *qc);
 extern void ata_eh_qc_retry(struct ata_queued_cmd *qc);
 
+extern void ata_do_eh(struct ata_port *ap, ata_reset_fn_t softreset,
+                     ata_reset_fn_t hardreset, ata_postreset_fn_t postreset);
+
 /*
  * printk helpers
  */