[PATCH] libata-hp: implement bootplug

Implement bootplug - boot probing via hotplug path.  While loading,
ata_host_add() simply schedules probing and invokes EH.  After EH
completes, ata_host_add() scans and assicates them with SCSI devices.
EH path is slightly modified to handle this (e.g. no autopsy during
bootplug).  The SCSI part is left in ata_host_add() because it's
shared with legacy path and to keep probing order as before (ATA scan
all ports in host_set then attach all).

Signed-off-by: Tejun Heo <htejun@gmail.com>

2 files changed, 52 insertions, 24 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index c61cfc742388..a42877e6b865 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -5419,7 +5419,7 @@ static struct ata_port * ata_host_add(const struct ata_probe_ent *ent,
 
         DPRINTK("ENTER\n");
 
-        if (!ent->port_ops->probe_reset &&
+        if (!ent->port_ops->probe_reset && !ent->port_ops->error_handler &&
             !(ent->host_flags & (ATA_FLAG_SATA_RESET | ATA_FLAG_SRST))) {
                 printk(KERN_ERR "ata%u: no reset mechanism available\n",
                        port_no);
@@ -5465,7 +5465,6 @@ err_out:
  *      RETURNS:
  *      Number of ports registered.  Zero on error (no ports registered).
  */
-
 int ata_device_add(const struct ata_probe_ent *ent)
 {
         unsigned int count = 0, i;
@@ -5542,19 +5541,6 @@ int ata_device_add(const struct ata_probe_ent *ent)
                 }
                 ap->sata_spd_limit = ap->hw_sata_spd_limit;
 
-                DPRINTK("ata%u: bus probe begin\n", ap->id);
-                rc = ata_bus_probe(ap);
-                DPRINTK("ata%u: bus probe end\n", ap->id);
-
-                if (rc) {
-                        /* FIXME: do something useful here?
-                         * Current libata behavior will
-                         * tear down everything when
-                         * the module is removed
-                         * or the h/w is unplugged.
-                         */
-                }
-
                 rc = scsi_add_host(ap->host, dev);
                 if (rc) {
                         ata_port_printk(ap, KERN_ERR, "scsi_add_host failed\n");
@@ -5564,6 +5550,39 @@ int ata_device_add(const struct ata_probe_ent *ent)
                          * at the very least
                          */
                 }
+
+                if (!ap->ops->probe_reset) {
+                        unsigned long flags;
+
+                        ata_port_probe(ap);
+
+                        /* kick EH for boot probing */
+                        spin_lock_irqsave(&ap->host_set->lock, flags);
+
+                        ap->eh_info.probe_mask = (1 << ATA_MAX_DEVICES) - 1;
+                        ap->eh_info.action |= ATA_EH_SOFTRESET;
+
+                        ap->flags |= ATA_FLAG_LOADING;
+                        ata_port_schedule_eh(ap);
+
+                        spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+                        /* wait for EH to finish */
+                        ata_port_wait_eh(ap);
+                } else {
+                        DPRINTK("ata%u: bus probe begin\n", ap->id);
+                        rc = ata_bus_probe(ap);
+                        DPRINTK("ata%u: bus probe end\n", ap->id);
+
+                        if (rc) {
+                                /* FIXME: do something useful here?
+                                 * Current libata behavior will
+                                 * tear down everything when
+                                 * the module is removed
+                                 * or the h/w is unplugged.
+                                 */
+                        }
+                }
         }
 
         /* probes are done, now scan each port's disk(s) */
diff --git a/drivers/scsi/libata-eh.c b/drivers/scsi/libata-eh.c
index 733dfa532977..70c132bef68e 100644
--- a/drivers/scsi/libata-eh.c
+++ b/drivers/scsi/libata-eh.c
@@ -287,11 +287,14 @@ void ata_scsi_error(struct Scsi_Host *host)
         /* clean up */
         spin_lock_irqsave(hs_lock, flags);
 
-        if (ap->flags & ATA_FLAG_SCSI_HOTPLUG)
-                queue_work(ata_aux_wq, &ap->hotplug_task);
-
-        if (ap->flags & ATA_FLAG_RECOVERED)
-                ata_port_printk(ap, KERN_INFO, "EH complete\n");
+        if (ap->flags & ATA_FLAG_LOADING) {
+                ap->flags &= ~ATA_FLAG_LOADING;
+        } else {
+                if (ap->flags & ATA_FLAG_SCSI_HOTPLUG)
+                        queue_work(ata_aux_wq, &ap->hotplug_task);
+                if (ap->flags & ATA_FLAG_RECOVERED)
+                        ata_port_printk(ap, KERN_INFO, "EH complete\n");
+        }
 
         ap->flags &= ~(ATA_FLAG_SCSI_HOTPLUG | ATA_FLAG_RECOVERED);
 
@@ -1367,6 +1370,7 @@ static int ata_eh_reset(struct ata_port *ap, int classify,
         struct ata_eh_context *ehc = &ap->eh_context;
         unsigned int *classes = ehc->classes;
         int tries = ATA_EH_RESET_TRIES;
+        int verbose = !(ap->flags & ATA_FLAG_LOADING);
         unsigned int action;
         ata_reset_fn_t reset;
         int i, did_followup_srst, rc;
@@ -1414,8 +1418,10 @@ static int ata_eh_reset(struct ata_port *ap, int classify,
         }
 
  retry:
-        ata_port_printk(ap, KERN_INFO, "%s resetting port\n",
-                        reset == softreset ? "soft" : "hard");
+        /* shut up during boot probing */
+        if (verbose)
+                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);
@@ -1799,8 +1805,11 @@ void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
                ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
                ata_postreset_fn_t postreset)
 {
-        ata_eh_autopsy(ap);
-        ata_eh_report(ap);
+        if (!(ap->flags & ATA_FLAG_LOADING)) {
+                ata_eh_autopsy(ap);
+                ata_eh_report(ap);
+        }
+
         ata_eh_recover(ap, prereset, softreset, hardreset, postreset);
         ata_eh_finish(ap);
 }